@ Documentation/RCU/Design/Expedited-Grace-Periods/Expedited-Grace-Periods.rst:41 @ sections.
 RCU-preempt Expedited Grace Periods
 ===================================
 
-``CONFIG_PREEMPT=y`` kernels implement RCU-preempt.
+``CONFIG_PREEMPTION=y`` kernels implement RCU-preempt.
 The overall flow of the handling of a given CPU by an RCU-preempt
 expedited grace period is shown in the following diagram:
 
@ Documentation/RCU/Design/Expedited-Grace-Periods/Expedited-Grace-Periods.rst:115 @ things.
 RCU-sched Expedited Grace Periods
 ---------------------------------
 
-``CONFIG_PREEMPT=n`` kernels implement RCU-sched. The overall flow of
+``CONFIG_PREEMPTION=n`` kernels implement RCU-sched. The overall flow of
 the handling of a given CPU by an RCU-sched expedited grace period is
 shown in the following diagram:
 
@ Documentation/RCU/Design/Requirements/Requirements.rst:81 @ RCU treats a nested set as one big RCU read-side critical section.
 Production-quality implementations of ``rcu_read_lock()`` and
 ``rcu_read_unlock()`` are extremely lightweight, and in fact have
 exactly zero overhead in Linux kernels built for production use with
-``CONFIG_PREEMPT=n``.
+``CONFIG_PREEMPTION=n``.
 
 This guarantee allows ordering to be enforced with extremely low
 overhead to readers, for example:
@ Documentation/RCU/Design/Requirements/Requirements.rst:1185 @ and has become decreasingly so as memory sizes have expanded and memory
 costs have plummeted. However, as I learned from Matt Mackall's
 `bloatwatch <http://elinux.org/Linux_Tiny-FAQ>`__ efforts, memory
 footprint is critically important on single-CPU systems with
-non-preemptible (``CONFIG_PREEMPT=n``) kernels, and thus `tiny
+non-preemptible (``CONFIG_PREEMPTION=n``) kernels, and thus `tiny
 RCU <https://lkml.kernel.org/g/20090113221724.GA15307@linux.vnet.ibm.com>`__
 was born. Josh Triplett has since taken over the small-memory banner
 with his `Linux kernel tinification <https://tiny.wiki.kernel.org/>`__
@ Documentation/RCU/Design/Requirements/Requirements.rst:1501 @ limitations.
 
 Implementations of RCU for which ``rcu_read_lock()`` and
 ``rcu_read_unlock()`` generate no code, such as Linux-kernel RCU when
-``CONFIG_PREEMPT=n``, can be nested arbitrarily deeply. After all, there
+``CONFIG_PREEMPTION=n``, can be nested arbitrarily deeply. After all, there
 is no overhead. Except that if all these instances of
 ``rcu_read_lock()`` and ``rcu_read_unlock()`` are visible to the
 compiler, compilation will eventually fail due to exhausting memory,
@ Documentation/RCU/Design/Requirements/Requirements.rst:1774 @ implementation can be a no-op.
 
 However, once the scheduler has spawned its first kthread, this early
 boot trick fails for ``synchronize_rcu()`` (as well as for
-``synchronize_rcu_expedited()``) in ``CONFIG_PREEMPT=y`` kernels. The
+``synchronize_rcu_expedited()``) in ``CONFIG_PREEMPTION=y`` kernels. The
 reason is that an RCU read-side critical section might be preempted,
 which means that a subsequent ``synchronize_rcu()`` really does have to
 wait for something, as opposed to simply returning immediately.
@ Documentation/RCU/Design/Requirements/Requirements.rst:2013 @ the following:
        5 rcu_read_unlock();
        6 do_something_with(v, user_v);
 
-If the compiler did make this transformation in a ``CONFIG_PREEMPT=n`` kernel
+If the compiler did make this transformation in a ``CONFIG_PREEMPTION=n`` kernel
 build, and if ``get_user()`` did page fault, the result would be a quiescent
 state in the middle of an RCU read-side critical section.  This misplaced
 quiescent state could result in line 4 being a use-after-free access,
@ Documentation/RCU/Design/Requirements/Requirements.rst:2292 @ decides to throw at it.
 
 The Linux kernel is used for real-time workloads, especially in
 conjunction with the `-rt
-patchset <https://rt.wiki.kernel.org/index.php/Main_Page>`__. The
+patchset <https://wiki.linuxfoundation.org/realtime/>`__. The
 real-time-latency response requirements are such that the traditional
 approach of disabling preemption across RCU read-side critical sections
-is inappropriate. Kernels built with ``CONFIG_PREEMPT=y`` therefore use
+is inappropriate. Kernels built with ``CONFIG_PREEMPTION=y`` therefore use
 an RCU implementation that allows RCU read-side critical sections to be
 preempted. This requirement made its presence known after users made it
 clear that an earlier `real-time
@ Documentation/RCU/Design/Requirements/Requirements.rst:2417 @ includes ``rcu_read_lock_bh()``, ``rcu_read_unlock_bh()``,
 ``call_rcu_bh()``, ``rcu_barrier_bh()``, and
 ``rcu_read_lock_bh_held()``. However, the update-side APIs are now
 simple wrappers for other RCU flavors, namely RCU-sched in
-CONFIG_PREEMPT=n kernels and RCU-preempt otherwise.
+CONFIG_PREEMPTION=n kernels and RCU-preempt otherwise.
 
 Sched Flavor (Historical)
 ~~~~~~~~~~~~~~~~~~~~~~~~~
@ Documentation/RCU/Design/Requirements/Requirements.rst:2435 @ not have this property, given that any point in the code outside of an
 RCU read-side critical section can be a quiescent state. Therefore,
 *RCU-sched* was created, which follows “classic” RCU in that an
 RCU-sched grace period waits for pre-existing interrupt and NMI
-handlers. In kernels built with ``CONFIG_PREEMPT=n``, the RCU and
+handlers. In kernels built with ``CONFIG_PREEMPTION=n``, the RCU and
 RCU-sched APIs have identical implementations, while kernels built with
-``CONFIG_PREEMPT=y`` provide a separate implementation for each.
+``CONFIG_PREEMPTION=y`` provide a separate implementation for each.
 
-Note well that in ``CONFIG_PREEMPT=y`` kernels,
+Note well that in ``CONFIG_PREEMPTION=y`` kernels,
 ``rcu_read_lock_sched()`` and ``rcu_read_unlock_sched()`` disable and
 re-enable preemption, respectively. This means that if there was a
 preemption attempt during the RCU-sched read-side critical section,
@ Documentation/RCU/Design/Requirements/Requirements.rst:2602 @ userspace execution also delimit tasks-RCU read-side critical sections.
 
 The tasks-RCU API is quite compact, consisting only of
 ``call_rcu_tasks()``, ``synchronize_rcu_tasks()``, and
-``rcu_barrier_tasks()``. In ``CONFIG_PREEMPT=n`` kernels, trampolines
+``rcu_barrier_tasks()``. In ``CONFIG_PREEMPTION=n`` kernels, trampolines
 cannot be preempted, so these APIs map to ``call_rcu()``,
 ``synchronize_rcu()``, and ``rcu_barrier()``, respectively. In
-``CONFIG_PREEMPT=y`` kernels, trampolines can be preempted, and these
+``CONFIG_PREEMPTION=y`` kernels, trampolines can be preempted, and these
 three APIs are therefore implemented by separate functions that check
 for voluntary context switches.
 
@ Documentation/RCU/checklist.rst:217 @ over a rather long period of time, but improvements are always welcome!
 	the rest of the system.
 
 7.	As of v4.20, a given kernel implements only one RCU flavor,
-	which is RCU-sched for PREEMPT=n and RCU-preempt for PREEMPT=y.
+	which is RCU-sched for PREEMPTION=n and RCU-preempt for PREEMPTION=y.
 	If the updater uses call_rcu() or synchronize_rcu(),
 	then the corresponding readers my use rcu_read_lock() and
 	rcu_read_unlock(), rcu_read_lock_bh() and rcu_read_unlock_bh(),
@ Documentation/RCU/rcubarrier.rst:12 @ RCU (read-copy update) is a synchronization mechanism that can be thought
 of as a replacement for read-writer locking (among other things), but with
 very low-overhead readers that are immune to deadlock, priority inversion,
 and unbounded latency. RCU read-side critical sections are delimited
-by rcu_read_lock() and rcu_read_unlock(), which, in non-CONFIG_PREEMPT
+by rcu_read_lock() and rcu_read_unlock(), which, in non-CONFIG_PREEMPTION
 kernels, generate no code whatsoever.
 
 This means that RCU writers are unaware of the presence of concurrent
@ Documentation/RCU/rcubarrier.rst:332 @ Answer: This cannot happen. The reason is that on_each_cpu() has its last
 	to smp_call_function() and further to smp_call_function_on_cpu(),
 	causing this latter to spin until the cross-CPU invocation of
 	rcu_barrier_func() has completed. This by itself would prevent
-	a grace period from completing on non-CONFIG_PREEMPT kernels,
+	a grace period from completing on non-CONFIG_PREEMPTION kernels,
 	since each CPU must undergo a context switch (or other quiescent
 	state) before the grace period can complete. However, this is
-	of no use in CONFIG_PREEMPT kernels.
+	of no use in CONFIG_PREEMPTION kernels.
 
 	Therefore, on_each_cpu() disables preemption across its call
 	to smp_call_function() and also across the local call to
@ Documentation/RCU/stallwarn.rst:28 @ warnings:
 
 -	A CPU looping with bottom halves disabled.
 
--	For !CONFIG_PREEMPT kernels, a CPU looping anywhere in the kernel
+-	For !CONFIG_PREEMPTION kernels, a CPU looping anywhere in the kernel
 	without invoking schedule().  If the looping in the kernel is
 	really expected and desirable behavior, you might need to add
 	some calls to cond_resched().
@ Documentation/RCU/stallwarn.rst:47 @ warnings:
 	result in the ``rcu_.*kthread starved for`` console-log message,
 	which will include additional debugging information.
 
--	A CPU-bound real-time task in a CONFIG_PREEMPT kernel, which might
+-	A CPU-bound real-time task in a CONFIG_PREEMPTION kernel, which might
 	happen to preempt a low-priority task in the middle of an RCU
 	read-side critical section.   This is especially damaging if
 	that low-priority task is not permitted to run on any other CPU,
@ Documentation/RCU/whatisRCU.rst:687 @ Quick Quiz #1:
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 This section presents a "toy" RCU implementation that is based on
 "classic RCU".  It is also short on performance (but only for updates) and
-on features such as hotplug CPU and the ability to run in CONFIG_PREEMPT
+on features such as hotplug CPU and the ability to run in CONFIG_PREEMPTION
 kernels.  The definitions of rcu_dereference() and rcu_assign_pointer()
 are the same as those shown in the preceding section, so they are omitted.
 ::
@ Documentation/RCU/whatisRCU.rst:743 @ Quick Quiz #2:
 Quick Quiz #3:
 		If it is illegal to block in an RCU read-side
 		critical section, what the heck do you do in
-		PREEMPT_RT, where normal spinlocks can block???
+		CONFIG_PREEMPT_RT, where normal spinlocks can block???
 
 :ref:`Answers to Quick Quiz <8_whatisRCU>`
 
@ Documentation/RCU/whatisRCU.rst:1097 @ Quick Quiz #2:
 		overhead is **negative**.
 
 Answer:
-		Imagine a single-CPU system with a non-CONFIG_PREEMPT
+		Imagine a single-CPU system with a non-CONFIG_PREEMPTION
 		kernel where a routing table is used by process-context
 		code, but can be updated by irq-context code (for example,
 		by an "ICMP REDIRECT" packet).	The usual way of handling
@ Documentation/RCU/whatisRCU.rst:1124 @ Answer:
 Quick Quiz #3:
 		If it is illegal to block in an RCU read-side
 		critical section, what the heck do you do in
-		PREEMPT_RT, where normal spinlocks can block???
+		CONFIG_PREEMPT_RT, where normal spinlocks can block???
 
 Answer:
-		Just as PREEMPT_RT permits preemption of spinlock
+		Just as CONFIG_PREEMPT_RT permits preemption of spinlock
 		critical sections, it permits preemption of RCU
 		read-side critical sections.  It also permits
 		spinlocks blocking while in RCU read-side critical
@ Documentation/admin-guide/kernel-parameters.txt:4100 @
 			value, meaning that RCU_SOFTIRQ is used by default.
 			Specify rcutree.use_softirq=0 to use rcuc kthreads.
 
+			But note that CONFIG_PREEMPT_RT=y kernels disable
+			this kernel boot parameter, forcibly setting it
+			to zero.
+
 	rcutree.rcu_fanout_exact= [KNL]
 			Disable autobalancing of the rcu_node combining
 			tree.  This is used by rcutorture, and might
@ Documentation/admin-guide/kernel-parameters.txt:4482 @
 			only normal grace-period primitives.  No effect
 			on CONFIG_TINY_RCU kernels.
 
+			But note that CONFIG_PREEMPT_RT=y kernels enables
+			this kernel boot parameter, forcibly setting
+			it to the value one, that is, converting any
+			post-boot attempt at an expedited RCU grace
+			period to instead use normal non-expedited
+			grace-period processing.
+
 	rcupdate.rcu_task_ipi_delay= [KNL]
 			Set time in jiffies during which RCU tasks will
 			avoid sending IPIs, starting with the beginning
@ Documentation/driver-api/io-mapping.rst:23 @ A mapping object is created during driver initialization using::
 mappable, while 'size' indicates how large a mapping region to
 enable. Both are in bytes.
 
-This _wc variant provides a mapping which may only be used
-with the io_mapping_map_atomic_wc or io_mapping_map_wc.
+This _wc variant provides a mapping which may only be used with
+io_mapping_map_local_wc() or io_mapping_map_wc().
 
-With this mapping object, individual pages can be mapped either atomically
-or not, depending on the necessary scheduling environment. Of course, atomic
-maps are more efficient::
+With this mapping object, individual pages can be mapped either temporarily
+or long term, depending on the requirements. Of course, temporary maps are
+more efficient.
 
-	void *io_mapping_map_atomic_wc(struct io_mapping *mapping,
-				       unsigned long offset)
+	void *io_mapping_map_local_wc(struct io_mapping *mapping,
+				      unsigned long offset)
 
-'offset' is the offset within the defined mapping region.
-Accessing addresses beyond the region specified in the
-creation function yields undefined results. Using an offset
-which is not page aligned yields an undefined result. The
-return value points to a single page in CPU address space.
+'offset' is the offset within the defined mapping region.  Accessing
+addresses beyond the region specified in the creation function yields
+undefined results. Using an offset which is not page aligned yields an
+undefined result. The return value points to a single page in CPU address
+space.
 
-This _wc variant returns a write-combining map to the
-page and may only be used with mappings created by
-io_mapping_create_wc
+This _wc variant returns a write-combining map to the page and may only be
+used with mappings created by io_mapping_create_wc()
 
-Note that the task may not sleep while holding this page
-mapped.
+Temporary mappings are only valid in the context of the caller. The mapping
+is not guaranteed to be globaly visible.
 
-::
+io_mapping_map_local_wc() has a side effect on X86 32bit as it disables
+migration to make the mapping code work. No caller can rely on this side
+effect.
 
-	void io_mapping_unmap_atomic(void *vaddr)
+Nested mappings need to be undone in reverse order because the mapping
+code uses a stack for keeping track of them::
 
-'vaddr' must be the value returned by the last
-io_mapping_map_atomic_wc call. This unmaps the specified
-page and allows the task to sleep once again.
+ addr1 = io_mapping_map_local_wc(map1, offset1);
+ addr2 = io_mapping_map_local_wc(map2, offset2);
+ ...
+ io_mapping_unmap_local(addr2);
+ io_mapping_unmap_local(addr1);
 
-If you need to sleep while holding the lock, you can use the non-atomic
-variant, although they may be significantly slower.
+The mappings are released with::
 
-::
+	void io_mapping_unmap_local(void *vaddr)
+
+'vaddr' must be the value returned by the last io_mapping_map_local_wc()
+call. This unmaps the specified mapping and undoes eventual side effects of
+the mapping function.
+
+If you need to sleep while holding a mapping, you can use the regular
+variant, although this may be significantly slower::
 
 	void *io_mapping_map_wc(struct io_mapping *mapping,
 				unsigned long offset)
 
-This works like io_mapping_map_atomic_wc except it allows
-the task to sleep while holding the page mapped.
+This works like io_mapping_map_local_wc() except it has no side effects and
+the pointer is globaly visible.
 
-
-::
+The mappings are released with::
 
 	void io_mapping_unmap(void *vaddr)
 
-This works like io_mapping_unmap_atomic, except it is used
-for pages mapped with io_mapping_map_wc.
+Use for pages mapped with io_mapping_map_wc().
 
 At driver close time, the io_mapping object must be freed::
 
 	void io_mapping_free(struct io_mapping *mapping)
-
-Current Implementation
-======================
-
-The initial implementation of these functions uses existing mapping
-mechanisms and so provides only an abstraction layer and no new
-functionality.
-
-On 64-bit processors, io_mapping_create_wc calls ioremap_wc for the whole
-range, creating a permanent kernel-visible mapping to the resource. The
-map_atomic and map functions add the requested offset to the base of the
-virtual address returned by ioremap_wc.
-
-On 32-bit processors with HIGHMEM defined, io_mapping_map_atomic_wc uses
-kmap_atomic_pfn to map the specified page in an atomic fashion;
-kmap_atomic_pfn isn't really supposed to be used with device pages, but it
-provides an efficient mapping for this usage.
-
-On 32-bit processors without HIGHMEM defined, io_mapping_map_atomic_wc and
-io_mapping_map_wc both use ioremap_wc, a terribly inefficient function which
-performs an IPI to inform all processors about the new mapping. This results
-in a significant performance penalty.
@ arch/Kconfig:40 @ config OPROFILE
 	tristate "OProfile system profiling"
 	depends on PROFILING
 	depends on HAVE_OPROFILE
+	depends on !PREEMPT_RT
 	select RING_BUFFER
 	select RING_BUFFER_ALLOW_SWAP
 	help
@ arch/Kconfig:647 @ config HAVE_TIF_NOHZ
 config HAVE_VIRT_CPU_ACCOUNTING
 	bool
 
+config HAVE_VIRT_CPU_ACCOUNTING_IDLE
+	bool
+	help
+	  Architecture has its own way to account idle CPU time and therefore
+	  doesn't implement vtime_account_idle().
+
 config ARCH_HAS_SCALED_CPUTIME
 	bool
 
@ arch/Kconfig:667 @ config HAVE_VIRT_CPU_ACCOUNTING_GEN
 	  some 32-bit arches may require multiple accesses, so proper
 	  locking is needed to protect against concurrent accesses.
 
-
 config HAVE_IRQ_TIME_ACCOUNTING
 	bool
 	help
@ arch/alpha/include/asm/kmap_types.h:1 @
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_KMAP_TYPES_H
-#define _ASM_KMAP_TYPES_H
-
-/* Dummy header just to define km_type. */
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-#define  __WITH_KM_FENCE
-#endif
-
-#include <asm-generic/kmap_types.h>
-
-#undef __WITH_KM_FENCE
-
-#endif
@ arch/alpha/include/asm/spinlock_types.h:5 @
 #ifndef _ALPHA_SPINLOCK_TYPES_H
 #define _ALPHA_SPINLOCK_TYPES_H
 
-#ifndef __LINUX_SPINLOCK_TYPES_H
-# error "please don't include this file directly"
-#endif
-
 typedef struct {
 	volatile unsigned int lock;
 } arch_spinlock_t;
@ arch/arc/Kconfig:510 @ config LINUX_RAM_BASE
 config HIGHMEM
 	bool "High Memory Support"
 	select ARCH_DISCONTIGMEM_ENABLE
+	select KMAP_LOCAL
 	help
 	  With ARC 2G:2G address split, only upper 2G is directly addressable by
 	  kernel. Enable this to potentially allow access to rest of 2G and PAE
@ arch/arc/include/asm/highmem.h:12 @
 #ifdef CONFIG_HIGHMEM
 
 #include <uapi/asm/page.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
+
+#define FIXMAP_SIZE		PGDIR_SIZE
+#define PKMAP_SIZE		PGDIR_SIZE
 
 /* start after vmalloc area */
 #define FIXMAP_BASE		(PAGE_OFFSET - FIXMAP_SIZE - PKMAP_SIZE)
-#define FIXMAP_SIZE		PGDIR_SIZE	/* only 1 PGD worth */
-#define KM_TYPE_NR		((FIXMAP_SIZE >> PAGE_SHIFT)/NR_CPUS)
-#define FIXMAP_ADDR(nr)		(FIXMAP_BASE + ((nr) << PAGE_SHIFT))
+
+#define FIX_KMAP_SLOTS		(KM_MAX_IDX * NR_CPUS)
+#define FIX_KMAP_BEGIN		(0UL)
+#define FIX_KMAP_END		((FIX_KMAP_BEGIN + FIX_KMAP_SLOTS) - 1)
+
+#define FIXADDR_TOP		(FIXMAP_BASE + (FIX_KMAP_END << PAGE_SHIFT))
+
+/*
+ * This should be converted to the asm-generic version, but of course this
+ * is needlessly different from all other architectures. Sigh - tglx
+ */
+#define __fix_to_virt(x)	(FIXADDR_TOP - ((x) << PAGE_SHIFT))
+#define __virt_to_fix(x)	(((FIXADDR_TOP - ((x) & PAGE_MASK))) >> PAGE_SHIFT)
 
 /* start after fixmap area */
 #define PKMAP_BASE		(FIXMAP_BASE + FIXMAP_SIZE)
-#define PKMAP_SIZE		PGDIR_SIZE
 #define LAST_PKMAP		(PKMAP_SIZE >> PAGE_SHIFT)
 #define LAST_PKMAP_MASK		(LAST_PKMAP - 1)
 #define PKMAP_ADDR(nr)		(PKMAP_BASE + ((nr) << PAGE_SHIFT))
@ arch/arc/include/asm/highmem.h:44 @
 
 extern void kmap_init(void);
 
+#define arch_kmap_local_post_unmap(vaddr)			\
+	local_flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE)
+
 static inline void flush_cache_kmaps(void)
 {
 	flush_cache_all();
 }
-
 #endif
 
 #endif
@ arch/arc/include/asm/kmap_types.h:1 @
-/* SPDX-License-Identifier: GPL-2.0-only */
-/*
- * Copyright (C) 2015 Synopsys, Inc. (www.synopsys.com)
- */
-
-#ifndef _ASM_KMAP_TYPES_H
-#define _ASM_KMAP_TYPES_H
-
-/*
- * We primarily need to define KM_TYPE_NR here but that in turn
- * is a function of PGDIR_SIZE etc.
- * To avoid circular deps issue, put everything in asm/highmem.h
- */
-#endif
@ arch/arc/mm/highmem.c:39 @
  *   This means each only has 1 PGDIR_SIZE worth of kvaddr mappings, which means
  *   2M of kvaddr space for typical config (8K page and 11:8:13 traversal split)
  *
- * - fixmap anyhow needs a limited number of mappings. So 2M kvaddr == 256 PTE
- *   slots across NR_CPUS would be more than sufficient (generic code defines
- *   KM_TYPE_NR as 20).
+ * - The fixed KMAP slots for kmap_local/atomic() require KM_MAX_IDX slots per
+ *   CPU. So the number of CPUs sharing a single PTE page is limited.
  *
  * - pkmap being preemptible, in theory could do with more than 256 concurrent
  *   mappings. However, generic pkmap code: map_new_virtual(), doesn't traverse
@ arch/arc/mm/highmem.c:49 @
  */
 
 extern pte_t * pkmap_page_table;
-static pte_t * fixmap_page_table;
-
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
-	int idx, cpu_idx;
-	unsigned long vaddr;
-
-	cpu_idx = kmap_atomic_idx_push();
-	idx = cpu_idx + KM_TYPE_NR * smp_processor_id();
-	vaddr = FIXMAP_ADDR(idx);
-
-	set_pte_at(&init_mm, vaddr, fixmap_page_table + idx,
-		   mk_pte(page, prot));
-
-	return (void *)vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kv)
-{
-	unsigned long kvaddr = (unsigned long)kv;
-
-	if (kvaddr >= FIXMAP_BASE && kvaddr < (FIXMAP_BASE + FIXMAP_SIZE)) {
-
-		/*
-		 * Because preemption is disabled, this vaddr can be associated
-		 * with the current allocated index.
-		 * But in case of multiple live kmap_atomic(), it still relies on
-		 * callers to unmap in right order.
-		 */
-		int cpu_idx = kmap_atomic_idx();
-		int idx = cpu_idx + KM_TYPE_NR * smp_processor_id();
-
-		WARN_ON(kvaddr != FIXMAP_ADDR(idx));
-
-		pte_clear(&init_mm, kvaddr, fixmap_page_table + idx);
-		local_flush_tlb_kernel_range(kvaddr, kvaddr + PAGE_SIZE);
-
-		kmap_atomic_idx_pop();
-	}
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
 
 static noinline pte_t * __init alloc_kmap_pgtable(unsigned long kvaddr)
 {
@ arch/arc/mm/highmem.c:68 @ void __init kmap_init(void)
 {
 	/* Due to recursive include hell, we can't do this in processor.h */
 	BUILD_BUG_ON(PAGE_OFFSET < (VMALLOC_END + FIXMAP_SIZE + PKMAP_SIZE));
+	BUILD_BUG_ON(LAST_PKMAP > PTRS_PER_PTE);
+	BUILD_BUG_ON(FIX_KMAP_SLOTS > PTRS_PER_PTE);
 
-	BUILD_BUG_ON(KM_TYPE_NR > PTRS_PER_PTE);
 	pkmap_page_table = alloc_kmap_pgtable(PKMAP_BASE);
-
-	BUILD_BUG_ON(LAST_PKMAP > PTRS_PER_PTE);
-	fixmap_page_table = alloc_kmap_pgtable(FIXMAP_BASE);
+	alloc_kmap_pgtable(FIXMAP_BASE);
 }
@ arch/arm/Kconfig:34 @ config ARM
 	select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
 	select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT if CPU_V7
 	select ARCH_SUPPORTS_ATOMIC_RMW
+	select ARCH_SUPPORTS_RT if HAVE_POSIX_CPU_TIMERS_TASK_WORK
 	select ARCH_USE_BUILTIN_BSWAP
 	select ARCH_USE_CMPXCHG_LOCKREF
 	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
@ arch/arm/Kconfig:70 @ config ARM
 	select HARDIRQS_SW_RESEND
 	select HAVE_ARCH_AUDITSYSCALL if AEABI && !OABI_COMPAT
 	select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
-	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
+	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU && !PREEMPT_RT
 	select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
 	select HAVE_ARCH_MMAP_RND_BITS if MMU
 	select HAVE_ARCH_SECCOMP
@ arch/arm/Kconfig:110 @ config ARM
 	select HAVE_PERF_EVENTS
 	select HAVE_PERF_REGS
 	select HAVE_PERF_USER_STACK_DUMP
+	select HAVE_PREEMPT_LAZY
 	select MMU_GATHER_RCU_TABLE_FREE if SMP && ARM_LPAE
 	select HAVE_REGS_AND_STACK_ACCESS_API
 	select HAVE_RSEQ
@ arch/arm/Kconfig:126 @ config ARM
 	select OLD_SIGSUSPEND3
 	select PCI_SYSCALL if PCI
 	select PERF_USE_VMALLOC
+	select HAVE_POSIX_CPU_TIMERS_TASK_WORK if !KVM
 	select RTC_LIB
 	select SET_FS
 	select SYS_SUPPORTS_APM_EMULATION
@ arch/arm/Kconfig:1506 @ config HAVE_ARCH_PFN_VALID
 config HIGHMEM
 	bool "High Memory Support"
 	depends on MMU
+	select KMAP_LOCAL
 	help
 	  The address space of ARM processors is only 4 Gigabytes large
 	  and it has to accommodate user address space, kernel address
@ arch/arm/include/asm/fixmap.h:10 @
 #define FIXADDR_TOP		(FIXADDR_END - PAGE_SIZE)
 
 #include <linux/pgtable.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
 
 enum fixed_addresses {
 	FIX_EARLYCON_MEM_BASE,
 	__end_of_permanent_fixed_addresses,
 
 	FIX_KMAP_BEGIN = __end_of_permanent_fixed_addresses,
-	FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * NR_CPUS) - 1,
+	FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1,
 
 	/* Support writing RO kernel text via kprobes, jump labels, etc. */
 	FIX_TEXT_POKE0,
@ arch/arm/include/asm/hardirq.h:5 @
 #ifndef __ASM_HARDIRQ_H
 #define __ASM_HARDIRQ_H
 
-#include <linux/cache.h>
-#include <linux/threads.h>
 #include <asm/irq.h>
 
-typedef struct {
-	unsigned int __softirq_pending;
-} ____cacheline_aligned irq_cpustat_t;
-
-#include <linux/irq_cpustat.h>	/* Standard mappings for irq_cpustat_t above */
-
 #define __ARCH_IRQ_EXIT_IRQS_DISABLED	1
+#define ack_bad_irq ack_bad_irq
+
+#include <asm-generic/hardirq.h>
 
 #endif /* __ASM_HARDIRQ_H */
@ arch/arm/include/asm/highmem.h:5 @
 #ifndef _ASM_HIGHMEM_H
 #define _ASM_HIGHMEM_H
 
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
+#include <asm/fixmap.h>
 
 #define PKMAP_BASE		(PAGE_OFFSET - PMD_SIZE)
 #define LAST_PKMAP		PTRS_PER_PTE
@ arch/arm/include/asm/highmem.h:50 @ extern pte_t *pkmap_page_table;
 
 #ifdef ARCH_NEEDS_KMAP_HIGH_GET
 extern void *kmap_high_get(struct page *page);
-#else
+
+static inline void *arch_kmap_local_high_get(struct page *page)
+{
+	if (IS_ENABLED(CONFIG_DEBUG_HIGHMEM) && !cache_is_vivt())
+		return NULL;
+	return kmap_high_get(page);
+}
+#define arch_kmap_local_high_get arch_kmap_local_high_get
+
+#else /* ARCH_NEEDS_KMAP_HIGH_GET */
 static inline void *kmap_high_get(struct page *page)
 {
 	return NULL;
 }
-#endif
+#endif /* !ARCH_NEEDS_KMAP_HIGH_GET */
 
-/*
- * The following functions are already defined by <linux/highmem.h>
- * when CONFIG_HIGHMEM is not set.
- */
-#ifdef CONFIG_HIGHMEM
-extern void *kmap_atomic_pfn(unsigned long pfn);
-#endif
+#define arch_kmap_local_post_map(vaddr, pteval)				\
+	local_flush_tlb_kernel_page(vaddr)
+
+#define arch_kmap_local_pre_unmap(vaddr)				\
+do {									\
+	if (cache_is_vivt())						\
+		__cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE);	\
+} while (0)
+
+#define arch_kmap_local_post_unmap(vaddr)				\
+	local_flush_tlb_kernel_page(vaddr)
 
 #endif
@ arch/arm/include/asm/irq.h:34 @ void handle_IRQ(unsigned int, struct pt_regs *);
 void init_IRQ(void);
 
 #ifdef CONFIG_SMP
+#include <linux/cpumask.h>
+
 extern void arch_trigger_cpumask_backtrace(const cpumask_t *mask,
 					   bool exclude_self);
 #define arch_trigger_cpumask_backtrace arch_trigger_cpumask_backtrace
@ arch/arm/include/asm/kmap_types.h:1 @
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef __ARM_KMAP_TYPES_H
-#define __ARM_KMAP_TYPES_H
-
-/*
- * This is the "bare minimum".  AIO seems to require this.
- */
-#define KM_TYPE_NR 16
-
-#endif
@ arch/arm/include/asm/spinlock_types.h:5 @
 #ifndef __ASM_SPINLOCK_TYPES_H
 #define __ASM_SPINLOCK_TYPES_H
 
-#ifndef __LINUX_SPINLOCK_TYPES_H
-# error "please don't include this file directly"
-#endif
-
 #define TICKET_SHIFT	16
 
 typedef struct {
@ arch/arm/include/asm/thread_info.h:49 @ struct cpu_context_save {
 struct thread_info {
 	unsigned long		flags;		/* low level flags */
 	int			preempt_count;	/* 0 => preemptable, <0 => bug */
+	int			preempt_lazy_count; /* 0 => preemptable, <0 => bug */
 	mm_segment_t		addr_limit;	/* address limit */
 	struct task_struct	*task;		/* main task structure */
 	__u32			cpu;		/* cpu */
@ arch/arm/include/asm/thread_info.h:138 @ extern int vfp_restore_user_hwstate(struct user_vfp *,
 #define TIF_SYSCALL_TRACE	4	/* syscall trace active */
 #define TIF_SYSCALL_AUDIT	5	/* syscall auditing active */
 #define TIF_SYSCALL_TRACEPOINT	6	/* syscall tracepoint instrumentation */
-#define TIF_SECCOMP		7	/* seccomp syscall filtering active */
+#define TIF_NEED_RESCHED_LAZY	7
+#define TIF_SECCOMP		8	/* seccomp syscall filtering active */
 
 #define TIF_USING_IWMMXT	17
 #define TIF_MEMDIE		18	/* is terminating due to OOM killer */
@ arch/arm/include/asm/thread_info.h:148 @ extern int vfp_restore_user_hwstate(struct user_vfp *,
 #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
 #define _TIF_NOTIFY_RESUME	(1 << TIF_NOTIFY_RESUME)
+#define _TIF_NEED_RESCHED_LAZY	(1 << TIF_NEED_RESCHED_LAZY)
 #define _TIF_UPROBE		(1 << TIF_UPROBE)
 #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
 #define _TIF_SYSCALL_AUDIT	(1 << TIF_SYSCALL_AUDIT)
@ arch/arm/include/asm/thread_info.h:164 @ extern int vfp_restore_user_hwstate(struct user_vfp *,
  * Change these and you break ASM code in entry-common.S
  */
 #define _TIF_WORK_MASK		(_TIF_NEED_RESCHED | _TIF_SIGPENDING | \
-				 _TIF_NOTIFY_RESUME | _TIF_UPROBE)
+				 _TIF_NOTIFY_RESUME | _TIF_UPROBE | \
+				 _TIF_NEED_RESCHED_LAZY)
 
 #endif /* __KERNEL__ */
 #endif /* __ASM_ARM_THREAD_INFO_H */
@ arch/arm/kernel/asm-offsets.c:46 @ int main(void)
   BLANK();
   DEFINE(TI_FLAGS,		offsetof(struct thread_info, flags));
   DEFINE(TI_PREEMPT,		offsetof(struct thread_info, preempt_count));
+  DEFINE(TI_PREEMPT_LAZY,	offsetof(struct thread_info, preempt_lazy_count));
   DEFINE(TI_ADDR_LIMIT,		offsetof(struct thread_info, addr_limit));
   DEFINE(TI_TASK,		offsetof(struct thread_info, task));
   DEFINE(TI_CPU,		offsetof(struct thread_info, cpu));
@ arch/arm/kernel/entry-armv.S:209 @ __irq_svc:
 
 #ifdef CONFIG_PREEMPTION
 	ldr	r8, [tsk, #TI_PREEMPT]		@ get preempt count
-	ldr	r0, [tsk, #TI_FLAGS]		@ get flags
 	teq	r8, #0				@ if preempt count != 0
+	bne	1f				@ return from exeption
+	ldr	r0, [tsk, #TI_FLAGS]		@ get flags
+	tst	r0, #_TIF_NEED_RESCHED		@ if NEED_RESCHED is set
+	blne	svc_preempt			@ preempt!
+
+	ldr	r8, [tsk, #TI_PREEMPT_LAZY]	@ get preempt lazy count
+	teq	r8, #0				@ if preempt lazy count != 0
 	movne	r0, #0				@ force flags to 0
-	tst	r0, #_TIF_NEED_RESCHED
+	tst	r0, #_TIF_NEED_RESCHED_LAZY
 	blne	svc_preempt
+1:
 #endif
 
 	svc_exit r5, irq = 1			@ return from exception
@ arch/arm/kernel/entry-armv.S:235 @ svc_preempt:
 1:	bl	preempt_schedule_irq		@ irq en/disable is done inside
 	ldr	r0, [tsk, #TI_FLAGS]		@ get new tasks TI_FLAGS
 	tst	r0, #_TIF_NEED_RESCHED
+	bne	1b
+	tst	r0, #_TIF_NEED_RESCHED_LAZY
 	reteq	r8				@ go again
-	b	1b
+	ldr	r0, [tsk, #TI_PREEMPT_LAZY]	@ get preempt lazy count
+	teq	r0, #0				@ if preempt lazy count != 0
+	beq	1b
+	ret	r8				@ go again
+
 #endif
 
 __und_fault:
@ arch/arm/kernel/entry-common.S:56 @ __ret_fast_syscall:
 	cmp	r2, #TASK_SIZE
 	blne	addr_limit_check_failed
 	ldr	r1, [tsk, #TI_FLAGS]		@ re-check for syscall tracing
-	tst	r1, #_TIF_SYSCALL_WORK | _TIF_WORK_MASK
+	tst	r1, #((_TIF_SYSCALL_WORK | _TIF_WORK_MASK) & ~_TIF_SECCOMP)
+	bne	fast_work_pending
+	tst	r1, #_TIF_SECCOMP
 	bne	fast_work_pending
 
 
@ arch/arm/kernel/entry-common.S:95 @ __ret_fast_syscall:
 	cmp	r2, #TASK_SIZE
 	blne	addr_limit_check_failed
 	ldr	r1, [tsk, #TI_FLAGS]		@ re-check for syscall tracing
-	tst	r1, #_TIF_SYSCALL_WORK | _TIF_WORK_MASK
+	tst	r1, #((_TIF_SYSCALL_WORK | _TIF_WORK_MASK) & ~_TIF_SECCOMP)
+	bne	do_slower_path
+	tst	r1, #_TIF_SECCOMP
 	beq	no_work_pending
+do_slower_path:
  UNWIND(.fnend		)
 ENDPROC(ret_fast_syscall)
 
@ arch/arm/kernel/signal.c:652 @ do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall)
 	 */
 	trace_hardirqs_off();
 	do {
-		if (likely(thread_flags & _TIF_NEED_RESCHED)) {
+		if (likely(thread_flags & (_TIF_NEED_RESCHED |
+					   _TIF_NEED_RESCHED_LAZY))) {
 			schedule();
 		} else {
 			if (unlikely(!user_mode(regs)))
@ arch/arm/kernel/smp.c:674 @ static void do_handle_IPI(int ipinr)
 		break;
 
 	case IPI_CPU_BACKTRACE:
-		printk_nmi_enter();
 		nmi_cpu_backtrace(get_irq_regs());
-		printk_nmi_exit();
 		break;
 
 	default:
@ arch/arm/mm/Makefile:22 @ obj-$(CONFIG_MODULES)		+= proc-syms.o
 obj-$(CONFIG_DEBUG_VIRTUAL)	+= physaddr.o
 
 obj-$(CONFIG_ALIGNMENT_TRAP)	+= alignment.o
-obj-$(CONFIG_HIGHMEM)		+= highmem.o
 obj-$(CONFIG_HUGETLB_PAGE)	+= hugetlbpage.o
 obj-$(CONFIG_ARM_PV_FIXUP)	+= pv-fixup-asm.o
 
@ arch/arm/mm/cache-feroceon-l2.c:52 @ static inline unsigned long l2_get_va(unsigned long paddr)
 	 * we simply install a virtual mapping for it only for the
 	 * TLB lookup to occur, hence no need to flush the untouched
 	 * memory mapping afterwards (note: a cache flush may happen
-	 * in some circumstances depending on the path taken in kunmap_atomic).
+	 * in some circumstances depending on the path taken in kunmap_local).
 	 */
-	void *vaddr = kmap_atomic_pfn(paddr >> PAGE_SHIFT);
+	void *vaddr = kmap_local_pfn(paddr >> PAGE_SHIFT);
 	return (unsigned long)vaddr + (paddr & ~PAGE_MASK);
 #else
 	return __phys_to_virt(paddr);
@ arch/arm/mm/cache-feroceon-l2.c:64 @ static inline unsigned long l2_get_va(unsigned long paddr)
 static inline void l2_put_va(unsigned long vaddr)
 {
 #ifdef CONFIG_HIGHMEM
-	kunmap_atomic((void *)vaddr);
+	kunmap_local((void *)vaddr);
 #endif
 }
 
@ arch/arm/mm/cache-xsc3l2.c:62 @ static inline void l2_unmap_va(unsigned long va)
 {
 #ifdef CONFIG_HIGHMEM
 	if (va != -1)
-		kunmap_atomic((void *)va);
+		kunmap_local((void *)va);
 #endif
 }
 
@ arch/arm/mm/cache-xsc3l2.c:78 @ static inline unsigned long l2_map_va(unsigned long pa, unsigned long prev_va)
 		 * in place for it.
 		 */
 		l2_unmap_va(prev_va);
-		va = (unsigned long)kmap_atomic_pfn(pa >> PAGE_SHIFT);
+		va = (unsigned long)kmap_local_pfn(pa >> PAGE_SHIFT);
 	}
 	return va + (pa_offset >> (32 - PAGE_SHIFT));
 #else
@ arch/arm/mm/fault.c:403 @ do_translation_fault(unsigned long addr, unsigned int fsr,
 	if (addr < TASK_SIZE)
 		return do_page_fault(addr, fsr, regs);
 
+	if (interrupts_enabled(regs))
+		local_irq_enable();
+
 	if (user_mode(regs))
 		goto bad_area;
 
@ arch/arm/mm/fault.c:476 @ do_translation_fault(unsigned long addr, unsigned int fsr,
 static int
 do_sect_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
 {
+	if (interrupts_enabled(regs))
+		local_irq_enable();
+
 	do_bad_area(addr, fsr, regs);
 	return 0;
 }
@ arch/arm/mm/highmem.c:1 @
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * arch/arm/mm/highmem.c -- ARM highmem support
- *
- * Author:	Nicolas Pitre
- * Created:	september 8, 2008
- * Copyright:	Marvell Semiconductors Inc.
- */
-
-#include <linux/module.h>
-#include <linux/highmem.h>
-#include <linux/interrupt.h>
-#include <asm/fixmap.h>
-#include <asm/cacheflush.h>
-#include <asm/tlbflush.h>
-#include "mm.h"
-
-static inline void set_fixmap_pte(int idx, pte_t pte)
-{
-	unsigned long vaddr = __fix_to_virt(idx);
-	pte_t *ptep = virt_to_kpte(vaddr);
-
-	set_pte_ext(ptep, pte, 0);
-	local_flush_tlb_kernel_page(vaddr);
-}
-
-static inline pte_t get_fixmap_pte(unsigned long vaddr)
-{
-	pte_t *ptep = virt_to_kpte(vaddr);
-
-	return *ptep;
-}
-
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
-	unsigned int idx;
-	unsigned long vaddr;
-	void *kmap;
-	int type;
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-	/*
-	 * There is no cache coherency issue when non VIVT, so force the
-	 * dedicated kmap usage for better debugging purposes in that case.
-	 */
-	if (!cache_is_vivt())
-		kmap = NULL;
-	else
-#endif
-		kmap = kmap_high_get(page);
-	if (kmap)
-		return kmap;
-
-	type = kmap_atomic_idx_push();
-
-	idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
-	vaddr = __fix_to_virt(idx);
-#ifdef CONFIG_DEBUG_HIGHMEM
-	/*
-	 * With debugging enabled, kunmap_atomic forces that entry to 0.
-	 * Make sure it was indeed properly unmapped.
-	 */
-	BUG_ON(!pte_none(get_fixmap_pte(vaddr)));
-#endif
-	/*
-	 * When debugging is off, kunmap_atomic leaves the previous mapping
-	 * in place, so the contained TLB flush ensures the TLB is updated
-	 * with the new mapping.
-	 */
-	set_fixmap_pte(idx, mk_pte(page, prot));
-
-	return (void *)vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kvaddr)
-{
-	unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-	int idx, type;
-
-	if (kvaddr >= (void *)FIXADDR_START) {
-		type = kmap_atomic_idx();
-		idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
-
-		if (cache_is_vivt())
-			__cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE);
-#ifdef CONFIG_DEBUG_HIGHMEM
-		BUG_ON(vaddr != __fix_to_virt(idx));
-		set_fixmap_pte(idx, __pte(0));
-#else
-		(void) idx;  /* to kill a warning */
-#endif
-		kmap_atomic_idx_pop();
-	} else if (vaddr >= PKMAP_ADDR(0) && vaddr < PKMAP_ADDR(LAST_PKMAP)) {
-		/* this address was obtained through kmap_high_get() */
-		kunmap_high(pte_page(pkmap_page_table[PKMAP_NR(vaddr)]));
-	}
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
-
-void *kmap_atomic_pfn(unsigned long pfn)
-{
-	unsigned long vaddr;
-	int idx, type;
-	struct page *page = pfn_to_page(pfn);
-
-	preempt_disable();
-	pagefault_disable();
-	if (!PageHighMem(page))
-		return page_address(page);
-
-	type = kmap_atomic_idx_push();
-	idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
-	vaddr = __fix_to_virt(idx);
-#ifdef CONFIG_DEBUG_HIGHMEM
-	BUG_ON(!pte_none(get_fixmap_pte(vaddr)));
-#endif
-	set_fixmap_pte(idx, pfn_pte(pfn, kmap_prot));
-
-	return (void *)vaddr;
-}
@ arch/arm64/Kconfig:79 @ config ARM64
 	select ARCH_SUPPORTS_ATOMIC_RMW
 	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && (GCC_VERSION >= 50000 || CC_IS_CLANG)
 	select ARCH_SUPPORTS_NUMA_BALANCING
+	select ARCH_SUPPORTS_RT if HAVE_POSIX_CPU_TIMERS_TASK_WORK
 	select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
 	select ARCH_WANT_DEFAULT_BPF_JIT
 	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
@ arch/arm64/Kconfig:177 @ config ARM64
 	select HAVE_PERF_EVENTS
 	select HAVE_PERF_REGS
 	select HAVE_PERF_USER_STACK_DUMP
+	select HAVE_PREEMPT_LAZY
 	select HAVE_REGS_AND_STACK_ACCESS_API
 	select HAVE_FUNCTION_ARG_ACCESS_API
 	select HAVE_FUTEX_CMPXCHG if FUTEX
@ arch/arm64/Kconfig:199 @ config ARM64
 	select PCI_DOMAINS_GENERIC if PCI
 	select PCI_ECAM if (ACPI && PCI)
 	select PCI_SYSCALL if PCI
+	select HAVE_POSIX_CPU_TIMERS_TASK_WORK if !KVM
 	select POWER_RESET
 	select POWER_SUPPLY
 	select SET_FS
@ arch/arm64/include/asm/hardirq.h:16 @
 #include <asm/kvm_arm.h>
 #include <asm/sysreg.h>
 
-typedef struct {
-	unsigned int __softirq_pending;
-} ____cacheline_aligned irq_cpustat_t;
-
-#include <linux/irq_cpustat.h>	/* Standard mappings for irq_cpustat_t above */
+#define ack_bad_irq ack_bad_irq
+#include <asm-generic/hardirq.h>
 
 #define __ARCH_IRQ_EXIT_IRQS_DISABLED	1
 
@ arch/arm64/include/asm/preempt.h:73 @ static inline bool __preempt_count_dec_and_test(void)
 	 * interrupt occurring between the non-atomic READ_ONCE/WRITE_ONCE
 	 * pair.
 	 */
-	return !pc || !READ_ONCE(ti->preempt_count);
+	if (!pc || !READ_ONCE(ti->preempt_count))
+		return true;
+#ifdef CONFIG_PREEMPT_LAZY
+	if ((pc & ~PREEMPT_NEED_RESCHED))
+		return false;
+	if (current_thread_info()->preempt_lazy_count)
+		return false;
+	return test_thread_flag(TIF_NEED_RESCHED_LAZY);
+#else
+	return false;
+#endif
 }
 
 static inline bool should_resched(int preempt_offset)
 {
+#ifdef CONFIG_PREEMPT_LAZY
+	u64 pc = READ_ONCE(current_thread_info()->preempt_count);
+	if (pc == preempt_offset)
+		return true;
+
+	if ((pc & ~PREEMPT_NEED_RESCHED) != preempt_offset)
+		return false;
+
+	if (current_thread_info()->preempt_lazy_count)
+		return false;
+	return test_thread_flag(TIF_NEED_RESCHED_LAZY);
+#else
 	u64 pc = READ_ONCE(current_thread_info()->preempt_count);
 	return pc == preempt_offset;
+#endif
 }
 
 #ifdef CONFIG_PREEMPTION
 void preempt_schedule(void);
+#ifdef CONFIG_PREEMPT_RT
+void preempt_schedule_lock(void);
+#endif
 #define __preempt_schedule() preempt_schedule()
 void preempt_schedule_notrace(void);
 #define __preempt_schedule_notrace() preempt_schedule_notrace()
@ arch/arm64/include/asm/spinlock_types.h:8 @
 #ifndef __ASM_SPINLOCK_TYPES_H
 #define __ASM_SPINLOCK_TYPES_H
 
-#if !defined(__LINUX_SPINLOCK_TYPES_H) && !defined(__ASM_SPINLOCK_H)
-# error "please don't include this file directly"
-#endif
-
 #include <asm-generic/qspinlock_types.h>
 #include <asm-generic/qrwlock_types.h>
 
@ arch/arm64/include/asm/thread_info.h:32 @ struct thread_info {
 #ifdef CONFIG_ARM64_SW_TTBR0_PAN
 	u64			ttbr0;		/* saved TTBR0_EL1 */
 #endif
+	int			preempt_lazy_count;	/* 0 => preemptable, <0 => bug */
 	union {
 		u64		preempt_count;	/* 0 => preemptible, <0 => bug */
 		struct {
@ arch/arm64/include/asm/thread_info.h:72 @ void arch_release_task_struct(struct task_struct *tsk);
 #define TIF_UPROBE		4	/* uprobe breakpoint or singlestep */
 #define TIF_FSCHECK		5	/* Check FS is USER_DS on return */
 #define TIF_MTE_ASYNC_FAULT	6	/* MTE Asynchronous Tag Check Fault */
+#define TIF_NEED_RESCHED_LAZY	7
 #define TIF_SYSCALL_TRACE	8	/* syscall trace active */
 #define TIF_SYSCALL_AUDIT	9	/* syscall auditing */
 #define TIF_SYSCALL_TRACEPOINT	10	/* syscall tracepoint for ftrace */
@ arch/arm64/include/asm/thread_info.h:103 @ void arch_release_task_struct(struct task_struct *tsk);
 #define _TIF_32BIT		(1 << TIF_32BIT)
 #define _TIF_SVE		(1 << TIF_SVE)
 #define _TIF_MTE_ASYNC_FAULT	(1 << TIF_MTE_ASYNC_FAULT)
+#define _TIF_NEED_RESCHED_LAZY	(1 << TIF_NEED_RESCHED_LAZY)
 
 #define _TIF_WORK_MASK		(_TIF_NEED_RESCHED | _TIF_SIGPENDING | \
 				 _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE | \
-				 _TIF_UPROBE | _TIF_FSCHECK | _TIF_MTE_ASYNC_FAULT)
+				 _TIF_UPROBE | _TIF_FSCHECK | _TIF_MTE_ASYNC_FAULT | \
+				 _TIF_NEED_RESCHED_LAZY)
 
+#define _TIF_NEED_RESCHED_MASK	(_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY)
 #define _TIF_SYSCALL_WORK	(_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
 				 _TIF_SYSCALL_TRACEPOINT | _TIF_SECCOMP | \
 				 _TIF_SYSCALL_EMU)
@ arch/arm64/kernel/asm-offsets.c:33 @ int main(void)
   BLANK();
   DEFINE(TSK_TI_FLAGS,		offsetof(struct task_struct, thread_info.flags));
   DEFINE(TSK_TI_PREEMPT,	offsetof(struct task_struct, thread_info.preempt_count));
+  DEFINE(TSK_TI_PREEMPT_LAZY,	offsetof(struct task_struct, thread_info.preempt_lazy_count));
   DEFINE(TSK_TI_ADDR_LIMIT,	offsetof(struct task_struct, thread_info.addr_limit));
 #ifdef CONFIG_ARM64_SW_TTBR0_PAN
   DEFINE(TSK_TI_TTBR0,		offsetof(struct task_struct, thread_info.ttbr0));
@ arch/arm64/kernel/entry.S:518 @ alternative_if ARM64_HAS_IRQ_PRIO_MASKING
 	mrs	x0, daif
 	orr	x24, x24, x0
 alternative_else_nop_endif
-	cbnz	x24, 1f				// preempt count != 0 || NMI return path
-	bl	arm64_preempt_schedule_irq	// irq en/disable is done inside
+
+	cbz     x24, 1f                                 // (need_resched + count) == 0
+	cbnz    w24, 2f                                 // count != 0
+
+	ldr     w24, [tsk, #TSK_TI_PREEMPT_LAZY]        // get preempt lazy count
+	cbnz    w24, 2f                                 // preempt lazy count != 0
+
+	ldr     x0, [tsk, #TSK_TI_FLAGS]                // get flags
+	tbz     x0, #TIF_NEED_RESCHED_LAZY, 2f          // needs rescheduling?
 1:
+	bl      arm64_preempt_schedule_irq              // irq en/disable is done inside
+2:
 #endif
 
 	mov	x0, sp
@ arch/arm64/kernel/fpsimd.c:229 @ static void sve_free(struct task_struct *task)
 	__sve_free(task);
 }
 
+static void *sve_free_atomic(struct task_struct *task)
+{
+	void *sve_state = task->thread.sve_state;
+
+	WARN_ON(test_tsk_thread_flag(task, TIF_SVE));
+
+	task->thread.sve_state = NULL;
+	return sve_state;
+}
+
 /*
  * TIF_SVE controls whether a task can use SVE without trapping while
  * in userspace, and also the way a task's FPSIMD/SVE state is stored
@ arch/arm64/kernel/fpsimd.c:1035 @ void fpsimd_thread_switch(struct task_struct *next)
 void fpsimd_flush_thread(void)
 {
 	int vl, supported_vl;
+	void *mem = NULL;
 
 	if (!system_supports_fpsimd())
 		return;
@ arch/arm64/kernel/fpsimd.c:1048 @ void fpsimd_flush_thread(void)
 
 	if (system_supports_sve()) {
 		clear_thread_flag(TIF_SVE);
-		sve_free(current);
+		mem = sve_free_atomic(current);
 
 		/*
 		 * Reset the task vector length as required.
@ arch/arm64/kernel/fpsimd.c:1082 @ void fpsimd_flush_thread(void)
 	}
 
 	put_cpu_fpsimd_context();
+	kfree(mem);
 }
 
 /*
@ arch/arm64/kernel/signal.c:922 @ asmlinkage void do_notify_resume(struct pt_regs *regs,
 		/* Check valid user FS if needed */
 		addr_limit_user_check();
 
-		if (thread_flags & _TIF_NEED_RESCHED) {
+		if (thread_flags & _TIF_NEED_RESCHED_MASK) {
 			/* Unmask Debug and SError for the next task */
 			local_daif_restore(DAIF_PROCCTX_NOIRQ);
 
@ arch/arm64/kvm/arm.c:711 @ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
 		 * involves poking the GIC, which must be done in a
 		 * non-preemptible context.
 		 */
-		preempt_disable();
+		migrate_disable();
 
 		kvm_pmu_flush_hwstate(vcpu);
 
@ arch/arm64/kvm/arm.c:760 @ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
 				kvm_timer_sync_user(vcpu);
 			kvm_vgic_sync_hwstate(vcpu);
 			local_irq_enable();
-			preempt_enable();
+			migrate_enable();
 			continue;
 		}
 
@ arch/arm64/kvm/arm.c:832 @ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
 		/* Exit types that need handling before we can be preempted */
 		handle_exit_early(vcpu, ret);
 
-		preempt_enable();
+		migrate_enable();
 
 		/*
 		 * The ARMv8 architecture doesn't give the hypervisor
@ arch/csky/Kconfig:289 @ config NR_CPUS
 config HIGHMEM
 	bool "High Memory Support"
 	depends on !CPU_CK610
+	select KMAP_LOCAL
 	default y
 
 config FORCE_MAX_ZONEORDER
@ arch/csky/include/asm/fixmap.h:11 @
 #include <asm/memory.h>
 #ifdef CONFIG_HIGHMEM
 #include <linux/threads.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
 #endif
 
 enum fixed_addresses {
@ arch/csky/include/asm/fixmap.h:20 @ enum fixed_addresses {
 #endif
 #ifdef CONFIG_HIGHMEM
 	FIX_KMAP_BEGIN,
-	FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * NR_CPUS) - 1,
+	FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1,
 #endif
 	__end_of_fixed_addresses
 };
@ arch/csky/include/asm/highmem.h:12 @
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/uaccess.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
 #include <asm/cache.h>
 
 /* undef for production */
@ arch/csky/include/asm/highmem.h:35 @ extern pte_t *pkmap_page_table;
 
 #define ARCH_HAS_KMAP_FLUSH_TLB
 extern void kmap_flush_tlb(unsigned long addr);
-extern void *kmap_atomic_pfn(unsigned long pfn);
 
 #define flush_cache_kmaps() do {} while (0)
 
+#define arch_kmap_local_post_map(vaddr, pteval)	kmap_flush_tlb(vaddr)
+#define arch_kmap_local_post_unmap(vaddr)	kmap_flush_tlb(vaddr)
+
 extern void kmap_init(void);
 
 #endif /* __KERNEL__ */
@ arch/csky/mm/highmem.c:12 @
 #include <asm/tlbflush.h>
 #include <asm/cacheflush.h>
 
-static pte_t *kmap_pte;
-
 unsigned long highstart_pfn, highend_pfn;
 
 void kmap_flush_tlb(unsigned long addr)
@ arch/csky/mm/highmem.c:20 @ void kmap_flush_tlb(unsigned long addr)
 }
 EXPORT_SYMBOL(kmap_flush_tlb);
 
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
-	unsigned long vaddr;
-	int idx, type;
-
-	type = kmap_atomic_idx_push();
-	idx = type + KM_TYPE_NR*smp_processor_id();
-	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-#ifdef CONFIG_DEBUG_HIGHMEM
-	BUG_ON(!pte_none(*(kmap_pte - idx)));
-#endif
-	set_pte(kmap_pte-idx, mk_pte(page, prot));
-	flush_tlb_one((unsigned long)vaddr);
-
-	return (void *)vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kvaddr)
-{
-	unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-	int idx;
-
-	if (vaddr < FIXADDR_START)
-		return;
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-	idx = KM_TYPE_NR*smp_processor_id() + kmap_atomic_idx();
-
-	BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
-
-	pte_clear(&init_mm, vaddr, kmap_pte - idx);
-	flush_tlb_one(vaddr);
-#else
-	(void) idx; /* to kill a warning */
-#endif
-	kmap_atomic_idx_pop();
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
-
-/*
- * This is the same as kmap_atomic() but can map memory that doesn't
- * have a struct page associated with it.
- */
-void *kmap_atomic_pfn(unsigned long pfn)
-{
-	unsigned long vaddr;
-	int idx, type;
-
-	pagefault_disable();
-
-	type = kmap_atomic_idx_push();
-	idx = type + KM_TYPE_NR*smp_processor_id();
-	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-	set_pte(kmap_pte-idx, pfn_pte(pfn, PAGE_KERNEL));
-	flush_tlb_one(vaddr);
-
-	return (void *) vaddr;
-}
-
-static void __init kmap_pages_init(void)
+void __init kmap_init(void)
 {
 	unsigned long vaddr;
 	pgd_t *pgd;
@ arch/csky/mm/highmem.c:37 @ static void __init kmap_pages_init(void)
 	pte = pte_offset_kernel(pmd, vaddr);
 	pkmap_page_table = pte;
 }
-
-void __init kmap_init(void)
-{
-	unsigned long vaddr;
-
-	kmap_pages_init();
-
-	vaddr = __fix_to_virt(FIX_KMAP_BEGIN);
-
-	kmap_pte = pte_offset_kernel((pmd_t *)pgd_offset_k(vaddr), vaddr);
-}
@ arch/hexagon/include/asm/spinlock_types.h:11 @
 #ifndef _ASM_SPINLOCK_TYPES_H
 #define _ASM_SPINLOCK_TYPES_H
 
-#ifndef __LINUX_SPINLOCK_TYPES_H
-# error "please don't include this file directly"
-#endif
-
 typedef struct {
 	volatile unsigned int lock;
 } arch_spinlock_t;
@ arch/ia64/include/asm/kmap_types.h:1 @
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_IA64_KMAP_TYPES_H
-#define _ASM_IA64_KMAP_TYPES_H
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-#define  __WITH_KM_FENCE
-#endif
-
-#include <asm-generic/kmap_types.h>
-
-#undef __WITH_KM_FENCE
-
-#endif /* _ASM_IA64_KMAP_TYPES_H */
@ arch/ia64/include/asm/spinlock_types.h:5 @
 #ifndef _ASM_IA64_SPINLOCK_TYPES_H
 #define _ASM_IA64_SPINLOCK_TYPES_H
 
-#ifndef __LINUX_SPINLOCK_TYPES_H
-# error "please don't include this file directly"
-#endif
-
 typedef struct {
 	volatile unsigned int lock;
 } arch_spinlock_t;
@ arch/ia64/kernel/time.c:141 @ void vtime_account_kernel(struct task_struct *tsk)
 	struct thread_info *ti = task_thread_info(tsk);
 	__u64 stime = vtime_delta(tsk);
 
-	if ((tsk->flags & PF_VCPU) && !irq_count())
+	if (tsk->flags & PF_VCPU)
 		ti->gtime += stime;
-	else if (hardirq_count())
-		ti->hardirq_time += stime;
-	else if (in_serving_softirq())
-		ti->softirq_time += stime;
 	else
 		ti->stime += stime;
 }
@ arch/ia64/kernel/time.c:155 @ void vtime_account_idle(struct task_struct *tsk)
 	ti->idle_time += vtime_delta(tsk);
 }
 
+void vtime_account_softirq(struct task_struct *tsk)
+{
+	struct thread_info *ti = task_thread_info(tsk);
+
+	ti->softirq_time += vtime_delta(tsk);
+}
+
+void vtime_account_hardirq(struct task_struct *tsk)
+{
+	struct thread_info *ti = task_thread_info(tsk);
+
+	ti->hardirq_time += vtime_delta(tsk);
+}
+
 #endif /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */
 
 static irqreturn_t
@ arch/microblaze/Kconfig:158 @ config XILINX_UNCACHED_SHADOW
 config HIGHMEM
 	bool "High memory support"
 	depends on MMU
+	select KMAP_LOCAL
 	help
 	  The address space of Microblaze processors is only 4 Gigabytes large
 	  and it has to accommodate user address space, kernel address
@ arch/microblaze/include/asm/fixmap.h:23 @
 #include <asm/page.h>
 #ifdef CONFIG_HIGHMEM
 #include <linux/threads.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
 #endif
 
 #define FIXADDR_TOP	((unsigned long)(-PAGE_SIZE))
@ arch/microblaze/include/asm/fixmap.h:50 @ enum fixed_addresses {
 	FIX_HOLE,
 #ifdef CONFIG_HIGHMEM
 	FIX_KMAP_BEGIN,	/* reserved pte's for temporary kernel mappings */
-	FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * num_possible_cpus()) - 1,
+	FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * num_possible_cpus()) - 1,
 #endif
 	__end_of_fixed_addresses
 };
@ arch/microblaze/include/asm/highmem.h:28 @
 #include <linux/uaccess.h>
 #include <asm/fixmap.h>
 
-extern pte_t *kmap_pte;
 extern pte_t *pkmap_page_table;
 
 /*
@ arch/microblaze/include/asm/highmem.h:54 @ extern pte_t *pkmap_page_table;
 
 #define flush_cache_kmaps()	{ flush_icache(); flush_dcache(); }
 
+#define arch_kmap_local_post_map(vaddr, pteval)	\
+	local_flush_tlb_page(NULL, vaddr);
+#define arch_kmap_local_post_unmap(vaddr)	\
+	local_flush_tlb_page(NULL, vaddr);
+
 #endif /* __KERNEL__ */
 
 #endif /* _ASM_HIGHMEM_H */
@ arch/microblaze/mm/Makefile:9 @
 obj-y := consistent.o init.o
 
 obj-$(CONFIG_MMU) += pgtable.o mmu_context.o fault.o
-obj-$(CONFIG_HIGHMEM) += highmem.o
@ arch/microblaze/mm/highmem.c:1 @
-// SPDX-License-Identifier: GPL-2.0
-/*
- * highmem.c: virtual kernel memory mappings for high memory
- *
- * PowerPC version, stolen from the i386 version.
- *
- * Used in CONFIG_HIGHMEM systems for memory pages which
- * are not addressable by direct kernel virtual addresses.
- *
- * Copyright (C) 1999 Gerhard Wichert, Siemens AG
- *		      Gerhard.Wichert@pdb.siemens.de
- *
- *
- * Redesigned the x86 32-bit VM architecture to deal with
- * up to 16 Terrabyte physical memory. With current x86 CPUs
- * we now support up to 64 Gigabytes physical RAM.
- *
- * Copyright (C) 1999 Ingo Molnar <mingo@redhat.com>
- *
- * Reworked for PowerPC by various contributors. Moved from
- * highmem.h by Benjamin Herrenschmidt (c) 2009 IBM Corp.
- */
-
-#include <linux/export.h>
-#include <linux/highmem.h>
-
-/*
- * The use of kmap_atomic/kunmap_atomic is discouraged - kmap/kunmap
- * gives a more generic (and caching) interface. But kmap_atomic can
- * be used in IRQ contexts, so in some (very limited) cases we need
- * it.
- */
-#include <asm/tlbflush.h>
-
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
-
-	unsigned long vaddr;
-	int idx, type;
-
-	type = kmap_atomic_idx_push();
-	idx = type + KM_TYPE_NR*smp_processor_id();
-	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-#ifdef CONFIG_DEBUG_HIGHMEM
-	BUG_ON(!pte_none(*(kmap_pte-idx)));
-#endif
-	set_pte_at(&init_mm, vaddr, kmap_pte-idx, mk_pte(page, prot));
-	local_flush_tlb_page(NULL, vaddr);
-
-	return (void *) vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kvaddr)
-{
-	unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-	int type;
-	unsigned int idx;
-
-	if (vaddr < __fix_to_virt(FIX_KMAP_END))
-		return;
-
-	type = kmap_atomic_idx();
-
-	idx = type + KM_TYPE_NR * smp_processor_id();
-#ifdef CONFIG_DEBUG_HIGHMEM
-	BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
-#endif
-	/*
-	 * force other mappings to Oops if they'll try to access
-	 * this pte without first remap it
-	 */
-	pte_clear(&init_mm, vaddr, kmap_pte-idx);
-	local_flush_tlb_page(NULL, vaddr);
-
-	kmap_atomic_idx_pop();
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
@ arch/microblaze/mm/init.c:52 @ unsigned long lowmem_size;
 EXPORT_SYMBOL(min_low_pfn);
 EXPORT_SYMBOL(max_low_pfn);
 
-#ifdef CONFIG_HIGHMEM
-pte_t *kmap_pte;
-EXPORT_SYMBOL(kmap_pte);
-
 static void __init highmem_init(void)
 {
 	pr_debug("%x\n", (u32)PKMAP_BASE);
 	map_page(PKMAP_BASE, 0, 0);	/* XXX gross */
 	pkmap_page_table = virt_to_kpte(PKMAP_BASE);
-
-	kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
 }
 
 static void highmem_setup(void)
@ arch/mips/Kconfig:2729 @ config WAR_MIPS34K_MISSED_ITLB
 config HIGHMEM
 	bool "High Memory Support"
 	depends on 32BIT && CPU_SUPPORTS_HIGHMEM && SYS_SUPPORTS_HIGHMEM && !CPU_MIPS32_3_5_EVA
+	select KMAP_LOCAL
 
 config CPU_SUPPORTS_HIGHMEM
 	bool
@ arch/mips/include/asm/fixmap.h:20 @
 #include <spaces.h>
 #ifdef CONFIG_HIGHMEM
 #include <linux/threads.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
 #endif
 
 /*
@ arch/mips/include/asm/fixmap.h:55 @ enum fixed_addresses {
 #ifdef CONFIG_HIGHMEM
 	/* reserved pte's for temporary kernel mappings */
 	FIX_KMAP_BEGIN = FIX_CMAP_END + 1,
-	FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1,
+	FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1,
 #endif
 	__end_of_fixed_addresses
 };
@ arch/mips/include/asm/highmem.h:27 @
 #include <linux/interrupt.h>
 #include <linux/uaccess.h>
 #include <asm/cpu-features.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
 
 /* declarations for highmem.c */
 extern unsigned long highstart_pfn, highend_pfn;
@ arch/mips/include/asm/highmem.h:51 @ extern pte_t *pkmap_page_table;
 
 #define ARCH_HAS_KMAP_FLUSH_TLB
 extern void kmap_flush_tlb(unsigned long addr);
-extern void *kmap_atomic_pfn(unsigned long pfn);
 
 #define flush_cache_kmaps()	BUG_ON(cpu_has_dc_aliases)
 
-extern void kmap_init(void);
+#define arch_kmap_local_post_map(vaddr, pteval)	local_flush_tlb_one(vaddr)
+#define arch_kmap_local_post_unmap(vaddr)	local_flush_tlb_one(vaddr)
 
 #endif /* __KERNEL__ */
 
@ arch/mips/include/asm/kmap_types.h:1 @
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_KMAP_TYPES_H
-#define _ASM_KMAP_TYPES_H
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-#define	 __WITH_KM_FENCE
-#endif
-
-#include <asm-generic/kmap_types.h>
-
-#undef __WITH_KM_FENCE
-
-#endif
@ arch/mips/kernel/crash_dump.c:8 @
 #include <linux/uaccess.h>
 #include <linux/slab.h>
 
-static void *kdump_buf_page;
-
 /**
  * copy_oldmem_page - copy one page from "oldmem"
  * @pfn: page frame number to be copied
@ arch/mips/kernel/crash_dump.c:18 @ static void *kdump_buf_page;
  * @userbuf: if set, @buf is in user address space, use copy_to_user(),
  *	otherwise @buf is in kernel address space, use memcpy().
  *
- * Copy a page from "oldmem". For this page, there is no pte mapped
+ * Copy a page from "oldmem". For this page, there might be no pte mapped
  * in the current kernel.
- *
- * Calling copy_to_user() in atomic context is not desirable. Hence first
- * copying the data to a pre-allocated kernel page and then copying to user
- * space in non-atomic context.
  */
-ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
-			 size_t csize, unsigned long offset, int userbuf)
+ssize_t copy_oldmem_page(unsigned long pfn, char *buf, size_t csize,
+			 unsigned long offset, int userbuf)
 {
 	void  *vaddr;
 
 	if (!csize)
 		return 0;
 
-	vaddr = kmap_atomic_pfn(pfn);
+	vaddr = kmap_local_pfn(pfn);
 
 	if (!userbuf) {
-		memcpy(buf, (vaddr + offset), csize);
-		kunmap_atomic(vaddr);
+		memcpy(buf, vaddr + offset, csize);
 	} else {
-		if (!kdump_buf_page) {
-			pr_warn("Kdump: Kdump buffer page not allocated\n");
-
-			return -EFAULT;
-		}
-		copy_page(kdump_buf_page, vaddr);
-		kunmap_atomic(vaddr);
-		if (copy_to_user(buf, (kdump_buf_page + offset), csize))
-			return -EFAULT;
+		if (copy_to_user(buf, vaddr + offset, csize))
+			csize = -EFAULT;
 	}
 
 	return csize;
 }
-
-static int __init kdump_buf_page_init(void)
-{
-	int ret = 0;
-
-	kdump_buf_page = kmalloc(PAGE_SIZE, GFP_KERNEL);
-	if (!kdump_buf_page) {
-		pr_warn("Kdump: Failed to allocate kdump buffer page\n");
-		ret = -ENOMEM;
-	}
-
-	return ret;
-}
-arch_initcall(kdump_buf_page_init);
@ arch/mips/mm/highmem.c:11 @
 #include <asm/fixmap.h>
 #include <asm/tlbflush.h>
 
-static pte_t *kmap_pte;
-
 unsigned long highstart_pfn, highend_pfn;
 
 void kmap_flush_tlb(unsigned long addr)
@ arch/mips/mm/highmem.c:18 @ void kmap_flush_tlb(unsigned long addr)
 	flush_tlb_one(addr);
 }
 EXPORT_SYMBOL(kmap_flush_tlb);
-
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
-	unsigned long vaddr;
-	int idx, type;
-
-	type = kmap_atomic_idx_push();
-	idx = type + KM_TYPE_NR*smp_processor_id();
-	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-#ifdef CONFIG_DEBUG_HIGHMEM
-	BUG_ON(!pte_none(*(kmap_pte - idx)));
-#endif
-	set_pte(kmap_pte-idx, mk_pte(page, prot));
-	local_flush_tlb_one((unsigned long)vaddr);
-
-	return (void*) vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kvaddr)
-{
-	unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-	int type __maybe_unused;
-
-	if (vaddr < FIXADDR_START)
-		return;
-
-	type = kmap_atomic_idx();
-#ifdef CONFIG_DEBUG_HIGHMEM
-	{
-		int idx = type + KM_TYPE_NR * smp_processor_id();
-
-		BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
-
-		/*
-		 * force other mappings to Oops if they'll try to access
-		 * this pte without first remap it
-		 */
-		pte_clear(&init_mm, vaddr, kmap_pte-idx);
-		local_flush_tlb_one(vaddr);
-	}
-#endif
-	kmap_atomic_idx_pop();
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
-
-/*
- * This is the same as kmap_atomic() but can map memory that doesn't
- * have a struct page associated with it.
- */
-void *kmap_atomic_pfn(unsigned long pfn)
-{
-	unsigned long vaddr;
-	int idx, type;
-
-	preempt_disable();
-	pagefault_disable();
-
-	type = kmap_atomic_idx_push();
-	idx = type + KM_TYPE_NR*smp_processor_id();
-	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-	set_pte(kmap_pte-idx, pfn_pte(pfn, PAGE_KERNEL));
-	flush_tlb_one(vaddr);
-
-	return (void*) vaddr;
-}
-
-void __init kmap_init(void)
-{
-	unsigned long kmap_vstart;
-
-	/* cache the first kmap pte */
-	kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
-	kmap_pte = virt_to_kpte(kmap_vstart);
-}
@ arch/mips/mm/init.c:39 @
 #include <asm/cachectl.h>
 #include <asm/cpu.h>
 #include <asm/dma.h>
-#include <asm/kmap_types.h>
 #include <asm/maar.h>
 #include <asm/mmu_context.h>
 #include <asm/sections.h>
@ arch/mips/mm/init.c:404 @ void __init paging_init(void)
 
 	pagetable_init();
 
-#ifdef CONFIG_HIGHMEM
-	kmap_init();
-#endif
 #ifdef CONFIG_ZONE_DMA
 	max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
 #endif
@ arch/nds32/Kconfig.cpu:160 @ config HW_SUPPORT_UNALIGNMENT_ACCESS
 config HIGHMEM
 	bool "High Memory Support"
 	depends on MMU && !CPU_CACHE_ALIASING
+	select KMAP_LOCAL
 	help
 	  The address space of Andes processors is only 4 Gigabytes large
 	  and it has to accommodate user address space, kernel address
@ arch/nds32/include/asm/fixmap.h:9 @
 
 #ifdef CONFIG_HIGHMEM
 #include <linux/threads.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
 #endif
 
 enum fixed_addresses {
@ arch/nds32/include/asm/fixmap.h:17 @ enum fixed_addresses {
 	FIX_KMAP_RESERVED,
 	FIX_KMAP_BEGIN,
 #ifdef CONFIG_HIGHMEM
-	FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * NR_CPUS),
+	FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1,
 #endif
 	FIX_EARLYCON_MEM_BASE,
 	__end_of_fixed_addresses
@ arch/nds32/include/asm/highmem.h:8 @
 #define _ASM_HIGHMEM_H
 
 #include <asm/proc-fns.h>
-#include <asm/kmap_types.h>
 #include <asm/fixmap.h>
 
 /*
@ arch/nds32/include/asm/highmem.h:47 @ extern pte_t *pkmap_page_table;
 extern void kmap_init(void);
 
 /*
- * The following functions are already defined by <linux/highmem.h>
- * when CONFIG_HIGHMEM is not set.
+ * FIXME: The below looks broken vs. a kmap_atomic() in task context which
+ * is interupted and another kmap_atomic() happens in interrupt context.
+ * But what do I know about nds32. -- tglx
  */
-#ifdef CONFIG_HIGHMEM
-extern void *kmap_atomic_pfn(unsigned long pfn);
-#endif
+#define arch_kmap_local_post_map(vaddr, pteval)			\
+	do {							\
+		__nds32__tlbop_inv(vaddr);			\
+		__nds32__mtsr_dsb(vaddr, NDS32_SR_TLB_VPN);	\
+		__nds32__tlbop_rwr(pteval);			\
+		__nds32__isb();					\
+	} while (0)
+
+#define arch_kmap_local_pre_unmap(vaddr)			\
+	do {							\
+		__nds32__tlbop_inv(vaddr);			\
+		__nds32__isb();					\
+	} while (0)
 
 #endif
@ arch/nds32/mm/Makefile:6 @ obj-y				:= extable.o tlb.o fault.o init.o mmap.o \
                                    mm-nds32.o cacheflush.o proc.o
 
 obj-$(CONFIG_ALIGNMENT_TRAP)	+= alignment.o
-obj-$(CONFIG_HIGHMEM)           += highmem.o
 
 ifdef CONFIG_FUNCTION_TRACER
 CFLAGS_REMOVE_proc.o     = $(CC_FLAGS_FTRACE)
@ arch/nds32/mm/highmem.c:1 @
-// SPDX-License-Identifier: GPL-2.0
-// Copyright (C) 2005-2017 Andes Technology Corporation
-
-#include <linux/export.h>
-#include <linux/highmem.h>
-#include <linux/sched.h>
-#include <linux/smp.h>
-#include <linux/interrupt.h>
-#include <linux/memblock.h>
-#include <asm/fixmap.h>
-#include <asm/tlbflush.h>
-
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
-	unsigned int idx;
-	unsigned long vaddr, pte;
-	int type;
-	pte_t *ptep;
-
-	type = kmap_atomic_idx_push();
-
-	idx = type + KM_TYPE_NR * smp_processor_id();
-	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-	pte = (page_to_pfn(page) << PAGE_SHIFT) | prot;
-	ptep = pte_offset_kernel(pmd_off_k(vaddr), vaddr);
-	set_pte(ptep, pte);
-
-	__nds32__tlbop_inv(vaddr);
-	__nds32__mtsr_dsb(vaddr, NDS32_SR_TLB_VPN);
-	__nds32__tlbop_rwr(pte);
-	__nds32__isb();
-	return (void *)vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kvaddr)
-{
-	if (kvaddr >= (void *)FIXADDR_START) {
-		unsigned long vaddr = (unsigned long)kvaddr;
-		pte_t *ptep;
-		kmap_atomic_idx_pop();
-		__nds32__tlbop_inv(vaddr);
-		__nds32__isb();
-		ptep = pte_offset_kernel(pmd_off_k(vaddr), vaddr);
-		set_pte(ptep, 0);
-	}
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
@ arch/openrisc/mm/init.c:36 @
 #include <asm/io.h>
 #include <asm/tlb.h>
 #include <asm/mmu_context.h>
-#include <asm/kmap_types.h>
 #include <asm/fixmap.h>
 #include <asm/tlbflush.h>
 #include <asm/sections.h>
@ arch/openrisc/mm/ioremap.c:18 @
 #include <linux/io.h>
 #include <linux/pgtable.h>
 #include <asm/pgalloc.h>
-#include <asm/kmap_types.h>
 #include <asm/fixmap.h>
 #include <asm/bug.h>
 #include <linux/sched.h>
@ arch/parisc/include/asm/hardirq.h:35 @ typedef struct {
 DECLARE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat);
 
 #define __ARCH_IRQ_STAT
-#define __IRQ_STAT(cpu, member) (irq_stat[cpu].member)
 #define inc_irq_stat(member)	this_cpu_inc(irq_stat.member)
 #define __inc_irq_stat(member)	__this_cpu_inc(irq_stat.member)
 #define ack_bad_irq(irq) WARN(1, "unexpected IRQ trap at vector %02x\n", irq)
@ arch/parisc/include/asm/kmap_types.h:1 @
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_KMAP_TYPES_H
-#define _ASM_KMAP_TYPES_H
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-#define  __WITH_KM_FENCE
-#endif
-
-#include <asm-generic/kmap_types.h>
-
-#undef __WITH_KM_FENCE
-
-#endif
@ arch/powerpc/Kconfig:149 @ config PPC
 	select ARCH_MIGHT_HAVE_PC_SERIO
 	select ARCH_OPTIONAL_KERNEL_RWX		if ARCH_HAS_STRICT_KERNEL_RWX
 	select ARCH_SUPPORTS_ATOMIC_RMW
+	select ARCH_SUPPORTS_RT if HAVE_POSIX_CPU_TIMERS_TASK_WORK
 	select ARCH_USE_BUILTIN_BSWAP
 	select ARCH_USE_CMPXCHG_LOCKREF		if PPC64
 	select ARCH_USE_QUEUED_RWLOCKS		if PPC_QUEUED_SPINLOCKS
@ arch/powerpc/Kconfig:234 @ config PPC
 	select HAVE_HARDLOCKUP_DETECTOR_PERF	if PERF_EVENTS && HAVE_PERF_EVENTS_NMI && !HAVE_HARDLOCKUP_DETECTOR_ARCH
 	select HAVE_PERF_REGS
 	select HAVE_PERF_USER_STACK_DUMP
+	select HAVE_PREEMPT_LAZY
 	select MMU_GATHER_RCU_TABLE_FREE
 	select MMU_GATHER_PAGE_SIZE
 	select HAVE_REGS_AND_STACK_ACCESS_API
@ arch/powerpc/Kconfig:242 @ config PPC
 	select HAVE_SYSCALL_TRACEPOINTS
 	select HAVE_VIRT_CPU_ACCOUNTING
 	select HAVE_IRQ_TIME_ACCOUNTING
+	select HAVE_POSIX_CPU_TIMERS_TASK_WORK  if !KVM
 	select HAVE_RSEQ
 	select IOMMU_HELPER			if PPC64
 	select IRQ_DOMAIN
@ arch/powerpc/Kconfig:416 @ menu "Kernel options"
 config HIGHMEM
 	bool "High memory support"
 	depends on PPC32
+	select KMAP_LOCAL
 
 source "kernel/Kconfig.hz"
 
@ arch/powerpc/include/asm/cmpxchg.h:8 @
 #ifdef __KERNEL__
 #include <linux/compiler.h>
 #include <asm/synch.h>
-#include <linux/bug.h>
+#include <linux/bits.h>
 
 #ifdef __BIG_ENDIAN
 #define BITOFF_CAL(size, off)	((sizeof(u32) - size - off) * BITS_PER_BYTE)
@ arch/powerpc/include/asm/fixmap.h:23 @
 #include <asm/page.h>
 #ifdef CONFIG_HIGHMEM
 #include <linux/threads.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
 #endif
 
 #ifdef CONFIG_PPC64
@ arch/powerpc/include/asm/fixmap.h:64 @ enum fixed_addresses {
 	FIX_EARLY_DEBUG_BASE = FIX_EARLY_DEBUG_TOP+(ALIGN(SZ_128K, PAGE_SIZE)/PAGE_SIZE)-1,
 #ifdef CONFIG_HIGHMEM
 	FIX_KMAP_BEGIN,	/* reserved pte's for temporary kernel mappings */
-	FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1,
+	FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1,
 #endif
 #ifdef CONFIG_PPC_8xx
 	/* For IMMR we need an aligned 512K area */
@ arch/powerpc/include/asm/highmem.h:27 @
 #ifdef __KERNEL__
 
 #include <linux/interrupt.h>
-#include <asm/kmap_types.h>
 #include <asm/cacheflush.h>
 #include <asm/page.h>
 #include <asm/fixmap.h>
 
-extern pte_t *kmap_pte;
 extern pte_t *pkmap_page_table;
 
 /*
@ arch/powerpc/include/asm/highmem.h:61 @ extern pte_t *pkmap_page_table;
 
 #define flush_cache_kmaps()	flush_cache_all()
 
+#define arch_kmap_local_post_map(vaddr, pteval)	\
+	local_flush_tlb_page(NULL, vaddr)
+#define arch_kmap_local_post_unmap(vaddr)	\
+	local_flush_tlb_page(NULL, vaddr)
+
 #endif /* __KERNEL__ */
 
 #endif /* _ASM_HIGHMEM_H */
@ arch/powerpc/include/asm/kmap_types.h:1 @
-/* SPDX-License-Identifier: GPL-2.0-or-later */
-#ifndef _ASM_POWERPC_KMAP_TYPES_H
-#define _ASM_POWERPC_KMAP_TYPES_H
-
-#ifdef __KERNEL__
-
-/*
- */
-
-#define KM_TYPE_NR 16
-
-#endif	/* __KERNEL__ */
-#endif	/* _ASM_POWERPC_KMAP_TYPES_H */
@ arch/powerpc/include/asm/simple_spinlock_types.h:5 @
 #ifndef _ASM_POWERPC_SIMPLE_SPINLOCK_TYPES_H
 #define _ASM_POWERPC_SIMPLE_SPINLOCK_TYPES_H
 
-#ifndef __LINUX_SPINLOCK_TYPES_H
+#if !defined(__LINUX_SPINLOCK_TYPES_H) && !defined(__LINUX_RT_MUTEX_H)
 # error "please don't include this file directly"
 #endif
 
@ arch/powerpc/include/asm/spinlock_types.h:5 @
 #ifndef _ASM_POWERPC_SPINLOCK_TYPES_H
 #define _ASM_POWERPC_SPINLOCK_TYPES_H
 
-#ifndef __LINUX_SPINLOCK_TYPES_H
-# error "please don't include this file directly"
-#endif
-
 #ifdef CONFIG_PPC_QUEUED_SPINLOCKS
 #include <asm-generic/qspinlock_types.h>
 #include <asm-generic/qrwlock_types.h>
@ arch/powerpc/include/asm/stackprotector.h:27 @ static __always_inline void boot_init_stack_canary(void)
 	unsigned long canary;
 
 	/* Try to get a semi random initial value. */
+#ifdef CONFIG_PREEMPT_RT
+	canary = (unsigned long)&canary;
+#else
 	canary = get_random_canary();
+#endif
 	canary ^= mftb();
 	canary ^= LINUX_VERSION_CODE;
 	canary &= CANARY_MASK;
@ arch/powerpc/include/asm/thread_info.h:51 @
 struct thread_info {
 	int		preempt_count;		/* 0 => preemptable,
 						   <0 => BUG */
+	int             preempt_lazy_count;	/* 0 => preemptable,
+						   <0 => BUG */
 	unsigned long	local_flags;		/* private flags for thread */
 #ifdef CONFIG_LIVEPATCH
 	unsigned long *livepatch_sp;
@ arch/powerpc/include/asm/thread_info.h:102 @ void arch_setup_new_exec(void);
 #define TIF_SINGLESTEP		8	/* singlestepping active */
 #define TIF_NOHZ		9	/* in adaptive nohz mode */
 #define TIF_SECCOMP		10	/* secure computing */
-#define TIF_RESTOREALL		11	/* Restore all regs (implies NOERROR) */
-#define TIF_NOERROR		12	/* Force successful syscall return */
+
+#define TIF_NEED_RESCHED_LAZY	11	/* lazy rescheduling necessary */
+#define TIF_SYSCALL_TRACEPOINT	12	/* syscall tracepoint instrumentation */
+
 #define TIF_NOTIFY_RESUME	13	/* callback before returning to user */
 #define TIF_UPROBE		14	/* breakpointed or single-stepping */
-#define TIF_SYSCALL_TRACEPOINT	15	/* syscall tracepoint instrumentation */
 #define TIF_EMULATE_STACK_STORE	16	/* Is an instruction emulation
 						for stack store? */
 #define TIF_MEMDIE		17	/* is terminating due to OOM killer */
@ arch/powerpc/include/asm/thread_info.h:116 @ void arch_setup_new_exec(void);
 #endif
 #define TIF_POLLING_NRFLAG	19	/* true if poll_idle() is polling TIF_NEED_RESCHED */
 #define TIF_32BIT		20	/* 32 bit binary */
+#define TIF_RESTOREALL		21	/* Restore all regs (implies NOERROR) */
+#define TIF_NOERROR		22	/* Force successful syscall return */
+
 
 /* as above, but as bit values */
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
@ arch/powerpc/include/asm/thread_info.h:138 @ void arch_setup_new_exec(void);
 #define _TIF_SYSCALL_TRACEPOINT	(1<<TIF_SYSCALL_TRACEPOINT)
 #define _TIF_EMULATE_STACK_STORE	(1<<TIF_EMULATE_STACK_STORE)
 #define _TIF_NOHZ		(1<<TIF_NOHZ)
+#define _TIF_NEED_RESCHED_LAZY	(1<<TIF_NEED_RESCHED_LAZY)
 #define _TIF_SYSCALL_EMU	(1<<TIF_SYSCALL_EMU)
 #define _TIF_SYSCALL_DOTRACE	(_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
 				 _TIF_SECCOMP | _TIF_SYSCALL_TRACEPOINT | \
@ arch/powerpc/include/asm/thread_info.h:146 @ void arch_setup_new_exec(void);
 
 #define _TIF_USER_WORK_MASK	(_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
 				 _TIF_NOTIFY_RESUME | _TIF_UPROBE | \
-				 _TIF_RESTORE_TM | _TIF_PATCH_PENDING)
+				 _TIF_RESTORE_TM | _TIF_PATCH_PENDING | \
+				 _TIF_NEED_RESCHED_LAZY)
 #define _TIF_PERSYSCALL_MASK	(_TIF_RESTOREALL|_TIF_NOERROR)
+#define _TIF_NEED_RESCHED_MASK	(_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY)
 
 /* Bits in local_flags */
 /* Don't move TLF_NAPPING without adjusting the code in entry_32.S */
@ arch/powerpc/kernel/asm-offsets.c:192 @ int main(void)
 	OFFSET(TI_FLAGS, thread_info, flags);
 	OFFSET(TI_LOCAL_FLAGS, thread_info, local_flags);
 	OFFSET(TI_PREEMPT, thread_info, preempt_count);
+	OFFSET(TI_PREEMPT_LAZY, thread_info, preempt_lazy_count);
 
 #ifdef CONFIG_PPC64
 	OFFSET(DCACHEL1BLOCKSIZE, ppc64_caches, l1d.block_size);
@ arch/powerpc/kernel/entry_32.S:417 @ ret_from_syscall:
 	mtmsr	r10
 	lwz	r9,TI_FLAGS(r2)
 	li	r8,-MAX_ERRNO
-	andi.	r0,r9,(_TIF_SYSCALL_DOTRACE|_TIF_SINGLESTEP|_TIF_USER_WORK_MASK|_TIF_PERSYSCALL_MASK)
+	lis	r0,(_TIF_SYSCALL_DOTRACE|_TIF_SINGLESTEP|_TIF_USER_WORK_MASK|_TIF_PERSYSCALL_MASK)@h
+	ori	r0,r0, (_TIF_SYSCALL_DOTRACE|_TIF_SINGLESTEP|_TIF_USER_WORK_MASK|_TIF_PERSYSCALL_MASK)@l
+	and.	r0,r9,r0
 	bne-	syscall_exit_work
 	cmplw	0,r3,r8
 	blt+	syscall_exit_cont
@ arch/powerpc/kernel/entry_32.S:535 @ syscall_dotrace:
 	b	syscall_dotrace_cont
 
 syscall_exit_work:
-	andi.	r0,r9,_TIF_RESTOREALL
+	andis.	r0,r9,_TIF_RESTOREALL@h
 	beq+	0f
 	REST_NVGPRS(r1)
 	b	2f
 0:	cmplw	0,r3,r8
 	blt+	1f
-	andi.	r0,r9,_TIF_NOERROR
+	andis.	r0,r9,_TIF_NOERROR@h
 	bne-	1f
 	lwz	r11,_CCR(r1)			/* Load CR */
 	neg	r3,r3
@ arch/powerpc/kernel/entry_32.S:550 @ syscall_exit_work:
 
 1:	stw	r6,RESULT(r1)	/* Save result */
 	stw	r3,GPR3(r1)	/* Update return value */
-2:	andi.	r0,r9,(_TIF_PERSYSCALL_MASK)
+2:	andis.	r0,r9,(_TIF_PERSYSCALL_MASK)@h
 	beq	4f
 
 	/* Clear per-syscall TIF flags if any are set.  */
 
-	li	r11,_TIF_PERSYSCALL_MASK
+	lis	r11,(_TIF_PERSYSCALL_MASK)@h
 	addi	r12,r2,TI_FLAGS
 3:	lwarx	r8,0,r12
 	andc	r8,r8,r11
@ arch/powerpc/kernel/entry_32.S:932 @ resume_kernel:
 	cmpwi	0,r0,0		/* if non-zero, just restore regs and return */
 	bne	restore_kuap
 	andi.	r8,r8,_TIF_NEED_RESCHED
+	bne+	1f
+	lwz	r0,TI_PREEMPT_LAZY(r2)
+	cmpwi	0,r0,0          /* if non-zero, just restore regs and return */
+	bne	restore_kuap
+	lwz	r0,TI_FLAGS(r2)
+	andi.	r0,r0,_TIF_NEED_RESCHED_LAZY
 	beq+	restore_kuap
+1:
 	lwz	r3,_MSR(r1)
 	andi.	r0,r3,MSR_EE	/* interrupts off? */
 	beq	restore_kuap	/* don't schedule if so */
@ arch/powerpc/kernel/entry_32.S:1260 @ global_dbcr0:
 #endif /* !(CONFIG_4xx || CONFIG_BOOKE) */
 
 do_work:			/* r10 contains MSR_KERNEL here */
-	andi.	r0,r9,_TIF_NEED_RESCHED
+	andi.	r0,r9,_TIF_NEED_RESCHED_MASK
 	beq	do_user_signal
 
 do_resched:			/* r10 contains MSR_KERNEL here */
@ arch/powerpc/kernel/entry_32.S:1279 @ recheck:
 	LOAD_REG_IMMEDIATE(r10,MSR_KERNEL)
 	mtmsr	r10		/* disable interrupts */
 	lwz	r9,TI_FLAGS(r2)
-	andi.	r0,r9,_TIF_NEED_RESCHED
+	andi.	r0,r9,_TIF_NEED_RESCHED_MASK
 	bne-	do_resched
 	andi.	r0,r9,_TIF_USER_WORK_MASK
 	beq	restore_user
@ arch/powerpc/kernel/exceptions-64e.S:1083 @ _GLOBAL(ret_from_except_lite)
 	li	r10, -1
 	mtspr	SPRN_DBSR,r10
 	b	restore
-1:	andi.	r0,r4,_TIF_NEED_RESCHED
+1:	andi.	r0,r4,_TIF_NEED_RESCHED_MASK
 	beq	2f
 	bl	restore_interrupts
 	SCHEDULE_USER
@ arch/powerpc/kernel/exceptions-64e.S:1135 @ resume_kernel:
 	bne-	0b
 1:
 
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPTION
 	/* Check if we need to preempt */
+	lwz	r8,TI_PREEMPT(r9)
+	cmpwi	0,r8,0		/* if non-zero, just restore regs and return */
+	bne	restore
 	andi.	r0,r4,_TIF_NEED_RESCHED
+	bne+	check_count
+
+	andi.	r0,r4,_TIF_NEED_RESCHED_LAZY
 	beq+	restore
+	lwz	r8,TI_PREEMPT_LAZY(r9)
+
 	/* Check that preempt_count() == 0 and interrupts are enabled */
-	lwz	r8,TI_PREEMPT(r9)
+check_count:
 	cmpwi	cr0,r8,0
 	bne	restore
 	ld	r0,SOFTE(r1)
@ arch/powerpc/kernel/exceptions-64e.S:1169 @ resume_kernel:
 	 * interrupted after loading SRR0/1.
 	 */
 	wrteei	0
-#endif /* CONFIG_PREEMPT */
+#endif /* CONFIG_PREEMPTION */
 
 restore:
 	/*
@ arch/powerpc/kernel/irq.c:756 @ void *mcheckirq_ctx[NR_CPUS] __read_mostly;
 void *softirq_ctx[NR_CPUS] __read_mostly;
 void *hardirq_ctx[NR_CPUS] __read_mostly;
 
+#ifndef CONFIG_PREEMPT_RT
 void do_softirq_own_stack(void)
 {
 	call_do_softirq(softirq_ctx[smp_processor_id()]);
 }
+#endif
 
 irq_hw_number_t virq_to_hw(unsigned int virq)
 {
@ arch/powerpc/kernel/misc_32.S:34 @
  * We store the saved ksp_limit in the unused part
  * of the STACK_FRAME_OVERHEAD
  */
+#ifndef CONFIG_PREEMPT_RT
 _GLOBAL(call_do_softirq)
 	mflr	r0
 	stw	r0,4(r1)
@ arch/powerpc/kernel/misc_32.S:50 @ _GLOBAL(call_do_softirq)
 	stw	r10,THREAD+KSP_LIMIT(r2)
 	mtlr	r0
 	blr
+#endif
 
 /*
  * void call_do_irq(struct pt_regs *regs, void *sp);
@ arch/powerpc/kernel/misc_64.S:30 @
 
 	.text
 
+#ifndef CONFIG_PREEMPT_RT
 _GLOBAL(call_do_softirq)
 	mflr	r0
 	std	r0,16(r1)
@ arch/powerpc/kernel/misc_64.S:41 @ _GLOBAL(call_do_softirq)
 	ld	r0,16(r1)
 	mtlr	r0
 	blr
+#endif
 
 _GLOBAL(call_do_irq)
 	mflr	r0
@ arch/powerpc/kernel/nvram_64.c:76 @ static const char *nvram_os_partitions[] = {
 };
 
 static void oops_to_nvram(struct kmsg_dumper *dumper,
-			  enum kmsg_dump_reason reason);
+			  enum kmsg_dump_reason reason,
+			  struct kmsg_dumper_iter *iter);
 
 static struct kmsg_dumper nvram_kmsg_dumper = {
 	.dump = oops_to_nvram
@ arch/powerpc/kernel/nvram_64.c:647 @ void __init nvram_init_oops_partition(int rtas_partition_exists)
  * partition.  If that's too much, go back and capture uncompressed text.
  */
 static void oops_to_nvram(struct kmsg_dumper *dumper,
-			  enum kmsg_dump_reason reason)
+			  enum kmsg_dump_reason reason,
+			  struct kmsg_dumper_iter *iter)
 {
 	struct oops_log_info *oops_hdr = (struct oops_log_info *)oops_buf;
 	static unsigned int oops_count = 0;
@ arch/powerpc/kernel/nvram_64.c:686 @ static void oops_to_nvram(struct kmsg_dumper *dumper,
 		return;
 
 	if (big_oops_buf) {
-		kmsg_dump_get_buffer(dumper, false,
+		kmsg_dump_get_buffer(iter, false,
 				     big_oops_buf, big_oops_buf_sz, &text_len);
 		rc = zip_oops(text_len);
 	}
 	if (rc != 0) {
-		kmsg_dump_rewind(dumper);
-		kmsg_dump_get_buffer(dumper, false,
+		kmsg_dump_rewind(iter);
+		kmsg_dump_get_buffer(iter, false,
 				     oops_data, oops_data_sz, &text_len);
 		err_type = ERR_TYPE_KERNEL_PANIC;
 		oops_hdr->version = cpu_to_be16(OOPS_HDR_VERSION);
@ arch/powerpc/kernel/syscall_64.c:196 @ notrace unsigned long syscall_exit_prepare(unsigned long r3,
 	ti_flags = READ_ONCE(*ti_flagsp);
 	while (unlikely(ti_flags & (_TIF_USER_WORK_MASK & ~_TIF_RESTORE_TM))) {
 		local_irq_enable();
-		if (ti_flags & _TIF_NEED_RESCHED) {
+		if (ti_flags & _TIF_NEED_RESCHED_MASK) {
 			schedule();
 		} else {
 			/*
@ arch/powerpc/kernel/syscall_64.c:280 @ notrace unsigned long interrupt_exit_user_prepare(struct pt_regs *regs, unsigned
 	ti_flags = READ_ONCE(*ti_flagsp);
 	while (unlikely(ti_flags & (_TIF_USER_WORK_MASK & ~_TIF_RESTORE_TM))) {
 		local_irq_enable(); /* returning to user: may enable */
-		if (ti_flags & _TIF_NEED_RESCHED) {
+		if (ti_flags & _TIF_NEED_RESCHED_MASK) {
 			schedule();
 		} else {
 			if (ti_flags & _TIF_SIGPENDING)
@ arch/powerpc/kernel/syscall_64.c:364 @ notrace unsigned long interrupt_exit_kernel_prepare(struct pt_regs *regs, unsign
 		/* Returning to a kernel context with local irqs enabled. */
 		WARN_ON_ONCE(!(regs->msr & MSR_EE));
 again:
-		if (IS_ENABLED(CONFIG_PREEMPT)) {
+		if (IS_ENABLED(CONFIG_PREEMPTION)) {
 			/* Return to preemptible kernel context */
 			if (unlikely(*ti_flagsp & _TIF_NEED_RESCHED)) {
 				if (preempt_count() == 0)
 					preempt_schedule_irq();
+			} else if (unlikely(*ti_flagsp & _TIF_NEED_RESCHED_LAZY)) {
+				if ((preempt_count() == 0) &&
+				    (current_thread_info()->preempt_lazy_count == 0))
+					preempt_schedule_irq();
 			}
 		}
 
@ arch/powerpc/kernel/time.c:315 @ static unsigned long vtime_delta_scaled(struct cpu_accounting_data *acct,
 	return stime_scaled;
 }
 
-static unsigned long vtime_delta(struct task_struct *tsk,
+static unsigned long vtime_delta(struct cpu_accounting_data *acct,
 				 unsigned long *stime_scaled,
 				 unsigned long *steal_time)
 {
 	unsigned long now, stime;
-	struct cpu_accounting_data *acct = get_accounting(tsk);
 
 	WARN_ON_ONCE(!irqs_disabled());
 
@ arch/powerpc/kernel/time.c:334 @ static unsigned long vtime_delta(struct task_struct *tsk,
 	return stime;
 }
 
+static void vtime_delta_kernel(struct cpu_accounting_data *acct,
+			       unsigned long *stime, unsigned long *stime_scaled)
+{
+	unsigned long steal_time;
+
+	*stime = vtime_delta(acct, stime_scaled, &steal_time);
+	*stime -= min(*stime, steal_time);
+	acct->steal_time += steal_time;
+}
+
 void vtime_account_kernel(struct task_struct *tsk)
 {
-	unsigned long stime, stime_scaled, steal_time;
 	struct cpu_accounting_data *acct = get_accounting(tsk);
+	unsigned long stime, stime_scaled;
 
-	stime = vtime_delta(tsk, &stime_scaled, &steal_time);
-
-	stime -= min(stime, steal_time);
-	acct->steal_time += steal_time;
+	vtime_delta_kernel(acct, &stime, &stime_scaled);
 
-	if ((tsk->flags & PF_VCPU) && !irq_count()) {
+	if (tsk->flags & PF_VCPU) {
 		acct->gtime += stime;
 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
 		acct->utime_scaled += stime_scaled;
 #endif
 	} else {
-		if (hardirq_count())
-			acct->hardirq_time += stime;
-		else if (in_serving_softirq())
-			acct->softirq_time += stime;
-		else
-			acct->stime += stime;
-
+		acct->stime += stime;
 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
 		acct->stime_scaled += stime_scaled;
 #endif
@ arch/powerpc/kernel/time.c:370 @ void vtime_account_idle(struct task_struct *tsk)
 	unsigned long stime, stime_scaled, steal_time;
 	struct cpu_accounting_data *acct = get_accounting(tsk);
 
-	stime = vtime_delta(tsk, &stime_scaled, &steal_time);
+	stime = vtime_delta(acct, &stime_scaled, &steal_time);
 	acct->idle_time += stime + steal_time;
 }
 
+static void vtime_account_irq_field(struct cpu_accounting_data *acct,
+				    unsigned long *field)
+{
+	unsigned long stime, stime_scaled;
+
+	vtime_delta_kernel(acct, &stime, &stime_scaled);
+	*field += stime;
+#ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
+	acct->stime_scaled += stime_scaled;
+#endif
+}
+
+void vtime_account_softirq(struct task_struct *tsk)
+{
+	struct cpu_accounting_data *acct = get_accounting(tsk);
+	vtime_account_irq_field(acct, &acct->softirq_time);
+}
+
+void vtime_account_hardirq(struct task_struct *tsk)
+{
+	struct cpu_accounting_data *acct = get_accounting(tsk);
+	vtime_account_irq_field(acct, &acct->hardirq_time);
+}
+
 static void vtime_flush_scaled(struct task_struct *tsk,
 			       struct cpu_accounting_data *acct)
 {
@ arch/powerpc/kernel/traps.c:173 @ extern void panic_flush_kmsg_start(void)
 
 extern void panic_flush_kmsg_end(void)
 {
-	printk_safe_flush_on_panic();
 	kmsg_dump(KMSG_DUMP_PANIC);
 	bust_spinlocks(0);
 	debug_locks_off();
@ arch/powerpc/kernel/traps.c:262 @ static char *get_mmu_str(void)
 
 static int __die(const char *str, struct pt_regs *regs, long err)
 {
+	const char *pr = "";
+
 	printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter);
 
+	if (IS_ENABLED(CONFIG_PREEMPTION))
+		pr = IS_ENABLED(CONFIG_PREEMPT_RT) ? " PREEMPT_RT" : " PREEMPT";
+
 	printk("%s PAGE_SIZE=%luK%s%s%s%s%s%s %s\n",
 	       IS_ENABLED(CONFIG_CPU_LITTLE_ENDIAN) ? "LE" : "BE",
 	       PAGE_SIZE / 1024, get_mmu_str(),
-	       IS_ENABLED(CONFIG_PREEMPT) ? " PREEMPT" : "",
+	       pr,
 	       IS_ENABLED(CONFIG_SMP) ? " SMP" : "",
 	       IS_ENABLED(CONFIG_SMP) ? (" NR_CPUS=" __stringify(NR_CPUS)) : "",
 	       debug_pagealloc_enabled() ? " DEBUG_PAGEALLOC" : "",
@ arch/powerpc/kernel/watchdog.c:184 @ static void watchdog_smp_panic(int cpu, u64 tb)
 
 	wd_smp_unlock(&flags);
 
-	printk_safe_flush();
-	/*
-	 * printk_safe_flush() seems to require another print
-	 * before anything actually goes out to console.
-	 */
 	if (sysctl_hardlockup_all_cpu_backtrace)
 		trigger_allbutself_cpu_backtrace();
 
@ arch/powerpc/kexec/crash.c:314 @ void default_machine_crash_shutdown(struct pt_regs *regs)
 	unsigned int i;
 	int (*old_handler)(struct pt_regs *regs);
 
-	/* Avoid hardlocking with irresponsive CPU holding logbuf_lock */
-	printk_nmi_enter();
-
 	/*
 	 * This function is only called after the system
 	 * has panicked or is otherwise in a critical state.
@ arch/powerpc/kvm/Kconfig:181 @ config KVM_E500MC
 config KVM_MPIC
 	bool "KVM in-kernel MPIC emulation"
 	depends on KVM && E500
+	depends on !PREEMPT_RT
 	select HAVE_KVM_IRQCHIP
 	select HAVE_KVM_IRQFD
 	select HAVE_KVM_IRQ_ROUTING
@ arch/powerpc/mm/Makefile:19 @ obj-$(CONFIG_NEED_MULTIPLE_NODES) += numa.o
 obj-$(CONFIG_PPC_MM_SLICES)	+= slice.o
 obj-$(CONFIG_HUGETLB_PAGE)	+= hugetlbpage.o
 obj-$(CONFIG_NOT_COHERENT_CACHE) += dma-noncoherent.o
-obj-$(CONFIG_HIGHMEM)		+= highmem.o
 obj-$(CONFIG_PPC_COPRO_BASE)	+= copro_fault.o
 obj-$(CONFIG_PPC_PTDUMP)	+= ptdump/
 obj-$(CONFIG_KASAN)		+= kasan/
@ arch/powerpc/mm/highmem.c:1 @
-// SPDX-License-Identifier: GPL-2.0
-/*
- * highmem.c: virtual kernel memory mappings for high memory
- *
- * PowerPC version, stolen from the i386 version.
- *
- * Used in CONFIG_HIGHMEM systems for memory pages which
- * are not addressable by direct kernel virtual addresses.
- *
- * Copyright (C) 1999 Gerhard Wichert, Siemens AG
- *		      Gerhard.Wichert@pdb.siemens.de
- *
- *
- * Redesigned the x86 32-bit VM architecture to deal with
- * up to 16 Terrabyte physical memory. With current x86 CPUs
- * we now support up to 64 Gigabytes physical RAM.
- *
- * Copyright (C) 1999 Ingo Molnar <mingo@redhat.com>
- *
- * Reworked for PowerPC by various contributors. Moved from
- * highmem.h by Benjamin Herrenschmidt (c) 2009 IBM Corp.
- */
-
-#include <linux/highmem.h>
-#include <linux/module.h>
-
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
-	unsigned long vaddr;
-	int idx, type;
-
-	type = kmap_atomic_idx_push();
-	idx = type + KM_TYPE_NR*smp_processor_id();
-	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-	WARN_ON(IS_ENABLED(CONFIG_DEBUG_HIGHMEM) && !pte_none(*(kmap_pte - idx)));
-	__set_pte_at(&init_mm, vaddr, kmap_pte-idx, mk_pte(page, prot), 1);
-	local_flush_tlb_page(NULL, vaddr);
-
-	return (void*) vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kvaddr)
-{
-	unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-
-	if (vaddr < __fix_to_virt(FIX_KMAP_END))
-		return;
-
-	if (IS_ENABLED(CONFIG_DEBUG_HIGHMEM)) {
-		int type = kmap_atomic_idx();
-		unsigned int idx;
-
-		idx = type + KM_TYPE_NR * smp_processor_id();
-		WARN_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
-
-		/*
-		 * force other mappings to Oops if they'll try to access
-		 * this pte without first remap it
-		 */
-		pte_clear(&init_mm, vaddr, kmap_pte-idx);
-		local_flush_tlb_page(NULL, vaddr);
-	}
-
-	kmap_atomic_idx_pop();
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
@ arch/powerpc/mm/mem.c:65 @
 unsigned long long memory_limit;
 bool init_mem_is_free;
 
-#ifdef CONFIG_HIGHMEM
-pte_t *kmap_pte;
-EXPORT_SYMBOL(kmap_pte);
-#endif
-
 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
 			      unsigned long size, pgprot_t vma_prot)
 {
@ arch/powerpc/mm/mem.c:234 @ void __init paging_init(void)
 
 	map_kernel_page(PKMAP_BASE, 0, __pgprot(0));	/* XXX gross */
 	pkmap_page_table = virt_to_kpte(PKMAP_BASE);
-
-	kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
 #endif /* CONFIG_HIGHMEM */
 
 	printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n",
@ arch/powerpc/platforms/powernv/opal-kmsg.c:23 @
  * message, it just ensures that OPAL completely flushes the console buffer.
  */
 static void kmsg_dump_opal_console_flush(struct kmsg_dumper *dumper,
-				     enum kmsg_dump_reason reason)
+					 enum kmsg_dump_reason reason,
+					 struct kmsg_dumper_iter *iter)
 {
 	/*
 	 * Outside of a panic context the pollers will continue to run,
@ arch/powerpc/platforms/pseries/iommu.c:27 @
 #include <linux/of.h>
 #include <linux/iommu.h>
 #include <linux/rculist.h>
+#include <linux/local_lock.h>
 #include <asm/io.h>
 #include <asm/prom.h>
 #include <asm/rtas.h>
@ arch/powerpc/platforms/pseries/iommu.c:194 @ static int tce_build_pSeriesLP(unsigned long liobn, long tcenum, long tceshift,
 	return ret;
 }
 
-static DEFINE_PER_CPU(__be64 *, tce_page);
+struct tce_page {
+	__be64 * page;
+	local_lock_t lock;
+};
+static DEFINE_PER_CPU(struct tce_page, tce_page) = {
+	.lock = INIT_LOCAL_LOCK(lock),
+};
 
 static int tce_buildmulti_pSeriesLP(struct iommu_table *tbl, long tcenum,
 				     long npages, unsigned long uaddr,
@ arch/powerpc/platforms/pseries/iommu.c:222 @ static int tce_buildmulti_pSeriesLP(struct iommu_table *tbl, long tcenum,
 		                           direction, attrs);
 	}
 
-	local_irq_save(flags);	/* to protect tcep and the page behind it */
+	/* to protect tcep and the page behind it */
+	local_lock_irqsave(&tce_page.lock, flags);
 
-	tcep = __this_cpu_read(tce_page);
+	tcep = __this_cpu_read(tce_page.page);
 
 	/* This is safe to do since interrupts are off when we're called
 	 * from iommu_alloc{,_sg}()
@ arch/powerpc/platforms/pseries/iommu.c:234 @ static int tce_buildmulti_pSeriesLP(struct iommu_table *tbl, long tcenum,
 		tcep = (__be64 *)__get_free_page(GFP_ATOMIC);
 		/* If allocation fails, fall back to the loop implementation */
 		if (!tcep) {
-			local_irq_restore(flags);
+			local_unlock_irqrestore(&tce_page.lock, flags);
 			return tce_build_pSeriesLP(tbl->it_index, tcenum,
 					tbl->it_page_shift,
 					npages, uaddr, direction, attrs);
 		}
-		__this_cpu_write(tce_page, tcep);
+		__this_cpu_write(tce_page.page, tcep);
 	}
 
 	rpn = __pa(uaddr) >> TCE_SHIFT;
@ arch/powerpc/platforms/pseries/iommu.c:269 @ static int tce_buildmulti_pSeriesLP(struct iommu_table *tbl, long tcenum,
 		tcenum += limit;
 	} while (npages > 0 && !rc);
 
-	local_irq_restore(flags);
+	local_unlock_irqrestore(&tce_page.lock, flags);
 
 	if (unlikely(rc == H_NOT_ENOUGH_RESOURCES)) {
 		ret = (int)rc;
@ arch/powerpc/platforms/pseries/iommu.c:440 @ static int tce_setrange_multi_pSeriesLP(unsigned long start_pfn,
 				DMA_BIDIRECTIONAL, 0);
 	}
 
-	local_irq_disable();	/* to protect tcep and the page behind it */
-	tcep = __this_cpu_read(tce_page);
+	/* to protect tcep and the page behind it */
+	local_lock_irq(&tce_page.lock);
+	tcep = __this_cpu_read(tce_page.page);
 
 	if (!tcep) {
 		tcep = (__be64 *)__get_free_page(GFP_ATOMIC);
 		if (!tcep) {
-			local_irq_enable();
+			local_unlock_irq(&tce_page.lock);
 			return -ENOMEM;
 		}
-		__this_cpu_write(tce_page, tcep);
+		__this_cpu_write(tce_page.page, tcep);
 	}
 
 	proto_tce = TCE_PCI_READ | TCE_PCI_WRITE;
@ arch/powerpc/platforms/pseries/iommu.c:493 @ static int tce_setrange_multi_pSeriesLP(unsigned long start_pfn,
 
 	/* error cleanup: caller will clear whole range */
 
-	local_irq_enable();
+	local_unlock_irq(&tce_page.lock);
 	return rc;
 }
 
@ arch/powerpc/xmon/xmon.c:3008 @ print_address(unsigned long addr)
 static void
 dump_log_buf(void)
 {
-	struct kmsg_dumper dumper = { .active = 1 };
+	struct kmsg_dumper_iter iter = { .active = 1 };
 	unsigned char buf[128];
 	size_t len;
 
@ arch/powerpc/xmon/xmon.c:3020 @ dump_log_buf(void)
 	catch_memory_errors = 1;
 	sync();
 
-	kmsg_dump_rewind_nolock(&dumper);
+	kmsg_dump_rewind(&iter);
 	xmon_start_pagination();
-	while (kmsg_dump_get_line_nolock(&dumper, false, buf, sizeof(buf), &len)) {
+	while (kmsg_dump_get_line(&iter, false, buf, sizeof(buf), &len)) {
 		buf[len] = '\0';
 		printf("%s", buf);
 	}
@ arch/s390/Kconfig:186 @ config S390
 	select HAVE_RSEQ
 	select HAVE_SYSCALL_TRACEPOINTS
 	select HAVE_VIRT_CPU_ACCOUNTING
+	select HAVE_VIRT_CPU_ACCOUNTING_IDLE
 	select IOMMU_HELPER		if PCI
 	select IOMMU_SUPPORT		if PCI
 	select MODULES_USE_ELF_RELA
@ arch/s390/include/asm/spinlock_types.h:5 @
 #ifndef __ASM_SPINLOCK_TYPES_H
 #define __ASM_SPINLOCK_TYPES_H
 
-#ifndef __LINUX_SPINLOCK_TYPES_H
-# error "please don't include this file directly"
-#endif
-
 typedef struct {
 	int lock;
 } __attribute__ ((aligned (4))) arch_spinlock_t;
@ arch/s390/include/asm/vtime.h:5 @
 #ifndef _S390_VTIME_H
 #define _S390_VTIME_H
 
-#define __ARCH_HAS_VTIME_ACCOUNT
 #define __ARCH_HAS_VTIME_TASK_SWITCH
 
 #endif /* _S390_VTIME_H */
@ arch/s390/kernel/vtime.c:226 @ void vtime_flush(struct task_struct *tsk)
 	S390_lowcore.avg_steal_timer = avg_steal;
 }
 
+static u64 vtime_delta(void)
+{
+	u64 timer = S390_lowcore.last_update_timer;
+
+	S390_lowcore.last_update_timer = get_vtimer();
+
+	return timer - S390_lowcore.last_update_timer;
+}
+
 /*
  * Update process times based on virtual cpu times stored by entry.S
  * to the lowcore fields user_timer, system_timer & steal_clock.
  */
-void vtime_account_irq_enter(struct task_struct *tsk)
+void vtime_account_kernel(struct task_struct *tsk)
 {
-	u64 timer;
-
-	timer = S390_lowcore.last_update_timer;
-	S390_lowcore.last_update_timer = get_vtimer();
-	timer -= S390_lowcore.last_update_timer;
+	u64 delta = vtime_delta();
 
-	if ((tsk->flags & PF_VCPU) && (irq_count() == 0))
-		S390_lowcore.guest_timer += timer;
-	else if (hardirq_count())
-		S390_lowcore.hardirq_timer += timer;
-	else if (in_serving_softirq())
-		S390_lowcore.softirq_timer += timer;
+	if (tsk->flags & PF_VCPU)
+		S390_lowcore.guest_timer += delta;
 	else
-		S390_lowcore.system_timer += timer;
+		S390_lowcore.system_timer += delta;
 
-	virt_timer_forward(timer);
+	virt_timer_forward(delta);
 }
-EXPORT_SYMBOL_GPL(vtime_account_irq_enter);
-
-void vtime_account_kernel(struct task_struct *tsk)
-__attribute__((alias("vtime_account_irq_enter")));
 EXPORT_SYMBOL_GPL(vtime_account_kernel);
 
+void vtime_account_softirq(struct task_struct *tsk)
+{
+	u64 delta = vtime_delta();
+
+	S390_lowcore.softirq_timer += delta;
+
+	virt_timer_forward(delta);
+}
+
+void vtime_account_hardirq(struct task_struct *tsk)
+{
+	u64 delta = vtime_delta();
+
+	S390_lowcore.hardirq_timer += delta;
+
+	virt_timer_forward(delta);
+}
+
 /*
  * Sorted add to a list. List is linear searched until first bigger
  * element is found.
@ arch/sh/include/asm/fixmap.h:16 @
 #include <linux/kernel.h>
 #include <linux/threads.h>
 #include <asm/page.h>
-#ifdef CONFIG_HIGHMEM
-#include <asm/kmap_types.h>
-#endif
 
 /*
  * Here we define all the compile-time 'special' virtual
@ arch/sh/include/asm/fixmap.h:53 @ enum fixed_addresses {
 	FIX_CMAP_BEGIN,
 	FIX_CMAP_END = FIX_CMAP_BEGIN + (FIX_N_COLOURS * NR_CPUS) - 1,
 
-#ifdef CONFIG_HIGHMEM
-	FIX_KMAP_BEGIN,	/* reserved pte's for temporary kernel mappings */
-	FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * NR_CPUS) - 1,
-#endif
-
 #ifdef CONFIG_IOREMAP_FIXED
 	/*
 	 * FIX_IOREMAP entries are useful for mapping physical address
@ arch/sh/include/asm/hardirq.h:5 @
 #ifndef __ASM_SH_HARDIRQ_H
 #define __ASM_SH_HARDIRQ_H
 
-#include <linux/threads.h>
-#include <linux/irq.h>
-
-typedef struct {
-	unsigned int __softirq_pending;
-	unsigned int __nmi_count;		/* arch dependent */
-} ____cacheline_aligned irq_cpustat_t;
-
-#include <linux/irq_cpustat.h>	/* Standard mappings for irq_cpustat_t above */
-
 extern void ack_bad_irq(unsigned int irq);
+#define ack_bad_irq ack_bad_irq
+#define ARCH_WANTS_NMI_IRQSTAT
+
+#include <asm-generic/hardirq.h>
 
 #endif /* __ASM_SH_HARDIRQ_H */
@ arch/sh/include/asm/kmap_types.h:1 @
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef __SH_KMAP_TYPES_H
-#define __SH_KMAP_TYPES_H
-
-/* Dummy header just to define km_type. */
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-#define  __WITH_KM_FENCE
-#endif
-
-#include <asm-generic/kmap_types.h>
-
-#undef __WITH_KM_FENCE
-
-#endif
@ arch/sh/include/asm/spinlock_types.h:5 @
 #ifndef __ASM_SH_SPINLOCK_TYPES_H
 #define __ASM_SH_SPINLOCK_TYPES_H
 
-#ifndef __LINUX_SPINLOCK_TYPES_H
-# error "please don't include this file directly"
-#endif
-
 typedef struct {
 	volatile unsigned int lock;
 } arch_spinlock_t;
@ arch/sh/kernel/irq.c:47 @ int arch_show_interrupts(struct seq_file *p, int prec)
 
 	seq_printf(p, "%*s: ", prec, "NMI");
 	for_each_online_cpu(j)
-		seq_printf(p, "%10u ", nmi_count(j));
+		seq_printf(p, "%10u ", per_cpu(irq_stat.__nmi_count, j));
 	seq_printf(p, "  Non-maskable interrupts\n");
 
 	seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
@ arch/sh/kernel/irq.c:151 @ void irq_ctx_exit(int cpu)
 	hardirq_ctx[cpu] = NULL;
 }
 
+#ifndef CONFIG_PREEMPT_RT
 void do_softirq_own_stack(void)
 {
 	struct thread_info *curctx;
@ arch/sh/kernel/irq.c:179 @ void do_softirq_own_stack(void)
 		  "r5", "r6", "r7", "r8", "r9", "r15", "t", "pr"
 	);
 }
+#endif
 #else
 static inline void handle_one_irq(unsigned int irq)
 {
@ arch/sh/kernel/traps.c:189 @ BUILD_TRAP_HANDLER(nmi)
 	arch_ftrace_nmi_enter();
 
 	nmi_enter();
-	nmi_count(cpu)++;
+	this_cpu_inc(irq_stat.__nmi_count);
 
 	switch (notify_die(DIE_NMI, "NMI", regs, 0, vec & 0xff, SIGINT)) {
 	case NOTIFY_OK:
@ arch/sh/mm/init.c:365 @ void __init mem_init(void)
 	mem_init_print_info(NULL);
 	pr_info("virtual kernel memory layout:\n"
 		"    fixmap  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
-#ifdef CONFIG_HIGHMEM
-		"    pkmap   : 0x%08lx - 0x%08lx   (%4ld kB)\n"
-#endif
 		"    vmalloc : 0x%08lx - 0x%08lx   (%4ld MB)\n"
 		"    lowmem  : 0x%08lx - 0x%08lx   (%4ld MB) (cached)\n"
 #ifdef CONFIG_UNCACHED_MAPPING
@ arch/sh/mm/init.c:376 @ void __init mem_init(void)
 		FIXADDR_START, FIXADDR_TOP,
 		(FIXADDR_TOP - FIXADDR_START) >> 10,
 
-#ifdef CONFIG_HIGHMEM
-		PKMAP_BASE, PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
-		(LAST_PKMAP*PAGE_SIZE) >> 10,
-#endif
-
 		(unsigned long)VMALLOC_START, VMALLOC_END,
 		(VMALLOC_END - VMALLOC_START) >> 20,
 
@ arch/sparc/Kconfig:142 @ config MMU
 config HIGHMEM
 	bool
 	default y if SPARC32
+	select KMAP_LOCAL
 
 config ZONE_DMA
 	bool
@ arch/sparc/include/asm/highmem.h:27 @
 #include <linux/interrupt.h>
 #include <linux/pgtable.h>
 #include <asm/vaddrs.h>
-#include <asm/kmap_types.h>
 #include <asm/pgtsrmmu.h>
 
 /* declarations for highmem.c */
@ arch/sparc/include/asm/highmem.h:35 @ extern unsigned long highstart_pfn, highend_pfn;
 #define kmap_prot __pgprot(SRMMU_ET_PTE | SRMMU_PRIV | SRMMU_CACHE)
 extern pte_t *pkmap_page_table;
 
-void kmap_init(void) __init;
-
 /*
  * Right now we initialize only a single pte table. It can be extended
  * easily, subsequent pte tables have to be allocated in one physical
@ arch/sparc/include/asm/highmem.h:53 @ void kmap_init(void) __init;
 
 #define flush_cache_kmaps()	flush_cache_all()
 
+/* FIXME: Use __flush_tlb_one(vaddr) instead of flush_cache_all() -- Anton */
+#define arch_kmap_local_post_map(vaddr, pteval)	flush_cache_all()
+#define arch_kmap_local_post_unmap(vaddr)	flush_cache_all()
+
+
 #endif /* __KERNEL__ */
 
 #endif /* _ASM_HIGHMEM_H */
@ arch/sparc/include/asm/kmap_types.h:1 @
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_KMAP_TYPES_H
-#define _ASM_KMAP_TYPES_H
-
-/* Dummy header just to define km_type.  None of this
- * is actually used on sparc.  -DaveM
- */
-
-#include <asm-generic/kmap_types.h>
-
-#endif
@ arch/sparc/include/asm/vaddrs.h:35 @
 #define SRMMU_NOCACHE_ALCRATIO	64	/* 256 pages per 64MB of system RAM */
 
 #ifndef __ASSEMBLY__
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
 
 enum fixed_addresses {
 	FIX_HOLE,
 #ifdef CONFIG_HIGHMEM
 	FIX_KMAP_BEGIN,
-	FIX_KMAP_END = (KM_TYPE_NR * NR_CPUS),
+	FIX_KMAP_END = (KM_MAX_IDX * NR_CPUS),
 #endif
 	__end_of_fixed_addresses
 };
@ arch/sparc/kernel/irq_64.c:857 @ void __irq_entry handler_irq(int pil, struct pt_regs *regs)
 	set_irq_regs(old_regs);
 }
 
+#ifndef CONFIG_PREEMPT_RT
 void do_softirq_own_stack(void)
 {
 	void *orig_sp, *sp = softirq_stack[smp_processor_id()];
@ arch/sparc/kernel/irq_64.c:872 @ void do_softirq_own_stack(void)
 	__asm__ __volatile__("mov %0, %%sp"
 			     : : "r" (orig_sp));
 }
+#endif
 
 #ifdef CONFIG_HOTPLUG_CPU
 void fixup_irqs(void)
@ arch/sparc/mm/Makefile:18 @ obj-$(CONFIG_SPARC32)   += leon_mm.o
 
 # Only used by sparc64
 obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
-
-# Only used by sparc32
-obj-$(CONFIG_HIGHMEM)   += highmem.o
@ arch/sparc/mm/highmem.c:1 @
-// SPDX-License-Identifier: GPL-2.0
-/*
- *  highmem.c: virtual kernel memory mappings for high memory
- *
- *  Provides kernel-static versions of atomic kmap functions originally
- *  found as inlines in include/asm-sparc/highmem.h.  These became
- *  needed as kmap_atomic() and kunmap_atomic() started getting
- *  called from within modules.
- *  -- Tomas Szepe <szepe@pinerecords.com>, September 2002
- *
- *  But kmap_atomic() and kunmap_atomic() cannot be inlined in
- *  modules because they are loaded with btfixup-ped functions.
- */
-
-/*
- * The use of kmap_atomic/kunmap_atomic is discouraged - kmap/kunmap
- * gives a more generic (and caching) interface. But kmap_atomic can
- * be used in IRQ contexts, so in some (very limited) cases we need it.
- *
- * XXX This is an old text. Actually, it's good to use atomic kmaps,
- * provided you remember that they are atomic and not try to sleep
- * with a kmap taken, much like a spinlock. Non-atomic kmaps are
- * shared by CPUs, and so precious, and establishing them requires IPI.
- * Atomic kmaps are lightweight and we may have NCPUS more of them.
- */
-#include <linux/highmem.h>
-#include <linux/export.h>
-#include <linux/mm.h>
-
-#include <asm/cacheflush.h>
-#include <asm/tlbflush.h>
-#include <asm/vaddrs.h>
-
-static pte_t *kmap_pte;
-
-void __init kmap_init(void)
-{
-	unsigned long address = __fix_to_virt(FIX_KMAP_BEGIN);
-
-        /* cache the first kmap pte */
-        kmap_pte = virt_to_kpte(address);
-}
-
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
-	unsigned long vaddr;
-	long idx, type;
-
-	type = kmap_atomic_idx_push();
-	idx = type + KM_TYPE_NR*smp_processor_id();
-	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-
-/* XXX Fix - Anton */
-#if 0
-	__flush_cache_one(vaddr);
-#else
-	flush_cache_all();
-#endif
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-	BUG_ON(!pte_none(*(kmap_pte-idx)));
-#endif
-	set_pte(kmap_pte-idx, mk_pte(page, prot));
-/* XXX Fix - Anton */
-#if 0
-	__flush_tlb_one(vaddr);
-#else
-	flush_tlb_all();
-#endif
-
-	return (void*) vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kvaddr)
-{
-	unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-	int type;
-
-	if (vaddr < FIXADDR_START)
-		return;
-
-	type = kmap_atomic_idx();
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-	{
-		unsigned long idx;
-
-		idx = type + KM_TYPE_NR * smp_processor_id();
-		BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN+idx));
-
-		/* XXX Fix - Anton */
-#if 0
-		__flush_cache_one(vaddr);
-#else
-		flush_cache_all();
-#endif
-
-		/*
-		 * force other mappings to Oops if they'll try to access
-		 * this pte without first remap it
-		 */
-		pte_clear(&init_mm, vaddr, kmap_pte-idx);
-		/* XXX Fix - Anton */
-#if 0
-		__flush_tlb_one(vaddr);
-#else
-		flush_tlb_all();
-#endif
-	}
-#endif
-
-	kmap_atomic_idx_pop();
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
@ arch/sparc/mm/srmmu.c:974 @ void __init srmmu_paging_init(void)
 
 	sparc_context_init(num_contexts);
 
-	kmap_init();
-
 	{
 		unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0 };
 
@ arch/um/include/asm/fixmap.h:6 @
 #define __UM_FIXMAP_H
 
 #include <asm/processor.h>
-#include <asm/kmap_types.h>
 #include <asm/archparam.h>
 #include <asm/page.h>
 #include <linux/threads.h>
@ arch/um/include/asm/hardirq.h:5 @
 #ifndef __ASM_UM_HARDIRQ_H
 #define __ASM_UM_HARDIRQ_H
 
-#include <linux/cache.h>
-#include <linux/threads.h>
-
-typedef struct {
-	unsigned int __softirq_pending;
-} ____cacheline_aligned irq_cpustat_t;
-
-#include <linux/irq_cpustat.h>	/* Standard mappings for irq_cpustat_t above */
-#include <linux/irq.h>
-
-#ifndef ack_bad_irq
-static inline void ack_bad_irq(unsigned int irq)
-{
-	printk(KERN_CRIT "unexpected IRQ trap at vector %02x\n", irq);
-}
-#endif
+#include <asm-generic/hardirq.h>
 
 #define __ARCH_IRQ_EXIT_IRQS_DISABLED 1
 
@ arch/um/include/asm/kmap_types.h:1 @
-/* SPDX-License-Identifier: GPL-2.0 */
-/* 
- * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
- */
-
-#ifndef __UM_KMAP_TYPES_H
-#define __UM_KMAP_TYPES_H
-
-/* No more #include "asm/arch/kmap_types.h" ! */
-
-#define KM_TYPE_NR 14
-
-#endif
@ arch/um/kernel/kmsg_dump.c:4 @
 // SPDX-License-Identifier: GPL-2.0
 #include <linux/kmsg_dump.h>
+#include <linux/spinlock.h>
 #include <linux/console.h>
 #include <shared/init.h>
 #include <shared/kern.h>
 #include <os.h>
 
 static void kmsg_dumper_stdout(struct kmsg_dumper *dumper,
-				enum kmsg_dump_reason reason)
+				enum kmsg_dump_reason reason,
+				struct kmsg_dumper_iter *iter)
 {
+	static DEFINE_SPINLOCK(lock);
 	static char line[1024];
 	struct console *con;
+	unsigned long flags;
 	size_t len = 0;
 
 	/* only dump kmsg when no console is available */
@ arch/um/kernel/kmsg_dump.c:31 @ static void kmsg_dumper_stdout(struct kmsg_dumper *dumper,
 	if (con)
 		return;
 
+	if (!spin_trylock_irqsave(&lock, flags))
+		return;
+
 	printf("kmsg_dump:\n");
-	while (kmsg_dump_get_line(dumper, true, line, sizeof(line), &len)) {
+	while (kmsg_dump_get_line(iter, true, line, sizeof(line), &len)) {
 		line[len] = '\0';
 		printf("%s", line);
 	}
+
+	spin_unlock_irqrestore(&lock, flags);
 }
 
 static struct kmsg_dumper kmsg_dumper = {
@ arch/x86/Kconfig:18 @ config X86_32
 	select CLKSRC_I8253
 	select CLONE_BACKWARDS
 	select HAVE_DEBUG_STACKOVERFLOW
+	select KMAP_LOCAL
 	select MODULES_USE_ELF_REL
 	select OLD_SIGACTION
 	select GENERIC_VDSO_32
@ arch/x86/Kconfig:97 @ config X86
 	select ARCH_SUPPORTS_ACPI
 	select ARCH_SUPPORTS_ATOMIC_RMW
 	select ARCH_SUPPORTS_NUMA_BALANCING	if X86_64
+	select ARCH_SUPPORTS_RT
 	select ARCH_USE_BUILTIN_BSWAP
 	select ARCH_USE_QUEUED_RWLOCKS
 	select ARCH_USE_QUEUED_SPINLOCKS
@ arch/x86/Kconfig:215 @ config X86
 	select HAVE_PCI
 	select HAVE_PERF_REGS
 	select HAVE_PERF_USER_STACK_DUMP
+	select HAVE_PREEMPT_LAZY
 	select MMU_GATHER_RCU_TABLE_FREE		if PARAVIRT
 	select HAVE_POSIX_CPU_TIMERS_TASK_WORK
 	select HAVE_REGS_AND_STACK_ACCESS_API
@ arch/x86/crypto/aesni-intel_glue.c:382 @ static int ecb_encrypt(struct skcipher_request *req)
 
 	err = skcipher_walk_virt(&walk, req, true);
 
-	kernel_fpu_begin();
 	while ((nbytes = walk.nbytes)) {
+		kernel_fpu_begin();
 		aesni_ecb_enc(ctx, walk.dst.virt.addr, walk.src.virt.addr,
 			      nbytes & AES_BLOCK_MASK);
+		kernel_fpu_end();
 		nbytes &= AES_BLOCK_SIZE - 1;
 		err = skcipher_walk_done(&walk, nbytes);
 	}
-	kernel_fpu_end();
 
 	return err;
 }
@ arch/x86/crypto/aesni-intel_glue.c:404 @ static int ecb_decrypt(struct skcipher_request *req)
 
 	err = skcipher_walk_virt(&walk, req, true);
 
-	kernel_fpu_begin();
 	while ((nbytes = walk.nbytes)) {
+		kernel_fpu_begin();
 		aesni_ecb_dec(ctx, walk.dst.virt.addr, walk.src.virt.addr,
 			      nbytes & AES_BLOCK_MASK);
+		kernel_fpu_end();
 		nbytes &= AES_BLOCK_SIZE - 1;
 		err = skcipher_walk_done(&walk, nbytes);
 	}
-	kernel_fpu_end();
 
 	return err;
 }
@ arch/x86/crypto/aesni-intel_glue.c:426 @ static int cbc_encrypt(struct skcipher_request *req)
 
 	err = skcipher_walk_virt(&walk, req, true);
 
-	kernel_fpu_begin();
 	while ((nbytes = walk.nbytes)) {
+		kernel_fpu_begin();
 		aesni_cbc_enc(ctx, walk.dst.virt.addr, walk.src.virt.addr,
 			      nbytes & AES_BLOCK_MASK, walk.iv);
+		kernel_fpu_end();
 		nbytes &= AES_BLOCK_SIZE - 1;
 		err = skcipher_walk_done(&walk, nbytes);
 	}
-	kernel_fpu_end();
 
 	return err;
 }
@ arch/x86/crypto/aesni-intel_glue.c:448 @ static int cbc_decrypt(struct skcipher_request *req)
 
 	err = skcipher_walk_virt(&walk, req, true);
 
-	kernel_fpu_begin();
 	while ((nbytes = walk.nbytes)) {
+		kernel_fpu_begin();
 		aesni_cbc_dec(ctx, walk.dst.virt.addr, walk.src.virt.addr,
 			      nbytes & AES_BLOCK_MASK, walk.iv);
+		kernel_fpu_end();
 		nbytes &= AES_BLOCK_SIZE - 1;
 		err = skcipher_walk_done(&walk, nbytes);
 	}
-	kernel_fpu_end();
 
 	return err;
 }
@ arch/x86/crypto/aesni-intel_glue.c:503 @ static int ctr_crypt(struct skcipher_request *req)
 
 	err = skcipher_walk_virt(&walk, req, true);
 
-	kernel_fpu_begin();
 	while ((nbytes = walk.nbytes) >= AES_BLOCK_SIZE) {
+		kernel_fpu_begin();
 		aesni_ctr_enc_tfm(ctx, walk.dst.virt.addr, walk.src.virt.addr,
 			              nbytes & AES_BLOCK_MASK, walk.iv);
+		kernel_fpu_end();
 		nbytes &= AES_BLOCK_SIZE - 1;
 		err = skcipher_walk_done(&walk, nbytes);
 	}
 	if (walk.nbytes) {
+		kernel_fpu_begin();
 		ctr_crypt_final(ctx, &walk);
+		kernel_fpu_end();
 		err = skcipher_walk_done(&walk, 0);
 	}
-	kernel_fpu_end();
 
 	return err;
 }
@ arch/x86/crypto/cast5_avx_glue.c:49 @ static inline void cast5_fpu_end(bool fpu_enabled)
 
 static int ecb_crypt(struct skcipher_request *req, bool enc)
 {
-	bool fpu_enabled = false;
+	bool fpu_enabled;
 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 	struct cast5_ctx *ctx = crypto_skcipher_ctx(tfm);
 	struct skcipher_walk walk;
@ arch/x86/crypto/cast5_avx_glue.c:64 @ static int ecb_crypt(struct skcipher_request *req, bool enc)
 		u8 *wsrc = walk.src.virt.addr;
 		u8 *wdst = walk.dst.virt.addr;
 
-		fpu_enabled = cast5_fpu_begin(fpu_enabled, &walk, nbytes);
+		fpu_enabled = cast5_fpu_begin(false, &walk, nbytes);
 
 		/* Process multi-block batch */
 		if (nbytes >= bsize * CAST5_PARALLEL_BLOCKS) {
@ arch/x86/crypto/cast5_avx_glue.c:93 @ static int ecb_crypt(struct skcipher_request *req, bool enc)
 		} while (nbytes >= bsize);
 
 done:
+		cast5_fpu_end(fpu_enabled);
 		err = skcipher_walk_done(&walk, nbytes);
 	}
-
-	cast5_fpu_end(fpu_enabled);
 	return err;
 }
 
@ arch/x86/crypto/cast5_avx_glue.c:199 @ static int cbc_decrypt(struct skcipher_request *req)
 {
 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 	struct cast5_ctx *ctx = crypto_skcipher_ctx(tfm);
-	bool fpu_enabled = false;
+	bool fpu_enabled;
 	struct skcipher_walk walk;
 	unsigned int nbytes;
 	int err;
@ arch/x86/crypto/cast5_avx_glue.c:207 @ static int cbc_decrypt(struct skcipher_request *req)
 	err = skcipher_walk_virt(&walk, req, false);
 
 	while ((nbytes = walk.nbytes)) {
-		fpu_enabled = cast5_fpu_begin(fpu_enabled, &walk, nbytes);
+		fpu_enabled = cast5_fpu_begin(false, &walk, nbytes);
 		nbytes = __cbc_decrypt(ctx, &walk);
+		cast5_fpu_end(fpu_enabled);
 		err = skcipher_walk_done(&walk, nbytes);
 	}
-
-	cast5_fpu_end(fpu_enabled);
 	return err;
 }
 
@ arch/x86/crypto/cast5_avx_glue.c:278 @ static int ctr_crypt(struct skcipher_request *req)
 {
 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 	struct cast5_ctx *ctx = crypto_skcipher_ctx(tfm);
-	bool fpu_enabled = false;
+	bool fpu_enabled;
 	struct skcipher_walk walk;
 	unsigned int nbytes;
 	int err;
@ arch/x86/crypto/cast5_avx_glue.c:286 @ static int ctr_crypt(struct skcipher_request *req)
 	err = skcipher_walk_virt(&walk, req, false);
 
 	while ((nbytes = walk.nbytes) >= CAST5_BLOCK_SIZE) {
-		fpu_enabled = cast5_fpu_begin(fpu_enabled, &walk, nbytes);
+		fpu_enabled = cast5_fpu_begin(false, &walk, nbytes);
 		nbytes = __ctr_crypt(&walk, ctx);
+		cast5_fpu_end(fpu_enabled);
 		err = skcipher_walk_done(&walk, nbytes);
 	}
 
-	cast5_fpu_end(fpu_enabled);
-
 	if (walk.nbytes) {
 		ctr_crypt_final(&walk, ctx);
 		err = skcipher_walk_done(&walk, 0);
@ arch/x86/crypto/glue_helper.c:27 @ int glue_ecb_req_128bit(const struct common_glue_ctx *gctx,
 	void *ctx = crypto_skcipher_ctx(crypto_skcipher_reqtfm(req));
 	const unsigned int bsize = 128 / 8;
 	struct skcipher_walk walk;
-	bool fpu_enabled = false;
+	bool fpu_enabled;
 	unsigned int nbytes;
 	int err;
 
@ arch/x86/crypto/glue_helper.c:40 @ int glue_ecb_req_128bit(const struct common_glue_ctx *gctx,
 		unsigned int i;
 
 		fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
-					     &walk, fpu_enabled, nbytes);
+					     &walk, false, nbytes);
 		for (i = 0; i < gctx->num_funcs; i++) {
 			func_bytes = bsize * gctx->funcs[i].num_blocks;
 
@ arch/x86/crypto/glue_helper.c:58 @ int glue_ecb_req_128bit(const struct common_glue_ctx *gctx,
 			if (nbytes < bsize)
 				break;
 		}
+		glue_fpu_end(fpu_enabled);
 		err = skcipher_walk_done(&walk, nbytes);
 	}
-
-	glue_fpu_end(fpu_enabled);
 	return err;
 }
 EXPORT_SYMBOL_GPL(glue_ecb_req_128bit);
@ arch/x86/crypto/glue_helper.c:103 @ int glue_cbc_decrypt_req_128bit(const struct common_glue_ctx *gctx,
 	void *ctx = crypto_skcipher_ctx(crypto_skcipher_reqtfm(req));
 	const unsigned int bsize = 128 / 8;
 	struct skcipher_walk walk;
-	bool fpu_enabled = false;
+	bool fpu_enabled;
 	unsigned int nbytes;
 	int err;
 
@ arch/x86/crypto/glue_helper.c:117 @ int glue_cbc_decrypt_req_128bit(const struct common_glue_ctx *gctx,
 		u128 last_iv;
 
 		fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
-					     &walk, fpu_enabled, nbytes);
+					     &walk, false, nbytes);
 		/* Start of the last block. */
 		src += nbytes / bsize - 1;
 		dst += nbytes / bsize - 1;
@ arch/x86/crypto/glue_helper.c:150 @ int glue_cbc_decrypt_req_128bit(const struct common_glue_ctx *gctx,
 done:
 		u128_xor(dst, dst, (u128 *)walk.iv);
 		*(u128 *)walk.iv = last_iv;
+		glue_fpu_end(fpu_enabled);
 		err = skcipher_walk_done(&walk, nbytes);
 	}
 
-	glue_fpu_end(fpu_enabled);
 	return err;
 }
 EXPORT_SYMBOL_GPL(glue_cbc_decrypt_req_128bit);
@ arch/x86/crypto/glue_helper.c:164 @ int glue_ctr_req_128bit(const struct common_glue_ctx *gctx,
 	void *ctx = crypto_skcipher_ctx(crypto_skcipher_reqtfm(req));
 	const unsigned int bsize = 128 / 8;
 	struct skcipher_walk walk;
-	bool fpu_enabled = false;
+	bool fpu_enabled;
 	unsigned int nbytes;
 	int err;
 
@ arch/x86/crypto/glue_helper.c:178 @ int glue_ctr_req_128bit(const struct common_glue_ctx *gctx,
 		le128 ctrblk;
 
 		fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
-					     &walk, fpu_enabled, nbytes);
+					     &walk, false, nbytes);
 
 		be128_to_le128(&ctrblk, (be128 *)walk.iv);
 
@ arch/x86/crypto/glue_helper.c:204 @ int glue_ctr_req_128bit(const struct common_glue_ctx *gctx,
 		}
 
 		le128_to_be128((be128 *)walk.iv, &ctrblk);
+		glue_fpu_end(fpu_enabled);
 		err = skcipher_walk_done(&walk, nbytes);
 	}
 
-	glue_fpu_end(fpu_enabled);
-
 	if (nbytes) {
 		le128 ctrblk;
 		u128 tmp;
@ arch/x86/crypto/glue_helper.c:307 @ int glue_xts_req_128bit(const struct common_glue_ctx *gctx,
 	tweak_fn(tweak_ctx, walk.iv, walk.iv);
 
 	while (nbytes) {
+		fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
+					     &walk, fpu_enabled,
+					     nbytes < bsize ? bsize : nbytes);
 		nbytes = __glue_xts_req_128bit(gctx, crypt_ctx, &walk);
 
+		glue_fpu_end(fpu_enabled);
+		fpu_enabled = false;
+
 		err = skcipher_walk_done(&walk, nbytes);
 		nbytes = walk.nbytes;
 	}
@ arch/x86/include/asm/fixmap.h:34 @
 #include <asm/pgtable_types.h>
 #ifdef CONFIG_X86_32
 #include <linux/threads.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
 #else
 #include <uapi/asm/vsyscall.h>
 #endif
@ arch/x86/include/asm/fixmap.h:97 @ enum fixed_addresses {
 #endif
 #ifdef CONFIG_X86_32
 	FIX_KMAP_BEGIN,	/* reserved pte's for temporary kernel mappings */
-	FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1,
+	FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1,
 #ifdef CONFIG_PCI_MMCONFIG
 	FIX_PCIE_MCFG,
 #endif
@ arch/x86/include/asm/fixmap.h:154 @ extern void reserve_top_address(unsigned long reserve);
 
 extern int fixmaps_set;
 
-extern pte_t *kmap_pte;
 extern pte_t *pkmap_page_table;
 
 void __native_set_fixmap(enum fixed_addresses idx, pte_t pte);
@ arch/x86/include/asm/fpu/api.h:31 @ extern void kernel_fpu_begin_mask(unsigned int kfpu_mask);
 extern void kernel_fpu_end(void);
 extern bool irq_fpu_usable(void);
 extern void fpregs_mark_activate(void);
+extern void kernel_fpu_resched(void);
 
 /* Code that is unaware of kernel_fpu_begin_mask() can use this */
 static inline void kernel_fpu_begin(void)
@ arch/x86/include/asm/fpu/api.h:44 @ static inline void kernel_fpu_begin(void)
  * A context switch will (and softirq might) save CPU's FPU registers to
  * fpu->state and set TIF_NEED_FPU_LOAD leaving CPU's FPU registers in
  * a random state.
+ *
+ * local_bh_disable() protects against both preemption and soft interrupts
+ * on !RT kernels.
+ *
+ * On RT kernels local_bh_disable() is not sufficient because it only
+ * serializes soft interrupt related sections via a local lock, but stays
+ * preemptible. Disabling preemption is the right choice here as bottom
+ * half processing is always in thread context on RT kernels so it
+ * implicitly prevents bottom half processing as well.
+ *
+ * Disabling preemption also serializes against kernel_fpu_begin().
  */
 static inline void fpregs_lock(void)
 {
-	preempt_disable();
-	local_bh_disable();
+	if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+		local_bh_disable();
+	else
+		preempt_disable();
 }
 
 static inline void fpregs_unlock(void)
 {
-	local_bh_enable();
-	preempt_enable();
+	if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+		local_bh_enable();
+	else
+		preempt_enable();
 }
 
 #ifdef CONFIG_X86_DEBUG_FPU
@ arch/x86/include/asm/highmem.h:26 @
 
 #include <linux/interrupt.h>
 #include <linux/threads.h>
-#include <asm/kmap_types.h>
 #include <asm/tlbflush.h>
 #include <asm/paravirt.h>
 #include <asm/fixmap.h>
@ arch/x86/include/asm/highmem.h:60 @ extern unsigned long highstart_pfn, highend_pfn;
 #define PKMAP_NR(virt)  ((virt-PKMAP_BASE) >> PAGE_SHIFT)
 #define PKMAP_ADDR(nr)  (PKMAP_BASE + ((nr) << PAGE_SHIFT))
 
-void *kmap_atomic_pfn(unsigned long pfn);
-void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot);
-
 #define flush_cache_kmaps()	do { } while (0)
 
+#define	arch_kmap_local_post_map(vaddr, pteval)		\
+	arch_flush_lazy_mmu_mode()
+
+#define	arch_kmap_local_post_unmap(vaddr)		\
+	do {						\
+		flush_tlb_one_kernel((vaddr));		\
+		arch_flush_lazy_mmu_mode();		\
+	} while (0)
+
 extern void add_highpages_with_active_regions(int nid, unsigned long start_pfn,
 					unsigned long end_pfn);
 
@ arch/x86/include/asm/iomap.h:12 @
 #include <linux/fs.h>
 #include <linux/mm.h>
 #include <linux/uaccess.h>
+#include <linux/highmem.h>
 #include <asm/cacheflush.h>
 #include <asm/tlbflush.h>
 
-void __iomem *
-iomap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot);
+void __iomem *__iomap_local_pfn_prot(unsigned long pfn, pgprot_t prot);
 
-void
-iounmap_atomic(void __iomem *kvaddr);
+int iomap_create_wc(resource_size_t base, unsigned long size, pgprot_t *prot);
 
-int
-iomap_create_wc(resource_size_t base, unsigned long size, pgprot_t *prot);
-
-void
-iomap_free(resource_size_t base, unsigned long size);
+void iomap_free(resource_size_t base, unsigned long size);
 
 #endif /* _ASM_X86_IOMAP_H */
@ arch/x86/include/asm/kmap_types.h:1 @
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_X86_KMAP_TYPES_H
-#define _ASM_X86_KMAP_TYPES_H
-
-#if defined(CONFIG_X86_32) && defined(CONFIG_DEBUG_HIGHMEM)
-#define  __WITH_KM_FENCE
-#endif
-
-#include <asm-generic/kmap_types.h>
-
-#undef __WITH_KM_FENCE
-
-#endif /* _ASM_X86_KMAP_TYPES_H */
@ arch/x86/include/asm/paravirt_types.h:44 @
 #ifndef __ASSEMBLY__
 
 #include <asm/desc_defs.h>
-#include <asm/kmap_types.h>
 #include <asm/pgtable_types.h>
 #include <asm/nospec-branch.h>
 
@ arch/x86/include/asm/preempt.h:92 @ static __always_inline void __preempt_count_sub(int val)
  * a decrement which hits zero means we have no preempt_count and should
  * reschedule.
  */
-static __always_inline bool __preempt_count_dec_and_test(void)
+static __always_inline bool ____preempt_count_dec_and_test(void)
 {
 	return GEN_UNARY_RMWcc("decl", __preempt_count, e, __percpu_arg([var]));
 }
 
+static __always_inline bool __preempt_count_dec_and_test(void)
+{
+	if (____preempt_count_dec_and_test())
+		return true;
+#ifdef CONFIG_PREEMPT_LAZY
+	if (preempt_count())
+		return false;
+	if (current_thread_info()->preempt_lazy_count)
+		return false;
+	return test_thread_flag(TIF_NEED_RESCHED_LAZY);
+#else
+	return false;
+#endif
+}
+
 /*
  * Returns true when we need to resched and can (barring IRQ state).
  */
 static __always_inline bool should_resched(int preempt_offset)
 {
+#ifdef CONFIG_PREEMPT_LAZY
+	u32 tmp;
+	tmp = raw_cpu_read_4(__preempt_count);
+	if (tmp == preempt_offset)
+		return true;
+
+	/* preempt count == 0 ? */
+	tmp &= ~PREEMPT_NEED_RESCHED;
+	if (tmp != preempt_offset)
+		return false;
+	/* XXX PREEMPT_LOCK_OFFSET */
+	if (current_thread_info()->preempt_lazy_count)
+		return false;
+	return test_thread_flag(TIF_NEED_RESCHED_LAZY);
+#else
 	return unlikely(raw_cpu_read_4(__preempt_count) == preempt_offset);
+#endif
 }
 
 #ifdef CONFIG_PREEMPTION
+#ifdef CONFIG_PREEMPT_RT
+  extern void preempt_schedule_lock(void);
+#endif
   extern asmlinkage void preempt_schedule_thunk(void);
 # define __preempt_schedule() \
 	asm volatile ("call preempt_schedule_thunk" : ASM_CALL_CONSTRAINT)
@ arch/x86/include/asm/signal.h:31 @ typedef struct {
 #define SA_IA32_ABI	0x02000000u
 #define SA_X32_ABI	0x01000000u
 
+/*
+ * Because some traps use the IST stack, we must keep preemption
+ * disabled while calling do_trap(), but do_trap() may call
+ * force_sig_info() which will grab the signal spin_locks for the
+ * task, which in PREEMPT_RT are mutexes.  By defining
+ * ARCH_RT_DELAYS_SIGNAL_SEND the force_sig_info() will set
+ * TIF_NOTIFY_RESUME and set up the signal to be sent on exit of the
+ * trap.
+ */
+#if defined(CONFIG_PREEMPT_RT)
+#define ARCH_RT_DELAYS_SIGNAL_SEND
+#endif
+
 #ifndef CONFIG_COMPAT
 typedef sigset_t compat_sigset_t;
 #endif
@ arch/x86/include/asm/stackprotector.h:68 @
  */
 static __always_inline void boot_init_stack_canary(void)
 {
-	u64 canary;
+	u64 canary = 0;
 	u64 tsc;
 
 #ifdef CONFIG_X86_64
@ arch/x86/include/asm/stackprotector.h:79 @ static __always_inline void boot_init_stack_canary(void)
 	 * of randomness. The TSC only matters for very early init,
 	 * there it already has some randomness on most systems. Later
 	 * on during the bootup the random pool has true entropy too.
+	 * For preempt-rt we need to weaken the randomness a bit, as
+	 * we can't call into the random generator from atomic context
+	 * due to locking constraints. We just leave canary
+	 * uninitialized and use the TSC based randomness on top of it.
 	 */
+#ifndef CONFIG_PREEMPT_RT
 	get_random_bytes(&canary, sizeof(canary));
+#endif
 	tsc = rdtsc();
 	canary += tsc + (tsc << 32UL);
 	canary &= CANARY_MASK;
@ arch/x86/include/asm/thread_info.h:59 @ struct task_struct;
 struct thread_info {
 	unsigned long		flags;		/* low level flags */
 	u32			status;		/* thread synchronous flags */
+	int			preempt_lazy_count;	/* 0 => lazy preemptable
+							  <0 => BUG */
 };
 
 #define INIT_THREAD_INFO(tsk)			\
 {						\
 	.flags		= 0,			\
+	.preempt_lazy_count = 0,		\
 }
 
 #else /* !__ASSEMBLY__ */
 
 #include <asm/asm-offsets.h>
 
+#define GET_THREAD_INFO(reg) \
+	_ASM_MOV PER_CPU_VAR(cpu_current_top_of_stack),reg ; \
+	_ASM_SUB $(THREAD_SIZE),reg ;
+
 #endif
 
 /*
@ arch/x86/include/asm/thread_info.h:103 @ struct thread_info {
 #define TIF_NOTSC		16	/* TSC is not accessible in userland */
 #define TIF_IA32		17	/* IA32 compatibility process */
 #define TIF_SLD			18	/* Restore split lock detection on context switch */
+#define TIF_NEED_RESCHED_LAZY	19	/* lazy rescheduling necessary */
 #define TIF_MEMDIE		20	/* is terminating due to OOM killer */
 #define TIF_POLLING_NRFLAG	21	/* idle is polling for TIF_NEED_RESCHED */
 #define TIF_IO_BITMAP		22	/* uses I/O bitmap */
@ arch/x86/include/asm/thread_info.h:133 @ struct thread_info {
 #define _TIF_NOTSC		(1 << TIF_NOTSC)
 #define _TIF_IA32		(1 << TIF_IA32)
 #define _TIF_SLD		(1 << TIF_SLD)
+#define _TIF_NEED_RESCHED_LAZY	(1 << TIF_NEED_RESCHED_LAZY)
 #define _TIF_POLLING_NRFLAG	(1 << TIF_POLLING_NRFLAG)
 #define _TIF_IO_BITMAP		(1 << TIF_IO_BITMAP)
 #define _TIF_FORCED_TF		(1 << TIF_FORCED_TF)
@ arch/x86/include/asm/thread_info.h:166 @ struct thread_info {
 
 #define _TIF_WORK_CTXSW_NEXT	(_TIF_WORK_CTXSW)
 
+#define _TIF_NEED_RESCHED_MASK	(_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY)
+
 #define STACK_WARN		(THREAD_SIZE/8)
 
 /*
@ arch/x86/kernel/cpu/mshyperv.c:83 @ EXPORT_SYMBOL_GPL(hv_remove_vmbus_irq);
 DEFINE_IDTENTRY_SYSVEC(sysvec_hyperv_stimer0)
 {
 	struct pt_regs *old_regs = set_irq_regs(regs);
+	u64 ip = regs ? instruction_pointer(regs) : 0;
 
 	inc_irq_stat(hyperv_stimer0_count);
 	if (hv_stimer0_handler)
 		hv_stimer0_handler();
-	add_interrupt_randomness(HYPERV_STIMER0_VECTOR, 0);
+	add_interrupt_randomness(HYPERV_STIMER0_VECTOR, 0, ip);
 	ack_APIC_irq();
 
 	set_irq_regs(old_regs);
@ arch/x86/kernel/crash_dump_32.c:16 @
 
 #include <linux/uaccess.h>
 
-static void *kdump_buf_page;
-
 static inline bool is_crashed_pfn_valid(unsigned long pfn)
 {
 #ifndef CONFIG_X86_PAE
@ arch/x86/kernel/crash_dump_32.c:42 @ static inline bool is_crashed_pfn_valid(unsigned long pfn)
  * @userbuf: if set, @buf is in user address space, use copy_to_user(),
  *	otherwise @buf is in kernel address space, use memcpy().
  *
- * Copy a page from "oldmem". For this page, there is no pte mapped
- * in the current kernel. We stitch up a pte, similar to kmap_atomic.
- *
- * Calling copy_to_user() in atomic context is not desirable. Hence first
- * copying the data to a pre-allocated kernel page and then copying to user
- * space in non-atomic context.
+ * Copy a page from "oldmem". For this page, there might be no pte mapped
+ * in the current kernel.
  */
-ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
-                               size_t csize, unsigned long offset, int userbuf)
+ssize_t copy_oldmem_page(unsigned long pfn, char *buf, size_t csize,
+			 unsigned long offset, int userbuf)
 {
 	void  *vaddr;
 
@ arch/x86/kernel/crash_dump_32.c:56 @ ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
 	if (!is_crashed_pfn_valid(pfn))
 		return -EFAULT;
 
-	vaddr = kmap_atomic_pfn(pfn);
+	vaddr = kmap_local_pfn(pfn);
 
 	if (!userbuf) {
-		memcpy(buf, (vaddr + offset), csize);
-		kunmap_atomic(vaddr);
+		memcpy(buf, vaddr + offset, csize);
 	} else {
-		if (!kdump_buf_page) {
-			printk(KERN_WARNING "Kdump: Kdump buffer page not"
-				" allocated\n");
-			kunmap_atomic(vaddr);
-			return -EFAULT;
-		}
-		copy_page(kdump_buf_page, vaddr);
-		kunmap_atomic(vaddr);
-		if (copy_to_user(buf, (kdump_buf_page + offset), csize))
-			return -EFAULT;
+		if (copy_to_user(buf, vaddr + offset, csize))
+			csize = -EFAULT;
 	}
 
-	return csize;
-}
+	kunmap_local(vaddr);
 
-static int __init kdump_buf_page_init(void)
-{
-	int ret = 0;
-
-	kdump_buf_page = kmalloc(PAGE_SIZE, GFP_KERNEL);
-	if (!kdump_buf_page) {
-		printk(KERN_WARNING "Kdump: Failed to allocate kdump buffer"
-			 " page\n");
-		ret = -ENOMEM;
-	}
-
-	return ret;
+	return csize;
 }
-arch_initcall(kdump_buf_page_init);
@ arch/x86/kernel/fpu/core.c:162 @ void kernel_fpu_end(void)
 }
 EXPORT_SYMBOL_GPL(kernel_fpu_end);
 
+void kernel_fpu_resched(void)
+{
+	WARN_ON_FPU(!this_cpu_read(in_kernel_fpu));
+
+	if (should_resched(PREEMPT_OFFSET)) {
+		kernel_fpu_end();
+		cond_resched();
+		kernel_fpu_begin();
+	}
+}
+EXPORT_SYMBOL_GPL(kernel_fpu_resched);
+
 /*
  * Save the FPU state (mark it for reload if necessary):
  *
@ arch/x86/kernel/irq_32.c:134 @ int irq_init_percpu_irqstack(unsigned int cpu)
 	return 0;
 }
 
+#ifndef CONFIG_PREEMPT_RT
 void do_softirq_own_stack(void)
 {
 	struct irq_stack *irqstk;
@ arch/x86/kernel/irq_32.c:151 @ void do_softirq_own_stack(void)
 
 	call_on_stack(__do_softirq, isp);
 }
+#endif
 
 void __handle_irq(struct irq_desc *desc, struct pt_regs *regs)
 {
@ arch/x86/kernel/irq_64.c:75 @ int irq_init_percpu_irqstack(unsigned int cpu)
 	return map_irq_stack(cpu);
 }
 
+#ifndef CONFIG_PREEMPT_RT
 void do_softirq_own_stack(void)
 {
 	run_on_irqstack_cond(__do_softirq, NULL);
 }
+#endif
@ arch/x86/kvm/x86.c:7978 @ int kvm_arch_init(void *opaque)
 		goto out;
 	}
 
+#ifdef CONFIG_PREEMPT_RT
+	if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) {
+		pr_err("RT requires X86_FEATURE_CONSTANT_TSC\n");
+		r = -EOPNOTSUPP;
+		goto out;
+	}
+#endif
+
 	r = -ENOMEM;
 	x86_fpu_cache = kmem_cache_create("x86_fpu", sizeof(struct fpu),
 					  __alignof__(struct fpu), SLAB_ACCOUNT,
@ arch/x86/mm/highmem_32.c:7 @
 #include <linux/swap.h> /* for totalram_pages */
 #include <linux/memblock.h>
 
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
-	unsigned long vaddr;
-	int idx, type;
-
-	type = kmap_atomic_idx_push();
-	idx = type + KM_TYPE_NR*smp_processor_id();
-	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-	BUG_ON(!pte_none(*(kmap_pte-idx)));
-	set_pte(kmap_pte-idx, mk_pte(page, prot));
-	arch_flush_lazy_mmu_mode();
-
-	return (void *)vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-/*
- * This is the same as kmap_atomic() but can map memory that doesn't
- * have a struct page associated with it.
- */
-void *kmap_atomic_pfn(unsigned long pfn)
-{
-	return kmap_atomic_prot_pfn(pfn, kmap_prot);
-}
-EXPORT_SYMBOL_GPL(kmap_atomic_pfn);
-
-void kunmap_atomic_high(void *kvaddr)
-{
-	unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-
-	if (vaddr >= __fix_to_virt(FIX_KMAP_END) &&
-	    vaddr <= __fix_to_virt(FIX_KMAP_BEGIN)) {
-		int idx, type;
-
-		type = kmap_atomic_idx();
-		idx = type + KM_TYPE_NR * smp_processor_id();
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-		WARN_ON_ONCE(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
-#endif
-		/*
-		 * Force other mappings to Oops if they'll try to access this
-		 * pte without first remap it.  Keeping stale mappings around
-		 * is a bad idea also, in case the page changes cacheability
-		 * attributes or becomes a protected page in a hypervisor.
-		 */
-		kpte_clear_flush(kmap_pte-idx, vaddr);
-		kmap_atomic_idx_pop();
-		arch_flush_lazy_mmu_mode();
-	}
-#ifdef CONFIG_DEBUG_HIGHMEM
-	else {
-		BUG_ON(vaddr < PAGE_OFFSET);
-		BUG_ON(vaddr >= (unsigned long)high_memory);
-	}
-#endif
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
-
 void __init set_highmem_pages_init(void)
 {
 	struct zone *zone;
@ arch/x86/mm/init_32.c:397 @ kernel_physical_mapping_init(unsigned long start,
 	return last_map_addr;
 }
 
-pte_t *kmap_pte;
-
-static void __init kmap_init(void)
-{
-	unsigned long kmap_vstart;
-
-	/*
-	 * Cache the first kmap pte:
-	 */
-	kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
-	kmap_pte = virt_to_kpte(kmap_vstart);
-}
-
 #ifdef CONFIG_HIGHMEM
 static void __init permanent_kmaps_init(pgd_t *pgd_base)
 {
@ arch/x86/mm/init_32.c:702 @ void __init paging_init(void)
 
 	__flush_tlb_all();
 
-	kmap_init();
-
 	/*
 	 * NOTE: at this point the bootmem allocator is fully available.
 	 */
@ arch/x86/mm/iomap_32.c:47 @ void iomap_free(resource_size_t base, unsigned long size)
 }
 EXPORT_SYMBOL_GPL(iomap_free);
 
-void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot)
-{
-	unsigned long vaddr;
-	int idx, type;
-
-	preempt_disable();
-	pagefault_disable();
-
-	type = kmap_atomic_idx_push();
-	idx = type + KM_TYPE_NR * smp_processor_id();
-	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-	set_pte(kmap_pte - idx, pfn_pte(pfn, prot));
-	arch_flush_lazy_mmu_mode();
-
-	return (void *)vaddr;
-}
-
-/*
- * Map 'pfn' using protections 'prot'
- */
-void __iomem *
-iomap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot)
+void __iomem *__iomap_local_pfn_prot(unsigned long pfn, pgprot_t prot)
 {
 	/*
 	 * For non-PAT systems, translate non-WB request to UC- just in
@ arch/x86/mm/iomap_32.c:63 @ iomap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot)
 	/* Filter out unsupported __PAGE_KERNEL* bits: */
 	pgprot_val(prot) &= __default_kernel_pte_mask;
 
-	return (void __force __iomem *) kmap_atomic_prot_pfn(pfn, prot);
-}
-EXPORT_SYMBOL_GPL(iomap_atomic_prot_pfn);
-
-void
-iounmap_atomic(void __iomem *kvaddr)
-{
-	unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-
-	if (vaddr >= __fix_to_virt(FIX_KMAP_END) &&
-	    vaddr <= __fix_to_virt(FIX_KMAP_BEGIN)) {
-		int idx, type;
-
-		type = kmap_atomic_idx();
-		idx = type + KM_TYPE_NR * smp_processor_id();
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-		WARN_ON_ONCE(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
-#endif
-		/*
-		 * Force other mappings to Oops if they'll try to access this
-		 * pte without first remap it.  Keeping stale mappings around
-		 * is a bad idea also, in case the page changes cacheability
-		 * attributes or becomes a protected page in a hypervisor.
-		 */
-		kpte_clear_flush(kmap_pte-idx, vaddr);
-		kmap_atomic_idx_pop();
-	}
-
-	pagefault_enable();
-	preempt_enable();
+	return (void __force __iomem *)__kmap_local_pfn_prot(pfn, prot);
 }
-EXPORT_SYMBOL_GPL(iounmap_atomic);
+EXPORT_SYMBOL_GPL(__iomap_local_pfn_prot);
@ arch/xtensa/Kconfig:669 @ endchoice
 config HIGHMEM
 	bool "High Memory Support"
 	depends on MMU
+	select KMAP_LOCAL
 	help
 	  Linux can use the full amount of RAM in the system by
 	  default. However, the default MMUv2 setup only maps the
@ arch/xtensa/include/asm/fixmap.h:19 @
 #ifdef CONFIG_HIGHMEM
 #include <linux/threads.h>
 #include <linux/pgtable.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
 #endif
 
 /*
@ arch/xtensa/include/asm/fixmap.h:42 @ enum fixed_addresses {
 	/* reserved pte's for temporary kernel mappings */
 	FIX_KMAP_BEGIN,
 	FIX_KMAP_END = FIX_KMAP_BEGIN +
-		(KM_TYPE_NR * NR_CPUS * DCACHE_N_COLORS) - 1,
+		(KM_MAX_IDX * NR_CPUS * DCACHE_N_COLORS) - 1,
 #endif
 	__end_of_fixed_addresses
 };
@ arch/xtensa/include/asm/highmem.h:19 @
 #include <linux/pgtable.h>
 #include <asm/cacheflush.h>
 #include <asm/fixmap.h>
-#include <asm/kmap_types.h>
 
-#define PKMAP_BASE		((FIXADDR_START - \
+#define PKMAP_BASE		((FIXADDR_START -			\
 				  (LAST_PKMAP + 1) * PAGE_SIZE) & PMD_MASK)
 #define LAST_PKMAP		(PTRS_PER_PTE * DCACHE_N_COLORS)
 #define LAST_PKMAP_MASK		(LAST_PKMAP - 1)
@ arch/xtensa/include/asm/highmem.h:70 @ static inline void flush_cache_kmaps(void)
 	flush_cache_all();
 }
 
+enum fixed_addresses kmap_local_map_idx(int type, unsigned long pfn);
+#define arch_kmap_local_map_idx		kmap_local_map_idx
+
+enum fixed_addresses kmap_local_unmap_idx(int type, unsigned long addr);
+#define arch_kmap_local_unmap_idx	kmap_local_unmap_idx
+
+#define arch_kmap_local_post_unmap(vaddr)	\
+	local_flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE)
+
 void kmap_init(void);
 
 #endif
@ arch/xtensa/include/asm/spinlock_types.h:5 @
 #ifndef __ASM_SPINLOCK_TYPES_H
 #define __ASM_SPINLOCK_TYPES_H
 
-#if !defined(__LINUX_SPINLOCK_TYPES_H) && !defined(__ASM_SPINLOCK_H)
-# error "please don't include this file directly"
-#endif
-
 #include <asm-generic/qspinlock_types.h>
 #include <asm-generic/qrwlock_types.h>
 
@ arch/xtensa/mm/highmem.c:15 @
 #include <linux/highmem.h>
 #include <asm/tlbflush.h>
 
-static pte_t *kmap_pte;
-
 #if DCACHE_WAY_SIZE > PAGE_SIZE
 unsigned int last_pkmap_nr_arr[DCACHE_N_COLORS];
 wait_queue_head_t pkmap_map_wait_arr[DCACHE_N_COLORS];
@ arch/xtensa/mm/highmem.c:34 @ static inline void kmap_waitqueues_init(void)
 
 static inline enum fixed_addresses kmap_idx(int type, unsigned long color)
 {
-	return (type + KM_TYPE_NR * smp_processor_id()) * DCACHE_N_COLORS +
+	return (type + KM_MAX_IDX * smp_processor_id()) * DCACHE_N_COLORS +
 		color;
 }
 
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
+enum fixed_addresses kmap_local_map_idx(int type, unsigned long pfn)
 {
-	enum fixed_addresses idx;
-	unsigned long vaddr;
-
-	idx = kmap_idx(kmap_atomic_idx_push(),
-		       DCACHE_ALIAS(page_to_phys(page)));
-	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-#ifdef CONFIG_DEBUG_HIGHMEM
-	BUG_ON(!pte_none(*(kmap_pte + idx)));
-#endif
-	set_pte(kmap_pte + idx, mk_pte(page, prot));
-
-	return (void *)vaddr;
+	return kmap_idx(type, DCACHE_ALIAS(pfn << PAGE_SHIFT));
 }
-EXPORT_SYMBOL(kmap_atomic_high_prot);
 
-void kunmap_atomic_high(void *kvaddr)
+enum fixed_addresses kmap_local_unmap_idx(int type, unsigned long addr)
 {
-	if (kvaddr >= (void *)FIXADDR_START &&
-	    kvaddr < (void *)FIXADDR_TOP) {
-		int idx = kmap_idx(kmap_atomic_idx(),
-				   DCACHE_ALIAS((unsigned long)kvaddr));
-
-		/*
-		 * Force other mappings to Oops if they'll try to access this
-		 * pte without first remap it.  Keeping stale mappings around
-		 * is a bad idea also, in case the page changes cacheability
-		 * attributes or becomes a protected page in a hypervisor.
-		 */
-		pte_clear(&init_mm, kvaddr, kmap_pte + idx);
-		local_flush_tlb_kernel_range((unsigned long)kvaddr,
-					     (unsigned long)kvaddr + PAGE_SIZE);
-
-		kmap_atomic_idx_pop();
-	}
+	return kmap_idx(type, DCACHE_ALIAS(addr));
 }
-EXPORT_SYMBOL(kunmap_atomic_high);
 
 void __init kmap_init(void)
 {
-	unsigned long kmap_vstart;
-
 	/* Check if this memory layout is broken because PKMAP overlaps
 	 * page table.
 	 */
 	BUILD_BUG_ON(PKMAP_BASE < TLBTEMP_BASE_1 + TLBTEMP_SIZE);
-	/* cache the first kmap pte */
-	kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
-	kmap_pte = virt_to_kpte(kmap_vstart);
 	kmap_waitqueues_init();
 }
@ block/blk-mq.c:44 @
 #include "blk-mq-sched.h"
 #include "blk-rq-qos.h"
 
-static DEFINE_PER_CPU(struct list_head, blk_cpu_done);
+static DEFINE_PER_CPU(struct llist_head, blk_cpu_done);
 
 static void blk_mq_poll_stats_start(struct request_queue *q);
 static void blk_mq_poll_stats_fn(struct blk_stat_callback *cb);
@ block/blk-mq.c:568 @ void blk_mq_end_request(struct request *rq, blk_status_t error)
 }
 EXPORT_SYMBOL(blk_mq_end_request);
 
-/*
- * Softirq action handler - move entries to local list and loop over them
- * while passing them to the queue registered handler.
- */
-static __latent_entropy void blk_done_softirq(struct softirq_action *h)
+static void blk_complete_reqs(struct llist_head *list)
 {
-	struct list_head *cpu_list, local_list;
-
-	local_irq_disable();
-	cpu_list = this_cpu_ptr(&blk_cpu_done);
-	list_replace_init(cpu_list, &local_list);
-	local_irq_enable();
-
-	while (!list_empty(&local_list)) {
-		struct request *rq;
+	struct llist_node *entry = llist_reverse_order(llist_del_all(list));
+	struct request *rq, *next;
 
-		rq = list_entry(local_list.next, struct request, ipi_list);
-		list_del_init(&rq->ipi_list);
+	llist_for_each_entry_safe(rq, next, entry, ipi_list)
 		rq->q->mq_ops->complete(rq);
-	}
 }
 
-static void blk_mq_trigger_softirq(struct request *rq)
+static __latent_entropy void blk_done_softirq(struct softirq_action *h)
 {
-	struct list_head *list;
-	unsigned long flags;
-
-	local_irq_save(flags);
-	list = this_cpu_ptr(&blk_cpu_done);
-	list_add_tail(&rq->ipi_list, list);
-
-	/*
-	 * If the list only contains our just added request, signal a raise of
-	 * the softirq.  If there are already entries there, someone already
-	 * raised the irq but it hasn't run yet.
-	 */
-	if (list->next == &rq->ipi_list)
-		raise_softirq_irqoff(BLOCK_SOFTIRQ);
-	local_irq_restore(flags);
+	blk_complete_reqs(this_cpu_ptr(&blk_cpu_done));
 }
 
 static int blk_softirq_cpu_dead(unsigned int cpu)
 {
-	/*
-	 * If a CPU goes away, splice its entries to the current CPU
-	 * and trigger a run of the softirq
-	 */
-	local_irq_disable();
-	list_splice_init(&per_cpu(blk_cpu_done, cpu),
-			 this_cpu_ptr(&blk_cpu_done));
-	raise_softirq_irqoff(BLOCK_SOFTIRQ);
-	local_irq_enable();
-
+	blk_complete_reqs(&per_cpu(blk_cpu_done, cpu));
 	return 0;
 }
 
-
 static void __blk_mq_complete_request_remote(void *data)
 {
-	struct request *rq = data;
-
-	/*
-	 * For most of single queue controllers, there is only one irq vector
-	 * for handling I/O completion, and the only irq's affinity is set
-	 * to all possible CPUs.  On most of ARCHs, this affinity means the irq
-	 * is handled on one specific CPU.
-	 *
-	 * So complete I/O requests in softirq context in case of single queue
-	 * devices to avoid degrading I/O performance due to irqsoff latency.
-	 */
-	if (rq->q->nr_hw_queues == 1)
-		blk_mq_trigger_softirq(rq);
-	else
-		rq->q->mq_ops->complete(rq);
+	__raise_softirq_irqoff(BLOCK_SOFTIRQ);
 }
 
 static inline bool blk_mq_complete_need_ipi(struct request *rq)
@ block/blk-mq.c:600 @ static inline bool blk_mq_complete_need_ipi(struct request *rq)
 	if (!IS_ENABLED(CONFIG_SMP) ||
 	    !test_bit(QUEUE_FLAG_SAME_COMP, &rq->q->queue_flags))
 		return false;
+	/*
+	 * With force threaded interrupts enabled, raising softirq from an SMP
+	 * function call will always result in waking the ksoftirqd thread.
+	 * This is probably worse than completing the request on a different
+	 * cache domain.
+	 */
+	if (force_irqthreads)
+		return false;
 
 	/* same CPU or cache domain?  Complete locally */
 	if (cpu == rq->mq_ctx->cpu ||
@ block/blk-mq.c:619 @ static inline bool blk_mq_complete_need_ipi(struct request *rq)
 	return cpu_online(rq->mq_ctx->cpu);
 }
 
+static void blk_mq_complete_send_ipi(struct request *rq)
+{
+	struct llist_head *list;
+	unsigned int cpu;
+
+	cpu = rq->mq_ctx->cpu;
+	list = &per_cpu(blk_cpu_done, cpu);
+	if (llist_add(&rq->ipi_list, list)) {
+		rq->csd.func = __blk_mq_complete_request_remote;
+		rq->csd.info = rq;
+		rq->csd.flags = 0;
+		smp_call_function_single_async(cpu, &rq->csd);
+	}
+}
+
+static void blk_mq_raise_softirq(struct request *rq)
+{
+	struct llist_head *list;
+
+	preempt_disable();
+	list = this_cpu_ptr(&blk_cpu_done);
+	if (llist_add(&rq->ipi_list, list))
+		raise_softirq(BLOCK_SOFTIRQ);
+	preempt_enable();
+}
+
 bool blk_mq_complete_request_remote(struct request *rq)
 {
 	WRITE_ONCE(rq->state, MQ_RQ_COMPLETE);
@ block/blk-mq.c:657 @ bool blk_mq_complete_request_remote(struct request *rq)
 		return false;
 
 	if (blk_mq_complete_need_ipi(rq)) {
-		rq->csd.func = __blk_mq_complete_request_remote;
-		rq->csd.info = rq;
-		rq->csd.flags = 0;
-		smp_call_function_single_async(rq->mq_ctx->cpu, &rq->csd);
-	} else {
-		if (rq->q->nr_hw_queues > 1)
-			return false;
-		blk_mq_trigger_softirq(rq);
+		blk_mq_complete_send_ipi(rq);
+		return true;
 	}
 
-	return true;
+	if (rq->q->nr_hw_queues == 1) {
+		blk_mq_raise_softirq(rq);
+		return true;
+	}
+	return false;
 }
 EXPORT_SYMBOL_GPL(blk_mq_complete_request_remote);
 
@ block/blk-mq.c:1573 @ static void __blk_mq_delay_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async,
 		return;
 
 	if (!async && !(hctx->flags & BLK_MQ_F_BLOCKING)) {
-		int cpu = get_cpu();
+		int cpu = get_cpu_light();
 		if (cpumask_test_cpu(cpu, hctx->cpumask)) {
 			__blk_mq_run_hw_queue(hctx);
-			put_cpu();
+			put_cpu_light();
 			return;
 		}
 
-		put_cpu();
+		put_cpu_light();
 	}
 
 	kblockd_mod_delayed_work_on(blk_mq_hctx_next_cpu(hctx), &hctx->run_work,
@ block/blk-mq.c:3963 @ static int __init blk_mq_init(void)
 	int i;
 
 	for_each_possible_cpu(i)
-		INIT_LIST_HEAD(&per_cpu(blk_cpu_done, i));
+		init_llist_head(&per_cpu(blk_cpu_done, i));
 	open_softirq(BLOCK_SOFTIRQ, blk_done_softirq);
 
 	cpuhp_setup_state_nocalls(CPUHP_BLOCK_SOFTIRQ_DEAD,
@ crypto/cryptd.c:39 @ static struct workqueue_struct *cryptd_wq;
 struct cryptd_cpu_queue {
 	struct crypto_queue queue;
 	struct work_struct work;
+	spinlock_t qlock;
 };
 
 struct cryptd_queue {
@ crypto/cryptd.c:109 @ static int cryptd_init_queue(struct cryptd_queue *queue,
 		cpu_queue = per_cpu_ptr(queue->cpu_queue, cpu);
 		crypto_init_queue(&cpu_queue->queue, max_cpu_qlen);
 		INIT_WORK(&cpu_queue->work, cryptd_queue_worker);
+		spin_lock_init(&cpu_queue->qlock);
 	}
 	pr_info("cryptd: max_cpu_qlen set to %d\n", max_cpu_qlen);
 	return 0;
@ crypto/cryptd.c:134 @ static int cryptd_enqueue_request(struct cryptd_queue *queue,
 	struct cryptd_cpu_queue *cpu_queue;
 	refcount_t *refcnt;
 
-	cpu = get_cpu();
-	cpu_queue = this_cpu_ptr(queue->cpu_queue);
+	cpu_queue = raw_cpu_ptr(queue->cpu_queue);
+	spin_lock_bh(&cpu_queue->qlock);
+	cpu = smp_processor_id();
+
 	err = crypto_enqueue_request(&cpu_queue->queue, request);
 
 	refcnt = crypto_tfm_ctx(request->tfm);
@ crypto/cryptd.c:153 @ static int cryptd_enqueue_request(struct cryptd_queue *queue,
 	refcount_inc(refcnt);
 
 out_put_cpu:
-	put_cpu();
+	spin_unlock_bh(&cpu_queue->qlock);
 
 	return err;
 }
@ crypto/cryptd.c:169 @ static void cryptd_queue_worker(struct work_struct *work)
 	cpu_queue = container_of(work, struct cryptd_cpu_queue, work);
 	/*
 	 * Only handle one request at a time to avoid hogging crypto workqueue.
-	 * preempt_disable/enable is used to prevent being preempted by
-	 * cryptd_enqueue_request(). local_bh_disable/enable is used to prevent
-	 * cryptd_enqueue_request() being accessed from software interrupts.
 	 */
-	local_bh_disable();
-	preempt_disable();
+	spin_lock_bh(&cpu_queue->qlock);
 	backlog = crypto_get_backlog(&cpu_queue->queue);
 	req = crypto_dequeue_request(&cpu_queue->queue);
-	preempt_enable();
-	local_bh_enable();
+	spin_unlock_bh(&cpu_queue->qlock);
 
 	if (!req)
 		return;
@ drivers/atm/eni.c:2057 @ static int eni_send(struct atm_vcc *vcc,struct sk_buff *skb)
 	}
 	submitted++;
 	ATM_SKB(skb)->vcc = vcc;
-	tasklet_disable(&ENI_DEV(vcc->dev)->task);
+	tasklet_disable_in_atomic(&ENI_DEV(vcc->dev)->task);
 	res = do_tx(skb);
 	tasklet_enable(&ENI_DEV(vcc->dev)->task);
 	if (res == enq_ok) return 0;
@ drivers/block/zram/zram_drv.c:62 @ static void zram_free_page(struct zram *zram, size_t index);
 static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec,
 				u32 index, int offset, struct bio *bio);
 
+#ifdef CONFIG_PREEMPT_RT
+static void zram_meta_init_table_locks(struct zram *zram, size_t num_pages)
+{
+	size_t index;
+
+	for (index = 0; index < num_pages; index++)
+		spin_lock_init(&zram->table[index].lock);
+}
+
+static int zram_slot_trylock(struct zram *zram, u32 index)
+{
+	int ret;
+
+	ret = spin_trylock(&zram->table[index].lock);
+	if (ret)
+		__set_bit(ZRAM_LOCK, &zram->table[index].flags);
+	return ret;
+}
+
+static void zram_slot_lock(struct zram *zram, u32 index)
+{
+	spin_lock(&zram->table[index].lock);
+	__set_bit(ZRAM_LOCK, &zram->table[index].flags);
+}
+
+static void zram_slot_unlock(struct zram *zram, u32 index)
+{
+	__clear_bit(ZRAM_LOCK, &zram->table[index].flags);
+	spin_unlock(&zram->table[index].lock);
+}
+
+#else
+
+static void zram_meta_init_table_locks(struct zram *zram, size_t num_pages) { }
 
 static int zram_slot_trylock(struct zram *zram, u32 index)
 {
@ drivers/block/zram/zram_drv.c:111 @ static void zram_slot_unlock(struct zram *zram, u32 index)
 {
 	bit_spin_unlock(ZRAM_LOCK, &zram->table[index].flags);
 }
+#endif
 
 static inline bool init_done(struct zram *zram)
 {
@ drivers/block/zram/zram_drv.c:1203 @ static bool zram_meta_alloc(struct zram *zram, u64 disksize)
 
 	if (!huge_class_size)
 		huge_class_size = zs_huge_class_size(zram->mem_pool);
+	zram_meta_init_table_locks(zram, num_pages);
 	return true;
 }
 
@ drivers/block/zram/zram_drv.h:66 @ struct zram_table_entry {
 		unsigned long element;
 	};
 	unsigned long flags;
+	spinlock_t lock;
 #ifdef CONFIG_ZRAM_MEMORY_TRACKING
 	ktime_t ac_time;
 #endif
@ drivers/char/random.c:1255 @ static __u32 get_reg(struct fast_pool *f, struct pt_regs *regs)
 	return *ptr;
 }
 
-void add_interrupt_randomness(int irq, int irq_flags)
+void add_interrupt_randomness(int irq, int irq_flags, __u64 ip)
 {
 	struct entropy_store	*r;
 	struct fast_pool	*fast_pool = this_cpu_ptr(&irq_randomness);
-	struct pt_regs		*regs = get_irq_regs();
 	unsigned long		now = jiffies;
 	cycles_t		cycles = random_get_entropy();
 	__u32			c_high, j_high;
-	__u64			ip;
 	unsigned long		seed;
 	int			credit = 0;
 
 	if (cycles == 0)
-		cycles = get_reg(fast_pool, regs);
+		cycles = get_reg(fast_pool, NULL);
 	c_high = (sizeof(cycles) > 4) ? cycles >> 32 : 0;
 	j_high = (sizeof(now) > 4) ? now >> 32 : 0;
 	fast_pool->pool[0] ^= cycles ^ j_high ^ irq;
 	fast_pool->pool[1] ^= now ^ c_high;
-	ip = regs ? instruction_pointer(regs) : _RET_IP_;
+	if (!ip)
+		ip = _RET_IP_;
 	fast_pool->pool[2] ^= ip;
 	fast_pool->pool[3] ^= (sizeof(ip) > 4) ? ip >> 32 :
-		get_reg(fast_pool, regs);
+		get_reg(fast_pool, NULL);
 
 	fast_mix(fast_pool);
 	add_interrupt_bench(cycles);
@ drivers/char/tpm/tpm-dev-common.c:23 @
 #include "tpm-dev.h"
 
 static struct workqueue_struct *tpm_dev_wq;
-static DEFINE_MUTEX(tpm_dev_wq_lock);
 
 static ssize_t tpm_dev_transmit(struct tpm_chip *chip, struct tpm_space *space,
 				u8 *buf, size_t bufsiz)
@ drivers/char/tpm/tpm_tis.c:53 @ static inline struct tpm_tis_tcg_phy *to_tpm_tis_tcg_phy(struct tpm_tis_data *da
 	return container_of(data, struct tpm_tis_tcg_phy, priv);
 }
 
+#ifdef CONFIG_PREEMPT_RT
+/*
+ * Flushes previous write operations to chip so that a subsequent
+ * ioread*()s won't stall a cpu.
+ */
+static inline void tpm_tis_flush(void __iomem *iobase)
+{
+	ioread8(iobase + TPM_ACCESS(0));
+}
+#else
+#define tpm_tis_flush(iobase) do { } while (0)
+#endif
+
+static inline void tpm_tis_iowrite8(u8 b, void __iomem *iobase, u32 addr)
+{
+	iowrite8(b, iobase + addr);
+	tpm_tis_flush(iobase);
+}
+
+static inline void tpm_tis_iowrite32(u32 b, void __iomem *iobase, u32 addr)
+{
+	iowrite32(b, iobase + addr);
+	tpm_tis_flush(iobase);
+}
+
 static int interrupts = -1;
 module_param(interrupts, int, 0444);
 MODULE_PARM_DESC(interrupts, "Enable interrupts");
@ drivers/char/tpm/tpm_tis.c:197 @ static int tpm_tcg_write_bytes(struct tpm_tis_data *data, u32 addr, u16 len,
 	struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 
 	while (len--)
-		iowrite8(*value++, phy->iobase + addr);
+		tpm_tis_iowrite8(*value++, phy->iobase, addr);
 
 	return 0;
 }
@ drivers/char/tpm/tpm_tis.c:224 @ static int tpm_tcg_write32(struct tpm_tis_data *data, u32 addr, u32 value)
 {
 	struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 
-	iowrite32(value, phy->iobase + addr);
+	tpm_tis_iowrite32(value, phy->iobase, addr);
 
 	return 0;
 }
@ drivers/firewire/ohci.c:2548 @ static int ohci_cancel_packet(struct fw_card *card, struct fw_packet *packet)
 	struct driver_data *driver_data = packet->driver_data;
 	int ret = -ENOENT;
 
-	tasklet_disable(&ctx->tasklet);
+	tasklet_disable_in_atomic(&ctx->tasklet);
 
 	if (packet->ack != 0)
 		goto out;
@ drivers/firewire/ohci.c:3468 @ static int ohci_flush_iso_completions(struct fw_iso_context *base)
 	struct iso_context *ctx = container_of(base, struct iso_context, base);
 	int ret = 0;
 
-	tasklet_disable(&ctx->context.tasklet);
+	tasklet_disable_in_atomic(&ctx->context.tasklet);
 
 	if (!test_and_set_bit_lock(0, &ctx->flushing_completions)) {
 		context_tasklet((unsigned long)&ctx->context);
@ drivers/firmware/efi/efi.c:69 @ struct mm_struct efi_mm = {
 
 struct workqueue_struct *efi_rts_wq;
 
-static bool disable_runtime;
+static bool disable_runtime = IS_ENABLED(CONFIG_PREEMPT_RT);
 static int __init setup_noefi(char *arg)
 {
 	disable_runtime = true;
@ drivers/firmware/efi/efi.c:100 @ static int __init parse_efi_cmdline(char *str)
 	if (parse_option_str(str, "noruntime"))
 		disable_runtime = true;
 
+	if (parse_option_str(str, "runtime"))
+		disable_runtime = false;
+
 	if (parse_option_str(str, "nosoftreserve"))
 		set_bit(EFI_MEM_NO_SOFT_RESERVE, &efi.flags);
 
@ drivers/gpu/drm/i915/display/intel_sprite.c:121 @ void intel_pipe_update_start(const struct intel_crtc_state *new_crtc_state)
 			"PSR idle timed out 0x%x, atomic update may fail\n",
 			psr_status);
 
-	local_irq_disable();
+	if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+		local_irq_disable();
 
 	crtc->debug.min_vbl = min;
 	crtc->debug.max_vbl = max;
@ drivers/gpu/drm/i915/display/intel_sprite.c:147 @ void intel_pipe_update_start(const struct intel_crtc_state *new_crtc_state)
 			break;
 		}
 
-		local_irq_enable();
+		if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+			local_irq_enable();
 
 		timeout = schedule_timeout(timeout);
 
-		local_irq_disable();
+		if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+			local_irq_disable();
 	}
 
 	finish_wait(wq, &wait);
@ drivers/gpu/drm/i915/display/intel_sprite.c:186 @ void intel_pipe_update_start(const struct intel_crtc_state *new_crtc_state)
 	return;
 
 irq_disable:
-	local_irq_disable();
+	if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+		local_irq_disable();
 }
 
 /**
@ drivers/gpu/drm/i915/display/intel_sprite.c:225 @ void intel_pipe_update_end(struct intel_crtc_state *new_crtc_state)
 		new_crtc_state->uapi.event = NULL;
 	}
 
-	local_irq_enable();
+	if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+		local_irq_enable();
 
 	if (intel_vgpu_active(dev_priv))
 		return;
@ drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c:1083 @ static void reloc_cache_reset(struct reloc_cache *cache, struct i915_execbuffer
 		struct i915_ggtt *ggtt = cache_to_ggtt(cache);
 
 		intel_gt_flush_ggtt_writes(ggtt->vm.gt);
-		io_mapping_unmap_atomic((void __iomem *)vaddr);
+		io_mapping_unmap_local((void __iomem *)vaddr);
 
 		if (drm_mm_node_allocated(&cache->node)) {
 			ggtt->vm.clear_range(&ggtt->vm,
@ drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c:1149 @ static void *reloc_iomap(struct drm_i915_gem_object *obj,
 
 	if (cache->vaddr) {
 		intel_gt_flush_ggtt_writes(ggtt->vm.gt);
-		io_mapping_unmap_atomic((void __force __iomem *) unmask_page(cache->vaddr));
+		io_mapping_unmap_local((void __force __iomem *) unmask_page(cache->vaddr));
 	} else {
 		struct i915_vma *vma;
 		int err;
@ drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c:1197 @ static void *reloc_iomap(struct drm_i915_gem_object *obj,
 		offset += page << PAGE_SHIFT;
 	}
 
-	vaddr = (void __force *)io_mapping_map_atomic_wc(&ggtt->iomap,
-							 offset);
+	vaddr = (void __force *)io_mapping_map_local_wc(&ggtt->iomap, offset);
 	cache->page = page;
 	cache->vaddr = (unsigned long)vaddr;
 
@ drivers/gpu/drm/i915/gt/intel_breadcrumbs.c:345 @ void intel_breadcrumbs_park(struct intel_breadcrumbs *b)
 	/* Kick the work once more to drain the signalers */
 	irq_work_sync(&b->irq_work);
 	while (unlikely(READ_ONCE(b->irq_armed))) {
-		local_irq_disable();
-		signal_irq_work(&b->irq_work);
-		local_irq_enable();
+		irq_work_queue(&b->irq_work);
 		cond_resched();
+		irq_work_sync(&b->irq_work);
 	}
 	GEM_BUG_ON(!list_empty(&b->signalers));
 }
@ drivers/gpu/drm/i915/gt/intel_engine_pm.c:63 @ static int __engine_unpark(struct intel_wakeref *wf)
 
 static inline unsigned long __timeline_mark_lock(struct intel_context *ce)
 {
-	unsigned long flags;
+	unsigned long flags = 0;
 
-	local_irq_save(flags);
+	if (!force_irqthreads)
+		local_irq_save(flags);
 	mutex_acquire(&ce->timeline->mutex.dep_map, 2, 0, _THIS_IP_);
 
 	return flags;
@ drivers/gpu/drm/i915/gt/intel_engine_pm.c:76 @ static inline void __timeline_mark_unlock(struct intel_context *ce,
 					  unsigned long flags)
 {
 	mutex_release(&ce->timeline->mutex.dep_map, _THIS_IP_);
-	local_irq_restore(flags);
+	if (!force_irqthreads)
+		local_irq_restore(flags);
 }
 
 #else
@ drivers/gpu/drm/i915/i915_gem.c:358 @ gtt_user_read(struct io_mapping *mapping,
 	      char __user *user_data, int length)
 {
 	void __iomem *vaddr;
-	unsigned long unwritten;
+	bool fail = false;
 
 	/* We can use the cpu mem copy function because this is X86. */
-	vaddr = io_mapping_map_atomic_wc(mapping, base);
-	unwritten = __copy_to_user_inatomic(user_data,
-					    (void __force *)vaddr + offset,
-					    length);
-	io_mapping_unmap_atomic(vaddr);
-	if (unwritten) {
-		vaddr = io_mapping_map_wc(mapping, base, PAGE_SIZE);
-		unwritten = copy_to_user(user_data,
-					 (void __force *)vaddr + offset,
-					 length);
-		io_mapping_unmap(vaddr);
-	}
-	return unwritten;
+	vaddr = io_mapping_map_local_wc(mapping, base);
+	if (copy_to_user(user_data, (void __force *)vaddr + offset, length))
+		fail = true;
+	io_mapping_unmap_local(vaddr);
+
+	return fail;
 }
 
 static int
@ drivers/gpu/drm/i915/i915_gem.c:535 @ ggtt_write(struct io_mapping *mapping,
 	   char __user *user_data, int length)
 {
 	void __iomem *vaddr;
-	unsigned long unwritten;
+	bool fail = false;
 
 	/* We can use the cpu mem copy function because this is X86. */
-	vaddr = io_mapping_map_atomic_wc(mapping, base);
-	unwritten = __copy_from_user_inatomic_nocache((void __force *)vaddr + offset,
-						      user_data, length);
-	io_mapping_unmap_atomic(vaddr);
-	if (unwritten) {
-		vaddr = io_mapping_map_wc(mapping, base, PAGE_SIZE);
-		unwritten = copy_from_user((void __force *)vaddr + offset,
-					   user_data, length);
-		io_mapping_unmap(vaddr);
-	}
-
-	return unwritten;
+	vaddr = io_mapping_map_local_wc(mapping, base);
+	if (copy_from_user((void __force *)vaddr + offset, user_data, length))
+		fail = true;
+	io_mapping_unmap_local(vaddr);
+	return fail;
 }
 
 /**
@ drivers/gpu/drm/i915/i915_irq.c:850 @ static bool i915_get_crtc_scanoutpos(struct drm_crtc *_crtc,
 	spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
 
 	/* preempt_disable_rt() should go right here in PREEMPT_RT patchset. */
+	preempt_disable_rt();
 
 	/* Get optional system timestamp before query. */
 	if (stime)
@ drivers/gpu/drm/i915/i915_irq.c:902 @ static bool i915_get_crtc_scanoutpos(struct drm_crtc *_crtc,
 		*etime = ktime_get();
 
 	/* preempt_enable_rt() should go right here in PREEMPT_RT patchset. */
+	preempt_enable_rt();
 
 	spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
 
@ drivers/gpu/drm/i915/i915_trace.h:5 @
 #if !defined(_I915_TRACE_H_) || defined(TRACE_HEADER_MULTI_READ)
 #define _I915_TRACE_H_
 
+#ifdef CONFIG_PREEMPT_RT
+#define NOTRACE
+#endif
+
 #include <linux/stringify.h>
 #include <linux/types.h>
 #include <linux/tracepoint.h>
@ drivers/gpu/drm/i915/i915_trace.h:785 @ DEFINE_EVENT(i915_request, i915_request_add,
 	    TP_ARGS(rq)
 );
 
-#if defined(CONFIG_DRM_I915_LOW_LEVEL_TRACEPOINTS)
+#if defined(CONFIG_DRM_I915_LOW_LEVEL_TRACEPOINTS) && !defined(NOTRACE)
 DEFINE_EVENT(i915_request, i915_request_submit,
 	     TP_PROTO(struct i915_request *rq),
 	     TP_ARGS(rq)
@ drivers/gpu/drm/i915/selftests/i915_gem.c:60 @ static void trash_stolen(struct drm_i915_private *i915)
 
 		ggtt->vm.insert_page(&ggtt->vm, dma, slot, I915_CACHE_NONE, 0);
 
-		s = io_mapping_map_atomic_wc(&ggtt->iomap, slot);
+		s = io_mapping_map_local_wc(&ggtt->iomap, slot);
 		for (x = 0; x < PAGE_SIZE / sizeof(u32); x++) {
 			prng = next_pseudo_random32(prng);
 			iowrite32(prng, &s[x]);
 		}
-		io_mapping_unmap_atomic(s);
+		io_mapping_unmap_local(s);
 	}
 
 	ggtt->vm.clear_range(&ggtt->vm, slot, PAGE_SIZE);
@ drivers/gpu/drm/i915/selftests/i915_gem_gtt.c:1204 @ static int igt_ggtt_page(void *arg)
 		u64 offset = tmp.start + order[n] * PAGE_SIZE;
 		u32 __iomem *vaddr;
 
-		vaddr = io_mapping_map_atomic_wc(&ggtt->iomap, offset);
+		vaddr = io_mapping_map_local_wc(&ggtt->iomap, offset);
 		iowrite32(n, vaddr + n);
-		io_mapping_unmap_atomic(vaddr);
+		io_mapping_unmap_local(vaddr);
 	}
 	intel_gt_flush_ggtt_writes(ggtt->vm.gt);
 
@ drivers/gpu/drm/i915/selftests/i915_gem_gtt.c:1216 @ static int igt_ggtt_page(void *arg)
 		u32 __iomem *vaddr;
 		u32 val;
 
-		vaddr = io_mapping_map_atomic_wc(&ggtt->iomap, offset);
+		vaddr = io_mapping_map_local_wc(&ggtt->iomap, offset);
 		val = ioread32(vaddr + n);
-		io_mapping_unmap_atomic(vaddr);
+		io_mapping_unmap_local(vaddr);
 
 		if (val != n) {
 			pr_err("insert page failed: found %d, expected %d\n",
@ drivers/gpu/drm/nouveau/nvkm/subdev/devinit/fbmem.h:63 @ fbmem_fini(struct io_mapping *fb)
 static inline u32
 fbmem_peek(struct io_mapping *fb, u32 off)
 {
-	u8 __iomem *p = io_mapping_map_atomic_wc(fb, off & PAGE_MASK);
+	u8 __iomem *p = io_mapping_map_local_wc(fb, off & PAGE_MASK);
 	u32 val = ioread32(p + (off & ~PAGE_MASK));
-	io_mapping_unmap_atomic(p);
+	io_mapping_unmap_local(p);
 	return val;
 }
 
 static inline void
 fbmem_poke(struct io_mapping *fb, u32 off, u32 val)
 {
-	u8 __iomem *p = io_mapping_map_atomic_wc(fb, off & PAGE_MASK);
+	u8 __iomem *p = io_mapping_map_local_wc(fb, off & PAGE_MASK);
 	iowrite32(val, p + (off & ~PAGE_MASK));
 	wmb();
-	io_mapping_unmap_atomic(p);
+	io_mapping_unmap_local(p);
 }
 
 static inline bool
@ drivers/gpu/drm/qxl/qxl_image.c:127 @ qxl_image_init_helper(struct qxl_device *qdev,
 				  wrong (check the bitmaps are sent correctly
 				  first) */
 
-	ptr = qxl_bo_kmap_atomic_page(qdev, chunk_bo, 0);
+	ptr = qxl_bo_kmap_local_page(qdev, chunk_bo, 0);
 	chunk = ptr;
 	chunk->data_size = height * chunk_stride;
 	chunk->prev_chunk = 0;
 	chunk->next_chunk = 0;
-	qxl_bo_kunmap_atomic_page(qdev, chunk_bo, ptr);
+	qxl_bo_kunmap_local_page(qdev, chunk_bo, ptr);
 
 	{
 		void *k_data, *i_data;
@ drivers/gpu/drm/qxl/qxl_image.c:146 @ qxl_image_init_helper(struct qxl_device *qdev,
 			i_data = (void *)data;
 
 			while (remain > 0) {
-				ptr = qxl_bo_kmap_atomic_page(qdev, chunk_bo, page << PAGE_SHIFT);
+				ptr = qxl_bo_kmap_local_page(qdev, chunk_bo, page << PAGE_SHIFT);
 
 				if (page == 0) {
 					chunk = ptr;
@ drivers/gpu/drm/qxl/qxl_image.c:160 @ qxl_image_init_helper(struct qxl_device *qdev,
 
 				memcpy(k_data, i_data, size);
 
-				qxl_bo_kunmap_atomic_page(qdev, chunk_bo, ptr);
+				qxl_bo_kunmap_local_page(qdev, chunk_bo, ptr);
 				i_data += size;
 				remain -= size;
 				page++;
@ drivers/gpu/drm/qxl/qxl_image.c:178 @ qxl_image_init_helper(struct qxl_device *qdev,
 					page_offset = offset_in_page(out_offset);
 					size = min((int)(PAGE_SIZE - page_offset), remain);
 
-					ptr = qxl_bo_kmap_atomic_page(qdev, chunk_bo, page_base);
+					ptr = qxl_bo_kmap_local_page(qdev, chunk_bo, page_base);
 					k_data = ptr + page_offset;
 					memcpy(k_data, i_data, size);
-					qxl_bo_kunmap_atomic_page(qdev, chunk_bo, ptr);
+					qxl_bo_kunmap_local_page(qdev, chunk_bo, ptr);
 					remain -= size;
 					i_data += size;
 					out_offset += size;
@ drivers/gpu/drm/qxl/qxl_image.c:192 @ qxl_image_init_helper(struct qxl_device *qdev,
 	qxl_bo_kunmap(chunk_bo);
 
 	image_bo = dimage->bo;
-	ptr = qxl_bo_kmap_atomic_page(qdev, image_bo, 0);
+	ptr = qxl_bo_kmap_local_page(qdev, image_bo, 0);
 	image = ptr;
 
 	image->descriptor.id = 0;
@ drivers/gpu/drm/qxl/qxl_image.c:215 @ qxl_image_init_helper(struct qxl_device *qdev,
 		break;
 	default:
 		DRM_ERROR("unsupported image bit depth\n");
-		qxl_bo_kunmap_atomic_page(qdev, image_bo, ptr);
+		qxl_bo_kunmap_local_page(qdev, image_bo, ptr);
 		return -EINVAL;
 	}
 	image->u.bitmap.flags = QXL_BITMAP_TOP_DOWN;
@ drivers/gpu/drm/qxl/qxl_image.c:225 @ qxl_image_init_helper(struct qxl_device *qdev,
 	image->u.bitmap.palette = 0;
 	image->u.bitmap.data = qxl_bo_physical_address(qdev, chunk_bo, 0);
 
-	qxl_bo_kunmap_atomic_page(qdev, image_bo, ptr);
+	qxl_bo_kunmap_local_page(qdev, image_bo, ptr);
 
 	return 0;
 }
@ drivers/gpu/drm/qxl/qxl_ioctl.c:92 @ apply_reloc(struct qxl_device *qdev, struct qxl_reloc_info *info)
 {
 	void *reloc_page;
 
-	reloc_page = qxl_bo_kmap_atomic_page(qdev, info->dst_bo, info->dst_offset & PAGE_MASK);
+	reloc_page = qxl_bo_kmap_local_page(qdev, info->dst_bo, info->dst_offset & PAGE_MASK);
 	*(uint64_t *)(reloc_page + (info->dst_offset & ~PAGE_MASK)) = qxl_bo_physical_address(qdev,
 											      info->src_bo,
 											      info->src_offset);
-	qxl_bo_kunmap_atomic_page(qdev, info->dst_bo, reloc_page);
+	qxl_bo_kunmap_local_page(qdev, info->dst_bo, reloc_page);
 }
 
 static void
@ drivers/gpu/drm/qxl/qxl_ioctl.c:108 @ apply_surf_reloc(struct qxl_device *qdev, struct qxl_reloc_info *info)
 	if (info->src_bo && !info->src_bo->is_primary)
 		id = info->src_bo->surface_id;
 
-	reloc_page = qxl_bo_kmap_atomic_page(qdev, info->dst_bo, info->dst_offset & PAGE_MASK);
+	reloc_page = qxl_bo_kmap_local_page(qdev, info->dst_bo, info->dst_offset & PAGE_MASK);
 	*(uint32_t *)(reloc_page + (info->dst_offset & ~PAGE_MASK)) = id;
-	qxl_bo_kunmap_atomic_page(qdev, info->dst_bo, reloc_page);
+	qxl_bo_kunmap_local_page(qdev, info->dst_bo, reloc_page);
 }
 
 /* return holding the reference to this object */
@ drivers/gpu/drm/qxl/qxl_ioctl.c:152 @ static int qxl_process_single_command(struct qxl_device *qdev,
 	struct qxl_bo *cmd_bo;
 	void *fb_cmd;
 	int i, ret, num_relocs;
-	int unwritten;
 
 	switch (cmd->type) {
 	case QXL_CMD_DRAW:
@ drivers/gpu/drm/qxl/qxl_ioctl.c:187 @ static int qxl_process_single_command(struct qxl_device *qdev,
 		goto out_free_reloc;
 
 	/* TODO copy slow path code from i915 */
-	fb_cmd = qxl_bo_kmap_atomic_page(qdev, cmd_bo, (release->release_offset & PAGE_MASK));
-	unwritten = __copy_from_user_inatomic_nocache
-		(fb_cmd + sizeof(union qxl_release_info) + (release->release_offset & ~PAGE_MASK),
-		 u64_to_user_ptr(cmd->command), cmd->command_size);
+	fb_cmd = qxl_bo_kmap_local_page(qdev, cmd_bo, (release->release_offset & PAGE_MASK));
 
-	{
+	if (copy_from_user(fb_cmd + sizeof(union qxl_release_info) +
+			   (release->release_offset & ~PAGE_MASK),
+			   u64_to_user_ptr(cmd->command), cmd->command_size)) {
+		ret = -EFAULT;
+	} else {
 		struct qxl_drawable *draw = fb_cmd;
 
 		draw->mm_time = qdev->rom->mm_clock;
 	}
 
-	qxl_bo_kunmap_atomic_page(qdev, cmd_bo, fb_cmd);
-	if (unwritten) {
-		DRM_ERROR("got unwritten %d\n", unwritten);
-		ret = -EFAULT;
+	qxl_bo_kunmap_local_page(qdev, cmd_bo, fb_cmd);
+	if (ret) {
+		DRM_ERROR("copy from user failed %d\n", ret);
 		goto out_free_release;
 	}
 
@ drivers/gpu/drm/qxl/qxl_object.c:176 @ int qxl_bo_kmap(struct qxl_bo *bo, void **ptr)
 	return 0;
 }
 
-void *qxl_bo_kmap_atomic_page(struct qxl_device *qdev,
-			      struct qxl_bo *bo, int page_offset)
+void *qxl_bo_kmap_local_page(struct qxl_device *qdev,
+			     struct qxl_bo *bo, int page_offset)
 {
 	unsigned long offset;
 	void *rptr;
@ drivers/gpu/drm/qxl/qxl_object.c:192 @ void *qxl_bo_kmap_atomic_page(struct qxl_device *qdev,
 		goto fallback;
 
 	offset = bo->tbo.mem.start << PAGE_SHIFT;
-	return io_mapping_map_atomic_wc(map, offset + page_offset);
+	return io_mapping_map_local_wc(map, offset + page_offset);
 fallback:
 	if (bo->kptr) {
 		rptr = bo->kptr + (page_offset * PAGE_SIZE);
@ drivers/gpu/drm/qxl/qxl_object.c:218 @ void qxl_bo_kunmap(struct qxl_bo *bo)
 	ttm_bo_kunmap(&bo->kmap);
 }
 
-void qxl_bo_kunmap_atomic_page(struct qxl_device *qdev,
-			       struct qxl_bo *bo, void *pmap)
+void qxl_bo_kunmap_local_page(struct qxl_device *qdev,
+			      struct qxl_bo *bo, void *pmap)
 {
 	if ((bo->tbo.mem.mem_type != TTM_PL_VRAM) &&
 	    (bo->tbo.mem.mem_type != TTM_PL_PRIV))
 		goto fallback;
 
-	io_mapping_unmap_atomic(pmap);
+	io_mapping_unmap_local(pmap);
 	return;
  fallback:
 	qxl_bo_kunmap(bo);
@ drivers/gpu/drm/qxl/qxl_object.h:92 @ extern int qxl_bo_create(struct qxl_device *qdev,
 			 struct qxl_bo **bo_ptr);
 extern int qxl_bo_kmap(struct qxl_bo *bo, void **ptr);
 extern void qxl_bo_kunmap(struct qxl_bo *bo);
-void *qxl_bo_kmap_atomic_page(struct qxl_device *qdev, struct qxl_bo *bo, int page_offset);
-void qxl_bo_kunmap_atomic_page(struct qxl_device *qdev, struct qxl_bo *bo, void *map);
+void *qxl_bo_kmap_local_page(struct qxl_device *qdev, struct qxl_bo *bo, int page_offset);
+void qxl_bo_kunmap_local_page(struct qxl_device *qdev, struct qxl_bo *bo, void *map);
 extern struct qxl_bo *qxl_bo_ref(struct qxl_bo *bo);
 extern void qxl_bo_unref(struct qxl_bo **bo);
 extern int qxl_bo_pin(struct qxl_bo *bo);
@ drivers/gpu/drm/qxl/qxl_release.c:417 @ union qxl_release_info *qxl_release_map(struct qxl_device *qdev,
 	union qxl_release_info *info;
 	struct qxl_bo *bo = release->release_bo;
 
-	ptr = qxl_bo_kmap_atomic_page(qdev, bo, release->release_offset & PAGE_MASK);
+	ptr = qxl_bo_kmap_local_page(qdev, bo, release->release_offset & PAGE_MASK);
 	if (!ptr)
 		return NULL;
 	info = ptr + (release->release_offset & ~PAGE_MASK);
@ drivers/gpu/drm/qxl/qxl_release.c:432 @ void qxl_release_unmap(struct qxl_device *qdev,
 	void *ptr;
 
 	ptr = ((void *)info) - (release->release_offset & ~PAGE_MASK);
-	qxl_bo_kunmap_atomic_page(qdev, bo, ptr);
+	qxl_bo_kunmap_local_page(qdev, bo, ptr);
 }
 
 void qxl_release_fence_buffer_objects(struct qxl_release *release)
@ drivers/gpu/drm/radeon/radeon_display.c:1826 @ int radeon_get_crtc_scanoutpos(struct drm_device *dev, unsigned int pipe,
 	struct radeon_device *rdev = dev->dev_private;
 
 	/* preempt_disable_rt() should go right here in PREEMPT_RT patchset. */
+	preempt_disable_rt();
 
 	/* Get optional system timestamp before query. */
 	if (stime)
@ drivers/gpu/drm/radeon/radeon_display.c:1919 @ int radeon_get_crtc_scanoutpos(struct drm_device *dev, unsigned int pipe,
 		*etime = ktime_get();
 
 	/* preempt_enable_rt() should go right here in PREEMPT_RT patchset. */
+	preempt_enable_rt();
 
 	/* Decode into vertical and horizontal scanout position. */
 	*vpos = position & 0x1fff;
@ drivers/gpu/drm/ttm/ttm_bo_util.c:184 @ static int ttm_copy_io_ttm_page(struct ttm_tt *ttm, void *src,
 		return -ENOMEM;
 
 	src = (void *)((unsigned long)src + (page << PAGE_SHIFT));
-	dst = kmap_atomic_prot(d, prot);
-	if (!dst)
-		return -ENOMEM;
+	/*
+	 * Ensure that a highmem page is mapped with the correct
+	 * pgprot. For non highmem the mapping is already there.
+	 */
+	dst = kmap_local_page_prot(d, prot);
 
 	memcpy_fromio(dst, src, PAGE_SIZE);
 
-	kunmap_atomic(dst);
+	kunmap_local(dst);
 
 	return 0;
 }
@ drivers/gpu/drm/ttm/ttm_bo_util.c:208 @ static int ttm_copy_ttm_io_page(struct ttm_tt *ttm, void *dst,
 		return -ENOMEM;
 
 	dst = (void *)((unsigned long)dst + (page << PAGE_SHIFT));
-	src = kmap_atomic_prot(s, prot);
-	if (!src)
-		return -ENOMEM;
+	/*
+	 * Ensure that a highmem page is mapped with the correct
+	 * pgprot. For non highmem the mapping is already there.
+	 */
+	src = kmap_local_page_prot(s, prot);
 
 	memcpy_toio(dst, src, PAGE_SIZE);
 
-	kunmap_atomic(src);
+	kunmap_local(src);
 
 	return 0;
 }
@ drivers/gpu/drm/vmwgfx/vmwgfx_blit.c:378 @ static int vmw_bo_cpu_blit_line(struct vmw_bo_blit_line_data *d,
 		copy_size = min_t(u32, copy_size, PAGE_SIZE - src_page_offset);
 
 		if (unmap_src) {
-			kunmap_atomic(d->src_addr);
+			kunmap_local(d->src_addr);
 			d->src_addr = NULL;
 		}
 
 		if (unmap_dst) {
-			kunmap_atomic(d->dst_addr);
+			kunmap_local(d->dst_addr);
 			d->dst_addr = NULL;
 		}
 
@ drivers/gpu/drm/vmwgfx/vmwgfx_blit.c:391 @ static int vmw_bo_cpu_blit_line(struct vmw_bo_blit_line_data *d,
 			if (WARN_ON_ONCE(dst_page >= d->dst_num_pages))
 				return -EINVAL;
 
-			d->dst_addr =
-				kmap_atomic_prot(d->dst_pages[dst_page],
-						 d->dst_prot);
-			if (!d->dst_addr)
-				return -ENOMEM;
-
+			d->dst_addr = kmap_local_page_prot(d->dst_pages[dst_page],
+							   d->dst_prot);
 			d->mapped_dst = dst_page;
 		}
 
@ drivers/gpu/drm/vmwgfx/vmwgfx_blit.c:400 @ static int vmw_bo_cpu_blit_line(struct vmw_bo_blit_line_data *d,
 			if (WARN_ON_ONCE(src_page >= d->src_num_pages))
 				return -EINVAL;
 
-			d->src_addr =
-				kmap_atomic_prot(d->src_pages[src_page],
-						 d->src_prot);
-			if (!d->src_addr)
-				return -ENOMEM;
-
+			d->src_addr = kmap_local_page_prot(d->src_pages[src_page],
+							   d->src_prot);
 			d->mapped_src = src_page;
 		}
 		diff->do_cpy(diff, d->dst_addr + dst_page_offset,
@ drivers/gpu/drm/vmwgfx/vmwgfx_blit.c:431 @ static int vmw_bo_cpu_blit_line(struct vmw_bo_blit_line_data *d,
  *
  * Performs a CPU blit from one buffer object to another avoiding a full
  * bo vmap which may exhaust- or fragment vmalloc space.
- * On supported architectures (x86), we're using kmap_atomic which avoids
- * cross-processor TLB- and cache flushes and may, on non-HIGHMEM systems
+ *
+ * On supported architectures (x86), we're using kmap_local_prot() which
+ * avoids cross-processor TLB- and cache flushes. kmap_local_prot() will
+ * either map a highmem page with the proper pgprot on HIGHMEM=y systems or
  * reference already set-up mappings.
  *
  * Neither of the buffer objects may be placed in PCI memory
@ drivers/gpu/drm/vmwgfx/vmwgfx_blit.c:497 @ int vmw_bo_cpu_blit(struct ttm_buffer_object *dst,
 	}
 out:
 	if (d.src_addr)
-		kunmap_atomic(d.src_addr);
+		kunmap_local(d.src_addr);
 	if (d.dst_addr)
-		kunmap_atomic(d.dst_addr);
+		kunmap_local(d.dst_addr);
 
 	return ret;
 }
@ drivers/hv/hyperv_vmbus.h:22 @
 #include <linux/atomic.h>
 #include <linux/hyperv.h>
 #include <linux/interrupt.h>
+#include <linux/irq.h>
 
 #include "hv_trace.h"
 
@ drivers/hv/vmbus_drv.c:25 @
 #include <linux/clockchips.h>
 #include <linux/cpu.h>
 #include <linux/sched/task_stack.h>
+#include <linux/irq.h>
 
 #include <linux/delay.h>
 #include <linux/notifier.h>
@ drivers/hv/vmbus_drv.c:1311 @ static void vmbus_isr(void)
 	void *page_addr = hv_cpu->synic_event_page;
 	struct hv_message *msg;
 	union hv_synic_event_flags *event;
+	struct pt_regs *regs = get_irq_regs();
+	u64 ip = regs ? instruction_pointer(regs) : 0;
 	bool handled = false;
 
 	if (unlikely(page_addr == NULL))
@ drivers/hv/vmbus_drv.c:1357 @ static void vmbus_isr(void)
 			tasklet_schedule(&hv_cpu->msg_dpc);
 	}
 
-	add_interrupt_randomness(hv_get_vector(), 0);
+	add_interrupt_randomness(hv_get_vector(), 0, ip);
 }
 
 /*
@ drivers/hv/vmbus_drv.c:1365 @ static void vmbus_isr(void)
  * buffer and call into Hyper-V to transfer the data.
  */
 static void hv_kmsg_dump(struct kmsg_dumper *dumper,
-			 enum kmsg_dump_reason reason)
+			 enum kmsg_dump_reason reason,
+			 struct kmsg_dumper_iter *iter)
 {
 	size_t bytes_written;
 	phys_addr_t panic_pa;
@ drivers/hv/vmbus_drv.c:1381 @ static void hv_kmsg_dump(struct kmsg_dumper *dumper,
 	 * Write dump contents to the page. No need to synchronize; panic should
 	 * be single-threaded.
 	 */
-	kmsg_dump_get_buffer(dumper, false, hv_panic_page, HV_HYP_PAGE_SIZE,
+	kmsg_dump_get_buffer(iter, false, hv_panic_page, HV_HYP_PAGE_SIZE,
 			     &bytes_written);
 	if (bytes_written)
 		hyperv_report_panic_msg(panic_pa, bytes_written);
@ drivers/leds/trigger/Kconfig:67 @ config LEDS_TRIGGER_BACKLIGHT
 
 config LEDS_TRIGGER_CPU
 	bool "LED CPU Trigger"
+	depends on !PREEMPT_RT
 	help
 	  This allows LEDs to be controlled by active CPUs. This shows
 	  the active CPUs across an array of LEDs so you can see which
@ drivers/md/raid5.c:2220 @ static void raid_run_ops(struct stripe_head *sh, unsigned long ops_request)
 	struct raid5_percpu *percpu;
 	unsigned long cpu;
 
-	cpu = get_cpu();
+	cpu = get_cpu_light();
 	percpu = per_cpu_ptr(conf->percpu, cpu);
+	spin_lock(&percpu->lock);
 	if (test_bit(STRIPE_OP_BIOFILL, &ops_request)) {
 		ops_run_biofill(sh);
 		overlap_clear++;
@ drivers/md/raid5.c:2281 @ static void raid_run_ops(struct stripe_head *sh, unsigned long ops_request)
 			if (test_and_clear_bit(R5_Overlap, &dev->flags))
 				wake_up(&sh->raid_conf->wait_for_overlap);
 		}
-	put_cpu();
+	spin_unlock(&percpu->lock);
+	put_cpu_light();
 }
 
 static void free_stripe(struct kmem_cache *sc, struct stripe_head *sh)
@ drivers/md/raid5.c:7104 @ static int raid456_cpu_up_prepare(unsigned int cpu, struct hlist_node *node)
 			__func__, cpu);
 		return -ENOMEM;
 	}
+	spin_lock_init(&per_cpu_ptr(conf->percpu, cpu)->lock);
 	return 0;
 }
 
@ drivers/md/raid5.h:638 @ struct r5conf {
 	int			recovery_disabled;
 	/* per cpu variables */
 	struct raid5_percpu {
+		spinlock_t	lock;		/* Protection for -RT */
 		struct page	*spare_page; /* Used when checking P/Q in raid6 */
 		void		*scribble;  /* space for constructing buffer
 					     * lists and performing address
@ drivers/mtd/mtdoops.c:270 @ static void find_next_position(struct mtdoops_context *cxt)
 }
 
 static void mtdoops_do_dump(struct kmsg_dumper *dumper,
-			    enum kmsg_dump_reason reason)
+			    enum kmsg_dump_reason reason,
+			    struct kmsg_dumper_iter *iter)
 {
 	struct mtdoops_context *cxt = container_of(dumper,
 			struct mtdoops_context, dump);
@ drivers/mtd/mtdoops.c:280 @ static void mtdoops_do_dump(struct kmsg_dumper *dumper,
 	if (reason == KMSG_DUMP_OOPS && !dump_oops)
 		return;
 
-	kmsg_dump_get_buffer(dumper, true, cxt->oops_buf + MTDOOPS_HEADER_SIZE,
+	kmsg_dump_get_buffer(iter, true, cxt->oops_buf + MTDOOPS_HEADER_SIZE,
 			     record_size - MTDOOPS_HEADER_SIZE, NULL);
 
 	if (reason != KMSG_DUMP_OOPS) {
@ drivers/net/arcnet/arc-rimi.c:335 @ static int __init arc_rimi_init(void)
 		dev->irq = 9;
 
 	if (arcrimi_probe(dev)) {
-		free_netdev(dev);
+		free_arcdev(dev);
 		return -EIO;
 	}
 
@ drivers/net/arcnet/arc-rimi.c:352 @ static void __exit arc_rimi_exit(void)
 	iounmap(lp->mem_start);
 	release_mem_region(dev->mem_start, dev->mem_end - dev->mem_start + 1);
 	free_irq(dev->irq, dev);
-	free_netdev(dev);
+	free_arcdev(dev);
 }
 
 #ifndef MODULE
@ drivers/net/arcnet/arcdevice.h:301 @ struct arcnet_local {
 
 	int excnak_pending;    /* We just got an excesive nak interrupt */
 
+	/* RESET flag handling */
+	int reset_in_progress;
+	struct work_struct reset_work;
+
 	struct {
 		uint16_t sequence;	/* sequence number (incs with each packet) */
 		__be16 aborted_seq;
@ drivers/net/arcnet/arcdevice.h:357 @ void arcnet_dump_skb(struct net_device *dev, struct sk_buff *skb, char *desc)
 
 void arcnet_unregister_proto(struct ArcProto *proto);
 irqreturn_t arcnet_interrupt(int irq, void *dev_id);
+
 struct net_device *alloc_arcdev(const char *name);
+void free_arcdev(struct net_device *dev);
 
 int arcnet_open(struct net_device *dev);
 int arcnet_close(struct net_device *dev);
@ drivers/net/arcnet/arcnet.c:390 @ static void arcnet_timer(struct timer_list *t)
 	struct arcnet_local *lp = from_timer(lp, t, timer);
 	struct net_device *dev = lp->dev;
 
-	if (!netif_carrier_ok(dev)) {
+	spin_lock_irq(&lp->lock);
+
+	if (!lp->reset_in_progress && !netif_carrier_ok(dev)) {
 		netif_carrier_on(dev);
 		netdev_info(dev, "link up\n");
 	}
+
+	spin_unlock_irq(&lp->lock);
+}
+
+static void reset_device_work(struct work_struct *work)
+{
+	struct arcnet_local *lp;
+	struct net_device *dev;
+
+	lp = container_of(work, struct arcnet_local, reset_work);
+	dev = lp->dev;
+
+	/* Do not bring the network interface back up if an ifdown
+	 * was already done.
+	 */
+	if (!netif_running(dev) || !lp->reset_in_progress)
+		return;
+
+	rtnl_lock();
+
+	/* Do another check, in case of an ifdown that was triggered in
+	 * the small race window between the exit condition above and
+	 * acquiring RTNL.
+	 */
+	if (!netif_running(dev) || !lp->reset_in_progress)
+		goto out;
+
+	dev_close(dev);
+	dev_open(dev, NULL);
+
+out:
+	rtnl_unlock();
 }
 
 static void arcnet_reply_tasklet(unsigned long data)
@ drivers/net/arcnet/arcnet.c:489 @ struct net_device *alloc_arcdev(const char *name)
 		lp->dev = dev;
 		spin_lock_init(&lp->lock);
 		timer_setup(&lp->timer, arcnet_timer, 0);
+		INIT_WORK(&lp->reset_work, reset_device_work);
 	}
 
 	return dev;
 }
 EXPORT_SYMBOL(alloc_arcdev);
 
+void free_arcdev(struct net_device *dev)
+{
+	struct arcnet_local *lp = netdev_priv(dev);
+
+	/* Do not cancel this at ->ndo_close(), as the workqueue itself
+	 * indirectly calls the ifdown path through dev_close().
+	 */
+	cancel_work_sync(&lp->reset_work);
+	free_netdev(dev);
+}
+EXPORT_SYMBOL(free_arcdev);
+
 /* Open/initialize the board.  This is called sometime after booting when
  * the 'ifconfig' program is run.
  *
@ drivers/net/arcnet/arcnet.c:637 @ int arcnet_close(struct net_device *dev)
 
 	/* shut down the card */
 	lp->hw.close(dev);
+
+	/* reset counters */
+	lp->reset_in_progress = 0;
+
 	module_put(lp->hw.owner);
 	return 0;
 }
@ drivers/net/arcnet/arcnet.c:874 @ irqreturn_t arcnet_interrupt(int irq, void *dev_id)
 
 	spin_lock_irqsave(&lp->lock, flags);
 
+	if (lp->reset_in_progress)
+		goto out;
+
 	/* RESET flag was enabled - if device is not running, we must
 	 * clear it right away (but nothing else).
 	 */
@ drivers/net/arcnet/arcnet.c:909 @ irqreturn_t arcnet_interrupt(int irq, void *dev_id)
 		if (status & RESETflag) {
 			arc_printk(D_NORMAL, dev, "spurious reset (status=%Xh)\n",
 				   status);
-			arcnet_close(dev);
-			arcnet_open(dev);
+
+			lp->reset_in_progress = 1;
+			netif_stop_queue(dev);
+			netif_carrier_off(dev);
+			schedule_work(&lp->reset_work);
 
 			/* get out of the interrupt handler! */
-			break;
+			goto out;
 		}
 		/* RX is inhibited - we must have received something.
 		 * Prepare to receive into the next buffer.
@ drivers/net/arcnet/arcnet.c:1112 @ irqreturn_t arcnet_interrupt(int irq, void *dev_id)
 	udelay(1);
 	lp->hw.intmask(dev, lp->intmask);
 
+out:
 	spin_unlock_irqrestore(&lp->lock, flags);
 	return retval;
 }
@ drivers/net/arcnet/com20020-isa.c:172 @ static int __init com20020_init(void)
 		dev->irq = 9;
 
 	if (com20020isa_probe(dev)) {
-		free_netdev(dev);
+		free_arcdev(dev);
 		return -EIO;
 	}
 
@ drivers/net/arcnet/com20020-isa.c:185 @ static void __exit com20020_exit(void)
 	unregister_netdev(my_dev);
 	free_irq(my_dev->irq, my_dev);
 	release_region(my_dev->base_addr, ARCNET_TOTAL_SIZE);
-	free_netdev(my_dev);
+	free_arcdev(my_dev);
 }
 
 #ifndef MODULE
@ drivers/net/arcnet/com20020-pci.c:294 @ static void com20020pci_remove(struct pci_dev *pdev)
 
 		unregister_netdev(dev);
 		free_irq(dev->irq, dev);
-		free_netdev(dev);
+		free_arcdev(dev);
 	}
 }
 
@ drivers/net/arcnet/com20020_cs.c:180 @ static void com20020_detach(struct pcmcia_device *link)
 		dev = info->dev;
 		if (dev) {
 			dev_dbg(&link->dev, "kfree...\n");
-			free_netdev(dev);
+			free_arcdev(dev);
 		}
 		dev_dbg(&link->dev, "kfree2...\n");
 		kfree(info);
@ drivers/net/arcnet/com90io.c:399 @ static int __init com90io_init(void)
 	err = com90io_probe(dev);
 
 	if (err) {
-		free_netdev(dev);
+		free_arcdev(dev);
 		return err;
 	}
 
@ drivers/net/arcnet/com90io.c:422 @ static void __exit com90io_exit(void)
 
 	free_irq(dev->irq, dev);
 	release_region(dev->base_addr, ARCNET_TOTAL_SIZE);
-	free_netdev(dev);
+	free_arcdev(dev);
 }
 
 module_init(com90io_init)
@ drivers/net/arcnet/com90xx.c:557 @ static int __init com90xx_found(int ioaddr, int airq, u_long shmem,
 err_release_mem:
 	release_mem_region(dev->mem_start, dev->mem_end - dev->mem_start + 1);
 err_free_dev:
-	free_netdev(dev);
+	free_arcdev(dev);
 	return -EIO;
 }
 
@ drivers/net/arcnet/com90xx.c:675 @ static void __exit com90xx_exit(void)
 		release_region(dev->base_addr, ARCNET_TOTAL_SIZE);
 		release_mem_region(dev->mem_start,
 				   dev->mem_end - dev->mem_start + 1);
-		free_netdev(dev);
+		free_arcdev(dev);
 	}
 }
 
@ drivers/net/ethernet/chelsio/cxgb/common.h:241 @ struct adapter {
 	int msg_enable;
 	u32 mmio_len;
 
-	struct work_struct ext_intr_handler_task;
 	struct adapter_params params;
 
 	/* Terminator modules. */
@ drivers/net/ethernet/chelsio/cxgb/common.h:259 @ struct adapter {
 
 	/* guards async operations */
 	spinlock_t async_lock ____cacheline_aligned;
+	u32 pending_thread_intr;
 	u32 slow_intr_mask;
 	int t1powersave;
 };
@ drivers/net/ethernet/chelsio/cxgb/common.h:337 @ void t1_interrupts_enable(adapter_t *adapter);
 void t1_interrupts_disable(adapter_t *adapter);
 void t1_interrupts_clear(adapter_t *adapter);
 int t1_elmer0_ext_intr_handler(adapter_t *adapter);
-void t1_elmer0_ext_intr(adapter_t *adapter);
-int t1_slow_intr_handler(adapter_t *adapter);
+irqreturn_t t1_slow_intr_handler(adapter_t *adapter);
 
 int t1_link_start(struct cphy *phy, struct cmac *mac, struct link_config *lc);
 const struct board_info *t1_get_board_info(unsigned int board_id);
@ drivers/net/ethernet/chelsio/cxgb/common.h:349 @ int t1_get_board_rev(adapter_t *adapter, const struct board_info *bi,
 int t1_init_hw_modules(adapter_t *adapter);
 int t1_init_sw_modules(adapter_t *adapter, const struct board_info *bi);
 void t1_free_sw_modules(adapter_t *adapter);
-void t1_fatal_err(adapter_t *adapter);
 void t1_link_changed(adapter_t *adapter, int port_id);
 void t1_link_negotiated(adapter_t *adapter, int port_id, int link_stat,
 			    int speed, int duplex, int pause);
@ drivers/net/ethernet/chelsio/cxgb/cxgb2.c:214 @ static int cxgb_up(struct adapter *adapter)
 	t1_interrupts_clear(adapter);
 
 	adapter->params.has_msi = !disable_msi && !pci_enable_msi(adapter->pdev);
-	err = request_irq(adapter->pdev->irq, t1_interrupt,
-			  adapter->params.has_msi ? 0 : IRQF_SHARED,
-			  adapter->name, adapter);
+	err = request_threaded_irq(adapter->pdev->irq, t1_interrupt,
+				   t1_interrupt_thread,
+				   adapter->params.has_msi ? 0 : IRQF_SHARED,
+				   adapter->name, adapter);
 	if (err) {
 		if (adapter->params.has_msi)
 			pci_disable_msi(adapter->pdev);
@ drivers/net/ethernet/chelsio/cxgb/cxgb2.c:920 @ static void mac_stats_task(struct work_struct *work)
 	spin_unlock(&adapter->work_lock);
 }
 
-/*
- * Processes elmer0 external interrupts in process context.
- */
-static void ext_intr_task(struct work_struct *work)
-{
-	struct adapter *adapter =
-		container_of(work, struct adapter, ext_intr_handler_task);
-
-	t1_elmer0_ext_intr_handler(adapter);
-
-	/* Now reenable external interrupts */
-	spin_lock_irq(&adapter->async_lock);
-	adapter->slow_intr_mask |= F_PL_INTR_EXT;
-	writel(F_PL_INTR_EXT, adapter->regs + A_PL_CAUSE);
-	writel(adapter->slow_intr_mask | F_PL_INTR_SGE_DATA,
-		   adapter->regs + A_PL_ENABLE);
-	spin_unlock_irq(&adapter->async_lock);
-}
-
-/*
- * Interrupt-context handler for elmer0 external interrupts.
- */
-void t1_elmer0_ext_intr(struct adapter *adapter)
-{
-	/*
-	 * Schedule a task to handle external interrupts as we require
-	 * a process context.  We disable EXT interrupts in the interim
-	 * and let the task reenable them when it's done.
-	 */
-	adapter->slow_intr_mask &= ~F_PL_INTR_EXT;
-	writel(adapter->slow_intr_mask | F_PL_INTR_SGE_DATA,
-		   adapter->regs + A_PL_ENABLE);
-	schedule_work(&adapter->ext_intr_handler_task);
-}
-
-void t1_fatal_err(struct adapter *adapter)
-{
-	if (adapter->flags & FULL_INIT_DONE) {
-		t1_sge_stop(adapter->sge);
-		t1_interrupts_disable(adapter);
-	}
-	pr_alert("%s: encountered fatal error, operation suspended\n",
-		 adapter->name);
-}
-
 static const struct net_device_ops cxgb_netdev_ops = {
 	.ndo_open		= cxgb_open,
 	.ndo_stop		= cxgb_close,
@ drivers/net/ethernet/chelsio/cxgb/cxgb2.c:1021 @ static int init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 			spin_lock_init(&adapter->async_lock);
 			spin_lock_init(&adapter->mac_lock);
 
-			INIT_WORK(&adapter->ext_intr_handler_task,
-				  ext_intr_task);
 			INIT_DELAYED_WORK(&adapter->stats_update_task,
 					  mac_stats_task);
 
@ drivers/net/ethernet/chelsio/cxgb/sge.c:943 @ void t1_sge_intr_clear(struct sge *sge)
 /*
  * SGE 'Error' interrupt handler
  */
-int t1_sge_intr_error_handler(struct sge *sge)
+bool t1_sge_intr_error_handler(struct sge *sge)
 {
 	struct adapter *adapter = sge->adapter;
 	u32 cause = readl(adapter->regs + A_SG_INT_CAUSE);
+	bool wake = false;
 
 	if (adapter->port[0].dev->hw_features & NETIF_F_TSO)
 		cause &= ~F_PACKET_TOO_BIG;
@ drivers/net/ethernet/chelsio/cxgb/sge.c:971 @ int t1_sge_intr_error_handler(struct sge *sge)
 		sge->stats.pkt_mismatch++;
 		pr_alert("%s: SGE packet mismatch\n", adapter->name);
 	}
-	if (cause & SGE_INT_FATAL)
-		t1_fatal_err(adapter);
+	if (cause & SGE_INT_FATAL) {
+		t1_interrupts_disable(adapter);
+		adapter->pending_thread_intr |= F_PL_INTR_SGE_ERR;
+		wake = true;
+	}
 
 	writel(cause, adapter->regs + A_SG_INT_CAUSE);
-	return 0;
+	return wake;
 }
 
 const struct sge_intr_counts *t1_sge_get_intr_counts(const struct sge *sge)
@ drivers/net/ethernet/chelsio/cxgb/sge.c:1626 @ int t1_poll(struct napi_struct *napi, int budget)
 	return work_done;
 }
 
+irqreturn_t t1_interrupt_thread(int irq, void *data)
+{
+	struct adapter *adapter = data;
+	u32 pending_thread_intr;
+
+	spin_lock_irq(&adapter->async_lock);
+	pending_thread_intr = adapter->pending_thread_intr;
+	adapter->pending_thread_intr = 0;
+	spin_unlock_irq(&adapter->async_lock);
+
+	if (!pending_thread_intr)
+		return IRQ_NONE;
+
+	if (pending_thread_intr & F_PL_INTR_EXT)
+		t1_elmer0_ext_intr_handler(adapter);
+
+	/* This error is fatal, interrupts remain off */
+	if (pending_thread_intr & F_PL_INTR_SGE_ERR) {
+		pr_alert("%s: encountered fatal error, operation suspended\n",
+			 adapter->name);
+		t1_sge_stop(adapter->sge);
+		return IRQ_HANDLED;
+	}
+
+	spin_lock_irq(&adapter->async_lock);
+	adapter->slow_intr_mask |= F_PL_INTR_EXT;
+
+	writel(F_PL_INTR_EXT, adapter->regs + A_PL_CAUSE);
+	writel(adapter->slow_intr_mask | F_PL_INTR_SGE_DATA,
+	       adapter->regs + A_PL_ENABLE);
+	spin_unlock_irq(&adapter->async_lock);
+
+	return IRQ_HANDLED;
+}
+
 irqreturn_t t1_interrupt(int irq, void *data)
 {
 	struct adapter *adapter = data;
 	struct sge *sge = adapter->sge;
-	int handled;
+	irqreturn_t handled;
 
 	if (likely(responses_pending(adapter))) {
 		writel(F_PL_INTR_SGE_DATA, adapter->regs + A_PL_CAUSE);
@ drivers/net/ethernet/chelsio/cxgb/sge.c:1687 @ irqreturn_t t1_interrupt(int irq, void *data)
 	handled = t1_slow_intr_handler(adapter);
 	spin_unlock(&adapter->async_lock);
 
-	if (!handled)
+	if (handled == IRQ_NONE)
 		sge->stats.unhandled_irqs++;
 
-	return IRQ_RETVAL(handled != 0);
+	return handled;
 }
 
 /*
@ drivers/net/ethernet/chelsio/cxgb/sge.h:77 @ struct sge *t1_sge_create(struct adapter *, struct sge_params *);
 int t1_sge_configure(struct sge *, struct sge_params *);
 int t1_sge_set_coalesce_params(struct sge *, struct sge_params *);
 void t1_sge_destroy(struct sge *);
+irqreturn_t t1_interrupt_thread(int irq, void *data);
 irqreturn_t t1_interrupt(int irq, void *cookie);
 int t1_poll(struct napi_struct *, int);
 
@ drivers/net/ethernet/chelsio/cxgb/sge.h:85 @ netdev_tx_t t1_start_xmit(struct sk_buff *skb, struct net_device *dev);
 void t1_vlan_mode(struct adapter *adapter, netdev_features_t features);
 void t1_sge_start(struct sge *);
 void t1_sge_stop(struct sge *);
-int t1_sge_intr_error_handler(struct sge *);
+bool t1_sge_intr_error_handler(struct sge *sge);
 void t1_sge_intr_enable(struct sge *);
 void t1_sge_intr_disable(struct sge *);
 void t1_sge_intr_clear(struct sge *);
@ drivers/net/ethernet/chelsio/cxgb/subr.c:173 @ void t1_link_changed(adapter_t *adapter, int port_id)
 	t1_link_negotiated(adapter, port_id, link_ok, speed, duplex, fc);
 }
 
-static int t1_pci_intr_handler(adapter_t *adapter)
+static bool t1_pci_intr_handler(adapter_t *adapter)
 {
 	u32 pcix_cause;
 
@ drivers/net/ethernet/chelsio/cxgb/subr.c:182 @ static int t1_pci_intr_handler(adapter_t *adapter)
 	if (pcix_cause) {
 		pci_write_config_dword(adapter->pdev, A_PCICFG_INTR_CAUSE,
 				       pcix_cause);
-		t1_fatal_err(adapter);    /* PCI errors are fatal */
+		/* PCI errors are fatal */
+		t1_interrupts_disable(adapter);
+		adapter->pending_thread_intr |= F_PL_INTR_SGE_ERR;
+		pr_alert("%s: PCI error encountered.\n", adapter->name);
+		return true;
 	}
-	return 0;
+	return false;
 }
 
 #ifdef CONFIG_CHELSIO_T1_1G
@ drivers/net/ethernet/chelsio/cxgb/subr.c:217 @ static int fpga_phy_intr_handler(adapter_t *adapter)
 /*
  * Slow path interrupt handler for FPGAs.
  */
-static int fpga_slow_intr(adapter_t *adapter)
+static irqreturn_t fpga_slow_intr(adapter_t *adapter)
 {
 	u32 cause = readl(adapter->regs + A_PL_CAUSE);
+	irqreturn_t ret = IRQ_NONE;
 
 	cause &= ~F_PL_INTR_SGE_DATA;
-	if (cause & F_PL_INTR_SGE_ERR)
-		t1_sge_intr_error_handler(adapter->sge);
+	if (cause & F_PL_INTR_SGE_ERR) {
+		if (t1_sge_intr_error_handler(adapter->sge))
+			ret = IRQ_WAKE_THREAD;
+	}
 
 	if (cause & FPGA_PCIX_INTERRUPT_GMAC)
 		fpga_phy_intr_handler(adapter);
@ drivers/net/ethernet/chelsio/cxgb/subr.c:241 @ static int fpga_slow_intr(adapter_t *adapter)
 		/* Clear TP interrupt */
 		writel(tp_cause, adapter->regs + FPGA_TP_ADDR_INTERRUPT_CAUSE);
 	}
-	if (cause & FPGA_PCIX_INTERRUPT_PCIX)
-		t1_pci_intr_handler(adapter);
+	if (cause & FPGA_PCIX_INTERRUPT_PCIX) {
+		if (t1_pci_intr_handler(adapter))
+			ret = IRQ_WAKE_THREAD;
+	}
 
 	/* Clear the interrupts just processed. */
 	if (cause)
 		writel(cause, adapter->regs + A_PL_CAUSE);
 
-	return cause != 0;
+	if (ret != IRQ_NONE)
+		return ret;
+
+	return cause == 0 ? IRQ_NONE : IRQ_HANDLED;
 }
 #endif
 
@ drivers/net/ethernet/chelsio/cxgb/subr.c:857 @ void t1_interrupts_clear(adapter_t* adapter)
 /*
  * Slow path interrupt handler for ASICs.
  */
-static int asic_slow_intr(adapter_t *adapter)
+static irqreturn_t asic_slow_intr(adapter_t *adapter)
 {
 	u32 cause = readl(adapter->regs + A_PL_CAUSE);
+	irqreturn_t ret = IRQ_HANDLED;
 
 	cause &= adapter->slow_intr_mask;
 	if (!cause)
-		return 0;
-	if (cause & F_PL_INTR_SGE_ERR)
-		t1_sge_intr_error_handler(adapter->sge);
+		return IRQ_NONE;
+	if (cause & F_PL_INTR_SGE_ERR) {
+		if (t1_sge_intr_error_handler(adapter->sge))
+			ret = IRQ_WAKE_THREAD;
+	}
 	if (cause & F_PL_INTR_TP)
 		t1_tp_intr_handler(adapter->tp);
 	if (cause & F_PL_INTR_ESPI)
 		t1_espi_intr_handler(adapter->espi);
-	if (cause & F_PL_INTR_PCIX)
-		t1_pci_intr_handler(adapter);
-	if (cause & F_PL_INTR_EXT)
-		t1_elmer0_ext_intr(adapter);
+	if (cause & F_PL_INTR_PCIX) {
+		if (t1_pci_intr_handler(adapter))
+			ret = IRQ_WAKE_THREAD;
+	}
+	if (cause & F_PL_INTR_EXT) {
+		/* Wake the threaded interrupt to handle external interrupts as
+		 * we require a process context. We disable EXT interrupts in
+		 * the interim and let the thread reenable them when it's done.
+		 */
+		adapter->pending_thread_intr |= F_PL_INTR_EXT;
+		adapter->slow_intr_mask &= ~F_PL_INTR_EXT;
+		writel(adapter->slow_intr_mask | F_PL_INTR_SGE_DATA,
+		       adapter->regs + A_PL_ENABLE);
+		ret = IRQ_WAKE_THREAD;
+	}
 
 	/* Clear the interrupts just processed. */
 	writel(cause, adapter->regs + A_PL_CAUSE);
 	readl(adapter->regs + A_PL_CAUSE); /* flush writes */
-	return 1;
+	return ret;
 }
 
-int t1_slow_intr_handler(adapter_t *adapter)
+irqreturn_t t1_slow_intr_handler(adapter_t *adapter)
 {
 #ifdef CONFIG_CHELSIO_T1_1G
 	if (!t1_is_asic(adapter))
@ drivers/net/ethernet/dlink/sundance.c:966 @ static void tx_timeout(struct net_device *dev, unsigned int txqueue)
 	unsigned long flag;
 
 	netif_stop_queue(dev);
-	tasklet_disable(&np->tx_tasklet);
+	tasklet_disable_in_atomic(&np->tx_tasklet);
 	iowrite16(0, ioaddr + IntrEnable);
 	printk(KERN_WARNING "%s: Transmit timed out, TxStatus %2.2x "
 		   "TxFrameId %2.2x,"
@ drivers/net/ethernet/jme.c:1268 @ jme_stop_shutdown_timer(struct jme_adapter *jme)
 	jwrite32f(jme, JME_APMC, apmc);
 }
 
-static void jme_link_change_tasklet(struct tasklet_struct *t)
+static void jme_link_change_work(struct work_struct *work)
 {
-	struct jme_adapter *jme = from_tasklet(jme, t, linkch_task);
+	struct jme_adapter *jme = container_of(work, struct jme_adapter, linkch_task);
 	struct net_device *netdev = jme->dev;
 	int rc;
 
@ drivers/net/ethernet/jme.c:1513 @ jme_intr_msi(struct jme_adapter *jme, u32 intrstat)
 		 * all other events are ignored
 		 */
 		jwrite32(jme, JME_IEVE, intrstat);
-		tasklet_schedule(&jme->linkch_task);
+		schedule_work(&jme->linkch_task);
 		goto out_reenable;
 	}
 
@ drivers/net/ethernet/jme.c:1835 @ jme_open(struct net_device *netdev)
 	jme_clear_pm_disable_wol(jme);
 	JME_NAPI_ENABLE(jme);
 
-	tasklet_setup(&jme->linkch_task, jme_link_change_tasklet);
 	tasklet_setup(&jme->txclean_task, jme_tx_clean_tasklet);
 	tasklet_setup(&jme->rxclean_task, jme_rx_clean_tasklet);
 	tasklet_setup(&jme->rxempty_task, jme_rx_empty_tasklet);
@ drivers/net/ethernet/jme.c:1922 @ jme_close(struct net_device *netdev)
 
 	JME_NAPI_DISABLE(jme);
 
-	tasklet_kill(&jme->linkch_task);
+	cancel_work_sync(&jme->linkch_task);
 	tasklet_kill(&jme->txclean_task);
 	tasklet_kill(&jme->rxclean_task);
 	tasklet_kill(&jme->rxempty_task);
@ drivers/net/ethernet/jme.c:3037 @ jme_init_one(struct pci_dev *pdev,
 	atomic_set(&jme->rx_empty, 1);
 
 	tasklet_setup(&jme->pcc_task, jme_pcc_tasklet);
+	INIT_WORK(&jme->linkch_task, jme_link_change_work);
 	jme->dpi.cur = PCC_P1;
 
 	jme->reg_ghc = 0;
@ drivers/net/ethernet/jme.h:414 @ struct jme_adapter {
 	struct tasklet_struct	rxempty_task;
 	struct tasklet_struct	rxclean_task;
 	struct tasklet_struct	txclean_task;
-	struct tasklet_struct	linkch_task;
+	struct work_struct	linkch_task;
 	struct tasklet_struct	pcc_task;
 	unsigned long		flags;
 	u32			reg_txcs;
@ drivers/net/wireless/ath/ath9k/beacon.c:254 @ void ath9k_beacon_ensure_primary_slot(struct ath_softc *sc)
 	int first_slot = ATH_BCBUF;
 	int slot;
 
-	tasklet_disable(&sc->bcon_tasklet);
+	tasklet_disable_in_atomic(&sc->bcon_tasklet);
 
 	/* Find first taken slot. */
 	for (slot = 0; slot < ATH_BCBUF; slot++) {
@ drivers/pci/controller/pci-hyperv.c:1460 @ static void hv_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
 	 * Prevents hv_pci_onchannelcallback() from running concurrently
 	 * in the tasklet.
 	 */
-	tasklet_disable(&channel->callback_event);
+	tasklet_disable_in_atomic(&channel->callback_event);
 
 	/*
 	 * Since this function is called with IRQ locks held, can't
@ drivers/scsi/fcoe/fcoe.c:1455 @ static int fcoe_rcv(struct sk_buff *skb, struct net_device *netdev,
 static int fcoe_alloc_paged_crc_eof(struct sk_buff *skb, int tlen)
 {
 	struct fcoe_percpu_s *fps;
-	int rc;
+	int rc, cpu = get_cpu_light();
 
-	fps = &get_cpu_var(fcoe_percpu);
+	fps = &per_cpu(fcoe_percpu, cpu);
 	rc = fcoe_get_paged_crc_eof(skb, tlen, fps);
-	put_cpu_var(fcoe_percpu);
+	put_cpu_light();
 
 	return rc;
 }
@ drivers/scsi/fcoe/fcoe.c:1644 @ static inline int fcoe_filter_frames(struct fc_lport *lport,
 		return 0;
 	}
 
-	stats = per_cpu_ptr(lport->stats, get_cpu());
+	stats = per_cpu_ptr(lport->stats, get_cpu_light());
 	stats->InvalidCRCCount++;
 	if (stats->InvalidCRCCount < 5)
 		printk(KERN_WARNING "fcoe: dropping frame with CRC error\n");
-	put_cpu();
+	put_cpu_light();
 	return -EINVAL;
 }
 
@ drivers/scsi/fcoe/fcoe.c:1689 @ static void fcoe_recv_frame(struct sk_buff *skb)
 	 */
 	hp = (struct fcoe_hdr *) skb_network_header(skb);
 
-	stats = per_cpu_ptr(lport->stats, get_cpu());
+	stats = per_cpu_ptr(lport->stats, get_cpu_light());
 	if (unlikely(FC_FCOE_DECAPS_VER(hp) != FC_FCOE_VER)) {
 		if (stats->ErrorFrames < 5)
 			printk(KERN_WARNING "fcoe: FCoE version "
@ drivers/scsi/fcoe/fcoe.c:1721 @ static void fcoe_recv_frame(struct sk_buff *skb)
 		goto drop;
 
 	if (!fcoe_filter_frames(lport, fp)) {
-		put_cpu();
+		put_cpu_light();
 		fc_exch_recv(lport, fp);
 		return;
 	}
 drop:
 	stats->ErrorFrames++;
-	put_cpu();
+	put_cpu_light();
 	kfree_skb(skb);
 }
 
@ drivers/scsi/fcoe/fcoe_ctlr.c:831 @ static unsigned long fcoe_ctlr_age_fcfs(struct fcoe_ctlr *fip)
 
 	INIT_LIST_HEAD(&del_list);
 
-	stats = per_cpu_ptr(fip->lp->stats, get_cpu());
+	stats = per_cpu_ptr(fip->lp->stats, get_cpu_light());
 
 	list_for_each_entry_safe(fcf, next, &fip->fcfs, list) {
 		deadline = fcf->time + fcf->fka_period + fcf->fka_period / 2;
@ drivers/scsi/fcoe/fcoe_ctlr.c:867 @ static unsigned long fcoe_ctlr_age_fcfs(struct fcoe_ctlr *fip)
 				sel_time = fcf->time;
 		}
 	}
-	put_cpu();
+	put_cpu_light();
 
 	list_for_each_entry_safe(fcf, next, &del_list, list) {
 		/* Removes fcf from current list */
@ drivers/scsi/libfc/fc_exch.c:829 @ static struct fc_exch *fc_exch_em_alloc(struct fc_lport *lport,
 	}
 	memset(ep, 0, sizeof(*ep));
 
-	cpu = get_cpu();
+	cpu = get_cpu_light();
 	pool = per_cpu_ptr(mp->pool, cpu);
 	spin_lock_bh(&pool->lock);
-	put_cpu();
+	put_cpu_light();
 
 	/* peek cache of free slot */
 	if (pool->left != FC_XID_UNKNOWN) {
@ drivers/tty/serial/8250/8250.h:134 @ static inline void serial_dl_write(struct uart_8250_port *up, int value)
 	up->dl_write(up, value);
 }
 
+static inline void serial8250_set_IER(struct uart_8250_port *up,
+				      unsigned char ier)
+{
+	struct uart_port *port = &up->port;
+	unsigned int flags;
+	bool is_console;
+
+	is_console = uart_console(port);
+
+	if (is_console)
+		console_atomic_lock(&flags);
+
+	serial_out(up, UART_IER, ier);
+
+	if (is_console)
+		console_atomic_unlock(flags);
+}
+
+static inline unsigned char serial8250_clear_IER(struct uart_8250_port *up)
+{
+	struct uart_port *port = &up->port;
+	unsigned int clearval = 0;
+	unsigned int prior;
+	unsigned int flags;
+	bool is_console;
+
+	is_console = uart_console(port);
+
+	if (up->capabilities & UART_CAP_UUE)
+		clearval = UART_IER_UUE;
+
+	if (is_console)
+		console_atomic_lock(&flags);
+
+	prior = serial_port_in(port, UART_IER);
+	serial_port_out(port, UART_IER, clearval);
+
+	if (is_console)
+		console_atomic_unlock(flags);
+
+	return prior;
+}
+
 static inline bool serial8250_set_THRI(struct uart_8250_port *up)
 {
 	if (up->ier & UART_IER_THRI)
 		return false;
 	up->ier |= UART_IER_THRI;
-	serial_out(up, UART_IER, up->ier);
+	serial8250_set_IER(up, up->ier);
 	return true;
 }
 
@ drivers/tty/serial/8250/8250.h:191 @ static inline bool serial8250_clear_THRI(struct uart_8250_port *up)
 	if (!(up->ier & UART_IER_THRI))
 		return false;
 	up->ier &= ~UART_IER_THRI;
-	serial_out(up, UART_IER, up->ier);
+	serial8250_set_IER(up, up->ier);
 	return true;
 }
 
@ drivers/tty/serial/8250/8250_core.c:277 @ static void serial8250_backup_timeout(struct timer_list *t)
 	 * Must disable interrupts or else we risk racing with the interrupt
 	 * based handler.
 	 */
-	if (up->port.irq) {
-		ier = serial_in(up, UART_IER);
-		serial_out(up, UART_IER, 0);
-	}
+	if (up->port.irq)
+		ier = serial8250_clear_IER(up);
 
 	iir = serial_in(up, UART_IIR);
 
@ drivers/tty/serial/8250/8250_core.c:301 @ static void serial8250_backup_timeout(struct timer_list *t)
 		serial8250_tx_chars(up);
 
 	if (up->port.irq)
-		serial_out(up, UART_IER, ier);
+		serial8250_set_IER(up, ier);
 
 	spin_unlock_irqrestore(&up->port.lock, flags);
 
@ drivers/tty/serial/8250/8250_core.c:579 @ serial8250_register_ports(struct uart_driver *drv, struct device *dev)
 
 #ifdef CONFIG_SERIAL_8250_CONSOLE
 
+static void univ8250_console_write_atomic(struct console *co, const char *s,
+					  unsigned int count)
+{
+	struct uart_8250_port *up = &serial8250_ports[co->index];
+
+	serial8250_console_write_atomic(up, s, count);
+}
+
 static void univ8250_console_write(struct console *co, const char *s,
 				   unsigned int count)
 {
@ drivers/tty/serial/8250/8250_core.c:680 @ static int univ8250_console_match(struct console *co, char *name, int idx,
 
 static struct console univ8250_console = {
 	.name		= "ttyS",
+	.write_atomic	= univ8250_console_write_atomic,
 	.write		= univ8250_console_write,
 	.device		= uart_console_device,
 	.setup		= univ8250_console_setup,
@ drivers/tty/serial/8250/8250_fsl.c:63 @ int fsl8250_handle_irq(struct uart_port *port)
 
 	/* Stop processing interrupts on input overrun */
 	if ((orig_lsr & UART_LSR_OE) && (up->overrun_backoff_time_ms > 0)) {
+		unsigned int ca_flags;
 		unsigned long delay;
+		bool is_console;
 
+		is_console = uart_console(port);
+
+		if (is_console)
+			console_atomic_lock(&ca_flags);
 		up->ier = port->serial_in(port, UART_IER);
+		if (is_console)
+			console_atomic_unlock(ca_flags);
+
 		if (up->ier & (UART_IER_RLSI | UART_IER_RDI)) {
 			port->ops->stop_rx(port);
 		} else {
@ drivers/tty/serial/8250/8250_ingenic.c:149 @ OF_EARLYCON_DECLARE(x1000_uart, "ingenic,x1000-uart",
 
 static void ingenic_uart_serial_out(struct uart_port *p, int offset, int value)
 {
+	unsigned int flags;
+	bool is_console;
 	int ier;
 
 	switch (offset) {
@ drivers/tty/serial/8250/8250_ingenic.c:172 @ static void ingenic_uart_serial_out(struct uart_port *p, int offset, int value)
 		 * If we have enabled modem status IRQs we should enable
 		 * modem mode.
 		 */
+		is_console = uart_console(p);
+		if (is_console)
+			console_atomic_lock(&flags);
 		ier = p->serial_in(p, UART_IER);
+		if (is_console)
+			console_atomic_unlock(flags);
 
 		if (ier & UART_IER_MSI)
 			value |= UART_MCR_MDCE | UART_MCR_FCM;
@ drivers/tty/serial/8250/8250_mtk.c:221 @ static void mtk8250_shutdown(struct uart_port *port)
 
 static void mtk8250_disable_intrs(struct uart_8250_port *up, int mask)
 {
-	serial_out(up, UART_IER, serial_in(up, UART_IER) & (~mask));
+	struct uart_port *port = &up->port;
+	unsigned int flags;
+	unsigned int ier;
+	bool is_console;
+
+	is_console = uart_console(port);
+
+	if (is_console)
+		console_atomic_lock(&flags);
+
+	ier = serial_in(up, UART_IER);
+	serial_out(up, UART_IER, ier & (~mask));
+
+	if (is_console)
+		console_atomic_unlock(flags);
 }
 
 static void mtk8250_enable_intrs(struct uart_8250_port *up, int mask)
 {
-	serial_out(up, UART_IER, serial_in(up, UART_IER) | mask);
+	struct uart_port *port = &up->port;
+	unsigned int flags;
+	unsigned int ier;
+
+	if (uart_console(port))
+		console_atomic_lock(&flags);
+
+	ier = serial_in(up, UART_IER);
+	serial_out(up, UART_IER, ier | mask);
+
+	if (uart_console(port))
+		console_atomic_unlock(flags);
 }
 
 static void mtk8250_set_flow_ctrl(struct uart_8250_port *up, int mode)
@ drivers/tty/serial/8250/8250_port.c:765 @ static void serial8250_set_sleep(struct uart_8250_port *p, int sleep)
 			serial_out(p, UART_EFR, UART_EFR_ECB);
 			serial_out(p, UART_LCR, 0);
 		}
-		serial_out(p, UART_IER, sleep ? UART_IERX_SLEEP : 0);
+		serial8250_set_IER(p, sleep ? UART_IERX_SLEEP : 0);
 		if (p->capabilities & UART_CAP_EFR) {
 			serial_out(p, UART_LCR, UART_LCR_CONF_MODE_B);
 			serial_out(p, UART_EFR, efr);
@ drivers/tty/serial/8250/8250_port.c:1439 @ static void serial8250_stop_rx(struct uart_port *port)
 
 	up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
 	up->port.read_status_mask &= ~UART_LSR_DR;
-	serial_port_out(port, UART_IER, up->ier);
+	serial8250_set_IER(up, up->ier);
 
 	serial8250_rpm_put(up);
 }
@ drivers/tty/serial/8250/8250_port.c:1469 @ void serial8250_em485_stop_tx(struct uart_8250_port *p)
 		serial8250_clear_and_reinit_fifos(p);
 
 		p->ier |= UART_IER_RLSI | UART_IER_RDI;
-		serial_port_out(&p->port, UART_IER, p->ier);
+		serial8250_set_IER(p, p->ier);
 	}
 }
 EXPORT_SYMBOL_GPL(serial8250_em485_stop_tx);
@ drivers/tty/serial/8250/8250_port.c:1697 @ static void serial8250_disable_ms(struct uart_port *port)
 	mctrl_gpio_disable_ms(up->gpios);
 
 	up->ier &= ~UART_IER_MSI;
-	serial_port_out(port, UART_IER, up->ier);
+	serial8250_set_IER(up, up->ier);
 }
 
 static void serial8250_enable_ms(struct uart_port *port)
@ drivers/tty/serial/8250/8250_port.c:1713 @ static void serial8250_enable_ms(struct uart_port *port)
 	up->ier |= UART_IER_MSI;
 
 	serial8250_rpm_get(up);
-	serial_port_out(port, UART_IER, up->ier);
+	serial8250_set_IER(up, up->ier);
 	serial8250_rpm_put(up);
 }
 
@ drivers/tty/serial/8250/8250_port.c:2133 @ static void serial8250_put_poll_char(struct uart_port *port,
 	struct uart_8250_port *up = up_to_u8250p(port);
 
 	serial8250_rpm_get(up);
-	/*
-	 *	First save the IER then disable the interrupts
-	 */
-	ier = serial_port_in(port, UART_IER);
-	if (up->capabilities & UART_CAP_UUE)
-		serial_port_out(port, UART_IER, UART_IER_UUE);
-	else
-		serial_port_out(port, UART_IER, 0);
+	ier = serial8250_clear_IER(up);
 
 	wait_for_xmitr(up, BOTH_EMPTY);
 	/*
@ drivers/tty/serial/8250/8250_port.c:2146 @ static void serial8250_put_poll_char(struct uart_port *port,
 	 *	and restore the IER
 	 */
 	wait_for_xmitr(up, BOTH_EMPTY);
-	serial_port_out(port, UART_IER, ier);
+	serial8250_set_IER(up, ier);
 	serial8250_rpm_put(up);
 }
 
@ drivers/tty/serial/8250/8250_port.c:2449 @ void serial8250_do_shutdown(struct uart_port *port)
 	 */
 	spin_lock_irqsave(&port->lock, flags);
 	up->ier = 0;
-	serial_port_out(port, UART_IER, 0);
+	serial8250_set_IER(up, 0);
 	spin_unlock_irqrestore(&port->lock, flags);
 
 	synchronize_irq(port->irq);
@ drivers/tty/serial/8250/8250_port.c:2805 @ serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios,
 	if (up->capabilities & UART_CAP_RTOIE)
 		up->ier |= UART_IER_RTOIE;
 
-	serial_port_out(port, UART_IER, up->ier);
+	serial8250_set_IER(up, up->ier);
 
 	if (up->capabilities & UART_CAP_EFR) {
 		unsigned char efr = 0;
@ drivers/tty/serial/8250/8250_port.c:3271 @ EXPORT_SYMBOL_GPL(serial8250_set_defaults);
 
 #ifdef CONFIG_SERIAL_8250_CONSOLE
 
-static void serial8250_console_putchar(struct uart_port *port, int ch)
+static void serial8250_console_putchar_locked(struct uart_port *port, int ch)
 {
 	struct uart_8250_port *up = up_to_u8250p(port);
 
@ drivers/tty/serial/8250/8250_port.c:3279 @ static void serial8250_console_putchar(struct uart_port *port, int ch)
 	serial_port_out(port, UART_TX, ch);
 }
 
+static void serial8250_console_putchar(struct uart_port *port, int ch)
+{
+	struct uart_8250_port *up = up_to_u8250p(port);
+	unsigned int flags;
+
+	wait_for_xmitr(up, UART_LSR_THRE);
+
+	console_atomic_lock(&flags);
+	serial8250_console_putchar_locked(port, ch);
+	console_atomic_unlock(flags);
+}
+
 /*
  *	Restore serial console when h/w power-off detected
  */
@ drivers/tty/serial/8250/8250_port.c:3312 @ static void serial8250_console_restore(struct uart_8250_port *up)
 	serial8250_out_MCR(up, UART_MCR_DTR | UART_MCR_RTS);
 }
 
+void serial8250_console_write_atomic(struct uart_8250_port *up,
+				     const char *s, unsigned int count)
+{
+	struct uart_port *port = &up->port;
+	unsigned int flags;
+	unsigned int ier;
+
+	console_atomic_lock(&flags);
+
+	touch_nmi_watchdog();
+
+	ier = serial8250_clear_IER(up);
+
+	if (atomic_fetch_inc(&up->console_printing)) {
+		uart_console_write(port, "\n", 1,
+				   serial8250_console_putchar_locked);
+	}
+	uart_console_write(port, s, count, serial8250_console_putchar_locked);
+	atomic_dec(&up->console_printing);
+
+	wait_for_xmitr(up, BOTH_EMPTY);
+	serial8250_set_IER(up, ier);
+
+	console_atomic_unlock(flags);
+}
+
 /*
  *	Print a string to the serial port trying not to disturb
  *	any possible real use of the port...
@ drivers/tty/serial/8250/8250_port.c:3354 @ void serial8250_console_write(struct uart_8250_port *up, const char *s,
 	struct uart_port *port = &up->port;
 	unsigned long flags;
 	unsigned int ier;
-	int locked = 1;
 
 	touch_nmi_watchdog();
 
-	if (oops_in_progress)
-		locked = spin_trylock_irqsave(&port->lock, flags);
-	else
-		spin_lock_irqsave(&port->lock, flags);
-
-	/*
-	 *	First save the IER then disable the interrupts
-	 */
-	ier = serial_port_in(port, UART_IER);
+	spin_lock_irqsave(&port->lock, flags);
 
-	if (up->capabilities & UART_CAP_UUE)
-		serial_port_out(port, UART_IER, UART_IER_UUE);
-	else
-		serial_port_out(port, UART_IER, 0);
+	ier = serial8250_clear_IER(up);
 
 	/* check scratch reg to see if port powered off during system sleep */
 	if (up->canary && (up->canary != serial_port_in(port, UART_SCR))) {
@ drivers/tty/serial/8250/8250_port.c:3373 @ void serial8250_console_write(struct uart_8250_port *up, const char *s,
 		mdelay(port->rs485.delay_rts_before_send);
 	}
 
+	atomic_inc(&up->console_printing);
 	uart_console_write(port, s, count, serial8250_console_putchar);
+	atomic_dec(&up->console_printing);
 
 	/*
 	 *	Finally, wait for transmitter to become empty
@ drivers/tty/serial/8250/8250_port.c:3388 @ void serial8250_console_write(struct uart_8250_port *up, const char *s,
 		if (em485->tx_stopped)
 			up->rs485_stop_tx(up);
 	}
-
-	serial_port_out(port, UART_IER, ier);
+	serial8250_set_IER(up, ier);
 
 	/*
 	 *	The receive handling will happen properly because the
@ drivers/tty/serial/8250/8250_port.c:3400 @ void serial8250_console_write(struct uart_8250_port *up, const char *s,
 	if (up->msr_saved_flags)
 		serial8250_modem_status(up);
 
-	if (locked)
-		spin_unlock_irqrestore(&port->lock, flags);
+	spin_unlock_irqrestore(&port->lock, flags);
 }
 
 static unsigned int probe_baud(struct uart_port *port)
@ drivers/tty/serial/8250/8250_port.c:3420 @ static unsigned int probe_baud(struct uart_port *port)
 
 int serial8250_console_setup(struct uart_port *port, char *options, bool probe)
 {
+	struct uart_8250_port *up = up_to_u8250p(port);
 	int baud = 9600;
 	int bits = 8;
 	int parity = 'n';
@ drivers/tty/serial/8250/8250_port.c:3430 @ int serial8250_console_setup(struct uart_port *port, char *options, bool probe)
 	if (!port->iobase && !port->membase)
 		return -ENODEV;
 
+	atomic_set(&up->console_printing, 0);
+
 	if (options)
 		uart_parse_options(options, &baud, &parity, &bits, &flow);
 	else if (probe)
@ drivers/tty/serial/amba-pl011.c:2204 @ pl011_console_write(struct console *co, const char *s, unsigned int count)
 {
 	struct uart_amba_port *uap = amba_ports[co->index];
 	unsigned int old_cr = 0, new_cr;
-	unsigned long flags;
+	unsigned long flags = 0;
 	int locked = 1;
 
 	clk_enable(uap->clk);
 
-	local_irq_save(flags);
+	/*
+	 * local_irq_save(flags);
+	 *
+	 * This local_irq_save() is nonsense. If we come in via sysrq
+	 * handling then interrupts are already disabled. Aside of
+	 * that the port.sysrq check is racy on SMP regardless.
+	*/
 	if (uap->port.sysrq)
 		locked = 0;
 	else if (oops_in_progress)
-		locked = spin_trylock(&uap->port.lock);
+		locked = spin_trylock_irqsave(&uap->port.lock, flags);
 	else
-		spin_lock(&uap->port.lock);
+		spin_lock_irqsave(&uap->port.lock, flags);
 
 	/*
 	 *	First save the CR then disable the interrupts
@ drivers/tty/serial/amba-pl011.c:2247 @ pl011_console_write(struct console *co, const char *s, unsigned int count)
 		pl011_write(old_cr, uap, REG_CR);
 
 	if (locked)
-		spin_unlock(&uap->port.lock);
-	local_irq_restore(flags);
+		spin_unlock_irqrestore(&uap->port.lock, flags);
 
 	clk_disable(uap->clk);
 }
@ drivers/tty/serial/omap-serial.c:1314 @ serial_omap_console_write(struct console *co, const char *s,
 
 	pm_runtime_get_sync(up->dev);
 
-	local_irq_save(flags);
-	if (up->port.sysrq)
-		locked = 0;
-	else if (oops_in_progress)
-		locked = spin_trylock(&up->port.lock);
+	if (up->port.sysrq || oops_in_progress)
+		locked = spin_trylock_irqsave(&up->port.lock, flags);
 	else
-		spin_lock(&up->port.lock);
+		spin_lock_irqsave(&up->port.lock, flags);
 
 	/*
 	 * First save the IER then disable the interrupts
@ drivers/tty/serial/omap-serial.c:1346 @ serial_omap_console_write(struct console *co, const char *s,
 	pm_runtime_mark_last_busy(up->dev);
 	pm_runtime_put_autosuspend(up->dev);
 	if (locked)
-		spin_unlock(&up->port.lock);
-	local_irq_restore(flags);
+		spin_unlock_irqrestore(&up->port.lock, flags);
 }
 
 static int __init
@ fs/afs/dir_silly.c:242 @ int afs_silly_iput(struct dentry *dentry, struct inode *inode)
 	struct dentry *alias;
 	int ret;
 
-	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+	DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
 
 	_enter("%p{%pd},%llx", dentry, dentry, vnode->fid.vnode);
 
@ fs/aio.c:46 @
 #include <linux/mount.h>
 #include <linux/pseudo_fs.h>
 
-#include <asm/kmap_types.h>
 #include <linux/uaccess.h>
 #include <linux/nospec.h>
 
@ fs/btrfs/ctree.h:20 @
 #include <linux/wait.h>
 #include <linux/slab.h>
 #include <trace/events/btrfs.h>
-#include <asm/kmap_types.h>
 #include <asm/unaligned.h>
 #include <linux/pagemap.h>
 #include <linux/btrfs.h>
@ fs/cifs/readdir.c:84 @ cifs_prime_dcache(struct dentry *parent, struct qstr *name,
 	struct inode *inode;
 	struct super_block *sb = parent->d_sb;
 	struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
-	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+	DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
 
 	cifs_dbg(FYI, "%s: for %s\n", __func__, name->name);
 
@ fs/dcache.c:2506 @ EXPORT_SYMBOL(d_rehash);
 static inline unsigned start_dir_add(struct inode *dir)
 {
 
+	preempt_disable_rt();
 	for (;;) {
-		unsigned n = dir->i_dir_seq;
-		if (!(n & 1) && cmpxchg(&dir->i_dir_seq, n, n + 1) == n)
+		unsigned n = dir->__i_dir_seq;
+		if (!(n & 1) && cmpxchg(&dir->__i_dir_seq, n, n + 1) == n)
 			return n;
 		cpu_relax();
 	}
@ fs/dcache.c:2517 @ static inline unsigned start_dir_add(struct inode *dir)
 
 static inline void end_dir_add(struct inode *dir, unsigned n)
 {
-	smp_store_release(&dir->i_dir_seq, n + 2);
+	smp_store_release(&dir->__i_dir_seq, n + 2);
+	preempt_enable_rt();
 }
 
 static void d_wait_lookup(struct dentry *dentry)
 {
-	if (d_in_lookup(dentry)) {
-		DECLARE_WAITQUEUE(wait, current);
-		add_wait_queue(dentry->d_wait, &wait);
-		do {
-			set_current_state(TASK_UNINTERRUPTIBLE);
-			spin_unlock(&dentry->d_lock);
-			schedule();
-			spin_lock(&dentry->d_lock);
-		} while (d_in_lookup(dentry));
-	}
+	struct swait_queue __wait;
+
+	if (!d_in_lookup(dentry))
+		return;
+
+	INIT_LIST_HEAD(&__wait.task_list);
+	do {
+		prepare_to_swait_exclusive(dentry->d_wait, &__wait, TASK_UNINTERRUPTIBLE);
+		spin_unlock(&dentry->d_lock);
+		schedule();
+		spin_lock(&dentry->d_lock);
+	} while (d_in_lookup(dentry));
+	finish_swait(dentry->d_wait, &__wait);
 }
 
 struct dentry *d_alloc_parallel(struct dentry *parent,
 				const struct qstr *name,
-				wait_queue_head_t *wq)
+				struct swait_queue_head *wq)
 {
 	unsigned int hash = name->hash;
 	struct hlist_bl_head *b = in_lookup_hash(parent, hash);
@ fs/dcache.c:2554 @ struct dentry *d_alloc_parallel(struct dentry *parent,
 
 retry:
 	rcu_read_lock();
-	seq = smp_load_acquire(&parent->d_inode->i_dir_seq);
+	seq = smp_load_acquire(&parent->d_inode->__i_dir_seq);
 	r_seq = read_seqbegin(&rename_lock);
 	dentry = __d_lookup_rcu(parent, name, &d_seq);
 	if (unlikely(dentry)) {
@ fs/dcache.c:2582 @ struct dentry *d_alloc_parallel(struct dentry *parent,
 	}
 
 	hlist_bl_lock(b);
-	if (unlikely(READ_ONCE(parent->d_inode->i_dir_seq) != seq)) {
+	if (unlikely(READ_ONCE(parent->d_inode->__i_dir_seq) != seq)) {
 		hlist_bl_unlock(b);
 		rcu_read_unlock();
 		goto retry;
@ fs/dcache.c:2655 @ void __d_lookup_done(struct dentry *dentry)
 	hlist_bl_lock(b);
 	dentry->d_flags &= ~DCACHE_PAR_LOOKUP;
 	__hlist_bl_del(&dentry->d_u.d_in_lookup_hash);
-	wake_up_all(dentry->d_wait);
+	swake_up_all(dentry->d_wait);
 	dentry->d_wait = NULL;
 	hlist_bl_unlock(b);
 	INIT_HLIST_NODE(&dentry->d_u.d_alias);
@ fs/fscache/internal.h:98 @ extern unsigned fscache_debug;
 extern struct kobject *fscache_root;
 extern struct workqueue_struct *fscache_object_wq;
 extern struct workqueue_struct *fscache_op_wq;
-DECLARE_PER_CPU(wait_queue_head_t, fscache_object_cong_wait);
 
 extern unsigned int fscache_hash(unsigned int salt, unsigned int *data, unsigned int n);
 
@ fs/fscache/main.c:44 @ struct kobject *fscache_root;
 struct workqueue_struct *fscache_object_wq;
 struct workqueue_struct *fscache_op_wq;
 
-DEFINE_PER_CPU(wait_queue_head_t, fscache_object_cong_wait);
-
 /* these values serve as lower bounds, will be adjusted in fscache_init() */
 static unsigned fscache_object_max_active = 4;
 static unsigned fscache_op_max_active = 2;
@ fs/fscache/main.c:139 @ unsigned int fscache_hash(unsigned int salt, unsigned int *data, unsigned int n)
 static int __init fscache_init(void)
 {
 	unsigned int nr_cpus = num_possible_cpus();
-	unsigned int cpu;
 	int ret;
 
 	fscache_object_max_active =
@ fs/fscache/main.c:161 @ static int __init fscache_init(void)
 	if (!fscache_op_wq)
 		goto error_op_wq;
 
-	for_each_possible_cpu(cpu)
-		init_waitqueue_head(&per_cpu(fscache_object_cong_wait, cpu));
-
 	ret = fscache_proc_init();
 	if (ret < 0)
 		goto error_proc;
@ fs/fscache/object.c:810 @ void fscache_object_destroy(struct fscache_object *object)
 }
 EXPORT_SYMBOL(fscache_object_destroy);
 
+static DECLARE_WAIT_QUEUE_HEAD(fscache_object_cong_wait);
+
 /*
  * enqueue an object for metadata-type processing
  */
@ fs/fscache/object.c:820 @ void fscache_enqueue_object(struct fscache_object *object)
 	_enter("{OBJ%x}", object->debug_id);
 
 	if (fscache_get_object(object, fscache_obj_get_queue) >= 0) {
-		wait_queue_head_t *cong_wq =
-			&get_cpu_var(fscache_object_cong_wait);
 
 		if (queue_work(fscache_object_wq, &object->work)) {
 			if (fscache_object_congested())
-				wake_up(cong_wq);
+				wake_up(&fscache_object_cong_wait);
 		} else
 			fscache_put_object(object, fscache_obj_put_queue);
-
-		put_cpu_var(fscache_object_cong_wait);
 	}
 }
 
@ fs/fscache/object.c:843 @ void fscache_enqueue_object(struct fscache_object *object)
  */
 bool fscache_object_sleep_till_congested(signed long *timeoutp)
 {
-	wait_queue_head_t *cong_wq = this_cpu_ptr(&fscache_object_cong_wait);
 	DEFINE_WAIT(wait);
 
 	if (fscache_object_congested())
 		return true;
 
-	add_wait_queue_exclusive(cong_wq, &wait);
+	add_wait_queue_exclusive(&fscache_object_cong_wait, &wait);
 	if (!fscache_object_congested())
 		*timeoutp = schedule_timeout(*timeoutp);
-	finish_wait(cong_wq, &wait);
+	finish_wait(&fscache_object_cong_wait, &wait);
 
 	return fscache_object_congested();
 }
@ fs/fuse/readdir.c:161 @ static int fuse_direntplus_link(struct file *file,
 	struct inode *dir = d_inode(parent);
 	struct fuse_conn *fc;
 	struct inode *inode;
-	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+	DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
 
 	if (!o->nodeid) {
 		/*
@ fs/inode.c:161 @ int inode_init_always(struct super_block *sb, struct inode *inode)
 	inode->i_bdev = NULL;
 	inode->i_cdev = NULL;
 	inode->i_link = NULL;
-	inode->i_dir_seq = 0;
+	inode->__i_dir_seq = 0;
 	inode->i_rdev = 0;
 	inode->dirtied_when = 0;
 
@ fs/namei.c:1523 @ static struct dentry *__lookup_slow(const struct qstr *name,
 {
 	struct dentry *dentry, *old;
 	struct inode *inode = dir->d_inode;
-	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+	DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
 
 	/* Don't go there if it's already dead */
 	if (unlikely(IS_DEADDIR(inode)))
@ fs/namei.c:3017 @ static struct dentry *lookup_open(struct nameidata *nd, struct file *file,
 	struct dentry *dentry;
 	int error, create_error = 0;
 	umode_t mode = op->mode;
-	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+	DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
 
 	if (unlikely(IS_DEADDIR(dir_inode)))
 		return ERR_PTR(-ENOENT);
@ fs/namespace.c:17 @
 #include <linux/mnt_namespace.h>
 #include <linux/user_namespace.h>
 #include <linux/namei.h>
+#include <linux/delay.h>
 #include <linux/security.h>
 #include <linux/cred.h>
 #include <linux/idr.h>
@ fs/namespace.c:325 @ int __mnt_want_write(struct vfsmount *m)
 	 * incremented count after it has set MNT_WRITE_HOLD.
 	 */
 	smp_mb();
-	while (READ_ONCE(mnt->mnt.mnt_flags) & MNT_WRITE_HOLD)
-		cpu_relax();
+	while (READ_ONCE(mnt->mnt.mnt_flags) & MNT_WRITE_HOLD) {
+		preempt_enable();
+		cpu_chill();
+		preempt_disable();
+	}
 	/*
 	 * After the slowpath clears MNT_WRITE_HOLD, mnt_is_readonly will
 	 * be set to match its requirements. So we must not load that until
@ fs/nfs/dir.c:487 @ void nfs_prime_dcache(struct dentry *parent, struct nfs_entry *entry,
 		unsigned long dir_verifier)
 {
 	struct qstr filename = QSTR_INIT(entry->name, entry->len);
-	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+	DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
 	struct dentry *dentry;
 	struct dentry *alias;
 	struct inode *inode;
@ fs/nfs/dir.c:1673 @ int nfs_atomic_open(struct inode *dir, struct dentry *dentry,
 		    struct file *file, unsigned open_flags,
 		    umode_t mode)
 {
-	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+	DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
 	struct nfs_open_context *ctx;
 	struct dentry *res;
 	struct iattr attr = { .ia_valid = ATTR_OPEN };
@ fs/nfs/unlink.c:16 @
 #include <linux/sunrpc/clnt.h>
 #include <linux/nfs_fs.h>
 #include <linux/sched.h>
-#include <linux/wait.h>
+#include <linux/swait.h>
 #include <linux/namei.h>
 #include <linux/fsnotify.h>
 
@ fs/nfs/unlink.c:183 @ nfs_async_unlink(struct dentry *dentry, const struct qstr *name)
 
 	data->cred = get_current_cred();
 	data->res.dir_attr = &data->dir_attr;
-	init_waitqueue_head(&data->wq);
+	init_swait_queue_head(&data->wq);
 
 	status = -EBUSY;
 	spin_lock(&dentry->d_lock);
@ fs/proc/array.c:387 @ static inline void task_context_switch_counts(struct seq_file *m,
 static void task_cpus_allowed(struct seq_file *m, struct task_struct *task)
 {
 	seq_printf(m, "Cpus_allowed:\t%*pb\n",
-		   cpumask_pr_args(task->cpus_ptr));
+		   cpumask_pr_args(&task->cpus_mask));
 	seq_printf(m, "Cpus_allowed_list:\t%*pbl\n",
-		   cpumask_pr_args(task->cpus_ptr));
+		   cpumask_pr_args(&task->cpus_mask));
 }
 
 static inline void task_core_dumping(struct seq_file *m, struct mm_struct *mm)
@ fs/proc/base.c:99 @
 #include <linux/posix-timers.h>
 #include <linux/time_namespace.h>
 #include <linux/resctrl.h>
+#include <linux/swait.h>
 #include <trace/events/oom.h>
 #include "internal.h"
 #include "fd.h"
@ fs/proc/base.c:2042 @ bool proc_fill_cache(struct file *file, struct dir_context *ctx,
 
 	child = d_hash_and_lookup(dir, &qname);
 	if (!child) {
-		DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+		DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
 		child = d_alloc_parallel(dir, &qname, &wq);
 		if (IS_ERR(child))
 			goto end_instantiate;
@ fs/proc/proc_sysctl.c:686 @ static bool proc_sys_fill_cache(struct file *file,
 
 	child = d_lookup(dir, &qname);
 	if (!child) {
-		DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+		DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
 		child = d_alloc_parallel(dir, &qname, &wq);
 		if (IS_ERR(child))
 			return false;
@ fs/pstore/platform.c:386 @ void pstore_record_init(struct pstore_record *record,
  * end of the buffer.
  */
 static void pstore_dump(struct kmsg_dumper *dumper,
-			enum kmsg_dump_reason reason)
+			enum kmsg_dump_reason reason,
+			struct kmsg_dumper_iter *iter)
 {
 	unsigned long	total = 0;
 	const char	*why;
@ fs/pstore/platform.c:439 @ static void pstore_dump(struct kmsg_dumper *dumper,
 		dst_size -= header_size;
 
 		/* Write dump contents. */
-		if (!kmsg_dump_get_buffer(dumper, true, dst + header_size,
+		if (!kmsg_dump_get_buffer(iter, true, dst + header_size,
 					  dst_size, &dump_size))
 			break;
 
@ include/asm-generic/Kbuild:33 @ mandatory-y += irq.h
 mandatory-y += irq_regs.h
 mandatory-y += irq_work.h
 mandatory-y += kdebug.h
-mandatory-y += kmap_types.h
+mandatory-y += kmap_size.h
 mandatory-y += kprobes.h
 mandatory-y += linkage.h
 mandatory-y += local.h
@ include/asm-generic/hardirq.h:10 @
 
 typedef struct {
 	unsigned int __softirq_pending;
+#ifdef ARCH_WANTS_NMI_IRQSTAT
+	unsigned int __nmi_count;
+#endif
 } ____cacheline_aligned irq_cpustat_t;
 
-#include <linux/irq_cpustat.h>	/* Standard mappings for irq_cpustat_t above */
+DECLARE_PER_CPU_ALIGNED(irq_cpustat_t, irq_stat);
+
 #include <linux/irq.h>
 
 #ifndef ack_bad_irq
@ include/asm-generic/kmap_size.h:4 @
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_GENERIC_KMAP_SIZE_H
+#define _ASM_GENERIC_KMAP_SIZE_H
+
+/* For debug this provides guard pages between the maps */
+#ifdef CONFIG_DEBUG_HIGHMEM
+# define KM_MAX_IDX	33
+#else
+# define KM_MAX_IDX	16
+#endif
+
+#endif
@ include/asm-generic/kmap_types.h:1 @
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_GENERIC_KMAP_TYPES_H
-#define _ASM_GENERIC_KMAP_TYPES_H
-
-#ifdef __WITH_KM_FENCE
-# define KM_TYPE_NR 41
-#else
-# define KM_TYPE_NR 20
-#endif
-
-#endif
@ include/asm-generic/preempt.h:82 @ static __always_inline bool should_resched(int preempt_offset)
 }
 
 #ifdef CONFIG_PREEMPTION
+#ifdef CONFIG_PREEMPT_RT
+extern void preempt_schedule_lock(void);
+#endif
 extern asmlinkage void preempt_schedule(void);
 #define __preempt_schedule() preempt_schedule()
 extern asmlinkage void preempt_schedule_notrace(void);
@ include/linux/blkdev.h:164 @ struct request {
 	 */
 	union {
 		struct hlist_node hash;	/* merge hash */
-		struct list_head ipi_list;
+		struct llist_node ipi_list;
 	};
 
 	/*
@ include/linux/bottom_half.h:7 @
 
 #include <linux/preempt.h>
 
-#ifdef CONFIG_TRACE_IRQFLAGS
+#if defined(CONFIG_PREEMPT_RT) || defined(CONFIG_TRACE_IRQFLAGS)
 extern void __local_bh_disable_ip(unsigned long ip, unsigned int cnt);
 #else
 static __always_inline void __local_bh_disable_ip(unsigned long ip, unsigned int cnt)
@ include/linux/bottom_half.h:35 @ static inline void local_bh_enable(void)
 	__local_bh_enable_ip(_THIS_IP_, SOFTIRQ_DISABLE_OFFSET);
 }
 
+#ifdef CONFIG_PREEMPT_RT
+extern bool local_bh_blocked(void);
+#else
+static inline bool local_bh_blocked(void) { return false; }
+#endif
+
 #endif /* _LINUX_BH_H */
@ include/linux/console.h:19 @
 
 #include <linux/atomic.h>
 #include <linux/types.h>
+#include <linux/printk.h>
 
 struct vc_data;
 struct console_font_op;
@ include/linux/console.h:141 @ static inline int con_debug_leave(void)
 #define CON_ANYTIME	(16) /* Safe to call when cpu is offline */
 #define CON_BRL		(32) /* Used for a braille device */
 #define CON_EXTENDED	(64) /* Use the extended output format a la /dev/kmsg */
+#define CON_HANDOVER	(128) /* Device was previously a boot console. */
 
 struct console {
 	char	name[16];
 	void	(*write)(struct console *, const char *, unsigned);
+	void	(*write_atomic)(struct console *co, const char *s, unsigned int count);
 	int	(*read)(struct console *, char *, unsigned);
 	struct tty_driver *(*device)(struct console *, int *);
 	void	(*unblank)(void);
@ include/linux/console.h:156 @ struct console {
 	short	flags;
 	short	index;
 	int	cflag;
+#ifdef CONFIG_PRINTK
+	char	sync_buf[CONSOLE_LOG_MAX];
+#endif
+	atomic64_t printk_seq;
+	struct task_struct *thread;
 	uint	ispeed;
 	uint	ospeed;
 	void	*data;
@ include/linux/console.h:243 @ extern void console_init(void);
 void dummycon_register_output_notifier(struct notifier_block *nb);
 void dummycon_unregister_output_notifier(struct notifier_block *nb);
 
+extern void console_atomic_lock(unsigned int *flags);
+extern void console_atomic_unlock(unsigned int flags);
+
 #endif /* _LINUX_CONSOLE_H */
@ include/linux/cpuhotplug.h:156 @ enum cpuhp_state {
 	CPUHP_AP_ONLINE,
 	CPUHP_TEARDOWN_CPU,
 	CPUHP_AP_ONLINE_IDLE,
+	CPUHP_AP_SCHED_WAIT_EMPTY,
 	CPUHP_AP_SMPBOOT_THREADS,
 	CPUHP_AP_X86_VDSO_VMA_ONLINE,
 	CPUHP_AP_IRQ_AFFINITY_ONLINE,
@ include/linux/cpumask.h:202 @ static inline int cpumask_any_and_distribute(const struct cpumask *src1p,
 	return cpumask_next_and(-1, src1p, src2p);
 }
 
+static inline int cpumask_any_distribute(const struct cpumask *srcp)
+{
+	return cpumask_first(srcp);
+}
+
 #define for_each_cpu(cpu, mask)			\
 	for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)
 #define for_each_cpu_not(cpu, mask)		\
@ include/linux/cpumask.h:260 @ int cpumask_any_but(const struct cpumask *mask, unsigned int cpu);
 unsigned int cpumask_local_spread(unsigned int i, int node);
 int cpumask_any_and_distribute(const struct cpumask *src1p,
 			       const struct cpumask *src2p);
+int cpumask_any_distribute(const struct cpumask *srcp);
 
 /**
  * for_each_cpu - iterate over every cpu in a mask
@ include/linux/dcache.h:109 @ struct dentry {
 
 	union {
 		struct list_head d_lru;		/* LRU list */
-		wait_queue_head_t *d_wait;	/* in-lookup ones only */
+		struct swait_queue_head *d_wait;	/* in-lookup ones only */
 	};
 	struct list_head d_child;	/* child of parent list */
 	struct list_head d_subdirs;	/* our children */
@ include/linux/dcache.h:241 @ extern void d_set_d_op(struct dentry *dentry, const struct dentry_operations *op
 extern struct dentry * d_alloc(struct dentry *, const struct qstr *);
 extern struct dentry * d_alloc_anon(struct super_block *);
 extern struct dentry * d_alloc_parallel(struct dentry *, const struct qstr *,
-					wait_queue_head_t *);
+					struct swait_queue_head *);
 extern struct dentry * d_splice_alias(struct inode *, struct dentry *);
 extern struct dentry * d_add_ci(struct dentry *, struct inode *, struct qstr *);
 extern struct dentry * d_exact_alias(struct dentry *, struct inode *);
@ include/linux/debug_locks.h:6 @
 #define __LINUX_DEBUG_LOCKING_H
 
 #include <linux/atomic.h>
-#include <linux/bug.h>
-#include <linux/printk.h>
+#include <linux/cache.h>
 
 struct task_struct;
 
@ include/linux/delay.h:79 @ static inline void fsleep(unsigned long usecs)
 		msleep(DIV_ROUND_UP(usecs, 1000));
 }
 
+#ifdef CONFIG_PREEMPT_RT
+extern void cpu_chill(void);
+#else
+# define cpu_chill()	cpu_relax()
+#endif
+
 #endif /* defined(_LINUX_DELAY_H) */
@ include/linux/entry-common.h:72 @
 
 #define EXIT_TO_USER_MODE_WORK						\
 	(_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_UPROBE |		\
-	 _TIF_NEED_RESCHED | _TIF_PATCH_PENDING |			\
+	 _TIF_NEED_RESCHED_MASK | _TIF_PATCH_PENDING |			\
 	 ARCH_EXIT_TO_USER_MODE_WORK)
 
 /**
@ include/linux/fs.h:702 @ struct inode {
 		struct block_device	*i_bdev;
 		struct cdev		*i_cdev;
 		char			*i_link;
-		unsigned		i_dir_seq;
+		unsigned		__i_dir_seq;
 	};
 
 	__u32			i_generation;
@ include/linux/hardirq.h:9 @
 #include <linux/preempt.h>
 #include <linux/lockdep.h>
 #include <linux/ftrace_irq.h>
+#include <linux/sched.h>
 #include <linux/vtime.h>
 #include <asm/hardirq.h>
 
@ include/linux/hardirq.h:36 @ static __always_inline void rcu_irq_enter_check_tick(void)
  */
 #define __irq_enter()					\
 	do {						\
-		account_irq_enter_time(current);	\
 		preempt_count_add(HARDIRQ_OFFSET);	\
 		lockdep_hardirq_enter();		\
+		account_hardirq_enter(current);		\
 	} while (0)
 
 /*
@ include/linux/hardirq.h:66 @ void irq_enter_rcu(void);
  */
 #define __irq_exit()					\
 	do {						\
+		account_hardirq_exit(current);		\
 		lockdep_hardirq_exit();			\
-		account_irq_exit_time(current);		\
 		preempt_count_sub(HARDIRQ_OFFSET);	\
 	} while (0)
 
@ include/linux/hardirq.h:119 @ extern void rcu_nmi_exit(void);
 	do {							\
 		lockdep_off();					\
 		arch_nmi_enter();				\
-		printk_nmi_enter();				\
 		BUG_ON(in_nmi() == NMI_MASK);			\
 		__preempt_count_add(NMI_OFFSET + HARDIRQ_OFFSET);	\
 	} while (0)
@ include/linux/hardirq.h:137 @ extern void rcu_nmi_exit(void);
 	do {							\
 		BUG_ON(!in_nmi());				\
 		__preempt_count_sub(NMI_OFFSET + HARDIRQ_OFFSET);	\
-		printk_nmi_exit();				\
 		arch_nmi_exit();				\
 		lockdep_on();					\
 	} while (0)
@ include/linux/highmem-internal.h:4 @
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_HIGHMEM_INTERNAL_H
+#define _LINUX_HIGHMEM_INTERNAL_H
+
+/*
+ * Outside of CONFIG_HIGHMEM to support X86 32bit iomap_atomic() cruft.
+ */
+#ifdef CONFIG_KMAP_LOCAL
+void *__kmap_local_pfn_prot(unsigned long pfn, pgprot_t prot);
+void *__kmap_local_page_prot(struct page *page, pgprot_t prot);
+void kunmap_local_indexed(void *vaddr);
+void kmap_local_fork(struct task_struct *tsk);
+void __kmap_local_sched_out(void);
+void __kmap_local_sched_in(void);
+static inline void kmap_assert_nomap(void)
+{
+	DEBUG_LOCKS_WARN_ON(current->kmap_ctrl.idx);
+}
+#else
+static inline void kmap_local_fork(struct task_struct *tsk) { }
+static inline void kmap_assert_nomap(void) { }
+#endif
+
+#ifdef CONFIG_HIGHMEM
+#include <asm/highmem.h>
+
+#ifndef ARCH_HAS_KMAP_FLUSH_TLB
+static inline void kmap_flush_tlb(unsigned long addr) { }
+#endif
+
+#ifndef kmap_prot
+#define kmap_prot PAGE_KERNEL
+#endif
+
+void *kmap_high(struct page *page);
+void kunmap_high(struct page *page);
+void __kmap_flush_unused(void);
+struct page *__kmap_to_page(void *addr);
+
+static inline void *kmap(struct page *page)
+{
+	void *addr;
+
+	might_sleep();
+	if (!PageHighMem(page))
+		addr = page_address(page);
+	else
+		addr = kmap_high(page);
+	kmap_flush_tlb((unsigned long)addr);
+	return addr;
+}
+
+static inline void kunmap(struct page *page)
+{
+	might_sleep();
+	if (!PageHighMem(page))
+		return;
+	kunmap_high(page);
+}
+
+static inline struct page *kmap_to_page(void *addr)
+{
+	return __kmap_to_page(addr);
+}
+
+static inline void kmap_flush_unused(void)
+{
+	__kmap_flush_unused();
+}
+
+static inline void *kmap_local_page(struct page *page)
+{
+	return __kmap_local_page_prot(page, kmap_prot);
+}
+
+static inline void *kmap_local_page_prot(struct page *page, pgprot_t prot)
+{
+	return __kmap_local_page_prot(page, prot);
+}
+
+static inline void *kmap_local_pfn(unsigned long pfn)
+{
+	return __kmap_local_pfn_prot(pfn, kmap_prot);
+}
+
+static inline void __kunmap_local(void *vaddr)
+{
+	kunmap_local_indexed(vaddr);
+}
+
+static inline void *kmap_atomic(struct page *page)
+{
+	if (IS_ENABLED(CONFIG_PREEMPT_RT))
+		migrate_disable();
+	else
+		preempt_disable();
+	pagefault_disable();
+	return __kmap_local_page_prot(page, kmap_prot);
+}
+
+static inline void __kunmap_atomic(void *addr)
+{
+	kunmap_local_indexed(addr);
+	pagefault_enable();
+	if (IS_ENABLED(CONFIG_PREEMPT_RT))
+		migrate_enable();
+	else
+		preempt_enable();
+}
+
+unsigned int __nr_free_highpages(void);
+extern atomic_long_t _totalhigh_pages;
+
+static inline unsigned int nr_free_highpages(void)
+{
+	return __nr_free_highpages();
+}
+
+static inline unsigned long totalhigh_pages(void)
+{
+	return (unsigned long)atomic_long_read(&_totalhigh_pages);
+}
+
+static inline void totalhigh_pages_inc(void)
+{
+	atomic_long_inc(&_totalhigh_pages);
+}
+
+static inline void totalhigh_pages_add(long count)
+{
+	atomic_long_add(count, &_totalhigh_pages);
+}
+
+#else /* CONFIG_HIGHMEM */
+
+static inline struct page *kmap_to_page(void *addr)
+{
+	return virt_to_page(addr);
+}
+
+static inline void *kmap(struct page *page)
+{
+	might_sleep();
+	return page_address(page);
+}
+
+static inline void kunmap_high(struct page *page) { }
+static inline void kmap_flush_unused(void) { }
+
+static inline void kunmap(struct page *page)
+{
+#ifdef ARCH_HAS_FLUSH_ON_KUNMAP
+	kunmap_flush_on_unmap(page_address(page));
+#endif
+}
+
+static inline void *kmap_local_page(struct page *page)
+{
+	return page_address(page);
+}
+
+static inline void *kmap_local_page_prot(struct page *page, pgprot_t prot)
+{
+	return kmap_local_page(page);
+}
+
+static inline void *kmap_local_pfn(unsigned long pfn)
+{
+	return kmap_local_page(pfn_to_page(pfn));
+}
+
+static inline void __kunmap_local(void *addr)
+{
+#ifdef ARCH_HAS_FLUSH_ON_KUNMAP
+	kunmap_flush_on_unmap(addr);
+#endif
+}
+
+static inline void *kmap_atomic(struct page *page)
+{
+	if (IS_ENABLED(CONFIG_PREEMPT_RT))
+		migrate_disable();
+	else
+		preempt_disable();
+	pagefault_disable();
+	return page_address(page);
+}
+
+static inline void __kunmap_atomic(void *addr)
+{
+#ifdef ARCH_HAS_FLUSH_ON_KUNMAP
+	kunmap_flush_on_unmap(addr);
+#endif
+	pagefault_enable();
+	if (IS_ENABLED(CONFIG_PREEMPT_RT))
+		migrate_enable();
+	else
+		preempt_enable();
+}
+
+static inline unsigned int nr_free_highpages(void) { return 0; }
+static inline unsigned long totalhigh_pages(void) { return 0UL; }
+
+#endif /* CONFIG_HIGHMEM */
+
+/*
+ * Prevent people trying to call kunmap_atomic() as if it were kunmap()
+ * kunmap_atomic() should get the return value of kmap_atomic, not the page.
+ */
+#define kunmap_atomic(__addr)					\
+do {								\
+	BUILD_BUG_ON(__same_type((__addr), struct page *));	\
+	__kunmap_atomic(__addr);				\
+} while (0)
+
+#define kunmap_local(__addr)					\
+do {								\
+	BUILD_BUG_ON(__same_type((__addr), struct page *));	\
+	__kunmap_local(__addr);					\
+} while (0)
+
+#endif
@ include/linux/highmem.h:14 @
 
 #include <asm/cacheflush.h>
 
-#ifndef ARCH_HAS_FLUSH_ANON_PAGE
-static inline void flush_anon_page(struct vm_area_struct *vma, struct page *page, unsigned long vmaddr)
-{
-}
-#endif
+#include "highmem-internal.h"
 
-#ifndef ARCH_HAS_FLUSH_KERNEL_DCACHE_PAGE
-static inline void flush_kernel_dcache_page(struct page *page)
-{
-}
-static inline void flush_kernel_vmap_range(void *vaddr, int size)
-{
-}
-static inline void invalidate_kernel_vmap_range(void *vaddr, int size)
-{
-}
-#endif
-
-#include <asm/kmap_types.h>
-
-#ifdef CONFIG_HIGHMEM
-extern void *kmap_atomic_high_prot(struct page *page, pgprot_t prot);
-extern void kunmap_atomic_high(void *kvaddr);
-#include <asm/highmem.h>
-
-#ifndef ARCH_HAS_KMAP_FLUSH_TLB
-static inline void kmap_flush_tlb(unsigned long addr) { }
-#endif
-
-#ifndef kmap_prot
-#define kmap_prot PAGE_KERNEL
-#endif
-
-void *kmap_high(struct page *page);
-static inline void *kmap(struct page *page)
-{
-	void *addr;
-
-	might_sleep();
-	if (!PageHighMem(page))
-		addr = page_address(page);
-	else
-		addr = kmap_high(page);
-	kmap_flush_tlb((unsigned long)addr);
-	return addr;
-}
-
-void kunmap_high(struct page *page);
-
-static inline void kunmap(struct page *page)
-{
-	might_sleep();
-	if (!PageHighMem(page))
-		return;
-	kunmap_high(page);
-}
-
-/*
- * kmap_atomic/kunmap_atomic is significantly faster than kmap/kunmap because
- * no global lock is needed and because the kmap code must perform a global TLB
- * invalidation when the kmap pool wraps.
+/**
+ * kmap - Map a page for long term usage
+ * @page:	Pointer to the page to be mapped
+ *
+ * Returns: The virtual address of the mapping
+ *
+ * Can only be invoked from preemptible task context because on 32bit
+ * systems with CONFIG_HIGHMEM enabled this function might sleep.
  *
- * However when holding an atomic kmap it is not legal to sleep, so atomic
- * kmaps are appropriate for short, tight code paths only.
+ * For systems with CONFIG_HIGHMEM=n and for pages in the low memory area
+ * this returns the virtual address of the direct kernel mapping.
  *
- * The use of kmap_atomic/kunmap_atomic is discouraged - kmap/kunmap
- * gives a more generic (and caching) interface. But kmap_atomic can
- * be used in IRQ contexts, so in some (very limited) cases we need
- * it.
+ * The returned virtual address is globally visible and valid up to the
+ * point where it is unmapped via kunmap(). The pointer can be handed to
+ * other contexts.
+ *
+ * For highmem pages on 32bit systems this can be slow as the mapping space
+ * is limited and protected by a global lock. In case that there is no
+ * mapping slot available the function blocks until a slot is released via
+ * kunmap().
  */
-static inline void *kmap_atomic_prot(struct page *page, pgprot_t prot)
-{
-	preempt_disable();
-	pagefault_disable();
-	if (!PageHighMem(page))
-		return page_address(page);
-	return kmap_atomic_high_prot(page, prot);
-}
-#define kmap_atomic(page)	kmap_atomic_prot(page, kmap_prot)
-
-/* declarations for linux/mm/highmem.c */
-unsigned int nr_free_highpages(void);
-extern atomic_long_t _totalhigh_pages;
-static inline unsigned long totalhigh_pages(void)
-{
-	return (unsigned long)atomic_long_read(&_totalhigh_pages);
-}
-
-static inline void totalhigh_pages_inc(void)
-{
-	atomic_long_inc(&_totalhigh_pages);
-}
-
-static inline void totalhigh_pages_dec(void)
-{
-	atomic_long_dec(&_totalhigh_pages);
-}
-
-static inline void totalhigh_pages_add(long count)
-{
-	atomic_long_add(count, &_totalhigh_pages);
-}
-
-static inline void totalhigh_pages_set(long val)
-{
-	atomic_long_set(&_totalhigh_pages, val);
-}
-
-void kmap_flush_unused(void);
+static inline void *kmap(struct page *page);
 
-struct page *kmap_to_page(void *addr);
-
-#else /* CONFIG_HIGHMEM */
+/**
+ * kunmap - Unmap the virtual address mapped by kmap()
+ * @addr:	Virtual address to be unmapped
+ *
+ * Counterpart to kmap(). A NOOP for CONFIG_HIGHMEM=n and for mappings of
+ * pages in the low memory area.
+ */
+static inline void kunmap(struct page *page);
 
-static inline unsigned int nr_free_highpages(void) { return 0; }
+/**
+ * kmap_to_page - Get the page for a kmap'ed address
+ * @addr:	The address to look up
+ *
+ * Returns: The page which is mapped to @addr.
+ */
+static inline struct page *kmap_to_page(void *addr);
 
-static inline struct page *kmap_to_page(void *addr)
-{
-	return virt_to_page(addr);
-}
+/**
+ * kmap_flush_unused - Flush all unused kmap mappings in order to
+ *		       remove stray mappings
+ */
+static inline void kmap_flush_unused(void);
 
-static inline unsigned long totalhigh_pages(void) { return 0UL; }
+/**
+ * kmap_local_page - Map a page for temporary usage
+ * @page:	Pointer to the page to be mapped
+ *
+ * Returns: The virtual address of the mapping
+ *
+ * Can be invoked from any context.
+ *
+ * Requires careful handling when nesting multiple mappings because the map
+ * management is stack based. The unmap has to be in the reverse order of
+ * the map operation:
+ *
+ * addr1 = kmap_local_page(page1);
+ * addr2 = kmap_local_page(page2);
+ * ...
+ * kunmap_local(addr2);
+ * kunmap_local(addr1);
+ *
+ * Unmapping addr1 before addr2 is invalid and causes malfunction.
+ *
+ * Contrary to kmap() mappings the mapping is only valid in the context of
+ * the caller and cannot be handed to other contexts.
+ *
+ * On CONFIG_HIGHMEM=n kernels and for low memory pages this returns the
+ * virtual address of the direct mapping. Only real highmem pages are
+ * temporarily mapped.
+ *
+ * While it is significantly faster than kmap() for the higmem case it
+ * comes with restrictions about the pointer validity. Only use when really
+ * necessary.
+ *
+ * On HIGHMEM enabled systems mapping a highmem page has the side effect of
+ * disabling migration in order to keep the virtual address stable across
+ * preemption. No caller of kmap_local_page() can rely on this side effect.
+ */
+static inline void *kmap_local_page(struct page *page);
 
-static inline void *kmap(struct page *page)
-{
-	might_sleep();
-	return page_address(page);
-}
+/**
+ * kmap_atomic - Atomically map a page for temporary usage - Deprecated!
+ * @page:	Pointer to the page to be mapped
+ *
+ * Returns: The virtual address of the mapping
+ *
+ * Effectively a wrapper around kmap_local_page() which disables pagefaults
+ * and preemption.
+ *
+ * Do not use in new code. Use kmap_local_page() instead.
+ */
+static inline void *kmap_atomic(struct page *page);
 
-static inline void kunmap_high(struct page *page)
-{
-}
+/**
+ * kunmap_atomic - Unmap the virtual address mapped by kmap_atomic()
+ * @addr:	Virtual address to be unmapped
+ *
+ * Counterpart to kmap_atomic().
+ *
+ * Effectively a wrapper around kunmap_local() which additionally undoes
+ * the side effects of kmap_atomic(), i.e. reenabling pagefaults and
+ * preemption.
+ */
 
-static inline void kunmap(struct page *page)
-{
-#ifdef ARCH_HAS_FLUSH_ON_KUNMAP
-	kunmap_flush_on_unmap(page_address(page));
-#endif
-}
+/* Highmem related interfaces for management code */
+static inline unsigned int nr_free_highpages(void);
+static inline unsigned long totalhigh_pages(void);
 
-static inline void *kmap_atomic(struct page *page)
+#ifndef ARCH_HAS_FLUSH_ANON_PAGE
+static inline void flush_anon_page(struct vm_area_struct *vma, struct page *page, unsigned long vmaddr)
 {
-	preempt_disable();
-	pagefault_disable();
-	return page_address(page);
 }
-#define kmap_atomic_prot(page, prot)	kmap_atomic(page)
-
-static inline void kunmap_atomic_high(void *addr)
-{
-	/*
-	 * Mostly nothing to do in the CONFIG_HIGHMEM=n case as kunmap_atomic()
-	 * handles re-enabling faults + preemption
-	 */
-#ifdef ARCH_HAS_FLUSH_ON_KUNMAP
-	kunmap_flush_on_unmap(addr);
 #endif
-}
-
-#define kmap_atomic_pfn(pfn)	kmap_atomic(pfn_to_page(pfn))
-
-#define kmap_flush_unused()	do {} while(0)
-
-#endif /* CONFIG_HIGHMEM */
-
-#if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32)
-
-DECLARE_PER_CPU(int, __kmap_atomic_idx);
 
-static inline int kmap_atomic_idx_push(void)
+#ifndef ARCH_HAS_FLUSH_KERNEL_DCACHE_PAGE
+static inline void flush_kernel_dcache_page(struct page *page)
 {
-	int idx = __this_cpu_inc_return(__kmap_atomic_idx) - 1;
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-	WARN_ON_ONCE(in_irq() && !irqs_disabled());
-	BUG_ON(idx >= KM_TYPE_NR);
-#endif
-	return idx;
 }
-
-static inline int kmap_atomic_idx(void)
+static inline void flush_kernel_vmap_range(void *vaddr, int size)
 {
-	return __this_cpu_read(__kmap_atomic_idx) - 1;
 }
-
-static inline void kmap_atomic_idx_pop(void)
+static inline void invalidate_kernel_vmap_range(void *vaddr, int size)
 {
-#ifdef CONFIG_DEBUG_HIGHMEM
-	int idx = __this_cpu_dec_return(__kmap_atomic_idx);
-
-	BUG_ON(idx < 0);
-#else
-	__this_cpu_dec(__kmap_atomic_idx);
-#endif
 }
-
 #endif
 
-/*
- * Prevent people trying to call kunmap_atomic() as if it were kunmap()
- * kunmap_atomic() should get the return value of kmap_atomic, not the page.
- */
-#define kunmap_atomic(addr)                                     \
-do {                                                            \
-	BUILD_BUG_ON(__same_type((addr), struct page *));       \
-	kunmap_atomic_high(addr);                                  \
-	pagefault_enable();                                     \
-	preempt_enable();                                       \
-} while (0)
-
-
 /* when CONFIG_HIGHMEM is not set these will be plain clear/copy_page */
 #ifndef clear_user_highpage
 static inline void clear_user_highpage(struct page *page, unsigned long vaddr)
@ include/linux/interrupt.h:563 @ struct softirq_action
 asmlinkage void do_softirq(void);
 asmlinkage void __do_softirq(void);
 
-#ifdef __ARCH_HAS_DO_SOFTIRQ
+#if defined(__ARCH_HAS_DO_SOFTIRQ) && !defined(CONFIG_PREEMPT_RT)
 void do_softirq_own_stack(void);
 #else
 static inline void do_softirq_own_stack(void)
@ include/linux/interrupt.h:657 @ enum
 	TASKLET_STATE_RUN	/* Tasklet is running (SMP only) */
 };
 
-#ifdef CONFIG_SMP
+#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT)
 static inline int tasklet_trylock(struct tasklet_struct *t)
 {
 	return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state);
 }
 
-static inline void tasklet_unlock(struct tasklet_struct *t)
-{
-	smp_mb__before_atomic();
-	clear_bit(TASKLET_STATE_RUN, &(t)->state);
-}
+void tasklet_unlock(struct tasklet_struct *t);
+void tasklet_unlock_wait(struct tasklet_struct *t);
+void tasklet_unlock_spin_wait(struct tasklet_struct *t);
 
-static inline void tasklet_unlock_wait(struct tasklet_struct *t)
-{
-	while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); }
-}
 #else
-#define tasklet_trylock(t) 1
-#define tasklet_unlock_wait(t) do { } while (0)
-#define tasklet_unlock(t) do { } while (0)
+static inline int tasklet_trylock(struct tasklet_struct *t) { return 1; }
+static inline void tasklet_unlock(struct tasklet_struct *t) { }
+static inline void tasklet_unlock_wait(struct tasklet_struct *t) { }
+static inline void tasklet_unlock_spin_wait(struct tasklet_struct *t) { }
 #endif
 
 extern void __tasklet_schedule(struct tasklet_struct *t);
@ include/linux/interrupt.h:696 @ static inline void tasklet_disable_nosync(struct tasklet_struct *t)
 	smp_mb__after_atomic();
 }
 
+/*
+ * Do not use in new code. Disabling tasklets from atomic contexts is
+ * error prone and should be avoided.
+ */
+static inline void tasklet_disable_in_atomic(struct tasklet_struct *t)
+{
+	tasklet_disable_nosync(t);
+	tasklet_unlock_spin_wait(t);
+	smp_mb();
+}
+
 static inline void tasklet_disable(struct tasklet_struct *t)
 {
 	tasklet_disable_nosync(t);
@ include/linux/io-mapping.h:63 @ io_mapping_fini(struct io_mapping *mapping)
 	iomap_free(mapping->base, mapping->size);
 }
 
-/* Atomic map/unmap */
+/* Temporary mappings which are only valid in the current context */
 static inline void __iomem *
-io_mapping_map_atomic_wc(struct io_mapping *mapping,
-			 unsigned long offset)
+io_mapping_map_local_wc(struct io_mapping *mapping, unsigned long offset)
 {
 	resource_size_t phys_addr;
 
 	BUG_ON(offset >= mapping->size);
 	phys_addr = mapping->base + offset;
-	return iomap_atomic_prot_pfn(PHYS_PFN(phys_addr), mapping->prot);
+	return __iomap_local_pfn_prot(PHYS_PFN(phys_addr), mapping->prot);
 }
 
-static inline void
-io_mapping_unmap_atomic(void __iomem *vaddr)
+static inline void io_mapping_unmap_local(void __iomem *vaddr)
 {
-	iounmap_atomic(vaddr);
+	kunmap_local_indexed((void __force *)vaddr);
 }
 
 static inline void __iomem *
@ include/linux/io-mapping.h:98 @ io_mapping_unmap(void __iomem *vaddr)
 	iounmap(vaddr);
 }
 
-#else
+#else  /* HAVE_ATOMIC_IOMAP */
 
 #include <linux/uaccess.h>
 
@ include/linux/io-mapping.h:145 @ io_mapping_unmap(void __iomem *vaddr)
 {
 }
 
-/* Atomic map/unmap */
+/* Temporary mappings which are only valid in the current context */
 static inline void __iomem *
-io_mapping_map_atomic_wc(struct io_mapping *mapping,
-			 unsigned long offset)
+io_mapping_map_local_wc(struct io_mapping *mapping, unsigned long offset)
 {
-	preempt_disable();
-	pagefault_disable();
 	return io_mapping_map_wc(mapping, offset, PAGE_SIZE);
 }
 
-static inline void
-io_mapping_unmap_atomic(void __iomem *vaddr)
+static inline void io_mapping_unmap_local(void __iomem *vaddr)
 {
 	io_mapping_unmap(vaddr);
-	pagefault_enable();
-	preempt_enable();
 }
 
-#endif /* HAVE_ATOMIC_IOMAP */
+#endif /* !HAVE_ATOMIC_IOMAP */
 
 static inline struct io_mapping *
 io_mapping_create_wc(resource_size_t base,
@ include/linux/irq_cpustat.h:1 @
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef __irq_cpustat_h
-#define __irq_cpustat_h
-
-/*
- * Contains default mappings for irq_cpustat_t, used by almost every
- * architecture.  Some arch (like s390) have per cpu hardware pages and
- * they define their own mappings for irq_stat.
- *
- * Keith Owens <kaos@ocs.com.au> July 2000.
- */
-
-
-/*
- * Simple wrappers reducing source bloat.  Define all irq_stat fields
- * here, even ones that are arch dependent.  That way we get common
- * definitions instead of differing sets for each arch.
- */
-
-#ifndef __ARCH_IRQ_STAT
-DECLARE_PER_CPU_ALIGNED(irq_cpustat_t, irq_stat);	/* defined in asm/hardirq.h */
-#define __IRQ_STAT(cpu, member)	(per_cpu(irq_stat.member, cpu))
-#endif
-
-/* arch dependent irq_stat fields */
-#define nmi_count(cpu)		__IRQ_STAT((cpu), __nmi_count)	/* i386 */
-
-#endif	/* __irq_cpustat_h */
@ include/linux/irq_work.h:6 @
 #define _LINUX_IRQ_WORK_H
 
 #include <linux/smp_types.h>
+#include <linux/rcuwait.h>
 
 /*
  * An entry can be in one of four states:
@ include/linux/irq_work.h:26 @ struct irq_work {
 		};
 	};
 	void (*func)(struct irq_work *);
+	struct rcuwait irqwait;
 };
 
 static inline
@ include/linux/irq_work.h:34 @ void init_irq_work(struct irq_work *work, void (*func)(struct irq_work *))
 {
 	atomic_set(&work->flags, 0);
 	work->func = func;
+	rcuwait_init(&work->irqwait);
 }
 
 #define DEFINE_IRQ_WORK(name, _f) struct irq_work name = {	\
 		.flags = ATOMIC_INIT(0),			\
-		.func  = (_f)					\
+		.func  = (_f),					\
+		.irqwait = __RCUWAIT_INITIALIZER(irqwait),	\
 }
 
+#define __IRQ_WORK_INIT(_func, _flags) (struct irq_work){	\
+	.flags = ATOMIC_INIT(_flags),				\
+	.func = (_func),					\
+	.irqwait = __RCUWAIT_INITIALIZER(irqwait),		\
+}
+
+#define IRQ_WORK_INIT(_func) __IRQ_WORK_INIT(_func, 0)
+#define IRQ_WORK_INIT_LAZY(_func) __IRQ_WORK_INIT(_func, IRQ_WORK_LAZY)
+#define IRQ_WORK_INIT_HARD(_func) __IRQ_WORK_INIT(_func, IRQ_WORK_HARD_IRQ)
+
+static inline bool irq_work_is_busy(struct irq_work *work)
+{
+	return atomic_read(&work->flags) & IRQ_WORK_BUSY;
+}
+
+static inline bool irq_work_is_hard(struct irq_work *work)
+{
+	return atomic_read(&work->flags) & IRQ_WORK_HARD_IRQ;
+}
 
 bool irq_work_queue(struct irq_work *work);
 bool irq_work_queue_on(struct irq_work *work, int cpu);
@ include/linux/irqdesc.h:71 @ struct irq_desc {
 	unsigned int		irqs_unhandled;
 	atomic_t		threads_handled;
 	int			threads_handled_last;
+	u64			random_ip;
 	raw_spinlock_t		lock;
 	struct cpumask		*percpu_enabled;
 	const struct cpumask	*percpu_affinity;
@ include/linux/irqflags.h:74 @ do {						\
 do {						\
 	__this_cpu_dec(hardirq_context);	\
 } while (0)
-# define lockdep_softirq_enter()		\
-do {						\
-	current->softirq_context++;		\
-} while (0)
-# define lockdep_softirq_exit()			\
-do {						\
-	current->softirq_context--;		\
-} while (0)
 
 # define lockdep_hrtimer_enter(__hrtimer)		\
 ({							\
@ include/linux/irqflags.h:135 @ do {						\
 # define lockdep_irq_work_exit(__work)		do { } while (0)
 #endif
 
+#if defined(CONFIG_TRACE_IRQFLAGS) && !defined(CONFIG_PREEMPT_RT)
+# define lockdep_softirq_enter()		\
+do {						\
+	current->softirq_context++;		\
+} while (0)
+# define lockdep_softirq_exit()			\
+do {						\
+	current->softirq_context--;		\
+} while (0)
+
+#else
+# define lockdep_softirq_enter()		do { } while (0)
+# define lockdep_softirq_exit()			do { } while (0)
+#endif
+
 #if defined(CONFIG_IRQSOFF_TRACER) || \
 	defined(CONFIG_PREEMPT_TRACER)
  extern void stop_critical_timings(void);
@ include/linux/kernel.h:207 @ extern int _cond_resched(void);
 extern void ___might_sleep(const char *file, int line, int preempt_offset);
 extern void __might_sleep(const char *file, int line, int preempt_offset);
 extern void __cant_sleep(const char *file, int line, int preempt_offset);
+extern void __cant_migrate(const char *file, int line);
 
 /**
  * might_sleep - annotation for functions that can sleep
@ include/linux/kernel.h:223 @ extern void __cant_sleep(const char *file, int line, int preempt_offset);
  */
 # define might_sleep() \
 	do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
+
+# define might_sleep_no_state_check() \
+	do { ___might_sleep(__FILE__, __LINE__, 0); } while (0)
+
 /**
  * cant_sleep - annotation for functions that cannot sleep
  *
@ include/linux/kernel.h:235 @ extern void __cant_sleep(const char *file, int line, int preempt_offset);
 # define cant_sleep() \
 	do { __cant_sleep(__FILE__, __LINE__, 0); } while (0)
 # define sched_annotate_sleep()	(current->task_state_change = 0)
+
+/**
+ * cant_migrate - annotation for functions that cannot migrate
+ *
+ * Will print a stack trace if executed in code which is migratable
+ */
+# define cant_migrate()							\
+	do {								\
+		if (IS_ENABLED(CONFIG_SMP))				\
+			__cant_migrate(__FILE__, __LINE__);		\
+	} while (0)
+
 /**
  * non_block_start - annotate the start of section where sleeping is prohibited
  *
@ include/linux/kernel.h:270 @ extern void __cant_sleep(const char *file, int line, int preempt_offset);
   static inline void __might_sleep(const char *file, int line,
 				   int preempt_offset) { }
 # define might_sleep() do { might_resched(); } while (0)
+# define might_sleep_no_state_check() do { might_resched(); } while (0)
 # define cant_sleep() do { } while (0)
+# define cant_migrate()		do { } while (0)
 # define sched_annotate_sleep() do { } while (0)
 # define non_block_start() do { } while (0)
 # define non_block_end() do { } while (0)
@ include/linux/kernel.h:280 @ extern void __cant_sleep(const char *file, int line, int preempt_offset);
 
 #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
 
-#ifndef CONFIG_PREEMPT_RT
-# define cant_migrate()		cant_sleep()
-#else
-  /* Placeholder for now */
-# define cant_migrate()		do { } while (0)
-#endif
-
 /**
  * abs - return absolute value of an argument
  * @x: the value.  If it is unsigned type, it is converted to signed type first.
@ include/linux/kmsg_dump.h:32 @ enum kmsg_dump_reason {
 	KMSG_DUMP_MAX
 };
 
+/**
+ * struct kmsg_dumper_iter - iterator for kernel crash message dumper
+ * @active:	Flag that specifies if this is currently dumping
+ * @cur_seq:	Points to the oldest message to dump (private)
+ * @next_seq:	Points after the newest message to dump (private)
+ */
+struct kmsg_dumper_iter {
+	bool	active;
+	u64	cur_seq;
+	u64	next_seq;
+};
+
 /**
  * struct kmsg_dumper - kernel crash message dumper structure
  * @list:	Entry in the dumper list (private)
@ include/linux/kmsg_dump.h:54 @ enum kmsg_dump_reason {
  */
 struct kmsg_dumper {
 	struct list_head list;
-	void (*dump)(struct kmsg_dumper *dumper, enum kmsg_dump_reason reason);
+	void (*dump)(struct kmsg_dumper *dumper, enum kmsg_dump_reason reason,
+		     struct kmsg_dumper_iter *iter);
 	enum kmsg_dump_reason max_reason;
-	bool active;
 	bool registered;
-
-	/* private state of the kmsg iterator */
-	u32 cur_idx;
-	u32 next_idx;
-	u64 cur_seq;
-	u64 next_seq;
 };
 
 #ifdef CONFIG_PRINTK
 void kmsg_dump(enum kmsg_dump_reason reason);
 
-bool kmsg_dump_get_line_nolock(struct kmsg_dumper *dumper, bool syslog,
-			       char *line, size_t size, size_t *len);
-
-bool kmsg_dump_get_line(struct kmsg_dumper *dumper, bool syslog,
+bool kmsg_dump_get_line(struct kmsg_dumper_iter *iter, bool syslog,
 			char *line, size_t size, size_t *len);
 
-bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog,
-			  char *buf, size_t size, size_t *len);
-
-void kmsg_dump_rewind_nolock(struct kmsg_dumper *dumper);
+bool kmsg_dump_get_buffer(struct kmsg_dumper_iter *iter, bool syslog,
+			  char *buf, size_t size, size_t *len_out);
 
-void kmsg_dump_rewind(struct kmsg_dumper *dumper);
+void kmsg_dump_rewind(struct kmsg_dumper_iter *iter);
 
 int kmsg_dump_register(struct kmsg_dumper *dumper);
 
@ include/linux/kmsg_dump.h:81 @ static inline void kmsg_dump(enum kmsg_dump_reason reason)
 {
 }
 
-static inline bool kmsg_dump_get_line_nolock(struct kmsg_dumper *dumper,
-					     bool syslog, const char *line,
-					     size_t size, size_t *len)
-{
-	return false;
-}
-
-static inline bool kmsg_dump_get_line(struct kmsg_dumper *dumper, bool syslog,
+static inline bool kmsg_dump_get_line(struct kmsg_dumper_iter *iter, bool syslog,
 				const char *line, size_t size, size_t *len)
 {
 	return false;
 }
 
-static inline bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog,
+static inline bool kmsg_dump_get_buffer(struct kmsg_dumper_iter *iter, bool syslog,
 					char *buf, size_t size, size_t *len)
 {
 	return false;
 }
 
-static inline void kmsg_dump_rewind_nolock(struct kmsg_dumper *dumper)
-{
-}
-
-static inline void kmsg_dump_rewind(struct kmsg_dumper *dumper)
+static inline void kmsg_dump_rewind(struct kmsg_dumper_iter *iter)
 {
 }
 
@ include/linux/local_lock_internal.h:10 @
 #include <linux/lockdep.h>
 
 typedef struct {
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
+#ifdef CONFIG_PREEMPT_RT
+	spinlock_t              lock;
+	struct task_struct      *owner;
+	int                     nestcnt;
+
+#elif defined(CONFIG_DEBUG_LOCK_ALLOC)
 	struct lockdep_map	dep_map;
 	struct task_struct	*owner;
 #endif
 } local_lock_t;
 
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
+#ifdef CONFIG_PREEMPT_RT
+
+#define INIT_LOCAL_LOCK(lockname)	{	\
+	__SPIN_LOCK_UNLOCKED((lockname).lock),	\
+	.owner		= NULL,			\
+	.nestcnt	= 0,			\
+	}
+
+static inline void ___local_lock_init(local_lock_t *l)
+{
+	l->owner = NULL;
+	l->nestcnt = 0;
+}
+
+#define __local_lock_init(l)					\
+do {								\
+	spin_lock_init(&(l)->lock);				\
+	___local_lock_init(l);					\
+} while (0)
+
+#elif defined(CONFIG_DEBUG_LOCK_ALLOC)
+
 # define LOCAL_LOCK_DEBUG_INIT(lockname)		\
 	.dep_map = {					\
 		.name = #lockname,			\
@ include/linux/local_lock_internal.h:50 @ typedef struct {
 		.lock_type = LD_LOCK_PERCPU,		\
 	},						\
 	.owner = NULL,
+#endif
+
+#ifdef CONFIG_PREEMPT_RT
 
+static inline void local_lock_acquire(local_lock_t *l)
+{
+	if (l->owner != current) {
+		spin_lock(&l->lock);
+		DEBUG_LOCKS_WARN_ON(l->owner);
+		DEBUG_LOCKS_WARN_ON(l->nestcnt);
+		l->owner = current;
+	}
+	l->nestcnt++;
+}
+
+static inline void local_lock_release(local_lock_t *l)
+{
+	DEBUG_LOCKS_WARN_ON(l->nestcnt == 0);
+	DEBUG_LOCKS_WARN_ON(l->owner != current);
+	if (--l->nestcnt)
+		return;
+
+	l->owner = NULL;
+	spin_unlock(&l->lock);
+}
+
+#elif defined(CONFIG_DEBUG_LOCK_ALLOC)
 static inline void local_lock_acquire(local_lock_t *l)
 {
 	lock_map_acquire(&l->dep_map);
@ include/linux/local_lock_internal.h:102 @ static inline void local_lock_release(local_lock_t *l) { }
 static inline void local_lock_debug_init(local_lock_t *l) { }
 #endif /* !CONFIG_DEBUG_LOCK_ALLOC */
 
+#ifdef CONFIG_PREEMPT_RT
+
+#define __local_lock(lock)					\
+	do {							\
+		migrate_disable();				\
+		local_lock_acquire(this_cpu_ptr(lock));		\
+	} while (0)
+
+#define __local_unlock(lock)					\
+	do {							\
+		local_lock_release(this_cpu_ptr(lock));		\
+		migrate_enable();				\
+	} while (0)
+
+#define __local_lock_irq(lock)					\
+	do {							\
+		migrate_disable();				\
+		local_lock_acquire(this_cpu_ptr(lock));		\
+	} while (0)
+
+#define __local_lock_irqsave(lock, flags)			\
+	do {							\
+		migrate_disable();				\
+		flags = 0;					\
+		local_lock_acquire(this_cpu_ptr(lock));		\
+	} while (0)
+
+#define __local_unlock_irq(lock)				\
+	do {							\
+		local_lock_release(this_cpu_ptr(lock));		\
+		migrate_enable();				\
+	} while (0)
+
+#define __local_unlock_irqrestore(lock, flags)			\
+	do {							\
+		local_lock_release(this_cpu_ptr(lock));		\
+		migrate_enable();				\
+	} while (0)
+
+#else
+
 #define INIT_LOCAL_LOCK(lockname)	{ LOCAL_LOCK_DEBUG_INIT(lockname) }
 
 #define __local_lock_init(lock)					\
@ include/linux/local_lock_internal.h:162 @ do {								\
 		local_lock_acquire(this_cpu_ptr(lock));		\
 	} while (0)
 
+#define __local_unlock(lock)					\
+	do {							\
+		local_lock_release(this_cpu_ptr(lock));		\
+		preempt_enable();				\
+	} while (0)
+
 #define __local_lock_irq(lock)					\
 	do {							\
 		local_irq_disable();				\
@ include/linux/local_lock_internal.h:180 @ do {								\
 		local_lock_acquire(this_cpu_ptr(lock));		\
 	} while (0)
 
-#define __local_unlock(lock)					\
-	do {							\
-		local_lock_release(this_cpu_ptr(lock));		\
-		preempt_enable();				\
-	} while (0)
-
 #define __local_unlock_irq(lock)				\
 	do {							\
 		local_lock_release(this_cpu_ptr(lock));		\
@ include/linux/local_lock_internal.h:191 @ do {								\
 		local_lock_release(this_cpu_ptr(lock));		\
 		local_irq_restore(flags);			\
 	} while (0)
+
+#endif
@ include/linux/mm_types.h:15 @
 #include <linux/completion.h>
 #include <linux/cpumask.h>
 #include <linux/uprobes.h>
+#include <linux/rcupdate.h>
 #include <linux/page-flags-layout.h>
 #include <linux/workqueue.h>
 #include <linux/seqlock.h>
@ include/linux/mm_types.h:574 @ struct mm_struct {
 		bool tlb_flush_batched;
 #endif
 		struct uprobes_state uprobes_state;
+#ifdef CONFIG_PREEMPT_RT
+		struct rcu_head delayed_drop;
+#endif
 #ifdef CONFIG_HUGETLB_PAGE
 		atomic_long_t hugetlb_usage;
 #endif
@ include/linux/mutex.h:25 @
 
 struct ww_acquire_ctx;
 
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define __DEP_MAP_MUTEX_INITIALIZER(lockname)			\
+		, .dep_map = {					\
+			.name = #lockname,			\
+			.wait_type_inner = LD_WAIT_SLEEP,	\
+		}
+#else
+# define __DEP_MAP_MUTEX_INITIALIZER(lockname)
+#endif
+
+#ifdef CONFIG_PREEMPT_RT
+# include <linux/mutex_rt.h>
+#else
+
 /*
  * Simple, straightforward mutexes with strict semantics:
  *
@ include/linux/mutex.h:85 @ struct mutex {
 struct ww_class;
 struct ww_acquire_ctx;
 
-struct ww_mutex {
-	struct mutex base;
-	struct ww_acquire_ctx *ctx;
-#ifdef CONFIG_DEBUG_MUTEXES
-	struct ww_class *ww_class;
-#endif
-};
-
 /*
  * This is the control structure for tasks blocked on mutex,
  * which resides on the blocked task's kernel stack:
@ include/linux/mutex.h:128 @ do {									\
 	__mutex_init((mutex), #mutex, &__key);				\
 } while (0)
 
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-# define __DEP_MAP_MUTEX_INITIALIZER(lockname)			\
-		, .dep_map = {					\
-			.name = #lockname,			\
-			.wait_type_inner = LD_WAIT_SLEEP,	\
-		}
-#else
-# define __DEP_MAP_MUTEX_INITIALIZER(lockname)
-#endif
-
 #define __MUTEX_INITIALIZER(lockname) \
 		{ .owner = ATOMIC_LONG_INIT(0) \
 		, .wait_lock = __SPIN_LOCK_UNLOCKED(lockname.wait_lock) \
@ include/linux/mutex.h:223 @ enum mutex_trylock_recursive_enum {
 extern /* __deprecated */ __must_check enum mutex_trylock_recursive_enum
 mutex_trylock_recursive(struct mutex *lock);
 
+#endif /* !PREEMPT_RT */
+
 #endif /* __LINUX_MUTEX_H */
@ include/linux/mutex_rt.h:4 @
+// SPDX-License-Identifier: GPL-2.0-only
+#ifndef __LINUX_MUTEX_RT_H
+#define __LINUX_MUTEX_RT_H
+
+#ifndef __LINUX_MUTEX_H
+#error "Please include mutex.h"
+#endif
+
+#include <linux/rtmutex.h>
+
+/* FIXME: Just for __lockfunc */
+#include <linux/spinlock.h>
+
+struct mutex {
+	struct rt_mutex		lock;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+	struct lockdep_map	dep_map;
+#endif
+};
+
+#define __MUTEX_INITIALIZER(mutexname)					\
+	{								\
+		.lock = __RT_MUTEX_INITIALIZER(mutexname.lock)		\
+		__DEP_MAP_MUTEX_INITIALIZER(mutexname)			\
+	}
+
+#define DEFINE_MUTEX(mutexname)						\
+	struct mutex mutexname = __MUTEX_INITIALIZER(mutexname)
+
+extern void __mutex_do_init(struct mutex *lock, const char *name, struct lock_class_key *key);
+extern void __lockfunc _mutex_lock(struct mutex *lock);
+extern void __lockfunc _mutex_lock_io_nested(struct mutex *lock, int subclass);
+extern int __lockfunc _mutex_lock_interruptible(struct mutex *lock);
+extern int __lockfunc _mutex_lock_killable(struct mutex *lock);
+extern void __lockfunc _mutex_lock_nested(struct mutex *lock, int subclass);
+extern void __lockfunc _mutex_lock_nest_lock(struct mutex *lock, struct lockdep_map *nest_lock);
+extern int __lockfunc _mutex_lock_interruptible_nested(struct mutex *lock, int subclass);
+extern int __lockfunc _mutex_lock_killable_nested(struct mutex *lock, int subclass);
+extern int __lockfunc _mutex_trylock(struct mutex *lock);
+extern void __lockfunc _mutex_unlock(struct mutex *lock);
+
+#define mutex_is_locked(l)		rt_mutex_is_locked(&(l)->lock)
+#define mutex_lock(l)			_mutex_lock(l)
+#define mutex_lock_interruptible(l)	_mutex_lock_interruptible(l)
+#define mutex_lock_killable(l)		_mutex_lock_killable(l)
+#define mutex_trylock(l)		_mutex_trylock(l)
+#define mutex_unlock(l)			_mutex_unlock(l)
+#define mutex_lock_io(l)		_mutex_lock_io_nested(l, 0);
+
+#define __mutex_owner(l)		((l)->lock.owner)
+
+#ifdef CONFIG_DEBUG_MUTEXES
+#define mutex_destroy(l)		rt_mutex_destroy(&(l)->lock)
+#else
+static inline void mutex_destroy(struct mutex *lock) {}
+#endif
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define mutex_lock_nested(l, s)	_mutex_lock_nested(l, s)
+# define mutex_lock_interruptible_nested(l, s) \
+					_mutex_lock_interruptible_nested(l, s)
+# define mutex_lock_killable_nested(l, s) \
+					_mutex_lock_killable_nested(l, s)
+# define mutex_lock_io_nested(l, s)	_mutex_lock_io_nested(l, s)
+
+# define mutex_lock_nest_lock(lock, nest_lock)				\
+do {									\
+	typecheck(struct lockdep_map *, &(nest_lock)->dep_map);		\
+	_mutex_lock_nest_lock(lock, &(nest_lock)->dep_map);		\
+} while (0)
+
+#else
+# define mutex_lock_nested(l, s)	_mutex_lock(l)
+# define mutex_lock_interruptible_nested(l, s) \
+					_mutex_lock_interruptible(l)
+# define mutex_lock_killable_nested(l, s) \
+					_mutex_lock_killable(l)
+# define mutex_lock_nest_lock(lock, nest_lock) mutex_lock(lock)
+# define mutex_lock_io_nested(l, s)	_mutex_lock_io_nested(l, s)
+#endif
+
+# define mutex_init(mutex)				\
+do {							\
+	static struct lock_class_key __key;		\
+							\
+	rt_mutex_init(&(mutex)->lock);			\
+	__mutex_do_init((mutex), #mutex, &__key);	\
+} while (0)
+
+# define __mutex_init(mutex, name, key)			\
+do {							\
+	rt_mutex_init(&(mutex)->lock);			\
+	__mutex_do_init((mutex), name, key);		\
+} while (0)
+
+/**
+ * These values are chosen such that FAIL and SUCCESS match the
+ * values of the regular mutex_trylock().
+ */
+enum mutex_trylock_recursive_enum {
+	MUTEX_TRYLOCK_FAILED    = 0,
+	MUTEX_TRYLOCK_SUCCESS   = 1,
+	MUTEX_TRYLOCK_RECURSIVE,
+};
+/**
+ * mutex_trylock_recursive - trylock variant that allows recursive locking
+ * @lock: mutex to be locked
+ *
+ * This function should not be used, _ever_. It is purely for hysterical GEM
+ * raisins, and once those are gone this will be removed.
+ *
+ * Returns:
+ *  MUTEX_TRYLOCK_FAILED    - trylock failed,
+ *  MUTEX_TRYLOCK_SUCCESS   - lock acquired,
+ *  MUTEX_TRYLOCK_RECURSIVE - we already owned the lock.
+ */
+int __rt_mutex_owner_current(struct rt_mutex *lock);
+
+static inline /* __deprecated */ __must_check enum mutex_trylock_recursive_enum
+mutex_trylock_recursive(struct mutex *lock)
+{
+	if (unlikely(__rt_mutex_owner_current(&lock->lock)))
+		return MUTEX_TRYLOCK_RECURSIVE;
+
+	return mutex_trylock(lock);
+}
+
+extern int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock);
+
+#endif
@ include/linux/nfs_xdr.h:1678 @ struct nfs_unlinkdata {
 	struct nfs_removeargs args;
 	struct nfs_removeres res;
 	struct dentry *dentry;
-	wait_queue_head_t wq;
+	struct swait_queue_head wq;
 	const struct cred *cred;
 	struct nfs_fattr dir_attr;
 	long timeout;
@ include/linux/notifier.h:61 @ struct notifier_block {
 };
 
 struct atomic_notifier_head {
-	spinlock_t lock;
+	raw_spinlock_t lock;
 	struct notifier_block __rcu *head;
 };
 
@ include/linux/notifier.h:81 @ struct srcu_notifier_head {
 };
 
 #define ATOMIC_INIT_NOTIFIER_HEAD(name) do {	\
-		spin_lock_init(&(name)->lock);	\
+		raw_spin_lock_init(&(name)->lock);	\
 		(name)->head = NULL;		\
 	} while (0)
 #define BLOCKING_INIT_NOTIFIER_HEAD(name) do {	\
@ include/linux/notifier.h:98 @ extern void srcu_init_notifier_head(struct srcu_notifier_head *nh);
 		cleanup_srcu_struct(&(name)->srcu);
 
 #define ATOMIC_NOTIFIER_INIT(name) {				\
-		.lock = __SPIN_LOCK_UNLOCKED(name.lock),	\
+		.lock = __RAW_SPIN_LOCK_UNLOCKED(name.lock),	\
 		.head = NULL }
 #define BLOCKING_NOTIFIER_INIT(name) {				\
 		.rwsem = __RWSEM_INITIALIZER((name).rwsem),	\
@ include/linux/pid.h:6 @
 #define _LINUX_PID_H
 
 #include <linux/rculist.h>
+#include <linux/atomic.h>
 #include <linux/wait.h>
 #include <linux/refcount.h>
 
@ include/linux/preempt.h:80 @
 /* preempt_count() and related functions, depends on PREEMPT_NEED_RESCHED */
 #include <asm/preempt.h>
 
+#define nmi_count()	(preempt_count() & NMI_MASK)
 #define hardirq_count()	(preempt_count() & HARDIRQ_MASK)
-#define softirq_count()	(preempt_count() & SOFTIRQ_MASK)
-#define irq_count()	(preempt_count() & (HARDIRQ_MASK | SOFTIRQ_MASK \
-				 | NMI_MASK))
+#ifdef CONFIG_PREEMPT_RT
+# define softirq_count()	(current->softirq_disable_cnt & SOFTIRQ_MASK)
+#else
+# define softirq_count()	(preempt_count() & SOFTIRQ_MASK)
+#endif
+#define irq_count()	(nmi_count() | hardirq_count() | softirq_count())
 
 /*
- * Are we doing bottom half or hardware interrupt processing?
+ * Macros to retrieve the current execution context:
  *
- * in_irq()       - We're in (hard) IRQ context
+ * in_nmi()		- We're in NMI context
+ * in_hardirq()		- We're in hard IRQ context
+ * in_serving_softirq()	- We're in softirq context
+ * in_task()		- We're in task context
+ */
+#define in_nmi()		(nmi_count())
+#define in_hardirq()		(hardirq_count())
+#define in_serving_softirq()	(softirq_count() & SOFTIRQ_OFFSET)
+#define in_task()		(!(in_nmi() | in_hardirq() | in_serving_softirq()))
+
+/*
+ * The following macros are deprecated and should not be used in new code:
+ * in_irq()       - Obsolete version of in_hardirq()
  * in_softirq()   - We have BH disabled, or are processing softirqs
  * in_interrupt() - We're in NMI,IRQ,SoftIRQ context or have BH disabled
- * in_serving_softirq() - We're in softirq context
- * in_nmi()       - We're in NMI context
- * in_task()	  - We're in task context
- *
- * Note: due to the BH disabled confusion: in_softirq(),in_interrupt() really
- *       should not be used in new code.
  */
 #define in_irq()		(hardirq_count())
 #define in_softirq()		(softirq_count())
 #define in_interrupt()		(irq_count())
-#define in_serving_softirq()	(softirq_count() & SOFTIRQ_OFFSET)
-#define in_nmi()		(preempt_count() & NMI_MASK)
-#define in_task()		(!(preempt_count() & \
-				   (NMI_MASK | HARDIRQ_MASK | SOFTIRQ_OFFSET)))
 
 /*
  * The preempt_count offset after preempt_disable();
@ include/linux/preempt.h:124 @
 /*
  * The preempt_count offset after spin_lock()
  */
+#if !defined(CONFIG_PREEMPT_RT)
 #define PREEMPT_LOCK_OFFSET	PREEMPT_DISABLE_OFFSET
+#else
+#define PREEMPT_LOCK_OFFSET	0
+#endif
 
 /*
  * The preempt_count offset needed for things like:
@ include/linux/preempt.h:177 @ extern void preempt_count_sub(int val);
 #define preempt_count_inc() preempt_count_add(1)
 #define preempt_count_dec() preempt_count_sub(1)
 
+#ifdef CONFIG_PREEMPT_LAZY
+#define add_preempt_lazy_count(val)	do { preempt_lazy_count() += (val); } while (0)
+#define sub_preempt_lazy_count(val)	do { preempt_lazy_count() -= (val); } while (0)
+#define inc_preempt_lazy_count()	add_preempt_lazy_count(1)
+#define dec_preempt_lazy_count()	sub_preempt_lazy_count(1)
+#define preempt_lazy_count()		(current_thread_info()->preempt_lazy_count)
+#else
+#define add_preempt_lazy_count(val)	do { } while (0)
+#define sub_preempt_lazy_count(val)	do { } while (0)
+#define inc_preempt_lazy_count()	do { } while (0)
+#define dec_preempt_lazy_count()	do { } while (0)
+#define preempt_lazy_count()		(0)
+#endif
+
 #ifdef CONFIG_PREEMPT_COUNT
 
 #define preempt_disable() \
@ include/linux/preempt.h:199 @ do { \
 	barrier(); \
 } while (0)
 
+#define preempt_lazy_disable() \
+do { \
+	inc_preempt_lazy_count(); \
+	barrier(); \
+} while (0)
+
 #define sched_preempt_enable_no_resched() \
 do { \
 	barrier(); \
 	preempt_count_dec(); \
 } while (0)
 
-#define preempt_enable_no_resched() sched_preempt_enable_no_resched()
+#ifndef CONFIG_PREEMPT_RT
+# define preempt_enable_no_resched() sched_preempt_enable_no_resched()
+# define preempt_check_resched_rt() barrier();
+#else
+# define preempt_enable_no_resched() preempt_enable()
+# define preempt_check_resched_rt() preempt_check_resched()
+#endif
 
 #define preemptible()	(preempt_count() == 0 && !irqs_disabled())
 
@ include/linux/preempt.h:242 @ do { \
 		__preempt_schedule(); \
 } while (0)
 
+/*
+ * open code preempt_check_resched() because it is not exported to modules and
+ * used by local_unlock() or bpf_enable_instrumentation().
+ */
+#define preempt_lazy_enable() \
+do { \
+	dec_preempt_lazy_count(); \
+	barrier(); \
+	if (should_resched(0)) \
+		__preempt_schedule(); \
+} while (0)
+
 #else /* !CONFIG_PREEMPTION */
 #define preempt_enable() \
 do { \
@ include/linux/preempt.h:261 @ do { \
 	preempt_count_dec(); \
 } while (0)
 
+#define preempt_lazy_enable() \
+do { \
+	dec_preempt_lazy_count(); \
+	barrier(); \
+} while (0)
+
 #define preempt_enable_notrace() \
 do { \
 	barrier(); \
@ include/linux/preempt.h:305 @ do { \
 #define preempt_disable_notrace()		barrier()
 #define preempt_enable_no_resched_notrace()	barrier()
 #define preempt_enable_notrace()		barrier()
+#define preempt_check_resched_rt()		barrier()
 #define preemptible()				0
 
+#define preempt_lazy_disable()			barrier()
+#define preempt_lazy_enable()			barrier()
+
 #endif /* CONFIG_PREEMPT_COUNT */
 
 #ifdef MODULE
@ include/linux/preempt.h:329 @ do { \
 } while (0)
 #define preempt_fold_need_resched() \
 do { \
-	if (tif_need_resched()) \
+	if (tif_need_resched_now()) \
 		set_preempt_need_resched(); \
 } while (0)
 
+#ifdef CONFIG_PREEMPT_RT
+# define preempt_disable_rt()		preempt_disable()
+# define preempt_enable_rt()		preempt_enable()
+# define preempt_disable_nort()		barrier()
+# define preempt_enable_nort()		barrier()
+#else
+# define preempt_disable_rt()		barrier()
+# define preempt_enable_rt()		barrier()
+# define preempt_disable_nort()		preempt_disable()
+# define preempt_enable_nort()		preempt_enable()
+#endif
+
 #ifdef CONFIG_PREEMPT_NOTIFIERS
 
 struct preempt_notifier;
@ include/linux/preempt.h:395 @ static inline void preempt_notifier_init(struct preempt_notifier *notifier,
 
 #endif
 
-/**
- * migrate_disable - Prevent migration of the current task
+#ifdef CONFIG_SMP
+
+/*
+ * Migrate-Disable and why it is undesired.
  *
- * Maps to preempt_disable() which also disables preemption. Use
- * migrate_disable() to annotate that the intent is to prevent migration,
- * but not necessarily preemption.
+ * When a preempted task becomes elegible to run under the ideal model (IOW it
+ * becomes one of the M highest priority tasks), it might still have to wait
+ * for the preemptee's migrate_disable() section to complete. Thereby suffering
+ * a reduction in bandwidth in the exact duration of the migrate_disable()
+ * section.
  *
- * Can be invoked nested like preempt_disable() and needs the corresponding
- * number of migrate_enable() invocations.
- */
-static __always_inline void migrate_disable(void)
-{
-	preempt_disable();
-}
-
-/**
- * migrate_enable - Allow migration of the current task
+ * Per this argument, the change from preempt_disable() to migrate_disable()
+ * gets us:
+ *
+ * - a higher priority tasks gains reduced wake-up latency; with preempt_disable()
+ *   it would have had to wait for the lower priority task.
+ *
+ * - a lower priority tasks; which under preempt_disable() could've instantly
+ *   migrated away when another CPU becomes available, is now constrained
+ *   by the ability to push the higher priority task away, which might itself be
+ *   in a migrate_disable() section, reducing it's available bandwidth.
+ *
+ * IOW it trades latency / moves the interference term, but it stays in the
+ * system, and as long as it remains unbounded, the system is not fully
+ * deterministic.
  *
- * Counterpart to migrate_disable().
  *
- * As migrate_disable() can be invoked nested, only the outermost invocation
- * reenables migration.
+ * The reason we have it anyway.
+ *
+ * PREEMPT_RT breaks a number of assumptions traditionally held. By forcing a
+ * number of primitives into becoming preemptible, they would also allow
+ * migration. This turns out to break a bunch of per-cpu usage. To this end,
+ * all these primitives employ migirate_disable() to restore this implicit
+ * assumption.
+ *
+ * This is a 'temporary' work-around at best. The correct solution is getting
+ * rid of the above assumptions and reworking the code to employ explicit
+ * per-cpu locking or short preempt-disable regions.
+ *
+ * The end goal must be to get rid of migrate_disable(), alternatively we need
+ * a schedulability theory that does not depend on abritrary migration.
+ *
+ *
+ * Notes on the implementation.
+ *
+ * The implementation is particularly tricky since existing code patterns
+ * dictate neither migrate_disable() nor migrate_enable() is allowed to block.
+ * This means that it cannot use cpus_read_lock() to serialize against hotplug,
+ * nor can it easily migrate itself into a pending affinity mask change on
+ * migrate_enable().
+ *
+ *
+ * Note: even non-work-conserving schedulers like semi-partitioned depends on
+ *       migration, so migrate_disable() is not only a problem for
+ *       work-conserving schedulers.
  *
- * Currently mapped to preempt_enable().
  */
-static __always_inline void migrate_enable(void)
+extern void migrate_disable(void);
+extern void migrate_enable(void);
+
+#else
+
+static inline void migrate_disable(void)
 {
-	preempt_enable();
+	preempt_lazy_disable();
 }
 
+static inline void migrate_enable(void)
+{
+	preempt_lazy_enable();
+}
+
+#endif /* CONFIG_SMP */
+
 #endif /* __LINUX_PREEMPT_H */
@ include/linux/printk.h:49 @ static inline const char *printk_skip_headers(const char *buffer)
 
 #define CONSOLE_EXT_LOG_MAX	8192
 
+/*
+ * The maximum size of a record formatted for console printing
+ * (i.e. with the prefix prepended to every line).
+ */
+#define CONSOLE_LOG_MAX		4096
+
 /* printk's without a loglevel use this.. */
 #define MESSAGE_LOGLEVEL_DEFAULT CONFIG_MESSAGE_LOGLEVEL_DEFAULT
 
@ include/linux/printk.h:158 @ static inline __printf(1, 2) __cold
 void early_printk(const char *s, ...) { }
 #endif
 
-#ifdef CONFIG_PRINTK_NMI
-extern void printk_nmi_enter(void);
-extern void printk_nmi_exit(void);
-extern void printk_nmi_direct_enter(void);
-extern void printk_nmi_direct_exit(void);
-#else
-static inline void printk_nmi_enter(void) { }
-static inline void printk_nmi_exit(void) { }
-static inline void printk_nmi_direct_enter(void) { }
-static inline void printk_nmi_direct_exit(void) { }
-#endif /* PRINTK_NMI */
-
 struct dev_printk_info;
 
 #ifdef CONFIG_PRINTK
@ include/linux/printk.h:204 @ __printf(1, 2) void dump_stack_set_arch_desc(const char *fmt, ...);
 void dump_stack_print_info(const char *log_lvl);
 void show_regs_print_info(const char *log_lvl);
 extern asmlinkage void dump_stack(void) __cold;
-extern void printk_safe_flush(void);
-extern void printk_safe_flush_on_panic(void);
 #else
 static inline __printf(1, 0)
 int vprintk(const char *s, va_list args)
@ include/linux/printk.h:267 @ static inline void show_regs_print_info(const char *log_lvl)
 static inline void dump_stack(void)
 {
 }
-
-static inline void printk_safe_flush(void)
-{
-}
-
-static inline void printk_safe_flush_on_panic(void)
-{
-}
 #endif
 
 extern int kptr_restrict;
@ include/linux/printk.h:484 @ extern int kptr_restrict;
 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 #endif
 
+bool pr_flush(int timeout_ms, bool reset_on_progress);
+
 /*
  * ratelimited messages with local ratelimit_state,
  * no local ratelimit_state used in the !PRINTK case
@ include/linux/random.h:38 @ static inline void add_latent_entropy(void) {}
 
 extern void add_input_randomness(unsigned int type, unsigned int code,
 				 unsigned int value) __latent_entropy;
-extern void add_interrupt_randomness(int irq, int irq_flags) __latent_entropy;
+extern void add_interrupt_randomness(int irq, int irq_flags, __u64 ip) __latent_entropy;
 
 extern void get_random_bytes(void *buf, int nbytes);
 extern int wait_for_random_bytes(void);
@ include/linux/rbtree.h:22 @
 
 #include <linux/kernel.h>
 #include <linux/stddef.h>
+#include <linux/rbtree_type.h>
 #include <linux/rcupdate.h>
 
-struct rb_node {
-	unsigned long  __rb_parent_color;
-	struct rb_node *rb_right;
-	struct rb_node *rb_left;
-} __attribute__((aligned(sizeof(long))));
-    /* The alignment might seem pointless, but allegedly CRIS needs it */
-
-struct rb_root {
-	struct rb_node *rb_node;
-};
-
 #define rb_parent(r)   ((struct rb_node *)((r)->__rb_parent_color & ~3))
 
 #define RB_ROOT	(struct rb_root) { NULL, }
@ include/linux/rbtree.h:105 @ static inline void rb_link_node_rcu(struct rb_node *node, struct rb_node *parent
 			typeof(*pos), field); 1; }); \
 	     pos = n)
 
-/*
- * Leftmost-cached rbtrees.
- *
- * We do not cache the rightmost node based on footprint
- * size vs number of potential users that could benefit
- * from O(1) rb_last(). Just not worth it, users that want
- * this feature can always implement the logic explicitly.
- * Furthermore, users that want to cache both pointers may
- * find it a bit asymmetric, but that's ok.
- */
-struct rb_root_cached {
-	struct rb_root rb_root;
-	struct rb_node *rb_leftmost;
-};
-
 #define RB_ROOT_CACHED (struct rb_root_cached) { {NULL, }, NULL }
 
 /* Same as rb_first(), but O(1) */
@ include/linux/rbtree_type.h:4 @
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef _LINUX_RBTREE_TYPE_H
+#define _LINUX_RBTREE_TYPE_H
+
+struct rb_node {
+	unsigned long  __rb_parent_color;
+	struct rb_node *rb_right;
+	struct rb_node *rb_left;
+} __attribute__((aligned(sizeof(long))));
+/* The alignment might seem pointless, but allegedly CRIS needs it */
+
+struct rb_root {
+	struct rb_node *rb_node;
+};
+
+/*
+ * Leftmost-cached rbtrees.
+ *
+ * We do not cache the rightmost node based on footprint
+ * size vs number of potential users that could benefit
+ * from O(1) rb_last(). Just not worth it, users that want
+ * this feature can always implement the logic explicitly.
+ * Furthermore, users that want to cache both pointers may
+ * find it a bit asymmetric, but that's ok.
+ */
+struct rb_root_cached {
+	struct rb_root rb_root;
+	struct rb_node *rb_leftmost;
+};
+
+#endif
@ include/linux/rcupdate.h:57 @ void __rcu_read_unlock(void);
  * types of kernel builds, the rcu_read_lock() nesting depth is unknowable.
  */
 #define rcu_preempt_depth() (current->rcu_read_lock_nesting)
+#ifndef CONFIG_PREEMPT_RT
+#define sched_rcu_preempt_depth()	rcu_preempt_depth()
+#else
+static inline int sched_rcu_preempt_depth(void) { return 0; }
+#endif
 
 #else /* #ifdef CONFIG_PREEMPT_RCU */
 
@ include/linux/rcupdate.h:87 @ static inline int rcu_preempt_depth(void)
 	return 0;
 }
 
+#define sched_rcu_preempt_depth()	rcu_preempt_depth()
+
 #endif /* #else #ifdef CONFIG_PREEMPT_RCU */
 
 /* Internal to kernel */
@ include/linux/rcupdate.h:339 @ static inline void rcu_preempt_sleep_check(void) { }
 #define rcu_sleep_check()						\
 	do {								\
 		rcu_preempt_sleep_check();				\
-		RCU_LOCKDEP_WARN(lock_is_held(&rcu_bh_lock_map),	\
+		if (!IS_ENABLED(CONFIG_PREEMPT_RT))			\
+		    RCU_LOCKDEP_WARN(lock_is_held(&rcu_bh_lock_map),	\
 				 "Illegal context switch in RCU-bh read-side critical section"); \
 		RCU_LOCKDEP_WARN(lock_is_held(&rcu_sched_lock_map),	\
 				 "Illegal context switch in RCU-sched read-side critical section"); \
@ include/linux/rtmutex.h:17 @
 #define __LINUX_RT_MUTEX_H
 
 #include <linux/linkage.h>
-#include <linux/rbtree.h>
-#include <linux/spinlock_types.h>
+#include <linux/rbtree_type.h>
+#include <linux/spinlock_types_raw.h>
 
 extern int max_lock_depth; /* for sysctl */
 
+#ifdef CONFIG_DEBUG_MUTEXES
+#include <linux/debug_locks.h>
+#endif
+
 /**
  * The rt_mutex structure
  *
@ include/linux/rtmutex.h:38 @ struct rt_mutex {
 	raw_spinlock_t		wait_lock;
 	struct rb_root_cached   waiters;
 	struct task_struct	*owner;
-#ifdef CONFIG_DEBUG_RT_MUTEXES
 	int			save_state;
-	const char		*name, *file;
-	int			line;
-	void			*magic;
-#endif
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 	struct lockdep_map	dep_map;
 #endif
@ include/linux/rtmutex.h:51 @ struct hrtimer_sleeper;
  extern int rt_mutex_debug_check_no_locks_freed(const void *from,
 						unsigned long len);
  extern void rt_mutex_debug_check_no_locks_held(struct task_struct *task);
+ extern void rt_mutex_debug_task_free(struct task_struct *tsk);
 #else
  static inline int rt_mutex_debug_check_no_locks_freed(const void *from,
 						       unsigned long len)
@ include/linux/rtmutex.h:59 @ struct hrtimer_sleeper;
 	return 0;
  }
 # define rt_mutex_debug_check_no_locks_held(task)	do { } while (0)
+# define rt_mutex_debug_task_free(t)			do { } while (0)
 #endif
 
-#ifdef CONFIG_DEBUG_RT_MUTEXES
-# define __DEBUG_RT_MUTEX_INITIALIZER(mutexname) \
-	, .name = #mutexname, .file = __FILE__, .line = __LINE__
-
-# define rt_mutex_init(mutex) \
+#define rt_mutex_init(mutex) \
 do { \
 	static struct lock_class_key __key; \
 	__rt_mutex_init(mutex, __func__, &__key); \
 } while (0)
 
- extern void rt_mutex_debug_task_free(struct task_struct *tsk);
-#else
-# define __DEBUG_RT_MUTEX_INITIALIZER(mutexname)
-# define rt_mutex_init(mutex)			__rt_mutex_init(mutex, NULL, NULL)
-# define rt_mutex_debug_task_free(t)			do { } while (0)
-#endif
-
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 #define __DEP_MAP_RT_MUTEX_INITIALIZER(mutexname) \
 	, .dep_map = { .name = #mutexname }
@ include/linux/rtmutex.h:75 @ do { \
 #define __DEP_MAP_RT_MUTEX_INITIALIZER(mutexname)
 #endif
 
-#define __RT_MUTEX_INITIALIZER(mutexname) \
-	{ .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(mutexname.wait_lock) \
+#define __RT_MUTEX_INITIALIZER_PLAIN(mutexname) \
+	  .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(mutexname.wait_lock) \
 	, .waiters = RB_ROOT_CACHED \
 	, .owner = NULL \
-	__DEBUG_RT_MUTEX_INITIALIZER(mutexname) \
-	__DEP_MAP_RT_MUTEX_INITIALIZER(mutexname)}
+	__DEP_MAP_RT_MUTEX_INITIALIZER(mutexname)
+
+#define __RT_MUTEX_INITIALIZER(mutexname) \
+	{ __RT_MUTEX_INITIALIZER_PLAIN(mutexname) \
+	, .save_state = 0 }
+
+#define __RT_MUTEX_INITIALIZER_SAVE_STATE(mutexname) \
+	{ __RT_MUTEX_INITIALIZER_PLAIN(mutexname)    \
+	, .save_state = 1 }
 
 #define DEFINE_RT_MUTEX(mutexname) \
 	struct rt_mutex mutexname = __RT_MUTEX_INITIALIZER(mutexname)
@ include/linux/rtmutex.h:115 @ extern void rt_mutex_lock(struct rt_mutex *lock);
 #endif
 
 extern int rt_mutex_lock_interruptible(struct rt_mutex *lock);
-extern int rt_mutex_timed_lock(struct rt_mutex *lock,
-			       struct hrtimer_sleeper *timeout);
-
 extern int rt_mutex_trylock(struct rt_mutex *lock);
 
 extern void rt_mutex_unlock(struct rt_mutex *lock);
@ include/linux/rwlock_rt.h:4 @
+// SPDX-License-Identifier: GPL-2.0-only
+#ifndef __LINUX_RWLOCK_RT_H
+#define __LINUX_RWLOCK_RT_H
+
+#ifndef __LINUX_SPINLOCK_H
+#error Do not include directly. Use spinlock.h
+#endif
+
+extern void __lockfunc rt_write_lock(rwlock_t *rwlock);
+extern void __lockfunc rt_read_lock(rwlock_t *rwlock);
+extern int __lockfunc rt_write_trylock(rwlock_t *rwlock);
+extern int __lockfunc rt_read_trylock(rwlock_t *rwlock);
+extern void __lockfunc rt_write_unlock(rwlock_t *rwlock);
+extern void __lockfunc rt_read_unlock(rwlock_t *rwlock);
+extern int __lockfunc rt_read_can_lock(rwlock_t *rwlock);
+extern int __lockfunc rt_write_can_lock(rwlock_t *rwlock);
+extern void __rt_rwlock_init(rwlock_t *rwlock, char *name, struct lock_class_key *key);
+
+#define read_can_lock(rwlock)		rt_read_can_lock(rwlock)
+#define write_can_lock(rwlock)		rt_write_can_lock(rwlock)
+
+#define read_trylock(lock)	__cond_lock(lock, rt_read_trylock(lock))
+#define write_trylock(lock)	__cond_lock(lock, rt_write_trylock(lock))
+
+static inline int __write_trylock_rt_irqsave(rwlock_t *lock, unsigned long *flags)
+{
+	*flags = 0;
+	return rt_write_trylock(lock);
+}
+
+#define write_trylock_irqsave(lock, flags)		\
+	__cond_lock(lock, __write_trylock_rt_irqsave(lock, &(flags)))
+
+#define read_lock_irqsave(lock, flags)			\
+	do {						\
+		typecheck(unsigned long, flags);	\
+		rt_read_lock(lock);			\
+		flags = 0;				\
+	} while (0)
+
+#define write_lock_irqsave(lock, flags)			\
+	do {						\
+		typecheck(unsigned long, flags);	\
+		rt_write_lock(lock);			\
+		flags = 0;				\
+	} while (0)
+
+#define read_lock(lock)		rt_read_lock(lock)
+
+#define read_lock_bh(lock)				\
+	do {						\
+		local_bh_disable();			\
+		rt_read_lock(lock);			\
+	} while (0)
+
+#define read_lock_irq(lock)	read_lock(lock)
+
+#define write_lock(lock)	rt_write_lock(lock)
+
+#define write_lock_bh(lock)				\
+	do {						\
+		local_bh_disable();			\
+		rt_write_lock(lock);			\
+	} while (0)
+
+#define write_lock_irq(lock)	write_lock(lock)
+
+#define read_unlock(lock)	rt_read_unlock(lock)
+
+#define read_unlock_bh(lock)				\
+	do {						\
+		rt_read_unlock(lock);			\
+		local_bh_enable();			\
+	} while (0)
+
+#define read_unlock_irq(lock)	read_unlock(lock)
+
+#define write_unlock(lock)	rt_write_unlock(lock)
+
+#define write_unlock_bh(lock)				\
+	do {						\
+		rt_write_unlock(lock);			\
+		local_bh_enable();			\
+	} while (0)
+
+#define write_unlock_irq(lock)	write_unlock(lock)
+
+#define read_unlock_irqrestore(lock, flags)		\
+	do {						\
+		typecheck(unsigned long, flags);	\
+		(void) flags;				\
+		rt_read_unlock(lock);			\
+	} while (0)
+
+#define write_unlock_irqrestore(lock, flags) \
+	do {						\
+		typecheck(unsigned long, flags);	\
+		(void) flags;				\
+		rt_write_unlock(lock);			\
+	} while (0)
+
+#define rwlock_init(rwl)				\
+do {							\
+	static struct lock_class_key __key;		\
+							\
+	__rt_rwlock_init(rwl, #rwl, &__key);		\
+} while (0)
+
+#endif
@ include/linux/rwlock_types.h:4 @
 #ifndef __LINUX_RWLOCK_TYPES_H
 #define __LINUX_RWLOCK_TYPES_H
 
+#if !defined(__LINUX_SPINLOCK_TYPES_H)
+# error "Do not include directly, include spinlock_types.h"
+#endif
+
 /*
  * include/linux/rwlock_types.h - generic rwlock type definitions
  *				  and initializers
@ include/linux/rwlock_types_rt.h:4 @
+// SPDX-License-Identifier: GPL-2.0-only
+#ifndef __LINUX_RWLOCK_TYPES_RT_H
+#define __LINUX_RWLOCK_TYPES_RT_H
+
+#ifndef __LINUX_SPINLOCK_TYPES_H
+#error "Do not include directly. Include spinlock_types.h instead"
+#endif
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define RW_DEP_MAP_INIT(lockname)	.dep_map = { .name = #lockname }
+#else
+# define RW_DEP_MAP_INIT(lockname)
+#endif
+
+typedef struct rt_rw_lock rwlock_t;
+
+#define __RW_LOCK_UNLOCKED(name) __RWLOCK_RT_INITIALIZER(name)
+
+#define DEFINE_RWLOCK(name) \
+	rwlock_t name = __RW_LOCK_UNLOCKED(name)
+
+/*
+ * A reader biased implementation primarily for CPU pinning.
+ *
+ * Can be selected as general replacement for the single reader RT rwlock
+ * variant
+ */
+struct rt_rw_lock {
+	struct rt_mutex		rtmutex;
+	atomic_t		readers;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+	struct lockdep_map	dep_map;
+#endif
+};
+
+#define READER_BIAS	(1U << 31)
+#define WRITER_BIAS	(1U << 30)
+
+#define __RWLOCK_RT_INITIALIZER(name)					\
+{									\
+	.readers = ATOMIC_INIT(READER_BIAS),				\
+	.rtmutex = __RT_MUTEX_INITIALIZER_SAVE_STATE(name.rtmutex),	\
+	RW_DEP_MAP_INIT(name)						\
+}
+
+void __rwlock_biased_rt_init(struct rt_rw_lock *lock, const char *name,
+			     struct lock_class_key *key);
+
+#define rwlock_biased_rt_init(rwlock)					\
+	do {								\
+		static struct lock_class_key __key;			\
+									\
+		__rwlock_biased_rt_init((rwlock), #rwlock, &__key);	\
+	} while (0)
+
+#endif
@ include/linux/rwsem-rt.h:4 @
+// SPDX-License-Identifier: GPL-2.0-only
+#ifndef _LINUX_RWSEM_RT_H
+#define _LINUX_RWSEM_RT_H
+
+#ifndef _LINUX_RWSEM_H
+#error "Include rwsem.h"
+#endif
+
+#include <linux/rtmutex.h>
+#include <linux/swait.h>
+
+#define READER_BIAS		(1U << 31)
+#define WRITER_BIAS		(1U << 30)
+
+struct rw_semaphore {
+	atomic_t		readers;
+	struct rt_mutex		rtmutex;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+	struct lockdep_map	dep_map;
+#endif
+};
+
+#define __RWSEM_INITIALIZER(name)				\
+{								\
+	.readers = ATOMIC_INIT(READER_BIAS),			\
+	.rtmutex = __RT_MUTEX_INITIALIZER(name.rtmutex),	\
+	RW_DEP_MAP_INIT(name)					\
+}
+
+#define DECLARE_RWSEM(lockname) \
+	struct rw_semaphore lockname = __RWSEM_INITIALIZER(lockname)
+
+extern void  __rwsem_init(struct rw_semaphore *rwsem, const char *name,
+			  struct lock_class_key *key);
+
+#define __init_rwsem(sem, name, key)			\
+do {							\
+		rt_mutex_init(&(sem)->rtmutex);		\
+		__rwsem_init((sem), (name), (key));	\
+} while (0)
+
+#define init_rwsem(sem)					\
+do {							\
+	static struct lock_class_key __key;		\
+							\
+	__init_rwsem((sem), #sem, &__key);		\
+} while (0)
+
+static inline int rwsem_is_locked(struct rw_semaphore *sem)
+{
+	return atomic_read(&sem->readers) != READER_BIAS;
+}
+
+static inline int rwsem_is_contended(struct rw_semaphore *sem)
+{
+	return atomic_read(&sem->readers) > 0;
+}
+
+extern void __down_read(struct rw_semaphore *sem);
+extern int __down_read_interruptible(struct rw_semaphore *sem);
+extern int __down_read_killable(struct rw_semaphore *sem);
+extern int __down_read_trylock(struct rw_semaphore *sem);
+extern void __down_write(struct rw_semaphore *sem);
+extern int __must_check __down_write_killable(struct rw_semaphore *sem);
+extern int __down_write_trylock(struct rw_semaphore *sem);
+extern void __up_read(struct rw_semaphore *sem);
+extern void __up_write(struct rw_semaphore *sem);
+extern void __downgrade_write(struct rw_semaphore *sem);
+
+#endif
@ include/linux/rwsem.h:19 @
 #include <linux/spinlock.h>
 #include <linux/atomic.h>
 #include <linux/err.h>
+
+#ifdef CONFIG_PREEMPT_RT
+#include <linux/rwsem-rt.h>
+#else /* PREEMPT_RT */
+
 #ifdef CONFIG_RWSEM_SPIN_ON_OWNER
 #include <linux/osq_lock.h>
 #endif
@ include/linux/rwsem.h:127 @ static inline int rwsem_is_contended(struct rw_semaphore *sem)
 	return !list_empty(&sem->wait_list);
 }
 
+#endif /* !PREEMPT_RT */
+
+/*
+ * The functions below are the same for all rwsem implementations including
+ * the RT specific variant.
+ */
+
 /*
  * lock for reading
  */
@ include/linux/sched.h:37 @
 #include <linux/rseq.h>
 #include <linux/seqlock.h>
 #include <linux/kcsan.h>
+#include <asm/kmap_size.h>
 
 /* task_struct member predeclarations (sorted alphabetically): */
 struct audit_context;
@ include/linux/sched.h:115 @ struct io_uring_task;
 					 __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \
 					 TASK_PARKED)
 
-#define task_is_traced(task)		((task->state & __TASK_TRACED) != 0)
-
 #define task_is_stopped(task)		((task->state & __TASK_STOPPED) != 0)
 
-#define task_is_stopped_or_traced(task)	((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
-
 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
 
 /*
@ include/linux/sched.h:140 @ struct io_uring_task;
 		smp_store_mb(current->state, (state_value));	\
 	} while (0)
 
+#define __set_current_state_no_track(state_value)		\
+	current->state = (state_value);
+
 #define set_special_state(state_value)					\
 	do {								\
 		unsigned long flags; /* may shadow */			\
@ include/linux/sched.h:196 @ struct io_uring_task;
 #define set_current_state(state_value)					\
 	smp_store_mb(current->state, (state_value))
 
+#define __set_current_state_no_track(state_value)	\
+	__set_current_state(state_value)
+
 /*
  * set_special_state() should be used for those states when the blocking task
  * can not use the regular condition based wait-loop. In that case we must
@ include/linux/sched.h:651 @ struct wake_q_node {
 	struct wake_q_node *next;
 };
 
+struct kmap_ctrl {
+#ifdef CONFIG_KMAP_LOCAL
+	int				idx;
+	pte_t				pteval[KM_MAX_IDX];
+#endif
+};
+
 struct task_struct {
 #ifdef CONFIG_THREAD_INFO_IN_TASK
 	/*
@ include/linux/sched.h:668 @ struct task_struct {
 #endif
 	/* -1 unrunnable, 0 runnable, >0 stopped: */
 	volatile long			state;
+	/* saved state for "spinlock sleepers" */
+	volatile long			saved_state;
 
 	/*
 	 * This begins the randomizable portion of task_struct. Only
@ include/linux/sched.h:745 @ struct task_struct {
 	int				nr_cpus_allowed;
 	const cpumask_t			*cpus_ptr;
 	cpumask_t			cpus_mask;
+	void				*migration_pending;
+#ifdef CONFIG_SMP
+	unsigned short			migration_disabled;
+#endif
+	unsigned short			migration_flags;
 
 #ifdef CONFIG_PREEMPT_RCU
 	int				rcu_read_lock_nesting;
@ include/linux/sched.h:996 @ struct task_struct {
 	/* Signal handlers: */
 	struct signal_struct		*signal;
 	struct sighand_struct __rcu		*sighand;
+	struct sigqueue			*sigqueue_cache;
 	sigset_t			blocked;
 	sigset_t			real_blocked;
 	/* Restored if set_restore_sigmask() was used: */
 	sigset_t			saved_sigmask;
 	struct sigpending		pending;
+#ifdef CONFIG_PREEMPT_RT
+	/* TODO: move me into ->restart_block ? */
+	struct				kernel_siginfo forced_info;
+#endif
 	unsigned long			sas_ss_sp;
 	size_t				sas_ss_size;
 	unsigned int			sas_ss_flags;
@ include/linux/sched.h:1032 @ struct task_struct {
 	raw_spinlock_t			pi_lock;
 
 	struct wake_q_node		wake_q;
+	struct wake_q_node		wake_q_sleeper;
 
 #ifdef CONFIG_RT_MUTEXES
 	/* PI waiters blocked on a rt_mutex held by this task: */
@ include/linux/sched.h:1060 @ struct task_struct {
 	int				softirq_context;
 	int				irq_config;
 #endif
+#ifdef CONFIG_PREEMPT_RT
+	int				softirq_disable_cnt;
+#endif
 
 #ifdef CONFIG_LOCKDEP
 # define MAX_LOCK_DEPTH			48UL
@ include/linux/sched.h:1348 @ struct task_struct {
 	unsigned int			sequential_io;
 	unsigned int			sequential_io_avg;
 #endif
+	struct kmap_ctrl		kmap_ctrl;
 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
 	unsigned long			task_state_change;
 #endif
@ include/linux/sched.h:1794 @ extern struct task_struct *find_get_task_by_vpid(pid_t nr);
 
 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
 extern int wake_up_process(struct task_struct *tsk);
+extern int wake_up_lock_sleeper(struct task_struct *tsk);
 extern void wake_up_new_task(struct task_struct *tsk);
 
 #ifdef CONFIG_SMP
@ include/linux/sched.h:1885 @ static inline int test_tsk_need_resched(struct task_struct *tsk)
 	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
 }
 
+#ifdef CONFIG_PREEMPT_LAZY
+static inline void set_tsk_need_resched_lazy(struct task_struct *tsk)
+{
+	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED_LAZY);
+}
+
+static inline void clear_tsk_need_resched_lazy(struct task_struct *tsk)
+{
+	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED_LAZY);
+}
+
+static inline int test_tsk_need_resched_lazy(struct task_struct *tsk)
+{
+	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED_LAZY));
+}
+
+static inline int need_resched_lazy(void)
+{
+	return test_thread_flag(TIF_NEED_RESCHED_LAZY);
+}
+
+static inline int need_resched_now(void)
+{
+	return test_thread_flag(TIF_NEED_RESCHED);
+}
+
+#else
+static inline void clear_tsk_need_resched_lazy(struct task_struct *tsk) { }
+static inline int need_resched_lazy(void) { return 0; }
+
+static inline int need_resched_now(void)
+{
+	return test_thread_flag(TIF_NEED_RESCHED);
+}
+
+#endif
+
+
+static inline bool __task_is_stopped_or_traced(struct task_struct *task)
+{
+	if (task->state & (__TASK_STOPPED | __TASK_TRACED))
+		return true;
+#ifdef CONFIG_PREEMPT_RT
+	if (task->saved_state & (__TASK_STOPPED | __TASK_TRACED))
+		return true;
+#endif
+	return false;
+}
+
+static inline bool task_is_stopped_or_traced(struct task_struct *task)
+{
+	bool traced_stopped;
+
+#ifdef CONFIG_PREEMPT_RT
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&task->pi_lock, flags);
+	traced_stopped = __task_is_stopped_or_traced(task);
+	raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+#else
+	traced_stopped = __task_is_stopped_or_traced(task);
+#endif
+	return traced_stopped;
+}
+
+static inline bool task_is_traced(struct task_struct *task)
+{
+	bool traced = false;
+
+	if (task->state & __TASK_TRACED)
+		return true;
+#ifdef CONFIG_PREEMPT_RT
+	/* in case the task is sleeping on tasklist_lock */
+	raw_spin_lock_irq(&task->pi_lock);
+	if (task->state & __TASK_TRACED)
+		traced = true;
+	else if (task->saved_state & __TASK_TRACED)
+		traced = true;
+	raw_spin_unlock_irq(&task->pi_lock);
+#endif
+	return traced;
+}
+
 /*
  * cond_resched() and cond_resched_lock(): latency reduction via
  * explicit rescheduling in places that are safe. The return
@ include/linux/sched/hotplug.h:14 @ extern int sched_cpu_activate(unsigned int cpu);
 extern int sched_cpu_deactivate(unsigned int cpu);
 
 #ifdef CONFIG_HOTPLUG_CPU
+extern int sched_cpu_wait_empty(unsigned int cpu);
 extern int sched_cpu_dying(unsigned int cpu);
 #else
+# define sched_cpu_wait_empty	NULL
 # define sched_cpu_dying	NULL
 #endif
 
@ include/linux/sched/mm.h:52 @ static inline void mmdrop(struct mm_struct *mm)
 		__mmdrop(mm);
 }
 
+#ifdef CONFIG_PREEMPT_RT
+extern void __mmdrop_delayed(struct rcu_head *rhp);
+static inline void mmdrop_delayed(struct mm_struct *mm)
+{
+	if (atomic_dec_and_test(&mm->mm_count))
+		call_rcu(&mm->delayed_drop, __mmdrop_delayed);
+}
+#else
+# define mmdrop_delayed(mm)    mmdrop(mm)
+#endif
+
 /**
  * mmget() - Pin the address space associated with a &struct mm_struct.
  * @mm: The address space to pin.
@ include/linux/sched/rt.h:42 @ static inline struct task_struct *rt_mutex_get_top_task(struct task_struct *p)
 }
 extern void rt_mutex_setprio(struct task_struct *p, struct task_struct *pi_task);
 extern void rt_mutex_adjust_pi(struct task_struct *p);
-static inline bool tsk_is_pi_blocked(struct task_struct *tsk)
-{
-	return tsk->pi_blocked_on != NULL;
-}
 #else
 static inline struct task_struct *rt_mutex_get_top_task(struct task_struct *task)
 {
 	return NULL;
 }
 # define rt_mutex_adjust_pi(p)		do { } while (0)
-static inline bool tsk_is_pi_blocked(struct task_struct *tsk)
-{
-	return false;
-}
 #endif
 
 extern void normalize_rt_tasks(void);
@ include/linux/sched/wake_q.h:61 @ static inline bool wake_q_empty(struct wake_q_head *head)
 
 extern void wake_q_add(struct wake_q_head *head, struct task_struct *task);
 extern void wake_q_add_safe(struct wake_q_head *head, struct task_struct *task);
-extern void wake_up_q(struct wake_q_head *head);
+extern void wake_q_add_sleeper(struct wake_q_head *head, struct task_struct *task);
+extern void __wake_up_q(struct wake_q_head *head, bool sleeper);
+
+static inline void wake_up_q(struct wake_q_head *head)
+{
+	__wake_up_q(head, false);
+}
+
+static inline void wake_up_q_sleeper(struct wake_q_head *head)
+{
+	__wake_up_q(head, true);
+}
 
 #endif /* _LINUX_SCHED_WAKE_Q_H */
@ include/linux/serial_8250.h:10 @
 #ifndef _LINUX_SERIAL_8250_H
 #define _LINUX_SERIAL_8250_H
 
+#include <linux/atomic.h>
 #include <linux/serial_core.h>
 #include <linux/serial_reg.h>
 #include <linux/platform_device.h>
@ include/linux/serial_8250.h:129 @ struct uart_8250_port {
 #define MSR_SAVE_FLAGS UART_MSR_ANY_DELTA
 	unsigned char		msr_saved_flags;
 
+	atomic_t		console_printing;
+
 	struct uart_8250_dma	*dma;
 	const struct uart_8250_ops *ops;
 
@ include/linux/serial_8250.h:186 @ void serial8250_init_port(struct uart_8250_port *up);
 void serial8250_set_defaults(struct uart_8250_port *up);
 void serial8250_console_write(struct uart_8250_port *up, const char *s,
 			      unsigned int count);
+void serial8250_console_write_atomic(struct uart_8250_port *up, const char *s,
+				     unsigned int count);
 int serial8250_console_setup(struct uart_port *port, char *options, bool probe);
 int serial8250_console_exit(struct uart_port *port);
 
@ include/linux/shmem_fs.h:34 @ struct shmem_sb_info {
 	struct percpu_counter used_blocks;  /* How many are allocated */
 	unsigned long max_inodes;   /* How many inodes are allowed */
 	unsigned long free_inodes;  /* How many are left for allocation */
-	spinlock_t stat_lock;	    /* Serialize shmem_sb_info changes */
+	raw_spinlock_t stat_lock;   /* Serialize shmem_sb_info changes */
 	umode_t mode;		    /* Mount mode for root directory */
 	unsigned char huge;	    /* Whether to try for hugepages */
 	kuid_t uid;		    /* Mount uid for root directory */
@ include/linux/signal.h:268 @ static inline void init_sigpending(struct sigpending *sig)
 }
 
 extern void flush_sigqueue(struct sigpending *queue);
+extern void flush_task_sigqueue(struct task_struct *tsk);
 
 /* Test if 'sig' is valid signal. Use this instead of testing _NSIG directly */
 static inline int valid_signal(unsigned long sig)
@ include/linux/skbuff.h:298 @ struct sk_buff_head {
 
 	__u32		qlen;
 	spinlock_t	lock;
+	raw_spinlock_t	raw_lock;
 };
 
 struct sk_buff;
@ include/linux/skbuff.h:1888 @ static inline void skb_queue_head_init(struct sk_buff_head *list)
 	__skb_queue_head_init(list);
 }
 
+static inline void skb_queue_head_init_raw(struct sk_buff_head *list)
+{
+	raw_spin_lock_init(&list->raw_lock);
+	__skb_queue_head_init(list);
+}
+
 static inline void skb_queue_head_init_class(struct sk_buff_head *list,
 		struct lock_class_key *class)
 {
@ include/linux/smp.h:242 @ static inline int get_boot_cpu_id(void)
 #define get_cpu()		({ preempt_disable(); __smp_processor_id(); })
 #define put_cpu()		preempt_enable()
 
+#define get_cpu_light()		({ migrate_disable(); __smp_processor_id(); })
+#define put_cpu_light()		migrate_enable()
+
 /*
  * Callback to arch code if there's nosmp or maxcpus=0 on the
  * boot command line:
@ include/linux/spinlock.h:312 @ static inline void do_raw_spin_unlock(raw_spinlock_t *lock) __releases(lock)
 })
 
 /* Include rwlock functions */
-#include <linux/rwlock.h>
+#ifdef CONFIG_PREEMPT_RT
+# include <linux/rwlock_rt.h>
+#else
+# include <linux/rwlock.h>
+#endif
 
 /*
  * Pull the _spin_*()/_read_*()/_write_*() functions/declarations:
@ include/linux/spinlock.h:327 @ static inline void do_raw_spin_unlock(raw_spinlock_t *lock) __releases(lock)
 # include <linux/spinlock_api_up.h>
 #endif
 
+#ifdef CONFIG_PREEMPT_RT
+# include <linux/spinlock_rt.h>
+#else /* PREEMPT_RT */
+
 /*
  * Map the spin_lock functions to the raw variants for PREEMPT_RT=n
  */
@ include/linux/spinlock.h:465 @ static __always_inline int spin_is_contended(spinlock_t *lock)
 
 #define assert_spin_locked(lock)	assert_raw_spin_locked(&(lock)->rlock)
 
+#endif /* !PREEMPT_RT */
+
 /*
  * Pull the atomic_t declaration:
  * (asm-mips/atomic.h needs above definitions)
@ include/linux/spinlock_api_smp.h:190 @ static inline int __raw_spin_trylock_bh(raw_spinlock_t *lock)
 	return 0;
 }
 
-#include <linux/rwlock_api_smp.h>
+#ifndef CONFIG_PREEMPT_RT
+# include <linux/rwlock_api_smp.h>
+#endif
 
 #endif /* __LINUX_SPINLOCK_API_SMP_H */
@ include/linux/spinlock_rt.h:4 @
+// SPDX-License-Identifier: GPL-2.0-only
+#ifndef __LINUX_SPINLOCK_RT_H
+#define __LINUX_SPINLOCK_RT_H
+
+#ifndef __LINUX_SPINLOCK_H
+#error Do not include directly. Use spinlock.h
+#endif
+
+#include <linux/bug.h>
+
+extern void
+__rt_spin_lock_init(spinlock_t *lock, const char *name, struct lock_class_key *key);
+
+#define spin_lock_init(slock)				\
+do {							\
+	static struct lock_class_key __key;		\
+							\
+	rt_mutex_init(&(slock)->lock);			\
+	__rt_spin_lock_init(slock, #slock, &__key);	\
+} while (0)
+
+extern void __lockfunc rt_spin_lock(spinlock_t *lock);
+extern void __lockfunc rt_spin_lock_nested(spinlock_t *lock, int subclass);
+extern void __lockfunc rt_spin_lock_nest_lock(spinlock_t *lock, struct lockdep_map *nest_lock);
+extern void __lockfunc rt_spin_unlock(spinlock_t *lock);
+extern void __lockfunc rt_spin_lock_unlock(spinlock_t *lock);
+extern int __lockfunc rt_spin_trylock_irqsave(spinlock_t *lock, unsigned long *flags);
+extern int __lockfunc rt_spin_trylock_bh(spinlock_t *lock);
+extern int __lockfunc rt_spin_trylock(spinlock_t *lock);
+extern int atomic_dec_and_spin_lock(atomic_t *atomic, spinlock_t *lock);
+
+/*
+ * lockdep-less calls, for derived types like rwlock:
+ * (for trylock they can use rt_mutex_trylock() directly.
+ * Migrate disable handling must be done at the call site.
+ */
+extern void __lockfunc __rt_spin_lock(struct rt_mutex *lock);
+extern void __lockfunc __rt_spin_trylock(struct rt_mutex *lock);
+extern void __lockfunc __rt_spin_unlock(struct rt_mutex *lock);
+
+#define spin_lock(lock)			rt_spin_lock(lock)
+
+#define spin_lock_bh(lock)			\
+	do {					\
+		local_bh_disable();		\
+		rt_spin_lock(lock);		\
+	} while (0)
+
+#define spin_lock_irq(lock)		spin_lock(lock)
+
+#define spin_do_trylock(lock)		__cond_lock(lock, rt_spin_trylock(lock))
+
+#define spin_trylock(lock)			\
+({						\
+	int __locked;				\
+	__locked = spin_do_trylock(lock);	\
+	__locked;				\
+})
+
+#ifdef CONFIG_LOCKDEP
+# define spin_lock_nested(lock, subclass)		\
+	do {						\
+		rt_spin_lock_nested(lock, subclass);	\
+	} while (0)
+
+#define spin_lock_bh_nested(lock, subclass)		\
+	do {						\
+		local_bh_disable();			\
+		rt_spin_lock_nested(lock, subclass);	\
+	} while (0)
+
+# define spin_lock_nest_lock(lock, subclass)		\
+	do {                                                           \
+		typecheck(struct lockdep_map *, &(subclass)->dep_map);	\
+		rt_spin_lock_nest_lock(lock, &(subclass)->dep_map);	\
+	} while (0)
+
+# define spin_lock_irqsave_nested(lock, flags, subclass) \
+	do {						 \
+		typecheck(unsigned long, flags);	 \
+		flags = 0;				 \
+		rt_spin_lock_nested(lock, subclass);	 \
+	} while (0)
+#else
+# define spin_lock_nested(lock, subclass)	spin_lock(((void)(subclass), (lock)))
+# define spin_lock_nest_lock(lock, subclass)	spin_lock(((void)(subclass), (lock)))
+# define spin_lock_bh_nested(lock, subclass)	spin_lock_bh(((void)(subclass), (lock)))
+
+# define spin_lock_irqsave_nested(lock, flags, subclass) \
+	do {						 \
+		typecheck(unsigned long, flags);	 \
+		flags = 0;				 \
+		spin_lock(((void)(subclass), (lock)));	 \
+	} while (0)
+#endif
+
+#define spin_lock_irqsave(lock, flags)			 \
+	do {						 \
+		typecheck(unsigned long, flags);	 \
+		flags = 0;				 \
+		spin_lock(lock);			 \
+	} while (0)
+
+#define spin_unlock(lock)			rt_spin_unlock(lock)
+
+#define spin_unlock_bh(lock)				\
+	do {						\
+		rt_spin_unlock(lock);			\
+		local_bh_enable();			\
+	} while (0)
+
+#define spin_unlock_irq(lock)		spin_unlock(lock)
+
+#define spin_unlock_irqrestore(lock, flags)		\
+	do {						\
+		typecheck(unsigned long, flags);	\
+		(void) flags;				\
+		spin_unlock(lock);			\
+	} while (0)
+
+#define spin_trylock_bh(lock)	__cond_lock(lock, rt_spin_trylock_bh(lock))
+#define spin_trylock_irq(lock)	spin_trylock(lock)
+
+#define spin_trylock_irqsave(lock, flags)		\
+({							\
+	int __locked;					\
+							\
+	typecheck(unsigned long, flags);		\
+	flags = 0;					\
+	__locked = spin_trylock(lock);			\
+	__locked;					\
+})
+
+#ifdef CONFIG_GENERIC_LOCKBREAK
+# define spin_is_contended(lock)	((lock)->break_lock)
+#else
+# define spin_is_contended(lock)	(((void)(lock), 0))
+#endif
+
+static inline int spin_can_lock(spinlock_t *lock)
+{
+	return !rt_mutex_is_locked(&lock->lock);
+}
+
+static inline int spin_is_locked(spinlock_t *lock)
+{
+	return rt_mutex_is_locked(&lock->lock);
+}
+
+static inline void assert_spin_locked(spinlock_t *lock)
+{
+	BUG_ON(!spin_is_locked(lock));
+}
+
+#endif
@ include/linux/spinlock_types.h:12 @
  * Released under the General Public License (GPL).
  */
 
-#if defined(CONFIG_SMP)
-# include <asm/spinlock_types.h>
-#else
-# include <linux/spinlock_types_up.h>
-#endif
-
-#include <linux/lockdep_types.h>
-
-typedef struct raw_spinlock {
-	arch_spinlock_t raw_lock;
-#ifdef CONFIG_DEBUG_SPINLOCK
-	unsigned int magic, owner_cpu;
-	void *owner;
-#endif
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-	struct lockdep_map dep_map;
-#endif
-} raw_spinlock_t;
-
-#define SPINLOCK_MAGIC		0xdead4ead
-
-#define SPINLOCK_OWNER_INIT	((void *)-1L)
-
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-# define RAW_SPIN_DEP_MAP_INIT(lockname)		\
-	.dep_map = {					\
-		.name = #lockname,			\
-		.wait_type_inner = LD_WAIT_SPIN,	\
-	}
-# define SPIN_DEP_MAP_INIT(lockname)			\
-	.dep_map = {					\
-		.name = #lockname,			\
-		.wait_type_inner = LD_WAIT_CONFIG,	\
-	}
-#else
-# define RAW_SPIN_DEP_MAP_INIT(lockname)
-# define SPIN_DEP_MAP_INIT(lockname)
-#endif
+#include <linux/spinlock_types_raw.h>
 
-#ifdef CONFIG_DEBUG_SPINLOCK
-# define SPIN_DEBUG_INIT(lockname)		\
-	.magic = SPINLOCK_MAGIC,		\
-	.owner_cpu = -1,			\
-	.owner = SPINLOCK_OWNER_INIT,
+#ifndef CONFIG_PREEMPT_RT
+# include <linux/spinlock_types_nort.h>
+# include <linux/rwlock_types.h>
 #else
-# define SPIN_DEBUG_INIT(lockname)
+# include <linux/rtmutex.h>
+# include <linux/spinlock_types_rt.h>
+# include <linux/rwlock_types_rt.h>
 #endif
 
-#define __RAW_SPIN_LOCK_INITIALIZER(lockname)	\
-	{					\
-	.raw_lock = __ARCH_SPIN_LOCK_UNLOCKED,	\
-	SPIN_DEBUG_INIT(lockname)		\
-	RAW_SPIN_DEP_MAP_INIT(lockname) }
-
-#define __RAW_SPIN_LOCK_UNLOCKED(lockname)	\
-	(raw_spinlock_t) __RAW_SPIN_LOCK_INITIALIZER(lockname)
-
-#define DEFINE_RAW_SPINLOCK(x)	raw_spinlock_t x = __RAW_SPIN_LOCK_UNLOCKED(x)
-
-typedef struct spinlock {
-	union {
-		struct raw_spinlock rlock;
-
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-# define LOCK_PADSIZE (offsetof(struct raw_spinlock, dep_map))
-		struct {
-			u8 __padding[LOCK_PADSIZE];
-			struct lockdep_map dep_map;
-		};
-#endif
-	};
-} spinlock_t;
-
-#define ___SPIN_LOCK_INITIALIZER(lockname)	\
-	{					\
-	.raw_lock = __ARCH_SPIN_LOCK_UNLOCKED,	\
-	SPIN_DEBUG_INIT(lockname)		\
-	SPIN_DEP_MAP_INIT(lockname) }
-
-#define __SPIN_LOCK_INITIALIZER(lockname) \
-	{ { .rlock = ___SPIN_LOCK_INITIALIZER(lockname) } }
-
-#define __SPIN_LOCK_UNLOCKED(lockname) \
-	(spinlock_t) __SPIN_LOCK_INITIALIZER(lockname)
-
-#define DEFINE_SPINLOCK(x)	spinlock_t x = __SPIN_LOCK_UNLOCKED(x)
-
-#include <linux/rwlock_types.h>
-
 #endif /* __LINUX_SPINLOCK_TYPES_H */
@ include/linux/spinlock_types_nort.h:4 @
+#ifndef __LINUX_SPINLOCK_TYPES_NORT_H
+#define __LINUX_SPINLOCK_TYPES_NORT_H
+
+#ifndef __LINUX_SPINLOCK_TYPES_H
+#error "Do not include directly. Include spinlock_types.h instead"
+#endif
+
+/*
+ * The non RT version maps spinlocks to raw_spinlocks
+ */
+typedef struct spinlock {
+	union {
+		struct raw_spinlock rlock;
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define LOCK_PADSIZE (offsetof(struct raw_spinlock, dep_map))
+		struct {
+			u8 __padding[LOCK_PADSIZE];
+			struct lockdep_map dep_map;
+		};
+#endif
+	};
+} spinlock_t;
+
+#define ___SPIN_LOCK_INITIALIZER(lockname)	\
+{						\
+	.raw_lock = __ARCH_SPIN_LOCK_UNLOCKED,	\
+	SPIN_DEBUG_INIT(lockname)		\
+	SPIN_DEP_MAP_INIT(lockname) }
+
+#define __SPIN_LOCK_INITIALIZER(lockname) \
+	{ { .rlock = ___SPIN_LOCK_INITIALIZER(lockname) } }
+
+#define __SPIN_LOCK_UNLOCKED(lockname) \
+	(spinlock_t) __SPIN_LOCK_INITIALIZER(lockname)
+
+#define DEFINE_SPINLOCK(x)	spinlock_t x = __SPIN_LOCK_UNLOCKED(x)
+
+#endif
@ include/linux/spinlock_types_raw.h:4 @
+#ifndef __LINUX_SPINLOCK_TYPES_RAW_H
+#define __LINUX_SPINLOCK_TYPES_RAW_H
+
+#include <linux/types.h>
+
+#if defined(CONFIG_SMP)
+# include <asm/spinlock_types.h>
+#else
+# include <linux/spinlock_types_up.h>
+#endif
+
+#include <linux/lockdep_types.h>
+
+typedef struct raw_spinlock {
+	arch_spinlock_t raw_lock;
+#ifdef CONFIG_DEBUG_SPINLOCK
+	unsigned int magic, owner_cpu;
+	void *owner;
+#endif
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+	struct lockdep_map dep_map;
+#endif
+} raw_spinlock_t;
+
+#define SPINLOCK_MAGIC		0xdead4ead
+
+#define SPINLOCK_OWNER_INIT	((void *)-1L)
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define RAW_SPIN_DEP_MAP_INIT(lockname)		\
+	.dep_map = {					\
+		.name = #lockname,			\
+		.wait_type_inner = LD_WAIT_SPIN,	\
+	}
+# define SPIN_DEP_MAP_INIT(lockname)			\
+	.dep_map = {					\
+		.name = #lockname,			\
+		.wait_type_inner = LD_WAIT_CONFIG,	\
+	}
+#else
+# define RAW_SPIN_DEP_MAP_INIT(lockname)
+# define SPIN_DEP_MAP_INIT(lockname)
+#endif
+
+#ifdef CONFIG_DEBUG_SPINLOCK
+# define SPIN_DEBUG_INIT(lockname)		\
+	.magic = SPINLOCK_MAGIC,		\
+	.owner_cpu = -1,			\
+	.owner = SPINLOCK_OWNER_INIT,
+#else
+# define SPIN_DEBUG_INIT(lockname)
+#endif
+
+#define __RAW_SPIN_LOCK_INITIALIZER(lockname)	\
+{						\
+	.raw_lock = __ARCH_SPIN_LOCK_UNLOCKED,	\
+	SPIN_DEBUG_INIT(lockname)		\
+	RAW_SPIN_DEP_MAP_INIT(lockname) }
+
+#define __RAW_SPIN_LOCK_UNLOCKED(lockname)	\
+	(raw_spinlock_t) __RAW_SPIN_LOCK_INITIALIZER(lockname)
+
+#define DEFINE_RAW_SPINLOCK(x)  raw_spinlock_t x = __RAW_SPIN_LOCK_UNLOCKED(x)
+
+#endif
@ include/linux/spinlock_types_rt.h:4 @
+// SPDX-License-Identifier: GPL-2.0-only
+#ifndef __LINUX_SPINLOCK_TYPES_RT_H
+#define __LINUX_SPINLOCK_TYPES_RT_H
+
+#ifndef __LINUX_SPINLOCK_TYPES_H
+#error "Do not include directly. Include spinlock_types.h instead"
+#endif
+
+#include <linux/cache.h>
+
+/*
+ * PREEMPT_RT: spinlocks - an RT mutex plus lock-break field:
+ */
+typedef struct spinlock {
+	struct rt_mutex		lock;
+	unsigned int		break_lock;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+	struct lockdep_map	dep_map;
+#endif
+} spinlock_t;
+
+#define __RT_SPIN_INITIALIZER(name) \
+	{ \
+	.wait_lock = __RAW_SPIN_LOCK_UNLOCKED(name.wait_lock), \
+	.save_state = 1, \
+	}
+/*
+.wait_list = PLIST_HEAD_INIT_RAW((name).lock.wait_list, (name).lock.wait_lock)
+*/
+
+#define __SPIN_LOCK_UNLOCKED(name)			\
+	{ .lock = __RT_SPIN_INITIALIZER(name.lock),		\
+	  SPIN_DEP_MAP_INIT(name) }
+
+#define DEFINE_SPINLOCK(name) \
+	spinlock_t name = __SPIN_LOCK_UNLOCKED(name)
+
+#endif
@ include/linux/spinlock_types_up.h:4 @
 #ifndef __LINUX_SPINLOCK_TYPES_UP_H
 #define __LINUX_SPINLOCK_TYPES_UP_H
 
-#ifndef __LINUX_SPINLOCK_TYPES_H
+#if !defined(__LINUX_SPINLOCK_TYPES_H) && !defined(__LINUX_RT_MUTEX_H)
 # error "please don't include this file directly"
 #endif
 
@ include/linux/stop_machine.h:27 @ typedef int (*cpu_stop_fn_t)(void *arg);
 struct cpu_stop_work {
 	struct list_head	list;		/* cpu_stopper->works */
 	cpu_stop_fn_t		fn;
+	unsigned long		caller;
 	void			*arg;
 	struct cpu_stop_done	*done;
 };
@ include/linux/stop_machine.h:40 @ void stop_machine_park(int cpu);
 void stop_machine_unpark(int cpu);
 void stop_machine_yield(const struct cpumask *cpumask);
 
+extern void print_stop_info(const char *log_lvl, struct task_struct *task);
+
 #else	/* CONFIG_SMP */
 
 #include <linux/workqueue.h>
@ include/linux/stop_machine.h:86 @ static inline bool stop_one_cpu_nowait(unsigned int cpu,
 	return false;
 }
 
+static inline void print_stop_info(const char *log_lvl, struct task_struct *task) { }
+
 #endif	/* CONFIG_SMP */
 
 /*
@ include/linux/thread_info.h:113 @ static inline int test_ti_thread_flag(struct thread_info *ti, int flag)
 #define test_thread_flag(flag) \
 	test_ti_thread_flag(current_thread_info(), flag)
 
-#define tif_need_resched() test_thread_flag(TIF_NEED_RESCHED)
+#ifdef CONFIG_PREEMPT_LAZY
+#define tif_need_resched()	(test_thread_flag(TIF_NEED_RESCHED) || \
+				 test_thread_flag(TIF_NEED_RESCHED_LAZY))
+#define tif_need_resched_now()	(test_thread_flag(TIF_NEED_RESCHED))
+#define tif_need_resched_lazy()	test_thread_flag(TIF_NEED_RESCHED_LAZY))
+
+#else
+#define tif_need_resched()	test_thread_flag(TIF_NEED_RESCHED)
+#define tif_need_resched_now()	test_thread_flag(TIF_NEED_RESCHED)
+#define tif_need_resched_lazy()	0
+#endif
 
 #ifndef CONFIG_HAVE_ARCH_WITHIN_STACK_FRAMES
 static inline int arch_within_stack_frames(const void * const stack,
@ include/linux/trace_events.h:70 @ struct trace_entry {
 	unsigned char		flags;
 	unsigned char		preempt_count;
 	int			pid;
+	unsigned char		migrate_disable;
+	unsigned char		preempt_lazy_count;
 };
 
 #define TRACE_EVENT_TYPE_MAX						\
@ include/linux/trace_events.h:153 @ enum print_line_t {
 
 enum print_line_t trace_handle_return(struct trace_seq *s);
 
-void tracing_generic_entry_update(struct trace_entry *entry,
-				  unsigned short type,
-				  unsigned long flags,
-				  int pc);
+static inline void tracing_generic_entry_update(struct trace_entry *entry,
+						unsigned short type,
+						unsigned int trace_ctx)
+{
+	entry->preempt_count		= trace_ctx & 0xff;
+	entry->migrate_disable		= (trace_ctx >> 8) & 0xff;
+	entry->preempt_lazy_count	= (trace_ctx >> 16) & 0xff;
+	entry->pid			= current->pid;
+	entry->type			= type;
+	entry->flags			= trace_ctx >> 24;
+}
+
+unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status);
+
+enum trace_flag_type {
+	TRACE_FLAG_IRQS_OFF		= 0x01,
+	TRACE_FLAG_IRQS_NOSUPPORT	= 0x02,
+	TRACE_FLAG_NEED_RESCHED		= 0x04,
+	TRACE_FLAG_HARDIRQ		= 0x08,
+	TRACE_FLAG_SOFTIRQ		= 0x10,
+	TRACE_FLAG_PREEMPT_RESCHED	= 0x20,
+	TRACE_FLAG_NMI			= 0x40,
+	TRACE_FLAG_NEED_RESCHED_LAZY	= 0x80,
+};
+
+#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
+static inline unsigned int tracing_gen_ctx_flags(unsigned long irqflags)
+{
+	unsigned int irq_status = irqs_disabled_flags(irqflags) ?
+		TRACE_FLAG_IRQS_OFF : 0;
+	return tracing_gen_ctx_irq_test(irq_status);
+}
+static inline unsigned int tracing_gen_ctx(void)
+{
+	unsigned long irqflags;
+
+	local_save_flags(irqflags);
+	return tracing_gen_ctx_flags(irqflags);
+}
+#else
+
+static inline unsigned int tracing_gen_ctx_flags(unsigned long irqflags)
+{
+	return tracing_gen_ctx_irq_test(TRACE_FLAG_IRQS_NOSUPPORT);
+}
+static inline unsigned int tracing_gen_ctx(void)
+{
+	return tracing_gen_ctx_irq_test(TRACE_FLAG_IRQS_NOSUPPORT);
+}
+#endif
+
+static inline unsigned int tracing_gen_ctx_dec(void)
+{
+	unsigned int trace_ctx;
+
+	trace_ctx = tracing_gen_ctx();
+	/*
+	 * Subtract one from the preeption counter if preemption is enabled,
+	 * see trace_event_buffer_reserve()for details.
+	 */
+	if (IS_ENABLED(CONFIG_PREEMPTION))
+		trace_ctx--;
+	return trace_ctx;
+}
+
 struct trace_event_file;
 
 struct ring_buffer_event *
 trace_event_buffer_lock_reserve(struct trace_buffer **current_buffer,
 				struct trace_event_file *trace_file,
 				int type, unsigned long len,
-				unsigned long flags, int pc);
+				unsigned int trace_ctx);
 
 #define TRACE_RECORD_CMDLINE	BIT(0)
 #define TRACE_RECORD_TGID	BIT(1)
@ include/linux/trace_events.h:298 @ struct trace_event_buffer {
 	struct ring_buffer_event	*event;
 	struct trace_event_file		*trace_file;
 	void				*entry;
-	unsigned long			flags;
-	int				pc;
+	unsigned int			trace_ctx;
 	struct pt_regs			*regs;
 };
 
@ include/linux/u64_stats_sync.h:69 @
 #include <linux/seqlock.h>
 
 struct u64_stats_sync {
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+#if BITS_PER_LONG==32 && (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT))
 	seqcount_t	seq;
 #endif
 };
@ include/linux/u64_stats_sync.h:118 @ static inline void u64_stats_inc(u64_stats_t *p)
 }
 #endif
 
-#if BITS_PER_LONG == 32 && defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT))
 #define u64_stats_init(syncp)	seqcount_init(&(syncp)->seq)
 #else
 static inline void u64_stats_init(struct u64_stats_sync *syncp)
@ include/linux/u64_stats_sync.h:128 @ static inline void u64_stats_init(struct u64_stats_sync *syncp)
 
 static inline void u64_stats_update_begin(struct u64_stats_sync *syncp)
 {
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT))
+	if (IS_ENABLED(CONFIG_PREEMPT_RT))
+		preempt_disable();
 	write_seqcount_begin(&syncp->seq);
 #endif
 }
 
 static inline void u64_stats_update_end(struct u64_stats_sync *syncp)
 {
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT))
 	write_seqcount_end(&syncp->seq);
+	if (IS_ENABLED(CONFIG_PREEMPT_RT))
+		preempt_enable();
 #endif
 }
 
@ include/linux/u64_stats_sync.h:149 @ u64_stats_update_begin_irqsave(struct u64_stats_sync *syncp)
 {
 	unsigned long flags = 0;
 
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
-	local_irq_save(flags);
+#if BITS_PER_LONG == 32 && (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT))
+	if (IS_ENABLED(CONFIG_PREEMPT_RT))
+		preempt_disable();
+	else
+		local_irq_save(flags);
 	write_seqcount_begin(&syncp->seq);
 #endif
 	return flags;
@ include/linux/u64_stats_sync.h:163 @ static inline void
 u64_stats_update_end_irqrestore(struct u64_stats_sync *syncp,
 				unsigned long flags)
 {
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT))
 	write_seqcount_end(&syncp->seq);
-	local_irq_restore(flags);
+	if (IS_ENABLED(CONFIG_PREEMPT_RT))
+		preempt_enable();
+	else
+		local_irq_restore(flags);
 #endif
 }
 
 static inline unsigned int __u64_stats_fetch_begin(const struct u64_stats_sync *syncp)
 {
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT))
 	return read_seqcount_begin(&syncp->seq);
 #else
 	return 0;
@ include/linux/u64_stats_sync.h:183 @ static inline unsigned int __u64_stats_fetch_begin(const struct u64_stats_sync *
 
 static inline unsigned int u64_stats_fetch_begin(const struct u64_stats_sync *syncp)
 {
-#if BITS_PER_LONG==32 && !defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && (!defined(CONFIG_SMP) && !defined(CONFIG_PREEMPT_RT))
 	preempt_disable();
 #endif
 	return __u64_stats_fetch_begin(syncp);
@ include/linux/u64_stats_sync.h:192 @ static inline unsigned int u64_stats_fetch_begin(const struct u64_stats_sync *sy
 static inline bool __u64_stats_fetch_retry(const struct u64_stats_sync *syncp,
 					 unsigned int start)
 {
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT))
 	return read_seqcount_retry(&syncp->seq, start);
 #else
 	return false;
@ include/linux/u64_stats_sync.h:202 @ static inline bool __u64_stats_fetch_retry(const struct u64_stats_sync *syncp,
 static inline bool u64_stats_fetch_retry(const struct u64_stats_sync *syncp,
 					 unsigned int start)
 {
-#if BITS_PER_LONG==32 && !defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && (!defined(CONFIG_SMP) && !defined(CONFIG_PREEMPT_RT))
 	preempt_enable();
 #endif
 	return __u64_stats_fetch_retry(syncp, start);
@ include/linux/u64_stats_sync.h:216 @ static inline bool u64_stats_fetch_retry(const struct u64_stats_sync *syncp,
  */
 static inline unsigned int u64_stats_fetch_begin_irq(const struct u64_stats_sync *syncp)
 {
-#if BITS_PER_LONG==32 && !defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && defined(CONFIG_PREEMPT_RT)
+	preempt_disable();
+#elif BITS_PER_LONG == 32 && !defined(CONFIG_SMP)
 	local_irq_disable();
 #endif
 	return __u64_stats_fetch_begin(syncp);
@ include/linux/u64_stats_sync.h:227 @ static inline unsigned int u64_stats_fetch_begin_irq(const struct u64_stats_sync
 static inline bool u64_stats_fetch_retry_irq(const struct u64_stats_sync *syncp,
 					     unsigned int start)
 {
-#if BITS_PER_LONG==32 && !defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && defined(CONFIG_PREEMPT_RT)
+	preempt_enable();
+#elif BITS_PER_LONG == 32 && !defined(CONFIG_SMP)
 	local_irq_enable();
 #endif
 	return __u64_stats_fetch_retry(syncp, start);
@ include/linux/vmstat.h:66 @ DECLARE_PER_CPU(struct vm_event_state, vm_event_states);
  */
 static inline void __count_vm_event(enum vm_event_item item)
 {
+	preempt_disable_rt();
 	raw_cpu_inc(vm_event_states.event[item]);
+	preempt_enable_rt();
 }
 
 static inline void count_vm_event(enum vm_event_item item)
@ include/linux/vmstat.h:78 @ static inline void count_vm_event(enum vm_event_item item)
 
 static inline void __count_vm_events(enum vm_event_item item, long delta)
 {
+	preempt_disable_rt();
 	raw_cpu_add(vm_event_states.event[item], delta);
+	preempt_enable_rt();
 }
 
 static inline void count_vm_events(enum vm_event_item item, long delta)
@ include/linux/vtime.h:86 @ static inline void vtime_init_idle(struct task_struct *tsk, int cpu) { }
 #endif
 
 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
-extern void vtime_account_irq_enter(struct task_struct *tsk);
-static inline void vtime_account_irq_exit(struct task_struct *tsk)
-{
-	/* On hard|softirq exit we always account to hard|softirq cputime */
-	vtime_account_kernel(tsk);
-}
+extern void vtime_account_irq(struct task_struct *tsk, unsigned int offset);
+extern void vtime_account_softirq(struct task_struct *tsk);
+extern void vtime_account_hardirq(struct task_struct *tsk);
 extern void vtime_flush(struct task_struct *tsk);
 #else /* !CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */
-static inline void vtime_account_irq_enter(struct task_struct *tsk) { }
-static inline void vtime_account_irq_exit(struct task_struct *tsk) { }
+static inline void vtime_account_irq(struct task_struct *tsk, unsigned int offset) { }
+static inline void vtime_account_softirq(struct task_struct *tsk) { }
+static inline void vtime_account_hardirq(struct task_struct *tsk) { }
 static inline void vtime_flush(struct task_struct *tsk) { }
 #endif
 
 
 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
-extern void irqtime_account_irq(struct task_struct *tsk);
+extern void irqtime_account_irq(struct task_struct *tsk, unsigned int offset);
 #else
-static inline void irqtime_account_irq(struct task_struct *tsk) { }
+static inline void irqtime_account_irq(struct task_struct *tsk, unsigned int offset) { }
 #endif
 
-static inline void account_irq_enter_time(struct task_struct *tsk)
+static inline void account_softirq_enter(struct task_struct *tsk)
+{
+	vtime_account_irq(tsk, SOFTIRQ_OFFSET);
+	irqtime_account_irq(tsk, SOFTIRQ_OFFSET);
+}
+
+static inline void account_softirq_exit(struct task_struct *tsk)
+{
+	vtime_account_softirq(tsk);
+	irqtime_account_irq(tsk, 0);
+}
+
+static inline void account_hardirq_enter(struct task_struct *tsk)
 {
-	vtime_account_irq_enter(tsk);
-	irqtime_account_irq(tsk);
+	vtime_account_irq(tsk, HARDIRQ_OFFSET);
+	irqtime_account_irq(tsk, HARDIRQ_OFFSET);
 }
 
-static inline void account_irq_exit_time(struct task_struct *tsk)
+static inline void account_hardirq_exit(struct task_struct *tsk)
 {
-	vtime_account_irq_exit(tsk);
-	irqtime_account_irq(tsk);
+	vtime_account_hardirq(tsk);
+	irqtime_account_irq(tsk, 0);
 }
 
 #endif /* _LINUX_KERNEL_VTIME_H */
@ include/linux/wait.h:13 @
 
 #include <asm/current.h>
 #include <uapi/linux/wait.h>
+#include <linux/atomic.h>
 
 typedef struct wait_queue_entry wait_queue_entry_t;
 
@ include/linux/ww_mutex.h:31 @ struct ww_class {
 	unsigned int is_wait_die;
 };
 
+struct ww_mutex {
+	struct mutex base;
+	struct ww_acquire_ctx *ctx;
+#ifdef CONFIG_DEBUG_MUTEXES
+	struct ww_class *ww_class;
+#endif
+};
+
 struct ww_acquire_ctx {
 	struct task_struct *task;
 	unsigned long stamp;
@ include/net/gen_stats.h:9 @
 #include <linux/socket.h>
 #include <linux/rtnetlink.h>
 #include <linux/pkt_sched.h>
+#include <net/net_seq_lock.h>
 
 /* Note: this used to be in include/uapi/linux/gen_stats.h */
 struct gnet_stats_basic_packed {
@ include/net/gen_stats.h:46 @ int gnet_stats_start_copy_compat(struct sk_buff *skb, int type,
 				 spinlock_t *lock, struct gnet_dump *d,
 				 int padattr);
 
-int gnet_stats_copy_basic(const seqcount_t *running,
+int gnet_stats_copy_basic(net_seqlock_t *running,
 			  struct gnet_dump *d,
 			  struct gnet_stats_basic_cpu __percpu *cpu,
 			  struct gnet_stats_basic_packed *b);
-void __gnet_stats_copy_basic(const seqcount_t *running,
+void __gnet_stats_copy_basic(net_seqlock_t *running,
 			     struct gnet_stats_basic_packed *bstats,
 			     struct gnet_stats_basic_cpu __percpu *cpu,
 			     struct gnet_stats_basic_packed *b);
-int gnet_stats_copy_basic_hw(const seqcount_t *running,
+int gnet_stats_copy_basic_hw(net_seqlock_t *running,
 			     struct gnet_dump *d,
 			     struct gnet_stats_basic_cpu __percpu *cpu,
 			     struct gnet_stats_basic_packed *b);
@ include/net/gen_stats.h:74 @ int gen_new_estimator(struct gnet_stats_basic_packed *bstats,
 		      struct gnet_stats_basic_cpu __percpu *cpu_bstats,
 		      struct net_rate_estimator __rcu **rate_est,
 		      spinlock_t *lock,
-		      seqcount_t *running, struct nlattr *opt);
+		      net_seqlock_t *running, struct nlattr *opt);
 void gen_kill_estimator(struct net_rate_estimator __rcu **ptr);
 int gen_replace_estimator(struct gnet_stats_basic_packed *bstats,
 			  struct gnet_stats_basic_cpu __percpu *cpu_bstats,
 			  struct net_rate_estimator __rcu **ptr,
 			  spinlock_t *lock,
-			  seqcount_t *running, struct nlattr *opt);
+			  net_seqlock_t *running, struct nlattr *opt);
 bool gen_estimator_active(struct net_rate_estimator __rcu **ptr);
 bool gen_estimator_read(struct net_rate_estimator __rcu **ptr,
 			struct gnet_stats_rate_est64 *sample);
@ include/net/net_seq_lock.h:4 @
+#ifndef __NET_NET_SEQ_LOCK_H__
+#define __NET_NET_SEQ_LOCK_H__
+
+#ifdef CONFIG_PREEMPT_RT
+# define net_seqlock_t			seqlock_t
+# define net_seq_begin(__r)		read_seqbegin(__r)
+# define net_seq_retry(__r, __s)	read_seqretry(__r, __s)
+
+#else
+# define net_seqlock_t			seqcount_t
+# define net_seq_begin(__r)		read_seqcount_begin(__r)
+# define net_seq_retry(__r, __s)	read_seqcount_retry(__r, __s)
+#endif
+
+#endif
@ include/net/netns/xfrm.h:76 @ struct netns_xfrm {
 	struct dst_ops		xfrm6_dst_ops;
 #endif
 	spinlock_t		xfrm_state_lock;
-	seqcount_t		xfrm_state_hash_generation;
+	seqcount_spinlock_t	xfrm_state_hash_generation;
 	seqcount_spinlock_t	xfrm_policy_hash_generation;
 
 	spinlock_t xfrm_policy_lock;
@ include/net/sch_generic.h:13 @
 #include <linux/percpu.h>
 #include <linux/dynamic_queue_limits.h>
 #include <linux/list.h>
+#include <net/net_seq_lock.h>
 #include <linux/refcount.h>
 #include <linux/workqueue.h>
 #include <linux/mutex.h>
@ include/net/sch_generic.h:105 @ struct Qdisc {
 	struct sk_buff_head	gso_skb ____cacheline_aligned_in_smp;
 	struct qdisc_skb_head	q;
 	struct gnet_stats_basic_packed bstats;
-	seqcount_t		running;
+	net_seqlock_t		running;
 	struct gnet_stats_queue	qstats;
 	unsigned long		state;
 	struct Qdisc            *next_sched;
@ include/net/sch_generic.h:146 @ static inline bool qdisc_is_running(struct Qdisc *qdisc)
 {
 	if (qdisc->flags & TCQ_F_NOLOCK)
 		return spin_is_locked(&qdisc->seqlock);
+#ifdef CONFIG_PREEMPT_RT
+	return spin_is_locked(&qdisc->running.lock) ? true : false;
+#else
 	return (raw_read_seqcount(&qdisc->running) & 1) ? true : false;
+#endif
 }
 
 static inline bool qdisc_is_percpu_stats(const struct Qdisc *q)
@ include/net/sch_generic.h:211 @ static inline bool qdisc_run_begin(struct Qdisc *qdisc)
 	} else if (qdisc_is_running(qdisc)) {
 		return false;
 	}
+#ifdef CONFIG_PREEMPT_RT
+	if (spin_trylock(&qdisc->running.lock)) {
+		seqcount_t *s = &qdisc->running.seqcount.seqcount;
+		/*
+		 * Variant of write_seqcount_t_begin() telling lockdep that a
+		 * trylock was attempted.
+		 */
+		raw_write_seqcount_t_begin(s);
+		seqcount_acquire(&s->dep_map, 0, 1, _RET_IP_);
+		return true;
+	}
+	return false;
+#else
 	/* Variant of write_seqcount_begin() telling lockdep a trylock
 	 * was attempted.
 	 */
 	raw_write_seqcount_begin(&qdisc->running);
 	seqcount_acquire(&qdisc->running.dep_map, 0, 1, _RET_IP_);
 	return true;
+#endif
 }
 
 static inline void qdisc_run_end(struct Qdisc *qdisc)
 {
+#ifdef CONFIG_PREEMPT_RT
+	write_sequnlock(&qdisc->running);
+#else
 	write_seqcount_end(&qdisc->running);
+#endif
 	if (qdisc->flags & TCQ_F_NOLOCK) {
 		spin_unlock(&qdisc->seqlock);
 
@ include/net/sch_generic.h:623 @ static inline spinlock_t *qdisc_root_sleeping_lock(const struct Qdisc *qdisc)
 	return qdisc_lock(root);
 }
 
-static inline seqcount_t *qdisc_root_sleeping_running(const struct Qdisc *qdisc)
+static inline net_seqlock_t *qdisc_root_sleeping_running(const struct Qdisc *qdisc)
 {
 	struct Qdisc *root = qdisc_root_sleeping(qdisc);
 
@ include/trace/events/sched.h:653 @ DECLARE_TRACE(sched_update_nr_running_tp,
 	TP_PROTO(struct rq *rq, int change),
 	TP_ARGS(rq, change));
 
+DECLARE_TRACE(sched_migrate_disable_tp,
+	      TP_PROTO(struct task_struct *p),
+	      TP_ARGS(p));
+
+DECLARE_TRACE(sched_migrate_enable_tp,
+	      TP_PROTO(struct task_struct *p),
+	      TP_ARGS(p));
+
+DECLARE_TRACE(sched_migrate_pull_tp,
+	      TP_PROTO(struct task_struct *p),
+	      TP_ARGS(p));
+
 #endif /* _TRACE_SCHED_H */
 
 /* This part must be outside protection */
@ init/Kconfig:864 @ config NUMA_BALANCING
 	bool "Memory placement aware NUMA scheduler"
 	depends on ARCH_SUPPORTS_NUMA_BALANCING
 	depends on !ARCH_WANT_NUMA_VARIABLE_LOCALITY
-	depends on SMP && NUMA && MIGRATION
+	depends on SMP && NUMA && MIGRATION && !PREEMPT_RT
 	help
 	  This option adds support for automatic NUMA aware memory/task placement.
 	  The mechanism is quite primitive and is based on migrating memory when
@ init/Kconfig:971 @ config CFS_BANDWIDTH
 config RT_GROUP_SCHED
 	bool "Group scheduling for SCHED_RR/FIFO"
 	depends on CGROUP_SCHED
+	depends on !PREEMPT_RT
 	default n
 	help
 	  This feature lets you explicitly allocate real CPU bandwidth
@ init/Kconfig:1909 @ choice
 
 config SLAB
 	bool "SLAB"
+	depends on !PREEMPT_RT
 	select HAVE_HARDENED_USERCOPY_ALLOCATOR
 	help
 	  The regular slab allocator that is established and known to work
@ init/Kconfig:1930 @ config SLUB
 config SLOB
 	depends on EXPERT
 	bool "SLOB (Simple Allocator)"
+	depends on !PREEMPT_RT
 	help
 	   SLOB replaces the stock allocator with a drastically simpler
 	   allocator. SLOB is generally more space efficient but
@ init/Kconfig:1997 @ config SHUFFLE_PAGE_ALLOCATOR
 
 config SLUB_CPU_PARTIAL
 	default y
-	depends on SLUB && SMP
+	depends on SLUB && SMP && !PREEMPT_RT
 	bool "SLUB per cpu partial cache"
 	help
 	  Per cpu partial caches accelerate objects allocation and freeing
@ kernel/Kconfig.locks:254 @ config ARCH_USE_QUEUED_RWLOCKS
 
 config QUEUED_RWLOCKS
 	def_bool y if ARCH_USE_QUEUED_RWLOCKS
-	depends on SMP
+	depends on SMP && !PREEMPT_RT
 
 config ARCH_HAS_MMIOWB
 	bool
@ kernel/Kconfig.preempt:4 @
 # SPDX-License-Identifier: GPL-2.0-only
 
+config HAVE_PREEMPT_LAZY
+	bool
+
+config PREEMPT_LAZY
+	def_bool y if HAVE_PREEMPT_LAZY && PREEMPT_RT
+
 choice
 	prompt "Preemption Model"
 	default PREEMPT_NONE
@ kernel/Kconfig.preempt:68 @ config PREEMPT_RT
 	bool "Fully Preemptible Kernel (Real-Time)"
 	depends on EXPERT && ARCH_SUPPORTS_RT
 	select PREEMPTION
+	select RT_MUTEXES
 	help
 	  This option turns the kernel into a real-time kernel by replacing
 	  various locking primitives (spinlocks, rwlocks, etc.) with
@ kernel/cgroup/cpuset.c:348 @ void cpuset_read_unlock(void)
 	percpu_up_read(&cpuset_rwsem);
 }
 
-static DEFINE_SPINLOCK(callback_lock);
+static DEFINE_RAW_SPINLOCK(callback_lock);
 
 static struct workqueue_struct *cpuset_migrate_mm_wq;
 
@ kernel/cgroup/cpuset.c:1285 @ static int update_parent_subparts_cpumask(struct cpuset *cpuset, int cmd,
 	 * Newly added CPUs will be removed from effective_cpus and
 	 * newly deleted ones will be added back to effective_cpus.
 	 */
-	spin_lock_irq(&callback_lock);
+	raw_spin_lock_irq(&callback_lock);
 	if (adding) {
 		cpumask_or(parent->subparts_cpus,
 			   parent->subparts_cpus, tmp->addmask);
@ kernel/cgroup/cpuset.c:1307 @ static int update_parent_subparts_cpumask(struct cpuset *cpuset, int cmd,
 
 	if (cpuset->partition_root_state != new_prs)
 		cpuset->partition_root_state = new_prs;
-	spin_unlock_irq(&callback_lock);
+	raw_spin_unlock_irq(&callback_lock);
 
 	return cmd == partcmd_update;
 }
@ kernel/cgroup/cpuset.c:1410 @ static void update_cpumasks_hier(struct cpuset *cs, struct tmpmasks *tmp)
 			continue;
 		rcu_read_unlock();
 
-		spin_lock_irq(&callback_lock);
+		raw_spin_lock_irq(&callback_lock);
 
 		cpumask_copy(cp->effective_cpus, tmp->new_cpus);
 		if (cp->nr_subparts_cpus && (new_prs != PRS_ENABLED)) {
@ kernel/cgroup/cpuset.c:1444 @ static void update_cpumasks_hier(struct cpuset *cs, struct tmpmasks *tmp)
 		if (new_prs != cp->partition_root_state)
 			cp->partition_root_state = new_prs;
 
-		spin_unlock_irq(&callback_lock);
+		raw_spin_unlock_irq(&callback_lock);
 
 		WARN_ON(!is_in_v2_mode() &&
 			!cpumask_equal(cp->cpus_allowed, cp->effective_cpus));
@ kernel/cgroup/cpuset.c:1562 @ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs,
 			return -EINVAL;
 	}
 
-	spin_lock_irq(&callback_lock);
+	raw_spin_lock_irq(&callback_lock);
 	cpumask_copy(cs->cpus_allowed, trialcs->cpus_allowed);
 
 	/*
@ kernel/cgroup/cpuset.c:1573 @ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs,
 			       cs->cpus_allowed);
 		cs->nr_subparts_cpus = cpumask_weight(cs->subparts_cpus);
 	}
-	spin_unlock_irq(&callback_lock);
+	raw_spin_unlock_irq(&callback_lock);
 
 	update_cpumasks_hier(cs, &tmp);
 
@ kernel/cgroup/cpuset.c:1767 @ static void update_nodemasks_hier(struct cpuset *cs, nodemask_t *new_mems)
 			continue;
 		rcu_read_unlock();
 
-		spin_lock_irq(&callback_lock);
+		raw_spin_lock_irq(&callback_lock);
 		cp->effective_mems = *new_mems;
-		spin_unlock_irq(&callback_lock);
+		raw_spin_unlock_irq(&callback_lock);
 
 		WARN_ON(!is_in_v2_mode() &&
 			!nodes_equal(cp->mems_allowed, cp->effective_mems));
@ kernel/cgroup/cpuset.c:1837 @ static int update_nodemask(struct cpuset *cs, struct cpuset *trialcs,
 	if (retval < 0)
 		goto done;
 
-	spin_lock_irq(&callback_lock);
+	raw_spin_lock_irq(&callback_lock);
 	cs->mems_allowed = trialcs->mems_allowed;
-	spin_unlock_irq(&callback_lock);
+	raw_spin_unlock_irq(&callback_lock);
 
 	/* use trialcs->mems_allowed as a temp variable */
 	update_nodemasks_hier(cs, &trialcs->mems_allowed);
@ kernel/cgroup/cpuset.c:1930 @ static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs,
 	spread_flag_changed = ((is_spread_slab(cs) != is_spread_slab(trialcs))
 			|| (is_spread_page(cs) != is_spread_page(trialcs)));
 
-	spin_lock_irq(&callback_lock);
+	raw_spin_lock_irq(&callback_lock);
 	cs->flags = trialcs->flags;
-	spin_unlock_irq(&callback_lock);
+	raw_spin_unlock_irq(&callback_lock);
 
 	if (!cpumask_empty(trialcs->cpus_allowed) && balance_flag_changed)
 		rebuild_sched_domains_locked();
@ kernel/cgroup/cpuset.c:2023 @ static int update_prstate(struct cpuset *cs, int new_prs)
 	rebuild_sched_domains_locked();
 out:
 	if (!err) {
-		spin_lock_irq(&callback_lock);
+		raw_spin_lock_irq(&callback_lock);
 		cs->partition_root_state = new_prs;
-		spin_unlock_irq(&callback_lock);
+		raw_spin_unlock_irq(&callback_lock);
 	}
 
 	free_cpumasks(NULL, &tmpmask);
@ kernel/cgroup/cpuset.c:2441 @ static int cpuset_common_seq_show(struct seq_file *sf, void *v)
 	cpuset_filetype_t type = seq_cft(sf)->private;
 	int ret = 0;
 
-	spin_lock_irq(&callback_lock);
+	raw_spin_lock_irq(&callback_lock);
 
 	switch (type) {
 	case FILE_CPULIST:
@ kernel/cgroup/cpuset.c:2463 @ static int cpuset_common_seq_show(struct seq_file *sf, void *v)
 		ret = -EINVAL;
 	}
 
-	spin_unlock_irq(&callback_lock);
+	raw_spin_unlock_irq(&callback_lock);
 	return ret;
 }
 
@ kernel/cgroup/cpuset.c:2776 @ static int cpuset_css_online(struct cgroup_subsys_state *css)
 
 	cpuset_inc();
 
-	spin_lock_irq(&callback_lock);
+	raw_spin_lock_irq(&callback_lock);
 	if (is_in_v2_mode()) {
 		cpumask_copy(cs->effective_cpus, parent->effective_cpus);
 		cs->effective_mems = parent->effective_mems;
 		cs->use_parent_ecpus = true;
 		parent->child_ecpus_count++;
 	}
-	spin_unlock_irq(&callback_lock);
+	raw_spin_unlock_irq(&callback_lock);
 
 	if (!test_bit(CGRP_CPUSET_CLONE_CHILDREN, &css->cgroup->flags))
 		goto out_unlock;
@ kernel/cgroup/cpuset.c:2810 @ static int cpuset_css_online(struct cgroup_subsys_state *css)
 	}
 	rcu_read_unlock();
 
-	spin_lock_irq(&callback_lock);
+	raw_spin_lock_irq(&callback_lock);
 	cs->mems_allowed = parent->mems_allowed;
 	cs->effective_mems = parent->mems_allowed;
 	cpumask_copy(cs->cpus_allowed, parent->cpus_allowed);
 	cpumask_copy(cs->effective_cpus, parent->cpus_allowed);
-	spin_unlock_irq(&callback_lock);
+	raw_spin_unlock_irq(&callback_lock);
 out_unlock:
 	percpu_up_write(&cpuset_rwsem);
 	put_online_cpus();
@ kernel/cgroup/cpuset.c:2871 @ static void cpuset_css_free(struct cgroup_subsys_state *css)
 static void cpuset_bind(struct cgroup_subsys_state *root_css)
 {
 	percpu_down_write(&cpuset_rwsem);
-	spin_lock_irq(&callback_lock);
+	raw_spin_lock_irq(&callback_lock);
 
 	if (is_in_v2_mode()) {
 		cpumask_copy(top_cpuset.cpus_allowed, cpu_possible_mask);
@ kernel/cgroup/cpuset.c:2882 @ static void cpuset_bind(struct cgroup_subsys_state *root_css)
 		top_cpuset.mems_allowed = top_cpuset.effective_mems;
 	}
 
-	spin_unlock_irq(&callback_lock);
+	raw_spin_unlock_irq(&callback_lock);
 	percpu_up_write(&cpuset_rwsem);
 }
 
@ kernel/cgroup/cpuset.c:2979 @ hotplug_update_tasks_legacy(struct cpuset *cs,
 {
 	bool is_empty;
 
-	spin_lock_irq(&callback_lock);
+	raw_spin_lock_irq(&callback_lock);
 	cpumask_copy(cs->cpus_allowed, new_cpus);
 	cpumask_copy(cs->effective_cpus, new_cpus);
 	cs->mems_allowed = *new_mems;
 	cs->effective_mems = *new_mems;
-	spin_unlock_irq(&callback_lock);
+	raw_spin_unlock_irq(&callback_lock);
 
 	/*
 	 * Don't call update_tasks_cpumask() if the cpuset becomes empty,
@ kernel/cgroup/cpuset.c:3021 @ hotplug_update_tasks(struct cpuset *cs,
 	if (nodes_empty(*new_mems))
 		*new_mems = parent_cs(cs)->effective_mems;
 
-	spin_lock_irq(&callback_lock);
+	raw_spin_lock_irq(&callback_lock);
 	cpumask_copy(cs->effective_cpus, new_cpus);
 	cs->effective_mems = *new_mems;
-	spin_unlock_irq(&callback_lock);
+	raw_spin_unlock_irq(&callback_lock);
 
 	if (cpus_updated)
 		update_tasks_cpumask(cs);
@ kernel/cgroup/cpuset.c:3091 @ static void cpuset_hotplug_update_tasks(struct cpuset *cs, struct tmpmasks *tmp)
 	if (is_partition_root(cs) && (cpumask_empty(&new_cpus) ||
 	   (parent->partition_root_state == PRS_ERROR))) {
 		if (cs->nr_subparts_cpus) {
-			spin_lock_irq(&callback_lock);
+			raw_spin_lock_irq(&callback_lock);
 			cs->nr_subparts_cpus = 0;
 			cpumask_clear(cs->subparts_cpus);
-			spin_unlock_irq(&callback_lock);
+			raw_spin_unlock_irq(&callback_lock);
 			compute_effective_cpumask(&new_cpus, cs, parent);
 		}
 
@ kernel/cgroup/cpuset.c:3108 @ static void cpuset_hotplug_update_tasks(struct cpuset *cs, struct tmpmasks *tmp)
 		     cpumask_empty(&new_cpus)) {
 			update_parent_subparts_cpumask(cs, partcmd_disable,
 						       NULL, tmp);
-			spin_lock_irq(&callback_lock);
+			raw_spin_lock_irq(&callback_lock);
 			cs->partition_root_state = PRS_ERROR;
-			spin_unlock_irq(&callback_lock);
+			raw_spin_unlock_irq(&callback_lock);
 		}
 		cpuset_force_rebuild();
 	}
@ kernel/cgroup/cpuset.c:3190 @ static void cpuset_hotplug_workfn(struct work_struct *work)
 
 	/* synchronize cpus_allowed to cpu_active_mask */
 	if (cpus_updated) {
-		spin_lock_irq(&callback_lock);
+		raw_spin_lock_irq(&callback_lock);
 		if (!on_dfl)
 			cpumask_copy(top_cpuset.cpus_allowed, &new_cpus);
 		/*
@ kernel/cgroup/cpuset.c:3210 @ static void cpuset_hotplug_workfn(struct work_struct *work)
 			}
 		}
 		cpumask_copy(top_cpuset.effective_cpus, &new_cpus);
-		spin_unlock_irq(&callback_lock);
+		raw_spin_unlock_irq(&callback_lock);
 		/* we don't mess with cpumasks of tasks in top_cpuset */
 	}
 
 	/* synchronize mems_allowed to N_MEMORY */
 	if (mems_updated) {
-		spin_lock_irq(&callback_lock);
+		raw_spin_lock_irq(&callback_lock);
 		if (!on_dfl)
 			top_cpuset.mems_allowed = new_mems;
 		top_cpuset.effective_mems = new_mems;
-		spin_unlock_irq(&callback_lock);
+		raw_spin_unlock_irq(&callback_lock);
 		update_tasks_nodemask(&top_cpuset);
 	}
 
@ kernel/cgroup/cpuset.c:3321 @ void cpuset_cpus_allowed(struct task_struct *tsk, struct cpumask *pmask)
 {
 	unsigned long flags;
 
-	spin_lock_irqsave(&callback_lock, flags);
+	raw_spin_lock_irqsave(&callback_lock, flags);
 	rcu_read_lock();
 	guarantee_online_cpus(task_cs(tsk), pmask);
 	rcu_read_unlock();
-	spin_unlock_irqrestore(&callback_lock, flags);
+	raw_spin_unlock_irqrestore(&callback_lock, flags);
 }
 
 /**
@ kernel/cgroup/cpuset.c:3386 @ nodemask_t cpuset_mems_allowed(struct task_struct *tsk)
 	nodemask_t mask;
 	unsigned long flags;
 
-	spin_lock_irqsave(&callback_lock, flags);
+	raw_spin_lock_irqsave(&callback_lock, flags);
 	rcu_read_lock();
 	guarantee_online_mems(task_cs(tsk), &mask);
 	rcu_read_unlock();
-	spin_unlock_irqrestore(&callback_lock, flags);
+	raw_spin_unlock_irqrestore(&callback_lock, flags);
 
 	return mask;
 }
@ kernel/cgroup/cpuset.c:3482 @ bool __cpuset_node_allowed(int node, gfp_t gfp_mask)
 		return true;
 
 	/* Not hardwall and node outside mems_allowed: scan up cpusets */
-	spin_lock_irqsave(&callback_lock, flags);
+	raw_spin_lock_irqsave(&callback_lock, flags);
 
 	rcu_read_lock();
 	cs = nearest_hardwall_ancestor(task_cs(current));
 	allowed = node_isset(node, cs->mems_allowed);
 	rcu_read_unlock();
 
-	spin_unlock_irqrestore(&callback_lock, flags);
+	raw_spin_unlock_irqrestore(&callback_lock, flags);
 	return allowed;
 }
 
@ kernel/cgroup/rstat.c:152 @ static void cgroup_rstat_flush_locked(struct cgroup *cgrp, bool may_sleep)
 		raw_spinlock_t *cpu_lock = per_cpu_ptr(&cgroup_rstat_cpu_lock,
 						       cpu);
 		struct cgroup *pos = NULL;
+		unsigned long flags;
 
-		raw_spin_lock(cpu_lock);
+		raw_spin_lock_irqsave(cpu_lock, flags);
 		while ((pos = cgroup_rstat_cpu_pop_updated(pos, cgrp, cpu))) {
 			struct cgroup_subsys_state *css;
 
@ kernel/cgroup/rstat.c:166 @ static void cgroup_rstat_flush_locked(struct cgroup *cgrp, bool may_sleep)
 				css->ss->css_rstat_flush(css, cpu);
 			rcu_read_unlock();
 		}
-		raw_spin_unlock(cpu_lock);
+		raw_spin_unlock_irqrestore(cpu_lock, flags);
 
 		/* if @may_sleep, play nice and yield if necessary */
 		if (may_sleep && (need_resched() ||
@ kernel/cpu.c:1665 @ static struct cpuhp_step cpuhp_hp_states[] = {
 		.name			= "ap:online",
 	},
 	/*
-	 * Handled on controll processor until the plugged processor manages
+	 * Handled on control processor until the plugged processor manages
 	 * this itself.
 	 */
 	[CPUHP_TEARDOWN_CPU] = {
@ kernel/cpu.c:1674 @ static struct cpuhp_step cpuhp_hp_states[] = {
 		.teardown.single	= takedown_cpu,
 		.cant_stop		= true,
 	},
+
+	[CPUHP_AP_SCHED_WAIT_EMPTY] = {
+		.name			= "sched:waitempty",
+		.startup.single		= NULL,
+		.teardown.single	= sched_cpu_wait_empty,
+	},
+
 	/* Handle smpboot threads park/unpark */
 	[CPUHP_AP_SMPBOOT_THREADS] = {
 		.name			= "smpboot/threads:online",
@ kernel/debug/kdb/kdb_main.c:2104 @ static int kdb_dmesg(int argc, const char **argv)
 	int adjust = 0;
 	int n = 0;
 	int skip = 0;
-	struct kmsg_dumper dumper = { .active = 1 };
+	struct kmsg_dumper_iter iter = { .active = 1 };
 	size_t len;
 	char buf[201];
 
@ kernel/debug/kdb/kdb_main.c:2129 @ static int kdb_dmesg(int argc, const char **argv)
 		kdb_set(2, setargs);
 	}
 
-	kmsg_dump_rewind_nolock(&dumper);
-	while (kmsg_dump_get_line_nolock(&dumper, 1, NULL, 0, NULL))
+	kmsg_dump_rewind(&iter);
+	while (kmsg_dump_get_line(&iter, 1, NULL, 0, NULL))
 		n++;
 
 	if (lines < 0) {
@ kernel/debug/kdb/kdb_main.c:2162 @ static int kdb_dmesg(int argc, const char **argv)
 	if (skip >= n || skip < 0)
 		return 0;
 
-	kmsg_dump_rewind_nolock(&dumper);
-	while (kmsg_dump_get_line_nolock(&dumper, 1, buf, sizeof(buf), &len)) {
+	kmsg_dump_rewind(&iter);
+	while (kmsg_dump_get_line(&iter, 1, buf, sizeof(buf), &len)) {
 		if (skip) {
 			skip--;
 			continue;
@ kernel/entry/common.c:5 @
 
 #include <linux/context_tracking.h>
 #include <linux/entry-common.h>
+#include <linux/highmem.h>
 #include <linux/livepatch.h>
 #include <linux/audit.h>
 
@ kernel/entry/common.c:152 @ static unsigned long exit_to_user_mode_loop(struct pt_regs *regs,
 
 		local_irq_enable_exit_to_user(ti_work);
 
-		if (ti_work & _TIF_NEED_RESCHED)
+		if (ti_work & _TIF_NEED_RESCHED_MASK)
 			schedule();
 
+#ifdef ARCH_RT_DELAYS_SIGNAL_SEND
+		if (unlikely(current->forced_info.si_signo)) {
+			struct task_struct *t = current;
+			force_sig_info(&t->forced_info);
+			t->forced_info.si_signo = 0;
+		}
+#endif
+
 		if (ti_work & _TIF_UPROBE)
 			uprobe_notify_resume(regs);
 
@ kernel/entry/common.c:206 @ static void exit_to_user_mode_prepare(struct pt_regs *regs)
 
 	/* Ensure that the address limit is intact and no locks are held */
 	addr_limit_user_check();
+	kmap_assert_nomap();
 	lockdep_assert_irqs_disabled();
 	lockdep_sys_exit();
 }
@ kernel/entry/common.c:366 @ void irqentry_exit_cond_resched(void)
 		rcu_irq_exit_check_preempt();
 		if (IS_ENABLED(CONFIG_DEBUG_ENTRY))
 			WARN_ON_ONCE(!on_thread_stack());
-		if (need_resched())
+		if (should_resched(0))
 			preempt_schedule_irq();
 	}
 }
@ kernel/exit.c:155 @ static void __exit_signal(struct task_struct *tsk)
 	 * Do this under ->siglock, we can race with another thread
 	 * doing sigqueue_free() if we have SIGQUEUE_PREALLOC signals.
 	 */
-	flush_sigqueue(&tsk->pending);
+	flush_task_sigqueue(tsk);
 	tsk->sighand = NULL;
 	spin_unlock(&sighand->siglock);
 
@ kernel/fork.c:45 @
 #include <linux/mmu_notifier.h>
 #include <linux/fs.h>
 #include <linux/mm.h>
+#include <linux/kprobes.h>
 #include <linux/vmacache.h>
 #include <linux/nsproxy.h>
 #include <linux/capability.h>
@ kernel/fork.c:292 @ static inline void free_thread_stack(struct task_struct *tsk)
 			return;
 		}
 
-		vfree_atomic(tsk->stack);
+		vfree(tsk->stack);
 		return;
 	}
 #endif
@ kernel/fork.c:692 @ void __mmdrop(struct mm_struct *mm)
 }
 EXPORT_SYMBOL_GPL(__mmdrop);
 
+#ifdef CONFIG_PREEMPT_RT
+/*
+ * RCU callback for delayed mm drop. Not strictly rcu, but we don't
+ * want another facility to make this work.
+ */
+void __mmdrop_delayed(struct rcu_head *rhp)
+{
+	struct mm_struct *mm = container_of(rhp, struct mm_struct, delayed_drop);
+
+	__mmdrop(mm);
+}
+#endif
+
 static void mmdrop_async_fn(struct work_struct *work)
 {
 	struct mm_struct *mm;
@ kernel/fork.c:746 @ void __put_task_struct(struct task_struct *tsk)
 	WARN_ON(refcount_read(&tsk->usage));
 	WARN_ON(tsk == current);
 
+	/*
+	 * Remove function-return probe instances associated with this
+	 * task and put them back on the free list.
+	 */
+	kprobe_flush_task(tsk);
+
+	/* Task is done with its stack. */
+	put_task_stack(tsk);
+
 	io_uring_free(tsk);
 	cgroup_free(tsk);
 	task_numa_free(tsk, true);
@ kernel/fork.c:952 @ static struct task_struct *dup_task_struct(struct task_struct *orig, int node)
 	tsk->splice_pipe = NULL;
 	tsk->task_frag.page = NULL;
 	tsk->wake_q.next = NULL;
+	tsk->wake_q_sleeper.next = NULL;
 
 	account_kernel_stack(tsk, 1);
 
 	kcov_task_init(tsk);
+	kmap_local_fork(tsk);
 
 #ifdef CONFIG_FAULT_INJECTION
 	tsk->fail_nth = 0;
@ kernel/fork.c:2029 @ static __latent_entropy struct task_struct *copy_process(
 	spin_lock_init(&p->alloc_lock);
 
 	init_sigpending(&p->pending);
+	p->sigqueue_cache = NULL;
 
 	p->utime = p->stime = p->gtime = 0;
 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
@ kernel/futex.c:1501 @ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_pi_state *pi_
 	struct task_struct *new_owner;
 	bool postunlock = false;
 	DEFINE_WAKE_Q(wake_q);
+	DEFINE_WAKE_Q(wake_sleeper_q);
 	int ret = 0;
 
 	new_owner = rt_mutex_next_owner(&pi_state->pi_mutex);
@ kernel/futex.c:1551 @ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_pi_state *pi_
 		 * not fail.
 		 */
 		pi_state_update_owner(pi_state, new_owner);
-		postunlock = __rt_mutex_futex_unlock(&pi_state->pi_mutex, &wake_q);
+		postunlock = __rt_mutex_futex_unlock(&pi_state->pi_mutex, &wake_q,
+						     &wake_sleeper_q);
 	}
 
 out_unlock:
 	raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock);
 
 	if (postunlock)
-		rt_mutex_postunlock(&wake_q);
+		rt_mutex_postunlock(&wake_q, &wake_sleeper_q);
 
 	return ret;
 }
@ kernel/futex.c:2160 @ static int futex_requeue(u32 __user *uaddr1, unsigned int flags,
 				 */
 				requeue_pi_wake_futex(this, &key2, hb2);
 				continue;
+			} else if (ret == -EAGAIN) {
+				/*
+				 * Waiter was woken by timeout or
+				 * signal and has set pi_blocked_on to
+				 * PI_WAKEUP_INPROGRESS before we
+				 * tried to enqueue it on the rtmutex.
+				 */
+				this->pi_state = NULL;
+				put_pi_state(pi_state);
+				continue;
 			} else if (ret) {
 				/*
 				 * rt_mutex_start_proxy_lock() detected a
@ kernel/futex.c:2862 @ static int futex_lock_pi(u32 __user *uaddr, unsigned int flags,
 		goto no_block;
 	}
 
-	rt_mutex_init_waiter(&rt_waiter);
+	rt_mutex_init_waiter(&rt_waiter, false);
 
 	/*
 	 * On PREEMPT_RT_FULL, when hb->lock becomes an rt_mutex, we must not
@ kernel/futex.c:3187 @ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
 {
 	struct hrtimer_sleeper timeout, *to;
 	struct rt_mutex_waiter rt_waiter;
-	struct futex_hash_bucket *hb;
+	struct futex_hash_bucket *hb, *hb2;
 	union futex_key key2 = FUTEX_KEY_INIT;
 	struct futex_q q = futex_q_init;
 	int res, ret;
@ kernel/futex.c:3208 @ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
 	 * The waiter is allocated on our stack, manipulated by the requeue
 	 * code while we sleep on uaddr.
 	 */
-	rt_mutex_init_waiter(&rt_waiter);
+	rt_mutex_init_waiter(&rt_waiter, false);
 
 	ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2, FUTEX_WRITE);
 	if (unlikely(ret != 0))
@ kernel/futex.c:3239 @ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
 	/* Queue the futex_q, drop the hb lock, wait for wakeup. */
 	futex_wait_queue_me(hb, &q, to);
 
-	spin_lock(&hb->lock);
-	ret = handle_early_requeue_pi_wakeup(hb, &q, &key2, to);
-	spin_unlock(&hb->lock);
-	if (ret)
-		goto out;
+	/*
+	 * On RT we must avoid races with requeue and trying to block
+	 * on two mutexes (hb->lock and uaddr2's rtmutex) by
+	 * serializing access to pi_blocked_on with pi_lock.
+	 */
+	raw_spin_lock_irq(&current->pi_lock);
+	if (current->pi_blocked_on) {
+		/*
+		 * We have been requeued or are in the process of
+		 * being requeued.
+		 */
+		raw_spin_unlock_irq(&current->pi_lock);
+	} else {
+		/*
+		 * Setting pi_blocked_on to PI_WAKEUP_INPROGRESS
+		 * prevents a concurrent requeue from moving us to the
+		 * uaddr2 rtmutex. After that we can safely acquire
+		 * (and possibly block on) hb->lock.
+		 */
+		current->pi_blocked_on = PI_WAKEUP_INPROGRESS;
+		raw_spin_unlock_irq(&current->pi_lock);
+
+		spin_lock(&hb->lock);
+
+		/*
+		 * Clean up pi_blocked_on. We might leak it otherwise
+		 * when we succeeded with the hb->lock in the fast
+		 * path.
+		 */
+		raw_spin_lock_irq(&current->pi_lock);
+		current->pi_blocked_on = NULL;
+		raw_spin_unlock_irq(&current->pi_lock);
+
+		ret = handle_early_requeue_pi_wakeup(hb, &q, &key2, to);
+		spin_unlock(&hb->lock);
+		if (ret)
+			goto out;
+	}
 
 	/*
-	 * In order for us to be here, we know our q.key == key2, and since
-	 * we took the hb->lock above, we also know that futex_requeue() has
-	 * completed and we no longer have to concern ourselves with a wakeup
-	 * race with the atomic proxy lock acquisition by the requeue code. The
-	 * futex_requeue dropped our key1 reference and incremented our key2
-	 * reference count.
+	 * In order to be here, we have either been requeued, are in
+	 * the process of being requeued, or requeue successfully
+	 * acquired uaddr2 on our behalf.  If pi_blocked_on was
+	 * non-null above, we may be racing with a requeue.  Do not
+	 * rely on q->lock_ptr to be hb2->lock until after blocking on
+	 * hb->lock or hb2->lock. The futex_requeue dropped our key1
+	 * reference and incremented our key2 reference count.
 	 */
+	hb2 = hash_futex(&key2);
 
 	/* Check if the requeue code acquired the second futex for us. */
 	if (!q.rt_waiter) {
@ kernel/futex.c:3296 @ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
 		 * did a lock-steal - fix up the PI-state in that case.
 		 */
 		if (q.pi_state && (q.pi_state->owner != current)) {
-			spin_lock(q.lock_ptr);
+			spin_lock(&hb2->lock);
+			BUG_ON(&hb2->lock != q.lock_ptr);
 			ret = fixup_pi_state_owner(uaddr2, &q, current);
 			/*
 			 * Drop the reference to the pi state which
 			 * the requeue_pi() code acquired for us.
 			 */
 			put_pi_state(q.pi_state);
-			spin_unlock(q.lock_ptr);
+			spin_unlock(&hb2->lock);
 			/*
 			 * Adjust the return value. It's either -EFAULT or
 			 * success (1) but the caller expects 0 for success.
@ kernel/futex.c:3323 @ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
 		pi_mutex = &q.pi_state->pi_mutex;
 		ret = rt_mutex_wait_proxy_lock(pi_mutex, to, &rt_waiter);
 
-		spin_lock(q.lock_ptr);
+		spin_lock(&hb2->lock);
+		BUG_ON(&hb2->lock != q.lock_ptr);
 		if (ret && !rt_mutex_cleanup_proxy_lock(pi_mutex, &rt_waiter))
 			ret = 0;
 
@ kernel/irq/handle.c:195 @ irqreturn_t handle_irq_event_percpu(struct irq_desc *desc)
 {
 	irqreturn_t retval;
 	unsigned int flags = 0;
+	struct pt_regs *regs = get_irq_regs();
+	u64 ip = regs ? instruction_pointer(regs) : 0;
 
 	retval = __handle_irq_event_percpu(desc, &flags);
 
-	add_interrupt_randomness(desc->irq_data.irq, flags);
+#ifdef CONFIG_PREEMPT_RT
+	desc->random_ip = ip;
+#else
+	add_interrupt_randomness(desc->irq_data.irq, flags, ip);
+#endif
 
 	if (!noirqdebug)
 		note_interrupt(desc, retval);
@ kernel/irq/manage.c:1162 @ static int irq_thread(void *data)
 	irqreturn_t (*handler_fn)(struct irq_desc *desc,
 			struct irqaction *action);
 
+	sched_set_fifo(current);
+
 	if (force_irqthreads && test_bit(IRQTF_FORCED_THREAD,
 					&action->thread_flags))
 		handler_fn = irq_forced_thread_fn;
@ kernel/irq/manage.c:1184 @ static int irq_thread(void *data)
 		if (action_ret == IRQ_WAKE_THREAD)
 			irq_wake_secondary(desc, action);
 
+		if (IS_ENABLED(CONFIG_PREEMPT_RT)) {
+			migrate_disable();
+			add_interrupt_randomness(action->irq, 0,
+				 desc->random_ip ^ (unsigned long) action);
+			migrate_enable();
+		}
 		wake_threads_waitq(desc);
 	}
 
@ kernel/irq/manage.c:1335 @ setup_irq_thread(struct irqaction *new, unsigned int irq, bool secondary)
 	if (IS_ERR(t))
 		return PTR_ERR(t);
 
-	sched_set_fifo(t);
-
 	/*
 	 * We keep the reference to the task struct even if
 	 * the thread dies to avoid that the interrupt code
@ kernel/irq/manage.c:2724 @ EXPORT_SYMBOL_GPL(irq_get_irqchip_state);
  *	This call sets the internal irqchip state of an interrupt,
  *	depending on the value of @which.
  *
- *	This function should be called with preemption disabled if the
+ *	This function should be called with migration disabled if the
  *	interrupt controller has per-cpu registers.
  */
 int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
@ kernel/irq/spurious.c:446 @ MODULE_PARM_DESC(noirqdebug, "Disable irq lockup detection when true");
 
 static int __init irqfixup_setup(char *str)
 {
+#ifdef CONFIG_PREEMPT_RT
+	pr_warn("irqfixup boot option not supported w/ CONFIG_PREEMPT_RT\n");
+	return 1;
+#endif
 	irqfixup = 1;
 	printk(KERN_WARNING "Misrouted IRQ fixup support enabled.\n");
 	printk(KERN_WARNING "This may impact system performance.\n");
@ kernel/irq/spurious.c:462 @ module_param(irqfixup, int, 0644);
 
 static int __init irqpoll_setup(char *str)
 {
+#ifdef CONFIG_PREEMPT_RT
+	pr_warn("irqpoll boot option not supported w/ CONFIG_PREEMPT_RT\n");
+	return 1;
+#endif
 	irqfixup = 2;
 	printk(KERN_WARNING "Misrouted IRQ fixup and polling support "
 				"enabled\n");
@ kernel/irq_work.c:21 @
 #include <linux/cpu.h>
 #include <linux/notifier.h>
 #include <linux/smp.h>
+#include <linux/smpboot.h>
+#include <linux/interrupt.h>
 #include <asm/processor.h>
 
 
 static DEFINE_PER_CPU(struct llist_head, raised_list);
 static DEFINE_PER_CPU(struct llist_head, lazy_list);
+static DEFINE_PER_CPU(struct task_struct *, irq_workd);
+
+static void wake_irq_workd(void)
+{
+	struct task_struct *tsk = __this_cpu_read(irq_workd);
+
+	if (!llist_empty(this_cpu_ptr(&lazy_list)) && tsk)
+		wake_up_process(tsk);
+}
+
+#ifdef CONFIG_SMP
+static void irq_work_wake(struct irq_work *entry)
+{
+	wake_irq_workd();
+}
+
+static DEFINE_PER_CPU(struct irq_work, irq_work_wakeup) =
+	IRQ_WORK_INIT_HARD(irq_work_wake);
+#endif
+
+static int irq_workd_should_run(unsigned int cpu)
+{
+	return !llist_empty(this_cpu_ptr(&lazy_list));
+}
 
 /*
  * Claim the entry so that no one else will poke at it.
@ kernel/irq_work.c:81 @ void __weak arch_irq_work_raise(void)
 /* Enqueue on current CPU, work must already be claimed and preempt disabled */
 static void __irq_work_queue_local(struct irq_work *work)
 {
+	struct llist_head *list;
+	bool rt_lazy_work = false;
+	bool lazy_work = false;
+	int work_flags;
+
+	work_flags = atomic_read(&work->flags);
+	if (work_flags & IRQ_WORK_LAZY)
+		lazy_work = true;
+	else if (IS_ENABLED(CONFIG_PREEMPT_RT) &&
+		 !(work_flags & IRQ_WORK_HARD_IRQ))
+		rt_lazy_work = true;
+
+	if (lazy_work || rt_lazy_work)
+		list = this_cpu_ptr(&lazy_list);
+	else
+		list = this_cpu_ptr(&raised_list);
+
+	if (!llist_add(&work->llnode, list))
+		return;
+
 	/* If the work is "lazy", handle it from next tick if any */
-	if (atomic_read(&work->flags) & IRQ_WORK_LAZY) {
-		if (llist_add(&work->llnode, this_cpu_ptr(&lazy_list)) &&
-		    tick_nohz_tick_stopped())
-			arch_irq_work_raise();
-	} else {
-		if (llist_add(&work->llnode, this_cpu_ptr(&raised_list)))
-			arch_irq_work_raise();
-	}
+	if (!lazy_work || tick_nohz_tick_stopped())
+		arch_irq_work_raise();
 }
 
 /* Enqueue the irq work @work on the current CPU */
@ kernel/irq_work.c:145 @ bool irq_work_queue_on(struct irq_work *work, int cpu)
 	if (cpu != smp_processor_id()) {
 		/* Arch remote IPI send/receive backend aren't NMI safe */
 		WARN_ON_ONCE(in_nmi());
+
+		/*
+		 * On PREEMPT_RT the items which are not marked as
+		 * IRQ_WORK_HARD_IRQ are added to the lazy list and a HARD work
+		 * item is used on the remote CPU to wake the thread.
+		 */
+		if (IS_ENABLED(CONFIG_PREEMPT_RT) &&
+		    !(atomic_read(&work->flags) & IRQ_WORK_HARD_IRQ)) {
+
+			if (!llist_add(&work->llnode, &per_cpu(lazy_list, cpu)))
+				goto out;
+
+			work = &per_cpu(irq_work_wakeup, cpu);
+			if (!irq_work_claim(work))
+				goto out;
+		}
+
 		__smp_call_single_queue(cpu, &work->llnode);
 	} else {
 		__irq_work_queue_local(work);
 	}
+out:
 	preempt_enable();
 
 	return true;
@ kernel/irq_work.c:181 @ bool irq_work_needs_cpu(void)
 	raised = this_cpu_ptr(&raised_list);
 	lazy = this_cpu_ptr(&lazy_list);
 
-	if (llist_empty(raised) || arch_irq_work_has_interrupt())
-		if (llist_empty(lazy))
-			return false;
+	if (llist_empty(raised) && llist_empty(lazy))
+		return false;
 
 	/* All work should have been flushed before going offline */
 	WARN_ON_ONCE(cpu_is_offline(smp_processor_id()));
@ kernel/irq_work.c:213 @ void irq_work_single(void *arg)
 	 */
 	flags &= ~IRQ_WORK_PENDING;
 	(void)atomic_cmpxchg(&work->flags, flags, flags & ~IRQ_WORK_BUSY);
+
+	if ((IS_ENABLED(CONFIG_PREEMPT_RT) && !irq_work_is_hard(work)) ||
+	    !arch_irq_work_has_interrupt())
+		rcuwait_wake_up(&work->irqwait);
 }
 
 static void irq_work_run_list(struct llist_head *list)
@ kernel/irq_work.c:224 @ static void irq_work_run_list(struct llist_head *list)
 	struct irq_work *work, *tmp;
 	struct llist_node *llnode;
 
-	BUG_ON(!irqs_disabled());
+	/*
+	 * On PREEMPT_RT IRQ-work which is not marked as HARD will be processed
+	 * in a per-CPU thread in preemptible context. Only the items which are
+	 * marked as IRQ_WORK_HARD_IRQ will be processed in hardirq context.
+	 */
+	BUG_ON(!irqs_disabled() && !IS_ENABLED(CONFIG_PREEMPT_RT));
 
 	if (llist_empty(list))
 		return;
@ kernel/irq_work.c:246 @ static void irq_work_run_list(struct llist_head *list)
 void irq_work_run(void)
 {
 	irq_work_run_list(this_cpu_ptr(&raised_list));
-	irq_work_run_list(this_cpu_ptr(&lazy_list));
+	if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+		irq_work_run_list(this_cpu_ptr(&lazy_list));
+	else
+		wake_irq_workd();
 }
 EXPORT_SYMBOL_GPL(irq_work_run);
 
@ kernel/irq_work.c:259 @ void irq_work_tick(void)
 
 	if (!llist_empty(raised) && !arch_irq_work_has_interrupt())
 		irq_work_run_list(raised);
-	irq_work_run_list(this_cpu_ptr(&lazy_list));
+
+	if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+		irq_work_run_list(this_cpu_ptr(&lazy_list));
+	else
+		wake_irq_workd();
 }
 
 /*
@ kernel/irq_work.c:273 @ void irq_work_tick(void)
 void irq_work_sync(struct irq_work *work)
 {
 	lockdep_assert_irqs_enabled();
+	might_sleep();
+
+	if ((IS_ENABLED(CONFIG_PREEMPT_RT) && !irq_work_is_hard(work)) ||
+	    !arch_irq_work_has_interrupt()) {
+		rcuwait_wait_event(&work->irqwait, !irq_work_is_busy(work),
+				   TASK_UNINTERRUPTIBLE);
+		return;
+	}
 
 	while (atomic_read(&work->flags) & IRQ_WORK_BUSY)
 		cpu_relax();
 }
 EXPORT_SYMBOL_GPL(irq_work_sync);
+
+static void run_irq_workd(unsigned int cpu)
+{
+	irq_work_run_list(this_cpu_ptr(&lazy_list));
+}
+
+static void irq_workd_setup(unsigned int cpu)
+{
+	sched_set_fifo_low(current);
+}
+
+static struct smp_hotplug_thread irqwork_threads = {
+	.store                  = &irq_workd,
+	.setup			= irq_workd_setup,
+	.thread_should_run      = irq_workd_should_run,
+	.thread_fn              = run_irq_workd,
+	.thread_comm            = "irq_work/%u",
+};
+
+static __init int irq_work_init_threads(void)
+{
+	if (IS_ENABLED(CONFIG_PREEMPT_RT))
+		BUG_ON(smpboot_register_percpu_thread(&irqwork_threads));
+	return 0;
+}
+early_initcall(irq_work_init_threads);
@ kernel/kexec_core.c:981 @ void crash_kexec(struct pt_regs *regs)
 	old_cpu = atomic_cmpxchg(&panic_cpu, PANIC_CPU_INVALID, this_cpu);
 	if (old_cpu == PANIC_CPU_INVALID) {
 		/* This is the 1st CPU which comes here, so go ahead. */
-		printk_safe_flush_on_panic();
 		__crash_kexec(regs);
 
 		/*
@ kernel/ksysfs.c:141 @ KERNEL_ATTR_RO(vmcoreinfo);
 
 #endif /* CONFIG_CRASH_CORE */
 
+#if defined(CONFIG_PREEMPT_RT)
+static ssize_t realtime_show(struct kobject *kobj,
+			     struct kobj_attribute *attr, char *buf)
+{
+	return sprintf(buf, "%d\n", 1);
+}
+KERNEL_ATTR_RO(realtime);
+#endif
+
 /* whether file capabilities are enabled */
 static ssize_t fscaps_show(struct kobject *kobj,
 				  struct kobj_attribute *attr, char *buf)
@ kernel/ksysfs.c:240 @ static struct attribute * kernel_attrs[] = {
 #ifndef CONFIG_TINY_RCU
 	&rcu_expedited_attr.attr,
 	&rcu_normal_attr.attr,
+#endif
+#ifdef CONFIG_PREEMPT_RT
+	&realtime_attr.attr,
 #endif
 	NULL
 };
@ kernel/kthread.c:267 @ EXPORT_SYMBOL_GPL(kthread_parkme);
 
 static int kthread(void *_create)
 {
+	static const struct sched_param param = { .sched_priority = 0 };
 	/* Copy data: it's on kthread's stack */
 	struct kthread_create_info *create = _create;
 	int (*threadfn)(void *data) = create->threadfn;
@ kernel/kthread.c:298 @ static int kthread(void *_create)
 	init_completion(&self->parked);
 	current->vfork_done = &self->exited;
 
+	/*
+	 * The new thread inherited kthreadd's priority and CPU mask. Reset
+	 * back to default in case they have been changed.
+	 */
+	sched_setscheduler_nocheck(current, SCHED_NORMAL, &param);
+	set_cpus_allowed_ptr(current, housekeeping_cpumask(HK_FLAG_KTHREAD));
+
 	/* OK, tell user we're spawned, wait for stop or wakeup */
 	__set_current_state(TASK_UNINTERRUPTIBLE);
 	create->result = current;
@ kernel/kthread.c:402 @ struct task_struct *__kthread_create_on_node(int (*threadfn)(void *data),
 	}
 	task = create->result;
 	if (!IS_ERR(task)) {
-		static const struct sched_param param = { .sched_priority = 0 };
 		char name[TASK_COMM_LEN];
 
 		/*
@ kernel/kthread.c:410 @ struct task_struct *__kthread_create_on_node(int (*threadfn)(void *data),
 		 */
 		vsnprintf(name, sizeof(name), namefmt, args);
 		set_task_comm(task, name);
-		/*
-		 * root may have changed our (kthreadd's) priority or CPU mask.
-		 * The kernel thread should not inherit these properties.
-		 */
-		sched_setscheduler_nocheck(task, SCHED_NORMAL, &param);
-		set_cpus_allowed_ptr(task,
-				     housekeeping_cpumask(HK_FLAG_KTHREAD));
 	}
 	kfree(create);
 	return task;
@ kernel/locking/Makefile:6 @
 # and is generally not a function of system call inputs.
 KCOV_INSTRUMENT		:= n
 
-obj-y += mutex.o semaphore.o rwsem.o percpu-rwsem.o
+obj-y += semaphore.o rwsem.o percpu-rwsem.o
 
 # Avoid recursion lockdep -> KCSAN -> ... -> lockdep.
 KCSAN_SANITIZE_lockdep.o := n
@ kernel/locking/Makefile:18 @ CFLAGS_REMOVE_mutex-debug.o = $(CC_FLAGS_FTRACE)
 CFLAGS_REMOVE_rtmutex-debug.o = $(CC_FLAGS_FTRACE)
 endif
 
-obj-$(CONFIG_DEBUG_MUTEXES) += mutex-debug.o
 obj-$(CONFIG_LOCKDEP) += lockdep.o
 ifeq ($(CONFIG_PROC_FS),y)
 obj-$(CONFIG_LOCKDEP) += lockdep_proc.o
 endif
 obj-$(CONFIG_SMP) += spinlock.o
-obj-$(CONFIG_LOCK_SPIN_ON_OWNER) += osq_lock.o
 obj-$(CONFIG_PROVE_LOCKING) += spinlock.o
 obj-$(CONFIG_QUEUED_SPINLOCKS) += qspinlock.o
 obj-$(CONFIG_RT_MUTEXES) += rtmutex.o
 obj-$(CONFIG_DEBUG_RT_MUTEXES) += rtmutex-debug.o
 obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock.o
 obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock_debug.o
+ifneq ($(CONFIG_PREEMPT_RT),y)
+obj-y += mutex.o
+obj-$(CONFIG_LOCK_SPIN_ON_OWNER) += osq_lock.o
+obj-$(CONFIG_DEBUG_MUTEXES) += mutex-debug.o
+endif
+obj-$(CONFIG_PREEMPT_RT) += mutex-rt.o rwsem-rt.o rwlock-rt.o
 obj-$(CONFIG_QUEUED_RWLOCKS) += qrwlock.o
 obj-$(CONFIG_LOCK_TORTURE_TEST) += locktorture.o
 obj-$(CONFIG_WW_MUTEX_SELFTEST) += test-ww_mutex.o
@ kernel/locking/lockdep.c:5413 @ static noinstr void check_flags(unsigned long flags)
 		}
 	}
 
+#ifndef CONFIG_PREEMPT_RT
 	/*
 	 * We dont accurately track softirq state in e.g.
 	 * hardirq contexts (such as on 4KSTACKS), so only
@ kernel/locking/lockdep.c:5428 @ static noinstr void check_flags(unsigned long flags)
 			DEBUG_LOCKS_WARN_ON(!current->softirqs_enabled);
 		}
 	}
+#endif
 
 	if (!debug_locks)
 		print_irqtrace_events(current);
@ kernel/locking/mutex-rt.c:4 @
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Real-Time Preemption Support
+ *
+ * started by Ingo Molnar:
+ *
+ *  Copyright (C) 2004-2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
+ *  Copyright (C) 2006, Timesys Corp., Thomas Gleixner <tglx@timesys.com>
+ *
+ * historic credit for proving that Linux spinlocks can be implemented via
+ * RT-aware mutexes goes to many people: The Pmutex project (Dirk Grambow
+ * and others) who prototyped it on 2.4 and did lots of comparative
+ * research and analysis; TimeSys, for proving that you can implement a
+ * fully preemptible kernel via the use of IRQ threading and mutexes;
+ * Bill Huey for persuasively arguing on lkml that the mutex model is the
+ * right one; and to MontaVista, who ported pmutexes to 2.6.
+ *
+ * This code is a from-scratch implementation and is not based on pmutexes,
+ * but the idea of converting spinlocks to mutexes is used here too.
+ *
+ * lock debugging, locking tree, deadlock detection:
+ *
+ *  Copyright (C) 2004, LynuxWorks, Inc., Igor Manyilov, Bill Huey
+ *  Released under the General Public License (GPL).
+ *
+ * Includes portions of the generic R/W semaphore implementation from:
+ *
+ *  Copyright (c) 2001   David Howells (dhowells@redhat.com).
+ *  - Derived partially from idea by Andrea Arcangeli <andrea@suse.de>
+ *  - Derived also from comments by Linus
+ *
+ * Pending ownership of locks and ownership stealing:
+ *
+ *  Copyright (C) 2005, Kihon Technologies Inc., Steven Rostedt
+ *
+ *   (also by Steven Rostedt)
+ *    - Converted single pi_lock to individual task locks.
+ *
+ * By Esben Nielsen:
+ *    Doing priority inheritance with help of the scheduler.
+ *
+ *  Copyright (C) 2006, Timesys Corp., Thomas Gleixner <tglx@timesys.com>
+ *  - major rework based on Esben Nielsens initial patch
+ *  - replaced thread_info references by task_struct refs
+ *  - removed task->pending_owner dependency
+ *  - BKL drop/reacquire for semaphore style locks to avoid deadlocks
+ *    in the scheduler return path as discussed with Steven Rostedt
+ *
+ *  Copyright (C) 2006, Kihon Technologies Inc.
+ *    Steven Rostedt <rostedt@goodmis.org>
+ *  - debugged and patched Thomas Gleixner's rework.
+ *  - added back the cmpxchg to the rework.
+ *  - turned atomic require back on for SMP.
+ */
+
+#include <linux/spinlock.h>
+#include <linux/rtmutex.h>
+#include <linux/sched.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/kallsyms.h>
+#include <linux/syscalls.h>
+#include <linux/interrupt.h>
+#include <linux/plist.h>
+#include <linux/fs.h>
+#include <linux/futex.h>
+#include <linux/hrtimer.h>
+#include <linux/blkdev.h>
+
+#include "rtmutex_common.h"
+
+/*
+ * struct mutex functions
+ */
+void __mutex_do_init(struct mutex *mutex, const char *name,
+		     struct lock_class_key *key)
+{
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+	/*
+	 * Make sure we are not reinitializing a held lock:
+	 */
+	debug_check_no_locks_freed((void *)mutex, sizeof(*mutex));
+	lockdep_init_map(&mutex->dep_map, name, key, 0);
+#endif
+	mutex->lock.save_state = 0;
+}
+EXPORT_SYMBOL(__mutex_do_init);
+
+static int _mutex_lock_blk_flush(struct mutex *lock, int state)
+{
+	/*
+	 * Flush blk before ->pi_blocked_on is set. At schedule() time it is too
+	 * late if one of the callbacks needs to acquire a sleeping lock.
+	 */
+	if (blk_needs_flush_plug(current))
+		blk_schedule_flush_plug(current);
+	return __rt_mutex_lock_state(&lock->lock, state);
+}
+
+void __lockfunc _mutex_lock(struct mutex *lock)
+{
+	mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+	_mutex_lock_blk_flush(lock, TASK_UNINTERRUPTIBLE);
+}
+EXPORT_SYMBOL(_mutex_lock);
+
+void __lockfunc _mutex_lock_io_nested(struct mutex *lock, int subclass)
+{
+	int token;
+
+	token = io_schedule_prepare();
+
+	mutex_acquire_nest(&lock->dep_map, subclass, 0, NULL, _RET_IP_);
+	__rt_mutex_lock_state(&lock->lock, TASK_UNINTERRUPTIBLE);
+
+	io_schedule_finish(token);
+}
+EXPORT_SYMBOL_GPL(_mutex_lock_io_nested);
+
+int __lockfunc _mutex_lock_interruptible(struct mutex *lock)
+{
+	int ret;
+
+	mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+	ret = _mutex_lock_blk_flush(lock, TASK_INTERRUPTIBLE);
+	if (ret)
+		mutex_release(&lock->dep_map, _RET_IP_);
+	return ret;
+}
+EXPORT_SYMBOL(_mutex_lock_interruptible);
+
+int __lockfunc _mutex_lock_killable(struct mutex *lock)
+{
+	int ret;
+
+	mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+	ret = _mutex_lock_blk_flush(lock, TASK_KILLABLE);
+	if (ret)
+		mutex_release(&lock->dep_map, _RET_IP_);
+	return ret;
+}
+EXPORT_SYMBOL(_mutex_lock_killable);
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+void __lockfunc _mutex_lock_nested(struct mutex *lock, int subclass)
+{
+	mutex_acquire_nest(&lock->dep_map, subclass, 0, NULL, _RET_IP_);
+	_mutex_lock_blk_flush(lock, TASK_UNINTERRUPTIBLE);
+}
+EXPORT_SYMBOL(_mutex_lock_nested);
+
+void __lockfunc _mutex_lock_nest_lock(struct mutex *lock, struct lockdep_map *nest)
+{
+	mutex_acquire_nest(&lock->dep_map, 0, 0, nest, _RET_IP_);
+	_mutex_lock_blk_flush(lock, TASK_UNINTERRUPTIBLE);
+}
+EXPORT_SYMBOL(_mutex_lock_nest_lock);
+
+int __lockfunc _mutex_lock_interruptible_nested(struct mutex *lock, int subclass)
+{
+	int ret;
+
+	mutex_acquire_nest(&lock->dep_map, subclass, 0, NULL, _RET_IP_);
+	ret = _mutex_lock_blk_flush(lock, TASK_INTERRUPTIBLE);
+	if (ret)
+		mutex_release(&lock->dep_map, _RET_IP_);
+	return ret;
+}
+EXPORT_SYMBOL(_mutex_lock_interruptible_nested);
+
+int __lockfunc _mutex_lock_killable_nested(struct mutex *lock, int subclass)
+{
+	int ret;
+
+	mutex_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
+	ret = _mutex_lock_blk_flush(lock, TASK_KILLABLE);
+	if (ret)
+		mutex_release(&lock->dep_map, _RET_IP_);
+	return ret;
+}
+EXPORT_SYMBOL(_mutex_lock_killable_nested);
+#endif
+
+int __lockfunc _mutex_trylock(struct mutex *lock)
+{
+	int ret = __rt_mutex_trylock(&lock->lock);
+
+	if (ret)
+		mutex_acquire(&lock->dep_map, 0, 1, _RET_IP_);
+
+	return ret;
+}
+EXPORT_SYMBOL(_mutex_trylock);
+
+void __lockfunc _mutex_unlock(struct mutex *lock)
+{
+	mutex_release(&lock->dep_map, _RET_IP_);
+	__rt_mutex_unlock(&lock->lock);
+}
+EXPORT_SYMBOL(_mutex_unlock);
+
+/**
+ * atomic_dec_and_mutex_lock - return holding mutex if we dec to 0
+ * @cnt: the atomic which we are to dec
+ * @lock: the mutex to return holding if we dec to 0
+ *
+ * return true and hold lock if we dec to 0, return false otherwise
+ */
+int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock)
+{
+	/* dec if we can't possibly hit 0 */
+	if (atomic_add_unless(cnt, -1, 1))
+		return 0;
+	/* we might hit 0, so take the lock */
+	mutex_lock(lock);
+	if (!atomic_dec_and_test(cnt)) {
+		/* when we actually did the dec, we didn't hit 0 */
+		mutex_unlock(lock);
+		return 0;
+	}
+	/* we hit 0, and we hold the lock */
+	return 1;
+}
+EXPORT_SYMBOL(atomic_dec_and_mutex_lock);
@ kernel/locking/rtmutex-debug.c:35 @
 
 #include "rtmutex_common.h"
 
-static void printk_task(struct task_struct *p)
-{
-	if (p)
-		printk("%16s:%5d [%p, %3d]", p->comm, task_pid_nr(p), p, p->prio);
-	else
-		printk("<none>");
-}
-
-static void printk_lock(struct rt_mutex *lock, int print_owner)
-{
-	if (lock->name)
-		printk(" [%p] {%s}\n",
-			lock, lock->name);
-	else
-		printk(" [%p] {%s:%d}\n",
-			lock, lock->file, lock->line);
-
-	if (print_owner && rt_mutex_owner(lock)) {
-		printk(".. ->owner: %p\n", lock->owner);
-		printk(".. held by:  ");
-		printk_task(rt_mutex_owner(lock));
-		printk("\n");
-	}
-}
-
 void rt_mutex_debug_task_free(struct task_struct *task)
 {
 	DEBUG_LOCKS_WARN_ON(!RB_EMPTY_ROOT(&task->pi_waiters.rb_root));
 	DEBUG_LOCKS_WARN_ON(task->pi_blocked_on);
 }
 
-/*
- * We fill out the fields in the waiter to store the information about
- * the deadlock. We print when we return. act_waiter can be NULL in
- * case of a remove waiter operation.
- */
-void debug_rt_mutex_deadlock(enum rtmutex_chainwalk chwalk,
-			     struct rt_mutex_waiter *act_waiter,
-			     struct rt_mutex *lock)
-{
-	struct task_struct *task;
-
-	if (!debug_locks || chwalk == RT_MUTEX_FULL_CHAINWALK || !act_waiter)
-		return;
-
-	task = rt_mutex_owner(act_waiter->lock);
-	if (task && task != current) {
-		act_waiter->deadlock_task_pid = get_pid(task_pid(task));
-		act_waiter->deadlock_lock = lock;
-	}
-}
-
-void debug_rt_mutex_print_deadlock(struct rt_mutex_waiter *waiter)
-{
-	struct task_struct *task;
-
-	if (!waiter->deadlock_lock || !debug_locks)
-		return;
-
-	rcu_read_lock();
-	task = pid_task(waiter->deadlock_task_pid, PIDTYPE_PID);
-	if (!task) {
-		rcu_read_unlock();
-		return;
-	}
-
-	if (!debug_locks_off()) {
-		rcu_read_unlock();
-		return;
-	}
-
-	pr_warn("\n");
-	pr_warn("============================================\n");
-	pr_warn("WARNING: circular locking deadlock detected!\n");
-	pr_warn("%s\n", print_tainted());
-	pr_warn("--------------------------------------------\n");
-	printk("%s/%d is deadlocking current task %s/%d\n\n",
-	       task->comm, task_pid_nr(task),
-	       current->comm, task_pid_nr(current));
-
-	printk("\n1) %s/%d is trying to acquire this lock:\n",
-	       current->comm, task_pid_nr(current));
-	printk_lock(waiter->lock, 1);
-
-	printk("\n2) %s/%d is blocked on this lock:\n",
-		task->comm, task_pid_nr(task));
-	printk_lock(waiter->deadlock_lock, 1);
-
-	debug_show_held_locks(current);
-	debug_show_held_locks(task);
-
-	printk("\n%s/%d's [blocked] stackdump:\n\n",
-		task->comm, task_pid_nr(task));
-	show_stack(task, NULL, KERN_DEFAULT);
-	printk("\n%s/%d's [current] stackdump:\n\n",
-		current->comm, task_pid_nr(current));
-	dump_stack();
-	debug_show_all_locks();
-	rcu_read_unlock();
-
-	printk("[ turning off deadlock detection."
-	       "Please report this trace. ]\n\n");
-}
-
 void debug_rt_mutex_lock(struct rt_mutex *lock)
 {
 }
@ kernel/locking/rtmutex-debug.c:63 @ void debug_rt_mutex_proxy_unlock(struct rt_mutex *lock)
 void debug_rt_mutex_init_waiter(struct rt_mutex_waiter *waiter)
 {
 	memset(waiter, 0x11, sizeof(*waiter));
-	waiter->deadlock_task_pid = NULL;
 }
 
 void debug_rt_mutex_free_waiter(struct rt_mutex_waiter *waiter)
 {
-	put_pid(waiter->deadlock_task_pid);
 	memset(waiter, 0x22, sizeof(*waiter));
 }
 
@ kernel/locking/rtmutex-debug.c:76 @ void debug_rt_mutex_init(struct rt_mutex *lock, const char *name, struct lock_cl
 	 * Make sure we are not reinitializing a held lock:
 	 */
 	debug_check_no_locks_freed((void *)lock, sizeof(*lock));
-	lock->name = name;
 
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 	lockdep_init_map(&lock->dep_map, name, key, 0);
 #endif
 }
-
@ kernel/locking/rtmutex-debug.h:21 @ extern void debug_rt_mutex_unlock(struct rt_mutex *lock);
 extern void debug_rt_mutex_proxy_lock(struct rt_mutex *lock,
 				      struct task_struct *powner);
 extern void debug_rt_mutex_proxy_unlock(struct rt_mutex *lock);
-extern void debug_rt_mutex_deadlock(enum rtmutex_chainwalk chwalk,
-				    struct rt_mutex_waiter *waiter,
-				    struct rt_mutex *lock);
-extern void debug_rt_mutex_print_deadlock(struct rt_mutex_waiter *waiter);
-# define debug_rt_mutex_reset_waiter(w)			\
-	do { (w)->deadlock_lock = NULL; } while (0)
 
 static inline bool debug_rt_mutex_detect_deadlock(struct rt_mutex_waiter *waiter,
 						  enum rtmutex_chainwalk walk)
 {
 	return (waiter != NULL);
 }
-
-static inline void rt_mutex_print_deadlock(struct rt_mutex_waiter *w)
-{
-	debug_rt_mutex_print_deadlock(w);
-}
@ kernel/locking/rtmutex.c:11 @
  *  Copyright (C) 2005-2006 Timesys Corp., Thomas Gleixner <tglx@timesys.com>
  *  Copyright (C) 2005 Kihon Technologies Inc., Steven Rostedt
  *  Copyright (C) 2006 Esben Nielsen
+ * Adaptive Spinlocks:
+ *  Copyright (C) 2008 Novell, Inc., Gregory Haskins, Sven Dietrich,
+ *				     and Peter Morreale,
+ * Adaptive Spinlocks simplification:
+ *  Copyright (C) 2008 Red Hat, Inc., Steven Rostedt <srostedt@redhat.com>
  *
  *  See Documentation/locking/rt-mutex-design.rst for details.
  */
@ kernel/locking/rtmutex.c:27 @
 #include <linux/sched/wake_q.h>
 #include <linux/sched/debug.h>
 #include <linux/timer.h>
+#include <linux/ww_mutex.h>
 
 #include "rtmutex_common.h"
 
@ kernel/locking/rtmutex.c:145 @ static void fixup_rt_mutex_waiters(struct rt_mutex *lock)
 		WRITE_ONCE(*p, owner & ~RT_MUTEX_HAS_WAITERS);
 }
 
+static int rt_mutex_real_waiter(struct rt_mutex_waiter *waiter)
+{
+	return waiter && waiter != PI_WAKEUP_INPROGRESS &&
+		waiter != PI_REQUEUE_INPROGRESS;
+}
+
 /*
  * We can speed up the acquire/release, if there's no debugging state to be
  * set up.
@ kernel/locking/rtmutex.c:242 @ static inline bool unlock_rt_mutex_safe(struct rt_mutex *lock,
  * Only use with rt_mutex_waiter_{less,equal}()
  */
 #define task_to_waiter(p)	\
-	&(struct rt_mutex_waiter){ .prio = (p)->prio, .deadline = (p)->dl.deadline }
+	&(struct rt_mutex_waiter){ .prio = (p)->prio, .deadline = (p)->dl.deadline, .task = (p) }
 
 static inline int
 rt_mutex_waiter_less(struct rt_mutex_waiter *left,
@ kernel/locking/rtmutex.c:282 @ rt_mutex_waiter_equal(struct rt_mutex_waiter *left,
 	return 1;
 }
 
+#define STEAL_NORMAL  0
+#define STEAL_LATERAL 1
+
+static inline int
+rt_mutex_steal(struct rt_mutex *lock, struct rt_mutex_waiter *waiter, int mode)
+{
+	struct rt_mutex_waiter *top_waiter = rt_mutex_top_waiter(lock);
+
+	if (waiter == top_waiter || rt_mutex_waiter_less(waiter, top_waiter))
+		return 1;
+
+	/*
+	 * Note that RT tasks are excluded from lateral-steals
+	 * to prevent the introduction of an unbounded latency.
+	 */
+	if (mode == STEAL_NORMAL || rt_task(waiter->task))
+		return 0;
+
+	return rt_mutex_waiter_equal(waiter, top_waiter);
+}
+
 static void
 rt_mutex_enqueue(struct rt_mutex *lock, struct rt_mutex_waiter *waiter)
 {
@ kernel/locking/rtmutex.c:407 @ static bool rt_mutex_cond_detect_deadlock(struct rt_mutex_waiter *waiter,
 	return debug_rt_mutex_detect_deadlock(waiter, chwalk);
 }
 
+static void rt_mutex_wake_waiter(struct rt_mutex_waiter *waiter)
+{
+	if (waiter->savestate)
+		wake_up_lock_sleeper(waiter->task);
+	else
+		wake_up_process(waiter->task);
+}
+
 /*
  * Max number of times we'll walk the boosting chain:
  */
@ kernel/locking/rtmutex.c:422 @ int max_lock_depth = 1024;
 
 static inline struct rt_mutex *task_blocked_on_lock(struct task_struct *p)
 {
-	return p->pi_blocked_on ? p->pi_blocked_on->lock : NULL;
+	return rt_mutex_real_waiter(p->pi_blocked_on) ?
+		p->pi_blocked_on->lock : NULL;
 }
 
 /*
@ kernel/locking/rtmutex.c:559 @ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
 	 * reached or the state of the chain has changed while we
 	 * dropped the locks.
 	 */
-	if (!waiter)
+	if (!rt_mutex_real_waiter(waiter))
 		goto out_unlock_pi;
 
 	/*
@ kernel/locking/rtmutex.c:642 @ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
 	 * walk, we detected a deadlock.
 	 */
 	if (lock == orig_lock || rt_mutex_owner(lock) == top_task) {
-		debug_rt_mutex_deadlock(chwalk, orig_waiter, lock);
 		raw_spin_unlock(&lock->wait_lock);
 		ret = -EDEADLK;
 		goto out_unlock_pi;
@ kernel/locking/rtmutex.c:738 @ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
 	 * follow here. This is the end of the chain we are walking.
 	 */
 	if (!rt_mutex_owner(lock)) {
+		struct rt_mutex_waiter *lock_top_waiter;
+
 		/*
 		 * If the requeue [7] above changed the top waiter,
 		 * then we need to wake the new top waiter up to try
 		 * to get the lock.
 		 */
-		if (prerequeue_top_waiter != rt_mutex_top_waiter(lock))
-			wake_up_process(rt_mutex_top_waiter(lock)->task);
+		lock_top_waiter = rt_mutex_top_waiter(lock);
+		if (prerequeue_top_waiter != lock_top_waiter)
+			rt_mutex_wake_waiter(lock_top_waiter);
 		raw_spin_unlock_irq(&lock->wait_lock);
 		return 0;
 	}
@ kernel/locking/rtmutex.c:848 @ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
  * @task:   The task which wants to acquire the lock
  * @waiter: The waiter that is queued to the lock's wait tree if the
  *	    callsite called task_blocked_on_lock(), otherwise NULL
+ * @mode:   Lock steal mode (STEAL_NORMAL, STEAL_LATERAL)
  */
-static int try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
-				struct rt_mutex_waiter *waiter)
+static int __try_to_take_rt_mutex(struct rt_mutex *lock,
+				  struct task_struct *task,
+				  struct rt_mutex_waiter *waiter, int mode)
 {
 	lockdep_assert_held(&lock->wait_lock);
 
@ kernel/locking/rtmutex.c:888 @ static int try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
 	 */
 	if (waiter) {
 		/*
-		 * If waiter is not the highest priority waiter of
-		 * @lock, give up.
+		 * If waiter is not the highest priority waiter of @lock,
+		 * or its peer when lateral steal is allowed, give up.
 		 */
-		if (waiter != rt_mutex_top_waiter(lock))
+		if (!rt_mutex_steal(lock, waiter, mode))
 			return 0;
-
 		/*
 		 * We can acquire the lock. Remove the waiter from the
 		 * lock waiters tree.
@ kernel/locking/rtmutex.c:910 @ static int try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
 		 */
 		if (rt_mutex_has_waiters(lock)) {
 			/*
-			 * If @task->prio is greater than or equal to
-			 * the top waiter priority (kernel view),
-			 * @task lost.
+			 * If @task->prio is greater than the top waiter
+			 * priority (kernel view), or equal to it when a
+			 * lateral steal is forbidden, @task lost.
 			 */
-			if (!rt_mutex_waiter_less(task_to_waiter(task),
-						  rt_mutex_top_waiter(lock)))
+			if (!rt_mutex_steal(lock, task_to_waiter(task), mode))
 				return 0;
-
 			/*
 			 * The current top waiter stays enqueued. We
 			 * don't have to change anything in the lock
@ kernel/locking/rtmutex.c:962 @ static int try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
 	return 1;
 }
 
+#ifdef CONFIG_PREEMPT_RT
+/*
+ * preemptible spin_lock functions:
+ */
+static inline void rt_spin_lock_fastlock(struct rt_mutex *lock,
+					 void  (*slowfn)(struct rt_mutex *lock))
+{
+	might_sleep_no_state_check();
+
+	if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current)))
+		return;
+	else
+		slowfn(lock);
+}
+
+static inline void rt_spin_lock_fastunlock(struct rt_mutex *lock,
+					   void  (*slowfn)(struct rt_mutex *lock))
+{
+	if (likely(rt_mutex_cmpxchg_release(lock, current, NULL)))
+		return;
+	else
+		slowfn(lock);
+}
+#ifdef CONFIG_SMP
+/*
+ * Note that owner is a speculative pointer and dereferencing relies
+ * on rcu_read_lock() and the check against the lock owner.
+ */
+static int adaptive_wait(struct rt_mutex *lock,
+			 struct task_struct *owner)
+{
+	int res = 0;
+
+	rcu_read_lock();
+	for (;;) {
+		if (owner != rt_mutex_owner(lock))
+			break;
+		/*
+		 * Ensure that owner->on_cpu is dereferenced _after_
+		 * checking the above to be valid.
+		 */
+		barrier();
+		if (!owner->on_cpu) {
+			res = 1;
+			break;
+		}
+		cpu_relax();
+	}
+	rcu_read_unlock();
+	return res;
+}
+#else
+static int adaptive_wait(struct rt_mutex *lock,
+			 struct task_struct *orig_owner)
+{
+	return 1;
+}
+#endif
+
+static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
+				   struct rt_mutex_waiter *waiter,
+				   struct task_struct *task,
+				   enum rtmutex_chainwalk chwalk);
+/*
+ * Slow path lock function spin_lock style: this variant is very
+ * careful not to miss any non-lock wakeups.
+ *
+ * We store the current state under p->pi_lock in p->saved_state and
+ * the try_to_wake_up() code handles this accordingly.
+ */
+void __sched rt_spin_lock_slowlock_locked(struct rt_mutex *lock,
+					  struct rt_mutex_waiter *waiter,
+					  unsigned long flags)
+{
+	struct task_struct *lock_owner, *self = current;
+	struct rt_mutex_waiter *top_waiter;
+	int ret;
+
+	if (__try_to_take_rt_mutex(lock, self, NULL, STEAL_LATERAL))
+		return;
+
+	BUG_ON(rt_mutex_owner(lock) == self);
+
+	/*
+	 * We save whatever state the task is in and we'll restore it
+	 * after acquiring the lock taking real wakeups into account
+	 * as well. We are serialized via pi_lock against wakeups. See
+	 * try_to_wake_up().
+	 */
+	raw_spin_lock(&self->pi_lock);
+	self->saved_state = self->state;
+	__set_current_state_no_track(TASK_UNINTERRUPTIBLE);
+	raw_spin_unlock(&self->pi_lock);
+
+	ret = task_blocks_on_rt_mutex(lock, waiter, self, RT_MUTEX_MIN_CHAINWALK);
+	BUG_ON(ret);
+
+	for (;;) {
+		/* Try to acquire the lock again. */
+		if (__try_to_take_rt_mutex(lock, self, waiter, STEAL_LATERAL))
+			break;
+
+		top_waiter = rt_mutex_top_waiter(lock);
+		lock_owner = rt_mutex_owner(lock);
+
+		raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
+
+		if (top_waiter != waiter || adaptive_wait(lock, lock_owner))
+			preempt_schedule_lock();
+
+		raw_spin_lock_irqsave(&lock->wait_lock, flags);
+
+		raw_spin_lock(&self->pi_lock);
+		__set_current_state_no_track(TASK_UNINTERRUPTIBLE);
+		raw_spin_unlock(&self->pi_lock);
+	}
+
+	/*
+	 * Restore the task state to current->saved_state. We set it
+	 * to the original state above and the try_to_wake_up() code
+	 * has possibly updated it when a real (non-rtmutex) wakeup
+	 * happened while we were blocked. Clear saved_state so
+	 * try_to_wakeup() does not get confused.
+	 */
+	raw_spin_lock(&self->pi_lock);
+	__set_current_state_no_track(self->saved_state);
+	self->saved_state = TASK_RUNNING;
+	raw_spin_unlock(&self->pi_lock);
+
+	/*
+	 * try_to_take_rt_mutex() sets the waiter bit
+	 * unconditionally. We might have to fix that up:
+	 */
+	fixup_rt_mutex_waiters(lock);
+
+	BUG_ON(rt_mutex_has_waiters(lock) && waiter == rt_mutex_top_waiter(lock));
+	BUG_ON(!RB_EMPTY_NODE(&waiter->tree_entry));
+}
+
+static void noinline __sched rt_spin_lock_slowlock(struct rt_mutex *lock)
+{
+	struct rt_mutex_waiter waiter;
+	unsigned long flags;
+
+	rt_mutex_init_waiter(&waiter, true);
+
+	raw_spin_lock_irqsave(&lock->wait_lock, flags);
+	rt_spin_lock_slowlock_locked(lock, &waiter, flags);
+	raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
+	debug_rt_mutex_free_waiter(&waiter);
+}
+
+static bool __sched __rt_mutex_unlock_common(struct rt_mutex *lock,
+					     struct wake_q_head *wake_q,
+					     struct wake_q_head *wq_sleeper);
+/*
+ * Slow path to release a rt_mutex spin_lock style
+ */
+void __sched rt_spin_lock_slowunlock(struct rt_mutex *lock)
+{
+	unsigned long flags;
+	DEFINE_WAKE_Q(wake_q);
+	DEFINE_WAKE_Q(wake_sleeper_q);
+	bool postunlock;
+
+	raw_spin_lock_irqsave(&lock->wait_lock, flags);
+	postunlock = __rt_mutex_unlock_common(lock, &wake_q, &wake_sleeper_q);
+	raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
+
+	if (postunlock)
+		rt_mutex_postunlock(&wake_q, &wake_sleeper_q);
+}
+
+void __lockfunc rt_spin_lock(spinlock_t *lock)
+{
+	spin_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+	rt_spin_lock_fastlock(&lock->lock, rt_spin_lock_slowlock);
+	rcu_read_lock();
+	migrate_disable();
+}
+EXPORT_SYMBOL(rt_spin_lock);
+
+void __lockfunc __rt_spin_lock(struct rt_mutex *lock)
+{
+	rt_spin_lock_fastlock(lock, rt_spin_lock_slowlock);
+}
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+void __lockfunc rt_spin_lock_nested(spinlock_t *lock, int subclass)
+{
+	spin_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
+	rt_spin_lock_fastlock(&lock->lock, rt_spin_lock_slowlock);
+	rcu_read_lock();
+	migrate_disable();
+}
+EXPORT_SYMBOL(rt_spin_lock_nested);
+
+void __lockfunc rt_spin_lock_nest_lock(spinlock_t *lock,
+				       struct lockdep_map *nest_lock)
+{
+	spin_acquire_nest(&lock->dep_map, 0, 0, nest_lock, _RET_IP_);
+	rt_spin_lock_fastlock(&lock->lock, rt_spin_lock_slowlock);
+	rcu_read_lock();
+	migrate_disable();
+}
+EXPORT_SYMBOL(rt_spin_lock_nest_lock);
+#endif
+
+void __lockfunc rt_spin_unlock(spinlock_t *lock)
+{
+	/* NOTE: we always pass in '1' for nested, for simplicity */
+	spin_release(&lock->dep_map, _RET_IP_);
+	migrate_enable();
+	rcu_read_unlock();
+	rt_spin_lock_fastunlock(&lock->lock, rt_spin_lock_slowunlock);
+}
+EXPORT_SYMBOL(rt_spin_unlock);
+
+void __lockfunc __rt_spin_unlock(struct rt_mutex *lock)
+{
+	rt_spin_lock_fastunlock(lock, rt_spin_lock_slowunlock);
+}
+EXPORT_SYMBOL(__rt_spin_unlock);
+
+/*
+ * Wait for the lock to get unlocked: instead of polling for an unlock
+ * (like raw spinlocks do), we lock and unlock, to force the kernel to
+ * schedule if there's contention:
+ */
+void __lockfunc rt_spin_lock_unlock(spinlock_t *lock)
+{
+	spin_lock(lock);
+	spin_unlock(lock);
+}
+EXPORT_SYMBOL(rt_spin_lock_unlock);
+
+int __lockfunc rt_spin_trylock(spinlock_t *lock)
+{
+	int ret;
+
+	ret = __rt_mutex_trylock(&lock->lock);
+	if (ret) {
+		spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
+		rcu_read_lock();
+		migrate_disable();
+	}
+	return ret;
+}
+EXPORT_SYMBOL(rt_spin_trylock);
+
+int __lockfunc rt_spin_trylock_bh(spinlock_t *lock)
+{
+	int ret;
+
+	local_bh_disable();
+	ret = __rt_mutex_trylock(&lock->lock);
+	if (ret) {
+		spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
+		rcu_read_lock();
+		migrate_disable();
+	} else {
+		local_bh_enable();
+	}
+	return ret;
+}
+EXPORT_SYMBOL(rt_spin_trylock_bh);
+
+void
+__rt_spin_lock_init(spinlock_t *lock, const char *name, struct lock_class_key *key)
+{
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+	/*
+	 * Make sure we are not reinitializing a held lock:
+	 */
+	debug_check_no_locks_freed((void *)lock, sizeof(*lock));
+	lockdep_init_map(&lock->dep_map, name, key, 0);
+#endif
+}
+EXPORT_SYMBOL(__rt_spin_lock_init);
+
+#endif /* PREEMPT_RT */
+
+#ifdef CONFIG_PREEMPT_RT
+	static inline int __sched
+__mutex_lock_check_stamp(struct rt_mutex *lock, struct ww_acquire_ctx *ctx)
+{
+	struct ww_mutex *ww = container_of(lock, struct ww_mutex, base.lock);
+	struct ww_acquire_ctx *hold_ctx = READ_ONCE(ww->ctx);
+
+	if (!hold_ctx)
+		return 0;
+
+	if (unlikely(ctx == hold_ctx))
+		return -EALREADY;
+
+	if (ctx->stamp - hold_ctx->stamp <= LONG_MAX &&
+	    (ctx->stamp != hold_ctx->stamp || ctx > hold_ctx)) {
+#ifdef CONFIG_DEBUG_MUTEXES
+		DEBUG_LOCKS_WARN_ON(ctx->contending_lock);
+		ctx->contending_lock = ww;
+#endif
+		return -EDEADLK;
+	}
+
+	return 0;
+}
+#else
+	static inline int __sched
+__mutex_lock_check_stamp(struct rt_mutex *lock, struct ww_acquire_ctx *ctx)
+{
+	BUG();
+	return 0;
+}
+
+#endif
+
+static inline int
+try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
+		     struct rt_mutex_waiter *waiter)
+{
+	return __try_to_take_rt_mutex(lock, task, waiter, STEAL_NORMAL);
+}
+
 /*
  * Task blocks on lock.
  *
@ kernel/locking/rtmutex.c:1317 @ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
 		return -EDEADLK;
 
 	raw_spin_lock(&task->pi_lock);
+	/*
+	 * In the case of futex requeue PI, this will be a proxy
+	 * lock. The task will wake unaware that it is enqueueed on
+	 * this lock. Avoid blocking on two locks and corrupting
+	 * pi_blocked_on via the PI_WAKEUP_INPROGRESS
+	 * flag. futex_wait_requeue_pi() sets this when it wakes up
+	 * before requeue (due to a signal or timeout). Do not enqueue
+	 * the task if PI_WAKEUP_INPROGRESS is set.
+	 */
+	if (task != current && task->pi_blocked_on == PI_WAKEUP_INPROGRESS) {
+		raw_spin_unlock(&task->pi_lock);
+		return -EAGAIN;
+	}
+
+       BUG_ON(rt_mutex_real_waiter(task->pi_blocked_on));
+
 	waiter->task = task;
 	waiter->lock = lock;
 	waiter->prio = task->prio;
@ kernel/locking/rtmutex.c:1356 @ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
 		rt_mutex_enqueue_pi(owner, waiter);
 
 		rt_mutex_adjust_prio(owner);
-		if (owner->pi_blocked_on)
+		if (rt_mutex_real_waiter(owner->pi_blocked_on))
 			chain_walk = 1;
 	} else if (rt_mutex_cond_detect_deadlock(waiter, chwalk)) {
 		chain_walk = 1;
@ kernel/locking/rtmutex.c:1398 @ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
  * Called with lock->wait_lock held and interrupts disabled.
  */
 static void mark_wakeup_next_waiter(struct wake_q_head *wake_q,
+				    struct wake_q_head *wake_sleeper_q,
 				    struct rt_mutex *lock)
 {
 	struct rt_mutex_waiter *waiter;
@ kernel/locking/rtmutex.c:1438 @ static void mark_wakeup_next_waiter(struct wake_q_head *wake_q,
 	 * Pairs with preempt_enable() in rt_mutex_postunlock();
 	 */
 	preempt_disable();
-	wake_q_add(wake_q, waiter->task);
+	if (waiter->savestate)
+		wake_q_add_sleeper(wake_sleeper_q, waiter->task);
+	else
+		wake_q_add(wake_q, waiter->task);
 	raw_spin_unlock(&current->pi_lock);
 }
 
@ kernel/locking/rtmutex.c:1456 @ static void remove_waiter(struct rt_mutex *lock,
 {
 	bool is_top_waiter = (waiter == rt_mutex_top_waiter(lock));
 	struct task_struct *owner = rt_mutex_owner(lock);
-	struct rt_mutex *next_lock;
+	struct rt_mutex *next_lock = NULL;
 
 	lockdep_assert_held(&lock->wait_lock);
 
@ kernel/locking/rtmutex.c:1482 @ static void remove_waiter(struct rt_mutex *lock,
 	rt_mutex_adjust_prio(owner);
 
 	/* Store the lock on which owner is blocked or NULL */
-	next_lock = task_blocked_on_lock(owner);
+	if (rt_mutex_real_waiter(owner->pi_blocked_on))
+		next_lock = task_blocked_on_lock(owner);
 
 	raw_spin_unlock(&owner->pi_lock);
 
@ kernel/locking/rtmutex.c:1519 @ void rt_mutex_adjust_pi(struct task_struct *task)
 	raw_spin_lock_irqsave(&task->pi_lock, flags);
 
 	waiter = task->pi_blocked_on;
-	if (!waiter || rt_mutex_waiter_equal(waiter, task_to_waiter(task))) {
+	if (!rt_mutex_real_waiter(waiter) ||
+	    rt_mutex_waiter_equal(waiter, task_to_waiter(task))) {
 		raw_spin_unlock_irqrestore(&task->pi_lock, flags);
 		return;
 	}
 	next_lock = waiter->lock;
-	raw_spin_unlock_irqrestore(&task->pi_lock, flags);
 
 	/* gets dropped in rt_mutex_adjust_prio_chain()! */
 	get_task_struct(task);
 
+	raw_spin_unlock_irqrestore(&task->pi_lock, flags);
 	rt_mutex_adjust_prio_chain(task, RT_MUTEX_MIN_CHAINWALK, NULL,
 				   next_lock, NULL, task);
 }
 
-void rt_mutex_init_waiter(struct rt_mutex_waiter *waiter)
+void rt_mutex_init_waiter(struct rt_mutex_waiter *waiter, bool savestate)
 {
 	debug_rt_mutex_init_waiter(waiter);
 	RB_CLEAR_NODE(&waiter->pi_tree_entry);
 	RB_CLEAR_NODE(&waiter->tree_entry);
 	waiter->task = NULL;
+	waiter->savestate = savestate;
 }
 
 /**
@ kernel/locking/rtmutex.c:1556 @ void rt_mutex_init_waiter(struct rt_mutex_waiter *waiter)
 static int __sched
 __rt_mutex_slowlock(struct rt_mutex *lock, int state,
 		    struct hrtimer_sleeper *timeout,
-		    struct rt_mutex_waiter *waiter)
+		    struct rt_mutex_waiter *waiter,
+		    struct ww_acquire_ctx *ww_ctx)
 {
 	int ret = 0;
 
@ kernel/locking/rtmutex.c:1566 @ __rt_mutex_slowlock(struct rt_mutex *lock, int state,
 		if (try_to_take_rt_mutex(lock, current, waiter))
 			break;
 
-		/*
-		 * TASK_INTERRUPTIBLE checks for signals and
-		 * timeout. Ignored otherwise.
-		 */
-		if (likely(state == TASK_INTERRUPTIBLE)) {
-			/* Signal pending? */
-			if (signal_pending(current))
-				ret = -EINTR;
-			if (timeout && !timeout->task)
-				ret = -ETIMEDOUT;
+		if (timeout && !timeout->task) {
+			ret = -ETIMEDOUT;
+			break;
+		}
+		if (signal_pending_state(state, current)) {
+			ret = -EINTR;
+			break;
+		}
+
+		if (ww_ctx && ww_ctx->acquired > 0) {
+			ret = __mutex_lock_check_stamp(lock, ww_ctx);
 			if (ret)
 				break;
 		}
 
 		raw_spin_unlock_irq(&lock->wait_lock);
 
-		debug_rt_mutex_print_deadlock(waiter);
-
 		schedule();
 
 		raw_spin_lock_irq(&lock->wait_lock);
@ kernel/locking/rtmutex.c:1603 @ static void rt_mutex_handle_deadlock(int res, int detect_deadlock,
 	if (res != -EDEADLOCK || detect_deadlock)
 		return;
 
-	/*
-	 * Yell lowdly and stop the task right here.
-	 */
-	rt_mutex_print_deadlock(w);
 	while (1) {
 		set_current_state(TASK_INTERRUPTIBLE);
 		schedule();
 	}
 }
 
-/*
- * Slow path lock function:
- */
-static int __sched
-rt_mutex_slowlock(struct rt_mutex *lock, int state,
-		  struct hrtimer_sleeper *timeout,
-		  enum rtmutex_chainwalk chwalk)
+static __always_inline void ww_mutex_lock_acquired(struct ww_mutex *ww,
+						   struct ww_acquire_ctx *ww_ctx)
 {
-	struct rt_mutex_waiter waiter;
-	unsigned long flags;
-	int ret = 0;
+#ifdef CONFIG_DEBUG_MUTEXES
+	/*
+	 * If this WARN_ON triggers, you used ww_mutex_lock to acquire,
+	 * but released with a normal mutex_unlock in this call.
+	 *
+	 * This should never happen, always use ww_mutex_unlock.
+	 */
+	DEBUG_LOCKS_WARN_ON(ww->ctx);
+
+	/*
+	 * Not quite done after calling ww_acquire_done() ?
+	 */
+	DEBUG_LOCKS_WARN_ON(ww_ctx->done_acquire);
 
-	rt_mutex_init_waiter(&waiter);
+	if (ww_ctx->contending_lock) {
+		/*
+		 * After -EDEADLK you tried to
+		 * acquire a different ww_mutex? Bad!
+		 */
+		DEBUG_LOCKS_WARN_ON(ww_ctx->contending_lock != ww);
+
+		/*
+		 * You called ww_mutex_lock after receiving -EDEADLK,
+		 * but 'forgot' to unlock everything else first?
+		 */
+		DEBUG_LOCKS_WARN_ON(ww_ctx->acquired > 0);
+		ww_ctx->contending_lock = NULL;
+	}
 
 	/*
-	 * Technically we could use raw_spin_[un]lock_irq() here, but this can
-	 * be called in early boot if the cmpxchg() fast path is disabled
-	 * (debug, no architecture support). In this case we will acquire the
-	 * rtmutex with lock->wait_lock held. But we cannot unconditionally
-	 * enable interrupts in that early boot case. So we need to use the
-	 * irqsave/restore variants.
+	 * Naughty, using a different class will lead to undefined behavior!
 	 */
-	raw_spin_lock_irqsave(&lock->wait_lock, flags);
+	DEBUG_LOCKS_WARN_ON(ww_ctx->ww_class != ww->ww_class);
+#endif
+	ww_ctx->acquired++;
+}
+
+#ifdef CONFIG_PREEMPT_RT
+static void ww_mutex_account_lock(struct rt_mutex *lock,
+				  struct ww_acquire_ctx *ww_ctx)
+{
+	struct ww_mutex *ww = container_of(lock, struct ww_mutex, base.lock);
+	struct rt_mutex_waiter *waiter, *n;
+
+	/*
+	 * This branch gets optimized out for the common case,
+	 * and is only important for ww_mutex_lock.
+	 */
+	ww_mutex_lock_acquired(ww, ww_ctx);
+	ww->ctx = ww_ctx;
+
+	/*
+	 * Give any possible sleeping processes the chance to wake up,
+	 * so they can recheck if they have to back off.
+	 */
+	rbtree_postorder_for_each_entry_safe(waiter, n, &lock->waiters.rb_root,
+					     tree_entry) {
+		/* XXX debug rt mutex waiter wakeup */
+
+		BUG_ON(waiter->lock != lock);
+		rt_mutex_wake_waiter(waiter);
+	}
+}
+
+#else
+
+static void ww_mutex_account_lock(struct rt_mutex *lock,
+				  struct ww_acquire_ctx *ww_ctx)
+{
+	BUG();
+}
+#endif
+
+int __sched rt_mutex_slowlock_locked(struct rt_mutex *lock, int state,
+				     struct hrtimer_sleeper *timeout,
+				     enum rtmutex_chainwalk chwalk,
+				     struct ww_acquire_ctx *ww_ctx,
+				     struct rt_mutex_waiter *waiter)
+{
+	int ret;
+
+#ifdef CONFIG_PREEMPT_RT
+	if (ww_ctx) {
+		struct ww_mutex *ww;
+
+		ww = container_of(lock, struct ww_mutex, base.lock);
+		if (unlikely(ww_ctx == READ_ONCE(ww->ctx)))
+			return -EALREADY;
+	}
+#endif
 
 	/* Try to acquire the lock again: */
 	if (try_to_take_rt_mutex(lock, current, NULL)) {
-		raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
+		if (ww_ctx)
+			ww_mutex_account_lock(lock, ww_ctx);
 		return 0;
 	}
 
@ kernel/locking/rtmutex.c:1716 @ rt_mutex_slowlock(struct rt_mutex *lock, int state,
 	if (unlikely(timeout))
 		hrtimer_start_expires(&timeout->timer, HRTIMER_MODE_ABS);
 
-	ret = task_blocks_on_rt_mutex(lock, &waiter, current, chwalk);
+	ret = task_blocks_on_rt_mutex(lock, waiter, current, chwalk);
 
-	if (likely(!ret))
+	if (likely(!ret)) {
 		/* sleep on the mutex */
-		ret = __rt_mutex_slowlock(lock, state, timeout, &waiter);
+		ret = __rt_mutex_slowlock(lock, state, timeout, waiter,
+					  ww_ctx);
+	} else if (ww_ctx) {
+		/* ww_mutex received EDEADLK, let it become EALREADY */
+		ret = __mutex_lock_check_stamp(lock, ww_ctx);
+		BUG_ON(!ret);
+	}
 
 	if (unlikely(ret)) {
 		__set_current_state(TASK_RUNNING);
-		remove_waiter(lock, &waiter);
-		rt_mutex_handle_deadlock(ret, chwalk, &waiter);
+		remove_waiter(lock, waiter);
+		/* ww_mutex wants to report EDEADLK/EALREADY, let it */
+		if (!ww_ctx)
+			rt_mutex_handle_deadlock(ret, chwalk, waiter);
+	} else if (ww_ctx) {
+		ww_mutex_account_lock(lock, ww_ctx);
 	}
 
 	/*
@ kernel/locking/rtmutex.c:1743 @ rt_mutex_slowlock(struct rt_mutex *lock, int state,
 	 * unconditionally. We might have to fix that up.
 	 */
 	fixup_rt_mutex_waiters(lock);
+	return ret;
+}
+
+/*
+ * Slow path lock function:
+ */
+static int __sched
+rt_mutex_slowlock(struct rt_mutex *lock, int state,
+		  struct hrtimer_sleeper *timeout,
+		  enum rtmutex_chainwalk chwalk,
+		  struct ww_acquire_ctx *ww_ctx)
+{
+	struct rt_mutex_waiter waiter;
+	unsigned long flags;
+	int ret = 0;
+
+	rt_mutex_init_waiter(&waiter, false);
+
+	/*
+	 * Technically we could use raw_spin_[un]lock_irq() here, but this can
+	 * be called in early boot if the cmpxchg() fast path is disabled
+	 * (debug, no architecture support). In this case we will acquire the
+	 * rtmutex with lock->wait_lock held. But we cannot unconditionally
+	 * enable interrupts in that early boot case. So we need to use the
+	 * irqsave/restore variants.
+	 */
+	raw_spin_lock_irqsave(&lock->wait_lock, flags);
+
+	ret = rt_mutex_slowlock_locked(lock, state, timeout, chwalk, ww_ctx,
+				       &waiter);
 
 	raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
 
@ kernel/locking/rtmutex.c:1833 @ static inline int rt_mutex_slowtrylock(struct rt_mutex *lock)
  * Return whether the current task needs to call rt_mutex_postunlock().
  */
 static bool __sched rt_mutex_slowunlock(struct rt_mutex *lock,
-					struct wake_q_head *wake_q)
+					struct wake_q_head *wake_q,
+					struct wake_q_head *wake_sleeper_q)
 {
 	unsigned long flags;
 
@ kernel/locking/rtmutex.c:1888 @ static bool __sched rt_mutex_slowunlock(struct rt_mutex *lock,
 	 *
 	 * Queue the next waiter for wakeup once we release the wait_lock.
 	 */
-	mark_wakeup_next_waiter(wake_q, lock);
+	mark_wakeup_next_waiter(wake_q, wake_sleeper_q, lock);
 	raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
 
 	return true; /* call rt_mutex_postunlock() */
@ kernel/locking/rtmutex.c:1902 @ static bool __sched rt_mutex_slowunlock(struct rt_mutex *lock,
  */
 static inline int
 rt_mutex_fastlock(struct rt_mutex *lock, int state,
+		  struct ww_acquire_ctx *ww_ctx,
 		  int (*slowfn)(struct rt_mutex *lock, int state,
 				struct hrtimer_sleeper *timeout,
-				enum rtmutex_chainwalk chwalk))
+				enum rtmutex_chainwalk chwalk,
+				struct ww_acquire_ctx *ww_ctx))
 {
 	if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current)))
 		return 0;
 
-	return slowfn(lock, state, NULL, RT_MUTEX_MIN_CHAINWALK);
-}
-
-static inline int
-rt_mutex_timed_fastlock(struct rt_mutex *lock, int state,
-			struct hrtimer_sleeper *timeout,
-			enum rtmutex_chainwalk chwalk,
-			int (*slowfn)(struct rt_mutex *lock, int state,
-				      struct hrtimer_sleeper *timeout,
-				      enum rtmutex_chainwalk chwalk))
-{
-	if (chwalk == RT_MUTEX_MIN_CHAINWALK &&
-	    likely(rt_mutex_cmpxchg_acquire(lock, NULL, current)))
-		return 0;
-
-	return slowfn(lock, state, timeout, chwalk);
+	return slowfn(lock, state, NULL, RT_MUTEX_MIN_CHAINWALK, ww_ctx);
 }
 
 static inline int
@ kernel/locking/rtmutex.c:1927 @ rt_mutex_fasttrylock(struct rt_mutex *lock,
 /*
  * Performs the wakeup of the the top-waiter and re-enables preemption.
  */
-void rt_mutex_postunlock(struct wake_q_head *wake_q)
+void rt_mutex_postunlock(struct wake_q_head *wake_q,
+			 struct wake_q_head *wake_sleeper_q)
 {
 	wake_up_q(wake_q);
+	wake_up_q_sleeper(wake_sleeper_q);
 
 	/* Pairs with preempt_disable() in rt_mutex_slowunlock() */
 	preempt_enable();
@ kernel/locking/rtmutex.c:1940 @ void rt_mutex_postunlock(struct wake_q_head *wake_q)
 static inline void
 rt_mutex_fastunlock(struct rt_mutex *lock,
 		    bool (*slowfn)(struct rt_mutex *lock,
-				   struct wake_q_head *wqh))
+				   struct wake_q_head *wqh,
+				   struct wake_q_head *wq_sleeper))
 {
 	DEFINE_WAKE_Q(wake_q);
+	DEFINE_WAKE_Q(wake_sleeper_q);
 
 	if (likely(rt_mutex_cmpxchg_release(lock, current, NULL)))
 		return;
 
-	if (slowfn(lock, &wake_q))
-		rt_mutex_postunlock(&wake_q);
+	if (slowfn(lock, &wake_q, &wake_sleeper_q))
+		rt_mutex_postunlock(&wake_q, &wake_sleeper_q);
 }
 
-static inline void __rt_mutex_lock(struct rt_mutex *lock, unsigned int subclass)
+int __sched __rt_mutex_lock_state(struct rt_mutex *lock, int state)
 {
 	might_sleep();
+	return rt_mutex_fastlock(lock, state, NULL, rt_mutex_slowlock);
+}
+
+/**
+ * rt_mutex_lock_state - lock a rt_mutex with a given state
+ *
+ * @lock:      The rt_mutex to be locked
+ * @state:     The state to set when blocking on the rt_mutex
+ */
+static inline int __sched rt_mutex_lock_state(struct rt_mutex *lock,
+					      unsigned int subclass, int state)
+{
+	int ret;
 
 	mutex_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
-	rt_mutex_fastlock(lock, TASK_UNINTERRUPTIBLE, rt_mutex_slowlock);
+	ret = __rt_mutex_lock_state(lock, state);
+	if (ret)
+		mutex_release(&lock->dep_map, _RET_IP_);
+	return ret;
+}
+
+static inline void __rt_mutex_lock(struct rt_mutex *lock, unsigned int subclass)
+{
+	rt_mutex_lock_state(lock, subclass, TASK_UNINTERRUPTIBLE);
 }
 
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
@ kernel/locking/rtmutex.c:2020 @ EXPORT_SYMBOL_GPL(rt_mutex_lock);
  */
 int __sched rt_mutex_lock_interruptible(struct rt_mutex *lock)
 {
-	int ret;
-
-	might_sleep();
-
-	mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
-	ret = rt_mutex_fastlock(lock, TASK_INTERRUPTIBLE, rt_mutex_slowlock);
-	if (ret)
-		mutex_release(&lock->dep_map, _RET_IP_);
-
-	return ret;
+	return rt_mutex_lock_state(lock, 0, TASK_INTERRUPTIBLE);
 }
 EXPORT_SYMBOL_GPL(rt_mutex_lock_interruptible);
 
@ kernel/locking/rtmutex.c:2037 @ int __sched __rt_mutex_futex_trylock(struct rt_mutex *lock)
 	return __rt_mutex_slowtrylock(lock);
 }
 
-/**
- * rt_mutex_timed_lock - lock a rt_mutex interruptible
- *			the timeout structure is provided
- *			by the caller
- *
- * @lock:		the rt_mutex to be locked
- * @timeout:		timeout structure or NULL (no timeout)
- *
- * Returns:
- *  0		on success
- * -EINTR	when interrupted by a signal
- * -ETIMEDOUT	when the timeout expired
- */
-int
-rt_mutex_timed_lock(struct rt_mutex *lock, struct hrtimer_sleeper *timeout)
+int __sched __rt_mutex_trylock(struct rt_mutex *lock)
 {
-	int ret;
-
-	might_sleep();
-
-	mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
-	ret = rt_mutex_timed_fastlock(lock, TASK_INTERRUPTIBLE, timeout,
-				       RT_MUTEX_MIN_CHAINWALK,
-				       rt_mutex_slowlock);
-	if (ret)
-		mutex_release(&lock->dep_map, _RET_IP_);
+#ifdef CONFIG_PREEMPT_RT
+	if (WARN_ON_ONCE(in_irq() || in_nmi()))
+#else
+	if (WARN_ON_ONCE(in_irq() || in_nmi() || in_serving_softirq()))
+#endif
+		return 0;
 
-	return ret;
+	return rt_mutex_fasttrylock(lock, rt_mutex_slowtrylock);
 }
-EXPORT_SYMBOL_GPL(rt_mutex_timed_lock);
 
 /**
  * rt_mutex_trylock - try to lock a rt_mutex
@ kernel/locking/rtmutex.c:2064 @ int __sched rt_mutex_trylock(struct rt_mutex *lock)
 {
 	int ret;
 
-	if (WARN_ON_ONCE(in_irq() || in_nmi() || in_serving_softirq()))
-		return 0;
-
-	ret = rt_mutex_fasttrylock(lock, rt_mutex_slowtrylock);
+	ret = __rt_mutex_trylock(lock);
 	if (ret)
 		mutex_acquire(&lock->dep_map, 0, 1, _RET_IP_);
 
@ kernel/locking/rtmutex.c:2072 @ int __sched rt_mutex_trylock(struct rt_mutex *lock)
 }
 EXPORT_SYMBOL_GPL(rt_mutex_trylock);
 
+void __sched __rt_mutex_unlock(struct rt_mutex *lock)
+{
+	rt_mutex_fastunlock(lock, rt_mutex_slowunlock);
+}
+
 /**
  * rt_mutex_unlock - unlock a rt_mutex
  *
@ kernel/locking/rtmutex.c:2085 @ EXPORT_SYMBOL_GPL(rt_mutex_trylock);
 void __sched rt_mutex_unlock(struct rt_mutex *lock)
 {
 	mutex_release(&lock->dep_map, _RET_IP_);
-	rt_mutex_fastunlock(lock, rt_mutex_slowunlock);
+	__rt_mutex_unlock(lock);
 }
 EXPORT_SYMBOL_GPL(rt_mutex_unlock);
 
-/**
- * Futex variant, that since futex variants do not use the fast-path, can be
- * simple and will not need to retry.
- */
-bool __sched __rt_mutex_futex_unlock(struct rt_mutex *lock,
-				    struct wake_q_head *wake_q)
+static bool __sched __rt_mutex_unlock_common(struct rt_mutex *lock,
+					     struct wake_q_head *wake_q,
+					     struct wake_q_head *wq_sleeper)
 {
 	lockdep_assert_held(&lock->wait_lock);
 
@ kernel/locking/rtmutex.c:2108 @ bool __sched __rt_mutex_futex_unlock(struct rt_mutex *lock,
 	 * avoid inversion prior to the wakeup.  preempt_disable()
 	 * therein pairs with rt_mutex_postunlock().
 	 */
-	mark_wakeup_next_waiter(wake_q, lock);
+	mark_wakeup_next_waiter(wake_q, wq_sleeper, lock);
 
 	return true; /* call postunlock() */
 }
 
+/**
+ * Futex variant, that since futex variants do not use the fast-path, can be
+ * simple and will not need to retry.
+ */
+bool __sched __rt_mutex_futex_unlock(struct rt_mutex *lock,
+				     struct wake_q_head *wake_q,
+				     struct wake_q_head *wq_sleeper)
+{
+	return __rt_mutex_unlock_common(lock, wake_q, wq_sleeper);
+}
+
 void __sched rt_mutex_futex_unlock(struct rt_mutex *lock)
 {
 	DEFINE_WAKE_Q(wake_q);
+	DEFINE_WAKE_Q(wake_sleeper_q);
 	unsigned long flags;
 	bool postunlock;
 
 	raw_spin_lock_irqsave(&lock->wait_lock, flags);
-	postunlock = __rt_mutex_futex_unlock(lock, &wake_q);
+	postunlock = __rt_mutex_futex_unlock(lock, &wake_q, &wake_sleeper_q);
 	raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
 
 	if (postunlock)
-		rt_mutex_postunlock(&wake_q);
+		rt_mutex_postunlock(&wake_q, &wake_sleeper_q);
 }
 
 /**
@ kernel/locking/rtmutex.c:2150 @ void __sched rt_mutex_futex_unlock(struct rt_mutex *lock)
 void rt_mutex_destroy(struct rt_mutex *lock)
 {
 	WARN_ON(rt_mutex_is_locked(lock));
-#ifdef CONFIG_DEBUG_RT_MUTEXES
-	lock->magic = NULL;
-#endif
 }
 EXPORT_SYMBOL_GPL(rt_mutex_destroy);
 
@ kernel/locking/rtmutex.c:2172 @ void __rt_mutex_init(struct rt_mutex *lock, const char *name,
 	if (name && key)
 		debug_rt_mutex_init(lock, name, key);
 }
-EXPORT_SYMBOL_GPL(__rt_mutex_init);
+EXPORT_SYMBOL(__rt_mutex_init);
 
 /**
  * rt_mutex_init_proxy_locked - initialize and lock a rt_mutex on behalf of a
@ kernel/locking/rtmutex.c:2192 @ void rt_mutex_init_proxy_locked(struct rt_mutex *lock,
 				struct task_struct *proxy_owner)
 {
 	__rt_mutex_init(lock, NULL, NULL);
+#ifdef CONFIG_DEBUG_SPINLOCK
+	/*
+	 * get another key class for the wait_lock. LOCK_PI and UNLOCK_PI is
+	 * holding the ->wait_lock of the proxy_lock while unlocking a sleeping
+	 * lock.
+	 */
+	raw_spin_lock_init(&lock->wait_lock);
+#endif
 	debug_rt_mutex_proxy_lock(lock, proxy_owner);
 	rt_mutex_set_owner(lock, proxy_owner);
 }
@ kernel/locking/rtmutex.c:2222 @ void rt_mutex_proxy_unlock(struct rt_mutex *lock)
 	rt_mutex_set_owner(lock, NULL);
 }
 
+static void fixup_rt_mutex_blocked(struct rt_mutex *lock)
+{
+	struct task_struct *tsk = current;
+	/*
+	 * RT has a problem here when the wait got interrupted by a timeout
+	 * or a signal. task->pi_blocked_on is still set. The task must
+	 * acquire the hash bucket lock when returning from this function.
+	 *
+	 * If the hash bucket lock is contended then the
+	 * BUG_ON(rt_mutex_real_waiter(task->pi_blocked_on)) in
+	 * task_blocks_on_rt_mutex() will trigger. This can be avoided by
+	 * clearing task->pi_blocked_on which removes the task from the
+	 * boosting chain of the rtmutex. That's correct because the task
+	 * is not longer blocked on it.
+	 */
+	raw_spin_lock(&tsk->pi_lock);
+	tsk->pi_blocked_on = NULL;
+	raw_spin_unlock(&tsk->pi_lock);
+}
+
 /**
  * __rt_mutex_start_proxy_lock() - Start lock acquisition for another task
  * @lock:		the rt_mutex to take
@ kernel/locking/rtmutex.c:2272 @ int __rt_mutex_start_proxy_lock(struct rt_mutex *lock,
 	if (try_to_take_rt_mutex(lock, task, NULL))
 		return 1;
 
+#ifdef CONFIG_PREEMPT_RT
+	/*
+	 * In PREEMPT_RT there's an added race.
+	 * If the task, that we are about to requeue, times out,
+	 * it can set the PI_WAKEUP_INPROGRESS. This tells the requeue
+	 * to skip this task. But right after the task sets
+	 * its pi_blocked_on to PI_WAKEUP_INPROGRESS it can then
+	 * block on the spin_lock(&hb->lock), which in RT is an rtmutex.
+	 * This will replace the PI_WAKEUP_INPROGRESS with the actual
+	 * lock that it blocks on. We *must not* place this task
+	 * on this proxy lock in that case.
+	 *
+	 * To prevent this race, we first take the task's pi_lock
+	 * and check if it has updated its pi_blocked_on. If it has,
+	 * we assume that it woke up and we return -EAGAIN.
+	 * Otherwise, we set the task's pi_blocked_on to
+	 * PI_REQUEUE_INPROGRESS, so that if the task is waking up
+	 * it will know that we are in the process of requeuing it.
+	 */
+	raw_spin_lock(&task->pi_lock);
+	if (task->pi_blocked_on) {
+		raw_spin_unlock(&task->pi_lock);
+		return -EAGAIN;
+	}
+	task->pi_blocked_on = PI_REQUEUE_INPROGRESS;
+	raw_spin_unlock(&task->pi_lock);
+#endif
+
 	/* We enforce deadlock detection for futexes */
 	ret = task_blocks_on_rt_mutex(lock, waiter, task,
 				      RT_MUTEX_FULL_CHAINWALK);
@ kernel/locking/rtmutex.c:2314 @ int __rt_mutex_start_proxy_lock(struct rt_mutex *lock,
 		ret = 0;
 	}
 
-	debug_rt_mutex_print_deadlock(waiter);
+	if (ret)
+		fixup_rt_mutex_blocked(lock);
 
 	return ret;
 }
@ kernel/locking/rtmutex.c:2400 @ int rt_mutex_wait_proxy_lock(struct rt_mutex *lock,
 	raw_spin_lock_irq(&lock->wait_lock);
 	/* sleep on the mutex */
 	set_current_state(TASK_INTERRUPTIBLE);
-	ret = __rt_mutex_slowlock(lock, TASK_INTERRUPTIBLE, to, waiter);
+	ret = __rt_mutex_slowlock(lock, TASK_INTERRUPTIBLE, to, waiter, NULL);
 	/*
 	 * try_to_take_rt_mutex() sets the waiter bit unconditionally. We might
 	 * have to fix that up.
 	 */
 	fixup_rt_mutex_waiters(lock);
+	if (ret)
+		fixup_rt_mutex_blocked(lock);
+
 	raw_spin_unlock_irq(&lock->wait_lock);
 
 	return ret;
@ kernel/locking/rtmutex.c:2470 @ bool rt_mutex_cleanup_proxy_lock(struct rt_mutex *lock,
 
 	return cleanup;
 }
+
+static inline int
+ww_mutex_deadlock_injection(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
+{
+#ifdef CONFIG_DEBUG_WW_MUTEX_SLOWPATH
+	unsigned int tmp;
+
+	if (ctx->deadlock_inject_countdown-- == 0) {
+		tmp = ctx->deadlock_inject_interval;
+		if (tmp > UINT_MAX/4)
+			tmp = UINT_MAX;
+		else
+			tmp = tmp*2 + tmp + tmp/2;
+
+		ctx->deadlock_inject_interval = tmp;
+		ctx->deadlock_inject_countdown = tmp;
+		ctx->contending_lock = lock;
+
+		ww_mutex_unlock(lock);
+
+		return -EDEADLK;
+	}
+#endif
+
+	return 0;
+}
+
+#ifdef CONFIG_PREEMPT_RT
+int __sched
+ww_mutex_lock_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
+{
+	int ret;
+
+	might_sleep();
+
+	mutex_acquire_nest(&lock->base.dep_map, 0, 0,
+			   ctx ? &ctx->dep_map : NULL, _RET_IP_);
+	ret = rt_mutex_slowlock(&lock->base.lock, TASK_INTERRUPTIBLE, NULL, 0,
+				ctx);
+	if (ret)
+		mutex_release(&lock->base.dep_map, _RET_IP_);
+	else if (!ret && ctx && ctx->acquired > 1)
+		return ww_mutex_deadlock_injection(lock, ctx);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(ww_mutex_lock_interruptible);
+
+int __sched
+ww_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
+{
+	int ret;
+
+	might_sleep();
+
+	mutex_acquire_nest(&lock->base.dep_map, 0, 0,
+			   ctx ? &ctx->dep_map : NULL, _RET_IP_);
+	ret = rt_mutex_slowlock(&lock->base.lock, TASK_UNINTERRUPTIBLE, NULL, 0,
+				ctx);
+	if (ret)
+		mutex_release(&lock->base.dep_map, _RET_IP_);
+	else if (!ret && ctx && ctx->acquired > 1)
+		return ww_mutex_deadlock_injection(lock, ctx);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(ww_mutex_lock);
+
+void __sched ww_mutex_unlock(struct ww_mutex *lock)
+{
+	/*
+	 * The unlocking fastpath is the 0->1 transition from 'locked'
+	 * into 'unlocked' state:
+	 */
+	if (lock->ctx) {
+#ifdef CONFIG_DEBUG_MUTEXES
+		DEBUG_LOCKS_WARN_ON(!lock->ctx->acquired);
+#endif
+		if (lock->ctx->acquired > 0)
+			lock->ctx->acquired--;
+		lock->ctx = NULL;
+	}
+
+	mutex_release(&lock->base.dep_map, _RET_IP_);
+	__rt_mutex_unlock(&lock->base.lock);
+}
+EXPORT_SYMBOL(ww_mutex_unlock);
+
+int __rt_mutex_owner_current(struct rt_mutex *lock)
+{
+	return rt_mutex_owner(lock) == current;
+}
+EXPORT_SYMBOL(__rt_mutex_owner_current);
+#endif
@ kernel/locking/rtmutex.h:22 @
 #define debug_rt_mutex_proxy_unlock(l)			do { } while (0)
 #define debug_rt_mutex_unlock(l)			do { } while (0)
 #define debug_rt_mutex_init(m, n, k)			do { } while (0)
-#define debug_rt_mutex_deadlock(d, a ,l)		do { } while (0)
-#define debug_rt_mutex_print_deadlock(w)		do { } while (0)
 #define debug_rt_mutex_reset_waiter(w)			do { } while (0)
 
-static inline void rt_mutex_print_deadlock(struct rt_mutex_waiter *w)
-{
-	WARN(1, "rtmutex deadlock detected\n");
-}
-
 static inline bool debug_rt_mutex_detect_deadlock(struct rt_mutex_waiter *w,
 						  enum rtmutex_chainwalk walk)
 {
@ kernel/locking/rtmutex_common.h:18 @
 
 #include <linux/rtmutex.h>
 #include <linux/sched/wake_q.h>
+#include <linux/sched/debug.h>
 
 /*
  * This is the control structure for tasks blocked on a rt_mutex,
@ kernel/locking/rtmutex_common.h:33 @ struct rt_mutex_waiter {
 	struct rb_node          pi_tree_entry;
 	struct task_struct	*task;
 	struct rt_mutex		*lock;
-#ifdef CONFIG_DEBUG_RT_MUTEXES
-	unsigned long		ip;
-	struct pid		*deadlock_task_pid;
-	struct rt_mutex		*deadlock_lock;
-#endif
 	int prio;
+	bool			savestate;
 	u64 deadline;
 };
 
@ kernel/locking/rtmutex_common.h:130 @ enum rtmutex_chainwalk {
 /*
  * PI-futex support (proxy locking functions, etc.):
  */
+#define PI_WAKEUP_INPROGRESS	((struct rt_mutex_waiter *) 1)
+#define PI_REQUEUE_INPROGRESS	((struct rt_mutex_waiter *) 2)
+
 extern struct task_struct *rt_mutex_next_owner(struct rt_mutex *lock);
 extern void rt_mutex_init_proxy_locked(struct rt_mutex *lock,
 				       struct task_struct *proxy_owner);
 extern void rt_mutex_proxy_unlock(struct rt_mutex *lock);
-extern void rt_mutex_init_waiter(struct rt_mutex_waiter *waiter);
+extern void rt_mutex_init_waiter(struct rt_mutex_waiter *waiter, bool savetate);
 extern int __rt_mutex_start_proxy_lock(struct rt_mutex *lock,
 				     struct rt_mutex_waiter *waiter,
 				     struct task_struct *task);
@ kernel/locking/rtmutex_common.h:155 @ extern int __rt_mutex_futex_trylock(struct rt_mutex *l);
 
 extern void rt_mutex_futex_unlock(struct rt_mutex *lock);
 extern bool __rt_mutex_futex_unlock(struct rt_mutex *lock,
-				 struct wake_q_head *wqh);
-
-extern void rt_mutex_postunlock(struct wake_q_head *wake_q);
+				 struct wake_q_head *wqh,
+				 struct wake_q_head *wq_sleeper);
+
+extern void rt_mutex_postunlock(struct wake_q_head *wake_q,
+				struct wake_q_head *wake_sleeper_q);
+
+/* RW semaphore special interface */
+struct ww_acquire_ctx;
+
+extern int __rt_mutex_lock_state(struct rt_mutex *lock, int state);
+extern int __rt_mutex_trylock(struct rt_mutex *lock);
+extern void __rt_mutex_unlock(struct rt_mutex *lock);
+int __sched rt_mutex_slowlock_locked(struct rt_mutex *lock, int state,
+				     struct hrtimer_sleeper *timeout,
+				     enum rtmutex_chainwalk chwalk,
+				     struct ww_acquire_ctx *ww_ctx,
+				     struct rt_mutex_waiter *waiter);
+void __sched rt_spin_lock_slowlock_locked(struct rt_mutex *lock,
+					  struct rt_mutex_waiter *waiter,
+					  unsigned long flags);
+void __sched rt_spin_lock_slowunlock(struct rt_mutex *lock);
 
 #ifdef CONFIG_DEBUG_RT_MUTEXES
 # include "rtmutex-debug.h"
@ kernel/locking/rwlock-rt.c:4 @
+// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/sched/debug.h>
+#include <linux/export.h>
+
+#include "rtmutex_common.h"
+#include <linux/rwlock_types_rt.h>
+
+/*
+ * RT-specific reader/writer locks
+ *
+ * write_lock()
+ *  1) Lock lock->rtmutex
+ *  2) Remove the reader BIAS to force readers into the slow path
+ *  3) Wait until all readers have left the critical region
+ *  4) Mark it write locked
+ *
+ * write_unlock()
+ *  1) Remove the write locked marker
+ *  2) Set the reader BIAS so readers can use the fast path again
+ *  3) Unlock lock->rtmutex to release blocked readers
+ *
+ * read_lock()
+ *  1) Try fast path acquisition (reader BIAS is set)
+ *  2) Take lock->rtmutex.wait_lock which protects the writelocked flag
+ *  3) If !writelocked, acquire it for read
+ *  4) If writelocked, block on lock->rtmutex
+ *  5) unlock lock->rtmutex, goto 1)
+ *
+ * read_unlock()
+ *  1) Try fast path release (reader count != 1)
+ *  2) Wake the writer waiting in write_lock()#3
+ *
+ * read_lock()#3 has the consequence, that rw locks on RT are not writer
+ * fair, but writers, which should be avoided in RT tasks (think tasklist
+ * lock), are subject to the rtmutex priority/DL inheritance mechanism.
+ *
+ * It's possible to make the rw locks writer fair by keeping a list of
+ * active readers. A blocked writer would force all newly incoming readers
+ * to block on the rtmutex, but the rtmutex would have to be proxy locked
+ * for one reader after the other. We can't use multi-reader inheritance
+ * because there is no way to support that with
+ * SCHED_DEADLINE. Implementing the one by one reader boosting/handover
+ * mechanism is a major surgery for a very dubious value.
+ *
+ * The risk of writer starvation is there, but the pathological use cases
+ * which trigger it are not necessarily the typical RT workloads.
+ */
+
+void __rwlock_biased_rt_init(struct rt_rw_lock *lock, const char *name,
+			     struct lock_class_key *key)
+{
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+	/*
+	 * Make sure we are not reinitializing a held semaphore:
+	 */
+	debug_check_no_locks_freed((void *)lock, sizeof(*lock));
+	lockdep_init_map(&lock->dep_map, name, key, 0);
+#endif
+	atomic_set(&lock->readers, READER_BIAS);
+	rt_mutex_init(&lock->rtmutex);
+	lock->rtmutex.save_state = 1;
+}
+
+static int __read_rt_trylock(struct rt_rw_lock *lock)
+{
+	int r, old;
+
+	/*
+	 * Increment reader count, if lock->readers < 0, i.e. READER_BIAS is
+	 * set.
+	 */
+	for (r = atomic_read(&lock->readers); r < 0;) {
+		old = atomic_cmpxchg(&lock->readers, r, r + 1);
+		if (likely(old == r))
+			return 1;
+		r = old;
+	}
+	return 0;
+}
+
+static void __read_rt_lock(struct rt_rw_lock *lock)
+{
+	struct rt_mutex *m = &lock->rtmutex;
+	struct rt_mutex_waiter waiter;
+	unsigned long flags;
+
+	if (__read_rt_trylock(lock))
+		return;
+
+	raw_spin_lock_irqsave(&m->wait_lock, flags);
+	/*
+	 * Allow readers as long as the writer has not completely
+	 * acquired the semaphore for write.
+	 */
+	if (atomic_read(&lock->readers) != WRITER_BIAS) {
+		atomic_inc(&lock->readers);
+		raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+		return;
+	}
+
+	/*
+	 * Call into the slow lock path with the rtmutex->wait_lock
+	 * held, so this can't result in the following race:
+	 *
+	 * Reader1		Reader2		Writer
+	 *			read_lock()
+	 *					write_lock()
+	 *					rtmutex_lock(m)
+	 *					swait()
+	 * read_lock()
+	 * unlock(m->wait_lock)
+	 *			read_unlock()
+	 *			swake()
+	 *					lock(m->wait_lock)
+	 *					lock->writelocked=true
+	 *					unlock(m->wait_lock)
+	 *
+	 *					write_unlock()
+	 *					lock->writelocked=false
+	 *					rtmutex_unlock(m)
+	 *			read_lock()
+	 *					write_lock()
+	 *					rtmutex_lock(m)
+	 *					swait()
+	 * rtmutex_lock(m)
+	 *
+	 * That would put Reader1 behind the writer waiting on
+	 * Reader2 to call read_unlock() which might be unbound.
+	 */
+	rt_mutex_init_waiter(&waiter, true);
+	rt_spin_lock_slowlock_locked(m, &waiter, flags);
+	/*
+	 * The slowlock() above is guaranteed to return with the rtmutex is
+	 * now held, so there can't be a writer active. Increment the reader
+	 * count and immediately drop the rtmutex again.
+	 */
+	atomic_inc(&lock->readers);
+	raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+	rt_spin_lock_slowunlock(m);
+
+	debug_rt_mutex_free_waiter(&waiter);
+}
+
+static void __read_rt_unlock(struct rt_rw_lock *lock)
+{
+	struct rt_mutex *m = &lock->rtmutex;
+	struct task_struct *tsk;
+
+	/*
+	 * sem->readers can only hit 0 when a writer is waiting for the
+	 * active readers to leave the critical region.
+	 */
+	if (!atomic_dec_and_test(&lock->readers))
+		return;
+
+	raw_spin_lock_irq(&m->wait_lock);
+	/*
+	 * Wake the writer, i.e. the rtmutex owner. It might release the
+	 * rtmutex concurrently in the fast path, but to clean up the rw
+	 * lock it needs to acquire m->wait_lock. The worst case which can
+	 * happen is a spurious wakeup.
+	 */
+	tsk = rt_mutex_owner(m);
+	if (tsk)
+		wake_up_process(tsk);
+
+	raw_spin_unlock_irq(&m->wait_lock);
+}
+
+static void __write_unlock_common(struct rt_rw_lock *lock, int bias,
+				  unsigned long flags)
+{
+	struct rt_mutex *m = &lock->rtmutex;
+
+	atomic_add(READER_BIAS - bias, &lock->readers);
+	raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+	rt_spin_lock_slowunlock(m);
+}
+
+static void __write_rt_lock(struct rt_rw_lock *lock)
+{
+	struct rt_mutex *m = &lock->rtmutex;
+	struct task_struct *self = current;
+	unsigned long flags;
+
+	/* Take the rtmutex as a first step */
+	__rt_spin_lock(m);
+
+	/* Force readers into slow path */
+	atomic_sub(READER_BIAS, &lock->readers);
+
+	raw_spin_lock_irqsave(&m->wait_lock, flags);
+
+	raw_spin_lock(&self->pi_lock);
+	self->saved_state = self->state;
+	__set_current_state_no_track(TASK_UNINTERRUPTIBLE);
+	raw_spin_unlock(&self->pi_lock);
+
+	for (;;) {
+		/* Have all readers left the critical region? */
+		if (!atomic_read(&lock->readers)) {
+			atomic_set(&lock->readers, WRITER_BIAS);
+			raw_spin_lock(&self->pi_lock);
+			__set_current_state_no_track(self->saved_state);
+			self->saved_state = TASK_RUNNING;
+			raw_spin_unlock(&self->pi_lock);
+			raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+			return;
+		}
+
+		raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+
+		if (atomic_read(&lock->readers) != 0)
+			preempt_schedule_lock();
+
+		raw_spin_lock_irqsave(&m->wait_lock, flags);
+
+		raw_spin_lock(&self->pi_lock);
+		__set_current_state_no_track(TASK_UNINTERRUPTIBLE);
+		raw_spin_unlock(&self->pi_lock);
+	}
+}
+
+static int __write_rt_trylock(struct rt_rw_lock *lock)
+{
+	struct rt_mutex *m = &lock->rtmutex;
+	unsigned long flags;
+
+	if (!__rt_mutex_trylock(m))
+		return 0;
+
+	atomic_sub(READER_BIAS, &lock->readers);
+
+	raw_spin_lock_irqsave(&m->wait_lock, flags);
+	if (!atomic_read(&lock->readers)) {
+		atomic_set(&lock->readers, WRITER_BIAS);
+		raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+		return 1;
+	}
+	__write_unlock_common(lock, 0, flags);
+	return 0;
+}
+
+static void __write_rt_unlock(struct rt_rw_lock *lock)
+{
+	struct rt_mutex *m = &lock->rtmutex;
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&m->wait_lock, flags);
+	__write_unlock_common(lock, WRITER_BIAS, flags);
+}
+
+int __lockfunc rt_read_can_lock(rwlock_t *rwlock)
+{
+	return  atomic_read(&rwlock->readers) < 0;
+}
+
+int __lockfunc rt_write_can_lock(rwlock_t *rwlock)
+{
+	return atomic_read(&rwlock->readers) == READER_BIAS;
+}
+
+/*
+ * The common functions which get wrapped into the rwlock API.
+ */
+int __lockfunc rt_read_trylock(rwlock_t *rwlock)
+{
+	int ret;
+
+	ret = __read_rt_trylock(rwlock);
+	if (ret) {
+		rwlock_acquire_read(&rwlock->dep_map, 0, 1, _RET_IP_);
+		rcu_read_lock();
+		migrate_disable();
+	}
+	return ret;
+}
+EXPORT_SYMBOL(rt_read_trylock);
+
+int __lockfunc rt_write_trylock(rwlock_t *rwlock)
+{
+	int ret;
+
+	ret = __write_rt_trylock(rwlock);
+	if (ret) {
+		rwlock_acquire(&rwlock->dep_map, 0, 1, _RET_IP_);
+		rcu_read_lock();
+		migrate_disable();
+	}
+	return ret;
+}
+EXPORT_SYMBOL(rt_write_trylock);
+
+void __lockfunc rt_read_lock(rwlock_t *rwlock)
+{
+	rwlock_acquire_read(&rwlock->dep_map, 0, 0, _RET_IP_);
+	__read_rt_lock(rwlock);
+	rcu_read_lock();
+	migrate_disable();
+}
+EXPORT_SYMBOL(rt_read_lock);
+
+void __lockfunc rt_write_lock(rwlock_t *rwlock)
+{
+	rwlock_acquire(&rwlock->dep_map, 0, 0, _RET_IP_);
+	__write_rt_lock(rwlock);
+	rcu_read_lock();
+	migrate_disable();
+}
+EXPORT_SYMBOL(rt_write_lock);
+
+void __lockfunc rt_read_unlock(rwlock_t *rwlock)
+{
+	rwlock_release(&rwlock->dep_map, _RET_IP_);
+	migrate_enable();
+	rcu_read_unlock();
+	__read_rt_unlock(rwlock);
+}
+EXPORT_SYMBOL(rt_read_unlock);
+
+void __lockfunc rt_write_unlock(rwlock_t *rwlock)
+{
+	rwlock_release(&rwlock->dep_map, _RET_IP_);
+	migrate_enable();
+	rcu_read_unlock();
+	__write_rt_unlock(rwlock);
+}
+EXPORT_SYMBOL(rt_write_unlock);
+
+void __rt_rwlock_init(rwlock_t *rwlock, char *name, struct lock_class_key *key)
+{
+	__rwlock_biased_rt_init(rwlock, name, key);
+}
+EXPORT_SYMBOL(__rt_rwlock_init);
@ kernel/locking/rwsem-rt.c:4 @
+// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/rwsem.h>
+#include <linux/sched/debug.h>
+#include <linux/sched/signal.h>
+#include <linux/export.h>
+#include <linux/blkdev.h>
+
+#include "rtmutex_common.h"
+
+/*
+ * RT-specific reader/writer semaphores
+ *
+ * down_write()
+ *  1) Lock sem->rtmutex
+ *  2) Remove the reader BIAS to force readers into the slow path
+ *  3) Wait until all readers have left the critical region
+ *  4) Mark it write locked
+ *
+ * up_write()
+ *  1) Remove the write locked marker
+ *  2) Set the reader BIAS so readers can use the fast path again
+ *  3) Unlock sem->rtmutex to release blocked readers
+ *
+ * down_read()
+ *  1) Try fast path acquisition (reader BIAS is set)
+ *  2) Take sem->rtmutex.wait_lock which protects the writelocked flag
+ *  3) If !writelocked, acquire it for read
+ *  4) If writelocked, block on sem->rtmutex
+ *  5) unlock sem->rtmutex, goto 1)
+ *
+ * up_read()
+ *  1) Try fast path release (reader count != 1)
+ *  2) Wake the writer waiting in down_write()#3
+ *
+ * down_read()#3 has the consequence, that rw semaphores on RT are not writer
+ * fair, but writers, which should be avoided in RT tasks (think mmap_sem),
+ * are subject to the rtmutex priority/DL inheritance mechanism.
+ *
+ * It's possible to make the rw semaphores writer fair by keeping a list of
+ * active readers. A blocked writer would force all newly incoming readers to
+ * block on the rtmutex, but the rtmutex would have to be proxy locked for one
+ * reader after the other. We can't use multi-reader inheritance because there
+ * is no way to support that with SCHED_DEADLINE. Implementing the one by one
+ * reader boosting/handover mechanism is a major surgery for a very dubious
+ * value.
+ *
+ * The risk of writer starvation is there, but the pathological use cases
+ * which trigger it are not necessarily the typical RT workloads.
+ */
+
+void __rwsem_init(struct rw_semaphore *sem, const char *name,
+		  struct lock_class_key *key)
+{
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+	/*
+	 * Make sure we are not reinitializing a held semaphore:
+	 */
+	debug_check_no_locks_freed((void *)sem, sizeof(*sem));
+	lockdep_init_map(&sem->dep_map, name, key, 0);
+#endif
+	atomic_set(&sem->readers, READER_BIAS);
+}
+EXPORT_SYMBOL(__rwsem_init);
+
+int __down_read_trylock(struct rw_semaphore *sem)
+{
+	int r, old;
+
+	/*
+	 * Increment reader count, if sem->readers < 0, i.e. READER_BIAS is
+	 * set.
+	 */
+	for (r = atomic_read(&sem->readers); r < 0;) {
+		old = atomic_cmpxchg(&sem->readers, r, r + 1);
+		if (likely(old == r))
+			return 1;
+		r = old;
+	}
+	return 0;
+}
+
+static int __sched __down_read_common(struct rw_semaphore *sem, int state)
+{
+	struct rt_mutex *m = &sem->rtmutex;
+	struct rt_mutex_waiter waiter;
+	int ret;
+
+	if (__down_read_trylock(sem))
+		return 0;
+
+	/*
+	 * Flush blk before ->pi_blocked_on is set. At schedule() time it is too
+	 * late if one of the callbacks needs to acquire a sleeping lock.
+	 */
+	if (blk_needs_flush_plug(current))
+		blk_schedule_flush_plug(current);
+
+	might_sleep();
+	raw_spin_lock_irq(&m->wait_lock);
+	/*
+	 * Allow readers as long as the writer has not completely
+	 * acquired the semaphore for write.
+	 */
+	if (atomic_read(&sem->readers) != WRITER_BIAS) {
+		atomic_inc(&sem->readers);
+		raw_spin_unlock_irq(&m->wait_lock);
+		return 0;
+	}
+
+	/*
+	 * Call into the slow lock path with the rtmutex->wait_lock
+	 * held, so this can't result in the following race:
+	 *
+	 * Reader1		Reader2		Writer
+	 *			down_read()
+	 *					down_write()
+	 *					rtmutex_lock(m)
+	 *					swait()
+	 * down_read()
+	 * unlock(m->wait_lock)
+	 *			up_read()
+	 *			swake()
+	 *					lock(m->wait_lock)
+	 *					sem->writelocked=true
+	 *					unlock(m->wait_lock)
+	 *
+	 *					up_write()
+	 *					sem->writelocked=false
+	 *					rtmutex_unlock(m)
+	 *			down_read()
+	 *					down_write()
+	 *					rtmutex_lock(m)
+	 *					swait()
+	 * rtmutex_lock(m)
+	 *
+	 * That would put Reader1 behind the writer waiting on
+	 * Reader2 to call up_read() which might be unbound.
+	 */
+	rt_mutex_init_waiter(&waiter, false);
+	ret = rt_mutex_slowlock_locked(m, state, NULL, RT_MUTEX_MIN_CHAINWALK,
+				       NULL, &waiter);
+	/*
+	 * The slowlock() above is guaranteed to return with the rtmutex (for
+	 * ret = 0) is now held, so there can't be a writer active. Increment
+	 * the reader count and immediately drop the rtmutex again.
+	 * For ret != 0 we don't hold the rtmutex and need unlock the wait_lock.
+	 * We don't own the lock then.
+	 */
+	if (!ret)
+		atomic_inc(&sem->readers);
+	raw_spin_unlock_irq(&m->wait_lock);
+	if (!ret)
+		__rt_mutex_unlock(m);
+
+	debug_rt_mutex_free_waiter(&waiter);
+	return ret;
+}
+
+void __down_read(struct rw_semaphore *sem)
+{
+	int ret;
+
+	ret = __down_read_common(sem, TASK_UNINTERRUPTIBLE);
+	WARN_ON_ONCE(ret);
+}
+
+int __down_read_interruptible(struct rw_semaphore *sem)
+{
+	int ret;
+
+	ret = __down_read_common(sem, TASK_INTERRUPTIBLE);
+	if (likely(!ret))
+		return ret;
+	WARN_ONCE(ret != -EINTR, "Unexpected state: %d\n", ret);
+	return -EINTR;
+}
+
+int __down_read_killable(struct rw_semaphore *sem)
+{
+	int ret;
+
+	ret = __down_read_common(sem, TASK_KILLABLE);
+	if (likely(!ret))
+		return ret;
+	WARN_ONCE(ret != -EINTR, "Unexpected state: %d\n", ret);
+	return -EINTR;
+}
+
+void __up_read(struct rw_semaphore *sem)
+{
+	struct rt_mutex *m = &sem->rtmutex;
+	struct task_struct *tsk;
+
+	/*
+	 * sem->readers can only hit 0 when a writer is waiting for the
+	 * active readers to leave the critical region.
+	 */
+	if (!atomic_dec_and_test(&sem->readers))
+		return;
+
+	raw_spin_lock_irq(&m->wait_lock);
+	/*
+	 * Wake the writer, i.e. the rtmutex owner. It might release the
+	 * rtmutex concurrently in the fast path (due to a signal), but to
+	 * clean up the rwsem it needs to acquire m->wait_lock. The worst
+	 * case which can happen is a spurious wakeup.
+	 */
+	tsk = rt_mutex_owner(m);
+	if (tsk)
+		wake_up_process(tsk);
+
+	raw_spin_unlock_irq(&m->wait_lock);
+}
+
+static void __up_write_unlock(struct rw_semaphore *sem, int bias,
+			      unsigned long flags)
+{
+	struct rt_mutex *m = &sem->rtmutex;
+
+	atomic_add(READER_BIAS - bias, &sem->readers);
+	raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+	__rt_mutex_unlock(m);
+}
+
+static int __sched __down_write_common(struct rw_semaphore *sem, int state)
+{
+	struct rt_mutex *m = &sem->rtmutex;
+	unsigned long flags;
+
+	/*
+	 * Flush blk before ->pi_blocked_on is set. At schedule() time it is too
+	 * late if one of the callbacks needs to acquire a sleeping lock.
+	 */
+	if (blk_needs_flush_plug(current))
+		blk_schedule_flush_plug(current);
+
+	/* Take the rtmutex as a first step */
+	if (__rt_mutex_lock_state(m, state))
+		return -EINTR;
+
+	/* Force readers into slow path */
+	atomic_sub(READER_BIAS, &sem->readers);
+	might_sleep();
+
+	set_current_state(state);
+	for (;;) {
+		raw_spin_lock_irqsave(&m->wait_lock, flags);
+		/* Have all readers left the critical region? */
+		if (!atomic_read(&sem->readers)) {
+			atomic_set(&sem->readers, WRITER_BIAS);
+			__set_current_state(TASK_RUNNING);
+			raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+			return 0;
+		}
+
+		if (signal_pending_state(state, current)) {
+			__set_current_state(TASK_RUNNING);
+			__up_write_unlock(sem, 0, flags);
+			return -EINTR;
+		}
+		raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+
+		if (atomic_read(&sem->readers) != 0) {
+			schedule();
+			set_current_state(state);
+		}
+	}
+}
+
+void __sched __down_write(struct rw_semaphore *sem)
+{
+	__down_write_common(sem, TASK_UNINTERRUPTIBLE);
+}
+
+int __sched __down_write_killable(struct rw_semaphore *sem)
+{
+	return __down_write_common(sem, TASK_KILLABLE);
+}
+
+int __down_write_trylock(struct rw_semaphore *sem)
+{
+	struct rt_mutex *m = &sem->rtmutex;
+	unsigned long flags;
+
+	if (!__rt_mutex_trylock(m))
+		return 0;
+
+	atomic_sub(READER_BIAS, &sem->readers);
+
+	raw_spin_lock_irqsave(&m->wait_lock, flags);
+	if (!atomic_read(&sem->readers)) {
+		atomic_set(&sem->readers, WRITER_BIAS);
+		raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+		return 1;
+	}
+	__up_write_unlock(sem, 0, flags);
+	return 0;
+}
+
+void __up_write(struct rw_semaphore *sem)
+{
+	struct rt_mutex *m = &sem->rtmutex;
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&m->wait_lock, flags);
+	__up_write_unlock(sem, WRITER_BIAS, flags);
+}
+
+void __downgrade_write(struct rw_semaphore *sem)
+{
+	struct rt_mutex *m = &sem->rtmutex;
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&m->wait_lock, flags);
+	/* Release it and account current as reader */
+	__up_write_unlock(sem, WRITER_BIAS - 1, flags);
+}
@ kernel/locking/rwsem.c:31 @
 #include <linux/rwsem.h>
 #include <linux/atomic.h>
 
+#ifndef CONFIG_PREEMPT_RT
 #include "lock_events.h"
 
 /*
@ kernel/locking/rwsem.c:1498 @ static inline void __downgrade_write(struct rw_semaphore *sem)
 	if (tmp & RWSEM_FLAG_WAITERS)
 		rwsem_downgrade_wake(sem);
 }
+#endif
 
 /*
  * lock for reading
@ kernel/locking/rwsem.c:1662 @ void down_read_non_owner(struct rw_semaphore *sem)
 {
 	might_sleep();
 	__down_read(sem);
+#ifndef CONFIG_PREEMPT_RT
 	__rwsem_set_reader_owned(sem, NULL);
+#endif
 }
 EXPORT_SYMBOL(down_read_non_owner);
 
@ kernel/locking/rwsem.c:1693 @ EXPORT_SYMBOL(down_write_killable_nested);
 
 void up_read_non_owner(struct rw_semaphore *sem)
 {
+#ifndef CONFIG_PREEMPT_RT
 	DEBUG_RWSEMS_WARN_ON(!is_rwsem_reader_owned(sem), sem);
+#endif
 	__up_read(sem);
 }
 EXPORT_SYMBOL(up_read_non_owner);
@ kernel/locking/spinlock.c:127 @ void __lockfunc __raw_##op##_lock_bh(locktype##_t *lock)		\
  *         __[spin|read|write]_lock_bh()
  */
 BUILD_LOCK_OPS(spin, raw_spinlock);
+
+#ifndef CONFIG_PREEMPT_RT
 BUILD_LOCK_OPS(read, rwlock);
 BUILD_LOCK_OPS(write, rwlock);
+#endif
 
 #endif
 
@ kernel/locking/spinlock.c:215 @ void __lockfunc _raw_spin_unlock_bh(raw_spinlock_t *lock)
 EXPORT_SYMBOL(_raw_spin_unlock_bh);
 #endif
 
+#ifndef CONFIG_PREEMPT_RT
+
 #ifndef CONFIG_INLINE_READ_TRYLOCK
 int __lockfunc _raw_read_trylock(rwlock_t *lock)
 {
@ kernel/locking/spinlock.c:361 @ void __lockfunc _raw_write_unlock_bh(rwlock_t *lock)
 EXPORT_SYMBOL(_raw_write_unlock_bh);
 #endif
 
+#endif /* !PREEMPT_RT */
+
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 
 void __lockfunc _raw_spin_lock_nested(raw_spinlock_t *lock, int subclass)
@ kernel/locking/spinlock_debug.c:34 @ void __raw_spin_lock_init(raw_spinlock_t *lock, const char *name,
 
 EXPORT_SYMBOL(__raw_spin_lock_init);
 
+#ifndef CONFIG_PREEMPT_RT
 void __rwlock_init(rwlock_t *lock, const char *name,
 		   struct lock_class_key *key)
 {
@ kernel/locking/spinlock_debug.c:52 @ void __rwlock_init(rwlock_t *lock, const char *name,
 }
 
 EXPORT_SYMBOL(__rwlock_init);
+#endif
 
 static void spin_dump(raw_spinlock_t *lock, const char *msg)
 {
@ kernel/locking/spinlock_debug.c:144 @ void do_raw_spin_unlock(raw_spinlock_t *lock)
 	arch_spin_unlock(&lock->raw_lock);
 }
 
+#ifndef CONFIG_PREEMPT_RT
 static void rwlock_bug(rwlock_t *lock, const char *msg)
 {
 	if (!debug_locks_off())
@ kernel/locking/spinlock_debug.c:234 @ void do_raw_write_unlock(rwlock_t *lock)
 	debug_write_unlock(lock);
 	arch_write_unlock(&lock->raw_lock);
 }
+
+#endif
@ kernel/notifier.c:145 @ int atomic_notifier_chain_register(struct atomic_notifier_head *nh,
 	unsigned long flags;
 	int ret;
 
-	spin_lock_irqsave(&nh->lock, flags);
+	raw_spin_lock_irqsave(&nh->lock, flags);
 	ret = notifier_chain_register(&nh->head, n);
-	spin_unlock_irqrestore(&nh->lock, flags);
+	raw_spin_unlock_irqrestore(&nh->lock, flags);
 	return ret;
 }
 EXPORT_SYMBOL_GPL(atomic_notifier_chain_register);
@ kernel/notifier.c:167 @ int atomic_notifier_chain_unregister(struct atomic_notifier_head *nh,
 	unsigned long flags;
 	int ret;
 
-	spin_lock_irqsave(&nh->lock, flags);
+	raw_spin_lock_irqsave(&nh->lock, flags);
 	ret = notifier_chain_unregister(&nh->head, n);
-	spin_unlock_irqrestore(&nh->lock, flags);
+	raw_spin_unlock_irqrestore(&nh->lock, flags);
 	synchronize_rcu();
 	return ret;
 }
@ kernel/notifier.c:185 @ int atomic_notifier_call_chain_robust(struct atomic_notifier_head *nh,
 	 * Musn't use RCU; because then the notifier list can
 	 * change between the up and down traversal.
 	 */
-	spin_lock_irqsave(&nh->lock, flags);
+	raw_spin_lock_irqsave(&nh->lock, flags);
 	ret = notifier_call_chain_robust(&nh->head, val_up, val_down, v);
-	spin_unlock_irqrestore(&nh->lock, flags);
+	raw_spin_unlock_irqrestore(&nh->lock, flags);
 
 	return ret;
 }
@ kernel/panic.c:180 @ static void panic_print_sys_info(void)
 void panic(const char *fmt, ...)
 {
 	static char buf[1024];
+	va_list args2;
 	va_list args;
 	long i, i_next = 0, len;
 	int state = 0;
 	int old_cpu, this_cpu;
 	bool _crash_kexec_post_notifiers = crash_kexec_post_notifiers;
 
+	console_verbose();
+	pr_emerg("Kernel panic - not syncing:\n");
+	va_start(args2, fmt);
+	va_copy(args, args2);
+	vprintk(fmt, args2);
+	va_end(args2);
+#ifdef CONFIG_DEBUG_BUGVERBOSE
+	/*
+	 * Avoid nested stack-dumping if a panic occurs during oops processing
+	 */
+	if (!test_taint(TAINT_DIE) && oops_in_progress <= 1)
+		dump_stack();
+#endif
+	pr_flush(1000, true);
+
 	/*
 	 * Disable local interrupts. This will prevent panic_smp_self_stop
 	 * from deadlocking the first cpu that invokes the panic, since
@ kernel/panic.c:232 @ void panic(const char *fmt, ...)
 	if (old_cpu != PANIC_CPU_INVALID && old_cpu != this_cpu)
 		panic_smp_self_stop();
 
-	console_verbose();
 	bust_spinlocks(1);
-	va_start(args, fmt);
 	len = vscnprintf(buf, sizeof(buf), fmt, args);
 	va_end(args);
 
 	if (len && buf[len - 1] == '\n')
 		buf[len - 1] = '\0';
 
-	pr_emerg("Kernel panic - not syncing: %s\n", buf);
-#ifdef CONFIG_DEBUG_BUGVERBOSE
-	/*
-	 * Avoid nested stack-dumping if a panic occurs during oops processing
-	 */
-	if (!test_taint(TAINT_DIE) && oops_in_progress <= 1)
-		dump_stack();
-#endif
-
 	/*
 	 * If kgdb is enabled, give it a chance to run before we stop all
 	 * the other CPUs or else we won't be able to debug processes left
@ kernel/panic.c:255 @ void panic(const char *fmt, ...)
 	 * Bypass the panic_cpu check and call __crash_kexec directly.
 	 */
 	if (!_crash_kexec_post_notifiers) {
-		printk_safe_flush_on_panic();
 		__crash_kexec(NULL);
 
 		/*
@ kernel/panic.c:278 @ void panic(const char *fmt, ...)
 	 */
 	atomic_notifier_call_chain(&panic_notifier_list, 0, buf);
 
-	/* Call flush even twice. It tries harder with a single online CPU */
-	printk_safe_flush_on_panic();
 	kmsg_dump(KMSG_DUMP_PANIC);
 
 	/*
@ kernel/panic.c:547 @ static u64 oops_id;
 
 static int init_oops_id(void)
 {
+#ifndef CONFIG_PREEMPT_RT
 	if (!oops_id)
 		get_random_bytes(&oops_id, sizeof(oops_id));
 	else
+#endif
 		oops_id++;
 
 	return 0;
@ kernel/panic.c:562 @ static void print_oops_end_marker(void)
 {
 	init_oops_id();
 	pr_warn("---[ end trace %016llx ]---\n", (unsigned long long)oops_id);
+	pr_flush(1000, true);
 }
 
 /*
@ kernel/printk/Makefile:1 @
 # SPDX-License-Identifier: GPL-2.0-only
 obj-y	= printk.o
-obj-$(CONFIG_PRINTK)	+= printk_safe.o
 obj-$(CONFIG_A11Y_BRAILLE_CONSOLE)	+= braille.o
 obj-$(CONFIG_PRINTK)	+= printk_ringbuffer.o
@ kernel/printk/internal.h:1 @
-/* SPDX-License-Identifier: GPL-2.0-or-later */
-/*
- * internal.h - printk internal definitions
- */
-#include <linux/percpu.h>
-
-#ifdef CONFIG_PRINTK
-
-#define PRINTK_SAFE_CONTEXT_MASK	0x007ffffff
-#define PRINTK_NMI_DIRECT_CONTEXT_MASK	0x008000000
-#define PRINTK_NMI_CONTEXT_MASK		0xff0000000
-
-#define PRINTK_NMI_CONTEXT_OFFSET	0x010000000
-
-extern raw_spinlock_t logbuf_lock;
-
-__printf(4, 0)
-int vprintk_store(int facility, int level,
-		  const struct dev_printk_info *dev_info,
-		  const char *fmt, va_list args);
-
-__printf(1, 0) int vprintk_default(const char *fmt, va_list args);
-__printf(1, 0) int vprintk_deferred(const char *fmt, va_list args);
-__printf(1, 0) int vprintk_func(const char *fmt, va_list args);
-void __printk_safe_enter(void);
-void __printk_safe_exit(void);
-
-void printk_safe_init(void);
-bool printk_percpu_data_ready(void);
-
-#define printk_safe_enter_irqsave(flags)	\
-	do {					\
-		local_irq_save(flags);		\
-		__printk_safe_enter();		\
-	} while (0)
-
-#define printk_safe_exit_irqrestore(flags)	\
-	do {					\
-		__printk_safe_exit();		\
-		local_irq_restore(flags);	\
-	} while (0)
-
-#define printk_safe_enter_irq()		\
-	do {					\
-		local_irq_disable();		\
-		__printk_safe_enter();		\
-	} while (0)
-
-#define printk_safe_exit_irq()			\
-	do {					\
-		__printk_safe_exit();		\
-		local_irq_enable();		\
-	} while (0)
-
-void defer_console_output(void);
-
-#else
-
-__printf(1, 0) int vprintk_func(const char *fmt, va_list args) { return 0; }
-
-/*
- * In !PRINTK builds we still export logbuf_lock spin_lock, console_sem
- * semaphore and some of console functions (console_unlock()/etc.), so
- * printk-safe must preserve the existing local IRQ guarantees.
- */
-#define printk_safe_enter_irqsave(flags) local_irq_save(flags)
-#define printk_safe_exit_irqrestore(flags) local_irq_restore(flags)
-
-#define printk_safe_enter_irq() local_irq_disable()
-#define printk_safe_exit_irq() local_irq_enable()
-
-static inline void printk_safe_init(void) { }
-static inline bool printk_percpu_data_ready(void) { return false; }
-#endif /* CONFIG_PRINTK */
@ kernel/printk/printk.c:47 @
 #include <linux/irq_work.h>
 #include <linux/ctype.h>
 #include <linux/uio.h>
+#include <linux/kthread.h>
+#include <linux/kdb.h>
+#include <linux/clocksource.h>
 #include <linux/sched/clock.h>
 #include <linux/sched/debug.h>
 #include <linux/sched/task_stack.h>
@ kernel/printk/printk.c:64 @
 #include "printk_ringbuffer.h"
 #include "console_cmdline.h"
 #include "braille.h"
-#include "internal.h"
 
 int console_printk[4] = {
 	CONSOLE_LOGLEVEL_DEFAULT,	/* console_loglevel */
@ kernel/printk/printk.c:230 @ static int nr_ext_console_drivers;
 
 static int __down_trylock_console_sem(unsigned long ip)
 {
-	int lock_failed;
-	unsigned long flags;
-
-	/*
-	 * Here and in __up_console_sem() we need to be in safe mode,
-	 * because spindump/WARN/etc from under console ->lock will
-	 * deadlock in printk()->down_trylock_console_sem() otherwise.
-	 */
-	printk_safe_enter_irqsave(flags);
-	lock_failed = down_trylock(&console_sem);
-	printk_safe_exit_irqrestore(flags);
-
-	if (lock_failed)
+	if (down_trylock(&console_sem))
 		return 1;
 	mutex_acquire(&console_lock_dep_map, 0, 1, ip);
 	return 0;
@ kernel/printk/printk.c:239 @ static int __down_trylock_console_sem(unsigned long ip)
 
 static void __up_console_sem(unsigned long ip)
 {
-	unsigned long flags;
-
 	mutex_release(&console_lock_dep_map, ip);
 
-	printk_safe_enter_irqsave(flags);
 	up(&console_sem);
-	printk_safe_exit_irqrestore(flags);
 }
 #define up_console_sem() __up_console_sem(_RET_IP_)
 
@ kernel/printk/printk.c:255 @ static void __up_console_sem(unsigned long ip)
  */
 static int console_locked, console_suspended;
 
-/*
- * If exclusive_console is non-NULL then only this console is to be printed to.
- */
-static struct console *exclusive_console;
-
 /*
  *	Array of consoles built from command line options (console=)
  */
@ kernel/printk/printk.c:339 @ enum log_flags {
 	LOG_CONT	= 8,	/* text is a fragment of a continuation line */
 };
 
-/*
- * The logbuf_lock protects kmsg buffer, indices, counters.  This can be taken
- * within the scheduler's rq lock. It must be released before calling
- * console_unlock() or anything else that might wake up a process.
- */
-DEFINE_RAW_SPINLOCK(logbuf_lock);
+#ifdef CONFIG_PRINTK
+/* syslog_lock protects syslog_* variables and write access to clear_seq. */
+static DEFINE_SPINLOCK(syslog_lock);
 
-/*
- * Helper macros to lock/unlock logbuf_lock and switch between
- * printk-safe/unsafe modes.
- */
-#define logbuf_lock_irq()				\
-	do {						\
-		printk_safe_enter_irq();		\
-		raw_spin_lock(&logbuf_lock);		\
-	} while (0)
-
-#define logbuf_unlock_irq()				\
-	do {						\
-		raw_spin_unlock(&logbuf_lock);		\
-		printk_safe_exit_irq();			\
-	} while (0)
-
-#define logbuf_lock_irqsave(flags)			\
-	do {						\
-		printk_safe_enter_irqsave(flags);	\
-		raw_spin_lock(&logbuf_lock);		\
-	} while (0)
-
-#define logbuf_unlock_irqrestore(flags)		\
-	do {						\
-		raw_spin_unlock(&logbuf_lock);		\
-		printk_safe_exit_irqrestore(flags);	\
-	} while (0)
+/* Set to enable sync mode. Once set, it is never cleared. */
+static bool sync_mode;
 
-#ifdef CONFIG_PRINTK
 DECLARE_WAIT_QUEUE_HEAD(log_wait);
+/* All 3 protected by @syslog_lock. */
 /* the next printk record to read by syslog(READ) or /proc/kmsg */
 static u64 syslog_seq;
 static size_t syslog_partial;
 static bool syslog_time;
 
-/* the next printk record to write to the console */
-static u64 console_seq;
-static u64 exclusive_console_stop_seq;
-static unsigned long console_dropped;
+struct latched_seq {
+	seqcount_latch_t	latch;
+	u64			val[2];
+};
 
-/* the next printk record to read after the last 'clear' command */
-static u64 clear_seq;
+/*
+ * The next printk record to read after the last 'clear' command. There are
+ * two copies (updated with seqcount_latch) so that reads can locklessly
+ * access a valid value. Writers are synchronized by @syslog_lock.
+ */
+static struct latched_seq clear_seq = {
+	.latch		= SEQCNT_LATCH_ZERO(clear_seq.latch),
+	.val[0]		= 0,
+	.val[1]		= 0,
+};
 
 #ifdef CONFIG_PRINTK_CALLER
 #define PREFIX_MAX		48
 #else
 #define PREFIX_MAX		32
 #endif
+
+/* the maximum size allowed to be reserved for a record */
 #define LOG_LINE_MAX		(1024 - PREFIX_MAX)
 
 #define LOG_LEVEL(v)		((v) & 0x07)
@ kernel/printk/printk.c:413 @ static struct printk_ringbuffer *prb = &printk_rb_static;
  */
 static bool __printk_percpu_data_ready __read_mostly;
 
-bool printk_percpu_data_ready(void)
+static bool printk_percpu_data_ready(void)
 {
 	return __printk_percpu_data_ready;
 }
 
+/* Must be called under syslog_lock. */
+static void latched_seq_write(struct latched_seq *ls, u64 val)
+{
+	raw_write_seqcount_latch(&ls->latch);
+	ls->val[0] = val;
+	raw_write_seqcount_latch(&ls->latch);
+	ls->val[1] = val;
+}
+
+/* Can be called from any context. */
+static u64 latched_seq_read_nolock(struct latched_seq *ls)
+{
+	unsigned int seq;
+	unsigned int idx;
+	u64 val;
+
+	do {
+		seq = raw_read_seqcount_latch(&ls->latch);
+		idx = seq & 0x1;
+		val = ls->val[idx];
+	} while (read_seqcount_latch_retry(&ls->latch, seq));
+
+	return val;
+}
+
 /* Return log buffer address */
 char *log_buf_addr_get(void)
 {
@ kernel/printk/printk.c:482 @ static void truncate_msg(u16 *text_len, u16 *trunc_msg_len)
 		*trunc_msg_len = 0;
 }
 
-/* insert record into the buffer, discard old ones, update heads */
-static int log_store(u32 caller_id, int facility, int level,
-		     enum log_flags flags, u64 ts_nsec,
-		     const struct dev_printk_info *dev_info,
-		     const char *text, u16 text_len)
-{
-	struct prb_reserved_entry e;
-	struct printk_record r;
-	u16 trunc_msg_len = 0;
-
-	prb_rec_init_wr(&r, text_len);
-
-	if (!prb_reserve(&e, prb, &r)) {
-		/* truncate the message if it is too long for empty buffer */
-		truncate_msg(&text_len, &trunc_msg_len);
-		prb_rec_init_wr(&r, text_len + trunc_msg_len);
-		/* survive when the log buffer is too small for trunc_msg */
-		if (!prb_reserve(&e, prb, &r))
-			return 0;
-	}
-
-	/* fill message */
-	memcpy(&r.text_buf[0], text, text_len);
-	if (trunc_msg_len)
-		memcpy(&r.text_buf[text_len], trunc_msg, trunc_msg_len);
-	r.info->text_len = text_len + trunc_msg_len;
-	r.info->facility = facility;
-	r.info->level = level & 7;
-	r.info->flags = flags & 0x1f;
-	if (ts_nsec > 0)
-		r.info->ts_nsec = ts_nsec;
-	else
-		r.info->ts_nsec = local_clock();
-	r.info->caller_id = caller_id;
-	if (dev_info)
-		memcpy(&r.info->dev_info, dev_info, sizeof(r.info->dev_info));
-
-	/* A message without a trailing newline can be continued. */
-	if (!(flags & LOG_NEWLINE))
-		prb_commit(&e);
-	else
-		prb_final_commit(&e);
-
-	return (text_len + trunc_msg_len);
-}
-
 int dmesg_restrict = IS_ENABLED(CONFIG_SECURITY_DMESG_RESTRICT);
 
 static int syslog_action_restricted(int type)
@ kernel/printk/printk.c:610 @ static ssize_t msg_print_ext_body(char *buf, size_t size,
 
 /* /dev/kmsg - userspace message inject/listen interface */
 struct devkmsg_user {
-	u64 seq;
+	atomic64_t seq;
 	struct ratelimit_state rs;
 	struct mutex lock;
 	char buf[CONSOLE_EXT_LOG_MAX];
@ kernel/printk/printk.c:711 @ static ssize_t devkmsg_read(struct file *file, char __user *buf,
 	if (ret)
 		return ret;
 
-	logbuf_lock_irq();
-	if (!prb_read_valid(prb, user->seq, r)) {
+	if (!prb_read_valid(prb, atomic64_read(&user->seq), r)) {
 		if (file->f_flags & O_NONBLOCK) {
 			ret = -EAGAIN;
-			logbuf_unlock_irq();
 			goto out;
 		}
 
-		logbuf_unlock_irq();
 		ret = wait_event_interruptible(log_wait,
-					prb_read_valid(prb, user->seq, r));
+				prb_read_valid(prb, atomic64_read(&user->seq), r));
 		if (ret)
 			goto out;
-		logbuf_lock_irq();
 	}
 
-	if (r->info->seq != user->seq) {
+	if (r->info->seq != atomic64_read(&user->seq)) {
 		/* our last seen message is gone, return error and reset */
-		user->seq = r->info->seq;
+		atomic64_set(&user->seq, r->info->seq);
 		ret = -EPIPE;
-		logbuf_unlock_irq();
 		goto out;
 	}
 
@ kernel/printk/printk.c:735 @ static ssize_t devkmsg_read(struct file *file, char __user *buf,
 				  &r->text_buf[0], r->info->text_len,
 				  &r->info->dev_info);
 
-	user->seq = r->info->seq + 1;
-	logbuf_unlock_irq();
+	atomic64_set(&user->seq, r->info->seq + 1);
 
 	if (len > count) {
 		ret = -EINVAL;
@ kernel/printk/printk.c:770 @ static loff_t devkmsg_llseek(struct file *file, loff_t offset, int whence)
 	if (offset)
 		return -ESPIPE;
 
-	logbuf_lock_irq();
 	switch (whence) {
 	case SEEK_SET:
 		/* the first record */
-		user->seq = prb_first_valid_seq(prb);
+		atomic64_set(&user->seq, prb_first_valid_seq(prb));
 		break;
 	case SEEK_DATA:
 		/*
@ kernel/printk/printk.c:781 @ static loff_t devkmsg_llseek(struct file *file, loff_t offset, int whence)
 		 * like issued by 'dmesg -c'. Reading /dev/kmsg itself
 		 * changes no global state, and does not clear anything.
 		 */
-		user->seq = clear_seq;
+		atomic64_set(&user->seq, latched_seq_read_nolock(&clear_seq));
 		break;
 	case SEEK_END:
 		/* after the last record */
-		user->seq = prb_next_seq(prb);
+		atomic64_set(&user->seq, prb_next_seq(prb));
 		break;
 	default:
 		ret = -EINVAL;
 	}
-	logbuf_unlock_irq();
 	return ret;
 }
 
@ kernel/printk/printk.c:804 @ static __poll_t devkmsg_poll(struct file *file, poll_table *wait)
 
 	poll_wait(file, &log_wait, wait);
 
-	logbuf_lock_irq();
-	if (prb_read_valid_info(prb, user->seq, &info, NULL)) {
+	if (prb_read_valid_info(prb, atomic64_read(&user->seq), &info, NULL)) {
 		/* return error when data has vanished underneath us */
-		if (info.seq != user->seq)
+		if (info.seq != atomic64_read(&user->seq))
 			ret = EPOLLIN|EPOLLRDNORM|EPOLLERR|EPOLLPRI;
 		else
 			ret = EPOLLIN|EPOLLRDNORM;
 	}
-	logbuf_unlock_irq();
 
 	return ret;
 }
@ kernel/printk/printk.c:843 @ static int devkmsg_open(struct inode *inode, struct file *file)
 	prb_rec_init_rd(&user->record, &user->info,
 			&user->text_buf[0], sizeof(user->text_buf));
 
-	logbuf_lock_irq();
-	user->seq = prb_first_valid_seq(prb);
-	logbuf_unlock_irq();
+	atomic64_set(&user->seq, prb_first_valid_seq(prb));
 
 	file->private_data = user;
 	return 0;
@ kernel/printk/printk.c:935 @ void log_buf_vmcoreinfo_setup(void)
 
 	VMCOREINFO_SIZE(atomic_long_t);
 	VMCOREINFO_TYPE_OFFSET(atomic_long_t, counter);
+
+	VMCOREINFO_STRUCT_SIZE(latched_seq);
+	VMCOREINFO_OFFSET(latched_seq, val);
 }
 #endif
 
@ kernel/printk/printk.c:1009 @ static inline void log_buf_add_cpu(void) {}
 
 static void __init set_percpu_data_ready(void)
 {
-	printk_safe_init();
-	/* Make sure we set this flag only after printk_safe() init is done */
-	barrier();
 	__printk_percpu_data_ready = true;
 }
 
@ kernel/printk/printk.c:1048 @ void __init setup_log_buf(int early)
 	struct printk_record r;
 	size_t new_descs_size;
 	size_t new_infos_size;
-	unsigned long flags;
 	char *new_log_buf;
 	unsigned int free;
 	u64 seq;
@ kernel/printk/printk.c:1105 @ void __init setup_log_buf(int early)
 		 new_descs, ilog2(new_descs_count),
 		 new_infos);
 
-	logbuf_lock_irqsave(flags);
-
 	log_buf_len = new_log_buf_len;
 	log_buf = new_log_buf;
 	new_log_buf_len = 0;
@ kernel/printk/printk.c:1120 @ void __init setup_log_buf(int early)
 	 */
 	prb = &printk_rb_dynamic;
 
-	logbuf_unlock_irqrestore(flags);
-
 	if (seq != prb_next_seq(&printk_rb_static)) {
 		pr_err("dropped %llu messages\n",
 		       prb_next_seq(&printk_rb_static) - seq);
@ kernel/printk/printk.c:1396 @ static size_t get_record_print_text_size(struct printk_info *info,
 	return ((prefix_len * line_count) + info->text_len + 1);
 }
 
+/*
+ * Beginning with @start_seq, find the first record where it and all following
+ * records up to (but not including) @max_seq fit into @size.
+ *
+ * @max_seq is simply an upper bound and does not need to exist. If the caller
+ * does not require an upper bound, -1 can be used for @max_seq.
+ */
+static u64 find_first_fitting_seq(u64 start_seq, u64 max_seq, size_t size,
+				  bool syslog, bool time)
+{
+	struct printk_info info;
+	unsigned int line_count;
+	size_t len = 0;
+	u64 seq;
+
+	/* Determine the size of the records up to @max_seq. */
+	prb_for_each_info(start_seq, prb, seq, &info, &line_count) {
+		if (info.seq >= max_seq)
+			break;
+		len += get_record_print_text_size(&info, line_count, syslog, time);
+	}
+
+	/*
+	 * Adjust the upper bound for the next loop to avoid subtracting
+	 * lengths that were never added.
+	 */
+	if (seq < max_seq)
+		max_seq = seq;
+
+	/*
+	 * Move first record forward until length fits into the buffer. Ignore
+	 * newest messages that were not counted in the above cycle. Messages
+	 * might appear and get lost in the meantime. This is a best effort
+	 * that prevents an infinite loop that could occur with a retry.
+	 */
+	prb_for_each_info(start_seq, prb, seq, &info, &line_count) {
+		if (len <= size || info.seq >= max_seq)
+			break;
+		len -= get_record_print_text_size(&info, line_count, syslog, time);
+	}
+
+	return seq;
+}
+
 static int syslog_print(char __user *buf, int size)
 {
 	struct printk_info info;
@ kernel/printk/printk.c:1447 @ static int syslog_print(char __user *buf, int size)
 	char *text;
 	int len = 0;
 
-	text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL);
+	text = kmalloc(CONSOLE_LOG_MAX, GFP_KERNEL);
 	if (!text)
 		return -ENOMEM;
 
-	prb_rec_init_rd(&r, &info, text, LOG_LINE_MAX + PREFIX_MAX);
+	prb_rec_init_rd(&r, &info, text, CONSOLE_LOG_MAX);
 
 	while (size > 0) {
 		size_t n;
 		size_t skip;
 
-		logbuf_lock_irq();
+		spin_lock_irq(&syslog_lock);
 		if (!prb_read_valid(prb, syslog_seq, &r)) {
-			logbuf_unlock_irq();
+			spin_unlock_irq(&syslog_lock);
 			break;
 		}
 		if (r.info->seq != syslog_seq) {
@ kernel/printk/printk.c:1488 @ static int syslog_print(char __user *buf, int size)
 			syslog_partial += n;
 		} else
 			n = 0;
-		logbuf_unlock_irq();
+		spin_unlock_irq(&syslog_lock);
 
 		if (!n)
 			break;
@ kernel/printk/printk.c:1511 @ static int syslog_print(char __user *buf, int size)
 static int syslog_print_all(char __user *buf, int size, bool clear)
 {
 	struct printk_info info;
-	unsigned int line_count;
 	struct printk_record r;
 	char *text;
 	int len = 0;
 	u64 seq;
 	bool time;
 
-	text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL);
+	text = kmalloc(CONSOLE_LOG_MAX, GFP_KERNEL);
 	if (!text)
 		return -ENOMEM;
 
 	time = printk_time;
-	logbuf_lock_irq();
 	/*
 	 * Find first record that fits, including all following records,
 	 * into the user-provided buffer for this dump.
 	 */
-	prb_for_each_info(clear_seq, prb, seq, &info, &line_count)
-		len += get_record_print_text_size(&info, line_count, true, time);
-
-	/* move first record forward until length fits into the buffer */
-	prb_for_each_info(clear_seq, prb, seq, &info, &line_count) {
-		if (len <= size)
-			break;
-		len -= get_record_print_text_size(&info, line_count, true, time);
-	}
+	seq = find_first_fitting_seq(latched_seq_read_nolock(&clear_seq), -1,
+				     size, true, time);
 
-	prb_rec_init_rd(&r, &info, text, LOG_LINE_MAX + PREFIX_MAX);
+	prb_rec_init_rd(&r, &info, text, CONSOLE_LOG_MAX);
 
 	len = 0;
 	prb_for_each_record(seq, prb, seq, &r) {
@ kernel/printk/printk.c:1542 @ static int syslog_print_all(char __user *buf, int size, bool clear)
 			break;
 		}
 
-		logbuf_unlock_irq();
 		if (copy_to_user(buf + len, text, textlen))
 			len = -EFAULT;
 		else
 			len += textlen;
-		logbuf_lock_irq();
 
 		if (len < 0)
 			break;
 	}
 
-	if (clear)
-		clear_seq = seq;
-	logbuf_unlock_irq();
+	if (clear) {
+		spin_lock_irq(&syslog_lock);
+		latched_seq_write(&clear_seq, seq);
+		spin_unlock_irq(&syslog_lock);
+	}
 
 	kfree(text);
 	return len;
@ kernel/printk/printk.c:1563 @ static int syslog_print_all(char __user *buf, int size, bool clear)
 
 static void syslog_clear(void)
 {
-	logbuf_lock_irq();
-	clear_seq = prb_next_seq(prb);
-	logbuf_unlock_irq();
+	spin_lock_irq(&syslog_lock);
+	latched_seq_write(&clear_seq, prb_next_seq(prb));
+	spin_unlock_irq(&syslog_lock);
+}
+
+/* Return a consistent copy of @syslog_seq. */
+static u64 read_syslog_seq_irq(void)
+{
+	u64 seq;
+
+	spin_lock_irq(&syslog_lock);
+	seq = syslog_seq;
+	spin_unlock_irq(&syslog_lock);
+
+	return seq;
 }
 
 int do_syslog(int type, char __user *buf, int len, int source)
@ kernel/printk/printk.c:1603 @ int do_syslog(int type, char __user *buf, int len, int source)
 			return 0;
 		if (!access_ok(buf, len))
 			return -EFAULT;
+
 		error = wait_event_interruptible(log_wait,
-				prb_read_valid(prb, syslog_seq, NULL));
+				prb_read_valid(prb, read_syslog_seq_irq(), NULL));
 		if (error)
 			return error;
 		error = syslog_print(buf, len);
@ kernel/printk/printk.c:1653 @ int do_syslog(int type, char __user *buf, int len, int source)
 		break;
 	/* Number of chars in the log buffer */
 	case SYSLOG_ACTION_SIZE_UNREAD:
-		logbuf_lock_irq();
+		spin_lock_irq(&syslog_lock);
 		if (!prb_read_valid_info(prb, syslog_seq, &info, NULL)) {
 			/* No unread messages. */
-			logbuf_unlock_irq();
+			spin_unlock_irq(&syslog_lock);
 			return 0;
 		}
 		if (info.seq != syslog_seq) {
@ kernel/printk/printk.c:1684 @ int do_syslog(int type, char __user *buf, int len, int source)
 			}
 			error -= syslog_partial;
 		}
-		logbuf_unlock_irq();
+		spin_unlock_irq(&syslog_lock);
 		break;
 	/* Size of the log buffer */
 	case SYSLOG_ACTION_SIZE_BUFFER:
@ kernel/printk/printk.c:1703 @ SYSCALL_DEFINE3(syslog, int, type, char __user *, buf, int, len)
 	return do_syslog(type, buf, len, SYSLOG_FROM_READER);
 }
 
-/*
- * Special console_lock variants that help to reduce the risk of soft-lockups.
- * They allow to pass console_lock to another printk() call using a busy wait.
- */
-
-#ifdef CONFIG_LOCKDEP
-static struct lockdep_map console_owner_dep_map = {
-	.name = "console_owner"
-};
-#endif
-
-static DEFINE_RAW_SPINLOCK(console_owner_lock);
-static struct task_struct *console_owner;
-static bool console_waiter;
+int printk_delay_msec __read_mostly;
 
-/**
- * console_lock_spinning_enable - mark beginning of code where another
- *	thread might safely busy wait
- *
- * This basically converts console_lock into a spinlock. This marks
- * the section where the console_lock owner can not sleep, because
- * there may be a waiter spinning (like a spinlock). Also it must be
- * ready to hand over the lock at the end of the section.
- */
-static void console_lock_spinning_enable(void)
+static inline void printk_delay(int level)
 {
-	raw_spin_lock(&console_owner_lock);
-	console_owner = current;
-	raw_spin_unlock(&console_owner_lock);
+	boot_delay_msec(level);
+
+	if (unlikely(printk_delay_msec)) {
+		int m = printk_delay_msec;
 
-	/* The waiter may spin on us after setting console_owner */
-	spin_acquire(&console_owner_dep_map, 0, 0, _THIS_IP_);
+		while (m--) {
+			mdelay(1);
+			touch_nmi_watchdog();
+		}
+	}
 }
 
-/**
- * console_lock_spinning_disable_and_check - mark end of code where another
- *	thread was able to busy wait and check if there is a waiter
- *
- * This is called at the end of the section where spinning is allowed.
- * It has two functions. First, it is a signal that it is no longer
- * safe to start busy waiting for the lock. Second, it checks if
- * there is a busy waiter and passes the lock rights to her.
- *
- * Important: Callers lose the lock if there was a busy waiter.
- *	They must not touch items synchronized by console_lock
- *	in this case.
- *
- * Return: 1 if the lock rights were passed, 0 otherwise.
- */
-static int console_lock_spinning_disable_and_check(void)
+static bool kernel_sync_mode(void)
 {
-	int waiter;
+	return (oops_in_progress || sync_mode);
+}
 
-	raw_spin_lock(&console_owner_lock);
-	waiter = READ_ONCE(console_waiter);
-	console_owner = NULL;
-	raw_spin_unlock(&console_owner_lock);
+static bool console_can_sync(struct console *con)
+{
+	if (!(con->flags & CON_ENABLED))
+		return false;
+	if (con->write_atomic && kernel_sync_mode())
+		return true;
+	if (con->write_atomic && (con->flags & CON_HANDOVER) && !con->thread)
+		return true;
+	if (con->write && (con->flags & CON_BOOT) && !con->thread)
+		return true;
+	return false;
+}
 
-	if (!waiter) {
-		spin_release(&console_owner_dep_map, _THIS_IP_);
-		return 0;
-	}
+static bool call_sync_console_driver(struct console *con, const char *text, size_t text_len)
+{
+	if (!(con->flags & CON_ENABLED))
+		return false;
+	if (con->write_atomic && kernel_sync_mode())
+		con->write_atomic(con, text, text_len);
+	else if (con->write_atomic && (con->flags & CON_HANDOVER) && !con->thread)
+		con->write_atomic(con, text, text_len);
+	else if (con->write && (con->flags & CON_BOOT) && !con->thread)
+		con->write(con, text, text_len);
+	else
+		return false;
 
-	/* The waiter is now free to continue */
-	WRITE_ONCE(console_waiter, false);
+	return true;
+}
 
-	spin_release(&console_owner_dep_map, _THIS_IP_);
+static bool have_atomic_console(void)
+{
+	struct console *con;
 
-	/*
-	 * Hand off console_lock to waiter. The waiter will perform
-	 * the up(). After this, the waiter is the console_lock owner.
-	 */
-	mutex_release(&console_lock_dep_map, _THIS_IP_);
-	return 1;
+	for_each_console(con) {
+		if (!(con->flags & CON_ENABLED))
+			continue;
+		if (con->write_atomic)
+			return true;
+	}
+	return false;
 }
 
-/**
- * console_trylock_spinning - try to get console_lock by busy waiting
- *
- * This allows to busy wait for the console_lock when the current
- * owner is running in specially marked sections. It means that
- * the current owner is running and cannot reschedule until it
- * is ready to lose the lock.
- *
- * Return: 1 if we got the lock, 0 othrewise
- */
-static int console_trylock_spinning(void)
+static bool print_sync(struct console *con, u64 *seq)
 {
-	struct task_struct *owner = NULL;
-	bool waiter;
-	bool spin = false;
-	unsigned long flags;
+	struct printk_info info;
+	struct printk_record r;
+	size_t text_len;
 
-	if (console_trylock())
-		return 1;
+	prb_rec_init_rd(&r, &info, &con->sync_buf[0], sizeof(con->sync_buf));
 
-	printk_safe_enter_irqsave(flags);
+	if (!prb_read_valid(prb, *seq, &r))
+		return false;
 
-	raw_spin_lock(&console_owner_lock);
-	owner = READ_ONCE(console_owner);
-	waiter = READ_ONCE(console_waiter);
-	if (!waiter && owner && owner != current) {
-		WRITE_ONCE(console_waiter, true);
-		spin = true;
-	}
-	raw_spin_unlock(&console_owner_lock);
+	text_len = record_print_text(&r, console_msg_format & MSG_FORMAT_SYSLOG, printk_time);
 
-	/*
-	 * If there is an active printk() writing to the
-	 * consoles, instead of having it write our data too,
-	 * see if we can offload that load from the active
-	 * printer, and do some printing ourselves.
-	 * Go into a spin only if there isn't already a waiter
-	 * spinning, and there is an active printer, and
-	 * that active printer isn't us (recursive printk?).
-	 */
-	if (!spin) {
-		printk_safe_exit_irqrestore(flags);
-		return 0;
-	}
+	if (!call_sync_console_driver(con, &con->sync_buf[0], text_len))
+		return false;
 
-	/* We spin waiting for the owner to release us */
-	spin_acquire(&console_owner_dep_map, 0, 0, _THIS_IP_);
-	/* Owner will clear console_waiter on hand off */
-	while (READ_ONCE(console_waiter))
-		cpu_relax();
-	spin_release(&console_owner_dep_map, _THIS_IP_);
+	*seq = r.info->seq;
 
-	printk_safe_exit_irqrestore(flags);
-	/*
-	 * The owner passed the console lock to us.
-	 * Since we did not spin on console lock, annotate
-	 * this as a trylock. Otherwise lockdep will
-	 * complain.
-	 */
-	mutex_acquire(&console_lock_dep_map, 0, 1, _THIS_IP_);
+	touch_softlockup_watchdog_sync();
+	clocksource_touch_watchdog();
+	rcu_cpu_stall_reset();
+	touch_nmi_watchdog();
 
-	return 1;
+	if (text_len)
+		printk_delay(r.info->level);
+
+	return true;
 }
 
-/*
- * Call the console drivers, asking them to write out
- * log_buf[start] to log_buf[end - 1].
- * The console_lock must be held.
- */
-static void call_console_drivers(const char *ext_text, size_t ext_len,
-				 const char *text, size_t len)
+static void print_sync_until(struct console *con, u64 seq)
 {
-	static char dropped_text[64];
-	size_t dropped_len = 0;
-	struct console *con;
+	unsigned int flags;
+	u64 printk_seq;
+
+	console_atomic_lock(&flags);
+	for (;;) {
+		printk_seq = atomic64_read(&con->printk_seq);
+		if (printk_seq >= seq)
+			break;
+		if (!print_sync(con, &printk_seq))
+			break;
+		atomic64_set(&con->printk_seq, printk_seq + 1);
+	}
+	console_atomic_unlock(flags);
+}
 
-	trace_console_rcuidle(text, len);
+#ifdef CONFIG_PRINTK_NMI
+#define NUM_RECURSION_CTX 2
+#else
+#define NUM_RECURSION_CTX 1
+#endif
 
-	if (!console_drivers)
-		return;
+struct printk_recursion {
+	char	count[NUM_RECURSION_CTX];
+};
 
-	if (console_dropped) {
-		dropped_len = snprintf(dropped_text, sizeof(dropped_text),
-				       "** %lu printk messages dropped **\n",
-				       console_dropped);
-		console_dropped = 0;
-	}
+static DEFINE_PER_CPU(struct printk_recursion, percpu_printk_recursion);
+static char printk_recursion_count[NUM_RECURSION_CTX];
 
-	for_each_console(con) {
-		if (exclusive_console && con != exclusive_console)
-			continue;
-		if (!(con->flags & CON_ENABLED))
-			continue;
-		if (!con->write)
-			continue;
-		if (!cpu_online(smp_processor_id()) &&
-		    !(con->flags & CON_ANYTIME))
-			continue;
-		if (con->flags & CON_EXTENDED)
-			con->write(con, ext_text, ext_len);
-		else {
-			if (dropped_len)
-				con->write(con, dropped_text, dropped_len);
-			con->write(con, text, len);
-		}
+static char *printk_recursion_counter(void)
+{
+	struct printk_recursion *rec;
+	char *count;
+
+	if (!printk_percpu_data_ready()) {
+		count = &printk_recursion_count[0];
+	} else {
+		rec = this_cpu_ptr(&percpu_printk_recursion);
+
+		count = &rec->count[0];
 	}
-}
 
-int printk_delay_msec __read_mostly;
+#ifdef CONFIG_PRINTK_NMI
+	if (in_nmi())
+		count++;
+#endif
+
+	return count;
+}
 
-static inline void printk_delay(void)
+static bool printk_enter_irqsave(unsigned long *flags)
 {
-	if (unlikely(printk_delay_msec)) {
-		int m = printk_delay_msec;
+	char *count;
 
-		while (m--) {
-			mdelay(1);
-			touch_nmi_watchdog();
-		}
+	local_irq_save(*flags);
+	count = printk_recursion_counter();
+	/* Only 1 level of recursion allowed. */
+	if (*count > 1) {
+		local_irq_restore(*flags);
+		return false;
 	}
+	(*count)++;
+
+	return true;
+}
+
+static void printk_exit_irqrestore(unsigned long flags)
+{
+	char *count;
+
+	count = printk_recursion_counter();
+	(*count)--;
+	local_irq_restore(flags);
 }
 
 static inline u32 printk_caller_id(void)
@ kernel/printk/printk.c:1877 @ static inline u32 printk_caller_id(void)
 		0x80000000 + raw_smp_processor_id();
 }
 
-static size_t log_output(int facility, int level, enum log_flags lflags,
-			 const struct dev_printk_info *dev_info,
-			 char *text, size_t text_len)
+/**
+ * parse_prefix - Parse level and control flags.
+ *
+ * @text:     The terminated text message.
+ * @level:    A pointer to the current level value, will be updated.
+ * @lflags:   A pointer to the current log flags, will be updated.
+ *
+ * @level may be NULL if the caller is not interested in the parsed value.
+ * Otherwise the variable pointed to by @level must be set to
+ * LOGLEVEL_DEFAULT in order to be updated with the parsed value.
+ *
+ * @lflags may be NULL if the caller is not interested in the parsed value.
+ * Otherwise the variable pointed to by @lflags will be OR'd with the parsed
+ * value.
+ *
+ * Return: The length of the parsed level and control flags.
+ */
+static u16 parse_prefix(char *text, int *level, enum log_flags *lflags)
 {
-	const u32 caller_id = printk_caller_id();
+	u16 prefix_len = 0;
+	int kern_level;
 
-	if (lflags & LOG_CONT) {
-		struct prb_reserved_entry e;
-		struct printk_record r;
+	while (*text) {
+		kern_level = printk_get_level(text);
+		if (!kern_level)
+			break;
 
-		prb_rec_init_wr(&r, text_len);
-		if (prb_reserve_in_last(&e, prb, &r, caller_id, LOG_LINE_MAX)) {
-			memcpy(&r.text_buf[r.info->text_len], text, text_len);
-			r.info->text_len += text_len;
-			if (lflags & LOG_NEWLINE) {
-				r.info->flags |= LOG_NEWLINE;
-				prb_final_commit(&e);
-			} else {
-				prb_commit(&e);
-			}
-			return text_len;
+		switch (kern_level) {
+		case '0' ... '7':
+			if (level && *level == LOGLEVEL_DEFAULT)
+				*level = kern_level - '0';
+			break;
+		case 'c':	/* KERN_CONT */
+			if (lflags)
+				*lflags |= LOG_CONT;
 		}
+
+		prefix_len += 2;
+		text += 2;
 	}
 
-	/* Store it in the record log */
-	return log_store(caller_id, facility, level, lflags, 0,
-			 dev_info, text, text_len);
+	return prefix_len;
 }
 
-/* Must be called under logbuf_lock. */
-int vprintk_store(int facility, int level,
-		  const struct dev_printk_info *dev_info,
-		  const char *fmt, va_list args)
+static u16 printk_sprint(char *text, u16 size, int facility, enum log_flags *lflags,
+			 const char *fmt, va_list args)
 {
-	static char textbuf[LOG_LINE_MAX];
-	char *text = textbuf;
-	size_t text_len;
-	enum log_flags lflags = 0;
+	u16 text_len;
 
-	/*
-	 * The printf needs to come first; we need the syslog
-	 * prefix which might be passed-in as a parameter.
-	 */
-	text_len = vscnprintf(text, sizeof(textbuf), fmt, args);
+	text_len = vscnprintf(text, size, fmt, args);
 
-	/* mark and strip a trailing newline */
-	if (text_len && text[text_len-1] == '\n') {
+	/* Mark and strip a trailing newline. */
+	if (text_len && text[text_len - 1] == '\n') {
 		text_len--;
-		lflags |= LOG_NEWLINE;
+		*lflags |= LOG_NEWLINE;
 	}
 
-	/* strip kernel syslog prefix and extract log level or control flags */
+	/* Strip log level and control flags. */
 	if (facility == 0) {
-		int kern_level;
-
-		while ((kern_level = printk_get_level(text)) != 0) {
-			switch (kern_level) {
-			case '0' ... '7':
-				if (level == LOGLEVEL_DEFAULT)
-					level = kern_level - '0';
-				break;
-			case 'c':	/* KERN_CONT */
-				lflags |= LOG_CONT;
-			}
+		u16 prefix_len;
 
-			text_len -= 2;
-			text += 2;
+		prefix_len = parse_prefix(text, NULL, NULL);
+		if (prefix_len) {
+			text_len -= prefix_len;
+			memmove(text, text + prefix_len, text_len);
 		}
 	}
 
-	if (level == LOGLEVEL_DEFAULT)
-		level = default_message_loglevel;
-
-	if (dev_info)
-		lflags |= LOG_NEWLINE;
-
-	return log_output(facility, level, lflags, dev_info, text, text_len);
+	return text_len;
 }
 
-asmlinkage int vprintk_emit(int facility, int level,
-			    const struct dev_printk_info *dev_info,
-			    const char *fmt, va_list args)
+__printf(4, 0)
+static int vprintk_store(int facility, int level,
+			 const struct dev_printk_info *dev_info,
+			 const char *fmt, va_list args)
 {
-	int printed_len;
-	bool in_sched = false;
-	unsigned long flags;
-
-	/* Suppress unimportant messages after panic happens */
-	if (unlikely(suppress_printk))
+	const u32 caller_id = printk_caller_id();
+	struct prb_reserved_entry e;
+	enum log_flags lflags = 0;
+	bool final_commit = false;
+	struct printk_record r;
+	unsigned long irqflags;
+	u16 trunc_msg_len = 0;
+	char prefix_buf[8];
+	u16 reserve_size;
+	va_list args2;
+	u16 text_len;
+	int ret = 0;
+	u64 ts_nsec;
+	u64 seq;
+
+	/*
+	 * Since the duration of printk() can vary depending on the message
+	 * and state of the ringbuffer, grab the timestamp now so that it is
+	 * close to the call of printk(). This provides a more deterministic
+	 * timestamp with respect to the caller.
+	 */
+	ts_nsec = local_clock();
+
+	if (!printk_enter_irqsave(&irqflags))
 		return 0;
 
-	if (level == LOGLEVEL_SCHED) {
-		level = LOGLEVEL_DEFAULT;
-		in_sched = true;
+	/*
+	 * The sprintf needs to come first since the syslog prefix might be
+	 * passed in as a parameter. An extra byte must be reserved so that
+	 * later the vscnprintf() into the reserved buffer has room for the
+	 * terminating '\0', which is not counted by vsnprintf().
+	 */
+	va_copy(args2, args);
+	reserve_size = vsnprintf(&prefix_buf[0], sizeof(prefix_buf), fmt, args2) + 1;
+	va_end(args2);
+
+	if (reserve_size > LOG_LINE_MAX)
+		reserve_size = LOG_LINE_MAX;
+
+	/* Extract log level or control flags. */
+	if (facility == 0)
+		parse_prefix(&prefix_buf[0], &level, &lflags);
+
+	if (level == LOGLEVEL_DEFAULT)
+		level = default_message_loglevel;
+
+	if (dev_info)
+		lflags |= LOG_NEWLINE;
+
+	if (lflags & LOG_CONT) {
+		prb_rec_init_wr(&r, reserve_size);
+		if (prb_reserve_in_last(&e, prb, &r, caller_id, LOG_LINE_MAX)) {
+			seq = r.info->seq;
+			text_len = printk_sprint(&r.text_buf[r.info->text_len], reserve_size,
+						 facility, &lflags, fmt, args);
+			r.info->text_len += text_len;
+
+			if (lflags & LOG_NEWLINE) {
+				r.info->flags |= LOG_NEWLINE;
+				prb_final_commit(&e);
+				final_commit = true;
+			} else {
+				prb_commit(&e);
+			}
+
+			ret = text_len;
+			goto out;
+		}
 	}
 
-	boot_delay_msec(level);
-	printk_delay();
+	/*
+	 * Explicitly initialize the record before every prb_reserve() call.
+	 * prb_reserve_in_last() and prb_reserve() purposely invalidate the
+	 * structure when they fail.
+	 */
+	prb_rec_init_wr(&r, reserve_size);
+	if (!prb_reserve(&e, prb, &r)) {
+		/* truncate the message if it is too long for empty buffer */
+		truncate_msg(&reserve_size, &trunc_msg_len);
 
-	/* This stops the holder of console_sem just where we want him */
-	logbuf_lock_irqsave(flags);
-	printed_len = vprintk_store(facility, level, dev_info, fmt, args);
-	logbuf_unlock_irqrestore(flags);
+		prb_rec_init_wr(&r, reserve_size + trunc_msg_len);
+		if (!prb_reserve(&e, prb, &r))
+			goto out;
+	}
 
-	/* If called from the scheduler, we can not call up(). */
-	if (!in_sched) {
-		/*
-		 * Disable preemption to avoid being preempted while holding
-		 * console_sem which would prevent anyone from printing to
-		 * console
-		 */
-		preempt_disable();
-		/*
-		 * Try to acquire and then immediately release the console
-		 * semaphore.  The release will print out buffers and wake up
-		 * /dev/kmsg and syslog() users.
-		 */
-		if (console_trylock_spinning())
-			console_unlock();
-		preempt_enable();
+	seq = r.info->seq;
+
+	/* fill message */
+	text_len = printk_sprint(&r.text_buf[0], reserve_size, facility, &lflags, fmt, args);
+	if (trunc_msg_len)
+		memcpy(&r.text_buf[text_len], trunc_msg, trunc_msg_len);
+	r.info->text_len = text_len + trunc_msg_len;
+	r.info->facility = facility;
+	r.info->level = level & 7;
+	r.info->flags = lflags & 0x1f;
+	r.info->ts_nsec = ts_nsec;
+	r.info->caller_id = caller_id;
+	if (dev_info)
+		memcpy(&r.info->dev_info, dev_info, sizeof(r.info->dev_info));
+
+	/* A message without a trailing newline can be continued. */
+	if (!(lflags & LOG_NEWLINE)) {
+		prb_commit(&e);
+	} else {
+		prb_final_commit(&e);
+		final_commit = true;
 	}
 
+	ret = text_len + trunc_msg_len;
+out:
+	/* only the kernel may perform synchronous printing */
+	if (facility == 0 && final_commit) {
+		struct console *con;
+
+		for_each_console(con) {
+			if (console_can_sync(con))
+				print_sync_until(con, seq + 1);
+		}
+	}
+
+	printk_exit_irqrestore(irqflags);
+	return ret;
+}
+
+asmlinkage int vprintk_emit(int facility, int level,
+			    const struct dev_printk_info *dev_info,
+			    const char *fmt, va_list args)
+{
+	int printed_len;
+
+	/* Suppress unimportant messages after panic happens */
+	if (unlikely(suppress_printk))
+		return 0;
+
+	if (level == LOGLEVEL_SCHED)
+		level = LOGLEVEL_DEFAULT;
+
+	printed_len = vprintk_store(facility, level, dev_info, fmt, args);
+
 	wake_up_klogd();
 	return printed_len;
 }
 EXPORT_SYMBOL(vprintk_emit);
 
-asmlinkage int vprintk(const char *fmt, va_list args)
+__printf(1, 0)
+static int vprintk_default(const char *fmt, va_list args)
 {
-	return vprintk_func(fmt, args);
+	return vprintk_emit(0, LOGLEVEL_DEFAULT, NULL, fmt, args);
 }
-EXPORT_SYMBOL(vprintk);
 
-int vprintk_default(const char *fmt, va_list args)
+__printf(1, 0)
+static int vprintk_func(const char *fmt, va_list args)
 {
-	return vprintk_emit(0, LOGLEVEL_DEFAULT, NULL, fmt, args);
+#ifdef CONFIG_KGDB_KDB
+	/* Allow to pass printk() to kdb but avoid a recursion. */
+	if (unlikely(kdb_trap_printk && kdb_printf_cpu < 0))
+		return vkdb_printf(KDB_MSGSRC_PRINTK, fmt, args);
+#endif
+	return vprintk_default(fmt, args);
+}
+
+asmlinkage int vprintk(const char *fmt, va_list args)
+{
+	return vprintk_func(fmt, args);
 }
-EXPORT_SYMBOL_GPL(vprintk_default);
+EXPORT_SYMBOL(vprintk);
 
 /**
  * printk - print a kernel message
@ kernel/printk/printk.c:2154 @ asmlinkage __visible int printk(const char *fmt, ...)
 }
 EXPORT_SYMBOL(printk);
 
-#else /* CONFIG_PRINTK */
+static int printk_kthread_func(void *data)
+{
+	struct console *con = data;
+	unsigned long dropped = 0;
+	char *dropped_text = NULL;
+	struct printk_info info;
+	struct printk_record r;
+	char *ext_text = NULL;
+	size_t dropped_len;
+	int ret = -ENOMEM;
+	char *text = NULL;
+	char *write_text;
+	u64 printk_seq;
+	size_t len;
+	int error;
+	u64 seq;
 
-#define LOG_LINE_MAX		0
-#define PREFIX_MAX		0
-#define printk_time		false
+	if (con->flags & CON_EXTENDED) {
+		ext_text = kmalloc(CONSOLE_EXT_LOG_MAX, GFP_KERNEL);
+		if (!ext_text)
+			goto out;
+	}
+	text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL);
+	dropped_text = kmalloc(64, GFP_KERNEL);
+	if (!text || !dropped_text)
+		goto out;
 
-#define prb_read_valid(rb, seq, r)	false
-#define prb_first_valid_seq(rb)		0
+	if (con->flags & CON_EXTENDED)
+		write_text = ext_text;
+	else
+		write_text = text;
 
-static u64 syslog_seq;
-static u64 console_seq;
-static u64 exclusive_console_stop_seq;
-static unsigned long console_dropped;
+	seq = atomic64_read(&con->printk_seq);
+
+	prb_rec_init_rd(&r, &info, text, LOG_LINE_MAX + PREFIX_MAX);
+
+	for (;;) {
+		error = wait_event_interruptible(log_wait,
+				prb_read_valid(prb, seq, &r) || kthread_should_stop());
 
-static size_t record_print_text(const struct printk_record *r,
-				bool syslog, bool time)
+		if (kthread_should_stop())
+			break;
+
+		if (error)
+			continue;
+
+		if (seq != r.info->seq) {
+			dropped += r.info->seq - seq;
+			seq = r.info->seq;
+		}
+
+		seq++;
+
+		if (!(con->flags & CON_ENABLED))
+			continue;
+
+		if (suppress_message_printing(r.info->level))
+			continue;
+
+		if (con->flags & CON_EXTENDED) {
+			len = info_print_ext_header(ext_text,
+				CONSOLE_EXT_LOG_MAX,
+				r.info);
+			len += msg_print_ext_body(ext_text + len,
+				CONSOLE_EXT_LOG_MAX - len,
+				&r.text_buf[0], r.info->text_len,
+				&r.info->dev_info);
+		} else {
+			len = record_print_text(&r,
+				console_msg_format & MSG_FORMAT_SYSLOG,
+				printk_time);
+		}
+
+		printk_seq = atomic64_read(&con->printk_seq);
+
+		console_lock();
+		console_may_schedule = 0;
+
+		if (kernel_sync_mode() && con->write_atomic) {
+			console_unlock();
+			break;
+		}
+
+		if (!(con->flags & CON_EXTENDED) && dropped) {
+			dropped_len = snprintf(dropped_text, 64,
+					       "** %lu printk messages dropped **\n",
+					       dropped);
+			dropped = 0;
+
+			con->write(con, dropped_text, dropped_len);
+			printk_delay(r.info->level);
+		}
+
+		con->write(con, write_text, len);
+		if (len)
+			printk_delay(r.info->level);
+
+		atomic64_cmpxchg_relaxed(&con->printk_seq, printk_seq, seq);
+
+		console_unlock();
+	}
+out:
+	kfree(dropped_text);
+	kfree(text);
+	kfree(ext_text);
+	pr_info("%sconsole [%s%d]: printing thread stopped\n",
+		(con->flags & CON_BOOT) ? "boot" : "",
+		con->name, con->index);
+	return ret;
+}
+
+/* Must be called within console_lock(). */
+static void start_printk_kthread(struct console *con)
 {
-	return 0;
+	con->thread = kthread_run(printk_kthread_func, con,
+				  "pr/%s%d", con->name, con->index);
+	if (IS_ERR(con->thread)) {
+		pr_err("%sconsole [%s%d]: unable to start printing thread\n",
+			(con->flags & CON_BOOT) ? "boot" : "",
+			con->name, con->index);
+		return;
+	}
+	pr_info("%sconsole [%s%d]: printing thread started\n",
+		(con->flags & CON_BOOT) ? "boot" : "",
+		con->name, con->index);
 }
-static ssize_t info_print_ext_header(char *buf, size_t size,
-				     struct printk_info *info)
+
+/* protected by console_lock */
+static bool kthreads_started;
+
+/* Must be called within console_lock(). */
+static void console_try_thread(struct console *con)
 {
-	return 0;
+	if (kthreads_started) {
+		start_printk_kthread(con);
+		return;
+	}
+
+	/*
+	 * The printing threads have not been started yet. If this console
+	 * can print synchronously, print all unprinted messages.
+	 */
+	if (console_can_sync(con))
+		print_sync_until(con, prb_next_seq(prb));
 }
-static ssize_t msg_print_ext_body(char *buf, size_t size,
-				  char *text, size_t text_len,
-				  struct dev_printk_info *dev_info) { return 0; }
-static void console_lock_spinning_enable(void) { }
-static int console_lock_spinning_disable_and_check(void) { return 0; }
-static void call_console_drivers(const char *ext_text, size_t ext_len,
-				 const char *text, size_t len) {}
-static bool suppress_message_printing(int level) { return false; }
+
+#else /* CONFIG_PRINTK */
+
+#define prb_first_valid_seq(rb)		0
+#define prb_next_seq(rb)		0
+
+#define console_try_thread(con)
 
 #endif /* CONFIG_PRINTK */
 
@ kernel/printk/printk.c:2550 @ int is_console_locked(void)
 }
 EXPORT_SYMBOL(is_console_locked);
 
-/*
- * Check if we have any console that is capable of printing while cpu is
- * booting or shutting down. Requires console_sem.
- */
-static int have_callable_console(void)
-{
-	struct console *con;
-
-	for_each_console(con)
-		if ((con->flags & CON_ENABLED) &&
-				(con->flags & CON_ANYTIME))
-			return 1;
-
-	return 0;
-}
-
-/*
- * Can we actually use the console at this time on this cpu?
- *
- * Console drivers may assume that per-cpu resources have been allocated. So
- * unless they're explicitly marked as being able to cope (CON_ANYTIME) don't
- * call them until this CPU is officially up.
- */
-static inline int can_use_console(void)
-{
-	return cpu_online(raw_smp_processor_id()) || have_callable_console();
-}
-
 /**
  * console_unlock - unlock the console system
  *
@ kernel/printk/printk.c:2566 @ static inline int can_use_console(void)
  */
 void console_unlock(void)
 {
-	static char ext_text[CONSOLE_EXT_LOG_MAX];
-	static char text[LOG_LINE_MAX + PREFIX_MAX];
-	unsigned long flags;
-	bool do_cond_resched, retry;
-	struct printk_info info;
-	struct printk_record r;
-
 	if (console_suspended) {
 		up_console_sem();
 		return;
 	}
 
-	prb_rec_init_rd(&r, &info, text, sizeof(text));
-
-	/*
-	 * Console drivers are called with interrupts disabled, so
-	 * @console_may_schedule should be cleared before; however, we may
-	 * end up dumping a lot of lines, for example, if called from
-	 * console registration path, and should invoke cond_resched()
-	 * between lines if allowable.  Not doing so can cause a very long
-	 * scheduling stall on a slow console leading to RCU stall and
-	 * softlockup warnings which exacerbate the issue with more
-	 * messages practically incapacitating the system.
-	 *
-	 * console_trylock() is not able to detect the preemptive
-	 * context reliably. Therefore the value must be stored before
-	 * and cleared after the "again" goto label.
-	 */
-	do_cond_resched = console_may_schedule;
-again:
-	console_may_schedule = 0;
-
-	/*
-	 * We released the console_sem lock, so we need to recheck if
-	 * cpu is online and (if not) is there at least one CON_ANYTIME
-	 * console.
-	 */
-	if (!can_use_console()) {
-		console_locked = 0;
-		up_console_sem();
-		return;
-	}
-
-	for (;;) {
-		size_t ext_len = 0;
-		size_t len;
-
-		printk_safe_enter_irqsave(flags);
-		raw_spin_lock(&logbuf_lock);
-skip:
-		if (!prb_read_valid(prb, console_seq, &r))
-			break;
-
-		if (console_seq != r.info->seq) {
-			console_dropped += r.info->seq - console_seq;
-			console_seq = r.info->seq;
-		}
-
-		if (suppress_message_printing(r.info->level)) {
-			/*
-			 * Skip record we have buffered and already printed
-			 * directly to the console when we received it, and
-			 * record that has level above the console loglevel.
-			 */
-			console_seq++;
-			goto skip;
-		}
-
-		/* Output to all consoles once old messages replayed. */
-		if (unlikely(exclusive_console &&
-			     console_seq >= exclusive_console_stop_seq)) {
-			exclusive_console = NULL;
-		}
-
-		/*
-		 * Handle extended console text first because later
-		 * record_print_text() will modify the record buffer in-place.
-		 */
-		if (nr_ext_console_drivers) {
-			ext_len = info_print_ext_header(ext_text,
-						sizeof(ext_text),
-						r.info);
-			ext_len += msg_print_ext_body(ext_text + ext_len,
-						sizeof(ext_text) - ext_len,
-						&r.text_buf[0],
-						r.info->text_len,
-						&r.info->dev_info);
-		}
-		len = record_print_text(&r,
-				console_msg_format & MSG_FORMAT_SYSLOG,
-				printk_time);
-		console_seq++;
-		raw_spin_unlock(&logbuf_lock);
-
-		/*
-		 * While actively printing out messages, if another printk()
-		 * were to occur on another CPU, it may wait for this one to
-		 * finish. This task can not be preempted if there is a
-		 * waiter waiting to take over.
-		 */
-		console_lock_spinning_enable();
-
-		stop_critical_timings();	/* don't trace print latency */
-		call_console_drivers(ext_text, ext_len, text, len);
-		start_critical_timings();
-
-		if (console_lock_spinning_disable_and_check()) {
-			printk_safe_exit_irqrestore(flags);
-			return;
-		}
-
-		printk_safe_exit_irqrestore(flags);
-
-		if (do_cond_resched)
-			cond_resched();
-	}
-
 	console_locked = 0;
 
-	raw_spin_unlock(&logbuf_lock);
-
 	up_console_sem();
-
-	/*
-	 * Someone could have filled up the buffer again, so re-check if there's
-	 * something to flush. In case we cannot trylock the console_sem again,
-	 * there's a new owner and the console_unlock() from them will do the
-	 * flush, no worries.
-	 */
-	raw_spin_lock(&logbuf_lock);
-	retry = prb_read_valid(prb, console_seq, NULL);
-	raw_spin_unlock(&logbuf_lock);
-	printk_safe_exit_irqrestore(flags);
-
-	if (retry && console_trylock())
-		goto again;
 }
 EXPORT_SYMBOL(console_unlock);
 
@ kernel/printk/printk.c:2623 @ void console_unblank(void)
  */
 void console_flush_on_panic(enum con_flush_mode mode)
 {
-	/*
-	 * If someone else is holding the console lock, trylock will fail
-	 * and may_schedule may be set.  Ignore and proceed to unlock so
-	 * that messages are flushed out.  As this can be called from any
-	 * context and we don't want to get preempted while flushing,
-	 * ensure may_schedule is cleared.
-	 */
-	console_trylock();
+	struct console *c;
+	u64 seq;
+
+	if (!console_trylock())
+		return;
+
 	console_may_schedule = 0;
 
 	if (mode == CONSOLE_REPLAY_ALL) {
-		unsigned long flags;
-
-		logbuf_lock_irqsave(flags);
-		console_seq = prb_first_valid_seq(prb);
-		logbuf_unlock_irqrestore(flags);
+		seq = prb_first_valid_seq(prb);
+		for_each_console(c)
+			atomic64_set(&c->printk_seq, seq);
 	}
+
 	console_unlock();
 }
 
@ kernel/printk/printk.c:2771 @ static int try_enable_new_console(struct console *newcon, bool user_specified)
  */
 void register_console(struct console *newcon)
 {
-	unsigned long flags;
 	struct console *bcon = NULL;
 	int err;
 
@ kernel/printk/printk.c:2794 @ void register_console(struct console *newcon)
 		}
 	}
 
+	newcon->thread = NULL;
+
 	if (console_drivers && console_drivers->flags & CON_BOOT)
 		bcon = console_drivers;
 
@ kernel/printk/printk.c:2837 @ void register_console(struct console *newcon)
 	 * the real console are the same physical device, it's annoying to
 	 * see the beginning boot messages twice
 	 */
-	if (bcon && ((newcon->flags & (CON_CONSDEV | CON_BOOT)) == CON_CONSDEV))
+	if (bcon && ((newcon->flags & (CON_CONSDEV | CON_BOOT)) == CON_CONSDEV)) {
 		newcon->flags &= ~CON_PRINTBUFFER;
+		newcon->flags |= CON_HANDOVER;
+	}
 
 	/*
 	 *	Put this console in the list - keep the
@ kernel/printk/printk.c:2862 @ void register_console(struct console *newcon)
 	if (newcon->flags & CON_EXTENDED)
 		nr_ext_console_drivers++;
 
-	if (newcon->flags & CON_PRINTBUFFER) {
-		/*
-		 * console_unlock(); will print out the buffered messages
-		 * for us.
-		 */
-		logbuf_lock_irqsave(flags);
-		/*
-		 * We're about to replay the log buffer.  Only do this to the
-		 * just-registered console to avoid excessive message spam to
-		 * the already-registered consoles.
-		 *
-		 * Set exclusive_console with disabled interrupts to reduce
-		 * race window with eventual console_flush_on_panic() that
-		 * ignores console_lock.
-		 */
-		exclusive_console = newcon;
-		exclusive_console_stop_seq = console_seq;
-		console_seq = syslog_seq;
-		logbuf_unlock_irqrestore(flags);
-	}
+	if (newcon->flags & CON_PRINTBUFFER)
+		atomic64_set(&newcon->printk_seq, 0);
+	else
+		atomic64_set(&newcon->printk_seq, prb_next_seq(prb));
+
+	console_try_thread(newcon);
 	console_unlock();
 	console_sysfs_notify();
 
@ kernel/printk/printk.c:2941 @ int unregister_console(struct console *console)
 	console_unlock();
 	console_sysfs_notify();
 
+	if (console->thread && !IS_ERR(console->thread))
+		kthread_stop(console->thread);
+
 	if (console->exit)
 		res = console->exit(console);
 
@ kernel/printk/printk.c:3026 @ static int __init printk_late_init(void)
 			unregister_console(con);
 		}
 	}
+
+#ifdef CONFIG_PRINTK
+	console_lock();
+	for_each_console(con)
+		start_printk_kthread(con);
+	kthreads_started = true;
+	console_unlock();
+#endif
+
 	ret = cpuhp_setup_state_nocalls(CPUHP_PRINTK_DEAD, "printk:dead", NULL,
 					console_cpu_notify);
 	WARN_ON(ret < 0);
@ kernel/printk/printk.c:3050 @ late_initcall(printk_late_init);
  * Delayed printk version, for scheduler-internal messages:
  */
 #define PRINTK_PENDING_WAKEUP	0x01
-#define PRINTK_PENDING_OUTPUT	0x02
 
 static DEFINE_PER_CPU(int, printk_pending);
 
@ kernel/printk/printk.c:3057 @ static void wake_up_klogd_work_func(struct irq_work *irq_work)
 {
 	int pending = __this_cpu_xchg(printk_pending, 0);
 
-	if (pending & PRINTK_PENDING_OUTPUT) {
-		/* If trylock fails, someone else is doing the printing */
-		if (console_trylock())
-			console_unlock();
-	}
-
 	if (pending & PRINTK_PENDING_WAKEUP)
-		wake_up_interruptible(&log_wait);
+		wake_up_interruptible_all(&log_wait);
 }
 
 static DEFINE_PER_CPU(struct irq_work, wake_up_klogd_work) = {
@ kernel/printk/printk.c:3079 @ void wake_up_klogd(void)
 	preempt_enable();
 }
 
-void defer_console_output(void)
-{
-	if (!printk_percpu_data_ready())
-		return;
-
-	preempt_disable();
-	__this_cpu_or(printk_pending, PRINTK_PENDING_OUTPUT);
-	irq_work_queue(this_cpu_ptr(&wake_up_klogd_work));
-	preempt_enable();
-}
-
-int vprintk_deferred(const char *fmt, va_list args)
+__printf(1, 0)
+static int vprintk_deferred(const char *fmt, va_list args)
 {
-	int r;
-
-	r = vprintk_emit(0, LOGLEVEL_SCHED, NULL, fmt, args);
-	defer_console_output();
-
-	return r;
+	return vprintk_emit(0, LOGLEVEL_DEFAULT, NULL, fmt, args);
 }
 
 int printk_deferred(const char *fmt, ...)
@ kernel/printk/printk.c:3221 @ EXPORT_SYMBOL_GPL(kmsg_dump_reason_str);
  */
 void kmsg_dump(enum kmsg_dump_reason reason)
 {
+	struct kmsg_dumper_iter iter;
 	struct kmsg_dumper *dumper;
-	unsigned long flags;
+
+	if (!oops_in_progress) {
+		/*
+		 * If atomic consoles are available, activate kernel sync mode
+		 * to make sure any final messages are visible. The trailing
+		 * printk message is important to flush any pending messages.
+		 */
+		if (have_atomic_console()) {
+			sync_mode = true;
+			pr_info("enabled sync mode\n");
+		}
+
+		/*
+		 * Give the printing threads time to flush, allowing up to
+		 * 1s of no printing forward progress before giving up.
+		 */
+		pr_flush(1000, true);
+	}
 
 	rcu_read_lock();
 	list_for_each_entry_rcu(dumper, &dump_list, list) {
@ kernel/printk/printk.c:3258 @ void kmsg_dump(enum kmsg_dump_reason reason)
 			continue;
 
 		/* initialize iterator with data about the stored records */
-		dumper->active = true;
-
-		logbuf_lock_irqsave(flags);
-		dumper->cur_seq = clear_seq;
-		dumper->next_seq = prb_next_seq(prb);
-		logbuf_unlock_irqrestore(flags);
+		iter.active = true;
+		kmsg_dump_rewind(&iter);
 
 		/* invoke dumper which will iterate over records */
-		dumper->dump(dumper, reason);
-
-		/* reset iterator */
-		dumper->active = false;
+		dumper->dump(dumper, reason, &iter);
 	}
 	rcu_read_unlock();
 }
 
 /**
- * kmsg_dump_get_line_nolock - retrieve one kmsg log line (unlocked version)
- * @dumper: registered kmsg dumper
+ * kmsg_dump_get_line - retrieve one kmsg log line
+ * @iter: kmsg dumper iterator
  * @syslog: include the "<4>" prefixes
  * @line: buffer to copy the line to
  * @size: maximum size of the buffer
@ kernel/printk/printk.c:3283 @ void kmsg_dump(enum kmsg_dump_reason reason)
  *
  * A return value of FALSE indicates that there are no more records to
  * read.
- *
- * The function is similar to kmsg_dump_get_line(), but grabs no locks.
  */
-bool kmsg_dump_get_line_nolock(struct kmsg_dumper *dumper, bool syslog,
-			       char *line, size_t size, size_t *len)
+bool kmsg_dump_get_line(struct kmsg_dumper_iter *iter, bool syslog,
+			char *line, size_t size, size_t *len)
 {
 	struct printk_info info;
 	unsigned int line_count;
@ kernel/printk/printk.c:3295 @ bool kmsg_dump_get_line_nolock(struct kmsg_dumper *dumper, bool syslog,
 
 	prb_rec_init_rd(&r, &info, line, size);
 
-	if (!dumper->active)
+	if (!iter->active)
 		goto out;
 
 	/* Read text or count text lines? */
 	if (line) {
-		if (!prb_read_valid(prb, dumper->cur_seq, &r))
+		if (!prb_read_valid(prb, iter->cur_seq, &r))
 			goto out;
 		l = record_print_text(&r, syslog, printk_time);
 	} else {
-		if (!prb_read_valid_info(prb, dumper->cur_seq,
+		if (!prb_read_valid_info(prb, iter->cur_seq,
 					 &info, &line_count)) {
 			goto out;
 		}
@ kernel/printk/printk.c:3313 @ bool kmsg_dump_get_line_nolock(struct kmsg_dumper *dumper, bool syslog,
 
 	}
 
-	dumper->cur_seq = r.info->seq + 1;
+	iter->cur_seq = r.info->seq + 1;
 	ret = true;
 out:
 	if (len)
 		*len = l;
 	return ret;
 }
-
-/**
- * kmsg_dump_get_line - retrieve one kmsg log line
- * @dumper: registered kmsg dumper
- * @syslog: include the "<4>" prefixes
- * @line: buffer to copy the line to
- * @size: maximum size of the buffer
- * @len: length of line placed into buffer
- *
- * Start at the beginning of the kmsg buffer, with the oldest kmsg
- * record, and copy one record into the provided buffer.
- *
- * Consecutive calls will return the next available record moving
- * towards the end of the buffer with the youngest messages.
- *
- * A return value of FALSE indicates that there are no more records to
- * read.
- */
-bool kmsg_dump_get_line(struct kmsg_dumper *dumper, bool syslog,
-			char *line, size_t size, size_t *len)
-{
-	unsigned long flags;
-	bool ret;
-
-	logbuf_lock_irqsave(flags);
-	ret = kmsg_dump_get_line_nolock(dumper, syslog, line, size, len);
-	logbuf_unlock_irqrestore(flags);
-
-	return ret;
-}
 EXPORT_SYMBOL_GPL(kmsg_dump_get_line);
 
 /**
  * kmsg_dump_get_buffer - copy kmsg log lines
- * @dumper: registered kmsg dumper
+ * @iter: kmsg dumper iterator
  * @syslog: include the "<4>" prefixes
  * @buf: buffer to copy the line to
  * @size: maximum size of the buffer
@ kernel/printk/printk.c:3341 @ EXPORT_SYMBOL_GPL(kmsg_dump_get_line);
  * A return value of FALSE indicates that there are no more records to
  * read.
  */
-bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog,
-			  char *buf, size_t size, size_t *len)
+bool kmsg_dump_get_buffer(struct kmsg_dumper_iter *iter, bool syslog,
+			  char *buf, size_t size, size_t *len_out)
 {
 	struct printk_info info;
-	unsigned int line_count;
 	struct printk_record r;
-	unsigned long flags;
 	u64 seq;
 	u64 next_seq;
-	size_t l = 0;
+	size_t len = 0;
 	bool ret = false;
 	bool time = printk_time;
 
-	prb_rec_init_rd(&r, &info, buf, size);
-
-	if (!dumper->active || !buf || !size)
+	if (!iter->active || !buf || !size)
 		goto out;
 
-	logbuf_lock_irqsave(flags);
-	if (prb_read_valid_info(prb, dumper->cur_seq, &info, NULL)) {
-		if (info.seq != dumper->cur_seq) {
+	if (prb_read_valid_info(prb, iter->cur_seq, &info, NULL)) {
+		if (info.seq != iter->cur_seq) {
 			/* messages are gone, move to first available one */
-			dumper->cur_seq = info.seq;
+			iter->cur_seq = info.seq;
 		}
 	}
 
 	/* last entry */
-	if (dumper->cur_seq >= dumper->next_seq) {
-		logbuf_unlock_irqrestore(flags);
+	if (iter->cur_seq >= iter->next_seq)
 		goto out;
-	}
-
-	/* calculate length of entire buffer */
-	seq = dumper->cur_seq;
-	while (prb_read_valid_info(prb, seq, &info, &line_count)) {
-		if (r.info->seq >= dumper->next_seq)
-			break;
-		l += get_record_print_text_size(&info, line_count, syslog, time);
-		seq = r.info->seq + 1;
-	}
 
-	/* move first record forward until length fits into the buffer */
-	seq = dumper->cur_seq;
-	while (l >= size && prb_read_valid_info(prb, seq,
-						&info, &line_count)) {
-		if (r.info->seq >= dumper->next_seq)
-			break;
-		l -= get_record_print_text_size(&info, line_count, syslog, time);
-		seq = r.info->seq + 1;
-	}
+	/*
+	 * Find first record that fits, including all following records,
+	 * into the user-provided buffer for this dump. Pass in size-1
+	 * because this function (by way of record_print_text()) will
+	 * not write more than size-1 bytes of text into @buf.
+	 */
+	seq = find_first_fitting_seq(iter->cur_seq, iter->next_seq,
+				     size - 1, syslog, time);
 
-	/* last message in next interation */
+	/*
+	 * Next kmsg_dump_get_buffer() invocation will dump block of
+	 * older records stored right before this one.
+	 */
 	next_seq = seq;
 
-	/* actually read text into the buffer now */
-	l = 0;
-	while (prb_read_valid(prb, seq, &r)) {
-		if (r.info->seq >= dumper->next_seq)
-			break;
+	prb_rec_init_rd(&r, &info, buf, size);
 
-		l += record_print_text(&r, syslog, time);
+	len = 0;
+	prb_for_each_record(seq, prb, seq, &r) {
+		if (r.info->seq >= iter->next_seq)
+			break;
 
-		/* adjust record to store to remaining buffer space */
-		prb_rec_init_rd(&r, &info, buf + l, size - l);
+		len += record_print_text(&r, syslog, time);
 
-		seq = r.info->seq + 1;
+		/* Adjust record to store to remaining buffer space. */
+		prb_rec_init_rd(&r, &info, buf + len, size - len);
 	}
 
-	dumper->next_seq = next_seq;
+	iter->next_seq = next_seq;
 	ret = true;
-	logbuf_unlock_irqrestore(flags);
 out:
-	if (len)
-		*len = l;
+	if (len_out)
+		*len_out = len;
 	return ret;
 }
 EXPORT_SYMBOL_GPL(kmsg_dump_get_buffer);
 
 /**
- * kmsg_dump_rewind_nolock - reset the iterator (unlocked version)
- * @dumper: registered kmsg dumper
+ * kmsg_dump_rewind - reset the iterator
+ * @iter: kmsg dumper iterator
  *
  * Reset the dumper's iterator so that kmsg_dump_get_line() and
  * kmsg_dump_get_buffer() can be called again and used multiple
  * times within the same dumper.dump() callback.
+ */
+void kmsg_dump_rewind(struct kmsg_dumper_iter *iter)
+{
+	iter->cur_seq = latched_seq_read_nolock(&clear_seq);
+	iter->next_seq = prb_next_seq(prb);
+}
+EXPORT_SYMBOL_GPL(kmsg_dump_rewind);
+
+#endif
+
+struct prb_cpulock {
+	atomic_t owner;
+	unsigned long __percpu *irqflags;
+};
+
+#define DECLARE_STATIC_PRINTKRB_CPULOCK(name)				\
+static DEFINE_PER_CPU(unsigned long, _##name##_percpu_irqflags);	\
+static struct prb_cpulock name = {					\
+	.owner = ATOMIC_INIT(-1),					\
+	.irqflags = &_##name##_percpu_irqflags,				\
+}
+
+static bool __prb_trylock(struct prb_cpulock *cpu_lock,
+			  unsigned int *cpu_store)
+{
+	unsigned long *flags;
+	unsigned int cpu;
+
+	cpu = get_cpu();
+
+	*cpu_store = atomic_read(&cpu_lock->owner);
+	/* memory barrier to ensure the current lock owner is visible */
+	smp_rmb();
+	if (*cpu_store == -1) {
+		flags = per_cpu_ptr(cpu_lock->irqflags, cpu);
+		local_irq_save(*flags);
+		if (atomic_try_cmpxchg_acquire(&cpu_lock->owner,
+					       cpu_store, cpu)) {
+			return true;
+		}
+		local_irq_restore(*flags);
+	} else if (*cpu_store == cpu) {
+		return true;
+	}
+
+	put_cpu();
+	return false;
+}
+
+/*
+ * prb_lock: Perform a processor-reentrant spin lock.
+ * @cpu_lock: A pointer to the lock object.
+ * @cpu_store: A "flags" pointer to store lock status information.
+ *
+ * If no processor has the lock, the calling processor takes the lock and
+ * becomes the owner. If the calling processor is already the owner of the
+ * lock, this function succeeds immediately. If lock is locked by another
+ * processor, this function spins until the calling processor becomes the
+ * owner.
+ *
+ * It is safe to call this function from any context and state.
+ */
+static void prb_lock(struct prb_cpulock *cpu_lock, unsigned int *cpu_store)
+{
+	for (;;) {
+		if (__prb_trylock(cpu_lock, cpu_store))
+			break;
+		cpu_relax();
+	}
+}
+
+/*
+ * prb_unlock: Perform a processor-reentrant spin unlock.
+ * @cpu_lock: A pointer to the lock object.
+ * @cpu_store: A "flags" object storing lock status information.
  *
- * The function is similar to kmsg_dump_rewind(), but grabs no locks.
+ * Release the lock. The calling processor must be the owner of the lock.
+ *
+ * It is safe to call this function from any context and state.
  */
-void kmsg_dump_rewind_nolock(struct kmsg_dumper *dumper)
+static void prb_unlock(struct prb_cpulock *cpu_lock, unsigned int cpu_store)
 {
-	dumper->cur_seq = clear_seq;
-	dumper->next_seq = prb_next_seq(prb);
+	unsigned long *flags;
+	unsigned int cpu;
+
+	cpu = atomic_read(&cpu_lock->owner);
+	atomic_set_release(&cpu_lock->owner, cpu_store);
+
+	if (cpu_store == -1) {
+		flags = per_cpu_ptr(cpu_lock->irqflags, cpu);
+		local_irq_restore(*flags);
+	}
+
+	put_cpu();
+}
+
+DECLARE_STATIC_PRINTKRB_CPULOCK(printk_cpulock);
+
+void console_atomic_lock(unsigned int *flags)
+{
+	prb_lock(&printk_cpulock, flags);
+}
+EXPORT_SYMBOL(console_atomic_lock);
+
+void console_atomic_unlock(unsigned int flags)
+{
+	prb_unlock(&printk_cpulock, flags);
+}
+EXPORT_SYMBOL(console_atomic_unlock);
+
+static void pr_msleep(bool may_sleep, int ms)
+{
+	if (may_sleep) {
+		msleep(ms);
+	} else {
+		while (ms--)
+			udelay(1000);
+	}
 }
 
 /**
- * kmsg_dump_rewind - reset the iterator
- * @dumper: registered kmsg dumper
+ * pr_flush() - Wait for printing threads to catch up.
  *
- * Reset the dumper's iterator so that kmsg_dump_get_line() and
- * kmsg_dump_get_buffer() can be called again and used multiple
- * times within the same dumper.dump() callback.
+ * @timeout_ms:        The maximum time (in ms) to wait.
+ * @reset_on_progress: Reset the timeout if forward progress is seen.
+ *
+ * A value of 0 for @timeout_ms means no waiting will occur. A value of -1
+ * represents infinite waiting.
+ *
+ * If @reset_on_progress is true, the timeout will be reset whenever any
+ * printer has been seen to make some forward progress.
+ *
+ * Context: Any context.
+ * Return: true if all enabled printers are caught up.
  */
-void kmsg_dump_rewind(struct kmsg_dumper *dumper)
+bool pr_flush(int timeout_ms, bool reset_on_progress)
 {
-	unsigned long flags;
+	int remaining = timeout_ms;
+	struct console *con;
+	u64 last_diff = 0;
+	bool may_sleep;
+	u64 printk_seq;
+	u64 diff;
+	u64 seq;
 
-	logbuf_lock_irqsave(flags);
-	kmsg_dump_rewind_nolock(dumper);
-	logbuf_unlock_irqrestore(flags);
-}
-EXPORT_SYMBOL_GPL(kmsg_dump_rewind);
+	may_sleep = (preemptible() &&
+		     !in_softirq() &&
+		     system_state >= SYSTEM_RUNNING);
 
-#endif
+	seq = prb_next_seq(prb);
+
+	for (;;) {
+		diff = 0;
+
+		for_each_console(con) {
+			if (!(con->flags & CON_ENABLED))
+				continue;
+			printk_seq = atomic64_read(&con->printk_seq);
+			if (printk_seq < seq)
+				diff += seq - printk_seq;
+		}
+
+		if (diff != last_diff && reset_on_progress)
+			remaining = timeout_ms;
+
+		if (!diff || remaining == 0)
+			break;
+
+		if (remaining < 0) {
+			pr_msleep(may_sleep, 100);
+		} else if (remaining < 100) {
+			pr_msleep(may_sleep, remaining);
+			remaining = 0;
+		} else {
+			pr_msleep(may_sleep, 100);
+			remaining -= 100;
+		}
+
+		last_diff = diff;
+	}
+
+	return (diff == 0);
+}
+EXPORT_SYMBOL(pr_flush);
@ kernel/printk/printk_safe.c:1 @
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * printk_safe.c - Safe printk for printk-deadlock-prone contexts
- */
-
-#include <linux/preempt.h>
-#include <linux/spinlock.h>
-#include <linux/debug_locks.h>
-#include <linux/kdb.h>
-#include <linux/smp.h>
-#include <linux/cpumask.h>
-#include <linux/irq_work.h>
-#include <linux/printk.h>
-#include <linux/kprobes.h>
-
-#include "internal.h"
-
-/*
- * printk() could not take logbuf_lock in NMI context. Instead,
- * it uses an alternative implementation that temporary stores
- * the strings into a per-CPU buffer. The content of the buffer
- * is later flushed into the main ring buffer via IRQ work.
- *
- * The alternative implementation is chosen transparently
- * by examining current printk() context mask stored in @printk_context
- * per-CPU variable.
- *
- * The implementation allows to flush the strings also from another CPU.
- * There are situations when we want to make sure that all buffers
- * were handled or when IRQs are blocked.
- */
-
-#define SAFE_LOG_BUF_LEN ((1 << CONFIG_PRINTK_SAFE_LOG_BUF_SHIFT) -	\
-				sizeof(atomic_t) -			\
-				sizeof(atomic_t) -			\
-				sizeof(struct irq_work))
-
-struct printk_safe_seq_buf {
-	atomic_t		len;	/* length of written data */
-	atomic_t		message_lost;
-	struct irq_work		work;	/* IRQ work that flushes the buffer */
-	unsigned char		buffer[SAFE_LOG_BUF_LEN];
-};
-
-static DEFINE_PER_CPU(struct printk_safe_seq_buf, safe_print_seq);
-static DEFINE_PER_CPU(int, printk_context);
-
-static DEFINE_RAW_SPINLOCK(safe_read_lock);
-
-#ifdef CONFIG_PRINTK_NMI
-static DEFINE_PER_CPU(struct printk_safe_seq_buf, nmi_print_seq);
-#endif
-
-/* Get flushed in a more safe context. */
-static void queue_flush_work(struct printk_safe_seq_buf *s)
-{
-	if (printk_percpu_data_ready())
-		irq_work_queue(&s->work);
-}
-
-/*
- * Add a message to per-CPU context-dependent buffer. NMI and printk-safe
- * have dedicated buffers, because otherwise printk-safe preempted by
- * NMI-printk would have overwritten the NMI messages.
- *
- * The messages are flushed from irq work (or from panic()), possibly,
- * from other CPU, concurrently with printk_safe_log_store(). Should this
- * happen, printk_safe_log_store() will notice the buffer->len mismatch
- * and repeat the write.
- */
-static __printf(2, 0) int printk_safe_log_store(struct printk_safe_seq_buf *s,
-						const char *fmt, va_list args)
-{
-	int add;
-	size_t len;
-	va_list ap;
-
-again:
-	len = atomic_read(&s->len);
-
-	/* The trailing '\0' is not counted into len. */
-	if (len >= sizeof(s->buffer) - 1) {
-		atomic_inc(&s->message_lost);
-		queue_flush_work(s);
-		return 0;
-	}
-
-	/*
-	 * Make sure that all old data have been read before the buffer
-	 * was reset. This is not needed when we just append data.
-	 */
-	if (!len)
-		smp_rmb();
-
-	va_copy(ap, args);
-	add = vscnprintf(s->buffer + len, sizeof(s->buffer) - len, fmt, ap);
-	va_end(ap);
-	if (!add)
-		return 0;
-
-	/*
-	 * Do it once again if the buffer has been flushed in the meantime.
-	 * Note that atomic_cmpxchg() is an implicit memory barrier that
-	 * makes sure that the data were written before updating s->len.
-	 */
-	if (atomic_cmpxchg(&s->len, len, len + add) != len)
-		goto again;
-
-	queue_flush_work(s);
-	return add;
-}
-
-static inline void printk_safe_flush_line(const char *text, int len)
-{
-	/*
-	 * Avoid any console drivers calls from here, because we may be
-	 * in NMI or printk_safe context (when in panic). The messages
-	 * must go only into the ring buffer at this stage.  Consoles will
-	 * get explicitly called later when a crashdump is not generated.
-	 */
-	printk_deferred("%.*s", len, text);
-}
-
-/* printk part of the temporary buffer line by line */
-static int printk_safe_flush_buffer(const char *start, size_t len)
-{
-	const char *c, *end;
-	bool header;
-
-	c = start;
-	end = start + len;
-	header = true;
-
-	/* Print line by line. */
-	while (c < end) {
-		if (*c == '\n') {
-			printk_safe_flush_line(start, c - start + 1);
-			start = ++c;
-			header = true;
-			continue;
-		}
-
-		/* Handle continuous lines or missing new line. */
-		if ((c + 1 < end) && printk_get_level(c)) {
-			if (header) {
-				c = printk_skip_level(c);
-				continue;
-			}
-
-			printk_safe_flush_line(start, c - start);
-			start = c++;
-			header = true;
-			continue;
-		}
-
-		header = false;
-		c++;
-	}
-
-	/* Check if there was a partial line. Ignore pure header. */
-	if (start < end && !header) {
-		static const char newline[] = KERN_CONT "\n";
-
-		printk_safe_flush_line(start, end - start);
-		printk_safe_flush_line(newline, strlen(newline));
-	}
-
-	return len;
-}
-
-static void report_message_lost(struct printk_safe_seq_buf *s)
-{
-	int lost = atomic_xchg(&s->message_lost, 0);
-
-	if (lost)
-		printk_deferred("Lost %d message(s)!\n", lost);
-}
-
-/*
- * Flush data from the associated per-CPU buffer. The function
- * can be called either via IRQ work or independently.
- */
-static void __printk_safe_flush(struct irq_work *work)
-{
-	struct printk_safe_seq_buf *s =
-		container_of(work, struct printk_safe_seq_buf, work);
-	unsigned long flags;
-	size_t len;
-	int i;
-
-	/*
-	 * The lock has two functions. First, one reader has to flush all
-	 * available message to make the lockless synchronization with
-	 * writers easier. Second, we do not want to mix messages from
-	 * different CPUs. This is especially important when printing
-	 * a backtrace.
-	 */
-	raw_spin_lock_irqsave(&safe_read_lock, flags);
-
-	i = 0;
-more:
-	len = atomic_read(&s->len);
-
-	/*
-	 * This is just a paranoid check that nobody has manipulated
-	 * the buffer an unexpected way. If we printed something then
-	 * @len must only increase. Also it should never overflow the
-	 * buffer size.
-	 */
-	if ((i && i >= len) || len > sizeof(s->buffer)) {
-		const char *msg = "printk_safe_flush: internal error\n";
-
-		printk_safe_flush_line(msg, strlen(msg));
-		len = 0;
-	}
-
-	if (!len)
-		goto out; /* Someone else has already flushed the buffer. */
-
-	/* Make sure that data has been written up to the @len */
-	smp_rmb();
-	i += printk_safe_flush_buffer(s->buffer + i, len - i);
-
-	/*
-	 * Check that nothing has got added in the meantime and truncate
-	 * the buffer. Note that atomic_cmpxchg() is an implicit memory
-	 * barrier that makes sure that the data were copied before
-	 * updating s->len.
-	 */
-	if (atomic_cmpxchg(&s->len, len, 0) != len)
-		goto more;
-
-out:
-	report_message_lost(s);
-	raw_spin_unlock_irqrestore(&safe_read_lock, flags);
-}
-
-/**
- * printk_safe_flush - flush all per-cpu nmi buffers.
- *
- * The buffers are flushed automatically via IRQ work. This function
- * is useful only when someone wants to be sure that all buffers have
- * been flushed at some point.
- */
-void printk_safe_flush(void)
-{
-	int cpu;
-
-	for_each_possible_cpu(cpu) {
-#ifdef CONFIG_PRINTK_NMI
-		__printk_safe_flush(&per_cpu(nmi_print_seq, cpu).work);
-#endif
-		__printk_safe_flush(&per_cpu(safe_print_seq, cpu).work);
-	}
-}
-
-/**
- * printk_safe_flush_on_panic - flush all per-cpu nmi buffers when the system
- *	goes down.
- *
- * Similar to printk_safe_flush() but it can be called even in NMI context when
- * the system goes down. It does the best effort to get NMI messages into
- * the main ring buffer.
- *
- * Note that it could try harder when there is only one CPU online.
- */
-void printk_safe_flush_on_panic(void)
-{
-	/*
-	 * Make sure that we could access the main ring buffer.
-	 * Do not risk a double release when more CPUs are up.
-	 */
-	if (raw_spin_is_locked(&logbuf_lock)) {
-		if (num_online_cpus() > 1)
-			return;
-
-		debug_locks_off();
-		raw_spin_lock_init(&logbuf_lock);
-	}
-
-	if (raw_spin_is_locked(&safe_read_lock)) {
-		if (num_online_cpus() > 1)
-			return;
-
-		debug_locks_off();
-		raw_spin_lock_init(&safe_read_lock);
-	}
-
-	printk_safe_flush();
-}
-
-#ifdef CONFIG_PRINTK_NMI
-/*
- * Safe printk() for NMI context. It uses a per-CPU buffer to
- * store the message. NMIs are not nested, so there is always only
- * one writer running. But the buffer might get flushed from another
- * CPU, so we need to be careful.
- */
-static __printf(1, 0) int vprintk_nmi(const char *fmt, va_list args)
-{
-	struct printk_safe_seq_buf *s = this_cpu_ptr(&nmi_print_seq);
-
-	return printk_safe_log_store(s, fmt, args);
-}
-
-void noinstr printk_nmi_enter(void)
-{
-	this_cpu_add(printk_context, PRINTK_NMI_CONTEXT_OFFSET);
-}
-
-void noinstr printk_nmi_exit(void)
-{
-	this_cpu_sub(printk_context, PRINTK_NMI_CONTEXT_OFFSET);
-}
-
-/*
- * Marks a code that might produce many messages in NMI context
- * and the risk of losing them is more critical than eventual
- * reordering.
- *
- * It has effect only when called in NMI context. Then printk()
- * will try to store the messages into the main logbuf directly
- * and use the per-CPU buffers only as a fallback when the lock
- * is not available.
- */
-void printk_nmi_direct_enter(void)
-{
-	if (this_cpu_read(printk_context) & PRINTK_NMI_CONTEXT_MASK)
-		this_cpu_or(printk_context, PRINTK_NMI_DIRECT_CONTEXT_MASK);
-}
-
-void printk_nmi_direct_exit(void)
-{
-	this_cpu_and(printk_context, ~PRINTK_NMI_DIRECT_CONTEXT_MASK);
-}
-
-#else
-
-static __printf(1, 0) int vprintk_nmi(const char *fmt, va_list args)
-{
-	return 0;
-}
-
-#endif /* CONFIG_PRINTK_NMI */
-
-/*
- * Lock-less printk(), to avoid deadlocks should the printk() recurse
- * into itself. It uses a per-CPU buffer to store the message, just like
- * NMI.
- */
-static __printf(1, 0) int vprintk_safe(const char *fmt, va_list args)
-{
-	struct printk_safe_seq_buf *s = this_cpu_ptr(&safe_print_seq);
-
-	return printk_safe_log_store(s, fmt, args);
-}
-
-/* Can be preempted by NMI. */
-void __printk_safe_enter(void)
-{
-	this_cpu_inc(printk_context);
-}
-
-/* Can be preempted by NMI. */
-void __printk_safe_exit(void)
-{
-	this_cpu_dec(printk_context);
-}
-
-__printf(1, 0) int vprintk_func(const char *fmt, va_list args)
-{
-#ifdef CONFIG_KGDB_KDB
-	/* Allow to pass printk() to kdb but avoid a recursion. */
-	if (unlikely(kdb_trap_printk && kdb_printf_cpu < 0))
-		return vkdb_printf(KDB_MSGSRC_PRINTK, fmt, args);
-#endif
-
-	/*
-	 * Try to use the main logbuf even in NMI. But avoid calling console
-	 * drivers that might have their own locks.
-	 */
-	if ((this_cpu_read(printk_context) & PRINTK_NMI_DIRECT_CONTEXT_MASK) &&
-	    raw_spin_trylock(&logbuf_lock)) {
-		int len;
-
-		len = vprintk_store(0, LOGLEVEL_DEFAULT, NULL, fmt, args);
-		raw_spin_unlock(&logbuf_lock);
-		defer_console_output();
-		return len;
-	}
-
-	/* Use extra buffer in NMI when logbuf_lock is taken or in safe mode. */
-	if (this_cpu_read(printk_context) & PRINTK_NMI_CONTEXT_MASK)
-		return vprintk_nmi(fmt, args);
-
-	/* Use extra buffer to prevent a recursion deadlock in safe mode. */
-	if (this_cpu_read(printk_context) & PRINTK_SAFE_CONTEXT_MASK)
-		return vprintk_safe(fmt, args);
-
-	/* No obstacles. */
-	return vprintk_default(fmt, args);
-}
-
-void __init printk_safe_init(void)
-{
-	int cpu;
-
-	for_each_possible_cpu(cpu) {
-		struct printk_safe_seq_buf *s;
-
-		s = &per_cpu(safe_print_seq, cpu);
-		init_irq_work(&s->work, __printk_safe_flush);
-
-#ifdef CONFIG_PRINTK_NMI
-		s = &per_cpu(nmi_print_seq, cpu);
-		init_irq_work(&s->work, __printk_safe_flush);
-#endif
-	}
-
-	/* Flush pending messages that did not have scheduled IRQ works. */
-	printk_safe_flush();
-}
@ kernel/ptrace.c:199 @ static bool ptrace_freeze_traced(struct task_struct *task)
 	spin_lock_irq(&task->sighand->siglock);
 	if (task_is_traced(task) && !looks_like_a_spurious_pid(task) &&
 	    !__fatal_signal_pending(task)) {
-		task->state = __TASK_TRACED;
+		unsigned long flags;
+
+		raw_spin_lock_irqsave(&task->pi_lock, flags);
+		if (task->state & __TASK_TRACED)
+			task->state = __TASK_TRACED;
+		else
+			task->saved_state = __TASK_TRACED;
+		raw_spin_unlock_irqrestore(&task->pi_lock, flags);
 		ret = true;
 	}
 	spin_unlock_irq(&task->sighand->siglock);
@ kernel/ptrace.c:216 @ static bool ptrace_freeze_traced(struct task_struct *task)
 
 static void ptrace_unfreeze_traced(struct task_struct *task)
 {
-	if (task->state != __TASK_TRACED)
-		return;
+	unsigned long flags;
+	bool frozen = true;
 
 	WARN_ON(!task->ptrace || task->parent != current);
 
@ kernel/ptrace.c:226 @ static void ptrace_unfreeze_traced(struct task_struct *task)
 	 * Recheck state under the lock to close this race.
 	 */
 	spin_lock_irq(&task->sighand->siglock);
-	if (task->state == __TASK_TRACED) {
-		if (__fatal_signal_pending(task))
-			wake_up_state(task, __TASK_TRACED);
-		else
-			task->state = TASK_TRACED;
-	}
+
+	raw_spin_lock_irqsave(&task->pi_lock, flags);
+	if (task->state == __TASK_TRACED)
+		task->state = TASK_TRACED;
+	else if (task->saved_state == __TASK_TRACED)
+		task->saved_state = TASK_TRACED;
+	else
+		frozen = false;
+	raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+
+	if (frozen && __fatal_signal_pending(task))
+		wake_up_state(task, __TASK_TRACED);
+
 	spin_unlock_irq(&task->sighand->siglock);
 }
 
@ kernel/rcu/Kconfig:191 @ config RCU_FAST_NO_HZ
 
 config RCU_BOOST
 	bool "Enable RCU priority boosting"
-	depends on RT_MUTEXES && PREEMPT_RCU && RCU_EXPERT
-	default n
+	depends on (RT_MUTEXES && PREEMPT_RCU && RCU_EXPERT) || PREEMPT_RT
+	default y if PREEMPT_RT
 	help
 	  This option boosts the priority of preempted RCU readers that
 	  block the current preemptible RCU grace period for too long.
@ kernel/rcu/tree.c:103 @ static struct rcu_state rcu_state = {
 static bool dump_tree;
 module_param(dump_tree, bool, 0444);
 /* By default, use RCU_SOFTIRQ instead of rcuc kthreads. */
-static bool use_softirq = true;
+static bool use_softirq = !IS_ENABLED(CONFIG_PREEMPT_RT);
+#ifndef CONFIG_PREEMPT_RT
 module_param(use_softirq, bool, 0444);
+#endif
 /* Control rcu_node-tree auto-balancing at boot time. */
 static bool rcu_fanout_exact;
 module_param(rcu_fanout_exact, bool, 0444);
@ kernel/rcu/update.c:59 @
 #ifndef CONFIG_TINY_RCU
 module_param(rcu_expedited, int, 0);
 module_param(rcu_normal, int, 0);
-static int rcu_normal_after_boot;
+static int rcu_normal_after_boot = IS_ENABLED(CONFIG_PREEMPT_RT);
+#ifndef CONFIG_PREEMPT_RT
 module_param(rcu_normal_after_boot, int, 0);
+#endif
 #endif /* #ifndef CONFIG_TINY_RCU */
 
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
@ kernel/sched/core.c:67 @ const_debug unsigned int sysctl_sched_features =
  * Number of tasks to iterate in a single balance run.
  * Limited because this is done with IRQs disabled.
  */
+#ifdef CONFIG_PREEMPT_RT
+const_debug unsigned int sysctl_sched_nr_migrate = 8;
+#else
 const_debug unsigned int sysctl_sched_nr_migrate = 32;
+#endif
 
 /*
  * period over which we measure -rt task CPU usage in us.
@ kernel/sched/core.c:517 @ static bool set_nr_if_polling(struct task_struct *p)
 #endif
 #endif
 
-static bool __wake_q_add(struct wake_q_head *head, struct task_struct *task)
+static bool __wake_q_add(struct wake_q_head *head, struct task_struct *task,
+			 bool sleeper)
 {
-	struct wake_q_node *node = &task->wake_q;
+	struct wake_q_node *node;
+
+	if (sleeper)
+		node = &task->wake_q_sleeper;
+	else
+		node = &task->wake_q;
 
 	/*
 	 * Atomically grab the task, if ->wake_q is !nil already it means
@ kernel/sched/core.c:561 @ static bool __wake_q_add(struct wake_q_head *head, struct task_struct *task)
  */
 void wake_q_add(struct wake_q_head *head, struct task_struct *task)
 {
-	if (__wake_q_add(head, task))
+	if (__wake_q_add(head, task, false))
+		get_task_struct(task);
+}
+
+void wake_q_add_sleeper(struct wake_q_head *head, struct task_struct *task)
+{
+	if (__wake_q_add(head, task, true))
 		get_task_struct(task);
 }
 
@ kernel/sched/core.c:590 @ void wake_q_add(struct wake_q_head *head, struct task_struct *task)
  */
 void wake_q_add_safe(struct wake_q_head *head, struct task_struct *task)
 {
-	if (!__wake_q_add(head, task))
+	if (!__wake_q_add(head, task, false))
 		put_task_struct(task);
 }
 
-void wake_up_q(struct wake_q_head *head)
+void __wake_up_q(struct wake_q_head *head, bool sleeper)
 {
 	struct wake_q_node *node = head->first;
 
 	while (node != WAKE_Q_TAIL) {
 		struct task_struct *task;
 
-		task = container_of(node, struct task_struct, wake_q);
+		if (sleeper)
+			task = container_of(node, struct task_struct, wake_q_sleeper);
+		else
+			task = container_of(node, struct task_struct, wake_q);
+
 		BUG_ON(!task);
 		/* Task can safely be re-inserted now: */
 		node = node->next;
-		task->wake_q.next = NULL;
 
+		if (sleeper)
+			task->wake_q_sleeper.next = NULL;
+		else
+			task->wake_q.next = NULL;
 		/*
 		 * wake_up_process() executes a full barrier, which pairs with
 		 * the queueing in wake_q_add() so as not to miss wakeups.
 		 */
-		wake_up_process(task);
+		if (sleeper)
+			wake_up_lock_sleeper(task);
+		else
+			wake_up_process(task);
+
 		put_task_struct(task);
 	}
 }
@ kernel/sched/core.c:658 @ void resched_curr(struct rq *rq)
 		trace_sched_wake_idle_without_ipi(cpu);
 }
 
+#ifdef CONFIG_PREEMPT_LAZY
+
+static int tsk_is_polling(struct task_struct *p)
+{
+#ifdef TIF_POLLING_NRFLAG
+	return test_tsk_thread_flag(p, TIF_POLLING_NRFLAG);
+#else
+	return 0;
+#endif
+}
+
+void resched_curr_lazy(struct rq *rq)
+{
+	struct task_struct *curr = rq->curr;
+	int cpu;
+
+	if (!sched_feat(PREEMPT_LAZY)) {
+		resched_curr(rq);
+		return;
+	}
+
+	lockdep_assert_held(&rq->lock);
+
+	if (test_tsk_need_resched(curr))
+		return;
+
+	if (test_tsk_need_resched_lazy(curr))
+		return;
+
+	set_tsk_need_resched_lazy(curr);
+
+	cpu = cpu_of(rq);
+	if (cpu == smp_processor_id())
+		return;
+
+	/* NEED_RESCHED_LAZY must be visible before we test polling */
+	smp_mb();
+	if (!tsk_is_polling(curr))
+		smp_send_reschedule(cpu);
+}
+#endif
+
 void resched_cpu(int cpu)
 {
 	struct rq *rq = cpu_rq(cpu);
@ kernel/sched/core.c:1777 @ void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags)
 
 #ifdef CONFIG_SMP
 
+static void
+__do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask, u32 flags);
+
+static int __set_cpus_allowed_ptr(struct task_struct *p,
+				  const struct cpumask *new_mask,
+				  u32 flags);
+
+static void migrate_disable_switch(struct rq *rq, struct task_struct *p)
+{
+	if (likely(!p->migration_disabled))
+		return;
+
+	if (p->cpus_ptr != &p->cpus_mask)
+		return;
+
+	/*
+	 * Violates locking rules! see comment in __do_set_cpus_allowed().
+	 */
+	__do_set_cpus_allowed(p, cpumask_of(rq->cpu), SCA_MIGRATE_DISABLE);
+}
+
+void migrate_disable(void)
+{
+	struct task_struct *p = current;
+
+	if (p->migration_disabled) {
+		p->migration_disabled++;
+		return;
+	}
+
+	trace_sched_migrate_disable_tp(p);
+
+	preempt_disable();
+	this_rq()->nr_pinned++;
+	p->migration_disabled = 1;
+	preempt_lazy_disable();
+	preempt_enable();
+}
+EXPORT_SYMBOL_GPL(migrate_disable);
+
+void migrate_enable(void)
+{
+	struct task_struct *p = current;
+
+	if (p->migration_disabled > 1) {
+		p->migration_disabled--;
+		return;
+	}
+
+	/*
+	 * Ensure stop_task runs either before or after this, and that
+	 * __set_cpus_allowed_ptr(SCA_MIGRATE_ENABLE) doesn't schedule().
+	 */
+	preempt_disable();
+	if (p->cpus_ptr != &p->cpus_mask)
+		__set_cpus_allowed_ptr(p, &p->cpus_mask, SCA_MIGRATE_ENABLE);
+	/*
+	 * Mustn't clear migration_disabled() until cpus_ptr points back at the
+	 * regular cpus_mask, otherwise things that race (eg.
+	 * select_fallback_rq) get confused.
+	 */
+	barrier();
+	p->migration_disabled = 0;
+	this_rq()->nr_pinned--;
+	preempt_lazy_enable();
+	preempt_enable();
+
+	trace_sched_migrate_enable_tp(p);
+}
+EXPORT_SYMBOL_GPL(migrate_enable);
+
+static inline bool rq_has_pinned_tasks(struct rq *rq)
+{
+	return rq->nr_pinned;
+}
+
 /*
  * Per-CPU kthreads are allowed to run on !active && online CPUs, see
  * __set_cpus_allowed_ptr() and select_fallback_rq().
@ kernel/sched/core.c:1862 @ static inline bool is_cpu_allowed(struct task_struct *p, int cpu)
 	if (!cpumask_test_cpu(cpu, p->cpus_ptr))
 		return false;
 
-	if (is_per_cpu_kthread(p))
+	if (is_per_cpu_kthread(p) || is_migration_disabled(p))
 		return cpu_online(cpu);
 
 	return cpu_active(cpu);
@ kernel/sched/core.c:1907 @ static struct rq *move_queued_task(struct rq *rq, struct rq_flags *rf,
 }
 
 struct migration_arg {
-	struct task_struct *task;
-	int dest_cpu;
+	struct task_struct		*task;
+	int				dest_cpu;
+	struct set_affinity_pending	*pending;
+};
+
+/*
+ * @refs: number of wait_for_completion()
+ * @stop_pending: is @stop_work in use
+ */
+struct set_affinity_pending {
+	refcount_t		refs;
+	unsigned int		stop_pending;
+	struct completion	done;
+	struct cpu_stop_work	stop_work;
+	struct migration_arg	arg;
 };
 
 /*
@ kernel/sched/core.c:1954 @ static struct rq *__migrate_task(struct rq *rq, struct rq_flags *rf,
 static int migration_cpu_stop(void *data)
 {
 	struct migration_arg *arg = data;
+	struct set_affinity_pending *pending = arg->pending;
 	struct task_struct *p = arg->task;
 	struct rq *rq = this_rq();
+	bool complete = false;
 	struct rq_flags rf;
 
 	/*
 	 * The original target CPU might have gone down and we might
 	 * be on another CPU but it doesn't matter.
 	 */
-	local_irq_disable();
+	local_irq_save(rf.flags);
 	/*
 	 * We need to explicitly wake pending tasks before running
 	 * __migrate_task() such that we will not miss enforcing cpus_ptr
@ kernel/sched/core.c:1974 @ static int migration_cpu_stop(void *data)
 
 	raw_spin_lock(&p->pi_lock);
 	rq_lock(rq, &rf);
+
 	/*
 	 * If task_rq(p) != rq, it cannot be migrated here, because we're
 	 * holding rq->lock, if p->on_rq == 0 it cannot get enqueued because
 	 * we're holding p->pi_lock.
 	 */
 	if (task_rq(p) == rq) {
+		if (is_migration_disabled(p))
+			goto out;
+
+		if (pending) {
+			if (p->migration_pending == pending)
+				p->migration_pending = NULL;
+			complete = true;
+
+			if (cpumask_test_cpu(task_cpu(p), &p->cpus_mask))
+				goto out;
+		}
+
 		if (task_on_rq_queued(p))
 			rq = __migrate_task(rq, &rf, p, arg->dest_cpu);
 		else
 			p->wake_cpu = arg->dest_cpu;
+
+		/*
+		 * XXX __migrate_task() can fail, at which point we might end
+		 * up running on a dodgy CPU, AFAICT this can only happen
+		 * during CPU hotplug, at which point we'll get pushed out
+		 * anyway, so it's probably not a big deal.
+		 */
+
+	} else if (pending) {
+		/*
+		 * This happens when we get migrated between migrate_enable()'s
+		 * preempt_enable() and scheduling the stopper task. At that
+		 * point we're a regular task again and not current anymore.
+		 *
+		 * A !PREEMPT kernel has a giant hole here, which makes it far
+		 * more likely.
+		 */
+
+		/*
+		 * The task moved before the stopper got to run. We're holding
+		 * ->pi_lock, so the allowed mask is stable - if it got
+		 * somewhere allowed, we're done.
+		 */
+		if (cpumask_test_cpu(task_cpu(p), p->cpus_ptr)) {
+			if (p->migration_pending == pending)
+				p->migration_pending = NULL;
+			complete = true;
+			goto out;
+		}
+
+		/*
+		 * When migrate_enable() hits a rq mis-match we can't reliably
+		 * determine is_migration_disabled() and so have to chase after
+		 * it.
+		 */
+		WARN_ON_ONCE(!pending->stop_pending);
+		task_rq_unlock(rq, p, &rf);
+		stop_one_cpu_nowait(task_cpu(p), migration_cpu_stop,
+				    &pending->arg, &pending->stop_work);
+		return 0;
 	}
-	rq_unlock(rq, &rf);
-	raw_spin_unlock(&p->pi_lock);
+out:
+	if (pending)
+		pending->stop_pending = false;
+	task_rq_unlock(rq, p, &rf);
+
+	if (complete)
+		complete_all(&pending->done);
 
-	local_irq_enable();
+	return 0;
+}
+
+int push_cpu_stop(void *arg)
+{
+	struct rq *lowest_rq = NULL, *rq = this_rq();
+	struct task_struct *p = arg;
+
+	raw_spin_lock_irq(&p->pi_lock);
+	raw_spin_lock(&rq->lock);
+
+	if (task_rq(p) != rq)
+		goto out_unlock;
+
+	if (is_migration_disabled(p)) {
+		p->migration_flags |= MDF_PUSH;
+		goto out_unlock;
+	}
+
+	p->migration_flags &= ~MDF_PUSH;
+
+	if (p->sched_class->find_lock_rq)
+		lowest_rq = p->sched_class->find_lock_rq(p, rq);
+
+	if (!lowest_rq)
+		goto out_unlock;
+
+	// XXX validate p is still the highest prio task
+	if (task_rq(p) == rq) {
+		deactivate_task(rq, p, 0);
+		set_task_cpu(p, lowest_rq->cpu);
+		activate_task(lowest_rq, p, 0);
+		resched_curr(lowest_rq);
+	}
+
+	double_unlock_balance(rq, lowest_rq);
+
+out_unlock:
+	rq->push_busy = false;
+	raw_spin_unlock(&rq->lock);
+	raw_spin_unlock_irq(&p->pi_lock);
+
+	put_task_struct(p);
 	return 0;
 }
 
@ kernel/sched/core.c:2096 @ static int migration_cpu_stop(void *data)
  * sched_class::set_cpus_allowed must do the below, but is not required to
  * actually call this function.
  */
-void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask)
+void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask, u32 flags)
 {
+	if (flags & (SCA_MIGRATE_ENABLE | SCA_MIGRATE_DISABLE)) {
+		p->cpus_ptr = new_mask;
+		return;
+	}
+
 	cpumask_copy(&p->cpus_mask, new_mask);
 	p->nr_cpus_allowed = cpumask_weight(new_mask);
 }
 
-void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
+static void
+__do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask, u32 flags)
 {
 	struct rq *rq = task_rq(p);
 	bool queued, running;
 
-	lockdep_assert_held(&p->pi_lock);
+	/*
+	 * This here violates the locking rules for affinity, since we're only
+	 * supposed to change these variables while holding both rq->lock and
+	 * p->pi_lock.
+	 *
+	 * HOWEVER, it magically works, because ttwu() is the only code that
+	 * accesses these variables under p->pi_lock and only does so after
+	 * smp_cond_load_acquire(&p->on_cpu, !VAL), and we're in __schedule()
+	 * before finish_task().
+	 *
+	 * XXX do further audits, this smells like something putrid.
+	 */
+	if (flags & SCA_MIGRATE_DISABLE)
+		SCHED_WARN_ON(!p->on_cpu);
+	else
+		lockdep_assert_held(&p->pi_lock);
 
 	queued = task_on_rq_queued(p);
 	running = task_current(rq, p);
@ kernel/sched/core.c:2144 @ void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
 	if (running)
 		put_prev_task(rq, p);
 
-	p->sched_class->set_cpus_allowed(p, new_mask);
+	p->sched_class->set_cpus_allowed(p, new_mask, flags);
 
 	if (queued)
 		enqueue_task(rq, p, ENQUEUE_RESTORE | ENQUEUE_NOCLOCK);
@ kernel/sched/core.c:2152 @ void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
 		set_next_task(rq, p);
 }
 
+void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
+{
+	__do_set_cpus_allowed(p, new_mask, 0);
+}
+
+/*
+ * This function is wildly self concurrent; here be dragons.
+ *
+ *
+ * When given a valid mask, __set_cpus_allowed_ptr() must block until the
+ * designated task is enqueued on an allowed CPU. If that task is currently
+ * running, we have to kick it out using the CPU stopper.
+ *
+ * Migrate-Disable comes along and tramples all over our nice sandcastle.
+ * Consider:
+ *
+ *     Initial conditions: P0->cpus_mask = [0, 1]
+ *
+ *     P0@CPU0                  P1
+ *
+ *     migrate_disable();
+ *     <preempted>
+ *                              set_cpus_allowed_ptr(P0, [1]);
+ *
+ * P1 *cannot* return from this set_cpus_allowed_ptr() call until P0 executes
+ * its outermost migrate_enable() (i.e. it exits its Migrate-Disable region).
+ * This means we need the following scheme:
+ *
+ *     P0@CPU0                  P1
+ *
+ *     migrate_disable();
+ *     <preempted>
+ *                              set_cpus_allowed_ptr(P0, [1]);
+ *                                <blocks>
+ *     <resumes>
+ *     migrate_enable();
+ *       __set_cpus_allowed_ptr();
+ *       <wakes local stopper>
+ *                         `--> <woken on migration completion>
+ *
+ * Now the fun stuff: there may be several P1-like tasks, i.e. multiple
+ * concurrent set_cpus_allowed_ptr(P0, [*]) calls. CPU affinity changes of any
+ * task p are serialized by p->pi_lock, which we can leverage: the one that
+ * should come into effect at the end of the Migrate-Disable region is the last
+ * one. This means we only need to track a single cpumask (i.e. p->cpus_mask),
+ * but we still need to properly signal those waiting tasks at the appropriate
+ * moment.
+ *
+ * This is implemented using struct set_affinity_pending. The first
+ * __set_cpus_allowed_ptr() caller within a given Migrate-Disable region will
+ * setup an instance of that struct and install it on the targeted task_struct.
+ * Any and all further callers will reuse that instance. Those then wait for
+ * a completion signaled at the tail of the CPU stopper callback (1), triggered
+ * on the end of the Migrate-Disable region (i.e. outermost migrate_enable()).
+ *
+ *
+ * (1) In the cases covered above. There is one more where the completion is
+ * signaled within affine_move_task() itself: when a subsequent affinity request
+ * cancels the need for an active migration. Consider:
+ *
+ *     Initial conditions: P0->cpus_mask = [0, 1]
+ *
+ *     P0@CPU0            P1                             P2
+ *
+ *     migrate_disable();
+ *     <preempted>
+ *                        set_cpus_allowed_ptr(P0, [1]);
+ *                          <blocks>
+ *                                                       set_cpus_allowed_ptr(P0, [0, 1]);
+ *                                                         <signal completion>
+ *                          <awakes>
+ *
+ * Note that the above is safe vs a concurrent migrate_enable(), as any
+ * pending affinity completion is preceded an uninstallion of
+ * p->migration_pending done with p->pi_lock held.
+ */
+static int affine_move_task(struct rq *rq, struct task_struct *p, struct rq_flags *rf,
+			    int dest_cpu, unsigned int flags)
+{
+	struct set_affinity_pending my_pending = { }, *pending = NULL;
+	bool stop_pending, complete = false;
+
+	/* Can the task run on the task's current CPU? If so, we're done */
+	if (cpumask_test_cpu(task_cpu(p), &p->cpus_mask)) {
+		struct task_struct *push_task = NULL;
+
+		if ((flags & SCA_MIGRATE_ENABLE) &&
+		    (p->migration_flags & MDF_PUSH) && !rq->push_busy) {
+			rq->push_busy = true;
+			push_task = get_task_struct(p);
+		}
+
+		/*
+		 * If there are pending waiters, but no pending stop_work,
+		 * then complete now.
+		 */
+		pending = p->migration_pending;
+		if (pending && !pending->stop_pending) {
+			p->migration_pending = NULL;
+			complete = true;
+		}
+
+		task_rq_unlock(rq, p, rf);
+
+		if (push_task) {
+			stop_one_cpu_nowait(rq->cpu, push_cpu_stop,
+					    p, &rq->push_work);
+		}
+
+		if (complete)
+			complete_all(&pending->done);
+
+		return 0;
+	}
+
+	if (!(flags & SCA_MIGRATE_ENABLE)) {
+		/* serialized by p->pi_lock */
+		if (!p->migration_pending) {
+			/* Install the request */
+			refcount_set(&my_pending.refs, 1);
+			init_completion(&my_pending.done);
+			my_pending.arg = (struct migration_arg) {
+				.task = p,
+				.dest_cpu = dest_cpu,
+				.pending = &my_pending,
+			};
+
+			p->migration_pending = &my_pending;
+		} else {
+			pending = p->migration_pending;
+			refcount_inc(&pending->refs);
+			/*
+			 * Affinity has changed, but we've already installed a
+			 * pending. migration_cpu_stop() *must* see this, else
+			 * we risk a completion of the pending despite having a
+			 * task on a disallowed CPU.
+			 *
+			 * Serialized by p->pi_lock, so this is safe.
+			 */
+			pending->arg.dest_cpu = dest_cpu;
+		}
+	}
+	pending = p->migration_pending;
+	/*
+	 * - !MIGRATE_ENABLE:
+	 *   we'll have installed a pending if there wasn't one already.
+	 *
+	 * - MIGRATE_ENABLE:
+	 *   we're here because the current CPU isn't matching anymore,
+	 *   the only way that can happen is because of a concurrent
+	 *   set_cpus_allowed_ptr() call, which should then still be
+	 *   pending completion.
+	 *
+	 * Either way, we really should have a @pending here.
+	 */
+	if (WARN_ON_ONCE(!pending)) {
+		task_rq_unlock(rq, p, rf);
+		return -EINVAL;
+	}
+
+	if (task_running(rq, p) || p->state == TASK_WAKING) {
+		/*
+		 * MIGRATE_ENABLE gets here because 'p == current', but for
+		 * anything else we cannot do is_migration_disabled(), punt
+		 * and have the stopper function handle it all race-free.
+		 */
+		stop_pending = pending->stop_pending;
+		if (!stop_pending)
+			pending->stop_pending = true;
+
+		if (flags & SCA_MIGRATE_ENABLE)
+			p->migration_flags &= ~MDF_PUSH;
+
+		task_rq_unlock(rq, p, rf);
+
+		if (!stop_pending) {
+			stop_one_cpu_nowait(cpu_of(rq), migration_cpu_stop,
+					    &pending->arg, &pending->stop_work);
+		}
+
+		if (flags & SCA_MIGRATE_ENABLE)
+			return 0;
+	} else {
+
+		if (!is_migration_disabled(p)) {
+			if (task_on_rq_queued(p))
+				rq = move_queued_task(rq, rf, p, dest_cpu);
+
+			if (!pending->stop_pending) {
+				p->migration_pending = NULL;
+				complete = true;
+			}
+		}
+		task_rq_unlock(rq, p, rf);
+
+		if (complete)
+			complete_all(&pending->done);
+	}
+
+	wait_for_completion(&pending->done);
+
+	if (refcount_dec_and_test(&pending->refs))
+		wake_up_var(&pending->refs); /* No UaF, just an address */
+
+	/*
+	 * Block the original owner of &pending until all subsequent callers
+	 * have seen the completion and decremented the refcount
+	 */
+	wait_var_event(&my_pending.refs, !refcount_read(&my_pending.refs));
+
+	/* ARGH */
+	WARN_ON_ONCE(my_pending.stop_pending);
+
+	return 0;
+}
+
 /*
  * Change a given task's CPU affinity. Migrate the thread to a
  * proper CPU and schedule it away if the CPU it's executing on
@ kernel/sched/core.c:2378 @ void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
  * call is not atomic; no spinlocks may be held.
  */
 static int __set_cpus_allowed_ptr(struct task_struct *p,
-				  const struct cpumask *new_mask, bool check)
+				  const struct cpumask *new_mask,
+				  u32 flags)
 {
 	const struct cpumask *cpu_valid_mask = cpu_active_mask;
 	unsigned int dest_cpu;
@ kernel/sched/core.c:2390 @ static int __set_cpus_allowed_ptr(struct task_struct *p,
 	rq = task_rq_lock(p, &rf);
 	update_rq_clock(rq);
 
-	if (p->flags & PF_KTHREAD) {
+	if (p->flags & PF_KTHREAD || is_migration_disabled(p)) {
 		/*
-		 * Kernel threads are allowed on online && !active CPUs
+		 * Kernel threads are allowed on online && !active CPUs.
+		 *
+		 * Specifically, migration_disabled() tasks must not fail the
+		 * cpumask_any_and_distribute() pick below, esp. so on
+		 * SCA_MIGRATE_ENABLE, otherwise we'll not call
+		 * set_cpus_allowed_common() and actually reset p->cpus_ptr.
 		 */
 		cpu_valid_mask = cpu_online_mask;
 	}
@ kernel/sched/core.c:2406 @ static int __set_cpus_allowed_ptr(struct task_struct *p,
 	 * Must re-check here, to close a race against __kthread_bind(),
 	 * sched_setaffinity() is not guaranteed to observe the flag.
 	 */
-	if (check && (p->flags & PF_NO_SETAFFINITY)) {
+	if ((flags & SCA_CHECK) && (p->flags & PF_NO_SETAFFINITY)) {
 		ret = -EINVAL;
 		goto out;
 	}
 
-	if (cpumask_equal(&p->cpus_mask, new_mask))
-		goto out;
+	if (!(flags & SCA_MIGRATE_ENABLE)) {
+		if (cpumask_equal(&p->cpus_mask, new_mask))
+			goto out;
+
+		if (WARN_ON_ONCE(p == current &&
+				 is_migration_disabled(p) &&
+				 !cpumask_test_cpu(task_cpu(p), new_mask))) {
+			ret = -EBUSY;
+			goto out;
+		}
+	}
 
 	/*
 	 * Picking a ~random cpu helps in cases where we are changing affinity
@ kernel/sched/core.c:2434 @ static int __set_cpus_allowed_ptr(struct task_struct *p,
 		goto out;
 	}
 
-	do_set_cpus_allowed(p, new_mask);
+	__do_set_cpus_allowed(p, new_mask, flags);
 
 	if (p->flags & PF_KTHREAD) {
 		/*
@ kernel/sched/core.c:2446 @ static int __set_cpus_allowed_ptr(struct task_struct *p,
 			p->nr_cpus_allowed != 1);
 	}
 
-	/* Can the task run on the task's current CPU? If so, we're done */
-	if (cpumask_test_cpu(task_cpu(p), new_mask))
-		goto out;
+	return affine_move_task(rq, p, &rf, dest_cpu, flags);
 
-	if (task_running(rq, p) || p->state == TASK_WAKING) {
-		struct migration_arg arg = { p, dest_cpu };
-		/* Need help from migration thread: drop lock and wait. */
-		task_rq_unlock(rq, p, &rf);
-		stop_one_cpu(cpu_of(rq), migration_cpu_stop, &arg);
-		return 0;
-	} else if (task_on_rq_queued(p)) {
-		/*
-		 * OK, since we're going to drop the lock immediately
-		 * afterwards anyway.
-		 */
-		rq = move_queued_task(rq, &rf, p, dest_cpu);
-	}
 out:
 	task_rq_unlock(rq, p, &rf);
 
@ kernel/sched/core.c:2456 @ static int __set_cpus_allowed_ptr(struct task_struct *p,
 
 int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
 {
-	return __set_cpus_allowed_ptr(p, new_mask, false);
+	return __set_cpus_allowed_ptr(p, new_mask, 0);
 }
 EXPORT_SYMBOL_GPL(set_cpus_allowed_ptr);
 
@ kernel/sched/core.c:2497 @ void set_task_cpu(struct task_struct *p, unsigned int new_cpu)
 	 * Clearly, migrating tasks to offline CPUs is a fairly daft thing.
 	 */
 	WARN_ON_ONCE(!cpu_online(new_cpu));
+
+	WARN_ON_ONCE(is_migration_disabled(p));
 #endif
 
 	trace_sched_migrate_task(p, new_cpu);
@ kernel/sched/core.c:2631 @ int migrate_swap(struct task_struct *cur, struct task_struct *p,
 }
 #endif /* CONFIG_NUMA_BALANCING */
 
+static bool check_task_state(struct task_struct *p, long match_state)
+{
+	bool match = false;
+
+	raw_spin_lock_irq(&p->pi_lock);
+	if (p->state == match_state || p->saved_state == match_state)
+		match = true;
+	raw_spin_unlock_irq(&p->pi_lock);
+
+	return match;
+}
+
 /*
  * wait_task_inactive - wait for a thread to unschedule.
  *
@ kernel/sched/core.c:2687 @ unsigned long wait_task_inactive(struct task_struct *p, long match_state)
 		 * is actually now running somewhere else!
 		 */
 		while (task_running(rq, p)) {
-			if (match_state && unlikely(p->state != match_state))
+			if (match_state && !check_task_state(p, match_state))
 				return 0;
 			cpu_relax();
 		}
@ kernel/sched/core.c:2702 @ unsigned long wait_task_inactive(struct task_struct *p, long match_state)
 		running = task_running(rq, p);
 		queued = task_on_rq_queued(p);
 		ncsw = 0;
-		if (!match_state || p->state == match_state)
+		if (!match_state || p->state == match_state ||
+		    p->saved_state == match_state)
 			ncsw = p->nvcsw | LONG_MIN; /* sets MSB */
 		task_rq_unlock(rq, p, &rf);
 
@ kernel/sched/core.c:2737 @ unsigned long wait_task_inactive(struct task_struct *p, long match_state)
 			ktime_t to = NSEC_PER_SEC / HZ;
 
 			set_current_state(TASK_UNINTERRUPTIBLE);
-			schedule_hrtimeout(&to, HRTIMER_MODE_REL);
+			schedule_hrtimeout(&to, HRTIMER_MODE_REL_HARD);
 			continue;
 		}
 
@ kernel/sched/core.c:2842 @ static int select_fallback_rq(int cpu, struct task_struct *p)
 			}
 			fallthrough;
 		case possible:
+			/*
+			 * XXX When called from select_task_rq() we only
+			 * hold p->pi_lock and again violate locking order.
+			 *
+			 * More yuck to audit.
+			 */
 			do_set_cpus_allowed(p, cpu_possible_mask);
 			state = fail;
 			break;
@ kernel/sched/core.c:2882 @ int select_task_rq(struct task_struct *p, int cpu, int sd_flags, int wake_flags)
 {
 	lockdep_assert_held(&p->pi_lock);
 
-	if (p->nr_cpus_allowed > 1)
+	if (p->nr_cpus_allowed > 1 && !is_migration_disabled(p))
 		cpu = p->sched_class->select_task_rq(p, cpu, sd_flags, wake_flags);
 	else
 		cpu = cpumask_any(p->cpus_ptr);
@ kernel/sched/core.c:2905 @ int select_task_rq(struct task_struct *p, int cpu, int sd_flags, int wake_flags)
 
 void sched_set_stop_task(int cpu, struct task_struct *stop)
 {
+	static struct lock_class_key stop_pi_lock;
 	struct sched_param param = { .sched_priority = MAX_RT_PRIO - 1 };
 	struct task_struct *old_stop = cpu_rq(cpu)->stop;
 
@ kernel/sched/core.c:2921 @ void sched_set_stop_task(int cpu, struct task_struct *stop)
 		sched_setscheduler_nocheck(stop, SCHED_FIFO, &param);
 
 		stop->sched_class = &stop_sched_class;
+
+		/*
+		 * The PI code calls rt_mutex_setprio() with ->pi_lock held to
+		 * adjust the effective priority of a task. As a result,
+		 * rt_mutex_setprio() can trigger (RT) balancing operations,
+		 * which can then trigger wakeups of the stop thread to push
+		 * around the current task.
+		 *
+		 * The stop task itself will never be part of the PI-chain, it
+		 * never blocks, therefore that ->pi_lock recursion is safe.
+		 * Tell lockdep about this by placing the stop->pi_lock in its
+		 * own class.
+		 */
+		lockdep_set_class(&stop->pi_lock, &stop_pi_lock);
 	}
 
 	cpu_rq(cpu)->stop = stop;
@ kernel/sched/core.c:2948 @ void sched_set_stop_task(int cpu, struct task_struct *stop)
 	}
 }
 
-#else
+#else /* CONFIG_SMP */
 
 static inline int __set_cpus_allowed_ptr(struct task_struct *p,
-					 const struct cpumask *new_mask, bool check)
+					 const struct cpumask *new_mask,
+					 u32 flags)
 {
 	return set_cpus_allowed_ptr(p, new_mask);
 }
 
-#endif /* CONFIG_SMP */
+static inline void migrate_disable_switch(struct rq *rq, struct task_struct *p) { }
+
+static inline bool rq_has_pinned_tasks(struct rq *rq)
+{
+	return false;
+}
+
+#endif /* !CONFIG_SMP */
 
 static void
 ttwu_stat(struct task_struct *p, int cpu, int wake_flags)
@ kernel/sched/core.c:3385 @ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
 	int cpu, success = 0;
 
 	preempt_disable();
-	if (p == current) {
+	if (!IS_ENABLED(CONFIG_PREEMPT_RT) && p == current) {
 		/*
 		 * We're waking current, this means 'p->on_rq' and 'task_cpu(p)
 		 * == smp_processor_id()'. Together this means we can special
@ kernel/sched/core.c:3415 @ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
 	 */
 	raw_spin_lock_irqsave(&p->pi_lock, flags);
 	smp_mb__after_spinlock();
-	if (!(p->state & state))
+	if (!(p->state & state)) {
+		/*
+		 * The task might be running due to a spinlock sleeper
+		 * wakeup. Check the saved state and set it to running
+		 * if the wakeup condition is true.
+		 */
+		if (!(wake_flags & WF_LOCK_SLEEPER)) {
+			if (p->saved_state & state) {
+				p->saved_state = TASK_RUNNING;
+				success = 1;
+			}
+		}
 		goto unlock;
+	}
+	/*
+	 * If this is a regular wakeup, then we can unconditionally
+	 * clear the saved state of a "lock sleeper".
+	 */
+	if (!(wake_flags & WF_LOCK_SLEEPER))
+		p->saved_state = TASK_RUNNING;
 
 	trace_sched_waking(p);
 
@ kernel/sched/core.c:3623 @ int wake_up_process(struct task_struct *p)
 }
 EXPORT_SYMBOL(wake_up_process);
 
+/**
+ * wake_up_lock_sleeper - Wake up a specific process blocked on a "sleeping lock"
+ * @p: The process to be woken up.
+ *
+ * Same as wake_up_process() above, but wake_flags=WF_LOCK_SLEEPER to indicate
+ * the nature of the wakeup.
+ */
+int wake_up_lock_sleeper(struct task_struct *p)
+{
+	return try_to_wake_up(p, TASK_UNINTERRUPTIBLE, WF_LOCK_SLEEPER);
+}
+
 int wake_up_state(struct task_struct *p, unsigned int state)
 {
 	return try_to_wake_up(p, state, 0);
@ kernel/sched/core.c:3688 @ static void __sched_fork(unsigned long clone_flags, struct task_struct *p)
 	init_numa_balancing(clone_flags, p);
 #ifdef CONFIG_SMP
 	p->wake_entry.u_flags = CSD_TYPE_TTWU;
+	p->migration_pending = NULL;
 #endif
 }
 
@ kernel/sched/core.c:3862 @ int sched_fork(unsigned long clone_flags, struct task_struct *p)
 	p->on_cpu = 0;
 #endif
 	init_task_preempt_count(p);
+#ifdef CONFIG_HAVE_PREEMPT_LAZY
+	task_thread_info(p)->preempt_lazy_count = 0;
+#endif
 #ifdef CONFIG_SMP
 	plist_node_init(&p->pushable_tasks, MAX_PRIO);
 	RB_CLEAR_NODE(&p->pushable_dl_tasks);
@ kernel/sched/core.c:4037 @ fire_sched_out_preempt_notifiers(struct task_struct *curr,
 
 #else /* !CONFIG_PREEMPT_NOTIFIERS */
 
-static inline void fire_sched_in_preempt_notifiers(struct task_struct *curr)
+static inline void fire_sched_in_preempt_notifiers(struct task_struct *curr)
+{
+}
+
+static inline void
+fire_sched_out_preempt_notifiers(struct task_struct *curr,
+				 struct task_struct *next)
+{
+}
+
+#endif /* CONFIG_PREEMPT_NOTIFIERS */
+
+static inline void prepare_task(struct task_struct *next)
+{
+#ifdef CONFIG_SMP
+	/*
+	 * Claim the task as running, we do this before switching to it
+	 * such that any running task will have this set.
+	 *
+	 * See the ttwu() WF_ON_CPU case and its ordering comment.
+	 */
+	WRITE_ONCE(next->on_cpu, 1);
+#endif
+}
+
+static inline void finish_task(struct task_struct *prev)
+{
+#ifdef CONFIG_SMP
+	/*
+	 * This must be the very last reference to @prev from this CPU. After
+	 * p->on_cpu is cleared, the task can be moved to a different CPU. We
+	 * must ensure this doesn't happen until the switch is completely
+	 * finished.
+	 *
+	 * In particular, the load of prev->state in finish_task_switch() must
+	 * happen before this.
+	 *
+	 * Pairs with the smp_cond_load_acquire() in try_to_wake_up().
+	 */
+	smp_store_release(&prev->on_cpu, 0);
+#endif
+}
+
+#ifdef CONFIG_SMP
+
+static void do_balance_callbacks(struct rq *rq, struct callback_head *head)
+{
+	void (*func)(struct rq *rq);
+	struct callback_head *next;
+
+	lockdep_assert_held(&rq->lock);
+
+	while (head) {
+		func = (void (*)(struct rq *))head->func;
+		next = head->next;
+		head->next = NULL;
+		head = next;
+
+		func(rq);
+	}
+}
+
+static inline struct callback_head *splice_balance_callbacks(struct rq *rq)
+{
+	struct callback_head *head = rq->balance_callback;
+
+	lockdep_assert_held(&rq->lock);
+	if (head) {
+		rq->balance_callback = NULL;
+		rq->balance_flags &= ~BALANCE_WORK;
+	}
+
+	return head;
+}
+
+static void __balance_callbacks(struct rq *rq)
+{
+	do_balance_callbacks(rq, splice_balance_callbacks(rq));
+}
+
+static inline void balance_callbacks(struct rq *rq, struct callback_head *head)
+{
+	unsigned long flags;
+
+	if (unlikely(head)) {
+		raw_spin_lock_irqsave(&rq->lock, flags);
+		do_balance_callbacks(rq, head);
+		raw_spin_unlock_irqrestore(&rq->lock, flags);
+	}
+}
+
+static void balance_push(struct rq *rq);
+
+static inline void balance_switch(struct rq *rq)
+{
+	if (likely(!rq->balance_flags))
+		return;
+
+	if (rq->balance_flags & BALANCE_PUSH) {
+		balance_push(rq);
+		return;
+	}
+
+	__balance_callbacks(rq);
+}
+
+#else
+
+static inline void __balance_callbacks(struct rq *rq)
 {
 }
 
-static inline void
-fire_sched_out_preempt_notifiers(struct task_struct *curr,
-				 struct task_struct *next)
+static inline struct callback_head *splice_balance_callbacks(struct rq *rq)
 {
+	return NULL;
 }
 
-#endif /* CONFIG_PREEMPT_NOTIFIERS */
-
-static inline void prepare_task(struct task_struct *next)
+static inline void balance_callbacks(struct rq *rq, struct callback_head *head)
 {
-#ifdef CONFIG_SMP
-	/*
-	 * Claim the task as running, we do this before switching to it
-	 * such that any running task will have this set.
-	 *
-	 * See the ttwu() WF_ON_CPU case and its ordering comment.
-	 */
-	WRITE_ONCE(next->on_cpu, 1);
-#endif
 }
 
-static inline void finish_task(struct task_struct *prev)
+static inline void balance_switch(struct rq *rq)
 {
-#ifdef CONFIG_SMP
-	/*
-	 * This must be the very last reference to @prev from this CPU. After
-	 * p->on_cpu is cleared, the task can be moved to a different CPU. We
-	 * must ensure this doesn't happen until the switch is completely
-	 * finished.
-	 *
-	 * In particular, the load of prev->state in finish_task_switch() must
-	 * happen before this.
-	 *
-	 * Pairs with the smp_cond_load_acquire() in try_to_wake_up().
-	 */
-	smp_store_release(&prev->on_cpu, 0);
-#endif
 }
 
+#endif
+
 static inline void
 prepare_lock_switch(struct rq *rq, struct task_struct *next, struct rq_flags *rf)
 {
@ kernel/sched/core.c:4189 @ static inline void finish_lock_switch(struct rq *rq)
 	 * prev into current:
 	 */
 	spin_acquire(&rq->lock.dep_map, 0, 0, _THIS_IP_);
+	balance_switch(rq);
 	raw_spin_unlock_irq(&rq->lock);
 }
 
@ kernel/sched/core.c:4205 @ static inline void finish_lock_switch(struct rq *rq)
 # define finish_arch_post_lock_switch()	do { } while (0)
 #endif
 
+static inline void kmap_local_sched_out(void)
+{
+#ifdef CONFIG_KMAP_LOCAL
+	if (unlikely(current->kmap_ctrl.idx))
+		__kmap_local_sched_out();
+#endif
+}
+
+static inline void kmap_local_sched_in(void)
+{
+#ifdef CONFIG_KMAP_LOCAL
+	if (unlikely(current->kmap_ctrl.idx))
+		__kmap_local_sched_in();
+#endif
+}
+
 /**
  * prepare_task_switch - prepare to switch tasks
  * @rq: the runqueue preparing to switch
@ kernel/sched/core.c:4243 @ prepare_task_switch(struct rq *rq, struct task_struct *prev,
 	perf_event_task_sched_out(prev, next);
 	rseq_preempt(prev);
 	fire_sched_out_preempt_notifiers(prev, next);
+	kmap_local_sched_out();
 	prepare_task(next);
 	prepare_arch_switch(next);
 }
@ kernel/sched/core.c:4310 @ static struct rq *finish_task_switch(struct task_struct *prev)
 	finish_lock_switch(rq);
 	finish_arch_post_lock_switch();
 	kcov_finish_switch(current);
+	kmap_local_sched_in();
 
 	fire_sched_in_preempt_notifiers(current);
 	/*
@ kernel/sched/core.c:4325 @ static struct rq *finish_task_switch(struct task_struct *prev)
 	 *   provided by mmdrop(),
 	 * - a sync_core for SYNC_CORE.
 	 */
+	/*
+	 * We use mmdrop_delayed() here so we don't have to do the
+	 * full __mmdrop() when we are the last user.
+	 */
 	if (mm) {
 		membarrier_mm_sync_core_before_usermode(mm);
-		mmdrop(mm);
+		mmdrop_delayed(mm);
 	}
 	if (unlikely(prev_state == TASK_DEAD)) {
 		if (prev->sched_class->task_dead)
 			prev->sched_class->task_dead(prev);
 
-		/*
-		 * Remove function-return probe instances associated with this
-		 * task and put them back on the free list.
-		 */
-		kprobe_flush_task(prev);
-
-		/* Task is done with its stack. */
-		put_task_stack(prev);
-
 		put_task_struct_rcu_user(prev);
 	}
 
@ kernel/sched/core.c:4344 @ static struct rq *finish_task_switch(struct task_struct *prev)
 	return rq;
 }
 
-#ifdef CONFIG_SMP
-
-/* rq->lock is NOT held, but preemption is disabled */
-static void __balance_callback(struct rq *rq)
-{
-	struct callback_head *head, *next;
-	void (*func)(struct rq *rq);
-	unsigned long flags;
-
-	raw_spin_lock_irqsave(&rq->lock, flags);
-	head = rq->balance_callback;
-	rq->balance_callback = NULL;
-	while (head) {
-		func = (void (*)(struct rq *))head->func;
-		next = head->next;
-		head->next = NULL;
-		head = next;
-
-		func(rq);
-	}
-	raw_spin_unlock_irqrestore(&rq->lock, flags);
-}
-
-static inline void balance_callback(struct rq *rq)
-{
-	if (unlikely(rq->balance_callback))
-		__balance_callback(rq);
-}
-
-#else
-
-static inline void balance_callback(struct rq *rq)
-{
-}
-
-#endif
-
 /**
  * schedule_tail - first thing a freshly forked thread must call.
  * @prev: the thread we just switched away from.
@ kernel/sched/core.c:4363 @ asmlinkage __visible void schedule_tail(struct task_struct *prev)
 	 */
 
 	rq = finish_task_switch(prev);
-	balance_callback(rq);
 	preempt_enable();
 
 	if (current->set_child_tid)
@ kernel/sched/core.c:5057 @ pick_next_task(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
  *
  * WARNING: must be called with preemption disabled!
  */
-static void __sched notrace __schedule(bool preempt)
+static void __sched notrace __schedule(bool preempt, bool spinning_lock)
 {
 	struct task_struct *prev, *next;
 	unsigned long *switch_count;
@ kernel/sched/core.c:5110 @ static void __sched notrace __schedule(bool preempt)
 	 *  - ptrace_{,un}freeze_traced() can change ->state underneath us.
 	 */
 	prev_state = prev->state;
-	if (!preempt && prev_state) {
+	if ((!preempt || spinning_lock) && prev_state) {
 		if (signal_pending_state(prev_state, prev)) {
 			prev->state = TASK_RUNNING;
 		} else {
@ kernel/sched/core.c:5145 @ static void __sched notrace __schedule(bool preempt)
 
 	next = pick_next_task(rq, prev, &rf);
 	clear_tsk_need_resched(prev);
+	clear_tsk_need_resched_lazy(prev);
 	clear_preempt_need_resched();
 
 	if (likely(prev != next)) {
@ kernel/sched/core.c:5171 @ static void __sched notrace __schedule(bool preempt)
 		 */
 		++*switch_count;
 
+		migrate_disable_switch(rq, prev);
 		psi_sched_switch(prev, next, !task_on_rq_queued(prev));
 
 		trace_sched_switch(preempt, prev, next);
@ kernel/sched/core.c:5180 @ static void __sched notrace __schedule(bool preempt)
 		rq = context_switch(rq, prev, next, &rf);
 	} else {
 		rq->clock_update_flags &= ~(RQCF_ACT_SKIP|RQCF_REQ_SKIP);
-		rq_unlock_irq(rq, &rf);
-	}
 
-	balance_callback(rq);
+		rq_unpin_lock(rq, &rf);
+		__balance_callbacks(rq);
+		raw_spin_unlock_irq(&rq->lock);
+	}
 }
 
 void __noreturn do_task_dead(void)
@ kernel/sched/core.c:5195 @ void __noreturn do_task_dead(void)
 	/* Tell freezer to ignore us: */
 	current->flags |= PF_NOFREEZE;
 
-	__schedule(false);
+	__schedule(false, false);
 	BUG();
 
 	/* Avoid "noreturn function does return" - but don't continue if BUG() is a NOP: */
@ kernel/sched/core.c:5228 @ static inline void sched_submit_work(struct task_struct *tsk)
 		preempt_enable_no_resched();
 	}
 
-	if (tsk_is_pi_blocked(tsk))
-		return;
-
 	/*
 	 * If we are going to sleep and we have plugged IO queued,
 	 * make sure to submit it to avoid deadlocks.
@ kernel/sched/core.c:5253 @ asmlinkage __visible void __sched schedule(void)
 	sched_submit_work(tsk);
 	do {
 		preempt_disable();
-		__schedule(false);
+		__schedule(false, false);
 		sched_preempt_enable_no_resched();
 	} while (need_resched());
 	sched_update_worker(tsk);
@ kernel/sched/core.c:5281 @ void __sched schedule_idle(void)
 	 */
 	WARN_ON_ONCE(current->state);
 	do {
-		__schedule(false);
+		__schedule(false, false);
 	} while (need_resched());
 }
 
@ kernel/sched/core.c:5334 @ static void __sched notrace preempt_schedule_common(void)
 		 */
 		preempt_disable_notrace();
 		preempt_latency_start(1);
-		__schedule(true);
+		__schedule(true, false);
 		preempt_latency_stop(1);
 		preempt_enable_no_resched_notrace();
 
@ kernel/sched/core.c:5345 @ static void __sched notrace preempt_schedule_common(void)
 	} while (need_resched());
 }
 
+#ifdef CONFIG_PREEMPT_LAZY
+/*
+ * If TIF_NEED_RESCHED is then we allow to be scheduled away since this is
+ * set by a RT task. Oterwise we try to avoid beeing scheduled out as long as
+ * preempt_lazy_count counter >0.
+ */
+static __always_inline int preemptible_lazy(void)
+{
+	if (test_thread_flag(TIF_NEED_RESCHED))
+		return 1;
+	if (current_thread_info()->preempt_lazy_count)
+		return 0;
+	return 1;
+}
+
+#else
+
+static inline int preemptible_lazy(void)
+{
+	return 1;
+}
+
+#endif
+
 #ifdef CONFIG_PREEMPTION
 /*
  * This is the entry point to schedule() from in-kernel preemption
@ kernel/sched/core.c:5382 @ asmlinkage __visible void __sched notrace preempt_schedule(void)
 	 */
 	if (likely(!preemptible()))
 		return;
-
+	if (!preemptible_lazy())
+		return;
 	preempt_schedule_common();
 }
 NOKPROBE_SYMBOL(preempt_schedule);
 EXPORT_SYMBOL(preempt_schedule);
 
+#ifdef CONFIG_PREEMPT_RT
+void __sched notrace preempt_schedule_lock(void)
+{
+	do {
+		preempt_disable();
+		__schedule(true, true);
+		sched_preempt_enable_no_resched();
+	} while (need_resched());
+}
+NOKPROBE_SYMBOL(preempt_schedule_lock);
+EXPORT_SYMBOL(preempt_schedule_lock);
+#endif
+
 /**
  * preempt_schedule_notrace - preempt_schedule called by tracing
  *
@ kernel/sched/core.c:5423 @ asmlinkage __visible void __sched notrace preempt_schedule_notrace(void)
 	if (likely(!preemptible()))
 		return;
 
+	if (!preemptible_lazy())
+		return;
+
 	do {
 		/*
 		 * Because the function tracer can trace preempt_count_sub()
@ kernel/sched/core.c:5448 @ asmlinkage __visible void __sched notrace preempt_schedule_notrace(void)
 		 * an infinite recursion.
 		 */
 		prev_ctx = exception_enter();
-		__schedule(true);
+		__schedule(true, false);
 		exception_exit(prev_ctx);
 
 		preempt_latency_stop(1);
@ kernel/sched/core.c:5477 @ asmlinkage __visible void __sched preempt_schedule_irq(void)
 	do {
 		preempt_disable();
 		local_irq_enable();
-		__schedule(true);
+		__schedule(true, false);
 		local_irq_disable();
 		sched_preempt_enable_no_resched();
 	} while (need_resched());
@ kernel/sched/core.c:5643 @ void rt_mutex_setprio(struct task_struct *p, struct task_struct *pi_task)
 out_unlock:
 	/* Avoid rq from going away on us: */
 	preempt_disable();
-	__task_rq_unlock(rq, &rf);
 
-	balance_callback(rq);
+	rq_unpin_lock(rq, &rf);
+	__balance_callbacks(rq);
+	raw_spin_unlock(&rq->lock);
+
 	preempt_enable();
 }
 #else
@ kernel/sched/core.c:5890 @ static int __sched_setscheduler(struct task_struct *p,
 	int oldpolicy = -1, policy = attr->sched_policy;
 	int retval, oldprio, newprio, queued, running;
 	const struct sched_class *prev_class;
+	struct callback_head *head;
 	struct rq_flags rf;
 	int reset_on_fork;
 	int queue_flags = DEQUEUE_SAVE | DEQUEUE_MOVE | DEQUEUE_NOCLOCK;
@ kernel/sched/core.c:6133 @ static int __sched_setscheduler(struct task_struct *p,
 
 	/* Avoid rq from going away on us: */
 	preempt_disable();
+	head = splice_balance_callbacks(rq);
 	task_rq_unlock(rq, p, &rf);
 
 	if (pi) {
@ kernel/sched/core.c:6142 @ static int __sched_setscheduler(struct task_struct *p,
 	}
 
 	/* Run balance callbacks after we've adjusted the PI chain: */
-	balance_callback(rq);
+	balance_callbacks(rq, head);
 	preempt_enable();
 
 	return 0;
@ kernel/sched/core.c:6637 @ long sched_setaffinity(pid_t pid, const struct cpumask *in_mask)
 	}
 #endif
 again:
-	retval = __set_cpus_allowed_ptr(p, new_mask, true);
+	retval = __set_cpus_allowed_ptr(p, new_mask, SCA_CHECK);
 
 	if (!retval) {
 		cpuset_cpus_allowed(p, cpus_allowed);
@ kernel/sched/core.c:7213 @ void __init init_idle(struct task_struct *idle, int cpu)
 	 *
 	 * And since this is boot we can forgo the serialization.
 	 */
-	set_cpus_allowed_common(idle, cpumask_of(cpu));
+	set_cpus_allowed_common(idle, cpumask_of(cpu), 0);
 #endif
 	/*
 	 * We're having a chicken and egg problem, even though we are
@ kernel/sched/core.c:7240 @ void __init init_idle(struct task_struct *idle, int cpu)
 
 	/* Set the preempt count _outside_ the spinlocks! */
 	init_idle_preempt_count(idle, cpu);
-
+#ifdef CONFIG_HAVE_PREEMPT_LAZY
+	task_thread_info(idle)->preempt_lazy_count = 0;
+#endif
 	/*
 	 * The idle tasks have their own, simple scheduling class:
 	 */
@ kernel/sched/core.c:7347 @ void sched_setnuma(struct task_struct *p, int nid)
 #endif /* CONFIG_NUMA_BALANCING */
 
 #ifdef CONFIG_HOTPLUG_CPU
+
 /*
  * Ensure that the idle task is using init_mm right before its CPU goes
  * offline.
@ kernel/sched/core.c:7367 @ void idle_task_exit(void)
 	/* finish_cpu(), as ran on the BP, will clean up the active_mm state */
 }
 
-/*
- * Since this CPU is going 'away' for a while, fold any nr_active delta
- * we might have. Assumes we're called after migrate_tasks() so that the
- * nr_active count is stable. We need to take the teardown thread which
- * is calling this into account, so we hand in adjust = 1 to the load
- * calculation.
- *
- * Also see the comment "Global load-average calculations".
- */
-static void calc_load_migrate(struct rq *rq)
+static int __balance_push_cpu_stop(void *arg)
 {
-	long delta = calc_load_fold_active(rq, 1);
-	if (delta)
-		atomic_long_add(delta, &calc_load_tasks);
-}
+	struct task_struct *p = arg;
+	struct rq *rq = this_rq();
+	struct rq_flags rf;
+	int cpu;
 
-static struct task_struct *__pick_migrate_task(struct rq *rq)
-{
-	const struct sched_class *class;
-	struct task_struct *next;
+	raw_spin_lock_irq(&p->pi_lock);
+	rq_lock(rq, &rf);
 
-	for_each_class(class) {
-		next = class->pick_next_task(rq);
-		if (next) {
-			next->sched_class->put_prev_task(rq, next);
-			return next;
-		}
+	update_rq_clock(rq);
+
+	if (task_rq(p) == rq && task_on_rq_queued(p)) {
+		cpu = select_fallback_rq(rq->cpu, p);
+		rq = __migrate_task(rq, &rf, p, cpu);
 	}
 
-	/* The idle class should always have a runnable task */
-	BUG();
+	rq_unlock(rq, &rf);
+	raw_spin_unlock_irq(&p->pi_lock);
+
+	put_task_struct(p);
+
+	return 0;
 }
 
+static DEFINE_PER_CPU(struct cpu_stop_work, push_work);
+
 /*
- * Migrate all tasks from the rq, sleeping tasks will be migrated by
- * try_to_wake_up()->select_task_rq().
- *
- * Called with rq->lock held even though we'er in stop_machine() and
- * there's no concurrency possible, we hold the required locks anyway
- * because of lock validation efforts.
+ * Ensure we only run per-cpu kthreads once the CPU goes !active.
  */
-static void migrate_tasks(struct rq *dead_rq, struct rq_flags *rf)
+static void balance_push(struct rq *rq)
 {
-	struct rq *rq = dead_rq;
-	struct task_struct *next, *stop = rq->stop;
-	struct rq_flags orf = *rf;
-	int dest_cpu;
+	struct task_struct *push_task = rq->curr;
+
+	lockdep_assert_held(&rq->lock);
+	SCHED_WARN_ON(rq->cpu != smp_processor_id());
 
 	/*
-	 * Fudge the rq selection such that the below task selection loop
-	 * doesn't get stuck on the currently eligible stop task.
-	 *
-	 * We're currently inside stop_machine() and the rq is either stuck
-	 * in the stop_machine_cpu_stop() loop, or we're executing this code,
-	 * either way we should never end up calling schedule() until we're
-	 * done here.
+	 * Both the cpu-hotplug and stop task are in this case and are
+	 * required to complete the hotplug process.
 	 */
-	rq->stop = NULL;
+	if (is_per_cpu_kthread(push_task) || is_migration_disabled(push_task)) {
+		/*
+		 * If this is the idle task on the outgoing CPU try to wake
+		 * up the hotplug control thread which might wait for the
+		 * last task to vanish. The rcuwait_active() check is
+		 * accurate here because the waiter is pinned on this CPU
+		 * and can't obviously be running in parallel.
+		 *
+		 * On RT kernels this also has to check whether there are
+		 * pinned and scheduled out tasks on the runqueue. They
+		 * need to leave the migrate disabled section first.
+		 */
+		if (!rq->nr_running && !rq_has_pinned_tasks(rq) &&
+		    rcuwait_active(&rq->hotplug_wait)) {
+			raw_spin_unlock(&rq->lock);
+			rcuwait_wake_up(&rq->hotplug_wait);
+			raw_spin_lock(&rq->lock);
+		}
+		return;
+	}
 
+	get_task_struct(push_task);
 	/*
-	 * put_prev_task() and pick_next_task() sched
-	 * class method both need to have an up-to-date
-	 * value of rq->clock[_task]
+	 * Temporarily drop rq->lock such that we can wake-up the stop task.
+	 * Both preemption and IRQs are still disabled.
 	 */
-	update_rq_clock(rq);
+	raw_spin_unlock(&rq->lock);
+	stop_one_cpu_nowait(rq->cpu, __balance_push_cpu_stop, push_task,
+			    this_cpu_ptr(&push_work));
+	/*
+	 * At this point need_resched() is true and we'll take the loop in
+	 * schedule(). The next pick is obviously going to be the stop task
+	 * which is_per_cpu_kthread() and will push this task away.
+	 */
+	raw_spin_lock(&rq->lock);
+}
 
-	for (;;) {
-		/*
-		 * There's this thread running, bail when that's the only
-		 * remaining thread:
-		 */
-		if (rq->nr_running == 1)
-			break;
+static void balance_push_set(int cpu, bool on)
+{
+	struct rq *rq = cpu_rq(cpu);
+	struct rq_flags rf;
 
-		next = __pick_migrate_task(rq);
+	rq_lock_irqsave(rq, &rf);
+	if (on)
+		rq->balance_flags |= BALANCE_PUSH;
+	else
+		rq->balance_flags &= ~BALANCE_PUSH;
+	rq_unlock_irqrestore(rq, &rf);
+}
 
-		/*
-		 * Rules for changing task_struct::cpus_mask are holding
-		 * both pi_lock and rq->lock, such that holding either
-		 * stabilizes the mask.
-		 *
-		 * Drop rq->lock is not quite as disastrous as it usually is
-		 * because !cpu_active at this point, which means load-balance
-		 * will not interfere. Also, stop-machine.
-		 */
-		rq_unlock(rq, rf);
-		raw_spin_lock(&next->pi_lock);
-		rq_relock(rq, rf);
+/*
+ * Invoked from a CPUs hotplug control thread after the CPU has been marked
+ * inactive. All tasks which are not per CPU kernel threads are either
+ * pushed off this CPU now via balance_push() or placed on a different CPU
+ * during wakeup. Wait until the CPU is quiescent.
+ */
+static void balance_hotplug_wait(void)
+{
+	struct rq *rq = this_rq();
 
-		/*
-		 * Since we're inside stop-machine, _nothing_ should have
-		 * changed the task, WARN if weird stuff happened, because in
-		 * that case the above rq->lock drop is a fail too.
-		 */
-		if (WARN_ON(task_rq(next) != rq || !task_on_rq_queued(next))) {
-			raw_spin_unlock(&next->pi_lock);
-			continue;
-		}
+	rcuwait_wait_event(&rq->hotplug_wait,
+			   rq->nr_running == 1 && !rq_has_pinned_tasks(rq),
+			   TASK_UNINTERRUPTIBLE);
+}
 
-		/* Find suitable destination for @next, with force if needed. */
-		dest_cpu = select_fallback_rq(dead_rq->cpu, next);
-		rq = __migrate_task(rq, rf, next, dest_cpu);
-		if (rq != dead_rq) {
-			rq_unlock(rq, rf);
-			rq = dead_rq;
-			*rf = orf;
-			rq_relock(rq, rf);
-		}
-		raw_spin_unlock(&next->pi_lock);
-	}
+#else
+
+static inline void balance_push(struct rq *rq)
+{
+}
 
-	rq->stop = stop;
+static inline void balance_push_set(int cpu, bool on)
+{
+}
+
+static inline void balance_hotplug_wait(void)
+{
 }
+
 #endif /* CONFIG_HOTPLUG_CPU */
 
 void set_rq_online(struct rq *rq)
@ kernel/sched/core.c:7572 @ int sched_cpu_activate(unsigned int cpu)
 	struct rq *rq = cpu_rq(cpu);
 	struct rq_flags rf;
 
+	balance_push_set(cpu, false);
+
 #ifdef CONFIG_SCHED_SMT
 	/*
 	 * When going up, increment the number of cores with SMT present.
@ kernel/sched/core.c:7609 @ int sched_cpu_activate(unsigned int cpu)
 
 int sched_cpu_deactivate(unsigned int cpu)
 {
+	struct rq *rq = cpu_rq(cpu);
+	struct rq_flags rf;
 	int ret;
 
 	set_cpu_active(cpu, false);
@ kernel/sched/core.c:7623 @ int sched_cpu_deactivate(unsigned int cpu)
 	 */
 	synchronize_rcu();
 
+	balance_push_set(cpu, true);
+
+	rq_lock_irqsave(rq, &rf);
+	if (rq->rd) {
+		update_rq_clock(rq);
+		BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span));
+		set_rq_offline(rq);
+	}
+	rq_unlock_irqrestore(rq, &rf);
+
 #ifdef CONFIG_SCHED_SMT
 	/*
 	 * When going down, decrement the number of cores with SMT present.
@ kernel/sched/core.c:7646 @ int sched_cpu_deactivate(unsigned int cpu)
 
 	ret = cpuset_cpu_inactive(cpu);
 	if (ret) {
+		balance_push_set(cpu, false);
 		set_cpu_active(cpu, true);
 		return ret;
 	}
@ kernel/sched/core.c:7670 @ int sched_cpu_starting(unsigned int cpu)
 }
 
 #ifdef CONFIG_HOTPLUG_CPU
+
+/*
+ * Invoked immediately before the stopper thread is invoked to bring the
+ * CPU down completely. At this point all per CPU kthreads except the
+ * hotplug thread (current) and the stopper thread (inactive) have been
+ * either parked or have been unbound from the outgoing CPU. Ensure that
+ * any of those which might be on the way out are gone.
+ *
+ * If after this point a bound task is being woken on this CPU then the
+ * responsible hotplug callback has failed to do it's job.
+ * sched_cpu_dying() will catch it with the appropriate fireworks.
+ */
+int sched_cpu_wait_empty(unsigned int cpu)
+{
+	balance_hotplug_wait();
+	return 0;
+}
+
+/*
+ * Since this CPU is going 'away' for a while, fold any nr_active delta we
+ * might have. Called from the CPU stopper task after ensuring that the
+ * stopper is the last running task on the CPU, so nr_active count is
+ * stable. We need to take the teardown thread which is calling this into
+ * account, so we hand in adjust = 1 to the load calculation.
+ *
+ * Also see the comment "Global load-average calculations".
+ */
+static void calc_load_migrate(struct rq *rq)
+{
+	long delta = calc_load_fold_active(rq, 1);
+
+	if (delta)
+		atomic_long_add(delta, &calc_load_tasks);
+}
+
 int sched_cpu_dying(unsigned int cpu)
 {
 	struct rq *rq = cpu_rq(cpu);
@ kernel/sched/core.c:7714 @ int sched_cpu_dying(unsigned int cpu)
 	sched_tick_stop(cpu);
 
 	rq_lock_irqsave(rq, &rf);
-	if (rq->rd) {
-		BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span));
-		set_rq_offline(rq);
-	}
-	migrate_tasks(rq, &rf);
-	BUG_ON(rq->nr_running != 1);
+	BUG_ON(rq->nr_running != 1 || rq_has_pinned_tasks(rq));
 	rq_unlock_irqrestore(rq, &rf);
 
 	calc_load_migrate(rq);
@ kernel/sched/core.c:7921 @ void __init sched_init(void)
 
 		rq_csd_init(rq, &rq->nohz_csd, nohz_csd_func);
 #endif
+#ifdef CONFIG_HOTPLUG_CPU
+		rcuwait_init(&rq->hotplug_wait);
+#endif
 #endif /* CONFIG_SMP */
 		hrtick_rq_init(rq);
 		atomic_set(&rq->nr_iowait, 0);
@ kernel/sched/core.c:7964 @ void __init sched_init(void)
 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
 static inline int preempt_count_equals(int preempt_offset)
 {
-	int nested = preempt_count() + rcu_preempt_depth();
+	int nested = preempt_count() + sched_rcu_preempt_depth();
 
 	return (nested == preempt_offset);
 }
@ kernel/sched/core.c:8061 @ void __cant_sleep(const char *file, int line, int preempt_offset)
 	add_taint(TAINT_WARN, LOCKDEP_STILL_OK);
 }
 EXPORT_SYMBOL_GPL(__cant_sleep);
+
+#ifdef CONFIG_SMP
+void __cant_migrate(const char *file, int line)
+{
+	static unsigned long prev_jiffy;
+
+	if (irqs_disabled())
+		return;
+
+	if (is_migration_disabled(current))
+		return;
+
+	if (!IS_ENABLED(CONFIG_PREEMPT_COUNT))
+		return;
+
+	if (preempt_count() > 0)
+		return;
+
+	if (time_before(jiffies, prev_jiffy + HZ) && prev_jiffy)
+		return;
+	prev_jiffy = jiffies;
+
+	pr_err("BUG: assuming non migratable context at %s:%d\n", file, line);
+	pr_err("in_atomic(): %d, irqs_disabled(): %d, migration_disabled() %u pid: %d, name: %s\n",
+	       in_atomic(), irqs_disabled(), is_migration_disabled(current),
+	       current->pid, current->comm);
+
+	debug_show_held_locks(current);
+	dump_stack();
+	add_taint(TAINT_WARN, LOCKDEP_STILL_OK);
+}
+EXPORT_SYMBOL_GPL(__cant_migrate);
+#endif
 #endif
 
 #ifdef CONFIG_MAGIC_SYSRQ
@ kernel/sched/cpudeadline.c:123 @ int cpudl_find(struct cpudl *cp, struct task_struct *p,
 	const struct sched_dl_entity *dl_se = &p->dl;
 
 	if (later_mask &&
-	    cpumask_and(later_mask, cp->free_cpus, p->cpus_ptr)) {
+	    cpumask_and(later_mask, cp->free_cpus, &p->cpus_mask)) {
 		unsigned long cap, max_cap = 0;
 		int cpu, max_cpu = -1;
 
@ kernel/sched/cpudeadline.c:154 @ int cpudl_find(struct cpudl *cp, struct task_struct *p,
 
 		WARN_ON(best_cpu != -1 && !cpu_present(best_cpu));
 
-		if (cpumask_test_cpu(best_cpu, p->cpus_ptr) &&
+		if (cpumask_test_cpu(best_cpu, &p->cpus_mask) &&
 		    dl_time_before(dl_se->deadline, cp->elements[0].dl)) {
 			if (later_mask)
 				cpumask_set_cpu(best_cpu, later_mask);
@ kernel/sched/cpupri.c:76 @ static inline int __cpupri_find(struct cpupri *cp, struct task_struct *p,
 	if (skip)
 		return 0;
 
-	if (cpumask_any_and(p->cpus_ptr, vec->mask) >= nr_cpu_ids)
+	if (cpumask_any_and(&p->cpus_mask, vec->mask) >= nr_cpu_ids)
 		return 0;
 
 	if (lowest_mask) {
-		cpumask_and(lowest_mask, p->cpus_ptr, vec->mask);
+		cpumask_and(lowest_mask, &p->cpus_mask, vec->mask);
 
 		/*
 		 * We have to ensure that we have at least one bit
@ kernel/sched/cputime.c:47 @ static void irqtime_account_delta(struct irqtime *irqtime, u64 delta,
 }
 
 /*
- * Called before incrementing preempt_count on {soft,}irq_enter
+ * Called after incrementing preempt_count on {soft,}irq_enter
  * and before decrementing preempt_count on {soft,}irq_exit.
  */
-void irqtime_account_irq(struct task_struct *curr)
+void irqtime_account_irq(struct task_struct *curr, unsigned int offset)
 {
 	struct irqtime *irqtime = this_cpu_ptr(&cpu_irqtime);
+	unsigned int pc;
 	s64 delta;
 	int cpu;
 
@ kernel/sched/cputime.c:63 @ void irqtime_account_irq(struct task_struct *curr)
 	cpu = smp_processor_id();
 	delta = sched_clock_cpu(cpu) - irqtime->irq_start_time;
 	irqtime->irq_start_time += delta;
+	pc = irq_count() - offset;
 
 	/*
 	 * We do not account for softirq time from ksoftirqd here.
@ kernel/sched/cputime.c:71 @ void irqtime_account_irq(struct task_struct *curr)
 	 * in that case, so as not to confuse scheduler with a special task
 	 * that do not consume any time, but still wants to run.
 	 */
-	if (hardirq_count())
+	if (pc & HARDIRQ_MASK)
 		irqtime_account_delta(irqtime, delta, CPUTIME_IRQ);
-	else if (in_serving_softirq() && curr != this_cpu_ksoftirqd())
+	else if ((pc & SOFTIRQ_OFFSET) && curr != this_cpu_ksoftirqd())
 		irqtime_account_delta(irqtime, delta, CPUTIME_SOFTIRQ);
 }
-EXPORT_SYMBOL_GPL(irqtime_account_irq);
 
 static u64 irqtime_tick_accounted(u64 maxtime)
 {
@ kernel/sched/cputime.c:422 @ void vtime_task_switch(struct task_struct *prev)
 }
 # endif
 
-/*
- * Archs that account the whole time spent in the idle task
- * (outside irq) as idle time can rely on this and just implement
- * vtime_account_kernel() and vtime_account_idle(). Archs that
- * have other meaning of the idle time (s390 only includes the
- * time spent by the CPU when it's in low power mode) must override
- * vtime_account().
- */
-#ifndef __ARCH_HAS_VTIME_ACCOUNT
-void vtime_account_irq_enter(struct task_struct *tsk)
+void vtime_account_irq(struct task_struct *tsk, unsigned int offset)
 {
-	if (!in_interrupt() && is_idle_task(tsk))
+	unsigned int pc = irq_count() - offset;
+
+	if (pc & HARDIRQ_OFFSET) {
+		vtime_account_hardirq(tsk);
+	} else if (pc & SOFTIRQ_OFFSET) {
+		vtime_account_softirq(tsk);
+	} else if (!IS_ENABLED(CONFIG_HAVE_VIRT_CPU_ACCOUNTING_IDLE) &&
+		   is_idle_task(tsk)) {
 		vtime_account_idle(tsk);
-	else
+	} else {
 		vtime_account_kernel(tsk);
+	}
 }
-EXPORT_SYMBOL_GPL(vtime_account_irq_enter);
-#endif /* __ARCH_HAS_VTIME_ACCOUNT */
 
 void cputime_adjust(struct task_cputime *curr, struct prev_cputime *prev,
 		    u64 *ut, u64 *st)
@ kernel/sched/deadline.c:568 @ static int push_dl_task(struct rq *rq);
 
 static inline bool need_pull_dl_task(struct rq *rq, struct task_struct *prev)
 {
-	return dl_task(prev);
+	return rq->online && dl_task(prev);
 }
 
 static DEFINE_PER_CPU(struct callback_head, dl_push_head);
@ kernel/sched/deadline.c:1922 @ static void task_fork_dl(struct task_struct *p)
 static int pick_dl_task(struct rq *rq, struct task_struct *p, int cpu)
 {
 	if (!task_running(rq, p) &&
-	    cpumask_test_cpu(cpu, p->cpus_ptr))
+	    cpumask_test_cpu(cpu, &p->cpus_mask))
 		return 1;
 	return 0;
 }
@ kernel/sched/deadline.c:2012 @ static int find_later_rq(struct task_struct *task)
 				return this_cpu;
 			}
 
-			best_cpu = cpumask_first_and(later_mask,
-							sched_domain_span(sd));
+			best_cpu = cpumask_any_and_distribute(later_mask,
+							      sched_domain_span(sd));
 			/*
 			 * Last chance: if a CPU being in both later_mask
 			 * and current sd span is valid, that becomes our
@ kernel/sched/deadline.c:2035 @ static int find_later_rq(struct task_struct *task)
 	if (this_cpu != -1)
 		return this_cpu;
 
-	cpu = cpumask_any(later_mask);
+	cpu = cpumask_any_distribute(later_mask);
 	if (cpu < nr_cpu_ids)
 		return cpu;
 
@ kernel/sched/deadline.c:2072 @ static struct rq *find_lock_later_rq(struct task_struct *task, struct rq *rq)
 		/* Retry if something changed. */
 		if (double_lock_balance(rq, later_rq)) {
 			if (unlikely(task_rq(task) != rq ||
-				     !cpumask_test_cpu(later_rq->cpu, task->cpus_ptr) ||
+				     !cpumask_test_cpu(later_rq->cpu, &task->cpus_mask) ||
 				     task_running(rq, task) ||
 				     !dl_task(task) ||
 				     !task_on_rq_queued(task))) {
@ kernel/sched/deadline.c:2139 @ static int push_dl_task(struct rq *rq)
 		return 0;
 
 retry:
+	if (is_migration_disabled(next_task))
+		return 0;
+
 	if (WARN_ON(next_task == rq->curr))
 		return 0;
 
@ kernel/sched/deadline.c:2219 @ static void push_dl_tasks(struct rq *rq)
 static void pull_dl_task(struct rq *this_rq)
 {
 	int this_cpu = this_rq->cpu, cpu;
-	struct task_struct *p;
+	struct task_struct *p, *push_task;
 	bool resched = false;
 	struct rq *src_rq;
 	u64 dmin = LONG_MAX;
@ kernel/sched/deadline.c:2249 @ static void pull_dl_task(struct rq *this_rq)
 			continue;
 
 		/* Might drop this_rq->lock */
+		push_task = NULL;
 		double_lock_balance(this_rq, src_rq);
 
 		/*
@ kernel/sched/deadline.c:2281 @ static void pull_dl_task(struct rq *this_rq)
 					   src_rq->curr->dl.deadline))
 				goto skip;
 
-			resched = true;
-
-			deactivate_task(src_rq, p, 0);
-			set_task_cpu(p, this_cpu);
-			activate_task(this_rq, p, 0);
-			dmin = p->dl.deadline;
+			if (is_migration_disabled(p)) {
+				trace_sched_migrate_pull_tp(p);
+				push_task = get_push_task(src_rq);
+			} else {
+				deactivate_task(src_rq, p, 0);
+				set_task_cpu(p, this_cpu);
+				activate_task(this_rq, p, 0);
+				dmin = p->dl.deadline;
+				resched = true;
+			}
 
 			/* Is there any other task even earlier? */
 		}
 skip:
 		double_unlock_balance(this_rq, src_rq);
+
+		if (push_task) {
+			raw_spin_unlock(&this_rq->lock);
+			stop_one_cpu_nowait(src_rq->cpu, push_cpu_stop,
+					    push_task, &src_rq->push_work);
+			raw_spin_lock(&this_rq->lock);
+		}
 	}
 
 	if (resched)
@ kernel/sched/deadline.c:2326 @ static void task_woken_dl(struct rq *rq, struct task_struct *p)
 }
 
 static void set_cpus_allowed_dl(struct task_struct *p,
-				const struct cpumask *new_mask)
+				const struct cpumask *new_mask,
+				u32 flags)
 {
 	struct root_domain *src_rd;
 	struct rq *rq;
@ kernel/sched/deadline.c:2356 @ static void set_cpus_allowed_dl(struct task_struct *p,
 		raw_spin_unlock(&src_dl_b->lock);
 	}
 
-	set_cpus_allowed_common(p, new_mask);
+	set_cpus_allowed_common(p, new_mask, flags);
 }
 
 /* Assumes rq->lock is held */
@ kernel/sched/deadline.c:2551 @ const struct sched_class dl_sched_class
 	.rq_online              = rq_online_dl,
 	.rq_offline             = rq_offline_dl,
 	.task_woken		= task_woken_dl,
+	.find_lock_rq		= find_lock_later_rq,
 #endif
 
 	.task_tick		= task_tick_dl,
@ kernel/sched/fair.c:4400 @ check_preempt_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr)
 	ideal_runtime = sched_slice(cfs_rq, curr);
 	delta_exec = curr->sum_exec_runtime - curr->prev_sum_exec_runtime;
 	if (delta_exec > ideal_runtime) {
-		resched_curr(rq_of(cfs_rq));
+		resched_curr_lazy(rq_of(cfs_rq));
 		/*
 		 * The current task ran long enough, ensure it doesn't get
 		 * re-elected due to buddy favours.
@ kernel/sched/fair.c:4424 @ check_preempt_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr)
 		return;
 
 	if (delta > ideal_runtime)
-		resched_curr(rq_of(cfs_rq));
+		resched_curr_lazy(rq_of(cfs_rq));
 }
 
 static void
@ kernel/sched/fair.c:4567 @ entity_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr, int queued)
 	 * validating it and just reschedule.
 	 */
 	if (queued) {
-		resched_curr(rq_of(cfs_rq));
+		resched_curr_lazy(rq_of(cfs_rq));
 		return;
 	}
 	/*
@ kernel/sched/fair.c:4704 @ static void __account_cfs_rq_runtime(struct cfs_rq *cfs_rq, u64 delta_exec)
 	 * hierarchy can be throttled
 	 */
 	if (!assign_cfs_rq_runtime(cfs_rq) && likely(cfs_rq->curr))
-		resched_curr(rq_of(cfs_rq));
+		resched_curr_lazy(rq_of(cfs_rq));
 }
 
 static __always_inline
@ kernel/sched/fair.c:5439 @ static void hrtick_start_fair(struct rq *rq, struct task_struct *p)
 
 		if (delta < 0) {
 			if (rq->curr == p)
-				resched_curr(rq);
+				resched_curr_lazy(rq);
 			return;
 		}
 		hrtick_start(rq, delta);
@ kernel/sched/fair.c:7020 @ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_
 	return;
 
 preempt:
-	resched_curr(rq);
+	resched_curr_lazy(rq);
 	/*
 	 * Only set the backward buddy when the current task is still
 	 * on the rq. This can happen when a wakeup gets interleaved
@ kernel/sched/fair.c:10780 @ static void task_fork_fair(struct task_struct *p)
 		 * 'current' within the tree based on its new key value.
 		 */
 		swap(curr->vruntime, se->vruntime);
-		resched_curr(rq);
+		resched_curr_lazy(rq);
 	}
 
 	se->vruntime -= cfs_rq->min_vruntime;
@ kernel/sched/fair.c:10807 @ prio_changed_fair(struct rq *rq, struct task_struct *p, int oldprio)
 	 */
 	if (rq->curr == p) {
 		if (p->prio > oldprio)
-			resched_curr(rq);
+			resched_curr_lazy(rq);
 	} else
 		check_preempt_curr(rq, p, 0);
 }
@ kernel/sched/features.h:48 @ SCHED_FEAT(DOUBLE_TICK, false)
  */
 SCHED_FEAT(NONTASK_CAPACITY, true)
 
+#ifdef CONFIG_PREEMPT_RT
+SCHED_FEAT(TTWU_QUEUE, false)
+# ifdef CONFIG_PREEMPT_LAZY
+SCHED_FEAT(PREEMPT_LAZY, true)
+# endif
+#else
+
 /*
  * Queue remote wakeups on the target CPU and process them
  * using the scheduler IPI. Reduces rq->lock contention/bounces.
  */
 SCHED_FEAT(TTWU_QUEUE, true)
+#endif
 
 /*
  * When doing wakeups, attempt to limit superfluous scans of the LLC domain.
@ kernel/sched/rt.c:268 @ static void pull_rt_task(struct rq *this_rq);
 static inline bool need_pull_rt_task(struct rq *rq, struct task_struct *prev)
 {
 	/* Try to pull RT tasks here if we lower this rq's prio */
-	return rq->rt.highest_prio.curr > prev->prio;
+	return rq->online && rq->rt.highest_prio.curr > prev->prio;
 }
 
 static inline int rt_overloaded(struct rq *rq)
@ kernel/sched/rt.c:1661 @ static void put_prev_task_rt(struct rq *rq, struct task_struct *p)
 static int pick_rt_task(struct rq *rq, struct task_struct *p, int cpu)
 {
 	if (!task_running(rq, p) &&
-	    cpumask_test_cpu(cpu, p->cpus_ptr))
+	    cpumask_test_cpu(cpu, &p->cpus_mask))
 		return 1;
 
 	return 0;
@ kernel/sched/rt.c:1755 @ static int find_lowest_rq(struct task_struct *task)
 				return this_cpu;
 			}
 
-			best_cpu = cpumask_first_and(lowest_mask,
-						     sched_domain_span(sd));
+			best_cpu = cpumask_any_and_distribute(lowest_mask,
+							      sched_domain_span(sd));
 			if (best_cpu < nr_cpu_ids) {
 				rcu_read_unlock();
 				return best_cpu;
@ kernel/sched/rt.c:1773 @ static int find_lowest_rq(struct task_struct *task)
 	if (this_cpu != -1)
 		return this_cpu;
 
-	cpu = cpumask_any(lowest_mask);
+	cpu = cpumask_any_distribute(lowest_mask);
 	if (cpu < nr_cpu_ids)
 		return cpu;
 
@ kernel/sched/rt.c:1814 @ static struct rq *find_lock_lowest_rq(struct task_struct *task, struct rq *rq)
 			 * Also make sure that it wasn't scheduled on its rq.
 			 */
 			if (unlikely(task_rq(task) != rq ||
-				     !cpumask_test_cpu(lowest_rq->cpu, task->cpus_ptr) ||
+				     !cpumask_test_cpu(lowest_rq->cpu, &task->cpus_mask) ||
 				     task_running(rq, task) ||
 				     !rt_task(task) ||
 				     !task_on_rq_queued(task))) {
@ kernel/sched/rt.c:1862 @ static struct task_struct *pick_next_pushable_task(struct rq *rq)
  * running task can migrate over to a CPU that is running a task
  * of lesser priority.
  */
-static int push_rt_task(struct rq *rq)
+static int push_rt_task(struct rq *rq, bool pull)
 {
 	struct task_struct *next_task;
 	struct rq *lowest_rq;
@ kernel/sched/rt.c:1876 @ static int push_rt_task(struct rq *rq)
 		return 0;
 
 retry:
+	if (is_migration_disabled(next_task)) {
+		struct task_struct *push_task = NULL;
+		int cpu;
+
+		if (!pull)
+			return 0;
+
+		trace_sched_migrate_pull_tp(next_task);
+
+		if (rq->push_busy)
+			return 0;
+
+		cpu = find_lowest_rq(rq->curr);
+		if (cpu == -1 || cpu == rq->cpu)
+			return 0;
+
+		/*
+		 * Given we found a CPU with lower priority than @next_task,
+		 * therefore it should be running. However we cannot migrate it
+		 * to this other CPU, instead attempt to push the current
+		 * running task on this CPU away.
+		 */
+		push_task = get_push_task(rq);
+		if (push_task) {
+			raw_spin_unlock(&rq->lock);
+			stop_one_cpu_nowait(rq->cpu, push_cpu_stop,
+					    push_task, &rq->push_work);
+			raw_spin_lock(&rq->lock);
+		}
+
+		return 0;
+	}
+
 	if (WARN_ON(next_task == rq->curr))
 		return 0;
 
@ kernel/sched/rt.c:1963 @ static int push_rt_task(struct rq *rq)
 	deactivate_task(rq, next_task, 0);
 	set_task_cpu(next_task, lowest_rq->cpu);
 	activate_task(lowest_rq, next_task, 0);
-	ret = 1;
-
 	resched_curr(lowest_rq);
+	ret = 1;
 
 	double_unlock_balance(rq, lowest_rq);
-
 out:
 	put_task_struct(next_task);
 
@ kernel/sched/rt.c:1976 @ static int push_rt_task(struct rq *rq)
 static void push_rt_tasks(struct rq *rq)
 {
 	/* push_rt_task will return true if it moved an RT */
-	while (push_rt_task(rq))
+	while (push_rt_task(rq, false))
 		;
 }
 
@ kernel/sched/rt.c:2129 @ void rto_push_irq_work_func(struct irq_work *work)
 	 */
 	if (has_pushable_tasks(rq)) {
 		raw_spin_lock(&rq->lock);
-		push_rt_tasks(rq);
+		while (push_rt_task(rq, true))
+			;
 		raw_spin_unlock(&rq->lock);
 	}
 
@ kernel/sched/rt.c:2155 @ static void pull_rt_task(struct rq *this_rq)
 {
 	int this_cpu = this_rq->cpu, cpu;
 	bool resched = false;
-	struct task_struct *p;
+	struct task_struct *p, *push_task;
 	struct rq *src_rq;
 	int rt_overload_count = rt_overloaded(this_rq);
 
@ kernel/sched/rt.c:2202 @ static void pull_rt_task(struct rq *this_rq)
 		 * double_lock_balance, and another CPU could
 		 * alter this_rq
 		 */
+		push_task = NULL;
 		double_lock_balance(this_rq, src_rq);
 
 		/*
@ kernel/sched/rt.c:2230 @ static void pull_rt_task(struct rq *this_rq)
 			if (p->prio < src_rq->curr->prio)
 				goto skip;
 
-			resched = true;
-
-			deactivate_task(src_rq, p, 0);
-			set_task_cpu(p, this_cpu);
-			activate_task(this_rq, p, 0);
+			if (is_migration_disabled(p)) {
+				trace_sched_migrate_pull_tp(p);
+				push_task = get_push_task(src_rq);
+			} else {
+				deactivate_task(src_rq, p, 0);
+				set_task_cpu(p, this_cpu);
+				activate_task(this_rq, p, 0);
+				resched = true;
+			}
 			/*
 			 * We continue with the search, just in
 			 * case there's an even higher prio task
@ kernel/sched/rt.c:2248 @ static void pull_rt_task(struct rq *this_rq)
 		}
 skip:
 		double_unlock_balance(this_rq, src_rq);
+
+		if (push_task) {
+			raw_spin_unlock(&this_rq->lock);
+			stop_one_cpu_nowait(src_rq->cpu, push_cpu_stop,
+					    push_task, &src_rq->push_work);
+			raw_spin_lock(&this_rq->lock);
+		}
 	}
 
 	if (resched)
@ kernel/sched/rt.c:2503 @ const struct sched_class rt_sched_class
 	.rq_offline             = rq_offline_rt,
 	.task_woken		= task_woken_rt,
 	.switched_from		= switched_from_rt,
+	.find_lock_rq		= find_lock_lowest_rq,
 #endif
 
 	.task_tick		= task_tick_rt,
@ kernel/sched/sched.h:979 @ struct rq {
 	unsigned long		cpu_capacity_orig;
 
 	struct callback_head	*balance_callback;
+	unsigned char		balance_flags;
 
 	unsigned char		nohz_idle_balance;
 	unsigned char		idle_balance;
@ kernel/sched/sched.h:1010 @ struct rq {
 
 	/* This is used to determine avg_idle's max value */
 	u64			max_idle_balance_cost;
+
+#ifdef CONFIG_HOTPLUG_CPU
+	struct rcuwait		hotplug_wait;
+#endif
 #endif /* CONFIG_SMP */
 
 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
@ kernel/sched/sched.h:1060 @ struct rq {
 	/* Must be inspected within a rcu lock section */
 	struct cpuidle_state	*idle_state;
 #endif
+
+#ifdef CONFIG_SMP
+	unsigned int		nr_pinned;
+#endif
+	unsigned int		push_busy;
+	struct cpu_stop_work	push_work;
 };
 
 #ifdef CONFIG_FAIR_GROUP_SCHED
@ kernel/sched/sched.h:1093 @ static inline int cpu_of(struct rq *rq)
 #endif
 }
 
+#define MDF_PUSH	0x01
+
+static inline bool is_migration_disabled(struct task_struct *p)
+{
+#ifdef CONFIG_SMP
+	return p->migration_disabled;
+#else
+	return false;
+#endif
+}
 
 #ifdef CONFIG_SCHED_SMT
 extern void __update_idle_core(struct rq *rq);
@ kernel/sched/sched.h:1249 @ static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
 	rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
 	rf->clock_update_flags = 0;
 #endif
+#ifdef CONFIG_SMP
+	SCHED_WARN_ON(rq->balance_callback);
+#endif
 }
 
 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
@ kernel/sched/sched.h:1413 @ init_numa_balancing(unsigned long clone_flags, struct task_struct *p)
 
 #ifdef CONFIG_SMP
 
+#define BALANCE_WORK	0x01
+#define BALANCE_PUSH	0x02
+
 static inline void
 queue_balance_callback(struct rq *rq,
 		       struct callback_head *head,
@ kernel/sched/sched.h:1423 @ queue_balance_callback(struct rq *rq,
 {
 	lockdep_assert_held(&rq->lock);
 
-	if (unlikely(head->next))
+	if (unlikely(head->next || (rq->balance_flags & BALANCE_PUSH)))
 		return;
 
 	head->func = (void (*)(struct callback_head *))func;
 	head->next = rq->balance_callback;
 	rq->balance_callback = head;
+	rq->balance_flags |= BALANCE_WORK;
 }
 
 #define rcu_dereference_check_sched_domain(p) \
@ kernel/sched/sched.h:1756 @ static inline int task_on_rq_migrating(struct task_struct *p)
 #define WF_FORK			0x02		/* Child wakeup after fork */
 #define WF_MIGRATED		0x04		/* Internal use, task got migrated */
 #define WF_ON_CPU		0x08		/* Wakee is on_cpu */
+#define WF_LOCK_SLEEPER		0x10		/* Wakeup spinlock "sleeper" */
 
 /*
  * To aid in avoiding the subversion of "niceness" due to uneven distribution
@ kernel/sched/sched.h:1838 @ struct sched_class {
 	void (*task_woken)(struct rq *this_rq, struct task_struct *task);
 
 	void (*set_cpus_allowed)(struct task_struct *p,
-				 const struct cpumask *newmask);
+				 const struct cpumask *newmask,
+				 u32 flags);
 
 	void (*rq_online)(struct rq *rq);
 	void (*rq_offline)(struct rq *rq);
+
+	struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq);
 #endif
 
 	void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
@ kernel/sched/sched.h:1928 @ static inline bool sched_fair_runnable(struct rq *rq)
 extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
 extern struct task_struct *pick_next_task_idle(struct rq *rq);
 
+#define SCA_CHECK		0x01
+#define SCA_MIGRATE_DISABLE	0x02
+#define SCA_MIGRATE_ENABLE	0x04
+
 #ifdef CONFIG_SMP
 
 extern void update_group_capacity(struct sched_domain *sd, int cpu);
 
 extern void trigger_load_balance(struct rq *rq);
 
-extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask);
+extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask, u32 flags);
+
+static inline struct task_struct *get_push_task(struct rq *rq)
+{
+	struct task_struct *p = rq->curr;
+
+	lockdep_assert_held(&rq->lock);
+
+	if (rq->push_busy)
+		return NULL;
+
+	if (p->nr_cpus_allowed == 1)
+		return NULL;
+
+	if (p->migration_disabled)
+		return NULL;
+
+	rq->push_busy = true;
+	return get_task_struct(p);
+}
+
+extern int push_cpu_stop(void *arg);
 
 #endif
 
@ kernel/sched/sched.h:2003 @ extern void reweight_task(struct task_struct *p, int prio);
 extern void resched_curr(struct rq *rq);
 extern void resched_cpu(int cpu);
 
+#ifdef CONFIG_PREEMPT_LAZY
+extern void resched_curr_lazy(struct rq *rq);
+#else
+static inline void resched_curr_lazy(struct rq *rq)
+{
+	resched_curr(rq);
+}
+#endif
+
 extern struct rt_bandwidth def_rt_bandwidth;
 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
 
@ kernel/sched/swait.c:67 @ void swake_up_all(struct swait_queue_head *q)
 	struct swait_queue *curr;
 	LIST_HEAD(tmp);
 
+	WARN_ON(irqs_disabled());
 	raw_spin_lock_irq(&q->lock);
 	list_splice_init(&q->task_list, &tmp);
 	while (!list_empty(&tmp)) {
@ kernel/sched/topology.c:517 @ static int init_rootdomain(struct root_domain *rd)
 	rd->rto_cpu = -1;
 	raw_spin_lock_init(&rd->rto_lock);
 	init_irq_work(&rd->rto_push_work, rto_push_irq_work_func);
+	atomic_or(IRQ_WORK_HARD_IRQ, &rd->rto_push_work.flags);
 #endif
 
 	init_dl_bw(&rd->dl_bw);
@ kernel/signal.c:23 @
 #include <linux/sched/task.h>
 #include <linux/sched/task_stack.h>
 #include <linux/sched/cputime.h>
+#include <linux/sched/rt.h>
 #include <linux/file.h>
 #include <linux/fs.h>
 #include <linux/proc_fs.h>
@ kernel/signal.c:408 @ void task_join_group_stop(struct task_struct *task)
 	task_set_jobctl_pending(task, mask | JOBCTL_STOP_PENDING);
 }
 
+static inline struct sigqueue *get_task_cache(struct task_struct *t)
+{
+	struct sigqueue *q = t->sigqueue_cache;
+
+	if (cmpxchg(&t->sigqueue_cache, q, NULL) != q)
+		return NULL;
+	return q;
+}
+
+static inline int put_task_cache(struct task_struct *t, struct sigqueue *q)
+{
+	if (cmpxchg(&t->sigqueue_cache, NULL, q) == NULL)
+		return 0;
+	return 1;
+}
+
 /*
  * allocate a new signal queue record
  * - this may be called without locks if and only if t == current, otherwise an
  *   appropriate lock must be held to stop the target task from exiting
  */
 static struct sigqueue *
-__sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimit)
+__sigqueue_do_alloc(int sig, struct task_struct *t, gfp_t flags,
+		    int override_rlimit, int fromslab)
 {
 	struct sigqueue *q = NULL;
 	struct user_struct *user;
@ kernel/signal.c:453 @ __sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimi
 	rcu_read_unlock();
 
 	if (override_rlimit || likely(sigpending <= task_rlimit(t, RLIMIT_SIGPENDING))) {
-		q = kmem_cache_alloc(sigqueue_cachep, flags);
+		if (!fromslab)
+			q = get_task_cache(t);
+		if (!q)
+			q = kmem_cache_alloc(sigqueue_cachep, flags);
 	} else {
 		print_dropped_signal(sig);
 	}
@ kernel/signal.c:473 @ __sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimi
 	return q;
 }
 
+static struct sigqueue *
+__sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags,
+		 int override_rlimit)
+{
+	return __sigqueue_do_alloc(sig, t, flags, override_rlimit, 0);
+}
+
 static void __sigqueue_free(struct sigqueue *q)
 {
 	if (q->flags & SIGQUEUE_PREALLOC)
@ kernel/signal.c:489 @ static void __sigqueue_free(struct sigqueue *q)
 	kmem_cache_free(sigqueue_cachep, q);
 }
 
+static void sigqueue_free_current(struct sigqueue *q)
+{
+	struct user_struct *up;
+
+	if (q->flags & SIGQUEUE_PREALLOC)
+		return;
+
+	up = q->user;
+	if (rt_prio(current->normal_prio) && !put_task_cache(current, q)) {
+		if (atomic_dec_and_test(&up->sigpending))
+			free_uid(up);
+	} else
+		  __sigqueue_free(q);
+}
+
 void flush_sigqueue(struct sigpending *queue)
 {
 	struct sigqueue *q;
@ kernel/signal.c:516 @ void flush_sigqueue(struct sigpending *queue)
 	}
 }
 
+/*
+ * Called from __exit_signal. Flush tsk->pending and
+ * tsk->sigqueue_cache
+ */
+void flush_task_sigqueue(struct task_struct *tsk)
+{
+	struct sigqueue *q;
+
+	flush_sigqueue(&tsk->pending);
+
+	q = get_task_cache(tsk);
+	if (q)
+		kmem_cache_free(sigqueue_cachep, q);
+}
+
 /*
  * Flush all pending signals for this kthread.
  */
@ kernel/signal.c:655 @ static void collect_signal(int sig, struct sigpending *list, kernel_siginfo_t *i
 			(info->si_code == SI_TIMER) &&
 			(info->si_sys_private);
 
-		__sigqueue_free(first);
+		sigqueue_free_current(first);
 	} else {
 		/*
 		 * Ok, it wasn't in the queue.  This must be
@ kernel/signal.c:692 @ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, kernel_siginfo_t *in
 	bool resched_timer = false;
 	int signr;
 
+	WARN_ON_ONCE(tsk != current);
+
 	/* We only dequeue private signals from ourselves, we don't let
 	 * signalfd steal them
 	 */
@ kernel/signal.c:1377 @ force_sig_info_to_task(struct kernel_siginfo *info, struct task_struct *t)
 	struct k_sigaction *action;
 	int sig = info->si_signo;
 
+	/*
+	 * On some archs, PREEMPT_RT has to delay sending a signal from a trap
+	 * since it can not enable preemption, and the signal code's spin_locks
+	 * turn into mutexes. Instead, it must set TIF_NOTIFY_RESUME which will
+	 * send the signal on exit of the trap.
+	 */
+#ifdef ARCH_RT_DELAYS_SIGNAL_SEND
+	if (in_atomic()) {
+		struct task_struct *t = current;
+
+		if (WARN_ON_ONCE(t->forced_info.si_signo))
+			return 0;
+
+		if (is_si_special(info)) {
+			WARN_ON_ONCE(info != SEND_SIG_PRIV);
+			t->forced_info.si_signo = info->si_signo;
+			t->forced_info.si_errno = 0;
+			t->forced_info.si_code = SI_KERNEL;
+			t->forced_info.si_pid = 0;
+			t->forced_info.si_uid = 0;
+		} else {
+			t->forced_info = *info;
+		}
+
+		set_tsk_thread_flag(t, TIF_NOTIFY_RESUME);
+		return 0;
+	}
+#endif
 	spin_lock_irqsave(&t->sighand->siglock, flags);
 	action = &t->sighand->action[sig-1];
 	ignored = action->sa.sa_handler == SIG_IGN;
@ kernel/signal.c:1898 @ EXPORT_SYMBOL(kill_pid);
  */
 struct sigqueue *sigqueue_alloc(void)
 {
-	struct sigqueue *q = __sigqueue_alloc(-1, current, GFP_KERNEL, 0);
+	/* Preallocated sigqueue objects always from the slabcache ! */
+	struct sigqueue *q = __sigqueue_do_alloc(-1, current, GFP_KERNEL, 0, 1);
 
 	if (q)
 		q->flags |= SIGQUEUE_PREALLOC;
@ kernel/signal.c:2285 @ static void ptrace_stop(int exit_code, int why, int clear_code, kernel_siginfo_t
 		if (gstop_done && ptrace_reparented(current))
 			do_notify_parent_cldstop(current, false, why);
 
-		/*
-		 * Don't want to allow preemption here, because
-		 * sys_ptrace() needs this task to be inactive.
-		 *
-		 * XXX: implement read_unlock_no_resched().
-		 */
-		preempt_disable();
 		read_unlock(&tasklist_lock);
 		cgroup_enter_frozen();
-		preempt_enable_no_resched();
 		freezable_schedule();
 		cgroup_leave_frozen(true);
 	} else {
@ kernel/smp.c:453 @ void flush_smp_call_function_from_idle(void)
 
 	local_irq_save(flags);
 	flush_smp_call_function_queue(true);
-	if (local_softirq_pending())
-		do_softirq();
+
+	if (local_softirq_pending()) {
+
+		if (!IS_ENABLED(CONFIG_PREEMPT_RT)) {
+			do_softirq();
+		} else {
+			struct task_struct *ksoftirqd = this_cpu_ksoftirqd();
+
+			if (ksoftirqd && ksoftirqd->state != TASK_RUNNING)
+				wake_up_process(ksoftirqd);
+		}
+	}
 
 	local_irq_restore(flags);
 }
@ kernel/softirq.c:16 @
 #include <linux/kernel_stat.h>
 #include <linux/interrupt.h>
 #include <linux/init.h>
+#include <linux/local_lock.h>
 #include <linux/mm.h>
 #include <linux/notifier.h>
 #include <linux/percpu.h>
@ kernel/softirq.c:29 @
 #include <linux/smpboot.h>
 #include <linux/tick.h>
 #include <linux/irq.h>
+#include <linux/wait_bit.h>
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/irq.h>
@ kernel/softirq.c:97 @ static bool ksoftirqd_running(unsigned long pending)
 		!__kthread_should_park(tsk);
 }
 
+#ifdef CONFIG_TRACE_IRQFLAGS
+DEFINE_PER_CPU(int, hardirqs_enabled);
+DEFINE_PER_CPU(int, hardirq_context);
+EXPORT_PER_CPU_SYMBOL_GPL(hardirqs_enabled);
+EXPORT_PER_CPU_SYMBOL_GPL(hardirq_context);
+#endif
+
 /*
- * preempt_count and SOFTIRQ_OFFSET usage:
- * - preempt_count is changed by SOFTIRQ_OFFSET on entering or leaving
- *   softirq processing.
- * - preempt_count is changed by SOFTIRQ_DISABLE_OFFSET (= 2 * SOFTIRQ_OFFSET)
+ * SOFTIRQ_OFFSET usage:
+ *
+ * On !RT kernels 'count' is the preempt counter, on RT kernels this applies
+ * to a per CPU counter and to task::softirqs_disabled_cnt.
+ *
+ * - count is changed by SOFTIRQ_OFFSET on entering or leaving softirq
+ *   processing.
+ *
+ * - count is changed by SOFTIRQ_DISABLE_OFFSET (= 2 * SOFTIRQ_OFFSET)
  *   on local_bh_disable or local_bh_enable.
+ *
  * This lets us distinguish between whether we are currently processing
  * softirq and whether we just have bh disabled.
  */
+#ifdef CONFIG_PREEMPT_RT
 
 /*
- * This one is for softirq.c-internal use,
- * where hardirqs are disabled legitimately:
+ * RT accounts for BH disabled sections in task::softirqs_disabled_cnt and
+ * also in per CPU softirq_ctrl::cnt. This is necessary to allow tasks in a
+ * softirq disabled section to be preempted.
+ *
+ * The per task counter is used for softirq_count(), in_softirq() and
+ * in_serving_softirqs() because these counts are only valid when the task
+ * holding softirq_ctrl::lock is running.
+ *
+ * The per CPU counter prevents pointless wakeups of ksoftirqd in case that
+ * the task which is in a softirq disabled section is preempted or blocks.
  */
-#ifdef CONFIG_TRACE_IRQFLAGS
+struct softirq_ctrl {
+	local_lock_t	lock;
+	int		cnt;
+};
 
-DEFINE_PER_CPU(int, hardirqs_enabled);
-DEFINE_PER_CPU(int, hardirq_context);
-EXPORT_PER_CPU_SYMBOL_GPL(hardirqs_enabled);
-EXPORT_PER_CPU_SYMBOL_GPL(hardirq_context);
+static DEFINE_PER_CPU(struct softirq_ctrl, softirq_ctrl) = {
+	.lock	= INIT_LOCAL_LOCK(softirq_ctrl.lock),
+};
+
+/**
+ * local_bh_blocked() - Check for idle whether BH processing is blocked
+ *
+ * Returns false if the per CPU softirq::cnt is 0 otherwise true.
+ *
+ * This is invoked from the idle task to guard against false positive
+ * softirq pending warnings, which would happen when the task which holds
+ * softirq_ctrl::lock was the only running task on the CPU and blocks on
+ * some other lock.
+ */
+bool local_bh_blocked(void)
+{
+	return __this_cpu_read(softirq_ctrl.cnt) != 0;
+}
+
+void __local_bh_disable_ip(unsigned long ip, unsigned int cnt)
+{
+	unsigned long flags;
+	int newcnt;
+
+	WARN_ON_ONCE(in_hardirq());
+
+	/* First entry of a task into a BH disabled section? */
+	if (!current->softirq_disable_cnt) {
+		if (preemptible()) {
+			local_lock(&softirq_ctrl.lock);
+			/* Required to meet the RCU bottomhalf requirements. */
+			rcu_read_lock();
+		} else {
+			DEBUG_LOCKS_WARN_ON(this_cpu_read(softirq_ctrl.cnt));
+		}
+	}
+
+	/*
+	 * Track the per CPU softirq disabled state. On RT this is per CPU
+	 * state to allow preemption of bottom half disabled sections.
+	 */
+	newcnt = __this_cpu_add_return(softirq_ctrl.cnt, cnt);
+	/*
+	 * Reflect the result in the task state to prevent recursion on the
+	 * local lock and to make softirq_count() & al work.
+	 */
+	current->softirq_disable_cnt = newcnt;
+
+	if (IS_ENABLED(CONFIG_TRACE_IRQFLAGS) && newcnt == cnt) {
+		raw_local_irq_save(flags);
+		lockdep_softirqs_off(ip);
+		raw_local_irq_restore(flags);
+	}
+}
+EXPORT_SYMBOL(__local_bh_disable_ip);
+
+static void __local_bh_enable(unsigned int cnt, bool unlock)
+{
+	unsigned long flags;
+	int newcnt;
+
+	DEBUG_LOCKS_WARN_ON(current->softirq_disable_cnt !=
+			    this_cpu_read(softirq_ctrl.cnt));
+
+	if (IS_ENABLED(CONFIG_TRACE_IRQFLAGS) && softirq_count() == cnt) {
+		raw_local_irq_save(flags);
+		lockdep_softirqs_on(_RET_IP_);
+		raw_local_irq_restore(flags);
+	}
+
+	newcnt = __this_cpu_sub_return(softirq_ctrl.cnt, cnt);
+	current->softirq_disable_cnt = newcnt;
+
+	if (!newcnt && unlock) {
+		rcu_read_unlock();
+		local_unlock(&softirq_ctrl.lock);
+	}
+}
+
+void __local_bh_enable_ip(unsigned long ip, unsigned int cnt)
+{
+	bool preempt_on = preemptible();
+	unsigned long flags;
+	u32 pending;
+	int curcnt;
+
+	WARN_ON_ONCE(in_irq());
+	lockdep_assert_irqs_enabled();
+
+	local_irq_save(flags);
+	curcnt = __this_cpu_read(softirq_ctrl.cnt);
+
+	/*
+	 * If this is not reenabling soft interrupts, no point in trying to
+	 * run pending ones.
+	 */
+	if (curcnt != cnt)
+		goto out;
+
+	pending = local_softirq_pending();
+	if (!pending || ksoftirqd_running(pending))
+		goto out;
+
+	/*
+	 * If this was called from non preemptible context, wake up the
+	 * softirq daemon.
+	 */
+	if (!preempt_on) {
+		wakeup_softirqd();
+		goto out;
+	}
+
+	/*
+	 * Adjust softirq count to SOFTIRQ_OFFSET which makes
+	 * in_serving_softirq() become true.
+	 */
+	cnt = SOFTIRQ_OFFSET;
+	__local_bh_enable(cnt, false);
+	__do_softirq();
+
+out:
+	__local_bh_enable(cnt, preempt_on);
+	local_irq_restore(flags);
+}
+EXPORT_SYMBOL(__local_bh_enable_ip);
+
+/*
+ * Invoked from ksoftirqd_run() outside of the interrupt disabled section
+ * to acquire the per CPU local lock for reentrancy protection.
+ */
+static inline void ksoftirqd_run_begin(void)
+{
+	__local_bh_disable_ip(_RET_IP_, SOFTIRQ_OFFSET);
+	local_irq_disable();
+}
+
+/* Counterpart to ksoftirqd_run_begin() */
+static inline void ksoftirqd_run_end(void)
+{
+	__local_bh_enable(SOFTIRQ_OFFSET, true);
+	WARN_ON_ONCE(in_interrupt());
+	local_irq_enable();
+}
+
+static inline void softirq_handle_begin(void) { }
+static inline void softirq_handle_end(void) { }
 
+static inline bool should_wake_ksoftirqd(void)
+{
+	return !this_cpu_read(softirq_ctrl.cnt);
+}
+
+static inline void invoke_softirq(void)
+{
+	if (should_wake_ksoftirqd())
+		wakeup_softirqd();
+}
+
+#else /* CONFIG_PREEMPT_RT */
+
+/*
+ * This one is for softirq.c-internal use, where hardirqs are disabled
+ * legitimately:
+ */
+#ifdef CONFIG_TRACE_IRQFLAGS
 void __local_bh_disable_ip(unsigned long ip, unsigned int cnt)
 {
 	unsigned long flags;
@ kernel/softirq.c:393 @ void __local_bh_enable_ip(unsigned long ip, unsigned int cnt)
 }
 EXPORT_SYMBOL(__local_bh_enable_ip);
 
+static inline void softirq_handle_begin(void)
+{
+	__local_bh_disable_ip(_RET_IP_, SOFTIRQ_OFFSET);
+}
+
+static inline void softirq_handle_end(void)
+{
+	__local_bh_enable(SOFTIRQ_OFFSET);
+	WARN_ON_ONCE(in_interrupt());
+}
+
+static inline void ksoftirqd_run_begin(void)
+{
+	local_irq_disable();
+}
+
+static inline void ksoftirqd_run_end(void)
+{
+	local_irq_enable();
+}
+
+static inline bool should_wake_ksoftirqd(void)
+{
+	return true;
+}
+
+static inline void invoke_softirq(void)
+{
+	if (ksoftirqd_running(local_softirq_pending()))
+		return;
+
+	if (!force_irqthreads) {
+#ifdef CONFIG_HAVE_IRQ_EXIT_ON_IRQ_STACK
+		/*
+		 * We can safely execute softirq on the current stack if
+		 * it is the irq stack, because it should be near empty
+		 * at this stage.
+		 */
+		__do_softirq();
+#else
+		/*
+		 * Otherwise, irq_exit() is called on the task stack that can
+		 * be potentially deep already. So call softirq in its own stack
+		 * to prevent from any overrun.
+		 */
+		do_softirq_own_stack();
+#endif
+	} else {
+		wakeup_softirqd();
+	}
+}
+
+asmlinkage __visible void do_softirq(void)
+{
+	__u32 pending;
+	unsigned long flags;
+
+	if (in_interrupt())
+		return;
+
+	local_irq_save(flags);
+
+	pending = local_softirq_pending();
+
+	if (pending && !ksoftirqd_running(pending))
+		do_softirq_own_stack();
+
+	local_irq_restore(flags);
+}
+
+#endif /* !CONFIG_PREEMPT_RT */
+
 /*
  * We restart softirq processing for at most MAX_SOFTIRQ_RESTART times,
  * but break the loop if need_resched() is set or after 2 ms.
@ kernel/softirq.c:532 @ asmlinkage __visible void __softirq_entry __do_softirq(void)
 	current->flags &= ~PF_MEMALLOC;
 
 	pending = local_softirq_pending();
-	account_irq_enter_time(current);
 
-	__local_bh_disable_ip(_RET_IP_, SOFTIRQ_OFFSET);
+	softirq_handle_begin();
 	in_hardirq = lockdep_softirq_start();
+	account_softirq_enter(current);
 
 restart:
 	/* Reset the pending bitmask before enabling irqs */
@ kernel/softirq.c:569 @ asmlinkage __visible void __softirq_entry __do_softirq(void)
 		pending >>= softirq_bit;
 	}
 
-	if (__this_cpu_read(ksoftirqd) == current)
+	if (!IS_ENABLED(CONFIG_PREEMPT_RT) &&
+	    __this_cpu_read(ksoftirqd) == current)
 		rcu_softirq_qs();
+
 	local_irq_disable();
 
 	pending = local_softirq_pending();
@ kernel/softirq.c:584 @ asmlinkage __visible void __softirq_entry __do_softirq(void)
 		wakeup_softirqd();
 	}
 
+	account_softirq_exit(current);
 	lockdep_softirq_end(in_hardirq);
-	account_irq_exit_time(current);
-	__local_bh_enable(SOFTIRQ_OFFSET);
-	WARN_ON_ONCE(in_interrupt());
+	softirq_handle_end();
 	current_restore_flags(old_flags, PF_MEMALLOC);
 }
 
-asmlinkage __visible void do_softirq(void)
-{
-	__u32 pending;
-	unsigned long flags;
-
-	if (in_interrupt())
-		return;
-
-	local_irq_save(flags);
-
-	pending = local_softirq_pending();
-
-	if (pending && !ksoftirqd_running(pending))
-		do_softirq_own_stack();
-
-	local_irq_restore(flags);
-}
-
 /**
  * irq_enter_rcu - Enter an interrupt context with RCU watching
  */
 void irq_enter_rcu(void)
 {
-	if (is_idle_task(current) && !in_interrupt()) {
-		/*
-		 * Prevent raise_softirq from needlessly waking up ksoftirqd
-		 * here, as softirq will be serviced on return from interrupt.
-		 */
-		local_bh_disable();
+	__irq_enter_raw();
+
+	if (is_idle_task(current) && (irq_count() == HARDIRQ_OFFSET))
 		tick_irq_enter();
-		_local_bh_enable();
-	}
-	__irq_enter();
+
+	account_hardirq_enter(current);
 }
 
 /**
@ kernel/softirq.c:612 @ void irq_enter(void)
 	irq_enter_rcu();
 }
 
-static inline void invoke_softirq(void)
-{
-	if (ksoftirqd_running(local_softirq_pending()))
-		return;
-
-	if (!force_irqthreads) {
-#ifdef CONFIG_HAVE_IRQ_EXIT_ON_IRQ_STACK
-		/*
-		 * We can safely execute softirq on the current stack if
-		 * it is the irq stack, because it should be near empty
-		 * at this stage.
-		 */
-		__do_softirq();
-#else
-		/*
-		 * Otherwise, irq_exit() is called on the task stack that can
-		 * be potentially deep already. So call softirq in its own stack
-		 * to prevent from any overrun.
-		 */
-		do_softirq_own_stack();
-#endif
-	} else {
-		wakeup_softirqd();
-	}
-}
-
 static inline void tick_irq_exit(void)
 {
 #ifdef CONFIG_NO_HZ_COMMON
@ kernel/softirq.c:632 @ static inline void __irq_exit_rcu(void)
 #else
 	lockdep_assert_irqs_disabled();
 #endif
-	account_irq_exit_time(current);
+	account_hardirq_exit(current);
 	preempt_count_sub(HARDIRQ_OFFSET);
 	if (!in_interrupt() && local_softirq_pending())
 		invoke_softirq();
@ kernel/softirq.c:681 @ inline void raise_softirq_irqoff(unsigned int nr)
 	 * Otherwise we wake up ksoftirqd to make sure we
 	 * schedule the softirq soon.
 	 */
-	if (!in_interrupt())
+	if (!in_interrupt() && should_wake_ksoftirqd())
 		wakeup_softirqd();
 }
 
@ kernel/softirq.c:747 @ void __tasklet_hi_schedule(struct tasklet_struct *t)
 }
 EXPORT_SYMBOL(__tasklet_hi_schedule);
 
+static inline bool tasklet_clear_sched(struct tasklet_struct *t)
+{
+	if (test_and_clear_bit(TASKLET_STATE_SCHED, &t->state)) {
+		wake_up_var(&t->state);
+		return true;
+	}
+
+	return false;
+}
+
 static void tasklet_action_common(struct softirq_action *a,
 				  struct tasklet_head *tl_head,
 				  unsigned int softirq_nr)
@ kernel/softirq.c:776 @ static void tasklet_action_common(struct softirq_action *a,
 
 		if (tasklet_trylock(t)) {
 			if (!atomic_read(&t->count)) {
-				if (!test_and_clear_bit(TASKLET_STATE_SCHED,
-							&t->state))
+				if (!tasklet_clear_sched(t))
 					BUG();
 				if (t->use_callback)
 					t->callback(t);
@ kernel/softirq.c:831 @ void tasklet_init(struct tasklet_struct *t,
 }
 EXPORT_SYMBOL(tasklet_init);
 
+#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT)
+/*
+ * Do not use in new code. Waiting for tasklets from atomic contexts is
+ * error prone and should be avoided.
+ */
+void tasklet_unlock_spin_wait(struct tasklet_struct *t)
+{
+	while (test_bit(TASKLET_STATE_RUN, &(t)->state)) {
+		if (IS_ENABLED(CONFIG_PREEMPT_RT)) {
+			/*
+			 * Prevent a live lock when current preempted soft
+			 * interrupt processing or prevents ksoftirqd from
+			 * running. If the tasklet runs on a different CPU
+			 * then this has no effect other than doing the BH
+			 * disable/enable dance for nothing.
+			 */
+			local_bh_disable();
+			local_bh_enable();
+		} else {
+			cpu_relax();
+		}
+	}
+}
+EXPORT_SYMBOL(tasklet_unlock_spin_wait);
+#endif
+
 void tasklet_kill(struct tasklet_struct *t)
 {
 	if (in_interrupt())
 		pr_notice("Attempt to kill tasklet from interrupt\n");
 
-	while (test_and_set_bit(TASKLET_STATE_SCHED, &t->state)) {
-		do {
-			yield();
-		} while (test_bit(TASKLET_STATE_SCHED, &t->state));
-	}
+	while (test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
+		wait_var_event(&t->state, !test_bit(TASKLET_STATE_SCHED, &t->state));
+
 	tasklet_unlock_wait(t);
-	clear_bit(TASKLET_STATE_SCHED, &t->state);
+	tasklet_clear_sched(t);
 }
 EXPORT_SYMBOL(tasklet_kill);
 
+#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT)
+void tasklet_unlock(struct tasklet_struct *t)
+{
+	smp_mb__before_atomic();
+	clear_bit(TASKLET_STATE_RUN, &t->state);
+	smp_mb__after_atomic();
+	wake_up_var(&t->state);
+}
+EXPORT_SYMBOL_GPL(tasklet_unlock);
+
+void tasklet_unlock_wait(struct tasklet_struct *t)
+{
+	wait_var_event(&t->state, !test_bit(TASKLET_STATE_RUN, &t->state));
+}
+EXPORT_SYMBOL_GPL(tasklet_unlock_wait);
+#endif
+
 void __init softirq_init(void)
 {
 	int cpu;
@ kernel/softirq.c:909 @ static int ksoftirqd_should_run(unsigned int cpu)
 
 static void run_ksoftirqd(unsigned int cpu)
 {
-	local_irq_disable();
+	ksoftirqd_run_begin();
 	if (local_softirq_pending()) {
 		/*
 		 * We can safely run softirq on inline stack, as we are not deep
 		 * in the task stack here.
 		 */
 		__do_softirq();
-		local_irq_enable();
+		ksoftirqd_run_end();
 		cond_resched();
 		return;
 	}
-	local_irq_enable();
+	ksoftirqd_run_end();
 }
 
 #ifdef CONFIG_HOTPLUG_CPU
@ kernel/stop_machine.c:45 @ struct cpu_stopper {
 	struct list_head	works;		/* list of pending works */
 
 	struct cpu_stop_work	stop_work;	/* for stop_cpus */
+	unsigned long		caller;
+	cpu_stop_fn_t		fn;
 };
 
 static DEFINE_PER_CPU(struct cpu_stopper, cpu_stopper);
 static bool stop_machine_initialized = false;
 
+void print_stop_info(const char *log_lvl, struct task_struct *task)
+{
+	struct cpu_stopper *stopper = this_cpu_ptr(&cpu_stopper);
+
+	if (task != stopper->thread)
+		return;
+
+	printk("%sStopper: %pS <- %pS\n", log_lvl, stopper->fn, (void *)stopper->caller);
+}
+
 /* static data for stop_cpus */
 static DEFINE_MUTEX(stop_cpus_mutex);
 static bool stop_cpus_in_progress;
@ kernel/stop_machine.c:138 @ static bool cpu_stop_queue_work(unsigned int cpu, struct cpu_stop_work *work)
 int stop_one_cpu(unsigned int cpu, cpu_stop_fn_t fn, void *arg)
 {
 	struct cpu_stop_done done;
-	struct cpu_stop_work work = { .fn = fn, .arg = arg, .done = &done };
+	struct cpu_stop_work work = { .fn = fn, .arg = arg, .done = &done, .caller = _RET_IP_ };
 
 	cpu_stop_init_done(&done, 1);
 	if (!cpu_stop_queue_work(cpu, &work))
@ kernel/stop_machine.c:346 @ int stop_two_cpus(unsigned int cpu1, unsigned int cpu2, cpu_stop_fn_t fn, void *
 	work1 = work2 = (struct cpu_stop_work){
 		.fn = multi_cpu_stop,
 		.arg = &msdata,
-		.done = &done
+		.done = &done,
+		.caller = _RET_IP_,
 	};
 
 	cpu_stop_init_done(&done, 2);
@ kernel/stop_machine.c:383 @ int stop_two_cpus(unsigned int cpu1, unsigned int cpu2, cpu_stop_fn_t fn, void *
 bool stop_one_cpu_nowait(unsigned int cpu, cpu_stop_fn_t fn, void *arg,
 			struct cpu_stop_work *work_buf)
 {
-	*work_buf = (struct cpu_stop_work){ .fn = fn, .arg = arg, };
+	*work_buf = (struct cpu_stop_work){ .fn = fn, .arg = arg, .caller = _RET_IP_, };
 	return cpu_stop_queue_work(cpu, work_buf);
 }
 
@ kernel/stop_machine.c:503 @ static void cpu_stopper_thread(unsigned int cpu)
 		int ret;
 
 		/* cpu stop callbacks must not sleep, make in_atomic() == T */
+		stopper->caller = work->caller;
+		stopper->fn = fn;
 		preempt_count_inc();
 		ret = fn(arg);
 		if (done) {
@ kernel/stop_machine.c:513 @ static void cpu_stopper_thread(unsigned int cpu)
 			cpu_stop_signal_done(done);
 		}
 		preempt_count_dec();
+		stopper->fn = NULL;
+		stopper->caller = 0;
 		WARN_ONCE(preempt_count(),
 			  "cpu_stop: %ps(%p) leaked preempt count\n", fn, arg);
 		goto repeat;
@ kernel/time/hrtimer.c:2055 @ SYSCALL_DEFINE2(nanosleep_time32, struct old_timespec32 __user *, rqtp,
 }
 #endif
 
+#ifdef CONFIG_PREEMPT_RT
+/*
+ * Sleep for 1 ms in hope whoever holds what we want will let it go.
+ */
+void cpu_chill(void)
+{
+	unsigned int freeze_flag = current->flags & PF_NOFREEZE;
+	struct task_struct *self = current;
+	ktime_t chill_time;
+
+	raw_spin_lock_irq(&self->pi_lock);
+	self->saved_state = self->state;
+	__set_current_state_no_track(TASK_UNINTERRUPTIBLE);
+	raw_spin_unlock_irq(&self->pi_lock);
+
+	chill_time = ktime_set(0, NSEC_PER_MSEC);
+
+	current->flags |= PF_NOFREEZE;
+	schedule_hrtimeout(&chill_time, HRTIMER_MODE_REL_HARD);
+	if (!freeze_flag)
+		current->flags &= ~PF_NOFREEZE;
+
+	raw_spin_lock_irq(&self->pi_lock);
+	__set_current_state_no_track(self->saved_state);
+	self->saved_state = TASK_RUNNING;
+	raw_spin_unlock_irq(&self->pi_lock);
+}
+EXPORT_SYMBOL(cpu_chill);
+#endif
+
 /*
  * Functions related to boot-time initialization:
  */
@ kernel/time/tick-sched.c:928 @ static bool can_stop_idle_tick(int cpu, struct tick_sched *ts)
 	if (unlikely(local_softirq_pending())) {
 		static int ratelimit;
 
-		if (ratelimit < 10 &&
+		if (ratelimit < 10 && !local_bh_blocked() &&
 		    (local_softirq_pending() & SOFTIRQ_STOP_IDLE_MASK)) {
 			pr_warn("NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #%02x!!!\n",
 				(unsigned int) local_softirq_pending());
@ kernel/time/timer.c:1290 @ static void del_timer_wait_running(struct timer_list *timer)
 	u32 tf;
 
 	tf = READ_ONCE(timer->flags);
-	if (!(tf & TIMER_MIGRATING)) {
+	if (!(tf & (TIMER_MIGRATING | TIMER_IRQSAFE))) {
 		struct timer_base *base = get_timer_base(tf);
 
 		/*
@ kernel/time/timer.c:1374 @ int del_timer_sync(struct timer_list *timer)
 	 */
 	WARN_ON(in_irq() && !(timer->flags & TIMER_IRQSAFE));
 
+	/*
+	 * Must be able to sleep on PREEMPT_RT because of the slowpath in
+	 * del_timer_wait_running().
+	 */
+	if (IS_ENABLED(CONFIG_PREEMPT_RT) && !(timer->flags & TIMER_IRQSAFE))
+		lockdep_assert_preemption_enabled();
+
 	do {
 		ret = try_to_del_timer_sync(timer);
 
@ kernel/trace/blktrace.c:75 @ static void trace_note(struct blk_trace *bt, pid_t pid, int action,
 	struct blk_io_trace *t;
 	struct ring_buffer_event *event = NULL;
 	struct trace_buffer *buffer = NULL;
-	int pc = 0;
+	unsigned int trace_ctx = 0;
 	int cpu = smp_processor_id();
 	bool blk_tracer = blk_tracer_enabled;
 	ssize_t cgid_len = cgid ? sizeof(cgid) : 0;
 
 	if (blk_tracer) {
 		buffer = blk_tr->array_buffer.buffer;
-		pc = preempt_count();
+		trace_ctx = tracing_gen_ctx_flags(0);
 		event = trace_buffer_lock_reserve(buffer, TRACE_BLK,
 						  sizeof(*t) + len + cgid_len,
-						  0, pc);
+						  trace_ctx);
 		if (!event)
 			return;
 		t = ring_buffer_event_data(event);
@ kernel/trace/blktrace.c:110 @ static void trace_note(struct blk_trace *bt, pid_t pid, int action,
 		memcpy((void *) t + sizeof(*t) + cgid_len, data, len);
 
 		if (blk_tracer)
-			trace_buffer_unlock_commit(blk_tr, buffer, event, 0, pc);
+			trace_buffer_unlock_commit(blk_tr, buffer, event, trace_ctx);
 	}
 }
 
@ kernel/trace/blktrace.c:225 @ static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes,
 	struct blk_io_trace *t;
 	unsigned long flags = 0;
 	unsigned long *sequence;
+	unsigned int trace_ctx = 0;
 	pid_t pid;
-	int cpu, pc = 0;
+	int cpu;
 	bool blk_tracer = blk_tracer_enabled;
 	ssize_t cgid_len = cgid ? sizeof(cgid) : 0;
 
@ kernel/trace/blktrace.c:256 @ static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes,
 		tracing_record_cmdline(current);
 
 		buffer = blk_tr->array_buffer.buffer;
-		pc = preempt_count();
+		trace_ctx = tracing_gen_ctx_flags(0);
 		event = trace_buffer_lock_reserve(buffer, TRACE_BLK,
 						  sizeof(*t) + pdu_len + cgid_len,
-						  0, pc);
+						  trace_ctx);
 		if (!event)
 			return;
 		t = ring_buffer_event_data(event);
@ kernel/trace/blktrace.c:305 @ static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes,
 			memcpy((void *)t + sizeof(*t) + cgid_len, pdu_data, pdu_len);
 
 		if (blk_tracer) {
-			trace_buffer_unlock_commit(blk_tr, buffer, event, 0, pc);
+			trace_buffer_unlock_commit(blk_tr, buffer, event, trace_ctx);
 			return;
 		}
 	}
@ kernel/trace/trace.c:179 @ static union trace_eval_map_item *trace_eval_maps;
 int tracing_set_tracer(struct trace_array *tr, const char *buf);
 static void ftrace_trace_userstack(struct trace_array *tr,
 				   struct trace_buffer *buffer,
-				   unsigned long flags, int pc);
+				   unsigned int trace_ctx);
 
 #define MAX_TRACER_SIZE		100
 static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata;
@ kernel/trace/trace.c:908 @ static inline void trace_access_lock_init(void)
 
 #ifdef CONFIG_STACKTRACE
 static void __ftrace_trace_stack(struct trace_buffer *buffer,
-				 unsigned long flags,
-				 int skip, int pc, struct pt_regs *regs);
+				 unsigned int trace_ctx,
+				 int skip, struct pt_regs *regs);
 static inline void ftrace_trace_stack(struct trace_array *tr,
 				      struct trace_buffer *buffer,
-				      unsigned long flags,
-				      int skip, int pc, struct pt_regs *regs);
+				      unsigned int trace_ctx,
+				      int skip, struct pt_regs *regs);
 
 #else
 static inline void __ftrace_trace_stack(struct trace_buffer *buffer,
-					unsigned long flags,
-					int skip, int pc, struct pt_regs *regs)
+					unsigned int trace_ctx,
+					int skip, struct pt_regs *regs)
 {
 }
 static inline void ftrace_trace_stack(struct trace_array *tr,
 				      struct trace_buffer *buffer,
-				      unsigned long flags,
-				      int skip, int pc, struct pt_regs *regs)
+				      unsigned long trace_ctx,
+				      int skip, struct pt_regs *regs)
 {
 }
 
@ kernel/trace/trace.c:932 @ static inline void ftrace_trace_stack(struct trace_array *tr,
 
 static __always_inline void
 trace_event_setup(struct ring_buffer_event *event,
-		  int type, unsigned long flags, int pc)
+		  int type, unsigned int trace_ctx)
 {
 	struct trace_entry *ent = ring_buffer_event_data(event);
 
-	tracing_generic_entry_update(ent, type, flags, pc);
+	tracing_generic_entry_update(ent, type, trace_ctx);
 }
 
 static __always_inline struct ring_buffer_event *
 __trace_buffer_lock_reserve(struct trace_buffer *buffer,
 			  int type,
 			  unsigned long len,
-			  unsigned long flags, int pc)
+			  unsigned int trace_ctx)
 {
 	struct ring_buffer_event *event;
 
 	event = ring_buffer_lock_reserve(buffer, len);
 	if (event != NULL)
-		trace_event_setup(event, type, flags, pc);
+		trace_event_setup(event, type, trace_ctx);
 
 	return event;
 }
@ kernel/trace/trace.c:1010 @ int __trace_puts(unsigned long ip, const char *str, int size)
 	struct ring_buffer_event *event;
 	struct trace_buffer *buffer;
 	struct print_entry *entry;
-	unsigned long irq_flags;
+	unsigned int trace_ctx;
 	int alloc;
-	int pc;
 
 	if (!(global_trace.trace_flags & TRACE_ITER_PRINTK))
 		return 0;
 
-	pc = preempt_count();
-
 	if (unlikely(tracing_selftest_running || tracing_disabled))
 		return 0;
 
 	alloc = sizeof(*entry) + size + 2; /* possible \n added */
 
-	local_save_flags(irq_flags);
+	trace_ctx = tracing_gen_ctx();
 	buffer = global_trace.array_buffer.buffer;
 	ring_buffer_nest_start(buffer);
-	event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, 
-					    irq_flags, pc);
+	event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc,
+					    trace_ctx);
 	if (!event) {
 		size = 0;
 		goto out;
@ kernel/trace/trace.c:1044 @ int __trace_puts(unsigned long ip, const char *str, int size)
 		entry->buf[size] = '\0';
 
 	__buffer_unlock_commit(buffer, event);
-	ftrace_trace_stack(&global_trace, buffer, irq_flags, 4, pc, NULL);
+	ftrace_trace_stack(&global_trace, buffer, trace_ctx, 4, NULL);
  out:
 	ring_buffer_nest_end(buffer);
 	return size;
@ kernel/trace/trace.c:1061 @ int __trace_bputs(unsigned long ip, const char *str)
 	struct ring_buffer_event *event;
 	struct trace_buffer *buffer;
 	struct bputs_entry *entry;
-	unsigned long irq_flags;
+	unsigned int trace_ctx;
 	int size = sizeof(struct bputs_entry);
 	int ret = 0;
-	int pc;
 
 	if (!(global_trace.trace_flags & TRACE_ITER_PRINTK))
 		return 0;
 
-	pc = preempt_count();
-
 	if (unlikely(tracing_selftest_running || tracing_disabled))
 		return 0;
 
-	local_save_flags(irq_flags);
+	trace_ctx = tracing_gen_ctx();
 	buffer = global_trace.array_buffer.buffer;
 
 	ring_buffer_nest_start(buffer);
 	event = __trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size,
-					    irq_flags, pc);
+					    trace_ctx);
 	if (!event)
 		goto out;
 
@ kernel/trace/trace.c:1085 @ int __trace_bputs(unsigned long ip, const char *str)
 	entry->str			= str;
 
 	__buffer_unlock_commit(buffer, event);
-	ftrace_trace_stack(&global_trace, buffer, irq_flags, 4, pc, NULL);
+	ftrace_trace_stack(&global_trace, buffer, trace_ctx, 4, NULL);
 
 	ret = 1;
  out:
@ kernel/trace/trace.c:2589 @ enum print_line_t trace_handle_return(struct trace_seq *s)
 }
 EXPORT_SYMBOL_GPL(trace_handle_return);
 
-void
-tracing_generic_entry_update(struct trace_entry *entry, unsigned short type,
-			     unsigned long flags, int pc)
+static unsigned short migration_disable_value(void)
 {
-	struct task_struct *tsk = current;
-
-	entry->preempt_count		= pc & 0xff;
-	entry->pid			= (tsk) ? tsk->pid : 0;
-	entry->type			= type;
-	entry->flags =
-#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
-		(irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) |
+#if defined(CONFIG_SMP) && defined(CONFIG_PREEMPT_RT)
+	return current->migration_disabled;
 #else
-		TRACE_FLAG_IRQS_NOSUPPORT |
+	return 0;
+#endif
+}
+
+unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status)
+{
+	unsigned int trace_flags = irqs_status;
+	unsigned int pc;
+
+	pc = preempt_count();
+
+	if (pc & NMI_MASK)
+		trace_flags |= TRACE_FLAG_NMI;
+	if (pc & HARDIRQ_MASK)
+		trace_flags |= TRACE_FLAG_HARDIRQ;
+	if (in_serving_softirq())
+		trace_flags |= TRACE_FLAG_SOFTIRQ;
+
+	if (tif_need_resched())
+		trace_flags |= TRACE_FLAG_NEED_RESCHED;
+	if (test_preempt_need_resched())
+		trace_flags |= TRACE_FLAG_PREEMPT_RESCHED;
+
+#ifdef CONFIG_PREEMPT_LAZY
+	if (need_resched_lazy())
+		trace_flags |= TRACE_FLAG_NEED_RESCHED_LAZY;
 #endif
-		((pc & NMI_MASK    ) ? TRACE_FLAG_NMI     : 0) |
-		((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) |
-		((pc & SOFTIRQ_OFFSET) ? TRACE_FLAG_SOFTIRQ : 0) |
-		(tif_need_resched() ? TRACE_FLAG_NEED_RESCHED : 0) |
-		(test_preempt_need_resched() ? TRACE_FLAG_PREEMPT_RESCHED : 0);
+
+	return (pc & 0xff) |
+		(migration_disable_value() & 0xff) << 8 |
+		(preempt_lazy_count() & 0xff) << 16 |
+		(trace_flags << 24);
 }
-EXPORT_SYMBOL_GPL(tracing_generic_entry_update);
 
 struct ring_buffer_event *
 trace_buffer_lock_reserve(struct trace_buffer *buffer,
 			  int type,
 			  unsigned long len,
-			  unsigned long flags, int pc)
+			  unsigned int trace_ctx)
 {
-	return __trace_buffer_lock_reserve(buffer, type, len, flags, pc);
+	return __trace_buffer_lock_reserve(buffer, type, len, trace_ctx);
 }
 
 DEFINE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
@ kernel/trace/trace.c:2754 @ struct ring_buffer_event *
 trace_event_buffer_lock_reserve(struct trace_buffer **current_rb,
 			  struct trace_event_file *trace_file,
 			  int type, unsigned long len,
-			  unsigned long flags, int pc)
+			  unsigned int trace_ctx)
 {
 	struct ring_buffer_event *entry;
 	int val;
@ kernel/trace/trace.c:2767 @ trace_event_buffer_lock_reserve(struct trace_buffer **current_rb,
 		/* Try to use the per cpu buffer first */
 		val = this_cpu_inc_return(trace_buffered_event_cnt);
 		if ((len < (PAGE_SIZE - sizeof(*entry) - sizeof(entry->array[0]))) && val == 1) {
-			trace_event_setup(entry, type, flags, pc);
+			trace_event_setup(entry, type, trace_ctx);
 			entry->array[0] = len;
 			return entry;
 		}
@ kernel/trace/trace.c:2775 @ trace_event_buffer_lock_reserve(struct trace_buffer **current_rb,
 	}
 
 	entry = __trace_buffer_lock_reserve(*current_rb,
-					    type, len, flags, pc);
+					    type, len, trace_ctx);
 	/*
 	 * If tracing is off, but we have triggers enabled
 	 * we still need to look at the event data. Use the temp_buffer
@ kernel/trace/trace.c:2784 @ trace_event_buffer_lock_reserve(struct trace_buffer **current_rb,
 	 */
 	if (!entry && trace_file->flags & EVENT_FILE_FL_TRIGGER_COND) {
 		*current_rb = temp_buffer;
-		entry = __trace_buffer_lock_reserve(*current_rb,
-						    type, len, flags, pc);
+		entry = __trace_buffer_lock_reserve(*current_rb, type, len,
+						    trace_ctx);
 	}
 	return entry;
 }
@ kernel/trace/trace.c:2871 @ void trace_event_buffer_commit(struct trace_event_buffer *fbuffer)
 		ftrace_exports(fbuffer->event, TRACE_EXPORT_EVENT);
 	event_trigger_unlock_commit_regs(fbuffer->trace_file, fbuffer->buffer,
 				    fbuffer->event, fbuffer->entry,
-				    fbuffer->flags, fbuffer->pc, fbuffer->regs);
+				    fbuffer->trace_ctx, fbuffer->regs);
 }
 EXPORT_SYMBOL_GPL(trace_event_buffer_commit);
 
@ kernel/trace/trace.c:2887 @ EXPORT_SYMBOL_GPL(trace_event_buffer_commit);
 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
 				     struct trace_buffer *buffer,
 				     struct ring_buffer_event *event,
-				     unsigned long flags, int pc,
+				     unsigned int trace_ctx,
 				     struct pt_regs *regs)
 {
 	__buffer_unlock_commit(buffer, event);
@ kernel/trace/trace.c:2898 @ void trace_buffer_unlock_commit_regs(struct trace_array *tr,
 	 * and mmiotrace, but that's ok if they lose a function or
 	 * two. They are not that meaningful.
 	 */
-	ftrace_trace_stack(tr, buffer, flags, regs ? 0 : STACK_SKIP, pc, regs);
-	ftrace_trace_userstack(tr, buffer, flags, pc);
+	ftrace_trace_stack(tr, buffer, trace_ctx, regs ? 0 : STACK_SKIP, regs);
+	ftrace_trace_userstack(tr, buffer, trace_ctx);
 }
 
 /*
@ kernel/trace/trace.c:2913 @ trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
 }
 
 void
-trace_function(struct trace_array *tr,
-	       unsigned long ip, unsigned long parent_ip, unsigned long flags,
-	       int pc)
+trace_function(struct trace_array *tr, unsigned long ip, unsigned long
+	       parent_ip, unsigned int trace_ctx)
 {
 	struct trace_event_call *call = &event_function;
 	struct trace_buffer *buffer = tr->array_buffer.buffer;
@ kernel/trace/trace.c:2922 @ trace_function(struct trace_array *tr,
 	struct ftrace_entry *entry;
 
 	event = __trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry),
-					    flags, pc);
+					    trace_ctx);
 	if (!event)
 		return;
 	entry	= ring_buffer_event_data(event);
@ kernel/trace/trace.c:2956 @ static DEFINE_PER_CPU(struct ftrace_stacks, ftrace_stacks);
 static DEFINE_PER_CPU(int, ftrace_stack_reserve);
 
 static void __ftrace_trace_stack(struct trace_buffer *buffer,
-				 unsigned long flags,
-				 int skip, int pc, struct pt_regs *regs)
+				 unsigned int trace_ctx,
+				 int skip, struct pt_regs *regs)
 {
 	struct trace_event_call *call = &event_kernel_stack;
 	struct ring_buffer_event *event;
@ kernel/trace/trace.c:3005 @ static void __ftrace_trace_stack(struct trace_buffer *buffer,
 	size = nr_entries * sizeof(unsigned long);
 	event = __trace_buffer_lock_reserve(buffer, TRACE_STACK,
 				    (sizeof(*entry) - sizeof(entry->caller)) + size,
-				    flags, pc);
+				    trace_ctx);
 	if (!event)
 		goto out;
 	entry = ring_buffer_event_data(event);
@ kernel/trace/trace.c:3026 @ static void __ftrace_trace_stack(struct trace_buffer *buffer,
 
 static inline void ftrace_trace_stack(struct trace_array *tr,
 				      struct trace_buffer *buffer,
-				      unsigned long flags,
-				      int skip, int pc, struct pt_regs *regs)
+				      unsigned int trace_ctx,
+				      int skip, struct pt_regs *regs)
 {
 	if (!(tr->trace_flags & TRACE_ITER_STACKTRACE))
 		return;
 
-	__ftrace_trace_stack(buffer, flags, skip, pc, regs);
+	__ftrace_trace_stack(buffer, trace_ctx, skip, regs);
 }
 
-void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
-		   int pc)
+void __trace_stack(struct trace_array *tr, unsigned int trace_ctx,
+		   int skip)
 {
 	struct trace_buffer *buffer = tr->array_buffer.buffer;
 
 	if (rcu_is_watching()) {
-		__ftrace_trace_stack(buffer, flags, skip, pc, NULL);
+		__ftrace_trace_stack(buffer, trace_ctx, skip, NULL);
 		return;
 	}
 
@ kernel/trace/trace.c:3055 @ void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
 		return;
 
 	rcu_irq_enter_irqson();
-	__ftrace_trace_stack(buffer, flags, skip, pc, NULL);
+	__ftrace_trace_stack(buffer, trace_ctx, skip, NULL);
 	rcu_irq_exit_irqson();
 }
 
@ kernel/trace/trace.c:3065 @ void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
  */
 void trace_dump_stack(int skip)
 {
-	unsigned long flags;
-
 	if (tracing_disabled || tracing_selftest_running)
 		return;
 
-	local_save_flags(flags);
-
 #ifndef CONFIG_UNWINDER_ORC
 	/* Skip 1 to skip this function. */
 	skip++;
 #endif
 	__ftrace_trace_stack(global_trace.array_buffer.buffer,
-			     flags, skip, preempt_count(), NULL);
+			     tracing_gen_ctx(), skip, NULL);
 }
 EXPORT_SYMBOL_GPL(trace_dump_stack);
 
@ kernel/trace/trace.c:3082 @ static DEFINE_PER_CPU(int, user_stack_count);
 
 static void
 ftrace_trace_userstack(struct trace_array *tr,
-		       struct trace_buffer *buffer, unsigned long flags, int pc)
+		       struct trace_buffer *buffer, unsigned int trace_ctx)
 {
 	struct trace_event_call *call = &event_user_stack;
 	struct ring_buffer_event *event;
@ kernel/trace/trace.c:3109 @ ftrace_trace_userstack(struct trace_array *tr,
 	__this_cpu_inc(user_stack_count);
 
 	event = __trace_buffer_lock_reserve(buffer, TRACE_USER_STACK,
-					    sizeof(*entry), flags, pc);
+					    sizeof(*entry), trace_ctx);
 	if (!event)
 		goto out_drop_count;
 	entry	= ring_buffer_event_data(event);
@ kernel/trace/trace.c:3129 @ ftrace_trace_userstack(struct trace_array *tr,
 #else /* CONFIG_USER_STACKTRACE_SUPPORT */
 static void ftrace_trace_userstack(struct trace_array *tr,
 				   struct trace_buffer *buffer,
-				   unsigned long flags, int pc)
+				   unsigned int trace_ctx)
 {
 }
 #endif /* !CONFIG_USER_STACKTRACE_SUPPORT */
@ kernel/trace/trace.c:3259 @ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
 	struct trace_buffer *buffer;
 	struct trace_array *tr = &global_trace;
 	struct bprint_entry *entry;
-	unsigned long flags;
+	unsigned int trace_ctx;
 	char *tbuffer;
-	int len = 0, size, pc;
+	int len = 0, size;
 
 	if (unlikely(tracing_selftest_running || tracing_disabled))
 		return 0;
@ kernel/trace/trace.c:3269 @ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
 	/* Don't pollute graph traces with trace_vprintk internals */
 	pause_graph_tracing();
 
-	pc = preempt_count();
+	trace_ctx = tracing_gen_ctx();
 	preempt_disable_notrace();
 
 	tbuffer = get_trace_buf();
@ kernel/trace/trace.c:3283 @ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
 	if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0)
 		goto out_put;
 
-	local_save_flags(flags);
 	size = sizeof(*entry) + sizeof(u32) * len;
 	buffer = tr->array_buffer.buffer;
 	ring_buffer_nest_start(buffer);
 	event = __trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size,
-					    flags, pc);
+					    trace_ctx);
 	if (!event)
 		goto out;
 	entry = ring_buffer_event_data(event);
@ kernel/trace/trace.c:3297 @ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
 	memcpy(entry->buf, tbuffer, sizeof(u32) * len);
 	if (!call_filter_check_discard(call, entry, buffer, event)) {
 		__buffer_unlock_commit(buffer, event);
-		ftrace_trace_stack(tr, buffer, flags, 6, pc, NULL);
+		ftrace_trace_stack(tr, buffer, trace_ctx, 6, NULL);
 	}
 
 out:
@ kernel/trace/trace.c:3320 @ __trace_array_vprintk(struct trace_buffer *buffer,
 {
 	struct trace_event_call *call = &event_print;
 	struct ring_buffer_event *event;
-	int len = 0, size, pc;
+	int len = 0, size;
 	struct print_entry *entry;
-	unsigned long flags;
+	unsigned int trace_ctx;
 	char *tbuffer;
 
 	if (tracing_disabled || tracing_selftest_running)
@ kernel/trace/trace.c:3331 @ __trace_array_vprintk(struct trace_buffer *buffer,
 	/* Don't pollute graph traces with trace_vprintk internals */
 	pause_graph_tracing();
 
-	pc = preempt_count();
+	trace_ctx = tracing_gen_ctx();
 	preempt_disable_notrace();
 
 
@ kernel/trace/trace.c:3343 @ __trace_array_vprintk(struct trace_buffer *buffer,
 
 	len = vscnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args);
 
-	local_save_flags(flags);
 	size = sizeof(*entry) + len + 1;
 	ring_buffer_nest_start(buffer);
 	event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, size,
-					    flags, pc);
+					    trace_ctx);
 	if (!event)
 		goto out;
 	entry = ring_buffer_event_data(event);
@ kernel/trace/trace.c:3355 @ __trace_array_vprintk(struct trace_buffer *buffer,
 	memcpy(&entry->buf, tbuffer, len + 1);
 	if (!call_filter_check_discard(call, entry, buffer, event)) {
 		__buffer_unlock_commit(buffer, event);
-		ftrace_trace_stack(&global_trace, buffer, flags, 6, pc, NULL);
+		ftrace_trace_stack(&global_trace, buffer, trace_ctx, 6, NULL);
 	}
 
 out:
@ kernel/trace/trace.c:3821 @ unsigned long trace_total_entries(struct trace_array *tr)
 
 static void print_lat_help_header(struct seq_file *m)
 {
-	seq_puts(m, "#                    _------=> CPU#            \n"
-		    "#                   / _-----=> irqs-off        \n"
-		    "#                  | / _----=> need-resched    \n"
-		    "#                  || / _---=> hardirq/softirq \n"
-		    "#                  ||| / _--=> preempt-depth   \n"
-		    "#                  |||| /     delay            \n"
-		    "#  cmd     pid     ||||| time  |   caller      \n"
-		    "#     \\   /        |||||  \\    |   /         \n");
+	seq_puts(m, "#                    _--------=> CPU#            \n"
+		    "#                   / _-------=> irqs-off        \n"
+		    "#                  | / _------=> need-resched    \n"
+		    "#                  || / _-----=> need-resched-lazy\n"
+		    "#                  ||| / _----=> hardirq/softirq \n"
+		    "#                  |||| / _---=> preempt-depth   \n"
+		    "#                  ||||| / _--=> preempt-lazy-depth\n"
+		    "#                  |||||| / _-=> migrate-disable \n"
+		    "#                  ||||||| /     delay           \n"
+		    "#  cmd     pid     |||||||| time  |   caller     \n"
+		    "#     \\   /        ||||||||  \\    |    /       \n");
 }
 
 static void print_event_info(struct array_buffer *buf, struct seq_file *m)
@ kernel/trace/trace.c:3865 @ static void print_func_help_header_irq(struct array_buffer *buf, struct seq_file
 
 	print_event_info(buf, m);
 
-	seq_printf(m, "#                            %.*s  _-----=> irqs-off\n", prec, space);
-	seq_printf(m, "#                            %.*s / _----=> need-resched\n", prec, space);
-	seq_printf(m, "#                            %.*s| / _---=> hardirq/softirq\n", prec, space);
-	seq_printf(m, "#                            %.*s|| / _--=> preempt-depth\n", prec, space);
-	seq_printf(m, "#                            %.*s||| /     delay\n", prec, space);
-	seq_printf(m, "#           TASK-PID  %.*s CPU#  ||||   TIMESTAMP  FUNCTION\n", prec, "     TGID   ");
-	seq_printf(m, "#              | |    %.*s   |   ||||      |         |\n", prec, "       |    ");
+	seq_printf(m, "#                            %.*s  _-------=> irqs-off\n", prec, space);
+	seq_printf(m, "#                            %.*s / _------=> need-resched\n", prec, space);
+	seq_printf(m, "#                            %.*s| / _-----=> need-resched-lazy\n", prec, space);
+	seq_printf(m, "#                            %.*s|| / _----=> hardirq/softirq\n", prec, space);
+	seq_printf(m, "#                            %.*s||| / _---=> preempt-depth\n", prec, space);
+	seq_printf(m, "#                            %.*s|||| / _--=> preempt-lazy-depth\n", prec, space);
+	seq_printf(m, "#                            %.*s||||| / _-=> migrate-disable\n", prec, space);
+	seq_printf(m, "#                            %.*s|||||| /     delay\n", prec, space);
+	seq_printf(m, "#           TASK-PID  %.*s CPU#  |||||||  TIMESTAMP  FUNCTION\n", prec, "     TGID   ");
+	seq_printf(m, "#              | |    %.*s   |   |||||||      |         |\n", prec, "       |    ");
 }
 
 void
@ kernel/trace/trace.c:6667 @ tracing_mark_write(struct file *filp, const char __user *ubuf,
 	enum event_trigger_type tt = ETT_NONE;
 	struct trace_buffer *buffer;
 	struct print_entry *entry;
-	unsigned long irq_flags;
 	ssize_t written;
 	int size;
 	int len;
@ kernel/trace/trace.c:6686 @ tracing_mark_write(struct file *filp, const char __user *ubuf,
 
 	BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE);
 
-	local_save_flags(irq_flags);
 	size = sizeof(*entry) + cnt + 2; /* add '\0' and possible '\n' */
 
 	/* If less than "<faulted>", then make sure we can still add that */
@ kernel/trace/trace.c:6694 @ tracing_mark_write(struct file *filp, const char __user *ubuf,
 
 	buffer = tr->array_buffer.buffer;
 	event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, size,
-					    irq_flags, preempt_count());
+					    tracing_gen_ctx());
 	if (unlikely(!event))
 		/* Ring buffer disabled, return as if not open for write */
 		return -EBADF;
@ kernel/trace/trace.c:6746 @ tracing_mark_raw_write(struct file *filp, const char __user *ubuf,
 	struct ring_buffer_event *event;
 	struct trace_buffer *buffer;
 	struct raw_data_entry *entry;
-	unsigned long irq_flags;
 	ssize_t written;
 	int size;
 	int len;
@ kernel/trace/trace.c:6767 @ tracing_mark_raw_write(struct file *filp, const char __user *ubuf,
 
 	BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE);
 
-	local_save_flags(irq_flags);
 	size = sizeof(*entry) + cnt;
 	if (cnt < FAULT_SIZE_ID)
 		size += FAULT_SIZE_ID - cnt;
 
 	buffer = tr->array_buffer.buffer;
 	event = __trace_buffer_lock_reserve(buffer, TRACE_RAW_DATA, size,
-					    irq_flags, preempt_count());
+					    tracing_gen_ctx());
 	if (!event)
 		/* Ring buffer disabled, return as if not open for write */
 		return -EBADF;
@ kernel/trace/trace.c:9326 @ void ftrace_dump(enum ftrace_dump_mode oops_dump_mode)
 	tracing_off();
 
 	local_irq_save(flags);
-	printk_nmi_direct_enter();
 
 	/* Simulate the iterator */
 	trace_init_global_iter(&iter);
@ kernel/trace/trace.c:9405 @ void ftrace_dump(enum ftrace_dump_mode oops_dump_mode)
 		atomic_dec(&per_cpu_ptr(iter.array_buffer->data, cpu)->disabled);
 	}
 	atomic_dec(&dump_running);
-	printk_nmi_direct_exit();
 	local_irq_restore(flags);
 }
 EXPORT_SYMBOL_GPL(ftrace_dump);
@ kernel/trace/trace.h:139 @ struct kretprobe_trace_entry_head {
 	unsigned long		ret_ip;
 };
 
-/*
- * trace_flag_type is an enumeration that holds different
- * states when a trace occurs. These are:
- *  IRQS_OFF		- interrupts were disabled
- *  IRQS_NOSUPPORT	- arch does not support irqs_disabled_flags
- *  NEED_RESCHED	- reschedule is requested
- *  HARDIRQ		- inside an interrupt handler
- *  SOFTIRQ		- inside a softirq handler
- */
-enum trace_flag_type {
-	TRACE_FLAG_IRQS_OFF		= 0x01,
-	TRACE_FLAG_IRQS_NOSUPPORT	= 0x02,
-	TRACE_FLAG_NEED_RESCHED		= 0x04,
-	TRACE_FLAG_HARDIRQ		= 0x08,
-	TRACE_FLAG_SOFTIRQ		= 0x10,
-	TRACE_FLAG_PREEMPT_RESCHED	= 0x20,
-	TRACE_FLAG_NMI			= 0x40,
-};
-
 #define TRACE_BUF_SIZE		1024
 
 struct trace_array;
@ kernel/trace/trace.h:729 @ struct ring_buffer_event *
 trace_buffer_lock_reserve(struct trace_buffer *buffer,
 			  int type,
 			  unsigned long len,
-			  unsigned long flags,
-			  int pc);
+			  unsigned int trace_ctx);
 
 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
 						struct trace_array_cpu *data);
@ kernel/trace/trace.h:754 @ unsigned long trace_total_entries(struct trace_array *tr);
 void trace_function(struct trace_array *tr,
 		    unsigned long ip,
 		    unsigned long parent_ip,
-		    unsigned long flags, int pc);
+		    unsigned int trace_ctx);
 void trace_graph_function(struct trace_array *tr,
 		    unsigned long ip,
 		    unsigned long parent_ip,
-		    unsigned long flags, int pc);
+		    unsigned int trace_ctx);
 void trace_latency_header(struct seq_file *m);
 void trace_default_header(struct seq_file *m);
 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
@ kernel/trace/trace.h:826 @ static inline void latency_fsnotify(struct trace_array *tr) { }
 #endif
 
 #ifdef CONFIG_STACKTRACE
-void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
-		   int pc);
+void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, int skip);
 #else
-static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
-				 int skip, int pc)
+static inline void __trace_stack(struct trace_array *tr, unsigned int trace_ctx,
+				 int skip)
 {
 }
 #endif /* CONFIG_STACKTRACE */
@ kernel/trace/trace.h:969 @ extern void graph_trace_open(struct trace_iterator *iter);
 extern void graph_trace_close(struct trace_iterator *iter);
 extern int __trace_graph_entry(struct trace_array *tr,
 			       struct ftrace_graph_ent *trace,
-			       unsigned long flags, int pc);
+			       unsigned int trace_ctx);
 extern void __trace_graph_return(struct trace_array *tr,
 				 struct ftrace_graph_ret *trace,
-				 unsigned long flags, int pc);
+				 unsigned int trace_ctx);
 
 #ifdef CONFIG_DYNAMIC_FTRACE
 extern struct ftrace_hash __rcu *ftrace_graph_hash;
@ kernel/trace/trace.h:1435 @ extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
 				     struct trace_buffer *buffer,
 				     struct ring_buffer_event *event,
-				     unsigned long flags, int pc,
+				     unsigned int trcace_ctx,
 				     struct pt_regs *regs);
 
 static inline void trace_buffer_unlock_commit(struct trace_array *tr,
 					      struct trace_buffer *buffer,
 					      struct ring_buffer_event *event,
-					      unsigned long flags, int pc)
+					      unsigned int trace_ctx)
 {
-	trace_buffer_unlock_commit_regs(tr, buffer, event, flags, pc, NULL);
+	trace_buffer_unlock_commit_regs(tr, buffer, event, trace_ctx, NULL);
 }
 
 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
@ kernel/trace/trace.h:1516 @ __event_trigger_test_discard(struct trace_event_file *file,
  * @buffer: The ring buffer that the event is being written to
  * @event: The event meta data in the ring buffer
  * @entry: The event itself
- * @irq_flags: The state of the interrupts at the start of the event
- * @pc: The state of the preempt count at the start of the event.
+ * @trace_ctx: The tracing context flags.
  *
  * This is a helper function to handle triggers that require data
  * from the event itself. It also tests the event against filters and
@ kernel/trace/trace.h:1526 @ static inline void
 event_trigger_unlock_commit(struct trace_event_file *file,
 			    struct trace_buffer *buffer,
 			    struct ring_buffer_event *event,
-			    void *entry, unsigned long irq_flags, int pc)
+			    void *entry, unsigned int trace_ctx)
 {
 	enum event_trigger_type tt = ETT_NONE;
 
 	if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
-		trace_buffer_unlock_commit(file->tr, buffer, event, irq_flags, pc);
+		trace_buffer_unlock_commit(file->tr, buffer, event, trace_ctx);
 
 	if (tt)
 		event_triggers_post_call(file, tt);
@ kernel/trace/trace.h:1543 @ event_trigger_unlock_commit(struct trace_event_file *file,
  * @buffer: The ring buffer that the event is being written to
  * @event: The event meta data in the ring buffer
  * @entry: The event itself
- * @irq_flags: The state of the interrupts at the start of the event
- * @pc: The state of the preempt count at the start of the event.
+ * @trace_ctx: The tracing context flags.
  *
  * This is a helper function to handle triggers that require data
  * from the event itself. It also tests the event against filters and
@ kernel/trace/trace.h:1556 @ static inline void
 event_trigger_unlock_commit_regs(struct trace_event_file *file,
 				 struct trace_buffer *buffer,
 				 struct ring_buffer_event *event,
-				 void *entry, unsigned long irq_flags, int pc,
+				 void *entry, unsigned int trace_ctx,
 				 struct pt_regs *regs)
 {
 	enum event_trigger_type tt = ETT_NONE;
 
 	if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
 		trace_buffer_unlock_commit_regs(file->tr, buffer, event,
-						irq_flags, pc, regs);
+						trace_ctx, regs);
 
 	if (tt)
 		event_triggers_post_call(file, tt);
@ kernel/trace/trace_branch.c:40 @ probe_likely_condition(struct ftrace_likely_data *f, int val, int expect)
 	struct ring_buffer_event *event;
 	struct trace_branch *entry;
 	unsigned long flags;
-	int pc;
+	unsigned int trace_ctx;
 	const char *p;
 
 	if (current->trace_recursion & TRACE_BRANCH_BIT)
@ kernel/trace/trace_branch.c:62 @ probe_likely_condition(struct ftrace_likely_data *f, int val, int expect)
 	if (atomic_read(&data->disabled))
 		goto out;
 
-	pc = preempt_count();
+	trace_ctx = tracing_gen_ctx_flags(flags);
 	buffer = tr->array_buffer.buffer;
 	event = trace_buffer_lock_reserve(buffer, TRACE_BRANCH,
-					  sizeof(*entry), flags, pc);
+					  sizeof(*entry), trace_ctx);
 	if (!event)
 		goto out;
 
@ kernel/trace/trace_event_perf.c:424 @ NOKPROBE_SYMBOL(perf_trace_buf_alloc);
 void perf_trace_buf_update(void *record, u16 type)
 {
 	struct trace_entry *entry = record;
-	int pc = preempt_count();
-	unsigned long flags;
 
-	local_save_flags(flags);
-	tracing_generic_entry_update(entry, type, flags, pc);
+	tracing_generic_entry_update(entry, type, tracing_gen_ctx());
 }
 NOKPROBE_SYMBOL(perf_trace_buf_update);
 
@ kernel/trace/trace_events.c:186 @ static int trace_define_common_fields(void)
 	__common_field(unsigned char, flags);
 	__common_field(unsigned char, preempt_count);
 	__common_field(int, pid);
+	__common_field(unsigned char, migrate_disable);
+	__common_field(unsigned char, preempt_lazy_count);
 
 	return ret;
 }
@ kernel/trace/trace_events.c:263 @ void *trace_event_buffer_reserve(struct trace_event_buffer *fbuffer,
 	    trace_event_ignore_this_pid(trace_file))
 		return NULL;
 
-	local_save_flags(fbuffer->flags);
-	fbuffer->pc = preempt_count();
 	/*
 	 * If CONFIG_PREEMPTION is enabled, then the tracepoint itself disables
 	 * preemption (adding one to the preempt_count). Since we are
 	 * interested in the preempt_count at the time the tracepoint was
 	 * hit, we need to subtract one to offset the increment.
 	 */
-	if (IS_ENABLED(CONFIG_PREEMPTION))
-		fbuffer->pc--;
+	fbuffer->trace_ctx = tracing_gen_ctx_dec();
 	fbuffer->trace_file = trace_file;
 
 	fbuffer->event =
 		trace_event_buffer_lock_reserve(&fbuffer->buffer, trace_file,
 						event_call->event.type, len,
-						fbuffer->flags, fbuffer->pc);
+						fbuffer->trace_ctx);
 	if (!fbuffer->event)
 		return NULL;
 
@ kernel/trace/trace_events.c:3691 @ function_test_events_call(unsigned long ip, unsigned long parent_ip,
 	struct trace_buffer *buffer;
 	struct ring_buffer_event *event;
 	struct ftrace_entry *entry;
-	unsigned long flags;
+	unsigned int trace_ctx;
 	long disabled;
 	int cpu;
-	int pc;
 
-	pc = preempt_count();
+	trace_ctx = tracing_gen_ctx();
 	preempt_disable_notrace();
 	cpu = raw_smp_processor_id();
 	disabled = atomic_inc_return(&per_cpu(ftrace_test_event_disable, cpu));
@ kernel/trace/trace_events.c:3703 @ function_test_events_call(unsigned long ip, unsigned long parent_ip,
 	if (disabled != 1)
 		goto out;
 
-	local_save_flags(flags);
-
 	event = trace_event_buffer_lock_reserve(&buffer, &event_trace_file,
 						TRACE_FN, sizeof(*entry),
-						flags, pc);
+						trace_ctx);
 	if (!event)
 		goto out;
 	entry	= ring_buffer_event_data(event);
@ kernel/trace/trace_events.c:3713 @ function_test_events_call(unsigned long ip, unsigned long parent_ip,
 	entry->parent_ip		= parent_ip;
 
 	event_trigger_unlock_commit(&event_trace_file, buffer, event,
-				    entry, flags, pc);
+				    entry, trace_ctx);
  out:
 	atomic_dec(&per_cpu(ftrace_test_event_disable, cpu));
 	preempt_enable_notrace();
@ kernel/trace/trace_events_inject.c:195 @ static void *trace_alloc_entry(struct trace_event_call *call, int *size)
 static int parse_entry(char *str, struct trace_event_call *call, void **pentry)
 {
 	struct ftrace_event_field *field;
-	unsigned long irq_flags;
 	void *entry = NULL;
 	int entry_size;
 	u64 val = 0;
@ kernel/trace/trace_events_inject.c:205 @ static int parse_entry(char *str, struct trace_event_call *call, void **pentry)
 	if (!entry)
 		return -ENOMEM;
 
-	local_save_flags(irq_flags);
-	tracing_generic_entry_update(entry, call->event.type, irq_flags,
-				     preempt_count());
+	tracing_generic_entry_update(entry, call->event.type,
+				     tracing_gen_ctx());
 
 	while ((len = parse_field(str, call, &field, &val)) > 0) {
 		if (is_function_field(field))
@ kernel/trace/trace_functions.c:136 @ function_trace_call(unsigned long ip, unsigned long parent_ip,
 {
 	struct trace_array *tr = op->private;
 	struct trace_array_cpu *data;
-	unsigned long flags;
+	unsigned int trace_ctx;
 	int bit;
 	int cpu;
-	int pc;
 
 	if (unlikely(!tr->function_enabled))
 		return;
 
-	pc = preempt_count();
+	trace_ctx = tracing_gen_ctx();
 	preempt_disable_notrace();
 
 	bit = trace_test_and_set_recursion(TRACE_FTRACE_START);
@ kernel/trace/trace_functions.c:152 @ function_trace_call(unsigned long ip, unsigned long parent_ip,
 
 	cpu = smp_processor_id();
 	data = per_cpu_ptr(tr->array_buffer.data, cpu);
-	if (!atomic_read(&data->disabled)) {
-		local_save_flags(flags);
-		trace_function(tr, ip, parent_ip, flags, pc);
-	}
+	if (!atomic_read(&data->disabled))
+		trace_function(tr, ip, parent_ip, trace_ctx);
+
 	trace_clear_recursion(bit);
 
  out:
@ kernel/trace/trace_functions.c:188 @ function_stack_trace_call(unsigned long ip, unsigned long parent_ip,
 	unsigned long flags;
 	long disabled;
 	int cpu;
-	int pc;
+	unsigned int trace_ctx;
 
 	if (unlikely(!tr->function_enabled))
 		return;
@ kernel/trace/trace_functions.c:203 @ function_stack_trace_call(unsigned long ip, unsigned long parent_ip,
 	disabled = atomic_inc_return(&data->disabled);
 
 	if (likely(disabled == 1)) {
-		pc = preempt_count();
-		trace_function(tr, ip, parent_ip, flags, pc);
-		__trace_stack(tr, flags, STACK_SKIP, pc);
+		trace_ctx = tracing_gen_ctx_flags(flags);
+		trace_function(tr, ip, parent_ip, trace_ctx);
+		__trace_stack(tr, trace_ctx, STACK_SKIP);
 	}
 
 	atomic_dec(&data->disabled);
@ kernel/trace/trace_functions.c:408 @ ftrace_traceoff(unsigned long ip, unsigned long parent_ip,
 
 static __always_inline void trace_stack(struct trace_array *tr)
 {
-	unsigned long flags;
-	int pc;
+	unsigned int trace_ctx;
 
-	local_save_flags(flags);
-	pc = preempt_count();
+	trace_ctx = tracing_gen_ctx();
 
-	__trace_stack(tr, flags, FTRACE_STACK_SKIP, pc);
+	__trace_stack(tr, trace_ctx, FTRACE_STACK_SKIP);
 }
 
 static void
@ kernel/trace/trace_functions_graph.c:99 @ print_graph_duration(struct trace_array *tr, unsigned long long duration,
 
 int __trace_graph_entry(struct trace_array *tr,
 				struct ftrace_graph_ent *trace,
-				unsigned long flags,
-				int pc)
+				unsigned int trace_ctx)
 {
 	struct trace_event_call *call = &event_funcgraph_entry;
 	struct ring_buffer_event *event;
@ kernel/trace/trace_functions_graph.c:107 @ int __trace_graph_entry(struct trace_array *tr,
 	struct ftrace_graph_ent_entry *entry;
 
 	event = trace_buffer_lock_reserve(buffer, TRACE_GRAPH_ENT,
-					  sizeof(*entry), flags, pc);
+					  sizeof(*entry), trace_ctx);
 	if (!event)
 		return 0;
 	entry	= ring_buffer_event_data(event);
@ kernel/trace/trace_functions_graph.c:131 @ int trace_graph_entry(struct ftrace_graph_ent *trace)
 	struct trace_array *tr = graph_array;
 	struct trace_array_cpu *data;
 	unsigned long flags;
+	unsigned int trace_ctx;
 	long disabled;
 	int ret;
 	int cpu;
-	int pc;
 
 	if (trace_recursion_test(TRACE_GRAPH_NOTRACE_BIT))
 		return 0;
@ kernel/trace/trace_functions_graph.c:176 @ int trace_graph_entry(struct ftrace_graph_ent *trace)
 	data = per_cpu_ptr(tr->array_buffer.data, cpu);
 	disabled = atomic_inc_return(&data->disabled);
 	if (likely(disabled == 1)) {
-		pc = preempt_count();
-		ret = __trace_graph_entry(tr, trace, flags, pc);
+		trace_ctx = tracing_gen_ctx_flags(flags);
+		ret = __trace_graph_entry(tr, trace, trace_ctx);
 	} else {
 		ret = 0;
 	}
@ kernel/trace/trace_functions_graph.c:190 @ int trace_graph_entry(struct ftrace_graph_ent *trace)
 
 static void
 __trace_graph_function(struct trace_array *tr,
-		unsigned long ip, unsigned long flags, int pc)
+		unsigned long ip, unsigned int trace_ctx)
 {
 	u64 time = trace_clock_local();
 	struct ftrace_graph_ent ent = {
@ kernel/trace/trace_functions_graph.c:204 @ __trace_graph_function(struct trace_array *tr,
 		.rettime  = time,
 	};
 
-	__trace_graph_entry(tr, &ent, flags, pc);
-	__trace_graph_return(tr, &ret, flags, pc);
+	__trace_graph_entry(tr, &ent, trace_ctx);
+	__trace_graph_return(tr, &ret, trace_ctx);
 }
 
 void
 trace_graph_function(struct trace_array *tr,
 		unsigned long ip, unsigned long parent_ip,
-		unsigned long flags, int pc)
+		unsigned int trace_ctx)
 {
-	__trace_graph_function(tr, ip, flags, pc);
+	__trace_graph_function(tr, ip, trace_ctx);
 }
 
 void __trace_graph_return(struct trace_array *tr,
 				struct ftrace_graph_ret *trace,
-				unsigned long flags,
-				int pc)
+				unsigned int trace_ctx)
 {
 	struct trace_event_call *call = &event_funcgraph_exit;
 	struct ring_buffer_event *event;
@ kernel/trace/trace_functions_graph.c:226 @ void __trace_graph_return(struct trace_array *tr,
 	struct ftrace_graph_ret_entry *entry;
 
 	event = trace_buffer_lock_reserve(buffer, TRACE_GRAPH_RET,
-					  sizeof(*entry), flags, pc);
+					  sizeof(*entry), trace_ctx);
 	if (!event)
 		return;
 	entry	= ring_buffer_event_data(event);
@ kernel/trace/trace_functions_graph.c:240 @ void trace_graph_return(struct ftrace_graph_ret *trace)
 	struct trace_array *tr = graph_array;
 	struct trace_array_cpu *data;
 	unsigned long flags;
+	unsigned int trace_ctx;
 	long disabled;
 	int cpu;
-	int pc;
 
 	ftrace_graph_addr_finish(trace);
 
@ kernel/trace/trace_functions_graph.c:256 @ void trace_graph_return(struct ftrace_graph_ret *trace)
 	data = per_cpu_ptr(tr->array_buffer.data, cpu);
 	disabled = atomic_inc_return(&data->disabled);
 	if (likely(disabled == 1)) {
-		pc = preempt_count();
-		__trace_graph_return(tr, trace, flags, pc);
+		trace_ctx = tracing_gen_ctx_flags(flags);
+		__trace_graph_return(tr, trace, trace_ctx);
 	}
 	atomic_dec(&data->disabled);
 	local_irq_restore(flags);
@ kernel/trace/trace_hwlat.c:111 @ static void trace_hwlat_sample(struct hwlat_sample *sample)
 	struct trace_buffer *buffer = tr->array_buffer.buffer;
 	struct ring_buffer_event *event;
 	struct hwlat_entry *entry;
-	unsigned long flags;
-	int pc;
-
-	pc = preempt_count();
-	local_save_flags(flags);
 
 	event = trace_buffer_lock_reserve(buffer, TRACE_HWLAT, sizeof(*entry),
-					  flags, pc);
+					  tracing_gen_ctx());
 	if (!event)
 		return;
 	entry	= ring_buffer_event_data(event);
@ kernel/trace/trace_irqsoff.c:146 @ irqsoff_tracer_call(unsigned long ip, unsigned long parent_ip,
 	struct trace_array *tr = irqsoff_trace;
 	struct trace_array_cpu *data;
 	unsigned long flags;
+	unsigned int trace_ctx;
 
 	if (!func_prolog_dec(tr, &data, &flags))
 		return;
 
-	trace_function(tr, ip, parent_ip, flags, preempt_count());
+	trace_ctx = tracing_gen_ctx_flags(flags);
+
+	trace_function(tr, ip, parent_ip, trace_ctx);
 
 	atomic_dec(&data->disabled);
 }
@ kernel/trace/trace_irqsoff.c:183 @ static int irqsoff_graph_entry(struct ftrace_graph_ent *trace)
 	struct trace_array *tr = irqsoff_trace;
 	struct trace_array_cpu *data;
 	unsigned long flags;
+	unsigned int trace_ctx;
 	int ret;
-	int pc;
 
 	if (ftrace_graph_ignore_func(trace))
 		return 0;
@ kernel/trace/trace_irqsoff.c:201 @ static int irqsoff_graph_entry(struct ftrace_graph_ent *trace)
 	if (!func_prolog_dec(tr, &data, &flags))
 		return 0;
 
-	pc = preempt_count();
-	ret = __trace_graph_entry(tr, trace, flags, pc);
+	trace_ctx = tracing_gen_ctx_flags(flags);
+	ret = __trace_graph_entry(tr, trace, trace_ctx);
 	atomic_dec(&data->disabled);
 
 	return ret;
@ kernel/trace/trace_irqsoff.c:213 @ static void irqsoff_graph_return(struct ftrace_graph_ret *trace)
 	struct trace_array *tr = irqsoff_trace;
 	struct trace_array_cpu *data;
 	unsigned long flags;
-	int pc;
+	unsigned int trace_ctx;
 
 	ftrace_graph_addr_finish(trace);
 
 	if (!func_prolog_dec(tr, &data, &flags))
 		return;
 
-	pc = preempt_count();
-	__trace_graph_return(tr, trace, flags, pc);
+	trace_ctx = tracing_gen_ctx_flags(flags);
+	__trace_graph_return(tr, trace, trace_ctx);
 	atomic_dec(&data->disabled);
 }
 
@ kernel/trace/trace_irqsoff.c:273 @ static void irqsoff_print_header(struct seq_file *s)
 static void
 __trace_function(struct trace_array *tr,
 		 unsigned long ip, unsigned long parent_ip,
-		 unsigned long flags, int pc)
+		 unsigned int trace_ctx)
 {
 	if (is_graph(tr))
-		trace_graph_function(tr, ip, parent_ip, flags, pc);
+		trace_graph_function(tr, ip, parent_ip, trace_ctx);
 	else
-		trace_function(tr, ip, parent_ip, flags, pc);
+		trace_function(tr, ip, parent_ip, trace_ctx);
 }
 
 #else
@ kernel/trace/trace_irqsoff.c:328 @ check_critical_timing(struct trace_array *tr,
 {
 	u64 T0, T1, delta;
 	unsigned long flags;
-	int pc;
+	unsigned int trace_ctx;
 
 	T0 = data->preempt_timestamp;
 	T1 = ftrace_now(cpu);
 	delta = T1-T0;
 
-	local_save_flags(flags);
-
-	pc = preempt_count();
+	trace_ctx = tracing_gen_ctx();
 
 	if (!report_latency(tr, delta))
 		goto out;
@ kernel/trace/trace_irqsoff.c:345 @ check_critical_timing(struct trace_array *tr,
 	if (!report_latency(tr, delta))
 		goto out_unlock;
 
-	__trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc);
+	__trace_function(tr, CALLER_ADDR0, parent_ip, trace_ctx);
 	/* Skip 5 functions to get to the irq/preempt enable function */
-	__trace_stack(tr, flags, 5, pc);
+	__trace_stack(tr, trace_ctx, 5);
 
 	if (data->critical_sequence != max_sequence)
 		goto out_unlock;
@ kernel/trace/trace_irqsoff.c:367 @ check_critical_timing(struct trace_array *tr,
 out:
 	data->critical_sequence = max_sequence;
 	data->preempt_timestamp = ftrace_now(cpu);
-	__trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc);
+	__trace_function(tr, CALLER_ADDR0, parent_ip, trace_ctx);
 }
 
 static nokprobe_inline void
-start_critical_timing(unsigned long ip, unsigned long parent_ip, int pc)
+start_critical_timing(unsigned long ip, unsigned long parent_ip)
 {
 	int cpu;
 	struct trace_array *tr = irqsoff_trace;
 	struct trace_array_cpu *data;
-	unsigned long flags;
 
 	if (!tracer_enabled || !tracing_is_enabled())
 		return;
@ kernel/trace/trace_irqsoff.c:396 @ start_critical_timing(unsigned long ip, unsigned long parent_ip, int pc)
 	data->preempt_timestamp = ftrace_now(cpu);
 	data->critical_start = parent_ip ? : ip;
 
-	local_save_flags(flags);
-
-	__trace_function(tr, ip, parent_ip, flags, pc);
+	__trace_function(tr, ip, parent_ip, tracing_gen_ctx());
 
 	per_cpu(tracing_cpu, cpu) = 1;
 
@ kernel/trace/trace_irqsoff.c:404 @ start_critical_timing(unsigned long ip, unsigned long parent_ip, int pc)
 }
 
 static nokprobe_inline void
-stop_critical_timing(unsigned long ip, unsigned long parent_ip, int pc)
+stop_critical_timing(unsigned long ip, unsigned long parent_ip)
 {
 	int cpu;
 	struct trace_array *tr = irqsoff_trace;
 	struct trace_array_cpu *data;
-	unsigned long flags;
+	unsigned int trace_ctx;
 
 	cpu = raw_smp_processor_id();
 	/* Always clear the tracing cpu on stopping the trace */
@ kernel/trace/trace_irqsoff.c:429 @ stop_critical_timing(unsigned long ip, unsigned long parent_ip, int pc)
 
 	atomic_inc(&data->disabled);
 
-	local_save_flags(flags);
-	__trace_function(tr, ip, parent_ip, flags, pc);
+	trace_ctx = tracing_gen_ctx();
+	__trace_function(tr, ip, parent_ip, trace_ctx);
 	check_critical_timing(tr, data, parent_ip ? : ip, cpu);
 	data->critical_start = 0;
 	atomic_dec(&data->disabled);
@ kernel/trace/trace_irqsoff.c:439 @ stop_critical_timing(unsigned long ip, unsigned long parent_ip, int pc)
 /* start and stop critical timings used to for stoppage (in idle) */
 void start_critical_timings(void)
 {
-	int pc = preempt_count();
-
-	if (preempt_trace(pc) || irq_trace())
-		start_critical_timing(CALLER_ADDR0, CALLER_ADDR1, pc);
+	if (preempt_trace(preempt_count()) || irq_trace())
+		start_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
 }
 EXPORT_SYMBOL_GPL(start_critical_timings);
 NOKPROBE_SYMBOL(start_critical_timings);
 
 void stop_critical_timings(void)
 {
-	int pc = preempt_count();
-
-	if (preempt_trace(pc) || irq_trace())
-		stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1, pc);
+	if (preempt_trace(preempt_count()) || irq_trace())
+		stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
 }
 EXPORT_SYMBOL_GPL(stop_critical_timings);
 NOKPROBE_SYMBOL(stop_critical_timings);
@ kernel/trace/trace_irqsoff.c:610 @ static void irqsoff_tracer_stop(struct trace_array *tr)
  */
 void tracer_hardirqs_on(unsigned long a0, unsigned long a1)
 {
-	unsigned int pc = preempt_count();
-
-	if (!preempt_trace(pc) && irq_trace())
-		stop_critical_timing(a0, a1, pc);
+	if (!preempt_trace(preempt_count()) && irq_trace())
+		stop_critical_timing(a0, a1);
 }
 NOKPROBE_SYMBOL(tracer_hardirqs_on);
 
 void tracer_hardirqs_off(unsigned long a0, unsigned long a1)
 {
-	unsigned int pc = preempt_count();
-
-	if (!preempt_trace(pc) && irq_trace())
-		start_critical_timing(a0, a1, pc);
+	if (!preempt_trace(preempt_count()) && irq_trace())
+		start_critical_timing(a0, a1);
 }
 NOKPROBE_SYMBOL(tracer_hardirqs_off);
 
@ kernel/trace/trace_irqsoff.c:658 @ static struct tracer irqsoff_tracer __read_mostly =
 #ifdef CONFIG_PREEMPT_TRACER
 void tracer_preempt_on(unsigned long a0, unsigned long a1)
 {
-	int pc = preempt_count();
-
-	if (preempt_trace(pc) && !irq_trace())
-		stop_critical_timing(a0, a1, pc);
+	if (preempt_trace(preempt_count()) && !irq_trace())
+		stop_critical_timing(a0, a1);
 }
 
 void tracer_preempt_off(unsigned long a0, unsigned long a1)
 {
-	int pc = preempt_count();
-
-	if (preempt_trace(pc) && !irq_trace())
-		start_critical_timing(a0, a1, pc);
+	if (preempt_trace(preempt_count()) && !irq_trace())
+		start_critical_timing(a0, a1);
 }
 
 static int preemptoff_tracer_init(struct trace_array *tr)
@ kernel/trace/trace_kprobe.c:1393 @ __kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs,
 	if (trace_trigger_soft_disabled(trace_file))
 		return;
 
-	local_save_flags(fbuffer.flags);
-	fbuffer.pc = preempt_count();
+	fbuffer.trace_ctx = tracing_gen_ctx();
 	fbuffer.trace_file = trace_file;
 
 	dsize = __get_data_size(&tk->tp, regs);
@ kernel/trace/trace_kprobe.c:1402 @ __kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs,
 		trace_event_buffer_lock_reserve(&fbuffer.buffer, trace_file,
 					call->event.type,
 					sizeof(*entry) + tk->tp.size + dsize,
-					fbuffer.flags, fbuffer.pc);
+					fbuffer.trace_ctx);
 	if (!fbuffer.event)
 		return;
 
@ kernel/trace/trace_kprobe.c:1440 @ __kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri,
 	if (trace_trigger_soft_disabled(trace_file))
 		return;
 
-	local_save_flags(fbuffer.flags);
-	fbuffer.pc = preempt_count();
+	fbuffer.trace_ctx = tracing_gen_ctx();
 	fbuffer.trace_file = trace_file;
 
 	dsize = __get_data_size(&tk->tp, regs);
@ kernel/trace/trace_kprobe.c:1448 @ __kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri,
 		trace_event_buffer_lock_reserve(&fbuffer.buffer, trace_file,
 					call->event.type,
 					sizeof(*entry) + tk->tp.size + dsize,
-					fbuffer.flags, fbuffer.pc);
+					fbuffer.trace_ctx);
 	if (!fbuffer.event)
 		return;
 
@ kernel/trace/trace_mmiotrace.c:303 @ static void __trace_mmiotrace_rw(struct trace_array *tr,
 	struct trace_buffer *buffer = tr->array_buffer.buffer;
 	struct ring_buffer_event *event;
 	struct trace_mmiotrace_rw *entry;
-	int pc = preempt_count();
+	unsigned int trace_ctx;
 
+	trace_ctx = tracing_gen_ctx_flags(0);
 	event = trace_buffer_lock_reserve(buffer, TRACE_MMIO_RW,
-					  sizeof(*entry), 0, pc);
+					  sizeof(*entry), trace_ctx);
 	if (!event) {
 		atomic_inc(&dropped_count);
 		return;
@ kernel/trace/trace_mmiotrace.c:316 @ static void __trace_mmiotrace_rw(struct trace_array *tr,
 	entry->rw			= *rw;
 
 	if (!call_filter_check_discard(call, entry, buffer, event))
-		trace_buffer_unlock_commit(tr, buffer, event, 0, pc);
+		trace_buffer_unlock_commit(tr, buffer, event, trace_ctx);
 }
 
 void mmio_trace_rw(struct mmiotrace_rw *rw)
@ kernel/trace/trace_mmiotrace.c:334 @ static void __trace_mmiotrace_map(struct trace_array *tr,
 	struct trace_buffer *buffer = tr->array_buffer.buffer;
 	struct ring_buffer_event *event;
 	struct trace_mmiotrace_map *entry;
-	int pc = preempt_count();
+	unsigned int trace_ctx;
 
+	trace_ctx = tracing_gen_ctx_flags(0);
 	event = trace_buffer_lock_reserve(buffer, TRACE_MMIO_MAP,
-					  sizeof(*entry), 0, pc);
+					  sizeof(*entry), trace_ctx);
 	if (!event) {
 		atomic_inc(&dropped_count);
 		return;
@ kernel/trace/trace_mmiotrace.c:347 @ static void __trace_mmiotrace_map(struct trace_array *tr,
 	entry->map			= *map;
 
 	if (!call_filter_check_discard(call, entry, buffer, event))
-		trace_buffer_unlock_commit(tr, buffer, event, 0, pc);
+		trace_buffer_unlock_commit(tr, buffer, event, trace_ctx);
 }
 
 void mmio_trace_mapping(struct mmiotrace_map *map)
@ kernel/trace/trace_output.c:444 @ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 {
 	char hardsoft_irq;
 	char need_resched;
+	char need_resched_lazy;
 	char irqs_off;
 	int hardirq;
 	int softirq;
@ kernel/trace/trace_output.c:475 @ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 		break;
 	}
 
+	need_resched_lazy =
+		(entry->flags & TRACE_FLAG_NEED_RESCHED_LAZY) ? 'L' : '.';
+
 	hardsoft_irq =
 		(nmi && hardirq)     ? 'Z' :
 		nmi                  ? 'z' :
@ kernel/trace/trace_output.c:486 @ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 		softirq              ? 's' :
 		                       '.' ;
 
-	trace_seq_printf(s, "%c%c%c",
-			 irqs_off, need_resched, hardsoft_irq);
+	trace_seq_printf(s, "%c%c%c%c",
+			 irqs_off, need_resched, need_resched_lazy,
+			 hardsoft_irq);
 
 	if (entry->preempt_count)
 		trace_seq_printf(s, "%x", entry->preempt_count);
 	else
 		trace_seq_putc(s, '.');
 
+	if (entry->preempt_lazy_count)
+		trace_seq_printf(s, "%x", entry->preempt_lazy_count);
+	else
+		trace_seq_putc(s, '.');
+
+	if (entry->migrate_disable)
+		trace_seq_printf(s, "%x", entry->migrate_disable);
+	else
+		trace_seq_putc(s, '.');
+
 	return !trace_seq_has_overflowed(s);
 }
 
@ kernel/trace/trace_sched_wakeup.c:70 @ static bool function_enabled;
 static int
 func_prolog_preempt_disable(struct trace_array *tr,
 			    struct trace_array_cpu **data,
-			    int *pc)
+			    unsigned int *trace_ctx)
 {
 	long disabled;
 	int cpu;
@ kernel/trace/trace_sched_wakeup.c:78 @ func_prolog_preempt_disable(struct trace_array *tr,
 	if (likely(!wakeup_task))
 		return 0;
 
-	*pc = preempt_count();
+	*trace_ctx = tracing_gen_ctx();
 	preempt_disable_notrace();
 
 	cpu = raw_smp_processor_id();
@ kernel/trace/trace_sched_wakeup.c:119 @ static int wakeup_graph_entry(struct ftrace_graph_ent *trace)
 {
 	struct trace_array *tr = wakeup_trace;
 	struct trace_array_cpu *data;
-	unsigned long flags;
-	int pc, ret = 0;
+	unsigned int trace_ctx;
+	int ret = 0;
 
 	if (ftrace_graph_ignore_func(trace))
 		return 0;
@ kernel/trace/trace_sched_wakeup.c:134 @ static int wakeup_graph_entry(struct ftrace_graph_ent *trace)
 	if (ftrace_graph_notrace_addr(trace->func))
 		return 1;
 
-	if (!func_prolog_preempt_disable(tr, &data, &pc))
+	if (!func_prolog_preempt_disable(tr, &data, &trace_ctx))
 		return 0;
 
-	local_save_flags(flags);
-	ret = __trace_graph_entry(tr, trace, flags, pc);
+	ret = __trace_graph_entry(tr, trace, trace_ctx);
 	atomic_dec(&data->disabled);
 	preempt_enable_notrace();
 
@ kernel/trace/trace_sched_wakeup.c:148 @ static void wakeup_graph_return(struct ftrace_graph_ret *trace)
 {
 	struct trace_array *tr = wakeup_trace;
 	struct trace_array_cpu *data;
-	unsigned long flags;
-	int pc;
+	unsigned int trace_ctx;
 
 	ftrace_graph_addr_finish(trace);
 
-	if (!func_prolog_preempt_disable(tr, &data, &pc))
+	if (!func_prolog_preempt_disable(tr, &data, &trace_ctx))
 		return;
 
-	local_save_flags(flags);
-	__trace_graph_return(tr, trace, flags, pc);
+	__trace_graph_return(tr, trace, trace_ctx);
 	atomic_dec(&data->disabled);
 
 	preempt_enable_notrace();
@ kernel/trace/trace_sched_wakeup.c:217 @ wakeup_tracer_call(unsigned long ip, unsigned long parent_ip,
 	struct trace_array *tr = wakeup_trace;
 	struct trace_array_cpu *data;
 	unsigned long flags;
-	int pc;
+	unsigned int trace_ctx;
 
-	if (!func_prolog_preempt_disable(tr, &data, &pc))
+	if (!func_prolog_preempt_disable(tr, &data, &trace_ctx))
 		return;
 
 	local_irq_save(flags);
-	trace_function(tr, ip, parent_ip, flags, pc);
+	trace_function(tr, ip, parent_ip, trace_ctx);
 	local_irq_restore(flags);
 
 	atomic_dec(&data->disabled);
@ kernel/trace/trace_sched_wakeup.c:303 @ static void wakeup_print_header(struct seq_file *s)
 static void
 __trace_function(struct trace_array *tr,
 		 unsigned long ip, unsigned long parent_ip,
-		 unsigned long flags, int pc)
+		 unsigned int trace_ctx)
 {
 	if (is_graph(tr))
-		trace_graph_function(tr, ip, parent_ip, flags, pc);
+		trace_graph_function(tr, ip, parent_ip, trace_ctx);
 	else
-		trace_function(tr, ip, parent_ip, flags, pc);
+		trace_function(tr, ip, parent_ip, trace_ctx);
 }
 
 static int wakeup_flag_changed(struct trace_array *tr, u32 mask, int set)
@ kernel/trace/trace_sched_wakeup.c:375 @ static void
 tracing_sched_switch_trace(struct trace_array *tr,
 			   struct task_struct *prev,
 			   struct task_struct *next,
-			   unsigned long flags, int pc)
+			   unsigned int trace_ctx)
 {
 	struct trace_event_call *call = &event_context_switch;
 	struct trace_buffer *buffer = tr->array_buffer.buffer;
@ kernel/trace/trace_sched_wakeup.c:383 @ tracing_sched_switch_trace(struct trace_array *tr,
 	struct ctx_switch_entry *entry;
 
 	event = trace_buffer_lock_reserve(buffer, TRACE_CTX,
-					  sizeof(*entry), flags, pc);
+					  sizeof(*entry), trace_ctx);
 	if (!event)
 		return;
 	entry	= ring_buffer_event_data(event);
@ kernel/trace/trace_sched_wakeup.c:396 @ tracing_sched_switch_trace(struct trace_array *tr,
 	entry->next_cpu	= task_cpu(next);
 
 	if (!call_filter_check_discard(call, entry, buffer, event))
-		trace_buffer_unlock_commit(tr, buffer, event, flags, pc);
+		trace_buffer_unlock_commit(tr, buffer, event, trace_ctx);
 }
 
 static void
 tracing_sched_wakeup_trace(struct trace_array *tr,
 			   struct task_struct *wakee,
 			   struct task_struct *curr,
-			   unsigned long flags, int pc)
+			   unsigned int trace_ctx)
 {
 	struct trace_event_call *call = &event_wakeup;
 	struct ring_buffer_event *event;
@ kernel/trace/trace_sched_wakeup.c:411 @ tracing_sched_wakeup_trace(struct trace_array *tr,
 	struct trace_buffer *buffer = tr->array_buffer.buffer;
 
 	event = trace_buffer_lock_reserve(buffer, TRACE_WAKE,
-					  sizeof(*entry), flags, pc);
+					  sizeof(*entry), trace_ctx);
 	if (!event)
 		return;
 	entry	= ring_buffer_event_data(event);
@ kernel/trace/trace_sched_wakeup.c:424 @ tracing_sched_wakeup_trace(struct trace_array *tr,
 	entry->next_cpu			= task_cpu(wakee);
 
 	if (!call_filter_check_discard(call, entry, buffer, event))
-		trace_buffer_unlock_commit(tr, buffer, event, flags, pc);
+		trace_buffer_unlock_commit(tr, buffer, event, trace_ctx);
 }
 
 static void notrace
@ kernel/trace/trace_sched_wakeup.c:436 @ probe_wakeup_sched_switch(void *ignore, bool preempt,
 	unsigned long flags;
 	long disabled;
 	int cpu;
-	int pc;
+	unsigned int trace_ctx;
 
 	tracing_record_cmdline(prev);
 
@ kernel/trace/trace_sched_wakeup.c:455 @ probe_wakeup_sched_switch(void *ignore, bool preempt,
 	if (next != wakeup_task)
 		return;
 
-	pc = preempt_count();
-
 	/* disable local data, not wakeup_cpu data */
 	cpu = raw_smp_processor_id();
 	disabled = atomic_inc_return(&per_cpu_ptr(wakeup_trace->array_buffer.data, cpu)->disabled);
@ kernel/trace/trace_sched_wakeup.c:462 @ probe_wakeup_sched_switch(void *ignore, bool preempt,
 		goto out;
 
 	local_irq_save(flags);
+	trace_ctx = tracing_gen_ctx_flags(flags);
+
 	arch_spin_lock(&wakeup_lock);
 
 	/* We could race with grabbing wakeup_lock */
@ kernel/trace/trace_sched_wakeup.c:473 @ probe_wakeup_sched_switch(void *ignore, bool preempt,
 	/* The task we are waiting for is waking up */
 	data = per_cpu_ptr(wakeup_trace->array_buffer.data, wakeup_cpu);
 
-	__trace_function(wakeup_trace, CALLER_ADDR0, CALLER_ADDR1, flags, pc);
-	tracing_sched_switch_trace(wakeup_trace, prev, next, flags, pc);
-	__trace_stack(wakeup_trace, flags, 0, pc);
+	__trace_function(wakeup_trace, CALLER_ADDR0, CALLER_ADDR1, trace_ctx);
+	tracing_sched_switch_trace(wakeup_trace, prev, next, trace_ctx);
+	__trace_stack(wakeup_trace, trace_ctx, 0);
 
 	T0 = data->preempt_timestamp;
 	T1 = ftrace_now(cpu);
@ kernel/trace/trace_sched_wakeup.c:527 @ probe_wakeup(void *ignore, struct task_struct *p)
 {
 	struct trace_array_cpu *data;
 	int cpu = smp_processor_id();
-	unsigned long flags;
 	long disabled;
-	int pc;
+	unsigned int trace_ctx;
 
 	if (likely(!tracer_enabled))
 		return;
@ kernel/trace/trace_sched_wakeup.c:549 @ probe_wakeup(void *ignore, struct task_struct *p)
 	    (!dl_task(p) && (p->prio >= wakeup_prio || p->prio >= current->prio)))
 		return;
 
-	pc = preempt_count();
 	disabled = atomic_inc_return(&per_cpu_ptr(wakeup_trace->array_buffer.data, cpu)->disabled);
 	if (unlikely(disabled != 1))
 		goto out;
 
+	trace_ctx = tracing_gen_ctx();
+
 	/* interrupts should be off from try_to_wake_up */
 	arch_spin_lock(&wakeup_lock);
 
@ kernel/trace/trace_sched_wakeup.c:581 @ probe_wakeup(void *ignore, struct task_struct *p)
 
 	wakeup_task = get_task_struct(p);
 
-	local_save_flags(flags);
-
 	data = per_cpu_ptr(wakeup_trace->array_buffer.data, wakeup_cpu);
 	data->preempt_timestamp = ftrace_now(cpu);
-	tracing_sched_wakeup_trace(wakeup_trace, p, current, flags, pc);
-	__trace_stack(wakeup_trace, flags, 0, pc);
+	tracing_sched_wakeup_trace(wakeup_trace, p, current, trace_ctx);
+	__trace_stack(wakeup_trace, trace_ctx, 0);
 
 	/*
 	 * We must be careful in using CALLER_ADDR2. But since wake_up
 	 * is not called by an assembly function  (where as schedule is)
 	 * it should be safe to use it here.
 	 */
-	__trace_function(wakeup_trace, CALLER_ADDR1, CALLER_ADDR2, flags, pc);
+	__trace_function(wakeup_trace, CALLER_ADDR1, CALLER_ADDR2, trace_ctx);
 
 out_locked:
 	arch_spin_unlock(&wakeup_lock);
@ kernel/trace/trace_syscalls.c:301 @ static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id)
 	struct syscall_metadata *sys_data;
 	struct ring_buffer_event *event;
 	struct trace_buffer *buffer;
-	unsigned long irq_flags;
+	unsigned int trace_ctx;
 	unsigned long args[6];
-	int pc;
 	int syscall_nr;
 	int size;
 
@ kernel/trace/trace_syscalls.c:324 @ static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id)
 
 	size = sizeof(*entry) + sizeof(unsigned long) * sys_data->nb_args;
 
-	local_save_flags(irq_flags);
-	pc = preempt_count();
+	trace_ctx = tracing_gen_ctx();
 
 	buffer = tr->array_buffer.buffer;
 	event = trace_buffer_lock_reserve(buffer,
-			sys_data->enter_event->event.type, size, irq_flags, pc);
+			sys_data->enter_event->event.type, size, trace_ctx);
 	if (!event)
 		return;
 
@ kernel/trace/trace_syscalls.c:338 @ static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id)
 	memcpy(entry->args, args, sizeof(unsigned long) * sys_data->nb_args);
 
 	event_trigger_unlock_commit(trace_file, buffer, event, entry,
-				    irq_flags, pc);
+				    trace_ctx);
 }
 
 static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret)
@ kernel/trace/trace_syscalls.c:349 @ static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret)
 	struct syscall_metadata *sys_data;
 	struct ring_buffer_event *event;
 	struct trace_buffer *buffer;
-	unsigned long irq_flags;
-	int pc;
+	unsigned int trace_ctx;
 	int syscall_nr;
 
 	syscall_nr = trace_get_syscall_nr(current, regs);
@ kernel/trace/trace_syscalls.c:368 @ static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret)
 	if (!sys_data)
 		return;
 
-	local_save_flags(irq_flags);
-	pc = preempt_count();
+	trace_ctx = tracing_gen_ctx();
 
 	buffer = tr->array_buffer.buffer;
 	event = trace_buffer_lock_reserve(buffer,
 			sys_data->exit_event->event.type, sizeof(*entry),
-			irq_flags, pc);
+			trace_ctx);
 	if (!event)
 		return;
 
@ kernel/trace/trace_syscalls.c:382 @ static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret)
 	entry->ret = syscall_get_return_value(current, regs);
 
 	event_trigger_unlock_commit(trace_file, buffer, event, entry,
-				    irq_flags, pc);
+				    trace_ctx);
 }
 
 static int reg_event_syscall_enter(struct trace_event_file *file,
@ kernel/trace/trace_uprobe.c:968 @ static void __uprobe_trace_func(struct trace_uprobe *tu,
 	esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
 	size = esize + tu->tp.size + dsize;
 	event = trace_event_buffer_lock_reserve(&buffer, trace_file,
-						call->event.type, size, 0, 0);
+						call->event.type, size, 0);
 	if (!event)
 		return;
 
@ kernel/trace/trace_uprobe.c:984 @ static void __uprobe_trace_func(struct trace_uprobe *tu,
 
 	memcpy(data, ucb->buf, tu->tp.size + dsize);
 
-	event_trigger_unlock_commit(trace_file, buffer, event, entry, 0, 0);
+	event_trigger_unlock_commit(trace_file, buffer, event, entry, 0);
 }
 
 /* uprobe handler */
@ kernel/workqueue.c:4922 @ static void unbind_workers(int cpu)
 		pool->flags |= POOL_DISASSOCIATED;
 
 		raw_spin_unlock_irq(&pool->lock);
+
+		for_each_pool_worker(worker, pool)
+			WARN_ON_ONCE(set_cpus_allowed_ptr(worker->task, cpu_active_mask) < 0);
+
 		mutex_unlock(&wq_pool_attach_mutex);
 
 		/*
@ lib/Kconfig.debug:1331 @ config DEBUG_ATOMIC_SLEEP
 
 config DEBUG_LOCKING_API_SELFTESTS
 	bool "Locking API boot-time self-tests"
-	depends on DEBUG_KERNEL
+	depends on DEBUG_KERNEL && !PREEMPT_RT
 	help
 	  Say Y here if you want the kernel to run a short self-test during
 	  bootup. The self-test checks whether common types of locking bugs
@ lib/bug.c:205 @ enum bug_trap_type report_bug(unsigned long bugaddr, struct pt_regs *regs)
 	else
 		pr_crit("Kernel BUG at %pB [verbose debug info unavailable]\n",
 			(void *)bugaddr);
+	pr_flush(1000, true);
 
 	return BUG_TRAP_TYPE_BUG;
 }
@ lib/cpumask.c:264 @ int cpumask_any_and_distribute(const struct cpumask *src1p,
 	return next;
 }
 EXPORT_SYMBOL(cpumask_any_and_distribute);
+
+int cpumask_any_distribute(const struct cpumask *srcp)
+{
+	int next, prev;
+
+	/* NOTE: our first selection will skip 0. */
+	prev = __this_cpu_read(distribute_cpu_mask_prev);
+
+	next = cpumask_next(prev, srcp);
+	if (next >= nr_cpu_ids)
+		next = cpumask_first(srcp);
+
+	if (next < nr_cpu_ids)
+		__this_cpu_write(distribute_cpu_mask_prev, next);
+
+	return next;
+}
+EXPORT_SYMBOL(cpumask_any_distribute);
@ lib/debugobjects.c:560 @ __debug_object_init(void *addr, const struct debug_obj_descr *descr, int onstack
 	struct debug_obj *obj;
 	unsigned long flags;
 
-	fill_pool();
+#ifdef CONFIG_PREEMPT_RT
+	if (preempt_count() == 0 && !irqs_disabled())
+#endif
+		fill_pool();
 
 	db = get_bucket((unsigned long) addr);
 
@ lib/dump_stack.c:15 @
 #include <linux/atomic.h>
 #include <linux/kexec.h>
 #include <linux/utsname.h>
+#include <linux/stop_machine.h>
 
 static char dump_stack_arch_desc_str[128];
 
@ lib/dump_stack.c:61 @ void dump_stack_print_info(const char *log_lvl)
 		       log_lvl, dump_stack_arch_desc_str);
 
 	print_worker_info(log_lvl, current);
+	print_stop_info(log_lvl, current);
 }
 
 /**
@ lib/irq_poll.c:40 @ void irq_poll_sched(struct irq_poll *iop)
 	list_add_tail(&iop->list, this_cpu_ptr(&blk_cpu_iopoll));
 	raise_softirq_irqoff(IRQ_POLL_SOFTIRQ);
 	local_irq_restore(flags);
+	preempt_check_resched_rt();
 }
 EXPORT_SYMBOL(irq_poll_sched);
 
@ lib/irq_poll.c:76 @ void irq_poll_complete(struct irq_poll *iop)
 	local_irq_save(flags);
 	__irq_poll_complete(iop);
 	local_irq_restore(flags);
+	preempt_check_resched_rt();
 }
 EXPORT_SYMBOL(irq_poll_complete);
 
@ lib/irq_poll.c:101 @ static void __latent_entropy irq_poll_softirq(struct softirq_action *h)
 		}
 
 		local_irq_enable();
+		preempt_check_resched_rt();
 
 		/* Even though interrupts have been re-enabled, this
 		 * access is safe because interrupts can only add new
@ lib/irq_poll.c:139 @ static void __latent_entropy irq_poll_softirq(struct softirq_action *h)
 		__raise_softirq_irqoff(IRQ_POLL_SOFTIRQ);
 
 	local_irq_enable();
+	preempt_check_resched_rt();
 }
 
 /**
@ lib/irq_poll.c:203 @ static int irq_poll_cpu_dead(unsigned int cpu)
 			 this_cpu_ptr(&blk_cpu_iopoll));
 	__raise_softirq_irqoff(IRQ_POLL_SOFTIRQ);
 	local_irq_enable();
+	preempt_check_resched_rt();
 
 	return 0;
 }
@ lib/locking-selftest.c:790 @ GENERATE_TESTCASE(init_held_rtmutex);
 #include "locking-selftest-spin-hardirq.h"
 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_spin)
 
+#ifndef CONFIG_PREEMPT_RT
+
 #include "locking-selftest-rlock-hardirq.h"
 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_rlock)
 
@ lib/locking-selftest.c:807 @ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_rlock)
 #include "locking-selftest-wlock-softirq.h"
 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_wlock)
 
+#endif
+
 #undef E1
 #undef E2
 
+#ifndef CONFIG_PREEMPT_RT
 /*
  * Enabling hardirqs with a softirq-safe lock held:
  */
@ lib/locking-selftest.c:845 @ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_rlock)
 #undef E1
 #undef E2
 
+#endif
+
 /*
  * Enabling irqs with an irq-safe lock held:
  */
@ lib/locking-selftest.c:870 @ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_rlock)
 #include "locking-selftest-spin-hardirq.h"
 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_spin)
 
+#ifndef CONFIG_PREEMPT_RT
+
 #include "locking-selftest-rlock-hardirq.h"
 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_rlock)
 
@ lib/locking-selftest.c:887 @ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_rlock)
 #include "locking-selftest-wlock-softirq.h"
 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_wlock)
 
+#endif
+
 #undef E1
 #undef E2
 
@ lib/locking-selftest.c:920 @ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_wlock)
 #include "locking-selftest-spin-hardirq.h"
 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_spin)
 
+#ifndef CONFIG_PREEMPT_RT
+
 #include "locking-selftest-rlock-hardirq.h"
 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_rlock)
 
@ lib/locking-selftest.c:937 @ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_rlock)
 #include "locking-selftest-wlock-softirq.h"
 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_wlock)
 
+#endif
+
 #undef E1
 #undef E2
 #undef E3
@ lib/locking-selftest.c:972 @ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_wlock)
 #include "locking-selftest-spin-hardirq.h"
 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_spin)
 
+#ifndef CONFIG_PREEMPT_RT
+
 #include "locking-selftest-rlock-hardirq.h"
 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_rlock)
 
@ lib/locking-selftest.c:989 @ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_rlock)
 #include "locking-selftest-wlock-softirq.h"
 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_wlock)
 
+#endif
+
 #undef E1
 #undef E2
 #undef E3
 
+#ifndef CONFIG_PREEMPT_RT
+
 /*
  * read-lock / write-lock irq inversion.
  *
@ lib/locking-selftest.c:1186 @ GENERATE_PERMUTATIONS_3_EVENTS(W1W2_R2R3_R3W1)
 #undef E1
 #undef E2
 #undef E3
+
+#endif
+
+#ifndef CONFIG_PREEMPT_RT
+
 /*
  * read-lock / write-lock recursion that is actually safe.
  */
@ lib/locking-selftest.c:1237 @ GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion_soft_wlock)
 #undef E2
 #undef E3
 
+#endif
+
 /*
  * read-lock / write-lock recursion that is unsafe.
  */
@ lib/locking-selftest.c:2487 @ void locking_selftest(void)
 
 	printk("  --------------------------------------------------------------------------\n");
 
+#ifndef CONFIG_PREEMPT_RT
 	/*
 	 * irq-context testcases:
 	 */
@ lib/locking-selftest.c:2502 @ void locking_selftest(void)
 	DO_TESTCASE_6x2x2RW("irq read-recursion #2", irq_read_recursion2);
 	DO_TESTCASE_6x2x2RW("irq read-recursion #3", irq_read_recursion3);
 
+#else
+	/* On -rt, we only do hardirq context test for raw spinlock */
+	DO_TESTCASE_1B("hard-irqs-on + irq-safe-A", irqsafe1_hard_spin, 12);
+	DO_TESTCASE_1B("hard-irqs-on + irq-safe-A", irqsafe1_hard_spin, 21);
+
+	DO_TESTCASE_1B("hard-safe-A + irqs-on", irqsafe2B_hard_spin, 12);
+	DO_TESTCASE_1B("hard-safe-A + irqs-on", irqsafe2B_hard_spin, 21);
+
+	DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 123);
+	DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 132);
+	DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 213);
+	DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 231);
+	DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 312);
+	DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 321);
+
+	DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 123);
+	DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 132);
+	DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 213);
+	DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 231);
+	DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 312);
+	DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 321);
+#endif
 	ww_tests();
 
 	force_read_lock_recursive = 0;
@ lib/nmi_backtrace.c:78 @ void nmi_trigger_cpumask_backtrace(const cpumask_t *mask,
 		touch_softlockup_watchdog();
 	}
 
-	/*
-	 * Force flush any remote buffers that might be stuck in IRQ context
-	 * and therefore could not run their irq_work.
-	 */
-	printk_safe_flush();
-
 	clear_bit_unlock(0, &backtrace_flag);
 	put_cpu();
 }
@ lib/scatterlist.c:895 @ void sg_miter_stop(struct sg_mapping_iter *miter)
 			flush_kernel_dcache_page(miter->page);
 
 		if (miter->__flags & SG_MITER_ATOMIC) {
-			WARN_ON_ONCE(preemptible());
+			WARN_ON_ONCE(!pagefault_disabled());
 			kunmap_atomic(miter->addr);
 		} else
 			kunmap(miter->page);
@ lib/smp_processor_id.c:29 @ unsigned int check_preemption_disabled(const char *what1, const char *what2)
 	if (current->nr_cpus_allowed == 1)
 		goto out;
 
+#ifdef CONFIG_SMP
+	if (current->migration_disabled)
+		goto out;
+#endif
+
 	/*
 	 * It is valid to assume CPU-locality during early bootup:
 	 */
@ lib/test_lockup.c:483 @ static int __init test_lockup_init(void)
 		return -EINVAL;
 
 #ifdef CONFIG_DEBUG_SPINLOCK
+#ifdef CONFIG_PREEMPT_RT
+	if (test_magic(lock_spinlock_ptr,
+		       offsetof(spinlock_t, lock.wait_lock.magic),
+		       SPINLOCK_MAGIC) ||
+	    test_magic(lock_rwlock_ptr,
+		       offsetof(rwlock_t, rtmutex.wait_lock.magic),
+		       SPINLOCK_MAGIC) ||
+	    test_magic(lock_mutex_ptr,
+		       offsetof(struct mutex, lock.wait_lock.magic),
+		       SPINLOCK_MAGIC) ||
+	    test_magic(lock_rwsem_ptr,
+		       offsetof(struct rw_semaphore, rtmutex.wait_lock.magic),
+		       SPINLOCK_MAGIC))
+		return -EINVAL;
+#else
 	if (test_magic(lock_spinlock_ptr,
 		       offsetof(spinlock_t, rlock.magic),
 		       SPINLOCK_MAGIC) ||
@ lib/test_lockup.c:511 @ static int __init test_lockup_init(void)
 		       offsetof(struct rw_semaphore, wait_lock.magic),
 		       SPINLOCK_MAGIC))
 		return -EINVAL;
+#endif
 #endif
 
 	if ((wait_state != TASK_RUNNING ||
@ localversion-rt:1 @
+-rt60
@ mm/Kconfig:390 @ config NOMMU_INITIAL_TRIM_EXCESS
 
 config TRANSPARENT_HUGEPAGE
 	bool "Transparent Hugepage Support"
-	depends on HAVE_ARCH_TRANSPARENT_HUGEPAGE
+	depends on HAVE_ARCH_TRANSPARENT_HUGEPAGE && !PREEMPT_RT
 	select COMPACTION
 	select XARRAY_MULTI
 	help
@ mm/Kconfig:862 @ config ARCH_HAS_HUGEPD
 config MAPPING_DIRTY_HELPERS
         bool
 
+config KMAP_LOCAL
+	bool
+
 endmenu
@ mm/highmem.c:34 @
 #include <asm/tlbflush.h>
 #include <linux/vmalloc.h>
 
-#if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32)
-DEFINE_PER_CPU(int, __kmap_atomic_idx);
-#endif
-
 /*
  * Virtual_count is not a pure "count".
  *  0 means that it is not mapped, and has not been mapped
@ mm/highmem.c:107 @ static inline wait_queue_head_t *get_pkmap_wait_queue_head(unsigned int color)
 atomic_long_t _totalhigh_pages __read_mostly;
 EXPORT_SYMBOL(_totalhigh_pages);
 
-EXPORT_PER_CPU_SYMBOL(__kmap_atomic_idx);
-
-unsigned int nr_free_highpages (void)
+unsigned int __nr_free_highpages (void)
 {
 	struct zone *zone;
 	unsigned int pages = 0;
@ mm/highmem.c:144 @ pte_t * pkmap_page_table;
 		do { spin_unlock(&kmap_lock); (void)(flags); } while (0)
 #endif
 
-struct page *kmap_to_page(void *vaddr)
+struct page *__kmap_to_page(void *vaddr)
 {
 	unsigned long addr = (unsigned long)vaddr;
 
@ mm/highmem.c:155 @ struct page *kmap_to_page(void *vaddr)
 
 	return virt_to_page(addr);
 }
-EXPORT_SYMBOL(kmap_to_page);
+EXPORT_SYMBOL(__kmap_to_page);
 
 static void flush_all_zero_pkmaps(void)
 {
@ mm/highmem.c:197 @ static void flush_all_zero_pkmaps(void)
 		flush_tlb_kernel_range(PKMAP_ADDR(0), PKMAP_ADDR(LAST_PKMAP));
 }
 
-/**
- * kmap_flush_unused - flush all unused kmap mappings in order to remove stray mappings
- */
-void kmap_flush_unused(void)
+void __kmap_flush_unused(void)
 {
 	lock_kmap();
 	flush_all_zero_pkmaps();
@ mm/highmem.c:361 @ void kunmap_high(struct page *page)
 	if (need_wakeup)
 		wake_up(pkmap_map_wait);
 }
-
 EXPORT_SYMBOL(kunmap_high);
-#endif	/* CONFIG_HIGHMEM */
+#endif /* CONFIG_HIGHMEM */
+
+#ifdef CONFIG_KMAP_LOCAL
+
+#include <asm/kmap_size.h>
+
+/*
+ * With DEBUG_HIGHMEM the stack depth is doubled and every second
+ * slot is unused which acts as a guard page
+ */
+#ifdef CONFIG_DEBUG_HIGHMEM
+# define KM_INCR	2
+#else
+# define KM_INCR	1
+#endif
+
+static inline int kmap_local_idx_push(void)
+{
+	WARN_ON_ONCE(in_irq() && !irqs_disabled());
+	current->kmap_ctrl.idx += KM_INCR;
+	BUG_ON(current->kmap_ctrl.idx >= KM_MAX_IDX);
+	return current->kmap_ctrl.idx - 1;
+}
+
+static inline int kmap_local_idx(void)
+{
+	return current->kmap_ctrl.idx - 1;
+}
+
+static inline void kmap_local_idx_pop(void)
+{
+	current->kmap_ctrl.idx -= KM_INCR;
+	BUG_ON(current->kmap_ctrl.idx < 0);
+}
+
+#ifndef arch_kmap_local_post_map
+# define arch_kmap_local_post_map(vaddr, pteval)	do { } while (0)
+#endif
+
+#ifndef arch_kmap_local_pre_unmap
+# define arch_kmap_local_pre_unmap(vaddr)		do { } while (0)
+#endif
+
+#ifndef arch_kmap_local_post_unmap
+# define arch_kmap_local_post_unmap(vaddr)		do { } while (0)
+#endif
+
+#ifndef arch_kmap_local_map_idx
+#define arch_kmap_local_map_idx(idx, pfn)	kmap_local_calc_idx(idx)
+#endif
+
+#ifndef arch_kmap_local_unmap_idx
+#define arch_kmap_local_unmap_idx(idx, vaddr)	kmap_local_calc_idx(idx)
+#endif
+
+#ifndef arch_kmap_local_high_get
+static inline void *arch_kmap_local_high_get(struct page *page)
+{
+	return NULL;
+}
+#endif
+
+/* Unmap a local mapping which was obtained by kmap_high_get() */
+static inline bool kmap_high_unmap_local(unsigned long vaddr)
+{
+#ifdef ARCH_NEEDS_KMAP_HIGH_GET
+	if (vaddr >= PKMAP_ADDR(0) && vaddr < PKMAP_ADDR(LAST_PKMAP)) {
+		kunmap_high(pte_page(pkmap_page_table[PKMAP_NR(vaddr)]));
+		return true;
+	}
+#endif
+	return false;
+}
+
+static inline int kmap_local_calc_idx(int idx)
+{
+	return idx + KM_MAX_IDX * smp_processor_id();
+}
+
+static pte_t *__kmap_pte;
+
+static pte_t *kmap_get_pte(void)
+{
+	if (!__kmap_pte)
+		__kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
+	return __kmap_pte;
+}
+
+void *__kmap_local_pfn_prot(unsigned long pfn, pgprot_t prot)
+{
+	pte_t pteval, *kmap_pte = kmap_get_pte();
+	unsigned long vaddr;
+	int idx;
+
+	/*
+	 * Disable migration so resulting virtual address is stable
+	 * accross preemption.
+	 */
+	migrate_disable();
+	preempt_disable();
+	idx = arch_kmap_local_map_idx(kmap_local_idx_push(), pfn);
+	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+	BUG_ON(!pte_none(*(kmap_pte - idx)));
+	pteval = pfn_pte(pfn, prot);
+	set_pte_at(&init_mm, vaddr, kmap_pte - idx, pteval);
+	arch_kmap_local_post_map(vaddr, pteval);
+	current->kmap_ctrl.pteval[kmap_local_idx()] = pteval;
+	preempt_enable();
+
+	return (void *)vaddr;
+}
+EXPORT_SYMBOL_GPL(__kmap_local_pfn_prot);
+
+void *__kmap_local_page_prot(struct page *page, pgprot_t prot)
+{
+	void *kmap;
+
+	if (!PageHighMem(page))
+		return page_address(page);
+
+	/* Try kmap_high_get() if architecture has it enabled */
+	kmap = arch_kmap_local_high_get(page);
+	if (kmap)
+		return kmap;
+
+	return __kmap_local_pfn_prot(page_to_pfn(page), prot);
+}
+EXPORT_SYMBOL(__kmap_local_page_prot);
+
+void kunmap_local_indexed(void *vaddr)
+{
+	unsigned long addr = (unsigned long) vaddr & PAGE_MASK;
+	pte_t *kmap_pte = kmap_get_pte();
+	int idx;
+
+	if (addr < __fix_to_virt(FIX_KMAP_END) ||
+	    addr > __fix_to_virt(FIX_KMAP_BEGIN)) {
+		/*
+		 * Handle mappings which were obtained by kmap_high_get()
+		 * first as the virtual address of such mappings is below
+		 * PAGE_OFFSET. Warn for all other addresses which are in
+		 * the user space part of the virtual address space.
+		 */
+		if (!kmap_high_unmap_local(addr))
+			WARN_ON_ONCE(addr < PAGE_OFFSET);
+		return;
+	}
+
+	preempt_disable();
+	idx = arch_kmap_local_unmap_idx(kmap_local_idx(), addr);
+	WARN_ON_ONCE(addr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
+
+	arch_kmap_local_pre_unmap(addr);
+	pte_clear(&init_mm, addr, kmap_pte - idx);
+	arch_kmap_local_post_unmap(addr);
+	current->kmap_ctrl.pteval[kmap_local_idx()] = __pte(0);
+	kmap_local_idx_pop();
+	preempt_enable();
+	migrate_enable();
+}
+EXPORT_SYMBOL(kunmap_local_indexed);
+
+/*
+ * Invoked before switch_to(). This is safe even when during or after
+ * clearing the maps an interrupt which needs a kmap_local happens because
+ * the task::kmap_ctrl.idx is not modified by the unmapping code so a
+ * nested kmap_local will use the next unused index and restore the index
+ * on unmap. The already cleared kmaps of the outgoing task are irrelevant
+ * because the interrupt context does not know about them. The same applies
+ * when scheduling back in for an interrupt which happens before the
+ * restore is complete.
+ */
+void __kmap_local_sched_out(void)
+{
+	struct task_struct *tsk = current;
+	pte_t *kmap_pte = kmap_get_pte();
+	int i;
+
+	/* Clear kmaps */
+	for (i = 0; i < tsk->kmap_ctrl.idx; i++) {
+		pte_t pteval = tsk->kmap_ctrl.pteval[i];
+		unsigned long addr;
+		int idx;
+
+		/* With debug all even slots are unmapped and act as guard */
+		if (IS_ENABLED(CONFIG_DEBUG_HIGHMEM) && !(i & 0x01)) {
+			WARN_ON_ONCE(!pte_none(pteval));
+			continue;
+		}
+		if (WARN_ON_ONCE(pte_none(pteval)))
+			continue;
+
+		/*
+		 * This is a horrible hack for XTENSA to calculate the
+		 * coloured PTE index. Uses the PFN encoded into the pteval
+		 * and the map index calculation because the actual mapped
+		 * virtual address is not stored in task::kmap_ctrl.
+		 * For any sane architecture this is optimized out.
+		 */
+		idx = arch_kmap_local_map_idx(i, pte_pfn(pteval));
+
+		addr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+		arch_kmap_local_pre_unmap(addr);
+		pte_clear(&init_mm, addr, kmap_pte - idx);
+		arch_kmap_local_post_unmap(addr);
+	}
+}
+
+void __kmap_local_sched_in(void)
+{
+	struct task_struct *tsk = current;
+	pte_t *kmap_pte = kmap_get_pte();
+	int i;
+
+	/* Restore kmaps */
+	for (i = 0; i < tsk->kmap_ctrl.idx; i++) {
+		pte_t pteval = tsk->kmap_ctrl.pteval[i];
+		unsigned long addr;
+		int idx;
+
+		/* With debug all even slots are unmapped and act as guard */
+		if (IS_ENABLED(CONFIG_DEBUG_HIGHMEM) && !(i & 0x01)) {
+			WARN_ON_ONCE(!pte_none(pteval));
+			continue;
+		}
+		if (WARN_ON_ONCE(pte_none(pteval)))
+			continue;
+
+		/* See comment in __kmap_local_sched_out() */
+		idx = arch_kmap_local_map_idx(i, pte_pfn(pteval));
+		addr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+		set_pte_at(&init_mm, addr, kmap_pte - idx, pteval);
+		arch_kmap_local_post_map(addr, pteval);
+	}
+}
+
+void kmap_local_fork(struct task_struct *tsk)
+{
+	if (WARN_ON_ONCE(tsk->kmap_ctrl.idx))
+		memset(&tsk->kmap_ctrl, 0, sizeof(tsk->kmap_ctrl));
+}
+
+#endif
 
 #if defined(HASHED_PAGE_VIRTUAL)
 
@ mm/memcontrol.c:66 @
 #include <net/sock.h>
 #include <net/ip.h>
 #include "slab.h"
+#include <linux/local_lock.h>
 
 #include <linux/uaccess.h>
 
@ mm/memcontrol.c:97 @ bool cgroup_memory_noswap __read_mostly;
 static DECLARE_WAIT_QUEUE_HEAD(memcg_cgwb_frn_waitq);
 #endif
 
+struct event_lock {
+	local_lock_t l;
+};
+static DEFINE_PER_CPU(struct event_lock, event_lock) = {
+	.l      = INIT_LOCAL_LOCK(l),
+};
+
 /* Whether legacy memory+swap accounting is active */
 static bool do_memsw_account(void)
 {
@ mm/memcontrol.c:827 @ void __mod_memcg_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx,
 	pn = container_of(lruvec, struct mem_cgroup_per_node, lruvec);
 	memcg = pn->memcg;
 
+	preempt_disable_rt();
 	/* Update memcg */
 	__mod_memcg_state(memcg, idx, val);
 
@ mm/memcontrol.c:847 @ void __mod_memcg_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx,
 		x = 0;
 	}
 	__this_cpu_write(pn->lruvec_stat_cpu->count[idx], x);
+	preempt_enable_rt();
 }
 
 /**
@ mm/memcontrol.c:2213 @ void unlock_page_memcg(struct page *page)
 EXPORT_SYMBOL(unlock_page_memcg);
 
 struct memcg_stock_pcp {
+	local_lock_t lock;
 	struct mem_cgroup *cached; /* this never be root cgroup */
 	unsigned int nr_pages;
 
@ mm/memcontrol.c:2265 @ static bool consume_stock(struct mem_cgroup *memcg, unsigned int nr_pages)
 	if (nr_pages > MEMCG_CHARGE_BATCH)
 		return ret;
 
-	local_irq_save(flags);
+	local_lock_irqsave(&memcg_stock.lock, flags);
 
 	stock = this_cpu_ptr(&memcg_stock);
 	if (memcg == stock->cached && stock->nr_pages >= nr_pages) {
@ mm/memcontrol.c:2273 @ static bool consume_stock(struct mem_cgroup *memcg, unsigned int nr_pages)
 		ret = true;
 	}
 
-	local_irq_restore(flags);
+	local_unlock_irqrestore(&memcg_stock.lock, flags);
 
 	return ret;
 }
@ mm/memcontrol.c:2308 @ static void drain_local_stock(struct work_struct *dummy)
 	 * The only protection from memory hotplug vs. drain_stock races is
 	 * that we always operate on local CPU stock here with IRQ disabled
 	 */
-	local_irq_save(flags);
+	local_lock_irqsave(&memcg_stock.lock, flags);
 
 	stock = this_cpu_ptr(&memcg_stock);
 	drain_obj_stock(stock);
 	drain_stock(stock);
 	clear_bit(FLUSHING_CACHED_CHARGE, &stock->flags);
 
-	local_irq_restore(flags);
+	local_unlock_irqrestore(&memcg_stock.lock, flags);
 }
 
 /*
@ mm/memcontrol.c:2327 @ static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages)
 	struct memcg_stock_pcp *stock;
 	unsigned long flags;
 
-	local_irq_save(flags);
+	local_lock_irqsave(&memcg_stock.lock, flags);
 
 	stock = this_cpu_ptr(&memcg_stock);
 	if (stock->cached != memcg) { /* reset if necessary */
@ mm/memcontrol.c:2340 @ static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages)
 	if (stock->nr_pages > MEMCG_CHARGE_BATCH)
 		drain_stock(stock);
 
-	local_irq_restore(flags);
+	local_unlock_irqrestore(&memcg_stock.lock, flags);
 }
 
 /*
@ mm/memcontrol.c:2360 @ static void drain_all_stock(struct mem_cgroup *root_memcg)
 	 * as well as workers from this path always operate on the local
 	 * per-cpu data. CPU up doesn't touch memcg_stock at all.
 	 */
-	curcpu = get_cpu();
+	curcpu = get_cpu_light();
 	for_each_online_cpu(cpu) {
 		struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu);
 		struct mem_cgroup *memcg;
@ mm/memcontrol.c:2383 @ static void drain_all_stock(struct mem_cgroup *root_memcg)
 				schedule_work_on(cpu, &stock->work);
 		}
 	}
-	put_cpu();
+	put_cpu_light();
 	mutex_unlock(&percpu_charge_mutex);
 }
 
@ mm/memcontrol.c:3148 @ static bool consume_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes)
 	unsigned long flags;
 	bool ret = false;
 
-	local_irq_save(flags);
+	local_lock_irqsave(&memcg_stock.lock, flags);
 
 	stock = this_cpu_ptr(&memcg_stock);
 	if (objcg == stock->cached_objcg && stock->nr_bytes >= nr_bytes) {
@ mm/memcontrol.c:3156 @ static bool consume_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes)
 		ret = true;
 	}
 
-	local_irq_restore(flags);
+	local_unlock_irqrestore(&memcg_stock.lock, flags);
 
 	return ret;
 }
@ mm/memcontrol.c:3223 @ static void refill_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes)
 	struct memcg_stock_pcp *stock;
 	unsigned long flags;
 
-	local_irq_save(flags);
+	local_lock_irqsave(&memcg_stock.lock, flags);
 
 	stock = this_cpu_ptr(&memcg_stock);
 	if (stock->cached_objcg != objcg) { /* reset if necessary */
@ mm/memcontrol.c:3237 @ static void refill_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes)
 	if (stock->nr_bytes > PAGE_SIZE)
 		drain_obj_stock(stock);
 
-	local_irq_restore(flags);
+	local_unlock_irqrestore(&memcg_stock.lock, flags);
 }
 
 int obj_cgroup_charge(struct obj_cgroup *objcg, gfp_t gfp, size_t size)
@ mm/memcontrol.c:5742 @ static int mem_cgroup_move_account(struct page *page,
 
 	ret = 0;
 
-	local_irq_disable();
+	local_lock_irq(&event_lock.l);
 	mem_cgroup_charge_statistics(to, page, nr_pages);
 	memcg_check_events(to, page);
 	mem_cgroup_charge_statistics(from, page, -nr_pages);
 	memcg_check_events(from, page);
-	local_irq_enable();
+	local_unlock_irq(&event_lock.l);
 out_unlock:
 	unlock_page(page);
 out:
@ mm/memcontrol.c:6817 @ int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask)
 	css_get(&memcg->css);
 	commit_charge(page, memcg);
 
-	local_irq_disable();
+	local_lock_irq(&event_lock.l);
 	mem_cgroup_charge_statistics(memcg, page, nr_pages);
 	memcg_check_events(memcg, page);
-	local_irq_enable();
+	local_unlock_irq(&event_lock.l);
 
 	/*
 	 * Cgroup1's unified memory+swap counter has been charged with the
@ mm/memcontrol.c:6876 @ static void uncharge_batch(const struct uncharge_gather *ug)
 		memcg_oom_recover(ug->memcg);
 	}
 
-	local_irq_save(flags);
+	local_lock_irqsave(&event_lock.l, flags);
 	__count_memcg_events(ug->memcg, PGPGOUT, ug->pgpgout);
 	__this_cpu_add(ug->memcg->vmstats_percpu->nr_page_events, ug->nr_pages);
 	memcg_check_events(ug->memcg, ug->dummy_page);
-	local_irq_restore(flags);
+	local_unlock_irqrestore(&event_lock.l, flags);
 
 	/* drop reference from uncharge_page */
 	css_put(&ug->memcg->css);
@ mm/memcontrol.c:7034 @ void mem_cgroup_migrate(struct page *oldpage, struct page *newpage)
 	css_get(&memcg->css);
 	commit_charge(newpage, memcg);
 
-	local_irq_save(flags);
+	local_lock_irqsave(&event_lock.l, flags);
 	mem_cgroup_charge_statistics(memcg, newpage, nr_pages);
 	memcg_check_events(memcg, newpage);
-	local_irq_restore(flags);
+	local_unlock_irqrestore(&event_lock.l, flags);
 }
 
 DEFINE_STATIC_KEY_FALSE(memcg_sockets_enabled_key);
@ mm/memcontrol.c:7157 @ static int __init mem_cgroup_init(void)
 	cpuhp_setup_state_nocalls(CPUHP_MM_MEMCQ_DEAD, "mm/memctrl:dead", NULL,
 				  memcg_hotplug_cpu_dead);
 
-	for_each_possible_cpu(cpu)
-		INIT_WORK(&per_cpu_ptr(&memcg_stock, cpu)->work,
-			  drain_local_stock);
+	for_each_possible_cpu(cpu) {
+		struct memcg_stock_pcp *stock;
+
+		stock = per_cpu_ptr(&memcg_stock, cpu);
+		INIT_WORK(&stock->work, drain_local_stock);
+		local_lock_init(&stock->lock);
+	}
 
 	for_each_node(node) {
 		struct mem_cgroup_tree_per_node *rtpn;
@ mm/memcontrol.c:7212 @ void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
 	struct mem_cgroup *memcg, *swap_memcg;
 	unsigned int nr_entries;
 	unsigned short oldid;
+	unsigned long flags;
 
 	VM_BUG_ON_PAGE(PageLRU(page), page);
 	VM_BUG_ON_PAGE(page_count(page), page);
@ mm/memcontrol.c:7258 @ void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
 	 * important here to have the interrupts disabled because it is the
 	 * only synchronisation we have for updating the per-CPU variables.
 	 */
+	local_lock_irqsave(&event_lock.l, flags);
+#ifndef CONFIG_PREEMPT_RT
 	VM_BUG_ON(!irqs_disabled());
+#endif
 	mem_cgroup_charge_statistics(memcg, page, -nr_entries);
 	memcg_check_events(memcg, page);
+	local_unlock_irqrestore(&event_lock.l, flags);
 
 	css_put(&memcg->css);
 }
@ mm/page_alloc.c:64 @
 #include <linux/hugetlb.h>
 #include <linux/sched/rt.h>
 #include <linux/sched/mm.h>
+#include <linux/local_lock.h>
 #include <linux/page_owner.h>
 #include <linux/kthread.h>
 #include <linux/memcontrol.h>
@ mm/page_alloc.c:390 @ EXPORT_SYMBOL(nr_node_ids);
 EXPORT_SYMBOL(nr_online_nodes);
 #endif
 
+struct pa_lock {
+	local_lock_t l;
+};
+static DEFINE_PER_CPU(struct pa_lock, pa_lock) = {
+	.l	= INIT_LOCAL_LOCK(l),
+};
+
 int page_group_by_mobility_disabled __read_mostly;
 
 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
@ mm/page_alloc.c:1342 @ static inline void prefetch_buddy(struct page *page)
 }
 
 /*
- * Frees a number of pages from the PCP lists
+ * Frees a number of pages which have been collected from the pcp lists.
  * Assumes all pages on list are in same zone, and of same order.
  * count is the number of pages to free.
  *
@ mm/page_alloc.c:1352 @ static inline void prefetch_buddy(struct page *page)
  * And clear the zone's pages_scanned counter, to hold off the "all pages are
  * pinned" detection logic.
  */
-static void free_pcppages_bulk(struct zone *zone, int count,
-					struct per_cpu_pages *pcp)
+static void free_pcppages_bulk(struct zone *zone, struct list_head *head,
+			       bool zone_retry)
+{
+	bool isolated_pageblocks;
+	struct page *page, *tmp;
+	unsigned long flags;
+
+	spin_lock_irqsave(&zone->lock, flags);
+	isolated_pageblocks = has_isolate_pageblock(zone);
+
+	/*
+	 * Use safe version since after __free_one_page(),
+	 * page->lru.next will not point to original list.
+	 */
+	list_for_each_entry_safe(page, tmp, head, lru) {
+		int mt = get_pcppage_migratetype(page);
+
+		if (page_zone(page) != zone) {
+			/*
+			 * free_unref_page_list() sorts pages by zone. If we end
+			 * up with pages from a different NUMA nodes belonging
+			 * to the same ZONE index then we need to redo with the
+			 * correct ZONE pointer. Skip the page for now, redo it
+			 * on the next iteration.
+			 */
+			WARN_ON_ONCE(zone_retry == false);
+			if (zone_retry)
+				continue;
+		}
+
+		/* MIGRATE_ISOLATE page should not go to pcplists */
+		VM_BUG_ON_PAGE(is_migrate_isolate(mt), page);
+		/* Pageblock could have been isolated meanwhile */
+		if (unlikely(isolated_pageblocks))
+			mt = get_pageblock_migratetype(page);
+
+		list_del(&page->lru);
+		__free_one_page(page, page_to_pfn(page), zone, 0, mt, FPI_NONE);
+		trace_mm_page_pcpu_drain(page, 0, mt);
+	}
+	spin_unlock_irqrestore(&zone->lock, flags);
+}
+
+static void isolate_pcp_pages(int count, struct per_cpu_pages *pcp,
+			      struct list_head *dst)
 {
 	int migratetype = 0;
 	int batch_free = 0;
 	int prefetch_nr = 0;
-	bool isolated_pageblocks;
-	struct page *page, *tmp;
-	LIST_HEAD(head);
+	struct page *page;
 
 	/*
 	 * Ensure proper count is passed which otherwise would stuck in the
@ mm/page_alloc.c:1438 @ static void free_pcppages_bulk(struct zone *zone, int count,
 			if (bulkfree_pcp_prepare(page))
 				continue;
 
-			list_add_tail(&page->lru, &head);
+			list_add_tail(&page->lru, dst);
 
 			/*
 			 * We are going to put the page back to the global
@ mm/page_alloc.c:1453 @ static void free_pcppages_bulk(struct zone *zone, int count,
 				prefetch_buddy(page);
 		} while (--count && --batch_free && !list_empty(list));
 	}
-
-	spin_lock(&zone->lock);
-	isolated_pageblocks = has_isolate_pageblock(zone);
-
-	/*
-	 * Use safe version since after __free_one_page(),
-	 * page->lru.next will not point to original list.
-	 */
-	list_for_each_entry_safe(page, tmp, &head, lru) {
-		int mt = get_pcppage_migratetype(page);
-		/* MIGRATE_ISOLATE page should not go to pcplists */
-		VM_BUG_ON_PAGE(is_migrate_isolate(mt), page);
-		/* Pageblock could have been isolated meanwhile */
-		if (unlikely(isolated_pageblocks))
-			mt = get_pageblock_migratetype(page);
-
-		__free_one_page(page, page_to_pfn(page), zone, 0, mt, FPI_NONE);
-		trace_mm_page_pcpu_drain(page, 0, mt);
-	}
-	spin_unlock(&zone->lock);
 }
 
 static void free_one_page(struct zone *zone,
@ mm/page_alloc.c:1554 @ static void __free_pages_ok(struct page *page, unsigned int order,
 		return;
 
 	migratetype = get_pfnblock_migratetype(page, pfn);
-	local_irq_save(flags);
+	local_lock_irqsave(&pa_lock.l, flags);
 	__count_vm_events(PGFREE, 1 << order);
 	free_one_page(page_zone(page), page, pfn, order, migratetype,
 		      fpi_flags);
-	local_irq_restore(flags);
+	local_unlock_irqrestore(&pa_lock.l, flags);
 }
 
 void __free_pages_core(struct page *page, unsigned int order)
@ mm/page_alloc.c:2970 @ void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp)
 {
 	unsigned long flags;
 	int to_drain, batch;
+	LIST_HEAD(dst);
 
-	local_irq_save(flags);
+	local_lock_irqsave(&pa_lock.l, flags);
 	batch = READ_ONCE(pcp->batch);
 	to_drain = min(pcp->count, batch);
 	if (to_drain > 0)
-		free_pcppages_bulk(zone, to_drain, pcp);
-	local_irq_restore(flags);
+		isolate_pcp_pages(to_drain, pcp, &dst);
+
+	local_unlock_irqrestore(&pa_lock.l, flags);
+
+	if (to_drain > 0)
+		free_pcppages_bulk(zone, &dst, false);
 }
 #endif
 
@ mm/page_alloc.c:2997 @ static void drain_pages_zone(unsigned int cpu, struct zone *zone)
 	unsigned long flags;
 	struct per_cpu_pageset *pset;
 	struct per_cpu_pages *pcp;
+	LIST_HEAD(dst);
+	int count;
 
-	local_irq_save(flags);
+	local_lock_irqsave(&pa_lock.l, flags);
 	pset = per_cpu_ptr(zone->pageset, cpu);
 
 	pcp = &pset->pcp;
-	if (pcp->count)
-		free_pcppages_bulk(zone, pcp->count, pcp);
-	local_irq_restore(flags);
+	count = pcp->count;
+	if (count)
+		isolate_pcp_pages(count, pcp, &dst);
+
+	local_unlock_irqrestore(&pa_lock.l, flags);
+
+	if (count)
+		free_pcppages_bulk(zone, &dst, false);
 }
 
 /*
@ mm/page_alloc.c:3059 @ static void drain_local_pages_wq(struct work_struct *work)
 	 * cpu which is allright but we also have to make sure to not move to
 	 * a different one.
 	 */
-	preempt_disable();
+	migrate_disable();
 	drain_local_pages(drain->zone);
-	preempt_enable();
+	migrate_enable();
 }
 
 /*
@ mm/page_alloc.c:3210 @ static bool free_unref_page_prepare(struct page *page, unsigned long pfn)
 	return true;
 }
 
-static void free_unref_page_commit(struct page *page, unsigned long pfn)
+static void free_unref_page_commit(struct page *page, unsigned long pfn,
+				   struct list_head *dst)
 {
 	struct zone *zone = page_zone(page);
 	struct per_cpu_pages *pcp;
@ mm/page_alloc.c:3241 @ static void free_unref_page_commit(struct page *page, unsigned long pfn)
 	pcp->count++;
 	if (pcp->count >= pcp->high) {
 		unsigned long batch = READ_ONCE(pcp->batch);
-		free_pcppages_bulk(zone, batch, pcp);
+
+		isolate_pcp_pages(batch, pcp, dst);
 	}
 }
 
@ mm/page_alloc.c:3253 @ void free_unref_page(struct page *page)
 {
 	unsigned long flags;
 	unsigned long pfn = page_to_pfn(page);
+	struct zone *zone = page_zone(page);
+	LIST_HEAD(dst);
 
 	if (!free_unref_page_prepare(page, pfn))
 		return;
 
-	local_irq_save(flags);
-	free_unref_page_commit(page, pfn);
-	local_irq_restore(flags);
+	local_lock_irqsave(&pa_lock.l, flags);
+	free_unref_page_commit(page, pfn, &dst);
+	local_unlock_irqrestore(&pa_lock.l, flags);
+	if (!list_empty(&dst))
+		free_pcppages_bulk(zone, &dst, false);
 }
 
 /*
@ mm/page_alloc.c:3274 @ void free_unref_page_list(struct list_head *list)
 	struct page *page, *next;
 	unsigned long flags, pfn;
 	int batch_count = 0;
+	struct list_head dsts[__MAX_NR_ZONES];
+	int i;
+
+	for (i = 0; i < __MAX_NR_ZONES; i++)
+		INIT_LIST_HEAD(&dsts[i]);
 
 	/* Prepare pages for freeing */
 	list_for_each_entry_safe(page, next, list, lru) {
@ mm/page_alloc.c:3288 @ void free_unref_page_list(struct list_head *list)
 		set_page_private(page, pfn);
 	}
 
-	local_irq_save(flags);
+	local_lock_irqsave(&pa_lock.l, flags);
 	list_for_each_entry_safe(page, next, list, lru) {
 		unsigned long pfn = page_private(page);
+		enum zone_type type;
 
 		set_page_private(page, 0);
 		trace_mm_page_free_batched(page);
-		free_unref_page_commit(page, pfn);
+		type = page_zonenum(page);
+		free_unref_page_commit(page, pfn, &dsts[type]);
 
 		/*
 		 * Guard against excessive IRQ disabled times when we get
 		 * a large list of pages to free.
 		 */
 		if (++batch_count == SWAP_CLUSTER_MAX) {
-			local_irq_restore(flags);
+			local_unlock_irqrestore(&pa_lock.l, flags);
 			batch_count = 0;
-			local_irq_save(flags);
+			local_lock_irqsave(&pa_lock.l, flags);
 		}
 	}
-	local_irq_restore(flags);
+	local_unlock_irqrestore(&pa_lock.l, flags);
+
+	for (i = 0; i < __MAX_NR_ZONES; ) {
+		struct page *page;
+		struct zone *zone;
+
+		if (list_empty(&dsts[i])) {
+			i++;
+			continue;
+		}
+
+		page = list_first_entry(&dsts[i], struct page, lru);
+		zone = page_zone(page);
+
+		free_pcppages_bulk(zone, &dsts[i], true);
+	}
 }
 
 /*
@ mm/page_alloc.c:3479 @ static struct page *rmqueue_pcplist(struct zone *preferred_zone,
 	struct page *page;
 	unsigned long flags;
 
-	local_irq_save(flags);
+	local_lock_irqsave(&pa_lock.l, flags);
 	pcp = &this_cpu_ptr(zone->pageset)->pcp;
 	list = &pcp->lists[migratetype];
 	page = __rmqueue_pcplist(zone,  migratetype, alloc_flags, pcp, list);
@ mm/page_alloc.c:3487 @ static struct page *rmqueue_pcplist(struct zone *preferred_zone,
 		__count_zid_vm_events(PGALLOC, page_zonenum(page), 1);
 		zone_statistics(preferred_zone, zone);
 	}
-	local_irq_restore(flags);
+	local_unlock_irqrestore(&pa_lock.l, flags);
 	return page;
 }
 
@ mm/page_alloc.c:3521 @ struct page *rmqueue(struct zone *preferred_zone,
 	 * allocate greater than order-1 page units with __GFP_NOFAIL.
 	 */
 	WARN_ON_ONCE((gfp_flags & __GFP_NOFAIL) && (order > 1));
-	spin_lock_irqsave(&zone->lock, flags);
+	local_lock_irqsave(&pa_lock.l, flags);
+	spin_lock(&zone->lock);
 
 	do {
 		page = NULL;
@ mm/page_alloc.c:3548 @ struct page *rmqueue(struct zone *preferred_zone,
 
 	__count_zid_vm_events(PGALLOC, page_zonenum(page), 1 << order);
 	zone_statistics(preferred_zone, zone);
-	local_irq_restore(flags);
+	local_unlock_irqrestore(&pa_lock.l, flags);
 
 out:
 	/* Separate test+clear to avoid unnecessary atomics */
@ mm/page_alloc.c:3561 @ struct page *rmqueue(struct zone *preferred_zone,
 	return page;
 
 failed:
-	local_irq_restore(flags);
+	local_unlock_irqrestore(&pa_lock.l, flags);
 	return NULL;
 }
 
@ mm/page_alloc.c:8827 @ void zone_pcp_reset(struct zone *zone)
 	struct per_cpu_pageset *pset;
 
 	/* avoid races with drain_pages()  */
-	local_irq_save(flags);
+	local_lock_irqsave(&pa_lock.l, flags);
 	if (zone->pageset != &boot_pageset) {
 		for_each_online_cpu(cpu) {
 			pset = per_cpu_ptr(zone->pageset, cpu);
@ mm/page_alloc.c:8836 @ void zone_pcp_reset(struct zone *zone)
 		free_percpu(zone->pageset);
 		zone->pageset = &boot_pageset;
 	}
-	local_irq_restore(flags);
+	local_unlock_irqrestore(&pa_lock.l, flags);
 }
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
@ mm/shmem.c:281 @ static int shmem_reserve_inode(struct super_block *sb, ino_t *inop)
 	ino_t ino;
 
 	if (!(sb->s_flags & SB_KERNMOUNT)) {
-		spin_lock(&sbinfo->stat_lock);
+		raw_spin_lock(&sbinfo->stat_lock);
 		if (sbinfo->max_inodes) {
 			if (!sbinfo->free_inodes) {
-				spin_unlock(&sbinfo->stat_lock);
+				raw_spin_unlock(&sbinfo->stat_lock);
 				return -ENOSPC;
 			}
 			sbinfo->free_inodes--;
@ mm/shmem.c:307 @ static int shmem_reserve_inode(struct super_block *sb, ino_t *inop)
 			}
 			*inop = ino;
 		}
-		spin_unlock(&sbinfo->stat_lock);
+		raw_spin_unlock(&sbinfo->stat_lock);
 	} else if (inop) {
 		/*
 		 * __shmem_file_setup, one of our callers, is lock-free: it
@ mm/shmem.c:322 @ static int shmem_reserve_inode(struct super_block *sb, ino_t *inop)
 		 * to worry about things like glibc compatibility.
 		 */
 		ino_t *next_ino;
+
 		next_ino = per_cpu_ptr(sbinfo->ino_batch, get_cpu());
 		ino = *next_ino;
 		if (unlikely(ino % SHMEM_INO_BATCH == 0)) {
-			spin_lock(&sbinfo->stat_lock);
+			raw_spin_lock(&sbinfo->stat_lock);
 			ino = sbinfo->next_ino;
 			sbinfo->next_ino += SHMEM_INO_BATCH;
-			spin_unlock(&sbinfo->stat_lock);
+			raw_spin_unlock(&sbinfo->stat_lock);
 			if (unlikely(is_zero_ino(ino)))
 				ino++;
 		}
@ mm/shmem.c:345 @ static void shmem_free_inode(struct super_block *sb)
 {
 	struct shmem_sb_info *sbinfo = SHMEM_SB(sb);
 	if (sbinfo->max_inodes) {
-		spin_lock(&sbinfo->stat_lock);
+		raw_spin_lock(&sbinfo->stat_lock);
 		sbinfo->free_inodes++;
-		spin_unlock(&sbinfo->stat_lock);
+		raw_spin_unlock(&sbinfo->stat_lock);
 	}
 }
 
@ mm/shmem.c:1483 @ static struct mempolicy *shmem_get_sbmpol(struct shmem_sb_info *sbinfo)
 {
 	struct mempolicy *mpol = NULL;
 	if (sbinfo->mpol) {
-		spin_lock(&sbinfo->stat_lock);	/* prevent replace/use races */
+		raw_spin_lock(&sbinfo->stat_lock);	/* prevent replace/use races */
 		mpol = sbinfo->mpol;
 		mpol_get(mpol);
-		spin_unlock(&sbinfo->stat_lock);
+		raw_spin_unlock(&sbinfo->stat_lock);
 	}
 	return mpol;
 }
@ mm/shmem.c:3592 @ static int shmem_reconfigure(struct fs_context *fc)
 	struct shmem_options *ctx = fc->fs_private;
 	struct shmem_sb_info *sbinfo = SHMEM_SB(fc->root->d_sb);
 	unsigned long inodes;
+	struct mempolicy *mpol = NULL;
 	const char *err;
 
-	spin_lock(&sbinfo->stat_lock);
+	raw_spin_lock(&sbinfo->stat_lock);
 	inodes = sbinfo->max_inodes - sbinfo->free_inodes;
 	if ((ctx->seen & SHMEM_SEEN_BLOCKS) && ctx->blocks) {
 		if (!sbinfo->max_blocks) {
@ mm/shmem.c:3640 @ static int shmem_reconfigure(struct fs_context *fc)
 	 * Preserve previous mempolicy unless mpol remount option was specified.
 	 */
 	if (ctx->mpol) {
-		mpol_put(sbinfo->mpol);
+		mpol = sbinfo->mpol;
 		sbinfo->mpol = ctx->mpol;	/* transfers initial ref */
 		ctx->mpol = NULL;
 	}
-	spin_unlock(&sbinfo->stat_lock);
+	raw_spin_unlock(&sbinfo->stat_lock);
+	mpol_put(mpol);
 	return 0;
 out:
-	spin_unlock(&sbinfo->stat_lock);
+	raw_spin_unlock(&sbinfo->stat_lock);
 	return invalfc(fc, "%s", err);
 }
 
@ mm/shmem.c:3765 @ static int shmem_fill_super(struct super_block *sb, struct fs_context *fc)
 	sbinfo->mpol = ctx->mpol;
 	ctx->mpol = NULL;
 
-	spin_lock_init(&sbinfo->stat_lock);
+	raw_spin_lock_init(&sbinfo->stat_lock);
 	if (percpu_counter_init(&sbinfo->used_blocks, 0, GFP_KERNEL))
 		goto failed;
 	spin_lock_init(&sbinfo->shrinklist_lock);
@ mm/slab.c:236 @ static void kmem_cache_node_init(struct kmem_cache_node *parent)
 	parent->shared = NULL;
 	parent->alien = NULL;
 	parent->colour_next = 0;
-	spin_lock_init(&parent->list_lock);
+	raw_spin_lock_init(&parent->list_lock);
 	parent->free_objects = 0;
 	parent->free_touched = 0;
 }
@ mm/slab.c:561 @ static noinline void cache_free_pfmemalloc(struct kmem_cache *cachep,
 	page_node = page_to_nid(page);
 	n = get_node(cachep, page_node);
 
-	spin_lock(&n->list_lock);
+	raw_spin_lock(&n->list_lock);
 	free_block(cachep, &objp, 1, page_node, &list);
-	spin_unlock(&n->list_lock);
+	raw_spin_unlock(&n->list_lock);
 
 	slabs_destroy(cachep, &list);
 }
@ mm/slab.c:701 @ static void __drain_alien_cache(struct kmem_cache *cachep,
 	struct kmem_cache_node *n = get_node(cachep, node);
 
 	if (ac->avail) {
-		spin_lock(&n->list_lock);
+		raw_spin_lock(&n->list_lock);
 		/*
 		 * Stuff objects into the remote nodes shared array first.
 		 * That way we could avoid the overhead of putting the objects
@ mm/slab.c:712 @ static void __drain_alien_cache(struct kmem_cache *cachep,
 
 		free_block(cachep, ac->entry, ac->avail, node, list);
 		ac->avail = 0;
-		spin_unlock(&n->list_lock);
+		raw_spin_unlock(&n->list_lock);
 	}
 }
 
@ mm/slab.c:785 @ static int __cache_free_alien(struct kmem_cache *cachep, void *objp,
 		slabs_destroy(cachep, &list);
 	} else {
 		n = get_node(cachep, page_node);
-		spin_lock(&n->list_lock);
+		raw_spin_lock(&n->list_lock);
 		free_block(cachep, &objp, 1, page_node, &list);
-		spin_unlock(&n->list_lock);
+		raw_spin_unlock(&n->list_lock);
 		slabs_destroy(cachep, &list);
 	}
 	return 1;
@ mm/slab.c:828 @ static int init_cache_node(struct kmem_cache *cachep, int node, gfp_t gfp)
 	 */
 	n = get_node(cachep, node);
 	if (n) {
-		spin_lock_irq(&n->list_lock);
+		raw_spin_lock_irq(&n->list_lock);
 		n->free_limit = (1 + nr_cpus_node(node)) * cachep->batchcount +
 				cachep->num;
-		spin_unlock_irq(&n->list_lock);
+		raw_spin_unlock_irq(&n->list_lock);
 
 		return 0;
 	}
@ mm/slab.c:910 @ static int setup_kmem_cache_node(struct kmem_cache *cachep,
 		goto fail;
 
 	n = get_node(cachep, node);
-	spin_lock_irq(&n->list_lock);
+	raw_spin_lock_irq(&n->list_lock);
 	if (n->shared && force_change) {
 		free_block(cachep, n->shared->entry,
 				n->shared->avail, node, &list);
@ mm/slab.c:928 @ static int setup_kmem_cache_node(struct kmem_cache *cachep,
 		new_alien = NULL;
 	}
 
-	spin_unlock_irq(&n->list_lock);
+	raw_spin_unlock_irq(&n->list_lock);
 	slabs_destroy(cachep, &list);
 
 	/*
@ mm/slab.c:967 @ static void cpuup_canceled(long cpu)
 		if (!n)
 			continue;
 
-		spin_lock_irq(&n->list_lock);
+		raw_spin_lock_irq(&n->list_lock);
 
 		/* Free limit for this kmem_cache_node */
 		n->free_limit -= cachep->batchcount;
@ mm/slab.c:978 @ static void cpuup_canceled(long cpu)
 		nc->avail = 0;
 
 		if (!cpumask_empty(mask)) {
-			spin_unlock_irq(&n->list_lock);
+			raw_spin_unlock_irq(&n->list_lock);
 			goto free_slab;
 		}
 
@ mm/slab.c:992 @ static void cpuup_canceled(long cpu)
 		alien = n->alien;
 		n->alien = NULL;
 
-		spin_unlock_irq(&n->list_lock);
+		raw_spin_unlock_irq(&n->list_lock);
 
 		kfree(shared);
 		if (alien) {
@ mm/slab.c:1176 @ static void __init init_list(struct kmem_cache *cachep, struct kmem_cache_node *
 	/*
 	 * Do not assume that spinlocks can be initialized via memcpy:
 	 */
-	spin_lock_init(&ptr->list_lock);
+	raw_spin_lock_init(&ptr->list_lock);
 
 	MAKE_ALL_LISTS(cachep, ptr, nodeid);
 	cachep->node[nodeid] = ptr;
@ mm/slab.c:1347 @ slab_out_of_memory(struct kmem_cache *cachep, gfp_t gfpflags, int nodeid)
 	for_each_kmem_cache_node(cachep, node, n) {
 		unsigned long total_slabs, free_slabs, free_objs;
 
-		spin_lock_irqsave(&n->list_lock, flags);
+		raw_spin_lock_irqsave(&n->list_lock, flags);
 		total_slabs = n->total_slabs;
 		free_slabs = n->free_slabs;
 		free_objs = n->free_objects;
-		spin_unlock_irqrestore(&n->list_lock, flags);
+		raw_spin_unlock_irqrestore(&n->list_lock, flags);
 
 		pr_warn("  node %d: slabs: %ld/%ld, objs: %ld/%ld\n",
 			node, total_slabs - free_slabs, total_slabs,
@ mm/slab.c:2108 @ static void check_spinlock_acquired(struct kmem_cache *cachep)
 {
 #ifdef CONFIG_SMP
 	check_irq_off();
-	assert_spin_locked(&get_node(cachep, numa_mem_id())->list_lock);
+	assert_raw_spin_locked(&get_node(cachep, numa_mem_id())->list_lock);
 #endif
 }
 
@ mm/slab.c:2116 @ static void check_spinlock_acquired_node(struct kmem_cache *cachep, int node)
 {
 #ifdef CONFIG_SMP
 	check_irq_off();
-	assert_spin_locked(&get_node(cachep, node)->list_lock);
+	assert_raw_spin_locked(&get_node(cachep, node)->list_lock);
 #endif
 }
 
@ mm/slab.c:2156 @ static void do_drain(void *arg)
 	check_irq_off();
 	ac = cpu_cache_get(cachep);
 	n = get_node(cachep, node);
-	spin_lock(&n->list_lock);
+	raw_spin_lock(&n->list_lock);
 	free_block(cachep, ac->entry, ac->avail, node, &list);
-	spin_unlock(&n->list_lock);
+	raw_spin_unlock(&n->list_lock);
 	ac->avail = 0;
 	slabs_destroy(cachep, &list);
 }
@ mm/slab.c:2176 @ static void drain_cpu_caches(struct kmem_cache *cachep)
 			drain_alien_cache(cachep, n->alien);
 
 	for_each_kmem_cache_node(cachep, node, n) {
-		spin_lock_irq(&n->list_lock);
+		raw_spin_lock_irq(&n->list_lock);
 		drain_array_locked(cachep, n->shared, node, true, &list);
-		spin_unlock_irq(&n->list_lock);
+		raw_spin_unlock_irq(&n->list_lock);
 
 		slabs_destroy(cachep, &list);
 	}
@ mm/slab.c:2200 @ static int drain_freelist(struct kmem_cache *cache,
 	nr_freed = 0;
 	while (nr_freed < tofree && !list_empty(&n->slabs_free)) {
 
-		spin_lock_irq(&n->list_lock);
+		raw_spin_lock_irq(&n->list_lock);
 		p = n->slabs_free.prev;
 		if (p == &n->slabs_free) {
-			spin_unlock_irq(&n->list_lock);
+			raw_spin_unlock_irq(&n->list_lock);
 			goto out;
 		}
 
@ mm/slab.c:2216 @ static int drain_freelist(struct kmem_cache *cache,
 		 * to the cache.
 		 */
 		n->free_objects -= cache->num;
-		spin_unlock_irq(&n->list_lock);
+		raw_spin_unlock_irq(&n->list_lock);
 		slab_destroy(cache, page);
 		nr_freed++;
 	}
@ mm/slab.c:2652 @ static void cache_grow_end(struct kmem_cache *cachep, struct page *page)
 	INIT_LIST_HEAD(&page->slab_list);
 	n = get_node(cachep, page_to_nid(page));
 
-	spin_lock(&n->list_lock);
+	raw_spin_lock(&n->list_lock);
 	n->total_slabs++;
 	if (!page->active) {
 		list_add_tail(&page->slab_list, &n->slabs_free);
@ mm/slab.c:2662 @ static void cache_grow_end(struct kmem_cache *cachep, struct page *page)
 
 	STATS_INC_GROWN(cachep);
 	n->free_objects += cachep->num - page->active;
-	spin_unlock(&n->list_lock);
+	raw_spin_unlock(&n->list_lock);
 
 	fixup_objfreelist_debug(cachep, &list);
 }
@ mm/slab.c:2828 @ static struct page *get_first_slab(struct kmem_cache_node *n, bool pfmemalloc)
 {
 	struct page *page;
 
-	assert_spin_locked(&n->list_lock);
+	assert_raw_spin_locked(&n->list_lock);
 	page = list_first_entry_or_null(&n->slabs_partial, struct page,
 					slab_list);
 	if (!page) {
@ mm/slab.c:2855 @ static noinline void *cache_alloc_pfmemalloc(struct kmem_cache *cachep,
 	if (!gfp_pfmemalloc_allowed(flags))
 		return NULL;
 
-	spin_lock(&n->list_lock);
+	raw_spin_lock(&n->list_lock);
 	page = get_first_slab(n, true);
 	if (!page) {
-		spin_unlock(&n->list_lock);
+		raw_spin_unlock(&n->list_lock);
 		return NULL;
 	}
 
@ mm/slab.c:2867 @ static noinline void *cache_alloc_pfmemalloc(struct kmem_cache *cachep,
 
 	fixup_slab_list(cachep, n, page, &list);
 
-	spin_unlock(&n->list_lock);
+	raw_spin_unlock(&n->list_lock);
 	fixup_objfreelist_debug(cachep, &list);
 
 	return obj;
@ mm/slab.c:2926 @ static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags)
 	if (!n->free_objects && (!shared || !shared->avail))
 		goto direct_grow;
 
-	spin_lock(&n->list_lock);
+	raw_spin_lock(&n->list_lock);
 	shared = READ_ONCE(n->shared);
 
 	/* See if we can refill from the shared array */
@ mm/slab.c:2950 @ static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags)
 must_grow:
 	n->free_objects -= ac->avail;
 alloc_done:
-	spin_unlock(&n->list_lock);
+	raw_spin_unlock(&n->list_lock);
 	fixup_objfreelist_debug(cachep, &list);
 
 direct_grow:
@ mm/slab.c:3175 @ static void *____cache_alloc_node(struct kmem_cache *cachep, gfp_t flags,
 	BUG_ON(!n);
 
 	check_irq_off();
-	spin_lock(&n->list_lock);
+	raw_spin_lock(&n->list_lock);
 	page = get_first_slab(n, false);
 	if (!page)
 		goto must_grow;
@ mm/slab.c:3193 @ static void *____cache_alloc_node(struct kmem_cache *cachep, gfp_t flags,
 
 	fixup_slab_list(cachep, n, page, &list);
 
-	spin_unlock(&n->list_lock);
+	raw_spin_unlock(&n->list_lock);
 	fixup_objfreelist_debug(cachep, &list);
 	return obj;
 
 must_grow:
-	spin_unlock(&n->list_lock);
+	raw_spin_unlock(&n->list_lock);
 	page = cache_grow_begin(cachep, gfp_exact_node(flags), nodeid);
 	if (page) {
 		/* This slab isn't counted yet so don't update free_objects */
@ mm/slab.c:3376 @ static void cache_flusharray(struct kmem_cache *cachep, struct array_cache *ac)
 
 	check_irq_off();
 	n = get_node(cachep, node);
-	spin_lock(&n->list_lock);
+	raw_spin_lock(&n->list_lock);
 	if (n->shared) {
 		struct array_cache *shared_array = n->shared;
 		int max = shared_array->limit - shared_array->avail;
@ mm/slab.c:3405 @ static void cache_flusharray(struct kmem_cache *cachep, struct array_cache *ac)
 		STATS_SET_FREEABLE(cachep, i);
 	}
 #endif
-	spin_unlock(&n->list_lock);
+	raw_spin_unlock(&n->list_lock);
 	ac->avail -= batchcount;
 	memmove(ac->entry, &(ac->entry[batchcount]), sizeof(void *)*ac->avail);
 	slabs_destroy(cachep, &list);
@ mm/slab.c:3834 @ static int do_tune_cpucache(struct kmem_cache *cachep, int limit,
 
 		node = cpu_to_mem(cpu);
 		n = get_node(cachep, node);
-		spin_lock_irq(&n->list_lock);
+		raw_spin_lock_irq(&n->list_lock);
 		free_block(cachep, ac->entry, ac->avail, node, &list);
-		spin_unlock_irq(&n->list_lock);
+		raw_spin_unlock_irq(&n->list_lock);
 		slabs_destroy(cachep, &list);
 	}
 	free_percpu(prev);
@ mm/slab.c:3931 @ static void drain_array(struct kmem_cache *cachep, struct kmem_cache_node *n,
 		return;
 	}
 
-	spin_lock_irq(&n->list_lock);
+	raw_spin_lock_irq(&n->list_lock);
 	drain_array_locked(cachep, ac, node, false, &list);
-	spin_unlock_irq(&n->list_lock);
+	raw_spin_unlock_irq(&n->list_lock);
 
 	slabs_destroy(cachep, &list);
 }
@ mm/slab.c:4017 @ void get_slabinfo(struct kmem_cache *cachep, struct slabinfo *sinfo)
 
 	for_each_kmem_cache_node(cachep, node, n) {
 		check_irq_on();
-		spin_lock_irq(&n->list_lock);
+		raw_spin_lock_irq(&n->list_lock);
 
 		total_slabs += n->total_slabs;
 		free_slabs += n->free_slabs;
@ mm/slab.c:4026 @ void get_slabinfo(struct kmem_cache *cachep, struct slabinfo *sinfo)
 		if (n->shared)
 			shared_avail += n->shared->avail;
 
-		spin_unlock_irq(&n->list_lock);
+		raw_spin_unlock_irq(&n->list_lock);
 	}
 	num_objs = total_slabs * cachep->num;
 	active_slabs = total_slabs - free_slabs;
@ mm/slab.h:546 @ static inline void slab_post_alloc_hook(struct kmem_cache *s,
  * The slab lists for all objects.
  */
 struct kmem_cache_node {
-	spinlock_t list_lock;
+	raw_spinlock_t list_lock;
 
 #ifdef CONFIG_SLAB
 	struct list_head slabs_partial;	/* partial list first, better asm code */
@ mm/slub.c:438 @ static inline bool cmpxchg_double_slab(struct kmem_cache *s, struct page *page,
 
 #ifdef CONFIG_SLUB_DEBUG
 static unsigned long object_map[BITS_TO_LONGS(MAX_OBJS_PER_PAGE)];
-static DEFINE_SPINLOCK(object_map_lock);
+static DEFINE_RAW_SPINLOCK(object_map_lock);
 
 /*
  * Determine a map of object in use on a page.
@ mm/slub.c:454 @ static unsigned long *get_map(struct kmem_cache *s, struct page *page)
 
 	VM_BUG_ON(!irqs_disabled());
 
-	spin_lock(&object_map_lock);
+	raw_spin_lock(&object_map_lock);
 
 	bitmap_zero(object_map, page->objects);
 
@ mm/slub.c:467 @ static unsigned long *get_map(struct kmem_cache *s, struct page *page)
 static void put_map(unsigned long *map) __releases(&object_map_lock)
 {
 	VM_BUG_ON(map != object_map);
-	spin_unlock(&object_map_lock);
+	raw_spin_unlock(&object_map_lock);
 }
 
 static inline unsigned int size_from_object(struct kmem_cache *s)
@ mm/slub.c:1217 @ static noinline int free_debug_processing(
 	unsigned long flags;
 	int ret = 0;
 
-	spin_lock_irqsave(&n->list_lock, flags);
+	raw_spin_lock_irqsave(&n->list_lock, flags);
 	slab_lock(page);
 
 	if (s->flags & SLAB_CONSISTENCY_CHECKS) {
@ mm/slub.c:1252 @ static noinline int free_debug_processing(
 			 bulk_cnt, cnt);
 
 	slab_unlock(page);
-	spin_unlock_irqrestore(&n->list_lock, flags);
+	raw_spin_unlock_irqrestore(&n->list_lock, flags);
 	if (!ret)
 		slab_fix(s, "Object at 0x%p not freed", object);
 	return ret;
@ mm/slub.c:1497 @ static bool freelist_corrupted(struct kmem_cache *s, struct page *page,
 }
 #endif /* CONFIG_SLUB_DEBUG */
 
+struct slub_free_list {
+	raw_spinlock_t		lock;
+	struct list_head	list;
+};
+static DEFINE_PER_CPU(struct slub_free_list, slub_free_list);
+
 /*
  * Hooks for other subsystems that check memory allocations. In a typical
  * production configuration these hooks all should produce no code at all.
@ mm/slub.c:1753 @ static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node)
 	void *start, *p, *next;
 	int idx;
 	bool shuffle;
+	bool enableirqs = false;
 
 	flags &= gfp_allowed_mask;
 
 	if (gfpflags_allow_blocking(flags))
+		enableirqs = true;
+
+#ifdef CONFIG_PREEMPT_RT
+	if (system_state > SYSTEM_BOOTING && system_state < SYSTEM_SUSPEND)
+		enableirqs = true;
+#endif
+	if (enableirqs)
 		local_irq_enable();
 
 	flags |= s->allocflags;
@ mm/slub.c:1823 @ static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node)
 	page->frozen = 1;
 
 out:
-	if (gfpflags_allow_blocking(flags))
+	if (enableirqs)
 		local_irq_disable();
 	if (!page)
 		return NULL;
@ mm/slub.c:1866 @ static void __free_slab(struct kmem_cache *s, struct page *page)
 	__free_pages(page, order);
 }
 
+static void free_delayed(struct list_head *h)
+{
+	while (!list_empty(h)) {
+		struct page *page = list_first_entry(h, struct page, lru);
+
+		list_del(&page->lru);
+		__free_slab(page->slab_cache, page);
+	}
+}
+
 static void rcu_free_slab(struct rcu_head *h)
 {
 	struct page *page = container_of(h, struct page, rcu_head);
@ mm/slub.c:1887 @ static void free_slab(struct kmem_cache *s, struct page *page)
 {
 	if (unlikely(s->flags & SLAB_TYPESAFE_BY_RCU)) {
 		call_rcu(&page->rcu_head, rcu_free_slab);
+	} else if (irqs_disabled()) {
+		struct slub_free_list *f = this_cpu_ptr(&slub_free_list);
+
+		raw_spin_lock(&f->lock);
+		list_add(&page->lru, &f->list);
+		raw_spin_unlock(&f->lock);
 	} else
 		__free_slab(s, page);
 }
@ mm/slub.c:2000 @ static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n,
 	if (!n || !n->nr_partial)
 		return NULL;
 
-	spin_lock(&n->list_lock);
+	raw_spin_lock(&n->list_lock);
 	list_for_each_entry_safe(page, page2, &n->partial, slab_list) {
 		void *t;
 
@ mm/slub.c:2025 @ static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n,
 			break;
 
 	}
-	spin_unlock(&n->list_lock);
+	raw_spin_unlock(&n->list_lock);
 	return object;
 }
 
@ mm/slub.c:2279 @ static void deactivate_slab(struct kmem_cache *s, struct page *page,
 			 * that acquire_slab() will see a slab page that
 			 * is frozen
 			 */
-			spin_lock(&n->list_lock);
+			raw_spin_lock(&n->list_lock);
 		}
 	} else {
 		m = M_FULL;
@ mm/slub.c:2291 @ static void deactivate_slab(struct kmem_cache *s, struct page *page,
 			 * slabs from diagnostic functions will not see
 			 * any frozen slabs.
 			 */
-			spin_lock(&n->list_lock);
+			raw_spin_lock(&n->list_lock);
 		}
 #endif
 	}
@ mm/slub.c:2316 @ static void deactivate_slab(struct kmem_cache *s, struct page *page,
 		goto redo;
 
 	if (lock)
-		spin_unlock(&n->list_lock);
+		raw_spin_unlock(&n->list_lock);
 
 	if (m == M_PARTIAL)
 		stat(s, tail);
@ mm/slub.c:2355 @ static void unfreeze_partials(struct kmem_cache *s,
 		n2 = get_node(s, page_to_nid(page));
 		if (n != n2) {
 			if (n)
-				spin_unlock(&n->list_lock);
+				raw_spin_unlock(&n->list_lock);
 
 			n = n2;
-			spin_lock(&n->list_lock);
+			raw_spin_lock(&n->list_lock);
 		}
 
 		do {
@ mm/slub.c:2387 @ static void unfreeze_partials(struct kmem_cache *s,
 	}
 
 	if (n)
-		spin_unlock(&n->list_lock);
+		raw_spin_unlock(&n->list_lock);
 
 	while (discard_page) {
 		page = discard_page;
@ mm/slub.c:2424 @ static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain)
 			pobjects = oldpage->pobjects;
 			pages = oldpage->pages;
 			if (drain && pobjects > slub_cpu_partial(s)) {
+				struct slub_free_list *f;
 				unsigned long flags;
+				LIST_HEAD(tofree);
 				/*
 				 * partial array is full. Move the existing
 				 * set to the per node partial list.
 				 */
 				local_irq_save(flags);
 				unfreeze_partials(s, this_cpu_ptr(s->cpu_slab));
+				f = this_cpu_ptr(&slub_free_list);
+				raw_spin_lock(&f->lock);
+				list_splice_init(&f->list, &tofree);
+				raw_spin_unlock(&f->lock);
 				local_irq_restore(flags);
+				free_delayed(&tofree);
 				oldpage = NULL;
 				pobjects = 0;
 				pages = 0;
@ mm/slub.c:2506 @ static bool has_cpu_slab(int cpu, void *info)
 
 static void flush_all(struct kmem_cache *s)
 {
+	LIST_HEAD(tofree);
+	int cpu;
+
 	on_each_cpu_cond(has_cpu_slab, flush_cpu_slab, s, 1);
+	for_each_online_cpu(cpu) {
+		struct slub_free_list *f;
+
+		f = &per_cpu(slub_free_list, cpu);
+		raw_spin_lock_irq(&f->lock);
+		list_splice_init(&f->list, &tofree);
+		raw_spin_unlock_irq(&f->lock);
+		free_delayed(&tofree);
+	}
 }
 
 /*
@ mm/slub.c:2573 @ static unsigned long count_partial(struct kmem_cache_node *n,
 	unsigned long x = 0;
 	struct page *page;
 
-	spin_lock_irqsave(&n->list_lock, flags);
+	raw_spin_lock_irqsave(&n->list_lock, flags);
 	list_for_each_entry(page, &n->partial, slab_list)
 		x += get_count(page);
-	spin_unlock_irqrestore(&n->list_lock, flags);
+	raw_spin_unlock_irqrestore(&n->list_lock, flags);
 	return x;
 }
 #endif /* CONFIG_SLUB_DEBUG || CONFIG_SYSFS */
@ mm/slub.c:2715 @ static inline void *get_freelist(struct kmem_cache *s, struct page *page)
  * already disabled (which is the case for bulk allocation).
  */
 static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
-			  unsigned long addr, struct kmem_cache_cpu *c)
+			  unsigned long addr, struct kmem_cache_cpu *c,
+			  struct list_head *to_free)
 {
+	struct slub_free_list *f;
 	void *freelist;
 	struct page *page;
 
@ mm/slub.c:2786 @ static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
 	VM_BUG_ON(!c->page->frozen);
 	c->freelist = get_freepointer(s, freelist);
 	c->tid = next_tid(c->tid);
+
+out:
+	f = this_cpu_ptr(&slub_free_list);
+	raw_spin_lock(&f->lock);
+	list_splice_init(&f->list, to_free);
+	raw_spin_unlock(&f->lock);
+
 	return freelist;
 
 new_slab:
@ mm/slub.c:2808 @ static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
 
 	if (unlikely(!freelist)) {
 		slab_out_of_memory(s, gfpflags, node);
-		return NULL;
+		goto out;
 	}
 
 	page = c->page;
@ mm/slub.c:2821 @ static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
 		goto new_slab;	/* Slab failed checks. Next slab needed */
 
 	deactivate_slab(s, page, get_freepointer(s, freelist), c);
-	return freelist;
+	goto out;
 }
 
 /*
@ mm/slub.c:2833 @ static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
 {
 	void *p;
 	unsigned long flags;
+	LIST_HEAD(tofree);
 
 	local_irq_save(flags);
 #ifdef CONFIG_PREEMPTION
@ mm/slub.c:2845 @ static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
 	c = this_cpu_ptr(s->cpu_slab);
 #endif
 
-	p = ___slab_alloc(s, gfpflags, node, addr, c);
+	p = ___slab_alloc(s, gfpflags, node, addr, c, &tofree);
 	local_irq_restore(flags);
+	free_delayed(&tofree);
 	return p;
 }
 
@ mm/slub.c:2881 @ static __always_inline void *slab_alloc_node(struct kmem_cache *s,
 	unsigned long tid;
 	struct obj_cgroup *objcg = NULL;
 
+	if (IS_ENABLED(CONFIG_PREEMPT_RT) && IS_ENABLED(CONFIG_DEBUG_ATOMIC_SLEEP))
+		WARN_ON_ONCE(!preemptible() &&
+			     (system_state > SYSTEM_BOOTING && system_state < SYSTEM_SUSPEND));
+
 	s = slab_pre_alloc_hook(s, &objcg, 1, gfpflags);
 	if (!s)
 		return NULL;
@ mm/slub.c:3050 @ static void __slab_free(struct kmem_cache *s, struct page *page,
 
 	do {
 		if (unlikely(n)) {
-			spin_unlock_irqrestore(&n->list_lock, flags);
+			raw_spin_unlock_irqrestore(&n->list_lock, flags);
 			n = NULL;
 		}
 		prior = page->freelist;
@ mm/slub.c:3082 @ static void __slab_free(struct kmem_cache *s, struct page *page,
 				 * Otherwise the list_lock will synchronize with
 				 * other processors updating the list of slabs.
 				 */
-				spin_lock_irqsave(&n->list_lock, flags);
+				raw_spin_lock_irqsave(&n->list_lock, flags);
 
 			}
 		}
@ mm/slub.c:3124 @ static void __slab_free(struct kmem_cache *s, struct page *page,
 		add_partial(n, page, DEACTIVATE_TO_TAIL);
 		stat(s, FREE_ADD_PARTIAL);
 	}
-	spin_unlock_irqrestore(&n->list_lock, flags);
+	raw_spin_unlock_irqrestore(&n->list_lock, flags);
 	return;
 
 slab_empty:
@ mm/slub.c:3139 @ static void __slab_free(struct kmem_cache *s, struct page *page,
 		remove_full(s, n, page);
 	}
 
-	spin_unlock_irqrestore(&n->list_lock, flags);
+	raw_spin_unlock_irqrestore(&n->list_lock, flags);
 	stat(s, FREE_SLAB);
 	discard_slab(s, page);
 }
@ mm/slub.c:3349 @ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size,
 			  void **p)
 {
 	struct kmem_cache_cpu *c;
+	LIST_HEAD(to_free);
 	int i;
 	struct obj_cgroup *objcg = NULL;
 
+	if (IS_ENABLED(CONFIG_PREEMPT_RT) && IS_ENABLED(CONFIG_DEBUG_ATOMIC_SLEEP))
+		WARN_ON_ONCE(!preemptible() &&
+			     (system_state > SYSTEM_BOOTING && system_state < SYSTEM_SUSPEND));
+
 	/* memcg and kmem_cache debug support */
 	s = slab_pre_alloc_hook(s, &objcg, size, flags);
 	if (unlikely(!s))
@ mm/slub.c:3387 @ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size,
 			 * of re-populating per CPU c->freelist
 			 */
 			p[i] = ___slab_alloc(s, flags, NUMA_NO_NODE,
-					    _RET_IP_, c);
+					    _RET_IP_, c, &to_free);
 			if (unlikely(!p[i]))
 				goto error;
 
@ mm/slub.c:3402 @ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size,
 	}
 	c->tid = next_tid(c->tid);
 	local_irq_enable();
+	free_delayed(&to_free);
 
 	/* Clear memory outside IRQ disabled fastpath loop */
 	if (unlikely(slab_want_init_on_alloc(flags, s))) {
@ mm/slub.c:3417 @ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size,
 	return i;
 error:
 	local_irq_enable();
+	free_delayed(&to_free);
 	slab_post_alloc_hook(s, objcg, flags, i, p);
 	__kmem_cache_free_bulk(s, i, p);
 	return 0;
@ mm/slub.c:3553 @ static void
 init_kmem_cache_node(struct kmem_cache_node *n)
 {
 	n->nr_partial = 0;
-	spin_lock_init(&n->list_lock);
+	raw_spin_lock_init(&n->list_lock);
 	INIT_LIST_HEAD(&n->partial);
 #ifdef CONFIG_SLUB_DEBUG
 	atomic_long_set(&n->nr_slabs, 0);
@ mm/slub.c:3948 @ static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n)
 	struct page *page, *h;
 
 	BUG_ON(irqs_disabled());
-	spin_lock_irq(&n->list_lock);
+	raw_spin_lock_irq(&n->list_lock);
 	list_for_each_entry_safe(page, h, &n->partial, slab_list) {
 		if (!page->inuse) {
 			remove_partial(n, page);
@ mm/slub.c:3958 @ static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n)
 			  "Objects remaining in %s on __kmem_cache_shutdown()");
 		}
 	}
-	spin_unlock_irq(&n->list_lock);
+	raw_spin_unlock_irq(&n->list_lock);
 
 	list_for_each_entry_safe(page, h, &discard, slab_list)
 		discard_slab(s, page);
@ mm/slub.c:4229 @ int __kmem_cache_shrink(struct kmem_cache *s)
 		for (i = 0; i < SHRINK_PROMOTE_MAX; i++)
 			INIT_LIST_HEAD(promote + i);
 
-		spin_lock_irqsave(&n->list_lock, flags);
+		raw_spin_lock_irqsave(&n->list_lock, flags);
 
 		/*
 		 * Build lists of slabs to discard or promote.
@ mm/slub.c:4260 @ int __kmem_cache_shrink(struct kmem_cache *s)
 		for (i = SHRINK_PROMOTE_MAX - 1; i >= 0; i--)
 			list_splice(promote + i, &n->partial);
 
-		spin_unlock_irqrestore(&n->list_lock, flags);
+		raw_spin_unlock_irqrestore(&n->list_lock, flags);
 
 		/* Release empty slabs */
 		list_for_each_entry_safe(page, t, &discard, slab_list)
@ mm/slub.c:4435 @ void __init kmem_cache_init(void)
 {
 	static __initdata struct kmem_cache boot_kmem_cache,
 		boot_kmem_cache_node;
+	int cpu;
+
+	for_each_possible_cpu(cpu) {
+		raw_spin_lock_init(&per_cpu(slub_free_list, cpu).lock);
+		INIT_LIST_HEAD(&per_cpu(slub_free_list, cpu).list);
+	}
 
 	if (debug_guardpage_minorder())
 		slub_max_order = 0;
@ mm/slub.c:4628 @ static int validate_slab_node(struct kmem_cache *s,
 	struct page *page;
 	unsigned long flags;
 
-	spin_lock_irqsave(&n->list_lock, flags);
+	raw_spin_lock_irqsave(&n->list_lock, flags);
 
 	list_for_each_entry(page, &n->partial, slab_list) {
 		validate_slab(s, page);
@ mm/slub.c:4650 @ static int validate_slab_node(struct kmem_cache *s,
 		       s->name, count, atomic_long_read(&n->nr_slabs));
 
 out:
-	spin_unlock_irqrestore(&n->list_lock, flags);
+	raw_spin_unlock_irqrestore(&n->list_lock, flags);
 	return count;
 }
 
@ mm/slub.c:4701 @ static int alloc_loc_track(struct loc_track *t, unsigned long max, gfp_t flags)
 	struct location *l;
 	int order;
 
+	if (IS_ENABLED(CONFIG_PREEMPT_RT) && flags == GFP_ATOMIC)
+		return 0;
+
 	order = get_order(sizeof(struct location) * max);
 
 	l = (void *)__get_free_pages(flags, order);
@ mm/slub.c:4832 @ static int list_locations(struct kmem_cache *s, char *buf,
 		if (!atomic_long_read(&n->nr_slabs))
 			continue;
 
-		spin_lock_irqsave(&n->list_lock, flags);
+		raw_spin_lock_irqsave(&n->list_lock, flags);
 		list_for_each_entry(page, &n->partial, slab_list)
 			process_slab(&t, s, page, alloc);
 		list_for_each_entry(page, &n->full, slab_list)
 			process_slab(&t, s, page, alloc);
-		spin_unlock_irqrestore(&n->list_lock, flags);
+		raw_spin_unlock_irqrestore(&n->list_lock, flags);
 	}
 
 	for (i = 0; i < t.count; i++) {
@ mm/vmalloc.c:1545 @ static void *new_vmap_block(unsigned int order, gfp_t gfp_mask)
 	struct vmap_block *vb;
 	struct vmap_area *va;
 	unsigned long vb_idx;
-	int node, err;
+	int node, err, cpu;
 	void *vaddr;
 
 	node = numa_node_id();
@ mm/vmalloc.c:1582 @ static void *new_vmap_block(unsigned int order, gfp_t gfp_mask)
 		return ERR_PTR(err);
 	}
 
-	vbq = &get_cpu_var(vmap_block_queue);
+	cpu = get_cpu_light();
+	vbq = this_cpu_ptr(&vmap_block_queue);
 	spin_lock(&vbq->lock);
 	list_add_tail_rcu(&vb->free_list, &vbq->free);
 	spin_unlock(&vbq->lock);
-	put_cpu_var(vmap_block_queue);
+	put_cpu_light();
 
 	return vaddr;
 }
@ mm/vmalloc.c:1652 @ static void *vb_alloc(unsigned long size, gfp_t gfp_mask)
 	struct vmap_block *vb;
 	void *vaddr = NULL;
 	unsigned int order;
+	int cpu;
 
 	BUG_ON(offset_in_page(size));
 	BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC);
@ mm/vmalloc.c:1667 @ static void *vb_alloc(unsigned long size, gfp_t gfp_mask)
 	order = get_order(size);
 
 	rcu_read_lock();
-	vbq = &get_cpu_var(vmap_block_queue);
+	cpu = get_cpu_light();
+	vbq = this_cpu_ptr(&vmap_block_queue);
 	list_for_each_entry_rcu(vb, &vbq->free, free_list) {
 		unsigned long pages_off;
 
@ mm/vmalloc.c:1691 @ static void *vb_alloc(unsigned long size, gfp_t gfp_mask)
 		break;
 	}
 
-	put_cpu_var(vmap_block_queue);
+	put_cpu_light();
 	rcu_read_unlock();
 
 	/* Allocate new block if nothing was found */
@ mm/vmstat.c:324 @ void __mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
 	long x;
 	long t;
 
+	preempt_disable_rt();
 	x = delta + __this_cpu_read(*p);
 
 	t = __this_cpu_read(pcp->stat_threshold);
@ mm/vmstat.c:334 @ void __mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
 		x = 0;
 	}
 	__this_cpu_write(*p, x);
+	preempt_enable_rt();
 }
 EXPORT_SYMBOL(__mod_zone_page_state);
 
@ mm/vmstat.c:351 @ void __mod_node_page_state(struct pglist_data *pgdat, enum node_stat_item item,
 		delta >>= PAGE_SHIFT;
 	}
 
+	preempt_disable_rt();
 	x = delta + __this_cpu_read(*p);
 
 	t = __this_cpu_read(pcp->stat_threshold);
@ mm/vmstat.c:361 @ void __mod_node_page_state(struct pglist_data *pgdat, enum node_stat_item item,
 		x = 0;
 	}
 	__this_cpu_write(*p, x);
+	preempt_enable_rt();
 }
 EXPORT_SYMBOL(__mod_node_page_state);
 
@ mm/vmstat.c:394 @ void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
 	s8 __percpu *p = pcp->vm_stat_diff + item;
 	s8 v, t;
 
+	preempt_disable_rt();
 	v = __this_cpu_inc_return(*p);
 	t = __this_cpu_read(pcp->stat_threshold);
 	if (unlikely(v > t)) {
@ mm/vmstat.c:403 @ void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
 		zone_page_state_add(v + overstep, zone, item);
 		__this_cpu_write(*p, -overstep);
 	}
+	preempt_enable_rt();
 }
 
 void __inc_node_state(struct pglist_data *pgdat, enum node_stat_item item)
@ mm/vmstat.c:414 @ void __inc_node_state(struct pglist_data *pgdat, enum node_stat_item item)
 
 	VM_WARN_ON_ONCE(vmstat_item_in_bytes(item));
 
+	preempt_disable_rt();
 	v = __this_cpu_inc_return(*p);
 	t = __this_cpu_read(pcp->stat_threshold);
 	if (unlikely(v > t)) {
@ mm/vmstat.c:423 @ void __inc_node_state(struct pglist_data *pgdat, enum node_stat_item item)
 		node_page_state_add(v + overstep, pgdat, item);
 		__this_cpu_write(*p, -overstep);
 	}
+	preempt_enable_rt();
 }
 
 void __inc_zone_page_state(struct page *page, enum zone_stat_item item)
@ mm/vmstat.c:444 @ void __dec_zone_state(struct zone *zone, enum zone_stat_item item)
 	s8 __percpu *p = pcp->vm_stat_diff + item;
 	s8 v, t;
 
+	preempt_disable_rt();
 	v = __this_cpu_dec_return(*p);
 	t = __this_cpu_read(pcp->stat_threshold);
 	if (unlikely(v < - t)) {
@ mm/vmstat.c:453 @ void __dec_zone_state(struct zone *zone, enum zone_stat_item item)
 		zone_page_state_add(v - overstep, zone, item);
 		__this_cpu_write(*p, overstep);
 	}
+	preempt_enable_rt();
 }
 
 void __dec_node_state(struct pglist_data *pgdat, enum node_stat_item item)
@ mm/vmstat.c:464 @ void __dec_node_state(struct pglist_data *pgdat, enum node_stat_item item)
 
 	VM_WARN_ON_ONCE(vmstat_item_in_bytes(item));
 
+	preempt_disable_rt();
 	v = __this_cpu_dec_return(*p);
 	t = __this_cpu_read(pcp->stat_threshold);
 	if (unlikely(v < - t)) {
@ mm/vmstat.c:473 @ void __dec_node_state(struct pglist_data *pgdat, enum node_stat_item item)
 		node_page_state_add(v - overstep, pgdat, item);
 		__this_cpu_write(*p, overstep);
 	}
+	preempt_enable_rt();
 }
 
 void __dec_zone_page_state(struct page *page, enum zone_stat_item item)
@ mm/workingset.c:435 @ static struct list_lru shadow_nodes;
 
 void workingset_update_node(struct xa_node *node)
 {
+	struct address_space *mapping;
+
 	/*
 	 * Track non-empty nodes that contain only shadow entries;
 	 * unlink those that contain pages or are being freed.
@ mm/workingset.c:445 @ void workingset_update_node(struct xa_node *node)
 	 * already where they should be. The list_empty() test is safe
 	 * as node->private_list is protected by the i_pages lock.
 	 */
-	VM_WARN_ON_ONCE(!irqs_disabled());  /* For __inc_lruvec_page_state */
+	mapping = container_of(node->array, struct address_space, i_pages);
+	lockdep_assert_held(&mapping->i_pages.xa_lock);
 
 	if (node->count && node->count == node->nr_values) {
 		if (list_empty(&node->private_list)) {
@ mm/z3fold.c:626 @ static inline void add_to_unbuddied(struct z3fold_pool *pool,
 {
 	if (zhdr->first_chunks == 0 || zhdr->last_chunks == 0 ||
 			zhdr->middle_chunks == 0) {
-		struct list_head *unbuddied = get_cpu_ptr(pool->unbuddied);
-
+		struct list_head *unbuddied;
 		int freechunks = num_free_chunks(zhdr);
+
+		migrate_disable();
+		unbuddied = this_cpu_ptr(pool->unbuddied);
 		spin_lock(&pool->lock);
 		list_add(&zhdr->buddy, &unbuddied[freechunks]);
 		spin_unlock(&pool->lock);
 		zhdr->cpu = smp_processor_id();
-		put_cpu_ptr(pool->unbuddied);
+		migrate_enable();
 	}
 }
 
@ mm/z3fold.c:885 @ static inline struct z3fold_header *__z3fold_alloc(struct z3fold_pool *pool,
 	int chunks = size_to_chunks(size), i;
 
 lookup:
+	migrate_disable();
 	/* First, try to find an unbuddied z3fold page. */
-	unbuddied = get_cpu_ptr(pool->unbuddied);
+	unbuddied = this_cpu_ptr(pool->unbuddied);
 	for_each_unbuddied_list(i, chunks) {
 		struct list_head *l = &unbuddied[i];
 
@ mm/z3fold.c:905 @ static inline struct z3fold_header *__z3fold_alloc(struct z3fold_pool *pool,
 		    !z3fold_page_trylock(zhdr)) {
 			spin_unlock(&pool->lock);
 			zhdr = NULL;
-			put_cpu_ptr(pool->unbuddied);
+			migrate_enable();
 			if (can_sleep)
 				cond_resched();
 			goto lookup;
@ mm/z3fold.c:919 @ static inline struct z3fold_header *__z3fold_alloc(struct z3fold_pool *pool,
 		    test_bit(PAGE_CLAIMED, &page->private)) {
 			z3fold_page_unlock(zhdr);
 			zhdr = NULL;
-			put_cpu_ptr(pool->unbuddied);
+			migrate_enable();
 			if (can_sleep)
 				cond_resched();
 			goto lookup;
@ mm/z3fold.c:934 @ static inline struct z3fold_header *__z3fold_alloc(struct z3fold_pool *pool,
 		kref_get(&zhdr->refcount);
 		break;
 	}
-	put_cpu_ptr(pool->unbuddied);
+	migrate_enable();
 
 	if (!zhdr) {
 		int cpu;
@ mm/zsmalloc.c:60 @
 #include <linux/wait.h>
 #include <linux/pagemap.h>
 #include <linux/fs.h>
+#include <linux/local_lock.h>
 
 #define ZSPAGE_MAGIC	0x58
 
@ mm/zsmalloc.c:81 @
 
 #define ZS_HANDLE_SIZE (sizeof(unsigned long))
 
+#ifdef CONFIG_PREEMPT_RT
+
+struct zsmalloc_handle {
+	unsigned long addr;
+	spinlock_t lock;
+};
+
+#define ZS_HANDLE_ALLOC_SIZE (sizeof(struct zsmalloc_handle))
+
+#else
+
+#define ZS_HANDLE_ALLOC_SIZE (sizeof(unsigned long))
+#endif
+
 /*
  * Object location (<PFN>, <obj_idx>) is encoded as
  * a single (unsigned long) handle value.
@ mm/zsmalloc.c:311 @ struct zspage {
 };
 
 struct mapping_area {
+	local_lock_t lock;
 	char *vm_buf; /* copy buffer for objects that span pages */
 	char *vm_addr; /* address of kmap_atomic()'ed pages */
 	enum zs_mapmode vm_mm; /* mapping mode */
@ mm/zsmalloc.c:341 @ static void SetZsPageMovable(struct zs_pool *pool, struct zspage *zspage) {}
 
 static int create_cache(struct zs_pool *pool)
 {
-	pool->handle_cachep = kmem_cache_create("zs_handle", ZS_HANDLE_SIZE,
+	pool->handle_cachep = kmem_cache_create("zs_handle", ZS_HANDLE_ALLOC_SIZE,
 					0, 0, NULL);
 	if (!pool->handle_cachep)
 		return 1;
@ mm/zsmalloc.c:365 @ static void destroy_cache(struct zs_pool *pool)
 
 static unsigned long cache_alloc_handle(struct zs_pool *pool, gfp_t gfp)
 {
-	return (unsigned long)kmem_cache_alloc(pool->handle_cachep,
-			gfp & ~(__GFP_HIGHMEM|__GFP_MOVABLE));
+	void *p;
+
+	p = kmem_cache_alloc(pool->handle_cachep,
+			     gfp & ~(__GFP_HIGHMEM|__GFP_MOVABLE));
+#ifdef CONFIG_PREEMPT_RT
+	if (p) {
+		struct zsmalloc_handle *zh = p;
+
+		spin_lock_init(&zh->lock);
+	}
+#endif
+	return (unsigned long)p;
 }
 
+#ifdef CONFIG_PREEMPT_RT
+static struct zsmalloc_handle *zs_get_pure_handle(unsigned long handle)
+{
+	return (void *)(handle &~((1 << OBJ_TAG_BITS) - 1));
+}
+#endif
+
 static void cache_free_handle(struct zs_pool *pool, unsigned long handle)
 {
 	kmem_cache_free(pool->handle_cachep, (void *)handle);
@ mm/zsmalloc.c:404 @ static void cache_free_zspage(struct zs_pool *pool, struct zspage *zspage)
 
 static void record_obj(unsigned long handle, unsigned long obj)
 {
+#ifdef CONFIG_PREEMPT_RT
+	struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+	WRITE_ONCE(zh->addr, obj);
+#else
 	/*
 	 * lsb of @obj represents handle lock while other bits
 	 * represent object value the handle is pointing so
 	 * updating shouldn't do store tearing.
 	 */
 	WRITE_ONCE(*(unsigned long *)handle, obj);
+#endif
 }
 
 /* zpool driver */
@ mm/zsmalloc.c:497 @ MODULE_ALIAS("zpool-zsmalloc");
 #endif /* CONFIG_ZPOOL */
 
 /* per-cpu VM mapping areas for zspage accesses that cross page boundaries */
-static DEFINE_PER_CPU(struct mapping_area, zs_map_area);
+static DEFINE_PER_CPU(struct mapping_area, zs_map_area) = {
+	/* XXX remove this and use a spin_lock_t in pin_tag() */
+	.lock	= INIT_LOCAL_LOCK(lock),
+};
 
 static bool is_zspage_isolated(struct zspage *zspage)
 {
@ mm/zsmalloc.c:910 @ static unsigned long location_to_obj(struct page *page, unsigned int obj_idx)
 
 static unsigned long handle_to_obj(unsigned long handle)
 {
+#ifdef CONFIG_PREEMPT_RT
+	struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+	return zh->addr;
+#else
 	return *(unsigned long *)handle;
+#endif
 }
 
 static unsigned long obj_to_head(struct page *page, void *obj)
@ mm/zsmalloc.c:930 @ static unsigned long obj_to_head(struct page *page, void *obj)
 
 static inline int testpin_tag(unsigned long handle)
 {
+#ifdef CONFIG_PREEMPT_RT
+	struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+	return spin_is_locked(&zh->lock);
+#else
 	return bit_spin_is_locked(HANDLE_PIN_BIT, (unsigned long *)handle);
+#endif
 }
 
 static inline int trypin_tag(unsigned long handle)
 {
+#ifdef CONFIG_PREEMPT_RT
+	struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+	return spin_trylock(&zh->lock);
+#else
 	return bit_spin_trylock(HANDLE_PIN_BIT, (unsigned long *)handle);
+#endif
 }
 
 static void pin_tag(unsigned long handle) __acquires(bitlock)
 {
+#ifdef CONFIG_PREEMPT_RT
+	struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+	return spin_lock(&zh->lock);
+#else
 	bit_spin_lock(HANDLE_PIN_BIT, (unsigned long *)handle);
+#endif
 }
 
 static void unpin_tag(unsigned long handle) __releases(bitlock)
 {
+#ifdef CONFIG_PREEMPT_RT
+	struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+	return spin_unlock(&zh->lock);
+#else
 	bit_spin_unlock(HANDLE_PIN_BIT, (unsigned long *)handle);
+#endif
 }
 
 static void reset_page(struct page *page)
@ mm/zsmalloc.c:1353 @ void *zs_map_object(struct zs_pool *pool, unsigned long handle,
 	class = pool->size_class[class_idx];
 	off = (class->size * obj_idx) & ~PAGE_MASK;
 
-	area = &get_cpu_var(zs_map_area);
+	local_lock(&zs_map_area.lock);
+	area = this_cpu_ptr(&zs_map_area);
 	area->vm_mm = mm;
 	if (off + class->size <= PAGE_SIZE) {
 		/* this object is contained entirely within a page */
@ mm/zsmalloc.c:1408 @ void zs_unmap_object(struct zs_pool *pool, unsigned long handle)
 
 		__zs_unmap_object(area, pages, off, class->size);
 	}
-	put_cpu_var(zs_map_area);
+	local_unlock(&zs_map_area.lock);
 
 	migrate_read_unlock(zspage);
 	unpin_tag(handle);
@ mm/zswap.c:21 @
 #include <linux/highmem.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
+#include <linux/local_lock.h>
 #include <linux/types.h>
 #include <linux/atomic.h>
 #include <linux/frontswap.h>
@ mm/zswap.c:391 @ static struct zswap_entry *zswap_entry_find_get(struct rb_root *root,
 /*********************************
 * per-cpu code
 **********************************/
-static DEFINE_PER_CPU(u8 *, zswap_dstmem);
+struct zswap_comp {
+	/* Used for per-CPU dstmem and tfm */
+	local_lock_t lock;
+	u8 *dstmem;
+};
+
+static DEFINE_PER_CPU(struct zswap_comp, zswap_comp) = {
+	.lock = INIT_LOCAL_LOCK(lock),
+};
 
 static int zswap_dstmem_prepare(unsigned int cpu)
 {
+	struct zswap_comp *zcomp;
 	u8 *dst;
 
 	dst = kmalloc_node(PAGE_SIZE * 2, GFP_KERNEL, cpu_to_node(cpu));
 	if (!dst)
 		return -ENOMEM;
 
-	per_cpu(zswap_dstmem, cpu) = dst;
+	zcomp = per_cpu_ptr(&zswap_comp, cpu);
+	zcomp->dstmem = dst;
 	return 0;
 }
 
 static int zswap_dstmem_dead(unsigned int cpu)
 {
-	u8 *dst;
+	struct zswap_comp *zcomp;
 
-	dst = per_cpu(zswap_dstmem, cpu);
-	kfree(dst);
-	per_cpu(zswap_dstmem, cpu) = NULL;
+	zcomp = per_cpu_ptr(&zswap_comp, cpu);
+	kfree(zcomp->dstmem);
+	zcomp->dstmem = NULL;
 
 	return 0;
 }
@ mm/zswap.c:933 @ static int zswap_writeback_entry(struct zpool *pool, unsigned long handle)
 		dlen = PAGE_SIZE;
 		src = (u8 *)zhdr + sizeof(struct zswap_header);
 		dst = kmap_atomic(page);
-		tfm = *get_cpu_ptr(entry->pool->tfm);
+		local_lock(&zswap_comp.lock);
+		tfm = *this_cpu_ptr(entry->pool->tfm);
 		ret = crypto_comp_decompress(tfm, src, entry->length,
 					     dst, &dlen);
-		put_cpu_ptr(entry->pool->tfm);
+		local_unlock(&zswap_comp.lock);
 		kunmap_atomic(dst);
 		BUG_ON(ret);
 		BUG_ON(dlen != PAGE_SIZE);
@ mm/zswap.c:1089 @ static int zswap_frontswap_store(unsigned type, pgoff_t offset,
 	}
 
 	/* compress */
-	dst = get_cpu_var(zswap_dstmem);
-	tfm = *get_cpu_ptr(entry->pool->tfm);
+	local_lock(&zswap_comp.lock);
+	dst = *this_cpu_ptr(&zswap_comp.dstmem);
+	tfm = *this_cpu_ptr(entry->pool->tfm);
 	src = kmap_atomic(page);
 	ret = crypto_comp_compress(tfm, src, PAGE_SIZE, dst, &dlen);
 	kunmap_atomic(src);
-	put_cpu_ptr(entry->pool->tfm);
 	if (ret) {
 		ret = -EINVAL;
 		goto put_dstmem;
@ mm/zswap.c:1118 @ static int zswap_frontswap_store(unsigned type, pgoff_t offset,
 	memcpy(buf, &zhdr, hlen);
 	memcpy(buf + hlen, dst, dlen);
 	zpool_unmap_handle(entry->pool->zpool, handle);
-	put_cpu_var(zswap_dstmem);
+	local_unlock(&zswap_comp.lock);
 
 	/* populate entry */
 	entry->offset = offset;
@ mm/zswap.c:1146 @ static int zswap_frontswap_store(unsigned type, pgoff_t offset,
 	return 0;
 
 put_dstmem:
-	put_cpu_var(zswap_dstmem);
+	local_unlock(&zswap_comp.lock);
 	zswap_pool_put(entry->pool);
 freepage:
 	zswap_entry_cache_free(entry);
@ mm/zswap.c:1191 @ static int zswap_frontswap_load(unsigned type, pgoff_t offset,
 	if (zpool_evictable(entry->pool->zpool))
 		src += sizeof(struct zswap_header);
 	dst = kmap_atomic(page);
-	tfm = *get_cpu_ptr(entry->pool->tfm);
+	local_lock(&zswap_comp.lock);
+	tfm = *this_cpu_ptr(entry->pool->tfm);
 	ret = crypto_comp_decompress(tfm, src, entry->length, dst, &dlen);
-	put_cpu_ptr(entry->pool->tfm);
+	local_unlock(&zswap_comp.lock);
 	kunmap_atomic(dst);
 	zpool_unmap_handle(entry->pool->zpool, entry->handle);
 	BUG_ON(ret);
@ net/Kconfig:285 @ config CGROUP_NET_CLASSID
 
 config NET_RX_BUSY_POLL
 	bool
-	default y
+	default y if !PREEMPT_RT
 
 config BQL
 	bool
@ net/core/dev.c:224 @ static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex)
 static inline void rps_lock(struct softnet_data *sd)
 {
 #ifdef CONFIG_RPS
-	spin_lock(&sd->input_pkt_queue.lock);
+	raw_spin_lock(&sd->input_pkt_queue.raw_lock);
 #endif
 }
 
 static inline void rps_unlock(struct softnet_data *sd)
 {
 #ifdef CONFIG_RPS
-	spin_unlock(&sd->input_pkt_queue.lock);
+	raw_spin_unlock(&sd->input_pkt_queue.raw_lock);
 #endif
 }
 
@ net/core/dev.c:3053 @ static void __netif_reschedule(struct Qdisc *q)
 	sd->output_queue_tailp = &q->next_sched;
 	raise_softirq_irqoff(NET_TX_SOFTIRQ);
 	local_irq_restore(flags);
+	preempt_check_resched_rt();
 }
 
 void __netif_schedule(struct Qdisc *q)
@ net/core/dev.c:3116 @ void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason)
 	__this_cpu_write(softnet_data.completion_queue, skb);
 	raise_softirq_irqoff(NET_TX_SOFTIRQ);
 	local_irq_restore(flags);
+	preempt_check_resched_rt();
 }
 EXPORT_SYMBOL(__dev_kfree_skb_irq);
 
@ net/core/dev.c:3791 @ static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
 	 * This permits qdisc->running owner to get the lock more
 	 * often and dequeue packets faster.
 	 */
+#ifdef CONFIG_PREEMPT_RT
+	contended = true;
+#else
 	contended = qdisc_is_running(q);
+#endif
 	if (unlikely(contended))
 		spin_lock(&q->busylock);
 
@ net/core/dev.c:4594 @ static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
 	rps_unlock(sd);
 
 	local_irq_restore(flags);
+	preempt_check_resched_rt();
 
 	atomic_long_inc(&skb->dev->rx_dropped);
 	kfree_skb(skb);
@ net/core/dev.c:4810 @ static int netif_rx_internal(struct sk_buff *skb)
 		struct rps_dev_flow voidflow, *rflow = &voidflow;
 		int cpu;
 
-		preempt_disable();
+		migrate_disable();
 		rcu_read_lock();
 
 		cpu = get_rps_cpu(skb->dev, skb, &rflow);
@ net/core/dev.c:4820 @ static int netif_rx_internal(struct sk_buff *skb)
 		ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
 
 		rcu_read_unlock();
-		preempt_enable();
+		migrate_enable();
 	} else
 #endif
 	{
 		unsigned int qtail;
 
-		ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
-		put_cpu();
+		ret = enqueue_to_backlog(skb, get_cpu_light(), &qtail);
+		put_cpu_light();
 	}
 	return ret;
 }
@ net/core/dev.c:4866 @ int netif_rx_ni(struct sk_buff *skb)
 
 	trace_netif_rx_ni_entry(skb);
 
-	preempt_disable();
+	local_bh_disable();
 	err = netif_rx_internal(skb);
-	if (local_softirq_pending())
-		do_softirq();
-	preempt_enable();
+	local_bh_enable();
 	trace_netif_rx_ni_exit(err);
 
 	return err;
@ net/core/dev.c:6344 @ static void net_rps_action_and_irq_enable(struct softnet_data *sd)
 		sd->rps_ipi_list = NULL;
 
 		local_irq_enable();
+		preempt_check_resched_rt();
 
 		/* Send pending IPI's to kick RPS processing on remote cpus. */
 		net_rps_send_ipi(remsd);
 	} else
 #endif
 		local_irq_enable();
+	preempt_check_resched_rt();
 }
 
 static bool sd_has_rps_ipi_waiting(struct softnet_data *sd)
@ net/core/dev.c:6429 @ void __napi_schedule(struct napi_struct *n)
 	local_irq_save(flags);
 	____napi_schedule(this_cpu_ptr(&softnet_data), n);
 	local_irq_restore(flags);
+	preempt_check_resched_rt();
 }
 EXPORT_SYMBOL(__napi_schedule);
 
@ net/core/dev.c:10974 @ static int dev_cpu_dead(unsigned int oldcpu)
 
 	raise_softirq_irqoff(NET_TX_SOFTIRQ);
 	local_irq_enable();
+	preempt_check_resched_rt();
 
 #ifdef CONFIG_RPS
 	remsd = oldsd->rps_ipi_list;
@ net/core/dev.c:10988 @ static int dev_cpu_dead(unsigned int oldcpu)
 		netif_rx_ni(skb);
 		input_queue_head_incr(oldsd);
 	}
-	while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) {
+	while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) {
 		netif_rx_ni(skb);
 		input_queue_head_incr(oldsd);
 	}
@ net/core/dev.c:11304 @ static int __init net_dev_init(void)
 
 		INIT_WORK(flush, flush_backlog);
 
-		skb_queue_head_init(&sd->input_pkt_queue);
+		skb_queue_head_init_raw(&sd->input_pkt_queue);
 		skb_queue_head_init(&sd->process_queue);
 #ifdef CONFIG_XFRM_OFFLOAD
 		skb_queue_head_init(&sd->xfrm_backlog);
@ net/core/gen_estimator.c:45 @
 struct net_rate_estimator {
 	struct gnet_stats_basic_packed	*bstats;
 	spinlock_t		*stats_lock;
-	seqcount_t		*running;
+	net_seqlock_t		*running;
 	struct gnet_stats_basic_cpu __percpu *cpu_bstats;
 	u8			ewma_log;
 	u8			intvl_log; /* period : (250ms << intvl_log) */
@ net/core/gen_estimator.c:128 @ int gen_new_estimator(struct gnet_stats_basic_packed *bstats,
 		      struct gnet_stats_basic_cpu __percpu *cpu_bstats,
 		      struct net_rate_estimator __rcu **rate_est,
 		      spinlock_t *lock,
-		      seqcount_t *running,
+		      net_seqlock_t *running,
 		      struct nlattr *opt)
 {
 	struct gnet_estimator *parm = nla_data(opt);
@ net/core/gen_estimator.c:229 @ int gen_replace_estimator(struct gnet_stats_basic_packed *bstats,
 			  struct gnet_stats_basic_cpu __percpu *cpu_bstats,
 			  struct net_rate_estimator __rcu **rate_est,
 			  spinlock_t *lock,
-			  seqcount_t *running, struct nlattr *opt)
+			  net_seqlock_t *running, struct nlattr *opt)
 {
 	return gen_new_estimator(bstats, cpu_bstats, rate_est,
 				 lock, running, opt);
@ net/core/gen_stats.c:140 @ __gnet_stats_copy_basic_cpu(struct gnet_stats_basic_packed *bstats,
 }
 
 void
-__gnet_stats_copy_basic(const seqcount_t *running,
+__gnet_stats_copy_basic(net_seqlock_t *running,
 			struct gnet_stats_basic_packed *bstats,
 			struct gnet_stats_basic_cpu __percpu *cpu,
 			struct gnet_stats_basic_packed *b)
@ net/core/gen_stats.c:153 @ __gnet_stats_copy_basic(const seqcount_t *running,
 	}
 	do {
 		if (running)
-			seq = read_seqcount_begin(running);
+			seq = net_seq_begin(running);
 		bstats->bytes = b->bytes;
 		bstats->packets = b->packets;
-	} while (running && read_seqcount_retry(running, seq));
+	} while (running && net_seq_retry(running, seq));
 }
 EXPORT_SYMBOL(__gnet_stats_copy_basic);
 
 static int
-___gnet_stats_copy_basic(const seqcount_t *running,
+___gnet_stats_copy_basic(net_seqlock_t *running,
 			 struct gnet_dump *d,
 			 struct gnet_stats_basic_cpu __percpu *cpu,
 			 struct gnet_stats_basic_packed *b,
@ net/core/gen_stats.c:207 @ ___gnet_stats_copy_basic(const seqcount_t *running,
  * if the room in the socket buffer was not sufficient.
  */
 int
-gnet_stats_copy_basic(const seqcount_t *running,
+gnet_stats_copy_basic(net_seqlock_t *running,
 		      struct gnet_dump *d,
 		      struct gnet_stats_basic_cpu __percpu *cpu,
 		      struct gnet_stats_basic_packed *b)
@ net/core/gen_stats.c:231 @ EXPORT_SYMBOL(gnet_stats_copy_basic);
  * if the room in the socket buffer was not sufficient.
  */
 int
-gnet_stats_copy_basic_hw(const seqcount_t *running,
+gnet_stats_copy_basic_hw(net_seqlock_t *running,
 			 struct gnet_dump *d,
 			 struct gnet_stats_basic_cpu __percpu *cpu,
 			 struct gnet_stats_basic_packed *b)
@ net/core/sock.c:3059 @ void lock_sock_nested(struct sock *sk, int subclass)
 	if (sk->sk_lock.owned)
 		__lock_sock(sk);
 	sk->sk_lock.owned = 1;
-	spin_unlock(&sk->sk_lock.slock);
+	spin_unlock_bh(&sk->sk_lock.slock);
 	/*
 	 * The sk_lock has mutex_lock() semantics here:
 	 */
 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
-	local_bh_enable();
 }
 EXPORT_SYMBOL(lock_sock_nested);
 
@ net/core/sock.c:3112 @ bool lock_sock_fast(struct sock *sk)
 
 	__lock_sock(sk);
 	sk->sk_lock.owned = 1;
-	spin_unlock(&sk->sk_lock.slock);
+	spin_unlock_bh(&sk->sk_lock.slock);
 	/*
 	 * The sk_lock has mutex_lock() semantics here:
 	 */
 	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
-	local_bh_enable();
 	return true;
 }
 EXPORT_SYMBOL(lock_sock_fast);
@ net/ipv4/inet_hashtables.c:640 @ int __inet_hash(struct sock *sk, struct sock *osk)
 	int err = 0;
 
 	if (sk->sk_state != TCP_LISTEN) {
+		local_bh_disable();
 		inet_ehash_nolisten(sk, osk, NULL);
+		local_bh_enable();
 		return 0;
 	}
 	WARN_ON(!sk_unhashed(sk));
@ net/ipv4/inet_hashtables.c:674 @ int inet_hash(struct sock *sk)
 {
 	int err = 0;
 
-	if (sk->sk_state != TCP_CLOSE) {
-		local_bh_disable();
+	if (sk->sk_state != TCP_CLOSE)
 		err = __inet_hash(sk, NULL);
-		local_bh_enable();
-	}
 
 	return err;
 }
@ net/ipv4/inet_hashtables.c:686 @ void inet_unhash(struct sock *sk)
 	struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo;
 	struct inet_listen_hashbucket *ilb = NULL;
 	spinlock_t *lock;
+	bool state_listen;
 
 	if (sk_unhashed(sk))
 		return;
 
 	if (sk->sk_state == TCP_LISTEN) {
+		state_listen = true;
 		ilb = &hashinfo->listening_hash[inet_sk_listen_hashfn(sk)];
-		lock = &ilb->lock;
+		spin_lock(&ilb->lock);
 	} else {
+		state_listen = false;
 		lock = inet_ehash_lockp(hashinfo, sk->sk_hash);
+		spin_lock_bh(lock);
 	}
-	spin_lock_bh(lock);
 	if (sk_unhashed(sk))
 		goto unlock;
 
@ net/ipv4/inet_hashtables.c:712 @ void inet_unhash(struct sock *sk)
 	__sk_nulls_del_node_init_rcu(sk);
 	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
 unlock:
-	spin_unlock_bh(lock);
+	if (state_listen)
+		spin_unlock(&ilb->lock);
+	else
+		spin_unlock_bh(lock);
 }
 EXPORT_SYMBOL_GPL(inet_unhash);
 
@ net/ipv6/inet6_hashtables.c:336 @ int inet6_hash(struct sock *sk)
 {
 	int err = 0;
 
-	if (sk->sk_state != TCP_CLOSE) {
-		local_bh_disable();
+	if (sk->sk_state != TCP_CLOSE)
 		err = __inet_hash(sk, NULL);
-		local_bh_enable();
-	}
 
 	return err;
 }
@ net/sched/sch_api.c:1267 @ static struct Qdisc *qdisc_create(struct net_device *dev,
 		rcu_assign_pointer(sch->stab, stab);
 	}
 	if (tca[TCA_RATE]) {
-		seqcount_t *running;
+		net_seqlock_t *running;
 
 		err = -EOPNOTSUPP;
 		if (sch->flags & TCQ_F_MQROOT) {
@ net/sched/sch_generic.c:581 @ struct Qdisc noop_qdisc = {
 	.ops		=	&noop_qdisc_ops,
 	.q.lock		=	__SPIN_LOCK_UNLOCKED(noop_qdisc.q.lock),
 	.dev_queue	=	&noop_netdev_queue,
+#ifdef CONFIG_PREEMPT_RT
+	.running	=	__SEQLOCK_UNLOCKED(noop_qdisc.running),
+#else
 	.running	=	SEQCNT_ZERO(noop_qdisc.running),
+#endif
 	.busylock	=	__SPIN_LOCK_UNLOCKED(noop_qdisc.busylock),
 	.gso_skb = {
 		.next = (struct sk_buff *)&noop_qdisc.gso_skb,
@ net/sched/sch_generic.c:896 @ struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
 	lockdep_set_class(&sch->seqlock,
 			  dev->qdisc_tx_busylock ?: &qdisc_tx_busylock);
 
+#ifdef CONFIG_PREEMPT_RT
+	seqlock_init(&sch->running);
+	lockdep_set_class(&sch->running.lock,
+			  dev->qdisc_running_key ?: &qdisc_running_key);
+#else
 	seqcount_init(&sch->running);
 	lockdep_set_class(&sch->running,
 			  dev->qdisc_running_key ?: &qdisc_running_key);
+#endif
 
 	sch->ops = ops;
 	sch->flags = ops->static_flags;
@ net/sunrpc/svc_xprt.c:425 @ void svc_xprt_do_enqueue(struct svc_xprt *xprt)
 	if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags))
 		return;
 
-	cpu = get_cpu();
+	cpu = get_cpu_light();
 	pool = svc_pool_for_cpu(xprt->xpt_server, cpu);
 
 	atomic_long_inc(&pool->sp_stats.packets);
@ net/sunrpc/svc_xprt.c:449 @ void svc_xprt_do_enqueue(struct svc_xprt *xprt)
 	rqstp = NULL;
 out_unlock:
 	rcu_read_unlock();
-	put_cpu();
+	put_cpu_light();
 	trace_svc_xprt_do_enqueue(xprt, rqstp);
 }
 EXPORT_SYMBOL_GPL(svc_xprt_do_enqueue);
@ net/xfrm/xfrm_state.c:2676 @ int __net_init xfrm_state_init(struct net *net)
 	net->xfrm.state_num = 0;
 	INIT_WORK(&net->xfrm.state_hash_work, xfrm_hash_resize);
 	spin_lock_init(&net->xfrm.xfrm_state_lock);
-	seqcount_init(&net->xfrm.xfrm_state_hash_generation);
+	seqcount_spinlock_init(&net->xfrm.xfrm_state_hash_generation,
+			       &net->xfrm.xfrm_state_lock);
 	return 0;
 
 out_byspi: