Index: linux-3.12.19-rt30/Documentation/hwlat_detector.txt =================================================================== @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:4 @ +Introduction: +------------- + +The module hwlat_detector is a special purpose kernel module that is used to +detect large system latencies induced by the behavior of certain underlying +hardware or firmware, independent of Linux itself. The code was developed +originally to detect SMIs (System Management Interrupts) on x86 systems, +however there is nothing x86 specific about this patchset. It was +originally written for use by the "RT" patch since the Real Time +kernel is highly latency sensitive. + +SMIs are usually not serviced by the Linux kernel, which typically does not +even know that they are occuring. SMIs are instead are set up by BIOS code +and are serviced by BIOS code, usually for "critical" events such as +management of thermal sensors and fans. Sometimes though, SMIs are used for +other tasks and those tasks can spend an inordinate amount of time in the +handler (sometimes measured in milliseconds). Obviously this is a problem if +you are trying to keep event service latencies down in the microsecond range. + +The hardware latency detector works by hogging all of the cpus for configurable +amounts of time (by calling stop_machine()), polling the CPU Time Stamp Counter +for some period, then looking for gaps in the TSC data. Any gap indicates a +time when the polling was interrupted and since the machine is stopped and +interrupts turned off the only thing that could do that would be an SMI. + +Note that the SMI detector should *NEVER* be used in a production environment. +It is intended to be run manually to determine if the hardware platform has a +problem with long system firmware service routines. + +Usage: +------ + +Loading the module hwlat_detector passing the parameter "enabled=1" (or by +setting the "enable" entry in "hwlat_detector" debugfs toggled on) is the only +step required to start the hwlat_detector. It is possible to redefine the +threshold in microseconds (us) above which latency spikes will be taken +into account (parameter "threshold="). + +Example: + + # modprobe hwlat_detector enabled=1 threshold=100 + +After the module is loaded, it creates a directory named "hwlat_detector" under +the debugfs mountpoint, "/debug/hwlat_detector" for this text. It is necessary +to have debugfs mounted, which might be on /sys/debug on your system. + +The /debug/hwlat_detector interface contains the following files: + +count - number of latency spikes observed since last reset +enable - a global enable/disable toggle (0/1), resets count +max - maximum hardware latency actually observed (usecs) +sample - a pipe from which to read current raw sample data + in the format <timestamp> <latency observed usecs> + (can be opened O_NONBLOCK for a single sample) +threshold - minimum latency value to be considered (usecs) +width - time period to sample with CPUs held (usecs) + must be less than the total window size (enforced) +window - total period of sampling, width being inside (usecs) + +By default we will set width to 500,000 and window to 1,000,000, meaning that +we will sample every 1,000,000 usecs (1s) for 500,000 usecs (0.5s). If we +observe any latencies that exceed the threshold (initially 100 usecs), +then we write to a global sample ring buffer of 8K samples, which is +consumed by reading from the "sample" (pipe) debugfs file interface. Index: linux-3.12.19-rt30/Documentation/sysrq.txt =================================================================== --- linux-3.12.19-rt30.orig/Documentation/sysrq.txt +++ linux-3.12.19-rt30/Documentation/sysrq.txt @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:60 @ On PowerPC - Press 'ALT - Print Screen ( On other - If you know of the key combos for other architectures, please let me know so I can add them to this section. -On all - write a character to /proc/sysrq-trigger. e.g.: - +On all - write a character to /proc/sysrq-trigger, e.g.: echo t > /proc/sysrq-trigger +On all - Enable network SysRq by writing a cookie to icmp_echo_sysrq, e.g. + echo 0x01020304 >/proc/sys/net/ipv4/icmp_echo_sysrq + Send an ICMP echo request with this pattern plus the particular + SysRq command key. Example: + # ping -c1 -s57 -p0102030468 + will trigger the SysRq-H (help) command. + + * What are the 'command' keys? ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 'b' - Will immediately reboot the system without syncing or unmounting Index: linux-3.12.19-rt30/Documentation/trace/histograms.txt =================================================================== --- /dev/null +++ linux-3.12.19-rt30/Documentation/trace/histograms.txt @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:4 @ + Using the Linux Kernel Latency Histograms + + +This document gives a short explanation how to enable, configure and use +latency histograms. Latency histograms are primarily relevant in the +context of real-time enabled kernels (CONFIG_PREEMPT/CONFIG_PREEMPT_RT) +and are used in the quality management of the Linux real-time +capabilities. + + +* Purpose of latency histograms + +A latency histogram continuously accumulates the frequencies of latency +data. There are two types of histograms +- potential sources of latencies +- effective latencies + + +* Potential sources of latencies + +Potential sources of latencies are code segments where interrupts, +preemption or both are disabled (aka critical sections). To create +histograms of potential sources of latency, the kernel stores the time +stamp at the start of a critical section, determines the time elapsed +when the end of the section is reached, and increments the frequency +counter of that latency value - irrespective of whether any concurrently +running process is affected by latency or not. +- Configuration items (in the Kernel hacking/Tracers submenu) + CONFIG_INTERRUPT_OFF_LATENCY + CONFIG_PREEMPT_OFF_LATENCY + + +* Effective latencies + +Effective latencies are actually occuring during wakeup of a process. To +determine effective latencies, the kernel stores the time stamp when a +process is scheduled to be woken up, and determines the duration of the +wakeup time shortly before control is passed over to this process. Note +that the apparent latency in user space may be somewhat longer, since the +process may be interrupted after control is passed over to it but before +the execution in user space takes place. Simply measuring the interval +between enqueuing and wakeup may also not appropriate in cases when a +process is scheduled as a result of a timer expiration. The timer may have +missed its deadline, e.g. due to disabled interrupts, but this latency +would not be registered. Therefore, the offsets of missed timers are +recorded in a separate histogram. If both wakeup latency and missed timer +offsets are configured and enabled, a third histogram may be enabled that +records the overall latency as a sum of the timer latency, if any, and the +wakeup latency. This histogram is called "timerandwakeup". +- Configuration items (in the Kernel hacking/Tracers submenu) + CONFIG_WAKEUP_LATENCY + CONFIG_MISSED_TIMER_OFSETS + + +* Usage + +The interface to the administration of the latency histograms is located +in the debugfs file system. To mount it, either enter + +mount -t sysfs nodev /sys +mount -t debugfs nodev /sys/kernel/debug + +from shell command line level, or add + +nodev /sys sysfs defaults 0 0 +nodev /sys/kernel/debug debugfs defaults 0 0 + +to the file /etc/fstab. All latency histogram related files are then +available in the directory /sys/kernel/debug/tracing/latency_hist. A +particular histogram type is enabled by writing non-zero to the related +variable in the /sys/kernel/debug/tracing/latency_hist/enable directory. +Select "preemptirqsoff" for the histograms of potential sources of +latencies and "wakeup" for histograms of effective latencies etc. The +histogram data - one per CPU - are available in the files + +/sys/kernel/debug/tracing/latency_hist/preemptoff/CPUx +/sys/kernel/debug/tracing/latency_hist/irqsoff/CPUx +/sys/kernel/debug/tracing/latency_hist/preemptirqsoff/CPUx +/sys/kernel/debug/tracing/latency_hist/wakeup/CPUx +/sys/kernel/debug/tracing/latency_hist/wakeup/sharedprio/CPUx +/sys/kernel/debug/tracing/latency_hist/missed_timer_offsets/CPUx +/sys/kernel/debug/tracing/latency_hist/timerandwakeup/CPUx + +The histograms are reset by writing non-zero to the file "reset" in a +particular latency directory. To reset all latency data, use + +#!/bin/sh + +TRACINGDIR=/sys/kernel/debug/tracing +HISTDIR=$TRACINGDIR/latency_hist + +if test -d $HISTDIR +then + cd $HISTDIR + for i in `find . | grep /reset$` + do + echo 1 >$i + done +fi + + +* Data format + +Latency data are stored with a resolution of one microsecond. The +maximum latency is 10,240 microseconds. The data are only valid, if the +overflow register is empty. Every output line contains the latency in +microseconds in the first row and the number of samples in the second +row. To display only lines with a positive latency count, use, for +example, + +grep -v " 0$" /sys/kernel/debug/tracing/latency_hist/preemptoff/CPU0 + +#Minimum latency: 0 microseconds. +#Average latency: 0 microseconds. +#Maximum latency: 25 microseconds. +#Total samples: 3104770694 +#There are 0 samples greater or equal than 10240 microseconds +#usecs samples + 0 2984486876 + 1 49843506 + 2 58219047 + 3 5348126 + 4 2187960 + 5 3388262 + 6 959289 + 7 208294 + 8 40420 + 9 4485 + 10 14918 + 11 18340 + 12 25052 + 13 19455 + 14 5602 + 15 969 + 16 47 + 17 18 + 18 14 + 19 1 + 20 3 + 21 2 + 22 5 + 23 2 + 25 1 + + +* Wakeup latency of a selected process + +To only collect wakeup latency data of a particular process, write the +PID of the requested process to + +/sys/kernel/debug/tracing/latency_hist/wakeup/pid + +PIDs are not considered, if this variable is set to 0. + + +* Details of the process with the highest wakeup latency so far + +Selected data of the process that suffered from the highest wakeup +latency that occurred in a particular CPU are available in the file + +/sys/kernel/debug/tracing/latency_hist/wakeup/max_latency-CPUx. + +In addition, other relevant system data at the time when the +latency occurred are given. + +The format of the data is (all in one line): +<PID> <Priority> <Latency> (<Timeroffset>) <Command> \ +<- <PID> <Priority> <Command> <Timestamp> + +The value of <Timeroffset> is only relevant in the combined timer +and wakeup latency recording. In the wakeup recording, it is +always 0, in the missed_timer_offsets recording, it is the same +as <Latency>. + +When retrospectively searching for the origin of a latency and +tracing was not enabled, it may be helpful to know the name and +some basic data of the task that (finally) was switching to the +late real-tlme task. In addition to the victim's data, also the +data of the possible culprit are therefore displayed after the +"<-" symbol. + +Finally, the timestamp of the time when the latency occurred +in <seconds>.<microseconds> after the most recent system boot +is provided. + +These data are also reset when the wakeup histogram is reset. Index: linux-3.12.19-rt30/arch/Kconfig =================================================================== --- linux-3.12.19-rt30.orig/arch/Kconfig +++ linux-3.12.19-rt30/arch/Kconfig @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:9 @ config OPROFILE tristate "OProfile system profiling" depends on PROFILING depends on HAVE_OPROFILE + depends on !PREEMPT_RT_FULL select RING_BUFFER select RING_BUFFER_ALLOW_SWAP help Index: linux-3.12.19-rt30/arch/alpha/mm/fault.c =================================================================== --- linux-3.12.19-rt30.orig/arch/alpha/mm/fault.c +++ linux-3.12.19-rt30/arch/alpha/mm/fault.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:110 @ do_page_fault(unsigned long address, uns /* If we're in an interrupt context, or have no user context, we must not take the fault. */ - if (!mm || in_atomic()) + if (!mm || pagefault_disabled()) goto no_context; #ifdef CONFIG_ALPHA_LARGE_VMALLOC Index: linux-3.12.19-rt30/arch/arm/Kconfig =================================================================== --- linux-3.12.19-rt30.orig/arch/arm/Kconfig +++ linux-3.12.19-rt30/arch/arm/Kconfig @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:55 @ config ARM select HAVE_MOD_ARCH_SPECIFIC if ARM_UNWIND select HAVE_OPROFILE if (HAVE_PERF_EVENTS) select HAVE_PERF_EVENTS + select HAVE_PREEMPT_LAZY select HAVE_REGS_AND_STACK_ACCESS_API select HAVE_SYSCALL_TRACEPOINTS select HAVE_UID16 Index: linux-3.12.19-rt30/arch/arm/include/asm/switch_to.h =================================================================== --- linux-3.12.19-rt30.orig/arch/arm/include/asm/switch_to.h +++ linux-3.12.19-rt30/arch/arm/include/asm/switch_to.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:6 @ #include <linux/thread_info.h> +#if defined CONFIG_PREEMPT_RT_FULL && defined CONFIG_HIGHMEM +void switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p); +#else +static inline void +switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p) { } +#endif + /* * For v7 SMP cores running a preemptible kernel we may be pre-empted * during a TLB maintenance operation, so execute an inner-shareable dsb @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:32 @ extern struct task_struct *__switch_to(s #define switch_to(prev,next,last) \ do { \ + switch_kmaps(prev, next); \ last = __switch_to(prev,task_thread_info(prev), task_thread_info(next)); \ } while (0) Index: linux-3.12.19-rt30/arch/arm/include/asm/thread_info.h =================================================================== --- linux-3.12.19-rt30.orig/arch/arm/include/asm/thread_info.h +++ linux-3.12.19-rt30/arch/arm/include/asm/thread_info.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:63 @ struct arm_restart_block { 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 */ struct exec_domain *exec_domain; /* execution domain */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:163 @ extern int vfp_restore_user_hwstate(stru #define TIF_SIGPENDING 0 #define TIF_NEED_RESCHED 1 #define TIF_NOTIFY_RESUME 2 /* callback before returning to user */ +#define TIF_NEED_RESCHED_LAZY 3 #define TIF_SYSCALL_TRACE 8 #define TIF_SYSCALL_AUDIT 9 #define TIF_SYSCALL_TRACEPOINT 10 @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:176 @ extern int vfp_restore_user_hwstate(stru #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_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) #define _TIF_SYSCALL_TRACEPOINT (1 << TIF_SYSCALL_TRACEPOINT) Index: linux-3.12.19-rt30/arch/arm/kernel/asm-offsets.c =================================================================== --- linux-3.12.19-rt30.orig/arch/arm/kernel/asm-offsets.c +++ linux-3.12.19-rt30/arch/arm/kernel/asm-offsets.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:57 @ 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_EXEC_DOMAIN, offsetof(struct thread_info, exec_domain)); Index: linux-3.12.19-rt30/arch/arm/kernel/entry-armv.S =================================================================== --- linux-3.12.19-rt30.orig/arch/arm/kernel/entry-armv.S +++ linux-3.12.19-rt30/arch/arm/kernel/entry-armv.S @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:208 @ __irq_svc: #ifdef CONFIG_PREEMPT get_thread_info tsk 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 @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:234 @ 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 moveq pc, r8 @ go again b 1b #endif Index: linux-3.12.19-rt30/arch/arm/kernel/process.c =================================================================== --- linux-3.12.19-rt30.orig/arch/arm/kernel/process.c +++ linux-3.12.19-rt30/arch/arm/kernel/process.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:437 @ unsigned long arch_randomize_brk(struct } #ifdef CONFIG_MMU +/* + * CONFIG_SPLIT_PTLOCK_CPUS results in a page->ptl lock. If the lock is not + * initialized by pgtable_page_ctor() then a coredump of the vector page will + * fail. + */ +static int __init vectors_user_mapping_init_page(void) +{ + struct page *page; + unsigned long addr = 0xffff0000; + pgd_t *pgd; + pud_t *pud; + pmd_t *pmd; + + pgd = pgd_offset_k(addr); + pud = pud_offset(pgd, addr); + pmd = pmd_offset(pud, addr); + page = pmd_page(*(pmd)); + + pgtable_page_ctor(page); + + return 0; +} +late_initcall(vectors_user_mapping_init_page); + #ifdef CONFIG_KUSER_HELPERS /* * The vectors page is always readable from user space for the Index: linux-3.12.19-rt30/arch/arm/kernel/signal.c =================================================================== --- linux-3.12.19-rt30.orig/arch/arm/kernel/signal.c +++ linux-3.12.19-rt30/arch/arm/kernel/signal.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:592 @ asmlinkage int do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall) { 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))) Index: linux-3.12.19-rt30/arch/arm/kernel/unwind.c =================================================================== --- linux-3.12.19-rt30.orig/arch/arm/kernel/unwind.c +++ linux-3.12.19-rt30/arch/arm/kernel/unwind.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:90 @ extern const struct unwind_idx __start_u static const struct unwind_idx *__origin_unwind_idx; extern const struct unwind_idx __stop_unwind_idx[]; -static DEFINE_SPINLOCK(unwind_lock); +static DEFINE_RAW_SPINLOCK(unwind_lock); static LIST_HEAD(unwind_tables); /* Convert a prel31 symbol to an absolute address */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:198 @ static const struct unwind_idx *unwind_f /* module unwind tables */ struct unwind_table *table; - spin_lock_irqsave(&unwind_lock, flags); + raw_spin_lock_irqsave(&unwind_lock, flags); list_for_each_entry(table, &unwind_tables, list) { if (addr >= table->begin_addr && addr < table->end_addr) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:210 @ static const struct unwind_idx *unwind_f break; } } - spin_unlock_irqrestore(&unwind_lock, flags); + raw_spin_unlock_irqrestore(&unwind_lock, flags); } pr_debug("%s: idx = %p\n", __func__, idx); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:472 @ struct unwind_table *unwind_table_add(un tab->begin_addr = text_addr; tab->end_addr = text_addr + text_size; - spin_lock_irqsave(&unwind_lock, flags); + raw_spin_lock_irqsave(&unwind_lock, flags); list_add_tail(&tab->list, &unwind_tables); - spin_unlock_irqrestore(&unwind_lock, flags); + raw_spin_unlock_irqrestore(&unwind_lock, flags); return tab; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:486 @ void unwind_table_del(struct unwind_tabl if (!tab) return; - spin_lock_irqsave(&unwind_lock, flags); + raw_spin_lock_irqsave(&unwind_lock, flags); list_del(&tab->list); - spin_unlock_irqrestore(&unwind_lock, flags); + raw_spin_unlock_irqrestore(&unwind_lock, flags); kfree(tab); } Index: linux-3.12.19-rt30/arch/arm/mach-at91/at91rm9200_time.c =================================================================== --- linux-3.12.19-rt30.orig/arch/arm/mach-at91/at91rm9200_time.c +++ linux-3.12.19-rt30/arch/arm/mach-at91/at91rm9200_time.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:137 @ clkevt32k_mode(enum clock_event_mode mod break; case CLOCK_EVT_MODE_SHUTDOWN: case CLOCK_EVT_MODE_UNUSED: + remove_irq(NR_IRQS_LEGACY + AT91_ID_SYS, &at91rm9200_timer_irq); case CLOCK_EVT_MODE_RESUME: irqmask = 0; break; Index: linux-3.12.19-rt30/arch/arm/mach-at91/at91sam926x_time.c =================================================================== --- linux-3.12.19-rt30.orig/arch/arm/mach-at91/at91sam926x_time.c +++ linux-3.12.19-rt30/arch/arm/mach-at91/at91sam926x_time.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:80 @ static struct clocksource pit_clk = { .flags = CLOCK_SOURCE_IS_CONTINUOUS, }; - +static struct irqaction at91sam926x_pit_irq; /* * Clockevent device: interrupts every 1/HZ (== pit_cycles * MCK/16) */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:89 @ pit_clkevt_mode(enum clock_event_mode mo { switch (mode) { case CLOCK_EVT_MODE_PERIODIC: + /* Set up irq handler */ + setup_irq(at91sam926x_pit_irq.irq, &at91sam926x_pit_irq); /* update clocksource counter */ pit_cnt += pit_cycle * PIT_PICNT(pit_read(AT91_PIT_PIVR)); pit_write(AT91_PIT_MR, (pit_cycle - 1) | AT91_PIT_PITEN @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:103 @ pit_clkevt_mode(enum clock_event_mode mo case CLOCK_EVT_MODE_UNUSED: /* disable irq, leaving the clocksource active */ pit_write(AT91_PIT_MR, (pit_cycle - 1) | AT91_PIT_PITEN); + remove_irq(at91sam926x_pit_irq.irq, &at91sam926x_pit_irq); break; case CLOCK_EVT_MODE_RESUME: break; Index: linux-3.12.19-rt30/arch/arm/mach-exynos/platsmp.c =================================================================== --- linux-3.12.19-rt30.orig/arch/arm/mach-exynos/platsmp.c +++ linux-3.12.19-rt30/arch/arm/mach-exynos/platsmp.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:76 @ static void __iomem *scu_base_addr(void) return (void __iomem *)(S5P_VA_SCU); } -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); static void exynos_secondary_init(unsigned int cpu) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:89 @ static void exynos_secondary_init(unsign /* * Synchronise with the boot thread. */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); } static int exynos_boot_secondary(unsigned int cpu, struct task_struct *idle) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:102 @ static int exynos_boot_secondary(unsigne * Set synchronisation state between this boot processor * and the secondary one */ - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); /* * The secondary processor is waiting to be released from @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:131 @ static int exynos_boot_secondary(unsigne if (timeout == 0) { printk(KERN_ERR "cpu1 power enable failed"); - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return -ETIMEDOUT; } } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:170 @ static int exynos_boot_secondary(unsigne * now the secondary core is starting up let it run its * calibrations, then wait for it to finish */ - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return pen_release != -1 ? -ENOSYS : 0; } Index: linux-3.12.19-rt30/arch/arm/mach-msm/platsmp.c =================================================================== --- linux-3.12.19-rt30.orig/arch/arm/mach-msm/platsmp.c +++ linux-3.12.19-rt30/arch/arm/mach-msm/platsmp.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:33 @ extern void msm_secondary_startup(void); -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); static inline int get_core_count(void) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:53 @ static void msm_secondary_init(unsigned /* * Synchronise with the boot thread. */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); } static void prepare_cold_cpu(unsigned int cpu) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:91 @ static int msm_boot_secondary(unsigned i * set synchronisation state between this boot processor * and the secondary one */ - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); /* * The secondary processor is waiting to be released from @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:125 @ static int msm_boot_secondary(unsigned i * now the secondary core is starting up let it run its * calibrations, then wait for it to finish */ - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return pen_release != -1 ? -ENOSYS : 0; } Index: linux-3.12.19-rt30/arch/arm/mach-omap2/omap-smp.c =================================================================== --- linux-3.12.19-rt30.orig/arch/arm/mach-omap2/omap-smp.c +++ linux-3.12.19-rt30/arch/arm/mach-omap2/omap-smp.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:47 @ u16 pm44xx_errata; /* SCU base address */ static void __iomem *scu_base; -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); void __iomem *omap4_get_scu_base(void) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:71 @ static void omap4_secondary_init(unsigne /* * Synchronise with the boot thread. */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); } static int omap4_boot_secondary(unsigned int cpu, struct task_struct *idle) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:86 @ static int omap4_boot_secondary(unsigned * Set synchronisation state between this boot processor * and the secondary one */ - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); /* * Update the AuxCoreBoot0 with boot state for secondary core. @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:163 @ static int omap4_boot_secondary(unsigned * Now the secondary core is starting up let it run its * calibrations, then wait for it to finish */ - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return 0; } Index: linux-3.12.19-rt30/arch/arm/mach-prima2/platsmp.c =================================================================== --- linux-3.12.19-rt30.orig/arch/arm/mach-prima2/platsmp.c +++ linux-3.12.19-rt30/arch/arm/mach-prima2/platsmp.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:26 @ static void __iomem *scu_base; static void __iomem *rsc_base; -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); static struct map_desc scu_io_desc __initdata = { .length = SZ_4K, @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:59 @ static void sirfsoc_secondary_init(unsig /* * Synchronise with the boot thread. */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); } static struct of_device_id rsc_ids[] = { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:98 @ static int sirfsoc_boot_secondary(unsign /* make sure write buffer is drained */ mb(); - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); /* * The secondary processor is waiting to be released from @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:131 @ static int sirfsoc_boot_secondary(unsign * now the secondary core is starting up let it run its * calibrations, then wait for it to finish */ - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return pen_release != -1 ? -ENOSYS : 0; } Index: linux-3.12.19-rt30/arch/arm/mach-spear/platsmp.c =================================================================== --- linux-3.12.19-rt30.orig/arch/arm/mach-spear/platsmp.c +++ linux-3.12.19-rt30/arch/arm/mach-spear/platsmp.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:23 @ #include <mach/spear.h> #include "generic.h" -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); static void __iomem *scu_base = IOMEM(VA_SCU_BASE); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:39 @ static void spear13xx_secondary_init(uns /* * Synchronise with the boot thread. */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); } static int spear13xx_boot_secondary(unsigned int cpu, struct task_struct *idle) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:51 @ static int spear13xx_boot_secondary(unsi * set synchronisation state between this boot processor * and the secondary one */ - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); /* * The secondary processor is waiting to be released from @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:78 @ static int spear13xx_boot_secondary(unsi * now the secondary core is starting up let it run its * calibrations, then wait for it to finish */ - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return pen_release != -1 ? -ENOSYS : 0; } Index: linux-3.12.19-rt30/arch/arm/mach-sti/platsmp.c =================================================================== --- linux-3.12.19-rt30.orig/arch/arm/mach-sti/platsmp.c +++ linux-3.12.19-rt30/arch/arm/mach-sti/platsmp.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:38 @ static void write_pen_release(int val) outer_clean_range(__pa(&pen_release), __pa(&pen_release + 1)); } -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); void sti_secondary_init(unsigned int cpu) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:53 @ void sti_secondary_init(unsigned int cpu /* * Synchronise with the boot thread. */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); } int sti_boot_secondary(unsigned int cpu, struct task_struct *idle) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:65 @ int sti_boot_secondary(unsigned int cpu, * set synchronisation state between this boot processor * and the secondary one */ - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); /* * The secondary processor is waiting to be released from @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:96 @ int sti_boot_secondary(unsigned int cpu, * now the secondary core is starting up let it run its * calibrations, then wait for it to finish */ - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return pen_release != -1 ? -ENOSYS : 0; } Index: linux-3.12.19-rt30/arch/arm/mach-ux500/platsmp.c =================================================================== --- linux-3.12.19-rt30.orig/arch/arm/mach-ux500/platsmp.c +++ linux-3.12.19-rt30/arch/arm/mach-ux500/platsmp.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:55 @ static void __iomem *scu_base_addr(void) return NULL; } -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); static void ux500_secondary_init(unsigned int cpu) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:68 @ static void ux500_secondary_init(unsigne /* * Synchronise with the boot thread. */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); } static int ux500_boot_secondary(unsigned int cpu, struct task_struct *idle) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:80 @ static int ux500_boot_secondary(unsigned * set synchronisation state between this boot processor * and the secondary one */ - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); /* * The secondary processor is waiting to be released from @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:101 @ static int ux500_boot_secondary(unsigned * now the secondary core is starting up let it run its * calibrations, then wait for it to finish */ - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return pen_release != -1 ? -ENOSYS : 0; } Index: linux-3.12.19-rt30/arch/arm/mm/fault.c =================================================================== --- linux-3.12.19-rt30.orig/arch/arm/mm/fault.c +++ linux-3.12.19-rt30/arch/arm/mm/fault.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:280 @ do_page_fault(unsigned long addr, unsign * If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm) + if (!mm || pagefault_disabled()) goto no_context; if (user_mode(regs)) Index: linux-3.12.19-rt30/arch/arm/mm/highmem.c =================================================================== --- linux-3.12.19-rt30.orig/arch/arm/mm/highmem.c +++ linux-3.12.19-rt30/arch/arm/mm/highmem.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:41 @ EXPORT_SYMBOL(kunmap); void *kmap_atomic(struct page *page) { + pte_t pte = mk_pte(page, kmap_prot); unsigned int idx; unsigned long vaddr; void *kmap; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:80 @ void *kmap_atomic(struct page *page) * in place, so the contained TLB flush ensures the TLB is updated * with the new mapping. */ - set_top_pte(vaddr, mk_pte(page, kmap_prot)); +#ifdef CONFIG_PREEMPT_RT_FULL + current->kmap_pte[type] = pte; +#endif + set_top_pte(vaddr, pte); return (void *)vaddr; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:100 @ void __kunmap_atomic(void *kvaddr) if (cache_is_vivt()) __cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE); +#ifdef CONFIG_PREEMPT_RT_FULL + current->kmap_pte[type] = __pte(0); +#endif #ifdef CONFIG_DEBUG_HIGHMEM BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx)); - set_top_pte(vaddr, __pte(0)); #else (void) idx; /* to kill a warning */ #endif + set_top_pte(vaddr, __pte(0)); kmap_atomic_idx_pop(); } else if (vaddr >= PKMAP_ADDR(0) && vaddr < PKMAP_ADDR(LAST_PKMAP)) { /* this address was obtained through kmap_high_get() */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:120 @ EXPORT_SYMBOL(__kunmap_atomic); void *kmap_atomic_pfn(unsigned long pfn) { + pte_t pte = pfn_pte(pfn, kmap_prot); unsigned long vaddr; int idx, type; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:132 @ void *kmap_atomic_pfn(unsigned long pfn) #ifdef CONFIG_DEBUG_HIGHMEM BUG_ON(!pte_none(get_top_pte(vaddr))); #endif - set_top_pte(vaddr, pfn_pte(pfn, kmap_prot)); +#ifdef CONFIG_PREEMPT_RT_FULL + current->kmap_pte[type] = pte; +#endif + set_top_pte(vaddr, pte); return (void *)vaddr; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:149 @ struct page *kmap_atomic_to_page(const v return pte_page(get_top_pte(vaddr)); } + +#if defined CONFIG_PREEMPT_RT_FULL +void switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p) +{ + int i; + + /* + * Clear @prev's kmap_atomic mappings + */ + for (i = 0; i < prev_p->kmap_idx; i++) { + int idx = i + KM_TYPE_NR * smp_processor_id(); + + set_top_pte(__fix_to_virt(FIX_KMAP_BEGIN + idx), __pte(0)); + } + /* + * Restore @next_p's kmap_atomic mappings + */ + for (i = 0; i < next_p->kmap_idx; i++) { + int idx = i + KM_TYPE_NR * smp_processor_id(); + + if (!pte_none(next_p->kmap_pte[i])) + set_top_pte(__fix_to_virt(FIX_KMAP_BEGIN + idx), + next_p->kmap_pte[i]); + } +} +#endif Index: linux-3.12.19-rt30/arch/arm/plat-versatile/platsmp.c =================================================================== --- linux-3.12.19-rt30.orig/arch/arm/plat-versatile/platsmp.c +++ linux-3.12.19-rt30/arch/arm/plat-versatile/platsmp.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:34 @ static void write_pen_release(int val) outer_clean_range(__pa(&pen_release), __pa(&pen_release + 1)); } -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); void versatile_secondary_init(unsigned int cpu) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:47 @ void versatile_secondary_init(unsigned i /* * Synchronise with the boot thread. */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); } int versatile_boot_secondary(unsigned int cpu, struct task_struct *idle) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:59 @ int versatile_boot_secondary(unsigned in * Set synchronisation state between this boot processor * and the secondary one */ - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); /* * This is really belt and braces; we hold unintended secondary @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:89 @ int versatile_boot_secondary(unsigned in * now the secondary core is starting up let it run its * calibrations, then wait for it to finish */ - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return pen_release != -1 ? -ENOSYS : 0; } Index: linux-3.12.19-rt30/arch/avr32/mm/fault.c =================================================================== --- linux-3.12.19-rt30.orig/arch/avr32/mm/fault.c +++ linux-3.12.19-rt30/arch/avr32/mm/fault.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:84 @ asmlinkage void do_page_fault(unsigned l * If we're in an interrupt or have no user context, we must * not take the fault... */ - if (in_atomic() || !mm || regs->sr & SYSREG_BIT(GM)) + if (!mm || regs->sr & SYSREG_BIT(GM) || pagefault_disabled()) goto no_context; local_irq_enable(); Index: linux-3.12.19-rt30/arch/cris/mm/fault.c =================================================================== --- linux-3.12.19-rt30.orig/arch/cris/mm/fault.c +++ linux-3.12.19-rt30/arch/cris/mm/fault.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:116 @ do_page_fault(unsigned long address, str * user context, we must not take the fault. */ - if (in_atomic() || !mm) + if (!mm || pagefault_disabled()) goto no_context; if (user_mode(regs)) Index: linux-3.12.19-rt30/arch/frv/mm/fault.c =================================================================== --- linux-3.12.19-rt30.orig/arch/frv/mm/fault.c +++ linux-3.12.19-rt30/arch/frv/mm/fault.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:81 @ asmlinkage void do_page_fault(int datamm * If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm) + if (!mm || pagefault_disabled()) goto no_context; if (user_mode(__frame)) Index: linux-3.12.19-rt30/arch/ia64/mm/fault.c =================================================================== --- linux-3.12.19-rt30.orig/arch/ia64/mm/fault.c +++ linux-3.12.19-rt30/arch/ia64/mm/fault.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:99 @ ia64_do_page_fault (unsigned long addres /* * If we're in an interrupt or have no user context, we must not take the fault.. */ - if (in_atomic() || !mm) + if (!mm || pagefault_disabled()) goto no_context; #ifdef CONFIG_VIRTUAL_MEM_MAP Index: linux-3.12.19-rt30/arch/m32r/mm/fault.c =================================================================== --- linux-3.12.19-rt30.orig/arch/m32r/mm/fault.c +++ linux-3.12.19-rt30/arch/m32r/mm/fault.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:117 @ asmlinkage void do_page_fault(struct pt_ * If we're in an interrupt or have no user context or are running in an * atomic region then we must not take the fault.. */ - if (in_atomic() || !mm) + if (!mm || pagefault_disabled()) goto bad_area_nosemaphore; if (error_code & ACE_USERMODE) Index: linux-3.12.19-rt30/arch/m68k/mm/fault.c =================================================================== --- linux-3.12.19-rt30.orig/arch/m68k/mm/fault.c +++ linux-3.12.19-rt30/arch/m68k/mm/fault.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:88 @ int do_page_fault(struct pt_regs *regs, * If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm) + if (!mm || pagefault_disabled()) goto no_context; if (user_mode(regs)) Index: linux-3.12.19-rt30/arch/microblaze/mm/fault.c =================================================================== --- linux-3.12.19-rt30.orig/arch/microblaze/mm/fault.c +++ linux-3.12.19-rt30/arch/microblaze/mm/fault.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:110 @ void do_page_fault(struct pt_regs *regs, if ((error_code & 0x13) == 0x13 || (error_code & 0x11) == 0x11) is_write = 0; - if (unlikely(in_atomic() || !mm)) { + if (unlikely(!mm || pagefault_disabled())) { if (kernel_mode(regs)) goto bad_area_nosemaphore; Index: linux-3.12.19-rt30/arch/mips/Kconfig =================================================================== --- linux-3.12.19-rt30.orig/arch/mips/Kconfig +++ linux-3.12.19-rt30/arch/mips/Kconfig @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2081 @ config CPU_R4400_WORKAROUNDS # config HIGHMEM bool "High Memory Support" - depends on 32BIT && CPU_SUPPORTS_HIGHMEM && SYS_SUPPORTS_HIGHMEM + depends on 32BIT && CPU_SUPPORTS_HIGHMEM && SYS_SUPPORTS_HIGHMEM && !PREEMPT_RT_FULL config CPU_SUPPORTS_HIGHMEM bool Index: linux-3.12.19-rt30/arch/mips/kernel/signal.c =================================================================== --- linux-3.12.19-rt30.orig/arch/mips/kernel/signal.c +++ linux-3.12.19-rt30/arch/mips/kernel/signal.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:576 @ asmlinkage void do_notify_resume(struct __u32 thread_info_flags) { local_irq_enable(); + preempt_check_resched(); user_exit(); Index: linux-3.12.19-rt30/arch/mips/mm/fault.c =================================================================== --- linux-3.12.19-rt30.orig/arch/mips/mm/fault.c +++ linux-3.12.19-rt30/arch/mips/mm/fault.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:92 @ static void __kprobes __do_page_fault(st * If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm) + if (!mm || pagefault_disabled()) goto bad_area_nosemaphore; if (user_mode(regs)) Index: linux-3.12.19-rt30/arch/mn10300/mm/fault.c =================================================================== --- linux-3.12.19-rt30.orig/arch/mn10300/mm/fault.c +++ linux-3.12.19-rt30/arch/mn10300/mm/fault.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:171 @ asmlinkage void do_page_fault(struct pt_ * If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm) + if (!mm || pagefault_disabled()) goto no_context; if ((fault_code & MMUFCR_xFC_ACCESS) == MMUFCR_xFC_ACCESS_USR) Index: linux-3.12.19-rt30/arch/parisc/mm/fault.c =================================================================== --- linux-3.12.19-rt30.orig/arch/parisc/mm/fault.c +++ linux-3.12.19-rt30/arch/parisc/mm/fault.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:180 @ void do_page_fault(struct pt_regs *regs, int fault; unsigned int flags; - if (in_atomic()) + if (pagefault_disabled()) goto no_context; tsk = current; Index: linux-3.12.19-rt30/arch/powerpc/Kconfig =================================================================== --- linux-3.12.19-rt30.orig/arch/powerpc/Kconfig +++ linux-3.12.19-rt30/arch/powerpc/Kconfig @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:63 @ config LOCKDEP_SUPPORT config RWSEM_GENERIC_SPINLOCK bool + default y if PREEMPT_RT_FULL config RWSEM_XCHGADD_ALGORITHM bool - default y + default y if !PREEMPT_RT_FULL config GENERIC_LOCKBREAK bool @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:135 @ config PPC select GENERIC_CLOCKEVENTS select GENERIC_STRNCPY_FROM_USER select GENERIC_STRNLEN_USER + select HAVE_PREEMPT_LAZY select HAVE_MOD_ARCH_SPECIFIC select MODULES_USE_ELF_RELA select CLONE_BACKWARDS @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:291 @ menu "Kernel options" config HIGHMEM bool "High memory support" - depends on PPC32 + depends on PPC32 && !PREEMPT_RT_FULL source kernel/Kconfig.hz source kernel/Kconfig.preempt Index: linux-3.12.19-rt30/arch/powerpc/include/asm/thread_info.h =================================================================== --- linux-3.12.19-rt30.orig/arch/powerpc/include/asm/thread_info.h +++ linux-3.12.19-rt30/arch/powerpc/include/asm/thread_info.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:46 @ struct thread_info { int cpu; /* cpu we're on */ int preempt_count; /* 0 => preemptable, <0 => BUG */ + int preempt_lazy_count; /* 0 => preemptable, + <0 => BUG */ struct restart_block restart_block; unsigned long local_flags; /* private flags for thread */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:95 @ static inline struct thread_info *curren #define TIF_SYSCALL_TRACE 0 /* syscall trace active */ #define TIF_SIGPENDING 1 /* signal pending */ #define TIF_NEED_RESCHED 2 /* rescheduling necessary */ -#define TIF_POLLING_NRFLAG 3 /* true if poll_idle() is polling - TIF_NEED_RESCHED */ +#define TIF_NEED_RESCHED_LAZY 3 /* lazy rescheduling necessary */ #define TIF_32BIT 4 /* 32 bit binary */ #define TIF_PERFMON_WORK 5 /* work for pfm_handle_work() */ #define TIF_PERFMON_CTXSW 6 /* perfmon needs ctxsw calls */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:111 @ static inline struct thread_info *curren #define TIF_EMULATE_STACK_STORE 16 /* Is an instruction emulation for stack store? */ #define TIF_MEMDIE 17 /* is terminating due to OOM killer */ +#define TIF_POLLING_NRFLAG 18 /* true if poll_idle() is polling + TIF_NEED_RESCHED */ /* as above, but as bit values */ #define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:132 @ static inline struct thread_info *curren #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_T_OR_A (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \ _TIF_SECCOMP | _TIF_SYSCALL_TRACEPOINT | \ _TIF_NOHZ) #define _TIF_USER_WORK_MASK (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \ - _TIF_NOTIFY_RESUME | _TIF_UPROBE) + _TIF_NOTIFY_RESUME | _TIF_UPROBE | \ + _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 */ Index: linux-3.12.19-rt30/arch/powerpc/kernel/asm-offsets.c =================================================================== --- linux-3.12.19-rt30.orig/arch/powerpc/kernel/asm-offsets.c +++ linux-3.12.19-rt30/arch/powerpc/kernel/asm-offsets.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:168 @ int main(void) DEFINE(TI_FLAGS, offsetof(struct thread_info, flags)); DEFINE(TI_LOCAL_FLAGS, offsetof(struct thread_info, local_flags)); DEFINE(TI_PREEMPT, offsetof(struct thread_info, preempt_count)); + DEFINE(TI_PREEMPT_LAZY, offsetof(struct thread_info, preempt_lazy_count)); DEFINE(TI_TASK, offsetof(struct thread_info, task)); DEFINE(TI_CPU, offsetof(struct thread_info, cpu)); Index: linux-3.12.19-rt30/arch/powerpc/kernel/entry_32.S =================================================================== --- linux-3.12.19-rt30.orig/arch/powerpc/kernel/entry_32.S +++ linux-3.12.19-rt30/arch/powerpc/kernel/entry_32.S @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:893 @ resume_kernel: cmpwi 0,r0,0 /* if non-zero, just restore regs and return */ bne restore andi. r8,r8,_TIF_NEED_RESCHED + bne+ 1f + lwz r0,TI_PREEMPT_LAZY(r9) + cmpwi 0,r0,0 /* if non-zero, just restore regs and return */ + bne restore + lwz r0,TI_FLAGS(r9) + andi. r0,r0,_TIF_NEED_RESCHED_LAZY beq+ restore +1: lwz r3,_MSR(r1) andi. r0,r3,MSR_EE /* interrupts off? */ beq restore /* don't schedule if so */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:911 @ resume_kernel: */ bl trace_hardirqs_off #endif -1: bl preempt_schedule_irq +2: bl preempt_schedule_irq CURRENT_THREAD_INFO(r9, r1) lwz r3,TI_FLAGS(r9) - andi. r0,r3,_TIF_NEED_RESCHED - bne- 1b + andi. r0,r3,_TIF_NEED_RESCHED_MASK + bne- 2b #ifdef CONFIG_TRACE_IRQFLAGS /* And now, to properly rebalance the above, we tell lockdep they * are being turned back on, which will happen when we return @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1236 @ 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 */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1257 @ recheck: MTMSRD(r10) /* disable interrupts */ CURRENT_THREAD_INFO(r9, r1) lwz r9,TI_FLAGS(r9) - 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 Index: linux-3.12.19-rt30/arch/powerpc/kernel/entry_64.S =================================================================== --- linux-3.12.19-rt30.orig/arch/powerpc/kernel/entry_64.S +++ linux-3.12.19-rt30/arch/powerpc/kernel/entry_64.S @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:662 @ _GLOBAL(ret_from_except_lite) #else beq restore #endif -1: andi. r0,r4,_TIF_NEED_RESCHED +1: andi. r0,r4,_TIF_NEED_RESCHED_MASK beq 2f bl .restore_interrupts SCHEDULE_USER @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:712 @ resume_kernel: #ifdef CONFIG_PREEMPT /* 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 cr1,r8,0 ld r0,SOFTE(r1) cmpdi r0,0 @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:740 @ resume_kernel: /* Re-test flags and eventually loop */ CURRENT_THREAD_INFO(r9, r1) ld r4,TI_FLAGS(r9) - andi. r0,r4,_TIF_NEED_RESCHED + andi. r0,r4,_TIF_NEED_RESCHED_MASK bne 1b /* Index: linux-3.12.19-rt30/arch/powerpc/kernel/irq.c =================================================================== --- linux-3.12.19-rt30.orig/arch/powerpc/kernel/irq.c +++ linux-3.12.19-rt30/arch/powerpc/kernel/irq.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:597 @ void irq_ctx_init(void) } } +#ifndef CONFIG_PREEMPT_RT_FULL static inline void do_softirq_onstack(void) { struct thread_info *curtp, *irqtp; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:630 @ void do_softirq(void) local_irq_restore(flags); } +#endif irq_hw_number_t virq_to_hw(unsigned int virq) { Index: linux-3.12.19-rt30/arch/powerpc/kernel/misc_32.S =================================================================== --- linux-3.12.19-rt30.orig/arch/powerpc/kernel/misc_32.S +++ linux-3.12.19-rt30/arch/powerpc/kernel/misc_32.S @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:43 @ * We store the saved ksp_limit in the unused part * of the STACK_FRAME_OVERHEAD */ +#ifndef CONFIG_PREEMPT_RT_FULL _GLOBAL(call_do_softirq) mflr r0 stw r0,4(r1) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:60 @ _GLOBAL(call_do_softirq) stw r10,THREAD+KSP_LIMIT(r2) mtlr r0 blr +#endif /* * void call_do_irq(struct pt_regs *regs, struct thread_info *irqtp); Index: linux-3.12.19-rt30/arch/powerpc/kernel/misc_64.S =================================================================== --- linux-3.12.19-rt30.orig/arch/powerpc/kernel/misc_64.S +++ linux-3.12.19-rt30/arch/powerpc/kernel/misc_64.S @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:32 @ .text +#ifndef CONFIG_PREEMPT_RT_FULL _GLOBAL(call_do_softirq) mflr r0 std r0,16(r1) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:43 @ _GLOBAL(call_do_softirq) ld r0,16(r1) mtlr r0 blr +#endif _GLOBAL(call_do_irq) mflr r0 Index: linux-3.12.19-rt30/arch/powerpc/kernel/time.c =================================================================== --- linux-3.12.19-rt30.orig/arch/powerpc/kernel/time.c +++ linux-3.12.19-rt30/arch/powerpc/kernel/time.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:426 @ unsigned long profile_pc(struct pt_regs EXPORT_SYMBOL(profile_pc); #endif -#ifdef CONFIG_IRQ_WORK +#if defined(CONFIG_IRQ_WORK) && !defined(CONFIG_PREEMPT_RT_FULL) /* * 64-bit uses a byte in the PACA, 32-bit uses a per-cpu variable... Index: linux-3.12.19-rt30/arch/powerpc/mm/fault.c =================================================================== --- linux-3.12.19-rt30.orig/arch/powerpc/mm/fault.c +++ linux-3.12.19-rt30/arch/powerpc/mm/fault.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:264 @ int __kprobes do_page_fault(struct pt_re if (!arch_irq_disabled_regs(regs)) local_irq_enable(); - if (in_atomic() || mm == NULL) { + if (in_atomic() || mm == NULL || pagefault_disabled()) { if (!user_mode(regs)) { rc = SIGSEGV; goto bail; Index: linux-3.12.19-rt30/arch/powerpc/platforms/52xx/mpc52xx_pic.c =================================================================== --- linux-3.12.19-rt30.orig/arch/powerpc/platforms/52xx/mpc52xx_pic.c +++ linux-3.12.19-rt30/arch/powerpc/platforms/52xx/mpc52xx_pic.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:343 @ static int mpc52xx_irqhost_map(struct ir { int l1irq; int l2irq; - struct irq_chip *irqchip; + struct irq_chip *uninitialized_var(irqchip); void *hndlr; int type; u32 reg; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:376 @ static int mpc52xx_irqhost_map(struct ir case MPC52xx_IRQ_L1_PERP: irqchip = &mpc52xx_periph_irqchip; break; case MPC52xx_IRQ_L1_SDMA: irqchip = &mpc52xx_sdma_irqchip; break; case MPC52xx_IRQ_L1_CRIT: - default: pr_warn("%s: Critical IRQ #%d is unsupported! Nopping it.\n", - __func__, l1irq); + __func__, l2irq); irq_set_chip(virq, &no_irq_chip); return 0; } Index: linux-3.12.19-rt30/arch/s390/mm/fault.c =================================================================== --- linux-3.12.19-rt30.orig/arch/s390/mm/fault.c +++ linux-3.12.19-rt30/arch/s390/mm/fault.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:299 @ static inline int do_exception(struct pt * user context. */ fault = VM_FAULT_BADCONTEXT; - if (unlikely(!user_space_fault(trans_exc_code) || in_atomic() || !mm)) + if (unlikely(!user_space_fault(trans_exc_code) || + !mm || pagefault_disabled())) goto out; address = trans_exc_code & __FAIL_ADDR_MASK; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:446 @ void __kprobes do_asce_exception(struct clear_tsk_thread_flag(current, TIF_PER_TRAP); trans_exc_code = regs->int_parm_long; - if (unlikely(!user_space_fault(trans_exc_code) || in_atomic() || !mm)) + if (unlikely(!user_space_fault(trans_exc_code) || !mm || + pagefault_disabled())) goto no_context; down_read(&mm->mmap_sem); Index: linux-3.12.19-rt30/arch/score/mm/fault.c =================================================================== --- linux-3.12.19-rt30.orig/arch/score/mm/fault.c +++ linux-3.12.19-rt30/arch/score/mm/fault.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:76 @ asmlinkage void do_page_fault(struct pt_ * If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm) + if (!mm || pagefault_disabled()) goto bad_area_nosemaphore; if (user_mode(regs)) Index: linux-3.12.19-rt30/arch/sh/kernel/irq.c =================================================================== --- linux-3.12.19-rt30.orig/arch/sh/kernel/irq.c +++ linux-3.12.19-rt30/arch/sh/kernel/irq.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:152 @ void irq_ctx_exit(int cpu) hardirq_ctx[cpu] = NULL; } +#ifndef CONFIG_PREEMPT_RT_FULL asmlinkage void do_softirq(void) { unsigned long flags; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:195 @ asmlinkage void do_softirq(void) local_irq_restore(flags); } +#endif #else static inline void handle_one_irq(unsigned int irq) { Index: linux-3.12.19-rt30/arch/sh/mm/fault.c =================================================================== --- linux-3.12.19-rt30.orig/arch/sh/mm/fault.c +++ linux-3.12.19-rt30/arch/sh/mm/fault.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:441 @ asmlinkage void __kprobes do_page_fault( * If we're in an interrupt, have no user context or are running * in an atomic region then we must not take the fault: */ - if (unlikely(in_atomic() || !mm)) { + if (unlikely(!mm || pagefault_disabled())) { bad_area_nosemaphore(regs, error_code, address); return; } Index: linux-3.12.19-rt30/arch/sparc/Kconfig =================================================================== --- linux-3.12.19-rt30.orig/arch/sparc/Kconfig +++ linux-3.12.19-rt30/arch/sparc/Kconfig @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:29 @ config SPARC select HAVE_DMA_ATTRS select HAVE_DMA_API_DEBUG select HAVE_ARCH_JUMP_LABEL if SPARC64 + select IRQ_FORCED_THREADING select GENERIC_IRQ_SHOW select ARCH_WANT_IPC_PARSE_VERSION select USE_GENERIC_SMP_HELPERS if SMP @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:182 @ config NR_CPUS source kernel/Kconfig.hz config RWSEM_GENERIC_SPINLOCK - bool - default y if SPARC32 + def_bool PREEMPT_RT_FULL config RWSEM_XCHGADD_ALGORITHM - bool - default y if SPARC64 + def_bool !RWSEM_GENERIC_SPINLOCK && !PREEMPT_RT_FULL config GENERIC_HWEIGHT bool @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:526 @ menu "Executable file formats" source "fs/Kconfig.binfmt" +config EARLY_PRINTK + bool + default y + config COMPAT bool depends on SPARC64 Index: linux-3.12.19-rt30/arch/sparc/include/asm/mmu_64.h =================================================================== --- linux-3.12.19-rt30.orig/arch/sparc/include/asm/mmu_64.h +++ linux-3.12.19-rt30/arch/sparc/include/asm/mmu_64.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:93 @ struct tsb_config { #endif typedef struct { - spinlock_t lock; + raw_spinlock_t lock; unsigned long sparc64_ctx_val; unsigned long huge_pte_count; struct page *pgtable_page; Index: linux-3.12.19-rt30/arch/sparc/include/asm/mmu_context_64.h =================================================================== --- linux-3.12.19-rt30.orig/arch/sparc/include/asm/mmu_context_64.h +++ linux-3.12.19-rt30/arch/sparc/include/asm/mmu_context_64.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:16 @ static inline void enter_lazy_tlb(struct { } -extern spinlock_t ctx_alloc_lock; +extern raw_spinlock_t ctx_alloc_lock; extern unsigned long tlb_context_cache; extern unsigned long mmu_context_bmap[]; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:80 @ static inline void switch_mm(struct mm_s if (unlikely(mm == &init_mm)) return; - spin_lock_irqsave(&mm->context.lock, flags); + raw_spin_lock_irqsave(&mm->context.lock, flags); ctx_valid = CTX_VALID(mm->context); if (!ctx_valid) get_new_mmu_context(mm); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:128 @ static inline void switch_mm(struct mm_s __flush_tlb_mm(CTX_HWBITS(mm->context), SECONDARY_CONTEXT); } - spin_unlock_irqrestore(&mm->context.lock, flags); + raw_spin_unlock_irqrestore(&mm->context.lock, flags); } #define deactivate_mm(tsk,mm) do { } while (0) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:139 @ static inline void activate_mm(struct mm unsigned long flags; int cpu; - spin_lock_irqsave(&mm->context.lock, flags); + raw_spin_lock_irqsave(&mm->context.lock, flags); if (!CTX_VALID(mm->context)) get_new_mmu_context(mm); cpu = smp_processor_id(); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:149 @ static inline void activate_mm(struct mm load_secondary_context(mm); __flush_tlb_mm(CTX_HWBITS(mm->context), SECONDARY_CONTEXT); tsb_context_switch(mm); - spin_unlock_irqrestore(&mm->context.lock, flags); + raw_spin_unlock_irqrestore(&mm->context.lock, flags); } #endif /* !(__ASSEMBLY__) */ Index: linux-3.12.19-rt30/arch/sparc/kernel/irq_64.c =================================================================== --- linux-3.12.19-rt30.orig/arch/sparc/kernel/irq_64.c +++ linux-3.12.19-rt30/arch/sparc/kernel/irq_64.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:701 @ void __irq_entry handler_irq(int pil, st set_irq_regs(old_regs); } +#ifndef CONFIG_PREEMPT_RT_FULL void do_softirq(void) { unsigned long flags; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:727 @ void do_softirq(void) local_irq_restore(flags); } +#endif #ifdef CONFIG_HOTPLUG_CPU void fixup_irqs(void) Index: linux-3.12.19-rt30/arch/sparc/kernel/pcr.c =================================================================== --- linux-3.12.19-rt30.orig/arch/sparc/kernel/pcr.c +++ linux-3.12.19-rt30/arch/sparc/kernel/pcr.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:46 @ void __irq_entry deferred_pcr_work_irq(i set_irq_regs(old_regs); } +#ifndef CONFIG_PREEMPT_RT_FULL void arch_irq_work_raise(void) { set_softint(1 << PIL_DEFERRED_PCR_WORK); } +#endif const struct pcr_ops *pcr_ops; EXPORT_SYMBOL_GPL(pcr_ops); Index: linux-3.12.19-rt30/arch/sparc/kernel/setup_32.c =================================================================== --- linux-3.12.19-rt30.orig/arch/sparc/kernel/setup_32.c +++ linux-3.12.19-rt30/arch/sparc/kernel/setup_32.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:312 @ void __init setup_arch(char **cmdline_p) boot_flags_init(*cmdline_p); + early_console = &prom_early_console; register_console(&prom_early_console); printk("ARCH: "); Index: linux-3.12.19-rt30/arch/sparc/kernel/setup_64.c =================================================================== --- linux-3.12.19-rt30.orig/arch/sparc/kernel/setup_64.c +++ linux-3.12.19-rt30/arch/sparc/kernel/setup_64.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:558 @ static void __init init_sparc64_elf_hwca pause_patch(); } +static inline void register_prom_console(void) +{ + early_console = &prom_early_console; + register_console(&prom_early_console); +} + void __init setup_arch(char **cmdline_p) { /* Initialize PROM console and command line. */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:575 @ void __init setup_arch(char **cmdline_p) #ifdef CONFIG_EARLYFB if (btext_find_display()) #endif - register_console(&prom_early_console); + register_prom_console(); if (tlb_type == hypervisor) printk("ARCH: SUN4V\n"); Index: linux-3.12.19-rt30/arch/sparc/kernel/smp_64.c =================================================================== --- linux-3.12.19-rt30.orig/arch/sparc/kernel/smp_64.c +++ linux-3.12.19-rt30/arch/sparc/kernel/smp_64.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:979 @ void __irq_entry smp_new_mmu_context_ver if (unlikely(!mm || (mm == &init_mm))) return; - spin_lock_irqsave(&mm->context.lock, flags); + raw_spin_lock_irqsave(&mm->context.lock, flags); if (unlikely(!CTX_VALID(mm->context))) get_new_mmu_context(mm); - spin_unlock_irqrestore(&mm->context.lock, flags); + raw_spin_unlock_irqrestore(&mm->context.lock, flags); load_secondary_context(mm); __flush_tlb_mm(CTX_HWBITS(mm->context), Index: linux-3.12.19-rt30/arch/sparc/mm/fault_32.c =================================================================== --- linux-3.12.19-rt30.orig/arch/sparc/mm/fault_32.c +++ linux-3.12.19-rt30/arch/sparc/mm/fault_32.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:202 @ asmlinkage void do_sparc_fault(struct pt * If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm) + if (!mm || pagefault_disabled()) goto no_context; perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address); Index: linux-3.12.19-rt30/arch/sparc/mm/fault_64.c =================================================================== --- linux-3.12.19-rt30.orig/arch/sparc/mm/fault_64.c +++ linux-3.12.19-rt30/arch/sparc/mm/fault_64.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:333 @ asmlinkage void __kprobes do_sparc64_fau * If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm) + if (!mm || pagefault_disabled()) goto intr_or_no_mm; perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address); Index: linux-3.12.19-rt30/arch/sparc/mm/init_64.c =================================================================== --- linux-3.12.19-rt30.orig/arch/sparc/mm/init_64.c +++ linux-3.12.19-rt30/arch/sparc/mm/init_64.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:357 @ void update_mmu_cache(struct vm_area_str if (!pte_accessible(mm, pte)) return; - spin_lock_irqsave(&mm->context.lock, flags); + raw_spin_lock_irqsave(&mm->context.lock, flags); #if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE) if (mm->context.huge_pte_count && is_hugetlb_pte(pte)) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:368 @ void update_mmu_cache(struct vm_area_str __update_mmu_tsb_insert(mm, MM_TSB_BASE, PAGE_SHIFT, address, pte_val(pte)); - spin_unlock_irqrestore(&mm->context.lock, flags); + raw_spin_unlock_irqrestore(&mm->context.lock, flags); } void flush_dcache_page(struct page *page) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:668 @ void __flush_dcache_range(unsigned long EXPORT_SYMBOL(__flush_dcache_range); /* get_new_mmu_context() uses "cache + 1". */ -DEFINE_SPINLOCK(ctx_alloc_lock); +DEFINE_RAW_SPINLOCK(ctx_alloc_lock); unsigned long tlb_context_cache = CTX_FIRST_VERSION - 1; #define MAX_CTX_NR (1UL << CTX_NR_BITS) #define CTX_BMAP_SLOTS BITS_TO_LONGS(MAX_CTX_NR) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:690 @ void get_new_mmu_context(struct mm_struc unsigned long orig_pgsz_bits; int new_version; - spin_lock(&ctx_alloc_lock); + raw_spin_lock(&ctx_alloc_lock); orig_pgsz_bits = (mm->context.sparc64_ctx_val & CTX_PGSZ_MASK); ctx = (tlb_context_cache + 1) & CTX_NR_MASK; new_ctx = find_next_zero_bit(mmu_context_bmap, 1 << CTX_NR_BITS, ctx); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:726 @ void get_new_mmu_context(struct mm_struc out: tlb_context_cache = new_ctx; mm->context.sparc64_ctx_val = new_ctx | orig_pgsz_bits; - spin_unlock(&ctx_alloc_lock); + raw_spin_unlock(&ctx_alloc_lock); if (unlikely(new_version)) smp_new_mmu_context_version(); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2728 @ void hugetlb_setup(struct pt_regs *regs) if (tlb_type == cheetah_plus) { unsigned long ctx; - spin_lock(&ctx_alloc_lock); + raw_spin_lock(&ctx_alloc_lock); ctx = mm->context.sparc64_ctx_val; ctx &= ~CTX_PGSZ_MASK; ctx |= CTX_PGSZ_BASE << CTX_PGSZ0_SHIFT; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2749 @ void hugetlb_setup(struct pt_regs *regs) mm->context.sparc64_ctx_val = ctx; on_each_cpu(context_reload, mm, 0); } - spin_unlock(&ctx_alloc_lock); + raw_spin_unlock(&ctx_alloc_lock); } } #endif Index: linux-3.12.19-rt30/arch/sparc/mm/tsb.c =================================================================== --- linux-3.12.19-rt30.orig/arch/sparc/mm/tsb.c +++ linux-3.12.19-rt30/arch/sparc/mm/tsb.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:76 @ void flush_tsb_user(struct tlb_batch *tb struct mm_struct *mm = tb->mm; unsigned long nentries, base, flags; - spin_lock_irqsave(&mm->context.lock, flags); + raw_spin_lock_irqsave(&mm->context.lock, flags); base = (unsigned long) mm->context.tsb_block[MM_TSB_BASE].tsb; nentries = mm->context.tsb_block[MM_TSB_BASE].tsb_nentries; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:93 @ void flush_tsb_user(struct tlb_batch *tb __flush_tsb_one(tb, HPAGE_SHIFT, base, nentries); } #endif - spin_unlock_irqrestore(&mm->context.lock, flags); + raw_spin_unlock_irqrestore(&mm->context.lock, flags); } void flush_tsb_user_page(struct mm_struct *mm, unsigned long vaddr) { unsigned long nentries, base, flags; - spin_lock_irqsave(&mm->context.lock, flags); + raw_spin_lock_irqsave(&mm->context.lock, flags); base = (unsigned long) mm->context.tsb_block[MM_TSB_BASE].tsb; nentries = mm->context.tsb_block[MM_TSB_BASE].tsb_nentries; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:117 @ void flush_tsb_user_page(struct mm_struc __flush_tsb_one_entry(base, vaddr, HPAGE_SHIFT, nentries); } #endif - spin_unlock_irqrestore(&mm->context.lock, flags); + raw_spin_unlock_irqrestore(&mm->context.lock, flags); } #define HV_PGSZ_IDX_BASE HV_PGSZ_IDX_8K @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:407 @ retry_tsb_alloc: * the lock and ask all other cpus running this address space * to run tsb_context_switch() to see the new TSB table. */ - spin_lock_irqsave(&mm->context.lock, flags); + raw_spin_lock_irqsave(&mm->context.lock, flags); old_tsb = mm->context.tsb_block[tsb_index].tsb; old_cache_index = @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:422 @ retry_tsb_alloc: */ if (unlikely(old_tsb && (rss < mm->context.tsb_block[tsb_index].tsb_rss_limit))) { - spin_unlock_irqrestore(&mm->context.lock, flags); + raw_spin_unlock_irqrestore(&mm->context.lock, flags); kmem_cache_free(tsb_caches[new_cache_index], new_tsb); return; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:448 @ retry_tsb_alloc: mm->context.tsb_block[tsb_index].tsb = new_tsb; setup_tsb_params(mm, tsb_index, new_size); - spin_unlock_irqrestore(&mm->context.lock, flags); + raw_spin_unlock_irqrestore(&mm->context.lock, flags); /* If old_tsb is NULL, we're being invoked for the first time * from init_new_context(). @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:474 @ int init_new_context(struct task_struct #endif unsigned int i; - spin_lock_init(&mm->context.lock); + raw_spin_lock_init(&mm->context.lock); mm->context.sparc64_ctx_val = 0UL; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:538 @ void destroy_context(struct mm_struct *m free_hot_cold_page(page, 0); } - spin_lock_irqsave(&ctx_alloc_lock, flags); + raw_spin_lock_irqsave(&ctx_alloc_lock, flags); if (CTX_VALID(mm->context)) { unsigned long nr = CTX_NRBITS(mm->context); mmu_context_bmap[nr>>6] &= ~(1UL << (nr & 63)); } - spin_unlock_irqrestore(&ctx_alloc_lock, flags); + raw_spin_unlock_irqrestore(&ctx_alloc_lock, flags); } Index: linux-3.12.19-rt30/arch/tile/mm/fault.c =================================================================== --- linux-3.12.19-rt30.orig/arch/tile/mm/fault.c +++ linux-3.12.19-rt30/arch/tile/mm/fault.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:360 @ static int handle_page_fault(struct pt_r * If we're in an interrupt, have no user context or are running in an * atomic region then we must not take the fault. */ - if (in_atomic() || !mm) { + if (!mm || pagefault_disabled()) { vma = NULL; /* happy compiler */ goto bad_area_nosemaphore; } Index: linux-3.12.19-rt30/arch/um/kernel/trap.c =================================================================== --- linux-3.12.19-rt30.orig/arch/um/kernel/trap.c +++ linux-3.12.19-rt30/arch/um/kernel/trap.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:41 @ int handle_page_fault(unsigned long addr * If the fault was during atomic operation, don't take the fault, just * fail. */ - if (in_atomic()) + if (pagefault_disabled()) goto out_nosemaphore; if (is_user) Index: linux-3.12.19-rt30/arch/x86/Kconfig =================================================================== --- linux-3.12.19-rt30.orig/arch/x86/Kconfig +++ linux-3.12.19-rt30/arch/x86/Kconfig @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:24 @ config X86_64 ### Arch settings config X86 def_bool y + select HAVE_PREEMPT_LAZY select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS select HAVE_AOUT if X86_32 select HAVE_UNSTABLE_SCHED_CLOCK @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:184 @ config ARCH_MAY_HAVE_PC_FDC def_bool y depends on ISA_DMA_API +config RWSEM_GENERIC_SPINLOCK + def_bool PREEMPT_RT_FULL + config RWSEM_XCHGADD_ALGORITHM - def_bool y + def_bool !RWSEM_GENERIC_SPINLOCK && !PREEMPT_RT_FULL config GENERIC_CALIBRATE_DELAY def_bool y @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:478 @ config X86_MDFLD select MFD_INTEL_MSIC ---help--- Medfield is Intel's Low Power Intel Architecture (LPIA) based Moblin - Internet Device(MID) platform. + Internet Device(MID) platform. Unlike standard x86 PCs, Medfield does not have many legacy devices nor standard legacy replacement devices/features. e.g. Medfield does not contain i8259, i8254, HPET, legacy BIOS, most of the io ports. @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:825 @ config IOMMU_HELPER config MAXSMP bool "Enable Maximum number of SMP Processors and NUMA Nodes" depends on X86_64 && SMP && DEBUG_KERNEL - select CPUMASK_OFFSTACK + select CPUMASK_OFFSTACK if !PREEMPT_RT_FULL ---help--- Enable maximum number of CPUS and NUMA Nodes for this architecture. If unsure, say N. Index: linux-3.12.19-rt30/arch/x86/crypto/aesni-intel_glue.c =================================================================== --- linux-3.12.19-rt30.orig/arch/x86/crypto/aesni-intel_glue.c +++ linux-3.12.19-rt30/arch/x86/crypto/aesni-intel_glue.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:255 @ static int ecb_encrypt(struct blkcipher_ err = blkcipher_walk_virt(desc, &walk); desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP; - 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); + nbytes & AES_BLOCK_MASK); + kernel_fpu_end(); nbytes &= AES_BLOCK_SIZE - 1; err = blkcipher_walk_done(desc, &walk, nbytes); } - kernel_fpu_end(); return err; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:279 @ static int ecb_decrypt(struct blkcipher_ err = blkcipher_walk_virt(desc, &walk); desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP; - 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 = blkcipher_walk_done(desc, &walk, nbytes); } - kernel_fpu_end(); return err; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:303 @ static int cbc_encrypt(struct blkcipher_ err = blkcipher_walk_virt(desc, &walk); desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP; - 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 = blkcipher_walk_done(desc, &walk, nbytes); } - kernel_fpu_end(); return err; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:327 @ static int cbc_decrypt(struct blkcipher_ err = blkcipher_walk_virt(desc, &walk); desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP; - 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 = blkcipher_walk_done(desc, &walk, nbytes); } - kernel_fpu_end(); return err; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:367 @ static int ctr_crypt(struct blkcipher_de err = blkcipher_walk_virt_block(desc, &walk, AES_BLOCK_SIZE); desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP; - kernel_fpu_begin(); while ((nbytes = walk.nbytes) >= AES_BLOCK_SIZE) { + kernel_fpu_begin(); aesni_ctr_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 = blkcipher_walk_done(desc, &walk, nbytes); } if (walk.nbytes) { + kernel_fpu_begin(); ctr_crypt_final(ctx, &walk); + kernel_fpu_end(); err = blkcipher_walk_done(desc, &walk, 0); } - kernel_fpu_end(); return err; } Index: linux-3.12.19-rt30/arch/x86/crypto/cast5_avx_glue.c =================================================================== --- linux-3.12.19-rt30.orig/arch/x86/crypto/cast5_avx_glue.c +++ linux-3.12.19-rt30/arch/x86/crypto/cast5_avx_glue.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:63 @ static inline void cast5_fpu_end(bool fp static int ecb_crypt(struct blkcipher_desc *desc, struct blkcipher_walk *walk, bool enc) { - bool fpu_enabled = false; + bool fpu_enabled; struct cast5_ctx *ctx = crypto_blkcipher_ctx(desc->tfm); const unsigned int bsize = CAST5_BLOCK_SIZE; unsigned int nbytes; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:79 @ static int ecb_crypt(struct blkcipher_de u8 *wsrc = walk->src.virt.addr; u8 *wdst = walk->dst.virt.addr; - fpu_enabled = cast5_fpu_begin(fpu_enabled, nbytes); + fpu_enabled = cast5_fpu_begin(false, nbytes); /* Process multi-block batch */ if (nbytes >= bsize * CAST5_PARALLEL_BLOCKS) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:107 @ static int ecb_crypt(struct blkcipher_de } while (nbytes >= bsize); done: + cast5_fpu_end(fpu_enabled); err = blkcipher_walk_done(desc, walk, nbytes); } - - cast5_fpu_end(fpu_enabled); return err; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:233 @ done: static int cbc_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { - bool fpu_enabled = false; + bool fpu_enabled; struct blkcipher_walk walk; int err; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:242 @ static int cbc_decrypt(struct blkcipher_ desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP; while ((nbytes = walk.nbytes)) { - fpu_enabled = cast5_fpu_begin(fpu_enabled, nbytes); + fpu_enabled = cast5_fpu_begin(false, nbytes); nbytes = __cbc_decrypt(desc, &walk); + cast5_fpu_end(fpu_enabled); err = blkcipher_walk_done(desc, &walk, nbytes); } - - cast5_fpu_end(fpu_enabled); return err; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:316 @ done: static int ctr_crypt(struct blkcipher_desc *desc, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { - bool fpu_enabled = false; + bool fpu_enabled; struct blkcipher_walk walk; int err; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:325 @ static int ctr_crypt(struct blkcipher_de desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP; while ((nbytes = walk.nbytes) >= CAST5_BLOCK_SIZE) { - fpu_enabled = cast5_fpu_begin(fpu_enabled, nbytes); + fpu_enabled = cast5_fpu_begin(false, nbytes); nbytes = __ctr_crypt(desc, &walk); + cast5_fpu_end(fpu_enabled); err = blkcipher_walk_done(desc, &walk, nbytes); } - cast5_fpu_end(fpu_enabled); - if (walk.nbytes) { ctr_crypt_final(desc, &walk); err = blkcipher_walk_done(desc, &walk, 0); Index: linux-3.12.19-rt30/arch/x86/crypto/glue_helper.c =================================================================== --- linux-3.12.19-rt30.orig/arch/x86/crypto/glue_helper.c +++ linux-3.12.19-rt30/arch/x86/crypto/glue_helper.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:42 @ static int __glue_ecb_crypt_128bit(const void *ctx = crypto_blkcipher_ctx(desc->tfm); const unsigned int bsize = 128 / 8; unsigned int nbytes, i, func_bytes; - bool fpu_enabled = false; + bool fpu_enabled; int err; err = blkcipher_walk_virt(desc, walk); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:52 @ static int __glue_ecb_crypt_128bit(const u8 *wdst = walk->dst.virt.addr; fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit, - desc, fpu_enabled, nbytes); + desc, false, nbytes); for (i = 0; i < gctx->num_funcs; i++) { func_bytes = bsize * gctx->funcs[i].num_blocks; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:74 @ static int __glue_ecb_crypt_128bit(const } done: + glue_fpu_end(fpu_enabled); err = blkcipher_walk_done(desc, walk, nbytes); } - glue_fpu_end(fpu_enabled); return err; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:197 @ int glue_cbc_decrypt_128bit(const struct struct scatterlist *src, unsigned int nbytes) { const unsigned int bsize = 128 / 8; - bool fpu_enabled = false; + bool fpu_enabled; struct blkcipher_walk walk; int err; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:206 @ int glue_cbc_decrypt_128bit(const struct while ((nbytes = walk.nbytes)) { fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit, - desc, fpu_enabled, nbytes); + desc, false, nbytes); nbytes = __glue_cbc_decrypt_128bit(gctx, desc, &walk); + glue_fpu_end(fpu_enabled); err = blkcipher_walk_done(desc, &walk, nbytes); } - glue_fpu_end(fpu_enabled); return err; } EXPORT_SYMBOL_GPL(glue_cbc_decrypt_128bit); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:281 @ int glue_ctr_crypt_128bit(const struct c struct scatterlist *src, unsigned int nbytes) { const unsigned int bsize = 128 / 8; - bool fpu_enabled = false; + bool fpu_enabled; struct blkcipher_walk walk; int err; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:290 @ int glue_ctr_crypt_128bit(const struct c while ((nbytes = walk.nbytes) >= bsize) { fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit, - desc, fpu_enabled, nbytes); + desc, false, nbytes); nbytes = __glue_ctr_crypt_128bit(gctx, desc, &walk); + glue_fpu_end(fpu_enabled); err = blkcipher_walk_done(desc, &walk, nbytes); } - glue_fpu_end(fpu_enabled); - if (walk.nbytes) { glue_ctr_crypt_final_128bit( gctx->funcs[gctx->num_funcs - 1].fn_u.ctr, desc, &walk); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:350 @ int glue_xts_crypt_128bit(const struct c void *tweak_ctx, void *crypt_ctx) { const unsigned int bsize = 128 / 8; - bool fpu_enabled = false; + bool fpu_enabled; struct blkcipher_walk walk; int err; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:363 @ int glue_xts_crypt_128bit(const struct c /* set minimum length to bsize, for tweak_fn */ fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit, - desc, fpu_enabled, + desc, false, nbytes < bsize ? bsize : nbytes); - /* calculate first value of T */ tweak_fn(tweak_ctx, walk.iv, walk.iv); + glue_fpu_end(fpu_enabled); while (nbytes) { + fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit, + desc, false, nbytes); nbytes = __glue_xts_crypt_128bit(gctx, crypt_ctx, desc, &walk); + glue_fpu_end(fpu_enabled); err = blkcipher_walk_done(desc, &walk, nbytes); nbytes = walk.nbytes; } - - glue_fpu_end(fpu_enabled); - return err; } EXPORT_SYMBOL_GPL(glue_xts_crypt_128bit); Index: linux-3.12.19-rt30/arch/x86/include/asm/signal.h =================================================================== --- linux-3.12.19-rt30.orig/arch/x86/include/asm/signal.h +++ linux-3.12.19-rt30/arch/x86/include/asm/signal.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:26 @ typedef struct { unsigned long sig[_NSIG_WORDS]; } sigset_t; +/* + * 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_FULL 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_FULL) && defined(CONFIG_X86_64) +#define ARCH_RT_DELAYS_SIGNAL_SEND +#endif + #ifndef CONFIG_COMPAT typedef sigset_t compat_sigset_t; #endif Index: linux-3.12.19-rt30/arch/x86/include/asm/stackprotector.h =================================================================== --- linux-3.12.19-rt30.orig/arch/x86/include/asm/stackprotector.h +++ linux-3.12.19-rt30/arch/x86/include/asm/stackprotector.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:60 @ */ static __always_inline void boot_init_stack_canary(void) { - u64 canary; + u64 uninitialized_var(canary); u64 tsc; #ifdef CONFIG_X86_64 @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:71 @ static __always_inline void boot_init_st * 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_FULL get_random_bytes(&canary, sizeof(canary)); +#endif tsc = __native_read_tsc(); canary += tsc + (tsc << 32UL); Index: linux-3.12.19-rt30/arch/x86/include/asm/thread_info.h =================================================================== --- linux-3.12.19-rt30.orig/arch/x86/include/asm/thread_info.h +++ linux-3.12.19-rt30/arch/x86/include/asm/thread_info.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:33 @ struct thread_info { __u32 cpu; /* current CPU */ int preempt_count; /* 0 => preemptable, <0 => BUG */ + int preempt_lazy_count; /* 0 => lazy preemptable, + <0 => BUG */ mm_segment_t addr_limit; struct restart_block restart_block; void __user *sysenter_return; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:86 @ struct thread_info { #define TIF_SYSCALL_EMU 6 /* syscall emulation active */ #define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */ #define TIF_SECCOMP 8 /* secure computing */ +#define TIF_NEED_RESCHED_LAZY 9 /* lazy rescheduling necessary */ #define TIF_MCE_NOTIFY 10 /* notify userspace of an MCE */ #define TIF_USER_RETURN_NOTIFY 11 /* notify kernel of userspace return */ #define TIF_UPROBE 12 /* breakpointed or singlestepping */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:111 @ struct thread_info { #define _TIF_SYSCALL_EMU (1 << TIF_SYSCALL_EMU) #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) #define _TIF_SECCOMP (1 << TIF_SECCOMP) +#define _TIF_NEED_RESCHED_LAZY (1 << TIF_NEED_RESCHED_LAZY) #define _TIF_MCE_NOTIFY (1 << TIF_MCE_NOTIFY) #define _TIF_USER_RETURN_NOTIFY (1 << TIF_USER_RETURN_NOTIFY) #define _TIF_UPROBE (1 << TIF_UPROBE) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:161 @ struct thread_info { #define _TIF_WORK_CTXSW_PREV (_TIF_WORK_CTXSW|_TIF_USER_RETURN_NOTIFY) #define _TIF_WORK_CTXSW_NEXT (_TIF_WORK_CTXSW) +#define _TIF_NEED_RESCHED_MASK (_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY) + #define PREEMPT_ACTIVE 0x10000000 #ifdef CONFIG_X86_32 Index: linux-3.12.19-rt30/arch/x86/kernel/apic/io_apic.c =================================================================== --- linux-3.12.19-rt30.orig/arch/x86/kernel/apic/io_apic.c +++ linux-3.12.19-rt30/arch/x86/kernel/apic/io_apic.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2399 @ static bool io_apic_level_ack_pending(st static inline bool ioapic_irqd_mask(struct irq_data *data, struct irq_cfg *cfg) { /* If we are moving the irq we need to mask it */ - if (unlikely(irqd_is_setaffinity_pending(data))) { + if (unlikely(irqd_is_setaffinity_pending(data) && + !irqd_irq_inprogress(data))) { mask_ioapic(cfg); return true; } Index: linux-3.12.19-rt30/arch/x86/kernel/asm-offsets.c =================================================================== --- linux-3.12.19-rt30.orig/arch/x86/kernel/asm-offsets.c +++ linux-3.12.19-rt30/arch/x86/kernel/asm-offsets.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:36 @ void common(void) { OFFSET(TI_status, thread_info, status); OFFSET(TI_addr_limit, thread_info, addr_limit); OFFSET(TI_preempt_count, thread_info, preempt_count); + OFFSET(TI_preempt_lazy_count, thread_info, preempt_lazy_count); BLANK(); OFFSET(crypto_tfm_ctx_offset, crypto_tfm, __crt_ctx); Index: linux-3.12.19-rt30/arch/x86/kernel/cpu/mcheck/mce.c =================================================================== --- linux-3.12.19-rt30.orig/arch/x86/kernel/cpu/mcheck/mce.c +++ linux-3.12.19-rt30/arch/x86/kernel/cpu/mcheck/mce.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:21 @ #include <linux/rcupdate.h> #include <linux/kobject.h> #include <linux/uaccess.h> +#include <linux/kthread.h> #include <linux/kdebug.h> #include <linux/kernel.h> #include <linux/percpu.h> @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:45 @ #include <linux/debugfs.h> #include <linux/irq_work.h> #include <linux/export.h> +#include <linux/jiffies.h> #include <asm/processor.h> #include <asm/mce.h> @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1273 @ void mce_log_therm_throt_event(__u64 sta static unsigned long check_interval = 5 * 60; /* 5 minutes */ static DEFINE_PER_CPU(unsigned long, mce_next_interval); /* in jiffies */ -static DEFINE_PER_CPU(struct timer_list, mce_timer); +static DEFINE_PER_CPU(struct hrtimer, mce_timer); static unsigned long mce_adjust_timer_default(unsigned long interval) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1283 @ static unsigned long mce_adjust_timer_de static unsigned long (*mce_adjust_timer)(unsigned long interval) = mce_adjust_timer_default; -static void mce_timer_fn(unsigned long data) +static enum hrtimer_restart mce_timer_fn(struct hrtimer *timer) { - struct timer_list *t = &__get_cpu_var(mce_timer); unsigned long iv; - WARN_ON(smp_processor_id() != data); - if (mce_available(__this_cpu_ptr(&cpu_info))) { machine_check_poll(MCP_TIMESTAMP, &__get_cpu_var(mce_poll_banks)); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1307 @ static void mce_timer_fn(unsigned long d __this_cpu_write(mce_next_interval, iv); /* Might have become 0 after CMCI storm subsided */ if (iv) { - t->expires = jiffies + iv; - add_timer_on(t, smp_processor_id()); + hrtimer_forward_now(timer, ns_to_ktime( + jiffies_to_usecs(iv) * 1000ULL)); + return HRTIMER_RESTART; } + return HRTIMER_NORESTART; } /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1319 @ static void mce_timer_fn(unsigned long d */ void mce_timer_kick(unsigned long interval) { - struct timer_list *t = &__get_cpu_var(mce_timer); - unsigned long when = jiffies + interval; + struct hrtimer *t = &__get_cpu_var(mce_timer); unsigned long iv = __this_cpu_read(mce_next_interval); - if (timer_pending(t)) { - if (time_before(when, t->expires)) - mod_timer_pinned(t, when); + if (hrtimer_active(t)) { + s64 exp; + s64 intv_us; + + intv_us = jiffies_to_usecs(interval); + exp = ktime_to_us(hrtimer_expires_remaining(t)); + if (intv_us < exp) { + hrtimer_cancel(t); + hrtimer_start_range_ns(t, + ns_to_ktime(intv_us * 1000), + 0, HRTIMER_MODE_REL_PINNED); + } } else { - t->expires = round_jiffies(when); - add_timer_on(t, smp_processor_id()); + hrtimer_start_range_ns(t, + ns_to_ktime(jiffies_to_usecs(interval) * 1000ULL), + 0, HRTIMER_MODE_REL_PINNED); } if (interval < iv) __this_cpu_write(mce_next_interval, interval); } -/* Must not be called in IRQ context where del_timer_sync() can deadlock */ +/* Must not be called in IRQ context where hrtimer_cancel() can deadlock */ static void mce_timer_delete_all(void) { int cpu; for_each_online_cpu(cpu) - del_timer_sync(&per_cpu(mce_timer, cpu)); + hrtimer_cancel(&per_cpu(mce_timer, cpu)); } static void mce_do_trigger(struct work_struct *work) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1359 @ static void mce_do_trigger(struct work_s static DECLARE_WORK(mce_trigger_work, mce_do_trigger); +static void __mce_notify_work(void) +{ + /* Not more than two messages every minute */ + static DEFINE_RATELIMIT_STATE(ratelimit, 60*HZ, 2); + + /* wake processes polling /dev/mcelog */ + wake_up_interruptible(&mce_chrdev_wait); + + /* + * There is no risk of missing notifications because + * work_pending is always cleared before the function is + * executed. + */ + if (mce_helper[0] && !work_pending(&mce_trigger_work)) + schedule_work(&mce_trigger_work); + + if (__ratelimit(&ratelimit)) + pr_info(HW_ERR "Machine check events logged\n"); +} + +#ifdef CONFIG_PREEMPT_RT_FULL +struct task_struct *mce_notify_helper; + +static int mce_notify_helper_thread(void *unused) +{ + while (1) { + set_current_state(TASK_INTERRUPTIBLE); + schedule(); + if (kthread_should_stop()) + break; + __mce_notify_work(); + } + return 0; +} + +static int mce_notify_work_init(void) +{ + mce_notify_helper = kthread_run(mce_notify_helper_thread, NULL, + "mce-notify"); + if (!mce_notify_helper) + return -ENOMEM; + + return 0; +} + +static void mce_notify_work(void) +{ + wake_up_process(mce_notify_helper); +} +#else +static void mce_notify_work(void) +{ + __mce_notify_work(); +} +static inline int mce_notify_work_init(void) { return 0; } +#endif + /* * Notify the user(s) about new machine check events. * Can be called from interrupt context, but not from machine check/NMI @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1423 @ static DECLARE_WORK(mce_trigger_work, mc */ int mce_notify_irq(void) { - /* Not more than two messages every minute */ - static DEFINE_RATELIMIT_STATE(ratelimit, 60*HZ, 2); - if (test_and_clear_bit(0, &mce_need_notify)) { - /* wake processes polling /dev/mcelog */ - wake_up_interruptible(&mce_chrdev_wait); - - if (mce_helper[0]) - schedule_work(&mce_trigger_work); - - if (__ratelimit(&ratelimit)) - pr_info(HW_ERR "Machine check events logged\n"); - + mce_notify_work(); return 1; } return 0; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1695 @ static void __mcheck_cpu_init_vendor(str } } -static void mce_start_timer(unsigned int cpu, struct timer_list *t) +static void mce_start_timer(unsigned int cpu, struct hrtimer *t) { unsigned long iv = mce_adjust_timer(check_interval * HZ); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1704 @ static void mce_start_timer(unsigned int if (mca_cfg.ignore_ce || !iv) return; - t->expires = round_jiffies(jiffies + iv); - add_timer_on(t, smp_processor_id()); + hrtimer_start_range_ns(t, ns_to_ktime(jiffies_to_usecs(iv) * 1000ULL), + 0, HRTIMER_MODE_REL_PINNED); } static void __mcheck_cpu_init_timer(void) { - struct timer_list *t = &__get_cpu_var(mce_timer); + struct hrtimer *t = &__get_cpu_var(mce_timer); unsigned int cpu = smp_processor_id(); - setup_timer(t, mce_timer_fn, cpu); + hrtimer_init(t, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + t->function = mce_timer_fn; mce_start_timer(cpu, t); } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2389 @ static void mce_disable_cpu(void *h) if (!mce_available(__this_cpu_ptr(&cpu_info))) return; + hrtimer_cancel(&__get_cpu_var(mce_timer)); + if (!(action & CPU_TASKS_FROZEN)) cmci_clear(); for (i = 0; i < mca_cfg.banks; i++) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2417 @ static void mce_reenable_cpu(void *h) if (b->init) wrmsrl(MSR_IA32_MCx_CTL(i), b->ctl); } + __mcheck_cpu_init_timer(); } /* Get notified when a cpu comes on/off. Be hotplug friendly. */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2425 @ static int mce_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu) { unsigned int cpu = (unsigned long)hcpu; - struct timer_list *t = &per_cpu(mce_timer, cpu); switch (action & ~CPU_TASKS_FROZEN) { case CPU_ONLINE: @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2440 @ mce_cpu_callback(struct notifier_block * break; case CPU_DOWN_PREPARE: smp_call_function_single(cpu, mce_disable_cpu, &action, 1); - del_timer_sync(t); break; case CPU_DOWN_FAILED: smp_call_function_single(cpu, mce_reenable_cpu, &action, 1); - mce_start_timer(cpu, t); break; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2504 @ static __init int mcheck_init_device(voi /* register character device /dev/mcelog */ misc_register(&mce_chrdev_device); + err = mce_notify_work_init(); + return err; } device_initcall_sync(mcheck_init_device); Index: linux-3.12.19-rt30/arch/x86/kernel/entry_32.S =================================================================== --- linux-3.12.19-rt30.orig/arch/x86/kernel/entry_32.S +++ linux-3.12.19-rt30/arch/x86/kernel/entry_32.S @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:367 @ ENTRY(resume_kernel) DISABLE_INTERRUPTS(CLBR_ANY) cmpl $0,TI_preempt_count(%ebp) # non-zero preempt_count ? jnz restore_all -need_resched: movl TI_flags(%ebp), %ecx # need_resched set ? testb $_TIF_NEED_RESCHED, %cl + jnz 1f + + cmpl $0,TI_preempt_lazy_count(%ebp) # non-zero preempt_lazy_count ? + jnz restore_all + testl $_TIF_NEED_RESCHED_LAZY, %ecx jz restore_all - testl $X86_EFLAGS_IF,PT_EFLAGS(%esp) # interrupts off (exception path) ? + +1: testl $X86_EFLAGS_IF,PT_EFLAGS(%esp) # interrupts off (exception path) ? jz restore_all call preempt_schedule_irq - jmp need_resched + movl TI_flags(%ebp), %ecx # need_resched set ? + testl $_TIF_NEED_RESCHED_MASK, %ecx + jnz 1b + jmp restore_all END(resume_kernel) #endif CFI_ENDPROC @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:619 @ ENDPROC(system_call) ALIGN RING0_PTREGS_FRAME # can't unwind into user space anyway work_pending: - testb $_TIF_NEED_RESCHED, %cl + testl $_TIF_NEED_RESCHED_MASK, %ecx jz work_notifysig work_resched: call schedule @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:632 @ work_resched: andl $_TIF_WORK_MASK, %ecx # is there any work to be done other # than syscall tracing? jz restore_all - testb $_TIF_NEED_RESCHED, %cl + testl $_TIF_NEED_RESCHED_MASK, %ecx jnz work_resched work_notifysig: # deal with pending signals and Index: linux-3.12.19-rt30/arch/x86/kernel/entry_64.S =================================================================== --- linux-3.12.19-rt30.orig/arch/x86/kernel/entry_64.S +++ linux-3.12.19-rt30/arch/x86/kernel/entry_64.S @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:662 @ sysret_check: /* Handle reschedules */ /* edx: work, edi: workmask */ sysret_careful: - bt $TIF_NEED_RESCHED,%edx - jnc sysret_signal + testl $_TIF_NEED_RESCHED_MASK,%edx + jz sysret_signal TRACE_IRQS_ON ENABLE_INTERRUPTS(CLBR_NONE) pushq_cfi %rdi @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:775 @ GLOBAL(int_with_check) /* First do a reschedule test. */ /* edx: work, edi: workmask */ int_careful: - bt $TIF_NEED_RESCHED,%edx - jnc int_very_careful + testl $_TIF_NEED_RESCHED_MASK,%edx + jz int_very_careful TRACE_IRQS_ON ENABLE_INTERRUPTS(CLBR_NONE) pushq_cfi %rdi @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1108 @ bad_iret: /* edi: workmask, edx: work */ retint_careful: CFI_RESTORE_STATE - bt $TIF_NEED_RESCHED,%edx - jnc retint_signal + testl $_TIF_NEED_RESCHED_MASK,%edx + jz retint_signal TRACE_IRQS_ON ENABLE_INTERRUPTS(CLBR_NONE) pushq_cfi %rdi @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1142 @ retint_signal: ENTRY(retint_kernel) cmpl $0,TI_preempt_count(%rcx) jnz retint_restore_args - bt $TIF_NEED_RESCHED,TI_flags(%rcx) + bt $TIF_NEED_RESCHED,TI_flags(%rcx) + jc 1f + + cmpl $0,TI_preempt_lazy_count(%rcx) + jnz retint_restore_args + bt $TIF_NEED_RESCHED_LAZY,TI_flags(%rcx) jnc retint_restore_args - bt $9,EFLAGS-ARGOFFSET(%rsp) /* interrupts off? */ + +1: bt $9,EFLAGS-ARGOFFSET(%rsp) /* interrupts off? */ jnc retint_restore_args call preempt_schedule_irq jmp exit_intr @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1415 @ bad_gs: jmp 2b .previous +#ifndef CONFIG_PREEMPT_RT_FULL /* Call softirq on interrupt stack. Interrupts are off. */ ENTRY(call_softirq) CFI_STARTPROC @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1435 @ ENTRY(call_softirq) ret CFI_ENDPROC END(call_softirq) +#endif #ifdef CONFIG_XEN zeroentry xen_hypervisor_callback xen_do_hypervisor_callback @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1605 @ paranoid_userspace: movq %rsp,%rdi /* &pt_regs */ call sync_regs movq %rax,%rsp /* switch stack for scheduling */ - testl $_TIF_NEED_RESCHED,%ebx + testl $_TIF_NEED_RESCHED_MASK,%ebx jnz paranoid_schedule movl %ebx,%edx /* arg3: thread flags */ TRACE_IRQS_ON Index: linux-3.12.19-rt30/arch/x86/kernel/irq_32.c =================================================================== --- linux-3.12.19-rt30.orig/arch/x86/kernel/irq_32.c +++ linux-3.12.19-rt30/arch/x86/kernel/irq_32.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:152 @ void irq_ctx_init(int cpu) cpu, per_cpu(hardirq_ctx, cpu), per_cpu(softirq_ctx, cpu)); } +#ifndef CONFIG_PREEMPT_RT_FULL asmlinkage void do_softirq(void) { unsigned long flags; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:183 @ asmlinkage void do_softirq(void) local_irq_restore(flags); } +#endif bool handle_irq(unsigned irq, struct pt_regs *regs) { Index: linux-3.12.19-rt30/arch/x86/kernel/irq_64.c =================================================================== --- linux-3.12.19-rt30.orig/arch/x86/kernel/irq_64.c +++ linux-3.12.19-rt30/arch/x86/kernel/irq_64.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:91 @ bool handle_irq(unsigned irq, struct pt_ return true; } - +#ifndef CONFIG_PREEMPT_RT_FULL extern void call_softirq(void); asmlinkage void do_softirq(void) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:111 @ asmlinkage void do_softirq(void) } local_irq_restore(flags); } +#endif Index: linux-3.12.19-rt30/arch/x86/kernel/irq_work.c =================================================================== --- linux-3.12.19-rt30.orig/arch/x86/kernel/irq_work.c +++ linux-3.12.19-rt30/arch/x86/kernel/irq_work.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:41 @ __visible void smp_trace_irq_work_interr exiting_irq(); } +#ifndef CONFIG_PREEMPT_RT_FULL void arch_irq_work_raise(void) { #ifdef CONFIG_X86_LOCAL_APIC @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:52 @ void arch_irq_work_raise(void) apic_wait_icr_idle(); #endif } +#endif Index: linux-3.12.19-rt30/arch/x86/kernel/process_32.c =================================================================== --- linux-3.12.19-rt30.orig/arch/x86/kernel/process_32.c +++ linux-3.12.19-rt30/arch/x86/kernel/process_32.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:39 @ #include <linux/uaccess.h> #include <linux/io.h> #include <linux/kdebug.h> +#include <linux/highmem.h> #include <asm/pgtable.h> #include <asm/ldt.h> @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:223 @ start_thread(struct pt_regs *regs, unsig } EXPORT_SYMBOL_GPL(start_thread); +#ifdef CONFIG_PREEMPT_RT_FULL +static void switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p) +{ + int i; + + /* + * Clear @prev's kmap_atomic mappings + */ + for (i = 0; i < prev_p->kmap_idx; i++) { + int idx = i + KM_TYPE_NR * smp_processor_id(); + pte_t *ptep = kmap_pte - idx; + + kpte_clear_flush(ptep, __fix_to_virt(FIX_KMAP_BEGIN + idx)); + } + /* + * Restore @next_p's kmap_atomic mappings + */ + for (i = 0; i < next_p->kmap_idx; i++) { + int idx = i + KM_TYPE_NR * smp_processor_id(); + + if (!pte_none(next_p->kmap_pte[i])) + set_pte(kmap_pte - idx, next_p->kmap_pte[i]); + } +} +#else +static inline void +switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p) { } +#endif + /* * switch_to(x,y) should switch tasks from x to y. @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:331 @ __switch_to(struct task_struct *prev_p, task_thread_info(next_p)->flags & _TIF_WORK_CTXSW_NEXT)) __switch_to_xtra(prev_p, next_p, tss); + switch_kmaps(prev_p, next_p); + /* * Leave lazy mode, flushing any hypercalls made here. * This must be done before restoring TLS segments so Index: linux-3.12.19-rt30/arch/x86/kernel/signal.c =================================================================== --- linux-3.12.19-rt30.orig/arch/x86/kernel/signal.c +++ linux-3.12.19-rt30/arch/x86/kernel/signal.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:742 @ do_notify_resume(struct pt_regs *regs, v mce_notify_process(); #endif /* CONFIG_X86_64 && CONFIG_X86_MCE */ +#ifdef ARCH_RT_DELAYS_SIGNAL_SEND + if (unlikely(current->forced_info.si_signo)) { + struct task_struct *t = current; + force_sig_info(t->forced_info.si_signo, &t->forced_info, t); + t->forced_info.si_signo = 0; + } +#endif + if (thread_info_flags & _TIF_UPROBE) uprobe_notify_resume(regs); Index: linux-3.12.19-rt30/arch/x86/kernel/traps.c =================================================================== --- linux-3.12.19-rt30.orig/arch/x86/kernel/traps.c +++ linux-3.12.19-rt30/arch/x86/kernel/traps.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:89 @ static inline void conditional_sti(struc local_irq_enable(); } -static inline void preempt_conditional_sti(struct pt_regs *regs) +static inline void conditional_sti_ist(struct pt_regs *regs) { +#ifdef CONFIG_X86_64 + /* + * X86_64 uses a per CPU stack on the IST for certain traps + * like int3. The task can not be preempted when using one + * of these stacks, thus preemption must be disabled, otherwise + * the stack can be corrupted if the task is scheduled out, + * and another task comes in and uses this stack. + * + * On x86_32 the task keeps its own stack and it is OK if the + * task schedules out. + */ inc_preempt_count(); +#endif if (regs->flags & X86_EFLAGS_IF) local_irq_enable(); } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:114 @ static inline void conditional_cli(struc local_irq_disable(); } -static inline void preempt_conditional_cli(struct pt_regs *regs) +static inline void conditional_cli_ist(struct pt_regs *regs) { if (regs->flags & X86_EFLAGS_IF) local_irq_disable(); +#ifdef CONFIG_X86_64 dec_preempt_count(); +#endif } static int __kprobes @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:253 @ dotraplinkage void do_stack_segment(stru prev_state = exception_enter(); if (notify_die(DIE_TRAP, "stack segment", regs, error_code, X86_TRAP_SS, SIGBUS) != NOTIFY_STOP) { - preempt_conditional_sti(regs); + conditional_sti_ist(regs); do_trap(X86_TRAP_SS, SIGBUS, "stack segment", regs, error_code, NULL); - preempt_conditional_cli(regs); + conditional_cli_ist(regs); } exception_exit(prev_state); } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:364 @ dotraplinkage void __kprobes notrace do_ * as we may switch to the interrupt stack. */ debug_stack_usage_inc(); - preempt_conditional_sti(regs); + conditional_sti_ist(regs); do_trap(X86_TRAP_BP, SIGTRAP, "int3", regs, error_code, NULL); - preempt_conditional_cli(regs); + conditional_cli_ist(regs); debug_stack_usage_dec(); exit: exception_exit(prev_state); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:472 @ dotraplinkage void __kprobes do_debug(st debug_stack_usage_inc(); /* It's safe to allow irq's after DR6 has been saved */ - preempt_conditional_sti(regs); + conditional_sti_ist(regs); if (regs->flags & X86_VM_MASK) { handle_vm86_trap((struct kernel_vm86_regs *) regs, error_code, X86_TRAP_DB); - preempt_conditional_cli(regs); + conditional_cli_ist(regs); debug_stack_usage_dec(); goto exit; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:497 @ dotraplinkage void __kprobes do_debug(st si_code = get_si_code(tsk->thread.debugreg6); if (tsk->thread.debugreg6 & (DR_STEP | DR_TRAP_BITS) || user_icebp) send_sigtrap(tsk, regs, error_code, si_code); - preempt_conditional_cli(regs); + conditional_cli_ist(regs); debug_stack_usage_dec(); exit: Index: linux-3.12.19-rt30/arch/x86/kvm/x86.c =================================================================== --- linux-3.12.19-rt30.orig/arch/x86/kvm/x86.c +++ linux-3.12.19-rt30/arch/x86/kvm/x86.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:5495 @ int kvm_arch_init(void *opaque) goto out; } +#ifdef CONFIG_PREEMPT_RT_FULL + if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) { + printk(KERN_ERR "RT requires X86_FEATURE_CONSTANT_TSC\n"); + return -EOPNOTSUPP; + } +#endif + r = kvm_mmu_module_init(); if (r) goto out_free_percpu; Index: linux-3.12.19-rt30/arch/x86/mm/fault.c =================================================================== --- linux-3.12.19-rt30.orig/arch/x86/mm/fault.c +++ linux-3.12.19-rt30/arch/x86/mm/fault.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1101 @ __do_page_fault(struct pt_regs *regs, un * If we're in an interrupt, have no user context or are running * in an atomic region then we must not take the fault: */ - if (unlikely(in_atomic() || !mm)) { + if (unlikely(!mm || pagefault_disabled())) { bad_area_nosemaphore(regs, error_code, address); return; } Index: linux-3.12.19-rt30/arch/x86/mm/highmem_32.c =================================================================== --- linux-3.12.19-rt30.orig/arch/x86/mm/highmem_32.c +++ linux-3.12.19-rt30/arch/x86/mm/highmem_32.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:35 @ EXPORT_SYMBOL(kunmap); */ void *kmap_atomic_prot(struct page *page, pgprot_t prot) { + pte_t pte = mk_pte(page, prot); unsigned long vaddr; int idx, type; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:49 @ void *kmap_atomic_prot(struct page *page 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)); +#ifdef CONFIG_PREEMPT_RT_FULL + current->kmap_pte[type] = pte; +#endif + set_pte(kmap_pte-idx, pte); arch_flush_lazy_mmu_mode(); return (void *)vaddr; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:95 @ void __kunmap_atomic(void *kvaddr) * is a bad idea also, in case the page changes cacheability * attributes or becomes a protected page in a hypervisor. */ +#ifdef CONFIG_PREEMPT_RT_FULL + current->kmap_pte[type] = __pte(0); +#endif kpte_clear_flush(kmap_pte-idx, vaddr); kmap_atomic_idx_pop(); arch_flush_lazy_mmu_mode(); Index: linux-3.12.19-rt30/arch/x86/mm/iomap_32.c =================================================================== --- linux-3.12.19-rt30.orig/arch/x86/mm/iomap_32.c +++ linux-3.12.19-rt30/arch/x86/mm/iomap_32.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:59 @ EXPORT_SYMBOL_GPL(iomap_free); void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot) { + pte_t pte = pfn_pte(pfn, prot); unsigned long vaddr; int idx, type; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:68 @ void *kmap_atomic_prot_pfn(unsigned long 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)); + WARN_ON(!pte_none(*(kmap_pte - idx))); + +#ifdef CONFIG_PREEMPT_RT_FULL + current->kmap_pte[type] = pte; +#endif + set_pte(kmap_pte - idx, pte); arch_flush_lazy_mmu_mode(); return (void *)vaddr; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:119 @ iounmap_atomic(void __iomem *kvaddr) * is a bad idea also, in case the page changes cacheability * attributes or becomes a protected page in a hypervisor. */ +#ifdef CONFIG_PREEMPT_RT_FULL + current->kmap_pte[type] = __pte(0); +#endif kpte_clear_flush(kmap_pte-idx, vaddr); kmap_atomic_idx_pop(); } Index: linux-3.12.19-rt30/arch/xtensa/mm/fault.c =================================================================== --- linux-3.12.19-rt30.orig/arch/xtensa/mm/fault.c +++ linux-3.12.19-rt30/arch/xtensa/mm/fault.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:60 @ void do_page_fault(struct pt_regs *regs) /* If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm) { + if (!mm || pagefault_disabled()) { bad_page_fault(regs, address, SIGSEGV); return; } Index: linux-3.12.19-rt30/block/blk-core.c =================================================================== --- linux-3.12.19-rt30.orig/block/blk-core.c +++ linux-3.12.19-rt30/block/blk-core.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:235 @ EXPORT_SYMBOL(blk_delay_queue); **/ void blk_start_queue(struct request_queue *q) { - WARN_ON(!irqs_disabled()); + WARN_ON_NONRT(!irqs_disabled()); queue_flag_clear(QUEUE_FLAG_STOPPED, q); __blk_run_queue(q); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2928 @ static void queue_unplugged(struct reque blk_run_queue_async(q); else __blk_run_queue(q); - spin_unlock(q->queue_lock); + spin_unlock_irq(q->queue_lock); } static void flush_plug_callbacks(struct blk_plug *plug, bool from_schedule) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2976 @ EXPORT_SYMBOL(blk_check_plugged); void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule) { struct request_queue *q; - unsigned long flags; struct request *rq; LIST_HEAD(list); unsigned int depth; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2993 @ void blk_flush_plug_list(struct blk_plug q = NULL; depth = 0; - /* - * Save and disable interrupts here, to avoid doing it for every - * queue lock we have to take. - */ - local_irq_save(flags); while (!list_empty(&list)) { rq = list_entry_rq(list.next); list_del_init(&rq->queuelist); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:3005 @ void blk_flush_plug_list(struct blk_plug queue_unplugged(q, depth, from_schedule); q = rq->q; depth = 0; - spin_lock(q->queue_lock); + spin_lock_irq(q->queue_lock); } /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:3032 @ void blk_flush_plug_list(struct blk_plug */ if (q) queue_unplugged(q, depth, from_schedule); - - local_irq_restore(flags); } void blk_finish_plug(struct blk_plug *plug) Index: linux-3.12.19-rt30/block/blk-ioc.c =================================================================== --- linux-3.12.19-rt30.orig/block/blk-ioc.c +++ linux-3.12.19-rt30/block/blk-ioc.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:11 @ #include <linux/blkdev.h> #include <linux/bootmem.h> /* for max_pfn/max_low_pfn */ #include <linux/slab.h> +#include <linux/delay.h> #include "blk.h" @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:114 @ static void ioc_release_fn(struct work_s spin_unlock(q->queue_lock); } else { spin_unlock_irqrestore(&ioc->lock, flags); - cpu_relax(); + cpu_chill(); spin_lock_irqsave_nested(&ioc->lock, flags, 1); } } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:192 @ retry: spin_unlock(icq->q->queue_lock); } else { spin_unlock_irqrestore(&ioc->lock, flags); - cpu_relax(); + cpu_chill(); goto retry; } } Index: linux-3.12.19-rt30/block/blk-iopoll.c =================================================================== --- linux-3.12.19-rt30.orig/block/blk-iopoll.c +++ linux-3.12.19-rt30/block/blk-iopoll.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:41 @ void blk_iopoll_sched(struct blk_iopoll list_add_tail(&iop->list, &__get_cpu_var(blk_cpu_iopoll)); __raise_softirq_irqoff(BLOCK_IOPOLL_SOFTIRQ); local_irq_restore(flags); + preempt_check_resched_rt(); } EXPORT_SYMBOL(blk_iopoll_sched); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:139 @ static void blk_iopoll_softirq(struct so __raise_softirq_irqoff(BLOCK_IOPOLL_SOFTIRQ); local_irq_enable(); + preempt_check_resched_rt(); } /** @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:209 @ static int blk_iopoll_cpu_notify(struct &__get_cpu_var(blk_cpu_iopoll)); __raise_softirq_irqoff(BLOCK_IOPOLL_SOFTIRQ); local_irq_enable(); + preempt_check_resched_rt(); } return NOTIFY_OK; Index: linux-3.12.19-rt30/block/blk-softirq.c =================================================================== --- linux-3.12.19-rt30.orig/block/blk-softirq.c +++ linux-3.12.19-rt30/block/blk-softirq.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:54 @ static void trigger_softirq(void *data) raise_softirq_irqoff(BLOCK_SOFTIRQ); local_irq_restore(flags); + preempt_check_resched_rt(); } /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:97 @ static int blk_cpu_notify(struct notifie &__get_cpu_var(blk_cpu_done)); raise_softirq_irqoff(BLOCK_SOFTIRQ); local_irq_enable(); + preempt_check_resched_rt(); } return NOTIFY_OK; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:155 @ do_local: goto do_local; local_irq_restore(flags); + preempt_check_resched_rt(); } /** Index: linux-3.12.19-rt30/crypto/algapi.c =================================================================== --- linux-3.12.19-rt30.orig/crypto/algapi.c +++ linux-3.12.19-rt30/crypto/algapi.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:687 @ EXPORT_SYMBOL_GPL(crypto_spawn_tfm2); int crypto_register_notifier(struct notifier_block *nb) { - return blocking_notifier_chain_register(&crypto_chain, nb); + return srcu_notifier_chain_register(&crypto_chain, nb); } EXPORT_SYMBOL_GPL(crypto_register_notifier); int crypto_unregister_notifier(struct notifier_block *nb) { - return blocking_notifier_chain_unregister(&crypto_chain, nb); + return srcu_notifier_chain_unregister(&crypto_chain, nb); } EXPORT_SYMBOL_GPL(crypto_unregister_notifier); Index: linux-3.12.19-rt30/crypto/api.c =================================================================== --- linux-3.12.19-rt30.orig/crypto/api.c +++ linux-3.12.19-rt30/crypto/api.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:34 @ EXPORT_SYMBOL_GPL(crypto_alg_list); DECLARE_RWSEM(crypto_alg_sem); EXPORT_SYMBOL_GPL(crypto_alg_sem); -BLOCKING_NOTIFIER_HEAD(crypto_chain); +SRCU_NOTIFIER_HEAD(crypto_chain); EXPORT_SYMBOL_GPL(crypto_chain); static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:239 @ int crypto_probing_notify(unsigned long { int ok; - ok = blocking_notifier_call_chain(&crypto_chain, val, v); + ok = srcu_notifier_call_chain(&crypto_chain, val, v); if (ok == NOTIFY_DONE) { request_module("cryptomgr"); - ok = blocking_notifier_call_chain(&crypto_chain, val, v); + ok = srcu_notifier_call_chain(&crypto_chain, val, v); } return ok; Index: linux-3.12.19-rt30/crypto/internal.h =================================================================== --- linux-3.12.19-rt30.orig/crypto/internal.h +++ linux-3.12.19-rt30/crypto/internal.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:51 @ struct crypto_larval { extern struct list_head crypto_alg_list; extern struct rw_semaphore crypto_alg_sem; -extern struct blocking_notifier_head crypto_chain; +extern struct srcu_notifier_head crypto_chain; #ifdef CONFIG_PROC_FS void __init crypto_init_proc(void); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:145 @ static inline int crypto_is_moribund(str static inline void crypto_notify(unsigned long val, void *v) { - blocking_notifier_call_chain(&crypto_chain, val, v); + srcu_notifier_call_chain(&crypto_chain, val, v); } #endif /* _CRYPTO_INTERNAL_H */ Index: linux-3.12.19-rt30/drivers/acpi/acpica/acglobal.h =================================================================== --- linux-3.12.19-rt30.orig/drivers/acpi/acpica/acglobal.h +++ linux-3.12.19-rt30/drivers/acpi/acpica/acglobal.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:238 @ ACPI_EXTERN u8 acpi_gbl_global_lock_pend * interrupt level */ ACPI_EXTERN acpi_spinlock acpi_gbl_gpe_lock; /* For GPE data structs and registers */ -ACPI_EXTERN acpi_spinlock acpi_gbl_hardware_lock; /* For ACPI H/W except GPE registers */ +ACPI_EXTERN acpi_raw_spinlock acpi_gbl_hardware_lock; /* For ACPI H/W except GPE registers */ ACPI_EXTERN acpi_spinlock acpi_gbl_reference_count_lock; /* Mutex for _OSI support */ Index: linux-3.12.19-rt30/drivers/acpi/acpica/hwregs.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/acpi/acpica/hwregs.c +++ linux-3.12.19-rt30/drivers/acpi/acpica/hwregs.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:272 @ acpi_status acpi_hw_clear_acpi_status(vo ACPI_BITMASK_ALL_FIXED_STATUS, ACPI_FORMAT_UINT64(acpi_gbl_xpm1a_status.address))); - lock_flags = acpi_os_acquire_lock(acpi_gbl_hardware_lock); + raw_spin_lock_irqsave(acpi_gbl_hardware_lock, lock_flags); /* Clear the fixed events in PM1 A/B */ status = acpi_hw_register_write(ACPI_REGISTER_PM1_STATUS, ACPI_BITMASK_ALL_FIXED_STATUS); - acpi_os_release_lock(acpi_gbl_hardware_lock, lock_flags); + raw_spin_unlock_irqrestore(acpi_gbl_hardware_lock, lock_flags); if (ACPI_FAILURE(status)) goto exit; Index: linux-3.12.19-rt30/drivers/acpi/acpica/hwxface.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/acpi/acpica/hwxface.c +++ linux-3.12.19-rt30/drivers/acpi/acpica/hwxface.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:368 @ acpi_status acpi_write_bit_register(u32 return_ACPI_STATUS(AE_BAD_PARAMETER); } - lock_flags = acpi_os_acquire_lock(acpi_gbl_hardware_lock); + raw_spin_lock_irqsave(acpi_gbl_hardware_lock, lock_flags); /* * At this point, we know that the parent register is one of the @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:429 @ acpi_status acpi_write_bit_register(u32 unlock_and_exit: - acpi_os_release_lock(acpi_gbl_hardware_lock, lock_flags); + raw_spin_unlock_irqrestore(acpi_gbl_hardware_lock, lock_flags); return_ACPI_STATUS(status); } Index: linux-3.12.19-rt30/drivers/acpi/acpica/utmutex.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/acpi/acpica/utmutex.c +++ linux-3.12.19-rt30/drivers/acpi/acpica/utmutex.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:91 @ acpi_status acpi_ut_mutex_initialize(voi return_ACPI_STATUS (status); } - status = acpi_os_create_lock (&acpi_gbl_hardware_lock); + status = acpi_os_create_raw_lock (&acpi_gbl_hardware_lock); if (ACPI_FAILURE (status)) { return_ACPI_STATUS (status); } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:144 @ void acpi_ut_mutex_terminate(void) /* Delete the spinlocks */ acpi_os_delete_lock(acpi_gbl_gpe_lock); - acpi_os_delete_lock(acpi_gbl_hardware_lock); + acpi_os_delete_raw_lock(acpi_gbl_hardware_lock); acpi_os_delete_lock(acpi_gbl_reference_count_lock); /* Delete the reader/writer lock */ Index: linux-3.12.19-rt30/drivers/ata/libata-sff.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/ata/libata-sff.c +++ linux-3.12.19-rt30/drivers/ata/libata-sff.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:681 @ unsigned int ata_sff_data_xfer_noirq(str unsigned long flags; unsigned int consumed; - local_irq_save(flags); + local_irq_save_nort(flags); consumed = ata_sff_data_xfer32(dev, buf, buflen, rw); - local_irq_restore(flags); + local_irq_restore_nort(flags); return consumed; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:722 @ static void ata_pio_sector(struct ata_qu unsigned long flags; /* FIXME: use a bounce buffer */ - local_irq_save(flags); + local_irq_save_nort(flags); buf = kmap_atomic(page); /* do the actual data transfer */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:730 @ static void ata_pio_sector(struct ata_qu do_write); kunmap_atomic(buf); - local_irq_restore(flags); + local_irq_restore_nort(flags); } else { buf = page_address(page); ap->ops->sff_data_xfer(qc->dev, buf + offset, qc->sect_size, @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:867 @ next_sg: unsigned long flags; /* FIXME: use bounce buffer */ - local_irq_save(flags); + local_irq_save_nort(flags); buf = kmap_atomic(page); /* do the actual data transfer */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:875 @ next_sg: count, rw); kunmap_atomic(buf); - local_irq_restore(flags); + local_irq_restore_nort(flags); } else { buf = page_address(page); consumed = ap->ops->sff_data_xfer(dev, buf + offset, Index: linux-3.12.19-rt30/drivers/char/random.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/char/random.c +++ linux-3.12.19-rt30/drivers/char/random.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:676 @ static void add_timer_randomness(struct preempt_disable(); /* if over the trickle threshold, use only 1 in 4096 samples */ if (input_pool.entropy_count > trickle_thresh && - ((__this_cpu_inc_return(trickle_count) - 1) & 0xfff)) - goto out; + ((__this_cpu_inc_return(trickle_count) - 1) & 0xfff)) { + preempt_enable(); + return; + } + preempt_enable(); sample.jiffies = jiffies; sample.cycles = random_get_entropy(); sample.num = num; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:722 @ static void add_timer_randomness(struct credit_entropy_bits(&input_pool, min_t(int, fls(delta>>1), 11)); } -out: - preempt_enable(); } void add_input_randomness(unsigned int type, unsigned int code, @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:742 @ EXPORT_SYMBOL_GPL(add_input_randomness); static DEFINE_PER_CPU(struct fast_pool, irq_randomness); -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 = &__get_cpu_var(irq_randomness); - struct pt_regs *regs = get_irq_regs(); unsigned long now = jiffies; __u32 input[4], cycles = random_get_entropy(); input[0] = cycles ^ jiffies; input[1] = irq; - if (regs) { - __u64 ip = instruction_pointer(regs); + if (ip) { input[2] = ip; input[3] = ip >> 32; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:765 @ void add_interrupt_randomness(int irq, i fast_pool->last = now; r = nonblocking_pool.initialized ? &input_pool : &nonblocking_pool; +#ifndef CONFIG_PREEMPT_RT_FULL __mix_pool_bytes(r, &fast_pool->pool, sizeof(fast_pool->pool), NULL); +#else + mix_pool_bytes(r, &fast_pool->pool, sizeof(fast_pool->pool), NULL); +#endif /* * If we don't have a valid cycle counter, and we see * back-to-back timer interrupts, then skip giving credit for Index: linux-3.12.19-rt30/drivers/clocksource/tcb_clksrc.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/clocksource/tcb_clksrc.c +++ linux-3.12.19-rt30/drivers/clocksource/tcb_clksrc.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:26 @ * this 32 bit free-running counter. the second channel is not used. * * - The third channel may be used to provide a 16-bit clockevent - * source, used in either periodic or oneshot mode. This runs - * at 32 KiHZ, and can handle delays of up to two seconds. + * source, used in either periodic or oneshot mode. * * A boot clocksource and clockevent source are also currently needed, * unless the relevant platforms (ARM/AT91, AVR32/AT32) are changed so @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:76 @ static struct clocksource clksrc = { struct tc_clkevt_device { struct clock_event_device clkevt; struct clk *clk; + u32 freq; void __iomem *regs; }; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:85 @ static struct tc_clkevt_device *to_tc_cl return container_of(clkevt, struct tc_clkevt_device, clkevt); } -/* For now, we always use the 32K clock ... this optimizes for NO_HZ, - * because using one of the divided clocks would usually mean the - * tick rate can never be less than several dozen Hz (vs 0.5 Hz). - * - * A divided clock could be good for high resolution timers, since - * 30.5 usec resolution can seem "low". - */ static u32 timer_clock; static void tc_mode(enum clock_event_mode m, struct clock_event_device *d) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:107 @ static void tc_mode(enum clock_event_mod case CLOCK_EVT_MODE_PERIODIC: clk_enable(tcd->clk); - /* slow clock, count up to RC, then irq and restart */ + /* count up to RC, then irq and restart */ __raw_writel(timer_clock | ATMEL_TC_WAVE | ATMEL_TC_WAVESEL_UP_AUTO, regs + ATMEL_TC_REG(2, CMR)); - __raw_writel((32768 + HZ/2) / HZ, tcaddr + ATMEL_TC_REG(2, RC)); + __raw_writel((tcd->freq + HZ/2)/HZ, + tcaddr + ATMEL_TC_REG(2, RC)); /* Enable clock and interrupts on RC compare */ __raw_writel(ATMEL_TC_CPCS, regs + ATMEL_TC_REG(2, IER)); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:125 @ static void tc_mode(enum clock_event_mod case CLOCK_EVT_MODE_ONESHOT: clk_enable(tcd->clk); - /* slow clock, count up to RC, then irq and stop */ + /* count up to RC, then irq and stop */ __raw_writel(timer_clock | ATMEL_TC_CPCSTOP | ATMEL_TC_WAVE | ATMEL_TC_WAVESEL_UP_AUTO, regs + ATMEL_TC_REG(2, CMR)); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:154 @ static struct tc_clkevt_device clkevt = .name = "tc_clkevt", .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, +#ifdef CONFIG_ATMEL_TCB_CLKSRC_USE_SLOW_CLOCK /* Should be lower than at91rm9200's system timer */ .rating = 125, +#else + .rating = 200, +#endif .set_next_event = tc_next_event, .set_mode = tc_mode, }, @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:185 @ static struct irqaction tc_irqaction = { .handler = ch2_irq, }; -static void __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx) +static void __init setup_clkevents(struct atmel_tc *tc, int divisor_idx) { + unsigned divisor = atmel_tc_divisors[divisor_idx]; struct clk *t2_clk = tc->clk[2]; int irq = tc->irq[2]; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:195 @ static void __init setup_clkevents(struc clkevt.clk = t2_clk; tc_irqaction.dev_id = &clkevt; - timer_clock = clk32k_divisor_idx; + timer_clock = divisor_idx; + if (!divisor) + clkevt.freq = 32768; + else + clkevt.freq = clk_get_rate(t2_clk) / divisor; clkevt.clkevt.cpumask = cpumask_of(0); - clockevents_config_and_register(&clkevt.clkevt, 32768, 1, 0xffff); + clockevents_config_and_register(&clkevt.clkevt, clkevt.freq, 1, 0xffff); setup_irq(irq, &tc_irqaction); } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:328 @ static int __init tcb_clksrc_init(void) clocksource_register_hz(&clksrc, divided_rate); /* channel 2: periodic and oneshot timer support */ +#ifdef CONFIG_ATMEL_TCB_CLKSRC_USE_SLOW_CLOCK setup_clkevents(tc, clk32k_divisor_idx); - +#else + setup_clkevents(tc, best_divisor_idx); +#endif return 0; } arch_initcall(tcb_clksrc_init); Index: linux-3.12.19-rt30/drivers/gpu/drm/drm_irq.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/gpu/drm/drm_irq.c +++ linux-3.12.19-rt30/drivers/gpu/drm/drm_irq.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:631 @ int drm_calc_vbltimestamp_from_scanoutpo * code gets preempted or delayed for some reason. */ for (i = 0; i < DRM_TIMESTAMP_MAXRETRIES; i++) { - /* Disable preemption to make it very likely to - * succeed in the first iteration even on PREEMPT_RT kernel. - */ - preempt_disable(); - /* Get system timestamp before query. */ stime = ktime_get(); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:642 @ int drm_calc_vbltimestamp_from_scanoutpo if (!drm_timestamp_monotonic) mono_time_offset = ktime_get_monotonic_offset(); - preempt_enable(); - /* Return as no-op if scanout query unsupported or failed. */ if (!(vbl_status & DRM_SCANOUTPOS_VALID)) { DRM_DEBUG("crtc %d : scanoutpos query failed [%d].\n", Index: linux-3.12.19-rt30/drivers/gpu/drm/i915/i915_gem.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/gpu/drm/i915/i915_gem.c +++ linux-3.12.19-rt30/drivers/gpu/drm/i915/i915_gem.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:4798 @ static bool mutex_is_locked_by(struct mu if (!mutex_is_locked(mutex)) return false; -#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_MUTEXES) +#if (defined(CONFIG_SMP) || defined(CONFIG_DEBUG_MUTEXES)) && !defined(CONFIG_PREEMPT_RT_BASE) return mutex->owner == task; #else /* Since UP may be pre-empted, we cannot assume that we own the lock */ Index: linux-3.12.19-rt30/drivers/gpu/drm/i915/i915_gem_execbuffer.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/gpu/drm/i915/i915_gem_execbuffer.c +++ linux-3.12.19-rt30/drivers/gpu/drm/i915/i915_gem_execbuffer.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1132 @ i915_gem_do_execbuffer(struct drm_device goto err; } +#ifndef CONFIG_PREEMPT_RT_BASE trace_i915_gem_ring_dispatch(ring, intel_ring_get_seqno(ring), flags); +#endif i915_gem_execbuffer_move_to_active(&eb->objects, vm, ring); i915_gem_execbuffer_retire_commands(dev, file, ring, batch_obj); Index: linux-3.12.19-rt30/drivers/i2c/busses/i2c-omap.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/i2c/busses/i2c-omap.c +++ linux-3.12.19-rt30/drivers/i2c/busses/i2c-omap.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:882 @ omap_i2c_isr(int irq, void *dev_id) u16 mask; u16 stat; - spin_lock(&dev->lock); - mask = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG); stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG); + mask = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG); if (stat & mask) ret = IRQ_WAKE_THREAD; - spin_unlock(&dev->lock); - return ret; } Index: linux-3.12.19-rt30/drivers/ide/alim15x3.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/ide/alim15x3.c +++ linux-3.12.19-rt30/drivers/ide/alim15x3.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:237 @ static int init_chipset_ali15x3(struct p isa_dev = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1533, NULL); - local_irq_save(flags); + local_irq_save_nort(flags); if (m5229_revision < 0xC2) { /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:328 @ out: } pci_dev_put(north); pci_dev_put(isa_dev); - local_irq_restore(flags); + local_irq_restore_nort(flags); return 0; } Index: linux-3.12.19-rt30/drivers/ide/hpt366.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/ide/hpt366.c +++ linux-3.12.19-rt30/drivers/ide/hpt366.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1244 @ static int init_dma_hpt366(ide_hwif_t *h dma_old = inb(base + 2); - local_irq_save(flags); + local_irq_save_nort(flags); dma_new = dma_old; pci_read_config_byte(dev, hwif->channel ? 0x4b : 0x43, &masterdma); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1255 @ static int init_dma_hpt366(ide_hwif_t *h if (dma_new != dma_old) outb(dma_new, base + 2); - local_irq_restore(flags); + local_irq_restore_nort(flags); printk(KERN_INFO " %s: BM-DMA at 0x%04lx-0x%04lx\n", hwif->name, base, base + 7); Index: linux-3.12.19-rt30/drivers/ide/ide-io-std.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/ide/ide-io-std.c +++ linux-3.12.19-rt30/drivers/ide/ide-io-std.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:178 @ void ide_input_data(ide_drive_t *drive, unsigned long uninitialized_var(flags); if ((io_32bit & 2) && !mmio) { - local_irq_save(flags); + local_irq_save_nort(flags); ata_vlb_sync(io_ports->nsect_addr); } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:189 @ void ide_input_data(ide_drive_t *drive, insl(data_addr, buf, words); if ((io_32bit & 2) && !mmio) - local_irq_restore(flags); + local_irq_restore_nort(flags); if (((len + 1) & 3) < 2) return; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:222 @ void ide_output_data(ide_drive_t *drive, unsigned long uninitialized_var(flags); if ((io_32bit & 2) && !mmio) { - local_irq_save(flags); + local_irq_save_nort(flags); ata_vlb_sync(io_ports->nsect_addr); } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:233 @ void ide_output_data(ide_drive_t *drive, outsl(data_addr, buf, words); if ((io_32bit & 2) && !mmio) - local_irq_restore(flags); + local_irq_restore_nort(flags); if (((len + 1) & 3) < 2) return; Index: linux-3.12.19-rt30/drivers/ide/ide-io.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/ide/ide-io.c +++ linux-3.12.19-rt30/drivers/ide/ide-io.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:662 @ void ide_timer_expiry (unsigned long dat /* disable_irq_nosync ?? */ disable_irq(hwif->irq); /* local CPU only, as if we were handling an interrupt */ - local_irq_disable(); + local_irq_disable_nort(); if (hwif->polling) { startstop = handler(drive); } else if (drive_is_ready(drive)) { Index: linux-3.12.19-rt30/drivers/ide/ide-iops.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/ide/ide-iops.c +++ linux-3.12.19-rt30/drivers/ide/ide-iops.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:132 @ int __ide_wait_stat(ide_drive_t *drive, if ((stat & ATA_BUSY) == 0) break; - local_irq_restore(flags); + local_irq_restore_nort(flags); *rstat = stat; return -EBUSY; } } - local_irq_restore(flags); + local_irq_restore_nort(flags); } /* * Allow status to settle, then read it again. Index: linux-3.12.19-rt30/drivers/ide/ide-probe.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/ide/ide-probe.c +++ linux-3.12.19-rt30/drivers/ide/ide-probe.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:199 @ static void do_identify(ide_drive_t *dri int bswap = 1; /* local CPU only; some systems need this */ - local_irq_save(flags); + local_irq_save_nort(flags); /* read 512 bytes of id info */ hwif->tp_ops->input_data(drive, NULL, id, SECTOR_SIZE); - local_irq_restore(flags); + local_irq_restore_nort(flags); drive->dev_flags |= IDE_DFLAG_ID_READ; #ifdef DEBUG Index: linux-3.12.19-rt30/drivers/ide/ide-taskfile.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/ide/ide-taskfile.c +++ linux-3.12.19-rt30/drivers/ide/ide-taskfile.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:253 @ void ide_pio_bytes(ide_drive_t *drive, s page_is_high = PageHighMem(page); if (page_is_high) - local_irq_save(flags); + local_irq_save_nort(flags); buf = kmap_atomic(page) + offset; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:274 @ void ide_pio_bytes(ide_drive_t *drive, s kunmap_atomic(buf); if (page_is_high) - local_irq_restore(flags); + local_irq_restore_nort(flags); len -= nr_bytes; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:417 @ static ide_startstop_t pre_task_out_intr } if ((drive->dev_flags & IDE_DFLAG_UNMASK) == 0) - local_irq_disable(); + local_irq_disable_nort(); ide_set_handler(drive, &task_pio_intr, WAIT_WORSTCASE); Index: linux-3.12.19-rt30/drivers/infiniband/ulp/ipoib/ipoib_multicast.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/infiniband/ulp/ipoib/ipoib_multicast.c +++ linux-3.12.19-rt30/drivers/infiniband/ulp/ipoib/ipoib_multicast.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:786 @ void ipoib_mcast_restart_task(struct wor ipoib_mcast_stop_thread(dev, 0); - local_irq_save(flags); + local_irq_save_nort(flags); netif_addr_lock(dev); spin_lock(&priv->lock); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:868 @ void ipoib_mcast_restart_task(struct wor spin_unlock(&priv->lock); netif_addr_unlock(dev); - local_irq_restore(flags); + local_irq_restore_nort(flags); /* We have to cancel outside of the spinlock */ list_for_each_entry_safe(mcast, tmcast, &remove_list, list) { Index: linux-3.12.19-rt30/drivers/input/gameport/gameport.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/input/gameport/gameport.c +++ linux-3.12.19-rt30/drivers/input/gameport/gameport.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:90 @ static int gameport_measure_speed(struct tx = 1 << 30; for(i = 0; i < 50; i++) { - local_irq_save(flags); + local_irq_save_nort(flags); GET_TIME(t1); for (t = 0; t < 50; t++) gameport_read(gameport); GET_TIME(t2); GET_TIME(t3); - local_irq_restore(flags); + local_irq_restore_nort(flags); udelay(i * 10); if ((t = DELTA(t2,t1) - DELTA(t3,t2)) < tx) tx = t; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:114 @ static int gameport_measure_speed(struct tx = 1 << 30; for(i = 0; i < 50; i++) { - local_irq_save(flags); + local_irq_save_nort(flags); rdtscl(t1); for (t = 0; t < 50; t++) gameport_read(gameport); rdtscl(t2); - local_irq_restore(flags); + local_irq_restore_nort(flags); udelay(i * 10); if (t2 - t1 < tx) tx = t2 - t1; } Index: linux-3.12.19-rt30/drivers/leds/trigger/Kconfig =================================================================== --- linux-3.12.19-rt30.orig/drivers/leds/trigger/Kconfig +++ linux-3.12.19-rt30/drivers/leds/trigger/Kconfig @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:64 @ config LEDS_TRIGGER_BACKLIGHT config LEDS_TRIGGER_CPU bool "LED CPU Trigger" - depends on LEDS_TRIGGERS + depends on LEDS_TRIGGERS && !PREEMPT_RT_BASE 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 Index: linux-3.12.19-rt30/drivers/md/bcache/Kconfig =================================================================== --- linux-3.12.19-rt30.orig/drivers/md/bcache/Kconfig +++ linux-3.12.19-rt30/drivers/md/bcache/Kconfig @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:4 @ config BCACHE tristate "Block device as cache" + depends on !PREEMPT_RT_FULL ---help--- Allows a block device to be used as cache for other devices; uses a btree for indexing and the layout is optimized for SSDs. Index: linux-3.12.19-rt30/drivers/md/dm.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/md/dm.c +++ linux-3.12.19-rt30/drivers/md/dm.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1816 @ static void dm_request_fn(struct request if (map_request(ti, clone, md)) goto requeued; - BUG_ON(!irqs_disabled()); + BUG_ON_NONRT(!irqs_disabled()); spin_lock(q->queue_lock); } goto out; requeued: - BUG_ON(!irqs_disabled()); + BUG_ON_NONRT(!irqs_disabled()); spin_lock(q->queue_lock); delay_and_out: Index: linux-3.12.19-rt30/drivers/md/raid5.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/md/raid5.c +++ linux-3.12.19-rt30/drivers/md/raid5.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1548 @ static void raid_run_ops(struct stripe_h 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++; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1602 @ static void raid_run_ops(struct stripe_h 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 int grow_one_stripe(struct r5conf *conf) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:5467 @ static int raid5_alloc_percpu(struct r5c __func__, cpu); break; } + spin_lock_init(&per_cpu_ptr(conf->percpu, cpu)->lock); } put_online_cpus(); Index: linux-3.12.19-rt30/drivers/md/raid5.h =================================================================== --- linux-3.12.19-rt30.orig/drivers/md/raid5.h +++ linux-3.12.19-rt30/drivers/md/raid5.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:447 @ 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 Index: linux-3.12.19-rt30/drivers/misc/Kconfig =================================================================== --- linux-3.12.19-rt30.orig/drivers/misc/Kconfig +++ linux-3.12.19-rt30/drivers/misc/Kconfig @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:66 @ config ATMEL_PWM config ATMEL_TCLIB bool "Atmel AT32/AT91 Timer/Counter Library" depends on (AVR32 || ARCH_AT91) + default y if PREEMPT_RT_FULL help Select this if you want a library to allocate the Timer/Counter blocks found on many Atmel processors. This facilitates using @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:82 @ config ATMEL_TCB_CLKSRC are combined to make a single 32-bit timer. When GENERIC_CLOCKEVENTS is defined, the third timer channel - may be used as a clock event device supporting oneshot mode - (delays of up to two seconds) based on the 32 KiHz clock. + may be used as a clock event device supporting oneshot mode. config ATMEL_TCB_CLKSRC_BLOCK int @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:96 @ config ATMEL_TCB_CLKSRC_BLOCK TC can be used for other purposes, such as PWM generation and interval timing. +config ATMEL_TCB_CLKSRC_USE_SLOW_CLOCK + bool "TC Block use 32 KiHz clock" + depends on ATMEL_TCB_CLKSRC + default y if !PREEMPT_RT_FULL + help + Select this to use 32 KiHz base clock rate as TC block clock + source for clock events. + + config DUMMY_IRQ tristate "Dummy IRQ handler" default n @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:134 @ config IBM_ASM for information on the specific driver level and support statement for your IBM server. +config HWLAT_DETECTOR + tristate "Testing module to detect hardware-induced latencies" + depends on DEBUG_FS + depends on RING_BUFFER + default m + ---help--- + A simple hardware latency detector. Use this module to detect + large latencies introduced by the behavior of the underlying + system firmware external to Linux. We do this using periodic + use of stop_machine to grab all available CPUs and measure + for unexplainable gaps in the CPU timestamp counter(s). By + default, the module is not enabled until the "enable" file + within the "hwlat_detector" debugfs directory is toggled. + + This module is often used to detect SMI (System Management + Interrupts) on x86 systems, though is not x86 specific. To + this end, we default to using a sample window of 1 second, + during which we will sample for 0.5 seconds. If an SMI or + similar event occurs during that time, it is recorded + into an 8K samples global ring buffer until retreived. + + WARNING: This software should never be enabled (it can be built + but should not be turned on after it is loaded) in a production + environment where high latencies are a concern since the + sampling mechanism actually introduces latencies for + regular tasks while the CPU(s) are being held. + + If unsure, say N + config PHANTOM tristate "Sensable PHANToM (PCI)" depends on PCI Index: linux-3.12.19-rt30/drivers/misc/Makefile =================================================================== --- linux-3.12.19-rt30.orig/drivers/misc/Makefile +++ linux-3.12.19-rt30/drivers/misc/Makefile @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:56 @ obj-$(CONFIG_INTEL_MEI) += mei/ obj-$(CONFIG_VMWARE_VMCI) += vmw_vmci/ obj-$(CONFIG_LATTICE_ECP3_CONFIG) += lattice-ecp3-config.o obj-$(CONFIG_SRAM) += sram.o +obj-$(CONFIG_HWLAT_DETECTOR) += hwlat_detector.o Index: linux-3.12.19-rt30/drivers/misc/hwlat_detector.c =================================================================== --- /dev/null +++ linux-3.12.19-rt30/drivers/misc/hwlat_detector.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:4 @ +/* + * hwlat_detector.c - A simple Hardware Latency detector. + * + * Use this module to detect large system latencies induced by the behavior of + * certain underlying system hardware or firmware, independent of Linux itself. + * The code was developed originally to detect the presence of SMIs on Intel + * and AMD systems, although there is no dependency upon x86 herein. + * + * The classical example usage of this module is in detecting the presence of + * SMIs or System Management Interrupts on Intel and AMD systems. An SMI is a + * somewhat special form of hardware interrupt spawned from earlier CPU debug + * modes in which the (BIOS/EFI/etc.) firmware arranges for the South Bridge + * LPC (or other device) to generate a special interrupt under certain + * circumstances, for example, upon expiration of a special SMI timer device, + * due to certain external thermal readings, on certain I/O address accesses, + * and other situations. An SMI hits a special CPU pin, triggers a special + * SMI mode (complete with special memory map), and the OS is unaware. + * + * Although certain hardware-inducing latencies are necessary (for example, + * a modern system often requires an SMI handler for correct thermal control + * and remote management) they can wreak havoc upon any OS-level performance + * guarantees toward low-latency, especially when the OS is not even made + * aware of the presence of these interrupts. For this reason, we need a + * somewhat brute force mechanism to detect these interrupts. In this case, + * we do it by hogging all of the CPU(s) for configurable timer intervals, + * sampling the built-in CPU timer, looking for discontiguous readings. + * + * WARNING: This implementation necessarily introduces latencies. Therefore, + * you should NEVER use this module in a production environment + * requiring any kind of low-latency performance guarantee(s). + * + * Copyright (C) 2008-2009 Jon Masters, Red Hat, Inc. <jcm@redhat.com> + * + * Includes useful feedback from Clark Williams <clark@redhat.com> + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/ring_buffer.h> +#include <linux/time.h> +#include <linux/hrtimer.h> +#include <linux/kthread.h> +#include <linux/debugfs.h> +#include <linux/seq_file.h> +#include <linux/uaccess.h> +#include <linux/version.h> +#include <linux/delay.h> +#include <linux/slab.h> +#include <linux/trace_clock.h> + +#define BUF_SIZE_DEFAULT 262144UL /* 8K*(sizeof(entry)) */ +#define BUF_FLAGS (RB_FL_OVERWRITE) /* no block on full */ +#define U64STR_SIZE 22 /* 20 digits max */ + +#define VERSION "1.0.0" +#define BANNER "hwlat_detector: " +#define DRVNAME "hwlat_detector" +#define DEFAULT_SAMPLE_WINDOW 1000000 /* 1s */ +#define DEFAULT_SAMPLE_WIDTH 500000 /* 0.5s */ +#define DEFAULT_LAT_THRESHOLD 10 /* 10us */ + +/* Module metadata */ + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Jon Masters <jcm@redhat.com>"); +MODULE_DESCRIPTION("A simple hardware latency detector"); +MODULE_VERSION(VERSION); + +/* Module parameters */ + +static int debug; +static int enabled; +static int threshold; + +module_param(debug, int, 0); /* enable debug */ +module_param(enabled, int, 0); /* enable detector */ +module_param(threshold, int, 0); /* latency threshold */ + +/* Buffering and sampling */ + +static struct ring_buffer *ring_buffer; /* sample buffer */ +static DEFINE_MUTEX(ring_buffer_mutex); /* lock changes */ +static unsigned long buf_size = BUF_SIZE_DEFAULT; +static struct task_struct *kthread; /* sampling thread */ + +/* DebugFS filesystem entries */ + +static struct dentry *debug_dir; /* debugfs directory */ +static struct dentry *debug_max; /* maximum TSC delta */ +static struct dentry *debug_count; /* total detect count */ +static struct dentry *debug_sample_width; /* sample width us */ +static struct dentry *debug_sample_window; /* sample window us */ +static struct dentry *debug_sample; /* raw samples us */ +static struct dentry *debug_threshold; /* threshold us */ +static struct dentry *debug_enable; /* enable/disable */ + +/* Individual samples and global state */ + +struct sample; /* latency sample */ +struct data; /* Global state */ + +/* Sampling functions */ +static int __buffer_add_sample(struct sample *sample); +static struct sample *buffer_get_sample(struct sample *sample); + +/* Threading and state */ +static int kthread_fn(void *unused); +static int start_kthread(void); +static int stop_kthread(void); +static void __reset_stats(void); +static int init_stats(void); + +/* Debugfs interface */ +static ssize_t simple_data_read(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos, const u64 *entry); +static ssize_t simple_data_write(struct file *filp, const char __user *ubuf, + size_t cnt, loff_t *ppos, u64 *entry); +static int debug_sample_fopen(struct inode *inode, struct file *filp); +static ssize_t debug_sample_fread(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos); +static int debug_sample_release(struct inode *inode, struct file *filp); +static int debug_enable_fopen(struct inode *inode, struct file *filp); +static ssize_t debug_enable_fread(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos); +static ssize_t debug_enable_fwrite(struct file *file, + const char __user *user_buffer, + size_t user_size, loff_t *offset); + +/* Initialization functions */ +static int init_debugfs(void); +static void free_debugfs(void); +static int detector_init(void); +static void detector_exit(void); + +/* Individual latency samples are stored here when detected and packed into + * the ring_buffer circular buffer, where they are overwritten when + * more than buf_size/sizeof(sample) samples are received. */ +struct sample { + u64 seqnum; /* unique sequence */ + u64 duration; /* ktime delta */ + u64 outer_duration; /* ktime delta (outer loop) */ + struct timespec timestamp; /* wall time */ + unsigned long lost; +}; + +/* keep the global state somewhere. */ +static struct data { + + struct mutex lock; /* protect changes */ + + u64 count; /* total since reset */ + u64 max_sample; /* max hardware latency */ + u64 threshold; /* sample threshold level */ + + u64 sample_window; /* total sampling window (on+off) */ + u64 sample_width; /* active sampling portion of window */ + + atomic_t sample_open; /* whether the sample file is open */ + + wait_queue_head_t wq; /* waitqeue for new sample values */ + +} data; + +/** + * __buffer_add_sample - add a new latency sample recording to the ring buffer + * @sample: The new latency sample value + * + * This receives a new latency sample and records it in a global ring buffer. + * No additional locking is used in this case. + */ +static int __buffer_add_sample(struct sample *sample) +{ + return ring_buffer_write(ring_buffer, + sizeof(struct sample), sample); +} + +/** + * buffer_get_sample - remove a hardware latency sample from the ring buffer + * @sample: Pre-allocated storage for the sample + * + * This retrieves a hardware latency sample from the global circular buffer + */ +static struct sample *buffer_get_sample(struct sample *sample) +{ + struct ring_buffer_event *e = NULL; + struct sample *s = NULL; + unsigned int cpu = 0; + + if (!sample) + return NULL; + + mutex_lock(&ring_buffer_mutex); + for_each_online_cpu(cpu) { + e = ring_buffer_consume(ring_buffer, cpu, NULL, &sample->lost); + if (e) + break; + } + + if (e) { + s = ring_buffer_event_data(e); + memcpy(sample, s, sizeof(struct sample)); + } else + sample = NULL; + mutex_unlock(&ring_buffer_mutex); + + return sample; +} + +#ifndef CONFIG_TRACING +#define time_type ktime_t +#define time_get() ktime_get() +#define time_to_us(x) ktime_to_us(x) +#define time_sub(a, b) ktime_sub(a, b) +#define init_time(a, b) (a).tv64 = b +#define time_u64(a) ((a).tv64) +#else +#define time_type u64 +#define time_get() trace_clock_local() +#define time_to_us(x) div_u64(x, 1000) +#define time_sub(a, b) ((a) - (b)) +#define init_time(a, b) (a = b) +#define time_u64(a) a +#endif +/** + * get_sample - sample the CPU TSC and look for likely hardware latencies + * + * Used to repeatedly capture the CPU TSC (or similar), looking for potential + * hardware-induced latency. Called with interrupts disabled and with + * data.lock held. + */ +static int get_sample(void) +{ + time_type start, t1, t2, last_t2; + s64 diff, total = 0; + u64 sample = 0; + u64 outer_sample = 0; + int ret = -1; + + init_time(last_t2, 0); + start = time_get(); /* start timestamp */ + + do { + + t1 = time_get(); /* we'll look for a discontinuity */ + t2 = time_get(); + + if (time_u64(last_t2)) { + /* Check the delta from outer loop (t2 to next t1) */ + diff = time_to_us(time_sub(t1, last_t2)); + /* This shouldn't happen */ + if (diff < 0) { + pr_err(BANNER "time running backwards\n"); + goto out; + } + if (diff > outer_sample) + outer_sample = diff; + } + last_t2 = t2; + + total = time_to_us(time_sub(t2, start)); /* sample width */ + + /* This checks the inner loop (t1 to t2) */ + diff = time_to_us(time_sub(t2, t1)); /* current diff */ + + /* This shouldn't happen */ + if (diff < 0) { + pr_err(BANNER "time running backwards\n"); + goto out; + } + + if (diff > sample) + sample = diff; /* only want highest value */ + + } while (total <= data.sample_width); + + ret = 0; + + /* If we exceed the threshold value, we have found a hardware latency */ + if (sample > data.threshold || outer_sample > data.threshold) { + struct sample s; + + ret = 1; + + data.count++; + s.seqnum = data.count; + s.duration = sample; + s.outer_duration = outer_sample; + s.timestamp = CURRENT_TIME; + __buffer_add_sample(&s); + + /* Keep a running maximum ever recorded hardware latency */ + if (sample > data.max_sample) + data.max_sample = sample; + } + +out: + return ret; +} + +/* + * kthread_fn - The CPU time sampling/hardware latency detection kernel thread + * @unused: A required part of the kthread API. + * + * Used to periodically sample the CPU TSC via a call to get_sample. We + * disable interrupts, which does (intentionally) introduce latency since we + * need to ensure nothing else might be running (and thus pre-empting). + * Obviously this should never be used in production environments. + * + * Currently this runs on which ever CPU it was scheduled on, but most + * real-worald hardware latency situations occur across several CPUs, + * but we might later generalize this if we find there are any actualy + * systems with alternate SMI delivery or other hardware latencies. + */ +static int kthread_fn(void *unused) +{ + int ret; + u64 interval; + + while (!kthread_should_stop()) { + + mutex_lock(&data.lock); + + local_irq_disable(); + ret = get_sample(); + local_irq_enable(); + + if (ret > 0) + wake_up(&data.wq); /* wake up reader(s) */ + + interval = data.sample_window - data.sample_width; + do_div(interval, USEC_PER_MSEC); /* modifies interval value */ + + mutex_unlock(&data.lock); + + if (msleep_interruptible(interval)) + break; + } + + return 0; +} + +/** + * start_kthread - Kick off the hardware latency sampling/detector kthread + * + * This starts a kernel thread that will sit and sample the CPU timestamp + * counter (TSC or similar) and look for potential hardware latencies. + */ +static int start_kthread(void) +{ + kthread = kthread_run(kthread_fn, NULL, + DRVNAME); + if (IS_ERR(kthread)) { + pr_err(BANNER "could not start sampling thread\n"); + enabled = 0; + return -ENOMEM; + } + + return 0; +} + +/** + * stop_kthread - Inform the hardware latency samping/detector kthread to stop + * + * This kicks the running hardware latency sampling/detector kernel thread and + * tells it to stop sampling now. Use this on unload and at system shutdown. + */ +static int stop_kthread(void) +{ + int ret; + + ret = kthread_stop(kthread); + + return ret; +} + +/** + * __reset_stats - Reset statistics for the hardware latency detector + * + * We use data to store various statistics and global state. We call this + * function in order to reset those when "enable" is toggled on or off, and + * also at initialization. Should be called with data.lock held. + */ +static void __reset_stats(void) +{ + data.count = 0; + data.max_sample = 0; + ring_buffer_reset(ring_buffer); /* flush out old sample entries */ +} + +/** + * init_stats - Setup global state statistics for the hardware latency detector + * + * We use data to store various statistics and global state. We also use + * a global ring buffer (ring_buffer) to keep raw samples of detected hardware + * induced system latencies. This function initializes these structures and + * allocates the global ring buffer also. + */ +static int init_stats(void) +{ + int ret = -ENOMEM; + + mutex_init(&data.lock); + init_waitqueue_head(&data.wq); + atomic_set(&data.sample_open, 0); + + ring_buffer = ring_buffer_alloc(buf_size, BUF_FLAGS); + + if (WARN(!ring_buffer, KERN_ERR BANNER + "failed to allocate ring buffer!\n")) + goto out; + + __reset_stats(); + data.threshold = threshold ?: DEFAULT_LAT_THRESHOLD; /* threshold us */ + data.sample_window = DEFAULT_SAMPLE_WINDOW; /* window us */ + data.sample_width = DEFAULT_SAMPLE_WIDTH; /* width us */ + + ret = 0; + +out: + return ret; + +} + +/* + * simple_data_read - Wrapper read function for global state debugfs entries + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The userspace provided buffer to read value into + * @cnt: The maximum number of bytes to read + * @ppos: The current "file" position + * @entry: The entry to read from + * + * This function provides a generic read implementation for the global state + * "data" structure debugfs filesystem entries. It would be nice to use + * simple_attr_read directly, but we need to make sure that the data.lock + * is held during the actual read. + */ +static ssize_t simple_data_read(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos, const u64 *entry) +{ + char buf[U64STR_SIZE]; + u64 val = 0; + int len = 0; + + memset(buf, 0, sizeof(buf)); + + if (!entry) + return -EFAULT; + + mutex_lock(&data.lock); + val = *entry; + mutex_unlock(&data.lock); + + len = snprintf(buf, sizeof(buf), "%llu\n", (unsigned long long)val); + + return simple_read_from_buffer(ubuf, cnt, ppos, buf, len); + +} + +/* + * simple_data_write - Wrapper write function for global state debugfs entries + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The userspace provided buffer to write value from + * @cnt: The maximum number of bytes to write + * @ppos: The current "file" position + * @entry: The entry to write to + * + * This function provides a generic write implementation for the global state + * "data" structure debugfs filesystem entries. It would be nice to use + * simple_attr_write directly, but we need to make sure that the data.lock + * is held during the actual write. + */ +static ssize_t simple_data_write(struct file *filp, const char __user *ubuf, + size_t cnt, loff_t *ppos, u64 *entry) +{ + char buf[U64STR_SIZE]; + int csize = min(cnt, sizeof(buf)); + u64 val = 0; + int err = 0; + + memset(buf, '\0', sizeof(buf)); + if (copy_from_user(buf, ubuf, csize)) + return -EFAULT; + + buf[U64STR_SIZE-1] = '\0'; /* just in case */ + err = kstrtoull(buf, 10, &val); + if (err) + return -EINVAL; + + mutex_lock(&data.lock); + *entry = val; + mutex_unlock(&data.lock); + + return csize; +} + +/** + * debug_count_fopen - Open function for "count" debugfs entry + * @inode: The in-kernel inode representation of the debugfs "file" + * @filp: The active open file structure for the debugfs "file" + * + * This function provides an open implementation for the "count" debugfs + * interface to the hardware latency detector. + */ +static int debug_count_fopen(struct inode *inode, struct file *filp) +{ + return 0; +} + +/** + * debug_count_fread - Read function for "count" debugfs entry + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The userspace provided buffer to read value into + * @cnt: The maximum number of bytes to read + * @ppos: The current "file" position + * + * This function provides a read implementation for the "count" debugfs + * interface to the hardware latency detector. Can be used to read the + * number of latency readings exceeding the configured threshold since + * the detector was last reset (e.g. by writing a zero into "count"). + */ +static ssize_t debug_count_fread(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + return simple_data_read(filp, ubuf, cnt, ppos, &data.count); +} + +/** + * debug_count_fwrite - Write function for "count" debugfs entry + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The user buffer that contains the value to write + * @cnt: The maximum number of bytes to write to "file" + * @ppos: The current position in the debugfs "file" + * + * This function provides a write implementation for the "count" debugfs + * interface to the hardware latency detector. Can be used to write a + * desired value, especially to zero the total count. + */ +static ssize_t debug_count_fwrite(struct file *filp, + const char __user *ubuf, + size_t cnt, + loff_t *ppos) +{ + return simple_data_write(filp, ubuf, cnt, ppos, &data.count); +} + +/** + * debug_enable_fopen - Dummy open function for "enable" debugfs interface + * @inode: The in-kernel inode representation of the debugfs "file" + * @filp: The active open file structure for the debugfs "file" + * + * This function provides an open implementation for the "enable" debugfs + * interface to the hardware latency detector. + */ +static int debug_enable_fopen(struct inode *inode, struct file *filp) +{ + return 0; +} + +/** + * debug_enable_fread - Read function for "enable" debugfs interface + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The userspace provided buffer to read value into + * @cnt: The maximum number of bytes to read + * @ppos: The current "file" position + * + * This function provides a read implementation for the "enable" debugfs + * interface to the hardware latency detector. Can be used to determine + * whether the detector is currently enabled ("0\n" or "1\n" returned). + */ +static ssize_t debug_enable_fread(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + char buf[4]; + + if ((cnt < sizeof(buf)) || (*ppos)) + return 0; + + buf[0] = enabled ? '1' : '0'; + buf[1] = '\n'; + buf[2] = '\0'; + if (copy_to_user(ubuf, buf, strlen(buf))) + return -EFAULT; + return *ppos = strlen(buf); +} + +/** + * debug_enable_fwrite - Write function for "enable" debugfs interface + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The user buffer that contains the value to write + * @cnt: The maximum number of bytes to write to "file" + * @ppos: The current position in the debugfs "file" + * + * This function provides a write implementation for the "enable" debugfs + * interface to the hardware latency detector. Can be used to enable or + * disable the detector, which will have the side-effect of possibly + * also resetting the global stats and kicking off the measuring + * kthread (on an enable) or the converse (upon a disable). + */ +static ssize_t debug_enable_fwrite(struct file *filp, + const char __user *ubuf, + size_t cnt, + loff_t *ppos) +{ + char buf[4]; + int csize = min(cnt, sizeof(buf)); + long val = 0; + int err = 0; + + memset(buf, '\0', sizeof(buf)); + if (copy_from_user(buf, ubuf, csize)) + return -EFAULT; + + buf[sizeof(buf)-1] = '\0'; /* just in case */ + err = kstrtoul(buf, 10, &val); + if (0 != err) + return -EINVAL; + + if (val) { + if (enabled) + goto unlock; + enabled = 1; + __reset_stats(); + if (start_kthread()) + return -EFAULT; + } else { + if (!enabled) + goto unlock; + enabled = 0; + err = stop_kthread(); + if (err) { + pr_err(BANNER "cannot stop kthread\n"); + return -EFAULT; + } + wake_up(&data.wq); /* reader(s) should return */ + } +unlock: + return csize; +} + +/** + * debug_max_fopen - Open function for "max" debugfs entry + * @inode: The in-kernel inode representation of the debugfs "file" + * @filp: The active open file structure for the debugfs "file" + * + * This function provides an open implementation for the "max" debugfs + * interface to the hardware latency detector. + */ +static int debug_max_fopen(struct inode *inode, struct file *filp) +{ + return 0; +} + +/** + * debug_max_fread - Read function for "max" debugfs entry + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The userspace provided buffer to read value into + * @cnt: The maximum number of bytes to read + * @ppos: The current "file" position + * + * This function provides a read implementation for the "max" debugfs + * interface to the hardware latency detector. Can be used to determine + * the maximum latency value observed since it was last reset. + */ +static ssize_t debug_max_fread(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + return simple_data_read(filp, ubuf, cnt, ppos, &data.max_sample); +} + +/** + * debug_max_fwrite - Write function for "max" debugfs entry + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The user buffer that contains the value to write + * @cnt: The maximum number of bytes to write to "file" + * @ppos: The current position in the debugfs "file" + * + * This function provides a write implementation for the "max" debugfs + * interface to the hardware latency detector. Can be used to reset the + * maximum or set it to some other desired value - if, then, subsequent + * measurements exceed this value, the maximum will be updated. + */ +static ssize_t debug_max_fwrite(struct file *filp, + const char __user *ubuf, + size_t cnt, + loff_t *ppos) +{ + return simple_data_write(filp, ubuf, cnt, ppos, &data.max_sample); +} + + +/** + * debug_sample_fopen - An open function for "sample" debugfs interface + * @inode: The in-kernel inode representation of this debugfs "file" + * @filp: The active open file structure for the debugfs "file" + * + * This function handles opening the "sample" file within the hardware + * latency detector debugfs directory interface. This file is used to read + * raw samples from the global ring_buffer and allows the user to see a + * running latency history. Can be opened blocking or non-blocking, + * affecting whether it behaves as a buffer read pipe, or does not. + * Implements simple locking to prevent multiple simultaneous use. + */ +static int debug_sample_fopen(struct inode *inode, struct file *filp) +{ + if (!atomic_add_unless(&data.sample_open, 1, 1)) + return -EBUSY; + else + return 0; +} + +/** + * debug_sample_fread - A read function for "sample" debugfs interface + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The user buffer that will contain the samples read + * @cnt: The maximum bytes to read from the debugfs "file" + * @ppos: The current position in the debugfs "file" + * + * This function handles reading from the "sample" file within the hardware + * latency detector debugfs directory interface. This file is used to read + * raw samples from the global ring_buffer and allows the user to see a + * running latency history. By default this will block pending a new + * value written into the sample buffer, unless there are already a + * number of value(s) waiting in the buffer, or the sample file was + * previously opened in a non-blocking mode of operation. + */ +static ssize_t debug_sample_fread(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + int len = 0; + char buf[64]; + struct sample *sample = NULL; + + if (!enabled) + return 0; + + sample = kzalloc(sizeof(struct sample), GFP_KERNEL); + if (!sample) + return -ENOMEM; + + while (!buffer_get_sample(sample)) { + + DEFINE_WAIT(wait); + + if (filp->f_flags & O_NONBLOCK) { + len = -EAGAIN; + goto out; + } + + prepare_to_wait(&data.wq, &wait, TASK_INTERRUPTIBLE); + schedule(); + finish_wait(&data.wq, &wait); + + if (signal_pending(current)) { + len = -EINTR; + goto out; + } + + if (!enabled) { /* enable was toggled */ + len = 0; + goto out; + } + } + + len = snprintf(buf, sizeof(buf), "%010lu.%010lu\t%llu\t%llu\n", + sample->timestamp.tv_sec, + sample->timestamp.tv_nsec, + sample->duration, + sample->outer_duration); + + + /* handling partial reads is more trouble than it's worth */ + if (len > cnt) + goto out; + + if (copy_to_user(ubuf, buf, len)) + len = -EFAULT; + +out: + kfree(sample); + return len; +} + +/** + * debug_sample_release - Release function for "sample" debugfs interface + * @inode: The in-kernel inode represenation of the debugfs "file" + * @filp: The active open file structure for the debugfs "file" + * + * This function completes the close of the debugfs interface "sample" file. + * Frees the sample_open "lock" so that other users may open the interface. + */ +static int debug_sample_release(struct inode *inode, struct file *filp) +{ + atomic_dec(&data.sample_open); + + return 0; +} + +/** + * debug_threshold_fopen - Open function for "threshold" debugfs entry + * @inode: The in-kernel inode representation of the debugfs "file" + * @filp: The active open file structure for the debugfs "file" + * + * This function provides an open implementation for the "threshold" debugfs + * interface to the hardware latency detector. + */ +static int debug_threshold_fopen(struct inode *inode, struct file *filp) +{ + return 0; +} + +/** + * debug_threshold_fread - Read function for "threshold" debugfs entry + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The userspace provided buffer to read value into + * @cnt: The maximum number of bytes to read + * @ppos: The current "file" position + * + * This function provides a read implementation for the "threshold" debugfs + * interface to the hardware latency detector. It can be used to determine + * the current threshold level at which a latency will be recorded in the + * global ring buffer, typically on the order of 10us. + */ +static ssize_t debug_threshold_fread(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + return simple_data_read(filp, ubuf, cnt, ppos, &data.threshold); +} + +/** + * debug_threshold_fwrite - Write function for "threshold" debugfs entry + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The user buffer that contains the value to write + * @cnt: The maximum number of bytes to write to "file" + * @ppos: The current position in the debugfs "file" + * + * This function provides a write implementation for the "threshold" debugfs + * interface to the hardware latency detector. It can be used to configure + * the threshold level at which any subsequently detected latencies will + * be recorded into the global ring buffer. + */ +static ssize_t debug_threshold_fwrite(struct file *filp, + const char __user *ubuf, + size_t cnt, + loff_t *ppos) +{ + int ret; + + ret = simple_data_write(filp, ubuf, cnt, ppos, &data.threshold); + + if (enabled) + wake_up_process(kthread); + + return ret; +} + +/** + * debug_width_fopen - Open function for "width" debugfs entry + * @inode: The in-kernel inode representation of the debugfs "file" + * @filp: The active open file structure for the debugfs "file" + * + * This function provides an open implementation for the "width" debugfs + * interface to the hardware latency detector. + */ +static int debug_width_fopen(struct inode *inode, struct file *filp) +{ + return 0; +} + +/** + * debug_width_fread - Read function for "width" debugfs entry + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The userspace provided buffer to read value into + * @cnt: The maximum number of bytes to read + * @ppos: The current "file" position + * + * This function provides a read implementation for the "width" debugfs + * interface to the hardware latency detector. It can be used to determine + * for how many us of the total window us we will actively sample for any + * hardware-induced latecy periods. Obviously, it is not possible to + * sample constantly and have the system respond to a sample reader, or, + * worse, without having the system appear to have gone out to lunch. + */ +static ssize_t debug_width_fread(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + return simple_data_read(filp, ubuf, cnt, ppos, &data.sample_width); +} + +/** + * debug_width_fwrite - Write function for "width" debugfs entry + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The user buffer that contains the value to write + * @cnt: The maximum number of bytes to write to "file" + * @ppos: The current position in the debugfs "file" + * + * This function provides a write implementation for the "width" debugfs + * interface to the hardware latency detector. It can be used to configure + * for how many us of the total window us we will actively sample for any + * hardware-induced latency periods. Obviously, it is not possible to + * sample constantly and have the system respond to a sample reader, or, + * worse, without having the system appear to have gone out to lunch. It + * is enforced that width is less that the total window size. + */ +static ssize_t debug_width_fwrite(struct file *filp, + const char __user *ubuf, + size_t cnt, + loff_t *ppos) +{ + char buf[U64STR_SIZE]; + int csize = min(cnt, sizeof(buf)); + u64 val = 0; + int err = 0; + + memset(buf, '\0', sizeof(buf)); + if (copy_from_user(buf, ubuf, csize)) + return -EFAULT; + + buf[U64STR_SIZE-1] = '\0'; /* just in case */ + err = kstrtoull(buf, 10, &val); + if (0 != err) + return -EINVAL; + + mutex_lock(&data.lock); + if (val < data.sample_window) + data.sample_width = val; + else { + mutex_unlock(&data.lock); + return -EINVAL; + } + mutex_unlock(&data.lock); + + if (enabled) + wake_up_process(kthread); + + return csize; +} + +/** + * debug_window_fopen - Open function for "window" debugfs entry + * @inode: The in-kernel inode representation of the debugfs "file" + * @filp: The active open file structure for the debugfs "file" + * + * This function provides an open implementation for the "window" debugfs + * interface to the hardware latency detector. The window is the total time + * in us that will be considered one sample period. Conceptually, windows + * occur back-to-back and contain a sample width period during which + * actual sampling occurs. + */ +static int debug_window_fopen(struct inode *inode, struct file *filp) +{ + return 0; +} + +/** + * debug_window_fread - Read function for "window" debugfs entry + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The userspace provided buffer to read value into + * @cnt: The maximum number of bytes to read + * @ppos: The current "file" position + * + * This function provides a read implementation for the "window" debugfs + * interface to the hardware latency detector. The window is the total time + * in us that will be considered one sample period. Conceptually, windows + * occur back-to-back and contain a sample width period during which + * actual sampling occurs. Can be used to read the total window size. + */ +static ssize_t debug_window_fread(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + return simple_data_read(filp, ubuf, cnt, ppos, &data.sample_window); +} + +/** + * debug_window_fwrite - Write function for "window" debugfs entry + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The user buffer that contains the value to write + * @cnt: The maximum number of bytes to write to "file" + * @ppos: The current position in the debugfs "file" + * + * This function provides a write implementation for the "window" debufds + * interface to the hardware latency detetector. The window is the total time + * in us that will be considered one sample period. Conceptually, windows + * occur back-to-back and contain a sample width period during which + * actual sampling occurs. Can be used to write a new total window size. It + * is enfoced that any value written must be greater than the sample width + * size, or an error results. + */ +static ssize_t debug_window_fwrite(struct file *filp, + const char __user *ubuf, + size_t cnt, + loff_t *ppos) +{ + char buf[U64STR_SIZE]; + int csize = min(cnt, sizeof(buf)); + u64 val = 0; + int err = 0; + + memset(buf, '\0', sizeof(buf)); + if (copy_from_user(buf, ubuf, csize)) + return -EFAULT; + + buf[U64STR_SIZE-1] = '\0'; /* just in case */ + err = kstrtoull(buf, 10, &val); + if (0 != err) + return -EINVAL; + + mutex_lock(&data.lock); + if (data.sample_width < val) + data.sample_window = val; + else { + mutex_unlock(&data.lock); + return -EINVAL; + } + mutex_unlock(&data.lock); + + return csize; +} + +/* + * Function pointers for the "count" debugfs file operations + */ +static const struct file_operations count_fops = { + .open = debug_count_fopen, + .read = debug_count_fread, + .write = debug_count_fwrite, + .owner = THIS_MODULE, +}; + +/* + * Function pointers for the "enable" debugfs file operations + */ +static const struct file_operations enable_fops = { + .open = debug_enable_fopen, + .read = debug_enable_fread, + .write = debug_enable_fwrite, + .owner = THIS_MODULE, +}; + +/* + * Function pointers for the "max" debugfs file operations + */ +static const struct file_operations max_fops = { + .open = debug_max_fopen, + .read = debug_max_fread, + .write = debug_max_fwrite, + .owner = THIS_MODULE, +}; + +/* + * Function pointers for the "sample" debugfs file operations + */ +static const struct file_operations sample_fops = { + .open = debug_sample_fopen, + .read = debug_sample_fread, + .release = debug_sample_release, + .owner = THIS_MODULE, +}; + +/* + * Function pointers for the "threshold" debugfs file operations + */ +static const struct file_operations threshold_fops = { + .open = debug_threshold_fopen, + .read = debug_threshold_fread, + .write = debug_threshold_fwrite, + .owner = THIS_MODULE, +}; + +/* + * Function pointers for the "width" debugfs file operations + */ +static const struct file_operations width_fops = { + .open = debug_width_fopen, + .read = debug_width_fread, + .write = debug_width_fwrite, + .owner = THIS_MODULE, +}; + +/* + * Function pointers for the "window" debugfs file operations + */ +static const struct file_operations window_fops = { + .open = debug_window_fopen, + .read = debug_window_fread, + .write = debug_window_fwrite, + .owner = THIS_MODULE, +}; + +/** + * init_debugfs - A function to initialize the debugfs interface files + * + * This function creates entries in debugfs for "hwlat_detector", including + * files to read values from the detector, current samples, and the + * maximum sample that has been captured since the hardware latency + * dectector was started. + */ +static int init_debugfs(void) +{ + int ret = -ENOMEM; + + debug_dir = debugfs_create_dir(DRVNAME, NULL); + if (!debug_dir) + goto err_debug_dir; + + debug_sample = debugfs_create_file("sample", 0444, + debug_dir, NULL, + &sample_fops); + if (!debug_sample) + goto err_sample; + + debug_count = debugfs_create_file("count", 0444, + debug_dir, NULL, + &count_fops); + if (!debug_count) + goto err_count; + + debug_max = debugfs_create_file("max", 0444, + debug_dir, NULL, + &max_fops); + if (!debug_max) + goto err_max; + + debug_sample_window = debugfs_create_file("window", 0644, + debug_dir, NULL, + &window_fops); + if (!debug_sample_window) + goto err_window; + + debug_sample_width = debugfs_create_file("width", 0644, + debug_dir, NULL, + &width_fops); + if (!debug_sample_width) + goto err_width; + + debug_threshold = debugfs_create_file("threshold", 0644, + debug_dir, NULL, + &threshold_fops); + if (!debug_threshold) + goto err_threshold; + + debug_enable = debugfs_create_file("enable", 0644, + debug_dir, &enabled, + &enable_fops); + if (!debug_enable) + goto err_enable; + + else { + ret = 0; + goto out; + } + +err_enable: + debugfs_remove(debug_threshold); +err_threshold: + debugfs_remove(debug_sample_width); +err_width: + debugfs_remove(debug_sample_window); +err_window: + debugfs_remove(debug_max); +err_max: + debugfs_remove(debug_count); +err_count: + debugfs_remove(debug_sample); +err_sample: + debugfs_remove(debug_dir); +err_debug_dir: +out: + return ret; +} + +/** + * free_debugfs - A function to cleanup the debugfs file interface + */ +static void free_debugfs(void) +{ + /* could also use a debugfs_remove_recursive */ + debugfs_remove(debug_enable); + debugfs_remove(debug_threshold); + debugfs_remove(debug_sample_width); + debugfs_remove(debug_sample_window); + debugfs_remove(debug_max); + debugfs_remove(debug_count); + debugfs_remove(debug_sample); + debugfs_remove(debug_dir); +} + +/** + * detector_init - Standard module initialization code + */ +static int detector_init(void) +{ + int ret = -ENOMEM; + + pr_info(BANNER "version %s\n", VERSION); + + ret = init_stats(); + if (0 != ret) + goto out; + + ret = init_debugfs(); + if (0 != ret) + goto err_stats; + + if (enabled) + ret = start_kthread(); + + goto out; + +err_stats: + ring_buffer_free(ring_buffer); +out: + return ret; + +} + +/** + * detector_exit - Standard module cleanup code + */ +static void detector_exit(void) +{ + int err; + + if (enabled) { + enabled = 0; + err = stop_kthread(); + if (err) + pr_err(BANNER "cannot stop kthread\n"); + } + + free_debugfs(); + ring_buffer_free(ring_buffer); /* free up the ring buffer */ + +} + +module_init(detector_init); +module_exit(detector_exit); Index: linux-3.12.19-rt30/drivers/mmc/host/mmci.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/mmc/host/mmci.c +++ linux-3.12.19-rt30/drivers/mmc/host/mmci.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1026 @ static irqreturn_t mmci_pio_irq(int irq, struct sg_mapping_iter *sg_miter = &host->sg_miter; struct variant_data *variant = host->variant; void __iomem *base = host->base; - unsigned long flags; u32 status; status = readl(base + MMCISTATUS); dev_dbg(mmc_dev(host->mmc), "irq1 (pio) %08x\n", status); - local_irq_save(flags); - do { unsigned int remain, len; char *buffer; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1071 @ static irqreturn_t mmci_pio_irq(int irq, sg_miter_stop(sg_miter); - local_irq_restore(flags); - /* * If we have less than the fifo 'half-full' threshold to transfer, * trigger a PIO interrupt as soon as any data is available. Index: linux-3.12.19-rt30/drivers/net/Kconfig =================================================================== --- linux-3.12.19-rt30.orig/drivers/net/Kconfig +++ linux-3.12.19-rt30/drivers/net/Kconfig @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:163 @ config VXLAN config NETCONSOLE tristate "Network console logging support" + depends on !PREEMPT_RT_FULL ---help--- If you want to log kernel messages over the network, enable this. See <file:Documentation/networking/netconsole.txt> for details. Index: linux-3.12.19-rt30/drivers/net/ethernet/3com/3c59x.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/net/ethernet/3com/3c59x.c +++ linux-3.12.19-rt30/drivers/net/ethernet/3com/3c59x.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:845 @ static void poll_vortex(struct net_devic { struct vortex_private *vp = netdev_priv(dev); unsigned long flags; - local_irq_save(flags); + local_irq_save_nort(flags); (vp->full_bus_master_rx ? boomerang_interrupt:vortex_interrupt)(dev->irq,dev); - local_irq_restore(flags); + local_irq_restore_nort(flags); } #endif @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1920 @ static void vortex_tx_timeout(struct net * Block interrupts because vortex_interrupt does a bare spin_lock() */ unsigned long flags; - local_irq_save(flags); + local_irq_save_nort(flags); if (vp->full_bus_master_tx) boomerang_interrupt(dev->irq, dev); else vortex_interrupt(dev->irq, dev); - local_irq_restore(flags); + local_irq_restore_nort(flags); } } Index: linux-3.12.19-rt30/drivers/net/ethernet/atheros/atl1c/atl1c_main.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/net/ethernet/atheros/atl1c/atl1c_main.c +++ linux-3.12.19-rt30/drivers/net/ethernet/atheros/atl1c/atl1c_main.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2209 @ static netdev_tx_t atl1c_xmit_frame(stru } tpd_req = atl1c_cal_tpd_req(skb); - if (!spin_trylock_irqsave(&adapter->tx_lock, flags)) { - if (netif_msg_pktdata(adapter)) - dev_info(&adapter->pdev->dev, "tx locked\n"); - return NETDEV_TX_LOCKED; - } + spin_lock_irqsave(&adapter->tx_lock, flags); if (atl1c_tpd_avail(adapter, type) < tpd_req) { /* no enough descriptor, just stop queue */ Index: linux-3.12.19-rt30/drivers/net/ethernet/atheros/atl1e/atl1e_main.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/net/ethernet/atheros/atl1e/atl1e_main.c +++ linux-3.12.19-rt30/drivers/net/ethernet/atheros/atl1e/atl1e_main.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1841 @ static netdev_tx_t atl1e_xmit_frame(stru return NETDEV_TX_OK; } tpd_req = atl1e_cal_tdp_req(skb); - if (!spin_trylock_irqsave(&adapter->tx_lock, flags)) - return NETDEV_TX_LOCKED; + spin_lock_irqsave(&adapter->tx_lock, flags); if (atl1e_tpd_avail(adapter) < tpd_req) { /* no enough descriptor, just stop queue */ Index: linux-3.12.19-rt30/drivers/net/ethernet/chelsio/cxgb/sge.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/net/ethernet/chelsio/cxgb/sge.c +++ linux-3.12.19-rt30/drivers/net/ethernet/chelsio/cxgb/sge.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1668 @ static int t1_sge_tx(struct sk_buff *skb struct cmdQ *q = &sge->cmdQ[qid]; unsigned int credits, pidx, genbit, count, use_sched_skb = 0; - if (!spin_trylock(&q->lock)) - return NETDEV_TX_LOCKED; + spin_lock(&q->lock); reclaim_completed_tx(sge, q); Index: linux-3.12.19-rt30/drivers/net/ethernet/freescale/gianfar.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/net/ethernet/freescale/gianfar.c +++ linux-3.12.19-rt30/drivers/net/ethernet/freescale/gianfar.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:137 @ static int gfar_poll_sq(struct napi_stru static void gfar_netpoll(struct net_device *dev); #endif int gfar_clean_rx_ring(struct gfar_priv_rx_q *rx_queue, int rx_work_limit); -static void gfar_clean_tx_ring(struct gfar_priv_tx_q *tx_queue); static void gfar_process_frame(struct net_device *dev, struct sk_buff *skb, int amount_pull, struct napi_struct *napi); void gfar_halt(struct net_device *dev); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1303 @ static int gfar_suspend(struct device *d if (netif_running(ndev)) { - local_irq_save(flags); + local_irq_save_nort(flags); lock_tx_qs(priv); lock_rx_qs(priv); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1321 @ static int gfar_suspend(struct device *d unlock_rx_qs(priv); unlock_tx_qs(priv); - local_irq_restore(flags); + local_irq_restore_nort(flags); disable_napi(priv); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1363 @ static int gfar_resume(struct device *de /* Disable Magic Packet mode, in case something * else woke us up. */ - local_irq_save(flags); + local_irq_save_nort(flags); lock_tx_qs(priv); lock_rx_qs(priv); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1375 @ static int gfar_resume(struct device *de unlock_rx_qs(priv); unlock_tx_qs(priv); - local_irq_restore(flags); + local_irq_restore_nort(flags); netif_device_attach(ndev); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1703 @ void stop_gfar(struct net_device *dev) /* Lock it down */ - local_irq_save(flags); + local_irq_save_nort(flags); lock_tx_qs(priv); lock_rx_qs(priv); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1711 @ void stop_gfar(struct net_device *dev) unlock_rx_qs(priv); unlock_tx_qs(priv); - local_irq_restore(flags); + local_irq_restore_nort(flags); /* Free the IRQs */ if (priv->device_flags & FSL_GIANFAR_DEV_HAS_MULTI_INTR) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2389 @ void gfar_vlan_mode(struct net_device *d u32 tempval; regs = priv->gfargrp[0].regs; - local_irq_save(flags); + local_irq_save_nort(flags); lock_rx_qs(priv); if (features & NETIF_F_HW_VLAN_CTAG_TX) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2422 @ void gfar_vlan_mode(struct net_device *d gfar_change_mtu(dev, dev->mtu); unlock_rx_qs(priv); - local_irq_restore(flags); + local_irq_restore_nort(flags); } static int gfar_change_mtu(struct net_device *dev, int new_mtu) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2518 @ static void gfar_align_skb(struct sk_buf } /* Interrupt Handler for Transmit complete */ -static void gfar_clean_tx_ring(struct gfar_priv_tx_q *tx_queue) +static int gfar_clean_tx_ring(struct gfar_priv_tx_q *tx_queue) { struct net_device *dev = tx_queue->dev; struct netdev_queue *txq; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2618 @ static void gfar_clean_tx_ring(struct gf tx_queue->dirty_tx = bdp; netdev_tx_completed_queue(txq, howmany, bytes_sent); + return howmany; } static void gfar_schedule_cleanup(struct gfar_priv_grp *gfargrp) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2942 @ static int gfar_poll(struct napi_struct tx_queue = priv->tx_queue[i]; /* run Tx cleanup to completion */ if (tx_queue->tx_skbuff[tx_queue->skb_dirtytx]) { - gfar_clean_tx_ring(tx_queue); - has_tx_work = 1; + int ret; + + ret = gfar_clean_tx_ring(tx_queue); + if (ret) + has_tx_work++; } } + work_done += has_tx_work; for_each_set_bit(i, &gfargrp->rx_bit_map, priv->num_rx_queues) { /* skip queue if not active */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:3108 @ static void adjust_link(struct net_devic struct phy_device *phydev = priv->phydev; int new_state = 0; - local_irq_save(flags); + local_irq_save_nort(flags); lock_tx_qs(priv); if (phydev->link) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:3182 @ static void adjust_link(struct net_devic if (new_state && netif_msg_link(priv)) phy_print_status(phydev); unlock_tx_qs(priv); - local_irq_restore(flags); + local_irq_restore_nort(flags); } /* Update the hash table based on the current list of multicast @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:3388 @ static irqreturn_t gfar_error(int irq, v dev->stats.tx_dropped++; atomic64_inc(&priv->extra_stats.tx_underrun); - local_irq_save(flags); + local_irq_save_nort(flags); lock_tx_qs(priv); /* Reactivate the Tx Queues */ gfar_write(®s->tstat, gfargrp->tstat); unlock_tx_qs(priv); - local_irq_restore(flags); + local_irq_restore_nort(flags); } netif_dbg(priv, tx_err, dev, "Transmit Error\n"); } Index: linux-3.12.19-rt30/drivers/net/ethernet/freescale/gianfar_ethtool.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/net/ethernet/freescale/gianfar_ethtool.c +++ linux-3.12.19-rt30/drivers/net/ethernet/freescale/gianfar_ethtool.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:504 @ static int gfar_sringparam(struct net_de /* Halt TX and RX, and process the frames which * have already been received */ - local_irq_save(flags); + local_irq_save_nort(flags); lock_tx_qs(priv); lock_rx_qs(priv); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:512 @ static int gfar_sringparam(struct net_de unlock_rx_qs(priv); unlock_tx_qs(priv); - local_irq_restore(flags); + local_irq_restore_nort(flags); for (i = 0; i < priv->num_rx_queues; i++) gfar_clean_rx_ring(priv->rx_queue[i], @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:627 @ int gfar_set_features(struct net_device /* Halt TX and RX, and process the frames which * have already been received */ - local_irq_save(flags); + local_irq_save_nort(flags); lock_tx_qs(priv); lock_rx_qs(priv); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:635 @ int gfar_set_features(struct net_device unlock_tx_qs(priv); unlock_rx_qs(priv); - local_irq_restore(flags); + local_irq_restore_nort(flags); for (i = 0; i < priv->num_rx_queues; i++) gfar_clean_rx_ring(priv->rx_queue[i], Index: linux-3.12.19-rt30/drivers/net/ethernet/freescale/gianfar_sysfs.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/net/ethernet/freescale/gianfar_sysfs.c +++ linux-3.12.19-rt30/drivers/net/ethernet/freescale/gianfar_sysfs.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:71 @ static ssize_t gfar_set_bd_stash(struct return count; - local_irq_save(flags); + local_irq_save_nort(flags); lock_rx_qs(priv); /* Set the new stashing value */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:87 @ static ssize_t gfar_set_bd_stash(struct gfar_write(®s->attr, temp); unlock_rx_qs(priv); - local_irq_restore(flags); + local_irq_restore_nort(flags); return count; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:115 @ static ssize_t gfar_set_rx_stash_size(st if (!(priv->device_flags & FSL_GIANFAR_DEV_HAS_BUF_STASHING)) return count; - local_irq_save(flags); + local_irq_save_nort(flags); lock_rx_qs(priv); if (length > priv->rx_buffer_size) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:143 @ static ssize_t gfar_set_rx_stash_size(st out: unlock_rx_qs(priv); - local_irq_restore(flags); + local_irq_restore_nort(flags); return count; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:174 @ static ssize_t gfar_set_rx_stash_index(s if (!(priv->device_flags & FSL_GIANFAR_DEV_HAS_BUF_STASHING)) return count; - local_irq_save(flags); + local_irq_save_nort(flags); lock_rx_qs(priv); if (index > priv->rx_stash_size) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:192 @ static ssize_t gfar_set_rx_stash_index(s out: unlock_rx_qs(priv); - local_irq_restore(flags); + local_irq_restore_nort(flags); return count; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:222 @ static ssize_t gfar_set_fifo_threshold(s if (length > GFAR_MAX_FIFO_THRESHOLD) return count; - local_irq_save(flags); + local_irq_save_nort(flags); lock_tx_qs(priv); priv->fifo_threshold = length; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:233 @ static ssize_t gfar_set_fifo_threshold(s gfar_write(®s->fifo_tx_thr, temp); unlock_tx_qs(priv); - local_irq_restore(flags); + local_irq_restore_nort(flags); return count; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:262 @ static ssize_t gfar_set_fifo_starve(stru if (num > GFAR_MAX_FIFO_STARVE) return count; - local_irq_save(flags); + local_irq_save_nort(flags); lock_tx_qs(priv); priv->fifo_starve = num; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:273 @ static ssize_t gfar_set_fifo_starve(stru gfar_write(®s->fifo_tx_starve, temp); unlock_tx_qs(priv); - local_irq_restore(flags); + local_irq_restore_nort(flags); return count; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:303 @ static ssize_t gfar_set_fifo_starve_off( if (num > GFAR_MAX_FIFO_STARVE_OFF) return count; - local_irq_save(flags); + local_irq_save_nort(flags); lock_tx_qs(priv); priv->fifo_starve_off = num; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:314 @ static ssize_t gfar_set_fifo_starve_off( gfar_write(®s->fifo_tx_starve_shutoff, temp); unlock_tx_qs(priv); - local_irq_restore(flags); + local_irq_restore_nort(flags); return count; } Index: linux-3.12.19-rt30/drivers/net/ethernet/neterion/s2io.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/net/ethernet/neterion/s2io.c +++ linux-3.12.19-rt30/drivers/net/ethernet/neterion/s2io.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:4092 @ static netdev_tx_t s2io_xmit(struct sk_b [skb->priority & (MAX_TX_FIFOS - 1)]; fifo = &mac_control->fifos[queue]; - if (do_spin_lock) - spin_lock_irqsave(&fifo->tx_lock, flags); - else { - if (unlikely(!spin_trylock_irqsave(&fifo->tx_lock, flags))) - return NETDEV_TX_LOCKED; - } + spin_lock_irqsave(&fifo->tx_lock, flags); if (sp->config.multiq) { if (__netif_subqueue_stopped(dev, fifo->fifo_no)) { Index: linux-3.12.19-rt30/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c +++ linux-3.12.19-rt30/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2151 @ static int pch_gbe_xmit_frame(struct sk_ struct pch_gbe_tx_ring *tx_ring = adapter->tx_ring; unsigned long flags; - if (!spin_trylock_irqsave(&tx_ring->tx_lock, flags)) { - /* Collision - tell upper layer to requeue */ - return NETDEV_TX_LOCKED; - } + spin_lock_irqsave(&tx_ring->tx_lock, flags); + if (unlikely(!PCH_GBE_DESC_UNUSED(tx_ring))) { netif_stop_queue(netdev); spin_unlock_irqrestore(&tx_ring->tx_lock, flags); Index: linux-3.12.19-rt30/drivers/net/ethernet/realtek/8139too.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/net/ethernet/realtek/8139too.c +++ linux-3.12.19-rt30/drivers/net/ethernet/realtek/8139too.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2216 @ static void rtl8139_poll_controller(stru struct rtl8139_private *tp = netdev_priv(dev); const int irq = tp->pci_dev->irq; - disable_irq(irq); + disable_irq_nosync(irq); rtl8139_interrupt(irq, dev); enable_irq(irq); } Index: linux-3.12.19-rt30/drivers/net/ethernet/tehuti/tehuti.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/net/ethernet/tehuti/tehuti.c +++ linux-3.12.19-rt30/drivers/net/ethernet/tehuti/tehuti.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1632 @ static netdev_tx_t bdx_tx_transmit(struc unsigned long flags; ENTER; - local_irq_save(flags); - if (!spin_trylock(&priv->tx_lock)) { - local_irq_restore(flags); - DBG("%s[%s]: TX locked, returning NETDEV_TX_LOCKED\n", - BDX_DRV_NAME, ndev->name); - return NETDEV_TX_LOCKED; - } + + spin_lock_irqsave(&priv->tx_lock, flags); /* build tx descriptor */ BDX_ASSERT(f->m.wptr >= f->m.memsz); /* started with valid wptr */ Index: linux-3.12.19-rt30/drivers/net/rionet.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/net/rionet.c +++ linux-3.12.19-rt30/drivers/net/rionet.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:177 @ static int rionet_start_xmit(struct sk_b unsigned long flags; int add_num = 1; - local_irq_save(flags); - if (!spin_trylock(&rnet->tx_lock)) { - local_irq_restore(flags); - return NETDEV_TX_LOCKED; - } + spin_lock_irqsave(&rnet->tx_lock, flags); if (is_multicast_ether_addr(eth->h_dest)) add_num = nets[rnet->mport->id].nact; Index: linux-3.12.19-rt30/drivers/net/wireless/iwlwifi/pcie/trans.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/net/wireless/iwlwifi/pcie/trans.c +++ linux-3.12.19-rt30/drivers/net/wireless/iwlwifi/pcie/trans.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1403 @ static const struct iwl_trans_ops trans_ .set_bits_mask = iwl_trans_pcie_set_bits_mask, }; +#ifdef CONFIG_PREEMPT_RT_BASE +static irqreturn_t iwl_rt_irq_handler(int irq, void *dev_id) +{ + irqreturn_t ret; + + local_bh_disable(); + ret = iwl_pcie_isr_ict(irq, dev_id); + local_bh_enable(); + if (ret == IRQ_WAKE_THREAD) + ret = iwl_pcie_irq_handler(irq, dev_id); + return ret; +} +#endif + struct iwl_trans *iwl_trans_pcie_alloc(struct pci_dev *pdev, const struct pci_device_id *ent, const struct iwl_cfg *cfg) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1535 @ struct iwl_trans *iwl_trans_pcie_alloc(s if (iwl_pcie_alloc_ict(trans)) goto out_free_cmd_pool; +#ifdef CONFIG_PREEMPT_RT_BASE + err = request_threaded_irq(pdev->irq, NULL, iwl_rt_irq_handler, + IRQF_SHARED | IRQF_ONESHOT, DRV_NAME, trans); +#else err = request_threaded_irq(pdev->irq, iwl_pcie_isr_ict, iwl_pcie_irq_handler, IRQF_SHARED, DRV_NAME, trans); +#endif if (err) { IWL_ERR(trans, "Error allocating IRQ %d\n", pdev->irq); goto out_free_ict; Index: linux-3.12.19-rt30/drivers/net/wireless/orinoco/orinoco_usb.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/net/wireless/orinoco/orinoco_usb.c +++ linux-3.12.19-rt30/drivers/net/wireless/orinoco/orinoco_usb.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:717 @ static void ezusb_req_ctx_wait(struct ez while (!ctx->done.done && msecs--) udelay(1000); } else { - wait_event_interruptible(ctx->done.wait, + swait_event_interruptible(ctx->done.wait, ctx->done.done); } break; Index: linux-3.12.19-rt30/drivers/pci/access.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/pci/access.c +++ linux-3.12.19-rt30/drivers/pci/access.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:468 @ void pci_cfg_access_unlock(struct pci_de WARN_ON(!dev->block_cfg_access); dev->block_cfg_access = 0; - wake_up_all(&pci_cfg_wait); + wake_up_all_locked(&pci_cfg_wait); raw_spin_unlock_irqrestore(&pci_lock, flags); } EXPORT_SYMBOL_GPL(pci_cfg_access_unlock); Index: linux-3.12.19-rt30/drivers/scsi/fcoe/fcoe.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/scsi/fcoe/fcoe.c +++ linux-3.12.19-rt30/drivers/scsi/fcoe/fcoe.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1288 @ static void fcoe_percpu_thread_destroy(u struct sk_buff *skb; #ifdef CONFIG_SMP struct fcoe_percpu_s *p0; - unsigned targ_cpu = get_cpu(); + unsigned targ_cpu = get_cpu_light(); #endif /* CONFIG_SMP */ FCOE_DBG("Destroying receive thread for CPU %d\n", cpu); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1344 @ static void fcoe_percpu_thread_destroy(u kfree_skb(skb); spin_unlock_bh(&p->fcoe_rx_list.lock); } - put_cpu(); + put_cpu_light(); #else /* * This a non-SMP scenario where the singular Rx thread is @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1562 @ err2: 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; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1764 @ static inline int fcoe_filter_frames(str 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; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1844 @ static void fcoe_recv_frame(struct sk_bu 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); } Index: linux-3.12.19-rt30/drivers/scsi/fcoe/fcoe_ctlr.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/scsi/fcoe/fcoe_ctlr.c +++ linux-3.12.19-rt30/drivers/scsi/fcoe/fcoe_ctlr.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:795 @ static unsigned long fcoe_ctlr_age_fcfs( 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; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:831 @ static unsigned long fcoe_ctlr_age_fcfs( sel_time = fcf->time; } } - put_cpu(); + put_cpu_light(); list_for_each_entry_safe(fcf, next, &del_list, list) { /* Removes fcf from current list */ Index: linux-3.12.19-rt30/drivers/scsi/libfc/fc_exch.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/scsi/libfc/fc_exch.c +++ linux-3.12.19-rt30/drivers/scsi/libfc/fc_exch.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:744 @ static struct fc_exch *fc_exch_em_alloc( } 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) { Index: linux-3.12.19-rt30/drivers/scsi/qla2xxx/qla_inline.h =================================================================== --- linux-3.12.19-rt30.orig/drivers/scsi/qla2xxx/qla_inline.h +++ linux-3.12.19-rt30/drivers/scsi/qla2xxx/qla_inline.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:61 @ qla2x00_poll(struct rsp_que *rsp) { unsigned long flags; struct qla_hw_data *ha = rsp->hw; - local_irq_save(flags); + local_irq_save_nort(flags); if (IS_P3P_TYPE(ha)) qla82xx_poll(0, rsp); else ha->isp_ops->intr_handler(0, rsp); - local_irq_restore(flags); + local_irq_restore_nort(flags); } static inline uint8_t * Index: linux-3.12.19-rt30/drivers/tty/serial/8250/8250_core.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/tty/serial/8250/8250_core.c +++ linux-3.12.19-rt30/drivers/tty/serial/8250/8250_core.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:41 @ #include <linux/nmi.h> #include <linux/mutex.h> #include <linux/slab.h> +#include <linux/kdb.h> #ifdef CONFIG_SPARC #include <linux/sunserialcore.h> #endif @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:84 @ static unsigned int skip_txen_test; /* f #define DEBUG_INTR(fmt...) do { } while (0) #endif -#define PASS_LIMIT 512 +/* + * On -rt we can have a more delays, and legitimately + * so - so don't drop work spuriously and spam the + * syslog: + */ +#ifdef CONFIG_PREEMPT_RT_FULL +# define PASS_LIMIT 1000000 +#else +# define PASS_LIMIT 512 +#endif #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2877 @ serial8250_console_write(struct console touch_nmi_watchdog(); - local_irq_save(flags); - if (port->sysrq) { - /* serial8250_handle_irq() already took the lock */ - locked = 0; - } else if (oops_in_progress) { - locked = spin_trylock(&port->lock); - } else - spin_lock(&port->lock); + if (port->sysrq || oops_in_progress || in_kdb_printk()) + locked = spin_trylock_irqsave(&port->lock, flags); + else + spin_lock_irqsave(&port->lock, flags); /* * First save the IER then disable the interrupts @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2912 @ serial8250_console_write(struct console serial8250_modem_status(up); if (locked) - spin_unlock(&port->lock); - local_irq_restore(flags); + spin_unlock_irqrestore(&port->lock, flags); } static int __init serial8250_console_setup(struct console *co, char *options) Index: linux-3.12.19-rt30/drivers/tty/serial/amba-pl011.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/tty/serial/amba-pl011.c +++ linux-3.12.19-rt30/drivers/tty/serial/amba-pl011.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1919 @ pl011_console_write(struct console *co, 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 @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1953 @ pl011_console_write(struct console *co, writew(old_cr, uap->port.membase + UART011_CR); if (locked) - spin_unlock(&uap->port.lock); - local_irq_restore(flags); + spin_unlock_irqrestore(&uap->port.lock, flags); clk_disable(uap->clk); } Index: linux-3.12.19-rt30/drivers/tty/serial/omap-serial.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/tty/serial/omap-serial.c +++ linux-3.12.19-rt30/drivers/tty/serial/omap-serial.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1235 @ serial_omap_console_write(struct console 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 @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1267 @ serial_omap_console_write(struct console 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 Index: linux-3.12.19-rt30/drivers/tty/serial/sunhv.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/tty/serial/sunhv.c +++ linux-3.12.19-rt30/drivers/tty/serial/sunhv.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:436 @ static void sunhv_console_write_paged(st unsigned long flags; int locked = 1; - local_irq_save(flags); - if (port->sysrq) { - locked = 0; - } else if (oops_in_progress) { - locked = spin_trylock(&port->lock); - } else - spin_lock(&port->lock); + if (port->sysrq || oops_in_progress) + locked = spin_trylock_irqsave(&port->lock, flags); + else + spin_lock_irqsave(&port->lock, flags); while (n > 0) { unsigned long ra = __pa(con_write_page); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:470 @ static void sunhv_console_write_paged(st } if (locked) - spin_unlock(&port->lock); - local_irq_restore(flags); + spin_unlock_irqrestore(&port->lock, flags); } static inline void sunhv_console_putchar(struct uart_port *port, char c) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:491 @ static void sunhv_console_write_bychar(s unsigned long flags; int i, locked = 1; - local_irq_save(flags); + if (port->sysrq || oops_in_progress) + locked = spin_trylock_irqsave(&port->lock, flags); + else + spin_lock_irqsave(&port->lock, flags); if (port->sysrq) { locked = 0; } else if (oops_in_progress) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:509 @ static void sunhv_console_write_bychar(s } if (locked) - spin_unlock(&port->lock); - local_irq_restore(flags); + spin_unlock_irqrestore(&port->lock, flags); } static struct console sunhv_console = { Index: linux-3.12.19-rt30/drivers/tty/serial/sunsab.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/tty/serial/sunsab.c +++ linux-3.12.19-rt30/drivers/tty/serial/sunsab.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:856 @ static void sunsab_console_write(struct unsigned long flags; int locked = 1; - local_irq_save(flags); - if (up->port.sysrq) { - locked = 0; - } else if (oops_in_progress) { - locked = spin_trylock(&up->port.lock); - } else - spin_lock(&up->port.lock); + if (up->port.sysrq || oops_in_progress) + locked = spin_trylock_irqsave(&up->port.lock, flags); + else + spin_lock_irqsave(&up->port.lock, flags); uart_console_write(&up->port, s, n, sunsab_console_putchar); sunsab_tec_wait(up); if (locked) - spin_unlock(&up->port.lock); - local_irq_restore(flags); + spin_unlock_irqrestore(&up->port.lock, flags); } static int sunsab_console_setup(struct console *con, char *options) Index: linux-3.12.19-rt30/drivers/tty/serial/sunsu.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/tty/serial/sunsu.c +++ linux-3.12.19-rt30/drivers/tty/serial/sunsu.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1298 @ static void sunsu_console_write(struct c unsigned int ier; int locked = 1; - local_irq_save(flags); - if (up->port.sysrq) { - locked = 0; - } else if (oops_in_progress) { - locked = spin_trylock(&up->port.lock); - } else - spin_lock(&up->port.lock); + if (up->port.sysrq || oops_in_progress) + locked = spin_trylock_irqsave(&up->port.lock, flags); + else + spin_lock_irqsave(&up->port.lock, flags); /* * First save the UER then disable the interrupts @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1319 @ static void sunsu_console_write(struct c serial_out(up, UART_IER, ier); if (locked) - spin_unlock(&up->port.lock); - local_irq_restore(flags); + spin_unlock_irqrestore(&up->port.lock, flags); } /* Index: linux-3.12.19-rt30/drivers/tty/serial/sunzilog.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/tty/serial/sunzilog.c +++ linux-3.12.19-rt30/drivers/tty/serial/sunzilog.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1198 @ sunzilog_console_write(struct console *c unsigned long flags; int locked = 1; - local_irq_save(flags); - if (up->port.sysrq) { - locked = 0; - } else if (oops_in_progress) { - locked = spin_trylock(&up->port.lock); - } else - spin_lock(&up->port.lock); + if (up->port.sysrq || oops_in_progress) + locked = spin_trylock_irqsave(&up->port.lock, flags); + else + spin_lock_irqsave(&up->port.lock, flags); uart_console_write(&up->port, s, count, sunzilog_putchar); udelay(2); if (locked) - spin_unlock(&up->port.lock); - local_irq_restore(flags); + spin_unlock_irqrestore(&up->port.lock, flags); } static int __init sunzilog_console_setup(struct console *con, char *options) Index: linux-3.12.19-rt30/drivers/usb/core/hcd.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/usb/core/hcd.c +++ linux-3.12.19-rt30/drivers/usb/core/hcd.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1680 @ static void __usb_hcd_giveback_urb(struc * and no one may trigger the above deadlock situation when * running complete() in tasklet. */ - local_irq_save(flags); + local_irq_save_nort(flags); urb->complete(urb); - local_irq_restore(flags); + local_irq_restore_nort(flags); atomic_dec(&urb->use_count); if (unlikely(atomic_read(&urb->reject))) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2334 @ irqreturn_t usb_hcd_irq (int irq, void * * when the first handler doesn't use it. So let's just * assume it's never used. */ - local_irq_save(flags); + local_irq_save_nort(flags); if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd))) rc = IRQ_NONE; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2343 @ irqreturn_t usb_hcd_irq (int irq, void * else rc = IRQ_HANDLED; - local_irq_restore(flags); + local_irq_restore_nort(flags); return rc; } EXPORT_SYMBOL_GPL(usb_hcd_irq); Index: linux-3.12.19-rt30/drivers/usb/gadget/f_fs.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/usb/gadget/f_fs.c +++ linux-3.12.19-rt30/drivers/usb/gadget/f_fs.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1285 @ static void ffs_data_put(struct ffs_data pr_info("%s(): freeing\n", __func__); ffs_data_clear(ffs); BUG_ON(waitqueue_active(&ffs->ev.waitq) || - waitqueue_active(&ffs->ep0req_completion.wait)); + swaitqueue_active(&ffs->ep0req_completion.wait)); kfree(ffs->dev_name); kfree(ffs); } Index: linux-3.12.19-rt30/drivers/usb/gadget/inode.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/usb/gadget/inode.c +++ linux-3.12.19-rt30/drivers/usb/gadget/inode.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:343 @ ep_io (struct ep_data *epdata, void *buf spin_unlock_irq (&epdata->dev->lock); if (likely (value == 0)) { - value = wait_event_interruptible (done.wait, done.done); + value = swait_event_interruptible (done.wait, done.done); if (value != 0) { spin_lock_irq (&epdata->dev->lock); if (likely (epdata->ep != NULL)) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:352 @ ep_io (struct ep_data *epdata, void *buf usb_ep_dequeue (epdata->ep, epdata->req); spin_unlock_irq (&epdata->dev->lock); - wait_event (done.wait, done.done); + swait_event (done.wait, done.done); if (epdata->status == -ECONNRESET) epdata->status = -EINTR; } else { Index: linux-3.12.19-rt30/drivers/usb/host/ohci-hcd.c =================================================================== --- linux-3.12.19-rt30.orig/drivers/usb/host/ohci-hcd.c +++ linux-3.12.19-rt30/drivers/usb/host/ohci-hcd.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:877 @ static irqreturn_t ohci_irq (struct usb_ } if (ints & OHCI_INTR_WDH) { - spin_lock (&ohci->lock); - dl_done_list (ohci); - spin_unlock (&ohci->lock); + if (ohci->hcca->done_head == 0) { + ints &= ~OHCI_INTR_WDH; + } else { + spin_lock (&ohci->lock); + dl_done_list (ohci); + spin_unlock (&ohci->lock); + } } if (quirk_zfmicro(ohci) && (ints & OHCI_INTR_SF)) { Index: linux-3.12.19-rt30/fs/autofs4/autofs_i.h =================================================================== --- linux-3.12.19-rt30.orig/fs/autofs4/autofs_i.h +++ linux-3.12.19-rt30/fs/autofs4/autofs_i.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:37 @ #include <linux/sched.h> #include <linux/mount.h> #include <linux/namei.h> +#include <linux/delay.h> #include <asm/current.h> #include <asm/uaccess.h> Index: linux-3.12.19-rt30/fs/autofs4/expire.c =================================================================== --- linux-3.12.19-rt30.orig/fs/autofs4/expire.c +++ linux-3.12.19-rt30/fs/autofs4/expire.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:160 @ again: parent = p->d_parent; if (!spin_trylock(&parent->d_lock)) { spin_unlock(&p->d_lock); - cpu_relax(); + cpu_chill(); goto relock; } spin_unlock(&p->d_lock); Index: linux-3.12.19-rt30/fs/buffer.c =================================================================== --- linux-3.12.19-rt30.orig/fs/buffer.c +++ linux-3.12.19-rt30/fs/buffer.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:325 @ static void end_buffer_async_read(struct * decide that the page is now completely done. */ first = page_buffers(page); - local_irq_save(flags); - bit_spin_lock(BH_Uptodate_Lock, &first->b_state); + flags = bh_uptodate_lock_irqsave(first); clear_buffer_async_read(bh); unlock_buffer(bh); tmp = bh; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:338 @ static void end_buffer_async_read(struct } tmp = tmp->b_this_page; } while (tmp != bh); - bit_spin_unlock(BH_Uptodate_Lock, &first->b_state); - local_irq_restore(flags); + bh_uptodate_unlock_irqrestore(first, flags); /* * If none of the buffers had errors and they are all @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:350 @ static void end_buffer_async_read(struct return; still_busy: - bit_spin_unlock(BH_Uptodate_Lock, &first->b_state); - local_irq_restore(flags); - return; + bh_uptodate_unlock_irqrestore(first, flags); } /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:384 @ void end_buffer_async_write(struct buffe } first = page_buffers(page); - local_irq_save(flags); - bit_spin_lock(BH_Uptodate_Lock, &first->b_state); + flags = bh_uptodate_lock_irqsave(first); clear_buffer_async_write(bh); unlock_buffer(bh); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:396 @ void end_buffer_async_write(struct buffe } tmp = tmp->b_this_page; } - bit_spin_unlock(BH_Uptodate_Lock, &first->b_state); - local_irq_restore(flags); + bh_uptodate_unlock_irqrestore(first, flags); end_page_writeback(page); return; still_busy: - bit_spin_unlock(BH_Uptodate_Lock, &first->b_state); - local_irq_restore(flags); - return; + bh_uptodate_unlock_irqrestore(first, flags); } EXPORT_SYMBOL(end_buffer_async_write); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:3345 @ struct buffer_head *alloc_buffer_head(gf struct buffer_head *ret = kmem_cache_zalloc(bh_cachep, gfp_flags); if (ret) { INIT_LIST_HEAD(&ret->b_assoc_buffers); + buffer_head_init_locks(ret); preempt_disable(); __this_cpu_inc(bh_accounting.nr); recalc_bh_state(); Index: linux-3.12.19-rt30/fs/dcache.c =================================================================== --- linux-3.12.19-rt30.orig/fs/dcache.c +++ linux-3.12.19-rt30/fs/dcache.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:22 @ #include <linux/mm.h> #include <linux/fs.h> #include <linux/fsnotify.h> +#include <linux/delay.h> #include <linux/slab.h> #include <linux/init.h> #include <linux/hash.h> @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:555 @ dentry_kill(struct dentry *dentry, int u relock: if (unlock_on_failure) { spin_unlock(&dentry->d_lock); - cpu_relax(); + cpu_chill(); } return dentry; /* try again with same dentry */ } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2392 @ again: if (dentry->d_lockref.count == 1) { if (!spin_trylock(&inode->i_lock)) { spin_unlock(&dentry->d_lock); - cpu_relax(); + cpu_chill(); goto again; } dentry->d_flags &= ~DCACHE_CANT_MOUNT; Index: linux-3.12.19-rt30/fs/eventpoll.c =================================================================== --- linux-3.12.19-rt30.orig/fs/eventpoll.c +++ linux-3.12.19-rt30/fs/eventpoll.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:508 @ static int ep_poll_wakeup_proc(void *pri */ static void ep_poll_safewake(wait_queue_head_t *wq) { - int this_cpu = get_cpu(); + int this_cpu = get_cpu_light(); ep_call_nested(&poll_safewake_ncalls, EP_MAX_NESTS, ep_poll_wakeup_proc, NULL, wq, (void *) (long) this_cpu); - put_cpu(); + put_cpu_light(); } static void ep_remove_wait_queue(struct eppoll_entry *pwq) Index: linux-3.12.19-rt30/fs/exec.c =================================================================== --- linux-3.12.19-rt30.orig/fs/exec.c +++ linux-3.12.19-rt30/fs/exec.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:844 @ static int exec_mmap(struct mm_struct *m } } task_lock(tsk); + preempt_disable_rt(); active_mm = tsk->active_mm; tsk->mm = mm; tsk->active_mm = mm; activate_mm(active_mm, mm); tsk->mm->vmacache_seqnum = 0; vmacache_flush(tsk); + preempt_enable_rt(); task_unlock(tsk); arch_pick_mmap_layout(mm); if (old_mm) { Index: linux-3.12.19-rt30/fs/jbd/checkpoint.c =================================================================== --- linux-3.12.19-rt30.orig/fs/jbd/checkpoint.c +++ linux-3.12.19-rt30/fs/jbd/checkpoint.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:132 @ void __log_wait_for_space(journal_t *jou if (journal->j_flags & JFS_ABORT) return; spin_unlock(&journal->j_state_lock); + if (current->plug) + io_schedule(); mutex_lock(&journal->j_checkpoint_mutex); /* Index: linux-3.12.19-rt30/fs/jbd2/checkpoint.c =================================================================== --- linux-3.12.19-rt30.orig/fs/jbd2/checkpoint.c +++ linux-3.12.19-rt30/fs/jbd2/checkpoint.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:128 @ void __jbd2_log_wait_for_space(journal_t if (journal->j_flags & JBD2_ABORT) return; write_unlock(&journal->j_state_lock); + if (current->plug) + io_schedule(); mutex_lock(&journal->j_checkpoint_mutex); /* Index: linux-3.12.19-rt30/fs/namespace.c =================================================================== --- linux-3.12.19-rt30.orig/fs/namespace.c +++ linux-3.12.19-rt30/fs/namespace.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:26 @ #include <linux/uaccess.h> #include <linux/proc_ns.h> #include <linux/magic.h> +#include <linux/delay.h> #include "pnode.h" #include "internal.h" @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:319 @ int __mnt_want_write(struct vfsmount *m) * incremented count after it has set MNT_WRITE_HOLD. */ smp_mb(); - while (ACCESS_ONCE(mnt->mnt.mnt_flags) & MNT_WRITE_HOLD) - cpu_relax(); + while (ACCESS_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 Index: linux-3.12.19-rt30/fs/ntfs/aops.c =================================================================== --- linux-3.12.19-rt30.orig/fs/ntfs/aops.c +++ linux-3.12.19-rt30/fs/ntfs/aops.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:111 @ static void ntfs_end_buffer_async_read(s "0x%llx.", (unsigned long long)bh->b_blocknr); } first = page_buffers(page); - local_irq_save(flags); - bit_spin_lock(BH_Uptodate_Lock, &first->b_state); + flags = bh_uptodate_lock_irqsave(first); clear_buffer_async_read(bh); unlock_buffer(bh); tmp = bh; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:126 @ static void ntfs_end_buffer_async_read(s } tmp = tmp->b_this_page; } while (tmp != bh); - bit_spin_unlock(BH_Uptodate_Lock, &first->b_state); - local_irq_restore(flags); + bh_uptodate_unlock_irqrestore(first, flags); /* * If none of the buffers had errors then we can set the page uptodate, * but we first have to perform the post read mst fixups, if the @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:147 @ static void ntfs_end_buffer_async_read(s recs = PAGE_CACHE_SIZE / rec_size; /* Should have been verified before we got here... */ BUG_ON(!recs); - local_irq_save(flags); + local_irq_save_nort(flags); kaddr = kmap_atomic(page); for (i = 0; i < recs; i++) post_read_mst_fixup((NTFS_RECORD*)(kaddr + i * rec_size), rec_size); kunmap_atomic(kaddr); - local_irq_restore(flags); + local_irq_restore_nort(flags); flush_dcache_page(page); if (likely(page_uptodate && !PageError(page))) SetPageUptodate(page); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:161 @ static void ntfs_end_buffer_async_read(s unlock_page(page); return; still_busy: - bit_spin_unlock(BH_Uptodate_Lock, &first->b_state); - local_irq_restore(flags); - return; + bh_uptodate_unlock_irqrestore(first, flags); } /** Index: linux-3.12.19-rt30/fs/timerfd.c =================================================================== --- linux-3.12.19-rt30.orig/fs/timerfd.c +++ linux-3.12.19-rt30/fs/timerfd.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:383 @ static int do_timerfd_settime(int ufd, i break; } spin_unlock_irq(&ctx->wqh.lock); - cpu_relax(); + if (isalarm(ctx)) + hrtimer_wait_for_timer(&ctx->t.alarm.timer); + else + hrtimer_wait_for_timer(&ctx->t.tmr); } /* Index: linux-3.12.19-rt30/include/acpi/platform/aclinux.h =================================================================== --- linux-3.12.19-rt30.orig/include/acpi/platform/aclinux.h +++ linux-3.12.19-rt30/include/acpi/platform/aclinux.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:75 @ #define acpi_cache_t struct kmem_cache #define acpi_spinlock spinlock_t * +#define acpi_raw_spinlock raw_spinlock_t * #define acpi_cpu_flags unsigned long #else /* !__KERNEL__ */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:178 @ static inline void *acpi_os_acquire_obje lock ? AE_OK : AE_NO_MEMORY; \ }) +#define acpi_os_create_raw_lock(__handle) \ +({ \ + raw_spinlock_t *lock = ACPI_ALLOCATE(sizeof(*lock)); \ + \ + if (lock) { \ + *(__handle) = lock; \ + raw_spin_lock_init(*(__handle)); \ + } \ + lock ? AE_OK : AE_NO_MEMORY; \ +}) + +#define acpi_os_delete_raw_lock(__handle) kfree(__handle) + #endif /* __KERNEL__ */ #endif /* __ACLINUX_H__ */ Index: linux-3.12.19-rt30/include/asm-generic/bug.h =================================================================== --- linux-3.12.19-rt30.orig/include/asm-generic/bug.h +++ linux-3.12.19-rt30/include/asm-generic/bug.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:205 @ extern void warn_slowpath_null(const cha # define WARN_ON_SMP(x) ({0;}) #endif +#ifdef CONFIG_PREEMPT_RT_BASE +# define BUG_ON_RT(c) BUG_ON(c) +# define BUG_ON_NONRT(c) do { } while (0) +# define WARN_ON_RT(condition) WARN_ON(condition) +# define WARN_ON_NONRT(condition) do { } while (0) +# define WARN_ON_ONCE_NONRT(condition) do { } while (0) +#else +# define BUG_ON_RT(c) do { } while (0) +# define BUG_ON_NONRT(c) BUG_ON(c) +# define WARN_ON_RT(condition) do { } while (0) +# define WARN_ON_NONRT(condition) WARN_ON(condition) +# define WARN_ON_ONCE_NONRT(condition) WARN_ON_ONCE(condition) +#endif + #endif /* __ASSEMBLY__ */ #endif Index: linux-3.12.19-rt30/include/linux/buffer_head.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/buffer_head.h +++ linux-3.12.19-rt30/include/linux/buffer_head.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:78 @ struct buffer_head { struct address_space *b_assoc_map; /* mapping this buffer is associated with */ atomic_t b_count; /* users using this buffer_head */ +#ifdef CONFIG_PREEMPT_RT_BASE + spinlock_t b_uptodate_lock; +#if defined(CONFIG_JBD) || defined(CONFIG_JBD_MODULE) || \ + defined(CONFIG_JBD2) || defined(CONFIG_JBD2_MODULE) + spinlock_t b_state_lock; + spinlock_t b_journal_head_lock; +#endif +#endif }; +static inline unsigned long bh_uptodate_lock_irqsave(struct buffer_head *bh) +{ + unsigned long flags; + +#ifndef CONFIG_PREEMPT_RT_BASE + local_irq_save(flags); + bit_spin_lock(BH_Uptodate_Lock, &bh->b_state); +#else + spin_lock_irqsave(&bh->b_uptodate_lock, flags); +#endif + return flags; +} + +static inline void +bh_uptodate_unlock_irqrestore(struct buffer_head *bh, unsigned long flags) +{ +#ifndef CONFIG_PREEMPT_RT_BASE + bit_spin_unlock(BH_Uptodate_Lock, &bh->b_state); + local_irq_restore(flags); +#else + spin_unlock_irqrestore(&bh->b_uptodate_lock, flags); +#endif +} + +static inline void buffer_head_init_locks(struct buffer_head *bh) +{ +#ifdef CONFIG_PREEMPT_RT_BASE + spin_lock_init(&bh->b_uptodate_lock); +#if defined(CONFIG_JBD) || defined(CONFIG_JBD_MODULE) || \ + defined(CONFIG_JBD2) || defined(CONFIG_JBD2_MODULE) + spin_lock_init(&bh->b_state_lock); + spin_lock_init(&bh->b_journal_head_lock); +#endif +#endif +} + /* * macro tricks to expand the set_buffer_foo(), clear_buffer_foo() * and buffer_foo() functions. Index: linux-3.12.19-rt30/include/linux/completion.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/completion.h +++ linux-3.12.19-rt30/include/linux/completion.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:11 @ * See kernel/sched/core.c for details. */ -#include <linux/wait.h> +#include <linux/wait-simple.h> /* * struct completion - structure used to maintain state for a "completion" @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:27 @ */ struct completion { unsigned int done; - wait_queue_head_t wait; + struct swait_head wait; }; #define COMPLETION_INITIALIZER(work) \ - { 0, __WAIT_QUEUE_HEAD_INITIALIZER((work).wait) } + { 0, SWAIT_HEAD_INITIALIZER((work).wait) } #define COMPLETION_INITIALIZER_ONSTACK(work) \ ({ init_completion(&work); work; }) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:76 @ struct completion { static inline void init_completion(struct completion *x) { x->done = 0; - init_waitqueue_head(&x->wait); + init_swait_head(&x->wait); } extern void wait_for_completion(struct completion *); Index: linux-3.12.19-rt30/include/linux/cpu.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/cpu.h +++ linux-3.12.19-rt30/include/linux/cpu.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:182 @ extern void get_online_cpus(void); extern void put_online_cpus(void); extern void cpu_hotplug_disable(void); extern void cpu_hotplug_enable(void); +extern void pin_current_cpu(void); +extern void unpin_current_cpu(void); #define hotcpu_notifier(fn, pri) cpu_notifier(fn, pri) #define register_hotcpu_notifier(nb) register_cpu_notifier(nb) #define unregister_hotcpu_notifier(nb) unregister_cpu_notifier(nb) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:211 @ static inline void cpu_hotplug_done(void #define put_online_cpus() do { } while (0) #define cpu_hotplug_disable() do { } while (0) #define cpu_hotplug_enable() do { } while (0) +static inline void pin_current_cpu(void) { } +static inline void unpin_current_cpu(void) { } #define hotcpu_notifier(fn, pri) do { (void)(fn); } while (0) /* These aren't inline functions due to a GCC bug. */ #define register_hotcpu_notifier(nb) ({ (void)(nb); 0; }) Index: linux-3.12.19-rt30/include/linux/delay.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/delay.h +++ linux-3.12.19-rt30/include/linux/delay.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:55 @ static inline void ssleep(unsigned int s msleep(seconds * 1000); } +#ifdef CONFIG_PREEMPT_RT_FULL +extern void cpu_chill(void); +#else +# define cpu_chill() cpu_relax() +#endif + #endif /* defined(_LINUX_DELAY_H) */ Index: linux-3.12.19-rt30/include/linux/ftrace_event.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/ftrace_event.h +++ linux-3.12.19-rt30/include/linux/ftrace_event.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:59 @ struct trace_entry { unsigned char flags; unsigned char preempt_count; int pid; + unsigned short migrate_disable; + unsigned short padding; + unsigned char preempt_lazy_count; }; #define FTRACE_MAX_EVENT \ Index: linux-3.12.19-rt30/include/linux/highmem.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/highmem.h +++ linux-3.12.19-rt30/include/linux/highmem.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:10 @ #include <linux/mm.h> #include <linux/uaccess.h> #include <linux/hardirq.h> +#include <linux/sched.h> #include <asm/cacheflush.h> @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:89 @ static inline void __kunmap_atomic(void #if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32) +#ifndef CONFIG_PREEMPT_RT_FULL DECLARE_PER_CPU(int, __kmap_atomic_idx); +#endif static inline int kmap_atomic_idx_push(void) { +#ifndef CONFIG_PREEMPT_RT_FULL int idx = __this_cpu_inc_return(__kmap_atomic_idx) - 1; -#ifdef CONFIG_DEBUG_HIGHMEM +# ifdef CONFIG_DEBUG_HIGHMEM WARN_ON_ONCE(in_irq() && !irqs_disabled()); BUG_ON(idx > KM_TYPE_NR); -#endif +# endif return idx; +#else + current->kmap_idx++; + BUG_ON(current->kmap_idx > KM_TYPE_NR); + return current->kmap_idx - 1; +#endif } static inline int kmap_atomic_idx(void) { +#ifndef CONFIG_PREEMPT_RT_FULL return __this_cpu_read(__kmap_atomic_idx) - 1; +#else + return current->kmap_idx - 1; +#endif } static inline void kmap_atomic_idx_pop(void) { -#ifdef CONFIG_DEBUG_HIGHMEM +#ifndef CONFIG_PREEMPT_RT_FULL +# ifdef CONFIG_DEBUG_HIGHMEM int idx = __this_cpu_dec_return(__kmap_atomic_idx); BUG_ON(idx < 0); -#else +# else __this_cpu_dec(__kmap_atomic_idx); +# endif +#else + current->kmap_idx--; +# ifdef CONFIG_DEBUG_HIGHMEM + BUG_ON(current->kmap_idx < 0); +# endif #endif } Index: linux-3.12.19-rt30/include/linux/hrtimer.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/hrtimer.h +++ linux-3.12.19-rt30/include/linux/hrtimer.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:114 @ struct hrtimer { enum hrtimer_restart (*function)(struct hrtimer *); struct hrtimer_clock_base *base; unsigned long state; + struct list_head cb_entry; + int irqsafe; +#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST + ktime_t praecox; +#endif #ifdef CONFIG_TIMER_STATS int start_pid; void *start_site; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:155 @ struct hrtimer_clock_base { int index; clockid_t clockid; struct timerqueue_head active; + struct list_head expired; ktime_t resolution; ktime_t (*get_time)(void); ktime_t softirq_time; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:199 @ struct hrtimer_cpu_base { unsigned long nr_hangs; ktime_t max_hang_time; #endif +#ifdef CONFIG_PREEMPT_RT_BASE + wait_queue_head_t wait; +#endif struct hrtimer_clock_base clock_base[HRTIMER_MAX_CLOCK_BASES]; }; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:397 @ static inline int hrtimer_restart(struct return hrtimer_start_expires(timer, HRTIMER_MODE_ABS); } +/* Softirq preemption could deadlock timer removal */ +#ifdef CONFIG_PREEMPT_RT_BASE + extern void hrtimer_wait_for_timer(const struct hrtimer *timer); +#else +# define hrtimer_wait_for_timer(timer) do { cpu_relax(); } while (0) +#endif + /* Query timers: */ extern ktime_t hrtimer_get_remaining(const struct hrtimer *timer); extern int hrtimer_get_res(const clockid_t which_clock, struct timespec *tp); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:464 @ extern int schedule_hrtimeout_range_cloc unsigned long delta, const enum hrtimer_mode mode, int clock); extern int schedule_hrtimeout(ktime_t *expires, const enum hrtimer_mode mode); -/* Soft interrupt function to run the hrtimer queues: */ +/* Called from the periodic timer tick */ extern void hrtimer_run_queues(void); -extern void hrtimer_run_pending(void); /* Bootup initialization: */ extern void __init hrtimers_init(void); Index: linux-3.12.19-rt30/include/linux/idr.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/idr.h +++ linux-3.12.19-rt30/include/linux/idr.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:95 @ void idr_init(struct idr *idp); * Each idr_preload() should be matched with an invocation of this * function. See idr_preload() for details. */ +#ifdef CONFIG_PREEMPT_RT_FULL +void idr_preload_end(void); +#else static inline void idr_preload_end(void) { preempt_enable(); } +#endif /** * idr_find - return pointer for given id Index: linux-3.12.19-rt30/include/linux/init_task.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/init_task.h +++ linux-3.12.19-rt30/include/linux/init_task.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:147 @ extern struct task_group root_task_group # define INIT_PERF_EVENTS(tsk) #endif +#ifdef CONFIG_PREEMPT_RT_BASE +# define INIT_TIMER_LIST .posix_timer_list = NULL, +#else +# define INIT_TIMER_LIST +#endif + #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN # define INIT_VTIME(tsk) \ - .vtime_seqlock = __SEQLOCK_UNLOCKED(tsk.vtime_seqlock), \ + .vtime_lock = __RAW_SPIN_LOCK_UNLOCKED(tsk.vtime_lock), \ + .vtime_seq = SEQCNT_ZERO, \ .vtime_snap = 0, \ .vtime_snap_whence = VTIME_SYS, #else @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:218 @ extern struct task_group root_task_group .cpu_timers = INIT_CPU_TIMERS(tsk.cpu_timers), \ .pi_lock = __RAW_SPIN_LOCK_UNLOCKED(tsk.pi_lock), \ .timer_slack_ns = 50000, /* 50 usec default slack */ \ + INIT_TIMER_LIST \ .pids = { \ [PIDTYPE_PID] = INIT_PID_LINK(PIDTYPE_PID), \ [PIDTYPE_PGID] = INIT_PID_LINK(PIDTYPE_PGID), \ Index: linux-3.12.19-rt30/include/linux/interrupt.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/interrupt.h +++ linux-3.12.19-rt30/include/linux/interrupt.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:61 @ * IRQF_NO_THREAD - Interrupt cannot be threaded * IRQF_EARLY_RESUME - Resume IRQ early during syscore instead of at device * resume time. + * IRQF_NO_SOFTIRQ_CALL - Do not process softirqs in the irq thread context (RT) */ #define IRQF_DISABLED 0x00000020 #define IRQF_SHARED 0x00000080 @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:75 @ #define IRQF_FORCE_RESUME 0x00008000 #define IRQF_NO_THREAD 0x00010000 #define IRQF_EARLY_RESUME 0x00020000 +#define IRQF_NO_SOFTIRQ_CALL 0x00040000 #define IRQF_TIMER (__IRQF_TIMER | IRQF_NO_SUSPEND | IRQF_NO_THREAD) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:181 @ extern void devm_free_irq(struct device #ifdef CONFIG_LOCKDEP # define local_irq_enable_in_hardirq() do { } while (0) #else -# define local_irq_enable_in_hardirq() local_irq_enable() +# define local_irq_enable_in_hardirq() local_irq_enable_nort() #endif extern void disable_irq_nosync(unsigned int irq); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:258 @ struct irq_affinity_notify { unsigned int irq; struct kref kref; struct work_struct work; + struct list_head list; void (*notify)(struct irq_affinity_notify *, const cpumask_t *mask); void (*release)(struct kref *ref); }; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:358 @ static inline int disable_irq_wake(unsig #ifdef CONFIG_IRQ_FORCED_THREADING +# ifndef CONFIG_PREEMPT_RT_BASE extern bool force_irqthreads; +# else +# define force_irqthreads (true) +# endif #else -#define force_irqthreads (0) +#define force_irqthreads (false) #endif #ifndef __ARCH_SET_SOFTIRQ_PENDING @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:420 @ struct softirq_action void (*action)(struct softirq_action *); }; +#ifndef CONFIG_PREEMPT_RT_FULL asmlinkage void do_softirq(void); asmlinkage void __do_softirq(void); +static inline void thread_do_softirq(void) { do_softirq(); } +#else +extern void thread_do_softirq(void); +#endif + extern void open_softirq(int nr, void (*action)(struct softirq_action *)); extern void softirq_init(void); extern void __raise_softirq_irqoff(unsigned int nr); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:435 @ extern void __raise_softirq_irqoff(unsig extern void raise_softirq_irqoff(unsigned int nr); extern void raise_softirq(unsigned int nr); +extern void softirq_check_pending_idle(void); + /* This is the worklist that queues up per-cpu softirq work. * * send_remote_sendirq() adds work to these lists, and @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:477 @ extern void __send_remote_softirq(struct to be executed on some cpu at least once after this. * If the tasklet is already scheduled, but its execution is still not started, it will be executed only once. - * If this tasklet is already running on another CPU (or schedule is called - from tasklet itself), it is rescheduled for later. + * If this tasklet is already running on another CPU, it is rescheduled + for later. + * Schedule must not be called from the tasklet itself (a lockup occurs) * Tasklet is strictly serialized wrt itself, but not wrt another tasklets. If client needs some intertask synchronization, he makes it with spinlocks. @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:504 @ struct tasklet_struct name = { NULL, 0, enum { TASKLET_STATE_SCHED, /* Tasklet is scheduled for execution */ - TASKLET_STATE_RUN /* Tasklet is running (SMP only) */ + TASKLET_STATE_RUN, /* Tasklet is running (SMP only) */ + TASKLET_STATE_PENDING /* Tasklet is pending */ }; -#ifdef CONFIG_SMP +#define TASKLET_STATEF_SCHED (1 << TASKLET_STATE_SCHED) +#define TASKLET_STATEF_RUN (1 << TASKLET_STATE_RUN) +#define TASKLET_STATEF_PENDING (1 << TASKLET_STATE_PENDING) + +#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT_FULL) static inline int tasklet_trylock(struct tasklet_struct *t) { return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state); } +static inline int tasklet_tryunlock(struct tasklet_struct *t) +{ + return cmpxchg(&t->state, TASKLET_STATEF_RUN, 0) == TASKLET_STATEF_RUN; +} + static inline void tasklet_unlock(struct tasklet_struct *t) { smp_mb__before_clear_bit(); clear_bit(TASKLET_STATE_RUN, &(t)->state); } -static inline void tasklet_unlock_wait(struct tasklet_struct *t) -{ - while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); } -} +extern void tasklet_unlock_wait(struct tasklet_struct *t); + #else #define tasklet_trylock(t) 1 +#define tasklet_tryunlock(t) 1 #define tasklet_unlock_wait(t) do { } while (0) #define tasklet_unlock(t) do { } while (0) #endif @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:582 @ static inline void tasklet_disable(struc smp_mb(); } -static inline void tasklet_enable(struct tasklet_struct *t) -{ - smp_mb__before_atomic_dec(); - atomic_dec(&t->count); -} - -static inline void tasklet_hi_enable(struct tasklet_struct *t) -{ - smp_mb__before_atomic_dec(); - atomic_dec(&t->count); -} +extern void tasklet_enable(struct tasklet_struct *t); +extern void tasklet_hi_enable(struct tasklet_struct *t); extern void tasklet_kill(struct tasklet_struct *t); extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:615 @ void tasklet_hrtimer_cancel(struct taskl tasklet_kill(&ttimer->tasklet); } +#ifdef CONFIG_PREEMPT_RT_FULL +extern void softirq_early_init(void); +#else +static inline void softirq_early_init(void) { } +#endif + /* * Autoprobing for irqs: * Index: linux-3.12.19-rt30/include/linux/irq.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/irq.h +++ linux-3.12.19-rt30/include/linux/irq.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:73 @ typedef void (*irq_preflow_handler_t)(st * IRQ_MOVE_PCNTXT - Interrupt can be migrated from process context * IRQ_NESTED_TRHEAD - Interrupt nests into another thread * IRQ_PER_CPU_DEVID - Dev_id is a per-cpu variable + * IRQ_NO_SOFTIRQ_CALL - No softirq processing in the irq thread context (RT) */ enum { IRQ_TYPE_NONE = 0x00000000, @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:98 @ enum { IRQ_NESTED_THREAD = (1 << 15), IRQ_NOTHREAD = (1 << 16), IRQ_PER_CPU_DEVID = (1 << 17), + IRQ_NO_SOFTIRQ_CALL = (1 << 18), }; #define IRQF_MODIFY_MASK \ (IRQ_TYPE_SENSE_MASK | IRQ_NOPROBE | IRQ_NOREQUEST | \ IRQ_NOAUTOEN | IRQ_MOVE_PCNTXT | IRQ_LEVEL | IRQ_NO_BALANCING | \ - IRQ_PER_CPU | IRQ_NESTED_THREAD | IRQ_NOTHREAD | IRQ_PER_CPU_DEVID) + IRQ_PER_CPU | IRQ_NESTED_THREAD | IRQ_NOTHREAD | IRQ_PER_CPU_DEVID | \ + IRQ_NO_SOFTIRQ_CALL) #define IRQ_NO_BALANCING_MASK (IRQ_PER_CPU | IRQ_NO_BALANCING) Index: linux-3.12.19-rt30/include/linux/irq_work.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/irq_work.h +++ linux-3.12.19-rt30/include/linux/irq_work.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:19 @ #define IRQ_WORK_BUSY 2UL #define IRQ_WORK_FLAGS 3UL #define IRQ_WORK_LAZY 4UL /* Doesn't want IPI, wait for tick */ +#define IRQ_WORK_HARD_IRQ 8UL /* Run hard IRQ context, even on RT */ struct irq_work { unsigned long flags; Index: linux-3.12.19-rt30/include/linux/irqdesc.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/irqdesc.h +++ linux-3.12.19-rt30/include/linux/irqdesc.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:59 @ 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; #ifdef CONFIG_SMP Index: linux-3.12.19-rt30/include/linux/irqflags.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/irqflags.h +++ linux-3.12.19-rt30/include/linux/irqflags.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:28 @ # define trace_softirqs_enabled(p) ((p)->softirqs_enabled) # define trace_hardirq_enter() do { current->hardirq_context++; } while (0) # define trace_hardirq_exit() do { current->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 INIT_TRACE_IRQFLAGS .softirqs_enabled = 1, #else # define trace_hardirqs_on() do { } while (0) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:40 @ # define trace_softirqs_enabled(p) 0 # define trace_hardirq_enter() do { } while (0) # define trace_hardirq_exit() do { } while (0) +# define INIT_TRACE_IRQFLAGS +#endif + +#if defined(CONFIG_TRACE_IRQFLAGS) && !defined(CONFIG_PREEMPT_RT_FULL) +# 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) -# define INIT_TRACE_IRQFLAGS #endif #if defined(CONFIG_IRQSOFF_TRACER) || \ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:154 @ #endif /* CONFIG_TRACE_IRQFLAGS_SUPPORT */ +/* + * local_irq* variants depending on RT/!RT + */ +#ifdef CONFIG_PREEMPT_RT_FULL +# define local_irq_disable_nort() do { } while (0) +# define local_irq_enable_nort() do { } while (0) +# define local_irq_save_nort(flags) local_save_flags(flags) +# define local_irq_restore_nort(flags) (void)(flags) +# define local_irq_disable_rt() local_irq_disable() +# define local_irq_enable_rt() local_irq_enable() +#else +# define local_irq_disable_nort() local_irq_disable() +# define local_irq_enable_nort() local_irq_enable() +# define local_irq_save_nort(flags) local_irq_save(flags) +# define local_irq_restore_nort(flags) local_irq_restore(flags) +# define local_irq_disable_rt() do { } while (0) +# define local_irq_enable_rt() do { } while (0) +#endif + #endif Index: linux-3.12.19-rt30/include/linux/jbd_common.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/jbd_common.h +++ linux-3.12.19-rt30/include/linux/jbd_common.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:18 @ static inline struct journal_head *bh2jh static inline void jbd_lock_bh_state(struct buffer_head *bh) { +#ifndef CONFIG_PREEMPT_RT_BASE bit_spin_lock(BH_State, &bh->b_state); +#else + spin_lock(&bh->b_state_lock); +#endif } static inline int jbd_trylock_bh_state(struct buffer_head *bh) { +#ifndef CONFIG_PREEMPT_RT_BASE return bit_spin_trylock(BH_State, &bh->b_state); +#else + return spin_trylock(&bh->b_state_lock); +#endif } static inline int jbd_is_locked_bh_state(struct buffer_head *bh) { +#ifndef CONFIG_PREEMPT_RT_BASE return bit_spin_is_locked(BH_State, &bh->b_state); +#else + return spin_is_locked(&bh->b_state_lock); +#endif } static inline void jbd_unlock_bh_state(struct buffer_head *bh) { +#ifndef CONFIG_PREEMPT_RT_BASE bit_spin_unlock(BH_State, &bh->b_state); +#else + spin_unlock(&bh->b_state_lock); +#endif } static inline void jbd_lock_bh_journal_head(struct buffer_head *bh) { +#ifndef CONFIG_PREEMPT_RT_BASE bit_spin_lock(BH_JournalHead, &bh->b_state); +#else + spin_lock(&bh->b_journal_head_lock); +#endif } static inline void jbd_unlock_bh_journal_head(struct buffer_head *bh) { +#ifndef CONFIG_PREEMPT_RT_BASE bit_spin_unlock(BH_JournalHead, &bh->b_state); +#else + spin_unlock(&bh->b_journal_head_lock); +#endif } #endif Index: linux-3.12.19-rt30/include/linux/jump_label.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/jump_label.h +++ linux-3.12.19-rt30/include/linux/jump_label.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:52 @ #include <linux/types.h> #include <linux/compiler.h> -#if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL) +#if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL) && \ + !defined(CONFIG_PREEMPT_BASE) struct static_key { atomic_t enabled; Index: linux-3.12.19-rt30/include/linux/kdb.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/kdb.h +++ linux-3.12.19-rt30/include/linux/kdb.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:118 @ extern int kdb_trap_printk; extern __printf(1, 0) int vkdb_printf(const char *fmt, va_list args); extern __printf(1, 2) int kdb_printf(const char *, ...); typedef __printf(1, 2) int (*kdb_printf_t)(const char *, ...); - +#define in_kdb_printk() (kdb_trap_printk) extern void kdb_init(int level); /* Access to kdb specific polling devices */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:153 @ extern int kdb_register_repeat(char *, k extern int kdb_unregister(char *); #else /* ! CONFIG_KGDB_KDB */ static inline __printf(1, 2) int kdb_printf(const char *fmt, ...) { return 0; } +#define in_kdb_printk() (0) static inline void kdb_init(int level) {} static inline int kdb_register(char *cmd, kdb_func_t func, char *usage, char *help, short minlen) { return 0; } Index: linux-3.12.19-rt30/include/linux/kernel.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/kernel.h +++ linux-3.12.19-rt30/include/linux/kernel.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:415 @ extern enum system_states { SYSTEM_HALT, SYSTEM_POWER_OFF, SYSTEM_RESTART, + SYSTEM_SUSPEND, } system_state; #define TAINT_PROPRIETARY_MODULE 0 Index: linux-3.12.19-rt30/include/linux/lglock.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/lglock.h +++ linux-3.12.19-rt30/include/linux/lglock.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:45 @ #endif struct lglock { +#ifndef CONFIG_PREEMPT_RT_FULL arch_spinlock_t __percpu *lock; +#else + struct rt_mutex __percpu *lock; +#endif #ifdef CONFIG_DEBUG_LOCK_ALLOC struct lock_class_key lock_key; struct lockdep_map lock_dep_map; #endif }; -#define DEFINE_LGLOCK(name) \ +#ifndef CONFIG_PREEMPT_RT_FULL +# define DEFINE_LGLOCK(name) \ static DEFINE_PER_CPU(arch_spinlock_t, name ## _lock) \ = __ARCH_SPIN_LOCK_UNLOCKED; \ struct lglock name = { .lock = &name ## _lock } -#define DEFINE_STATIC_LGLOCK(name) \ +# define DEFINE_STATIC_LGLOCK(name) \ static DEFINE_PER_CPU(arch_spinlock_t, name ## _lock) \ = __ARCH_SPIN_LOCK_UNLOCKED; \ static struct lglock name = { .lock = &name ## _lock } +#else + +# define DEFINE_LGLOCK(name) \ + static DEFINE_PER_CPU(struct rt_mutex, name ## _lock); \ + struct lglock name = { .lock = &name ## _lock } + +# define DEFINE_STATIC_LGLOCK(name) \ + static DEFINE_PER_CPU(struct rt_mutex, name ## _lock); \ + static struct lglock name = { .lock = &name ## _lock } +#endif void lg_lock_init(struct lglock *lg, char *name); void lg_local_lock(struct lglock *lg); Index: linux-3.12.19-rt30/include/linux/list.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/list.h +++ linux-3.12.19-rt30/include/linux/list.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:376 @ static inline void list_splice_tail_init (!list_empty(ptr) ? list_first_entry(ptr, type, member) : NULL) /** + * list_last_entry - get the last element from a list + * @ptr: the list head to take the element from. + * @type: the type of the struct this is embedded in. + * @member: the name of the list_struct within the struct. + * + * Note, that list is expected to be not empty. + */ +#define list_last_entry(ptr, type, member) \ + list_entry((ptr)->prev, type, member) + +/** * list_next_entry - get the next element in list * @pos: the type * to cursor * @member: the name of the list_struct within the struct. Index: linux-3.12.19-rt30/include/linux/list_bl.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/list_bl.h +++ linux-3.12.19-rt30/include/linux/list_bl.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:5 @ #define _LINUX_LIST_BL_H #include <linux/list.h> +#include <linux/spinlock.h> #include <linux/bit_spinlock.h> /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:36 @ struct hlist_bl_head { struct hlist_bl_node *first; +#ifdef CONFIG_PREEMPT_RT_BASE + raw_spinlock_t lock; +#endif }; struct hlist_bl_node { struct hlist_bl_node *next, **pprev; }; -#define INIT_HLIST_BL_HEAD(ptr) \ - ((ptr)->first = NULL) + +static inline void INIT_HLIST_BL_HEAD(struct hlist_bl_head *h) +{ + h->first = NULL; +#ifdef CONFIG_PREEMPT_RT_BASE + raw_spin_lock_init(&h->lock); +#endif +} static inline void INIT_HLIST_BL_NODE(struct hlist_bl_node *h) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:130 @ static inline void hlist_bl_del_init(str static inline void hlist_bl_lock(struct hlist_bl_head *b) { +#ifndef CONFIG_PREEMPT_RT_BASE bit_spin_lock(0, (unsigned long *)b); +#else + raw_spin_lock(&b->lock); +#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) + __set_bit(0, (unsigned long *)b); +#endif +#endif } static inline void hlist_bl_unlock(struct hlist_bl_head *b) { +#ifndef CONFIG_PREEMPT_RT_BASE __bit_spin_unlock(0, (unsigned long *)b); +#else +#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) + __clear_bit(0, (unsigned long *)b); +#endif + raw_spin_unlock(&b->lock); +#endif } static inline bool hlist_bl_is_locked(struct hlist_bl_head *b) Index: linux-3.12.19-rt30/include/linux/locallock.h =================================================================== --- /dev/null +++ linux-3.12.19-rt30/include/linux/locallock.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:4 @ +#ifndef _LINUX_LOCALLOCK_H +#define _LINUX_LOCALLOCK_H + +#include <linux/percpu.h> +#include <linux/spinlock.h> + +#ifdef CONFIG_PREEMPT_RT_BASE + +#ifdef CONFIG_DEBUG_SPINLOCK +# define LL_WARN(cond) WARN_ON(cond) +#else +# define LL_WARN(cond) do { } while (0) +#endif + +/* + * per cpu lock based substitute for local_irq_*() + */ +struct local_irq_lock { + spinlock_t lock; + struct task_struct *owner; + int nestcnt; + unsigned long flags; +}; + +#define DEFINE_LOCAL_IRQ_LOCK(lvar) \ + DEFINE_PER_CPU(struct local_irq_lock, lvar) = { \ + .lock = __SPIN_LOCK_UNLOCKED((lvar).lock) } + +#define DECLARE_LOCAL_IRQ_LOCK(lvar) \ + DECLARE_PER_CPU(struct local_irq_lock, lvar) + +#define local_irq_lock_init(lvar) \ + do { \ + int __cpu; \ + for_each_possible_cpu(__cpu) \ + spin_lock_init(&per_cpu(lvar, __cpu).lock); \ + } while (0) + +/* + * spin_lock|trylock|unlock_local flavour that does not migrate disable + * used for __local_lock|trylock|unlock where get_local_var/put_local_var + * already takes care of the migrate_disable/enable + * for CONFIG_PREEMPT_BASE map to the normal spin_* calls. + */ +#ifdef CONFIG_PREEMPT_RT_FULL +# define spin_lock_local(lock) rt_spin_lock(lock) +# define spin_trylock_local(lock) rt_spin_trylock(lock) +# define spin_unlock_local(lock) rt_spin_unlock(lock) +#else +# define spin_lock_local(lock) spin_lock(lock) +# define spin_trylock_local(lock) spin_trylock(lock) +# define spin_unlock_local(lock) spin_unlock(lock) +#endif + +static inline void __local_lock(struct local_irq_lock *lv) +{ + if (lv->owner != current) { + spin_lock_local(&lv->lock); + LL_WARN(lv->owner); + LL_WARN(lv->nestcnt); + lv->owner = current; + } + lv->nestcnt++; +} + +#define local_lock(lvar) \ + do { __local_lock(&get_local_var(lvar)); } while (0) + +static inline int __local_trylock(struct local_irq_lock *lv) +{ + if (lv->owner != current && spin_trylock_local(&lv->lock)) { + LL_WARN(lv->owner); + LL_WARN(lv->nestcnt); + lv->owner = current; + lv->nestcnt = 1; + return 1; + } + return 0; +} + +#define local_trylock(lvar) \ + ({ \ + int __locked; \ + __locked = __local_trylock(&get_local_var(lvar)); \ + if (!__locked) \ + put_local_var(lvar); \ + __locked; \ + }) + +static inline void __local_unlock(struct local_irq_lock *lv) +{ + LL_WARN(lv->nestcnt == 0); + LL_WARN(lv->owner != current); + if (--lv->nestcnt) + return; + + lv->owner = NULL; + spin_unlock_local(&lv->lock); +} + +#define local_unlock(lvar) \ + do { \ + __local_unlock(&__get_cpu_var(lvar)); \ + put_local_var(lvar); \ + } while (0) + +static inline void __local_lock_irq(struct local_irq_lock *lv) +{ + spin_lock_irqsave(&lv->lock, lv->flags); + LL_WARN(lv->owner); + LL_WARN(lv->nestcnt); + lv->owner = current; + lv->nestcnt = 1; +} + +#define local_lock_irq(lvar) \ + do { __local_lock_irq(&get_local_var(lvar)); } while (0) + +#define local_lock_irq_on(lvar, cpu) \ + do { __local_lock_irq(&per_cpu(lvar, cpu)); } while (0) + +static inline void __local_unlock_irq(struct local_irq_lock *lv) +{ + LL_WARN(!lv->nestcnt); + LL_WARN(lv->owner != current); + lv->owner = NULL; + lv->nestcnt = 0; + spin_unlock_irq(&lv->lock); +} + +#define local_unlock_irq(lvar) \ + do { \ + __local_unlock_irq(&__get_cpu_var(lvar)); \ + put_local_var(lvar); \ + } while (0) + +#define local_unlock_irq_on(lvar, cpu) \ + do { \ + __local_unlock_irq(&per_cpu(lvar, cpu)); \ + } while (0) + +static inline int __local_lock_irqsave(struct local_irq_lock *lv) +{ + if (lv->owner != current) { + __local_lock_irq(lv); + return 0; + } else { + lv->nestcnt++; + return 1; + } +} + +#define local_lock_irqsave(lvar, _flags) \ + do { \ + if (__local_lock_irqsave(&get_local_var(lvar))) \ + put_local_var(lvar); \ + _flags = __get_cpu_var(lvar).flags; \ + } while (0) + +#define local_lock_irqsave_on(lvar, _flags, cpu) \ + do { \ + __local_lock_irqsave(&per_cpu(lvar, cpu)); \ + _flags = per_cpu(lvar, cpu).flags; \ + } while (0) + +static inline int __local_unlock_irqrestore(struct local_irq_lock *lv, + unsigned long flags) +{ + LL_WARN(!lv->nestcnt); + LL_WARN(lv->owner != current); + if (--lv->nestcnt) + return 0; + + lv->owner = NULL; + spin_unlock_irqrestore(&lv->lock, lv->flags); + return 1; +} + +#define local_unlock_irqrestore(lvar, flags) \ + do { \ + if (__local_unlock_irqrestore(&__get_cpu_var(lvar), flags)) \ + put_local_var(lvar); \ + } while (0) + +#define local_unlock_irqrestore_on(lvar, flags, cpu) \ + do { \ + __local_unlock_irqrestore(&per_cpu(lvar, cpu), flags); \ + } while (0) + +#define local_spin_trylock_irq(lvar, lock) \ + ({ \ + int __locked; \ + local_lock_irq(lvar); \ + __locked = spin_trylock(lock); \ + if (!__locked) \ + local_unlock_irq(lvar); \ + __locked; \ + }) + +#define local_spin_lock_irq(lvar, lock) \ + do { \ + local_lock_irq(lvar); \ + spin_lock(lock); \ + } while (0) + +#define local_spin_unlock_irq(lvar, lock) \ + do { \ + spin_unlock(lock); \ + local_unlock_irq(lvar); \ + } while (0) + +#define local_spin_lock_irqsave(lvar, lock, flags) \ + do { \ + local_lock_irqsave(lvar, flags); \ + spin_lock(lock); \ + } while (0) + +#define local_spin_unlock_irqrestore(lvar, lock, flags) \ + do { \ + spin_unlock(lock); \ + local_unlock_irqrestore(lvar, flags); \ + } while (0) + +#define get_locked_var(lvar, var) \ + (*({ \ + local_lock(lvar); \ + &__get_cpu_var(var); \ + })) + +#define put_locked_var(lvar, var) local_unlock(lvar); + +#define local_lock_cpu(lvar) \ + ({ \ + local_lock(lvar); \ + smp_processor_id(); \ + }) + +#define local_unlock_cpu(lvar) local_unlock(lvar) + +#else /* PREEMPT_RT_BASE */ + +#define DEFINE_LOCAL_IRQ_LOCK(lvar) __typeof__(const int) lvar +#define DECLARE_LOCAL_IRQ_LOCK(lvar) extern __typeof__(const int) lvar + +static inline void local_irq_lock_init(int lvar) { } + +#define local_lock(lvar) preempt_disable() +#define local_unlock(lvar) preempt_enable() +#define local_lock_irq(lvar) local_irq_disable() +#define local_unlock_irq(lvar) local_irq_enable() +#define local_lock_irqsave(lvar, flags) local_irq_save(flags) +#define local_unlock_irqrestore(lvar, flags) local_irq_restore(flags) + +#define local_spin_trylock_irq(lvar, lock) spin_trylock_irq(lock) +#define local_spin_lock_irq(lvar, lock) spin_lock_irq(lock) +#define local_spin_unlock_irq(lvar, lock) spin_unlock_irq(lock) +#define local_spin_lock_irqsave(lvar, lock, flags) \ + spin_lock_irqsave(lock, flags) +#define local_spin_unlock_irqrestore(lvar, lock, flags) \ + spin_unlock_irqrestore(lock, flags) + +#define get_locked_var(lvar, var) get_cpu_var(var) +#define put_locked_var(lvar, var) put_cpu_var(var) + +#define local_lock_cpu(lvar) get_cpu() +#define local_unlock_cpu(lvar) put_cpu() + +#endif + +#endif Index: linux-3.12.19-rt30/include/linux/mm.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/mm.h +++ linux-3.12.19-rt30/include/linux/mm.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1263 @ static inline pmd_t *pmd_alloc(struct mm * overflow into the next struct page (as it might with DEBUG_SPINLOCK). * When freeing, reset page->mapping so free_pages_check won't complain. */ +#ifndef CONFIG_PREEMPT_RT_FULL + #define __pte_lockptr(page) &((page)->ptl) -#define pte_lock_init(_page) do { \ - spin_lock_init(__pte_lockptr(_page)); \ -} while (0) + +static inline struct page *pte_lock_init(struct page *page) +{ + spin_lock_init(__pte_lockptr(page)); + return page; +} + #define pte_lock_deinit(page) ((page)->mapping = NULL) + +#else /* !PREEMPT_RT_FULL */ + +/* + * On PREEMPT_RT_FULL the spinlock_t's are too large to embed in the + * page frame, hence it only has a pointer and we need to dynamically + * allocate the lock when we allocate PTE-pages. + * + * This is an overall win, since only a small fraction of the pages + * will be PTE pages under normal circumstances. + */ + +#define __pte_lockptr(page) ((page)->ptl) + +extern struct page *pte_lock_init(struct page *page); +extern void pte_lock_deinit(struct page *page); + +#endif /* PREEMPT_RT_FULL */ + #define pte_lockptr(mm, pmd) ({(void)(mm); __pte_lockptr(pmd_page(*(pmd)));}) #else /* !USE_SPLIT_PTLOCKS */ /* * We use mm->page_table_lock to guard all pagetable pages of the mm. */ -#define pte_lock_init(page) do {} while (0) +static inline struct page *pte_lock_init(struct page *page) { return page; } #define pte_lock_deinit(page) do {} while (0) #define pte_lockptr(mm, pmd) ({(void)(pmd); &(mm)->page_table_lock;}) #endif /* USE_SPLIT_PTLOCKS */ -static inline void pgtable_page_ctor(struct page *page) +static inline struct page *__pgtable_page_ctor(struct page *page) { - pte_lock_init(page); - inc_zone_page_state(page, NR_PAGETABLE); + page = pte_lock_init(page); + if (page) + inc_zone_page_state(page, NR_PAGETABLE); + return page; } +#define pgtable_page_ctor(page) \ +do { \ + page = __pgtable_page_ctor(page); \ +} while (0) + static inline void pgtable_page_dtor(struct page *page) { pte_lock_deinit(page); Index: linux-3.12.19-rt30/include/linux/mm_types.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/mm_types.h +++ linux-3.12.19-rt30/include/linux/mm_types.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:14 @ #include <linux/completion.h> #include <linux/cpumask.h> #include <linux/page-debug-flags.h> +#include <linux/rcupdate.h> #include <linux/uprobes.h> #include <linux/page-flags-layout.h> #include <asm/page.h> @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:146 @ struct page { * system if PG_buddy is set. */ #if USE_SPLIT_PTLOCKS +# ifndef CONFIG_PREEMPT_RT_FULL spinlock_t ptl; +# else + spinlock_t *ptl; +# endif #endif struct kmem_cache *slab_cache; /* SL[AU]B: Pointer to slab */ struct page *first_page; /* Compound tail pages */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:452 @ struct mm_struct { bool tlb_flush_pending; #endif struct uprobes_state uprobes_state; +#ifdef CONFIG_PREEMPT_RT_BASE + struct rcu_head delayed_drop; +#endif }; /* first nid will either be a valid NID or one of these values */ Index: linux-3.12.19-rt30/include/linux/mutex.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/mutex.h +++ linux-3.12.19-rt30/include/linux/mutex.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:21 @ #include <linux/atomic.h> #include <asm/processor.h> +#ifdef CONFIG_DEBUG_LOCK_ALLOC +# define __DEP_MAP_MUTEX_INITIALIZER(lockname) \ + , .dep_map = { .name = #lockname } +#else +# define __DEP_MAP_MUTEX_INITIALIZER(lockname) +#endif + +#ifdef CONFIG_PREEMPT_RT_FULL +# include <linux/mutex_rt.h> +#else + /* * Simple, straightforward mutexes with strict semantics: * @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:113 @ do { \ static inline void mutex_destroy(struct mutex *lock) {} #endif -#ifdef CONFIG_DEBUG_LOCK_ALLOC -# define __DEP_MAP_MUTEX_INITIALIZER(lockname) \ - , .dep_map = { .name = #lockname } -#else -# define __DEP_MAP_MUTEX_INITIALIZER(lockname) -#endif - #define __MUTEX_INITIALIZER(lockname) \ { .count = ATOMIC_INIT(1) \ , .wait_lock = __SPIN_LOCK_UNLOCKED(lockname.wait_lock) \ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:180 @ extern int __must_check mutex_lock_killa extern int mutex_trylock(struct mutex *lock); extern void mutex_unlock(struct mutex *lock); +#endif /* !PREEMPT_RT_FULL */ + extern int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock); #ifndef arch_mutex_cpu_relax Index: linux-3.12.19-rt30/include/linux/mutex_rt.h =================================================================== --- /dev/null +++ linux-3.12.19-rt30/include/linux/mutex_rt.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:4 @ +#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 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_destroy(l) rt_mutex_destroy(&(l)->lock) + +#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_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) +#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) + +#endif Index: linux-3.12.19-rt30/include/linux/netdevice.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/netdevice.h +++ linux-3.12.19-rt30/include/linux/netdevice.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1217 @ struct net_device { unsigned char perm_addr[MAX_ADDR_LEN]; /* permanent hw address */ unsigned char addr_assign_type; /* hw address assignment type */ unsigned char addr_len; /* hardware address length */ - unsigned char neigh_priv_len; + unsigned short neigh_priv_len; unsigned short dev_id; /* Used to differentiate devices * that share the same link * layer address @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1933 @ struct softnet_data { unsigned int dropped; struct sk_buff_head input_pkt_queue; struct napi_struct backlog; + struct sk_buff_head tofree_queue; #ifdef CONFIG_NET_FLOW_LIMIT struct sd_flow_limit __rcu *flow_limit; Index: linux-3.12.19-rt30/include/linux/netfilter/x_tables.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/netfilter/x_tables.h +++ linux-3.12.19-rt30/include/linux/netfilter/x_tables.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:6 @ #include <linux/netdevice.h> +#include <linux/locallock.h> #include <uapi/linux/netfilter/x_tables.h> /** @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:288 @ extern void xt_free_table_info(struct xt */ DECLARE_PER_CPU(seqcount_t, xt_recseq); +DECLARE_LOCAL_IRQ_LOCK(xt_write_lock); + /** * xt_write_recseq_begin - start of a write section * @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:304 @ static inline unsigned int xt_write_recs { unsigned int addend; + /* RT protection */ + local_lock(xt_write_lock); + /* * Low order bit of sequence is set if we already * called xt_write_recseq_begin(). @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:337 @ static inline void xt_write_recseq_end(u /* this is kind of a write_seqcount_end(), but addend is 0 or 1 */ smp_wmb(); __this_cpu_add(xt_recseq.sequence, addend); + local_unlock(xt_write_lock); } /* Index: linux-3.12.19-rt30/include/linux/notifier.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/notifier.h +++ linux-3.12.19-rt30/include/linux/notifier.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:9 @ * * Alan Cox <Alan.Cox@linux.org> */ - + #ifndef _LINUX_NOTIFIER_H #define _LINUX_NOTIFIER_H #include <linux/errno.h> @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:45 @ * in srcu_notifier_call_chain(): no cache bounces and no memory barriers. * As compensation, srcu_notifier_chain_unregister() is rather expensive. * SRCU notifier chains should be used when the chain will be called very - * often but notifier_blocks will seldom be removed. Also, SRCU notifier - * chains are slightly more difficult to use because they require special - * runtime initialization. + * often but notifier_blocks will seldom be removed. */ typedef int (*notifier_fn_t)(struct notifier_block *nb, @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:89 @ struct srcu_notifier_head { (name)->head = NULL; \ } while (0) -/* srcu_notifier_heads must be initialized and cleaned up dynamically */ +/* srcu_notifier_heads must be cleaned up dynamically */ extern void srcu_init_notifier_head(struct srcu_notifier_head *nh); #define srcu_cleanup_notifier_head(name) \ cleanup_srcu_struct(&(name)->srcu); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:102 @ extern void srcu_init_notifier_head(stru .head = NULL } #define RAW_NOTIFIER_INIT(name) { \ .head = NULL } -/* srcu_notifier_heads cannot be initialized statically */ + +#define SRCU_NOTIFIER_INIT(name, pcpu) \ + { \ + .mutex = __MUTEX_INITIALIZER(name.mutex), \ + .head = NULL, \ + .srcu = __SRCU_STRUCT_INIT(name.srcu, pcpu), \ + } #define ATOMIC_NOTIFIER_HEAD(name) \ struct atomic_notifier_head name = \ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:120 @ extern void srcu_init_notifier_head(stru struct raw_notifier_head name = \ RAW_NOTIFIER_INIT(name) +#define _SRCU_NOTIFIER_HEAD(name, mod) \ + static DEFINE_PER_CPU(struct srcu_struct_array, \ + name##_head_srcu_array); \ + mod struct srcu_notifier_head name = \ + SRCU_NOTIFIER_INIT(name, name##_head_srcu_array) + +#define SRCU_NOTIFIER_HEAD(name) \ + _SRCU_NOTIFIER_HEAD(name, ) + +#define SRCU_NOTIFIER_HEAD_STATIC(name) \ + _SRCU_NOTIFIER_HEAD(name, static) + #ifdef __KERNEL__ extern int atomic_notifier_chain_register(struct atomic_notifier_head *nh, @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:201 @ static inline int notifier_to_errno(int /* * Declared notifiers so far. I can imagine quite a few more chains - * over time (eg laptop power reset chains, reboot chain (to clean + * over time (eg laptop power reset chains, reboot chain (to clean * device units up), device [un]mount chain, module load/unload chain, - * low memory chain, screenblank chain (for plug in modular screenblankers) + * low memory chain, screenblank chain (for plug in modular screenblankers) * VC switch chains (for loadable kernel svgalib VC switch helpers) etc... */ - + /* CPU notfiers are defined in include/linux/cpu.h. */ /* netdevice notifiers are defined in include/linux/netdevice.h */ Index: linux-3.12.19-rt30/include/linux/page_cgroup.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/page_cgroup.h +++ linux-3.12.19-rt30/include/linux/page_cgroup.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:27 @ enum { */ struct page_cgroup { unsigned long flags; +#ifdef CONFIG_PREEMPT_RT_BASE + spinlock_t pcg_lock; +#endif struct mem_cgroup *mem_cgroup; }; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:80 @ static inline void lock_page_cgroup(stru * Don't take this lock in IRQ context. * This lock is for pc->mem_cgroup, USED, MIGRATION */ +#ifndef CONFIG_PREEMPT_RT_BASE bit_spin_lock(PCG_LOCK, &pc->flags); +#else + spin_lock(&pc->pcg_lock); +#endif } static inline void unlock_page_cgroup(struct page_cgroup *pc) { +#ifndef CONFIG_PREEMPT_RT_BASE bit_spin_unlock(PCG_LOCK, &pc->flags); +#else + spin_unlock(&pc->pcg_lock); +#endif } #else /* CONFIG_MEMCG */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:116 @ static inline void __init page_cgroup_in { } +static inline void page_cgroup_lock_init(struct page_cgroup *pc) +{ +} + #endif /* CONFIG_MEMCG */ #include <linux/swap.h> Index: linux-3.12.19-rt30/include/linux/percpu.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/percpu.h +++ linux-3.12.19-rt30/include/linux/percpu.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:51 @ preempt_enable(); \ } while (0) +#ifndef CONFIG_PREEMPT_RT_FULL +# define get_local_var(var) get_cpu_var(var) +# define put_local_var(var) put_cpu_var(var) +# define get_local_ptr(var) get_cpu_ptr(var) +# define put_local_ptr(var) put_cpu_ptr(var) +#else +# define get_local_var(var) (*({ \ + migrate_disable(); \ + &__get_cpu_var(var); })) + +# define put_local_var(var) do { \ + (void)&(var); \ + migrate_enable(); \ +} while (0) + +# define get_local_ptr(var) ({ \ + migrate_disable(); \ + this_cpu_ptr(var); }) + +# define put_local_ptr(var) do { \ + (void)(var); \ + migrate_enable(); \ +} while (0) +#endif + /* minimum unit size, also is the maximum supported allocation size */ #define PCPU_MIN_UNIT_SIZE PFN_ALIGN(32 << 10) Index: linux-3.12.19-rt30/include/linux/pid.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/pid.h +++ linux-3.12.19-rt30/include/linux/pid.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:5 @ #define _LINUX_PID_H #include <linux/rcupdate.h> +#include <linux/atomic.h> enum pid_type { Index: linux-3.12.19-rt30/include/linux/preempt.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/preempt.h +++ linux-3.12.19-rt30/include/linux/preempt.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:26 @ #define preempt_count() (current_thread_info()->preempt_count) +#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 asmlinkage void preempt_schedule(void); +# ifdef CONFIG_PREEMPT_LAZY #define preempt_check_resched() \ do { \ - if (unlikely(test_thread_flag(TIF_NEED_RESCHED))) \ + if (unlikely(test_thread_flag(TIF_NEED_RESCHED) || \ + test_thread_flag(TIF_NEED_RESCHED_LAZY))) \ + preempt_schedule(); \ +} while (0) +# else +#define preempt_check_resched() \ +do { \ + if (unlikely(test_thread_flag(TIF_NEED_RESCHED))) \ preempt_schedule(); \ } while (0) +# endif #ifdef CONFIG_CONTEXT_TRACKING @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:90 @ do { \ barrier(); \ } while (0) +#define preempt_lazy_disable() \ +do { \ + inc_preempt_lazy_count(); \ + barrier(); \ +} while (0) + #define sched_preempt_enable_no_resched() \ do { \ barrier(); \ dec_preempt_count(); \ } while (0) -#define preempt_enable_no_resched() sched_preempt_enable_no_resched() +#ifndef CONFIG_PREEMPT_RT_BASE +# 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 preempt_enable() \ do { \ - preempt_enable_no_resched(); \ + sched_preempt_enable_no_resched(); \ + barrier(); \ + preempt_check_resched(); \ +} while (0) + +#define preempt_lazy_enable() \ +do { \ + dec_preempt_lazy_count(); \ barrier(); \ preempt_check_resched(); \ } while (0) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:168 @ do { \ #define preempt_disable_notrace() barrier() #define preempt_enable_no_resched_notrace() barrier() #define preempt_enable_notrace() barrier() +#define preempt_check_resched_rt() barrier() #endif /* CONFIG_PREEMPT_COUNT */ +#ifdef CONFIG_PREEMPT_RT_FULL +# define preempt_disable_rt() preempt_disable() +# define preempt_enable_rt() preempt_enable() +# define preempt_disable_nort() barrier() +# define preempt_enable_nort() barrier() +# ifdef CONFIG_SMP + extern void migrate_disable(void); + extern void migrate_enable(void); +# else /* CONFIG_SMP */ +# define migrate_disable() barrier() +# define migrate_enable() barrier() +# endif /* CONFIG_SMP */ +#else +# define preempt_disable_rt() barrier() +# define preempt_enable_rt() barrier() +# define preempt_disable_nort() preempt_disable() +# define preempt_enable_nort() preempt_enable() +# define migrate_disable() preempt_disable() +# define migrate_enable() preempt_enable() +#endif + #ifdef CONFIG_PREEMPT_NOTIFIERS struct preempt_notifier; Index: linux-3.12.19-rt30/include/linux/preempt_mask.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/preempt_mask.h +++ linux-3.12.19-rt30/include/linux/preempt_mask.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:61 @ #define HARDIRQ_OFFSET (1UL << HARDIRQ_SHIFT) #define NMI_OFFSET (1UL << NMI_SHIFT) -#define SOFTIRQ_DISABLE_OFFSET (2 * SOFTIRQ_OFFSET) +#ifndef CONFIG_PREEMPT_RT_FULL +# define SOFTIRQ_DISABLE_OFFSET (2 * SOFTIRQ_OFFSET) +#else +# define SOFTIRQ_DISABLE_OFFSET (0) +#endif #ifndef PREEMPT_ACTIVE #define PREEMPT_ACTIVE_BITS 1 @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:78 @ #endif #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)) +#ifndef CONFIG_PREEMPT_RT_FULL +# define softirq_count() (preempt_count() & SOFTIRQ_MASK) +# define in_serving_softirq() (softirq_count() & SOFTIRQ_OFFSET) +#else +# define softirq_count() (0UL) +extern int in_serving_softirq(void); +#endif /* * Are we doing bottom half or hardware interrupt processing? @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:97 @ #define in_irq() (hardirq_count()) #define in_softirq() (softirq_count()) #define in_interrupt() (irq_count()) -#define in_serving_softirq() (softirq_count() & SOFTIRQ_OFFSET) /* * Are we in NMI context? Index: linux-3.12.19-rt30/include/linux/printk.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/printk.h +++ linux-3.12.19-rt30/include/linux/printk.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:104 @ int no_printk(const char *fmt, ...) extern asmlinkage __printf(1, 2) void early_printk(const char *fmt, ...); void early_vprintk(const char *fmt, va_list ap); +extern void printk_kill(void); #else static inline __printf(1, 2) __cold void early_printk(const char *s, ...) { } +static inline void printk_kill(void) { } #endif #ifdef CONFIG_PRINTK @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:142 @ extern int __printk_ratelimit(const char #define printk_ratelimit() __printk_ratelimit(__func__) extern bool printk_timed_ratelimit(unsigned long *caller_jiffies, unsigned int interval_msec); - extern int printk_delay_msec; extern int dmesg_restrict; extern int kptr_restrict; Index: linux-3.12.19-rt30/include/linux/radix-tree.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/radix-tree.h +++ linux-3.12.19-rt30/include/linux/radix-tree.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:230 @ radix_tree_gang_lookup(struct radix_tree unsigned int radix_tree_gang_lookup_slot(struct radix_tree_root *root, void ***results, unsigned long *indices, unsigned long first_index, unsigned int max_items); +#ifndef CONFIG_PREEMPT_RT_FULL int radix_tree_preload(gfp_t gfp_mask); int radix_tree_maybe_preload(gfp_t gfp_mask); +#else +static inline int radix_tree_preload(gfp_t gm) { return 0; } +static inline int radix_tree_maybe_preload(gfp_t gfp_mask) { return 0; } +#endif void radix_tree_init(void); void *radix_tree_tag_set(struct radix_tree_root *root, unsigned long index, unsigned int tag); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:261 @ unsigned long radix_tree_locate_item(str static inline void radix_tree_preload_end(void) { - preempt_enable(); + preempt_enable_nort(); } /** Index: linux-3.12.19-rt30/include/linux/random.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/random.h +++ linux-3.12.19-rt30/include/linux/random.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:15 @ extern void add_device_randomness(const void *, unsigned int); extern void add_input_randomness(unsigned int type, unsigned int code, unsigned int value); -extern void add_interrupt_randomness(int irq, int irq_flags); +extern void add_interrupt_randomness(int irq, int irq_flags, __u64 ip); extern void get_random_bytes(void *buf, int nbytes); extern void get_random_bytes_arch(void *buf, int nbytes); Index: linux-3.12.19-rt30/include/linux/rcupdate.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/rcupdate.h +++ linux-3.12.19-rt30/include/linux/rcupdate.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:131 @ extern void call_rcu(struct rcu_head *he #endif /* #else #ifdef CONFIG_PREEMPT_RCU */ +#ifdef CONFIG_PREEMPT_RT_FULL +#define call_rcu_bh call_rcu +#else /** * call_rcu_bh() - Queue an RCU for invocation after a quicker grace period. * @head: structure to be used for queueing the RCU updates. @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:157 @ extern void call_rcu(struct rcu_head *he */ extern void call_rcu_bh(struct rcu_head *head, void (*func)(struct rcu_head *head)); +#endif /** * call_rcu_sched() - Queue an RCU for invocation after sched grace period. @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:197 @ void synchronize_rcu(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_FULL +#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 */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:225 @ 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 */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:376 @ static inline int rcu_read_lock_held(voi * rcu_read_lock_bh_held() is defined out of line to avoid #include-file * hell. */ +#ifdef CONFIG_PREEMPT_RT_FULL +static inline int rcu_read_lock_bh_held(void) +{ + return rcu_read_lock_held(); +} +#else extern int rcu_read_lock_bh_held(void); +#endif /** * rcu_read_lock_sched_held() - might we be in RCU-sched read-side critical section? @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:840 @ static inline void rcu_read_unlock(void) static inline void rcu_read_lock_bh(void) { local_bh_disable(); +#ifdef CONFIG_PREEMPT_RT_FULL + rcu_read_lock(); +#else __acquire(RCU_BH); rcu_lock_acquire(&rcu_bh_lock_map); rcu_lockdep_assert(!rcu_is_cpu_idle(), "rcu_read_lock_bh() used illegally while idle"); +#endif } /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:857 @ static inline void rcu_read_lock_bh(void */ static inline void rcu_read_unlock_bh(void) { +#ifdef CONFIG_PREEMPT_RT_FULL + rcu_read_unlock(); +#else rcu_lockdep_assert(!rcu_is_cpu_idle(), "rcu_read_unlock_bh() used illegally while idle"); rcu_lock_release(&rcu_bh_lock_map); __release(RCU_BH); +#endif local_bh_enable(); } Index: linux-3.12.19-rt30/include/linux/rcutree.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/rcutree.h +++ linux-3.12.19-rt30/include/linux/rcutree.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:47 @ static inline void rcu_virt_note_context rcu_note_context_switch(cpu); } +#ifdef CONFIG_PREEMPT_RT_FULL +# define synchronize_rcu_bh synchronize_rcu +#else extern void synchronize_rcu_bh(void); +#endif extern void synchronize_sched_expedited(void); extern void synchronize_rcu_expedited(void); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:79 @ static inline void synchronize_rcu_bh_ex } extern void rcu_barrier(void); +#ifdef CONFIG_PREEMPT_RT_FULL +# define rcu_barrier_bh rcu_barrier +#else extern void rcu_barrier_bh(void); +#endif extern void rcu_barrier_sched(void); extern unsigned long rcutorture_testseq; extern unsigned long rcutorture_vernum; extern long rcu_batches_completed(void); -extern long rcu_batches_completed_bh(void); extern long rcu_batches_completed_sched(void); extern void rcu_force_quiescent_state(void); -extern void rcu_bh_force_quiescent_state(void); extern void rcu_sched_force_quiescent_state(void); extern void exit_rcu(void); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:99 @ extern void exit_rcu(void); extern void rcu_scheduler_starting(void); extern int rcu_scheduler_active __read_mostly; +#ifndef CONFIG_PREEMPT_RT_FULL +extern void rcu_bh_force_quiescent_state(void); +extern long rcu_batches_completed_bh(void); +#else +# define rcu_bh_force_quiescent_state rcu_force_quiescent_state +# define rcu_batches_completed_bh rcu_batches_completed +#endif + #endif /* __LINUX_RCUTREE_H */ Index: linux-3.12.19-rt30/include/linux/rtmutex.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/rtmutex.h +++ linux-3.12.19-rt30/include/linux/rtmutex.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:17 @ #include <linux/linkage.h> #include <linux/plist.h> -#include <linux/spinlock_types.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 * @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:36 @ struct rt_mutex { raw_spinlock_t wait_lock; struct plist_head wait_list; struct task_struct *owner; -#ifdef CONFIG_DEBUG_RT_MUTEXES int save_state; - const char *name, *file; +#ifdef CONFIG_DEBUG_RT_MUTEXES + const char *file; + const char *name; int line; void *magic; #endif @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:64 @ struct hrtimer_sleeper; #ifdef CONFIG_DEBUG_RT_MUTEXES # define __DEBUG_RT_MUTEX_INITIALIZER(mutexname) \ , .name = #mutexname, .file = __FILE__, .line = __LINE__ -# define rt_mutex_init(mutex) __rt_mutex_init(mutex, __func__) + +# define rt_mutex_init(mutex) \ + do { \ + raw_spin_lock_init(&(mutex)->wait_lock); \ + __rt_mutex_init(mutex, #mutex); \ + } 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) + +# define rt_mutex_init(mutex) \ + do { \ + raw_spin_lock_init(&(mutex)->wait_lock); \ + __rt_mutex_init(mutex, #mutex); \ + } while (0) + # define rt_mutex_debug_task_free(t) do { } while (0) #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) \ , .wait_list = PLIST_HEAD_INIT(mutexname.wait_list) \ , .owner = NULL \ - __DEBUG_RT_MUTEX_INITIALIZER(mutexname)} + __DEBUG_RT_MUTEX_INITIALIZER(mutexname) + + +#define __RT_MUTEX_INITIALIZER(mutexname) \ + { __RT_MUTEX_INITIALIZER_PLAIN(mutexname) } + +#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) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:118 @ extern void rt_mutex_destroy(struct rt_m extern void rt_mutex_lock(struct rt_mutex *lock); extern int rt_mutex_lock_interruptible(struct rt_mutex *lock, int detect_deadlock); +extern int rt_mutex_lock_killable(struct rt_mutex *lock, int detect_deadlock); extern int rt_mutex_timed_lock(struct rt_mutex *lock, struct hrtimer_sleeper *timeout, int detect_deadlock); Index: linux-3.12.19-rt30/include/linux/rwlock_rt.h =================================================================== --- /dev/null +++ linux-3.12.19-rt30/include/linux/rwlock_rt.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:4 @ +#ifndef __LINUX_RWLOCK_RT_H +#define __LINUX_RWLOCK_RT_H + +#ifndef __LINUX_SPINLOCK_H +#error Do not include directly. Use spinlock.h +#endif + +#define rwlock_init(rwl) \ +do { \ + static struct lock_class_key __key; \ + \ + rt_mutex_init(&(rwl)->lock); \ + __rt_rwlock_init(rwl, #rwl, &__key); \ +} while (0) + +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_write_trylock_irqsave(rwlock_t *trylock, unsigned long *flags); +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 unsigned long __lockfunc rt_write_lock_irqsave(rwlock_t *rwlock); +extern unsigned long __lockfunc rt_read_lock_irqsave(rwlock_t *rwlock); +extern void __rt_rwlock_init(rwlock_t *rwlock, char *name, struct lock_class_key *key); + +#define read_trylock(lock) __cond_lock(lock, rt_read_trylock(lock)) +#define write_trylock(lock) __cond_lock(lock, rt_write_trylock(lock)) + +#define write_trylock_irqsave(lock, flags) \ + __cond_lock(lock, rt_write_trylock_irqsave(lock, &flags)) + +#define read_lock_irqsave(lock, flags) \ + do { \ + typecheck(unsigned long, flags); \ + flags = rt_read_lock_irqsave(lock); \ + } while (0) + +#define write_lock_irqsave(lock, flags) \ + do { \ + typecheck(unsigned long, flags); \ + flags = rt_write_lock_irqsave(lock); \ + } 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) + +#endif Index: linux-3.12.19-rt30/include/linux/rwlock_types.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/rwlock_types.h +++ linux-3.12.19-rt30/include/linux/rwlock_types.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt: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 @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:50 @ typedef struct { RW_DEP_MAP_INIT(lockname) } #endif -#define DEFINE_RWLOCK(x) rwlock_t x = __RW_LOCK_UNLOCKED(x) +#define DEFINE_RWLOCK(name) \ + rwlock_t name __cacheline_aligned_in_smp = __RW_LOCK_UNLOCKED(name) #endif /* __LINUX_RWLOCK_TYPES_H */ Index: linux-3.12.19-rt30/include/linux/rwlock_types_rt.h =================================================================== --- /dev/null +++ linux-3.12.19-rt30/include/linux/rwlock_types_rt.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:4 @ +#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 + +/* + * rwlocks - rtmutex which allows single reader recursion + */ +typedef struct { + struct rt_mutex lock; + int read_depth; + unsigned int break_lock; +#ifdef CONFIG_DEBUG_LOCK_ALLOC + struct lockdep_map dep_map; +#endif +} rwlock_t; + +#ifdef CONFIG_DEBUG_LOCK_ALLOC +# define RW_DEP_MAP_INIT(lockname) .dep_map = { .name = #lockname } +#else +# define RW_DEP_MAP_INIT(lockname) +#endif + +#define __RW_LOCK_UNLOCKED(name) \ + { .lock = __RT_MUTEX_INITIALIZER_SAVE_STATE(name.lock), \ + RW_DEP_MAP_INIT(name) } + +#define DEFINE_RWLOCK(name) \ + rwlock_t name __cacheline_aligned_in_smp = __RW_LOCK_UNLOCKED(name) + +#endif Index: linux-3.12.19-rt30/include/linux/rwsem.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/rwsem.h +++ linux-3.12.19-rt30/include/linux/rwsem.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:19 @ #include <linux/atomic.h> +#ifdef CONFIG_PREEMPT_RT_FULL +#include <linux/rwsem_rt.h> +#else /* PREEMPT_RT_FULL */ + struct rw_semaphore; #ifdef CONFIG_RWSEM_GENERIC_SPINLOCK @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:156 @ extern void up_read_non_owner(struct rw_ # define up_read_non_owner(sem) up_read(sem) #endif +#endif /* !PREEMPT_RT_FULL */ + #endif /* _LINUX_RWSEM_H */ Index: linux-3.12.19-rt30/include/linux/rwsem_rt.h =================================================================== --- /dev/null +++ linux-3.12.19-rt30/include/linux/rwsem_rt.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:4 @ +#ifndef _LINUX_RWSEM_RT_H +#define _LINUX_RWSEM_RT_H + +#ifndef _LINUX_RWSEM_H +#error "Include rwsem.h" +#endif + +/* + * RW-semaphores are a spinlock plus a reader-depth count. + * + * Note that the semantics are different from the usual + * Linux rw-sems, in PREEMPT_RT mode we do not allow + * multiple readers to hold the lock at once, we only allow + * a read-lock owner to read-lock recursively. This is + * better for latency, makes the implementation inherently + * fair and makes it simpler as well. + */ + +#include <linux/rtmutex.h> + +struct rw_semaphore { + struct rt_mutex lock; + int read_depth; +#ifdef CONFIG_DEBUG_LOCK_ALLOC + struct lockdep_map dep_map; +#endif +}; + +#define __RWSEM_INITIALIZER(name) \ + { .lock = __RT_MUTEX_INITIALIZER(name.lock), \ + RW_DEP_MAP_INIT(name) } + +#define DECLARE_RWSEM(lockname) \ + struct rw_semaphore lockname = __RWSEM_INITIALIZER(lockname) + +extern void __rt_rwsem_init(struct rw_semaphore *rwsem, const char *name, + struct lock_class_key *key); + +#define __rt_init_rwsem(sem, name, key) \ + do { \ + rt_mutex_init(&(sem)->lock); \ + __rt_rwsem_init((sem), (name), (key));\ + } while (0) + +#define __init_rwsem(sem, name, key) __rt_init_rwsem(sem, name, key) + +# define rt_init_rwsem(sem) \ +do { \ + static struct lock_class_key __key; \ + \ + __rt_init_rwsem((sem), #sem, &__key); \ +} while (0) + +extern void rt_down_write(struct rw_semaphore *rwsem); +extern void rt_down_read_nested(struct rw_semaphore *rwsem, int subclass); +extern void rt_down_write_nested(struct rw_semaphore *rwsem, int subclass); +extern void rt_down_write_nested_lock(struct rw_semaphore *rwsem, + struct lockdep_map *nest); +extern void rt_down_read(struct rw_semaphore *rwsem); +extern int rt_down_write_trylock(struct rw_semaphore *rwsem); +extern int rt_down_read_trylock(struct rw_semaphore *rwsem); +extern void rt_up_read(struct rw_semaphore *rwsem); +extern void rt_up_write(struct rw_semaphore *rwsem); +extern void rt_downgrade_write(struct rw_semaphore *rwsem); + +#define init_rwsem(sem) rt_init_rwsem(sem) +#define rwsem_is_locked(s) rt_mutex_is_locked(&(s)->lock) + +static inline void down_read(struct rw_semaphore *sem) +{ + rt_down_read(sem); +} + +static inline int down_read_trylock(struct rw_semaphore *sem) +{ + return rt_down_read_trylock(sem); +} + +static inline void down_write(struct rw_semaphore *sem) +{ + rt_down_write(sem); +} + +static inline int down_write_trylock(struct rw_semaphore *sem) +{ + return rt_down_write_trylock(sem); +} + +static inline void up_read(struct rw_semaphore *sem) +{ + rt_up_read(sem); +} + +static inline void up_write(struct rw_semaphore *sem) +{ + rt_up_write(sem); +} + +static inline void downgrade_write(struct rw_semaphore *sem) +{ + rt_downgrade_write(sem); +} + +static inline void down_read_nested(struct rw_semaphore *sem, int subclass) +{ + return rt_down_read_nested(sem, subclass); +} + +static inline void down_write_nested(struct rw_semaphore *sem, int subclass) +{ + rt_down_write_nested(sem, subclass); +} +#ifdef CONFIG_DEBUG_LOCK_ALLOC +static inline void down_write_nest_lock(struct rw_semaphore *sem, + struct rw_semaphore *nest_lock) +{ + rt_down_write_nested_lock(sem, &nest_lock->dep_map); +} + +#else + +static inline void down_write_nest_lock(struct rw_semaphore *sem, + struct rw_semaphore *nest_lock) +{ + rt_down_write_nested_lock(sem, NULL); +} +#endif +#endif Index: linux-3.12.19-rt30/include/linux/sched.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/sched.h +++ linux-3.12.19-rt30/include/linux/sched.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:26 @ struct sched_param { #include <linux/nodemask.h> #include <linux/mm_types.h> +#include <asm/kmap_types.h> #include <asm/page.h> #include <asm/ptrace.h> #include <asm/cputime.h> @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:56 @ struct sched_param { #include <linux/llist.h> #include <linux/uidgid.h> #include <linux/gfp.h> +#include <linux/hardirq.h> #include <asm/processor.h> @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:174 @ extern char ___assert_task_state[1 - 2*! TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \ __TASK_TRACED) -#define task_is_traced(task) ((task->state & __TASK_TRACED) != 0) #define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0) #define task_is_dead(task) ((task)->exit_state != 0) -#define task_is_stopped_or_traced(task) \ - ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0) #define task_contributes_to_load(task) \ ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \ (task->flags & PF_FROZEN) == 0) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1029 @ enum perf_event_task_context { struct task_struct { volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */ + volatile long saved_state; /* saved state for "spinlock sleepers" */ void *stack; atomic_t usage; unsigned int flags; /* per process flags, defined below */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1072 @ struct task_struct { #endif unsigned int policy; +#ifdef CONFIG_PREEMPT_RT_FULL + int migrate_disable; +# ifdef CONFIG_SCHED_DEBUG + int migrate_disable_atomic; +# endif +#endif int nr_cpus_allowed; cpumask_t cpus_allowed; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1177 @ struct task_struct { struct cputime prev_cputime; #endif #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN - seqlock_t vtime_seqlock; + raw_spinlock_t vtime_lock; + seqcount_t vtime_seq; unsigned long long vtime_snap; enum { VTIME_SLEEPING = 0, @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1194 @ struct task_struct { struct task_cputime cputime_expires; struct list_head cpu_timers[3]; +#ifdef CONFIG_PREEMPT_RT_BASE + struct task_struct *posix_timer_list; +#endif /* process credentials */ const struct cred __rcu *real_cred; /* objective and real subjective task @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1228 @ struct task_struct { /* signal handlers */ struct signal_struct *signal; struct sighand_struct *sighand; + struct sigqueue *sigqueue_cache; sigset_t blocked, real_blocked; sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */ struct sigpending pending; +#ifdef CONFIG_PREEMPT_RT_FULL + /* TODO: move me into ->restart_block ? */ + struct siginfo forced_info; +#endif unsigned long sas_ss_sp; size_t sas_ss_size; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1273 @ struct task_struct { /* mutex deadlock detection */ struct mutex_waiter *blocked_on; #endif +#ifdef CONFIG_PREEMPT_RT_FULL + int pagefault_disabled; +#endif #ifdef CONFIG_TRACE_IRQFLAGS unsigned int irq_events; unsigned long hardirq_enable_ip; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1351 @ struct task_struct { struct mutex perf_event_mutex; struct list_head perf_event_list; #endif +#ifdef CONFIG_DEBUG_PREEMPT + unsigned long preempt_disable_ip; +#endif #ifdef CONFIG_NUMA struct mempolicy *mempolicy; /* Protected by alloc_lock */ short il_next; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1421 @ struct task_struct { unsigned long trace; /* bitmask and counter of trace recursion */ unsigned long trace_recursion; +#ifdef CONFIG_WAKEUP_LATENCY_HIST + u64 preempt_timestamp_hist; +#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST + long timer_offset; +#endif +#endif #endif /* CONFIG_TRACING */ #ifdef CONFIG_MEMCG /* memcg uses this to do batch job */ struct memcg_batch_info { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1450 @ struct task_struct { unsigned int sequential_io; unsigned int sequential_io_avg; #endif +#ifdef CONFIG_PREEMPT_RT_BASE + struct rcu_head put_rcu; + int softirq_nestcnt; + unsigned int softirqs_raised; +#endif +#ifdef CONFIG_PREEMPT_RT_FULL +# if defined CONFIG_HIGHMEM || defined CONFIG_X86_32 + int kmap_idx; + pte_t kmap_pte[KM_TYPE_NR]; +# endif +#endif }; -/* Future-safe accessor for struct task_struct's cpus_allowed. */ -#define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed) - #ifdef CONFIG_NUMA_BALANCING extern void task_numa_fault(int node, int pages, bool migrated); extern void set_numabalancing_state(bool enabled); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1475 @ static inline void set_numabalancing_sta } #endif +#ifdef CONFIG_PREEMPT_RT_FULL +static inline bool cur_pf_disabled(void) { return current->pagefault_disabled; } +#else +static inline bool cur_pf_disabled(void) { return false; } +#endif + +static inline bool pagefault_disabled(void) +{ + return in_atomic() || cur_pf_disabled(); +} + static inline struct pid *task_pid(struct task_struct *task) { return task->pids[PIDTYPE_PID].pid; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1639 @ extern struct pid *cad_pid; extern void free_task(struct task_struct *tsk); #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0) +#ifdef CONFIG_PREEMPT_RT_BASE +extern void __put_task_struct_cb(struct rcu_head *rhp); + +static inline void put_task_struct(struct task_struct *t) +{ + if (atomic_dec_and_test(&t->usage)) + call_rcu(&t->put_rcu, __put_task_struct_cb); +} +#else extern void __put_task_struct(struct task_struct *t); static inline void put_task_struct(struct task_struct *t) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1655 @ static inline void put_task_struct(struc if (atomic_dec_and_test(&t->usage)) __put_task_struct(t); } +#endif #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN extern void task_cputime(struct task_struct *t, @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1694 @ extern void thread_group_cputime_adjuste /* * Per process flags */ +#define PF_IN_SOFTIRQ 0x00000001 /* Task is serving softirq */ #define PF_EXITING 0x00000004 /* getting shut down */ #define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */ #define PF_VCPU 0x00000010 /* I'm a virtual CPU */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1840 @ extern void do_set_cpus_allowed(struct t extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask); +int migrate_me(void); +void tell_sched_cpu_down_begin(int cpu); +void tell_sched_cpu_down_done(int cpu); + #else static inline void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1856 @ static inline int set_cpus_allowed_ptr(s return -EINVAL; return 0; } +static inline int migrate_me(void) { return 0; } +static inline void tell_sched_cpu_down_begin(int cpu) { } +static inline void tell_sched_cpu_down_done(int cpu) { } #endif #ifdef CONFIG_NO_HZ_COMMON @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2066 @ extern void xtime_update(unsigned long t 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 extern void kick_process(struct task_struct *tsk); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2181 @ extern struct mm_struct * mm_alloc(void) /* mmdrop drops the mm and the page tables */ extern void __mmdrop(struct mm_struct *); + static inline void mmdrop(struct mm_struct * mm) { if (unlikely(atomic_dec_and_test(&mm->mm_count))) __mmdrop(mm); } +#ifdef CONFIG_PREEMPT_RT_BASE +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 + /* mmput gets rid of the mappings and all user-space */ extern void mmput(struct mm_struct *); /* Grab a reference to a task's mm, if it is not already going away */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2491 @ static inline int test_tsk_need_resched( 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); +} + +static inline int need_resched(void) +{ + return test_thread_flag(TIF_NEED_RESCHED) || + test_thread_flag(TIF_NEED_RESCHED_LAZY); +} +#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); +} + +static inline int need_resched(void) +{ + return test_thread_flag(TIF_NEED_RESCHED); +} +#endif + static inline int restart_syscall(void) { set_tsk_thread_flag(current, TIF_SIGPENDING); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2568 @ static inline int signal_pending_state(l return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p); } -static inline int need_resched(void) +static inline bool __task_is_stopped_or_traced(struct task_struct *task) { - return unlikely(test_thread_flag(TIF_NEED_RESCHED)); + if (task->state & (__TASK_STOPPED | __TASK_TRACED)) + return true; +#ifdef CONFIG_PREEMPT_RT_FULL + 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_FULL + 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_FULL + /* 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; } /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2629 @ extern int _cond_resched(void); extern int __cond_resched_lock(spinlock_t *lock); -#ifdef CONFIG_PREEMPT_COUNT +#if defined(CONFIG_PREEMPT_COUNT) && !defined(CONFIG_PREEMPT_RT_FULL) #define PREEMPT_LOCK_OFFSET PREEMPT_OFFSET #else #define PREEMPT_LOCK_OFFSET 0 @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2640 @ extern int __cond_resched_lock(spinlock_ __cond_resched_lock(lock); \ }) +#ifndef CONFIG_PREEMPT_RT_FULL extern int __cond_resched_softirq(void); #define cond_resched_softirq() ({ \ __might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \ __cond_resched_softirq(); \ }) +#else +# define cond_resched_softirq() cond_resched() +#endif static inline void cond_resched_rcu(void) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2835 @ static inline void set_task_cpu(struct t #endif /* CONFIG_SMP */ +static inline int __migrate_disabled(struct task_struct *p) +{ +#ifdef CONFIG_PREEMPT_RT_FULL + return p->migrate_disable; +#else + return 0; +#endif +} + +/* Future-safe accessor for struct task_struct's cpus_allowed. */ +static inline const struct cpumask *tsk_cpus_allowed(struct task_struct *p) +{ +#ifdef CONFIG_PREEMPT_RT_FULL + if (p->migrate_disable) + return cpumask_of(task_cpu(p)); +#endif + + return &p->cpus_allowed; +} + extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); extern long sched_getaffinity(pid_t pid, struct cpumask *mask); Index: linux-3.12.19-rt30/include/linux/sched/rt.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/sched/rt.h +++ linux-3.12.19-rt30/include/linux/sched/rt.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:38 @ static inline int rt_task(struct task_st #ifdef CONFIG_RT_MUTEXES extern int rt_mutex_getprio(struct task_struct *p); extern void rt_mutex_setprio(struct task_struct *p, int prio); +extern int rt_mutex_check_prio(struct task_struct *task, int newprio); extern void rt_mutex_adjust_pi(struct task_struct *p); static inline bool tsk_is_pi_blocked(struct task_struct *tsk) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:49 @ static inline int rt_mutex_getprio(struc { return p->normal_prio; } +static inline int rt_mutex_check_prio(struct task_struct *task, int newprio) +{ + return 0; +} # define rt_mutex_adjust_pi(p) do { } while (0) static inline bool tsk_is_pi_blocked(struct task_struct *tsk) { Index: linux-3.12.19-rt30/include/linux/seqlock.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/seqlock.h +++ linux-3.12.19-rt30/include/linux/seqlock.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:155 @ static inline int read_seqcount_retry(co * Sequence counter only version assumes that callers are using their * own mutexing. */ -static inline void write_seqcount_begin(seqcount_t *s) +static inline void __write_seqcount_begin(seqcount_t *s) { s->sequence++; smp_wmb(); } -static inline void write_seqcount_end(seqcount_t *s) +static inline void write_seqcount_begin(seqcount_t *s) +{ + preempt_disable_rt(); + __write_seqcount_begin(s); +} + +static inline void __write_seqcount_end(seqcount_t *s) { smp_wmb(); s->sequence++; } +static inline void write_seqcount_end(seqcount_t *s) +{ + __write_seqcount_end(s); + preempt_enable_rt(); +} + /** * write_seqcount_barrier - invalidate in-progress read-side seq operations * @s: pointer to seqcount_t @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:219 @ typedef struct { /* * Read side functions for starting and finalizing a read side section. */ +#ifndef CONFIG_PREEMPT_RT_FULL static inline unsigned read_seqbegin(const seqlock_t *sl) { return read_seqcount_begin(&sl->seqcount); } +#else +/* + * Starvation safe read side for RT + */ +static inline unsigned read_seqbegin(seqlock_t *sl) +{ + unsigned ret; + +repeat: + ret = ACCESS_ONCE(sl->seqcount.sequence); + if (unlikely(ret & 1)) { + /* + * Take the lock and let the writer proceed (i.e. evtl + * boost it), otherwise we could loop here forever. + */ + spin_unlock_wait(&sl->lock); + goto repeat; + } + return ret; +} +#endif static inline unsigned read_seqretry(const seqlock_t *sl, unsigned start) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:259 @ static inline unsigned read_seqretry(con static inline void write_seqlock(seqlock_t *sl) { spin_lock(&sl->lock); - write_seqcount_begin(&sl->seqcount); + __write_seqcount_begin(&sl->seqcount); } static inline void write_sequnlock(seqlock_t *sl) { - write_seqcount_end(&sl->seqcount); + __write_seqcount_end(&sl->seqcount); spin_unlock(&sl->lock); } static inline void write_seqlock_bh(seqlock_t *sl) { spin_lock_bh(&sl->lock); - write_seqcount_begin(&sl->seqcount); + __write_seqcount_begin(&sl->seqcount); } static inline void write_sequnlock_bh(seqlock_t *sl) { - write_seqcount_end(&sl->seqcount); + __write_seqcount_end(&sl->seqcount); spin_unlock_bh(&sl->lock); } static inline void write_seqlock_irq(seqlock_t *sl) { spin_lock_irq(&sl->lock); - write_seqcount_begin(&sl->seqcount); + __write_seqcount_begin(&sl->seqcount); } static inline void write_sequnlock_irq(seqlock_t *sl) { - write_seqcount_end(&sl->seqcount); + __write_seqcount_end(&sl->seqcount); spin_unlock_irq(&sl->lock); } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:297 @ static inline unsigned long __write_seql unsigned long flags; spin_lock_irqsave(&sl->lock, flags); - write_seqcount_begin(&sl->seqcount); + __write_seqcount_begin(&sl->seqcount); return flags; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:307 @ static inline unsigned long __write_seql static inline void write_sequnlock_irqrestore(seqlock_t *sl, unsigned long flags) { - write_seqcount_end(&sl->seqcount); + __write_seqcount_end(&sl->seqcount); spin_unlock_irqrestore(&sl->lock, flags); } Index: linux-3.12.19-rt30/include/linux/signal.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/signal.h +++ linux-3.12.19-rt30/include/linux/signal.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:229 @ static inline void init_sigpending(struc } 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) Index: linux-3.12.19-rt30/include/linux/skbuff.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/skbuff.h +++ linux-3.12.19-rt30/include/linux/skbuff.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:136 @ struct sk_buff_head { __u32 qlen; spinlock_t lock; + raw_spinlock_t raw_lock; }; struct sk_buff; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1077 @ static inline void skb_queue_head_init(s __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) { Index: linux-3.12.19-rt30/include/linux/smp.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/smp.h +++ linux-3.12.19-rt30/include/linux/smp.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:191 @ static inline void __smp_call_function_s #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: Index: linux-3.12.19-rt30/include/linux/spinlock.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/spinlock.h +++ linux-3.12.19-rt30/include/linux/spinlock.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:265 @ static inline void do_raw_spin_unlock(ra #define raw_spin_can_lock(lock) (!raw_spin_is_locked(lock)) /* Include rwlock functions */ -#include <linux/rwlock.h> +#ifdef CONFIG_PREEMPT_RT_FULL +# include <linux/rwlock_rt.h> +#else +# include <linux/rwlock.h> +#endif /* * Pull the _spin_*()/_read_*()/_write_*() functions/declarations: @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:280 @ static inline void do_raw_spin_unlock(ra # include <linux/spinlock_api_up.h> #endif +#ifdef CONFIG_PREEMPT_RT_FULL +# include <linux/spinlock_rt.h> +#else /* PREEMPT_RT_FULL */ + /* * Map the spin_lock functions to the raw variants for PREEMPT_RT=n */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:413 @ extern int _atomic_dec_and_lock(atomic_t #define atomic_dec_and_lock(atomic, lock) \ __cond_lock(lock, _atomic_dec_and_lock(atomic, lock)) +#endif /* !PREEMPT_RT_FULL */ + #endif /* __LINUX_SPINLOCK_H */ Index: linux-3.12.19-rt30/include/linux/spinlock_api_smp.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/spinlock_api_smp.h +++ linux-3.12.19-rt30/include/linux/spinlock_api_smp.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:194 @ static inline int __raw_spin_trylock_bh( return 0; } -#include <linux/rwlock_api_smp.h> +#ifndef CONFIG_PREEMPT_RT_FULL +# include <linux/rwlock_api_smp.h> +#endif #endif /* __LINUX_SPINLOCK_API_SMP_H */ Index: linux-3.12.19-rt30/include/linux/spinlock_rt.h =================================================================== --- /dev/null +++ linux-3.12.19-rt30/include/linux/spinlock_rt.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:4 @ +#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, 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 unsigned long __lockfunc rt_spin_lock_trace_flags(spinlock_t *lock); +extern void __lockfunc rt_spin_lock_nested(spinlock_t *lock, int subclass); +extern void __lockfunc rt_spin_unlock(spinlock_t *lock); +extern void __lockfunc rt_spin_unlock_after_trylock_in_irq(spinlock_t *lock); +extern void __lockfunc rt_spin_unlock_wait(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. + */ +extern void __lockfunc __rt_spin_lock(struct rt_mutex *lock); +extern void __lockfunc __rt_spin_unlock(struct rt_mutex *lock); + +#define spin_lock(lock) \ + do { \ + migrate_disable(); \ + rt_spin_lock(lock); \ + } while (0) + +#define spin_lock_bh(lock) \ + do { \ + local_bh_disable(); \ + migrate_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; \ + migrate_disable(); \ + __locked = spin_do_trylock(lock); \ + if (!__locked) \ + migrate_enable(); \ + __locked; \ +}) + +#ifdef CONFIG_LOCKDEP +# define spin_lock_nested(lock, subclass) \ + do { \ + migrate_disable(); \ + rt_spin_lock_nested(lock, subclass); \ + } while (0) + +# define spin_lock_irqsave_nested(lock, flags, subclass) \ + do { \ + typecheck(unsigned long, flags); \ + flags = 0; \ + migrate_disable(); \ + rt_spin_lock_nested(lock, subclass); \ + } while (0) +#else +# define spin_lock_nested(lock, subclass) spin_lock(lock) + +# define spin_lock_irqsave_nested(lock, flags, subclass) \ + do { \ + typecheck(unsigned long, flags); \ + flags = 0; \ + spin_lock(lock); \ + } while (0) +#endif + +#define spin_lock_irqsave(lock, flags) \ + do { \ + typecheck(unsigned long, flags); \ + flags = 0; \ + spin_lock(lock); \ + } while (0) + +static inline unsigned long spin_lock_trace_flags(spinlock_t *lock) +{ + unsigned long flags = 0; +#ifdef CONFIG_TRACE_IRQFLAGS + flags = rt_spin_lock_trace_flags(lock); +#else + spin_lock(lock); /* lock_local */ +#endif + return flags; +} + +/* FIXME: we need rt_spin_lock_nest_lock */ +#define spin_lock_nest_lock(lock, nest_lock) spin_lock_nested(lock, 0) + +#define spin_unlock(lock) \ + do { \ + rt_spin_unlock(lock); \ + migrate_enable(); \ + } while (0) + +#define spin_unlock_bh(lock) \ + do { \ + rt_spin_unlock(lock); \ + migrate_enable(); \ + 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) \ + rt_spin_trylock_irqsave(lock, &(flags)) + +#define spin_unlock_wait(lock) rt_spin_unlock_wait(lock) + +#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)); +} + +#define atomic_dec_and_lock(atomic, lock) \ + atomic_dec_and_spin_lock(atomic, lock) + +#endif Index: linux-3.12.19-rt30/include/linux/spinlock_types.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/spinlock_types.h +++ linux-3.12.19-rt30/include/linux/spinlock_types.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt: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.h> - -typedef struct raw_spinlock { - arch_spinlock_t raw_lock; -#ifdef CONFIG_GENERIC_LOCKBREAK - unsigned int break_lock; -#endif -#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 SPIN_DEP_MAP_INIT(lockname) .dep_map = { .name = #lockname } -#else -# 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_FULL +# 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) \ - 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) \ - { { .rlock = __RAW_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 */ Index: linux-3.12.19-rt30/include/linux/spinlock_types_nort.h =================================================================== --- /dev/null +++ linux-3.12.19-rt30/include/linux/spinlock_types_nort.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt: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) \ + { { .rlock = __RAW_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 Index: linux-3.12.19-rt30/include/linux/spinlock_types_raw.h =================================================================== --- /dev/null +++ linux-3.12.19-rt30/include/linux/spinlock_types_raw.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:4 @ +#ifndef __LINUX_SPINLOCK_TYPES_RAW_H +#define __LINUX_SPINLOCK_TYPES_RAW_H + +#if defined(CONFIG_SMP) +# include <asm/spinlock_types.h> +#else +# include <linux/spinlock_types_up.h> +#endif + +#include <linux/lockdep.h> + +typedef struct raw_spinlock { + arch_spinlock_t raw_lock; +#ifdef CONFIG_GENERIC_LOCKBREAK + unsigned int break_lock; +#endif +#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 SPIN_DEP_MAP_INIT(lockname) .dep_map = { .name = #lockname } +#else +# 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) \ + 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 Index: linux-3.12.19-rt30/include/linux/spinlock_types_rt.h =================================================================== --- /dev/null +++ linux-3.12.19-rt30/include/linux/spinlock_types_rt.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:4 @ +#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; + +#ifdef CONFIG_DEBUG_RT_MUTEXES +# define __RT_SPIN_INITIALIZER(name) \ + { \ + .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(name.wait_lock), \ + .save_state = 1, \ + .file = __FILE__, \ + .line = __LINE__ , \ + } +#else +# define __RT_SPIN_INITIALIZER(name) \ + { \ + .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(name.wait_lock), \ + .save_state = 1, \ + } +#endif + +/* +.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) + +#define DEFINE_SPINLOCK(name) \ + spinlock_t name __cacheline_aligned_in_smp = __SPIN_LOCK_UNLOCKED(name) + +#endif Index: linux-3.12.19-rt30/include/linux/srcu.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/srcu.h +++ linux-3.12.19-rt30/include/linux/srcu.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:87 @ int init_srcu_struct(struct srcu_struct void process_srcu(struct work_struct *work); -#define __SRCU_STRUCT_INIT(name) \ +#define __SRCU_STRUCT_INIT(name, pcpu_name) \ { \ .completed = -300, \ - .per_cpu_ref = &name##_srcu_array, \ + .per_cpu_ref = &pcpu_name, \ .queue_lock = __SPIN_LOCK_UNLOCKED(name.queue_lock), \ .running = false, \ .batch_queue = RCU_BATCH_INIT(name.batch_queue), \ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:107 @ void process_srcu(struct work_struct *wo */ #define DEFINE_SRCU(name) \ static DEFINE_PER_CPU(struct srcu_struct_array, name##_srcu_array);\ - struct srcu_struct name = __SRCU_STRUCT_INIT(name); + struct srcu_struct name = __SRCU_STRUCT_INIT(name, name##_srcu_array); #define DEFINE_STATIC_SRCU(name) \ static DEFINE_PER_CPU(struct srcu_struct_array, name##_srcu_array);\ - static struct srcu_struct name = __SRCU_STRUCT_INIT(name); + static struct srcu_struct name = __SRCU_STRUCT_INIT(\ + name, name##_srcu_array); /** * call_srcu() - Queue a callback for invocation after an SRCU grace period Index: linux-3.12.19-rt30/include/linux/sysctl.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/sysctl.h +++ linux-3.12.19-rt30/include/linux/sysctl.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:28 @ #include <linux/rcupdate.h> #include <linux/wait.h> #include <linux/rbtree.h> +#include <linux/atomic.h> #include <uapi/linux/sysctl.h> /* For the /proc/sys support */ Index: linux-3.12.19-rt30/include/linux/timer.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/timer.h +++ linux-3.12.19-rt30/include/linux/timer.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:244 @ extern void add_timer(struct timer_list extern int try_to_del_timer_sync(struct timer_list *timer); -#ifdef CONFIG_SMP +#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT_FULL) extern int del_timer_sync(struct timer_list *timer); #else # define del_timer_sync(t) del_timer(t) Index: linux-3.12.19-rt30/include/linux/uaccess.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/uaccess.h +++ linux-3.12.19-rt30/include/linux/uaccess.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:9 @ /* * These routines enable/disable the pagefault handler in that - * it will not take any locks and go straight to the fixup table. - * - * They have great resemblance to the preempt_disable/enable calls - * and in fact they are identical; this is because currently there is - * no other way to make the pagefault handlers do this. So we do - * disable preemption but we don't necessarily care about that. + * it will not take any MM locks and go straight to the fixup table. */ -static inline void pagefault_disable(void) +static inline void raw_pagefault_disable(void) { inc_preempt_count(); - /* - * make sure to have issued the store before a pagefault - * can hit. - */ barrier(); } -static inline void pagefault_enable(void) +static inline void raw_pagefault_enable(void) { - /* - * make sure to issue those last loads/stores before enabling - * the pagefault handler again. - */ barrier(); dec_preempt_count(); - /* - * make sure we do.. - */ barrier(); preempt_check_resched(); } +#ifndef CONFIG_PREEMPT_RT_FULL +static inline void pagefault_disable(void) +{ + raw_pagefault_disable(); +} + +static inline void pagefault_enable(void) +{ + raw_pagefault_enable(); +} +#else +extern void pagefault_disable(void); +extern void pagefault_enable(void); +#endif + #ifndef ARCH_HAS_NOCACHE_UACCESS static inline unsigned long __copy_from_user_inatomic_nocache(void *to, @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:79 @ static inline unsigned long __copy_from_ mm_segment_t old_fs = get_fs(); \ \ set_fs(KERNEL_DS); \ - pagefault_disable(); \ + raw_pagefault_disable(); \ ret = __copy_from_user_inatomic(&(retval), (__force typeof(retval) __user *)(addr), sizeof(retval)); \ - pagefault_enable(); \ + raw_pagefault_enable(); \ set_fs(old_fs); \ ret; \ }) Index: linux-3.12.19-rt30/include/linux/uprobes.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/uprobes.h +++ linux-3.12.19-rt30/include/linux/uprobes.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:29 @ #include <linux/errno.h> #include <linux/rbtree.h> +#include <linux/wait.h> struct vm_area_struct; struct mm_struct; Index: linux-3.12.19-rt30/include/linux/vmstat.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/vmstat.h +++ linux-3.12.19-rt30/include/linux/vmstat.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:32 @ DECLARE_PER_CPU(struct vm_event_state, v static inline void __count_vm_event(enum vm_event_item item) { + preempt_disable_rt(); __this_cpu_inc(vm_event_states.event[item]); + preempt_enable_rt(); } static inline void count_vm_event(enum vm_event_item item) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:44 @ static inline void count_vm_event(enum v static inline void __count_vm_events(enum vm_event_item item, long delta) { + preempt_disable_rt(); __this_cpu_add(vm_event_states.event[item], delta); + preempt_enable_rt(); } static inline void count_vm_events(enum vm_event_item item, long delta) Index: linux-3.12.19-rt30/include/linux/wait-simple.h =================================================================== --- /dev/null +++ linux-3.12.19-rt30/include/linux/wait-simple.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:4 @ +#ifndef _LINUX_WAIT_SIMPLE_H +#define _LINUX_WAIT_SIMPLE_H + +#include <linux/spinlock.h> +#include <linux/list.h> + +#include <asm/current.h> + +struct swaiter { + struct task_struct *task; + struct list_head node; +}; + +#define DEFINE_SWAITER(name) \ + struct swaiter name = { \ + .task = current, \ + .node = LIST_HEAD_INIT((name).node), \ + } + +struct swait_head { + raw_spinlock_t lock; + struct list_head list; +}; + +#define SWAIT_HEAD_INITIALIZER(name) { \ + .lock = __RAW_SPIN_LOCK_UNLOCKED(name.lock), \ + .list = LIST_HEAD_INIT((name).list), \ + } + +#define DEFINE_SWAIT_HEAD(name) \ + struct swait_head name = SWAIT_HEAD_INITIALIZER(name) + +extern void __init_swait_head(struct swait_head *h, struct lock_class_key *key); + +#define init_swait_head(swh) \ + do { \ + static struct lock_class_key __key; \ + \ + __init_swait_head((swh), &__key); \ + } while (0) + +/* + * Waiter functions + */ +extern void swait_prepare_locked(struct swait_head *head, struct swaiter *w); +extern void swait_prepare(struct swait_head *head, struct swaiter *w, int state); +extern void swait_finish_locked(struct swait_head *head, struct swaiter *w); +extern void swait_finish(struct swait_head *head, struct swaiter *w); + +/* Check whether a head has waiters enqueued */ +static inline bool swaitqueue_active(struct swait_head *h) +{ + /* Make sure the condition is visible before checking list_empty() */ + smp_mb(); + return !list_empty(&h->list); +} + +/* + * Wakeup functions + */ +extern unsigned int __swait_wake(struct swait_head *head, unsigned int state, unsigned int num); +extern unsigned int __swait_wake_locked(struct swait_head *head, unsigned int state, unsigned int num); + +#define swait_wake(head) __swait_wake(head, TASK_NORMAL, 1) +#define swait_wake_interruptible(head) __swait_wake(head, TASK_INTERRUPTIBLE, 1) +#define swait_wake_all(head) __swait_wake(head, TASK_NORMAL, 0) +#define swait_wake_all_interruptible(head) __swait_wake(head, TASK_INTERRUPTIBLE, 0) + +/* + * Event API + */ +#define __swait_event(wq, condition) \ +do { \ + DEFINE_SWAITER(__wait); \ + \ + for (;;) { \ + swait_prepare(&wq, &__wait, TASK_UNINTERRUPTIBLE); \ + if (condition) \ + break; \ + schedule(); \ + } \ + swait_finish(&wq, &__wait); \ +} while (0) + +/** + * swait_event - sleep until a condition gets true + * @wq: the waitqueue to wait on + * @condition: a C expression for the event to wait for + * + * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the + * @condition evaluates to true. The @condition is checked each time + * the waitqueue @wq is woken up. + * + * wake_up() has to be called after changing any variable that could + * change the result of the wait condition. + */ +#define swait_event(wq, condition) \ +do { \ + if (condition) \ + break; \ + __swait_event(wq, condition); \ +} while (0) + +#define __swait_event_interruptible(wq, condition, ret) \ +do { \ + DEFINE_SWAITER(__wait); \ + \ + for (;;) { \ + swait_prepare(&wq, &__wait, TASK_INTERRUPTIBLE); \ + if (condition) \ + break; \ + if (signal_pending(current)) { \ + ret = -ERESTARTSYS; \ + break; \ + } \ + schedule(); \ + } \ + swait_finish(&wq, &__wait); \ +} while (0) + +#define __swait_event_interruptible_timeout(wq, condition, ret) \ +do { \ + DEFINE_SWAITER(__wait); \ + \ + for (;;) { \ + swait_prepare(&wq, &__wait, TASK_INTERRUPTIBLE); \ + if (condition) \ + break; \ + if (signal_pending(current)) { \ + ret = -ERESTARTSYS; \ + break; \ + } \ + ret = schedule_timeout(ret); \ + if (!ret) \ + break; \ + } \ + swait_finish(&wq, &__wait); \ +} while (0) + +/** + * swait_event_interruptible - sleep until a condition gets true + * @wq: the waitqueue to wait on + * @condition: a C expression for the event to wait for + * + * The process is put to sleep (TASK_INTERRUPTIBLE) until the + * @condition evaluates to true. The @condition is checked each time + * the waitqueue @wq is woken up. + * + * wake_up() has to be called after changing any variable that could + * change the result of the wait condition. + */ +#define swait_event_interruptible(wq, condition) \ +({ \ + int __ret = 0; \ + if (!(condition)) \ + __swait_event_interruptible(wq, condition, __ret); \ + __ret; \ +}) + +#define swait_event_interruptible_timeout(wq, condition, timeout) \ +({ \ + int __ret = timeout; \ + if (!(condition)) \ + __swait_event_interruptible_timeout(wq, condition, __ret); \ + __ret; \ +}) + +#define __swait_event_timeout(wq, condition, ret) \ +do { \ + DEFINE_SWAITER(__wait); \ + \ + for (;;) { \ + swait_prepare(&wq, &__wait, TASK_UNINTERRUPTIBLE); \ + if (condition) \ + break; \ + ret = schedule_timeout(ret); \ + if (!ret) \ + break; \ + } \ + swait_finish(&wq, &__wait); \ +} while (0) + +/** + * swait_event_timeout - sleep until a condition gets true or a timeout elapses + * @wq: the waitqueue to wait on + * @condition: a C expression for the event to wait for + * @timeout: timeout, in jiffies + * + * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the + * @condition evaluates to true. The @condition is checked each time + * the waitqueue @wq is woken up. + * + * wake_up() has to be called after changing any variable that could + * change the result of the wait condition. + * + * The function returns 0 if the @timeout elapsed, and the remaining + * jiffies if the condition evaluated to true before the timeout elapsed. + */ +#define swait_event_timeout(wq, condition, timeout) \ +({ \ + long __ret = timeout; \ + if (!(condition)) \ + __swait_event_timeout(wq, condition, __ret); \ + __ret; \ +}) + +#endif Index: linux-3.12.19-rt30/include/linux/wait.h =================================================================== --- linux-3.12.19-rt30.orig/include/linux/wait.h +++ linux-3.12.19-rt30/include/linux/wait.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:10 @ #include <linux/spinlock.h> #include <asm/current.h> #include <uapi/linux/wait.h> +#include <linux/atomic.h> typedef struct __wait_queue wait_queue_t; typedef int (*wait_queue_func_t)(wait_queue_t *wait, unsigned mode, int flags, void *key); Index: linux-3.12.19-rt30/include/net/dst.h =================================================================== --- linux-3.12.19-rt30.orig/include/net/dst.h +++ linux-3.12.19-rt30/include/net/dst.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:398 @ static inline void dst_confirm(struct ds static inline int dst_neigh_output(struct dst_entry *dst, struct neighbour *n, struct sk_buff *skb) { - const struct hh_cache *hh; + struct hh_cache *hh; if (dst->pending_confirm) { unsigned long now = jiffies; Index: linux-3.12.19-rt30/include/net/neighbour.h =================================================================== --- linux-3.12.19-rt30.orig/include/net/neighbour.h +++ linux-3.12.19-rt30/include/net/neighbour.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:336 @ static inline int neigh_hh_bridge(struct } #endif -static inline int neigh_hh_output(const struct hh_cache *hh, struct sk_buff *skb) +static inline int neigh_hh_output(struct hh_cache *hh, struct sk_buff *skb) { unsigned int seq; int hh_len; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:391 @ struct neighbour_cb { #define NEIGH_CB(skb) ((struct neighbour_cb *)(skb)->cb) -static inline void neigh_ha_snapshot(char *dst, const struct neighbour *n, +static inline void neigh_ha_snapshot(char *dst, struct neighbour *n, const struct net_device *dev) { unsigned int seq; Index: linux-3.12.19-rt30/include/net/netns/ipv4.h =================================================================== --- linux-3.12.19-rt30.orig/include/net/netns/ipv4.h +++ linux-3.12.19-rt30/include/net/netns/ipv4.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:60 @ struct netns_ipv4 { int sysctl_icmp_echo_ignore_all; int sysctl_icmp_echo_ignore_broadcasts; + int sysctl_icmp_echo_sysrq; int sysctl_icmp_ignore_bogus_error_responses; int sysctl_icmp_ratelimit; int sysctl_icmp_ratemask; Index: linux-3.12.19-rt30/include/trace/events/hist.h =================================================================== --- /dev/null +++ linux-3.12.19-rt30/include/trace/events/hist.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:4 @ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM hist + +#if !defined(_TRACE_HIST_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_HIST_H + +#include "latency_hist.h" +#include <linux/tracepoint.h> + +#if !defined(CONFIG_PREEMPT_OFF_HIST) && !defined(CONFIG_INTERRUPT_OFF_HIST) +#define trace_preemptirqsoff_hist(a, b) +#else +TRACE_EVENT(preemptirqsoff_hist, + + TP_PROTO(int reason, int starthist), + + TP_ARGS(reason, starthist), + + TP_STRUCT__entry( + __field(int, reason) + __field(int, starthist) + ), + + TP_fast_assign( + __entry->reason = reason; + __entry->starthist = starthist; + ), + + TP_printk("reason=%s starthist=%s", getaction(__entry->reason), + __entry->starthist ? "start" : "stop") +); +#endif + +#ifndef CONFIG_MISSED_TIMER_OFFSETS_HIST +#define trace_hrtimer_interrupt(a, b, c, d) +#else +TRACE_EVENT(hrtimer_interrupt, + + TP_PROTO(int cpu, long long offset, struct task_struct *curr, + struct task_struct *task), + + TP_ARGS(cpu, offset, curr, task), + + TP_STRUCT__entry( + __field(int, cpu) + __field(long long, offset) + __array(char, ccomm, TASK_COMM_LEN) + __field(int, cprio) + __array(char, tcomm, TASK_COMM_LEN) + __field(int, tprio) + ), + + TP_fast_assign( + __entry->cpu = cpu; + __entry->offset = offset; + memcpy(__entry->ccomm, curr->comm, TASK_COMM_LEN); + __entry->cprio = curr->prio; + memcpy(__entry->tcomm, task != NULL ? task->comm : "<none>", + task != NULL ? TASK_COMM_LEN : 7); + __entry->tprio = task != NULL ? task->prio : -1; + ), + + TP_printk("cpu=%d offset=%lld curr=%s[%d] thread=%s[%d]", + __entry->cpu, __entry->offset, __entry->ccomm, + __entry->cprio, __entry->tcomm, __entry->tprio) +); +#endif + +#endif /* _TRACE_HIST_H */ + +/* This part must be outside protection */ +#include <trace/define_trace.h> Index: linux-3.12.19-rt30/include/trace/events/latency_hist.h =================================================================== --- /dev/null +++ linux-3.12.19-rt30/include/trace/events/latency_hist.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:4 @ +#ifndef _LATENCY_HIST_H +#define _LATENCY_HIST_H + +enum hist_action { + IRQS_ON, + PREEMPT_ON, + TRACE_STOP, + IRQS_OFF, + PREEMPT_OFF, + TRACE_START, +}; + +static char *actions[] = { + "IRQS_ON", + "PREEMPT_ON", + "TRACE_STOP", + "IRQS_OFF", + "PREEMPT_OFF", + "TRACE_START", +}; + +static inline char *getaction(int action) +{ + if (action >= 0 && action <= sizeof(actions)/sizeof(actions[0])) + return actions[action]; + return "unknown"; +} + +#endif /* _LATENCY_HIST_H */ Index: linux-3.12.19-rt30/init/Kconfig =================================================================== --- linux-3.12.19-rt30.orig/init/Kconfig +++ linux-3.12.19-rt30/init/Kconfig @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:618 @ config RCU_FANOUT_EXACT config RCU_FAST_NO_HZ bool "Accelerate last non-dyntick-idle CPU's grace periods" - depends on NO_HZ_COMMON && SMP + depends on NO_HZ_COMMON && SMP && !PREEMPT_RT_FULL default n help This option permits CPUs to enter dynticks-idle state even if @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:645 @ config TREE_RCU_TRACE config RCU_BOOST bool "Enable RCU priority boosting" depends on RT_MUTEXES && PREEMPT_RCU - default n + default y if PREEMPT_RT_FULL help This option boosts the priority of preempted RCU readers that block the current preemptible RCU grace period for too long. @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1045 @ config CFS_BANDWIDTH config RT_GROUP_SCHED bool "Group scheduling for SCHED_RR/FIFO" depends on CGROUP_SCHED + depends on !PREEMPT_RT_FULL default n help This feature lets you explicitly allocate real CPU bandwidth @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1587 @ choice config SLAB bool "SLAB" + depends on !PREEMPT_RT_FULL help The regular slab allocator that is established and known to work well in all environments. It organizes cache hot objects in @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1606 @ config SLUB config SLOB depends on EXPERT bool "SLOB (Simple Allocator)" + depends on !PREEMPT_RT_FULL help SLOB replaces the stock allocator with a drastically simpler allocator. SLOB is generally more space efficient but Index: linux-3.12.19-rt30/init/Makefile =================================================================== --- linux-3.12.19-rt30.orig/init/Makefile +++ linux-3.12.19-rt30/init/Makefile @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:36 @ silent_chk_compile.h = : include/generated/compile.h: FORCE @$($(quiet)chk_compile.h) $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkcompile_h $@ \ - "$(UTS_MACHINE)" "$(CONFIG_SMP)" "$(CONFIG_PREEMPT)" "$(CC) $(KBUILD_CFLAGS)" + "$(UTS_MACHINE)" "$(CONFIG_SMP)" "$(CONFIG_PREEMPT)" "$(CONFIG_PREEMPT_RT_FULL)" "$(CC) $(KBUILD_CFLAGS)" Index: linux-3.12.19-rt30/init/main.c =================================================================== --- linux-3.12.19-rt30.orig/init/main.c +++ linux-3.12.19-rt30/init/main.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:9 @ * GK 2/5/95 - Changed to support mounting root fs via NFS * Added initrd & change_root: Werner Almesberger & Hans Lermen, Feb '96 * Moan early if gcc is old, avoiding bogus kernels - Paul Gortmaker, May '96 - * Simplified starting of init: Michael A. Griffith <grif@acm.org> + * Simplified starting of init: Michael A. Griffith <grif@acm.org> */ #define DEBUG /* Enable initcall_debug */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:77 @ #include <linux/ptrace.h> #include <linux/blkdev.h> #include <linux/elevator.h> +#include <linux/posix-timers.h> #include <linux/sched_clock.h> #include <linux/context_tracking.h> #include <linux/random.h> @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:511 @ asmlinkage void __init start_kernel(void setup_command_line(command_line); setup_nr_cpu_ids(); setup_per_cpu_areas(); + softirq_early_init(); smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */ build_all_zonelists(NULL, NULL); Index: linux-3.12.19-rt30/ipc/mqueue.c =================================================================== --- linux-3.12.19-rt30.orig/ipc/mqueue.c +++ linux-3.12.19-rt30/ipc/mqueue.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:926 @ static inline void pipelined_send(struct struct msg_msg *message, struct ext_wait_queue *receiver) { + /* + * Keep them in one critical section for PREEMPT_RT: + */ + preempt_disable_rt(); receiver->msg = message; list_del(&receiver->list); receiver->state = STATE_PENDING; wake_up_process(receiver->task); smp_wmb(); receiver->state = STATE_READY; + preempt_enable_rt(); } /* pipelined_receive() - if there is task waiting in sys_mq_timedsend() @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:950 @ static inline void pipelined_receive(str wake_up_interruptible(&info->wait_q); return; } - if (msg_insert(sender->msg, info)) - return; - list_del(&sender->list); - sender->state = STATE_PENDING; - wake_up_process(sender->task); - smp_wmb(); - sender->state = STATE_READY; + /* + * Keep them in one critical section for PREEMPT_RT: + */ + preempt_disable_rt(); + if (!msg_insert(sender->msg, info)) { + list_del(&sender->list); + sender->state = STATE_PENDING; + wake_up_process(sender->task); + smp_wmb(); + sender->state = STATE_READY; + } + preempt_enable_rt(); } SYSCALL_DEFINE5(mq_timedsend, mqd_t, mqdes, const char __user *, u_msg_ptr, Index: linux-3.12.19-rt30/ipc/msg.c =================================================================== --- linux-3.12.19-rt30.orig/ipc/msg.c +++ linux-3.12.19-rt30/ipc/msg.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:256 @ static void expunge_all(struct msg_queue struct msg_receiver *msr, *t; list_for_each_entry_safe(msr, t, &msq->q_receivers, r_list) { + /* + * Make sure that the wakeup doesnt preempt + * this CPU prematurely. (on PREEMPT_RT) + */ + preempt_disable_rt(); + msr->r_msg = NULL; wake_up_process(msr->r_tsk); smp_mb(); msr->r_msg = ERR_PTR(res); + + preempt_enable_rt(); } } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:647 @ static inline int pipelined_send(struct !security_msg_queue_msgrcv(msq, msg, msr->r_tsk, msr->r_msgtype, msr->r_mode)) { + /* + * Make sure that the wakeup doesnt preempt + * this CPU prematurely. (on PREEMPT_RT) + */ + preempt_disable_rt(); + list_del(&msr->r_list); if (msr->r_maxsize < msg->m_ts) { msr->r_msg = NULL; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:666 @ static inline int pipelined_send(struct wake_up_process(msr->r_tsk); smp_mb(); msr->r_msg = msg; + preempt_enable_rt(); return 1; } + preempt_enable_rt(); } } return 0; Index: linux-3.12.19-rt30/ipc/sem.c =================================================================== --- linux-3.12.19-rt30.orig/ipc/sem.c +++ linux-3.12.19-rt30/ipc/sem.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:669 @ undo: static void wake_up_sem_queue_prepare(struct list_head *pt, struct sem_queue *q, int error) { +#ifdef CONFIG_PREEMPT_RT_BASE + struct task_struct *p = q->sleeper; + get_task_struct(p); + q->status = error; + wake_up_process(p); + put_task_struct(p); +#else if (list_empty(pt)) { /* * Hold preempt off so that we don't get preempted and have the @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:687 @ static void wake_up_sem_queue_prepare(st q->pid = error; list_add_tail(&q->list, pt); +#endif } /** @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:701 @ static void wake_up_sem_queue_prepare(st */ static void wake_up_sem_queue_do(struct list_head *pt) { +#ifndef CONFIG_PREEMPT_RT_BASE struct sem_queue *q, *t; int did_something; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:714 @ static void wake_up_sem_queue_do(struct } if (did_something) preempt_enable(); +#endif } static void unlink_queue(struct sem_array *sma, struct sem_queue *q) Index: linux-3.12.19-rt30/kernel/Kconfig.locks =================================================================== --- linux-3.12.19-rt30.orig/kernel/Kconfig.locks +++ linux-3.12.19-rt30/kernel/Kconfig.locks @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:228 @ config ARCH_SUPPORTS_ATOMIC_RMW config MUTEX_SPIN_ON_OWNER def_bool y - depends on SMP && !DEBUG_MUTEXES && ARCH_SUPPORTS_ATOMIC_RMW + depends on SMP && !DEBUG_MUTEXES && ARCH_SUPPORTS_ATOMIC_RMW && !PREEMPT_RT_FULL Index: linux-3.12.19-rt30/kernel/Kconfig.preempt =================================================================== --- linux-3.12.19-rt30.orig/kernel/Kconfig.preempt +++ linux-3.12.19-rt30/kernel/Kconfig.preempt @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:4 @ +config PREEMPT + bool + select PREEMPT_COUNT + +config PREEMPT_RT_BASE + bool + select PREEMPT + +config HAVE_PREEMPT_LAZY + bool + +config PREEMPT_LAZY + def_bool y if HAVE_PREEMPT_LAZY && PREEMPT_RT_FULL choice prompt "Preemption Model" @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:49 @ config PREEMPT_VOLUNTARY Select this if you are building a kernel for a desktop system. -config PREEMPT +config PREEMPT__LL bool "Preemptible Kernel (Low-Latency Desktop)" - select PREEMPT_COUNT + select PREEMPT select UNINLINE_SPIN_UNLOCK if !ARCH_INLINE_SPIN_UNLOCK help This option reduces the latency of the kernel by making @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:68 @ config PREEMPT embedded system with latency requirements in the milliseconds range. +config PREEMPT_RTB + bool "Preemptible Kernel (Basic RT)" + select PREEMPT_RT_BASE + help + This option is basically the same as (Low-Latency Desktop) but + enables changes which are preliminary for the full preemptible + RT kernel. + +config PREEMPT_RT_FULL + bool "Fully Preemptible Kernel (RT)" + depends on IRQ_FORCED_THREADING + select PREEMPT_RT_BASE + select PREEMPT_RCU + help + All and everything + endchoice config PREEMPT_COUNT Index: linux-3.12.19-rt30/kernel/Makefile =================================================================== --- linux-3.12.19-rt30.orig/kernel/Makefile +++ linux-3.12.19-rt30/kernel/Makefile @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:10 @ obj-y = fork.o exec_domain.o panic.o sysctl.o sysctl_binary.o capability.o ptrace.o timer.o user.o \ signal.o sys.o kmod.o workqueue.o pid.o task_work.o \ rcupdate.o extable.o params.o posix-timers.o \ - kthread.o wait.o sys_ni.o posix-cpu-timers.o mutex.o \ - hrtimer.o rwsem.o nsproxy.o srcu.o semaphore.o \ + kthread.o wait.o sys_ni.o posix-cpu-timers.o \ + hrtimer.o nsproxy.o srcu.o semaphore.o \ notifier.o ksysfs.o cred.o reboot.o \ - async.o range.o groups.o lglock.o smpboot.o + async.o range.o groups.o lglock.o smpboot.o wait-simple.o ifdef CONFIG_FUNCTION_TRACER # Do not trace debug files and internal ftrace files @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:36 @ obj-$(CONFIG_FREEZER) += freezer.o obj-$(CONFIG_PROFILING) += profile.o obj-$(CONFIG_STACKTRACE) += stacktrace.o obj-y += time/ +ifneq ($(CONFIG_PREEMPT_RT_FULL),y) +obj-y += mutex.o obj-$(CONFIG_DEBUG_MUTEXES) += mutex-debug.o +obj-y += rwsem.o +endif obj-$(CONFIG_LOCKDEP) += lockdep.o ifeq ($(CONFIG_PROC_FS),y) obj-$(CONFIG_LOCKDEP) += lockdep_proc.o @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:52 @ endif obj-$(CONFIG_RT_MUTEXES) += rtmutex.o obj-$(CONFIG_DEBUG_RT_MUTEXES) += rtmutex-debug.o obj-$(CONFIG_RT_MUTEX_TESTER) += rtmutex-tester.o +obj-$(CONFIG_PREEMPT_RT_FULL) += rt.o obj-$(CONFIG_GENERIC_ISA_DMA) += dma.o obj-$(CONFIG_SMP) += smp.o ifneq ($(CONFIG_SMP),y) Index: linux-3.12.19-rt30/kernel/cpu.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/cpu.c +++ linux-3.12.19-rt30/kernel/cpu.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:66 @ static struct { .refcount = 0, }; +/** + * hotplug_pcp - per cpu hotplug descriptor + * @unplug: set when pin_current_cpu() needs to sync tasks + * @sync_tsk: the task that waits for tasks to finish pinned sections + * @refcount: counter of tasks in pinned sections + * @grab_lock: set when the tasks entering pinned sections should wait + * @synced: notifier for @sync_tsk to tell cpu_down it's finished + * @mutex: the mutex to make tasks wait (used when @grab_lock is true) + * @mutex_init: zero if the mutex hasn't been initialized yet. + * + * Although @unplug and @sync_tsk may point to the same task, the @unplug + * is used as a flag and still exists after @sync_tsk has exited and + * @sync_tsk set to NULL. + */ +struct hotplug_pcp { + struct task_struct *unplug; + struct task_struct *sync_tsk; + int refcount; + int grab_lock; + struct completion synced; + struct completion unplug_wait; +#ifdef CONFIG_PREEMPT_RT_FULL + /* + * Note, on PREEMPT_RT, the hotplug lock must save the state of + * the task, otherwise the mutex will cause the task to fail + * to sleep when required. (Because it's called from migrate_disable()) + * + * The spinlock_t on PREEMPT_RT is a mutex that saves the task's + * state. + */ + spinlock_t lock; +#else + struct mutex mutex; +#endif + int mutex_init; +}; + +#ifdef CONFIG_PREEMPT_RT_FULL +# define hotplug_lock(hp) rt_spin_lock(&(hp)->lock) +# define hotplug_unlock(hp) rt_spin_unlock(&(hp)->lock) +#else +# define hotplug_lock(hp) mutex_lock(&(hp)->mutex) +# define hotplug_unlock(hp) mutex_unlock(&(hp)->mutex) +#endif + +static DEFINE_PER_CPU(struct hotplug_pcp, hotplug_pcp); + +/** + * pin_current_cpu - Prevent the current cpu from being unplugged + * + * Lightweight version of get_online_cpus() to prevent cpu from being + * unplugged when code runs in a migration disabled region. + * + * Must be called with preemption disabled (preempt_count = 1)! + */ +void pin_current_cpu(void) +{ + struct hotplug_pcp *hp; + int force = 0; + +retry: + hp = &__get_cpu_var(hotplug_pcp); + + if (!hp->unplug || hp->refcount || force || preempt_count() > 1 || + hp->unplug == current) { + hp->refcount++; + return; + } + if (hp->grab_lock) { + preempt_enable(); + hotplug_lock(hp); + hotplug_unlock(hp); + } else { + preempt_enable(); + /* + * Try to push this task off of this CPU. + */ + if (!migrate_me()) { + preempt_disable(); + hp = &__get_cpu_var(hotplug_pcp); + if (!hp->grab_lock) { + /* + * Just let it continue it's already pinned + * or about to sleep. + */ + force = 1; + goto retry; + } + preempt_enable(); + } + } + preempt_disable(); + goto retry; +} + +/** + * unpin_current_cpu - Allow unplug of current cpu + * + * Must be called with preemption or interrupts disabled! + */ +void unpin_current_cpu(void) +{ + struct hotplug_pcp *hp = &__get_cpu_var(hotplug_pcp); + + WARN_ON(hp->refcount <= 0); + + /* This is safe. sync_unplug_thread is pinned to this cpu */ + if (!--hp->refcount && hp->unplug && hp->unplug != current) + wake_up_process(hp->unplug); +} + +static void wait_for_pinned_cpus(struct hotplug_pcp *hp) +{ + set_current_state(TASK_UNINTERRUPTIBLE); + while (hp->refcount) { + schedule_preempt_disabled(); + set_current_state(TASK_UNINTERRUPTIBLE); + } +} + +static int sync_unplug_thread(void *data) +{ + struct hotplug_pcp *hp = data; + + wait_for_completion(&hp->unplug_wait); + preempt_disable(); + hp->unplug = current; + wait_for_pinned_cpus(hp); + + /* + * This thread will synchronize the cpu_down() with threads + * that have pinned the CPU. When the pinned CPU count reaches + * zero, we inform the cpu_down code to continue to the next step. + */ + set_current_state(TASK_UNINTERRUPTIBLE); + preempt_enable(); + complete(&hp->synced); + + /* + * If all succeeds, the next step will need tasks to wait till + * the CPU is offline before continuing. To do this, the grab_lock + * is set and tasks going into pin_current_cpu() will block on the + * mutex. But we still need to wait for those that are already in + * pinned CPU sections. If the cpu_down() failed, the kthread_should_stop() + * will kick this thread out. + */ + while (!hp->grab_lock && !kthread_should_stop()) { + schedule(); + set_current_state(TASK_UNINTERRUPTIBLE); + } + + /* Make sure grab_lock is seen before we see a stale completion */ + smp_mb(); + + /* + * Now just before cpu_down() enters stop machine, we need to make + * sure all tasks that are in pinned CPU sections are out, and new + * tasks will now grab the lock, keeping them from entering pinned + * CPU sections. + */ + if (!kthread_should_stop()) { + preempt_disable(); + wait_for_pinned_cpus(hp); + preempt_enable(); + complete(&hp->synced); + } + + set_current_state(TASK_UNINTERRUPTIBLE); + while (!kthread_should_stop()) { + schedule(); + set_current_state(TASK_UNINTERRUPTIBLE); + } + set_current_state(TASK_RUNNING); + + /* + * Force this thread off this CPU as it's going down and + * we don't want any more work on this CPU. + */ + current->flags &= ~PF_NO_SETAFFINITY; + do_set_cpus_allowed(current, cpu_present_mask); + migrate_me(); + return 0; +} + +static void __cpu_unplug_sync(struct hotplug_pcp *hp) +{ + wake_up_process(hp->sync_tsk); + wait_for_completion(&hp->synced); +} + +static void __cpu_unplug_wait(unsigned int cpu) +{ + struct hotplug_pcp *hp = &per_cpu(hotplug_pcp, cpu); + + complete(&hp->unplug_wait); + wait_for_completion(&hp->synced); +} + +/* + * Start the sync_unplug_thread on the target cpu and wait for it to + * complete. + */ +static int cpu_unplug_begin(unsigned int cpu) +{ + struct hotplug_pcp *hp = &per_cpu(hotplug_pcp, cpu); + int err; + + /* Protected by cpu_hotplug.lock */ + if (!hp->mutex_init) { +#ifdef CONFIG_PREEMPT_RT_FULL + spin_lock_init(&hp->lock); +#else + mutex_init(&hp->mutex); +#endif + hp->mutex_init = 1; + } + + /* Inform the scheduler to migrate tasks off this CPU */ + tell_sched_cpu_down_begin(cpu); + + init_completion(&hp->synced); + init_completion(&hp->unplug_wait); + + hp->sync_tsk = kthread_create(sync_unplug_thread, hp, "sync_unplug/%d", cpu); + if (IS_ERR(hp->sync_tsk)) { + err = PTR_ERR(hp->sync_tsk); + hp->sync_tsk = NULL; + return err; + } + kthread_bind(hp->sync_tsk, cpu); + + /* + * Wait for tasks to get out of the pinned sections, + * it's still OK if new tasks enter. Some CPU notifiers will + * wait for tasks that are going to enter these sections and + * we must not have them block. + */ + wake_up_process(hp->sync_tsk); + return 0; +} + +static void cpu_unplug_sync(unsigned int cpu) +{ + struct hotplug_pcp *hp = &per_cpu(hotplug_pcp, cpu); + + init_completion(&hp->synced); + /* The completion needs to be initialzied before setting grab_lock */ + smp_wmb(); + + /* Grab the mutex before setting grab_lock */ + hotplug_lock(hp); + hp->grab_lock = 1; + + /* + * The CPU notifiers have been completed. + * Wait for tasks to get out of pinned CPU sections and have new + * tasks block until the CPU is completely down. + */ + __cpu_unplug_sync(hp); + + /* All done with the sync thread */ + kthread_stop(hp->sync_tsk); + hp->sync_tsk = NULL; +} + +static void cpu_unplug_done(unsigned int cpu) +{ + struct hotplug_pcp *hp = &per_cpu(hotplug_pcp, cpu); + + hp->unplug = NULL; + /* Let all tasks know cpu unplug is finished before cleaning up */ + smp_wmb(); + + if (hp->sync_tsk) + kthread_stop(hp->sync_tsk); + + if (hp->grab_lock) { + hotplug_unlock(hp); + /* protected by cpu_hotplug.lock */ + hp->grab_lock = 0; + } + tell_sched_cpu_down_done(cpu); +} + void get_online_cpus(void) { might_sleep(); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:366 @ void put_online_cpus(void) { if (cpu_hotplug.active_writer == current) return; - mutex_lock(&cpu_hotplug.lock); + mutex_lock(&cpu_hotplug.lock); if (WARN_ON(!cpu_hotplug.refcount)) cpu_hotplug.refcount++; /* try to fix things up */ if (!--cpu_hotplug.refcount && unlikely(cpu_hotplug.active_writer)) wake_up_process(cpu_hotplug.active_writer); mutex_unlock(&cpu_hotplug.lock); - } EXPORT_SYMBOL_GPL(put_online_cpus); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:568 @ static int __ref take_cpu_down(void *_pa /* Requires cpu_add_remove_lock to be held */ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) { - int err, nr_calls = 0; + int mycpu, err, nr_calls = 0; void *hcpu = (void *)(long)cpu; unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0; struct take_cpu_down_param tcd_param = { .mod = mod, .hcpu = hcpu, }; + cpumask_var_t cpumask; + cpumask_var_t cpumask_org; if (num_online_cpus() == 1) return -EBUSY; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:584 @ static int __ref _cpu_down(unsigned int if (!cpu_online(cpu)) return -EINVAL; + /* Move the downtaker off the unplug cpu */ + if (!alloc_cpumask_var(&cpumask, GFP_KERNEL)) + return -ENOMEM; + if (!alloc_cpumask_var(&cpumask_org, GFP_KERNEL)) { + free_cpumask_var(cpumask); + return -ENOMEM; + } + + cpumask_copy(cpumask_org, tsk_cpus_allowed(current)); + cpumask_andnot(cpumask, cpu_online_mask, cpumask_of(cpu)); + set_cpus_allowed_ptr(current, cpumask); + free_cpumask_var(cpumask); + migrate_disable(); + mycpu = smp_processor_id(); + if (mycpu == cpu) { + printk(KERN_ERR "Yuck! Still on unplug CPU\n!"); + migrate_enable(); + err = -EBUSY; + goto restore_cpus; + } + migrate_enable(); + cpu_hotplug_begin(); + err = cpu_unplug_begin(cpu); + if (err) { + printk("cpu_unplug_begin(%d) failed\n", cpu); + goto out_cancel; + } err = __cpu_notify(CPU_DOWN_PREPARE | mod, hcpu, -1, &nr_calls); if (err) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:621 @ static int __ref _cpu_down(unsigned int __func__, cpu); goto out_release; } + + __cpu_unplug_wait(cpu); smpboot_park_threads(cpu); + /* Notifiers are done. Don't let any more tasks pin this CPU. */ + cpu_unplug_sync(cpu); + err = __stop_machine(take_cpu_down, &tcd_param, cpumask_of(cpu)); if (err) { /* CPU didn't die: tell everyone. Can't complain. */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:656 @ static int __ref _cpu_down(unsigned int check_for_tasks(cpu); out_release: + cpu_unplug_done(cpu); +out_cancel: cpu_hotplug_done(); if (!err) cpu_notify_nofail(CPU_POST_DEAD | mod, hcpu); +restore_cpus: + set_cpus_allowed_ptr(current, cpumask_org); + free_cpumask_var(cpumask_org); return err; } Index: linux-3.12.19-rt30/kernel/debug/kdb/kdb_io.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/debug/kdb/kdb_io.c +++ linux-3.12.19-rt30/kernel/debug/kdb/kdb_io.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:557 @ int vkdb_printf(const char *fmt, va_list int linecount; int colcount; int logging, saved_loglevel = 0; - int saved_trap_printk; int got_printf_lock = 0; int retlen = 0; int fnd, len; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:567 @ int vkdb_printf(const char *fmt, va_list unsigned long uninitialized_var(flags); preempt_disable(); - saved_trap_printk = kdb_trap_printk; - kdb_trap_printk = 0; /* Serialize kdb_printf if multiple cpus try to write at once. * But if any cpu goes recursive in kdb, just print the output, @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:833 @ kdb_print_out: } else { __release(kdb_printf_lock); } - kdb_trap_printk = saved_trap_printk; preempt_enable(); return retlen; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:842 @ int kdb_printf(const char *fmt, ...) va_list ap; int r; + kdb_trap_printk++; va_start(ap, fmt); r = vkdb_printf(fmt, ap); va_end(ap); + kdb_trap_printk--; return r; } Index: linux-3.12.19-rt30/kernel/events/core.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/events/core.c +++ linux-3.12.19-rt30/kernel/events/core.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:6059 @ static void perf_swevent_init_hrtimer(st hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); hwc->hrtimer.function = perf_swevent_hrtimer; + hwc->hrtimer.irqsafe = 1; /* * Since hrtimers have a fixed rate, we can do a static freq->period Index: linux-3.12.19-rt30/kernel/exit.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/exit.c +++ linux-3.12.19-rt30/kernel/exit.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:149 @ static void __exit_signal(struct task_st * 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); Index: linux-3.12.19-rt30/kernel/fork.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/fork.c +++ linux-3.12.19-rt30/kernel/fork.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:99 @ int max_threads; /* tunable limit on nr DEFINE_PER_CPU(unsigned long, process_counts) = 0; -__cacheline_aligned DEFINE_RWLOCK(tasklist_lock); /* outer */ +DEFINE_RWLOCK(tasklist_lock); /* outer */ #ifdef CONFIG_PROVE_RCU int lockdep_tasklist_lock_is_held(void) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:235 @ static inline void put_signal_struct(str if (atomic_dec_and_test(&sig->sigcnt)) free_signal_struct(sig); } - +#ifdef CONFIG_PREEMPT_RT_BASE +static +#endif void __put_task_struct(struct task_struct *tsk) { WARN_ON(!tsk->exit_state); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:252 @ void __put_task_struct(struct task_struc if (!profile_handoff_task(tsk)) free_task(tsk); } +#ifndef CONFIG_PREEMPT_RT_BASE EXPORT_SYMBOL_GPL(__put_task_struct); +#else +void __put_task_struct_cb(struct rcu_head *rhp) +{ + struct task_struct *tsk = container_of(rhp, struct task_struct, put_rcu); + + __put_task_struct(tsk); + +} +EXPORT_SYMBOL_GPL(__put_task_struct_cb); +#endif void __init __weak arch_task_cache_init(void) { } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:616 @ void __mmdrop(struct mm_struct *mm) } EXPORT_SYMBOL_GPL(__mmdrop); +#ifdef CONFIG_PREEMPT_RT_BASE +/* + * 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 + /* * Decrement the use count and release all resources for an mm. */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1146 @ void mm_init_owner(struct mm_struct *mm, */ static void posix_cpu_timers_init(struct task_struct *tsk) { +#ifdef CONFIG_PREEMPT_RT_BASE + tsk->posix_timer_list = NULL; +#endif tsk->cputime_expires.prof_exp = 0; tsk->cputime_expires.virt_exp = 0; tsk->cputime_expires.sched_exp = 0; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1277 @ static 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; p->utimescaled = p->stimescaled = 0; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1285 @ static struct task_struct *copy_process( p->prev_cputime.utime = p->prev_cputime.stime = 0; #endif #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN - seqlock_init(&p->vtime_seqlock); + raw_spin_lock_init(&p->vtime_lock); + seqcount_init(&p->vtime_seq); p->vtime_snap = 0; p->vtime_snap_whence = VTIME_SLEEPING; #endif @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1339 @ static struct task_struct *copy_process( p->hardirq_context = 0; p->softirq_context = 0; #endif +#ifdef CONFIG_PREEMPT_RT_FULL + p->pagefault_disabled = 0; +#endif #ifdef CONFIG_LOCKDEP p->lockdep_depth = 0; /* no locks held yet */ p->curr_chain_key = 0; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1712 @ SYSCALL_DEFINE0(fork) #ifdef __ARCH_WANT_SYS_VFORK SYSCALL_DEFINE0(vfork) { - return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, 0, + return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, 0, 0, NULL, NULL); } #endif Index: linux-3.12.19-rt30/kernel/futex.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/futex.c +++ linux-3.12.19-rt30/kernel/futex.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:578 @ void exit_pi_state_list(struct task_stru * task still owns the PI-state: */ if (head->next != next) { + raw_spin_unlock_irq(&curr->pi_lock); spin_unlock(&hb->lock); + raw_spin_lock_irq(&curr->pi_lock); continue; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1579 @ retry_private: requeue_pi_wake_futex(this, &key2, hb2); drop_count++; 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; + free_pi_state(pi_state); + continue; } else if (ret) { /* -EDEADLK */ this->pi_state = NULL; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2431 @ static int futex_wait_requeue_pi(u32 __u struct hrtimer_sleeper timeout, *to = NULL; struct rt_mutex_waiter rt_waiter; struct rt_mutex *pi_mutex = NULL; - 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; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2456 @ static int futex_wait_requeue_pi(u32 __u * The waiter is allocated on our stack, manipulated by the requeue * code while we sleep on uaddr. */ - debug_rt_mutex_init_waiter(&rt_waiter); - rt_waiter.task = NULL; + rt_mutex_init_waiter(&rt_waiter, false); ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2, VERIFY_WRITE); if (unlikely(ret != 0)) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2487 @ static int futex_wait_requeue_pi(u32 __u /* 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_put_keys; + /* + * 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(¤t->pi_lock); + if (current->pi_blocked_on) { + /* + * We have been requeued or are in the process of + * being requeued. + */ + raw_spin_unlock_irq(¤t->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(¤t->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(¤t->pi_lock); + current->pi_blocked_on = NULL; + raw_spin_unlock_irq(¤t->pi_lock); + + ret = handle_early_requeue_pi_wakeup(hb, &q, &key2, to); + spin_unlock(&hb->lock); + if (ret) + goto out_put_keys; + } /* - * 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) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2544 @ static int futex_wait_requeue_pi(u32 __u * 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); - spin_unlock(q.lock_ptr); + spin_unlock(&hb2->lock); } } else { /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2560 @ static int futex_wait_requeue_pi(u32 __u ret = rt_mutex_finish_proxy_lock(pi_mutex, to, &rt_waiter, 1); debug_rt_mutex_free_waiter(&rt_waiter); - spin_lock(q.lock_ptr); + spin_lock(&hb2->lock); + BUG_ON(&hb2->lock != q.lock_ptr); /* * Fixup the pi_state owner and possibly acquire the lock if we * haven't already. Index: linux-3.12.19-rt30/kernel/hrtimer.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/hrtimer.c +++ linux-3.12.19-rt30/kernel/hrtimer.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:50 @ #include <linux/sched/sysctl.h> #include <linux/sched/rt.h> #include <linux/timer.h> +#include <linux/kthread.h> #include <linux/freezer.h> #include <asm/uaccess.h> #include <trace/events/timer.h> +#include <trace/events/hist.h> /* * The timer bases: @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:634 @ static int hrtimer_reprogram(struct hrti * When the callback is running, we do not reprogram the clock event * device. The timer callback is either running on a different CPU or * the callback is executed in the hrtimer_interrupt context. The - * reprogramming is handled either by the softirq, which called the - * callback or at the end of the hrtimer_interrupt. + * reprogramming is handled at the end of the hrtimer_interrupt. */ if (hrtimer_callback_running(timer)) return 0; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:669 @ static int hrtimer_reprogram(struct hrti return res; } +static void __run_hrtimer(struct hrtimer *timer, ktime_t *now); +static int hrtimer_rt_defer(struct hrtimer *timer); + /* * Initialize the high resolution related parts of cpu_base */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:688 @ static inline void hrtimer_init_hres(str * and expiry check is done in the hrtimer_interrupt or in the softirq. */ static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer, - struct hrtimer_clock_base *base) + struct hrtimer_clock_base *base, + int wakeup) { - return base->cpu_base->hres_active && hrtimer_reprogram(timer, base); + if (!(base->cpu_base->hres_active && hrtimer_reprogram(timer, base))) + return 0; + if (!wakeup) + return -ETIME; +#ifdef CONFIG_PREEMPT_RT_BASE + if (!hrtimer_rt_defer(timer)) + return -ETIME; +#endif + return 1; } static inline ktime_t hrtimer_update_base(struct hrtimer_cpu_base *base) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:767 @ static void clock_was_set_work(struct wo static DECLARE_WORK(hrtimer_work, clock_was_set_work); +#ifdef CONFIG_PREEMPT_RT_FULL +/* + * RT can not call schedule_work from real interrupt context. + * Need to make a thread to do the real work. + */ +static struct task_struct *clock_set_delay_thread; +static bool do_clock_set_delay; + +static int run_clock_set_delay(void *ignore) +{ + while (!kthread_should_stop()) { + set_current_state(TASK_INTERRUPTIBLE); + if (do_clock_set_delay) { + do_clock_set_delay = false; + schedule_work(&hrtimer_work); + } + schedule(); + } + __set_current_state(TASK_RUNNING); + return 0; +} + +void clock_was_set_delayed(void) +{ + do_clock_set_delay = true; + /* Make visible before waking up process */ + smp_wmb(); + wake_up_process(clock_set_delay_thread); +} + +static __init int create_clock_set_delay_thread(void) +{ + clock_set_delay_thread = kthread_run(run_clock_set_delay, NULL, "kclksetdelayd"); + BUG_ON(!clock_set_delay_thread); + return 0; +} +early_initcall(create_clock_set_delay_thread); +#else /* PREEMPT_RT_FULL */ /* * Called from timekeeping and resume code to reprogramm the hrtimer * interrupt device on all cpus. @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:813 @ void clock_was_set_delayed(void) { schedule_work(&hrtimer_work); } +#endif #else @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:823 @ static inline int hrtimer_switch_to_hres static inline void hrtimer_force_reprogram(struct hrtimer_cpu_base *base, int skip_equal) { } static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer, - struct hrtimer_clock_base *base) + struct hrtimer_clock_base *base, + int wakeup) { return 0; } static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base) { } static inline void retrigger_next_event(void *arg) { } +static inline int hrtimer_reprogram(struct hrtimer *timer, + struct hrtimer_clock_base *base) +{ + return 0; +} #endif /* CONFIG_HIGH_RES_TIMERS */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:953 @ u64 hrtimer_forward(struct hrtimer *time } EXPORT_SYMBOL_GPL(hrtimer_forward); +#ifdef CONFIG_PREEMPT_RT_BASE +# define wake_up_timer_waiters(b) wake_up(&(b)->wait) + +/** + * hrtimer_wait_for_timer - Wait for a running timer + * + * @timer: timer to wait for + * + * The function waits in case the timers callback function is + * currently executed on the waitqueue of the timer base. The + * waitqueue is woken up after the timer callback function has + * finished execution. + */ +void hrtimer_wait_for_timer(const struct hrtimer *timer) +{ + struct hrtimer_clock_base *base = timer->base; + + if (base && base->cpu_base && !timer->irqsafe) + wait_event(base->cpu_base->wait, + !(timer->state & HRTIMER_STATE_CALLBACK)); +} + +#else +# define wake_up_timer_waiters(b) do { } while (0) +#endif + /* * enqueue_hrtimer - internal function to (re)start a timer * @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1022 @ static void __remove_hrtimer(struct hrti if (!(timer->state & HRTIMER_STATE_ENQUEUED)) goto out; + if (unlikely(!list_empty(&timer->cb_entry))) { + list_del_init(&timer->cb_entry); + goto out; + } + next_timer = timerqueue_getnext(&base->active); timerqueue_del(&base->active, &timer->node); if (&timer->node == next_timer) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1113 @ int __hrtimer_start_range_ns(struct hrti /* Switch the timer base, if necessary: */ new_base = switch_hrtimer_base(timer, base, mode & HRTIMER_MODE_PINNED); +#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST + { + ktime_t now = new_base->get_time(); + + if (ktime_to_ns(tim) < ktime_to_ns(now)) + timer->praecox = now; + else + timer->praecox = ktime_set(0, 0); + } +#endif + timer_stats_hrtimer_set_start_info(timer); leftmost = enqueue_hrtimer(timer, new_base); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1134 @ int __hrtimer_start_range_ns(struct hrti * * XXX send_remote_softirq() ? */ - if (leftmost && new_base->cpu_base == &__get_cpu_var(hrtimer_bases) - && hrtimer_enqueue_reprogram(timer, new_base)) { - if (wakeup) { + if (leftmost && new_base->cpu_base == &__get_cpu_var(hrtimer_bases)) { + ret = hrtimer_enqueue_reprogram(timer, new_base, wakeup); + if (ret < 0) { + /* + * In case we failed to reprogram the timer (mostly + * because out current timer is already elapsed), + * remove it again and report a failure. This avoids + * stale base->first entries. + */ + debug_deactivate(timer); + __remove_hrtimer(timer, new_base, + timer->state & HRTIMER_STATE_CALLBACK, 0); + } else if (ret > 0) { /* * We need to drop cpu_base->lock to avoid a * lock ordering issue vs. rq->lock. @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1154 @ int __hrtimer_start_range_ns(struct hrti raw_spin_unlock(&new_base->cpu_base->lock); raise_softirq_irqoff(HRTIMER_SOFTIRQ); local_irq_restore(flags); - return ret; - } else { - __raise_softirq_irqoff(HRTIMER_SOFTIRQ); + return 0; } } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1244 @ int hrtimer_cancel(struct hrtimer *timer if (ret >= 0) return ret; - cpu_relax(); + hrtimer_wait_for_timer(timer); } } EXPORT_SYMBOL_GPL(hrtimer_cancel); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1323 @ static void __hrtimer_init(struct hrtime base = hrtimer_clockid_to_base(clock_id); timer->base = &cpu_base->clock_base[base]; + INIT_LIST_HEAD(&timer->cb_entry); timerqueue_init(&timer->node); #ifdef CONFIG_TIMER_STATS @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1407 @ static void __run_hrtimer(struct hrtimer timer->state &= ~HRTIMER_STATE_CALLBACK; } +static enum hrtimer_restart hrtimer_wakeup(struct hrtimer *timer); + +#ifdef CONFIG_PREEMPT_RT_BASE +static void hrtimer_rt_reprogram(int restart, struct hrtimer *timer, + struct hrtimer_clock_base *base) +{ + /* + * Note, we clear the callback flag before we requeue the + * timer otherwise we trigger the callback_running() check + * in hrtimer_reprogram(). + */ + timer->state &= ~HRTIMER_STATE_CALLBACK; + + if (restart != HRTIMER_NORESTART) { + BUG_ON(hrtimer_active(timer)); + /* + * Enqueue the timer, if it's the leftmost timer then + * we need to reprogram it. + */ + if (!enqueue_hrtimer(timer, base)) + return; + +#ifndef CONFIG_HIGH_RES_TIMERS + } +#else + if (base->cpu_base->hres_active && + hrtimer_reprogram(timer, base)) + goto requeue; + + } else if (hrtimer_active(timer)) { + /* + * If the timer was rearmed on another CPU, reprogram + * the event device. + */ + if (&timer->node == base->active.next && + base->cpu_base->hres_active && + hrtimer_reprogram(timer, base)) + goto requeue; + } + return; + +requeue: + /* + * Timer is expired. Thus move it from tree to pending list + * again. + */ + __remove_hrtimer(timer, base, timer->state, 0); + list_add_tail(&timer->cb_entry, &base->expired); +#endif +} + +/* + * The changes in mainline which removed the callback modes from + * hrtimer are not yet working with -rt. The non wakeup_process() + * based callbacks which involve sleeping locks need to be treated + * seperately. + */ +static void hrtimer_rt_run_pending(void) +{ + enum hrtimer_restart (*fn)(struct hrtimer *); + struct hrtimer_cpu_base *cpu_base; + struct hrtimer_clock_base *base; + struct hrtimer *timer; + int index, restart; + + local_irq_disable(); + cpu_base = &per_cpu(hrtimer_bases, smp_processor_id()); + + raw_spin_lock(&cpu_base->lock); + + for (index = 0; index < HRTIMER_MAX_CLOCK_BASES; index++) { + base = &cpu_base->clock_base[index]; + + while (!list_empty(&base->expired)) { + timer = list_first_entry(&base->expired, + struct hrtimer, cb_entry); + + /* + * Same as the above __run_hrtimer function + * just we run with interrupts enabled. + */ + debug_hrtimer_deactivate(timer); + __remove_hrtimer(timer, base, HRTIMER_STATE_CALLBACK, 0); + timer_stats_account_hrtimer(timer); + fn = timer->function; + + raw_spin_unlock_irq(&cpu_base->lock); + restart = fn(timer); + raw_spin_lock_irq(&cpu_base->lock); + + hrtimer_rt_reprogram(restart, timer, base); + } + } + + raw_spin_unlock_irq(&cpu_base->lock); + + wake_up_timer_waiters(cpu_base); +} + +static int hrtimer_rt_defer(struct hrtimer *timer) +{ + if (timer->irqsafe) + return 0; + + __remove_hrtimer(timer, timer->base, timer->state, 0); + list_add_tail(&timer->cb_entry, &timer->base->expired); + return 1; +} + +#else + +static inline void hrtimer_rt_run_pending(void) +{ + hrtimer_peek_ahead_timers(); +} + +static inline int hrtimer_rt_defer(struct hrtimer *timer) { return 0; } + +#endif + #ifdef CONFIG_HIGH_RES_TIMERS /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1537 @ void hrtimer_interrupt(struct clock_even { struct hrtimer_cpu_base *cpu_base = &__get_cpu_var(hrtimer_bases); ktime_t expires_next, now, entry_time, delta; - int i, retries = 0; + int i, retries = 0, raise = 0; BUG_ON(!cpu_base->hres_active); cpu_base->nr_events++; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1572 @ retry: timer = container_of(node, struct hrtimer, node); + trace_hrtimer_interrupt(raw_smp_processor_id(), + ktime_to_ns(ktime_sub(ktime_to_ns(timer->praecox) ? + timer->praecox : hrtimer_get_expires(timer), + basenow)), + current, + timer->function == hrtimer_wakeup ? + container_of(timer, struct hrtimer_sleeper, + timer)->task : NULL); + /* * The immediate goal for using the softexpires is * minimizing wakeups, not running timers at the @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1606 @ retry: break; } - __run_hrtimer(timer, &basenow); + if (!hrtimer_rt_defer(timer)) + __run_hrtimer(timer, &basenow); + else + raise = 1; } } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1624 @ retry: if (expires_next.tv64 == KTIME_MAX || !tick_program_event(expires_next, 0)) { cpu_base->hang_detected = 0; - return; + goto out; } /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1668 @ retry: tick_program_event(expires_next, 1); printk_once(KERN_WARNING "hrtimer: interrupt took %llu ns\n", ktime_to_ns(delta)); +out: + if (raise) + raise_softirq_irqoff(HRTIMER_SOFTIRQ); } /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1706 @ void hrtimer_peek_ahead_timers(void) __hrtimer_peek_ahead_timers(); local_irq_restore(flags); } - -static void run_hrtimer_softirq(struct softirq_action *h) -{ - hrtimer_peek_ahead_timers(); -} - #else /* CONFIG_HIGH_RES_TIMERS */ static inline void __hrtimer_peek_ahead_timers(void) { } #endif /* !CONFIG_HIGH_RES_TIMERS */ -/* - * Called from timer softirq every jiffy, expire hrtimers: - * - * For HRT its the fall back code to run the softirq in the timer - * softirq context in case the hrtimer initialization failed or has - * not been done yet. - */ -void hrtimer_run_pending(void) -{ - if (hrtimer_hres_active()) - return; - /* - * This _is_ ugly: We have to check in the softirq context, - * whether we can switch to highres and / or nohz mode. The - * clocksource switch happens in the timer interrupt with - * xtime_lock held. Notification from there only sets the - * check bit in the tick_oneshot code, otherwise we might - * deadlock vs. xtime_lock. - */ - if (tick_check_oneshot_change(!hrtimer_is_hres_enabled())) - hrtimer_switch_to_hres(); +static void run_hrtimer_softirq(struct softirq_action *h) +{ + hrtimer_rt_run_pending(); } /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1726 @ void hrtimer_run_queues(void) struct timerqueue_node *node; struct hrtimer_cpu_base *cpu_base = &__get_cpu_var(hrtimer_bases); struct hrtimer_clock_base *base; - int index, gettime = 1; + int index, gettime = 1, raise = 0; if (hrtimer_hres_active()) return; + /* + * Check whether we can switch to highres mode. + */ + if (tick_check_oneshot_change(!hrtimer_is_hres_enabled()) + && hrtimer_switch_to_hres()) + return; + for (index = 0; index < HRTIMER_MAX_CLOCK_BASES; index++) { base = &cpu_base->clock_base[index]; if (!timerqueue_getnext(&base->active)) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1758 @ void hrtimer_run_queues(void) hrtimer_get_expires_tv64(timer)) break; - __run_hrtimer(timer, &base->softirq_time); + if (!hrtimer_rt_defer(timer)) + __run_hrtimer(timer, &base->softirq_time); + else + raise = 1; } raw_spin_unlock(&cpu_base->lock); } + + if (raise) + raise_softirq_irqoff(HRTIMER_SOFTIRQ); } /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1789 @ static enum hrtimer_restart hrtimer_wake void hrtimer_init_sleeper(struct hrtimer_sleeper *sl, struct task_struct *task) { sl->timer.function = hrtimer_wakeup; + sl->timer.irqsafe = 1; sl->task = task; } EXPORT_SYMBOL_GPL(hrtimer_init_sleeper); -static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mode) +static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mode, + unsigned long state) { hrtimer_init_sleeper(t, current); do { - set_current_state(TASK_INTERRUPTIBLE); + set_current_state(state); hrtimer_start_expires(&t->timer, mode); if (!hrtimer_active(&t->timer)) t->task = NULL; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1844 @ long __sched hrtimer_nanosleep_restart(s HRTIMER_MODE_ABS); hrtimer_set_expires_tv64(&t.timer, restart->nanosleep.expires); - if (do_nanosleep(&t, HRTIMER_MODE_ABS)) + /* cpu_chill() does not care about restart state. */ + if (do_nanosleep(&t, HRTIMER_MODE_ABS, TASK_INTERRUPTIBLE)) goto out; rmtp = restart->nanosleep.rmtp; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1862 @ out: return ret; } -long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp, - const enum hrtimer_mode mode, const clockid_t clockid) +static long +__hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp, + const enum hrtimer_mode mode, const clockid_t clockid, + unsigned long state) { struct restart_block *restart; struct hrtimer_sleeper t; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1878 @ long hrtimer_nanosleep(struct timespec * hrtimer_init_on_stack(&t.timer, clockid, mode); hrtimer_set_expires_range_ns(&t.timer, timespec_to_ktime(*rqtp), slack); - if (do_nanosleep(&t, mode)) + if (do_nanosleep(&t, mode, state)) goto out; /* Absolute timers do not update the rmtp value and restart: */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1905 @ out: return ret; } +long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp, + const enum hrtimer_mode mode, const clockid_t clockid) +{ + return __hrtimer_nanosleep(rqtp, rmtp, mode, clockid, TASK_INTERRUPTIBLE); +} + SYSCALL_DEFINE2(nanosleep, struct timespec __user *, rqtp, struct timespec __user *, rmtp) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1925 @ SYSCALL_DEFINE2(nanosleep, struct timesp return hrtimer_nanosleep(&tu, rmtp, HRTIMER_MODE_REL, CLOCK_MONOTONIC); } +#ifdef CONFIG_PREEMPT_RT_FULL +/* + * Sleep for 1 ms in hope whoever holds what we want will let it go. + */ +void cpu_chill(void) +{ + struct timespec tu = { + .tv_nsec = NSEC_PER_MSEC, + }; + unsigned int freeze_flag = current->flags & PF_NOFREEZE; + + current->flags |= PF_NOFREEZE; + __hrtimer_nanosleep(&tu, NULL, HRTIMER_MODE_REL, CLOCK_MONOTONIC, + TASK_UNINTERRUPTIBLE); + if (!freeze_flag) + current->flags &= ~PF_NOFREEZE; +} +EXPORT_SYMBOL(cpu_chill); +#endif + /* * Functions related to boot-time initialization: */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1956 @ static void init_hrtimers_cpu(int cpu) for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) { cpu_base->clock_base[i].cpu_base = cpu_base; timerqueue_init_head(&cpu_base->clock_base[i].active); + INIT_LIST_HEAD(&cpu_base->clock_base[i].expired); } hrtimer_init_hres(cpu_base); +#ifdef CONFIG_PREEMPT_RT_BASE + init_waitqueue_head(&cpu_base->wait); +#endif } #ifdef CONFIG_HOTPLUG_CPU @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2075 @ void __init hrtimers_init(void) hrtimer_cpu_notify(&hrtimers_nb, (unsigned long)CPU_UP_PREPARE, (void *)(long)smp_processor_id()); register_cpu_notifier(&hrtimers_nb); -#ifdef CONFIG_HIGH_RES_TIMERS open_softirq(HRTIMER_SOFTIRQ, run_hrtimer_softirq); -#endif } /** Index: linux-3.12.19-rt30/kernel/irq/handle.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/irq/handle.c +++ linux-3.12.19-rt30/kernel/irq/handle.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:135 @ static void irq_wake_thread(struct irq_d irqreturn_t handle_irq_event_percpu(struct irq_desc *desc, struct irqaction *action) { + struct pt_regs *regs = get_irq_regs(); + u64 ip = regs ? instruction_pointer(regs) : 0; irqreturn_t retval = IRQ_NONE; unsigned int flags = 0, irq = desc->irq_data.irq; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:177 @ handle_irq_event_percpu(struct irq_desc action = action->next; } while (action); - add_interrupt_randomness(irq, flags); +#ifndef CONFIG_PREEMPT_RT_FULL + add_interrupt_randomness(irq, flags, ip); +#else + desc->random_ip = ip; +#endif if (!noirqdebug) note_interrupt(irq, desc, retval); Index: linux-3.12.19-rt30/kernel/irq/manage.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/irq/manage.c +++ linux-3.12.19-rt30/kernel/irq/manage.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:25 @ #include "internals.h" #ifdef CONFIG_IRQ_FORCED_THREADING +# ifndef CONFIG_PREEMPT_RT_BASE __read_mostly bool force_irqthreads; static int __init setup_forced_irqthreads(char *arg) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:34 @ static int __init setup_forced_irqthread return 0; } early_param("threadirqs", setup_forced_irqthreads); +# endif #endif /** @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:167 @ int irq_do_set_affinity(struct irq_data return ret; } +#ifdef CONFIG_PREEMPT_RT_FULL +static void _irq_affinity_notify(struct irq_affinity_notify *notify); +static struct task_struct *set_affinity_helper; +static LIST_HEAD(affinity_list); +static DEFINE_RAW_SPINLOCK(affinity_list_lock); + +static int set_affinity_thread(void *unused) +{ + while (1) { + struct irq_affinity_notify *notify; + int empty; + + set_current_state(TASK_INTERRUPTIBLE); + + raw_spin_lock_irq(&affinity_list_lock); + empty = list_empty(&affinity_list); + raw_spin_unlock_irq(&affinity_list_lock); + + if (empty) + schedule(); + if (kthread_should_stop()) + break; + set_current_state(TASK_RUNNING); +try_next: + notify = NULL; + + raw_spin_lock_irq(&affinity_list_lock); + if (!list_empty(&affinity_list)) { + notify = list_first_entry(&affinity_list, + struct irq_affinity_notify, list); + list_del_init(¬ify->list); + } + raw_spin_unlock_irq(&affinity_list_lock); + + if (!notify) + continue; + _irq_affinity_notify(notify); + goto try_next; + } + return 0; +} + +static void init_helper_thread(void) +{ + if (set_affinity_helper) + return; + set_affinity_helper = kthread_run(set_affinity_thread, NULL, + "affinity-cb"); + WARN_ON(IS_ERR(set_affinity_helper)); +} +#else + +static inline void init_helper_thread(void) { } + +#endif + int irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask, bool force) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:242 @ int irq_set_affinity_locked(struct irq_d if (desc->affinity_notify) { kref_get(&desc->affinity_notify->kref); + +#ifdef CONFIG_PREEMPT_RT_FULL + raw_spin_lock(&affinity_list_lock); + if (list_empty(&desc->affinity_notify->list)) + list_add_tail(&affinity_list, + &desc->affinity_notify->list); + raw_spin_unlock(&affinity_list_lock); + wake_up_process(set_affinity_helper); +#else schedule_work(&desc->affinity_notify->work); +#endif } irqd_set(data, IRQD_AFFINITY_SET); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:287 @ int irq_set_affinity_hint(unsigned int i } EXPORT_SYMBOL_GPL(irq_set_affinity_hint); -static void irq_affinity_notify(struct work_struct *work) +static void _irq_affinity_notify(struct irq_affinity_notify *notify) { - struct irq_affinity_notify *notify = - container_of(work, struct irq_affinity_notify, work); struct irq_desc *desc = irq_to_desc(notify->irq); cpumask_var_t cpumask; unsigned long flags; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:310 @ out: kref_put(¬ify->kref, notify->release); } +static void irq_affinity_notify(struct work_struct *work) +{ + struct irq_affinity_notify *notify = + container_of(work, struct irq_affinity_notify, work); + _irq_affinity_notify(notify); +} + /** * irq_set_affinity_notifier - control notification of IRQ affinity changes * @irq: Interrupt for which to enable/disable notification @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:346 @ irq_set_affinity_notifier(unsigned int i notify->irq = irq; kref_init(¬ify->kref); INIT_WORK(¬ify->work, irq_affinity_notify); + INIT_LIST_HEAD(¬ify->list); + init_helper_thread(); } raw_spin_lock_irqsave(&desc->lock, flags); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:854 @ irq_forced_thread_fn(struct irq_desc *de local_bh_disable(); ret = action->thread_fn(action->irq, action->dev_id); irq_finalize_oneshot(desc, action); - local_bh_enable(); + /* + * Interrupts which have real time requirements can be set up + * to avoid softirq processing in the thread handler. This is + * safe as these interrupts do not raise soft interrupts. + */ + if (irq_settings_no_softirq_call(desc)) + _local_bh_enable(); + else + local_bh_enable(); return ret; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:945 @ static int irq_thread(void *data) if (action_ret == IRQ_HANDLED) atomic_inc(&desc->threads_handled); +#ifdef CONFIG_PREEMPT_RT_FULL + migrate_disable(); + add_interrupt_randomness(action->irq, 0, + desc->random_ip ^ (unsigned long) action); + migrate_enable(); +#endif wake_threads_waitq(desc); } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1213 @ __setup_irq(unsigned int irq, struct irq irqd_set(&desc->irq_data, IRQD_NO_BALANCING); } + if (new->flags & IRQF_NO_SOFTIRQ_CALL) + irq_settings_set_no_softirq_call(desc); + /* Set default affinity mask once everything is setup */ setup_affinity(irq, desc, mask); Index: linux-3.12.19-rt30/kernel/irq/settings.h =================================================================== --- linux-3.12.19-rt30.orig/kernel/irq/settings.h +++ linux-3.12.19-rt30/kernel/irq/settings.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:17 @ enum { _IRQ_NO_BALANCING = IRQ_NO_BALANCING, _IRQ_NESTED_THREAD = IRQ_NESTED_THREAD, _IRQ_PER_CPU_DEVID = IRQ_PER_CPU_DEVID, + _IRQ_NO_SOFTIRQ_CALL = IRQ_NO_SOFTIRQ_CALL, _IRQF_MODIFY_MASK = IRQF_MODIFY_MASK, }; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:30 @ enum { #define IRQ_NOAUTOEN GOT_YOU_MORON #define IRQ_NESTED_THREAD GOT_YOU_MORON #define IRQ_PER_CPU_DEVID GOT_YOU_MORON +#define IRQ_NO_SOFTIRQ_CALL GOT_YOU_MORON #undef IRQF_MODIFY_MASK #define IRQF_MODIFY_MASK GOT_YOU_MORON @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:41 @ irq_settings_clr_and_set(struct irq_desc desc->status_use_accessors |= (set & _IRQF_MODIFY_MASK); } +static inline bool irq_settings_no_softirq_call(struct irq_desc *desc) +{ + return desc->status_use_accessors & _IRQ_NO_SOFTIRQ_CALL; +} + +static inline void irq_settings_set_no_softirq_call(struct irq_desc *desc) +{ + desc->status_use_accessors |= _IRQ_NO_SOFTIRQ_CALL; +} + static inline bool irq_settings_is_per_cpu(struct irq_desc *desc) { return desc->status_use_accessors & _IRQ_PER_CPU; Index: linux-3.12.19-rt30/kernel/irq/spurious.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/irq/spurious.c +++ linux-3.12.19-rt30/kernel/irq/spurious.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:441 @ MODULE_PARM_DESC(noirqdebug, "Disable ir static int __init irqfixup_setup(char *str) { +#ifdef CONFIG_PREEMPT_RT_BASE + pr_warn("irqfixup boot option not supported w/ CONFIG_PREEMPT_RT_BASE\n"); + return 1; +#endif irqfixup = 1; printk(KERN_WARNING "Misrouted IRQ fixup support enabled.\n"); printk(KERN_WARNING "This may impact system performance.\n"); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:457 @ module_param(irqfixup, int, 0644); static int __init irqpoll_setup(char *str) { +#ifdef CONFIG_PREEMPT_RT_BASE + pr_warn("irqpoll boot option not supported w/ CONFIG_PREEMPT_RT_BASE\n"); + return 1; +#endif irqfixup = 2; printk(KERN_WARNING "Misrouted IRQ fixup and polling support " "enabled\n"); Index: linux-3.12.19-rt30/kernel/irq_work.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/irq_work.c +++ linux-3.12.19-rt30/kernel/irq_work.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:23 @ static DEFINE_PER_CPU(struct llist_head, irq_work_list); +#ifdef CONFIG_PREEMPT_RT_FULL +static DEFINE_PER_CPU(struct llist_head, hirq_work_list); +#endif static DEFINE_PER_CPU(int, irq_work_raised); /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:54 @ static bool irq_work_claim(struct irq_wo return true; } +#ifdef CONFIG_PREEMPT_RT_FULL +void arch_irq_work_raise(void) +#else void __weak arch_irq_work_raise(void) +#endif { /* * Lame architectures will get the timer tick callback @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:80 @ void irq_work_queue(struct irq_work *wor /* Queue the entry and raise the IPI if needed. */ preempt_disable(); - llist_add(&work->llnode, &__get_cpu_var(irq_work_list)); - +#ifdef CONFIG_PREEMPT_RT_FULL + if (work->flags & IRQ_WORK_HARD_IRQ) + llist_add(&work->llnode, &__get_cpu_var(hirq_work_list)); + else +#endif + llist_add(&work->llnode, &__get_cpu_var(irq_work_list)); /* * If the work is not "lazy" or the tick is stopped, raise the irq * work interrupt (if supported by the arch), otherwise, just wait @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:129 @ static void __irq_work_run(void) __this_cpu_write(irq_work_raised, 0); barrier(); - this_list = &__get_cpu_var(irq_work_list); +#ifdef CONFIG_PREEMPT_RT_FULL + if (in_irq()) + this_list = &__get_cpu_var(hirq_work_list); + else +#endif + this_list = &__get_cpu_var(irq_work_list); if (llist_empty(this_list)) return; +#ifndef CONFIG_PREEMPT_RT_FULL BUG_ON(!irqs_disabled()); - +#endif llnode = llist_del_all(this_list); while (llnode != NULL) { work = llist_entry(llnode, struct irq_work, llnode); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:172 @ static void __irq_work_run(void) */ void irq_work_run(void) { +#ifndef CONFIG_PREEMPT_RT_FULL BUG_ON(!in_irq()); +#endif __irq_work_run(); } EXPORT_SYMBOL_GPL(irq_work_run); Index: linux-3.12.19-rt30/kernel/itimer.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/itimer.c +++ linux-3.12.19-rt30/kernel/itimer.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:216 @ again: /* We are sharing ->siglock with it_real_fn() */ if (hrtimer_try_to_cancel(timer) < 0) { spin_unlock_irq(&tsk->sighand->siglock); + hrtimer_wait_for_timer(&tsk->signal->real_timer); goto again; } expires = timeval_to_ktime(value->it_value); Index: linux-3.12.19-rt30/kernel/ksysfs.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/ksysfs.c +++ linux-3.12.19-rt30/kernel/ksysfs.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:135 @ KERNEL_ATTR_RO(vmcoreinfo); #endif /* CONFIG_KEXEC */ +#if defined(CONFIG_PREEMPT_RT_FULL) +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) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:209 @ static struct attribute * kernel_attrs[] &vmcoreinfo_attr.attr, #endif &rcu_expedited_attr.attr, +#ifdef CONFIG_PREEMPT_RT_FULL + &realtime_attr.attr, +#endif NULL }; Index: linux-3.12.19-rt30/kernel/lglock.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/lglock.c +++ linux-3.12.19-rt30/kernel/lglock.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:7 @ #include <linux/cpu.h> #include <linux/string.h> +#ifndef CONFIG_PREEMPT_RT_FULL +# define lg_lock_ptr arch_spinlock_t +# define lg_do_lock(l) arch_spin_lock(l) +# define lg_do_unlock(l) arch_spin_unlock(l) +#else +# define lg_lock_ptr struct rt_mutex +# define lg_do_lock(l) __rt_spin_lock(l) +# define lg_do_unlock(l) __rt_spin_unlock(l) +#endif /* * Note there is no uninit, so lglocks cannot be defined in * modules (but it's fine to use them from there) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:24 @ void lg_lock_init(struct lglock *lg, char *name) { +#ifdef CONFIG_PREEMPT_RT_FULL + int i; + + for_each_possible_cpu(i) { + struct rt_mutex *lock = per_cpu_ptr(lg->lock, i); + + rt_mutex_init(lock); + } +#endif LOCKDEP_INIT_MAP(&lg->lock_dep_map, name, &lg->lock_key, 0); } EXPORT_SYMBOL(lg_lock_init); void lg_local_lock(struct lglock *lg) { - arch_spinlock_t *lock; + lg_lock_ptr *lock; - preempt_disable(); + migrate_disable(); lock_acquire_shared(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_); lock = this_cpu_ptr(lg->lock); - arch_spin_lock(lock); + lg_do_lock(lock); } EXPORT_SYMBOL(lg_local_lock); void lg_local_unlock(struct lglock *lg) { - arch_spinlock_t *lock; + lg_lock_ptr *lock; lock_release(&lg->lock_dep_map, 1, _RET_IP_); lock = this_cpu_ptr(lg->lock); - arch_spin_unlock(lock); - preempt_enable(); + lg_do_unlock(lock); + migrate_enable(); } EXPORT_SYMBOL(lg_local_unlock); void lg_local_lock_cpu(struct lglock *lg, int cpu) { - arch_spinlock_t *lock; + lg_lock_ptr *lock; - preempt_disable(); + preempt_disable_nort(); lock_acquire_shared(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_); lock = per_cpu_ptr(lg->lock, cpu); - arch_spin_lock(lock); + lg_do_lock(lock); } EXPORT_SYMBOL(lg_local_lock_cpu); void lg_local_unlock_cpu(struct lglock *lg, int cpu) { - arch_spinlock_t *lock; + lg_lock_ptr *lock; lock_release(&lg->lock_dep_map, 1, _RET_IP_); lock = per_cpu_ptr(lg->lock, cpu); - arch_spin_unlock(lock); - preempt_enable(); + lg_do_unlock(lock); + preempt_enable_nort(); } EXPORT_SYMBOL(lg_local_unlock_cpu); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:85 @ void lg_global_lock(struct lglock *lg) { int i; - preempt_disable(); + preempt_disable_nort(); lock_acquire_exclusive(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_); for_each_possible_cpu(i) { - arch_spinlock_t *lock; + lg_lock_ptr *lock; lock = per_cpu_ptr(lg->lock, i); - arch_spin_lock(lock); + lg_do_lock(lock); } } EXPORT_SYMBOL(lg_global_lock); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:101 @ void lg_global_unlock(struct lglock *lg) lock_release(&lg->lock_dep_map, 1, _RET_IP_); for_each_possible_cpu(i) { - arch_spinlock_t *lock; + lg_lock_ptr *lock; lock = per_cpu_ptr(lg->lock, i); - arch_spin_unlock(lock); + lg_do_unlock(lock); } - preempt_enable(); + preempt_enable_nort(); } EXPORT_SYMBOL(lg_global_unlock); Index: linux-3.12.19-rt30/kernel/lockdep.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/lockdep.c +++ linux-3.12.19-rt30/kernel/lockdep.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:3544 @ static void check_flags(unsigned long fl } } +#ifndef CONFIG_PREEMPT_RT_FULL /* * We dont accurately track softirq state in e.g. * hardirq contexts (such as on 4KSTACKS), so only @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:3559 @ static void check_flags(unsigned long fl DEBUG_LOCKS_WARN_ON(!current->softirqs_enabled); } } +#endif if (!debug_locks) print_irqtrace_events(current); Index: linux-3.12.19-rt30/kernel/panic.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/panic.c +++ linux-3.12.19-rt30/kernel/panic.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:371 @ static u64 oops_id; static int init_oops_id(void) { +#ifndef CONFIG_PREEMPT_RT_FULL if (!oops_id) get_random_bytes(&oops_id, sizeof(oops_id)); else +#endif oops_id++; return 0; Index: linux-3.12.19-rt30/kernel/posix-cpu-timers.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/posix-cpu-timers.c +++ linux-3.12.19-rt30/kernel/posix-cpu-timers.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:6 @ */ #include <linux/sched.h> +#include <linux/sched/rt.h> #include <linux/posix-timers.h> #include <linux/errno.h> #include <linux/math64.h> @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:667 @ static int posix_cpu_timer_set(struct k_ /* * Disarm any old timer after extracting its expiry time. */ - BUG_ON(!irqs_disabled()); + BUG_ON_NONRT(!irqs_disabled()); ret = 0; old_incr = timer->it.cpu.incr; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1114 @ void posix_cpu_timer_schedule(struct k_i /* * Now re-arm for the new expiry time. */ - BUG_ON(!irqs_disabled()); + BUG_ON_NONRT(!irqs_disabled()); arm_timer(timer); spin_unlock(&p->sighand->siglock); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1181 @ static inline int fastpath_timer_check(s sig = tsk->signal; if (sig->cputimer.running) { struct task_cputime group_sample; + unsigned long flags; - raw_spin_lock(&sig->cputimer.lock); + raw_spin_lock_irqsave(&sig->cputimer.lock, flags); group_sample = sig->cputimer.cputime; - raw_spin_unlock(&sig->cputimer.lock); + raw_spin_unlock_irqrestore(&sig->cputimer.lock, flags); if (task_cputime_expired(&group_sample, &sig->cputime_expires)) return 1; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1199 @ static inline int fastpath_timer_check(s * already updated our counts. We need to check if any timers fire now. * Interrupts are disabled. */ -void run_posix_cpu_timers(struct task_struct *tsk) +static void __run_posix_cpu_timers(struct task_struct *tsk) { LIST_HEAD(firing); struct k_itimer *timer, *next; unsigned long flags; - BUG_ON(!irqs_disabled()); + BUG_ON_NONRT(!irqs_disabled()); /* * The fast path checks that there are no expired thread or thread @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1270 @ void run_posix_cpu_timers(struct task_st posix_cpu_timer_kick_nohz(); } +#ifdef CONFIG_PREEMPT_RT_BASE +#include <linux/kthread.h> +#include <linux/cpu.h> +DEFINE_PER_CPU(struct task_struct *, posix_timer_task); +DEFINE_PER_CPU(struct task_struct *, posix_timer_tasklist); + +static int posix_cpu_timers_thread(void *data) +{ + int cpu = (long)data; + + BUG_ON(per_cpu(posix_timer_task,cpu) != current); + + while (!kthread_should_stop()) { + struct task_struct *tsk = NULL; + struct task_struct *next = NULL; + + if (cpu_is_offline(cpu)) + goto wait_to_die; + + /* grab task list */ + raw_local_irq_disable(); + tsk = per_cpu(posix_timer_tasklist, cpu); + per_cpu(posix_timer_tasklist, cpu) = NULL; + raw_local_irq_enable(); + + /* its possible the list is empty, just return */ + if (!tsk) { + set_current_state(TASK_INTERRUPTIBLE); + schedule(); + __set_current_state(TASK_RUNNING); + continue; + } + + /* Process task list */ + while (1) { + /* save next */ + next = tsk->posix_timer_list; + + /* run the task timers, clear its ptr and + * unreference it + */ + __run_posix_cpu_timers(tsk); + tsk->posix_timer_list = NULL; + put_task_struct(tsk); + + /* check if this is the last on the list */ + if (next == tsk) + break; + tsk = next; + } + } + return 0; + +wait_to_die: + /* Wait for kthread_stop */ + set_current_state(TASK_INTERRUPTIBLE); + while (!kthread_should_stop()) { + schedule(); + set_current_state(TASK_INTERRUPTIBLE); + } + __set_current_state(TASK_RUNNING); + return 0; +} + +static inline int __fastpath_timer_check(struct task_struct *tsk) +{ + /* tsk == current, ensure it is safe to use ->signal/sighand */ + if (unlikely(tsk->exit_state)) + return 0; + + if (!task_cputime_zero(&tsk->cputime_expires)) + return 1; + + if (!task_cputime_zero(&tsk->signal->cputime_expires)) + return 1; + + return 0; +} + +void run_posix_cpu_timers(struct task_struct *tsk) +{ + unsigned long cpu = smp_processor_id(); + struct task_struct *tasklist; + + BUG_ON(!irqs_disabled()); + if(!per_cpu(posix_timer_task, cpu)) + return; + /* get per-cpu references */ + tasklist = per_cpu(posix_timer_tasklist, cpu); + + /* check to see if we're already queued */ + if (!tsk->posix_timer_list && __fastpath_timer_check(tsk)) { + get_task_struct(tsk); + if (tasklist) { + tsk->posix_timer_list = tasklist; + } else { + /* + * The list is terminated by a self-pointing + * task_struct + */ + tsk->posix_timer_list = tsk; + } + per_cpu(posix_timer_tasklist, cpu) = tsk; + + wake_up_process(per_cpu(posix_timer_task, cpu)); + } +} + +/* + * posix_cpu_thread_call - callback that gets triggered when a CPU is added. + * Here we can start up the necessary migration thread for the new CPU. + */ +static int posix_cpu_thread_call(struct notifier_block *nfb, + unsigned long action, void *hcpu) +{ + int cpu = (long)hcpu; + struct task_struct *p; + struct sched_param param; + + switch (action) { + case CPU_UP_PREPARE: + p = kthread_create(posix_cpu_timers_thread, hcpu, + "posixcputmr/%d",cpu); + if (IS_ERR(p)) + return NOTIFY_BAD; + p->flags |= PF_NOFREEZE; + kthread_bind(p, cpu); + /* Must be high prio to avoid getting starved */ + param.sched_priority = MAX_RT_PRIO-1; + sched_setscheduler(p, SCHED_FIFO, ¶m); + per_cpu(posix_timer_task,cpu) = p; + break; + case CPU_ONLINE: + /* Strictly unneccessary, as first user will wake it. */ + wake_up_process(per_cpu(posix_timer_task,cpu)); + break; +#ifdef CONFIG_HOTPLUG_CPU + case CPU_UP_CANCELED: + /* Unbind it from offline cpu so it can run. Fall thru. */ + kthread_bind(per_cpu(posix_timer_task, cpu), + cpumask_any(cpu_online_mask)); + kthread_stop(per_cpu(posix_timer_task,cpu)); + per_cpu(posix_timer_task,cpu) = NULL; + break; + case CPU_DEAD: + kthread_stop(per_cpu(posix_timer_task,cpu)); + per_cpu(posix_timer_task,cpu) = NULL; + break; +#endif + } + return NOTIFY_OK; +} + +/* Register at highest priority so that task migration (migrate_all_tasks) + * happens before everything else. + */ +static struct notifier_block posix_cpu_thread_notifier = { + .notifier_call = posix_cpu_thread_call, + .priority = 10 +}; + +static int __init posix_cpu_thread_init(void) +{ + void *hcpu = (void *)(long)smp_processor_id(); + /* Start one for boot CPU. */ + unsigned long cpu; + + /* init the per-cpu posix_timer_tasklets */ + for_each_possible_cpu(cpu) + per_cpu(posix_timer_tasklist, cpu) = NULL; + + posix_cpu_thread_call(&posix_cpu_thread_notifier, CPU_UP_PREPARE, hcpu); + posix_cpu_thread_call(&posix_cpu_thread_notifier, CPU_ONLINE, hcpu); + register_cpu_notifier(&posix_cpu_thread_notifier); + return 0; +} +early_initcall(posix_cpu_thread_init); +#else /* CONFIG_PREEMPT_RT_BASE */ +void run_posix_cpu_timers(struct task_struct *tsk) +{ + __run_posix_cpu_timers(tsk); +} +#endif /* CONFIG_PREEMPT_RT_BASE */ + /* * Set one of the process-wide special case CPU timers or RLIMIT_CPU. * The tsk->sighand->siglock must be held by the caller. Index: linux-3.12.19-rt30/kernel/posix-timers.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/posix-timers.c +++ linux-3.12.19-rt30/kernel/posix-timers.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:500 @ static enum hrtimer_restart posix_timer_ static struct pid *good_sigevent(sigevent_t * event) { struct task_struct *rtn = current->group_leader; + int sig = event->sigev_signo; if ((event->sigev_notify & SIGEV_THREAD_ID ) && (!(rtn = find_task_by_vpid(event->sigev_notify_thread_id)) || @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:509 @ static struct pid *good_sigevent(sigeven return NULL; if (((event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) && - ((event->sigev_signo <= 0) || (event->sigev_signo > SIGRTMAX))) + (sig <= 0 || sig > SIGRTMAX || sig_kernel_only(sig) || + sig_kernel_coredump(sig))) return NULL; return task_pid(rtn); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:821 @ SYSCALL_DEFINE1(timer_getoverrun, timer_ return overrun; } +/* + * Protected by RCU! + */ +static void timer_wait_for_callback(struct k_clock *kc, struct k_itimer *timr) +{ +#ifdef CONFIG_PREEMPT_RT_FULL + if (kc->timer_set == common_timer_set) + hrtimer_wait_for_timer(&timr->it.real.timer); + else + /* FIXME: Whacky hack for posix-cpu-timers */ + schedule_timeout(1); +#endif +} + /* Set a POSIX.1b interval timer. */ /* timr->it_lock is taken. */ static int @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:912 @ retry: if (!timr) return -EINVAL; + rcu_read_lock(); kc = clockid_to_kclock(timr->it_clock); if (WARN_ON_ONCE(!kc || !kc->timer_set)) error = -EINVAL; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:921 @ retry: unlock_timer(timr, flag); if (error == TIMER_RETRY) { + timer_wait_for_callback(kc, timr); rtn = NULL; // We already got the old time... + rcu_read_unlock(); goto retry; } + rcu_read_unlock(); if (old_setting && !error && copy_to_user(old_setting, &old_spec, sizeof (old_spec))) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:964 @ retry_delete: if (!timer) return -EINVAL; + rcu_read_lock(); if (timer_delete_hook(timer) == TIMER_RETRY) { unlock_timer(timer, flags); + timer_wait_for_callback(clockid_to_kclock(timer->it_clock), + timer); + rcu_read_unlock(); goto retry_delete; } + rcu_read_unlock(); spin_lock(¤t->sighand->siglock); list_del(&timer->list); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:998 @ static void itimer_delete(struct k_itime retry_delete: spin_lock_irqsave(&timer->it_lock, flags); + /* On RT we can race with a deletion */ + if (!timer->it_signal) { + unlock_timer(timer, flags); + return; + } + if (timer_delete_hook(timer) == TIMER_RETRY) { + rcu_read_lock(); unlock_timer(timer, flags); + timer_wait_for_callback(clockid_to_kclock(timer->it_clock), + timer); + rcu_read_unlock(); goto retry_delete; } list_del(&timer->list); Index: linux-3.12.19-rt30/kernel/power/hibernate.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/power/hibernate.c +++ linux-3.12.19-rt30/kernel/power/hibernate.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:278 @ static int create_image(int platform_mod local_irq_disable(); + system_state = SYSTEM_SUSPEND; + error = syscore_suspend(); if (error) { printk(KERN_ERR "PM: Some system devices failed to power down, " @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:307 @ static int create_image(int platform_mod syscore_resume(); Enable_irqs: + system_state = SYSTEM_RUNNING; local_irq_enable(); Enable_cpus: @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:433 @ static int resume_target_kernel(bool pla goto Enable_cpus; local_irq_disable(); + system_state = SYSTEM_SUSPEND; error = syscore_suspend(); if (error) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:467 @ static int resume_target_kernel(bool pla syscore_resume(); Enable_irqs: + system_state = SYSTEM_RUNNING; local_irq_enable(); Enable_cpus: @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:550 @ int hibernation_platform_enter(void) goto Platform_finish; local_irq_disable(); + system_state = SYSTEM_SUSPEND; syscore_suspend(); if (pm_wakeup_pending()) { error = -EAGAIN; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:563 @ int hibernation_platform_enter(void) Power_up: syscore_resume(); + system_state = SYSTEM_RUNNING; local_irq_enable(); enable_nonboot_cpus(); Index: linux-3.12.19-rt30/kernel/power/suspend.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/power/suspend.c +++ linux-3.12.19-rt30/kernel/power/suspend.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:213 @ static int suspend_enter(suspend_state_t arch_suspend_disable_irqs(); BUG_ON(!irqs_disabled()); + system_state = SYSTEM_SUSPEND; + error = syscore_suspend(); if (!error) { *wakeup = pm_wakeup_pending(); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:225 @ static int suspend_enter(suspend_state_t syscore_resume(); } + system_state = SYSTEM_RUNNING; + arch_suspend_enable_irqs(); BUG_ON(irqs_disabled()); Index: linux-3.12.19-rt30/kernel/printk/printk.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/printk/printk.c +++ linux-3.12.19-rt30/kernel/printk/printk.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1032 @ static int syslog_print_all(char __user { char *text; int len = 0; + int attempts = 0; text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL); if (!text) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1044 @ static int syslog_print_all(char __user u64 seq; u32 idx; enum log_flags prev; - + int num_msg; +try_again: + attempts++; + if (attempts > 10) { + len = -EBUSY; + goto out; + } + num_msg = 0; if (clear_seq < log_first_seq) { /* messages are gone, move to first available one */ clear_seq = log_first_seq; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1072 @ static int syslog_print_all(char __user prev = msg->flags; idx = log_next(idx); seq++; + num_msg++; + if (num_msg > 5) { + num_msg = 0; + raw_spin_unlock_irq(&logbuf_lock); + raw_spin_lock_irq(&logbuf_lock); + if (clear_seq < log_first_seq) + goto try_again; + } } /* move first record forward until length fits into the buffer */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1093 @ static int syslog_print_all(char __user prev = msg->flags; idx = log_next(idx); seq++; + num_msg++; + if (num_msg > 5) { + num_msg = 0; + raw_spin_unlock_irq(&logbuf_lock); + raw_spin_lock_irq(&logbuf_lock); + if (clear_seq < log_first_seq) + goto try_again; + } } /* last message fitting into this dump */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1141 @ static int syslog_print_all(char __user clear_seq = log_next_seq; clear_idx = log_next_idx; } +out: raw_spin_unlock_irq(&logbuf_lock); kfree(text); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1299 @ static void call_console_drivers(int lev if (!console_drivers) return; + migrate_disable(); for_each_console(con) { if (exclusive_console && con != exclusive_console) continue; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1312 @ static void call_console_drivers(int lev continue; con->write(con, text, len); } + migrate_enable(); } /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1372 @ static inline int can_use_console(unsign * interrupts disabled. It should return with 'lockbuf_lock' * released but interrupts still disabled. */ -static int console_trylock_for_printk(unsigned int cpu) +static int console_trylock_for_printk(unsigned int cpu, unsigned long flags) __releases(&logbuf_lock) { int retval = 0, wake = 0; +#ifdef CONFIG_PREEMPT_RT_FULL + int lock = !early_boot_irqs_disabled && !irqs_disabled_flags(flags) && + (preempt_count() <= 1); +#else + int lock = 1; +#endif - if (console_trylock()) { + if (lock && console_trylock()) { retval = 1; /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1523 @ static size_t cont_print_text(char *text return textlen; } +#ifdef CONFIG_EARLY_PRINTK +struct console *early_console; + +void early_vprintk(const char *fmt, va_list ap) +{ + if (early_console) { + char buf[512]; + int n = vscnprintf(buf, sizeof(buf), fmt, ap); + + early_console->write(early_console, buf, n); + } +} + +asmlinkage void early_printk(const char *fmt, ...) +{ + va_list ap; + + va_start(ap, fmt); + early_vprintk(fmt, ap); + va_end(ap); +} + +/* + * This is independent of any log levels - a global + * kill switch that turns off all of printk. + * + * Used by the NMI watchdog if early-printk is enabled. + */ +static bool __read_mostly printk_killswitch; + +static int __init force_early_printk_setup(char *str) +{ + printk_killswitch = true; + return 0; +} +early_param("force_early_printk", force_early_printk_setup); + +void printk_kill(void) +{ + printk_killswitch = true; +} + +static int forced_early_printk(const char *fmt, va_list ap) +{ + if (!printk_killswitch) + return 0; + early_vprintk(fmt, ap); + return 1; +} +#else +static inline int forced_early_printk(const char *fmt, va_list ap) +{ + return 0; +} +#endif + asmlinkage int vprintk_emit(int facility, int level, const char *dict, size_t dictlen, const char *fmt, va_list args) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1592 @ asmlinkage int vprintk_emit(int facility int this_cpu; int printed_len = 0; + /* + * Fall back to early_printk if a debugging subsystem has + * killed printk output + */ + if (unlikely(forced_early_printk(fmt, args))) + return 1; + boot_delay_msec(level); printk_delay(); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1718 @ asmlinkage int vprintk_emit(int facility * The console_trylock_for_printk() function will release 'logbuf_lock' * regardless of whether it actually gets the console semaphore or not. */ - if (console_trylock_for_printk(this_cpu)) + if (console_trylock_for_printk(this_cpu, flags)) { +#ifndef CONFIG_PREEMPT_RT_FULL + console_unlock(); +#else + raw_local_irq_restore(flags); console_unlock(); + raw_local_irq_save(flags); +#endif + } lockdep_on(); out_restore_irqs: @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1828 @ static size_t cont_print_text(char *text #endif /* CONFIG_PRINTK */ -#ifdef CONFIG_EARLY_PRINTK -struct console *early_console; - -void early_vprintk(const char *fmt, va_list ap) -{ - if (early_console) { - char buf[512]; - int n = vscnprintf(buf, sizeof(buf), fmt, ap); - - early_console->write(early_console, buf, n); - } -} - -asmlinkage void early_printk(const char *fmt, ...) -{ - va_list ap; - - va_start(ap, fmt); - early_vprintk(fmt, ap); - va_end(ap); -} -#endif - static int __add_preferred_console(char *name, int idx, char *options, char *brl_options) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2068 @ static void console_cont_flush(char *tex goto out; len = cont_print_text(text, size); +#ifndef CONFIG_PREEMPT_RT_FULL raw_spin_unlock(&logbuf_lock); stop_critical_timings(); call_console_drivers(cont.level, text, len); start_critical_timings(); local_irq_restore(flags); +#else + raw_spin_unlock_irqrestore(&logbuf_lock, flags); + call_console_drivers(cont.level, text, len); +#endif return; out: raw_spin_unlock_irqrestore(&logbuf_lock, flags); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2160 @ skip: console_idx = log_next(console_idx); console_seq++; console_prev = msg->flags; - raw_spin_unlock(&logbuf_lock); +#ifndef CONFIG_PREEMPT_RT_FULL + raw_spin_unlock(&logbuf_lock); stop_critical_timings(); /* don't trace print latency */ call_console_drivers(level, text, len); start_critical_timings(); local_irq_restore(flags); +#else + raw_spin_unlock_irqrestore(&logbuf_lock, flags); + call_console_drivers(level, text, len); +#endif } console_locked = 0; mutex_release(&console_lock_dep_map, 1, _RET_IP_); Index: linux-3.12.19-rt30/kernel/ptrace.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/ptrace.c +++ linux-3.12.19-rt30/kernel/ptrace.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:138 @ static bool ptrace_freeze_traced(struct spin_lock_irq(&task->sighand->siglock); if (task_is_traced(task) && !__fatal_signal_pending(task)) { - task->state = __TASK_TRACED; + raw_spin_lock_irq(&task->pi_lock); + if (task->state & __TASK_TRACED) + task->state = __TASK_TRACED; + else + task->saved_state = __TASK_TRACED; + raw_spin_unlock_irq(&task->pi_lock); ret = true; } spin_unlock_irq(&task->sighand->siglock); Index: linux-3.12.19-rt30/kernel/rcupdate.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/rcupdate.c +++ linux-3.12.19-rt30/kernel/rcupdate.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:132 @ int notrace debug_lockdep_rcu_enabled(vo } EXPORT_SYMBOL_GPL(debug_lockdep_rcu_enabled); +#ifndef CONFIG_PREEMPT_RT_FULL /** * rcu_read_lock_bh_held() - might we be in RCU-bh read-side critical section? * @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:159 @ int rcu_read_lock_bh_held(void) return in_softirq() || irqs_disabled(); } EXPORT_SYMBOL_GPL(rcu_read_lock_bh_held); +#endif #endif /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */ Index: linux-3.12.19-rt30/kernel/rcutiny.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/rcutiny.c +++ linux-3.12.19-rt30/kernel/rcutiny.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:372 @ void call_rcu_sched(struct rcu_head *hea } EXPORT_SYMBOL_GPL(call_rcu_sched); +#ifndef CONFIG_PREEMPT_RT_FULL /* * Post an RCU bottom-half callback to be invoked after any subsequent * quiescent state. @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:382 @ void call_rcu_bh(struct rcu_head *head, __call_rcu(head, func, &rcu_bh_ctrlblk); } EXPORT_SYMBOL_GPL(call_rcu_bh); +#endif void rcu_init(void) { Index: linux-3.12.19-rt30/kernel/rcutree.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/rcutree.c +++ linux-3.12.19-rt30/kernel/rcutree.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:58 @ #include <linux/random.h> #include <linux/ftrace_event.h> #include <linux/suspend.h> +#include <linux/delay.h> +#include <linux/gfp.h> +#include <linux/oom.h> +#include <linux/smpboot.h> +#include "time/tick-internal.h" #include "rcutree.h" #include <trace/events/rcu.h> @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:153 @ EXPORT_SYMBOL_GPL(rcu_scheduler_active); */ static int rcu_scheduler_fully_active __read_mostly; -#ifdef CONFIG_RCU_BOOST - /* * Control variables for per-CPU and per-rcu_node kthreads. These * handle all flavors of RCU. @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:162 @ DEFINE_PER_CPU(unsigned int, rcu_cpu_kth DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_loops); DEFINE_PER_CPU(char, rcu_cpu_has_work); -#endif /* #ifdef CONFIG_RCU_BOOST */ - static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu); static void invoke_rcu_core(void); static void invoke_rcu_callbacks(struct rcu_state *rsp, struct rcu_data *rdp); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:203 @ void rcu_sched_qs(int cpu) rdp->passed_quiesce = 1; } +#ifdef CONFIG_PREEMPT_RT_FULL +static void rcu_preempt_qs(int cpu); + +void rcu_bh_qs(int cpu) +{ + unsigned long flags; + + /* Callers to this function, rcu_preempt_qs(), must disable irqs. */ + local_irq_save(flags); + rcu_preempt_qs(cpu); + local_irq_restore(flags); +} +#else void rcu_bh_qs(int cpu) { struct rcu_data *rdp = &per_cpu(rcu_bh_data, cpu); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:224 @ void rcu_bh_qs(int cpu) trace_rcu_grace_period(TPS("rcu_bh"), rdp->gpnum, TPS("cpuqs")); rdp->passed_quiesce = 1; } +#endif /* * Note a context switch. This is a quiescent state for RCU-sched, @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:281 @ long rcu_batches_completed_sched(void) } EXPORT_SYMBOL_GPL(rcu_batches_completed_sched); +#ifndef CONFIG_PREEMPT_RT_FULL /* * Return the number of RCU BH batches processed thus far for debug & stats. */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:299 @ void rcu_bh_force_quiescent_state(void) force_quiescent_state(&rcu_bh_state); } EXPORT_SYMBOL_GPL(rcu_bh_force_quiescent_state); +#endif /* * Record the number of times rcutorture tests have been initiated and @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1491 @ static int __noreturn rcu_gp_kthread(voi /* Handle grace-period start. */ for (;;) { - wait_event_interruptible(rsp->gp_wq, + swait_event_interruptible(rsp->gp_wq, rsp->gp_flags & RCU_GP_FLAG_INIT); if ((rsp->gp_flags & RCU_GP_FLAG_INIT) && @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1510 @ static int __noreturn rcu_gp_kthread(voi } for (;;) { rsp->jiffies_force_qs = jiffies + j; - ret = wait_event_interruptible_timeout(rsp->gp_wq, + ret = swait_event_interruptible_timeout(rsp->gp_wq, (rsp->gp_flags & RCU_GP_FLAG_FQS) || (!ACCESS_ONCE(rnp->qsmask) && !rcu_preempt_blocked_readers_cgp(rnp)), @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1548 @ static void rsp_wakeup(struct irq_work * struct rcu_state *rsp = container_of(work, struct rcu_state, wakeup_work); /* Wake up rcu_gp_kthread() to start the grace period. */ - wake_up(&rsp->gp_wq); + swait_wake(&rsp->gp_wq); } /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1622 @ static void rcu_report_qs_rsp(struct rcu { WARN_ON_ONCE(!rcu_gp_in_progress(rsp)); raw_spin_unlock_irqrestore(&rcu_get_root(rsp)->lock, flags); - wake_up(&rsp->gp_wq); /* Memory barrier implied by wake_up() path. */ + swait_wake(&rsp->gp_wq); /* Memory barrier implied by wake_up() path. */ } /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2192 @ static void force_quiescent_state(struct } rsp->gp_flags |= RCU_GP_FLAG_FQS; raw_spin_unlock_irqrestore(&rnp_old->lock, flags); - wake_up(&rsp->gp_wq); /* Memory barrier implied by wake_up() path. */ + /* Memory barrier implied by wake_up() path. */ + swait_wake(&rsp->gp_wq); } /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2230 @ __rcu_process_callbacks(struct rcu_state /* * Do RCU core processing for the current CPU. */ -static void rcu_process_callbacks(struct softirq_action *unused) +static void rcu_process_callbacks(void) { struct rcu_state *rsp; if (cpu_is_offline(smp_processor_id())) return; - trace_rcu_utilization(TPS("Start RCU core")); for_each_rcu_flavor(rsp) __rcu_process_callbacks(rsp); - trace_rcu_utilization(TPS("End RCU core")); } /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2251 @ static void invoke_rcu_callbacks(struct { if (unlikely(!ACCESS_ONCE(rcu_scheduler_fully_active))) return; - if (likely(!rsp->boost)) { - rcu_do_batch(rsp, rdp); + rcu_do_batch(rsp, rdp); +} + +static void rcu_wake_cond(struct task_struct *t, int status) +{ + /* + * If the thread is yielding, only wake it when this + * is invoked from idle + */ + if (t && (status != RCU_KTHREAD_YIELDING || is_idle_task(current))) + wake_up_process(t); +} + +/* + * Wake up this CPU's rcuc kthread to do RCU core processing. + */ +static void invoke_rcu_core(void) +{ + unsigned long flags; + struct task_struct *t; + + if (!cpu_online(smp_processor_id())) return; + local_irq_save(flags); + __this_cpu_write(rcu_cpu_has_work, 1); + t = __this_cpu_read(rcu_cpu_kthread_task); + if (t != NULL && current != t) + rcu_wake_cond(t, __this_cpu_read(rcu_cpu_kthread_status)); + local_irq_restore(flags); +} + +static void rcu_cpu_kthread_park(unsigned int cpu) +{ + per_cpu(rcu_cpu_kthread_status, cpu) = RCU_KTHREAD_OFFCPU; +} + +static int rcu_cpu_kthread_should_run(unsigned int cpu) +{ + return __this_cpu_read(rcu_cpu_has_work); +} + +/* + * Per-CPU kernel thread that invokes RCU callbacks. This replaces the + * RCU softirq used in flavors and configurations of RCU that do not + * support RCU priority boosting. + */ +static void rcu_cpu_kthread(unsigned int cpu) +{ + unsigned int *statusp = &__get_cpu_var(rcu_cpu_kthread_status); + char work, *workp = &__get_cpu_var(rcu_cpu_has_work); + int spincnt; + + for (spincnt = 0; spincnt < 10; spincnt++) { + trace_rcu_utilization(TPS("Start CPU kthread@rcu_wait")); + local_bh_disable(); + *statusp = RCU_KTHREAD_RUNNING; + this_cpu_inc(rcu_cpu_kthread_loops); + local_irq_disable(); + work = *workp; + *workp = 0; + local_irq_enable(); + if (work) + rcu_process_callbacks(); + local_bh_enable(); + if (*workp == 0) { + trace_rcu_utilization(TPS("End CPU kthread@rcu_wait")); + *statusp = RCU_KTHREAD_WAITING; + return; + } } - invoke_rcu_callbacks_kthread(); + *statusp = RCU_KTHREAD_YIELDING; + trace_rcu_utilization(TPS("Start CPU kthread@rcu_yield")); + schedule_timeout_interruptible(2); + trace_rcu_utilization(TPS("End CPU kthread@rcu_yield")); + *statusp = RCU_KTHREAD_WAITING; } -static void invoke_rcu_core(void) +static struct smp_hotplug_thread rcu_cpu_thread_spec = { + .store = &rcu_cpu_kthread_task, + .thread_should_run = rcu_cpu_kthread_should_run, + .thread_fn = rcu_cpu_kthread, + .thread_comm = "rcuc/%u", + .setup = rcu_cpu_kthread_setup, + .park = rcu_cpu_kthread_park, +}; + +/* + * Spawn per-CPU RCU core processing kthreads. + */ +static int __init rcu_spawn_core_kthreads(void) { - if (cpu_online(smp_processor_id())) - raise_softirq(RCU_SOFTIRQ); + int cpu; + + for_each_possible_cpu(cpu) + per_cpu(rcu_cpu_has_work, cpu) = 0; + BUG_ON(smpboot_register_percpu_thread(&rcu_cpu_thread_spec)); + return 0; } +early_initcall(rcu_spawn_core_kthreads); /* * Handle any core-RCU processing required by a call_rcu() invocation. @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2479 @ void call_rcu_sched(struct rcu_head *hea } EXPORT_SYMBOL_GPL(call_rcu_sched); +#ifndef CONFIG_PREEMPT_RT_FULL /* * Queue an RCU callback for invocation after a quicker grace period. */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2488 @ void call_rcu_bh(struct rcu_head *head, __call_rcu(head, func, &rcu_bh_state, -1, 0); } EXPORT_SYMBOL_GPL(call_rcu_bh); +#endif /* * Because a context switch is a grace period for RCU-sched and RCU-bh, @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2566 @ void synchronize_sched(void) } EXPORT_SYMBOL_GPL(synchronize_sched); +#ifndef CONFIG_PREEMPT_RT_FULL /** * synchronize_rcu_bh - wait until an rcu_bh grace period has elapsed. * @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2593 @ void synchronize_rcu_bh(void) wait_rcu_gp(call_rcu_bh); } EXPORT_SYMBOL_GPL(synchronize_rcu_bh); +#endif static int synchronize_sched_expedited_cpu_stop(void *data) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2768 @ static int __rcu_pending(struct rcu_stat /* Check for CPU stalls, if enabled. */ check_cpu_stall(rsp, rdp); + /* Is this CPU a NO_HZ_FULL CPU that should ignore RCU? */ + if (rcu_nohz_full_cpu(rsp)) + return 0; + /* Is the RCU core waiting for a quiescent state from this CPU? */ if (rcu_scheduler_fully_active && rdp->qs_pending && !rdp->passed_quiesce) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:3005 @ static void _rcu_barrier(struct rcu_stat mutex_unlock(&rsp->barrier_mutex); } +#ifndef CONFIG_PREEMPT_RT_FULL /** * rcu_barrier_bh - Wait until all in-flight call_rcu_bh() callbacks complete. */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:3014 @ void rcu_barrier_bh(void) _rcu_barrier(&rcu_bh_state); } EXPORT_SYMBOL_GPL(rcu_barrier_bh); +#endif /** * rcu_barrier_sched - Wait for in-flight call_rcu_sched() callbacks. @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:3318 @ static void __init rcu_init_one(struct r } rsp->rda = rda; - init_waitqueue_head(&rsp->gp_wq); + init_swait_head(&rsp->gp_wq); init_irq_work(&rsp->wakeup_work, rsp_wakeup); rnp = rsp->level[rcu_num_lvls - 1]; for_each_possible_cpu(i) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:3414 @ void __init rcu_init(void) rcu_init_one(&rcu_sched_state, &rcu_sched_data); rcu_init_one(&rcu_bh_state, &rcu_bh_data); __rcu_init_preempt(); - open_softirq(RCU_SOFTIRQ, rcu_process_callbacks); /* * We don't need protection against CPU-hotplug here because Index: linux-3.12.19-rt30/kernel/rcutree.h =================================================================== --- linux-3.12.19-rt30.orig/kernel/rcutree.h +++ linux-3.12.19-rt30/kernel/rcutree.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:31 @ #include <linux/cpumask.h> #include <linux/seqlock.h> #include <linux/irq_work.h> +#include <linux/wait-simple.h> /* * Define shape of hierarchy based on NR_CPUS, CONFIG_RCU_FANOUT, and @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:204 @ struct rcu_node { /* This can happen due to race conditions. */ #endif /* #ifdef CONFIG_RCU_BOOST */ #ifdef CONFIG_RCU_NOCB_CPU - wait_queue_head_t nocb_gp_wq[2]; + struct swait_head nocb_gp_wq[2]; /* Place for rcu_nocb_kthread() to wait GP. */ #endif /* #ifdef CONFIG_RCU_NOCB_CPU */ int need_future_gp[2]; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:337 @ struct rcu_data { atomic_long_t nocb_q_count_lazy; /* (approximate). */ int nocb_p_count; /* # CBs being invoked by kthread */ int nocb_p_count_lazy; /* (approximate). */ - wait_queue_head_t nocb_wq; /* For nocb kthreads to sleep on. */ + struct swait_head nocb_wq; /* For nocb kthreads to sleep on. */ struct task_struct *nocb_kthread; #endif /* #ifdef CONFIG_RCU_NOCB_CPU */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:407 @ struct rcu_state { unsigned long gpnum; /* Current gp number. */ unsigned long completed; /* # of last completed gp. */ struct task_struct *gp_kthread; /* Task for grace periods. */ - wait_queue_head_t gp_wq; /* Where GP task waits. */ + struct swait_head gp_wq; /* Where GP task waits. */ int gp_flags; /* Commands for GP task. */ /* End of fields guarded by root rcu_node's lock. */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:531 @ static void rcu_report_exp_rnp(struct rc static void __init __rcu_init_preempt(void); static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags); static void rcu_preempt_boost_start_gp(struct rcu_node *rnp); -static void invoke_rcu_callbacks_kthread(void); static bool rcu_is_callbacks_kthread(void); +static void rcu_cpu_kthread_setup(unsigned int cpu); #ifdef CONFIG_RCU_BOOST -static void rcu_preempt_do_callbacks(void); static int rcu_spawn_one_boost_kthread(struct rcu_state *rsp, struct rcu_node *rnp); #endif /* #ifdef CONFIG_RCU_BOOST */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:567 @ static void rcu_sysidle_report_gp(struct unsigned long maxj); static void rcu_bind_gp_kthread(void); static void rcu_sysidle_init_percpu_data(struct rcu_dynticks *rdtp); +static bool rcu_nohz_full_cpu(struct rcu_state *rsp); #endif /* #ifndef RCU_TREE_NONCORE */ Index: linux-3.12.19-rt30/kernel/rcutree_plugin.h =================================================================== --- linux-3.12.19-rt30.orig/kernel/rcutree_plugin.h +++ linux-3.12.19-rt30/kernel/rcutree_plugin.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:27 @ * Paul E. McKenney <paulmck@linux.vnet.ibm.com> */ -#include <linux/delay.h> -#include <linux/gfp.h> -#include <linux/oom.h> -#include <linux/smpboot.h> -#include "time/tick-internal.h" - #define RCU_KTHREAD_PRIO 1 #ifdef CONFIG_RCU_BOOST @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:356 @ void rcu_read_unlock_special(struct task } /* Hardware IRQ handlers cannot block. */ - if (in_irq() || in_serving_softirq()) { + if (preempt_count() & (HARDIRQ_MASK | SOFTIRQ_OFFSET)) { local_irq_restore(flags); return; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:653 @ static void rcu_preempt_check_callbacks( t->rcu_read_unlock_special |= RCU_READ_UNLOCK_NEED_QS; } -#ifdef CONFIG_RCU_BOOST - -static void rcu_preempt_do_callbacks(void) -{ - rcu_do_batch(&rcu_preempt_state, &__get_cpu_var(rcu_preempt_data)); -} - -#endif /* #ifdef CONFIG_RCU_BOOST */ - /* * Queue a preemptible-RCU callback for invocation after a grace period. */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1114 @ void exit_rcu(void) #endif /* #else #ifdef CONFIG_TREE_PREEMPT_RCU */ +/* + * If boosting, set rcuc kthreads to realtime priority. + */ +static void rcu_cpu_kthread_setup(unsigned int cpu) +{ +#ifdef CONFIG_RCU_BOOST + struct sched_param sp; + + sp.sched_priority = RCU_KTHREAD_PRIO; + sched_setscheduler_nocheck(current, SCHED_FIFO, &sp); +#endif /* #ifdef CONFIG_RCU_BOOST */ +} + #ifdef CONFIG_RCU_BOOST #include "rtmutex_common.h" @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1158 @ static void rcu_initiate_boost_trace(str #endif /* #else #ifdef CONFIG_RCU_TRACE */ -static void rcu_wake_cond(struct task_struct *t, int status) -{ - /* - * If the thread is yielding, only wake it when this - * is invoked from idle - */ - if (status != RCU_KTHREAD_YIELDING || is_idle_task(current)) - wake_up_process(t); -} - /* * Carry out RCU priority boosting on the task indicated by ->exp_tasks * or ->boost_tasks, advancing the pointer to the next task in the @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1301 @ static void rcu_initiate_boost(struct rc } /* - * Wake up the per-CPU kthread to invoke RCU callbacks. - */ -static void invoke_rcu_callbacks_kthread(void) -{ - unsigned long flags; - - local_irq_save(flags); - __this_cpu_write(rcu_cpu_has_work, 1); - if (__this_cpu_read(rcu_cpu_kthread_task) != NULL && - current != __this_cpu_read(rcu_cpu_kthread_task)) { - rcu_wake_cond(__this_cpu_read(rcu_cpu_kthread_task), - __this_cpu_read(rcu_cpu_kthread_status)); - } - local_irq_restore(flags); -} - -/* * Is the current CPU running the RCU-callbacks kthread? * Caller must have preemption disabled. */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1354 @ static int rcu_spawn_one_boost_kthread(s return 0; } -static void rcu_kthread_do_work(void) -{ - rcu_do_batch(&rcu_sched_state, &__get_cpu_var(rcu_sched_data)); - rcu_do_batch(&rcu_bh_state, &__get_cpu_var(rcu_bh_data)); - rcu_preempt_do_callbacks(); -} - -static void rcu_cpu_kthread_setup(unsigned int cpu) -{ - struct sched_param sp; - - sp.sched_priority = RCU_KTHREAD_PRIO; - sched_setscheduler_nocheck(current, SCHED_FIFO, &sp); -} - -static void rcu_cpu_kthread_park(unsigned int cpu) -{ - per_cpu(rcu_cpu_kthread_status, cpu) = RCU_KTHREAD_OFFCPU; -} - -static int rcu_cpu_kthread_should_run(unsigned int cpu) -{ - return __get_cpu_var(rcu_cpu_has_work); -} - -/* - * Per-CPU kernel thread that invokes RCU callbacks. This replaces the - * RCU softirq used in flavors and configurations of RCU that do not - * support RCU priority boosting. - */ -static void rcu_cpu_kthread(unsigned int cpu) -{ - unsigned int *statusp = &__get_cpu_var(rcu_cpu_kthread_status); - char work, *workp = &__get_cpu_var(rcu_cpu_has_work); - int spincnt; - - for (spincnt = 0; spincnt < 10; spincnt++) { - trace_rcu_utilization(TPS("Start CPU kthread@rcu_wait")); - local_bh_disable(); - *statusp = RCU_KTHREAD_RUNNING; - this_cpu_inc(rcu_cpu_kthread_loops); - local_irq_disable(); - work = *workp; - *workp = 0; - local_irq_enable(); - if (work) - rcu_kthread_do_work(); - local_bh_enable(); - if (*workp == 0) { - trace_rcu_utilization(TPS("End CPU kthread@rcu_wait")); - *statusp = RCU_KTHREAD_WAITING; - return; - } - } - *statusp = RCU_KTHREAD_YIELDING; - trace_rcu_utilization(TPS("Start CPU kthread@rcu_yield")); - schedule_timeout_interruptible(2); - trace_rcu_utilization(TPS("End CPU kthread@rcu_yield")); - *statusp = RCU_KTHREAD_WAITING; -} - /* * Set the per-rcu_node kthread's affinity to cover all CPUs that are * served by the rcu_node in question. The CPU hotplug lock is still @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1387 @ static void rcu_boost_kthread_setaffinit free_cpumask_var(cm); } -static struct smp_hotplug_thread rcu_cpu_thread_spec = { - .store = &rcu_cpu_kthread_task, - .thread_should_run = rcu_cpu_kthread_should_run, - .thread_fn = rcu_cpu_kthread, - .thread_comm = "rcuc/%u", - .setup = rcu_cpu_kthread_setup, - .park = rcu_cpu_kthread_park, -}; - /* * Spawn all kthreads -- called as soon as the scheduler is running. */ static int __init rcu_spawn_kthreads(void) { struct rcu_node *rnp; - int cpu; rcu_scheduler_fully_active = 1; - for_each_possible_cpu(cpu) - per_cpu(rcu_cpu_has_work, cpu) = 0; - BUG_ON(smpboot_register_percpu_thread(&rcu_cpu_thread_spec)); rnp = rcu_get_root(rcu_state); (void)rcu_spawn_one_boost_kthread(rcu_state, rnp); if (NUM_RCU_NODES > 1) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1422 @ static void rcu_initiate_boost(struct rc raw_spin_unlock_irqrestore(&rnp->lock, flags); } -static void invoke_rcu_callbacks_kthread(void) -{ - WARN_ON_ONCE(1); -} - static bool rcu_is_callbacks_kthread(void) { return false; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1448 @ static void rcu_prepare_kthreads(int cpu #endif /* #else #ifdef CONFIG_RCU_BOOST */ -#if !defined(CONFIG_RCU_FAST_NO_HZ) +#if !defined(CONFIG_RCU_FAST_NO_HZ) || defined(CONFIG_PREEMPT_RT_FULL) /* * Check to see if any future RCU-related work will need to be done @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1464 @ int rcu_needs_cpu(int cpu, unsigned long *delta_jiffies = ULONG_MAX; return rcu_cpu_has_callbacks(cpu, NULL); } +#endif /* !defined(CONFIG_RCU_FAST_NO_HZ) || defined(CONFIG_PREEMPT_RT_FULL) */ + +#if !defined(CONFIG_RCU_FAST_NO_HZ) /* * Because we do not have RCU_FAST_NO_HZ, don't bother cleaning up @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1564 @ static bool rcu_try_advance_all_cbs(void return cbs_ready; } +#ifndef CONFIG_PREEMPT_RT_FULL + /* * Allow the CPU to enter dyntick-idle mode unless it has callbacks ready * to invoke. If the CPU has callbacks, try to advance them. Tell the @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1604 @ int rcu_needs_cpu(int cpu, unsigned long } return 0; } +#endif /* #ifndef CONFIG_PREEMPT_RT_FULL */ /* * Prepare a CPU for idle from an RCU perspective. The first major task @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1962 @ static int rcu_nocb_needs_gp(struct rcu_ */ static void rcu_nocb_gp_cleanup(struct rcu_state *rsp, struct rcu_node *rnp) { - wake_up_all(&rnp->nocb_gp_wq[rnp->completed & 0x1]); + swait_wake_all(&rnp->nocb_gp_wq[rnp->completed & 0x1]); } /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1980 @ static void rcu_nocb_gp_set(struct rcu_n static void rcu_init_one_nocb(struct rcu_node *rnp) { - init_waitqueue_head(&rnp->nocb_gp_wq[0]); - init_waitqueue_head(&rnp->nocb_gp_wq[1]); + init_swait_head(&rnp->nocb_gp_wq[0]); + init_swait_head(&rnp->nocb_gp_wq[1]); } /* Is the specified CPU a no-CPUs CPU? */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2021 @ static void __call_rcu_nocb_enqueue(stru return; len = atomic_long_read(&rdp->nocb_q_count); if (old_rhpp == &rdp->nocb_head) { - wake_up(&rdp->nocb_wq); /* ... only if queue was empty ... */ + swait_wake(&rdp->nocb_wq); /* ... only if queue was empty ... */ rdp->qlen_last_fqs_check = 0; } else if (len > rdp->qlen_last_fqs_check + qhimark) { wake_up_process(t); /* ... or if many callbacks queued. */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2111 @ static void rcu_nocb_wait_gp(struct rcu_ */ trace_rcu_future_gp(rnp, rdp, c, TPS("StartWait")); for (;;) { - wait_event_interruptible( + swait_event_interruptible( rnp->nocb_gp_wq[c & 0x1], (d = ULONG_CMP_GE(ACCESS_ONCE(rnp->completed), c))); if (likely(d)) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2139 @ static int rcu_nocb_kthread(void *arg) for (;;) { /* If not polling, wait for next batch of callbacks. */ if (!rcu_nocb_poll) - wait_event_interruptible(rdp->nocb_wq, rdp->nocb_head); + swait_event_interruptible(rdp->nocb_wq, rdp->nocb_head); list = ACCESS_ONCE(rdp->nocb_head); if (!list) { schedule_timeout_interruptible(1); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2189 @ static int rcu_nocb_kthread(void *arg) static void __init rcu_boot_init_nocb_percpu_data(struct rcu_data *rdp) { rdp->nocb_tail = &rdp->nocb_head; - init_waitqueue_head(&rdp->nocb_wq); + init_swait_head(&rdp->nocb_wq); } /* Create a kthread for each RCU flavor for each no-CBs CPU. */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2704 @ static void rcu_sysidle_init_percpu_data } #endif /* #else #ifdef CONFIG_NO_HZ_FULL_SYSIDLE */ + +/* + * Is this CPU a NO_HZ_FULL CPU that should ignore RCU so that the + * grace-period kthread will do force_quiescent_state() processing? + * The idea is to avoid waking up RCU core processing on such a + * CPU unless the grace period has extended for too long. + * + * This code relies on the fact that all NO_HZ_FULL CPUs are also + * CONFIG_RCU_NOCB_CPUs. + */ +static bool rcu_nohz_full_cpu(struct rcu_state *rsp) +{ +#ifdef CONFIG_NO_HZ_FULL + if (tick_nohz_full_cpu(smp_processor_id()) && + (!rcu_gp_in_progress(rsp) || + ULONG_CMP_LT(jiffies, ACCESS_ONCE(rsp->gp_start) + HZ))) + return 1; +#endif /* #ifdef CONFIG_NO_HZ_FULL */ + return 0; +} Index: linux-3.12.19-rt30/kernel/relay.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/relay.c +++ linux-3.12.19-rt30/kernel/relay.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:342 @ static void wakeup_readers(unsigned long { struct rchan_buf *buf = (struct rchan_buf *)data; wake_up_interruptible(&buf->read_wait); + /* + * Stupid polling for now: + */ + mod_timer(&buf->timer, jiffies + 1); } /** @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:363 @ static void __relay_reset(struct rchan_b init_waitqueue_head(&buf->read_wait); kref_init(&buf->kref); setup_timer(&buf->timer, wakeup_readers, (unsigned long)buf); + mod_timer(&buf->timer, jiffies + 1); } else del_timer_sync(&buf->timer); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:747 @ size_t relay_switch_subbuf(struct rchan_ else buf->early_bytes += buf->chan->subbuf_size - buf->padding[old_subbuf]; - smp_mb(); - if (waitqueue_active(&buf->read_wait)) - /* - * Calling wake_up_interruptible() from here - * will deadlock if we happen to be logging - * from the scheduler (trying to re-grab - * rq->lock), so defer it. - */ - mod_timer(&buf->timer, jiffies + 1); } old = buf->data; Index: linux-3.12.19-rt30/kernel/res_counter.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/res_counter.c +++ linux-3.12.19-rt30/kernel/res_counter.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:52 @ static int __res_counter_charge(struct r r = ret = 0; *limit_fail_at = NULL; - local_irq_save(flags); + local_irq_save_nort(flags); for (c = counter; c != NULL; c = c->parent) { spin_lock(&c->lock); r = res_counter_charge_locked(c, val, force); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:72 @ static int __res_counter_charge(struct r spin_unlock(&u->lock); } } - local_irq_restore(flags); + local_irq_restore_nort(flags); return ret; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:106 @ u64 res_counter_uncharge_until(struct re struct res_counter *c; u64 ret = 0; - local_irq_save(flags); + local_irq_save_nort(flags); for (c = counter; c != top; c = c->parent) { u64 r; spin_lock(&c->lock); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:115 @ u64 res_counter_uncharge_until(struct re ret = r; spin_unlock(&c->lock); } - local_irq_restore(flags); + local_irq_restore_nort(flags); return ret; } Index: linux-3.12.19-rt30/kernel/rt.c =================================================================== --- /dev/null +++ linux-3.12.19-rt30/kernel/rt.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:4 @ +/* + * kernel/rt.c + * + * 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 "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); + +void __lockfunc _mutex_lock(struct mutex *lock) +{ + mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_); + rt_mutex_lock(&lock->lock); +} +EXPORT_SYMBOL(_mutex_lock); + +int __lockfunc _mutex_lock_interruptible(struct mutex *lock) +{ + int ret; + + mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_); + ret = rt_mutex_lock_interruptible(&lock->lock, 0); + if (ret) + mutex_release(&lock->dep_map, 1, _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 = rt_mutex_lock_killable(&lock->lock, 0); + if (ret) + mutex_release(&lock->dep_map, 1, _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_); + rt_mutex_lock(&lock->lock); +} +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_); + rt_mutex_lock(&lock->lock); +} +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 = rt_mutex_lock_interruptible(&lock->lock, 0); + if (ret) + mutex_release(&lock->dep_map, 1, _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 = rt_mutex_lock_killable(&lock->lock, 0); + if (ret) + mutex_release(&lock->dep_map, 1, _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, 1, _RET_IP_); + rt_mutex_unlock(&lock->lock); +} +EXPORT_SYMBOL(_mutex_unlock); + +/* + * rwlock_t functions + */ +int __lockfunc rt_write_trylock(rwlock_t *rwlock) +{ + int ret; + + migrate_disable(); + ret = rt_mutex_trylock(&rwlock->lock); + + if (ret) + rwlock_acquire(&rwlock->dep_map, 0, 1, _RET_IP_); + else + migrate_enable(); + + return ret; +} +EXPORT_SYMBOL(rt_write_trylock); + +int __lockfunc rt_write_trylock_irqsave(rwlock_t *rwlock, unsigned long *flags) +{ + int ret; + + *flags = 0; + ret = rt_write_trylock(rwlock); + return ret; +} +EXPORT_SYMBOL(rt_write_trylock_irqsave); + +int __lockfunc rt_read_trylock(rwlock_t *rwlock) +{ + struct rt_mutex *lock = &rwlock->lock; + int ret = 1; + + /* + * recursive read locks succeed when current owns the lock, + * but not when read_depth == 0 which means that the lock is + * write locked. + */ + if (rt_mutex_owner(lock) != current) { + migrate_disable(); + ret = rt_mutex_trylock(lock); + if (ret) + rwlock_acquire(&rwlock->dep_map, 0, 1, _RET_IP_); + else + migrate_enable(); + } else if (!rwlock->read_depth) { + ret = 0; + } + + if (ret) + rwlock->read_depth++; + + return ret; +} +EXPORT_SYMBOL(rt_read_trylock); + +void __lockfunc rt_write_lock(rwlock_t *rwlock) +{ + rwlock_acquire(&rwlock->dep_map, 0, 0, _RET_IP_); + migrate_disable(); + __rt_spin_lock(&rwlock->lock); +} +EXPORT_SYMBOL(rt_write_lock); + +void __lockfunc rt_read_lock(rwlock_t *rwlock) +{ + struct rt_mutex *lock = &rwlock->lock; + + /* + * recursive read locks succeed when current owns the lock + */ + if (rt_mutex_owner(lock) != current) { + rwlock_acquire(&rwlock->dep_map, 0, 0, _RET_IP_); + migrate_disable(); + __rt_spin_lock(lock); + } + rwlock->read_depth++; +} + +EXPORT_SYMBOL(rt_read_lock); + +void __lockfunc rt_write_unlock(rwlock_t *rwlock) +{ + /* NOTE: we always pass in '1' for nested, for simplicity */ + rwlock_release(&rwlock->dep_map, 1, _RET_IP_); + __rt_spin_unlock(&rwlock->lock); + migrate_enable(); +} +EXPORT_SYMBOL(rt_write_unlock); + +void __lockfunc rt_read_unlock(rwlock_t *rwlock) +{ + /* Release the lock only when read_depth is down to 0 */ + if (--rwlock->read_depth == 0) { + rwlock_release(&rwlock->dep_map, 1, _RET_IP_); + __rt_spin_unlock(&rwlock->lock); + migrate_enable(); + } +} +EXPORT_SYMBOL(rt_read_unlock); + +unsigned long __lockfunc rt_write_lock_irqsave(rwlock_t *rwlock) +{ + rt_write_lock(rwlock); + + return 0; +} +EXPORT_SYMBOL(rt_write_lock_irqsave); + +unsigned long __lockfunc rt_read_lock_irqsave(rwlock_t *rwlock) +{ + rt_read_lock(rwlock); + + return 0; +} +EXPORT_SYMBOL(rt_read_lock_irqsave); + +void __rt_rwlock_init(rwlock_t *rwlock, 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 *)rwlock, sizeof(*rwlock)); + lockdep_init_map(&rwlock->dep_map, name, key, 0); +#endif + rwlock->lock.save_state = 1; + rwlock->read_depth = 0; +} +EXPORT_SYMBOL(__rt_rwlock_init); + +/* + * rw_semaphores + */ + +void rt_up_write(struct rw_semaphore *rwsem) +{ + rwsem_release(&rwsem->dep_map, 1, _RET_IP_); + rt_mutex_unlock(&rwsem->lock); +} +EXPORT_SYMBOL(rt_up_write); + +void rt_up_read(struct rw_semaphore *rwsem) +{ + if (--rwsem->read_depth == 0) { + rwsem_release(&rwsem->dep_map, 1, _RET_IP_); + rt_mutex_unlock(&rwsem->lock); + } +} +EXPORT_SYMBOL(rt_up_read); + +/* + * downgrade a write lock into a read lock + * - just wake up any readers at the front of the queue + */ +void rt_downgrade_write(struct rw_semaphore *rwsem) +{ + BUG_ON(rt_mutex_owner(&rwsem->lock) != current); + rwsem->read_depth = 1; +} +EXPORT_SYMBOL(rt_downgrade_write); + +int rt_down_write_trylock(struct rw_semaphore *rwsem) +{ + int ret = rt_mutex_trylock(&rwsem->lock); + + if (ret) + rwsem_acquire(&rwsem->dep_map, 0, 1, _RET_IP_); + return ret; +} +EXPORT_SYMBOL(rt_down_write_trylock); + +void rt_down_write(struct rw_semaphore *rwsem) +{ + rwsem_acquire(&rwsem->dep_map, 0, 0, _RET_IP_); + rt_mutex_lock(&rwsem->lock); +} +EXPORT_SYMBOL(rt_down_write); + +void rt_down_write_nested(struct rw_semaphore *rwsem, int subclass) +{ + rwsem_acquire(&rwsem->dep_map, subclass, 0, _RET_IP_); + rt_mutex_lock(&rwsem->lock); +} +EXPORT_SYMBOL(rt_down_write_nested); + +void rt_down_write_nested_lock(struct rw_semaphore *rwsem, + struct lockdep_map *nest) +{ + rwsem_acquire_nest(&rwsem->dep_map, 0, 0, nest, _RET_IP_); + rt_mutex_lock(&rwsem->lock); +} + +int rt_down_read_trylock(struct rw_semaphore *rwsem) +{ + struct rt_mutex *lock = &rwsem->lock; + int ret = 1; + + /* + * recursive read locks succeed when current owns the rwsem, + * but not when read_depth == 0 which means that the rwsem is + * write locked. + */ + if (rt_mutex_owner(lock) != current) { + ret = rt_mutex_trylock(&rwsem->lock); + if (ret) + rwsem_acquire(&rwsem->dep_map, 0, 1, _RET_IP_); + } else if (!rwsem->read_depth) { + ret = 0; + } + + if (ret) + rwsem->read_depth++; + return ret; +} +EXPORT_SYMBOL(rt_down_read_trylock); + +static void __rt_down_read(struct rw_semaphore *rwsem, int subclass) +{ + struct rt_mutex *lock = &rwsem->lock; + + if (rt_mutex_owner(lock) != current) { + rwsem_acquire(&rwsem->dep_map, subclass, 0, _RET_IP_); + rt_mutex_lock(&rwsem->lock); + } + rwsem->read_depth++; +} + +void rt_down_read(struct rw_semaphore *rwsem) +{ + __rt_down_read(rwsem, 0); +} +EXPORT_SYMBOL(rt_down_read); + +void rt_down_read_nested(struct rw_semaphore *rwsem, int subclass) +{ + __rt_down_read(rwsem, subclass); +} +EXPORT_SYMBOL(rt_down_read_nested); + +void __rt_rwsem_init(struct rw_semaphore *rwsem, 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 *)rwsem, sizeof(*rwsem)); + lockdep_init_map(&rwsem->dep_map, name, key, 0); +#endif + rwsem->read_depth = 0; + rwsem->lock.save_state = 0; +} +EXPORT_SYMBOL(__rt_rwsem_init); + +/** + * 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); Index: linux-3.12.19-rt30/kernel/rtmutex.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/rtmutex.c +++ linux-3.12.19-rt30/kernel/rtmutex.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:11 @ * 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/rt-mutex-design.txt for details. */ #include <linux/spinlock.h> @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:24 @ #include <linux/sched.h> #include <linux/sched/rt.h> #include <linux/timer.h> +#include <linux/ww_mutex.h> #include "rtmutex_common.h" @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:78 @ static void fixup_rt_mutex_waiters(struc clear_rt_mutex_waiters(lock); } +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 the architecture * supports cmpxchg and if there's no debugging state to be set up @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:159 @ static inline bool unlock_rt_mutex_safe( } #endif +static inline void init_lists(struct rt_mutex *lock) +{ + if (unlikely(!lock->wait_list.node_list.prev)) + plist_head_init(&lock->wait_list); +} + /* * Calculate task priority from the waiter list priority * @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:181 @ int rt_mutex_getprio(struct task_struct } /* + * Called by sched_setscheduler() to check whether the priority change + * is overruled by a possible priority boosting. + */ +int rt_mutex_check_prio(struct task_struct *task, int newprio) +{ + if (!task_has_pi_waiters(task)) + return 0; + + return task_top_pi_waiter(task)->pi_list_entry.prio <= newprio; +} + +/* * Adjust the priority of a task, after its pi_waiters got modified. * * This can be both boosting and unboosting. task->pi_lock must be held. @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:223 @ static void rt_mutex_adjust_prio(struct raw_spin_unlock_irqrestore(&task->pi_lock, flags); } +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: */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:238 @ 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; + struct rt_mutex_waiter *waiter = p->pi_blocked_on; + return rt_mutex_real_waiter(waiter) ? waiter->lock : NULL; } /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:314 @ static int rt_mutex_adjust_prio_chain(st * 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; /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:389 @ static int rt_mutex_adjust_prio_chain(st /* Release the task */ raw_spin_unlock_irqrestore(&task->pi_lock, flags); if (!rt_mutex_owner(lock)) { + struct rt_mutex_waiter *lock_top_waiter; + /* * If the requeue above changed the top waiter, then we need * to wake the new top waiter up to try to get the lock. */ - - if (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 (top_waiter != lock_top_waiter) + rt_mutex_wake_waiter(lock_top_waiter); raw_spin_unlock(&lock->wait_lock); goto out_put_task; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:457 @ static int rt_mutex_adjust_prio_chain(st return ret; } + +#define STEAL_NORMAL 0 +#define STEAL_LATERAL 1 + +/* + * Note that RT tasks are excluded from lateral-steals to prevent the + * introduction of an unbounded latency + */ +static inline int lock_is_stealable(struct task_struct *task, + struct task_struct *pendowner, int mode) +{ + if (mode == STEAL_NORMAL || rt_task(task)) { + if (task->prio >= pendowner->prio) + return 0; + } else if (task->prio > pendowner->prio) + return 0; + return 1; +} + /* * Try to take an rt-mutex * @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:485 @ static int rt_mutex_adjust_prio_chain(st * @task: the task which wants to acquire the lock * @waiter: the waiter that is queued to the lock's wait list. (could be NULL) */ -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) { /* * We have to be careful here if the atomic speedups are @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:520 @ static int try_to_take_rt_mutex(struct r * 3) it is top waiter */ if (rt_mutex_has_waiters(lock)) { - if (task->prio >= rt_mutex_top_waiter(lock)->list_entry.prio) { - if (!waiter || waiter != rt_mutex_top_waiter(lock)) - return 0; - } + struct task_struct *pown = rt_mutex_top_waiter(lock)->task; + + if (task != pown && !lock_is_stealable(task, pown, mode)) + return 0; } + /* We got the lock. */ + if (waiter || rt_mutex_has_waiters(lock)) { unsigned long flags; struct rt_mutex_waiter *top; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:552 @ static int try_to_take_rt_mutex(struct r raw_spin_unlock_irqrestore(&task->pi_lock, flags); } - /* We got the lock. */ debug_rt_mutex_lock(lock); rt_mutex_set_owner(lock, task); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:561 @ static int try_to_take_rt_mutex(struct r return 1; } +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. * @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:599 @ static int task_blocks_on_rt_mutex(struc return -EDEADLK; raw_spin_lock_irqsave(&task->pi_lock, flags); + + /* + * 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_irqrestore(&task->pi_lock, flags); + return -EAGAIN; + } + + BUG_ON(rt_mutex_real_waiter(task->pi_blocked_on)); + __rt_mutex_adjust_prio(task); waiter->task = task; waiter->lock = lock; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:640 @ static int task_blocks_on_rt_mutex(struc plist_add(&waiter->pi_list_entry, &owner->pi_waiters); __rt_mutex_adjust_prio(owner); - if (owner->pi_blocked_on) + if (rt_mutex_real_waiter(owner->pi_blocked_on)) chain_walk = 1; } else if (debug_rt_mutex_detect_deadlock(waiter, detect_deadlock)) { chain_walk = 1; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:717 @ static void wakeup_next_waiter(struct rt * long as we hold lock->wait_lock. The waiter task needs to * acquire it in order to dequeue the waiter. */ - wake_up_process(waiter->task); + rt_mutex_wake_waiter(waiter); } /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:791 @ void rt_mutex_adjust_pi(struct task_stru raw_spin_lock_irqsave(&task->pi_lock, flags); waiter = task->pi_blocked_on; - if (!waiter || waiter->list_entry.prio == task->prio) { + if (!rt_mutex_real_waiter(waiter) || + waiter->list_entry.prio == task->prio) { 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, 0, NULL, next_lock, NULL, task); } +#ifdef CONFIG_PREEMPT_RT_FULL +/* + * preemptible spin_lock functions: + */ +static inline void rt_spin_lock_fastlock(struct rt_mutex *lock, + void (*slowfn)(struct rt_mutex *lock)) +{ + might_sleep(); + + if (likely(rt_mutex_cmpxchg(lock, NULL, current))) + rt_mutex_deadlock_account_lock(lock, current); + 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(lock, current, NULL))) + rt_mutex_deadlock_account_unlock(current); + 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 + +# define pi_lock(lock) raw_spin_lock_irq(lock) +# define pi_unlock(lock) raw_spin_unlock_irq(lock) + +/* + * 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. + */ +static void noinline __sched rt_spin_lock_slowlock(struct rt_mutex *lock) +{ + struct task_struct *lock_owner, *self = current; + struct rt_mutex_waiter waiter, *top_waiter; + int ret; + + rt_mutex_init_waiter(&waiter, true); + + raw_spin_lock(&lock->wait_lock); + init_lists(lock); + + if (__try_to_take_rt_mutex(lock, self, NULL, STEAL_LATERAL)) { + raw_spin_unlock(&lock->wait_lock); + 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(). + */ + pi_lock(&self->pi_lock); + self->saved_state = self->state; + __set_current_state(TASK_UNINTERRUPTIBLE); + pi_unlock(&self->pi_lock); + + ret = task_blocks_on_rt_mutex(lock, &waiter, self, 0); + 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(&lock->wait_lock); + + debug_rt_mutex_print_deadlock(&waiter); + + if (top_waiter != &waiter || adaptive_wait(lock, lock_owner)) + schedule_rt_mutex(lock); + + raw_spin_lock(&lock->wait_lock); + + pi_lock(&self->pi_lock); + __set_current_state(TASK_UNINTERRUPTIBLE); + pi_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. + */ + pi_lock(&self->pi_lock); + __set_current_state(self->saved_state); + self->saved_state = TASK_RUNNING; + pi_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(!plist_node_empty(&waiter.list_entry)); + + raw_spin_unlock(&lock->wait_lock); + + debug_rt_mutex_free_waiter(&waiter); +} + +/* + * Slow path to release a rt_mutex spin_lock style + */ +static void __sched __rt_spin_lock_slowunlock(struct rt_mutex *lock) +{ + debug_rt_mutex_unlock(lock); + + rt_mutex_deadlock_account_unlock(current); + + if (!rt_mutex_has_waiters(lock)) { + lock->owner = NULL; + raw_spin_unlock(&lock->wait_lock); + return; + } + + wakeup_next_waiter(lock); + + raw_spin_unlock(&lock->wait_lock); + + /* Undo pi boosting.when necessary */ + rt_mutex_adjust_prio(current); +} + +static void noinline __sched rt_spin_lock_slowunlock(struct rt_mutex *lock) +{ + raw_spin_lock(&lock->wait_lock); + __rt_spin_lock_slowunlock(lock); +} + +static void noinline __sched rt_spin_lock_slowunlock_hirq(struct rt_mutex *lock) +{ + int ret; + + do { + ret = raw_spin_trylock(&lock->wait_lock); + } while (!ret); + + __rt_spin_lock_slowunlock(lock); +} + +void __lockfunc rt_spin_lock(spinlock_t *lock) +{ + rt_spin_lock_fastlock(&lock->lock, rt_spin_lock_slowlock); + spin_acquire(&lock->dep_map, 0, 0, _RET_IP_); +} +EXPORT_SYMBOL(rt_spin_lock); + +void __lockfunc __rt_spin_lock(struct rt_mutex *lock) +{ + rt_spin_lock_fastlock(lock, rt_spin_lock_slowlock); +} +EXPORT_SYMBOL(__rt_spin_lock); + +#ifdef CONFIG_DEBUG_LOCK_ALLOC +void __lockfunc rt_spin_lock_nested(spinlock_t *lock, int subclass) +{ + rt_spin_lock_fastlock(&lock->lock, rt_spin_lock_slowlock); + spin_acquire(&lock->dep_map, subclass, 0, _RET_IP_); +} +EXPORT_SYMBOL(rt_spin_lock_nested); +#endif + +void __lockfunc rt_spin_unlock(spinlock_t *lock) +{ + /* NOTE: we always pass in '1' for nested, for simplicity */ + spin_release(&lock->dep_map, 1, _RET_IP_); + rt_spin_lock_fastunlock(&lock->lock, rt_spin_lock_slowunlock); +} +EXPORT_SYMBOL(rt_spin_unlock); + +void __lockfunc rt_spin_unlock_after_trylock_in_irq(spinlock_t *lock) +{ + /* NOTE: we always pass in '1' for nested, for simplicity */ + spin_release(&lock->dep_map, 1, _RET_IP_); + rt_spin_lock_fastunlock(&lock->lock, rt_spin_lock_slowunlock_hirq); +} + +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_unlock_wait(spinlock_t *lock) +{ + spin_lock(lock); + spin_unlock(lock); +} +EXPORT_SYMBOL(rt_spin_unlock_wait); + +int __lockfunc rt_spin_trylock(spinlock_t *lock) +{ + int ret = rt_mutex_trylock(&lock->lock); + + if (ret) + spin_acquire(&lock->dep_map, 0, 1, _RET_IP_); + 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) { + migrate_disable(); + spin_acquire(&lock->dep_map, 0, 1, _RET_IP_); + } else + local_bh_enable(); + return ret; +} +EXPORT_SYMBOL(rt_spin_trylock_bh); + +int __lockfunc rt_spin_trylock_irqsave(spinlock_t *lock, unsigned long *flags) +{ + int ret; + + *flags = 0; + ret = rt_mutex_trylock(&lock->lock); + if (ret) { + migrate_disable(); + spin_acquire(&lock->dep_map, 0, 1, _RET_IP_); + } + return ret; +} +EXPORT_SYMBOL(rt_spin_trylock_irqsave); + +int atomic_dec_and_spin_lock(atomic_t *atomic, spinlock_t *lock) +{ + /* Subtract 1 from counter unless that drops it to 0 (ie. it was 1) */ + if (atomic_add_unless(atomic, -1, 1)) + return 0; + migrate_disable(); + rt_spin_lock(lock); + if (atomic_dec_and_test(atomic)) + return 1; + rt_spin_unlock(lock); + migrate_enable(); + return 0; +} +EXPORT_SYMBOL(atomic_dec_and_spin_lock); + +void +__rt_spin_lock_init(spinlock_t *lock, 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_FULL */ + +#ifdef CONFIG_PREEMPT_RT_FULL +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 = ACCESS_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 + /** * __rt_mutex_slowlock() - Perform the wait-wake-try-to-take loop * @lock: the rt_mutex to take * @state: the state the task should block in (TASK_INTERRUPTIBLE - * or TASK_UNINTERRUPTIBLE) + * or TASK_UNINTERRUPTIBLE) * @timeout: the pre-initialized and started timer, or NULL for none * @waiter: the pre-initialized rt_mutex_waiter * @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1166 @ void rt_mutex_adjust_pi(struct task_stru 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; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1190 @ __rt_mutex_slowlock(struct rt_mutex *loc break; } + if (ww_ctx && ww_ctx->acquired > 0) { + ret = __mutex_lock_check_stamp(lock, ww_ctx); + if (ret) + break; + } + raw_spin_unlock(&lock->wait_lock); debug_rt_mutex_print_deadlock(waiter); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1209 @ __rt_mutex_slowlock(struct rt_mutex *loc return ret; } +static __always_inline void ww_mutex_lock_acquired(struct ww_mutex *ww, + struct ww_acquire_ctx *ww_ctx) +{ +#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); + + 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; + } + + /* + * Naughty, using a different class will lead to undefined behavior! + */ + DEBUG_LOCKS_WARN_ON(ww_ctx->ww_class != ww->ww_class); +#endif + ww_ctx->acquired++; +} + +#ifdef CONFIG_PREEMPT_RT_FULL +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; + + /* + * 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. + */ + plist_for_each_entry(waiter, &lock->wait_list, list_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 + static void rt_mutex_handle_deadlock(int res, int detect_deadlock, struct rt_mutex_waiter *w) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1311 @ static void rt_mutex_handle_deadlock(int static int __sched rt_mutex_slowlock(struct rt_mutex *lock, int state, struct hrtimer_sleeper *timeout, - int detect_deadlock) + int detect_deadlock, struct ww_acquire_ctx *ww_ctx) { struct rt_mutex_waiter waiter; int ret = 0; - debug_rt_mutex_init_waiter(&waiter); + rt_mutex_init_waiter(&waiter, false); raw_spin_lock(&lock->wait_lock); + init_lists(lock); /* Try to acquire the lock again: */ if (try_to_take_rt_mutex(lock, current, NULL)) { + if (ww_ctx) + ww_mutex_account_lock(lock, ww_ctx); raw_spin_unlock(&lock->wait_lock); return 0; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1341 @ rt_mutex_slowlock(struct rt_mutex *lock, ret = task_blocks_on_rt_mutex(lock, &waiter, current, detect_deadlock); if (likely(!ret)) - ret = __rt_mutex_slowlock(lock, state, timeout, &waiter); + ret = __rt_mutex_slowlock(lock, state, timeout, &waiter, ww_ctx); set_current_state(TASK_RUNNING); if (unlikely(ret)) { remove_waiter(lock, &waiter); rt_mutex_handle_deadlock(ret, detect_deadlock, &waiter); + + } else if (ww_ctx) { + ww_mutex_account_lock(lock, ww_ctx); } /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1378 @ rt_mutex_slowtrylock(struct rt_mutex *lo { int ret = 0; - raw_spin_lock(&lock->wait_lock); + if (!raw_spin_trylock(&lock->wait_lock)) + return ret; + init_lists(lock); if (likely(rt_mutex_owner(lock) != current)) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1468 @ rt_mutex_slowunlock(struct rt_mutex *loc */ static inline int rt_mutex_fastlock(struct rt_mutex *lock, int state, - int detect_deadlock, + int detect_deadlock, struct ww_acquire_ctx *ww_ctx, int (*slowfn)(struct rt_mutex *lock, int state, struct hrtimer_sleeper *timeout, - int detect_deadlock)) + int detect_deadlock, + struct ww_acquire_ctx *ww_ctx)) { if (!detect_deadlock && likely(rt_mutex_cmpxchg(lock, NULL, current))) { rt_mutex_deadlock_account_lock(lock, current); return 0; } else - return slowfn(lock, state, NULL, detect_deadlock); + return slowfn(lock, state, NULL, detect_deadlock, ww_ctx); } static inline int rt_mutex_timed_fastlock(struct rt_mutex *lock, int state, struct hrtimer_sleeper *timeout, int detect_deadlock, + struct ww_acquire_ctx *ww_ctx, int (*slowfn)(struct rt_mutex *lock, int state, struct hrtimer_sleeper *timeout, - int detect_deadlock)) + int detect_deadlock, + struct ww_acquire_ctx *ww_ctx)) { if (!detect_deadlock && likely(rt_mutex_cmpxchg(lock, NULL, current))) { rt_mutex_deadlock_account_lock(lock, current); return 0; } else - return slowfn(lock, state, timeout, detect_deadlock); + return slowfn(lock, state, timeout, detect_deadlock, ww_ctx); } static inline int @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1527 @ void __sched rt_mutex_lock(struct rt_mut { might_sleep(); - rt_mutex_fastlock(lock, TASK_UNINTERRUPTIBLE, 0, rt_mutex_slowlock); + rt_mutex_fastlock(lock, TASK_UNINTERRUPTIBLE, 0, NULL, rt_mutex_slowlock); } EXPORT_SYMBOL_GPL(rt_mutex_lock); /** * rt_mutex_lock_interruptible - lock a rt_mutex interruptible * - * @lock: the rt_mutex to be locked + * @lock: the rt_mutex to be locked * @detect_deadlock: deadlock detection on/off * * Returns: - * 0 on success - * -EINTR when interrupted by a signal + * 0 on success + * -EINTR when interrupted by a signal * -EDEADLK when the lock would deadlock (when deadlock detection is on) */ int __sched rt_mutex_lock_interruptible(struct rt_mutex *lock, @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1548 @ int __sched rt_mutex_lock_interruptible( might_sleep(); return rt_mutex_fastlock(lock, TASK_INTERRUPTIBLE, - detect_deadlock, rt_mutex_slowlock); + detect_deadlock, NULL, rt_mutex_slowlock); } EXPORT_SYMBOL_GPL(rt_mutex_lock_interruptible); /** + * rt_mutex_lock_killable - lock a rt_mutex killable + * + * @lock: the rt_mutex to be locked + * @detect_deadlock: deadlock detection on/off + * + * Returns: + * 0 on success + * -EINTR when interrupted by a signal + * -EDEADLK when the lock would deadlock (when deadlock detection is on) + */ +int __sched rt_mutex_lock_killable(struct rt_mutex *lock, + int detect_deadlock) +{ + might_sleep(); + + return rt_mutex_fastlock(lock, TASK_KILLABLE, + detect_deadlock, NULL, rt_mutex_slowlock); +} +EXPORT_SYMBOL_GPL(rt_mutex_lock_killable); + +/** * rt_mutex_timed_lock - lock a rt_mutex interruptible * the timeout structure is provided * by the caller * - * @lock: the rt_mutex to be locked + * @lock: the rt_mutex to be locked * @timeout: timeout structure or NULL (no timeout) * @detect_deadlock: deadlock detection on/off * * Returns: - * 0 on success - * -EINTR when interrupted by a signal + * 0 on success + * -EINTR when interrupted by a signal * -ETIMEDOUT when the timeout expired * -EDEADLK when the lock would deadlock (when deadlock detection is on) */ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1595 @ rt_mutex_timed_lock(struct rt_mutex *loc might_sleep(); return rt_mutex_timed_fastlock(lock, TASK_INTERRUPTIBLE, timeout, - detect_deadlock, rt_mutex_slowlock); + detect_deadlock, NULL, rt_mutex_slowlock); } EXPORT_SYMBOL_GPL(rt_mutex_timed_lock); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1653 @ EXPORT_SYMBOL_GPL(rt_mutex_destroy); void __rt_mutex_init(struct rt_mutex *lock, const char *name) { lock->owner = NULL; - raw_spin_lock_init(&lock->wait_lock); plist_head_init(&lock->wait_list); debug_rt_mutex_init(lock, name); } -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 @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1672 @ EXPORT_SYMBOL_GPL(__rt_mutex_init); void rt_mutex_init_proxy_locked(struct rt_mutex *lock, struct task_struct *proxy_owner) { - __rt_mutex_init(lock, NULL); + rt_mutex_init(lock); debug_rt_mutex_proxy_lock(lock, proxy_owner); rt_mutex_set_owner(lock, proxy_owner); rt_mutex_deadlock_account_lock(lock, proxy_owner); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1721 @ int rt_mutex_start_proxy_lock(struct rt_ return 1; } +#ifdef CONFIG_PREEMPT_RT_FULL + /* + * 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_irq(&task->pi_lock); + if (task->pi_blocked_on) { + raw_spin_unlock_irq(&task->pi_lock); + raw_spin_unlock(&lock->wait_lock); + return -EAGAIN; + } + task->pi_blocked_on = PI_REQUEUE_INPROGRESS; + raw_spin_unlock_irq(&task->pi_lock); +#endif + /* We enforce deadlock detection for futexes */ ret = task_blocks_on_rt_mutex(lock, waiter, task, 1); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1820 @ int rt_mutex_finish_proxy_lock(struct rt set_current_state(TASK_INTERRUPTIBLE); - ret = __rt_mutex_slowlock(lock, TASK_INTERRUPTIBLE, to, waiter); + ret = __rt_mutex_slowlock(lock, TASK_INTERRUPTIBLE, to, waiter, NULL); set_current_state(TASK_RUNNING); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1837 @ int rt_mutex_finish_proxy_lock(struct rt return ret; } + +static inline int +ww_mutex_deadlock_injection(struct ww_mutex *lock, struct ww_acquire_ctx *ctx) +{ +#ifdef CONFIG_DEBUG_WW_MUTEX_SLOWPATH + unsigned 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_FULL +int __sched +__ww_mutex_lock_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ww_ctx) +{ + int ret; + + might_sleep(); + + mutex_acquire(&lock->base.dep_map, 0, 0, _RET_IP_); + ret = rt_mutex_slowlock(&lock->base.lock, TASK_INTERRUPTIBLE, NULL, 0, ww_ctx); + if (ret) + mutex_release(&lock->base.dep_map, 1, _RET_IP_); + else if (!ret && ww_ctx->acquired > 1) + return ww_mutex_deadlock_injection(lock, ww_ctx); + + return ret; +} +EXPORT_SYMBOL_GPL(__ww_mutex_lock_interruptible); + +int __sched +__ww_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ww_ctx) +{ + int ret; + + might_sleep(); + + mutex_acquire_nest(&lock->base.dep_map, 0, 0, &ww_ctx->dep_map, + _RET_IP_); + ret = rt_mutex_slowlock(&lock->base.lock, TASK_UNINTERRUPTIBLE, NULL, 0, ww_ctx); + if (ret) + mutex_release(&lock->base.dep_map, 1, _RET_IP_); + else if (!ret && ww_ctx->acquired > 1) + return ww_mutex_deadlock_injection(lock, ww_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, 1, _RET_IP_); + rt_mutex_unlock(&lock->base.lock); +} +EXPORT_SYMBOL(ww_mutex_unlock); +#endif Index: linux-3.12.19-rt30/kernel/rtmutex_common.h =================================================================== --- linux-3.12.19-rt30.orig/kernel/rtmutex_common.h +++ linux-3.12.19-rt30/kernel/rtmutex_common.h @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:52 @ struct rt_mutex_waiter { struct plist_node pi_list_entry; struct task_struct *task; struct rt_mutex *lock; + bool savestate; #ifdef CONFIG_DEBUG_RT_MUTEXES unsigned long ip; struct pid *deadlock_task_pid; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:107 @ static inline struct task_struct *rt_mut /* * 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); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:130 @ extern int rt_mutex_finish_proxy_lock(st # include "rtmutex.h" #endif +static inline void +rt_mutex_init_waiter(struct rt_mutex_waiter *waiter, bool savestate) +{ + debug_rt_mutex_init_waiter(waiter); + waiter->task = NULL; + waiter->savestate = savestate; +} + #endif Index: linux-3.12.19-rt30/kernel/sched/core.c =================================================================== --- linux-3.12.19-rt30.orig/kernel/sched/core.c +++ linux-3.12.19-rt30/kernel/sched/core.c @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:275 @ late_initcall(sched_init_debug); * Number of tasks to iterate in a single balance run. * Limited because this is done with IRQs disabled. */ +#ifndef CONFIG_PREEMPT_RT_FULL const_debug unsigned int sysctl_sched_nr_migrate = 32; +#else +const_debug unsigned int sysctl_sched_nr_migrate = 8; +#endif /* * period over which we average the RT time consumption, measured @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:498 @ static void init_rq_hrtick(struct rq *rq hrtimer_init(&rq->hrtick_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); rq->hrtick_timer.function = hrtick; + rq->hrtick_timer.irqsafe = 1; } #else /* CONFIG_SCHED_HRTICK */ static inline void hrtick_clear(struct rq *rq) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:543 @ void resched_task(struct task_struct *p) smp_send_reschedule(cpu); } +#ifdef CONFIG_PREEMPT_LAZY +void resched_task_lazy(struct task_struct *p) +{ + int cpu; + + if (!sched_feat(PREEMPT_LAZY)) { + resched_task(p); + return; + } + + assert_raw_spin_locked(&task_rq(p)->lock); + + if (test_tsk_need_resched(p)) + return; + + if (test_tsk_need_resched_lazy(p)) + return; + + set_tsk_need_resched_lazy(p); + + cpu = task_cpu(p); + if (cpu == smp_processor_id()) + return; + + /* NEED_RESCHED_LAZY must be visible before we test polling */ + smp_mb(); + if (!tsk_is_polling(p)) + smp_send_reschedule(cpu); +} +#endif + void resched_cpu(int cpu) { struct rq *rq = cpu_rq(cpu); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:738 @ void resched_task(struct task_struct *p) assert_raw_spin_locked(&task_rq(p)->lock); set_tsk_need_resched(p); } +#ifdef CONFIG_PREEMPT_LAZY +void resched_task_lazy(struct task_struct *p) +{ + if (!sched_feat(PREEMPT_LAZY)) { + resched_task(p); + return; + } + assert_raw_spin_locked(&task_rq(p)->lock); + set_tsk_need_resched_lazy(p); +} +#endif #endif /* CONFIG_SMP */ #if defined(CONFIG_RT_GROUP_SCHED) || (defined(CONFIG_FAIR_GROUP_SCHED) && \ @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1074 @ struct migration_arg { static int migration_cpu_stop(void *data); +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. * @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1130 @ unsigned long wait_task_inactive(struct * 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(); } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1145 @ unsigned long wait_task_inactive(struct running = task_running(rq, p); on_rq = p->on_rq; 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, &flags); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1371 @ static void ttwu_activate(struct rq *rq, { activate_task(rq, p, en_flags); p->on_rq = 1; - - /* if a worker is waking up, notify workqueue */ - if (p->flags & PF_WQ_WORKER) - wq_worker_waking_up(p, cpu_of(rq)); } /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1545 @ try_to_wake_up(struct task_struct *p, un */ smp_mb__before_spinlock(); raw_spin_lock_irqsave(&p->pi_lock, flags); - 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 out; + } + + /* + * 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; success = 1; /* we're going to change ->state */ cpu = task_cpu(p); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1608 @ out: } /** - * try_to_wake_up_local - try to wake up a local task with rq lock held - * @p: the thread to be awakened - * - * Put @p on the run-queue if it's not already there. The caller must - * ensure that this_rq() is locked, @p is bound to this_rq() and not - * the current task. - */ -static void try_to_wake_up_local(struct task_struct *p) -{ - struct rq *rq = task_rq(p); - - if (WARN_ON_ONCE(rq != this_rq()) || - WARN_ON_ONCE(p == current)) - return; - - lockdep_assert_held(&rq->lock); - - if (!raw_spin_trylock(&p->pi_lock)) { - raw_spin_unlock(&rq->lock); - raw_spin_lock(&p->pi_lock); - raw_spin_lock(&rq->lock); - } - - if (!(p->state & TASK_NORMAL)) - goto out; - - if (!p->on_rq) - ttwu_activate(rq, p, ENQUEUE_WAKEUP); - - ttwu_do_wakeup(rq, p, 0); - ttwu_stat(p, smp_processor_id(), 0); -out: - raw_spin_unlock(&p->pi_lock); -} - -/** * wake_up_process - Wake up a specific process * @p: The process to be woken up. * @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1621 @ out: */ int wake_up_process(struct task_struct *p) { - WARN_ON(task_is_stopped_or_traced(p)); + WARN_ON(__task_is_stopped_or_traced(p)); return try_to_wake_up(p, TASK_NORMAL, 0); } 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_ALL, WF_LOCK_SLEEPER); +} + int wake_up_state(struct task_struct *p, unsigned int state) { return try_to_wake_up(p, state, 0); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1775 @ void sched_fork(struct task_struct *p) /* Want to start with kernel preemption disabled. */ task_thread_info(p)->preempt_count = 1; #endif +#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); #endif @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:1944 @ static void finish_task_switch(struct rq finish_arch_post_lock_switch(); fire_sched_in_preempt_notifiers(current); + /* + * We use mmdrop_delayed() here so we don't have to do the + * full __mmdrop() when we are the last user. + */ if (mm) - mmdrop(mm); + mmdrop_delayed(mm); if (unlikely(prev_state == TASK_DEAD)) { /* * Remove function-return probe instances associated with this @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2293 @ void __kprobes add_preempt_count(int val DEBUG_LOCKS_WARN_ON((preempt_count() & PREEMPT_MASK) >= PREEMPT_MASK - 10); #endif - if (preempt_count() == val) - trace_preempt_off(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1)); + if (preempt_count() == val) { + unsigned long ip = get_parent_ip(CALLER_ADDR1); +#ifdef CONFIG_DEBUG_PREEMPT + current->preempt_disable_ip = ip; +#endif + trace_preempt_off(CALLER_ADDR0, ip); + } } EXPORT_SYMBOL(add_preempt_count); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2342 @ static noinline void __schedule_bug(stru print_modules(); if (irqs_disabled()) print_irqtrace_events(prev); +#ifdef CONFIG_DEBUG_PREEMPT + if (in_atomic_preempt_off()) { + pr_err("Preemption disabled at:"); + print_ip_sym(current->preempt_disable_ip); + pr_cont("\n"); + } +#endif dump_stack(); add_taint(TAINT_WARN, LOCKDEP_STILL_OK); } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2372 @ static inline void schedule_debug(struct schedstat_inc(this_rq(), sched_count); } +#if defined(CONFIG_PREEMPT_RT_FULL) && defined(CONFIG_SMP) +#define MIGRATE_DISABLE_SET_AFFIN (1<<30) /* Can't make a negative */ +#define migrate_disabled_updated(p) ((p)->migrate_disable & MIGRATE_DISABLE_SET_AFFIN) +#define migrate_disable_count(p) ((p)->migrate_disable & ~MIGRATE_DISABLE_SET_AFFIN) + +static inline void update_migrate_disable(struct task_struct *p) +{ + const struct cpumask *mask; + + if (likely(!p->migrate_disable)) + return; + + /* Did we already update affinity? */ + if (unlikely(migrate_disabled_updated(p))) + return; + + /* + * Since this is always current we can get away with only locking + * rq->lock, the ->cpus_allowed value can normally only be changed + * while holding both p->pi_lock and rq->lock, but seeing that this + * is current, we cannot actually be waking up, so all code that + * relies on serialization against p->pi_lock is out of scope. + * + * Having rq->lock serializes us against things like + * set_cpus_allowed_ptr() that can still happen concurrently. + */ + mask = tsk_cpus_allowed(p); + + if (p->sched_class->set_cpus_allowed) + p->sched_class->set_cpus_allowed(p, mask); + /* mask==cpumask_of(task_cpu(p)) which has a cpumask_weight==1 */ + p->nr_cpus_allowed = 1; + + /* Let migrate_enable know to fix things back up */ + p->migrate_disable |= MIGRATE_DISABLE_SET_AFFIN; +} + +void migrate_disable(void) +{ + struct task_struct *p = current; + + if (in_atomic()) { +#ifdef CONFIG_SCHED_DEBUG + p->migrate_disable_atomic++; +#endif + return; + } + +#ifdef CONFIG_SCHED_DEBUG + if (unlikely(p->migrate_disable_atomic)) { + tracing_off(); + WARN_ON_ONCE(1); + } +#endif + + if (p->migrate_disable) { + p->migrate_disable++; + return; + } + + preempt_disable(); + preempt_lazy_disable(); + pin_current_cpu(); + p->migrate_disable = 1; + preempt_enable(); +} +EXPORT_SYMBOL(migrate_disable); + +void migrate_enable(void) +{ + struct task_struct *p = current; + const struct cpumask *mask; + unsigned long flags; + struct rq *rq; + + if (in_atomic()) { +#ifdef CONFIG_SCHED_DEBUG + p->migrate_disable_atomic--; +#endif + return; + } + +#ifdef CONFIG_SCHED_DEBUG + if (unlikely(p->migrate_disable_atomic)) { + tracing_off(); + WARN_ON_ONCE(1); + } +#endif + WARN_ON_ONCE(p->migrate_disable <= 0); + + if (migrate_disable_count(p) > 1) { + p->migrate_disable--; + return; + } + + preempt_disable(); + if (unlikely(migrate_disabled_updated(p))) { + /* + * Undo whatever update_migrate_disable() did, also see there + * about locking. + */ + rq = this_rq(); + raw_spin_lock_irqsave(&rq->lock, flags); + + /* + * Clearing migrate_disable causes tsk_cpus_allowed to + * show the tasks original cpu affinity. + */ + p->migrate_disable = 0; + mask = tsk_cpus_allowed(p); + if (p->sched_class->set_cpus_allowed) + p->sched_class->set_cpus_allowed(p, mask); + p->nr_cpus_allowed = cpumask_weight(mask); + raw_spin_unlock_irqrestore(&rq->lock, flags); + } else + p->migrate_disable = 0; + + unpin_current_cpu(); + preempt_enable(); + preempt_lazy_enable(); +} +EXPORT_SYMBOL(migrate_enable); +#else +static inline void update_migrate_disable(struct task_struct *p) { } +#define migrate_disabled_updated(p) 0 +#endif + static void put_prev_task(struct rq *rq, struct task_struct *prev) { if (prev->on_rq || rq->skip_clock_update < 0) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2598 @ need_resched: smp_mb__before_spinlock(); raw_spin_lock_irq(&rq->lock); + update_migrate_disable(prev); + switch_count = &prev->nivcsw; if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) { if (unlikely(signal_pending_state(prev->state, prev))) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2607 @ need_resched: } else { deactivate_task(rq, prev, DEQUEUE_SLEEP); prev->on_rq = 0; - - /* - * If a worker went to sleep, notify and ask workqueue - * whether it wants to wake up a task to maintain - * concurrency. - */ - if (prev->flags & PF_WQ_WORKER) { - struct task_struct *to_wakeup; - - to_wakeup = wq_worker_sleeping(prev, cpu); - if (to_wakeup) - try_to_wake_up_local(to_wakeup); - } } switch_count = &prev->nvcsw; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2619 @ need_resched: put_prev_task(rq, prev); next = pick_next_task(rq); clear_tsk_need_resched(prev); + clear_tsk_need_resched_lazy(prev); rq->skip_clock_update = 0; if (likely(prev != next)) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2648 @ need_resched: static inline void sched_submit_work(struct task_struct *tsk) { - if (!tsk->state || tsk_is_pi_blocked(tsk)) + if (!tsk->state) + return; + /* + * If a worker went to sleep, notify and ask workqueue whether + * it wants to wake up a task to maintain concurrency. + */ + if (tsk->flags & PF_WQ_WORKER) + wq_worker_sleeping(tsk); + + + 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. @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2669 @ static inline void sched_submit_work(str blk_schedule_flush_plug(tsk); } +static inline void sched_update_worker(struct task_struct *tsk) +{ + if (tsk->flags & PF_WQ_WORKER) + wq_worker_running(tsk); +} + asmlinkage void __sched schedule(void) { struct task_struct *tsk = current; sched_submit_work(tsk); __schedule(); + sched_update_worker(tsk); } EXPORT_SYMBOL(schedule); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2727 @ asmlinkage void __sched notrace preempt_ if (likely(!preemptible())) return; +#ifdef CONFIG_PREEMPT_LAZY + /* + * Check for lazy preemption + */ + if (current_thread_info()->preempt_lazy_count && + !test_thread_flag(TIF_NEED_RESCHED)) + return; +#endif do { add_preempt_count_notrace(PREEMPT_ACTIVE); + /* + * The add/subtract must not be traced by the function + * tracer. But we still want to account for the + * preempt off latency tracer. Since the _notrace versions + * of add/subtract skip the accounting for latency tracer + * we must force it manually. + */ + start_critical_timings(); __schedule(); + stop_critical_timings(); sub_preempt_count_notrace(PREEMPT_ACTIVE); /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2919 @ void complete(struct completion *x) { unsigned long flags; - spin_lock_irqsave(&x->wait.lock, flags); + raw_spin_lock_irqsave(&x->wait.lock, flags); x->done++; - __wake_up_common(&x->wait, TASK_NORMAL, 1, 0, NULL); - spin_unlock_irqrestore(&x->wait.lock, flags); + __swait_wake_locked(&x->wait, TASK_NORMAL, 1); + raw_spin_unlock_irqrestore(&x->wait.lock, flags); } EXPORT_SYMBOL(complete); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2939 @ void complete_all(struct completion *x) { unsigned long flags; - spin_lock_irqsave(&x->wait.lock, flags); + raw_spin_lock_irqsave(&x->wait.lock, flags); x->done += UINT_MAX/2; - __wake_up_common(&x->wait, TASK_NORMAL, 0, 0, NULL); - spin_unlock_irqrestore(&x->wait.lock, flags); + __swait_wake_locked(&x->wait, TASK_NORMAL, 0); + raw_spin_unlock_irqrestore(&x->wait.lock, flags); } EXPORT_SYMBOL(complete_all); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2951 @ do_wait_for_common(struct completion *x, long (*action)(long), long timeout, int state) { if (!x->done) { - DECLARE_WAITQUEUE(wait, current); + DEFINE_SWAITER(wait); - __add_wait_queue_tail_exclusive(&x->wait, &wait); + swait_prepare_locked(&x->wait, &wait); do { if (signal_pending_state(state, current)) { timeout = -ERESTARTSYS; break; } __set_current_state(state); - spin_unlock_irq(&x->wait.lock); + raw_spin_unlock_irq(&x->wait.lock); timeout = action(timeout); - spin_lock_irq(&x->wait.lock); + raw_spin_lock_irq(&x->wait.lock); } while (!x->done && timeout); - __remove_wait_queue(&x->wait, &wait); + swait_finish_locked(&x->wait, &wait); if (!x->done) return timeout; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:2978 @ __wait_for_common(struct completion *x, { might_sleep(); - spin_lock_irq(&x->wait.lock); + raw_spin_lock_irq(&x->wait.lock); timeout = do_wait_for_common(x, action, timeout, state); - spin_unlock_irq(&x->wait.lock); + raw_spin_unlock_irq(&x->wait.lock); return timeout; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:3156 @ bool try_wait_for_completion(struct comp unsigned long flags; int ret = 1; - spin_lock_irqsave(&x->wait.lock, flags); + raw_spin_lock_irqsave(&x->wait.lock, flags); if (!x->done) ret = 0; else x->done--; - spin_unlock_irqrestore(&x->wait.lock, flags); + raw_spin_unlock_irqrestore(&x->wait.lock, flags); return ret; } EXPORT_SYMBOL(try_wait_for_completion); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:3179 @ bool completion_done(struct completion * unsigned long flags; int ret = 1; - spin_lock_irqsave(&x->wait.lock, flags); + raw_spin_lock_irqsave(&x->wait.lock, flags); if (!x->done) ret = 0; - spin_unlock_irqrestore(&x->wait.lock, flags); + raw_spin_unlock_irqrestore(&x->wait.lock, flags); return ret; } EXPORT_SYMBOL(completion_done); @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:3243 @ EXPORT_SYMBOL(sleep_on_timeout); * This function changes the 'effective' priority of a task. It does * not touch ->normal_prio like __setscheduler(). * - * Used by the rt_mutex code to implement priority inheritance logic. + * Used by the rt_mutex code to implement priority inheritance + * logic. Call site only calls if the priority of the task changed. */ void rt_mutex_setprio(struct task_struct *p, int prio) { @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:3475 @ static struct task_struct *find_process_ return pid ? find_task_by_vpid(pid) : current; } -/* Actually do priority change: must hold rq lock. */ -static void -__setscheduler(struct rq *rq, struct task_struct *p, int policy, int prio) +static void __setscheduler_params(struct task_struct *p, int policy, int prio) { p->policy = policy; p->rt_priority = prio; p->normal_prio = normal_prio(p); + set_load_weight(p); +} + +/* Actually do priority change: must hold rq lock. */ +static void +__setscheduler(struct rq *rq, struct task_struct *p, int policy, int prio) +{ + __setscheduler_params(p, policy, prio); /* we are holding p->pi_lock already */ p->prio = rt_mutex_getprio(p); if (rt_prio(p->prio)) p->sched_class = &rt_sched_class; else p->sched_class = &fair_sched_class; - set_load_weight(p); } /* @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:3515 @ static bool check_same_owner(struct task static int __sched_setscheduler(struct task_struct *p, int policy, const struct sched_param *param, bool user) { + int newprio = MAX_RT_PRIO - 1 - param->sched_priority; int retval, oldprio, oldpolicy = -1, on_rq, running; unsigned long flags; const struct sched_class *prev_class; @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:3611 @ recheck: } /* - * If not changing anything there's no need to proceed further: + * If not changing anything there's no need to proceed + * further, but store a possible modification of + * reset_on_fork. */ if (unlikely(policy == p->policy && (!rt_policy(policy) || param->sched_priority == p->rt_priority))) { + p->sched_reset_on_fork = reset_on_fork; task_rq_unlock(rq, p, &flags); return 0; } @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:3643 @ recheck: task_rq_unlock(rq, p, &flags); goto recheck; } + + p->sched_reset_on_fork = reset_on_fork; + oldprio = p->prio; + + /* + * Special case for priority boosted tasks. + * + * If the new priority is lower or equal (user space view) + * than the current (boosted) priority, we just store the new + * normal parameters and do not touch the scheduler class and + * the runqueue. This will be done when the task deboost + * itself. + */ + if (rt_mutex_check_prio(p, newprio)) { + __setscheduler_params(p, policy, param->sched_priority); + task_rq_unlock(rq, p, &flags); + return 0; + } + on_rq = p->on_rq; running = task_current(rq, p); if (on_rq) @ linux-3.12.19-rt30/Documentation/hwlat_detector.txt:3669 @ recheck: if (running) p->sched_class->put_prev_task(rq, p); - p