---
 Documentation/hwlat_detector.txt                     |   64 
 Documentation/sysrq.txt                              |   11 
 Documentation/trace/histograms.txt                   |  186 ++
 arch/Kconfig                                         |    1 
 arch/alpha/mm/fault.c                                |    2 
 arch/arm/Kconfig                                     |    1 
 arch/arm/include/asm/switch_to.h                     |    8 
 arch/arm/include/asm/thread_info.h                   |    3 
 arch/arm/kernel/asm-offsets.c                        |    1 
 arch/arm/kernel/entry-armv.S                         |   13 
 arch/arm/kernel/process.c                            |   24 
 arch/arm/kernel/signal.c                             |    3 
 arch/arm/kernel/unwind.c                             |   14 
 arch/arm/mach-at91/at91rm9200_time.c                 |    1 
 arch/arm/mach-at91/at91sam926x_time.c                |    5 
 arch/arm/mach-exynos/platsmp.c                       |   12 
 arch/arm/mach-msm/platsmp.c                          |   10 
 arch/arm/mach-omap2/omap-smp.c                       |   10 
 arch/arm/mach-prima2/platsmp.c                       |   10 
 arch/arm/mach-spear/platsmp.c                        |   10 
 arch/arm/mach-sti/platsmp.c                          |   10 
 arch/arm/mach-ux500/platsmp.c                        |   10 
 arch/arm/mm/fault.c                                  |    2 
 arch/arm/mm/highmem.c                                |   43 
 arch/arm/plat-versatile/platsmp.c                    |   10 
 arch/avr32/mm/fault.c                                |    2 
 arch/cris/mm/fault.c                                 |    2 
 arch/frv/mm/fault.c                                  |    2 
 arch/ia64/mm/fault.c                                 |    2 
 arch/m32r/mm/fault.c                                 |    2 
 arch/m68k/mm/fault.c                                 |    2 
 arch/microblaze/mm/fault.c                           |    2 
 arch/mips/Kconfig                                    |    2 
 arch/mips/kernel/signal.c                            |    1 
 arch/mips/mm/fault.c                                 |    2 
 arch/mn10300/mm/fault.c                              |    2 
 arch/parisc/mm/fault.c                               |    2 
 arch/powerpc/Kconfig                                 |    6 
 arch/powerpc/include/asm/thread_info.h               |   12 
 arch/powerpc/kernel/asm-offsets.c                    |    1 
 arch/powerpc/kernel/entry_32.S                       |   17 
 arch/powerpc/kernel/entry_64.S                       |   14 
 arch/powerpc/kernel/irq.c                            |    2 
 arch/powerpc/kernel/misc_32.S                        |    2 
 arch/powerpc/kernel/misc_64.S                        |    2 
 arch/powerpc/kernel/time.c                           |    2 
 arch/powerpc/mm/fault.c                              |    2 
 arch/powerpc/platforms/52xx/mpc52xx_pic.c            |    5 
 arch/s390/mm/fault.c                                 |    6 
 arch/score/mm/fault.c                                |    2 
 arch/sh/kernel/irq.c                                 |    2 
 arch/sh/mm/fault.c                                   |    2 
 arch/sparc/Kconfig                                   |   11 
 arch/sparc/include/asm/mmu_64.h                      |    2 
 arch/sparc/include/asm/mmu_context_64.h              |   10 
 arch/sparc/kernel/irq_64.c                           |    2 
 arch/sparc/kernel/pcr.c                              |    2 
 arch/sparc/kernel/setup_32.c                         |    1 
 arch/sparc/kernel/setup_64.c                         |    8 
 arch/sparc/kernel/smp_64.c                           |    4 
 arch/sparc/mm/fault_32.c                             |    2 
 arch/sparc/mm/fault_64.c                             |    2 
 arch/sparc/mm/init_64.c                              |   14 
 arch/sparc/mm/tsb.c                                  |   20 
 arch/tile/mm/fault.c                                 |    2 
 arch/um/kernel/trap.c                                |    2 
 arch/x86/Kconfig                                     |   10 
 arch/x86/crypto/aesni-intel_glue.c                   |   24 
 arch/x86/crypto/cast5_avx_glue.c                     |   21 
 arch/x86/crypto/glue_helper.c                        |   31 
 arch/x86/include/asm/signal.h                        |   13 
 arch/x86/include/asm/stackprotector.h                |   10 
 arch/x86/include/asm/thread_info.h                   |    6 
 arch/x86/kernel/apic/io_apic.c                       |    3 
 arch/x86/kernel/asm-offsets.c                        |    1 
 arch/x86/kernel/cpu/mcheck/mce.c                     |  131 +-
 arch/x86/kernel/entry_32.S                           |   18 
 arch/x86/kernel/entry_64.S                           |   26 
 arch/x86/kernel/irq_32.c                             |    2 
 arch/x86/kernel/irq_64.c                             |    3 
 arch/x86/kernel/irq_work.c                           |    2 
 arch/x86/kernel/process_32.c                         |   32 
 arch/x86/kernel/signal.c                             |    8 
 arch/x86/kernel/traps.c                              |   32 
 arch/x86/kvm/x86.c                                   |    7 
 arch/x86/mm/fault.c                                  |    2 
 arch/x86/mm/highmem_32.c                             |    9 
 arch/x86/mm/iomap_32.c                               |   11 
 arch/xtensa/mm/fault.c                               |    2 
 block/blk-core.c                                     |   14 
 block/blk-ioc.c                                      |    5 
 block/blk-iopoll.c                                   |    3 
 block/blk-softirq.c                                  |    3 
 crypto/algapi.c                                      |    4 
 crypto/api.c                                         |    6 
 crypto/internal.h                                    |    4 
 drivers/acpi/acpica/acglobal.h                       |    2 
 drivers/acpi/acpica/hwregs.c                         |    4 
 drivers/acpi/acpica/hwxface.c                        |    4 
 drivers/acpi/acpica/utmutex.c                        |    4 
 drivers/ata/libata-sff.c                             |   12 
 drivers/char/random.c                                |   19 
 drivers/clocksource/tcb_clksrc.c                     |   38 
 drivers/gpu/drm/drm_irq.c                            |    7 
 drivers/gpu/drm/i915/i915_gem.c                      |    2 
 drivers/gpu/drm/i915/i915_gem_execbuffer.c           |    2 
 drivers/i2c/busses/i2c-omap.c                        |    5 
 drivers/ide/alim15x3.c                               |    4 
 drivers/ide/hpt366.c                                 |    4 
 drivers/ide/ide-io-std.c                             |    8 
 drivers/ide/ide-io.c                                 |    2 
 drivers/ide/ide-iops.c                               |    4 
 drivers/ide/ide-probe.c                              |    4 
 drivers/ide/ide-taskfile.c                           |    6 
 drivers/infiniband/ulp/ipoib/ipoib_multicast.c       |    4 
 drivers/input/gameport/gameport.c                    |    8 
 drivers/leds/trigger/Kconfig                         |    2 
 drivers/md/bcache/Kconfig                            |    1 
 drivers/md/dm.c                                      |    4 
 drivers/md/raid5.c                                   |    7 
 drivers/md/raid5.h                                   |    1 
 drivers/misc/Kconfig                                 |   42 
 drivers/misc/Makefile                                |    1 
 drivers/misc/hwlat_detector.c                        | 1240 +++++++++++++++++++
 drivers/mmc/host/mmci.c                              |    5 
 drivers/net/Kconfig                                  |    1 
 drivers/net/ethernet/3com/3c59x.c                    |    8 
 drivers/net/ethernet/atheros/atl1c/atl1c_main.c      |    6 
 drivers/net/ethernet/atheros/atl1e/atl1e_main.c      |    3 
 drivers/net/ethernet/chelsio/cxgb/sge.c              |    3 
 drivers/net/ethernet/freescale/gianfar.c             |   36 
 drivers/net/ethernet/freescale/gianfar_ethtool.c     |    8 
 drivers/net/ethernet/freescale/gianfar_sysfs.c       |   24 
 drivers/net/ethernet/neterion/s2io.c                 |    7 
 drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c |    6 
 drivers/net/ethernet/realtek/8139too.c               |    2 
 drivers/net/ethernet/tehuti/tehuti.c                 |    9 
 drivers/net/rionet.c                                 |    6 
 drivers/net/wireless/iwlwifi/pcie/trans.c            |   19 
 drivers/net/wireless/orinoco/orinoco_usb.c           |    2 
 drivers/pci/access.c                                 |    2 
 drivers/scsi/fcoe/fcoe.c                             |   18 
 drivers/scsi/fcoe/fcoe_ctlr.c                        |    4 
 drivers/scsi/libfc/fc_exch.c                         |    4 
 drivers/scsi/qla2xxx/qla_inline.h                    |    4 
 drivers/tty/serial/8250/8250_core.c                  |   27 
 drivers/tty/serial/amba-pl011.c                      |   15 
 drivers/tty/serial/omap-serial.c                     |   12 
 drivers/tty/serial/sunhv.c                           |   22 
 drivers/tty/serial/sunsab.c                          |   14 
 drivers/tty/serial/sunsu.c                           |   14 
 drivers/tty/serial/sunzilog.c                        |   14 
 drivers/usb/core/hcd.c                               |    8 
 drivers/usb/gadget/f_fs.c                            |    2 
 drivers/usb/gadget/inode.c                           |    4 
 drivers/usb/host/ohci-hcd.c                          |   10 
 fs/autofs4/autofs_i.h                                |    1 
 fs/autofs4/expire.c                                  |    2 
 fs/buffer.c                                          |   21 
 fs/dcache.c                                          |    5 
 fs/eventpoll.c                                       |    4 
 fs/exec.c                                            |    2 
 fs/jbd/checkpoint.c                                  |    2 
 fs/jbd2/checkpoint.c                                 |    2 
 fs/namespace.c                                       |    8 
 fs/ntfs/aops.c                                       |   14 
 fs/timerfd.c                                         |    5 
 include/acpi/platform/aclinux.h                      |   14 
 include/asm-generic/bug.h                            |   14 
 include/linux/buffer_head.h                          |   44 
 include/linux/completion.h                           |    8 
 include/linux/cpu.h                                  |    4 
 include/linux/delay.h                                |    6 
 include/linux/ftrace_event.h                         |    3 
 include/linux/highmem.h                              |   28 
 include/linux/hrtimer.h                              |   19 
 include/linux/idr.h                                  |    4 
 include/linux/init_task.h                            |   10 
 include/linux/interrupt.h                            |   64 
 include/linux/irq.h                                  |    5 
 include/linux/irq_work.h                             |    1 
 include/linux/irqdesc.h                              |    1 
 include/linux/irqflags.h                             |   29 
 include/linux/jbd_common.h                           |   24 
 include/linux/jump_label.h                           |    3 
 include/linux/kdb.h                                  |    3 
 include/linux/kernel.h                               |    1 
 include/linux/lglock.h                               |   19 
 include/linux/list.h                                 |   11 
 include/linux/list_bl.h                              |   28 
 include/linux/locallock.h                            |  270 ++++
 include/linux/mm.h                                   |   46 
 include/linux/mm_types.h                             |    8 
 include/linux/mutex.h                                |   20 
 include/linux/mutex_rt.h                             |   84 +
 include/linux/netdevice.h                            |    3 
 include/linux/netfilter/x_tables.h                   |    7 
 include/linux/notifier.h                             |   34 
 include/linux/page_cgroup.h                          |   15 
 include/linux/percpu.h                               |   25 
 include/linux/pid.h                                  |    1 
 include/linux/preempt.h                              |   70 +
 include/linux/preempt_mask.h                         |   15 
 include/linux/printk.h                               |    3 
 include/linux/radix-tree.h                           |    7 
 include/linux/random.h                               |    2 
 include/linux/rcupdate.h                             |   26 
 include/linux/rcutree.h                              |   18 
 include/linux/rtmutex.h                              |   42 
 include/linux/rwlock_rt.h                            |   99 +
 include/linux/rwlock_types.h                         |    7 
 include/linux/rwlock_types_rt.h                      |   33 
 include/linux/rwsem.h                                |    6 
 include/linux/rwsem_rt.h                             |  128 +
 include/linux/sched.h                                |  207 +++
 include/linux/sched/rt.h                             |    5 
 include/linux/seqlock.h                              |   54 
 include/linux/signal.h                               |    1 
 include/linux/skbuff.h                               |    7 
 include/linux/smp.h                                  |    3 
 include/linux/spinlock.h                             |   12 
 include/linux/spinlock_api_smp.h                     |    4 
 include/linux/spinlock_rt.h                          |  166 ++
 include/linux/spinlock_types.h                       |   79 -
 include/linux/spinlock_types_nort.h                  |   33 
 include/linux/spinlock_types_raw.h                   |   56 
 include/linux/spinlock_types_rt.h                    |   51 
 include/linux/srcu.h                                 |    9 
 include/linux/sysctl.h                               |    1 
 include/linux/timer.h                                |    2 
 include/linux/uaccess.h                              |   41 
 include/linux/uprobes.h                              |    1 
 include/linux/vmstat.h                               |    4 
 include/linux/wait-simple.h                          |  207 +++
 include/linux/wait.h                                 |    1 
 include/net/dst.h                                    |    2 
 include/net/neighbour.h                              |    4 
 include/net/netns/ipv4.h                             |    1 
 include/trace/events/hist.h                          |   72 +
 include/trace/events/latency_hist.h                  |   29 
 init/Kconfig                                         |    7 
 init/Makefile                                        |    2 
 init/main.c                                          |    4 
 ipc/mqueue.c                                         |   24 
 ipc/msg.c                                            |   16 
 ipc/sem.c                                            |   10 
 kernel/Kconfig.locks                                 |    2 
 kernel/Kconfig.preempt                               |   33 
 kernel/Makefile                                      |   11 
 kernel/cpu.c                                         |  328 ++++-
 kernel/debug/kdb/kdb_io.c                            |    6 
 kernel/events/core.c                                 |    1 
 kernel/exit.c                                        |    2 
 kernel/fork.c                                        |   42 
 kernel/futex.c                                       |   82 -
 kernel/hrtimer.c                                     |  370 ++++-
 kernel/irq/handle.c                                  |    8 
 kernel/irq/manage.c                                  |  100 +
 kernel/irq/settings.h                                |   12 
 kernel/irq/spurious.c                                |    8 
 kernel/irq_work.c                                    |   27 
 kernel/itimer.c                                      |    1 
 kernel/ksysfs.c                                      |   12 
 kernel/lglock.c                                      |   54 
 kernel/lockdep.c                                     |    2 
 kernel/panic.c                                       |    2 
 kernel/posix-cpu-timers.c                            |  198 ++-
 kernel/posix-timers.c                                |   37 
 kernel/power/hibernate.c                             |    7 
 kernel/power/suspend.c                               |    4 
 kernel/printk/printk.c                               |  146 +-
 kernel/ptrace.c                                      |    7 
 kernel/rcupdate.c                                    |    2 
 kernel/rcutiny.c                                     |    2 
 kernel/rcutree.c                                     |  152 ++
 kernel/rcutree.h                                     |   11 
 kernel/rcutree_plugin.h                              |  178 --
 kernel/relay.c                                       |   14 
 kernel/res_counter.c                                 |    8 
 kernel/rt.c                                          |  456 ++++++
 kernel/rtmutex.c                                     |  743 ++++++++++-
 kernel/rtmutex_common.h                              |   12 
 kernel/sched/core.c                                  |  568 +++++++-
 kernel/sched/cputime.c                               |   62 
 kernel/sched/debug.c                                 |    7 
 kernel/sched/fair.c                                  |   16 
 kernel/sched/features.h                              |    7 
 kernel/sched/rt.c                                    |    1 
 kernel/sched/sched.h                                 |   10 
 kernel/signal.c                                      |  135 +-
 kernel/softirq.c                                     |  742 +++++++++--
 kernel/spinlock.c                                    |    7 
 kernel/stop_machine.c                                |   93 +
 kernel/time/jiffies.c                                |    7 
 kernel/time/ntp.c                                    |   40 
 kernel/time/tick-common.c                            |   10 
 kernel/time/tick-internal.h                          |    3 
 kernel/time/tick-sched.c                             |   27 
 kernel/time/timekeeping.c                            |    6 
 kernel/timer.c                                       |  152 ++
 kernel/trace/Kconfig                                 |  104 +
 kernel/trace/Makefile                                |    4 
 kernel/trace/latency_hist.c                          | 1178 ++++++++++++++++++
 kernel/trace/trace.c                                 |   44 
 kernel/trace/trace.h                                 |    2 
 kernel/trace/trace_events.c                          |    2 
 kernel/trace/trace_irqsoff.c                         |   11 
 kernel/trace/trace_output.c                          |   18 
 kernel/user.c                                        |    4 
 kernel/wait-simple.c                                 |  115 +
 kernel/watchdog.c                                    |   16 
 kernel/workqueue.c                                   |  223 ++-
 kernel/workqueue_internal.h                          |    5 
 lib/Kconfig                                          |    2 
 lib/Kconfig.debug                                    |    2 
 lib/Makefile                                         |    3 
 lib/debugobjects.c                                   |    5 
 lib/idr.c                                            |   37 
 lib/locking-selftest.c                               |   23 
 lib/percpu-rwsem.c                                   |    4 
 lib/radix-tree.c                                     |    5 
 lib/scatterlist.c                                    |    6 
 lib/smp_processor_id.c                               |    6 
 lib/spinlock_debug.c                                 |    5 
 localversion-rt                                      |    1 
 mm/Kconfig                                           |    2 
 mm/bounce.c                                          |    4 
 mm/filemap.c                                         |    2 
 mm/highmem.c                                         |    6 
 mm/memcontrol.c                                      |    4 
 mm/memory.c                                          |   58 
 mm/mmu_context.c                                     |    2 
 mm/page_alloc.c                                      |  145 +-
 mm/page_cgroup.c                                     |   11 
 mm/slab.h                                            |    4 
 mm/slub.c                                            |  126 +
 mm/swap.c                                            |   34 
 mm/vmalloc.c                                         |   13 
 mm/vmstat.c                                          |    6 
 net/core/dev.c                                       |  112 +
 net/core/skbuff.c                                    |    6 
 net/core/sock.c                                      |    3 
 net/ipv4/icmp.c                                      |   30 
 net/ipv4/ip_output.c                                 |    8 
 net/ipv4/sysctl_net_ipv4.c                           |    7 
 net/mac80211/rx.c                                    |    2 
 net/netfilter/core.c                                 |    6 
 net/packet/af_packet.c                               |    5 
 net/rds/ib_rdma.c                                    |    3 
 net/sched/sch_generic.c                              |    2 
 scripts/mkcompile_h                                  |    4 
 351 files changed, 11017 insertions(+), 1728 deletions(-)

Index: linux-3.12.24-rt37/Documentation/hwlat_detector.txt
===================================================================
--- /dev/null
+++ linux-3.12.24-rt37/Documentation/hwlat_detector.txt
@@ -0,0 +1,64 @@
+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-3.12.24-rt37/Documentation/sysrq.txt
===================================================================
--- linux-3.12.24-rt37.orig/Documentation/sysrq.txt
+++ linux-3.12.24-rt37/Documentation/sysrq.txt
@@ -57,10 +57,17 @@ 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-3.12.24-rt37/Documentation/trace/histograms.txt
===================================================================
--- /dev/null
+++ linux-3.12.24-rt37/Documentation/trace/histograms.txt
@@ -0,0 +1,186 @@
+               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-3.12.24-rt37/arch/Kconfig
===================================================================
--- linux-3.12.24-rt37.orig/arch/Kconfig
+++ linux-3.12.24-rt37/arch/Kconfig
@@ -6,6 +6,7 @@ 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-3.12.24-rt37/arch/alpha/mm/fault.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/alpha/mm/fault.c
+++ linux-3.12.24-rt37/arch/alpha/mm/fault.c
@@ -107,7 +107,7 @@ 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-3.12.24-rt37/arch/arm/Kconfig
===================================================================
--- linux-3.12.24-rt37.orig/arch/arm/Kconfig
+++ linux-3.12.24-rt37/arch/arm/Kconfig
@@ -51,6 +51,7 @@ 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-3.12.24-rt37/arch/arm/include/asm/switch_to.h
===================================================================
--- linux-3.12.24-rt37.orig/arch/arm/include/asm/switch_to.h
+++ linux-3.12.24-rt37/arch/arm/include/asm/switch_to.h
@@ -3,6 +3,13 @@
 
 #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
@@ -22,6 +29,7 @@ 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-3.12.24-rt37/arch/arm/include/asm/thread_info.h
===================================================================
--- linux-3.12.24-rt37.orig/arch/arm/include/asm/thread_info.h
+++ linux-3.12.24-rt37/arch/arm/include/asm/thread_info.h
@@ -60,6 +60,7 @@ 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 */
@@ -159,6 +160,7 @@ 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
@@ -171,6 +173,7 @@ 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-3.12.24-rt37/arch/arm/kernel/asm-offsets.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/arm/kernel/asm-offsets.c
+++ linux-3.12.24-rt37/arch/arm/kernel/asm-offsets.c
@@ -54,6 +54,7 @@ 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-3.12.24-rt37/arch/arm/kernel/entry-armv.S
===================================================================
--- linux-3.12.24-rt37.orig/arch/arm/kernel/entry-armv.S
+++ linux-3.12.24-rt37/arch/arm/kernel/entry-armv.S
@@ -205,11 +205,18 @@ __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
@@ -224,6 +231,8 @@ 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-3.12.24-rt37/arch/arm/kernel/process.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/arm/kernel/process.c
+++ linux-3.12.24-rt37/arch/arm/kernel/process.c
@@ -432,6 +432,30 @@ 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-3.12.24-rt37/arch/arm/kernel/signal.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/arm/kernel/signal.c
+++ linux-3.12.24-rt37/arch/arm/kernel/signal.c
@@ -589,7 +589,8 @@ 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-3.12.24-rt37/arch/arm/kernel/unwind.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/arm/kernel/unwind.c
+++ linux-3.12.24-rt37/arch/arm/kernel/unwind.c
@@ -87,7 +87,7 @@ 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 */
@@ -195,7 +195,7 @@ 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) {
@@ -207,7 +207,7 @@ 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);
@@ -469,9 +469,9 @@ 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;
 }
@@ -483,9 +483,9 @@ 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-3.12.24-rt37/arch/arm/mach-at91/at91rm9200_time.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/arm/mach-at91/at91rm9200_time.c
+++ linux-3.12.24-rt37/arch/arm/mach-at91/at91rm9200_time.c
@@ -134,6 +134,7 @@ 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-3.12.24-rt37/arch/arm/mach-at91/at91sam926x_time.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/arm/mach-at91/at91sam926x_time.c
+++ linux-3.12.24-rt37/arch/arm/mach-at91/at91sam926x_time.c
@@ -77,7 +77,7 @@ 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)
  */
@@ -86,6 +86,8 @@ 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
@@ -98,6 +100,7 @@ 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-3.12.24-rt37/arch/arm/mach-exynos/platsmp.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/arm/mach-exynos/platsmp.c
+++ linux-3.12.24-rt37/arch/arm/mach-exynos/platsmp.c
@@ -73,7 +73,7 @@ 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)
 {
@@ -86,8 +86,8 @@ 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)
@@ -99,7 +99,7 @@ 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
@@ -128,7 +128,7 @@ 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;
                }
        }
@@ -167,7 +167,7 @@ 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-3.12.24-rt37/arch/arm/mach-msm/platsmp.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/arm/mach-msm/platsmp.c
+++ linux-3.12.24-rt37/arch/arm/mach-msm/platsmp.c
@@ -30,7 +30,7 @@
 
 extern void msm_secondary_startup(void);
 
-static DEFINE_SPINLOCK(boot_lock);
+static DEFINE_RAW_SPINLOCK(boot_lock);
 
 static inline int get_core_count(void)
 {
@@ -50,8 +50,8 @@ 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)
@@ -88,7 +88,7 @@ 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
@@ -122,7 +122,7 @@ 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-3.12.24-rt37/arch/arm/mach-omap2/omap-smp.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/arm/mach-omap2/omap-smp.c
+++ linux-3.12.24-rt37/arch/arm/mach-omap2/omap-smp.c
@@ -44,7 +44,7 @@ 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)
 {
@@ -68,8 +68,8 @@ 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)
@@ -83,7 +83,7 @@ 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.
@@ -160,7 +160,7 @@ 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-3.12.24-rt37/arch/arm/mach-prima2/platsmp.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/arm/mach-prima2/platsmp.c
+++ linux-3.12.24-rt37/arch/arm/mach-prima2/platsmp.c
@@ -23,7 +23,7 @@
 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,
@@ -56,8 +56,8 @@ 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[]  = {
@@ -95,7 +95,7 @@ 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
@@ -128,7 +128,7 @@ 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-3.12.24-rt37/arch/arm/mach-spear/platsmp.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/arm/mach-spear/platsmp.c
+++ linux-3.12.24-rt37/arch/arm/mach-spear/platsmp.c
@@ -20,7 +20,7 @@
 #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);
 
@@ -36,8 +36,8 @@ 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)
@@ -48,7 +48,7 @@ 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
@@ -75,7 +75,7 @@ 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-3.12.24-rt37/arch/arm/mach-sti/platsmp.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/arm/mach-sti/platsmp.c
+++ linux-3.12.24-rt37/arch/arm/mach-sti/platsmp.c
@@ -35,7 +35,7 @@ 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)
 {
@@ -50,8 +50,8 @@ 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)
@@ -62,7 +62,7 @@ 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
@@ -93,7 +93,7 @@ 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-3.12.24-rt37/arch/arm/mach-ux500/platsmp.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/arm/mach-ux500/platsmp.c
+++ linux-3.12.24-rt37/arch/arm/mach-ux500/platsmp.c
@@ -52,7 +52,7 @@ 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)
 {
@@ -65,8 +65,8 @@ 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)
@@ -77,7 +77,7 @@ 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
@@ -98,7 +98,7 @@ 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-3.12.24-rt37/arch/arm/mm/fault.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/arm/mm/fault.c
+++ linux-3.12.24-rt37/arch/arm/mm/fault.c
@@ -277,7 +277,7 @@ 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-3.12.24-rt37/arch/arm/mm/highmem.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/arm/mm/highmem.c
+++ linux-3.12.24-rt37/arch/arm/mm/highmem.c
@@ -38,6 +38,7 @@ 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;
@@ -76,7 +77,10 @@ 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;
 }
@@ -93,12 +97,15 @@ 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() */
@@ -110,6 +117,7 @@ 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;
 
@@ -121,7 +129,10 @@ 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;
 }
@@ -135,3 +146,29 @@ 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-3.12.24-rt37/arch/arm/plat-versatile/platsmp.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/arm/plat-versatile/platsmp.c
+++ linux-3.12.24-rt37/arch/arm/plat-versatile/platsmp.c
@@ -31,7 +31,7 @@ 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)
 {
@@ -44,8 +44,8 @@ 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)
@@ -56,7 +56,7 @@ 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
@@ -86,7 +86,7 @@ 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-3.12.24-rt37/arch/avr32/mm/fault.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/avr32/mm/fault.c
+++ linux-3.12.24-rt37/arch/avr32/mm/fault.c
@@ -81,7 +81,7 @@ 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-3.12.24-rt37/arch/cris/mm/fault.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/cris/mm/fault.c
+++ linux-3.12.24-rt37/arch/cris/mm/fault.c
@@ -113,7 +113,7 @@ 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-3.12.24-rt37/arch/frv/mm/fault.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/frv/mm/fault.c
+++ linux-3.12.24-rt37/arch/frv/mm/fault.c
@@ -78,7 +78,7 @@ 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-3.12.24-rt37/arch/ia64/mm/fault.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/ia64/mm/fault.c
+++ linux-3.12.24-rt37/arch/ia64/mm/fault.c
@@ -96,7 +96,7 @@ 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-3.12.24-rt37/arch/m32r/mm/fault.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/m32r/mm/fault.c
+++ linux-3.12.24-rt37/arch/m32r/mm/fault.c
@@ -114,7 +114,7 @@ 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-3.12.24-rt37/arch/m68k/mm/fault.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/m68k/mm/fault.c
+++ linux-3.12.24-rt37/arch/m68k/mm/fault.c
@@ -85,7 +85,7 @@ 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-3.12.24-rt37/arch/microblaze/mm/fault.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/microblaze/mm/fault.c
+++ linux-3.12.24-rt37/arch/microblaze/mm/fault.c
@@ -107,7 +107,7 @@ 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-3.12.24-rt37/arch/mips/Kconfig
===================================================================
--- linux-3.12.24-rt37.orig/arch/mips/Kconfig
+++ linux-3.12.24-rt37/arch/mips/Kconfig
@@ -2078,7 +2078,7 @@ 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-3.12.24-rt37/arch/mips/kernel/signal.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/mips/kernel/signal.c
+++ linux-3.12.24-rt37/arch/mips/kernel/signal.c
@@ -573,6 +573,7 @@ asmlinkage void do_notify_resume(struct
        __u32 thread_info_flags)
 {
        local_irq_enable();
+       preempt_check_resched();
 
        user_exit();
 
Index: linux-3.12.24-rt37/arch/mips/mm/fault.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/mips/mm/fault.c
+++ linux-3.12.24-rt37/arch/mips/mm/fault.c
@@ -89,7 +89,7 @@ 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-3.12.24-rt37/arch/mn10300/mm/fault.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/mn10300/mm/fault.c
+++ linux-3.12.24-rt37/arch/mn10300/mm/fault.c
@@ -168,7 +168,7 @@ 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-3.12.24-rt37/arch/parisc/mm/fault.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/parisc/mm/fault.c
+++ linux-3.12.24-rt37/arch/parisc/mm/fault.c
@@ -177,7 +177,7 @@ 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-3.12.24-rt37/arch/powerpc/Kconfig
===================================================================
--- linux-3.12.24-rt37.orig/arch/powerpc/Kconfig
+++ linux-3.12.24-rt37/arch/powerpc/Kconfig
@@ -60,10 +60,11 @@ 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
@@ -131,6 +132,7 @@ 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
@@ -285,7 +287,7 @@ 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-3.12.24-rt37/arch/powerpc/include/asm/thread_info.h
===================================================================
--- linux-3.12.24-rt37.orig/arch/powerpc/include/asm/thread_info.h
+++ linux-3.12.24-rt37/arch/powerpc/include/asm/thread_info.h
@@ -43,6 +43,8 @@ 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 */
 
@@ -90,8 +92,7 @@ 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 */
@@ -107,6 +108,8 @@ 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)
@@ -126,13 +129,16 @@ 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-3.12.24-rt37/arch/powerpc/kernel/asm-offsets.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/powerpc/kernel/asm-offsets.c
+++ linux-3.12.24-rt37/arch/powerpc/kernel/asm-offsets.c
@@ -165,6 +165,7 @@ 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-3.12.24-rt37/arch/powerpc/kernel/entry_32.S
===================================================================
--- linux-3.12.24-rt37.orig/arch/powerpc/kernel/entry_32.S
+++ linux-3.12.24-rt37/arch/powerpc/kernel/entry_32.S
@@ -890,7 +890,14 @@ 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 */
@@ -901,11 +908,11 @@ 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
@@ -1226,7 +1233,7 @@ 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 */
@@ -1247,7 +1254,7 @@ 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-3.12.24-rt37/arch/powerpc/kernel/entry_64.S
===================================================================
--- linux-3.12.24-rt37.orig/arch/powerpc/kernel/entry_64.S
+++ linux-3.12.24-rt37/arch/powerpc/kernel/entry_64.S
@@ -659,7 +659,7 @@ _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
@@ -709,10 +709,18 @@ 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
@@ -729,7 +737,7 @@ 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-3.12.24-rt37/arch/powerpc/kernel/irq.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/powerpc/kernel/irq.c
+++ linux-3.12.24-rt37/arch/powerpc/kernel/irq.c
@@ -594,6 +594,7 @@ void irq_ctx_init(void)
        }
 }
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 static inline void do_softirq_onstack(void)
 {
        struct thread_info *curtp, *irqtp;
@@ -626,6 +627,7 @@ void do_softirq(void)
 
        local_irq_restore(flags);
 }
+#endif
 
 irq_hw_number_t virq_to_hw(unsigned int virq)
 {
Index: linux-3.12.24-rt37/arch/powerpc/kernel/misc_32.S
===================================================================
--- linux-3.12.24-rt37.orig/arch/powerpc/kernel/misc_32.S
+++ linux-3.12.24-rt37/arch/powerpc/kernel/misc_32.S
@@ -40,6 +40,7 @@
  * 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)
@@ -56,6 +57,7 @@ _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-3.12.24-rt37/arch/powerpc/kernel/misc_64.S
===================================================================
--- linux-3.12.24-rt37.orig/arch/powerpc/kernel/misc_64.S
+++ linux-3.12.24-rt37/arch/powerpc/kernel/misc_64.S
@@ -29,6 +29,7 @@
 
        .text
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 _GLOBAL(call_do_softirq)
        mflr    r0
        std     r0,16(r1)
@@ -39,6 +40,7 @@ _GLOBAL(call_do_softirq)
        ld      r0,16(r1)
        mtlr    r0
        blr
+#endif
 
 _GLOBAL(call_do_irq)
        mflr    r0
Index: linux-3.12.24-rt37/arch/powerpc/kernel/time.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/powerpc/kernel/time.c
+++ linux-3.12.24-rt37/arch/powerpc/kernel/time.c
@@ -423,7 +423,7 @@ 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-3.12.24-rt37/arch/powerpc/mm/fault.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/powerpc/mm/fault.c
+++ linux-3.12.24-rt37/arch/powerpc/mm/fault.c
@@ -261,7 +261,7 @@ 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-3.12.24-rt37/arch/powerpc/platforms/52xx/mpc52xx_pic.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/powerpc/platforms/52xx/mpc52xx_pic.c
+++ linux-3.12.24-rt37/arch/powerpc/platforms/52xx/mpc52xx_pic.c
@@ -340,7 +340,7 @@ 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;
@@ -373,9 +373,8 @@ 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-3.12.24-rt37/arch/s390/mm/fault.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/s390/mm/fault.c
+++ linux-3.12.24-rt37/arch/s390/mm/fault.c
@@ -296,7 +296,8 @@ 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;
@@ -442,7 +443,8 @@ 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-3.12.24-rt37/arch/score/mm/fault.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/score/mm/fault.c
+++ linux-3.12.24-rt37/arch/score/mm/fault.c
@@ -73,7 +73,7 @@ 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-3.12.24-rt37/arch/sh/kernel/irq.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/sh/kernel/irq.c
+++ linux-3.12.24-rt37/arch/sh/kernel/irq.c
@@ -149,6 +149,7 @@ void irq_ctx_exit(int cpu)
        hardirq_ctx[cpu] = NULL;
 }
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 asmlinkage void do_softirq(void)
 {
        unsigned long flags;
@@ -191,6 +192,7 @@ asmlinkage void do_softirq(void)
 
        local_irq_restore(flags);
 }
+#endif
 #else
 static inline void handle_one_irq(unsigned int irq)
 {
Index: linux-3.12.24-rt37/arch/sh/mm/fault.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/sh/mm/fault.c
+++ linux-3.12.24-rt37/arch/sh/mm/fault.c
@@ -438,7 +438,7 @@ 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-3.12.24-rt37/arch/sparc/Kconfig
===================================================================
--- linux-3.12.24-rt37.orig/arch/sparc/Kconfig
+++ linux-3.12.24-rt37/arch/sparc/Kconfig
@@ -26,6 +26,7 @@ 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
@@ -177,12 +178,10 @@ 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
@@ -523,6 +522,10 @@ menu "Executable file formats"
 
 source "fs/Kconfig.binfmt"
 
+config EARLY_PRINTK
+       bool
+       default y
+
 config COMPAT
        bool
        depends on SPARC64
Index: linux-3.12.24-rt37/arch/sparc/include/asm/mmu_64.h
===================================================================
--- linux-3.12.24-rt37.orig/arch/sparc/include/asm/mmu_64.h
+++ linux-3.12.24-rt37/arch/sparc/include/asm/mmu_64.h
@@ -90,7 +90,7 @@ 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-3.12.24-rt37/arch/sparc/include/asm/mmu_context_64.h
===================================================================
--- linux-3.12.24-rt37.orig/arch/sparc/include/asm/mmu_context_64.h
+++ linux-3.12.24-rt37/arch/sparc/include/asm/mmu_context_64.h
@@ -13,7 +13,7 @@ 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[];
 
@@ -77,7 +77,7 @@ 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);
@@ -125,7 +125,7 @@ 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)
@@ -136,7 +136,7 @@ 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();
@@ -146,7 +146,7 @@ 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-3.12.24-rt37/arch/sparc/kernel/irq_64.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/sparc/kernel/irq_64.c
+++ linux-3.12.24-rt37/arch/sparc/kernel/irq_64.c
@@ -698,6 +698,7 @@ 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;
@@ -723,6 +724,7 @@ void do_softirq(void)
 
        local_irq_restore(flags);
 }
+#endif
 
 #ifdef CONFIG_HOTPLUG_CPU
 void fixup_irqs(void)
Index: linux-3.12.24-rt37/arch/sparc/kernel/pcr.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/sparc/kernel/pcr.c
+++ linux-3.12.24-rt37/arch/sparc/kernel/pcr.c
@@ -43,10 +43,12 @@ 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-3.12.24-rt37/arch/sparc/kernel/setup_32.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/sparc/kernel/setup_32.c
+++ linux-3.12.24-rt37/arch/sparc/kernel/setup_32.c
@@ -309,6 +309,7 @@ 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-3.12.24-rt37/arch/sparc/kernel/setup_64.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/sparc/kernel/setup_64.c
+++ linux-3.12.24-rt37/arch/sparc/kernel/setup_64.c
@@ -555,6 +555,12 @@ 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. */
@@ -566,7 +572,7 @@ 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-3.12.24-rt37/arch/sparc/kernel/smp_64.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/sparc/kernel/smp_64.c
+++ linux-3.12.24-rt37/arch/sparc/kernel/smp_64.c
@@ -976,12 +976,12 @@ 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-3.12.24-rt37/arch/sparc/mm/fault_32.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/sparc/mm/fault_32.c
+++ linux-3.12.24-rt37/arch/sparc/mm/fault_32.c
@@ -199,7 +199,7 @@ 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-3.12.24-rt37/arch/sparc/mm/fault_64.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/sparc/mm/fault_64.c
+++ linux-3.12.24-rt37/arch/sparc/mm/fault_64.c
@@ -322,7 +322,7 @@ 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-3.12.24-rt37/arch/sparc/mm/init_64.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/sparc/mm/init_64.c
+++ linux-3.12.24-rt37/arch/sparc/mm/init_64.c
@@ -350,7 +350,7 @@ void update_mmu_cache(struct vm_area_str
 
        mm = vma->vm_mm;
 
-       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))
@@ -361,7 +361,7 @@ 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)
@@ -661,7 +661,7 @@ 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)
@@ -683,7 +683,7 @@ 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);
@@ -719,7 +719,7 @@ 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();
@@ -2721,7 +2721,7 @@ 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;
@@ -2742,7 +2742,7 @@ 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-3.12.24-rt37/arch/sparc/mm/tsb.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/sparc/mm/tsb.c
+++ linux-3.12.24-rt37/arch/sparc/mm/tsb.c
@@ -73,7 +73,7 @@ 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;
@@ -90,14 +90,14 @@ 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;
@@ -114,7 +114,7 @@ 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
@@ -392,7 +392,7 @@ 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 =
@@ -407,7 +407,7 @@ 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;
@@ -433,7 +433,7 @@ 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().
@@ -459,7 +459,7 @@ 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;
 
@@ -523,12 +523,12 @@ 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-3.12.24-rt37/arch/tile/mm/fault.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/tile/mm/fault.c
+++ linux-3.12.24-rt37/arch/tile/mm/fault.c
@@ -357,7 +357,7 @@ 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-3.12.24-rt37/arch/um/kernel/trap.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/um/kernel/trap.c
+++ linux-3.12.24-rt37/arch/um/kernel/trap.c
@@ -38,7 +38,7 @@ 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-3.12.24-rt37/arch/x86/Kconfig
===================================================================
--- linux-3.12.24-rt37.orig/arch/x86/Kconfig
+++ linux-3.12.24-rt37/arch/x86/Kconfig
@@ -21,6 +21,7 @@ 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
@@ -179,8 +180,11 @@ 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
@@ -470,7 +474,7 @@ 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.
@@ -817,7 +821,7 @@ 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-3.12.24-rt37/arch/x86/crypto/aesni-intel_glue.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/x86/crypto/aesni-intel_glue.c
+++ linux-3.12.24-rt37/arch/x86/crypto/aesni-intel_glue.c
@@ -252,14 +252,14 @@ 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;
 }
@@ -276,14 +276,14 @@ 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;
 }
@@ -300,14 +300,14 @@ 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;
 }
@@ -324,14 +324,14 @@ 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;
 }
@@ -364,18 +364,20 @@ 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-3.12.24-rt37/arch/x86/crypto/cast5_avx_glue.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/x86/crypto/cast5_avx_glue.c
+++ linux-3.12.24-rt37/arch/x86/crypto/cast5_avx_glue.c
@@ -60,7 +60,7 @@ 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;
@@ -76,7 +76,7 @@ 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) {
@@ -104,10 +104,9 @@ 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;
 }
 
@@ -231,7 +230,7 @@ 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;
 
@@ -240,12 +239,11 @@ 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;
 }
 
@@ -315,7 +313,7 @@ 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;
 
@@ -324,13 +322,12 @@ 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-3.12.24-rt37/arch/x86/crypto/glue_helper.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/x86/crypto/glue_helper.c
+++ linux-3.12.24-rt37/arch/x86/crypto/glue_helper.c
@@ -39,7 +39,7 @@ 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);
@@ -49,7 +49,7 @@ 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;
@@ -71,10 +71,10 @@ 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;
 }
 
@@ -194,7 +194,7 @@ 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;
 
@@ -203,12 +203,12 @@ 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);
@@ -278,7 +278,7 @@ 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;
 
@@ -287,13 +287,12 @@ 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);
@@ -348,7 +347,7 @@ 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;
 
@@ -361,21 +360,21 @@ 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-3.12.24-rt37/arch/x86/include/asm/signal.h
===================================================================
--- linux-3.12.24-rt37.orig/arch/x86/include/asm/signal.h
+++ linux-3.12.24-rt37/arch/x86/include/asm/signal.h
@@ -23,6 +23,19 @@ 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-3.12.24-rt37/arch/x86/include/asm/stackprotector.h
===================================================================
--- linux-3.12.24-rt37.orig/arch/x86/include/asm/stackprotector.h
+++ linux-3.12.24-rt37/arch/x86/include/asm/stackprotector.h
@@ -57,7 +57,7 @@
  */
 static __always_inline void boot_init_stack_canary(void)
 {
-       u64 canary;
+       u64 uninitialized_var(canary);
        u64 tsc;
 
 #ifdef CONFIG_X86_64
@@ -68,8 +68,16 @@ 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-3.12.24-rt37/arch/x86/include/asm/thread_info.h
===================================================================
--- linux-3.12.24-rt37.orig/arch/x86/include/asm/thread_info.h
+++ linux-3.12.24-rt37/arch/x86/include/asm/thread_info.h
@@ -30,6 +30,8 @@ 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;
@@ -81,6 +83,7 @@ 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 */
@@ -105,6 +108,7 @@ 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)
@@ -154,6 +158,8 @@ 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-3.12.24-rt37/arch/x86/kernel/apic/io_apic.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/x86/kernel/apic/io_apic.c
+++ linux-3.12.24-rt37/arch/x86/kernel/apic/io_apic.c
@@ -2396,7 +2396,8 @@ 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-3.12.24-rt37/arch/x86/kernel/asm-offsets.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/x86/kernel/asm-offsets.c
+++ linux-3.12.24-rt37/arch/x86/kernel/asm-offsets.c
@@ -33,6 +33,7 @@ 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-3.12.24-rt37/arch/x86/kernel/cpu/mcheck/mce.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/x86/kernel/cpu/mcheck/mce.c
+++ linux-3.12.24-rt37/arch/x86/kernel/cpu/mcheck/mce.c
@@ -18,6 +18,7 @@
 #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>
@@ -41,6 +42,7 @@
 #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>
@@ -1268,7 +1270,7 @@ 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)
 {
@@ -1278,13 +1280,10 @@ 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));
@@ -1305,9 +1304,11 @@ 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;
 }
 
 /*
@@ -1315,28 +1316,37 @@ 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)
@@ -1346,6 +1356,63 @@ 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
@@ -1353,19 +1420,8 @@ 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;
@@ -1636,7 +1692,7 @@ 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);
 
@@ -1645,16 +1701,17 @@ 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);
 }
 
@@ -2329,6 +2386,8 @@ 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++) {
@@ -2355,6 +2414,7 @@ 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. */
@@ -2362,7 +2422,6 @@ 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:
@@ -2378,11 +2437,9 @@ 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;
        }
 
@@ -2444,6 +2501,8 @@ 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-3.12.24-rt37/arch/x86/kernel/entry_32.S
===================================================================
--- linux-3.12.24-rt37.orig/arch/x86/kernel/entry_32.S
+++ linux-3.12.24-rt37/arch/x86/kernel/entry_32.S
@@ -364,14 +364,22 @@ 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
@@ -603,7 +611,7 @@ 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
@@ -616,7 +624,7 @@ 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-3.12.24-rt37/arch/x86/kernel/entry_64.S
===================================================================
--- linux-3.12.24-rt37.orig/arch/x86/kernel/entry_64.S
+++ linux-3.12.24-rt37/arch/x86/kernel/entry_64.S
@@ -658,8 +658,8 @@ 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
@@ -771,8 +771,8 @@ 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
@@ -1071,8 +1071,8 @@ 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
@@ -1105,9 +1105,15 @@ 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
@@ -1341,6 +1347,7 @@ bad_gs:
        jmp  2b
        .previous
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 /* Call softirq on interrupt stack. Interrupts are off. */
 ENTRY(call_softirq)
        CFI_STARTPROC
@@ -1360,6 +1367,7 @@ ENTRY(call_softirq)
        ret
        CFI_ENDPROC
 END(call_softirq)
+#endif
 
 #ifdef CONFIG_XEN
 zeroentry xen_hypervisor_callback xen_do_hypervisor_callback
@@ -1529,7 +1537,7 @@ 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-3.12.24-rt37/arch/x86/kernel/irq_32.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/x86/kernel/irq_32.c
+++ linux-3.12.24-rt37/arch/x86/kernel/irq_32.c
@@ -149,6 +149,7 @@ 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;
@@ -179,6 +180,7 @@ asmlinkage void do_softirq(void)
 
        local_irq_restore(flags);
 }
+#endif
 
 bool handle_irq(unsigned irq, struct pt_regs *regs)
 {
Index: linux-3.12.24-rt37/arch/x86/kernel/irq_64.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/x86/kernel/irq_64.c
+++ linux-3.12.24-rt37/arch/x86/kernel/irq_64.c
@@ -88,7 +88,7 @@ bool handle_irq(unsigned irq, struct pt_
        return true;
 }
 
-
+#ifndef CONFIG_PREEMPT_RT_FULL
 extern void call_softirq(void);
 
 asmlinkage void do_softirq(void)
@@ -108,3 +108,4 @@ asmlinkage void do_softirq(void)
        }
        local_irq_restore(flags);
 }
+#endif
Index: linux-3.12.24-rt37/arch/x86/kernel/irq_work.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/x86/kernel/irq_work.c
+++ linux-3.12.24-rt37/arch/x86/kernel/irq_work.c
@@ -38,6 +38,7 @@ __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
@@ -48,3 +49,4 @@ void arch_irq_work_raise(void)
        apic_wait_icr_idle();
 #endif
 }
+#endif
Index: linux-3.12.24-rt37/arch/x86/kernel/process_32.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/x86/kernel/process_32.c
+++ linux-3.12.24-rt37/arch/x86/kernel/process_32.c
@@ -36,6 +36,7 @@
 #include <linux/uaccess.h>
 #include <linux/io.h>
 #include <linux/kdebug.h>
+#include <linux/highmem.h>
 
 #include <asm/pgtable.h>
 #include <asm/ldt.h>
@@ -219,6 +220,35 @@ 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.
@@ -298,6 +328,8 @@ __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-3.12.24-rt37/arch/x86/kernel/signal.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/x86/kernel/signal.c
+++ linux-3.12.24-rt37/arch/x86/kernel/signal.c
@@ -739,6 +739,14 @@ 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-3.12.24-rt37/arch/x86/kernel/traps.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/x86/kernel/traps.c
+++ linux-3.12.24-rt37/arch/x86/kernel/traps.c
@@ -86,9 +86,21 @@ 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();
 }
@@ -99,11 +111,13 @@ 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
@@ -236,9 +250,9 @@ 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);
 }
@@ -347,9 +361,9 @@ 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);
@@ -455,12 +469,12 @@ 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;
        }
@@ -480,7 +494,7 @@ 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-3.12.24-rt37/arch/x86/kvm/x86.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/x86/kvm/x86.c
+++ linux-3.12.24-rt37/arch/x86/kvm/x86.c
@@ -5492,6 +5492,13 @@ 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-3.12.24-rt37/arch/x86/mm/fault.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/x86/mm/fault.c
+++ linux-3.12.24-rt37/arch/x86/mm/fault.c
@@ -1098,7 +1098,7 @@ __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-3.12.24-rt37/arch/x86/mm/highmem_32.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/x86/mm/highmem_32.c
+++ linux-3.12.24-rt37/arch/x86/mm/highmem_32.c
@@ -32,6 +32,7 @@ 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;
 
@@ -45,7 +46,10 @@ 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;
@@ -88,6 +92,9 @@ 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-3.12.24-rt37/arch/x86/mm/iomap_32.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/x86/mm/iomap_32.c
+++ linux-3.12.24-rt37/arch/x86/mm/iomap_32.c
@@ -56,6 +56,7 @@ 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;
 
@@ -64,7 +65,12 @@ 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;
@@ -110,6 +116,9 @@ 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-3.12.24-rt37/arch/xtensa/mm/fault.c
===================================================================
--- linux-3.12.24-rt37.orig/arch/xtensa/mm/fault.c
+++ linux-3.12.24-rt37/arch/xtensa/mm/fault.c
@@ -57,7 +57,7 @@ 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-3.12.24-rt37/block/blk-core.c
===================================================================
--- linux-3.12.24-rt37.orig/block/blk-core.c
+++ linux-3.12.24-rt37/block/blk-core.c
@@ -232,7 +232,7 @@ 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);
@@ -2925,7 +2925,7 @@ 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)
@@ -2973,7 +2973,6 @@ 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;
@@ -2991,11 +2990,6 @@ 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);
@@ -3008,7 +3002,7 @@ 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);
                }
 
                /*
@@ -3035,8 +3029,6 @@ 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-3.12.24-rt37/block/blk-ioc.c
===================================================================
--- linux-3.12.24-rt37.orig/block/blk-ioc.c
+++ linux-3.12.24-rt37/block/blk-ioc.c
@@ -8,6 +8,7 @@
 #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"
 
@@ -110,7 +111,7 @@ 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);
                }
        }
@@ -188,7 +189,7 @@ retry:
                        spin_unlock(icq->q->queue_lock);
                } else {
                        spin_unlock_irqrestore(&ioc->lock, flags);
-                       cpu_relax();
+                       cpu_chill();
                        goto retry;
                }
        }
Index: linux-3.12.24-rt37/block/blk-iopoll.c
===================================================================
--- linux-3.12.24-rt37.orig/block/blk-iopoll.c
+++ linux-3.12.24-rt37/block/blk-iopoll.c
@@ -38,6 +38,7 @@ 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);
 
@@ -135,6 +136,7 @@ static void blk_iopoll_softirq(struct so
                __raise_softirq_irqoff(BLOCK_IOPOLL_SOFTIRQ);
 
        local_irq_enable();
+       preempt_check_resched_rt();
 }
 
 /**
@@ -204,6 +206,7 @@ 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-3.12.24-rt37/block/blk-softirq.c
===================================================================
--- linux-3.12.24-rt37.orig/block/blk-softirq.c
+++ linux-3.12.24-rt37/block/blk-softirq.c
@@ -51,6 +51,7 @@ static void trigger_softirq(void *data)
                raise_softirq_irqoff(BLOCK_SOFTIRQ);
 
        local_irq_restore(flags);
+       preempt_check_resched_rt();
 }
 
 /*
@@ -93,6 +94,7 @@ 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;
@@ -150,6 +152,7 @@ do_local:
                goto do_local;
 
        local_irq_restore(flags);
+       preempt_check_resched_rt();
 }
 
 /**
Index: linux-3.12.24-rt37/crypto/algapi.c
===================================================================
--- linux-3.12.24-rt37.orig/crypto/algapi.c
+++ linux-3.12.24-rt37/crypto/algapi.c
@@ -684,13 +684,13 @@ 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-3.12.24-rt37/crypto/api.c
===================================================================
--- linux-3.12.24-rt37.orig/crypto/api.c
+++ linux-3.12.24-rt37/crypto/api.c
@@ -31,7 +31,7 @@ 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);
@@ -236,10 +236,10 @@ 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-3.12.24-rt37/crypto/internal.h
===================================================================
--- linux-3.12.24-rt37.orig/crypto/internal.h
+++ linux-3.12.24-rt37/crypto/internal.h
@@ -48,7 +48,7 @@ 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);
@@ -142,7 +142,7 @@ 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-3.12.24-rt37/drivers/acpi/acpica/acglobal.h
===================================================================
--- linux-3.12.24-rt37.orig/drivers/acpi/acpica/acglobal.h
+++ linux-3.12.24-rt37/drivers/acpi/acpica/acglobal.h
@@ -235,7 +235,7 @@ 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-3.12.24-rt37/drivers/acpi/acpica/hwregs.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/acpi/acpica/hwregs.c
+++ linux-3.12.24-rt37/drivers/acpi/acpica/hwregs.c
@@ -269,14 +269,14 @@ 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-3.12.24-rt37/drivers/acpi/acpica/hwxface.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/acpi/acpica/hwxface.c
+++ linux-3.12.24-rt37/drivers/acpi/acpica/hwxface.c
@@ -365,7 +365,7 @@ 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
@@ -426,7 +426,7 @@ 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-3.12.24-rt37/drivers/acpi/acpica/utmutex.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/acpi/acpica/utmutex.c
+++ linux-3.12.24-rt37/drivers/acpi/acpica/utmutex.c
@@ -88,7 +88,7 @@ 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);
        }
@@ -141,7 +141,7 @@ 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-3.12.24-rt37/drivers/ata/libata-sff.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/ata/libata-sff.c
+++ linux-3.12.24-rt37/drivers/ata/libata-sff.c
@@ -678,9 +678,9 @@ 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;
 }
@@ -719,7 +719,7 @@ 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 */
@@ -727,7 +727,7 @@ 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,
@@ -864,7 +864,7 @@ 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 */
@@ -872,7 +872,7 @@ 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-3.12.24-rt37/drivers/char/random.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/char/random.c
+++ linux-3.12.24-rt37/drivers/char/random.c
@@ -673,9 +673,12 @@ 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;
@@ -716,8 +719,6 @@ 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,
@@ -738,18 +739,16 @@ 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;
        }
@@ -763,7 +762,11 @@ 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-3.12.24-rt37/drivers/clocksource/tcb_clksrc.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/clocksource/tcb_clksrc.c
+++ linux-3.12.24-rt37/drivers/clocksource/tcb_clksrc.c
@@ -23,8 +23,7 @@
  *     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
@@ -74,6 +73,7 @@ static struct clocksource clksrc = {
 struct tc_clkevt_device {
        struct clock_event_device       clkevt;
        struct clk                      *clk;
+       u32                             freq;
        void __iomem                    *regs;
 };
 
@@ -82,13 +82,6 @@ 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)
@@ -111,11 +104,12 @@ 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));
@@ -128,7 +122,7 @@ 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));
@@ -157,8 +151,12 @@ 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,
        },
@@ -184,8 +182,9 @@ 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];
 
@@ -193,11 +192,15 @@ 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);
 }
@@ -322,8 +325,11 @@ 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-3.12.24-rt37/drivers/gpu/drm/drm_irq.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/gpu/drm/drm_irq.c
+++ linux-3.12.24-rt37/drivers/gpu/drm/drm_irq.c
@@ -628,11 +628,6 @@ 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();
 
@@ -644,8 +639,6 @@ 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-3.12.24-rt37/drivers/gpu/drm/i915/i915_gem.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/gpu/drm/i915/i915_gem.c
+++ linux-3.12.24-rt37/drivers/gpu/drm/i915/i915_gem.c
@@ -4792,7 +4792,7 @@ 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-3.12.24-rt37/drivers/gpu/drm/i915/i915_gem_execbuffer.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+++ linux-3.12.24-rt37/drivers/gpu/drm/i915/i915_gem_execbuffer.c
@@ -1129,7 +1129,9 @@ 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-3.12.24-rt37/drivers/i2c/busses/i2c-omap.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/i2c/busses/i2c-omap.c
+++ linux-3.12.24-rt37/drivers/i2c/busses/i2c-omap.c
@@ -879,15 +879,12 @@ 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-3.12.24-rt37/drivers/ide/alim15x3.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/ide/alim15x3.c
+++ linux-3.12.24-rt37/drivers/ide/alim15x3.c
@@ -234,7 +234,7 @@ 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) {
                /*
@@ -325,7 +325,7 @@ out:
        }
        pci_dev_put(north);
        pci_dev_put(isa_dev);
-       local_irq_restore(flags);
+       local_irq_restore_nort(flags);
        return 0;
 }
 
Index: linux-3.12.24-rt37/drivers/ide/hpt366.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/ide/hpt366.c
+++ linux-3.12.24-rt37/drivers/ide/hpt366.c
@@ -1241,7 +1241,7 @@ 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);
@@ -1252,7 +1252,7 @@ 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-3.12.24-rt37/drivers/ide/ide-io-std.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/ide/ide-io-std.c
+++ linux-3.12.24-rt37/drivers/ide/ide-io-std.c
@@ -175,7 +175,7 @@ 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);
                }
 
@@ -186,7 +186,7 @@ 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;
@@ -219,7 +219,7 @@ 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);
                }
 
@@ -230,7 +230,7 @@ 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-3.12.24-rt37/drivers/ide/ide-io.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/ide/ide-io.c
+++ linux-3.12.24-rt37/drivers/ide/ide-io.c
@@ -659,7 +659,7 @@ 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-3.12.24-rt37/drivers/ide/ide-iops.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/ide/ide-iops.c
+++ linux-3.12.24-rt37/drivers/ide/ide-iops.c
@@ -129,12 +129,12 @@ 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-3.12.24-rt37/drivers/ide/ide-probe.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/ide/ide-probe.c
+++ linux-3.12.24-rt37/drivers/ide/ide-probe.c
@@ -196,10 +196,10 @@ 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-3.12.24-rt37/drivers/ide/ide-taskfile.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/ide/ide-taskfile.c
+++ linux-3.12.24-rt37/drivers/ide/ide-taskfile.c
@@ -250,7 +250,7 @@ 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;
 
@@ -271,7 +271,7 @@ 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;
        }
@@ -414,7 +414,7 @@ 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-3.12.24-rt37/drivers/infiniband/ulp/ipoib/ipoib_multicast.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/infiniband/ulp/ipoib/ipoib_multicast.c
+++ linux-3.12.24-rt37/drivers/infiniband/ulp/ipoib/ipoib_multicast.c
@@ -783,7 +783,7 @@ 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);
 
@@ -865,7 +865,7 @@ 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-3.12.24-rt37/drivers/input/gameport/gameport.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/input/gameport/gameport.c
+++ linux-3.12.24-rt37/drivers/input/gameport/gameport.c
@@ -87,12 +87,12 @@ 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;
        }
@@ -111,11 +111,11 @@ 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-3.12.24-rt37/drivers/leds/trigger/Kconfig
===================================================================
--- linux-3.12.24-rt37.orig/drivers/leds/trigger/Kconfig
+++ linux-3.12.24-rt37/drivers/leds/trigger/Kconfig
@@ -61,7 +61,7 @@ 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-3.12.24-rt37/drivers/md/bcache/Kconfig
===================================================================
--- linux-3.12.24-rt37.orig/drivers/md/bcache/Kconfig
+++ linux-3.12.24-rt37/drivers/md/bcache/Kconfig
@@ -1,6 +1,7 @@
 
 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-3.12.24-rt37/drivers/md/dm.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/md/dm.c
+++ linux-3.12.24-rt37/drivers/md/dm.c
@@ -1813,14 +1813,14 @@ 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-3.12.24-rt37/drivers/md/raid5.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/md/raid5.c
+++ linux-3.12.24-rt37/drivers/md/raid5.c
@@ -1541,8 +1541,9 @@ 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++;
@@ -1594,7 +1595,8 @@ 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)
@@ -5456,6 +5458,7 @@ 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-3.12.24-rt37/drivers/md/raid5.h
===================================================================
--- linux-3.12.24-rt37.orig/drivers/md/raid5.h
+++ linux-3.12.24-rt37/drivers/md/raid5.h
@@ -444,6 +444,7 @@ 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-3.12.24-rt37/drivers/misc/Kconfig
===================================================================
--- linux-3.12.24-rt37.orig/drivers/misc/Kconfig
+++ linux-3.12.24-rt37/drivers/misc/Kconfig
@@ -63,6 +63,7 @@ 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
@@ -78,8 +79,7 @@ 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
@@ -93,6 +93,15 @@ 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
@@ -122,6 +131,35 @@ 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-3.12.24-rt37/drivers/misc/Makefile
===================================================================
--- linux-3.12.24-rt37.orig/drivers/misc/Makefile
+++ linux-3.12.24-rt37/drivers/misc/Makefile
@@ -53,3 +53,4 @@ 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-3.12.24-rt37/drivers/misc/hwlat_detector.c
===================================================================
--- /dev/null
+++ linux-3.12.24-rt37/drivers/misc/hwlat_detector.c
@@ -0,0 +1,1240 @@
+/*
+ * 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-3.12.24-rt37/drivers/mmc/host/mmci.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/mmc/host/mmci.c
+++ linux-3.12.24-rt37/drivers/mmc/host/mmci.c
@@ -1023,15 +1023,12 @@ 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;
@@ -1071,8 +1068,6 @@ 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-3.12.24-rt37/drivers/net/Kconfig
===================================================================
--- linux-3.12.24-rt37.orig/drivers/net/Kconfig
+++ linux-3.12.24-rt37/drivers/net/Kconfig
@@ -160,6 +160,7 @@ 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-3.12.24-rt37/drivers/net/ethernet/3com/3c59x.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/net/ethernet/3com/3c59x.c
+++ linux-3.12.24-rt37/drivers/net/ethernet/3com/3c59x.c
@@ -842,9 +842,9 @@ 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
 
@@ -1917,12 +1917,12 @@ 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-3.12.24-rt37/drivers/net/ethernet/atheros/atl1c/atl1c_main.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/net/ethernet/atheros/atl1c/atl1c_main.c
+++ linux-3.12.24-rt37/drivers/net/ethernet/atheros/atl1c/atl1c_main.c
@@ -2206,11 +2206,7 @@ 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-3.12.24-rt37/drivers/net/ethernet/atheros/atl1e/atl1e_main.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/net/ethernet/atheros/atl1e/atl1e_main.c
+++ linux-3.12.24-rt37/drivers/net/ethernet/atheros/atl1e/atl1e_main.c
@@ -1838,8 +1838,7 @@ 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-3.12.24-rt37/drivers/net/ethernet/chelsio/cxgb/sge.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/net/ethernet/chelsio/cxgb/sge.c
+++ linux-3.12.24-rt37/drivers/net/ethernet/chelsio/cxgb/sge.c
@@ -1665,8 +1665,7 @@ 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-3.12.24-rt37/drivers/net/ethernet/freescale/gianfar.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/net/ethernet/freescale/gianfar.c
+++ linux-3.12.24-rt37/drivers/net/ethernet/freescale/gianfar.c
@@ -134,7 +134,6 @@ 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);
@@ -1301,7 +1300,7 @@ 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);
 
@@ -1319,7 +1318,7 @@ 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);
 
@@ -1361,7 +1360,7 @@ 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);
 
@@ -1373,7 +1372,7 @@ 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);
 
@@ -1701,7 +1700,7 @@ 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);
 
@@ -1709,7 +1708,7 @@ 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) {
@@ -2387,7 +2386,7 @@ 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) {
@@ -2420,7 +2419,7 @@ 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)
@@ -2516,7 +2515,7 @@ 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;
@@ -2616,6 +2615,7 @@ 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)
@@ -2939,10 +2939,14 @@ 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 */
@@ -3101,7 +3105,7 @@ 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) {
@@ -3175,7 +3179,7 @@ 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
@@ -3381,14 +3385,14 @@ 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(&regs->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-3.12.24-rt37/drivers/net/ethernet/freescale/gianfar_ethtool.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/net/ethernet/freescale/gianfar_ethtool.c
+++ linux-3.12.24-rt37/drivers/net/ethernet/freescale/gianfar_ethtool.c
@@ -501,7 +501,7 @@ 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);
 
@@ -509,7 +509,7 @@ 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],
@@ -624,7 +624,7 @@ 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);
 
@@ -632,7 +632,7 @@ 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-3.12.24-rt37/drivers/net/ethernet/freescale/gianfar_sysfs.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/net/ethernet/freescale/gianfar_sysfs.c
+++ linux-3.12.24-rt37/drivers/net/ethernet/freescale/gianfar_sysfs.c
@@ -68,7 +68,7 @@ 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 */
@@ -84,7 +84,7 @@ static ssize_t gfar_set_bd_stash(struct
        gfar_write(&regs->attr, temp);
 
        unlock_rx_qs(priv);
-       local_irq_restore(flags);
+       local_irq_restore_nort(flags);
 
        return count;
 }
@@ -112,7 +112,7 @@ 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)
@@ -140,7 +140,7 @@ 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;
 }
@@ -171,7 +171,7 @@ 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)
@@ -189,7 +189,7 @@ 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;
 }
@@ -219,7 +219,7 @@ 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;
@@ -230,7 +230,7 @@ static ssize_t gfar_set_fifo_threshold(s
        gfar_write(&regs->fifo_tx_thr, temp);
 
        unlock_tx_qs(priv);
-       local_irq_restore(flags);
+       local_irq_restore_nort(flags);
 
        return count;
 }
@@ -259,7 +259,7 @@ 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;
@@ -270,7 +270,7 @@ static ssize_t gfar_set_fifo_starve(stru
        gfar_write(&regs->fifo_tx_starve, temp);
 
        unlock_tx_qs(priv);
-       local_irq_restore(flags);
+       local_irq_restore_nort(flags);
 
        return count;
 }
@@ -300,7 +300,7 @@ 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;
@@ -311,7 +311,7 @@ static ssize_t gfar_set_fifo_starve_off(
        gfar_write(&regs->fifo_tx_starve_shutoff, temp);
 
        unlock_tx_qs(priv);
-       local_irq_restore(flags);
+       local_irq_restore_nort(flags);
 
        return count;
 }
Index: linux-3.12.24-rt37/drivers/net/ethernet/neterion/s2io.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/net/ethernet/neterion/s2io.c
+++ linux-3.12.24-rt37/drivers/net/ethernet/neterion/s2io.c
@@ -4089,12 +4089,7 @@ 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-3.12.24-rt37/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c
+++ linux-3.12.24-rt37/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c
@@ -2148,10 +2148,8 @@ 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-3.12.24-rt37/drivers/net/ethernet/realtek/8139too.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/net/ethernet/realtek/8139too.c
+++ linux-3.12.24-rt37/drivers/net/ethernet/realtek/8139too.c
@@ -2213,7 +2213,7 @@ 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-3.12.24-rt37/drivers/net/ethernet/tehuti/tehuti.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/net/ethernet/tehuti/tehuti.c
+++ linux-3.12.24-rt37/drivers/net/ethernet/tehuti/tehuti.c
@@ -1629,13 +1629,8 @@ 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-3.12.24-rt37/drivers/net/rionet.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/net/rionet.c
+++ linux-3.12.24-rt37/drivers/net/rionet.c
@@ -174,11 +174,7 @@ 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-3.12.24-rt37/drivers/net/wireless/iwlwifi/pcie/trans.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/net/wireless/iwlwifi/pcie/trans.c
+++ linux-3.12.24-rt37/drivers/net/wireless/iwlwifi/pcie/trans.c
@@ -1394,6 +1394,20 @@ 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)
@@ -1512,9 +1526,14 @@ 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-3.12.24-rt37/drivers/net/wireless/orinoco/orinoco_usb.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/net/wireless/orinoco/orinoco_usb.c
+++ linux-3.12.24-rt37/drivers/net/wireless/orinoco/orinoco_usb.c
@@ -714,7 +714,7 @@ 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-3.12.24-rt37/drivers/pci/access.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/pci/access.c
+++ linux-3.12.24-rt37/drivers/pci/access.c
@@ -465,7 +465,7 @@ 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-3.12.24-rt37/drivers/scsi/fcoe/fcoe.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/scsi/fcoe/fcoe.c
+++ linux-3.12.24-rt37/drivers/scsi/fcoe/fcoe.c
@@ -1285,7 +1285,7 @@ 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);
@@ -1341,7 +1341,7 @@ 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
@@ -1559,11 +1559,11 @@ 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;
 }
@@ -1761,11 +1761,11 @@ 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;
 }
 
@@ -1841,13 +1841,13 @@ 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-3.12.24-rt37/drivers/scsi/fcoe/fcoe_ctlr.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/scsi/fcoe/fcoe_ctlr.c
+++ linux-3.12.24-rt37/drivers/scsi/fcoe/fcoe_ctlr.c
@@ -792,7 +792,7 @@ 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;
@@ -828,7 +828,7 @@ 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-3.12.24-rt37/drivers/scsi/libfc/fc_exch.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/scsi/libfc/fc_exch.c
+++ linux-3.12.24-rt37/drivers/scsi/libfc/fc_exch.c
@@ -741,10 +741,10 @@ 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-3.12.24-rt37/drivers/scsi/qla2xxx/qla_inline.h
===================================================================
--- linux-3.12.24-rt37.orig/drivers/scsi/qla2xxx/qla_inline.h
+++ linux-3.12.24-rt37/drivers/scsi/qla2xxx/qla_inline.h
@@ -58,12 +58,12 @@ 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-3.12.24-rt37/drivers/tty/serial/8250/8250_core.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/tty/serial/8250/8250_core.c
+++ linux-3.12.24-rt37/drivers/tty/serial/8250/8250_core.c
@@ -38,6 +38,7 @@
 #include <linux/nmi.h>
 #include <linux/mutex.h>
 #include <linux/slab.h>
+#include <linux/kdb.h>
 #ifdef CONFIG_SPARC
 #include <linux/sunserialcore.h>
 #endif
@@ -80,7 +81,16 @@ 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)
 
@@ -2864,14 +2874,10 @@ 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
@@ -2903,8 +2909,7 @@ 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-3.12.24-rt37/drivers/tty/serial/amba-pl011.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/tty/serial/amba-pl011.c
+++ linux-3.12.24-rt37/drivers/tty/serial/amba-pl011.c
@@ -1916,13 +1916,19 @@ 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
@@ -1944,8 +1950,7 @@ 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-3.12.24-rt37/drivers/tty/serial/omap-serial.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/tty/serial/omap-serial.c
+++ linux-3.12.24-rt37/drivers/tty/serial/omap-serial.c
@@ -1232,13 +1232,10 @@ 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
@@ -1267,8 +1264,7 @@ 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-3.12.24-rt37/drivers/tty/serial/sunhv.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/tty/serial/sunhv.c
+++ linux-3.12.24-rt37/drivers/tty/serial/sunhv.c
@@ -433,13 +433,10 @@ 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);
@@ -470,8 +467,7 @@ 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)
@@ -492,7 +488,10 @@ 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) {
@@ -507,8 +506,7 @@ 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-3.12.24-rt37/drivers/tty/serial/sunsab.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/tty/serial/sunsab.c
+++ linux-3.12.24-rt37/drivers/tty/serial/sunsab.c
@@ -844,20 +844,16 @@ 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-3.12.24-rt37/drivers/tty/serial/sunsu.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/tty/serial/sunsu.c
+++ linux-3.12.24-rt37/drivers/tty/serial/sunsu.c
@@ -1295,13 +1295,10 @@ 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
@@ -1319,8 +1316,7 @@ 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-3.12.24-rt37/drivers/tty/serial/sunzilog.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/tty/serial/sunzilog.c
+++ linux-3.12.24-rt37/drivers/tty/serial/sunzilog.c
@@ -1195,20 +1195,16 @@ 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-3.12.24-rt37/drivers/usb/core/hcd.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/usb/core/hcd.c
+++ linux-3.12.24-rt37/drivers/usb/core/hcd.c
@@ -1677,9 +1677,9 @@ 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)))
@@ -2331,7 +2331,7 @@ 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;
@@ -2340,7 +2340,7 @@ 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-3.12.24-rt37/drivers/usb/gadget/f_fs.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/usb/gadget/f_fs.c
+++ linux-3.12.24-rt37/drivers/usb/gadget/f_fs.c
@@ -1282,7 +1282,7 @@ 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-3.12.24-rt37/drivers/usb/gadget/inode.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/usb/gadget/inode.c
+++ linux-3.12.24-rt37/drivers/usb/gadget/inode.c
@@ -340,7 +340,7 @@ 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)) {
@@ -349,7 +349,7 @@ 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-3.12.24-rt37/drivers/usb/host/ohci-hcd.c
===================================================================
--- linux-3.12.24-rt37.orig/drivers/usb/host/ohci-hcd.c
+++ linux-3.12.24-rt37/drivers/usb/host/ohci-hcd.c
@@ -874,9 +874,13 @@ 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-3.12.24-rt37/fs/autofs4/autofs_i.h
===================================================================
--- linux-3.12.24-rt37.orig/fs/autofs4/autofs_i.h
+++ linux-3.12.24-rt37/fs/autofs4/autofs_i.h
@@ -34,6 +34,7 @@
 #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-3.12.24-rt37/fs/autofs4/expire.c
===================================================================
--- linux-3.12.24-rt37.orig/fs/autofs4/expire.c
+++ linux-3.12.24-rt37/fs/autofs4/expire.c
@@ -157,7 +157,7 @@ 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-3.12.24-rt37/fs/buffer.c
===================================================================
--- linux-3.12.24-rt37.orig/fs/buffer.c
+++ linux-3.12.24-rt37/fs/buffer.c
@@ -322,8 +322,7 @@ 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;
@@ -336,8 +335,7 @@ 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
@@ -349,9 +347,7 @@ 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);
 }
 
 /*
@@ -385,8 +381,7 @@ 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);
@@ -398,15 +393,12 @@ 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);
 
@@ -3336,6 +3328,7 @@ 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-3.12.24-rt37/fs/dcache.c
===================================================================
--- linux-3.12.24-rt37.orig/fs/dcache.c
+++ linux-3.12.24-rt37/fs/dcache.c
@@ -19,6 +19,7 @@
 #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>
@@ -554,7 +555,7 @@ 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 */
        }
@@ -2391,7 +2392,7 @@ 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-3.12.24-rt37/fs/eventpoll.c
===================================================================
--- linux-3.12.24-rt37.orig/fs/eventpoll.c
+++ linux-3.12.24-rt37/fs/eventpoll.c
@@ -505,12 +505,12 @@ 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-3.12.24-rt37/fs/exec.c
===================================================================
--- linux-3.12.24-rt37.orig/fs/exec.c
+++ linux-3.12.24-rt37/fs/exec.c
@@ -840,10 +840,12 @@ 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);
+       preempt_enable_rt();
        task_unlock(tsk);
        arch_pick_mmap_layout(mm);
        if (old_mm) {
Index: linux-3.12.24-rt37/fs/jbd/checkpoint.c
===================================================================
--- linux-3.12.24-rt37.orig/fs/jbd/checkpoint.c
+++ linux-3.12.24-rt37/fs/jbd/checkpoint.c
@@ -129,6 +129,8 @@ 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-3.12.24-rt37/fs/jbd2/checkpoint.c
===================================================================
--- linux-3.12.24-rt37.orig/fs/jbd2/checkpoint.c
+++ linux-3.12.24-rt37/fs/jbd2/checkpoint.c
@@ -125,6 +125,8 @@ 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-3.12.24-rt37/fs/namespace.c
===================================================================
--- linux-3.12.24-rt37.orig/fs/namespace.c
+++ linux-3.12.24-rt37/fs/namespace.c
@@ -23,6 +23,7 @@
 #include <linux/uaccess.h>
 #include <linux/proc_ns.h>
 #include <linux/magic.h>
+#include <linux/delay.h>
 #include "pnode.h"
 #include "internal.h"
 
@@ -315,8 +316,11 @@ 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-3.12.24-rt37/fs/ntfs/aops.c
===================================================================
--- linux-3.12.24-rt37.orig/fs/ntfs/aops.c
+++ linux-3.12.24-rt37/fs/ntfs/aops.c
@@ -108,8 +108,7 @@ 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;
@@ -124,8 +123,7 @@ 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
@@ -146,13 +144,13 @@ 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);
@@ -160,9 +158,7 @@ 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-3.12.24-rt37/fs/timerfd.c
===================================================================
--- linux-3.12.24-rt37.orig/fs/timerfd.c
+++ linux-3.12.24-rt37/fs/timerfd.c
@@ -380,7 +380,10 @@ 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-3.12.24-rt37/include/acpi/platform/aclinux.h
===================================================================
--- linux-3.12.24-rt37.orig/include/acpi/platform/aclinux.h
+++ linux-3.12.24-rt37/include/acpi/platform/aclinux.h
@@ -72,6 +72,7 @@
 
 #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__ */
@@ -174,6 +175,19 @@ 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-3.12.24-rt37/include/asm-generic/bug.h
===================================================================
--- linux-3.12.24-rt37.orig/include/asm-generic/bug.h
+++ linux-3.12.24-rt37/include/asm-generic/bug.h
@@ -202,6 +202,20 @@ 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-3.12.24-rt37/include/linux/buffer_head.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/buffer_head.h
+++ linux-3.12.24-rt37/include/linux/buffer_head.h
@@ -75,8 +75,52 @@ 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-3.12.24-rt37/include/linux/completion.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/completion.h
+++ linux-3.12.24-rt37/include/linux/completion.h
@@ -8,7 +8,7 @@
  * 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"
@@ -24,11 +24,11 @@
  */
 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; })
@@ -73,7 +73,7 @@ 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-3.12.24-rt37/include/linux/cpu.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/cpu.h
+++ linux-3.12.24-rt37/include/linux/cpu.h
@@ -179,6 +179,8 @@ 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)
@@ -206,6 +208,8 @@ 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-3.12.24-rt37/include/linux/delay.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/delay.h
+++ linux-3.12.24-rt37/include/linux/delay.h
@@ -52,4 +52,10 @@ 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-3.12.24-rt37/include/linux/ftrace_event.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/ftrace_event.h
+++ linux-3.12.24-rt37/include/linux/ftrace_event.h
@@ -56,6 +56,9 @@ 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-3.12.24-rt37/include/linux/highmem.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/highmem.h
+++ linux-3.12.24-rt37/include/linux/highmem.h
@@ -7,6 +7,7 @@
 #include <linux/mm.h>
 #include <linux/uaccess.h>
 #include <linux/hardirq.h>
+#include <linux/sched.h>
 
 #include <asm/cacheflush.h>
 
@@ -85,32 +86,51 @@ 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-3.12.24-rt37/include/linux/hrtimer.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/hrtimer.h
+++ linux-3.12.24-rt37/include/linux/hrtimer.h
@@ -111,6 +111,11 @@ 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;
@@ -147,6 +152,7 @@ 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;
@@ -190,6 +196,9 @@ 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];
 };
 
@@ -385,6 +394,13 @@ 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);
@@ -445,9 +461,8 @@ 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-3.12.24-rt37/include/linux/idr.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/idr.h
+++ linux-3.12.24-rt37/include/linux/idr.h
@@ -92,10 +92,14 @@ 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-3.12.24-rt37/include/linux/init_task.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/init_task.h
+++ linux-3.12.24-rt37/include/linux/init_task.h
@@ -144,9 +144,16 @@ 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
@@ -208,6 +215,7 @@ 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-3.12.24-rt37/include/linux/interrupt.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/interrupt.h
+++ linux-3.12.24-rt37/include/linux/interrupt.h
@@ -58,6 +58,7 @@
  * 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
@@ -71,6 +72,7 @@
 #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)
 
@@ -176,7 +178,7 @@ 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);
@@ -253,6 +255,7 @@ 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);
 };
@@ -352,9 +355,13 @@ 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
@@ -410,8 +417,14 @@ 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);
@@ -419,6 +432,8 @@ 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
@@ -459,8 +474,9 @@ 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.
@@ -485,27 +501,36 @@ 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
@@ -554,17 +579,8 @@ 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);
@@ -596,6 +612,12 @@ 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-3.12.24-rt37/include/linux/irq.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/irq.h
+++ linux-3.12.24-rt37/include/linux/irq.h
@@ -70,6 +70,7 @@ 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,
@@ -94,12 +95,14 @@ 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-3.12.24-rt37/include/linux/irq_work.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/irq_work.h
+++ linux-3.12.24-rt37/include/linux/irq_work.h
@@ -16,6 +16,7 @@
 #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-3.12.24-rt37/include/linux/irqdesc.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/irqdesc.h
+++ linux-3.12.24-rt37/include/linux/irqdesc.h
@@ -56,6 +56,7 @@ 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-3.12.24-rt37/include/linux/irqflags.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/irqflags.h
+++ linux-3.12.24-rt37/include/linux/irqflags.h
@@ -25,8 +25,6 @@
 # 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)
@@ -39,9 +37,15 @@
 # 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) || \
@@ -147,4 +151,23 @@
 
 #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-3.12.24-rt37/include/linux/jbd_common.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/jbd_common.h
+++ linux-3.12.24-rt37/include/linux/jbd_common.h
@@ -15,32 +15,56 @@ 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-3.12.24-rt37/include/linux/jump_label.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/jump_label.h
+++ linux-3.12.24-rt37/include/linux/jump_label.h
@@ -49,7 +49,8 @@
 #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-3.12.24-rt37/include/linux/kdb.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/kdb.h
+++ linux-3.12.24-rt37/include/linux/kdb.h
@@ -115,7 +115,7 @@ 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 */
@@ -150,6 +150,7 @@ 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-3.12.24-rt37/include/linux/kernel.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/kernel.h
+++ linux-3.12.24-rt37/include/linux/kernel.h
@@ -412,6 +412,7 @@ extern enum system_states {
        SYSTEM_HALT,
        SYSTEM_POWER_OFF,
        SYSTEM_RESTART,
+       SYSTEM_SUSPEND,
 } system_state;
 
 #define TAINT_PROPRIETARY_MODULE       0
Index: linux-3.12.24-rt37/include/linux/lglock.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/lglock.h
+++ linux-3.12.24-rt37/include/linux/lglock.h
@@ -42,22 +42,37 @@
 #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-3.12.24-rt37/include/linux/list.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/list.h
+++ linux-3.12.24-rt37/include/linux/list.h
@@ -373,6 +373,17 @@ 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-3.12.24-rt37/include/linux/list_bl.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/list_bl.h
+++ linux-3.12.24-rt37/include/linux/list_bl.h
@@ -2,6 +2,7 @@
 #define _LINUX_LIST_BL_H
 
 #include <linux/list.h>
+#include <linux/spinlock.h>
 #include <linux/bit_spinlock.h>
 
 /*
@@ -32,13 +33,22 @@
 
 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)
 {
@@ -117,12 +127,26 @@ 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-3.12.24-rt37/include/linux/locallock.h
===================================================================
--- /dev/null
+++ linux-3.12.24-rt37/include/linux/locallock.h
@@ -0,0 +1,270 @@
+#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-3.12.24-rt37/include/linux/mm.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/mm.h
+++ linux-3.12.24-rt37/include/linux/mm.h
@@ -1252,27 +1252,59 @@ 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-3.12.24-rt37/include/linux/mm_types.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/mm_types.h
+++ linux-3.12.24-rt37/include/linux/mm_types.h
@@ -11,6 +11,7 @@
 #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>
@@ -142,7 +143,11 @@ 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 */
@@ -444,6 +449,9 @@ 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-3.12.24-rt37/include/linux/mutex.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/mutex.h
+++ linux-3.12.24-rt37/include/linux/mutex.h
@@ -18,6 +18,17 @@
 #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:
  *
@@ -99,13 +110,6 @@ 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) \
@@ -173,6 +177,8 @@ 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-3.12.24-rt37/include/linux/mutex_rt.h
===================================================================
--- /dev/null
+++ linux-3.12.24-rt37/include/linux/mutex_rt.h
@@ -0,0 +1,84 @@
+#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-3.12.24-rt37/include/linux/netdevice.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/netdevice.h
+++ linux-3.12.24-rt37/include/linux/netdevice.h
@@ -1214,7 +1214,7 @@ 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
@@ -1930,6 +1930,7 @@ 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-3.12.24-rt37/include/linux/netfilter/x_tables.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/netfilter/x_tables.h
+++ linux-3.12.24-rt37/include/linux/netfilter/x_tables.h
@@ -3,6 +3,7 @@
 
 
 #include <linux/netdevice.h>
+#include <linux/locallock.h>
 #include <uapi/linux/netfilter/x_tables.h>
 
 /**
@@ -284,6 +285,8 @@ 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
  *
@@ -298,6 +301,9 @@ 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().
@@ -328,6 +334,7 @@ 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-3.12.24-rt37/include/linux/notifier.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/notifier.h
+++ linux-3.12.24-rt37/include/linux/notifier.h
@@ -6,7 +6,7 @@
  *
  *                             Alan Cox <Alan.Cox@linux.org>
  */
- 
+
 #ifndef _LINUX_NOTIFIER_H
 #define _LINUX_NOTIFIER_H
 #include <linux/errno.h>
@@ -42,9 +42,7 @@
  * 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,
@@ -88,7 +86,7 @@ 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);
@@ -101,7 +99,13 @@ 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 =                      \
@@ -113,6 +117,18 @@ 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,
@@ -182,12 +198,12 @@ 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-3.12.24-rt37/include/linux/page_cgroup.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/page_cgroup.h
+++ linux-3.12.24-rt37/include/linux/page_cgroup.h
@@ -24,6 +24,9 @@ enum {
  */
 struct page_cgroup {
        unsigned long flags;
+#ifdef CONFIG_PREEMPT_RT_BASE
+       spinlock_t pcg_lock;
+#endif
        struct mem_cgroup *mem_cgroup;
 };
 
@@ -74,12 +77,20 @@ 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 */
@@ -102,6 +113,10 @@ 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-3.12.24-rt37/include/linux/percpu.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/percpu.h
+++ linux-3.12.24-rt37/include/linux/percpu.h
@@ -48,6 +48,31 @@
        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-3.12.24-rt37/include/linux/pid.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/pid.h
+++ linux-3.12.24-rt37/include/linux/pid.h
@@ -2,6 +2,7 @@
 #define _LINUX_PID_H
 
 #include <linux/rcupdate.h>
+#include <linux/atomic.h>
 
 enum pid_type
 {
Index: linux-3.12.24-rt37/include/linux/preempt.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/preempt.h
+++ linux-3.12.24-rt37/include/linux/preempt.h
@@ -23,15 +23,38 @@
 
 #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
 
@@ -64,17 +87,36 @@ 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)
@@ -123,9 +165,31 @@ 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-3.12.24-rt37/include/linux/preempt_mask.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/preempt_mask.h
+++ linux-3.12.24-rt37/include/linux/preempt_mask.h
@@ -58,7 +58,11 @@
 #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
@@ -71,9 +75,15 @@
 #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?
@@ -84,7 +94,6 @@
 #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-3.12.24-rt37/include/linux/printk.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/printk.h
+++ linux-3.12.24-rt37/include/linux/printk.h
@@ -101,9 +101,11 @@ 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
@@ -137,7 +139,6 @@ 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-3.12.24-rt37/include/linux/radix-tree.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/radix-tree.h
+++ linux-3.12.24-rt37/include/linux/radix-tree.h
@@ -230,8 +230,13 @@ unsigned long radix_tree_next_hole(struc
                                unsigned long index, unsigned long max_scan);
 unsigned long radix_tree_prev_hole(struct radix_tree_root *root,
                                unsigned long index, unsigned long max_scan);
+#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);
@@ -256,7 +261,7 @@ unsigned long radix_tree_locate_item(str
 
 static inline void radix_tree_preload_end(void)
 {
-       preempt_enable();
+       preempt_enable_nort();
 }
 
 /**
Index: linux-3.12.24-rt37/include/linux/random.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/random.h
+++ linux-3.12.24-rt37/include/linux/random.h
@@ -12,7 +12,7 @@
 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-3.12.24-rt37/include/linux/rcupdate.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/rcupdate.h
+++ linux-3.12.24-rt37/include/linux/rcupdate.h
@@ -128,6 +128,9 @@ 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.
@@ -151,6 +154,7 @@ 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.
@@ -190,6 +194,11 @@ 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 */
 
@@ -213,6 +222,8 @@ 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 */
@@ -362,7 +373,14 @@ 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?
@@ -819,10 +837,14 @@ 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
 }
 
 /*
@@ -832,10 +854,14 @@ 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-3.12.24-rt37/include/linux/rcutree.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/rcutree.h
+++ linux-3.12.24-rt37/include/linux/rcutree.h
@@ -44,7 +44,11 @@ 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);
 
@@ -72,17 +76,19 @@ 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);
@@ -90,4 +96,12 @@ 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-3.12.24-rt37/include/linux/rtmutex.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/rtmutex.h
+++ linux-3.12.24-rt37/include/linux/rtmutex.h
@@ -14,10 +14,14 @@
 
 #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
  *
@@ -29,9 +33,10 @@ 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
@@ -56,19 +61,39 @@ 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)
@@ -90,6 +115,7 @@ 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-3.12.24-rt37/include/linux/rwlock_rt.h
===================================================================
--- /dev/null
+++ linux-3.12.24-rt37/include/linux/rwlock_rt.h
@@ -0,0 +1,99 @@
+#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-3.12.24-rt37/include/linux/rwlock_types.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/rwlock_types.h
+++ linux-3.12.24-rt37/include/linux/rwlock_types.h
@@ -1,6 +1,10 @@
 #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
@@ -43,6 +47,7 @@ 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-3.12.24-rt37/include/linux/rwlock_types_rt.h
===================================================================
--- /dev/null
+++ linux-3.12.24-rt37/include/linux/rwlock_types_rt.h
@@ -0,0 +1,33 @@
+#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-3.12.24-rt37/include/linux/rwsem.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/rwsem.h
+++ linux-3.12.24-rt37/include/linux/rwsem.h
@@ -16,6 +16,10 @@
 
 #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
@@ -149,4 +153,6 @@ 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-3.12.24-rt37/include/linux/rwsem_rt.h
===================================================================
--- /dev/null
+++ linux-3.12.24-rt37/include/linux/rwsem_rt.h
@@ -0,0 +1,128 @@
+#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-3.12.24-rt37/include/linux/sched.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/sched.h
+++ linux-3.12.24-rt37/include/linux/sched.h
@@ -23,6 +23,7 @@ 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>
@@ -52,6 +53,7 @@ struct sched_param {
 #include <linux/llist.h>
 #include <linux/uidgid.h>
 #include <linux/gfp.h>
+#include <linux/hardirq.h>
 
 #include <asm/processor.h>
 
@@ -165,11 +167,8 @@ 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)
@@ -1023,6 +1022,7 @@ 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 */
@@ -1065,6 +1065,12 @@ 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;
 
@@ -1161,7 +1167,8 @@ 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,
@@ -1177,6 +1184,9 @@ 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
@@ -1208,10 +1218,15 @@ 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;
@@ -1248,6 +1263,9 @@ 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;
@@ -1323,6 +1341,9 @@ 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;
@@ -1390,6 +1411,12 @@ 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 {
@@ -1413,11 +1440,19 @@ 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);
@@ -1430,6 +1465,17 @@ 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;
@@ -1583,6 +1629,15 @@ 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)
@@ -1590,6 +1645,7 @@ 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,
@@ -1628,6 +1684,7 @@ 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 */
@@ -1773,6 +1830,10 @@ 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)
@@ -1785,6 +1846,9 @@ 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
@@ -1992,6 +2056,7 @@ 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);
@@ -2106,12 +2171,24 @@ 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 */
@@ -2404,6 +2481,52 @@ 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);
@@ -2435,9 +2558,49 @@ 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;
 }
 
 /*
@@ -2456,7 +2619,7 @@ 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
@@ -2467,12 +2630,16 @@ 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)
 {
@@ -2658,6 +2825,26 @@ 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-3.12.24-rt37/include/linux/sched/rt.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/sched/rt.h
+++ linux-3.12.24-rt37/include/linux/sched/rt.h
@@ -35,6 +35,7 @@ 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)
 {
@@ -45,6 +46,10 @@ 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-3.12.24-rt37/include/linux/seqlock.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/seqlock.h
+++ linux-3.12.24-rt37/include/linux/seqlock.h
@@ -152,18 +152,30 @@ 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
@@ -204,10 +216,32 @@ 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)
 {
@@ -222,36 +256,36 @@ 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);
 }
 
@@ -260,7 +294,7 @@ 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;
 }
 
@@ -270,7 +304,7 @@ 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-3.12.24-rt37/include/linux/signal.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/signal.h
+++ linux-3.12.24-rt37/include/linux/signal.h
@@ -226,6 +226,7 @@ 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-3.12.24-rt37/include/linux/skbuff.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/skbuff.h
+++ linux-3.12.24-rt37/include/linux/skbuff.h
@@ -133,6 +133,7 @@ struct sk_buff_head {
 
        __u32           qlen;
        spinlock_t      lock;
+       raw_spinlock_t  raw_lock;
 };
 
 struct sk_buff;
@@ -1073,6 +1074,12 @@ 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-3.12.24-rt37/include/linux/smp.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/smp.h
+++ linux-3.12.24-rt37/include/linux/smp.h
@@ -188,6 +188,9 @@ 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-3.12.24-rt37/include/linux/spinlock.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/spinlock.h
+++ linux-3.12.24-rt37/include/linux/spinlock.h
@@ -262,7 +262,11 @@ 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:
@@ -273,6 +277,10 @@ 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
  */
@@ -402,4 +410,6 @@ 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-3.12.24-rt37/include/linux/spinlock_api_smp.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/spinlock_api_smp.h
+++ linux-3.12.24-rt37/include/linux/spinlock_api_smp.h
@@ -191,6 +191,8 @@ 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-3.12.24-rt37/include/linux/spinlock_rt.h
===================================================================
--- /dev/null
+++ linux-3.12.24-rt37/include/linux/spinlock_rt.h
@@ -0,0 +1,166 @@
+#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-3.12.24-rt37/include/linux/spinlock_types.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/spinlock_types.h
+++ linux-3.12.24-rt37/include/linux/spinlock_types.h
@@ -9,80 +9,15 @@
  * 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-3.12.24-rt37/include/linux/spinlock_types_nort.h
===================================================================
--- /dev/null
+++ linux-3.12.24-rt37/include/linux/spinlock_types_nort.h
@@ -0,0 +1,33 @@
+#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-3.12.24-rt37/include/linux/spinlock_types_raw.h
===================================================================
--- /dev/null
+++ linux-3.12.24-rt37/include/linux/spinlock_types_raw.h
@@ -0,0 +1,56 @@
+#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-3.12.24-rt37/include/linux/spinlock_types_rt.h
===================================================================
--- /dev/null
+++ linux-3.12.24-rt37/include/linux/spinlock_types_rt.h
@@ -0,0 +1,51 @@
+#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-3.12.24-rt37/include/linux/srcu.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/srcu.h
+++ linux-3.12.24-rt37/include/linux/srcu.h
@@ -84,10 +84,10 @@ 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),        \
@@ -104,11 +104,12 @@ 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-3.12.24-rt37/include/linux/sysctl.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/sysctl.h
+++ linux-3.12.24-rt37/include/linux/sysctl.h
@@ -25,6 +25,7 @@
 #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-3.12.24-rt37/include/linux/timer.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/timer.h
+++ linux-3.12.24-rt37/include/linux/timer.h
@@ -241,7 +241,7 @@ 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-3.12.24-rt37/include/linux/uaccess.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/uaccess.h
+++ linux-3.12.24-rt37/include/linux/uaccess.h
@@ -6,38 +6,37 @@
 
 /*
  * 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,
@@ -77,9 +76,9 @@ 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-3.12.24-rt37/include/linux/uprobes.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/uprobes.h
+++ linux-3.12.24-rt37/include/linux/uprobes.h
@@ -26,6 +26,7 @@
 
 #include <linux/errno.h>
 #include <linux/rbtree.h>
+#include <linux/wait.h>
 
 struct vm_area_struct;
 struct mm_struct;
Index: linux-3.12.24-rt37/include/linux/vmstat.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/vmstat.h
+++ linux-3.12.24-rt37/include/linux/vmstat.h
@@ -29,7 +29,9 @@ 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)
@@ -39,7 +41,9 @@ 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-3.12.24-rt37/include/linux/wait-simple.h
===================================================================
--- /dev/null
+++ linux-3.12.24-rt37/include/linux/wait-simple.h
@@ -0,0 +1,207 @@
+#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-3.12.24-rt37/include/linux/wait.h
===================================================================
--- linux-3.12.24-rt37.orig/include/linux/wait.h
+++ linux-3.12.24-rt37/include/linux/wait.h
@@ -7,6 +7,7 @@
 #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-3.12.24-rt37/include/net/dst.h
===================================================================
--- linux-3.12.24-rt37.orig/include/net/dst.h
+++ linux-3.12.24-rt37/include/net/dst.h
@@ -395,7 +395,7 @@ 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-3.12.24-rt37/include/net/neighbour.h
===================================================================
--- linux-3.12.24-rt37.orig/include/net/neighbour.h
+++ linux-3.12.24-rt37/include/net/neighbour.h
@@ -333,7 +333,7 @@ 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;
@@ -388,7 +388,7 @@ 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-3.12.24-rt37/include/net/netns/ipv4.h
===================================================================
--- linux-3.12.24-rt37.orig/include/net/netns/ipv4.h
+++ linux-3.12.24-rt37/include/net/netns/ipv4.h
@@ -57,6 +57,7 @@ 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-3.12.24-rt37/include/trace/events/hist.h
===================================================================
--- /dev/null
+++ linux-3.12.24-rt37/include/trace/events/hist.h
@@ -0,0 +1,72 @@
+#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-3.12.24-rt37/include/trace/events/latency_hist.h
===================================================================
--- /dev/null
+++ linux-3.12.24-rt37/include/trace/events/latency_hist.h
@@ -0,0 +1,29 @@
+#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-3.12.24-rt37/init/Kconfig
===================================================================
--- linux-3.12.24-rt37.orig/init/Kconfig
+++ linux-3.12.24-rt37/init/Kconfig
@@ -615,7 +615,7 @@ 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
@@ -642,7 +642,7 @@ 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.
@@ -1042,6 +1042,7 @@ 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
@@ -1582,6 +1583,7 @@ 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
@@ -1600,6 +1602,7 @@ 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-3.12.24-rt37/init/Makefile
===================================================================
--- linux-3.12.24-rt37.orig/init/Makefile
+++ linux-3.12.24-rt37/init/Makefile
@@ -33,4 +33,4 @@ 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-3.12.24-rt37/init/main.c
===================================================================
--- linux-3.12.24-rt37.orig/init/main.c
+++ linux-3.12.24-rt37/init/main.c
@@ -6,7 +6,7 @@
  *  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 */
@@ -74,6 +74,7 @@
 #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>
@@ -507,6 +508,7 @@ 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-3.12.24-rt37/ipc/mqueue.c
===================================================================
--- linux-3.12.24-rt37.orig/ipc/mqueue.c
+++ linux-3.12.24-rt37/ipc/mqueue.c
@@ -923,12 +923,17 @@ 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()
@@ -942,13 +947,18 @@ 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-3.12.24-rt37/ipc/msg.c
===================================================================
--- linux-3.12.24-rt37.orig/ipc/msg.c
+++ linux-3.12.24-rt37/ipc/msg.c
@@ -253,10 +253,18 @@ 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();
        }
 }
 
@@ -636,6 +644,12 @@ 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;
@@ -649,9 +663,11 @@ 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-3.12.24-rt37/ipc/sem.c
===================================================================
--- linux-3.12.24-rt37.orig/ipc/sem.c
+++ linux-3.12.24-rt37/ipc/sem.c
@@ -666,6 +666,13 @@ 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
@@ -677,6 +684,7 @@ static void wake_up_sem_queue_prepare(st
        q->pid = error;
 
        list_add_tail(&q->list, pt);
+#endif
 }
 
 /**
@@ -690,6 +698,7 @@ 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;
 
@@ -702,6 +711,7 @@ 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-3.12.24-rt37/kernel/Kconfig.locks
===================================================================
--- linux-3.12.24-rt37.orig/kernel/Kconfig.locks
+++ linux-3.12.24-rt37/kernel/Kconfig.locks
@@ -222,4 +222,4 @@ endif
 
 config MUTEX_SPIN_ON_OWNER
        def_bool y
-       depends on SMP && !DEBUG_MUTEXES
+       depends on SMP && !DEBUG_MUTEXES && !PREEMPT_RT_FULL
Index: linux-3.12.24-rt37/kernel/Kconfig.preempt
===================================================================
--- linux-3.12.24-rt37.orig/kernel/Kconfig.preempt
+++ linux-3.12.24-rt37/kernel/Kconfig.preempt
@@ -1,3 +1,16 @@
+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"
@@ -33,9 +46,9 @@ 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
@@ -52,6 +65,22 @@ 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-3.12.24-rt37/kernel/Makefile
===================================================================
--- linux-3.12.24-rt37.orig/kernel/Makefile
+++ linux-3.12.24-rt37/kernel/Makefile
@@ -7,10 +7,10 @@ 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
@@ -33,7 +33,11 @@ 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
@@ -45,6 +49,7 @@ 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-3.12.24-rt37/kernel/cpu.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/cpu.c
+++ linux-3.12.24-rt37/kernel/cpu.c
@@ -63,6 +63,290 @@ 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();
@@ -79,15 +363,14 @@ 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);
 
@@ -282,13 +565,15 @@ 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;
@@ -296,7 +581,34 @@ 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) {
@@ -306,8 +618,13 @@ 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. */
@@ -336,9 +653,14 @@ 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-3.12.24-rt37/kernel/debug/kdb/kdb_io.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/debug/kdb/kdb_io.c
+++ linux-3.12.24-rt37/kernel/debug/kdb/kdb_io.c
@@ -554,7 +554,6 @@ 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;
@@ -565,8 +564,6 @@ 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,
@@ -833,7 +830,6 @@ kdb_print_out:
        } else {
                __release(kdb_printf_lock);
        }
-       kdb_trap_printk = saved_trap_printk;
        preempt_enable();
        return retlen;
 }
@@ -843,9 +839,11 @@ 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-3.12.24-rt37/kernel/events/core.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/events/core.c
+++ linux-3.12.24-rt37/kernel/events/core.c
@@ -6046,6 +6046,7 @@ 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-3.12.24-rt37/kernel/exit.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/exit.c
+++ linux-3.12.24-rt37/kernel/exit.c
@@ -146,7 +146,7 @@ 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-3.12.24-rt37/kernel/fork.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/fork.c
+++ linux-3.12.24-rt37/kernel/fork.c
@@ -94,7 +94,7 @@ 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)
@@ -230,7 +230,9 @@ 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);
@@ -245,7 +247,18 @@ 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) { }
 
@@ -598,6 +611,19 @@ 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.
  */
@@ -1112,6 +1138,9 @@ 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;
@@ -1240,6 +1269,7 @@ 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;
@@ -1247,7 +1277,8 @@ 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
@@ -1300,6 +1331,9 @@ 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;
@@ -1667,7 +1701,7 @@ 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-3.12.24-rt37/kernel/futex.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/futex.c
+++ linux-3.12.24-rt37/kernel/futex.c
@@ -575,7 +575,9 @@ 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;
                }
 
@@ -1574,6 +1576,16 @@ 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;
@@ -2416,7 +2428,7 @@ 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;
@@ -2441,8 +2453,7 @@ 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))
@@ -2472,20 +2483,55 @@ 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(&current->pi_lock);
+       if (current->pi_blocked_on) {
+               /*
+                * We have been requeued or are in the process of
+                * being requeued.
+                */
+               raw_spin_unlock_irq(&current->pi_lock);
+       } else {
+               /*
+                * Setting pi_blocked_on to PI_WAKEUP_INPROGRESS
+                * prevents a concurrent requeue from moving us to the
+                * uaddr2 rtmutex. After that we can safely acquire
+                * (and possibly block on) hb->lock.
+                */
+               current->pi_blocked_on = PI_WAKEUP_INPROGRESS;
+               raw_spin_unlock_irq(&current->pi_lock);
+
+               spin_lock(&hb->lock);
+
+               /*
+                * Clean up pi_blocked_on. We might leak it otherwise
+                * when we succeeded with the hb->lock in the fast
+                * path.
+                */
+               raw_spin_lock_irq(&current->pi_lock);
+               current->pi_blocked_on = NULL;
+               raw_spin_unlock_irq(&current->pi_lock);
+
+               ret = handle_early_requeue_pi_wakeup(hb, &q, &key2, to);
+               spin_unlock(&hb->lock);
+               if (ret)
+                       goto out_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) {
@@ -2494,9 +2540,10 @@ 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 {
                /*
@@ -2509,7 +2556,8 @@ 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-3.12.24-rt37/kernel/hrtimer.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/hrtimer.c
+++ linux-3.12.24-rt37/kernel/hrtimer.c
@@ -47,11 +47,13 @@
 #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:
@@ -629,8 +631,7 @@ 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;
@@ -665,6 +666,9 @@ 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
  */
@@ -681,9 +685,18 @@ 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)
@@ -751,6 +764,44 @@ 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.
@@ -759,6 +810,7 @@ void clock_was_set_delayed(void)
 {
        schedule_work(&hrtimer_work);
 }
+#endif
 
 #else
 
@@ -768,12 +820,18 @@ 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 */
 
@@ -892,6 +950,32 @@ 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
  *
@@ -935,6 +1019,11 @@ 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) {
@@ -1021,6 +1110,17 @@ 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);
@@ -1031,9 +1131,19 @@ 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.
@@ -1041,9 +1151,7 @@ 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;
                }
        }
 
@@ -1133,7 +1241,7 @@ int hrtimer_cancel(struct hrtimer *timer
 
                if (ret >= 0)
                        return ret;
-               cpu_relax();
+               hrtimer_wait_for_timer(timer);
        }
 }
 EXPORT_SYMBOL_GPL(hrtimer_cancel);
@@ -1212,6 +1320,7 @@ 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
@@ -1295,6 +1404,126 @@ 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
 
 /*
@@ -1305,7 +1534,7 @@ 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++;
@@ -1340,6 +1569,15 @@ 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
@@ -1365,7 +1603,10 @@ retry:
                                break;
                        }
 
-                       __run_hrtimer(timer, &basenow);
+                       if (!hrtimer_rt_defer(timer))
+                               __run_hrtimer(timer, &basenow);
+                       else
+                               raise = 1;
                }
        }
 
@@ -1380,7 +1621,7 @@ retry:
        if (expires_next.tv64 == KTIME_MAX ||
            !tick_program_event(expires_next, 0)) {
                cpu_base->hang_detected = 0;
-               return;
+               goto out;
        }
 
        /*
@@ -1424,6 +1665,9 @@ 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);
 }
 
 /*
@@ -1459,40 +1703,16 @@ 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();
 }
 
 /*
@@ -1503,11 +1723,18 @@ 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))
@@ -1528,10 +1755,16 @@ 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);
 }
 
 /*
@@ -1553,16 +1786,18 @@ 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;
@@ -1606,7 +1841,8 @@ 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;
@@ -1623,8 +1859,10 @@ 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;
@@ -1637,7 +1875,7 @@ 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: */
@@ -1664,6 +1902,12 @@ 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)
 {
@@ -1678,6 +1922,26 @@ 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:
  */
@@ -1689,9 +1953,13 @@ 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
@@ -1804,9 +2072,7 @@ 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-3.12.24-rt37/kernel/irq/handle.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/irq/handle.c
+++ linux-3.12.24-rt37/kernel/irq/handle.c
@@ -132,6 +132,8 @@ 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;
 
@@ -172,7 +174,11 @@ 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-3.12.24-rt37/kernel/irq/manage.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/irq/manage.c
+++ linux-3.12.24-rt37/kernel/irq/manage.c
@@ -22,6 +22,7 @@
 #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)
@@ -30,6 +31,7 @@ static int __init setup_forced_irqthread
        return 0;
 }
 early_param("threadirqs", setup_forced_irqthreads);
+# endif
 #endif
 
 /**
@@ -162,6 +164,62 @@ 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(&notify->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)
 {
@@ -181,7 +239,17 @@ 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);
 
@@ -216,10 +284,8 @@ 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;
@@ -241,6 +307,13 @@ out:
        kref_put(&notify->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
@@ -270,6 +343,8 @@ irq_set_affinity_notifier(unsigned int i
                notify->irq = irq;
                kref_init(&notify->kref);
                INIT_WORK(&notify->work, irq_affinity_notify);
+               INIT_LIST_HEAD(&notify->list);
+               init_helper_thread();
        }
 
        raw_spin_lock_irqsave(&desc->lock, flags);
@@ -776,7 +851,15 @@ 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;
 }
 
@@ -859,6 +942,12 @@ 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);
        }
 
@@ -1121,6 +1210,9 @@ __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-3.12.24-rt37/kernel/irq/settings.h
===================================================================
--- linux-3.12.24-rt37.orig/kernel/irq/settings.h
+++ linux-3.12.24-rt37/kernel/irq/settings.h
@@ -14,6 +14,7 @@ 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,
 };
 
@@ -26,6 +27,7 @@ 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
 
@@ -36,6 +38,16 @@ 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-3.12.24-rt37/kernel/irq/spurious.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/irq/spurious.c
+++ linux-3.12.24-rt37/kernel/irq/spurious.c
@@ -438,6 +438,10 @@ 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");
@@ -450,6 +454,10 @@ 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-3.12.24-rt37/kernel/irq_work.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/irq_work.c
+++ linux-3.12.24-rt37/kernel/irq_work.c
@@ -20,6 +20,9 @@
 
 
 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);
 
 /*
@@ -48,7 +51,11 @@ 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
@@ -70,8 +77,12 @@ 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
@@ -115,12 +126,18 @@ 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);
@@ -152,7 +169,9 @@ 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-3.12.24-rt37/kernel/itimer.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/itimer.c
+++ linux-3.12.24-rt37/kernel/itimer.c
@@ -213,6 +213,7 @@ 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-3.12.24-rt37/kernel/ksysfs.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/ksysfs.c
+++ linux-3.12.24-rt37/kernel/ksysfs.c
@@ -132,6 +132,15 @@ 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)
@@ -197,6 +206,9 @@ 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-3.12.24-rt37/kernel/lglock.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/lglock.c
+++ linux-3.12.24-rt37/kernel/lglock.c
@@ -4,6 +4,15 @@
 #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)
@@ -12,51 +21,60 @@
 
 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);
 
@@ -64,12 +82,12 @@ 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);
@@ -80,10 +98,10 @@ 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-3.12.24-rt37/kernel/lockdep.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/lockdep.c
+++ linux-3.12.24-rt37/kernel/lockdep.c
@@ -3541,6 +3541,7 @@ 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
@@ -3555,6 +3556,7 @@ static void check_flags(unsigned long fl
                        DEBUG_LOCKS_WARN_ON(!current->softirqs_enabled);
                }
        }
+#endif
 
        if (!debug_locks)
                print_irqtrace_events(current);
Index: linux-3.12.24-rt37/kernel/panic.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/panic.c
+++ linux-3.12.24-rt37/kernel/panic.c
@@ -368,9 +368,11 @@ 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-3.12.24-rt37/kernel/posix-cpu-timers.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/posix-cpu-timers.c
+++ linux-3.12.24-rt37/kernel/posix-cpu-timers.c
@@ -3,6 +3,7 @@
  */
 
 #include <linux/sched.h>
+#include <linux/sched/rt.h>
 #include <linux/posix-timers.h>
 #include <linux/errno.h>
 #include <linux/math64.h>
@@ -663,7 +664,7 @@ 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;
@@ -1110,7 +1111,7 @@ 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);
 
@@ -1177,10 +1178,11 @@ 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;
@@ -1194,13 +1196,13 @@ 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
@@ -1265,6 +1267,190 @@ 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, &param);
+               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-3.12.24-rt37/kernel/posix-timers.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/posix-timers.c
+++ linux-3.12.24-rt37/kernel/posix-timers.c
@@ -497,6 +497,7 @@ 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)) ||
@@ -505,7 +506,8 @@ 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);
@@ -816,6 +818,20 @@ 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
@@ -893,6 +909,7 @@ 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;
@@ -901,9 +918,12 @@ 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)))
@@ -941,10 +961,15 @@ 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(&current->sighand->siglock);
        list_del(&timer->list);
@@ -970,8 +995,18 @@ 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-3.12.24-rt37/kernel/power/hibernate.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/power/hibernate.c
+++ linux-3.12.24-rt37/kernel/power/hibernate.c
@@ -275,6 +275,8 @@ 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, "
@@ -302,6 +304,7 @@ static int create_image(int platform_mod
        syscore_resume();
 
  Enable_irqs:
+       system_state = SYSTEM_RUNNING;
        local_irq_enable();
 
  Enable_cpus:
@@ -427,6 +430,7 @@ static int resume_target_kernel(bool pla
                goto Enable_cpus;
 
        local_irq_disable();
+       system_state = SYSTEM_SUSPEND;
 
        error = syscore_suspend();
        if (error)
@@ -460,6 +464,7 @@ static int resume_target_kernel(bool pla
        syscore_resume();
 
  Enable_irqs:
+       system_state = SYSTEM_RUNNING;
        local_irq_enable();
 
  Enable_cpus:
@@ -542,6 +547,7 @@ int hibernation_platform_enter(void)
                goto Platform_finish;
 
        local_irq_disable();
+       system_state = SYSTEM_SUSPEND;
        syscore_suspend();
        if (pm_wakeup_pending()) {
                error = -EAGAIN;
@@ -554,6 +560,7 @@ int hibernation_platform_enter(void)
 
  Power_up:
        syscore_resume();
+       system_state = SYSTEM_RUNNING;
        local_irq_enable();
        enable_nonboot_cpus();
 
Index: linux-3.12.24-rt37/kernel/power/suspend.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/power/suspend.c
+++ linux-3.12.24-rt37/kernel/power/suspend.c
@@ -218,6 +218,8 @@ 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();
@@ -228,6 +230,8 @@ static int suspend_enter(suspend_state_t
                syscore_resume();
        }
 
+       system_state = SYSTEM_RUNNING;
+
        arch_suspend_enable_irqs();
        BUG_ON(irqs_disabled());
 
Index: linux-3.12.24-rt37/kernel/printk/printk.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/printk/printk.c
+++ linux-3.12.24-rt37/kernel/printk/printk.c
@@ -1029,6 +1029,7 @@ 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)
@@ -1040,7 +1041,14 @@ 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;
@@ -1061,6 +1069,14 @@ 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 */
@@ -1074,6 +1090,14 @@ 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 */
@@ -1114,6 +1138,7 @@ 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);
@@ -1271,6 +1296,7 @@ static void call_console_drivers(int lev
        if (!console_drivers)
                return;
 
+       migrate_disable();
        for_each_console(con) {
                if (exclusive_console && con != exclusive_console)
                        continue;
@@ -1283,6 +1309,7 @@ static void call_console_drivers(int lev
                        continue;
                con->write(con, text, len);
        }
+       migrate_enable();
 }
 
 /*
@@ -1342,12 +1369,18 @@ 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;
 
                /*
@@ -1487,6 +1520,62 @@ 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)
@@ -1500,6 +1589,13 @@ 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();
 
@@ -1619,8 +1715,15 @@ 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:
@@ -1722,29 +1825,6 @@ 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)
 {
@@ -1985,11 +2065,16 @@ 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);
@@ -2072,12 +2157,17 @@ 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-3.12.24-rt37/kernel/ptrace.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/ptrace.c
+++ linux-3.12.24-rt37/kernel/ptrace.c
@@ -135,7 +135,12 @@ 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-3.12.24-rt37/kernel/rcupdate.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/rcupdate.c
+++ linux-3.12.24-rt37/kernel/rcupdate.c
@@ -129,6 +129,7 @@ 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?
  *
@@ -155,6 +156,7 @@ 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-3.12.24-rt37/kernel/rcutiny.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/rcutiny.c
+++ linux-3.12.24-rt37/kernel/rcutiny.c
@@ -369,6 +369,7 @@ 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.
@@ -378,6 +379,7 @@ 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-3.12.24-rt37/kernel/rcutree.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/rcutree.c
+++ linux-3.12.24-rt37/kernel/rcutree.c
@@ -55,6 +55,11 @@
 #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>
@@ -145,8 +150,6 @@ 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.
@@ -156,8 +159,6 @@ 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);
@@ -199,6 +200,19 @@ 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);
@@ -207,6 +221,7 @@ 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,
@@ -263,6 +278,7 @@ 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.
  */
@@ -280,6 +296,7 @@ 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
@@ -1471,7 +1488,7 @@ 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) &&
@@ -1490,7 +1507,7 @@ 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)),
@@ -1528,7 +1545,7 @@ 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);
 }
 
 /*
@@ -1602,7 +1619,7 @@ 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. */
 }
 
 /*
@@ -2172,7 +2189,8 @@ 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);
 }
 
 /*
@@ -2209,16 +2227,14 @@ __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"));
 }
 
 /*
@@ -2232,18 +2248,105 @@ 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.
@@ -2373,6 +2476,7 @@ 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.
  */
@@ -2381,6 +2485,7 @@ 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,
@@ -2458,6 +2563,7 @@ 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.
  *
@@ -2484,6 +2590,7 @@ 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)
 {
@@ -2658,6 +2765,10 @@ 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) {
@@ -2891,6 +3002,7 @@ 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.
  */
@@ -2899,6 +3011,7 @@ 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.
@@ -3202,7 +3315,7 @@ 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) {
@@ -3298,7 +3411,6 @@ 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-3.12.24-rt37/kernel/rcutree.h
===================================================================
--- linux-3.12.24-rt37.orig/kernel/rcutree.h
+++ linux-3.12.24-rt37/kernel/rcutree.h
@@ -28,6 +28,7 @@
 #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
@@ -200,7 +201,7 @@ 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];
@@ -333,7 +334,7 @@ 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 */
 
@@ -403,7 +404,7 @@ 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. */
@@ -527,10 +528,9 @@ 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 */
@@ -564,6 +564,7 @@ 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-3.12.24-rt37/kernel/rcutree_plugin.h
===================================================================
--- linux-3.12.24-rt37.orig/kernel/rcutree_plugin.h
+++ linux-3.12.24-rt37/kernel/rcutree_plugin.h
@@ -24,12 +24,6 @@
  *        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
@@ -359,7 +353,7 @@ 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;
        }
@@ -656,15 +650,6 @@ 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.
  */
@@ -1126,6 +1111,19 @@ 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"
@@ -1157,16 +1155,6 @@ 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
@@ -1310,23 +1298,6 @@ 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.
  */
@@ -1380,67 +1351,6 @@ 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
@@ -1474,27 +1384,14 @@ 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) {
@@ -1522,11 +1419,6 @@ 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;
@@ -1553,7 +1445,7 @@ 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
@@ -1569,6 +1461,9 @@ 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
@@ -1666,6 +1561,8 @@ 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
@@ -1704,6 +1601,7 @@ 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
@@ -2061,7 +1959,7 @@ 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]);
 }
 
 /*
@@ -2079,8 +1977,8 @@ 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? */
@@ -2120,7 +2018,7 @@ 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. */
@@ -2210,7 +2108,7 @@ 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))
@@ -2238,7 +2136,7 @@ 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);
@@ -2288,7 +2186,7 @@ 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. */
@@ -2803,3 +2701,23 @@ 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-3.12.24-rt37/kernel/relay.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/relay.c
+++ linux-3.12.24-rt37/kernel/relay.c
@@ -339,6 +339,10 @@ 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);
 }
 
 /**
@@ -356,6 +360,7 @@ 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);
 
@@ -739,15 +744,6 @@ 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-3.12.24-rt37/kernel/res_counter.c
===================================================================
--- linux-3.12.24-rt37.orig/kernel/res_counter.c
+++ linux-3.12.24-rt37/kernel/res_counter.c
@@ -49,7 +49,7 @@ 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);
@@ -69,7 +69,7 @@ static int __res_counter_charge(struct r
                        spin_unlock(&u->lock);
                }
        }
-       local_irq_restore(flags);
+       local_irq_restore_nort(flags);
 
        return ret;
 }
@@ -103,7 +103,7 @@ 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);
@@ -112,7 +112,7 @@ 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-3.12.24-rt37/kernel/rt.c
===================================================================
--- /dev/null
+++ linux-3.12.24-rt37/kernel/rt.c
@@ -0,0 +1,456 @@
+/*
+ * 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_);