linux: update to 4.6.5, add realtime patch

11 files changed, 26647 insertions, 5 deletions

diff --git a/mk/kernel-ver.mk b/mk/kernel-ver.mk
index d147aff5d..7b345505e 100644
--- a/mk/kernel-ver.mk
+++ b/mk/kernel-ver.mk
@@ -20,10 +20,10 @@ KERNEL_RELEASE:=	1
 KERNEL_VERSION:=	$(KERNEL_FILE_VER)-$(KERNEL_RELEASE)
 endif
 ifeq ($(ADK_TARGET_KERNEL_VERSION_4_6),y)
-KERNEL_FILE_VER:=	4.6.4
+KERNEL_FILE_VER:=	4.6.5
 KERNEL_RELEASE:=	1
 KERNEL_VERSION:=	$(KERNEL_FILE_VER)-$(KERNEL_RELEASE)
-KERNEL_HASH:=		8568d41c7104e941989b14a380d167129f83db42c04e950d8d9337fe6012ff7e
+KERNEL_HASH:=		7e2d53c8a36a159c444be8f452eae898fadc1f1862fe470a36c836c3d1d613c5
 endif
 ifeq ($(ADK_TARGET_KERNEL_VERSION_4_5),y)
 KERNEL_FILE_VER:=	4.5.7
diff --git a/target/config/Config.in.kernelversion b/target/config/Config.in.kernelversion
index 5a4199e94..653a332d2 100644
--- a/target/config/Config.in.kernelversion
+++ b/target/config/Config.in.kernelversion
@@ -21,7 +21,7 @@ config ADK_TARGET_KERNEL_VERSION_RPI
 	depends on ADK_TARGET_BOARD_BCM28XX
 
 config ADK_TARGET_KERNEL_VERSION_4_6
-	bool "4.6.4"
+	bool "4.6.5"
 	depends on !ADK_TARGET_ARCH_NDS32
 
 config ADK_TARGET_KERNEL_VERSION_4_5
diff --git a/target/cris/qemu-cris/patches/4.6.4/crisv32_ethernet_driver.patch b/target/cris/qemu-cris/patches/4.6.5/crisv32_ethernet_driver.patch
index 80f03383c..80f03383c 100644
--- a/target/cris/qemu-cris/patches/4.6.4/crisv32_ethernet_driver.patch
+++ b/target/cris/qemu-cris/patches/4.6.5/crisv32_ethernet_driver.patch
diff --git a/target/linux/config/Config.in.kernel b/target/linux/config/Config.in.kernel
index 924d0e6e6..704b4c3dd 100644
--- a/target/linux/config/Config.in.kernel
+++ b/target/linux/config/Config.in.kernel
@@ -143,7 +143,8 @@ config ADK_KERNEL_PREEMPT_RTB
 	select ADK_KERNEL_HIGH_RES_TIMERS
 	select ADK_KERNEL_PATCH_REALTIME
 	depends on ADK_TARGET_KERNEL_VERSION_4_1 \
-		|| ADK_TARGET_KERNEL_VERSION_4_4
+		|| ADK_TARGET_KERNEL_VERSION_4_4 \
+		|| ADK_TARGET_KERNEL_VERSION_4_6
         help
 	  Preemptible Kernel (Basic RT)
 
@@ -152,7 +153,8 @@ config ADK_KERNEL_PREEMPT_RT_FULL
 	select ADK_KERNEL_HIGH_RES_TIMERS
 	select ADK_KERNEL_PATCH_REALTIME
 	depends on ADK_TARGET_KERNEL_VERSION_4_1 \
-		|| ADK_TARGET_KERNEL_VERSION_4_4
+		|| ADK_TARGET_KERNEL_VERSION_4_4 \
+		|| ADK_TARGET_KERNEL_VERSION_4_6
         help
 	  Fully Preemptible Kernel (RealTime)
 	  https://www.kernel.org/pub/linux/kernel/projects/rt/
diff --git a/target/linux/patches/4.6.4/crisv32.patch b/target/linux/patches/4.6.5/crisv32.patch
index cb9b0d028..cb9b0d028 100644
--- a/target/linux/patches/4.6.4/crisv32.patch
+++ b/target/linux/patches/4.6.5/crisv32.patch
diff --git a/target/linux/patches/4.6.4/initramfs-nosizelimit.patch b/target/linux/patches/4.6.5/initramfs-nosizelimit.patch
index 40d2f6bd8..40d2f6bd8 100644
--- a/target/linux/patches/4.6.4/initramfs-nosizelimit.patch
+++ b/target/linux/patches/4.6.5/initramfs-nosizelimit.patch
diff --git a/target/linux/patches/4.6.4/ld-or1k.patch b/target/linux/patches/4.6.5/ld-or1k.patch
index 264f9166f..264f9166f 100644
--- a/target/linux/patches/4.6.4/ld-or1k.patch
+++ b/target/linux/patches/4.6.5/ld-or1k.patch
diff --git a/target/linux/patches/4.6.4/macsonic.patch b/target/linux/patches/4.6.5/macsonic.patch
index 75a6fcad2..75a6fcad2 100644
--- a/target/linux/patches/4.6.4/macsonic.patch
+++ b/target/linux/patches/4.6.5/macsonic.patch
diff --git a/target/linux/patches/4.6.5/patch-realtime b/target/linux/patches/4.6.5/patch-realtime
new file mode 100644
index 000000000..6fb397726
--- /dev/null
+++ b/target/linux/patches/4.6.5/patch-realtime
@@ -0,0 +1,26640 @@
+diff --git a/Documentation/hwlat_detector.txt b/Documentation/hwlat_detector.txt
+new file mode 100644
+index 000000000000..cb61516483d3
+--- /dev/null
++++ b/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.
+diff --git a/Documentation/sysrq.txt b/Documentation/sysrq.txt
+index 13f5619b2203..f64d075ba647 100644
+--- a/Documentation/sysrq.txt
++++ b/Documentation/sysrq.txt
+@@ -59,10 +59,17 @@ On PowerPC - Press 'ALT - Print Screen (or F13) - <command key>,
+ 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
+diff --git a/Documentation/trace/histograms.txt b/Documentation/trace/histograms.txt
+new file mode 100644
+index 000000000000..6f2aeabf7faa
+--- /dev/null
++++ b/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.
+diff --git a/arch/Kconfig b/arch/Kconfig
+index 81869a5e7e17..54cfbcbdaa02 100644
+--- a/arch/Kconfig
++++ b/arch/Kconfig
+@@ -9,6 +9,7 @@ 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
+@@ -52,6 +53,7 @@ config KPROBES
+ config JUMP_LABEL
+        bool "Optimize very unlikely/likely branches"
+        depends on HAVE_ARCH_JUMP_LABEL
++       depends on (!INTERRUPT_OFF_HIST && !PREEMPT_OFF_HIST && !WAKEUP_LATENCY_HIST && !MISSED_TIMER_OFFSETS_HIST)
+        help
+          This option enables a transparent branch optimization that
+ 	 makes certain almost-always-true or almost-always-false branch
+diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
+index cdfa6c2b7626..fa885f5eb8c9 100644
+--- a/arch/arm/Kconfig
++++ b/arch/arm/Kconfig
+@@ -35,7 +35,7 @@ config ARM
+ 	select HARDIRQS_SW_RESEND
+ 	select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT)
+ 	select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
+-	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
++	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU && !PREEMPT_RT_BASE
+ 	select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
+ 	select HAVE_ARCH_MMAP_RND_BITS if MMU
+ 	select HAVE_ARCH_SECCOMP_FILTER if (AEABI && !OABI_COMPAT)
+@@ -71,6 +71,7 @@ config ARM
+ 	select HAVE_PERF_EVENTS
+ 	select HAVE_PERF_REGS
+ 	select HAVE_PERF_USER_STACK_DUMP
++	select HAVE_PREEMPT_LAZY
+ 	select HAVE_RCU_TABLE_FREE if (SMP && ARM_LPAE)
+ 	select HAVE_REGS_AND_STACK_ACCESS_API
+ 	select HAVE_SYSCALL_TRACEPOINTS
+diff --git a/arch/arm/include/asm/switch_to.h b/arch/arm/include/asm/switch_to.h
+index 12ebfcc1d539..c962084605bc 100644
+--- a/arch/arm/include/asm/switch_to.h
++++ b/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
+@@ -25,6 +32,7 @@ extern struct task_struct *__switch_to(struct task_struct *, struct thread_info
+ #define switch_to(prev,next,last)					\
+ do {									\
+ 	__complete_pending_tlbi();					\
++	switch_kmaps(prev, next);					\
+ 	last = __switch_to(prev,task_thread_info(prev), task_thread_info(next));	\
+ } while (0)
+ 
+diff --git a/arch/arm/include/asm/thread_info.h b/arch/arm/include/asm/thread_info.h
+index 776757d1604a..1f36a4eccc72 100644
+--- a/arch/arm/include/asm/thread_info.h
++++ b/arch/arm/include/asm/thread_info.h
+@@ -49,6 +49,7 @@ struct cpu_context_save {
+ struct thread_info {
+ 	unsigned long		flags;		/* low level flags */
+ 	int			preempt_count;	/* 0 => preemptable, <0 => bug */
++	int			preempt_lazy_count; /* 0 => preemptable, <0 => bug */
+ 	mm_segment_t		addr_limit;	/* address limit */
+ 	struct task_struct	*task;		/* main task structure */
+ 	__u32			cpu;		/* cpu */
+@@ -142,7 +143,8 @@ extern int vfp_restore_user_hwstate(struct user_vfp __user *,
+ #define TIF_SYSCALL_TRACE	4	/* syscall trace active */
+ #define TIF_SYSCALL_AUDIT	5	/* syscall auditing active */
+ #define TIF_SYSCALL_TRACEPOINT	6	/* syscall tracepoint instrumentation */
+-#define TIF_SECCOMP		7	/* seccomp syscall filtering active */
++#define TIF_SECCOMP		8	/* seccomp syscall filtering active */
++#define TIF_NEED_RESCHED_LAZY	7
+ 
+ #define TIF_NOHZ		12	/* in adaptive nohz mode */
+ #define TIF_USING_IWMMXT	17
+@@ -152,6 +154,7 @@ extern int vfp_restore_user_hwstate(struct user_vfp __user *,
+ #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
+ #define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
+ #define _TIF_NOTIFY_RESUME	(1 << TIF_NOTIFY_RESUME)
++#define _TIF_NEED_RESCHED_LAZY	(1 << TIF_NEED_RESCHED_LAZY)
+ #define _TIF_UPROBE		(1 << TIF_UPROBE)
+ #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
+ #define _TIF_SYSCALL_AUDIT	(1 << TIF_SYSCALL_AUDIT)
+@@ -167,7 +170,8 @@ extern int vfp_restore_user_hwstate(struct user_vfp __user *,
+  * Change these and you break ASM code in entry-common.S
+  */
+ #define _TIF_WORK_MASK		(_TIF_NEED_RESCHED | _TIF_SIGPENDING | \
+-				 _TIF_NOTIFY_RESUME | _TIF_UPROBE)
++				 _TIF_NOTIFY_RESUME | _TIF_UPROBE | \
++				 _TIF_NEED_RESCHED_LAZY)
+ 
+ #endif /* __KERNEL__ */
+ #endif /* __ASM_ARM_THREAD_INFO_H */
+diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c
+index 27d05813ff09..5a3742215cde 100644
+--- a/arch/arm/kernel/asm-offsets.c
++++ b/arch/arm/kernel/asm-offsets.c
+@@ -65,6 +65,7 @@ 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_CPU,		offsetof(struct thread_info, cpu));
+diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S
+index e2550500486d..3125de9e9783 100644
+--- a/arch/arm/kernel/entry-armv.S
++++ b/arch/arm/kernel/entry-armv.S
+@@ -215,11 +215,18 @@ ENDPROC(__dabt_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
+@@ -234,8 +241,14 @@ ENDPROC(__irq_svc)
+ 1:	bl	preempt_schedule_irq		@ irq en/disable is done inside
+ 	ldr	r0, [tsk, #TI_FLAGS]		@ get new tasks TI_FLAGS
+ 	tst	r0, #_TIF_NEED_RESCHED
++	bne	1b
++	tst	r0, #_TIF_NEED_RESCHED_LAZY
+ 	reteq	r8				@ go again
+-	b	1b
++	ldr	r0, [tsk, #TI_PREEMPT_LAZY]	@ get preempt lazy count
++	teq	r0, #0				@ if preempt lazy count != 0
++	beq	1b
++	ret	r8				@ go again
++
+ #endif
+ 
+ __und_fault:
+diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S
+index 30a7228eaceb..c3bd6cbfce4b 100644
+--- a/arch/arm/kernel/entry-common.S
++++ b/arch/arm/kernel/entry-common.S
+@@ -36,7 +36,9 @@
+  UNWIND(.cantunwind	)
+ 	disable_irq_notrace			@ disable interrupts
+ 	ldr	r1, [tsk, #TI_FLAGS]		@ re-check for syscall tracing
+-	tst	r1, #_TIF_SYSCALL_WORK | _TIF_WORK_MASK
++	tst	r1, #((_TIF_SYSCALL_WORK | _TIF_WORK_MASK) & ~_TIF_SECCOMP)
++	bne	fast_work_pending
++	tst	r1, #_TIF_SECCOMP
+ 	bne	fast_work_pending
+ 
+ 	/* perform architecture specific actions before user return */
+@@ -62,8 +64,11 @@ ENDPROC(ret_fast_syscall)
+ 	str	r0, [sp, #S_R0 + S_OFF]!	@ save returned r0
+ 	disable_irq_notrace			@ disable interrupts
+ 	ldr	r1, [tsk, #TI_FLAGS]		@ re-check for syscall tracing
+-	tst	r1, #_TIF_SYSCALL_WORK | _TIF_WORK_MASK
++	tst	r1, #((_TIF_SYSCALL_WORK | _TIF_WORK_MASK) & ~_TIF_SECCOMP)
++	bne 	do_slower_path
++	tst	r1, #_TIF_SECCOMP
+ 	beq	no_work_pending
++do_slower_path:
+  UNWIND(.fnend		)
+ ENDPROC(ret_fast_syscall)
+ 
+diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c
+index 4adfb46e3ee9..15f1d94b47c5 100644
+--- a/arch/arm/kernel/process.c
++++ b/arch/arm/kernel/process.c
+@@ -319,6 +319,30 @@ unsigned long arch_randomize_brk(struct mm_struct *mm)
+ }
+ 
+ #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
+diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c
+index 7b8f2141427b..96541e00b74a 100644
+--- a/arch/arm/kernel/signal.c
++++ b/arch/arm/kernel/signal.c
+@@ -572,7 +572,8 @@ do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall)
+ 	 */
+ 	trace_hardirqs_off();
+ 	do {
+-		if (likely(thread_flags & _TIF_NEED_RESCHED)) {
++		if (likely(thread_flags & (_TIF_NEED_RESCHED |
++					   _TIF_NEED_RESCHED_LAZY))) {
+ 			schedule();
+ 		} else {
+ 			if (unlikely(!user_mode(regs)))
+diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
+index baee70267f29..ad157ec494f9 100644
+--- a/arch/arm/kernel/smp.c
++++ b/arch/arm/kernel/smp.c
+@@ -234,8 +234,6 @@ int __cpu_disable(void)
+ 	flush_cache_louis();
+ 	local_flush_tlb_all();
+ 
+-	clear_tasks_mm_cpumask(cpu);
+-
+ 	return 0;
+ }
+ 
+@@ -251,6 +249,9 @@ void __cpu_die(unsigned int cpu)
+ 		pr_err("CPU%u: cpu didn't die\n", cpu);
+ 		return;
+ 	}
++
++	clear_tasks_mm_cpumask(cpu);
++
+ 	pr_notice("CPU%u: shutdown\n", cpu);
+ 
+ 	/*
+diff --git a/arch/arm/kernel/unwind.c b/arch/arm/kernel/unwind.c
+index 0bee233fef9a..314cfb232a63 100644
+--- a/arch/arm/kernel/unwind.c
++++ b/arch/arm/kernel/unwind.c
+@@ -93,7 +93,7 @@ extern const struct unwind_idx __start_unwind_idx[];
+ 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 */
+@@ -201,7 +201,7 @@ static const struct unwind_idx *unwind_find_idx(unsigned long addr)
+ 		/* 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) {
+@@ -213,7 +213,7 @@ static const struct unwind_idx *unwind_find_idx(unsigned long addr)
+ 				break;
+ 			}
+ 		}
+-		spin_unlock_irqrestore(&unwind_lock, flags);
++		raw_spin_unlock_irqrestore(&unwind_lock, flags);
+ 	}
+ 
+ 	pr_debug("%s: idx = %p\n", __func__, idx);
+@@ -529,9 +529,9 @@ struct unwind_table *unwind_table_add(unsigned long start, unsigned long size,
+ 	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;
+ }
+@@ -543,9 +543,9 @@ void unwind_table_del(struct unwind_table *tab)
+ 	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);
+ }
+diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
+index 72b11d91ede2..34068c59d0c5 100644
+--- a/arch/arm/kvm/arm.c
++++ b/arch/arm/kvm/arm.c
+@@ -582,7 +582,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
+ 		 * involves poking the GIC, which must be done in a
+ 		 * non-preemptible context.
+ 		 */
+-		preempt_disable();
++		migrate_disable();
+ 		kvm_pmu_flush_hwstate(vcpu);
+ 		kvm_timer_flush_hwstate(vcpu);
+ 		kvm_vgic_flush_hwstate(vcpu);
+@@ -603,7 +603,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
+ 			kvm_pmu_sync_hwstate(vcpu);
+ 			kvm_timer_sync_hwstate(vcpu);
+ 			kvm_vgic_sync_hwstate(vcpu);
+-			preempt_enable();
++			migrate_enable();
+ 			continue;
+ 		}
+ 
+@@ -659,7 +659,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
+ 
+ 		kvm_vgic_sync_hwstate(vcpu);
+ 
+-		preempt_enable();
++		migrate_enable();
+ 
+ 		ret = handle_exit(vcpu, run, ret);
+ 	}
+diff --git a/arch/arm/mach-exynos/platsmp.c b/arch/arm/mach-exynos/platsmp.c
+index 85c3be63d644..8a950aec7834 100644
+--- a/arch/arm/mach-exynos/platsmp.c
++++ b/arch/arm/mach-exynos/platsmp.c
+@@ -229,7 +229,7 @@ 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)
+ {
+@@ -242,8 +242,8 @@ static void exynos_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 exynos_set_boot_addr(u32 core_id, unsigned long boot_addr)
+@@ -307,7 +307,7 @@ static int exynos_boot_secondary(unsigned int cpu, struct task_struct *idle)
+ 	 * 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
+@@ -334,7 +334,7 @@ static int exynos_boot_secondary(unsigned int cpu, struct task_struct *idle)
+ 
+ 		if (timeout == 0) {
+ 			printk(KERN_ERR "cpu1 power enable failed");
+-			spin_unlock(&boot_lock);
++			raw_spin_unlock(&boot_lock);
+ 			return -ETIMEDOUT;
+ 		}
+ 	}
+@@ -380,7 +380,7 @@ static int exynos_boot_secondary(unsigned int cpu, struct task_struct *idle)
+ 	 * calibrations, then wait for it to finish
+ 	 */
+ fail:
+-	spin_unlock(&boot_lock);
++	raw_spin_unlock(&boot_lock);
+ 
+ 	return pen_release != -1 ? ret : 0;
+ }
+diff --git a/arch/arm/mach-hisi/platmcpm.c b/arch/arm/mach-hisi/platmcpm.c
+index 4b653a8cb75c..b03d5a922cb1 100644
+--- a/arch/arm/mach-hisi/platmcpm.c
++++ b/arch/arm/mach-hisi/platmcpm.c
+@@ -61,7 +61,7 @@
+ 
+ static void __iomem *sysctrl, *fabric;
+ static int hip04_cpu_table[HIP04_MAX_CLUSTERS][HIP04_MAX_CPUS_PER_CLUSTER];
+-static DEFINE_SPINLOCK(boot_lock);
++static DEFINE_RAW_SPINLOCK(boot_lock);
+ static u32 fabric_phys_addr;
+ /*
+  * [0]: bootwrapper physical address
+@@ -113,7 +113,7 @@ static int hip04_boot_secondary(unsigned int l_cpu, struct task_struct *idle)
+ 	if (cluster >= HIP04_MAX_CLUSTERS || cpu >= HIP04_MAX_CPUS_PER_CLUSTER)
+ 		return -EINVAL;
+ 
+-	spin_lock_irq(&boot_lock);
++	raw_spin_lock_irq(&boot_lock);
+ 
+ 	if (hip04_cpu_table[cluster][cpu])
+ 		goto out;
+@@ -147,7 +147,7 @@ static int hip04_boot_secondary(unsigned int l_cpu, struct task_struct *idle)
+ 
+ out:
+ 	hip04_cpu_table[cluster][cpu]++;
+-	spin_unlock_irq(&boot_lock);
++	raw_spin_unlock_irq(&boot_lock);
+ 
+ 	return 0;
+ }
+@@ -162,11 +162,11 @@ static void hip04_cpu_die(unsigned int l_cpu)
+ 	cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+ 	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
+ 
+-	spin_lock(&boot_lock);
++	raw_spin_lock(&boot_lock);
+ 	hip04_cpu_table[cluster][cpu]--;
+ 	if (hip04_cpu_table[cluster][cpu] == 1) {
+ 		/* A power_up request went ahead of us. */
+-		spin_unlock(&boot_lock);
++		raw_spin_unlock(&boot_lock);
+ 		return;
+ 	} else if (hip04_cpu_table[cluster][cpu] > 1) {
+ 		pr_err("Cluster %d CPU%d boots multiple times\n", cluster, cpu);
+@@ -174,7 +174,7 @@ static void hip04_cpu_die(unsigned int l_cpu)
+ 	}
+ 
+ 	last_man = hip04_cluster_is_down(cluster);
+-	spin_unlock(&boot_lock);
++	raw_spin_unlock(&boot_lock);
+ 	if (last_man) {
+ 		/* Since it's Cortex A15, disable L2 prefetching. */
+ 		asm volatile(
+@@ -203,7 +203,7 @@ static int hip04_cpu_kill(unsigned int l_cpu)
+ 	       cpu >= HIP04_MAX_CPUS_PER_CLUSTER);
+ 
+ 	count = TIMEOUT_MSEC / POLL_MSEC;
+-	spin_lock_irq(&boot_lock);
++	raw_spin_lock_irq(&boot_lock);
+ 	for (tries = 0; tries < count; tries++) {
+ 		if (hip04_cpu_table[cluster][cpu])
+ 			goto err;
+@@ -211,10 +211,10 @@ static int hip04_cpu_kill(unsigned int l_cpu)
+ 		data = readl_relaxed(sysctrl + SC_CPU_RESET_STATUS(cluster));
+ 		if (data & CORE_WFI_STATUS(cpu))
+ 			break;
+-		spin_unlock_irq(&boot_lock);
++		raw_spin_unlock_irq(&boot_lock);
+ 		/* Wait for clean L2 when the whole cluster is down. */
+ 		msleep(POLL_MSEC);
+-		spin_lock_irq(&boot_lock);
++		raw_spin_lock_irq(&boot_lock);
+ 	}
+ 	if (tries >= count)
+ 		goto err;
+@@ -231,10 +231,10 @@ static int hip04_cpu_kill(unsigned int l_cpu)
+ 		goto err;
+ 	if (hip04_cluster_is_down(cluster))
+ 		hip04_set_snoop_filter(cluster, 0);
+-	spin_unlock_irq(&boot_lock);
++	raw_spin_unlock_irq(&boot_lock);
+ 	return 1;
+ err:
+-	spin_unlock_irq(&boot_lock);
++	raw_spin_unlock_irq(&boot_lock);
+ 	return 0;
+ }
+ #endif
+diff --git a/arch/arm/mach-imx/Kconfig b/arch/arm/mach-imx/Kconfig
+index 8973fae25436..dd905b9602a0 100644
+--- a/arch/arm/mach-imx/Kconfig
++++ b/arch/arm/mach-imx/Kconfig
+@@ -526,7 +526,7 @@ config SOC_IMX6Q
+ 	bool "i.MX6 Quad/DualLite support"
+ 	select ARM_ERRATA_764369 if SMP
+ 	select HAVE_ARM_SCU if SMP
+-	select HAVE_ARM_TWD if SMP
++	select HAVE_ARM_TWD
+ 	select PCI_DOMAINS if PCI
+ 	select PINCTRL_IMX6Q
+ 	select SOC_IMX6
+diff --git a/arch/arm/mach-omap2/omap-smp.c b/arch/arm/mach-omap2/omap-smp.c
+index c625cc10d9f9..6cbad704cc3d 100644
+--- a/arch/arm/mach-omap2/omap-smp.c
++++ b/arch/arm/mach-omap2/omap-smp.c
+@@ -43,7 +43,7 @@
+ /* 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)
+ {
+@@ -74,8 +74,8 @@ static void omap4_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);
+ }
+ 
+ static int omap4_boot_secondary(unsigned int cpu, struct task_struct *idle)
+@@ -89,7 +89,7 @@ static int omap4_boot_secondary(unsigned int cpu, struct task_struct *idle)
+ 	 * 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.
+@@ -166,7 +166,7 @@ static int omap4_boot_secondary(unsigned int cpu, struct task_struct *idle)
+ 	 * 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;
+ }
+diff --git a/arch/arm/mach-prima2/platsmp.c b/arch/arm/mach-prima2/platsmp.c
+index 0875b99add18..18b6d98d2581 100644
+--- a/arch/arm/mach-prima2/platsmp.c
++++ b/arch/arm/mach-prima2/platsmp.c
+@@ -22,7 +22,7 @@
+ 
+ static void __iomem *clk_base;
+ 
+-static DEFINE_SPINLOCK(boot_lock);
++static DEFINE_RAW_SPINLOCK(boot_lock);
+ 
+ static void sirfsoc_secondary_init(unsigned int cpu)
+ {
+@@ -36,8 +36,8 @@ static void sirfsoc_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);
+ }
+ 
+ static const struct of_device_id clk_ids[]  = {
+@@ -75,7 +75,7 @@ static int sirfsoc_boot_secondary(unsigned int cpu, struct task_struct *idle)
+ 	/* 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
+@@ -107,7 +107,7 @@ static int sirfsoc_boot_secondary(unsigned int cpu, struct task_struct *idle)
+ 	 * 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;
+ }
+diff --git a/arch/arm/mach-qcom/platsmp.c b/arch/arm/mach-qcom/platsmp.c
+index 5494c9e0c909..e8ce157d3548 100644
+--- a/arch/arm/mach-qcom/platsmp.c
++++ b/arch/arm/mach-qcom/platsmp.c
+@@ -46,7 +46,7 @@
+ 
+ extern void secondary_startup_arm(void);
+ 
+-static DEFINE_SPINLOCK(boot_lock);
++static DEFINE_RAW_SPINLOCK(boot_lock);
+ 
+ #ifdef CONFIG_HOTPLUG_CPU
+ static void qcom_cpu_die(unsigned int cpu)
+@@ -60,8 +60,8 @@ static void qcom_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);
+ }
+ 
+ static int scss_release_secondary(unsigned int cpu)
+@@ -284,7 +284,7 @@ static int qcom_boot_secondary(unsigned int cpu, int (*func)(unsigned int))
+ 	 * set synchronisation state between this boot processor
+ 	 * and the secondary one
+ 	 */
+-	spin_lock(&boot_lock);
++	raw_spin_lock(&boot_lock);
+ 
+ 	/*
+ 	 * Send the secondary CPU a soft interrupt, thereby causing
+@@ -297,7 +297,7 @@ static int qcom_boot_secondary(unsigned int cpu, int (*func)(unsigned int))
+ 	 * 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 ret;
+ }
+diff --git a/arch/arm/mach-spear/platsmp.c b/arch/arm/mach-spear/platsmp.c
+index 8d1e2d551786..7fa56cc78118 100644
+--- a/arch/arm/mach-spear/platsmp.c
++++ b/arch/arm/mach-spear/platsmp.c
+@@ -32,7 +32,7 @@ static void write_pen_release(int val)
+ 	sync_cache_w(&pen_release);
+ }
+ 
+-static DEFINE_SPINLOCK(boot_lock);
++static DEFINE_RAW_SPINLOCK(boot_lock);
+ 
+ static void __iomem *scu_base = IOMEM(VA_SCU_BASE);
+ 
+@@ -47,8 +47,8 @@ static void spear13xx_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);
+ }
+ 
+ static int spear13xx_boot_secondary(unsigned int cpu, struct task_struct *idle)
+@@ -59,7 +59,7 @@ static int spear13xx_boot_secondary(unsigned int cpu, struct task_struct *idle)
+ 	 * 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
+@@ -84,7 +84,7 @@ static int spear13xx_boot_secondary(unsigned int cpu, struct task_struct *idle)
+ 	 * 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;
+ }
+diff --git a/arch/arm/mach-sti/platsmp.c b/arch/arm/mach-sti/platsmp.c
+index ea5a2277ee46..b988e081ac79 100644
+--- a/arch/arm/mach-sti/platsmp.c
++++ b/arch/arm/mach-sti/platsmp.c
+@@ -35,7 +35,7 @@ static void write_pen_release(int val)
+ 	sync_cache_w(&pen_release);
+ }
+ 
+-static DEFINE_SPINLOCK(boot_lock);
++static DEFINE_RAW_SPINLOCK(boot_lock);
+ 
+ static void sti_secondary_init(unsigned int cpu)
+ {
+@@ -48,8 +48,8 @@ static 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);
+ }
+ 
+ static int sti_boot_secondary(unsigned int cpu, struct task_struct *idle)
+@@ -60,7 +60,7 @@ static int sti_boot_secondary(unsigned int cpu, struct task_struct *idle)
+ 	 * 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
+@@ -91,7 +91,7 @@ static int sti_boot_secondary(unsigned int cpu, struct task_struct *idle)
+ 	 * 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;
+ }
+diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
+index ad5841856007..7678f0616a0a 100644
+--- a/arch/arm/mm/fault.c
++++ b/arch/arm/mm/fault.c
+@@ -430,6 +430,9 @@ do_translation_fault(unsigned long addr, unsigned int fsr,
+ 	if (addr < TASK_SIZE)
+ 		return do_page_fault(addr, fsr, regs);
+ 
++	if (interrupts_enabled(regs))
++		local_irq_enable();
++
+ 	if (user_mode(regs))
+ 		goto bad_area;
+ 
+@@ -497,6 +500,9 @@ do_translation_fault(unsigned long addr, unsigned int fsr,
+ static int
+ do_sect_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
+ {
++	if (interrupts_enabled(regs))
++		local_irq_enable();
++
+ 	do_bad_area(addr, fsr, regs);
+ 	return 0;
+ }
+diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c
+index d02f8187b1cc..542692dbd40a 100644
+--- a/arch/arm/mm/highmem.c
++++ b/arch/arm/mm/highmem.c
+@@ -34,6 +34,11 @@ static inline pte_t get_fixmap_pte(unsigned long vaddr)
+ 	return *ptep;
+ }
+ 
++static unsigned int fixmap_idx(int type)
++{
++	return FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
++}
++
+ void *kmap(struct page *page)
+ {
+ 	might_sleep();
+@@ -54,12 +59,13 @@ 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;
+ 	int type;
+ 
+-	preempt_disable();
++	preempt_disable_nort();
+ 	pagefault_disable();
+ 	if (!PageHighMem(page))
+ 		return page_address(page);
+@@ -79,7 +85,7 @@ void *kmap_atomic(struct page *page)
+ 
+ 	type = kmap_atomic_idx_push();
+ 
+-	idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
++	idx = fixmap_idx(type);
+ 	vaddr = __fix_to_virt(idx);
+ #ifdef CONFIG_DEBUG_HIGHMEM
+ 	/*
+@@ -93,7 +99,10 @@ void *kmap_atomic(struct page *page)
+ 	 * in place, so the contained TLB flush ensures the TLB is updated
+ 	 * with the new mapping.
+ 	 */
+-	set_fixmap_pte(idx, mk_pte(page, kmap_prot));
++#ifdef CONFIG_PREEMPT_RT_FULL
++	current->kmap_pte[type] = pte;
++#endif
++	set_fixmap_pte(idx, pte);
+ 
+ 	return (void *)vaddr;
+ }
+@@ -106,44 +115,75 @@ void __kunmap_atomic(void *kvaddr)
+ 
+ 	if (kvaddr >= (void *)FIXADDR_START) {
+ 		type = kmap_atomic_idx();
+-		idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
++		idx = fixmap_idx(type);
+ 
+ 		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(idx));
+-		set_fixmap_pte(idx, __pte(0));
+ #else
+ 		(void) idx;  /* to kill a warning */
+ #endif
++		set_fixmap_pte(idx, __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() */
+ 		kunmap_high(pte_page(pkmap_page_table[PKMAP_NR(vaddr)]));
+ 	}
+ 	pagefault_enable();
+-	preempt_enable();
++	preempt_enable_nort();
+ }
+ 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;
+ 	struct page *page = pfn_to_page(pfn);
+ 
+-	preempt_disable();
++	preempt_disable_nort();
+ 	pagefault_disable();
+ 	if (!PageHighMem(page))
+ 		return page_address(page);
+ 
+ 	type = kmap_atomic_idx_push();
+-	idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
++	idx = fixmap_idx(type);
+ 	vaddr = __fix_to_virt(idx);
+ #ifdef CONFIG_DEBUG_HIGHMEM
+ 	BUG_ON(!pte_none(get_fixmap_pte(vaddr)));
+ #endif
+-	set_fixmap_pte(idx, pfn_pte(pfn, kmap_prot));
++#ifdef CONFIG_PREEMPT_RT_FULL
++	current->kmap_pte[type] = pte;
++#endif
++	set_fixmap_pte(idx, pte);
+ 
+ 	return (void *)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 = fixmap_idx(i);
++
++		set_fixmap_pte(idx, __pte(0));
++	}
++	/*
++	 * Restore @next_p's kmap_atomic mappings
++	 */
++	for (i = 0; i < next_p->kmap_idx; i++) {
++		int idx = fixmap_idx(i);
++
++		if (!pte_none(next_p->kmap_pte[i]))
++			set_fixmap_pte(idx, next_p->kmap_pte[i]);
++	}
++}
++#endif
+diff --git a/arch/arm/plat-versatile/platsmp.c b/arch/arm/plat-versatile/platsmp.c
+index 53feb90c840c..b4a8d54fc3f3 100644
+--- a/arch/arm/plat-versatile/platsmp.c
++++ b/arch/arm/plat-versatile/platsmp.c
+@@ -30,7 +30,7 @@ static void write_pen_release(int val)
+ 	sync_cache_w(&pen_release);
+ }
+ 
+-static DEFINE_SPINLOCK(boot_lock);
++static DEFINE_RAW_SPINLOCK(boot_lock);
+ 
+ void versatile_secondary_init(unsigned int cpu)
+ {
+@@ -43,8 +43,8 @@ void versatile_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 versatile_boot_secondary(unsigned int cpu, struct task_struct *idle)
+@@ -55,7 +55,7 @@ int versatile_boot_secondary(unsigned int cpu, struct task_struct *idle)
+ 	 * 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
+@@ -85,7 +85,7 @@ int versatile_boot_secondary(unsigned int cpu, struct task_struct *idle)
+ 	 * 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;
+ }
+diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
+index 4f436220384f..0d7f54cebae3 100644
+--- a/arch/arm64/Kconfig
++++ b/arch/arm64/Kconfig
+@@ -81,6 +81,7 @@ config ARM64
+ 	select HAVE_PERF_REGS
+ 	select HAVE_PERF_USER_STACK_DUMP
+ 	select HAVE_RCU_TABLE_FREE
++	select HAVE_PREEMPT_LAZY
+ 	select HAVE_SYSCALL_TRACEPOINTS
+ 	select IOMMU_DMA if IOMMU_SUPPORT
+ 	select IRQ_DOMAIN
+@@ -624,7 +625,7 @@ config XEN_DOM0
+ 
+ config XEN
+ 	bool "Xen guest support on ARM64"
+-	depends on ARM64 && OF
++	depends on ARM64 && OF && !PREEMPT_RT_FULL
+ 	select SWIOTLB_XEN
+ 	select PARAVIRT
+ 	help
+diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h
+index abd64bd1f6d9..9170788ffa37 100644
+--- a/arch/arm64/include/asm/thread_info.h
++++ b/arch/arm64/include/asm/thread_info.h
+@@ -49,6 +49,7 @@ struct thread_info {
+ 	mm_segment_t		addr_limit;	/* address limit */
+ 	struct task_struct	*task;		/* main task structure */
+ 	int			preempt_count;	/* 0 => preemptable, <0 => bug */
++	int			preempt_lazy_count; /* 0 => preemptable, <0 => bug */
+ 	int			cpu;		/* cpu */
+ };
+ 
+@@ -109,6 +110,7 @@ static inline struct thread_info *current_thread_info(void)
+ #define TIF_NEED_RESCHED	1
+ #define TIF_NOTIFY_RESUME	2	/* callback before returning to user */
+ #define TIF_FOREIGN_FPSTATE	3	/* CPU's FP state is not current's */
++#define TIF_NEED_RESCHED_LAZY	4
+ #define TIF_NOHZ		7
+ #define TIF_SYSCALL_TRACE	8
+ #define TIF_SYSCALL_AUDIT	9
+@@ -124,6 +126,7 @@ static inline struct thread_info *current_thread_info(void)
+ #define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
+ #define _TIF_NOTIFY_RESUME	(1 << TIF_NOTIFY_RESUME)
+ #define _TIF_FOREIGN_FPSTATE	(1 << TIF_FOREIGN_FPSTATE)
++#define _TIF_NEED_RESCHED_LAZY	(1 << TIF_NEED_RESCHED_LAZY)
+ #define _TIF_NOHZ		(1 << TIF_NOHZ)
+ #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
+ #define _TIF_SYSCALL_AUDIT	(1 << TIF_SYSCALL_AUDIT)
+@@ -132,7 +135,8 @@ static inline struct thread_info *current_thread_info(void)
+ #define _TIF_32BIT		(1 << TIF_32BIT)
+ 
+ #define _TIF_WORK_MASK		(_TIF_NEED_RESCHED | _TIF_SIGPENDING | \
+-				 _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE)
++				 _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE | \
++				 _TIF_NEED_RESCHED_LAZY)
+ 
+ #define _TIF_SYSCALL_WORK	(_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
+ 				 _TIF_SYSCALL_TRACEPOINT | _TIF_SECCOMP | \
+diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c
+index 1abcd8829f3b..8290a50d6dd3 100644
+--- a/arch/arm64/kernel/asm-offsets.c
++++ b/arch/arm64/kernel/asm-offsets.c
+@@ -36,6 +36,7 @@ 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_CPU,		offsetof(struct thread_info, cpu));
+diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
+index 6c3b7345a6c4..d4ec679f7e1f 100644
+--- a/arch/arm64/kernel/entry.S
++++ b/arch/arm64/kernel/entry.S
+@@ -426,11 +426,16 @@ ENDPROC(el1_sync)
+ 
+ #ifdef CONFIG_PREEMPT
+ 	ldr	w24, [tsk, #TI_PREEMPT]		// get preempt count
+-	cbnz	w24, 1f				// preempt count != 0
++	cbnz	w24, 2f				// preempt count != 0
+ 	ldr	x0, [tsk, #TI_FLAGS]		// get flags
+-	tbz	x0, #TIF_NEED_RESCHED, 1f	// needs rescheduling?
+-	bl	el1_preempt
++	tbnz	x0, #TIF_NEED_RESCHED, 1f	// needs rescheduling?
++
++	ldr	w24, [tsk, #TI_PREEMPT_LAZY]	// get preempt lazy count
++	cbnz	w24, 2f				// preempt lazy count != 0
++	tbz	x0, #TIF_NEED_RESCHED_LAZY, 2f	// needs rescheduling?
+ 1:
++	bl	el1_preempt
++2:
+ #endif
+ #ifdef CONFIG_TRACE_IRQFLAGS
+ 	bl	trace_hardirqs_on
+@@ -444,6 +449,7 @@ ENDPROC(el1_irq)
+ 1:	bl	preempt_schedule_irq		// irq en/disable is done inside
+ 	ldr	x0, [tsk, #TI_FLAGS]		// get new tasks TI_FLAGS
+ 	tbnz	x0, #TIF_NEED_RESCHED, 1b	// needs rescheduling?
++	tbnz	x0, #TIF_NEED_RESCHED_LAZY, 1b	// needs rescheduling?
+ 	ret	x24
+ #endif
+ 
+@@ -690,6 +696,7 @@ ENDPROC(cpu_switch_to)
+  */
+ work_pending:
+ 	tbnz	x1, #TIF_NEED_RESCHED, work_resched
++	tbnz	x1, #TIF_NEED_RESCHED_LAZY, work_resched
+ 	/* TIF_SIGPENDING, TIF_NOTIFY_RESUME or TIF_FOREIGN_FPSTATE case */
+ 	mov	x0, sp				// 'regs'
+ 	enable_irq				// enable interrupts for do_notify_resume()
+diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
+index 2018c2b0e078..3f3820fdb80e 100644
+--- a/arch/mips/Kconfig
++++ b/arch/mips/Kconfig
+@@ -2416,7 +2416,7 @@ config CPU_R4400_WORKAROUNDS
+ #
+ config HIGHMEM
+ 	bool "High Memory Support"
+-	depends on 32BIT && CPU_SUPPORTS_HIGHMEM && SYS_SUPPORTS_HIGHMEM && !CPU_MIPS32_3_5_EVA
++	depends on 32BIT && CPU_SUPPORTS_HIGHMEM && SYS_SUPPORTS_HIGHMEM && !CPU_MIPS32_3_5_EVA && !PREEMPT_RT_FULL
+ 
+ config CPU_SUPPORTS_HIGHMEM
+ 	bool
+diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
+index 7cd32c038286..69c3f4db485b 100644
+--- a/arch/powerpc/Kconfig
++++ b/arch/powerpc/Kconfig
+@@ -57,10 +57,11 @@ 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
+@@ -138,6 +139,7 @@ config PPC
+ 	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
+ 	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
+@@ -319,7 +321,7 @@ 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
+diff --git a/arch/powerpc/include/asm/thread_info.h b/arch/powerpc/include/asm/thread_info.h
+index 7efee4a3240b..40e6fa1b85b2 100644
+--- a/arch/powerpc/include/asm/thread_info.h
++++ b/arch/powerpc/include/asm/thread_info.h
+@@ -42,6 +42,8 @@ struct thread_info {
+ 	int		cpu;			/* cpu we're on */
+ 	int		preempt_count;		/* 0 => preemptable,
+ 						   <0 => BUG */
++	int		preempt_lazy_count;	 /* 0 => preemptable,
++						   <0 => BUG */
+ 	unsigned long	local_flags;		/* private flags for thread */
+ 
+ 	/* low level flags - has atomic operations done on it */
+@@ -82,8 +84,7 @@ static inline struct thread_info *current_thread_info(void)
+ #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_RESTORE_TM		5	/* need to restore TM FP/VEC/VSX */
+ #define TIF_SYSCALL_AUDIT	7	/* syscall auditing active */
+@@ -101,6 +102,8 @@ static inline struct thread_info *current_thread_info(void)
+ #if defined(CONFIG_PPC64)
+ #define TIF_ELF2ABI		18	/* function descriptors must die! */
+ #endif
++#define TIF_POLLING_NRFLAG	19	/* true if poll_idle() is polling
++					   TIF_NEED_RESCHED */
+ 
+ /* as above, but as bit values */
+ #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
+@@ -119,14 +122,16 @@ static inline struct thread_info *current_thread_info(void)
+ #define _TIF_SYSCALL_TRACEPOINT	(1<<TIF_SYSCALL_TRACEPOINT)
+ #define _TIF_EMULATE_STACK_STORE	(1<<TIF_EMULATE_STACK_STORE)
+ #define _TIF_NOHZ		(1<<TIF_NOHZ)
++#define _TIF_NEED_RESCHED_LAZY	(1<<TIF_NEED_RESCHED_LAZY)
+ #define _TIF_SYSCALL_DOTRACE	(_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_RESTORE_TM)
++				 _TIF_RESTORE_TM | _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 */
+diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
+index 0d0183d3180a..476cf176816b 100644
+--- a/arch/powerpc/kernel/asm-offsets.c
++++ b/arch/powerpc/kernel/asm-offsets.c
+@@ -162,6 +162,7 @@ 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));
+ 
+diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
+index 2405631e91a2..c21b4b42eaa0 100644
+--- a/arch/powerpc/kernel/entry_32.S
++++ b/arch/powerpc/kernel/entry_32.S
+@@ -818,7 +818,14 @@ user_exc_return:		/* r10 contains MSR_KERNEL here */
+ 	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 */
+@@ -829,11 +836,11 @@ user_exc_return:		/* r10 contains MSR_KERNEL here */
+ 	 */
+ 	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
+@@ -1154,7 +1161,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_NEED_PAIRED_STWCX)
+ #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 */
+@@ -1175,7 +1182,7 @@ do_resched:			/* r10 contains MSR_KERNEL here */
+ 	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
+diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
+index 9916d150b28c..5dce9354223c 100644
+--- a/arch/powerpc/kernel/entry_64.S
++++ b/arch/powerpc/kernel/entry_64.S
+@@ -644,7 +644,7 @@ _GLOBAL(ret_from_except_lite)
+ 	bl	restore_math
+ 	b	restore
+ #endif
+-1:	andi.	r0,r4,_TIF_NEED_RESCHED
++1:	andi.	r0,r4,_TIF_NEED_RESCHED_MASK
+ 	beq	2f
+ 	bl	restore_interrupts
+ 	SCHEDULE_USER
+@@ -706,10 +706,18 @@ _GLOBAL(ret_from_except_lite)
+ 
+ #ifdef CONFIG_PREEMPT
+ 	/* Check if we need to preempt */
+-	andi.	r0,r4,_TIF_NEED_RESCHED
+-	beq+	restore
+-	/* Check that preempt_count() == 0 and interrupts are enabled */
+ 	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 */
++check_count:
+ 	cmpwi	cr1,r8,0
+ 	ld	r0,SOFTE(r1)
+ 	cmpdi	r0,0
+@@ -726,7 +734,7 @@ _GLOBAL(ret_from_except_lite)
+ 	/* 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
+ 
+ 	/*
+diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
+index 290559df1e8b..070afa6da35d 100644
+--- a/arch/powerpc/kernel/irq.c
++++ b/arch/powerpc/kernel/irq.c
+@@ -614,6 +614,7 @@ void irq_ctx_init(void)
+ 	}
+ }
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
+ void do_softirq_own_stack(void)
+ {
+ 	struct thread_info *curtp, *irqtp;
+@@ -631,6 +632,7 @@ void do_softirq_own_stack(void)
+ 	if (irqtp->flags)
+ 		set_bits(irqtp->flags, &curtp->flags);
+ }
++#endif
+ 
+ irq_hw_number_t virq_to_hw(unsigned int virq)
+ {
+diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S
+index bf5160fbf9d8..e551d78c8038 100644
+--- a/arch/powerpc/kernel/misc_32.S
++++ b/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);
+diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S
+index f28754c497e5..31ae513acac9 100644
+--- a/arch/powerpc/kernel/misc_64.S
++++ b/arch/powerpc/kernel/misc_64.S
+@@ -30,6 +30,7 @@
+ 
+ 	.text
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
+ _GLOBAL(call_do_softirq)
+ 	mflr	r0
+ 	std	r0,16(r1)
+@@ -40,6 +41,7 @@ _GLOBAL(call_do_softirq)
+ 	ld	r0,16(r1)
+ 	mtlr	r0
+ 	blr
++#endif
+ 
+ _GLOBAL(call_do_irq)
+ 	mflr	r0
+diff --git a/arch/powerpc/kvm/Kconfig b/arch/powerpc/kvm/Kconfig
+index c2024ac9d4e8..2303788da7e1 100644
+--- a/arch/powerpc/kvm/Kconfig
++++ b/arch/powerpc/kvm/Kconfig
+@@ -172,6 +172,7 @@ config KVM_E500MC
+ config KVM_MPIC
+ 	bool "KVM in-kernel MPIC emulation"
+ 	depends on KVM && E500
++	depends on !PREEMPT_RT_FULL
+ 	select HAVE_KVM_IRQCHIP
+ 	select HAVE_KVM_IRQFD
+ 	select HAVE_KVM_IRQ_ROUTING
+diff --git a/arch/powerpc/platforms/ps3/device-init.c b/arch/powerpc/platforms/ps3/device-init.c
+index 3f175e8aedb4..c4c02f91904c 100644
+--- a/arch/powerpc/platforms/ps3/device-init.c
++++ b/arch/powerpc/platforms/ps3/device-init.c
+@@ -752,7 +752,7 @@ static int ps3_notification_read_write(struct ps3_notification_device *dev,
+ 	}
+ 	pr_debug("%s:%u: notification %s issued\n", __func__, __LINE__, op);
+ 
+-	res = wait_event_interruptible(dev->done.wait,
++	res = swait_event_interruptible(dev->done.wait,
+ 				       dev->done.done || kthread_should_stop());
+ 	if (kthread_should_stop())
+ 		res = -EINTR;
+diff --git a/arch/sh/kernel/irq.c b/arch/sh/kernel/irq.c
+index 6c0378c0b8b5..abd58b4dff97 100644
+--- a/arch/sh/kernel/irq.c
++++ b/arch/sh/kernel/irq.c
+@@ -147,6 +147,7 @@ void irq_ctx_exit(int cpu)
+ 	hardirq_ctx[cpu] = NULL;
+ }
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
+ void do_softirq_own_stack(void)
+ {
+ 	struct thread_info *curctx;
+@@ -174,6 +175,7 @@ void do_softirq_own_stack(void)
+ 		  "r5", "r6", "r7", "r8", "r9", "r15", "t", "pr"
+ 	);
+ }
++#endif
+ #else
+ static inline void handle_one_irq(unsigned int irq)
+ {
+diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
+index 57ffaf285c2f..733c72826f28 100644
+--- a/arch/sparc/Kconfig
++++ b/arch/sparc/Kconfig
+@@ -184,12 +184,10 @@ 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
+diff --git a/arch/sparc/kernel/irq_64.c b/arch/sparc/kernel/irq_64.c
+index e22416ce56ea..d359de71153a 100644
+--- a/arch/sparc/kernel/irq_64.c
++++ b/arch/sparc/kernel/irq_64.c
+@@ -854,6 +854,7 @@ void __irq_entry handler_irq(int pil, struct pt_regs *regs)
+ 	set_irq_regs(old_regs);
+ }
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
+ void do_softirq_own_stack(void)
+ {
+ 	void *orig_sp, *sp = softirq_stack[smp_processor_id()];
+@@ -868,6 +869,7 @@ void do_softirq_own_stack(void)
+ 	__asm__ __volatile__("mov %0, %%sp"
+ 			     : : "r" (orig_sp));
+ }
++#endif
+ 
+ #ifdef CONFIG_HOTPLUG_CPU
+ void fixup_irqs(void)
+diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
+index 2dc18605831f..ea65dc777a77 100644
+--- a/arch/x86/Kconfig
++++ b/arch/x86/Kconfig
+@@ -17,6 +17,7 @@ config X86_64
+ ### Arch settings
+ config X86
+ 	def_bool y
++	select HAVE_PREEMPT_LAZY
+ 	select ACPI_LEGACY_TABLES_LOOKUP	if ACPI
+ 	select ACPI_SYSTEM_POWER_STATES_SUPPORT	if ACPI
+ 	select ANON_INODES
+@@ -230,8 +231,11 @@ 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
+@@ -889,7 +893,7 @@ 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.
+diff --git a/arch/x86/crypto/aesni-intel_glue.c b/arch/x86/crypto/aesni-intel_glue.c
+index 064c7e2bd7c8..e400dd3947db 100644
+--- a/arch/x86/crypto/aesni-intel_glue.c
++++ b/arch/x86/crypto/aesni-intel_glue.c
+@@ -383,14 +383,14 @@ static int ecb_encrypt(struct blkcipher_desc *desc,
+ 	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;
+ }
+@@ -407,14 +407,14 @@ static int ecb_decrypt(struct blkcipher_desc *desc,
+ 	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;
+ }
+@@ -431,14 +431,14 @@ static int cbc_encrypt(struct blkcipher_desc *desc,
+ 	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;
+ }
+@@ -455,14 +455,14 @@ static int cbc_decrypt(struct blkcipher_desc *desc,
+ 	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;
+ }
+@@ -514,18 +514,20 @@ static int ctr_crypt(struct blkcipher_desc *desc,
+ 	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_tfm(ctx, walk.dst.virt.addr, walk.src.virt.addr,
+ 			              nbytes & AES_BLOCK_MASK, walk.iv);
++		kernel_fpu_end();
+ 		nbytes &= AES_BLOCK_SIZE - 1;
+ 		err = 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;
+ }
+diff --git a/arch/x86/crypto/cast5_avx_glue.c b/arch/x86/crypto/cast5_avx_glue.c
+index 8648158f3916..d7699130ee36 100644
+--- a/arch/x86/crypto/cast5_avx_glue.c
++++ b/arch/x86/crypto/cast5_avx_glue.c
+@@ -59,7 +59,7 @@ static inline void cast5_fpu_end(bool fpu_enabled)
+ 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;
+@@ -75,7 +75,7 @@ static int ecb_crypt(struct blkcipher_desc *desc, struct blkcipher_walk *walk,
+ 		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) {
+@@ -103,10 +103,9 @@ static int ecb_crypt(struct blkcipher_desc *desc, struct blkcipher_walk *walk,
+ 		} while (nbytes >= bsize);
+ 
+ done:
++		cast5_fpu_end(fpu_enabled);
+ 		err = blkcipher_walk_done(desc, walk, nbytes);
+ 	}
+-
+-	cast5_fpu_end(fpu_enabled);
+ 	return err;
+ }
+ 
+@@ -227,7 +226,7 @@ static unsigned int __cbc_decrypt(struct blkcipher_desc *desc,
+ 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;
+ 
+@@ -236,12 +235,11 @@ static int cbc_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
+ 	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;
+ }
+ 
+@@ -311,7 +309,7 @@ static unsigned int __ctr_crypt(struct blkcipher_desc *desc,
+ 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;
+ 
+@@ -320,13 +318,12 @@ static int ctr_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
+ 	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);
+diff --git a/arch/x86/crypto/glue_helper.c b/arch/x86/crypto/glue_helper.c
+index 6a85598931b5..3a506ce7ed93 100644
+--- a/arch/x86/crypto/glue_helper.c
++++ b/arch/x86/crypto/glue_helper.c
+@@ -39,7 +39,7 @@ static int __glue_ecb_crypt_128bit(const struct common_glue_ctx *gctx,
+ 	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 struct common_glue_ctx *gctx,
+ 		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 struct common_glue_ctx *gctx,
+ 		}
+ 
+ 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 common_glue_ctx *gctx,
+ 			    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 common_glue_ctx *gctx,
+ 
+ 	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);
+@@ -277,7 +277,7 @@ int glue_ctr_crypt_128bit(const struct common_glue_ctx *gctx,
+ 			  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;
+ 
+@@ -286,13 +286,12 @@ int glue_ctr_crypt_128bit(const struct common_glue_ctx *gctx,
+ 
+ 	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);
+@@ -347,7 +346,7 @@ int glue_xts_crypt_128bit(const struct common_glue_ctx *gctx,
+ 			  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;
+ 
+@@ -360,21 +359,21 @@ int glue_xts_crypt_128bit(const struct common_glue_ctx *gctx,
+ 
+ 	/* 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);
+diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c
+index e79d93d44ecd..ef2564dc2656 100644
+--- a/arch/x86/entry/common.c
++++ b/arch/x86/entry/common.c
+@@ -202,7 +202,7 @@ long syscall_trace_enter(struct pt_regs *regs)
+ 
+ #define EXIT_TO_USERMODE_LOOP_FLAGS				\
+ 	(_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_UPROBE |	\
+-	 _TIF_NEED_RESCHED | _TIF_USER_RETURN_NOTIFY)
++	 _TIF_NEED_RESCHED_MASK | _TIF_USER_RETURN_NOTIFY)
+ 
+ static void exit_to_usermode_loop(struct pt_regs *regs, u32 cached_flags)
+ {
+@@ -218,9 +218,16 @@ static void exit_to_usermode_loop(struct pt_regs *regs, u32 cached_flags)
+ 		/* We have work to do. */
+ 		local_irq_enable();
+ 
+-		if (cached_flags & _TIF_NEED_RESCHED)
++		if (cached_flags & _TIF_NEED_RESCHED_MASK)
+ 			schedule();
+ 
++#ifdef ARCH_RT_DELAYS_SIGNAL_SEND
++		if (unlikely(current->forced_info.si_signo)) {
++			struct task_struct *t = current;
++			force_sig_info(t->forced_info.si_signo, &t->forced_info, t);
++			t->forced_info.si_signo = 0;
++		}
++#endif
+ 		if (cached_flags & _TIF_UPROBE)
+ 			uprobe_notify_resume(regs);
+ 
+diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S
+index 10868aa734dc..7c7d3085f046 100644
+--- a/arch/x86/entry/entry_32.S
++++ b/arch/x86/entry/entry_32.S
+@@ -278,8 +278,24 @@ END(ret_from_exception)
+ ENTRY(resume_kernel)
+ 	DISABLE_INTERRUPTS(CLBR_ANY)
+ need_resched:
++	# preempt count == 0 + NEED_RS set?
+ 	cmpl	$0, PER_CPU_VAR(__preempt_count)
++#ifndef CONFIG_PREEMPT_LAZY
+ 	jnz	restore_all
++#else
++	jz test_int_off
++
++	# atleast preempt count == 0 ?
++	cmpl $_PREEMPT_ENABLED,PER_CPU_VAR(__preempt_count)
++	jne restore_all
++
++	cmpl $0,TI_preempt_lazy_count(%ebp)	# non-zero preempt_lazy_count ?
++	jnz restore_all
++
++	testl $_TIF_NEED_RESCHED_LAZY, TI_flags(%ebp)
++	jz restore_all
++test_int_off:
++#endif
+ 	testl	$X86_EFLAGS_IF, PT_EFLAGS(%esp)	# interrupts off (exception path) ?
+ 	jz	restore_all
+ 	call	preempt_schedule_irq
+diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
+index 858b555e274b..a93639ddfbf6 100644
+--- a/arch/x86/entry/entry_64.S
++++ b/arch/x86/entry/entry_64.S
+@@ -511,7 +511,23 @@ GLOBAL(retint_user)
+ 	bt	$9, EFLAGS(%rsp)		/* were interrupts off? */
+ 	jnc	1f
+ 0:	cmpl	$0, PER_CPU_VAR(__preempt_count)
++#ifndef CONFIG_PREEMPT_LAZY
+ 	jnz	1f
++#else
++	jz	do_preempt_schedule_irq
++
++	# atleast preempt count == 0 ?
++	cmpl $_PREEMPT_ENABLED,PER_CPU_VAR(__preempt_count)
++	jnz	1f
++
++	GET_THREAD_INFO(%rcx)
++	cmpl	$0, TI_preempt_lazy_count(%rcx)
++	jnz	1f
++
++	bt	$TIF_NEED_RESCHED_LAZY,TI_flags(%rcx)
++	jnc	1f
++do_preempt_schedule_irq:
++#endif
+ 	call	preempt_schedule_irq
+ 	jmp	0b
+ 1:
+@@ -799,6 +815,7 @@ END(native_load_gs_index)
+ 	jmp	2b
+ 	.previous
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
+ /* Call softirq on interrupt stack. Interrupts are off. */
+ ENTRY(do_softirq_own_stack)
+ 	pushq	%rbp
+@@ -811,6 +828,7 @@ ENTRY(do_softirq_own_stack)
+ 	decl	PER_CPU_VAR(irq_count)
+ 	ret
+ END(do_softirq_own_stack)
++#endif
+ 
+ #ifdef CONFIG_XEN
+ idtentry xen_hypervisor_callback xen_do_hypervisor_callback has_error_code=0
+diff --git a/arch/x86/include/asm/preempt.h b/arch/x86/include/asm/preempt.h
+index d397deb58146..190af4271b5c 100644
+--- a/arch/x86/include/asm/preempt.h
++++ b/arch/x86/include/asm/preempt.h
+@@ -79,17 +79,33 @@ static __always_inline void __preempt_count_sub(int val)
+  * a decrement which hits zero means we have no preempt_count and should
+  * reschedule.
+  */
+-static __always_inline bool __preempt_count_dec_and_test(void)
++static __always_inline bool ____preempt_count_dec_and_test(void)
+ {
+ 	GEN_UNARY_RMWcc("decl", __preempt_count, __percpu_arg(0), "e");
+ }
+ 
++static __always_inline bool __preempt_count_dec_and_test(void)
++{
++	if (____preempt_count_dec_and_test())
++		return true;
++#ifdef CONFIG_PREEMPT_LAZY
++	return test_thread_flag(TIF_NEED_RESCHED_LAZY);
++#else
++	return false;
++#endif
++}
++
+ /*
+  * Returns true when we need to resched and can (barring IRQ state).
+  */
+ static __always_inline bool should_resched(int preempt_offset)
+ {
++#ifdef CONFIG_PREEMPT_LAZY
++	return unlikely(raw_cpu_read_4(__preempt_count) == preempt_offset ||
++			test_thread_flag(TIF_NEED_RESCHED_LAZY));
++#else
+ 	return unlikely(raw_cpu_read_4(__preempt_count) == preempt_offset);
++#endif
+ }
+ 
+ #ifdef CONFIG_PREEMPT
+diff --git a/arch/x86/include/asm/signal.h b/arch/x86/include/asm/signal.h
+index 2138c9ae19ee..3f5b4ee2e2c1 100644
+--- a/arch/x86/include/asm/signal.h
++++ b/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)
++#define ARCH_RT_DELAYS_SIGNAL_SEND
++#endif
++
+ #ifndef CONFIG_COMPAT
+ typedef sigset_t compat_sigset_t;
+ #endif
+diff --git a/arch/x86/include/asm/stackprotector.h b/arch/x86/include/asm/stackprotector.h
+index 58505f01962f..02fa39652cd6 100644
+--- a/arch/x86/include/asm/stackprotector.h
++++ b/arch/x86/include/asm/stackprotector.h
+@@ -59,7 +59,7 @@
+  */
+ static __always_inline void boot_init_stack_canary(void)
+ {
+-	u64 canary;
++	u64 uninitialized_var(canary);
+ 	u64 tsc;
+ 
+ #ifdef CONFIG_X86_64
+@@ -70,8 +70,15 @@ static __always_inline void boot_init_stack_canary(void)
+ 	 * of randomness. The TSC only matters for very early init,
+ 	 * there it already has some randomness on most systems. Later
+ 	 * on during the bootup the random pool has true entropy too.
++	 *
++	 * For preempt-rt we need to weaken the randomness a bit, as
++	 * we can't call into the random generator from atomic context
++	 * due to locking constraints. We just leave canary
++	 * uninitialized and use the TSC based randomness on top of it.
+ 	 */
++#ifndef CONFIG_PREEMPT_RT_FULL
+ 	get_random_bytes(&canary, sizeof(canary));
++#endif
+ 	tsc = rdtsc();
+ 	canary += tsc + (tsc << 32UL);
+ 
+diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h
+index ffae84df8a93..b4575ba19a59 100644
+--- a/arch/x86/include/asm/thread_info.h
++++ b/arch/x86/include/asm/thread_info.h
+@@ -58,6 +58,8 @@ struct thread_info {
+ 	__u32			status;		/* thread synchronous flags */
+ 	__u32			cpu;		/* current CPU */
+ 	mm_segment_t		addr_limit;
++	int			preempt_lazy_count;	/* 0 => lazy preemptable
++							  <0 => BUG */
+ 	unsigned int		sig_on_uaccess_error:1;
+ 	unsigned int		uaccess_err:1;	/* uaccess failed */
+ };
+@@ -95,6 +97,7 @@ 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_USER_RETURN_NOTIFY	11	/* notify kernel of userspace return */
+ #define TIF_UPROBE		12	/* breakpointed or singlestepping */
+ #define TIF_NOTSC		16	/* TSC is not accessible in userland */
+@@ -119,6 +122,7 @@ 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_USER_RETURN_NOTIFY	(1 << TIF_USER_RETURN_NOTIFY)
+ #define _TIF_UPROBE		(1 << TIF_UPROBE)
+ #define _TIF_NOTSC		(1 << TIF_NOTSC)
+@@ -155,6 +159,8 @@ 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 STACK_WARN		(THREAD_SIZE/8)
+ 
+ /*
+diff --git a/arch/x86/include/asm/uv/uv_bau.h b/arch/x86/include/asm/uv/uv_bau.h
+index fc808b83fccb..ebb40118abf5 100644
+--- a/arch/x86/include/asm/uv/uv_bau.h
++++ b/arch/x86/include/asm/uv/uv_bau.h
+@@ -615,9 +615,9 @@ struct bau_control {
+ 	cycles_t		send_message;
+ 	cycles_t		period_end;
+ 	cycles_t		period_time;
+-	spinlock_t		uvhub_lock;
+-	spinlock_t		queue_lock;
+-	spinlock_t		disable_lock;
++	raw_spinlock_t		uvhub_lock;
++	raw_spinlock_t		queue_lock;
++	raw_spinlock_t		disable_lock;
+ 	/* tunables */
+ 	int			max_concurr;
+ 	int			max_concurr_const;
+@@ -776,15 +776,15 @@ static inline int atom_asr(short i, struct atomic_short *v)
+  * to be lowered below the current 'v'.  atomic_add_unless can only stop
+  * on equal.
+  */
+-static inline int atomic_inc_unless_ge(spinlock_t *lock, atomic_t *v, int u)
++static inline int atomic_inc_unless_ge(raw_spinlock_t *lock, atomic_t *v, int u)
+ {
+-	spin_lock(lock);
++	raw_spin_lock(lock);
+ 	if (atomic_read(v) >= u) {
+-		spin_unlock(lock);
++		raw_spin_unlock(lock);
+ 		return 0;
+ 	}
+ 	atomic_inc(v);
+-	spin_unlock(lock);
++	raw_spin_unlock(lock);
+ 	return 1;
+ }
+ 
+diff --git a/arch/x86/include/asm/uv/uv_hub.h b/arch/x86/include/asm/uv/uv_hub.h
+index ea7074784cc4..01ec643ce66e 100644
+--- a/arch/x86/include/asm/uv/uv_hub.h
++++ b/arch/x86/include/asm/uv/uv_hub.h
+@@ -492,7 +492,7 @@ struct uv_blade_info {
+ 	unsigned short	nr_online_cpus;
+ 	unsigned short	pnode;
+ 	short		memory_nid;
+-	spinlock_t	nmi_lock;	/* obsolete, see uv_hub_nmi */
++	raw_spinlock_t	nmi_lock;	/* obsolete, see uv_hub_nmi */
+ 	unsigned long	nmi_count;	/* obsolete, see uv_hub_nmi */
+ };
+ extern struct uv_blade_info *uv_blade_info;
+diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
+index fdb0fbfb1197..678c711e2a16 100644
+--- a/arch/x86/kernel/apic/io_apic.c
++++ b/arch/x86/kernel/apic/io_apic.c
+@@ -1711,7 +1711,8 @@ static bool io_apic_level_ack_pending(struct mp_chip_data *data)
+ static inline bool ioapic_irqd_mask(struct irq_data *data)
+ {
+ 	/* 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_irq(data);
+ 		return true;
+ 	}
+diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c
+index d7ce96a7daca..cd97771f61d6 100644
+--- a/arch/x86/kernel/apic/x2apic_uv_x.c
++++ b/arch/x86/kernel/apic/x2apic_uv_x.c
+@@ -755,7 +755,7 @@ static void uv_heartbeat(unsigned long ignored)
+ 	uv_set_scir_bits(bits);
+ 
+ 	/* enable next timer period */
+-	mod_timer_pinned(timer, jiffies + SCIR_CPU_HB_INTERVAL);
++	mod_timer(timer, jiffies + SCIR_CPU_HB_INTERVAL);
+ }
+ 
+ static void uv_heartbeat_enable(int cpu)
+@@ -764,7 +764,7 @@ static void uv_heartbeat_enable(int cpu)
+ 		struct timer_list *timer = &uv_cpu_hub_info(cpu)->scir.timer;
+ 
+ 		uv_set_cpu_scir_bits(cpu, SCIR_CPU_HEARTBEAT|SCIR_CPU_ACTIVITY);
+-		setup_timer(timer, uv_heartbeat, cpu);
++		setup_pinned_timer(timer, uv_heartbeat, cpu);
+ 		timer->expires = jiffies + SCIR_CPU_HB_INTERVAL;
+ 		add_timer_on(timer, cpu);
+ 		uv_cpu_hub_info(cpu)->scir.enabled = 1;
+@@ -950,7 +950,7 @@ void __init uv_system_init(void)
+ 			uv_blade_info[blade].pnode = pnode;
+ 			uv_blade_info[blade].nr_possible_cpus = 0;
+ 			uv_blade_info[blade].nr_online_cpus = 0;
+-			spin_lock_init(&uv_blade_info[blade].nmi_lock);
++			raw_spin_lock_init(&uv_blade_info[blade].nmi_lock);
+ 			min_pnode = min(pnode, min_pnode);
+ 			max_pnode = max(pnode, max_pnode);
+ 			blade++;
+diff --git a/arch/x86/kernel/asm-offsets.c b/arch/x86/kernel/asm-offsets.c
+index 5c042466f274..ea558b0576d0 100644
+--- a/arch/x86/kernel/asm-offsets.c
++++ b/arch/x86/kernel/asm-offsets.c
+@@ -32,6 +32,7 @@ void common(void) {
+ 	OFFSET(TI_flags, thread_info, flags);
+ 	OFFSET(TI_status, thread_info, status);
+ 	OFFSET(TI_addr_limit, thread_info, addr_limit);
++	OFFSET(TI_preempt_lazy_count, thread_info, preempt_lazy_count);
+ 
+ 	BLANK();
+ 	OFFSET(crypto_tfm_ctx_offset, crypto_tfm, __crt_ctx);
+@@ -85,4 +86,5 @@ void common(void) {
+ 
+ 	BLANK();
+ 	DEFINE(PTREGS_SIZE, sizeof(struct pt_regs));
++	DEFINE(_PREEMPT_ENABLED, PREEMPT_ENABLED);
+ }
+diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
+index f0c921b03e42..f3bd7b8302ef 100644
+--- a/arch/x86/kernel/cpu/mcheck/mce.c
++++ b/arch/x86/kernel/cpu/mcheck/mce.c
+@@ -41,6 +41,8 @@
+ #include <linux/debugfs.h>
+ #include <linux/irq_work.h>
+ #include <linux/export.h>
++#include <linux/jiffies.h>
++#include <linux/swork.h>
+ 
+ #include <asm/processor.h>
+ #include <asm/traps.h>
+@@ -1240,7 +1242,7 @@ void mce_log_therm_throt_event(__u64 status)
+ static unsigned long check_interval = INITIAL_CHECK_INTERVAL;
+ 
+ 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)
+ {
+@@ -1249,32 +1251,18 @@ static unsigned long mce_adjust_timer_default(unsigned long interval)
+ 
+ static unsigned long (*mce_adjust_timer)(unsigned long interval) = mce_adjust_timer_default;
+ 
+-static void __restart_timer(struct timer_list *t, unsigned long interval)
++static enum hrtimer_restart __restart_timer(struct hrtimer *timer, unsigned long interval)
+ {
+-	unsigned long when = jiffies + interval;
+-	unsigned long flags;
+-
+-	local_irq_save(flags);
+-
+-	if (timer_pending(t)) {
+-		if (time_before(when, t->expires))
+-			mod_timer_pinned(t, when);
+-	} else {
+-		t->expires = round_jiffies(when);
+-		add_timer_on(t, smp_processor_id());
+-	}
+-
+-	local_irq_restore(flags);
++	if (!interval)
++		return HRTIMER_NORESTART;
++	hrtimer_forward_now(timer, ns_to_ktime(jiffies_to_nsecs(interval)));
++	return HRTIMER_RESTART;
+ }
+ 
+-static void mce_timer_fn(unsigned long data)
++static enum hrtimer_restart mce_timer_fn(struct hrtimer *timer)
+ {
+-	struct timer_list *t = this_cpu_ptr(&mce_timer);
+-	int cpu = smp_processor_id();
+ 	unsigned long iv;
+ 
+-	WARN_ON(cpu != data);
+-
+ 	iv = __this_cpu_read(mce_next_interval);
+ 
+ 	if (mce_available(this_cpu_ptr(&cpu_info))) {
+@@ -1297,7 +1285,7 @@ static void mce_timer_fn(unsigned long data)
+ 
+ done:
+ 	__this_cpu_write(mce_next_interval, iv);
+-	__restart_timer(t, iv);
++	return __restart_timer(timer, iv);
+ }
+ 
+ /*
+@@ -1305,7 +1293,7 @@ static void mce_timer_fn(unsigned long data)
+  */
+ void mce_timer_kick(unsigned long interval)
+ {
+-	struct timer_list *t = this_cpu_ptr(&mce_timer);
++	struct hrtimer *t = this_cpu_ptr(&mce_timer);
+ 	unsigned long iv = __this_cpu_read(mce_next_interval);
+ 
+ 	__restart_timer(t, interval);
+@@ -1320,7 +1308,7 @@ 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)
+@@ -1330,6 +1318,56 @@ static void mce_do_trigger(struct work_struct *work)
+ 
+ static DECLARE_WORK(mce_trigger_work, mce_do_trigger);
+ 
++static void __mce_notify_work(struct swork_event *event)
++{
++	/* 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
++static bool notify_work_ready __read_mostly;
++static struct swork_event notify_work;
++
++static int mce_notify_work_init(void)
++{
++	int err;
++
++	err = swork_get();
++	if (err)
++		return err;
++
++	INIT_SWORK(&notify_work, __mce_notify_work);
++	notify_work_ready = true;
++	return 0;
++}
++
++static void mce_notify_work(void)
++{
++	if (notify_work_ready)
++		swork_queue(&notify_work);
++}
++#else
++static void mce_notify_work(void)
++{
++	__mce_notify_work(NULL);
++}
++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
+@@ -1337,19 +1375,8 @@ static DECLARE_WORK(mce_trigger_work, mce_do_trigger);
+  */
+ 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;
+@@ -1654,7 +1681,7 @@ static void __mcheck_cpu_clear_vendor(struct cpuinfo_x86 *c)
+ 	}
+ }
+ 
+-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 = check_interval * HZ;
+ 
+@@ -1663,16 +1690,17 @@ static void mce_start_timer(unsigned int cpu, struct timer_list *t)
+ 
+ 	per_cpu(mce_next_interval, cpu) = iv;
+ 
+-	t->expires = round_jiffies(jiffies + iv);
+-	add_timer_on(t, cpu);
++	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 = this_cpu_ptr(&mce_timer);
++	struct hrtimer *t = this_cpu_ptr(&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);
+ }
+ 
+@@ -2393,6 +2421,8 @@ static void mce_disable_cpu(void *h)
+ 	if (!mce_available(raw_cpu_ptr(&cpu_info)))
+ 		return;
+ 
++	hrtimer_cancel(this_cpu_ptr(&mce_timer));
++
+ 	if (!(action & CPU_TASKS_FROZEN))
+ 		cmci_clear();
+ 
+@@ -2415,6 +2445,7 @@ 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. */
+@@ -2422,7 +2453,6 @@ 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:
+@@ -2442,11 +2472,9 @@ mce_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu)
+ 		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;
+ 	}
+ 
+@@ -2485,6 +2513,10 @@ static __init int mcheck_init_device(void)
+ 		goto err_out;
+ 	}
+ 
++	err = mce_notify_work_init();
++	if (err)
++		goto err_out;
++
+ 	if (!zalloc_cpumask_var(&mce_device_initialized, GFP_KERNEL)) {
+ 		err = -ENOMEM;
+ 		goto err_out;
+diff --git a/arch/x86/kernel/dumpstack_32.c b/arch/x86/kernel/dumpstack_32.c
+index 464ffd69b92e..00db1aad1548 100644
+--- a/arch/x86/kernel/dumpstack_32.c
++++ b/arch/x86/kernel/dumpstack_32.c
+@@ -42,7 +42,7 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs,
+ 		unsigned long *stack, unsigned long bp,
+ 		const struct stacktrace_ops *ops, void *data)
+ {
+-	const unsigned cpu = get_cpu();
++	const unsigned cpu = get_cpu_light();
+ 	int graph = 0;
+ 	u32 *prev_esp;
+ 
+@@ -86,7 +86,7 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs,
+ 			break;
+ 		touch_nmi_watchdog();
+ 	}
+-	put_cpu();
++	put_cpu_light();
+ }
+ EXPORT_SYMBOL(dump_trace);
+ 
+diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c
+index 5f1c6266eb30..c331e3fef465 100644
+--- a/arch/x86/kernel/dumpstack_64.c
++++ b/arch/x86/kernel/dumpstack_64.c
+@@ -152,7 +152,7 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs,
+ 		unsigned long *stack, unsigned long bp,
+ 		const struct stacktrace_ops *ops, void *data)
+ {
+-	const unsigned cpu = get_cpu();
++	const unsigned cpu = get_cpu_light();
+ 	struct thread_info *tinfo;
+ 	unsigned long *irq_stack = (unsigned long *)per_cpu(irq_stack_ptr, cpu);
+ 	unsigned long dummy;
+@@ -241,7 +241,7 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs,
+ 	 * This handles the process stack:
+ 	 */
+ 	bp = ops->walk_stack(tinfo, stack, bp, ops, data, NULL, &graph);
+-	put_cpu();
++	put_cpu_light();
+ }
+ EXPORT_SYMBOL(dump_trace);
+ 
+@@ -255,7 +255,7 @@ show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs,
+ 	int cpu;
+ 	int i;
+ 
+-	preempt_disable();
++	migrate_disable();
+ 	cpu = smp_processor_id();
+ 
+ 	irq_stack_end	= (unsigned long *)(per_cpu(irq_stack_ptr, cpu));
+@@ -291,7 +291,7 @@ show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs,
+ 			pr_cont(" %016lx", *stack++);
+ 		touch_nmi_watchdog();
+ 	}
+-	preempt_enable();
++	migrate_enable();
+ 
+ 	pr_cont("\n");
+ 	show_trace_log_lvl(task, regs, sp, bp, log_lvl);
+diff --git a/arch/x86/kernel/irq_32.c b/arch/x86/kernel/irq_32.c
+index 38da8f29a9c8..ce71f7098f15 100644
+--- a/arch/x86/kernel/irq_32.c
++++ b/arch/x86/kernel/irq_32.c
+@@ -128,6 +128,7 @@ void irq_ctx_init(int cpu)
+ 	       cpu, per_cpu(hardirq_stack, cpu),  per_cpu(softirq_stack, cpu));
+ }
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
+ void do_softirq_own_stack(void)
+ {
+ 	struct thread_info *curstk;
+@@ -146,6 +147,7 @@ void do_softirq_own_stack(void)
+ 
+ 	call_on_stack(__do_softirq, isp);
+ }
++#endif
+ 
+ bool handle_irq(struct irq_desc *desc, struct pt_regs *regs)
+ {
+diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
+index 9f950917528b..4dd4beae917a 100644
+--- a/arch/x86/kernel/process_32.c
++++ b/arch/x86/kernel/process_32.c
+@@ -35,6 +35,7 @@
+ #include <linux/uaccess.h>
+ #include <linux/io.h>
+ #include <linux/kdebug.h>
++#include <linux/highmem.h>
+ 
+ #include <asm/pgtable.h>
+ #include <asm/ldt.h>
+@@ -210,6 +211,35 @@ start_thread(struct pt_regs *regs, unsigned long new_ip, unsigned long new_sp)
+ }
+ 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.
+@@ -286,6 +316,8 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_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
+diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
+index 1a2da0e5a373..a0c78a291f02 100644
+--- a/arch/x86/kvm/lapic.c
++++ b/arch/x86/kvm/lapic.c
+@@ -1870,6 +1870,7 @@ int kvm_create_lapic(struct kvm_vcpu *vcpu)
+ 	hrtimer_init(&apic->lapic_timer.timer, CLOCK_MONOTONIC,
+ 		     HRTIMER_MODE_ABS_PINNED);
+ 	apic->lapic_timer.timer.function = apic_timer_fn;
++	apic->lapic_timer.timer.irqsafe = 1;
+ 
+ 	/*
+ 	 * APIC is created enabled. This will prevent kvm_lapic_set_base from
+diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
+index 6b9701babaa1..9da12e3ebcc5 100644
+--- a/arch/x86/kvm/x86.c
++++ b/arch/x86/kvm/x86.c
+@@ -5855,6 +5855,13 @@ 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;
+diff --git a/arch/x86/mm/highmem_32.c b/arch/x86/mm/highmem_32.c
+index a6d739258137..bd24ba1c4a86 100644
+--- a/arch/x86/mm/highmem_32.c
++++ b/arch/x86/mm/highmem_32.c
+@@ -32,10 +32,11 @@ 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;
+ 
+-	preempt_disable();
++	preempt_disable_nort();
+ 	pagefault_disable();
+ 
+ 	if (!PageHighMem(page))
+@@ -45,7 +46,10 @@ void *kmap_atomic_prot(struct page *page, pgprot_t prot)
+ 	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();
+@@ -100,7 +107,7 @@ void __kunmap_atomic(void *kvaddr)
+ #endif
+ 
+ 	pagefault_enable();
+-	preempt_enable();
++	preempt_enable_nort();
+ }
+ EXPORT_SYMBOL(__kunmap_atomic);
+ 
+diff --git a/arch/x86/mm/iomap_32.c b/arch/x86/mm/iomap_32.c
+index 9c0ff045fdd4..dd25dd1671b6 100644
+--- a/arch/x86/mm/iomap_32.c
++++ b/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;
+ 
+@@ -65,7 +66,12 @@ void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot)
+ 	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;
+@@ -113,6 +119,9 @@ 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();
+ 	}
+diff --git a/arch/x86/platform/uv/tlb_uv.c b/arch/x86/platform/uv/tlb_uv.c
+index 3b6ec42718e4..7871083de089 100644
+--- a/arch/x86/platform/uv/tlb_uv.c
++++ b/arch/x86/platform/uv/tlb_uv.c
+@@ -714,9 +714,9 @@ static void destination_plugged(struct bau_desc *bau_desc,
+ 
+ 		quiesce_local_uvhub(hmaster);
+ 
+-		spin_lock(&hmaster->queue_lock);
++		raw_spin_lock(&hmaster->queue_lock);
+ 		reset_with_ipi(&bau_desc->distribution, bcp);
+-		spin_unlock(&hmaster->queue_lock);
++		raw_spin_unlock(&hmaster->queue_lock);
+ 
+ 		end_uvhub_quiesce(hmaster);
+ 
+@@ -736,9 +736,9 @@ static void destination_timeout(struct bau_desc *bau_desc,
+ 
+ 		quiesce_local_uvhub(hmaster);
+ 
+-		spin_lock(&hmaster->queue_lock);
++		raw_spin_lock(&hmaster->queue_lock);
+ 		reset_with_ipi(&bau_desc->distribution, bcp);
+-		spin_unlock(&hmaster->queue_lock);
++		raw_spin_unlock(&hmaster->queue_lock);
+ 
+ 		end_uvhub_quiesce(hmaster);
+ 
+@@ -759,7 +759,7 @@ static void disable_for_period(struct bau_control *bcp, struct ptc_stats *stat)
+ 	cycles_t tm1;
+ 
+ 	hmaster = bcp->uvhub_master;
+-	spin_lock(&hmaster->disable_lock);
++	raw_spin_lock(&hmaster->disable_lock);
+ 	if (!bcp->baudisabled) {
+ 		stat->s_bau_disabled++;
+ 		tm1 = get_cycles();
+@@ -772,7 +772,7 @@ static void disable_for_period(struct bau_control *bcp, struct ptc_stats *stat)
+ 			}
+ 		}
+ 	}
+-	spin_unlock(&hmaster->disable_lock);
++	raw_spin_unlock(&hmaster->disable_lock);
+ }
+ 
+ static void count_max_concurr(int stat, struct bau_control *bcp,
+@@ -835,7 +835,7 @@ static void record_send_stats(cycles_t time1, cycles_t time2,
+  */
+ static void uv1_throttle(struct bau_control *hmaster, struct ptc_stats *stat)
+ {
+-	spinlock_t *lock = &hmaster->uvhub_lock;
++	raw_spinlock_t *lock = &hmaster->uvhub_lock;
+ 	atomic_t *v;
+ 
+ 	v = &hmaster->active_descriptor_count;
+@@ -968,7 +968,7 @@ static int check_enable(struct bau_control *bcp, struct ptc_stats *stat)
+ 	struct bau_control *hmaster;
+ 
+ 	hmaster = bcp->uvhub_master;
+-	spin_lock(&hmaster->disable_lock);
++	raw_spin_lock(&hmaster->disable_lock);
+ 	if (bcp->baudisabled && (get_cycles() >= bcp->set_bau_on_time)) {
+ 		stat->s_bau_reenabled++;
+ 		for_each_present_cpu(tcpu) {
+@@ -980,10 +980,10 @@ static int check_enable(struct bau_control *bcp, struct ptc_stats *stat)
+ 				tbcp->period_giveups = 0;
+ 			}
+ 		}
+-		spin_unlock(&hmaster->disable_lock);
++		raw_spin_unlock(&hmaster->disable_lock);
+ 		return 0;
+ 	}
+-	spin_unlock(&hmaster->disable_lock);
++	raw_spin_unlock(&hmaster->disable_lock);
+ 	return -1;
+ }
+ 
+@@ -1901,9 +1901,9 @@ static void __init init_per_cpu_tunables(void)
+ 		bcp->cong_reps			= congested_reps;
+ 		bcp->disabled_period =		sec_2_cycles(disabled_period);
+ 		bcp->giveup_limit =		giveup_limit;
+-		spin_lock_init(&bcp->queue_lock);
+-		spin_lock_init(&bcp->uvhub_lock);
+-		spin_lock_init(&bcp->disable_lock);
++		raw_spin_lock_init(&bcp->queue_lock);
++		raw_spin_lock_init(&bcp->uvhub_lock);
++		raw_spin_lock_init(&bcp->disable_lock);
+ 	}
+ }
+ 
+diff --git a/arch/x86/platform/uv/uv_time.c b/arch/x86/platform/uv/uv_time.c
+index 2b158a9fa1d7..5e0b122620cb 100644
+--- a/arch/x86/platform/uv/uv_time.c
++++ b/arch/x86/platform/uv/uv_time.c
+@@ -57,7 +57,7 @@ static DEFINE_PER_CPU(struct clock_event_device, cpu_ced);
+ 
+ /* There is one of these allocated per node */
+ struct uv_rtc_timer_head {
+-	spinlock_t	lock;
++	raw_spinlock_t	lock;
+ 	/* next cpu waiting for timer, local node relative: */
+ 	int		next_cpu;
+ 	/* number of cpus on this node: */
+@@ -177,7 +177,7 @@ static __init int uv_rtc_allocate_timers(void)
+ 				uv_rtc_deallocate_timers();
+ 				return -ENOMEM;
+ 			}
+-			spin_lock_init(&head->lock);
++			raw_spin_lock_init(&head->lock);
+ 			head->ncpus = uv_blade_nr_possible_cpus(bid);
+ 			head->next_cpu = -1;
+ 			blade_info[bid] = head;
+@@ -231,7 +231,7 @@ static int uv_rtc_set_timer(int cpu, u64 expires)
+ 	unsigned long flags;
+ 	int next_cpu;
+ 
+-	spin_lock_irqsave(&head->lock, flags);
++	raw_spin_lock_irqsave(&head->lock, flags);
+ 
+ 	next_cpu = head->next_cpu;
+ 	*t = expires;
+@@ -243,12 +243,12 @@ static int uv_rtc_set_timer(int cpu, u64 expires)
+ 		if (uv_setup_intr(cpu, expires)) {
+ 			*t = ULLONG_MAX;
+ 			uv_rtc_find_next_timer(head, pnode);
+-			spin_unlock_irqrestore(&head->lock, flags);
++			raw_spin_unlock_irqrestore(&head->lock, flags);
+ 			return -ETIME;
+ 		}
+ 	}
+ 
+-	spin_unlock_irqrestore(&head->lock, flags);
++	raw_spin_unlock_irqrestore(&head->lock, flags);
+ 	return 0;
+ }
+ 
+@@ -267,7 +267,7 @@ static int uv_rtc_unset_timer(int cpu, int force)
+ 	unsigned long flags;
+ 	int rc = 0;
+ 
+-	spin_lock_irqsave(&head->lock, flags);
++	raw_spin_lock_irqsave(&head->lock, flags);
+ 
+ 	if ((head->next_cpu == bcpu && uv_read_rtc(NULL) >= *t) || force)
+ 		rc = 1;
+@@ -279,7 +279,7 @@ static int uv_rtc_unset_timer(int cpu, int force)
+ 			uv_rtc_find_next_timer(head, pnode);
+ 	}
+ 
+-	spin_unlock_irqrestore(&head->lock, flags);
++	raw_spin_unlock_irqrestore(&head->lock, flags);
+ 
+ 	return rc;
+ }
+@@ -299,13 +299,18 @@ static int uv_rtc_unset_timer(int cpu, int force)
+ static cycle_t uv_read_rtc(struct clocksource *cs)
+ {
+ 	unsigned long offset;
++	cycle_t cycles;
+ 
++	preempt_disable();
+ 	if (uv_get_min_hub_revision_id() == 1)
+ 		offset = 0;
+ 	else
+ 		offset = (uv_blade_processor_id() * L1_CACHE_BYTES) % PAGE_SIZE;
+ 
+-	return (cycle_t)uv_read_local_mmr(UVH_RTC | offset);
++	cycles = (cycle_t)uv_read_local_mmr(UVH_RTC | offset);
++	preempt_enable();
++
++	return cycles;
+ }
+ 
+ /*
+diff --git a/block/blk-core.c b/block/blk-core.c
+index b60537b2c35b..b9bdc9d0262d 100644
+--- a/block/blk-core.c
++++ b/block/blk-core.c
+@@ -125,6 +125,9 @@ void blk_rq_init(struct request_queue *q, struct request *rq)
+ 
+ 	INIT_LIST_HEAD(&rq->queuelist);
+ 	INIT_LIST_HEAD(&rq->timeout_list);
++#ifdef CONFIG_PREEMPT_RT_FULL
++	INIT_WORK(&rq->work, __blk_mq_complete_request_remote_work);
++#endif
+ 	rq->cpu = -1;
+ 	rq->q = q;
+ 	rq->__sector = (sector_t) -1;
+@@ -233,7 +236,7 @@ EXPORT_SYMBOL(blk_start_queue_async);
+  **/
+ 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);
+@@ -657,7 +660,7 @@ int blk_queue_enter(struct request_queue *q, bool nowait)
+ 		if (nowait)
+ 			return -EBUSY;
+ 
+-		ret = wait_event_interruptible(q->mq_freeze_wq,
++		ret = swait_event_interruptible(q->mq_freeze_wq,
+ 				!atomic_read(&q->mq_freeze_depth) ||
+ 				blk_queue_dying(q));
+ 		if (blk_queue_dying(q))
+@@ -677,7 +680,7 @@ static void blk_queue_usage_counter_release(struct percpu_ref *ref)
+ 	struct request_queue *q =
+ 		container_of(ref, struct request_queue, q_usage_counter);
+ 
+-	wake_up_all(&q->mq_freeze_wq);
++	swake_up_all(&q->mq_freeze_wq);
+ }
+ 
+ static void blk_rq_timed_out_timer(unsigned long data)
+@@ -746,7 +749,7 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id)
+ 	q->bypass_depth = 1;
+ 	__set_bit(QUEUE_FLAG_BYPASS, &q->queue_flags);
+ 
+-	init_waitqueue_head(&q->mq_freeze_wq);
++	init_swait_queue_head(&q->mq_freeze_wq);
+ 
+ 	/*
+ 	 * Init percpu_ref in atomic mode so that it's faster to shutdown.
+@@ -3209,7 +3212,7 @@ static void queue_unplugged(struct request_queue *q, unsigned int depth,
+ 		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)
+@@ -3257,7 +3260,6 @@ 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;
+@@ -3277,11 +3279,6 @@ void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule)
+ 	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);
+@@ -3294,7 +3291,7 @@ void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule)
+ 				queue_unplugged(q, depth, from_schedule);
+ 			q = rq->q;
+ 			depth = 0;
+-			spin_lock(q->queue_lock);
++			spin_lock_irq(q->queue_lock);
+ 		}
+ 
+ 		/*
+@@ -3321,8 +3318,6 @@ void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule)
+ 	 */
+ 	if (q)
+ 		queue_unplugged(q, depth, from_schedule);
+-
+-	local_irq_restore(flags);
+ }
+ 
+ void blk_finish_plug(struct blk_plug *plug)
+diff --git a/block/blk-ioc.c b/block/blk-ioc.c
+index 381cb50a673c..dc8785233d94 100644
+--- a/block/blk-ioc.c
++++ b/block/blk-ioc.c
+@@ -7,6 +7,7 @@
+ #include <linux/bio.h>
+ #include <linux/blkdev.h>
+ #include <linux/slab.h>
++#include <linux/delay.h>
+ 
+ #include "blk.h"
+ 
+@@ -109,7 +110,7 @@ static void ioc_release_fn(struct work_struct *work)
+ 			spin_unlock(q->queue_lock);
+ 		} else {
+ 			spin_unlock_irqrestore(&ioc->lock, flags);
+-			cpu_relax();
++			cpu_chill();
+ 			spin_lock_irqsave_nested(&ioc->lock, flags, 1);
+ 		}
+ 	}
+@@ -187,7 +188,7 @@ void put_io_context_active(struct io_context *ioc)
+ 			spin_unlock(icq->q->queue_lock);
+ 		} else {
+ 			spin_unlock_irqrestore(&ioc->lock, flags);
+-			cpu_relax();
++			cpu_chill();
+ 			goto retry;
+ 		}
+ 	}
+diff --git a/block/blk-mq-cpu.c b/block/blk-mq-cpu.c
+index bb3ed488f7b5..628c6c13c482 100644
+--- a/block/blk-mq-cpu.c
++++ b/block/blk-mq-cpu.c
+@@ -16,7 +16,7 @@
+ #include "blk-mq.h"
+ 
+ static LIST_HEAD(blk_mq_cpu_notify_list);
+-static DEFINE_RAW_SPINLOCK(blk_mq_cpu_notify_lock);
++static DEFINE_SPINLOCK(blk_mq_cpu_notify_lock);
+ 
+ static int blk_mq_main_cpu_notify(struct notifier_block *self,
+ 				  unsigned long action, void *hcpu)
+@@ -25,7 +25,10 @@ static int blk_mq_main_cpu_notify(struct notifier_block *self,
+ 	struct blk_mq_cpu_notifier *notify;
+ 	int ret = NOTIFY_OK;
+ 
+-	raw_spin_lock(&blk_mq_cpu_notify_lock);
++	if (action != CPU_POST_DEAD)
++		return NOTIFY_OK;
++
++	spin_lock(&blk_mq_cpu_notify_lock);
+ 
+ 	list_for_each_entry(notify, &blk_mq_cpu_notify_list, list) {
+ 		ret = notify->notify(notify->data, action, cpu);
+@@ -33,7 +36,7 @@ static int blk_mq_main_cpu_notify(struct notifier_block *self,
+ 			break;
+ 	}
+ 
+-	raw_spin_unlock(&blk_mq_cpu_notify_lock);
++	spin_unlock(&blk_mq_cpu_notify_lock);
+ 	return ret;
+ }
+ 
+@@ -41,16 +44,16 @@ void blk_mq_register_cpu_notifier(struct blk_mq_cpu_notifier *notifier)
+ {
+ 	BUG_ON(!notifier->notify);
+ 
+-	raw_spin_lock(&blk_mq_cpu_notify_lock);
++	spin_lock(&blk_mq_cpu_notify_lock);
+ 	list_add_tail(&notifier->list, &blk_mq_cpu_notify_list);
+-	raw_spin_unlock(&blk_mq_cpu_notify_lock);
++	spin_unlock(&blk_mq_cpu_notify_lock);
+ }
+ 
+ void blk_mq_unregister_cpu_notifier(struct blk_mq_cpu_notifier *notifier)
+ {
+-	raw_spin_lock(&blk_mq_cpu_notify_lock);
++	spin_lock(&blk_mq_cpu_notify_lock);
+ 	list_del(&notifier->list);
+-	raw_spin_unlock(&blk_mq_cpu_notify_lock);
++	spin_unlock(&blk_mq_cpu_notify_lock);
+ }
+ 
+ void blk_mq_init_cpu_notifier(struct blk_mq_cpu_notifier *notifier,
+diff --git a/block/blk-mq.c b/block/blk-mq.c
+index 1699baf39b78..2a2006009548 100644
+--- a/block/blk-mq.c
++++ b/block/blk-mq.c
+@@ -92,7 +92,7 @@ EXPORT_SYMBOL_GPL(blk_mq_freeze_queue_start);
+ 
+ static void blk_mq_freeze_queue_wait(struct request_queue *q)
+ {
+-	wait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->q_usage_counter));
++	swait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->q_usage_counter));
+ }
+ 
+ /*
+@@ -130,7 +130,7 @@ void blk_mq_unfreeze_queue(struct request_queue *q)
+ 	WARN_ON_ONCE(freeze_depth < 0);
+ 	if (!freeze_depth) {
+ 		percpu_ref_reinit(&q->q_usage_counter);
+-		wake_up_all(&q->mq_freeze_wq);
++		swake_up_all(&q->mq_freeze_wq);
+ 	}
+ }
+ EXPORT_SYMBOL_GPL(blk_mq_unfreeze_queue);
+@@ -149,7 +149,7 @@ void blk_mq_wake_waiters(struct request_queue *q)
+ 	 * dying, we need to ensure that processes currently waiting on
+ 	 * the queue are notified as well.
+ 	 */
+-	wake_up_all(&q->mq_freeze_wq);
++	swake_up_all(&q->mq_freeze_wq);
+ }
+ 
+ bool blk_mq_can_queue(struct blk_mq_hw_ctx *hctx)
+@@ -196,6 +196,9 @@ static void blk_mq_rq_ctx_init(struct request_queue *q, struct blk_mq_ctx *ctx,
+ 	rq->resid_len = 0;
+ 	rq->sense = NULL;
+ 
++#ifdef CONFIG_PREEMPT_RT_FULL
++	INIT_WORK(&rq->work, __blk_mq_complete_request_remote_work);
++#endif
+ 	INIT_LIST_HEAD(&rq->timeout_list);
+ 	rq->timeout = 0;
+ 
+@@ -323,6 +326,17 @@ void blk_mq_end_request(struct request *rq, int error)
+ }
+ EXPORT_SYMBOL(blk_mq_end_request);
+ 
++#ifdef CONFIG_PREEMPT_RT_FULL
++
++void __blk_mq_complete_request_remote_work(struct work_struct *work)
++{
++	struct request *rq = container_of(work, struct request, work);
++
++	rq->q->softirq_done_fn(rq);
++}
++
++#else
++
+ static void __blk_mq_complete_request_remote(void *data)
+ {
+ 	struct request *rq = data;
+@@ -330,6 +344,8 @@ static void __blk_mq_complete_request_remote(void *data)
+ 	rq->q->softirq_done_fn(rq);
+ }
+ 
++#endif
++
+ static void blk_mq_ipi_complete_request(struct request *rq)
+ {
+ 	struct blk_mq_ctx *ctx = rq->mq_ctx;
+@@ -341,19 +357,23 @@ static void blk_mq_ipi_complete_request(struct request *rq)
+ 		return;
+ 	}
+ 
+-	cpu = get_cpu();
++	cpu = get_cpu_light();
+ 	if (!test_bit(QUEUE_FLAG_SAME_FORCE, &rq->q->queue_flags))
+ 		shared = cpus_share_cache(cpu, ctx->cpu);
+ 
+ 	if (cpu != ctx->cpu && !shared && cpu_online(ctx->cpu)) {
++#ifdef CONFIG_PREEMPT_RT_FULL
++		schedule_work_on(ctx->cpu, &rq->work);
++#else
+ 		rq->csd.func = __blk_mq_complete_request_remote;
+ 		rq->csd.info = rq;
+ 		rq->csd.flags = 0;
+ 		smp_call_function_single_async(ctx->cpu, &rq->csd);
++#endif
+ 	} else {
+ 		rq->q->softirq_done_fn(rq);
+ 	}
+-	put_cpu();
++	put_cpu_light();
+ }
+ 
+ static void __blk_mq_complete_request(struct request *rq)
+@@ -868,14 +888,14 @@ void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async)
+ 		return;
+ 
+ 	if (!async) {
+-		int cpu = get_cpu();
++		int cpu = get_cpu_light();
+ 		if (cpumask_test_cpu(cpu, hctx->cpumask)) {
+ 			__blk_mq_run_hw_queue(hctx);
+-			put_cpu();
++			put_cpu_light();
+ 			return;
+ 		}
+ 
+-		put_cpu();
++		put_cpu_light();
+ 	}
+ 
+ 	kblockd_schedule_delayed_work_on(blk_mq_hctx_next_cpu(hctx),
+@@ -1621,7 +1641,7 @@ static int blk_mq_hctx_notify(void *data, unsigned long action,
+ {
+ 	struct blk_mq_hw_ctx *hctx = data;
+ 
+-	if (action == CPU_DEAD || action == CPU_DEAD_FROZEN)
++	if (action == CPU_POST_DEAD)
+ 		return blk_mq_hctx_cpu_offline(hctx, cpu);
+ 
+ 	/*
+diff --git a/block/blk-mq.h b/block/blk-mq.h
+index 9087b11037b7..0401d76e827c 100644
+--- a/block/blk-mq.h
++++ b/block/blk-mq.h
+@@ -86,12 +86,12 @@ static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q,
+  */
+ static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q)
+ {
+-	return __blk_mq_get_ctx(q, get_cpu());
++	return __blk_mq_get_ctx(q, get_cpu_light());
+ }
+ 
+ static inline void blk_mq_put_ctx(struct blk_mq_ctx *ctx)
+ {
+-	put_cpu();
++	put_cpu_light();
+ }
+ 
+ struct blk_mq_alloc_data {
+diff --git a/block/blk-softirq.c b/block/blk-softirq.c
+index 53b1737e978d..81c3c0a62edf 100644
+--- a/block/blk-softirq.c
++++ b/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 notifier_block *self, unsigned long action,
+ 				 this_cpu_ptr(&blk_cpu_done));
+ 		raise_softirq_irqoff(BLOCK_SOFTIRQ);
+ 		local_irq_enable();
++		preempt_check_resched_rt();
+ 	}
+ 
+ 	return NOTIFY_OK;
+@@ -150,6 +152,7 @@ void __blk_complete_request(struct request *req)
+ 		goto do_local;
+ 
+ 	local_irq_restore(flags);
++	preempt_check_resched_rt();
+ }
+ 
+ /**
+diff --git a/block/bounce.c b/block/bounce.c
+index 1cb5dd3a5da1..2f1ec8a67cbe 100644
+--- a/block/bounce.c
++++ b/block/bounce.c
+@@ -55,11 +55,11 @@ static void bounce_copy_vec(struct bio_vec *to, unsigned char *vfrom)
+ 	unsigned long flags;
+ 	unsigned char *vto;
+ 
+-	local_irq_save(flags);
++	local_irq_save_nort(flags);
+ 	vto = kmap_atomic(to->bv_page);
+ 	memcpy(vto + to->bv_offset, vfrom, to->bv_len);
+ 	kunmap_atomic(vto);
+-	local_irq_restore(flags);
++	local_irq_restore_nort(flags);
+ }
+ 
+ #else /* CONFIG_HIGHMEM */
+diff --git a/block/genhd.c b/block/genhd.c
+index 9f42526b4d62..f06d7f3b075b 100644
+--- a/block/genhd.c
++++ b/block/genhd.c
+@@ -1523,12 +1523,7 @@ static void __disk_unblock_events(struct gendisk *disk, bool check_now)
+ 	if (--ev->block)
+ 		goto out_unlock;
+ 
+-	/*
+-	 * Not exactly a latency critical operation, set poll timer
+-	 * slack to 25% and kick event check.
+-	 */
+ 	intv = disk_events_poll_jiffies(disk);
+-	set_timer_slack(&ev->dwork.timer, intv / 4);
+ 	if (check_now)
+ 		queue_delayed_work(system_freezable_power_efficient_wq,
+ 				&ev->dwork, 0);
+diff --git a/crypto/algapi.c b/crypto/algapi.c
+index 731255a6104f..d3380591dfdd 100644
+--- a/crypto/algapi.c
++++ b/crypto/algapi.c
+@@ -718,13 +718,13 @@ 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);
+ 
+diff --git a/crypto/api.c b/crypto/api.c
+index bbc147cb5dec..bc1a848f02ec 100644
+--- a/crypto/api.c
++++ b/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 val, void *v)
+ {
+ 	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;
+diff --git a/crypto/internal.h b/crypto/internal.h
+index 7eefcdb00227..0ecc7f5a2f40 100644
+--- a/crypto/internal.h
++++ b/crypto/internal.h
+@@ -47,7 +47,7 @@ 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);
+@@ -146,7 +146,7 @@ static inline int crypto_is_moribund(struct crypto_alg *alg)
+ 
+ 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 */
+diff --git a/drivers/acpi/acpica/acglobal.h b/drivers/acpi/acpica/acglobal.h
+index 51b073b68f16..2d38ca5c6635 100644
+--- a/drivers/acpi/acpica/acglobal.h
++++ b/drivers/acpi/acpica/acglobal.h
+@@ -116,7 +116,7 @@ ACPI_GLOBAL(u8, acpi_gbl_global_lock_pending);
+  * interrupt level
+  */
+ ACPI_GLOBAL(acpi_spinlock, acpi_gbl_gpe_lock);	/* For GPE data structs and registers */
+-ACPI_GLOBAL(acpi_spinlock, acpi_gbl_hardware_lock);	/* For ACPI H/W except GPE registers */
++ACPI_GLOBAL(acpi_raw_spinlock, acpi_gbl_hardware_lock);	/* For ACPI H/W except GPE registers */
+ ACPI_GLOBAL(acpi_spinlock, acpi_gbl_reference_count_lock);
+ 
+ /* Mutex for _OSI support */
+diff --git a/drivers/acpi/acpica/hwregs.c b/drivers/acpi/acpica/hwregs.c
+index 5ba0498412fd..ada43191fb31 100644
+--- a/drivers/acpi/acpica/hwregs.c
++++ b/drivers/acpi/acpica/hwregs.c
+@@ -269,14 +269,14 @@ acpi_status acpi_hw_clear_acpi_status(void)
+ 			  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;
+diff --git a/drivers/acpi/acpica/hwxface.c b/drivers/acpi/acpica/hwxface.c
+index a01ddb393a55..fb64afd9470b 100644
+--- a/drivers/acpi/acpica/hwxface.c
++++ b/drivers/acpi/acpica/hwxface.c
+@@ -374,7 +374,7 @@ acpi_status acpi_write_bit_register(u32 register_id, u32 value)
+ 		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
+@@ -435,7 +435,7 @@ acpi_status acpi_write_bit_register(u32 register_id, u32 value)
+ 
+ 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);
+ }
+ 
+diff --git a/drivers/acpi/acpica/utmutex.c b/drivers/acpi/acpica/utmutex.c
+index 15073375bd00..357e7ca5a587 100644
+--- a/drivers/acpi/acpica/utmutex.c
++++ b/drivers/acpi/acpica/utmutex.c
+@@ -88,7 +88,7 @@ acpi_status acpi_ut_mutex_initialize(void)
+ 		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);
+ 	}
+@@ -145,7 +145,7 @@ 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 */
+diff --git a/drivers/ata/libata-sff.c b/drivers/ata/libata-sff.c
+index 051b6158d1b7..7ad293bef6ed 100644
+--- a/drivers/ata/libata-sff.c
++++ b/drivers/ata/libata-sff.c
+@@ -678,9 +678,9 @@ unsigned int ata_sff_data_xfer_noirq(struct ata_device *dev, unsigned char *buf,
+ 	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_queued_cmd *qc)
+ 		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_queued_cmd *qc)
+ 				       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 @@ static int __atapi_pio_bytes(struct ata_queued_cmd *qc, unsigned int bytes)
+ 		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 @@ static int __atapi_pio_bytes(struct ata_queued_cmd *qc, unsigned int bytes)
+ 								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,
+diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
+index 370c2f76016d..65e0b375a291 100644
+--- a/drivers/block/zram/zram_drv.c
++++ b/drivers/block/zram/zram_drv.c
+@@ -520,6 +520,8 @@ static struct zram_meta *zram_meta_alloc(char *pool_name, u64 disksize)
+ 		goto out_error;
+ 	}
+ 
++	zram_meta_init_table_locks(meta, disksize);
++
+ 	return meta;
+ 
+ out_error:
+@@ -568,12 +570,12 @@ static int zram_decompress_page(struct zram *zram, char *mem, u32 index)
+ 	unsigned long handle;
+ 	size_t size;
+ 
+-	bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
++	zram_lock_table(&meta->table[index]);
+ 	handle = meta->table[index].handle;
+ 	size = zram_get_obj_size(meta, index);
+ 
+ 	if (!handle || zram_test_flag(meta, index, ZRAM_ZERO)) {
+-		bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
++		zram_unlock_table(&meta->table[index]);
+ 		clear_page(mem);
+ 		return 0;
+ 	}
+@@ -584,7 +586,7 @@ static int zram_decompress_page(struct zram *zram, char *mem, u32 index)
+ 	else
+ 		ret = zcomp_decompress(zram->comp, cmem, size, mem);
+ 	zs_unmap_object(meta->mem_pool, handle);
+-	bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
++	zram_unlock_table(&meta->table[index]);
+ 
+ 	/* Should NEVER happen. Return bio error if it does. */
+ 	if (unlikely(ret)) {
+@@ -604,14 +606,14 @@ static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec,
+ 	struct zram_meta *meta = zram->meta;
+ 	page = bvec->bv_page;
+ 
+-	bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
++	zram_lock_table(&meta->table[index]);
+ 	if (unlikely(!meta->table[index].handle) ||
+ 			zram_test_flag(meta, index, ZRAM_ZERO)) {
+-		bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
++		zram_unlock_table(&meta->table[index]);
+ 		handle_zero_page(bvec);
+ 		return 0;
+ 	}
+-	bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
++	zram_unlock_table(&meta->table[index]);
+ 
+ 	if (is_partial_io(bvec))
+ 		/* Use  a temporary buffer to decompress the page */
+@@ -689,10 +691,10 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
+ 		if (user_mem)
+ 			kunmap_atomic(user_mem);
+ 		/* Free memory associated with this sector now. */
+-		bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
++		zram_lock_table(&meta->table[index]);
+ 		zram_free_page(zram, index);
+ 		zram_set_flag(meta, index, ZRAM_ZERO);
+-		bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
++		zram_unlock_table(&meta->table[index]);
+ 
+ 		atomic64_inc(&zram->stats.zero_pages);
+ 		ret = 0;
+@@ -752,12 +754,12 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
+ 	 * Free memory associated with this sector
+ 	 * before overwriting unused sectors.
+ 	 */
+-	bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
++	zram_lock_table(&meta->table[index]);
+ 	zram_free_page(zram, index);
+ 
+ 	meta->table[index].handle = handle;
+ 	zram_set_obj_size(meta, index, clen);
+-	bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
++	zram_unlock_table(&meta->table[index]);
+ 
+ 	/* Update stats */
+ 	atomic64_add(clen, &zram->stats.compr_data_size);
+@@ -800,9 +802,9 @@ static void zram_bio_discard(struct zram *zram, u32 index,
+ 	}
+ 
+ 	while (n >= PAGE_SIZE) {
+-		bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
++		zram_lock_table(&meta->table[index]);
+ 		zram_free_page(zram, index);
+-		bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
++		zram_unlock_table(&meta->table[index]);
+ 		atomic64_inc(&zram->stats.notify_free);
+ 		index++;
+ 		n -= PAGE_SIZE;
+@@ -928,9 +930,9 @@ static void zram_slot_free_notify(struct block_device *bdev,
+ 	zram = bdev->bd_disk->private_data;
+ 	meta = zram->meta;
+ 
+-	bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
++	zram_lock_table(&meta->table[index]);
+ 	zram_free_page(zram, index);
+-	bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
++	zram_unlock_table(&meta->table[index]);
+ 	atomic64_inc(&zram->stats.notify_free);
+ }
+ 
+diff --git a/drivers/block/zram/zram_drv.h b/drivers/block/zram/zram_drv.h
+index 8e92339686d7..9e3e953d680e 100644
+--- a/drivers/block/zram/zram_drv.h
++++ b/drivers/block/zram/zram_drv.h
+@@ -72,6 +72,9 @@ enum zram_pageflags {
+ struct zram_table_entry {
+ 	unsigned long handle;
+ 	unsigned long value;
++#ifdef CONFIG_PREEMPT_RT_BASE
++	spinlock_t lock;
++#endif
+ };
+ 
+ struct zram_stats {
+@@ -119,4 +122,42 @@ struct zram {
+ 	 */
+ 	bool claim; /* Protected by bdev->bd_mutex */
+ };
++
++#ifndef CONFIG_PREEMPT_RT_BASE
++static inline void zram_lock_table(struct zram_table_entry *table)
++{
++	bit_spin_lock(ZRAM_ACCESS, &table->value);
++}
++
++static inline void zram_unlock_table(struct zram_table_entry *table)
++{
++	bit_spin_unlock(ZRAM_ACCESS, &table->value);
++}
++
++static inline void zram_meta_init_table_locks(struct zram_meta *meta, u64 disksize) { }
++#else /* CONFIG_PREEMPT_RT_BASE */
++static inline void zram_lock_table(struct zram_table_entry *table)
++{
++	spin_lock(&table->lock);
++	__set_bit(ZRAM_ACCESS, &table->value);
++}
++
++static inline void zram_unlock_table(struct zram_table_entry *table)
++{
++	__clear_bit(ZRAM_ACCESS, &table->value);
++	spin_unlock(&table->lock);
++}
++
++static inline void zram_meta_init_table_locks(struct zram_meta *meta, u64 disksize)
++{
++        size_t num_pages = disksize >> PAGE_SHIFT;
++        size_t index;
++
++        for (index = 0; index < num_pages; index++) {
++		spinlock_t *lock = &meta->table[index].lock;
++		spin_lock_init(lock);
++        }
++}
++#endif /* CONFIG_PREEMPT_RT_BASE */
++
+ #endif
+diff --git a/drivers/char/random.c b/drivers/char/random.c
+index b583e5336630..ac2bd8c62de9 100644
+--- a/drivers/char/random.c
++++ b/drivers/char/random.c
+@@ -796,8 +796,6 @@ static void add_timer_randomness(struct timer_rand_state *state, unsigned num)
+ 	} sample;
+ 	long delta, delta2, delta3;
+ 
+-	preempt_disable();
+-
+ 	sample.jiffies = jiffies;
+ 	sample.cycles = random_get_entropy();
+ 	sample.num = num;
+@@ -838,7 +836,6 @@ static void add_timer_randomness(struct timer_rand_state *state, unsigned num)
+ 		 */
+ 		credit_entropy_bits(r, min_t(int, fls(delta>>1), 11));
+ 	}
+-	preempt_enable();
+ }
+ 
+ void add_input_randomness(unsigned int type, unsigned int code,
+@@ -891,28 +888,27 @@ static __u32 get_reg(struct fast_pool *f, struct pt_regs *regs)
+ 	return *(ptr + f->reg_idx++);
+ }
+ 
+-void add_interrupt_randomness(int irq, int irq_flags)
++void add_interrupt_randomness(int irq, int irq_flags, __u64 ip)
+ {
+ 	struct entropy_store	*r;
+ 	struct fast_pool	*fast_pool = this_cpu_ptr(&irq_randomness);
+-	struct pt_regs		*regs = get_irq_regs();
+ 	unsigned long		now = jiffies;
+ 	cycles_t		cycles = random_get_entropy();
+ 	__u32			c_high, j_high;
+-	__u64			ip;
+ 	unsigned long		seed;
+ 	int			credit = 0;
+ 
+ 	if (cycles == 0)
+-		cycles = get_reg(fast_pool, regs);
++		cycles = get_reg(fast_pool, NULL);
+ 	c_high = (sizeof(cycles) > 4) ? cycles >> 32 : 0;
+ 	j_high = (sizeof(now) > 4) ? now >> 32 : 0;
+ 	fast_pool->pool[0] ^= cycles ^ j_high ^ irq;
+ 	fast_pool->pool[1] ^= now ^ c_high;
+-	ip = regs ? instruction_pointer(regs) : _RET_IP_;
++	if (!ip)
++		ip = _RET_IP_;
+ 	fast_pool->pool[2] ^= ip;
+ 	fast_pool->pool[3] ^= (sizeof(ip) > 4) ? ip >> 32 :
+-		get_reg(fast_pool, regs);
++		get_reg(fast_pool, NULL);
+ 
+ 	fast_mix(fast_pool);
+ 	add_interrupt_bench(cycles);
+diff --git a/drivers/clocksource/tcb_clksrc.c b/drivers/clocksource/tcb_clksrc.c
+index 4da2af9694a2..5b6f57f500b8 100644
+--- a/drivers/clocksource/tcb_clksrc.c
++++ b/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 +73,8 @@ static struct clocksource clksrc = {
+ struct tc_clkevt_device {
+ 	struct clock_event_device	clkevt;
+ 	struct clk			*clk;
++	bool				clk_enabled;
++	u32				freq;
+ 	void __iomem			*regs;
+ };
+ 
+@@ -82,15 +83,26 @@ static struct tc_clkevt_device *to_tc_clkevt(struct clock_event_device *clkevt)
+ 	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_clk_disable(struct clock_event_device *d)
++{
++	struct tc_clkevt_device *tcd = to_tc_clkevt(d);
++
++	clk_disable(tcd->clk);
++	tcd->clk_enabled = false;
++}
++
++static void tc_clk_enable(struct clock_event_device *d)
++{
++	struct tc_clkevt_device *tcd = to_tc_clkevt(d);
++
++	if (tcd->clk_enabled)
++		return;
++	clk_enable(tcd->clk);
++	tcd->clk_enabled = true;
++}
++
+ static int tc_shutdown(struct clock_event_device *d)
+ {
+ 	struct tc_clkevt_device *tcd = to_tc_clkevt(d);
+@@ -98,8 +110,14 @@ static int tc_shutdown(struct clock_event_device *d)
+ 
+ 	__raw_writel(0xff, regs + ATMEL_TC_REG(2, IDR));
+ 	__raw_writel(ATMEL_TC_CLKDIS, regs + ATMEL_TC_REG(2, CCR));
++	return 0;
++}
++
++static int tc_shutdown_clk_off(struct clock_event_device *d)
++{
++	tc_shutdown(d);
+ 	if (!clockevent_state_detached(d))
+-		clk_disable(tcd->clk);
++		tc_clk_disable(d);
+ 
+ 	return 0;
+ }
+@@ -112,9 +130,9 @@ static int tc_set_oneshot(struct clock_event_device *d)
+ 	if (clockevent_state_oneshot(d) || clockevent_state_periodic(d))
+ 		tc_shutdown(d);
+ 
+-	clk_enable(tcd->clk);
++	tc_clk_enable(d);
+ 
+-	/* 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));
+ 	__raw_writel(ATMEL_TC_CPCS, regs + ATMEL_TC_REG(2, IER));
+@@ -134,12 +152,12 @@ static int tc_set_periodic(struct clock_event_device *d)
+ 	/* By not making the gentime core emulate periodic mode on top
+ 	 * of oneshot, we get lower overhead and improved accuracy.
+ 	 */
+-	clk_enable(tcd->clk);
++	tc_clk_enable(d);
+ 
+-	/* 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));
+@@ -166,9 +184,13 @@ static struct tc_clkevt_device clkevt = {
+ 		.features		= CLOCK_EVT_FEAT_PERIODIC |
+ 					  CLOCK_EVT_FEAT_ONESHOT,
+ 		/* Should be lower than at91rm9200's system timer */
++#ifdef CONFIG_ATMEL_TCB_CLKSRC_USE_SLOW_CLOCK
+ 		.rating			= 125,
++#else
++		.rating			= 200,
++#endif
+ 		.set_next_event		= tc_next_event,
+-		.set_state_shutdown	= tc_shutdown,
++		.set_state_shutdown	= tc_shutdown_clk_off,
+ 		.set_state_periodic	= tc_set_periodic,
+ 		.set_state_oneshot	= tc_set_oneshot,
+ 	},
+@@ -188,8 +210,9 @@ static irqreturn_t ch2_irq(int irq, void *handle)
+ 	return IRQ_NONE;
+ }
+ 
+-static int __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx)
++static int __init setup_clkevents(struct atmel_tc *tc, int divisor_idx)
+ {
++	unsigned divisor = atmel_tc_divisors[divisor_idx];
+ 	int ret;
+ 	struct clk *t2_clk = tc->clk[2];
+ 	int irq = tc->irq[2];
+@@ -210,7 +233,11 @@ static int __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx)
+ 	clkevt.regs = tc->regs;
+ 	clkevt.clk = t2_clk;
+ 
+-	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);
+ 
+@@ -221,7 +248,7 @@ static int __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx)
+ 		return ret;
+ 	}
+ 
+-	clockevents_config_and_register(&clkevt.clkevt, 32768, 1, 0xffff);
++	clockevents_config_and_register(&clkevt.clkevt, clkevt.freq, 1, 0xffff);
+ 
+ 	return ret;
+ }
+@@ -358,7 +385,11 @@ static int __init tcb_clksrc_init(void)
+ 		goto err_disable_t1;
+ 
+ 	/* channel 2:  periodic and oneshot timer support */
++#ifdef CONFIG_ATMEL_TCB_CLKSRC_USE_SLOW_CLOCK
+ 	ret = setup_clkevents(tc, clk32k_divisor_idx);
++#else
++	ret = setup_clkevents(tc, best_divisor_idx);
++#endif
+ 	if (ret)
+ 		goto err_unregister_clksrc;
+ 
+diff --git a/drivers/clocksource/timer-atmel-pit.c b/drivers/clocksource/timer-atmel-pit.c
+index d911c5dca8f1..7a40f7e88468 100644
+--- a/drivers/clocksource/timer-atmel-pit.c
++++ b/drivers/clocksource/timer-atmel-pit.c
+@@ -46,6 +46,7 @@ struct pit_data {
+ 	u32		cycle;
+ 	u32		cnt;
+ 	unsigned int	irq;
++	bool		irq_requested;
+ 	struct clk	*mck;
+ };
+ 
+@@ -96,15 +97,29 @@ static int pit_clkevt_shutdown(struct clock_event_device *dev)
+ 
+ 	/* disable irq, leaving the clocksource active */
+ 	pit_write(data->base, AT91_PIT_MR, (data->cycle - 1) | AT91_PIT_PITEN);
++	if (data->irq_requested) {
++		free_irq(data->irq, data);
++		data->irq_requested = false;
++	}
+ 	return 0;
+ }
+ 
++static irqreturn_t at91sam926x_pit_interrupt(int irq, void *dev_id);
+ /*
+  * Clockevent device:  interrupts every 1/HZ (== pit_cycles * MCK/16)
+  */
+ static int pit_clkevt_set_periodic(struct clock_event_device *dev)
+ {
+ 	struct pit_data *data = clkevt_to_pit_data(dev);
++	int ret;
++
++	ret = request_irq(data->irq, at91sam926x_pit_interrupt,
++			  IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
++			  "at91_tick", data);
++	if (ret)
++		panic(pr_fmt("Unable to setup IRQ\n"));
++
++	data->irq_requested = true;
+ 
+ 	/* update clocksource counter */
+ 	data->cnt += data->cycle * PIT_PICNT(pit_read(data->base, AT91_PIT_PIVR));
+@@ -181,7 +196,6 @@ static void __init at91sam926x_pit_common_init(struct pit_data *data)
+ {
+ 	unsigned long	pit_rate;
+ 	unsigned	bits;
+-	int		ret;
+ 
+ 	/*
+ 	 * Use our actual MCK to figure out how many MCK/16 ticks per
+@@ -206,13 +220,6 @@ static void __init at91sam926x_pit_common_init(struct pit_data *data)
+ 	data->clksrc.flags = CLOCK_SOURCE_IS_CONTINUOUS;
+ 	clocksource_register_hz(&data->clksrc, pit_rate);
+ 
+-	/* Set up irq handler */
+-	ret = request_irq(data->irq, at91sam926x_pit_interrupt,
+-			  IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
+-			  "at91_tick", data);
+-	if (ret)
+-		panic(pr_fmt("Unable to setup IRQ\n"));
+-
+ 	/* Set up and register clockevents */
+ 	data->clkevt.name = "pit";
+ 	data->clkevt.features = CLOCK_EVT_FEAT_PERIODIC;
+diff --git a/drivers/clocksource/timer-atmel-st.c b/drivers/clocksource/timer-atmel-st.c
+index 29d21d68df5a..103d0fd70cc4 100644
+--- a/drivers/clocksource/timer-atmel-st.c
++++ b/drivers/clocksource/timer-atmel-st.c
+@@ -115,18 +115,29 @@ static void clkdev32k_disable_and_flush_irq(void)
+ 	last_crtr = read_CRTR();
+ }
+ 
++static int atmel_st_irq;
++
+ static int clkevt32k_shutdown(struct clock_event_device *evt)
+ {
+ 	clkdev32k_disable_and_flush_irq();
+ 	irqmask = 0;
+ 	regmap_write(regmap_st, AT91_ST_IER, irqmask);
++	free_irq(atmel_st_irq, regmap_st);
+ 	return 0;
+ }
+ 
+ static int clkevt32k_set_oneshot(struct clock_event_device *dev)
+ {
++	int ret;
++
+ 	clkdev32k_disable_and_flush_irq();
+ 
++	ret = request_irq(atmel_st_irq, at91rm9200_timer_interrupt,
++			  IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
++			  "at91_tick", regmap_st);
++	if (ret)
++		panic(pr_fmt("Unable to setup IRQ\n"));
++
+ 	/*
+ 	 * ALM for oneshot irqs, set by next_event()
+ 	 * before 32 seconds have passed.
+@@ -139,8 +150,16 @@ static int clkevt32k_set_oneshot(struct clock_event_device *dev)
+ 
+ static int clkevt32k_set_periodic(struct clock_event_device *dev)
+ {
++	int ret;
++
+ 	clkdev32k_disable_and_flush_irq();
+ 
++	ret = request_irq(atmel_st_irq, at91rm9200_timer_interrupt,
++			  IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
++			  "at91_tick", regmap_st);
++	if (ret)
++		panic(pr_fmt("Unable to setup IRQ\n"));
++
+ 	/* PIT for periodic irqs; fixed rate of 1/HZ */
+ 	irqmask = AT91_ST_PITS;
+ 	regmap_write(regmap_st, AT91_ST_PIMR, timer_latch);
+@@ -198,7 +217,7 @@ static void __init atmel_st_timer_init(struct device_node *node)
+ {
+ 	struct clk *sclk;
+ 	unsigned int sclk_rate, val;
+-	int irq, ret;
++	int ret;
+ 
+ 	regmap_st = syscon_node_to_regmap(node);
+ 	if (IS_ERR(regmap_st))
+@@ -210,17 +229,10 @@ static void __init atmel_st_timer_init(struct device_node *node)
+ 	regmap_read(regmap_st, AT91_ST_SR, &val);
+ 
+ 	/* Get the interrupts property */
+-	irq  = irq_of_parse_and_map(node, 0);
+-	if (!irq)
++	atmel_st_irq  = irq_of_parse_and_map(node, 0);
++	if (!atmel_st_irq)
+ 		panic(pr_fmt("Unable to get IRQ from DT\n"));
+ 
+-	/* Make IRQs happen for the system timer */
+-	ret = request_irq(irq, at91rm9200_timer_interrupt,
+-			  IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
+-			  "at91_tick", regmap_st);
+-	if (ret)
+-		panic(pr_fmt("Unable to setup IRQ\n"));
+-
+ 	sclk = of_clk_get(node, 0);
+ 	if (IS_ERR(sclk))
+ 		panic(pr_fmt("Unable to get slow clock\n"));
+diff --git a/drivers/cpufreq/Kconfig.x86 b/drivers/cpufreq/Kconfig.x86
+index c59bdcb83217..8f23161d80be 100644
+--- a/drivers/cpufreq/Kconfig.x86
++++ b/drivers/cpufreq/Kconfig.x86
+@@ -123,7 +123,7 @@ config X86_POWERNOW_K7_ACPI
+ 
+ config X86_POWERNOW_K8
+ 	tristate "AMD Opteron/Athlon64 PowerNow!"
+-	depends on ACPI && ACPI_PROCESSOR && X86_ACPI_CPUFREQ
++	depends on ACPI && ACPI_PROCESSOR && X86_ACPI_CPUFREQ && !PREEMPT_RT_BASE
+ 	help
+ 	  This adds the CPUFreq driver for K8/early Opteron/Athlon64 processors.
+ 	  Support for K10 and newer processors is now in acpi-cpufreq.
+diff --git a/drivers/crypto/ccp/ccp-dev.c b/drivers/crypto/ccp/ccp-dev.c
+index 4dbc18727235..2a8ad712a5f2 100644
+--- a/drivers/crypto/ccp/ccp-dev.c
++++ b/drivers/crypto/ccp/ccp-dev.c
+@@ -16,7 +16,6 @@
+ #include <linux/sched.h>
+ #include <linux/interrupt.h>
+ #include <linux/spinlock.h>
+-#include <linux/rwlock_types.h>
+ #include <linux/types.h>
+ #include <linux/mutex.h>
+ #include <linux/delay.h>
+diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
+index daba7ebb9699..18d58f136628 100644
+--- a/drivers/gpu/drm/i915/i915_drv.h
++++ b/drivers/gpu/drm/i915/i915_drv.h
+@@ -714,7 +714,7 @@ struct intel_uncore {
+ 		struct drm_i915_private *i915;
+ 		enum forcewake_domain_id id;
+ 		unsigned wake_count;
+-		struct timer_list timer;
++		struct hrtimer timer;
+ 		i915_reg_t reg_set;
+ 		u32 val_set;
+ 		u32 val_clear;
+diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+index 1328bc5021b4..62103660b4c7 100644
+--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
++++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+@@ -1314,7 +1314,9 @@ i915_gem_ringbuffer_submission(struct i915_execbuffer_params *params,
+ 	if (ret)
+ 		return ret;
+ 
++#ifndef CONFIG_PREEMPT_RT_BASE
+ 	trace_i915_gem_ring_dispatch(params->request, params->dispatch_flags);
++#endif
+ 
+ 	i915_gem_execbuffer_move_to_active(vmas, params->request);
+ 	i915_gem_execbuffer_retire_commands(params);
+diff --git a/drivers/gpu/drm/i915/i915_gem_shrinker.c b/drivers/gpu/drm/i915/i915_gem_shrinker.c
+index 3af40616bf8b..46882680468e 100644
+--- a/drivers/gpu/drm/i915/i915_gem_shrinker.c
++++ b/drivers/gpu/drm/i915/i915_gem_shrinker.c
+@@ -39,7 +39,7 @@ static bool mutex_is_locked_by(struct mutex *mutex, struct task_struct *task)
+ 	if (!mutex_is_locked(mutex))
+ 		return false;
+ 
+-#if defined(CONFIG_DEBUG_MUTEXES) || defined(CONFIG_MUTEX_SPIN_ON_OWNER)
++#if (defined(CONFIG_DEBUG_MUTEXES) || defined(CONFIG_MUTEX_SPIN_ON_OWNER)) && !defined(CONFIG_PREEMPT_RT_BASE)
+ 	return mutex->owner == task;
+ #else
+ 	/* Since UP may be pre-empted, we cannot assume that we own the lock */
+diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
+index d1a46ef5ab3f..7d43f913de24 100644
+--- a/drivers/gpu/drm/i915/i915_irq.c
++++ b/drivers/gpu/drm/i915/i915_irq.c
+@@ -830,6 +830,7 @@ static int i915_get_crtc_scanoutpos(struct drm_device *dev, unsigned int pipe,
+ 	spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
+ 
+ 	/* preempt_disable_rt() should go right here in PREEMPT_RT patchset. */
++	preempt_disable_rt();
+ 
+ 	/* Get optional system timestamp before query. */
+ 	if (stime)
+@@ -881,6 +882,7 @@ static int i915_get_crtc_scanoutpos(struct drm_device *dev, unsigned int pipe,
+ 		*etime = ktime_get();
+ 
+ 	/* preempt_enable_rt() should go right here in PREEMPT_RT patchset. */
++	preempt_enable_rt();
+ 
+ 	spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
+ 
+diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
+index e5db9e1f623f..5ca085d99181 100644
+--- a/drivers/gpu/drm/i915/intel_display.c
++++ b/drivers/gpu/drm/i915/intel_display.c
+@@ -11496,7 +11496,7 @@ void intel_check_page_flip(struct drm_device *dev, int pipe)
+ 	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
+ 	struct intel_unpin_work *work;
+ 
+-	WARN_ON(!in_interrupt());
++	WARN_ON_NONRT(!in_interrupt());
+ 
+ 	if (crtc == NULL)
+ 		return;
+diff --git a/drivers/gpu/drm/i915/intel_sprite.c b/drivers/gpu/drm/i915/intel_sprite.c
+index a2582c455b36..c459b91586b0 100644
+--- a/drivers/gpu/drm/i915/intel_sprite.c
++++ b/drivers/gpu/drm/i915/intel_sprite.c
+@@ -38,6 +38,7 @@
+ #include "intel_drv.h"
+ #include <drm/i915_drm.h>
+ #include "i915_drv.h"
++#include <linux/locallock.h>
+ 
+ static bool
+ format_is_yuv(uint32_t format)
+@@ -64,6 +65,8 @@ static int usecs_to_scanlines(const struct drm_display_mode *adjusted_mode,
+ 			    1000 * adjusted_mode->crtc_htotal);
+ }
+ 
++static DEFINE_LOCAL_IRQ_LOCK(pipe_update_lock);
++
+ /**
+  * intel_pipe_update_start() - start update of a set of display registers
+  * @crtc: the crtc of which the registers are going to be updated
+@@ -96,7 +99,7 @@ void intel_pipe_update_start(struct intel_crtc *crtc)
+ 	min = vblank_start - usecs_to_scanlines(adjusted_mode, 100);
+ 	max = vblank_start - 1;
+ 
+-	local_irq_disable();
++	local_lock_irq(pipe_update_lock);
+ 
+ 	if (min <= 0 || max <= 0)
+ 		return;
+@@ -126,11 +129,11 @@ void intel_pipe_update_start(struct intel_crtc *crtc)
+ 			break;
+ 		}
+ 
+-		local_irq_enable();
++		local_unlock_irq(pipe_update_lock);
+ 
+ 		timeout = schedule_timeout(timeout);
+ 
+-		local_irq_disable();
++		local_lock_irq(pipe_update_lock);
+ 	}
+ 
+ 	finish_wait(wq, &wait);
+@@ -164,7 +167,7 @@ void intel_pipe_update_end(struct intel_crtc *crtc)
+ 
+ 	trace_i915_pipe_update_end(crtc, end_vbl_count, scanline_end);
+ 
+-	local_irq_enable();
++	local_unlock_irq(pipe_update_lock);
+ 
+ 	if (crtc->debug.start_vbl_count &&
+ 	    crtc->debug.start_vbl_count != end_vbl_count) {
+diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c
+index 68b6f69aa682..49aefb097c15 100644
+--- a/drivers/gpu/drm/i915/intel_uncore.c
++++ b/drivers/gpu/drm/i915/intel_uncore.c
+@@ -60,7 +60,11 @@ fw_domain_reset(const struct intel_uncore_forcewake_domain *d)
+ static inline void
+ fw_domain_arm_timer(struct intel_uncore_forcewake_domain *d)
+ {
+-	mod_timer_pinned(&d->timer, jiffies + 1);
++	d->wake_count++;
++	hrtimer_start_range_ns(&d->timer,
++			       ktime_set(0, NSEC_PER_MSEC),
++			       NSEC_PER_MSEC,
++			       HRTIMER_MODE_REL);
+ }
+ 
+ static inline void
+@@ -224,9 +228,11 @@ static int __gen6_gt_wait_for_fifo(struct drm_i915_private *dev_priv)
+ 	return ret;
+ }
+ 
+-static void intel_uncore_fw_release_timer(unsigned long arg)
++static enum hrtimer_restart
++intel_uncore_fw_release_timer(struct hrtimer *timer)
+ {
+-	struct intel_uncore_forcewake_domain *domain = (void *)arg;
++	struct intel_uncore_forcewake_domain *domain =
++	       container_of(timer, struct intel_uncore_forcewake_domain, timer);
+ 	unsigned long irqflags;
+ 
+ 	assert_rpm_device_not_suspended(domain->i915);
+@@ -240,6 +246,8 @@ static void intel_uncore_fw_release_timer(unsigned long arg)
+ 							  1 << domain->id);
+ 
+ 	spin_unlock_irqrestore(&domain->i915->uncore.lock, irqflags);
++
++	return HRTIMER_NORESTART;
+ }
+ 
+ void intel_uncore_forcewake_reset(struct drm_device *dev, bool restore)
+@@ -259,16 +267,16 @@ void intel_uncore_forcewake_reset(struct drm_device *dev, bool restore)
+ 		active_domains = 0;
+ 
+ 		for_each_fw_domain(domain, dev_priv, id) {
+-			if (del_timer_sync(&domain->timer) == 0)
++			if (hrtimer_cancel(&domain->timer) == 0)
+ 				continue;
+ 
+-			intel_uncore_fw_release_timer((unsigned long)domain);
++			intel_uncore_fw_release_timer(&domain->timer);
+ 		}
+ 
+ 		spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
+ 
+ 		for_each_fw_domain(domain, dev_priv, id) {
+-			if (timer_pending(&domain->timer))
++			if (hrtimer_active(&domain->timer))
+ 				active_domains |= (1 << id);
+ 		}
+ 
+@@ -491,7 +499,6 @@ static void __intel_uncore_forcewake_put(struct drm_i915_private *dev_priv,
+ 		if (--domain->wake_count)
+ 			continue;
+ 
+-		domain->wake_count++;
+ 		fw_domain_arm_timer(domain);
+ 	}
+ }
+@@ -732,7 +739,6 @@ static inline void __force_wake_get(struct drm_i915_private *dev_priv,
+ 			continue;
+ 		}
+ 
+-		domain->wake_count++;
+ 		fw_domain_arm_timer(domain);
+ 	}
+ 
+@@ -1150,7 +1156,8 @@ static void fw_domain_init(struct drm_i915_private *dev_priv,
+ 	d->i915 = dev_priv;
+ 	d->id = domain_id;
+ 
+-	setup_timer(&d->timer, intel_uncore_fw_release_timer, (unsigned long)d);
++	hrtimer_init(&d->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
++	d->timer.function = intel_uncore_fw_release_timer;
+ 
+ 	dev_priv->uncore.fw_domains |= (1 << domain_id);
+ 
+diff --git a/drivers/gpu/drm/radeon/radeon_display.c b/drivers/gpu/drm/radeon/radeon_display.c
+index fcc7483d3f7b..dc44af5675d9 100644
+--- a/drivers/gpu/drm/radeon/radeon_display.c
++++ b/drivers/gpu/drm/radeon/radeon_display.c
+@@ -1863,6 +1863,7 @@ int radeon_get_crtc_scanoutpos(struct drm_device *dev, unsigned int pipe,
+ 	struct radeon_device *rdev = dev->dev_private;
+ 
+ 	/* preempt_disable_rt() should go right here in PREEMPT_RT patchset. */
++	preempt_disable_rt();
+ 
+ 	/* Get optional system timestamp before query. */
+ 	if (stime)
+@@ -1955,6 +1956,7 @@ int radeon_get_crtc_scanoutpos(struct drm_device *dev, unsigned int pipe,
+ 		*etime = ktime_get();
+ 
+ 	/* preempt_enable_rt() should go right here in PREEMPT_RT patchset. */
++	preempt_enable_rt();
+ 
+ 	/* Decode into vertical and horizontal scanout position. */
+ 	*vpos = position & 0x1fff;
+diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
+index 13c45296ce5b..50c035c73357 100644
+--- a/drivers/i2c/busses/i2c-omap.c
++++ b/drivers/i2c/busses/i2c-omap.c
+@@ -995,15 +995,12 @@ omap_i2c_isr(int irq, void *dev_id)
+ 	u16 mask;
+ 	u16 stat;
+ 
+-	spin_lock(&omap->lock);
+-	mask = omap_i2c_read_reg(omap, OMAP_I2C_IE_REG);
+ 	stat = omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG);
++	mask = omap_i2c_read_reg(omap, OMAP_I2C_IE_REG);
+ 
+ 	if (stat & mask)
+ 		ret = IRQ_WAKE_THREAD;
+ 
+-	spin_unlock(&omap->lock);
+-
+ 	return ret;
+ }
+ 
+diff --git a/drivers/ide/alim15x3.c b/drivers/ide/alim15x3.c
+index 36f76e28a0bf..394f142f90c7 100644
+--- a/drivers/ide/alim15x3.c
++++ b/drivers/ide/alim15x3.c
+@@ -234,7 +234,7 @@ static int init_chipset_ali15x3(struct pci_dev *dev)
+ 
+ 	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 @@ static int init_chipset_ali15x3(struct pci_dev *dev)
+ 	}
+ 	pci_dev_put(north);
+ 	pci_dev_put(isa_dev);
+-	local_irq_restore(flags);
++	local_irq_restore_nort(flags);
+ 	return 0;
+ }
+ 
+diff --git a/drivers/ide/hpt366.c b/drivers/ide/hpt366.c
+index f94baadbf424..71c41cfe85e9 100644
+--- a/drivers/ide/hpt366.c
++++ b/drivers/ide/hpt366.c
+@@ -1236,7 +1236,7 @@ static int init_dma_hpt366(ide_hwif_t *hwif,
+ 
+ 	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);
+@@ -1247,7 +1247,7 @@ static int init_dma_hpt366(ide_hwif_t *hwif,
+ 	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);
+diff --git a/drivers/ide/ide-io-std.c b/drivers/ide/ide-io-std.c
+index 19763977568c..4169433faab5 100644
+--- a/drivers/ide/ide-io-std.c
++++ b/drivers/ide/ide-io-std.c
+@@ -175,7 +175,7 @@ void ide_input_data(ide_drive_t *drive, struct ide_cmd *cmd, void *buf,
+ 		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, struct ide_cmd *cmd, void *buf,
+ 			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, struct ide_cmd *cmd, void *buf,
+ 		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, struct ide_cmd *cmd, void *buf,
+ 			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;
+diff --git a/drivers/ide/ide-io.c b/drivers/ide/ide-io.c
+index 669ea1e45795..e12e43e62245 100644
+--- a/drivers/ide/ide-io.c
++++ b/drivers/ide/ide-io.c
+@@ -659,7 +659,7 @@ void ide_timer_expiry (unsigned long data)
+ 		/* 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)) {
+diff --git a/drivers/ide/ide-iops.c b/drivers/ide/ide-iops.c
+index 376f2dc410c5..f014dd1b73dc 100644
+--- a/drivers/ide/ide-iops.c
++++ b/drivers/ide/ide-iops.c
+@@ -129,12 +129,12 @@ int __ide_wait_stat(ide_drive_t *drive, u8 good, u8 bad,
+ 				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.
+diff --git a/drivers/ide/ide-probe.c b/drivers/ide/ide-probe.c
+index 0b63facd1d87..4ceba37afc0c 100644
+--- a/drivers/ide/ide-probe.c
++++ b/drivers/ide/ide-probe.c
+@@ -196,10 +196,10 @@ static void do_identify(ide_drive_t *drive, u8 cmd, u16 *id)
+ 	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
+diff --git a/drivers/ide/ide-taskfile.c b/drivers/ide/ide-taskfile.c
+index a716693417a3..be0568c722d6 100644
+--- a/drivers/ide/ide-taskfile.c
++++ b/drivers/ide/ide-taskfile.c
+@@ -250,7 +250,7 @@ void ide_pio_bytes(ide_drive_t *drive, struct ide_cmd *cmd,
+ 
+ 		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, struct ide_cmd *cmd,
+ 		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(ide_drive_t *drive,
+ 	}
+ 
+ 	if ((drive->dev_flags & IDE_DFLAG_UNMASK) == 0)
+-		local_irq_disable();
++		local_irq_disable_nort();
+ 
+ 	ide_set_handler(drive, &task_pio_intr, WAIT_WORSTCASE);
+ 
+diff --git a/drivers/infiniband/ulp/ipoib/ipoib_ib.c b/drivers/infiniband/ulp/ipoib/ipoib_ib.c
+index f0e55e47eb54..da5f28c892ca 100644
+--- a/drivers/infiniband/ulp/ipoib/ipoib_ib.c
++++ b/drivers/infiniband/ulp/ipoib/ipoib_ib.c
+@@ -51,8 +51,6 @@ MODULE_PARM_DESC(data_debug_level,
+ 		 "Enable data path debug tracing if > 0");
+ #endif
+ 
+-static DEFINE_MUTEX(pkey_mutex);
+-
+ struct ipoib_ah *ipoib_create_ah(struct net_device *dev,
+ 				 struct ib_pd *pd, struct ib_ah_attr *attr)
+ {
+diff --git a/drivers/infiniband/ulp/ipoib/ipoib_multicast.c b/drivers/infiniband/ulp/ipoib/ipoib_multicast.c
+index 25889311b1e9..7fe9dd26a4da 100644
+--- a/drivers/infiniband/ulp/ipoib/ipoib_multicast.c
++++ b/drivers/infiniband/ulp/ipoib/ipoib_multicast.c
+@@ -883,7 +883,7 @@ void ipoib_mcast_restart_task(struct work_struct *work)
+ 
+ 	ipoib_dbg_mcast(priv, "restarting multicast task\n");
+ 
+-	local_irq_save(flags);
++	local_irq_save_nort(flags);
+ 	netif_addr_lock(dev);
+ 	spin_lock(&priv->lock);
+ 
+@@ -965,7 +965,7 @@ void ipoib_mcast_restart_task(struct work_struct *work)
+ 
+ 	spin_unlock(&priv->lock);
+ 	netif_addr_unlock(dev);
+-	local_irq_restore(flags);
++	local_irq_restore_nort(flags);
+ 
+ 	/*
+ 	 * make sure the in-flight joins have finished before we attempt
+diff --git a/drivers/input/gameport/gameport.c b/drivers/input/gameport/gameport.c
+index 4a2a9e370be7..e970d9afd179 100644
+--- a/drivers/input/gameport/gameport.c
++++ b/drivers/input/gameport/gameport.c
+@@ -91,13 +91,13 @@ static int gameport_measure_speed(struct gameport *gameport)
+ 	tx = ~0;
+ 
+ 	for (i = 0; i < 50; i++) {
+-		local_irq_save(flags);
++		local_irq_save_nort(flags);
+ 		t1 = ktime_get_ns();
+ 		for (t = 0; t < 50; t++)
+ 			gameport_read(gameport);
+ 		t2 = ktime_get_ns();
+ 		t3 = ktime_get_ns();
+-		local_irq_restore(flags);
++		local_irq_restore_nort(flags);
+ 		udelay(i * 10);
+ 		t = (t2 - t1) - (t3 - t2);
+ 		if (t < tx)
+@@ -124,12 +124,12 @@ static int old_gameport_measure_speed(struct gameport *gameport)
+ 	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;
+ 	}
+@@ -148,11 +148,11 @@ static int old_gameport_measure_speed(struct gameport *gameport)
+ 	tx = 1 << 30;
+ 
+ 	for(i = 0; i < 50; i++) {
+-		local_irq_save(flags);
++		local_irq_save_nort(flags);
+ 		t1 = rdtsc();
+ 		for (t = 0; t < 50; t++) gameport_read(gameport);
+ 		t2 = rdtsc();
+-		local_irq_restore(flags);
++		local_irq_restore_nort(flags);
+ 		udelay(i * 10);
+ 		if (t2 - t1 < tx) tx = t2 - t1;
+ 	}
+diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
+index 5efadad4615b..42fc6280729b 100644
+--- a/drivers/iommu/amd_iommu.c
++++ b/drivers/iommu/amd_iommu.c
+@@ -2165,10 +2165,10 @@ static int __attach_device(struct iommu_dev_data *dev_data,
+ 	int ret;
+ 
+ 	/*
+-	 * Must be called with IRQs disabled. Warn here to detect early
+-	 * when its not.
++	 * Must be called with IRQs disabled on a non RT kernel. Warn here to
++	 * detect early when its not.
+ 	 */
+-	WARN_ON(!irqs_disabled());
++	WARN_ON_NONRT(!irqs_disabled());
+ 
+ 	/* lock domain */
+ 	spin_lock(&domain->lock);
+@@ -2331,10 +2331,10 @@ static void __detach_device(struct iommu_dev_data *dev_data)
+ 	struct protection_domain *domain;
+ 
+ 	/*
+-	 * Must be called with IRQs disabled. Warn here to detect early
+-	 * when its not.
++	 * Must be called with IRQs disabled on a non RT kernel. Warn here to
++	 * detect early when its not.
+ 	 */
+-	WARN_ON(!irqs_disabled());
++	WARN_ON_NONRT(!irqs_disabled());
+ 
+ 	if (WARN_ON(!dev_data->domain))
+ 		return;
+diff --git a/drivers/leds/trigger/Kconfig b/drivers/leds/trigger/Kconfig
+index 5bda6a9b56bb..d6286584c807 100644
+--- a/drivers/leds/trigger/Kconfig
++++ b/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
+diff --git a/drivers/md/bcache/Kconfig b/drivers/md/bcache/Kconfig
+index 4d200883c505..98b64ed5cb81 100644
+--- a/drivers/md/bcache/Kconfig
++++ b/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.
+diff --git a/drivers/md/dm.c b/drivers/md/dm.c
+index 3d3ac13287a4..b931c7b85a0b 100644
+--- a/drivers/md/dm.c
++++ b/drivers/md/dm.c
+@@ -2187,7 +2187,7 @@ static void dm_request_fn(struct request_queue *q)
+ 		/* Establish tio->ti before queuing work (map_tio_request) */
+ 		tio->ti = ti;
+ 		queue_kthread_work(&md->kworker, &tio->work);
+-		BUG_ON(!irqs_disabled());
++		BUG_ON_NONRT(!irqs_disabled());
+ 	}
+ }
+ 
+diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
+index e48c262ce032..25b82212e67f 100644
+--- a/drivers/md/raid5.c
++++ b/drivers/md/raid5.c
+@@ -1918,8 +1918,9 @@ static void raid_run_ops(struct stripe_head *sh, unsigned long ops_request)
+ 	struct raid5_percpu *percpu;
+ 	unsigned long cpu;
+ 
+-	cpu = get_cpu();
++	cpu = get_cpu_light();
+ 	percpu = per_cpu_ptr(conf->percpu, cpu);
++	spin_lock(&percpu->lock);
+ 	if (test_bit(STRIPE_OP_BIOFILL, &ops_request)) {
+ 		ops_run_biofill(sh);
+ 		overlap_clear++;
+@@ -1975,7 +1976,8 @@ static void raid_run_ops(struct stripe_head *sh, unsigned long ops_request)
+ 			if (test_and_clear_bit(R5_Overlap, &dev->flags))
+ 				wake_up(&sh->raid_conf->wait_for_overlap);
+ 		}
+-	put_cpu();
++	spin_unlock(&percpu->lock);
++	put_cpu_light();
+ }
+ 
+ static struct stripe_head *alloc_stripe(struct kmem_cache *sc, gfp_t gfp)
+@@ -6415,6 +6417,7 @@ static int raid5_alloc_percpu(struct r5conf *conf)
+ 			       __func__, cpu);
+ 			break;
+ 		}
++		spin_lock_init(&per_cpu_ptr(conf->percpu, cpu)->lock);
+ 	}
+ 	put_online_cpus();
+ 
+diff --git a/drivers/md/raid5.h b/drivers/md/raid5.h
+index 517d4b68a1be..efe91887ecd7 100644
+--- a/drivers/md/raid5.h
++++ b/drivers/md/raid5.h
+@@ -504,6 +504,7 @@ 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 */
+ 		struct flex_array *scribble;   /* space for constructing buffer
+ 					      * lists and performing address
+diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
+index a216b4667742..cea73201112e 100644
+--- a/drivers/misc/Kconfig
++++ b/drivers/misc/Kconfig
+@@ -54,6 +54,7 @@ config AD525X_DPOT_SPI
+ 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
+@@ -69,8 +70,7 @@ 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
+@@ -84,6 +84,15 @@ 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
+@@ -114,6 +123,35 @@ 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
+diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
+index b2fb6dbffcef..22827d5a3ba6 100644
+--- a/drivers/misc/Makefile
++++ b/drivers/misc/Makefile
+@@ -39,6 +39,7 @@ obj-$(CONFIG_C2PORT)		+= c2port/
+ obj-$(CONFIG_HMC6352)		+= hmc6352.o
+ obj-y				+= eeprom/
+ obj-y				+= cb710/
++obj-$(CONFIG_HWLAT_DETECTOR)	+= hwlat_detector.o
+ obj-$(CONFIG_SPEAR13XX_PCIE_GADGET)	+= spear13xx_pcie_gadget.o
+ obj-$(CONFIG_VMWARE_BALLOON)	+= vmw_balloon.o
+ obj-$(CONFIG_ARM_CHARLCD)	+= arm-charlcd.o
+diff --git a/drivers/misc/hwlat_detector.c b/drivers/misc/hwlat_detector.c
+new file mode 100644
+index 000000000000..52f5ad5fd9c0
+--- /dev/null
++++ b/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 (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 (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 (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 (ret)
++		goto out;
++
++	ret = init_debugfs();
++	if (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);
+diff --git a/drivers/mmc/host/jz4740_mmc.c b/drivers/mmc/host/jz4740_mmc.c
+index 03ddf0ecf402..684087db170b 100644
+--- a/drivers/mmc/host/jz4740_mmc.c
++++ b/drivers/mmc/host/jz4740_mmc.c
+@@ -1068,8 +1068,6 @@ static int jz4740_mmc_probe(struct platform_device* pdev)
+ 	jz4740_mmc_clock_disable(host);
+ 	setup_timer(&host->timeout_timer, jz4740_mmc_timeout,
+ 			(unsigned long)host);
+-	/* It is not important when it times out, it just needs to timeout. */
+-	set_timer_slack(&host->timeout_timer, HZ);
+ 
+ 	host->use_dma = true;
+ 	if (host->use_dma && jz4740_mmc_acquire_dma_channels(host) != 0)
+diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
+index 2e6c96845c9a..578ddbeab8ed 100644
+--- a/drivers/mmc/host/mmci.c
++++ b/drivers/mmc/host/mmci.c
+@@ -1155,15 +1155,12 @@ static irqreturn_t mmci_pio_irq(int irq, void *dev_id)
+ 	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;
+@@ -1203,8 +1200,6 @@ static irqreturn_t mmci_pio_irq(int irq, void *dev_id)
+ 
+ 	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.
+diff --git a/drivers/net/ethernet/3com/3c59x.c b/drivers/net/ethernet/3com/3c59x.c
+index d81fceddbe0e..dbcecb8845c6 100644
+--- a/drivers/net/ethernet/3com/3c59x.c
++++ b/drivers/net/ethernet/3com/3c59x.c
+@@ -842,9 +842,9 @@ static void poll_vortex(struct net_device *dev)
+ {
+ 	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
+ 
+@@ -1910,12 +1910,12 @@ static void vortex_tx_timeout(struct net_device *dev)
+ 			 * 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);
+ 		}
+ 	}
+ 
+diff --git a/drivers/net/ethernet/atheros/atl1c/atl1c_main.c b/drivers/net/ethernet/atheros/atl1c/atl1c_main.c
+index d0084d4d1a9b..38370772f5dc 100644
+--- a/drivers/net/ethernet/atheros/atl1c/atl1c_main.c
++++ b/drivers/net/ethernet/atheros/atl1c/atl1c_main.c
+@@ -2217,11 +2217,7 @@ static netdev_tx_t atl1c_xmit_frame(struct sk_buff *skb,
+ 	}
+ 
+ 	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 */
+diff --git a/drivers/net/ethernet/atheros/atl1e/atl1e_main.c b/drivers/net/ethernet/atheros/atl1e/atl1e_main.c
+index 59a03a193e83..734f7a7ad2c3 100644
+--- a/drivers/net/ethernet/atheros/atl1e/atl1e_main.c
++++ b/drivers/net/ethernet/atheros/atl1e/atl1e_main.c
+@@ -1880,8 +1880,7 @@ static netdev_tx_t atl1e_xmit_frame(struct sk_buff *skb,
+ 		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 */
+diff --git a/drivers/net/ethernet/chelsio/cxgb/sge.c b/drivers/net/ethernet/chelsio/cxgb/sge.c
+index 526ea74e82d9..86f467a2c485 100644
+--- a/drivers/net/ethernet/chelsio/cxgb/sge.c
++++ b/drivers/net/ethernet/chelsio/cxgb/sge.c
+@@ -1664,8 +1664,7 @@ static int t1_sge_tx(struct sk_buff *skb, struct adapter *adapter,
+ 	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);
+ 
+diff --git a/drivers/net/ethernet/neterion/s2io.c b/drivers/net/ethernet/neterion/s2io.c
+index 9ba975853ec6..813cfa698160 100644
+--- a/drivers/net/ethernet/neterion/s2io.c
++++ b/drivers/net/ethernet/neterion/s2io.c
+@@ -4084,12 +4084,7 @@ static netdev_tx_t s2io_xmit(struct sk_buff *skb, struct net_device *dev)
+ 			[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)) {
+diff --git a/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c b/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c
+index 3b98b263bad0..ca4add749410 100644
+--- a/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c
++++ b/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c
+@@ -2137,10 +2137,8 @@ static int pch_gbe_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
+ 	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);
+diff --git a/drivers/net/ethernet/realtek/8139too.c b/drivers/net/ethernet/realtek/8139too.c
+index ef668d300800..d987d571fdd6 100644
+--- a/drivers/net/ethernet/realtek/8139too.c
++++ b/drivers/net/ethernet/realtek/8139too.c
+@@ -2229,7 +2229,7 @@ static void rtl8139_poll_controller(struct net_device *dev)
+ 	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);
+ }
+diff --git a/drivers/net/ethernet/tehuti/tehuti.c b/drivers/net/ethernet/tehuti/tehuti.c
+index 14c9d1baa85c..e1a5305418a8 100644
+--- a/drivers/net/ethernet/tehuti/tehuti.c
++++ b/drivers/net/ethernet/tehuti/tehuti.c
+@@ -1629,13 +1629,8 @@ static netdev_tx_t bdx_tx_transmit(struct sk_buff *skb,
+ 	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 */
+diff --git a/drivers/net/ethernet/tile/tilepro.c b/drivers/net/ethernet/tile/tilepro.c
+index 298e059d0498..ea5d774fc89b 100644
+--- a/drivers/net/ethernet/tile/tilepro.c
++++ b/drivers/net/ethernet/tile/tilepro.c
+@@ -588,7 +588,7 @@ static bool tile_net_lepp_free_comps(struct net_device *dev, bool all)
+ static void tile_net_schedule_egress_timer(struct tile_net_cpu *info)
+ {
+ 	if (!info->egress_timer_scheduled) {
+-		mod_timer_pinned(&info->egress_timer, jiffies + 1);
++		mod_timer(&info->egress_timer, jiffies + 1);
+ 		info->egress_timer_scheduled = true;
+ 	}
+ }
+@@ -1004,7 +1004,7 @@ static void tile_net_register(void *dev_ptr)
+ 		BUG();
+ 
+ 	/* Initialize the egress timer. */
+-	init_timer(&info->egress_timer);
++	init_timer_pinned(&info->egress_timer);
+ 	info->egress_timer.data = (long)info;
+ 	info->egress_timer.function = tile_net_handle_egress_timer;
+ 
+diff --git a/drivers/net/rionet.c b/drivers/net/rionet.c
+index 9cfe6aeac84e..a31f4610b493 100644
+--- a/drivers/net/rionet.c
++++ b/drivers/net/rionet.c
+@@ -179,11 +179,7 @@ static int rionet_start_xmit(struct sk_buff *skb, struct net_device *ndev)
+ 	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;
+diff --git a/drivers/net/wireless/intersil/orinoco/orinoco_usb.c b/drivers/net/wireless/intersil/orinoco/orinoco_usb.c
+index f2cd513d54b2..6c0f4c9638a2 100644
+--- a/drivers/net/wireless/intersil/orinoco/orinoco_usb.c
++++ b/drivers/net/wireless/intersil/orinoco/orinoco_usb.c
+@@ -697,7 +697,7 @@ static void ezusb_req_ctx_wait(struct ezusb_priv *upriv,
+ 			while (!ctx->done.done && msecs--)
+ 				udelay(1000);
+ 		} else {
+-			wait_event_interruptible(ctx->done.wait,
++			swait_event_interruptible(ctx->done.wait,
+ 						 ctx->done.done);
+ 		}
+ 		break;
+diff --git a/drivers/pci/access.c b/drivers/pci/access.c
+index d11cdbb8fba3..223bbb9acb03 100644
+--- a/drivers/pci/access.c
++++ b/drivers/pci/access.c
+@@ -672,7 +672,7 @@ void pci_cfg_access_unlock(struct pci_dev *dev)
+ 	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);
+diff --git a/drivers/power/bq27xxx_battery.c b/drivers/power/bq27xxx_battery.c
+index 45f6ebf88df6..e90b3f307e0f 100644
+--- a/drivers/power/bq27xxx_battery.c
++++ b/drivers/power/bq27xxx_battery.c
+@@ -735,11 +735,8 @@ static void bq27xxx_battery_poll(struct work_struct *work)
+ 
+ 	bq27xxx_battery_update(di);
+ 
+-	if (poll_interval > 0) {
+-		/* The timer does not have to be accurate. */
+-		set_timer_slack(&di->work.timer, poll_interval * HZ / 4);
++	if (poll_interval > 0)
+ 		schedule_delayed_work(&di->work, poll_interval * HZ);
+-	}
+ }
+ 
+ /*
+diff --git a/drivers/scsi/fcoe/fcoe.c b/drivers/scsi/fcoe/fcoe.c
+index 0efe7112fc1f..3d232657218d 100644
+--- a/drivers/scsi/fcoe/fcoe.c
++++ b/drivers/scsi/fcoe/fcoe.c
+@@ -1286,7 +1286,7 @@ static void fcoe_percpu_thread_destroy(unsigned int cpu)
+ 	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);
+@@ -1342,7 +1342,7 @@ static void fcoe_percpu_thread_destroy(unsigned int cpu)
+ 			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
+@@ -1566,11 +1566,11 @@ static int fcoe_rcv(struct sk_buff *skb, struct net_device *netdev,
+ static int fcoe_alloc_paged_crc_eof(struct sk_buff *skb, int tlen)
+ {
+ 	struct fcoe_percpu_s *fps;
+-	int rc;
++	int rc, cpu = get_cpu_light();
+ 
+-	fps = &get_cpu_var(fcoe_percpu);
++	fps = &per_cpu(fcoe_percpu, cpu);
+ 	rc = fcoe_get_paged_crc_eof(skb, tlen, fps);
+-	put_cpu_var(fcoe_percpu);
++	put_cpu_light();
+ 
+ 	return rc;
+ }
+@@ -1766,11 +1766,11 @@ static inline int fcoe_filter_frames(struct fc_lport *lport,
+ 		return 0;
+ 	}
+ 
+-	stats = per_cpu_ptr(lport->stats, get_cpu());
++	stats = per_cpu_ptr(lport->stats, get_cpu_light());
+ 	stats->InvalidCRCCount++;
+ 	if (stats->InvalidCRCCount < 5)
+ 		printk(KERN_WARNING "fcoe: dropping frame with CRC error\n");
+-	put_cpu();
++	put_cpu_light();
+ 	return -EINVAL;
+ }
+ 
+@@ -1846,13 +1846,13 @@ static void fcoe_recv_frame(struct sk_buff *skb)
+ 		goto drop;
+ 
+ 	if (!fcoe_filter_frames(lport, fp)) {
+-		put_cpu();
++		put_cpu_light();
+ 		fc_exch_recv(lport, fp);
+ 		return;
+ 	}
+ drop:
+ 	stats->ErrorFrames++;
+-	put_cpu();
++	put_cpu_light();
+ 	kfree_skb(skb);
+ }
+ 
+diff --git a/drivers/scsi/fcoe/fcoe_ctlr.c b/drivers/scsi/fcoe/fcoe_ctlr.c
+index 3e83d485f743..bc69ff93127c 100644
+--- a/drivers/scsi/fcoe/fcoe_ctlr.c
++++ b/drivers/scsi/fcoe/fcoe_ctlr.c
+@@ -831,7 +831,7 @@ static unsigned long fcoe_ctlr_age_fcfs(struct fcoe_ctlr *fip)
+ 
+ 	INIT_LIST_HEAD(&del_list);
+ 
+-	stats = per_cpu_ptr(fip->lp->stats, get_cpu());
++	stats = per_cpu_ptr(fip->lp->stats, get_cpu_light());
+ 
+ 	list_for_each_entry_safe(fcf, next, &fip->fcfs, list) {
+ 		deadline = fcf->time + fcf->fka_period + fcf->fka_period / 2;
+@@ -867,7 +867,7 @@ static unsigned long fcoe_ctlr_age_fcfs(struct fcoe_ctlr *fip)
+ 				sel_time = fcf->time;
+ 		}
+ 	}
+-	put_cpu();
++	put_cpu_light();
+ 
+ 	list_for_each_entry_safe(fcf, next, &del_list, list) {
+ 		/* Removes fcf from current list */
+diff --git a/drivers/scsi/libfc/fc_exch.c b/drivers/scsi/libfc/fc_exch.c
+index 30f9ef0c0d4f..6c686bc01a82 100644
+--- a/drivers/scsi/libfc/fc_exch.c
++++ b/drivers/scsi/libfc/fc_exch.c
+@@ -814,10 +814,10 @@ static struct fc_exch *fc_exch_em_alloc(struct fc_lport *lport,
+ 	}
+ 	memset(ep, 0, sizeof(*ep));
+ 
+-	cpu = get_cpu();
++	cpu = get_cpu_light();
+ 	pool = per_cpu_ptr(mp->pool, cpu);
+ 	spin_lock_bh(&pool->lock);
+-	put_cpu();
++	put_cpu_light();
+ 
+ 	/* peek cache of free slot */
+ 	if (pool->left != FC_XID_UNKNOWN) {
+diff --git a/drivers/scsi/libsas/sas_ata.c b/drivers/scsi/libsas/sas_ata.c
+index 9c706d8c1441..d968ffc79c08 100644
+--- a/drivers/scsi/libsas/sas_ata.c
++++ b/drivers/scsi/libsas/sas_ata.c
+@@ -190,7 +190,7 @@ static unsigned int sas_ata_qc_issue(struct ata_queued_cmd *qc)
+ 	/* TODO: audit callers to ensure they are ready for qc_issue to
+ 	 * unconditionally re-enable interrupts
+ 	 */
+-	local_irq_save(flags);
++	local_irq_save_nort(flags);
+ 	spin_unlock(ap->lock);
+ 
+ 	/* If the device fell off, no sense in issuing commands */
+@@ -255,7 +255,7 @@ static unsigned int sas_ata_qc_issue(struct ata_queued_cmd *qc)
+ 
+  out:
+ 	spin_lock(ap->lock);
+-	local_irq_restore(flags);
++	local_irq_restore_nort(flags);
+ 	return ret;
+ }
+ 
+diff --git a/drivers/scsi/qla2xxx/qla_inline.h b/drivers/scsi/qla2xxx/qla_inline.h
+index edc48f3b8230..ee5c6f9dfb6f 100644
+--- a/drivers/scsi/qla2xxx/qla_inline.h
++++ b/drivers/scsi/qla2xxx/qla_inline.h
+@@ -59,12 +59,12 @@ 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 *
+diff --git a/drivers/thermal/x86_pkg_temp_thermal.c b/drivers/thermal/x86_pkg_temp_thermal.c
+index 7fc919f7da4d..e03fa17b8670 100644
+--- a/drivers/thermal/x86_pkg_temp_thermal.c
++++ b/drivers/thermal/x86_pkg_temp_thermal.c
+@@ -29,6 +29,7 @@
+ #include <linux/pm.h>
+ #include <linux/thermal.h>
+ #include <linux/debugfs.h>
++#include <linux/swork.h>
+ #include <asm/cpu_device_id.h>
+ #include <asm/mce.h>
+ 
+@@ -352,7 +353,7 @@ static void pkg_temp_thermal_threshold_work_fn(struct work_struct *work)
+ 	}
+ }
+ 
+-static int pkg_temp_thermal_platform_thermal_notify(__u64 msr_val)
++static void platform_thermal_notify_work(struct swork_event *event)
+ {
+ 	unsigned long flags;
+ 	int cpu = smp_processor_id();
+@@ -369,7 +370,7 @@ static int pkg_temp_thermal_platform_thermal_notify(__u64 msr_val)
+ 			pkg_work_scheduled[phy_id]) {
+ 		disable_pkg_thres_interrupt();
+ 		spin_unlock_irqrestore(&pkg_work_lock, flags);
+-		return -EINVAL;
++		return;
+ 	}
+ 	pkg_work_scheduled[phy_id] = 1;
+ 	spin_unlock_irqrestore(&pkg_work_lock, flags);
+@@ -378,9 +379,48 @@ static int pkg_temp_thermal_platform_thermal_notify(__u64 msr_val)
+ 	schedule_delayed_work_on(cpu,
+ 				&per_cpu(pkg_temp_thermal_threshold_work, cpu),
+ 				msecs_to_jiffies(notify_delay_ms));
++}
++
++#ifdef CONFIG_PREEMPT_RT_FULL
++static struct swork_event notify_work;
++
++static int thermal_notify_work_init(void)
++{
++	int err;
++
++	err = swork_get();
++	if (err)
++		return err;
++
++	INIT_SWORK(&notify_work, platform_thermal_notify_work);
+ 	return 0;
+ }
+ 
++static void thermal_notify_work_cleanup(void)
++{
++	swork_put();
++}
++
++static int pkg_temp_thermal_platform_thermal_notify(__u64 msr_val)
++{
++	swork_queue(&notify_work);
++	return 0;
++}
++
++#else  /* !CONFIG_PREEMPT_RT_FULL */
++
++static int thermal_notify_work_init(void) { return 0; }
++
++static void thermal_notify_work_cleanup(void) {  }
++
++static int pkg_temp_thermal_platform_thermal_notify(__u64 msr_val)
++{
++	platform_thermal_notify_work(NULL);
++
++	return 0;
++}
++#endif /* CONFIG_PREEMPT_RT_FULL */
++
+ static int find_siblings_cpu(int cpu)
+ {
+ 	int i;
+@@ -584,6 +624,9 @@ static int __init pkg_temp_thermal_init(void)
+ 	if (!x86_match_cpu(pkg_temp_thermal_ids))
+ 		return -ENODEV;
+ 
++	if (!thermal_notify_work_init())
++		return -ENODEV;
++
+ 	spin_lock_init(&pkg_work_lock);
+ 	platform_thermal_package_notify =
+ 			pkg_temp_thermal_platform_thermal_notify;
+@@ -608,7 +651,7 @@ static int __init pkg_temp_thermal_init(void)
+ 	kfree(pkg_work_scheduled);
+ 	platform_thermal_package_notify = NULL;
+ 	platform_thermal_package_rate_control = NULL;
+-
++	thermal_notify_work_cleanup();
+ 	return -ENODEV;
+ }
+ 
+@@ -633,6 +676,7 @@ static void __exit pkg_temp_thermal_exit(void)
+ 	mutex_unlock(&phy_dev_list_mutex);
+ 	platform_thermal_package_notify = NULL;
+ 	platform_thermal_package_rate_control = NULL;
++	thermal_notify_work_cleanup();
+ 	for_each_online_cpu(i)
+ 		cancel_delayed_work_sync(
+ 			&per_cpu(pkg_temp_thermal_threshold_work, i));
+diff --git a/drivers/tty/metag_da.c b/drivers/tty/metag_da.c
+index 9325262289f9..25ccef2fe748 100644
+--- a/drivers/tty/metag_da.c
++++ b/drivers/tty/metag_da.c
+@@ -323,12 +323,12 @@ static void dashtty_timer(unsigned long ignored)
+ 	if (channel >= 0)
+ 		fetch_data(channel);
+ 
+-	mod_timer_pinned(&poll_timer, jiffies + DA_TTY_POLL);
++	mod_timer(&poll_timer, jiffies + DA_TTY_POLL);
+ }
+ 
+ static void add_poll_timer(struct timer_list *poll_timer)
+ {
+-	setup_timer(poll_timer, dashtty_timer, 0);
++	setup_pinned_timer(poll_timer, dashtty_timer, 0);
+ 	poll_timer->expires = jiffies + DA_TTY_POLL;
+ 
+ 	/*
+diff --git a/drivers/tty/mips_ejtag_fdc.c b/drivers/tty/mips_ejtag_fdc.c
+index a119176a1855..234123b0c642 100644
+--- a/drivers/tty/mips_ejtag_fdc.c
++++ b/drivers/tty/mips_ejtag_fdc.c
+@@ -689,7 +689,7 @@ static void mips_ejtag_fdc_tty_timer(unsigned long opaque)
+ 
+ 	mips_ejtag_fdc_handle(priv);
+ 	if (!priv->removing)
+-		mod_timer_pinned(&priv->poll_timer, jiffies + FDC_TTY_POLL);
++		mod_timer(&priv->poll_timer, jiffies + FDC_TTY_POLL);
+ }
+ 
+ /* TTY Port operations */
+@@ -1002,7 +1002,7 @@ static int mips_ejtag_fdc_tty_probe(struct mips_cdmm_device *dev)
+ 		raw_spin_unlock_irq(&priv->lock);
+ 	} else {
+ 		/* If we didn't get an usable IRQ, poll instead */
+-		setup_timer(&priv->poll_timer, mips_ejtag_fdc_tty_timer,
++		setup_pinned_timer(&priv->poll_timer, mips_ejtag_fdc_tty_timer,
+ 			    (unsigned long)priv);
+ 		priv->poll_timer.expires = jiffies + FDC_TTY_POLL;
+ 		/*
+diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
+index 2f4f5ee651db..6ea6a3134e16 100644
+--- a/drivers/tty/serial/8250/8250_core.c
++++ b/drivers/tty/serial/8250/8250_core.c
+@@ -58,7 +58,16 @@ static struct uart_driver serial8250_reg;
+ 
+ static unsigned int skip_txen_test; /* force skip of txen test at init time */
+ 
+-#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
+ 
+ #include <asm/serial.h>
+ /*
+diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
+index 00ad2637b08c..c9f6a4937b23 100644
+--- a/drivers/tty/serial/8250/8250_port.c
++++ b/drivers/tty/serial/8250/8250_port.c
+@@ -35,6 +35,7 @@
+ #include <linux/nmi.h>
+ #include <linux/mutex.h>
+ #include <linux/slab.h>
++#include <linux/kdb.h>
+ #include <linux/uaccess.h>
+ #include <linux/pm_runtime.h>
+ #include <linux/timer.h>
+@@ -3092,9 +3093,9 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,
+ 
+ 	serial8250_rpm_get(up);
+ 
+-	if (port->sysrq)
++	if (port->sysrq || oops_in_progress)
+ 		locked = 0;
+-	else if (oops_in_progress)
++	else if (in_kdb_printk())
+ 		locked = spin_trylock_irqsave(&port->lock, flags);
+ 	else
+ 		spin_lock_irqsave(&port->lock, flags);
+diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
+index 7c198e0a3178..a26b81c4aae6 100644
+--- a/drivers/tty/serial/amba-pl011.c
++++ b/drivers/tty/serial/amba-pl011.c
+@@ -2166,13 +2166,19 @@ pl011_console_write(struct console *co, const char *s, unsigned int count)
+ 
+ 	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
+@@ -2196,8 +2202,7 @@ pl011_console_write(struct console *co, const char *s, unsigned int count)
+ 		pl011_write(old_cr, uap, REG_CR);
+ 
+ 	if (locked)
+-		spin_unlock(&uap->port.lock);
+-	local_irq_restore(flags);
++		spin_unlock_irqrestore(&uap->port.lock, flags);
+ 
+ 	clk_disable(uap->clk);
+ }
+diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
+index a2a529994ba5..0ee7c4c518df 100644
+--- a/drivers/tty/serial/omap-serial.c
++++ b/drivers/tty/serial/omap-serial.c
+@@ -1257,13 +1257,10 @@ serial_omap_console_write(struct console *co, const char *s,
+ 
+ 	pm_runtime_get_sync(up->dev);
+ 
+-	local_irq_save(flags);
+-	if (up->port.sysrq)
+-		locked = 0;
+-	else if (oops_in_progress)
+-		locked = spin_trylock(&up->port.lock);
++	if (up->port.sysrq || oops_in_progress)
++		locked = spin_trylock_irqsave(&up->port.lock, flags);
+ 	else
+-		spin_lock(&up->port.lock);
++		spin_lock_irqsave(&up->port.lock, flags);
+ 
+ 	/*
+ 	 * First save the IER then disable the interrupts
+@@ -1292,8 +1289,7 @@ serial_omap_console_write(struct console *co, const char *s,
+ 	pm_runtime_mark_last_busy(up->dev);
+ 	pm_runtime_put_autosuspend(up->dev);
+ 	if (locked)
+-		spin_unlock(&up->port.lock);
+-	local_irq_restore(flags);
++		spin_unlock_irqrestore(&up->port.lock, flags);
+ }
+ 
+ static int __init
+diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
+index 025a4264430e..73d46e2155a9 100644
+--- a/drivers/tty/serial/sc16is7xx.c
++++ b/drivers/tty/serial/sc16is7xx.c
+@@ -1251,7 +1251,7 @@ static int sc16is7xx_probe(struct device *dev,
+ 
+ 	/* Setup interrupt */
+ 	ret = devm_request_irq(dev, irq, sc16is7xx_irq,
+-			       IRQF_ONESHOT | flags, dev_name(dev), s);
++			       flags, dev_name(dev), s);
+ 	if (!ret)
+ 		return 0;
+ 
+diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
+index 2d107d0f61b0..28a5cb87289a 100644
+--- a/drivers/usb/core/hcd.c
++++ b/drivers/usb/core/hcd.c
+@@ -1759,9 +1759,9 @@ static void __usb_hcd_giveback_urb(struct urb *urb)
+ 	 * 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);
+ 
+ 	usb_anchor_resume_wakeups(anchor);
+ 	atomic_dec(&urb->use_count);
+diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
+index 73515d54e1cc..78a9351b6226 100644
+--- a/drivers/usb/gadget/function/f_fs.c
++++ b/drivers/usb/gadget/function/f_fs.c
+@@ -1393,7 +1393,7 @@ static void ffs_data_put(struct ffs_data *ffs)
+ 		pr_info("%s(): freeing\n", __func__);
+ 		ffs_data_clear(ffs);
+ 		BUG_ON(waitqueue_active(&ffs->ev.waitq) ||
+-		       waitqueue_active(&ffs->ep0req_completion.wait));
++		       swait_active(&ffs->ep0req_completion.wait));
+ 		kfree(ffs->dev_name);
+ 		kfree(ffs);
+ 	}
+diff --git a/drivers/usb/gadget/legacy/inode.c b/drivers/usb/gadget/legacy/inode.c
+index aa3707bdebb4..665654412e4f 100644
+--- a/drivers/usb/gadget/legacy/inode.c
++++ b/drivers/usb/gadget/legacy/inode.c
+@@ -346,7 +346,7 @@ ep_io (struct ep_data *epdata, void *buf, unsigned len)
+ 	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)) {
+@@ -355,7 +355,7 @@ ep_io (struct ep_data *epdata, void *buf, unsigned len)
+ 				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 {
+diff --git a/drivers/usb/host/ohci-hcd.c b/drivers/usb/host/ohci-hcd.c
+index 04dcedfdebf8..86919ec47163 100644
+--- a/drivers/usb/host/ohci-hcd.c
++++ b/drivers/usb/host/ohci-hcd.c
+@@ -500,7 +500,6 @@ static int ohci_init (struct ohci_hcd *ohci)
+ 
+ 	setup_timer(&ohci->io_watchdog, io_watchdog_func,
+ 			(unsigned long) ohci);
+-	set_timer_slack(&ohci->io_watchdog, msecs_to_jiffies(20));
+ 
+ 	ohci->hcca = dma_alloc_coherent (hcd->self.controller,
+ 			sizeof(*ohci->hcca), &ohci->hcca_dma, GFP_KERNEL);
+diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
+index 327280535848..7901a685b8de 100644
+--- a/drivers/usb/host/xhci.c
++++ b/drivers/usb/host/xhci.c
+@@ -490,8 +490,6 @@ static void compliance_mode_recovery_timer_init(struct xhci_hcd *xhci)
+ 	xhci->comp_mode_recovery_timer.expires = jiffies +
+ 			msecs_to_jiffies(COMP_MODE_RCVRY_MSECS);
+ 
+-	set_timer_slack(&xhci->comp_mode_recovery_timer,
+-			msecs_to_jiffies(COMP_MODE_RCVRY_MSECS));
+ 	add_timer(&xhci->comp_mode_recovery_timer);
+ 	xhci_dbg_trace(xhci, trace_xhci_dbg_quirks,
+ 			"Compliance mode recovery timer initialized");
+diff --git a/fs/aio.c b/fs/aio.c
+index 155f84253f33..dd8d6f234a0b 100644
+--- a/fs/aio.c
++++ b/fs/aio.c
+@@ -40,6 +40,7 @@
+ #include <linux/ramfs.h>
+ #include <linux/percpu-refcount.h>
+ #include <linux/mount.h>
++#include <linux/swork.h>
+ 
+ #include <asm/kmap_types.h>
+ #include <asm/uaccess.h>
+@@ -115,7 +116,7 @@ struct kioctx {
+ 	struct page		**ring_pages;
+ 	long			nr_pages;
+ 
+-	struct work_struct	free_work;
++	struct swork_event	free_work;
+ 
+ 	/*
+ 	 * signals when all in-flight requests are done
+@@ -253,6 +254,7 @@ static int __init aio_setup(void)
+ 		.mount		= aio_mount,
+ 		.kill_sb	= kill_anon_super,
+ 	};
++	BUG_ON(swork_get());
+ 	aio_mnt = kern_mount(&aio_fs);
+ 	if (IS_ERR(aio_mnt))
+ 		panic("Failed to create aio fs mount.");
+@@ -568,9 +570,9 @@ static int kiocb_cancel(struct aio_kiocb *kiocb)
+ 	return cancel(&kiocb->common);
+ }
+ 
+-static void free_ioctx(struct work_struct *work)
++static void free_ioctx(struct swork_event *sev)
+ {
+-	struct kioctx *ctx = container_of(work, struct kioctx, free_work);
++	struct kioctx *ctx = container_of(sev, struct kioctx, free_work);
+ 
+ 	pr_debug("freeing %p\n", ctx);
+ 
+@@ -589,8 +591,8 @@ static void free_ioctx_reqs(struct percpu_ref *ref)
+ 	if (ctx->rq_wait && atomic_dec_and_test(&ctx->rq_wait->count))
+ 		complete(&ctx->rq_wait->comp);
+ 
+-	INIT_WORK(&ctx->free_work, free_ioctx);
+-	schedule_work(&ctx->free_work);
++	INIT_SWORK(&ctx->free_work, free_ioctx);
++	swork_queue(&ctx->free_work);
+ }
+ 
+ /*
+@@ -598,9 +600,9 @@ static void free_ioctx_reqs(struct percpu_ref *ref)
+  * and ctx->users has dropped to 0, so we know no more kiocbs can be submitted -
+  * now it's safe to cancel any that need to be.
+  */
+-static void free_ioctx_users(struct percpu_ref *ref)
++static void free_ioctx_users_work(struct swork_event *sev)
+ {
+-	struct kioctx *ctx = container_of(ref, struct kioctx, users);
++	struct kioctx *ctx = container_of(sev, struct kioctx, free_work);
+ 	struct aio_kiocb *req;
+ 
+ 	spin_lock_irq(&ctx->ctx_lock);
+@@ -619,6 +621,14 @@ static void free_ioctx_users(struct percpu_ref *ref)
+ 	percpu_ref_put(&ctx->reqs);
+ }
+ 
++static void free_ioctx_users(struct percpu_ref *ref)
++{
++	struct kioctx *ctx = container_of(ref, struct kioctx, users);
++
++	INIT_SWORK(&ctx->free_work, free_ioctx_users_work);
++	swork_queue(&ctx->free_work);
++}
++
+ static int ioctx_add_table(struct kioctx *ctx, struct mm_struct *mm)
+ {
+ 	unsigned i, new_nr;
+diff --git a/fs/autofs4/autofs_i.h b/fs/autofs4/autofs_i.h
+index f0d268b97d19..dfbccaefae5d 100644
+--- a/fs/autofs4/autofs_i.h
++++ b/fs/autofs4/autofs_i.h
+@@ -30,6 +30,7 @@
+ #include <linux/sched.h>
+ #include <linux/mount.h>
+ #include <linux/namei.h>
++#include <linux/delay.h>
+ #include <asm/current.h>
+ #include <linux/uaccess.h>
+ 
+diff --git a/fs/autofs4/expire.c b/fs/autofs4/expire.c
+index 9510d8d2e9cd..893c87d4f5a9 100644
+--- a/fs/autofs4/expire.c
++++ b/fs/autofs4/expire.c
+@@ -148,7 +148,7 @@ static struct dentry *get_next_positive_dentry(struct dentry *prev,
+ 			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);
+diff --git a/fs/buffer.c b/fs/buffer.c
+index af0d9a82a8ed..370df12f9df7 100644
+--- a/fs/buffer.c
++++ b/fs/buffer.c
+@@ -300,8 +300,7 @@ static void end_buffer_async_read(struct buffer_head *bh, int uptodate)
+ 	 * 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;
+@@ -314,8 +313,7 @@ static void end_buffer_async_read(struct buffer_head *bh, int uptodate)
+ 		}
+ 		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
+@@ -327,9 +325,7 @@ static void end_buffer_async_read(struct buffer_head *bh, int uptodate)
+ 	return;
+ 
+ still_busy:
+-	bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
+-	local_irq_restore(flags);
+-	return;
++	bh_uptodate_unlock_irqrestore(first, flags);
+ }
+ 
+ /*
+@@ -357,8 +353,7 @@ void end_buffer_async_write(struct buffer_head *bh, int uptodate)
+ 	}
+ 
+ 	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);
+@@ -370,15 +365,12 @@ void end_buffer_async_write(struct buffer_head *bh, int uptodate)
+ 		}
+ 		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);
+ 
+@@ -3314,6 +3306,7 @@ struct buffer_head *alloc_buffer_head(gfp_t gfp_flags)
+ 	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();
+diff --git a/fs/dcache.c b/fs/dcache.c
+index 44008e3fafc4..abc87dc3b8bf 100644
+--- a/fs/dcache.c
++++ b/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>
+@@ -578,7 +579,7 @@ static struct dentry *dentry_kill(struct dentry *dentry)
+ 
+ failed:
+ 	spin_unlock(&dentry->d_lock);
+-	cpu_relax();
++	cpu_chill();
+ 	return dentry; /* try again with same dentry */
+ }
+ 
+@@ -2316,7 +2317,7 @@ void d_delete(struct dentry * dentry)
+ 	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;
+diff --git a/fs/eventpoll.c b/fs/eventpoll.c
+index 8a74a2a52e0f..b92f9110a641 100644
+--- a/fs/eventpoll.c
++++ b/fs/eventpoll.c
+@@ -510,12 +510,12 @@ static int ep_poll_wakeup_proc(void *priv, void *cookie, int call_nests)
+  */
+ 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)
+diff --git a/fs/exec.c b/fs/exec.c
+index c4010b8207a1..879fd0772b78 100644
+--- a/fs/exec.c
++++ b/fs/exec.c
+@@ -961,12 +961,14 @@ static int exec_mmap(struct mm_struct *mm)
+ 		}
+ 	}
+ 	task_lock(tsk);
++	preempt_disable_rt();
+ 	active_mm = tsk->active_mm;
+ 	tsk->mm = mm;
+ 	tsk->active_mm = mm;
+ 	activate_mm(active_mm, mm);
+ 	tsk->mm->vmacache_seqnum = 0;
+ 	vmacache_flush(tsk);
++	preempt_enable_rt();
+ 	task_unlock(tsk);
+ 	if (old_mm) {
+ 		up_read(&old_mm->mmap_sem);
+diff --git a/fs/jbd2/checkpoint.c b/fs/jbd2/checkpoint.c
+index 684996c8a3a4..6e18a06aaabe 100644
+--- a/fs/jbd2/checkpoint.c
++++ b/fs/jbd2/checkpoint.c
+@@ -116,6 +116,8 @@ void __jbd2_log_wait_for_space(journal_t *journal)
+ 	nblocks = jbd2_space_needed(journal);
+ 	while (jbd2_log_space_left(journal) < nblocks) {
+ 		write_unlock(&journal->j_state_lock);
++		if (current->plug)
++			io_schedule();
+ 		mutex_lock(&journal->j_checkpoint_mutex);
+ 
+ 		/*
+diff --git a/fs/namespace.c b/fs/namespace.c
+index 783004af5707..ff8492bd3de7 100644
+--- a/fs/namespace.c
++++ b/fs/namespace.c
+@@ -14,6 +14,7 @@
+ #include <linux/mnt_namespace.h>
+ #include <linux/user_namespace.h>
+ #include <linux/namei.h>
++#include <linux/delay.h>
+ #include <linux/security.h>
+ #include <linux/idr.h>
+ #include <linux/init.h>		/* init_rootfs */
+@@ -353,8 +354,11 @@ 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
+diff --git a/fs/ntfs/aops.c b/fs/ntfs/aops.c
+index 97768a1379f2..6d2ea1af146b 100644
+--- a/fs/ntfs/aops.c
++++ b/fs/ntfs/aops.c
+@@ -92,13 +92,13 @@ static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate)
+ 			ofs = 0;
+ 			if (file_ofs < init_size)
+ 				ofs = init_size - file_ofs;
+-			local_irq_save(flags);
++			local_irq_save_nort(flags);
+ 			kaddr = kmap_atomic(page);
+ 			memset(kaddr + bh_offset(bh) + ofs, 0,
+ 					bh->b_size - ofs);
+ 			flush_dcache_page(page);
+ 			kunmap_atomic(kaddr);
+-			local_irq_restore(flags);
++			local_irq_restore_nort(flags);
+ 		}
+ 	} else {
+ 		clear_buffer_uptodate(bh);
+@@ -107,8 +107,7 @@ static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate)
+ 				"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;
+@@ -123,8 +122,7 @@ static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate)
+ 		}
+ 		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
+@@ -145,13 +143,13 @@ static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate)
+ 		recs = PAGE_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);
+@@ -159,9 +157,7 @@ static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate)
+ 	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);
+ }
+ 
+ /**
+diff --git a/fs/timerfd.c b/fs/timerfd.c
+index 053818dd6c18..c4bc14fe0085 100644
+--- a/fs/timerfd.c
++++ b/fs/timerfd.c
+@@ -450,7 +450,10 @@ static int do_timerfd_settime(int ufd, int flags,
+ 				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);
+ 	}
+ 
+ 	/*
+diff --git a/include/acpi/platform/aclinux.h b/include/acpi/platform/aclinux.h
+index 45c2d6528829..794eead4f075 100644
+--- a/include/acpi/platform/aclinux.h
++++ b/include/acpi/platform/aclinux.h
+@@ -127,6 +127,7 @@
+ 
+ #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
+ 
+ /* Use native linux version of acpi_os_allocate_zeroed */
+@@ -145,6 +146,20 @@
+ #define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_get_thread_id
+ #define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_create_lock
+ 
++#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)
++
++
+ /*
+  * OSL interfaces used by debugger/disassembler
+  */
+diff --git a/include/asm-generic/bug.h b/include/asm-generic/bug.h
+index 6f96247226a4..fa53a21263c2 100644
+--- a/include/asm-generic/bug.h
++++ b/include/asm-generic/bug.h
+@@ -215,6 +215,20 @@ void __warn(const char *file, int line, void *caller, unsigned taint,
+ # 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
+diff --git a/include/asm-generic/preempt.h b/include/asm-generic/preempt.h
+index 5d8ffa3e6f8c..c1cde3577551 100644
+--- a/include/asm-generic/preempt.h
++++ b/include/asm-generic/preempt.h
+@@ -7,10 +7,10 @@
+ 
+ static __always_inline int preempt_count(void)
+ {
+-	return current_thread_info()->preempt_count;
++	return READ_ONCE(current_thread_info()->preempt_count);
+ }
+ 
+-static __always_inline int *preempt_count_ptr(void)
++static __always_inline volatile int *preempt_count_ptr(void)
+ {
+ 	return &current_thread_info()->preempt_count;
+ }
+diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
+index 9ac9799b702b..05fc2492131a 100644
+--- a/include/linux/blk-mq.h
++++ b/include/linux/blk-mq.h
+@@ -218,6 +218,7 @@ static inline u16 blk_mq_unique_tag_to_tag(u32 unique_tag)
+ 
+ struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *, const int ctx_index);
+ struct blk_mq_hw_ctx *blk_mq_alloc_single_hw_queue(struct blk_mq_tag_set *, unsigned int, int);
++void __blk_mq_complete_request_remote_work(struct work_struct *work);
+ 
+ int blk_mq_request_started(struct request *rq);
+ void blk_mq_start_request(struct request *rq);
+diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
+index 669e419d6234..6678028d8508 100644
+--- a/include/linux/blkdev.h
++++ b/include/linux/blkdev.h
+@@ -90,6 +90,7 @@ struct request {
+ 	struct list_head queuelist;
+ 	union {
+ 		struct call_single_data csd;
++		struct work_struct work;
+ 		unsigned long fifo_time;
+ 	};
+ 
+@@ -457,7 +458,7 @@ struct request_queue {
+ 	struct throtl_data *td;
+ #endif
+ 	struct rcu_head		rcu_head;
+-	wait_queue_head_t	mq_freeze_wq;
++	struct swait_queue_head	mq_freeze_wq;
+ 	struct percpu_ref	q_usage_counter;
+ 	struct list_head	all_q_node;
+ 
+diff --git a/include/linux/bottom_half.h b/include/linux/bottom_half.h
+index 8fdcb783197d..d07dbeec7bc1 100644
+--- a/include/linux/bottom_half.h
++++ b/include/linux/bottom_half.h
+@@ -3,6 +3,39 @@
+ 
+ #include <linux/preempt.h>
+ 
++#ifdef CONFIG_PREEMPT_RT_FULL
++
++extern void __local_bh_disable(void);
++extern void _local_bh_enable(void);
++extern void __local_bh_enable(void);
++
++static inline void local_bh_disable(void)
++{
++	__local_bh_disable();
++}
++
++static inline void __local_bh_disable_ip(unsigned long ip, unsigned int cnt)
++{
++	__local_bh_disable();
++}
++
++static inline void local_bh_enable(void)
++{
++	__local_bh_enable();
++}
++
++static inline void __local_bh_enable_ip(unsigned long ip, unsigned int cnt)
++{
++	__local_bh_enable();
++}
++
++static inline void local_bh_enable_ip(unsigned long ip)
++{
++	__local_bh_enable();
++}
++
++#else
++
+ #ifdef CONFIG_TRACE_IRQFLAGS
+ extern void __local_bh_disable_ip(unsigned long ip, unsigned int cnt);
+ #else
+@@ -30,5 +63,6 @@ static inline void local_bh_enable(void)
+ {
+ 	__local_bh_enable_ip(_THIS_IP_, SOFTIRQ_DISABLE_OFFSET);
+ }
++#endif
+ 
+ #endif /* _LINUX_BH_H */
+diff --git a/include/linux/buffer_head.h b/include/linux/buffer_head.h
+index d48daa3f6f20..91588cd809ce 100644
+--- a/include/linux/buffer_head.h
++++ b/include/linux/buffer_head.h
+@@ -75,8 +75,50 @@ 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 IS_ENABLED(CONFIG_JBD2)
++	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 IS_ENABLED(CONFIG_JBD2)
++	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.
+diff --git a/include/linux/cgroup-defs.h b/include/linux/cgroup-defs.h
+index 5b17de62c962..56027cc01a56 100644
+--- a/include/linux/cgroup-defs.h
++++ b/include/linux/cgroup-defs.h
+@@ -16,6 +16,7 @@
+ #include <linux/percpu-refcount.h>
+ #include <linux/percpu-rwsem.h>
+ #include <linux/workqueue.h>
++#include <linux/swork.h>
+ 
+ #ifdef CONFIG_CGROUPS
+ 
+@@ -137,6 +138,7 @@ struct cgroup_subsys_state {
+ 	/* percpu_ref killing and RCU release */
+ 	struct rcu_head rcu_head;
+ 	struct work_struct destroy_work;
++	struct swork_event destroy_swork;
+ };
+ 
+ /*
+diff --git a/include/linux/completion.h b/include/linux/completion.h
+index 5d5aaae3af43..3bca1590e29f 100644
+--- a/include/linux/completion.h
++++ b/include/linux/completion.h
+@@ -7,8 +7,7 @@
+  * Atomic wait-for-completion handler data structures.
+  * See kernel/sched/completion.c for details.
+  */
+-
+-#include <linux/wait.h>
++#include <linux/swait.h>
+ 
+ /*
+  * struct completion - structure used to maintain state for a "completion"
+@@ -24,11 +23,11 @@
+  */
+ struct completion {
+ 	unsigned int done;
+-	wait_queue_head_t wait;
++	struct swait_queue_head wait;
+ };
+ 
+ #define COMPLETION_INITIALIZER(work) \
+-	{ 0, __WAIT_QUEUE_HEAD_INITIALIZER((work).wait) }
++	{ 0, __SWAIT_QUEUE_HEAD_INITIALIZER((work).wait) }
+ 
+ #define COMPLETION_INITIALIZER_ONSTACK(work) \
+ 	({ init_completion(&work); work; })
+@@ -73,7 +72,7 @@ struct completion {
+ static inline void init_completion(struct completion *x)
+ {
+ 	x->done = 0;
+-	init_waitqueue_head(&x->wait);
++	init_swait_queue_head(&x->wait);
+ }
+ 
+ /**
+diff --git a/include/linux/cpu.h b/include/linux/cpu.h
+index f9b1fab4388a..d4cc4818d13e 100644
+--- a/include/linux/cpu.h
++++ b/include/linux/cpu.h
+@@ -230,6 +230,8 @@ 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 __hotcpu_notifier(fn, pri)	__cpu_notifier(fn, pri)
+ #define register_hotcpu_notifier(nb)	register_cpu_notifier(nb)
+@@ -247,6 +249,8 @@ 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)
+ #define __hotcpu_notifier(fn, pri)	do { (void)(fn); } while (0)
+ /* These aren't inline functions due to a GCC bug. */
+diff --git a/include/linux/delay.h b/include/linux/delay.h
+index a6ecb34cf547..37caab306336 100644
+--- a/include/linux/delay.h
++++ b/include/linux/delay.h
+@@ -52,4 +52,10 @@ static inline void ssleep(unsigned int seconds)
+ 	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) */
+diff --git a/include/linux/highmem.h b/include/linux/highmem.h
+index bb3f3297062a..a117a33ef72c 100644
+--- a/include/linux/highmem.h
++++ b/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>
+ 
+@@ -65,7 +66,7 @@ static inline void kunmap(struct page *page)
+ 
+ static inline void *kmap_atomic(struct page *page)
+ {
+-	preempt_disable();
++	preempt_disable_nort();
+ 	pagefault_disable();
+ 	return page_address(page);
+ }
+@@ -74,7 +75,7 @@ static inline void *kmap_atomic(struct page *page)
+ static inline void __kunmap_atomic(void *addr)
+ {
+ 	pagefault_enable();
+-	preempt_enable();
++	preempt_enable_nort();
+ }
+ 
+ #define kmap_atomic_pfn(pfn)	kmap_atomic(pfn_to_page(pfn))
+@@ -86,32 +87,51 @@ static inline void __kunmap_atomic(void *addr)
+ 
+ #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
+ }
+ 
+diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
+index c98c6539e2c2..573ffbce6ab7 100644
+--- a/include/linux/hrtimer.h
++++ b/include/linux/hrtimer.h
+@@ -87,6 +87,9 @@ enum hrtimer_restart {
+  * @function:	timer expiry callback function
+  * @base:	pointer to the timer base (per cpu and per clock)
+  * @state:	state information (See bit values above)
++ * @cb_entry:	list entry to defer timers from hardirq context
++ * @irqsafe:	timer can run in hardirq context
++ * @praecox:	timer expiry time if expired at the time of programming
+  * @is_rel:	Set if the timer was armed relative
+  * @start_pid:  timer statistics field to store the pid of the task which
+  *		started the timer
+@@ -103,6 +106,11 @@ struct hrtimer {
+ 	enum hrtimer_restart		(*function)(struct hrtimer *);
+ 	struct hrtimer_clock_base	*base;
+ 	u8				state;
++	struct list_head		cb_entry;
++	int				irqsafe;
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++	ktime_t				praecox;
++#endif
+ 	u8				is_rel;
+ #ifdef CONFIG_TIMER_STATS
+ 	int				start_pid;
+@@ -123,11 +131,7 @@ struct hrtimer_sleeper {
+ 	struct task_struct *task;
+ };
+ 
+-#ifdef CONFIG_64BIT
+ # define HRTIMER_CLOCK_BASE_ALIGN	64
+-#else
+-# define HRTIMER_CLOCK_BASE_ALIGN	32
+-#endif
+ 
+ /**
+  * struct hrtimer_clock_base - the timer base for a specific clock
+@@ -136,6 +140,7 @@ struct hrtimer_sleeper {
+  *			timer to a base on another cpu.
+  * @clockid:		clock id for per_cpu support
+  * @active:		red black tree root node for the active timers
++ * @expired:		list head for deferred timers.
+  * @get_time:		function to retrieve the current time of the clock
+  * @offset:		offset of this clock to the monotonic base
+  */
+@@ -144,6 +149,7 @@ struct hrtimer_clock_base {
+ 	int			index;
+ 	clockid_t		clockid;
+ 	struct timerqueue_head	active;
++	struct list_head	expired;
+ 	ktime_t			(*get_time)(void);
+ 	ktime_t			offset;
+ } __attribute__((__aligned__(HRTIMER_CLOCK_BASE_ALIGN)));
+@@ -187,6 +193,7 @@ struct hrtimer_cpu_base {
+ 	raw_spinlock_t			lock;
+ 	seqcount_t			seq;
+ 	struct hrtimer			*running;
++	struct hrtimer			*running_soft;
+ 	unsigned int			cpu;
+ 	unsigned int			active_bases;
+ 	unsigned int			clock_was_set_seq;
+@@ -203,6 +210,9 @@ struct hrtimer_cpu_base {
+ 	unsigned int			nr_hangs;
+ 	unsigned int			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];
+ } ____cacheline_aligned;
+ 
+@@ -412,6 +422,13 @@ static inline void hrtimer_restart(struct hrtimer *timer)
+ 	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, bool adjust);
+ 
+@@ -436,7 +453,7 @@ static inline int hrtimer_is_queued(struct hrtimer *timer)
+  * Helper function to check, whether the timer is running the callback
+  * function
+  */
+-static inline int hrtimer_callback_running(struct hrtimer *timer)
++static inline int hrtimer_callback_running(const struct hrtimer *timer)
+ {
+ 	return timer->base->cpu_base->running == timer;
+ }
+diff --git a/include/linux/idr.h b/include/linux/idr.h
+index 083d61e92706..5899796f50cb 100644
+--- a/include/linux/idr.h
++++ b/include/linux/idr.h
+@@ -95,10 +95,14 @@ bool idr_is_empty(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
+diff --git a/include/linux/init_task.h b/include/linux/init_task.h
+index f2cb8d45513d..60fadde71a44 100644
+--- a/include/linux/init_task.h
++++ b/include/linux/init_task.h
+@@ -148,6 +148,12 @@ 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_seqcount = SEQCNT_ZERO(tsk.vtime_seqcount),	\
+@@ -239,6 +245,7 @@ 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),		\
+diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
+index 9fcabeb07787..e6f7e42c8253 100644
+--- a/include/linux/interrupt.h
++++ b/include/linux/interrupt.h
+@@ -61,6 +61,7 @@
+  *                interrupt handler after suspending interrupts. For system
+  *                wakeup devices users need to implement wakeup detection in
+  *                their interrupt handlers.
++ * IRQF_NO_SOFTIRQ_CALL - Do not process softirqs in the irq thread context (RT)
+  */
+ #define IRQF_SHARED		0x00000080
+ #define IRQF_PROBE_SHARED	0x00000100
+@@ -74,6 +75,7 @@
+ #define IRQF_NO_THREAD		0x00010000
+ #define IRQF_EARLY_RESUME	0x00020000
+ #define IRQF_COND_SUSPEND	0x00040000
++#define IRQF_NO_SOFTIRQ_CALL	0x00080000
+ 
+ #define IRQF_TIMER		(__IRQF_TIMER | IRQF_NO_SUSPEND | IRQF_NO_THREAD)
+ 
+@@ -196,7 +198,7 @@ extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id);
+ #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);
+@@ -217,6 +219,7 @@ extern void resume_device_irqs(void);
+  * @irq:		Interrupt to which notification applies
+  * @kref:		Reference count, for internal use
+  * @work:		Work item, for internal use
++ * @list:		List item for deferred callbacks
+  * @notify:		Function to be called on change.  This will be
+  *			called in process context.
+  * @release:		Function to be called on release.  This will be
+@@ -228,6 +231,7 @@ 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);
+ };
+@@ -390,9 +394,13 @@ extern int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
+ 				 bool state);
+ 
+ #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
+@@ -449,9 +457,10 @@ 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(); }
+ #ifdef __ARCH_HAS_DO_SOFTIRQ
+ void do_softirq_own_stack(void);
+ #else
+@@ -460,13 +469,25 @@ static inline void do_softirq_own_stack(void)
+ 	__do_softirq();
+ }
+ #endif
++#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);
++#ifdef CONFIG_PREEMPT_RT_FULL
++extern void __raise_softirq_irqoff_ksoft(unsigned int nr);
++#else
++static inline void __raise_softirq_irqoff_ksoft(unsigned int nr)
++{
++	__raise_softirq_irqoff(nr);
++}
++#endif
+ 
+ extern void raise_softirq_irqoff(unsigned int nr);
+ extern void raise_softirq(unsigned int nr);
++extern void softirq_check_pending_idle(void);
+ 
+ DECLARE_PER_CPU(struct task_struct *, ksoftirqd);
+ 
+@@ -488,8 +509,9 @@ static inline struct task_struct *this_cpu_ksoftirqd(void)
+      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.
+@@ -514,27 +536,36 @@ struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(1), func, data }
+ 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_atomic();
+ 	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
+@@ -583,12 +614,7 @@ static inline void tasklet_disable(struct tasklet_struct *t)
+ 	smp_mb();
+ }
+ 
+-static inline void tasklet_enable(struct tasklet_struct *t)
+-{
+-	smp_mb__before_atomic();
+-	atomic_dec(&t->count);
+-}
+-
++extern void tasklet_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);
+ extern void tasklet_init(struct tasklet_struct *t,
+@@ -619,6 +645,12 @@ void tasklet_hrtimer_cancel(struct tasklet_hrtimer *ttimer)
+ 	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:
+  *
+diff --git a/include/linux/irq.h b/include/linux/irq.h
+index c4de62348ff2..7432b5e3d79c 100644
+--- a/include/linux/irq.h
++++ b/include/linux/irq.h
+@@ -72,6 +72,7 @@ enum irqchip_irq_state;
+  * IRQ_IS_POLLED		- Always polled by another interrupt. Exclude
+  *				  it from the spurious interrupt detection
+  *				  mechanism and from core side polling.
++ * IRQ_NO_SOFTIRQ_CALL		- No softirq processing in the irq thread context (RT)
+  * IRQ_DISABLE_UNLAZY		- Disable lazy irq disable
+  */
+ enum {
+@@ -99,13 +100,14 @@ enum {
+ 	IRQ_PER_CPU_DEVID	= (1 << 17),
+ 	IRQ_IS_POLLED		= (1 << 18),
+ 	IRQ_DISABLE_UNLAZY	= (1 << 19),
++	IRQ_NO_SOFTIRQ_CALL	= (1 << 20),
+ };
+ 
+ #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_IS_POLLED | IRQ_DISABLE_UNLAZY)
++	 IRQ_IS_POLLED | IRQ_DISABLE_UNLAZY | IRQ_NO_SOFTIRQ_CALL)
+ 
+ #define IRQ_NO_BALANCING_MASK	(IRQ_PER_CPU | IRQ_NO_BALANCING)
+ 
+diff --git a/include/linux/irq_work.h b/include/linux/irq_work.h
+index 47b9ebd4a74f..2543aab05daa 100644
+--- a/include/linux/irq_work.h
++++ b/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;
+@@ -51,4 +52,10 @@ static inline bool irq_work_needs_cpu(void) { return false; }
+ static inline void irq_work_run(void) { }
+ #endif
+ 
++#if defined(CONFIG_IRQ_WORK) && defined(CONFIG_PREEMPT_RT_FULL)
++void irq_work_tick_soft(void);
++#else
++static inline void irq_work_tick_soft(void) { }
++#endif
++
+ #endif /* _LINUX_IRQ_WORK_H */
+diff --git a/include/linux/irqdesc.h b/include/linux/irqdesc.h
+index dcca77c4b9d2..edb6573c9e0e 100644
+--- a/include/linux/irqdesc.h
++++ b/include/linux/irqdesc.h
+@@ -64,6 +64,7 @@ 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
+diff --git a/include/linux/irqflags.h b/include/linux/irqflags.h
+index 5dd1272d1ab2..9b77034f7c5e 100644
+--- a/include/linux/irqflags.h
++++ b/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) || \
+@@ -148,4 +152,23 @@
+ 
+ #define irqs_disabled_flags(flags) raw_irqs_disabled_flags(flags)
+ 
++/*
++ * 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
+diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
+index fd1083c46c61..1485e18b9c3b 100644
+--- a/include/linux/jbd2.h
++++ b/include/linux/jbd2.h
+@@ -347,32 +347,56 @@ static inline struct journal_head *bh2jh(struct buffer_head *bh)
+ 
+ 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
+ }
+ 
+ #define J_ASSERT(assert)	BUG_ON(!(assert))
+diff --git a/include/linux/kdb.h b/include/linux/kdb.h
+index a19bcf9e762e..897495386446 100644
+--- a/include/linux/kdb.h
++++ b/include/linux/kdb.h
+@@ -167,6 +167,7 @@ extern __printf(2, 0) int vkdb_printf(enum kdb_msgsrc src, const char *fmt,
+ 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 */
+@@ -201,6 +202,7 @@ extern int kdb_register_flags(char *, kdb_func_t, char *, char *,
+ 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; }
+diff --git a/include/linux/kernel.h b/include/linux/kernel.h
+index 2f7775e229b0..a7f8e266ab50 100644
+--- a/include/linux/kernel.h
++++ b/include/linux/kernel.h
+@@ -188,6 +188,9 @@ extern int _cond_resched(void);
+  */
+ # define might_sleep() \
+ 	do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
++
++# define might_sleep_no_state_check() \
++	do { ___might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
+ # define sched_annotate_sleep()	(current->task_state_change = 0)
+ #else
+   static inline void ___might_sleep(const char *file, int line,
+@@ -195,6 +198,7 @@ extern int _cond_resched(void);
+   static inline void __might_sleep(const char *file, int line,
+ 				   int preempt_offset) { }
+ # define might_sleep() do { might_resched(); } while (0)
++# define might_sleep_no_state_check() do { might_resched(); } while (0)
+ # define sched_annotate_sleep() do { } while (0)
+ #endif
+ 
+@@ -484,6 +488,7 @@ extern enum system_states {
+ 	SYSTEM_HALT,
+ 	SYSTEM_POWER_OFF,
+ 	SYSTEM_RESTART,
++	SYSTEM_SUSPEND,
+ } system_state;
+ 
+ #define TAINT_PROPRIETARY_MODULE	0
+diff --git a/include/linux/lglock.h b/include/linux/lglock.h
+index c92ebd100d9b..6f035f635d0e 100644
+--- a/include/linux/lglock.h
++++ b/include/linux/lglock.h
+@@ -34,13 +34,30 @@
+ #endif
+ 
+ struct lglock {
++#ifdef CONFIG_PREEMPT_RT_FULL
++	struct rt_mutex __percpu *lock;
++#else
+ 	arch_spinlock_t __percpu *lock;
++#endif
+ #ifdef CONFIG_DEBUG_LOCK_ALLOC
+ 	struct lock_class_key lock_key;
+ 	struct lockdep_map    lock_dep_map;
+ #endif
+ };
+ 
++#ifdef CONFIG_PREEMPT_RT_FULL
++# define DEFINE_LGLOCK(name)						\
++	static DEFINE_PER_CPU(struct rt_mutex, name ## _lock)		\
++	= __RT_MUTEX_INITIALIZER( name ## _lock);			\
++	struct lglock name = { .lock = &name ## _lock }
++
++# define DEFINE_STATIC_LGLOCK(name)					\
++	static DEFINE_PER_CPU(struct rt_mutex, name ## _lock)		\
++	= __RT_MUTEX_INITIALIZER( name ## _lock);			\
++	static struct lglock name = { .lock = &name ## _lock }
++
++#else
++
+ #define DEFINE_LGLOCK(name)						\
+ 	static DEFINE_PER_CPU(arch_spinlock_t, name ## _lock)		\
+ 	= __ARCH_SPIN_LOCK_UNLOCKED;					\
+@@ -50,6 +67,7 @@ struct lglock {
+ 	static DEFINE_PER_CPU(arch_spinlock_t, name ## _lock)		\
+ 	= __ARCH_SPIN_LOCK_UNLOCKED;					\
+ 	static struct lglock name = { .lock = &name ## _lock }
++#endif
+ 
+ void lg_lock_init(struct lglock *lg, char *name);
+ 
+@@ -64,6 +82,12 @@ void lg_double_unlock(struct lglock *lg, int cpu1, int cpu2);
+ void lg_global_lock(struct lglock *lg);
+ void lg_global_unlock(struct lglock *lg);
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
++#define lg_global_trylock_relax(name)	lg_global_lock(name)
++#else
++void lg_global_trylock_relax(struct lglock *lg);
++#endif
++
+ #else
+ /* When !CONFIG_SMP, map lglock to spinlock */
+ #define lglock spinlock
+diff --git a/include/linux/list.h b/include/linux/list.h
+index 5356f4d661a7..3df0783a25e4 100644
+--- a/include/linux/list.h
++++ b/include/linux/list.h
+@@ -679,6 +679,16 @@ static inline bool hlist_fake(struct hlist_node *h)
+ }
+ 
+ /*
++ * Check whether the node is the only node of the head without
++ * accessing head.
++ */
++static inline bool hlist_is_singular_node(struct hlist_node *n,
++					  struct hlist_head *h)
++{
++	return !n->next && n->pprev == &h->first;
++}
++
++/*
+  * Move a list from one list head to another. Fixup the pprev
+  * reference of the first entry if it exists.
+  */
+diff --git a/include/linux/list_bl.h b/include/linux/list_bl.h
+index cb483305e1f5..4e5062316bb6 100644
+--- a/include/linux/list_bl.h
++++ b/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 +33,24 @@
+ 
+ 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)
++
++#ifdef CONFIG_PREEMPT_RT_BASE
++#define INIT_HLIST_BL_HEAD(h)		\
++do {					\
++	(h)->first = NULL;		\
++	raw_spin_lock_init(&(h)->lock);	\
++} while (0)
++#else
++#define INIT_HLIST_BL_HEAD(h) (h)->first = NULL
++#endif
+ 
+ static inline void INIT_HLIST_BL_NODE(struct hlist_bl_node *h)
+ {
+@@ -118,12 +130,26 @@ static inline void hlist_bl_del_init(struct hlist_bl_node *n)
+ 
+ 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)
+diff --git a/include/linux/locallock.h b/include/linux/locallock.h
+new file mode 100644
+index 000000000000..845c77f1a5ca
+--- /dev/null
++++ b/include/linux/locallock.h
+@@ -0,0 +1,278 @@
++#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__no_mg(lock)
++# define spin_trylock_local(lock)		rt_spin_trylock__no_mg(lock)
++# define spin_unlock_local(lock)		rt_spin_unlock__no_mg(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)
++
++#define local_lock_on(lvar, cpu)				\
++	do { __local_lock(&per_cpu(lvar, cpu)); } 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(this_cpu_ptr(&lvar));		\
++		put_local_var(lvar);				\
++	} while (0)
++
++#define local_unlock_on(lvar, cpu)                       \
++	do { __local_unlock(&per_cpu(lvar, cpu)); } 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(this_cpu_ptr(&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 = __this_cpu_read(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(this_cpu_ptr(&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);					\
++		this_cpu_ptr(&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_lock_irq_on(lvar, cpu)		local_irq_disable()
++#define local_unlock_irq(lvar)			local_irq_enable()
++#define local_unlock_irq_on(lvar, cpu)		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
+diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
+index c2d75b4fa86c..8349504e0bbe 100644
+--- a/include/linux/mm_types.h
++++ b/include/linux/mm_types.h
+@@ -11,6 +11,7 @@
+ #include <linux/completion.h>
+ #include <linux/cpumask.h>
+ #include <linux/uprobes.h>
++#include <linux/rcupdate.h>
+ #include <linux/page-flags-layout.h>
+ #include <asm/page.h>
+ #include <asm/mmu.h>
+@@ -502,6 +503,9 @@ struct mm_struct {
+ 	bool tlb_flush_pending;
+ #endif
+ 	struct uprobes_state uprobes_state;
++#ifdef CONFIG_PREEMPT_RT_BASE
++	struct rcu_head delayed_drop;
++#endif
+ #ifdef CONFIG_X86_INTEL_MPX
+ 	/* address of the bounds directory */
+ 	void __user *bd_addr;
+diff --git a/include/linux/mutex.h b/include/linux/mutex.h
+index 2cb7531e7d7a..b3fdfc820216 100644
+--- a/include/linux/mutex.h
++++ b/include/linux/mutex.h
+@@ -19,6 +19,17 @@
+ #include <asm/processor.h>
+ #include <linux/osq_lock.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_killable(struct mutex *lock);
+ 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);
+ 
+ #endif /* __LINUX_MUTEX_H */
+diff --git a/include/linux/mutex_rt.h b/include/linux/mutex_rt.h
+new file mode 100644
+index 000000000000..c38a44b14da5
+--- /dev/null
++++ b/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
+diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
+index 78181a88903b..06863e4f1172 100644
+--- a/include/linux/netdevice.h
++++ b/include/linux/netdevice.h
+@@ -2396,11 +2396,20 @@ void netdev_freemem(struct net_device *dev);
+ void synchronize_net(void);
+ int init_dummy_netdev(struct net_device *dev);
+ 
++#ifdef CONFIG_PREEMPT_RT_FULL
++static inline int dev_recursion_level(void)
++{
++	return current->xmit_recursion;
++}
++
++#else
++
+ DECLARE_PER_CPU(int, xmit_recursion);
+ static inline int dev_recursion_level(void)
+ {
+ 	return this_cpu_read(xmit_recursion);
+ }
++#endif
+ 
+ struct net_device *dev_get_by_index(struct net *net, int ifindex);
+ struct net_device *__dev_get_by_index(struct net *net, int ifindex);
+@@ -2776,6 +2785,7 @@ struct softnet_data {
+ 	unsigned int		dropped;
+ 	struct sk_buff_head	input_pkt_queue;
+ 	struct napi_struct	backlog;
++	struct sk_buff_head	tofree_queue;
+ 
+ };
+ 
+diff --git a/include/linux/netfilter/x_tables.h b/include/linux/netfilter/x_tables.h
+index 4dd9306c9d56..6b13e8fd0aba 100644
+--- a/include/linux/netfilter/x_tables.h
++++ b/include/linux/netfilter/x_tables.h
+@@ -4,6 +4,7 @@
+ 
+ #include <linux/netdevice.h>
+ #include <linux/static_key.h>
++#include <linux/locallock.h>
+ #include <uapi/linux/netfilter/x_tables.h>
+ 
+ /**
+@@ -292,6 +293,8 @@ void xt_free_table_info(struct xt_table_info *info);
+  */
+ DECLARE_PER_CPU(seqcount_t, xt_recseq);
+ 
++DECLARE_LOCAL_IRQ_LOCK(xt_write_lock);
++
+ /* xt_tee_enabled - true if x_tables needs to handle reentrancy
+  *
+  * Enabled if current ip(6)tables ruleset has at least one -j TEE rule.
+@@ -312,6 +315,9 @@ static inline unsigned int xt_write_recseq_begin(void)
+ {
+ 	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().
+@@ -342,6 +348,7 @@ static inline void xt_write_recseq_end(unsigned int addend)
+ 	/* 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);
+ }
+ 
+ /*
+diff --git a/include/linux/notifier.h b/include/linux/notifier.h
+index 4149868de4e6..babe5b9bcb91 100644
+--- a/include/linux/notifier.h
++++ b/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.
+  */
+ 
+ struct notifier_block;
+@@ -90,7 +88,7 @@ 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);
+@@ -103,7 +101,13 @@ extern void srcu_init_notifier_head(struct srcu_notifier_head *nh);
+ 		.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 =			\
+@@ -115,6 +119,18 @@ extern void srcu_init_notifier_head(struct srcu_notifier_head *nh);
+ 	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,
+@@ -184,12 +200,12 @@ static inline int notifier_to_errno(int ret)
+ 
+ /*
+  *	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 */
+diff --git a/include/linux/percpu.h b/include/linux/percpu.h
+index 4bc6dafb703e..c0b6779d8f67 100644
+--- a/include/linux/percpu.h
++++ b/include/linux/percpu.h
+@@ -18,6 +18,35 @@
+ #define PERCPU_MODULE_RESERVE		0
+ #endif
+ 
++#ifdef CONFIG_PREEMPT_RT_FULL
++
++#define get_local_var(var) (*({	\
++	migrate_disable();	\
++	this_cpu_ptr(&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)
++
++#else
++
++#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)
++
++#endif
++
+ /* minimum unit size, also is the maximum supported allocation size */
+ #define PCPU_MIN_UNIT_SIZE		PFN_ALIGN(32 << 10)
+ 
+diff --git a/include/linux/pid.h b/include/linux/pid.h
+index 23705a53abba..2cc64b779f03 100644
+--- a/include/linux/pid.h
++++ b/include/linux/pid.h
+@@ -2,6 +2,7 @@
+ #define _LINUX_PID_H
+ 
+ #include <linux/rcupdate.h>
++#include <linux/atomic.h>
+ 
+ enum pid_type
+ {
+diff --git a/include/linux/preempt.h b/include/linux/preempt.h
+index 75e4e30677f1..1cfb1cb72354 100644
+--- a/include/linux/preempt.h
++++ b/include/linux/preempt.h
+@@ -50,7 +50,11 @@
+ #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
+ 
+ /* We use the MSB mostly because its available */
+ #define PREEMPT_NEED_RESCHED	0x80000000
+@@ -59,9 +63,15 @@
+ #include <asm/preempt.h>
+ 
+ #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?
+@@ -72,7 +82,6 @@
+ #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?
+@@ -91,7 +100,11 @@
+ /*
+  * The preempt_count offset after spin_lock()
+  */
++#if !defined(CONFIG_PREEMPT_RT_FULL)
+ #define PREEMPT_LOCK_OFFSET	PREEMPT_DISABLE_OFFSET
++#else
++#define PREEMPT_LOCK_OFFSET	0
++#endif
+ 
+ /*
+  * The preempt_count offset needed for things like:
+@@ -140,6 +153,20 @@ extern void preempt_count_sub(int val);
+ #define preempt_count_inc() preempt_count_add(1)
+ #define preempt_count_dec() preempt_count_sub(1)
+ 
++#ifdef CONFIG_PREEMPT_LAZY
++#define add_preempt_lazy_count(val)	do { preempt_lazy_count() += (val); } while (0)
++#define sub_preempt_lazy_count(val)	do { preempt_lazy_count() -= (val); } while (0)
++#define inc_preempt_lazy_count()	add_preempt_lazy_count(1)
++#define dec_preempt_lazy_count()	sub_preempt_lazy_count(1)
++#define preempt_lazy_count()		(current_thread_info()->preempt_lazy_count)
++#else
++#define add_preempt_lazy_count(val)	do { } while (0)
++#define sub_preempt_lazy_count(val)	do { } while (0)
++#define inc_preempt_lazy_count()	do { } while (0)
++#define dec_preempt_lazy_count()	do { } while (0)
++#define preempt_lazy_count()		(0)
++#endif
++
+ #ifdef CONFIG_PREEMPT_COUNT
+ 
+ #define preempt_disable() \
+@@ -148,13 +175,25 @@ do { \
+ 	barrier(); \
+ } while (0)
+ 
++#define preempt_lazy_disable() \
++do { \
++	inc_preempt_lazy_count(); \
++	barrier(); \
++} while (0)
++
+ #define sched_preempt_enable_no_resched() \
+ do { \
+ 	barrier(); \
+ 	preempt_count_dec(); \
+ } while (0)
+ 
+-#define preempt_enable_no_resched() sched_preempt_enable_no_resched()
++#ifdef CONFIG_PREEMPT_RT_BASE
++# define preempt_enable_no_resched() sched_preempt_enable_no_resched()
++# define preempt_check_resched_rt() preempt_check_resched()
++#else
++# define preempt_enable_no_resched() preempt_enable()
++# define preempt_check_resched_rt() barrier();
++#endif
+ 
+ #define preemptible()	(preempt_count() == 0 && !irqs_disabled())
+ 
+@@ -179,6 +218,13 @@ do { \
+ 		__preempt_schedule(); \
+ } while (0)
+ 
++#define preempt_lazy_enable() \
++do { \
++	dec_preempt_lazy_count(); \
++	barrier(); \
++	preempt_check_resched(); \
++} while (0)
++
+ #else /* !CONFIG_PREEMPT */
+ #define preempt_enable() \
+ do { \
+@@ -224,6 +270,7 @@ do { \
+ #define preempt_disable_notrace()		barrier()
+ #define preempt_enable_no_resched_notrace()	barrier()
+ #define preempt_enable_notrace()		barrier()
++#define preempt_check_resched_rt()		barrier()
+ #define preemptible()				0
+ 
+ #endif /* CONFIG_PREEMPT_COUNT */
+@@ -244,10 +291,31 @@ do { \
+ } while (0)
+ #define preempt_fold_need_resched() \
+ do { \
+-	if (tif_need_resched()) \
++	if (tif_need_resched_now()) \
+ 		set_preempt_need_resched(); \
+ } while (0)
+ 
++#ifdef CONFIG_PREEMPT_RT_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;
+diff --git a/include/linux/printk.h b/include/linux/printk.h
+index 9ccbdf2c1453..428d6a7fa4e8 100644
+--- a/include/linux/printk.h
++++ b/include/linux/printk.h
+@@ -117,9 +117,11 @@ do {						\
+ #ifdef CONFIG_EARLY_PRINTK
+ extern asmlinkage __printf(1, 2)
+ void early_printk(const char *fmt, ...);
++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
+ 
+ typedef __printf(1, 0) int (*printk_func_t)(const char *fmt, va_list args);
+diff --git a/include/linux/radix-tree.h b/include/linux/radix-tree.h
+index 51a97ac8bfbf..0608483c91fc 100644
+--- a/include/linux/radix-tree.h
++++ b/include/linux/radix-tree.h
+@@ -294,8 +294,13 @@ radix_tree_gang_lookup(struct radix_tree_root *root, void **results,
+ unsigned int radix_tree_gang_lookup_slot(struct radix_tree_root *root,
+ 			void ***results, unsigned long *indices,
+ 			unsigned long first_index, unsigned int max_items);
++#ifndef CONFIG_PREEMPT_RT_FULL
+ int radix_tree_preload(gfp_t gfp_mask);
+ int radix_tree_maybe_preload(gfp_t gfp_mask);
++#else
++static inline int radix_tree_preload(gfp_t gm) { return 0; }
++static inline int radix_tree_maybe_preload(gfp_t gfp_mask) { return 0; }
++#endif
+ void radix_tree_init(void);
+ void *radix_tree_tag_set(struct radix_tree_root *root,
+ 			unsigned long index, unsigned int tag);
+@@ -320,7 +325,7 @@ unsigned long radix_tree_locate_item(struct radix_tree_root *root, void *item);
+ 
+ static inline void radix_tree_preload_end(void)
+ {
+-	preempt_enable();
++	preempt_enable_nort();
+ }
+ 
+ /**
+diff --git a/include/linux/random.h b/include/linux/random.h
+index 9c29122037f9..e7f2f8604918 100644
+--- a/include/linux/random.h
++++ b/include/linux/random.h
+@@ -20,7 +20,7 @@ struct random_ready_callback {
+ 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 int add_random_ready_callback(struct random_ready_callback *rdy);
+diff --git a/include/linux/rbtree.h b/include/linux/rbtree.h
+index b6900099ea81..fdc2e95173e0 100644
+--- a/include/linux/rbtree.h
++++ b/include/linux/rbtree.h
+@@ -31,7 +31,6 @@
+ 
+ #include <linux/kernel.h>
+ #include <linux/stddef.h>
+-#include <linux/rcupdate.h>
+ 
+ struct rb_node {
+ 	unsigned long  __rb_parent_color;
+@@ -86,14 +85,8 @@ static inline void rb_link_node(struct rb_node *node, struct rb_node *parent,
+ 	*rb_link = node;
+ }
+ 
+-static inline void rb_link_node_rcu(struct rb_node *node, struct rb_node *parent,
+-				    struct rb_node **rb_link)
+-{
+-	node->__rb_parent_color = (unsigned long)parent;
+-	node->rb_left = node->rb_right = NULL;
+-
+-	rcu_assign_pointer(*rb_link, node);
+-}
++void rb_link_node_rcu(struct rb_node *node, struct rb_node *parent,
++		      struct rb_node **rb_link);
+ 
+ #define rb_entry_safe(ptr, type, member) \
+ 	({ typeof(ptr) ____ptr = (ptr); \
+diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h
+index 2657aff2725b..ea90179fee34 100644
+--- a/include/linux/rcupdate.h
++++ b/include/linux/rcupdate.h
+@@ -177,6 +177,9 @@ void call_rcu(struct rcu_head *head,
+ 
+ #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.
+@@ -200,6 +203,7 @@ void call_rcu(struct rcu_head *head,
+  */
+ void call_rcu_bh(struct rcu_head *head,
+ 		 rcu_callback_t func);
++#endif
+ 
+ /**
+  * call_rcu_sched() - Queue an RCU for invocation after sched grace period.
+@@ -300,6 +304,11 @@ 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 */
+ 
+@@ -325,6 +334,8 @@ 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 */
+@@ -498,7 +509,14 @@ extern struct lockdep_map rcu_callback_map;
+ int debug_lockdep_rcu_enabled(void);
+ 
+ int rcu_read_lock_held(void);
++#ifdef CONFIG_PREEMPT_RT_FULL
++static inline int rcu_read_lock_bh_held(void)
++{
++	return rcu_read_lock_held();
++}
++#else
+ int rcu_read_lock_bh_held(void);
++#endif
+ 
+ /**
+  * rcu_read_lock_sched_held() - might we be in RCU-sched read-side critical section?
+@@ -946,10 +964,14 @@ 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_WARN(!rcu_is_watching(),
+ 			 "rcu_read_lock_bh() used illegally while idle");
++#endif
+ }
+ 
+ /*
+@@ -959,10 +981,14 @@ 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_WARN(!rcu_is_watching(),
+ 			 "rcu_read_unlock_bh() used illegally while idle");
+ 	rcu_lock_release(&rcu_bh_lock_map);
+ 	__release(RCU_BH);
++#endif
+ 	local_bh_enable();
+ }
+ 
+diff --git a/include/linux/rcutree.h b/include/linux/rcutree.h
+index ad1eda9fa4da..732192c5da11 100644
+--- a/include/linux/rcutree.h
++++ b/include/linux/rcutree.h
+@@ -44,7 +44,11 @@ static inline void rcu_virt_note_context_switch(int cpu)
+ 	rcu_note_context_switch();
+ }
+ 
++#ifdef CONFIG_PREEMPT_RT_FULL
++# define synchronize_rcu_bh	synchronize_rcu
++#else
+ void synchronize_rcu_bh(void);
++#endif
+ void synchronize_sched_expedited(void);
+ void synchronize_rcu_expedited(void);
+ 
+@@ -72,7 +76,11 @@ static inline void synchronize_rcu_bh_expedited(void)
+ }
+ 
+ void rcu_barrier(void);
++#ifdef CONFIG_PREEMPT_RT_FULL
++# define rcu_barrier_bh                rcu_barrier
++#else
+ void rcu_barrier_bh(void);
++#endif
+ void rcu_barrier_sched(void);
+ unsigned long get_state_synchronize_rcu(void);
+ void cond_synchronize_rcu(unsigned long oldstate);
+@@ -85,12 +93,10 @@ unsigned long rcu_batches_started(void);
+ unsigned long rcu_batches_started_bh(void);
+ unsigned long rcu_batches_started_sched(void);
+ unsigned long rcu_batches_completed(void);
+-unsigned long rcu_batches_completed_bh(void);
+ unsigned long rcu_batches_completed_sched(void);
+ void show_rcu_gp_kthreads(void);
+ 
+ void rcu_force_quiescent_state(void);
+-void rcu_bh_force_quiescent_state(void);
+ void rcu_sched_force_quiescent_state(void);
+ 
+ void rcu_idle_enter(void);
+@@ -107,6 +113,14 @@ extern int rcu_scheduler_active __read_mostly;
+ 
+ bool rcu_is_watching(void);
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
++void rcu_bh_force_quiescent_state(void);
++unsigned 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
++
+ void rcu_all_qs(void);
+ 
+ #endif /* __LINUX_RCUTREE_H */
+diff --git a/include/linux/rtmutex.h b/include/linux/rtmutex.h
+index 1abba5ce2a2f..30211c627511 100644
+--- a/include/linux/rtmutex.h
++++ b/include/linux/rtmutex.h
+@@ -13,11 +13,15 @@
+ #define __LINUX_RT_MUTEX_H
+ 
+ #include <linux/linkage.h>
++#include <linux/spinlock_types_raw.h>
+ #include <linux/rbtree.h>
+-#include <linux/spinlock_types.h>
+ 
+ extern int max_lock_depth; /* for sysctl */
+ 
++#ifdef CONFIG_DEBUG_MUTEXES
++#include <linux/debug_locks.h>
++#endif
++
+ /**
+  * The rt_mutex structure
+  *
+@@ -31,8 +35,8 @@ struct rt_mutex {
+ 	struct rb_root          waiters;
+ 	struct rb_node          *waiters_leftmost;
+ 	struct task_struct	*owner;
+-#ifdef CONFIG_DEBUG_RT_MUTEXES
+ 	int			save_state;
++#ifdef CONFIG_DEBUG_RT_MUTEXES
+ 	const char 		*name, *file;
+ 	int			line;
+ 	void			*magic;
+@@ -55,22 +59,33 @@ struct hrtimer_sleeper;
+ # define rt_mutex_debug_check_no_locks_held(task)	do { } while (0)
+ #endif
+ 
++# define rt_mutex_init(mutex)					\
++	do {							\
++		raw_spin_lock_init(&(mutex)->wait_lock);	\
++		__rt_mutex_init(mutex, #mutex);			\
++	} while (0)
++
+ #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__)
+  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_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) \
+ 	, .waiters = RB_ROOT \
+ 	, .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)
+@@ -91,6 +106,7 @@ extern void rt_mutex_destroy(struct rt_mutex *lock);
+ 
+ extern void rt_mutex_lock(struct rt_mutex *lock);
+ extern int rt_mutex_lock_interruptible(struct rt_mutex *lock);
++extern int rt_mutex_lock_killable(struct rt_mutex *lock);
+ extern int rt_mutex_timed_lock(struct rt_mutex *lock,
+ 			       struct hrtimer_sleeper *timeout);
+ 
+diff --git a/include/linux/rwlock_rt.h b/include/linux/rwlock_rt.h
+new file mode 100644
+index 000000000000..49ed2d45d3be
+--- /dev/null
++++ b/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
+diff --git a/include/linux/rwlock_types.h b/include/linux/rwlock_types.h
+index cc0072e93e36..5317cd957292 100644
+--- a/include/linux/rwlock_types.h
++++ b/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
+diff --git a/include/linux/rwlock_types_rt.h b/include/linux/rwlock_types_rt.h
+new file mode 100644
+index 000000000000..51b28d775fe1
+--- /dev/null
++++ b/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 = __RW_LOCK_UNLOCKED(name)
++
++#endif
+diff --git a/include/linux/rwsem.h b/include/linux/rwsem.h
+index 8f498cdde280..2b2148431f14 100644
+--- a/include/linux/rwsem.h
++++ b/include/linux/rwsem.h
+@@ -18,6 +18,10 @@
+ #include <linux/osq_lock.h>
+ #endif
+ 
++#ifdef CONFIG_PREEMPT_RT_FULL
++#include <linux/rwsem_rt.h>
++#else /* PREEMPT_RT_FULL */
++
+ struct rw_semaphore;
+ 
+ #ifdef CONFIG_RWSEM_GENERIC_SPINLOCK
+@@ -177,4 +181,6 @@ extern void up_read_non_owner(struct rw_semaphore *sem);
+ # define up_read_non_owner(sem)			up_read(sem)
+ #endif
+ 
++#endif /* !PREEMPT_RT_FULL */
++
+ #endif /* _LINUX_RWSEM_H */
+diff --git a/include/linux/rwsem_rt.h b/include/linux/rwsem_rt.h
+new file mode 100644
+index 000000000000..f97860b2e2a4
+--- /dev/null
++++ b/include/linux/rwsem_rt.h
+@@ -0,0 +1,152 @@
++#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 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 int  rt_down_read_trylock(struct rw_semaphore *rwsem);
++extern void __rt_up_read(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 int rwsem_is_contended(struct rw_semaphore *sem)
++{
++	/* rt_mutex_has_waiters() */
++	return !RB_EMPTY_ROOT(&sem->lock.waiters);
++}
++
++static inline void __down_read(struct rw_semaphore *sem)
++{
++	rt__down_read(sem);
++}
++
++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 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_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
+diff --git a/include/linux/sched.h b/include/linux/sched.h
+index 52c4847b05e2..c242cbd84485 100644
+--- a/include/linux/sched.h
++++ b/include/linux/sched.h
+@@ -26,6 +26,7 @@ struct sched_param {
+ #include <linux/nodemask.h>
+ #include <linux/mm_types.h>
+ #include <linux/preempt.h>
++#include <asm/kmap_types.h>
+ 
+ #include <asm/page.h>
+ #include <asm/ptrace.h>
+@@ -241,10 +242,7 @@ extern char ___assert_task_state[1 - 2*!!(
+ 				 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
+ 				 __TASK_TRACED | EXIT_ZOMBIE | EXIT_DEAD)
+ 
+-#define task_is_traced(task)	((task->state & __TASK_TRACED) != 0)
+ #define task_is_stopped(task)	((task->state & __TASK_STOPPED) != 0)
+-#define task_is_stopped_or_traced(task)	\
+-			((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
+ #define task_contributes_to_load(task)	\
+ 				((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
+ 				 (task->flags & PF_FROZEN) == 0 && \
+@@ -310,6 +308,11 @@ extern char ___assert_task_state[1 - 2*!!(
+ 
+ #endif
+ 
++#define __set_current_state_no_track(state_value)	\
++	do { current->state = (state_value); } while (0)
++#define set_current_state_no_track(state_value)		\
++	set_mb(current->state, (state_value))
++
+ /* Task command name length */
+ #define TASK_COMM_LEN 16
+ 
+@@ -981,8 +984,18 @@ struct wake_q_head {
+ 	struct wake_q_head name = { WAKE_Q_TAIL, &name.first }
+ 
+ extern void wake_q_add(struct wake_q_head *head,
+-		       struct task_struct *task);
+-extern void wake_up_q(struct wake_q_head *head);
++			      struct task_struct *task);
++extern void __wake_up_q(struct wake_q_head *head, bool sleeper);
++
++static inline void wake_up_q(struct wake_q_head *head)
++{
++	__wake_up_q(head, false);
++}
++
++static inline void wake_up_q_sleeper(struct wake_q_head *head)
++{
++	__wake_up_q(head, true);
++}
+ 
+ /*
+  * sched-domains (multiprocessor balancing) declarations:
+@@ -1393,6 +1406,7 @@ struct tlbflush_unmap_batch {
+ 
+ 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 */
+@@ -1429,6 +1443,12 @@ 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;
+ 
+@@ -1559,6 +1579,9 @@ 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
+@@ -1589,10 +1612,15 @@ 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;
+@@ -1820,6 +1848,12 @@ struct task_struct {
+ 	/* bitmask and counter of trace recursion */
+ 	unsigned long trace_recursion;
+ #endif /* CONFIG_TRACING */
++#ifdef CONFIG_WAKEUP_LATENCY_HIST
++	u64 preempt_timestamp_hist;
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++	long timer_offset;
++#endif
++#endif
+ #ifdef CONFIG_KCOV
+ 	/* Coverage collection mode enabled for this task (0 if disabled). */
+ 	enum kcov_mode kcov_mode;
+@@ -1845,9 +1879,23 @@ 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
+ #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
+ 	unsigned long	task_state_change;
+ #endif
++#ifdef CONFIG_PREEMPT_RT_FULL
++	int xmit_recursion;
++#endif
+ 	int pagefault_disabled;
+ #ifdef CONFIG_MMU
+ 	struct task_struct *oom_reaper_list;
+@@ -1868,9 +1916,6 @@ extern int arch_task_struct_size __read_mostly;
+ # define arch_task_struct_size (sizeof(struct task_struct))
+ #endif
+ 
+-/* Future-safe accessor for struct task_struct's cpus_allowed. */
+-#define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
+-
+ #define TNF_MIGRATED	0x01
+ #define TNF_NO_GROUP	0x02
+ #define TNF_SHARED	0x04
+@@ -2060,6 +2105,15 @@ 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)
+@@ -2067,6 +2121,7 @@ static inline void put_task_struct(struct task_struct *t)
+ 	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,
+@@ -2105,6 +2160,7 @@ extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut,
+ /*
+  * 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 */
+@@ -2269,6 +2325,10 @@ extern void do_set_cpus_allowed(struct task_struct *p,
+ 
+ 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)
+@@ -2281,6 +2341,9 @@ static inline int set_cpus_allowed_ptr(struct task_struct *p,
+ 		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
+@@ -2487,6 +2550,7 @@ extern void xtime_update(unsigned long ticks);
+ 
+ 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);
+@@ -2610,12 +2674,24 @@ 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 */
+@@ -2933,6 +3009,43 @@ static inline int test_tsk_need_resched(struct task_struct *tsk)
+ 	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
+ }
+ 
++#ifdef CONFIG_PREEMPT_LAZY
++static inline void set_tsk_need_resched_lazy(struct task_struct *tsk)
++{
++	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED_LAZY);
++}
++
++static inline void clear_tsk_need_resched_lazy(struct task_struct *tsk)
++{
++	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED_LAZY);
++}
++
++static inline int test_tsk_need_resched_lazy(struct task_struct *tsk)
++{
++	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED_LAZY));
++}
++
++static inline int need_resched_lazy(void)
++{
++	return test_thread_flag(TIF_NEED_RESCHED_LAZY);
++}
++
++static inline int need_resched_now(void)
++{
++	return test_thread_flag(TIF_NEED_RESCHED);
++}
++
++#else
++static inline void clear_tsk_need_resched_lazy(struct task_struct *tsk) { }
++static inline int need_resched_lazy(void) { return 0; }
++
++static inline int need_resched_now(void)
++{
++	return test_thread_flag(TIF_NEED_RESCHED);
++}
++
++#endif
++
+ static inline int restart_syscall(void)
+ {
+ 	set_tsk_thread_flag(current, TIF_SIGPENDING);
+@@ -2964,6 +3077,51 @@ static inline int signal_pending_state(long state, struct task_struct *p)
+ 	return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
+ }
+ 
++static inline bool __task_is_stopped_or_traced(struct task_struct *task)
++{
++	if (task->state & (__TASK_STOPPED | __TASK_TRACED))
++		return true;
++#ifdef CONFIG_PREEMPT_RT_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;
++}
++
+ /*
+  * cond_resched() and cond_resched_lock(): latency reduction via
+  * explicit rescheduling in places that are safe. The return
+@@ -2985,12 +3143,16 @@ extern int __cond_resched_lock(spinlock_t *lock);
+ 	__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)
+ {
+@@ -3152,6 +3314,31 @@ static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
+ 
+ #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)
++{
++	if (__migrate_disabled(p))
++		return cpumask_of(task_cpu(p));
++
++	return &p->cpus_allowed;
++}
++
++static inline int tsk_nr_cpus_allowed(struct task_struct *p)
++{
++	if (__migrate_disabled(p))
++		return 1;
++	return p->nr_cpus_allowed;
++}
++
+ extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
+ extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
+ 
+diff --git a/include/linux/seqlock.h b/include/linux/seqlock.h
+index e0582106ef4f..b14f4d2368aa 100644
+--- a/include/linux/seqlock.h
++++ b/include/linux/seqlock.h
+@@ -220,20 +220,30 @@ static inline int read_seqcount_retry(const seqcount_t *s, unsigned start)
+ 	return __read_seqcount_retry(s, start);
+ }
+ 
+-
+-
+-static inline void raw_write_seqcount_begin(seqcount_t *s)
++static inline void __raw_write_seqcount_begin(seqcount_t *s)
+ {
+ 	s->sequence++;
+ 	smp_wmb();
+ }
+ 
+-static inline void raw_write_seqcount_end(seqcount_t *s)
++static inline void raw_write_seqcount_begin(seqcount_t *s)
++{
++	preempt_disable_rt();
++	__raw_write_seqcount_begin(s);
++}
++
++static inline void __raw_write_seqcount_end(seqcount_t *s)
+ {
+ 	smp_wmb();
+ 	s->sequence++;
+ }
+ 
++static inline void raw_write_seqcount_end(seqcount_t *s)
++{
++	__raw_write_seqcount_end(s);
++	preempt_enable_rt();
++}
++
+ /**
+  * raw_write_seqcount_barrier - do a seq write barrier
+  * @s: pointer to seqcount_t
+@@ -425,10 +435,32 @@ 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)
+ {
+@@ -443,36 +475,36 @@ static inline unsigned read_seqretry(const seqlock_t *sl, unsigned start)
+ static inline void write_seqlock(seqlock_t *sl)
+ {
+ 	spin_lock(&sl->lock);
+-	write_seqcount_begin(&sl->seqcount);
++	__raw_write_seqcount_begin(&sl->seqcount);
+ }
+ 
+ static inline void write_sequnlock(seqlock_t *sl)
+ {
+-	write_seqcount_end(&sl->seqcount);
++	__raw_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);
++	__raw_write_seqcount_begin(&sl->seqcount);
+ }
+ 
+ static inline void write_sequnlock_bh(seqlock_t *sl)
+ {
+-	write_seqcount_end(&sl->seqcount);
++	__raw_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);
++	__raw_write_seqcount_begin(&sl->seqcount);
+ }
+ 
+ static inline void write_sequnlock_irq(seqlock_t *sl)
+ {
+-	write_seqcount_end(&sl->seqcount);
++	__raw_write_seqcount_end(&sl->seqcount);
+ 	spin_unlock_irq(&sl->lock);
+ }
+ 
+@@ -481,7 +513,7 @@ static inline unsigned long __write_seqlock_irqsave(seqlock_t *sl)
+ 	unsigned long flags;
+ 
+ 	spin_lock_irqsave(&sl->lock, flags);
+-	write_seqcount_begin(&sl->seqcount);
++	__raw_write_seqcount_begin(&sl->seqcount);
+ 	return flags;
+ }
+ 
+@@ -491,7 +523,7 @@ static inline unsigned long __write_seqlock_irqsave(seqlock_t *sl)
+ static inline void
+ write_sequnlock_irqrestore(seqlock_t *sl, unsigned long flags)
+ {
+-	write_seqcount_end(&sl->seqcount);
++	__raw_write_seqcount_end(&sl->seqcount);
+ 	spin_unlock_irqrestore(&sl->lock, flags);
+ }
+ 
+diff --git a/include/linux/signal.h b/include/linux/signal.h
+index d80259afb9e5..ddd1e6866a54 100644
+--- a/include/linux/signal.h
++++ b/include/linux/signal.h
+@@ -233,6 +233,7 @@ static inline void init_sigpending(struct sigpending *sig)
+ }
+ 
+ extern void flush_sigqueue(struct sigpending *queue);
++extern void flush_task_sigqueue(struct task_struct *tsk);
+ 
+ /* Test if 'sig' is valid signal. Use this instead of testing _NSIG directly */
+ static inline int valid_signal(unsigned long sig)
+diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
+index 794b924e9669..db2af7c88a6a 100644
+--- a/include/linux/skbuff.h
++++ b/include/linux/skbuff.h
+@@ -283,6 +283,7 @@ struct sk_buff_head {
+ 
+ 	__u32		qlen;
+ 	spinlock_t	lock;
++	raw_spinlock_t	raw_lock;
+ };
+ 
+ struct sk_buff;
+@@ -1538,6 +1539,12 @@ static inline void skb_queue_head_init(struct sk_buff_head *list)
+ 	__skb_queue_head_init(list);
+ }
+ 
++static inline void skb_queue_head_init_raw(struct sk_buff_head *list)
++{
++	raw_spin_lock_init(&list->raw_lock);
++	__skb_queue_head_init(list);
++}
++
+ static inline void skb_queue_head_init_class(struct sk_buff_head *list,
+ 		struct lock_class_key *class)
+ {
+diff --git a/include/linux/smp.h b/include/linux/smp.h
+index c4414074bd88..e6ab36aeaaab 100644
+--- a/include/linux/smp.h
++++ b/include/linux/smp.h
+@@ -185,6 +185,9 @@ static inline void smp_init(void) { }
+ #define get_cpu()		({ preempt_disable(); smp_processor_id(); })
+ #define put_cpu()		preempt_enable()
+ 
++#define get_cpu_light()		({ migrate_disable(); smp_processor_id(); })
++#define put_cpu_light()		migrate_enable()
++
+ /*
+  * Callback to arch code if there's nosmp or maxcpus=0 on the
+  * boot command line:
+diff --git a/include/linux/spinlock.h b/include/linux/spinlock.h
+index 47dd0cebd204..b241cc044bd3 100644
+--- a/include/linux/spinlock.h
++++ b/include/linux/spinlock.h
+@@ -271,7 +271,11 @@ static inline void do_raw_spin_unlock(raw_spinlock_t *lock) __releases(lock)
+ #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:
+@@ -282,6 +286,10 @@ static inline void do_raw_spin_unlock(raw_spinlock_t *lock) __releases(lock)
+ # 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
+  */
+@@ -416,4 +424,6 @@ extern int _atomic_dec_and_lock(atomic_t *atomic, spinlock_t *lock);
+ #define atomic_dec_and_lock(atomic, lock) \
+ 		__cond_lock(lock, _atomic_dec_and_lock(atomic, lock))
+ 
++#endif /* !PREEMPT_RT_FULL */
++
+ #endif /* __LINUX_SPINLOCK_H */
+diff --git a/include/linux/spinlock_api_smp.h b/include/linux/spinlock_api_smp.h
+index 5344268e6e62..043263f30e81 100644
+--- a/include/linux/spinlock_api_smp.h
++++ b/include/linux/spinlock_api_smp.h
+@@ -189,6 +189,8 @@ static inline int __raw_spin_trylock_bh(raw_spinlock_t *lock)
+ 	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 */
+diff --git a/include/linux/spinlock_rt.h b/include/linux/spinlock_rt.h
+new file mode 100644
+index 000000000000..3b2825537531
+--- /dev/null
++++ b/include/linux/spinlock_rt.h
+@@ -0,0 +1,163 @@
++#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)
++
++void __lockfunc rt_spin_lock__no_mg(spinlock_t *lock);
++void __lockfunc rt_spin_unlock__no_mg(spinlock_t *lock);
++int __lockfunc rt_spin_trylock__no_mg(spinlock_t *lock);
++
++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_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__no_mg(struct rt_mutex *lock);
++extern void __lockfunc __rt_spin_lock(struct rt_mutex *lock);
++extern void __lockfunc __rt_spin_unlock(struct rt_mutex *lock);
++extern int __lockfunc __rt_spin_trylock(struct rt_mutex *lock);
++
++#define spin_lock(lock)			rt_spin_lock(lock)
++
++#define spin_lock_bh(lock)			\
++	do {					\
++		local_bh_disable();		\
++		rt_spin_lock(lock);		\
++	} while (0)
++
++#define spin_lock_irq(lock)		spin_lock(lock)
++
++#define spin_do_trylock(lock)		__cond_lock(lock, rt_spin_trylock(lock))
++
++#define spin_trylock(lock)			\
++({						\
++	int __locked;				\
++	__locked = spin_do_trylock(lock);	\
++	__locked;				\
++})
++
++#ifdef CONFIG_LOCKDEP
++# define spin_lock_nested(lock, subclass)		\
++	do {						\
++		rt_spin_lock_nested(lock, subclass);	\
++	} while (0)
++
++#define spin_lock_bh_nested(lock, subclass)		\
++	do {						\
++		local_bh_disable();			\
++		rt_spin_lock_nested(lock, subclass);	\
++	} while (0)
++
++# define spin_lock_irqsave_nested(lock, flags, subclass) \
++	do {						 \
++		typecheck(unsigned long, flags);	 \
++		flags = 0;				 \
++		rt_spin_lock_nested(lock, subclass);	 \
++	} while (0)
++#else
++# define spin_lock_nested(lock, subclass)	spin_lock(lock)
++# define spin_lock_bh_nested(lock, subclass)	spin_lock_bh(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)			rt_spin_unlock(lock)
++
++#define spin_unlock_bh(lock)				\
++	do {						\
++		rt_spin_unlock(lock);			\
++		local_bh_enable();			\
++	} while (0)
++
++#define spin_unlock_irq(lock)		spin_unlock(lock)
++
++#define spin_unlock_irqrestore(lock, flags)		\
++	do {						\
++		typecheck(unsigned long, flags);	\
++		(void) flags;				\
++		spin_unlock(lock);			\
++	} while (0)
++
++#define spin_trylock_bh(lock)	__cond_lock(lock, rt_spin_trylock_bh(lock))
++#define spin_trylock_irq(lock)	spin_trylock(lock)
++
++#define spin_trylock_irqsave(lock, flags)	\
++	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
+diff --git a/include/linux/spinlock_types.h b/include/linux/spinlock_types.h
+index 73548eb13a5d..10bac715ea96 100644
+--- a/include/linux/spinlock_types.h
++++ b/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>
++#include <linux/spinlock_types_raw.h>
++
++#ifndef CONFIG_PREEMPT_RT_FULL
++# include <linux/spinlock_types_nort.h>
++# include <linux/rwlock_types.h>
+ #else
+-# include <linux/spinlock_types_up.h>
++# include <linux/rtmutex.h>
++# include <linux/spinlock_types_rt.h>
++# include <linux/rwlock_types_rt.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)
+-
+-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 */
+diff --git a/include/linux/spinlock_types_nort.h b/include/linux/spinlock_types_nort.h
+new file mode 100644
+index 000000000000..f1dac1fb1d6a
+--- /dev/null
++++ b/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
+diff --git a/include/linux/spinlock_types_raw.h b/include/linux/spinlock_types_raw.h
+new file mode 100644
+index 000000000000..edffc4d53fc9
+--- /dev/null
++++ b/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
+diff --git a/include/linux/spinlock_types_rt.h b/include/linux/spinlock_types_rt.h
+new file mode 100644
+index 000000000000..3e3d8c5f7a9a
+--- /dev/null
++++ b/include/linux/spinlock_types_rt.h
+@@ -0,0 +1,48 @@
++#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)
++
++#endif
+diff --git a/include/linux/srcu.h b/include/linux/srcu.h
+index dc8eb63c6568..e793d3a257da 100644
+--- a/include/linux/srcu.h
++++ b/include/linux/srcu.h
+@@ -84,10 +84,10 @@ int init_srcu_struct(struct srcu_struct *sp);
+ 
+ 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),	\
+@@ -119,7 +119,7 @@ void process_srcu(struct work_struct *work);
+  */
+ #define __DEFINE_SRCU(name, is_static)					\
+ 	static DEFINE_PER_CPU(struct srcu_struct_array, name##_srcu_array);\
+-	is_static struct srcu_struct name = __SRCU_STRUCT_INIT(name)
++	is_static struct srcu_struct name = __SRCU_STRUCT_INIT(name, name##_srcu_array)
+ #define DEFINE_SRCU(name)		__DEFINE_SRCU(name, /* not static */)
+ #define DEFINE_STATIC_SRCU(name)	__DEFINE_SRCU(name, static)
+ 
+diff --git a/include/linux/suspend.h b/include/linux/suspend.h
+index 8b6ec7ef0854..9b77d4cc929f 100644
+--- a/include/linux/suspend.h
++++ b/include/linux/suspend.h
+@@ -194,6 +194,12 @@ struct platform_freeze_ops {
+ 	void (*end)(void);
+ };
+ 
++#if defined(CONFIG_SUSPEND) || defined(CONFIG_HIBERNATION)
++extern bool pm_in_action;
++#else
++# define pm_in_action false
++#endif
++
+ #ifdef CONFIG_SUSPEND
+ /**
+  * suspend_set_ops - set platform dependent suspend operations
+diff --git a/include/linux/swait.h b/include/linux/swait.h
+index c1f9c62a8a50..83f004a72320 100644
+--- a/include/linux/swait.h
++++ b/include/linux/swait.h
+@@ -87,6 +87,7 @@ static inline int swait_active(struct swait_queue_head *q)
+ extern void swake_up(struct swait_queue_head *q);
+ extern void swake_up_all(struct swait_queue_head *q);
+ extern void swake_up_locked(struct swait_queue_head *q);
++extern void swake_up_all_locked(struct swait_queue_head *q);
+ 
+ extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait);
+ extern void prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait, int state);
+diff --git a/include/linux/swap.h b/include/linux/swap.h
+index ad220359f1b0..2b7721949dd5 100644
+--- a/include/linux/swap.h
++++ b/include/linux/swap.h
+@@ -11,6 +11,7 @@
+ #include <linux/fs.h>
+ #include <linux/atomic.h>
+ #include <linux/page-flags.h>
++#include <linux/locallock.h>
+ #include <asm/page.h>
+ 
+ struct notifier_block;
+@@ -252,7 +253,8 @@ struct swap_info_struct {
+ void *workingset_eviction(struct address_space *mapping, struct page *page);
+ bool workingset_refault(void *shadow);
+ void workingset_activation(struct page *page);
+-extern struct list_lru workingset_shadow_nodes;
++extern struct list_lru __workingset_shadow_nodes;
++DECLARE_LOCAL_IRQ_LOCK(workingset_shadow_lock);
+ 
+ static inline unsigned int workingset_node_pages(struct radix_tree_node *node)
+ {
+@@ -295,6 +297,7 @@ extern unsigned long nr_free_pagecache_pages(void);
+ 
+ 
+ /* linux/mm/swap.c */
++DECLARE_LOCAL_IRQ_LOCK(swapvec_lock);
+ extern void lru_cache_add(struct page *);
+ extern void lru_cache_add_anon(struct page *page);
+ extern void lru_cache_add_file(struct page *page);
+diff --git a/include/linux/swork.h b/include/linux/swork.h
+new file mode 100644
+index 000000000000..f175fa9a6016
+--- /dev/null
++++ b/include/linux/swork.h
+@@ -0,0 +1,24 @@
++#ifndef _LINUX_SWORK_H
++#define _LINUX_SWORK_H
++
++#include <linux/list.h>
++
++struct swork_event {
++	struct list_head item;
++	unsigned long flags;
++	void (*func)(struct swork_event *);
++};
++
++static inline void INIT_SWORK(struct swork_event *event,
++			      void (*func)(struct swork_event *))
++{
++	event->flags = 0;
++	event->func = func;
++}
++
++bool swork_queue(struct swork_event *sev);
++
++int swork_get(void);
++void swork_put(void);
++
++#endif /* _LINUX_SWORK_H */
+diff --git a/include/linux/thread_info.h b/include/linux/thread_info.h
+index b4c2a485b28a..5580c2c8410d 100644
+--- a/include/linux/thread_info.h
++++ b/include/linux/thread_info.h
+@@ -103,7 +103,17 @@ static inline int test_ti_thread_flag(struct thread_info *ti, int flag)
+ #define test_thread_flag(flag) \
+ 	test_ti_thread_flag(current_thread_info(), flag)
+ 
+-#define tif_need_resched() test_thread_flag(TIF_NEED_RESCHED)
++#ifdef CONFIG_PREEMPT_LAZY
++#define tif_need_resched()	(test_thread_flag(TIF_NEED_RESCHED) || \
++				 test_thread_flag(TIF_NEED_RESCHED_LAZY))
++#define tif_need_resched_now()	(test_thread_flag(TIF_NEED_RESCHED))
++#define tif_need_resched_lazy()	test_thread_flag(TIF_NEED_RESCHED_LAZY))
++
++#else
++#define tif_need_resched()	test_thread_flag(TIF_NEED_RESCHED)
++#define tif_need_resched_now()	test_thread_flag(TIF_NEED_RESCHED)
++#define tif_need_resched_lazy()	0
++#endif
+ 
+ #if defined TIF_RESTORE_SIGMASK && !defined HAVE_SET_RESTORE_SIGMASK
+ /*
+diff --git a/include/linux/timer.h b/include/linux/timer.h
+index 61aa61dc410c..a915acbd0072 100644
+--- a/include/linux/timer.h
++++ b/include/linux/timer.h
+@@ -19,7 +19,6 @@ struct timer_list {
+ 	void			(*function)(unsigned long);
+ 	unsigned long		data;
+ 	u32			flags;
+-	int			slack;
+ 
+ #ifdef CONFIG_TIMER_STATS
+ 	int			start_pid;
+@@ -58,11 +57,14 @@ struct timer_list {
+  * workqueue locking issues. It's not meant for executing random crap
+  * with interrupts disabled. Abuse is monitored!
+  */
+-#define TIMER_CPUMASK		0x0007FFFF
+-#define TIMER_MIGRATING		0x00080000
++#define TIMER_CPUMASK		0x0003FFFF
++#define TIMER_MIGRATING		0x00040000
+ #define TIMER_BASEMASK		(TIMER_CPUMASK | TIMER_MIGRATING)
+-#define TIMER_DEFERRABLE	0x00100000
++#define TIMER_DEFERRABLE	0x00080000
++#define TIMER_PINNED		0x00100000
+ #define TIMER_IRQSAFE		0x00200000
++#define TIMER_ARRAYSHIFT	22
++#define TIMER_ARRAYMASK		0xFFC00000
+ 
+ #define __TIMER_INITIALIZER(_function, _expires, _data, _flags) { \
+ 		.entry = { .next = TIMER_ENTRY_STATIC },	\
+@@ -70,7 +72,6 @@ struct timer_list {
+ 		.expires = (_expires),				\
+ 		.data = (_data),				\
+ 		.flags = (_flags),				\
+-		.slack = -1,					\
+ 		__TIMER_LOCKDEP_MAP_INITIALIZER(		\
+ 			__FILE__ ":" __stringify(__LINE__))	\
+ 	}
+@@ -78,9 +79,15 @@ struct timer_list {
+ #define TIMER_INITIALIZER(_function, _expires, _data)		\
+ 	__TIMER_INITIALIZER((_function), (_expires), (_data), 0)
+ 
++#define TIMER_PINNED_INITIALIZER(_function, _expires, _data)	\
++	__TIMER_INITIALIZER((_function), (_expires), (_data), TIMER_PINNED)
++
+ #define TIMER_DEFERRED_INITIALIZER(_function, _expires, _data)	\
+ 	__TIMER_INITIALIZER((_function), (_expires), (_data), TIMER_DEFERRABLE)
+ 
++#define TIMER_PINNED_DEFERRED_INITIALIZER(_function, _expires, _data)	\
++	__TIMER_INITIALIZER((_function), (_expires), (_data), TIMER_DEFERRABLE | TIMER_PINNED)
++
+ #define DEFINE_TIMER(_name, _function, _expires, _data)		\
+ 	struct timer_list _name =				\
+ 		TIMER_INITIALIZER(_function, _expires, _data)
+@@ -124,8 +131,12 @@ static inline void init_timer_on_stack_key(struct timer_list *timer,
+ 
+ #define init_timer(timer)						\
+ 	__init_timer((timer), 0)
++#define init_timer_pinned(timer)					\
++	__init_timer((timer), TIMER_PINNED)
+ #define init_timer_deferrable(timer)					\
+ 	__init_timer((timer), TIMER_DEFERRABLE)
++#define init_timer_pinned_deferrable(timer)				\
++	__init_timer((timer), TIMER_DEFERRABLE | TIMER_PINNED)
+ #define init_timer_on_stack(timer)					\
+ 	__init_timer_on_stack((timer), 0)
+ 
+@@ -145,10 +156,20 @@ static inline void init_timer_on_stack_key(struct timer_list *timer,
+ 
+ #define setup_timer(timer, fn, data)					\
+ 	__setup_timer((timer), (fn), (data), 0)
++#define setup_pinned_timer(timer, fn, data)				\
++	__setup_timer((timer), (fn), (data), TIMER_PINNED)
++#define setup_deferrable_timer(timer, fn, data)				\
++	__setup_timer((timer), (fn), (data), TIMER_DEFERRABLE)
++#define setup_pinned_deferrable_timer(timer, fn, data)			\
++	__setup_timer((timer), (fn), (data), TIMER_DEFERRABLE | TIMER_PINNED)
+ #define setup_timer_on_stack(timer, fn, data)				\
+ 	__setup_timer_on_stack((timer), (fn), (data), 0)
++#define setup_pinned_timer_on_stack(timer, fn, data)			\
++	__setup_timer_on_stack((timer), (fn), (data), TIMER_PINNED)
+ #define setup_deferrable_timer_on_stack(timer, fn, data)		\
+ 	__setup_timer_on_stack((timer), (fn), (data), TIMER_DEFERRABLE)
++#define setup_pinned_deferrable_timer_on_stack(timer, fn, data)		\
++	__setup_timer_on_stack((timer), (fn), (data), TIMER_DEFERRABLE | TIMER_PINNED)
+ 
+ /**
+  * timer_pending - is a timer pending?
+@@ -169,12 +190,7 @@ extern void add_timer_on(struct timer_list *timer, int cpu);
+ extern int del_timer(struct timer_list * timer);
+ extern int mod_timer(struct timer_list *timer, unsigned long expires);
+ extern int mod_timer_pending(struct timer_list *timer, unsigned long expires);
+-extern int mod_timer_pinned(struct timer_list *timer, unsigned long expires);
+ 
+-extern void set_timer_slack(struct timer_list *time, int slack_hz);
+-
+-#define TIMER_NOT_PINNED	0
+-#define TIMER_PINNED		1
+ /*
+  * The jiffies value which is added to now, when there is no timer
+  * in the timer wheel:
+@@ -225,7 +241,7 @@ extern void add_timer(struct timer_list *timer);
+ 
+ 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)
+diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
+index 0810f81b6db2..682bfdf20f16 100644
+--- a/include/linux/trace_events.h
++++ b/include/linux/trace_events.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 TRACE_EVENT_TYPE_MAX						\
+diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h
+index 349557825428..1d65e4f0668e 100644
+--- a/include/linux/uaccess.h
++++ b/include/linux/uaccess.h
+@@ -24,6 +24,7 @@ static __always_inline void pagefault_disabled_dec(void)
+  */
+ static inline void pagefault_disable(void)
+ {
++	migrate_disable();
+ 	pagefault_disabled_inc();
+ 	/*
+ 	 * make sure to have issued the store before a pagefault
+@@ -40,6 +41,7 @@ static inline void pagefault_enable(void)
+ 	 */
+ 	barrier();
+ 	pagefault_disabled_dec();
++	migrate_enable();
+ }
+ 
+ /*
+diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h
+index 4a29c75b146e..0a294e950df8 100644
+--- a/include/linux/uprobes.h
++++ b/include/linux/uprobes.h
+@@ -27,6 +27,7 @@
+ #include <linux/errno.h>
+ #include <linux/rbtree.h>
+ #include <linux/types.h>
++#include <linux/wait.h>
+ 
+ struct vm_area_struct;
+ struct mm_struct;
+diff --git a/include/linux/vmstat.h b/include/linux/vmstat.h
+index 73fae8c4a5fb..de8a124fd65d 100644
+--- a/include/linux/vmstat.h
++++ b/include/linux/vmstat.h
+@@ -33,7 +33,9 @@ DECLARE_PER_CPU(struct vm_event_state, vm_event_states);
+  */
+ static inline void __count_vm_event(enum vm_event_item item)
+ {
++	preempt_disable_rt();
+ 	raw_cpu_inc(vm_event_states.event[item]);
++	preempt_enable_rt();
+ }
+ 
+ static inline void count_vm_event(enum vm_event_item item)
+@@ -43,7 +45,9 @@ static inline void count_vm_event(enum vm_event_item item)
+ 
+ static inline void __count_vm_events(enum vm_event_item item, long delta)
+ {
++	preempt_disable_rt();
+ 	raw_cpu_add(vm_event_states.event[item], delta);
++	preempt_enable_rt();
+ }
+ 
+ static inline void count_vm_events(enum vm_event_item item, long delta)
+diff --git a/include/linux/wait.h b/include/linux/wait.h
+index 27d7a0ab5da3..7b3542de6db2 100644
+--- a/include/linux/wait.h
++++ b/include/linux/wait.h
+@@ -8,6 +8,7 @@
+ #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);
+diff --git a/include/net/dst.h b/include/net/dst.h
+index 5c98443c1c9e..22b81c7cec27 100644
+--- a/include/net/dst.h
++++ b/include/net/dst.h
+@@ -449,7 +449,7 @@ static inline void dst_confirm(struct dst_entry *dst)
+ 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;
+diff --git a/include/net/neighbour.h b/include/net/neighbour.h
+index 8b683841e574..bf656008f6e7 100644
+--- a/include/net/neighbour.h
++++ b/include/net/neighbour.h
+@@ -446,7 +446,7 @@ static inline int neigh_hh_bridge(struct hh_cache *hh, struct sk_buff *skb)
+ }
+ #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;
+@@ -501,7 +501,7 @@ 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;
+diff --git a/include/net/netns/ipv4.h b/include/net/netns/ipv4.h
+index a69cde3ce460..bee40aadee1f 100644
+--- a/include/net/netns/ipv4.h
++++ b/include/net/netns/ipv4.h
+@@ -70,6 +70,7 @@ 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;
+diff --git a/include/trace/events/hist.h b/include/trace/events/hist.h
+new file mode 100644
+index 000000000000..f7710de1b1f3
+--- /dev/null
++++ b/include/trace/events/hist.h
+@@ -0,0 +1,73 @@
++#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)
++#define trace_preemptirqsoff_hist_rcuidle(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>
+diff --git a/include/trace/events/latency_hist.h b/include/trace/events/latency_hist.h
+new file mode 100644
+index 000000000000..d3f2fbd560b1
+--- /dev/null
++++ b/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 */
+diff --git a/init/Kconfig b/init/Kconfig
+index 0dfd09d54c65..a74c5a0d8376 100644
+--- a/init/Kconfig
++++ b/init/Kconfig
+@@ -494,7 +494,7 @@ config TINY_RCU
+ 
+ config RCU_EXPERT
+ 	bool "Make expert-level adjustments to RCU configuration"
+-	default n
++	default y if PREEMPT_RT_FULL
+ 	help
+ 	  This option needs to be enabled if you wish to make
+ 	  expert-level adjustments to RCU configuration.  By default,
+@@ -610,7 +610,7 @@ config RCU_FANOUT_LEAF
+ 
+ config RCU_FAST_NO_HZ
+ 	bool "Accelerate last non-dyntick-idle CPU's grace periods"
+-	depends on NO_HZ_COMMON && SMP && RCU_EXPERT
++	depends on NO_HZ_COMMON && SMP && RCU_EXPERT && !PREEMPT_RT_FULL
+ 	default n
+ 	help
+ 	  This option permits CPUs to enter dynticks-idle state even if
+@@ -637,7 +637,7 @@ config TREE_RCU_TRACE
+ config RCU_BOOST
+ 	bool "Enable RCU priority boosting"
+ 	depends on RT_MUTEXES && PREEMPT_RCU && RCU_EXPERT
+-	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.
+@@ -1029,6 +1029,7 @@ 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
+@@ -1717,6 +1718,7 @@ 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
+@@ -1735,6 +1737,7 @@ 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
+@@ -1744,7 +1747,7 @@ endchoice
+ 
+ config SLUB_CPU_PARTIAL
+ 	default y
+-	depends on SLUB && SMP
++	depends on SLUB && SMP && !PREEMPT_RT_FULL
+ 	bool "SLUB per cpu partial cache"
+ 	help
+ 	  Per cpu partial caches accellerate objects allocation and freeing
+diff --git a/init/Makefile b/init/Makefile
+index 7bc47ee31c36..88cf473554e0 100644
+--- a/init/Makefile
++++ b/init/Makefile
+@@ -33,4 +33,4 @@ $(obj)/version.o: include/generated/compile.h
+ include/generated/compile.h: FORCE
+ 	@$($(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)"
+diff --git a/init/main.c b/init/main.c
+index b3c6e363ae18..920f9ebd3d95 100644
+--- a/init/main.c
++++ b/init/main.c
+@@ -507,6 +507,7 @@ asmlinkage __visible void __init start_kernel(void)
+ 	setup_command_line(command_line);
+ 	setup_nr_cpu_ids();
+ 	setup_per_cpu_areas();
++	softirq_early_init();
+ 	boot_cpu_state_init();
+ 	smp_prepare_boot_cpu();	/* arch-specific boot-cpu hooks */
+ 
+diff --git a/ipc/msg.c b/ipc/msg.c
+index 1471db9a7e61..b8c5e7f2bebc 100644
+--- a/ipc/msg.c
++++ b/ipc/msg.c
+@@ -183,20 +183,14 @@ static void ss_wakeup(struct list_head *h, int kill)
+ 	}
+ }
+ 
+-static void expunge_all(struct msg_queue *msq, int res)
++static void expunge_all(struct msg_queue *msq, int res,
++			struct wake_q_head *wake_q)
+ {
+ 	struct msg_receiver *msr, *t;
+ 
+ 	list_for_each_entry_safe(msr, t, &msq->q_receivers, r_list) {
+-		msr->r_msg = NULL; /* initialize expunge ordering */
+-		wake_up_process(msr->r_tsk);
+-		/*
+-		 * Ensure that the wakeup is visible before setting r_msg as
+-		 * the receiving end depends on it: either spinning on a nil,
+-		 * or dealing with -EAGAIN cases. See lockless receive part 1
+-		 * and 2 in do_msgrcv().
+-		 */
+-		smp_wmb(); /* barrier (B) */
++
++		wake_q_add(wake_q, msr->r_tsk);
+ 		msr->r_msg = ERR_PTR(res);
+ 	}
+ }
+@@ -213,11 +207,13 @@ static void freeque(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp)
+ {
+ 	struct msg_msg *msg, *t;
+ 	struct msg_queue *msq = container_of(ipcp, struct msg_queue, q_perm);
++	WAKE_Q(wake_q);
+ 
+-	expunge_all(msq, -EIDRM);
++	expunge_all(msq, -EIDRM, &wake_q);
+ 	ss_wakeup(&msq->q_senders, 1);
+ 	msg_rmid(ns, msq);
+ 	ipc_unlock_object(&msq->q_perm);
++	wake_up_q(&wake_q);
+ 	rcu_read_unlock();
+ 
+ 	list_for_each_entry_safe(msg, t, &msq->q_messages, m_list) {
+@@ -342,6 +338,7 @@ static int msgctl_down(struct ipc_namespace *ns, int msqid, int cmd,
+ 	struct kern_ipc_perm *ipcp;
+ 	struct msqid64_ds uninitialized_var(msqid64);
+ 	struct msg_queue *msq;
++	WAKE_Q(wake_q);
+ 	int err;
+ 
+ 	if (cmd == IPC_SET) {
+@@ -389,7 +386,7 @@ static int msgctl_down(struct ipc_namespace *ns, int msqid, int cmd,
+ 		/* sleeping receivers might be excluded by
+ 		 * stricter permissions.
+ 		 */
+-		expunge_all(msq, -EAGAIN);
++		expunge_all(msq, -EAGAIN, &wake_q);
+ 		/* sleeping senders might be able to send
+ 		 * due to a larger queue size.
+ 		 */
+@@ -402,6 +399,7 @@ static int msgctl_down(struct ipc_namespace *ns, int msqid, int cmd,
+ 
+ out_unlock0:
+ 	ipc_unlock_object(&msq->q_perm);
++	wake_up_q(&wake_q);
+ out_unlock1:
+ 	rcu_read_unlock();
+ out_up:
+@@ -566,7 +564,8 @@ static int testmsg(struct msg_msg *msg, long type, int mode)
+ 	return 0;
+ }
+ 
+-static inline int pipelined_send(struct msg_queue *msq, struct msg_msg *msg)
++static inline int pipelined_send(struct msg_queue *msq, struct msg_msg *msg,
++				 struct wake_q_head *wake_q)
+ {
+ 	struct msg_receiver *msr, *t;
+ 
+@@ -577,27 +576,13 @@ static inline int pipelined_send(struct msg_queue *msq, struct msg_msg *msg)
+ 
+ 			list_del(&msr->r_list);
+ 			if (msr->r_maxsize < msg->m_ts) {
+-				/* initialize pipelined send ordering */
+-				msr->r_msg = NULL;
+-				wake_up_process(msr->r_tsk);
+-				/* barrier (B) see barrier comment below */
+-				smp_wmb();
++				wake_q_add(wake_q, msr->r_tsk);
+ 				msr->r_msg = ERR_PTR(-E2BIG);
+ 			} else {
+-				msr->r_msg = NULL;
+ 				msq->q_lrpid = task_pid_vnr(msr->r_tsk);
+ 				msq->q_rtime = get_seconds();
+-				wake_up_process(msr->r_tsk);
+-				/*
+-				 * Ensure that the wakeup is visible before
+-				 * setting r_msg, as the receiving can otherwise
+-				 * exit - once r_msg is set, the receiver can
+-				 * continue. See lockless receive part 1 and 2
+-				 * in do_msgrcv(). Barrier (B).
+-				 */
+-				smp_wmb();
++				wake_q_add(wake_q, msr->r_tsk);
+ 				msr->r_msg = msg;
+-
+ 				return 1;
+ 			}
+ 		}
+@@ -613,6 +598,7 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext,
+ 	struct msg_msg *msg;
+ 	int err;
+ 	struct ipc_namespace *ns;
++	WAKE_Q(wake_q);
+ 
+ 	ns = current->nsproxy->ipc_ns;
+ 
+@@ -698,7 +684,7 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext,
+ 	msq->q_lspid = task_tgid_vnr(current);
+ 	msq->q_stime = get_seconds();
+ 
+-	if (!pipelined_send(msq, msg)) {
++	if (!pipelined_send(msq, msg, &wake_q)) {
+ 		/* no one is waiting for this message, enqueue it */
+ 		list_add_tail(&msg->m_list, &msq->q_messages);
+ 		msq->q_cbytes += msgsz;
+@@ -712,6 +698,7 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext,
+ 
+ out_unlock0:
+ 	ipc_unlock_object(&msq->q_perm);
++	wake_up_q(&wake_q);
+ out_unlock1:
+ 	rcu_read_unlock();
+ 	if (msg != NULL)
+@@ -932,57 +919,25 @@ long do_msgrcv(int msqid, void __user *buf, size_t bufsz, long msgtyp, int msgfl
+ 		rcu_read_lock();
+ 
+ 		/* Lockless receive, part 2:
+-		 * Wait until pipelined_send or expunge_all are outside of
+-		 * wake_up_process(). There is a race with exit(), see
+-		 * ipc/mqueue.c for the details. The correct serialization
+-		 * ensures that a receiver cannot continue without the wakeup
+-		 * being visibible _before_ setting r_msg:
++		 * The work in pipelined_send() and expunge_all():
++		 * - Set pointer to message
++		 * - Queue the receiver task for later wakeup
++		 * - Wake up the process after the lock is dropped.
+ 		 *
+-		 * CPU 0                             CPU 1
+-		 * <loop receiver>
+-		 *   smp_rmb(); (A) <-- pair -.      <waker thread>
+-		 *   <load ->r_msg>           |        msr->r_msg = NULL;
+-		 *                            |        wake_up_process();
+-		 * <continue>                 `------> smp_wmb(); (B)
+-		 *                                     msr->r_msg = msg;
+-		 *
+-		 * Where (A) orders the message value read and where (B) orders
+-		 * the write to the r_msg -- done in both pipelined_send and
+-		 * expunge_all.
++		 * Should the process wake up before this wakeup (due to a
++		 * signal) it will either see the message and continue …
+ 		 */
+-		for (;;) {
+-			/*
+-			 * Pairs with writer barrier in pipelined_send
+-			 * or expunge_all.
+-			 */
+-			smp_rmb(); /* barrier (A) */
+-			msg = (struct msg_msg *)msr_d.r_msg;
+-			if (msg)
+-				break;
+ 
+-			/*
+-			 * The cpu_relax() call is a compiler barrier
+-			 * which forces everything in this loop to be
+-			 * re-loaded.
+-			 */
+-			cpu_relax();
+-		}
+-
+-		/* Lockless receive, part 3:
+-		 * If there is a message or an error then accept it without
+-		 * locking.
+-		 */
++		msg = (struct msg_msg *)msr_d.r_msg;
+ 		if (msg != ERR_PTR(-EAGAIN))
+ 			goto out_unlock1;
+ 
+-		/* Lockless receive, part 3:
+-		 * Acquire the queue spinlock.
+-		 */
++		 /*
++		  * … or see -EAGAIN, acquire the lock to check the message
++		  * again.
++		  */
+ 		ipc_lock_object(&msq->q_perm);
+ 
+-		/* Lockless receive, part 4:
+-		 * Repeat test after acquiring the spinlock.
+-		 */
+ 		msg = (struct msg_msg *)msr_d.r_msg;
+ 		if (msg != ERR_PTR(-EAGAIN))
+ 			goto out_unlock0;
+diff --git a/ipc/sem.c b/ipc/sem.c
+index b3757ea0694b..981a60ac6b6c 100644
+--- a/ipc/sem.c
++++ b/ipc/sem.c
+@@ -697,6 +697,13 @@ static int perform_atomic_semop(struct sem_array *sma, struct sem_queue *q)
+ 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
+@@ -708,6 +715,7 @@ static void wake_up_sem_queue_prepare(struct list_head *pt,
+ 	q->pid = error;
+ 
+ 	list_add_tail(&q->list, pt);
++#endif
+ }
+ 
+ /**
+@@ -721,6 +729,7 @@ static void wake_up_sem_queue_prepare(struct list_head *pt,
+  */
+ static void wake_up_sem_queue_do(struct list_head *pt)
+ {
++#ifndef CONFIG_PREEMPT_RT_BASE
+ 	struct sem_queue *q, *t;
+ 	int did_something;
+ 
+@@ -733,6 +742,7 @@ static void wake_up_sem_queue_do(struct list_head *pt)
+ 	}
+ 	if (did_something)
+ 		preempt_enable();
++#endif
+ }
+ 
+ static void unlink_queue(struct sem_array *sma, struct sem_queue *q)
+diff --git a/kernel/Kconfig.locks b/kernel/Kconfig.locks
+index ebdb0043203a..b9e6aa7e5aa6 100644
+--- a/kernel/Kconfig.locks
++++ b/kernel/Kconfig.locks
+@@ -225,11 +225,11 @@ config ARCH_SUPPORTS_ATOMIC_RMW
+ 
+ config MUTEX_SPIN_ON_OWNER
+ 	def_bool y
+-	depends on SMP && !DEBUG_MUTEXES && ARCH_SUPPORTS_ATOMIC_RMW
++	depends on SMP && !DEBUG_MUTEXES && ARCH_SUPPORTS_ATOMIC_RMW && !PREEMPT_RT_FULL
+ 
+ config RWSEM_SPIN_ON_OWNER
+        def_bool y
+-       depends on SMP && RWSEM_XCHGADD_ALGORITHM && ARCH_SUPPORTS_ATOMIC_RMW
++       depends on SMP && RWSEM_XCHGADD_ALGORITHM && ARCH_SUPPORTS_ATOMIC_RMW && !PREEMPT_RT_FULL
+ 
+ config LOCK_SPIN_ON_OWNER
+        def_bool y
+diff --git a/kernel/Kconfig.preempt b/kernel/Kconfig.preempt
+index 3f9c97419f02..11dbe26a8279 100644
+--- a/kernel/Kconfig.preempt
++++ b/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
+diff --git a/kernel/cgroup.c b/kernel/cgroup.c
+index 86cb5c6e8932..3920f49948f8 100644
+--- a/kernel/cgroup.c
++++ b/kernel/cgroup.c
+@@ -5005,10 +5005,10 @@ static void css_free_rcu_fn(struct rcu_head *rcu_head)
+ 	queue_work(cgroup_destroy_wq, &css->destroy_work);
+ }
+ 
+-static void css_release_work_fn(struct work_struct *work)
++static void css_release_work_fn(struct swork_event *sev)
+ {
+ 	struct cgroup_subsys_state *css =
+-		container_of(work, struct cgroup_subsys_state, destroy_work);
++		container_of(sev, struct cgroup_subsys_state, destroy_swork);
+ 	struct cgroup_subsys *ss = css->ss;
+ 	struct cgroup *cgrp = css->cgroup;
+ 
+@@ -5049,8 +5049,8 @@ static void css_release(struct percpu_ref *ref)
+ 	struct cgroup_subsys_state *css =
+ 		container_of(ref, struct cgroup_subsys_state, refcnt);
+ 
+-	INIT_WORK(&css->destroy_work, css_release_work_fn);
+-	queue_work(cgroup_destroy_wq, &css->destroy_work);
++	INIT_SWORK(&css->destroy_swork, css_release_work_fn);
++	swork_queue(&css->destroy_swork);
+ }
+ 
+ static void init_and_link_css(struct cgroup_subsys_state *css,
+@@ -5694,6 +5694,7 @@ static int __init cgroup_wq_init(void)
+ 	 */
+ 	cgroup_destroy_wq = alloc_workqueue("cgroup_destroy", 0, 1);
+ 	BUG_ON(!cgroup_destroy_wq);
++	BUG_ON(swork_get());
+ 
+ 	/*
+ 	 * Used to destroy pidlists and separate to serve as flush domain.
+diff --git a/kernel/cpu.c b/kernel/cpu.c
+index 3e3f6e49eabb..e4d7491c1c12 100644
+--- a/kernel/cpu.c
++++ b/kernel/cpu.c
+@@ -152,8 +152,8 @@ static struct {
+ #endif
+ } cpu_hotplug = {
+ 	.active_writer = NULL,
+-	.wq = __WAIT_QUEUE_HEAD_INITIALIZER(cpu_hotplug.wq),
+ 	.lock = __MUTEX_INITIALIZER(cpu_hotplug.lock),
++	.wq = __WAIT_QUEUE_HEAD_INITIALIZER(cpu_hotplug.wq),
+ #ifdef CONFIG_DEBUG_LOCK_ALLOC
+ 	.dep_map = {.name = "cpu_hotplug.lock" },
+ #endif
+@@ -166,6 +166,289 @@ static struct {
+ #define cpuhp_lock_acquire()      lock_map_acquire(&cpu_hotplug.dep_map)
+ #define cpuhp_lock_release()      lock_map_release(&cpu_hotplug.dep_map)
+ 
++/**
++ * 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__no_mg(&(hp)->lock)
++# define hotplug_unlock(hp) rt_spin_unlock__no_mg(&(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 = this_cpu_ptr(&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 = this_cpu_ptr(&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 = this_cpu_ptr(&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;
++	set_cpus_allowed_ptr(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)
+ {
+@@ -718,10 +1001,14 @@ static int takedown_cpu(unsigned int cpu)
+ 	else
+ 		synchronize_rcu();
+ 
++	__cpu_unplug_wait(cpu);
+ 	/* Park the smpboot threads */
+ 	kthread_park(per_cpu_ptr(&cpuhp_state, cpu)->thread);
+ 	smpboot_park_threads(cpu);
+ 
++	/* Notifiers are done. Don't let any more tasks pin this CPU. */
++	cpu_unplug_sync(cpu);
++
+ 	/*
+ 	 * Prevent irq alloc/free while the dying cpu reorganizes the
+ 	 * interrupt affinities.
+@@ -807,6 +1094,9 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen,
+ 	struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu);
+ 	int prev_state, ret = 0;
+ 	bool hasdied = false;
++	int mycpu;
++	cpumask_var_t cpumask;
++	cpumask_var_t cpumask_org;
+ 
+ 	if (num_online_cpus() == 1)
+ 		return -EBUSY;
+@@ -814,7 +1104,34 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen,
+ 	if (!cpu_present(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();
++		ret = -EBUSY;
++		goto restore_cpus;
++	}
++
++	migrate_enable();
+ 	cpu_hotplug_begin();
++	ret = cpu_unplug_begin(cpu);
++	if (ret) {
++		printk("cpu_unplug_begin(%d) failed\n", cpu);
++		goto out_cancel;
++	}
+ 
+ 	cpuhp_tasks_frozen = tasks_frozen;
+ 
+@@ -853,10 +1170,15 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen,
+ 
+ 	hasdied = prev_state != st->state && st->state == CPUHP_OFFLINE;
+ out:
++	cpu_unplug_done(cpu);
++out_cancel:
+ 	cpu_hotplug_done();
+ 	/* This post dead nonsense must die */
+ 	if (!ret && hasdied)
+ 		cpu_notify_nofail(CPU_POST_DEAD, cpu);
++restore_cpus:
++	set_cpus_allowed_ptr(current, cpumask_org);
++	free_cpumask_var(cpumask_org);
+ 	return ret;
+ }
+ 
+diff --git a/kernel/debug/kdb/kdb_io.c b/kernel/debug/kdb/kdb_io.c
+index fc1ef736253c..83c666537a7a 100644
+--- a/kernel/debug/kdb/kdb_io.c
++++ b/kernel/debug/kdb/kdb_io.c
+@@ -554,7 +554,6 @@ int vkdb_printf(enum kdb_msgsrc src, const char *fmt, va_list ap)
+ 	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(enum kdb_msgsrc src, const char *fmt, va_list ap)
+ 	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,
+@@ -855,7 +852,6 @@ int vkdb_printf(enum kdb_msgsrc src, const char *fmt, va_list ap)
+ 	} else {
+ 		__release(kdb_printf_lock);
+ 	}
+-	kdb_trap_printk = saved_trap_printk;
+ 	preempt_enable();
+ 	return retlen;
+ }
+@@ -865,9 +861,11 @@ int kdb_printf(const char *fmt, ...)
+ 	va_list ap;
+ 	int r;
+ 
++	kdb_trap_printk++;
+ 	va_start(ap, fmt);
+ 	r = vkdb_printf(KDB_MSGSRC_INTERNAL, fmt, ap);
+ 	va_end(ap);
++	kdb_trap_printk--;
+ 
+ 	return r;
+ }
+diff --git a/kernel/events/core.c b/kernel/events/core.c
+index a69c90cea05d..dc7b7c094abb 100644
+--- a/kernel/events/core.c
++++ b/kernel/events/core.c
+@@ -963,6 +963,7 @@ static void __perf_mux_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu)
+ 	raw_spin_lock_init(&cpuctx->hrtimer_lock);
+ 	hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED);
+ 	timer->function = perf_mux_hrtimer_handler;
++	timer->irqsafe = 1;
+ }
+ 
+ static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx)
+@@ -7261,6 +7262,7 @@ static void perf_swevent_init_hrtimer(struct perf_event *event)
+ 
+ 	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
+diff --git a/kernel/exit.c b/kernel/exit.c
+index 79c7e38a203b..12da2d0ba120 100644
+--- a/kernel/exit.c
++++ b/kernel/exit.c
+@@ -143,7 +143,7 @@ static void __exit_signal(struct task_struct *tsk)
+ 	 * Do this under ->siglock, we can race with another thread
+ 	 * doing sigqueue_free() if we have SIGQUEUE_PREALLOC signals.
+ 	 */
+-	flush_sigqueue(&tsk->pending);
++	flush_task_sigqueue(tsk);
+ 	tsk->sighand = NULL;
+ 	spin_unlock(&sighand->siglock);
+ 
+diff --git a/kernel/fork.c b/kernel/fork.c
+index d277e83ed3e0..18cc63048297 100644
+--- a/kernel/fork.c
++++ b/kernel/fork.c
+@@ -253,7 +253,9 @@ static inline void put_signal_struct(struct signal_struct *sig)
+ 	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);
+@@ -270,7 +272,18 @@ void __put_task_struct(struct task_struct *tsk)
+ 	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) { }
+ 
+@@ -699,6 +712,19 @@ 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.
+  */
+@@ -1228,6 +1254,9 @@ static void rt_mutex_init_task(struct task_struct *p)
+  */
+ 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;
+@@ -1352,6 +1381,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
+ 	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;
+diff --git a/kernel/futex.c b/kernel/futex.c
+index 6555d5459e98..2d572edcac53 100644
+--- a/kernel/futex.c
++++ b/kernel/futex.c
+@@ -874,7 +874,9 @@ void exit_pi_state_list(struct task_struct *curr)
+ 		 * 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;
+ 		}
+ 
+@@ -1269,6 +1271,7 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_q *this,
+ 	struct futex_pi_state *pi_state = this->pi_state;
+ 	u32 uninitialized_var(curval), newval;
+ 	WAKE_Q(wake_q);
++	WAKE_Q(wake_sleeper_q);
+ 	bool deboost;
+ 	int ret = 0;
+ 
+@@ -1335,7 +1338,8 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_q *this,
+ 
+ 	raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock);
+ 
+-	deboost = rt_mutex_futex_unlock(&pi_state->pi_mutex, &wake_q);
++	deboost = rt_mutex_futex_unlock(&pi_state->pi_mutex, &wake_q,
++					&wake_sleeper_q);
+ 
+ 	/*
+ 	 * First unlock HB so the waiter does not spin on it once he got woken
+@@ -1345,6 +1349,7 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_q *this,
+ 	 */
+ 	spin_unlock(&hb->lock);
+ 	wake_up_q(&wake_q);
++	wake_up_q_sleeper(&wake_sleeper_q);
+ 	if (deboost)
+ 		rt_mutex_adjust_prio(current);
+ 
+@@ -1894,6 +1899,16 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags,
+ 				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;
++				put_pi_state(pi_state);
++				continue;
+ 			} else if (ret) {
+ 				/*
+ 				 * rt_mutex_start_proxy_lock() detected a
+@@ -2784,7 +2799,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
+ 	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;
+@@ -2809,10 +2824,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
+ 	 * The waiter is allocated on our stack, manipulated by the requeue
+ 	 * code while we sleep on uaddr.
+ 	 */
+-	debug_rt_mutex_init_waiter(&rt_waiter);
+-	RB_CLEAR_NODE(&rt_waiter.pi_tree_entry);
+-	RB_CLEAR_NODE(&rt_waiter.tree_entry);
+-	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))
+@@ -2843,20 +2855,55 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
+ 	/* Queue the futex_q, drop the hb lock, wait for wakeup. */
+ 	futex_wait_queue_me(hb, &q, to);
+ 
+-	spin_lock(&hb->lock);
+-	ret = handle_early_requeue_pi_wakeup(hb, &q, &key2, to);
+-	spin_unlock(&hb->lock);
+-	if (ret)
+-		goto out_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) {
+@@ -2865,14 +2912,15 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
+ 		 * did a lock-steal - fix up the PI-state in that case.
+ 		 */
+ 		if (q.pi_state && (q.pi_state->owner != current)) {
+-			spin_lock(q.lock_ptr);
++			spin_lock(&hb2->lock);
++			BUG_ON(&hb2->lock != q.lock_ptr);
+ 			ret = fixup_pi_state_owner(uaddr2, &q, current);
+ 			/*
+ 			 * Drop the reference to the pi state which
+ 			 * the requeue_pi() code acquired for us.
+ 			 */
+ 			put_pi_state(q.pi_state);
+-			spin_unlock(q.lock_ptr);
++			spin_unlock(&hb2->lock);
+ 		}
+ 	} else {
+ 		/*
+@@ -2885,7 +2933,8 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
+ 		ret = rt_mutex_finish_proxy_lock(pi_mutex, to, &rt_waiter);
+ 		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.
+diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
+index a15b5485b446..28c39c16f989 100644
+--- a/kernel/irq/handle.c
++++ b/kernel/irq/handle.c
+@@ -134,6 +134,8 @@ void __irq_wake_thread(struct irq_desc *desc, struct irqaction *action)
+ 
+ irqreturn_t handle_irq_event_percpu(struct irq_desc *desc)
+ {
++	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;
+ 	struct irqaction *action;
+@@ -174,7 +176,11 @@ irqreturn_t handle_irq_event_percpu(struct irq_desc *desc)
+ 		retval |= res;
+ 	}
+ 
+-	add_interrupt_randomness(irq, flags);
++#ifdef CONFIG_PREEMPT_RT_FULL
++	desc->random_ip = ip;
++#else
++	add_interrupt_randomness(irq, flags, ip);
++#endif
+ 
+ 	if (!noirqdebug)
+ 		note_interrupt(desc, retval);
+diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
+index cc1cc641d653..f5e9fd5408d6 100644
+--- a/kernel/irq/manage.c
++++ b/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_irqthreads(char *arg)
+ 	return 0;
+ }
+ early_param("threadirqs", setup_forced_irqthreads);
++# endif
+ #endif
+ 
+ static void __synchronize_hardirq(struct irq_desc *desc)
+@@ -179,6 +181,62 @@ static inline void
+ irq_get_pending(struct cpumask *mask, struct irq_desc *desc) { }
+ #endif
+ 
++#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_do_set_affinity(struct irq_data *data, const struct cpumask *mask,
+ 			bool force)
+ {
+@@ -218,7 +276,17 @@ int irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask,
+ 
+ 	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);
+ 
+@@ -256,10 +324,8 @@ int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m)
+ }
+ 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;
+@@ -281,6 +347,13 @@ static void irq_affinity_notify(struct work_struct *work)
+ 	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
+@@ -310,6 +383,8 @@ irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify)
+ 		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);
+@@ -863,7 +938,15 @@ irq_forced_thread_fn(struct irq_desc *desc, struct irqaction *action)
+ 	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;
+ }
+ 
+@@ -960,6 +1043,12 @@ static int irq_thread(void *data)
+ 		if (action_ret == IRQ_WAKE_THREAD)
+ 			irq_wake_secondary(desc, action);
+ 
++#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);
+ 	}
+ 
+@@ -1313,6 +1402,9 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
+ 			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(desc, mask);
+ 
+@@ -1998,7 +2090,7 @@ EXPORT_SYMBOL_GPL(irq_get_irqchip_state);
+  *	This call sets the internal irqchip state of an interrupt,
+  *	depending on the value of @which.
+  *
+- *	This function should be called with preemption disabled if the
++ *	This function should be called with migration disabled if the
+  *	interrupt controller has per-cpu registers.
+  */
+ int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
+diff --git a/kernel/irq/settings.h b/kernel/irq/settings.h
+index 320579d89091..2df2d4445b1e 100644
+--- a/kernel/irq/settings.h
++++ b/kernel/irq/settings.h
+@@ -16,6 +16,7 @@ enum {
+ 	_IRQ_PER_CPU_DEVID	= IRQ_PER_CPU_DEVID,
+ 	_IRQ_IS_POLLED		= IRQ_IS_POLLED,
+ 	_IRQ_DISABLE_UNLAZY	= IRQ_DISABLE_UNLAZY,
++	_IRQ_NO_SOFTIRQ_CALL	= IRQ_NO_SOFTIRQ_CALL,
+ 	_IRQF_MODIFY_MASK	= IRQF_MODIFY_MASK,
+ };
+ 
+@@ -30,6 +31,7 @@ enum {
+ #define IRQ_PER_CPU_DEVID	GOT_YOU_MORON
+ #define IRQ_IS_POLLED		GOT_YOU_MORON
+ #define IRQ_DISABLE_UNLAZY	GOT_YOU_MORON
++#define IRQ_NO_SOFTIRQ_CALL	GOT_YOU_MORON
+ #undef IRQF_MODIFY_MASK
+ #define IRQF_MODIFY_MASK	GOT_YOU_MORON
+ 
+@@ -40,6 +42,16 @@ irq_settings_clr_and_set(struct irq_desc *desc, u32 clr, u32 set)
+ 	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;
+diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c
+index 5707f97a3e6a..73f38dc7a7fb 100644
+--- a/kernel/irq/spurious.c
++++ b/kernel/irq/spurious.c
+@@ -442,6 +442,10 @@ MODULE_PARM_DESC(noirqdebug, "Disable irq lockup detection when true");
+ 
+ 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");
+@@ -454,6 +458,10 @@ 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");
+diff --git a/kernel/irq_work.c b/kernel/irq_work.c
+index bcf107ce0854..2899ba0d23d1 100644
+--- a/kernel/irq_work.c
++++ b/kernel/irq_work.c
+@@ -17,6 +17,7 @@
+ #include <linux/cpu.h>
+ #include <linux/notifier.h>
+ #include <linux/smp.h>
++#include <linux/interrupt.h>
+ #include <asm/processor.h>
+ 
+ 
+@@ -65,6 +66,8 @@ void __weak arch_irq_work_raise(void)
+  */
+ bool irq_work_queue_on(struct irq_work *work, int cpu)
+ {
++	struct llist_head *list;
++
+ 	/* All work should have been flushed before going offline */
+ 	WARN_ON_ONCE(cpu_is_offline(cpu));
+ 
+@@ -75,7 +78,12 @@ bool irq_work_queue_on(struct irq_work *work, int cpu)
+ 	if (!irq_work_claim(work))
+ 		return false;
+ 
+-	if (llist_add(&work->llnode, &per_cpu(raised_list, cpu)))
++	if (IS_ENABLED(CONFIG_PREEMPT_RT_FULL) && !(work->flags & IRQ_WORK_HARD_IRQ))
++		list = &per_cpu(lazy_list, cpu);
++	else
++		list = &per_cpu(raised_list, cpu);
++
++	if (llist_add(&work->llnode, list))
+ 		arch_send_call_function_single_ipi(cpu);
+ 
+ 	return true;
+@@ -86,6 +94,9 @@ EXPORT_SYMBOL_GPL(irq_work_queue_on);
+ /* Enqueue the irq work @work on the current CPU */
+ bool irq_work_queue(struct irq_work *work)
+ {
++	struct llist_head *list;
++	bool lazy_work, realtime = IS_ENABLED(CONFIG_PREEMPT_RT_FULL);
++
+ 	/* Only queue if not already pending */
+ 	if (!irq_work_claim(work))
+ 		return false;
+@@ -93,13 +104,15 @@ bool irq_work_queue(struct irq_work *work)
+ 	/* Queue the entry and raise the IPI if needed. */
+ 	preempt_disable();
+ 
+-	/* If the work is "lazy", handle it from next tick if any */
+-	if (work->flags & IRQ_WORK_LAZY) {
+-		if (llist_add(&work->llnode, this_cpu_ptr(&lazy_list)) &&
+-		    tick_nohz_tick_stopped())
+-			arch_irq_work_raise();
+-	} else {
+-		if (llist_add(&work->llnode, this_cpu_ptr(&raised_list)))
++	lazy_work = work->flags & IRQ_WORK_LAZY;
++
++	if (lazy_work || (realtime && !(work->flags & IRQ_WORK_HARD_IRQ)))
++		list = this_cpu_ptr(&lazy_list);
++	else
++		list = this_cpu_ptr(&raised_list);
++
++	if (llist_add(&work->llnode, list)) {
++		if (!lazy_work || tick_nohz_tick_stopped())
+ 			arch_irq_work_raise();
+ 	}
+ 
+@@ -116,9 +129,8 @@ bool irq_work_needs_cpu(void)
+ 	raised = this_cpu_ptr(&raised_list);
+ 	lazy = this_cpu_ptr(&lazy_list);
+ 
+-	if (llist_empty(raised) || arch_irq_work_has_interrupt())
+-		if (llist_empty(lazy))
+-			return false;
++	if (llist_empty(raised) && llist_empty(lazy))
++		return false;
+ 
+ 	/* All work should have been flushed before going offline */
+ 	WARN_ON_ONCE(cpu_is_offline(smp_processor_id()));
+@@ -132,7 +144,7 @@ static void irq_work_run_list(struct llist_head *list)
+ 	struct irq_work *work;
+ 	struct llist_node *llnode;
+ 
+-	BUG_ON(!irqs_disabled());
++	BUG_ON_NONRT(!irqs_disabled());
+ 
+ 	if (llist_empty(list))
+ 		return;
+@@ -169,7 +181,16 @@ static void irq_work_run_list(struct llist_head *list)
+ void irq_work_run(void)
+ {
+ 	irq_work_run_list(this_cpu_ptr(&raised_list));
+-	irq_work_run_list(this_cpu_ptr(&lazy_list));
++	if (IS_ENABLED(CONFIG_PREEMPT_RT_FULL)) {
++		/*
++		 * NOTE: we raise softirq via IPI for safety,
++		 * and execute in irq_work_tick() to move the
++		 * overhead from hard to soft irq context.
++		 */
++		if (!llist_empty(this_cpu_ptr(&lazy_list)))
++			raise_softirq(TIMER_SOFTIRQ);
++	} else
++		irq_work_run_list(this_cpu_ptr(&lazy_list));
+ }
+ EXPORT_SYMBOL_GPL(irq_work_run);
+ 
+@@ -179,8 +200,17 @@ void irq_work_tick(void)
+ 
+ 	if (!llist_empty(raised) && !arch_irq_work_has_interrupt())
+ 		irq_work_run_list(raised);
++
++	if (!IS_ENABLED(CONFIG_PREEMPT_RT_FULL))
++		irq_work_run_list(this_cpu_ptr(&lazy_list));
++}
++
++#if defined(CONFIG_IRQ_WORK) && defined(CONFIG_PREEMPT_RT_FULL)
++void irq_work_tick_soft(void)
++{
+ 	irq_work_run_list(this_cpu_ptr(&lazy_list));
+ }
++#endif
+ 
+ /*
+  * Synchronize against the irq_work @entry, ensures the entry is not
+diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c
+index 152da4a48867..9fe46356ed47 100644
+--- a/kernel/ksysfs.c
++++ b/kernel/ksysfs.c
+@@ -136,6 +136,15 @@ KERNEL_ATTR_RO(vmcoreinfo);
+ 
+ #endif /* CONFIG_KEXEC_CORE */
+ 
++#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)
+@@ -225,6 +234,9 @@ static struct attribute * kernel_attrs[] = {
+ 	&rcu_expedited_attr.attr,
+ 	&rcu_normal_attr.attr,
+ #endif
++#ifdef CONFIG_PREEMPT_RT_FULL
++	&realtime_attr.attr,
++#endif
+ 	NULL
+ };
+ 
+diff --git a/kernel/locking/Makefile b/kernel/locking/Makefile
+index 31322a4275cd..c6bba9299d8b 100644
+--- a/kernel/locking/Makefile
++++ b/kernel/locking/Makefile
+@@ -2,7 +2,7 @@
+ # and is generally not a function of system call inputs.
+ KCOV_INSTRUMENT		:= n
+ 
+-obj-y += mutex.o semaphore.o rwsem.o percpu-rwsem.o
++obj-y += semaphore.o percpu-rwsem.o
+ 
+ ifdef CONFIG_FUNCTION_TRACER
+ CFLAGS_REMOVE_lockdep.o = $(CC_FLAGS_FTRACE)
+@@ -11,7 +11,11 @@ CFLAGS_REMOVE_mutex-debug.o = $(CC_FLAGS_FTRACE)
+ CFLAGS_REMOVE_rtmutex-debug.o = $(CC_FLAGS_FTRACE)
+ endif
+ 
++ifneq ($(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
+@@ -25,7 +29,10 @@ obj-$(CONFIG_RT_MUTEXES) += rtmutex.o
+ obj-$(CONFIG_DEBUG_RT_MUTEXES) += rtmutex-debug.o
+ obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock.o
+ obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock_debug.o
++ifneq ($(CONFIG_PREEMPT_RT_FULL),y)
+ obj-$(CONFIG_RWSEM_GENERIC_SPINLOCK) += rwsem-spinlock.o
+ obj-$(CONFIG_RWSEM_XCHGADD_ALGORITHM) += rwsem-xadd.o
++endif
++obj-$(CONFIG_PREEMPT_RT_FULL) += rt.o
+ obj-$(CONFIG_QUEUED_RWLOCKS) += qrwlock.o
+ obj-$(CONFIG_LOCK_TORTURE_TEST) += locktorture.o
+diff --git a/kernel/locking/lglock.c b/kernel/locking/lglock.c
+index 951cfcd10b4a..57e0ea72c28a 100644
+--- a/kernel/locking/lglock.c
++++ b/kernel/locking/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__no_mg(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);
+ 
+@@ -68,30 +86,30 @@ void lg_double_lock(struct lglock *lg, int cpu1, int cpu2)
+ 	if (cpu2 < cpu1)
+ 		swap(cpu1, cpu2);
+ 
+-	preempt_disable();
++	preempt_disable_nort();
+ 	lock_acquire_shared(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_);
+-	arch_spin_lock(per_cpu_ptr(lg->lock, cpu1));
+-	arch_spin_lock(per_cpu_ptr(lg->lock, cpu2));
++	lg_do_lock(per_cpu_ptr(lg->lock, cpu1));
++	lg_do_lock(per_cpu_ptr(lg->lock, cpu2));
+ }
+ 
+ void lg_double_unlock(struct lglock *lg, int cpu1, int cpu2)
+ {
+ 	lock_release(&lg->lock_dep_map, 1, _RET_IP_);
+-	arch_spin_unlock(per_cpu_ptr(lg->lock, cpu1));
+-	arch_spin_unlock(per_cpu_ptr(lg->lock, cpu2));
+-	preempt_enable();
++	lg_do_unlock(per_cpu_ptr(lg->lock, cpu1));
++	lg_do_unlock(per_cpu_ptr(lg->lock, cpu2));
++	preempt_enable_nort();
+ }
+ 
+ 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);
+@@ -102,10 +120,35 @@ 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);
++
++#ifdef CONFIG_PREEMPT_RT_FULL
++/*
++ * HACK: If you use this, you get to keep the pieces.
++ * Used in queue_stop_cpus_work() when stop machinery
++ * is called from inactive CPU, so we can't schedule.
++ */
++# define lg_do_trylock_relax(l)			\
++	do {					\
++		while (!__rt_spin_trylock(l))	\
++			cpu_relax();		\
++	} while (0)
++
++void lg_global_trylock_relax(struct lglock *lg)
++{
++	int i;
++
++	lock_acquire_exclusive(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_);
++	for_each_possible_cpu(i) {
++		lg_lock_ptr *lock;
++		lock = per_cpu_ptr(lg->lock, i);
++		lg_do_trylock_relax(lock);
++	}
++}
++#endif
+diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
+index 78c1c0ee6dc1..839175acc1c6 100644
+--- a/kernel/locking/lockdep.c
++++ b/kernel/locking/lockdep.c
+@@ -3648,6 +3648,7 @@ static void check_flags(unsigned long flags)
+ 		}
+ 	}
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
+ 	/*
+ 	 * We dont accurately track softirq state in e.g.
+ 	 * hardirq contexts (such as on 4KSTACKS), so only
+@@ -3662,6 +3663,7 @@ static void check_flags(unsigned long flags)
+ 			DEBUG_LOCKS_WARN_ON(!current->softirqs_enabled);
+ 		}
+ 	}
++#endif
+ 
+ 	if (!debug_locks)
+ 		print_irqtrace_events(current);
+diff --git a/kernel/locking/locktorture.c b/kernel/locking/locktorture.c
+index 8ef1919d63b2..291fc19e28e0 100644
+--- a/kernel/locking/locktorture.c
++++ b/kernel/locking/locktorture.c
+@@ -26,7 +26,6 @@
+ #include <linux/kthread.h>
+ #include <linux/sched/rt.h>
+ #include <linux/spinlock.h>
+-#include <linux/rwlock.h>
+ #include <linux/mutex.h>
+ #include <linux/rwsem.h>
+ #include <linux/smp.h>
+diff --git a/kernel/locking/rt.c b/kernel/locking/rt.c
+new file mode 100644
+index 000000000000..d4ab61c1848b
+--- /dev/null
++++ b/kernel/locking/rt.c
+@@ -0,0 +1,474 @@
++/*
++ * 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);
++	if (ret)
++		mutex_release(&lock->dep_map, 1, _RET_IP_);
++	return ret;
++}
++EXPORT_SYMBOL(_mutex_lock_interruptible);
++
++int __lockfunc _mutex_lock_killable(struct mutex *lock)
++{
++	int ret;
++
++	mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
++	ret = rt_mutex_lock_killable(&lock->lock);
++	if (ret)
++		mutex_release(&lock->dep_map, 1, _RET_IP_);
++	return ret;
++}
++EXPORT_SYMBOL(_mutex_lock_killable);
++
++#ifdef CONFIG_DEBUG_LOCK_ALLOC
++void __lockfunc _mutex_lock_nested(struct mutex *lock, int subclass)
++{
++	mutex_acquire_nest(&lock->dep_map, subclass, 0, NULL, _RET_IP_);
++	rt_mutex_lock(&lock->lock);
++}
++EXPORT_SYMBOL(_mutex_lock_nested);
++
++void __lockfunc _mutex_lock_nest_lock(struct mutex *lock, struct lockdep_map *nest)
++{
++	mutex_acquire_nest(&lock->dep_map, 0, 0, nest, _RET_IP_);
++	rt_mutex_lock(&lock->lock);
++}
++EXPORT_SYMBOL(_mutex_lock_nest_lock);
++
++int __lockfunc _mutex_lock_interruptible_nested(struct mutex *lock, int subclass)
++{
++	int ret;
++
++	mutex_acquire_nest(&lock->dep_map, subclass, 0, NULL, _RET_IP_);
++	ret = rt_mutex_lock_interruptible(&lock->lock);
++	if (ret)
++		mutex_release(&lock->dep_map, 1, _RET_IP_);
++	return ret;
++}
++EXPORT_SYMBOL(_mutex_lock_interruptible_nested);
++
++int __lockfunc _mutex_lock_killable_nested(struct mutex *lock, int subclass)
++{
++	int ret;
++
++	mutex_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
++	ret = rt_mutex_lock_killable(&lock->lock);
++	if (ret)
++		mutex_release(&lock->dep_map, 1, _RET_IP_);
++	return ret;
++}
++EXPORT_SYMBOL(_mutex_lock_killable_nested);
++#endif
++
++int __lockfunc _mutex_trylock(struct mutex *lock)
++{
++	int ret = rt_mutex_trylock(&lock->lock);
++
++	if (ret)
++		mutex_acquire(&lock->dep_map, 0, 1, _RET_IP_);
++
++	return ret;
++}
++EXPORT_SYMBOL(_mutex_trylock);
++
++void __lockfunc _mutex_unlock(struct mutex *lock)
++{
++	mutex_release(&lock->dep_map, 1, _RET_IP_);
++	rt_mutex_unlock(&lock->lock);
++}
++EXPORT_SYMBOL(_mutex_unlock);
++
++/*
++ * rwlock_t functions
++ */
++int __lockfunc rt_write_trylock(rwlock_t *rwlock)
++{
++	int ret;
++
++	migrate_disable();
++	ret = rt_mutex_trylock(&rwlock->lock);
++	if (ret)
++		rwlock_acquire(&rwlock->dep_map, 0, 1, _RET_IP_);
++	else
++		migrate_enable();
++
++	return ret;
++}
++EXPORT_SYMBOL(rt_write_trylock);
++
++int __lockfunc rt_write_trylock_irqsave(rwlock_t *rwlock, unsigned long *flags)
++{
++	int ret;
++
++	*flags = 0;
++	ret = rt_write_trylock(rwlock);
++	return ret;
++}
++EXPORT_SYMBOL(rt_write_trylock_irqsave);
++
++int __lockfunc rt_read_trylock(rwlock_t *rwlock)
++{
++	struct rt_mutex *lock = &rwlock->lock;
++	int ret = 1;
++
++	/*
++	 * recursive read locks succeed when current owns the lock,
++	 * but not when read_depth == 0 which means that the lock is
++	 * write locked.
++	 */
++	if (rt_mutex_owner(lock) != current) {
++		migrate_disable();
++		ret = rt_mutex_trylock(lock);
++		if (ret)
++			rwlock_acquire(&rwlock->dep_map, 0, 1, _RET_IP_);
++		else
++			migrate_enable();
++
++	} else if (!rwlock->read_depth) {
++		ret = 0;
++	}
++
++	if (ret)
++		rwlock->read_depth++;
++
++	return ret;
++}
++EXPORT_SYMBOL(rt_read_trylock);
++
++void __lockfunc rt_write_lock(rwlock_t *rwlock)
++{
++	rwlock_acquire(&rwlock->dep_map, 0, 0, _RET_IP_);
++	__rt_spin_lock(&rwlock->lock);
++}
++EXPORT_SYMBOL(rt_write_lock);
++
++void __lockfunc rt_read_lock(rwlock_t *rwlock)
++{
++	struct rt_mutex *lock = &rwlock->lock;
++
++
++	/*
++	 * recursive read locks succeed when current owns the lock
++	 */
++	if (rt_mutex_owner(lock) != current) {
++		rwlock_acquire(&rwlock->dep_map, 0, 0, _RET_IP_);
++		__rt_spin_lock(lock);
++	}
++	rwlock->read_depth++;
++}
++
++EXPORT_SYMBOL(rt_read_lock);
++
++void __lockfunc rt_write_unlock(rwlock_t *rwlock)
++{
++	/* NOTE: we always pass in '1' for nested, for simplicity */
++	rwlock_release(&rwlock->dep_map, 1, _RET_IP_);
++	__rt_spin_unlock(&rwlock->lock);
++	migrate_enable();
++}
++EXPORT_SYMBOL(rt_write_unlock);
++
++void __lockfunc rt_read_unlock(rwlock_t *rwlock)
++{
++	/* Release the lock only when read_depth is down to 0 */
++	if (--rwlock->read_depth == 0) {
++		rwlock_release(&rwlock->dep_map, 1, _RET_IP_);
++		__rt_spin_unlock(&rwlock->lock);
++		migrate_enable();
++	}
++}
++EXPORT_SYMBOL(rt_read_unlock);
++
++unsigned long __lockfunc rt_write_lock_irqsave(rwlock_t *rwlock)
++{
++	rt_write_lock(rwlock);
++
++	return 0;
++}
++EXPORT_SYMBOL(rt_write_lock_irqsave);
++
++unsigned long __lockfunc rt_read_lock_irqsave(rwlock_t *rwlock)
++{
++	rt_read_lock(rwlock);
++
++	return 0;
++}
++EXPORT_SYMBOL(rt_read_lock_irqsave);
++
++void __rt_rwlock_init(rwlock_t *rwlock, char *name, struct lock_class_key *key)
++{
++#ifdef CONFIG_DEBUG_LOCK_ALLOC
++	/*
++	 * Make sure we are not reinitializing a held lock:
++	 */
++	debug_check_no_locks_freed((void *)rwlock, sizeof(*rwlock));
++	lockdep_init_map(&rwlock->dep_map, name, key, 0);
++#endif
++	rwlock->lock.save_state = 1;
++	rwlock->read_depth = 0;
++}
++EXPORT_SYMBOL(__rt_rwlock_init);
++
++/*
++ * rw_semaphores
++ */
++
++void  rt_up_write(struct rw_semaphore *rwsem)
++{
++	rwsem_release(&rwsem->dep_map, 1, _RET_IP_);
++	rt_mutex_unlock(&rwsem->lock);
++}
++EXPORT_SYMBOL(rt_up_write);
++
++void __rt_up_read(struct rw_semaphore *rwsem)
++{
++	if (--rwsem->read_depth == 0)
++		rt_mutex_unlock(&rwsem->lock);
++}
++
++void  rt_up_read(struct rw_semaphore *rwsem)
++{
++	rwsem_release(&rwsem->dep_map, 1, _RET_IP_);
++	__rt_up_read(rwsem);
++}
++EXPORT_SYMBOL(rt_up_read);
++
++/*
++ * downgrade a write lock into a read lock
++ * - just wake up any readers at the front of the queue
++ */
++void  rt_downgrade_write(struct rw_semaphore *rwsem)
++{
++	BUG_ON(rt_mutex_owner(&rwsem->lock) != current);
++	rwsem->read_depth = 1;
++}
++EXPORT_SYMBOL(rt_downgrade_write);
++
++int  rt_down_write_trylock(struct rw_semaphore *rwsem)
++{
++	int ret = rt_mutex_trylock(&rwsem->lock);
++
++	if (ret)
++		rwsem_acquire(&rwsem->dep_map, 0, 1, _RET_IP_);
++	return ret;
++}
++EXPORT_SYMBOL(rt_down_write_trylock);
++
++void  rt_down_write(struct rw_semaphore *rwsem)
++{
++	rwsem_acquire(&rwsem->dep_map, 0, 0, _RET_IP_);
++	rt_mutex_lock(&rwsem->lock);
++}
++EXPORT_SYMBOL(rt_down_write);
++
++void  rt_down_write_nested(struct rw_semaphore *rwsem, int subclass)
++{
++	rwsem_acquire(&rwsem->dep_map, subclass, 0, _RET_IP_);
++	rt_mutex_lock(&rwsem->lock);
++}
++EXPORT_SYMBOL(rt_down_write_nested);
++
++void rt_down_write_nested_lock(struct rw_semaphore *rwsem,
++			       struct lockdep_map *nest)
++{
++	rwsem_acquire_nest(&rwsem->dep_map, 0, 0, nest, _RET_IP_);
++	rt_mutex_lock(&rwsem->lock);
++}
++EXPORT_SYMBOL(rt_down_write_nested_lock);
++
++int rt__down_read_trylock(struct rw_semaphore *rwsem)
++{
++	struct rt_mutex *lock = &rwsem->lock;
++	int ret = 1;
++
++	/*
++	 * recursive read locks succeed when current owns the rwsem,
++	 * but not when read_depth == 0 which means that the rwsem is
++	 * write locked.
++	 */
++	if (rt_mutex_owner(lock) != current)
++		ret = rt_mutex_trylock(&rwsem->lock);
++	else if (!rwsem->read_depth)
++		ret = 0;
++
++	if (ret)
++		rwsem->read_depth++;
++	return ret;
++
++}
++
++int  rt_down_read_trylock(struct rw_semaphore *rwsem)
++{
++	int ret;
++
++	ret = rt__down_read_trylock(rwsem);
++	if (ret)
++		rwsem_acquire(&rwsem->dep_map, 0, 1, _RET_IP_);
++
++	return ret;
++}
++EXPORT_SYMBOL(rt_down_read_trylock);
++
++void rt__down_read(struct rw_semaphore *rwsem)
++{
++	struct rt_mutex *lock = &rwsem->lock;
++
++	if (rt_mutex_owner(lock) != current)
++		rt_mutex_lock(&rwsem->lock);
++	rwsem->read_depth++;
++}
++EXPORT_SYMBOL(rt__down_read);
++
++static void __rt_down_read(struct rw_semaphore *rwsem, int subclass)
++{
++	rwsem_acquire_read(&rwsem->dep_map, subclass, 0, _RET_IP_);
++	rt__down_read(rwsem);
++}
++
++void  rt_down_read(struct rw_semaphore *rwsem)
++{
++	__rt_down_read(rwsem, 0);
++}
++EXPORT_SYMBOL(rt_down_read);
++
++void  rt_down_read_nested(struct rw_semaphore *rwsem, int subclass)
++{
++	__rt_down_read(rwsem, subclass);
++}
++EXPORT_SYMBOL(rt_down_read_nested);
++
++void  __rt_rwsem_init(struct rw_semaphore *rwsem, const char *name,
++			      struct lock_class_key *key)
++{
++#ifdef CONFIG_DEBUG_LOCK_ALLOC
++	/*
++	 * Make sure we are not reinitializing a held lock:
++	 */
++	debug_check_no_locks_freed((void *)rwsem, sizeof(*rwsem));
++	lockdep_init_map(&rwsem->dep_map, name, key, 0);
++#endif
++	rwsem->read_depth = 0;
++	rwsem->lock.save_state = 0;
++}
++EXPORT_SYMBOL(__rt_rwsem_init);
++
++/**
++ * atomic_dec_and_mutex_lock - return holding mutex if we dec to 0
++ * @cnt: the atomic which we are to dec
++ * @lock: the mutex to return holding if we dec to 0
++ *
++ * return true and hold lock if we dec to 0, return false otherwise
++ */
++int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock)
++{
++	/* dec if we can't possibly hit 0 */
++	if (atomic_add_unless(cnt, -1, 1))
++		return 0;
++	/* we might hit 0, so take the lock */
++	mutex_lock(lock);
++	if (!atomic_dec_and_test(cnt)) {
++		/* when we actually did the dec, we didn't hit 0 */
++		mutex_unlock(lock);
++		return 0;
++	}
++	/* we hit 0, and we hold the lock */
++	return 1;
++}
++EXPORT_SYMBOL(atomic_dec_and_mutex_lock);
+diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
+index 3e746607abe5..fde5e54f1096 100644
+--- a/kernel/locking/rtmutex.c
++++ b/kernel/locking/rtmutex.c
+@@ -7,6 +7,11 @@
+  *  Copyright (C) 2005-2006 Timesys Corp., Thomas Gleixner <tglx@timesys.com>
+  *  Copyright (C) 2005 Kihon Technologies Inc., Steven Rostedt
+  *  Copyright (C) 2006 Esben Nielsen
++ *  Adaptive Spinlocks:
++ *  Copyright (C) 2008 Novell, Inc., Gregory Haskins, Sven Dietrich,
++ *				     and Peter Morreale,
++ * Adaptive Spinlocks simplification:
++ *  Copyright (C) 2008 Red Hat, Inc., Steven Rostedt <srostedt@redhat.com>
+  *
+  *  See Documentation/locking/rt-mutex-design.txt for details.
+  */
+@@ -16,6 +21,7 @@
+ #include <linux/sched/rt.h>
+ #include <linux/sched/deadline.h>
+ #include <linux/timer.h>
++#include <linux/ww_mutex.h>
+ 
+ #include "rtmutex_common.h"
+ 
+@@ -69,6 +75,12 @@ static void fixup_rt_mutex_waiters(struct rt_mutex *lock)
+ 		clear_rt_mutex_waiters(lock);
+ }
+ 
++static int rt_mutex_real_waiter(struct rt_mutex_waiter *waiter)
++{
++	return waiter && waiter != PI_WAKEUP_INPROGRESS &&
++		waiter != PI_REQUEUE_INPROGRESS;
++}
++
+ /*
+  * We can speed up the acquire/release, if there's no debugging state to be
+  * set up.
+@@ -350,6 +362,14 @@ static bool rt_mutex_cond_detect_deadlock(struct rt_mutex_waiter *waiter,
+ 	return debug_rt_mutex_detect_deadlock(waiter, chwalk);
+ }
+ 
++static void rt_mutex_wake_waiter(struct rt_mutex_waiter *waiter)
++{
++	if (waiter->savestate)
++		wake_up_lock_sleeper(waiter->task);
++	else
++		wake_up_process(waiter->task);
++}
++
+ /*
+  * Max number of times we'll walk the boosting chain:
+  */
+@@ -357,7 +377,8 @@ int max_lock_depth = 1024;
+ 
+ static inline struct rt_mutex *task_blocked_on_lock(struct task_struct *p)
+ {
+-	return p->pi_blocked_on ? p->pi_blocked_on->lock : NULL;
++	return rt_mutex_real_waiter(p->pi_blocked_on) ?
++		p->pi_blocked_on->lock : NULL;
+ }
+ 
+ /*
+@@ -493,7 +514,7 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
+ 	 * reached or the state of the chain has changed while we
+ 	 * dropped the locks.
+ 	 */
+-	if (!waiter)
++	if (!rt_mutex_real_waiter(waiter))
+ 		goto out_unlock_pi;
+ 
+ 	/*
+@@ -655,13 +676,16 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
+ 	 * follow here. This is the end of the chain we are walking.
+ 	 */
+ 	if (!rt_mutex_owner(lock)) {
++		struct rt_mutex_waiter *lock_top_waiter;
++
+ 		/*
+ 		 * If the requeue [7] above changed the top waiter,
+ 		 * then we need to wake the new top waiter up to try
+ 		 * to get the lock.
+ 		 */
+-		if (prerequeue_top_waiter != rt_mutex_top_waiter(lock))
+-			wake_up_process(rt_mutex_top_waiter(lock)->task);
++		lock_top_waiter = rt_mutex_top_waiter(lock);
++		if (prerequeue_top_waiter != lock_top_waiter)
++			rt_mutex_wake_waiter(lock_top_waiter);
+ 		raw_spin_unlock_irq(&lock->wait_lock);
+ 		return 0;
+ 	}
+@@ -754,6 +778,25 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
+ 	return ret;
+ }
+ 
++
++#define STEAL_NORMAL  0
++#define STEAL_LATERAL 1
++
++/*
++ * Note that RT tasks are excluded from lateral-steals to prevent the
++ * introduction of an unbounded latency
++ */
++static inline int lock_is_stealable(struct task_struct *task,
++				    struct task_struct *pendowner, int mode)
++{
++    if (mode == STEAL_NORMAL || rt_task(task)) {
++	    if (task->prio >= pendowner->prio)
++		    return 0;
++    } else if (task->prio > pendowner->prio)
++	    return 0;
++    return 1;
++}
++
+ /*
+  * Try to take an rt-mutex
+  *
+@@ -764,8 +807,9 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
+  * @waiter: The waiter that is queued to the lock's wait tree if the
+  *	    callsite called task_blocked_on_lock(), otherwise NULL
+  */
+-static int try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
+-				struct rt_mutex_waiter *waiter)
++static int __try_to_take_rt_mutex(struct rt_mutex *lock,
++				  struct task_struct *task,
++				  struct rt_mutex_waiter *waiter, int mode)
+ {
+ 	/*
+ 	 * Before testing whether we can acquire @lock, we set the
+@@ -802,8 +846,10 @@ static int try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
+ 		 * If waiter is not the highest priority waiter of
+ 		 * @lock, give up.
+ 		 */
+-		if (waiter != rt_mutex_top_waiter(lock))
++		if (waiter != rt_mutex_top_waiter(lock)) {
++			/* XXX lock_is_stealable() ? */
+ 			return 0;
++		}
+ 
+ 		/*
+ 		 * We can acquire the lock. Remove the waiter from the
+@@ -821,14 +867,10 @@ static int try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
+ 		 * not need to be dequeued.
+ 		 */
+ 		if (rt_mutex_has_waiters(lock)) {
+-			/*
+-			 * If @task->prio is greater than or equal to
+-			 * the top waiter priority (kernel view),
+-			 * @task lost.
+-			 */
+-			if (task->prio >= rt_mutex_top_waiter(lock)->prio)
+-				return 0;
++			struct task_struct *pown = rt_mutex_top_waiter(lock)->task;
+ 
++			if (task != pown && !lock_is_stealable(task, pown, mode))
++				return 0;
+ 			/*
+ 			 * The current top waiter stays enqueued. We
+ 			 * don't have to change anything in the lock
+@@ -877,6 +919,399 @@ static int try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
+ 	return 1;
+ }
+ 
++#ifdef CONFIG_PREEMPT_RT_FULL
++/*
++ * preemptible spin_lock functions:
++ */
++static inline void rt_spin_lock_fastlock(struct rt_mutex *lock,
++					 void  (*slowfn)(struct rt_mutex *lock,
++							 bool mg_off),
++					 bool do_mig_dis)
++{
++	might_sleep_no_state_check();
++
++	if (do_mig_dis)
++		migrate_disable();
++
++	if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current)))
++		rt_mutex_deadlock_account_lock(lock, current);
++	else
++		slowfn(lock, do_mig_dis);
++}
++
++static inline void rt_spin_lock_fastunlock(struct rt_mutex *lock,
++					   void  (*slowfn)(struct rt_mutex *lock))
++{
++	if (likely(rt_mutex_cmpxchg_release(lock, current, NULL)))
++		rt_mutex_deadlock_account_unlock(current);
++	else
++		slowfn(lock);
++}
++#ifdef CONFIG_SMP
++/*
++ * Note that owner is a speculative pointer and dereferencing relies
++ * on rcu_read_lock() and the check against the lock owner.
++ */
++static int adaptive_wait(struct rt_mutex *lock,
++			 struct task_struct *owner)
++{
++	int res = 0;
++
++	rcu_read_lock();
++	for (;;) {
++		if (owner != rt_mutex_owner(lock))
++			break;
++		/*
++		 * Ensure that owner->on_cpu is dereferenced _after_
++		 * checking the above to be valid.
++		 */
++		barrier();
++		if (!owner->on_cpu) {
++			res = 1;
++			break;
++		}
++		cpu_relax();
++	}
++	rcu_read_unlock();
++	return res;
++}
++#else
++static int adaptive_wait(struct rt_mutex *lock,
++			 struct task_struct *orig_owner)
++{
++	return 1;
++}
++#endif
++
++static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
++				   struct rt_mutex_waiter *waiter,
++				   struct task_struct *task,
++				   enum rtmutex_chainwalk chwalk);
++/*
++ * Slow path lock function spin_lock style: this variant is very
++ * careful not to miss any non-lock wakeups.
++ *
++ * We store the current state under p->pi_lock in p->saved_state and
++ * the try_to_wake_up() code handles this accordingly.
++ */
++static void  noinline __sched rt_spin_lock_slowlock(struct rt_mutex *lock,
++						    bool mg_off)
++{
++	struct task_struct *lock_owner, *self = current;
++	struct rt_mutex_waiter waiter, *top_waiter;
++	unsigned long flags;
++	int ret;
++
++	rt_mutex_init_waiter(&waiter, true);
++
++	raw_spin_lock_irqsave(&lock->wait_lock, flags);
++
++	if (__try_to_take_rt_mutex(lock, self, NULL, STEAL_LATERAL)) {
++		raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
++		return;
++	}
++
++	BUG_ON(rt_mutex_owner(lock) == self);
++
++	/*
++	 * We save whatever state the task is in and we'll restore it
++	 * after acquiring the lock taking real wakeups into account
++	 * as well. We are serialized via pi_lock against wakeups. See
++	 * try_to_wake_up().
++	 */
++	raw_spin_lock(&self->pi_lock);
++	self->saved_state = self->state;
++	__set_current_state_no_track(TASK_UNINTERRUPTIBLE);
++	raw_spin_unlock(&self->pi_lock);
++
++	ret = task_blocks_on_rt_mutex(lock, &waiter, self, RT_MUTEX_MIN_CHAINWALK);
++	BUG_ON(ret);
++
++	for (;;) {
++		/* Try to acquire the lock again. */
++		if (__try_to_take_rt_mutex(lock, self, &waiter, STEAL_LATERAL))
++			break;
++
++		top_waiter = rt_mutex_top_waiter(lock);
++		lock_owner = rt_mutex_owner(lock);
++
++		raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
++
++		debug_rt_mutex_print_deadlock(&waiter);
++
++		if (top_waiter != &waiter || adaptive_wait(lock, lock_owner)) {
++			if (mg_off)
++				migrate_enable();
++			schedule();
++			if (mg_off)
++				migrate_disable();
++		}
++
++		raw_spin_lock_irqsave(&lock->wait_lock, flags);
++
++		raw_spin_lock(&self->pi_lock);
++		__set_current_state_no_track(TASK_UNINTERRUPTIBLE);
++		raw_spin_unlock(&self->pi_lock);
++	}
++
++	/*
++	 * Restore the task state to current->saved_state. We set it
++	 * to the original state above and the try_to_wake_up() code
++	 * has possibly updated it when a real (non-rtmutex) wakeup
++	 * happened while we were blocked. Clear saved_state so
++	 * try_to_wakeup() does not get confused.
++	 */
++	raw_spin_lock(&self->pi_lock);
++	__set_current_state_no_track(self->saved_state);
++	self->saved_state = TASK_RUNNING;
++	raw_spin_unlock(&self->pi_lock);
++
++	/*
++	 * try_to_take_rt_mutex() sets the waiter bit
++	 * unconditionally. We might have to fix that up:
++	 */
++	fixup_rt_mutex_waiters(lock);
++
++	BUG_ON(rt_mutex_has_waiters(lock) && &waiter == rt_mutex_top_waiter(lock));
++	BUG_ON(!RB_EMPTY_NODE(&waiter.tree_entry));
++
++	raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
++
++	debug_rt_mutex_free_waiter(&waiter);
++}
++
++static void mark_wakeup_next_waiter(struct wake_q_head *wake_q,
++				    struct wake_q_head *wake_sleeper_q,
++				    struct rt_mutex *lock);
++/*
++ * Slow path to release a rt_mutex spin_lock style
++ */
++static void  noinline __sched rt_spin_lock_slowunlock(struct rt_mutex *lock)
++{
++	unsigned long flags;
++	WAKE_Q(wake_q);
++	WAKE_Q(wake_sleeper_q);
++
++	raw_spin_lock_irqsave(&lock->wait_lock, flags);
++
++	debug_rt_mutex_unlock(lock);
++
++	rt_mutex_deadlock_account_unlock(current);
++
++	if (!rt_mutex_has_waiters(lock)) {
++		lock->owner = NULL;
++		raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
++		return;
++	}
++
++	mark_wakeup_next_waiter(&wake_q, &wake_sleeper_q, lock);
++
++	raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
++	wake_up_q(&wake_q);
++	wake_up_q_sleeper(&wake_sleeper_q);
++
++	/* Undo pi boosting.when necessary */
++	rt_mutex_adjust_prio(current);
++}
++
++void __lockfunc rt_spin_lock__no_mg(spinlock_t *lock)
++{
++	rt_spin_lock_fastlock(&lock->lock, rt_spin_lock_slowlock, false);
++	spin_acquire(&lock->dep_map, 0, 0, _RET_IP_);
++}
++EXPORT_SYMBOL(rt_spin_lock__no_mg);
++
++void __lockfunc rt_spin_lock(spinlock_t *lock)
++{
++	rt_spin_lock_fastlock(&lock->lock, rt_spin_lock_slowlock, true);
++	spin_acquire(&lock->dep_map, 0, 0, _RET_IP_);
++}
++EXPORT_SYMBOL(rt_spin_lock);
++
++void __lockfunc __rt_spin_lock(struct rt_mutex *lock)
++{
++	rt_spin_lock_fastlock(lock, rt_spin_lock_slowlock, true);
++}
++EXPORT_SYMBOL(__rt_spin_lock);
++
++void __lockfunc __rt_spin_lock__no_mg(struct rt_mutex *lock)
++{
++	rt_spin_lock_fastlock(lock, rt_spin_lock_slowlock, false);
++}
++EXPORT_SYMBOL(__rt_spin_lock__no_mg);
++
++#ifdef CONFIG_DEBUG_LOCK_ALLOC
++void __lockfunc rt_spin_lock_nested(spinlock_t *lock, int subclass)
++{
++	spin_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
++	rt_spin_lock_fastlock(&lock->lock, rt_spin_lock_slowlock, true);
++}
++EXPORT_SYMBOL(rt_spin_lock_nested);
++#endif
++
++void __lockfunc rt_spin_unlock__no_mg(spinlock_t *lock)
++{
++	/* NOTE: we always pass in '1' for nested, for simplicity */
++	spin_release(&lock->dep_map, 1, _RET_IP_);
++	rt_spin_lock_fastunlock(&lock->lock, rt_spin_lock_slowunlock);
++}
++EXPORT_SYMBOL(rt_spin_unlock__no_mg);
++
++void __lockfunc rt_spin_unlock(spinlock_t *lock)
++{
++	/* NOTE: we always pass in '1' for nested, for simplicity */
++	spin_release(&lock->dep_map, 1, _RET_IP_);
++	rt_spin_lock_fastunlock(&lock->lock, rt_spin_lock_slowunlock);
++	migrate_enable();
++}
++EXPORT_SYMBOL(rt_spin_unlock);
++
++void __lockfunc __rt_spin_unlock(struct rt_mutex *lock)
++{
++	rt_spin_lock_fastunlock(lock, rt_spin_lock_slowunlock);
++}
++EXPORT_SYMBOL(__rt_spin_unlock);
++
++/*
++ * Wait for the lock to get unlocked: instead of polling for an unlock
++ * (like raw spinlocks do), we lock and unlock, to force the kernel to
++ * schedule if there's contention:
++ */
++void __lockfunc rt_spin_unlock_wait(spinlock_t *lock)
++{
++	spin_lock(lock);
++	spin_unlock(lock);
++}
++EXPORT_SYMBOL(rt_spin_unlock_wait);
++
++int __lockfunc __rt_spin_trylock(struct rt_mutex *lock)
++{
++	return rt_mutex_trylock(lock);
++}
++
++int __lockfunc rt_spin_trylock__no_mg(spinlock_t *lock)
++{
++	int ret;
++
++	ret = rt_mutex_trylock(&lock->lock);
++	if (ret)
++		spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
++	return ret;
++}
++EXPORT_SYMBOL(rt_spin_trylock__no_mg);
++
++int __lockfunc rt_spin_trylock(spinlock_t *lock)
++{
++	int ret;
++
++	migrate_disable();
++	ret = rt_mutex_trylock(&lock->lock);
++	if (ret)
++		spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
++	else
++		migrate_enable();
++	return ret;
++}
++EXPORT_SYMBOL(rt_spin_trylock);
++
++int __lockfunc rt_spin_trylock_bh(spinlock_t *lock)
++{
++	int ret;
++
++	local_bh_disable();
++	ret = rt_mutex_trylock(&lock->lock);
++	if (ret) {
++		migrate_disable();
++		spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
++	} else
++		local_bh_enable();
++	return ret;
++}
++EXPORT_SYMBOL(rt_spin_trylock_bh);
++
++int __lockfunc rt_spin_trylock_irqsave(spinlock_t *lock, unsigned long *flags)
++{
++	int ret;
++
++	*flags = 0;
++	ret = rt_mutex_trylock(&lock->lock);
++	if (ret) {
++		migrate_disable();
++		spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
++	}
++	return ret;
++}
++EXPORT_SYMBOL(rt_spin_trylock_irqsave);
++
++int atomic_dec_and_spin_lock(atomic_t *atomic, spinlock_t *lock)
++{
++	/* Subtract 1 from counter unless that drops it to 0 (ie. it was 1) */
++	if (atomic_add_unless(atomic, -1, 1))
++		return 0;
++	rt_spin_lock(lock);
++	if (atomic_dec_and_test(atomic))
++		return 1;
++	rt_spin_unlock(lock);
++	return 0;
++}
++EXPORT_SYMBOL(atomic_dec_and_spin_lock);
++
++	void
++__rt_spin_lock_init(spinlock_t *lock, char *name, struct lock_class_key *key)
++{
++#ifdef CONFIG_DEBUG_LOCK_ALLOC
++	/*
++	 * Make sure we are not reinitializing a held lock:
++	 */
++	debug_check_no_locks_freed((void *)lock, sizeof(*lock));
++	lockdep_init_map(&lock->dep_map, name, key, 0);
++#endif
++}
++EXPORT_SYMBOL(__rt_spin_lock_init);
++
++#endif /* PREEMPT_RT_FULL */
++
++#ifdef CONFIG_PREEMPT_RT_FULL
++	static inline int __sched
++__mutex_lock_check_stamp(struct rt_mutex *lock, struct ww_acquire_ctx *ctx)
++{
++	struct ww_mutex *ww = container_of(lock, struct ww_mutex, base.lock);
++	struct ww_acquire_ctx *hold_ctx = ACCESS_ONCE(ww->ctx);
++
++	if (!hold_ctx)
++		return 0;
++
++	if (unlikely(ctx == hold_ctx))
++		return -EALREADY;
++
++	if (ctx->stamp - hold_ctx->stamp <= LONG_MAX &&
++	    (ctx->stamp != hold_ctx->stamp || ctx > hold_ctx)) {
++#ifdef CONFIG_DEBUG_MUTEXES
++		DEBUG_LOCKS_WARN_ON(ctx->contending_lock);
++		ctx->contending_lock = ww;
++#endif
++		return -EDEADLK;
++	}
++
++	return 0;
++}
++#else
++	static inline int __sched
++__mutex_lock_check_stamp(struct rt_mutex *lock, struct ww_acquire_ctx *ctx)
++{
++	BUG();
++	return 0;
++}
++
++#endif
++
++static inline int
++try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
++		     struct rt_mutex_waiter *waiter)
++{
++	return __try_to_take_rt_mutex(lock, task, waiter, STEAL_NORMAL);
++}
++
+ /*
+  * Task blocks on lock.
+  *
+@@ -907,6 +1342,23 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
+ 		return -EDEADLK;
+ 
+ 	raw_spin_lock(&task->pi_lock);
++
++	/*
++	 * In the case of futex requeue PI, this will be a proxy
++	 * lock. The task will wake unaware that it is enqueueed on
++	 * this lock. Avoid blocking on two locks and corrupting
++	 * pi_blocked_on via the PI_WAKEUP_INPROGRESS
++	 * flag. futex_wait_requeue_pi() sets this when it wakes up
++	 * before requeue (due to a signal or timeout). Do not enqueue
++	 * the task if PI_WAKEUP_INPROGRESS is set.
++	 */
++	if (task != current && task->pi_blocked_on == PI_WAKEUP_INPROGRESS) {
++		raw_spin_unlock(&task->pi_lock);
++		return -EAGAIN;
++	}
++
++	BUG_ON(rt_mutex_real_waiter(task->pi_blocked_on));
++
+ 	__rt_mutex_adjust_prio(task);
+ 	waiter->task = task;
+ 	waiter->lock = lock;
+@@ -930,7 +1382,7 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
+ 		rt_mutex_enqueue_pi(owner, waiter);
+ 
+ 		__rt_mutex_adjust_prio(owner);
+-		if (owner->pi_blocked_on)
++		if (rt_mutex_real_waiter(owner->pi_blocked_on))
+ 			chain_walk = 1;
+ 	} else if (rt_mutex_cond_detect_deadlock(waiter, chwalk)) {
+ 		chain_walk = 1;
+@@ -972,6 +1424,7 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
+  * Called with lock->wait_lock held and interrupts disabled.
+  */
+ static void mark_wakeup_next_waiter(struct wake_q_head *wake_q,
++				    struct wake_q_head *wake_sleeper_q,
+ 				    struct rt_mutex *lock)
+ {
+ 	struct rt_mutex_waiter *waiter;
+@@ -1000,7 +1453,10 @@ static void mark_wakeup_next_waiter(struct wake_q_head *wake_q,
+ 
+ 	raw_spin_unlock(&current->pi_lock);
+ 
+-	wake_q_add(wake_q, waiter->task);
++	if (waiter->savestate)
++		wake_q_add(wake_sleeper_q, waiter->task);
++	else
++		wake_q_add(wake_q, waiter->task);
+ }
+ 
+ /*
+@@ -1014,7 +1470,7 @@ static void remove_waiter(struct rt_mutex *lock,
+ {
+ 	bool is_top_waiter = (waiter == rt_mutex_top_waiter(lock));
+ 	struct task_struct *owner = rt_mutex_owner(lock);
+-	struct rt_mutex *next_lock;
++	struct rt_mutex *next_lock = NULL;
+ 
+ 	raw_spin_lock(&current->pi_lock);
+ 	rt_mutex_dequeue(lock, waiter);
+@@ -1038,7 +1494,8 @@ static void remove_waiter(struct rt_mutex *lock,
+ 	__rt_mutex_adjust_prio(owner);
+ 
+ 	/* Store the lock on which owner is blocked or NULL */
+-	next_lock = task_blocked_on_lock(owner);
++	if (rt_mutex_real_waiter(owner->pi_blocked_on))
++		next_lock = task_blocked_on_lock(owner);
+ 
+ 	raw_spin_unlock(&owner->pi_lock);
+ 
+@@ -1074,17 +1531,17 @@ void rt_mutex_adjust_pi(struct task_struct *task)
+ 	raw_spin_lock_irqsave(&task->pi_lock, flags);
+ 
+ 	waiter = task->pi_blocked_on;
+-	if (!waiter || (waiter->prio == task->prio &&
++	if (!rt_mutex_real_waiter(waiter) || (waiter->prio == task->prio &&
+ 			!dl_prio(task->prio))) {
+ 		raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+ 		return;
+ 	}
+ 	next_lock = waiter->lock;
+-	raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+ 
+ 	/* gets dropped in rt_mutex_adjust_prio_chain()! */
+ 	get_task_struct(task);
+ 
++	raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+ 	rt_mutex_adjust_prio_chain(task, RT_MUTEX_MIN_CHAINWALK, NULL,
+ 				   next_lock, NULL, task);
+ }
+@@ -1102,7 +1559,8 @@ void rt_mutex_adjust_pi(struct task_struct *task)
+ static int __sched
+ __rt_mutex_slowlock(struct rt_mutex *lock, int state,
+ 		    struct hrtimer_sleeper *timeout,
+-		    struct rt_mutex_waiter *waiter)
++		    struct rt_mutex_waiter *waiter,
++		    struct ww_acquire_ctx *ww_ctx)
+ {
+ 	int ret = 0;
+ 
+@@ -1125,6 +1583,12 @@ __rt_mutex_slowlock(struct rt_mutex *lock, int state,
+ 				break;
+ 		}
+ 
++		if (ww_ctx && ww_ctx->acquired > 0) {
++			ret = __mutex_lock_check_stamp(lock, ww_ctx);
++			if (ret)
++				break;
++		}
++
+ 		raw_spin_unlock_irq(&lock->wait_lock);
+ 
+ 		debug_rt_mutex_print_deadlock(waiter);
+@@ -1159,21 +1623,96 @@ static void rt_mutex_handle_deadlock(int res, int detect_deadlock,
+ 	}
+ }
+ 
++static __always_inline void ww_mutex_lock_acquired(struct ww_mutex *ww,
++						   struct ww_acquire_ctx *ww_ctx)
++{
++#ifdef CONFIG_DEBUG_MUTEXES
++	/*
++	 * If this WARN_ON triggers, you used ww_mutex_lock to acquire,
++	 * but released with a normal mutex_unlock in this call.
++	 *
++	 * This should never happen, always use ww_mutex_unlock.
++	 */
++	DEBUG_LOCKS_WARN_ON(ww->ctx);
++
++	/*
++	 * Not quite done after calling ww_acquire_done() ?
++	 */
++	DEBUG_LOCKS_WARN_ON(ww_ctx->done_acquire);
++
++	if (ww_ctx->contending_lock) {
++		/*
++		 * After -EDEADLK you tried to
++		 * acquire a different ww_mutex? Bad!
++		 */
++		DEBUG_LOCKS_WARN_ON(ww_ctx->contending_lock != ww);
++
++		/*
++		 * You called ww_mutex_lock after receiving -EDEADLK,
++		 * but 'forgot' to unlock everything else first?
++		 */
++		DEBUG_LOCKS_WARN_ON(ww_ctx->acquired > 0);
++		ww_ctx->contending_lock = NULL;
++	}
++
++	/*
++	 * Naughty, using a different class will lead to undefined behavior!
++	 */
++	DEBUG_LOCKS_WARN_ON(ww_ctx->ww_class != ww->ww_class);
++#endif
++	ww_ctx->acquired++;
++}
++
++#ifdef CONFIG_PREEMPT_RT_FULL
++static void ww_mutex_account_lock(struct rt_mutex *lock,
++				  struct ww_acquire_ctx *ww_ctx)
++{
++	struct ww_mutex *ww = container_of(lock, struct ww_mutex, base.lock);
++	struct rt_mutex_waiter *waiter, *n;
++
++	/*
++	 * This branch gets optimized out for the common case,
++	 * and is only important for ww_mutex_lock.
++	 */
++	ww_mutex_lock_acquired(ww, ww_ctx);
++	ww->ctx = ww_ctx;
++
++	/*
++	 * Give any possible sleeping processes the chance to wake up,
++	 * so they can recheck if they have to back off.
++	 */
++	rbtree_postorder_for_each_entry_safe(waiter, n, &lock->waiters,
++					     tree_entry) {
++		/* XXX debug rt mutex waiter wakeup */
++
++		BUG_ON(waiter->lock != lock);
++		rt_mutex_wake_waiter(waiter);
++	}
++}
++
++#else
++
++static void ww_mutex_account_lock(struct rt_mutex *lock,
++				  struct ww_acquire_ctx *ww_ctx)
++{
++	BUG();
++}
++#endif
++
+ /*
+  * Slow path lock function:
+  */
+ static int __sched
+ rt_mutex_slowlock(struct rt_mutex *lock, int state,
+ 		  struct hrtimer_sleeper *timeout,
+-		  enum rtmutex_chainwalk chwalk)
++		  enum rtmutex_chainwalk chwalk,
++		  struct ww_acquire_ctx *ww_ctx)
+ {
+ 	struct rt_mutex_waiter waiter;
+ 	unsigned long flags;
+ 	int ret = 0;
+ 
+-	debug_rt_mutex_init_waiter(&waiter);
+-	RB_CLEAR_NODE(&waiter.pi_tree_entry);
+-	RB_CLEAR_NODE(&waiter.tree_entry);
++	rt_mutex_init_waiter(&waiter, false);
+ 
+ 	/*
+ 	 * Technically we could use raw_spin_[un]lock_irq() here, but this can
+@@ -1187,6 +1726,8 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state,
+ 
+ 	/* Try to acquire the lock again: */
+ 	if (try_to_take_rt_mutex(lock, current, NULL)) {
++		if (ww_ctx)
++			ww_mutex_account_lock(lock, ww_ctx);
+ 		raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
+ 		return 0;
+ 	}
+@@ -1201,13 +1742,23 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state,
+ 
+ 	if (likely(!ret))
+ 		/* sleep on the mutex */
+-		ret = __rt_mutex_slowlock(lock, state, timeout, &waiter);
++		ret = __rt_mutex_slowlock(lock, state, timeout, &waiter,
++					  ww_ctx);
++	else if (ww_ctx) {
++		/* ww_mutex received EDEADLK, let it become EALREADY */
++		ret = __mutex_lock_check_stamp(lock, ww_ctx);
++		BUG_ON(!ret);
++	}
+ 
+ 	if (unlikely(ret)) {
+ 		__set_current_state(TASK_RUNNING);
+ 		if (rt_mutex_has_waiters(lock))
+ 			remove_waiter(lock, &waiter);
+-		rt_mutex_handle_deadlock(ret, chwalk, &waiter);
++		/* ww_mutex want to report EDEADLK/EALREADY, let them */
++		if (!ww_ctx)
++			rt_mutex_handle_deadlock(ret, chwalk, &waiter);
++	} else if (ww_ctx) {
++		ww_mutex_account_lock(lock, ww_ctx);
+ 	}
+ 
+ 	/*
+@@ -1267,7 +1818,8 @@ static inline int rt_mutex_slowtrylock(struct rt_mutex *lock)
+  * Return whether the current task needs to undo a potential priority boosting.
+  */
+ static bool __sched rt_mutex_slowunlock(struct rt_mutex *lock,
+-					struct wake_q_head *wake_q)
++					struct wake_q_head *wake_q,
++					struct wake_q_head *wake_sleeper_q)
+ {
+ 	unsigned long flags;
+ 
+@@ -1323,7 +1875,7 @@ static bool __sched rt_mutex_slowunlock(struct rt_mutex *lock,
+ 	 *
+ 	 * Queue the next waiter for wakeup once we release the wait_lock.
+ 	 */
+-	mark_wakeup_next_waiter(wake_q, lock);
++	mark_wakeup_next_waiter(wake_q, wake_sleeper_q, lock);
+ 
+ 	raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
+ 
+@@ -1339,31 +1891,36 @@ static bool __sched rt_mutex_slowunlock(struct rt_mutex *lock,
+  */
+ static inline int
+ rt_mutex_fastlock(struct rt_mutex *lock, int state,
++		  struct ww_acquire_ctx *ww_ctx,
+ 		  int (*slowfn)(struct rt_mutex *lock, int state,
+ 				struct hrtimer_sleeper *timeout,
+-				enum rtmutex_chainwalk chwalk))
++				enum rtmutex_chainwalk chwalk,
++				struct ww_acquire_ctx *ww_ctx))
+ {
+ 	if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current))) {
+ 		rt_mutex_deadlock_account_lock(lock, current);
+ 		return 0;
+ 	} else
+-		return slowfn(lock, state, NULL, RT_MUTEX_MIN_CHAINWALK);
++		return slowfn(lock, state, NULL, RT_MUTEX_MIN_CHAINWALK,
++			      ww_ctx);
+ }
+ 
+ static inline int
+ rt_mutex_timed_fastlock(struct rt_mutex *lock, int state,
+ 			struct hrtimer_sleeper *timeout,
+ 			enum rtmutex_chainwalk chwalk,
++			struct ww_acquire_ctx *ww_ctx,
+ 			int (*slowfn)(struct rt_mutex *lock, int state,
+ 				      struct hrtimer_sleeper *timeout,
+-				      enum rtmutex_chainwalk chwalk))
++				      enum rtmutex_chainwalk chwalk,
++				      struct ww_acquire_ctx *ww_ctx))
+ {
+ 	if (chwalk == RT_MUTEX_MIN_CHAINWALK &&
+ 	    likely(rt_mutex_cmpxchg_acquire(lock, NULL, current))) {
+ 		rt_mutex_deadlock_account_lock(lock, current);
+ 		return 0;
+ 	} else
+-		return slowfn(lock, state, timeout, chwalk);
++		return slowfn(lock, state, timeout, chwalk, ww_ctx);
+ }
+ 
+ static inline int
+@@ -1380,17 +1937,20 @@ rt_mutex_fasttrylock(struct rt_mutex *lock,
+ static inline void
+ rt_mutex_fastunlock(struct rt_mutex *lock,
+ 		    bool (*slowfn)(struct rt_mutex *lock,
+-				   struct wake_q_head *wqh))
++				   struct wake_q_head *wqh,
++				   struct wake_q_head *wq_sleeper))
+ {
+ 	WAKE_Q(wake_q);
++	WAKE_Q(wake_sleeper_q);
+ 
+ 	if (likely(rt_mutex_cmpxchg_release(lock, current, NULL))) {
+ 		rt_mutex_deadlock_account_unlock(current);
+ 
+ 	} else {
+-		bool deboost = slowfn(lock, &wake_q);
++		bool deboost = slowfn(lock, &wake_q, &wake_sleeper_q);
+ 
+ 		wake_up_q(&wake_q);
++		wake_up_q_sleeper(&wake_sleeper_q);
+ 
+ 		/* Undo pi boosting if necessary: */
+ 		if (deboost)
+@@ -1407,7 +1967,7 @@ void __sched rt_mutex_lock(struct rt_mutex *lock)
+ {
+ 	might_sleep();
+ 
+-	rt_mutex_fastlock(lock, TASK_UNINTERRUPTIBLE, rt_mutex_slowlock);
++	rt_mutex_fastlock(lock, TASK_UNINTERRUPTIBLE, NULL, rt_mutex_slowlock);
+ }
+ EXPORT_SYMBOL_GPL(rt_mutex_lock);
+ 
+@@ -1424,7 +1984,7 @@ int __sched rt_mutex_lock_interruptible(struct rt_mutex *lock)
+ {
+ 	might_sleep();
+ 
+-	return rt_mutex_fastlock(lock, TASK_INTERRUPTIBLE, rt_mutex_slowlock);
++	return rt_mutex_fastlock(lock, TASK_INTERRUPTIBLE, NULL, rt_mutex_slowlock);
+ }
+ EXPORT_SYMBOL_GPL(rt_mutex_lock_interruptible);
+ 
+@@ -1437,11 +1997,30 @@ int rt_mutex_timed_futex_lock(struct rt_mutex *lock,
+ 	might_sleep();
+ 
+ 	return rt_mutex_timed_fastlock(lock, TASK_INTERRUPTIBLE, timeout,
+-				       RT_MUTEX_FULL_CHAINWALK,
++				       RT_MUTEX_FULL_CHAINWALK, NULL,
+ 				       rt_mutex_slowlock);
+ }
+ 
+ /**
++ * rt_mutex_lock_killable - lock a rt_mutex killable
++ *
++ * @lock:              the rt_mutex to be locked
++ * @detect_deadlock:   deadlock detection on/off
++ *
++ * Returns:
++ *  0          on success
++ * -EINTR      when interrupted by a signal
++ * -EDEADLK    when the lock would deadlock (when deadlock detection is on)
++ */
++int __sched rt_mutex_lock_killable(struct rt_mutex *lock)
++{
++	might_sleep();
++
++	return rt_mutex_fastlock(lock, TASK_KILLABLE, NULL, rt_mutex_slowlock);
++}
++EXPORT_SYMBOL_GPL(rt_mutex_lock_killable);
++
++/**
+  * rt_mutex_timed_lock - lock a rt_mutex interruptible
+  *			the timeout structure is provided
+  *			by the caller
+@@ -1461,6 +2040,7 @@ rt_mutex_timed_lock(struct rt_mutex *lock, struct hrtimer_sleeper *timeout)
+ 
+ 	return rt_mutex_timed_fastlock(lock, TASK_INTERRUPTIBLE, timeout,
+ 				       RT_MUTEX_MIN_CHAINWALK,
++				       NULL,
+ 				       rt_mutex_slowlock);
+ }
+ EXPORT_SYMBOL_GPL(rt_mutex_timed_lock);
+@@ -1478,7 +2058,11 @@ EXPORT_SYMBOL_GPL(rt_mutex_timed_lock);
+  */
+ int __sched rt_mutex_trylock(struct rt_mutex *lock)
+ {
++#ifdef CONFIG_PREEMPT_RT_FULL
++	if (WARN_ON_ONCE(in_irq() || in_nmi()))
++#else
+ 	if (WARN_ON(in_irq() || in_nmi() || in_serving_softirq()))
++#endif
+ 		return 0;
+ 
+ 	return rt_mutex_fasttrylock(lock, rt_mutex_slowtrylock);
+@@ -1504,13 +2088,14 @@ EXPORT_SYMBOL_GPL(rt_mutex_unlock);
+  * required or not.
+  */
+ bool __sched rt_mutex_futex_unlock(struct rt_mutex *lock,
+-				   struct wake_q_head *wqh)
++				   struct wake_q_head *wqh,
++				   struct wake_q_head *wq_sleeper)
+ {
+ 	if (likely(rt_mutex_cmpxchg_release(lock, current, NULL))) {
+ 		rt_mutex_deadlock_account_unlock(current);
+ 		return false;
+ 	}
+-	return rt_mutex_slowunlock(lock, wqh);
++	return rt_mutex_slowunlock(lock, wqh, wq_sleeper);
+ }
+ 
+ /**
+@@ -1543,13 +2128,12 @@ EXPORT_SYMBOL_GPL(rt_mutex_destroy);
+ void __rt_mutex_init(struct rt_mutex *lock, const char *name)
+ {
+ 	lock->owner = NULL;
+-	raw_spin_lock_init(&lock->wait_lock);
+ 	lock->waiters = RB_ROOT;
+ 	lock->waiters_leftmost = NULL;
+ 
+ 	debug_rt_mutex_init(lock, name);
+ }
+-EXPORT_SYMBOL_GPL(__rt_mutex_init);
++EXPORT_SYMBOL(__rt_mutex_init);
+ 
+ /**
+  * rt_mutex_init_proxy_locked - initialize and lock a rt_mutex on behalf of a
+@@ -1564,7 +2148,7 @@ EXPORT_SYMBOL_GPL(__rt_mutex_init);
+ void rt_mutex_init_proxy_locked(struct rt_mutex *lock,
+ 				struct task_struct *proxy_owner)
+ {
+-	__rt_mutex_init(lock, NULL);
++	rt_mutex_init(lock);
+ 	debug_rt_mutex_proxy_lock(lock, proxy_owner);
+ 	rt_mutex_set_owner(lock, proxy_owner);
+ 	rt_mutex_deadlock_account_lock(lock, proxy_owner);
+@@ -1612,6 +2196,35 @@ int rt_mutex_start_proxy_lock(struct rt_mutex *lock,
+ 		return 1;
+ 	}
+ 
++#ifdef CONFIG_PREEMPT_RT_FULL
++	/*
++	 * In PREEMPT_RT there's an added race.
++	 * If the task, that we are about to requeue, times out,
++	 * it can set the PI_WAKEUP_INPROGRESS. This tells the requeue
++	 * to skip this task. But right after the task sets
++	 * its pi_blocked_on to PI_WAKEUP_INPROGRESS it can then
++	 * block on the spin_lock(&hb->lock), which in RT is an rtmutex.
++	 * This will replace the PI_WAKEUP_INPROGRESS with the actual
++	 * lock that it blocks on. We *must not* place this task
++	 * on this proxy lock in that case.
++	 *
++	 * To prevent this race, we first take the task's pi_lock
++	 * and check if it has updated its pi_blocked_on. If it has,
++	 * we assume that it woke up and we return -EAGAIN.
++	 * Otherwise, we set the task's pi_blocked_on to
++	 * PI_REQUEUE_INPROGRESS, so that if the task is waking up
++	 * it will know that we are in the process of requeuing it.
++	 */
++	raw_spin_lock(&task->pi_lock);
++	if (task->pi_blocked_on) {
++		raw_spin_unlock(&task->pi_lock);
++		raw_spin_unlock_irq(&lock->wait_lock);
++		return -EAGAIN;
++	}
++	task->pi_blocked_on = PI_REQUEUE_INPROGRESS;
++	raw_spin_unlock(&task->pi_lock);
++#endif
++
+ 	/* We enforce deadlock detection for futexes */
+ 	ret = task_blocks_on_rt_mutex(lock, waiter, task,
+ 				      RT_MUTEX_FULL_CHAINWALK);
+@@ -1626,7 +2239,7 @@ int rt_mutex_start_proxy_lock(struct rt_mutex *lock,
+ 		ret = 0;
+ 	}
+ 
+-	if (unlikely(ret))
++	if (ret && rt_mutex_has_waiters(lock))
+ 		remove_waiter(lock, waiter);
+ 
+ 	raw_spin_unlock_irq(&lock->wait_lock);
+@@ -1682,7 +2295,7 @@ int rt_mutex_finish_proxy_lock(struct rt_mutex *lock,
+ 	set_current_state(TASK_INTERRUPTIBLE);
+ 
+ 	/* sleep on the mutex */
+-	ret = __rt_mutex_slowlock(lock, TASK_INTERRUPTIBLE, to, waiter);
++	ret = __rt_mutex_slowlock(lock, TASK_INTERRUPTIBLE, to, waiter, NULL);
+ 
+ 	if (unlikely(ret))
+ 		remove_waiter(lock, waiter);
+@@ -1697,3 +2310,89 @@ int rt_mutex_finish_proxy_lock(struct rt_mutex *lock,
+ 
+ 	return ret;
+ }
++
++static inline int
++ww_mutex_deadlock_injection(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
++{
++#ifdef CONFIG_DEBUG_WW_MUTEX_SLOWPATH
++	unsigned tmp;
++
++	if (ctx->deadlock_inject_countdown-- == 0) {
++		tmp = ctx->deadlock_inject_interval;
++		if (tmp > UINT_MAX/4)
++			tmp = UINT_MAX;
++		else
++			tmp = tmp*2 + tmp + tmp/2;
++
++		ctx->deadlock_inject_interval = tmp;
++		ctx->deadlock_inject_countdown = tmp;
++		ctx->contending_lock = lock;
++
++		ww_mutex_unlock(lock);
++
++		return -EDEADLK;
++	}
++#endif
++
++	return 0;
++}
++
++#ifdef CONFIG_PREEMPT_RT_FULL
++int __sched
++__ww_mutex_lock_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ww_ctx)
++{
++	int ret;
++
++	might_sleep();
++
++	mutex_acquire_nest(&lock->base.dep_map, 0, 0, &ww_ctx->dep_map, _RET_IP_);
++	ret = rt_mutex_slowlock(&lock->base.lock, TASK_INTERRUPTIBLE, NULL, 0, ww_ctx);
++	if (ret)
++		mutex_release(&lock->base.dep_map, 1, _RET_IP_);
++	else if (!ret && ww_ctx->acquired > 1)
++		return ww_mutex_deadlock_injection(lock, ww_ctx);
++
++	return ret;
++}
++EXPORT_SYMBOL_GPL(__ww_mutex_lock_interruptible);
++
++int __sched
++__ww_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ww_ctx)
++{
++	int ret;
++
++	might_sleep();
++
++	mutex_acquire_nest(&lock->base.dep_map, 0, 0, &ww_ctx->dep_map, _RET_IP_);
++	ret = rt_mutex_slowlock(&lock->base.lock, TASK_UNINTERRUPTIBLE, NULL, 0, ww_ctx);
++	if (ret)
++		mutex_release(&lock->base.dep_map, 1, _RET_IP_);
++	else if (!ret && ww_ctx->acquired > 1)
++		return ww_mutex_deadlock_injection(lock, ww_ctx);
++
++	return ret;
++}
++EXPORT_SYMBOL_GPL(__ww_mutex_lock);
++
++void __sched ww_mutex_unlock(struct ww_mutex *lock)
++{
++	int nest = !!lock->ctx;
++
++	/*
++	 * The unlocking fastpath is the 0->1 transition from 'locked'
++	 * into 'unlocked' state:
++	 */
++	if (nest) {
++#ifdef CONFIG_DEBUG_MUTEXES
++		DEBUG_LOCKS_WARN_ON(!lock->ctx->acquired);
++#endif
++		if (lock->ctx->acquired > 0)
++			lock->ctx->acquired--;
++		lock->ctx = NULL;
++	}
++
++	mutex_release(&lock->base.dep_map, nest, _RET_IP_);
++	rt_mutex_unlock(&lock->base.lock);
++}
++EXPORT_SYMBOL(ww_mutex_unlock);
++#endif
+diff --git a/kernel/locking/rtmutex_common.h b/kernel/locking/rtmutex_common.h
+index 4f5f83c7d2d3..289f062f26cd 100644
+--- a/kernel/locking/rtmutex_common.h
++++ b/kernel/locking/rtmutex_common.h
+@@ -27,6 +27,7 @@ struct rt_mutex_waiter {
+ 	struct rb_node          pi_tree_entry;
+ 	struct task_struct	*task;
+ 	struct rt_mutex		*lock;
++	bool			savestate;
+ #ifdef CONFIG_DEBUG_RT_MUTEXES
+ 	unsigned long		ip;
+ 	struct pid		*deadlock_task_pid;
+@@ -97,6 +98,9 @@ enum rtmutex_chainwalk {
+ /*
+  * PI-futex support (proxy locking functions, etc.):
+  */
++#define PI_WAKEUP_INPROGRESS	((struct rt_mutex_waiter *) 1)
++#define PI_REQUEUE_INPROGRESS	((struct rt_mutex_waiter *) 2)
++
+ extern struct task_struct *rt_mutex_next_owner(struct rt_mutex *lock);
+ extern void rt_mutex_init_proxy_locked(struct rt_mutex *lock,
+ 				       struct task_struct *proxy_owner);
+@@ -110,7 +114,8 @@ extern int rt_mutex_finish_proxy_lock(struct rt_mutex *lock,
+ 				      struct rt_mutex_waiter *waiter);
+ extern int rt_mutex_timed_futex_lock(struct rt_mutex *l, struct hrtimer_sleeper *to);
+ extern bool rt_mutex_futex_unlock(struct rt_mutex *lock,
+-				  struct wake_q_head *wqh);
++				  struct wake_q_head *wqh,
++				  struct wake_q_head *wq_sleeper);
+ extern void rt_mutex_adjust_prio(struct task_struct *task);
+ 
+ #ifdef CONFIG_DEBUG_RT_MUTEXES
+@@ -119,4 +124,14 @@ extern void rt_mutex_adjust_prio(struct task_struct *task);
+ # include "rtmutex.h"
+ #endif
+ 
++static inline void
++rt_mutex_init_waiter(struct rt_mutex_waiter *waiter, bool savestate)
++{
++	debug_rt_mutex_init_waiter(waiter);
++	waiter->task = NULL;
++	waiter->savestate = savestate;
++	RB_CLEAR_NODE(&waiter->pi_tree_entry);
++	RB_CLEAR_NODE(&waiter->tree_entry);
++}
++
+ #endif
+diff --git a/kernel/locking/spinlock.c b/kernel/locking/spinlock.c
+index db3ccb1dd614..909779647bd1 100644
+--- a/kernel/locking/spinlock.c
++++ b/kernel/locking/spinlock.c
+@@ -124,8 +124,11 @@ void __lockfunc __raw_##op##_lock_bh(locktype##_t *lock)		\
+  *         __[spin|read|write]_lock_bh()
+  */
+ BUILD_LOCK_OPS(spin, raw_spinlock);
++
++#ifndef CONFIG_PREEMPT_RT_FULL
+ BUILD_LOCK_OPS(read, rwlock);
+ BUILD_LOCK_OPS(write, rwlock);
++#endif
+ 
+ #endif
+ 
+@@ -209,6 +212,8 @@ void __lockfunc _raw_spin_unlock_bh(raw_spinlock_t *lock)
+ EXPORT_SYMBOL(_raw_spin_unlock_bh);
+ #endif
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
++
+ #ifndef CONFIG_INLINE_READ_TRYLOCK
+ int __lockfunc _raw_read_trylock(rwlock_t *lock)
+ {
+@@ -353,6 +358,8 @@ void __lockfunc _raw_write_unlock_bh(rwlock_t *lock)
+ EXPORT_SYMBOL(_raw_write_unlock_bh);
+ #endif
+ 
++#endif /* !PREEMPT_RT_FULL */
++
+ #ifdef CONFIG_DEBUG_LOCK_ALLOC
+ 
+ void __lockfunc _raw_spin_lock_nested(raw_spinlock_t *lock, int subclass)
+diff --git a/kernel/locking/spinlock_debug.c b/kernel/locking/spinlock_debug.c
+index 0374a596cffa..94970338d518 100644
+--- a/kernel/locking/spinlock_debug.c
++++ b/kernel/locking/spinlock_debug.c
+@@ -31,6 +31,7 @@ void __raw_spin_lock_init(raw_spinlock_t *lock, const char *name,
+ 
+ EXPORT_SYMBOL(__raw_spin_lock_init);
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
+ void __rwlock_init(rwlock_t *lock, const char *name,
+ 		   struct lock_class_key *key)
+ {
+@@ -48,6 +49,7 @@ void __rwlock_init(rwlock_t *lock, const char *name,
+ }
+ 
+ EXPORT_SYMBOL(__rwlock_init);
++#endif
+ 
+ static void spin_dump(raw_spinlock_t *lock, const char *msg)
+ {
+@@ -159,6 +161,7 @@ void do_raw_spin_unlock(raw_spinlock_t *lock)
+ 	arch_spin_unlock(&lock->raw_lock);
+ }
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
+ static void rwlock_bug(rwlock_t *lock, const char *msg)
+ {
+ 	if (!debug_locks_off())
+@@ -300,3 +303,5 @@ void do_raw_write_unlock(rwlock_t *lock)
+ 	debug_write_unlock(lock);
+ 	arch_write_unlock(&lock->raw_lock);
+ }
++
++#endif
+diff --git a/kernel/panic.c b/kernel/panic.c
+index 535c96510a44..3373a70ac3f0 100644
+--- a/kernel/panic.c
++++ b/kernel/panic.c
+@@ -444,9 +444,11 @@ 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;
+diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
+index fca9254280ee..4e4063e7b5cc 100644
+--- a/kernel/power/hibernate.c
++++ b/kernel/power/hibernate.c
+@@ -285,6 +285,8 @@ static int create_image(int platform_mode)
+ 
+ 	local_irq_disable();
+ 
++	system_state = SYSTEM_SUSPEND;
++
+ 	error = syscore_suspend();
+ 	if (error) {
+ 		printk(KERN_ERR "PM: Some system devices failed to power down, "
+@@ -314,6 +316,7 @@ static int create_image(int platform_mode)
+ 	syscore_resume();
+ 
+  Enable_irqs:
++	system_state = SYSTEM_RUNNING;
+ 	local_irq_enable();
+ 
+  Enable_cpus:
+@@ -438,6 +441,7 @@ static int resume_target_kernel(bool platform_mode)
+ 		goto Enable_cpus;
+ 
+ 	local_irq_disable();
++	system_state = SYSTEM_SUSPEND;
+ 
+ 	error = syscore_suspend();
+ 	if (error)
+@@ -471,6 +475,7 @@ static int resume_target_kernel(bool platform_mode)
+ 	syscore_resume();
+ 
+  Enable_irqs:
++	system_state = SYSTEM_RUNNING;
+ 	local_irq_enable();
+ 
+  Enable_cpus:
+@@ -556,6 +561,7 @@ int hibernation_platform_enter(void)
+ 		goto Enable_cpus;
+ 
+ 	local_irq_disable();
++	system_state = SYSTEM_SUSPEND;
+ 	syscore_suspend();
+ 	if (pm_wakeup_pending()) {
+ 		error = -EAGAIN;
+@@ -568,6 +574,7 @@ int hibernation_platform_enter(void)
+ 
+  Power_up:
+ 	syscore_resume();
++	system_state = SYSTEM_RUNNING;
+ 	local_irq_enable();
+ 
+  Enable_cpus:
+@@ -642,6 +649,10 @@ static void power_down(void)
+ 		cpu_relax();
+ }
+ 
++#ifndef CONFIG_SUSPEND
++bool pm_in_action;
++#endif
++
+ /**
+  * hibernate - Carry out system hibernation, including saving the image.
+  */
+@@ -654,6 +665,8 @@ int hibernate(void)
+ 		return -EPERM;
+ 	}
+ 
++	pm_in_action = true;
++
+ 	lock_system_sleep();
+ 	/* The snapshot device should not be opened while we're running */
+ 	if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
+@@ -719,6 +732,7 @@ int hibernate(void)
+ 	atomic_inc(&snapshot_device_available);
+  Unlock:
+ 	unlock_system_sleep();
++	pm_in_action = false;
+ 	return error;
+ }
+ 
+diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
+index 5b70d64b871e..e25382cfb249 100644
+--- a/kernel/power/suspend.c
++++ b/kernel/power/suspend.c
+@@ -359,6 +359,8 @@ static int suspend_enter(suspend_state_t state, bool *wakeup)
+ 	arch_suspend_disable_irqs();
+ 	BUG_ON(!irqs_disabled());
+ 
++	system_state = SYSTEM_SUSPEND;
++
+ 	error = syscore_suspend();
+ 	if (!error) {
+ 		*wakeup = pm_wakeup_pending();
+@@ -375,6 +377,8 @@ static int suspend_enter(suspend_state_t state, bool *wakeup)
+ 		syscore_resume();
+ 	}
+ 
++	system_state = SYSTEM_RUNNING;
++
+ 	arch_suspend_enable_irqs();
+ 	BUG_ON(irqs_disabled());
+ 
+@@ -517,6 +521,8 @@ static int enter_state(suspend_state_t state)
+ 	return error;
+ }
+ 
++bool pm_in_action;
++
+ /**
+  * pm_suspend - Externally visible function for suspending the system.
+  * @state: System sleep state to enter.
+@@ -531,6 +537,8 @@ int pm_suspend(suspend_state_t state)
+ 	if (state <= PM_SUSPEND_ON || state >= PM_SUSPEND_MAX)
+ 		return -EINVAL;
+ 
++	pm_in_action = true;
++
+ 	error = enter_state(state);
+ 	if (error) {
+ 		suspend_stats.fail++;
+@@ -538,6 +546,7 @@ int pm_suspend(suspend_state_t state)
+ 	} else {
+ 		suspend_stats.success++;
+ 	}
++	pm_in_action = false;
+ 	return error;
+ }
+ EXPORT_SYMBOL(pm_suspend);
+diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
+index bfbf284e4218..ba5e3381a8cc 100644
+--- a/kernel/printk/printk.c
++++ b/kernel/printk/printk.c
+@@ -246,6 +246,65 @@ __packed __aligned(4)
+  */
+ static DEFINE_RAW_SPINLOCK(logbuf_lock);
+ 
++#ifdef CONFIG_EARLY_PRINTK
++struct console *early_console;
++
++static 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;
++}
++
++#ifdef CONFIG_PRINTK
++static int forced_early_printk(const char *fmt, va_list ap)
++{
++	if (!printk_killswitch)
++		return 0;
++	early_vprintk(fmt, ap);
++	return 1;
++}
++#endif
++
++#else
++static inline int forced_early_printk(const char *fmt, va_list ap)
++{
++	return 0;
++}
++#endif
++
+ #ifdef CONFIG_PRINTK
+ DECLARE_WAIT_QUEUE_HEAD(log_wait);
+ /* the next printk record to read by syslog(READ) or /proc/kmsg */
+@@ -1209,6 +1268,7 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
+ {
+ 	char *text;
+ 	int len = 0;
++	int attempts = 0;
+ 
+ 	text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL);
+ 	if (!text)
+@@ -1220,6 +1280,14 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
+ 		u64 seq;
+ 		u32 idx;
+ 		enum log_flags prev;
++		int num_msg;
++try_again:
++		attempts++;
++		if (attempts > 10) {
++			len = -EBUSY;
++			goto out;
++		}
++		num_msg = 0;
+ 
+ 		/*
+ 		 * Find first record that fits, including all following records,
+@@ -1235,6 +1303,14 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
+ 			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 */
+@@ -1248,6 +1324,14 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
+ 			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 */
+@@ -1288,6 +1372,7 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
+ 		clear_seq = log_next_seq;
+ 		clear_idx = log_next_idx;
+ 	}
++out:
+ 	raw_spin_unlock_irq(&logbuf_lock);
+ 
+ 	kfree(text);
+@@ -1443,6 +1528,12 @@ static void call_console_drivers(int level,
+ 	if (!console_drivers)
+ 		return;
+ 
++	if (IS_ENABLED(CONFIG_PREEMPT_RT_BASE)) {
++		if (in_irq() || in_nmi())
++			return;
++	}
++
++	migrate_disable();
+ 	for_each_console(con) {
+ 		if (exclusive_console && con != exclusive_console)
+ 			continue;
+@@ -1458,6 +1549,7 @@ static void call_console_drivers(int level,
+ 		else
+ 			con->write(con, text, len);
+ 	}
++	migrate_enable();
+ }
+ 
+ /*
+@@ -1620,6 +1712,13 @@ asmlinkage int vprintk_emit(int facility, int level,
+ 	/* cpu currently holding logbuf_lock in this function */
+ 	static unsigned int logbuf_cpu = UINT_MAX;
+ 
++	/*
++	 * Fall back to early_printk if a debugging subsystem has
++	 * killed printk output
++	 */
++	if (unlikely(forced_early_printk(fmt, args)))
++		return 1;
++
+ 	if (level == LOGLEVEL_SCHED) {
+ 		level = LOGLEVEL_DEFAULT;
+ 		in_sched = true;
+@@ -1755,13 +1854,23 @@ asmlinkage int vprintk_emit(int facility, int level,
+ 
+ 	/* If called from the scheduler, we can not call up(). */
+ 	if (!in_sched) {
++		int may_trylock = 1;
++
+ 		lockdep_off();
++#ifdef CONFIG_PREEMPT_RT_FULL
++		/*
++		 * we can't take a sleeping lock with IRQs or preeption disabled
++		 * so we can't print in these contexts
++		 */
++		if (!(preempt_count() == 0 && !irqs_disabled()))
++			may_trylock = 0;
++#endif
+ 		/*
+ 		 * Try to acquire and then immediately release the console
+ 		 * semaphore.  The release will print out buffers and wake up
+ 		 * /dev/kmsg and syslog() users.
+ 		 */
+-		if (console_trylock())
++		if (may_trylock && console_trylock())
+ 			console_unlock();
+ 		lockdep_on();
+ 	}
+@@ -1901,26 +2010,6 @@ DEFINE_PER_CPU(printk_func_t, printk_func);
+ 
+ #endif /* CONFIG_PRINTK */
+ 
+-#ifdef CONFIG_EARLY_PRINTK
+-struct console *early_console;
+-
+-asmlinkage __visible void early_printk(const char *fmt, ...)
+-{
+-	va_list ap;
+-	char buf[512];
+-	int n;
+-
+-	if (!early_console)
+-		return;
+-
+-	va_start(ap, fmt);
+-	n = vscnprintf(buf, sizeof(buf), fmt, ap);
+-	va_end(ap);
+-
+-	early_console->write(early_console, buf, n);
+-}
+-#endif
+-
+ static int __add_preferred_console(char *name, int idx, char *options,
+ 				   char *brl_options)
+ {
+@@ -2183,11 +2272,16 @@ static void console_cont_flush(char *text, size_t size)
+ 		goto out;
+ 
+ 	len = cont_print_text(text, size);
++#ifdef CONFIG_PREEMPT_RT_FULL
++	raw_spin_unlock_irqrestore(&logbuf_lock, flags);
++	call_console_drivers(cont.level, NULL, 0, text, len);
++#else
+ 	raw_spin_unlock(&logbuf_lock);
+ 	stop_critical_timings();
+ 	call_console_drivers(cont.level, NULL, 0, text, len);
+ 	start_critical_timings();
+ 	local_irq_restore(flags);
++#endif
+ 	return;
+ out:
+ 	raw_spin_unlock_irqrestore(&logbuf_lock, flags);
+@@ -2309,13 +2403,17 @@ void console_unlock(void)
+ 		console_idx = log_next(console_idx);
+ 		console_seq++;
+ 		console_prev = msg->flags;
++#ifdef CONFIG_PREEMPT_RT_FULL
++		raw_spin_unlock_irqrestore(&logbuf_lock, flags);
++		call_console_drivers(level, ext_text, ext_len, text, len);
++#else
+ 		raw_spin_unlock(&logbuf_lock);
+ 
+ 		stop_critical_timings();	/* don't trace print latency */
+ 		call_console_drivers(level, ext_text, ext_len, text, len);
+ 		start_critical_timings();
+ 		local_irq_restore(flags);
+-
++#endif
+ 		if (do_cond_resched)
+ 			cond_resched();
+ 	}
+@@ -2367,6 +2465,11 @@ void console_unblank(void)
+ {
+ 	struct console *c;
+ 
++	if (IS_ENABLED(CONFIG_PREEMPT_RT_BASE)) {
++		if (in_irq() || in_nmi())
++			return;
++	}
++
+ 	/*
+ 	 * console_unblank can no longer be called in interrupt context unless
+ 	 * oops_in_progress is set to 1..
+diff --git a/kernel/ptrace.c b/kernel/ptrace.c
+index d49bfa1e53e6..b8cf7a82f4e2 100644
+--- a/kernel/ptrace.c
++++ b/kernel/ptrace.c
+@@ -128,7 +128,14 @@ static bool ptrace_freeze_traced(struct task_struct *task)
+ 
+ 	spin_lock_irq(&task->sighand->siglock);
+ 	if (task_is_traced(task) && !__fatal_signal_pending(task)) {
+-		task->state = __TASK_TRACED;
++		unsigned long flags;
++
++		raw_spin_lock_irqsave(&task->pi_lock, flags);
++		if (task->state & __TASK_TRACED)
++			task->state = __TASK_TRACED;
++		else
++			task->saved_state = __TASK_TRACED;
++		raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+ 		ret = true;
+ 	}
+ 	spin_unlock_irq(&task->sighand->siglock);
+diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
+index 250ea67c1615..6349c9affa4d 100644
+--- a/kernel/rcu/rcutorture.c
++++ b/kernel/rcu/rcutorture.c
+@@ -409,6 +409,7 @@ static struct rcu_torture_ops rcu_ops = {
+ 	.name		= "rcu"
+ };
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
+ /*
+  * Definitions for rcu_bh torture testing.
+  */
+@@ -448,6 +449,12 @@ static struct rcu_torture_ops rcu_bh_ops = {
+ 	.name		= "rcu_bh"
+ };
+ 
++#else
++static struct rcu_torture_ops rcu_bh_ops = {
++	.ttype		= INVALID_RCU_FLAVOR,
++};
++#endif
++
+ /*
+  * Don't even think about trying any of these in real life!!!
+  * The names includes "busted", and they really means it!
+diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
+index 9a535a86e732..ae568fd4885b 100644
+--- a/kernel/rcu/tree.c
++++ b/kernel/rcu/tree.c
+@@ -56,6 +56,11 @@
+ #include <linux/random.h>
+ #include <linux/trace_events.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 "tree.h"
+ #include "rcu.h"
+@@ -254,6 +259,19 @@ void rcu_sched_qs(void)
+ 			   this_cpu_ptr(&rcu_sched_data), true);
+ }
+ 
++#ifdef CONFIG_PREEMPT_RT_FULL
++static void rcu_preempt_qs(void);
++
++void rcu_bh_qs(void)
++{
++	unsigned long flags;
++
++	/* Callers to this function, rcu_preempt_qs(), must disable irqs. */
++	local_irq_save(flags);
++	rcu_preempt_qs();
++	local_irq_restore(flags);
++}
++#else
+ void rcu_bh_qs(void)
+ {
+ 	if (__this_cpu_read(rcu_bh_data.cpu_no_qs.s)) {
+@@ -263,6 +281,7 @@ void rcu_bh_qs(void)
+ 		__this_cpu_write(rcu_bh_data.cpu_no_qs.b.norm, false);
+ 	}
+ }
++#endif
+ 
+ static DEFINE_PER_CPU(int, rcu_sched_qs_mask);
+ 
+@@ -426,11 +445,13 @@ EXPORT_SYMBOL_GPL(rcu_batches_started_sched);
+ /*
+  * Return the number of RCU BH batches started thus far for debug & stats.
+  */
++#ifndef CONFIG_PREEMPT_RT_FULL
+ unsigned long rcu_batches_started_bh(void)
+ {
+ 	return rcu_bh_state.gpnum;
+ }
+ EXPORT_SYMBOL_GPL(rcu_batches_started_bh);
++#endif
+ 
+ /*
+  * Return the number of RCU batches completed thus far for debug & stats.
+@@ -450,6 +471,7 @@ unsigned 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 completed thus far for debug & stats.
+  */
+@@ -477,6 +499,13 @@ void rcu_bh_force_quiescent_state(void)
+ }
+ EXPORT_SYMBOL_GPL(rcu_bh_force_quiescent_state);
+ 
++#else
++void rcu_force_quiescent_state(void)
++{
++}
++EXPORT_SYMBOL_GPL(rcu_force_quiescent_state);
++#endif
++
+ /*
+  * Force a quiescent state for RCU-sched.
+  */
+@@ -527,9 +556,11 @@ void rcutorture_get_gp_data(enum rcutorture_type test_type, int *flags,
+ 	case RCU_FLAVOR:
+ 		rsp = rcu_state_p;
+ 		break;
++#ifndef CONFIG_PREEMPT_RT_FULL
+ 	case RCU_BH_FLAVOR:
+ 		rsp = &rcu_bh_state;
+ 		break;
++#endif
+ 	case RCU_SCHED_FLAVOR:
+ 		rsp = &rcu_sched_state;
+ 		break;
+@@ -2920,18 +2951,17 @@ __rcu_process_callbacks(struct rcu_state *rsp)
+ /*
+  * 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"));
+ }
+ 
++static DEFINE_PER_CPU(struct task_struct *, rcu_cpu_kthread_task);
+ /*
+  * Schedule RCU callback invocation.  If the specified type of RCU
+  * does not support RCU priority boosting, just do a direct call,
+@@ -2943,19 +2973,106 @@ static void invoke_rcu_callbacks(struct rcu_state *rsp, struct rcu_data *rdp)
+ {
+ 	if (unlikely(!READ_ONCE(rcu_scheduler_fully_active)))
+ 		return;
+-	if (likely(!rsp->boost)) {
+-		rcu_do_batch(rsp, rdp);
+-		return;
+-	}
+-	invoke_rcu_callbacks_kthread();
++	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)
+ {
+-	if (cpu_online(smp_processor_id()))
+-		raise_softirq(RCU_SOFTIRQ);
++	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 = this_cpu_ptr(&rcu_cpu_kthread_status);
++	char work, *workp = this_cpu_ptr(&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;
++		}
++	}
++	*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 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)
++{
++	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.
+  */
+@@ -3099,6 +3216,7 @@ void call_rcu_sched(struct rcu_head *head, rcu_callback_t func)
+ }
+ EXPORT_SYMBOL_GPL(call_rcu_sched);
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
+ /*
+  * Queue an RCU callback for invocation after a quicker grace period.
+  */
+@@ -3107,6 +3225,7 @@ void call_rcu_bh(struct rcu_head *head, rcu_callback_t func)
+ 	__call_rcu(head, func, &rcu_bh_state, -1, 0);
+ }
+ EXPORT_SYMBOL_GPL(call_rcu_bh);
++#endif
+ 
+ /*
+  * Queue an RCU callback for lazy invocation after a grace period.
+@@ -3198,6 +3317,7 @@ 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.
+  *
+@@ -3224,6 +3344,7 @@ void synchronize_rcu_bh(void)
+ 		wait_rcu_gp(call_rcu_bh);
+ }
+ EXPORT_SYMBOL_GPL(synchronize_rcu_bh);
++#endif
+ 
+ /**
+  * get_state_synchronize_rcu - Snapshot current RCU state
+@@ -4104,6 +4225,7 @@ static void _rcu_barrier(struct rcu_state *rsp)
+ 	mutex_unlock(&rsp->barrier_mutex);
+ }
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
+ /**
+  * rcu_barrier_bh - Wait until all in-flight call_rcu_bh() callbacks complete.
+  */
+@@ -4112,6 +4234,7 @@ 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.
+@@ -4609,12 +4732,13 @@ void __init rcu_init(void)
+ 
+ 	rcu_bootup_announce();
+ 	rcu_init_geometry();
++#ifndef CONFIG_PREEMPT_RT_FULL
+ 	rcu_init_one(&rcu_bh_state);
++#endif
+ 	rcu_init_one(&rcu_sched_state);
+ 	if (dump_tree)
+ 		rcu_dump_rcu_node_tree(&rcu_sched_state);
+ 	__rcu_init_preempt();
+-	open_softirq(RCU_SOFTIRQ, rcu_process_callbacks);
+ 
+ 	/*
+ 	 * We don't need protection against CPU-hotplug here because
+diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h
+index df668c0f9e64..dd3efa3402fc 100644
+--- a/kernel/rcu/tree.h
++++ b/kernel/rcu/tree.h
+@@ -572,18 +572,18 @@ extern struct list_head rcu_struct_flavors;
+  */
+ extern struct rcu_state rcu_sched_state;
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
+ extern struct rcu_state rcu_bh_state;
++#endif
+ 
+ #ifdef CONFIG_PREEMPT_RCU
+ extern struct rcu_state rcu_preempt_state;
+ #endif /* #ifdef CONFIG_PREEMPT_RCU */
+ 
+-#ifdef CONFIG_RCU_BOOST
+ DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_status);
+ DECLARE_PER_CPU(int, rcu_cpu_kthread_cpu);
+ DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
+ DECLARE_PER_CPU(char, rcu_cpu_has_work);
+-#endif /* #ifdef CONFIG_RCU_BOOST */
+ 
+ #ifndef RCU_TREE_NONCORE
+ 
+@@ -603,10 +603,9 @@ void call_rcu(struct rcu_head *head, rcu_callback_t func);
+ 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 */
+diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
+index efdf7b61ce12..6a4158a83375 100644
+--- a/kernel/rcu/tree_plugin.h
++++ b/kernel/rcu/tree_plugin.h
+@@ -24,25 +24,10 @@
+  *	   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"
+-
+ #ifdef CONFIG_RCU_BOOST
+ 
+ #include "../locking/rtmutex_common.h"
+ 
+-/*
+- * Control variables for per-CPU and per-rcu_node kthreads.  These
+- * handle all flavors of RCU.
+- */
+-static DEFINE_PER_CPU(struct task_struct *, rcu_cpu_kthread_task);
+-DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_status);
+-DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
+-DEFINE_PER_CPU(char, rcu_cpu_has_work);
+-
+ #else /* #ifdef CONFIG_RCU_BOOST */
+ 
+ /*
+@@ -55,6 +40,14 @@ DEFINE_PER_CPU(char, rcu_cpu_has_work);
+ 
+ #endif /* #else #ifdef CONFIG_RCU_BOOST */
+ 
++/*
++ * Control variables for per-CPU and per-rcu_node kthreads.  These
++ * handle all flavors of RCU.
++ */
++DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_status);
++DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
++DEFINE_PER_CPU(char, rcu_cpu_has_work);
++
+ #ifdef CONFIG_RCU_NOCB_CPU
+ static cpumask_var_t rcu_nocb_mask; /* CPUs to have callbacks offloaded. */
+ static bool have_rcu_nocb_mask;	    /* Was rcu_nocb_mask allocated? */
+@@ -428,7 +421,7 @@ void rcu_read_unlock_special(struct task_struct *t)
+ 	}
+ 
+ 	/* Hardware IRQ handlers cannot block, complain if they get here. */
+-	if (in_irq() || in_serving_softirq()) {
++	if (preempt_count() & (HARDIRQ_MASK | SOFTIRQ_OFFSET)) {
+ 		lockdep_rcu_suspicious(__FILE__, __LINE__,
+ 				       "rcu_read_unlock() from irq or softirq with blocking in critical section!!!\n");
+ 		pr_alert("->rcu_read_unlock_special: %#x (b: %d, enq: %d nq: %d)\n",
+@@ -634,15 +627,6 @@ static void rcu_preempt_check_callbacks(void)
+ 		t->rcu_read_unlock_special.b.need_qs = true;
+ }
+ 
+-#ifdef CONFIG_RCU_BOOST
+-
+-static void rcu_preempt_do_callbacks(void)
+-{
+-	rcu_do_batch(rcu_state_p, this_cpu_ptr(rcu_data_p));
+-}
+-
+-#endif /* #ifdef CONFIG_RCU_BOOST */
+-
+ /*
+  * Queue a preemptible-RCU callback for invocation after a grace period.
+  */
+@@ -924,6 +908,19 @@ void exit_rcu(void)
+ 
+ #endif /* #else #ifdef CONFIG_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 = kthread_prio;
++	sched_setscheduler_nocheck(current, SCHED_FIFO, &sp);
++#endif /* #ifdef CONFIG_RCU_BOOST */
++}
++
+ #ifdef CONFIG_RCU_BOOST
+ 
+ #include "../locking/rtmutex_common.h"
+@@ -955,16 +952,6 @@ static void rcu_initiate_boost_trace(struct rcu_node *rnp)
+ 
+ #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
+@@ -1108,23 +1095,6 @@ static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags)
+ }
+ 
+ /*
+- * 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.
+  */
+@@ -1178,67 +1148,6 @@ static int rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
+ 	return 0;
+ }
+ 
+-static void rcu_kthread_do_work(void)
+-{
+-	rcu_do_batch(&rcu_sched_state, this_cpu_ptr(&rcu_sched_data));
+-	rcu_do_batch(&rcu_bh_state, this_cpu_ptr(&rcu_bh_data));
+-	rcu_preempt_do_callbacks();
+-}
+-
+-static void rcu_cpu_kthread_setup(unsigned int cpu)
+-{
+-	struct sched_param sp;
+-
+-	sp.sched_priority = 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 __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 = this_cpu_ptr(&rcu_cpu_kthread_status);
+-	char work, *workp = this_cpu_ptr(&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
+@@ -1268,26 +1177,12 @@ static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu)
+ 	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 boost kthreads -- called as soon as the scheduler is running.
+  */
+ static void __init rcu_spawn_boost_kthreads(void)
+ {
+ 	struct rcu_node *rnp;
+-	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));
+ 	rcu_for_each_leaf_node(rcu_state_p, rnp)
+ 		(void)rcu_spawn_one_boost_kthread(rcu_state_p, rnp);
+ }
+@@ -1310,11 +1205,6 @@ static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags)
+ 	raw_spin_unlock_irqrestore_rcu_node(rnp, flags);
+ }
+ 
+-static void invoke_rcu_callbacks_kthread(void)
+-{
+-	WARN_ON_ONCE(1);
+-}
+-
+ static bool rcu_is_callbacks_kthread(void)
+ {
+ 	return false;
+@@ -1338,7 +1228,7 @@ 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
+@@ -1355,7 +1245,9 @@ int rcu_needs_cpu(u64 basemono, u64 *nextevt)
+ 	return IS_ENABLED(CONFIG_RCU_NOCB_CPU_ALL)
+ 	       ? 0 : rcu_cpu_has_callbacks(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
+  * after it.
+@@ -1451,6 +1343,8 @@ static bool __maybe_unused 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
+@@ -1496,6 +1390,7 @@ int rcu_needs_cpu(u64 basemono, u64 *nextevt)
+ 	*nextevt = basemono + dj * TICK_NSEC;
+ 	return 0;
+ }
++#endif /* #ifndef CONFIG_PREEMPT_RT_FULL */
+ 
+ /*
+  * Prepare a CPU for idle from an RCU perspective.  The first major task
+diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c
+index ca828b41c938..6cbf7a9aa70f 100644
+--- a/kernel/rcu/update.c
++++ b/kernel/rcu/update.c
+@@ -295,6 +295,7 @@ int rcu_read_lock_held(void)
+ }
+ EXPORT_SYMBOL_GPL(rcu_read_lock_held);
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
+ /**
+  * rcu_read_lock_bh_held() - might we be in RCU-bh read-side critical section?
+  *
+@@ -321,6 +322,7 @@ 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 */
+ 
+diff --git a/kernel/relay.c b/kernel/relay.c
+index 074994bcfa9b..7206cef7d6da 100644
+--- a/kernel/relay.c
++++ b/kernel/relay.c
+@@ -336,6 +336,10 @@ static void wakeup_readers(unsigned long data)
+ {
+ 	struct rchan_buf *buf = (struct rchan_buf *)data;
+ 	wake_up_interruptible(&buf->read_wait);
++	/*
++	 * Stupid polling for now:
++	 */
++	mod_timer(&buf->timer, jiffies + 1);
+ }
+ 
+ /**
+@@ -353,6 +357,7 @@ static void __relay_reset(struct rchan_buf *buf, unsigned int init)
+ 		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);
+ 
+@@ -736,15 +741,6 @@ size_t relay_switch_subbuf(struct rchan_buf *buf, size_t length)
+ 		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;
+diff --git a/kernel/sched/Makefile b/kernel/sched/Makefile
+index 414d9c16da42..5aaddf5838e9 100644
+--- a/kernel/sched/Makefile
++++ b/kernel/sched/Makefile
+@@ -17,7 +17,7 @@ endif
+ 
+ obj-y += core.o loadavg.o clock.o cputime.o
+ obj-y += idle_task.o fair.o rt.o deadline.o stop_task.o
+-obj-y += wait.o swait.o completion.o idle.o
++obj-y += wait.o swait.o swork.o completion.o idle.o
+ obj-$(CONFIG_SMP) += cpupri.o cpudeadline.o
+ obj-$(CONFIG_SCHED_AUTOGROUP) += auto_group.o
+ obj-$(CONFIG_SCHEDSTATS) += stats.o
+diff --git a/kernel/sched/completion.c b/kernel/sched/completion.c
+index 8d0f35debf35..b62cf6400fe0 100644
+--- a/kernel/sched/completion.c
++++ b/kernel/sched/completion.c
+@@ -30,10 +30,10 @@ void complete(struct completion *x)
+ {
+ 	unsigned long flags;
+ 
+-	spin_lock_irqsave(&x->wait.lock, flags);
++	raw_spin_lock_irqsave(&x->wait.lock, flags);
+ 	x->done++;
+-	__wake_up_locked(&x->wait, TASK_NORMAL, 1);
+-	spin_unlock_irqrestore(&x->wait.lock, flags);
++	swake_up_locked(&x->wait);
++	raw_spin_unlock_irqrestore(&x->wait.lock, flags);
+ }
+ EXPORT_SYMBOL(complete);
+ 
+@@ -50,10 +50,10 @@ void complete_all(struct completion *x)
+ {
+ 	unsigned long flags;
+ 
+-	spin_lock_irqsave(&x->wait.lock, flags);
++	raw_spin_lock_irqsave(&x->wait.lock, flags);
+ 	x->done += UINT_MAX/2;
+-	__wake_up_locked(&x->wait, TASK_NORMAL, 0);
+-	spin_unlock_irqrestore(&x->wait.lock, flags);
++	swake_up_all_locked(&x->wait);
++	raw_spin_unlock_irqrestore(&x->wait.lock, flags);
+ }
+ EXPORT_SYMBOL(complete_all);
+ 
+@@ -62,20 +62,20 @@ do_wait_for_common(struct completion *x,
+ 		   long (*action)(long), long timeout, int state)
+ {
+ 	if (!x->done) {
+-		DECLARE_WAITQUEUE(wait, current);
++		DECLARE_SWAITQUEUE(wait);
+ 
+-		__add_wait_queue_tail_exclusive(&x->wait, &wait);
++		__prepare_to_swait(&x->wait, &wait);
+ 		do {
+ 			if (signal_pending_state(state, current)) {
+ 				timeout = -ERESTARTSYS;
+ 				break;
+ 			}
+ 			__set_current_state(state);
+-			spin_unlock_irq(&x->wait.lock);
++			raw_spin_unlock_irq(&x->wait.lock);
+ 			timeout = action(timeout);
+-			spin_lock_irq(&x->wait.lock);
++			raw_spin_lock_irq(&x->wait.lock);
+ 		} while (!x->done && timeout);
+-		__remove_wait_queue(&x->wait, &wait);
++		__finish_swait(&x->wait, &wait);
+ 		if (!x->done)
+ 			return timeout;
+ 	}
+@@ -89,9 +89,9 @@ __wait_for_common(struct completion *x,
+ {
+ 	might_sleep();
+ 
+-	spin_lock_irq(&x->wait.lock);
++	raw_spin_lock_irq(&x->wait.lock);
+ 	timeout = do_wait_for_common(x, action, timeout, state);
+-	spin_unlock_irq(&x->wait.lock);
++	raw_spin_unlock_irq(&x->wait.lock);
+ 	return timeout;
+ }
+ 
+@@ -277,12 +277,12 @@ bool try_wait_for_completion(struct completion *x)
+ 	if (!READ_ONCE(x->done))
+ 		return 0;
+ 
+-	spin_lock_irqsave(&x->wait.lock, flags);
++	raw_spin_lock_irqsave(&x->wait.lock, flags);
+ 	if (!x->done)
+ 		ret = 0;
+ 	else
+ 		x->done--;
+-	spin_unlock_irqrestore(&x->wait.lock, flags);
++	raw_spin_unlock_irqrestore(&x->wait.lock, flags);
+ 	return ret;
+ }
+ EXPORT_SYMBOL(try_wait_for_completion);
+@@ -311,7 +311,7 @@ bool completion_done(struct completion *x)
+ 	 * after it's acquired the lock.
+ 	 */
+ 	smp_rmb();
+-	spin_unlock_wait(&x->wait.lock);
++	raw_spin_unlock_wait(&x->wait.lock);
+ 	return true;
+ }
+ EXPORT_SYMBOL(completion_done);
+diff --git a/kernel/sched/core.c b/kernel/sched/core.c
+index 11546a6ed5df..140ee06079b6 100644
+--- a/kernel/sched/core.c
++++ b/kernel/sched/core.c
+@@ -128,7 +128,11 @@ const_debug unsigned int sysctl_sched_features =
+  * Number of tasks to iterate in a single balance run.
+  * Limited because this is done with IRQs disabled.
+  */
++#ifndef CONFIG_PREEMPT_RT_FULL
+ const_debug unsigned int sysctl_sched_nr_migrate = 32;
++#else
++const_debug unsigned int sysctl_sched_nr_migrate = 8;
++#endif
+ 
+ /*
+  * period over which we average the RT time consumption, measured
+@@ -306,6 +310,7 @@ static void init_rq_hrtick(struct rq *rq)
+ 
+ 	hrtimer_init(&rq->hrtick_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ 	rq->hrtick_timer.function = hrtick;
++	rq->hrtick_timer.irqsafe = 1;
+ }
+ #else	/* CONFIG_SCHED_HRTICK */
+ static inline void hrtick_clear(struct rq *rq)
+@@ -414,7 +419,7 @@ void wake_q_add(struct wake_q_head *head, struct task_struct *task)
+ 	head->lastp = &node->next;
+ }
+ 
+-void wake_up_q(struct wake_q_head *head)
++void __wake_up_q(struct wake_q_head *head, bool sleeper)
+ {
+ 	struct wake_q_node *node = head->first;
+ 
+@@ -431,7 +436,10 @@ void wake_up_q(struct wake_q_head *head)
+ 		 * wake_up_process() implies a wmb() to pair with the queueing
+ 		 * in wake_q_add() so as not to miss wakeups.
+ 		 */
+-		wake_up_process(task);
++		if (sleeper)
++			wake_up_lock_sleeper(task);
++		else
++			wake_up_process(task);
+ 		put_task_struct(task);
+ 	}
+ }
+@@ -467,6 +475,38 @@ void resched_curr(struct rq *rq)
+ 		trace_sched_wake_idle_without_ipi(cpu);
+ }
+ 
++#ifdef CONFIG_PREEMPT_LAZY
++void resched_curr_lazy(struct rq *rq)
++{
++	struct task_struct *curr = rq->curr;
++	int cpu;
++
++	if (!sched_feat(PREEMPT_LAZY)) {
++		resched_curr(rq);
++		return;
++	}
++
++	lockdep_assert_held(&rq->lock);
++
++	if (test_tsk_need_resched(curr))
++		return;
++
++	if (test_tsk_need_resched_lazy(curr))
++		return;
++
++	set_tsk_need_resched_lazy(curr);
++
++	cpu = cpu_of(rq);
++	if (cpu == smp_processor_id())
++		return;
++
++	/* NEED_RESCHED_LAZY must be visible before we test polling */
++	smp_mb();
++	if (!tsk_is_polling(curr))
++		smp_send_reschedule(cpu);
++}
++#endif
++
+ void resched_cpu(int cpu)
+ {
+ 	struct rq *rq = cpu_rq(cpu);
+@@ -490,11 +530,14 @@ void resched_cpu(int cpu)
+  */
+ int get_nohz_timer_target(void)
+ {
+-	int i, cpu = smp_processor_id();
++	int i, cpu;
+ 	struct sched_domain *sd;
+ 
++	preempt_disable_rt();
++	cpu = smp_processor_id();
++
+ 	if (!idle_cpu(cpu) && is_housekeeping_cpu(cpu))
+-		return cpu;
++		goto preempt_en_rt;
+ 
+ 	rcu_read_lock();
+ 	for_each_domain(cpu, sd) {
+@@ -510,6 +553,8 @@ int get_nohz_timer_target(void)
+ 		cpu = housekeeping_any_cpu();
+ unlock:
+ 	rcu_read_unlock();
++preempt_en_rt:
++	preempt_enable_rt();
+ 	return cpu;
+ }
+ /*
+@@ -1051,6 +1096,11 @@ void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
+ 
+ 	lockdep_assert_held(&p->pi_lock);
+ 
++	if (__migrate_disabled(p)) {
++		cpumask_copy(&p->cpus_allowed, new_mask);
++		return;
++	}
++
+ 	queued = task_on_rq_queued(p);
+ 	running = task_current(rq, p);
+ 
+@@ -1073,6 +1123,84 @@ void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
+ 		enqueue_task(rq, p, ENQUEUE_RESTORE);
+ }
+ 
++static DEFINE_PER_CPU(struct cpumask, sched_cpumasks);
++static DEFINE_MUTEX(sched_down_mutex);
++static cpumask_t sched_down_cpumask;
++
++void tell_sched_cpu_down_begin(int cpu)
++{
++	mutex_lock(&sched_down_mutex);
++	cpumask_set_cpu(cpu, &sched_down_cpumask);
++	mutex_unlock(&sched_down_mutex);
++}
++
++void tell_sched_cpu_down_done(int cpu)
++{
++	mutex_lock(&sched_down_mutex);
++	cpumask_clear_cpu(cpu, &sched_down_cpumask);
++	mutex_unlock(&sched_down_mutex);
++}
++
++/**
++ * migrate_me - try to move the current task off this cpu
++ *
++ * Used by the pin_current_cpu() code to try to get tasks
++ * to move off the current CPU as it is going down.
++ * It will only move the task if the task isn't pinned to
++ * the CPU (with migrate_disable, affinity or NO_SETAFFINITY)
++ * and the task has to be in a RUNNING state. Otherwise the
++ * movement of the task will wake it up (change its state
++ * to running) when the task did not expect it.
++ *
++ * Returns 1 if it succeeded in moving the current task
++ *         0 otherwise.
++ */
++int migrate_me(void)
++{
++	struct task_struct *p = current;
++	struct migration_arg arg;
++	struct cpumask *cpumask;
++	struct cpumask *mask;
++	unsigned long flags;
++	unsigned int dest_cpu;
++	struct rq *rq;
++
++	/*
++	 * We can not migrate tasks bounded to a CPU or tasks not
++	 * running. The movement of the task will wake it up.
++	 */
++	if (p->flags & PF_NO_SETAFFINITY || p->state)
++		return 0;
++
++	mutex_lock(&sched_down_mutex);
++	rq = task_rq_lock(p, &flags);
++
++	cpumask = this_cpu_ptr(&sched_cpumasks);
++	mask = &p->cpus_allowed;
++
++	cpumask_andnot(cpumask, mask, &sched_down_cpumask);
++
++	if (!cpumask_weight(cpumask)) {
++		/* It's only on this CPU? */
++		task_rq_unlock(rq, p, &flags);
++		mutex_unlock(&sched_down_mutex);
++		return 0;
++	}
++
++	dest_cpu = cpumask_any_and(cpu_active_mask, cpumask);
++
++	arg.task = p;
++	arg.dest_cpu = dest_cpu;
++
++	task_rq_unlock(rq, p, &flags);
++
++	stop_one_cpu(cpu_of(rq), migration_cpu_stop, &arg);
++	tlb_migrate_finish(p->mm);
++	mutex_unlock(&sched_down_mutex);
++
++	return 1;
++}
++
+ /*
+  * Change a given task's CPU affinity. Migrate the thread to a
+  * proper CPU and schedule it away if the CPU it's executing on
+@@ -1112,7 +1240,7 @@ static int __set_cpus_allowed_ptr(struct task_struct *p,
+ 	do_set_cpus_allowed(p, new_mask);
+ 
+ 	/* Can the task run on the task's current CPU? If so, we're done */
+-	if (cpumask_test_cpu(task_cpu(p), new_mask))
++	if (cpumask_test_cpu(task_cpu(p), new_mask) || __migrate_disabled(p))
+ 		goto out;
+ 
+ 	dest_cpu = cpumask_any_and(cpu_active_mask, new_mask);
+@@ -1299,6 +1427,18 @@ int migrate_swap(struct task_struct *cur, struct task_struct *p)
+ 	return ret;
+ }
+ 
++static bool check_task_state(struct task_struct *p, long match_state)
++{
++	bool match = false;
++
++	raw_spin_lock_irq(&p->pi_lock);
++	if (p->state == match_state || p->saved_state == match_state)
++		match = true;
++	raw_spin_unlock_irq(&p->pi_lock);
++
++	return match;
++}
++
+ /*
+  * wait_task_inactive - wait for a thread to unschedule.
+  *
+@@ -1343,7 +1483,7 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state)
+ 		 * is actually now running somewhere else!
+ 		 */
+ 		while (task_running(rq, p)) {
+-			if (match_state && unlikely(p->state != match_state))
++			if (match_state && !check_task_state(p, match_state))
+ 				return 0;
+ 			cpu_relax();
+ 		}
+@@ -1358,7 +1498,8 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state)
+ 		running = task_running(rq, p);
+ 		queued = task_on_rq_queued(p);
+ 		ncsw = 0;
+-		if (!match_state || p->state == match_state)
++		if (!match_state || p->state == match_state ||
++		    p->saved_state == match_state)
+ 			ncsw = p->nvcsw | LONG_MIN; /* sets MSB */
+ 		task_rq_unlock(rq, p, &flags);
+ 
+@@ -1515,7 +1656,7 @@ int select_task_rq(struct task_struct *p, int cpu, int sd_flags, int wake_flags)
+ {
+ 	lockdep_assert_held(&p->pi_lock);
+ 
+-	if (p->nr_cpus_allowed > 1)
++	if (tsk_nr_cpus_allowed(p) > 1)
+ 		cpu = p->sched_class->select_task_rq(p, cpu, sd_flags, wake_flags);
+ 
+ 	/*
+@@ -1595,10 +1736,6 @@ static inline void ttwu_activate(struct rq *rq, struct task_struct *p, int en_fl
+ {
+ 	activate_task(rq, p, en_flags);
+ 	p->on_rq = TASK_ON_RQ_QUEUED;
+-
+-	/* if a worker is waking up, notify workqueue */
+-	if (p->flags & PF_WQ_WORKER)
+-		wq_worker_waking_up(p, cpu_of(rq));
+ }
+ 
+ /*
+@@ -1916,8 +2053,27 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
+ 	 */
+ 	smp_mb__before_spinlock();
+ 	raw_spin_lock_irqsave(&p->pi_lock, flags);
+-	if (!(p->state & state))
++	if (!(p->state & state)) {
++		/*
++		 * The task might be running due to a spinlock sleeper
++		 * wakeup. Check the saved state and set it to running
++		 * if the wakeup condition is true.
++		 */
++		if (!(wake_flags & WF_LOCK_SLEEPER)) {
++			if (p->saved_state & state) {
++				p->saved_state = TASK_RUNNING;
++				success = 1;
++			}
++		}
+ 		goto out;
++	}
++
++	/*
++	 * If this is a regular wakeup, then we can unconditionally
++	 * clear the saved state of a "lock sleeper".
++	 */
++	if (!(wake_flags & WF_LOCK_SLEEPER))
++		p->saved_state = TASK_RUNNING;
+ 
+ 	trace_sched_waking(p);
+ 
+@@ -1982,53 +2138,6 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
+ }
+ 
+ /**
+- * try_to_wake_up_local - try to wake up a local task with rq lock held
+- * @p: the thread to be awakened
+- *
+- * Put @p on the run-queue if it's not already there. The caller must
+- * ensure that this_rq() is locked, @p is bound to this_rq() and not
+- * the current task.
+- */
+-static void try_to_wake_up_local(struct task_struct *p)
+-{
+-	struct rq *rq = task_rq(p);
+-
+-	if (WARN_ON_ONCE(rq != this_rq()) ||
+-	    WARN_ON_ONCE(p == current))
+-		return;
+-
+-	lockdep_assert_held(&rq->lock);
+-
+-	if (!raw_spin_trylock(&p->pi_lock)) {
+-		/*
+-		 * This is OK, because current is on_cpu, which avoids it being
+-		 * picked for load-balance and preemption/IRQs are still
+-		 * disabled avoiding further scheduler activity on it and we've
+-		 * not yet picked a replacement task.
+-		 */
+-		lockdep_unpin_lock(&rq->lock);
+-		raw_spin_unlock(&rq->lock);
+-		raw_spin_lock(&p->pi_lock);
+-		raw_spin_lock(&rq->lock);
+-		lockdep_pin_lock(&rq->lock);
+-	}
+-
+-	if (!(p->state & TASK_NORMAL))
+-		goto out;
+-
+-	trace_sched_waking(p);
+-
+-	if (!task_on_rq_queued(p))
+-		ttwu_activate(rq, p, ENQUEUE_WAKEUP);
+-
+-	ttwu_do_wakeup(rq, p, 0);
+-	if (schedstat_enabled())
+-		ttwu_stat(p, smp_processor_id(), 0);
+-out:
+-	raw_spin_unlock(&p->pi_lock);
+-}
+-
+-/**
+  * wake_up_process - Wake up a specific process
+  * @p: The process to be woken up.
+  *
+@@ -2046,6 +2155,18 @@ int wake_up_process(struct task_struct *p)
+ }
+ EXPORT_SYMBOL(wake_up_process);
+ 
++/**
++ * wake_up_lock_sleeper - Wake up a specific process blocked on a "sleeping lock"
++ * @p: The process to be woken up.
++ *
++ * Same as wake_up_process() above, but wake_flags=WF_LOCK_SLEEPER to indicate
++ * the nature of the wakeup.
++ */
++int wake_up_lock_sleeper(struct task_struct *p)
++{
++	return try_to_wake_up(p, TASK_ALL, WF_LOCK_SLEEPER);
++}
++
+ int wake_up_state(struct task_struct *p, unsigned int state)
+ {
+ 	return try_to_wake_up(p, state, 0);
+@@ -2303,6 +2424,9 @@ int sched_fork(unsigned long clone_flags, struct task_struct *p)
+ 	p->on_cpu = 0;
+ #endif
+ 	init_task_preempt_count(p);
++#ifdef CONFIG_HAVE_PREEMPT_LAZY
++	task_thread_info(p)->preempt_lazy_count = 0;
++#endif
+ #ifdef CONFIG_SMP
+ 	plist_node_init(&p->pushable_tasks, MAX_PRIO);
+ 	RB_CLEAR_NODE(&p->pushable_dl_tasks);
+@@ -2627,8 +2751,12 @@ static struct rq *finish_task_switch(struct task_struct *prev)
+ 	finish_arch_post_lock_switch();
+ 
+ 	fire_sched_in_preempt_notifiers(current);
++	/*
++	 * We use mmdrop_delayed() here so we don't have to do the
++	 * full __mmdrop() when we are the last user.
++	 */
+ 	if (mm)
+-		mmdrop(mm);
++		mmdrop_delayed(mm);
+ 	if (unlikely(prev_state == TASK_DEAD)) {
+ 		if (prev->sched_class->task_dead)
+ 			prev->sched_class->task_dead(prev);
+@@ -3062,6 +3190,77 @@ static inline void schedule_debug(struct task_struct *prev)
+ 	schedstat_inc(this_rq(), sched_count);
+ }
+ 
++#if defined(CONFIG_PREEMPT_RT_FULL) && defined(CONFIG_SMP)
++
++void migrate_disable(void)
++{
++	struct task_struct *p = current;
++
++	if (in_atomic() || irqs_disabled()) {
++#ifdef CONFIG_SCHED_DEBUG
++		p->migrate_disable_atomic++;
++#endif
++		return;
++	}
++
++#ifdef CONFIG_SCHED_DEBUG
++	if (unlikely(p->migrate_disable_atomic)) {
++		tracing_off();
++		WARN_ON_ONCE(1);
++	}
++#endif
++
++	if (p->migrate_disable) {
++		p->migrate_disable++;
++		return;
++	}
++
++	preempt_disable();
++	preempt_lazy_disable();
++	pin_current_cpu();
++	p->migrate_disable = 1;
++	preempt_enable();
++}
++EXPORT_SYMBOL(migrate_disable);
++
++void migrate_enable(void)
++{
++	struct task_struct *p = current;
++
++	if (in_atomic() || irqs_disabled()) {
++#ifdef CONFIG_SCHED_DEBUG
++		p->migrate_disable_atomic--;
++#endif
++		return;
++	}
++
++#ifdef CONFIG_SCHED_DEBUG
++	if (unlikely(p->migrate_disable_atomic)) {
++		tracing_off();
++		WARN_ON_ONCE(1);
++	}
++#endif
++	WARN_ON_ONCE(p->migrate_disable <= 0);
++
++	if (p->migrate_disable > 1) {
++		p->migrate_disable--;
++		return;
++	}
++
++	preempt_disable();
++	/*
++	 * Clearing migrate_disable causes tsk_cpus_allowed to
++	 * show the tasks original cpu affinity.
++	 */
++	p->migrate_disable = 0;
++
++	unpin_current_cpu();
++	preempt_enable();
++	preempt_lazy_enable();
++}
++EXPORT_SYMBOL(migrate_enable);
++#endif
++
+ /*
+  * Pick up the highest-prio task:
+  */
+@@ -3188,19 +3387,6 @@ static void __sched notrace __schedule(bool preempt)
+ 		} else {
+ 			deactivate_task(rq, prev, DEQUEUE_SLEEP);
+ 			prev->on_rq = 0;
+-
+-			/*
+-			 * If a worker went to sleep, notify and ask workqueue
+-			 * whether it wants to wake up a task to maintain
+-			 * concurrency.
+-			 */
+-			if (prev->flags & PF_WQ_WORKER) {
+-				struct task_struct *to_wakeup;
+-
+-				to_wakeup = wq_worker_sleeping(prev);
+-				if (to_wakeup)
+-					try_to_wake_up_local(to_wakeup);
+-			}
+ 		}
+ 		switch_count = &prev->nvcsw;
+ 	}
+@@ -3210,6 +3396,7 @@ static void __sched notrace __schedule(bool preempt)
+ 
+ 	next = pick_next_task(rq, prev);
+ 	clear_tsk_need_resched(prev);
++	clear_tsk_need_resched_lazy(prev);
+ 	clear_preempt_need_resched();
+ 	rq->clock_skip_update = 0;
+ 
+@@ -3231,9 +3418,20 @@ STACK_FRAME_NON_STANDARD(__schedule); /* switch_to() */
+ 
+ static inline void sched_submit_work(struct task_struct *tsk)
+ {
+-	if (!tsk->state || tsk_is_pi_blocked(tsk))
++	if (!tsk->state)
+ 		return;
+ 	/*
++	 * If a worker went to sleep, notify and ask workqueue whether
++	 * it wants to wake up a task to maintain concurrency.
++	 */
++	if (tsk->flags & PF_WQ_WORKER)
++		wq_worker_sleeping(tsk);
++
++
++	if (tsk_is_pi_blocked(tsk))
++		return;
++
++	/*
+ 	 * If we are going to sleep and we have plugged IO queued,
+ 	 * make sure to submit it to avoid deadlocks.
+ 	 */
+@@ -3241,6 +3439,12 @@ static inline void sched_submit_work(struct task_struct *tsk)
+ 		blk_schedule_flush_plug(tsk);
+ }
+ 
++static void sched_update_worker(struct task_struct *tsk)
++{
++	if (tsk->flags & PF_WQ_WORKER)
++		wq_worker_running(tsk);
++}
++
+ asmlinkage __visible void __sched schedule(void)
+ {
+ 	struct task_struct *tsk = current;
+@@ -3251,6 +3455,7 @@ asmlinkage __visible void __sched schedule(void)
+ 		__schedule(false);
+ 		sched_preempt_enable_no_resched();
+ 	} while (need_resched());
++	sched_update_worker(tsk);
+ }
+ EXPORT_SYMBOL(schedule);
+ 
+@@ -3299,6 +3504,30 @@ static void __sched notrace preempt_schedule_common(void)
+ 	} while (need_resched());
+ }
+ 
++#ifdef CONFIG_PREEMPT_LAZY
++/*
++ * If TIF_NEED_RESCHED is then we allow to be scheduled away since this is
++ * set by a RT task. Oterwise we try to avoid beeing scheduled out as long as
++ * preempt_lazy_count counter >0.
++ */
++static __always_inline int preemptible_lazy(void)
++{
++	if (test_thread_flag(TIF_NEED_RESCHED))
++		return 1;
++	if (current_thread_info()->preempt_lazy_count)
++		return 0;
++	return 1;
++}
++
++#else
++
++static inline int preemptible_lazy(void)
++{
++	return 1;
++}
++
++#endif
++
+ #ifdef CONFIG_PREEMPT
+ /*
+  * this is the entry point to schedule() from in-kernel preemption
+@@ -3313,6 +3542,8 @@ asmlinkage __visible void __sched notrace preempt_schedule(void)
+ 	 */
+ 	if (likely(!preemptible()))
+ 		return;
++	if (!preemptible_lazy())
++		return;
+ 
+ 	preempt_schedule_common();
+ }
+@@ -3339,6 +3570,8 @@ asmlinkage __visible void __sched notrace preempt_schedule_notrace(void)
+ 
+ 	if (likely(!preemptible()))
+ 		return;
++	if (!preemptible_lazy())
++		return;
+ 
+ 	do {
+ 		preempt_disable_notrace();
+@@ -3348,7 +3581,16 @@ asmlinkage __visible void __sched notrace preempt_schedule_notrace(void)
+ 		 * an infinite recursion.
+ 		 */
+ 		prev_ctx = exception_enter();
++		/*
++		 * The add/subtract must not be traced by the function
++		 * tracer. But we still want to account for the
++		 * preempt off latency tracer. Since the _notrace versions
++		 * of add/subtract skip the accounting for latency tracer
++		 * we must force it manually.
++		 */
++		start_critical_timings();
+ 		__schedule(true);
++		stop_critical_timings();
+ 		exception_exit(prev_ctx);
+ 
+ 		preempt_enable_no_resched_notrace();
+@@ -4693,6 +4935,7 @@ int __cond_resched_lock(spinlock_t *lock)
+ }
+ EXPORT_SYMBOL(__cond_resched_lock);
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
+ int __sched __cond_resched_softirq(void)
+ {
+ 	BUG_ON(!in_softirq());
+@@ -4706,6 +4949,7 @@ int __sched __cond_resched_softirq(void)
+ 	return 0;
+ }
+ EXPORT_SYMBOL(__cond_resched_softirq);
++#endif
+ 
+ /**
+  * yield - yield the current processor to other threads.
+@@ -5072,7 +5316,9 @@ void init_idle(struct task_struct *idle, int cpu)
+ 
+ 	/* Set the preempt count _outside_ the spinlocks! */
+ 	init_idle_preempt_count(idle, cpu);
+-
++#ifdef CONFIG_HAVE_PREEMPT_LAZY
++	task_thread_info(idle)->preempt_lazy_count = 0;
++#endif
+ 	/*
+ 	 * The idle tasks have their own, simple scheduling class:
+ 	 */
+@@ -5213,6 +5459,8 @@ void sched_setnuma(struct task_struct *p, int nid)
+ #endif /* CONFIG_NUMA_BALANCING */
+ 
+ #ifdef CONFIG_HOTPLUG_CPU
++static DEFINE_PER_CPU(struct mm_struct *, idle_last_mm);
++
+ /*
+  * Ensures that the idle task is using init_mm right before its cpu goes
+  * offline.
+@@ -5227,7 +5475,11 @@ void idle_task_exit(void)
+ 		switch_mm(mm, &init_mm, current);
+ 		finish_arch_post_lock_switch();
+ 	}
+-	mmdrop(mm);
++	/*
++	 * Defer the cleanup to an alive cpu. On RT we can neither
++	 * call mmdrop() nor mmdrop_delayed() from here.
++	 */
++	per_cpu(idle_last_mm, smp_processor_id()) = mm;
+ }
+ 
+ /*
+@@ -5423,6 +5675,10 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
+ 
+ 	case CPU_DEAD:
+ 		calc_load_migrate(rq);
++		if (per_cpu(idle_last_mm, cpu)) {
++			mmdrop(per_cpu(idle_last_mm, cpu));
++			per_cpu(idle_last_mm, cpu) = NULL;
++		}
+ 		break;
+ #endif
+ 	}
+@@ -7405,7 +7661,7 @@ void __init sched_init(void)
+ #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
+ static inline int preempt_count_equals(int preempt_offset)
+ {
+-	int nested = preempt_count() + rcu_preempt_depth();
++	int nested = preempt_count() + sched_rcu_preempt_depth();
+ 
+ 	return (nested == preempt_offset);
+ }
+diff --git a/kernel/sched/cpudeadline.c b/kernel/sched/cpudeadline.c
+index 5a75b08cfd85..5be58820465c 100644
+--- a/kernel/sched/cpudeadline.c
++++ b/kernel/sched/cpudeadline.c
+@@ -103,10 +103,10 @@ int cpudl_find(struct cpudl *cp, struct task_struct *p,
+ 	const struct sched_dl_entity *dl_se = &p->dl;
+ 
+ 	if (later_mask &&
+-	    cpumask_and(later_mask, cp->free_cpus, &p->cpus_allowed)) {
++	    cpumask_and(later_mask, cp->free_cpus, tsk_cpus_allowed(p))) {
+ 		best_cpu = cpumask_any(later_mask);
+ 		goto out;
+-	} else if (cpumask_test_cpu(cpudl_maximum(cp), &p->cpus_allowed) &&
++	} else if (cpumask_test_cpu(cpudl_maximum(cp), tsk_cpus_allowed(p)) &&
+ 			dl_time_before(dl_se->deadline, cp->elements[0].dl)) {
+ 		best_cpu = cpudl_maximum(cp);
+ 		if (later_mask)
+diff --git a/kernel/sched/cpupri.c b/kernel/sched/cpupri.c
+index 981fcd7dc394..11e9705bf937 100644
+--- a/kernel/sched/cpupri.c
++++ b/kernel/sched/cpupri.c
+@@ -103,11 +103,11 @@ int cpupri_find(struct cpupri *cp, struct task_struct *p,
+ 		if (skip)
+ 			continue;
+ 
+-		if (cpumask_any_and(&p->cpus_allowed, vec->mask) >= nr_cpu_ids)
++		if (cpumask_any_and(tsk_cpus_allowed(p), vec->mask) >= nr_cpu_ids)
+ 			continue;
+ 
+ 		if (lowest_mask) {
+-			cpumask_and(lowest_mask, &p->cpus_allowed, vec->mask);
++			cpumask_and(lowest_mask, tsk_cpus_allowed(p), vec->mask);
+ 
+ 			/*
+ 			 * We have to ensure that we have at least one bit
+diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
+index 686ec8adf952..8099333b5e1d 100644
+--- a/kernel/sched/deadline.c
++++ b/kernel/sched/deadline.c
+@@ -134,7 +134,7 @@ static void inc_dl_migration(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq)
+ {
+ 	struct task_struct *p = dl_task_of(dl_se);
+ 
+-	if (p->nr_cpus_allowed > 1)
++	if (tsk_nr_cpus_allowed(p) > 1)
+ 		dl_rq->dl_nr_migratory++;
+ 
+ 	update_dl_migration(dl_rq);
+@@ -144,7 +144,7 @@ static void dec_dl_migration(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq)
+ {
+ 	struct task_struct *p = dl_task_of(dl_se);
+ 
+-	if (p->nr_cpus_allowed > 1)
++	if (tsk_nr_cpus_allowed(p) > 1)
+ 		dl_rq->dl_nr_migratory--;
+ 
+ 	update_dl_migration(dl_rq);
+@@ -694,6 +694,7 @@ void init_dl_task_timer(struct sched_dl_entity *dl_se)
+ 
+ 	hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ 	timer->function = dl_task_timer;
++	timer->irqsafe = 1;
+ }
+ 
+ static
+@@ -966,7 +967,7 @@ static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags)
+ 
+ 	enqueue_dl_entity(&p->dl, pi_se, flags);
+ 
+-	if (!task_current(rq, p) && p->nr_cpus_allowed > 1)
++	if (!task_current(rq, p) && tsk_nr_cpus_allowed(p) > 1)
+ 		enqueue_pushable_dl_task(rq, p);
+ }
+ 
+@@ -1040,9 +1041,9 @@ select_task_rq_dl(struct task_struct *p, int cpu, int sd_flag, int flags)
+ 	 * try to make it stay here, it might be important.
+ 	 */
+ 	if (unlikely(dl_task(curr)) &&
+-	    (curr->nr_cpus_allowed < 2 ||
++	    (tsk_nr_cpus_allowed(curr) < 2 ||
+ 	     !dl_entity_preempt(&p->dl, &curr->dl)) &&
+-	    (p->nr_cpus_allowed > 1)) {
++	    (tsk_nr_cpus_allowed(p) > 1)) {
+ 		int target = find_later_rq(p);
+ 
+ 		if (target != -1 &&
+@@ -1063,7 +1064,7 @@ static void check_preempt_equal_dl(struct rq *rq, struct task_struct *p)
+ 	 * Current can't be migrated, useless to reschedule,
+ 	 * let's hope p can move out.
+ 	 */
+-	if (rq->curr->nr_cpus_allowed == 1 ||
++	if (tsk_nr_cpus_allowed(rq->curr) == 1 ||
+ 	    cpudl_find(&rq->rd->cpudl, rq->curr, NULL) == -1)
+ 		return;
+ 
+@@ -1071,7 +1072,7 @@ static void check_preempt_equal_dl(struct rq *rq, struct task_struct *p)
+ 	 * p is migratable, so let's not schedule it and
+ 	 * see if it is pushed or pulled somewhere else.
+ 	 */
+-	if (p->nr_cpus_allowed != 1 &&
++	if (tsk_nr_cpus_allowed(p) != 1 &&
+ 	    cpudl_find(&rq->rd->cpudl, p, NULL) != -1)
+ 		return;
+ 
+@@ -1185,7 +1186,7 @@ static void put_prev_task_dl(struct rq *rq, struct task_struct *p)
+ {
+ 	update_curr_dl(rq);
+ 
+-	if (on_dl_rq(&p->dl) && p->nr_cpus_allowed > 1)
++	if (on_dl_rq(&p->dl) && tsk_nr_cpus_allowed(p) > 1)
+ 		enqueue_pushable_dl_task(rq, p);
+ }
+ 
+@@ -1286,7 +1287,7 @@ static int find_later_rq(struct task_struct *task)
+ 	if (unlikely(!later_mask))
+ 		return -1;
+ 
+-	if (task->nr_cpus_allowed == 1)
++	if (tsk_nr_cpus_allowed(task) == 1)
+ 		return -1;
+ 
+ 	/*
+@@ -1392,7 +1393,7 @@ static struct rq *find_lock_later_rq(struct task_struct *task, struct rq *rq)
+ 		if (double_lock_balance(rq, later_rq)) {
+ 			if (unlikely(task_rq(task) != rq ||
+ 				     !cpumask_test_cpu(later_rq->cpu,
+-				                       &task->cpus_allowed) ||
++				                       tsk_cpus_allowed(task)) ||
+ 				     task_running(rq, task) ||
+ 				     !dl_task(task) ||
+ 				     !task_on_rq_queued(task))) {
+@@ -1432,7 +1433,7 @@ static struct task_struct *pick_next_pushable_dl_task(struct rq *rq)
+ 
+ 	BUG_ON(rq->cpu != task_cpu(p));
+ 	BUG_ON(task_current(rq, p));
+-	BUG_ON(p->nr_cpus_allowed <= 1);
++	BUG_ON(tsk_nr_cpus_allowed(p) <= 1);
+ 
+ 	BUG_ON(!task_on_rq_queued(p));
+ 	BUG_ON(!dl_task(p));
+@@ -1471,7 +1472,7 @@ static int push_dl_task(struct rq *rq)
+ 	 */
+ 	if (dl_task(rq->curr) &&
+ 	    dl_time_before(next_task->dl.deadline, rq->curr->dl.deadline) &&
+-	    rq->curr->nr_cpus_allowed > 1) {
++	    tsk_nr_cpus_allowed(rq->curr) > 1) {
+ 		resched_curr(rq);
+ 		return 0;
+ 	}
+@@ -1618,9 +1619,9 @@ static void task_woken_dl(struct rq *rq, struct task_struct *p)
+ {
+ 	if (!task_running(rq, p) &&
+ 	    !test_tsk_need_resched(rq->curr) &&
+-	    p->nr_cpus_allowed > 1 &&
++	    tsk_nr_cpus_allowed(p) > 1 &&
+ 	    dl_task(rq->curr) &&
+-	    (rq->curr->nr_cpus_allowed < 2 ||
++	    (tsk_nr_cpus_allowed(rq->curr) < 2 ||
+ 	     !dl_entity_preempt(&p->dl, &rq->curr->dl))) {
+ 		push_dl_tasks(rq);
+ 	}
+@@ -1724,7 +1725,7 @@ static void switched_to_dl(struct rq *rq, struct task_struct *p)
+ 
+ 	if (task_on_rq_queued(p) && rq->curr != p) {
+ #ifdef CONFIG_SMP
+-		if (p->nr_cpus_allowed > 1 && rq->dl.overloaded)
++		if (tsk_nr_cpus_allowed(p) > 1 && rq->dl.overloaded)
+ 			queue_push_tasks(rq);
+ #else
+ 		if (dl_task(rq->curr))
+diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
+index 4fbc3bd5ff60..5503c1f4290a 100644
+--- a/kernel/sched/debug.c
++++ b/kernel/sched/debug.c
+@@ -559,6 +559,9 @@ void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq)
+ 	P(rt_throttled);
+ 	PN(rt_time);
+ 	PN(rt_runtime);
++#ifdef CONFIG_SMP
++	P(rt_nr_migratory);
++#endif
+ 
+ #undef PN
+ #undef P
+@@ -954,6 +957,10 @@ void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
+ #endif
+ 	P(policy);
+ 	P(prio);
++#ifdef CONFIG_PREEMPT_RT_FULL
++	P(migrate_disable);
++#endif
++	P(nr_cpus_allowed);
+ #undef PN
+ #undef __PN
+ #undef P
+diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
+index eeaf920f46b9..3b66683e5b3f 100644
+--- a/kernel/sched/fair.c
++++ b/kernel/sched/fair.c
+@@ -3335,7 +3335,7 @@ check_preempt_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr)
+ 	ideal_runtime = sched_slice(cfs_rq, curr);
+ 	delta_exec = curr->sum_exec_runtime - curr->prev_sum_exec_runtime;
+ 	if (delta_exec > ideal_runtime) {
+-		resched_curr(rq_of(cfs_rq));
++		resched_curr_lazy(rq_of(cfs_rq));
+ 		/*
+ 		 * The current task ran long enough, ensure it doesn't get
+ 		 * re-elected due to buddy favours.
+@@ -3359,7 +3359,7 @@ check_preempt_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr)
+ 		return;
+ 
+ 	if (delta > ideal_runtime)
+-		resched_curr(rq_of(cfs_rq));
++		resched_curr_lazy(rq_of(cfs_rq));
+ }
+ 
+ static void
+@@ -3504,7 +3504,7 @@ entity_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr, int queued)
+ 	 * validating it and just reschedule.
+ 	 */
+ 	if (queued) {
+-		resched_curr(rq_of(cfs_rq));
++		resched_curr_lazy(rq_of(cfs_rq));
+ 		return;
+ 	}
+ 	/*
+@@ -3686,7 +3686,7 @@ static void __account_cfs_rq_runtime(struct cfs_rq *cfs_rq, u64 delta_exec)
+ 	 * hierarchy can be throttled
+ 	 */
+ 	if (!assign_cfs_rq_runtime(cfs_rq) && likely(cfs_rq->curr))
+-		resched_curr(rq_of(cfs_rq));
++		resched_curr_lazy(rq_of(cfs_rq));
+ }
+ 
+ static __always_inline
+@@ -4298,7 +4298,7 @@ static void hrtick_start_fair(struct rq *rq, struct task_struct *p)
+ 
+ 		if (delta < 0) {
+ 			if (rq->curr == p)
+-				resched_curr(rq);
++				resched_curr_lazy(rq);
+ 			return;
+ 		}
+ 		hrtick_start(rq, delta);
+@@ -5438,7 +5438,7 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_
+ 	return;
+ 
+ preempt:
+-	resched_curr(rq);
++	resched_curr_lazy(rq);
+ 	/*
+ 	 * Only set the backward buddy when the current task is still
+ 	 * on the rq. This can happen when a wakeup gets interleaved
+@@ -8189,7 +8189,7 @@ static void task_fork_fair(struct task_struct *p)
+ 		 * 'current' within the tree based on its new key value.
+ 		 */
+ 		swap(curr->vruntime, se->vruntime);
+-		resched_curr(rq);
++		resched_curr_lazy(rq);
+ 	}
+ 
+ 	se->vruntime -= cfs_rq->min_vruntime;
+@@ -8214,7 +8214,7 @@ prio_changed_fair(struct rq *rq, struct task_struct *p, int oldprio)
+ 	 */
+ 	if (rq->curr == p) {
+ 		if (p->prio > oldprio)
+-			resched_curr(rq);
++			resched_curr_lazy(rq);
+ 	} else
+ 		check_preempt_curr(rq, p, 0);
+ }
+diff --git a/kernel/sched/features.h b/kernel/sched/features.h
+index 69631fa46c2f..6d28fcd08872 100644
+--- a/kernel/sched/features.h
++++ b/kernel/sched/features.h
+@@ -45,11 +45,19 @@ SCHED_FEAT(LB_BIAS, true)
+  */
+ SCHED_FEAT(NONTASK_CAPACITY, true)
+ 
++#ifdef CONFIG_PREEMPT_RT_FULL
++SCHED_FEAT(TTWU_QUEUE, false)
++# ifdef CONFIG_PREEMPT_LAZY
++SCHED_FEAT(PREEMPT_LAZY, true)
++# endif
++#else
++
+ /*
+  * Queue remote wakeups on the target CPU and process them
+  * using the scheduler IPI. Reduces rq->lock contention/bounces.
+  */
+ SCHED_FEAT(TTWU_QUEUE, true)
++#endif
+ 
+ #ifdef HAVE_RT_PUSH_IPI
+ /*
+diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
+index ec4f538d4396..f7b281059ddf 100644
+--- a/kernel/sched/rt.c
++++ b/kernel/sched/rt.c
+@@ -47,6 +47,7 @@ void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime)
+ 
+ 	hrtimer_init(&rt_b->rt_period_timer,
+ 			CLOCK_MONOTONIC, HRTIMER_MODE_REL);
++	rt_b->rt_period_timer.irqsafe = 1;
+ 	rt_b->rt_period_timer.function = sched_rt_period_timer;
+ }
+ 
+@@ -101,6 +102,7 @@ void init_rt_rq(struct rt_rq *rt_rq)
+ 	rt_rq->push_cpu = nr_cpu_ids;
+ 	raw_spin_lock_init(&rt_rq->push_lock);
+ 	init_irq_work(&rt_rq->push_work, push_irq_work_func);
++	rt_rq->push_work.flags |= IRQ_WORK_HARD_IRQ;
+ #endif
+ #endif /* CONFIG_SMP */
+ 	/* We start is dequeued state, because no RT tasks are queued */
+@@ -334,7 +336,7 @@ static void inc_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
+ 	rt_rq = &rq_of_rt_rq(rt_rq)->rt;
+ 
+ 	rt_rq->rt_nr_total++;
+-	if (p->nr_cpus_allowed > 1)
++	if (tsk_nr_cpus_allowed(p) > 1)
+ 		rt_rq->rt_nr_migratory++;
+ 
+ 	update_rt_migration(rt_rq);
+@@ -351,7 +353,7 @@ static void dec_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
+ 	rt_rq = &rq_of_rt_rq(rt_rq)->rt;
+ 
+ 	rt_rq->rt_nr_total--;
+-	if (p->nr_cpus_allowed > 1)
++	if (tsk_nr_cpus_allowed(p) > 1)
+ 		rt_rq->rt_nr_migratory--;
+ 
+ 	update_rt_migration(rt_rq);
+@@ -1324,7 +1326,7 @@ enqueue_task_rt(struct rq *rq, struct task_struct *p, int flags)
+ 
+ 	enqueue_rt_entity(rt_se, flags);
+ 
+-	if (!task_current(rq, p) && p->nr_cpus_allowed > 1)
++	if (!task_current(rq, p) && tsk_nr_cpus_allowed(p) > 1)
+ 		enqueue_pushable_task(rq, p);
+ }
+ 
+@@ -1413,7 +1415,7 @@ select_task_rq_rt(struct task_struct *p, int cpu, int sd_flag, int flags)
+ 	 * will have to sort it out.
+ 	 */
+ 	if (curr && unlikely(rt_task(curr)) &&
+-	    (curr->nr_cpus_allowed < 2 ||
++	    (tsk_nr_cpus_allowed(curr) < 2 ||
+ 	     curr->prio <= p->prio)) {
+ 		int target = find_lowest_rq(p);
+ 
+@@ -1437,7 +1439,7 @@ static void check_preempt_equal_prio(struct rq *rq, struct task_struct *p)
+ 	 * Current can't be migrated, useless to reschedule,
+ 	 * let's hope p can move out.
+ 	 */
+-	if (rq->curr->nr_cpus_allowed == 1 ||
++	if (tsk_nr_cpus_allowed(rq->curr) == 1 ||
+ 	    !cpupri_find(&rq->rd->cpupri, rq->curr, NULL))
+ 		return;
+ 
+@@ -1445,7 +1447,7 @@ static void check_preempt_equal_prio(struct rq *rq, struct task_struct *p)
+ 	 * p is migratable, so let's not schedule it and
+ 	 * see if it is pushed or pulled somewhere else.
+ 	 */
+-	if (p->nr_cpus_allowed != 1
++	if (tsk_nr_cpus_allowed(p) != 1
+ 	    && cpupri_find(&rq->rd->cpupri, p, NULL))
+ 		return;
+ 
+@@ -1579,7 +1581,7 @@ static void put_prev_task_rt(struct rq *rq, struct task_struct *p)
+ 	 * The previous task needs to be made eligible for pushing
+ 	 * if it is still active
+ 	 */
+-	if (on_rt_rq(&p->rt) && p->nr_cpus_allowed > 1)
++	if (on_rt_rq(&p->rt) && tsk_nr_cpus_allowed(p) > 1)
+ 		enqueue_pushable_task(rq, p);
+ }
+ 
+@@ -1629,7 +1631,7 @@ static int find_lowest_rq(struct task_struct *task)
+ 	if (unlikely(!lowest_mask))
+ 		return -1;
+ 
+-	if (task->nr_cpus_allowed == 1)
++	if (tsk_nr_cpus_allowed(task) == 1)
+ 		return -1; /* No other targets possible */
+ 
+ 	if (!cpupri_find(&task_rq(task)->rd->cpupri, task, lowest_mask))
+@@ -1762,7 +1764,7 @@ static struct task_struct *pick_next_pushable_task(struct rq *rq)
+ 
+ 	BUG_ON(rq->cpu != task_cpu(p));
+ 	BUG_ON(task_current(rq, p));
+-	BUG_ON(p->nr_cpus_allowed <= 1);
++	BUG_ON(tsk_nr_cpus_allowed(p) <= 1);
+ 
+ 	BUG_ON(!task_on_rq_queued(p));
+ 	BUG_ON(!rt_task(p));
+@@ -2122,9 +2124,9 @@ static void task_woken_rt(struct rq *rq, struct task_struct *p)
+ {
+ 	if (!task_running(rq, p) &&
+ 	    !test_tsk_need_resched(rq->curr) &&
+-	    p->nr_cpus_allowed > 1 &&
++	    tsk_nr_cpus_allowed(p) > 1 &&
+ 	    (dl_task(rq->curr) || rt_task(rq->curr)) &&
+-	    (rq->curr->nr_cpus_allowed < 2 ||
++	    (tsk_nr_cpus_allowed(rq->curr) < 2 ||
+ 	     rq->curr->prio <= p->prio))
+ 		push_rt_tasks(rq);
+ }
+@@ -2197,7 +2199,7 @@ static void switched_to_rt(struct rq *rq, struct task_struct *p)
+ 	 */
+ 	if (task_on_rq_queued(p) && rq->curr != p) {
+ #ifdef CONFIG_SMP
+-		if (p->nr_cpus_allowed > 1 && rq->rt.overloaded)
++		if (tsk_nr_cpus_allowed(p) > 1 && rq->rt.overloaded)
+ 			queue_push_tasks(rq);
+ #else
+ 		if (p->prio < rq->curr->prio)
+diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
+index ec2e8d23527e..93c999cbe58f 100644
+--- a/kernel/sched/sched.h
++++ b/kernel/sched/sched.h
+@@ -1128,6 +1128,7 @@ static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
+ #define WF_SYNC		0x01		/* waker goes to sleep after wakeup */
+ #define WF_FORK		0x02		/* child wakeup after fork */
+ #define WF_MIGRATED	0x4		/* internal use, task got migrated */
++#define WF_LOCK_SLEEPER	0x08		/* wakeup spinlock "sleeper" */
+ 
+ /*
+  * To aid in avoiding the subversion of "niceness" due to uneven distribution
+@@ -1303,6 +1304,15 @@ extern void init_sched_fair_class(void);
+ extern void resched_curr(struct rq *rq);
+ extern void resched_cpu(int cpu);
+ 
++#ifdef CONFIG_PREEMPT_LAZY
++extern void resched_curr_lazy(struct rq *rq);
++#else
++static inline void resched_curr_lazy(struct rq *rq)
++{
++	resched_curr(rq);
++}
++#endif
++
+ extern struct rt_bandwidth def_rt_bandwidth;
+ extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
+ 
+diff --git a/kernel/sched/swait.c b/kernel/sched/swait.c
+index 82f0dff90030..e2e224c59c0a 100644
+--- a/kernel/sched/swait.c
++++ b/kernel/sched/swait.c
+@@ -1,5 +1,6 @@
+ #include <linux/sched.h>
+ #include <linux/swait.h>
++#include <linux/suspend.h>
+ 
+ void __init_swait_queue_head(struct swait_queue_head *q, const char *name,
+ 			     struct lock_class_key *key)
+@@ -29,6 +30,25 @@ void swake_up_locked(struct swait_queue_head *q)
+ }
+ EXPORT_SYMBOL(swake_up_locked);
+ 
++void swake_up_all_locked(struct swait_queue_head *q)
++{
++	struct swait_queue *curr;
++	int wakes = 0;
++
++	while (!list_empty(&q->task_list)) {
++
++		curr = list_first_entry(&q->task_list, typeof(*curr),
++					task_list);
++		wake_up_process(curr->task);
++		list_del_init(&curr->task_list);
++		wakes++;
++	}
++	if (pm_in_action)
++		return;
++	WARN(wakes > 2, "complete_all() with %d waiters\n", wakes);
++}
++EXPORT_SYMBOL(swake_up_all_locked);
++
+ void swake_up(struct swait_queue_head *q)
+ {
+ 	unsigned long flags;
+diff --git a/kernel/sched/swork.c b/kernel/sched/swork.c
+new file mode 100644
+index 000000000000..1950f40ca725
+--- /dev/null
++++ b/kernel/sched/swork.c
+@@ -0,0 +1,173 @@
++/*
++ * Copyright (C) 2014 BMW Car IT GmbH, Daniel Wagner daniel.wagner@bmw-carit.de
++ *
++ * Provides a framework for enqueuing callbacks from irq context
++ * PREEMPT_RT_FULL safe. The callbacks are executed in kthread context.
++ */
++
++#include <linux/swait.h>
++#include <linux/swork.h>
++#include <linux/kthread.h>
++#include <linux/slab.h>
++#include <linux/spinlock.h>
++#include <linux/export.h>
++
++#define SWORK_EVENT_PENDING     (1 << 0)
++
++static DEFINE_MUTEX(worker_mutex);
++static struct sworker *glob_worker;
++
++struct sworker {
++	struct list_head events;
++	struct swait_queue_head wq;
++
++	raw_spinlock_t lock;
++
++	struct task_struct *task;
++	int refs;
++};
++
++static bool swork_readable(struct sworker *worker)
++{
++	bool r;
++
++	if (kthread_should_stop())
++		return true;
++
++	raw_spin_lock_irq(&worker->lock);
++	r = !list_empty(&worker->events);
++	raw_spin_unlock_irq(&worker->lock);
++
++	return r;
++}
++
++static int swork_kthread(void *arg)
++{
++	struct sworker *worker = arg;
++
++	for (;;) {
++		swait_event_interruptible(worker->wq,
++					swork_readable(worker));
++		if (kthread_should_stop())
++			break;
++
++		raw_spin_lock_irq(&worker->lock);
++		while (!list_empty(&worker->events)) {
++			struct swork_event *sev;
++
++			sev = list_first_entry(&worker->events,
++					struct swork_event, item);
++			list_del(&sev->item);
++			raw_spin_unlock_irq(&worker->lock);
++
++			WARN_ON_ONCE(!test_and_clear_bit(SWORK_EVENT_PENDING,
++							 &sev->flags));
++			sev->func(sev);
++			raw_spin_lock_irq(&worker->lock);
++		}
++		raw_spin_unlock_irq(&worker->lock);
++	}
++	return 0;
++}
++
++static struct sworker *swork_create(void)
++{
++	struct sworker *worker;
++
++	worker = kzalloc(sizeof(*worker), GFP_KERNEL);
++	if (!worker)
++		return ERR_PTR(-ENOMEM);
++
++	INIT_LIST_HEAD(&worker->events);
++	raw_spin_lock_init(&worker->lock);
++	init_swait_queue_head(&worker->wq);
++
++	worker->task = kthread_run(swork_kthread, worker, "kswork");
++	if (IS_ERR(worker->task)) {
++		kfree(worker);
++		return ERR_PTR(-ENOMEM);
++	}
++
++	return worker;
++}
++
++static void swork_destroy(struct sworker *worker)
++{
++	kthread_stop(worker->task);
++
++	WARN_ON(!list_empty(&worker->events));
++	kfree(worker);
++}
++
++/**
++ * swork_queue - queue swork
++ *
++ * Returns %false if @work was already on a queue, %true otherwise.
++ *
++ * The work is queued and processed on a random CPU
++ */
++bool swork_queue(struct swork_event *sev)
++{
++	unsigned long flags;
++
++	if (test_and_set_bit(SWORK_EVENT_PENDING, &sev->flags))
++		return false;
++
++	raw_spin_lock_irqsave(&glob_worker->lock, flags);
++	list_add_tail(&sev->item, &glob_worker->events);
++	raw_spin_unlock_irqrestore(&glob_worker->lock, flags);
++
++	swake_up(&glob_worker->wq);
++	return true;
++}
++EXPORT_SYMBOL_GPL(swork_queue);
++
++/**
++ * swork_get - get an instance of the sworker
++ *
++ * Returns an negative error code if the initialization if the worker did not
++ * work, %0 otherwise.
++ *
++ */
++int swork_get(void)
++{
++	struct sworker *worker;
++
++	mutex_lock(&worker_mutex);
++	if (!glob_worker) {
++		worker = swork_create();
++		if (IS_ERR(worker)) {
++			mutex_unlock(&worker_mutex);
++			return -ENOMEM;
++		}
++
++		glob_worker = worker;
++	}
++
++	glob_worker->refs++;
++	mutex_unlock(&worker_mutex);
++
++	return 0;
++}
++EXPORT_SYMBOL_GPL(swork_get);
++
++/**
++ * swork_put - puts an instance of the sworker
++ *
++ * Will destroy the sworker thread. This function must not be called until all
++ * queued events have been completed.
++ */
++void swork_put(void)
++{
++	mutex_lock(&worker_mutex);
++
++	glob_worker->refs--;
++	if (glob_worker->refs > 0)
++		goto out;
++
++	swork_destroy(glob_worker);
++	glob_worker = NULL;
++out:
++	mutex_unlock(&worker_mutex);
++}
++EXPORT_SYMBOL_GPL(swork_put);
+diff --git a/kernel/signal.c b/kernel/signal.c
+index aa9bf00749c1..0a625c7b8792 100644
+--- a/kernel/signal.c
++++ b/kernel/signal.c
+@@ -14,6 +14,7 @@
+ #include <linux/export.h>
+ #include <linux/init.h>
+ #include <linux/sched.h>
++#include <linux/sched/rt.h>
+ #include <linux/fs.h>
+ #include <linux/tty.h>
+ #include <linux/binfmts.h>
+@@ -352,13 +353,30 @@ static bool task_participate_group_stop(struct task_struct *task)
+ 	return false;
+ }
+ 
++static inline struct sigqueue *get_task_cache(struct task_struct *t)
++{
++	struct sigqueue *q = t->sigqueue_cache;
++
++	if (cmpxchg(&t->sigqueue_cache, q, NULL) != q)
++		return NULL;
++	return q;
++}
++
++static inline int put_task_cache(struct task_struct *t, struct sigqueue *q)
++{
++	if (cmpxchg(&t->sigqueue_cache, NULL, q) == NULL)
++		return 0;
++	return 1;
++}
++
+ /*
+  * allocate a new signal queue record
+  * - this may be called without locks if and only if t == current, otherwise an
+  *   appropriate lock must be held to stop the target task from exiting
+  */
+ static struct sigqueue *
+-__sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimit)
++__sigqueue_do_alloc(int sig, struct task_struct *t, gfp_t flags,
++		    int override_rlimit, int fromslab)
+ {
+ 	struct sigqueue *q = NULL;
+ 	struct user_struct *user;
+@@ -375,7 +393,10 @@ __sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimi
+ 	if (override_rlimit ||
+ 	    atomic_read(&user->sigpending) <=
+ 			task_rlimit(t, RLIMIT_SIGPENDING)) {
+-		q = kmem_cache_alloc(sigqueue_cachep, flags);
++		if (!fromslab)
++			q = get_task_cache(t);
++		if (!q)
++			q = kmem_cache_alloc(sigqueue_cachep, flags);
+ 	} else {
+ 		print_dropped_signal(sig);
+ 	}
+@@ -392,6 +413,13 @@ __sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimi
+ 	return q;
+ }
+ 
++static struct sigqueue *
++__sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags,
++		 int override_rlimit)
++{
++	return __sigqueue_do_alloc(sig, t, flags, override_rlimit, 0);
++}
++
+ static void __sigqueue_free(struct sigqueue *q)
+ {
+ 	if (q->flags & SIGQUEUE_PREALLOC)
+@@ -401,6 +429,21 @@ static void __sigqueue_free(struct sigqueue *q)
+ 	kmem_cache_free(sigqueue_cachep, q);
+ }
+ 
++static void sigqueue_free_current(struct sigqueue *q)
++{
++	struct user_struct *up;
++
++	if (q->flags & SIGQUEUE_PREALLOC)
++		return;
++
++	up = q->user;
++	if (rt_prio(current->normal_prio) && !put_task_cache(current, q)) {
++		atomic_dec(&up->sigpending);
++		free_uid(up);
++	} else
++		  __sigqueue_free(q);
++}
++
+ void flush_sigqueue(struct sigpending *queue)
+ {
+ 	struct sigqueue *q;
+@@ -414,6 +457,21 @@ void flush_sigqueue(struct sigpending *queue)
+ }
+ 
+ /*
++ * Called from __exit_signal. Flush tsk->pending and
++ * tsk->sigqueue_cache
++ */
++void flush_task_sigqueue(struct task_struct *tsk)
++{
++	struct sigqueue *q;
++
++	flush_sigqueue(&tsk->pending);
++
++	q = get_task_cache(tsk);
++	if (q)
++		kmem_cache_free(sigqueue_cachep, q);
++}
++
++/*
+  * Flush all pending signals for this kthread.
+  */
+ void flush_signals(struct task_struct *t)
+@@ -525,7 +583,7 @@ static void collect_signal(int sig, struct sigpending *list, siginfo_t *info)
+ still_pending:
+ 		list_del_init(&first->list);
+ 		copy_siginfo(info, &first->info);
+-		__sigqueue_free(first);
++		sigqueue_free_current(first);
+ 	} else {
+ 		/*
+ 		 * Ok, it wasn't in the queue.  This must be
+@@ -560,6 +618,8 @@ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
+ {
+ 	int signr;
+ 
++	WARN_ON_ONCE(tsk != current);
++
+ 	/* We only dequeue private signals from ourselves, we don't let
+ 	 * signalfd steal them
+ 	 */
+@@ -1156,8 +1216,8 @@ int do_send_sig_info(int sig, struct siginfo *info, struct task_struct *p,
+  * We don't want to have recursive SIGSEGV's etc, for example,
+  * that is why we also clear SIGNAL_UNKILLABLE.
+  */
+-int
+-force_sig_info(int sig, struct siginfo *info, struct task_struct *t)
++static int
++do_force_sig_info(int sig, struct siginfo *info, struct task_struct *t)
+ {
+ 	unsigned long int flags;
+ 	int ret, blocked, ignored;
+@@ -1182,6 +1242,39 @@ force_sig_info(int sig, struct siginfo *info, struct task_struct *t)
+ 	return ret;
+ }
+ 
++int force_sig_info(int sig, struct siginfo *info, struct task_struct *t)
++{
++/*
++ * On some archs, PREEMPT_RT has to delay sending a signal from a trap
++ * since it can not enable preemption, and the signal code's spin_locks
++ * turn into mutexes. Instead, it must set TIF_NOTIFY_RESUME which will
++ * send the signal on exit of the trap.
++ */
++#ifdef ARCH_RT_DELAYS_SIGNAL_SEND
++	if (in_atomic()) {
++		if (WARN_ON_ONCE(t != current))
++			return 0;
++		if (WARN_ON_ONCE(t->forced_info.si_signo))
++			return 0;
++
++		if (is_si_special(info)) {
++			WARN_ON_ONCE(info != SEND_SIG_PRIV);
++			t->forced_info.si_signo = sig;
++			t->forced_info.si_errno = 0;
++			t->forced_info.si_code = SI_KERNEL;
++			t->forced_info.si_pid = 0;
++			t->forced_info.si_uid = 0;
++		} else {
++			t->forced_info = *info;
++		}
++
++		set_tsk_thread_flag(t, TIF_NOTIFY_RESUME);
++		return 0;
++	}
++#endif
++	return do_force_sig_info(sig, info, t);
++}
++
+ /*
+  * Nuke all other threads in the group.
+  */
+@@ -1216,12 +1309,12 @@ struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
+ 		 * Disable interrupts early to avoid deadlocks.
+ 		 * See rcu_read_unlock() comment header for details.
+ 		 */
+-		local_irq_save(*flags);
++		local_irq_save_nort(*flags);
+ 		rcu_read_lock();
+ 		sighand = rcu_dereference(tsk->sighand);
+ 		if (unlikely(sighand == NULL)) {
+ 			rcu_read_unlock();
+-			local_irq_restore(*flags);
++			local_irq_restore_nort(*flags);
+ 			break;
+ 		}
+ 		/*
+@@ -1242,7 +1335,7 @@ struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
+ 		}
+ 		spin_unlock(&sighand->siglock);
+ 		rcu_read_unlock();
+-		local_irq_restore(*flags);
++		local_irq_restore_nort(*flags);
+ 	}
+ 
+ 	return sighand;
+@@ -1485,7 +1578,8 @@ EXPORT_SYMBOL(kill_pid);
+  */
+ struct sigqueue *sigqueue_alloc(void)
+ {
+-	struct sigqueue *q = __sigqueue_alloc(-1, current, GFP_KERNEL, 0);
++	/* Preallocated sigqueue objects always from the slabcache ! */
++	struct sigqueue *q = __sigqueue_do_alloc(-1, current, GFP_KERNEL, 0, 1);
+ 
+ 	if (q)
+ 		q->flags |= SIGQUEUE_PREALLOC;
+@@ -1846,15 +1940,7 @@ static void ptrace_stop(int exit_code, int why, int clear_code, siginfo_t *info)
+ 		if (gstop_done && ptrace_reparented(current))
+ 			do_notify_parent_cldstop(current, false, why);
+ 
+-		/*
+-		 * Don't want to allow preemption here, because
+-		 * sys_ptrace() needs this task to be inactive.
+-		 *
+-		 * XXX: implement read_unlock_no_resched().
+-		 */
+-		preempt_disable();
+ 		read_unlock(&tasklist_lock);
+-		preempt_enable_no_resched();
+ 		freezable_schedule();
+ 	} else {
+ 		/*
+@@ -2751,23 +2837,18 @@ int copy_siginfo_to_user(siginfo_t __user *to, const siginfo_t *from)
+  *  @ts: upper bound on process time suspension
+  */
+ int do_sigtimedwait(const sigset_t *which, siginfo_t *info,
+-			const struct timespec *ts)
++		    const struct timespec *ts)
+ {
++	ktime_t *to = NULL, timeout = { .tv64 = KTIME_MAX };
+ 	struct task_struct *tsk = current;
+-	long timeout = MAX_SCHEDULE_TIMEOUT;
+ 	sigset_t mask = *which;
+-	int sig;
++	int sig, ret = 0;
+ 
+ 	if (ts) {
+ 		if (!timespec_valid(ts))
+ 			return -EINVAL;
+-		timeout = timespec_to_jiffies(ts);
+-		/*
+-		 * We can be close to the next tick, add another one
+-		 * to ensure we will wait at least the time asked for.
+-		 */
+-		if (ts->tv_sec || ts->tv_nsec)
+-			timeout++;
++		timeout = timespec_to_ktime(*ts);
++		to = &timeout;
+ 	}
+ 
+ 	/*
+@@ -2778,7 +2859,7 @@ int do_sigtimedwait(const sigset_t *which, siginfo_t *info,
+ 
+ 	spin_lock_irq(&tsk->sighand->siglock);
+ 	sig = dequeue_signal(tsk, &mask, info);
+-	if (!sig && timeout) {
++	if (!sig && timeout.tv64) {
+ 		/*
+ 		 * None ready, temporarily unblock those we're interested
+ 		 * while we are sleeping in so that we'll be awakened when
+@@ -2790,8 +2871,9 @@ int do_sigtimedwait(const sigset_t *which, siginfo_t *info,
+ 		recalc_sigpending();
+ 		spin_unlock_irq(&tsk->sighand->siglock);
+ 
+-		timeout = freezable_schedule_timeout_interruptible(timeout);
+-
++		__set_current_state(TASK_INTERRUPTIBLE);
++		ret = freezable_schedule_hrtimeout_range(to, tsk->timer_slack_ns,
++							 HRTIMER_MODE_REL);
+ 		spin_lock_irq(&tsk->sighand->siglock);
+ 		__set_task_blocked(tsk, &tsk->real_blocked);
+ 		sigemptyset(&tsk->real_blocked);
+@@ -2801,7 +2883,7 @@ int do_sigtimedwait(const sigset_t *which, siginfo_t *info,
+ 
+ 	if (sig)
+ 		return sig;
+-	return timeout ? -EINTR : -EAGAIN;
++	return ret ? -EINTR : -EAGAIN;
+ }
+ 
+ /**
+diff --git a/kernel/softirq.c b/kernel/softirq.c
+index 17caf4b63342..a602b7152de7 100644
+--- a/kernel/softirq.c
++++ b/kernel/softirq.c
+@@ -21,10 +21,12 @@
+ #include <linux/freezer.h>
+ #include <linux/kthread.h>
+ #include <linux/rcupdate.h>
++#include <linux/delay.h>
+ #include <linux/ftrace.h>
+ #include <linux/smp.h>
+ #include <linux/smpboot.h>
+ #include <linux/tick.h>
++#include <linux/locallock.h>
+ #include <linux/irq.h>
+ 
+ #define CREATE_TRACE_POINTS
+@@ -56,12 +58,108 @@ EXPORT_SYMBOL(irq_stat);
+ static struct softirq_action softirq_vec[NR_SOFTIRQS] __cacheline_aligned_in_smp;
+ 
+ DEFINE_PER_CPU(struct task_struct *, ksoftirqd);
++#ifdef CONFIG_PREEMPT_RT_FULL
++#define TIMER_SOFTIRQS	((1 << TIMER_SOFTIRQ) | (1 << HRTIMER_SOFTIRQ))
++DEFINE_PER_CPU(struct task_struct *, ktimer_softirqd);
++#endif
+ 
+ const char * const softirq_to_name[NR_SOFTIRQS] = {
+ 	"HI", "TIMER", "NET_TX", "NET_RX", "BLOCK", "BLOCK_IOPOLL",
+ 	"TASKLET", "SCHED", "HRTIMER", "RCU"
+ };
+ 
++#ifdef CONFIG_NO_HZ_COMMON
++# ifdef CONFIG_PREEMPT_RT_FULL
++
++struct softirq_runner {
++	struct task_struct *runner[NR_SOFTIRQS];
++};
++
++static DEFINE_PER_CPU(struct softirq_runner, softirq_runners);
++
++static inline void softirq_set_runner(unsigned int sirq)
++{
++	struct softirq_runner *sr = this_cpu_ptr(&softirq_runners);
++
++	sr->runner[sirq] = current;
++}
++
++static inline void softirq_clr_runner(unsigned int sirq)
++{
++	struct softirq_runner *sr = this_cpu_ptr(&softirq_runners);
++
++	sr->runner[sirq] = NULL;
++}
++
++/*
++ * On preempt-rt a softirq running context might be blocked on a
++ * lock. There might be no other runnable task on this CPU because the
++ * lock owner runs on some other CPU. So we have to go into idle with
++ * the pending bit set. Therefor we need to check this otherwise we
++ * warn about false positives which confuses users and defeats the
++ * whole purpose of this test.
++ *
++ * This code is called with interrupts disabled.
++ */
++void softirq_check_pending_idle(void)
++{
++	static int rate_limit;
++	struct softirq_runner *sr = this_cpu_ptr(&softirq_runners);
++	u32 warnpending;
++	int i;
++
++	if (rate_limit >= 10)
++		return;
++
++	warnpending = local_softirq_pending() & SOFTIRQ_STOP_IDLE_MASK;
++	for (i = 0; i < NR_SOFTIRQS; i++) {
++		struct task_struct *tsk = sr->runner[i];
++
++		/*
++		 * The wakeup code in rtmutex.c wakes up the task
++		 * _before_ it sets pi_blocked_on to NULL under
++		 * tsk->pi_lock. So we need to check for both: state
++		 * and pi_blocked_on.
++		 */
++		if (tsk) {
++			raw_spin_lock(&tsk->pi_lock);
++			if (tsk->pi_blocked_on || tsk->state == TASK_RUNNING) {
++				/* Clear all bits pending in that task */
++				warnpending &= ~(tsk->softirqs_raised);
++				warnpending &= ~(1 << i);
++			}
++			raw_spin_unlock(&tsk->pi_lock);
++		}
++	}
++
++	if (warnpending) {
++		printk(KERN_ERR "NOHZ: local_softirq_pending %02x\n",
++		       warnpending);
++		rate_limit++;
++	}
++}
++# else
++/*
++ * On !PREEMPT_RT we just printk rate limited:
++ */
++void softirq_check_pending_idle(void)
++{
++	static int rate_limit;
++
++	if (rate_limit < 10 &&
++			(local_softirq_pending() & SOFTIRQ_STOP_IDLE_MASK)) {
++		printk(KERN_ERR "NOHZ: local_softirq_pending %02x\n",
++		       local_softirq_pending());
++		rate_limit++;
++	}
++}
++# endif
++
++#else /* !CONFIG_NO_HZ_COMMON */
++static inline void softirq_set_runner(unsigned int sirq) { }
++static inline void softirq_clr_runner(unsigned int sirq) { }
++#endif
++
+ /*
+  * we cannot loop indefinitely here to avoid userspace starvation,
+  * but we also don't want to introduce a worst case 1/HZ latency
+@@ -77,6 +175,79 @@ static void wakeup_softirqd(void)
+ 		wake_up_process(tsk);
+ }
+ 
++#ifdef CONFIG_PREEMPT_RT_FULL
++static void wakeup_timer_softirqd(void)
++{
++	/* Interrupts are disabled: no need to stop preemption */
++	struct task_struct *tsk = __this_cpu_read(ktimer_softirqd);
++
++	if (tsk && tsk->state != TASK_RUNNING)
++		wake_up_process(tsk);
++}
++#endif
++
++static void handle_softirq(unsigned int vec_nr)
++{
++	struct softirq_action *h = softirq_vec + vec_nr;
++	int prev_count;
++
++	prev_count = preempt_count();
++
++	kstat_incr_softirqs_this_cpu(vec_nr);
++
++	trace_softirq_entry(vec_nr);
++	h->action(h);
++	trace_softirq_exit(vec_nr);
++	if (unlikely(prev_count != preempt_count())) {
++		pr_err("huh, entered softirq %u %s %p with preempt_count %08x, exited with %08x?\n",
++		       vec_nr, softirq_to_name[vec_nr], h->action,
++		       prev_count, preempt_count());
++		preempt_count_set(prev_count);
++	}
++}
++
++#ifndef CONFIG_PREEMPT_RT_FULL
++static inline int ksoftirqd_softirq_pending(void)
++{
++	return local_softirq_pending();
++}
++
++static void handle_pending_softirqs(u32 pending)
++{
++	struct softirq_action *h = softirq_vec;
++	int softirq_bit;
++
++	local_irq_enable();
++
++	h = softirq_vec;
++
++	while ((softirq_bit = ffs(pending))) {
++		unsigned int vec_nr;
++
++		h += softirq_bit - 1;
++		vec_nr = h - softirq_vec;
++		handle_softirq(vec_nr);
++
++		h++;
++		pending >>= softirq_bit;
++	}
++
++	rcu_bh_qs();
++	local_irq_disable();
++}
++
++static void run_ksoftirqd(unsigned int cpu)
++{
++	local_irq_disable();
++	if (ksoftirqd_softirq_pending()) {
++		__do_softirq();
++		local_irq_enable();
++		cond_resched_rcu_qs();
++		return;
++	}
++	local_irq_enable();
++}
++
+ /*
+  * preempt_count and SOFTIRQ_OFFSET usage:
+  * - preempt_count is changed by SOFTIRQ_OFFSET on entering or leaving
+@@ -232,10 +403,8 @@ asmlinkage __visible void __softirq_entry __do_softirq(void)
+ 	unsigned long end = jiffies + MAX_SOFTIRQ_TIME;
+ 	unsigned long old_flags = current->flags;
+ 	int max_restart = MAX_SOFTIRQ_RESTART;
+-	struct softirq_action *h;
+ 	bool in_hardirq;
+ 	__u32 pending;
+-	int softirq_bit;
+ 
+ 	/*
+ 	 * Mask out PF_MEMALLOC s current task context is borrowed for the
+@@ -254,36 +423,7 @@ asmlinkage __visible void __softirq_entry __do_softirq(void)
+ 	/* Reset the pending bitmask before enabling irqs */
+ 	set_softirq_pending(0);
+ 
+-	local_irq_enable();
+-
+-	h = softirq_vec;
+-
+-	while ((softirq_bit = ffs(pending))) {
+-		unsigned int vec_nr;
+-		int prev_count;
+-
+-		h += softirq_bit - 1;
+-
+-		vec_nr = h - softirq_vec;
+-		prev_count = preempt_count();
+-
+-		kstat_incr_softirqs_this_cpu(vec_nr);
+-
+-		trace_softirq_entry(vec_nr);
+-		h->action(h);
+-		trace_softirq_exit(vec_nr);
+-		if (unlikely(prev_count != preempt_count())) {
+-			pr_err("huh, entered softirq %u %s %p with preempt_count %08x, exited with %08x?\n",
+-			       vec_nr, softirq_to_name[vec_nr], h->action,
+-			       prev_count, preempt_count());
+-			preempt_count_set(prev_count);
+-		}
+-		h++;
+-		pending >>= softirq_bit;
+-	}
+-
+-	rcu_bh_qs();
+-	local_irq_disable();
++	handle_pending_softirqs(pending);
+ 
+ 	pending = local_softirq_pending();
+ 	if (pending) {
+@@ -320,6 +460,310 @@ asmlinkage __visible void do_softirq(void)
+ }
+ 
+ /*
++ * This function must run with irqs disabled!
++ */
++void raise_softirq_irqoff(unsigned int nr)
++{
++	__raise_softirq_irqoff(nr);
++
++	/*
++	 * If we're in an interrupt or softirq, we're done
++	 * (this also catches softirq-disabled code). We will
++	 * actually run the softirq once we return from
++	 * the irq or softirq.
++	 *
++	 * Otherwise we wake up ksoftirqd to make sure we
++	 * schedule the softirq soon.
++	 */
++	if (!in_interrupt())
++		wakeup_softirqd();
++}
++
++void __raise_softirq_irqoff(unsigned int nr)
++{
++	trace_softirq_raise(nr);
++	or_softirq_pending(1UL << nr);
++}
++
++static inline void local_bh_disable_nort(void) { local_bh_disable(); }
++static inline void _local_bh_enable_nort(void) { _local_bh_enable(); }
++static void ksoftirqd_set_sched_params(unsigned int cpu) { }
++
++#else /* !PREEMPT_RT_FULL */
++
++/*
++ * On RT we serialize softirq execution with a cpu local lock per softirq
++ */
++static DEFINE_PER_CPU(struct local_irq_lock [NR_SOFTIRQS], local_softirq_locks);
++
++void __init softirq_early_init(void)
++{
++	int i;
++
++	for (i = 0; i < NR_SOFTIRQS; i++)
++		local_irq_lock_init(local_softirq_locks[i]);
++}
++
++static void lock_softirq(int which)
++{
++	local_lock(local_softirq_locks[which]);
++}
++
++static void unlock_softirq(int which)
++{
++	local_unlock(local_softirq_locks[which]);
++}
++
++static void do_single_softirq(int which)
++{
++	unsigned long old_flags = current->flags;
++
++	current->flags &= ~PF_MEMALLOC;
++	vtime_account_irq_enter(current);
++	current->flags |= PF_IN_SOFTIRQ;
++	lockdep_softirq_enter();
++	local_irq_enable();
++	handle_softirq(which);
++	local_irq_disable();
++	lockdep_softirq_exit();
++	current->flags &= ~PF_IN_SOFTIRQ;
++	vtime_account_irq_enter(current);
++	tsk_restore_flags(current, old_flags, PF_MEMALLOC);
++}
++
++/*
++ * Called with interrupts disabled. Process softirqs which were raised
++ * in current context (or on behalf of ksoftirqd).
++ */
++static void do_current_softirqs(void)
++{
++	while (current->softirqs_raised) {
++		int i = __ffs(current->softirqs_raised);
++		unsigned int pending, mask = (1U << i);
++
++		current->softirqs_raised &= ~mask;
++		local_irq_enable();
++
++		/*
++		 * If the lock is contended, we boost the owner to
++		 * process the softirq or leave the critical section
++		 * now.
++		 */
++		lock_softirq(i);
++		local_irq_disable();
++		softirq_set_runner(i);
++		/*
++		 * Check with the local_softirq_pending() bits,
++		 * whether we need to process this still or if someone
++		 * else took care of it.
++		 */
++		pending = local_softirq_pending();
++		if (pending & mask) {
++			set_softirq_pending(pending & ~mask);
++			do_single_softirq(i);
++		}
++		softirq_clr_runner(i);
++		WARN_ON(current->softirq_nestcnt != 1);
++		local_irq_enable();
++		unlock_softirq(i);
++		local_irq_disable();
++	}
++}
++
++void __local_bh_disable(void)
++{
++	if (++current->softirq_nestcnt == 1)
++		migrate_disable();
++}
++EXPORT_SYMBOL(__local_bh_disable);
++
++void __local_bh_enable(void)
++{
++	if (WARN_ON(current->softirq_nestcnt == 0))
++		return;
++
++	local_irq_disable();
++	if (current->softirq_nestcnt == 1 && current->softirqs_raised)
++		do_current_softirqs();
++	local_irq_enable();
++
++	if (--current->softirq_nestcnt == 0)
++		migrate_enable();
++}
++EXPORT_SYMBOL(__local_bh_enable);
++
++void _local_bh_enable(void)
++{
++	if (WARN_ON(current->softirq_nestcnt == 0))
++		return;
++	if (--current->softirq_nestcnt == 0)
++		migrate_enable();
++}
++EXPORT_SYMBOL(_local_bh_enable);
++
++int in_serving_softirq(void)
++{
++	return current->flags & PF_IN_SOFTIRQ;
++}
++EXPORT_SYMBOL(in_serving_softirq);
++
++/* Called with preemption disabled */
++static void run_ksoftirqd(unsigned int cpu)
++{
++	local_irq_disable();
++	current->softirq_nestcnt++;
++
++	do_current_softirqs();
++	current->softirq_nestcnt--;
++	local_irq_enable();
++	cond_resched_rcu_qs();
++}
++
++/*
++ * Called from netif_rx_ni(). Preemption enabled, but migration
++ * disabled. So the cpu can't go away under us.
++ */
++void thread_do_softirq(void)
++{
++	if (!in_serving_softirq() && current->softirqs_raised) {
++		current->softirq_nestcnt++;
++		do_current_softirqs();
++		current->softirq_nestcnt--;
++	}
++}
++
++static void do_raise_softirq_irqoff(unsigned int nr)
++{
++	unsigned int mask;
++
++	mask = 1UL << nr;
++
++	trace_softirq_raise(nr);
++	or_softirq_pending(mask);
++
++	/*
++	 * If we are not in a hard interrupt and inside a bh disabled
++	 * region, we simply raise the flag on current. local_bh_enable()
++	 * will make sure that the softirq is executed. Otherwise we
++	 * delegate it to ksoftirqd.
++	 */
++	if (!in_irq() && current->softirq_nestcnt)
++		current->softirqs_raised |= mask;
++	else if (!__this_cpu_read(ksoftirqd) || !__this_cpu_read(ktimer_softirqd))
++		return;
++
++	if (mask & TIMER_SOFTIRQS)
++		__this_cpu_read(ktimer_softirqd)->softirqs_raised |= mask;
++	else
++		__this_cpu_read(ksoftirqd)->softirqs_raised |= mask;
++}
++
++static void wakeup_proper_softirq(unsigned int nr)
++{
++	if ((1UL << nr) & TIMER_SOFTIRQS)
++		wakeup_timer_softirqd();
++	else
++		wakeup_softirqd();
++}
++
++
++void __raise_softirq_irqoff(unsigned int nr)
++{
++	do_raise_softirq_irqoff(nr);
++	if (!in_irq() && !current->softirq_nestcnt)
++		wakeup_proper_softirq(nr);
++}
++
++/*
++ * Same as __raise_softirq_irqoff() but will process them in ksoftirqd
++ */
++void __raise_softirq_irqoff_ksoft(unsigned int nr)
++{
++	unsigned int mask;
++
++	if (WARN_ON_ONCE(!__this_cpu_read(ksoftirqd) ||
++			 !__this_cpu_read(ktimer_softirqd)))
++		return;
++	mask = 1UL << nr;
++
++	trace_softirq_raise(nr);
++	or_softirq_pending(mask);
++	if (mask & TIMER_SOFTIRQS)
++		__this_cpu_read(ktimer_softirqd)->softirqs_raised |= mask;
++	else
++		__this_cpu_read(ksoftirqd)->softirqs_raised |= mask;
++	wakeup_proper_softirq(nr);
++}
++
++/*
++ * This function must run with irqs disabled!
++ */
++void raise_softirq_irqoff(unsigned int nr)
++{
++	do_raise_softirq_irqoff(nr);
++
++	/*
++	 * If we're in an hard interrupt we let irq return code deal
++	 * with the wakeup of ksoftirqd.
++	 */
++	if (in_irq())
++		return;
++	/*
++	 * If we are in thread context but outside of a bh disabled
++	 * region, we need to wake ksoftirqd as well.
++	 *
++	 * CHECKME: Some of the places which do that could be wrapped
++	 * into local_bh_disable/enable pairs. Though it's unclear
++	 * whether this is worth the effort. To find those places just
++	 * raise a WARN() if the condition is met.
++	 */
++	if (!current->softirq_nestcnt)
++		wakeup_proper_softirq(nr);
++}
++
++static inline int ksoftirqd_softirq_pending(void)
++{
++	return current->softirqs_raised;
++}
++
++static inline void local_bh_disable_nort(void) { }
++static inline void _local_bh_enable_nort(void) { }
++
++static inline void ksoftirqd_set_sched_params(unsigned int cpu)
++{
++	/* Take over all but timer pending softirqs when starting */
++	local_irq_disable();
++	current->softirqs_raised = local_softirq_pending() & ~TIMER_SOFTIRQS;
++	local_irq_enable();
++}
++
++static inline void ktimer_softirqd_set_sched_params(unsigned int cpu)
++{
++	struct sched_param param = { .sched_priority = 1 };
++
++	sched_setscheduler(current, SCHED_FIFO, &param);
++
++	/* Take over timer pending softirqs when starting */
++	local_irq_disable();
++	current->softirqs_raised = local_softirq_pending() & TIMER_SOFTIRQS;
++	local_irq_enable();
++}
++
++static inline void ktimer_softirqd_clr_sched_params(unsigned int cpu,
++						    bool online)
++{
++	struct sched_param param = { .sched_priority = 0 };
++
++	sched_setscheduler(current, SCHED_NORMAL, &param);
++}
++
++static int ktimer_softirqd_should_run(unsigned int cpu)
++{
++	return current->softirqs_raised;
++}
++
++#endif /* PREEMPT_RT_FULL */
++/*
+  * Enter an interrupt context.
+  */
+ void irq_enter(void)
+@@ -330,9 +774,9 @@ void irq_enter(void)
+ 		 * Prevent raise_softirq from needlessly waking up ksoftirqd
+ 		 * here, as softirq will be serviced on return from interrupt.
+ 		 */
+-		local_bh_disable();
++		local_bh_disable_nort();
+ 		tick_irq_enter();
+-		_local_bh_enable();
++		_local_bh_enable_nort();
+ 	}
+ 
+ 	__irq_enter();
+@@ -340,6 +784,7 @@ void irq_enter(void)
+ 
+ static inline void invoke_softirq(void)
+ {
++#ifndef CONFIG_PREEMPT_RT_FULL
+ 	if (!force_irqthreads) {
+ #ifdef CONFIG_HAVE_IRQ_EXIT_ON_IRQ_STACK
+ 		/*
+@@ -359,6 +804,18 @@ static inline void invoke_softirq(void)
+ 	} else {
+ 		wakeup_softirqd();
+ 	}
++#else /* PREEMPT_RT_FULL */
++	unsigned long flags;
++
++	local_irq_save(flags);
++	if (__this_cpu_read(ksoftirqd) &&
++			__this_cpu_read(ksoftirqd)->softirqs_raised)
++		wakeup_softirqd();
++	if (__this_cpu_read(ktimer_softirqd) &&
++			__this_cpu_read(ktimer_softirqd)->softirqs_raised)
++		wakeup_timer_softirqd();
++	local_irq_restore(flags);
++#endif
+ }
+ 
+ static inline void tick_irq_exit(void)
+@@ -395,26 +852,6 @@ void irq_exit(void)
+ 	trace_hardirq_exit(); /* must be last! */
+ }
+ 
+-/*
+- * This function must run with irqs disabled!
+- */
+-inline void raise_softirq_irqoff(unsigned int nr)
+-{
+-	__raise_softirq_irqoff(nr);
+-
+-	/*
+-	 * If we're in an interrupt or softirq, we're done
+-	 * (this also catches softirq-disabled code). We will
+-	 * actually run the softirq once we return from
+-	 * the irq or softirq.
+-	 *
+-	 * Otherwise we wake up ksoftirqd to make sure we
+-	 * schedule the softirq soon.
+-	 */
+-	if (!in_interrupt())
+-		wakeup_softirqd();
+-}
+-
+ void raise_softirq(unsigned int nr)
+ {
+ 	unsigned long flags;
+@@ -424,12 +861,6 @@ void raise_softirq(unsigned int nr)
+ 	local_irq_restore(flags);
+ }
+ 
+-void __raise_softirq_irqoff(unsigned int nr)
+-{
+-	trace_softirq_raise(nr);
+-	or_softirq_pending(1UL << nr);
+-}
+-
+ void open_softirq(int nr, void (*action)(struct softirq_action *))
+ {
+ 	softirq_vec[nr].action = action;
+@@ -446,15 +877,45 @@ struct tasklet_head {
+ static DEFINE_PER_CPU(struct tasklet_head, tasklet_vec);
+ static DEFINE_PER_CPU(struct tasklet_head, tasklet_hi_vec);
+ 
++static void inline
++__tasklet_common_schedule(struct tasklet_struct *t, struct tasklet_head *head, unsigned int nr)
++{
++	if (tasklet_trylock(t)) {
++again:
++		/* We may have been preempted before tasklet_trylock
++		 * and __tasklet_action may have already run.
++		 * So double check the sched bit while the takslet
++		 * is locked before adding it to the list.
++		 */
++		if (test_bit(TASKLET_STATE_SCHED, &t->state)) {
++			t->next = NULL;
++			*head->tail = t;
++			head->tail = &(t->next);
++			raise_softirq_irqoff(nr);
++			tasklet_unlock(t);
++		} else {
++			/* This is subtle. If we hit the corner case above
++			 * It is possible that we get preempted right here,
++			 * and another task has successfully called
++			 * tasklet_schedule(), then this function, and
++			 * failed on the trylock. Thus we must be sure
++			 * before releasing the tasklet lock, that the
++			 * SCHED_BIT is clear. Otherwise the tasklet
++			 * may get its SCHED_BIT set, but not added to the
++			 * list
++			 */
++			if (!tasklet_tryunlock(t))
++				goto again;
++		}
++	}
++}
++
+ void __tasklet_schedule(struct tasklet_struct *t)
+ {
+ 	unsigned long flags;
+ 
+ 	local_irq_save(flags);
+-	t->next = NULL;
+-	*__this_cpu_read(tasklet_vec.tail) = t;
+-	__this_cpu_write(tasklet_vec.tail, &(t->next));
+-	raise_softirq_irqoff(TASKLET_SOFTIRQ);
++	__tasklet_common_schedule(t, this_cpu_ptr(&tasklet_vec), TASKLET_SOFTIRQ);
+ 	local_irq_restore(flags);
+ }
+ EXPORT_SYMBOL(__tasklet_schedule);
+@@ -464,10 +925,7 @@ void __tasklet_hi_schedule(struct tasklet_struct *t)
+ 	unsigned long flags;
+ 
+ 	local_irq_save(flags);
+-	t->next = NULL;
+-	*__this_cpu_read(tasklet_hi_vec.tail) = t;
+-	__this_cpu_write(tasklet_hi_vec.tail,  &(t->next));
+-	raise_softirq_irqoff(HI_SOFTIRQ);
++	__tasklet_common_schedule(t, this_cpu_ptr(&tasklet_hi_vec), HI_SOFTIRQ);
+ 	local_irq_restore(flags);
+ }
+ EXPORT_SYMBOL(__tasklet_hi_schedule);
+@@ -476,82 +934,122 @@ void __tasklet_hi_schedule_first(struct tasklet_struct *t)
+ {
+ 	BUG_ON(!irqs_disabled());
+ 
+-	t->next = __this_cpu_read(tasklet_hi_vec.head);
+-	__this_cpu_write(tasklet_hi_vec.head, t);
+-	__raise_softirq_irqoff(HI_SOFTIRQ);
++	__tasklet_hi_schedule(t);
+ }
+ EXPORT_SYMBOL(__tasklet_hi_schedule_first);
+ 
+-static void tasklet_action(struct softirq_action *a)
++void  tasklet_enable(struct tasklet_struct *t)
+ {
+-	struct tasklet_struct *list;
++	if (!atomic_dec_and_test(&t->count))
++		return;
++	if (test_and_clear_bit(TASKLET_STATE_PENDING, &t->state))
++		tasklet_schedule(t);
++}
++EXPORT_SYMBOL(tasklet_enable);
+ 
+-	local_irq_disable();
+-	list = __this_cpu_read(tasklet_vec.head);
+-	__this_cpu_write(tasklet_vec.head, NULL);
+-	__this_cpu_write(tasklet_vec.tail, this_cpu_ptr(&tasklet_vec.head));
+-	local_irq_enable();
++static void __tasklet_action(struct softirq_action *a,
++			     struct tasklet_struct *list)
++{
++	int loops = 1000000;
+ 
+ 	while (list) {
+ 		struct tasklet_struct *t = list;
+ 
+ 		list = list->next;
+ 
+-		if (tasklet_trylock(t)) {
+-			if (!atomic_read(&t->count)) {
+-				if (!test_and_clear_bit(TASKLET_STATE_SCHED,
+-							&t->state))
+-					BUG();
+-				t->func(t->data);
+-				tasklet_unlock(t);
+-				continue;
+-			}
+-			tasklet_unlock(t);
++		/*
++		 * Should always succeed - after a tasklist got on the
++		 * list (after getting the SCHED bit set from 0 to 1),
++		 * nothing but the tasklet softirq it got queued to can
++		 * lock it:
++		 */
++		if (!tasklet_trylock(t)) {
++			WARN_ON(1);
++			continue;
+ 		}
+ 
+-		local_irq_disable();
+ 		t->next = NULL;
+-		*__this_cpu_read(tasklet_vec.tail) = t;
+-		__this_cpu_write(tasklet_vec.tail, &(t->next));
+-		__raise_softirq_irqoff(TASKLET_SOFTIRQ);
+-		local_irq_enable();
++
++		/*
++		 * If we cannot handle the tasklet because it's disabled,
++		 * mark it as pending. tasklet_enable() will later
++		 * re-schedule the tasklet.
++		 */
++		if (unlikely(atomic_read(&t->count))) {
++out_disabled:
++			/* implicit unlock: */
++			wmb();
++			t->state = TASKLET_STATEF_PENDING;
++			continue;
++		}
++
++		/*
++		 * After this point on the tasklet might be rescheduled
++		 * on another CPU, but it can only be added to another
++		 * CPU's tasklet list if we unlock the tasklet (which we
++		 * dont do yet).
++		 */
++		if (!test_and_clear_bit(TASKLET_STATE_SCHED, &t->state))
++			WARN_ON(1);
++
++again:
++		t->func(t->data);
++
++		/*
++		 * Try to unlock the tasklet. We must use cmpxchg, because
++		 * another CPU might have scheduled or disabled the tasklet.
++		 * We only allow the STATE_RUN -> 0 transition here.
++		 */
++		while (!tasklet_tryunlock(t)) {
++			/*
++			 * If it got disabled meanwhile, bail out:
++			 */
++			if (atomic_read(&t->count))
++				goto out_disabled;
++			/*
++			 * If it got scheduled meanwhile, re-execute
++			 * the tasklet function:
++			 */
++			if (test_and_clear_bit(TASKLET_STATE_SCHED, &t->state))
++				goto again;
++			if (!--loops) {
++				printk("hm, tasklet state: %08lx\n", t->state);
++				WARN_ON(1);
++				tasklet_unlock(t);
++				break;
++			}
++		}
+ 	}
+ }
+ 
++static void tasklet_action(struct softirq_action *a)
++{
++	struct tasklet_struct *list;
++
++	local_irq_disable();
++
++	list = __this_cpu_read(tasklet_vec.head);
++	__this_cpu_write(tasklet_vec.head, NULL);
++	__this_cpu_write(tasklet_vec.tail, this_cpu_ptr(&tasklet_vec.head));
++
++	local_irq_enable();
++
++	__tasklet_action(a, list);
++}
++
+ static void tasklet_hi_action(struct softirq_action *a)
+ {
+ 	struct tasklet_struct *list;
+ 
+ 	local_irq_disable();
++
+ 	list = __this_cpu_read(tasklet_hi_vec.head);
+ 	__this_cpu_write(tasklet_hi_vec.head, NULL);
+ 	__this_cpu_write(tasklet_hi_vec.tail, this_cpu_ptr(&tasklet_hi_vec.head));
++
+ 	local_irq_enable();
+ 
+-	while (list) {
+-		struct tasklet_struct *t = list;
+-
+-		list = list->next;
+-
+-		if (tasklet_trylock(t)) {
+-			if (!atomic_read(&t->count)) {
+-				if (!test_and_clear_bit(TASKLET_STATE_SCHED,
+-							&t->state))
+-					BUG();
+-				t->func(t->data);
+-				tasklet_unlock(t);
+-				continue;
+-			}
+-			tasklet_unlock(t);
+-		}
+-
+-		local_irq_disable();
+-		t->next = NULL;
+-		*__this_cpu_read(tasklet_hi_vec.tail) = t;
+-		__this_cpu_write(tasklet_hi_vec.tail, &(t->next));
+-		__raise_softirq_irqoff(HI_SOFTIRQ);
+-		local_irq_enable();
+-	}
++	__tasklet_action(a, list);
+ }
+ 
+ void tasklet_init(struct tasklet_struct *t,
+@@ -572,7 +1070,7 @@ void tasklet_kill(struct tasklet_struct *t)
+ 
+ 	while (test_and_set_bit(TASKLET_STATE_SCHED, &t->state)) {
+ 		do {
+-			yield();
++			msleep(1);
+ 		} while (test_bit(TASKLET_STATE_SCHED, &t->state));
+ 	}
+ 	tasklet_unlock_wait(t);
+@@ -646,25 +1144,26 @@ void __init softirq_init(void)
+ 	open_softirq(HI_SOFTIRQ, tasklet_hi_action);
+ }
+ 
++#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT_FULL)
++void tasklet_unlock_wait(struct tasklet_struct *t)
++{
++	while (test_bit(TASKLET_STATE_RUN, &(t)->state)) {
++		/*
++		 * Hack for now to avoid this busy-loop:
++		 */
++#ifdef CONFIG_PREEMPT_RT_FULL
++		msleep(1);
++#else
++		barrier();
++#endif
++	}
++}
++EXPORT_SYMBOL(tasklet_unlock_wait);
++#endif
++
+ static int ksoftirqd_should_run(unsigned int cpu)
+ {
+-	return local_softirq_pending();
+-}
+-
+-static void run_ksoftirqd(unsigned int cpu)
+-{
+-	local_irq_disable();
+-	if (local_softirq_pending()) {
+-		/*
+-		 * We can safely run softirq on inline stack, as we are not deep
+-		 * in the task stack here.
+-		 */
+-		__do_softirq();
+-		local_irq_enable();
+-		cond_resched_rcu_qs();
+-		return;
+-	}
+-	local_irq_enable();
++	return ksoftirqd_softirq_pending();
+ }
+ 
+ #ifdef CONFIG_HOTPLUG_CPU
+@@ -746,16 +1245,31 @@ static struct notifier_block cpu_nfb = {
+ 
+ static struct smp_hotplug_thread softirq_threads = {
+ 	.store			= &ksoftirqd,
++	.setup			= ksoftirqd_set_sched_params,
+ 	.thread_should_run	= ksoftirqd_should_run,
+ 	.thread_fn		= run_ksoftirqd,
+ 	.thread_comm		= "ksoftirqd/%u",
+ };
+ 
++#ifdef CONFIG_PREEMPT_RT_FULL
++static struct smp_hotplug_thread softirq_timer_threads = {
++	.store			= &ktimer_softirqd,
++	.setup			= ktimer_softirqd_set_sched_params,
++	.cleanup		= ktimer_softirqd_clr_sched_params,
++	.thread_should_run	= ktimer_softirqd_should_run,
++	.thread_fn		= run_ksoftirqd,
++	.thread_comm		= "ktimersoftd/%u",
++};
++#endif
++
+ static __init int spawn_ksoftirqd(void)
+ {
+ 	register_cpu_notifier(&cpu_nfb);
+ 
+ 	BUG_ON(smpboot_register_percpu_thread(&softirq_threads));
++#ifdef CONFIG_PREEMPT_RT_FULL
++	BUG_ON(smpboot_register_percpu_thread(&softirq_timer_threads));
++#endif
+ 
+ 	return 0;
+ }
+diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c
+index a467e6c28a3b..d01a5118d58a 100644
+--- a/kernel/stop_machine.c
++++ b/kernel/stop_machine.c
+@@ -36,7 +36,7 @@ struct cpu_stop_done {
+ struct cpu_stopper {
+ 	struct task_struct	*thread;
+ 
+-	spinlock_t		lock;
++	raw_spinlock_t		lock;
+ 	bool			enabled;	/* is this stopper enabled? */
+ 	struct list_head	works;		/* list of pending works */
+ 
+@@ -82,14 +82,14 @@ static bool cpu_stop_queue_work(unsigned int cpu, struct cpu_stop_work *work)
+ 	unsigned long flags;
+ 	bool enabled;
+ 
+-	spin_lock_irqsave(&stopper->lock, flags);
++	raw_spin_lock_irqsave(&stopper->lock, flags);
+ 	enabled = stopper->enabled;
+ 	if (enabled)
+ 		__cpu_stop_queue_work(stopper, work);
+ 	else if (work->done)
+ 		cpu_stop_signal_done(work->done);
+-	spin_unlock_irqrestore(&stopper->lock, flags);
+ 
++	raw_spin_unlock_irqrestore(&stopper->lock, flags);
+ 	return enabled;
+ }
+ 
+@@ -224,8 +224,8 @@ static int cpu_stop_queue_two_works(int cpu1, struct cpu_stop_work *work1,
+ 	int err;
+ 
+ 	lg_double_lock(&stop_cpus_lock, cpu1, cpu2);
+-	spin_lock_irq(&stopper1->lock);
+-	spin_lock_nested(&stopper2->lock, SINGLE_DEPTH_NESTING);
++	raw_spin_lock_irq(&stopper1->lock);
++	raw_spin_lock_nested(&stopper2->lock, SINGLE_DEPTH_NESTING);
+ 
+ 	err = -ENOENT;
+ 	if (!stopper1->enabled || !stopper2->enabled)
+@@ -235,8 +235,8 @@ static int cpu_stop_queue_two_works(int cpu1, struct cpu_stop_work *work1,
+ 	__cpu_stop_queue_work(stopper1, work1);
+ 	__cpu_stop_queue_work(stopper2, work2);
+ unlock:
+-	spin_unlock(&stopper2->lock);
+-	spin_unlock_irq(&stopper1->lock);
++	raw_spin_unlock(&stopper2->lock);
++	raw_spin_unlock_irq(&stopper1->lock);
+ 	lg_double_unlock(&stop_cpus_lock, cpu1, cpu2);
+ 
+ 	return err;
+@@ -313,18 +313,21 @@ static DEFINE_MUTEX(stop_cpus_mutex);
+ 
+ static bool queue_stop_cpus_work(const struct cpumask *cpumask,
+ 				 cpu_stop_fn_t fn, void *arg,
+-				 struct cpu_stop_done *done)
++				 struct cpu_stop_done *done, bool inactive)
+ {
+ 	struct cpu_stop_work *work;
+ 	unsigned int cpu;
+ 	bool queued = false;
+ 
+ 	/*
+-	 * Disable preemption while queueing to avoid getting
+-	 * preempted by a stopper which might wait for other stoppers
+-	 * to enter @fn which can lead to deadlock.
++	 * Make sure that all work is queued on all cpus before
++	 * any of the cpus can execute it.
+ 	 */
+-	lg_global_lock(&stop_cpus_lock);
++	if (!inactive)
++		lg_global_lock(&stop_cpus_lock);
++	else
++		lg_global_trylock_relax(&stop_cpus_lock);
++
+ 	for_each_cpu(cpu, cpumask) {
+ 		work = &per_cpu(cpu_stopper.stop_work, cpu);
+ 		work->fn = fn;
+@@ -344,7 +347,7 @@ static int __stop_cpus(const struct cpumask *cpumask,
+ 	struct cpu_stop_done done;
+ 
+ 	cpu_stop_init_done(&done, cpumask_weight(cpumask));
+-	if (!queue_stop_cpus_work(cpumask, fn, arg, &done))
++	if (!queue_stop_cpus_work(cpumask, fn, arg, &done, false))
+ 		return -ENOENT;
+ 	wait_for_completion(&done.completion);
+ 	return done.ret;
+@@ -425,9 +428,9 @@ static int cpu_stop_should_run(unsigned int cpu)
+ 	unsigned long flags;
+ 	int run;
+ 
+-	spin_lock_irqsave(&stopper->lock, flags);
++	raw_spin_lock_irqsave(&stopper->lock, flags);
+ 	run = !list_empty(&stopper->works);
+-	spin_unlock_irqrestore(&stopper->lock, flags);
++	raw_spin_unlock_irqrestore(&stopper->lock, flags);
+ 	return run;
+ }
+ 
+@@ -438,13 +441,13 @@ static void cpu_stopper_thread(unsigned int cpu)
+ 
+ repeat:
+ 	work = NULL;
+-	spin_lock_irq(&stopper->lock);
++	raw_spin_lock_irq(&stopper->lock);
+ 	if (!list_empty(&stopper->works)) {
+ 		work = list_first_entry(&stopper->works,
+ 					struct cpu_stop_work, list);
+ 		list_del_init(&work->list);
+ 	}
+-	spin_unlock_irq(&stopper->lock);
++	raw_spin_unlock_irq(&stopper->lock);
+ 
+ 	if (work) {
+ 		cpu_stop_fn_t fn = work->fn;
+@@ -452,6 +455,16 @@ static void cpu_stopper_thread(unsigned int cpu)
+ 		struct cpu_stop_done *done = work->done;
+ 		int ret;
+ 
++		/*
++		 * Wait until the stopper finished scheduling on all
++		 * cpus
++		 */
++		lg_global_lock(&stop_cpus_lock);
++		/*
++		 * Let other cpu threads continue as well
++		 */
++		lg_global_unlock(&stop_cpus_lock);
++
+ 		/* cpu stop callbacks must not sleep, make in_atomic() == T */
+ 		preempt_count_inc();
+ 		ret = fn(arg);
+@@ -518,10 +531,12 @@ static int __init cpu_stop_init(void)
+ 	for_each_possible_cpu(cpu) {
+ 		struct cpu_stopper *stopper = &per_cpu(cpu_stopper, cpu);
+ 
+-		spin_lock_init(&stopper->lock);
++		raw_spin_lock_init(&stopper->lock);
+ 		INIT_LIST_HEAD(&stopper->works);
+ 	}
+ 
++	lg_lock_init(&stop_cpus_lock, "stop_cpus_lock");
++
+ 	BUG_ON(smpboot_register_percpu_thread(&cpu_stop_threads));
+ 	stop_machine_unpark(raw_smp_processor_id());
+ 	stop_machine_initialized = true;
+@@ -616,7 +631,7 @@ int stop_machine_from_inactive_cpu(cpu_stop_fn_t fn, void *data,
+ 	set_state(&msdata, MULTI_STOP_PREPARE);
+ 	cpu_stop_init_done(&done, num_active_cpus());
+ 	queue_stop_cpus_work(cpu_active_mask, multi_cpu_stop, &msdata,
+-			     &done);
++			     &done, true);
+ 	ret = multi_cpu_stop(&msdata);
+ 
+ 	/* Busy wait for completion. */
+diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
+index fa0b983290cf..ab846abc8b7b 100644
+--- a/kernel/time/hrtimer.c
++++ b/kernel/time/hrtimer.c
+@@ -48,11 +48,13 @@
+ #include <linux/sched/rt.h>
+ #include <linux/sched/deadline.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>
+ 
+ #include "tick-internal.h"
+ 
+@@ -706,6 +708,44 @@ static void clock_was_set_work(struct work_struct *work)
+ 
+ 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.
+@@ -714,6 +754,7 @@ void clock_was_set_delayed(void)
+ {
+ 	schedule_work(&hrtimer_work);
+ }
++#endif
+ 
+ #else
+ 
+@@ -723,11 +764,8 @@ static inline int hrtimer_is_hres_enabled(void) { return 0; }
+ static inline void hrtimer_switch_to_hres(void) { }
+ static inline void
+ hrtimer_force_reprogram(struct hrtimer_cpu_base *base, int skip_equal) { }
+-static inline int hrtimer_reprogram(struct hrtimer *timer,
+-				    struct hrtimer_clock_base *base)
+-{
+-	return 0;
+-}
++static inline void hrtimer_reprogram(struct hrtimer *timer,
++				     struct hrtimer_clock_base *base) { }
+ static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base) { }
+ static inline void retrigger_next_event(void *arg) { }
+ 
+@@ -859,6 +897,32 @@ u64 hrtimer_forward(struct hrtimer *timer, ktime_t now, ktime_t interval)
+ }
+ 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,
++				!(hrtimer_callback_running(timer)));
++}
++
++#else
++# define wake_up_timer_waiters(b)	do { } while (0)
++#endif
++
+ /*
+  * enqueue_hrtimer - internal function to (re)start a timer
+  *
+@@ -900,6 +964,11 @@ static void __remove_hrtimer(struct hrtimer *timer,
+ 	if (!(state & HRTIMER_STATE_ENQUEUED))
+ 		return;
+ 
++	if (unlikely(!list_empty(&timer->cb_entry))) {
++		list_del_init(&timer->cb_entry);
++		return;
++	}
++
+ 	if (!timerqueue_del(&base->active, &timer->node))
+ 		cpu_base->active_bases &= ~(1 << base->index);
+ 
+@@ -995,7 +1064,16 @@ void hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,
+ 	new_base = switch_hrtimer_base(timer, base, mode & HRTIMER_MODE_PINNED);
+ 
+ 	timer_stats_hrtimer_set_start_info(timer);
++#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
+ 	leftmost = enqueue_hrtimer(timer, new_base);
+ 	if (!leftmost)
+ 		goto unlock;
+@@ -1067,7 +1145,7 @@ int hrtimer_cancel(struct hrtimer *timer)
+ 
+ 		if (ret >= 0)
+ 			return ret;
+-		cpu_relax();
++		hrtimer_wait_for_timer(timer);
+ 	}
+ }
+ EXPORT_SYMBOL_GPL(hrtimer_cancel);
+@@ -1131,6 +1209,7 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
+ 
+ 	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
+@@ -1171,6 +1250,7 @@ bool hrtimer_active(const struct hrtimer *timer)
+ 		seq = raw_read_seqcount_begin(&cpu_base->seq);
+ 
+ 		if (timer->state != HRTIMER_STATE_INACTIVE ||
++		    cpu_base->running_soft == timer ||
+ 		    cpu_base->running == timer)
+ 			return true;
+ 
+@@ -1269,10 +1349,112 @@ static void __run_hrtimer(struct hrtimer_cpu_base *cpu_base,
+ 	cpu_base->running = NULL;
+ }
+ 
++#ifdef CONFIG_PREEMPT_RT_BASE
++static void hrtimer_rt_reprogram(int restart, struct hrtimer *timer,
++				 struct hrtimer_clock_base *base)
++{
++	int leftmost;
++
++	if (restart != HRTIMER_NORESTART &&
++	    !(timer->state & HRTIMER_STATE_ENQUEUED)) {
++
++		leftmost = enqueue_hrtimer(timer, base);
++		if (!leftmost)
++			return;
++#ifdef CONFIG_HIGH_RES_TIMERS
++		if (!hrtimer_is_hres_active(timer)) {
++			/*
++			 * Kick to reschedule the next tick to handle the new timer
++			 * on dynticks target.
++			 */
++			if (base->cpu_base->nohz_active)
++				wake_up_nohz_cpu(base->cpu_base->cpu);
++		} else {
++
++			hrtimer_reprogram(timer, base);
++		}
++#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_deactivate(timer);
++			cpu_base->running_soft = timer;
++			raw_write_seqcount_barrier(&cpu_base->seq);
++
++			__remove_hrtimer(timer, base, HRTIMER_STATE_INACTIVE, 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_write_seqcount_barrier(&cpu_base->seq);
++
++			WARN_ON_ONCE(cpu_base->running_soft != timer);
++			cpu_base->running_soft = NULL;
++		}
++	}
++
++	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 int hrtimer_rt_defer(struct hrtimer *timer) { return 0; }
++
++#endif
++
++static enum hrtimer_restart hrtimer_wakeup(struct hrtimer *timer);
++
+ static void __hrtimer_run_queues(struct hrtimer_cpu_base *cpu_base, ktime_t now)
+ {
+ 	struct hrtimer_clock_base *base = cpu_base->clock_base;
+ 	unsigned int active = cpu_base->active_bases;
++	int raise = 0;
+ 
+ 	for (; active; base++, active >>= 1) {
+ 		struct timerqueue_node *node;
+@@ -1288,6 +1470,15 @@ static void __hrtimer_run_queues(struct hrtimer_cpu_base *cpu_base, ktime_t now)
+ 
+ 			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
+@@ -1303,9 +1494,14 @@ static void __hrtimer_run_queues(struct hrtimer_cpu_base *cpu_base, ktime_t now)
+ 			if (basenow.tv64 < hrtimer_get_softexpires_tv64(timer))
+ 				break;
+ 
+-			__run_hrtimer(cpu_base, base, timer, &basenow);
++			if (!hrtimer_rt_defer(timer))
++				__run_hrtimer(cpu_base, base, timer, &basenow);
++			else
++				raise = 1;
+ 		}
+ 	}
++	if (raise)
++		raise_softirq_irqoff(HRTIMER_SOFTIRQ);
+ }
+ 
+ #ifdef CONFIG_HIGH_RES_TIMERS
+@@ -1468,16 +1664,18 @@ static enum hrtimer_restart hrtimer_wakeup(struct hrtimer *timer)
+ 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 (likely(t->task))
+@@ -1519,7 +1717,8 @@ long __sched hrtimer_nanosleep_restart(struct restart_block *restart)
+ 				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;
+@@ -1536,8 +1735,10 @@ long __sched hrtimer_nanosleep_restart(struct restart_block *restart)
+ 	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;
+@@ -1550,7 +1751,7 @@ long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
+ 
+ 	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: */
+@@ -1577,6 +1778,12 @@ long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
+ 	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)
+ {
+@@ -1591,6 +1798,26 @@ SYSCALL_DEFINE2(nanosleep, struct timespec __user *, rqtp,
+ 	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:
+  */
+@@ -1602,10 +1829,14 @@ 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);
+ 	}
+ 
+ 	cpu_base->cpu = cpu;
+ 	hrtimer_init_hres(cpu_base);
++#ifdef CONFIG_PREEMPT_RT_BASE
++	init_waitqueue_head(&cpu_base->wait);
++#endif
+ }
+ 
+ #ifdef CONFIG_HOTPLUG_CPU
+@@ -1703,11 +1934,21 @@ static struct notifier_block hrtimers_nb = {
+ 	.notifier_call = hrtimer_cpu_notify,
+ };
+ 
++#ifdef CONFIG_PREEMPT_RT_BASE
++static void run_hrtimer_softirq(struct softirq_action *h)
++{
++	hrtimer_rt_run_pending();
++}
++#endif
++
+ 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_PREEMPT_RT_BASE
++	open_softirq(HRTIMER_SOFTIRQ, run_hrtimer_softirq);
++#endif
+ }
+ 
+ /**
+diff --git a/kernel/time/itimer.c b/kernel/time/itimer.c
+index 1d5c7204ddc9..184de6751180 100644
+--- a/kernel/time/itimer.c
++++ b/kernel/time/itimer.c
+@@ -213,6 +213,7 @@ int do_setitimer(int which, struct itimerval *value, struct itimerval *ovalue)
+ 		/* 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);
+diff --git a/kernel/time/jiffies.c b/kernel/time/jiffies.c
+index 555e21f7b966..a5d6435fabbb 100644
+--- a/kernel/time/jiffies.c
++++ b/kernel/time/jiffies.c
+@@ -74,7 +74,8 @@ static struct clocksource clocksource_jiffies = {
+ 	.max_cycles	= 10,
+ };
+ 
+-__cacheline_aligned_in_smp DEFINE_SEQLOCK(jiffies_lock);
++__cacheline_aligned_in_smp DEFINE_RAW_SPINLOCK(jiffies_lock);
++__cacheline_aligned_in_smp seqcount_t jiffies_seq;
+ 
+ #if (BITS_PER_LONG < 64)
+ u64 get_jiffies_64(void)
+@@ -83,9 +84,9 @@ u64 get_jiffies_64(void)
+ 	u64 ret;
+ 
+ 	do {
+-		seq = read_seqbegin(&jiffies_lock);
++		seq = read_seqcount_begin(&jiffies_seq);
+ 		ret = jiffies_64;
+-	} while (read_seqretry(&jiffies_lock, seq));
++	} while (read_seqcount_retry(&jiffies_seq, seq));
+ 	return ret;
+ }
+ EXPORT_SYMBOL(get_jiffies_64);
+diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
+index 6df8927c58a5..6b4c19fa233f 100644
+--- a/kernel/time/ntp.c
++++ b/kernel/time/ntp.c
+@@ -10,6 +10,7 @@
+ #include <linux/workqueue.h>
+ #include <linux/hrtimer.h>
+ #include <linux/jiffies.h>
++#include <linux/kthread.h>
+ #include <linux/math64.h>
+ #include <linux/timex.h>
+ #include <linux/time.h>
+@@ -568,10 +569,52 @@ static void sync_cmos_clock(struct work_struct *work)
+ 			   &sync_cmos_work, timespec64_to_jiffies(&next));
+ }
+ 
++#ifdef CONFIG_PREEMPT_RT_FULL
++/*
++ * RT can not call schedule_delayed_work from real interrupt context.
++ * Need to make a thread to do the real work.
++ */
++static struct task_struct *cmos_delay_thread;
++static bool do_cmos_delay;
++
++static int run_cmos_delay(void *ignore)
++{
++	while (!kthread_should_stop()) {
++		set_current_state(TASK_INTERRUPTIBLE);
++		if (do_cmos_delay) {
++			do_cmos_delay = false;
++			queue_delayed_work(system_power_efficient_wq,
++					   &sync_cmos_work, 0);
++		}
++		schedule();
++	}
++	__set_current_state(TASK_RUNNING);
++	return 0;
++}
++
++void ntp_notify_cmos_timer(void)
++{
++	do_cmos_delay = true;
++	/* Make visible before waking up process */
++	smp_wmb();
++	wake_up_process(cmos_delay_thread);
++}
++
++static __init int create_cmos_delay_thread(void)
++{
++	cmos_delay_thread = kthread_run(run_cmos_delay, NULL, "kcmosdelayd");
++	BUG_ON(!cmos_delay_thread);
++	return 0;
++}
++early_initcall(create_cmos_delay_thread);
++
++#else
++
+ void ntp_notify_cmos_timer(void)
+ {
+ 	queue_delayed_work(system_power_efficient_wq, &sync_cmos_work, 0);
+ }
++#endif /* CONFIG_PREEMPT_RT_FULL */
+ 
+ #else
+ void ntp_notify_cmos_timer(void) { }
+diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
+index 1cafba860b08..5f16807aa3ff 100644
+--- a/kernel/time/posix-cpu-timers.c
++++ b/kernel/time/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>
+@@ -620,7 +621,7 @@ static int posix_cpu_timer_set(struct k_itimer *timer, int timer_flags,
+ 	/*
+ 	 * Disarm any old timer after extracting its expiry time.
+ 	 */
+-	WARN_ON_ONCE(!irqs_disabled());
++	WARN_ON_ONCE_NONRT(!irqs_disabled());
+ 
+ 	ret = 0;
+ 	old_incr = timer->it.cpu.incr;
+@@ -1063,7 +1064,7 @@ void posix_cpu_timer_schedule(struct k_itimer *timer)
+ 	/*
+ 	 * Now re-arm for the new expiry time.
+ 	 */
+-	WARN_ON_ONCE(!irqs_disabled());
++	WARN_ON_ONCE_NONRT(!irqs_disabled());
+ 	arm_timer(timer);
+ 	unlock_task_sighand(p, &flags);
+ 
+@@ -1152,13 +1153,13 @@ static inline int fastpath_timer_check(struct task_struct *tsk)
+  * 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;
+ 
+-	WARN_ON_ONCE(!irqs_disabled());
++	WARN_ON_ONCE_NONRT(!irqs_disabled());
+ 
+ 	/*
+ 	 * The fast path checks that there are no expired thread or thread
+@@ -1212,6 +1213,190 @@ void run_posix_cpu_timers(struct task_struct *tsk)
+ 	}
+ }
+ 
++#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.
+diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
+index f2826c35e918..464a98155a0e 100644
+--- a/kernel/time/posix-timers.c
++++ b/kernel/time/posix-timers.c
+@@ -506,6 +506,7 @@ static enum hrtimer_restart posix_timer_fn(struct hrtimer *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)) ||
+@@ -514,7 +515,8 @@ static struct pid *good_sigevent(sigevent_t * event)
+ 		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);
+@@ -826,6 +828,20 @@ SYSCALL_DEFINE1(timer_getoverrun, timer_t, timer_id)
+ 	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
+@@ -903,6 +919,7 @@ SYSCALL_DEFINE4(timer_settime, timer_t, timer_id, int, flags,
+ 	if (!timr)
+ 		return -EINVAL;
+ 
++	rcu_read_lock();
+ 	kc = clockid_to_kclock(timr->it_clock);
+ 	if (WARN_ON_ONCE(!kc || !kc->timer_set))
+ 		error = -EINVAL;
+@@ -911,9 +928,12 @@ SYSCALL_DEFINE4(timer_settime, timer_t, timer_id, int, flags,
+ 
+ 	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)))
+@@ -951,10 +971,15 @@ SYSCALL_DEFINE1(timer_delete, timer_t, timer_id)
+ 	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);
+@@ -980,8 +1005,18 @@ static void itimer_delete(struct k_itimer *timer)
+ retry_delete:
+ 	spin_lock_irqsave(&timer->it_lock, flags);
+ 
+-	if (timer_delete_hook(timer) == TIMER_RETRY) {
++	/* 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);
+diff --git a/kernel/time/tick-broadcast-hrtimer.c b/kernel/time/tick-broadcast-hrtimer.c
+index 53d7184da0be..1b4ac3361c3f 100644
+--- a/kernel/time/tick-broadcast-hrtimer.c
++++ b/kernel/time/tick-broadcast-hrtimer.c
+@@ -106,5 +106,6 @@ void tick_setup_hrtimer_broadcast(void)
+ {
+ 	hrtimer_init(&bctimer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
+ 	bctimer.function = bc_handler;
++	bctimer.irqsafe = true;
+ 	clockevents_register_device(&ce_broadcast_hrtimer);
+ }
+diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c
+index 4fcd99e12aa0..5a47f2e98faf 100644
+--- a/kernel/time/tick-common.c
++++ b/kernel/time/tick-common.c
+@@ -79,13 +79,15 @@ int tick_is_oneshot_available(void)
+ static void tick_periodic(int cpu)
+ {
+ 	if (tick_do_timer_cpu == cpu) {
+-		write_seqlock(&jiffies_lock);
++		raw_spin_lock(&jiffies_lock);
++		write_seqcount_begin(&jiffies_seq);
+ 
+ 		/* Keep track of the next tick event */
+ 		tick_next_period = ktime_add(tick_next_period, tick_period);
+ 
+ 		do_timer(1);
+-		write_sequnlock(&jiffies_lock);
++		write_seqcount_end(&jiffies_seq);
++		raw_spin_unlock(&jiffies_lock);
+ 		update_wall_time();
+ 	}
+ 
+@@ -157,9 +159,9 @@ void tick_setup_periodic(struct clock_event_device *dev, int broadcast)
+ 		ktime_t next;
+ 
+ 		do {
+-			seq = read_seqbegin(&jiffies_lock);
++			seq = read_seqcount_begin(&jiffies_seq);
+ 			next = tick_next_period;
+-		} while (read_seqretry(&jiffies_lock, seq));
++		} while (read_seqcount_retry(&jiffies_seq, seq));
+ 
+ 		clockevents_switch_state(dev, CLOCK_EVT_STATE_ONESHOT);
+ 
+diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h
+index 966a5a6fdd0a..f738251000fe 100644
+--- a/kernel/time/tick-internal.h
++++ b/kernel/time/tick-internal.h
+@@ -164,3 +164,4 @@ static inline void timers_update_migration(bool update_nohz) { }
+ DECLARE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases);
+ 
+ extern u64 get_next_timer_interrupt(unsigned long basej, u64 basem);
++void timer_clear_idle(void);
+diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
+index 58e3310c9b21..6fc9a5fdd5f4 100644
+--- a/kernel/time/tick-sched.c
++++ b/kernel/time/tick-sched.c
+@@ -62,7 +62,8 @@ static void tick_do_update_jiffies64(ktime_t now)
+ 		return;
+ 
+ 	/* Reevalute with jiffies_lock held */
+-	write_seqlock(&jiffies_lock);
++	raw_spin_lock(&jiffies_lock);
++	write_seqcount_begin(&jiffies_seq);
+ 
+ 	delta = ktime_sub(now, last_jiffies_update);
+ 	if (delta.tv64 >= tick_period.tv64) {
+@@ -85,10 +86,12 @@ static void tick_do_update_jiffies64(ktime_t now)
+ 		/* Keep the tick_next_period variable up to date */
+ 		tick_next_period = ktime_add(last_jiffies_update, tick_period);
+ 	} else {
+-		write_sequnlock(&jiffies_lock);
++		write_seqcount_end(&jiffies_seq);
++		raw_spin_unlock(&jiffies_lock);
+ 		return;
+ 	}
+-	write_sequnlock(&jiffies_lock);
++	write_seqcount_end(&jiffies_seq);
++	raw_spin_unlock(&jiffies_lock);
+ 	update_wall_time();
+ }
+ 
+@@ -99,12 +102,14 @@ static ktime_t tick_init_jiffy_update(void)
+ {
+ 	ktime_t period;
+ 
+-	write_seqlock(&jiffies_lock);
++	raw_spin_lock(&jiffies_lock);
++	write_seqcount_begin(&jiffies_seq);
+ 	/* Did we start the jiffies update yet ? */
+ 	if (last_jiffies_update.tv64 == 0)
+ 		last_jiffies_update = tick_next_period;
+ 	period = last_jiffies_update;
+-	write_sequnlock(&jiffies_lock);
++	write_seqcount_end(&jiffies_seq);
++	raw_spin_unlock(&jiffies_lock);
+ 	return period;
+ }
+ 
+@@ -212,6 +217,7 @@ static void nohz_full_kick_func(struct irq_work *work)
+ 
+ static DEFINE_PER_CPU(struct irq_work, nohz_full_kick_work) = {
+ 	.func = nohz_full_kick_func,
++	.flags = IRQ_WORK_HARD_IRQ,
+ };
+ 
+ /*
+@@ -670,10 +676,10 @@ static ktime_t tick_nohz_stop_sched_tick(struct tick_sched *ts,
+ 
+ 	/* Read jiffies and the time when jiffies were updated last */
+ 	do {
+-		seq = read_seqbegin(&jiffies_lock);
++		seq = read_seqcount_begin(&jiffies_seq);
+ 		basemono = last_jiffies_update.tv64;
+ 		basejiff = jiffies;
+-	} while (read_seqretry(&jiffies_lock, seq));
++	} while (read_seqcount_retry(&jiffies_seq, seq));
+ 	ts->last_jiffies = basejiff;
+ 
+ 	if (rcu_needs_cpu(basemono, &next_rcu) ||
+@@ -700,6 +706,12 @@ static ktime_t tick_nohz_stop_sched_tick(struct tick_sched *ts,
+ 	delta = next_tick - basemono;
+ 	if (delta <= (u64)TICK_NSEC) {
+ 		tick.tv64 = 0;
++
++		/*
++		 * Tell the timer code that the base is not idle, i.e. undo
++		 * the effect of get_next_timer_interrupt().
++		 */
++		timer_clear_idle();
+ 		/*
+ 		 * We've not stopped the tick yet, and there's a timer in the
+ 		 * next period, so no point in stopping it either, bail.
+@@ -808,6 +820,12 @@ static void tick_nohz_restart_sched_tick(struct tick_sched *ts, ktime_t now, int
+ 	tick_do_update_jiffies64(now);
+ 	update_cpu_load_nohz(active);
+ 
++	/*
++	 * Clear the timer idle flag, so we avoid IPIs on remote queueing and
++	 * the clock forward checks in the enqueue path.
++	 */
++	timer_clear_idle();
++
+ 	calc_load_exit_idle();
+ 	touch_softlockup_watchdog_sched();
+ 	/*
+@@ -861,14 +879,7 @@ static bool can_stop_idle_tick(int cpu, struct tick_sched *ts)
+ 		return false;
+ 
+ 	if (unlikely(local_softirq_pending() && cpu_online(cpu))) {
+-		static int ratelimit;
+-
+-		if (ratelimit < 10 &&
+-		    (local_softirq_pending() & SOFTIRQ_STOP_IDLE_MASK)) {
+-			pr_warn("NOHZ: local_softirq_pending %02x\n",
+-				(unsigned int) local_softirq_pending());
+-			ratelimit++;
+-		}
++		softirq_check_pending_idle();
+ 		return false;
+ 	}
+ 
+@@ -1091,35 +1102,6 @@ static void tick_nohz_switch_to_nohz(void)
+ 	tick_nohz_activate(ts, NOHZ_MODE_LOWRES);
+ }
+ 
+-/*
+- * When NOHZ is enabled and the tick is stopped, we need to kick the
+- * tick timer from irq_enter() so that the jiffies update is kept
+- * alive during long running softirqs. That's ugly as hell, but
+- * correctness is key even if we need to fix the offending softirq in
+- * the first place.
+- *
+- * Note, this is different to tick_nohz_restart. We just kick the
+- * timer and do not touch the other magic bits which need to be done
+- * when idle is left.
+- */
+-static void tick_nohz_kick_tick(struct tick_sched *ts, ktime_t now)
+-{
+-#if 0
+-	/* Switch back to 2.6.27 behaviour */
+-	ktime_t delta;
+-
+-	/*
+-	 * Do not touch the tick device, when the next expiry is either
+-	 * already reached or less/equal than the tick period.
+-	 */
+-	delta =	ktime_sub(hrtimer_get_expires(&ts->sched_timer), now);
+-	if (delta.tv64 <= tick_period.tv64)
+-		return;
+-
+-	tick_nohz_restart(ts, now);
+-#endif
+-}
+-
+ static inline void tick_nohz_irq_enter(void)
+ {
+ 	struct tick_sched *ts = this_cpu_ptr(&tick_cpu_sched);
+@@ -1130,10 +1112,8 @@ static inline void tick_nohz_irq_enter(void)
+ 	now = ktime_get();
+ 	if (ts->idle_active)
+ 		tick_nohz_stop_idle(ts, now);
+-	if (ts->tick_stopped) {
++	if (ts->tick_stopped)
+ 		tick_nohz_update_jiffies(now);
+-		tick_nohz_kick_tick(ts, now);
+-	}
+ }
+ 
+ #else
+@@ -1208,6 +1188,7 @@ void tick_setup_sched_timer(void)
+ 	 * Emulate tick processing via per-CPU hrtimers:
+ 	 */
+ 	hrtimer_init(&ts->sched_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
++	ts->sched_timer.irqsafe = 1;
+ 	ts->sched_timer.function = tick_sched_timer;
+ 
+ 	/* Get the next period (per cpu) */
+diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
+index 479d25cd3d4f..410c04b386e4 100644
+--- a/kernel/time/timekeeping.c
++++ b/kernel/time/timekeeping.c
+@@ -2319,8 +2319,10 @@ EXPORT_SYMBOL(hardpps);
+  */
+ void xtime_update(unsigned long ticks)
+ {
+-	write_seqlock(&jiffies_lock);
++	raw_spin_lock(&jiffies_lock);
++	write_seqcount_begin(&jiffies_seq);
+ 	do_timer(ticks);
+-	write_sequnlock(&jiffies_lock);
++	write_seqcount_end(&jiffies_seq);
++	raw_spin_unlock(&jiffies_lock);
+ 	update_wall_time();
+ }
+diff --git a/kernel/time/timekeeping.h b/kernel/time/timekeeping.h
+index 704f595ce83f..763a3e5121ff 100644
+--- a/kernel/time/timekeeping.h
++++ b/kernel/time/timekeeping.h
+@@ -19,7 +19,8 @@ extern void timekeeping_resume(void);
+ extern void do_timer(unsigned long ticks);
+ extern void update_wall_time(void);
+ 
+-extern seqlock_t jiffies_lock;
++extern raw_spinlock_t jiffies_lock;
++extern seqcount_t jiffies_seq;
+ 
+ #define CS_NAME_LEN	32
+ 
+diff --git a/kernel/time/timer.c b/kernel/time/timer.c
+index 73164c3aa56b..b1d2d4026cfe 100644
+--- a/kernel/time/timer.c
++++ b/kernel/time/timer.c
+@@ -59,43 +59,156 @@ __visible u64 jiffies_64 __cacheline_aligned_in_smp = INITIAL_JIFFIES;
+ EXPORT_SYMBOL(jiffies_64);
+ 
+ /*
+- * per-CPU timer vector definitions:
++ * The timer wheel has LVL_DEPTH array levels. Each level provides an array of
++ * LVL_SIZE buckets. Each level is driven by its own clock and therefor each
++ * level has a different granularity.
++ *
++ * The level granularity is:		LVL_CLK_DIV ^ lvl
++ * The level clock frequency is:	HZ / (LVL_CLK_DIV ^ level)
++ *
++ * The array level of a newly armed timer depends on the relative expiry
++ * time. The farther the expiry time is away the higher the array level and
++ * therefor the granularity becomes.
++ *
++ * Contrary to the original timer wheel implementation, which aims for 'exact'
++ * expiry of the timers, this implementation removes the need for recascading
++ * the timers into the lower array levels. The previous 'classic' timer wheel
++ * implementation of the kernel already violated the 'exact' expiry by adding
++ * slack to the expiry time to provide batched expiration. The granularity
++ * levels provide implicit batching.
++ *
++ * This is an optimization of the original timer wheel implementation for the
++ * majority of the timer wheel use cases: timeouts. The vast majority of
++ * timeout timers (networking, disk I/O ...) are canceled before expiry. If
++ * the timeout expires it indicates that normal operation is disturbed, so it
++ * does not matter much whether the timeout comes with a slight delay.
++ *
++ * The only exception to this are networking timers with a small expiry
++ * time. They rely on the granularity. Those fit into the first wheel level,
++ * which has HZ granularity.
++ *
++ * We don't have cascading anymore. timers with a expiry time above the
++ * capacity of the last wheel level are force expired at the maximum timeout
++ * value of the last wheel level. From data sampling we know that the maximum
++ * value observed is 5 days (network connection tracking), so this should not
++ * be an issue.
++ *
++ * The currently chosen array constants values are a good compromise between
++ * array size and granularity.
++ *
++ * This results in the following granularity and range levels:
++ *
++ * HZ 1000 steps
++ * Level Offset  Granularity            Range
++ *  0      0         1 ms                0 ms -         63 ms
++ *  1     64         8 ms               64 ms -        511 ms
++ *  2    128        64 ms              512 ms -       4095 ms (512ms - ~4s)
++ *  3    192       512 ms             4096 ms -      32767 ms (~4s - ~32s)
++ *  4    256      4096 ms (~4s)      32768 ms -     262143 ms (~32s - ~4m)
++ *  5    320     32768 ms (~32s)    262144 ms -    2097151 ms (~4m - ~34m)
++ *  6    384    262144 ms (~4m)    2097152 ms -   16777215 ms (~34m - ~4h)
++ *  7    448   2097152 ms (~34m)  16777216 ms -  134217727 ms (~4h - ~1d)
++ *  8    512  16777216 ms (~4h)  134217728 ms - 1073741822 ms (~1d - ~12d)
++ *
++ * HZ  300
++ * Level Offset  Granularity            Range
++ *  0	   0         3 ms                0 ms -        210 ms
++ *  1	  64        26 ms              213 ms -       1703 ms (213ms - ~1s)
++ *  2	 128       213 ms             1706 ms -      13650 ms (~1s - ~13s)
++ *  3	 192      1706 ms (~1s)      13653 ms -     109223 ms (~13s - ~1m)
++ *  4	 256     13653 ms (~13s)    109226 ms -     873810 ms (~1m - ~14m)
++ *  5	 320    109226 ms (~1m)     873813 ms -    6990503 ms (~14m - ~1h)
++ *  6	 384    873813 ms (~14m)   6990506 ms -   55924050 ms (~1h - ~15h)
++ *  7	 448   6990506 ms (~1h)   55924053 ms -  447392423 ms (~15h - ~5d)
++ *  8    512  55924053 ms (~15h) 447392426 ms - 3579139406 ms (~5d - ~41d)
++ *
++ * HZ  250
++ * Level Offset  Granularity            Range
++ *  0	   0         4 ms                0 ms -        255 ms
++ *  1	  64        32 ms              256 ms -       2047 ms (256ms - ~2s)
++ *  2	 128       256 ms             2048 ms -      16383 ms (~2s - ~16s)
++ *  3	 192      2048 ms (~2s)      16384 ms -     131071 ms (~16s - ~2m)
++ *  4	 256     16384 ms (~16s)    131072 ms -    1048575 ms (~2m - ~17m)
++ *  5	 320    131072 ms (~2m)    1048576 ms -    8388607 ms (~17m - ~2h)
++ *  6	 384   1048576 ms (~17m)   8388608 ms -   67108863 ms (~2h - ~18h)
++ *  7	 448   8388608 ms (~2h)   67108864 ms -  536870911 ms (~18h - ~6d)
++ *  8    512  67108864 ms (~18h) 536870912 ms - 4294967288 ms (~6d - ~49d)
++ *
++ * HZ  100
++ * Level Offset  Granularity            Range
++ *  0	   0         10 ms               0 ms -        630 ms
++ *  1	  64         80 ms             640 ms -       5110 ms (640ms - ~5s)
++ *  2	 128        640 ms            5120 ms -      40950 ms (~5s - ~40s)
++ *  3	 192       5120 ms (~5s)     40960 ms -     327670 ms (~40s - ~5m)
++ *  4	 256      40960 ms (~40s)   327680 ms -    2621430 ms (~5m - ~43m)
++ *  5	 320     327680 ms (~5m)   2621440 ms -   20971510 ms (~43m - ~5h)
++ *  6	 384    2621440 ms (~43m) 20971520 ms -  167772150 ms (~5h - ~1d)
++ *  7	 448   20971520 ms (~5h) 167772160 ms - 1342177270 ms (~1d - ~15d)
+  */
+-#define TVN_BITS (CONFIG_BASE_SMALL ? 4 : 6)
+-#define TVR_BITS (CONFIG_BASE_SMALL ? 6 : 8)
+-#define TVN_SIZE (1 << TVN_BITS)
+-#define TVR_SIZE (1 << TVR_BITS)
+-#define TVN_MASK (TVN_SIZE - 1)
+-#define TVR_MASK (TVR_SIZE - 1)
+-#define MAX_TVAL ((unsigned long)((1ULL << (TVR_BITS + 4*TVN_BITS)) - 1))
+ 
+-struct tvec {
+-	struct hlist_head vec[TVN_SIZE];
+-};
++/* Clock divisor for the next level */
++#define LVL_CLK_SHIFT	3
++#define LVL_CLK_DIV	(1UL << LVL_CLK_SHIFT)
++#define LVL_CLK_MASK	(LVL_CLK_DIV - 1)
++#define LVL_SHIFT(n)	((n) * LVL_CLK_SHIFT)
++#define LVL_GRAN(n)	(1UL << LVL_SHIFT(n))
+ 
+-struct tvec_root {
+-	struct hlist_head vec[TVR_SIZE];
+-};
++/*
++ * The time start value for each level to select the bucket at enqueue
++ * time.
++ */
++#define LVL_START(n)	((LVL_SIZE - 1) << (((n) - 1) * LVL_CLK_SHIFT))
+ 
+-struct tvec_base {
+-	spinlock_t lock;
+-	struct timer_list *running_timer;
+-	unsigned long timer_jiffies;
+-	unsigned long next_timer;
+-	unsigned long active_timers;
+-	unsigned long all_timers;
+-	int cpu;
+-	bool migration_enabled;
+-	bool nohz_active;
+-	struct tvec_root tv1;
+-	struct tvec tv2;
+-	struct tvec tv3;
+-	struct tvec tv4;
+-	struct tvec tv5;
++/* Size of each clock level */
++#define LVL_BITS	6
++#define LVL_SIZE	(1UL << LVL_BITS)
++#define LVL_MASK	(LVL_SIZE - 1)
++#define LVL_OFFS(n)	((n) * LVL_SIZE)
++
++/* Level depth */
++#if HZ > 100
++# define LVL_DEPTH	9
++# else
++# define LVL_DEPTH	8
++#endif
++
++/* The cutoff (max. capacity of the wheel) */
++#define WHEEL_TIMEOUT_CUTOFF	(LVL_START(LVL_DEPTH))
++#define WHEEL_TIMEOUT_MAX	(WHEEL_TIMEOUT_CUTOFF - LVL_GRAN(LVL_DEPTH - 1))
++
++/*
++ * The resulting wheel size. If NOHZ is configured we allocate two
++ * wheels so we have a separate storage for the deferrable timers.
++ */
++#define WHEEL_SIZE	(LVL_SIZE * LVL_DEPTH)
++
++#ifdef CONFIG_NO_HZ_COMMON
++# define NR_BASES	2
++# define BASE_STD	0
++# define BASE_DEF	1
++#else
++# define NR_BASES	1
++# define BASE_STD	0
++# define BASE_DEF	0
++#endif
++
++struct timer_base {
++	raw_spinlock_t		lock;
++	struct timer_list	*running_timer;
++#ifdef CONFIG_PREEMPT_RT_FULL
++	struct swait_queue_head	wait_for_running_timer;
++#endif
++	unsigned long		clk;
++	unsigned long		next_expiry;
++	unsigned int		cpu;
++	bool			migration_enabled;
++	bool			nohz_active;
++	bool			is_idle;
++	DECLARE_BITMAP(pending_map, WHEEL_SIZE);
++	struct hlist_head	vectors[WHEEL_SIZE];
+ } ____cacheline_aligned;
+ 
+-
+-static DEFINE_PER_CPU(struct tvec_base, tvec_bases);
++static DEFINE_PER_CPU(struct timer_base, timer_bases[NR_BASES]);
+ 
+ #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
+ unsigned int sysctl_timer_migration = 1;
+@@ -106,15 +219,17 @@ void timers_update_migration(bool update_nohz)
+ 	unsigned int cpu;
+ 
+ 	/* Avoid the loop, if nothing to update */
+-	if (this_cpu_read(tvec_bases.migration_enabled) == on)
++	if (this_cpu_read(timer_bases[BASE_STD].migration_enabled) == on)
+ 		return;
+ 
+ 	for_each_possible_cpu(cpu) {
+-		per_cpu(tvec_bases.migration_enabled, cpu) = on;
++		per_cpu(timer_bases[BASE_STD].migration_enabled, cpu) = on;
++		per_cpu(timer_bases[BASE_DEF].migration_enabled, cpu) = on;
+ 		per_cpu(hrtimer_bases.migration_enabled, cpu) = on;
+ 		if (!update_nohz)
+ 			continue;
+-		per_cpu(tvec_bases.nohz_active, cpu) = true;
++		per_cpu(timer_bases[BASE_STD].nohz_active, cpu) = true;
++		per_cpu(timer_bases[BASE_DEF].nohz_active, cpu) = true;
+ 		per_cpu(hrtimer_bases.nohz_active, cpu) = true;
+ 	}
+ }
+@@ -133,20 +248,6 @@ int timer_migration_handler(struct ctl_table *table, int write,
+ 	mutex_unlock(&mutex);
+ 	return ret;
+ }
+-
+-static inline struct tvec_base *get_target_base(struct tvec_base *base,
+-						int pinned)
+-{
+-	if (pinned || !base->migration_enabled)
+-		return this_cpu_ptr(&tvec_bases);
+-	return per_cpu_ptr(&tvec_bases, get_nohz_timer_target());
+-}
+-#else
+-static inline struct tvec_base *get_target_base(struct tvec_base *base,
+-						int pinned)
+-{
+-	return this_cpu_ptr(&tvec_bases);
+-}
+ #endif
+ 
+ static unsigned long round_jiffies_common(unsigned long j, int cpu,
+@@ -351,101 +452,126 @@ unsigned long round_jiffies_up_relative(unsigned long j)
+ }
+ EXPORT_SYMBOL_GPL(round_jiffies_up_relative);
+ 
+-/**
+- * set_timer_slack - set the allowed slack for a timer
+- * @timer: the timer to be modified
+- * @slack_hz: the amount of time (in jiffies) allowed for rounding
+- *
+- * Set the amount of time, in jiffies, that a certain timer has
+- * in terms of slack. By setting this value, the timer subsystem
+- * will schedule the actual timer somewhere between
+- * the time mod_timer() asks for, and that time plus the slack.
+- *
+- * By setting the slack to -1, a percentage of the delay is used
+- * instead.
+- */
+-void set_timer_slack(struct timer_list *timer, int slack_hz)
++
++static inline unsigned int timer_get_idx(struct timer_list *timer)
+ {
+-	timer->slack = slack_hz;
++	return (timer->flags & TIMER_ARRAYMASK) >> TIMER_ARRAYSHIFT;
++}
++
++static inline void timer_set_idx(struct timer_list *timer, unsigned int idx)
++{
++	timer->flags = (timer->flags & ~TIMER_ARRAYMASK) |
++			idx << TIMER_ARRAYSHIFT;
++}
++
++/*
++ * Helper function to calculate the array index for a given expiry
++ * time.
++ */
++static inline unsigned calc_index(unsigned expires, unsigned lvl)
++{
++	expires = (expires + LVL_GRAN(lvl)) >> LVL_SHIFT(lvl);
++	return LVL_OFFS(lvl) + (expires & LVL_MASK);
++}
++
++static int calc_wheel_index(unsigned long expires, unsigned long clk)
++{
++	unsigned long delta = expires - clk;
++	unsigned int idx;
++
++	if (delta < LVL_START(1)) {
++		idx = calc_index(expires, 0);
++	} else if (delta < LVL_START(2)) {
++		idx = calc_index(expires, 1);
++	} else if (delta < LVL_START(3)) {
++		idx = calc_index(expires, 2);
++	} else if (delta < LVL_START(4)) {
++		idx = calc_index(expires, 3);
++	} else if (delta < LVL_START(5)) {
++		idx = calc_index(expires, 4);
++	} else if (delta < LVL_START(6)) {
++		idx = calc_index(expires, 5);
++	} else if (delta < LVL_START(7)) {
++		idx = calc_index(expires, 6);
++	} else if (LVL_DEPTH > 8 && delta < LVL_START(8)) {
++		idx = calc_index(expires, 7);
++	} else if ((long) delta < 0) {
++		idx = clk & LVL_MASK;
++	} else {
++		/*
++		 * Force expire obscene large timeouts to expire at the
++		 * capacity limit of the wheel.
++		 */
++		if (expires >= WHEEL_TIMEOUT_CUTOFF)
++			expires = WHEEL_TIMEOUT_MAX;
++
++		idx = calc_index(expires, LVL_DEPTH - 1);
++	}
++	return idx;
++}
++
++/*
++ * Enqueue the timer into the hash bucket, mark it pending in
++ * the bitmap and store the index in the timer flags.
++ */
++static void enqueue_timer(struct timer_base *base, struct timer_list *timer,
++			  unsigned int idx)
++{
++	hlist_add_head(&timer->entry, base->vectors + idx);
++	__set_bit(idx, base->pending_map);
++	timer_set_idx(timer, idx);
+ }
+-EXPORT_SYMBOL_GPL(set_timer_slack);
+ 
+ static void
+-__internal_add_timer(struct tvec_base *base, struct timer_list *timer)
++__internal_add_timer(struct timer_base *base, struct timer_list *timer)
+ {
+-	unsigned long expires = timer->expires;
+-	unsigned long idx = expires - base->timer_jiffies;
+-	struct hlist_head *vec;
++	unsigned int idx;
+ 
+-	if (idx < TVR_SIZE) {
+-		int i = expires & TVR_MASK;
+-		vec = base->tv1.vec + i;
+-	} else if (idx < 1 << (TVR_BITS + TVN_BITS)) {
+-		int i = (expires >> TVR_BITS) & TVN_MASK;
+-		vec = base->tv2.vec + i;
+-	} else if (idx < 1 << (TVR_BITS + 2 * TVN_BITS)) {
+-		int i = (expires >> (TVR_BITS + TVN_BITS)) & TVN_MASK;
+-		vec = base->tv3.vec + i;
+-	} else if (idx < 1 << (TVR_BITS + 3 * TVN_BITS)) {
+-		int i = (expires >> (TVR_BITS + 2 * TVN_BITS)) & TVN_MASK;
+-		vec = base->tv4.vec + i;
+-	} else if ((signed long) idx < 0) {
+-		/*
+-		 * Can happen if you add a timer with expires == jiffies,
+-		 * or you set a timer to go off in the past
+-		 */
+-		vec = base->tv1.vec + (base->timer_jiffies & TVR_MASK);
+-	} else {
+-		int i;
+-		/* If the timeout is larger than MAX_TVAL (on 64-bit
+-		 * architectures or with CONFIG_BASE_SMALL=1) then we
+-		 * use the maximum timeout.
+-		 */
+-		if (idx > MAX_TVAL) {
+-			idx = MAX_TVAL;
+-			expires = idx + base->timer_jiffies;
+-		}
+-		i = (expires >> (TVR_BITS + 3 * TVN_BITS)) & TVN_MASK;
+-		vec = base->tv5.vec + i;
+-	}
+-
+-	hlist_add_head(&timer->entry, vec);
++	idx = calc_wheel_index(timer->expires, base->clk);
++	enqueue_timer(base, timer, idx);
+ }
+ 
+-static void internal_add_timer(struct tvec_base *base, struct timer_list *timer)
++static void
++trigger_dyntick_cpu(struct timer_base *base, struct timer_list *timer)
+ {
+-	/* Advance base->jiffies, if the base is empty */
+-	if (!base->all_timers++)
+-		base->timer_jiffies = jiffies;
+-
+-	__internal_add_timer(base, timer);
+-	/*
+-	 * Update base->active_timers and base->next_timer
+-	 */
+-	if (!(timer->flags & TIMER_DEFERRABLE)) {
+-		if (!base->active_timers++ ||
+-		    time_before(timer->expires, base->next_timer))
+-			base->next_timer = timer->expires;
+-	}
++	if (!IS_ENABLED(CONFIG_NO_HZ_COMMON) || !base->nohz_active)
++		return;
+ 
+ 	/*
+-	 * Check whether the other CPU is in dynticks mode and needs
+-	 * to be triggered to reevaluate the timer wheel.
+-	 * We are protected against the other CPU fiddling
+-	 * with the timer by holding the timer base lock. This also
+-	 * makes sure that a CPU on the way to stop its tick can not
+-	 * evaluate the timer wheel.
+-	 *
+-	 * Spare the IPI for deferrable timers on idle targets though.
+-	 * The next busy ticks will take care of it. Except full dynticks
+-	 * require special care against races with idle_cpu(), lets deal
+-	 * with that later.
++	 * This wants some optimizing similar to the below, but we do that
++	 * when we switch from push to pull for deferrable timers.
+ 	 */
+-	if (base->nohz_active) {
+-		if (!(timer->flags & TIMER_DEFERRABLE) ||
+-		    tick_nohz_full_cpu(base->cpu))
++	if (timer->flags & TIMER_DEFERRABLE) {
++		if (tick_nohz_full_cpu(base->cpu))
+ 			wake_up_nohz_cpu(base->cpu);
++		return;
+ 	}
++
++	/*
++	 * We might have to IPI the remote CPU if the base is idle and the
++	 * timer is not deferrable. If the other cpu is on the way to idle
++	 * then it can't set base->is_idle as we hold base lock.
++	 */
++	if (!base->is_idle)
++		return;
++
++	/* Check whether this is the new first expiring timer */
++	if (time_after_eq(timer->expires, base->next_expiry))
++		return;
++
++	/*
++	 * Set the next expiry time and kick the cpu so it can reevaluate the
++	 * wheel
++	 */
++	base->next_expiry = timer->expires;
++		wake_up_nohz_cpu(base->cpu);
++}
++
++static void
++internal_add_timer(struct timer_base *base, struct timer_list *timer)
++{
++	__internal_add_timer(base, timer);
++	trigger_dyntick_cpu(base, timer);
+ }
+ 
+ #ifdef CONFIG_TIMER_STATS
+@@ -681,7 +807,6 @@ static void do_init_timer(struct timer_list *timer, unsigned int flags,
+ {
+ 	timer->entry.pprev = NULL;
+ 	timer->flags = flags | raw_smp_processor_id();
+-	timer->slack = -1;
+ #ifdef CONFIG_TIMER_STATS
+ 	timer->start_site = NULL;
+ 	timer->start_pid = -1;
+@@ -721,71 +846,170 @@ static inline void detach_timer(struct timer_list *timer, bool clear_pending)
+ 	entry->next = LIST_POISON2;
+ }
+ 
+-static inline void
+-detach_expired_timer(struct timer_list *timer, struct tvec_base *base)
+-{
+-	detach_timer(timer, true);
+-	if (!(timer->flags & TIMER_DEFERRABLE))
+-		base->active_timers--;
+-	base->all_timers--;
+-}
+-
+-static int detach_if_pending(struct timer_list *timer, struct tvec_base *base,
++static int detach_if_pending(struct timer_list *timer, struct timer_base *base,
+ 			     bool clear_pending)
+ {
++	unsigned idx = timer_get_idx(timer);
++
+ 	if (!timer_pending(timer))
+ 		return 0;
+ 
++	if (hlist_is_singular_node(&timer->entry, base->vectors + idx))
++		__clear_bit(idx, base->pending_map);
++
+ 	detach_timer(timer, clear_pending);
+-	if (!(timer->flags & TIMER_DEFERRABLE)) {
+-		base->active_timers--;
+-		if (timer->expires == base->next_timer)
+-			base->next_timer = base->timer_jiffies;
+-	}
+-	/* If this was the last timer, advance base->jiffies */
+-	if (!--base->all_timers)
+-		base->timer_jiffies = jiffies;
+ 	return 1;
+ }
+ 
++static inline struct timer_base *get_timer_cpu_base(u32 tflags, u32 cpu)
++{
++	struct timer_base *base = per_cpu_ptr(&timer_bases[BASE_STD], cpu);
++
++	/*
++	 * If the timer is deferrable and nohz is active then we need to use
++	 * the deferrable base.
++	 */
++	if (IS_ENABLED(CONFIG_NO_HZ_COMMON) && base->nohz_active &&
++	    (tflags & TIMER_DEFERRABLE))
++		base = per_cpu_ptr(&timer_bases[BASE_DEF], cpu);
++	return base;
++}
++
++static inline struct timer_base *get_timer_this_cpu_base(u32 tflags)
++{
++	struct timer_base *base = this_cpu_ptr(&timer_bases[BASE_STD]);
++
++	/*
++	 * If the timer is deferrable and nohz is active then we need to use
++	 * the deferrable base.
++	 */
++	if (IS_ENABLED(CONFIG_NO_HZ_COMMON) && base->nohz_active &&
++	    (tflags & TIMER_DEFERRABLE))
++		base = this_cpu_ptr(&timer_bases[BASE_DEF]);
++	return base;
++}
++
++static inline struct timer_base *get_timer_base(u32 tflags)
++{
++	return get_timer_cpu_base(tflags, tflags & TIMER_CPUMASK);
++}
++
++#ifdef CONFIG_NO_HZ_COMMON
++static inline struct timer_base *__get_target_base(struct timer_base *base,
++						   unsigned tflags)
++{
++#ifdef CONFIG_SMP
++	if ((tflags & TIMER_PINNED) || !base->migration_enabled)
++		return get_timer_this_cpu_base(tflags);
++	return get_timer_cpu_base(tflags, get_nohz_timer_target());
++#else
++	return get_timer_this_cpu_base(tflags);
++#endif
++}
++
++static inline void forward_timer_base(struct timer_base *base)
++{
++	/*
++	 * We only forward the base when it's idle and we have a delta between
++	 * base clock and jiffies.
++	 */
++	if (!base->is_idle || (long) (jiffies - base->clk) < 2)
++		return;
++
++	/*
++	 * If the next expiry value is > jiffies, then we fast forward to
++	 * jiffies otherwise we forward to the next expiry value.
++	 */
++	if (time_after(base->next_expiry, jiffies))
++		base->clk = jiffies;
++	else
++		base->clk = base->next_expiry;
++}
++#else
++static inline struct timer_base *__get_target_base(struct timer_base *base,
++						   unsigned tflags)
++{
++	return get_timer_this_cpu_base(tflags);
++}
++
++static inline void forward_timer_base(struct timer_base *base) { }
++#endif
++
++static inline struct timer_base *get_target_base(struct timer_base *base,
++						 unsigned tflags)
++{
++	struct timer_base *target = __get_target_base(base, tflags);
++
++	forward_timer_base(target);
++	return target;
++}
++
+ /*
+- * We are using hashed locking: holding per_cpu(tvec_bases).lock
+- * means that all timers which are tied to this base via timer->base are
+- * locked, and the base itself is locked too.
++ * We are using hashed locking: Holding per_cpu(timer_bases[x]).lock means
++ * that all timers which are tied to this base are locked, and the base itself
++ * is locked too.
+  *
+  * So __run_timers/migrate_timers can safely modify all timers which could
+- * be found on ->tvX lists.
++ * be found in the base->vectors array.
+  *
+- * When the timer's base is locked and removed from the list, the
+- * TIMER_MIGRATING flag is set, FIXME
++ * When a timer is migrating then the TIMER_MIGRATING flag is set and we need
++ * to wait until the migration is done.
+  */
+-static struct tvec_base *lock_timer_base(struct timer_list *timer,
+-					unsigned long *flags)
++static struct timer_base *lock_timer_base(struct timer_list *timer,
++					  unsigned long *flags)
+ 	__acquires(timer->base->lock)
+ {
+ 	for (;;) {
++		struct timer_base *base;
+ 		u32 tf = timer->flags;
+-		struct tvec_base *base;
+ 
+ 		if (!(tf & TIMER_MIGRATING)) {
+-			base = per_cpu_ptr(&tvec_bases, tf & TIMER_CPUMASK);
+-			spin_lock_irqsave(&base->lock, *flags);
++			base = get_timer_base(tf);
++			raw_spin_lock_irqsave(&base->lock, *flags);
+ 			if (timer->flags == tf)
+ 				return base;
+-			spin_unlock_irqrestore(&base->lock, *flags);
++			raw_spin_unlock_irqrestore(&base->lock, *flags);
+ 		}
+ 		cpu_relax();
+ 	}
+ }
+ 
+ static inline int
+-__mod_timer(struct timer_list *timer, unsigned long expires,
+-	    bool pending_only, int pinned)
++__mod_timer(struct timer_list *timer, unsigned long expires, bool pending_only)
+ {
+-	struct tvec_base *base, *new_base;
+-	unsigned long flags;
++	struct timer_base *base, *new_base;
++	unsigned int idx = UINT_MAX;
++	unsigned long clk = 0, flags;
+ 	int ret = 0;
+ 
++	/*
++	 * This is a common optimization triggered by the networking code - if
++	 * the timer is re-modified to be the same thing or ends up in the
++	 * same array bucket then just return:
++	 */
++	if (timer_pending(timer)) {
++		if (timer->expires == expires)
++			return 1;
++		/*
++		 * Take the current timer_jiffies of base, but without holding
++		 * the lock!
++		 */
++		base = get_timer_base(timer->flags);
++		clk = base->clk;
++
++		idx = calc_wheel_index(expires, clk);
++
++		/*
++		 * Retrieve and compare the array index of the pending
++		 * timer. If it matches set the expiry to the new value so a
++		 * subsequent call will exit in the expires check above.
++		 */
++		if (idx == timer_get_idx(timer)) {
++			timer->expires = expires;
++			return 1;
++		}
++	}
++
+ 	timer_stats_timer_set_start_info(timer);
+ 	BUG_ON(!timer->function);
+ 
+@@ -797,33 +1021,44 @@ __mod_timer(struct timer_list *timer, unsigned long expires,
+ 
+ 	debug_activate(timer, expires);
+ 
+-	new_base = get_target_base(base, pinned);
++	new_base = get_target_base(base, timer->flags);
+ 
+ 	if (base != new_base) {
+ 		/*
+-		 * We are trying to schedule the timer on the local CPU.
++		 * We are trying to schedule the timer on the new base.
+ 		 * However we can't change timer's base while it is running,
+ 		 * otherwise del_timer_sync() can't detect that the timer's
+-		 * handler yet has not finished. This also guarantees that
+-		 * the timer is serialized wrt itself.
++		 * handler yet has not finished. This also guarantees that the
++		 * timer is serialized wrt itself.
+ 		 */
+ 		if (likely(base->running_timer != timer)) {
+ 			/* See the comment in lock_timer_base() */
+ 			timer->flags |= TIMER_MIGRATING;
+ 
+-			spin_unlock(&base->lock);
++			raw_spin_unlock(&base->lock);
+ 			base = new_base;
+-			spin_lock(&base->lock);
++			raw_spin_lock(&base->lock);
+ 			WRITE_ONCE(timer->flags,
+ 				   (timer->flags & ~TIMER_BASEMASK) | base->cpu);
+ 		}
+ 	}
+ 
+ 	timer->expires = expires;
+-	internal_add_timer(base, timer);
++	/*
++	 * If idx was calculated above and the base time did not advance
++	 * between calculating idx and taking the lock, only enqueue_timer()
++	 * and trigger_dyntick_cpu() is required. Otherwise we need to
++	 * (re)calculate the wheel index via internal_add_timer().
++	 */
++	if (idx != UINT_MAX && clk == base->clk) {
++		enqueue_timer(base, timer, idx);
++		trigger_dyntick_cpu(base, timer);
++	} else {
++		internal_add_timer(base, timer);
++	}
+ 
+ out_unlock:
+-	spin_unlock_irqrestore(&base->lock, flags);
++	raw_spin_unlock_irqrestore(&base->lock, flags);
+ 
+ 	return ret;
+ }
+@@ -840,49 +1075,10 @@ __mod_timer(struct timer_list *timer, unsigned long expires,
+  */
+ int mod_timer_pending(struct timer_list *timer, unsigned long expires)
+ {
+-	return __mod_timer(timer, expires, true, TIMER_NOT_PINNED);
++	return __mod_timer(timer, expires, true);
+ }
+ EXPORT_SYMBOL(mod_timer_pending);
+ 
+-/*
+- * Decide where to put the timer while taking the slack into account
+- *
+- * Algorithm:
+- *   1) calculate the maximum (absolute) time
+- *   2) calculate the highest bit where the expires and new max are different
+- *   3) use this bit to make a mask
+- *   4) use the bitmask to round down the maximum time, so that all last
+- *      bits are zeros
+- */
+-static inline
+-unsigned long apply_slack(struct timer_list *timer, unsigned long expires)
+-{
+-	unsigned long expires_limit, mask;
+-	int bit;
+-
+-	if (timer->slack >= 0) {
+-		expires_limit = expires + timer->slack;
+-	} else {
+-		long delta = expires - jiffies;
+-
+-		if (delta < 256)
+-			return expires;
+-
+-		expires_limit = expires + delta / 256;
+-	}
+-	mask = expires ^ expires_limit;
+-	if (mask == 0)
+-		return expires;
+-
+-	bit = __fls(mask);
+-
+-	mask = (1UL << bit) - 1;
+-
+-	expires_limit = expires_limit & ~(mask);
+-
+-	return expires_limit;
+-}
+-
+ /**
+  * mod_timer - modify a timer's timeout
+  * @timer: the timer to be modified
+@@ -905,49 +1101,11 @@ unsigned long apply_slack(struct timer_list *timer, unsigned long expires)
+  */
+ int mod_timer(struct timer_list *timer, unsigned long expires)
+ {
+-	expires = apply_slack(timer, expires);
+-
+-	/*
+-	 * This is a common optimization triggered by the
+-	 * networking code - if the timer is re-modified
+-	 * to be the same thing then just return:
+-	 */
+-	if (timer_pending(timer) && timer->expires == expires)
+-		return 1;
+-
+-	return __mod_timer(timer, expires, false, TIMER_NOT_PINNED);
++	return __mod_timer(timer, expires, false);
+ }
+ EXPORT_SYMBOL(mod_timer);
+ 
+ /**
+- * mod_timer_pinned - modify a timer's timeout
+- * @timer: the timer to be modified
+- * @expires: new timeout in jiffies
+- *
+- * mod_timer_pinned() is a way to update the expire field of an
+- * active timer (if the timer is inactive it will be activated)
+- * and to ensure that the timer is scheduled on the current CPU.
+- *
+- * Note that this does not prevent the timer from being migrated
+- * when the current CPU goes offline.  If this is a problem for
+- * you, use CPU-hotplug notifiers to handle it correctly, for
+- * example, cancelling the timer when the corresponding CPU goes
+- * offline.
+- *
+- * mod_timer_pinned(timer, expires) is equivalent to:
+- *
+- *     del_timer(timer); timer->expires = expires; add_timer(timer);
+- */
+-int mod_timer_pinned(struct timer_list *timer, unsigned long expires)
+-{
+-	if (timer->expires == expires && timer_pending(timer))
+-		return 1;
+-
+-	return __mod_timer(timer, expires, false, TIMER_PINNED);
+-}
+-EXPORT_SYMBOL(mod_timer_pinned);
+-
+-/**
+  * add_timer - start a timer
+  * @timer: the timer to be added
+  *
+@@ -977,13 +1135,14 @@ EXPORT_SYMBOL(add_timer);
+  */
+ void add_timer_on(struct timer_list *timer, int cpu)
+ {
+-	struct tvec_base *new_base = per_cpu_ptr(&tvec_bases, cpu);
+-	struct tvec_base *base;
++	struct timer_base *new_base, *base;
+ 	unsigned long flags;
+ 
+ 	timer_stats_timer_set_start_info(timer);
+ 	BUG_ON(timer_pending(timer) || !timer->function);
+ 
++	new_base = get_timer_cpu_base(timer->flags, cpu);
++
+ 	/*
+ 	 * If @timer was on a different CPU, it should be migrated with the
+ 	 * old base locked to prevent other operations proceeding with the
+@@ -993,19 +1152,46 @@ void add_timer_on(struct timer_list *timer, int cpu)
+ 	if (base != new_base) {
+ 		timer->flags |= TIMER_MIGRATING;
+ 
+-		spin_unlock(&base->lock);
++		raw_spin_unlock(&base->lock);
+ 		base = new_base;
+-		spin_lock(&base->lock);
++		raw_spin_lock(&base->lock);
+ 		WRITE_ONCE(timer->flags,
+ 			   (timer->flags & ~TIMER_BASEMASK) | cpu);
+ 	}
+ 
+ 	debug_activate(timer, timer->expires);
+ 	internal_add_timer(base, timer);
+-	spin_unlock_irqrestore(&base->lock, flags);
++	raw_spin_unlock_irqrestore(&base->lock, flags);
+ }
+ EXPORT_SYMBOL_GPL(add_timer_on);
+ 
++#ifdef CONFIG_PREEMPT_RT_FULL
++/*
++ * Wait for a running timer
++ */
++static void wait_for_running_timer(struct timer_list *timer)
++{
++	struct timer_base *base;
++	u32 tf = timer->flags;
++
++	if (tf & TIMER_MIGRATING)
++		return;
++
++	base = get_timer_base(tf);
++	swait_event(base->wait_for_running_timer,
++		   base->running_timer != timer);
++}
++
++# define wakeup_timer_waiters(b)	swake_up_all(&(b)->wait_for_running_timer)
++#else
++static inline void wait_for_running_timer(struct timer_list *timer)
++{
++	cpu_relax();
++}
++
++# define wakeup_timer_waiters(b)	do { } while (0)
++#endif
++
+ /**
+  * del_timer - deactive a timer.
+  * @timer: the timer to be deactivated
+@@ -1019,7 +1205,7 @@ EXPORT_SYMBOL_GPL(add_timer_on);
+  */
+ int del_timer(struct timer_list *timer)
+ {
+-	struct tvec_base *base;
++	struct timer_base *base;
+ 	unsigned long flags;
+ 	int ret = 0;
+ 
+@@ -1029,7 +1215,7 @@ int del_timer(struct timer_list *timer)
+ 	if (timer_pending(timer)) {
+ 		base = lock_timer_base(timer, &flags);
+ 		ret = detach_if_pending(timer, base, true);
+-		spin_unlock_irqrestore(&base->lock, flags);
++		raw_spin_unlock_irqrestore(&base->lock, flags);
+ 	}
+ 
+ 	return ret;
+@@ -1045,7 +1231,7 @@ EXPORT_SYMBOL(del_timer);
+  */
+ int try_to_del_timer_sync(struct timer_list *timer)
+ {
+-	struct tvec_base *base;
++	struct timer_base *base;
+ 	unsigned long flags;
+ 	int ret = -1;
+ 
+@@ -1057,13 +1243,13 @@ int try_to_del_timer_sync(struct timer_list *timer)
+ 		timer_stats_timer_clear_start_info(timer);
+ 		ret = detach_if_pending(timer, base, true);
+ 	}
+-	spin_unlock_irqrestore(&base->lock, flags);
++	raw_spin_unlock_irqrestore(&base->lock, flags);
+ 
+ 	return ret;
+ }
+ EXPORT_SYMBOL(try_to_del_timer_sync);
+ 
+-#ifdef CONFIG_SMP
++#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT_FULL)
+ /**
+  * del_timer_sync - deactivate a timer and wait for the handler to finish.
+  * @timer: the timer to be deactivated
+@@ -1123,33 +1309,12 @@ int del_timer_sync(struct timer_list *timer)
+ 		int ret = try_to_del_timer_sync(timer);
+ 		if (ret >= 0)
+ 			return ret;
+-		cpu_relax();
++		wait_for_running_timer(timer);
+ 	}
+ }
+ EXPORT_SYMBOL(del_timer_sync);
+ #endif
+ 
+-static int cascade(struct tvec_base *base, struct tvec *tv, int index)
+-{
+-	/* cascade all the timers from tv up one level */
+-	struct timer_list *timer;
+-	struct hlist_node *tmp;
+-	struct hlist_head tv_list;
+-
+-	hlist_move_list(tv->vec + index, &tv_list);
+-
+-	/*
+-	 * We are removing _all_ timers from the list, so we
+-	 * don't have to detach them individually.
+-	 */
+-	hlist_for_each_entry_safe(timer, tmp, &tv_list, entry) {
+-		/* No accounting, while moving them */
+-		__internal_add_timer(base, timer);
+-	}
+-
+-	return index;
+-}
+-
+ static void call_timer_fn(struct timer_list *timer, void (*fn)(unsigned long),
+ 			  unsigned long data)
+ {
+@@ -1193,147 +1358,144 @@ static void call_timer_fn(struct timer_list *timer, void (*fn)(unsigned long),
+ 	}
+ }
+ 
+-#define INDEX(N) ((base->timer_jiffies >> (TVR_BITS + (N) * TVN_BITS)) & TVN_MASK)
+-
+-/**
+- * __run_timers - run all expired timers (if any) on this CPU.
+- * @base: the timer vector to be processed.
+- *
+- * This function cascades all vectors and executes all expired timer
+- * vectors.
+- */
+-static inline void __run_timers(struct tvec_base *base)
++static void expire_timers(struct timer_base *base, struct hlist_head *head)
+ {
+-	struct timer_list *timer;
++	while (!hlist_empty(head)) {
++		struct timer_list *timer;
++		void (*fn)(unsigned long);
++		unsigned long data;
+ 
+-	spin_lock_irq(&base->lock);
++		timer = hlist_entry(head->first, struct timer_list, entry);
++		timer_stats_account_timer(timer);
+ 
+-	while (time_after_eq(jiffies, base->timer_jiffies)) {
+-		struct hlist_head work_list;
+-		struct hlist_head *head = &work_list;
+-		int index;
++		base->running_timer = timer;
++		detach_timer(timer, true);
+ 
+-		if (!base->all_timers) {
+-			base->timer_jiffies = jiffies;
+-			break;
+-		}
++		fn = timer->function;
++		data = timer->data;
+ 
+-		index = base->timer_jiffies & TVR_MASK;
+-
+-		/*
+-		 * Cascade timers:
+-		 */
+-		if (!index &&
+-			(!cascade(base, &base->tv2, INDEX(0))) &&
+-				(!cascade(base, &base->tv3, INDEX(1))) &&
+-					!cascade(base, &base->tv4, INDEX(2)))
+-			cascade(base, &base->tv5, INDEX(3));
+-		++base->timer_jiffies;
+-		hlist_move_list(base->tv1.vec + index, head);
+-		while (!hlist_empty(head)) {
+-			void (*fn)(unsigned long);
+-			unsigned long data;
+-			bool irqsafe;
+-
+-			timer = hlist_entry(head->first, struct timer_list, entry);
+-			fn = timer->function;
+-			data = timer->data;
+-			irqsafe = timer->flags & TIMER_IRQSAFE;
+-
+-			timer_stats_account_timer(timer);
+-
+-			base->running_timer = timer;
+-			detach_expired_timer(timer, base);
+-
+-			if (irqsafe) {
+-				spin_unlock(&base->lock);
+-				call_timer_fn(timer, fn, data);
+-				spin_lock(&base->lock);
+-			} else {
+-				spin_unlock_irq(&base->lock);
+-				call_timer_fn(timer, fn, data);
+-				spin_lock_irq(&base->lock);
+-			}
++		if (!IS_ENABLED(CONFIG_PREEMPT_RT_FULL) &&
++		    timer->flags & TIMER_IRQSAFE) {
++			raw_spin_unlock(&base->lock);
++			call_timer_fn(timer, fn, data);
++			base->running_timer = NULL;
++			raw_spin_lock(&base->lock);
++		} else {
++			raw_spin_unlock_irq(&base->lock);
++			call_timer_fn(timer, fn, data);
++			base->running_timer = NULL;
++			raw_spin_lock_irq(&base->lock);
+ 		}
+ 	}
+-	base->running_timer = NULL;
+-	spin_unlock_irq(&base->lock);
++}
++
++static int __collect_expired_timers(struct timer_base *base,
++				    struct hlist_head *heads)
++{
++	unsigned long clk = base->clk;
++	struct hlist_head *vec;
++	int i, levels = 0;
++	unsigned int idx;
++
++	for (i = 0; i < LVL_DEPTH; i++) {
++		idx = (clk & LVL_MASK) + i * LVL_SIZE;
++
++		if (__test_and_clear_bit(idx, base->pending_map)) {
++			vec = base->vectors + idx;
++			hlist_move_list(vec, heads++);
++			levels++;
++		}
++		/* Is it time to look at the next level? */
++		if (clk & LVL_CLK_MASK)
++			break;
++		/* Shift clock for the next level granularity */
++		clk >>= LVL_CLK_SHIFT;
++	}
++	return levels;
+ }
+ 
+ #ifdef CONFIG_NO_HZ_COMMON
+ /*
+- * Find out when the next timer event is due to happen. This
+- * is used on S/390 to stop all activity when a CPU is idle.
+- * This function needs to be called with interrupts disabled.
++ * Find the next pending bucket of a level. Search from level start (@offset)
++ * + @clk upwards and if nothing there, search from start of the level
++ * (@offset) up to @offset + clk.
+  */
+-static unsigned long __next_timer_interrupt(struct tvec_base *base)
++static int next_pending_bucket(struct timer_base *base, unsigned offset,
++			       unsigned clk)
+ {
+-	unsigned long timer_jiffies = base->timer_jiffies;
+-	unsigned long expires = timer_jiffies + NEXT_TIMER_MAX_DELTA;
+-	int index, slot, array, found = 0;
+-	struct timer_list *nte;
+-	struct tvec *varray[4];
++	unsigned pos, start = offset + clk;
++	unsigned end = offset + LVL_SIZE;
+ 
+-	/* Look for timer events in tv1. */
+-	index = slot = timer_jiffies & TVR_MASK;
+-	do {
+-		hlist_for_each_entry(nte, base->tv1.vec + slot, entry) {
+-			if (nte->flags & TIMER_DEFERRABLE)
+-				continue;
++	pos = find_next_bit(base->pending_map, end, start);
++	if (pos < end)
++		return pos - start;
+ 
+-			found = 1;
+-			expires = nte->expires;
+-			/* Look at the cascade bucket(s)? */
+-			if (!index || slot < index)
+-				goto cascade;
+-			return expires;
++	pos = find_next_bit(base->pending_map, start, offset);
++	return pos < start ? pos + LVL_SIZE - start : -1;
++}
++
++/*
++ * Search the first expiring timer in the various clock levels. Caller must
++ * hold base->lock.
++ */
++static unsigned long __next_timer_interrupt(struct timer_base *base)
++{
++	unsigned long clk, next, adj;
++	unsigned lvl, offset = 0;
++
++	next = base->clk + NEXT_TIMER_MAX_DELTA;
++	clk = base->clk;
++	for (lvl = 0; lvl < LVL_DEPTH; lvl++, offset += LVL_SIZE) {
++		int pos = next_pending_bucket(base, offset, clk & LVL_MASK);
++
++		if (pos >= 0) {
++			unsigned long tmp = clk + (unsigned long) pos;
++
++			tmp <<= LVL_SHIFT(lvl);
++			if (time_before(tmp, next))
++				next = tmp;
+ 		}
+-		slot = (slot + 1) & TVR_MASK;
+-	} while (slot != index);
+-
+-cascade:
+-	/* Calculate the next cascade event */
+-	if (index)
+-		timer_jiffies += TVR_SIZE - index;
+-	timer_jiffies >>= TVR_BITS;
+-
+-	/* Check tv2-tv5. */
+-	varray[0] = &base->tv2;
+-	varray[1] = &base->tv3;
+-	varray[2] = &base->tv4;
+-	varray[3] = &base->tv5;
+-
+-	for (array = 0; array < 4; array++) {
+-		struct tvec *varp = varray[array];
+-
+-		index = slot = timer_jiffies & TVN_MASK;
+-		do {
+-			hlist_for_each_entry(nte, varp->vec + slot, entry) {
+-				if (nte->flags & TIMER_DEFERRABLE)
+-					continue;
+-
+-				found = 1;
+-				if (time_before(nte->expires, expires))
+-					expires = nte->expires;
+-			}
+-			/*
+-			 * Do we still search for the first timer or are
+-			 * we looking up the cascade buckets ?
+-			 */
+-			if (found) {
+-				/* Look at the cascade bucket(s)? */
+-				if (!index || slot < index)
+-					break;
+-				return expires;
+-			}
+-			slot = (slot + 1) & TVN_MASK;
+-		} while (slot != index);
+-
+-		if (index)
+-			timer_jiffies += TVN_SIZE - index;
+-		timer_jiffies >>= TVN_BITS;
++		/*
++		 * Clock for the next level. If the current level clock lower
++		 * bits are zero, we look at the next level as is. If not we
++		 * need to advance it by one because that's going to be the
++		 * next expiring bucket in that level. base->clk is the next
++		 * expiring jiffie. So in case of:
++		 *
++		 * LVL5 LVL4 LVL3 LVL2 LVL1 LVL0
++		 *  0    0    0    0    0    0
++		 *
++		 * we have to look at all levels @index 0. With
++		 *
++		 * LVL5 LVL4 LVL3 LVL2 LVL1 LVL0
++		 *  0    0    0    0    0    2
++		 *
++		 * LVL0 has the next expiring bucket @index 2. The upper
++		 * levels have the next expiring bucket @index 1.
++		 *
++		 * In case that the propagation wraps the next level the same
++		 * rules apply:
++		 *
++		 * LVL5 LVL4 LVL3 LVL2 LVL1 LVL0
++		 *  0    0    0    0    F    2
++		 *
++		 * So after looking at LVL0 we get:
++		 *
++		 * LVL5 LVL4 LVL3 LVL2 LVL1
++		 *  0    0    0    1    0
++		 *
++		 * So no propagation from LVL1 to LVL2 because that happened
++		 * with the add already, but then we need to propagate further
++		 * from LVL2 to LVL3.
++		 *
++		 * So the simple check whether the lower bits of the current
++		 * level are 0 or not is sufficient for all cases.
++		 */
++		adj = clk & LVL_CLK_MASK ? 1 : 0;
++		clk >>= LVL_CLK_SHIFT;
++		clk += adj;
+ 	}
+-	return expires;
++	return next;
+ }
+ 
+ /*
+@@ -1379,7 +1541,7 @@ static u64 cmp_next_hrtimer_event(u64 basem, u64 expires)
+  */
+ u64 get_next_timer_interrupt(unsigned long basej, u64 basem)
+ {
+-	struct tvec_base *base = this_cpu_ptr(&tvec_bases);
++	struct timer_base *base = this_cpu_ptr(&timer_bases[BASE_STD]);
+ 	u64 expires = KTIME_MAX;
+ 	unsigned long nextevt;
+ 
+@@ -1390,20 +1552,81 @@ u64 get_next_timer_interrupt(unsigned long basej, u64 basem)
+ 	if (cpu_is_offline(smp_processor_id()))
+ 		return expires;
+ 
+-	spin_lock(&base->lock);
+-	if (base->active_timers) {
+-		if (time_before_eq(base->next_timer, base->timer_jiffies))
+-			base->next_timer = __next_timer_interrupt(base);
+-		nextevt = base->next_timer;
+-		if (time_before_eq(nextevt, basej))
+-			expires = basem;
+-		else
+-			expires = basem + (nextevt - basej) * TICK_NSEC;
++	raw_spin_lock(&base->lock);
++	nextevt = __next_timer_interrupt(base);
++	base->next_expiry = nextevt;
++	/*
++	 * We have a fresh next event. Check whether we can forward the base.
++	 */
++	if (time_after(nextevt, jiffies))
++		base->clk = jiffies;
++	else if (time_after(nextevt, base->clk))
++		base->clk = nextevt;
++
++	if (time_before_eq(nextevt, basej)) {
++		expires = basem;
++		base->is_idle = false;
++	} else {
++		expires = basem + (nextevt - basej) * TICK_NSEC;
++		/*
++		 * If we expect to sleep more than a tick, mark the base idle.
++		 */
++		if ((expires - basem) > TICK_NSEC)
++			base->is_idle = true;
+ 	}
+-	spin_unlock(&base->lock);
++	raw_spin_unlock(&base->lock);
+ 
+ 	return cmp_next_hrtimer_event(basem, expires);
+ }
++
++/**
++ * timer_clear_idle - Clear the idle state of the timer base
++ *
++ * Called with interrupts disabled
++ */
++void timer_clear_idle(void)
++{
++	struct timer_base *base = this_cpu_ptr(&timer_bases[BASE_STD]);
++
++	/*
++	 * We do this unlocked. The worst outcome is a remote enqueue sending
++	 * a pointless IPI, but taking the lock would just make the window for
++	 * sending the IPI a few instructions smaller for the cost of taking
++	 * the lock in the exit from idle path.
++	 */
++	base->is_idle = false;
++}
++
++static int collect_expired_timers(struct timer_base *base,
++				  struct hlist_head *heads)
++{
++	/*
++	 * NOHZ optimization. After a long idle sleep we need to forward the
++	 * base to current jiffies. Avoid a loop by searching the bitfield for
++	 * the next expiring timer.
++	 */
++	if ((long)(jiffies - base->clk) > 2) {
++		unsigned long next = __next_timer_interrupt(base);
++
++		/*
++		 * If the next timer is ahead of time forward to current
++		 * jiffies, otherwise forward to the next expiry time.
++		 */
++		if (time_after(next, jiffies)) {
++			/* The call site will increment clock! */
++			base->clk = jiffies - 1;
++			return 0;
++		}
++		base->clk = next;
++	}
++	return __collect_expired_timers(base, heads);
++}
++#else
++static inline int collect_expired_timers(struct timer_base *base,
++					 struct hlist_head *heads)
++{
++	return __collect_expired_timers(base, heads);
++}
+ #endif
+ 
+ /*
+@@ -1416,25 +1639,54 @@ void update_process_times(int user_tick)
+ 
+ 	/* Note: this timer irq context must be accounted for as well. */
+ 	account_process_tick(p, user_tick);
++	scheduler_tick();
+ 	run_local_timers();
+ 	rcu_check_callbacks(user_tick);
+-#ifdef CONFIG_IRQ_WORK
++#if defined(CONFIG_IRQ_WORK)
+ 	if (in_irq())
+ 		irq_work_tick();
+ #endif
+-	scheduler_tick();
+ 	run_posix_cpu_timers(p);
+ }
+ 
++/**
++ * __run_timers - run all expired timers (if any) on this CPU.
++ * @base: the timer vector to be processed.
++ */
++static inline void __run_timers(struct timer_base *base)
++{
++	struct hlist_head heads[LVL_DEPTH];
++	int levels;
++
++	if (!time_after_eq(jiffies, base->clk))
++		return;
++
++	raw_spin_lock_irq(&base->lock);
++
++	while (time_after_eq(jiffies, base->clk)) {
++
++		levels = collect_expired_timers(base, heads);
++		base->clk++;
++
++		while (levels--)
++			expire_timers(base, heads + levels);
++	}
++	raw_spin_unlock_irq(&base->lock);
++	wakeup_timer_waiters(base);
++}
++
+ /*
+  * This function runs timers and the timer-tq in bottom half context.
+  */
+ static void run_timer_softirq(struct softirq_action *h)
+ {
+-	struct tvec_base *base = this_cpu_ptr(&tvec_bases);
++	struct timer_base *base = this_cpu_ptr(&timer_bases[BASE_STD]);
+ 
+-	if (time_after_eq(jiffies, base->timer_jiffies))
+-		__run_timers(base);
++	irq_work_tick_soft();
++
++	__run_timers(base);
++	if (IS_ENABLED(CONFIG_NO_HZ_COMMON) && base->nohz_active)
++		__run_timers(this_cpu_ptr(&timer_bases[BASE_DEF]));
+ }
+ 
+ /*
+@@ -1442,7 +1694,18 @@ static void run_timer_softirq(struct softirq_action *h)
+  */
+ void run_local_timers(void)
+ {
++	struct timer_base *base = this_cpu_ptr(&timer_bases[BASE_STD]);
++
+ 	hrtimer_run_queues();
++	/* Raise the softirq only if required. */
++	if (time_before(jiffies, base->clk)) {
++		if (!IS_ENABLED(CONFIG_NO_HZ_COMMON) || !base->nohz_active)
++			return;
++		/* CPU is awake, so check the deferrable base. */
++		base++;
++		if (time_before(jiffies, base->clk))
++			return;
++	}
+ 	raise_softirq(TIMER_SOFTIRQ);
+ }
+ 
+@@ -1527,7 +1790,7 @@ signed long __sched schedule_timeout(signed long timeout)
+ 	expire = timeout + jiffies;
+ 
+ 	setup_timer_on_stack(&timer, process_timeout, (unsigned long)current);
+-	__mod_timer(&timer, expire, false, TIMER_NOT_PINNED);
++	__mod_timer(&timer, expire, false);
+ 	schedule();
+ 	del_singleshot_timer_sync(&timer);
+ 
+@@ -1578,14 +1841,13 @@ signed long __sched schedule_timeout_idle(signed long timeout)
+ EXPORT_SYMBOL(schedule_timeout_idle);
+ 
+ #ifdef CONFIG_HOTPLUG_CPU
+-static void migrate_timer_list(struct tvec_base *new_base, struct hlist_head *head)
++static void migrate_timer_list(struct timer_base *new_base, struct hlist_head *head)
+ {
+ 	struct timer_list *timer;
+ 	int cpu = new_base->cpu;
+ 
+ 	while (!hlist_empty(head)) {
+ 		timer = hlist_entry(head->first, struct timer_list, entry);
+-		/* We ignore the accounting on the dying cpu */
+ 		detach_timer(timer, false);
+ 		timer->flags = (timer->flags & ~TIMER_BASEMASK) | cpu;
+ 		internal_add_timer(new_base, timer);
+@@ -1594,37 +1856,31 @@ static void migrate_timer_list(struct tvec_base *new_base, struct hlist_head *he
+ 
+ static void migrate_timers(int cpu)
+ {
+-	struct tvec_base *old_base;
+-	struct tvec_base *new_base;
+-	int i;
++	struct timer_base *old_base;
++	struct timer_base *new_base;
++	int b, i;
+ 
+ 	BUG_ON(cpu_online(cpu));
+-	old_base = per_cpu_ptr(&tvec_bases, cpu);
+-	new_base = get_cpu_ptr(&tvec_bases);
+-	/*
+-	 * The caller is globally serialized and nobody else
+-	 * takes two locks at once, deadlock is not possible.
+-	 */
+-	spin_lock_irq(&new_base->lock);
+-	spin_lock_nested(&old_base->lock, SINGLE_DEPTH_NESTING);
+ 
+-	BUG_ON(old_base->running_timer);
++	for (b = 0; b < NR_BASES; b++) {
++		old_base = per_cpu_ptr(&timer_bases[b], cpu);
++		new_base = get_cpu_ptr(&timer_bases[b]);
++		/*
++		 * The caller is globally serialized and nobody else
++		 * takes two locks at once, deadlock is not possible.
++		 */
++		raw_spin_lock_irq(&new_base->lock);
++		raw_spin_lock_nested(&old_base->lock, SINGLE_DEPTH_NESTING);
+ 
+-	for (i = 0; i < TVR_SIZE; i++)
+-		migrate_timer_list(new_base, old_base->tv1.vec + i);
+-	for (i = 0; i < TVN_SIZE; i++) {
+-		migrate_timer_list(new_base, old_base->tv2.vec + i);
+-		migrate_timer_list(new_base, old_base->tv3.vec + i);
+-		migrate_timer_list(new_base, old_base->tv4.vec + i);
+-		migrate_timer_list(new_base, old_base->tv5.vec + i);
++		BUG_ON(old_base->running_timer);
++
++		for (i = 0; i < WHEEL_SIZE; i++)
++			migrate_timer_list(new_base, old_base->vectors + i);
++
++		raw_spin_unlock(&old_base->lock);
++		raw_spin_unlock_irq(&new_base->lock);
++		put_cpu_ptr(&timer_bases);
+ 	}
+-
+-	old_base->active_timers = 0;
+-	old_base->all_timers = 0;
+-
+-	spin_unlock(&old_base->lock);
+-	spin_unlock_irq(&new_base->lock);
+-	put_cpu_ptr(&tvec_bases);
+ }
+ 
+ static int timer_cpu_notify(struct notifier_block *self,
+@@ -1652,13 +1908,18 @@ static inline void timer_register_cpu_notifier(void) { }
+ 
+ static void __init init_timer_cpu(int cpu)
+ {
+-	struct tvec_base *base = per_cpu_ptr(&tvec_bases, cpu);
++	struct timer_base *base;
++	int i;
+ 
+-	base->cpu = cpu;
+-	spin_lock_init(&base->lock);
+-
+-	base->timer_jiffies = jiffies;
+-	base->next_timer = base->timer_jiffies;
++	for (i = 0; i < NR_BASES; i++) {
++		base = per_cpu_ptr(&timer_bases[i], cpu);
++		base->cpu = cpu;
++		raw_spin_lock_init(&base->lock);
++		base->clk = jiffies;
++#ifdef CONFIG_PREEMPT_RT_FULL
++		init_swait_queue_head(&base->wait_for_running_timer);
++#endif
++	}
+ }
+ 
+ static void __init init_timer_cpus(void)
+diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
+index e45db6b0d878..364ccd0eb57b 100644
+--- a/kernel/trace/Kconfig
++++ b/kernel/trace/Kconfig
+@@ -187,6 +187,24 @@ config IRQSOFF_TRACER
+ 	  enabled. This option and the preempt-off timing option can be
+ 	  used together or separately.)
+ 
++config INTERRUPT_OFF_HIST
++	bool "Interrupts-off Latency Histogram"
++	depends on IRQSOFF_TRACER
++	help
++	  This option generates continuously updated histograms (one per cpu)
++	  of the duration of time periods with interrupts disabled. The
++	  histograms are disabled by default. To enable them, write a non-zero
++	  number to
++
++	      /sys/kernel/debug/tracing/latency_hist/enable/preemptirqsoff
++
++	  If PREEMPT_OFF_HIST is also selected, additional histograms (one
++	  per cpu) are generated that accumulate the duration of time periods
++	  when both interrupts and preemption are disabled. The histogram data
++	  will be located in the debug file system at
++
++	      /sys/kernel/debug/tracing/latency_hist/irqsoff
++
+ config PREEMPT_TRACER
+ 	bool "Preemption-off Latency Tracer"
+ 	default n
+@@ -211,6 +229,24 @@ config PREEMPT_TRACER
+ 	  enabled. This option and the irqs-off timing option can be
+ 	  used together or separately.)
+ 
++config PREEMPT_OFF_HIST
++	bool "Preemption-off Latency Histogram"
++	depends on PREEMPT_TRACER
++	help
++	  This option generates continuously updated histograms (one per cpu)
++	  of the duration of time periods with preemption disabled. The
++	  histograms are disabled by default. To enable them, write a non-zero
++	  number to
++
++	      /sys/kernel/debug/tracing/latency_hist/enable/preemptirqsoff
++
++	  If INTERRUPT_OFF_HIST is also selected, additional histograms (one
++	  per cpu) are generated that accumulate the duration of time periods
++	  when both interrupts and preemption are disabled. The histogram data
++	  will be located in the debug file system at
++
++	      /sys/kernel/debug/tracing/latency_hist/preemptoff
++
+ config SCHED_TRACER
+ 	bool "Scheduling Latency Tracer"
+ 	select GENERIC_TRACER
+@@ -221,6 +257,74 @@ config SCHED_TRACER
+ 	  This tracer tracks the latency of the highest priority task
+ 	  to be scheduled in, starting from the point it has woken up.
+ 
++config WAKEUP_LATENCY_HIST
++	bool "Scheduling Latency Histogram"
++	depends on SCHED_TRACER
++	help
++	  This option generates continuously updated histograms (one per cpu)
++	  of the scheduling latency of the highest priority task.
++	  The histograms are disabled by default. To enable them, write a
++	  non-zero number to
++
++	      /sys/kernel/debug/tracing/latency_hist/enable/wakeup
++
++	  Two different algorithms are used, one to determine the latency of
++	  processes that exclusively use the highest priority of the system and
++	  another one to determine the latency of processes that share the
++	  highest system priority with other processes. The former is used to
++	  improve hardware and system software, the latter to optimize the
++	  priority design of a given system. The histogram data will be
++	  located in the debug file system at
++
++	      /sys/kernel/debug/tracing/latency_hist/wakeup
++
++	  and
++
++	      /sys/kernel/debug/tracing/latency_hist/wakeup/sharedprio
++
++	  If both Scheduling Latency Histogram and Missed Timer Offsets
++	  Histogram are selected, additional histogram data will be collected
++	  that contain, in addition to the wakeup latency, the timer latency, in
++	  case the wakeup was triggered by an expired timer. These histograms
++	  are available in the
++
++	      /sys/kernel/debug/tracing/latency_hist/timerandwakeup
++
++	  directory. They reflect the apparent interrupt and scheduling latency
++	  and are best suitable to determine the worst-case latency of a given
++	  system. To enable these histograms, write a non-zero number to
++
++	      /sys/kernel/debug/tracing/latency_hist/enable/timerandwakeup
++
++config MISSED_TIMER_OFFSETS_HIST
++	depends on HIGH_RES_TIMERS
++	select GENERIC_TRACER
++	bool "Missed Timer Offsets Histogram"
++	help
++	  Generate a histogram of missed timer offsets in microseconds. The
++	  histograms are disabled by default. To enable them, write a non-zero
++	  number to
++
++	      /sys/kernel/debug/tracing/latency_hist/enable/missed_timer_offsets
++
++	  The histogram data will be located in the debug file system at
++
++	      /sys/kernel/debug/tracing/latency_hist/missed_timer_offsets
++
++	  If both Scheduling Latency Histogram and Missed Timer Offsets
++	  Histogram are selected, additional histogram data will be collected
++	  that contain, in addition to the wakeup latency, the timer latency, in
++	  case the wakeup was triggered by an expired timer. These histograms
++	  are available in the
++
++	      /sys/kernel/debug/tracing/latency_hist/timerandwakeup
++
++	  directory. They reflect the apparent interrupt and scheduling latency
++	  and are best suitable to determine the worst-case latency of a given
++	  system. To enable these histograms, write a non-zero number to
++
++	      /sys/kernel/debug/tracing/latency_hist/enable/timerandwakeup
++
+ config ENABLE_DEFAULT_TRACERS
+ 	bool "Trace process context switches and events"
+ 	depends on !GENERIC_TRACER
+diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
+index 9b1044e936a6..3bbaea06824a 100644
+--- a/kernel/trace/Makefile
++++ b/kernel/trace/Makefile
+@@ -36,6 +36,10 @@ obj-$(CONFIG_FUNCTION_TRACER) += trace_functions.o
+ obj-$(CONFIG_IRQSOFF_TRACER) += trace_irqsoff.o
+ obj-$(CONFIG_PREEMPT_TRACER) += trace_irqsoff.o
+ obj-$(CONFIG_SCHED_TRACER) += trace_sched_wakeup.o
++obj-$(CONFIG_INTERRUPT_OFF_HIST) += latency_hist.o
++obj-$(CONFIG_PREEMPT_OFF_HIST) += latency_hist.o
++obj-$(CONFIG_WAKEUP_LATENCY_HIST) += latency_hist.o
++obj-$(CONFIG_MISSED_TIMER_OFFSETS_HIST) += latency_hist.o
+ obj-$(CONFIG_NOP_TRACER) += trace_nop.o
+ obj-$(CONFIG_STACK_TRACER) += trace_stack.o
+ obj-$(CONFIG_MMIOTRACE) += trace_mmiotrace.o
+diff --git a/kernel/trace/latency_hist.c b/kernel/trace/latency_hist.c
+new file mode 100644
+index 000000000000..7f6ee70dea41
+--- /dev/null
++++ b/kernel/trace/latency_hist.c
+@@ -0,0 +1,1178 @@
++/*
++ * kernel/trace/latency_hist.c
++ *
++ * Add support for histograms of preemption-off latency and
++ * interrupt-off latency and wakeup latency, it depends on
++ * Real-Time Preemption Support.
++ *
++ *  Copyright (C) 2005 MontaVista Software, Inc.
++ *  Yi Yang <yyang@ch.mvista.com>
++ *
++ *  Converted to work with the new latency tracer.
++ *  Copyright (C) 2008 Red Hat, Inc.
++ *    Steven Rostedt <srostedt@redhat.com>
++ *
++ */
++#include <linux/module.h>
++#include <linux/debugfs.h>
++#include <linux/seq_file.h>
++#include <linux/percpu.h>
++#include <linux/kallsyms.h>
++#include <linux/uaccess.h>
++#include <linux/sched.h>
++#include <linux/sched/rt.h>
++#include <linux/slab.h>
++#include <linux/atomic.h>
++#include <asm/div64.h>
++
++#include "trace.h"
++#include <trace/events/sched.h>
++
++#define NSECS_PER_USECS 1000L
++
++#define CREATE_TRACE_POINTS
++#include <trace/events/hist.h>
++
++enum {
++	IRQSOFF_LATENCY = 0,
++	PREEMPTOFF_LATENCY,
++	PREEMPTIRQSOFF_LATENCY,
++	WAKEUP_LATENCY,
++	WAKEUP_LATENCY_SHAREDPRIO,
++	MISSED_TIMER_OFFSETS,
++	TIMERANDWAKEUP_LATENCY,
++	MAX_LATENCY_TYPE,
++};
++
++#define MAX_ENTRY_NUM 10240
++
++struct hist_data {
++	atomic_t hist_mode; /* 0 log, 1 don't log */
++	long offset; /* set it to MAX_ENTRY_NUM/2 for a bipolar scale */
++	long min_lat;
++	long max_lat;
++	unsigned long long below_hist_bound_samples;
++	unsigned long long above_hist_bound_samples;
++	long long accumulate_lat;
++	unsigned long long total_samples;
++	unsigned long long hist_array[MAX_ENTRY_NUM];
++};
++
++struct enable_data {
++	int latency_type;
++	int enabled;
++};
++
++static char *latency_hist_dir_root = "latency_hist";
++
++#ifdef CONFIG_INTERRUPT_OFF_HIST
++static DEFINE_PER_CPU(struct hist_data, irqsoff_hist);
++static char *irqsoff_hist_dir = "irqsoff";
++static DEFINE_PER_CPU(cycles_t, hist_irqsoff_start);
++static DEFINE_PER_CPU(int, hist_irqsoff_counting);
++#endif
++
++#ifdef CONFIG_PREEMPT_OFF_HIST
++static DEFINE_PER_CPU(struct hist_data, preemptoff_hist);
++static char *preemptoff_hist_dir = "preemptoff";
++static DEFINE_PER_CPU(cycles_t, hist_preemptoff_start);
++static DEFINE_PER_CPU(int, hist_preemptoff_counting);
++#endif
++
++#if defined(CONFIG_PREEMPT_OFF_HIST) && defined(CONFIG_INTERRUPT_OFF_HIST)
++static DEFINE_PER_CPU(struct hist_data, preemptirqsoff_hist);
++static char *preemptirqsoff_hist_dir = "preemptirqsoff";
++static DEFINE_PER_CPU(cycles_t, hist_preemptirqsoff_start);
++static DEFINE_PER_CPU(int, hist_preemptirqsoff_counting);
++#endif
++
++#if defined(CONFIG_PREEMPT_OFF_HIST) || defined(CONFIG_INTERRUPT_OFF_HIST)
++static notrace void probe_preemptirqsoff_hist(void *v, int reason, int start);
++static struct enable_data preemptirqsoff_enabled_data = {
++	.latency_type = PREEMPTIRQSOFF_LATENCY,
++	.enabled = 0,
++};
++#endif
++
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
++	defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++struct maxlatproc_data {
++	char comm[FIELD_SIZEOF(struct task_struct, comm)];
++	char current_comm[FIELD_SIZEOF(struct task_struct, comm)];
++	int pid;
++	int current_pid;
++	int prio;
++	int current_prio;
++	long latency;
++	long timeroffset;
++	cycle_t timestamp;
++};
++#endif
++
++#ifdef CONFIG_WAKEUP_LATENCY_HIST
++static DEFINE_PER_CPU(struct hist_data, wakeup_latency_hist);
++static DEFINE_PER_CPU(struct hist_data, wakeup_latency_hist_sharedprio);
++static char *wakeup_latency_hist_dir = "wakeup";
++static char *wakeup_latency_hist_dir_sharedprio = "sharedprio";
++static notrace void probe_wakeup_latency_hist_start(void *v,
++	struct task_struct *p);
++static notrace void probe_wakeup_latency_hist_stop(void *v,
++	bool preempt, struct task_struct *prev, struct task_struct *next);
++static notrace void probe_sched_migrate_task(void *,
++	struct task_struct *task, int cpu);
++static struct enable_data wakeup_latency_enabled_data = {
++	.latency_type = WAKEUP_LATENCY,
++	.enabled = 0,
++};
++static DEFINE_PER_CPU(struct maxlatproc_data, wakeup_maxlatproc);
++static DEFINE_PER_CPU(struct maxlatproc_data, wakeup_maxlatproc_sharedprio);
++static DEFINE_PER_CPU(struct task_struct *, wakeup_task);
++static DEFINE_PER_CPU(int, wakeup_sharedprio);
++static unsigned long wakeup_pid;
++#endif
++
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++static DEFINE_PER_CPU(struct hist_data, missed_timer_offsets);
++static char *missed_timer_offsets_dir = "missed_timer_offsets";
++static notrace void probe_hrtimer_interrupt(void *v, int cpu,
++	long long offset, struct task_struct *curr, struct task_struct *task);
++static struct enable_data missed_timer_offsets_enabled_data = {
++	.latency_type = MISSED_TIMER_OFFSETS,
++	.enabled = 0,
++};
++static DEFINE_PER_CPU(struct maxlatproc_data, missed_timer_offsets_maxlatproc);
++static unsigned long missed_timer_offsets_pid;
++#endif
++
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) && \
++	defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++static DEFINE_PER_CPU(struct hist_data, timerandwakeup_latency_hist);
++static char *timerandwakeup_latency_hist_dir = "timerandwakeup";
++static struct enable_data timerandwakeup_enabled_data = {
++	.latency_type = TIMERANDWAKEUP_LATENCY,
++	.enabled = 0,
++};
++static DEFINE_PER_CPU(struct maxlatproc_data, timerandwakeup_maxlatproc);
++#endif
++
++void notrace latency_hist(int latency_type, int cpu, long latency,
++			  long timeroffset, cycle_t stop,
++			  struct task_struct *p)
++{
++	struct hist_data *my_hist;
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
++	defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++	struct maxlatproc_data *mp = NULL;
++#endif
++
++	if (!cpu_possible(cpu) || latency_type < 0 ||
++	    latency_type >= MAX_LATENCY_TYPE)
++		return;
++
++	switch (latency_type) {
++#ifdef CONFIG_INTERRUPT_OFF_HIST
++	case IRQSOFF_LATENCY:
++		my_hist = &per_cpu(irqsoff_hist, cpu);
++		break;
++#endif
++#ifdef CONFIG_PREEMPT_OFF_HIST
++	case PREEMPTOFF_LATENCY:
++		my_hist = &per_cpu(preemptoff_hist, cpu);
++		break;
++#endif
++#if defined(CONFIG_PREEMPT_OFF_HIST) && defined(CONFIG_INTERRUPT_OFF_HIST)
++	case PREEMPTIRQSOFF_LATENCY:
++		my_hist = &per_cpu(preemptirqsoff_hist, cpu);
++		break;
++#endif
++#ifdef CONFIG_WAKEUP_LATENCY_HIST
++	case WAKEUP_LATENCY:
++		my_hist = &per_cpu(wakeup_latency_hist, cpu);
++		mp = &per_cpu(wakeup_maxlatproc, cpu);
++		break;
++	case WAKEUP_LATENCY_SHAREDPRIO:
++		my_hist = &per_cpu(wakeup_latency_hist_sharedprio, cpu);
++		mp = &per_cpu(wakeup_maxlatproc_sharedprio, cpu);
++		break;
++#endif
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++	case MISSED_TIMER_OFFSETS:
++		my_hist = &per_cpu(missed_timer_offsets, cpu);
++		mp = &per_cpu(missed_timer_offsets_maxlatproc, cpu);
++		break;
++#endif
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) && \
++	defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++	case TIMERANDWAKEUP_LATENCY:
++		my_hist = &per_cpu(timerandwakeup_latency_hist, cpu);
++		mp = &per_cpu(timerandwakeup_maxlatproc, cpu);
++		break;
++#endif
++
++	default:
++		return;
++	}
++
++	latency += my_hist->offset;
++
++	if (atomic_read(&my_hist->hist_mode) == 0)
++		return;
++
++	if (latency < 0 || latency >= MAX_ENTRY_NUM) {
++		if (latency < 0)
++			my_hist->below_hist_bound_samples++;
++		else
++			my_hist->above_hist_bound_samples++;
++	} else
++		my_hist->hist_array[latency]++;
++
++	if (unlikely(latency > my_hist->max_lat ||
++	    my_hist->min_lat == LONG_MAX)) {
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
++	defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++		if (latency_type == WAKEUP_LATENCY ||
++		    latency_type == WAKEUP_LATENCY_SHAREDPRIO ||
++		    latency_type == MISSED_TIMER_OFFSETS ||
++		    latency_type == TIMERANDWAKEUP_LATENCY) {
++			strncpy(mp->comm, p->comm, sizeof(mp->comm));
++			strncpy(mp->current_comm, current->comm,
++			    sizeof(mp->current_comm));
++			mp->pid = task_pid_nr(p);
++			mp->current_pid = task_pid_nr(current);
++			mp->prio = p->prio;
++			mp->current_prio = current->prio;
++			mp->latency = latency;
++			mp->timeroffset = timeroffset;
++			mp->timestamp = stop;
++		}
++#endif
++		my_hist->max_lat = latency;
++	}
++	if (unlikely(latency < my_hist->min_lat))
++		my_hist->min_lat = latency;
++	my_hist->total_samples++;
++	my_hist->accumulate_lat += latency;
++}
++
++static void *l_start(struct seq_file *m, loff_t *pos)
++{
++	loff_t *index_ptr = NULL;
++	loff_t index = *pos;
++	struct hist_data *my_hist = m->private;
++
++	if (index == 0) {
++		char minstr[32], avgstr[32], maxstr[32];
++
++		atomic_dec(&my_hist->hist_mode);
++
++		if (likely(my_hist->total_samples)) {
++			long avg = (long) div64_s64(my_hist->accumulate_lat,
++			    my_hist->total_samples);
++			snprintf(minstr, sizeof(minstr), "%ld",
++			    my_hist->min_lat - my_hist->offset);
++			snprintf(avgstr, sizeof(avgstr), "%ld",
++			    avg - my_hist->offset);
++			snprintf(maxstr, sizeof(maxstr), "%ld",
++			    my_hist->max_lat - my_hist->offset);
++		} else {
++			strcpy(minstr, "<undef>");
++			strcpy(avgstr, minstr);
++			strcpy(maxstr, minstr);
++		}
++
++		seq_printf(m, "#Minimum latency: %s microseconds\n"
++			   "#Average latency: %s microseconds\n"
++			   "#Maximum latency: %s microseconds\n"
++			   "#Total samples: %llu\n"
++			   "#There are %llu samples lower than %ld"
++			   " microseconds.\n"
++			   "#There are %llu samples greater or equal"
++			   " than %ld microseconds.\n"
++			   "#usecs\t%16s\n",
++			   minstr, avgstr, maxstr,
++			   my_hist->total_samples,
++			   my_hist->below_hist_bound_samples,
++			   -my_hist->offset,
++			   my_hist->above_hist_bound_samples,
++			   MAX_ENTRY_NUM - my_hist->offset,
++			   "samples");
++	}
++	if (index < MAX_ENTRY_NUM) {
++		index_ptr = kmalloc(sizeof(loff_t), GFP_KERNEL);
++		if (index_ptr)
++			*index_ptr = index;
++	}
++
++	return index_ptr;
++}
++
++static void *l_next(struct seq_file *m, void *p, loff_t *pos)
++{
++	loff_t *index_ptr = p;
++	struct hist_data *my_hist = m->private;
++
++	if (++*pos >= MAX_ENTRY_NUM) {
++		atomic_inc(&my_hist->hist_mode);
++		return NULL;
++	}
++	*index_ptr = *pos;
++	return index_ptr;
++}
++
++static void l_stop(struct seq_file *m, void *p)
++{
++	kfree(p);
++}
++
++static int l_show(struct seq_file *m, void *p)
++{
++	int index = *(loff_t *) p;
++	struct hist_data *my_hist = m->private;
++
++	seq_printf(m, "%6ld\t%16llu\n", index - my_hist->offset,
++	    my_hist->hist_array[index]);
++	return 0;
++}
++
++static const struct seq_operations latency_hist_seq_op = {
++	.start = l_start,
++	.next  = l_next,
++	.stop  = l_stop,
++	.show  = l_show
++};
++
++static int latency_hist_open(struct inode *inode, struct file *file)
++{
++	int ret;
++
++	ret = seq_open(file, &latency_hist_seq_op);
++	if (!ret) {
++		struct seq_file *seq = file->private_data;
++		seq->private = inode->i_private;
++	}
++	return ret;
++}
++
++static const struct file_operations latency_hist_fops = {
++	.open = latency_hist_open,
++	.read = seq_read,
++	.llseek = seq_lseek,
++	.release = seq_release,
++};
++
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
++	defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++static void clear_maxlatprocdata(struct maxlatproc_data *mp)
++{
++	mp->comm[0] = mp->current_comm[0] = '\0';
++	mp->prio = mp->current_prio = mp->pid = mp->current_pid =
++	    mp->latency = mp->timeroffset = -1;
++	mp->timestamp = 0;
++}
++#endif
++
++static void hist_reset(struct hist_data *hist)
++{
++	atomic_dec(&hist->hist_mode);
++
++	memset(hist->hist_array, 0, sizeof(hist->hist_array));
++	hist->below_hist_bound_samples = 0ULL;
++	hist->above_hist_bound_samples = 0ULL;
++	hist->min_lat = LONG_MAX;
++	hist->max_lat = LONG_MIN;
++	hist->total_samples = 0ULL;
++	hist->accumulate_lat = 0LL;
++
++	atomic_inc(&hist->hist_mode);
++}
++
++static ssize_t
++latency_hist_reset(struct file *file, const char __user *a,
++		   size_t size, loff_t *off)
++{
++	int cpu;
++	struct hist_data *hist = NULL;
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
++	defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++	struct maxlatproc_data *mp = NULL;
++#endif
++	off_t latency_type = (off_t) file->private_data;
++
++	for_each_online_cpu(cpu) {
++
++		switch (latency_type) {
++#ifdef CONFIG_PREEMPT_OFF_HIST
++		case PREEMPTOFF_LATENCY:
++			hist = &per_cpu(preemptoff_hist, cpu);
++			break;
++#endif
++#ifdef CONFIG_INTERRUPT_OFF_HIST
++		case IRQSOFF_LATENCY:
++			hist = &per_cpu(irqsoff_hist, cpu);
++			break;
++#endif
++#if defined(CONFIG_INTERRUPT_OFF_HIST) && defined(CONFIG_PREEMPT_OFF_HIST)
++		case PREEMPTIRQSOFF_LATENCY:
++			hist = &per_cpu(preemptirqsoff_hist, cpu);
++			break;
++#endif
++#ifdef CONFIG_WAKEUP_LATENCY_HIST
++		case WAKEUP_LATENCY:
++			hist = &per_cpu(wakeup_latency_hist, cpu);
++			mp = &per_cpu(wakeup_maxlatproc, cpu);
++			break;
++		case WAKEUP_LATENCY_SHAREDPRIO:
++			hist = &per_cpu(wakeup_latency_hist_sharedprio, cpu);
++			mp = &per_cpu(wakeup_maxlatproc_sharedprio, cpu);
++			break;
++#endif
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++		case MISSED_TIMER_OFFSETS:
++			hist = &per_cpu(missed_timer_offsets, cpu);
++			mp = &per_cpu(missed_timer_offsets_maxlatproc, cpu);
++			break;
++#endif
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) && \
++	defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++		case TIMERANDWAKEUP_LATENCY:
++			hist = &per_cpu(timerandwakeup_latency_hist, cpu);
++			mp = &per_cpu(timerandwakeup_maxlatproc, cpu);
++			break;
++#endif
++		}
++
++		hist_reset(hist);
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
++	defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++		if (latency_type == WAKEUP_LATENCY ||
++		    latency_type == WAKEUP_LATENCY_SHAREDPRIO ||
++		    latency_type == MISSED_TIMER_OFFSETS ||
++		    latency_type == TIMERANDWAKEUP_LATENCY)
++			clear_maxlatprocdata(mp);
++#endif
++	}
++
++	return size;
++}
++
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
++	defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++static ssize_t
++show_pid(struct file *file, char __user *ubuf, size_t cnt, loff_t *ppos)
++{
++	char buf[64];
++	int r;
++	unsigned long *this_pid = file->private_data;
++
++	r = snprintf(buf, sizeof(buf), "%lu\n", *this_pid);
++	return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
++}
++
++static ssize_t do_pid(struct file *file, const char __user *ubuf,
++		      size_t cnt, loff_t *ppos)
++{
++	char buf[64];
++	unsigned long pid;
++	unsigned long *this_pid = file->private_data;
++
++	if (cnt >= sizeof(buf))
++		return -EINVAL;
++
++	if (copy_from_user(&buf, ubuf, cnt))
++		return -EFAULT;
++
++	buf[cnt] = '\0';
++
++	if (kstrtoul(buf, 10, &pid))
++		return -EINVAL;
++
++	*this_pid = pid;
++
++	return cnt;
++}
++#endif
++
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
++	defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++static ssize_t
++show_maxlatproc(struct file *file, char __user *ubuf, size_t cnt, loff_t *ppos)
++{
++	int r;
++	struct maxlatproc_data *mp = file->private_data;
++	int strmaxlen = (TASK_COMM_LEN * 2) + (8 * 8);
++	unsigned long long t;
++	unsigned long usecs, secs;
++	char *buf;
++
++	if (mp->pid == -1 || mp->current_pid == -1) {
++		buf = "(none)\n";
++		return simple_read_from_buffer(ubuf, cnt, ppos, buf,
++		    strlen(buf));
++	}
++
++	buf = kmalloc(strmaxlen, GFP_KERNEL);
++	if (buf == NULL)
++		return -ENOMEM;
++
++	t = ns2usecs(mp->timestamp);
++	usecs = do_div(t, USEC_PER_SEC);
++	secs = (unsigned long) t;
++	r = snprintf(buf, strmaxlen,
++	    "%d %d %ld (%ld) %s <- %d %d %s %lu.%06lu\n", mp->pid,
++	    MAX_RT_PRIO-1 - mp->prio, mp->latency, mp->timeroffset, mp->comm,
++	    mp->current_pid, MAX_RT_PRIO-1 - mp->current_prio, mp->current_comm,
++	    secs, usecs);
++	r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
++	kfree(buf);
++	return r;
++}
++#endif
++
++static ssize_t
++show_enable(struct file *file, char __user *ubuf, size_t cnt, loff_t *ppos)
++{
++	char buf[64];
++	struct enable_data *ed = file->private_data;
++	int r;
++
++	r = snprintf(buf, sizeof(buf), "%d\n", ed->enabled);
++	return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
++}
++
++static ssize_t
++do_enable(struct file *file, const char __user *ubuf, size_t cnt, loff_t *ppos)
++{
++	char buf[64];
++	long enable;
++	struct enable_data *ed = file->private_data;
++
++	if (cnt >= sizeof(buf))
++		return -EINVAL;
++
++	if (copy_from_user(&buf, ubuf, cnt))
++		return -EFAULT;
++
++	buf[cnt] = 0;
++
++	if (kstrtoul(buf, 10, &enable))
++		return -EINVAL;
++
++	if ((enable && ed->enabled) || (!enable && !ed->enabled))
++		return cnt;
++
++	if (enable) {
++		int ret;
++
++		switch (ed->latency_type) {
++#if defined(CONFIG_INTERRUPT_OFF_HIST) || defined(CONFIG_PREEMPT_OFF_HIST)
++		case PREEMPTIRQSOFF_LATENCY:
++			ret = register_trace_preemptirqsoff_hist(
++			    probe_preemptirqsoff_hist, NULL);
++			if (ret) {
++				pr_info("wakeup trace: Couldn't assign "
++				    "probe_preemptirqsoff_hist "
++				    "to trace_preemptirqsoff_hist\n");
++				return ret;
++			}
++			break;
++#endif
++#ifdef CONFIG_WAKEUP_LATENCY_HIST
++		case WAKEUP_LATENCY:
++			ret = register_trace_sched_wakeup(
++			    probe_wakeup_latency_hist_start, NULL);
++			if (ret) {
++				pr_info("wakeup trace: Couldn't assign "
++				    "probe_wakeup_latency_hist_start "
++				    "to trace_sched_wakeup\n");
++				return ret;
++			}
++			ret = register_trace_sched_wakeup_new(
++			    probe_wakeup_latency_hist_start, NULL);
++			if (ret) {
++				pr_info("wakeup trace: Couldn't assign "
++				    "probe_wakeup_latency_hist_start "
++				    "to trace_sched_wakeup_new\n");
++				unregister_trace_sched_wakeup(
++				    probe_wakeup_latency_hist_start, NULL);
++				return ret;
++			}
++			ret = register_trace_sched_switch(
++			    probe_wakeup_latency_hist_stop, NULL);
++			if (ret) {
++				pr_info("wakeup trace: Couldn't assign "
++				    "probe_wakeup_latency_hist_stop "
++				    "to trace_sched_switch\n");
++				unregister_trace_sched_wakeup(
++				    probe_wakeup_latency_hist_start, NULL);
++				unregister_trace_sched_wakeup_new(
++				    probe_wakeup_latency_hist_start, NULL);
++				return ret;
++			}
++			ret = register_trace_sched_migrate_task(
++			    probe_sched_migrate_task, NULL);
++			if (ret) {
++				pr_info("wakeup trace: Couldn't assign "
++				    "probe_sched_migrate_task "
++				    "to trace_sched_migrate_task\n");
++				unregister_trace_sched_wakeup(
++				    probe_wakeup_latency_hist_start, NULL);
++				unregister_trace_sched_wakeup_new(
++				    probe_wakeup_latency_hist_start, NULL);
++				unregister_trace_sched_switch(
++				    probe_wakeup_latency_hist_stop, NULL);
++				return ret;
++			}
++			break;
++#endif
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++		case MISSED_TIMER_OFFSETS:
++			ret = register_trace_hrtimer_interrupt(
++			    probe_hrtimer_interrupt, NULL);
++			if (ret) {
++				pr_info("wakeup trace: Couldn't assign "
++				    "probe_hrtimer_interrupt "
++				    "to trace_hrtimer_interrupt\n");
++				return ret;
++			}
++			break;
++#endif
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) && \
++	defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++		case TIMERANDWAKEUP_LATENCY:
++			if (!wakeup_latency_enabled_data.enabled ||
++			    !missed_timer_offsets_enabled_data.enabled)
++				return -EINVAL;
++			break;
++#endif
++		default:
++			break;
++		}
++	} else {
++		switch (ed->latency_type) {
++#if defined(CONFIG_INTERRUPT_OFF_HIST) || defined(CONFIG_PREEMPT_OFF_HIST)
++		case PREEMPTIRQSOFF_LATENCY:
++			{
++				int cpu;
++
++				unregister_trace_preemptirqsoff_hist(
++				    probe_preemptirqsoff_hist, NULL);
++				for_each_online_cpu(cpu) {
++#ifdef CONFIG_INTERRUPT_OFF_HIST
++					per_cpu(hist_irqsoff_counting,
++					    cpu) = 0;
++#endif
++#ifdef CONFIG_PREEMPT_OFF_HIST
++					per_cpu(hist_preemptoff_counting,
++					    cpu) = 0;
++#endif
++#if defined(CONFIG_INTERRUPT_OFF_HIST) && defined(CONFIG_PREEMPT_OFF_HIST)
++					per_cpu(hist_preemptirqsoff_counting,
++					    cpu) = 0;
++#endif
++				}
++			}
++			break;
++#endif
++#ifdef CONFIG_WAKEUP_LATENCY_HIST
++		case WAKEUP_LATENCY:
++			{
++				int cpu;
++
++				unregister_trace_sched_wakeup(
++				    probe_wakeup_latency_hist_start, NULL);
++				unregister_trace_sched_wakeup_new(
++				    probe_wakeup_latency_hist_start, NULL);
++				unregister_trace_sched_switch(
++				    probe_wakeup_latency_hist_stop, NULL);
++				unregister_trace_sched_migrate_task(
++				    probe_sched_migrate_task, NULL);
++
++				for_each_online_cpu(cpu) {
++					per_cpu(wakeup_task, cpu) = NULL;
++					per_cpu(wakeup_sharedprio, cpu) = 0;
++				}
++			}
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++			timerandwakeup_enabled_data.enabled = 0;
++#endif
++			break;
++#endif
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++		case MISSED_TIMER_OFFSETS:
++			unregister_trace_hrtimer_interrupt(
++			    probe_hrtimer_interrupt, NULL);
++#ifdef CONFIG_WAKEUP_LATENCY_HIST
++			timerandwakeup_enabled_data.enabled = 0;
++#endif
++			break;
++#endif
++		default:
++			break;
++		}
++	}
++	ed->enabled = enable;
++	return cnt;
++}
++
++static const struct file_operations latency_hist_reset_fops = {
++	.open = tracing_open_generic,
++	.write = latency_hist_reset,
++};
++
++static const struct file_operations enable_fops = {
++	.open = tracing_open_generic,
++	.read = show_enable,
++	.write = do_enable,
++};
++
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
++	defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++static const struct file_operations pid_fops = {
++	.open = tracing_open_generic,
++	.read = show_pid,
++	.write = do_pid,
++};
++
++static const struct file_operations maxlatproc_fops = {
++	.open = tracing_open_generic,
++	.read = show_maxlatproc,
++};
++#endif
++
++#if defined(CONFIG_INTERRUPT_OFF_HIST) || defined(CONFIG_PREEMPT_OFF_HIST)
++static notrace void probe_preemptirqsoff_hist(void *v, int reason,
++	int starthist)
++{
++	int cpu = raw_smp_processor_id();
++	int time_set = 0;
++
++	if (starthist) {
++		cycle_t uninitialized_var(start);
++
++		if (!preempt_count() && !irqs_disabled())
++			return;
++
++#ifdef CONFIG_INTERRUPT_OFF_HIST
++		if ((reason == IRQS_OFF || reason == TRACE_START) &&
++		    !per_cpu(hist_irqsoff_counting, cpu)) {
++			per_cpu(hist_irqsoff_counting, cpu) = 1;
++			start = ftrace_now(cpu);
++			time_set++;
++			per_cpu(hist_irqsoff_start, cpu) = start;
++		}
++#endif
++
++#ifdef CONFIG_PREEMPT_OFF_HIST
++		if ((reason == PREEMPT_OFF || reason == TRACE_START) &&
++		    !per_cpu(hist_preemptoff_counting, cpu)) {
++			per_cpu(hist_preemptoff_counting, cpu) = 1;
++			if (!(time_set++))
++				start = ftrace_now(cpu);
++			per_cpu(hist_preemptoff_start, cpu) = start;
++		}
++#endif
++
++#if defined(CONFIG_INTERRUPT_OFF_HIST) && defined(CONFIG_PREEMPT_OFF_HIST)
++		if (per_cpu(hist_irqsoff_counting, cpu) &&
++		    per_cpu(hist_preemptoff_counting, cpu) &&
++		    !per_cpu(hist_preemptirqsoff_counting, cpu)) {
++			per_cpu(hist_preemptirqsoff_counting, cpu) = 1;
++			if (!time_set)
++				start = ftrace_now(cpu);
++			per_cpu(hist_preemptirqsoff_start, cpu) = start;
++		}
++#endif
++	} else {
++		cycle_t uninitialized_var(stop);
++
++#ifdef CONFIG_INTERRUPT_OFF_HIST
++		if ((reason == IRQS_ON || reason == TRACE_STOP) &&
++		    per_cpu(hist_irqsoff_counting, cpu)) {
++			cycle_t start = per_cpu(hist_irqsoff_start, cpu);
++
++			stop = ftrace_now(cpu);
++			time_set++;
++			if (start) {
++				long latency = ((long) (stop - start)) /
++				    NSECS_PER_USECS;
++
++				latency_hist(IRQSOFF_LATENCY, cpu, latency, 0,
++				    stop, NULL);
++			}
++			per_cpu(hist_irqsoff_counting, cpu) = 0;
++		}
++#endif
++
++#ifdef CONFIG_PREEMPT_OFF_HIST
++		if ((reason == PREEMPT_ON || reason == TRACE_STOP) &&
++		    per_cpu(hist_preemptoff_counting, cpu)) {
++			cycle_t start = per_cpu(hist_preemptoff_start, cpu);
++
++			if (!(time_set++))
++				stop = ftrace_now(cpu);
++			if (start) {
++				long latency = ((long) (stop - start)) /
++				    NSECS_PER_USECS;
++
++				latency_hist(PREEMPTOFF_LATENCY, cpu, latency,
++				    0, stop, NULL);
++			}
++			per_cpu(hist_preemptoff_counting, cpu) = 0;
++		}
++#endif
++
++#if defined(CONFIG_INTERRUPT_OFF_HIST) && defined(CONFIG_PREEMPT_OFF_HIST)
++		if ((!per_cpu(hist_irqsoff_counting, cpu) ||
++		     !per_cpu(hist_preemptoff_counting, cpu)) &&
++		   per_cpu(hist_preemptirqsoff_counting, cpu)) {
++			cycle_t start = per_cpu(hist_preemptirqsoff_start, cpu);
++
++			if (!time_set)
++				stop = ftrace_now(cpu);
++			if (start) {
++				long latency = ((long) (stop - start)) /
++				    NSECS_PER_USECS;
++
++				latency_hist(PREEMPTIRQSOFF_LATENCY, cpu,
++				    latency, 0, stop, NULL);
++			}
++			per_cpu(hist_preemptirqsoff_counting, cpu) = 0;
++		}
++#endif
++	}
++}
++#endif
++
++#ifdef CONFIG_WAKEUP_LATENCY_HIST
++static DEFINE_RAW_SPINLOCK(wakeup_lock);
++static notrace void probe_sched_migrate_task(void *v, struct task_struct *task,
++	int cpu)
++{
++	int old_cpu = task_cpu(task);
++
++	if (cpu != old_cpu) {
++		unsigned long flags;
++		struct task_struct *cpu_wakeup_task;
++
++		raw_spin_lock_irqsave(&wakeup_lock, flags);
++
++		cpu_wakeup_task = per_cpu(wakeup_task, old_cpu);
++		if (task == cpu_wakeup_task) {
++			put_task_struct(cpu_wakeup_task);
++			per_cpu(wakeup_task, old_cpu) = NULL;
++			cpu_wakeup_task = per_cpu(wakeup_task, cpu) = task;
++			get_task_struct(cpu_wakeup_task);
++		}
++
++		raw_spin_unlock_irqrestore(&wakeup_lock, flags);
++	}
++}
++
++static notrace void probe_wakeup_latency_hist_start(void *v,
++	struct task_struct *p)
++{
++	unsigned long flags;
++	struct task_struct *curr = current;
++	int cpu = task_cpu(p);
++	struct task_struct *cpu_wakeup_task;
++
++	raw_spin_lock_irqsave(&wakeup_lock, flags);
++
++	cpu_wakeup_task = per_cpu(wakeup_task, cpu);
++
++	if (wakeup_pid) {
++		if ((cpu_wakeup_task && p->prio == cpu_wakeup_task->prio) ||
++		    p->prio == curr->prio)
++			per_cpu(wakeup_sharedprio, cpu) = 1;
++		if (likely(wakeup_pid != task_pid_nr(p)))
++			goto out;
++	} else {
++		if (likely(!rt_task(p)) ||
++		    (cpu_wakeup_task && p->prio > cpu_wakeup_task->prio) ||
++		    p->prio > curr->prio)
++			goto out;
++		if ((cpu_wakeup_task && p->prio == cpu_wakeup_task->prio) ||
++		    p->prio == curr->prio)
++			per_cpu(wakeup_sharedprio, cpu) = 1;
++	}
++
++	if (cpu_wakeup_task)
++		put_task_struct(cpu_wakeup_task);
++	cpu_wakeup_task = per_cpu(wakeup_task, cpu) = p;
++	get_task_struct(cpu_wakeup_task);
++	cpu_wakeup_task->preempt_timestamp_hist =
++		ftrace_now(raw_smp_processor_id());
++out:
++	raw_spin_unlock_irqrestore(&wakeup_lock, flags);
++}
++
++static notrace void probe_wakeup_latency_hist_stop(void *v,
++	bool preempt, struct task_struct *prev, struct task_struct *next)
++{
++	unsigned long flags;
++	int cpu = task_cpu(next);
++	long latency;
++	cycle_t stop;
++	struct task_struct *cpu_wakeup_task;
++
++	raw_spin_lock_irqsave(&wakeup_lock, flags);
++
++	cpu_wakeup_task = per_cpu(wakeup_task, cpu);
++
++	if (cpu_wakeup_task == NULL)
++		goto out;
++
++	/* Already running? */
++	if (unlikely(current == cpu_wakeup_task))
++		goto out_reset;
++
++	if (next != cpu_wakeup_task) {
++		if (next->prio < cpu_wakeup_task->prio)
++			goto out_reset;
++
++		if (next->prio == cpu_wakeup_task->prio)
++			per_cpu(wakeup_sharedprio, cpu) = 1;
++
++		goto out;
++	}
++
++	if (current->prio == cpu_wakeup_task->prio)
++		per_cpu(wakeup_sharedprio, cpu) = 1;
++
++	/*
++	 * The task we are waiting for is about to be switched to.
++	 * Calculate latency and store it in histogram.
++	 */
++	stop = ftrace_now(raw_smp_processor_id());
++
++	latency = ((long) (stop - next->preempt_timestamp_hist)) /
++	    NSECS_PER_USECS;
++
++	if (per_cpu(wakeup_sharedprio, cpu)) {
++		latency_hist(WAKEUP_LATENCY_SHAREDPRIO, cpu, latency, 0, stop,
++		    next);
++		per_cpu(wakeup_sharedprio, cpu) = 0;
++	} else {
++		latency_hist(WAKEUP_LATENCY, cpu, latency, 0, stop, next);
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++		if (timerandwakeup_enabled_data.enabled) {
++			latency_hist(TIMERANDWAKEUP_LATENCY, cpu,
++			    next->timer_offset + latency, next->timer_offset,
++			    stop, next);
++		}
++#endif
++	}
++
++out_reset:
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++	next->timer_offset = 0;
++#endif
++	put_task_struct(cpu_wakeup_task);
++	per_cpu(wakeup_task, cpu) = NULL;
++out:
++	raw_spin_unlock_irqrestore(&wakeup_lock, flags);
++}
++#endif
++
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++static notrace void probe_hrtimer_interrupt(void *v, int cpu,
++	long long latency_ns, struct task_struct *curr,
++	struct task_struct *task)
++{
++	if (latency_ns <= 0 && task != NULL && rt_task(task) &&
++	    (task->prio < curr->prio ||
++	    (task->prio == curr->prio &&
++	    !cpumask_test_cpu(cpu, &task->cpus_allowed)))) {
++		long latency;
++		cycle_t now;
++
++		if (missed_timer_offsets_pid) {
++			if (likely(missed_timer_offsets_pid !=
++			    task_pid_nr(task)))
++				return;
++		}
++
++		now = ftrace_now(cpu);
++		latency = (long) div_s64(-latency_ns, NSECS_PER_USECS);
++		latency_hist(MISSED_TIMER_OFFSETS, cpu, latency, latency, now,
++		    task);
++#ifdef CONFIG_WAKEUP_LATENCY_HIST
++		task->timer_offset = latency;
++#endif
++	}
++}
++#endif
++
++static __init int latency_hist_init(void)
++{
++	struct dentry *latency_hist_root = NULL;
++	struct dentry *dentry;
++#ifdef CONFIG_WAKEUP_LATENCY_HIST
++	struct dentry *dentry_sharedprio;
++#endif
++	struct dentry *entry;
++	struct dentry *enable_root;
++	int i = 0;
++	struct hist_data *my_hist;
++	char name[64];
++	char *cpufmt = "CPU%d";
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
++	defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++	char *cpufmt_maxlatproc = "max_latency-CPU%d";
++	struct maxlatproc_data *mp = NULL;
++#endif
++
++	dentry = tracing_init_dentry();
++	latency_hist_root = debugfs_create_dir(latency_hist_dir_root, dentry);
++	enable_root = debugfs_create_dir("enable", latency_hist_root);
++
++#ifdef CONFIG_INTERRUPT_OFF_HIST
++	dentry = debugfs_create_dir(irqsoff_hist_dir, latency_hist_root);
++	for_each_possible_cpu(i) {
++		sprintf(name, cpufmt, i);
++		entry = debugfs_create_file(name, 0444, dentry,
++		    &per_cpu(irqsoff_hist, i), &latency_hist_fops);
++		my_hist = &per_cpu(irqsoff_hist, i);
++		atomic_set(&my_hist->hist_mode, 1);
++		my_hist->min_lat = LONG_MAX;
++	}
++	entry = debugfs_create_file("reset", 0644, dentry,
++	    (void *)IRQSOFF_LATENCY, &latency_hist_reset_fops);
++#endif
++
++#ifdef CONFIG_PREEMPT_OFF_HIST
++	dentry = debugfs_create_dir(preemptoff_hist_dir,
++	    latency_hist_root);
++	for_each_possible_cpu(i) {
++		sprintf(name, cpufmt, i);
++		entry = debugfs_create_file(name, 0444, dentry,
++		    &per_cpu(preemptoff_hist, i), &latency_hist_fops);
++		my_hist = &per_cpu(preemptoff_hist, i);
++		atomic_set(&my_hist->hist_mode, 1);
++		my_hist->min_lat = LONG_MAX;
++	}
++	entry = debugfs_create_file("reset", 0644, dentry,
++	    (void *)PREEMPTOFF_LATENCY, &latency_hist_reset_fops);
++#endif
++
++#if defined(CONFIG_INTERRUPT_OFF_HIST) && defined(CONFIG_PREEMPT_OFF_HIST)
++	dentry = debugfs_create_dir(preemptirqsoff_hist_dir,
++	    latency_hist_root);
++	for_each_possible_cpu(i) {
++		sprintf(name, cpufmt, i);
++		entry = debugfs_create_file(name, 0444, dentry,
++		    &per_cpu(preemptirqsoff_hist, i), &latency_hist_fops);
++		my_hist = &per_cpu(preemptirqsoff_hist, i);
++		atomic_set(&my_hist->hist_mode, 1);
++		my_hist->min_lat = LONG_MAX;
++	}
++	entry = debugfs_create_file("reset", 0644, dentry,
++	    (void *)PREEMPTIRQSOFF_LATENCY, &latency_hist_reset_fops);
++#endif
++
++#if defined(CONFIG_INTERRUPT_OFF_HIST) || defined(CONFIG_PREEMPT_OFF_HIST)
++	entry = debugfs_create_file("preemptirqsoff", 0644,
++	    enable_root, (void *)&preemptirqsoff_enabled_data,
++	    &enable_fops);
++#endif
++
++#ifdef CONFIG_WAKEUP_LATENCY_HIST
++	dentry = debugfs_create_dir(wakeup_latency_hist_dir,
++	    latency_hist_root);
++	dentry_sharedprio = debugfs_create_dir(
++	    wakeup_latency_hist_dir_sharedprio, dentry);
++	for_each_possible_cpu(i) {
++		sprintf(name, cpufmt, i);
++
++		entry = debugfs_create_file(name, 0444, dentry,
++		    &per_cpu(wakeup_latency_hist, i),
++		    &latency_hist_fops);
++		my_hist = &per_cpu(wakeup_latency_hist, i);
++		atomic_set(&my_hist->hist_mode, 1);
++		my_hist->min_lat = LONG_MAX;
++
++		entry = debugfs_create_file(name, 0444, dentry_sharedprio,
++		    &per_cpu(wakeup_latency_hist_sharedprio, i),
++		    &latency_hist_fops);
++		my_hist = &per_cpu(wakeup_latency_hist_sharedprio, i);
++		atomic_set(&my_hist->hist_mode, 1);
++		my_hist->min_lat = LONG_MAX;
++
++		sprintf(name, cpufmt_maxlatproc, i);
++
++		mp = &per_cpu(wakeup_maxlatproc, i);
++		entry = debugfs_create_file(name, 0444, dentry, mp,
++		    &maxlatproc_fops);
++		clear_maxlatprocdata(mp);
++
++		mp = &per_cpu(wakeup_maxlatproc_sharedprio, i);
++		entry = debugfs_create_file(name, 0444, dentry_sharedprio, mp,
++		    &maxlatproc_fops);
++		clear_maxlatprocdata(mp);
++	}
++	entry = debugfs_create_file("pid", 0644, dentry,
++	    (void *)&wakeup_pid, &pid_fops);
++	entry = debugfs_create_file("reset", 0644, dentry,
++	    (void *)WAKEUP_LATENCY, &latency_hist_reset_fops);
++	entry = debugfs_create_file("reset", 0644, dentry_sharedprio,
++	    (void *)WAKEUP_LATENCY_SHAREDPRIO, &latency_hist_reset_fops);
++	entry = debugfs_create_file("wakeup", 0644,
++	    enable_root, (void *)&wakeup_latency_enabled_data,
++	    &enable_fops);
++#endif
++
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++	dentry = debugfs_create_dir(missed_timer_offsets_dir,
++	    latency_hist_root);
++	for_each_possible_cpu(i) {
++		sprintf(name, cpufmt, i);
++		entry = debugfs_create_file(name, 0444, dentry,
++		    &per_cpu(missed_timer_offsets, i), &latency_hist_fops);
++		my_hist = &per_cpu(missed_timer_offsets, i);
++		atomic_set(&my_hist->hist_mode, 1);
++		my_hist->min_lat = LONG_MAX;
++
++		sprintf(name, cpufmt_maxlatproc, i);
++		mp = &per_cpu(missed_timer_offsets_maxlatproc, i);
++		entry = debugfs_create_file(name, 0444, dentry, mp,
++		    &maxlatproc_fops);
++		clear_maxlatprocdata(mp);
++	}
++	entry = debugfs_create_file("pid", 0644, dentry,
++	    (void *)&missed_timer_offsets_pid, &pid_fops);
++	entry = debugfs_create_file("reset", 0644, dentry,
++	    (void *)MISSED_TIMER_OFFSETS, &latency_hist_reset_fops);
++	entry = debugfs_create_file("missed_timer_offsets", 0644,
++	    enable_root, (void *)&missed_timer_offsets_enabled_data,
++	    &enable_fops);
++#endif
++
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) && \
++	defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++	dentry = debugfs_create_dir(timerandwakeup_latency_hist_dir,
++	    latency_hist_root);
++	for_each_possible_cpu(i) {
++		sprintf(name, cpufmt, i);
++		entry = debugfs_create_file(name, 0444, dentry,
++		    &per_cpu(timerandwakeup_latency_hist, i),
++		    &latency_hist_fops);
++		my_hist = &per_cpu(timerandwakeup_latency_hist, i);
++		atomic_set(&my_hist->hist_mode, 1);
++		my_hist->min_lat = LONG_MAX;
++
++		sprintf(name, cpufmt_maxlatproc, i);
++		mp = &per_cpu(timerandwakeup_maxlatproc, i);
++		entry = debugfs_create_file(name, 0444, dentry, mp,
++		    &maxlatproc_fops);
++		clear_maxlatprocdata(mp);
++	}
++	entry = debugfs_create_file("reset", 0644, dentry,
++	    (void *)TIMERANDWAKEUP_LATENCY, &latency_hist_reset_fops);
++	entry = debugfs_create_file("timerandwakeup", 0644,
++	    enable_root, (void *)&timerandwakeup_enabled_data,
++	    &enable_fops);
++#endif
++	return 0;
++}
++
++device_initcall(latency_hist_init);
+diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
+index a2f0b9f33e9b..3ffea48d795c 100644
+--- a/kernel/trace/trace.c
++++ b/kernel/trace/trace.c
+@@ -1657,6 +1657,7 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags,
+ 	struct task_struct *tsk = current;
+ 
+ 	entry->preempt_count		= pc & 0xff;
++	entry->preempt_lazy_count	= preempt_lazy_count();
+ 	entry->pid			= (tsk) ? tsk->pid : 0;
+ 	entry->flags =
+ #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
+@@ -1667,8 +1668,11 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags,
+ 		((pc & NMI_MASK    ) ? TRACE_FLAG_NMI     : 0) |
+ 		((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) |
+ 		((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) |
+-		(tif_need_resched() ? TRACE_FLAG_NEED_RESCHED : 0) |
++		(tif_need_resched_now() ? TRACE_FLAG_NEED_RESCHED : 0) |
++		(need_resched_lazy() ? TRACE_FLAG_NEED_RESCHED_LAZY : 0) |
+ 		(test_preempt_need_resched() ? TRACE_FLAG_PREEMPT_RESCHED : 0);
++
++	entry->migrate_disable = (tsk) ? __migrate_disabled(tsk) & 0xFF : 0;
+ }
+ EXPORT_SYMBOL_GPL(tracing_generic_entry_update);
+ 
+@@ -2561,14 +2565,17 @@ get_total_entries(struct trace_buffer *buf,
+ 
+ static void print_lat_help_header(struct seq_file *m)
+ {
+-	seq_puts(m, "#                  _------=> CPU#            \n"
+-		    "#                 / _-----=> irqs-off        \n"
+-		    "#                | / _----=> need-resched    \n"
+-		    "#                || / _---=> hardirq/softirq \n"
+-		    "#                ||| / _--=> preempt-depth   \n"
+-		    "#                |||| /     delay            \n"
+-		    "#  cmd     pid   ||||| time  |   caller      \n"
+-		    "#     \\   /      |||||  \\    |   /         \n");
++	seq_puts(m, "#                   _--------=> CPU#              \n"
++		    "#                  / _-------=> irqs-off          \n"
++		    "#                 | / _------=> need-resched      \n"
++		    "#                 || / _-----=> need-resched_lazy \n"
++		    "#                 ||| / _----=> hardirq/softirq   \n"
++		    "#                 |||| / _---=> preempt-depth     \n"
++		    "#                 ||||| / _--=> preempt-lazy-depth\n"
++		    "#                 |||||| / _-=> migrate-disable   \n"
++		    "#                 ||||||| /     delay             \n"
++		    "#  cmd     pid    |||||||| time  |   caller       \n"
++		    "#     \\   /      ||||||||  \\   |   /            \n");
+ }
+ 
+ static void print_event_info(struct trace_buffer *buf, struct seq_file *m)
+@@ -2594,11 +2601,14 @@ static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file
+ 	print_event_info(buf, m);
+ 	seq_puts(m, "#                              _-----=> irqs-off\n"
+ 		    "#                             / _----=> need-resched\n"
+-		    "#                            | / _---=> hardirq/softirq\n"
+-		    "#                            || / _--=> preempt-depth\n"
+-		    "#                            ||| /     delay\n"
+-		    "#           TASK-PID   CPU#  ||||    TIMESTAMP  FUNCTION\n"
+-		    "#              | |       |   ||||       |         |\n");
++		    "#                            |/  _-----=> need-resched_lazy\n"
++		    "#                            || / _---=> hardirq/softirq\n"
++		    "#                            ||| / _--=> preempt-depth\n"
++		    "#                            |||| /_--=> preempt-lazy-depth\n"
++		    "#                            |||||  _-=> migrate-disable   \n"
++		    "#                            ||||| /    delay\n"
++		    "#           TASK-PID   CPU#  ||||||    TIMESTAMP  FUNCTION\n"
++		    "#              | |       |   ||||||       |         |\n");
+ }
+ 
+ void
+diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
+index 3fff4adfd431..acb00bc2b0e0 100644
+--- a/kernel/trace/trace.h
++++ b/kernel/trace/trace.h
+@@ -117,6 +117,7 @@ struct kretprobe_trace_entry_head {
+  *  NEED_RESCHED	- reschedule is requested
+  *  HARDIRQ		- inside an interrupt handler
+  *  SOFTIRQ		- inside a softirq handler
++ *  NEED_RESCHED_LAZY	- lazy reschedule is requested
+  */
+ enum trace_flag_type {
+ 	TRACE_FLAG_IRQS_OFF		= 0x01,
+@@ -126,6 +127,7 @@ enum trace_flag_type {
+ 	TRACE_FLAG_SOFTIRQ		= 0x10,
+ 	TRACE_FLAG_PREEMPT_RESCHED	= 0x20,
+ 	TRACE_FLAG_NMI			= 0x40,
++	TRACE_FLAG_NEED_RESCHED_LAZY	= 0x80,
+ };
+ 
+ #define TRACE_BUF_SIZE		1024
+diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
+index 6f965864cc02..72a4cf8dbef5 100644
+--- a/kernel/trace/trace_events.c
++++ b/kernel/trace/trace_events.c
+@@ -188,6 +188,8 @@ static int trace_define_common_fields(void)
+ 	__common_field(unsigned char, flags);
+ 	__common_field(unsigned char, preempt_count);
+ 	__common_field(int, pid);
++	__common_field(unsigned short, migrate_disable);
++	__common_field(unsigned short, padding);
+ 
+ 	return ret;
+ }
+@@ -244,6 +246,14 @@ void *trace_event_buffer_reserve(struct trace_event_buffer *fbuffer,
+ 
+ 	local_save_flags(fbuffer->flags);
+ 	fbuffer->pc = preempt_count();
++	/*
++	 * If CONFIG_PREEMPT is enabled, then the tracepoint itself disables
++	 * preemption (adding one to the preempt_count). Since we are
++	 * interested in the preempt_count at the time the tracepoint was
++	 * hit, we need to subtract one to offset the increment.
++	 */
++	if (IS_ENABLED(CONFIG_PREEMPT))
++		fbuffer->pc--;
+ 	fbuffer->trace_file = trace_file;
+ 
+ 	fbuffer->event =
+diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
+index 03cdff84d026..940bd10b4406 100644
+--- a/kernel/trace/trace_irqsoff.c
++++ b/kernel/trace/trace_irqsoff.c
+@@ -13,6 +13,7 @@
+ #include <linux/uaccess.h>
+ #include <linux/module.h>
+ #include <linux/ftrace.h>
++#include <trace/events/hist.h>
+ 
+ #include "trace.h"
+ 
+@@ -424,11 +425,13 @@ void start_critical_timings(void)
+ {
+ 	if (preempt_trace() || irq_trace())
+ 		start_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
++	trace_preemptirqsoff_hist_rcuidle(TRACE_START, 1);
+ }
+ EXPORT_SYMBOL_GPL(start_critical_timings);
+ 
+ void stop_critical_timings(void)
+ {
++	trace_preemptirqsoff_hist_rcuidle(TRACE_STOP, 0);
+ 	if (preempt_trace() || irq_trace())
+ 		stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
+ }
+@@ -438,6 +441,7 @@ EXPORT_SYMBOL_GPL(stop_critical_timings);
+ #ifdef CONFIG_PROVE_LOCKING
+ void time_hardirqs_on(unsigned long a0, unsigned long a1)
+ {
++	trace_preemptirqsoff_hist_rcuidle(IRQS_ON, 0);
+ 	if (!preempt_trace() && irq_trace())
+ 		stop_critical_timing(a0, a1);
+ }
+@@ -446,6 +450,7 @@ void time_hardirqs_off(unsigned long a0, unsigned long a1)
+ {
+ 	if (!preempt_trace() && irq_trace())
+ 		start_critical_timing(a0, a1);
++	trace_preemptirqsoff_hist_rcuidle(IRQS_OFF, 1);
+ }
+ 
+ #else /* !CONFIG_PROVE_LOCKING */
+@@ -471,6 +476,7 @@ inline void print_irqtrace_events(struct task_struct *curr)
+  */
+ void trace_hardirqs_on(void)
+ {
++	trace_preemptirqsoff_hist(IRQS_ON, 0);
+ 	if (!preempt_trace() && irq_trace())
+ 		stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
+ }
+@@ -480,11 +486,13 @@ void trace_hardirqs_off(void)
+ {
+ 	if (!preempt_trace() && irq_trace())
+ 		start_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
++	trace_preemptirqsoff_hist(IRQS_OFF, 1);
+ }
+ EXPORT_SYMBOL(trace_hardirqs_off);
+ 
+ __visible void trace_hardirqs_on_caller(unsigned long caller_addr)
+ {
++	trace_preemptirqsoff_hist(IRQS_ON, 0);
+ 	if (!preempt_trace() && irq_trace())
+ 		stop_critical_timing(CALLER_ADDR0, caller_addr);
+ }
+@@ -494,6 +502,7 @@ __visible void trace_hardirqs_off_caller(unsigned long caller_addr)
+ {
+ 	if (!preempt_trace() && irq_trace())
+ 		start_critical_timing(CALLER_ADDR0, caller_addr);
++	trace_preemptirqsoff_hist(IRQS_OFF, 1);
+ }
+ EXPORT_SYMBOL(trace_hardirqs_off_caller);
+ 
+@@ -503,12 +512,14 @@ EXPORT_SYMBOL(trace_hardirqs_off_caller);
+ #ifdef CONFIG_PREEMPT_TRACER
+ void trace_preempt_on(unsigned long a0, unsigned long a1)
+ {
++	trace_preemptirqsoff_hist(PREEMPT_ON, 0);
+ 	if (preempt_trace() && !irq_trace())
+ 		stop_critical_timing(a0, a1);
+ }
+ 
+ void trace_preempt_off(unsigned long a0, unsigned long a1)
+ {
++	trace_preemptirqsoff_hist(PREEMPT_ON, 1);
+ 	if (preempt_trace() && !irq_trace())
+ 		start_critical_timing(a0, a1);
+ }
+diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
+index 0bb9cf2d53e6..455a7464772f 100644
+--- a/kernel/trace/trace_output.c
++++ b/kernel/trace/trace_output.c
+@@ -386,6 +386,7 @@ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
+ {
+ 	char hardsoft_irq;
+ 	char need_resched;
++	char need_resched_lazy;
+ 	char irqs_off;
+ 	int hardirq;
+ 	int softirq;
+@@ -416,6 +417,9 @@ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
+ 		break;
+ 	}
+ 
++	need_resched_lazy =
++		(entry->flags & TRACE_FLAG_NEED_RESCHED_LAZY) ? 'L' : '.';
++
+ 	hardsoft_irq =
+ 		(nmi && hardirq)     ? 'Z' :
+ 		nmi                  ? 'z' :
+@@ -424,14 +428,25 @@ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
+ 		softirq              ? 's' :
+ 		                       '.' ;
+ 
+-	trace_seq_printf(s, "%c%c%c",
+-			 irqs_off, need_resched, hardsoft_irq);
++	trace_seq_printf(s, "%c%c%c%c",
++			 irqs_off, need_resched, need_resched_lazy,
++			 hardsoft_irq);
+ 
+ 	if (entry->preempt_count)
+ 		trace_seq_printf(s, "%x", entry->preempt_count);
+ 	else
+ 		trace_seq_putc(s, '.');
+ 
++	if (entry->preempt_lazy_count)
++		trace_seq_printf(s, "%x", entry->preempt_lazy_count);
++	else
++		trace_seq_putc(s, '.');
++
++	if (entry->migrate_disable)
++		trace_seq_printf(s, "%x", entry->migrate_disable);
++	else
++		trace_seq_putc(s, '.');
++
+ 	return !trace_seq_has_overflowed(s);
+ }
+ 
+diff --git a/kernel/user.c b/kernel/user.c
+index b069ccbfb0b0..1a2e88e98b5e 100644
+--- a/kernel/user.c
++++ b/kernel/user.c
+@@ -161,11 +161,11 @@ void free_uid(struct user_struct *up)
+ 	if (!up)
+ 		return;
+ 
+-	local_irq_save(flags);
++	local_irq_save_nort(flags);
+ 	if (atomic_dec_and_lock(&up->__count, &uidhash_lock))
+ 		free_user(up, flags);
+ 	else
+-		local_irq_restore(flags);
++		local_irq_restore_nort(flags);
+ }
+ 
+ struct user_struct *alloc_uid(kuid_t uid)
+diff --git a/kernel/watchdog.c b/kernel/watchdog.c
+index 9acb29f280ec..caba62080411 100644
+--- a/kernel/watchdog.c
++++ b/kernel/watchdog.c
+@@ -315,6 +315,8 @@ static int is_softlockup(unsigned long touch_ts)
+ 
+ #ifdef CONFIG_HARDLOCKUP_DETECTOR
+ 
++static DEFINE_RAW_SPINLOCK(watchdog_output_lock);
++
+ static struct perf_event_attr wd_hw_attr = {
+ 	.type		= PERF_TYPE_HARDWARE,
+ 	.config		= PERF_COUNT_HW_CPU_CYCLES,
+@@ -349,6 +351,13 @@ static void watchdog_overflow_callback(struct perf_event *event,
+ 		/* only print hardlockups once */
+ 		if (__this_cpu_read(hard_watchdog_warn) == true)
+ 			return;
++		/*
++		 * If early-printk is enabled then make sure we do not
++		 * lock up in printk() and kill console logging:
++		 */
++		printk_kill();
++
++		raw_spin_lock(&watchdog_output_lock);
+ 
+ 		pr_emerg("Watchdog detected hard LOCKUP on cpu %d", this_cpu);
+ 		print_modules();
+@@ -366,6 +375,7 @@ static void watchdog_overflow_callback(struct perf_event *event,
+ 				!test_and_set_bit(0, &hardlockup_allcpu_dumped))
+ 			trigger_allbutself_cpu_backtrace();
+ 
++		raw_spin_unlock(&watchdog_output_lock);
+ 		if (hardlockup_panic)
+ 			nmi_panic(regs, "Hard LOCKUP");
+ 
+@@ -513,6 +523,7 @@ static void watchdog_enable(unsigned int cpu)
+ 	/* kick off the timer for the hardlockup detector */
+ 	hrtimer_init(hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ 	hrtimer->function = watchdog_timer_fn;
++	hrtimer->irqsafe = 1;
+ 
+ 	/* Enable the perf event */
+ 	watchdog_nmi_enable(cpu);
+diff --git a/kernel/workqueue.c b/kernel/workqueue.c
+index 5f5068e94003..54fd5dfb05b1 100644
+--- a/kernel/workqueue.c
++++ b/kernel/workqueue.c
+@@ -48,6 +48,8 @@
+ #include <linux/nodemask.h>
+ #include <linux/moduleparam.h>
+ #include <linux/uaccess.h>
++#include <linux/locallock.h>
++#include <linux/delay.h>
+ 
+ #include "workqueue_internal.h"
+ 
+@@ -121,11 +123,16 @@ enum {
+  *    cpu or grabbing pool->lock is enough for read access.  If
+  *    POOL_DISASSOCIATED is set, it's identical to L.
+  *
++ *    On RT we need the extra protection via rt_lock_idle_list() for
++ *    the list manipulations against read access from
++ *    wq_worker_sleeping(). All other places are nicely serialized via
++ *    pool->lock.
++ *
+  * A: pool->attach_mutex protected.
+  *
+  * PL: wq_pool_mutex protected.
+  *
+- * PR: wq_pool_mutex protected for writes.  Sched-RCU protected for reads.
++ * PR: wq_pool_mutex protected for writes.  RCU protected for reads.
+  *
+  * PW: wq_pool_mutex and wq->mutex protected for writes.  Either for reads.
+  *
+@@ -134,7 +141,7 @@ enum {
+  *
+  * WQ: wq->mutex protected.
+  *
+- * WR: wq->mutex protected for writes.  Sched-RCU protected for reads.
++ * WR: wq->mutex protected for writes.  RCU protected for reads.
+  *
+  * MD: wq_mayday_lock protected.
+  */
+@@ -185,7 +192,7 @@ struct worker_pool {
+ 	atomic_t		nr_running ____cacheline_aligned_in_smp;
+ 
+ 	/*
+-	 * Destruction of pool is sched-RCU protected to allow dereferences
++	 * Destruction of pool is RCU protected to allow dereferences
+ 	 * from get_work_pool().
+ 	 */
+ 	struct rcu_head		rcu;
+@@ -214,7 +221,7 @@ struct pool_workqueue {
+ 	/*
+ 	 * Release of unbound pwq is punted to system_wq.  See put_pwq()
+ 	 * and pwq_unbound_release_workfn() for details.  pool_workqueue
+-	 * itself is also sched-RCU protected so that the first pwq can be
++	 * itself is also RCU protected so that the first pwq can be
+ 	 * determined without grabbing wq->mutex.
+ 	 */
+ 	struct work_struct	unbound_release_work;
+@@ -348,6 +355,8 @@ EXPORT_SYMBOL_GPL(system_power_efficient_wq);
+ struct workqueue_struct *system_freezable_power_efficient_wq __read_mostly;
+ EXPORT_SYMBOL_GPL(system_freezable_power_efficient_wq);
+ 
++static DEFINE_LOCAL_IRQ_LOCK(pendingb_lock);
++
+ static int worker_thread(void *__worker);
+ static void workqueue_sysfs_unregister(struct workqueue_struct *wq);
+ 
+@@ -355,20 +364,20 @@ static void workqueue_sysfs_unregister(struct workqueue_struct *wq);
+ #include <trace/events/workqueue.h>
+ 
+ #define assert_rcu_or_pool_mutex()					\
+-	RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held() &&			\
++	RCU_LOCKDEP_WARN(!rcu_read_lock_held() &&			\
+ 			 !lockdep_is_held(&wq_pool_mutex),		\
+-			 "sched RCU or wq_pool_mutex should be held")
++			 "RCU or wq_pool_mutex should be held")
+ 
+ #define assert_rcu_or_wq_mutex(wq)					\
+-	RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held() &&			\
++	RCU_LOCKDEP_WARN(!rcu_read_lock_held() &&			\
+ 			 !lockdep_is_held(&wq->mutex),			\
+-			 "sched RCU or wq->mutex should be held")
++			 "RCU or wq->mutex should be held")
+ 
+ #define assert_rcu_or_wq_mutex_or_pool_mutex(wq)			\
+-	RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held() &&			\
++	RCU_LOCKDEP_WARN(!rcu_read_lock_held() &&			\
+ 			 !lockdep_is_held(&wq->mutex) &&		\
+ 			 !lockdep_is_held(&wq_pool_mutex),		\
+-			 "sched RCU, wq->mutex or wq_pool_mutex should be held")
++			 "RCU, wq->mutex or wq_pool_mutex should be held")
+ 
+ #define for_each_cpu_worker_pool(pool, cpu)				\
+ 	for ((pool) = &per_cpu(cpu_worker_pools, cpu)[0];		\
+@@ -380,7 +389,7 @@ static void workqueue_sysfs_unregister(struct workqueue_struct *wq);
+  * @pool: iteration cursor
+  * @pi: integer used for iteration
+  *
+- * This must be called either with wq_pool_mutex held or sched RCU read
++ * This must be called either with wq_pool_mutex held or RCU read
+  * locked.  If the pool needs to be used beyond the locking in effect, the
+  * caller is responsible for guaranteeing that the pool stays online.
+  *
+@@ -412,7 +421,7 @@ static void workqueue_sysfs_unregister(struct workqueue_struct *wq);
+  * @pwq: iteration cursor
+  * @wq: the target workqueue
+  *
+- * This must be called either with wq->mutex held or sched RCU read locked.
++ * This must be called either with wq->mutex held or RCU read locked.
+  * If the pwq needs to be used beyond the locking in effect, the caller is
+  * responsible for guaranteeing that the pwq stays online.
+  *
+@@ -424,6 +433,31 @@ static void workqueue_sysfs_unregister(struct workqueue_struct *wq);
+ 		if (({ assert_rcu_or_wq_mutex(wq); false; })) { }	\
+ 		else
+ 
++#ifdef CONFIG_PREEMPT_RT_BASE
++static inline void rt_lock_idle_list(struct worker_pool *pool)
++{
++	preempt_disable();
++}
++static inline void rt_unlock_idle_list(struct worker_pool *pool)
++{
++	preempt_enable();
++}
++static inline void sched_lock_idle_list(struct worker_pool *pool) { }
++static inline void sched_unlock_idle_list(struct worker_pool *pool) { }
++#else
++static inline void rt_lock_idle_list(struct worker_pool *pool) { }
++static inline void rt_unlock_idle_list(struct worker_pool *pool) { }
++static inline void sched_lock_idle_list(struct worker_pool *pool)
++{
++	spin_lock_irq(&pool->lock);
++}
++static inline void sched_unlock_idle_list(struct worker_pool *pool)
++{
++	spin_unlock_irq(&pool->lock);
++}
++#endif
++
++
+ #ifdef CONFIG_DEBUG_OBJECTS_WORK
+ 
+ static struct debug_obj_descr work_debug_descr;
+@@ -574,7 +608,7 @@ static int worker_pool_assign_id(struct worker_pool *pool)
+  * @wq: the target workqueue
+  * @node: the node ID
+  *
+- * This must be called with any of wq_pool_mutex, wq->mutex or sched RCU
++ * This must be called with any of wq_pool_mutex, wq->mutex or RCU
+  * read locked.
+  * If the pwq needs to be used beyond the locking in effect, the caller is
+  * responsible for guaranteeing that the pwq stays online.
+@@ -718,8 +752,8 @@ static struct pool_workqueue *get_work_pwq(struct work_struct *work)
+  * @work: the work item of interest
+  *
+  * Pools are created and destroyed under wq_pool_mutex, and allows read
+- * access under sched-RCU read lock.  As such, this function should be
+- * called under wq_pool_mutex or with preemption disabled.
++ * access under RCU read lock.  As such, this function should be
++ * called under wq_pool_mutex or inside of a rcu_read_lock() region.
+  *
+  * All fields of the returned pool are accessible as long as the above
+  * mentioned locking is in effect.  If the returned pool needs to be used
+@@ -856,50 +890,45 @@ static struct worker *first_idle_worker(struct worker_pool *pool)
+  */
+ static void wake_up_worker(struct worker_pool *pool)
+ {
+-	struct worker *worker = first_idle_worker(pool);
++	struct worker *worker;
++
++	rt_lock_idle_list(pool);
++
++	worker = first_idle_worker(pool);
+ 
+ 	if (likely(worker))
+ 		wake_up_process(worker->task);
++
++	rt_unlock_idle_list(pool);
+ }
+ 
+ /**
+- * wq_worker_waking_up - a worker is waking up
+- * @task: task waking up
++ * wq_worker_running - a worker is running again
+  * @cpu: CPU @task is waking up to
+  *
+- * This function is called during try_to_wake_up() when a worker is
+- * being awoken.
+- *
+- * CONTEXT:
+- * spin_lock_irq(rq->lock)
++ * This function is called when a worker returns from schedule()
+  */
+-void wq_worker_waking_up(struct task_struct *task, int cpu)
++void wq_worker_running(struct task_struct *task)
+ {
+ 	struct worker *worker = kthread_data(task);
+ 
+-	if (!(worker->flags & WORKER_NOT_RUNNING)) {
+-		WARN_ON_ONCE(worker->pool->cpu != cpu);
++	if (!worker->sleeping)
++		return;
++	if (!(worker->flags & WORKER_NOT_RUNNING))
+ 		atomic_inc(&worker->pool->nr_running);
+-	}
++	worker->sleeping = 0;
+ }
+ 
+ /**
+  * wq_worker_sleeping - a worker is going to sleep
+  * @task: task going to sleep
+  *
+- * This function is called during schedule() when a busy worker is
+- * going to sleep.  Worker on the same cpu can be woken up by
+- * returning pointer to its task.
+- *
+- * CONTEXT:
+- * spin_lock_irq(rq->lock)
+- *
+- * Return:
+- * Worker task on @cpu to wake up, %NULL if none.
++ * This function is called from schedule() when a busy worker is
++ * going to sleep.
+  */
+-struct task_struct *wq_worker_sleeping(struct task_struct *task)
++void wq_worker_sleeping(struct task_struct *task)
+ {
+-	struct worker *worker = kthread_data(task), *to_wakeup = NULL;
++	struct worker *worker = kthread_data(task);
+ 	struct worker_pool *pool;
+ 
+ 	/*
+@@ -908,29 +937,26 @@ struct task_struct *wq_worker_sleeping(struct task_struct *task)
+ 	 * checking NOT_RUNNING.
+ 	 */
+ 	if (worker->flags & WORKER_NOT_RUNNING)
+-		return NULL;
++		return;
+ 
+ 	pool = worker->pool;
+ 
+-	/* this can only happen on the local cpu */
+-	if (WARN_ON_ONCE(pool->cpu != raw_smp_processor_id()))
+-		return NULL;
++	if (WARN_ON_ONCE(worker->sleeping))
++		return;
++
++	worker->sleeping = 1;
+ 
+ 	/*
+ 	 * The counterpart of the following dec_and_test, implied mb,
+ 	 * worklist not empty test sequence is in insert_work().
+ 	 * Please read comment there.
+-	 *
+-	 * NOT_RUNNING is clear.  This means that we're bound to and
+-	 * running on the local cpu w/ rq lock held and preemption
+-	 * disabled, which in turn means that none else could be
+-	 * manipulating idle_list, so dereferencing idle_list without pool
+-	 * lock is safe.
+ 	 */
+ 	if (atomic_dec_and_test(&pool->nr_running) &&
+-	    !list_empty(&pool->worklist))
+-		to_wakeup = first_idle_worker(pool);
+-	return to_wakeup ? to_wakeup->task : NULL;
++	    !list_empty(&pool->worklist)) {
++		sched_lock_idle_list(pool);
++		wake_up_worker(pool);
++		sched_unlock_idle_list(pool);
++	}
+ }
+ 
+ /**
+@@ -1124,12 +1150,12 @@ static void put_pwq_unlocked(struct pool_workqueue *pwq)
+ {
+ 	if (pwq) {
+ 		/*
+-		 * As both pwqs and pools are sched-RCU protected, the
++		 * As both pwqs and pools are RCU protected, the
+ 		 * following lock operations are safe.
+ 		 */
+-		spin_lock_irq(&pwq->pool->lock);
++		local_spin_lock_irq(pendingb_lock, &pwq->pool->lock);
+ 		put_pwq(pwq);
+-		spin_unlock_irq(&pwq->pool->lock);
++		local_spin_unlock_irq(pendingb_lock, &pwq->pool->lock);
+ 	}
+ }
+ 
+@@ -1233,7 +1259,7 @@ static int try_to_grab_pending(struct work_struct *work, bool is_dwork,
+ 	struct worker_pool *pool;
+ 	struct pool_workqueue *pwq;
+ 
+-	local_irq_save(*flags);
++	local_lock_irqsave(pendingb_lock, *flags);
+ 
+ 	/* try to steal the timer if it exists */
+ 	if (is_dwork) {
+@@ -1252,6 +1278,7 @@ static int try_to_grab_pending(struct work_struct *work, bool is_dwork,
+ 	if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work)))
+ 		return 0;
+ 
++	rcu_read_lock();
+ 	/*
+ 	 * The queueing is in progress, or it is already queued. Try to
+ 	 * steal it from ->worklist without clearing WORK_STRUCT_PENDING.
+@@ -1290,14 +1317,16 @@ static int try_to_grab_pending(struct work_struct *work, bool is_dwork,
+ 		set_work_pool_and_keep_pending(work, pool->id);
+ 
+ 		spin_unlock(&pool->lock);
++		rcu_read_unlock();
+ 		return 1;
+ 	}
+ 	spin_unlock(&pool->lock);
+ fail:
+-	local_irq_restore(*flags);
++	rcu_read_unlock();
++	local_unlock_irqrestore(pendingb_lock, *flags);
+ 	if (work_is_canceling(work))
+ 		return -ENOENT;
+-	cpu_relax();
++	cpu_chill();
+ 	return -EAGAIN;
+ }
+ 
+@@ -1399,7 +1428,7 @@ static void __queue_work(int cpu, struct workqueue_struct *wq,
+ 	 * queued or lose PENDING.  Grabbing PENDING and queueing should
+ 	 * happen with IRQ disabled.
+ 	 */
+-	WARN_ON_ONCE(!irqs_disabled());
++	WARN_ON_ONCE_NONRT(!irqs_disabled());
+ 
+ 	debug_work_activate(work);
+ 
+@@ -1407,6 +1436,7 @@ static void __queue_work(int cpu, struct workqueue_struct *wq,
+ 	if (unlikely(wq->flags & __WQ_DRAINING) &&
+ 	    WARN_ON_ONCE(!is_chained_work(wq)))
+ 		return;
++	rcu_read_lock();
+ retry:
+ 	if (req_cpu == WORK_CPU_UNBOUND)
+ 		cpu = wq_select_unbound_cpu(raw_smp_processor_id());
+@@ -1463,10 +1493,8 @@ static void __queue_work(int cpu, struct workqueue_struct *wq,
+ 	/* pwq determined, queue */
+ 	trace_workqueue_queue_work(req_cpu, pwq, work);
+ 
+-	if (WARN_ON(!list_empty(&work->entry))) {
+-		spin_unlock(&pwq->pool->lock);
+-		return;
+-	}
++	if (WARN_ON(!list_empty(&work->entry)))
++		goto out;
+ 
+ 	pwq->nr_in_flight[pwq->work_color]++;
+ 	work_flags = work_color_to_flags(pwq->work_color);
+@@ -1484,7 +1512,9 @@ static void __queue_work(int cpu, struct workqueue_struct *wq,
+ 
+ 	insert_work(pwq, work, worklist, work_flags);
+ 
++out:
+ 	spin_unlock(&pwq->pool->lock);
++	rcu_read_unlock();
+ }
+ 
+ /**
+@@ -1504,14 +1534,14 @@ bool queue_work_on(int cpu, struct workqueue_struct *wq,
+ 	bool ret = false;
+ 	unsigned long flags;
+ 
+-	local_irq_save(flags);
++	local_lock_irqsave(pendingb_lock,flags);
+ 
+ 	if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))) {
+ 		__queue_work(cpu, wq, work);
+ 		ret = true;
+ 	}
+ 
+-	local_irq_restore(flags);
++	local_unlock_irqrestore(pendingb_lock, flags);
+ 	return ret;
+ }
+ EXPORT_SYMBOL(queue_work_on);
+@@ -1578,14 +1608,14 @@ bool queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
+ 	unsigned long flags;
+ 
+ 	/* read the comment in __queue_work() */
+-	local_irq_save(flags);
++	local_lock_irqsave(pendingb_lock, flags);
+ 
+ 	if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))) {
+ 		__queue_delayed_work(cpu, wq, dwork, delay);
+ 		ret = true;
+ 	}
+ 
+-	local_irq_restore(flags);
++	local_unlock_irqrestore(pendingb_lock, flags);
+ 	return ret;
+ }
+ EXPORT_SYMBOL(queue_delayed_work_on);
+@@ -1620,7 +1650,7 @@ bool mod_delayed_work_on(int cpu, struct workqueue_struct *wq,
+ 
+ 	if (likely(ret >= 0)) {
+ 		__queue_delayed_work(cpu, wq, dwork, delay);
+-		local_irq_restore(flags);
++		local_unlock_irqrestore(pendingb_lock, flags);
+ 	}
+ 
+ 	/* -ENOENT from try_to_grab_pending() becomes %true */
+@@ -1653,7 +1683,9 @@ static void worker_enter_idle(struct worker *worker)
+ 	worker->last_active = jiffies;
+ 
+ 	/* idle_list is LIFO */
++	rt_lock_idle_list(pool);
+ 	list_add(&worker->entry, &pool->idle_list);
++	rt_unlock_idle_list(pool);
+ 
+ 	if (too_many_workers(pool) && !timer_pending(&pool->idle_timer))
+ 		mod_timer(&pool->idle_timer, jiffies + IDLE_WORKER_TIMEOUT);
+@@ -1686,7 +1718,9 @@ static void worker_leave_idle(struct worker *worker)
+ 		return;
+ 	worker_clr_flags(worker, WORKER_IDLE);
+ 	pool->nr_idle--;
++	rt_lock_idle_list(pool);
+ 	list_del_init(&worker->entry);
++	rt_unlock_idle_list(pool);
+ }
+ 
+ static struct worker *alloc_worker(int node)
+@@ -1852,7 +1886,9 @@ static void destroy_worker(struct worker *worker)
+ 	pool->nr_workers--;
+ 	pool->nr_idle--;
+ 
++	rt_lock_idle_list(pool);
+ 	list_del_init(&worker->entry);
++	rt_unlock_idle_list(pool);
+ 	worker->flags |= WORKER_DIE;
+ 	wake_up_process(worker->task);
+ }
+@@ -2811,14 +2847,14 @@ static bool start_flush_work(struct work_struct *work, struct wq_barrier *barr)
+ 
+ 	might_sleep();
+ 
+-	local_irq_disable();
++	rcu_read_lock();
+ 	pool = get_work_pool(work);
+ 	if (!pool) {
+-		local_irq_enable();
++		rcu_read_unlock();
+ 		return false;
+ 	}
+ 
+-	spin_lock(&pool->lock);
++	spin_lock_irq(&pool->lock);
+ 	/* see the comment in try_to_grab_pending() with the same code */
+ 	pwq = get_work_pwq(work);
+ 	if (pwq) {
+@@ -2847,10 +2883,11 @@ static bool start_flush_work(struct work_struct *work, struct wq_barrier *barr)
+ 	else
+ 		lock_map_acquire_read(&pwq->wq->lockdep_map);
+ 	lock_map_release(&pwq->wq->lockdep_map);
+-
++	rcu_read_unlock();
+ 	return true;
+ already_gone:
+ 	spin_unlock_irq(&pool->lock);
++	rcu_read_unlock();
+ 	return false;
+ }
+ 
+@@ -2937,7 +2974,7 @@ static bool __cancel_work_timer(struct work_struct *work, bool is_dwork)
+ 
+ 	/* tell other tasks trying to grab @work to back off */
+ 	mark_work_canceling(work);
+-	local_irq_restore(flags);
++	local_unlock_irqrestore(pendingb_lock, flags);
+ 
+ 	flush_work(work);
+ 	clear_work_data(work);
+@@ -2992,10 +3029,10 @@ EXPORT_SYMBOL_GPL(cancel_work_sync);
+  */
+ bool flush_delayed_work(struct delayed_work *dwork)
+ {
+-	local_irq_disable();
++	local_lock_irq(pendingb_lock);
+ 	if (del_timer_sync(&dwork->timer))
+ 		__queue_work(dwork->cpu, dwork->wq, &dwork->work);
+-	local_irq_enable();
++	local_unlock_irq(pendingb_lock);
+ 	return flush_work(&dwork->work);
+ }
+ EXPORT_SYMBOL(flush_delayed_work);
+@@ -3030,7 +3067,7 @@ bool cancel_delayed_work(struct delayed_work *dwork)
+ 
+ 	set_work_pool_and_clear_pending(&dwork->work,
+ 					get_work_pool_id(&dwork->work));
+-	local_irq_restore(flags);
++	local_unlock_irqrestore(pendingb_lock, flags);
+ 	return ret;
+ }
+ EXPORT_SYMBOL(cancel_delayed_work);
+@@ -3259,7 +3296,7 @@ static void rcu_free_pool(struct rcu_head *rcu)
+  * put_unbound_pool - put a worker_pool
+  * @pool: worker_pool to put
+  *
+- * Put @pool.  If its refcnt reaches zero, it gets destroyed in sched-RCU
++ * Put @pool.  If its refcnt reaches zero, it gets destroyed in RCU
+  * safe manner.  get_unbound_pool() calls this function on its failure path
+  * and this function should be able to release pools which went through,
+  * successfully or not, init_worker_pool().
+@@ -3313,8 +3350,8 @@ static void put_unbound_pool(struct worker_pool *pool)
+ 	del_timer_sync(&pool->idle_timer);
+ 	del_timer_sync(&pool->mayday_timer);
+ 
+-	/* sched-RCU protected to allow dereferences from get_work_pool() */
+-	call_rcu_sched(&pool->rcu, rcu_free_pool);
++	/* RCU protected to allow dereferences from get_work_pool() */
++	call_rcu(&pool->rcu, rcu_free_pool);
+ }
+ 
+ /**
+@@ -3421,14 +3458,14 @@ static void pwq_unbound_release_workfn(struct work_struct *work)
+ 	put_unbound_pool(pool);
+ 	mutex_unlock(&wq_pool_mutex);
+ 
+-	call_rcu_sched(&pwq->rcu, rcu_free_pwq);
++	call_rcu(&pwq->rcu, rcu_free_pwq);
+ 
+ 	/*
+ 	 * If we're the last pwq going away, @wq is already dead and no one
+ 	 * is gonna access it anymore.  Schedule RCU free.
+ 	 */
+ 	if (is_last)
+-		call_rcu_sched(&wq->rcu, rcu_free_wq);
++		call_rcu(&wq->rcu, rcu_free_wq);
+ }
+ 
+ /**
+@@ -4078,7 +4115,7 @@ void destroy_workqueue(struct workqueue_struct *wq)
+ 		 * The base ref is never dropped on per-cpu pwqs.  Directly
+ 		 * schedule RCU free.
+ 		 */
+-		call_rcu_sched(&wq->rcu, rcu_free_wq);
++		call_rcu(&wq->rcu, rcu_free_wq);
+ 	} else {
+ 		/*
+ 		 * We're the sole accessor of @wq at this point.  Directly
+@@ -4171,7 +4208,8 @@ bool workqueue_congested(int cpu, struct workqueue_struct *wq)
+ 	struct pool_workqueue *pwq;
+ 	bool ret;
+ 
+-	rcu_read_lock_sched();
++	rcu_read_lock();
++	preempt_disable();
+ 
+ 	if (cpu == WORK_CPU_UNBOUND)
+ 		cpu = smp_processor_id();
+@@ -4182,7 +4220,8 @@ bool workqueue_congested(int cpu, struct workqueue_struct *wq)
+ 		pwq = unbound_pwq_by_node(wq, cpu_to_node(cpu));
+ 
+ 	ret = !list_empty(&pwq->delayed_works);
+-	rcu_read_unlock_sched();
++	preempt_enable();
++	rcu_read_unlock();
+ 
+ 	return ret;
+ }
+@@ -4208,15 +4247,15 @@ unsigned int work_busy(struct work_struct *work)
+ 	if (work_pending(work))
+ 		ret |= WORK_BUSY_PENDING;
+ 
+-	local_irq_save(flags);
++	rcu_read_lock();
+ 	pool = get_work_pool(work);
+ 	if (pool) {
+-		spin_lock(&pool->lock);
++		spin_lock_irqsave(&pool->lock, flags);
+ 		if (find_worker_executing_work(pool, work))
+ 			ret |= WORK_BUSY_RUNNING;
+-		spin_unlock(&pool->lock);
++		spin_unlock_irqrestore(&pool->lock, flags);
+ 	}
+-	local_irq_restore(flags);
++	rcu_read_unlock();
+ 
+ 	return ret;
+ }
+@@ -4405,7 +4444,7 @@ void show_workqueue_state(void)
+ 	unsigned long flags;
+ 	int pi;
+ 
+-	rcu_read_lock_sched();
++	rcu_read_lock();
+ 
+ 	pr_info("Showing busy workqueues and worker pools:\n");
+ 
+@@ -4458,7 +4497,7 @@ void show_workqueue_state(void)
+ 		spin_unlock_irqrestore(&pool->lock, flags);
+ 	}
+ 
+-	rcu_read_unlock_sched();
++	rcu_read_unlock();
+ }
+ 
+ /*
+@@ -4819,16 +4858,16 @@ bool freeze_workqueues_busy(void)
+ 		 * nr_active is monotonically decreasing.  It's safe
+ 		 * to peek without lock.
+ 		 */
+-		rcu_read_lock_sched();
++		rcu_read_lock();
+ 		for_each_pwq(pwq, wq) {
+ 			WARN_ON_ONCE(pwq->nr_active < 0);
+ 			if (pwq->nr_active) {
+ 				busy = true;
+-				rcu_read_unlock_sched();
++				rcu_read_unlock();
+ 				goto out_unlock;
+ 			}
+ 		}
+-		rcu_read_unlock_sched();
++		rcu_read_unlock();
+ 	}
+ out_unlock:
+ 	mutex_unlock(&wq_pool_mutex);
+@@ -5018,7 +5057,8 @@ static ssize_t wq_pool_ids_show(struct device *dev,
+ 	const char *delim = "";
+ 	int node, written = 0;
+ 
+-	rcu_read_lock_sched();
++	get_online_cpus();
++	rcu_read_lock();
+ 	for_each_node(node) {
+ 		written += scnprintf(buf + written, PAGE_SIZE - written,
+ 				     "%s%d:%d", delim, node,
+@@ -5026,7 +5066,8 @@ static ssize_t wq_pool_ids_show(struct device *dev,
+ 		delim = " ";
+ 	}
+ 	written += scnprintf(buf + written, PAGE_SIZE - written, "\n");
+-	rcu_read_unlock_sched();
++	rcu_read_unlock();
++	put_online_cpus();
+ 
+ 	return written;
+ }
+diff --git a/kernel/workqueue_internal.h b/kernel/workqueue_internal.h
+index 8635417c587b..f000c4d6917e 100644
+--- a/kernel/workqueue_internal.h
++++ b/kernel/workqueue_internal.h
+@@ -43,6 +43,7 @@ struct worker {
+ 	unsigned long		last_active;	/* L: last active timestamp */
+ 	unsigned int		flags;		/* X: flags */
+ 	int			id;		/* I: worker id */
++	int			sleeping;	/* None */
+ 
+ 	/*
+ 	 * Opaque string set with work_set_desc().  Printed out with task
+@@ -68,7 +69,7 @@ static inline struct worker *current_wq_worker(void)
+  * Scheduler hooks for concurrency managed workqueue.  Only to be used from
+  * sched/core.c and workqueue.c.
+  */
+-void wq_worker_waking_up(struct task_struct *task, int cpu);
+-struct task_struct *wq_worker_sleeping(struct task_struct *task);
++void wq_worker_running(struct task_struct *task);
++void wq_worker_sleeping(struct task_struct *task);
+ 
+ #endif /* _KERNEL_WORKQUEUE_INTERNAL_H */
+diff --git a/lib/Kconfig b/lib/Kconfig
+index 3cca1222578e..b89fc373331f 100644
+--- a/lib/Kconfig
++++ b/lib/Kconfig
+@@ -397,6 +397,7 @@ config CHECK_SIGNATURE
+ 
+ config CPUMASK_OFFSTACK
+ 	bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS
++	depends on !PREEMPT_RT_FULL
+ 	help
+ 	  Use dynamic allocation for cpumask_var_t, instead of putting
+ 	  them on the stack.  This is a bit more expensive, but avoids
+diff --git a/lib/debugobjects.c b/lib/debugobjects.c
+index 519b5a10fd70..5970701e8f1e 100644
+--- a/lib/debugobjects.c
++++ b/lib/debugobjects.c
+@@ -309,7 +309,10 @@ __debug_object_init(void *addr, struct debug_obj_descr *descr, int onstack)
+ 	struct debug_obj *obj;
+ 	unsigned long flags;
+ 
+-	fill_pool();
++#ifdef CONFIG_PREEMPT_RT_FULL
++	if (preempt_count() == 0 && !irqs_disabled())
++#endif
++		fill_pool();
+ 
+ 	db = get_bucket((unsigned long) addr);
+ 
+diff --git a/lib/idr.c b/lib/idr.c
+index 6098336df267..9decbe914595 100644
+--- a/lib/idr.c
++++ b/lib/idr.c
+@@ -30,6 +30,7 @@
+ #include <linux/idr.h>
+ #include <linux/spinlock.h>
+ #include <linux/percpu.h>
++#include <linux/locallock.h>
+ 
+ #define MAX_IDR_SHIFT		(sizeof(int) * 8 - 1)
+ #define MAX_IDR_BIT		(1U << MAX_IDR_SHIFT)
+@@ -45,6 +46,37 @@ static DEFINE_PER_CPU(struct idr_layer *, idr_preload_head);
+ static DEFINE_PER_CPU(int, idr_preload_cnt);
+ static DEFINE_SPINLOCK(simple_ida_lock);
+ 
++#ifdef CONFIG_PREEMPT_RT_FULL
++static DEFINE_LOCAL_IRQ_LOCK(idr_lock);
++
++static inline void idr_preload_lock(void)
++{
++	local_lock(idr_lock);
++}
++
++static inline void idr_preload_unlock(void)
++{
++	local_unlock(idr_lock);
++}
++
++void idr_preload_end(void)
++{
++	idr_preload_unlock();
++}
++EXPORT_SYMBOL(idr_preload_end);
++#else
++static inline void idr_preload_lock(void)
++{
++	preempt_disable();
++}
++
++static inline void idr_preload_unlock(void)
++{
++	preempt_enable();
++}
++#endif
++
++
+ /* the maximum ID which can be allocated given idr->layers */
+ static int idr_max(int layers)
+ {
+@@ -115,14 +147,14 @@ static struct idr_layer *idr_layer_alloc(gfp_t gfp_mask, struct idr *layer_idr)
+ 	 * context.  See idr_preload() for details.
+ 	 */
+ 	if (!in_interrupt()) {
+-		preempt_disable();
++		idr_preload_lock();
+ 		new = __this_cpu_read(idr_preload_head);
+ 		if (new) {
+ 			__this_cpu_write(idr_preload_head, new->ary[0]);
+ 			__this_cpu_dec(idr_preload_cnt);
+ 			new->ary[0] = NULL;
+ 		}
+-		preempt_enable();
++		idr_preload_unlock();
+ 		if (new)
+ 			return new;
+ 	}
+@@ -366,7 +398,6 @@ static void idr_fill_slot(struct idr *idr, void *ptr, int id,
+ 	idr_mark_full(pa, id);
+ }
+ 
+-
+ /**
+  * idr_preload - preload for idr_alloc()
+  * @gfp_mask: allocation mask to use for preloading
+@@ -401,7 +432,7 @@ void idr_preload(gfp_t gfp_mask)
+ 	WARN_ON_ONCE(in_interrupt());
+ 	might_sleep_if(gfpflags_allow_blocking(gfp_mask));
+ 
+-	preempt_disable();
++	idr_preload_lock();
+ 
+ 	/*
+ 	 * idr_alloc() is likely to succeed w/o full idr_layer buffer and
+@@ -413,9 +444,9 @@ void idr_preload(gfp_t gfp_mask)
+ 	while (__this_cpu_read(idr_preload_cnt) < MAX_IDR_FREE) {
+ 		struct idr_layer *new;
+ 
+-		preempt_enable();
++		idr_preload_unlock();
+ 		new = kmem_cache_zalloc(idr_layer_cache, gfp_mask);
+-		preempt_disable();
++		idr_preload_lock();
+ 		if (!new)
+ 			break;
+ 
+diff --git a/lib/irq_poll.c b/lib/irq_poll.c
+index 836f7db4e548..709d4eed1df9 100644
+--- a/lib/irq_poll.c
++++ b/lib/irq_poll.c
+@@ -36,6 +36,7 @@ void irq_poll_sched(struct irq_poll *iop)
+ 	list_add_tail(&iop->list, this_cpu_ptr(&blk_cpu_iopoll));
+ 	__raise_softirq_irqoff(IRQ_POLL_SOFTIRQ);
+ 	local_irq_restore(flags);
++	preempt_check_resched_rt();
+ }
+ EXPORT_SYMBOL(irq_poll_sched);
+ 
+@@ -71,6 +72,7 @@ void irq_poll_complete(struct irq_poll *iop)
+ 	local_irq_save(flags);
+ 	__irq_poll_complete(iop);
+ 	local_irq_restore(flags);
++	preempt_check_resched_rt();
+ }
+ EXPORT_SYMBOL(irq_poll_complete);
+ 
+@@ -95,6 +97,7 @@ static void irq_poll_softirq(struct softirq_action *h)
+ 		}
+ 
+ 		local_irq_enable();
++		preempt_check_resched_rt();
+ 
+ 		/* Even though interrupts have been re-enabled, this
+ 		 * access is safe because interrupts can only add new
+@@ -132,6 +135,7 @@ static void irq_poll_softirq(struct softirq_action *h)
+ 		__raise_softirq_irqoff(IRQ_POLL_SOFTIRQ);
+ 
+ 	local_irq_enable();
++	preempt_check_resched_rt();
+ }
+ 
+ /**
+@@ -199,6 +203,7 @@ static int irq_poll_cpu_notify(struct notifier_block *self,
+ 				 this_cpu_ptr(&blk_cpu_iopoll));
+ 		__raise_softirq_irqoff(IRQ_POLL_SOFTIRQ);
+ 		local_irq_enable();
++		preempt_check_resched_rt();
+ 	}
+ 
+ 	return NOTIFY_OK;
+diff --git a/lib/locking-selftest.c b/lib/locking-selftest.c
+index 872a15a2a637..b93a6103fa4d 100644
+--- a/lib/locking-selftest.c
++++ b/lib/locking-selftest.c
+@@ -590,6 +590,8 @@ GENERATE_TESTCASE(init_held_rsem)
+ #include "locking-selftest-spin-hardirq.h"
+ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_spin)
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
++
+ #include "locking-selftest-rlock-hardirq.h"
+ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_rlock)
+ 
+@@ -605,9 +607,12 @@ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_rlock)
+ #include "locking-selftest-wlock-softirq.h"
+ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_wlock)
+ 
++#endif
++
+ #undef E1
+ #undef E2
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
+ /*
+  * Enabling hardirqs with a softirq-safe lock held:
+  */
+@@ -640,6 +645,8 @@ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_rlock)
+ #undef E1
+ #undef E2
+ 
++#endif
++
+ /*
+  * Enabling irqs with an irq-safe lock held:
+  */
+@@ -663,6 +670,8 @@ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_rlock)
+ #include "locking-selftest-spin-hardirq.h"
+ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_spin)
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
++
+ #include "locking-selftest-rlock-hardirq.h"
+ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_rlock)
+ 
+@@ -678,6 +687,8 @@ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_rlock)
+ #include "locking-selftest-wlock-softirq.h"
+ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_wlock)
+ 
++#endif
++
+ #undef E1
+ #undef E2
+ 
+@@ -709,6 +720,8 @@ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_wlock)
+ #include "locking-selftest-spin-hardirq.h"
+ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_spin)
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
++
+ #include "locking-selftest-rlock-hardirq.h"
+ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_rlock)
+ 
+@@ -724,6 +737,8 @@ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_rlock)
+ #include "locking-selftest-wlock-softirq.h"
+ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_wlock)
+ 
++#endif
++
+ #undef E1
+ #undef E2
+ #undef E3
+@@ -757,6 +772,8 @@ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_wlock)
+ #include "locking-selftest-spin-hardirq.h"
+ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_spin)
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
++
+ #include "locking-selftest-rlock-hardirq.h"
+ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_rlock)
+ 
+@@ -772,10 +789,14 @@ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_rlock)
+ #include "locking-selftest-wlock-softirq.h"
+ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_wlock)
+ 
++#endif
++
+ #undef E1
+ #undef E2
+ #undef E3
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
++
+ /*
+  * read-lock / write-lock irq inversion.
+  *
+@@ -838,6 +859,10 @@ GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_soft_wlock)
+ #undef E2
+ #undef E3
+ 
++#endif
++
++#ifndef CONFIG_PREEMPT_RT_FULL
++
+ /*
+  * read-lock / write-lock recursion that is actually safe.
+  */
+@@ -876,6 +901,8 @@ GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion_soft)
+ #undef E2
+ #undef E3
+ 
++#endif
++
+ /*
+  * read-lock / write-lock recursion that is unsafe.
+  */
+@@ -1858,6 +1885,7 @@ void locking_selftest(void)
+ 
+ 	printk("  --------------------------------------------------------------------------\n");
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
+ 	/*
+ 	 * irq-context testcases:
+ 	 */
+@@ -1870,6 +1898,28 @@ void locking_selftest(void)
+ 
+ 	DO_TESTCASE_6x2("irq read-recursion", irq_read_recursion);
+ //	DO_TESTCASE_6x2B("irq read-recursion #2", irq_read_recursion2);
++#else
++	/* On -rt, we only do hardirq context test for raw spinlock */
++	DO_TESTCASE_1B("hard-irqs-on + irq-safe-A", irqsafe1_hard_spin, 12);
++	DO_TESTCASE_1B("hard-irqs-on + irq-safe-A", irqsafe1_hard_spin, 21);
++
++	DO_TESTCASE_1B("hard-safe-A + irqs-on", irqsafe2B_hard_spin, 12);
++	DO_TESTCASE_1B("hard-safe-A + irqs-on", irqsafe2B_hard_spin, 21);
++
++	DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 123);
++	DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 132);
++	DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 213);
++	DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 231);
++	DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 312);
++	DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 321);
++
++	DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 123);
++	DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 132);
++	DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 213);
++	DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 231);
++	DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 312);
++	DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 321);
++#endif
+ 
+ 	ww_tests();
+ 
+diff --git a/lib/percpu_ida.c b/lib/percpu_ida.c
+index 6d40944960de..822a2c027e72 100644
+--- a/lib/percpu_ida.c
++++ b/lib/percpu_ida.c
+@@ -26,6 +26,9 @@
+ #include <linux/string.h>
+ #include <linux/spinlock.h>
+ #include <linux/percpu_ida.h>
++#include <linux/locallock.h>
++
++static DEFINE_LOCAL_IRQ_LOCK(irq_off_lock);
+ 
+ struct percpu_ida_cpu {
+ 	/*
+@@ -148,13 +151,13 @@ int percpu_ida_alloc(struct percpu_ida *pool, int state)
+ 	unsigned long flags;
+ 	int tag;
+ 
+-	local_irq_save(flags);
++	local_lock_irqsave(irq_off_lock, flags);
+ 	tags = this_cpu_ptr(pool->tag_cpu);
+ 
+ 	/* Fastpath */
+ 	tag = alloc_local_tag(tags);
+ 	if (likely(tag >= 0)) {
+-		local_irq_restore(flags);
++		local_unlock_irqrestore(irq_off_lock, flags);
+ 		return tag;
+ 	}
+ 
+@@ -173,6 +176,7 @@ int percpu_ida_alloc(struct percpu_ida *pool, int state)
+ 
+ 		if (!tags->nr_free)
+ 			alloc_global_tags(pool, tags);
++
+ 		if (!tags->nr_free)
+ 			steal_tags(pool, tags);
+ 
+@@ -184,7 +188,7 @@ int percpu_ida_alloc(struct percpu_ida *pool, int state)
+ 		}
+ 
+ 		spin_unlock(&pool->lock);
+-		local_irq_restore(flags);
++		local_unlock_irqrestore(irq_off_lock, flags);
+ 
+ 		if (tag >= 0 || state == TASK_RUNNING)
+ 			break;
+@@ -196,7 +200,7 @@ int percpu_ida_alloc(struct percpu_ida *pool, int state)
+ 
+ 		schedule();
+ 
+-		local_irq_save(flags);
++		local_lock_irqsave(irq_off_lock, flags);
+ 		tags = this_cpu_ptr(pool->tag_cpu);
+ 	}
+ 	if (state != TASK_RUNNING)
+@@ -221,7 +225,7 @@ void percpu_ida_free(struct percpu_ida *pool, unsigned tag)
+ 
+ 	BUG_ON(tag >= pool->nr_tags);
+ 
+-	local_irq_save(flags);
++	local_lock_irqsave(irq_off_lock, flags);
+ 	tags = this_cpu_ptr(pool->tag_cpu);
+ 
+ 	spin_lock(&tags->lock);
+@@ -253,7 +257,7 @@ void percpu_ida_free(struct percpu_ida *pool, unsigned tag)
+ 		spin_unlock(&pool->lock);
+ 	}
+ 
+-	local_irq_restore(flags);
++	local_unlock_irqrestore(irq_off_lock, flags);
+ }
+ EXPORT_SYMBOL_GPL(percpu_ida_free);
+ 
+@@ -345,7 +349,7 @@ int percpu_ida_for_each_free(struct percpu_ida *pool, percpu_ida_cb fn,
+ 	struct percpu_ida_cpu *remote;
+ 	unsigned cpu, i, err = 0;
+ 
+-	local_irq_save(flags);
++	local_lock_irqsave(irq_off_lock, flags);
+ 	for_each_possible_cpu(cpu) {
+ 		remote = per_cpu_ptr(pool->tag_cpu, cpu);
+ 		spin_lock(&remote->lock);
+@@ -367,7 +371,7 @@ int percpu_ida_for_each_free(struct percpu_ida *pool, percpu_ida_cb fn,
+ 	}
+ 	spin_unlock(&pool->lock);
+ out:
+-	local_irq_restore(flags);
++	local_unlock_irqrestore(irq_off_lock, flags);
+ 	return err;
+ }
+ EXPORT_SYMBOL_GPL(percpu_ida_for_each_free);
+diff --git a/lib/radix-tree.c b/lib/radix-tree.c
+index 1624c4117961..5f53e83b2859 100644
+--- a/lib/radix-tree.c
++++ b/lib/radix-tree.c
+@@ -240,13 +240,14 @@ radix_tree_node_alloc(struct radix_tree_root *root)
+ 		 * succeed in getting a node here (and never reach
+ 		 * kmem_cache_alloc)
+ 		 */
+-		rtp = this_cpu_ptr(&radix_tree_preloads);
++		rtp = &get_cpu_var(radix_tree_preloads);
+ 		if (rtp->nr) {
+ 			ret = rtp->nodes;
+ 			rtp->nodes = ret->private_data;
+ 			ret->private_data = NULL;
+ 			rtp->nr--;
+ 		}
++		put_cpu_var(radix_tree_preloads);
+ 		/*
+ 		 * Update the allocation stack trace as this is more useful
+ 		 * for debugging.
+@@ -287,6 +288,7 @@ radix_tree_node_free(struct radix_tree_node *node)
+ 	call_rcu(&node->rcu_head, radix_tree_node_rcu_free);
+ }
+ 
++#ifndef CONFIG_PREEMPT_RT_FULL
+ /*
+  * Load up this CPU's radix_tree_node buffer with sufficient objects to
+  * ensure that the addition of a single element in the tree cannot fail.  On
+@@ -355,6 +357,7 @@ int radix_tree_maybe_preload(gfp_t gfp_mask)
+ 	return 0;
+ }
+ EXPORT_SYMBOL(radix_tree_maybe_preload);
++#endif
+ 
+ /*
+  *	Return the maximum key which can be store into a
+diff --git a/lib/random32.c b/lib/random32.c
+index 510d1ce7d4d2..69ed593aab07 100644
+--- a/lib/random32.c
++++ b/lib/random32.c
+@@ -233,7 +233,6 @@ static void __prandom_timer(unsigned long dontcare)
+ 
+ static void __init __prandom_start_seed_timer(void)
+ {
+-	set_timer_slack(&seed_timer, HZ);
+ 	seed_timer.expires = jiffies + msecs_to_jiffies(40 * MSEC_PER_SEC);
+ 	add_timer(&seed_timer);
+ }
+diff --git a/lib/rbtree.c b/lib/rbtree.c
+index 1356454e36de..d15d6c4327f1 100644
+--- a/lib/rbtree.c
++++ b/lib/rbtree.c
+@@ -23,6 +23,7 @@
+ 
+ #include <linux/rbtree_augmented.h>
+ #include <linux/export.h>
++#include <linux/rcupdate.h>
+ 
+ /*
+  * red-black trees properties:  http://en.wikipedia.org/wiki/Rbtree
+@@ -590,3 +591,13 @@ struct rb_node *rb_first_postorder(const struct rb_root *root)
+ 	return rb_left_deepest_node(root->rb_node);
+ }
+ EXPORT_SYMBOL(rb_first_postorder);
++
++void rb_link_node_rcu(struct rb_node *node, struct rb_node *parent,
++				    struct rb_node **rb_link)
++{
++	node->__rb_parent_color = (unsigned long)parent;
++	node->rb_left = node->rb_right = NULL;
++
++	rcu_assign_pointer(*rb_link, node);
++}
++EXPORT_SYMBOL(rb_link_node_rcu);
+diff --git a/lib/scatterlist.c b/lib/scatterlist.c
+index 004fc70fc56a..ccc46992a517 100644
+--- a/lib/scatterlist.c
++++ b/lib/scatterlist.c
+@@ -620,7 +620,7 @@ void sg_miter_stop(struct sg_mapping_iter *miter)
+ 			flush_kernel_dcache_page(miter->page);
+ 
+ 		if (miter->__flags & SG_MITER_ATOMIC) {
+-			WARN_ON_ONCE(preemptible());
++			WARN_ON_ONCE(!pagefault_disabled());
+ 			kunmap_atomic(miter->addr);
+ 		} else
+ 			kunmap(miter->page);
+@@ -664,7 +664,7 @@ size_t sg_copy_buffer(struct scatterlist *sgl, unsigned int nents, void *buf,
+ 	if (!sg_miter_skip(&miter, skip))
+ 		return false;
+ 
+-	local_irq_save(flags);
++	local_irq_save_nort(flags);
+ 
+ 	while (sg_miter_next(&miter) && offset < buflen) {
+ 		unsigned int len;
+@@ -681,7 +681,7 @@ size_t sg_copy_buffer(struct scatterlist *sgl, unsigned int nents, void *buf,
+ 
+ 	sg_miter_stop(&miter);
+ 
+-	local_irq_restore(flags);
++	local_irq_restore_nort(flags);
+ 	return offset;
+ }
+ EXPORT_SYMBOL(sg_copy_buffer);
+diff --git a/lib/smp_processor_id.c b/lib/smp_processor_id.c
+index 1afec32de6f2..11fa431046a8 100644
+--- a/lib/smp_processor_id.c
++++ b/lib/smp_processor_id.c
+@@ -39,8 +39,9 @@ notrace static unsigned int check_preemption_disabled(const char *what1,
+ 	if (!printk_ratelimit())
+ 		goto out_enable;
+ 
+-	printk(KERN_ERR "BUG: using %s%s() in preemptible [%08x] code: %s/%d\n",
+-		what1, what2, preempt_count() - 1, current->comm, current->pid);
++	printk(KERN_ERR "BUG: using %s%s() in preemptible [%08x %08x] code: %s/%d\n",
++		what1, what2, preempt_count() - 1, __migrate_disabled(current),
++		current->comm, current->pid);
+ 
+ 	print_symbol("caller is %s\n", (long)__builtin_return_address(0));
+ 	dump_stack();
+diff --git a/mm/Kconfig b/mm/Kconfig
+index 989f8f3d77e0..1df53d6c7ec5 100644
+--- a/mm/Kconfig
++++ b/mm/Kconfig
+@@ -391,7 +391,7 @@ config NOMMU_INITIAL_TRIM_EXCESS
+ 
+ config TRANSPARENT_HUGEPAGE
+ 	bool "Transparent Hugepage Support"
+-	depends on HAVE_ARCH_TRANSPARENT_HUGEPAGE
++	depends on HAVE_ARCH_TRANSPARENT_HUGEPAGE && !PREEMPT_RT_FULL
+ 	select COMPACTION
+ 	help
+ 	  Transparent Hugepages allows the kernel to use huge pages and
+diff --git a/mm/backing-dev.c b/mm/backing-dev.c
+index 0c6317b7db38..1e6ab5fbadb4 100644
+--- a/mm/backing-dev.c
++++ b/mm/backing-dev.c
+@@ -457,9 +457,9 @@ void wb_congested_put(struct bdi_writeback_congested *congested)
+ {
+ 	unsigned long flags;
+ 
+-	local_irq_save(flags);
++	local_irq_save_nort(flags);
+ 	if (!atomic_dec_and_lock(&congested->refcnt, &cgwb_lock)) {
+-		local_irq_restore(flags);
++		local_irq_restore_nort(flags);
+ 		return;
+ 	}
+ 
+diff --git a/mm/compaction.c b/mm/compaction.c
+index f8e925eb479b..14cfc4714e57 100644
+--- a/mm/compaction.c
++++ b/mm/compaction.c
+@@ -1414,10 +1414,12 @@ static int compact_zone(struct zone *zone, struct compact_control *cc)
+ 				cc->migrate_pfn & ~((1UL << cc->order) - 1);
+ 
+ 			if (cc->last_migrated_pfn < current_block_start) {
+-				cpu = get_cpu();
++				cpu = get_cpu_light();
++				local_lock_irq(swapvec_lock);
+ 				lru_add_drain_cpu(cpu);
++				local_unlock_irq(swapvec_lock);
+ 				drain_local_pages(zone);
+-				put_cpu();
++				put_cpu_light();
+ 				/* No more flushing until we migrate again */
+ 				cc->last_migrated_pfn = 0;
+ 			}
+diff --git a/mm/filemap.c b/mm/filemap.c
+index f2479af09da9..a87b65c2e402 100644
+--- a/mm/filemap.c
++++ b/mm/filemap.c
+@@ -169,7 +169,9 @@ static void page_cache_tree_delete(struct address_space *mapping,
+ 	if (!workingset_node_pages(node) &&
+ 	    list_empty(&node->private_list)) {
+ 		node->private_data = mapping;
+-		list_lru_add(&workingset_shadow_nodes, &node->private_list);
++		local_lock(workingset_shadow_lock);
++		list_lru_add(&__workingset_shadow_nodes, &node->private_list);
++		local_unlock(workingset_shadow_lock);
+ 	}
+ }
+ 
+@@ -618,9 +620,12 @@ static int page_cache_tree_insert(struct address_space *mapping,
+ 		 * node->private_list is protected by
+ 		 * mapping->tree_lock.
+ 		 */
+-		if (!list_empty(&node->private_list))
+-			list_lru_del(&workingset_shadow_nodes,
++		if (!list_empty(&node->private_list)) {
++			local_lock(workingset_shadow_lock);
++			list_lru_del(&__workingset_shadow_nodes,
+ 				     &node->private_list);
++			local_unlock(workingset_shadow_lock);
++		}
+ 	}
+ 	return 0;
+ }
+diff --git a/mm/highmem.c b/mm/highmem.c
+index 123bcd3ed4f2..16e8cf26d38a 100644
+--- a/mm/highmem.c
++++ b/mm/highmem.c
+@@ -29,10 +29,11 @@
+ #include <linux/kgdb.h>
+ #include <asm/tlbflush.h>
+ 
+-
++#ifndef CONFIG_PREEMPT_RT_FULL
+ #if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32)
+ DEFINE_PER_CPU(int, __kmap_atomic_idx);
+ #endif
++#endif
+ 
+ /*
+  * Virtual_count is not a pure "count".
+@@ -107,8 +108,9 @@ static inline wait_queue_head_t *get_pkmap_wait_queue_head(unsigned int color)
+ unsigned long totalhigh_pages __read_mostly;
+ EXPORT_SYMBOL(totalhigh_pages);
+ 
+-
++#ifndef CONFIG_PREEMPT_RT_FULL
+ EXPORT_PER_CPU_SYMBOL(__kmap_atomic_idx);
++#endif
+ 
+ unsigned int nr_free_highpages (void)
+ {
+diff --git a/mm/memcontrol.c b/mm/memcontrol.c
+index a2e79b83920f..9764ec471f4d 100644
+--- a/mm/memcontrol.c
++++ b/mm/memcontrol.c
+@@ -67,6 +67,7 @@
+ #include <net/sock.h>
+ #include <net/ip.h>
+ #include "slab.h"
++#include <linux/locallock.h>
+ 
+ #include <asm/uaccess.h>
+ 
+@@ -92,6 +93,8 @@ int do_swap_account __read_mostly;
+ #define do_swap_account		0
+ #endif
+ 
++static DEFINE_LOCAL_IRQ_LOCK(event_lock);
++
+ /* Whether legacy memory+swap accounting is active */
+ static bool do_memsw_account(void)
+ {
+@@ -1825,14 +1828,17 @@ static void drain_local_stock(struct work_struct *dummy)
+  */
+ static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages)
+ {
+-	struct memcg_stock_pcp *stock = &get_cpu_var(memcg_stock);
++	struct memcg_stock_pcp *stock;
++	int cpu = get_cpu_light();
++
++	stock = &per_cpu(memcg_stock, cpu);
+ 
+ 	if (stock->cached != memcg) { /* reset if necessary */
+ 		drain_stock(stock);
+ 		stock->cached = memcg;
+ 	}
+ 	stock->nr_pages += nr_pages;
+-	put_cpu_var(memcg_stock);
++	put_cpu_light();
+ }
+ 
+ /*
+@@ -1848,7 +1854,7 @@ static void drain_all_stock(struct mem_cgroup *root_memcg)
+ 		return;
+ 	/* Notify other cpus that system-wide "drain" is running */
+ 	get_online_cpus();
+-	curcpu = get_cpu();
++	curcpu = get_cpu_light();
+ 	for_each_online_cpu(cpu) {
+ 		struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu);
+ 		struct mem_cgroup *memcg;
+@@ -1865,7 +1871,7 @@ static void drain_all_stock(struct mem_cgroup *root_memcg)
+ 				schedule_work_on(cpu, &stock->work);
+ 		}
+ 	}
+-	put_cpu();
++	put_cpu_light();
+ 	put_online_cpus();
+ 	mutex_unlock(&percpu_charge_mutex);
+ }
+@@ -4487,12 +4493,12 @@ static int mem_cgroup_move_account(struct page *page,
+ 
+ 	ret = 0;
+ 
+-	local_irq_disable();
++	local_lock_irq(event_lock);
+ 	mem_cgroup_charge_statistics(to, page, compound, nr_pages);
+ 	memcg_check_events(to, page);
+ 	mem_cgroup_charge_statistics(from, page, compound, -nr_pages);
+ 	memcg_check_events(from, page);
+-	local_irq_enable();
++	local_unlock_irq(event_lock);
+ out_unlock:
+ 	unlock_page(page);
+ out:
+@@ -5342,10 +5348,10 @@ void mem_cgroup_commit_charge(struct page *page, struct mem_cgroup *memcg,
+ 
+ 	commit_charge(page, memcg, lrucare);
+ 
+-	local_irq_disable();
++	local_lock_irq(event_lock);
+ 	mem_cgroup_charge_statistics(memcg, page, compound, nr_pages);
+ 	memcg_check_events(memcg, page);
+-	local_irq_enable();
++	local_unlock_irq(event_lock);
+ 
+ 	if (do_memsw_account() && PageSwapCache(page)) {
+ 		swp_entry_t entry = { .val = page_private(page) };
+@@ -5397,14 +5403,14 @@ static void uncharge_batch(struct mem_cgroup *memcg, unsigned long pgpgout,
+ 		memcg_oom_recover(memcg);
+ 	}
+ 
+-	local_irq_save(flags);
++	local_lock_irqsave(event_lock, flags);
+ 	__this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_RSS], nr_anon);
+ 	__this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_CACHE], nr_file);
+ 	__this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_RSS_HUGE], nr_huge);
+ 	__this_cpu_add(memcg->stat->events[MEM_CGROUP_EVENTS_PGPGOUT], pgpgout);
+ 	__this_cpu_add(memcg->stat->nr_page_events, nr_pages);
+ 	memcg_check_events(memcg, dummy_page);
+-	local_irq_restore(flags);
++	local_unlock_irqrestore(event_lock, flags);
+ 
+ 	if (!mem_cgroup_is_root(memcg))
+ 		css_put_many(&memcg->css, nr_pages);
+@@ -5554,10 +5560,10 @@ void mem_cgroup_migrate(struct page *oldpage, struct page *newpage)
+ 
+ 	commit_charge(newpage, memcg, false);
+ 
+-	local_irq_disable();
++	local_lock_irq(event_lock);
+ 	mem_cgroup_charge_statistics(memcg, newpage, compound, nr_pages);
+ 	memcg_check_events(memcg, newpage);
+-	local_irq_enable();
++	local_unlock_irq(event_lock);
+ }
+ 
+ DEFINE_STATIC_KEY_FALSE(memcg_sockets_enabled_key);
+@@ -5722,6 +5728,7 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
+ {
+ 	struct mem_cgroup *memcg;
+ 	unsigned short oldid;
++	unsigned long flags;
+ 
+ 	VM_BUG_ON_PAGE(PageLRU(page), page);
+ 	VM_BUG_ON_PAGE(page_count(page), page);
+@@ -5750,9 +5757,13 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
+ 	 * important here to have the interrupts disabled because it is the
+ 	 * only synchronisation we have for udpating the per-CPU variables.
+ 	 */
++	local_lock_irqsave(event_lock, flags);
++#ifndef CONFIG_PREEMPT_RT_BASE
+ 	VM_BUG_ON(!irqs_disabled());
++#endif
+ 	mem_cgroup_charge_statistics(memcg, page, false, -1);
+ 	memcg_check_events(memcg, page);
++	local_unlock_irqrestore(event_lock, flags);
+ }
+ 
+ /*
+diff --git a/mm/mmu_context.c b/mm/mmu_context.c
+index f802c2d216a7..b1b6f238e42d 100644
+--- a/mm/mmu_context.c
++++ b/mm/mmu_context.c
+@@ -23,6 +23,7 @@ void use_mm(struct mm_struct *mm)
+ 	struct task_struct *tsk = current;
+ 
+ 	task_lock(tsk);
++	preempt_disable_rt();
+ 	active_mm = tsk->active_mm;
+ 	if (active_mm != mm) {
+ 		atomic_inc(&mm->mm_count);
+@@ -30,6 +31,7 @@ void use_mm(struct mm_struct *mm)
+ 	}
+ 	tsk->mm = mm;
+ 	switch_mm(active_mm, mm, tsk);
++	preempt_enable_rt();
+ 	task_unlock(tsk);
+ #ifdef finish_arch_post_lock_switch
+ 	finish_arch_post_lock_switch();
+diff --git a/mm/page_alloc.c b/mm/page_alloc.c
+index 898fe3f909f9..301140302ff8 100644
+--- a/mm/page_alloc.c
++++ b/mm/page_alloc.c
+@@ -61,6 +61,7 @@
+ #include <linux/page_ext.h>
+ #include <linux/hugetlb.h>
+ #include <linux/sched/rt.h>
++#include <linux/locallock.h>
+ #include <linux/page_owner.h>
+ #include <linux/kthread.h>
+ 
+@@ -275,6 +276,18 @@ EXPORT_SYMBOL(nr_node_ids);
+ EXPORT_SYMBOL(nr_online_nodes);
+ #endif
+ 
++static DEFINE_LOCAL_IRQ_LOCK(pa_lock);
++
++#ifdef CONFIG_PREEMPT_RT_BASE
++# define cpu_lock_irqsave(cpu, flags)		\
++	local_lock_irqsave_on(pa_lock, flags, cpu)
++# define cpu_unlock_irqrestore(cpu, flags)	\
++	local_unlock_irqrestore_on(pa_lock, flags, cpu)
++#else
++# define cpu_lock_irqsave(cpu, flags)		local_irq_save(flags)
++# define cpu_unlock_irqrestore(cpu, flags)	local_irq_restore(flags)
++#endif
++
+ int page_group_by_mobility_disabled __read_mostly;
+ 
+ #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
+@@ -814,7 +827,7 @@ static inline int free_pages_check(struct page *page)
+ }
+ 
+ /*
+- * Frees a number of pages from the PCP lists
++ * Frees a number of pages which have been collected from the pcp lists.
+  * Assumes all pages on list are in same zone, and of same order.
+  * count is the number of pages to free.
+  *
+@@ -825,18 +838,53 @@ static inline int free_pages_check(struct page *page)
+  * pinned" detection logic.
+  */
+ static void free_pcppages_bulk(struct zone *zone, int count,
+-					struct per_cpu_pages *pcp)
++			       struct list_head *list)
+ {
+-	int migratetype = 0;
+-	int batch_free = 0;
+ 	int to_free = count;
+ 	unsigned long nr_scanned;
++	unsigned long flags;
++
++	spin_lock_irqsave(&zone->lock, flags);
+ 
+-	spin_lock(&zone->lock);
+ 	nr_scanned = zone_page_state(zone, NR_PAGES_SCANNED);
+ 	if (nr_scanned)
+ 		__mod_zone_page_state(zone, NR_PAGES_SCANNED, -nr_scanned);
+ 
++	while (!list_empty(list)) {
++		struct page *page = list_first_entry(list, struct page, lru);
++		int mt;	/* migratetype of the to-be-freed page */
++
++		/* must delete as __free_one_page list manipulates */
++		list_del(&page->lru);
++
++		mt = get_pcppage_migratetype(page);
++		/* MIGRATE_ISOLATE page should not go to pcplists */
++		VM_BUG_ON_PAGE(is_migrate_isolate(mt), page);
++		/* Pageblock could have been isolated meanwhile */
++		if (unlikely(has_isolate_pageblock(zone)))
++			mt = get_pageblock_migratetype(page);
++
++		__free_one_page(page, page_to_pfn(page), zone, 0, mt);
++		trace_mm_page_pcpu_drain(page, 0, mt);
++		to_free--;
++	}
++	WARN_ON(to_free != 0);
++	spin_unlock_irqrestore(&zone->lock, flags);
++}
++
++/*
++ * Moves a number of pages from the PCP lists to free list which
++ * is freed outside of the locked region.
++ *
++ * Assumes all pages on list are in same zone, and of same order.
++ * count is the number of pages to free.
++ */
++static void isolate_pcp_pages(int to_free, struct per_cpu_pages *src,
++			      struct list_head *dst)
++{
++	int migratetype = 0;
++	int batch_free = 0;
++
+ 	while (to_free) {
+ 		struct page *page;
+ 		struct list_head *list;
+@@ -852,7 +900,7 @@ static void free_pcppages_bulk(struct zone *zone, int count,
+ 			batch_free++;
+ 			if (++migratetype == MIGRATE_PCPTYPES)
+ 				migratetype = 0;
+-			list = &pcp->lists[migratetype];
++			list = &src->lists[migratetype];
+ 		} while (list_empty(list));
+ 
+ 		/* This is the only non-empty list. Free them all. */
+@@ -860,24 +908,12 @@ static void free_pcppages_bulk(struct zone *zone, int count,
+ 			batch_free = to_free;
+ 
+ 		do {
+-			int mt;	/* migratetype of the to-be-freed page */
+-
+ 			page = list_last_entry(list, struct page, lru);
+-			/* must delete as __free_one_page list manipulates */
+ 			list_del(&page->lru);
+ 
+-			mt = get_pcppage_migratetype(page);
+-			/* MIGRATE_ISOLATE page should not go to pcplists */
+-			VM_BUG_ON_PAGE(is_migrate_isolate(mt), page);
+-			/* Pageblock could have been isolated meanwhile */
+-			if (unlikely(has_isolate_pageblock(zone)))
+-				mt = get_pageblock_migratetype(page);
+-
+-			__free_one_page(page, page_to_pfn(page), zone, 0, mt);
+-			trace_mm_page_pcpu_drain(page, 0, mt);
++			list_add(&page->lru, dst);
+ 		} while (--to_free && --batch_free && !list_empty(list));
+ 	}
+-	spin_unlock(&zone->lock);
+ }
+ 
+ static void free_one_page(struct zone *zone,
+@@ -886,7 +922,9 @@ static void free_one_page(struct zone *zone,
+ 				int migratetype)
+ {
+ 	unsigned long nr_scanned;
+-	spin_lock(&zone->lock);
++	unsigned long flags;
++
++	spin_lock_irqsave(&zone->lock, flags);
+ 	nr_scanned = zone_page_state(zone, NR_PAGES_SCANNED);
+ 	if (nr_scanned)
+ 		__mod_zone_page_state(zone, NR_PAGES_SCANNED, -nr_scanned);
+@@ -896,7 +934,7 @@ static void free_one_page(struct zone *zone,
+ 		migratetype = get_pfnblock_migratetype(page, pfn);
+ 	}
+ 	__free_one_page(page, pfn, zone, order, migratetype);
+-	spin_unlock(&zone->lock);
++	spin_unlock_irqrestore(&zone->lock, flags);
+ }
+ 
+ static int free_tail_pages_check(struct page *head_page, struct page *page)
+@@ -1070,10 +1108,10 @@ static void __free_pages_ok(struct page *page, unsigned int order)
+ 		return;
+ 
+ 	migratetype = get_pfnblock_migratetype(page, pfn);
+-	local_irq_save(flags);
++	local_lock_irqsave(pa_lock, flags);
+ 	__count_vm_events(PGFREE, 1 << order);
+ 	free_one_page(page_zone(page), page, pfn, order, migratetype);
+-	local_irq_restore(flags);
++	local_unlock_irqrestore(pa_lock, flags);
+ }
+ 
+ static void __init __free_pages_boot_core(struct page *page,
+@@ -2015,16 +2053,18 @@ static int rmqueue_bulk(struct zone *zone, unsigned int order,
+ void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp)
+ {
+ 	unsigned long flags;
++	LIST_HEAD(dst);
+ 	int to_drain, batch;
+ 
+-	local_irq_save(flags);
++	local_lock_irqsave(pa_lock, flags);
+ 	batch = READ_ONCE(pcp->batch);
+ 	to_drain = min(pcp->count, batch);
+ 	if (to_drain > 0) {
+-		free_pcppages_bulk(zone, to_drain, pcp);
++		isolate_pcp_pages(to_drain, pcp, &dst);
+ 		pcp->count -= to_drain;
+ 	}
+-	local_irq_restore(flags);
++	local_unlock_irqrestore(pa_lock, flags);
++	free_pcppages_bulk(zone, to_drain, &dst);
+ }
+ #endif
+ 
+@@ -2040,16 +2080,21 @@ static void drain_pages_zone(unsigned int cpu, struct zone *zone)
+ 	unsigned long flags;
+ 	struct per_cpu_pageset *pset;
+ 	struct per_cpu_pages *pcp;
++	LIST_HEAD(dst);
++	int count;
+ 
+-	local_irq_save(flags);
++	cpu_lock_irqsave(cpu, flags);
+ 	pset = per_cpu_ptr(zone->pageset, cpu);
+ 
+ 	pcp = &pset->pcp;
+-	if (pcp->count) {
+-		free_pcppages_bulk(zone, pcp->count, pcp);
++	count = pcp->count;
++	if (count) {
++		isolate_pcp_pages(count, pcp, &dst);
+ 		pcp->count = 0;
+ 	}
+-	local_irq_restore(flags);
++	cpu_unlock_irqrestore(cpu, flags);
++	if (count)
++		free_pcppages_bulk(zone, count, &dst);
+ }
+ 
+ /*
+@@ -2135,8 +2180,17 @@ void drain_all_pages(struct zone *zone)
+ 		else
+ 			cpumask_clear_cpu(cpu, &cpus_with_pcps);
+ 	}
++#ifndef CONFIG_PREEMPT_RT_BASE
+ 	on_each_cpu_mask(&cpus_with_pcps, (smp_call_func_t) drain_local_pages,
+ 								zone, 1);
++#else
++	for_each_cpu(cpu, &cpus_with_pcps) {
++		if (zone)
++			drain_pages_zone(cpu, zone);
++		else
++			drain_pages(cpu);
++	}
++#endif
+ }
+ 
+ #ifdef CONFIG_HIBERNATION
+@@ -2192,7 +2246,7 @@ void free_hot_cold_page(struct page *page, bool cold)
+ 
+ 	migratetype = get_pfnblock_migratetype(page, pfn);
+ 	set_pcppage_migratetype(page, migratetype);
+-	local_irq_save(flags);
++	local_lock_irqsave(pa_lock, flags);
+ 	__count_vm_event(PGFREE);
+ 
+ 	/*
+@@ -2218,12 +2272,17 @@ void free_hot_cold_page(struct page *page, bool cold)
+ 	pcp->count++;
+ 	if (pcp->count >= pcp->high) {
+ 		unsigned long batch = READ_ONCE(pcp->batch);
+-		free_pcppages_bulk(zone, batch, pcp);
++		LIST_HEAD(dst);
++
++		isolate_pcp_pages(batch, pcp, &dst);
+ 		pcp->count -= batch;
++		local_unlock_irqrestore(pa_lock, flags);
++		free_pcppages_bulk(zone, batch, &dst);
++		return;
+ 	}
+ 
+ out:
+-	local_irq_restore(flags);
++	local_unlock_irqrestore(pa_lock, flags);
+ }
+ 
+ /*
+@@ -2358,7 +2417,7 @@ struct page *buffered_rmqueue(struct zone *preferred_zone,
+ 		struct per_cpu_pages *pcp;
+ 		struct list_head *list;
+ 
+-		local_irq_save(flags);
++		local_lock_irqsave(pa_lock, flags);
+ 		pcp = &this_cpu_ptr(zone->pageset)->pcp;
+ 		list = &pcp->lists[migratetype];
+ 		if (list_empty(list)) {
+@@ -2382,7 +2441,7 @@ struct page *buffered_rmqueue(struct zone *preferred_zone,
+ 		 * allocate greater than order-1 page units with __GFP_NOFAIL.
+ 		 */
+ 		WARN_ON_ONCE((gfp_flags & __GFP_NOFAIL) && (order > 1));
+-		spin_lock_irqsave(&zone->lock, flags);
++		local_spin_lock_irqsave(pa_lock, &zone->lock, flags);
+ 
+ 		page = NULL;
+ 		if (alloc_flags & ALLOC_HARDER) {
+@@ -2392,11 +2451,13 @@ struct page *buffered_rmqueue(struct zone *preferred_zone,
+ 		}
+ 		if (!page)
+ 			page = __rmqueue(zone, order, migratetype);
+-		spin_unlock(&zone->lock);
+-		if (!page)
++		if (!page) {
++			spin_unlock(&zone->lock);
+ 			goto failed;
++		}
+ 		__mod_zone_freepage_state(zone, -(1 << order),
+ 					  get_pcppage_migratetype(page));
++		spin_unlock(&zone->lock);
+ 	}
+ 
+ 	__mod_zone_page_state(zone, NR_ALLOC_BATCH, -(1 << order));
+@@ -2406,13 +2467,13 @@ struct page *buffered_rmqueue(struct zone *preferred_zone,
+ 
+ 	__count_zone_vm_events(PGALLOC, zone, 1 << order);
+ 	zone_statistics(preferred_zone, zone, gfp_flags);
+-	local_irq_restore(flags);
++	local_unlock_irqrestore(pa_lock, flags);
+ 
+ 	VM_BUG_ON_PAGE(bad_range(zone, page), page);
+ 	return page;
+ 
+ failed:
+-	local_irq_restore(flags);
++	local_unlock_irqrestore(pa_lock, flags);
+ 	return NULL;
+ }
+ 
+@@ -6213,7 +6274,9 @@ static int page_alloc_cpu_notify(struct notifier_block *self,
+ 	int cpu = (unsigned long)hcpu;
+ 
+ 	if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) {
++		local_lock_irq_on(swapvec_lock, cpu);
+ 		lru_add_drain_cpu(cpu);
++		local_unlock_irq_on(swapvec_lock, cpu);
+ 		drain_pages(cpu);
+ 
+ 		/*
+@@ -6239,6 +6302,7 @@ static int page_alloc_cpu_notify(struct notifier_block *self,
+ void __init page_alloc_init(void)
+ {
+ 	hotcpu_notifier(page_alloc_cpu_notify, 0);
++	local_irq_lock_init(pa_lock);
+ }
+ 
+ /*
+@@ -7163,7 +7227,7 @@ void zone_pcp_reset(struct zone *zone)
+ 	struct per_cpu_pageset *pset;
+ 
+ 	/* avoid races with drain_pages()  */
+-	local_irq_save(flags);
++	local_lock_irqsave(pa_lock, flags);
+ 	if (zone->pageset != &boot_pageset) {
+ 		for_each_online_cpu(cpu) {
+ 			pset = per_cpu_ptr(zone->pageset, cpu);
+@@ -7172,7 +7236,7 @@ void zone_pcp_reset(struct zone *zone)
+ 		free_percpu(zone->pageset);
+ 		zone->pageset = &boot_pageset;
+ 	}
+-	local_irq_restore(flags);
++	local_unlock_irqrestore(pa_lock, flags);
+ }
+ 
+ #ifdef CONFIG_MEMORY_HOTREMOVE
+diff --git a/mm/slab.h b/mm/slab.h
+index 5969769fbee6..b85c60f6dba8 100644
+--- a/mm/slab.h
++++ b/mm/slab.h
+@@ -415,7 +415,11 @@ static inline void slab_post_alloc_hook(struct kmem_cache *s, gfp_t flags,
+  * The slab lists for all objects.
+  */
+ struct kmem_cache_node {
++#ifdef CONFIG_SLUB
++	raw_spinlock_t list_lock;
++#else
+ 	spinlock_t list_lock;
++#endif
+ 
+ #ifdef CONFIG_SLAB
+ 	struct list_head slabs_partial;	/* partial list first, better asm code */
+diff --git a/mm/slub.c b/mm/slub.c
+index 4dbb109eb8cd..2d10cc519150 100644
+--- a/mm/slub.c
++++ b/mm/slub.c
+@@ -1143,7 +1143,7 @@ static noinline int free_debug_processing(
+ 	unsigned long uninitialized_var(flags);
+ 	int ret = 0;
+ 
+-	spin_lock_irqsave(&n->list_lock, flags);
++	raw_spin_lock_irqsave(&n->list_lock, flags);
+ 	slab_lock(page);
+ 
+ 	if (s->flags & SLAB_CONSISTENCY_CHECKS) {
+@@ -1178,7 +1178,7 @@ static noinline int free_debug_processing(
+ 			 bulk_cnt, cnt);
+ 
+ 	slab_unlock(page);
+-	spin_unlock_irqrestore(&n->list_lock, flags);
++	raw_spin_unlock_irqrestore(&n->list_lock, flags);
+ 	if (!ret)
+ 		slab_fix(s, "Object at 0x%p not freed", object);
+ 	return ret;
+@@ -1306,6 +1306,12 @@ static inline void dec_slabs_node(struct kmem_cache *s, int node,
+ 
+ #endif /* CONFIG_SLUB_DEBUG */
+ 
++struct slub_free_list {
++	raw_spinlock_t		lock;
++	struct list_head	list;
++};
++static DEFINE_PER_CPU(struct slub_free_list, slub_free_list);
++
+ /*
+  * Hooks for other subsystems that check memory allocations. In a typical
+  * production configuration these hooks all should produce no code at all.
+@@ -1412,10 +1418,17 @@ static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node)
+ 	gfp_t alloc_gfp;
+ 	void *start, *p;
+ 	int idx, order;
++	bool enableirqs = false;
+ 
+ 	flags &= gfp_allowed_mask;
+ 
+ 	if (gfpflags_allow_blocking(flags))
++		enableirqs = true;
++#ifdef CONFIG_PREEMPT_RT_FULL
++	if (system_state == SYSTEM_RUNNING)
++		enableirqs = true;
++#endif
++	if (enableirqs)
+ 		local_irq_enable();
+ 
+ 	flags |= s->allocflags;
+@@ -1486,7 +1499,7 @@ static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node)
+ 	page->frozen = 1;
+ 
+ out:
+-	if (gfpflags_allow_blocking(flags))
++	if (enableirqs)
+ 		local_irq_disable();
+ 	if (!page)
+ 		return NULL;
+@@ -1543,6 +1556,16 @@ static void __free_slab(struct kmem_cache *s, struct page *page)
+ 	__free_pages(page, order);
+ }
+ 
++static void free_delayed(struct list_head *h)
++{
++	while(!list_empty(h)) {
++		struct page *page = list_first_entry(h, struct page, lru);
++
++		list_del(&page->lru);
++		__free_slab(page->slab_cache, page);
++	}
++}
++
+ #define need_reserve_slab_rcu						\
+ 	(sizeof(((struct page *)NULL)->lru) < sizeof(struct rcu_head))
+ 
+@@ -1574,6 +1597,12 @@ static void free_slab(struct kmem_cache *s, struct page *page)
+ 		}
+ 
+ 		call_rcu(head, rcu_free_slab);
++	} else if (irqs_disabled()) {
++		struct slub_free_list *f = this_cpu_ptr(&slub_free_list);
++
++		raw_spin_lock(&f->lock);
++		list_add(&page->lru, &f->list);
++		raw_spin_unlock(&f->lock);
+ 	} else
+ 		__free_slab(s, page);
+ }
+@@ -1681,7 +1710,7 @@ static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n,
+ 	if (!n || !n->nr_partial)
+ 		return NULL;
+ 
+-	spin_lock(&n->list_lock);
++	raw_spin_lock(&n->list_lock);
+ 	list_for_each_entry_safe(page, page2, &n->partial, lru) {
+ 		void *t;
+ 
+@@ -1706,7 +1735,7 @@ static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n,
+ 			break;
+ 
+ 	}
+-	spin_unlock(&n->list_lock);
++	raw_spin_unlock(&n->list_lock);
+ 	return object;
+ }
+ 
+@@ -1952,7 +1981,7 @@ static void deactivate_slab(struct kmem_cache *s, struct page *page,
+ 			 * that acquire_slab() will see a slab page that
+ 			 * is frozen
+ 			 */
+-			spin_lock(&n->list_lock);
++			raw_spin_lock(&n->list_lock);
+ 		}
+ 	} else {
+ 		m = M_FULL;
+@@ -1963,7 +1992,7 @@ static void deactivate_slab(struct kmem_cache *s, struct page *page,
+ 			 * slabs from diagnostic functions will not see
+ 			 * any frozen slabs.
+ 			 */
+-			spin_lock(&n->list_lock);
++			raw_spin_lock(&n->list_lock);
+ 		}
+ 	}
+ 
+@@ -1998,7 +2027,7 @@ static void deactivate_slab(struct kmem_cache *s, struct page *page,
+ 		goto redo;
+ 
+ 	if (lock)
+-		spin_unlock(&n->list_lock);
++		raw_spin_unlock(&n->list_lock);
+ 
+ 	if (m == M_FREE) {
+ 		stat(s, DEACTIVATE_EMPTY);
+@@ -2030,10 +2059,10 @@ static void unfreeze_partials(struct kmem_cache *s,
+ 		n2 = get_node(s, page_to_nid(page));
+ 		if (n != n2) {
+ 			if (n)
+-				spin_unlock(&n->list_lock);
++				raw_spin_unlock(&n->list_lock);
+ 
+ 			n = n2;
+-			spin_lock(&n->list_lock);
++			raw_spin_lock(&n->list_lock);
+ 		}
+ 
+ 		do {
+@@ -2062,7 +2091,7 @@ static void unfreeze_partials(struct kmem_cache *s,
+ 	}
+ 
+ 	if (n)
+-		spin_unlock(&n->list_lock);
++		raw_spin_unlock(&n->list_lock);
+ 
+ 	while (discard_page) {
+ 		page = discard_page;
+@@ -2101,14 +2130,21 @@ static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain)
+ 			pobjects = oldpage->pobjects;
+ 			pages = oldpage->pages;
+ 			if (drain && pobjects > s->cpu_partial) {
++				struct slub_free_list *f;
+ 				unsigned long flags;
++				LIST_HEAD(tofree);
+ 				/*
+ 				 * partial array is full. Move the existing
+ 				 * set to the per node partial list.
+ 				 */
+ 				local_irq_save(flags);
+ 				unfreeze_partials(s, this_cpu_ptr(s->cpu_slab));
++				f = this_cpu_ptr(&slub_free_list);
++				raw_spin_lock(&f->lock);
++				list_splice_init(&f->list, &tofree);
++				raw_spin_unlock(&f->lock);
+ 				local_irq_restore(flags);
++				free_delayed(&tofree);
+ 				oldpage = NULL;
+ 				pobjects = 0;
+ 				pages = 0;
+@@ -2180,7 +2216,22 @@ static bool has_cpu_slab(int cpu, void *info)
+ 
+ static void flush_all(struct kmem_cache *s)
+ {
++	LIST_HEAD(tofree);
++	int cpu;
++
+ 	on_each_cpu_cond(has_cpu_slab, flush_cpu_slab, s, 1, GFP_ATOMIC);
++	for_each_online_cpu(cpu) {
++		struct slub_free_list *f;
++
++		if (!has_cpu_slab(cpu, s))
++			continue;
++
++		f = &per_cpu(slub_free_list, cpu);
++		raw_spin_lock_irq(&f->lock);
++		list_splice_init(&f->list, &tofree);
++		raw_spin_unlock_irq(&f->lock);
++		free_delayed(&tofree);
++	}
+ }
+ 
+ /*
+@@ -2216,10 +2267,10 @@ static unsigned long count_partial(struct kmem_cache_node *n,
+ 	unsigned long x = 0;
+ 	struct page *page;
+ 
+-	spin_lock_irqsave(&n->list_lock, flags);
++	raw_spin_lock_irqsave(&n->list_lock, flags);
+ 	list_for_each_entry(page, &n->partial, lru)
+ 		x += get_count(page);
+-	spin_unlock_irqrestore(&n->list_lock, flags);
++	raw_spin_unlock_irqrestore(&n->list_lock, flags);
+ 	return x;
+ }
+ #endif /* CONFIG_SLUB_DEBUG || CONFIG_SYSFS */
+@@ -2357,8 +2408,10 @@ static inline void *get_freelist(struct kmem_cache *s, struct page *page)
+  * already disabled (which is the case for bulk allocation).
+  */
+ static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
+-			  unsigned long addr, struct kmem_cache_cpu *c)
++			  unsigned long addr, struct kmem_cache_cpu *c,
++			  struct list_head *to_free)
+ {
++	struct slub_free_list *f;
+ 	void *freelist;
+ 	struct page *page;
+ 
+@@ -2418,6 +2471,13 @@ static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
+ 	VM_BUG_ON(!c->page->frozen);
+ 	c->freelist = get_freepointer(s, freelist);
+ 	c->tid = next_tid(c->tid);
++
++out:
++	f = this_cpu_ptr(&slub_free_list);
++	raw_spin_lock(&f->lock);
++	list_splice_init(&f->list, to_free);
++	raw_spin_unlock(&f->lock);
++
+ 	return freelist;
+ 
+ new_slab:
+@@ -2449,7 +2509,7 @@ static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
+ 	deactivate_slab(s, page, get_freepointer(s, freelist));
+ 	c->page = NULL;
+ 	c->freelist = NULL;
+-	return freelist;
++	goto out;
+ }
+ 
+ /*
+@@ -2461,6 +2521,7 @@ static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
+ {
+ 	void *p;
+ 	unsigned long flags;
++	LIST_HEAD(tofree);
+ 
+ 	local_irq_save(flags);
+ #ifdef CONFIG_PREEMPT
+@@ -2472,8 +2533,9 @@ static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
+ 	c = this_cpu_ptr(s->cpu_slab);
+ #endif
+ 
+-	p = ___slab_alloc(s, gfpflags, node, addr, c);
++	p = ___slab_alloc(s, gfpflags, node, addr, c, &tofree);
+ 	local_irq_restore(flags);
++	free_delayed(&tofree);
+ 	return p;
+ }
+ 
+@@ -2659,7 +2721,7 @@ static void __slab_free(struct kmem_cache *s, struct page *page,
+ 
+ 	do {
+ 		if (unlikely(n)) {
+-			spin_unlock_irqrestore(&n->list_lock, flags);
++			raw_spin_unlock_irqrestore(&n->list_lock, flags);
+ 			n = NULL;
+ 		}
+ 		prior = page->freelist;
+@@ -2691,7 +2753,7 @@ static void __slab_free(struct kmem_cache *s, struct page *page,
+ 				 * Otherwise the list_lock will synchronize with
+ 				 * other processors updating the list of slabs.
+ 				 */
+-				spin_lock_irqsave(&n->list_lock, flags);
++				raw_spin_lock_irqsave(&n->list_lock, flags);
+ 
+ 			}
+ 		}
+@@ -2733,7 +2795,7 @@ static void __slab_free(struct kmem_cache *s, struct page *page,
+ 		add_partial(n, page, DEACTIVATE_TO_TAIL);
+ 		stat(s, FREE_ADD_PARTIAL);
+ 	}
+-	spin_unlock_irqrestore(&n->list_lock, flags);
++	raw_spin_unlock_irqrestore(&n->list_lock, flags);
+ 	return;
+ 
+ slab_empty:
+@@ -2748,7 +2810,7 @@ static void __slab_free(struct kmem_cache *s, struct page *page,
+ 		remove_full(s, n, page);
+ 	}
+ 
+-	spin_unlock_irqrestore(&n->list_lock, flags);
++	raw_spin_unlock_irqrestore(&n->list_lock, flags);
+ 	stat(s, FREE_SLAB);
+ 	discard_slab(s, page);
+ }
+@@ -2935,6 +2997,7 @@ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size,
+ 			  void **p)
+ {
+ 	struct kmem_cache_cpu *c;
++	LIST_HEAD(to_free);
+ 	int i;
+ 
+ 	/* memcg and kmem_cache debug support */
+@@ -2958,7 +3021,7 @@ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size,
+ 			 * of re-populating per CPU c->freelist
+ 			 */
+ 			p[i] = ___slab_alloc(s, flags, NUMA_NO_NODE,
+-					    _RET_IP_, c);
++					    _RET_IP_, c, &to_free);
+ 			if (unlikely(!p[i]))
+ 				goto error;
+ 
+@@ -2970,6 +3033,7 @@ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size,
+ 	}
+ 	c->tid = next_tid(c->tid);
+ 	local_irq_enable();
++	free_delayed(&to_free);
+ 
+ 	/* Clear memory outside IRQ disabled fastpath loop */
+ 	if (unlikely(flags & __GFP_ZERO)) {
+@@ -3117,7 +3181,7 @@ static void
+ init_kmem_cache_node(struct kmem_cache_node *n)
+ {
+ 	n->nr_partial = 0;
+-	spin_lock_init(&n->list_lock);
++	raw_spin_lock_init(&n->list_lock);
+ 	INIT_LIST_HEAD(&n->partial);
+ #ifdef CONFIG_SLUB_DEBUG
+ 	atomic_long_set(&n->nr_slabs, 0);
+@@ -3450,6 +3514,10 @@ static void list_slab_objects(struct kmem_cache *s, struct page *page,
+ 							const char *text)
+ {
+ #ifdef CONFIG_SLUB_DEBUG
++#ifdef CONFIG_PREEMPT_RT_BASE
++	/* XXX move out of irq-off section */
++	slab_err(s, page, text, s->name);
++#else
+ 	void *addr = page_address(page);
+ 	void *p;
+ 	unsigned long *map = kzalloc(BITS_TO_LONGS(page->objects) *
+@@ -3470,6 +3538,7 @@ static void list_slab_objects(struct kmem_cache *s, struct page *page,
+ 	slab_unlock(page);
+ 	kfree(map);
+ #endif
++#endif
+ }
+ 
+ /*
+@@ -3482,7 +3551,7 @@ static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n)
+ 	struct page *page, *h;
+ 
+ 	BUG_ON(irqs_disabled());
+-	spin_lock_irq(&n->list_lock);
++	raw_spin_lock_irq(&n->list_lock);
+ 	list_for_each_entry_safe(page, h, &n->partial, lru) {
+ 		if (!page->inuse) {
+ 			remove_partial(n, page);
+@@ -3492,7 +3561,7 @@ static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n)
+ 			"Objects remaining in %s on __kmem_cache_shutdown()");
+ 		}
+ 	}
+-	spin_unlock_irq(&n->list_lock);
++	raw_spin_unlock_irq(&n->list_lock);
+ }
+ 
+ /*
+@@ -3706,7 +3775,7 @@ int __kmem_cache_shrink(struct kmem_cache *s, bool deactivate)
+ 		for (i = 0; i < SHRINK_PROMOTE_MAX; i++)
+ 			INIT_LIST_HEAD(promote + i);
+ 
+-		spin_lock_irqsave(&n->list_lock, flags);
++		raw_spin_lock_irqsave(&n->list_lock, flags);
+ 
+ 		/*
+ 		 * Build lists of slabs to discard or promote.
+@@ -3737,7 +3806,7 @@ int __kmem_cache_shrink(struct kmem_cache *s, bool deactivate)
+ 		for (i = SHRINK_PROMOTE_MAX - 1; i >= 0; i--)
+ 			list_splice(promote + i, &n->partial);
+ 
+-		spin_unlock_irqrestore(&n->list_lock, flags);
++		raw_spin_unlock_irqrestore(&n->list_lock, flags);
+ 
+ 		/* Release empty slabs */
+ 		list_for_each_entry_safe(page, t, &discard, lru)
+@@ -3913,6 +3982,12 @@ void __init kmem_cache_init(void)
+ {
+ 	static __initdata struct kmem_cache boot_kmem_cache,
+ 		boot_kmem_cache_node;
++	int cpu;
++
++	for_each_possible_cpu(cpu) {
++		raw_spin_lock_init(&per_cpu(slub_free_list, cpu).lock);
++		INIT_LIST_HEAD(&per_cpu(slub_free_list, cpu).list);
++	}
+ 
+ 	if (debug_guardpage_minorder())
+ 		slub_max_order = 0;
+@@ -4156,7 +4231,7 @@ static int validate_slab_node(struct kmem_cache *s,
+ 	struct page *page;
+ 	unsigned long flags;
+ 
+-	spin_lock_irqsave(&n->list_lock, flags);
++	raw_spin_lock_irqsave(&n->list_lock, flags);
+ 
+ 	list_for_each_entry(page, &n->partial, lru) {
+ 		validate_slab_slab(s, page, map);
+@@ -4178,7 +4253,7 @@ static int validate_slab_node(struct kmem_cache *s,
+ 		       s->name, count, atomic_long_read(&n->nr_slabs));
+ 
+ out:
+-	spin_unlock_irqrestore(&n->list_lock, flags);
++	raw_spin_unlock_irqrestore(&n->list_lock, flags);
+ 	return count;
+ }
+ 
+@@ -4366,12 +4441,12 @@ static int list_locations(struct kmem_cache *s, char *buf,
+ 		if (!atomic_long_read(&n->nr_slabs))
+ 			continue;
+ 
+-		spin_lock_irqsave(&n->list_lock, flags);
++		raw_spin_lock_irqsave(&n->list_lock, flags);
+ 		list_for_each_entry(page, &n->partial, lru)
+ 			process_slab(&t, s, page, alloc, map);
+ 		list_for_each_entry(page, &n->full, lru)
+ 			process_slab(&t, s, page, alloc, map);
+-		spin_unlock_irqrestore(&n->list_lock, flags);
++		raw_spin_unlock_irqrestore(&n->list_lock, flags);
+ 	}
+ 
+ 	for (i = 0; i < t.count; i++) {
+diff --git a/mm/swap.c b/mm/swap.c
+index 03aacbcb013f..d3558eb2f685 100644
+--- a/mm/swap.c
++++ b/mm/swap.c
+@@ -32,6 +32,7 @@
+ #include <linux/memcontrol.h>
+ #include <linux/gfp.h>
+ #include <linux/uio.h>
++#include <linux/locallock.h>
+ #include <linux/hugetlb.h>
+ #include <linux/page_idle.h>
+ 
+@@ -48,6 +49,9 @@ static DEFINE_PER_CPU(struct pagevec, lru_rotate_pvecs);
+ static DEFINE_PER_CPU(struct pagevec, lru_deactivate_file_pvecs);
+ static DEFINE_PER_CPU(struct pagevec, lru_deactivate_pvecs);
+ 
++static DEFINE_LOCAL_IRQ_LOCK(rotate_lock);
++DEFINE_LOCAL_IRQ_LOCK(swapvec_lock);
++
+ /*
+  * This path almost never happens for VM activity - pages are normally
+  * freed via pagevecs.  But it gets used by networking.
+@@ -237,11 +241,11 @@ void rotate_reclaimable_page(struct page *page)
+ 		unsigned long flags;
+ 
+ 		get_page(page);
+-		local_irq_save(flags);
++		local_lock_irqsave(rotate_lock, flags);
+ 		pvec = this_cpu_ptr(&lru_rotate_pvecs);
+ 		if (!pagevec_add(pvec, page))
+ 			pagevec_move_tail(pvec);
+-		local_irq_restore(flags);
++		local_unlock_irqrestore(rotate_lock, flags);
+ 	}
+ }
+ 
+@@ -292,12 +296,13 @@ static bool need_activate_page_drain(int cpu)
+ void activate_page(struct page *page)
+ {
+ 	if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) {
+-		struct pagevec *pvec = &get_cpu_var(activate_page_pvecs);
++		struct pagevec *pvec = &get_locked_var(swapvec_lock,
++						       activate_page_pvecs);
+ 
+ 		get_page(page);
+ 		if (!pagevec_add(pvec, page))
+ 			pagevec_lru_move_fn(pvec, __activate_page, NULL);
+-		put_cpu_var(activate_page_pvecs);
++		put_locked_var(swapvec_lock, activate_page_pvecs);
+ 	}
+ }
+ 
+@@ -323,7 +328,7 @@ void activate_page(struct page *page)
+ 
+ static void __lru_cache_activate_page(struct page *page)
+ {
+-	struct pagevec *pvec = &get_cpu_var(lru_add_pvec);
++	struct pagevec *pvec = &get_locked_var(swapvec_lock, lru_add_pvec);
+ 	int i;
+ 
+ 	/*
+@@ -345,7 +350,7 @@ static void __lru_cache_activate_page(struct page *page)
+ 		}
+ 	}
+ 
+-	put_cpu_var(lru_add_pvec);
++	put_locked_var(swapvec_lock, lru_add_pvec);
+ }
+ 
+ /*
+@@ -387,13 +392,13 @@ EXPORT_SYMBOL(mark_page_accessed);
+ 
+ static void __lru_cache_add(struct page *page)
+ {
+-	struct pagevec *pvec = &get_cpu_var(lru_add_pvec);
++	struct pagevec *pvec = &get_locked_var(swapvec_lock, lru_add_pvec);
+ 
+ 	get_page(page);
+ 	if (!pagevec_space(pvec))
+ 		__pagevec_lru_add(pvec);
+ 	pagevec_add(pvec, page);
+-	put_cpu_var(lru_add_pvec);
++	put_locked_var(swapvec_lock, lru_add_pvec);
+ }
+ 
+ /**
+@@ -591,9 +596,15 @@ void lru_add_drain_cpu(int cpu)
+ 		unsigned long flags;
+ 
+ 		/* No harm done if a racing interrupt already did this */
+-		local_irq_save(flags);
++#ifdef CONFIG_PREEMPT_RT_BASE
++		local_lock_irqsave_on(rotate_lock, flags, cpu);
+ 		pagevec_move_tail(pvec);
+-		local_irq_restore(flags);
++		local_unlock_irqrestore_on(rotate_lock, flags, cpu);
++#else
++		local_lock_irqsave(rotate_lock, flags);
++		pagevec_move_tail(pvec);
++		local_unlock_irqrestore(rotate_lock, flags);
++#endif
+ 	}
+ 
+ 	pvec = &per_cpu(lru_deactivate_file_pvecs, cpu);
+@@ -625,11 +636,12 @@ void deactivate_file_page(struct page *page)
+ 		return;
+ 
+ 	if (likely(get_page_unless_zero(page))) {
+-		struct pagevec *pvec = &get_cpu_var(lru_deactivate_file_pvecs);
++		struct pagevec *pvec = &get_locked_var(swapvec_lock,
++						       lru_deactivate_file_pvecs);
+ 
+ 		if (!pagevec_add(pvec, page))
+ 			pagevec_lru_move_fn(pvec, lru_deactivate_file_fn, NULL);
+-		put_cpu_var(lru_deactivate_file_pvecs);
++		put_locked_var(swapvec_lock, lru_deactivate_file_pvecs);
+ 	}
+ }
+ 
+@@ -644,27 +656,48 @@ void deactivate_file_page(struct page *page)
+ void deactivate_page(struct page *page)
+ {
+ 	if (PageLRU(page) && PageActive(page) && !PageUnevictable(page)) {
+-		struct pagevec *pvec = &get_cpu_var(lru_deactivate_pvecs);
++		struct pagevec *pvec = &get_locked_var(swapvec_lock,
++						       lru_deactivate_pvecs);
+ 
+ 		get_page(page);
+ 		if (!pagevec_add(pvec, page))
+ 			pagevec_lru_move_fn(pvec, lru_deactivate_fn, NULL);
+-		put_cpu_var(lru_deactivate_pvecs);
++		put_locked_var(swapvec_lock, lru_deactivate_pvecs);
+ 	}
+ }
+ 
+ void lru_add_drain(void)
+ {
+-	lru_add_drain_cpu(get_cpu());
+-	put_cpu();
++	lru_add_drain_cpu(local_lock_cpu(swapvec_lock));
++	local_unlock_cpu(swapvec_lock);
+ }
+ 
++
++#ifdef CONFIG_PREEMPT_RT_BASE
++static inline void remote_lru_add_drain(int cpu, struct cpumask *has_work)
++{
++	local_lock_on(swapvec_lock, cpu);
++	lru_add_drain_cpu(cpu);
++	local_unlock_on(swapvec_lock, cpu);
++}
++
++#else
++
+ static void lru_add_drain_per_cpu(struct work_struct *dummy)
+ {
+ 	lru_add_drain();
+ }
+ 
+ static DEFINE_PER_CPU(struct work_struct, lru_add_drain_work);
++static inline void remote_lru_add_drain(int cpu, struct cpumask *has_work)
++{
++	struct work_struct *work = &per_cpu(lru_add_drain_work, cpu);
++
++	INIT_WORK(work, lru_add_drain_per_cpu);
++	schedule_work_on(cpu, work);
++	cpumask_set_cpu(cpu, has_work);
++}
++#endif
+ 
+ void lru_add_drain_all(void)
+ {
+@@ -677,21 +710,18 @@ void lru_add_drain_all(void)
+ 	cpumask_clear(&has_work);
+ 
+ 	for_each_online_cpu(cpu) {
+-		struct work_struct *work = &per_cpu(lru_add_drain_work, cpu);
+-
+ 		if (pagevec_count(&per_cpu(lru_add_pvec, cpu)) ||
+ 		    pagevec_count(&per_cpu(lru_rotate_pvecs, cpu)) ||
+ 		    pagevec_count(&per_cpu(lru_deactivate_file_pvecs, cpu)) ||
+ 		    pagevec_count(&per_cpu(lru_deactivate_pvecs, cpu)) ||
+-		    need_activate_page_drain(cpu)) {
+-			INIT_WORK(work, lru_add_drain_per_cpu);
+-			schedule_work_on(cpu, work);
+-			cpumask_set_cpu(cpu, &has_work);
+-		}
++		    need_activate_page_drain(cpu))
++			remote_lru_add_drain(cpu, &has_work);
+ 	}
+ 
++#ifndef CONFIG_PREEMPT_RT_BASE
+ 	for_each_cpu(cpu, &has_work)
+ 		flush_work(&per_cpu(lru_add_drain_work, cpu));
++#endif
+ 
+ 	put_online_cpus();
+ 	mutex_unlock(&lock);
+diff --git a/mm/truncate.c b/mm/truncate.c
+index b00272810871..dcc445a87dfe 100644
+--- a/mm/truncate.c
++++ b/mm/truncate.c
+@@ -63,9 +63,12 @@ static void clear_exceptional_entry(struct address_space *mapping,
+ 		 * protected by mapping->tree_lock.
+ 		 */
+ 		if (!workingset_node_shadows(node) &&
+-		    !list_empty(&node->private_list))
+-			list_lru_del(&workingset_shadow_nodes,
++		    !list_empty(&node->private_list)) {
++			local_lock(workingset_shadow_lock);
++			list_lru_del(&__workingset_shadow_nodes,
+ 					&node->private_list);
++			local_unlock(workingset_shadow_lock);
++		}
+ 		__radix_tree_delete_node(&mapping->page_tree, node);
+ 	}
+ unlock:
+diff --git a/mm/vmalloc.c b/mm/vmalloc.c
+index ae7d20b447ff..b7d6f721c2a7 100644
+--- a/mm/vmalloc.c
++++ b/mm/vmalloc.c
+@@ -819,7 +819,7 @@ static void *new_vmap_block(unsigned int order, gfp_t gfp_mask)
+ 	struct vmap_block *vb;
+ 	struct vmap_area *va;
+ 	unsigned long vb_idx;
+-	int node, err;
++	int node, err, cpu;
+ 	void *vaddr;
+ 
+ 	node = numa_node_id();
+@@ -862,11 +862,12 @@ static void *new_vmap_block(unsigned int order, gfp_t gfp_mask)
+ 	BUG_ON(err);
+ 	radix_tree_preload_end();
+ 
+-	vbq = &get_cpu_var(vmap_block_queue);
++	cpu = get_cpu_light();
++	vbq = this_cpu_ptr(&vmap_block_queue);
+ 	spin_lock(&vbq->lock);
+ 	list_add_tail_rcu(&vb->free_list, &vbq->free);
+ 	spin_unlock(&vbq->lock);
+-	put_cpu_var(vmap_block_queue);
++	put_cpu_light();
+ 
+ 	return vaddr;
+ }
+@@ -935,6 +936,7 @@ static void *vb_alloc(unsigned long size, gfp_t gfp_mask)
+ 	struct vmap_block *vb;
+ 	void *vaddr = NULL;
+ 	unsigned int order;
++	int cpu;
+ 
+ 	BUG_ON(offset_in_page(size));
+ 	BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC);
+@@ -949,7 +951,8 @@ static void *vb_alloc(unsigned long size, gfp_t gfp_mask)
+ 	order = get_order(size);
+ 
+ 	rcu_read_lock();
+-	vbq = &get_cpu_var(vmap_block_queue);
++	cpu = get_cpu_light();
++	vbq = this_cpu_ptr(&vmap_block_queue);
+ 	list_for_each_entry_rcu(vb, &vbq->free, free_list) {
+ 		unsigned long pages_off;
+ 
+@@ -972,7 +975,7 @@ static void *vb_alloc(unsigned long size, gfp_t gfp_mask)
+ 		break;
+ 	}
+ 
+-	put_cpu_var(vmap_block_queue);
++	put_cpu_light();
+ 	rcu_read_unlock();
+ 
+ 	/* Allocate new block if nothing was found */
+diff --git a/mm/vmstat.c b/mm/vmstat.c
+index 5e4300482897..1ae743192c66 100644
+--- a/mm/vmstat.c
++++ b/mm/vmstat.c
+@@ -226,6 +226,7 @@ void __mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
+ 	long x;
+ 	long t;
+ 
++	preempt_disable_rt();
+ 	x = delta + __this_cpu_read(*p);
+ 
+ 	t = __this_cpu_read(pcp->stat_threshold);
+@@ -235,6 +236,7 @@ void __mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
+ 		x = 0;
+ 	}
+ 	__this_cpu_write(*p, x);
++	preempt_enable_rt();
+ }
+ EXPORT_SYMBOL(__mod_zone_page_state);
+ 
+@@ -267,6 +269,7 @@ void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
+ 	s8 __percpu *p = pcp->vm_stat_diff + item;
+ 	s8 v, t;
+ 
++	preempt_disable_rt();
+ 	v = __this_cpu_inc_return(*p);
+ 	t = __this_cpu_read(pcp->stat_threshold);
+ 	if (unlikely(v > t)) {
+@@ -275,6 +278,7 @@ void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
+ 		zone_page_state_add(v + overstep, zone, item);
+ 		__this_cpu_write(*p, -overstep);
+ 	}
++	preempt_enable_rt();
+ }
+ 
+ void __inc_zone_page_state(struct page *page, enum zone_stat_item item)
+@@ -289,6 +293,7 @@ void __dec_zone_state(struct zone *zone, enum zone_stat_item item)
+ 	s8 __percpu *p = pcp->vm_stat_diff + item;
+ 	s8 v, t;
+ 
++	preempt_disable_rt();
+ 	v = __this_cpu_dec_return(*p);
+ 	t = __this_cpu_read(pcp->stat_threshold);
+ 	if (unlikely(v < - t)) {
+@@ -297,6 +302,7 @@ void __dec_zone_state(struct zone *zone, enum zone_stat_item item)
+ 		zone_page_state_add(v - overstep, zone, item);
+ 		__this_cpu_write(*p, overstep);
+ 	}
++	preempt_enable_rt();
+ }
+ 
+ void __dec_zone_page_state(struct page *page, enum zone_stat_item item)
+diff --git a/mm/workingset.c b/mm/workingset.c
+index 8a75f8d2916a..00a38f9f0f37 100644
+--- a/mm/workingset.c
++++ b/mm/workingset.c
+@@ -335,7 +335,8 @@ void workingset_activation(struct page *page)
+  * point where they would still be useful.
+  */
+ 
+-struct list_lru workingset_shadow_nodes;
++struct list_lru __workingset_shadow_nodes;
++DEFINE_LOCAL_IRQ_LOCK(workingset_shadow_lock);
+ 
+ static unsigned long count_shadow_nodes(struct shrinker *shrinker,
+ 					struct shrink_control *sc)
+@@ -345,9 +346,9 @@ static unsigned long count_shadow_nodes(struct shrinker *shrinker,
+ 	unsigned long pages;
+ 
+ 	/* list_lru lock nests inside IRQ-safe mapping->tree_lock */
+-	local_irq_disable();
+-	shadow_nodes = list_lru_shrink_count(&workingset_shadow_nodes, sc);
+-	local_irq_enable();
++	local_lock_irq(workingset_shadow_lock);
++	shadow_nodes = list_lru_shrink_count(&__workingset_shadow_nodes, sc);
++	local_unlock_irq(workingset_shadow_lock);
+ 
+ 	if (memcg_kmem_enabled())
+ 		pages = mem_cgroup_node_nr_lru_pages(sc->memcg, sc->nid,
+@@ -440,9 +441,9 @@ static enum lru_status shadow_lru_isolate(struct list_head *item,
+ 	spin_unlock(&mapping->tree_lock);
+ 	ret = LRU_REMOVED_RETRY;
+ out:
+-	local_irq_enable();
++	local_unlock_irq(workingset_shadow_lock);
+ 	cond_resched();
+-	local_irq_disable();
++	local_lock_irq(workingset_shadow_lock);
+ 	spin_lock(lru_lock);
+ 	return ret;
+ }
+@@ -453,10 +454,10 @@ static unsigned long scan_shadow_nodes(struct shrinker *shrinker,
+ 	unsigned long ret;
+ 
+ 	/* list_lru lock nests inside IRQ-safe mapping->tree_lock */
+-	local_irq_disable();
+-	ret =  list_lru_shrink_walk(&workingset_shadow_nodes, sc,
++	local_lock_irq(workingset_shadow_lock);
++	ret =  list_lru_shrink_walk(&__workingset_shadow_nodes, sc,
+ 				    shadow_lru_isolate, NULL);
+-	local_irq_enable();
++	local_unlock_irq(workingset_shadow_lock);
+ 	return ret;
+ }
+ 
+@@ -494,7 +495,7 @@ static int __init workingset_init(void)
+ 	printk("workingset: timestamp_bits=%d max_order=%d bucket_order=%u\n",
+ 	       timestamp_bits, max_order, bucket_order);
+ 
+-	ret = list_lru_init_key(&workingset_shadow_nodes, &shadow_nodes_key);
++	ret = list_lru_init_key(&__workingset_shadow_nodes, &shadow_nodes_key);
+ 	if (ret)
+ 		goto err;
+ 	ret = register_shrinker(&workingset_shadow_shrinker);
+@@ -502,7 +503,7 @@ static int __init workingset_init(void)
+ 		goto err_list_lru;
+ 	return 0;
+ err_list_lru:
+-	list_lru_destroy(&workingset_shadow_nodes);
++	list_lru_destroy(&__workingset_shadow_nodes);
+ err:
+ 	return ret;
+ }
+diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
+index fe47fbba995a..e46d7bcf562e 100644
+--- a/mm/zsmalloc.c
++++ b/mm/zsmalloc.c
+@@ -1292,7 +1292,7 @@ void *zs_map_object(struct zs_pool *pool, unsigned long handle,
+ 	class = pool->size_class[class_idx];
+ 	off = obj_idx_to_offset(page, obj_idx, class->size);
+ 
+-	area = &get_cpu_var(zs_map_area);
++	area = per_cpu_ptr(&zs_map_area, get_cpu_light());
+ 	area->vm_mm = mm;
+ 	if (off + class->size <= PAGE_SIZE) {
+ 		/* this object is contained entirely within a page */
+@@ -1345,7 +1345,7 @@ void zs_unmap_object(struct zs_pool *pool, unsigned long handle)
+ 
+ 		__zs_unmap_object(area, pages, off, class->size);
+ 	}
+-	put_cpu_var(zs_map_area);
++	put_cpu_light();
+ 	unpin_tag(handle);
+ }
+ EXPORT_SYMBOL_GPL(zs_unmap_object);
+diff --git a/net/core/dev.c b/net/core/dev.c
+index 5c925ac50b95..a8fedf89eb12 100644
+--- a/net/core/dev.c
++++ b/net/core/dev.c
+@@ -188,6 +188,7 @@ static unsigned int napi_gen_id = NR_CPUS;
+ static DEFINE_READ_MOSTLY_HASHTABLE(napi_hash, 8);
+ 
+ static seqcount_t devnet_rename_seq;
++static DEFINE_MUTEX(devnet_rename_mutex);
+ 
+ static inline void dev_base_seq_inc(struct net *net)
+ {
+@@ -209,14 +210,14 @@ static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex)
+ static inline void rps_lock(struct softnet_data *sd)
+ {
+ #ifdef CONFIG_RPS
+-	spin_lock(&sd->input_pkt_queue.lock);
++	raw_spin_lock(&sd->input_pkt_queue.raw_lock);
+ #endif
+ }
+ 
+ static inline void rps_unlock(struct softnet_data *sd)
+ {
+ #ifdef CONFIG_RPS
+-	spin_unlock(&sd->input_pkt_queue.lock);
++	raw_spin_unlock(&sd->input_pkt_queue.raw_lock);
+ #endif
+ }
+ 
+@@ -886,7 +887,8 @@ int netdev_get_name(struct net *net, char *name, int ifindex)
+ 	strcpy(name, dev->name);
+ 	rcu_read_unlock();
+ 	if (read_seqcount_retry(&devnet_rename_seq, seq)) {
+-		cond_resched();
++		mutex_lock(&devnet_rename_mutex);
++		mutex_unlock(&devnet_rename_mutex);
+ 		goto retry;
+ 	}
+ 
+@@ -1155,20 +1157,17 @@ int dev_change_name(struct net_device *dev, const char *newname)
+ 	if (dev->flags & IFF_UP)
+ 		return -EBUSY;
+ 
+-	write_seqcount_begin(&devnet_rename_seq);
++	mutex_lock(&devnet_rename_mutex);
++	__raw_write_seqcount_begin(&devnet_rename_seq);
+ 
+-	if (strncmp(newname, dev->name, IFNAMSIZ) == 0) {
+-		write_seqcount_end(&devnet_rename_seq);
+-		return 0;
+-	}
++	if (strncmp(newname, dev->name, IFNAMSIZ) == 0)
++		goto outunlock;
+ 
+ 	memcpy(oldname, dev->name, IFNAMSIZ);
+ 
+ 	err = dev_get_valid_name(net, dev, newname);
+-	if (err < 0) {
+-		write_seqcount_end(&devnet_rename_seq);
+-		return err;
+-	}
++	if (err < 0)
++		goto outunlock;
+ 
+ 	if (oldname[0] && !strchr(oldname, '%'))
+ 		netdev_info(dev, "renamed from %s\n", oldname);
+@@ -1181,11 +1180,12 @@ int dev_change_name(struct net_device *dev, const char *newname)
+ 	if (ret) {
+ 		memcpy(dev->name, oldname, IFNAMSIZ);
+ 		dev->name_assign_type = old_assign_type;
+-		write_seqcount_end(&devnet_rename_seq);
+-		return ret;
++		err = ret;
++		goto outunlock;
+ 	}
+ 
+-	write_seqcount_end(&devnet_rename_seq);
++	__raw_write_seqcount_end(&devnet_rename_seq);
++	mutex_unlock(&devnet_rename_mutex);
+ 
+ 	netdev_adjacent_rename_links(dev, oldname);
+ 
+@@ -1206,7 +1206,8 @@ int dev_change_name(struct net_device *dev, const char *newname)
+ 		/* err >= 0 after dev_alloc_name() or stores the first errno */
+ 		if (err >= 0) {
+ 			err = ret;
+-			write_seqcount_begin(&devnet_rename_seq);
++			mutex_lock(&devnet_rename_mutex);
++			__raw_write_seqcount_begin(&devnet_rename_seq);
+ 			memcpy(dev->name, oldname, IFNAMSIZ);
+ 			memcpy(oldname, newname, IFNAMSIZ);
+ 			dev->name_assign_type = old_assign_type;
+@@ -1219,6 +1220,11 @@ int dev_change_name(struct net_device *dev, const char *newname)
+ 	}
+ 
+ 	return err;
++
++outunlock:
++	__raw_write_seqcount_end(&devnet_rename_seq);
++	mutex_unlock(&devnet_rename_mutex);
++	return err;
+ }
+ 
+ /**
+@@ -2264,6 +2270,7 @@ static inline void __netif_reschedule(struct Qdisc *q)
+ 	sd->output_queue_tailp = &q->next_sched;
+ 	raise_softirq_irqoff(NET_TX_SOFTIRQ);
+ 	local_irq_restore(flags);
++	preempt_check_resched_rt();
+ }
+ 
+ void __netif_schedule(struct Qdisc *q)
+@@ -2345,6 +2352,7 @@ void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason)
+ 	__this_cpu_write(softnet_data.completion_queue, skb);
+ 	raise_softirq_irqoff(NET_TX_SOFTIRQ);
+ 	local_irq_restore(flags);
++	preempt_check_resched_rt();
+ }
+ EXPORT_SYMBOL(__dev_kfree_skb_irq);
+ 
+@@ -3035,7 +3043,11 @@ static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
+ 	 * This permits __QDISC___STATE_RUNNING owner to get the lock more
+ 	 * often and dequeue packets faster.
+ 	 */
++#ifdef CONFIG_PREEMPT_RT_FULL
++	contended = true;
++#else
+ 	contended = qdisc_is_running(q);
++#endif
+ 	if (unlikely(contended))
+ 		spin_lock(&q->busylock);
+ 
+@@ -3096,9 +3108,44 @@ static void skb_update_prio(struct sk_buff *skb)
+ #define skb_update_prio(skb)
+ #endif
+ 
++#ifdef CONFIG_PREEMPT_RT_FULL
++
++static inline int xmit_rec_read(void)
++{
++       return current->xmit_recursion;
++}
++
++static inline void xmit_rec_inc(void)
++{
++       current->xmit_recursion++;
++}
++
++static inline void xmit_rec_dec(void)
++{
++       current->xmit_recursion--;
++}
++
++#else
++
+ DEFINE_PER_CPU(int, xmit_recursion);
+ EXPORT_SYMBOL(xmit_recursion);
+ 
++static inline int xmit_rec_read(void)
++{
++	return __this_cpu_read(xmit_recursion);
++}
++
++static inline void xmit_rec_inc(void)
++{
++	__this_cpu_inc(xmit_recursion);
++}
++
++static inline void xmit_rec_dec(void)
++{
++	__this_cpu_dec(xmit_recursion);
++}
++#endif
++
+ #define RECURSION_LIMIT 10
+ 
+ /**
+@@ -3344,7 +3391,7 @@ static int __dev_queue_xmit(struct sk_buff *skb, void *accel_priv)
+ 
+ 		if (txq->xmit_lock_owner != cpu) {
+ 
+-			if (__this_cpu_read(xmit_recursion) > RECURSION_LIMIT)
++			if (xmit_rec_read() > RECURSION_LIMIT)
+ 				goto recursion_alert;
+ 
+ 			skb = validate_xmit_skb(skb, dev);
+@@ -3354,9 +3401,9 @@ static int __dev_queue_xmit(struct sk_buff *skb, void *accel_priv)
+ 			HARD_TX_LOCK(dev, txq, cpu);
+ 
+ 			if (!netif_xmit_stopped(txq)) {
+-				__this_cpu_inc(xmit_recursion);
++				xmit_rec_inc();
+ 				skb = dev_hard_start_xmit(skb, dev, txq, &rc);
+-				__this_cpu_dec(xmit_recursion);
++				xmit_rec_dec();
+ 				if (dev_xmit_complete(rc)) {
+ 					HARD_TX_UNLOCK(dev, txq);
+ 					goto out;
+@@ -3730,6 +3777,7 @@ static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
+ 	rps_unlock(sd);
+ 
+ 	local_irq_restore(flags);
++	preempt_check_resched_rt();
+ 
+ 	atomic_long_inc(&skb->dev->rx_dropped);
+ 	kfree_skb(skb);
+@@ -3748,7 +3796,7 @@ static int netif_rx_internal(struct sk_buff *skb)
+ 		struct rps_dev_flow voidflow, *rflow = &voidflow;
+ 		int cpu;
+ 
+-		preempt_disable();
++		migrate_disable();
+ 		rcu_read_lock();
+ 
+ 		cpu = get_rps_cpu(skb->dev, skb, &rflow);
+@@ -3758,13 +3806,13 @@ static int netif_rx_internal(struct sk_buff *skb)
+ 		ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
+ 
+ 		rcu_read_unlock();
+-		preempt_enable();
++		migrate_enable();
+ 	} else
+ #endif
+ 	{
+ 		unsigned int qtail;
+-		ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
+-		put_cpu();
++		ret = enqueue_to_backlog(skb, get_cpu_light(), &qtail);
++		put_cpu_light();
+ 	}
+ 	return ret;
+ }
+@@ -3798,16 +3846,44 @@ int netif_rx_ni(struct sk_buff *skb)
+ 
+ 	trace_netif_rx_ni_entry(skb);
+ 
+-	preempt_disable();
++	local_bh_disable();
+ 	err = netif_rx_internal(skb);
+-	if (local_softirq_pending())
+-		do_softirq();
+-	preempt_enable();
++	local_bh_enable();
+ 
+ 	return err;
+ }
+ EXPORT_SYMBOL(netif_rx_ni);
+ 
++#ifdef CONFIG_PREEMPT_RT_FULL
++/*
++ * RT runs ksoftirqd as a real time thread and the root_lock is a
++ * "sleeping spinlock". If the trylock fails then we can go into an
++ * infinite loop when ksoftirqd preempted the task which actually
++ * holds the lock, because we requeue q and raise NET_TX softirq
++ * causing ksoftirqd to loop forever.
++ *
++ * It's safe to use spin_lock on RT here as softirqs run in thread
++ * context and cannot deadlock against the thread which is holding
++ * root_lock.
++ *
++ * On !RT the trylock might fail, but there we bail out from the
++ * softirq loop after 10 attempts which we can't do on RT. And the
++ * task holding root_lock cannot be preempted, so the only downside of
++ * that trylock is that we need 10 loops to decide that we should have
++ * given up in the first one :)
++ */
++static inline int take_root_lock(spinlock_t *lock)
++{
++	spin_lock(lock);
++	return 1;
++}
++#else
++static inline int take_root_lock(spinlock_t *lock)
++{
++	return spin_trylock(lock);
++}
++#endif
++
+ static void net_tx_action(struct softirq_action *h)
+ {
+ 	struct softnet_data *sd = this_cpu_ptr(&softnet_data);
+@@ -3855,7 +3931,7 @@ static void net_tx_action(struct softirq_action *h)
+ 			head = head->next_sched;
+ 
+ 			root_lock = qdisc_lock(q);
+-			if (spin_trylock(root_lock)) {
++			if (take_root_lock(root_lock)) {
+ 				smp_mb__before_atomic();
+ 				clear_bit(__QDISC_STATE_SCHED,
+ 					  &q->state);
+@@ -4264,7 +4340,7 @@ static void flush_backlog(void *arg)
+ 	skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
+ 		if (skb->dev == dev) {
+ 			__skb_unlink(skb, &sd->input_pkt_queue);
+-			kfree_skb(skb);
++			__skb_queue_tail(&sd->tofree_queue, skb);
+ 			input_queue_head_incr(sd);
+ 		}
+ 	}
+@@ -4273,10 +4349,13 @@ static void flush_backlog(void *arg)
+ 	skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
+ 		if (skb->dev == dev) {
+ 			__skb_unlink(skb, &sd->process_queue);
+-			kfree_skb(skb);
++			__skb_queue_tail(&sd->tofree_queue, skb);
+ 			input_queue_head_incr(sd);
+ 		}
+ 	}
++
++	if (!skb_queue_empty(&sd->tofree_queue))
++		raise_softirq_irqoff(NET_RX_SOFTIRQ);
+ }
+ 
+ static int napi_gro_complete(struct sk_buff *skb)
+@@ -4735,6 +4814,7 @@ static void net_rps_action_and_irq_enable(struct softnet_data *sd)
+ 		sd->rps_ipi_list = NULL;
+ 
+ 		local_irq_enable();
++		preempt_check_resched_rt();
+ 
+ 		/* Send pending IPI's to kick RPS processing on remote cpus. */
+ 		while (remsd) {
+@@ -4748,6 +4828,7 @@ static void net_rps_action_and_irq_enable(struct softnet_data *sd)
+ 	} else
+ #endif
+ 		local_irq_enable();
++	preempt_check_resched_rt();
+ }
+ 
+ static bool sd_has_rps_ipi_waiting(struct softnet_data *sd)
+@@ -4829,6 +4910,7 @@ void __napi_schedule(struct napi_struct *n)
+ 	local_irq_save(flags);
+ 	____napi_schedule(this_cpu_ptr(&softnet_data), n);
+ 	local_irq_restore(flags);
++	preempt_check_resched_rt();
+ }
+ EXPORT_SYMBOL(__napi_schedule);
+ 
+@@ -5169,7 +5251,7 @@ static void net_rx_action(struct softirq_action *h)
+ 	list_splice_tail(&repoll, &list);
+ 	list_splice(&list, &sd->poll_list);
+ 	if (!list_empty(&sd->poll_list))
+-		__raise_softirq_irqoff(NET_RX_SOFTIRQ);
++		__raise_softirq_irqoff_ksoft(NET_RX_SOFTIRQ);
+ 
+ 	net_rps_action_and_irq_enable(sd);
+ }
+@@ -7534,7 +7616,7 @@ EXPORT_SYMBOL(free_netdev);
+ void synchronize_net(void)
+ {
+ 	might_sleep();
+-	if (rtnl_is_locked())
++	if (rtnl_is_locked() && !IS_ENABLED(CONFIG_PREEMPT_RT_FULL))
+ 		synchronize_rcu_expedited();
+ 	else
+ 		synchronize_rcu();
+@@ -7775,16 +7857,20 @@ static int dev_cpu_callback(struct notifier_block *nfb,
+ 
+ 	raise_softirq_irqoff(NET_TX_SOFTIRQ);
+ 	local_irq_enable();
++	preempt_check_resched_rt();
+ 
+ 	/* Process offline CPU's input_pkt_queue */
+ 	while ((skb = __skb_dequeue(&oldsd->process_queue))) {
+ 		netif_rx_ni(skb);
+ 		input_queue_head_incr(oldsd);
+ 	}
+-	while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) {
++	while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) {
+ 		netif_rx_ni(skb);
+ 		input_queue_head_incr(oldsd);
+ 	}
++	while ((skb = __skb_dequeue(&oldsd->tofree_queue))) {
++		kfree_skb(skb);
++	}
+ 
+ 	return NOTIFY_OK;
+ }
+@@ -8086,8 +8172,9 @@ static int __init net_dev_init(void)
+ 	for_each_possible_cpu(i) {
+ 		struct softnet_data *sd = &per_cpu(softnet_data, i);
+ 
+-		skb_queue_head_init(&sd->input_pkt_queue);
+-		skb_queue_head_init(&sd->process_queue);
++		skb_queue_head_init_raw(&sd->input_pkt_queue);
++		skb_queue_head_init_raw(&sd->process_queue);
++		skb_queue_head_init_raw(&sd->tofree_queue);
+ 		INIT_LIST_HEAD(&sd->poll_list);
+ 		sd->output_queue_tailp = &sd->output_queue;
+ #ifdef CONFIG_RPS
+diff --git a/net/core/skbuff.c b/net/core/skbuff.c
+index 59bf4d77154f..0c1e29b0f8fb 100644
+--- a/net/core/skbuff.c
++++ b/net/core/skbuff.c
+@@ -63,6 +63,7 @@
+ #include <linux/errqueue.h>
+ #include <linux/prefetch.h>
+ #include <linux/if_vlan.h>
++#include <linux/locallock.h>
+ 
+ #include <net/protocol.h>
+ #include <net/dst.h>
+@@ -359,6 +360,8 @@ struct napi_alloc_cache {
+ 
+ static DEFINE_PER_CPU(struct page_frag_cache, netdev_alloc_cache);
+ static DEFINE_PER_CPU(struct napi_alloc_cache, napi_alloc_cache);
++static DEFINE_LOCAL_IRQ_LOCK(netdev_alloc_lock);
++static DEFINE_LOCAL_IRQ_LOCK(napi_alloc_cache_lock);
+ 
+ static void *__netdev_alloc_frag(unsigned int fragsz, gfp_t gfp_mask)
+ {
+@@ -366,10 +369,10 @@ static void *__netdev_alloc_frag(unsigned int fragsz, gfp_t gfp_mask)
+ 	unsigned long flags;
+ 	void *data;
+ 
+-	local_irq_save(flags);
++	local_lock_irqsave(netdev_alloc_lock, flags);
+ 	nc = this_cpu_ptr(&netdev_alloc_cache);
+ 	data = __alloc_page_frag(nc, fragsz, gfp_mask);
+-	local_irq_restore(flags);
++	local_unlock_irqrestore(netdev_alloc_lock, flags);
+ 	return data;
+ }
+ 
+@@ -388,9 +391,13 @@ EXPORT_SYMBOL(netdev_alloc_frag);
+ 
+ static void *__napi_alloc_frag(unsigned int fragsz, gfp_t gfp_mask)
+ {
+-	struct napi_alloc_cache *nc = this_cpu_ptr(&napi_alloc_cache);
++	struct napi_alloc_cache *nc;
++	void *data;
+ 
+-	return __alloc_page_frag(&nc->page, fragsz, gfp_mask);
++	nc = &get_locked_var(napi_alloc_cache_lock, napi_alloc_cache);
++	data = __alloc_page_frag(&nc->page, fragsz, gfp_mask);
++	put_locked_var(napi_alloc_cache_lock, napi_alloc_cache);
++	return data;
+ }
+ 
+ void *napi_alloc_frag(unsigned int fragsz)
+@@ -437,13 +444,13 @@ struct sk_buff *__netdev_alloc_skb(struct net_device *dev, unsigned int len,
+ 	if (sk_memalloc_socks())
+ 		gfp_mask |= __GFP_MEMALLOC;
+ 
+-	local_irq_save(flags);
++	local_lock_irqsave(netdev_alloc_lock, flags);
+ 
+ 	nc = this_cpu_ptr(&netdev_alloc_cache);
+ 	data = __alloc_page_frag(nc, len, gfp_mask);
+ 	pfmemalloc = nc->pfmemalloc;
+ 
+-	local_irq_restore(flags);
++	local_unlock_irqrestore(netdev_alloc_lock, flags);
+ 
+ 	if (unlikely(!data))
+ 		return NULL;
+@@ -484,9 +491,10 @@ EXPORT_SYMBOL(__netdev_alloc_skb);
+ struct sk_buff *__napi_alloc_skb(struct napi_struct *napi, unsigned int len,
+ 				 gfp_t gfp_mask)
+ {
+-	struct napi_alloc_cache *nc = this_cpu_ptr(&napi_alloc_cache);
++	struct napi_alloc_cache *nc;
+ 	struct sk_buff *skb;
+ 	void *data;
++	bool pfmemalloc;
+ 
+ 	len += NET_SKB_PAD + NET_IP_ALIGN;
+ 
+@@ -504,7 +512,10 @@ struct sk_buff *__napi_alloc_skb(struct napi_struct *napi, unsigned int len,
+ 	if (sk_memalloc_socks())
+ 		gfp_mask |= __GFP_MEMALLOC;
+ 
++	nc = &get_locked_var(napi_alloc_cache_lock, napi_alloc_cache);
+ 	data = __alloc_page_frag(&nc->page, len, gfp_mask);
++	pfmemalloc = nc->page.pfmemalloc;
++	put_locked_var(napi_alloc_cache_lock, napi_alloc_cache);
+ 	if (unlikely(!data))
+ 		return NULL;
+ 
+@@ -515,7 +526,7 @@ struct sk_buff *__napi_alloc_skb(struct napi_struct *napi, unsigned int len,
+ 	}
+ 
+ 	/* use OR instead of assignment to avoid clearing of bits in mask */
+-	if (nc->page.pfmemalloc)
++	if (pfmemalloc)
+ 		skb->pfmemalloc = 1;
+ 	skb->head_frag = 1;
+ 
+@@ -759,23 +770,26 @@ EXPORT_SYMBOL(consume_skb);
+ 
+ void __kfree_skb_flush(void)
+ {
+-	struct napi_alloc_cache *nc = this_cpu_ptr(&napi_alloc_cache);
++	struct napi_alloc_cache *nc;
+ 
++	nc = &get_locked_var(napi_alloc_cache_lock, napi_alloc_cache);
+ 	/* flush skb_cache if containing objects */
+ 	if (nc->skb_count) {
+ 		kmem_cache_free_bulk(skbuff_head_cache, nc->skb_count,
+ 				     nc->skb_cache);
+ 		nc->skb_count = 0;
+ 	}
++	put_locked_var(napi_alloc_cache_lock, napi_alloc_cache);
+ }
+ 
+ static inline void _kfree_skb_defer(struct sk_buff *skb)
+ {
+-	struct napi_alloc_cache *nc = this_cpu_ptr(&napi_alloc_cache);
++	struct napi_alloc_cache *nc;
+ 
+ 	/* drop skb->head and call any destructors for packet */
+ 	skb_release_all(skb);
+ 
++	nc = &get_locked_var(napi_alloc_cache_lock, napi_alloc_cache);
+ 	/* record skb to CPU local list */
+ 	nc->skb_cache[nc->skb_count++] = skb;
+ 
+@@ -790,6 +804,7 @@ static inline void _kfree_skb_defer(struct sk_buff *skb)
+ 				     nc->skb_cache);
+ 		nc->skb_count = 0;
+ 	}
++	put_locked_var(napi_alloc_cache_lock, napi_alloc_cache);
+ }
+ void __kfree_skb_defer(struct sk_buff *skb)
+ {
+diff --git a/net/core/sock.c b/net/core/sock.c
+index 7e73c26b6bb4..885fe2ec43fb 100644
+--- a/net/core/sock.c
++++ b/net/core/sock.c
+@@ -2421,12 +2421,11 @@ void lock_sock_nested(struct sock *sk, int subclass)
+ 	if (sk->sk_lock.owned)
+ 		__lock_sock(sk);
+ 	sk->sk_lock.owned = 1;
+-	spin_unlock(&sk->sk_lock.slock);
++	spin_unlock_bh(&sk->sk_lock.slock);
+ 	/*
+ 	 * The sk_lock has mutex_lock() semantics here:
+ 	 */
+ 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
+-	local_bh_enable();
+ }
+ EXPORT_SYMBOL(lock_sock_nested);
+ 
+diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
+index 6333489771ed..c1f1d5030d37 100644
+--- a/net/ipv4/icmp.c
++++ b/net/ipv4/icmp.c
+@@ -69,6 +69,7 @@
+ #include <linux/jiffies.h>
+ #include <linux/kernel.h>
+ #include <linux/fcntl.h>
++#include <linux/sysrq.h>
+ #include <linux/socket.h>
+ #include <linux/in.h>
+ #include <linux/inet.h>
+@@ -891,6 +892,30 @@ static bool icmp_redirect(struct sk_buff *skb)
+ }
+ 
+ /*
++ * 32bit and 64bit have different timestamp length, so we check for
++ * the cookie at offset 20 and verify it is repeated at offset 50
++ */
++#define CO_POS0		20
++#define CO_POS1		50
++#define CO_SIZE		sizeof(int)
++#define ICMP_SYSRQ_SIZE	57
++
++/*
++ * We got a ICMP_SYSRQ_SIZE sized ping request. Check for the cookie
++ * pattern and if it matches send the next byte as a trigger to sysrq.
++ */
++static void icmp_check_sysrq(struct net *net, struct sk_buff *skb)
++{
++	int cookie = htonl(net->ipv4.sysctl_icmp_echo_sysrq);
++	char *p = skb->data;
++
++	if (!memcmp(&cookie, p + CO_POS0, CO_SIZE) &&
++	    !memcmp(&cookie, p + CO_POS1, CO_SIZE) &&
++	    p[CO_POS0 + CO_SIZE] == p[CO_POS1 + CO_SIZE])
++		handle_sysrq(p[CO_POS0 + CO_SIZE]);
++}
++
++/*
+  *	Handle ICMP_ECHO ("ping") requests.
+  *
+  *	RFC 1122: 3.2.2.6 MUST have an echo server that answers ICMP echo
+@@ -917,6 +942,11 @@ static bool icmp_echo(struct sk_buff *skb)
+ 		icmp_param.data_len	   = skb->len;
+ 		icmp_param.head_len	   = sizeof(struct icmphdr);
+ 		icmp_reply(&icmp_param, skb);
++
++		if (skb->len == ICMP_SYSRQ_SIZE &&
++		    net->ipv4.sysctl_icmp_echo_sysrq) {
++			icmp_check_sysrq(net, skb);
++		}
+ 	}
+ 	/* should there be an ICMP stat for ignored echos? */
+ 	return true;
+diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c
+index bc5196ea1bdf..fc646aa7fad7 100644
+--- a/net/ipv4/inet_connection_sock.c
++++ b/net/ipv4/inet_connection_sock.c
+@@ -603,7 +603,7 @@ static void reqsk_timer_handler(unsigned long data)
+ 		if (req->num_timeout++ == 0)
+ 			atomic_dec(&queue->young);
+ 		timeo = min(TCP_TIMEOUT_INIT << req->num_timeout, TCP_RTO_MAX);
+-		mod_timer_pinned(&req->rsk_timer, jiffies + timeo);
++		mod_timer(&req->rsk_timer, jiffies + timeo);
+ 		return;
+ 	}
+ drop:
+@@ -617,8 +617,9 @@ static void reqsk_queue_hash_req(struct request_sock *req,
+ 	req->num_timeout = 0;
+ 	req->sk = NULL;
+ 
+-	setup_timer(&req->rsk_timer, reqsk_timer_handler, (unsigned long)req);
+-	mod_timer_pinned(&req->rsk_timer, jiffies + timeout);
++	setup_pinned_timer(&req->rsk_timer, reqsk_timer_handler,
++			    (unsigned long)req);
++	mod_timer(&req->rsk_timer, jiffies + timeout);
+ 
+ 	inet_ehash_insert(req_to_sk(req), NULL);
+ 	/* before letting lookups find us, make sure all req fields
+diff --git a/net/ipv4/inet_timewait_sock.c b/net/ipv4/inet_timewait_sock.c
+index c67f9bd7699c..dfb6286f2e49 100644
+--- a/net/ipv4/inet_timewait_sock.c
++++ b/net/ipv4/inet_timewait_sock.c
+@@ -188,7 +188,8 @@ struct inet_timewait_sock *inet_twsk_alloc(const struct sock *sk,
+ 		tw->tw_prot	    = sk->sk_prot_creator;
+ 		atomic64_set(&tw->tw_cookie, atomic64_read(&sk->sk_cookie));
+ 		twsk_net_set(tw, sock_net(sk));
+-		setup_timer(&tw->tw_timer, tw_timer_handler, (unsigned long)tw);
++		setup_pinned_timer(&tw->tw_timer, tw_timer_handler,
++				   (unsigned long)tw);
+ 		/*
+ 		 * Because we use RCU lookups, we should not set tw_refcnt
+ 		 * to a non null value before everything is setup for this
+@@ -248,7 +249,7 @@ void __inet_twsk_schedule(struct inet_timewait_sock *tw, int timeo, bool rearm)
+ 
+ 	tw->tw_kill = timeo <= 4*HZ;
+ 	if (!rearm) {
+-		BUG_ON(mod_timer_pinned(&tw->tw_timer, jiffies + timeo));
++		BUG_ON(mod_timer(&tw->tw_timer, jiffies + timeo));
+ 		atomic_inc(&tw->tw_dr->tw_count);
+ 	} else {
+ 		mod_timer_pending(&tw->tw_timer, jiffies + timeo);
+diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c
+index 03112a3106ab..daa6c5184977 100644
+--- a/net/ipv4/sysctl_net_ipv4.c
++++ b/net/ipv4/sysctl_net_ipv4.c
+@@ -681,6 +681,13 @@ static struct ctl_table ipv4_net_table[] = {
+ 		.proc_handler	= proc_dointvec
+ 	},
+ 	{
++		.procname	= "icmp_echo_sysrq",
++		.data		= &init_net.ipv4.sysctl_icmp_echo_sysrq,
++		.maxlen		= sizeof(int),
++		.mode		= 0644,
++		.proc_handler	= proc_dointvec
++	},
++	{
+ 		.procname	= "icmp_ignore_bogus_error_responses",
+ 		.data		= &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
+ 		.maxlen		= sizeof(int),
+diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
+index dc27becb9b71..7815f28bc30b 100644
+--- a/net/mac80211/rx.c
++++ b/net/mac80211/rx.c
+@@ -3679,7 +3679,7 @@ void ieee80211_rx_napi(struct ieee80211_hw *hw, struct sk_buff *skb,
+ 	struct ieee80211_supported_band *sband;
+ 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
+ 
+-	WARN_ON_ONCE(softirq_count() == 0);
++	WARN_ON_ONCE_NONRT(softirq_count() == 0);
+ 
+ 	if (WARN_ON(status->band >= IEEE80211_NUM_BANDS))
+ 		goto drop;
+diff --git a/net/netfilter/core.c b/net/netfilter/core.c
+index f39276d1c2d7..10880c89d62f 100644
+--- a/net/netfilter/core.c
++++ b/net/netfilter/core.c
+@@ -22,11 +22,17 @@
+ #include <linux/proc_fs.h>
+ #include <linux/mutex.h>
+ #include <linux/slab.h>
++#include <linux/locallock.h>
+ #include <net/net_namespace.h>
+ #include <net/sock.h>
+ 
+ #include "nf_internals.h"
+ 
++#ifdef CONFIG_PREEMPT_RT_BASE
++DEFINE_LOCAL_IRQ_LOCK(xt_write_lock);
++EXPORT_PER_CPU_SYMBOL(xt_write_lock);
++#endif
++
+ static DEFINE_MUTEX(afinfo_mutex);
+ 
+ const struct nf_afinfo __rcu *nf_afinfo[NFPROTO_NUMPROTO] __read_mostly;
+diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
+index 8012f67ca5ae..dbfd52456676 100644
+--- a/net/packet/af_packet.c
++++ b/net/packet/af_packet.c
+@@ -63,6 +63,7 @@
+ #include <linux/if_packet.h>
+ #include <linux/wireless.h>
+ #include <linux/kernel.h>
++#include <linux/delay.h>
+ #include <linux/kmod.h>
+ #include <linux/slab.h>
+ #include <linux/vmalloc.h>
+@@ -694,7 +695,7 @@ static void prb_retire_rx_blk_timer_expired(unsigned long data)
+ 	if (BLOCK_NUM_PKTS(pbd)) {
+ 		while (atomic_read(&pkc->blk_fill_in_prog)) {
+ 			/* Waiting for skb_copy_bits to finish... */
+-			cpu_relax();
++			cpu_chill();
+ 		}
+ 	}
+ 
+@@ -956,7 +957,7 @@ static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
+ 		if (!(status & TP_STATUS_BLK_TMO)) {
+ 			while (atomic_read(&pkc->blk_fill_in_prog)) {
+ 				/* Waiting for skb_copy_bits to finish... */
+-				cpu_relax();
++				cpu_chill();
+ 			}
+ 		}
+ 		prb_close_block(pkc, pbd, po, status);
+diff --git a/net/rds/ib_rdma.c b/net/rds/ib_rdma.c
+index f7164ac1ffc1..6f37dd5fc717 100644
+--- a/net/rds/ib_rdma.c
++++ b/net/rds/ib_rdma.c
+@@ -34,6 +34,7 @@
+ #include <linux/slab.h>
+ #include <linux/rculist.h>
+ #include <linux/llist.h>
++#include <linux/delay.h>
+ 
+ #include "ib_mr.h"
+ 
+@@ -209,7 +210,7 @@ static inline void wait_clean_list_grace(void)
+ 	for_each_online_cpu(cpu) {
+ 		flag = &per_cpu(clean_list_grace, cpu);
+ 		while (test_bit(CLEAN_LIST_BUSY_BIT, flag))
+-			cpu_relax();
++			cpu_chill();
+ 	}
+ }
+ 
+diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
+index 80742edea96f..31f70ee7e609 100644
+--- a/net/sched/sch_generic.c
++++ b/net/sched/sch_generic.c
+@@ -894,7 +894,7 @@ void dev_deactivate_many(struct list_head *head)
+ 	/* Wait for outstanding qdisc_run calls. */
+ 	list_for_each_entry(dev, head, close_list)
+ 		while (some_qdisc_is_busy(dev))
+-			yield();
++			msleep(1);
+ }
+ 
+ void dev_deactivate(struct net_device *dev)
+diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
+index 7231cb413a2c..e9c57cd2cb7c 100644
+--- a/net/sunrpc/svc_xprt.c
++++ b/net/sunrpc/svc_xprt.c
+@@ -344,7 +344,7 @@ void svc_xprt_do_enqueue(struct svc_xprt *xprt)
+ 		goto out;
+ 	}
+ 
+-	cpu = get_cpu();
++	cpu = get_cpu_light();
+ 	pool = svc_pool_for_cpu(xprt->xpt_server, cpu);
+ 
+ 	atomic_long_inc(&pool->sp_stats.packets);
+@@ -380,7 +380,7 @@ void svc_xprt_do_enqueue(struct svc_xprt *xprt)
+ 
+ 		atomic_long_inc(&pool->sp_stats.threads_woken);
+ 		wake_up_process(rqstp->rq_task);
+-		put_cpu();
++		put_cpu_light();
+ 		goto out;
+ 	}
+ 	rcu_read_unlock();
+@@ -401,7 +401,7 @@ void svc_xprt_do_enqueue(struct svc_xprt *xprt)
+ 		goto redo_search;
+ 	}
+ 	rqstp = NULL;
+-	put_cpu();
++	put_cpu_light();
+ out:
+ 	trace_svc_xprt_do_enqueue(xprt, rqstp);
+ }
+diff --git a/scripts/mkcompile_h b/scripts/mkcompile_h
+index 6fdc97ef6023..523e0420d7f0 100755
+--- a/scripts/mkcompile_h
++++ b/scripts/mkcompile_h
+@@ -4,7 +4,8 @@ TARGET=$1
+ ARCH=$2
+ SMP=$3
+ PREEMPT=$4
+-CC=$5
++RT=$5
++CC=$6
+ 
+ vecho() { [ "${quiet}" = "silent_" ] || echo "$@" ; }
+ 
+@@ -57,6 +58,7 @@ UTS_VERSION="#$VERSION"
+ CONFIG_FLAGS=""
+ if [ -n "$SMP" ] ; then CONFIG_FLAGS="SMP"; fi
+ if [ -n "$PREEMPT" ] ; then CONFIG_FLAGS="$CONFIG_FLAGS PREEMPT"; fi
++if [ -n "$RT" ] ; then CONFIG_FLAGS="$CONFIG_FLAGS RT"; fi
+ UTS_VERSION="$UTS_VERSION $CONFIG_FLAGS $TIMESTAMP"
+ 
+ # Truncate to maximum length
+diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
+index 9106d8e2300e..6c55707fdc30 100644
+--- a/sound/core/pcm_native.c
++++ b/sound/core/pcm_native.c
+@@ -135,7 +135,7 @@ EXPORT_SYMBOL_GPL(snd_pcm_stream_unlock);
+ void snd_pcm_stream_lock_irq(struct snd_pcm_substream *substream)
+ {
+ 	if (!substream->pcm->nonatomic)
+-		local_irq_disable();
++		local_irq_disable_nort();
+ 	snd_pcm_stream_lock(substream);
+ }
+ EXPORT_SYMBOL_GPL(snd_pcm_stream_lock_irq);
+@@ -150,7 +150,7 @@ void snd_pcm_stream_unlock_irq(struct snd_pcm_substream *substream)
+ {
+ 	snd_pcm_stream_unlock(substream);
+ 	if (!substream->pcm->nonatomic)
+-		local_irq_enable();
++		local_irq_enable_nort();
+ }
+ EXPORT_SYMBOL_GPL(snd_pcm_stream_unlock_irq);
+ 
+@@ -158,7 +158,7 @@ unsigned long _snd_pcm_stream_lock_irqsave(struct snd_pcm_substream *substream)
+ {
+ 	unsigned long flags = 0;
+ 	if (!substream->pcm->nonatomic)
+-		local_irq_save(flags);
++		local_irq_save_nort(flags);
+ 	snd_pcm_stream_lock(substream);
+ 	return flags;
+ }
+@@ -176,7 +176,7 @@ void snd_pcm_stream_unlock_irqrestore(struct snd_pcm_substream *substream,
+ {
+ 	snd_pcm_stream_unlock(substream);
+ 	if (!substream->pcm->nonatomic)
+-		local_irq_restore(flags);
++		local_irq_restore_nort(flags);
+ }
+ EXPORT_SYMBOL_GPL(snd_pcm_stream_unlock_irqrestore);
+ 
diff --git a/target/linux/patches/4.6.4/revert-sparc.patch b/target/linux/patches/4.6.5/revert-sparc.patch
index d5bb8ad37..d5bb8ad37 100644
--- a/target/linux/patches/4.6.4/revert-sparc.patch
+++ b/target/linux/patches/4.6.5/revert-sparc.patch
diff --git a/target/linux/patches/4.6.4/startup.patch b/target/linux/patches/4.6.5/startup.patch
index e54ac19a6..e54ac19a6 100644
--- a/target/linux/patches/4.6.4/startup.patch
+++ b/target/linux/patches/4.6.5/startup.patch