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d269a8b8c57523a2e328c1ff44fe791e13df3d37
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Davidlohr Bueso d269a8b8c5 kernel/locking: Compute 'current' directly 
This patch effectively replaces the tsk pointer dereference
(which is obviously == current), to directly use get_current()
macro. This is to make the removal of setting foreign task
states smoother and painfully obvious. Performance win on some
archs such as x86-64 and ppc64. On a microbenchmark that calls
set_task_state() vs set_current_state() and an inode rwsem
pounding benchmark doing unlink:

== 1. x86-64 ==

Avg runtime set_task_state():    601 msecs
Avg runtime set_current_state(): 552 msecs

                                            vanilla                 dirty
Hmean    unlink1-processes-2      36089.26 (  0.00%)    38977.33 (  8.00%)
Hmean    unlink1-processes-5      28555.01 (  0.00%)    29832.55 (  4.28%)
Hmean    unlink1-processes-8      37323.75 (  0.00%)    44974.57 ( 20.50%)
Hmean    unlink1-processes-12     43571.88 (  0.00%)    44283.01 (  1.63%)
Hmean    unlink1-processes-21     34431.52 (  0.00%)    38284.45 ( 11.19%)
Hmean    unlink1-processes-30     34813.26 (  0.00%)    37975.17 (  9.08%)
Hmean    unlink1-processes-48     37048.90 (  0.00%)    39862.78 (  7.59%)
Hmean    unlink1-processes-79     35630.01 (  0.00%)    36855.30 (  3.44%)
Hmean    unlink1-processes-110    36115.85 (  0.00%)    39843.91 ( 10.32%)
Hmean    unlink1-processes-141    32546.96 (  0.00%)    35418.52 (  8.82%)
Hmean    unlink1-processes-172    34674.79 (  0.00%)    36899.21 (  6.42%)
Hmean    unlink1-processes-203    37303.11 (  0.00%)    36393.04 ( -2.44%)
Hmean    unlink1-processes-224    35712.13 (  0.00%)    36685.96 (  2.73%)

== 2. ppc64le ==

Avg runtime set_task_state():  938 msecs
Avg runtime set_current_state: 940 msecs

                                            vanilla                 dirty
Hmean    unlink1-processes-2      19269.19 (  0.00%)    30704.50 ( 59.35%)
Hmean    unlink1-processes-5      20106.15 (  0.00%)    21804.15 (  8.45%)
Hmean    unlink1-processes-8      17496.97 (  0.00%)    17243.28 ( -1.45%)
Hmean    unlink1-processes-12     14224.15 (  0.00%)    17240.21 ( 21.20%)
Hmean    unlink1-processes-21     14155.66 (  0.00%)    15681.23 ( 10.78%)
Hmean    unlink1-processes-30     14450.70 (  0.00%)    15995.83 ( 10.69%)
Hmean    unlink1-processes-48     16945.57 (  0.00%)    16370.42 ( -3.39%)
Hmean    unlink1-processes-79     15788.39 (  0.00%)    14639.27 ( -7.28%)
Hmean    unlink1-processes-110    14268.48 (  0.00%)    14377.40 (  0.76%)
Hmean    unlink1-processes-141    14023.65 (  0.00%)    16271.69 ( 16.03%)
Hmean    unlink1-processes-172    13417.62 (  0.00%)    16067.55 ( 19.75%)
Hmean    unlink1-processes-203    15293.08 (  0.00%)    15440.40 (  0.96%)
Hmean    unlink1-processes-234    13719.32 (  0.00%)    16190.74 ( 18.01%)
Hmean    unlink1-processes-265    16400.97 (  0.00%)    16115.22 ( -1.74%)
Hmean    unlink1-processes-296    14388.60 (  0.00%)    16216.13 ( 12.70%)
Hmean    unlink1-processes-320    15771.85 (  0.00%)    15905.96 (  0.85%)

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dave@stgolabs.net
Cc: mark.rutland@arm.com
Link: http://lkml.kernel.org/r/1483479794-14013-4-git-send-email-dave@stgolabs.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-14 11:14:14 +01:00
..
bpf
bpf: do not use KMALLOC_SHIFT_MAX
2017-01-10 18:31:54 -08:00
configs
config: android: enable CONFIG_SECCOMP
2016-10-11 15:06:32 -07:00
debug
kdb: call vkdb_printf() from vprintk_default() only when wanted
2016-12-14 16:04:08 -08:00
events
Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2016-12-23 16:49:12 -08:00
gcov
…
irq
genirq/affinity: Fix node generation from cpumask
2016-12-15 12:32:35 +01:00
livepatch
livepatch/module: make TAINT_LIVEPATCH module-specific
2016-08-26 14:42:08 +02:00
locking
kernel/locking: Compute 'current' directly
2017-01-14 11:14:14 +01:00
power
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
printk
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
rcu
rcu: Don't kick unless grace period or request
2016-11-14 10:46:31 -08:00
sched
ktime: Cleanup ktime_set() usage
2016-12-25 17:21:22 +01:00
time
ktime: Cleanup ktime_set() usage
2016-12-25 17:21:22 +01:00
trace
clocksource: Use a plain u64 instead of cycle_t
2016-12-25 11:04:12 +01:00
.gitignore
…
acct.c
…
async.c
…
audit_fsnotify.c
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2016-12-17 18:44:00 -08:00
audit_tree.c
Merge branch 'stable-4.10' of git://git.infradead.org/users/pcmoore/audit
2017-01-05 23:06:06 -08:00
audit_watch.c
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2016-12-17 18:44:00 -08:00
audit.c
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2016-12-17 18:44:00 -08:00
audit.h
audit_log_{name,link_denied}: constify struct path
2016-12-05 19:00:38 -05:00
auditfilter.c
audit: add support for session ID user filter
2016-11-29 15:10:12 -05:00
auditsc.c
Merge branch 'stable-4.10' of git://git.infradead.org/users/pcmoore/audit
2016-12-14 14:06:40 -08:00
backtracetest.c
…
bounds.c
…
capability.c
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
cgroup_freezer.c
…
cgroup_pids.c
…
cgroup.c
cgroup: add support for eBPF programs
2016-11-25 16:25:52 -05:00
compat.c
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
configs.c
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
context_tracking.c
…
cpu_pm.c
…
cpu.c
smp/hotplug: Undo tglxs brainfart
2016-12-26 17:30:24 -08:00
cpuset.c
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
crash_dump.c
…
cred.c
…
delayacct.c
…
dma.c
…
elfcore.c
…
exec_domain.c
…
exit.c
kernel/exit: Compute 'current' directly
2017-01-14 11:14:11 +01:00
extable.c
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
fork.c
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
freezer.c
freezer, oom: check TIF_MEMDIE on the correct task
2016-07-28 16:07:41 -07:00
futex_compat.c
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
futex.c
ktime: Get rid of the union
2016-12-25 17:21:22 +01:00
groups.c
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
hung_task.c
hung_task: decrement sysctl_hung_task_warnings only if it is positive
2016-12-12 18:55:09 -08:00
irq_work.c
…
jump_label.c
Merge tag 'powerpc-4.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
2016-08-05 09:00:54 -04:00
kallsyms.c
…
kcmp.c
…
Kconfig.freezer
…
Kconfig.hz
…
Kconfig.locks
locking/mutex: Allow MUTEX_SPIN_ON_OWNER when DEBUG_MUTEXES
2016-10-25 11:31:51 +02:00
Kconfig.preempt
…
kcov.c
kcov: make kcov work properly with KASLR enabled
2016-12-20 09:48:47 -08:00
kexec_core.c
kexec: add cond_resched into kimage_alloc_crash_control_pages
2016-12-14 16:04:07 -08:00
kexec_file.c
ima: on soft reboot, save the measurement list
2016-12-20 09:48:44 -08:00
kexec_internal.h
kexec_file: Allow arch-specific memory walking for kexec_add_buffer
2016-11-30 23:14:57 +11:00
kexec.c
kexec: allow architectures to override boot mapping
2016-08-02 19:35:27 -04:00
kmod.c
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
kprobes.c
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
ksysfs.c
kexec: add a kexec_crash_loaded() function
2016-08-02 19:35:30 -04:00
kthread.c
kthread: add __printf attributes
2016-12-12 18:55:06 -08:00
latencytop.c
…
Makefile
Merge branch 'akpm' (patches from Andrew)
2016-12-14 17:25:18 -08:00
membarrier.c
…
memremap.c
mm: fix devm_memremap_pages crash, use mem_hotplug_{begin, done}
2017-01-10 18:31:54 -08:00
module_signing.c
…
module-internal.h
…
module.c
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
notifier.c
…
nsproxy.c
…
padata.c
padata: Remove unused but set variables
2016-10-25 11:08:10 +08:00
panic.c
taint/module: Clean up global and module taint flags handling
2016-11-26 11:18:01 -08:00
params.c
…
pid_namespace.c
Merge branch 'nsfs-ioctls' into HEAD
2016-09-22 20:00:36 -05:00
pid.c
…
profile.c
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
ptrace.c
ptrace: Don't allow accessing an undumpable mm
2016-11-22 12:57:38 -06:00
range.c
…
reboot.c
…
relay.c
relay: check array offset before using it
2016-12-14 16:04:08 -08:00
resource.c
…
seccomp.c
Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
2016-12-14 13:57:44 -08:00
signal.c
signal: protect SIGNAL_UNKILLABLE from unintentional clearing.
2017-01-10 18:31:55 -08:00
smp.c
kernel/smp: Tell the user we're bringing up secondary CPUs
2016-10-26 12:02:35 +02:00
smpboot.c
kthread/smpboot: do not park in kthread_create_on_cpu()
2016-10-11 15:06:33 -07:00
smpboot.h
…
softirq.c
softirq: Display IRQ_POLL for irq-poll statistics
2016-10-21 15:45:47 -06:00
stacktrace.c
…
stop_machine.c
locking/core, stop_machine: Yield the CPU during stop machine()
2016-11-16 10:15:09 +01:00
sys_ni.c
move aio compat to fs/aio.c
2016-12-22 22:58:37 -05:00
sys.c
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
sysctl_binary.c
sysctl: add KERN_CONT to deprecated_sysctl_warning()
2016-12-14 16:04:07 -08:00
sysctl.c
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
task_work.c
task_work: use READ_ONCE/lockless_dereference, avoid pi_lock if !task_works
2016-08-02 19:35:02 -04:00
taskstats.c
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
2016-11-15 10:54:36 -05:00
test_kprobes.c
…
torture.c
torture: Convert torture_shutdown() to hrtimer
2016-08-22 10:01:49 -07:00
tracepoint.c
tracing: Have the reg function allow to fail
2016-12-09 09:13:30 -05:00
tsacct.c
…
ucount.c
mntns: Add a limit on the number of mount namespaces.
2016-08-31 07:28:35 -05:00
uid16.c
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
up.c
smp: Add function to execute a function synchronously on a CPU
2016-09-05 13:52:39 +02:00
user_namespace.c
Merge branch 'nsfs-ioctls' into HEAD
2016-09-22 20:00:36 -05:00
user-return-notifier.c
…
user.c
…
utsname_sysctl.c
…
utsname.c
Merge branch 'nsfs-ioctls' into HEAD
2016-09-22 20:00:36 -05:00
watchdog_hld.c
kernel/watchdog.c: move hardlockup detector to separate file
2016-12-14 16:04:08 -08:00
watchdog.c
kernel/watchdog.c: move hardlockup detector to separate file
2016-12-14 16:04:08 -08:00
workqueue_internal.h
…
workqueue.c
Merge branch 'for-4.9' into for-4.10
2016-10-19 12:12:40 -04:00