linux/kernel/time
Jason Low 7c177d994e posix_cpu_timer: Optimize fastpath_timer_check()
In fastpath_timer_check(), the task_cputime() function is always
called to compute the utime and stime values. However, this is not
necessary if there are no per-thread timers to check for. This patch
modifies the code such that we compute the task_cputime values only
when there are per-thread timers set.

Signed-off-by: Jason Low <jason.low2@hp.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Reviewed-by: George Spelvin <linux@horizon.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: hideaki.kimura@hpe.com
Cc: terry.rudd@hpe.com
Cc: scott.norton@hpe.com
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1444849677-29330-2-git-send-email-jason.low2@hp.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-10-15 11:23:41 +02:00
..
alarmtimer.c alarmtimer: Get rid of unused return value 2015-04-22 17:06:52 +02:00
clockevents.c clockevents: Remove unused set_mode() callback 2015-09-14 11:00:55 +02:00
clocksource.c Linux 4.3-rc5 2015-10-12 09:51:18 +02:00
hrtimer.c time: Fix spelling in comments 2015-09-22 12:54:23 +02:00
itimer.c time/timers: Move all time(r) related files into kernel/time 2014-06-23 11:22:35 +02:00
jiffies.c tick: Move clocksource related stuff to timekeeping.h 2015-04-01 14:22:58 +02:00
Kconfig rcu: Drop RCU_USER_QS in favor of NO_HZ_FULL 2015-07-06 13:52:18 -07:00
Makefile time: Remove development rules from Kbuild/Makefile 2015-07-01 09:57:35 +02:00
ntp_internal.h time: Prevent early expiry of hrtimers[CLOCK_REALTIME] at the leap second edge 2015-06-12 11:15:49 +02:00
ntp.c time: Add the common weak version of update_persistent_clock() 2015-08-17 11:25:16 -07:00
posix-clock.c kernel: Fix files explicitly needing EXPORT_SYMBOL infrastructure 2011-10-31 19:30:05 -04:00
posix-cpu-timers.c posix_cpu_timer: Optimize fastpath_timer_check() 2015-10-15 11:23:41 +02:00
posix-timers.c hrtimer: Get rid of hrtimer_get_res() 2015-04-22 17:06:49 +02:00
sched_clock.c timers, sched/clock: Clean up the code a bit 2015-03-27 08:34:01 +01:00
test_udelay.c time: Rename udelay_test.c to test_udelay.c 2014-11-21 11:59:55 -08:00
tick-broadcast-hrtimer.c kernel: broadcast-hrtimer: Migrate to new 'set-state' interface 2015-08-10 11:41:08 +02:00
tick-broadcast.c tick: Move the export of tick_broadcast_oneshot_control to the proper place 2015-07-14 12:01:04 +02:00
tick-common.c clockevents: Remove unused set_mode() callback 2015-09-14 11:00:55 +02:00
tick-internal.h timer: Minimize nohz off overhead 2015-06-19 15:18:28 +02:00
tick-oneshot.c clockevents: Provide functions to set and get the state 2015-06-02 14:40:47 +02:00
tick-sched.c nohz: Assert existing housekeepers when nohz full enabled 2015-09-02 10:33:22 +02:00
tick-sched.h tick/broadcast: Make idle check independent from mode and config 2015-07-07 18:46:47 +02:00
time.c Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 14:04:50 -07:00
timeconst.bc time: Move timeconst.h into include/generated 2015-05-19 15:13:45 +02:00
timeconv.c
timecounter.c timecounter: keep track of accumulated fractional nanoseconds 2014-12-30 18:29:27 -05:00
timekeeping_debug.c timekeeping: Convert timekeeping core to use timespec64s 2014-07-23 10:17:54 -07:00
timekeeping_internal.h clocksource: Move cycle_last validation to core code 2014-07-23 15:01:51 -07:00
timekeeping.c time: Fix spelling in comments 2015-09-22 12:54:23 +02:00
timekeeping.h hrtimer: Make offset update smarter 2015-04-22 17:06:49 +02:00
timer_list.c clockevents: Remove unused set_mode() callback 2015-09-14 11:00:55 +02:00
timer_stats.c timer: Stats: Simplify the flags handling 2015-06-19 15:18:27 +02:00
timer.c timers: Use __fls in apply_slack() 2015-10-11 22:13:46 +02:00