linux/kernel/time
Peter Zijlstra 5167e8d541 sched/nohz: Rewrite and fix load-avg computation -- again
Thanks to Charles Wang for spotting the defects in the current code:

 - If we go idle during the sample window -- after sampling, we get a
   negative bias because we can negate our own sample.

 - If we wake up during the sample window we get a positive bias
   because we push the sample to a known active period.

So rewrite the entire nohz load-avg muck once again, now adding
copious documentation to the code.

Reported-and-tested-by: Doug Smythies <dsmythies@telus.net>
Reported-and-tested-by: Charles Wang <muming.wq@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: stable@kernel.org
Link: http://lkml.kernel.org/r/1340373782.18025.74.camel@twins
[ minor edits ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-05 20:58:13 +02:00
..
alarmtimer.c alarmtimer: Provide accessor to alarmtimer rtc device 2012-04-20 14:56:36 -07:00
clockevents.c clockevents: Make clockevents_config() a global symbol 2012-05-25 01:44:51 +02:00
clocksource.c kernel-time: fix s/then/than/ spelling errors 2012-03-23 16:49:21 -07:00
jiffies.c Fix common misspellings 2011-03-31 11:26:23 -03:00
Kconfig timers: Fixup the Kconfig consolidation fallout 2012-05-21 23:43:46 +02:00
Makefile timers: Introduce in-kernel alarm-timer interface 2011-04-26 14:01:44 -07:00
ntp.c ntp: Fix a stale comment and a few stray newlines. 2012-05-21 16:16:56 -07:00
posix-clock.c kernel: Fix files explicitly needing EXPORT_SYMBOL infrastructure 2011-10-31 19:30:05 -04:00
tick-broadcast.c tick: Fix the spurious broadcast timer ticks after resume 2012-04-19 21:27:50 +02:00
tick-common.c clockevents: Make minimum delay adjustments configurable 2011-09-08 11:10:56 +02:00
tick-internal.h clockevents: Make minimum delay adjustments configurable 2011-09-08 11:10:56 +02:00
tick-oneshot.c clockevents: Make minimum delay adjustments configurable 2011-09-08 11:10:56 +02:00
tick-sched.c sched/nohz: Rewrite and fix load-avg computation -- again 2012-07-05 20:58:13 +02:00
timecompare.c time: Use ARRAY_SIZE macro in timecompare.c 2010-10-21 17:30:06 +02:00
timeconv.c time: add function to convert between calendar time and broken-down time for universal use 2009-09-24 07:20:56 -07:00
timekeeping.c timekeeping: Fix CLOCK_MONOTONIC inconsistency during leapsecond 2012-06-04 21:46:29 +02:00
timer_list.c timer debug: Hide kernel addresses via %pK in /proc/timer_list 2011-02-12 14:11:56 +01:00
timer_stats.c locking, timer_stats: Annotate table_lock as raw 2011-09-13 11:12:00 +02:00