[lkml]   [2021]   [Jul]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Subject[GIT PULL] posix-cpu-timers leftover overhead fixes
Thomas, Ingo,

Please pull the timers/core branch that can be found at:


HEAD: 63a17eea7d5516f9e927fdc52b45f1d040fdcf35


Those are not regression fixes since these bugs precede the git-era,
therefore they are not carrying a stable tag.

Several posix cpu timers events (setting, deletion, expiration) may end
up leaving needless elapsing overhead after a timer has stopped or
even after it has been deleted. Those overhead are:

1) Costly process wide cputime accounting that rely on concurrent atomic
addition during tick or even more frequent scheduler internal stat updates.

2) Retained tick dependency on NOHZ_FULL configurations.

Hopefully this series gets rid of all the possible culprits.


Frederic Weisbecker (6):
posix-cpu-timers: Assert task sighand is locked while starting cputime counter
posix-cpu-timers: Force next_expiration recalc after timer deletion
posix-cpu-timers: Force next expiration recalc after itimer reset
posix-cpu-timers: Remove confusing error code override
posix-cpu-timers: Consolidate timer base accessor
posix-cpu-timers: Recalc next expiration when timer_settime() ends up not queueing

include/linux/posix-timers.h | 11 +++++-
include/linux/sched/signal.h | 6 +++
kernel/signal.c | 15 +++++++
kernel/time/posix-cpu-timers.c | 90 ++++++++++++++++++++++++++++++++++--------
4 files changed, 103 insertions(+), 19 deletions(-)

 \ /
  Last update: 2021-07-26 14:56    [W:0.074 / U:0.396 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site