summary refs log tree commit diff
path: root/scripts/recordmcount.h
diff options
context:
space:
mode:
authorPeter Zijlstra <peterz@infradead.org>2020-12-10 17:14:08 +0100
committerPeter Zijlstra <peterz@infradead.org>2020-12-15 11:27:53 +0100
commitae7927023243dcc7389b2d59b16c09cbbeaecc36 (patch)
tree64bdf7a8cddcc7a2c2631a107dee1b5bbc4e7405 /scripts/recordmcount.h
parent5b78f2dc315354c05300795064f587366a02c6ff (diff)
downloadlinux-ae7927023243dcc7389b2d59b16c09cbbeaecc36.tar.gz
sched: Optimize finish_lock_switch()
The kernel test robot measured a -1.6% performance regression on
will-it-scale/sched_yield due to commit:

  2558aacff858 ("sched/hotplug: Ensure only per-cpu kthreads run during hotplug")

Even though we were careful to replace a single load with another
single load from the same cacheline.

Restore finish_lock_switch() to the exact state before the offending
patch and solve the problem differently.

Fixes: 2558aacff858 ("sched/hotplug: Ensure only per-cpu kthreads run during hotplug")
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20201210161408.GX3021@hirez.programming.kicks-ass.net
Diffstat (limited to 'scripts/recordmcount.h')
0 files changed, 0 insertions, 0 deletions