github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-05-28 17:13:52 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

tick/nohz: Optimize check_tick_dependency() with early return

Browse Source 
There is no point in iterating through individual tick dependency bits when
the tick_stop tracepoint is disabled, which is the common case.

When the trace point is disabled, return immediately based on the atomic
value being zero or non-zero, skipping the per-bit evaluation.

This optimization improves the hot path performance of tick dependency
checks across all contexts (idle and non-idle), not just nohz_full CPUs.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ionut Nechita (Sunlight Linux) <sunlightlinux@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260128074558.15433-3-sunlightlinux@gmail.com
This commit is contained in:
Ionut Nechita (Sunlight Linux) 2026-01-28 09:45:43 +02:00 committed by Thomas Gleixner
parent 3db5306b0b
commit 56534673ce
1 changed files with 3 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
kernel/time/tick-sched.c
View File

@ -344,6 +344,9 @@ static bool check_tick_dependency(atomic_t *dep)
{ {
int val = atomic_read(dep); int val = atomic_read(dep);
if (likely(!tracepoint_enabled(tick_stop)))
return !val;
if (val & TICK_DEP_MASK_POSIX_TIMER) { if (val & TICK_DEP_MASK_POSIX_TIMER) {
trace_tick_stop(0, TICK_DEP_MASK_POSIX_TIMER); trace_tick_stop(0, TICK_DEP_MASK_POSIX_TIMER);
return true; return true;