sched_ext: Count rq lock releases in rq->scx.lock_drop_seq

Browse source

Under core scheduling, pick_next_task() selects for all SMT siblings under
one continuous hold of the shared core-wide rq lock, and sched_ext's
dispatch can release that lock from inside the pick. In preparation for
making the core-sched pick detect the releases and retry, add
rq->scx.lock_drop_seq and bump it at every site that can release an rq lock
while a dispatch may be in flight. The counter is only maintained while core
scheduling is enabled. No functional changes.

Fixes: 4c95380701 ("sched/ext: Fold balance_scx() into pick_task_scx()")
Cc: stable@vger.kernel.org # v6.19+
Signed-off-by: Tejun Heo <tj@kernel.org>

...

This commit is contained in:

Tejun Heo 2026-08-07 11:02:20 -10:00

parent 3dd52416e4

commit f2da958711

2 changed files with 39 additions and 2 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

38

kernel/sched/ext/ext.c

View file

3

kernel/sched/sched.h

View file