This is a note to let you know that I've just added the patch titled
sched/fair: Fix cfs_rq_is_decayed() on !SMP
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
sched-fair-fix-cfs_rq_is_decayed-on-smp.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit f0faa940ccf50634148d43fd74454ef7d32c297d
Author: Chengming Zhou <zhouchengming@xxxxxxxxxxxxx>
Date: Wed Sep 13 13:20:31 2023 +0000
sched/fair: Fix cfs_rq_is_decayed() on !SMP
[ Upstream commit c0490bc9bb62d9376f3dd4ec28e03ca0fef97152 ]
We don't need to maintain per-queue leaf_cfs_rq_list on !SMP, since
it's used for cfs_rq load tracking & balancing on SMP.
But sched debug interface uses it to print per-cfs_rq stats.
This patch fixes the !SMP version of cfs_rq_is_decayed(), so the
per-queue leaf_cfs_rq_list is also maintained correctly on !SMP,
to fix the warning in assert_list_leaf_cfs_rq().
Fixes: 0a00a354644e ("sched/fair: Delete useless condition in tg_unthrottle_up()")
Reported-by: Leo Yu-Chi Liang <ycliang@xxxxxxxxxxxxx>
Signed-off-by: Chengming Zhou <zhouchengming@xxxxxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Tested-by: Leo Yu-Chi Liang <ycliang@xxxxxxxxxxxxx>
Reviewed-by: Vincent Guittot <vincent.guittot@xxxxxxxxxx>
Closes: https://lore.kernel.org/all/ZN87UsqkWcFLDxea@swlinux02/
Link: https://lore.kernel.org/r/20230913132031.2242151-1-chengming.zhou@xxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index df348aa55d3c7..6af1d48d467ed 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -4932,7 +4932,7 @@ static inline void update_misfit_status(struct task_struct *p, struct rq *rq)
static inline bool cfs_rq_is_decayed(struct cfs_rq *cfs_rq)
{
- return true;
+ return !cfs_rq->nr_running;
}
#define UPDATE_TG 0x0
