sched/fair: Fix cfs_rq_is_decayed() on !SMP
authorChengming Zhou <zhouchengming@bytedance.com>
Wed, 13 Sep 2023 13:20:31 +0000 (13:20 +0000)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Mon, 20 Nov 2023 10:58:51 +0000 (11:58 +0100)
[ 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@andestech.com>
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Leo Yu-Chi Liang <ycliang@andestech.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Closes: https://lore.kernel.org/all/ZN87UsqkWcFLDxea@swlinux02/
Link: https://lore.kernel.org/r/20230913132031.2242151-1-chengming.zhou@linux.dev
Signed-off-by: Sasha Levin <sashal@kernel.org>
kernel/sched/fair.c

index df348aa..6af1d48 100644 (file)
@@ -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