[RFC PATCH V2 2/3] sched/fair: Do not consider the sched-delayed task when yield

[Xuewen Yan]

When task call sched_yield, if there is only one task in rq,
it is no need to yield, however now, the rq->nr_running include
the sched-delayed tasks which are indeed not runnable tasks.
So sub the sched-delayed tasks when check the nr-running.

Fixes: 152e11f6df29 ("sched/fair: Implement delayed dequeue")
Signed-off-by: Xuewen Yan <xuewen.yan@xxxxxxxxxx>
---
 kernel/sched/fair.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index a354f29c4f6f..8797f6872155 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -8992,7 +8992,7 @@ static void yield_task_fair(struct rq *rq)
 	/*
 	 * Are we the only task in the tree?
 	 */
-	if (unlikely(rq->nr_running == 1))
+	if (unlikely((rq->nr_running - cfs_h_nr_delayed(rq)) == 1))
 		return;
 
 	clear_buddies(cfs_rq, se);
-- 
2.25.1