sched/fair: Assert {set_next,put_prev}_entity() are properly balanced

Peter Zijlstra · Peter Zijlstra · commit e28b5f8bda01 · 2024-08-17T11:06:42.000+02:00
Just a little sanity test.. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Valentin Schneider <vschneid@redhat.com> Tested-by: Valentin Schneider <vschneid@redhat.com> Link: https://lkml.kernel.org/r/20240727105029.486423066@infradead.org
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
@@ -5452,6 +5452,7 @@ set_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
 	}
 
 	update_stats_curr_start(cfs_rq, se);
+	SCHED_WARN_ON(cfs_rq->curr);
 	cfs_rq->curr = se;
 
 	/*
@@ -5513,6 +5514,7 @@ static void put_prev_entity(struct cfs_rq *cfs_rq, struct sched_entity *prev)
 		/* in !on_rq case, update occurred at dequeue */
 		update_load_avg(cfs_rq, prev, 0);
 	}
+	SCHED_WARN_ON(cfs_rq->curr != prev);
 	cfs_rq->curr = NULL;
 }
 

Original file line number	Diff line number	Diff line change
`@@ -5452,6 +5452,7 @@ set_next_entity(struct cfs_rq cfs_rq, struct sched_entity se)`
`5452`	`5452`	`}`
`5453`	`5453`
`5454`	`5454`	`update_stats_curr_start(cfs_rq, se);`
	`5455`	`+ SCHED_WARN_ON(cfs_rq->curr);`
`5455`	`5456`	`cfs_rq->curr = se;`
`5456`	`5457`
`5457`	`5458`	`/*`
`@@ -5513,6 +5514,7 @@ static void put_prev_entity(struct cfs_rq cfs_rq, struct sched_entity prev)`
`5513`	`5514`	`/* in !on_rq case, update occurred at dequeue */`
`5514`	`5515`	`update_load_avg(cfs_rq, prev, 0);`
`5515`	`5516`	`}`
	`5517`	`+ SCHED_WARN_ON(cfs_rq->curr != prev);`
`5516`	`5518`	`cfs_rq->curr = NULL;`
`5517`	`5519`	`}`
`5518`	`5520`