From: Jiang Biao <benbji...@tencent.com>
delta in update_stats_wait_end() might be negative, which would
make following statistics go wrong.
Add protection for delta of wait time, like what have been done in
update_stats_enqueue_sleeper() for deltas of sleep/block time.
Signed-off-by: Jiang Biao <benbji...@tencent.com>
---
kernel/sched/fair.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index c0374c1152e0..ac950ac950bc 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -917,6 +917,9 @@ update_stats_wait_end(struct cfs_rq *cfs_rq, struct
sched_entity *se)
delta = rq_clock(rq_of(cfs_rq)) -
schedstat_val(se->statistics.wait_start);
+ if ((s64)delta < 0)
+ delta = 0;
+
if (entity_is_task(se)) {
p = task_of(se);
if (task_on_rq_migrating(p)) {
--
2.21.0
