lkml.org 
[lkml]   [2021]   [Jan]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] sched/fair: add protection for delta of wait time
Date
From: Jiang Biao <benbjiang@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 <benbjiang@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
\
 
 \ /
  Last update: 2021-01-17 13:33    [W:0.088 / U:0.072 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site