From e90c8fe15a3bf93a23088bcf1a56a0fa391d4e50 Mon Sep 17 00:00:00 2001 From: Valentin Schneider Date: Wed, 4 Jul 2018 11:17:46 +0100 Subject: sched/fair: Wrap rq->rd->overload accesses with READ/WRITE_ONCE() This variable can be read and set locklessly within update_sd_lb_stats(). As such, READ/WRITE_ONCE() are added to make sure nothing terribly wrong can happen because of the compiler. Signed-off-by: Valentin Schneider Signed-off-by: Morten Rasmussen Signed-off-by: Peter Zijlstra (Intel) Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: dietmar.eggemann@arm.com Cc: gaku.inami.xh@renesas.com Cc: vincent.guittot@linaro.org Link: http://lkml.kernel.org/r/1530699470-29808-9-git-send-email-morten.rasmussen@arm.com Signed-off-by: Ingo Molnar --- kernel/sched/sched.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'kernel/sched/sched.h') diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 4d181478c5b8..938063639793 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -1697,8 +1697,8 @@ static inline void add_nr_running(struct rq *rq, unsigned count) if (prev_nr < 2 && rq->nr_running >= 2) { #ifdef CONFIG_SMP - if (!rq->rd->overload) - rq->rd->overload = 1; + if (!READ_ONCE(rq->rd->overload)) + WRITE_ONCE(rq->rd->overload, 1); #endif } -- cgit v1.2.3-70-g09d2