From: Tao Zhou Date: Thu, 19 Mar 2020 03:39:20 +0000 (+0800) Subject: sched/fair: Fix condition of avg_load calculation X-Git-Tag: v5.5.18~209 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1b8d18aa12790b7fd08e22bceae1752c1a0c4288;p=thirdparty%2Fkernel%2Fstable.git sched/fair: Fix condition of avg_load calculation [ Upstream commit 6c8116c914b65be5e4d6f66d69c8142eb0648c22 ] In update_sg_wakeup_stats(), the comment says: Computing avg_load makes sense only when group is fully busy or overloaded. But, the code below this comment does not check like this. From reading the code about avg_load in other functions, I confirm that avg_load should be calculated in fully busy or overloaded case. The comment is correct and the checking condition is wrong. So, change that condition. Fixes: 57abff067a08 ("sched/fair: Rework find_idlest_group()") Signed-off-by: Tao Zhou Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Vincent Guittot Acked-by: Mel Gorman Link: https://lkml.kernel.org/r/Message-ID: Signed-off-by: Sasha Levin --- diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 0ff2f43ac9cd7..1f5ea23c752be 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -8323,7 +8323,8 @@ static inline void update_sg_wakeup_stats(struct sched_domain *sd, * Computing avg_load makes sense only when group is fully busy or * overloaded */ - if (sgs->group_type < group_fully_busy) + if (sgs->group_type == group_fully_busy || + sgs->group_type == group_overloaded) sgs->avg_load = (sgs->group_load * SCHED_CAPACITY_SCALE) / sgs->group_capacity; }