From 0d10ab952e99f3e9f374898e93f45452b81e5711 Mon Sep 17 00:00:00 2001 From: Brendan Jackman Date: Thu, 5 Oct 2017 12:45:14 +0100 Subject: [PATCH] sched/fair: Fix find_idlest_group() when local group is not allowed When the local group is not allowed we do not modify this_*_load from their initial value of 0. That means that the load checks at the end of find_idlest_group cause us to incorrectly return NULL. Fixing the initial values to ULONG_MAX means we will instead return the idlest remote group in that case. Signed-off-by: Brendan Jackman Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Vincent Guittot Reviewed-by: Josef Bacik Cc: Dietmar Eggemann Cc: Josef Bacik Cc: Linus Torvalds Cc: Mike Galbraith Cc: Morten Rasmussen Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20171005114516.18617-4-brendan.jackman@arm.com Signed-off-by: Ingo Molnar --- kernel/sched/fair.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index bdd28fbad7a3..cca1835efa7b 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -5737,8 +5737,9 @@ find_idlest_group(struct sched_domain *sd, struct task_struct *p, { struct sched_group *idlest = NULL, *group = sd->groups; struct sched_group *most_spare_sg = NULL; - unsigned long min_runnable_load = ULONG_MAX, this_runnable_load = 0; - unsigned long min_avg_load = ULONG_MAX, this_avg_load = 0; + unsigned long min_runnable_load = ULONG_MAX; + unsigned long this_runnable_load = ULONG_MAX; + unsigned long min_avg_load = ULONG_MAX, this_avg_load = ULONG_MAX; unsigned long most_spare = 0, this_spare = 0; int load_idx = sd->forkexec_idx; int imbalance_scale = 100 + (sd->imbalance_pct-100)/2; -- 2.39.5