Commit-ID: a731ebe6f17bff9e7ca12ef227f9da4d5bdf8425 Gitweb: http://git.kernel.org/tip/a731ebe6f17bff9e7ca12ef227f9da4d5bdf8425 Author: Peter Zijlstra <[email protected]> AuthorDate: Wed, 6 Sep 2017 12:51:31 +0200 Committer: Ingo Molnar <[email protected]> CommitDate: Thu, 7 Sep 2017 09:29:31 +0200
sched/fair: Fix wake_affine_llc() balancing rules Chris Wilson reported that the SMT balance rules got the +1 on the wrong side, resulting in a bias towards the current LLC; which the load-balancer would then try and undo. Reported-by: Chris Wilson <[email protected]> Tested-by: Chris Wilson <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Mike Galbraith <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Fixes: 90001d67be2f ("sched/fair: Fix wake_affine() for !NUMA_BALANCING") Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- kernel/sched/fair.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 8d58687..9dd2ce1 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -5435,7 +5435,7 @@ wake_affine_llc(struct sched_domain *sd, struct task_struct *p, return false; /* if this cache has capacity, come here */ - if (this_stats.has_capacity && this_stats.nr_running < prev_stats.nr_running+1) + if (this_stats.has_capacity && this_stats.nr_running+1 < prev_stats.nr_running) return true; /*
