From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753379AbaHLOxt (ORCPT ); Tue, 12 Aug 2014 10:53:49 -0400 Received: from terminus.zytor.com ([198.137.202.10]:37018 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753050AbaHLOxq (ORCPT ); Tue, 12 Aug 2014 10:53:46 -0400 Date: Tue, 12 Aug 2014 07:52:10 -0700 From: tip-bot for Peter Zijlstra Message-ID: Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@kernel.org, torvalds@linux-foundation.org, peterz@infradead.org, riel@redhat.com, vincent.guittot@linaro.org, tglx@linutronix.de Reply-To: mingo@kernel.org, hpa@zytor.com, linux-kernel@vger.kernel.org, torvalds@linux-foundation.org, peterz@infradead.org, riel@redhat.com, vincent.guittot@linaro.org, tglx@linutronix.de In-Reply-To: <20140729152631.GW12054@laptop.lan> References: <20140729152631.GW12054@laptop.lan> To: linux-tip-commits@vger.kernel.org Subject: [tip:sched/core] sched/fair: Make calculate_imbalance() independent Git-Commit-ID: 743cb1ff191f00fee653212bdbcee1e56086d6ce X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 743cb1ff191f00fee653212bdbcee1e56086d6ce Gitweb: http://git.kernel.org/tip/743cb1ff191f00fee653212bdbcee1e56086d6ce Author: Peter Zijlstra AuthorDate: Tue, 29 Jul 2014 17:00:21 +0200 Committer: Ingo Molnar CommitDate: Tue, 12 Aug 2014 12:48:18 +0200 sched/fair: Make calculate_imbalance() independent Rik noticed that calculate_imbalance() relies on update_sd_pick_busiest() to guarantee that busiest->sum_nr_running > busiest->group_capacity_factor. Break this implicit assumption (with the intent of not providing it anymore) by having calculat_imbalance() verify it and not rely on others. Reported-by: Rik van Riel Signed-off-by: Peter Zijlstra Acked-by: Vincent Guittot Cc: Linus Torvalds Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/r/20140729152631.GW12054@laptop.lan Signed-off-by: Ingo Molnar --- 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 bfa3c86..e9477e6 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -6248,7 +6248,7 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s return fix_small_imbalance(env, sds); } - if (!busiest->group_imb) { + if (busiest->sum_nr_running > busiest->group_capacity_factor) { /* * Don't want to pull so many tasks that a group would go idle. * Except of course for the group_imb case, since then we might