From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753357AbaHLOzX (ORCPT ); Tue, 12 Aug 2014 10:55:23 -0400 Received: from terminus.zytor.com ([198.137.202.10]:37016 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753174AbaHLOxo (ORCPT ); Tue, 12 Aug 2014 10:53:44 -0400 Date: Tue, 12 Aug 2014 07:52:39 -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: <20140729152705.GX12054@laptop.lan> References: <20140729152705.GX12054@laptop.lan> To: linux-tip-commits@vger.kernel.org Subject: [tip:sched/core] sched/fair: Allow calculate_imbalance() to move idle cpus Git-Commit-ID: 9a5d9ba6a3631d55c358fe1bdbaa162a97471a05 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: 9a5d9ba6a3631d55c358fe1bdbaa162a97471a05 Gitweb: http://git.kernel.org/tip/9a5d9ba6a3631d55c358fe1bdbaa162a97471a05 Author: Peter Zijlstra AuthorDate: Tue, 29 Jul 2014 17:15:11 +0200 Committer: Ingo Molnar CommitDate: Tue, 12 Aug 2014 12:48:20 +0200 sched/fair: Allow calculate_imbalance() to move idle cpus Allow calculate_imbalance() to 'create' idle cpus in the busiest group if there are idle cpus in the local group. Suggested-by: Rik van Riel Signed-off-by: Peter Zijlstra Acked-by: Vincent Guittot Cc: Linus Torvalds Link: http://lkml.kernel.org/r/20140729152705.GX12054@laptop.lan Signed-off-by: Ingo Molnar --- kernel/sched/fair.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 9437725..df1ed17 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -6273,12 +6273,11 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s return fix_small_imbalance(env, sds); } - if (busiest->group_type == group_overloaded) { - /* - * 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 - * have to drop below capacity to reach cpu-load equilibrium. - */ + /* + * If there aren't any idle cpus, avoid creating some. + */ + if (busiest->group_type == group_overloaded && + local->group_type == group_overloaded) { load_above_capacity = (busiest->sum_nr_running - busiest->group_capacity_factor);