From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753233Ab1GUS2g (ORCPT ); Thu, 21 Jul 2011 14:28:36 -0400 Received: from hera.kernel.org ([140.211.167.34]:49841 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752515Ab1GUS2e (ORCPT ); Thu, 21 Jul 2011 14:28:34 -0400 Date: Thu, 21 Jul 2011 18:28:25 GMT From: tip-bot for Paul Turner Message-ID: Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@redhat.com, a.p.zijlstra@chello.nl, pjt@google.com, tglx@linutronix.de, mingo@elte.hu Reply-To: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, a.p.zijlstra@chello.nl, pjt@google.com, tglx@linutronix.de, mingo@elte.hu In-Reply-To: <20110707053059.797714697@google.com> References: <20110707053059.797714697@google.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:sched/core] sched: Don't update shares twice on on_rq parent Git-Commit-ID: 9598c82dcacadc3b9daa8170613fd054c6124d30 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.3 (hera.kernel.org [127.0.0.1]); Thu, 21 Jul 2011 18:28:25 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 9598c82dcacadc3b9daa8170613fd054c6124d30 Gitweb: http://git.kernel.org/tip/9598c82dcacadc3b9daa8170613fd054c6124d30 Author: Paul Turner AuthorDate: Wed, 6 Jul 2011 22:30:37 -0700 Committer: Ingo Molnar CommitDate: Thu, 21 Jul 2011 18:01:44 +0200 sched: Don't update shares twice on on_rq parent In dequeue_task_fair() we bail on dequeue when we encounter a parenting entity with additional weight. However, we perform a double shares update on this entity as we continue the shares update traversal from this point, despite dequeue_entity() having already updated its queuing cfs_rq. Avoid this by starting from the parent when we resume. Signed-off-by: Paul Turner Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20110707053059.797714697@google.com Signed-off-by: Ingo Molnar --- kernel/sched_fair.c | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-) diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index f88720b..6cdff84 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c @@ -1370,6 +1370,9 @@ static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags) */ if (task_sleep && parent_entity(se)) set_next_buddy(parent_entity(se)); + + /* avoid re-evaluating load for this entity */ + se = parent_entity(se); break; } flags |= DEQUEUE_SLEEP;