From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753299Ab1AZMKj (ORCPT ); Wed, 26 Jan 2011 07:10:39 -0500 Received: from hera.kernel.org ([140.211.167.34]:39678 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753184Ab1AZMKh (ORCPT ); Wed, 26 Jan 2011 07:10:37 -0500 Date: Wed, 26 Jan 2011 12:10:13 GMT From: tip-bot for Paul Turner 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: <20110122044851.825284940@google.com> References: <20110122044851.825284940@google.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:sched/core] sched: Fix/remove redundant cfs_rq checks Message-ID: Git-Commit-ID: b815f1963e47b9b69bb17e0588bd5af5b1114ae0 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]); Wed, 26 Jan 2011 12:10:13 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: b815f1963e47b9b69bb17e0588bd5af5b1114ae0 Gitweb: http://git.kernel.org/tip/b815f1963e47b9b69bb17e0588bd5af5b1114ae0 Author: Paul Turner AuthorDate: Fri, 21 Jan 2011 20:45:00 -0800 Committer: Ingo Molnar CommitDate: Wed, 26 Jan 2011 12:31:02 +0100 sched: Fix/remove redundant cfs_rq checks Since updates are against an entity's queuing cfs_rq it's not possible to enter update_cfs_{shares,load} with a NULL cfs_rq. (Indeed, update_cfs_load would crash prior to the check if we did anyway since we load is examined during the initializers). Also, in the update_cfs_load case there's no point in maintaining averages for rq->cfs_rq since we don't perform shares distribution at that level -- NULL check is replaced accordingly. Thanks to Dan Carpenter for pointing out the deference before NULL check. Signed-off-by: Paul Turner Signed-off-by: Peter Zijlstra LKML-Reference: <20110122044851.825284940@google.com> Signed-off-by: Ingo Molnar --- kernel/sched_fair.c | 5 +---- 1 files changed, 1 insertions(+), 4 deletions(-) diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index ccecfec..1997383 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c @@ -722,7 +722,7 @@ static void update_cfs_load(struct cfs_rq *cfs_rq, int global_update) u64 now, delta; unsigned long load = cfs_rq->load.weight; - if (!cfs_rq) + if (cfs_rq->tg == &root_task_group) return; now = rq_of(cfs_rq)->clock; @@ -830,9 +830,6 @@ static void update_cfs_shares(struct cfs_rq *cfs_rq, long weight_delta) struct sched_entity *se; long shares; - if (!cfs_rq) - return; - tg = cfs_rq->tg; se = tg->se[cpu_of(rq_of(cfs_rq))]; if (!se)