From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757629Ab1KKV0M (ORCPT ); Fri, 11 Nov 2011 16:26:12 -0500 Received: from mail-gx0-f174.google.com ([209.85.161.174]:51116 "EHLO mail-gx0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752300Ab1KKV0J (ORCPT ); Fri, 11 Nov 2011 16:26:09 -0500 Message-ID: <4EBD92ED.4050701@google.com> Date: Fri, 11 Nov 2011 13:26:05 -0800 From: Paul Turner User-Agent: Mozilla/5.0 (X11; Linux i686 on x86_64; rv:7.0.1) Gecko/20110929 Thunderbird/7.0.1 MIME-Version: 1.0 Newsgroups: gmane.linux.kernel,gmane.linux.openvz.devel To: Andrew Vagin CC: Ingo Molnar , Peter Zijlstra , linux-kernel@vger.kernel.org, devel@openvz.org Subject: Re: [PATCH] sched: don't call task_group() many times in set_task_rq() References: <1321020240-3874331-1-git-send-email-avagin@openvz.org> In-Reply-To: <1321020240-3874331-1-git-send-email-avagin@openvz.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/11/2011 06:04 AM, Andrew Vagin wrote: > It improves perfomance, especially if autogroup enabled. > > The size of set_task_rq() was 0x180 and now it is 0xa0. A slightly more verbose commit message would be helpful here. > > Signed-off-by: Andrew Vagin Signed-off-by: Paul Turner > --- > kernel/sched.c | 12 ++++++++---- > 1 files changed, 8 insertions(+), 4 deletions(-) > > diff --git a/kernel/sched.c b/kernel/sched.c > index d87c6e5..a740eec 100644 > --- a/kernel/sched.c > +++ b/kernel/sched.c > @@ -766,14 +766,18 @@ static inline struct task_group *task_group(struct task_struct *p) > /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */ > static inline void set_task_rq(struct task_struct *p, unsigned int cpu) > { > +#if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED) > + struct task_group *tg = task_group(p); > +#endif > + > #ifdef CONFIG_FAIR_GROUP_SCHED > - p->se.cfs_rq = task_group(p)->cfs_rq[cpu]; > - p->se.parent = task_group(p)->se[cpu]; > + p->se.cfs_rq = tg->cfs_rq[cpu]; > + p->se.parent = tg->se[cpu]; > #endif > > #ifdef CONFIG_RT_GROUP_SCHED > - p->rt.rt_rq = task_group(p)->rt_rq[cpu]; > - p->rt.parent = task_group(p)->rt_se[cpu]; > + p->rt.rt_rq = tg->rt_rq[cpu]; > + p->rt.parent = tg->rt_se[cpu]; > #endif > } >