Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754327Ab3FELHK (ORCPT ); Wed, 5 Jun 2013 07:07:10 -0400 Received: from merlin.infradead.org ([205.233.59.134]:48814 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752290Ab3FELHG (ORCPT ); Wed, 5 Jun 2013 07:07:06 -0400 Date: Wed, 5 Jun 2013 13:06:57 +0200 From: Peter Zijlstra To: Michael Wang Cc: LKML , Ingo Molnar , Paul Turner Subject: Re: [PATCH v2 1/3] sched: don't repeat the initialization in sched_init() Message-ID: <20130605110657.GZ8923@twins.programming.kicks-ass.net> References: <51AD87A8.6080608@linux.vnet.ibm.com> <51AD87D0.7020300@linux.vnet.ibm.com> <51AEA152.1050609@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <51AEA152.1050609@linux.vnet.ibm.com> User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2070 Lines: 57 On Wed, Jun 05, 2013 at 10:24:18AM +0800, Michael Wang wrote: > v2: > Move comments back before init_tg_cfs_entry(). (Thanks for the notify from pjt) > > In sched_init(), there is no need to initialize 'root_task_group.shares' and > 'root_task_group.cfs_bandwidth' repeatedly. > > CC: Paul Tuner > CC: Ingo Molnar > CC: Peter Zijlstra > Signed-off-by: Michael Wang > --- > kernel/sched/core.c | 7 +++++-- > 1 files changed, 5 insertions(+), 2 deletions(-) > > diff --git a/kernel/sched/core.c b/kernel/sched/core.c > index 58453b8..96f69da 100644 > --- a/kernel/sched/core.c > +++ b/kernel/sched/core.c > @@ -6955,6 +6955,11 @@ void __init sched_init(void) > > #endif /* CONFIG_CGROUP_SCHED */ > > +#ifdef CONFIG_FAIR_GROUP_SCHED > + root_task_group.shares = ROOT_TASK_GROUP_LOAD; > + init_cfs_bandwidth(&root_task_group.cfs_bandwidth); > +#endif > + > for_each_possible_cpu(i) { > struct rq *rq; > > @@ -6966,7 +6971,6 @@ void __init sched_init(void) > init_cfs_rq(&rq->cfs); > init_rt_rq(&rq->rt, rq); > #ifdef CONFIG_FAIR_GROUP_SCHED > - root_task_group.shares = ROOT_TASK_GROUP_LOAD; > INIT_LIST_HEAD(&rq->leaf_cfs_rq_list); > /* > * How much cpu bandwidth does root_task_group get? > @@ -6987,7 +6991,6 @@ void __init sched_init(void) > * We achieve this by letting root_task_group's tasks sit > * directly in rq->cfs (i.e root_task_group->se[] = NULL). > */ > - init_cfs_bandwidth(&root_task_group.cfs_bandwidth); > init_tg_cfs_entry(&root_task_group, &rq->cfs, NULL, i, NULL); > #endif /* CONFIG_FAIR_GROUP_SCHED */ I would actually like a patch reducing the #ifdef forest there, not adding to it. There's no actual harm in doing the initialization mutliple times, right? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/