From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 25449C433B4 for ; Wed, 12 May 2021 12:51:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E9CAE613CD for ; Wed, 12 May 2021 12:51:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231127AbhELMwm (ORCPT ); Wed, 12 May 2021 08:52:42 -0400 Received: from mx2.suse.de ([195.135.220.15]:51810 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230472AbhELMwl (ORCPT ); Wed, 12 May 2021 08:52:41 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 51B38AE27; Wed, 12 May 2021 12:51:32 +0000 (UTC) Date: Wed, 12 May 2021 13:51:29 +0100 From: Mel Gorman To: Peter Zijlstra Cc: tglx@linutronix.de, mingo@kernel.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, bristot@redhat.com, bsingharora@gmail.com, pbonzini@redhat.com, maz@kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, riel@surriel.com, hannes@cmpxchg.org Subject: Re: [PATCH 3/6] sched: Simplify sched_info_on() Message-ID: <20210512125129.GI3672@suse.de> References: <20210505105940.190490250@infradead.org> <20210505111525.121458839@infradead.org> <20210512111040.GC3672@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Wed, May 12, 2021 at 01:32:03PM +0200, Peter Zijlstra wrote: > On Wed, May 12, 2021 at 12:10:40PM +0100, Mel Gorman wrote: > > As delta is !0 iff t->sched_info.last_queued, why not this? > > > > diff --git a/kernel/sched/stats.h b/kernel/sched/stats.h > > index 33ffd41935ba..37e33c0eeb7c 100644 > > --- a/kernel/sched/stats.h > > +++ b/kernel/sched/stats.h > > @@ -158,15 +158,14 @@ static inline void psi_sched_switch(struct task_struct *prev, > > */ > > static inline void sched_info_dequeue(struct rq *rq, struct task_struct *t) > > { > > - unsigned long long delta = 0; > > - > > if (t->sched_info.last_queued) { > > + unsigned long long delta; > > + > > delta = rq_clock(rq) - t->sched_info.last_queued; > > t->sched_info.last_queued = 0; > > + t->sched_info.run_delay += delta; > > + rq_sched_info_dequeue(rq, delta); > > } > > - t->sched_info.run_delay += delta; > > - > > - rq_sched_info_dequeue(rq, delta); > > } > > Right.. clearly I missed the obvious there.. Lemme go add another patch > on top of the lot. > > Something like this I suppose. > That works for me. -- Mel Gorman SUSE Labs