From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932212Ab2DKQOr (ORCPT ); Wed, 11 Apr 2012 12:14:47 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:25743 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759752Ab2DKQOq (ORCPT ); Wed, 11 Apr 2012 12:14:46 -0400 X-Authority-Analysis: v=2.0 cv=Z8Fu7QtA c=1 sm=0 a=ZycB6UtQUfgMyuk2+PxD7w==:17 a=XQbtiDEiEegA:10 a=TWBfIqSxIMQA:10 a=5SG0PmZfjMsA:10 a=Q9fys5e9bTEA:10 a=rcl-2mVQVphY_GoDj8kA:9 a=PUjeQqilurYA:10 a=ZycB6UtQUfgMyuk2+PxD7w==:117 X-Cloudmark-Score: 0 X-Originating-IP: 74.67.80.29 Message-ID: <1334160884.23924.260.camel@gandalf.stny.rr.com> Subject: Re: [PATCH 06/16] sched: SCHED_DEADLINE push and pull logic From: Steven Rostedt To: Juri Lelli Cc: peterz@infradead.org, tglx@linutronix.de, mingo@redhat.com, oleg@redhat.com, fweisbec@gmail.com, darren@dvhart.com, johan.eker@ericsson.com, p.faure@akatech.ch, linux-kernel@vger.kernel.org, claudio@evidence.eu.com, michael@amarulasolutions.com, fchecconi@gmail.com, tommaso.cucinotta@sssup.it, nicola.manica@disi.unitn.it, luca.abeni@unitn.it, dhaval.giani@gmail.com, hgu1972@gmail.com, paulmck@linux.vnet.ibm.com, raistlin@linux.it, insop.song@ericsson.com, liming.wang@windriver.com Date: Wed, 11 Apr 2012 12:14:44 -0400 In-Reply-To: <1333696481-3433-7-git-send-email-juri.lelli@gmail.com> References: <1333696481-3433-1-git-send-email-juri.lelli@gmail.com> <1333696481-3433-7-git-send-email-juri.lelli@gmail.com> Content-Type: text/plain; charset="ISO-8859-15" X-Mailer: Evolution 3.2.2-1 Content-Transfer-Encoding: 7bit Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2012-04-06 at 09:14 +0200, Juri Lelli wrote: > +static int latest_cpu_find(struct cpumask *span, > + struct task_struct *task, > + struct cpumask *later_mask) > { > + const struct sched_dl_entity *dl_se = &task->dl; > + int cpu, found = -1, best = 0; > + u64 max_dl = 0; > + > + for_each_cpu(cpu, span) { > + struct rq *rq = cpu_rq(cpu); > + struct dl_rq *dl_rq = &rq->dl; > + > + if (cpumask_test_cpu(cpu, &task->cpus_allowed) && > + (!dl_rq->dl_nr_running || dl_time_before(dl_se->deadline, > + dl_rq->earliest_dl.curr))) { > + if (later_mask) > + cpumask_set_cpu(cpu, later_mask); > + if (!best && !dl_rq->dl_nr_running) { I hate to say this (and I also have yet to look at the patches after this) but we should really take into account the RT tasks. It would suck to preempt a normal RT task when a non RT task is running on another CPU. -- Steve > + best = 1; > + found = cpu; > + } else if (!best && > + dl_time_before(max_dl, > + dl_rq->earliest_dl.curr)) { > + max_dl = dl_rq->earliest_dl.curr; > + found = cpu; > + } > + } else if (later_mask) > + cpumask_clear_cpu(cpu, later_mask); > + } > + > + return found; > +}