Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932665AbaJUN33 (ORCPT ); Tue, 21 Oct 2014 09:29:29 -0400 Received: from service87.mimecast.com ([91.220.42.44]:49217 "EHLO service87.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932471AbaJUN32 convert rfc822-to-8bit (ORCPT ); Tue, 21 Oct 2014 09:29:28 -0400 Message-ID: <54465FB6.1060800@arm.com> Date: Tue, 21 Oct 2014 14:29:26 +0100 From: Juri Lelli User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.2.0 MIME-Version: 1.0 To: Wanpeng Li , Wanpeng Li , Ingo Molnar , Peter Zijlstra CC: "linux-kernel@vger.kernel.org" Subject: Re: [PATCH 2/2] sched/deadline: don't need to balance during wakeup if wakee is pinned References: <1413253360-5318-1-git-send-email-wanpeng.li@linux.intel.com> <1413253360-5318-2-git-send-email-wanpeng.li@linux.intel.com> <54464F59.3000100@gmail.com> In-Reply-To: <54464F59.3000100@gmail.com> X-OriginalArrivalTime: 21 Oct 2014 13:29:26.0147 (UTC) FILETIME=[08A96D30:01CFED33] X-MC-Unique: 114102114292604001 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 21/10/14 13:19, Wanpeng Li wrote: > Cc Juri, > > 于 10/14/14, 10:22 AM, Wanpeng Li 写道: >> Use nr_cpus_allowed to bail from select_task_rq() when only one cpu >> can be used, and saves some cycles for pinned tasks. >> >> Signed-off-by: Wanpeng Li >> --- >> kernel/sched/deadline.c | 3 +++ >> 1 file changed, 3 insertions(+) >> >> diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c >> index f46b7f1..5874bf8 100644 >> --- a/kernel/sched/deadline.c >> +++ b/kernel/sched/deadline.c >> @@ -914,6 +914,9 @@ select_task_rq_dl(struct task_struct *p, int cpu, int sd_flag, int flags) >> struct task_struct *curr; >> struct rq *rq; >> >> + if (p->nr_cpus_allowed == 1) >> + goto out; >> + >> if (sd_flag != SD_BALANCE_WAKE) >> goto out; >> Apart from the encoding of the resend, it looks good, thanks! Best, - Juri -- 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/