Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932792AbaJUNmm (ORCPT ); Tue, 21 Oct 2014 09:42:42 -0400 Received: from service87.mimecast.com ([91.220.42.44]:35211 "EHLO service87.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932510AbaJUNml convert rfc822-to-8bit (ORCPT ); Tue, 21 Oct 2014 09:42:41 -0400 Message-ID: <544662CD.5070501@arm.com> Date: Tue, 21 Oct 2014 14:42:37 +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> <54465FB6.1060800@arm.com> <5446620E.4020700@gmail.com> In-Reply-To: <5446620E.4020700@gmail.com> X-OriginalArrivalTime: 21 Oct 2014 13:42:37.0392 (UTC) FILETIME=[E047D500:01CFED34] X-MC-Unique: 114102114423702601 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 On 21/10/14 14:39, Wanpeng Li wrote: > Hi Juri, > > 于 10/21/14, 9:29 PM, Juri Lelli 写道: >> 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! > > What's your meaning of resend? Do you mean this one? Nope. I just meant that I received your "Cc Juri" encoded as Chinese Simplified. But, I guess the original lkml patch looks good. Sorry for the confusion :). Best, - Juri > > https://lkml.org/lkml/2014/10/10/425 > > I'm afraid they are different patches. > > Regards, > Wanpeng Li > >> >> 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/