From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751461AbaJ0JnB (ORCPT ); Mon, 27 Oct 2014 05:43:01 -0400 Received: from szxga01-in.huawei.com ([119.145.14.64]:16056 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750939AbaJ0JnA (ORCPT ); Mon, 27 Oct 2014 05:43:00 -0400 Message-ID: <544E1348.4050100@huawei.com> Date: Mon, 27 Oct 2014 17:41:28 +0800 From: Yao Dongdong User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:17.0) Gecko/20130509 Thunderbird/17.0.6 MIME-Version: 1.0 To: Ingo Molnar , Peter Zijlstra CC: LKML , Srikar Dronamraju , Subject: [PATCH v2]sched:add check of shallowest_idle_cpu before search for least_loaded_cpu Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.110.51.36] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Idle cpu is idler than non-idle cpu, so we needn't search for least_loaded_cpu after we have found an idle cpu. Signed-off-by:yaodongdong@huawei.com Reviewed-by: Srikar Dronamraju --- kernel/sched/fair.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 0b069bf..2445a23 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -4446,7 +4446,7 @@ find_idlest_cpu(struct sched_group *group, struct task_struct *p, int this_cpu) latest_idle_timestamp = rq->idle_stamp; shallowest_idle_cpu = i; } - } else { + } else if (shallowest_idle_cpu == -1) { load = weighted_cpuload(i); if (load < min_load || (load == min_load && i == this_cpu)) { min_load = load; -- 1.8.0.1