Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755555Ab3EIBYl (ORCPT ); Wed, 8 May 2013 21:24:41 -0400 Received: from mga14.intel.com ([143.182.124.37]:17677 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752817Ab3EIBYk (ORCPT ); Wed, 8 May 2013 21:24:40 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.87,638,1363158000"; d="scan'208";a="238854968" Message-ID: <518AFAC6.5010906@intel.com> Date: Thu, 09 May 2013 09:24:22 +0800 From: Alex Shi User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130329 Thunderbird/17.0.5 MIME-Version: 1.0 To: Paul Turner CC: Peter Zijlstra , Ingo Molnar , Thomas Gleixner , Andrew Morton , Borislav Petkov , Namhyung Kim , Mike Galbraith , Morten Rasmussen , Vincent Guittot , Preeti U Murthy , Viresh Kumar , LKML , Mel Gorman , Rik van Riel , Michael Wang Subject: Re: [PATCH v5 6/7] sched: consider runnable load average in move_tasks References: <1367804711-30308-1-git-send-email-alex.shi@intel.com> <1367804711-30308-7-git-send-email-alex.shi@intel.com> <20130506150428.GD15446@dyad.programming.kicks-ass.net> <51888E87.2090506@intel.com> <5189ACD2.1080105@intel.com> In-Reply-To: <5189ACD2.1080105@intel.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1707 Lines: 43 Paul, I am wondering if the following patch needed. The wakeuped migrated task will __synchronize_entity_decay(se); in migrate_task_fair, then it needs to set `se->avg.last_runnable_update -= (-se->avg.decay_count) << 20' before update_entity_load_avg, in order to avoid slept time is updated twice for se.avg.load_avg_contrib in both __syncchronize and update_entity_load_avg. but if the slept task is waked up from self cpu, it miss the last_runnable_update before update_entity_load_avg(se, 0, 1), so the slept time was used twice in both functions. Is that right? Regards Alex --- diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index a80ae94..1b49e97 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -1532,7 +1532,8 @@ static inline void enqueue_entity_load_avg(struct cfs_rq *cfs_rq, } wakeup = 0; } else { - __synchronize_entity_decay(se); + se->avg.last_runnable_update += __synchronize_entity_decay(se) + << 20; } /* migrated tasks did not contribute to our blocked load */ if (wakeup) { subtract_blocked_load_contrib(cfs_rq, se->avg.load_avg_contrib); update_entity_load_avg(se, 0, 1); } -- Thanks Alex -- 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/