From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759561Ab3BMOPJ (ORCPT ); Wed, 13 Feb 2013 09:15:09 -0500 Received: from mailhost-y5-m4.nerim-networks.com ([78.40.49.242]:28504 "EHLO smtp-delay2.nerim.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1759384Ab3BMOPH (ORCPT ); Wed, 13 Feb 2013 09:15:07 -0500 X-Greylist: delayed 360 seconds by postgrey-1.27 at vger.kernel.org; Wed, 13 Feb 2013 09:15:07 EST Date: Wed, 13 Feb 2013 15:08:43 +0100 From: Damien Wyart To: Vincent Guittot Cc: linux-kernel@vger.kernel.org, linaro-dev@lists.linaro.org, peterz@infradead.org, mingo@kernel.org, Frederic Weisbecker Subject: Re: [PATCH] sched: fix env->src_cpu for active migration Message-ID: <20130213140843.GA21308@brouette> References: <1360675195-4017-1-git-send-email-vincent.guittot@linaro.org> <20130213061853.GA4043@brouette> <20130213092154.GA4481@brouette> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Vincent Guittot [2013-02-13 13:08]: > Damien, > Regarding your sched_domain config and especially the flags field, you > should not be impacted by my patch because > - need_active_balance is the only new place that use env->src_cpu in > the load_balance function > - and your machine will never test the condition: "env->src_cpu > > env->dst_cpu" in need_active_balance because SD_ASYM_PACKING is not > set in your config > Have you tested the patch with others that could have modified the > load_balance function ? Yes, sorry, I should have been more precise in my initial report: your patch was not applied on top of vanilla 3.8-rc7, but a few other patches were also present. Seems the ones impacting load_balance are from Frederic's nohz work (http://git.kernel.org/?p=linux/kernel/git/frederic/linux-dynticks.git;a=shortlog;h=refs/heads/3.8-rc6-nohz4) The patches from there modifying load_balance are: - "sched: Update nohz rq clock before searching busiest group on load balancing" - "sched: Update clock of nohz busiest rq before balancing" In this test, I did not use any kernel parameter related to this patchset (full_nohz, etc.). I am adding Frederic in Cc, not sure if the breakage is to be investigated on your side or his... Thanks for your explanations, -- Damien