From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752668AbbJMIH2 (ORCPT ); Tue, 13 Oct 2015 04:07:28 -0400 Received: from casper.infradead.org ([85.118.1.10]:45859 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752092AbbJMIHU (ORCPT ); Tue, 13 Oct 2015 04:07:20 -0400 Date: Tue, 13 Oct 2015 10:07:16 +0200 From: Peter Zijlstra To: Yuyang Du Cc: Mike Galbraith , linux-kernel@vger.kernel.org Subject: Re: 4.3 group scheduling regression Message-ID: <20151013080716.GQ3604@twins.programming.kicks-ass.net> References: <1444530318.3363.40.camel@gmail.com> <1444585321.4169.18.camel@gmail.com> <20151012072344.GM3604@twins.programming.kicks-ass.net> <1444635897.3425.19.camel@gmail.com> <20151012080407.GJ3816@twins.programming.kicks-ass.net> <20151012005351.GJ11102@intel.com> <20151012091206.GK3816@twins.programming.kicks-ass.net> <20151012021230.GK11102@intel.com> <20151012114723.GL3816@twins.programming.kicks-ass.net> <20151012193247.GL11102@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20151012193247.GL11102@intel.com> User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Oct 13, 2015 at 03:32:47AM +0800, Yuyang Du wrote: > On Mon, Oct 12, 2015 at 01:47:23PM +0200, Peter Zijlstra wrote: > > > > Also, should we do the below? At this point se->on_rq is still 0 so > > reweight_entity() will not update (dequeue/enqueue) the accounting, but > > we'll have just accounted the 'old' load.weight. > > > > Doing it this way around we'll first update the weight and then account > > it, which seems more accurate. > > I think the original looks ok. > > The account_entity_enqueue() adds child entity's load.weight to parent's load: > > update_load_add(&cfs_rq->load, se->load.weight) > > Then recalculate the shares. > > Then reweight_entity() resets the parent entity's load.weight. Yes, some days I should just not be allowed near a keyboard :)