From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752978AbeDKKxg (ORCPT ); Wed, 11 Apr 2018 06:53:36 -0400 Received: from merlin.infradead.org ([205.233.59.134]:45554 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752806AbeDKKxe (ORCPT ); Wed, 11 Apr 2018 06:53:34 -0400 Date: Wed, 11 Apr 2018 12:53:29 +0200 From: Peter Zijlstra To: Morten Rasmussen Cc: mingo@redhat.com, valentin.schneider@arm.com, dietmar.eggemann@arm.com, vincent.guittot@linaro.org, gaku.inami.xh@renesas.com, linux-kernel@vger.kernel.org Subject: Re: [PATCHv2 3/7] sched/fair: Consider misfit tasks when load-balancing Message-ID: <20180411105329.GI4043@hirez.programming.kicks-ass.net> References: <1521125224-15434-1-git-send-email-morten.rasmussen@arm.com> <1521125224-15434-4-git-send-email-morten.rasmussen@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1521125224-15434-4-git-send-email-morten.rasmussen@arm.com> User-Agent: Mutt/1.9.3 (2018-01-21) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Mar 15, 2018 at 02:47:00PM +0000, Morten Rasmussen wrote: > + /* > + * Don't try to pull misfit tasks we can't help. > + */ > + if (sgs->group_type == group_misfit_task && > + (!group_smaller_cpu_capacity(sg, sds->local) || > + !group_has_capacity(env, &sds->local_stat))) > + return false; > + I think that has the same 'problem' as last time, right? Since group_smaller_cpu_capacity() is affected by RT/IRQ pressure. We should have a comment stating this and preferably explaining why that is ok.