From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5FBAEC433DF for ; Tue, 13 Oct 2020 13:20:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F421222DCC for ; Tue, 13 Oct 2020 13:20:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728532AbgJMNUi (ORCPT ); Tue, 13 Oct 2020 09:20:38 -0400 Received: from foss.arm.com ([217.140.110.172]:59874 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726648AbgJMNUi (ORCPT ); Tue, 13 Oct 2020 09:20:38 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id E41491FB; Tue, 13 Oct 2020 06:20:37 -0700 (PDT) Received: from e113632-lin (e113632-lin.cambridge.arm.com [10.1.194.46]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id C38F83F719; Tue, 13 Oct 2020 06:20:35 -0700 (PDT) References: <20201005145717.346020688@infradead.org> <20201005150921.960169379@infradead.org> <20201012113657.GV2628@hirez.programming.kicks-ass.net> User-agent: mu4e 0.9.17; emacs 26.3 From: Valentin Schneider To: Tao Zhou Cc: Peter Zijlstra , tglx@linutronix.de, mingo@kernel.org, linux-kernel@vger.kernel.org, bigeasy@linutronix.de, qais.yousef@arm.com, swood@redhat.com, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, vincent.donnefort@arm.com, tj@kernel.org Subject: Re: [PATCH -v2 10/17] sched: Fix migrate_disable() vs set_cpus_allowed_ptr() In-reply-to: Date: Tue, 13 Oct 2020 14:20:29 +0100 Message-ID: MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/10/20 19:25, Tao Zhou wrote: > Hi Peter, > @@ -1989,7 +1994,24 @@ static int affine_move_task(struct rq *rq, struct rq_flags *rf, > }; > bool complete = false; > > - /* Can the task run on the task's current CPU? If so, we're done */ > + /* > + * Can the task run on the task's current CPU ? If so, we're done. > + * One scenario can happen here. Consider task T running on CPU P0: > + * > + * P0 P1 p2 That naming convention weirds me out, and I'm the one who wrote that... How about: https://gitlab.arm.com/linux-arm/linux-vs/-/commit/b30f50c7b2dd1ef70598bbe1a2a90934d894b861 I also have an extra goodie: https://gitlab.arm.com/linux-arm/linux-vs/-/commits/mainline/review/migrate_disable_peterz_v2_extras/ The whole thing can be cloned via git@git.gitlab.arm.com:linux-arm/linux-vs.git -b mainline/review/migrate_disable_peterz_v2_extras (I can send those as replies to patch 0 if that helps)