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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 C9827C34026 for ; Tue, 18 Feb 2020 12:38:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A5F7521D56 for ; Tue, 18 Feb 2020 12:38:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726623AbgBRMiX (ORCPT ); Tue, 18 Feb 2020 07:38:23 -0500 Received: from foss.arm.com ([217.140.110.172]:51344 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726363AbgBRMiX (ORCPT ); Tue, 18 Feb 2020 07:38:23 -0500 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 CE056328; Tue, 18 Feb 2020 04:38:22 -0800 (PST) Received: from [192.168.0.7] (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 08B1B3F6CF; Tue, 18 Feb 2020 04:38:20 -0800 (PST) Subject: Re: [PATCH v2 1/5] sched/fair: Reorder enqueue/dequeue_task_fair path To: Vincent Guittot , mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, linux-kernel@vger.kernel.org Cc: pauld@redhat.com, parth@linux.ibm.com, valentin.schneider@arm.com, hdanton@sina.com References: <20200214152729.6059-1-vincent.guittot@linaro.org> <20200214152729.6059-2-vincent.guittot@linaro.org> From: Dietmar Eggemann Message-ID: Date: Tue, 18 Feb 2020 13:37:37 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: <20200214152729.6059-2-vincent.guittot@linaro.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 14/02/2020 16:27, Vincent Guittot wrote: > The walk through the cgroup hierarchy during the enqueue/dequeue of a task > is split in 2 distinct parts for throttled cfs_rq without any added value > but making code less readable. > > Change the code ordering such that everything related to a cfs_rq > (throttled or not) will be done in the same loop. > > In addition, the same steps ordering is used when updating a cfs_rq: > - update_load_avg > - update_cfs_group > - update *h_nr_running Is this code change really necessary? You pay with two extra goto's. We still have the two for_each_sched_entity(se)'s because of 'if (se->on_rq); break;'. [...]