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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 693A4C433EF for ; Thu, 14 Apr 2022 10:33:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241857AbiDNKf7 (ORCPT ); Thu, 14 Apr 2022 06:35:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41928 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239293AbiDNKfw (ORCPT ); Thu, 14 Apr 2022 06:35:52 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 8526C6D39B for ; Thu, 14 Apr 2022 03:33:27 -0700 (PDT) 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 A559A139F; Thu, 14 Apr 2022 03:33:27 -0700 (PDT) Received: from [192.168.178.6] (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 3B0413F5A1; Thu, 14 Apr 2022 03:33:27 -0700 (PDT) Message-ID: Date: Thu, 14 Apr 2022 12:33:06 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.5.0 From: Dietmar Eggemann Subject: Re: [PATCH] sched/fair: Revise comment about lb decision matrix To: Tao Zhou , linux-kernel@vger.kernel.org References: <20220403175946.7323-1-tao.zhou@linux.dev> Content-Language: en-US In-Reply-To: <20220403175946.7323-1-tao.zhou@linux.dev> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/04/2022 19:59, Tao Zhou wrote: > If busiest group type is group_misfit_task, the local > group type must be group_has_spare according to below > code in update_sd_pick_busiest(): > > if (sgs->group_type == group_misfit_task && > (!capacity_greater(capacity_of(env->dst_cpu), sg->sgc->max_capacity) || > sds->local_stat.group_type != group_has_spare)) > return false; > > group type imbalanced and overloaded and fully_busy are filtered in here. > misfit and asym are filtered before in update_sg_lb_stats(). > So, change the decision matrix to: > > busiest \ local has_spare fully_busy misfit asym imbalanced overloaded > has_spare nr_idle balanced N/A N/A balanced balanced > fully_busy nr_idle nr_idle N/A N/A balanced balanced > misfit_task force N/A N/A N/A *N/A* *N/A* > asym_packing force force N/A N/A force force > imbalanced force force N/A N/A force force > overloaded force force N/A N/A force avg_load > --- > kernel/sched/fair.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c > index 5146163bfabb..5765d96202c7 100644 > --- a/kernel/sched/fair.c > +++ b/kernel/sched/fair.c > @@ -9441,7 +9441,7 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s > * busiest \ local has_spare fully_busy misfit asym imbalanced overloaded > * has_spare nr_idle balanced N/A N/A balanced balanced > * fully_busy nr_idle nr_idle N/A N/A balanced balanced > - * misfit_task force N/A N/A N/A force force > + * misfit_task force N/A N/A N/A N/A N/A > * asym_packing force force N/A N/A force force > * imbalanced force force N/A N/A force force > * overloaded force force N/A N/A force avg_load You should put people you find in `./scripts/get_maintainer.pl kernel/sched/fair.c` on To/Cc to attract more attention. Otherwise, LGTM. Reviewed-by: Dietmar Eggemann