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 360E6C433EF for ; Fri, 15 Apr 2022 09:54:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1351921AbiDOJ5O (ORCPT ); Fri, 15 Apr 2022 05:57:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59396 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348693AbiDOJ5L (ORCPT ); Fri, 15 Apr 2022 05:57:11 -0400 Received: from out2.migadu.com (out2.migadu.com [IPv6:2001:41d0:2:aacc::]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9E6D46363 for ; Fri, 15 Apr 2022 02:54:41 -0700 (PDT) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1650016479; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=Id7F0bBZwbU+kl7Y3j+XMtZvdbjgCDi5TDTPOpN4GdU=; b=Zk4aoDHIpJJgbvB00NtqUzwl4Qhff2grUyVx5+Yb6YblUYbAS9Y8jo98SPFAHfUYkiZnS1 mivhOXdh2sQIViWYXw/UF0cmYKRSgXBWKRSJHFV5OdKDtLO10KSECKZqEc0M5SL7npyqtm l1sCbefWqNgc0GlM83W4uIOZTiykzg0= From: Tao Zhou To: LKML , Tao Zhou Cc: Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Daniel Bristot de Oliveira , Morten Rasmussen , Valentin Schneider Subject: [PATCH V1 RESEND]: sched/fair: Revise comment about lb decision matrix Date: Fri, 15 Apr 2022 17:55:04 +0800 Message-Id: <20220415095505.7765-1-tao.zhou@linux.dev> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: linux.dev Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 Fixes: 0b0695f2b34a ("sched/fair: Rework load_balance()") Reviewed-by: Dietmar Eggemann Signed-off-by: Tao Zhou --- v1 changelog: (1) Send to MAINTAINERS/REVIEWS get from `./scripts/get_maintainer.pl` suggested by Dietmar Eggemann. (2) Based on v5.18-rc2 v1->v2 changelog: (1) Add Reviewed-by from Vincent Guittot. (2) This behavior has changed with cad68e552e77 ("sched/fair: Consider misfit tasks when load-balancing") and the matrix has not changed. Add the related people of commit cad68e552e77 to the cc list. 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 d4bd299d67ab..b8c67e7c8cf3 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -9495,7 +9495,7 @@ 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 -- 2.35.2