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=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 0A5A9C433E0 for ; Thu, 28 Jan 2021 18:44:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B2D4F64E21 for ; Thu, 28 Jan 2021 18:44:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232382AbhA1SnL (ORCPT ); Thu, 28 Jan 2021 13:43:11 -0500 Received: from foss.arm.com ([217.140.110.172]:37444 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232147AbhA1SfH (ORCPT ); Thu, 28 Jan 2021 13:35:07 -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 2024B1480; Thu, 28 Jan 2021 10:32:14 -0800 (PST) Received: from e113632-lin.cambridge.arm.com (e113632-lin.cambridge.arm.com [10.1.194.46]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id A6A153F719; Thu, 28 Jan 2021 10:32:12 -0800 (PST) From: Valentin Schneider To: linux-kernel@vger.kernel.org Cc: Peter Zijlstra , Ingo Molnar , Vincent Guittot , Dietmar Eggemann , Morten Rasmussen , Qais Yousef , Quentin Perret , Pavan Kondeti , Rik van Riel Subject: [PATCH 5/8] sched/fair: Make check_misfit_status() only compare dynamic capacities Date: Thu, 28 Jan 2021 18:31:38 +0000 Message-Id: <20210128183141.28097-6-valentin.schneider@arm.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210128183141.28097-1-valentin.schneider@arm.com> References: <20210128183141.28097-1-valentin.schneider@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org check_misfit_status() checks for both capacity pressure & available CPUs with higher capacity. Now that we have a sane(ish) capacity comparison margin which is used throughout load-balance, this can be condensed into a single check: capacity_greater(, ); This has the added benefit of returning false if the misfit task CPU's is heavily pressured, but there are no better candidates for migration. Signed-off-by: Valentin Schneider --- kernel/sched/fair.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 0959a770ecc0..ef44474b8fbf 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -8254,14 +8254,12 @@ check_cpu_capacity(struct rq *rq, struct sched_domain *sd) /* * Check whether a rq has a misfit task and if it looks like we can actually - * help that task: we can migrate the task to a CPU of higher capacity, or - * the task's current CPU is heavily pressured. + * help that task: we can migrate the task to a CPU of higher capacity. */ -static inline int check_misfit_status(struct rq *rq, struct sched_domain *sd) +static inline int check_misfit_status(struct rq *rq) { return rq->misfit_task_load && - (capacity_greater(rq->rd->max_cpu_capacity, rq->cpu_capacity_orig) || - check_cpu_capacity(rq, sd)); + capacity_greater(rq->rd->max_cpu_capacity, rq->cpu_capacity); } /* @@ -10238,7 +10236,7 @@ static void nohz_balancer_kick(struct rq *rq) * When ASYM_CPUCAPACITY; see if there's a higher capacity CPU * to run the misfit task on. */ - if (check_misfit_status(rq, sd)) { + if (check_misfit_status(rq)) { flags = NOHZ_KICK_MASK; goto unlock; } -- 2.27.0