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=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 82DEEC35247 for ; Thu, 6 Feb 2020 19:20:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5B99420659 for ; Thu, 6 Feb 2020 19:20:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728098AbgBFTUX (ORCPT ); Thu, 6 Feb 2020 14:20:23 -0500 Received: from foss.arm.com ([217.140.110.172]:33700 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727946AbgBFTUS (ORCPT ); Thu, 6 Feb 2020 14:20:18 -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 2AF801063; Thu, 6 Feb 2020 11:20:18 -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 CFE1D3F52E; Thu, 6 Feb 2020 11:20:16 -0800 (PST) From: Valentin Schneider To: linux-kernel@vger.kernel.org Cc: mingo@redhat.com, peterz@infradead.org, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, morten.rasmussen@arm.com, qperret@google.com, adharmap@codeaurora.org, pkondeti@codeaurora.org Subject: [PATCH v4 4/4] sched/fair: Kill wake_cap() Date: Thu, 6 Feb 2020 19:19:57 +0000 Message-Id: <20200206191957.12325-5-valentin.schneider@arm.com> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20200206191957.12325-1-valentin.schneider@arm.com> References: <20200206191957.12325-1-valentin.schneider@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Morten Rasmussen Capacity-awareness in the wake-up path previously involved disabling wake_affine in certain scenarios. We have just made select_idle_sibling() capacity-aware, so this isn't needed anymore. Remove wake_cap() entirely. Signed-off-by: Morten Rasmussen [Changelog tweaks] Signed-off-by: Valentin Schneider --- kernel/sched/fair.c | 30 +----------------------------- 1 file changed, 1 insertion(+), 29 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 9a5a6e9d2375e..9eedf1d6de3a1 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -6143,33 +6143,6 @@ static unsigned long cpu_util_without(int cpu, struct task_struct *p) return min_t(unsigned long, util, capacity_orig_of(cpu)); } -/* - * Disable WAKE_AFFINE in the case where task @p doesn't fit in the - * capacity of either the waking CPU @cpu or the previous CPU @prev_cpu. - * - * In that case WAKE_AFFINE doesn't make sense and we'll let - * BALANCE_WAKE sort things out. - */ -static int wake_cap(struct task_struct *p, int cpu, int prev_cpu) -{ - long min_cap, max_cap; - - if (!static_branch_unlikely(&sched_asym_cpucapacity)) - return 0; - - min_cap = min(capacity_orig_of(prev_cpu), capacity_orig_of(cpu)); - max_cap = cpu_rq(cpu)->rd->max_cpu_capacity; - - /* Minimum capacity is close to max, no need to abort wake_affine */ - if (max_cap - min_cap < max_cap >> 3) - return 0; - - /* Bring task utilization in sync with prev_cpu */ - sync_entity_load_avg(&p->se); - - return !task_fits_capacity(p, min_cap); -} - /* * Predicts what cpu_util(@cpu) would return if @p was migrated (and enqueued) * to @dst_cpu. @@ -6434,8 +6407,7 @@ select_task_rq_fair(struct task_struct *p, int prev_cpu, int sd_flag, int wake_f new_cpu = prev_cpu; } - want_affine = !wake_wide(p) && !wake_cap(p, cpu, prev_cpu) && - cpumask_test_cpu(cpu, p->cpus_ptr); + want_affine = !wake_wide(p) && cpumask_test_cpu(cpu, p->cpus_ptr); } rcu_read_lock(); -- 2.24.0