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=-9.8 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 87FB6C433E0 for ; Wed, 20 May 2020 13:43:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 660AA207D3 for ; Wed, 20 May 2020 13:43:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726824AbgETNnM (ORCPT ); Wed, 20 May 2020 09:43:12 -0400 Received: from foss.arm.com ([217.140.110.172]:56500 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726439AbgETNnK (ORCPT ); Wed, 20 May 2020 09:43:10 -0400 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 68AC4D6E; Wed, 20 May 2020 06:43:10 -0700 (PDT) Received: from dell3630.arm.com (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 72E593F52E; Wed, 20 May 2020 06:43:07 -0700 (PDT) From: Dietmar Eggemann To: Ingo Molnar , Peter Zijlstra , Juri Lelli Cc: Vincent Guittot , Steven Rostedt , Luca Abeni , Daniel Bristot de Oliveira , Wei Wang , Quentin Perret , Alessio Balsini , Pavan Kondeti , Patrick Bellasi , Morten Rasmussen , Valentin Schneider , Qais Yousef , linux-kernel@vger.kernel.org Subject: [PATCH v3 1/5] sched/deadline: Optimize dl_bw_cpus() Date: Wed, 20 May 2020 15:42:39 +0200 Message-Id: <20200520134243.19352-2-dietmar.eggemann@arm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200520134243.19352-1-dietmar.eggemann@arm.com> References: <20200520134243.19352-1-dietmar.eggemann@arm.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return the weight of the root domain (rd) span in case it is a subset of the cpu_active_mask. Continue to compute the number of CPUs over rd span and cpu_active_mask when in hotplug. Signed-off-by: Dietmar Eggemann --- kernel/sched/deadline.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index 504d2f51b0d6..4ae22bfc37ae 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -54,10 +54,16 @@ static inline struct dl_bw *dl_bw_of(int i) static inline int dl_bw_cpus(int i) { struct root_domain *rd = cpu_rq(i)->rd; - int cpus = 0; + int cpus; RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(), "sched RCU must be held"); + + if (cpumask_subset(rd->span, cpu_active_mask)) + return cpumask_weight(rd->span); + + cpus = 0; + for_each_cpu_and(i, rd->span, cpu_active_mask) cpus++; -- 2.17.1