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=-16.8 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 C0A4CC433B4 for ; Thu, 13 May 2021 15:50:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7C3EC61354 for ; Thu, 13 May 2021 15:50:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232455AbhEMPvN (ORCPT ); Thu, 13 May 2021 11:51:13 -0400 Received: from mga12.intel.com ([192.55.52.136]:24114 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230367AbhEMPvK (ORCPT ); Thu, 13 May 2021 11:51:10 -0400 IronPort-SDR: cCAFuc9YqUcwFMbods3z32qRCBj8aJNuE/IVItP/TP8dhAoTB0cUXPUFe2BnI6zdOZiD0wgEdr RiwgFASUnQFw== X-IronPort-AV: E=McAfee;i="6200,9189,9982"; a="179568907" X-IronPort-AV: E=Sophos;i="5.82,296,1613462400"; d="scan'208";a="179568907" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 May 2021 08:50:00 -0700 IronPort-SDR: mgTIT6acf6icv6Y+UBT/PnSrwhPzcPptTdPvN3IriIvzorH9Qt+stwsvC1pkt1lOjM8trA21dh aL84eIv3YSyQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.82,296,1613462400"; d="scan'208";a="610418829" Received: from ranerica-svr.sc.intel.com ([172.25.110.23]) by orsmga005.jf.intel.com with ESMTP; 13 May 2021 08:49:59 -0700 From: Ricardo Neri To: "Peter Zijlstra (Intel)" , Ingo Molnar , Juri Lelli , Vincent Guittot Cc: Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Len Brown , Srinivas Pandruvada , Tim Chen , Aubrey Li , "Ravi V. Shankar" , Ricardo Neri , Quentin Perret , "Joel Fernandes (Google)" , linux-kernel@vger.kernel.org, Ricardo Neri , Aubrey Li , Daniel Bristot de Oliveira Subject: [PATCH v3 2/6] sched/fair: Optimize checking for group_asym_packing Date: Thu, 13 May 2021 08:49:05 -0700 Message-Id: <20210513154909.6385-3-ricardo.neri-calderon@linux.intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210513154909.6385-1-ricardo.neri-calderon@linux.intel.com> References: <20210513154909.6385-1-ricardo.neri-calderon@linux.intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org sched_asmy_prefer(a, b) returns true if the priority of cpu a is bigger than the priority of b. dst_cpu belongs to the local group. It follows that its priority is equal or less than the priority of the preferred CPU of the local group. Thus, sched_asmy_prefer() always returns false when called on the local group. By checking local_group, we can avoid additional checks and invoking sched_asmy_prefer() when it is not needed. Cc: Aubrey Li Cc: Ben Segall Cc: Daniel Bristot de Oliveira Cc: Dietmar Eggemann Cc: Joel Fernandes (Google) Cc: Mel Gorman Cc: Quentin Perret Cc: Srinivas Pandruvada Cc: Steven Rostedt Cc: Tim Chen Reviewed-by: Len Brown Signed-off-by: Ricardo Neri --- Changes since v2: * Reworded commit message for clarity. (Peter Z) Changes since v1: * None --- 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 161b92aa1c79..96b023432a1c 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -8507,7 +8507,7 @@ static inline void update_sg_lb_stats(struct lb_env *env, } /* Check if dst CPU is idle and preferred to this group */ - if (env->sd->flags & SD_ASYM_PACKING && + if (!local_group && env->sd->flags & SD_ASYM_PACKING && env->idle != CPU_NOT_IDLE && sgs->sum_h_nr_running && sched_asym_prefer(env->dst_cpu, group->asym_prefer_cpu)) { -- 2.17.1