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=-11.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,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 1BAE0C433FE for ; Tue, 8 Dec 2020 15:36:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CFB0223A7A for ; Tue, 8 Dec 2020 15:36:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730081AbgLHPgF (ORCPT ); Tue, 8 Dec 2020 10:36:05 -0500 Received: from outbound-smtp19.blacknight.com ([46.22.139.246]:45239 "EHLO outbound-smtp19.blacknight.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730001AbgLHPgE (ORCPT ); Tue, 8 Dec 2020 10:36:04 -0500 Received: from mail.blacknight.com (pemlinmail04.blacknight.ie [81.17.254.17]) by outbound-smtp19.blacknight.com (Postfix) with ESMTPS id 196721C3B7A for ; Tue, 8 Dec 2020 15:35:13 +0000 (GMT) Received: (qmail 9668 invoked from network); 8 Dec 2020 15:35:12 -0000 Received: from unknown (HELO stampy.112glenside.lan) (mgorman@techsingularity.net@[84.203.22.4]) by 81.17.254.9 with ESMTPA; 8 Dec 2020 15:35:12 -0000 From: Mel Gorman To: Peter Ziljstra , Ingo Molnar , LKML Cc: Aubrey Li , Barry Song , Juri Lelli , Vincent Guittot , Valentin Schneider , Linux-ARM , Mel Gorman Subject: [PATCH 0/4] Reduce scanning of runqueues in select_idle_sibling Date: Tue, 8 Dec 2020 15:34:57 +0000 Message-Id: <20201208153501.1467-1-mgorman@techsingularity.net> X-Mailer: git-send-email 2.26.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Changelog since v1 o Drop single-pass patch (vincent) o Scope variables used for SIS_AVG_CPU (dietmar) o Remove redundant assignment (dietmar This reduces the amount of runqueue scanning in select_idle_sibling in the worst case. Patch 1 removes SIS_AVG_CPU because it's unused. Patch 2 moves all SIS_PROP-related calculations under SIS_PROP Patch 3 improves the hit rate of p->recent_used_cpu to reduce the amount of scanning. It should be relatively uncontroversial Patch 4 returns an idle candidate if one is found while scanning for a free core. -- 2.26.2 Mel Gorman (4): sched/fair: Remove SIS_AVG_CPU sched/fair: Move avg_scan_cost calculations under SIS_PROP sched/fair: Do not replace recent_used_cpu with the new target sched/fair: Return an idle cpu if one is found after a failed search for an idle core kernel/sched/fair.c | 51 ++++++++++++++++++++--------------------- kernel/sched/features.h | 1 - 2 files changed, 25 insertions(+), 27 deletions(-) -- 2.26.2