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=-3.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 531EEC0044C for ; Mon, 5 Nov 2018 14:54:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 257312085B for ; Mon, 5 Nov 2018 14:54:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 257312085B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387396AbeKFAOV (ORCPT ); Mon, 5 Nov 2018 19:14:21 -0500 Received: from foss.arm.com ([217.140.101.70]:45286 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726255AbeKFAOV (ORCPT ); Mon, 5 Nov 2018 19:14:21 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5E922A78; Mon, 5 Nov 2018 06:54:16 -0800 (PST) Received: from e110439-lin.cambridge.arm.com (e110439-lin.cambridge.arm.com [10.1.194.43]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 4C6AC3F5CF; Mon, 5 Nov 2018 06:54:14 -0800 (PST) From: Patrick Bellasi To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Peter Zijlstra , Vincent Guittot , Quentin Perret , Dietmar Eggemann , Morten Rasmussen , Juri Lelli , Todd Kjos , Steve Muckle , Suren Baghdasaryan Subject: [PATCH v2 0/3] util_est regression fixup and cleanups Date: Mon, 5 Nov 2018 14:53:57 +0000 Message-Id: <20181105145400.935-1-patrick.bellasi@arm.com> X-Mailer: git-send-email 2.18.0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is a respin of: https://lore.kernel.org/lkml/20181030160947.19581-1-patrick.bellasi@arm.com/ rebased on v4.20-rc1, which addresses Peter's comments by also adding a couple of additional cleanup patches on top. Tests on a 40 CPUs Intel(R) Xeon(R) CPU E5-2690 v2 @ 3.00GHz system still reports the ~10-15% Execl Throughput improvements after applying the first patch. Those benefits are not there if we remove the additional test on "current == p" which Peter was asking about. I guess the race condition described in the new inline comment I've now added could be the reason for the additional test being required, but I did not really verified that guess. I've just kept both conditions but swapped them since we will probably be more likely to call cpu_util_without() with a task which is eventually marked as task_on_rq_queued(). The second patch is pretty simple, while the last one implements what Peter suggested in the previous review. I did not used something similar to sub_positive, as suggested by Peter, just because in my tests that implementation seems to affect negatively the Execl Throughput tests results by reducing the speedup we get with the proposed version. Best Patrick Patrick Bellasi (3): sched/fair: util_est: fix cpu_util_wake for execl sched/fair: util_est: mask UTIL_AVG_UNCHANGED usages sched/fair: add lsub_positive and use it consistently kernel/sched/fair.c | 85 ++++++++++++++++++++++++++++++++++----------- 1 file changed, 64 insertions(+), 21 deletions(-) -- 2.18.0