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=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=unavailable 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 2856BC49EBF for ; Mon, 21 Jun 2021 16:48:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 112BC6134F for ; Mon, 21 Jun 2021 16:48:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231627AbhFUQuR (ORCPT ); Mon, 21 Jun 2021 12:50:17 -0400 Received: from mail.kernel.org ([198.145.29.99]:37672 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234027AbhFUQqA (ORCPT ); Mon, 21 Jun 2021 12:46:00 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 2E8E2613B2; Mon, 21 Jun 2021 16:33:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1624293189; bh=6FbYkhJMn2N0WyVHtkjTZp2t6XKY0Cc1Iu8MvkMCgdY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=xx5I5ghLDnzSTHcI6wAi8TJymUF4mdfZP4/2vlqrB3jm/CIBMu+ytKCz5UXLSMGLB OJvla+GwaQXH/wGuhvth5E5PfHi5YFU28VUQzz+SqPix378qEt+ikGtRmi/eT4tBaW p3XdHYpz7Semkxh25YQU3kz4FS9R/5dHoA+uNoXk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vincent Guittot , "Peter Zijlstra (Intel)" , Sasha Levin Subject: [PATCH 5.12 098/178] sched/pelt: Ensure that *_sum is always synced with *_avg Date: Mon, 21 Jun 2021 18:15:12 +0200 Message-Id: <20210621154926.100007082@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210621154921.212599475@linuxfoundation.org> References: <20210621154921.212599475@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Vincent Guittot [ Upstream commit fcf6631f3736985ec89bdd76392d3c7bfb60119f ] Rounding in PELT calculation happening when entities are attached/detached of a cfs_rq can result into situations where util/runnable_avg is not null but util/runnable_sum is. This is normally not possible so we need to ensure that util/runnable_sum stays synced with util/runnable_avg. detach_entity_load_avg() is the last place where we don't sync util/runnable_sum with util/runnbale_avg when moving some sched_entities Signed-off-by: Vincent Guittot Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20210601085832.12626-1-vincent.guittot@linaro.org Signed-off-by: Sasha Levin --- kernel/sched/fair.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 487312a5ceab..47fcc3fe9dc5 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -3760,11 +3760,17 @@ static void attach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *s */ static void detach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se) { + /* + * cfs_rq->avg.period_contrib can be used for both cfs_rq and se. + * See ___update_load_avg() for details. + */ + u32 divider = get_pelt_divider(&cfs_rq->avg); + dequeue_load_avg(cfs_rq, se); sub_positive(&cfs_rq->avg.util_avg, se->avg.util_avg); - sub_positive(&cfs_rq->avg.util_sum, se->avg.util_sum); + cfs_rq->avg.util_sum = cfs_rq->avg.util_avg * divider; sub_positive(&cfs_rq->avg.runnable_avg, se->avg.runnable_avg); - sub_positive(&cfs_rq->avg.runnable_sum, se->avg.runnable_sum); + cfs_rq->avg.runnable_sum = cfs_rq->avg.runnable_avg * divider; add_tg_cfs_propagate(cfs_rq, -se->avg.load_sum); -- 2.30.2