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 62273C48BC2 for ; Mon, 21 Jun 2021 16:33:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 521A361414 for ; Mon, 21 Jun 2021 16:33:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232000AbhFUQgE (ORCPT ); Mon, 21 Jun 2021 12:36:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:54924 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232157AbhFUQcE (ORCPT ); Mon, 21 Jun 2021 12:32:04 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id EAB2C61408; Mon, 21 Jun 2021 16:25:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1624292751; bh=xBVlUaKeBfgoVvMvOGT6OdGSFsRM915ESXJTPKiib0k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TIY03PMZfoNW3pUwE3lDvZJlKGdYDeHrWR3c7s1Jav0UdmZKfq954+p4XUYBLXg2h 3HZ6djqOxwXNcnhispRibdmnyzaDuju0waeVmvs7QlKuVZTUyxNQ174+pcybeBFjje ZHvU/ln3/vd8dNNHZ8g8mD+GM4HqxVCrf5S+fof8= 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 5.10 083/146] sched/pelt: Ensure that *_sum is always synced with *_avg Date: Mon, 21 Jun 2021 18:15:13 +0200 Message-Id: <20210621154916.297306183@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210621154911.244649123@linuxfoundation.org> References: <20210621154911.244649123@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 ff8a172a69ca..d6e1c90de570 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -3767,11 +3767,17 @@ 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