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=-9.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_DBL_ABUSE_MALW 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 88793C33CB7 for ; Wed, 29 Jan 2020 11:33:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 630CE20732 for ; Wed, 29 Jan 2020 11:33:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726858AbgA2LdU (ORCPT ); Wed, 29 Jan 2020 06:33:20 -0500 Received: from Galois.linutronix.de ([193.142.43.55]:51126 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726795AbgA2LdQ (ORCPT ); Wed, 29 Jan 2020 06:33:16 -0500 Received: from [5.158.153.53] (helo=tip-bot2.lab.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1iwlaj-0007op-1Y; Wed, 29 Jan 2020 12:33:05 +0100 Received: from [127.0.1.1] (localhost [IPv6:::1]) by tip-bot2.lab.linutronix.de (Postfix) with ESMTP id 9EFB71C1C1E; Wed, 29 Jan 2020 12:33:00 +0100 (CET) Date: Wed, 29 Jan 2020 11:33:00 -0000 From: "tip-bot2 for Scott Wood" Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: sched/core] sched/core: Don't skip remote tick for idle CPUs Cc: Scott Wood , "Peter Zijlstra (Intel)" , Ingo Molnar , x86 , LKML In-Reply-To: <1578736419-14628-2-git-send-email-swood@redhat.com> References: <1578736419-14628-2-git-send-email-swood@redhat.com> MIME-Version: 1.0 Message-ID: <158029758043.396.4187118276137508123.tip-bot2@tip-bot2> X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Linutronix-Spam-Score: 1.5 X-Linutronix-Spam-Level: + X-Linutronix-Spam-Status: No , 1.5 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001,URIBL_DBL_ABUSE_MALW=2.5 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the sched/core branch of tip: Commit-ID: 488603b815a7514c7009e6fc339d74ed4a30f343 Gitweb: https://git.kernel.org/tip/488603b815a7514c7009e6fc339d74ed4a30f343 Author: Scott Wood AuthorDate: Sat, 11 Jan 2020 04:53:38 -05:00 Committer: Ingo Molnar CommitterDate: Tue, 28 Jan 2020 21:36:16 +01:00 sched/core: Don't skip remote tick for idle CPUs This will be used in the next patch to get a loadavg update from nohz cpus. The delta check is skipped because idle_sched_class doesn't update se.exec_start. Signed-off-by: Scott Wood Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Link: https://lkml.kernel.org/r/1578736419-14628-2-git-send-email-swood@redhat.com --- kernel/sched/core.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index fc1dfc0..cf8b33d 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -3669,22 +3669,24 @@ static void sched_tick_remote(struct work_struct *work) * statistics and checks timeslices in a time-independent way, regardless * of when exactly it is running. */ - if (idle_cpu(cpu) || !tick_nohz_tick_stopped_cpu(cpu)) + if (!tick_nohz_tick_stopped_cpu(cpu)) goto out_requeue; rq_lock_irq(rq, &rf); curr = rq->curr; - if (is_idle_task(curr) || cpu_is_offline(cpu)) + if (cpu_is_offline(cpu)) goto out_unlock; update_rq_clock(rq); - delta = rq_clock_task(rq) - curr->se.exec_start; - /* - * Make sure the next tick runs within a reasonable - * amount of time. - */ - WARN_ON_ONCE(delta > (u64)NSEC_PER_SEC * 3); + if (!is_idle_task(curr)) { + /* + * Make sure the next tick runs within a reasonable + * amount of time. + */ + delta = rq_clock_task(rq) - curr->se.exec_start; + WARN_ON_ONCE(delta > (u64)NSEC_PER_SEC * 3); + } curr->sched_class->task_tick(rq, curr, 0); out_unlock: