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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 98566C35669 for ; Sun, 23 Feb 2020 02:34:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 60DC520659 for ; Sun, 23 Feb 2020 02:34:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582425253; bh=CzPNV9CXaZc0F2Z9A7VI8Xj2e4/spUA3pvhhstB0ESY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=cWDeLnX0qzsR/mIqpkzGDqLHzQCF8vSvYdG5/LGN3cFAsAUb1vPSpYOJOHqvF+HMT 9Go43s/2aWiORGvLwy2n4HZMSwbWv//Fni12lFpxxfQmX76Q5feCHv4UW15JAYGq0B FKmCwMo2AvCdUXjSMxiEMU3VqcbtQ7c9edaRT/Oc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728689AbgBWCeL (ORCPT ); Sat, 22 Feb 2020 21:34:11 -0500 Received: from mail.kernel.org ([198.145.29.99]:51726 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728235AbgBWCWk (ORCPT ); Sat, 22 Feb 2020 21:22:40 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 6B42022464; Sun, 23 Feb 2020 02:22:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582424560; bh=CzPNV9CXaZc0F2Z9A7VI8Xj2e4/spUA3pvhhstB0ESY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=upMfglOdcjwD8WLgfYUzcNptrC3gpwUBrwDS8NzWLFVlWPaGAE3gEVsU4zHDMS2gt 1/PebLQEeG/p6eDpNyjzEn3oNszBQoyRcQDyydKq0tKbua8v1LIM3mZGVIVCJuIyhp bt7FHB8Q1l/jhscSuAmKCBNAiR4ulfKTXAcwHYo0= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Scott Wood , Peter Zijlstra , Ingo Molnar , Sasha Levin Subject: [PATCH AUTOSEL 5.4 03/50] sched/core: Don't skip remote tick for idle CPUs Date: Sat, 22 Feb 2020 21:21:48 -0500 Message-Id: <20200223022235.1404-3-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200223022235.1404-1-sashal@kernel.org> References: <20200223022235.1404-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Scott Wood [ Upstream commit 488603b815a7514c7009e6fc339d74ed4a30f343 ] 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 Signed-off-by: Sasha Levin --- 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 dfaefb175ba05..5cbf64db4e0a3 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -3667,22 +3667,24 @@ 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: -- 2.20.1