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=-11.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 08EB4C33CB1 for ; Fri, 17 Jan 2020 10:09:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D0BCF2087E for ; Fri, 17 Jan 2020 10:09:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729355AbgAQKJh (ORCPT ); Fri, 17 Jan 2020 05:09:37 -0500 Received: from Galois.linutronix.de ([193.142.43.55]:55435 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729195AbgAQKJO (ORCPT ); Fri, 17 Jan 2020 05:09:14 -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 1isOYY-0005TH-CM; Fri, 17 Jan 2020 11:08:46 +0100 Received: from [127.0.1.1] (localhost [IPv6:::1]) by tip-bot2.lab.linutronix.de (Postfix) with ESMTP id 5EBE41C19D2; Fri, 17 Jan 2020 11:08:42 +0100 (CET) Date: Fri, 17 Jan 2020 10:08:42 -0000 From: "tip-bot2 for Wei Li" Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: sched/core] sched/debug: Reset watchdog on all CPUs while processing sysrq-t Cc: Wei Li , "Peter Zijlstra (Intel)" , "Steven Rostedt (VMware)" , x86 , LKML In-Reply-To: <20191226085224.48942-1-liwei391@huawei.com> References: <20191226085224.48942-1-liwei391@huawei.com> MIME-Version: 1.0 Message-ID: <157925572220.396.10027500952114963200.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: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 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: 02d4ac5885a18d326b500b94808f0956dcce2832 Gitweb: https://git.kernel.org/tip/02d4ac5885a18d326b500b94808f0956dcce2832 Author: Wei Li AuthorDate: Thu, 26 Dec 2019 16:52:24 +08:00 Committer: Peter Zijlstra CommitterDate: Fri, 17 Jan 2020 10:19:20 +01:00 sched/debug: Reset watchdog on all CPUs while processing sysrq-t Lengthy output of sysrq-t may take a lot of time on slow serial console with lots of processes and CPUs. So we need to reset NMI-watchdog to avoid spurious lockup messages, and we also reset softlockup watchdogs on all other CPUs since another CPU might be blocked waiting for us to process an IPI or stop_machine. Add to sysrq_sched_debug_show() as what we did in show_state_filter(). Signed-off-by: Wei Li Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Steven Rostedt (VMware) Link: https://lkml.kernel.org/r/20191226085224.48942-1-liwei391@huawei.com --- kernel/sched/debug.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c index f7e4579..879d3cc 100644 --- a/kernel/sched/debug.c +++ b/kernel/sched/debug.c @@ -751,9 +751,16 @@ void sysrq_sched_debug_show(void) int cpu; sched_debug_header(NULL); - for_each_online_cpu(cpu) + for_each_online_cpu(cpu) { + /* + * Need to reset softlockup watchdogs on all CPUs, because + * another CPU might be blocked waiting for us to process + * an IPI or stop_machine. + */ + touch_nmi_watchdog(); + touch_all_softlockup_watchdogs(); print_cpu(NULL, cpu); - + } } /*