From nobody Sun Feb 8 22:05:38 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8021AC7EE23 for ; Wed, 7 Jun 2023 18:10:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232455AbjFGSKQ (ORCPT ); Wed, 7 Jun 2023 14:10:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55566 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229488AbjFGSKO (ORCPT ); Wed, 7 Jun 2023 14:10:14 -0400 Received: from mail-pg1-x52b.google.com (mail-pg1-x52b.google.com [IPv6:2607:f8b0:4864:20::52b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6A5E395 for ; Wed, 7 Jun 2023 11:10:13 -0700 (PDT) Received: by mail-pg1-x52b.google.com with SMTP id 41be03b00d2f7-542c54455e7so2541824a12.1 for ; Wed, 07 Jun 2023 11:10:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1686161413; x=1688753413; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=qV89SGlXzzybQ68Kw8PJEO9/Nh725SOfx0EhcbhN+uM=; b=MlIQ2lv7KlNWK5bTcU/eBzyeeSymLF/3Fmuubmagj4IwYvTEJ6U7Hcc2GGiWZs7vHP ziB2X20BURh/p018DaAbGDrvSsbQq7DZaVoHJ8caM1XZwY09/3YE90u2l/kEzxrtrDRJ DsxjZn9Ya4mUGMkv4nFzEfJfEXSp6IbUrCIy9BLoaaVnT2WtZKrak9X8tMi60LRmWOyu aPRGrNCKIJrKDl9kjnZztONoM53cJ7yNLJfrBC21KPl3o0bbNn9zm9RzZeQZVnU/ZSpR E2FPA/bxTLuhIKmSRf3Y7+lkVGdlwTErOA2lp3cxL7m3W3ja05GC7W8f5XlvCdaiAlbr Gdhg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1686161413; x=1688753413; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=qV89SGlXzzybQ68Kw8PJEO9/Nh725SOfx0EhcbhN+uM=; b=aISCt7wk4L/lCWIzX0GzhaF0o9g+Bw4uf1UoRSt1t+5DEcvR69HCB5iljJ9z+mSf+i Z+kSoaNbSp8yw1n1sbUGlSJbvG69fLSruwWYeNc3rVwO/kVngdiy0hPMxbOab5wwAvPF 18l3UmYws3q2h1s2lq/lsM0bAuNFHai0Ucwk4IgmRbOyHUcXsxKkYUz1XGWN+wU64NtP /IqeDD9wfZ5B9hEDKa11gMbSRiBFlUjlY5hYARkeM2waAR19NwZUC1IpgM31Qwe2RSP0 f7BAMd/bBuTVGLfQX01e/dDuA+k0PNtwYcS3Epw4JjwcEvPlO7447CK4JzA3d7qk9vGf 7Cdg== X-Gm-Message-State: AC+VfDw1SqNaYv4osc5BX3nadEDk3mR/iYWvkYZ2HO4CNe6TAjlqfiC+ WnlY0tBdvwhO4Jh9KiT5d7s= X-Google-Smtp-Source: ACHHUZ4dNWuBZx8yG1Fojwq+zZrRDyVXt2jaoWh3tFYU54a1r4437PQWroeeP6lUyVAVfpwOkyzNqA== X-Received: by 2002:a17:90b:190f:b0:246:85ec:d816 with SMTP id mp15-20020a17090b190f00b0024685ecd816mr2333613pjb.3.1686161412765; Wed, 07 Jun 2023 11:10:12 -0700 (PDT) Received: from VAN-928222-PC0.fortinet-us.com ([173.214.130.2]) by smtp.gmail.com with ESMTPSA id cm14-20020a17090afa0e00b00256799877ffsm1623918pjb.47.2023.06.07.11.10.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 07 Jun 2023 11:10:11 -0700 (PDT) From: Qingjie Xing To: mingo@redhat.com Cc: peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, vschneid@redhat.com, brauner@kernel.org, linux-kernel@vger.kernel.org, xqjcool@gmail.com Subject: [PATCH] sched/debug,sched/core: Reset hung task detector while processing sysrq-t Date: Wed, 7 Jun 2023 11:09:58 -0700 Message-Id: <20230607180958.4112039-1-xqjcool@gmail.com> X-Mailer: git-send-email 2.40.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" On devices with multiple CPUs and multiple processes, outputting lengthy sysrq-t content on a slow serial port can consume a significant amount of time. We need to reset the hung task detector to avoid false hung task alerts. Signed-off-by: Qingjie Xing --- kernel/sched/core.c | 1 + kernel/sched/debug.c | 1 + 2 files changed, 2 insertions(+) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index a68d1276bab0..5773283b752c 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -9176,6 +9176,7 @@ void show_state_filter(unsigned int state_filter) */ touch_nmi_watchdog(); touch_all_softlockup_watchdogs(); + reset_hung_task_detector(); if (state_filter_match(state_filter, p)) sched_show_task(p); } diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c index 0b2340a79b65..43065808b425 100644 --- a/kernel/sched/debug.c +++ b/kernel/sched/debug.c @@ -904,6 +904,7 @@ void sysrq_sched_debug_show(void) */ touch_nmi_watchdog(); touch_all_softlockup_watchdogs(); + reset_hung_task_detector(); print_cpu(NULL, cpu); } } --=20 2.40.1