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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 C28A8C4360C for ; Thu, 1 Apr 2021 03:33:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 92DD861155 for ; Thu, 1 Apr 2021 03:33:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233570AbhDADcW (ORCPT ); Wed, 31 Mar 2021 23:32:22 -0400 Received: from mail-m118208.qiye.163.com ([115.236.118.208]:39198 "EHLO mail-m118208.qiye.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233530AbhDADcE (ORCPT ); Wed, 31 Mar 2021 23:32:04 -0400 Received: from vivo-HP-ProDesk-680-G4-PCI-MT.vivo.xyz (unknown [58.251.74.232]) by mail-m118208.qiye.163.com (Hmail) with ESMTPA id 9CFB2E014C; Thu, 1 Apr 2021 11:32:01 +0800 (CST) From: Wang Qing To: Jonathan Corbet , Joe Perches , Wang Qing , Mauro Carvalho Chehab , Stephen Kitt , Andrew Morton , Kees Cook , Randy Dunlap , "Guilherme G. Piccoli" , Eric Biggers , Qais Yousef , Petr Mladek , Vlastimil Babka , Santosh Sivaraj , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Alexey Budankov Cc: gregkh@linuxfoundation.org Subject: [PATCH V2 2/4] doc: watchdog: Delete the explanation about "watchdog/%u". Date: Thu, 1 Apr 2021 11:31:32 +0800 Message-Id: <1617247900-23813-3-git-send-email-wangqing@vivo.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1617247900-23813-1-git-send-email-wangqing@vivo.com> References: <1617247900-23813-1-git-send-email-wangqing@vivo.com> X-HM-Spam-Status: e1kfGhgUHx5ZQUtXWQgYFAkeWUFZS1VLWVdZKFlBSE83V1ktWUFJV1kPCR oVCBIfWUFZShlMTkxCGB5JHU5NVkpNSkxJT0xCSUlISkNVEwETFhoSFyQUDg9ZV1kWGg8SFR0UWU FZT0tIVUpKS0hKTFVLWQY+ X-HM-Sender-Digest: e1kMHhlZQR0aFwgeV1kSHx4VD1lBWUc6NjI6Fjo6LT8ISzQcSRwpPSoq TEswCQJVSlVKTUpMSU9MQklJTUlCVTMWGhIXVQwaFRwKEhUcOw0SDRRVGBQWRVlXWRILWUFZTkNV SU5KVUxPVUlISVlXWQgBWUFITEpJNwY+ X-HM-Tid: 0a788b7ce8412c17kusn9cfb2e014c Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org "watchdog/%u" threads has be replaced by cpu_stop_work. The current description is extremely misleading, so delete the explanation about "watchdog/%u". Signed-off-by: Wang Qing --- .../admin-guide/kernel-per-CPU-kthreads.rst | 20 -------------------- 1 file changed, 20 deletions(-) diff --git a/Documentation/admin-guide/kernel-per-CPU-kthreads.rst b/Documentation/admin-guide/kernel-per-CPU-kthreads.rst index 531f689..5e51ee5 --- a/Documentation/admin-guide/kernel-per-CPU-kthreads.rst +++ b/Documentation/admin-guide/kernel-per-CPU-kthreads.rst @@ -332,23 +332,3 @@ To reduce its OS jitter, do at least one of the following: kthreads from being created in the first place. However, please note that this will not eliminate OS jitter, but will instead shift it to RCU_SOFTIRQ. - -Name: - watchdog/%u - -Purpose: - Detect software lockups on each CPU. - -To reduce its OS jitter, do at least one of the following: - -1. Build with CONFIG_LOCKUP_DETECTOR=n, which will prevent these - kthreads from being created in the first place. -2. Boot with "nosoftlockup=0", which will also prevent these kthreads - from being created. Other related watchdog and softlockup boot - parameters may be found in Documentation/admin-guide/kernel-parameters.rst - and Documentation/watchdog/watchdog-parameters.rst. -3. Echo a zero to /proc/sys/kernel/watchdog to disable the - watchdog timer. -4. Echo a large number of /proc/sys/kernel/watchdog_thresh in - order to reduce the frequency of OS jitter due to the watchdog - timer down to a level that is acceptable for your workload. -- 2.7.4