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=-0.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 C914EC433DF for ; Thu, 2 Jul 2020 17:43:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A3F3B2084C for ; Thu, 2 Jul 2020 17:43:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="s2m3Az4y" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727835AbgGBRnu (ORCPT ); Thu, 2 Jul 2020 13:43:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49454 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726980AbgGBRnu (ORCPT ); Thu, 2 Jul 2020 13:43:50 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 15F0DC08C5C1; Thu, 2 Jul 2020 10:43:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=c/ti3Um2rPtpXRIbW8ekfcfzcaaYCWd/840Frp0eP3o=; b=s2m3Az4ylcJFcwqyRY0E7W7bHu 0LB8UEJflQmqt3eVWI+VA7JnS1krSA4llJDvzFFTEk0BEZgcTEcr9bibqZ+pbejTQwKc2ieHeoWt7 xeMRWwCGaeSMnE5sAjqgoK9zk3BdbHrEy9/7Diuu5/iOs7OnGIfos1WYU2QKB2lbFbyUFPpuuuVWW TGraCLbetLk06bwIQElLtZCouwg2Giaa9r5nlJ4IzQEkW86053fZabVt2ZIpa3FbY6KsZ6ZAS1Ytw MKbmaxBPDVBW01KR4p9CxtuWqP4nt/10bwIelpfgJ63o9ZPlZ9G+sOtQvXd2U+XT4fGXTvYGuk0BA tfPmYLrw==; Received: from willy by casper.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1jr3FS-0004Pj-Hp; Thu, 02 Jul 2020 17:43:46 +0000 Date: Thu, 2 Jul 2020 18:43:46 +0100 From: Matthew Wilcox To: yang che Cc: mcgrof@kernel.org, keescook@chromium.org, yzaikin@google.com, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [RFC] hung_task:add detecting task in D state milliseconds timeout Message-ID: <20200702174346.GB25523@casper.infradead.org> References: <1593698893-6371-1-git-send-email-chey84736@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1593698893-6371-1-git-send-email-chey84736@gmail.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 02, 2020 at 10:08:13PM +0800, yang che wrote: > current hung_task_check_interval_secs and hung_task_timeout_secs > only supports seconds.in some cases,the TASK_UNINTERRUPTIBLE state > takes less than 1 second.The task of the graphical interface, > the unterruptible state lasts for hundreds of milliseconds > will cause the interface to freeze The primary problem I see with this patch is that writing to the millisecond file silently overrides the setting in the seconds file. If you end up redoing this patch, there needs to be one variable which is scaled when reading/writing the seconds file. Taking a step back though, I think this is the wrong tool for the job. I'm pretty sure KernelShark will do what you want without any kernel modifications.