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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7FD17C021AA for ; Thu, 20 Feb 2025 02:26:07 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id EFFF1280289; Wed, 19 Feb 2025 21:26:06 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id EB012280286; Wed, 19 Feb 2025 21:26:06 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D02E7280289; Wed, 19 Feb 2025 21:26:06 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id B0A9A280286 for ; Wed, 19 Feb 2025 21:26:06 -0500 (EST) Received: from smtpin26.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 5173C4B455 for ; Thu, 20 Feb 2025 02:26:06 +0000 (UTC) X-FDA: 83138733132.26.800CC99 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by imf07.hostedemail.com (Postfix) with ESMTP id E971E40002 for ; Thu, 20 Feb 2025 02:26:03 +0000 (UTC) Authentication-Results: imf07.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b="PK6QRJH/"; spf=pass (imf07.hostedemail.com: domain of llong@redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=llong@redhat.com; dmarc=pass (policy=none) header.from=redhat.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1740018364; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=Tz6TwNHIIl1eKIpDBxUFJaXjCys92nDICCxDwSUHx3E=; b=MYT+3w9nvLU54PcJ2f7LcBggxYc/QY6Kn3TJw7n7LijlAFKYCf28C5ZnHXJ+cLE6pRD/q1 cs/6yl3V1QOsO8eNk+nwVLcIGe1qzvNAV0ZLJoA/iCETvpC5JGjGrcoaz2YLGKLs3Epx5T 1pm8I3lw/oMh5gk9S4eRtdhrgNM2p7k= ARC-Authentication-Results: i=1; imf07.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b="PK6QRJH/"; spf=pass (imf07.hostedemail.com: domain of llong@redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=llong@redhat.com; dmarc=pass (policy=none) header.from=redhat.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1740018364; a=rsa-sha256; cv=none; b=PfSHUVwCpCp6pOIjwdv8KR9QmGecv+DIDe0PfvjAMw4Lh1Z466bFsLYcm9wzHhhHbumrsz 5BoxemkmL0psbMncn584AfhB3AB8rR6SE5BiGnSWZWHK30W9Q2+odYjhy/5wvch7ARxH08 AK5U8/ZAagg+8A0YCLg/BAJoQtaPO8o= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1740018363; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Tz6TwNHIIl1eKIpDBxUFJaXjCys92nDICCxDwSUHx3E=; b=PK6QRJH/OyOoQGQuDbXWlDkK8KxutxkgPcpUfA0lpkvsOCwoZe7adqZ26braMo5lTawLTN brVrgT5JRbhpo/bswdhmDNXLtBhg3gRrZbM5HPuQmlbXNxiAjB9ukb5/AtD5I/K9SYKOW8 1XT59XC7IatiQqfyi+1LY0bhxX3Btb0= Received: from mail-ot1-f70.google.com (mail-ot1-f70.google.com [209.85.210.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-636-AShfypegNyGx5TuiALrGlQ-1; Wed, 19 Feb 2025 21:26:02 -0500 X-MC-Unique: AShfypegNyGx5TuiALrGlQ-1 X-Mimecast-MFC-AGG-ID: AShfypegNyGx5TuiALrGlQ_1740018361 Received: by mail-ot1-f70.google.com with SMTP id 46e09a7af769-7272b9f0f38so149948a34.0 for ; Wed, 19 Feb 2025 18:26:02 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1740018361; x=1740623161; h=content-transfer-encoding:in-reply-to:content-language:references :cc:to:subject:user-agent:mime-version:date:message-id:from :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=Tz6TwNHIIl1eKIpDBxUFJaXjCys92nDICCxDwSUHx3E=; b=wn17ahxiIezXs3oEvqaHYCPmNGtWzaSvHfN5H5qXuR1byBrZxttDnCjfv+X27+AW+B 7erCaPpm7vffUSs1z+/W3GHALeOBchlfKhopOTC40ZB4Y7Q1fRJ/GCsgOihtNDaoTBZw VoLDvmC/vSG+F3f1JsTR2Je0iTxZGbOHo2DAR4rA0kmdMV8w0KaZjM/deXrZn5aioGkz /ug0VkqCeRakrg/cqDFxQJl0373AuN/ubAO3N0IBIMv0cgpTRwqwEVihZLlKOa73DyXw ehF4uWfNJetNDr0Z1kOPuw8WoAyGZUC+ccxWDDcuaNMKPSmIJfYualv/JDM991/ia8ia hXbA== X-Forwarded-Encrypted: i=1; AJvYcCX1Ohw2RWyxxmM6hlgpDZqB/iXL0Ov/qrhNm5QsH7QXUNCqfuu+C+Jgkah4Z8tNSl/o31yTn7LF+w==@kvack.org X-Gm-Message-State: AOJu0YwNMLOqV/pyELqcCqKPUWHMTmN2nQEN4hhQt8jsWNL/qTv9eTI8 ag+wCGFFkbLQuKG3oU0sjJ/r/cG/TjTcWcFQec8E5W1o7bjAU6aDmn3l8WDtK24d7LopAUNhybU wVKPNSc6yWx0OQ9JN9FKXT81fDEnvR4l6jzk544YkTT+/Vk5A X-Gm-Gg: ASbGncuQaRqVSoE4ROwOki9IGcXc2X3xn/fs3/FvtJN2Zkm7MtqHOID0gheXXAiTUa+ KX+2gOSuKN31mg6hp+ktz9rNvWsLIg2fby8LYqJvIAPtFSQa70RiYZbMDWRXLYICP7lxPH5NqdQ GcCRCmwFYxxGXkh8aKl+TCgVDf+wW8wcbaDcuI7rd44HUKVbUGuaHSetbMnwsqyvEojv5ZPDb9I zHqTkKR7C3d9+NnN9ztrMYT2g6MSApOkx5mVTHSGmVKzQ72JSIwaecqqKv5gNydfrJ1tZkYurdL /cU6nOFAbElmxmhf4Mbbuh3W3B4JXrHpDKnOe8MPBMEVnauT X-Received: by 2002:a05:6830:7101:b0:727:ccd:4a80 with SMTP id 46e09a7af769-72712037a98mr15179429a34.3.1740018361453; Wed, 19 Feb 2025 18:26:01 -0800 (PST) X-Google-Smtp-Source: AGHT+IH+1pTLV2juz3XWnrP6l8YrlhAGKreyIq4mE3Rwt2QTzHiDJTVBAxIgpErDaTCZyIH4jq56VQ== X-Received: by 2002:a05:6830:7101:b0:727:ccd:4a80 with SMTP id 46e09a7af769-72712037a98mr15179412a34.3.1740018361182; Wed, 19 Feb 2025 18:26:01 -0800 (PST) Received: from ?IPV6:2601:188:c100:5710:627d:9ff:fe85:9ade? ([2601:188:c100:5710:627d:9ff:fe85:9ade]) by smtp.gmail.com with ESMTPSA id 46e09a7af769-7272e96bc2csm1720420a34.54.2025.02.19.18.25.59 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 19 Feb 2025 18:26:00 -0800 (PST) From: Waiman Long X-Google-Original-From: Waiman Long Message-ID: <92c9b82b-2873-47af-a4ff-7e2f95f227d6@redhat.com> Date: Wed, 19 Feb 2025 21:25:58 -0500 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/2] hung_task: Show the blocker task if the task is hung on mutex To: "Masami Hiramatsu (Google)" , Steven Rostedt Cc: Waiman Long , Peter Zijlstra , Ingo Molnar , Will Deacon , Andrew Morton , Boqun Feng , Joel Granados , Anna Schumaker , Lance Yang , Kent Overstreet , Yongliang Gao , Tomasz Figa , Sergey Senozhatsky , linux-kernel@vger.kernel.org, Linux Memory Management List References: <173997003868.2137198.9462617208992136056.stgit@mhiramat.tok.corp.google.com> <173997004932.2137198.7959507113210521328.stgit@mhiramat.tok.corp.google.com> <20250219112308.5d905680@gandalf.local.home> <0fa9dd8e-2d83-487e-bfb1-1f5d20cd9fe6@redhat.com> <20250219152435.35077ac3@gandalf.local.home> <20250220080908.fc1494f0f7c611b48fbe0f8b@kernel.org> <20250219185810.57561c69@gandalf.local.home> <20250220110800.42ce6b1b8e94a3b998d533a5@kernel.org> In-Reply-To: <20250220110800.42ce6b1b8e94a3b998d533a5@kernel.org> X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: o5cmE0SMrIVLkxf7FiyKf72efkyLZ5jqfqetaxUSic8_1740018361 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: E971E40002 X-Stat-Signature: ddu9onuiae4onc3hxiaj9bjikxjsiuoq X-HE-Tag: 1740018363-763326 X-HE-Meta: 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 mZiW7JgX 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000123, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 2/19/25 9:08 PM, Masami Hiramatsu (Google) wrote: > On Wed, 19 Feb 2025 18:58:10 -0500 > Steven Rostedt wrote: > >> On Thu, 20 Feb 2025 08:09:08 +0900 >> Masami Hiramatsu (Google) wrote: >> >>> So something like this? >>> >>> unsigned int block_flags; >>> union { >>> struct mutex *mutex; >>> struct rwsem +rwsem; >>> struct rtmutex *rtmutex; >>> } blocked_on; >>> >>> enum { >>> BLOCKED_ON_MUTEX; >>> BLOCKED_ON_RWSEM; >>> BLOCKED_ON_RTMUTEX; >>> BLOCKED_ON_IO; >>> } block_reason; >>> >>> For the safety, we may anyway lock the task anyway, but that is the >>> same as stacktrace. >> Why not make it into a single entity? >> >> struct blocked_on { >> unsigned int flags; >> union { >> struct mutex *mutex; >> struct rwsem *rwsem; >> struct rtmutex *rtmutex; >> } blocked_on; >> }; > Yes, and we also merge current mutex_waiter too. I don't think we should merge mutex_waiter as it contains additional fields that are not useful to others. We don't want enlarge the size of task_struct unnecessarily. Cheers, Longman