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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 475C3C4332F for ; Tue, 13 Dec 2022 19:31:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236828AbiLMTbF (ORCPT ); Tue, 13 Dec 2022 14:31:05 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41356 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236267AbiLMTbC (ORCPT ); Tue, 13 Dec 2022 14:31:02 -0500 Received: from mail-pf1-x431.google.com (mail-pf1-x431.google.com [IPv6:2607:f8b0:4864:20::431]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CCC9E24085; Tue, 13 Dec 2022 11:31:01 -0800 (PST) Received: by mail-pf1-x431.google.com with SMTP id n3so2904545pfq.10; Tue, 13 Dec 2022 11:31:01 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:sender:from:to:cc:subject:date:message-id :reply-to; bh=sXb/rEJk2v1xayTt6fq4DLeZdX5JWv1TpuzsNKAsI7M=; b=G7J7io0xWPaTvvK6zYRTl01FHKEjCE7q/Jaq0JD7R1g3OdahdIZtirguReRInIrPRH lZsfSIG+8+OSKwrxDm0SlrqyJmOeSXBDZrO8SkfI4g6JjRukQH28HHKsxVX/gSYqaybD hxxQOSwBU4s3Sc7AvEyaQxh8DY45WGklrYMAn2GHRlP8xHqIqTs1JTT5nO6YSg9E9p2w fic1D5sGqkASXcthzYQanLnBIebq2BxRY4h0k/r/Sbgjb+opKe973QztrDdQbHiBgwbJ Yg/P5MaegIvmBAoR2/1zusmab90D83KH1vTve3IBK1wCcxqZ9z0CYdq5ekniAUS5kP7n q8wA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:sender:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=sXb/rEJk2v1xayTt6fq4DLeZdX5JWv1TpuzsNKAsI7M=; b=19d8AlXAXm9gpJtZa3xBPfL6SQsQUhLHclLDmW9Jdnckq/muVFYE6d7YYQmjXytd4Q ysMwPrcMDf5TSCavn8omVsCFGbn9ckGBnC89Or0DJjgmOiNLtxif4ivO8eSqg3yOQsQR eIsoDQOdJmmXTG94KD2Frk9a3cj9Xaw8YQIHm9VHRaK+R+S0D1s9u0hjuLRKBBKlFSCU x/PmvLhB9tTFamB2dIjpaOFbn5MDiEizqWIG6hsbCP6ABF+/PjSke2JmtLBCG5E8e06O V9HXdp/aZH6LqaBuiTHv+g230KKGyHp1HNjNCmdA3dZOFK57HmsCIWzqahJ4JwS2I97H Bobg== X-Gm-Message-State: ANoB5pl2uenaJlEcTY8JK8g3u6SK6h/DN7R/jdQCZLG8xCL8oZkkGFh9 yifdUGneRhxUZKd6Sq8ZTmk= X-Google-Smtp-Source: AA0mqf4LR0w9Q2cfjZcReFSGVhRaqHyqmcRJT4oMpOm+Bbkp1P5i0Ew5juN6Qehq6v8vhXbEJ9/Biw== X-Received: by 2002:a05:6a00:4482:b0:576:95ec:bc93 with SMTP id cu2-20020a056a00448200b0057695ecbc93mr20756659pfb.23.1670959861145; Tue, 13 Dec 2022 11:31:01 -0800 (PST) Received: from localhost ([2620:10d:c090:400::5:c415]) by smtp.gmail.com with ESMTPSA id i63-20020a62c142000000b00572198393c2sm7986815pfg.194.2022.12.13.11.31.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 13 Dec 2022 11:31:00 -0800 (PST) Sender: Tejun Heo Date: Tue, 13 Dec 2022 09:30:59 -1000 From: Tejun Heo To: Waiman Long Cc: Jens Axboe , Josef Bacik , Zefan Li , Johannes Weiner , Andrew Morton , cgroups@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Michal =?iso-8859-1?Q?Koutn=FD?= , "Dennis Zhou (Facebook)" Subject: Re: [PATCH-block v3 2/2] blk-cgroup: Flush stats at blkgs destruction path Message-ID: References: <20221213184446.50181-1-longman@redhat.com> <20221213184446.50181-3-longman@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221213184446.50181-3-longman@redhat.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Dec 13, 2022 at 01:44:46PM -0500, Waiman Long wrote: > + /* > + * Flush all the non-empty percpu lockless lists so as to release > + * the blkg references held by those lists which, in turn, may > + * allow the blkgs to be freed and release their references to > + * blkcg speeding up its freeing. > + */ Can you mention the possible deadlock explicitly? This sounds more like an optimization. Thanks. -- tejun