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=-5.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 B7933C07E9B for ; Wed, 7 Jul 2021 12:43:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 934B061CB2 for ; Wed, 7 Jul 2021 12:43:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231624AbhGGMqY (ORCPT ); Wed, 7 Jul 2021 08:46:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44926 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231539AbhGGMqV (ORCPT ); Wed, 7 Jul 2021 08:46:21 -0400 Received: from mail-il1-x134.google.com (mail-il1-x134.google.com [IPv6:2607:f8b0:4864:20::134]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 45FE1C06175F for ; Wed, 7 Jul 2021 05:43:41 -0700 (PDT) Received: by mail-il1-x134.google.com with SMTP id f12so2450169ils.11 for ; Wed, 07 Jul 2021 05:43:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20150623.gappssmtp.com; s=20150623; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=PCvrCrmMvV1laLdUNmLRNpsahOO3ZtiZEh8I1JSMjmU=; b=K4LlkuzRMFBUdbHKBCNLoOpYTHSubx5w/H7U7MhiBK/I2ztFR/cxtK13DFo+vjvYaj ssaqk61/c8xaRIMO1od68Yi0CM9y8/7K/+AsFoXCekQQhWDhQEV1AF+NFlbp6EJGKhJb cqKVvBXE1ejpnYrb+NwjI4JW95HWbn92Pnq3MEQFq90khpNVRBZ1d4aHYDHKNeHZKU06 eOP9Fyd5DeWVLBliqkB61MJ7BSkFeBHkHrjQdeH3RbGd1gIOaamkv/JfsJtdBM5ajpiz q4uJkKOr7CYk1EIztJK2dlpzOCxtjcB7xQxHekrLIdkA7dBUZPHVCA1YPs8fvMU3KmzC 3vzw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=PCvrCrmMvV1laLdUNmLRNpsahOO3ZtiZEh8I1JSMjmU=; b=QlQ8/uSAbFu/9o4PVVWcZgElk/Cocb3s75NBO4dnydxB77PT662zr2RkJvJRUBEhAX ynLDfBLJCx/K7XrQnLERdpE94dn9MfpQhyjNs3vsBx3+90nFqmKJCxrggHVJI8BQkSvw K0hV1QvRJGKf9OWvM2Ca5vN2RU7s4Xwnp5E5RuuIxL7Mm/5FoXXz2OZVr4LL+tjkgSeQ 8ZfvyjjnMWby23JyCWlS6Wr0d8V7RfVTBqH/GEwSzj1y0Sw44mpQtmmSyOe44ttiSx6/ b9gfUxGzm1SJQTrw35SVxFckSd9p6M/ehD71Fx0NvG3tUx3hOFkEz65ZVozftJJBOupQ E4Gg== X-Gm-Message-State: AOAM531gq/TuxWprmxDuJAaotlHesrmyVIJ/XiynOjoxTlBkpqOD8XoM 1OTtSQ357huHBfIMHtQ28r9IzE2rlJ7HKA== X-Google-Smtp-Source: ABdhPJxEeAmthCg/FZBw7hIDzkyE5Y0uETAIeMrfNiY6WSlFvkZ02VadtzRpxgHf+N7sncAk7TFbWA== X-Received: by 2002:a92:3209:: with SMTP id z9mr18409959ile.115.1625661820459; Wed, 07 Jul 2021 05:43:40 -0700 (PDT) Received: from [192.168.1.134] ([198.8.77.61]) by smtp.gmail.com with ESMTPSA id q8sm11081038iot.30.2021.07.07.05.43.39 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 07 Jul 2021 05:43:40 -0700 (PDT) Subject: Re: [PATCH v3] block: fix the problem of io_ticks becoming smaller To: brookxu Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org References: <1625521646-1069-1-git-send-email-brookxu.cn@gmail.com> From: Jens Axboe Message-ID: <5d79fd9f-2dda-dc62-8298-393ee223fc0d@kernel.dk> Date: Wed, 7 Jul 2021 06:44:03 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <1625521646-1069-1-git-send-email-brookxu.cn@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 7/5/21 3:47 PM, brookxu wrote: > From: Chunguang Xu > > On the IO submission path, blk_account_io_start() may interrupt > the system interruption. When the interruption returns, the value > of part->stamp may have been updated by other cores, so the time > value collected before the interruption may be less than part-> > stamp. So when this happens, we should do nothing to make io_ticks > more accurate? For kernels less than 5.0, this may cause io_ticks > to become smaller, which in turn may cause abnormal ioutil values. > > v3: update the commit log > v2: sorry, fix compile error due to the missed ')' The version log goes below the '---' in the email, not in the commit message. I fixed that up. Applied for 5.14, thanks. -- Jens Axboe