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=-2.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,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 89900C432C3 for ; Wed, 13 Nov 2019 22:46:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 731332063A for ; Wed, 13 Nov 2019 22:46:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=kernel-dk.20150623.gappssmtp.com header.i=@kernel-dk.20150623.gappssmtp.com header.b="fd+FP+ka" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726452AbfKMWqn (ORCPT ); Wed, 13 Nov 2019 17:46:43 -0500 Received: from mail-pf1-f196.google.com ([209.85.210.196]:35603 "EHLO mail-pf1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726303AbfKMWqn (ORCPT ); Wed, 13 Nov 2019 17:46:43 -0500 Received: by mail-pf1-f196.google.com with SMTP id q13so2665222pff.2 for ; Wed, 13 Nov 2019 14:46:41 -0800 (PST) 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=gbZCSwDYFj658984dBBc49SXiSwvrurgg24kQZJ6lFY=; b=fd+FP+kaxoSwrip2+b5Fxa/rzbSp5GGswoJOIgceEu0KmZo2a+RyMB85R4A8Dvwx35 Dx413diQ2oQUo3LaPTFUDalSdf1Fmk0IVUCNkje1AkzpKU26d4ir291SI74KHfOr+yqX viyo73Ib4Hod+og3pqvlwDjfUrWaTFIwnsOzzV4iOydv5Zl9X9gzBj2HzAO8ZlUdNkE6 Xs9RAUEcKet9YwBxfPy9OF3AqnNZT5Dc1kERxZGM6Ehcqohbwa6osRWMR08OYs0/1KDc Jp671fnbIZKLocWcJpyIsPIr3cvy4vN2De9HsOrSh9Zq5lh0tiYWAYsewSennd0eVaS1 oI1A== 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=gbZCSwDYFj658984dBBc49SXiSwvrurgg24kQZJ6lFY=; b=PZ8OFUkUds2ArE5Rb+ORhmiz4xrXkLYHazqWxSU0FoXK5f1hcEPg6wWPZFmrZiyvQ9 a2DsyYew0TmjhW23fOLqGIvyKnS1fE5LDD2AJF4W9cFiEy1Dsc1we1yqhLfqiz6JVQXk znMXUWyLjirk4QmRrIb6Hk8hg4Nx9JLPH8g1s+k6baLmMxSkJUjg4tq0u0NR1C67/fGR 4H3ZgqZ2IYK2rTw4sdRjBvZdxoz6sxhCuWTewhzVyCRzIMKgB1B1b20mVH7Sl9PCi9R7 xm5z8kZRimPMsUbAoiV4SGm0rpY8/NLtXNukgusVnjH//nB3som1v/wSzQfazZh9C0zi GddQ== X-Gm-Message-State: APjAAAVz7M8WMb3baXPYIofmJTrH5YTTCLlnuVG/oOQ7xt5cLiwx+hqf b7MGhMTXaZdi+L6qe8kG1CwfLSwvfUI= X-Google-Smtp-Source: APXvYqxZ+RguZpVb/kuBox86s39GRqt54LRO8R8B8gFUzQ7R9ksUKg7BQlYiSEYEST795AfMqH1KNA== X-Received: by 2002:a17:90a:fc85:: with SMTP id ci5mr8428092pjb.17.1573685200779; Wed, 13 Nov 2019 14:46:40 -0800 (PST) Received: from [192.168.1.182] ([66.219.217.79]) by smtp.gmail.com with ESMTPSA id v10sm3465583pgr.37.2019.11.13.14.46.38 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 13 Nov 2019 14:46:39 -0800 (PST) Subject: Re: [PATCH BUGFIX] block, bfq: deschedule empty bfq_queues not referred by any process To: Paolo Valente , Oleksandr Natalenko Cc: linux-block , linux-kernel , Ulf Hansson , linus.walleij@linaro.org, bfq-iosched@googlegroups.com, Chris Evich , Patrick Dung , Thorsten Schubert References: <20191112074856.40433-1-paolo.valente@linaro.org> <2FB3736A-693E-44B9-9D1F-39AE0D016644@linaro.org> <65fc0bffbcb2296d121b3d5a79108e76@natalenko.name> <5773ff54421ccf179ef57d96e19ef042@natalenko.name> <69B451DE-B04B-4E0E-9464-826C4A7619AD@linaro.org> From: Jens Axboe Message-ID: <8f77fb4e-a49b-4ddc-8756-e08b030dd7e4@kernel.dk> Date: Wed, 13 Nov 2019 15:46:37 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <69B451DE-B04B-4E0E-9464-826C4A7619AD@linaro.org> Content-Type: text/plain; charset=windows-1252 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/13/19 10:42 AM, Paolo Valente wrote: > > >> Il giorno 13 nov 2019, alle ore 16:01, Oleksandr Natalenko ha scritto: >> >> On 13.11.2019 15:25, Oleksandr Natalenko wrote: >>> I didn't try to switch schedulers, but what I see now is once the >>> system is able to boot with BFQ, the I/O can still hang on I/O burst >>> (which for me happens to happen during VM reboot). >>> This may also not hang forever, but just slow down considerably. I've >>> noticed this inside a KVM VM, not on a real HW. >> >> Possible call traces: > > Ok, you may have given me enough information, thank you very much. > > Could you please apply the attached (compressed) patch on top of my > offending patch? For review purposes, here is the simple change: FWIW, I dropped the previous patch. -- Jens Axboe