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=-3.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, USER_AGENT_GIT autolearn=ham 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 449E6C4321D for ; Thu, 16 Aug 2018 16:52:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0043720C0D for ; Thu, 16 Aug 2018 16:52:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=linaro.org header.i=@linaro.org header.b="fGHLAMAM" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0043720C0D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730843AbeHPTvi (ORCPT ); Thu, 16 Aug 2018 15:51:38 -0400 Received: from mail-wr1-f65.google.com ([209.85.221.65]:44338 "EHLO mail-wr1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727285AbeHPTve (ORCPT ); Thu, 16 Aug 2018 15:51:34 -0400 Received: by mail-wr1-f65.google.com with SMTP id r16-v6so4732988wrt.11 for ; Thu, 16 Aug 2018 09:51:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id; bh=kAJN5fxC24ZODwvl+eKV5x4mhAs5Fw7VBfu8pF7El8s=; b=fGHLAMAMm2lu4C8wbEa9LebpuT0CWFBu8Dl2kK/eZX0j4PU7yubwoMjcXb2/l76E68 url8VIG0TUwC7auEYiMr006uz+2nxGfKfIOTQL9YYHzLD3VnfZsvw17xw+NjiPY41s1o XaiDFv07Bb2iWxRqI2up33sXAQZF8mvSVmgpQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=kAJN5fxC24ZODwvl+eKV5x4mhAs5Fw7VBfu8pF7El8s=; b=ECbCcY5ntgAj1pyyjQHDf1ap+scnWkiLQNrul5WPxRZjOinfWvN6LAriPVgnqq8apm wmdZ2BPpm9+snhQemXfgrQKNn0t8P1/nLIS8CsnV/BMDES/vO723uDHBHWXTjIAKA5Xb likdFblrreXf8Hng5wi9EcvBQVBIALo95TCBTPdanQnqmr2OUdjQY1iiUsjukJm6QxlX 4lE26yl145qtf+/wMRzOBWmdRznHY4Q5/3QBiOEq4Rjj6VAHN3b7rVYDANT4trglU94S wDkQVIEXdFODt9Tc9zC5vVrqeY5JXg3zdHKViyjfnhNKJmD6XXD/Hlvp0WH7RB6D2WpP O85g== X-Gm-Message-State: AOUpUlF7S5BV5o+O/Toai1sPran3YyI/iW70lmFPleuEyBKZSEMGLnsl oSy8tqIwGvBGDe/vN537y3u/7g== X-Google-Smtp-Source: AA+uWPwrIXEOxfwHQ1ScvvFjEAlbdtaxTUZ6ObwN+omTBKgZLK8CpHMh2nF5cbOoqF8dyCzzROSWsQ== X-Received: by 2002:adf:f1c8:: with SMTP id z8-v6mr2412002wro.214.1534438315762; Thu, 16 Aug 2018 09:51:55 -0700 (PDT) Received: from localhost.localdomain (146-241-5-103.dyn.eolo.it. [146.241.5.103]) by smtp.gmail.com with ESMTPSA id o3-v6sm30036180wrj.31.2018.08.16.09.51.54 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 16 Aug 2018 09:51:55 -0700 (PDT) From: Paolo Valente To: Jens Axboe Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, ulf.hansson@linaro.org, linus.walleij@linaro.org, broonie@kernel.org, bfq-iosched@googlegroups.com, oleksandr@natalenko.name, Paolo Valente Subject: [PATCH BUGFIX/IMPROVEMENT 0/4] bfq: two fixes and one improvement related to I/O control Date: Thu, 16 Aug 2018 18:51:14 +0200 Message-Id: <20180816165118.17402-1-paolo.valente@linaro.org> X-Mailer: git-send-email 2.16.1 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Jens, while working a little bit on cgroups I/O control, I found two nasty bugs in bfq. They break bandwidth control in simple configurations with one-process groups. These bugs are fixed by the first two patches in this series. These fixes improved I/O control so much, that I could reduce the write overcharge factor, used by bfq to counter write-induced issues. This reduction is performed by the third patch. The fourth patch contains a little code improvement I made in a function that has to do with I/O control. I hope we are still in time for 4.19. Thanks, Paolo Paolo Valente (4): block, bfq: readd missing reset of parent-entity service block, bfq: always update the budget of an entity when needed block, bfq: reduce write overcharge block, bfq: improve code of bfq_bfqq_charge_time block/bfq-iosched.c | 54 +++++++++++++++++++++++++++++++++++++++-------------- block/bfq-wf2q.c | 22 +++++++++++----------- 2 files changed, 51 insertions(+), 25 deletions(-) -- 2.16.1