From patchwork Mon Apr 8 14:39:34 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paolo Valente X-Patchwork-Id: 161937 Delivered-To: patch@linaro.org Received: by 2002:a02:c6d8:0:0:0:0:0 with SMTP id r24csp3764988jan; Mon, 8 Apr 2019 07:39:56 -0700 (PDT) X-Google-Smtp-Source: APXvYqxbww5hmj6YzPclZZMeibPjJN74bPMuyZ9LhDEceq2c1ra1MmvDAtAlODC9h+JlC7Nk0hKf X-Received: by 2002:a63:7943:: with SMTP id u64mr28535765pgc.91.1554734396041; Mon, 08 Apr 2019 07:39:56 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1554734396; cv=none; d=google.com; s=arc-20160816; b=qmP8HGfeT7LFgHHSSVOpYZDd6rjxxzcQQ2FWBECy1IPrVZ2Y3yhstPWZ7+W06w7SZQ pTMDai/RdDn6zK2jKCoyzJM+oIQSpS0TbMd5ZOOVSCD4+pwJeQ8gQFlE8uzIlL7UZcED 1yA0af+12gB4KLgsm/U7aqkjOIL9eZUmvXrG/C0ev2polVQRjDco/Z/e66iXi5uxe0aN mIyh6LBw9IcIPxswytDHrHZUPMUT+JXm0sY9GCjSs4cYjTfmFqb5OxdC85VkjQIrOQ/k RTdDaiZJ5k+miI3xCQ8zBAwSv0KGnsF+HgsYnPDCQI+nsvOKjCiK220IEbBp0Q5yjEvc x7TQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding:mime-version :message-id:date:subject:cc:to:from:dkim-signature; bh=u+vmddB8EPhLmq89u2MDX4J7x+h19OXK3BtBDxYPEZc=; b=x1XOgl4vrRxlykuGQ0YlcJR5EUn1EiNDlAvL8fiH/+vwJo+VT3JIr3UwsJlObXf1vU rZm2of8PTnv/Vo03E4pXkr/G1NAu2GCme0TsjPSUXpneNzkCU5xG1RT3979X55m27gg7 NQgcvdNxnNJm3FdtgcYdv0jYbsTRKK3XIFjYKFHa3+HkMFru8oaaQ5HcPHna6LViOPFG VtNOfgmRD5JXOEN3hf5JipreXIOrYIJ6YiCef6400DEneho8IQWoPADoM77abvRxhDHo DjsACc+GQd3WYgo2MFfC/HpNYNtN5eEyJYrddyHDxtXrr4SjV9+zwpLQlJLeRM4eZY2z INcQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@linaro.org header.s=google header.b=WwJPw8xA; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linaro.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id f2si26138350pgi.61.2019.04.08.07.39.55; Mon, 08 Apr 2019 07:39:56 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@linaro.org header.s=google header.b=WwJPw8xA; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linaro.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727113AbfDHOjy (ORCPT + 31 others); Mon, 8 Apr 2019 10:39:54 -0400 Received: from mail-wm1-f67.google.com ([209.85.128.67]:54055 "EHLO mail-wm1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726766AbfDHOjx (ORCPT ); Mon, 8 Apr 2019 10:39:53 -0400 Received: by mail-wm1-f67.google.com with SMTP id q16so14680506wmj.3 for ; Mon, 08 Apr 2019 07:39:52 -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:mime-version :content-transfer-encoding; bh=u+vmddB8EPhLmq89u2MDX4J7x+h19OXK3BtBDxYPEZc=; b=WwJPw8xAEIceR/RAgSlJfvmVrzLFsNxBW7XVR0W5p+8vhWSrJKspLoG+sJf0kL8acZ TYS58O94CPHohA6nEgo80lm9PkQJ9PhZq+V6kn75fE1CNdTE1cmY0A8GCUOzFXYhQz3/ txc0lXgqfF7wyqJ6yfBfOrMiyVeW0p0ze1SY1FjRMrdiNH9T2nI+PicPBLGa+ZO2u2nN RCWdA/qxpm468U0baLl5yMd9SkgvE3Ls54jh7Yty8zv8KWvczWaIONOB9sT74jaqJMGp 8KUex0dG8zUGF2vmo65XmMcKr18mMQTtkQ0FgiD+Wnkzd3zS46QLndD19TybUQ6xmZd6 6Baw== 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:mime-version :content-transfer-encoding; bh=u+vmddB8EPhLmq89u2MDX4J7x+h19OXK3BtBDxYPEZc=; b=KH+P1iQYe4kDYjnhuNg4n7NOmUwZcweM9zwhIKYcbSIzd+9cWX/VUUiiZPy/aWpu0e DnKJ1hclDVxPU/JvDjX1VaLlte1UcAc2tswJWBOpJ56dgnyvnh49iTFs2ZlsewCQ7RcT 0tF0oyCSK/oS4YtyEvrUenJ8ySCahlpIjO1unrtVV7KnGOjLJxCELPNNk7OAiqbqvlF1 rY36ChYvAbrdEia698Fn6T2nt67+IxO1rIdq3lLC2TtsXD+GJQOQkSZKHlB3+xDARNPm +jvd1VocOcdiKlFV/jSv8EF7jAajzN135dTAB7awI5+qmXPqsYNA5lAyl8Zik5eu3f/5 RCSg== X-Gm-Message-State: APjAAAVDL80trU7MN099mALnVeDVplDVMJEh/mwr6Rb6TpJPhvCeg1Ga FBLtj/aJuaxI8I+Kojkc/dIAwEN3x1LDIA== X-Received: by 2002:a1c:e90f:: with SMTP id q15mr17467575wmc.1.1554734391893; Mon, 08 Apr 2019 07:39:51 -0700 (PDT) Received: from localhost.localdomain ([88.147.51.116]) by smtp.gmail.com with ESMTPSA id r196sm15113852wmf.22.2019.04.08.07.39.50 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 08 Apr 2019 07:39:51 -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 0/1] bfq: remove prefixes from cgroup filenames Date: Mon, 8 Apr 2019 16:39:34 +0200 Message-Id: <20190408143935.9062-1-paolo.valente@linaro.org> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When bfq was merged into mainline, there were two I/O schedulers that implemented the proportional-share policy: bfq for blk-mq and cfq for legacy blk. bfq's interface files in the blkio/io controller have the same names as cfq. But the cgroups interface doesn't allow two entities to use the same name for their files, so for bfq we had to prepend the "bfq" prefix to each of its files. However no legacy code uses these modified file names. This naming also causes confusion, as, e.g., in [1]. So we tried to propose a solution to enable entities to share interface files for identical parameters [2]. But our solution didn't convince Tejun, and we got stuck. Fortunately, now cfq has gone with legacy blk, so there is no need any longer for prefixes in (the never used) bfq names. In view of this fact, here's an alternative patch, which simply removes these prefixes, thereby enabling legacy code to truly use the proportional share policy in blk-mq. This postpones the problem of sharing common interface files, to when, e.g., some new proportional-share policy gets proposed. Paolo [1] https://github.com/systemd/systemd/issues/7057 [2] https://lwn.net/ml/linux-block/20181119103424.3853-1-paolo.valente@linaro.org/ Angelo Ruocco (1): block, bfq: delete "bfq" prefix from cgroup filenames block/bfq-cgroup.c | 46 +++++++++++++++++++++++----------------------- 1 file changed, 23 insertions(+), 23 deletions(-) -- 2.20.1