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=-0.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 07F7CC31E45 for ; Thu, 13 Jun 2019 16:45:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D1C0E215EA for ; Thu, 13 Jun 2019 16:45:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="DF7lFpNI" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730388AbfFMQpM (ORCPT ); Thu, 13 Jun 2019 12:45:12 -0400 Received: from mail-wm1-f67.google.com ([209.85.128.67]:34912 "EHLO mail-wm1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730382AbfFMGKo (ORCPT ); Thu, 13 Jun 2019 02:10:44 -0400 Received: by mail-wm1-f67.google.com with SMTP id c6so8764146wml.0 for ; Wed, 12 Jun 2019 23:10:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:message-id:mime-version:subject:date:in-reply-to:cc:to :references; bh=nIFKJpfyK2DxoQfFQcfYz4XDj8g98HiIMkXp7eU/vOE=; b=DF7lFpNIZm11PUqgPUscuIW7PKtZToXjoi9lvl3FR1Q9DRGg14WXbYeszl5jLzlSq4 nfCCh6z1NER5WcVNsoKKSjsxwj2N5WiROdNkXxo/k0TgUFZQ0e7bSPnPTP1c/rSRBsuK pNRGCUTRwzKUWTzCnKuci7YFqe0wmVdVxQh6CmK8jxO8ELZgc3k5dfH0h3FcRHCtNLiX ycTmN8bo0zmkg19lfL4IR6qrH9K1UtpvGDs3sx0yz7HAek2Dg/nmLT2onm8pLgeYU3wr 89jR2q8+e2+5lQu1RCt9wEM2ACvXxTZoG4rxus6i6ykaemPNgDhQGCdYnc1L4MaWJHEJ WmwQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:message-id:mime-version:subject:date :in-reply-to:cc:to:references; bh=nIFKJpfyK2DxoQfFQcfYz4XDj8g98HiIMkXp7eU/vOE=; b=swVIK4CiDecUlTwRbrI5QjZNu2yXcFqbXe9NmKc2RrqGtkjVz/4v0Ep8/0bSSjl2jI 9Bj/GDt1wfbLuNgZL2OE2L6MQuCwHjlZ0kq0NEKVqSMNnjQaXqEwt3O1dWvmw3e8zmuq rL+LIvMBp/z7/1XyGSDBr0J+5Yn/ZtJluMqFvgeVR10ESDA2eRQvKhyBA2qG/Cs2x2eX lSGNYW0p7S83cCrn6qGZlwZUQ7gWs8wTgUPn6GMrvXRJPiMd1MIdQNM9W8wrLsjNtAbC 0y012lHFXlVu9VvOvo8fOe9Y0XEZTaDaCTysEXR50W9hvwRBoJaF0QmhWQ2/f7GEo1lY aeKg== X-Gm-Message-State: APjAAAW/76+Z+VPl4Cowye7s7M26UPZo/2xuPyL2e2K5OBgIypCL0ZGO T0XkQCkh6oJDUxEAtaxLBIzxjg== X-Google-Smtp-Source: APXvYqy+cl8n4hDv1iOEmh12JXvIEAJuVbxqKY/0pT+UyDt/8JbKHMem8Geo16+D7J3h9STcUoQgZA== X-Received: by 2002:a7b:c018:: with SMTP id c24mr1933499wmb.37.1560406241185; Wed, 12 Jun 2019 23:10:41 -0700 (PDT) Received: from [192.168.0.102] (88-147-71-233.dyn.eolo.it. [88.147.71.233]) by smtp.gmail.com with ESMTPSA id w14sm2179319wrt.59.2019.06.12.23.10.39 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 12 Jun 2019 23:10:40 -0700 (PDT) From: Paolo Valente Message-Id: <530F0FC2-EBE5-4417-8732-010837C18357@linaro.org> Content-Type: multipart/signed; boundary="Apple-Mail=_517D8028-653A-4641-A322-BAD7B9C9C32F"; protocol="application/pgp-signature"; micalg=pgp-sha256 Mime-Version: 1.0 (Mac OS X Mail 12.4 \(3445.104.8\)) Subject: Re: [PATCH block/for-5.2-fixes] bfq: use io.weight interface file instead of io.bfq.weight Date: Thu, 13 Jun 2019 08:10:38 +0200 In-Reply-To: <20190612133926.GN3341036@devbig004.ftw2.facebook.com> Cc: Linus Torvalds , Jens Axboe , Li Zefan , Johannes Weiner , "linux-block@vger.kernel.org" , Johannes Thumshirn , Ulf Hansson , Linus Walleij , Fam Zheng To: Tejun Heo References: <4f801c9b-4ab6-9a11-536c-ff509df8aa56@kernel.dk> <52daccae-3228-13a1-c609-157ab7e30564@kernel.dk> <90A8C242-E45A-4D6E-8797-598893F86393@linaro.org> <20190610154820.GA3341036@devbig004.ftw2.facebook.com> <20190611194959.GJ3341036@devbig004.ftw2.facebook.com> <20190611211718.GM3341036@devbig004.ftw2.facebook.com> <20190612133926.GN3341036@devbig004.ftw2.facebook.com> X-Mailer: Apple Mail (2.3445.104.8) Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org --Apple-Mail=_517D8028-653A-4641-A322-BAD7B9C9C32F Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=us-ascii > Il giorno 12 giu 2019, alle ore 15:39, Tejun Heo ha = scritto: >=20 > On Wed, Jun 12, 2019 at 09:32:07AM +0200, Paolo Valente wrote: >> Could you elaborate a little more on this? >=20 > Doesn't seem like you did. >=20 >> bfq code for setting up and handling io.weight (more precisely >> io.bfq.weight) is a copy and paste of cfq code. >=20 > Please take a look at the documentations under > Documentation/cgroup-v1/blk-iocontroller.txt and > Documentation/admin-guide/cgroup-v2.rst. >=20 I'm sorry, but I don't see what doesn't match between BFQ's and CFQ's implementations of the weight parameter. So, if you agree, let me paste the two snippets for v1 that involve weights. So maybe you can at least tell me 'here' (then I'll try the same with v2). ---------------------------------------------------------------------- mount -t tmpfs cgroup_root /sys/fs/cgroup mkdir /sys/fs/cgroup/blkio mount -t cgroup -o blkio none /sys/fs/cgroup/blkio - Create two cgroups mkdir -p /sys/fs/cgroup/blkio/test1/ /sys/fs/cgroup/blkio/test2 - Set weights of group test1 and test2 echo 1000 > /sys/fs/cgroup/blkio/test1/blkio.weight echo 500 > /sys/fs/cgroup/blkio/test2/blkio.weight -> This is exactly how you set weights with BFQ ---------------------------------------------------------------------- Details of cgroup files =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D Proportional weight policy files -------------------------------- - blkio.weight - Specifies per cgroup weight. This is default weight of the = group on all the devices until and unless overridden by per device = rule. (See blkio.weight_device). Currently allowed range of weights is from 10 to 1000. -> This is the exact implementation of the weight parameter in BFQ BFQ does not implement weight_device, but we are not talking about weight_device here. More precisely, *nothing* implements weight_device any longer in cgroups-v1, so the documentation is wrong altogether. Looking forward to your feedback, Paolo > Thanks. >=20 > -- > tejun --Apple-Mail=_517D8028-653A-4641-A322-BAD7B9C9C32F Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename=signature.asc Content-Type: application/pgp-signature; name=signature.asc Content-Description: Message signed with OpenPGP -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEpYoduex+OneZyvO8OAkCLQGo9oMFAl0B6N4ACgkQOAkCLQGo 9oOl9g//UupzRj6giFZAUQHDFrdcqt9Awx9xxl+kGzBIdD9vz8Yb8x3Rd7wQkh3o 4TKr6D3pn+bRpfpBHoKDtOE/AoY80ADAIwBp7UfEm3hX6cIxC0QcBUR3dh+Uxhjs IOpHJub0PTN5gBIn2jBkneI9BLIjzpSzBVroj3ZyR2IJNuPtYDYiPKDKRMeKMOba duvUtxSxmLmUnoGOJM55983MAJOiEP66ErrY2Ijb5jr/hs1Mb4c4kwOb/9fAbvFD wpjLaW83AglTa9AQAgpNZV0lXGxHlLrLQKKebU4iZuXw96SQUrtHtUN0m1q3RF6U REDn4Zg9XI2jp3TYm3GgLaSX0kBDOZ/GCS3nNAkJvzB1Q6AWVzthmzo0TtYsf+1Q G3RPWZ+h8zxCA7yK3VorJlr5Tj32PK7JmlCojHvKcPQHyS9VymPlxcmp6p6RuGBA glkRDHlFQRqgy9Rcgi0I1I7VJ9q+MxqaL1jOGLNMBrSO45guJR7HAwlucHQCLF7l fXeUtxH6FVcgBy9ab3B8N/JT5T4zQJm1GyOA0M7fRVdgmK4ZBXlhnu1hxBKqnBJa V1Swq4MMzwg2VLj/jlzW6k++fCeBRAHW477dmOAtfzIRwLhB3oJblv6uzwg/zN/J P6JACzPrq8bPwfho6vYrw3DZBsbxkaVakgrV1nJ+eIJdZty1kgg= =0CbJ -----END PGP SIGNATURE----- --Apple-Mail=_517D8028-653A-4641-A322-BAD7B9C9C32F--