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=-4.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 BE69BC433DF for ; Wed, 5 Aug 2020 20:12:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8454022CAF for ; Wed, 5 Aug 2020 20:12:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596658332; bh=eNpUFKziZ8BMio9ND8TxOtF+Q/qHv5pmQy9gd3/EBrw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=smCP9amZLdU4xZZJXfdLYkq3+qVi7PKl8ahASByGkes/jG/qf80/XavuFQ17ZBROI +7kszhKBtEi206OBC7U/saeKO3d/8lO1i27cvm57gSKF09uhjvowiSkb7BKMbcSgmt 4NrnaDwg2U8KRkYL9V9SAKzt7FjU1ox6GT/GlzjY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727019AbgHEUMJ (ORCPT ); Wed, 5 Aug 2020 16:12:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42728 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726398AbgHEQZe (ORCPT ); Wed, 5 Aug 2020 12:25:34 -0400 Received: from mail-qt1-x833.google.com (mail-qt1-x833.google.com [IPv6:2607:f8b0:4864:20::833]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 34857C00869E; Wed, 5 Aug 2020 07:39:17 -0700 (PDT) Received: by mail-qt1-x833.google.com with SMTP id 6so33840764qtt.0; Wed, 05 Aug 2020 07:39:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=3Ygb7Z7BelPPrQe4DRkGVgTQcrO8Cw2RRW2qRF9CXYE=; b=pp6tBE5oK4EXYLhHUerHhczMNOtv0AQryU6E7Oe9CXPImtvcqSnfK2pVeBKYdcc1CC 7iFk3ssjwttxDGUiUsDFrVfdvCHnKNaN9gPuOrD/4dmwZPH5bN7mAVNhO9Fi5Y9c0T+3 To33H16KJ+KUQ7uvE7dMCY2D096z84QZuhv2W9FJa0UawIL+mIlsQ888VL6aRgeNOKT5 SjRHQBvMdgbRimITkdG9T7VPQdtgUv4IMERoZhDt4jT6Ses9mh7jMz6K5VUuRK+Zm7vM y8HjXEPIp4tfKn3y8kWSyef94WF1XiH8pTyGWYXIZDw5g/y+uQMNSGUfIm0DXBxcj7c7 YHlA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to; bh=3Ygb7Z7BelPPrQe4DRkGVgTQcrO8Cw2RRW2qRF9CXYE=; b=TX2cn/HCQ/x0S6LGbXUEXyD2APE04VqqJOXcD4K4tTFP47Hr1n7TDSGdJVXvrTNhq3 9fAGYoEwbYflT3zjaqDBQAVGV7OKGcAlTQjs7p0miqMapQBWeMadmb4Ie17nWjTO809e R4UAun6ddHMnWQpf9xyZiNGvlsFGqEB4NGiFlmYZz621JCm4P7lVH0Gx9lum4EucK89I B4MauCLv4Rlr85e2Sv3Bz2QZHXu2EzK0sFIoQElIkBYHVtXOgLeoms0K5IwaUDgN7VwE Zw0ZNpwjLE8ACnxjPDng4Sq3W3XQaTo8eMEjuPranslWvN2meyGBb19z5O5+mWYW0Uy+ NIkg== X-Gm-Message-State: AOAM530Ljt2802O7qQjNXRroo1+teonoBuQGVmNjUA+P2xMynQkANqx8 S6ENlJfaciVV79fGH4aDxxJ2VrPo X-Google-Smtp-Source: ABdhPJwAeuq1Gw0g6oZ4EwMvVDPOBUpv5syUd1FNZfEiqH2s0XfPDKOIJt54icu/LvBGC9Z4mj/DrQ== X-Received: by 2002:ac8:f73:: with SMTP id l48mr3680579qtk.296.1596638356595; Wed, 05 Aug 2020 07:39:16 -0700 (PDT) Received: from localhost ([2620:10d:c091:480::1:fbb7]) by smtp.gmail.com with ESMTPSA id f130sm1877609qke.99.2020.08.05.07.39.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 05 Aug 2020 07:39:15 -0700 (PDT) Date: Wed, 5 Aug 2020 10:39:13 -0400 From: Tejun Heo To: Hannes Reinecke Cc: Ming Lei , James Smart , Daniel Wagner , Muneendra , linux-block , Linux SCSI List , Paolo Bonzini , Ewan Milne , mkumar@redhat.com Subject: Re: [RFC 01/16] blkcg:Introduce blkio.app_identifier knob to blkio controller Message-ID: <20200805143913.GC4819@mtj.thefacebook.com> References: <1596507196-27417-1-git-send-email-muneendra.kumar@broadcom.com> <1596507196-27417-2-git-send-email-muneendra.kumar@broadcom.com> <20200804113130.qfi5agzilso3mlbp@beryllium.lan> <20200804142123.GA4819@mtj.thefacebook.com> <227c7f27-c6c7-5db1-59ac-2dd428f5a42a@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <227c7f27-c6c7-5db1-59ac-2dd428f5a42a@suse.de> Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Hello, On Wed, Aug 05, 2020 at 08:33:19AM +0200, Hannes Reinecke wrote: > None of these are guaranteed to be either present or unique. > It's not uncommon to have VMs with more than one MAC address, and any other > unique identifier like system UUID is not required to be present. I have a really hard time seeing how this fits into block cgroup interface. The last time we did something similar (tagging from cgroup interface side) was for netcls and it ended poorly. There are basic problems with e.g. delegation as these things are at odds with everything else sharing the interface. My not-too-well informed suggestions are either building mapping somewhere in the stack or at least implement the interface where it fits better so that people who don't need app_identifier don't see them and preferably can disable them. I don't mind cgroup data structs carrying extra bits for stuff which want to make use of the cgroup tree but I'm a pretty firm nack on the proposed interface. Thanks. -- tejun