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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A86D8C6FD18 for ; Tue, 18 Apr 2023 14:11:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231891AbjDROLi (ORCPT ); Tue, 18 Apr 2023 10:11:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49426 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231156AbjDROLf (ORCPT ); Tue, 18 Apr 2023 10:11:35 -0400 Received: from mail-wm1-x330.google.com (mail-wm1-x330.google.com [IPv6:2a00:1450:4864:20::330]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 42148146C5 for ; Tue, 18 Apr 2023 07:11:31 -0700 (PDT) Received: by mail-wm1-x330.google.com with SMTP id o6-20020a05600c4fc600b003ef6e6754c5so13620739wmq.5 for ; Tue, 18 Apr 2023 07:11:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=layalina-io.20221208.gappssmtp.com; s=20221208; t=1681827090; x=1684419090; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=WE+IDjNLmYXyAL5RgYEYkpXIxD65+3kxB5fg3jMT7Z8=; b=dprNceqvHv7ehj1AFyq6IVZuyA050VxzOgnpjffjlO0ZTrtbaukOxmEs6ZwMyph6DF F/S8P85T1AvENM5C6pZFvN7Z0PNWVxad+nEtZZBhxHYLj39ZchKFYYXEoBvPG3wOZuTp pgja402GMS0SJvQwxvnk3iSldEhFdUttDgOKnjLRNUX448+VVk/fUiHEbl+Z8/uEmvlm Oof8NAaozlK6EX/U9LAROF5sy5j74fSWC08pHqswc0eg6oqwrWCbZ0vtRQZb5+0kY7ov A20xhQ1MrM9+VMW1q6b6ypOU1eP1gwMu71zfJF11JCrA/zGZF4r0MA/5mhiAdSZEkWLi nQpQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1681827090; x=1684419090; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=WE+IDjNLmYXyAL5RgYEYkpXIxD65+3kxB5fg3jMT7Z8=; b=A+g6Fj3D7LYoDydn5EgwCIAtvSpg3T0H0t70jtDYwslWhA/7B0PDAkVBJxPzNaRzAM eGqJ17jB7HqzwYwVWJJg/+dimtqssGp6EAHLa0ogrES9C8RrsVqHwWT9stPguykEb4k9 55ga2ibdHw7w1q0biu7ej/U2INb+ri5tMtIt0BtovNM0rInJ7AR09yMIO8Yq0Zy7PO3X kP+QynTSGqRJsB6DPRkUgvebWRrITbhfcebcveXi7JuT+5lpCw7LkDrUaqdHLf/x0HR2 5+URd2wn9WZwBWjKEjNsSA7t64/YnBw2AyZfBH/XUXz3wE8fXzhCxxyDuHXFgz6NlnfH narA== X-Gm-Message-State: AAQBX9fKnX6bex+Eegtr6NDTx8sHI9ndsna9y+znhlOH2Q58KAS72o1F FDkadamOXrju4Thru8eIyJ1cfuVAZXZWKuxq7Xo= X-Google-Smtp-Source: AKy350ajzjOuf3arxENo4exaQjQnAw/S1q2RJh78GqT856IO2LFlhTXvpLQPIXl+yESeB2+GEmDxHw== X-Received: by 2002:a1c:f719:0:b0:3f0:a9b1:81e0 with SMTP id v25-20020a1cf719000000b003f0a9b181e0mr13419456wmh.19.1681827089702; Tue, 18 Apr 2023 07:11:29 -0700 (PDT) Received: from airbuntu ([104.132.45.106]) by smtp.gmail.com with ESMTPSA id iw1-20020a05600c54c100b003f174cafcdasm5048524wmb.7.2023.04.18.07.11.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 18 Apr 2023 07:11:29 -0700 (PDT) Date: Tue, 18 Apr 2023 15:11:27 +0100 From: Qais Yousef To: Juri Lelli Cc: Peter Zijlstra , Ingo Molnar , Waiman Long , Tejun Heo , Zefan Li , Johannes Weiner , Hao Luo , Dietmar Eggemann , Steven Rostedt , linux-kernel@vger.kernel.org, luca.abeni@santannapisa.it, claudio@evidence.eu.com, tommaso.cucinotta@santannapisa.it, bristot@redhat.com, mathieu.poirier@linaro.org, cgroups@vger.kernel.org, Vincent Guittot , Wei Wang , Rick Yiu , Quentin Perret , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Sudeep Holla Subject: Re: [PATCH 0/6] sched/deadline: cpuset: Rework DEADLINE bandwidth restoration Message-ID: <20230418141127.zbvsf7lwk27zvipt@airbuntu> References: <20230329125558.255239-1-juri.lelli@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20230329125558.255239-1-juri.lelli@redhat.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/29/23 14:55, Juri Lelli wrote: > Qais reported [1] that iterating over all tasks when rebuilding root > domains for finding out which ones are DEADLINE and need their bandwidth > correctly restored on such root domains can be a costly operation (10+ > ms delays on suspend-resume). He proposed we skip rebuilding root > domains for certain operations, but that approach seemed arch specific > and possibly prone to errors, as paths that ultimately trigger a rebuild > might be quite convoluted (thanks Qais for spending time on this!). > > To fix the problem > > 01/06 - Rename functions deadline with DEADLINE accounting (cleanup > suggested by Qais) - no functional change > 02/06 - Bring back cpuset_mutex (so that we have write access to cpusets > from scheduler operations - and we also fix some problems > associated to percpu_cpuset_rwsem) > 03/06 - Keep track of the number of DEADLINE tasks belonging to each cpuset > 04/06 - Create DL BW alloc, free & check overflow interface for bulk > bandwidth allocation/removal - no functional change > 05/06 - Fix bandwidth allocation handling for cgroup operation > involving multiple tasks > 06/06 - Use this information to only perform the costly iteration if > DEADLINE tasks are actually present in the cpuset for which a > corresponding root domain is being rebuilt > > With respect to the RFC posting [2] > > 1 - rename DEADLINE bandwidth accounting functions - Qais > 2 - call inc/dec_dl_tasks_cs from switched_{to,from}_dl - Qais > 3 - fix DEADLINE bandwidth allocation with multiple tasks - Waiman, > contributed by Dietmar > > This set is also available from > > https://github.com/jlelli/linux.git deadline/rework-cpusets Is this just waiting to be picked up or still there's something to be addressed still? Thanks! -- Qais Yousef