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=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,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 94DC1ECE58C for ; Fri, 11 Oct 2019 12:10:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6A966214E0 for ; Fri, 11 Oct 2019 12:10:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=digitalocean.com header.i=@digitalocean.com header.b="RBVtVI19" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728052AbfJKMKp (ORCPT ); Fri, 11 Oct 2019 08:10:45 -0400 Received: from mail-ot1-f67.google.com ([209.85.210.67]:38591 "EHLO mail-ot1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727909AbfJKMKp (ORCPT ); Fri, 11 Oct 2019 08:10:45 -0400 Received: by mail-ot1-f67.google.com with SMTP id e11so7738793otl.5 for ; Fri, 11 Oct 2019 05:10:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=digitalocean.com; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=L/oMH+7veCm4nS+KWwbQY7jv6vTOaNO0ytE/eqsALps=; b=RBVtVI19z8Zy2JrzO1/T/UqZVcHmsQ95BkRqtxA77t2yQcPyRs51igsn3V+++MEvW/ Yz8R6PBMdUJGQ4Hoo4Egj+Sf2Y6d0XyP5sHrU63lYoHWKi+0qXE3ZvN7LPGrq5pxx2mw 3xYMtBNP4ZMBuNmL4uKPLArzfUN3yLyMqmOLc= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=L/oMH+7veCm4nS+KWwbQY7jv6vTOaNO0ytE/eqsALps=; b=YGwAszSIOVlZDMt4iykWs+bDabwXNuhcxlJd2lwNInE3/yvIi2QXhu9kNHj4797k+0 uQAu5mqHr7u3Pay3GjjKwwFaTS5IPzLpgEvZoJEVLhr5nLAymKHhZ6Z9Hr60bdK6FuLY iATArhX+sCwy9Clob/tSIT/KXtdGG3fneKCZI91Ve4V9JQvkzEr7McIqAHG0SwXUfPOI eN6zoSMkUh8Osf/HPHBh7lK1Vc0lRs9Lse1p4YhQINsOiw0UqodkuF50yXsfxy6cid2U CO85pWE4t8lXdZeEsGhaAiR0wv4QDimlZ37xEtF/e09iGpbXuUFB/4c5ysMv2ZtsbVJ5 wd2w== X-Gm-Message-State: APjAAAU+lYb9KrTgtdO7iWNsfE0tqoD469cNzJMABsDTf6aw0Hh26oEI TP/etv0d4Eea6n85M3BdNGBWEClUicCos0jRp7CXxw== X-Google-Smtp-Source: APXvYqz5vscWegd3VfwRR3YpCn5eOWtYe+NMn9vThiq0DZbf5RJI92cNbfdC+/hB2ZeWW/KfaSZKQLQZTdJ6PU4STzo= X-Received: by 2002:a05:6830:22f6:: with SMTP id t22mr35902otc.237.1570795841923; Fri, 11 Oct 2019 05:10:41 -0700 (PDT) MIME-Version: 1.0 References: <20190911140204.GA52872@aaronlu> <7b001860-05b4-4308-df0e-8b60037b8000@linux.intel.com> <20190912123532.GB16200@aaronlu> <20191010135436.GA67897@aaronlu> <20191011073338.GA125778@aaronlu> <20191011114851.GA8750@aaronlu> In-Reply-To: <20191011114851.GA8750@aaronlu> From: Vineeth Remanan Pillai Date: Fri, 11 Oct 2019 08:10:30 -0400 Message-ID: Subject: Re: [RFC PATCH v3 00/16] Core scheduling v3 To: Aaron Lu Cc: Tim Chen , Julien Desfossez , Dario Faggioli , "Li, Aubrey" , Aubrey Li , Nishanth Aravamudan , Peter Zijlstra , Ingo Molnar , Thomas Gleixner , Paul Turner , Linus Torvalds , Linux List Kernel Mailing , =?UTF-8?B?RnLDqWTDqXJpYyBXZWlzYmVja2Vy?= , Kees Cook , Greg Kerr , Phil Auld , Valentin Schneider , Mel Gorman , Pawan Gupta , Paolo Bonzini Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > Thanks for the clarification. > > Yes, this is the initialization issue I mentioned before when core > scheduling is initially enabled. rq1's vruntime is bumped the first time > update_core_cfs_rq_min_vruntime() is called and if there are already > some tasks queued, new tasks queued on rq1 will be starved to some extent. > > Agree that this needs fix. But we shouldn't need do this afterwards. > > So do I understand correctly that patch1 is meant to solve the > initialization issue? I think we need this update logic even after initialization. I mean, core runqueue's min_vruntime can get updated every time when the core runqueue's min_vruntime changes with respect to the sibling's min_vruntime. So, whenever this update happens, we would need to propagate the changes down the tree right? Please let me know if I am visualizing it wrong. Thanks, Vineeth