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 D1162C10F14 for ; Thu, 10 Oct 2019 14:30:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A980A206B6 for ; Thu, 10 Oct 2019 14:30:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=digitalocean.com header.i=@digitalocean.com header.b="Z2Y6iMRO" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726462AbfJJOaB (ORCPT ); Thu, 10 Oct 2019 10:30:01 -0400 Received: from mail-oi1-f196.google.com ([209.85.167.196]:44978 "EHLO mail-oi1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726070AbfJJOaB (ORCPT ); Thu, 10 Oct 2019 10:30:01 -0400 Received: by mail-oi1-f196.google.com with SMTP id w6so5036735oie.11 for ; Thu, 10 Oct 2019 07:30:00 -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=FJ4xsQtnmbNbtQPuMzUcS/Crf0fRiybq/RQZW0N2ou4=; b=Z2Y6iMROzX1lFH94Pe5S/VUAV16TG4jco5oEnqJqk6ymR4R3d32XPsE8IGJncDXfAy gcIPiwJ4NeNBsuA0RuYwIw4fxgqBevVYm/SCbQqQHfkoiT7UHtxiBTOCIuofzFrS0ZJ4 Ztsq1PNOZTfkDZpW+HSbO52LFwBaMFN8NoXPU= 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=FJ4xsQtnmbNbtQPuMzUcS/Crf0fRiybq/RQZW0N2ou4=; b=pGnoZ8p0cF2BiGD+3nkpdPNPTOG6j58jiuQvZfOfWcyVtFt9CGZK69A6b/8fVM3/jy sgs1tUdHOvInJNg6rdGQjISfbPMAH/4LuNjL3gky1a3NraXYUttzYS4EpYzCF1smZUrP tFx/2Ax5ii6GFXzCgYY/Put8AcDAziOXx2RBdevkcxpxunlHf8x9+7zoTQ+ufSpZbw3U 9u1cly6yMLewAJFKoN4MCfBBebSUhyMoEbYMhqQlXb0pQzyOWc9nfzn8hdmU8dQiDabB qi34lUy9tCRvYR3prDUCm37gQJsAo08aJv6d7SQcuohU4FNptsx5R0vIktG6FriqBh6K 4d/A== X-Gm-Message-State: APjAAAWq/XO3CSBlxRH5V8HJyUcv89xbiYxk8JiTdc32AxbMB4zWwajI ir1qujLEZwdowg7Zn6Eug2JrC+WJgh/kl7RzAWXHPg== X-Google-Smtp-Source: APXvYqwpTdrni78lzedCnFmfEtgKVKZKULWgJi//ul6gHs9Z5OzR3dtKZlNfwCRPZls8pQipDQeUIlEmgRm50zXCdIs= X-Received: by 2002:aca:5f0a:: with SMTP id t10mr8016452oib.20.1570717800194; Thu, 10 Oct 2019 07:30:00 -0700 (PDT) MIME-Version: 1.0 References: <20190802153715.GA18075@sinkpad> <69cd9bca-da28-1d35-3913-1efefe0c1c22@linux.intel.com> <20190911140204.GA52872@aaronlu> <7b001860-05b4-4308-df0e-8b60037b8000@linux.intel.com> <20190912123532.GB16200@aaronlu> <20191010135436.GA67897@aaronlu> In-Reply-To: <20191010135436.GA67897@aaronlu> From: Vineeth Remanan Pillai Date: Thu, 10 Oct 2019 10:29:47 -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 > I didn't see why we need do this. > > We only need to have the root level sched entities' vruntime become core > wide since we will compare vruntime for them across hyperthreads. For > sched entities on sub cfs_rqs, we never(at least, not now) compare their > vruntime outside their cfs_rqs. > The reason we need to do this is because, new tasks that gets created will have a vruntime based on the new min_vruntime and old tasks will have it based on the old min_vruntime and it can cause starvation based on how you set the min_vruntime. With this new patch, we normalize the whole tree so that new tasks and old tasks compare with the same min_vruntime. Thanks, Vineeth