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=-5.8 required=3.0 tests=BAYES_00,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 5C1D8C11F64 for ; Mon, 28 Jun 2021 20:10:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 43A766197D for ; Mon, 28 Jun 2021 20:10:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234906AbhF1UM5 (ORCPT ); Mon, 28 Jun 2021 16:12:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56426 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237318AbhF1UMr (ORCPT ); Mon, 28 Jun 2021 16:12:47 -0400 Received: from mail-lf1-x12b.google.com (mail-lf1-x12b.google.com [IPv6:2a00:1450:4864:20::12b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2FC0EC061760 for ; Mon, 28 Jun 2021 13:10:21 -0700 (PDT) Received: by mail-lf1-x12b.google.com with SMTP id h15so34771263lfv.12 for ; Mon, 28 Jun 2021 13:10:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=aKntq9zj9C3lmXbOlECBxOpuMyE7fATYtBVOgQbgdBw=; b=STHIGwaKO4TwPixEhHTCX3RUjRHVcFp6ftt12txqWTVJ8qIhuUdHzV/Hgz3GVzetHF 13P9xwrLj9IPlbcEeB6ahEGie62LKL/rU4uwBFj2e5WHkP23+KEKRNhzJp2ZBNNwl8ge OolxXmvTQzV24bdGbLNxX5RnZivB0duHGOxoc= 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=aKntq9zj9C3lmXbOlECBxOpuMyE7fATYtBVOgQbgdBw=; b=T18o29q4kDlKnVY9XXOgVwGLuZGbVVXfaDOoZJSw7ybceS2CQSKrl2cBD36Eee2Aop 4LV2FwhvWf6Pd5Pf7bBwORIpUKGdzLMVSvk4sTlyZs33kjhiOmu4A4lso3o5SjteyjBR RmkLEmcaSARf/kV3cUd2qvcUK+3yGuL9FrV9f+q4WkgPGFq8Ffk64ztRwBv28tOyE5HN mjC/t07Em0/ZMKRmZwc8qUN3IYnYv6wF2Lz6XZZgted+ZuYgR47JyGEu6m4+QtFcqhk+ 6Pu6ceKWo40puj0pjDBE8bEkbhxkIYZ1IxiBeMHeofTUywgXVdvfCH5QKKJU1t9xGQq8 ugYg== X-Gm-Message-State: AOAM5305oZMCTEwbCvHbXNe9Ci2lKE5ucYxZhtSstXa7x2uUubT4WsCA Du/Y4NnSEMU2d4TwCPBw+HPX07G6LqP8CfZz X-Google-Smtp-Source: ABdhPJwTgyqxjkIzO3omp+uvomDvEJ9rHMaQlfgebi/gIYlUq69fvHNttzIPSuBrFxMKTghpyZrm5Q== X-Received: by 2002:a19:7d8b:: with SMTP id y133mr20767155lfc.284.1624911019051; Mon, 28 Jun 2021 13:10:19 -0700 (PDT) Received: from mail-lj1-f179.google.com (mail-lj1-f179.google.com. [209.85.208.179]) by smtp.gmail.com with ESMTPSA id y24sm1650727ljj.16.2021.06.28.13.10.18 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 28 Jun 2021 13:10:18 -0700 (PDT) Received: by mail-lj1-f179.google.com with SMTP id k21so6770871ljh.2 for ; Mon, 28 Jun 2021 13:10:18 -0700 (PDT) X-Received: by 2002:a05:651c:32e:: with SMTP id b14mr850972ljp.251.1624911018010; Mon, 28 Jun 2021 13:10:18 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Linus Torvalds Date: Mon, 28 Jun 2021 13:10:02 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH] sched/core: Disable CONFIG_SCHED_CORE by default To: Ingo Molnar Cc: Linux Kernel Mailing List , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Mel Gorman , Daniel Bristot de Oliveira , Thomas Gleixner , Andrew Morton Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jun 28, 2021 at 12:57 PM Ingo Molnar wrote: > > You are completely right, I missed this. Find below the patch to fix it - I think you should update the helptext too, which currently says that it's enabled if SCHED_SMT is enabled. And yes, it may be that there is no measurable performance downside, but this feature has been discussed and under development for a long time now, and I'd like the default to try to limit the impact since it makes little sense to most people. Linus