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=-8.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL 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 D771DCA90AF for ; Wed, 13 May 2020 09:41:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B232E2078C for ; Wed, 13 May 2020 09:41:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="nbtBTs6X" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726891AbgEMJlY (ORCPT ); Wed, 13 May 2020 05:41:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47922 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726645AbgEMJlX (ORCPT ); Wed, 13 May 2020 05:41:23 -0400 Received: from mail-wm1-x343.google.com (mail-wm1-x343.google.com [IPv6:2a00:1450:4864:20::343]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8820CC061A0C for ; Wed, 13 May 2020 02:41:23 -0700 (PDT) Received: by mail-wm1-x343.google.com with SMTP id f134so13650832wmf.1 for ; Wed, 13 May 2020 02:41:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=NJBGaruknTCLtKKJk9/NPgVcIhnHRN5HOgLiTidMfps=; b=nbtBTs6Xx54r3xi5mFEcv4se2zQfkJy0cQh1tbJCIw8IoMzRCEr0oal1hCN8wgjJwG XJfDbD6yCAuuqlDeI7Ry1xErq+ap5T/xl3ude7Kf8KxrPAOkKt0I7tT+gue0xmLf03UW T7e5+LBwZVFtpdt1QkXQGwAyCQ8X7HkI6BligttJ82dncMKxLO6r9/fNTKcYJySDfwIR cRgHstp7X6H5NMznogdlwx1FUvoY9Ns4+KsmIXMTxizqrvkKIOMTkvUTVZDFaCJS2IkP yWiL85KWNcfvxM1s/c5bZSWwd3Y9ECI1Dc8APHKOiNg4ZliFiPwgPuftVHjIxUzlFmWi npSA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=NJBGaruknTCLtKKJk9/NPgVcIhnHRN5HOgLiTidMfps=; b=k2DXWDcz+GCn/FZCqO/tvj+/3Rnz1W50IxagSyRDpTymdT+DumB7/VUL2oGZGKgOJS Meg+oLg86Et7AyzYtdBAR5vJEt3vITKJjGWipuoyzK1bpP2r6M+11Febs/klSGNYodfV KKTFhounAiVZF6XOK17cGbVLvFFT+LPSuaVRCUaG1rDHy0U3qFi0TuRpjOJWJYH0aBKe 6uE0oPuCo8CAlpI3sAR265KSk7GKtUdQb5MVEFRb8n8lsZofGN5h+iGhMJ0+C5Iejp9I q8xEq68H7AJ8jlyj7QPJgBCXFE1ZbXZUipwwcRxCPUd5QQ+MlIpqfAxJAWGudM5gUGTP lPng== X-Gm-Message-State: AOAM530uuXm/UmOwtkBS/I5XS3oQhRYRmsbSqsG002efaLog/HcGslvQ 7u84sC3zjadmPaTN4VyV6E/X7g== X-Google-Smtp-Source: ABdhPJxIzSvxktEk0dfkDZAgXrtWIO1vC88KrHWFh9dWQyFJ4zAsOGcxznMe+hx/MAUnWP+KEEw9nQ== X-Received: by 2002:a1c:6245:: with SMTP id w66mr7104946wmb.33.1589362881903; Wed, 13 May 2020 02:41:21 -0700 (PDT) Received: from google.com ([2a00:79e0:d:110:d6cc:2030:37c1:9964]) by smtp.gmail.com with ESMTPSA id x24sm28184249wrd.51.2020.05.13.02.41.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 13 May 2020 02:41:20 -0700 (PDT) Date: Wed, 13 May 2020 10:41:17 +0100 From: Quentin Perret To: "Rafael J. Wysocki" Cc: Peter Zijlstra , Greg KH , Linux Kernel Mailing List , Linux PM , Thomas Gleixner , Ingo Molnar , Borislav Petkov , the arch/x86 maintainers , "H. Peter Anvin" , Sudeep Holla , Viresh Kumar , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Benjamin Segall , Mel Gorman , "Luis R. Rodriguez" , Kees Cook , Iurii Zaikin , Frederic Weisbecker , Todd Kjos , "Cc: Android Kernel" Subject: Re: [PATCH 00/14] Modularize schedutil Message-ID: <20200513094117.GB225140@google.com> References: <20200511090049.GA229633@google.com> <20200512092102.GA16151@google.com> <20200512135813.GA101124@google.com> <20200512151120.GB101124@google.com> <20200512162630.GC101124@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org Hi Rafael, On Tuesday 12 May 2020 at 19:30:52 (+0200), Rafael J. Wysocki wrote: > I don't see any technical reason for making schedutil modular in the > context of GKI other than to make the GKI image smaller, but I don't > expect that to be significant enough. The fact that we can make the image smaller, and we give vendors one less reason to not-want GKI _is_ desirable IMO. $ size vmlinux.* text data bss dec hex filename 19225963 9601976 491084 29319023 1bf5f6f vmlinux.after 19230599 9603236 491084 29324919 1bf7677 vmlinux.before ^ that's with the series applied. 'before' means sugov is =y, and 'after' is sugov =m. So modularizing saves just over 4K on text, and a bit of data too. Is it significant? Maybe not. But it's quite likely that those who don't use schedutil will find any unnecessary byte to be one too many. I just checked the size of modules in the default arm64 defconfig, and the median is ~4K of text. The average is a little bigger, but mostly because of a small number of really large modules (nouveau being the prime the example). So all in all, the sugov module is not particularly small by comparison with other things that have been modularized. A lot of small things can lead to significant savings at the end. Thanks, Quentin