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 182B6EE8009 for ; Fri, 8 Sep 2023 14:11:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243709AbjIHOLN (ORCPT ); Fri, 8 Sep 2023 10:11:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44124 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233484AbjIHOLM (ORCPT ); Fri, 8 Sep 2023 10:11:12 -0400 Received: from mail-wr1-x42e.google.com (mail-wr1-x42e.google.com [IPv6:2a00:1450:4864:20::42e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5EEFF1BF1 for ; Fri, 8 Sep 2023 07:11:08 -0700 (PDT) Received: by mail-wr1-x42e.google.com with SMTP id ffacd0b85a97d-31c65820134so1925983f8f.1 for ; Fri, 08 Sep 2023 07:11:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=layalina-io.20230601.gappssmtp.com; s=20230601; t=1694182267; x=1694787067; darn=vger.kernel.org; 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=C0CQ0+G47TeLzn0nHNVztADMp6FUr773QDhjmSsmMsc=; b=jNq/RTxzPUJ9vWYc8A2KgC+QnDIl/IwQuDoA0yigFB0QDlvx1rW4JRX7mgaq/I5TiX sKdEDFhK5zh9CD2sMk95uKgsAMJ5NjF0ZaD/qYjpUwdBIxX4cyb0NO6VpVP36kQt74L1 bQJjmWg6fgb5z0WffyxpuS5bBH/2mAGZF7OKkkUpbt0nC2/2Kfndba3kfWw+To9y0Xjj 9UmquYLnRdTWqCzD5tmzZX1FT8dXU2SJs5ueBC46b+nu6xbSK8dk/UIqhpNuPm2hUCbj 1ep8qJ8aZ0sq87iWi2B1UCcdjmunJPaWVhoFjZ2x2rq8TpPydcsf+gLGAPoOBSVObRcj ++FQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1694182267; x=1694787067; 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=C0CQ0+G47TeLzn0nHNVztADMp6FUr773QDhjmSsmMsc=; b=XNtsdLHMiIRBKMHkBibr0jSiBM2UklO6idHdrTh1HkNRI0obuWFgdWhplff+DisT+Y wDHMWdqRvJOScVX+QcCuiOe7g6VadpDGNfliil0Ry2Y8U1hPKnt5OysN+VfnM6atc4J5 0IQnWlaxy4jfnh5/sFOmuTZdbNzjuQxd3rbQ5N47tvGbQP1b97adMqgZGH5B5DvBL7dM E97gzcuxyyLy6Urzau87c79udTTGhdbCGn2ANjD/ALYnrbAHLIrX3aNhMzv8rybDifMn QIsbyW3mPHpspA9DJuLe6LGwVnhERrkM1rm4dZOz/Db0Jptp5LXRmmTgjNvw2Ww2IMzp ibVA== X-Gm-Message-State: AOJu0YxGL089h62D+APFCoiJLD0G34uSlO/ZzBjQI9Skv+rMhOZ/5ps7 JfSTuH6j4kQgqFuFP1/nguyfUQ== X-Google-Smtp-Source: AGHT+IHaPpfGXwKUS+DavTXFA7zmXThPHAMTgMK1jjMsl6KSe5TFLr3UKuPqL8lYS+DukvL+zSfDvA== X-Received: by 2002:a5d:6142:0:b0:314:1f6:2c24 with SMTP id y2-20020a5d6142000000b0031401f62c24mr2170720wrt.36.1694182266828; Fri, 08 Sep 2023 07:11:06 -0700 (PDT) Received: from airbuntu (host109-151-228-137.range109-151.btcentralplus.com. [109.151.228.137]) by smtp.gmail.com with ESMTPSA id r15-20020a5d694f000000b003143c6e09ccsm2209653wrw.16.2023.09.08.07.11.05 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 08 Sep 2023 07:11:06 -0700 (PDT) Date: Fri, 8 Sep 2023 15:11:05 +0100 From: Qais Yousef To: Peter Zijlstra Cc: Ingo Molnar , "Rafael J. Wysocki" , Viresh Kumar , Vincent Guittot , Dietmar Eggemann , linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, Lukasz Luba Subject: Re: [RFC PATCH 0/7] sched: cpufreq: Remove magic margins Message-ID: <20230908141105.ofoht5z66sm6mmq2@airbuntu> References: <20230827233203.1315953-1-qyousef@layalina.io> <20230907130805.GE10955@noisy.programming.kicks-ass.net> <20230908001725.mtqbse3xwhzvo5qp@airbuntu> <20230908102511.GA24372@noisy.programming.kicks-ass.net> <20230908133336.uge4hcnx4cum3lg5@airbuntu> <20230908135939.GD24372@noisy.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20230908135939.GD24372@noisy.programming.kicks-ass.net> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/08/23 15:59, Peter Zijlstra wrote: > On Fri, Sep 08, 2023 at 02:33:36PM +0100, Qais Yousef wrote: > > > > (even hardware has these things today, we get 0-255 values that do > > > 'something' uarch specific) > > > > Ah, could I get some pointers please? > > Intel HWP.EPP and AMD CPPC EPP I think.. both intel-pstate and > amd-pstate have EPP thingies. Okay, thanks! So do you see tying this to the presence of some hardware mechanisms and provide a fallback for the other systems to define it somehow would be the best way to explore this? Cheers -- Qais Yousef