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=-5.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 D57B0C43612 for ; Fri, 11 Jan 2019 09:47:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A554A2177B for ; Fri, 11 Jan 2019 09:47:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1547200071; bh=joi+/qu2KggeRT2QhMBkDtuLD1QQgr/tYr51hq8fGfE=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=FjzOP0DP2WHBVVeJ6GUDy7/HrdNpejE6szBqiOxDhcvdAM37sNuhs6boqkAQX9aRc JffOScSlSkP+F3ptYK4tsikILC9tco/r2je6bp9a+ipJMddugnsy9/tS7o0uvEiI6e HG+ZnGFS/zzkfNmIIiC17qacONaO2YTdINPjv6Ds= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731383AbfAKJru (ORCPT ); Fri, 11 Jan 2019 04:47:50 -0500 Received: from mail-oi1-f195.google.com ([209.85.167.195]:37668 "EHLO mail-oi1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727653AbfAKJrt (ORCPT ); Fri, 11 Jan 2019 04:47:49 -0500 Received: by mail-oi1-f195.google.com with SMTP id y23so11737187oia.4; Fri, 11 Jan 2019 01:47:49 -0800 (PST) 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=joi+/qu2KggeRT2QhMBkDtuLD1QQgr/tYr51hq8fGfE=; b=GLBhcnFFe39duuF2YhAqtzJgFWDboyEiLLDEzzpdsmSzP7t2oUaSTNtwHxGl1kpfOz +dp7HCM9yYSFWVISg7v/qsBn8pe7apPU/FAAR9qVKFxm4uEavQOAnVGhCeTU0lDianfO 7QSEdyuoNSgPVPaResf/GcNldAPnRb6WXekAL0S+VByD0snLwvx0vo2sWSj7XSixOOIm b2qZ9qga9wtNZH64FaJJxMy1etM02Oghnrnj8Ll7N4cBKamqYeAul2dMrQsE5vVcL+9o 2Gl4BMpg3zadUxggUp7DZ4etK66rZE8GHefYbEr2u4Q6Pw6FNRc9ebZGQGapmlebrs5S LFOQ== X-Gm-Message-State: AJcUukdU8cX8Om84NMbQsJXL0jtUvXAOzIzCazJ1AeAnL9y9AQzr13WZ l2tZySwwnweM00m9SdR/ySFH7r7Ia7V3kPfbshM= X-Google-Smtp-Source: ALg8bN4BRPTdyyzB3EOX3fxzFFHv17XhCduNRZAsjxehc8MqWrNTj+YbEtO6eJCUMWos+V0ptv1W+o0H0jipLk0yQek= X-Received: by 2002:aca:3d42:: with SMTP id k63mr9078666oia.95.1547200068692; Fri, 11 Jan 2019 01:47:48 -0800 (PST) MIME-Version: 1.0 References: In-Reply-To: From: "Rafael J. Wysocki" Date: Fri, 11 Jan 2019 10:47:37 +0100 Message-ID: Subject: Re: [PATCH 0/3] drivers: Frequency constraint infrastructure To: Viresh Kumar Cc: Rafael Wysocki , Greg Kroah-Hartman , "Rafael J. Wysocki" , Viresh Kumar , Linux PM , Vincent Guittot , Matthias Kaehlcke , Linux Kernel Mailing List 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 On Fri, Jan 11, 2019 at 10:18 AM Viresh Kumar wrote: > > Hi, > > This commit introduces the frequency constraint infrastructure, which > provides a generic interface for parts of the kernel to constraint the > working frequency range of a device. > > The primary users of this are the cpufreq and devfreq frameworks. The > cpufreq framework already implements such constraints with help of > notifier chains (for thermal and other constraints) and some local code > (for user-space constraints). The devfreq framework developers have also > shown interest [1] in such a framework, which may use it at a later > point of time. > > The idea here is to provide a generic interface and get rid of the > notifier based mechanism. > > Only one constraint is added for now for the cpufreq framework and the > rest will follow after this stuff is merged. > > Matthias Kaehlcke was involved in the preparation of the first draft of > this work and so I have added him as Co-author to the first patch. > Thanks Matthias. > > FWIW, This doesn't have anything to do with the boot-constraints > framework [2] I was trying to upstream earlier :) This is quite a bit of code to review, so it will take some time. One immediate observation is that it seems to do quite a bit of what is done in the PM QoS framework, so maybe there is an opportunity for some consolidation in there. Cheers, Rafael