From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756063AbXJKFR0 (ORCPT ); Thu, 11 Oct 2007 01:17:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752946AbXJKFRS (ORCPT ); Thu, 11 Oct 2007 01:17:18 -0400 Received: from smtp2.linux-foundation.org ([207.189.120.14]:39514 "EHLO smtp2.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752878AbXJKFRR (ORCPT ); Thu, 11 Oct 2007 01:17:17 -0400 Date: Wed, 10 Oct 2007 22:17:04 -0700 From: Andrew Morton To: mgross@linux.intel.com Cc: arjan@infradead.org, linux-kernel@vger.kernel.org, torvalds@linux-foundation.org, linux-pm@lists.linux-foundation.org, mark.gross@intel.com Subject: Re: pm qos infrastructure and interface Message-Id: <20071010221704.6e438c71.akpm@linux-foundation.org> In-Reply-To: <20071004215139.GA20078@linux.intel.com> References: <20071004215139.GA20078@linux.intel.com> X-Mailer: Sylpheed 2.4.1 (GTK+ 2.8.17; x86_64-unknown-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 4 Oct 2007 14:51:39 -0700 Mark Gross wrote: > The following patch is a generalization of the latency.c implementation > done by Arjan last year. It provides infrastructure for more than one > parameter, and exposes a user mode interface for processes to register > pm_qos expectations of processes. > > > This interface provides a kernel and user mode interface for registering > performance expectations by drivers, subsystems and user space > applications on one of the parameters. > > Currently we have {cpu_dma_latency, network_latency, network_throughput} > as the initial set of pm_qos parameters. > > The infrastructure exposes multiple misc device nodes one per > implemented parameter. The set of parameters implement is defined by > pm_qos_power_init() and pm_qos_params.h. This is done because having > the available parameters being runtime configurable or changeable from a > driver was seen as too easy to abuse. I'm a bit surprised that this change appears to have no configurability. If one has set CONFIG_PM=n (for example), shouldn't it all go away?