Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932334AbVLFQ4l (ORCPT ); Tue, 6 Dec 2005 11:56:41 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932345AbVLFQ4l (ORCPT ); Tue, 6 Dec 2005 11:56:41 -0500 Received: from mx1.redhat.com ([66.187.233.31]:27525 "EHLO mx1.redhat.com") by vger.kernel.org with ESMTP id S932333AbVLFQ4k (ORCPT ); Tue, 6 Dec 2005 11:56:40 -0500 Date: Tue, 6 Dec 2005 11:56:07 -0500 From: Dave Jones To: Erik Mouw Cc: Lee Revell , Andi Kleen , Venkatesh Pallipadi , Andrew Morton , cpufreq , linux-kernel Subject: Re: [PATCH] CPU frequency display in /proc/cpuinfo Message-ID: <20051206165607.GA440@redhat.com> Mail-Followup-To: Dave Jones , Erik Mouw , Lee Revell , Andi Kleen , Venkatesh Pallipadi , Andrew Morton , cpufreq , linux-kernel References: <20051202181927.GD9766@wotan.suse.de> <20051202104320.A5234@unix-os.sc.intel.com> <20051204164335.GB32492@isilmar.linta.de> <20051204183239.GE14247@wotan.suse.de> <1133725767.19768.12.camel@mindpipe> <20051205011611.GA12664@redhat.com> <20051205130224.GC17993@harddisk-recovery.com> <20051205172513.GB12664@redhat.com> <20051206111349.GB32737@harddisk-recovery.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20051206111349.GB32737@harddisk-recovery.com> User-Agent: Mutt/1.4.2.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1274 Lines: 30 On Tue, Dec 06, 2005 at 12:13:49PM +0100, Erik Mouw wrote: > On Mon, Dec 05, 2005 at 12:25:13PM -0500, Dave Jones wrote: > > On Mon, Dec 05, 2005 at 02:02:24PM +0100, Erik Mouw wrote: > > > If you want a userspace governor to change the CPU speed, you need to > > > export the value to userland. > > > > We have sysfs files for that. > > Earlier in this thread you said (I should have quoted that, my fault): > > Adding any other interface to obtain this value is equally as broken. > > So I'm confused, sysfs one of the "any other interfaces"... userspace governors need to know the available frequencies to scale to, which they obtain from sysfs. In addition, we maintain an index as to which of those is currently chosen. However, programs should not rely on this to be a "how fast is my CPU" status, as it's totally meaningless. It's there purely for humans to see "Yes, X < Y, so I'm going at the lower of the frequencies my CPU can do", not for programs to calculate delays loops and such. Dave - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/