From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S269375AbUHZTIt (ORCPT ); Thu, 26 Aug 2004 15:08:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S269376AbUHZTED (ORCPT ); Thu, 26 Aug 2004 15:04:03 -0400 Received: from mail.tmr.com ([216.238.38.203]:15113 "EHLO gatekeeper.tmr.com") by vger.kernel.org with ESMTP id S269391AbUHZS7Z (ORCPT ); Thu, 26 Aug 2004 14:59:25 -0400 To: linux-kernel@vger.kernel.org Path: not-for-mail From: Bill Davidsen Newsgroups: mail.linux-kernel Subject: Re: bizarre 2.6.8.1 /sys permissions Date: Thu, 26 Aug 2004 15:00:01 -0400 Organization: TMR Associates, Inc Message-ID: References: <20040826004857.GA5583@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Trace: gatekeeper.tmr.com 1093546378 9986 192.168.12.100 (26 Aug 2004 18:52:58 GMT) X-Complaints-To: abuse@tmr.com User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.2) Gecko/20040803 X-Accept-Language: en-us, en In-Reply-To: <20040826004857.GA5583@redhat.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Dave Jones wrote: > On Wed, Aug 25, 2004 at 04:31:50PM -0700, Dan Hollis wrote: > > > > $ cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_cur_freq > > > > cat: /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_cur_freq: Permission denied > > > Reading this file causes reads from hardware on some cpufreq drivers. > > > This can be a slow operation, so a user could degrade system performance > > > for everyone else by repeatedly cat'ing it. > > > > any reason why cpuinfo_cur_freq cant read cpu_khz ? > > cpufreq_cur_freq will be one of scaling_available_frequencies. > These are usually a value such as 1300MHz, where cpu_mhz is a > 'measured' value and will look something like 1303.852 > > the values cpufreq uses are the values either returned by the > hardware as its settable states, or from BIOS tables defining > those states. > > > or rather, is there any reason why cpuinfo_cur_freq and /proc/cpuinfo > > should legitimately differ? > > They aren't identical, and serve different purposes. Okay, so cpufreq just gives informational values in a table while /proc/cpuinfo actually reflects the speed of the CPU. Right? That's good, I thought there was an problem if they were different. -- -bill davidsen (davidsen@tmr.com) "The secret to procrastination is to put things off until the last possible moment - but no longer" -me