Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265959AbUAKT2d (ORCPT ); Sun, 11 Jan 2004 14:28:33 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265961AbUAKT2d (ORCPT ); Sun, 11 Jan 2004 14:28:33 -0500 Received: from dotnetslash.net ([66.199.224.19]:32006 "EHLO mail.dotnetslash.net") by vger.kernel.org with ESMTP id S265959AbUAKT2a (ORCPT ); Sun, 11 Jan 2004 14:28:30 -0500 Date: Sun, 11 Jan 2004 14:28:29 -0500 From: "Mark W. Alexander" To: Linux Kernel Mailing List Subject: 2.6.0->2.6.1 /proc/cpuinfo behavior change Message-ID: <20040111192829.GA27147@dotnetslash.net> Mail-Followup-To: Linux Kernel Mailing List Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.3.28i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3293 Lines: 115 I'm not currently subscribed. Please cc: me on responses. The behavior of /proc/cpuinfo on cpu frequency scaling has changed between 2.6.0 and 2.6.1(-mm2). On 2.6.0, /proc/cpuinfo reports the cpu MHz as set by scaling_setspeed, with bogo-mips numbers along traditional values. On 2.6.1-mm2, /proc/cpuinfo _always_ reports cpu MHz == cpuinfo_max_freq, with bogo-mips values closer to the setting of scaling_setspeed. In both cases, /proc/stat information appears appropriate to the actual speed. (At least, AFAICT, that's where gKrellm get's it's info and it seems to report correctly.) I didn't glean anything from the changelogs that explains this behavior. Is it a bug or a feature? Example output: ########################### 2.6.0 ###################### bash-2.05b# uname -r 2.6.0-ze4400-3 bash-2.05b# echo 1800000 >/sys/devices/system/cpu/cpu0/cpufreq/scaling_setspeed bash-2.05b# cat /proc/cpuinfo processor : 0 vendor_id : AuthenticAMD cpu family : 6 model : 8 model name : mobile AMD Athlon(tm) XP2200+ stepping : 1 cpu MHz : 1788.655 cache size : 256 KB fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 1 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 sep mtrr pge mca cmov pat pse36 mmx fxsr sse syscall mp mmxext 3dnowext 3dnow bogomips : 3538.94 bash-2.05b# echo 532000 >/sys/devices/system/cpu/cpu0/cpufreq/scaling_setspeed bash-2.05b# cat /proc/cpuinfo processor : 0 vendor_id : AuthenticAMD cpu family : 6 model : 8 model name : mobile AMD Athlon(tm) XP2200+ stepping : 1 cpu MHz : 529.971 cache size : 256 KB fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 1 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 sep mtrr pge mca cmov pat pse36 mmx fxsr sse syscall mp mmxext 3dnowext 3dnow bogomips : 1048.57 ########################### 2.6.1-mm2 ###################### bash-2.05b# uname -r 2.6.1-mm2-ze4400-1 bash-2.05b# echo 1800000 >/sys/devices/system/cpu/cpu0/cpufreq/scaling_setspeed bash-2.05b# cat /proc/cpuinfo processor : 0 vendor_id : AuthenticAMD cpu family : 6 model : 8 model name : mobile AMD Athlon(tm) XP2200+ stepping : 1 cpu MHz : 1789.000 cache size : 256 KB fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 1 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 sep mtrr pge mca cmov pat pse36 mmx fxsr sse syscall mp mmxext 3dnowext 3dnow bogomips : 1777.66 bash-2.05b# echo 532000 >/sys/devices/system/cpu/cpu0/cpufreq/scaling_setspeed bash-2.05b# cat /proc/cpuinfo processor : 0 vendor_id : AuthenticAMD cpu family : 6 model : 8 model name : mobile AMD Athlon(tm) XP2200+ stepping : 1 cpu MHz : 1789.000 cache size : 256 KB fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 1 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 sep mtrr pge mca cmov pat pse36 mmx fxsr sse syscall mp mmxext 3dnowext 3dnow bogomips : 526.71 -- Mark W. Alexander slash@dotnetslash.net - 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/