Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756717AbXLMCIp (ORCPT ); Wed, 12 Dec 2007 21:08:45 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751229AbXLMCIg (ORCPT ); Wed, 12 Dec 2007 21:08:36 -0500 Received: from terminus.zytor.com ([198.137.202.10]:53462 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751096AbXLMCIg (ORCPT ); Wed, 12 Dec 2007 21:08:36 -0500 Message-ID: <476093B6.7080306@zytor.com> Date: Wed, 12 Dec 2007 18:06:46 -0800 From: "H. Peter Anvin" User-Agent: Thunderbird 2.0.0.9 (X11/20071115) MIME-Version: 1.0 To: Jan Engelhardt CC: Rene Herman , Linux Kernel , dpreed@reed.com, Alan Cox , pavel@ucw.cz, andi@firstfloor.org, rol@as2917.net, Krzysztof Halasa , david@davidnewall.com, john@stoffel.org, linux-os@analogic.com Subject: Re: [RFT] Port 0x80 I/O speed References: <475F1DC6.5090403@keyaccess.nl> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1259 Lines: 28 Jan Engelhardt wrote: > On Dec 12 2007 00:31, Rene Herman wrote: >> Would some people on x86 (both 32 and 64) be kind enough to compile and run the >> attached program? This is about testing how long I/O port access to port 0x80 >> takes. It measures in CPU cycles so CPU speed is crucial in reporting. >> > > Transmeta TM5800 CPU with nominal frequency 933 MHz, but it has a > hardware(!) 'ondemand' governor over the range of frequencies that > the user allowed scaling over, irrespective of the software governor. > (That is, if the CPU can do 300,533 and 933 MHz, and setting the > min/max to 300/533 will cause the hardware to 'ondemand' between 300 > and 533 only. And that even if 'performance' is set on the software > side - so the only way to enforce 'performance' is to actually set > min=933.) > Actually it has two different ones (economy and performance), you can use the "longrun" utility to select which one. Either way, all Transmeta processors have a fixed TSC, so there is no issue. -hpa -- 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/