From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.fusionio.com ([64.244.102.31]:38224 "EHLO mx2.fusionio.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753053Ab0HLLuO (ORCPT ); Thu, 12 Aug 2010 07:50:14 -0400 Message-ID: <4C63DFE6.9000608@fusionio.com> Date: Thu, 12 Aug 2010 07:49:58 -0400 From: Jens Axboe MIME-Version: 1.0 Subject: Re: Build issue on arm: undefined reference to `get_cpu_clock' References: <4C6141EC.7060205@free-electrons.com> <4C6194C8.2090405@fusionio.com> <4C63B92F.3000009@free-electrons.com> In-Reply-To: <4C63B92F.3000009@free-electrons.com> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Sender: fio-owner@vger.kernel.org List-Id: fio@vger.kernel.org To: Michael Opdenacker Cc: fio mailing list On 08/12/2010 05:04 AM, Michael Opdenacker wrote: > Hi Jens, > > On 08/10/2010 08:04 PM, Jens Axboe wrote: >> On 08/10/2010 08:11 AM, Michael Opdenacker wrote: >>> The get_cpu_clock function is only defined in >>> arch/arch-ia64.h >>> arch/arch-x86.h >>> arch/arch-x86_64.h >>> >>> How are other architectures supported? I don't understand fio can >>> support them without defining the get_cpu_clock() function. >>> >>> I did my tests on version 1.42, but faced the same issues with the >>> latest git version. >>> >> Indeed, dunno what happened there. I'll take a look. >> > I have seen your addition of get_cpu_clock() for the ppc architecture. > > By the way, wouldn't it be more portable to use the POSIX > clock_gettime() function instead of reading an architecture dependent > register? At least, this is recommended on > http://en.wikipedia.org/wiki/Time_Stamp_Counter Of course using clock_gettime() would be more portable. The point of the CPU clock is speed. If you are testing IOPS into the ranges of millions and doing ~5 clock calls per IO, then portability takes a back seat to speed. But arm needs to work of course, I will commit a patch to fix it as soon as I can. -- Jens Axboe Confidentiality Notice: This e-mail message, its contents and any attachments to it are confidential to the intended recipient, and may contain information that is privileged and/or exempt from disclosure under applicable law. If you are not the intended recipient, please immediately notify the sender and destroy the original e-mail message and any attachments (and any copies that may have been made) from your system or otherwise. Any unauthorized use, copying, disclosure or distribution of this information is strictly prohibited.