Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751462AbXBCUDK (ORCPT ); Sat, 3 Feb 2007 15:03:10 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751464AbXBCUDK (ORCPT ); Sat, 3 Feb 2007 15:03:10 -0500 Received: from e36.co.us.ibm.com ([32.97.110.154]:41896 "EHLO e36.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751462AbXBCUDJ (ORCPT ); Sat, 3 Feb 2007 15:03:09 -0500 Message-ID: <45C4EA7D.4000709@us.ibm.com> Date: Sat, 03 Feb 2007 14:03:09 -0600 From: Maynard Johnson User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.3) Gecko/20040910 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Arnd Bergmann CC: cbe-oss-dev@ozlabs.org, linuxppc-dev@ozlabs.org, oprofile-list@lists.sourceforge.net, linux-kernel@vger.kernel.org Subject: Re: [Cbe-oss-dev] [RFC, PATCH 4/4] Add support to OProfile for profiling Cell BE SPUs -- update References: <45BE4ED0.5030808@us.ibm.com> <200701310752.48632.arnd@arndb.de> <45C36B21.60400@us.ibm.com> <200702030840.06270.arnd@arndb.de> In-Reply-To: <200702030840.06270.arnd@arndb.de> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1417 Lines: 42 Arnd Bergmann wrote: >On Friday 02 February 2007 17:47, Maynard Johnson wrote: > > >>>We also want to be able to profile the context switch code itself, which >>>means that we also need one event buffer associated with the kernel to >>>collect events that for a zero context_id. >>> >>> >>The hardware design precludes tracing both SPU and PPU simultaneously. >> >> >> >I mean the SPU-side part of the context switch code, which you can find >in arch/powerpc/platforms/cell/spufs/spu_{save,restore}*. > >This code is the one that runs when context_id == 0 is passed to the >callback. > > I presume you mean 'object_id'. What you're asking for is a new requirement, and one which I don't believe is achievable in the current timeframe. Since this is spufs code that's dynamicaly loaded into the SPU at runtime, the symbol information for this code is not accessible to the userspace post-processing tools. It would require an altogether different mechanism to record samples along with necessary information, not to mention the changes required in the post-processing tools. This will have to be a future enhancement. -Maynard > Arnd <>< > > - 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/