From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753576Ab0CDC7m (ORCPT ); Wed, 3 Mar 2010 21:59:42 -0500 Received: from mx3.mail.elte.hu ([157.181.1.138]:41386 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753206Ab0CDC7i (ORCPT ); Wed, 3 Mar 2010 21:59:38 -0500 Date: Thu, 4 Mar 2010 03:59:08 +0100 From: Ingo Molnar To: David Miller , Arnaldo Carvalho de Melo Cc: eranian@google.com, peterz@infradead.org, linux-kernel@vger.kernel.org, paulus@samba.org, robert.richter@amd.com, fweisbec@gmail.com Subject: Re: [RFC][PATCH 07/11] perf: Provide PERF_SAMPLE_REGS Message-ID: <20100304025908.GC23633@elte.hu> References: <1267637995.25158.96.camel@laptop> <20100303.095553.105186917.davem@davemloft.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100303.095553.105186917.davem@davemloft.net> User-Agent: Mutt/1.5.20 (2009-08-17) X-ELTE-SpamScore: -2.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.0 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.5 -2.0 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * David Miller wrote: > And more generally aren't we supposed to be able to eventually analyze perf > dumps on any platform not just the one 'perf' was built under? A aidenote: in this cycle Arnaldo improved this aspect of perf (and those changes are now upstream). In theory you should be able to do a 'perf record' + 'perf archive' on your Sparc box and then analyze it via 'perf report' on an x86 box - and vice versa. ( Note, it was not tested in that specific combination - another combination was tested by Arnaldo: 32-bit PA-RISC profile interpreted on 64-bit x86. ) So yes, i agree that at minimum perf should be able to tell apart the nature of any recording and flag combinations it cannot handle (yet). Btw, i think the most popular use of PEBS is its precise nature, not the register dumping aspect per se. If the kernel can provide that transparently then that's a usecase that does not need a register dump (in user-space that is). It's borderline doable on x86 ... Thanks, Ingo