Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759980Ab3GaOH4 (ORCPT ); Wed, 31 Jul 2013 10:07:56 -0400 Received: from mail-ve0-f176.google.com ([209.85.128.176]:46421 "EHLO mail-ve0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759802Ab3GaOHz (ORCPT ); Wed, 31 Jul 2013 10:07:55 -0400 Date: Wed, 31 Jul 2013 11:07:46 -0300 From: Arnaldo Carvalho de Melo To: Namhyung Kim Cc: Namhyung Kim , Peter Zijlstra , Paul Mackerras , Ingo Molnar , LKML , Steven Rostedt , Frederic Weisbecker , Jiri Olsa , David Ahern , Stephane Eranian , Jeremy Eder Subject: Re: [PATCH 01/17] perf util: Save pid-cmdline mapping into tracing header Message-ID: <20130731140746.GA3614@ghostprotocols.net> References: <1375175954-798-1-git-send-email-namhyung@kernel.org> <1375175954-798-2-git-send-email-namhyung@kernel.org> <20130730132839.GA2607@ghostprotocols.net> <51F85FAA.2090400@lge.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <51F85FAA.2090400@lge.com> X-Url: http://acmel.wordpress.com User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1197 Lines: 26 Em Wed, Jul 31, 2013 at 09:51:54AM +0900, Namhyung Kim escreveu: > 2013-07-30 오후 10:28, Arnaldo Carvalho de Melo 쓴 글: > >Em Tue, Jul 30, 2013 at 06:18:58PM +0900, Namhyung Kim escreveu: > >>Current trace info data lacks the saved cmdline mapping which is > >>needed for pevent to find out the comm of a task. Add this and bump > >>up the version number so that perf can determine its presence when > >>reading. > >Can't we get this from the PERF_RECORD_COMM synthesized at the beginning > >of the session + the kernel generated ones for new threads? > >We would just call machine__find_thread() and use thread->comm, etc, no? > Yes, I think it's doable. However it needs an additional perf event > only to generate the COMM events. So I decided not to do it and I don't think this is a problem, its in line with Ingo's suggestion of a new perf ioctl to ask the kernel to generate PERF_RECORD_MMAP events for existing threads. - Arnaldo -- 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/