From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753556AbcAGV5r (ORCPT ); Thu, 7 Jan 2016 16:57:47 -0500 Received: from mga04.intel.com ([192.55.52.120]:47199 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752427AbcAGV5q (ORCPT ); Thu, 7 Jan 2016 16:57:46 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.20,534,1444719600"; d="scan'208";a="886003833" Date: Thu, 7 Jan 2016 13:57:45 -0800 From: Andi Kleen To: Stephane Eranian Cc: LKML , Arnaldo Carvalho de Melo , Jiri Olsa , Namhyung Kim , Peter Zijlstra , Ingo Molnar , Adrian Hunter Subject: Re: [RFC] perf record: missing buildid for callstack modules Message-ID: <20160107215745.GV25832@tassilo.jf.intel.com> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jan 07, 2016 at 01:56:14PM -0800, Stephane Eranian wrote: > Hi, > > Whenever you do: > > $ perf record -g -a sleep 10 > > Perf will collect the callstack for each sample. At the end of the > run, perf record > adds the buildid for all dso with at least one sample. But when it does this, it > only looks at the sampled IP and ignore the modules traversed by the callstack. > That means that, it is not possible to uniquely identify the modules executed, > unless they had at least one IP sample captured. But this is not > always the case. > > How about providing an option to perf record to force collecting > buildid for all IPs > captured in the callstack? I understand that would cost more at the end of the > collection, but this would be beneficial to several monitoring scenarios. If you do that I would rather collect buildid for everything that is synthesized (everything in /proc) -Andi