From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1753560AbcAGXrx (ORCPT <rfc822;w@1wt.eu>);
	Thu, 7 Jan 2016 18:47:53 -0500
Received: from mail.kernel.org ([198.145.29.136]:33377 "EHLO mail.kernel.org"
	rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
	id S1752634AbcAGXrw (ORCPT <rfc822;linux-kernel@vger.kernel.org>);
	Thu, 7 Jan 2016 18:47:52 -0500
Date: Thu, 7 Jan 2016 20:47:46 -0300
From: Arnaldo Carvalho de Melo <acme@kernel.org>
To: Namhyung Kim <namhyung@gmail.com>
Cc: Stephane Eranian <eranian@google.com>, LKML <linux-kernel@vger.kernel.org>,
        Jiri Olsa <jolsa@kernel.org>, Namhyung Kim <namhyung@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@kernel.org>,
        Adrian Hunter <adrian.hunter@intel.com>,
        "ak@linux.intel.com" <ak@linux.intel.com>
Subject: Re: [RFC] perf record: missing buildid for callstack modules
Message-ID: <20160107234746.GB19314@kernel.org>
References: <CABPqkBT3SV1qGuxLaA_Myz4wbs+KWJ3kLnqyhkTcpjism40JQw@mail.gmail.com>
 <20160107215945.GA19314@kernel.org>
 <CABPqkBRqkwj02jZHoQxpxOH7FjYTjAa_mLdZWvSWfv1-oqsuPQ@mail.gmail.com>
 <80F05A66-6943-499A-B402-96249953CD15@gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <80F05A66-6943-499A-B402-96249953CD15@gmail.com>
X-Url: http://acmel.wordpress.com
User-Agent: Mutt/1.5.23 (2014-03-12)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

Em Fri, Jan 08, 2016 at 07:47:03AM +0900, Namhyung Kim escreveu:
> On January 8, 2016 7:00:35 AM GMT+09:00, Stephane Eranian <eranian@google.com> wrote:
> >On Thu, Jan 7, 2016 at 1:59 PM, Arnaldo Carvalho de Melo
> ><acme@kernel.org> wrote:
> >> Em Thu, Jan 07, 2016 at 01:56:14PM -0800, Stephane Eranian escreveu:
> >>> 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.
> >>
> >> I agree, would consider applying a patch that provides the option but
> >> does not do this by default.
> >>
> >I agree, not the default.
> 
> Hi Stephane,
> 
> Please see
> 
> https://lkml.org/lkml/2015/3/22/249


Oops, Stephane, please try this, so that we can finally merge it :-\

- Arnaldo