From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753233AbbDAJDW (ORCPT ); Wed, 1 Apr 2015 05:03:22 -0400 Received: from e28smtp08.in.ibm.com ([122.248.162.8]:34864 "EHLO e28smtp08.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751740AbbDAJDT (ORCPT ); Wed, 1 Apr 2015 05:03:19 -0400 Message-ID: <551BB43E.5070600@linux.vnet.ibm.com> Date: Wed, 01 Apr 2015 14:32:54 +0530 From: Anshuman Khandual User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.6.0 MIME-Version: 1.0 To: Linux PPC dev , Linux Kernel Mailing List CC: Sukadev Bhattiprolu , Michael Ellerman , Arnaldo Carvalho de Melo , "ak@linux.intel.com" Subject: perf report broken for branch stack samples Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15040109-0029-0000-0000-000005236054 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, perf report is not showing up the branch stack sample results in the from_symbol ---> to_symbol format even if the perf.data file has got the samples (through 'perf record -b ' session). Perf report still displays the generic event based relative symbol classification as usual. This problem can also be seen on X86. I wonder whether there is any semantics change in the way perf report auto detects branch stack samples in the perf.data file and reports in the intended format. After doing a git bisect session, this following commit seems to have changed the perf report behavior. commit fa94c36c29ed8bb4749b5fd7ea51a593f673dcef Author: Andi Kleen Date: Wed Nov 12 18:05:22 2014 -0800 perf report: Add --branch-history option Add a --branch-history option to perf report that changes all the settings necessary for using the branches in callstacks. This is just a short cut to make this nicer to use, it does not enable any functionality by itself. v2: Change sort order. Rename option to --branch-history to be less confusing. v3: Updates v4: Fix conflict with newer perf base v5: Port to latest tip v6: Add more comments. Remove CCKEY_ADDRESS setting. Remove unnecessary branch_mode setting. Use a boolean. Signed-off-by: Andi Kleen Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lkml.kernel.org/r/1415844328-4884-5-git-send-email-andi@firstfloor.org Signed-off-by: Arnaldo Carvalho de Melo I dont have much context of this change but it seems to be using branch records along with call chain data (provided you have used both -b/-j and -g option during perf record) to display better control flow graph ? But then if we have just used -b and not -g then it should still give us the previous output what we used to get. Regards Anshuman