From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jiri Olsa Subject: Re: Two questions on perf dwarf callchains Date: Thu, 30 Jan 2014 16:40:47 +0100 Message-ID: <20140130154047.GB1827@krava.brq.redhat.com> References: <1389954083.1125.23.camel@nb-andreolini.mat.unimo.it> <20140129111844.GA1869@krava.brq.redhat.com> <1391008146.1316.8.camel@nb-andreolini.mat.unimo.it> <20140130114751.GB1161@krava.brq.redhat.com> <1391092999.1111.3.camel@nb-andreolini.mat.unimo.it> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mx1.redhat.com ([209.132.183.28]:43778 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753089AbaA3Pkt (ORCPT ); Thu, 30 Jan 2014 10:40:49 -0500 Content-Disposition: inline In-Reply-To: <1391092999.1111.3.camel@nb-andreolini.mat.unimo.it> Sender: linux-perf-users-owner@vger.kernel.org List-ID: To: Mauro Andreolini Cc: linux-perf-users@vger.kernel.org On Thu, Jan 30, 2014 at 03:43:19PM +0100, Mauro Andreolini wrote: > > zero's are taken care by: > > http://marc.info/?t=138909914500003&r=1&w=2 > > within following patchset: > > http://marc.info/?l=linux-kernel&m=138909914404574&w=2 > > > which implements libdw dwarf unwind.. you might > > actualy want to try it, it seems to be little faster > > than libunwind unwinder > Since I do not yet have elfutils 0.158 installed, I tried > to apply the single patch both to linux-3.12 and to the kernel you > pointed me at, and used perf with the libunwind unwinder. With the 3.12 > kernel I get segfaults on perf report; with the 3.13 branch zeroes are > still present. Maybe I messed up. > I think I'll wait for the newest elfutils and give a shot ad the > libdw unwinder. I use elfutils git tree ;-) git://git.fedorahosted.org/git/elfutils.git and the latest patchset (recently rebased) is in here: git://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git perf/core_libdw_unwind jirka