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 12:47:51 +0100 Message-ID: <20140130114751.GB1161@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> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mx1.redhat.com ([209.132.183.28]:2838 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752646AbaA3Lr4 (ORCPT ); Thu, 30 Jan 2014 06:47:56 -0500 Content-Disposition: inline In-Reply-To: <1391008146.1316.8.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 Wed, Jan 29, 2014 at 04:09:06PM +0100, Mauro Andreolini wrote: > Il giorno mer, 29/01/2014 alle 12.18 +0100, Jiri Olsa ha scritto: SNIP > | new_do_write > | _IO_do_write@@GLIBC_2.2.5 > | _IO_file_overflow@@GLIBC_2.2.5 > | print_many_per_line > | print_current_files > | print_dir > | main > | __libc_start_main > | _start > | 0x0 <---- HERE 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 > > I also get an occasional screw in the dynamic linker code path: > > 5.26% ls [kernel.kallsyms] [k] > lock_release > | > --- lock_release > __mem_cgroup_try_charge > mem_cgroup_charge_common > mem_cgroup_newpage_charge > do_wp_page > handle_mm_fault > __do_page_fault > do_page_fault > do_async_page_fault > async_page_fault > __init_cpu_features > 0x7fd2357470de <---- HERE not sure if that's just untranslatable part (.plt .got?) or an error.. need to be checked some day ;-) jirka