From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752630AbbJTPAS (ORCPT ); Tue, 20 Oct 2015 11:00:18 -0400 Received: from mail.kernel.org ([198.145.29.136]:52125 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751735AbbJTPAQ (ORCPT ); Tue, 20 Oct 2015 11:00:16 -0400 Date: Tue, 20 Oct 2015 12:00:10 -0300 From: Arnaldo Carvalho de Melo To: "Liang, Kan" Cc: "jolsa@kernel.org" , "ak@linux.intel.com" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH 1/1] perf,tools: fix core dump caused by per-socket/core system-wide stat Message-ID: <20151020150010.GE5119@kernel.org> References: <1444388363-35936-1-git-send-email-kan.liang@intel.com> <20151009205924.GA19587@krava.landal.opennet> <37D7C6CF3E00A74B8858931C1DB2F07701972415@SHSMSX103.ccr.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <37D7C6CF3E00A74B8858931C1DB2F07701972415@SHSMSX103.ccr.corp.intel.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: X-Mailing-List: linux-kernel@vger.kernel.org Em Mon, Oct 19, 2015 at 10:22:51PM +0000, Liang, Kan escreveu: > Hi Arnaldo > > Here is one more fix for perf/core need to be pulled. Thanks for the reminder, tried to reproduce on a two socket system, couldn't, but the fix is obvious enough, thanks, applied. - Arnaldo > Thanks, > Kan > > > > > On Fri, Oct 09, 2015 at 06:59:23AM -0400, kan.liang@intel.com wrote: > > > From: Kan Liang > > > > > > Perf will core dump if --per-socket/core -a are applied for perf stat. > > > > > > The root cause is that cpu_map__build_map set refcnt of evlist's > > > cpu_map to 1. > > > It should set refcnt for the newly created cpu_map, not evlist's > > > cpu_map. > > > > > > Here is the example: > > > > > > perf stat -e cycles --per-socket -a sleep 1 > > > > > > Performance counter stats for 'system wide': > > > > > > S0 36 30,196,257 cycles > > > S1 28 15,823,536 cycles > > > > > > 1.001126828 seconds time elapsed > > > > > > *** Error in `./perf': corrupted double-linked list: > > > 0x00000000021f9090 > > > *** > > > ======= Backtrace: ========= > > > /lib64/libc.so.6[0x3002e7bbe7] > > > /lib64/libc.so.6[0x3002e7d2b5] > > > ./perf(perf_evsel__delete+0x28)[0x485bdd] > > > ./perf[0x4800e8] > > > ./perf(perf_evlist__delete+0x5e)[0x482cd5] > > > ./perf(cmd_stat+0xf25)[0x432328] > > > ./perf[0x4768e0] > > > ./perf[0x476ad6] > > > ./perf[0x476b41] > > > ./perf(main+0x1d0)[0x476db2] > > > /lib64/libc.so.6(__libc_start_main+0xf5)[0x3002e21b45] > > > ./perf[0x4202c5] > > > > > > Signed-off-by: Kan Liang > > > --- > > > tools/perf/util/cpumap.c | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > diff --git a/tools/perf/util/cpumap.c b/tools/perf/util/cpumap.c index > > > c51c29f..dfc1f0b 100644 > > > --- a/tools/perf/util/cpumap.c > > > +++ b/tools/perf/util/cpumap.c > > > @@ -284,7 +284,7 @@ static int cpu_map__build_map(struct cpu_map > > *cpus, struct cpu_map **res, > > > /* ensure we process id in increasing order */ > > > qsort(c->map, c->nr, sizeof(int), cmp_ids); > > > > > > - atomic_set(&cpus->refcnt, 1); > > > + atomic_set(&c->refcnt, 1); > > > > ouch ;-) > > > > Acked-by: Jiri Olsa > > > > thanks, > > jirka