From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932719Ab1D2TYE (ORCPT ); Fri, 29 Apr 2011 15:24:04 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:44337 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932481Ab1D2TYC (ORCPT ); Fri, 29 Apr 2011 15:24:02 -0400 Date: Fri, 29 Apr 2011 21:23:47 +0200 From: Ingo Molnar To: David Ahern Cc: mingo@redhat.com, hpa@zytor.com, acme@redhat.com, linux-kernel@vger.kernel.org, fweisbec@gmail.com, a.p.zijlstra@chello.nl, tglx@linutronix.de, linux-tip-commits@vger.kernel.org Subject: Re: [tip:perf/stat] perf stat: Fail softly on unsupported events Message-ID: <20110429192347.GA15068@elte.hu> References: <4DBACC5C.1020502@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4DBACC5C.1020502@gmail.com> User-Agent: Mutt/1.5.20 (2009-08-17) X-ELTE-SpamScore: -2.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.0 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.3.1 -2.0 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * David Ahern wrote: > > > On 04/29/11 08:27, tip-bot for Ingo Molnar wrote: > > Commit-ID: 370faf1dd0461ad811852c8abbbcd3d73b1e4fc4 > > Gitweb: http://git.kernel.org/tip/370faf1dd0461ad811852c8abbbcd3d73b1e4fc4 > > Author: Ingo Molnar > > AuthorDate: Fri, 29 Apr 2011 16:11:03 +0200 > > Committer: Ingo Molnar > > CommitDate: Fri, 29 Apr 2011 16:22:33 +0200 > > > > perf stat: Fail softly on unsupported events > > > > David Ahern reported this perf stat failure: > > > >> # /tmp/build-perf/perf stat -- sleep 1 > >> Error: stalled-cycles-frontend event is not supported. > >> Fatal: Not all events could be opened. > >> > >> This is a Dell R410 with an E5620 processor. > > > > Fail in a softer fashion on unknown/unsupported events. > > > > Reported-by: David Ahern > > Cc: Peter Zijlstra > > Cc: Arnaldo Carvalho de Melo > > Cc: Frederic Weisbecker > > Link: http://lkml.kernel.org/n/tip-7y40wib8n006io7hjpn1dsrm@git.kernel.org > > Signed-off-by: Ingo Molnar > > --- > > tools/perf/builtin-stat.c | 4 +--- > > 1 files changed, 1 insertions(+), 3 deletions(-) > > > > diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c > > index 9e596ab..c8b535b 100644 > > --- a/tools/perf/builtin-stat.c > > +++ b/tools/perf/builtin-stat.c > > @@ -377,7 +377,7 @@ static int run_perf_stat(int argc __used, const char **argv) > > > > list_for_each_entry(counter, &evsel_list->entries, node) { > > if (create_perf_stat_counter(counter) < 0) { > > - if (errno == EINVAL || errno == ENOSYS) > > + if (errno == EINVAL || errno == ENOSYS || errno == ENOENT) > > continue; > > > > if (errno == EPERM || errno == EACCES) { > > @@ -385,8 +385,6 @@ static int run_perf_stat(int argc __used, const char **argv) > > "\t Consider tweaking" > > " /proc/sys/kernel/perf_event_paranoid or running as root.", > > system_wide ? "system-wide " : ""); > > - } else if (errno == ENOENT) { > > - error("%s event is not supported. ", event_name(counter)); > > This silently ignores events -- including ones that a user requested. I > think a better option is a continue here. > > /tmp/build-perf/perf stat -- sleep 1 > Error: stalled-cycles-frontend event is not supported. > Error: stalled-cycles-backend event is not supported. Ok. Got time to send a patch for that, which prints whichever message you find the most intuitive? Perhaps word it as: Info: stalled-cycles-frontend event is not supported by the kernel to not yell 'error!' at users all the time? Thanks, Ingo