From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755428Ab1HCMLd (ORCPT ); Wed, 3 Aug 2011 08:11:33 -0400 Received: from mail-qw0-f46.google.com ([209.85.216.46]:42881 "EHLO mail-qw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755202Ab1HCML0 (ORCPT ); Wed, 3 Aug 2011 08:11:26 -0400 Date: Wed, 3 Aug 2011 14:11:21 +0200 From: Frederic Weisbecker To: Peter Zijlstra Cc: mingo@redhat.com, hpa@zytor.com, eranian@google.com, linux-kernel@vger.kernel.org, acme@redhat.com, robert.richter@amd.com, tglx@linutronix.de, cjashfor@linux.vnet.ibm.com, mingo@elte.hu, linux-tip-commits@vger.kernel.org Subject: Re: [tip:perf/urgent] perf sched: Fix list of events, dropping unsupported ':r' modifier Message-ID: <20110803121119.GC5768@somewhere.redhat.com> References: <1312369161.1147.292.camel@twins> <20110803113706.GA5768@somewhere.redhat.com> <1312371741.1147.301.camel@twins> <20110803115703.GB5768@somewhere.redhat.com> <1312373135.1147.308.camel@twins> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1312373135.1147.308.camel@twins> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Aug 03, 2011 at 02:05:35PM +0200, Peter Zijlstra wrote: > On Wed, 2011-08-03 at 13:57 +0200, Frederic Weisbecker wrote: > > On Wed, Aug 03, 2011 at 01:42:21PM +0200, Peter Zijlstra wrote: > > > On Wed, 2011-08-03 at 13:37 +0200, Frederic Weisbecker wrote: > > > > On Wed, Aug 03, 2011 at 12:59:21PM +0200, Peter Zijlstra wrote: > > > > > On Fri, 2011-01-14 at 07:25 +0000, tip-bot for Stephane Eranian wrote: > > > > > > Looks to me like the :r modifier is not supported anymore, so remove it from > > > > > > the list of events. > > > > > > > > > > acme, why is that anyway? -R is a fun way to save some typing, but not > > > > > supporting :r anymore takes away the option of not getting > > > > > PERF_SAMPLE_RAW output for every event. > > > > > > > > Because it was very non obvious for people to select this -R or :r > > > > every time they wanted to use trace events for tracing. I think > > > > there was complaints about that. Moreover nobody seemed to use > > > > trace events for non-tracing (perf report, top, annotate, ...) > > > > so we decided to always have RAW records so that it works for > > > > every cases...unless we lose events because of that. > > > > > > > > We can still bring an option to force disabling of raw records. > > > > > > That just doesn't compute, they still have to use -R, so what's the harm > > > in also having :r? > > > > Nope -R is the default/forced behaviour already. > > But even if it wasn't I don't see much the point of ":r". Who wants > > to run two trace events and only record the traces of one? > > [root@westmere linux-2.6]# grep raw_samples tools/perf/builtin-record.c | head -1 > static bool raw_samples = false; > > is what tip/master is showing me.. Look at tools/perf/util/parse-events.c:parse_single_tracepoint_event() > > > > Also taking away options just because it confuses people sounds like > > > gnome, lets just not go there. > > > > You're right but options should be there only to be able to override > > sane default common uses. And not the opposite. And the common use > > of trace events is for tracing. > > > > We should rather enable tracing by default and disable it through > > an option. Like --no-trace or so. > > you smoking some expensive stuff, right?