From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758428Ab3KOLw6 (ORCPT ); Fri, 15 Nov 2013 06:52:58 -0500 Received: from merlin.infradead.org ([205.233.59.134]:50459 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753983Ab3KOLwx (ORCPT ); Fri, 15 Nov 2013 06:52:53 -0500 Date: Fri, 15 Nov 2013 12:52:45 +0100 From: Peter Zijlstra To: Ingo Molnar Cc: Stephane Eranian , LKML , Jiri Olsa , "mingo@elte.hu" , David Ahern , "ak@linux.intel.com" , Arnaldo Carvalho de Melo , Namhyung Kim Subject: Re: [BUG] perf stat: explicit grouping yields unexpected results Message-ID: <20131115115245.GD10456@twins.programming.kicks-ass.net> References: <20131115063457.GB12442@gmail.com> <20131115103405.GA18264@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20131115103405.GA18264@gmail.com> User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 15, 2013 at 11:34:05AM +0100, Ingo Molnar wrote: > That brings up an interesting question: what is better for users, if > we schedule as many as we can and say 'not supported' to the rest > (current behavior), or if we fail the whole group? > > I'd say that the default behavior should be what Jiri implemented: get > the most out of the situation and inform. But you are right in that > 'forcing' all elements of a group to be valid should be possible as > well - if a special perf stat option or event format is used. So I don't agree, but if you want to keep this IMO weird behaviour at least WARN about it in big blinking neon letters that the user isn't getting what he asked for.