From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753740AbbKCBqK (ORCPT ); Mon, 2 Nov 2015 20:46:10 -0500 Received: from mail.kernel.org ([198.145.29.136]:46440 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751313AbbKCBqE (ORCPT ); Mon, 2 Nov 2015 20:46:04 -0500 Date: Mon, 2 Nov 2015 22:46:00 -0300 From: Arnaldo Carvalho de Melo To: Namhyung Kim Cc: Brendan Gregg , Ingo Molnar , Peter Zijlstra , Jiri Olsa , LKML , David Ahern , Frederic Weisbecker , Andi Kleen , Kan Liang Subject: Re: [RFC/PATCH 0/4] perf report: Support folded callchain output (v2) Message-ID: <20151103014600.GH21609@kernel.org> References: <1446469069-16223-1-git-send-email-namhyung@kernel.org> <20151102213021.GA21609@kernel.org> <20151102221204.GB10949@danjae.kornet> <20151102222842.GB21609@kernel.org> <20151102224927.GA11498@danjae.kornet> <20151102230436.GD21609@kernel.org> <20151102234606.GB11498@danjae.kornet> <20151103004647.GE21609@kernel.org> <20151103013535.GD11498@danjae.kornet> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20151103013535.GD11498@danjae.kornet> 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 Tue, Nov 03, 2015 at 10:35:35AM +0900, Namhyung Kim escreveu: > On Mon, Nov 02, 2015 at 09:46:47PM -0300, Arnaldo Carvalho de Melo wrote: > > Em Tue, Nov 03, 2015 at 08:46:06AM +0900, Namhyung Kim escreveu: > > > On Mon, Nov 02, 2015 at 08:04:36PM -0300, Arnaldo Carvalho de Melo wrote: > > > > I still think that this is a 'perf report' thing, but one that is > > > > centered in callchains, and that is to be consumed by scripts, not > > > > humans. > > > > > Agreed. > > > > > I'm just looking for a way to support it with minimal change. :) > > > > Hey, me too. A --no-hists flag looks like a quickie, no need to isolate > > callchain code, or anything like that, just one long option switch and > > we get what we need. > > Hmm.. okay. Let me think about the --no-hists flags then. > > What do you want to do if the --no-hists flags is used without folded > callchain mode or other than --stdio? What the user asked it to, to not show what hist_entry__snprintf() produces, i.e. just the callchains. Its left to the user to decide if that output is good for whatever purpose it has in mind. We, from this discussion, know that suppressing it when using with folded callchains, is useful at least for Brendan's scripts :-) > And if you want to print other info in the callchains, what would be > the output of non-folded mode? > I think the simplest solution would be supporting the folded mode only > and error out other cases. Is it ok to you? Well, the other info, if it comes at the end, may even be useful in non folded mode, no? If it is not, then the user will not use it, i.e. some combinations may not produce useful results, but if we want to have more flexibility to support usecases like Brendan's, and I think we want, without making the existing code overly complex, then why not? - Arnaldo