From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932722AbbDUQqs (ORCPT ); Tue, 21 Apr 2015 12:46:48 -0400 Received: from mail.kernel.org ([198.145.29.136]:39478 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932424AbbDUQqq (ORCPT ); Tue, 21 Apr 2015 12:46:46 -0400 Date: Tue, 21 Apr 2015 13:46:40 -0300 From: Arnaldo Carvalho de Melo To: Namhyung Kim Cc: Ingo Molnar , Peter Zijlstra , Jiri Olsa , LKML , David Ahern , Taeung Song Subject: Re: [PATCH v3] perf tools: Document --children option in more detail Message-ID: <20150421164640.GG11111@kernel.org> References: <1429619311-27916-1-git-send-email-namhyung@kernel.org> <20150421154133.GF11111@kernel.org> <20150421161629.GG8483@danjae.kornet> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150421161629.GG8483@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 Wed, Apr 22, 2015 at 01:16:29AM +0900, Namhyung Kim escreveu: > On Tue, Apr 21, 2015 at 12:41:33PM -0300, Arnaldo Carvalho de Melo wrote: > > > +++ b/tools/perf/Documentation/overhead-calculation.txt > > I think Ingo suggested that you renamed this file to include the word > > "callchain" in it, no? looking at "overhead-calculation" I feel like I > > first have to open it to figure out what kind of overhead is this, > > perhaps it would be better named: > > tools/perf/Documentation/callchain-overhead.txt > > ? > Please see my reply to the Ingo's post. I think he agreed on this name. I still find it confusing for the file name, where there is no context, from just the file name when one does a 'ls tools/perf/Documentatoin' to figure out about what overhead that is referring to. So, perhaps a longer name: tools/perf/Documentation/callchain-overhead-calculation.txt ? Inside perf-{record,top}.txt, yeah, we have context, we know that this is about post processing, formatting, etc. > > > +--no-children option on the command line or by adding 'report.children > > > += false' or 'top.children = false' in the perf config file. > > > > One can as well use the OPTION_FOO shortening mechanism and instead use: > > > > perf report --no-ch > > > > Which is enough to disambiguate it from "--no-column-widths" and "--no-cpu". > > Are you saying that you want to add the short form instead of the full > --no-chlidren name? I think we need to verbose in the manpage at > least and it might not work in the future if some --chxxx option is > added. Perhaps: "--no-children option on the command line or by adding 'report.children = false' or 'top.children = false' in the perf config file. A shorter form on the command line can be used, for instance '--no-ch' is unambiguous at the time of this writing." > > > diff --git a/tools/perf/Documentation/perf-report.txt b/tools/perf/Documentation/perf-report.txt > > > index 4879cf638824..b7bb298deee3 100644 > > > --- a/tools/perf/Documentation/perf-report.txt > > > +++ b/tools/perf/Documentation/perf-report.txt > > > @@ -193,6 +193,7 @@ OPTIONS > > > Accumulate callchain of children to parent entry so that then can > > > show up in the output. The output will have a new "Children" column > > > and will be sorted on the data. It requires callchains are recorded. > > > + See the `overhead calculation' section for more details. > > > > `callchain overhead' > > Do you prefer this name to 'overhead calculation'? For me, it looks It is ok with me "overhead calculation", as mentioned previously in this message, the context in this perf-report.txt file should make it clear that the overhead is about callchains. > like saying about how much overhead will be added if we enabled > callchains at perf record time or processing them at perf report time. Ok. - Arnaldo