From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755029Ab2JBQaJ (ORCPT ); Tue, 2 Oct 2012 12:30:09 -0400 Received: from one.firstfloor.org ([213.235.205.2]:42266 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754891Ab2JBQaH (ORCPT ); Tue, 2 Oct 2012 12:30:07 -0400 Date: Tue, 2 Oct 2012 18:30:02 +0200 From: Andi Kleen To: Jiri Olsa Cc: Andi Kleen , linux-kernel@vger.kernel.org, Arnaldo Carvalho de Melo , Peter Zijlstra , Ingo Molnar , Paul Mackerras , Corey Ashford , Frederic Weisbecker , "Paul E. McKenney" , David Ahern , Namhyung Kim Subject: Re: [PATCHv2 00/14] perf diff: Factor diff command Message-ID: <20121002163002.GD16230@one.firstfloor.org> References: <1348744175-11115-1-git-send-email-jolsa@redhat.com> <20120927213102.GO16230@one.firstfloor.org> <20121001081631.GB991@krava.brq.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20121001081631.GB991@krava.brq.redhat.com> User-Agent: Mutt/1.4.2.2i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > > Some minor issues I ran into (but no show stoppers): > > - The error messages for bad -c expressions could be better > > - I found the requirement for no space after -c unintuitive. > > I'll see to that > > > - It would be nice to have support for doing the bucketizing per line > > instead of per function. With a large function and/or inlining > > it's sometimes hard to identify the actual problem > > Acme recently added this for perf report. > > hm, I missed this one.. hopefully it should be no problem to add it Here's more issues I found (again no show stopper): For example you have a spinlock problem with different spinlock callers that you want to handle. Since the spinlocks are own functions which are mixed together cannot be easily ratiod. This is probably a bit hard to handle, but one way would be to use a variant of the inclusive reporting Arun recently submitted. Define groups of callers that have a combined cost including all callees. Use this as the diff unit. I really liked the oprofile behaviour of attributing lock costs to the caller by default. With that it would just work. The other problem I ran into is that perf archive doesn't seem to work very well with kernels, so it's hard to move profiles from different kernels around to diff them (e.g. for a performance regression) One way around this would be options to diff to specify the vmlinux etc. manually -Andi