From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757680Ab0CaKhV (ORCPT ); Wed, 31 Mar 2010 06:37:21 -0400 Received: from mx1.redhat.com ([209.132.183.28]:3526 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752003Ab0CaKhT (ORCPT ); Wed, 31 Mar 2010 06:37:19 -0400 Date: Wed, 31 Mar 2010 12:36:54 +0200 From: Jiri Olsa To: Frederic Weisbecker Cc: Steven Rostedt , linux-kernel@vger.kernel.org, Ingo Molnar Subject: Re: [PATCHv3 0/2] tracing: function graph output for preempt/irqs-off tracers Message-ID: <20100331103654.GB2152@jolsa.lab.eng.brq.redhat.com> References: <1269606723-12439-1-git-send-email-jolsa@redhat.com> <1269615239.19685.78.camel@gandalf.stny.rr.com> <20100329111701.GC1715@jolsa> <1269875347.19685.4492.camel@gandalf.stny.rr.com> <20100329152154.GF1715@jolsa> <1269877299.19685.4527.camel@gandalf.stny.rr.com> <20100331073738.GA2152@jolsa.lab.eng.brq.redhat.com> <20100331080154.GA5229@nowhere> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100331080154.GA5229@nowhere> User-Agent: Mutt/1.5.20 (2009-08-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Mar 31, 2010 at 10:01:57AM +0200, Frederic Weisbecker wrote: > On Wed, Mar 31, 2010 at 09:37:38AM +0200, Jiri Olsa wrote: > > On Mon, Mar 29, 2010 at 11:41:39AM -0400, Steven Rostedt wrote: > > > On Mon, 2010-03-29 at 17:21 +0200, Jiri Olsa wrote: > > > > > > > > Understand what I'm trying to ask? > > > > > > > > ok, so what you mean is: > > > > - dont clear the max_tr and > > > > - add function graph events. > > > > > > > > So when the tracing_enabled and display-graph are disabled we will > > > > get events output rather than 'unknown event' output... right? > > > > > > Right, although when the display-graph is disabled, we lose the /* */ > > > but that's fine. > > > > ok, I have it done, but found another issue.. > > > > It's the tracer_flags which governs the tracer output. As I'm using > > the function_graph tracer output functions, they follow function_graph > > tracer's flags settings.. > > > > My first idea was a change that would allow tracer using flags > > of other tracers.. so, when enabling irqsoff tracer the function_graph > > tracer's options would become available. > > > > I made the patch but got to the set_flag function which can be overloaded > > by tracer. So I'd need to remember the flags's tracer, and it does > > not seem right.. :) > > > > any ideas? > > > > thanks, > > jirka > > > Hehe :) > > I don't think we need such a feature. I doubt anybody > is going to play with the options granularity of the function > graph tracer there. > > We should rather focus on what is useful to display for irqsoff > tracing, which means we need every function graph options set except > funcgraph-overrun that is only there to debug the tracer > itself (I haven't tried it for a while BTW). > > What you can do is to save the function graph tracer options > when the irqsoff tracer starts, then overwrite them, and eventually > restore the previous values when the irqsoff reset callback is called. > > Or preferably... > > Another solution, a bit more proper, is to sanitize a bit the function > graph tracer printing helpers by pushing the options as a parameter to > them. > > So the function graph tracer can call them by passing the function graph > tracer options, and the irqsoff tracer or any other tracer can call them > with its own options. ok, this one looks good :) thanks jirka