Re: [PATCH] ftrace: add kernel command line graph function filtering

[Steven Rostedt <rostedt@goodmis.org>]

On Mon, 2009-10-12 at 11:09 +0200, Frédéric Weisbecker wrote:
> 2009/10/12 Stefan Assmann <sassmann@redhat.com>:
> > From 894e934e782ddaa33eb6d156d8326cdf479b5f62 Mon Sep 17 00:00:00 2001
> > From: Stefan Assmann <sassmann@redhat.com>
> > Date: Mon, 12 Oct 2009 09:11:47 +0200
> > Subject: [PATCH] ftrace: add kernel command line graph function filtering
> >
> > Add a command line parameter to allow limiting the function graphs that
> > are traced on boot up, when ftrace=function_graph is specified.
> >
> > This patch adds the following command line option:
> > ftrace_graph_filter=function-list
> 
> 
> If we use this parameter, we undoubtedly want to launch the function
> graph tracer.
> I'd then suggest to arm ftrace=function_graph automatically if we have
> ftrace_graph_filter
> set.
> 

Actually, I disagree. I may just be lazy, and want to set up the
function graph to a particular set of functions. It doesn't mean I want
to run the function_graph tracer on boot up.

This is the same reason I don't automatically set up ftrace=function
when the filter and notrace functions are set.

-- Steve