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Date: Tue, 25 Aug 2009 12:22:15 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>, Steven Rostedt <rostedt@goodmis.org>,
       Frederic Weisbecker <fweisbec@gmail.com>,
       LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] tracing/profile: Fix profile_disable vs module_unload
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* Peter Zijlstra <peterz@infradead.org> wrote:

> On Tue, 2009-08-25 at 11:05 +0200, Ingo Molnar wrote:
> > * Peter Zijlstra <peterz@infradead.org> wrote:
> > 
> > > Ah, my bad, I was thikning tracepoint_probe_register() was the 
> > > thing that registered the tracepoint itself, not the callback.
> > > 
> > > Ok, then what's the problem?, don't do modules that consume their 
> > > own tracepoints, seems simple enough.
> > 
> > is this a reasonable restriction? I dont see any reason why the 
> > act of defining and providing a tracepoint should be exclusive 
> > of the ability to make use of it.
> 
> It doesn't make sense to me, you don't need your own tracepoints 
> because you generate the events yourself, you already have them.

For a reasonable large subsystem/driver i can very well imagine this 
to happen: why should the subsystem add _another_ layer of callbacks 
if it can reuse the generic tracepoint code and register itself to 
those?

	Ingo