Subject: Re: [PATCH][RFC] tracing: Enable tracepoints via module parameters
From: Steven Rostedt <rostedt@goodmis.org>
To: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: linux-kernel@vger.kernel.org, Ingo Molnar <mingo@elte.hu>,
        Frederic Weisbecker <fweisbec@gmail.com>,
        Rusty Russell <rusty@rustcorp.com.au>,
        Yuanhan Liu <yuanhan.liu@linux.intel.com>,
        chris <chris@chris-wilson.co.uk>
In-Reply-To: <20110309000753.GA27729@Krystal>
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	 <20110309000753.GA27729@Krystal>
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Date: Tue, 08 Mar 2011 19:14:17 -0500
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On Tue, 2011-03-08 at 19:07 -0500, Mathieu Desnoyers wrote:

> So what you are saying here is that modifying /etc/modprobe.d/ is the actual
> interface you propose presenting to the end-users to control their tracepoints ?

If you want to have them enabled on boot, sure.

> Maybe I am missing something, but this interface seems to lack the layer of
> finish we might want to put into a user-visible API. I don't really see how
> distributions can hope to automate any of this for their end-user without making
> a mess of the /etc/modprobe.d/ they ship with.

What distros enable tracepoints by default?

If you want to enable a tracepoint on module load simply do:

 modprobe mymod trace_my_tracepoint=1

Otherwise modify your modprobe.d directory. This is the way users have
been doing module parameters for years.

That's pretty simple to me.

-- Steve


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