From mboxrd@z Thu Jan  1 00:00:00 1970
From: Chris Wilson <chris@chris-wilson.co.uk>
Subject: Re: [PATCH] drm/i915: Add aub debug support for kernel
Date: Sun, 07 Nov 2010 16:03:17 +0000
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Oh my, this turns out to be quite hacky indeed...

if (i915_trace_on_load) {
	const struct ftrace_event_call enable_list[] = {
#define EVENT(name) event_call_##name
		&EVENT(i915_reg),
		NULL,
	}, *call = enable_list;
	do {
		if ((*call)->class->reg(*call, TRACE_REG_REGISTER) == 0)
			(*call)->flags |= TRACE_EVENT_FL_ENABLED;
		else
			DRM_DEBUG("failed to enable tracepoint '%s'\n",
				(*call)->name);
	} while (*++call);
}

[Not even compile tested! ;)]

That would seem to do the trick. The alternative would be to override the
use of trace_event_raw_init in the include/trace/ftrace.h macros. In light
of that the above seems much simpler.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre