[PATCH] dri2: Pass AsyncSwap [vblank_mode=0] requests to the drivers

[Jesse Barnes]

On Wed,  8 Jun 2011 19:06:11 +0100
Chris Wilson <chris at chris-wilson.co.uk> wrote:

> Currently, the midlayer dri2 code intercepts vblank_mode=0 SwapBuffers
> and converts it to a CopyRegion request. This prevents the backend from
> doing anything meaningful in this case and typically ends up being
> vsync'ed since the drivers cannot distinguish it from a regular
> CopyRegion request.
> 
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Jesse Barnes <jbarnes at virtuousgeek.org>
> Cc: Kristian Høgsberg <krh at bitplanet.net>
> ---
> 
> Sigh... I broke the patch with a last minute name change. Please pretend
> you never saw the previous patch.

In hindsight, it would have been better if DRI2 never had a CopyRegion
hook and just let the driver decide what to do given all the params
(i.e. a very generic Swap hook).

But we don't have that and this looks like a nice addition.  It would
be good to add a blurb to the header file about the hook though, since
it could be easily confused with a hook that's supposed to schedule
something and return immediately or something, rather than a "swap now,
tearing be damned" hook.

-- 
Jesse Barnes, Intel Open Source Technology Center