[Intel-gfx] [PATCH] drm: Make the decision to keep vblank irq enabled earlier

[Chris Wilson]

On Fri, Mar 24, 2017 at 04:16:28AM +0100, Mario Kleiner wrote:
> Looks good to me. As a further optimization, i think we could move
> the vblank_disable_fn() call outside/below the
> spin_unlock_irqrestore for event_lock, as vblank_disable_fn()
> doesn't need any locks held at call time, so slightly reduce
> event_lock hold time. Don't know if it is worth it.

Hmm, I was cautious since I don't trust myself around the vbl spinlocks.
But yes, the vblank->refcount is controlled by vbl_lock and that is
checked inside the disable callback, so we can move it out from the
vblank_event_lock.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre