add a bunch of #ifdef DRM_VBLANK_DEBUG debugging to the vblank code.
add a bunch of #ifdef DRM_VBLANK_DEBUG debugging to the vblank code.

I'm sick of writing debugging for the refcounting every damned time this
fragile as hell code breaks.

orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars