Re: [PATCH 3/3] drm: Add CRTC_GET_SEQUENCE and CRTC_QUEUE_SEQUENCE ioctls

From: Ville Syrjälä
Date: Thu Jul 06 2017 - 14:59:32 EST


On Thu, Jul 06, 2017 at 11:22:43AM -0700, Keith Packard wrote:
> Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> writes:
>
> > I was mostly thinking of the 'seq = query(); wait(seq + n);' pattern
> > where we can avoid doing the full update more than once if we enable
> > the interrupt already during the query.
>
> Don't we still wait 5 seconds before disabling vblank? In that case, the
> chances of hitting an idle vblank are pretty slim if the application is
> actually busy.

With the disable_immediate thing we only wait until the next vblank
before disabling the irq again.

--
Ville Syrjälä
Intel OTC