[PATCH 15/27] drm/i915: nonblocking commit

[Maarten Lankhorst]

Op 08-06-16 om 14:19 schreef Daniel Vetter:
> Simply split intel_atomic_commit in half and place the new
> nonblocking commit helpers at the right spots.
>
> NOTE: There's still trouble with obj->frontbuffer bits getting mangled
> when pipelining atomic commits.
>
> v2:
> - Remove the check for nonblocking which returned -EINVAL.
> - Do wait for requests in the worker thread before committing
>   hw state.
>
> v3: Move hw_done after the optimize_wm/post_plane_update step, plus
> add FIXME comment how to fix that up again properly.
>
> v4: Update FIXME for intel_atomic_commit - more stuff works now.
This is not a good idea for now, there are still some places in modeset that rely on being run synchronously.
Lockdep will be unhappy and some WARN_ONs will trigger.

I think that you should first only allow nonblocking page flips, and return -EBUSY if intel_state->modeset is set.

~Maarten