Re: [RFC v2 5/8] drm/fence: add in-fences support

[Ville Syrjälä]

On Thu, Apr 28, 2016 at 07:43:16PM +0200, Daniel Vetter wrote:
> On Thu, Apr 28, 2016 at 6:56 PM, Ville Syrjälä
> <ville.syrjala@xxxxxxxxxxxxxxx> wrote:
> >>  - better for tracing, can identify the buffer/fence promptly
> >
> > Can fences be reused somehow while still attached to a plane, or ever?
> > That might cause some oddness if you, say, leave a fence attached to one
> > plane and then do a modeset on another crtc perhaps which needs to turn
> > the first crtc off+on to reconfigure something.
> 
> Fences auto-disappear of course and don't stick around when you
> duplicate the drm_plane_state again. I still don't really get the real
> concerns though ...

Properties that magically change values shouldn't exist IMO. I guess if
you could have write-only properties or something it migth be sensible?

> In the end it's purely a transport question, and
> both ABI ideas work out semantically exactly the same in the end. It's
> just that at least in my opinion FENCE_FD prop is a lot more
> convenient.
> -Daniel
> -- 
> Daniel Vetter
> Software Engineer, Intel Corporation
> +41 (0) 79 365 57 48 - http://blog.ffwll.ch

-- 
Ville Syrjälä
Intel OTC