[Intel-gfx] [PATCH 1/3] drm/i915: Wait for pending flips in intel_pipe_set_base()

[Chris Wilson]

On Fri, 2 Nov 2012 19:26:37 +0200, Ville Syrjälä <ville.syrjala at linux.intel.com> wrote:
> But now I started to wonder a bit about the performance implications
> of keeping struct_mutex locked for that long...

Unless you are worrying about doing a modeset for every vblank, don't.
We treat modesetting as a rare, stop-the-world event for the time being,
with the emphasis upon making the darn thing reliable. Long term goal
would be to decouple the locks so that we could have indepedent users
on a multi-head device, but for now we can assume that our sole user is
so distracted by the screen going blank to not worry about his
background folding at home task stalling for ~100 ms...

On the other hand, with output slaves it is likely that a render stall
will become more noticeable even for a single user.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre