flip_test: add comment about the race between flip vs. vblank events

Signed-off-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Imre Deak 2012-10-22 20:40:07 +03:00 committed by Daniel Vetter
parent 7f32adc6c5
commit c7dd1dcdd9

View File

@ -444,6 +444,11 @@ static unsigned int run_test_step(struct test_output *o)
if (o->flags & TEST_VBLANK_ABSOLUTE) if (o->flags & TEST_VBLANK_ABSOLUTE)
target_seq += o->vblank_state.last_seq; target_seq += o->vblank_state.last_seq;
/*
* It's possible that we don't have a pending flip here, in case both
* wf-vblank and flip were scheduled and the wf-vblank event was
* delivered earlier. The same applies to vblank events w.r.t flip.
*/
do_flip = (o->flags & TEST_FLIP) && !(o->pending_events & EVENT_FLIP); do_flip = (o->flags & TEST_FLIP) && !(o->pending_events & EVENT_FLIP);
do_vblank = (o->flags & TEST_VBLANK) && do_vblank = (o->flags & TEST_VBLANK) &&
!(o->pending_events & EVENT_VBLANK); !(o->pending_events & EVENT_VBLANK);