[PATCH xserver v2] present: Only call present_flip_notify if vblank->queued == FALSE

Michel Dänzer michel at daenzer.net
Mon Nov 28 01:54:58 UTC 2016


From: Michel Dänzer <michel.daenzer at amd.com>

We are no longer using the present_flip_queue list only for presents
which have already been submitted to the driver for page flipping, but
also for those which we are queueing up to be flipped later, marked
with vblank->queued == TRUE. We were incorrectly calling
present_flip_notify for such entries, failing the assertion in
present_flip_notify (or presumably resulting in other undesirable
behaviour with assertions disabled).

Reproduction recipe: Run the JavaFX test case referenced by
https://bugs.freedesktop.org/show_bug.cgi?id=98831#c6 and alt-tab out
of it while it's fullscreen. May take a few attempts to hit the
assertion failure.

Fixes: bab0f450a719 ("present: Fix presentation of flips out of order")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=98854
Signed-off-by: Michel Dänzer <michel.daenzer at amd.com>
---

v2: Add bugzilla reference

 present/present.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/present/present.c b/present/present.c
index a7ca06e..ef89045 100644
--- a/present/present.c
+++ b/present/present.c
@@ -536,7 +536,10 @@ present_event_notify(uint64_t event_id, uint64_t ust, uint64_t msc)
     }
     xorg_list_for_each_entry(vblank, &present_flip_queue, event_queue) {
         if (vblank->event_id == event_id) {
-            present_flip_notify(vblank, ust, msc);
+            if (vblank->queued)
+                present_execute(vblank, ust, msc);
+            else
+                present_flip_notify(vblank, ust, msc);
             return;
         }
     }
-- 
2.10.2



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