[Mesa-dev] [PATCH 1/2] loader/dri3: Only wait for back buffer fences in dri3_get_buffer

[Michel Dänzer]

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

We don't need to wait before drawing to the fake front buffer, as front
buffer rendering by definition is allowed to produce artifacts.

Fixes hangs in some cases when re-using the fake front buffer, due to it
still being busy (i.e. in use for presentation).

Cc: mesa-stable at lists.freedesktop.org
Bugzilla: https://bugs.freedesktop.org/106404
Bugzilla: https://bugs.freedesktop.org/107757
Signed-off-by: Michel Dänzer <michel.daenzer at amd.com>
---
 src/loader/loader_dri3_helper.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/loader/loader_dri3_helper.c b/src/loader/loader_dri3_helper.c
index 91bad86afd8..6c162553f33 100644
--- a/src/loader/loader_dri3_helper.c
+++ b/src/loader/loader_dri3_helper.c
@@ -1819,7 +1819,9 @@ dri3_get_buffer(__DRIdrawable *driDrawable,
       buffer = new_buffer;
       draw->buffers[buf_id] = buffer;
    }
-   dri3_fence_await(draw->conn, draw, buffer);
+
+   if (buffer_type == loader_dri3_buffer_back)
+      dri3_fence_await(draw->conn, draw, buffer);
 
    /*
     * Do we need to preserve the content of a previous buffer?
-- 
2.19.0.rc1