[Mesa-dev] [PATCH 3/5] glx/dri3: Request non-vsynced Present for swapinterval zero. (v2)

[Mario Kleiner]

Restores proper immediate tearing swap behaviour for
OpenGL bufferswap under DRI3/Present.

Cc: "10.3 10.4" <mesa-stable at lists.freedesktop.org>

v2: Add Frank Binns signed off by for his original earlier
patch from April 2014, which is identical to this one, and
Chris Wilsons reviewed tag from May 2014 for that patch, ergo
also for this one.

Signed-off-by: Frank Binns <frank.binns at imgtec.com>
Signed-off-by: Mario Kleiner <mario.kleiner.de at gmail.com>
Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 src/glx/dri3_glx.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/glx/dri3_glx.c b/src/glx/dri3_glx.c
index 5796491..c53be1b 100644
--- a/src/glx/dri3_glx.c
+++ b/src/glx/dri3_glx.c
@@ -1518,6 +1518,7 @@ dri3_swap_buffers(__GLXDRIdrawable *pdraw, int64_t target_msc, int64_t divisor,
    xcb_connection_t *c = XGetXCBConnection(dpy);
    struct dri3_buffer *back;
    int64_t ret = 0;
+   uint32_t options = XCB_PRESENT_OPTION_NONE;
 
    unsigned flags = __DRI2_FLUSH_DRAWABLE;
    if (flush)
@@ -1557,6 +1558,9 @@ dri3_swap_buffers(__GLXDRIdrawable *pdraw, int64_t target_msc, int64_t divisor,
       if (target_msc == 0)
          target_msc = priv->msc + priv->swap_interval * (priv->send_sbc - priv->recv_sbc);
 
+      if (priv->swap_interval == 0)
+          options |= XCB_PRESENT_OPTION_ASYNC;
+
       back->busy = 1;
       back->last_swap = priv->send_sbc;
       xcb_present_pixmap(c,
@@ -1570,7 +1574,7 @@ dri3_swap_buffers(__GLXDRIdrawable *pdraw, int64_t target_msc, int64_t divisor,
                          None,                                 /* target_crtc */
                          None,
                          back->sync_fence,
-                         XCB_PRESENT_OPTION_NONE,
+                         options,
                          target_msc,
                          divisor,
                          remainder, 0, NULL);
-- 
1.9.1