From 0502da1ade9d887ed4ee1a4b42ba01a5e78c8e6f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kristian=20H=C3=B8gsberg?= <krh@bitplanet.net>
Date: Thu, 18 Aug 2011 08:46:02 -0400
Subject: [PATCH] glx: Don't flush twice if we fallback to dri2CopySubBuffer

The flush extensions flush call indicates end of frame and should only
be called once per frame.  However, in the dri2SwapBuffer fallback
path, we call flush and then call dri2CopySubBuffer, which also calls
flush.  Refactor the code to only call flush once.
(cherry picked from commit 4a7667b96b7bd7cdffbe929182c15935b74facd2)
---
 src/glx/dri2_glx.c | 21 ++++++++++-----------
 1 file changed, 10 insertions(+), 11 deletions(-)

diff --git a/src/glx/dri2_glx.c b/src/glx/dri2_glx.c
index 80e4da30beb..f093f0f31ad 100644
--- a/src/glx/dri2_glx.c
+++ b/src/glx/dri2_glx.c
@@ -539,6 +539,11 @@ dri2SwapBuffers(__GLXDRIdrawable *pdraw, int64_t target_msc, int64_t divisor,
 	(struct dri2_display *)dpyPriv->dri2Display;
     CARD64 ret = 0;
 
+    /* Old servers can't handle swapbuffers */
+    if (!pdp->swapAvailable) {
+       dri2CopySubBuffer(pdraw, 0, 0, priv->width, priv->height);
+    } else {
+#ifdef X_DRI2SwapBuffers
 #ifdef __DRI2_FLUSH
     if (psc->f) {
        struct glx_context *gc = __glXGetCurrentContext();
@@ -549,21 +554,15 @@ dri2SwapBuffers(__GLXDRIdrawable *pdraw, int64_t target_msc, int64_t divisor,
     }
 #endif
 
+       DRI2SwapBuffers(psc->base.dpy, pdraw->xDrawable,
+		       target_msc, divisor, remainder, &ret);
+#endif
+    }
+
     /* Old servers don't send invalidate events */
     if (!pdp->invalidateAvailable)
        dri2InvalidateBuffers(dpyPriv->dpy, pdraw->xDrawable);
 
-    /* Old servers can't handle swapbuffers */
-    if (!pdp->swapAvailable) {
-       dri2CopySubBuffer(pdraw, 0, 0, priv->width, priv->height);
-       return 0;
-    }
-
-#ifdef X_DRI2SwapBuffers
-    DRI2SwapBuffers(psc->base.dpy, pdraw->xDrawable, target_msc, divisor,
-		    remainder, &ret);
-#endif
-
     return ret;
 }