[PATCH] uxa_glamor_dri: Use exchange buffer in glamor fixup.

[zhigang.gong@linux.intel.com]

From: Zhigang Gong <zhigang.gong@linux.intel.com>

The previous implementation is to create a new textured
pixmap based on the newly created pixmap's buffer object.

This is not efficient, as we already created it when we
call CreatePixmap. We can just exchange the underlying
texture/image buffers by calling intel_glamor_exchange_buffers().

And this commit seems also fix a weird rendering problem
when working with compiz/mutter.

Signed-off-by: Zhigang Gong <zhigang.gong@linux.intel.com>
---
 src/intel_dri.c |   29 ++++++++++-------------------
 1 files changed, 10 insertions(+), 19 deletions(-)

diff --git a/src/intel_dri.c b/src/intel_dri.c
index d027a64..c168b78 100644
--- a/src/intel_dri.c
+++ b/src/intel_dri.c
@@ -110,6 +110,7 @@ static PixmapPtr fixup_glamor(DrawablePtr drawable, PixmapPtr pixmap)
 {
 	ScreenPtr screen = drawable->pScreen;
 	ScrnInfoPtr scrn = xf86ScreenToScrn(screen);
+	intel_screen_private *intel = intel_get_screen_private(scrn);
 	PixmapPtr old = get_drawable_pixmap(drawable);
 	struct intel_pixmap *priv = intel_get_pixmap_private(pixmap);
 	GCPtr gc;
@@ -139,28 +140,20 @@ static PixmapPtr fixup_glamor(DrawablePtr drawable, PixmapPtr pixmap)
 	}
 
 	intel_set_pixmap_private(pixmap, NULL);
-	screen->DestroyPixmap(pixmap);
 
+	/* Exchange the underlying texture/image. */
+	intel_glamor_exchange_buffers(intel, old, pixmap);
 	/* And redirect the pixmap to the new bo (for 3D). */
 	intel_set_pixmap_private(old, priv);
 	old->refcnt++;
 
-	/* This creating should not fail, as we already created its
-	 * successfully. But if it happens, we put a warning indicator
-	 * here, and the old pixmap will still be a glamor pixmap, and
-	 * latter the pixmap_flink will get a 0 name, then the X server
-	 * will pass a BadAlloc to the client.*/
-	if (!intel_glamor_create_textured_pixmap(old))
-		xf86DrvMsg(scrn->scrnIndex, X_WARNING,
-			   "Failed to get DRI drawable for glamor pixmap.\n");
-
 	screen->ModifyPixmapHeader(old,
 				   drawable->width,
 				   drawable->height,
 				   0, 0,
 				   priv->stride,
 				   NULL);
-
+	screen->DestroyPixmap(pixmap);
 	intel_get_screen_private(xf86ScreenToScrn(screen))->needs_flush = TRUE;
 	return old;
 }
@@ -194,10 +187,9 @@ I830DRI2CreateBuffers(DrawablePtr drawable, unsigned int *attachments,
 		if (attachments[i] == DRI2BufferFrontLeft) {
 			pixmap = get_front_buffer(drawable);
 
-			if (pixmap && intel_get_pixmap_private(pixmap) == NULL) {
+			if (pixmap == NULL) {
+				drawable = &(get_drawable_pixmap(drawable)->drawable);
 				is_glamor_pixmap = TRUE;
-				drawable = &pixmap->drawable;
-				pixmap = NULL;
 			}
 		} else if (attachments[i] == DRI2BufferStencil && pDepthPixmap) {
 			pixmap = pDepthPixmap;
@@ -237,7 +229,7 @@ I830DRI2CreateBuffers(DrawablePtr drawable, unsigned int *attachments,
 				goto unwind;
 			}
 
-			if (attachment == DRI2BufferFrontLeft)
+			if (attachment == DRI2BufferFrontLeft && is_glamor_pixmap)
 				pixmap = fixup_glamor(drawable, pixmap);
 		}
 
@@ -314,10 +306,9 @@ I830DRI2CreateBuffer(DrawablePtr drawable, unsigned int attachment,
 	if (attachment == DRI2BufferFrontLeft) {
 		pixmap = get_front_buffer(drawable);
 
-		if (pixmap && intel_get_pixmap_private(pixmap) == NULL) {
+		if (pixmap == NULL) {
+			drawable = &(get_drawable_pixmap(drawable)->drawable);
 			is_glamor_pixmap = TRUE;
-			drawable = &pixmap->drawable;
-			pixmap = NULL;
 		}
 	}
 
@@ -391,7 +382,7 @@ I830DRI2CreateBuffer(DrawablePtr drawable, unsigned int attachment,
 			free(buffer);
 			return NULL;
 		}
-		if (attachment == DRI2BufferFrontLeft)
+		if (attachment == DRI2BufferFrontLeft && is_glamor_pixmap)
 			pixmap = fixup_glamor(drawable, pixmap);
 	}
 
-- 
1.7.4.4