Bugzilla #4226: Change the pixmap migration strategy for the CopyNtoN case.

    Now, if either source or dest were in framebuffer, try to get both
    there, but prefer system memory for both otherwise. Required making
    exaasync.c go through the try-acceleration path. This significantly
    improves window resizing under composite, because previously the
    pattern of creating a new pixmap and copying default contents from the
    screen caused a fallback every time due to the new destination pixmap
    being in system memory.

5 files changed, 49 insertions, 17 deletions

diff --git a/exa/exa.c b/exa/exa.c
index 77d97dd96..7937f3856 100644
--- a/exa/exa.c
+++ b/exa/exa.c
@@ -605,12 +605,21 @@ exaCopyNtoN (DrawablePtr    pSrcDrawable,
     int	    dst_off_x, dst_off_y;
     STRACE;
 
-    /* Migrate pixmaps to same place as destination */
-    if (pSrcDrawable->type == DRAWABLE_PIXMAP) {
-	if (exaDrawableIsOffscreen (pDstDrawable))
+    /* If either drawable is already in framebuffer, try to get both of them
+     * there.  Otherwise, be happy with where they are.
+     */
+    if (exaDrawableIsOffscreen(pDstDrawable) ||
+	exaDrawableIsOffscreen(pSrcDrawable))
+    {
+	if (pSrcDrawable->type == DRAWABLE_PIXMAP)
 	    exaPixmapUseScreen ((PixmapPtr) pSrcDrawable);
-	else
+	if (pDstDrawable->type == DRAWABLE_PIXMAP)
+	    exaPixmapUseScreen ((PixmapPtr) pDstDrawable);
+    } else {
+	if (pSrcDrawable->type == DRAWABLE_PIXMAP)
 	    exaPixmapUseMemory ((PixmapPtr) pSrcDrawable);
+	if (pDstDrawable->type == DRAWABLE_PIXMAP)
+	    exaPixmapUseMemory ((PixmapPtr) pDstDrawable);
     }
 
     if ((pSrcPixmap = exaGetOffscreenPixmap (pSrcDrawable, &src_off_x, &src_off_y)) &&
@@ -645,7 +654,7 @@ exaCopyNtoN (DrawablePtr    pSrcDrawable,
     exaDrawableDirty (pDstDrawable);
 }
 
-static RegionPtr
+RegionPtr
 exaCopyArea(DrawablePtr pSrcDrawable, DrawablePtr pDstDrawable, GCPtr pGC,
 	    int srcx, int srcy, int width, int height, int dstx, int dsty)
 {
diff --git a/exa/exa_accel.c b/exa/exa_accel.c
index 77d97dd96..7937f3856 100644
--- a/exa/exa_accel.c
+++ b/exa/exa_accel.c
@@ -605,12 +605,21 @@ exaCopyNtoN (DrawablePtr    pSrcDrawable,
     int	    dst_off_x, dst_off_y;
     STRACE;
 
-    /* Migrate pixmaps to same place as destination */
-    if (pSrcDrawable->type == DRAWABLE_PIXMAP) {
-	if (exaDrawableIsOffscreen (pDstDrawable))
+    /* If either drawable is already in framebuffer, try to get both of them
+     * there.  Otherwise, be happy with where they are.
+     */
+    if (exaDrawableIsOffscreen(pDstDrawable) ||
+	exaDrawableIsOffscreen(pSrcDrawable))
+    {
+	if (pSrcDrawable->type == DRAWABLE_PIXMAP)
 	    exaPixmapUseScreen ((PixmapPtr) pSrcDrawable);
-	else
+	if (pDstDrawable->type == DRAWABLE_PIXMAP)
+	    exaPixmapUseScreen ((PixmapPtr) pDstDrawable);
+    } else {
+	if (pSrcDrawable->type == DRAWABLE_PIXMAP)
 	    exaPixmapUseMemory ((PixmapPtr) pSrcDrawable);
+	if (pDstDrawable->type == DRAWABLE_PIXMAP)
+	    exaPixmapUseMemory ((PixmapPtr) pDstDrawable);
     }
 
     if ((pSrcPixmap = exaGetOffscreenPixmap (pSrcDrawable, &src_off_x, &src_off_y)) &&
@@ -645,7 +654,7 @@ exaCopyNtoN (DrawablePtr    pSrcDrawable,
     exaDrawableDirty (pDstDrawable);
 }
 
-static RegionPtr
+RegionPtr
 exaCopyArea(DrawablePtr pSrcDrawable, DrawablePtr pDstDrawable, GCPtr pGC,
 	    int srcx, int srcy, int width, int height, int dstx, int dsty)
 {
diff --git a/exa/exa_migration.c b/exa/exa_migration.c
index 77d97dd96..7937f3856 100644
--- a/exa/exa_migration.c
+++ b/exa/exa_migration.c
@@ -605,12 +605,21 @@ exaCopyNtoN (DrawablePtr    pSrcDrawable,
     int	    dst_off_x, dst_off_y;
     STRACE;
 
-    /* Migrate pixmaps to same place as destination */
-    if (pSrcDrawable->type == DRAWABLE_PIXMAP) {
-	if (exaDrawableIsOffscreen (pDstDrawable))
+    /* If either drawable is already in framebuffer, try to get both of them
+     * there.  Otherwise, be happy with where they are.
+     */
+    if (exaDrawableIsOffscreen(pDstDrawable) ||
+	exaDrawableIsOffscreen(pSrcDrawable))
+    {
+	if (pSrcDrawable->type == DRAWABLE_PIXMAP)
 	    exaPixmapUseScreen ((PixmapPtr) pSrcDrawable);
-	else
+	if (pDstDrawable->type == DRAWABLE_PIXMAP)
+	    exaPixmapUseScreen ((PixmapPtr) pDstDrawable);
+    } else {
+	if (pSrcDrawable->type == DRAWABLE_PIXMAP)
 	    exaPixmapUseMemory ((PixmapPtr) pSrcDrawable);
+	if (pDstDrawable->type == DRAWABLE_PIXMAP)
+	    exaPixmapUseMemory ((PixmapPtr) pDstDrawable);
     }
 
     if ((pSrcPixmap = exaGetOffscreenPixmap (pSrcDrawable, &src_off_x, &src_off_y)) &&
@@ -645,7 +654,7 @@ exaCopyNtoN (DrawablePtr    pSrcDrawable,
     exaDrawableDirty (pDstDrawable);
 }
 
-static RegionPtr
+RegionPtr
 exaCopyArea(DrawablePtr pSrcDrawable, DrawablePtr pDstDrawable, GCPtr pGC,
 	    int srcx, int srcy, int width, int height, int dstx, int dsty)
 {
diff --git a/exa/exa_priv.h b/exa/exa_priv.h
index 724796306..3d0904375 100644
--- a/exa/exa_priv.h
+++ b/exa/exa_priv.h
@@ -261,6 +261,10 @@ exaGetOffscreenPixmap (DrawablePtr pDrawable, int *xp, int *yp);
 void
 exaMoveInPixmap (PixmapPtr pPixmap);
 
+RegionPtr
+exaCopyArea(DrawablePtr pSrcDrawable, DrawablePtr pDstDrawable, GCPtr pGC,
+	    int srcx, int srcy, int width, int height, int dstx, int dsty);
+
 void
 exaCopyNtoN (DrawablePtr    pSrcDrawable,
 	     DrawablePtr    pDstDrawable,
diff --git a/exa/exa_unaccel.c b/exa/exa_unaccel.c
index 9925f354f..c0927751b 100644
--- a/exa/exa_unaccel.c
+++ b/exa/exa_unaccel.c
@@ -280,13 +280,14 @@ ExaCheckComposite (CARD8      op,
 }
 
 /*
- * Only need to stall for copyarea/copyplane
+ * Only need to stall for CopyArea/CopyPlane, but we want to have the chance to
+ * do migration for CopyArea.
  */
 const GCOps exaAsyncPixmapGCOps = {
     fbFillSpans,
     fbSetSpans,
     fbPutImage,
-    ExaCheckCopyArea,
+    exaCopyArea,
     ExaCheckCopyPlane,
     fbPolyPoint,
     fbPolyLine,