Bugzilla #4616:

- Merge various fb/ bits of COMPOSITE support from xserver, which weren't
    necessary before due to cw hiding the issues. Fixes offset calculations
    for a number of operations, and may pull some fixes that cairo has
    wanted for XAA as well.
- Add a new call, miDisableCompositeWrapper(), which a DDX can call to keep
    cw from getting initialized from the damage code. While it would be
    cleaner to have each DDX initialize it if it needs it, we don't have
    control over all of them (e.g. nvidia).
- Use the miDisableCompositeWrapper() to keep cw from getting set up for
    screens using EXA, because EXA is already aware of composite. Avoiding
    cw improved performance 0-35% on operations tested by ajax in x11perf.

2 files changed, 15 insertions, 0 deletions

diff --git a/miext/cw/cw.c b/miext/cw/cw.c
index 2b8010f50..4ebf8ab8a 100644
--- a/miext/cw/cw.c
+++ b/miext/cw/cw.c
@@ -48,6 +48,7 @@ int cwWindowIndex;
 #ifdef RENDER
 int cwPictureIndex;
 #endif
+static Bool cwDisabled[MAXSCREENS];
 static unsigned long cwGeneration = 0;
 extern GCOps cwGCOps;
 
@@ -617,6 +618,9 @@ miInitializeCompositeWrapper(ScreenPtr pScreen)
 {
     cwScreenPtr pScreenPriv;
 
+    if (cwDisabled[pScreen->myNum])
+	return;
+
     if (cwGeneration != serverGeneration)
     {
 	cwScreenIndex = AllocateScreenPrivateIndex();
@@ -660,6 +664,12 @@ miInitializeCompositeWrapper(ScreenPtr pScreen)
 #endif
 }
 
+void
+miDisableCompositeWrapper(ScreenPtr pScreen)
+{
+    cwDisabled[pScreen->myNum] = TRUE;
+}
+
 static Bool
 cwCloseScreen (int i, ScreenPtr pScreen)
 {
diff --git a/miext/cw/cw.h b/miext/cw/cw.h
index 1f8c400e2..67ce9cd31 100644
--- a/miext/cw/cw.h
+++ b/miext/cw/cw.h
@@ -164,5 +164,10 @@ void
 cwFiniRender (ScreenPtr pScreen);
 
 /* cw.c */
+
 void
 miInitializeCompositeWrapper(ScreenPtr pScreen);
+
+/* Must be called before miInitializeCompositeWrapper */
+void
+miDisableCompositeWrapper(ScreenPtr pScreen);