From 4f6e3b0f378d7306dbd8c00ef9a7df81e24e5769 Mon Sep 17 00:00:00 2001
From: Pauli Nieminen <ext-pauli.nieminen@nokia.com>
Date: Thu, 30 Dec 2010 19:19:39 +0200
Subject: [PATCH] mi: Register sprite damage handler only when required

There is no need to have damage handler registered when there isn't any
pointer in the screen. This avoids some overhead from damage handling
which takes tens of microseconds on arm.

Signed-off-by: Pauli Nieminen <ext-pauli.nieminen@nokia.com>
Reviewed-by: Daniel Stone <daniel@fooishbar.org>
---
 mi/misprite.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/mi/misprite.c b/mi/misprite.c
index a269705b2..1a76d2001 100644
--- a/mi/misprite.c
+++ b/mi/misprite.c
@@ -96,6 +96,7 @@ typedef struct {
     VisualPtr	    pVisual;
     DamagePtr	    pDamage;		/* damage tracking structure */
     Bool            damageRegistered;
+    int             numberOfCursors;
 } miSpriteScreenRec, *miSpriteScreenPtr;
 
 #define SOURCE_COLOR	0
@@ -345,6 +346,7 @@ miSpriteInitialize (ScreenPtr               pScreen,
     pScreenPriv->colors[MASK_COLOR].green = 0;
     pScreenPriv->colors[MASK_COLOR].blue = 0;
     pScreenPriv->damageRegistered = 0;
+    pScreenPriv->numberOfCursors = 0;
 
     dixSetPrivate(&pScreen->devPrivates, miSpriteScreenKey, pScreenPriv);
 
@@ -772,21 +774,29 @@ static void
 miSpriteSetCursor (DeviceIntPtr pDev, ScreenPtr pScreen,
                    CursorPtr pCursor, int x, int y)
 {
-    miCursorInfoPtr pPointer;
+    miCursorInfoPtr     pPointer;
+    miSpriteScreenPtr   pScreenPriv;
 
     if (!IsMaster(pDev) && !pDev->u.master)
         return;
 
     pPointer = MISPRITE(pDev);
+    pScreenPriv = GetSpriteScreen(pScreen);
 
     if (!pCursor)
     {
+	if (pPointer->shouldBeUp)
+	    --pScreenPriv->numberOfCursors;
     	pPointer->shouldBeUp = FALSE;
     	if (pPointer->isUp)
 	    miSpriteRemoveCursor (pDev, pScreen);
+	if (pScreenPriv->numberOfCursors == 0)
+	    miSpriteDisableDamage(pScreen, pScreenPriv);
 	pPointer->pCursor = 0;
 	return;
     }
+    if (!pPointer->shouldBeUp)
+	pScreenPriv->numberOfCursors++;
     pPointer->shouldBeUp = TRUE;
     if (pPointer->x == x &&
 	pPointer->y == y &&