From 13ac3deedb532b39f41dcd45d70f9eb4a85c1f58 Mon Sep 17 00:00:00 2001
From: Pauli Nieminen <ext-pauli.nieminen@nokia.com>
Date: Thu, 30 Dec 2010 19:19:40 +0200
Subject: [PATCH] mi: Only register sprite block handler when needed

miSpriteBlockHandler takes about 10us in arm each time BlockHandlers are
called. To eliminate that overhead from xserver side only register the
BlockHandler when there actually is any cursor down.

Signed-off-by: Pauli Nieminen <ext-pauli.nieminen@nokia.com>
Reviewed-by: Daniel Stone <daniel@fooishbar.org>
---
 mi/misprite.c | 35 +++++++++++++++++++++++++----------
 1 file changed, 25 insertions(+), 10 deletions(-)

diff --git a/mi/misprite.c b/mi/misprite.c
index 1a76d2001..c25c093f2 100644
--- a/mi/misprite.c
+++ b/mi/misprite.c
@@ -255,6 +255,15 @@ static void miSpriteSaveUnderCursor(DeviceIntPtr pDev,
 static void miSpriteRestoreCursor(DeviceIntPtr pDev,
                                  ScreenPtr pScreen);
 
+static void
+miSpriteRegisterBlockHandler(ScreenPtr pScreen, miSpriteScreenPtr pScreenPriv)
+{
+    if (!pScreenPriv->BlockHandler) {
+        pScreenPriv->BlockHandler = pScreen->BlockHandler;
+        pScreen->BlockHandler = miSpriteBlockHandler;
+    }
+}
+
 static void
 miSpriteReportDamage (DamagePtr pDamage, RegionPtr pRegion, void *closure)
 {
@@ -332,7 +341,7 @@ miSpriteInitialize (ScreenPtr               pScreen,
     pScreenPriv->InstallColormap = pScreen->InstallColormap;
     pScreenPriv->StoreColors = pScreen->StoreColors;
 
-    pScreenPriv->BlockHandler = pScreen->BlockHandler;
+    pScreenPriv->BlockHandler = NULL;
 
     pScreenPriv->DeviceCursorInitialize = pScreen->DeviceCursorInitialize;
     pScreenPriv->DeviceCursorCleanup = pScreen->DeviceCursorCleanup;
@@ -359,8 +368,6 @@ miSpriteInitialize (ScreenPtr               pScreen,
     pScreen->InstallColormap = miSpriteInstallColormap;
     pScreen->StoreColors = miSpriteStoreColors;
 
-    pScreen->BlockHandler = miSpriteBlockHandler;
-
     return TRUE;
 }
 
@@ -382,7 +389,6 @@ miSpriteCloseScreen (int i, ScreenPtr pScreen)
     pScreen->GetImage = pScreenPriv->GetImage;
     pScreen->GetSpans = pScreenPriv->GetSpans;
     pScreen->SourceValidate = pScreenPriv->SourceValidate;
-    pScreen->BlockHandler = pScreenPriv->BlockHandler;
     pScreen->InstallColormap = pScreenPriv->InstallColormap;
     pScreen->StoreColors = pScreenPriv->StoreColors;
 
@@ -555,12 +561,7 @@ miSpriteBlockHandler (int i, pointer blockData, pointer pTimeout,
     miSpriteScreenPtr	pPriv = GetSpriteScreen(pScreen);
     DeviceIntPtr            pDev;
     miCursorInfoPtr         pCursorInfo;
-
-    SCREEN_PROLOGUE(pPriv, pScreen, BlockHandler);
-
-    (*pScreen->BlockHandler) (i, blockData, pTimeout, pReadmask);
-
-    SCREEN_EPILOGUE(pPriv, pScreen, BlockHandler);
+    Bool                WorkToDo = FALSE;
 
     for(pDev = inputInfo.devices; pDev; pDev = pDev->next)
     {
@@ -587,9 +588,20 @@ miSpriteBlockHandler (int i, pointer blockData, pointer pTimeout,
             {
                 SPRITE_DEBUG (("BlockHandler restore\n"));
                 miSpriteRestoreCursor (pDev, pScreen);
+                if (!pCursorInfo->isUp)
+                    WorkToDo = TRUE;
             }
         }
     }
+
+    SCREEN_PROLOGUE(pPriv, pScreen, BlockHandler);
+
+    (*pScreen->BlockHandler) (i, blockData, pTimeout, pReadmask);
+
+    if (WorkToDo)
+        SCREEN_EPILOGUE(pPriv, pScreen, BlockHandler);
+    else
+        pPriv->BlockHandler = NULL;
 }
 
 static void
@@ -798,6 +810,8 @@ miSpriteSetCursor (DeviceIntPtr pDev, ScreenPtr pScreen,
     if (!pPointer->shouldBeUp)
 	pScreenPriv->numberOfCursors++;
     pPointer->shouldBeUp = TRUE;
+    if (!pPointer->isUp)
+	miSpriteRegisterBlockHandler(pScreen, pScreenPriv);
     if (pPointer->x == x &&
 	pPointer->y == y &&
 	pPointer->pCursor == pCursor &&
@@ -898,6 +912,7 @@ miSpriteRemoveCursor (DeviceIntPtr pDev, ScreenPtr pScreen)
     pCursorInfo = MISPRITE(pDev);
 
     miSpriteIsDown(pCursorInfo);
+    miSpriteRegisterBlockHandler(pScreen, pScreenPriv);
     pCursorInfo->pCacheWin = NullWindow;
     miSpriteDisableDamage(pScreen, pScreenPriv);
     if (!miDCRestoreUnderCursor(pDev,