ui freeze workaround: reenable triple buffering mode

we're seeing UI freezes when window updates and
composition are separated. for now we workaround this
by always doing a composition after window updates on
vsync. triple buffering is reenabled for performance.

Change-Id: I693d705000b7452489bb0b4918fbeadb9879315c

Author: pixelflinger

services/surfaceflinger/Android.mk

@@ -32,6 +32,7 @@ ifeq ($(TARGET_BOARD_PLATFORM), omap3)
 endif
 ifeq ($(TARGET_BOARD_PLATFORM), omap4)
 	LOCAL_CFLAGS += -DHAS_CONTEXT_PRIORITY
+	LOCAL_CFLAGS += -DUSE_TRIPLE_BUFFERING
 endif
 ifeq ($(TARGET_BOARD_PLATFORM), s5pc110)
 	LOCAL_CFLAGS += -DHAS_CONTEXT_PRIORITY -DNEVER_DEFAULT_TO_ASYNC_MODE

services/surfaceflinger/Layer.cpp

@@ -98,7 +98,12 @@ void Layer::onFirstRef()
     mSurfaceTexture = new SurfaceTextureLayer(mTextureName, this);
     mSurfaceTexture->setFrameAvailableListener(new FrameQueuedListener(this));
     mSurfaceTexture->setSynchronousMode(true);
+#ifdef USE_TRIPLE_BUFFERING
+#warning "using triple buffering"
+    mSurfaceTexture->setBufferCountServer(3);
+#else
     mSurfaceTexture->setBufferCountServer(2);
+#endif
 }
 
 Layer::~Layer()

services/surfaceflinger/MessageQueue.cpp

@@ -133,7 +133,8 @@ status_t MessageQueue::postMessage(
 }
 
 void MessageQueue::invalidate() {
-    mHandler->signalInvalidate();
+//    mHandler->signalInvalidate();
+    mEvents->requestNextVsync();
 }
 
 void MessageQueue::refresh() {

services/surfaceflinger/SurfaceFlinger.cpp

@@ -403,7 +403,8 @@ bool SurfaceFlinger::threadLoop()
 void SurfaceFlinger::onMessageReceived(int32_t what)
 {
     switch (what) {
-        case MessageQueue::INVALIDATE: {
+        case MessageQueue::REFRESH: {
+//        case MessageQueue::INVALIDATE: {
             // check for transactions
             if (CC_UNLIKELY(mConsoleSignals)) {
                 handleConsoleEvents();
@@ -419,19 +420,25 @@ void SurfaceFlinger::onMessageReceived(int32_t what)
             // post surfaces (if needed)
             handlePageFlip();
 
-            signalRefresh();
-        } break;
+//            signalRefresh();
+//
+//        } break;
+//
+//        case MessageQueue::REFRESH: {
 
-        case MessageQueue::REFRESH: {
-            // NOTE: it is mandatory to call hw.compositionComplete()
-            // after handleRefresh()
-            const DisplayHardware& hw(graphicPlane(0).displayHardware());
             handleRefresh();
 
+            const DisplayHardware& hw(graphicPlane(0).displayHardware());
+
+//            if (mDirtyRegion.isEmpty()) {
+//                return;
+//            }
+
             if (CC_UNLIKELY(mHwWorkListDirty)) {
                 // build the h/w work list
                 handleWorkList();
             }
+
             if (CC_LIKELY(hw.canDraw())) {
                 // repaint the framebuffer (if needed)
                 handleRepaint();