1 files changed, 41 insertions, 17 deletions

diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index c469627..b8b6472 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -829,30 +829,39 @@ void SurfaceFlinger::eventControl(int disp, int event, int enabled) {
 void SurfaceFlinger::onMessageReceived(int32_t what) {
     ATRACE_CALL();
     switch (what) {
-    case MessageQueue::TRANSACTION:
-        handleMessageTransaction();
-        break;
-    case MessageQueue::INVALIDATE:
-        handleMessageTransaction();
-        handleMessageInvalidate();
-        signalRefresh();
-        break;
-    case MessageQueue::REFRESH:
-        handleMessageRefresh();
-        break;
+        case MessageQueue::TRANSACTION: {
+            handleMessageTransaction();
+            break;
+        }
+        case MessageQueue::INVALIDATE: {
+            bool refreshNeeded = handleMessageTransaction();
+            refreshNeeded |= handleMessageInvalidate();
+            if (refreshNeeded) {
+                // Signal a refresh if a transaction modified the window state or if
+                // a new buffer was latched
+                signalRefresh();
+            }
+            break;
+        }
+        case MessageQueue::REFRESH: {
+            handleMessageRefresh();
+            break;
+        }
     }
 }
 
-void SurfaceFlinger::handleMessageTransaction() {
+bool SurfaceFlinger::handleMessageTransaction() {
     uint32_t transactionFlags = peekTransactionFlags(eTransactionMask);
     if (transactionFlags) {
         handleTransaction(transactionFlags);
+        return true;
     }
+    return false;
 }
 
-void SurfaceFlinger::handleMessageInvalidate() {
+bool SurfaceFlinger::handleMessageInvalidate() {
     ATRACE_CALL();
-    handlePageFlip();
+    return handlePageFlip();
 }
 
 void SurfaceFlinger::handleMessageRefresh() {
@@ -1685,12 +1694,13 @@ void SurfaceFlinger::invalidateLayerStack(uint32_t layerStack,
     }
 }
 
-void SurfaceFlinger::handlePageFlip()
+bool SurfaceFlinger::handlePageFlip()
 {
     Region dirtyRegion;
 
     bool visibleRegions = false;
     const LayerVector& layers(mDrawingState.layersSortedByZ);
+    bool frameQueued = false;
 
     // Store the set of layers that need updates. This set must not change as
     // buffers are being latched, as this could result in a deadlock.
@@ -1704,8 +1714,12 @@ void SurfaceFlinger::handlePageFlip()
     Vector<Layer*> layersWithQueuedFrames;
     for (size_t i = 0, count = layers.size(); i<count ; i++) {
         const sp<Layer>& layer(layers[i]);
-        if (layer->hasQueuedFrame())
-            layersWithQueuedFrames.push_back(layer.get());
+        if (layer->hasQueuedFrame()) {
+            frameQueued = true;
+            if (layer->shouldPresentNow(mPrimaryDispSync)) {
+                layersWithQueuedFrames.push_back(layer.get());
+            }
+        }
     }
     for (size_t i = 0, count = layersWithQueuedFrames.size() ; i<count ; i++) {
         Layer* layer = layersWithQueuedFrames[i];
@@ -1715,6 +1729,16 @@ void SurfaceFlinger::handlePageFlip()
     }
 
     mVisibleRegionsDirty |= visibleRegions;
+
+    // If we will need to wake up at some time in the future to deal with a
+    // queued frame that shouldn't be displayed during this vsync period, wake
+    // up during the next vsync period to check again.
+    if (frameQueued && layersWithQueuedFrames.empty()) {
+        signalLayerUpdate();
+    }
+
+    // Only continue with the refresh if there is actually new work to do
+    return !layersWithQueuedFrames.empty();
 }
 
 void SurfaceFlinger::invalidateHwcGeometry()