11 files changed, 557 insertions, 206 deletions

diff --git a/core/java/android/view/InputEventReceiver.java b/core/java/android/view/InputEventReceiver.java
index 764d8dc..6a457ec 100644
--- a/core/java/android/view/InputEventReceiver.java
+++ b/core/java/android/view/InputEventReceiver.java
@@ -21,6 +21,7 @@ import dalvik.system.CloseGuard;
 import android.os.Looper;
 import android.os.MessageQueue;
 import android.util.Log;
+import android.util.SparseIntArray;
 
 /**
  * Provides a low-level mechanism for an application to receive input events.
@@ -38,13 +39,14 @@ public abstract class InputEventReceiver {
     private InputChannel mInputChannel;
     private MessageQueue mMessageQueue;
 
-    // The sequence number of the event that is in progress.
-    private int mEventSequenceNumberInProgress = -1;
+    // Map from InputEvent sequence numbers to dispatcher sequence numbers.
+    private final SparseIntArray mSeqMap = new SparseIntArray();
 
     private static native int nativeInit(InputEventReceiver receiver,
             InputChannel inputChannel, MessageQueue messageQueue);
     private static native void nativeDispose(int receiverPtr);
-    private static native void nativeFinishInputEvent(int receiverPtr, boolean handled);
+    private static native void nativeFinishInputEvent(int receiverPtr, int seq, boolean handled);
+    private static native void nativeConsumeBatchedInputEvents(int receiverPtr);
 
     /**
      * Creates an input event receiver bound to the specified input channel.
@@ -104,12 +106,25 @@ public abstract class InputEventReceiver {
     }
 
     /**
+     * Called when a batched input event is pending.
+     *
+     * The batched input event will continue to accumulate additional movement
+     * samples until the recipient calls {@link #consumeBatchedInputEvents} or
+     * an event is received that ends the batch and causes it to be consumed
+     * immediately (such as a pointer up event).
+     */
+    public void onBatchedInputEventPending() {
+        consumeBatchedInputEvents();
+    }
+
+    /**
      * Finishes an input event and indicates whether it was handled.
+     * Must be called on the same Looper thread to which the receiver is attached.
      *
      * @param event The input event that was finished.
      * @param handled True if the event was handled.
      */
-    public void finishInputEvent(InputEvent event, boolean handled) {
+    public final void finishInputEvent(InputEvent event, boolean handled) {
         if (event == null) {
             throw new IllegalArgumentException("event must not be null");
         }
@@ -117,23 +132,47 @@ public abstract class InputEventReceiver {
             Log.w(TAG, "Attempted to finish an input event but the input event "
                     + "receiver has already been disposed.");
         } else {
-            if (event.getSequenceNumber() != mEventSequenceNumberInProgress) {
+            int index = mSeqMap.indexOfKey(event.getSequenceNumber());
+            if (index < 0) {
                 Log.w(TAG, "Attempted to finish an input event that is not in progress.");
             } else {
-                mEventSequenceNumberInProgress = -1;
-                nativeFinishInputEvent(mReceiverPtr, handled);
+                int seq = mSeqMap.valueAt(index);
+                mSeqMap.removeAt(index);
+                nativeFinishInputEvent(mReceiverPtr, seq, handled);
             }
         }
         event.recycleIfNeededAfterDispatch();
     }
 
+    /**
+     * Consumes all pending batched input events.
+     * Must be called on the same Looper thread to which the receiver is attached.
+     *
+     * This method forces all batched input events to be delivered immediately.
+     * Should be called just before animating or drawing a new frame in the UI.
+     */
+    public final void consumeBatchedInputEvents() {
+        if (mReceiverPtr == 0) {
+            Log.w(TAG, "Attempted to consume batched input events but the input event "
+                    + "receiver has already been disposed.");
+        } else {
+            nativeConsumeBatchedInputEvents(mReceiverPtr);
+        }
+    }
+
     // Called from native code.
     @SuppressWarnings("unused")
-    private void dispatchInputEvent(InputEvent event) {
-        mEventSequenceNumberInProgress = event.getSequenceNumber();
+    private void dispatchInputEvent(int seq, InputEvent event) {
+        mSeqMap.put(event.getSequenceNumber(), seq);
         onInputEvent(event);
     }
 
+    // Called from native code.
+    @SuppressWarnings("unused")
+    private void dispatchBatchedInputEventPending() {
+        onBatchedInputEventPending();
+    }
+
     public static interface Factory {
         public InputEventReceiver createInputEventReceiver(
                 InputChannel inputChannel, Looper looper);
diff --git a/core/java/android/view/ViewRootImpl.java b/core/java/android/view/ViewRootImpl.java
index 940d4c6..1930a5e 100644
--- a/core/java/android/view/ViewRootImpl.java
+++ b/core/java/android/view/ViewRootImpl.java
@@ -851,6 +851,11 @@ public final class ViewRootImpl extends Handler implements ViewParent,
 
     @Override
     public void onDraw() {
+        if (mInputEventReceiver != null) {
+            mInputEventReceiver.consumeBatchedInputEvents();
+        }
+        doProcessInputEvents();
+
         if (mTraversalScheduled) {
             mTraversalScheduled = false;
             doTraversal();
@@ -891,8 +896,6 @@ public final class ViewRootImpl extends Handler implements ViewParent,
     }
 
     private void doTraversal() {
-        doProcessInputEvents();
-
         if (mProfile) {
             Debug.startMethodTracing("ViewAncestor");
         }
@@ -3929,6 +3932,11 @@ public final class ViewRootImpl extends Handler implements ViewParent,
         public void onInputEvent(InputEvent event) {
             enqueueInputEvent(event, this, 0, true);
         }
+
+        @Override
+        public void onBatchedInputEventPending() {
+            mChoreographer.scheduleDraw();
+        }
     }
     WindowInputEventReceiver mInputEventReceiver;
 
diff --git a/core/jni/android_app_NativeActivity.cpp b/core/jni/android_app_NativeActivity.cpp
index f383c5d..536681b 100644
--- a/core/jni/android_app_NativeActivity.cpp
+++ b/core/jni/android_app_NativeActivity.cpp
@@ -172,7 +172,7 @@ int32_t AInputQueue::getEvent(AInputEvent** outEvent) {
             in_flight_event inflight;
             inflight.event = kevent;
             inflight.seq = -1;
-            inflight.doFinish = false;
+            inflight.finishSeq = 0;
             mInFlightEvents.push(inflight);
         }
         if (mFinishPreDispatches.size() > 0) {
@@ -201,19 +201,21 @@ int32_t AInputQueue::getEvent(AInputEvent** outEvent) {
         }
     }
 
+    uint32_t consumerSeq;
     InputEvent* myEvent = NULL;
-    status_t res = mConsumer.consume(this, &myEvent);
+    status_t res = mConsumer.consume(this, true /*consumeBatches*/, &consumerSeq, &myEvent);
     if (res != android::OK) {
-        ALOGW("channel '%s' ~ Failed to consume input event.  status=%d",
-                mConsumer.getChannel()->getName().string(), res);
-        mConsumer.sendFinishedSignal(false);
+        if (res != android::WOULD_BLOCK) {
+            ALOGW("channel '%s' ~ Failed to consume input event.  status=%d",
+                    mConsumer.getChannel()->getName().string(), res);
+        }
         return -1;
     }
 
     in_flight_event inflight;
     inflight.event = myEvent;
     inflight.seq = -1;
-    inflight.doFinish = true;
+    inflight.finishSeq = consumerSeq;
     mInFlightEvents.push(inflight);
 
     *outEvent = myEvent;
@@ -255,8 +257,8 @@ void AInputQueue::finishEvent(AInputEvent* event, bool handled, bool didDefaultH
     for (size_t i=0; i<N; i++) {
         const in_flight_event& inflight(mInFlightEvents[i]);
         if (inflight.event == event) {
-            if (inflight.doFinish) {
-                int32_t res = mConsumer.sendFinishedSignal(handled);
+            if (inflight.finishSeq) {
+                status_t res = mConsumer.sendFinishedSignal(inflight.finishSeq, handled);
                 if (res != android::OK) {
                     ALOGW("Failed to send finished signal on channel '%s'.  status=%d",
                             mConsumer.getChannel()->getName().string(), res);
diff --git a/core/jni/android_view_InputEventReceiver.cpp b/core/jni/android_view_InputEventReceiver.cpp
index 23e1590..4b737ed 100644
--- a/core/jni/android_view_InputEventReceiver.cpp
+++ b/core/jni/android_view_InputEventReceiver.cpp
@@ -40,6 +40,7 @@ static struct {
     jclass clazz;
 
     jmethodID dispatchInputEvent;
+    jmethodID dispatchBatchedInputEventPending;
 } gInputEventReceiverClassInfo;
 
 
@@ -50,7 +51,8 @@ public:
             const sp<Looper>& looper);
 
     status_t initialize();
-    status_t finishInputEvent(bool handled);
+    status_t finishInputEvent(uint32_t seq, bool handled);
+    status_t consumeEvents(bool consumeBatches);
     static int handleReceiveCallback(int receiveFd, int events, void* data);
 
 protected:
@@ -60,8 +62,8 @@ private:
     jobject mReceiverObjGlobal;
     InputConsumer mInputConsumer;
     sp<Looper> mLooper;
-    bool mEventInProgress;
     PreallocatedInputEventFactory mInputEventFactory;
+    bool mBatchedInputEventPending;
 
     const char* getInputChannelName() {
         return mInputConsumer.getChannel()->getName().string();
@@ -72,7 +74,8 @@ private:
 NativeInputEventReceiver::NativeInputEventReceiver(JNIEnv* env,
         jobject receiverObj, const sp<InputChannel>& inputChannel, const sp<Looper>& looper) :
         mReceiverObjGlobal(env->NewGlobalRef(receiverObj)),
-        mInputConsumer(inputChannel), mLooper(looper), mEventInProgress(false) {
+        mInputConsumer(inputChannel), mLooper(looper),
+        mBatchedInputEventPending(false) {
 #if DEBUG_DISPATCH_CYCLE
     ALOGD("channel '%s' ~ Initializing input event receiver.", getInputChannelName());
 #endif
@@ -84,9 +87,6 @@ NativeInputEventReceiver::~NativeInputEventReceiver() {
 #endif
 
     mLooper->removeFd(mInputConsumer.getChannel()->getFd());
-    if (mEventInProgress) {
-        mInputConsumer.sendFinishedSignal(false); // ignoring result
-    }
 
     JNIEnv* env = AndroidRuntime::getJNIEnv();
     env->DeleteGlobalRef(mReceiverObjGlobal);
@@ -98,23 +98,17 @@ status_t NativeInputEventReceiver::initialize() {
     return OK;
 }
 
-status_t NativeInputEventReceiver::finishInputEvent(bool handled) {
-    if (mEventInProgress) {
+status_t NativeInputEventReceiver::finishInputEvent(uint32_t seq, bool handled) {
 #if DEBUG_DISPATCH_CYCLE
-        ALOGD("channel '%s' ~ Finished input event.", getInputChannelName());
+    ALOGD("channel '%s' ~ Finished input event.", getInputChannelName());
 #endif
-        mEventInProgress = false;
 
-        status_t status = mInputConsumer.sendFinishedSignal(handled);
-        if (status) {
-            ALOGW("Failed to send finished signal on channel '%s'.  status=%d",
-                    getInputChannelName(), status);
-        }
-        return status;
-    } else {
-        ALOGW("Ignoring attempt to finish input event while no event is in progress.");
-        return OK;
+    status_t status = mInputConsumer.sendFinishedSignal(seq, handled);
+    if (status) {
+        ALOGW("Failed to send finished signal on channel '%s'.  status=%d",
+                getInputChannelName(), status);
     }
+    return status;
 }
 
 int NativeInputEventReceiver::handleReceiveCallback(int receiveFd, int events, void* data) {
@@ -132,79 +126,101 @@ int NativeInputEventReceiver::handleReceiveCallback(int receiveFd, int events, v
         return 1;
     }
 
-    if (r->mEventInProgress) {
-        ALOGW("channel '%s' ~ Publisher sent spurious dispatch signal.",
-                r->getInputChannelName());
-        return 1;
-    }
+    status_t status = r->consumeEvents(false /*consumeBatches*/);
+    return status == OK || status == NO_MEMORY ? 1 : 0;
+}
 
-    InputEvent* inputEvent;
-    status_t status = r->mInputConsumer.consume(&r->mInputEventFactory, &inputEvent);
-    if (status) {
-        ALOGW("channel '%s' ~ Failed to consume input event.  status=%d",
-                r->getInputChannelName(), status);
-        r->mInputConsumer.sendFinishedSignal(false);
-        return 1;
+status_t NativeInputEventReceiver::consumeEvents(bool consumeBatches) {
+#if DEBUG_DISPATCH_CYCLE
+    ALOGD("channel '%s' ~ Consuming input events, consumeBatches=%s.", getInputChannelName(),
+            consumeBatches ? "true" : "false");
+#endif
+
+    if (consumeBatches) {
+        mBatchedInputEventPending = false;
     }
 
     JNIEnv* env = AndroidRuntime::getJNIEnv();
-    jobject inputEventObj;
-    switch (inputEvent->getType()) {
-    case AINPUT_EVENT_TYPE_KEY:
+    for (;;) {
+        uint32_t seq;
+        InputEvent* inputEvent;
+        status_t status = mInputConsumer.consume(&mInputEventFactory,
+                consumeBatches, &seq, &inputEvent);
+        if (status) {
+            if (status == WOULD_BLOCK) {
+                if (mInputConsumer.hasPendingBatch() && !mBatchedInputEventPending) {
+                    // There is a pending batch.  Come back later.
+                    mBatchedInputEventPending = true;
 #if DEBUG_DISPATCH_CYCLE
-        ALOGD("channel '%s' ~ Received key event.",
-                r->getInputChannelName());
+                    ALOGD("channel '%s' ~ Dispatching batched input event pending notification.",
+                            getInputChannelName());
 #endif
-        inputEventObj = android_view_KeyEvent_fromNative(env,
-                static_cast<KeyEvent*>(inputEvent));
-        break;
+                    env->CallVoidMethod(mReceiverObjGlobal,
+                            gInputEventReceiverClassInfo.dispatchBatchedInputEventPending);
+
+                    if (env->ExceptionCheck()) {
+                        ALOGE("channel '%s' ~ An exception occurred while dispatching that "
+                                "batched input events are pending.", getInputChannelName());
+                        LOGE_EX(env);
+                        env->ExceptionClear();
+                        mBatchedInputEventPending = false; // try again later
+                    }
+                }
+                return OK;
+            }
+            ALOGE("channel '%s' ~ Failed to consume input event.  status=%d",
+                    getInputChannelName(), status);
+            return status;
+        }
+        assert(inputEvent);
 
-    case AINPUT_EVENT_TYPE_MOTION:
+        jobject inputEventObj;
+        switch (inputEvent->getType()) {
+        case AINPUT_EVENT_TYPE_KEY:
 #if DEBUG_DISPATCH_CYCLE
-        ALOGD("channel '%s' ~ Received motion event.",
-                r->getInputChannelName());
+            ALOGD("channel '%s' ~ Received key event.", getInputChannelName());
 #endif
-        inputEventObj = android_view_MotionEvent_obtainAsCopy(env,
-                static_cast<MotionEvent*>(inputEvent));
-        break;
+            inputEventObj = android_view_KeyEvent_fromNative(env,
+                    static_cast<KeyEvent*>(inputEvent));
+            break;
 
-    default:
-        assert(false); // InputConsumer should prevent this from ever happening
-        inputEventObj = NULL;
-    }
+        case AINPUT_EVENT_TYPE_MOTION:
+#if DEBUG_DISPATCH_CYCLE
+            ALOGD("channel '%s' ~ Received motion event.", getInputChannelName());
+#endif
+            inputEventObj = android_view_MotionEvent_obtainAsCopy(env,
+                    static_cast<MotionEvent*>(inputEvent));
+            break;
 
-    if (!inputEventObj) {
-        ALOGW("channel '%s' ~ Failed to obtain event object.",
-                r->getInputChannelName());
-        r->mInputConsumer.sendFinishedSignal(false);
-        return 1;
-    }
+        default:
+            assert(false); // InputConsumer should prevent this from ever happening
+            inputEventObj = NULL;
+        }
 
-    r->mEventInProgress = true;
+        if (!inputEventObj) {
+            ALOGW("channel '%s' ~ Failed to obtain event object.", getInputChannelName());
+            mInputConsumer.sendFinishedSignal(seq, false);
+            return NO_MEMORY;
+        }
 
 #if DEBUG_DISPATCH_CYCLE
-    ALOGD("channel '%s' ~ Invoking input handler.", r->getInputChannelName());
-#endif
-    env->CallVoidMethod(r->mReceiverObjGlobal,
-            gInputEventReceiverClassInfo.dispatchInputEvent, inputEventObj);
-#if DEBUG_DISPATCH_CYCLE
-    ALOGD("channel '%s' ~ Returned from input handler.", r->getInputChannelName());
+        ALOGD("channel '%s' ~ Dispatching input event.", getInputChannelName());
 #endif
+        env->CallVoidMethod(mReceiverObjGlobal,
+                gInputEventReceiverClassInfo.dispatchInputEvent, seq, inputEventObj);
 
-    if (env->ExceptionCheck()) {
-        ALOGE("channel '%s' ~ An exception occurred while dispatching an event.",
-                r->getInputChannelName());
-        LOGE_EX(env);
-        env->ExceptionClear();
+        env->DeleteLocalRef(inputEventObj);
 
-        if (r->mEventInProgress) {
-            r->mInputConsumer.sendFinishedSignal(false);
-            r->mEventInProgress = false;
+        if (env->ExceptionCheck()) {
+            ALOGE("channel '%s' ~ An exception occurred while dispatching an event.",
+                    getInputChannelName());
+            LOGE_EX(env);
+            env->ExceptionClear();
+
+            mInputConsumer.sendFinishedSignal(seq, false);
+            return OK;
         }
     }
-
-    env->DeleteLocalRef(inputEventObj);
-    return 1;
 }
 
 
@@ -243,10 +259,11 @@ static void nativeDispose(JNIEnv* env, jclass clazz, jint receiverPtr) {
     receiver->decStrong(gInputEventReceiverClassInfo.clazz); // drop reference held by the object
 }
 
-static void nativeFinishInputEvent(JNIEnv* env, jclass clazz, jint receiverPtr, jboolean handled) {
+static void nativeFinishInputEvent(JNIEnv* env, jclass clazz, jint receiverPtr,
+        jint seq, jboolean handled) {
     sp<NativeInputEventReceiver> receiver =
             reinterpret_cast<NativeInputEventReceiver*>(receiverPtr);
-    status_t status = receiver->finishInputEvent(handled);
+    status_t status = receiver->finishInputEvent(seq, handled);
     if (status) {
         String8 message;
         message.appendFormat("Failed to finish input event.  status=%d", status);
@@ -254,17 +271,29 @@ static void nativeFinishInputEvent(JNIEnv* env, jclass clazz, jint receiverPtr,
     }
 }
 
+static void nativeConsumeBatchedInputEvents(JNIEnv* env, jclass clazz, jint receiverPtr) {
+    sp<NativeInputEventReceiver> receiver =
+            reinterpret_cast<NativeInputEventReceiver*>(receiverPtr);
+    status_t status = receiver->consumeEvents(true /*consumeBatches*/);
+    if (status) {
+        String8 message;
+        message.appendFormat("Failed to consume batched input event.  status=%d", status);
+        jniThrowRuntimeException(env, message.string());
+    }
+}
+
 
 static JNINativeMethod gMethods[] = {
     /* name, signature, funcPtr */
     { "nativeInit",
             "(Landroid/view/InputEventReceiver;Landroid/view/InputChannel;Landroid/os/MessageQueue;)I",
             (void*)nativeInit },
-    { "nativeDispose",
-            "(I)V",
+    { "nativeDispose", "(I)V",
             (void*)nativeDispose },
-    { "nativeFinishInputEvent", "(IZ)V",
-            (void*)nativeFinishInputEvent }
+    { "nativeFinishInputEvent", "(IIZ)V",
+            (void*)nativeFinishInputEvent },
+    { "nativeConsumeBatchedInputEvents", "(I)V",
+            (void*)nativeConsumeBatchedInputEvents },
 };
 
 #define FIND_CLASS(var, className) \
@@ -285,7 +314,10 @@ int register_android_view_InputEventReceiver(JNIEnv* env) {
 
     GET_METHOD_ID(gInputEventReceiverClassInfo.dispatchInputEvent,
             gInputEventReceiverClassInfo.clazz,
-            "dispatchInputEvent", "(Landroid/view/InputEvent;)V");
+            "dispatchInputEvent", "(ILandroid/view/InputEvent;)V");
+    GET_METHOD_ID(gInputEventReceiverClassInfo.dispatchBatchedInputEventPending,
+            gInputEventReceiverClassInfo.clazz,
+            "dispatchBatchedInputEventPending", "()V");
     return 0;
 }
 
diff --git a/include/android_runtime/android_app_NativeActivity.h b/include/android_runtime/android_app_NativeActivity.h
index 990143b..93fcf69 100644
--- a/include/android_runtime/android_app_NativeActivity.h
+++ b/include/android_runtime/android_app_NativeActivity.h
@@ -114,8 +114,8 @@ private:
 
     struct in_flight_event {
         android::InputEvent* event;
-        int seq;
-        bool doFinish;
+        int seq; // internal sequence number for synthetic pre-dispatch events
+        uint32_t finishSeq; // sequence number for sendFinishedSignal, or 0 if finish not required
     };
 
     struct finish_pre_dispatch {
diff --git a/include/ui/InputTransport.h b/include/ui/InputTransport.h
index f3a39c3..bdd2fb9 100644
--- a/include/ui/InputTransport.h
+++ b/include/ui/InputTransport.h
@@ -52,6 +52,7 @@ struct InputMessage {
 
     union Body {
         struct Key {
+            uint32_t seq;
             nsecs_t eventTime;
             int32_t deviceId;
             int32_t source;
@@ -69,6 +70,7 @@ struct InputMessage {
         } key;
 
         struct Motion {
+            uint32_t seq;
             nsecs_t eventTime;
             int32_t deviceId;
             int32_t source;
@@ -95,6 +97,7 @@ struct InputMessage {
         } motion;
 
         struct Finished {
+            uint32_t seq;
             bool handled;
 
             inline size_t size() const {
@@ -181,9 +184,11 @@ public:
      * Returns OK on success.
      * Returns WOULD_BLOCK if the channel is full.
      * Returns DEAD_OBJECT if the channel's peer has been closed.
+     * Returns BAD_VALUE if seq is 0.
      * Other errors probably indicate that the channel is broken.
      */
     status_t publishKeyEvent(
+            uint32_t seq,
             int32_t deviceId,
             int32_t source,
             int32_t action,
@@ -200,10 +205,11 @@ public:
      * Returns OK on success.
      * Returns WOULD_BLOCK if the channel is full.
      * Returns DEAD_OBJECT if the channel's peer has been closed.
-     * Returns BAD_VALUE if pointerCount is less than 1 or greater than MAX_POINTERS.
+     * Returns BAD_VALUE if seq is 0 or if pointerCount is less than 1 or greater than MAX_POINTERS.
      * Other errors probably indicate that the channel is broken.
      */
     status_t publishMotionEvent(
+            uint32_t seq,
             int32_t deviceId,
             int32_t source,
             int32_t action,
@@ -222,14 +228,17 @@ public:
             const PointerCoords* pointerCoords);
 
     /* Receives the finished signal from the consumer in reply to the original dispatch signal.
-     * Returns whether the consumer handled the message.
+     * If a signal was received, returns the message sequence number,
+     * and whether the consumer handled the message.
+     *
+     * The returned sequence number is never 0 unless the operation failed.
      *
      * Returns OK on success.
      * Returns WOULD_BLOCK if there is no signal present.
      * Returns DEAD_OBJECT if the channel's peer has been closed.
      * Other errors probably indicate that the channel is broken.
      */
-    status_t receiveFinishedSignal(bool* outHandled);
+    status_t receiveFinishedSignal(uint32_t* outSeq, bool* outHandled);
 
 private:
     sp<InputChannel> mChannel;
@@ -252,24 +261,60 @@ public:
     /* Consumes an input event from the input channel and copies its contents into
      * an InputEvent object created using the specified factory.
      *
+     * Tries to combine a series of move events into larger batches whenever possible.
+     *
+     * If consumeBatches is false, then defers consuming pending batched events if it
+     * is possible for additional samples to be added to them later.  Call hasPendingBatch()
+     * to determine whether a pending batch is available to be consumed.
+     *
+     * If consumeBatches is true, then events are still batched but they are consumed
+     * immediately as soon as the input channel is exhausted.
+     *
+     * The returned sequence number is never 0 unless the operation failed.
+     *
      * Returns OK on success.
      * Returns WOULD_BLOCK if there is no event present.
      * Returns DEAD_OBJECT if the channel's peer has been closed.
      * Returns NO_MEMORY if the event could not be created.
      * Other errors probably indicate that the channel is broken.
      */
-    status_t consume(InputEventFactoryInterface* factory, InputEvent** outEvent);
+    status_t consume(InputEventFactoryInterface* factory, bool consumeBatches,
+            uint32_t* outSeq, InputEvent** outEvent);
 
-    /* Sends a finished signal to the publisher to inform it that the current message is
-     * finished processing and specifies whether the message was handled by the consumer.
+    /* Sends a finished signal to the publisher to inform it that the message
+     * with the specified sequence number has finished being process and whether
+     * the message was handled by the consumer.
      *
      * Returns OK on success.
+     * Returns BAD_VALUE if seq is 0.
      * Other errors probably indicate that the channel is broken.
      */
-    status_t sendFinishedSignal(bool handled);
+    status_t sendFinishedSignal(uint32_t seq, bool handled);
+
+    /* Returns true if there is a pending batch. */
+    bool hasPendingBatch() const;
 
 private:
     sp<InputChannel> mChannel;
+
+    // State about an event that consume would have returned except that it had to
+    // return a completed batch first.  Sequence number is non-zero if an event was deferred.
+    uint32_t mDeferredEventSeq;
+    MotionEvent mDeferredEvent;
+
+    // Batched motion events per device and source.
+    struct Batch {
+        uint32_t seq;
+        MotionEvent event;
+    };
+    Vector<Batch> mBatches;
+
+    ssize_t findBatch(int32_t deviceId, int32_t source) const;
+
+    static void initializeKeyEvent(KeyEvent* event, const InputMessage* msg);
+    static void initializeMotionEvent(MotionEvent* event, const InputMessage* msg);
+    static bool canAppendSamples(const MotionEvent* event, const InputMessage* msg);
+    static void appendSamples(MotionEvent* event, const InputMessage* msg);
 };
 
 } // namespace android
diff --git a/libs/ui/InputTransport.cpp b/libs/ui/InputTransport.cpp
index f7bcb68..98c4bdd 100644
--- a/libs/ui/InputTransport.cpp
+++ b/libs/ui/InputTransport.cpp
@@ -13,8 +13,8 @@
 // Log debug messages whenever InputChannel objects are created/destroyed
 #define DEBUG_CHANNEL_LIFECYCLE 0
 
-#define DEBUG_TRANSPORT_ACTIONS 0
 // Log debug messages about transport actions
+#define DEBUG_TRANSPORT_ACTIONS 0
 
 
 #include <cutils/log.h>
@@ -203,6 +203,7 @@ InputPublisher::~InputPublisher() {
 }
 
 status_t InputPublisher::publishKeyEvent(
+        uint32_t seq,
         int32_t deviceId,
         int32_t source,
         int32_t action,
@@ -214,16 +215,22 @@ status_t InputPublisher::publishKeyEvent(
         nsecs_t downTime,
         nsecs_t eventTime) {
 #if DEBUG_TRANSPORT_ACTIONS
-    ALOGD("channel '%s' publisher ~ publishKeyEvent: deviceId=%d, source=0x%x, "
+    ALOGD("channel '%s' publisher ~ publishKeyEvent: seq=%u, deviceId=%d, source=0x%x, "
             "action=0x%x, flags=0x%x, keyCode=%d, scanCode=%d, metaState=0x%x, repeatCount=%d,"
             "downTime=%lld, eventTime=%lld",
-            mChannel->getName().string(),
+            mChannel->getName().string(), seq,
             deviceId, source, action, flags, keyCode, scanCode, metaState, repeatCount,
             downTime, eventTime);
 #endif
 
+    if (!seq) {
+        ALOGE("Attempted to publish a key event with sequence number 0.");
+        return BAD_VALUE;
+    }
+
     InputMessage msg;
     msg.header.type = InputMessage::TYPE_KEY;
+    msg.body.key.seq = seq;
     msg.body.key.deviceId = deviceId;
     msg.body.key.source = source;
     msg.body.key.action = action;
@@ -238,6 +245,7 @@ status_t InputPublisher::publishKeyEvent(
 }
 
 status_t InputPublisher::publishMotionEvent(
+        uint32_t seq,
         int32_t deviceId,
         int32_t source,
         int32_t action,
@@ -255,16 +263,21 @@ status_t InputPublisher::publishMotionEvent(
         const PointerProperties* pointerProperties,
         const PointerCoords* pointerCoords) {
 #if DEBUG_TRANSPORT_ACTIONS
-    ALOGD("channel '%s' publisher ~ publishMotionEvent: deviceId=%d, source=0x%x, "
+    ALOGD("channel '%s' publisher ~ publishMotionEvent: seq=%u, deviceId=%d, source=0x%x, "
             "action=0x%x, flags=0x%x, edgeFlags=0x%x, metaState=0x%x, buttonState=0x%x, "
             "xOffset=%f, yOffset=%f, "
             "xPrecision=%f, yPrecision=%f, downTime=%lld, eventTime=%lld, "
             "pointerCount=%d",
-            mChannel->getName().string(),
+            mChannel->getName().string(), seq,
             deviceId, source, action, flags, edgeFlags, metaState, buttonState,
             xOffset, yOffset, xPrecision, yPrecision, downTime, eventTime, pointerCount);
 #endif
 
+    if (!seq) {
+        ALOGE("Attempted to publish a motion event with sequence number 0.");
+        return BAD_VALUE;
+    }
+
     if (pointerCount > MAX_POINTERS || pointerCount < 1) {
         ALOGE("channel '%s' publisher ~ Invalid number of pointers provided: %d.",
                 mChannel->getName().string(), pointerCount);
@@ -273,6 +286,7 @@ status_t InputPublisher::publishMotionEvent(
 
     InputMessage msg;
     msg.header.type = InputMessage::TYPE_MOTION;
+    msg.body.motion.seq = seq;
     msg.body.motion.deviceId = deviceId;
     msg.body.motion.source = source;
     msg.body.motion.action = action;
@@ -294,7 +308,7 @@ status_t InputPublisher::publishMotionEvent(
     return mChannel->sendMessage(&msg);
 }
 
-status_t InputPublisher::receiveFinishedSignal(bool* outHandled) {
+status_t InputPublisher::receiveFinishedSignal(uint32_t* outSeq, bool* outHandled) {
 #if DEBUG_TRANSPORT_ACTIONS
     ALOGD("channel '%s' publisher ~ receiveFinishedSignal",
             mChannel->getName().string());
@@ -303,6 +317,7 @@ status_t InputPublisher::receiveFinishedSignal(bool* outHandled) {
     InputMessage msg;
     status_t result = mChannel->receiveMessage(&msg);
     if (result) {
+        *outSeq = 0;
         *outHandled = false;
         return result;
     }
@@ -311,6 +326,7 @@ status_t InputPublisher::receiveFinishedSignal(bool* outHandled) {
                 mChannel->getName().string(), msg.header.type);
         return UNKNOWN_ERROR;
     }
+    *outSeq = msg.body.finished.seq;
     *outHandled = msg.body.finished.handled;
     return OK;
 }
@@ -318,98 +334,256 @@ status_t InputPublisher::receiveFinishedSignal(bool* outHandled) {
 // --- InputConsumer ---
 
 InputConsumer::InputConsumer(const sp<InputChannel>& channel) :
-        mChannel(channel) {
+        mChannel(channel), mDeferredEventSeq(0) {
 }
 
 InputConsumer::~InputConsumer() {
 }
 
-status_t InputConsumer::consume(InputEventFactoryInterface* factory, InputEvent** outEvent) {
+status_t InputConsumer::consume(InputEventFactoryInterface* factory,
+        bool consumeBatches, uint32_t* outSeq, InputEvent** outEvent) {
 #if DEBUG_TRANSPORT_ACTIONS
-    ALOGD("channel '%s' consumer ~ consume",
-            mChannel->getName().string());
+    ALOGD("channel '%s' consumer ~ consume: consumeBatches=%s",
+            mChannel->getName().string(), consumeBatches ? "true" : "false");
 #endif
 
+    *outSeq = 0;
     *outEvent = NULL;
 
-    InputMessage msg;
-    status_t result = mChannel->receiveMessage(&msg);
-    if (result) {
-        return result;
-    }
+    // Report deferred event first, if we had to end a batch earlier than we expected
+    // during the previous time consume was called.
+    if (mDeferredEventSeq) {
+        MotionEvent* motionEvent = factory->createMotionEvent();
+        if (! motionEvent) return NO_MEMORY;
 
-    switch (msg.header.type) {
-    case InputMessage::TYPE_KEY: {
-        KeyEvent* keyEvent = factory->createKeyEvent();
-        if (!keyEvent) return NO_MEMORY;
-
-        keyEvent->initialize(
-                msg.body.key.deviceId,
-                msg.body.key.source,
-                msg.body.key.action,
-                msg.body.key.flags,
-                msg.body.key.keyCode,
-                msg.body.key.scanCode,
-                msg.body.key.metaState,
-                msg.body.key.repeatCount,
-                msg.body.key.downTime,
-                msg.body.key.eventTime);
-        *outEvent = keyEvent;
-        break;
+        motionEvent->copyFrom(&mDeferredEvent, true /*keepHistory*/);
+        *outSeq = mDeferredEventSeq;
+        *outEvent = motionEvent;
+        mDeferredEventSeq = 0;
+#if DEBUG_TRANSPORT_ACTIONS
+        ALOGD("channel '%s' consumer ~ consumed deferred event, seq=%u",
+                mChannel->getName().string(), *outSeq);
+#endif
+        return OK;
     }
 
-    case AINPUT_EVENT_TYPE_MOTION: {
-        MotionEvent* motionEvent = factory->createMotionEvent();
-        if (! motionEvent) return NO_MEMORY;
+    // Fetch the next input message.
+    // Loop until an event can be returned or no additional events are received.
+    while (!*outEvent) {
+        InputMessage msg;
+        status_t result = mChannel->receiveMessage(&msg);
+        if (result) {
+            // Consume the next batched event unless batches are being held for later.
+            if (!mBatches.isEmpty() && (consumeBatches || result != WOULD_BLOCK)) {
+                MotionEvent* motionEvent = factory->createMotionEvent();
+                if (! motionEvent) return NO_MEMORY;
+
+                const Batch& batch = mBatches.top();
+                motionEvent->copyFrom(&batch.event, true /*keepHistory*/);
+                *outSeq = batch.seq;
+                *outEvent = motionEvent;
+                mBatches.pop();
+#if DEBUG_TRANSPORT_ACTIONS
+                ALOGD("channel '%s' consumer ~ consumed batch event, seq=%u",
+                        mChannel->getName().string(), *outSeq);
+#endif
+                break;
+            }
+            return result;
+        }
 
-        size_t pointerCount = msg.body.motion.pointerCount;
-        PointerProperties pointerProperties[pointerCount];
-        PointerCoords pointerCoords[pointerCount];
-        for (size_t i = 0; i < pointerCount; i++) {
-            pointerProperties[i].copyFrom(msg.body.motion.pointers[i].properties);
-            pointerCoords[i].copyFrom(msg.body.motion.pointers[i].coords);
+        switch (msg.header.type) {
+        case InputMessage::TYPE_KEY: {
+            KeyEvent* keyEvent = factory->createKeyEvent();
+            if (!keyEvent) return NO_MEMORY;
+
+            initializeKeyEvent(keyEvent, &msg);
+            *outSeq = msg.body.key.seq;
+            *outEvent = keyEvent;
+#if DEBUG_TRANSPORT_ACTIONS
+            ALOGD("channel '%s' consumer ~ consumed key event, seq=%u",
+                    mChannel->getName().string(), *outSeq);
+#endif
+            break;
         }
 
-        motionEvent->initialize(
-                msg.body.motion.deviceId,
-                msg.body.motion.source,
-                msg.body.motion.action,
-                msg.body.motion.flags,
-                msg.body.motion.edgeFlags,
-                msg.body.motion.metaState,
-                msg.body.motion.buttonState,
-                msg.body.motion.xOffset,
-                msg.body.motion.yOffset,
-                msg.body.motion.xPrecision,
-                msg.body.motion.yPrecision,
-                msg.body.motion.downTime,
-                msg.body.motion.eventTime,
-                pointerCount,
-                pointerProperties,
-                pointerCoords);
-        *outEvent = motionEvent;
-        break;
-    }
+        case AINPUT_EVENT_TYPE_MOTION: {
+            ssize_t batchIndex = findBatch(msg.body.motion.deviceId, msg.body.motion.source);
+            if (batchIndex >= 0) {
+                Batch& batch = mBatches.editItemAt(batchIndex);
+                if (canAppendSamples(&batch.event, &msg)) {
+                    // Send finished message for the earlier part of the batch.
+                    // Claim that we handled the event.  (The dispatcher doesn't care either
+                    // way at the moment.)
+                    status_t status = sendFinishedSignal(batch.seq, true);
+                    if (status) {
+                        return status;
+                    }
+
+                    // Append to the batch and save the new sequence number for the tail end.
+                    appendSamples(&batch.event, &msg);
+                    batch.seq = msg.body.motion.seq;
+#if DEBUG_TRANSPORT_ACTIONS
+                    ALOGD("channel '%s' consumer ~ appended to batch event",
+                            mChannel->getName().string());
+#endif
+                    break;
+                } else {
+                    MotionEvent* motionEvent = factory->createMotionEvent();
+                    if (! motionEvent) return NO_MEMORY;
+
+                    // We cannot append to the batch in progress, so we need to consume
+                    // the previous batch right now and defer the new event until later.
+                    mDeferredEventSeq = msg.body.motion.seq;
+                    initializeMotionEvent(&mDeferredEvent, &msg);
+
+                    // Return the end of the previous batch.
+                    motionEvent->copyFrom(&batch.event, true /*keepHistory*/);
+                    *outSeq = batch.seq;
+                    *outEvent = motionEvent;
+                    mBatches.removeAt(batchIndex);
+#if DEBUG_TRANSPORT_ACTIONS
+                    ALOGD("channel '%s' consumer ~ consumed batch event and "
+                            "deferred current event, seq=%u",
+                            mChannel->getName().string(), *outSeq);
+#endif
+                    break;
+                }
+            }
+
+            // Start a new batch if needed.
+            if (msg.body.motion.action == AMOTION_EVENT_ACTION_MOVE
+                    || msg.body.motion.action == AMOTION_EVENT_ACTION_HOVER_MOVE) {
+                mBatches.push();
+                Batch& batch = mBatches.editTop();
+                batch.seq = msg.body.motion.seq;
+                initializeMotionEvent(&batch.event, &msg);
+#if DEBUG_TRANSPORT_ACTIONS
+                ALOGD("channel '%s' consumer ~ started batch event",
+                        mChannel->getName().string());
+#endif
+                break;
+            }
 
-    default:
-        ALOGE("channel '%s' consumer ~ Received unexpected message of type %d",
-                mChannel->getName().string(), msg.header.type);
-        return UNKNOWN_ERROR;
-    }
+            MotionEvent* motionEvent = factory->createMotionEvent();
+            if (! motionEvent) return NO_MEMORY;
 
+            initializeMotionEvent(motionEvent, &msg);
+            *outSeq = msg.body.motion.seq;
+            *outEvent = motionEvent;
+#if DEBUG_TRANSPORT_ACTIONS
+            ALOGD("channel '%s' consumer ~ consumed motion event, seq=%u",
+                    mChannel->getName().string(), *outSeq);
+#endif
+            break;
+        }
+
+        default:
+            ALOGE("channel '%s' consumer ~ Received unexpected message of type %d",
+                    mChannel->getName().string(), msg.header.type);
+            return UNKNOWN_ERROR;
+        }
+    }
     return OK;
 }
 
-status_t InputConsumer::sendFinishedSignal(bool handled) {
+status_t InputConsumer::sendFinishedSignal(uint32_t seq, bool handled) {
 #if DEBUG_TRANSPORT_ACTIONS
-    ALOGD("channel '%s' consumer ~ sendFinishedSignal: handled=%d",
-            mChannel->getName().string(), handled);
+    ALOGD("channel '%s' consumer ~ sendFinishedSignal: seq=%u, handled=%s",
+            mChannel->getName().string(), seq, handled ? "true" : "false");
 #endif
 
+    if (!seq) {
+        ALOGE("Attempted to send a finished signal with sequence number 0.");
+        return BAD_VALUE;
+    }
+
     InputMessage msg;
     msg.header.type = InputMessage::TYPE_FINISHED;
+    msg.body.finished.seq = seq;
     msg.body.finished.handled = handled;
     return mChannel->sendMessage(&msg);
 }
 
+bool InputConsumer::hasPendingBatch() const {
+    return !mBatches.isEmpty();
+}
+
+ssize_t InputConsumer::findBatch(int32_t deviceId, int32_t source) const {
+    for (size_t i = 0; i < mBatches.size(); i++) {
+        const Batch& batch = mBatches.itemAt(i);
+        if (batch.event.getDeviceId() == deviceId && batch.event.getSource() == source) {
+            return i;
+        }
+    }
+    return -1;
+}
+
+void InputConsumer::initializeKeyEvent(KeyEvent* event, const InputMessage* msg) {
+    event->initialize(
+            msg->body.key.deviceId,
+            msg->body.key.source,
+            msg->body.key.action,
+            msg->body.key.flags,
+            msg->body.key.keyCode,
+            msg->body.key.scanCode,
+            msg->body.key.metaState,
+            msg->body.key.repeatCount,
+            msg->body.key.downTime,
+            msg->body.key.eventTime);
+}
+
+void InputConsumer::initializeMotionEvent(MotionEvent* event, const InputMessage* msg) {
+    size_t pointerCount = msg->body.motion.pointerCount;
+    PointerProperties pointerProperties[pointerCount];
+    PointerCoords pointerCoords[pointerCount];
+    for (size_t i = 0; i < pointerCount; i++) {
+        pointerProperties[i].copyFrom(msg->body.motion.pointers[i].properties);
+        pointerCoords[i].copyFrom(msg->body.motion.pointers[i].coords);
+    }
+
+    event->initialize(
+            msg->body.motion.deviceId,
+            msg->body.motion.source,
+            msg->body.motion.action,
+            msg->body.motion.flags,
+            msg->body.motion.edgeFlags,
+            msg->body.motion.metaState,
+            msg->body.motion.buttonState,
+            msg->body.motion.xOffset,
+            msg->body.motion.yOffset,
+            msg->body.motion.xPrecision,
+            msg->body.motion.yPrecision,
+            msg->body.motion.downTime,
+            msg->body.motion.eventTime,
+            pointerCount,
+            pointerProperties,
+            pointerCoords);
+}
+
+bool InputConsumer::canAppendSamples(const MotionEvent* event, const InputMessage *msg) {
+    size_t pointerCount = msg->body.motion.pointerCount;
+    if (event->getPointerCount() != pointerCount
+            || event->getAction() != msg->body.motion.action) {
+        return false;
+    }
+    for (size_t i = 0; i < pointerCount; i++) {
+        if (*event->getPointerProperties(i) != msg->body.motion.pointers[i].properties) {
+            return false;
+        }
+    }
+    return true;
+}
+
+void InputConsumer::appendSamples(MotionEvent* event, const InputMessage* msg) {
+    size_t pointerCount = msg->body.motion.pointerCount;
+    PointerCoords pointerCoords[pointerCount];
+    for (size_t i = 0; i < pointerCount; i++) {
+        pointerCoords[i].copyFrom(msg->body.motion.pointers[i].coords);
+    }
+
+    event->setMetaState(event->getMetaState() | msg->body.motion.metaState);
+    event->addSample(msg->body.motion.eventTime, pointerCoords);
+}
+
 } // namespace android
diff --git a/libs/ui/tests/InputChannel_test.cpp b/libs/ui/tests/InputChannel_test.cpp
index c73dc2f..ee422fe 100644
--- a/libs/ui/tests/InputChannel_test.cpp
+++ b/libs/ui/tests/InputChannel_test.cpp
@@ -90,6 +90,7 @@ TEST_F(InputChannelTest, OpenInputChannelPair_ReturnsAPairOfConnectedChannels) {
     InputMessage clientReply;
     memset(&clientReply, 0, sizeof(InputMessage));
     clientReply.header.type = InputMessage::TYPE_FINISHED;
+    clientReply.body.finished.seq = 0x11223344;
     clientReply.body.finished.handled = true;
     EXPECT_EQ(OK, clientChannel->sendMessage(&clientReply))
             << "client channel should be able to send message to server channel";
@@ -99,6 +100,8 @@ TEST_F(InputChannelTest, OpenInputChannelPair_ReturnsAPairOfConnectedChannels) {
             << "server channel should be able to receive message from client channel";
     EXPECT_EQ(clientReply.header.type, serverReply.header.type)
             << "server channel should receive the correct message from client channel";
+    EXPECT_EQ(clientReply.body.finished.seq, serverReply.body.finished.seq)
+            << "server channel should receive the correct message from client channel";
     EXPECT_EQ(clientReply.body.finished.handled, serverReply.body.finished.handled)
             << "server channel should receive the correct message from client channel";
 }
diff --git a/libs/ui/tests/InputPublisherAndConsumer_test.cpp b/libs/ui/tests/InputPublisherAndConsumer_test.cpp
index a0ee94b..3303053 100644
--- a/libs/ui/tests/InputPublisherAndConsumer_test.cpp
+++ b/libs/ui/tests/InputPublisherAndConsumer_test.cpp
@@ -69,6 +69,7 @@ TEST_F(InputPublisherAndConsumerTest, GetChannel_ReturnsTheChannel) {
 void InputPublisherAndConsumerTest::PublishAndConsumeKeyEvent() {
     status_t status;
 
+    const uint32_t seq = 15;
     const int32_t deviceId = 1;
     const int32_t source = AINPUT_SOURCE_KEYBOARD;
     const int32_t action = AKEY_EVENT_ACTION_DOWN;
@@ -80,13 +81,14 @@ void InputPublisherAndConsumerTest::PublishAndConsumeKeyEvent() {
     const nsecs_t downTime = 3;
     const nsecs_t eventTime = 4;
 
-    status = mPublisher->publishKeyEvent(deviceId, source, action, flags,
+    status = mPublisher->publishKeyEvent(seq, deviceId, source, action, flags,
             keyCode, scanCode, metaState, repeatCount, downTime, eventTime);
     ASSERT_EQ(OK, status)
             << "publisher publishKeyEvent should return OK";
 
+    uint32_t consumeSeq;
     InputEvent* event;
-    status = mConsumer->consume(& mEventFactory, & event);
+    status = mConsumer->consume(&mEventFactory, true /*consumeBatches*/, &consumeSeq, &event);
     ASSERT_EQ(OK, status)
             << "consumer consume should return OK";
 
@@ -96,6 +98,7 @@ void InputPublisherAndConsumerTest::PublishAndConsumeKeyEvent() {
             << "consumer should have returned a key event";
 
     KeyEvent* keyEvent = static_cast<KeyEvent*>(event);
+    EXPECT_EQ(seq, consumeSeq);
     EXPECT_EQ(deviceId, keyEvent->getDeviceId());
     EXPECT_EQ(source, keyEvent->getSource());
     EXPECT_EQ(action, keyEvent->getAction());
@@ -107,14 +110,17 @@ void InputPublisherAndConsumerTest::PublishAndConsumeKeyEvent() {
     EXPECT_EQ(downTime, keyEvent->getDownTime());
     EXPECT_EQ(eventTime, keyEvent->getEventTime());
 
-    status = mConsumer->sendFinishedSignal(true);
+    status = mConsumer->sendFinishedSignal(seq, true);
     ASSERT_EQ(OK, status)
             << "consumer sendFinishedSignal should return OK";
 
+    uint32_t finishedSeq = 0;
     bool handled = false;
-    status = mPublisher->receiveFinishedSignal(&handled);
+    status = mPublisher->receiveFinishedSignal(&finishedSeq, &handled);
     ASSERT_EQ(OK, status)
             << "publisher receiveFinishedSignal should return OK";
+    ASSERT_EQ(seq, finishedSeq)
+            << "publisher receiveFinishedSignal should have returned the original sequence number";
     ASSERT_TRUE(handled)
             << "publisher receiveFinishedSignal should have set handled to consumer's reply";
 }
@@ -122,6 +128,7 @@ void InputPublisherAndConsumerTest::PublishAndConsumeKeyEvent() {
 void InputPublisherAndConsumerTest::PublishAndConsumeMotionEvent() {
     status_t status;
 
+    const uint32_t seq = 15;
     const int32_t deviceId = 1;
     const int32_t source = AINPUT_SOURCE_TOUCHSCREEN;
     const int32_t action = AMOTION_EVENT_ACTION_MOVE;
@@ -155,15 +162,16 @@ void InputPublisherAndConsumerTest::PublishAndConsumeMotionEvent() {
         pointerCoords[i].setAxisValue(AMOTION_EVENT_AXIS_ORIENTATION, 3.5 * i);
     }
 
-    status = mPublisher->publishMotionEvent(deviceId, source, action, flags, edgeFlags,
+    status = mPublisher->publishMotionEvent(seq, deviceId, source, action, flags, edgeFlags,
             metaState, buttonState, xOffset, yOffset, xPrecision, yPrecision,
             downTime, eventTime, pointerCount,
             pointerProperties, pointerCoords);
     ASSERT_EQ(OK, status)
             << "publisher publishMotionEvent should return OK";
 
+    uint32_t consumeSeq;
     InputEvent* event;
-    status = mConsumer->consume(& mEventFactory, & event);
+    status = mConsumer->consume(&mEventFactory, true /*consumeBatches*/, &consumeSeq, &event);
     ASSERT_EQ(OK, status)
             << "consumer consume should return OK";
 
@@ -173,6 +181,7 @@ void InputPublisherAndConsumerTest::PublishAndConsumeMotionEvent() {
             << "consumer should have returned a motion event";
 
     MotionEvent* motionEvent = static_cast<MotionEvent*>(event);
+    EXPECT_EQ(seq, consumeSeq);
     EXPECT_EQ(deviceId, motionEvent->getDeviceId());
     EXPECT_EQ(source, motionEvent->getSource());
     EXPECT_EQ(action, motionEvent->getAction());
@@ -216,14 +225,17 @@ void InputPublisherAndConsumerTest::PublishAndConsumeMotionEvent() {
                 motionEvent->getOrientation(i));
     }
 
-    status = mConsumer->sendFinishedSignal(false);
+    status = mConsumer->sendFinishedSignal(seq, false);
     ASSERT_EQ(OK, status)
             << "consumer sendFinishedSignal should return OK";
 
+    uint32_t finishedSeq = 0;
     bool handled = true;
-    status = mPublisher->receiveFinishedSignal(&handled);
+    status = mPublisher->receiveFinishedSignal(&finishedSeq, &handled);
     ASSERT_EQ(OK, status)
             << "publisher receiveFinishedSignal should return OK";
+    ASSERT_EQ(seq, finishedSeq)
+            << "publisher receiveFinishedSignal should have returned the original sequence number";
     ASSERT_FALSE(handled)
             << "publisher receiveFinishedSignal should have set handled to consumer's reply";
 }
@@ -242,7 +254,7 @@ TEST_F(InputPublisherAndConsumerTest, PublishMotionEvent_WhenPointerCountLessTha
     PointerProperties pointerProperties[pointerCount];
     PointerCoords pointerCoords[pointerCount];
 
-    status = mPublisher->publishMotionEvent(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    status = mPublisher->publishMotionEvent(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
             pointerCount, pointerProperties, pointerCoords);
     ASSERT_EQ(BAD_VALUE, status)
             << "publisher publishMotionEvent should return BAD_VALUE";
@@ -258,7 +270,7 @@ TEST_F(InputPublisherAndConsumerTest, PublishMotionEvent_WhenPointerCountGreater
         pointerCoords[i].clear();
     }
 
-    status = mPublisher->publishMotionEvent(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    status = mPublisher->publishMotionEvent(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
             pointerCount, pointerProperties, pointerCoords);
     ASSERT_EQ(BAD_VALUE, status)
             << "publisher publishMotionEvent should return BAD_VALUE";
diff --git a/services/input/InputDispatcher.cpp b/services/input/InputDispatcher.cpp
index a63b6f5..d04aa68 100644
--- a/services/input/InputDispatcher.cpp
+++ b/services/input/InputDispatcher.cpp
@@ -1872,7 +1872,7 @@ void InputDispatcher::startDispatchCycleLocked(nsecs_t currentTime,
             KeyEntry* keyEntry = static_cast<KeyEntry*>(eventEntry);
 
             // Publish the key event.
-            status = connection->inputPublisher.publishKeyEvent(
+            status = connection->inputPublisher.publishKeyEvent(dispatchEntry->seq,
                     keyEntry->deviceId, keyEntry->source,
                     dispatchEntry->resolvedAction, dispatchEntry->resolvedFlags,
                     keyEntry->keyCode, keyEntry->scanCode,
@@ -1916,7 +1916,7 @@ void InputDispatcher::startDispatchCycleLocked(nsecs_t currentTime,
             }
 
             // Publish the motion event.
-            status = connection->inputPublisher.publishMotionEvent(
+            status = connection->inputPublisher.publishMotionEvent(dispatchEntry->seq,
                     motionEntry->deviceId, motionEntry->source,
                     dispatchEntry->resolvedAction, dispatchEntry->resolvedFlags,
                     motionEntry->edgeFlags, motionEntry->metaState, motionEntry->buttonState,
@@ -1967,10 +1967,10 @@ void InputDispatcher::startDispatchCycleLocked(nsecs_t currentTime,
 }
 
 void InputDispatcher::finishDispatchCycleLocked(nsecs_t currentTime,
-        const sp<Connection>& connection, bool handled) {
+        const sp<Connection>& connection, uint32_t seq, bool handled) {
 #if DEBUG_DISPATCH_CYCLE
-    ALOGD("channel '%s' ~ finishDispatchCycle - handled=%s",
-            connection->getInputChannelName(), toString(handled));
+    ALOGD("channel '%s' ~ finishDispatchCycle - seq=%u, handled=%s",
+            connection->getInputChannelName(), seq, toString(handled));
 #endif
 
     connection->inputPublisherBlocked = false;
@@ -1981,7 +1981,7 @@ void InputDispatcher::finishDispatchCycleLocked(nsecs_t currentTime,
     }
 
     // Notify other system components and prepare to start the next dispatch cycle.
-    onDispatchCycleFinishedLocked(currentTime, connection, handled);
+    onDispatchCycleFinishedLocked(currentTime, connection, seq, handled);
 }
 
 void InputDispatcher::abortBrokenDispatchCycleLocked(nsecs_t currentTime,
@@ -2047,12 +2047,13 @@ int InputDispatcher::handleReceiveCallback(int fd, int events, void* data) {
             bool gotOne = false;
             status_t status;
             for (;;) {
-                bool handled = false;
-                status = connection->inputPublisher.receiveFinishedSignal(&handled);
+                uint32_t seq;
+                bool handled;
+                status = connection->inputPublisher.receiveFinishedSignal(&seq, &handled);
                 if (status) {
                     break;
                 }
-                d->finishDispatchCycleLocked(currentTime, connection, handled);
+                d->finishDispatchCycleLocked(currentTime, connection, seq, handled);
                 gotOne = true;
             }
             if (gotOne) {
@@ -3171,10 +3172,11 @@ ssize_t InputDispatcher::getConnectionIndexLocked(const sp<InputChannel>& inputC
 }
 
 void InputDispatcher::onDispatchCycleFinishedLocked(
-        nsecs_t currentTime, const sp<Connection>& connection, bool handled) {
+        nsecs_t currentTime, const sp<Connection>& connection, uint32_t seq, bool handled) {
     CommandEntry* commandEntry = postCommandLocked(
             & InputDispatcher::doDispatchCycleFinishedLockedInterruptible);
     commandEntry->connection = connection;
+    commandEntry->seq = seq;
     commandEntry->handled = handled;
 }
 
@@ -3268,12 +3270,13 @@ void InputDispatcher::doInterceptKeyBeforeDispatchingLockedInterruptible(
 void InputDispatcher::doDispatchCycleFinishedLockedInterruptible(
         CommandEntry* commandEntry) {
     sp<Connection> connection = commandEntry->connection;
+    uint32_t seq = commandEntry->seq;
     bool handled = commandEntry->handled;
 
-    if (!connection->waitQueue.isEmpty()) {
-        // Handle post-event policy actions.
+    // Handle post-event policy actions.
+    DispatchEntry* dispatchEntry = connection->findWaitQueueEntry(seq);
+    if (dispatchEntry) {
         bool restartEvent;
-        DispatchEntry* dispatchEntry = connection->waitQueue.head;
         if (dispatchEntry->eventEntry->type == EventEntry::TYPE_KEY) {
             KeyEntry* keyEntry = static_cast<KeyEntry*>(dispatchEntry->eventEntry);
             restartEvent = afterKeyEventLockedInterruptible(connection,
@@ -3290,8 +3293,8 @@ void InputDispatcher::doDispatchCycleFinishedLockedInterruptible(
         // Note that because the lock might have been released, it is possible that the
         // contents of the wait queue to have been drained, so we need to double-check
         // a few things.
-        if (connection->waitQueue.head == dispatchEntry) {
-            connection->waitQueue.dequeueAtHead();
+        if (dispatchEntry == connection->findWaitQueueEntry(seq)) {
+            connection->waitQueue.dequeue(dispatchEntry);
             if (restartEvent && connection->status == Connection::STATUS_NORMAL) {
                 connection->outboundQueue.enqueueAtHead(dispatchEntry);
             } else {
@@ -3635,8 +3638,11 @@ InputDispatcher::MotionEntry::~MotionEntry() {
 
 // --- InputDispatcher::DispatchEntry ---
 
+volatile int32_t InputDispatcher::DispatchEntry::sNextSeqAtomic;
+
 InputDispatcher::DispatchEntry::DispatchEntry(EventEntry* eventEntry,
         int32_t targetFlags, float xOffset, float yOffset, float scaleFactor) :
+        seq(nextSeq()),
         eventEntry(eventEntry), targetFlags(targetFlags),
         xOffset(xOffset), yOffset(yOffset), scaleFactor(scaleFactor),
         resolvedAction(0), resolvedFlags(0) {
@@ -3647,6 +3653,15 @@ InputDispatcher::DispatchEntry::~DispatchEntry() {
     eventEntry->release();
 }
 
+uint32_t InputDispatcher::DispatchEntry::nextSeq() {
+    // Sequence number 0 is reserved and will never be returned.
+    uint32_t seq;
+    do {
+        seq = android_atomic_inc(&sNextSeqAtomic);
+    } while (!seq);
+    return seq;
+}
+
 
 // --- InputDispatcher::InputState ---
 
@@ -3999,11 +4014,21 @@ const char* InputDispatcher::Connection::getStatusLabel() const {
     }
 }
 
+InputDispatcher::DispatchEntry* InputDispatcher::Connection::findWaitQueueEntry(uint32_t seq) {
+    for (DispatchEntry* entry = waitQueue.head; entry != NULL; entry = entry->next) {
+        if (entry->seq == seq) {
+            return entry;
+        }
+    }
+    return NULL;
+}
+
 
 // --- InputDispatcher::CommandEntry ---
 
 InputDispatcher::CommandEntry::CommandEntry(Command command) :
-    command(command), eventTime(0), keyEntry(NULL), userActivityEventType(0), handled(false) {
+    command(command), eventTime(0), keyEntry(NULL), userActivityEventType(0),
+    seq(0), handled(false) {
 }
 
 InputDispatcher::CommandEntry::~CommandEntry() {
diff --git a/services/input/InputDispatcher.h b/services/input/InputDispatcher.h
index 1311465..03a824b 100644
--- a/services/input/InputDispatcher.h
+++ b/services/input/InputDispatcher.h
@@ -27,6 +27,7 @@
 #include <utils/String8.h>
 #include <utils/Looper.h>
 #include <utils/BitSet.h>
+#include <cutils/atomic.h>
 
 #include <stddef.h>
 #include <unistd.h>
@@ -522,6 +523,8 @@ private:
 
     // Tracks the progress of dispatching a particular event to a particular connection.
     struct DispatchEntry : Link<DispatchEntry> {
+        const uint32_t seq; // unique sequence number, never 0
+
         EventEntry* eventEntry; // the event to dispatch
         int32_t targetFlags;
         float xOffset;
@@ -543,6 +546,11 @@ private:
         inline bool isSplit() const {
             return targetFlags & InputTarget::FLAG_SPLIT;
         }
+
+    private:
+        static volatile int32_t sNextSeqAtomic;
+
+        static uint32_t nextSeq();
     };
 
     // A command entry captures state and behavior for an action to be performed in the
@@ -578,6 +586,7 @@ private:
         sp<InputApplicationHandle> inputApplicationHandle;
         sp<InputWindowHandle> inputWindowHandle;
         int32_t userActivityEventType;
+        uint32_t seq;
         bool handled;
     };
 
@@ -797,6 +806,8 @@ private:
         inline const char* getInputChannelName() const { return inputChannel->getName().string(); }
 
         const char* getStatusLabel() const;
+
+        DispatchEntry* findWaitQueueEntry(uint32_t seq);
     };
 
     enum DropReason {
@@ -1000,7 +1011,7 @@ private:
             EventEntry* eventEntry, const InputTarget* inputTarget, int32_t dispatchMode);
     void startDispatchCycleLocked(nsecs_t currentTime, const sp<Connection>& connection);
     void finishDispatchCycleLocked(nsecs_t currentTime, const sp<Connection>& connection,
-            bool handled);
+            uint32_t seq, bool handled);
     void abortBrokenDispatchCycleLocked(nsecs_t currentTime, const sp<Connection>& connection,
             bool notify);
     void drainDispatchQueueLocked(Queue<DispatchEntry>* queue);
@@ -1034,7 +1045,7 @@ private:
 
     // Interesting events that we might like to log or tell the framework about.
     void onDispatchCycleFinishedLocked(
-            nsecs_t currentTime, const sp<Connection>& connection, bool handled);
+            nsecs_t currentTime, const sp<Connection>& connection, uint32_t seq, bool handled);
     void onDispatchCycleBrokenLocked(
             nsecs_t currentTime, const sp<Connection>& connection);
     void onANRLocked(