Speculatively schedule input consumption

With the new tuned vsync offset, vsyncs are likely to occur shortly
after the input is received, meaning we will empty the input queue,
and thus won't schedule input consumption until more input is
received. If an application then speculatively posts draw commands to
the main looper faster than 60 hz, it will eventually end up blocking
in eglSwapBuffers. Since we're blocking in eglSwapBuffers, we won't
even schedule consumption until after the current frame (8-16ms), and
it's entirely likely we won't actually get around to consuming input
until after the next frame (another 16 ms of latency). This means we
can often go 16-32ms without processing any input events, causing
very noticeable amounts of jank.

Rather than waiting for the next input event to schedule input
consumption, speculatively schedule it every frame as long as we've
consumed some motion batch during this frame.

Bug: 11398045
Change-Id: I25e46308e00e9f9de00a1d8906f6b0e0f2e845b4

1 files changed, 6 insertions, 3 deletions

diff --git a/core/java/android/view/InputEventReceiver.java b/core/java/android/view/InputEventReceiver.java
index f5ee7ed..25972e7 100644
--- a/core/java/android/view/InputEventReceiver.java
+++ b/core/java/android/view/InputEventReceiver.java
@@ -48,7 +48,7 @@ public abstract class InputEventReceiver {
             InputChannel inputChannel, MessageQueue messageQueue);
     private static native void nativeDispose(int receiverPtr);
     private static native void nativeFinishInputEvent(int receiverPtr, int seq, boolean handled);
-    private static native void nativeConsumeBatchedInputEvents(int receiverPtr,
+    private static native boolean nativeConsumeBatchedInputEvents(int receiverPtr,
             long frameTimeNanos);
 
     /**
@@ -165,14 +165,17 @@ public abstract class InputEventReceiver {
      *
      * @param frameTimeNanos The time in the {@link System#nanoTime()} time base
      * when the current display frame started rendering, or -1 if unknown.
+     *
+     * @return Whether a batch was consumed
      */
-    public final void consumeBatchedInputEvents(long frameTimeNanos) {
+    public final boolean consumeBatchedInputEvents(long frameTimeNanos) {
         if (mReceiverPtr == 0) {
             Log.w(TAG, "Attempted to consume batched input events but the input event "
                     + "receiver has already been disposed.");
         } else {
-            nativeConsumeBatchedInputEvents(mReceiverPtr, frameTimeNanos);
+            return nativeConsumeBatchedInputEvents(mReceiverPtr, frameTimeNanos);
         }
+        return false;
     }
 
     // Called from native code.