Update rotation without holding the WOL lock.

We need to make sure to only ever update the orientation of the
device from WindowOrientationListener when we're not holding the WOL
class lock, otherwise we can deadlock when WMS calls into us to set
the orientation based on an apps preference.

Bug: 23491348
Change-Id: Ifeded4d5d1dc923fa2ce0473bc4b7fe950dc0cfd

diff --git a/services/core/java/com/android/server/policy/WindowOrientationListener.java b/services/core/java/com/android/server/policy/WindowOrientationListener.java
index 8b3c036..9916223 100644 (file)
--- a/services/core/java/com/android/server/policy/WindowOrientationListener.java
+++ b/services/core/java/com/android/server/policy/WindowOrientationListener.java
@@ -217,6 +217,8 @@ public abstract class WindowOrientationListener {
      * It is called each time the orientation determination transitions from being
      * uncertain to being certain again, even if it is the same orientation as before.
      *
+     * This should only be called on the Handler thread.
+     *
      * @param rotation The new orientation of the device, one of the Surface.ROTATION_* constants.
      * @see android.view.Surface
      */
@@ -995,9 +997,13 @@ public abstract class WindowOrientationListener {
 
         @Override
         public void onSensorChanged(SensorEvent event) {
+            int newRotation;
             synchronized (mLock) {
                 mDesiredRotation = (int) event.values[0];
-                evaluateRotationChangeLocked();
+                newRotation = evaluateRotationChangeLocked();
+            }
+            if (newRotation >=0) {
+                onProposedRotationChanged(newRotation);
             }
         }
 
@@ -1023,18 +1029,19 @@ public abstract class WindowOrientationListener {
             unscheduleRotationEvaluationLocked();
         }
 
-        public void evaluateRotationChangeLocked() {
+        public int evaluateRotationChangeLocked() {
             unscheduleRotationEvaluationLocked();
             if (mDesiredRotation == mProposedRotation) {
-                return;
+                return -1;
             }
             final long now = SystemClock.elapsedRealtimeNanos();
             if (isDesiredRotationAcceptableLocked(now)) {
                 mProposedRotation = mDesiredRotation;
-                onProposedRotationChanged(mProposedRotation);
+                return mProposedRotation;
             } else {
                 scheduleRotationEvaluationIfNecessaryLocked(now);
             }
+            return -1;
         }
 
         private boolean isDesiredRotationAcceptableLocked(long now) {
@@ -1090,9 +1097,13 @@ public abstract class WindowOrientationListener {
         private Runnable mRotationEvaluator = new Runnable() {
             @Override
             public void run() {
+                int newRotation;
                 synchronized (mLock) {
                     mRotationEvaluationScheduled = false;
-                    evaluateRotationChangeLocked();
+                    newRotation = evaluateRotationChangeLocked();
+                }
+                if (newRotation >= 0) {
+                    onProposedRotationChanged(newRotation);
                 }
             }
         };