Merge "SurfaceView: Ensure the Surface remains valid with SurfaceHolder#lockCanvas"

core/java/android/view/SurfaceView.java

@@ -119,6 +119,10 @@ public class SurfaceView extends View implements ViewRootImpl.SurfaceChangedCall
     final int[] mLocation = new int[2];
 
     @UnsupportedAppUsage
+    // Used to ensure the Surface remains valid between SurfaceHolder#lockCanvas and
+    // SurfaceHolder#unlockCanvasAndPost calls. This prevents SurfaceView from destroying or
+    // invalidating the Surface. This means this lock should be acquired when destroying the
+    // BlastBufferQueue.
     final ReentrantLock mSurfaceLock = new ReentrantLock();
     @UnsupportedAppUsage
     final Surface mSurface = new Surface();       // Current surface in use
@@ -724,14 +728,18 @@ public class SurfaceView extends View implements ViewRootImpl.SurfaceChangedCall
 
     private void releaseSurfaces(boolean releaseSurfacePackage) {
         mSurfaceAlpha = 1f;
-        mSurface.destroy();
-
-        synchronized (mSurfaceControlLock) {
+        try {
+            mSurfaceLock.lock();
+            mSurface.destroy();
             if (mBlastBufferQueue != null) {
                 mBlastBufferQueue.destroy();
                 mBlastBufferQueue = null;
             }
+        } finally {
+            mSurfaceLock.unlock();
+        }
 
+        synchronized (mSurfaceControlLock) {
             final Transaction transaction = new Transaction();
             if (mSurfaceControl != null) {
                 transaction.remove(mSurfaceControl);
@@ -1232,16 +1240,21 @@ public class SurfaceView extends View implements ViewRootImpl.SurfaceChangedCall
                     .build();
         }
 
-        // Always recreate the IGBP for compatibility. This can be optimized in the future but
-        // the behavior change will need to be gated by SDK version.
-        if (mBlastBufferQueue != null) {
-            mBlastBufferQueue.destroy();
-        }
         mTransformHint = viewRoot.getBufferTransformHint();
         mBlastSurfaceControl.setTransformHint(mTransformHint);
 
-        mBlastBufferQueue = new BLASTBufferQueue(name, false /* updateDestinationFrame */);
-        mBlastBufferQueue.update(mBlastSurfaceControl, mSurfaceWidth, mSurfaceHeight, mFormat);
+        // Always recreate the IGBP for compatibility. This can be optimized in the future but
+        // the behavior change will need to be gated by SDK version.
+        try {
+            mSurfaceLock.lock();
+            if (mBlastBufferQueue != null) {
+                mBlastBufferQueue.destroy();
+            }
+            mBlastBufferQueue = new BLASTBufferQueue(name, false /* updateDestinationFrame */);
+            mBlastBufferQueue.update(mBlastSurfaceControl, mSurfaceWidth, mSurfaceHeight, mFormat);
+        } finally {
+            mSurfaceLock.unlock();
+        }
         mBlastBufferQueue.setTransactionHangCallback(ViewRootImpl.sTransactionHangCallback);
     }
 
@@ -1814,7 +1827,14 @@ public class SurfaceView extends View implements ViewRootImpl.SurfaceChangedCall
             // so the next connect will always work if we end up reusing
             // the surface.
             if (mSurface.isValid()) {
-                mSurface.forceScopedDisconnect();
+                // We need to grab this lock since mSurface.forceScopedDisconnect
+                // will free buffers from the queue.
+                try {
+                    mSurfaceLock.lock();
+                    mSurface.forceScopedDisconnect();
+                } finally {
+                    mSurfaceLock.unlock();
+                }
             }
         }
     }