Merge "Actually do not hold WM lock while closing transaction" into oc-dev (06f3e97e) · Commits · e / os / android_frameworks_base

services/core/java/com/android/server/wm/WindowAnimator.java

+4 −1

Original line number	Diff line number	Diff line
		@@ -228,7 +228,10 @@ public class WindowAnimator {
		Slog.wtf(TAG, "Unhandled exception in Window Manager", e);
		} finally {
		if (transactionOpen) {
		mService.closeSurfaceTransaction();

		// Do not hold window manager lock while closing the transaction, as this might be
		// blocking until the next frame, which can lead to total lock starvation.
		mService.closeSurfaceTransaction(false /* withLockHeld */);
		if (SHOW_TRANSACTIONS) Slog.i(TAG, "<<< CLOSE TRANSACTION animate");
		}
		}

+16 −0

Original line number	Diff line number	Diff line
		@@ -896,10 +896,26 @@ public class WindowManagerService extends IWindowManager.Stub
		}

		void closeSurfaceTransaction() {
		closeSurfaceTransaction(true /* withLockHeld */);
		}

		/**
		* Closes a surface transaction.
		*
		* @param withLockHeld Whether to acquire the window manager while doing so. In some cases
		* holding the lock my lead to starvation in WM in case closeTransaction
		* blocks and we call it repeatedly, like we do for animations.
		*/
		void closeSurfaceTransaction(boolean withLockHeld) {
		synchronized (mWindowMap) {
		if (mRoot.mSurfaceTraceEnabled) {
		mRoot.mRemoteEventTrace.closeSurfaceTransaction();
		}
		if (withLockHeld) {
		SurfaceControl.closeTransaction();
		}
		}
		if (!withLockHeld) {
		SurfaceControl.closeTransaction();
		}
		}