Commit 05f0664b authored Oct 12, 2023 by Evan Rosky

Support playNow on queued SLEEP transits

When a transition is queued, we usually post the onCollectStarted
callback to avoid ordering issues w/ the prior transition. This
means that anything in the handler queue will execute before
onCollectStarted. Again, this is desired normally and it means
those actions will be collected in the new transition.

However, SLEEP transitions are currently treated as empty
sentinels (at-least today). While there's nothing wrong with
collecting changes in SLEEP transitions, we still have some
transitions (eg. around keyguard) that can race with it, so
to reduce those races short-term, this adds a check for SLEEP
when dequeuing and start that immediately vs. posting.

Bug: 304713150
Test: Existing tests pass.
Change-Id: Id234414c220367a2e971fa29cf03ba631c7564f1

parent 7273f041

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

+14 −6

Original line number	Diff line number	Diff line
		@@ -1005,6 +1005,13 @@ class TransitionController {
		// legacy sync
		mSyncEngine.startSyncSet(queued.mLegacySync);
		}
		if (queued.mTransition != null
		&& queued.mTransition.mType == WindowManager.TRANSIT_SLEEP) {
		// SLEEP transitions are special in that they don't collect anything (in fact if they
		// do collect things it can cause problems). So, we need to run it's onCollectStarted
		// immediately.
		queued.mOnStartCollect.onCollectStarted(true /* deferred */);
		} else {
		// Post this so that the now-playing transition logic isn't interrupted.
		mAtm.mH.post(() -> {
		synchronized (mAtm.mGlobalLock) {
		@@ -1012,6 +1019,7 @@ class TransitionController {
		}
		});
		}
		}

		void moveToPlaying(Transition transition) {
		if (transition == mCollectingTransition) {