diff options
| -rw-r--r-- | services/core/java/com/android/server/audio/AudioService.java | 83 |
1 files changed, 45 insertions, 38 deletions
diff --git a/services/core/java/com/android/server/audio/AudioService.java b/services/core/java/com/android/server/audio/AudioService.java index b738482ba66c..168ec052e67d 100644 --- a/services/core/java/com/android/server/audio/AudioService.java +++ b/services/core/java/com/android/server/audio/AudioService.java @@ -790,8 +790,7 @@ public class AudioService extends IAudioService.Stub private final BroadcastReceiver mReceiver = new AudioServiceBroadcastReceiver(); private final Executor mAudioServerLifecycleExecutor; - private final ConcurrentLinkedQueue<Future> mScheduledPermissionTasks = - new ConcurrentLinkedQueue(); + private final List<Future> mScheduledPermissionTasks = new ArrayList(); private IMediaProjectionManager mProjectionService; // to validate projection token @@ -10600,46 +10599,50 @@ public class AudioService extends IAudioService.Stub // instanceof to simplify the construction requirements of AudioService for testing: no // delayed execution during unit tests. if (mAudioServerLifecycleExecutor instanceof ScheduledExecutorService exec) { - // We schedule and add from a this callback thread only (serially), so the task order on - // the serial executor matches the order on the task list. This list should almost - // always have only two elements, except in cases of serious system contention. - Runnable task = () -> mScheduledPermissionTasks.add(exec.schedule(() -> { - try { - // Clean up completed tasks before us to bound the queue length. Cancel any - // pending permission refresh tasks, after our own, since we are about to - // fulfill all of them. We must be the first non-completed task in the - // queue, since the execution order matches the queue order. Note, this - // task is the only writer on elements in the queue, and the task is - // serialized, so - // => no in-flight cancellation - // => exists at least one non-completed task (ourselves) - // => the queue is non-empty (only completed tasks removed) - final var iter = mScheduledPermissionTasks.iterator(); - while (iter.next().isDone()) { - iter.remove(); - } - // iter is on the first element which is not completed (us) - while (iter.hasNext()) { - if (!iter.next().cancel(false)) { - throw new AssertionError( - "Cancel should be infallible since we" + - "cancel from the executor"); + // The order on the task list is an embedding on the scheduling order of the executor, + // since we synchronously add the scheduled task to our local queue. This list should + // almost always have only two elements, except in cases of serious system contention. + Runnable task = () -> { + synchronized (mScheduledPermissionTasks) { + mScheduledPermissionTasks.add(exec.schedule(() -> { + try { + // Our goal is to remove all tasks which don't correspond to ourselves + // on this queue. Either they are already done (ahead of us), or we + // should cancel them (behind us), since their work is redundant after + // we fire. + // We must be the first non-completed task in the queue, since the + // execution order matches the queue order. Note, this task is the only + // writer on elements in the queue, and the task is serialized, so + // => no in-flight cancellation + // => exists at least one non-completed task (ourselves) + // => the queue is non-empty (only completed tasks removed) + synchronized (mScheduledPermissionTasks) { + final var iter = mScheduledPermissionTasks.iterator(); + while (iter.next().isDone()) { + iter.remove(); + } + // iter is on the first element which is not completed (us) + while (iter.hasNext()) { + if (!iter.next().cancel(false)) { + throw new AssertionError( + "Cancel should be infallible since we" + + "cancel from the executor"); + } + iter.remove(); + } } - iter.remove(); + mPermissionProvider.onPermissionStateChanged(); + } catch (Exception e) { + // Handle executor routing exceptions to nowhere + Thread.getDefaultUncaughtExceptionHandler() + .uncaughtException(Thread.currentThread(), e); } - mPermissionProvider.onPermissionStateChanged(); - } catch (Exception e) { - // Handle executor routing exceptions to nowhere - Thread.getDefaultUncaughtExceptionHandler() - .uncaughtException(Thread.currentThread(), e); - } - }, - UPDATE_DELAY_MS, - TimeUnit.MILLISECONDS)); + }, UPDATE_DELAY_MS, TimeUnit.MILLISECONDS)); + } + }; mAudioSystem.listenForSystemPropertyChange( PermissionManager.CACHE_KEY_PACKAGE_INFO, task); - task.run(); } else { mAudioSystem.listenForSystemPropertyChange( PermissionManager.CACHE_KEY_PACKAGE_INFO, @@ -14710,7 +14713,11 @@ public class AudioService extends IAudioService.Stub @Override /** @see AudioManager#permissionUpdateBarrier() */ public void permissionUpdateBarrier() { - for (var x : List.copyOf(mScheduledPermissionTasks)) { + List<Future> snapshot; + synchronized (mScheduledPermissionTasks) { + snapshot = List.copyOf(mScheduledPermissionTasks); + } + for (var x : snapshot) { try { x.get(); } catch (CancellationException e) { |