Remove calls to client while holding lock (71535717) · Commits · e / os / android_frameworks_base

services/core/java/com/android/server/audio/PlaybackActivityMonitor.java

+85 −74

Original line number	Diff line number	Diff line
		@@ -49,6 +49,7 @@ import java.util.HashMap;
		import java.util.Iterator;
		import java.util.List;
		import java.util.Set;
		import java.util.concurrent.ConcurrentLinkedQueue;
		import java.util.function.Consumer;

		/**
		@@ -104,11 +105,7 @@ public final class PlaybackActivityMonitor
		private static final VolumeShaper.Operation PLAY_SKIP_RAMP =
		new VolumeShaper.Operation.Builder(PLAY_CREATE_IF_NEEDED).setXOffset(1.0f).build();

		private final ArrayList<PlayMonitorClient> mClients = new ArrayList<PlayMonitorClient>();
		// a public client is one that needs an anonymized version of the playback configurations, we
		// keep track of whether there is at least one to know when we need to create the list of
		// playback configurations that do not contain uid/pid/package name information.
		private boolean mHasPublicClients = false;
		private final ConcurrentLinkedQueue<PlayMonitorClient> mClients = new ConcurrentLinkedQueue<>();

		private final Object mPlayerLock = new Object();
		@GuardedBy("mPlayerLock")
		@@ -458,12 +455,10 @@ public final class PlaybackActivityMonitor
		+ DateFormat.getTimeInstance().format(new Date()));
		synchronized(mPlayerLock) {
		pw.println("\n playback listeners:");
		synchronized(mClients) {
		for (PlayMonitorClient pmc : mClients) {
		pw.print(" " + (pmc.mIsPrivileged ? "(S)" : "(P)")
		pw.print(" " + (pmc.isPrivileged() ? "(S)" : "(P)")
		+ pmc.toString());
		}
		}
		pw.println("\n");
		// all players
		pw.println("\n players:");
		@@ -534,48 +529,33 @@ public final class PlaybackActivityMonitor
		* @param iplayerReleased indicates if the change was due to a player being released
		*/
		private void dispatchPlaybackChange(boolean iplayerReleased) {
		synchronized (mClients) {
		// typical use case, nobody is listening, don't do any work
		if (mClients.isEmpty()) {
		return;
		}
		}
		if (DEBUG) { Log.v(TAG, "dispatchPlaybackChange to " + mClients.size() + " clients"); }
		final List<AudioPlaybackConfiguration> configsSystem;
		// list of playback configurations for "public consumption". It is only computed if there
		// list of playback configurations for "public consumption". It is computed lazy if there
		// are non-system playback activity listeners.
		final List<AudioPlaybackConfiguration> configsPublic;
		List<AudioPlaybackConfiguration> configsPublic = null;
		synchronized (mPlayerLock) {
		if (mPlayers.isEmpty()) {
		return;
		}
		configsSystem = new ArrayList<AudioPlaybackConfiguration>(mPlayers.values());
		configsSystem = new ArrayList<>(mPlayers.values());
		}
		synchronized (mClients) {
		// was done at beginning of method, but could have changed
		if (mClients.isEmpty()) {
		return;
		}
		configsPublic = mHasPublicClients ? anonymizeForPublicConsumption(configsSystem) : null;

		final Iterator<PlayMonitorClient> clientIterator = mClients.iterator();
		while (clientIterator.hasNext()) {
		final PlayMonitorClient pmc = clientIterator.next();
		try {
		// do not spam the logs if there are problems communicating with this client
		if (pmc.mErrorCount < PlayMonitorClient.MAX_ERRORS) {
		if (pmc.mIsPrivileged) {
		pmc.mDispatcherCb.dispatchPlaybackConfigChange(configsSystem,
		if (!pmc.reachedMaxErrorCount()) {
		if (pmc.isPrivileged()) {
		pmc.dispatchPlaybackConfigChange(configsSystem,
		iplayerReleased);
		} else {
		if (configsPublic == null) {
		configsPublic = anonymizeForPublicConsumption(configsSystem);
		}
		// non-system clients don't have the control interface IPlayer, so
		// they don't need to flush commands when a player was released
		pmc.mDispatcherCb.dispatchPlaybackConfigChange(configsPublic, false);
		}
		}
		} catch (RemoteException e) {
		pmc.mErrorCount++;
		Log.e(TAG, "Error (" + pmc.mErrorCount +
		") trying to dispatch playback config change to " + pmc, e);
		pmc.dispatchPlaybackConfigChange(configsPublic, false);
		}
		}
		}
		@@ -798,40 +778,26 @@ public final class PlaybackActivityMonitor
		if (pcdb == null) {
		return;
		}
		synchronized(mClients) {
		final PlayMonitorClient pmc = new PlayMonitorClient(pcdb, isPrivileged);
		if (pmc.init()) {
		if (!isPrivileged) {
		mHasPublicClients = true;
		}
		mClients.add(pmc);
		}
		}
		}

		void unregisterPlaybackCallback(IPlaybackConfigDispatcher pcdb) {
		if (pcdb == null) {
		return;
		}
		synchronized(mClients) {
		final Iterator<PlayMonitorClient> clientIterator = mClients.iterator();
		boolean hasPublicClients = false;
		// iterate over the clients to remove the dispatcher to remove, and reevaluate at
		// the same time if we still have a public client.
		// iterate over the clients to remove the dispatcher
		while (clientIterator.hasNext()) {
		PlayMonitorClient pmc = clientIterator.next();
		if (pcdb.asBinder().equals(pmc.mDispatcherCb.asBinder())) {
		if (pmc.equalsDispatcher(pcdb)) {
		pmc.release();
		clientIterator.remove();
		} else {
		if (!pmc.mIsPrivileged) {
		hasPublicClients = true;
		}
		}
		}
		mHasPublicClients = hasPublicClients;
		}
		}

		List<AudioPlaybackConfiguration> getActivePlaybackConfigurations(boolean isPrivileged) {
		synchronized(mPlayers) {
		@@ -857,24 +823,34 @@ public final class PlaybackActivityMonitor
		// can afford to be static because only one PlaybackActivityMonitor ever instantiated
		static PlaybackActivityMonitor sListenerDeathMonitor;

		final IPlaybackConfigDispatcher mDispatcherCb;
		final boolean mIsPrivileged;

		int mErrorCount = 0;
		// number of errors after which we don't update this client anymore to not spam the logs
		static final int MAX_ERRORS = 5;
		private static final int MAX_ERRORS = 5;

		private final IPlaybackConfigDispatcher mDispatcherCb;

		@GuardedBy("this")
		private final boolean mIsPrivileged;
		@GuardedBy("this")
		private boolean mIsReleased = false;
		@GuardedBy("this")
		private int mErrorCount = 0;

		PlayMonitorClient(IPlaybackConfigDispatcher pcdb, boolean isPrivileged) {
		mDispatcherCb = pcdb;
		mIsPrivileged = isPrivileged;
		}

		@Override
		public void binderDied() {
		Log.w(TAG, "client died");
		sListenerDeathMonitor.unregisterPlaybackCallback(mDispatcherCb);
		}

		boolean init() {
		synchronized boolean init() {
		if (mIsReleased) {
		// Do not init after release
		return false;
		}
		try {
		mDispatcherCb.asBinder().linkToDeath(this, 0);
		return true;
		@@ -884,8 +860,43 @@ public final class PlaybackActivityMonitor
		}
		}

		void release() {
		synchronized void release() {
		mDispatcherCb.asBinder().unlinkToDeath(this, 0);
		mIsReleased = true;
		}

		void dispatchPlaybackConfigChange(List<AudioPlaybackConfiguration> configs,
		boolean flush) {
		synchronized (this) {
		if (mIsReleased) {
		// Do not dispatch anything after release
		return;
		}
		}
		try {
		mDispatcherCb.dispatchPlaybackConfigChange(configs, flush);
		} catch (RemoteException e) {
		synchronized (this) {
		mErrorCount++;
		Log.e(TAG, "Error (" + mErrorCount
		+ ") trying to dispatch playback config change to " + this, e);
		}
		}
		}

		synchronized boolean isPrivileged() {
		return mIsPrivileged;
		}

		synchronized boolean reachedMaxErrorCount() {
		return mErrorCount >= MAX_ERRORS;
		}

		synchronized boolean equalsDispatcher(IPlaybackConfigDispatcher pcdb) {
		if (pcdb == null) {
		return false;
		}
		return pcdb.asBinder().equals(mDispatcherCb.asBinder());
		}
		}