Merge "Handle race conditions in SCS when statsd dies" into rvc-dev am: 76994e73a7 (6a2d80e1) · Commits · e / os / android_frameworks_base

apex/statsd/service/java/com/android/server/stats/StatsCompanionService.java

+73 −86

Original line number	Diff line number	Diff line
		@@ -54,11 +54,11 @@ import java.io.FileDescriptor;
		import java.io.FileOutputStream;
		import java.io.IOException;
		import java.io.PrintWriter;
		import java.util.ArrayList;
		import java.util.HashMap;
		import java.util.HashSet;
		import java.util.List;
		import java.util.concurrent.TimeUnit;
		import java.util.concurrent.atomic.AtomicBoolean;

		/**
		* Helper service for statsd (the native stats management service in cmds/statsd/).
		@@ -112,17 +112,8 @@ public class StatsCompanionService extends IStatsCompanionService.Stub {
		private final HashMap<Long, String> mDeletedFiles = new HashMap<>();
		private final CompanionHandler mHandler;

		// Flag that is set when PHASE_BOOT_COMPLETED is triggered in the StatsCompanion lifecycle. This
		// and the flag mSentBootComplete below is used for synchronization to ensure that the boot
		// complete signal is only ever sent once to statsd. Two signals are needed because
		// #sayHiToStatsd can be called from both statsd and #onBootPhase
		// PHASE_THIRD_PARTY_APPS_CAN_START.
		@GuardedBy("sStatsdLock")
		private boolean mBootCompleted = false;
		// Flag that is set when IStatsd#bootCompleted is called. This flag ensures that boot complete
		// signal is only ever sent once.
		@GuardedBy("sStatsdLock")
		private boolean mSentBootComplete = false;
		// Flag that is set when PHASE_BOOT_COMPLETED is triggered in the StatsCompanion lifecycle.
		private AtomicBoolean mBootCompleted = new AtomicBoolean(false);

		public StatsCompanionService(Context context) {
		super();
		@@ -607,27 +598,35 @@ public class StatsCompanionService extends IStatsCompanionService.Stub {
		// Statsd related code

		/**
		* Fetches the statsd IBinder service. This is a blocking call.
		* Fetches the statsd IBinder service. This is a blocking call that always refetches statsd
		* instead of returning the cached sStatsd.
		* Note: This should only be called from {@link #sayHiToStatsd()}. All other clients should use
		* the cached sStatsd via {@link #getStatsdNonblocking()}.
		*/
		private IStatsd fetchStatsdService(StatsdDeathRecipient deathRecipient) {
		synchronized (sStatsdLock) {
		if (sStatsd == null) {
		private IStatsd fetchStatsdServiceLocked() {
		sStatsd = IStatsd.Stub.asInterface(StatsFrameworkInitializer
		.getStatsServiceManager()
		.getStatsdServiceRegisterer()
		.get());
		if (sStatsd != null) {
		return sStatsd;
		}

		private void registerStatsdDeathRecipient(IStatsd statsd, List<BroadcastReceiver> receivers) {
		StatsdDeathRecipient deathRecipient = new StatsdDeathRecipient(statsd, receivers);

		try {
		sStatsd.asBinder().linkToDeath(deathRecipient, /* flags */ 0);
		statsd.asBinder().linkToDeath(deathRecipient, /flags=/0);
		} catch (RemoteException e) {
		Log.e(TAG, "linkToDeath (StatsdDeathRecipient) failed");
		statsdNotReadyLocked();
		// Statsd has already died. Unregister receivers ourselves.
		for (BroadcastReceiver receiver : receivers) {
		mContext.unregisterReceiver(receiver);
		}
		synchronized (sStatsdLock) {
		if (statsd == sStatsd) {
		statsdNotReadyLocked();
		}
		}
		return sStatsd;
		}
		}

		@@ -648,22 +647,23 @@ public class StatsCompanionService extends IStatsCompanionService.Stub {
		* statsd.
		*/
		private void sayHiToStatsd() {
		if (getStatsdNonblocking() != null) {
		Log.e(TAG, "Trying to fetch statsd, but it was already fetched",
		new IllegalStateException(
		"sStatsd is not null when being fetched"));
		IStatsd statsd;
		synchronized (sStatsdLock) {
		if (sStatsd != null && sStatsd.asBinder().isBinderAlive()) {
		Log.e(TAG, "statsd has already been fetched before",
		new IllegalStateException("IStatsd object should be null or dead"));
		return;
		}
		StatsdDeathRecipient deathRecipient = new StatsdDeathRecipient();
		IStatsd statsd = fetchStatsdService(deathRecipient);
		statsd = fetchStatsdServiceLocked();
		}

		if (statsd == null) {
		Log.i(TAG,
		"Could not yet find statsd to tell it that StatsCompanion is "
		+ "alive.");
		Log.i(TAG, "Could not yet find statsd to tell it that StatsCompanion is alive.");
		return;
		}
		mStatsManagerService.statsdReady(statsd);

		if (DEBUG) Log.d(TAG, "Saying hi to statsd");
		mStatsManagerService.statsdReady(statsd);
		try {
		statsd.statsCompanionReady();

		@@ -682,8 +682,7 @@ public class StatsCompanionService extends IStatsCompanionService.Stub {
		mContext.registerReceiverForAllUsers(appUpdateReceiver, filter, null, null);

		// Setup receiver for user initialize (which happens once for a new user)
		// and
		// if a user is removed.
		// and if a user is removed.
		filter = new IntentFilter(Intent.ACTION_USER_INITIALIZE);
		filter.addAction(Intent.ACTION_USER_REMOVED);
		mContext.registerReceiverForAllUsers(userUpdateReceiver, filter, null, null);
		@@ -691,27 +690,20 @@ public class StatsCompanionService extends IStatsCompanionService.Stub {
		// Setup receiver for device reboots or shutdowns.
		filter = new IntentFilter(Intent.ACTION_REBOOT);
		filter.addAction(Intent.ACTION_SHUTDOWN);
		mContext.registerReceiverForAllUsers(
		shutdownEventReceiver, filter, null, null);
		mContext.registerReceiverForAllUsers(shutdownEventReceiver, filter, null, null);

		// Only add the receivers if the registration is successful.
		deathRecipient.addRegisteredBroadcastReceivers(
		List.of(appUpdateReceiver, userUpdateReceiver, shutdownEventReceiver));
		// Register death recipient.
		List<BroadcastReceiver> broadcastReceivers =
		List.of(appUpdateReceiver, userUpdateReceiver, shutdownEventReceiver);
		registerStatsdDeathRecipient(statsd, broadcastReceivers);

		// Used so we can call statsd.bootComplete() outside of the lock.
		boolean shouldSendBootComplete = false;
		synchronized (sStatsdLock) {
		if (mBootCompleted && !mSentBootComplete) {
		mSentBootComplete = true;
		shouldSendBootComplete = true;
		}
		}
		if (shouldSendBootComplete) {
		// Tell statsd that boot has completed. The signal may have already been sent, but since
		// the signal-receiving function is idempotent, that's ok.
		if (mBootCompleted.get()) {
		statsd.bootCompleted();
		}

		// Pull the latest state of UID->app name, version mapping when
		// statsd starts.
		// Pull the latest state of UID->app name, version mapping when statsd starts.
		informAllUids(mContext);

		Log.i(TAG, "Told statsd that StatsCompanionService is alive.");
		@@ -722,18 +714,16 @@ public class StatsCompanionService extends IStatsCompanionService.Stub {

		private class StatsdDeathRecipient implements IBinder.DeathRecipient {

		private List<BroadcastReceiver> mReceiversToUnregister;

		StatsdDeathRecipient() {
		mReceiversToUnregister = new ArrayList<>();
		}
		private final IStatsd mStatsd;
		private final List<BroadcastReceiver> mReceiversToUnregister;

		public void addRegisteredBroadcastReceivers(List<BroadcastReceiver> receivers) {
		synchronized (sStatsdLock) {
		mReceiversToUnregister.addAll(receivers);
		}
		StatsdDeathRecipient(IStatsd statsd, List<BroadcastReceiver> receivers) {
		mStatsd = statsd;
		mReceiversToUnregister = receivers;
		}

		// It is possible for binderDied to be called after a restarted statsd calls statsdReady,
		// but that's alright because the code does not assume an ordering of the two calls.
		@Override
		public void binderDied() {
		Log.i(TAG, "Statsd is dead - erase all my knowledge, except pullers");
		@@ -762,13 +752,19 @@ public class StatsCompanionService extends IStatsCompanionService.Stub {
		}
		}
		}
		// We only unregister in binder death becaseu receivers can only be unregistered
		// once, or an IllegalArgumentException is thrown.

		// Unregister receivers on death because receivers can only be unregistered once.
		// Otherwise, an IllegalArgumentException is thrown.
		for (BroadcastReceiver receiver: mReceiversToUnregister) {
		mContext.unregisterReceiver(receiver);
		}

		// It's possible for statsd to have restarted and called statsdReady, causing a new
		// sStatsd binder object to be fetched, before the binderDied callback runs. Only
		// call #statsdNotReadyLocked if that hasn't happened yet.
		if (mStatsd == sStatsd) {
		statsdNotReadyLocked();
		mSentBootComplete = false;
		}
		}
		}
		}
		@@ -779,20 +775,13 @@ public class StatsCompanionService extends IStatsCompanionService.Stub {
		}

		void bootCompleted() {
		mBootCompleted.set(true);
		IStatsd statsd = getStatsdNonblocking();
		synchronized (sStatsdLock) {
		mBootCompleted = true;
		if (mSentBootComplete) {
		// do not send a boot complete a second time.
		return;
		}
		if (statsd == null) {
		// Statsd is not yet ready.
		// Delay the boot completed ping to {@link #sayHiToStatsd()}
		return;
		}
		mSentBootComplete = true;
		}
		try {
		statsd.bootCompleted();
		} catch (RemoteException e) {
		@@ -808,8 +797,7 @@ public class StatsCompanionService extends IStatsCompanionService.Stub {
		}

		synchronized (sStatsdLock) {
		writer.println(
		"Number of configuration files deleted: " + mDeletedFiles.size());
		writer.println("Number of configuration files deleted: " + mDeletedFiles.size());
		if (mDeletedFiles.size() > 0) {
		writer.println(" timestamp, deleted file name");
		}
		@@ -817,8 +805,7 @@ public class StatsCompanionService extends IStatsCompanionService.Stub {
		SystemClock.currentThreadTimeMillis() - SystemClock.elapsedRealtime();
		for (Long elapsedMillis : mDeletedFiles.keySet()) {
		long deletionMillis = lastBootMillis + elapsedMillis;
		writer.println(
		" " + deletionMillis + ", " + mDeletedFiles.get(elapsedMillis));
		writer.println(" " + deletionMillis + ", " + mDeletedFiles.get(elapsedMillis));
		}
		}
		}

cmds/statsd/src/StatsService.cpp

+2 −0

Original line number	Diff line number	Diff line
		@@ -343,9 +343,11 @@ status_t StatsService::handleShellCommand(int in, int out, int err, const char**
		if (!utf8Args[0].compare(String8("print-logs"))) {
		return cmd_print_logs(out, utf8Args);
		}

		if (!utf8Args[0].compare(String8("send-active-configs"))) {
		return cmd_trigger_active_config_broadcast(out, utf8Args);
		}

		if (!utf8Args[0].compare(String8("data-subscribe"))) {
		{
		std::lock_guard<std::mutex> lock(mShellSubscriberMutex);