Update isInEmergency without holding a lock (39275e7d) · Commits · e / os / android_frameworks_base

location/java/android/location/flags/location.aconfig

+10 −0

Original line number	Diff line number	Diff line
		@@ -166,6 +166,16 @@ flag {
		}
		}

		flag {
		name: "update_is_in_emergency_before_on_register"
		namespace: "location"
		description: "Update isInEmergency before onRegister() without holding a lock"
		bug: "355384257"
		metadata {
		purpose: PURPOSE_BUGFIX
		}
		}

		flag {
		name: "gnss_assistance_interface_jni"
		namespace: "location"

services/core/java/com/android/server/location/provider/LocationProviderManager.java

+42 −25

Original line number	Diff line number	Diff line
		@@ -395,6 +395,9 @@ public class LocationProviderManager extends
		@GuardedBy("mMultiplexerLock")
		private boolean mIsUsingHighPower;

		@GuardedBy("mMultiplexerLock")
		private boolean mIsInEmergency;

		@Nullable private Location mLastLocation = null;

		protected Registration(LocationRequest request, CallerIdentity identity, Executor executor,
		@@ -421,6 +424,24 @@ public class LocationProviderManager extends
		}
		}

		/ Update {@link #mIsInEmergency} by invoking Telephony APIs. /
		public void updateIsInEmergency() {
		boolean isInEmergency = mEmergencyHelper.isInEmergency(0);
		synchronized (mMultiplexerLock) {
		mIsInEmergency = isInEmergency;
		}
		}

		/**
		* Make sure to call {@link #updateIsInEmergency()} before calling this method to keep
		* {@link #mIsInEmergency} up-to-date.
		*
		* <p>See b/426562854 for more details. {@link #updateIsInEmergency()} is a short term
		* solution to avoid calling IPC with a lock by caching the state right before onRegister().
		* The long term solution should be avoiding any synchronous
		* {@link EmergencyHelper#isInEmergency()}} and using the asynchronous emergency listeners
		* instead.
		*/
		@GuardedBy("mMultiplexerLock")
		@Override
		protected void onRegister() {
		@@ -435,7 +456,11 @@ public class LocationProviderManager extends

		// initialization order is important as there are ordering dependencies
		onLocationPermissionsChanged();
		if (Flags.updateIsInEmergencyBeforeOnRegister()) {
		onBypassLocationPermissionsChanged(mIsInEmergency);
		} else {
		onBypassLocationPermissionsChanged(mEmergencyHelper.isInEmergency(0));
		}
		mForeground = mAppForegroundHelper.isAppForeground(getIdentity().getUid());
		mProviderLocationRequest = calculateProviderLocationRequest();
		mIsUsingHighPower = isUsingHighPower();
		@@ -1991,20 +2016,12 @@ public class LocationProviderManager extends
		identity,
		new GetCurrentLocationTransport(callback),
		permissionLevel);

		synchronized (mMultiplexerLock) {
		Preconditions.checkState(mState != STATE_STOPPED);
		final long ident = Binder.clearCallingIdentity();
		try {
		putRegistration(callback.asBinder(), registration);
		registerAndHandleIdentity(callback.asBinder(), registration, () -> {
		if (!registration.isActive()) {
		// if the registration never activated, fail it immediately
		registration.deliverNull();
		}
		} finally {
		Binder.restoreCallingIdentity(ident);
		}
		}
		});

		ICancellationSignal cancelTransport = CancellationSignal.createTransport();
		CancellationSignal.fromTransport(cancelTransport)
		@@ -2045,16 +2062,7 @@ public class LocationProviderManager extends
		identity,
		new LocationListenerTransport(listener),
		permissionLevel);

		synchronized (mMultiplexerLock) {
		Preconditions.checkState(mState != STATE_STOPPED);
		final long ident = Binder.clearCallingIdentity();
		try {
		putRegistration(listener.asBinder(), registration);
		} finally {
		Binder.restoreCallingIdentity(ident);
		}
		}
		registerAndHandleIdentity(listener.asBinder(), registration, () -> {});
		}

		public void registerLocationRequest(LocationRequest request, CallerIdentity callerIdentity,
		@@ -2064,12 +2072,21 @@ public class LocationProviderManager extends
		callerIdentity,
		new LocationPendingIntentTransport(mContext, pendingIntent),
		permissionLevel);
		registerAndHandleIdentity(pendingIntent, registration, () -> {});
		}

		private <T> void registerAndHandleIdentity(T key, Registration registration,
		Runnable postRegistrationRunnable) {
		if (Flags.updateIsInEmergencyBeforeOnRegister()) {
		registration.updateIsInEmergency();
		}

		synchronized (mMultiplexerLock) {
		Preconditions.checkState(mState != STATE_STOPPED);
		final long identity = Binder.clearCallingIdentity();
		try {
		putRegistration(pendingIntent, registration);
		putRegistration(key, registration);
		postRegistrationRunnable.run();
		} finally {
		Binder.restoreCallingIdentity(identity);
		}