Throttle number of sound trigger operations / day
It is not clear when the day should start. Further a day might have
25 hours in the case of daylight savings time.
Hence a day in this case is the last 24 hours, not a calendar day.
Keeping track of the time of each operation might waste memory as we
don't need that much precision.
Hence keep track how many operations were performed in the last 24
hours in buckets of hours. If the total count reaches a maximum suppress
any further operations.
The maximum is configurable via global settings. It can be updated
by apps that have the appropriate permissions. Hence if the default
value turns out to be incorrect, it can be adjusted after release.
This does not throttle based on battery state as it is better to
completely unload the sound model to not even have a detection event.
Test: atest SoundTriggerDetectionServiceTests (separate CL)
atest android.provider.SettingsBackupTest
Bug: 73829108
Change-Id: Ied8570b60b61b6a055bd2576d1502c1b36424efa
diff --git a/services/voiceinteraction/java/com/android/server/soundtrigger/SoundTriggerService.java b/services/voiceinteraction/java/com/android/server/soundtrigger/SoundTriggerService.java
index f3ca6165..1160943 100644
--- a/services/voiceinteraction/java/com/android/server/soundtrigger/SoundTriggerService.java
+++ b/services/voiceinteraction/java/com/android/server/soundtrigger/SoundTriggerService.java
@@ -24,6 +24,7 @@
import static android.content.pm.PackageManager.MATCH_DEBUG_TRIAGED_MISSING;
import static android.hardware.soundtrigger.SoundTrigger.STATUS_ERROR;
import static android.hardware.soundtrigger.SoundTrigger.STATUS_OK;
+import static android.provider.Settings.Global.MAX_SOUND_TRIGGER_DETECTION_SERVICE_OPS_PER_DAY;
import static android.provider.Settings.Global.SOUND_TRIGGER_DETECTION_SERVICE_OP_TIMEOUT;
import static com.android.internal.util.function.pooled.PooledLambda.obtainMessage;
@@ -60,6 +61,7 @@
import android.os.RemoteException;
import android.os.UserHandle;
import android.provider.Settings;
+import android.util.ArrayMap;
import android.util.ArraySet;
import android.util.Slog;
@@ -72,9 +74,9 @@
import java.io.FileDescriptor;
import java.io.PrintWriter;
import java.util.ArrayList;
-import java.util.List;
import java.util.TreeMap;
import java.util.UUID;
+import java.util.concurrent.TimeUnit;
/**
* A single SystemService to manage all sound/voice-based sound models on the DSP.
@@ -100,6 +102,10 @@
private final TreeMap<UUID, IRecognitionStatusCallback> mCallbacks;
private PowerManager.WakeLock mWakelock;
+ /** Number of ops run by the {@link RemoteSoundTriggerDetectionService} per package name */
+ @GuardedBy("mLock")
+ private final ArrayMap<String, NumOps> mNumOpsPerPackage = new ArrayMap<>();
+
public SoundTriggerService(Context context) {
super(context);
mContext = context;
@@ -583,6 +589,71 @@
}
}
+ /**
+ * Counts the number of operations added in the last 24 hours.
+ */
+ private static class NumOps {
+ private final Object mLock = new Object();
+
+ @GuardedBy("mLock")
+ private int[] mNumOps = new int[24];
+ @GuardedBy("mLock")
+ private long mLastOpsHourSinceBoot;
+
+ /**
+ * Clear buckets of new hours that have elapsed since last operation.
+ *
+ * <p>I.e. when the last operation was triggered at 1:40 and the current operation was
+ * triggered at 4:03, the buckets "2, 3, and 4" are cleared.
+ *
+ * @param currentTime Current elapsed time since boot in ns
+ */
+ void clearOldOps(long currentTime) {
+ synchronized (mLock) {
+ long numHoursSinceBoot = TimeUnit.HOURS.convert(currentTime, TimeUnit.NANOSECONDS);
+
+ // Clear buckets of new hours that have elapsed since last operation
+ // I.e. when the last operation was triggered at 1:40 and the current
+ // operation was triggered at 4:03, the bucket "2, 3, and 4" is cleared
+ if (mLastOpsHourSinceBoot != 0) {
+ for (long hour = mLastOpsHourSinceBoot + 1; hour <= numHoursSinceBoot; hour++) {
+ mNumOps[(int) (hour % 24)] = 0;
+ }
+ }
+ }
+ }
+
+ /**
+ * Add a new operation.
+ *
+ * @param currentTime Current elapsed time since boot in ns
+ */
+ void addOp(long currentTime) {
+ synchronized (mLock) {
+ long numHoursSinceBoot = TimeUnit.HOURS.convert(currentTime, TimeUnit.NANOSECONDS);
+
+ mNumOps[(int) (numHoursSinceBoot % 24)]++;
+ mLastOpsHourSinceBoot = numHoursSinceBoot;
+ }
+ }
+
+ /**
+ * Get the total operations added in the last 24 hours.
+ *
+ * @return The total number of operations added in the last 24 hours
+ */
+ int getOpsAdded() {
+ synchronized (mLock) {
+ int totalOperationsInLastDay = 0;
+ for (int i = 0; i < 24; i++) {
+ totalOperationsInLastDay += mNumOps[i];
+ }
+
+ return totalOperationsInLastDay;
+ }
+ }
+ }
+
private interface Operation {
void run(int opId, ISoundTriggerDetectionService service) throws RemoteException;
}
@@ -625,6 +696,8 @@
/** Operations that have been send to the service but have no yet finished */
@GuardedBy("mRemoteServiceLock")
private final ArraySet<Integer> mRunningOpIds = new ArraySet<>();
+ /** The number of operations executed in each of the last 24 hours */
+ private final NumOps mNumOps;
/** The service binder if connected */
@GuardedBy("mRemoteServiceLock")
@@ -673,6 +746,15 @@
"RemoteSoundTriggerDetectionService " + mServiceName.getPackageName() + ":"
+ mServiceName.getClassName());
+ synchronized (mLock) {
+ NumOps numOps = mNumOpsPerPackage.get(mServiceName.getPackageName());
+ if (numOps == null) {
+ numOps = new NumOps();
+ mNumOpsPerPackage.put(mServiceName.getPackageName(), numOps);
+ }
+ mNumOps = numOps;
+ }
+
mClient = new ISoundTriggerDetectionServiceClient.Stub() {
@Override
public void onOpFinished(int opId) {
@@ -830,6 +912,25 @@
bind();
}
} else {
+ long currentTime = System.nanoTime();
+ mNumOps.clearOldOps(currentTime);
+
+ // Drop operation if too many were executed in the last 24 hours.
+ int opsAllowed = Settings.Global.getInt(mContext.getContentResolver(),
+ MAX_SOUND_TRIGGER_DETECTION_SERVICE_OPS_PER_DAY,
+ Integer.MAX_VALUE);
+
+ int opsAdded = mNumOps.getOpsAdded();
+ if (mNumOps.getOpsAdded() >= opsAllowed) {
+ if (DEBUG || opsAllowed + 10 > opsAdded) {
+ Slog.w(TAG, mPuuid + ": Dropped operation as too many operations were "
+ + "run in last 24 hours");
+ }
+ return;
+ }
+
+ mNumOps.addOp(currentTime);
+
// Find a free opID
int opId = mNumTotalOpsPerformed;
do {