Support batched requests < GNSS batched size
Use an alarm to manually flush GNSS location batches if the batch size
is less than the GNSS batch size.
Test: manual
Bug: 190054044
Change-Id: Ib93f534bb0610aee2310c5d72a226850741cbe58
diff --git a/services/core/java/com/android/server/location/gnss/GnssLocationProvider.java b/services/core/java/com/android/server/location/gnss/GnssLocationProvider.java
index f3dcfbb..9956da2 100644
--- a/services/core/java/com/android/server/location/gnss/GnssLocationProvider.java
+++ b/services/core/java/com/android/server/location/gnss/GnssLocationProvider.java
@@ -16,6 +16,7 @@
package com.android.server.location.gnss;
+import static android.app.AlarmManager.ELAPSED_REALTIME_WAKEUP;
import static android.location.provider.ProviderProperties.ACCURACY_FINE;
import static android.location.provider.ProviderProperties.POWER_USAGE_HIGH;
@@ -43,6 +44,8 @@
import static com.android.server.location.gnss.hal.GnssNative.GNSS_POSITION_MODE_STANDALONE;
import static com.android.server.location.gnss.hal.GnssNative.GNSS_POSITION_RECURRENCE_PERIODIC;
+import static java.lang.Math.abs;
+import static java.lang.Math.max;
import static java.util.concurrent.TimeUnit.MILLISECONDS;
import android.app.AlarmManager;
@@ -85,6 +88,7 @@
import android.telephony.TelephonyManager;
import android.telephony.gsm.GsmCellLocation;
import android.text.TextUtils;
+import android.text.format.DateUtils;
import android.util.Log;
import android.util.TimeUtils;
@@ -103,7 +107,9 @@
import java.io.FileDescriptor;
import java.io.PrintWriter;
import java.util.ArrayList;
+import java.util.Arrays;
import java.util.Collections;
+import java.util.Comparator;
import java.util.HashSet;
import java.util.List;
import java.util.Objects;
@@ -156,6 +162,10 @@
private static final long LOCATION_UPDATE_DURATION_MILLIS = 10 * 1000;
// Update duration extension multiplier for emergency REQUEST_LOCATION.
private static final int EMERGENCY_LOCATION_UPDATE_DURATION_MULTIPLIER = 3;
+ // maximum length gnss batching may go for (1 day)
+ private static final int MIN_BATCH_INTERVAL_MS = (int) DateUtils.SECOND_IN_MILLIS;
+ private static final long MAX_BATCH_LENGTH_MS = DateUtils.DAY_IN_MILLIS;
+ private static final long MAX_BATCH_TIMESTAMP_DELTA_MS = 500;
// Threadsafe class to hold stats reported in the Extras Bundle
private static class LocationExtras {
@@ -245,6 +255,7 @@
private boolean mShutdown;
private boolean mStarted;
private boolean mBatchingStarted;
+ private AlarmManager.OnAlarmListener mBatchingAlarm;
private long mStartedChangedElapsedRealtime;
private int mFixInterval = 1000;
@@ -845,18 +856,15 @@
mFixInterval = Integer.MAX_VALUE;
}
- // requested batch size, or zero to disable batching
- long batchSize =
- mBatchingEnabled ? mProviderRequest.getMaxUpdateDelayMillis() / Math.max(
- mFixInterval, 1) : 0;
- if (batchSize < getBatchSize()) {
- batchSize = 0;
- }
+ int batchIntervalMs = max(mFixInterval, MIN_BATCH_INTERVAL_MS);
+ long batchLengthMs = Math.min(mProviderRequest.getMaxUpdateDelayMillis(),
+ MAX_BATCH_LENGTH_MS);
// apply request to GPS engine
- if (batchSize > 0) {
+ if (mBatchingEnabled && batchLengthMs / 2 >= batchIntervalMs) {
stopNavigating();
- startBatching();
+ mFixInterval = batchIntervalMs;
+ startBatching(batchLengthMs);
} else {
stopBatching();
@@ -875,7 +883,7 @@
if (mFixInterval >= NO_FIX_TIMEOUT) {
// set timer to give up if we do not receive a fix within NO_FIX_TIMEOUT
// and our fix interval is not short
- mAlarmManager.set(AlarmManager.ELAPSED_REALTIME_WAKEUP,
+ mAlarmManager.set(ELAPSED_REALTIME_WAKEUP,
SystemClock.elapsedRealtime() + NO_FIX_TIMEOUT, TAG,
mTimeoutListener, mHandler);
}
@@ -1066,7 +1074,7 @@
// set timer to give up if we do not receive a fix within NO_FIX_TIMEOUT
// and our fix interval is not short
if (mFixInterval >= NO_FIX_TIMEOUT) {
- mAlarmManager.set(AlarmManager.ELAPSED_REALTIME_WAKEUP,
+ mAlarmManager.set(ELAPSED_REALTIME_WAKEUP,
SystemClock.elapsedRealtime() + NO_FIX_TIMEOUT, TAG, mTimeoutListener,
mHandler);
}
@@ -1090,12 +1098,37 @@
mAlarmManager.cancel(mWakeupListener);
}
- private void startBatching() {
+ private void startBatching(long batchLengthMs) {
+ long batchSize = batchLengthMs / mFixInterval;
+
if (DEBUG) {
- Log.d(TAG, "startBatching " + mFixInterval);
+ Log.d(TAG, "startBatching " + mFixInterval + " " + batchLengthMs);
}
if (mGnssNative.startBatch(MILLISECONDS.toNanos(mFixInterval), true)) {
mBatchingStarted = true;
+
+ if (batchSize < getBatchSize()) {
+ // if the batch size is smaller than the hardware batch size, use an alarm to flush
+ // locations as appropriate
+ mBatchingAlarm = () -> {
+ boolean flush = false;
+ synchronized (mLock) {
+ if (mBatchingAlarm != null) {
+ flush = true;
+ mAlarmManager.setExact(ELAPSED_REALTIME_WAKEUP,
+ SystemClock.elapsedRealtime() + batchLengthMs, TAG,
+ mBatchingAlarm, FgThread.getHandler());
+ }
+ }
+
+ if (flush) {
+ mGnssNative.flushBatch();
+ }
+ };
+ mAlarmManager.setExact(ELAPSED_REALTIME_WAKEUP,
+ SystemClock.elapsedRealtime() + batchLengthMs, TAG,
+ mBatchingAlarm, FgThread.getHandler());
+ }
} else {
Log.e(TAG, "native_start_batch failed in startBatching()");
}
@@ -1104,6 +1137,10 @@
private void stopBatching() {
if (DEBUG) Log.d(TAG, "stopBatching");
if (mBatchingStarted) {
+ if (mBatchingAlarm != null) {
+ mAlarmManager.cancel(mBatchingAlarm);
+ mBatchingAlarm = null;
+ }
mGnssNative.stopBatch();
mBatchingStarted = false;
}
@@ -1120,7 +1157,7 @@
// stop GPS until our next fix interval arrives
stopNavigating();
long now = SystemClock.elapsedRealtime();
- mAlarmManager.set(AlarmManager.ELAPSED_REALTIME_WAKEUP, now + mFixInterval, TAG,
+ mAlarmManager.set(ELAPSED_REALTIME_WAKEUP, now + mFixInterval, TAG,
mWakeupListener, mHandler);
}
@@ -1485,16 +1522,50 @@
Log.d(TAG, "Location batch of size " + locations.length + " reported");
}
+ if (locations.length > 0) {
+ // attempt to fix up timestamps if necessary
+ if (locations.length > 1) {
+ // check any realtimes outside of expected bounds
+ boolean fixRealtime = false;
+ for (int i = locations.length - 2; i >= 0; i--) {
+ long timeDeltaMs = locations[i + 1].getTime() - locations[i].getTime();
+ long realtimeDeltaMs = locations[i + 1].getElapsedRealtimeMillis()
+ - locations[i].getElapsedRealtimeMillis();
+ if (abs(timeDeltaMs - realtimeDeltaMs) > MAX_BATCH_TIMESTAMP_DELTA_MS) {
+ fixRealtime = true;
+ break;
+ }
+ }
+
+ if (fixRealtime) {
+ // sort for monotonically increasing time before fixing realtime - realtime will
+ // thus also be monotonically increasing
+ Arrays.sort(locations,
+ Comparator.comparingLong(Location::getTime));
+
+ long expectedDeltaMs =
+ locations[locations.length - 1].getTime()
+ - locations[locations.length - 1].getElapsedRealtimeMillis();
+ for (int i = locations.length - 2; i >= 0; i--) {
+ locations[i].setElapsedRealtimeNanos(
+ MILLISECONDS.toNanos(
+ max(locations[i].getTime() - expectedDeltaMs, 0)));
+ }
+ } else {
+ // sort for monotonically increasing realttime
+ Arrays.sort(locations,
+ Comparator.comparingLong(Location::getElapsedRealtimeNanos));
+ }
+ }
+
+ reportLocation(LocationResult.wrap(locations).validate());
+ }
+
Runnable[] listeners;
synchronized (mLock) {
listeners = mFlushListeners.toArray(new Runnable[0]);
mFlushListeners.clear();
}
-
- if (locations.length > 0) {
- reportLocation(LocationResult.wrap(locations).validate());
- }
-
for (Runnable listener : listeners) {
listener.run();
}