Merge "[SP17] Wait for stats providers to report stats update"
diff --git a/services/core/java/com/android/server/net/NetworkStatsService.java b/services/core/java/com/android/server/net/NetworkStatsService.java
index 415ccb8..1c52110 100644
--- a/services/core/java/com/android/server/net/NetworkStatsService.java
+++ b/services/core/java/com/android/server/net/NetworkStatsService.java
@@ -155,6 +155,8 @@
import java.util.HashSet;
import java.util.List;
import java.util.Objects;
+import java.util.concurrent.Semaphore;
+import java.util.concurrent.TimeUnit;
/**
* Collect and persist detailed network statistics, and provide this data to
@@ -280,8 +282,11 @@
private final DropBoxNonMonotonicObserver mNonMonotonicObserver =
new DropBoxNonMonotonicObserver();
+ private static final int MAX_STATS_PROVIDER_POLL_WAIT_TIME_MS = 100;
private final RemoteCallbackList<NetworkStatsProviderCallbackImpl> mStatsProviderCbList =
new RemoteCallbackList<>();
+ /** Semaphore used to wait for stats provider to respond to request stats update. */
+ private final Semaphore mStatsProviderSem = new Semaphore(0, true);
@GuardedBy("mStatsLock")
private NetworkStatsRecorder mDevRecorder;
@@ -1337,6 +1342,25 @@
final boolean persistUid = (flags & FLAG_PERSIST_UID) != 0;
final boolean persistForce = (flags & FLAG_PERSIST_FORCE) != 0;
+ // Request asynchronous stats update from all providers for next poll. And wait a bit of
+ // time to allow providers report-in given that normally binder call should be fast.
+ // TODO: request with a valid token.
+ Trace.traceBegin(TRACE_TAG_NETWORK, "provider.requestStatsUpdate");
+ final int registeredCallbackCount = mStatsProviderCbList.getRegisteredCallbackCount();
+ mStatsProviderSem.drainPermits();
+ invokeForAllStatsProviderCallbacks((cb) -> cb.mProvider.requestStatsUpdate(0 /* unused */));
+ try {
+ mStatsProviderSem.tryAcquire(registeredCallbackCount,
+ MAX_STATS_PROVIDER_POLL_WAIT_TIME_MS, TimeUnit.MILLISECONDS);
+ } catch (InterruptedException e) {
+ // Strictly speaking it's possible a provider happened to deliver between the timeout
+ // and the log, and that doesn't matter too much as this is just a debug log.
+ Log.d(TAG, "requestStatsUpdate - providers responded "
+ + mStatsProviderSem.availablePermits()
+ + "/" + registeredCallbackCount + " : " + e);
+ }
+ Trace.traceEnd(TRACE_TAG_NETWORK);
+
// TODO: consider marking "untrusted" times in historical stats
final long currentTime = mClock.millis();
@@ -1374,10 +1398,6 @@
performSampleLocked();
}
- // request asynchronous stats update from all providers for next poll.
- // TODO: request with a valid token.
- invokeForAllStatsProviderCallbacks((cb) -> cb.mProvider.requestStatsUpdate(0 /* unused */));
-
// finally, dispatch updated event to any listeners
final Intent updatedIntent = new Intent(ACTION_NETWORK_STATS_UPDATED);
updatedIntent.setFlags(Intent.FLAG_RECEIVER_REGISTERED_ONLY);
@@ -1798,7 +1818,8 @@
Objects.requireNonNull(tag, "tag is null");
try {
NetworkStatsProviderCallbackImpl callback = new NetworkStatsProviderCallbackImpl(
- tag, provider, mAlertObserver, mStatsProviderCbList);
+ tag, provider, mStatsProviderSem, mAlertObserver,
+ mStatsProviderCbList);
mStatsProviderCbList.register(callback);
Log.d(TAG, "registerNetworkStatsProvider from " + callback.mTag + " uid/pid="
+ getCallingUid() + "/" + getCallingPid());
@@ -1846,6 +1867,7 @@
@NonNull final String mTag;
@NonNull private final Object mProviderStatsLock = new Object();
@NonNull final INetworkStatsProvider mProvider;
+ @NonNull private final Semaphore mSemaphore;
@NonNull final INetworkManagementEventObserver mAlertObserver;
@NonNull final RemoteCallbackList<NetworkStatsProviderCallbackImpl> mStatsProviderCbList;
@@ -1857,12 +1879,14 @@
NetworkStatsProviderCallbackImpl(
@NonNull String tag, @NonNull INetworkStatsProvider provider,
+ @NonNull Semaphore semaphore,
@NonNull INetworkManagementEventObserver alertObserver,
@NonNull RemoteCallbackList<NetworkStatsProviderCallbackImpl> cbList)
throws RemoteException {
mTag = tag;
mProvider = provider;
mProvider.asBinder().linkToDeath(this, 0);
+ mSemaphore = semaphore;
mAlertObserver = alertObserver;
mStatsProviderCbList = cbList;
}
@@ -1895,6 +1919,7 @@
if (ifaceStats != null) mIfaceStats.combineAllValues(ifaceStats);
if (uidStats != null) mUidStats.combineAllValues(uidStats);
}
+ mSemaphore.release();
}
@Override