Merge "Ask netd to swap stats map before reading" (e13a14d5) · Commits · e / os / android_frameworks_base

services/core/java/com/android/server/net/NetworkStatsFactory.java

+25 −0

Original line number	Diff line number	Diff line
		@@ -24,7 +24,10 @@ import static android.net.NetworkStats.UID_ALL;
		import static com.android.server.NetworkManagementSocketTagger.kernelToTag;

		import android.annotation.Nullable;
		import android.net.INetd;
		import android.net.NetworkStats;
		import android.net.util.NetdService;
		import android.os.RemoteException;
		import android.os.StrictMode;
		import android.os.SystemClock;

		@@ -65,6 +68,8 @@ public class NetworkStatsFactory {

		private boolean mUseBpfStats;

		private INetd mNetdService;

		// A persistent Snapshot since device start for eBPF stats
		@GuardedBy("mPersistSnapshot")
		private final NetworkStats mPersistSnapshot;
		@@ -279,6 +284,19 @@ public class NetworkStatsFactory {
		return stats;
		}

		@GuardedBy("mPersistSnapshot")
		private void requestSwapActiveStatsMapLocked() throws RemoteException {
		// Ask netd to do a active map stats swap. When the binder call successfully returns,
		// the system server should be able to safely read and clean the inactive map
		// without race problem.
		if (mUseBpfStats) {
		if (mNetdService == null) {
		mNetdService = NetdService.getInstance();
		}
		mNetdService.trafficSwapActiveStatsMap();
		}
		}

		// TODO: delete the lastStats parameter
		private NetworkStats readNetworkStatsDetailInternal(int limitUid, String[] limitIfaces,
		int limitTag, NetworkStats lastStats) throws IOException {
		@@ -292,6 +310,13 @@ public class NetworkStatsFactory {
		}
		if (mUseBpfStats) {
		synchronized (mPersistSnapshot) {
		try {
		requestSwapActiveStatsMapLocked();
		} catch (RemoteException e) {
		throw new IOException(e);
		}
		// Stats are always read from the inactive map, so they must be read after the
		// swap
		if (nativeReadNetworkStatsDetail(stats, mStatsXtUid.getAbsolutePath(), UID_ALL,
		null, TAG_ALL, mUseBpfStats) != 0) {
		throw new IOException("Failed to parse network stats");