DO NOT MERGE IpConnectivityMetrics: rate limit ApfProgramEvents (b37d43b8) · Commits · e / os / android_frameworks_base

core/java/android/net/IIpConnectivityMetrics.aidl

+2 −1

Original line number	Diff line number	Diff line
		@@ -23,7 +23,8 @@ import android.net.ConnectivityMetricsEvent;
		interface IIpConnectivityMetrics {

		/**
		* @return number of remaining available slots in buffer.
		* @return the number of remaining available slots in buffer,
		* or -1 if the event was dropped due to rate limiting.
		*/
		int logEvent(in ConnectivityMetricsEvent event);
		}

core/tests/coretests/src/android/util/TokenBucketTest.java

+0 −1

Original line number	Diff line number	Diff line
		@@ -177,4 +177,3 @@ public class TokenBucketTest extends TestCase {

		interface Fn { void call(); }
		}

services/core/java/com/android/server/connectivity/IpConnectivityMetrics.java

+24 −0

Original line number	Diff line number	Diff line
		@@ -19,15 +19,19 @@ package com.android.server.connectivity;
		import android.content.Context;
		import android.net.ConnectivityMetricsEvent;
		import android.net.IIpConnectivityMetrics;
		import android.net.metrics.ApfProgramEvent;
		import android.net.metrics.IpConnectivityLog;
		import android.os.IBinder;
		import android.os.Parcelable;
		import android.provider.Settings;
		import android.text.TextUtils;
		import android.text.format.DateUtils;
		import android.util.ArrayMap;
		import android.util.Base64;
		import android.util.Log;
		import com.android.internal.annotations.GuardedBy;
		import com.android.internal.annotations.VisibleForTesting;
		import com.android.internal.util.TokenBucket;
		import com.android.server.SystemService;
		import java.io.FileDescriptor;
		import java.io.IOException;
		@@ -56,6 +60,8 @@ final public class IpConnectivityMetrics extends SystemService {
		// Maximum size of the event buffer.
		private static final int MAXIMUM_BUFFER_SIZE = DEFAULT_BUFFER_SIZE * 10;

		private static final int ERROR_RATE_LIMITED = -1;

		// Lock ensuring that concurrent manipulations of the event buffer are correct.
		// There are three concurrent operations to synchronize:
		// - appending events to the buffer.
		@@ -73,6 +79,8 @@ final public class IpConnectivityMetrics extends SystemService {
		private int mDropped;
		@GuardedBy("mLock")
		private int mCapacity;
		@GuardedBy("mLock")
		private final ArrayMap<Class<?>, TokenBucket> mBuckets = makeRateLimitingBuckets();

		private final ToIntFunction<Context> mCapacityGetter;

		@@ -122,6 +130,10 @@ final public class IpConnectivityMetrics extends SystemService {
		if (event == null) {
		return left;
		}
		if (isRateLimited(event)) {
		// Do not count as a dropped event. TODO: consider adding separate counter
		return ERROR_RATE_LIMITED;
		}
		if (left == 0) {
		mDropped++;
		return 0;
		@@ -131,6 +143,11 @@ final public class IpConnectivityMetrics extends SystemService {
		}
		}

		private boolean isRateLimited(ConnectivityMetricsEvent event) {
		TokenBucket tb = mBuckets.get(event.data.getClass());
		return (tb != null) && !tb.get();
		}

		private String flushEncodedOutput() {
		final ArrayList<ConnectivityMetricsEvent> events;
		final int dropped;
		@@ -253,4 +270,11 @@ final public class IpConnectivityMetrics extends SystemService {
		}
		return Math.min(size, MAXIMUM_BUFFER_SIZE);
		};

		private static ArrayMap<Class<?>, TokenBucket> makeRateLimitingBuckets() {
		ArrayMap<Class<?>, TokenBucket> map = new ArrayMap<>();
		// one token every minute, 50 tokens max: burst of ~50 events every hour.
		map.put(ApfProgramEvent.class, new TokenBucket((int)DateUtils.MINUTE_IN_MILLIS, 50));
		return map;
		}
		}

services/tests/servicestests/src/com/android/server/connectivity/IpConnectivityMetricsTest.java

+22 −0

Original line number	Diff line number	Diff line
		@@ -19,6 +19,7 @@ package com.android.server.connectivity;
		import android.content.Context;
		import android.net.ConnectivityMetricsEvent;
		import android.net.IIpConnectivityMetrics;
		import android.net.metrics.ApfProgramEvent;
		import android.net.metrics.ApfStats;
		import android.net.metrics.DefaultNetworkEvent;
		import android.net.metrics.DhcpClientEvent;
		@@ -112,6 +113,27 @@ public class IpConnectivityMetricsTest extends TestCase {
		assertEquals("", output3);
		}

		public void testRateLimiting() {
		final IpConnectivityLog logger = new IpConnectivityLog(mService.impl);
		final ApfProgramEvent ev = new ApfProgramEvent(0, 0, 0, 0, 0);
		final long fakeTimestamp = 1;

		int attempt = 100; // More than burst quota, but less than buffer size.
		for (int i = 0; i < attempt; i++) {
		logger.log(ev);
		}

		String output1 = getdump("flush");
		assertFalse("".equals(output1));

		for (int i = 0; i < attempt; i++) {
		assertFalse("expected event to be dropped", logger.log(fakeTimestamp, ev));
		}

		String output2 = getdump("flush");
		assertEquals("", output2);
		}

		public void testEndToEndLogging() {
		IpConnectivityLog logger = new IpConnectivityLog(mService.impl);