diff --git a/service-t/src/com/android/server/connectivity/mdns/MdnsFeatureFlags.java b/service-t/src/com/android/server/connectivity/mdns/MdnsFeatureFlags.java index 4e27fef60e..c4a91103e2 100644 --- a/service-t/src/com/android/server/connectivity/mdns/MdnsFeatureFlags.java +++ b/service-t/src/com/android/server/connectivity/mdns/MdnsFeatureFlags.java @@ -89,6 +89,11 @@ public class MdnsFeatureFlags { "nsd_cached_services_retention_time"; public static final int DEFAULT_CACHED_SERVICES_RETENTION_TIME_MILLISECONDS = 10000; + /** + * A feature flag to control whether the accurate delay callback should be enabled. + */ + public static final String NSD_ACCURATE_DELAY_CALLBACK = "nsd_accurate_delay_callback"; + // Flag for offload feature public final boolean mIsMdnsOffloadFeatureEnabled; @@ -122,6 +127,9 @@ public class MdnsFeatureFlags { // Retention Time for cached services public final long mCachedServicesRetentionTime; + // Flag for accurate delay callback + public final boolean mIsAccurateDelayCallbackEnabled; + @Nullable private final FlagOverrideProvider mOverrideProvider; @@ -217,6 +225,14 @@ public class MdnsFeatureFlags { NSD_CACHED_SERVICES_RETENTION_TIME, (int) mCachedServicesRetentionTime); } + /** + * Indicates whether {@link #NSD_ACCURATE_DELAY_CALLBACK} is enabled, including for testing. + */ + public boolean isAccurateDelayCallbackEnabled() { + return mIsAccurateDelayCallbackEnabled + || isForceEnabledForTest(NSD_ACCURATE_DELAY_CALLBACK); + } + /** * The constructor for {@link MdnsFeatureFlags}. */ @@ -231,6 +247,7 @@ public class MdnsFeatureFlags { boolean avoidAdvertisingEmptyTxtRecords, boolean isCachedServicesRemovalEnabled, long cachedServicesRetentionTime, + boolean isAccurateDelayCallbackEnabled, @Nullable FlagOverrideProvider overrideProvider) { mIsMdnsOffloadFeatureEnabled = isOffloadFeatureEnabled; mIncludeInetAddressRecordsInProbing = includeInetAddressRecordsInProbing; @@ -243,6 +260,7 @@ public class MdnsFeatureFlags { mAvoidAdvertisingEmptyTxtRecords = avoidAdvertisingEmptyTxtRecords; mIsCachedServicesRemovalEnabled = isCachedServicesRemovalEnabled; mCachedServicesRetentionTime = cachedServicesRetentionTime; + mIsAccurateDelayCallbackEnabled = isAccurateDelayCallbackEnabled; mOverrideProvider = overrideProvider; } @@ -266,6 +284,7 @@ public class MdnsFeatureFlags { private boolean mAvoidAdvertisingEmptyTxtRecords; private boolean mIsCachedServicesRemovalEnabled; private long mCachedServicesRetentionTime; + private boolean mIsAccurateDelayCallbackEnabled; private FlagOverrideProvider mOverrideProvider; /** @@ -283,6 +302,7 @@ public class MdnsFeatureFlags { mAvoidAdvertisingEmptyTxtRecords = true; // Default enabled. mIsCachedServicesRemovalEnabled = false; mCachedServicesRetentionTime = DEFAULT_CACHED_SERVICES_RETENTION_TIME_MILLISECONDS; + mIsAccurateDelayCallbackEnabled = false; mOverrideProvider = null; } @@ -408,6 +428,16 @@ public class MdnsFeatureFlags { return this; } + /** + * Set whether the accurate delay callback is enabled. + * + * @see #NSD_ACCURATE_DELAY_CALLBACK + */ + public Builder setIsAccurateDelayCallbackEnabled(boolean isAccurateDelayCallbackEnabled) { + mIsAccurateDelayCallbackEnabled = isAccurateDelayCallbackEnabled; + return this; + } + /** * Builds a {@link MdnsFeatureFlags} with the arguments supplied to this builder. */ @@ -423,6 +453,7 @@ public class MdnsFeatureFlags { mAvoidAdvertisingEmptyTxtRecords, mIsCachedServicesRemovalEnabled, mCachedServicesRetentionTime, + mIsAccurateDelayCallbackEnabled, mOverrideProvider); } } diff --git a/service-t/src/com/android/server/connectivity/mdns/MdnsServiceTypeClient.java b/service-t/src/com/android/server/connectivity/mdns/MdnsServiceTypeClient.java index a43486eed9..7a93fecec1 100644 --- a/service-t/src/com/android/server/connectivity/mdns/MdnsServiceTypeClient.java +++ b/service-t/src/com/android/server/connectivity/mdns/MdnsServiceTypeClient.java @@ -20,6 +20,7 @@ import static com.android.net.module.util.HandlerUtils.ensureRunningOnHandlerThr import static com.android.server.connectivity.mdns.MdnsSearchOptions.AGGRESSIVE_QUERY_MODE; import static com.android.server.connectivity.mdns.MdnsServiceCache.ServiceExpiredCallback; import static com.android.server.connectivity.mdns.MdnsServiceCache.findMatchedResponse; +import static com.android.server.connectivity.mdns.MdnsQueryScheduler.ScheduledQueryTaskArgs; import static com.android.server.connectivity.mdns.util.MdnsUtils.Clock; import static com.android.server.connectivity.mdns.util.MdnsUtils.buildMdnsServiceInfoFromResponse; @@ -37,6 +38,7 @@ import androidx.annotation.VisibleForTesting; import com.android.net.module.util.CollectionUtils; import com.android.net.module.util.DnsUtils; import com.android.net.module.util.SharedLog; +import com.android.net.module.util.TimerFileDescriptor; import com.android.server.connectivity.mdns.util.MdnsUtils; import java.io.IOException; @@ -94,6 +96,9 @@ public class MdnsServiceTypeClient { private final boolean removeServiceAfterTtlExpires = MdnsConfigs.removeServiceAfterTtlExpires(); private final Clock clock; + // Use TimerFileDescriptor for query scheduling, which allows for more accurate sending of + // queries. + @NonNull private final TimerFileDescriptor timerFd; @Nullable private MdnsSearchOptions searchOptions; @@ -139,8 +144,7 @@ public class MdnsServiceTypeClient { public void handleMessage(Message msg) { switch (msg.what) { case EVENT_START_QUERYTASK: { - final MdnsQueryScheduler.ScheduledQueryTaskArgs taskArgs = - (MdnsQueryScheduler.ScheduledQueryTaskArgs) msg.obj; + final ScheduledQueryTaskArgs taskArgs = (ScheduledQueryTaskArgs) msg.obj; // QueryTask should be run immediately after being created (not be scheduled in // advance). Because the result of "makeResponsesForResolve" depends on answers // that were received before it is called, so to take into account all answers @@ -174,7 +178,7 @@ public class MdnsServiceTypeClient { final long now = clock.elapsedRealtime(); lastSentTime = now; final long minRemainingTtl = getMinRemainingTtl(now); - MdnsQueryScheduler.ScheduledQueryTaskArgs args = + final ScheduledQueryTaskArgs args = mdnsQueryScheduler.scheduleNextRun( sentResult.taskArgs.config, minRemainingTtl, @@ -189,10 +193,14 @@ public class MdnsServiceTypeClient { sharedLog.log(String.format("Query sent with transactionId: %d. " + "Next run: sessionId: %d, in %d ms", sentResult.transactionId, args.sessionId, timeToNextTaskMs)); - dependencies.sendMessageDelayed( - handler, - handler.obtainMessage(EVENT_START_QUERYTASK, args), - timeToNextTaskMs); + if (featureFlags.isAccurateDelayCallbackEnabled()) { + setDelayedTask(args, timeToNextTaskMs); + } else { + dependencies.sendMessageDelayed( + handler, + handler.obtainMessage(EVENT_START_QUERYTASK, args), + timeToNextTaskMs); + } break; } default: @@ -254,6 +262,14 @@ public class MdnsServiceTypeClient { return List.of(new DatagramPacket(queryBuffer, 0, queryBuffer.length, address)); } } + + /** + * @see TimerFileDescriptor + */ + @Nullable + public TimerFileDescriptor createTimerFd(@NonNull Handler handler) { + return new TimerFileDescriptor(handler); + } } /** @@ -301,6 +317,7 @@ public class MdnsServiceTypeClient { this.mdnsQueryScheduler = new MdnsQueryScheduler(); this.cacheKey = new MdnsServiceCache.CacheKey(serviceType, socketKey); this.featureFlags = featureFlags; + this.timerFd = dependencies.createTimerFd(handler); } /** @@ -317,6 +334,13 @@ public class MdnsServiceTypeClient { ? serviceCache.getCachedServices(cacheKey) : Collections.emptyList(); } + private void setDelayedTask(ScheduledQueryTaskArgs args, long timeToNextTaskMs) { + timerFd.cancelTask(); + timerFd.setDelayedTask(new TimerFileDescriptor.MessageTask( + handler.obtainMessage(EVENT_START_QUERYTASK, args)), + timeToNextTaskMs); + } + /** * Registers {@code listener} for receiving discovery event of mDNS service instances, and * starts @@ -363,7 +387,7 @@ public class MdnsServiceTypeClient { } final long minRemainingTtl = getMinRemainingTtl(now); if (hadReply) { - MdnsQueryScheduler.ScheduledQueryTaskArgs args = + final ScheduledQueryTaskArgs args = mdnsQueryScheduler.scheduleNextRun( taskConfig, minRemainingTtl, @@ -377,10 +401,14 @@ public class MdnsServiceTypeClient { final long timeToNextTaskMs = calculateTimeToNextTask(args, now); sharedLog.log(String.format("Schedule a query. Next run: sessionId: %d, in %d ms", args.sessionId, timeToNextTaskMs)); - dependencies.sendMessageDelayed( - handler, - handler.obtainMessage(EVENT_START_QUERYTASK, args), - timeToNextTaskMs); + if (featureFlags.isAccurateDelayCallbackEnabled()) { + setDelayedTask(args, timeToNextTaskMs); + } else { + dependencies.sendMessageDelayed( + handler, + handler.obtainMessage(EVENT_START_QUERYTASK, args), + timeToNextTaskMs); + } } else { final List servicesToResolve = makeResponsesForResolve(socketKey); final QueryTask queryTask = new QueryTask( @@ -420,7 +448,11 @@ public class MdnsServiceTypeClient { } private void removeScheduledTask() { - dependencies.removeMessages(handler, EVENT_START_QUERYTASK); + if (featureFlags.isAccurateDelayCallbackEnabled()) { + timerFd.cancelTask(); + } else { + dependencies.removeMessages(handler, EVENT_START_QUERYTASK); + } sharedLog.log("Remove EVENT_START_QUERYTASK" + ", current session: " + currentSessionId); ++currentSessionId; @@ -506,10 +538,13 @@ public class MdnsServiceTypeClient { } } } - if (dependencies.hasMessages(handler, EVENT_START_QUERYTASK)) { + final boolean hasScheduledTask = featureFlags.isAccurateDelayCallbackEnabled() + ? timerFd.hasDelayedTask() + : dependencies.hasMessages(handler, EVENT_START_QUERYTASK); + if (hasScheduledTask) { final long now = clock.elapsedRealtime(); final long minRemainingTtl = getMinRemainingTtl(now); - MdnsQueryScheduler.ScheduledQueryTaskArgs args = + final ScheduledQueryTaskArgs args = mdnsQueryScheduler.maybeRescheduleCurrentRun(now, minRemainingTtl, lastSentTime, currentSessionId + 1, searchOptions.numOfQueriesBeforeBackoff()); @@ -518,10 +553,14 @@ public class MdnsServiceTypeClient { final long timeToNextTaskMs = calculateTimeToNextTask(args, now); sharedLog.log(String.format("Reschedule a query. Next run: sessionId: %d, in %d ms", args.sessionId, timeToNextTaskMs)); - dependencies.sendMessageDelayed( - handler, - handler.obtainMessage(EVENT_START_QUERYTASK, args), - timeToNextTaskMs); + if (featureFlags.isAccurateDelayCallbackEnabled()) { + setDelayedTask(args, timeToNextTaskMs); + } else { + dependencies.sendMessageDelayed( + handler, + handler.obtainMessage(EVENT_START_QUERYTASK, args), + timeToNextTaskMs); + } } } } @@ -686,10 +725,10 @@ public class MdnsServiceTypeClient { private static class QuerySentArguments { private final int transactionId; private final List subTypes = new ArrayList<>(); - private final MdnsQueryScheduler.ScheduledQueryTaskArgs taskArgs; + private final ScheduledQueryTaskArgs taskArgs; QuerySentArguments(int transactionId, @NonNull List subTypes, - @NonNull MdnsQueryScheduler.ScheduledQueryTaskArgs taskArgs) { + @NonNull ScheduledQueryTaskArgs taskArgs) { this.transactionId = transactionId; this.subTypes.addAll(subTypes); this.taskArgs = taskArgs; @@ -698,14 +737,14 @@ public class MdnsServiceTypeClient { // A FutureTask that enqueues a single query, and schedule a new FutureTask for the next task. private class QueryTask implements Runnable { - private final MdnsQueryScheduler.ScheduledQueryTaskArgs taskArgs; + private final ScheduledQueryTaskArgs taskArgs; private final List servicesToResolve = new ArrayList<>(); private final List subtypes = new ArrayList<>(); private final boolean sendDiscoveryQueries; private final List existingServices = new ArrayList<>(); private final boolean onlyUseIpv6OnIpv6OnlyNetworks; private final SocketKey socketKey; - QueryTask(@NonNull MdnsQueryScheduler.ScheduledQueryTaskArgs taskArgs, + QueryTask(@NonNull ScheduledQueryTaskArgs taskArgs, @NonNull Collection servicesToResolve, @NonNull Collection subtypes, boolean sendDiscoveryQueries, @NonNull Collection existingServices, @@ -771,7 +810,7 @@ public class MdnsServiceTypeClient { return minRemainingTtl == Long.MAX_VALUE ? 0 : minRemainingTtl; } - private static long calculateTimeToNextTask(MdnsQueryScheduler.ScheduledQueryTaskArgs args, + private static long calculateTimeToNextTask(ScheduledQueryTaskArgs args, long now) { return Math.max(args.timeToRun - now, 0); } diff --git a/staticlibs/Android.bp b/staticlibs/Android.bp index b5ee7892b6..046b0355f9 100644 --- a/staticlibs/Android.bp +++ b/staticlibs/Android.bp @@ -438,7 +438,10 @@ java_library { srcs: [ "device/com/android/net/module/util/FdEventsReader.java", "device/com/android/net/module/util/HandlerUtils.java", + "device/com/android/net/module/util/JniUtil.java", "device/com/android/net/module/util/SharedLog.java", + "device/com/android/net/module/util/TimerFdUtils.java", + "device/com/android/net/module/util/TimerFileDescriptor.java", "framework/com/android/net/module/util/ByteUtils.java", "framework/com/android/net/module/util/CollectionUtils.java", "framework/com/android/net/module/util/DnsUtils.java", diff --git a/staticlibs/device/com/android/net/module/util/TimerFileDescriptor.java b/staticlibs/device/com/android/net/module/util/TimerFileDescriptor.java index dbbccc54a5..a8c0f171fa 100644 --- a/staticlibs/device/com/android/net/module/util/TimerFileDescriptor.java +++ b/staticlibs/device/com/android/net/module/util/TimerFileDescriptor.java @@ -103,6 +103,13 @@ public class TimerFileDescriptor { public void post(Handler handler) { handler.sendMessage(mMessage); } + + /** + * Get scheduled message + */ + public Message getMessage() { + return mMessage; + } } /** diff --git a/tests/unit/java/com/android/server/connectivity/mdns/MdnsServiceTypeClientTests.java b/tests/unit/java/com/android/server/connectivity/mdns/MdnsServiceTypeClientTests.java index da0bc88236..ed95e4bc2d 100644 --- a/tests/unit/java/com/android/server/connectivity/mdns/MdnsServiceTypeClientTests.java +++ b/tests/unit/java/com/android/server/connectivity/mdns/MdnsServiceTypeClientTests.java @@ -60,6 +60,7 @@ import android.text.TextUtils; import com.android.net.module.util.CollectionUtils; import com.android.net.module.util.SharedLog; +import com.android.net.module.util.TimerFileDescriptor; import com.android.server.connectivity.mdns.MdnsServiceInfo.TextEntry; import com.android.server.connectivity.mdns.util.MdnsUtils; import com.android.testutils.DevSdkIgnoreRule; @@ -127,6 +128,8 @@ public class MdnsServiceTypeClientTests { private SharedLog mockSharedLog; @Mock private MdnsServiceTypeClient.Dependencies mockDeps; + @Mock + private TimerFileDescriptor mockTimerFd; @Captor private ArgumentCaptor serviceInfoCaptor; @@ -145,6 +148,7 @@ public class MdnsServiceTypeClientTests { private Message delayMessage = null; private Handler realHandler = null; private MdnsFeatureFlags featureFlags = MdnsFeatureFlags.newBuilder().build(); + private TimerFileDescriptor.MessageTask task = null; @Before @SuppressWarnings("DoNotMock") @@ -244,10 +248,21 @@ public class MdnsServiceTypeClientTests { return true; }).when(mockDeps).sendMessage(any(Handler.class), any(Message.class)); - client = makeMdnsServiceTypeClient(); + doAnswer(inv -> { + realHandler = (Handler) inv.getArguments()[0]; + return mockTimerFd; + }).when(mockDeps).createTimerFd(any(Handler.class)); + + doAnswer(inv -> { + task = (TimerFileDescriptor.MessageTask) inv.getArguments()[0]; + latestDelayMs = (long) inv.getArguments()[1]; + return null; + }).when(mockTimerFd).setDelayedTask(any(), anyLong()); + + client = makeMdnsServiceTypeClient(featureFlags); } - private MdnsServiceTypeClient makeMdnsServiceTypeClient() { + private MdnsServiceTypeClient makeMdnsServiceTypeClient(MdnsFeatureFlags featureFlags) { return new MdnsServiceTypeClient(SERVICE_TYPE, mockSocketClient, currentThreadExecutor, mockDecoderClock, socketKey, mockSharedLog, thread.getLooper(), mockDeps, serviceCache, featureFlags); @@ -1926,9 +1941,7 @@ public class MdnsServiceTypeClientTests { @Test public void testSendQueryWithKnownAnswers() throws Exception { - client = new MdnsServiceTypeClient(SERVICE_TYPE, mockSocketClient, currentThreadExecutor, - mockDecoderClock, socketKey, mockSharedLog, thread.getLooper(), mockDeps, - serviceCache, + client = makeMdnsServiceTypeClient( MdnsFeatureFlags.newBuilder().setIsQueryWithKnownAnswerEnabled(true).build()); doCallRealMethod().when(mockDeps).getDatagramPacketsFromMdnsPacket( @@ -1990,9 +2003,7 @@ public class MdnsServiceTypeClientTests { @Test public void testSendQueryWithSubTypeWithKnownAnswers() throws Exception { - client = new MdnsServiceTypeClient(SERVICE_TYPE, mockSocketClient, currentThreadExecutor, - mockDecoderClock, socketKey, mockSharedLog, thread.getLooper(), mockDeps, - serviceCache, + client = makeMdnsServiceTypeClient( MdnsFeatureFlags.newBuilder().setIsQueryWithKnownAnswerEnabled(true).build()); doCallRealMethod().when(mockDeps).getDatagramPacketsFromMdnsPacket( @@ -2114,6 +2125,66 @@ public class MdnsServiceTypeClientTests { assertEquals(9680L, latestDelayMs); } + @Test + public void sendQueries_AccurateDelayCallback() { + client = makeMdnsServiceTypeClient( + MdnsFeatureFlags.newBuilder().setIsAccurateDelayCallbackEnabled(true).build()); + + final int numOfQueriesBeforeBackoff = 2; + final MdnsSearchOptions searchOptions = MdnsSearchOptions.newBuilder() + .addSubtype(SUBTYPE) + .setQueryMode(AGGRESSIVE_QUERY_MODE) + .setNumOfQueriesBeforeBackoff(numOfQueriesBeforeBackoff) + .build(); + startSendAndReceive(mockListenerOne, searchOptions); + verify(mockTimerFd, times(1)).cancelTask(); + + // Verify that the first query has been sent. + verifyAndSendQuery(0 /* index */, 0 /* timeInMs */, true /* expectsUnicastResponse */, + true /* multipleSocketDiscovery */, 1 /* scheduledCount */, + 1 /* sendMessageCount */, true /* useAccurateDelayCallback */); + // Verify that the task cancellation occurred before scheduling another query. + verify(mockTimerFd, times(2)).cancelTask(); + + // Verify that the second query has been sent + verifyAndSendQuery(1 /* index */, 0 /* timeInMs */, false /* expectsUnicastResponse */, + true /* multipleSocketDiscovery */, 2 /* scheduledCount */, + 2 /* sendMessageCount */, true /* useAccurateDelayCallback */); + // Verify that the task cancellation occurred before scheduling another query. + verify(mockTimerFd, times(3)).cancelTask(); + + // Verify that the third query has been sent + verifyAndSendQuery(2 /* index */, TIME_BETWEEN_RETRANSMISSION_QUERIES_IN_BURST_MS, + false /* expectsUnicastResponse */, true /* multipleSocketDiscovery */, + 3 /* scheduledCount */, 3 /* sendMessageCount */, + true /* useAccurateDelayCallback */); + // Verify that the task cancellation occurred before scheduling another query. + verify(mockTimerFd, times(4)).cancelTask(); + + // In backoff mode, the current scheduled task will be canceled and reschedule if the + // 0.8 * smallestRemainingTtl is larger than time to next run. + long currentTime = TEST_TTL / 2 + TEST_ELAPSED_REALTIME; + doReturn(currentTime).when(mockDecoderClock).elapsedRealtime(); + doReturn(true).when(mockTimerFd).hasDelayedTask(); + processResponse(createResponse( + "service-instance-1", "192.0.2.123", 5353, + SERVICE_TYPE_LABELS, + Collections.emptyMap(), TEST_TTL), socketKey); + // Verify that the task cancellation occurred twice. + verify(mockTimerFd, times(6)).cancelTask(); + assertNotNull(task); + verifyAndSendQuery(3 /* index */, (long) (TEST_TTL / 2 * 0.8) /* timeInMs */, + true /* expectsUnicastResponse */, true /* multipleSocketDiscovery */, + 5 /* scheduledCount */, 4 /* sendMessageCount */, + true /* useAccurateDelayCallback */); + // Verify that the task cancellation occurred before scheduling another query. + verify(mockTimerFd, times(7)).cancelTask(); + + // Stop sending packets. + stopSendAndReceive(mockListenerOne); + verify(mockTimerFd, times(8)).cancelTask(); + } + private static MdnsServiceInfo matchServiceName(String name) { return argThat(info -> info.getServiceInstanceName().equals(name)); } @@ -2127,9 +2198,22 @@ public class MdnsServiceTypeClientTests { private void verifyAndSendQuery(int index, long timeInMs, boolean expectsUnicastResponse, boolean multipleSocketDiscovery, int scheduledCount) { - // Dispatch the message - if (delayMessage != null && realHandler != null) { - dispatchMessage(); + verifyAndSendQuery(index, timeInMs, expectsUnicastResponse, + multipleSocketDiscovery, scheduledCount, index + 1 /* sendMessageCount */, + false /* useAccurateDelayCallback */); + } + + private void verifyAndSendQuery(int index, long timeInMs, boolean expectsUnicastResponse, + boolean multipleSocketDiscovery, int scheduledCount, int sendMessageCount, + boolean useAccurateDelayCallback) { + if (useAccurateDelayCallback && task != null && realHandler != null) { + runOnHandler(() -> realHandler.dispatchMessage(task.getMessage())); + task = null; + } else { + // Dispatch the message + if (delayMessage != null && realHandler != null) { + dispatchMessage(); + } } assertEquals(timeInMs, latestDelayMs); currentThreadExecutor.getAndClearLastScheduledRunnable().run(); @@ -2152,11 +2236,15 @@ public class MdnsServiceTypeClientTests { eq(socketKey), eq(false)); } } - verify(mockDeps, times(index + 1)) + verify(mockDeps, times(sendMessageCount)) .sendMessage(any(Handler.class), any(Message.class)); // Verify the task has been scheduled. - verify(mockDeps, times(scheduledCount)) - .sendMessageDelayed(any(Handler.class), any(Message.class), anyLong()); + if (useAccurateDelayCallback) { + verify(mockTimerFd, times(scheduledCount)).setDelayedTask(any(), anyLong()); + } else { + verify(mockDeps, times(scheduledCount)) + .sendMessageDelayed(any(Handler.class), any(Message.class), anyLong()); + } } private static String[] getTestServiceName(String instanceName) {