Merge "Fix BoundServiceSession bookkeeping" into main (1d4abc78) · Commits · e / os / android_frameworks_base

services/core/java/com/android/server/am/BoundServiceSession.java

+56 −20

Original line number	Diff line number	Diff line
		@@ -22,6 +22,7 @@ import android.os.Trace;
		import android.ravenwood.annotation.RavenwoodKeepWholeClass;
		import android.util.ArrayMap;
		import android.util.IndentingPrintWriter;
		import android.util.IntArray;
		import android.util.Slog;

		import com.android.internal.annotations.GuardedBy;
		@@ -30,11 +31,15 @@ import com.android.internal.util.IntPair;

		import java.lang.ref.WeakReference;
		import java.util.function.BiConsumer;
		import java.util.function.Supplier;

		/**
		* An implementation of {@link IBinderSession} on top of a {@link ConnectionRecord} that
		* is used to facilitate important binder calls to a bound remote service hosted by a process that
		* is eligible to get frozen by {@link ProcessStateController}.
		*
		* <p>This class simply keeps the count of ongoing transactions over a bound service's binder and
		* notifies {@link ProcessStateController} when the count changes to or from 0.
		*/
		@RavenwoodKeepWholeClass
		public class BoundServiceSession implements IBinderSession {
		@@ -42,6 +47,13 @@ public class BoundServiceSession implements IBinderSession {
		private static final int MAGIC_ID = 0xFBD_5E55;
		private static final String TRACE_TRACK = "bound_service_calls";

		/** Tag to use for all tags after we have {@link #MAX_UNIQUE_TAGS} tags within the session. */
		@VisibleForTesting
		static final String OVERFLOW_TAG = "_overflow_tags";
		/** Any new tags after this limit will be clubbed together under {@link #OVERFLOW_TAG}. */
		@VisibleForTesting
		static final int MAX_UNIQUE_TAGS = 127;

		// We don't hold a strong reference in case this object is held on for a long time after the
		// binding has gone away. This helps us easily avoid leaks and excess OomAdjuster updates
		// while remaining agnostic to binding state changes. This is also a convenient long-term choice
		@@ -50,9 +62,17 @@ public class BoundServiceSession implements IBinderSession {
		private final BiConsumer<ConnectionRecord, Boolean> mProcessStateUpdater;
		private final String mDebugName;

		/**
		* For each unique tag, we generate a stable key which is simply the index of the counter
		* maintained in {@link #mCountByKey} array. We encapsulate this information in the generated
		* token which is returned to the client to pass in {@link #binderTransactionCompleted(long)}.
		*/
		@VisibleForTesting
		@GuardedBy("this")
		final ArrayMap<String, Integer> mKeyByTag = new ArrayMap<>();
		@VisibleForTesting
		@GuardedBy("this")
		ArrayMap<String, Integer> mCountsByTag = null;
		final IntArray mCountByKey = new IntArray();

		@VisibleForTesting
		@GuardedBy("this")
		@@ -73,7 +93,7 @@ public class BoundServiceSession implements IBinderSession {
		return IntPair.first(token) == MAGIC_ID;
		}

		private static int getKeyIndex(long token) {
		private static int getKey(long token) {
		return IntPair.second(token);
		}

		@@ -88,10 +108,10 @@ public class BoundServiceSession implements IBinderSession {
		mProcessStateUpdater.accept(strongCr, mTotal > 0);
		}

		private void logTraceInstant(String message) {
		private void logTraceInstant(Supplier<String> messageSupplier) {
		if (Trace.isTagEnabled(Trace.TRACE_TAG_ACTIVITY_MANAGER)) {
		Trace.instantForTrack(Trace.TRACE_TAG_ACTIVITY_MANAGER, TRACE_TRACK, mDebugName
		+ ": " + message);
		+ ": " + messageSupplier.get());
		}
		}

		@@ -101,9 +121,11 @@ public class BoundServiceSession implements IBinderSession {
		// cannot tell for which tag. We'll just reset all counts to 0 and propagate the same to
		// the underlying ConnectionRecord. This also ensures that there are no shenanigans that
		// the remote app can perform with the given token to remain unfrozen.
		logTraceInstant(errorMessage);
		Slog.wtfStack(TAG, errorMessage);
		mCountsByTag.clear();
		logTraceInstant(() -> errorMessage);
		Slog.wtfStack(TAG,
		errorMessage + ". Current keys: " + mKeyByTag + "; Counts: " + mCountByKey);
		mKeyByTag.clear();
		mCountByKey.clear();
		if (mTotal != 0) {
		mTotal = 0;
		maybePostProcessStateUpdate();
		@@ -112,17 +134,31 @@ public class BoundServiceSession implements IBinderSession {

		@Override
		public long binderTransactionStarting(String debugTag) {
		logTraceInstant("+" + debugTag);
		synchronized (this) {
		if (mCountsByTag == null) {
		mCountsByTag = new ArrayMap<>(4);
		}
		mCountsByTag.merge(debugTag, 1, (old, _unused) -> old + 1);
		final int key;
		if (mKeyByTag.size() >= MAX_UNIQUE_TAGS) {
		// The values in mKeyByTag are always in the range [0, mKeyByTag.size() - 1].
		key = mKeyByTag.getOrDefault(debugTag, MAX_UNIQUE_TAGS);
		if (key == MAX_UNIQUE_TAGS && mKeyByTag.size() == MAX_UNIQUE_TAGS) {
		Slog.wtfStack(TAG, "Too many tags supplied on " + mDebugName
		+ ". Current tag: " + debugTag + ". Existing map: " + mKeyByTag);
		mKeyByTag.put(OVERFLOW_TAG, key);
		mCountByKey.add(0);
		}
		} else {
		key = mKeyByTag.computeIfAbsent(debugTag, unused -> {
		mCountByKey.add(0);
		return mCountByKey.size() - 1;
		});
		}
		final long token = getToken(key);
		logTraceInstant(() -> "open(" + debugTag + ", " + token + ")");
		mCountByKey.set(key, mCountByKey.get(key) + 1);
		mTotal++;
		if (mTotal == 1) {
		maybePostProcessStateUpdate();
		}
		return getToken(mCountsByTag.indexOfKey(debugTag));
		return token;
		}
		}

		@@ -135,15 +171,15 @@ public class BoundServiceSession implements IBinderSession {
		+ mDebugName);
		return;
		}
		final int keyIndex = getKeyIndex(token);
		if (mCountsByTag.size() <= keyIndex \|\| mCountsByTag.valueAt(keyIndex) <= 0) {
		handleInvalidToken("Bad keyIndex " + keyIndex
		final int key = getKey(token);
		if (mCountByKey.size() <= key \|\| mCountByKey.get(key) <= 0) {
		handleInvalidToken("Bad key " + key
		+ " received in binderTransactionCompleted! Closing all transactions on "
		+ mDebugName);
		return;
		}
		logTraceInstant("-" + mCountsByTag.keyAt(keyIndex));
		mCountsByTag.setValueAt(keyIndex, mCountsByTag.valueAt(keyIndex) - 1);
		logTraceInstant(() -> "close(" + key + ")");
		mCountByKey.set(key, mCountByKey.get(key) - 1);
		mTotal--;
		if (mTotal == 0) {
		maybePostProcessStateUpdate();
		@@ -161,10 +197,10 @@ public class BoundServiceSession implements IBinderSession {
		ipw.print("Ongoing bound service calls: ");
		ipw.println(mTotal);

		if (mCountsByTag != null) {
		if (mTotal > 0) {
		ipw.increaseIndent();
		for (int i = 0; i < mCountsByTag.size(); i++) {
		ipw.print(mCountsByTag.keyAt(i), mCountsByTag.valueAt(i));
		for (int i = 0; i < mKeyByTag.size(); i++) {
		ipw.print(mKeyByTag.keyAt(i), mCountByKey.get(mKeyByTag.valueAt(i)));
		}
		ipw.println();
		ipw.decreaseIndent();

services/tests/servicestests/src/com/android/server/am/BoundServiceSessionTests.java

+157 −44

Original line number	Diff line number	Diff line
		@@ -16,8 +16,13 @@

		package com.android.server.am;

		import static com.android.server.am.BoundServiceSession.MAX_UNIQUE_TAGS;
		import static com.android.server.am.BoundServiceSession.OVERFLOW_TAG;

		import static org.junit.Assert.assertEquals;
		import static org.junit.Assert.assertNull;
		import static org.junit.Assert.assertFalse;
		import static org.junit.Assert.assertTrue;
		import static org.junit.Assert.fail;
		import static org.mockito.ArgumentMatchers.any;
		import static org.mockito.ArgumentMatchers.anyBoolean;
		import static org.mockito.Mockito.clearInvocations;
		@@ -31,6 +36,8 @@ import android.platform.test.annotations.Presubmit;
		import org.junit.Test;

		import java.lang.ref.WeakReference;
		import java.util.ArrayList;
		import java.util.List;
		import java.util.function.BiConsumer;

		/**
		@@ -39,7 +46,7 @@ import java.util.function.BiConsumer;
		* Build/Install/Run:
		* atest FrameworksServicesTests:BoundServiceSessionTests
		* Or
		* atest FrameworksServicesTestsRavenwood_ProcessStateController
		* atest FrameworksServicesTestsRavenwood_ProcessStateController:BoundServiceSessionTests
		*/
		@Presubmit
		public class BoundServiceSessionTests {
		@@ -56,14 +63,14 @@ public class BoundServiceSessionTests {

		private static void assertSessionReset(BoundServiceSession session) {
		assertEquals(0, session.mTotal);
		assertEquals(0, session.mCountsByTag.size());
		assertEquals(0, session.mKeyByTag.size());
		assertEquals(0, session.mCountByKey.size());
		}

		@Test
		public void startingState() {
		final BoundServiceSession session = getNewBoundServiceSessionForTest();
		assertEquals(0, session.mTotal);
		assertNull(session.mCountsByTag);
		assertSessionReset(session);
		}

		@Test
		@@ -78,14 +85,19 @@ public class BoundServiceSessionTests {

		final long token1 = session.binderTransactionStarting(testTags[1]);

		assertEquals(4, (int) session.mCountsByTag.get(testTags[0]));
		assertEquals(1, (int) session.mCountsByTag.get(testTags[1]));
		final int key0 = session.mKeyByTag.get(testTags[0]);
		final int key1 = session.mKeyByTag.get(testTags[1]);
		assertEquals(0, key0);
		assertEquals(1, key1);

		assertEquals(4, session.mCountByKey.get(key0));
		assertEquals(1, session.mCountByKey.get(key1));
		assertEquals(5, session.mTotal);

		session.binderTransactionCompleted(token1);

		assertEquals(4, (int) session.mCountsByTag.get(testTags[0]));
		assertEquals(0, (int) session.mCountsByTag.get(testTags[1]));
		assertEquals(4, session.mCountByKey.get(key0));
		assertEquals(0, session.mCountByKey.get(key1));
		assertEquals(4, session.mTotal);

		session.binderTransactionCompleted(token1);
		@@ -101,8 +113,10 @@ public class BoundServiceSessionTests {
		session.binderTransactionStarting(testTag);
		session.binderTransactionStarting(testTag);

		int key = session.mKeyByTag.get(testTag);
		assertEquals(0, key);
		assertEquals(3, session.mTotal);
		assertEquals(3, (int) session.mCountsByTag.get(testTag));
		assertEquals(3, session.mCountByKey.get(key));

		session.binderTransactionCompleted(validToken + 1);
		assertSessionReset(session);
		@@ -110,8 +124,10 @@ public class BoundServiceSessionTests {
		session.binderTransactionStarting(testTag);
		session.binderTransactionStarting(testTag);

		key = session.mKeyByTag.get(testTag);
		assertEquals(0, key);
		assertEquals(2, session.mTotal);
		assertEquals(2, (int) session.mCountsByTag.get(testTag));
		assertEquals(2, session.mCountByKey.get(key));

		session.binderTransactionCompleted(-1);
		assertSessionReset(session);
		@@ -121,7 +137,7 @@ public class BoundServiceSessionTests {
		public void tokenConsistency() {
		final BoundServiceSession session = getNewBoundServiceSessionForTest();

		final String[] testTags = {"test0", "test1", "test2"};
		final String[] testTags = {"test5", "test1", "test2"};

		final long token0 = session.binderTransactionStarting(testTags[0]);
		final long token1 = session.binderTransactionStarting(testTags[1]);
		@@ -132,6 +148,24 @@ public class BoundServiceSessionTests {
		assertEquals(token2, session.binderTransactionStarting(testTags[2]));
		}

		@Test
		public void tokenDistinctness() {
		final BoundServiceSession session = getNewBoundServiceSessionForTest();

		final String[] tags = {"test3", "test1", "otherTag", "test2"};
		final List<Long> tokens = new ArrayList<>();

		for (String tag: tags) {
		final long token = session.binderTransactionStarting(tag);
		final int index = tokens.indexOf(token);
		if (index >= 0) {
		fail("Duplicate token " + token + " found for tag " + tag
		+ ". Previously assigned to tag " + tags[index]);
		}
		tokens.add(token);
		}
		}

		@Test
		public void callsConsumerOnChangeFromZero() {
		final BoundServiceSession session = getNewBoundServiceSessionForTest();
		@@ -201,57 +235,136 @@ public class BoundServiceSessionTests {
		verify(mMockConsumer, never()).accept(any(ConnectionRecord.class), anyBoolean());
		}

		@Test
		public void keyKeeping() {
		final BoundServiceSession session = getNewBoundServiceSessionForTest();

		final String[] tags = {"test3", "test1", "otherTag", "test2"};
		final List<Integer> keys = new ArrayList<>();

		for (String tag: tags) {
		assertFalse(session.mKeyByTag.containsKey(tag));
		session.binderTransactionStarting(tag);

		final int key = session.mKeyByTag.get(tag);
		final int index = keys.indexOf(key);
		if (index >= 0) {
		fail("Duplicate key " + key + " found for tag " + tag
		+ ". Previously assigned to tag " + tags[index]);
		}
		keys.add(key);
		}

		// Ensure that keys don't change once assigned.
		for (int i = 0; i < tags.length; i++) {
		assertEquals(keys.get(i), session.mKeyByTag.get(tags[i]));
		session.binderTransactionStarting(tags[i]);
		assertEquals(keys.get(i), session.mKeyByTag.get(tags[i]));
		}
		}

		@Test
		public void countKeeping() {
		final BoundServiceSession session = getNewBoundServiceSessionForTest();

		final String[] testTags = {"test0", "test1", "test2"};
		final String[] tags = {"test3", "otherTag", "test0"};
		final List<Long> tokens = new ArrayList<>();
		final List<Integer> keys = new ArrayList<>();

		final long token0 = session.binderTransactionStarting(testTags[0]);
		final long token1 = session.binderTransactionStarting(testTags[1]);
		final long token2 = session.binderTransactionStarting(testTags[2]);
		for (String tag: tags) {
		tokens.add(session.binderTransactionStarting(tag));
		keys.add(session.mKeyByTag.get(tag));
		}

		session.binderTransactionStarting(testTags[1]);
		session.binderTransactionStarting(testTags[2]);
		session.binderTransactionStarting(testTags[2]);
		session.binderTransactionStarting(tags[1]);
		session.binderTransactionStarting(tags[2]);
		session.binderTransactionStarting(tags[2]);

		assertEquals(1, (int) session.mCountsByTag.get(testTags[0]));
		assertEquals(2, (int) session.mCountsByTag.get(testTags[1]));
		assertEquals(3, (int) session.mCountsByTag.get(testTags[2]));
		assertEquals(1, session.mCountByKey.get(keys.get(0)));
		assertEquals(2, session.mCountByKey.get(keys.get(1)));
		assertEquals(3, session.mCountByKey.get(keys.get(2)));
		assertEquals(6, session.mTotal);

		session.binderTransactionCompleted(token0);
		session.binderTransactionCompleted(token1);
		session.binderTransactionCompleted(token2);
		session.binderTransactionCompleted(tokens.get(0));
		session.binderTransactionCompleted(tokens.get(1));
		session.binderTransactionCompleted(tokens.get(2));

		assertEquals(0, (int) session.mCountsByTag.get(testTags[0]));
		assertEquals(1, (int) session.mCountsByTag.get(testTags[1]));
		assertEquals(2, (int) session.mCountsByTag.get(testTags[2]));
		assertEquals(0, session.mCountByKey.get(keys.get(0)));
		assertEquals(1, session.mCountByKey.get(keys.get(1)));
		assertEquals(2, session.mCountByKey.get(keys.get(2)));
		assertEquals(3, session.mTotal);

		session.binderTransactionCompleted(token1);
		session.binderTransactionCompleted(token2);
		session.binderTransactionCompleted(tokens.get(1));
		session.binderTransactionCompleted(tokens.get(2));

		assertEquals(0, (int) session.mCountsByTag.get(testTags[0]));
		assertEquals(0, (int) session.mCountsByTag.get(testTags[1]));
		assertEquals(1, (int) session.mCountsByTag.get(testTags[2]));
		assertEquals(0, session.mCountByKey.get(keys.get(0)));
		assertEquals(0, session.mCountByKey.get(keys.get(1)));
		assertEquals(1, session.mCountByKey.get(keys.get(2)));
		assertEquals(1, session.mTotal);

		session.binderTransactionStarting(testTags[0]);
		session.binderTransactionStarting(testTags[1]);
		session.binderTransactionStarting(tags[0]);
		session.binderTransactionStarting(tags[1]);

		assertEquals(1, (int) session.mCountsByTag.get(testTags[0]));
		assertEquals(1, (int) session.mCountsByTag.get(testTags[1]));
		assertEquals(1, (int) session.mCountsByTag.get(testTags[2]));
		assertEquals(1, session.mCountByKey.get(keys.get(0)));
		assertEquals(1, session.mCountByKey.get(keys.get(1)));
		assertEquals(1, session.mCountByKey.get(keys.get(2)));
		assertEquals(3, session.mTotal);

		session.binderTransactionCompleted(token0);
		session.binderTransactionCompleted(token1);
		session.binderTransactionCompleted(token2);
		session.binderTransactionCompleted(tokens.get(0));
		session.binderTransactionCompleted(tokens.get(1));
		session.binderTransactionCompleted(tokens.get(2));

		assertEquals(0, (int) session.mCountsByTag.get(testTags[0]));
		assertEquals(0, (int) session.mCountsByTag.get(testTags[1]));
		assertEquals(0, (int) session.mCountsByTag.get(testTags[2]));
		assertEquals(0, session.mCountByKey.get(keys.get(0)));
		assertEquals(0, session.mCountByKey.get(keys.get(1)));
		assertEquals(0, session.mCountByKey.get(keys.get(2)));
		assertEquals(0, session.mTotal);
		}

		@Test
		public void overflowTags() {
		final BoundServiceSession session = getNewBoundServiceSessionForTest();

		final List<String> uniqueTags = new ArrayList<>(MAX_UNIQUE_TAGS);
		for (int i = 0; i < MAX_UNIQUE_TAGS; i++) {
		final String tag = "unique_tag" + i;
		uniqueTags.add(tag);
		session.binderTransactionStarting(tag);
		assertEquals(i, (int) session.mKeyByTag.getOrDefault(tag, -1));
		assertEquals(1, session.mCountByKey.get(i));
		}
		assertEquals(MAX_UNIQUE_TAGS, session.mCountByKey.size());
		assertEquals(MAX_UNIQUE_TAGS, session.mKeyByTag.size());
		assertFalse(session.mKeyByTag.containsKey(OVERFLOW_TAG));

		final String[] overflowTags = {"test3", "4overflow", "test0"};

		final long overflowToken0 = session.binderTransactionStarting(overflowTags[0]);
		session.binderTransactionStarting(overflowTags[0]);
		final long overflowToken1 = session.binderTransactionStarting(overflowTags[1]);
		final long overflowToken2 = session.binderTransactionStarting(overflowTags[2]);
		session.binderTransactionStarting(overflowTags[2]);

		assertTrue(session.mKeyByTag.containsKey(OVERFLOW_TAG));
		assertEquals(MAX_UNIQUE_TAGS + 1, session.mCountByKey.size());
		assertEquals(MAX_UNIQUE_TAGS + 1, session.mKeyByTag.size());
		assertEquals(5, session.mCountByKey.get(MAX_UNIQUE_TAGS));
		for (final String overflowTag : overflowTags) {
		assertFalse(session.mKeyByTag.containsKey(overflowTag));
		}

		for (int i = 0; i < MAX_UNIQUE_TAGS; i++) {
		final String tag = uniqueTags.get(i);
		session.binderTransactionStarting(tag);
		assertEquals(2, session.mCountByKey.get(i));
		assertEquals(5, session.mCountByKey.get(MAX_UNIQUE_TAGS));
		}

		session.binderTransactionCompleted(overflowToken0);
		session.binderTransactionCompleted(overflowToken1);
		session.binderTransactionCompleted(overflowToken2);
		assertEquals(2, session.mCountByKey.get(MAX_UNIQUE_TAGS));
		for (int i = 0; i < MAX_UNIQUE_TAGS; i++) {
		assertEquals(2, session.mCountByKey.get(i));
		}
		}
		}