Merge changes I78cd6a32,I99656d57 into tm-dev (c16c6a2a) · Commits · e / os / android_frameworks_base

services/core/java/com/android/server/pm/Computer.java

+3 −2

Original line number	Diff line number	Diff line
		@@ -94,12 +94,13 @@ import java.util.Set;
		@VisibleForTesting(visibility = VisibleForTesting.Visibility.PRIVATE)
		public interface Computer extends PackageDataSnapshot {

		int getVersion();

		/**
		* Administrative statistics: record that the snapshot has been used. Every call
		* to use() increments the usage counter.
		*/
		default void use() {
		}
		Computer use();
		/**
		* Fetch the snapshot usage counter.
		* @return The number of times this snapshot was used.

services/core/java/com/android/server/pm/ComputerEngine.java

+11 −2

Original line number	Diff line number	Diff line
		@@ -367,6 +367,8 @@ public class ComputerEngine implements Computer {
		return (v1 > v2) ? -1 : ((v1 < v2) ? 1 : 0);
		};

		private final int mVersion;

		// The administrative use counter.
		private int mUsed = 0;

		@@ -424,7 +426,8 @@ public class ComputerEngine implements Computer {
		return mLocalAndroidApplication;
		}

		ComputerEngine(PackageManagerService.Snapshot args) {
		ComputerEngine(PackageManagerService.Snapshot args, int version) {
		mVersion = version;
		mSettings = new Settings(args.settings);
		mIsolatedOwners = args.isolatedOwners;
		mPackages = args.packages;
		@@ -464,11 +467,17 @@ public class ComputerEngine implements Computer {
		mService = args.service;
		}

		@Override
		public int getVersion() {
		return mVersion;
		}

		/**
		* Record that the snapshot was used.
		*/
		public final void use() {
		public final Computer use() {
		mUsed++;
		return this;
		}

		/**

services/core/java/com/android/server/pm/ComputerLocked.java

+1 −1

Original line number	Diff line number	Diff line
		@@ -30,7 +30,7 @@ import com.android.internal.annotations.VisibleForTesting;
		public final class ComputerLocked extends ComputerEngine {

		ComputerLocked(PackageManagerService.Snapshot args) {
		super(args);
		super(args, -1);
		}

		protected ComponentName resolveComponentName() {

services/core/java/com/android/server/pm/PackageManagerService.java

+63 −58

Original line number	Diff line number	Diff line
		@@ -271,8 +271,8 @@ import java.util.Set;
		import java.util.concurrent.Executor;
		import java.util.concurrent.Future;
		import java.util.concurrent.TimeUnit;
		import java.util.concurrent.atomic.AtomicBoolean;
		import java.util.concurrent.atomic.AtomicInteger;
		import java.util.concurrent.atomic.AtomicReference;
		import java.util.function.Consumer;

		/**
		@@ -1038,22 +1038,15 @@ public class PackageManagerService implements PackageSender, TestUtilityService
		// times during the PackageManagerService constructor but it should not be modified thereafter.
		private ComputerLocked mLiveComputer;

		// A lock-free cache for frequently called functions.
		private volatile Computer mSnapshotComputer;
		private static final AtomicReference<Computer> sSnapshot = new AtomicReference<>();

		// If true, the snapshot is invalid (stale). The attribute is static since it may be
		// set from outside classes. The attribute may be set to true anywhere, although it
		// should only be set true while holding mLock. However, the attribute id guaranteed
		// to be set false only while mLock and mSnapshotLock are both held.
		private static final AtomicBoolean sSnapshotInvalid = new AtomicBoolean(true);

		static final ThreadLocal<ThreadComputer> sThreadComputer =
		ThreadLocal.withInitial(ThreadComputer::new);
		// If this differs from Computer#getVersion, the snapshot is invalid (stale).
		private static final AtomicInteger sSnapshotPendingVersion = new AtomicInteger(1);

		/**
		* This lock is used to make reads from {@link #sSnapshotInvalid} and
		* {@link #mSnapshotComputer} atomic inside {@code snapshotComputer()}. This lock is
		* not meant to be used outside that method. This lock must be taken before
		* This lock is used to make reads from {@link #sSnapshotPendingVersion} and
		* {@link #sSnapshot} atomic inside {@code snapshotComputer()} when the versions mismatch.
		* This lock is not meant to be used outside that method. This lock must be taken before
		* {@link #mLock} is taken.
		*/
		private final Object mSnapshotLock = new Object();
		@@ -1077,48 +1070,53 @@ public class PackageManagerService implements PackageSender, TestUtilityService
		// yet invalidated the snapshot. Always give the thread the live computer.
		return mLiveComputer;
		}

		var oldSnapshot = sSnapshot.get();
		var pendingVersion = sSnapshotPendingVersion.get();

		if (oldSnapshot != null && oldSnapshot.getVersion() == pendingVersion) {
		return oldSnapshot.use();
		}

		synchronized (mSnapshotLock) {
		// This synchronization block serializes access to the snapshot computer and
		// to the code that samples mSnapshotInvalid.
		Computer c = mSnapshotComputer;
		if (sSnapshotInvalid.getAndSet(false) \|\| (c == null)) {
		// The snapshot is invalid if it is marked as invalid or if it is null. If it
		// is null, then it is currently being rebuilt by rebuildSnapshot().
		synchronized (mLock) {
		// Rebuild the snapshot if it is invalid. Note that the snapshot might be
		// invalidated as it is rebuilt. However, the snapshot is still
		// self-consistent (the lock is being held) and is current as of the time
		// this function is entered.
		rebuildSnapshot();
		// Re-capture pending version in case a new invalidation occurred since last check
		var rebuildSnapshot = sSnapshot.get();
		var rebuildVersion = sSnapshotPendingVersion.get();

		// Guaranteed to be non-null. mSnapshotComputer is only be set to null
		// temporarily in rebuildSnapshot(), which is guarded by mLock(). Since
		// the mLock is held in this block and since rebuildSnapshot() is
		// complete, the attribute can not now be null.
		c = mSnapshotComputer;
		// Check the versions again while the lock is held, in case the rebuild time caused
		// multiple threads to wait on the snapshot lock. When the first thread finishes
		// a rebuild, the snapshot is now valid and the other waiting threads can use it
		// without kicking off their own rebuilds.
		if (rebuildSnapshot != null && rebuildSnapshot.getVersion() == rebuildVersion) {
		return rebuildSnapshot.use();
		}

		synchronized (mLock) {
		// Fetch version one last time to ensure that the rebuilt snapshot matches
		// the latest invalidation, which could have come in between entering the
		// SnapshotLock and mLock sync blocks.
		rebuildVersion = sSnapshotPendingVersion.get();

		// Build the snapshot for this version
		var newSnapshot = rebuildSnapshot(rebuildSnapshot, rebuildVersion);
		sSnapshot.set(newSnapshot);
		return newSnapshot.use();
		}
		c.use();
		return c;
		}
		}

		/**
		* Rebuild the cached computer. mSnapshotComputer is temporarily set to null to block other
		* threads from using the invalid computer until it is rebuilt.
		*/
		@GuardedBy({ "mLock", "mSnapshotLock"})
		private void rebuildSnapshot() {
		final long now = SystemClock.currentTimeMicro();
		final int hits = mSnapshotComputer == null ? -1 : mSnapshotComputer.getUsed();
		mSnapshotComputer = null;
		final Snapshot args = new Snapshot(Snapshot.SNAPPED);
		mSnapshotComputer = new ComputerEngine(args);
		final long done = SystemClock.currentTimeMicro();
		private Computer rebuildSnapshot(@Nullable Computer oldSnapshot, int newVersion) {
		var now = SystemClock.currentTimeMicro();
		var hits = oldSnapshot == null ? -1 : oldSnapshot.getUsed();
		var args = new Snapshot(Snapshot.SNAPPED);
		var newSnapshot = new ComputerEngine(args, newVersion);
		var done = SystemClock.currentTimeMicro();

		if (mSnapshotStatistics != null) {
		mSnapshotStatistics.rebuild(now, done, hits);
		}
		return newSnapshot;
		}

		/**
		@@ -1138,7 +1136,7 @@ public class PackageManagerService implements PackageSender, TestUtilityService
		if (TRACE_SNAPSHOTS) {
		Log.i(TAG, "snapshot: onChange(" + what + ")");
		}
		sSnapshotInvalid.set(true);
		sSnapshotPendingVersion.incrementAndGet();
		}

		/**
		@@ -1665,7 +1663,6 @@ public class PackageManagerService implements PackageSender, TestUtilityService
		mRequiredSdkSandboxPackage = testParams.requiredSdkSandboxPackage;

		mLiveComputer = createLiveComputer();
		mSnapshotComputer = null;
		mSnapshotStatistics = null;

		mPackages.putAll(testParams.packages);
		@@ -1855,9 +1852,8 @@ public class PackageManagerService implements PackageSender, TestUtilityService
		// cached computer is the same as the live computer until the end of the
		// constructor, at which time the invalidation method updates it.
		mSnapshotStatistics = new SnapshotStatistics();
		sSnapshotInvalid.set(true);
		sSnapshotPendingVersion.incrementAndGet();
		mLiveComputer = createLiveComputer();
		mSnapshotComputer = null;
		registerObservers(true);
		}

		@@ -5388,10 +5384,8 @@ public class PackageManagerService implements PackageSender, TestUtilityService
		@Override
		public void setApplicationCategoryHint(String packageName, int categoryHint,
		String callerPackageName) {
		final PackageStateMutator.InitialState initialState = recordInitialState();

		final FunctionalUtils.ThrowingFunction<Computer, PackageStateMutator.Result>
		implementation = computer -> {
		final FunctionalUtils.ThrowingBiFunction<PackageStateMutator.InitialState, Computer,
		PackageStateMutator.Result> implementation = (initialState, computer) -> {
		if (computer.getInstantAppPackageName(Binder.getCallingUid()) != null) {
		throw new SecurityException(
		"Instant applications don't have access to this method");
		@@ -5419,12 +5413,13 @@ public class PackageManagerService implements PackageSender, TestUtilityService
		}
		};

		PackageStateMutator.Result result = implementation.apply(snapshotComputer());
		PackageStateMutator.Result result =
		implementation.apply(recordInitialState(), snapshotComputer());
		if (result != null && result.isStateChanged() && !result.isSpecificPackageNull()) {
		// TODO: Specific return value of what state changed?
		// The installer on record might have changed, retry with lock
		synchronized (mPackageStateWriteLock) {
		result = implementation.apply(snapshotComputer());
		result = implementation.apply(recordInitialState(), snapshotComputer());
		}
		}

		@@ -7156,9 +7151,19 @@ public class PackageManagerService implements PackageSender, TestUtilityService
		public PackageStateMutator.Result commitPackageStateMutation(
		@Nullable PackageStateMutator.InitialState initialState, @NonNull String packageName,
		@NonNull Consumer<PackageStateWrite> consumer) {
		PackageStateMutator.Result result = null;
		if (Thread.holdsLock(mPackageStateWriteLock)) {
		// If the thread is already holding the lock, this is likely a retry based on a prior
		// failure, and re-calculating whether a state change occurred can be skipped.
		result = PackageStateMutator.Result.SUCCESS;
		}
		synchronized (mPackageStateWriteLock) {
		final PackageStateMutator.Result result = mPackageStateMutator.generateResult(
		if (result == null) {
		// If the thread wasn't previously holding, this is a first-try commit and so a
		// state change may have happened.
		result = mPackageStateMutator.generateResult(
		initialState, mChangedPackagesTracker.getSequenceNumber());
		}
		if (result != PackageStateMutator.Result.SUCCESS) {
		return result;
		}

services/core/java/com/android/server/pm/ThreadComputer.java

deleted100644 → 0

+0 −52

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2021 The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		* You may obtain a copy of the License at
		*
		* http://www.apache.org/licenses/LICENSE-2.0
		*
		* Unless required by applicable law or agreed to in writing, software
		* distributed under the License is distributed on an "AS IS" BASIS,
		* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
		* See the License for the specific language governing permissions and
		* limitations under the License.
		*/

		package com.android.server.pm;

		/**
		* This class records the Computer being used by a thread and the Computer's reference
		* count. There is a thread-local copy of this class.
		*/
		public final class ThreadComputer implements AutoCloseable {
		Computer mComputer = null;
		int mRefCount = 0;

		void acquire(Computer c) {
		if (mRefCount != 0 && mComputer != c) {
		throw new RuntimeException("computer mismatch, count = " + mRefCount);
		}
		mComputer = c;
		mRefCount++;
		}

		void acquire() {
		if (mRefCount == 0 \|\| mComputer == null) {
		throw new RuntimeException("computer acquire on empty ref count");
		}
		mRefCount++;
		}

		void release() {
		if (--mRefCount == 0) {
		mComputer = null;
		}
		}

		@Override
		public void close() {
		release();
		}
		}