1 /* 2 * Copyright (C) 2022 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 package com.android.server.wm; 17 18 import android.annotation.Nullable; 19 import android.hardware.HardwareBuffer; 20 import android.util.ArrayMap; 21 import android.window.TaskSnapshot; 22 23 import com.android.internal.annotations.GuardedBy; 24 25 import java.io.PrintWriter; 26 import java.util.function.Consumer; 27 28 /** 29 * Base class for an app snapshot cache 30 * @param <TYPE> The basic type, either Task or ActivityRecord 31 */ 32 abstract class SnapshotCache<TYPE extends WindowContainer> { 33 protected final Object mLock = new Object(); 34 35 protected final String mName; 36 37 @GuardedBy("mLock") 38 protected final ArrayMap<ActivityRecord, Integer> mAppIdMap = new ArrayMap<>(); 39 40 @GuardedBy("mLock") 41 protected final ArrayMap<Integer, CacheEntry> mRunningCache = new ArrayMap<>(); 42 43 protected Consumer<HardwareBuffer> mSafeSnapshotReleaser; 44 SnapshotCache(String name)45 SnapshotCache(String name) { 46 mName = name; 47 } 48 putSnapshot(TYPE window, TaskSnapshot snapshot)49 abstract void putSnapshot(TYPE window, TaskSnapshot snapshot); 50 setSafeSnapshotReleaser(Consumer<HardwareBuffer> safeSnapshotReleaser)51 void setSafeSnapshotReleaser(Consumer<HardwareBuffer> safeSnapshotReleaser) { 52 mSafeSnapshotReleaser = safeSnapshotReleaser; 53 } 54 clearRunningCache()55 void clearRunningCache() { 56 synchronized (mLock) { 57 mRunningCache.clear(); 58 } 59 } 60 61 @Nullable getSnapshotInner(Integer id)62 final TaskSnapshot getSnapshotInner(Integer id) { 63 synchronized (mLock) { 64 // Try the running cache. 65 final CacheEntry entry = mRunningCache.get(id); 66 if (entry != null) { 67 return entry.snapshot; 68 } 69 } 70 return null; 71 } 72 73 /** Called when an app token has been removed. */ onAppRemoved(ActivityRecord activity)74 void onAppRemoved(ActivityRecord activity) { 75 synchronized (mLock) { 76 final Integer id = mAppIdMap.get(activity); 77 if (id != null) { 78 removeRunningEntry(id); 79 } 80 } 81 } 82 83 /** Called when an app window token's process died. */ onAppDied(ActivityRecord activity)84 void onAppDied(ActivityRecord activity) { 85 synchronized (mLock) { 86 final Integer id = mAppIdMap.get(activity); 87 if (id != null) { 88 removeRunningEntry(id); 89 } 90 } 91 } 92 onIdRemoved(Integer index)93 void onIdRemoved(Integer index) { 94 removeRunningEntry(index); 95 } 96 removeRunningEntry(Integer id)97 void removeRunningEntry(Integer id) { 98 synchronized (mLock) { 99 final CacheEntry entry = mRunningCache.get(id); 100 if (entry != null) { 101 mAppIdMap.remove(entry.topApp); 102 mRunningCache.remove(id); 103 entry.snapshot.removeReference(TaskSnapshot.REFERENCE_CACHE); 104 } 105 } 106 } 107 dump(PrintWriter pw, String prefix)108 void dump(PrintWriter pw, String prefix) { 109 final String doublePrefix = prefix + " "; 110 final String triplePrefix = doublePrefix + " "; 111 pw.println(prefix + "SnapshotCache " + mName); 112 113 synchronized (mLock) { 114 for (int i = mRunningCache.size() - 1; i >= 0; i--) { 115 final CacheEntry entry = mRunningCache.valueAt(i); 116 pw.println(doublePrefix + "Entry token=" + mRunningCache.keyAt(i)); 117 pw.println(triplePrefix + "topApp=" + entry.topApp); 118 pw.println(triplePrefix + "snapshot=" + entry.snapshot); 119 } 120 } 121 } 122 123 static final class CacheEntry { 124 /** The snapshot. */ 125 final TaskSnapshot snapshot; 126 /** The app token that was on top of the task when the snapshot was taken */ 127 final ActivityRecord topApp; CacheEntry(TaskSnapshot snapshot, ActivityRecord topApp)128 CacheEntry(TaskSnapshot snapshot, ActivityRecord topApp) { 129 this.snapshot = snapshot; 130 this.topApp = topApp; 131 } 132 } 133 } 134