1/*
2 * Copyright (C) 2008 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
17package com.android.internal.os;
18
19import android.os.IBinder;
20import android.os.SystemClock;
21import android.util.EventLog;
22
23import dalvik.system.VMRuntime;
24
25import java.lang.ref.WeakReference;
26import java.util.ArrayList;
27
28/**
29 * Private and debugging Binder APIs.
30 *
31 * @see IBinder
32 */
33public class BinderInternal {
34    static WeakReference<GcWatcher> sGcWatcher
35            = new WeakReference<GcWatcher>(new GcWatcher());
36    static ArrayList<Runnable> sGcWatchers = new ArrayList<>();
37    static Runnable[] sTmpWatchers = new Runnable[1];
38    static long sLastGcTime;
39
40    static final class GcWatcher {
41        @Override
42        protected void finalize() throws Throwable {
43            handleGc();
44            sLastGcTime = SystemClock.uptimeMillis();
45            synchronized (sGcWatchers) {
46                sTmpWatchers = sGcWatchers.toArray(sTmpWatchers);
47            }
48            for (int i=0; i<sTmpWatchers.length; i++) {
49                if (sTmpWatchers[i] != null) {
50                    sTmpWatchers[i].run();
51                }
52            }
53            sGcWatcher = new WeakReference<GcWatcher>(new GcWatcher());
54        }
55    }
56
57    public static void addGcWatcher(Runnable watcher) {
58        synchronized (sGcWatchers) {
59            sGcWatchers.add(watcher);
60        }
61    }
62
63    /**
64     * Add the calling thread to the IPC thread pool.  This function does
65     * not return until the current process is exiting.
66     */
67    public static final native void joinThreadPool();
68
69    /**
70     * Return the system time (as reported by {@link SystemClock#uptimeMillis
71     * SystemClock.uptimeMillis()}) that the last garbage collection occurred
72     * in this process.  This is not for general application use, and the
73     * meaning of "when a garbage collection occurred" will change as the
74     * garbage collector evolves.
75     *
76     * @return Returns the time as per {@link SystemClock#uptimeMillis
77     * SystemClock.uptimeMillis()} of the last garbage collection.
78     */
79    public static long getLastGcTime() {
80        return sLastGcTime;
81    }
82
83    /**
84     * Return the global "context object" of the system.  This is usually
85     * an implementation of IServiceManager, which you can use to find
86     * other services.
87     */
88    public static final native IBinder getContextObject();
89
90    /**
91     * Special for system process to not allow incoming calls to run at
92     * background scheduling priority.
93     * @hide
94     */
95    public static final native void disableBackgroundScheduling(boolean disable);
96
97    public static final native void setMaxThreads(int numThreads);
98
99    static native final void handleGc();
100
101    public static void forceGc(String reason) {
102        EventLog.writeEvent(2741, reason);
103        VMRuntime.getRuntime().requestConcurrentGC();
104    }
105
106    static void forceBinderGc() {
107        forceGc("Binder");
108    }
109}
110