Fyodor Kupolov | e29a5a1 | 2016-12-16 16:14:17 -0800 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (C) 2016 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 | |
| 17 | package com.android.server; |
| 18 | |
| 19 | import android.os.Build; |
| 20 | import android.os.Process; |
| 21 | import android.util.Slog; |
| 22 | |
| 23 | import com.android.internal.util.ConcurrentUtils; |
| 24 | import com.android.internal.util.Preconditions; |
| 25 | |
| 26 | import java.util.List; |
| 27 | import java.util.concurrent.Callable; |
| 28 | import java.util.concurrent.ExecutorService; |
| 29 | import java.util.concurrent.Future; |
| 30 | import java.util.concurrent.TimeUnit; |
| 31 | |
| 32 | /** |
| 33 | * Thread pool used during initialization of system server. |
| 34 | * <p>System services can {@link #submit(Runnable)} tasks for execution during boot. |
| 35 | * The pool will be shut down after {@link SystemService#PHASE_BOOT_COMPLETED}. |
| 36 | * New tasks <em>should not</em> be submitted afterwards. |
| 37 | * |
| 38 | * @hide |
| 39 | */ |
| 40 | public class SystemServerInitThreadPool { |
| 41 | private static final String TAG = SystemServerInitThreadPool.class.getSimpleName(); |
| 42 | private static final int SHUTDOWN_TIMEOUT_MILLIS = 20000; |
| 43 | private static final boolean IS_DEBUGGABLE = Build.IS_DEBUGGABLE; |
| 44 | |
| 45 | private static SystemServerInitThreadPool sInstance; |
| 46 | |
| 47 | private ExecutorService mService = ConcurrentUtils.newFixedThreadPool(2, |
| 48 | "system-server-init-thread", Process.THREAD_PRIORITY_FOREGROUND); |
| 49 | |
| 50 | public static synchronized SystemServerInitThreadPool get() { |
| 51 | if (sInstance == null) { |
| 52 | sInstance = new SystemServerInitThreadPool(); |
| 53 | } |
| 54 | Preconditions.checkState(sInstance.mService != null, "Cannot get " + TAG |
| 55 | + " - it has been shut down"); |
| 56 | return sInstance; |
| 57 | } |
| 58 | |
| 59 | public Future<?> submit(Runnable runnable, String description) { |
| 60 | if (IS_DEBUGGABLE) { |
| 61 | return mService.submit(() -> { |
| 62 | Slog.d(TAG, "Started executing " + description); |
| 63 | try { |
| 64 | runnable.run(); |
| 65 | } catch (RuntimeException e) { |
| 66 | Slog.e(TAG, "Failure in " + description + ": " + e, e); |
| 67 | throw e; |
| 68 | } |
| 69 | Slog.d(TAG, "Finished executing " + description); |
| 70 | }); |
| 71 | } |
| 72 | return mService.submit(runnable); |
| 73 | } |
| 74 | |
| 75 | static synchronized void shutdown() { |
| 76 | if (sInstance != null && sInstance.mService != null) { |
| 77 | sInstance.mService.shutdown(); |
| 78 | boolean terminated; |
| 79 | try { |
| 80 | terminated = sInstance.mService.awaitTermination(SHUTDOWN_TIMEOUT_MILLIS, |
| 81 | TimeUnit.MILLISECONDS); |
| 82 | } catch (InterruptedException e) { |
| 83 | Thread.currentThread().interrupt(); |
| 84 | throw new IllegalStateException(TAG + " init interrupted"); |
| 85 | } |
| 86 | List<Runnable> unstartedRunnables = sInstance.mService.shutdownNow(); |
| 87 | if (!terminated) { |
| 88 | throw new IllegalStateException("Cannot shutdown. Unstarted tasks " |
| 89 | + unstartedRunnables); |
| 90 | } |
| 91 | sInstance.mService = null; // Make mService eligible for GC |
| 92 | Slog.d(TAG, "Shutdown successful"); |
| 93 | } |
| 94 | } |
| 95 | |
| 96 | } |