1. SystemServer启动简介

“ SystemServer的在Android体系中所处的地位，SystemServer由Zygote fork生成的，是zygote孵化出的第一个进程，该进程是从ZygoteInit.java的main()函数中调用 startSystemServer()开始的。与启动普通进程的差别在于，zygote类为启动SystemServer提供了专门的函数 startSystemServer()，而不是使用标准的forAndSpecilize()函数，同时，SystemServer进程启动后首先要做的事情和普通进程也有所差别。”

Zygote不是很熟，其实我只要知道SystemSever是由Zygote启动起来，启动后就会调用自己的main()方法就好了，这是我关注的重点。

2. SystemServer重要功能梳理

我们知道systemserver启动后的入口是自己的main()方法，那就从这里开始吧~

2.1 main

    /**     * The main entry point from zygote.     */    public static void main(String[] args) {        new SystemServer().run();    }

没啥好看的，继续看run()方法

2.2 run

方法体比较长，只选择重要的梳理

    public SystemServer() {        // Check for factory test mode.        mFactoryTestMode = FactoryTest.getMode();        // Remember if it's runtime restart(when sys.boot_completed is already set) or reboot        mRuntimeRestart = "1".equals(SystemProperties.get("sys.boot_completed"));    }    private void run() {        try {            traceBeginAndSlog("InitBeforeStartServices");            // If a device's clock is before 1970 (before 0), a lot of            // APIs crash dealing with negative numbers, notably            // java.io.File#setLastModified, so instead we fake it and            // hope that time from cell towers or NTP fixes it shortly.            if (System.currentTimeMillis() < EARLIEST_SUPPORTED_TIME) {                Slog.w(TAG, "System clock is before 1970; setting to 1970.");                SystemClock.setCurrentTimeMillis(EARLIEST_SUPPORTED_TIME);            }            //            // Default the timezone property to GMT if not set.            //            String timezoneProperty =  SystemProperties.get("persist.sys.timezone");            if (timezoneProperty == null || timezoneProperty.isEmpty()) {                Slog.w(TAG, "Timezone not set; setting to GMT.");                SystemProperties.set("persist.sys.timezone", "GMT");            }            // If the system has "persist.sys.language" and friends set, replace them with            // "persist.sys.locale". Note that the default locale at this point is calculated            // using the "-Duser.locale" command line flag. That flag is usually populated by            // AndroidRuntime using the same set of system properties, but only the system_server            // and system apps are allowed to set them.            //            // NOTE: Most changes made here will need an equivalent change to            // core/jni/AndroidRuntime.cpp            if (!SystemProperties.get("persist.sys.language").isEmpty()) {                final String languageTag = Locale.getDefault().toLanguageTag();                SystemProperties.set("persist.sys.locale", languageTag);                SystemProperties.set("persist.sys.language", "");                SystemProperties.set("persist.sys.country", "");                SystemProperties.set("persist.sys.localevar", "");            }            // The system server should never make non-oneway calls            Binder.setWarnOnBlocking(true);            // Here we go!            Slog.i(TAG, "Entered the Android system server!");            int uptimeMillis = (int) SystemClock.elapsedRealtime();            EventLog.writeEvent(EventLogTags.BOOT_PROGRESS_SYSTEM_RUN, uptimeMillis);            if (!mRuntimeRestart) {                MetricsLogger.histogram(null, "boot_system_server_init", uptimeMillis);            }            // In case the runtime switched since last boot (such as when            // the old runtime was removed in an OTA), set the system            // property so that it is in sync. We can | xq oqi't do this in            // libnativehelper's JniInvocation::Init code where we already            // had to fallback to a different runtime because it is            // running as root and we need to be the system user to set            // the property. http://b/11463182            SystemProperties.set("persist.sys.dalvik.vm.lib.2", VMRuntime.getRuntime().vmLibrary());            // Mmmmmm... more memory!            VMRuntime.getRuntime().clearGrowthLimit();            // The system server has to run all of the time, so it needs to be            // as efficient as possible with its memory usage.            VMRuntime.getRuntime().setTargetHeapUtilization(0.8f);            // Some devices rely on runtime fingerprint generation, so make sure            // we've defined it before booting further.            Build.ensureFingerprintProperty();            // Within the system server, it is an error to access Environment paths without            // explicitly specifying a user.            Environment.setUserRequired(true);            // Within the system server, any incoming Bundles should be defused            // to avoid throwing BadParcelableException.            BaseBundle.setShouldDefuse(true);            // Ensure binder calls into the system always run at foreground priority.            BinderInternal.disableBackgroundScheduling(true);            // Increase the number of binder threads in system_server            BinderInternal.setMaxThreads(sMaxBinderThreads);            // Prepare the main looper thread (this thread).            android.os.Process.setThreadPriority(                android.os.Process.THREAD_PRIORITY_FOREGROUND);            android.os.Process.setCanSelfBackground(false);            Looper.prepareMainLooper();            // Initialize native services.            System.loadLibrary("android_servers");            // Check whether we failed to shut down last time we tried.            // This call may not return.            performPendingShutdown();            // Initialize the system context.            createSystemContext();            // Create the system service manager.            mSystemServiceManager = new SystemServiceManager(mSystemContext);            mSystemServiceManager.setRuntimeRestarted(mRuntimeRestart);            LocalServices.addService(SystemServiceManager.class, mSystemServiceManager);            // Prepare the thread pool for init tasks that can be parallelized            SystemServerInitThreadPool.get();        } finally {            traceEnd();  // InitBeforeStartServices        }        // Start services.        try {            traceBeginAndSlog("StartServices");            startBootstrapServices();            startCoreServices();            startOtherServices();            SystemServerInitThreadPool.shutdown();        } catch (Throwable ex) {            Slog.e("System", "******************************************");            Slog.e("System", "************ Failure starting system services", ex);            throw ex;        } finally {            traceEnd();        }        // For debug builds, log event loop stalls to dropbox for analysis.        if (StrictMode.conditionallyEnableDebugLogging()) {            Slog.i(TAG, "Enabled StrictMode for system server main thread.");        }        if (!mRuntimeRestart && !isFirstBootOrUpgrade()) {            int uptimeMillis = (int) SystemClock.elapsedRealtime();            MetricsLogger.histogram(null, "boot_system_server_ready", uptimeMillis);            final int MAX_UPTIME_MILLIS = 60 * 1000;            if (uptimeMillis > MAX_UPTIME_MILLIS) {                Slog.wtf(SYSTEM_SERVER_TIMING_TAG,                        "SystemServer init took too long. uptimeMillis=" + uptimeMillis);            }        }        // Loop forever.        Looper.loop();        throw new RuntimeException("Main thread loop unexpectedly exited");    }

有点长，但是基本来看逻辑方面的不多，主要是一些配置项，依据参考文章和自己的看法挑比较重要的梳理下。

2.2.1 createSystemContext

简单梳理下代码流程

    private void createSystemContext() {        ActivityThread activityThread = ActivityThread.systemMain();        mSystemContext = activityThread.getSystemContext();        mSystemContext.setTheme(DEFAULT_SYSTEM_THEME);        final Context systemUiContext = activityThread.getSystemUiContext();        systemUiContext.setTheme(DEFAULT_SYSTEM_THEME);    }    public ContextImpl getSystemContext() {        synchronized (this) {            if (mSystemContext == null) {                mSystemContext = ContextImpl.createSystemContext(this);            }            return mSystemContext;        }    }    static ContextImpl createSystemContext(ActivityThread mainThread) {        LoadedApk loadedApk = new LoadedApk(mainThread);        ContextImpl context = new ContextImpl(null, mainThread, loadedApk, null, null, null, 0,                null);        context.setResources(loadedApk.getResources());        context.mResources.updateConfiguration(context.mResourcesManager.getConfiguration(),                context.mResourcesManager.getDisplayMetrics());        return context;    }

其中看下ActivityThread.systemMain()会调用到如下方法中去：

           try {                mInstrumentation = new Instrumentation();                ContextImpl context = ContextImpl.createAppContext(                        this, getSystemContext().mLoadedApk);                mInitialApplication = context.mLoadedApk.makeApplication(true, null);                mInitialApplication.onCreate();            } catch (Exception e) {                throw new RuntimeException(                        "Unable to instantiate Application():" + e.toString(), e);            }

这里用ContextImpl.createAppContext()创建一个ContextImpl，接着调用context.mPackageInfo.makeApplication(true, null)创建该应用的Application对象，并调用该Application的onCreate()方法：这里启动了一个包名为android的系统应用程序。

2.2.2 SystemServiceManager

            // Create the system service manager.            mSystemServiceManager = new SystemServiceManager(mSystemContext);            mSystemServiceManager.setRuntimeRestarted(mRuntimeRestart);            LocalServices.addService(SystemServiceManager.class, mSystemServiceManager);

初始化SystemServierManager，观察到它有如下方法，说明这个类是用来负责启动Service的。

   /**     * Starts a service by class name.     *     * @return The service instance.     */    @SuppressWarnings("unchecked")    public SystemService startService(String className) {        final Class serviceClass;        try {            serviceClass = (Class)Class.forName(className);        } catch (ClassNotFoundException ex) {            Slog.i(TAG, "Starting " + className);            throw new RuntimeException("Failed to create service " + className                    + ": service class not found, usually indicates that the caller should "                    + "have called PackageManager.hasSystemFeature() to check whether the "                    + "feature is available on this device before trying to start the "                    + "services that implement it", ex);        }        return startService(serviceClass);    }

2.2.3 startBootstrapServices

里面有我稍微熟悉一点的StartActivityManager和StartPackageManagerService，也就是说am和pm就是在这个方法里被启动起来的。

    /**     * Starts the small tangle of critical services that are needed to get     * the system off the ground.  These services have complex mutual dependencies     * which is why we initialize them all in one place here.  Unless your service     * is also entwined in these dependencies, it should be initialized in one of     * the other functions.     */    private void startBootstrapServices() {        Slog.i(TAG, "Reading configuration...");        final String TAG_SYSTEM_CONFIG = "ReadingSystemConfig";        traceBeginAndSlog(TAG_SYSTEM_CONFIG);        SystemServerInitThreadPool.get().submit(SystemConfig::getInstance, TAG_SYSTEM_CONFIG);        traceEnd();        // Wait for installd to finish starting up so that it has a chance to        // create critical directories such as /data/user with the appropriate        // permissions.  We need this to complete before we initialize other services.        traceBeginAndSlog("StartInstaller");        Installer installer = mSystemServiceManager.startService(Installer.class);        traceEnd();        // In some cases after launching an app we need to access device identifiers,        // therefore register the device identifier policy before the activity manager.        traceBeginAndSlog("DeviceIdentifiersPolicyService");        mSystemServiceManager.startService(DeviceIdentifiersPolicyService.class);        traceEnd();        // Activity manager runs the show.        traceBeginAndSlog("StartActivityManager");        mActivityManagerService = mSystemServiceManager.startService(                ActivityManagerService.Lifecycle.class).getService();        mActivityManagerService.setSystemServiceManager(mSystemServiceManager);        mActivityManagerService.setInstaller(installer);        traceEnd();        // Power manager needs to be started early because other services need it.        // Native daemons may be watching for it to be registered so it must be ready        // to handle incoming binder calls immediately (including being able to verify        // the permissions for those calls).        traceBeginAndSlog("StartPowerManager");        mPowerManagerService = mSystemServiceManager.startService(PowerManagerService.class);        traceEnd();        // Now that the power manager has been started, let the activity manager        // initialize power management features.        traceBeginAndSlog("InitPowerManagement");        mActivityManagerService.initPowerManagement();        traceEnd();        // Bring up recovery system in case a rescue party needs a reboot        if (!SystemProperties.getBoolean("config.disable_noncore", false)) {            traceBeginAndSlog("StartRecoverySystemService");            mSystemServiceManager.startService(RecoverySystemService.class);            traceEnd();        }        // Now that we have the bare essentials of the OS up and running, take        // note that we just booted, which might send out a rescue party if        // we're stuck in a runtime restart loop.        RescueParty.noteBoot(mSystemContext);        // Manages LEDs and display backlight so we need it to bring up the display.        traceBeginAndSlog("StartLightsService");        mSystemServiceManager.startService(LightsService.class);        traceEnd();        // Display manager is needed to provide display metrics before package manager        // starts up.        traceBeginAndSlog("StartDisplayManager");        mDisplayManagerService = mSystemServiceManager.startService(DisplayManagerService.class);        traceEnd();        // We need the default display before we can initialize the package manager.        traceBeginAndSlog("WaitForDisplay");        mSystemServiceManager.startBootPhase(SystemService.PHASE_WAIT_FOR_DEFAULT_DISPLAY);        traceEnd();        // Only run "core" apps if we're encrypting the device.        String cryptState = SystemProperties.get("vold.decrypt");        if (ENCRYPTING_STATE.equals(cryptState)) {            Slog.w(TAG, "Detected encryption in progress - only parsing core apps");            mOnlyCore = true;        } else if (ENCRYPTED_STATE.equals(cryptState)) {            Slog.w(TAG, "Device encrypted - only parsing core apps");            mOnlyCore = true;        }        // Start the package manager.        if (!mRuntimeRestart) {            MetricsLogger.histogram(null, "boot_package_manager_init_start",                    (int) SystemClock.elapsedRealtime());        }        traceBeginAndSlog("StartPackageManagerService");        mPackageManagerService = PackageManagerService.main(mSystemContext, installer,                mFactoryTestMode != FactoryTest.FACTORY_TEST_OFF, mOnlyCore);        mFirstBoot = mPackageManagerService.isFirstBoot();        mPackageManager = mSystemContext.getPackageManager();        traceEnd();        if (!mRuntimeRestart && !isFirstBootOrUpgrade()) {            MetricsLogger.histogram(null, "boot_package_manager_init_ready",                    (int) SystemClock.elapsedRealtime());        }        // Manages A/B OTA dexopting. This is a bootstrap service as we need it to rename        // A/B artifacts after boot, before anything else might touch/need them.        // Note: this isn't needed during decryption (we don't have /data anyways).        if (!mOnlyCore) {            boolean disableOtaDexopt = SystemProperties.getBoolean("config.disable_otadexopt",                    false);            if (!disableOtaDexopt) {                traceBeginAndSlog("StartOtaDexOptService");                try {                    OtaDexoptService.main(mSystemContext, mPackageManagerService);                } catch (Throwable e) {                    reportWtf("starting OtaDexOptService", e);                } finally {                    traceEnd();                }            }        }        traceBeginAndSlog("StartUserManagerService");        mSystemServiceManager.startService(UserManagerService.LifeCycle.class);        traceEnd();        // Initialize attribute cache used to cache resources from packages.        traceBeginAndSlog("InitAttributerCache");        AttributeCache.init(mSystemContext);        traceEnd();        // Set up the Application instance for the system process and get started.        traceBeginAndSlog("SetSystemProcess");        mActivityManagerService.setSystemProcess();        traceEnd();        // DisplayManagerService needs to setup android.display scheduling related policies        // since setSystemProcess() would have overridden policies due to setProcessGroup        mDisplayManagerService.setupSchedulerPolicies();        // Manages Overlay packages        traceBeginAndSlog("StartOverlayManagerService");        mSystemServiceManager.startService(new OverlayManagerService(mSystemContext, installer));        traceEnd();        // The sensor service needs access to package manager service, app ops        // service, and permissions service, therefore we start it after them.        // Start sensor service in a separate thread. Completion should be checked        // before using it.        mSensorServiceStart = SystemServerInitThreadPool.get().submit(() -> {            TimingsTraceLog traceLog = new TimingsTraceLog(                    SYSTEM_SERVER_TIMING_ASYNC_TAG, Trace.TRACE_TAG_SYSTEM_SERVER);            traceLog.traceBegin(START_SENSOR_SERVICE);            startSensorService();            traceLog.traceEnd();        }, START_SENSOR_SERVICE);    }

2.2.4 startCoreServices

感觉是为bootstrap的补充

   /**     * Starts some essential services that are not tangled up in the bootstrap process.     */    private void startCoreServices() {        // Records errors and logs, for example wtf()        traceBeginAndSlog("StartDropBoxManager");        mSystemServiceManager.startService(DropBoxManagerService.class);        traceEnd();        traceBeginAndSlog("StartBatteryService");        // Tracks the battery level.  Requires LightService.        mSystemServiceManager.startService(BatteryService.class);        traceEnd();        // Tracks application usage stats.        traceBeginAndSlog("StartUsageService");        mSystemServiceManager.startService(UsageStatsService.class);        mActivityManagerService.setUsageStatsManager(                LocalServices.getService(UsageStatsManagerInternal.class));        traceEnd();        // Tracks whether the updatable WebView is in a ready state and watches for update installs.        traceBeginAndSlog("StartWebViewUpdateService");        mWebViewUpdateService = mSystemServiceManager.startService(WebViewUpdateService.class);        traceEnd();    }

2.2.5 startOtherServices

1）比较熟的Service：BluetoothService、StartAccessibilityManagerService（无障碍）、StartStorageManagerService、StartDevicePolicyManager、StartNetworkScoreService、StartWifi、StartWifiScanning、StartWifiP2P、StartNotificationManager、StartLocationManagerService、StartUsbService、StartNightDisplay、StartNetworkTimeUpdateService)

2）观察到后半部分有调用startBootPhase和systemReady、systemRunning来进行Service的初始化，包括am和pm

3）另外有观察到systemUi被用startSystemUi(context, windowManagerF)调起来了

4） watchdog.init and Watchdog.getInstance().start();

    /**     * Starts a miscellaneous grab bag of stuff that has yet to be refactored     * and organized.     */    private void startOtherServices() {        final Context context = mSystemContext;        VibratorService vibrator = null;        IStorageManager storageManager = null;        NetworkManagementService networkManagement = null;        IpSecService ipSecService = null;        NetworkStatsService networkStats = null;        NetworkPolicyManagerService networkPolicy = null;        ConnectivityService connectivity = null;        NetworkScoreService networkScore = null;        NsdService serviceDiscovery= null;        WindowManagerService wm = null;        SerialService serial = null;        NetworkTimeUpdateService networkTimeUpdater = null;        CommonTimeManagementService commonTimeMgmtService = null;        InputManagerService inputManager = null;        TelephonyRegistry telephonyRegistry = null;        ConsumerIrService consumerIr = null;        MmsServiceBroker mmsService = null;        HardwarePropertiesManagerService hardwarePropertiesService = null;        boolean disableStorage = SystemProperties.getBoolean("config.disable_storage", false);        boolean disableBluetooth = SystemProperties.getBoolean("config.disable_bluetooth", false);        boolean disableLocation = SystemProperties.getBoolean("config.disable_location", false);        boolean disableSystemUI = SystemProperties.getBoolean("config.disable_systemui", false);        boolean disableNonCoreServices = SystemProperties.getBoolean("config.disable_noncore", false);        boolean disableNetwork = SystemProperties.getBoolean("config.disable_network", false);        boolean disableNetworkTime = SystemProperties.getBoolean("config.disable_networktime", false);        boolean disableRtt = SystemProperties.getBoolean("config.disable_rtt", false);        boolean disableMediaProjection = SystemProperties.getBoolean("config.disable_mediaproj",                false);        boolean disableSerial = SystemProperties.getBoolean("config.disable_serial", false);        boolean disableSearchManager = SystemProperties.getBoolean("config.disable_searchmanager",                false);        boolean disableTrustManager = SystemProperties.getBoolean("config.disable_trustmanager",                false);        boolean disableTextServices = SystemProperties.getBoolean("config.disable_textservices",                false);        boolean disableConsumerIr = SystemProperties.getBoolean("config.disable_consumerir", false);        boolean disableVrManager = SystemProperties.getBoolean("config.disable_vrmanager", false);        boolean disableCameraService = SystemProperties.getBoolean("config.disable_cameraservice",                false);        boolean enableLeftyService = SystemProperties.getBoolean("config.enable_lefty", false);        boolean isEmulator = SystemProperties.get("ro.kernel.qemu").equals("1");        // For debugging RescueParty        if (Build.IS_DEBUGGABLE && SystemProperties.getBoolean("debug.crash_system", false)) {            throw new RuntimeException();        }        try {            final String SECONDARY_ZYGOTE_PRELOAD = "SecondaryZygotePreload";            // We start the preload ~1s before the webview factory preparation, to            // ensure that it completes before the 32 bit relro process is forked            // from the zygote. In the event that it takes too long, the webview            // RELRO process will block, but it will do so without holding any locks.            mZygotePreload = SystemServerInitThreadPool.get().submit(() -> {                try {                    Slog.i(TAG, SECONDARY_ZYGOTE_PRELOAD);                    TimingsTraceLog traceLog = new TimingsTraceLog(                            SYSTEM_SERVER_TIMING_ASYNC_TAG, Trace.TRACE_TAG_SYSTEM_SERVER);                    traceLog.traceBegin(SECONDARY_ZYGOTE_PRELOAD);                    if (!Process.zygoteProcess.preloadDefault(Build.SUPPORTED_32_BIT_ABIS[0])) {                        Slog.e(TAG, "Unable to preload default resources");                    }                    traceLog.traceEnd();                } catch (Exception ex) {                    Slog.e(TAG, "Exception preloading default resources", ex);                }            }, SECONDARY_ZYGOTE_PRELOAD);            traceBeginAndSlog("StartKeyAttestationApplicationIdProviderService");            ServiceManager.addService("sec_key_att_app_id_provider",                    new KeyAttestationApplicationIdProviderService(context));            traceEnd();            traceBeginAndSlog("StartKeyChainSystemService");            mSystemServiceManager.startService(KeyChainSystemService.class);            traceEnd();            traceBeginAndSlog("StartSchedulingPolicyService");            ServiceManager.addService("scheduling_policy", new SchedulingPolicyService());            traceEnd();            traceBeginAndSlog("StartTelecomLoaderService");            mSystemServiceManager.startService(TelecomLoaderService.class);            traceEnd();            traceBeginAndSlog("StartTelephonyRegistry");            telephonyRegistry = new TelephonyRegistry(context);            ServiceManager.addService("telephony.registry", telephonyRegistry);            traceEnd();            traceBeginAndSlog("StartEntropyMixer");            mEntropyMixer = new EntropyMixer(context);            traceEnd();            mContentResolver = context.getContentResolver();            // The AccountManager must come before the ContentService            traceBeginAndSlog("StartAccountManagerService");            mSystemServiceManager.startService(ACCOUNT_SERVICE_CLASS);            traceEnd();            traceBeginAndSlog("StartContentService");            mSystemServiceManager.startService(CONTENT_SERVICE_CLASS);            traceEnd();            traceBeginAndSlog("InstallSystemProviders");            mActivityManagerService.installSystemProviders();            traceEnd();            traceBeginAndSlog("StartVibratorService");            vibrator = new VibratorService(context);            ServiceManager.addService("vibrator", vibrator);            traceEnd();            if (!disableConsumerIr) {                traceBeginAndSlog("StartConsumerIrService");                consumerIr = new ConsumerIrService(context);                ServiceManager.addService(Context.CONSUMER_IR_SERVICE, consumerIr);                traceEnd();            }            traceBeginAndSlog("StartAlarmManagerService");            mSystemServiceManager.startService(AlarmManagerService.class);            traceEnd();            traceBeginAndSlog("InitWatchdog");            final Watchdog watchdog = Watchdog.getInstance();            watchdog.init(context, mActivityManagerService);            traceEnd();            traceBeginAndSlog("StartInputManagerService");            inputManager = new InputManagerService(context);            traceEnd();            traceBeginAndSlog("StartWindowManagerService");            // WMS needs sensor service ready            ConcurrentUtils.waitForFutureNoInterrupt(mSensorServiceStart, START_SENSOR_SERVICE);            mSensorServiceStart = null;            wm = WindowManagerService.main(context, inputManager,                    mFactoryTestMode != FactoryTest.FACTORY_TEST_LOW_LEVEL,                    !mFirstBoot, mOnlyCore, new PhoneWindowManager());            ServiceManager.addService(Context.WINDOW_SERVICE, wm);            ServiceManager.addService(Context.INPUT_SERVICE, inputManager);            traceEnd();            // Start receiving calls from HIDL services. Start in in a separate thread            // because it need to connect to SensorManager. This have to start            // after START_SENSOR_SERVICE is done.            SystemServerInitThreadPool.get().submit(() -> {                TimingsTraceLog traceLog = new TimingsTraceLog(                        SYSTEM_SERVER_TIMING_ASYNC_TAG, Trace.TRACE_TAG_SYSTEM_SERVER);                traceLog.traceBegin(START_HIDL_SERVICES);                startHidlServices();                traceLog.traceEnd();            }, START_HIDL_SERVICES);            if (!disableVrManager) {                traceBeginAndSlog("StartVrManagerService");                mSystemServiceManager.startService(VrManagerService.class);                traceEnd();            }            traceBeginAndSlog("SetWindowManagerService");            mActivityManagerService.setWindowManager(wm);            traceEnd();            traceBeginAndSlog("StartInputManager");            inputManager.setWindowManagerCallbacks(wm.getInputMonitor());            inputManager.start();            traceEnd();            // TODO: Use service dependencies instead.            traceBeginAndSlog("DisplayManagerWindowManagerAndInputReady");            mDisplayManagerService.windowManagerAndInputReady();            traceEnd();            // Skip Bluetooth if we have an emulator kernel            // TODO: Use a more reliable check to see if this product should            // support Bluetooth - see bug 988521            if (isEmulator) {                Slog.i(TAG, "No Bluetooth Service (emulator)");            } else if (mFactoryTestMode == FactoryTest.FACTORY_TEST_LOW_LEVEL) {                Slog.i(TAG, "No Bluetooth Service (factory test)");            } else if (!context.getPackageManager().hasSystemFeature                       (PackageManager.FEATURE_BLUETOOTH)) {                Slog.i(TAG, "No Bluetooth Service (Bluetooth Hardware Not Present)");            } else if (disableBluetooth) {                Slog.i(TAG, "Bluetooth Service disabled by config");            } else {                traceBeginAndSlog("StartBluetoothService");                mSystemServiceManager.startService(BluetoothService.class);                traceEnd();            }            traceBeginAndSlog("IpConnectivityMetrics");            mSystemServiceManager.startService(IpConnectivityMetrics.class);            traceEnd();            traceBeginAndSlog("PinnerService");            mSystemServiceManager.startService(PinnerService.class);            traceEnd();        } catch (RuntimeException e) {            Slog.e("System", "******************************************");            Slog.e("System", "************ Failure starting core service", e);        }        StatusBarManagerService statusBar = null;        INotificationManager notification = null;        LocationManagerService location = null;        CountryDetectorService countryDetector = null;        ILockSettings lockSettings = null;        MediaRouterService mediaRouter = null;        // Bring up services needed for UI.        if (mFactoryTestMode != FactoryTest.FACTORY_TEST_LOW_LEVEL) {            traceBeginAndSlog("StartInputMethodManagerLifecycle");            mSystemServiceManager.startService(InputMethodManagerService.Lifecycle.class);            traceEnd();            traceBeginAndSlog("StartAccessibilityManagerService");            try {                ServiceManager.addService(Context.ACCESSIBILITY_SERVICE,                        new AccessibilityManagerService(context));            } catch (Throwable e) {                reportWtf("starting Accessibility Manager", e);            }            traceEnd();        }        traceBeginAndSlog("MakeDisplayReady");        try {            wm.displayReady();        } catch (Throwable e) {            reportWtf("making display ready", e);        }        traceEnd();        if (mFactoryTestMode != FactoryTest.FACTORY_TEST_LOW_LEVEL) {            if (!disableStorage &&                    !"0".equals(SystemProperties.get("system_init.startmountservice"))) {                traceBeginAndSlog("StartStorageManagerService");                try {                    /*                     * NotificationManagerService is dependant on StorageManagerService,                     * (for media / usb notifications) so we must start StorageManagerService first.                     */                    mSystemServiceManager.startService(STORAGE_MANAGER_SERVICE_CLASS);                    storageManager = IStorageManager.Stub.asInterface(                            ServiceManager.getService("mount"));                } catch (Throwable e) {                    reportWtf("starting StorageManagerService", e);                }                traceEnd();                traceBeginAndSlog("StartStorageStatsService");                try {                    mSystemServiceManager.startService(STORAGE_STATS_SERVICE_CLASS);                } catch (Throwable e) {                    reportWtf("starting StorageStatsService", e);                }                traceEnd();            }        }        // We start this here so that we update our configuration to set watch or television        // as appropriate.        traceBeginAndSlog("StartUiModeManager");        mSystemServiceManager.startService(UiModeManagerService.class);        traceEnd();        if (!mOnlyCore) {            traceBeginAndSlog("UpdatePackagesIfNeeded");            try {                mPackageManagerService.updatePackagesIfNeeded();            } catch (Throwable e) {                reportWtf("update packages", e);            }            traceEnd();        }        traceBeginAndSlog("PerformFstrimIfNeeded");        try {            mPackageManagerService.performFstrimIfNeeded();        } catch (Throwable e) {            reportWtf("performing fstrim", e);        }        traceEnd();        if (mFactoryTestMode != FactoryTest.FACTORY_TEST_LOW_LEVEL) {            if (!disableNonCoreServices) {                traceBeginAndSlog("StartLockSettingsService");                try {                    mSystemServiceManager.startService(LOCK_SETTINGS_SERVICE_CLASS);                    lockSettings = ILockSettings.Stub.asInterface(                            ServiceManager.getService("lock_settings"));                } catch (Throwable e) {                    reportWtf("starting LockSettingsService service", e);                }                traceEnd();                final boolean hasPdb = !SystemProperties.get(PERSISTENT_DATA_BLOCK_PROP).equals("");                if (hasPdb) {                    traceBeginAndSlog("StartPersistentDataBlock");                    mSystemServiceManager.startService(PersistentDataBlockService.class);                    traceEnd();                }                if (hasPdb || OemLockService.isHalPresent()) {                    // Implementation depends on pdb or the OemLock HAL                    traceBeginAndSlog("StartOemLockService");                    mSystemServiceManager.startService(OemLockService.class);                    traceEnd();                }                traceBeginAndSlog("StartDeviceIdleController");                mSystemServiceManager.startService(DeviceIdleController.class);                traceEnd();                // Always start the Device Policy Manager, so that the API is compatible with                // API8.                traceBeginAndSlog("StartDevicePolicyManager");                mSystemServiceManager.startService(DevicePolicyManagerService.Lifecycle.class);                traceEnd();            }            if (!disableSystemUI) {                traceBeginAndSlog("StartStatusBarManagerService");                try {                    statusBar = new StatusBarManagerService(context, wm);                    ServiceManager.addService(Context.STATUS_BAR_SERVICE, statusBar);                } catch (Throwable e) {                    reportWtf("starting StatusBarManagerService", e);                }                traceEnd();            }            if (!disableNonCoreServices) {                traceBeginAndSlog("StartClipboardService");                mSystemServiceManager.startService(ClipboardService.class);                traceEnd();            }            if (!disableNetwork) {                traceBeginAndSlog("StartNetworkManagementService");                try {                    networkManagement = NetworkManagementService.create(context);                    ServiceManager.addService(Context.NETWORKMANAGEMENT_SERVICE, networkManagement);                } catch (Throwable e) {                    reportWtf("starting NetworkManagement Service", e);                }                traceEnd();                traceBeginAndSlog("StartIpSecService");                try {                    ipSecService = IpSecService.create(context);                    ServiceManager.addService(Context.IPSEC_SERVICE, ipSecService);                } catch (Throwable e) {                    reportWtf("starting IpSec Service", e);                }                traceEnd();            }            if (!disableNonCoreServices && !disableTextServices) {                traceBeginAndSlog("StartTextServicesManager");                mSystemServiceManager.startService(TextServicesManagerService.Lifecycle.class);                traceEnd();            }            if (!disableNetwork) {                traceBeginAndSlog("StartNetworkScoreService");                try {                    networkScore = new NetworkScoreService(context);                    ServiceManager.addService(Context.NETWORK_SCORE_SERVICE, networkScore);                } catch (Throwable e) {                    reportWtf("starting Network Score Service", e);                }                traceEnd();                traceBeginAndSlog("StartNetworkStatsService");                try {                    networkStats = NetworkStatsService.create(context, networkManagement);                    ServiceManager.addService(Context.NETWORK_STATS_SERVICE, networkStats);                } catch (Throwable e) {                    reportWtf("starting NetworkStats Service", e);                }                traceEnd();                traceBeginAndSlog("StartNetworkPolicyManagerService");                try {                    networkPolicy = new NetworkPolicyManagerService(context,                            mActivityManagerService, networkStats, networkManagement);                    ServiceManager.addService(Context.NETWORK_POLICY_SERVICE, networkPolicy);                } catch (Throwable e) {                    reportWtf("starting NetworkPolicy Service", e);                }                traceEnd();                // Wifi Service must be started first for wifi-related services.                traceBeginAndSlog("StartWifi");                mSystemServiceManager.startService(WIFI_SERVICE_CLASS);                traceEnd();                traceBeginAndSlog("StartWifiScanning");                mSystemServiceManager.startService(                        "com.android.server.wifi.scanner.WifiScanningService");                traceEnd();                if (!disableRtt) {                    traceBeginAndSlog("StartWifiRtt");                    mSystemServiceManager.startService("com.android.server.wifi.RttService");                    traceEnd();                }                if (context.getPackageManager().hasSystemFeature(                        PackageManager.FEATURE_WIFI_AWARE)) {                    traceBeginAndSlog("StartWifiAware");                    mSystemServiceManager.startService(WIFI_AWARE_SERVICE_CLASS);                    traceEnd();                } else {                    Slog.i(TAG, "No Wi-Fi Aware Service (Aware support Not Present)");                }                if (context.getPackageManager().hasSystemFeature(                        PackageManager.FEATURE_WIFI_DIRECT)) {                    traceBeginAndSlog("StartWifiP2P");                    mSystemServiceManager.startService(WIFI_P2P_SERVICE_CLASS);                    traceEnd();                }                if (context.getPackageManager().hasSystemFeature(                        PackageManager.FEATURE_LOWPAN)) {                    traceBeginAndSlog("StartLowpan");                    mSystemServiceManager.startService(LOWPAN_SERVICE_CLASS);                    traceEnd();                }                if (mPackageManager.hasSystemFeature(PackageManager.FEATURE_ETHERNET) ||                    mPackageManager.hasSystemFeature(PackageManager.FEATURE_USB_HOST)) {                    traceBeginAndSlog("StartEthernet");                    mSystemServiceManager.startService(ETHERNET_SERVICE_CLASS);                    traceEnd();                }                traceBeginAndSlog("StartConnectivityService");                try {                    connectivity = new ConnectivityService(                            context, networkManagement, networkStats, networkPolicy);                    ServiceManager.addService(Context.CONNECTIVITY_SERVICE, connectivity);                    networkStats.bindConnectivityManager(connectivity);                    networkPolicy.bindConnectivityManager(connectivity);                } catch (Throwable e) {                    reportWtf("starting Connectivity Service", e);                }                traceEnd();                traceBeginAndSlog("StartNsdService");                try {                    serviceDiscovery = NsdService.create(context);                    ServiceManager.addService(                            Context.NSD_SERVICE, serviceDiscovery);                } catch (Throwable e) {                    reportWtf("starting Service Discovery Service", e);                }                traceEnd();            }            if (!disableNonCoreServices) {                traceBeginAndSlog("StartUpdateLockService");                try {                    ServiceManager.addService(Context.UPDATE_LOCK_SERVICE,                            new UpdateLockService(context));                } catch (Throwable e) {                    reportWtf("starting UpdateLockService", e);                }                traceEnd();            }            /*             * StorageManagerService has a few dependencies: Notification Manager and             * AppWidget Provider. Make sure StorageManagerService is completely started             * first before continuing.             */            if (storageManager != null && !mOnlyCore) {                traceBeginAndSlog("WaitForAsecScan");                try {                    storageManager.waitForAsecScan();                } catch (RemoteException ignored) {                }                traceEnd();            }            traceBeginAndSlog("StartNotificationManager");            mSystemServiceManager.startService(NotificationManagerService.class);            SystemNotificationChannels.createAll(context);            notification = INotificationManager.Stub.asInterface(                    ServiceManager.getService(Context.NOTIFICATION_SERVICE));            networkPolicy.bindNotificationManager(notification);            traceEnd();            traceBeginAndSlog("StartDeviceMonitor");            mSystemServiceManager.startService(DeviceStorageMonitorService.class);            traceEnd();            if (!disableLocation) {                traceBeginAndSlog("StartLocationManagerService");                try {                    location = new LocationManagerService(context);                    ServiceManager.addService(Context.LOCATION_SERVICE, location);                } catch (Throwable e) {                    reportWtf("starting Location Manager", e);                }                traceEnd();                traceBeginAndSlog("StartCountryDetectorService");                try {                    countryDetector = new CountryDetectorService(context);                    ServiceManager.addService(Context.COUNTRY_DETECTOR, countryDetector);                } catch (Throwable e) {                    reportWtf("starting Country Detector", e);                }                traceEnd();            }            if (!disableNonCoreServices && !disableSearchManager) {                traceBeginAndSlog("StartSearchManagerService");                try {                    mSystemServiceManager.startService(SEARCH_MANAGER_SERVICE_CLASS);                } catch (Throwable e) {                    reportWtf("starting Search Service", e);                }                traceEnd();            }            if (!disableNonCoreServices && context.getResources().getBoolean(                        R.bool.config_enableWallpaperService)) {                traceBeginAndSlog("StartWallpaperManagerService");                mSystemServiceManager.startService(WALLPAPER_SERVICE_CLASS);                traceEnd();            }            traceBeginAndSlog("StartAudioService");            mSystemServiceManager.startService(AudioService.Lifecycle.class);            traceEnd();            if (mPackageManager.hasSystemFeature(PackageManager.FEATURE_BROADCAST_RADIO)) {                traceBeginAndSlog("StartBroadcastRadioService");                mSystemServiceManager.startService(BroadcastRadioService.class);                traceEnd();            }            if (!disableNonCoreServices) {                traceBeginAndSlog("StartDockObserver");                mSystemServiceManager.startService(DockObserver.class);                traceEnd();                if (context.getPackageManager().hasSystemFeature(PackageManager.FEATURE_WATCH)) {                    traceBeginAndSlog("StartThermalObserver");                    mSystemServiceManager.startService(THERMAL_OBSERVER_CLASS);                    traceEnd();                }            }            traceBeginAndSlog("StartWiredAccessoryManager");            try {                // Listen for wired headset changes                inputManager.setWiredAccessoryCallbacks(                        new WiredAccessoryManager(context, inputManager));            } catch (Throwable e) {                reportWtf("starting WiredAccessoryManager", e);            }            traceEnd();            if (!disableNonCoreServices) {                if (mPackageManager.hasSystemFeature(PackageManager.FEATURE_MIDI)) {                    // Start MIDI Manager service                    traceBeginAndSlog("StartMidiManager");                    mSystemServiceManager.startService(MIDI_SERVICE_CLASS);                    traceEnd();                }                if (mPackageManager.hasSystemFeature(PackageManager.FEATURE_USB_HOST)                        || mPackageManager.hasSystemFeature(                                PackageManager.FEATURE_USB_ACCESSORY)) {                    // Manage USB host and device support                    traceBeginAndSlog("StartUsbService");                    mSystemServiceManager.startService(USB_SERVICE_CLASS);                    traceEnd();                }                if (!disableSerial) {                    traceBeginAndSlog("StartSerialService");                    try {                        // Serial port support                        serial = new SerialService(context);                        ServiceManager.addService(Context.SERIAL_SERVICE, serial);                    } catch (Throwable e) {                        Slog.e(TAG, "Failure starting SerialService", e);                    }                    traceEnd();                }                traceBeginAndSlog("StartHardwarePropertiesManagerService");                try {                    hardwarePropertiesService = new HardwarePropertiesManagerService(context);                    ServiceManager.addService(Context.HARDWARE_PROPERTIES_SERVICE,                            hardwarePropertiesService);                } catch (Throwable e) {                    Slog.e(TAG, "Failure starting HardwarePropertiesManagerService", e);                }                traceEnd();            }            traceBeginAndSlog("StartTwilightService");            mSystemServiceManager.startService(TwilightService.class);            traceEnd();            if (NightDisplayController.isAvailable(context)) {                traceBeginAndSlog("StartNightDisplay");                mSystemServiceManager.startService(NightDisplayService.class);                traceEnd();            }            traceBeginAndSlog("StartJobScheduler");            mSystemServiceManager.startService(JobSchedulerService.class);            traceEnd();            traceBeginAndSlog("StartSoundTrigger");            mSystemServiceManager.startService(SoundTriggerService.class);            traceEnd();            if (!disableNonCoreServices) {                if (!disableTrustManager) {                    traceBeginAndSlog("StartTrustManager");                    mSystemServiceManager.startService(TrustManagerService.class);                    traceEnd();                }                if (mPackageManager.hasSystemFeature(PackageManager.FEATURE_BACKUP)) {                    traceBeginAndSlog("StartBackupManager");                    mSystemServiceManager.startService(BACKUP_MANAGER_SERVICE_CLASS);                    traceEnd();                }                if (mPackageManager.hasSystemFeature(PackageManager.FEATURE_APP_WIDGETS)                    || context.getResources().getBoolean(R.bool.config_enableAppWidgetService)) {                    traceBeginAndSlog("StartAppWidgerService");                    mSystemServiceManager.startService(APPWIDGET_SERVICE_CLASS);                    traceEnd();                }                // We need to always start this service, regardless of whether the                // FEATURE_VOICE_RECOGNIZERS feature is set, because it needs to take care                // of initializing various settings.  It will internally modify its behavior                // based on that feature.                traceBeginAndSlog("StartVoiceRecognitionManager");                mSystemServiceManager.startService(VOICE_RECOGNITION_MANAGER_SERVICE_CLASS);                traceEnd();                if (GestureLauncherService.isGestureLauncherEnabled(context.getResources())) {                    traceBeginAndSlog("StartGestureLauncher");                    mSystemServiceManager.startService(GestureLauncherService.class);                    traceEnd();                }                traceBeginAndSlog("StartSensorNotification");                mSystemServiceManager.startService(SensorNotificationService.class);                traceEnd();                traceBeginAndSlog("StartContextHubSystemService");                mSystemServiceManager.startService(ContextHubSystemService.class);                traceEnd();            }            traceBeginAndSlog("StartDiskStatsService");            try {                ServiceManager.addService("diskstats", new DiskStatsService(context));            } catch (Throwable e) {                reportWtf("starting DiskStats Service", e);            }            traceEnd();            // timezone.RulesManagerService will prevent a device starting up if the chain of trust            // required for safe time zone updates might be broken. RuleManagerService cannot do            // this check when mOnlyCore == true, so we don't enable the service in this case.            // This service requires that JobSchedulerService is already started when it starts.            final boolean startRulesManagerService =                    !mOnlyCore && context.getResources().getBoolean(                            R.bool.config_enableUpdateableTimeZoneRules);            if (startRulesManagerService) {                traceBeginAndSlog("StartTimeZoneRulesManagerService");                mSystemServiceManager.startService(TIME_ZONE_RULES_MANAGER_SERVICE_CLASS);                traceEnd();            }            if (!disableNetwork && !disableNetworkTime) {                traceBeginAndSlog("StartNetworkTimeUpdateService");                try {                    networkTimeUpdater = new NetworkTimeUpdateService(context);                    ServiceManager.addService("network_time_update_service", networkTimeUpdater);                } catch (Throwable e) {                    reportWtf("starting NetworkTimeUpdate service", e);                }                traceEnd();            }            traceBeginAndSlog("StartCommonTimeManagementService");            try {                commonTimeMgmtService = new CommonTimeManagementService(context);                ServiceManager.addService("commontime_management", commonTimeMgmtService);            } catch (Throwable e) {                reportWtf("starting CommonTimeManagementService service", e);            }            traceEnd();            if (!disableNetwork) {                traceBeginAndSlog("CertBlacklister");                try {                    CertBlacklister blacklister = new CertBlacklister(context);                } catch (Throwable e) {                    reportWtf("starting CertBlacklister", e);                }                traceEnd();            }            if (!disableNetwork && !disableNonCoreServices && EmergencyAffordanceManager.ENABLED) {                // EmergencyMode service                traceBeginAndSlog("StartEmergencyAffordanceService");                mSystemServiceManager.startService(EmergencyAffordanceService.class);                traceEnd();            }            if (!disableNonCoreServices) {                // Dreams (interactive idle-time views, a/k/a screen savers, and doze mode)                traceBeginAndSlog("StartDreamManager");                mSystemServiceManager.startService(DreamManagerService.class);                traceEnd();            }            if (!disableNonCoreServices) {                traceBeginAndSlog("AddGraphicsStatsService");                ServiceManager.addService(GraphicsStatsService.GRAPHICS_STATS_SERVICE,                        new GraphicsStatsService(context));                traceEnd();            }            if (!disableNonCoreServices && CoverageService.ENABLED) {                traceBeginAndSlog("AddCoverageService");                ServiceManager.addService(CoverageService.COVERAGE_SERVICE, new CoverageService());                traceEnd();            }            if (mPackageManager.hasSystemFeature(PackageManager.FEATURE_PRINTING)) {                traceBeginAndSlog("StartPrintManager");                mSystemServiceManager.startService(PRINT_MANAGER_SERVICE_CLASS);                traceEnd();            }            if (mPackageManager.hasSystemFeature(PackageManager.FEATURE_COMPANION_DEVICE_SETUP)) {                traceBeginAndSlog("StartCompanionDeviceManager");                mSystemServiceManager.startService(COMPANION_DEVICE_MANAGER_SERVICE_CLASS);                traceEnd();            }            traceBeginAndSlog("StartRestrictionManager");            mSystemServiceManager.startService(RestrictionsManagerService.class);            traceEnd();            traceBeginAndSlog("StartMediaSessionService");            mSystemServiceManager.startService(MediaSessionService.class);            traceEnd();            if (mPackageManager.hasSystemFeature(PackageManager.FEATURE_HDMI_CEC)) {                traceBeginAndSlog("StartHdmiControlService");                mSystemServiceManager.startService(HdmiControlService.class);                traceEnd();            }            if (mPackageManager.hasSystemFeature(PackageManager.FEATURE_LIVE_TV)                    || mPackageManager.hasSystemFeature(PackageManager.FEATURE_LEANBACK)) {                traceBeginAndSlog("StartTvInputManager");                mSystemServiceManager.startService(TvInputManagerService.class);                traceEnd();            }            if (mPackageManager.hasSystemFeature(PackageManager.FEATURE_PICTURE_IN_PICTURE)) {                traceBeginAndSlog("StartMediaResourceMonitor");                mSystemServiceManager.startService(MediaResourceMonitorService.class);                traceEnd();            }            if (mPackageManager.hasSystemFeature(PackageManager.FEATURE_LEANBACK)) {                traceBeginAndSlog("StartTvRemoteService");                mSystemServiceManager.startService(TvRemoteService.class);                traceEnd();            }            if (!disableNonCoreServices) {                traceBeginAndSlog("StartMediaRouterService");                try {                    mediaRouter = new MediaRouterService(context);                    ServiceManager.addService(Context.MEDIA_ROUTER_SERVICE, mediaRouter);                } catch (Throwable e) {                    reportWtf("starting MediaRouterService", e);                }                traceEnd();                if (mPackageManager.hasSystemFeature(PackageManager.FEATURE_FINGERPRINT)) {                    traceBeginAndSlog("StartFingerprintSensor");                    mSystemServiceManager.startService(FingerprintService.class);                    traceEnd();                }                traceBeginAndSlog("StartBackgroundDexOptService");                try {                    BackgroundDexOptService.schedule(context);                } catch (Throwable e) {                    reportWtf("starting StartBackgroundDexOptService", e);                }                traceEnd();                traceBeginAndSlog("StartPruneInstantAppsJobService");                try {                    PruneInstantAppsJobService.schedule(context);                } catch (Throwable e) {                    reportWtf("StartPruneInstantAppsJobService", e);                }                traceEnd();            }            // LauncherAppsService uses ShortcutService.            traceBeginAndSlog("StartShortcutServiceLifecycle");            mSystemServiceManager.startService(ShortcutService.Lifecycle.class);            traceEnd();            traceBeginAndSlog("StartLauncherAppsService");            mSystemServiceManager.startService(LauncherAppsService.class);            traceEnd();        }        if (!disableNonCoreServices && !disableMediaProjection) {            traceBeginAndSlog("StartMediaProjectionManager");            mSystemServiceManager.startService(MediaProjectionManagerService.class);            traceEnd();        }        if (context.getPackageManager().hasSystemFeature(PackageManager.FEATURE_WATCH)) {            traceBeginAndSlog("StartWearConnectivityService");            mSystemServiceManager.startService(WEAR_CONNECTIVITY_SERVICE_CLASS);            traceEnd();            if (!disableNonCoreServices) {                traceBeginAndSlog("StartWearTimeService");                mSystemServiceManager.startService(WEAR_DISPLAY_SERVICE_CLASS);                mSystemServiceManager.startService(WEAR_TIME_SERVICE_CLASS);                traceEnd();                if (enableLeftyService) {                    traceBeginAndSlog("StartWearLeftyService");                    mSystemServiceManager.startService(WEAR_LEFTY_SERVICE_CLASS);                    traceEnd();                }            }        }        if (!disableCameraService) {            traceBeginAndSlog("StartCameraServiceProxy");            mSystemServiceManager.startService(CameraServiceProxy.class);            traceEnd();        }        // Before things start rolling, be sure we have decided whether        // we are in safe mode.        final boolean safeMode = wm.detectSafeMode();        if (safeMode) {            traceBeginAndSlog("EnterSafeModeAndDisableJitCompilation");            mActivityManagerService.enterSafeMode();            // Disable the JIT for the system_server process            VMRuntime.getRuntime().disableJitCompilation();            traceEnd();        } else {            // Enable the JIT for the system_server process            traceBeginAndSlog("StartJitCompilation");            VMRuntime.getRuntime().startJitCompilation();            traceEnd();        }        // MMS service broker        traceBeginAndSlog("StartMmsService");        mmsService = mSystemServiceManager.startService(MmsServiceBroker.class);        traceEnd();        if (mPackageManager.hasSystemFeature(PackageManager.FEATURE_AUTOFILL)) {            traceBeginAndSlog("StartAutoFillService");            mSystemServiceManager.startService(AUTO_FILL_MANAGER_SERVICE_CLASS);            traceEnd();        }        // It is now time to start up the app processes...        traceBeginAndSlog("MakeVibratorServiceReady");        try {            vibrator.systemReady();        } catch (Throwable e) {            reportWtf("making Vibrator Service ready", e);        }        traceEnd();        traceBeginAndSlog("MakeLockSettingsServiceReady");        if (lockSettings != null) {            try {                lockSettings.systemReady();            } catch (Throwable e) {                reportWtf("making Lock Settings Service ready", e);            }        }        traceEnd();        // Needed by DevicePolicyManager for initialization        traceBeginAndSlog("StartBootPhaseLockSettingsReady");        mSystemServiceManager.startBootPhase(SystemService.PHASE_LOCK_SETTINGS_READY);        traceEnd();        traceBeginAndSlog("StartBootPhaseSystemServicesReady");        mSystemServiceManager.startBootPhase(SystemService.PHASE_SYSTEM_SERVICES_READY);        traceEnd();        traceBeginAndSlog("MakeWindowManagerServiceReady");        try {            wm.systemReady();        } catch (Throwable e) {            reportWtf("making Window Manager Service ready", e);        }        traceEnd();        if (safeMode) {            mActivityManagerService.showSafeModeOverlay();        }        // Update the configuration for this context by hand, because we're going        // to start using it before the config change done in wm.systemReady() will        // propagate to it.        final Configuration config = wm.computeNewConfiguration(DEFAULT_DISPLAY);        DisplayMetrics metrics = new DisplayMetrics();        WindowManager w = (WindowManager)context.getSystemService(Context.WINDOW_SERVICE);        w.getDefaultDisplay().getMetrics(metrics);        context.getResources().updateConfiguration(config, metrics);        // The system context's theme may be configuration-dependent.        final Theme systemTheme = context.getTheme();        if (systemTheme.getChangingConfigurations() != 0) {            systemTheme.rebase();        }        traceBeginAndSlog("MakePowerManagerServiceReady");        try {            // TODO: use boot phase            mPowerManagerService.systemReady(mActivityManagerService.getAppOpsService());        } catch (Throwable e) {            reportWtf("making Power Manager Service ready", e);        }        traceEnd();        traceBeginAndSlog("MakePackageManagerServiceReady");        try {            mPackageManagerService.systemReady();        } catch (Throwable e) {            reportWtf("making Package Manager Service ready", e);        }        traceEnd();        traceBeginAndSlog("MakeDisplayManagerServiceReady");        try {            // TODO: use boot phase and communicate these flags some other way            mDisplayManagerService.systemReady(safeMode, mOnlyCore);        } catch (Throwable e) {            reportWtf("making Display Manager Service ready", e);        }        traceEnd();        mSystemServiceManager.setSafeMode(safeMode);        // These are needed to propagate to the runnable below.        final NetworkManagementService networkManagementF = networkManagement;        final NetworkStatsService networkStatsF = networkStats;        final NetworkPolicyManagerService networkPolicyF = networkPolicy;        final ConnectivityService connectivityF = connectivity;        final NetworkScoreService networkScoreF = networkScore;        final LocationManagerService locationF = location;        final CountryDetectorService countryDetectorF = countryDetector;        final NetworkTimeUpdateService networkTimeUpdaterF = networkTimeUpdater;        final CommonTimeManagementService commonTimeMgmtServiceF = commonTimeMgmtService;        final InputManagerService inputManagerF = inputManager;        final TelephonyRegistry telephonyRegistryF = telephonyRegistry;        final MediaRouterService mediaRouterF = mediaRouter;        final MmsServiceBroker mmsServiceF = mmsService;        final IpSecService ipSecServiceF = ipSecService;        final WindowManagerService windowManagerF = wm;        // We now tell the activity manager it is okay to run third party        // code.  It will call back into us once it has gotten to the state        // where third party code can really run (but before it has actually        // started launching the initial applications), for us to complete our        // initialization.        mActivityManagerService.systemReady(() -> {            Slog.i(TAG, "Making services ready");            traceBeginAndSlog("StartActivityManagerReadyPhase");            mSystemServiceManager.startBootPhase(                    SystemService.PHASE_ACTIVITY_MANAGER_READY);            traceEnd();            traceBeginAndSlog("StartObservingNativeCrashes");            try {                mActivityManagerService.startObservingNativeCrashes();            } catch (Throwable e) {                reportWtf("observing native crashes", e);            }            traceEnd();            // No dependency on Webview preparation in system server. But this should            // be completed before allowring 3rd party            final String WEBVIEW_PREPARATION = "WebViewFactoryPreparation";            Future<?> webviewPrep = null;            if (!mOnlyCore) {                webviewPrep = SystemServerInitThreadPool.get().submit(() -> {                    Slog.i(TAG, WEBVIEW_PREPARATION);                    TimingsTraceLog traceLog = new TimingsTraceLog(                            SYSTEM_SERVER_TIMING_ASYNC_TAG, Trace.TRACE_TAG_SYSTEM_SERVER);                    traceLog.traceBegin(WEBVIEW_PREPARATION);                    ConcurrentUtils.waitForFutureNoInterrupt(mZygotePreload, "Zygote preload");                    mZygotePreload = null;                    mWebViewUpdateService.prepareWebViewInSystemServer();                    traceLog.traceEnd();                }, WEBVIEW_PREPARATION);            }            if (mPackageManager.hasSystemFeature(PackageManager.FEATURE_AUTOMOTIVE)) {                traceBeginAndSlog("StartCarServiceHelperService");                mSystemServiceManager.startService(CarServiceHelperService.class);                traceEnd();            }            traceBeginAndSlog("StartSystemUI");            try {                startSystemUi(context, windowManagerF);            } catch (Throwable e) {                reportWtf("starting System UI", e);            }            traceEnd();            traceBeginAndSlog("MakeNetworkScoreReady");            try {                if (networkScoreF != null) networkScoreF.systemReady();            } catch (Throwable e) {                reportWtf("making Network Score Service ready", e);            }            traceEnd();            traceBeginAndSlog("MakeNetworkManagementServiceReady");            try {                if (networkManagementF != null) networkManagementF.systemReady();            } catch (Throwable e) {                reportWtf("making Network Managment Service ready", e);            }            CountDownLatch networkPolicyInitReadySignal = null;            if (networkPolicyF != null) {                networkPolicyInitReadySignal = networkPolicyF                        .networkScoreAndNetworkManagementServiceReady();            }            traceEnd();            traceBeginAndSlog("MakeIpSecServiceReady");            try {                if (ipSecServiceF != null) ipSecServiceF.systemReady();            } catch (Throwable e) {                reportWtf("making IpSec Service ready", e);            }            traceEnd();            traceBeginAndSlog("MakeNetworkStatsServiceReady");            try {                if (networkStatsF != null) networkStatsF.systemReady();            } catch (Throwable e) {                reportWtf("making Network Stats Service ready", e);            }            traceEnd();            traceBeginAndSlog("MakeConnectivityServiceReady");            try {                if (connectivityF != null) connectivityF.systemReady();            } catch (Throwable e) {                reportWtf("making Connectivity Service ready", e);            }            traceEnd();            traceBeginAndSlog("MakeNetworkPolicyServiceReady");            try {                if (networkPolicyF != null) {                    networkPolicyF.systemReady(networkPolicyInitReadySignal);                }            } catch (Throwable e) {                reportWtf("making Network Policy Service ready", e);            }            traceEnd();            traceBeginAndSlog("StartWatchdog");            Watchdog.getInstance().start();            traceEnd();            // Wait for all packages to be prepared            mPackageManagerService.waitForAppDataPrepared();            // It is now okay to let the various system services start their            // third party code...            traceBeginAndSlog("PhaseThirdPartyAppsCanStart");            // confirm webview completion before starting 3rd party            if (webviewPrep != null) {                ConcurrentUtils.waitForFutureNoInterrupt(webviewPrep, WEBVIEW_PREPARATION);            }            mSystemServiceManager.startBootPhase(                    SystemService.PHASE_THIRD_PARTY_APPS_CAN_START);            traceEnd();            traceBeginAndSlog("MakeLocationServiceReady");            try {                if (locationF != null) locationF.systemRunning();            } catch (Throwable e) {                reportWtf("Notifying Location Service running", e);            }            traceEnd();            traceBeginAndSlog("MakeCountryDetectionServiceReady");            try {                if (countryDetectorF != null) countryDetectorF.systemRunning();            } catch (Throwable e) {                reportWtf("Notifying CountryDetectorService running", e);            }            traceEnd();            traceBeginAndSlog("MakeNetworkTimeUpdateReady");            try {                if (networkTimeUpdaterF != null) networkTimeUpdaterF.systemRunning();            } catch (Throwable e) {                reportWtf("Notifying NetworkTimeService running", e);            }            traceEnd();            traceBeginAndSlog("MakeCommonTimeManagementServiceReady");            try {                if (commonTimeMgmtServiceF != null) {                    commonTimeMgmtServiceF.systemRunning();                }            } catch (Throwable e) {                reportWtf("Notifying CommonTimeManagementService running", e);            }            traceEnd();            traceBeginAndSlog("MakeInputManagerServiceReady");            try {                // TODO(BT) Pass parameter to input manager                if (inputManagerF != null) inputManagerF.systemRunning();            } catch (Throwable e) {                reportWtf("Notifying InputManagerService running", e);            }            traceEnd();            traceBeginAndSlog("MakeTelephonyRegistryReady");            try {                if (telephonyRegistryF != null) telephonyRegistryF.systemRunning();            } catch (Throwable e) {                reportWtf("Notifying TelephonyRegistry running", e);            }            traceEnd();            traceBeginAndSlog("MakeMediaRouterServiceReady");            try {                if (mediaRouterF != null) mediaRouterF.systemRunning();            } catch (Throwable e) {                reportWtf("Notifying MediaRouterService running", e);            }            traceEnd();            traceBeginAndSlog("MakeMmsServiceReady");            try {                if (mmsServiceF != null) mmsServiceF.systemRunning();            } catch (Throwable e) {                reportWtf("Notifying MmsService running", e);            }            traceEnd();            traceBeginAndSlog("MakeNetworkScoreServiceReady");            try {                if (networkScoreF != null) networkScoreF.systemRunning();            } catch (Throwable e) {                reportWtf("Notifying NetworkScoreService running", e);            }            traceEnd();            traceBeginAndSlog("IncidentDaemonReady");            try {                // TODO: Switch from checkService to getService once it's always                // in the build and should reliably be there.                final IIncidentManager incident = IIncidentManager.Stub.asInterface(                        ServiceManager.checkService("incident"));                if (incident != null) incident.systemRunning();            } catch (Throwable e) {                reportWtf("Notifying incident daemon running", e);            }            traceEnd();        }, BOOT_TIMINGS_TRACE_LOG);

PS:

system_server进程中的服务启动方式有两种，分别是SystemServiceManager的startService()和ServiceManager的addService

1）startService
通过SystemServiceManager的startService(Class serviceClass)用于启动继承于SystemService的服务。主要功能：
a、创建serviceClass类对象，将新建对象注册到SystemServiceManager的成员变量mServices;
b、调用新建对象的onStart()方法，即调用serviceClass.onStart()；
c、当系统启动到一个新的阶段Phase时，SystemServiceManager的startBootPhase()会循环遍历所有向SystemServiceManager注册过服务的onBootPhase()方法，即调用serviceClass.onBootPhase()。
例如：mSystemServiceManager.startService(PowerManagerService.class);

2）addService
通过ServiceManager的addService(String name, IBinder service)用于初始化继承于IBinder的服务。主要功能:
a、将该服务向Native层的serviceManager注册服务。

例如：ServiceManager.addService(Context.WINDOW_SERVICE, wm);

3）system_server进程，从源码角度划分为引导服务、核心服务、其他服务3类。

引导服务(7个)：ActivityManagerService、PowerManagerService、LightsService、DisplayManagerService、PackageManagerService、UserManagerService、SensorService；
核心服务(3个)：BatteryService、UsageStatsService、WebViewUpdateService；

其他服务(70个+)：AlarmManagerService、VibratorService等。

3.总结

SystemServer可以看成启动所有服务的发起者，我们熟知的有am/pm/蓝牙/WiFi相关服务，并随着Android启动过程的推进完成一些服务的初始化工作。

（四十一） Android(安卓)O SystemServer初探