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本篇文章主要介绍 Android 开发中的部分知识点，通过阅读本篇文章，您将收获以下内容:
1.ShutdownThread 概述
2.shutdown 关机方法
3.shutdownInner 方法实现
4.CloseDialogReceiver 注册关机对话框广播
5.new sConfirmDialog 显示关机对话框
6.beginShutdownSequence开始关机流程
7.showShutdownDialog 显示关机进度对话框
8.判断是否显示SystemUIReboot
9.启动 关机线程 ，执行 Run 方法
10.shutdownRadios 关闭Radio 实现
11.rebootOrShutdown 初始化并决定关机还是重启
12.关机log 分析
1.ShutdownThread 概述
关机线程实现类
Android关机线程实现类frameworks/base/services/core/java/com/android/server/power/ShutdownThread.java
ShutdownThread 大致流程
ShutdownThread 部分静态变量如下：
public final class ShutdownThread extends Thread {
// constants
private static final String TAG = "ShutdownThread";
private static final int ACTION_DONE_POLL_WAIT_MS = 500;
private static final int RADIOS_STATE_POLL_SLEEP_MS = 100;
// maximum time we wait for the shutdown broadcast before going on.
private static final int MAX_BROADCAST_TIME = 10*1000;
private static final int MAX_SHUTDOWN_WAIT_TIME = 20*1000;
private static final int MAX_RADIO_WAIT_TIME = 12*1000;
private static final int MAX_UNCRYPT_WAIT_TIME = 15*60*1000;
// constants for progress bar. the values are roughly estimated based on timeout.
private static final int BROADCAST_STOP_PERCENT = 2;
private static final int ACTIVITY_MANAGER_STOP_PERCENT = 4;
private static final int PACKAGE_MANAGER_STOP_PERCENT = 6;
private static final int RADIO_STOP_PERCENT = 18;
private static final int MOUNT_SERVICE_STOP_PERCENT = 20;
// Time we should wait for vendor subsystem shutdown
// Sleep times(ms) between checks of the vendor subsystem state
private static final int VENDOR_SUBSYS_STATE_CHECK_INTERVAL_MS = 100;
// Max time we wait for vendor subsystems to shut down before resuming
// with full system shutdown
private static final int VENDOR_SUBSYS_MAX_WAIT_MS = 10000;
// length of vibration before shutting down
private static final int SHUTDOWN_VIBRATE_MS = 500;
... ...
}ShutdownThread 无参构造方法
private ShutdownThread() {
}2. shutdown 关机方法
长按 ·Power· 键调用 shutdown方法，通过调用内部shutdownInner方法，实现 弹出 关机 、重启对话框，供用户选择关机 或者重启。
/**
* Request a clean shutdown, waiting for subsystems to clean up their
* state etc. Must be called from a Looper thread in which its UI
* is shown.
*
* @param context Context used to display the shutdown progress dialog. This must be a context
* suitable for displaying UI (aka Themable).
* @param reason code to pass to android_reboot() (e.g. "userrequested"), or null.
* @param confirm true if user confirmation is needed before shutting down.
*/
public static void shutdown(final Context context, String reason, boolean confirm) {
mReboot = false;
mRebootSafeMode = false;
mReason = reason;
shutdownInner(context, confirm); // 详见分析3
}3.shutdownInner 方法实现
shutdownInner 主要作用是
1.获取用户关机 Behavior。
2.注册关机广播，详见4.
3.创建关机Dialog。
4.执行一系列关机流程。
private static void shutdownInner(final Context context, boolean confirm) {
// ShutdownThread is called from many places, so best to verify here that the context passed
// in is themed.
context.assertRuntimeOverlayThemable();
// ensure that only one thread is trying to power down.
// any additional calls are just returned
synchronized (sIsStartedGuard) {
if (sIsStarted) {
Log.d(TAG, "Request to shutdown already running, returning.");
return;
}
}
// 获取用户长按Power键的处理行为
final int longPressBehavior = context.getResources().getInteger(
com.android.internal.R.integer.config_longPressOnPowerBehavior);
final int resourceId = mRebootSafeMode
? com.android.internal.R.string.reboot_safemode_confirm
: (longPressBehavior == 2
? com.android.internal.R.string.shutdown_confirm_question
: com.android.internal.R.string.shutdown_confirm);
Log.d(TAG, "Notifying thread to start shutdown longPressBehavior=" + longPressBehavior);
if (confirm) {
//注册关机对话框广播 详细实现见 4
final CloseDialogReceiver closer = new CloseDialogReceiver(context);
if (sConfirmDialog != null) {
sConfirmDialog.dismiss();
}
// 创建关机Dialg 详见 实现5
sConfirmDialog = new AlertDialog.Builder(context)
.setTitle(mRebootSafeMode
? com.android.internal.R.string.reboot_safemode_title
: com.android.internal.R.string.power_off)
.setMessage(resourceId)
.setPositiveButton(com.android.internal.R.string.yes, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// 开始一系列的关机流程，详见 6
beginShutdownSequence(context);
}
})
.setNegativeButton(com.android.internal.R.string.no, null)
.create();
closer.dialog = sConfirmDialog;
sConfirmDialog.setOnDismissListener(closer);
sConfirmDialog.getWindow().setType(WindowManager.LayoutParams.TYPE_KEYGUARD_DIALOG);
sConfirmDialog.show();
} else {
beginShutdownSequence(context);
}
}其中 config_longPressOnPowerBehavior 用来控制用户长按Power键触发的行为。
主要行为如下：
<!-- Control the behavior when the user long presses the power button.
0 - Nothing
1 - Global actions menu
2 - Power off (with confirmation)
3 - Power off (without confirmation)
4 - Go to voice assist
-->
<integer name="config_longPressOnPowerBehavior">1</integer>此源码 可以在 config.xml中查看，代码目录如下：frameworks\base\core\res\res\values\config.xml
4.CloseDialogReceiver 注册关机对话框广播
注册action 为ACTION_CLOSE_SYSTEM_DIALOGS广播接收器。
private static class CloseDialogReceiver extends BroadcastReceiver
implements DialogInterface.OnDismissListener {
private Context mContext;
public Dialog dialog;
CloseDialogReceiver(Context context) {
mContext = context;
IntentFilter filter = new IntentFilter(Intent.ACTION_CLOSE_SYSTEM_DIALOGS);
context.registerReceiver(this, filter);
}
@Override
public void onReceive(Context context, Intent intent) {
dialog.cancel();
}
public void onDismiss(DialogInterface unused) {
mContext.unregisterReceiver(this);
}
}5. new sConfirmDialog 显示关机对话框
Android原生关机对话框如下：
// 创建关机Dialg 详见 实现5
sConfirmDialog = new AlertDialog.Builder(context)
.setTitle(mRebootSafeMode
? com.android.internal.R.string.reboot_safemode_title
: com.android.internal.R.string.power_off)
.setMessage(resourceId)
.setPositiveButton(com.android.internal.R.string.yes, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// 开始一系列的关机流程，详见 6
beginShutdownSequence(context);
}
})
.setNegativeButton(com.android.internal.R.string.no, null)
.create();
closer.dialog = sConfirmDialog;
sConfirmDialog.setOnDismissListener(closer);
sConfirmDialog.getWindow().setType(WindowManager.LayoutParams.TYPE_KEYGUARD_DIALOG);
sConfirmDialog.show();6. beginShutdownSequence开始关机流程
beginShutdownSequence开始一系列关机流程，主要功能如下：
1.显示关机进度条对话框。
2.启动ShutdownThead 线程。
private static void beginShutdownSequence(Context context) {
synchronized (sIsStartedGuard) {
if (sIsStarted) {
Log.d(TAG, "Shutdown sequence already running, returning.");
return;
}
sIsStarted = true;
}
// 显示关机进度对话框 详见 7
sInstance.mProgressDialog = showShutdownDialog(context);
sInstance.mContext = context;
sInstance.mPowerManager = (PowerManager)context.getSystemService(Context.POWER_SERVICE);
// make sure we never fall asleep again
sInstance.mCpuWakeLock = null;
try {
sInstance.mCpuWakeLock = sInstance.mPowerManager.newWakeLock(
PowerManager.PARTIAL_WAKE_LOCK, TAG + "-cpu");
sInstance.mCpuWakeLock.setReferenceCounted(false);
sInstance.mCpuWakeLock.acquire();
} catch (SecurityException e) {
Log.w(TAG, "No permission to acquire wake lock", e);
sInstance.mCpuWakeLock = null;
}
// also make sure the screen stays on for better user experience
sInstance.mScreenWakeLock = null;
if (sInstance.mPowerManager.isScreenOn()) {
try {
sInstance.mScreenWakeLock = sInstance.mPowerManager.newWakeLock(
PowerManager.FULL_WAKE_LOCK, TAG + "-screen");
sInstance.mScreenWakeLock.setReferenceCounted(false);
sInstance.mScreenWakeLock.acquire();
} catch (SecurityException e) {
Log.w(TAG, "No permission to acquire wake lock", e);
sInstance.mScreenWakeLock = null;
}
}
if (SecurityLog.isLoggingEnabled()) {
SecurityLog.writeEvent(SecurityLog.TAG_OS_SHUTDOWN);
}
// 启动 关机线程 ，执行 Run 方法，详见 9
sInstance.mHandler = new Handler() {
};
sInstance.start();
}
7.showShutdownDialog 显示关机进度对话框
showShutdownDialog主要用来显示关机进度对话框
private static ProgressDialog showShutdownDialog(Context context) {
// Throw up a system dialog to indicate the device is rebooting / shutting down.
ProgressDialog pd = new ProgressDialog(context);
// Path 1: Reboot to recovery for update
// Condition: mReason startswith REBOOT_RECOVERY_UPDATE
//
// Path 1a: uncrypt needed
// Condition: if /cache/recovery/uncrypt_file exists but
// /cache/recovery/block.map doesn't.
// UI: determinate progress bar (mRebootHasProgressBar == True)
//
// * Path 1a is expected to be removed once the GmsCore shipped on
// device always calls uncrypt prior to reboot.
//
// Path 1b: uncrypt already done
// UI: spinning circle only (no progress bar)
//
// Path 2: Reboot to recovery for factory reset
// Condition: mReason == REBOOT_RECOVERY
// UI: spinning circle only (no progress bar)
//
// Path 3: Regular reboot / shutdown
// Condition: Otherwise
// UI: spinning circle only (no progress bar)
// mReason could be "recovery-update" or "recovery-update,quiescent".
if (mReason != null && mReason.startsWith(PowerManager.REBOOT_RECOVERY_UPDATE)) {
// We need the progress bar if uncrypt will be invoked during the
// reboot, which might be time-consuming.
mRebootHasProgressBar = RecoverySystem.UNCRYPT_PACKAGE_FILE.exists()
&& !(RecoverySystem.BLOCK_MAP_FILE.exists());
pd.setTitle(context.getText(com.android.internal.R.string.reboot_to_update_title));
if (mRebootHasProgressBar) {
pd.setMax(100);
pd.setProgress(0);
pd.setIndeterminate(false);
pd.setProgressNumberFormat(null);
pd.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
pd.setMessage(context.getText(
com.android.internal.R.string.reboot_to_update_prepare));
} else {
if (showSysuiReboot()) {
return null;
}
pd.setIndeterminate(true);
pd.setMessage(context.getText(
com.android.internal.R.string.reboot_to_update_reboot));
}
} else if (mReason != null && mReason.equals(PowerManager.REBOOT_RECOVERY)) {
if (RescueParty.isAttemptingFactoryReset()) {
// We're not actually doing a factory reset yet; we're rebooting
// to ask the user if they'd like to reset, so give them a less
// scary dialog message.
pd.setTitle(context.getText(com.android.internal.R.string.power_off));
pd.setMessage(context.getText(com.android.internal.R.string.shutdown_progress));
pd.setIndeterminate(true);
} else {
// Factory reset path. Set the dialog message accordingly.
pd.setTitle(context.getText(com.android.internal.R.string.reboot_to_reset_title));
pd.setMessage(context.getText(
com.android.internal.R.string.reboot_to_reset_message));
pd.setIndeterminate(true);
}
} else {
// 判断是否显示SystemUIReboot 详见 8
if (showSysuiReboot()) {
return null;
}
// 显示关机 进度对话框 详见 8
pd.setTitle(context.getText(com.android.internal.R.string.power_off));
pd.setMessage(context.getText(com.android.internal.R.string.shutdown_progress));
pd.setIndeterminate(true);
}
pd.setCancelable(false);
pd.getWindow().setType(WindowManager.LayoutParams.TYPE_KEYGUARD_DIALOG);
pd.show();
return pd;
}
关机 进度对话框实现
8.判断是否显示SystemUIReboot
showSysuiReboot 主要用来显示是否显示SystemUIReboot.
private static boolean showSysuiReboot() {
Log.d(TAG, "Attempting to use SysUI shutdown UI");
try {
StatusBarManagerInternal service = LocalServices.getService(
StatusBarManagerInternal.class);
if (service.showShutdownUi(mReboot, mReason)) {
// Sysui will handle shutdown UI.
Log.d(TAG, "SysUI handling shutdown UI");
return true;
}
} catch (Exception e) {
// If anything went wrong, ignore it and use fallback ui
}
Log.d(TAG, "SysUI is unavailable");
return false;
}
9.启动 关机线程 ，执行 Run 方法
在beginShutdownSequence方法中启动 关机线程。
private static void beginShutdownSequence(Context context) {
... ...
// static instance of this thread
private static final ShutdownThread sInstance = new ShutdownThread();
// start the thread that initiates shutdown
sInstance.mHandler = new Handler() {
};
sInstance.start();
... ...
}ShutdownThread Run 实现
ShutdownThread 主要作用：
1.发送有序的关机广播。
2.测量关闭某些项目的时间。
3.关闭ActivityManager。
4.关闭PackageManager。
5.关闭 Radios。
6.完成System Server 的关闭。
7.初始化并判定执行关机还是重启
/**
* Makes sure we handle the shutdown gracefully.
* Shuts off power regardless of radio state if the allotted time has passed.
*/
public void run() {
TimingsTraceLog shutdownTimingLog = newTimingsLog();
shutdownTimingLog.traceBegin("SystemServerShutdown");
metricShutdownStart();
metricStarted(METRIC_SYSTEM_SERVER);
BroadcastReceiver br = new BroadcastReceiver() {
@Override public void onReceive(Context context, Intent intent) {
// We don't allow apps to cancel this, so ignore the result.
actionDone();
}
};
/*
* Write a system property in case the system_server reboots before we
* get to the actual hardware restart. If that happens, we'll retry at
* the beginning of the SystemServer startup.
*/
{
String reason = (mReboot ? "1" : "0") + (mReason != null ? mReason : "");
SystemProperties.set(SHUTDOWN_ACTION_PROPERTY, reason);
}
/*
* If we are rebooting into safe mode, write a system property
* indicating so.
*/
if (mRebootSafeMode) {
SystemProperties.set(REBOOT_SAFEMODE_PROPERTY, "1");
}
metricStarted(METRIC_SEND_BROADCAST);
shutdownTimingLog.traceBegin("SendShutdownBroadcast");
Log.i(TAG, "Sending shutdown broadcast...");
// First send the high-level shut down broadcast.
mActionDone = false;
Intent intent = new Intent(Intent.ACTION_SHUTDOWN);
intent.addFlags(Intent.FLAG_RECEIVER_FOREGROUND | Intent.FLAG_RECEIVER_REGISTERED_ONLY);
// 发送 有序的 关机广播
mContext.sendOrderedBroadcastAsUser(intent,
UserHandle.ALL, null, br, mHandler, 0, null, null);
final long endTime = SystemClock.elapsedRealtime() + MAX_BROADCAST_TIME;
synchronized (mActionDoneSync) {
while (!mActionDone) {
long delay = endTime - SystemClock.elapsedRealtime();
if (delay <= 0) {
Log.w(TAG, "Shutdown broadcast timed out");
break;
} else if (mRebootHasProgressBar) {
int status = (int)((MAX_BROADCAST_TIME - delay) * 1.0 *
BROADCAST_STOP_PERCENT / MAX_BROADCAST_TIME);
sInstance.setRebootProgress(status, null);
}
try {
mActionDoneSync.wait(Math.min(delay, ACTION_DONE_POLL_WAIT_MS));
} catch (InterruptedException e) {
}
}
}
if (mRebootHasProgressBar) {
sInstance.setRebootProgress(BROADCAST_STOP_PERCENT, null);
}
// 测量 发送有序 关机广播所用的时间
shutdownTimingLog.traceEnd(); // SendShutdownBroadcast
metricEnded(METRIC_SEND_BROADCAST);
Log.i(TAG, "Shutting down activity manager...");
shutdownTimingLog.traceBegin("ShutdownActivityManager");
metricStarted(METRIC_AM);
// 关闭 Activity Manager
final IActivityManager am =
IActivityManager.Stub.asInterface(ServiceManager.checkService("activity"));
if (am != null) {
try {
am.shutdown(MAX_BROADCAST_TIME);
} catch (RemoteException e) {
}
}
if (mRebootHasProgressBar) {
sInstance.setRebootProgress(ACTIVITY_MANAGER_STOP_PERCENT, null);
}
shutdownTimingLog.traceEnd();// ShutdownActivityManager
metricEnded(METRIC_AM);
Log.i(TAG, "Shutting down package manager...");
shutdownTimingLog.traceBegin("ShutdownPackageManager");
metricStarted(METRIC_PM);
// 关闭 Package Manager
final PackageManagerService pm = (PackageManagerService)
ServiceManager.getService("package");
if (pm != null) {
pm.shutdown();
}
if (mRebootHasProgressBar) {
sInstance.setRebootProgress(PACKAGE_MANAGER_STOP_PERCENT, null);
}
shutdownTimingLog.traceEnd(); // ShutdownPackageManager
metricEnded(METRIC_PM);
// Shutdown radios.
shutdownTimingLog.traceBegin("ShutdownRadios");
metricStarted(METRIC_RADIOS);
//关闭 Radios shutdownRadios 详细 请看 10
shutdownRadios(MAX_RADIO_WAIT_TIME);
if (mRebootHasProgressBar) {
sInstance.setRebootProgress(RADIO_STOP_PERCENT, null);
}
shutdownTimingLog.traceEnd(); // ShutdownRadios
metricEnded(METRIC_RADIOS);
// 关闭 System Server
if (mRebootHasProgressBar) {
sInstance.setRebootProgress(MOUNT_SERVICE_STOP_PERCENT, null);
// If it's to reboot to install an update and uncrypt hasn't been
// done yet, trigger it now.
uncrypt();
}
shutdownTimingLog.traceEnd(); // SystemServerShutdown
metricEnded(METRIC_SYSTEM_SERVER);
saveMetrics(mReboot, mReason);
//初始化 并判断是关机还是重启 详见 11
rebootOrShutdown(mContext, mReboot, mReason);
}
10.shutdownRadios 关闭Radio 实现
shutdownRadios 用来关闭phone Radio相关内容 ，主要实现如下：
private void shutdownRadios(final int timeout) {
// If a radio is wedged, disabling it may hang so we do this work in another thread,
// just in case.
final long endTime = SystemClock.elapsedRealtime() + timeout;
final boolean[] done = new boolean[1];
//另起线程 异步关闭 Radios
Thread t = new Thread() {
public void run() {
TimingsTraceLog shutdownTimingsTraceLog = newTimingsLog();
boolean radioOff;
final ITelephony phone =
ITelephony.Stub.asInterface(ServiceManager.checkService("phone"));
try {
radioOff = phone == null || !phone.needMobileRadioShutdown();
if (!radioOff) {
Log.w(TAG, "Turning off cellular radios...");
metricStarted(METRIC_RADIO);
phone.shutdownMobileRadios();
}
} catch (RemoteException ex) {
Log.e(TAG, "RemoteException during radio shutdown", ex);
radioOff = true;
}
Log.i(TAG, "Waiting for Radio...");
long delay = endTime - SystemClock.elapsedRealtime();
while (delay > 0) {
if (mRebootHasProgressBar) {
int status = (int)((timeout - delay) * 1.0 *
(RADIO_STOP_PERCENT - PACKAGE_MANAGER_STOP_PERCENT) / timeout);
status += PACKAGE_MANAGER_STOP_PERCENT;
sInstance.setRebootProgress(status, null);
}
if (!radioOff) {
try {
radioOff = !phone.needMobileRadioShutdown();
} catch (RemoteException ex) {
Log.e(TAG, "RemoteException during radio shutdown", ex);
radioOff = true;
}
if (radioOff) {
Log.i(TAG, "Radio turned off.");
metricEnded(METRIC_RADIO);
shutdownTimingsTraceLog
.logDuration("ShutdownRadio", TRON_METRICS.get(METRIC_RADIO));
}
}
if (radioOff) {
Log.i(TAG, "Radio shutdown complete.");
done[0] = true;
break;
}
SystemClock.sleep(RADIOS_STATE_POLL_SLEEP_MS);
delay = endTime - SystemClock.elapsedRealtime();
}
}
};
//另起线程 异步关闭 Radios
t.start();
try {
t.join(timeout);
} catch (InterruptedException ex) {
}
if (!done[0]) {
Log.w(TAG, "Timed out waiting for Radio shutdown.");
}
}
11.rebootOrShutdown 初始化并决定关机还是重启
rebootOrShutdown主要用来 初始化并决定关机还是重启。
/**
* Do not call this directly. Use {@link #reboot(Context, String, boolean)}
* or {@link #shutdown(Context, String, boolean)} instead.
*
* @param context Context used to vibrate or null without vibration
* @param reboot true to reboot or false to shutdown
* @param reason reason for reboot/shutdown
*/
public static void rebootOrShutdown(final Context context, boolean reboot, String reason) {
String subsysProp;
subsysProp = SystemProperties.get("vendor.peripheral.shutdown_critical_list",
"ERROR");
//If we don't have the shutdown critical subsystem list we can't
//really do anything. Proceed with full system shutdown.
if (!subsysProp.equals("ERROR")) {
Log.i(TAG, "Shutdown critical subsyslist is :"+subsysProp+": ");
Log.i(TAG, "Waiting for a maximum of " +
(VENDOR_SUBSYS_MAX_WAIT_MS) + "ms");
String[] subsysList = subsysProp.split(" ");
int wait_count = 0;
boolean okToShutdown = true;
String subsysState;
int subsysListLength = subsysList.length;
do {
okToShutdown = true;
for (int i = 0; i < subsysListLength; i++) {
subsysState =
SystemProperties.get(
"vendor.peripheral." +
subsysList[i] +
".state",
"ERROR");
if(subsysState.equals("ONLINE")) {
//We only want to delay shutdown while
//one of the shutdown critical
//subsystems still shows as 'ONLINE'.
okToShutdown = false;
}
}
if (okToShutdown == false) {
SystemClock.sleep(VENDOR_SUBSYS_STATE_CHECK_INTERVAL_MS);
wait_count++;
}
} while (okToShutdown != true &&
wait_count < (VENDOR_SUBSYS_MAX_WAIT_MS/VENDOR_SUBSYS_STATE_CHECK_INTERVAL_MS));
if (okToShutdown != true) {
for (int i = 0; i < subsysList.length; i++) {
subsysState =
SystemProperties.get(
"vendor.peripheral." +
subsysList[i] +
".state",
"ERROR");
if(subsysState.equals("ONLINE")) {
Log.w(TAG, "Subsystem " + subsysList[i]+
"did not shut down within timeout");
}
}
} else {
Log.i(TAG, "Vendor subsystem(s) shutdown successful");
}
}
if (reboot) {
Log.i(TAG, "Rebooting, reason: " + reason);
PowerManagerService.lowLevelReboot(reason);
Log.e(TAG, "Reboot failed, will attempt shutdown instead");
reason = null;
} else if (SHUTDOWN_VIBRATE_MS > 0 && context != null) {
// vibrate before shutting down
Vibrator vibrator = new SystemVibrator(context);
try {
vibrator.vibrate(SHUTDOWN_VIBRATE_MS, VIBRATION_ATTRIBUTES);
} catch (Exception e) {
// Failure to vibrate shouldn't interrupt shutdown. Just log it.
Log.w(TAG, "Failed to vibrate during shutdown.", e);
}
// vibrator is asynchronous so we need to wait to avoid shutting down too soon.
try {
Thread.sleep(SHUTDOWN_VIBRATE_MS);
} catch (InterruptedException unused) {
}
}
// Shutdown power
Log.i(TAG, "Performing low-level shutdown...");
PowerManagerService.lowLevelShutdown(reason);
}
12. 关机log 分析
通过 链接adb,我们可以抓取关机的Log， 部分Log信息如下:
Line 96: 07-26 01:02:26.205 2510 3766 I AudioController: internalShutdown
Line 540: 07-26 01:02:30.968 790 790 D ShutdownThread: Notifying thread to start shutdown longPressBehavior=1
Line 540: 07-26 01:02:30.968 790 790 D ShutdownThread: Notifying thread to start shutdown longPressBehavior=1
Line 541: 07-26 01:02:30.970 790 790 D ShutdownThread: Attempting to use SysUI shutdown UI
Line 541: 07-26 01:02:30.970 790 790 D ShutdownThread: Attempting to use SysUI shutdown UI
Line 542: 07-26 01:02:30.971 790 790 D ShutdownThread: SysUI handling shutdown UI
Line 542: 07-26 01:02:30.971 790 790 D ShutdownThread: SysUI handling shutdown UI
Line 555: 07-26 01:02:30.997 790 3902 I ShutdownThread: Sending shutdown broadcast...
Line 555: 07-26 01:02:30.997 790 3902 I ShutdownThread: Sending shutdown broadcast...
Line 561: 07-26 01:02:31.014 790 790 W SyncManager: Writing sync state before shutdown...
Line 666: 07-26 01:02:31.436 2510 3766 I AudioController: internalShutdown
Line 669: 07-26 01:02:31.443 790 790 I StatsCompanionService: StatsCompanionService noticed a shutdown.
Line 708: 07-26 01:02:31.671 790 3902 D ShutdownTiming: SendShutdownBroadcast took to complete: 675ms
Line 708: 07-26 01:02:31.671 790 3902 D ShutdownTiming: SendShutdownBroadcast took to complete: 675ms
Line 711: 07-26 01:02:31.671 790 3902 I ShutdownThread: Shutting down activity manager...
Line 740: 07-26 01:02:31.954 790 3902 W AppOps : Writing app ops before shutdown...
Line 771: 07-26 01:02:32.152 790 3902 W BatteryStats: Writing battery stats before shutdown...
Line 806: 07-26 01:02:32.386 790 1015 W system_server: Long monitor contention with owner Thread-29 (3902) at void com.android.server.am.BatteryStatsService.shutdown()(BatteryStatsService.java:249) waiters=0 in void com.android.server.am.BatteryStatsService.noteProcessStart(java.lang.String, int) for 132ms
Line 840: 07-26 01:02:32.507 790 3902 W ProcessStatsService: Writing process stats before shutdown...
Line 850: 07-26 01:02:32.563 790 3902 D ShutdownTiming: ShutdownActivityManager took to complete: 891ms
Line 850: 07-26 01:02:32.563 790 3902 D ShutdownTiming: ShutdownActivityManager took to complete: 891ms
Line 853: 07-26 01:02:32.563 790 3902 I ShutdownThread: Shutting down package manager...
Line 872: 07-26 01:02:32.656 790 3902 D ShutdownTiming: ShutdownPackageManager took to complete: 93ms
Line 872: 07-26 01:02:32.656 790 3902 D ShutdownTiming: ShutdownPackageManager took to complete: 93ms
Line 879: 07-26 01:02:32.677 1804 1976 V PhoneInterfaceManager: [PhoneIntfMgr] 1 Phones are shutdown.
Line 882: 07-26 01:02:32.678 790 3951 I ShutdownThread: Waiting for Radio...
Line 883: 07-26 01:02:32.679 790 3951 I ShutdownThread: Radio shutdown complete.
Line 883: 07-26 01:02:32.679 790 3951 I ShutdownThread: Radio shutdown complete.
Line 884: 07-26 01:02:32.681 790 3902 D ShutdownTiming: ShutdownRadios took to complete: 25ms
Line 884: 07-26 01:02:32.681 790 3902 D ShutdownTiming: ShutdownRadios took to complete: 25ms
Line 885: 07-26 01:02:32.681 790 3902 D ShutdownTiming: SystemServerShutdown took to complete: 1705ms
Line 885: 07-26 01:02:32.681 790 3902 D ShutdownTiming: SystemServerShutdown took to complete: 1705ms
Line 886: 07-26 01:02:32.684 790 3902 I ShutdownThread: Shutdown critical subsyslist is :modem :
Line 886: 07-26 01:02:32.684 790 3902 I ShutdownThread: Shutdown critical subsyslist is :modem :
Line 887: 07-26 01:02:32.684 790 3902 I ShutdownThread: Waiting for a maximum of 10000ms
Line 888: 07-26 01:02:32.684 790 3902 I ShutdownThread: Vendor subsystem(s) shutdown successful
Line 888: 07-26 01:02:32.684 790 3902 I ShutdownThread: Vendor subsystem(s) shutdown successful
Line 931: 07-26 01:02:33.192 790 3902 I ShutdownThread: Performing low-level shutdown...
Line 931: 07-26 01:02:33.192 790 3902 I ShutdownThread: Performing low-level shutdown...
Line 1003: 07-26 01:02:33.543 565 585 E Dpps : ProcessAlMsg():471 Shutdown event recieved quit -108
Line 1005: 07-26 01:02:33.543 565 585 I Dpps : ProcessNextEvent():142 Shutdown notification quit processing
Line 1009: 07-26 01:02:33.562 565 583 E Dpps : ProcessAbaMsg():579 Shutdown event recieved quit -108至此，本篇已结束，如有不对的地方，欢迎您的建议与指正。同时期待您的关注，感谢您的阅读，谢谢！