记一次App异常kill分析处理
由于Android版本的迭代更新速度非常快，所以Android版本上的一些新功能可能会导致你以前OK的代码，会发生一些意想不到的的问题，今天这里所说的就是一次由于Android时间的设置改变然后导致App被异常kill的情况。我在这里只想说这个问题，开始的时候弄得我都要给整疯了，咋也找不出原因。
注意：该问题讲解是在Android版本7.xx
问题现象描述
最近测试开发组，反馈一个问题说在测试部App中调用时间设置接口先将时间设置到2000年，然后再将时间设置回当前时间，在这个过程中会出现测试App异常退出，被kill掉了。原来是以为Native错误或者是AndroidRuntime错误，可是这些都不是。然后测试部将问题提给固件组，然我们进行解决。下面就开始分析一下相关的解决步骤：
1.异常日志
12-31 23:59:59.467 578 1234 W CustomerManager/OsCustomerMade: ++++paxtest setSpTime result = 0
12-31 23:59:59.468 578 1234 E AlarmManager: set time workaroud logd restart!!! oldMillis 1573460821291 millis 978278399289
12-31 23:59:59.468 578 668 V AlarmManager: Time changed notification from kernel; rebatching
12-31 23:59:59.468 578 668 V AlarmManager: remove(operation) changed bounds; rebatching
12-31 23:59:59.470 2515 2901 D paxlog : Java_pax_util_OsPaxApi_SetTime result=0
12-31 23:59:59.470 2515 2901 E DBG : RtcTest-> setTime after
12-31 23:59:59.470 2515 2901 E RtcTest : setTime after
12-31 23:59:59.469 578 668 V AlarmManager: remove(operation) changed bounds; rebatching
12-31 23:59:59.471 578 668 V AlarmManager: set(PendingIntent{5160c70: PendingIntentRecord{cd9be9 android broadcastIntent}}) : type=3 triggerAtTime=1811335 win=0 tElapsed=1815806 maxElapsed=1815806 interval=0 flags=0x1
12-31 23:59:59.472 578 668 D AlarmManagerService: set alarm to kernel: 1815.806000000, type=3
12-31 23:59:59.472 578 668 V AlarmManager: set(PendingIntent{c42906e: PendingIntentRecord{36d330f android broadcastIntent}}) : type=1 triggerAtTime=978278400000 win=0 tElapsed=1815806 maxElapsed=1815806 interval=0 flags=0x1
12-31 23:59:59.473 578 668 D BroadcastQueue: Add broadcast <BroadcastRecord{960b8da u-1 android.intent.action.TIME_SET}> into [parallel | background], pending size 0
12-31 23:59:59.473 578 668 D BroadcastQueue: Add broadcast <BroadcastRecord{91d510b u-1 android.intent.action.TIME_SET}> into [ordered | background], pending size 0
12-31 23:59:59.473 578 668 D BroadcastQueue: Header is BroadcastRecord{91d510b u-1 android.intent.action.TIME_SET} now
12-31 23:59:59.474 578 668 D AlarmManager: triggerList.size = 0, hasWakeup = false
12-31 23:59:59.475 578 578 D ConditionProviders.SCP: onReceive android.intent.action.TIME_SET
12-31 23:59:59.475 578 592 D BroadcastQueue: Done with parallel broadcast [background] [BroadcastRecord{960b8da u-1 android.intent.action.TIME_SET}]
12-31 23:59:59.476 578 578 D ConditionProviders.SCP: notifyCondition condition://android/schedule?days=6.7&start=23.30&end=10.0&exitAtAlarm=false STATE_FALSE reason=!meetsSchedule
12-31 23:59:59.475 765 765 D KeyguardUpdateMonitor: received broadcast android.intent.action.TIME_SET
12-31 23:59:59.476 765 951 D Clock : onReceive action=android.intent.action.TIME_SET
12-31 23:59:59.477 765 951 D Clock : onReceive action=android.intent.action.TIME_SET
12-31 23:59:59.480 1164 1164 D ServiceReceiver: action android.intent.action.TIME_SET
12-31 23:59:59.483 578 578 D ConditionProviders.SCP: notifyCondition condition://android/schedule?days=1.2.3.4.5&start=22.0&end=7.0&exitAtAlarm=false STATE_TRUE reason=meetsSchedule
12-31 23:59:59.503 578 592 I ActivityManager: Start proc 2902:com.android.deskclock/1000 for broadcast com.android.deskclock/.AlarmInitReceiver
12-31 23:59:59.505 578 578 V AlarmManager: remove(operation) changed bounds; rebatching
12-31 23:59:59.506 578 578 D AlarmManagerService: set alarm to kernel: 1811.334000000, type=3
12-31 23:59:59.506 765 765 D KeyguardUpdateMonitor: handleTimeUpdate
12-31 23:59:59.506 578 1234 V AlarmManager: set(PendingIntent{9af0be8: PendingIntentRecord{298f201 com.android.providers.calendar broadcastIntent}}) : type=2 triggerAtTime=1815840 win=0 tElapsed=1815840 maxElapsed=1815840 interval=0 flags=0x1
12-31 23:59:59.506 578 578 D ConditionProviders.SCP: Scheduling evaluate for Mon Jan 01 07:00:00 GMT+08:00 2001 (978303600000), in +7h0m0s525ms, now=Sun Dec 31 23:59:59 GMT+08:00 2000 (978278399475)
12-31 23:59:59.507 578 1234 D AlarmManagerService: set alarm to kernel: 1815.840000000, type=2
12-31 23:59:59.507 578 578 V AlarmManager: set(PendingIntent{2a188a6: PendingIntentRecord{5287781 android broadcastIntent}}) : type=0 triggerAtTime=978303600000 win=0 tElapsed=27011334 maxElapsed=27011334 interval=0 flags=0x9
//异常被杀
12-31 23:59:59.510 578 810 I ActivityManager: remove task id:16, callingUid:10021, callingPid:765
12-31 23:59:59.512 2902 2902 W zygote : Using default instruction set features for ARM CPU variant (generic) using conservative defaults
12-31 23:59:59.513 765 765 D Clock : updateClock updateClock=下午11:59
12-31 23:59:59.516 765 765 D Clock : updateClock updateClock=下午11:59
12-31 23:59:59.527 2515 2515 E DBG : BaseActivity-> onDestroy MainActivity
12-31 23:59:59.557 578 810 I ActivityManager: remove task id:17, callingUid:10021, callingPid:765
12-31 23:59:59.803 578 948 D PowerController.AppState: - reportAppProcStateInfo() E -
12-31 23:59:59.804 578 949 D PowerController.RecogA: handleMessage(MSG_REPORT_EVENT)
12-31 23:59:59.827 2902 2902 I AlarmClock: AlarmInitReceiver android.intent.action.TIME_SET
//通过kill -9 将2515进程杀掉
12-31 23:59:59.843 2515 2515 I Process : Sending signal. PID: 2515 SIG: 9
12-31 23:59:59.984 578 663 I ActivityManager: Process com.pax.ft (pid 2515) has died: fore +7TOP
2.异常日志分析
刚看到这段异常日志你是否也感到懵逼，怎么好好的App就异常退出了(从实际感官来看)，然后日志里面没有任何的DEBUG和AndroidRuntime错误，从日志12-31 23:59:59.527 2515 2515 E DBG : BaseActivity-> onDestroy MainActivity可以看到Activity走到了onDestroy 的流程，这个看像是正常退出，但是这个是谁发出的指令将该App杀了呢。我真个日志足足分析了一天然后没有任何进展，但是bug要解决，怎么办呢，继续啃日志，然后突然看到一段日志，如下：
12-31 23:59:59.510 578 810 I ActivityManager: remove task id:16, callingUid:10021, callingPid:765
11-11 16:26:58.651 578 1234 I ActivityManager: START u0 {flg=0x10804000 cmp=com.android.systemui/.recents.RecentsActivity} from uid 10021, pid 765
可以看到ActivityManager有将task id为16的进程remove了，然后接着查找日志可以看到10021为SystemUI进程，且id:16恰好是我们的异常kill的App了，那么这就好办了。搜寻SystemUI看哪里调用到了removeTask。
3.确定原因
最后在frameworks/base/packages/SystemUI/./src/com/android/systemui/recents/RecentsActivity.java找到了如下的代码，可以看到监听了时间的变化，然后根据oldLastStackActiveTime 来判断是否需要将当前的task要remove掉。
/**
* Broadcast receiver to handle messages from the system
*/
final BroadcastReceiver mSystemBroadcastReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context ctx, Intent intent) {
String action = intent.getAction();
if (action.equals(Intent.ACTION_SCREEN_OFF)) {
// When the screen turns off, dismiss Recents to Home
dismissRecentsToHomeIfVisible(false);
} else if (action.equals(Intent.ACTION_TIME_CHANGED)) {
// If the time shifts but the currentTime >= lastStackActiveTime, then that boundary
// is still valid. Otherwise, we need to reset the lastStackactiveTime to the
// currentTime and remove the old tasks in between which would not be previously
// visible, but currently would be in the new currentTime
int currentUser = SystemServicesProxy.getInstance(RecentsActivity.this)
.getCurrentUser();
long oldLastStackActiveTime = Settings.Secure.getLongForUser(getContentResolver(),
Secure.OVERVIEW_LAST_STACK_ACTIVE_TIME, -1, currentUser);
if (oldLastStackActiveTime != -1) {
long currentTime = System.currentTimeMillis();
if (currentTime < oldLastStackActiveTime) {
// We are only removing tasks that are between the new current time
// and the old last stack active time, they were not visible and in the
// TaskStack so we don't need to remove any associated TaskViews but we do
// need to load the task id's from the system
RecentsTaskLoadPlan loadPlan = Recents.getTaskLoader().createLoadPlan(ctx);
loadPlan.preloadRawTasks(false /* includeFrontMostExcludedTask */);
List<ActivityManager.RecentTaskInfo> tasks = loadPlan.getRawTasks();
for (int i = tasks.size() - 1; i >= 0; i--) {
ActivityManager.RecentTaskInfo task = tasks.get(i);
if (currentTime <= task.lastActiveTime && task.lastActiveTime <
oldLastStackActiveTime) {
Recents.getSystemServices().removeTask(task.persistentId);
}
}
Settings.Secure.putLongForUser(RecentsActivity.this.getContentResolver(),
Secure.OVERVIEW_LAST_STACK_ACTIVE_TIME, currentTime, currentUser);
}
}
}
}
};
