SystemServer

PackageManagerService

http://blog.sina.com.cn/s/blog_3e3fcadd01014678.html
- PackageManger
- Permission
Main Tasks
- 建立installer与installd的socket连接
- 建立PackageHandler消息循环: 用于处理外部的apk安装等请求
- 解析/system/etc/permissionsetc/permissions/"（一般就是/system/etc/permissions）下的各个.xml文件中读取系统的基本permissions，而且文件platform.xml在最后读，表明其优先级最高
  - Android的基本permission、Linux gid(s)、以及它们的对应关系 -- mSettings.mPermissions， mGlobalGids
  - 为Android permission指定的Linux uid -- mSystemPermissions
  - 为Android所增加的应用需要链接的java库的名称和全路径 -- mSharedLibraries
  - 系统所支持的各种硬件模块的feature(未见具体实例，据代码可知，这只是一个名字) -- mAvailableFeatures
- 解析/data/system/packages.xml文件
- 对jar进行dexopt优化
- 通过ScanDirLI()扫描并解析当前已存在的apk
- 将解析/安装的.apk信息保存到/data/system/packages.xml和/data/system/packages.lst文件以备查询

HowToStart

RuntimeInit.zygoteInit
- 调用 com.android.server.SystemServer类的main函数
  - init1
    - system_init(System_init.cpp)
      - Start Surface Flinger
      - Start Sensor Service
      - com/android/server/SystemServer::init2
        
        Thread thr = new ServerThread();
        
        thr.start
      - ProcessState::self()->startThreadPool();
      - IPCThreadState::self()->joinThreadPool();
thr.start
- ServerThread::run
  - Start Services
    - Watchdog
      - battery
      - power
      - alarm
      - activity
    - Input Manager
      - start
    - windowmanager
      - main
  - ready
    - wm
      - displayReady
      - systemReady

Debug

Crash
- System server fault
  - Zygote会重新启动SystemServer
  - 主要原因
    - Watchdog
      - killed a system_server process because of deadlock in of services it's running
      - In rare cases watchdog can be timed out because of high memory and CPU usage.
      - 存在形式
        
        system_process thread
        
        watchdog
        
        com.android.server.Watchdog.run
    - Fatal exception occured in one of system services
      - a hardware issue
- Kernel panic
  - Device reboot
  - dmesg

文章目录

1 SystemServer

创建@

2013-03-31

最后修改@

2014-01-03

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