[Android Pro] 分析 Package manager has died

reference to : http://blog.csdn.net/xxooyc/article/details/50162523

这是今天遇到的一个issue,由于Binder造成的。虽然比较简单,还是保持记录下吧。

先来开看一下Crash log:

    E/HpnsService(24810): HPNS Version is 5.0java.lang.RuntimeException: Package manager has died  
    E/HpnsService(24810):   at android.app.ApplicationPackageManager.getPackageInfo(ApplicationPackageManager.java:111)  
    E/HpnsService(24810):   at com.xx.xxx.util.AppUtil.checkInstalledPackageVersionCode(AppUtil.java:568)  
    E/HpnsService(24810):   at com.xx.xxx.util.AppUtil.checkAppStatus(AppUtil.java:653)  
    E/HpnsService(24810):   at com.xx.xxx.view.AppListView$LoadingAppThread.run(AppListView.java:723)  
    E/HpnsService(24810): Caused by: android.os.TransactionTooLargeException  
    E/HpnsService(24810):   at android.os.BinderProxy.transactNative(Native Method)  
    E/HpnsService(24810):   at android.os.BinderProxy.transact(Binder.java:496)  
    E/HpnsService(24810):   at android.content.pm.IPackageManager$Stub$Proxy.getPackageInfo(IPackageManager.java:1786)  
    E/HpnsService(24810):   at android.app.ApplicationPackageManager.getPackageInfo(ApplicationPackageManager.java:106)  
    E/HpnsService(24810):   ... 3 more  

 

为什么会发生Package manager has died?

frameworks/base/core/java/Android/app/ApplicationPackageManager.java:

102    @Override
103    public PackageInfo getPackageInfo(String packageName, int flags)
104            throws NameNotFoundException {
105        try {
106            PackageInfo pi = mPM.getPackageInfo(packageName, flags, mContext.getUserId());
107            if (pi != null) {
108                return pi;
109            }
110        } catch (RemoteException e) {
111            throw new RuntimeException("Package manager has died", e);
112        }
113
114        throw new NameNotFoundException(packageName);
115    }

 这是一个Binder调用,造成这个的原因是因为发生了RemoteException。


那为什么友会发生RemoteException?

其实也就是下面的这句Caused by: android.os.TransactionTooLargeException造成的。


为什么会造成TransactionTooLargeException?

frameworks/base/core/jni/android_util_Binder.cpp:

 

    682        case FAILED_TRANSACTION:  
    683            ALOGE("!!! FAILED BINDER TRANSACTION !!!");  
    684            // TransactionTooLargeException is a checked exception, only throw from certain methods.  
    685            // FIXME: Transaction too large is the most common reason for FAILED_TRANSACTION  
    686            //        but it is not the only one.  The Binder driver can return BR_FAILED_REPLY  
    687            //        for other reasons also, such as if the transaction is malformed or  
    688            //        refers to an FD that has been closed.  We should change the driver  
    689            //        to enable us to distinguish these cases in the future.  
    690            jniThrowException(env, canThrowRemoteException  
    691                    ? "android/os/TransactionTooLargeException"  
    692                            : "java/lang/RuntimeException", NULL);  
    693            break;  

 
可以看出如果Binder的使用超出了一个进程的限制就会抛出TransactionTooLargeException这个异常。

如果是其他原因造成Binder crash的话就会抛出RuntimeException。


那一个进程的Binder内存限制是多少?

frameworks/native/libs/binder/ProcessState.cpp:

44 #define BINDER_VM_SIZE ((1*1024*1024) - (4096 *2))  

 这便是一个进程中binder的大小,大约1M。

给Binder分配内存的代码:

    349#if !defined(HAVE_WIN32_IPC)  
    350        // mmap the binder, providing a chunk of virtual address space to receive transactions.  
    351        mVMStart = mmap(0, BINDER_VM_SIZE, PROT_READ, MAP_PRIVATE | MAP_NORESERVE, mDriverFD, 0);  
    352        if (mVMStart == MAP_FAILED) {  
    353            // *sigh*  
    354            ALOGE("Using /dev/binder failed: unable to mmap transaction memory.\n");  
    355            close(mDriverFD);  
    356            mDriverFD = -1;  
    357        }  

 

通过上面的清理,知道了如果一个进程中使用的Binder内容超过了1M,就会crash.

而如果这时候恰巧在用getPackageManager()做事情,就会提示Package manager has died。


可以事实真的是这样的吗?

写了个demo来证明一下:

    public class MainActivity extends Activity {  
      
        @Override  
        protected void onCreate(Bundle savedInstanceState) {  
            super.onCreate(savedInstanceState);  
            setContentView(R.layout.activity_main);  
            test();  
        }  
      
        private void test() {  
            for (int i = 0; i < 2; i++) {  
            new Thread() {  
                @Override  
                public void run() {  
                    int count = 0;  
                        List<PackageInfo> list = getPackageManager()  
                                .getInstalledPackages(10000);  
                        for (PackageInfo info : list) {  
                            if(count >=1000){  
                                break;  
                            }  
                            try {  
                                PackageInfo pi = getPackageManager()  
                                        .getPackageInfo(info.packageName,  
                                                PackageManager.GET_ACTIVITIES);  
                                Log.e("yanchen", "yanchen threadid:"+Thread.currentThread().getId()   
                                        + ",i:" + count++);  
                            } catch (NameNotFoundException e) {  
                            }  
                    }  
                }  
            }.start();  
        }  
        }  
    }  

 

这个Demo就是同时创建两个线程来进行Binder调用.

运行打印的log:

    E/yanchen (21180): yanchen threadid:4097,i:271  
    E/yanchen (21180): yanchen threadid:4097,i:272  
    E/yanchen (21180): yanchen threadid:4097,i:273  
    E/yanchen (21180): yanchen threadid:4097,i:274  
    E/yanchen (21180): yanchen threadid:4097,i:275  
    E/yanchen (21180): yanchen threadid:4097,i:276  

 
此时也如预期发生了Crash:

    E/JavaBinder(31244): !!! FAILED BINDER TRANSACTION !!!  
    E/AndroidRuntime(31244): FATAL EXCEPTION: Thread-4798  
    E/AndroidRuntime(31244): Process: com.example.testdl, PID: 31244  
    E/AndroidRuntime(31244): java.lang.RuntimeException: Package manager has died  
    E/AndroidRuntime(31244):    at android.app.ApplicationPackageManager.getPackageInfo(ApplicationPackageManager.java:155)  
    E/AndroidRuntime(31244):    at com.example.testdl.MainActivity$1.run(MainActivity.java:40)  
    E/AndroidRuntime(31244): Caused by: android.os.TransactionTooLargeException  
    E/AndroidRuntime(31244):    at android.os.BinderProxy.transactNative(Native Method)  
    E/AndroidRuntime(31244):    at android.os.BinderProxy.transact(Binder.java:496)  
    E/AndroidRuntime(31244):    at android.content.pm.IPackageManager$Stub$Proxy.getPackageInfo(IPackageManager.java:2208)  
    E/AndroidRuntime(31244):    at android.app.ApplicationPackageManager.getPackageInfo(ApplicationPackageManager.java:150)  
    E/AndroidRuntime(31244):    ... 1 more  
    D/EnterpriseDeviceManagerService( 3021): isMana  

 

解决方式:

     其实只要避免多个线程同时来调用Binder就可以了,毕竟一个线程用了会释放,所以理论上是很难发生的。

修改后的Demo:

    synchronized(MainActivity.class){  
        PackageInfo pi = getPackageManager()  
                .getPackageInfo(info.packageName,  
                        PackageManager.GET_ACTIVITIES);  
    }  

 

再次运行就不会Crash了。

 

posted @ 2017-02-28 11:53  demoblog  阅读(727)  评论(0编辑  收藏  举报