常见问题修改方法

[SYSTEM-SERVER] Avoid a dead lock between ActivityManager and PowerManager services
 "main" prio=5 tid=1 Blocked | group="main"
  sCount=1 dsCount=0 obj=0x73fbbfa8 self=0x7ff7b3024000 
  | sysTid=3219 nice=-2 cgrp=default sched=0/0 handle=0x7ff7b6f853e0 
  | state=S schedstat=( 2270057780 115981310 8889 ) utm=149 stm=77 core=0 HZ=100 |
   stack=0x7fff62c6e000-0x7fff62c70000 stackSize=8MB 
   | held mutexes= at com.android.server.am.ActivityManagerService.registerReceiver(ActivityManagerService.java:15583) - waiting to lock <0x016a0e36> (a com.android.server.am.ActivityManagerService) --> 
   synchronized(this): lock held by thread 29 at
    android.app.ContextImpl.registerReceiverInternal(ContextImpl.java:1655) 
    at android.app.ContextImpl.registerReceiver(ContextImpl.java:1623) 
    at com.android.server.power.PowerManagerService.systemReady(PowerManagerService.java:522) - locked <0x1e40b137> (a java.lang.Object) --> 
    synchronized(mLock) at com.android.server.SystemServer.startOtherServices(SystemServer.java:1054) at com.android.server.SystemServer.run(SystemServer.java:263) 
    at com.android.server.SystemServer.main(SystemServer.java:177) at java.lang.reflect.Method.invoke!(Native method) at java.lang.reflect.Method.invoke(Method.java:372)
     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:901) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:696) 
     "InputDispatcher" prio=10 tid=29 Blocked | group="main"
      sCount=1 dsCount=0 obj=0x12fb50a0 self=0x7ff7a9656200 
      | sysTid=3418 nice=-8 cgrp=default sched=0/0 handle=0x7ff7a9511400 
      | state=S schedstat=( 3081453 618956 33 ) utm=0 stm=0 core=0 HZ=100 
      | stack=0x7ff79f104000-0x7ff79f106000 stackSize=1012KB 
      | held mutexes= at com.android.server.power.PowerManagerService.setUserActivityTimeoutOverrideFromWindowManagerInternal(PowerManagerService.java:2317) 
      - waiting to lock <0x1e40b137> (a java.lang.Object --> synchronized(mLock):
       lock held by thread 1 at com.android.server.power.PowerManagerService.access$5600(PowerManagerService.java:84) 
       at com.android.server.power.PowerManagerService$LocalService.setUserActivityTimeoutOverrideFromWindowManager(PowerManagerService.java:3277)
        at com.android.server.wm.WindowManagerService.performLayoutAndPlaceSurfacesLockedInner(WindowManagerService.java:10110)
         at com.android.server.wm.WindowManagerService.performLayoutAndPlaceSurfacesLockedLoop(WindowManagerService.java:8789)
          at com.android.server.wm.WindowManagerService.performLayoutAndPlaceSurfacesLocked(WindowManagerService.java:8731)
           at com.android.server.wm.WindowManagerService.setNewConfiguration(WindowManagerService.java:3934) 
           - locked <0x0b892c09> (a java.util.HashMap) at com.android.server.am.ActivityManagerService.updateConfigurationLocked(ActivityManagerService.java:16785)
            at com.android.server.am.ActivityManagerService.updateConfiguration(ActivityManagerService.java:16668) 
            - locked <0x016a0e36> (a com.android.server.am.ActivityManagerService) --> synchronized(this) 
            at com.android.server.wm.WindowManagerService.sendNewConfiguration(WindowManagerService.java:7053) 
            at com.android.server.wm.InputMonitor.notifyConfigurationChanged(InputMonitor.java:331) 
            at com.android.server.input.InputManagerService.notifyConfigurationChanged(InputManagerService.java:1385) 

修改方法

frameworks/base / services/java/com/android/server/SystemServer.java

  添加synchronred线程同步

try {
            // Need to synchronize with ActivityManagerService before locking on mPowerManagerService.mlock
            // to avoid a possible dead lock with InputDispatcher.
            synchronized (mActivityManagerService) {
                // TODO: use boot phase
                mPowerManagerService.systemReady(mActivityManagerService.getAppOpsService());
            }
        } catch (Throwable e) {
            reportWtf("making Power Manager Service ready", e);
        }

问题2：

Root cause: This is a abnormal case.The system will kill the process even if the activity which belong to the process is being launched.
If the appDiedLock function is caled after the startActivityMayWait function.
AMS will consider the process is still alive.But the process is died in fact. So there is an exception when AMS call scheduleLaunchActivity
.and then AMS will restart the process. But before do it, 
AMS will clean all the activity records which belong to the old process. After do this, 
There will be no activity belongs to the process in AMS's history. After the process restart,
we can see AMS want to start activity which is the top of the AMS's history stack.
And the activity should belong to the process.But from the analysis before,
There is no activity belongs to the process.So there is no activity to launch.
This will lead there is no focuse activity in system then cause ANR. 
Solution: this is workaround fix. Add a flag in ActivityRecord,When this abnormal case appear,
set the flag.and when AMS clean the activity stack,Reserve the ActivityRecord object according to the added flag.

修改代码路径

services/java/com/android/server/am/ActivityManagerService.java

services/java/com/android/server/am/ActivityRecord.java

services/java/com/android/server/am/ActivityStack.java

思路：因为OOM的时候杀死了一些进程导致OOM

添加判断条件在handleAppDiedLocked不kill掉一些进程。

问题3：清除掉已经被kill的应用的资源

 JAVACRASH on system.server java.lang.OutOfMemoryError at android.os.FileUtils.readTextFile

WindowManagerService: Cleanup the starting window resources 
When an application dies very early after being launched, some resources ViewRootImpl are left in system_server. 
This patch removes those resources when the window is removed from WindowManagerService.

   public void removeWindowLocked(Session session, WindowState win) {
        

        ...
        if ( (win.mAppToken != null) && (win.mAppToken.startingView != null) ) {
            View view = win.mAppToken.startingView;
            win.mAppToken.startingView = null;
            mPolicy.removeStartingWindow(null, view);
        }
      ...
}
 
   
 
   
 
   

 
   
 问题4：当一个应用升级了，应该删除对应之前不需要的apk的odex文件 
   
 
   
diff --git a/services/core/java/com/android/server/pm/PackageManagerService.java b/services/core/java/com/android/server/pm/PackageManagerService.java
			index f645d42..1525d35 100644
			--- a/services/core/java/com/android/server/pm/PackageManagerService.java
			+++ b/services/core/java/com/android/server/pm/PackageManagerService.java
			@@ -1826,23 +1826,21 @@
	1826	1826	 
	1827	1827	             if (systemServerClassPath != null) {
	1828	1828	                 String[] systemServerClassPathElements = splitString(systemServerClassPath, ':');
	1829	1829	                 for (String element : systemServerClassPathElements) {
	1830	1830	                     alreadyDexOpted.add(element);
	1831	1831	                 }
	1832	1832	             } else {
	1833	1833	                 Slog.w(TAG, "No SYSTEMSERVERCLASSPATH found!");
	1834	1834	             }
	1835	1835	 
	1836		-            final List allInstructionSets = getAllInstructionSets();
	1837		-            final String[] dexCodeInstructionSets =
	1838		-                getDexCodeInstructionSets(allInstructionSets.toArray(new String[allInstructionSets.s
ize()]));
		1836	+            final String[] dexCodeInstructionSets = InstructionSets.getAllDexCodeInstructionSets();
	1839	1837	 
	1840	1838	             /**
	1841	1839	              * Ensure all external libraries have had dexopt run on them.
	1842	1840	              */
	1843	1841	             if (mSharedLibraries.size() > 0) {
	1844	1842	                 // NOTE: For now, we're compiling these system "shared libraries"
	1845	1843	                 // (and framework jars) into all available architectures. It's possible
	1846	1844	                 // to compile them only when we come across an app that uses them (there's
	1847	1845	                 // already logic for that in scanPackageLI) but that adds some complexity.
	1848	1846	                 SELECTIVE_ENABLED = SystemProperties.getBoolean("persist.selective.enabled", DEFAULT
_SELECTIVE_ENABLED);
			@@ -11262,20 +11260,27 @@
	11262	11260	                     res.setError(INSTALL_FAILED_SHARED_USER_INCOMPATIBLE,
	11263	11261	                             "Forbidding shared user change from " + oldPkgSetting.sharedUser
	11264	11262	                             + " to " + newPkgSetting.sharedUser);
	11265	11263	                     updatedSettings = true;
	11266	11264	                 }
	11267	11265	             }
	11268	11266	 
	11269	11267	             if (res.returnCode == PackageManager.INSTALL_SUCCEEDED) {
	11270	11268	                 updateSettingsLI(newPackage, installerPackageName, allUsers, perUserInstalled, res);
	11271	11269	                 updatedSettings = true;
		11270	+
		11271	+                // Remove existing odex in /data
		11272	+                final String[] dexCodeIsas = InstructionSets.getAllDexCodeInstructionSets();
		11273	+                for (String dexCodeIsa : dexCodeIsas) {
		11274	+                    mInstaller.rmdex(deletedPackage.applicationInfo.sourceDir,
		11275	+                            dexCodeIsa);
		11276	+                }
	11272	11277	             }
	11273	11278	 
	11274	11279	         } catch (PackageManagerException e) {
	11275	11280	             res.setError("Package couldn't be installed in " + pkg.codePath, e);
	11276	11281	         }
	11277	11282	 
	11278	11283	         if (res.returnCode != PackageManager.INSTALL_SUCCEEDED) {
	11279	11284	             // Re installation failed. Restore old information
	11280	11285	             // Remove new pkg information
	11281	11286	             if (newPackage != null) {