Merge "Reduce lock contention." into tm-dev

core/java/android/app/ApplicationPackageManager.java

@@ -165,51 +165,36 @@ public class ApplicationPackageManager extends PackageManager {
     public static final String PERMISSION_CONTROLLER_RESOURCE_PACKAGE =
             "com.android.permissioncontroller";
 
-    private final Object mLock = new Object();
+    private volatile UserManager mUserManager;
-
+    private volatile PermissionManager mPermissionManager;
-    @GuardedBy("mLock")
+    private volatile PackageInstaller mInstaller;
-    private UserManager mUserManager;
+    private volatile ArtManager mArtManager;
-    @GuardedBy("mLock")
+    private volatile DevicePolicyManager mDevicePolicyManager;
-    private PermissionManager mPermissionManager;
+    private volatile String mPermissionsControllerPackageName;
-    @GuardedBy("mLock")
-    private PackageInstaller mInstaller;
-    @GuardedBy("mLock")
-    private ArtManager mArtManager;
-    @GuardedBy("mLock")
-    private DevicePolicyManager mDevicePolicyManager;
 
     @GuardedBy("mDelegates")
     private final ArrayList<MoveCallbackDelegate> mDelegates = new ArrayList<>();
 
-    @GuardedBy("mLock")
-    private String mPermissionsControllerPackageName;
-
     UserManager getUserManager() {
-        synchronized (mLock) {
         if (mUserManager == null) {
             mUserManager = UserManager.get(mContext);
         }
         return mUserManager;
     }
-    }
 
     DevicePolicyManager getDevicePolicyManager() {
-        synchronized (mLock) {
         if (mDevicePolicyManager == null) {
             mDevicePolicyManager = mContext.getSystemService(DevicePolicyManager.class);
         }
         return mDevicePolicyManager;
     }
-    }
 
     private PermissionManager getPermissionManager() {
-        synchronized (mLock) {
         if (mPermissionManager == null) {
             mPermissionManager = mContext.getSystemService(PermissionManager.class);
         }
         return mPermissionManager;
     }
-    }
 
     @Override
     public int getUserId() {
@@ -851,7 +836,6 @@ public class ApplicationPackageManager extends PackageManager {
      */
     @Override
     public String getPermissionControllerPackageName() {
-        synchronized (mLock) {
         if (mPermissionsControllerPackageName == null) {
             try {
                 mPermissionsControllerPackageName = mPM.getPermissionControllerPackageName();
@@ -861,7 +845,6 @@ public class ApplicationPackageManager extends PackageManager {
         }
         return mPermissionsControllerPackageName;
     }
-    }
 
     /**
      * @hide
@@ -3235,7 +3218,6 @@ public class ApplicationPackageManager extends PackageManager {
 
     @Override
     public PackageInstaller getPackageInstaller() {
-        synchronized (mLock) {
         if (mInstaller == null) {
             try {
                 mInstaller = new PackageInstaller(mPM.getPackageInstaller(),
@@ -3246,7 +3228,6 @@ public class ApplicationPackageManager extends PackageManager {
         }
         return mInstaller;
     }
-    }
 
     @Override
     public boolean isPackageAvailable(String packageName) {
@@ -3583,7 +3564,6 @@ public class ApplicationPackageManager extends PackageManager {
 
     @Override
     public ArtManager getArtManager() {
-        synchronized (mLock) {
         if (mArtManager == null) {
             try {
                 mArtManager = new ArtManager(mContext, mPM.getArtManager());
@@ -3593,7 +3573,6 @@ public class ApplicationPackageManager extends PackageManager {
         }
         return mArtManager;
     }
-    }
 
     @Override
     public String getDefaultTextClassifierPackageName() {

services/core/java/com/android/server/pm/PackageManagerService.java

@@ -6692,6 +6692,11 @@ public class PackageManagerService extends IPackageManager.Stub
 
     @Override
     public IPackageInstaller getPackageInstaller() {
+        // Return installer service for internal calls.
+        if (PackageManagerServiceUtils.isSystemOrRoot()) {
+            return mInstallerService;
+        }
+        // Return null for InstantApps.
         if (getInstantAppPackageName(Binder.getCallingUid()) != null) {
             return null;
         }

services/core/java/com/android/server/pm/PackageManagerServiceUtils.java

@@ -1249,6 +1249,14 @@ public class PackageManagerServiceUtils {
         }
     }
 
+    /**
+     * Check if the Binder caller is system UID or root's UID.
+     */
+    public static boolean isSystemOrRoot() {
+        final int uid = Binder.getCallingUid();
+        return uid == Process.SYSTEM_UID || uid == Process.ROOT_UID;
+    }
+
     /**
      * Enforces that only the system UID or root's UID can call a method exposed
      * via Binder.
@@ -1257,8 +1265,7 @@ public class PackageManagerServiceUtils {
      * @throws SecurityException if the caller is not system or root
      */
     public static void enforceSystemOrRoot(String message) {
-        final int uid = Binder.getCallingUid();
+        if (!isSystemOrRoot()) {
-        if (uid != Process.SYSTEM_UID && uid != Process.ROOT_UID) {
             throw new SecurityException(message);
         }
     }