Merge "Added watchdog monitor for Binder threads availability."

6 files changed, 26 insertions, 3 deletions

diff --git a/api/current.txt b/api/current.txt
index b307d61..9b47519 100644
--- a/api/current.txt
+++ b/api/current.txt
@@ -22499,6 +22499,7 @@ package android.os {
   public class Binder implements android.os.IBinder {
     ctor public Binder();
     method public void attachInterface(android.os.IInterface, java.lang.String);
+    method public static final void blockUntilThreadAvailable();
     method public static final long clearCallingIdentity();
     method public void dump(java.io.FileDescriptor, java.lang.String[]);
     method protected void dump(java.io.FileDescriptor, java.io.PrintWriter, java.lang.String[]);
diff --git a/api/system-current.txt b/api/system-current.txt
index 9184d8b..3fd3517 100644
--- a/api/system-current.txt
+++ b/api/system-current.txt
@@ -24387,6 +24387,7 @@ package android.os {
   public class Binder implements android.os.IBinder {
     ctor public Binder();
     method public void attachInterface(android.os.IInterface, java.lang.String);
+    method public static final void blockUntilThreadAvailable();
     method public static final long clearCallingIdentity();
     method public void dump(java.io.FileDescriptor, java.lang.String[]);
     method protected void dump(java.io.FileDescriptor, java.io.PrintWriter, java.lang.String[]);
diff --git a/core/java/android/os/Binder.java b/core/java/android/os/Binder.java
index b4a4624..b77b82c 100644
--- a/core/java/android/os/Binder.java
+++ b/core/java/android/os/Binder.java
@@ -187,6 +187,12 @@ public class Binder implements IBinder {
     }
 
     /**
+     * Call blocks until the number of executing binder threads is less
+     * than the maximum number of binder threads allowed for this process.
+     */
+    public static final native void blockUntilThreadAvailable();
+
+    /**
      * Default constructor initializes the object.
      */
     public Binder() {
diff --git a/core/jni/android_util_Binder.cpp b/core/jni/android_util_Binder.cpp
index 5f42c3d..cfbedda 100644
--- a/core/jni/android_util_Binder.cpp
+++ b/core/jni/android_util_Binder.cpp
@@ -807,6 +807,11 @@ static void android_os_Binder_destroy(JNIEnv* env, jobject obj)
     }
 }
 
+static void android_os_Binder_blockUntilThreadAvailable(JNIEnv* env, jobject clazz)
+{
+    return IPCThreadState::self()->blockUntilThreadAvailable();
+}
+
 // ----------------------------------------------------------------------------
 
 static const JNINativeMethod gBinderMethods[] = {
@@ -819,7 +824,8 @@ static const JNINativeMethod gBinderMethods[] = {
     { "getThreadStrictModePolicy", "()I", (void*)android_os_Binder_getThreadStrictModePolicy },
     { "flushPendingCommands", "()V", (void*)android_os_Binder_flushPendingCommands },
     { "init", "()V", (void*)android_os_Binder_init },
-    { "destroy", "()V", (void*)android_os_Binder_destroy }
+    { "destroy", "()V", (void*)android_os_Binder_destroy },
+    { "blockUntilThreadAvailable", "()V", (void*)android_os_Binder_blockUntilThreadAvailable }
 };
 
 const char* const kBinderPathName = "android/os/Binder";
diff --git a/services/core/java/com/android/server/Watchdog.java b/services/core/java/com/android/server/Watchdog.java
index 794e1b0..69e61f6 100644
--- a/services/core/java/com/android/server/Watchdog.java
+++ b/services/core/java/com/android/server/Watchdog.java
@@ -46,7 +46,6 @@ import java.util.ArrayList;
 /** This class calls its monitor every minute. Killing this process if they don't return **/
 public class Watchdog extends Thread {
     static final String TAG = "Watchdog";
-    static final boolean localLOGV = false || false;
 
     // Set this to true to use debug default values.
     static final boolean DB = false;
@@ -73,7 +72,7 @@ public class Watchdog extends Thread {
     static Watchdog sWatchdog;
 
     /* This handler will be used to post message back onto the main thread */
-    final ArrayList<HandlerChecker> mHandlerCheckers = new ArrayList<HandlerChecker>();
+    final ArrayList<HandlerChecker> mHandlerCheckers = new ArrayList<>();
     final HandlerChecker mMonitorChecker;
     ContentResolver mResolver;
     ActivityManagerService mActivity;
diff --git a/services/core/java/com/android/server/am/ActivityManagerService.java b/services/core/java/com/android/server/am/ActivityManagerService.java
index b606353..37f0e35 100644
--- a/services/core/java/com/android/server/am/ActivityManagerService.java
+++ b/services/core/java/com/android/server/am/ActivityManagerService.java
@@ -2179,6 +2179,15 @@ public final class ActivityManagerService extends ActivityManagerNative
         }
     }
 
+    public static final class BinderThreadMonitor implements Watchdog.Monitor {
+        /** This method will block until there is a binder thread available to process
+         * in coming IPCs to make sure other processes can still communicate with the service.
+         */
+        @Override
+        public void monitor() {
+            Binder.blockUntilThreadAvailable();
+        }
+    }
     // Note: This method is invoked on the main thread but may need to attach various
     // handlers to other threads.  So take care to be explicit about the looper.
     public ActivityManagerService(Context systemContext) {
@@ -2273,6 +2282,7 @@ public final class ActivityManagerService extends ActivityManagerNative
         };
 
         Watchdog.getInstance().addMonitor(this);
+        Watchdog.getInstance().addMonitor(new BinderThreadMonitor());
         Watchdog.getInstance().addThread(mHandler);
     }