diff --git a/include/binder/IPCThreadState.h b/include/binder/IPCThreadState.h
index 60c2242..1853cff 100644
--- a/include/binder/IPCThreadState.h
+++ b/include/binder/IPCThreadState.h
@@ -76,14 +76,18 @@
                                                         BpBinder* proxy); 
 
     static  void                shutdown();
-    
+
     // Call this to disable switching threads to background scheduling when
     // receiving incoming IPC calls.  This is specifically here for the
     // Android system process, since it expects to have background apps calling
     // in to it but doesn't want to acquire locks in its services while in
     // the background.
     static  void                disableBackgroundScheduling(bool disable);
-    
+
+            // Call blocks until the number of executing binder threads is less than
+            // the maximum number of binder threads threads allowed for this process.
+            void                blockUntilThreadAvailable();
+
 private:
                                 IPCThreadState();
                                 ~IPCThreadState();
@@ -101,9 +105,9 @@
             status_t            getAndExecuteCommand();
             status_t            executeCommand(int32_t command);
             void                processPendingDerefs();
-            
+
             void                clearCaller();
-            
+
     static  void                threadDestructor(void *st);
     static  void                freeBuffer(Parcel* parcel,
                                            const uint8_t* data, size_t dataSize,
@@ -114,7 +118,7 @@
     const   pid_t               mMyThreadId;
             Vector<BBinder*>    mPendingStrongDerefs;
             Vector<RefBase::weakref_type*> mPendingWeakDerefs;
-            
+
             Parcel              mIn;
             Parcel              mOut;
             status_t            mLastError;
diff --git a/include/binder/ProcessState.h b/include/binder/ProcessState.h
index 3bc978d..f9edc2a 100644
--- a/include/binder/ProcessState.h
+++ b/include/binder/ProcessState.h
@@ -24,6 +24,8 @@
 
 #include <utils/threads.h>
 
+#include <pthread.h>
+
 // ---------------------------------------------------------------------------
 namespace android {
 
@@ -71,25 +73,33 @@
                                 ProcessState(const ProcessState& o);
             ProcessState&       operator=(const ProcessState& o);
             String8             makeBinderThreadName();
-            
+
             struct handle_entry {
                 IBinder* binder;
                 RefBase::weakref_type* refs;
             };
-            
+
             handle_entry*       lookupHandleLocked(int32_t handle);
 
             int                 mDriverFD;
             void*               mVMStart;
-            
+
+            // Protects thread count variable below.
+            pthread_mutex_t     mThreadCountLock;
+            pthread_cond_t      mThreadCountDecrement;
+            // Number of binder threads current executing a command.
+            size_t              mExecutingThreadsCount;
+            // Maximum number for binder threads allowed for this process.
+            size_t              mMaxThreads;
+
     mutable Mutex               mLock;  // protects everything below.
-            
+
             Vector<handle_entry>mHandleToObject;
 
             bool                mManagesContexts;
             context_check_func  mBinderContextCheckFunc;
             void*               mBinderContextUserData;
-            
+
             KeyedVector<String16, sp<IBinder> >
                                 mContexts;