diff --git a/mcs/README.md b/mcs/README.md
index fd83a2050c9d57928256937ce21e6fc6c0347ced..128cbc22731fa3d024350c278897834f143645fa 100644
--- a/mcs/README.md
+++ b/mcs/README.md
@@ -88,10 +88,8 @@ OpenAMP包括如下三大重要组件：
 #### 用户开发
 参考demo实现流程，当前提供了多个API，包含在libopenamp.a中，供用户使用和二次开发，用户无需感知openamp实现细节。
 
-1.  调用openamp_init，初始化remoteproc、virtio、rpmsg。
+1.  调用openamp_init，初始化remoteproc、virtio、rpmsg，Linux端与Client OS建立配对的endpoint，供消息收发使用。
 
-2.  调用bringup_endpoint，启动endpoint动态配对，Linux端与Client OS建立配对的endpoint，供消息收发使用。
+2.  调用receive_message、send_message收发消息。
 
-3.  调用receive_message、send_message收发消息。
-
-4.  调用openamp_deinit，释放openamp资源。
\ No newline at end of file
+3.  调用openamp_deinit，释放openamp资源。
\ No newline at end of file
diff --git a/mcs/modules/openamp_module.c b/mcs/modules/openamp_module.c
index e23a85b8d366c8f87172c870e495edc184aca256..20ce22aed37c380b63a954c540ec8af14132e1fd 100644
--- a/mcs/modules/openamp_module.c
+++ b/mcs/modules/openamp_module.c
@@ -39,6 +39,8 @@ int openamp_init(void)
 {
     int ret;
     struct remoteproc *rproc;
+    unsigned char message[100];
+    int len;
 
     rproc = create_remoteproc();
     if (!rproc) {
@@ -61,6 +63,8 @@ int openamp_init(void)
     sleep(5);  /* wait for zephyr booting */
     virtio_init();
 
+    (void)receive_message(message, sizeof(message), &len);  /* name service: endpoint matching */
+
     return 0;
 }
 
diff --git a/mcs/modules/openamp_module.h b/mcs/modules/openamp_module.h
index f5be2bf02617125bf4119a1fde5fb5046da025b7..69abb2c93fdd6ebc397d0aacb0bd1e131e502479 100644
--- a/mcs/modules/openamp_module.h
+++ b/mcs/modules/openamp_module.h
@@ -9,7 +9,16 @@
 extern char *target_binfile;
 extern char *target_binaddr;
 
+/* initialize openamp module, including remoteproc, virtio, rpmsg */
 int openamp_init(void);
+
+/* release openamp resource */
 int openamp_deinit(void);
 
+/* message standard receive interface */
+int receive_message(unsigned char *message, int message_len, int *real_len);
+
+/* message standard send interface */
+int send_message(unsigned char *message, int len);
+
 #endif
\ No newline at end of file
diff --git a/mcs/modules/rpmsg_module.c b/mcs/modules/rpmsg_module.c
index 5078f14e28267095cc4ee72517c546967fd51634..a97c34bb4625c261ddf3330f07761a1fac5de38d 100644
--- a/mcs/modules/rpmsg_module.c
+++ b/mcs/modules/rpmsg_module.c
@@ -6,16 +6,7 @@
 
 static unsigned char received_data[2048] = {0};
 static unsigned int received_len = 0;
-struct rpmsg_endpoint *ep;   /* current using endpoint */
-
-void bringup_endpoint(struct rpmsg_endpoint *ept_inst)
-{
-	unsigned char message[100];
-	int len;
-
-    ep = ept_inst;
-    (void)receive_message(message, sizeof(message), &len);  /* name service: endpoint matching */
-}
+struct rpmsg_endpoint ept_inst;
 
 int endpoint_cb(struct rpmsg_endpoint *ept, void *data,
 		size_t len, uint32_t src, void *priv)
@@ -29,12 +20,12 @@ int endpoint_cb(struct rpmsg_endpoint *ept, void *data,
 static void rpmsg_service_unbind(struct rpmsg_endpoint *ept)
 {
 	(void)ept;
-	rpmsg_destroy_ept(ep);
+	rpmsg_destroy_ept(&ept_inst);
 }
 
 void ns_bind_cb(struct rpmsg_device *rdev, const char *name, uint32_t dest)
 {
-	(void)rpmsg_create_ept(ep, rdev, name,
+	(void)rpmsg_create_ept(&ept_inst, rdev, name,
 			RPMSG_ADDR_ANY, dest,
 			endpoint_cb,
 			rpmsg_service_unbind);
@@ -94,5 +85,5 @@ _cleanup:
 
 int send_message(unsigned char *message, int len)
 {
-	return rpmsg_send(ep, message, len);
+	return rpmsg_send(&ept_inst, message, len);
 }
diff --git a/mcs/modules/rpmsg_module.h b/mcs/modules/rpmsg_module.h
index ddeee24cf0ec818614d53b19b929e96cde959469..cb700df2c41d9b8ce4344154eaaed7f4e2c3178e 100644
--- a/mcs/modules/rpmsg_module.h
+++ b/mcs/modules/rpmsg_module.h
@@ -8,13 +8,4 @@
 /* callback of ns */
 void ns_bind_cb(struct rpmsg_device *rdev, const char *name, uint32_t dest);
 
-/* bringup a endpoint, receive_message and send_message are based on this */
-void bringup_endpoint(struct rpmsg_endpoint *ept_inst);
-
-/* message standard receive interface */
-int receive_message(unsigned char *message, int message_len, int *real_len);
-
-/* message standard send interface */
-int send_message(unsigned char *message, int len);
-
 #endif
\ No newline at end of file
diff --git a/mcs/openamp_demo/rpmsg_main.c b/mcs/openamp_demo/rpmsg_main.c
index 857327d264c1d47af1431bf74a2670db883df6f2..cd467e42f51447ea72f1dc6f1ceb0ef7c9996cc1 100644
--- a/mcs/openamp_demo/rpmsg_main.c
+++ b/mcs/openamp_demo/rpmsg_main.c
@@ -10,15 +10,9 @@ char *target_binaddr;
 int rpmsg_app_master(void)
 {
     int ret;
-    unsigned int message = 0;
-    int len;
-    struct rpmsg_endpoint ept_inst;
 
     printf("start processing OpenAMP demo...\n");
 
-    /* To ensure thread saftety, endpoint instance should be a local variable */
-    bringup_endpoint(&ept_inst);
-
     while (message < 99) {
         ret = send_message((unsigned char*)&message, sizeof(message));
         if (ret < 0) {
diff --git a/mcs/rpmsg_pty_demo/rpmsg_main.c b/mcs/rpmsg_pty_demo/rpmsg_main.c
index 0ca15596af26928f2861a82deb4a5ff7503428c2..3bf642ed830df31d8fdad99bec765ae65b009b61 100644
--- a/mcs/rpmsg_pty_demo/rpmsg_main.c
+++ b/mcs/rpmsg_pty_demo/rpmsg_main.c
@@ -1,5 +1,6 @@
 #include <stdio.h>
 #include <stdarg.h>
+#include <pthread.h>
 #include "rpmsg_pty.h"
 #include "openamp_module.h"
 
@@ -14,13 +15,22 @@ int rpmsg_app_master(void)
 
     printf("Multi-thread processing user requests...\n");
 
-    /* zephyr shell, open with screen */
+    pthread_mutex_init(&mutex, NULL);
+
+    /* userA, zephyr shell, open with screen */
     if (pthread_create(&tida, NULL, shell_user, NULL) < 0) {
         perror("userA pthread_create");
         return -1;
     }
     pthread_detach(tida);
 
+    /* userB, zephyr shell, open with screen */
+    if (pthread_create(&tidb, NULL, shell_user, NULL) < 0) {
+        perror("userB pthread_create");
+        return -1;
+    }
+    pthread_detach(tidb);
+
     while (1);
 
     return 0;
diff --git a/mcs/rpmsg_pty_demo/rpmsg_pty.c b/mcs/rpmsg_pty_demo/rpmsg_pty.c
index 90e1d8409682cb86cfc8617ed651c440b112d726..900e634276c7e0cb3dc07a890bd0e4b1a1ef032c 100644
--- a/mcs/rpmsg_pty_demo/rpmsg_pty.c
+++ b/mcs/rpmsg_pty_demo/rpmsg_pty.c
@@ -5,10 +5,13 @@
 #include <errno.h>
 #include <unistd.h>
 #include <string.h>
+#include <pthread.h>
 #include "openamp_module.h"
 
 /* define the keys according to your terminfo */
-#define KEY_CTRL_C      3
+#define KEY_CTRL_D      4
+
+pthread_mutex_t mutex;
 
 void open_pty(int *pfdm, int *pfds, const char *pty_name)
 {
@@ -43,10 +46,6 @@ void *shell_user(void *arg)
     unsigned char cmd[1];
     unsigned char reply[2048];
     int reply_len;
-    struct rpmsg_endpoint ept_inst;
-
-    /* To ensure thread saftety, endpoint instance should be defined in thread */
-    bringup_endpoint(&ept_inst);
 
     open_pty(&fdm, &fds, "shell");
 
@@ -57,21 +56,21 @@ void *shell_user(void *arg)
             return (void*)-1;
         }
 
-        if (cmd[0] == KEY_CTRL_C) {  /* special key: ctrl+c */
+        if (cmd[0] == KEY_CTRL_D) {  /* special key: ctrl+d */
             close(fds);
             close(fdm);
             return (void*)0;  /* exit this thread, the same as pthread_exit */
         }
 
+        pthread_mutex_lock(&mutex);
+
         ret = send_message(cmd, 1);  /* send command to rtos */
-        if (ret < 0) {
-            printf("shell_user: send_message(%s) failed: %d\n", cmd, ret);
-            return (void*)-1;
-        }
+        ret |= receive_message(reply, sizeof(reply), &reply_len);   /* receive reply from rtos */
+
+        pthread_mutex_unlock(&mutex);
 
-        ret = receive_message(reply, sizeof(reply), &reply_len);   /* receive reply from rtos */
         if (ret < 0) {
-            printf("shell_user: receive_message failed: %d\n", ret);
+            printf("shell_user: send(%s)/receive(%s) message failed: %d\n", cmd, reply, ret);
             return (void*)-1;
         }
 
@@ -91,10 +90,6 @@ void *console_user(void *arg)
     int fdm, fds;
     unsigned char reply[2048];
     int reply_len;
-    struct rpmsg_endpoint ept_inst;
-
-    /* To ensure thread saftety, endpoint instance should be defined in thread */
-    bringup_endpoint(&ept_inst);
 
     /* open PTY, pts binds to terminal, using screen to open pts */
     open_pty(&fdm, &fds, "console");
@@ -123,10 +118,6 @@ void *log_user(void *arg)
     unsigned char log[2048] = {0};
     int log_len;
     const char *log_file = "/tmp/zephyr_log.txt";
-    struct rpmsg_endpoint ept_inst;
-
-    /* To ensure thread saftety, endpoint instance should be defined in thread */
-    bringup_endpoint(&ept_inst);
 
     ret = receive_message(log, sizeof(log), &log_len);   /* receive log from rtos */
     if (ret < 0) {
diff --git a/mcs/rpmsg_pty_demo/rpmsg_pty.h b/mcs/rpmsg_pty_demo/rpmsg_pty.h
index b3f3399e1fecbf6e4e7e2799040618728eb9b602..3668849dda9cc7b6b91cda516049bfe08e198f6a 100644
--- a/mcs/rpmsg_pty_demo/rpmsg_pty.h
+++ b/mcs/rpmsg_pty_demo/rpmsg_pty.h
@@ -5,4 +5,6 @@ void *shell_user(void *arg);
 void *console_user(void *arg);
 void *log_user(void *arg);
 
+extern pthread_mutex_t mutex;
+
 #endif
\ No newline at end of file