--- src/sys/kern/lwkt_msgport.c	2008/11/22 11:03:35	1.53
+++ src/sys/kern/lwkt_msgport.c	2008/11/26 15:05:42	1.54
@@ -225,6 +225,7 @@ _lwkt_initport(lwkt_port_t port,
 {
     bzero(port, sizeof(*port));
     TAILQ_INIT(&port->mp_msgq);
+    TAILQ_INIT(&port->mp_msgq_prio);
     port->mp_getport = gportfn;
     port->mp_putport = pportfn;
     port->mp_waitmsg =  wmsgfn;
@@ -361,10 +362,16 @@ static __inline
 void
 _lwkt_pullmsg(lwkt_port_t port, lwkt_msg_t msg)
 {
+    lwkt_msg_queue *queue;
+
     /*
      * normal case, remove and return the message.
      */
-    TAILQ_REMOVE(&port->mp_msgq, msg, ms_node);
+    if (__predict_false(msg->ms_flags & MSGF_PRIORITY))
+	queue = &port->mp_msgq_prio;
+    else
+	queue = &port->mp_msgq;
+    TAILQ_REMOVE(queue, msg, ms_node);
     msg->ms_flags &= ~MSGF_QUEUED;
 }
 
@@ -372,14 +379,29 @@ static __inline
 void
 _lwkt_pushmsg(lwkt_port_t port, lwkt_msg_t msg)
 {
+    lwkt_msg_queue *queue;
+
     msg->ms_flags |= MSGF_QUEUED;
-    TAILQ_INSERT_TAIL(&port->mp_msgq, msg, ms_node);
+    if (__predict_false(msg->ms_flags & MSGF_PRIORITY))
+	queue = &port->mp_msgq_prio;
+    else
+    	queue = &port->mp_msgq;
+    TAILQ_INSERT_TAIL(queue, msg, ms_node);
 }
 
 static __inline
 lwkt_msg_t
 _lwkt_pollmsg(lwkt_port_t port)
 {
+    lwkt_msg_t msg;
+
+    msg = TAILQ_FIRST(&port->mp_msgq_prio);
+    if (__predict_false(msg != NULL))
+	return msg;
+
+    /*
+     * Priority queue has no message, fallback to non-priority queue.
+     */
     return TAILQ_FIRST(&port->mp_msgq);
 }