3 files changed, 28 insertions, 0 deletions
diff --git a/src/chmsg.c b/src/chmsg.c
index 61546d7c1..20a59904e 100644
--- a/src/chmsg.c
+++ b/src/chmsg.c
@@ -36,7 +36,14 @@ t_msg chMsgSend(Thread *tp, t_msg msg) {
 
   chSysLock();
 
+#ifdef CH_USE_MESSAGES_PRIORITY
+  if (tp->p_flags & P_MSGBYPRIO)
+    prio_insert(currp, &tp->p_msgqueue);
+  else
+    fifo_insert(currp, &tp->p_msgqueue);
+#else
   fifo_insert(currp, &tp->p_msgqueue);
+#endif
   currp->p_msg = msg;
   if (tp->p_state == PRWTMSG)
     chSchReadyI(tp, RDY_OK);
@@ -67,7 +74,14 @@ t_msg chMsgSendWithEvent(Thread *tp, t_msg msg, EventSource *esp) {
   chSysLock();
 
   chDbgAssert(tp->p_state != PRWTMSG, "chmsg.c, chMsgSendWithEvent()");
+#ifdef CH_USE_MESSAGES_PRIORITY
+  if (tp->p_flags & P_MSGBYPRIO)
+    prio_insert(currp, &tp->p_msgqueue);
+  else
+    fifo_insert(currp, &tp->p_msgqueue);
+#else
   fifo_insert(currp, &tp->p_msgqueue);
+#endif
   chEvtSendI(esp);
   currp->p_msg = msg;
   chSchGoSleepS(PRSNDMSG);
@@ -107,7 +121,14 @@ t_msg chMsgSendTimeout(Thread *tp, t_msg msg, t_time time) {
   chSysLock();
 
   chVTSetI(&vt, time, wakeup, currp);
+#ifdef CH_USE_MESSAGES_PRIORITY
+  if (tp->p_flags & P_MSGBYPRIO)
+    prio_insert(currp, &tp->p_msgqueue);
+  else
+    fifo_insert(currp, &tp->p_msgqueue);
+#else
   fifo_insert(currp, &tp->p_msgqueue);
+#endif
   if (tp->p_state == PRWTMSG)
     chSchReadyI(tp, RDY_OK);
   currp->p_msg = msg;
diff --git a/src/include/threads.h b/src/include/threads.h
index 50468e063..f451278cf 100644
--- a/src/include/threads.h
+++ b/src/include/threads.h
@@ -135,6 +135,8 @@ struct Thread {
 #define P_TERMINATE 1
 /** Thread option: Create suspended thread.*/
 #define P_SUSPENDED 2
+/** Thread option: Serve messages by priority instead of FIFO order.*/
+#define P_MSGBYPRIO 4
 
 /** Pseudo priority used by the ready list header, do not use.*/
 #define NOPRIO      0
diff --git a/src/templates/chconf.h b/src/templates/chconf.h
index fb8ae6a69..d8e5f88da 100644
--- a/src/templates/chconf.h
+++ b/src/templates/chconf.h
@@ -108,6 +108,11 @@
  * @note requires \p CH_USE_VIRTUAL_TIMERS.*/
 #define CH_USE_MESSAGES_EVENT
 
+/** Configuration option: If enabled then the threads have an option to serve
+ *  messages by priority instead of FIFO order.
+ * @note requires \p CH_USE_MESSAGES.*/
+#define CH_USE_MESSAGES_PRIORITY
+
 /** Configuration option: if specified then the
  *  \p chThdGetExitEventSource() function is included in the kernel.
  * @note requires \p CH_USE_MESSAGES.