score: Fine grained locking for message queues

Aggregate several critical sections into a bigger one.  Sending and
receiving messages is now protected by an ISR lock.  Thread dispatching
is only disabled in case a blocking operation is necessary.  The message
copy procedure is done inside the critical section (interrupts
disabled).  Thus this change may have a negative impact on the interrupt
latency in case very large messages are transferred.

Update #2273.

6 files changed, 57 insertions, 17 deletions

diff --git a/cpukit/rtems/include/rtems/rtems/messageimpl.h b/cpukit/rtems/include/rtems/rtems/messageimpl.h
index fa9e573892..2399d65f29 100644
--- a/cpukit/rtems/include/rtems/rtems/messageimpl.h
+++ b/cpukit/rtems/include/rtems/rtems/messageimpl.h
@@ -139,6 +139,21 @@ RTEMS_INLINE_ROUTINE Message_queue_Control *_Message_queue_Get (
      _Objects_Get( &_Message_queue_Information, id, location );
 }
 
+RTEMS_INLINE_ROUTINE Message_queue_Control *
+_Message_queue_Get_interrupt_disable(
+  Objects_Id         id,
+  Objects_Locations *location,
+  ISR_lock_Context  *lock_context
+)
+{
+  return (Message_queue_Control *) _Objects_Get_isr_disable(
+    &_Message_queue_Information,
+    id,
+    location,
+    lock_context
+  );
+}
+
 RTEMS_INLINE_ROUTINE Message_queue_Control *_Message_queue_Allocate( void )
 {
   return (Message_queue_Control *)
diff --git a/cpukit/rtems/src/msgqbroadcast.c b/cpukit/rtems/src/msgqbroadcast.c
index 64ea80e3de..aabbf3f6ac 100644
--- a/cpukit/rtems/src/msgqbroadcast.c
+++ b/cpukit/rtems/src/msgqbroadcast.c
@@ -40,6 +40,7 @@ rtems_status_code rtems_message_queue_broadcast(
   Message_queue_Control          *the_message_queue;
   Objects_Locations               location;
   CORE_message_queue_Status       core_status;
+  ISR_lock_Context                lock_context;
 
   if ( !buffer )
     return RTEMS_INVALID_ADDRESS;
@@ -47,7 +48,11 @@ rtems_status_code rtems_message_queue_broadcast(
   if ( !count )
     return RTEMS_INVALID_ADDRESS;
 
-  the_message_queue = _Message_queue_Get( id, &location );
+  the_message_queue = _Message_queue_Get_interrupt_disable(
+    id,
+    &location,
+    &lock_context
+  );
   switch ( location ) {
 
     case OBJECTS_LOCAL:
@@ -61,10 +66,9 @@ rtems_status_code rtems_message_queue_broadcast(
                       #else
                         NULL,
                       #endif
-                      count
+                      count,
+                      &lock_context
                     );
-
-      _Objects_Put( &the_message_queue->Object );
       return
         _Message_queue_Translate_core_message_queue_return_code( core_status );
 
diff --git a/cpukit/rtems/src/msgqflush.c b/cpukit/rtems/src/msgqflush.c
index 7ae7ef4544..809c243b52 100644
--- a/cpukit/rtems/src/msgqflush.c
+++ b/cpukit/rtems/src/msgqflush.c
@@ -54,16 +54,23 @@ rtems_status_code rtems_message_queue_flush(
 {
   Message_queue_Control          *the_message_queue;
   Objects_Locations               location;
+  ISR_lock_Context                lock_context;
 
   if ( !count )
     return RTEMS_INVALID_ADDRESS;
 
-  the_message_queue = _Message_queue_Get( id, &location );
+  the_message_queue = _Message_queue_Get_interrupt_disable(
+    id,
+    &location,
+    &lock_context
+  );
   switch ( location ) {
 
     case OBJECTS_LOCAL:
-      *count = _CORE_message_queue_Flush( &the_message_queue->message_queue );
-      _Objects_Put( &the_message_queue->Object );
+      *count = _CORE_message_queue_Flush(
+        &the_message_queue->message_queue,
+        &lock_context
+      );
       return RTEMS_SUCCESSFUL;
 
 #if defined(RTEMS_MULTIPROCESSING)
diff --git a/cpukit/rtems/src/msgqreceive.c b/cpukit/rtems/src/msgqreceive.c
index db09cfe547..2b9a4e742b 100644
--- a/cpukit/rtems/src/msgqreceive.c
+++ b/cpukit/rtems/src/msgqreceive.c
@@ -42,6 +42,7 @@ rtems_status_code rtems_message_queue_receive(
   Objects_Locations               location;
   bool                            wait;
   Thread_Control                 *executing;
+  ISR_lock_Context                lock_context;
 
   if ( !buffer )
     return RTEMS_INVALID_ADDRESS;
@@ -49,7 +50,11 @@ rtems_status_code rtems_message_queue_receive(
   if ( !size )
     return RTEMS_INVALID_ADDRESS;
 
-  the_message_queue = _Message_queue_Get( id, &location );
+  the_message_queue = _Message_queue_Get_interrupt_disable(
+    id,
+    &location,
+    &lock_context
+  );
   switch ( location ) {
 
     case OBJECTS_LOCAL:
@@ -66,9 +71,9 @@ rtems_status_code rtems_message_queue_receive(
         buffer,
         size,
         wait,
-        timeout
+        timeout,
+        &lock_context
       );
-      _Objects_Put( &the_message_queue->Object );
       return _Message_queue_Translate_core_message_queue_return_code(
         executing->Wait.return_code
       );
diff --git a/cpukit/rtems/src/msgqsend.c b/cpukit/rtems/src/msgqsend.c
index 34b7c29e7c..fb3979ed78 100644
--- a/cpukit/rtems/src/msgqsend.c
+++ b/cpukit/rtems/src/msgqsend.c
@@ -62,11 +62,16 @@ rtems_status_code rtems_message_queue_send(
   Message_queue_Control           *the_message_queue;
   Objects_Locations                location;
   CORE_message_queue_Status        status;
+  ISR_lock_Context                 lock_context;
 
   if ( !buffer )
     return RTEMS_INVALID_ADDRESS;
 
-  the_message_queue = _Message_queue_Get( id, &location );
+  the_message_queue = _Message_queue_Get_interrupt_disable(
+    id,
+    &location,
+    &lock_context
+  );
   switch ( location ) {
 
     case OBJECTS_LOCAL:
@@ -77,11 +82,10 @@ rtems_status_code rtems_message_queue_send(
         id,
         MESSAGE_QUEUE_MP_HANDLER,
         false,   /* sender does not block */
-        0        /* no timeout */
+        0,       /* no timeout */
+        &lock_context
       );
 
-      _Objects_Put( &the_message_queue->Object );
-
       /*
        *  Since this API does not allow for blocking sends, we can directly
        *  return the returned status.
diff --git a/cpukit/rtems/src/msgqurgent.c b/cpukit/rtems/src/msgqurgent.c
index 85a9d4f1b4..e6ae5efcf0 100644
--- a/cpukit/rtems/src/msgqurgent.c
+++ b/cpukit/rtems/src/msgqurgent.c
@@ -45,11 +45,16 @@ rtems_status_code rtems_message_queue_urgent(
   Message_queue_Control           *the_message_queue;
   Objects_Locations                location;
   CORE_message_queue_Status        status;
+  ISR_lock_Context                 lock_context;
 
   if ( !buffer )
     return RTEMS_INVALID_ADDRESS;
 
-  the_message_queue = _Message_queue_Get( id, &location );
+  the_message_queue = _Message_queue_Get_interrupt_disable(
+    id,
+    &location,
+    &lock_context
+  );
   switch ( location ) {
 
     case OBJECTS_LOCAL:
@@ -60,9 +65,9 @@ rtems_status_code rtems_message_queue_urgent(
         id,
         MESSAGE_QUEUE_MP_HANDLER,
         false,   /* sender does not block */
-        0        /* no timeout */
+        0,       /* no timeout */
+        &lock_context
       );
-      _Objects_Put( &the_message_queue->Object );
 
       /*
        *  Since this API does not allow for blocking sends, we can directly