score: Add thread priority change handler

Since the thread current priority change and thread queue requeue is
performed in one critical section it is possible to simplify the thread
queue requeue procedure.  Add a thread queue agnostic thread priority
change handler so that we are able to use alternative thread queue
implementations.

Update #2273.

1 files changed, 25 insertions, 42 deletions

diff --git a/cpukit/score/src/threadqenqueue.c b/cpukit/score/src/threadqenqueue.c
index 39353fe6d4..572d8403ff 100644
--- a/cpukit/score/src/threadqenqueue.c
+++ b/cpukit/score/src/threadqenqueue.c
@@ -73,6 +73,24 @@ static void _Thread_blocking_operation_Finalize(
 #endif
 }
 
+static void _Thread_queue_Requeue_priority(
+  Thread_Control   *the_thread,
+  Priority_Control  new_priority,
+  void             *context
+)
+{
+  Thread_queue_Control *tq = context;
+
+  _Thread_queue_Enter_critical_section( tq );
+  _RBTree_Extract( &tq->Queues.Priority, &the_thread->RBNode );
+  _RBTree_Insert(
+    &tq->Queues.Priority,
+    &the_thread->RBNode,
+    _Thread_queue_Compare_priority,
+    false
+  );
+}
+
 void _Thread_queue_Enqueue_with_handler(
   Thread_queue_Control         *the_thread_queue,
   Thread_Control               *the_thread,
@@ -127,6 +145,11 @@ void _Thread_queue_Enqueue_with_handler(
         &the_thread->Object.Node
       );
     } else { /* must be THREAD_QUEUE_DISCIPLINE_PRIORITY */
+      _Thread_Priority_set_change_handler(
+        the_thread,
+        _Thread_queue_Requeue_priority,
+        the_thread_queue
+      );
       _RBTree_Insert(
         &the_thread_queue->Queues.Priority,
         &the_thread->RBNode,
@@ -172,6 +195,7 @@ void _Thread_queue_Extract_with_return_code(
       &the_thread->Wait.queue->Queues.Priority,
       &the_thread->RBNode
     );
+    _Thread_Priority_restore_default_change_handler( the_thread );
   }
 
   the_thread->Wait.return_code = return_code;
@@ -221,6 +245,7 @@ Thread_Control *_Thread_queue_Dequeue(
     first = _RBTree_Get( &the_thread_queue->Queues.Priority, RBT_LEFT );
     if ( first ) {
       the_thread = THREAD_RBTREE_NODE_TO_THREAD( first );
+      _Thread_Priority_restore_default_change_handler( the_thread );
     }
   }
 
@@ -249,45 +274,3 @@ Thread_Control *_Thread_queue_Dequeue(
 
   return the_thread;
 }
-
-void _Thread_queue_Requeue(
-  Thread_queue_Control *the_thread_queue,
-  Thread_Control       *the_thread
-)
-{
-  /*
-   * Just in case the thread really wasn't blocked on a thread queue
-   * when we get here.
-   */
-  if ( !the_thread_queue )
-    return;
-
-  /*
-   * If queueing by FIFO, there is nothing to do. This only applies to
-   * priority blocking discipline.
-   */
-  if ( the_thread_queue->discipline == THREAD_QUEUE_DISCIPLINE_PRIORITY ) {
-    Thread_queue_Control *tq = the_thread_queue;
-    ISR_Level             level;
-
-    _ISR_Disable( level );
-    if ( _States_Is_waiting_on_thread_queue( the_thread->current_state ) ) {
-      _Thread_queue_Enter_critical_section( tq );
-
-      /* extract the thread */
-      _RBTree_Extract(
-        &the_thread->Wait.queue->Queues.Priority,
-        &the_thread->RBNode
-      );
-
-      /* enqueue the thread at the new priority */
-      _RBTree_Insert(
-        &the_thread_queue->Queues.Priority,
-        &the_thread->RBNode,
-        _Thread_queue_Compare_priority,
-        false
-      );
-    }
-    _ISR_Enable( level );
-  }
-}