score: Introduce thread queue surrender operation

This is an optimization for _Thread_queue_Surrender().  It helps to
encapsulate the priority boosting in the priority inheritance thread
queue operations.

cpukit/score/include/rtems/score/threadq.h

@@ -370,6 +370,23 @@ typedef void ( *Thread_queue_Extract_operation )(
   Thread_Control     *the_thread
 );
 
+/**
+ * @brief Thread queue surrender operation.
+ *
+ * This operation must dequeue and return the first thread on the queue.
+ *
+ * @param[in] queue The actual thread queue.
+ * @param[in] heads The thread queue heads.  It must not be NULL.
+ * @param[in] previous_owner The previous owner of the thread queue.
+ *
+ * @return The previous first thread on the queue.
+ */
+typedef Thread_Control *( *Thread_queue_Surrender_operation )(
+  Thread_queue_Queue *queue,
+  Thread_queue_Heads *heads,
+  Thread_Control     *previous_owner
+);
+
 /**
  * @brief Thread queue first operation.
  *
@@ -415,6 +432,11 @@ struct Thread_queue_Operations {
    */
   Thread_queue_Extract_operation extract;
 
+  /**
+   * @brief Thread queue surrender operation.
+   */
+  Thread_queue_Surrender_operation surrender;
+
   /**
    * @brief Thread queue first operation.
    */

cpukit/score/include/rtems/score/threadqimpl.h

@@ -946,31 +946,6 @@ RTEMS_INLINE_ROUTINE void _Thread_queue_Destroy(
 #endif
 }
 
-/**
- * @brief Boosts the priority of the thread if threads of another scheduler
- * instance are enqueued on the thread queue.
- *
- * The thread queue must use the priority waiting discipline.
- *
- * @param[in] queue The actual thread queue.
- * @param[in] the_thread The thread to boost the priority if necessary.
- */
-#if defined(RTEMS_SMP)
-void _Thread_queue_Boost_priority(
-  Thread_queue_Queue *queue,
-  Thread_Control     *the_thread
-);
-#else
-RTEMS_INLINE_ROUTINE void _Thread_queue_Boost_priority(
-  Thread_queue_Queue *queue,
-  Thread_Control     *the_thread
-)
-{
-  (void) queue;
-  (void) the_thread;
-}
-#endif
-
 #if defined(RTEMS_MULTIPROCESSING)
 void _Thread_queue_MP_callout_do_nothing(
   Thread_Control *the_proxy,

cpukit/score/src/threadqenqueue.c

@@ -596,7 +596,7 @@ void _Thread_queue_Surrender(
     Thread_Control *new_owner;
     bool            unblock;
 
-    new_owner = ( *operations->first )( heads );
+    new_owner = ( *operations->surrender )( queue, heads, previous_owner );
     queue->owner = new_owner;
 
 #if defined(RTEMS_MULTIPROCESSING)
@@ -604,10 +604,8 @@ void _Thread_queue_Surrender(
 #endif
     {
       ++new_owner->resource_count;
-      _Thread_queue_Boost_priority( queue, new_owner );
     }
 
-    ( *operations->extract )( queue, new_owner );
     unblock = _Thread_queue_Make_ready_again( new_owner );
 
     _Thread_queue_Unblock_critical(

cpukit/score/src/threadqops.c

@@ -71,12 +71,11 @@ static Thread_queue_Heads *_Thread_queue_Queue_enqueue(
 
 static void _Thread_queue_Queue_extract(
   Thread_queue_Queue *queue,
+  Thread_queue_Heads *heads,
   Thread_Control     *the_thread,
   void             ( *extract )( Thread_queue_Heads *, Thread_Control * )
 )
 {
-  Thread_queue_Heads *heads = queue->heads;
-
   _Assert( heads != NULL );
 
   the_thread->Wait.spare_heads = RTEMS_CONTAINER_OF(
@@ -142,6 +141,7 @@ static void _Thread_queue_FIFO_extract(
 {
   _Thread_queue_Queue_extract(
     queue,
+    queue->heads,
     the_thread,
     _Thread_queue_FIFO_do_extract
   );
@@ -160,6 +160,25 @@ static Thread_Control *_Thread_queue_FIFO_first(
   return THREAD_CHAIN_NODE_TO_THREAD( first );
 }
 
+static Thread_Control *_Thread_queue_FIFO_surrender(
+  Thread_queue_Queue *queue,
+  Thread_queue_Heads *heads,
+  Thread_Control     *previous_owner
+)
+{
+  Thread_Control *first;
+
+  first = _Thread_queue_FIFO_first( heads );
+  _Thread_queue_Queue_extract(
+    queue,
+    heads,
+    first,
+    _Thread_queue_FIFO_do_extract
+  );
+
+  return first;
+}
+
 static Thread_queue_Priority_queue *_Thread_queue_Priority_queue(
   Thread_queue_Heads   *heads,
   const Thread_Control *the_thread
@@ -296,6 +315,7 @@ static void _Thread_queue_Priority_extract(
 {
   _Thread_queue_Queue_extract(
     queue,
+    queue->heads,
     the_thread,
     _Thread_queue_Priority_do_extract
   );
@@ -322,6 +342,25 @@ static Thread_Control *_Thread_queue_Priority_first(
   return THREAD_RBTREE_NODE_TO_THREAD( first );
 }
 
+static Thread_Control *_Thread_queue_Priority_surrender(
+  Thread_queue_Queue *queue,
+  Thread_queue_Heads *heads,
+  Thread_Control     *previous_owner
+)
+{
+  Thread_Control *first;
+
+  first = _Thread_queue_Priority_first( heads );
+  _Thread_queue_Queue_extract(
+    queue,
+    heads,
+    first,
+    _Thread_queue_Priority_do_extract
+  );
+
+  return first;
+}
+
 static void _Thread_queue_Priority_inherit_enqueue(
   Thread_queue_Queue *queue,
   Thread_Control     *the_thread,
@@ -374,14 +413,12 @@ static void _Thread_queue_Priority_inherit_enqueue(
   }
 }
 
-#if defined(RTEMS_SMP)
-void _Thread_queue_Boost_priority(
-  Thread_queue_Queue *queue,
+static void _Thread_queue_Boost_priority(
+  Thread_queue_Heads *heads,
   Thread_Control     *the_thread
 )
 {
-  Thread_queue_Heads *heads = queue->heads;
-
+#if defined(RTEMS_SMP)
   if ( !_Chain_Has_only_one_node( &heads->Heads.Fifo ) ) {
     const Scheduler_Control *scheduler;
     Priority_Control         boost_priority;
@@ -394,8 +431,31 @@ void _Thread_queue_Boost_priority(
 
     _Scheduler_Thread_set_priority( the_thread, boost_priority, false );
   }
-}
+#else
+  (void) heads;
+  (void) the_thread;
 #endif
+}
+
+static Thread_Control *_Thread_queue_Priority_inherit_surrender(
+  Thread_queue_Queue *queue,
+  Thread_queue_Heads *heads,
+  Thread_Control     *previous_owner
+)
+{
+  Thread_Control *first;
+
+  first = _Thread_queue_Priority_first( heads );
+  _Thread_queue_Boost_priority( heads, first );
+  _Thread_queue_Queue_extract(
+    queue,
+    heads,
+    first,
+    _Thread_queue_Priority_do_extract
+  );
+
+  return first;
+}
 
 const Thread_queue_Operations _Thread_queue_Operations_default = {
   .priority_change = _Thread_queue_Do_nothing_priority_change,
@@ -411,6 +471,7 @@ const Thread_queue_Operations _Thread_queue_Operations_FIFO = {
   .priority_change = _Thread_queue_Do_nothing_priority_change,
   .enqueue = _Thread_queue_FIFO_enqueue,
   .extract = _Thread_queue_FIFO_extract,
+  .surrender = _Thread_queue_FIFO_surrender,
   .first = _Thread_queue_FIFO_first
 };
 
@@ -418,6 +479,7 @@ const Thread_queue_Operations _Thread_queue_Operations_priority = {
   .priority_change = _Thread_queue_Priority_priority_change,
   .enqueue = _Thread_queue_Priority_enqueue,
   .extract = _Thread_queue_Priority_extract,
+  .surrender = _Thread_queue_Priority_surrender,
   .first = _Thread_queue_Priority_first
 };
 
@@ -425,5 +487,6 @@ const Thread_queue_Operations _Thread_queue_Operations_priority_inherit = {
   .priority_change = _Thread_queue_Priority_priority_change,
   .enqueue = _Thread_queue_Priority_inherit_enqueue,
   .extract = _Thread_queue_Priority_extract,
+  .surrender = _Thread_queue_Priority_inherit_surrender,
   .first = _Thread_queue_Priority_first
 };