score: More thread queue operations

Move thread queue discipline specific operations into
Thread_queue_Operations.  Use a separate node in the thread control
block for the thread queue to make it independent of the scheduler data
structures.

Update #2273.

6 files changed, 160 insertions, 82 deletions

diff --git a/cpukit/score/src/thread.c b/cpukit/score/src/thread.c
index f4c53079d5..8a34ced684 100644
--- a/cpukit/score/src/thread.c
+++ b/cpukit/score/src/thread.c
@@ -28,7 +28,6 @@
   )
 
 THREAD_OFFSET_ASSERT( Object );
-THREAD_OFFSET_ASSERT( RBNode );
 THREAD_OFFSET_ASSERT( current_state );
 THREAD_OFFSET_ASSERT( current_priority );
 THREAD_OFFSET_ASSERT( real_priority );
diff --git a/cpukit/score/src/threadq.c b/cpukit/score/src/threadq.c
index 47c294e968..61832c19a2 100644
--- a/cpukit/score/src/threadq.c
+++ b/cpukit/score/src/threadq.c
@@ -19,9 +19,7 @@
 #endif
 
 #include <rtems/score/threadqimpl.h>
-#include <rtems/score/chainimpl.h>
 #include <rtems/score/rbtreeimpl.h>
-#include <rtems/score/scheduler.h>
 #include <rtems/score/threadimpl.h>
 
 RBTree_Compare_result _Thread_queue_Compare_priority(
@@ -51,15 +49,20 @@ void _Thread_queue_Initialize(
   uint32_t                      timeout_status
 )
 {
-  the_thread_queue->discipline     = the_discipline;
+  const Thread_queue_Operations *operations;
+
   the_thread_queue->timeout_status = timeout_status;
   the_thread_queue->sync_state     = THREAD_BLOCKING_OPERATION_SYNCHRONIZED;
 
   _ISR_lock_Initialize( &the_thread_queue->Lock, "Thread Queue" );
 
   if ( the_discipline == THREAD_QUEUE_DISCIPLINE_PRIORITY ) {
-    _RBTree_Initialize_empty( &the_thread_queue->Queues.Priority );
-  } else { /* must be THREAD_QUEUE_DISCIPLINE_FIFO */
-    _Chain_Initialize_empty( &the_thread_queue->Queues.Fifo );
+    operations = &_Thread_queue_Operations_priority;
+  } else {
+    _Assert( the_discipline == THREAD_QUEUE_DISCIPLINE_FIFO );
+    operations = &_Thread_queue_Operations_FIFO;
   }
+
+  the_thread_queue->operations = operations;
+  ( *operations->initialize )( the_thread_queue );
 }
diff --git a/cpukit/score/src/threadqenqueue.c b/cpukit/score/src/threadqenqueue.c
index 6cc731e282..be08ffcbf1 100644
--- a/cpukit/score/src/threadqenqueue.c
+++ b/cpukit/score/src/threadqenqueue.c
@@ -20,7 +20,6 @@
 
 #include <rtems/score/threadqimpl.h>
 #include <rtems/score/assert.h>
-#include <rtems/score/rbtreeimpl.h>
 #include <rtems/score/threadimpl.h>
 #include <rtems/score/watchdogimpl.h>
 
@@ -47,6 +46,7 @@ static void _Thread_blocking_operation_Finalize(
    * The thread is not waiting on anything after this completes.
    */
   _Thread_Wait_set_queue( the_thread, NULL );
+  _Thread_Wait_restore_default_operations( the_thread );
 
   _Thread_Lock_restore_default( the_thread );
 
@@ -127,28 +127,14 @@ void _Thread_queue_Enqueue_critical(
   the_thread_queue->sync_state = THREAD_BLOCKING_OPERATION_SYNCHRONIZED;
 
   if ( sync_state == THREAD_BLOCKING_OPERATION_NOTHING_HAPPENED ) {
-    /*
-     * Invoke the discipline specific enqueue method.
-     */
-    if ( the_thread_queue->discipline == THREAD_QUEUE_DISCIPLINE_FIFO ) {
-      _Chain_Append_unprotected(
-        &the_thread_queue->Queues.Fifo,
-        &the_thread->Object.Node
-      );
-    } else { /* must be THREAD_QUEUE_DISCIPLINE_PRIORITY */
-      _Thread_Wait_set_operations(
-        the_thread,
-        &_Thread_queue_Operations_priority
-      );
-      _RBTree_Insert(
-        &the_thread_queue->Queues.Priority,
-        &the_thread->RBNode,
-        _Thread_queue_Compare_priority,
-        false
-      );
-    }
+    const Thread_queue_Operations *operations;
 
     the_thread_queue->sync_state = THREAD_BLOCKING_OPERATION_SYNCHRONIZED;
+
+    operations = the_thread_queue->operations;
+    _Thread_Wait_set_operations( the_thread, operations );
+    ( *operations->enqueue )( the_thread_queue, the_thread );
+
     _Thread_queue_Release( the_thread_queue, lock_context );
   } else {
     /* Cancel a blocking operation due to ISR */
@@ -181,15 +167,7 @@ void _Thread_queue_Extract_with_return_code(
 
   _SMP_Assert( lock == &the_thread_queue->Lock );
 
-  if ( the_thread_queue->discipline == THREAD_QUEUE_DISCIPLINE_FIFO ) {
-    _Chain_Extract_unprotected( &the_thread->Object.Node );
-  } else { /* must be THREAD_QUEUE_DISCIPLINE_PRIORITY */
-    _RBTree_Extract(
-      &the_thread->Wait.queue->Queues.Priority,
-      &the_thread->RBNode
-    );
-    _Thread_Wait_restore_default_operations( the_thread );
-  }
+  ( *the_thread_queue->operations->extract )( the_thread_queue, the_thread );
 
   the_thread->Wait.return_code = return_code;
 
@@ -217,27 +195,9 @@ Thread_Control *_Thread_queue_Dequeue(
   ISR_lock_Context                  lock_context;
   Thread_blocking_operation_States  sync_state;
 
-  the_thread = NULL;
   _Thread_queue_Acquire( the_thread_queue, &lock_context );
 
-  /*
-   * Invoke the discipline specific dequeue method.
-   */
-  if ( the_thread_queue->discipline == THREAD_QUEUE_DISCIPLINE_FIFO ) {
-    if ( !_Chain_Is_empty( &the_thread_queue->Queues.Fifo ) ) {
-      the_thread = (Thread_Control *)
-       _Chain_Get_first_unprotected( &the_thread_queue->Queues.Fifo );
-    }
-  } else { /* must be THREAD_QUEUE_DISCIPLINE_PRIORITY */
-    RBTree_Node    *first;
-
-    first = _RBTree_Get( &the_thread_queue->Queues.Priority, RBT_LEFT );
-    if ( first ) {
-      the_thread = THREAD_RBTREE_NODE_TO_THREAD( first );
-      _Thread_Wait_restore_default_operations( the_thread );
-    }
-  }
-
+  the_thread = ( *the_thread_queue->operations->dequeue )( the_thread_queue );
   if ( the_thread == NULL ) {
     /*
      * We did not find a thread to unblock in the queue.  Maybe the executing
diff --git a/cpukit/score/src/threadqfirst.c b/cpukit/score/src/threadqfirst.c
index f43b9abbd0..553b28bf62 100644
--- a/cpukit/score/src/threadqfirst.c
+++ b/cpukit/score/src/threadqfirst.c
@@ -19,29 +19,12 @@
 #endif
 
 #include <rtems/score/threadqimpl.h>
-#include <rtems/score/chainimpl.h>
-#include <rtems/score/threadimpl.h>
 
 Thread_Control *_Thread_queue_First_locked(
   Thread_queue_Control *the_thread_queue
 )
 {
-  Thread_Control *thread;
-
-  thread = NULL;
-
-  if ( the_thread_queue->discipline == THREAD_QUEUE_DISCIPLINE_FIFO ) {
-    if ( !_Chain_Is_empty( &the_thread_queue->Queues.Fifo ) )
-      thread = (Thread_Control *) _Chain_First(&the_thread_queue->Queues.Fifo);
-  } else { /* must be THREAD_QUEUE_DISCIPLINE_PRIORITY */
-    RBTree_Node *first;
-
-    first = _RBTree_First( &the_thread_queue->Queues.Priority, RBT_LEFT );
-    if ( first )
-      thread = THREAD_RBTREE_NODE_TO_THREAD( first );
-  }
-
-  return thread;
+  return ( *the_thread_queue->operations->first )( the_thread_queue );
 }
 
 Thread_Control *_Thread_queue_First(
diff --git a/cpukit/score/src/threadqops.c b/cpukit/score/src/threadqops.c
index 561480130a..9958ed667c 100644
--- a/cpukit/score/src/threadqops.c
+++ b/cpukit/score/src/threadqops.c
@@ -17,40 +17,167 @@
 #endif
 
 #include <rtems/score/threadimpl.h>
+#include <rtems/score/chainimpl.h>
 #include <rtems/score/rbtreeimpl.h>
 
 static void _Thread_queue_Do_nothing_priority_change(
   Thread_Control       *the_thread,
   Priority_Control      new_priority,
-  Thread_queue_Control *queue
+  Thread_queue_Control *the_thread_queue
 )
 {
   /* Do nothing */
 }
 
+static void _Thread_queue_Do_nothing_extract(
+  Thread_queue_Control *the_thread_queue,
+  Thread_Control       *the_thread
+)
+{
+  /* Do nothing */
+}
+
+static void _Thread_queue_FIFO_initialize(
+  Thread_queue_Control *the_thread_queue
+)
+{
+  _Chain_Initialize_empty( &the_thread_queue->Queues.Fifo );
+}
+
+static void _Thread_queue_FIFO_enqueue(
+  Thread_queue_Control *the_thread_queue,
+  Thread_Control       *the_thread
+)
+{
+  _Chain_Append_unprotected(
+    &the_thread_queue->Queues.Fifo,
+    &the_thread->Wait.Node.Chain
+  );
+}
+
+static Thread_Control *_Thread_queue_FIFO_dequeue(
+  Thread_queue_Control *the_thread_queue
+)
+{
+  Chain_Control *fifo = &the_thread_queue->Queues.Fifo;
+
+  return _Chain_Is_empty( fifo ) ?
+    NULL : THREAD_CHAIN_NODE_TO_THREAD( _Chain_Get_first_unprotected( fifo ) );
+}
+
+static void _Thread_queue_FIFO_extract(
+  Thread_queue_Control *the_thread_queue,
+  Thread_Control       *the_thread
+)
+{
+  _Chain_Extract_unprotected( &the_thread->Wait.Node.Chain );
+}
+
+static Thread_Control *_Thread_queue_FIFO_first(
+  Thread_queue_Control *the_thread_queue
+)
+{
+  Chain_Control *fifo = &the_thread_queue->Queues.Fifo;
+
+  return _Chain_Is_empty( fifo ) ?
+    NULL : THREAD_CHAIN_NODE_TO_THREAD( _Chain_First( fifo ) );
+}
+
 static void _Thread_queue_Priority_priority_change(
   Thread_Control       *the_thread,
   Priority_Control      new_priority,
-  Thread_queue_Control *queue
+  Thread_queue_Control *the_thread_queue
+)
+{
+  _RBTree_Extract(
+    &the_thread_queue->Queues.Priority,
+    &the_thread->Wait.Node.RBTree
+  );
+  _RBTree_Insert(
+    &the_thread_queue->Queues.Priority,
+    &the_thread->Wait.Node.RBTree,
+    _Thread_queue_Compare_priority,
+    false
+  );
+}
+
+static void _Thread_queue_Priority_initialize(
+  Thread_queue_Control *the_thread_queue
+)
+{
+  _RBTree_Initialize_empty( &the_thread_queue->Queues.Priority );
+}
+
+static void _Thread_queue_Priority_enqueue(
+  Thread_queue_Control *the_thread_queue,
+  Thread_Control       *the_thread
 )
 {
-  _RBTree_Extract( &queue->Queues.Priority, &the_thread->RBNode );
   _RBTree_Insert(
-    &queue->Queues.Priority,
-    &the_thread->RBNode,
+    &the_thread_queue->Queues.Priority,
+    &the_thread->Wait.Node.RBTree,
     _Thread_queue_Compare_priority,
     false
   );
 }
 
+static Thread_Control *_Thread_queue_Priority_dequeue(
+  Thread_queue_Control *the_thread_queue
+)
+{
+  RBTree_Node *first;
+
+  first = _RBTree_Get( &the_thread_queue->Queues.Priority, RBT_LEFT );
+
+  return first != NULL ? THREAD_RBTREE_NODE_TO_THREAD( first ) : NULL;
+}
+
+static void _Thread_queue_Priority_extract(
+  Thread_queue_Control *the_thread_queue,
+  Thread_Control       *the_thread
+)
+{
+  _RBTree_Extract(
+    &the_thread_queue->Queues.Priority,
+    &the_thread->Wait.Node.RBTree
+  );
+}
+
+static Thread_Control *_Thread_queue_Priority_first(
+  Thread_queue_Control *the_thread_queue
+)
+{
+  RBTree_Node *first;
+
+  first = _RBTree_First( &the_thread_queue->Queues.Priority, RBT_LEFT );
+
+  return first != NULL ? THREAD_RBTREE_NODE_TO_THREAD( first ) : NULL;
+}
+
 const Thread_queue_Operations _Thread_queue_Operations_default = {
-  .priority_change = _Thread_queue_Do_nothing_priority_change
+  .priority_change = _Thread_queue_Do_nothing_priority_change,
+  .extract = _Thread_queue_Do_nothing_extract
+  /*
+   * The default operations are only used in _Thread_Change_priority() and
+   * _Thread_Timeout() and don't have a thread queue associated with them, so
+   * the enqueue and first operations are superfluous.
+   */
 };
 
 const Thread_queue_Operations _Thread_queue_Operations_FIFO = {
-  .priority_change = _Thread_queue_Do_nothing_priority_change
+  .priority_change = _Thread_queue_Do_nothing_priority_change,
+  .initialize = _Thread_queue_FIFO_initialize,
+  .enqueue = _Thread_queue_FIFO_enqueue,
+  .dequeue = _Thread_queue_FIFO_dequeue,
+  .extract = _Thread_queue_FIFO_extract,
+  .first = _Thread_queue_FIFO_first
 };
 
 const Thread_queue_Operations _Thread_queue_Operations_priority = {
-  .priority_change = _Thread_queue_Priority_priority_change
+  .priority_change = _Thread_queue_Priority_priority_change,
+  .initialize = _Thread_queue_Priority_initialize,
+  .enqueue = _Thread_queue_Priority_enqueue,
+  .dequeue = _Thread_queue_Priority_dequeue,
+  .extract = _Thread_queue_Priority_extract,
+  .first = _Thread_queue_Priority_first
 };
diff --git a/cpukit/score/src/threadtimeout.c b/cpukit/score/src/threadtimeout.c
index b6ce2d7362..300beb5219 100644
--- a/cpukit/score/src/threadtimeout.c
+++ b/cpukit/score/src/threadtimeout.c
@@ -24,6 +24,12 @@
 static void _Thread_Do_timeout( Thread_Control *the_thread )
 {
   the_thread->Wait.return_code = the_thread->Wait.timeout_code;
+  ( *the_thread->Wait.operations->extract )(
+    the_thread->Wait.queue,
+    the_thread
+  );
+  _Thread_Wait_set_queue( the_thread, NULL );
+  _Thread_Wait_restore_default_operations( the_thread );
   _Thread_Lock_restore_default( the_thread );
 }