score: Optimize scheduler priority updates

Thread priority changes may append or prepend the thread to its priority
group on the scheduler ready queue.  Previously, a separate priority
value and a prepend-it flag in the scheduler node were used to propagate
a priority change to the scheduler.

Now, use an append-it bit in the priority control and reduce the plain
priority value to 63 bits.

This change leads to a significant code size reduction (about 25%) of
the SMP schedulers.  The negligible increase of the standard priority
scheduler is due to some additional shift operations
(SCHEDULER_PRIORITY_MAP() and SCHEDULER_PRIORITY_UNMAP()).

Before:

   text filename
    136 sparc-rtems5/c/erc32/cpukit/score/src/libscore_a-schedulersimpleblock.o
    464 sparc-rtems5/c/erc32/cpukit/score/src/libscore_a-schedulersimplechangepriority.o
     24 sparc-rtems5/c/erc32/cpukit/score/src/libscore_a-schedulersimple.o
    108 sparc-rtems5/c/erc32/cpukit/score/src/libscore_a-schedulersimpleschedule.o
    292 sparc-rtems5/c/erc32/cpukit/score/src/libscore_a-schedulersimpleunblock.o
    264 sparc-rtems5/c/erc32/cpukit/score/src/libscore_a-schedulersimpleyield.o

   text filename
    280 sparc-rtems5/c/erc32/cpukit/score/src/libscore_a-schedulerpriorityblock.o
    488 sparc-rtems5/c/erc32/cpukit/score/src/libscore_a-schedulerprioritychangepriority.o
    200 sparc-rtems5/c/erc32/cpukit/score/src/libscore_a-schedulerpriority.o
    164 sparc-rtems5/c/erc32/cpukit/score/src/libscore_a-schedulerpriorityschedule.o
    328 sparc-rtems5/c/erc32/cpukit/score/src/libscore_a-schedulerpriorityunblock.o
    200 sparc-rtems5/c/erc32/cpukit/score/src/libscore_a-schedulerpriorityyield.o

   text filename
  24112 arm-rtems5/c/imx7/cpukit/score/src/libscore_a-scheduleredfsmp.o

   text filename
  37204 sparc-rtems5/c/gr740/cpukit/score/src/libscore_a-scheduleredfsmp.o

   text filename
  42236 powerpc-rtems5/c/qoriq_e6500_32/cpukit/score/src/libscore_a-scheduleredfsmp.o

After:

   text filename
    136 sparc-rtems5/c/erc32/cpukit/score/src/libscore_a-schedulersimpleblock.o
    272 sparc-rtems5/c/erc32/cpukit/score/src/libscore_a-schedulersimplechangepriority.o
     24 sparc-rtems5/c/erc32/cpukit/score/src/libscore_a-schedulersimple.o
    108 sparc-rtems5/c/erc32/cpukit/score/src/libscore_a-schedulersimpleschedule.o
    292 sparc-rtems5/c/erc32/cpukit/score/src/libscore_a-schedulersimpleunblock.o
    264 sparc-rtems5/c/erc32/cpukit/score/src/libscore_a-schedulersimpleyield.o

   text filename
    280 sparc-rtems5/c/erc32/cpukit/score/src/libscore_a-schedulerpriorityblock.o
    488 sparc-rtems5/c/erc32/cpukit/score/src/libscore_a-schedulerprioritychangepriority.o
    208 sparc-rtems5/c/erc32/cpukit/score/src/libscore_a-schedulerpriority.o
    164 sparc-rtems5/c/erc32/cpukit/score/src/libscore_a-schedulerpriorityschedule.o
    332 sparc-rtems5/c/erc32/cpukit/score/src/libscore_a-schedulerpriorityunblock.o
    200 sparc-rtems5/c/erc32/cpukit/score/src/libscore_a-schedulerpriorityyield.o

   text filename
  18860 arm-rtems5/c/imx7/cpukit/score/src/libscore_a-scheduleredfsmp.o

   text filename
  28520 sparc-rtems5/c/gr740/cpukit/score/src/libscore_a-scheduleredfsmp.o

   text filename
  32664 powerpc-rtems5/c/qoriq_e6500_32/cpukit/score/src/libscore_a-scheduleredfsmp.o

16 files changed, 276 insertions, 628 deletions

diff --git a/cpukit/score/src/schedulercbsunblock.c b/cpukit/score/src/schedulercbsunblock.c
index 403435eeb1..9b7a0ca424 100644
--- a/cpukit/score/src/schedulercbsunblock.c
+++ b/cpukit/score/src/schedulercbsunblock.c
@@ -34,12 +34,11 @@ void _Scheduler_CBS_Unblock(
   Scheduler_CBS_Node   *the_node;
   Scheduler_CBS_Server *serv_info;
   Priority_Control      priority;
-  bool                  prepend_it;
 
   the_node = _Scheduler_CBS_Node_downcast( node );
   serv_info = the_node->cbs_server;
-  priority = _Scheduler_Node_get_priority( &the_node->Base.Base, &prepend_it );
-  (void) prepend_it;
+  priority = _Scheduler_Node_get_priority( &the_node->Base.Base );
+  priority = SCHEDULER_PRIORITY_PURIFY( priority );
 
   /*
    * Late unblock rule for deadline-driven tasks. The remaining time to
diff --git a/cpukit/score/src/schedulerdefaultmappriority.c b/cpukit/score/src/schedulerdefaultmappriority.c
index 37a600011e..228549f20d 100644
--- a/cpukit/score/src/schedulerdefaultmappriority.c
+++ b/cpukit/score/src/schedulerdefaultmappriority.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016 embedded brains GmbH
+ * Copyright (c) 2016, 2017 embedded brains GmbH
  *
  * The license and distribution terms for this file may be
  * found in the file LICENSE in this distribution or at
@@ -10,12 +10,20 @@
 #include "config.h"
 #endif
 
-#include <rtems/score/scheduler.h>
+#include <rtems/score/schedulerimpl.h>
 
 Priority_Control _Scheduler_default_Map_priority(
   const Scheduler_Control *scheduler,
   Priority_Control         priority
 )
 {
-  return priority;
+  return SCHEDULER_PRIORITY_MAP( priority );
+}
+
+Priority_Control _Scheduler_default_Unmap_priority(
+  const Scheduler_Control *scheduler,
+  Priority_Control         priority
+)
+{
+  return SCHEDULER_PRIORITY_UNMAP( priority );
 }
diff --git a/cpukit/score/src/scheduleredfchangepriority.c b/cpukit/score/src/scheduleredfchangepriority.c
index 23382973cc..d3d1f94cbf 100644
--- a/cpukit/score/src/scheduleredfchangepriority.c
+++ b/cpukit/score/src/scheduleredfchangepriority.c
@@ -29,7 +29,7 @@ void _Scheduler_EDF_Update_priority(
   Scheduler_EDF_Context *context;
   Scheduler_EDF_Node    *the_node;
   Priority_Control       priority;
-  bool                   prepend_it;
+  Priority_Control       insert_priority;
 
   if ( !_Thread_Is_ready( the_thread ) ) {
     /* Nothing to do */
@@ -37,7 +37,8 @@ void _Scheduler_EDF_Update_priority(
   }
 
   the_node = _Scheduler_EDF_Node_downcast( node );
-  priority = _Scheduler_Node_get_priority( &the_node->Base, &prepend_it );
+  insert_priority = _Scheduler_Node_get_priority( &the_node->Base );
+  priority = SCHEDULER_PRIORITY_PURIFY( insert_priority );
 
   if ( priority == the_node->priority ) {
     /* Nothing to do */
@@ -48,12 +49,6 @@ void _Scheduler_EDF_Update_priority(
   context = _Scheduler_EDF_Get_context( scheduler );
 
   _Scheduler_EDF_Extract( context, the_node );
-
-  if ( prepend_it ) {
-    _Scheduler_EDF_Enqueue_first( context, the_node, priority );
-  } else {
-    _Scheduler_EDF_Enqueue( context, the_node, priority );
-  }
-
+  _Scheduler_EDF_Enqueue( context, the_node, insert_priority );
   _Scheduler_EDF_Schedule_body( scheduler, the_thread, false );
 }
diff --git a/cpukit/score/src/scheduleredfreleasejob.c b/cpukit/score/src/scheduleredfreleasejob.c
index 068a0db7a3..d7865ff5fb 100644
--- a/cpukit/score/src/scheduleredfreleasejob.c
+++ b/cpukit/score/src/scheduleredfreleasejob.c
@@ -25,7 +25,7 @@ Priority_Control _Scheduler_EDF_Map_priority(
   Priority_Control         priority
 )
 {
-  return SCHEDULER_EDF_PRIO_MSB | priority;
+  return SCHEDULER_EDF_PRIO_MSB | SCHEDULER_PRIORITY_MAP( priority );
 }
 
 Priority_Control _Scheduler_EDF_Unmap_priority(
@@ -33,7 +33,7 @@ Priority_Control _Scheduler_EDF_Unmap_priority(
   Priority_Control         priority
 )
 {
-  return priority & ~SCHEDULER_EDF_PRIO_MSB;
+  return SCHEDULER_PRIORITY_UNMAP( priority & ~SCHEDULER_EDF_PRIO_MSB );
 }
 
 void _Scheduler_EDF_Release_job(
@@ -48,7 +48,16 @@ void _Scheduler_EDF_Release_job(
 
   _Thread_Wait_acquire_critical( the_thread, queue_context );
 
-  _Priority_Node_set_priority( priority_node, deadline );
+  /*
+   * There is no integer overflow problem here due to the
+   * SCHEDULER_PRIORITY_MAP().  The deadline is in clock ticks.  With the
+   * minimum clock tick interval of 1us, the uptime is limited to about 146235
+   * years.
+   */
+  _Priority_Node_set_priority(
+    priority_node,
+    SCHEDULER_PRIORITY_MAP( deadline )
+  );
 
   if ( _Priority_Node_is_active( priority_node ) ) {
     _Thread_Priority_changed(
diff --git a/cpukit/score/src/scheduleredfsmp.c b/cpukit/score/src/scheduleredfsmp.c
index badee44e2e..102a33d4f7 100644
--- a/cpukit/score/src/scheduleredfsmp.c
+++ b/cpukit/score/src/scheduleredfsmp.c
@@ -39,26 +39,7 @@ _Scheduler_EDF_SMP_Node_downcast( Scheduler_Node *node )
   return (Scheduler_EDF_SMP_Node *) node;
 }
 
-static inline bool _Scheduler_EDF_SMP_Less(
-  const void        *left,
-  const RBTree_Node *right
-)
-{
-  const Priority_Control   *the_left;
-  const Scheduler_SMP_Node *the_right;
-  Priority_Control          prio_left;
-  Priority_Control          prio_right;
-
-  the_left = left;
-  the_right = RTEMS_CONTAINER_OF( right, Scheduler_SMP_Node, Base.Node.RBTree );
-
-  prio_left = *the_left;
-  prio_right = the_right->priority;
-
-  return prio_left < prio_right;
-}
-
-static inline bool _Scheduler_EDF_SMP_Less_or_equal(
+static inline bool _Scheduler_EDF_SMP_Priority_less_equal(
   const void        *left,
   const RBTree_Node *right
 )
@@ -254,20 +235,21 @@ static inline Scheduler_Node *_Scheduler_EDF_SMP_Get_lowest_scheduled(
 static inline void _Scheduler_EDF_SMP_Insert_ready(
   Scheduler_Context *context,
   Scheduler_Node    *node_base,
-  int                generation_index,
-  bool            ( *less )( const void *, const RBTree_Node * )
+  Priority_Control   insert_priority
 )
 {
   Scheduler_EDF_SMP_Context     *self;
   Scheduler_EDF_SMP_Node        *node;
   uint32_t                       rqi;
   Scheduler_EDF_SMP_Ready_queue *ready_queue;
+  int                            generation_index;
   int                            increment;
   int64_t                        generation;
 
   self = _Scheduler_EDF_SMP_Get_self( context );
   node = _Scheduler_EDF_SMP_Node_downcast( node_base );
   rqi = node->ready_queue_index;
+  generation_index = SCHEDULER_PRIORITY_IS_APPEND( insert_priority );
   increment = ( generation_index << 1 ) - 1;
   ready_queue = &self->Ready[ rqi ];
 
@@ -279,8 +261,8 @@ static inline void _Scheduler_EDF_SMP_Insert_ready(
   _RBTree_Insert_inline(
     &ready_queue->Queue,
     &node->Base.Base.Node.RBTree,
-    &node->Base.priority,
-    less
+    &insert_priority,
+    _Scheduler_EDF_SMP_Priority_less_equal
   );
 
   if ( rqi != 0 && _Chain_Is_node_off_chain( &ready_queue->Node ) ) {
@@ -327,12 +309,14 @@ static inline void _Scheduler_EDF_SMP_Move_from_scheduled_to_ready(
   Scheduler_Node    *scheduled_to_ready
 )
 {
+  Priority_Control insert_priority;
+
   _Chain_Extract_unprotected( &scheduled_to_ready->Node.Chain );
+  insert_priority = _Scheduler_SMP_Node_priority( scheduled_to_ready );
   _Scheduler_EDF_SMP_Insert_ready(
     context,
     scheduled_to_ready,
-    1,
-    _Scheduler_EDF_SMP_Less
+    insert_priority
   );
 }
 
@@ -341,33 +325,15 @@ static inline void _Scheduler_EDF_SMP_Move_from_ready_to_scheduled(
   Scheduler_Node    *ready_to_scheduled
 )
 {
-  _Scheduler_EDF_SMP_Extract_from_ready( context, ready_to_scheduled );
-  _Scheduler_SMP_Insert_scheduled_fifo( context, ready_to_scheduled );
-}
+  Priority_Control insert_priority;
 
-static inline void _Scheduler_EDF_SMP_Insert_ready_lifo(
-  Scheduler_Context *context,
-  Scheduler_Node    *node_to_insert
-)
-{
-  _Scheduler_EDF_SMP_Insert_ready(
-    context,
-    node_to_insert,
-    0,
-    _Scheduler_EDF_SMP_Less_or_equal
-  );
-}
-
-static inline void _Scheduler_EDF_SMP_Insert_ready_fifo(
-  Scheduler_Context *context,
-  Scheduler_Node    *node_to_insert
-)
-{
-  _Scheduler_EDF_SMP_Insert_ready(
+  _Scheduler_EDF_SMP_Extract_from_ready( context, ready_to_scheduled );
+  insert_priority = _Scheduler_SMP_Node_priority( ready_to_scheduled );
+  insert_priority = SCHEDULER_PRIORITY_APPEND( insert_priority );
+  _Scheduler_SMP_Insert_scheduled(
     context,
-    node_to_insert,
-    1,
-    _Scheduler_EDF_SMP_Less
+    ready_to_scheduled,
+    insert_priority
   );
 }
 
@@ -444,103 +410,45 @@ void _Scheduler_EDF_SMP_Block(
   );
 }
 
-static inline bool _Scheduler_EDF_SMP_Enqueue_ordered(
-  Scheduler_Context    *context,
-  Scheduler_Node       *node,
-  Chain_Node_order      order,
-  Scheduler_SMP_Insert  insert_ready,
-  Scheduler_SMP_Insert  insert_scheduled
+static inline bool _Scheduler_EDF_SMP_Enqueue(
+  Scheduler_Context *context,
+  Scheduler_Node    *node,
+  Priority_Control   insert_priority
 )
 {
-  return _Scheduler_SMP_Enqueue_ordered(
+  return _Scheduler_SMP_Enqueue(
     context,
     node,
-    order,
-    insert_ready,
-    insert_scheduled,
+    insert_priority,
+    _Scheduler_SMP_Priority_less_equal,
+    _Scheduler_EDF_SMP_Insert_ready,
+    _Scheduler_SMP_Insert_scheduled,
     _Scheduler_EDF_SMP_Move_from_scheduled_to_ready,
     _Scheduler_EDF_SMP_Get_lowest_scheduled,
     _Scheduler_EDF_SMP_Allocate_processor
   );
 }
 
-static inline bool _Scheduler_EDF_SMP_Enqueue_lifo(
+static inline bool _Scheduler_EDF_SMP_Enqueue_scheduled(
   Scheduler_Context *context,
-  Scheduler_Node    *node
-)
-{
-  return _Scheduler_EDF_SMP_Enqueue_ordered(
-    context,
-    node,
-    _Scheduler_SMP_Insert_priority_lifo_order,
-    _Scheduler_EDF_SMP_Insert_ready_lifo,
-    _Scheduler_SMP_Insert_scheduled_lifo
-  );
-}
-
-static inline bool _Scheduler_EDF_SMP_Enqueue_fifo(
-  Scheduler_Context *context,
-  Scheduler_Node    *node
-)
-{
-  return _Scheduler_EDF_SMP_Enqueue_ordered(
-    context,
-    node,
-    _Scheduler_SMP_Insert_priority_fifo_order,
-    _Scheduler_EDF_SMP_Insert_ready_fifo,
-    _Scheduler_SMP_Insert_scheduled_fifo
-  );
-}
-
-static inline bool _Scheduler_EDF_SMP_Enqueue_scheduled_ordered(
-  Scheduler_Context *context,
-  Scheduler_Node *node,
-  Chain_Node_order order,
-  Scheduler_SMP_Insert insert_ready,
-  Scheduler_SMP_Insert insert_scheduled
+  Scheduler_Node    *node,
+  Priority_Control   insert_priority
 )
 {
-  return _Scheduler_SMP_Enqueue_scheduled_ordered(
+  return _Scheduler_SMP_Enqueue_scheduled(
     context,
     node,
-    order,
+    insert_priority,
+    _Scheduler_SMP_Priority_less_equal,
     _Scheduler_EDF_SMP_Extract_from_ready,
     _Scheduler_EDF_SMP_Get_highest_ready,
-    insert_ready,
-    insert_scheduled,
+    _Scheduler_EDF_SMP_Insert_ready,
+    _Scheduler_SMP_Insert_scheduled,
     _Scheduler_EDF_SMP_Move_from_ready_to_scheduled,
     _Scheduler_EDF_SMP_Allocate_processor
   );
 }
 
-static inline bool _Scheduler_EDF_SMP_Enqueue_scheduled_lifo(
-  Scheduler_Context *context,
-  Scheduler_Node *node
-)
-{
-  return _Scheduler_EDF_SMP_Enqueue_scheduled_ordered(
-    context,
-    node,
-    _Scheduler_SMP_Insert_priority_lifo_order,
-    _Scheduler_EDF_SMP_Insert_ready_lifo,
-    _Scheduler_SMP_Insert_scheduled_lifo
-  );
-}
-
-static inline bool _Scheduler_EDF_SMP_Enqueue_scheduled_fifo(
-  Scheduler_Context *context,
-  Scheduler_Node *node
-)
-{
-  return _Scheduler_EDF_SMP_Enqueue_scheduled_ordered(
-    context,
-    node,
-    _Scheduler_SMP_Insert_priority_fifo_order,
-    _Scheduler_EDF_SMP_Insert_ready_fifo,
-    _Scheduler_SMP_Insert_scheduled_fifo
-  );
-}
-
 void _Scheduler_EDF_SMP_Unblock(
   const Scheduler_Control *scheduler,
   Thread_Control          *thread,
@@ -554,7 +462,7 @@ void _Scheduler_EDF_SMP_Unblock(
     thread,
     node,
     _Scheduler_EDF_SMP_Do_update,
-    _Scheduler_EDF_SMP_Enqueue_fifo
+    _Scheduler_EDF_SMP_Enqueue
   );
 }
 
@@ -568,9 +476,9 @@ static inline bool _Scheduler_EDF_SMP_Do_ask_for_help(
     context,
     the_thread,
     node,
-    _Scheduler_SMP_Insert_priority_lifo_order,
-    _Scheduler_EDF_SMP_Insert_ready_lifo,
-    _Scheduler_SMP_Insert_scheduled_lifo,
+    _Scheduler_SMP_Priority_less_equal,
+    _Scheduler_EDF_SMP_Insert_ready,
+    _Scheduler_SMP_Insert_scheduled,
     _Scheduler_EDF_SMP_Move_from_scheduled_to_ready,
     _Scheduler_EDF_SMP_Get_lowest_scheduled,
     _Scheduler_EDF_SMP_Allocate_processor
@@ -591,10 +499,8 @@ void _Scheduler_EDF_SMP_Update_priority(
     node,
     _Scheduler_EDF_SMP_Extract_from_ready,
     _Scheduler_EDF_SMP_Do_update,
-    _Scheduler_EDF_SMP_Enqueue_fifo,
-    _Scheduler_EDF_SMP_Enqueue_lifo,
-    _Scheduler_EDF_SMP_Enqueue_scheduled_fifo,
-    _Scheduler_EDF_SMP_Enqueue_scheduled_lifo,
+    _Scheduler_EDF_SMP_Enqueue,
+    _Scheduler_EDF_SMP_Enqueue_scheduled,
     _Scheduler_EDF_SMP_Do_ask_for_help
   );
 }
@@ -672,7 +578,7 @@ void _Scheduler_EDF_SMP_Add_processor(
     context,
     idle,
     _Scheduler_EDF_SMP_Has_ready,
-    _Scheduler_EDF_SMP_Enqueue_scheduled_fifo,
+    _Scheduler_EDF_SMP_Enqueue_scheduled,
     _Scheduler_EDF_SMP_Register_idle
   );
 }
@@ -688,7 +594,7 @@ Thread_Control *_Scheduler_EDF_SMP_Remove_processor(
     context,
     cpu,
     _Scheduler_EDF_SMP_Extract_from_ready,
-    _Scheduler_EDF_SMP_Enqueue_fifo
+    _Scheduler_EDF_SMP_Enqueue
   );
 }
 
@@ -705,8 +611,8 @@ void _Scheduler_EDF_SMP_Yield(
     thread,
     node,
     _Scheduler_EDF_SMP_Extract_from_ready,
-    _Scheduler_EDF_SMP_Enqueue_fifo,
-    _Scheduler_EDF_SMP_Enqueue_scheduled_fifo
+    _Scheduler_EDF_SMP_Enqueue,
+    _Scheduler_EDF_SMP_Enqueue_scheduled
   );
 }
 
@@ -777,7 +683,7 @@ bool _Scheduler_EDF_SMP_Set_affinity(
     _Scheduler_EDF_SMP_Extract_from_ready,
     _Scheduler_EDF_SMP_Get_highest_ready,
     _Scheduler_EDF_SMP_Move_from_ready_to_scheduled,
-    _Scheduler_EDF_SMP_Enqueue_fifo,
+    _Scheduler_EDF_SMP_Enqueue,
     _Scheduler_EDF_SMP_Allocate_processor
   );
 
diff --git a/cpukit/score/src/scheduleredfunblock.c b/cpukit/score/src/scheduleredfunblock.c
index 29355d04fa..91295f511c 100644
--- a/cpukit/score/src/scheduleredfunblock.c
+++ b/cpukit/score/src/scheduleredfunblock.c
@@ -31,15 +31,16 @@ void _Scheduler_EDF_Unblock(
   Scheduler_EDF_Context *context;
   Scheduler_EDF_Node    *the_node;
   Priority_Control       priority;
-  bool                   prepend_it;
+  Priority_Control       insert_priority;
 
   context = _Scheduler_EDF_Get_context( scheduler );
   the_node = _Scheduler_EDF_Node_downcast( node );
-  priority = _Scheduler_Node_get_priority( &the_node->Base, &prepend_it );
-  (void) prepend_it;
+  priority = _Scheduler_Node_get_priority( &the_node->Base );
+  priority = SCHEDULER_PRIORITY_PURIFY( priority );
+  insert_priority = SCHEDULER_PRIORITY_APPEND( priority );
 
   the_node->priority = priority;
-  _Scheduler_EDF_Enqueue( context, the_node, priority );
+  _Scheduler_EDF_Enqueue( context, the_node, insert_priority );
 
   /*
    *  If the thread that was unblocked is more important than the heir,
diff --git a/cpukit/score/src/schedulerpriority.c b/cpukit/score/src/schedulerpriority.c
index ddfd973e0a..5ac16a49a1 100644
--- a/cpukit/score/src/schedulerpriority.c
+++ b/cpukit/score/src/schedulerpriority.c
@@ -19,7 +19,6 @@
 #endif
 
 #include <rtems/score/schedulerpriorityimpl.h>
-#include <rtems/score/wkspace.h>
 
 void _Scheduler_priority_Initialize( const Scheduler_Control *scheduler )
 {
@@ -49,7 +48,7 @@ void _Scheduler_priority_Node_initialize(
   the_node = _Scheduler_priority_Node_downcast( node );
   _Scheduler_priority_Ready_queue_update(
     &the_node->Ready_queue,
-    priority,
+    SCHEDULER_PRIORITY_UNMAP( priority ),
     &context->Bit_map,
     &context->Ready[ 0 ]
   );
diff --git a/cpukit/score/src/schedulerpriorityaffinitysmp.c b/cpukit/score/src/schedulerpriorityaffinitysmp.c
index 72b4ffb600..4808c84c3f 100644
--- a/cpukit/score/src/schedulerpriorityaffinitysmp.c
+++ b/cpukit/score/src/schedulerpriorityaffinitysmp.c
@@ -39,22 +39,13 @@
  *  + _Scheduler_priority_SMP_Do_update
  */
 
-static bool _Scheduler_priority_affinity_SMP_Insert_priority_lifo_order(
+static bool _Scheduler_priority_affinity_SMP_Priority_less_equal(
   const void       *to_insert,
   const Chain_Node *next
 )
 {
   return next != NULL
-    && _Scheduler_SMP_Insert_priority_lifo_order( to_insert, next );
-}
-
-static bool _Scheduler_priority_affinity_SMP_Insert_priority_fifo_order(
-  const void       *to_insert,
-  const Chain_Node *next
-)
-{
-  return next != NULL
-    && _Scheduler_SMP_Insert_priority_fifo_order( to_insert, next );
+    && _Scheduler_SMP_Priority_less_equal( to_insert, next );
 }
 
 static Scheduler_priority_affinity_SMP_Node *
@@ -242,19 +233,21 @@ static Scheduler_Node * _Scheduler_priority_affinity_SMP_Get_lowest_scheduled(
 /*
  * This method is unique to this scheduler because it must pass
  * _Scheduler_priority_affinity_SMP_Get_lowest_scheduled into
- * _Scheduler_SMP_Enqueue_ordered.
+ * _Scheduler_SMP_Enqueue.
  */
 static bool _Scheduler_priority_affinity_SMP_Enqueue_fifo(
   Scheduler_Context *context,
-  Scheduler_Node    *node
+  Scheduler_Node    *node,
+  Priority_Control   insert_priority
 )
 {
-  return _Scheduler_SMP_Enqueue_ordered(
+  return _Scheduler_SMP_Enqueue(
     context,
     node,
-    _Scheduler_priority_affinity_SMP_Insert_priority_fifo_order,
-    _Scheduler_priority_SMP_Insert_ready_fifo,
-    _Scheduler_SMP_Insert_scheduled_fifo,
+    insert_priority,
+    _Scheduler_priority_affinity_SMP_Priority_less_equal,
+    _Scheduler_priority_SMP_Insert_ready,
+    _Scheduler_SMP_Insert_scheduled,
     _Scheduler_priority_SMP_Move_from_scheduled_to_ready,
     _Scheduler_priority_affinity_SMP_Get_lowest_scheduled,
     _Scheduler_SMP_Allocate_processor_exact
@@ -280,6 +273,7 @@ static void _Scheduler_priority_affinity_SMP_Check_for_migrations(
 
   while (1) {
     Priority_Control lowest_scheduled_priority;
+    Priority_Control insert_priority;
 
     if ( _Priority_bit_map_Is_empty( &self->Bit_map ) ) {
       /* Nothing to do */
@@ -312,7 +306,7 @@ static void _Scheduler_priority_affinity_SMP_Check_for_migrations(
       _Scheduler_SMP_Node_priority( lowest_scheduled );
 
     if (
-      _Scheduler_SMP_Insert_priority_lifo_order(
+      _Scheduler_SMP_Priority_less_equal(
         &lowest_scheduled_priority,
         &highest_ready->Node.Chain
       )
@@ -326,11 +320,14 @@ static void _Scheduler_priority_affinity_SMP_Check_for_migrations(
      */
 
     _Scheduler_priority_SMP_Extract_from_ready( context, highest_ready );
+    insert_priority = _Scheduler_SMP_Node_priority( highest_ready );
+    insert_priority = SCHEDULER_PRIORITY_APPEND( insert_priority );
     _Scheduler_SMP_Enqueue_to_scheduled(
       context,
       highest_ready,
+      insert_priority,
       lowest_scheduled,
-      _Scheduler_SMP_Insert_scheduled_fifo,
+      _Scheduler_SMP_Insert_scheduled,
       _Scheduler_priority_SMP_Move_from_scheduled_to_ready,
       _Scheduler_SMP_Allocate_processor_exact
     );
@@ -364,22 +361,21 @@ void _Scheduler_priority_affinity_SMP_Unblock(
 
 /*
  *  This is unique to this scheduler because it passes scheduler specific
- *  get_lowest_scheduled helper to _Scheduler_SMP_Enqueue_ordered.
+ *  get_lowest_scheduled helper to _Scheduler_SMP_Enqueue.
  */
-static bool _Scheduler_priority_affinity_SMP_Enqueue_ordered(
-  Scheduler_Context     *context,
-  Scheduler_Node        *node,
-  Chain_Node_order       order,
-  Scheduler_SMP_Insert   insert_ready,
-  Scheduler_SMP_Insert   insert_scheduled
+static bool _Scheduler_priority_affinity_SMP_Enqueue(
+  Scheduler_Context *context,
+  Scheduler_Node    *node,
+  Priority_Control   insert_priority
 )
 {
-  return _Scheduler_SMP_Enqueue_ordered(
+  return _Scheduler_SMP_Enqueue(
     context,
     node,
-    order,
-    insert_ready,
-    insert_scheduled,
+    insert_priority,
+    _Scheduler_priority_affinity_SMP_Priority_less_equal,
+    _Scheduler_priority_SMP_Insert_ready,
+    _Scheduler_SMP_Insert_scheduled,
     _Scheduler_priority_SMP_Move_from_scheduled_to_ready,
     _Scheduler_priority_affinity_SMP_Get_lowest_scheduled,
     _Scheduler_SMP_Allocate_processor_exact
@@ -387,88 +383,30 @@ static bool _Scheduler_priority_affinity_SMP_Enqueue_ordered(
 }
 
 /*
- *  This is unique to this scheduler because it is on the path
- *  to _Scheduler_priority_affinity_SMP_Enqueue_ordered() which
- *  invokes a scheduler unique get_lowest_scheduled helper.
- */
-static bool _Scheduler_priority_affinity_SMP_Enqueue_lifo(
-  Scheduler_Context *context,
-  Scheduler_Node    *node
-)
-{
-  return _Scheduler_priority_affinity_SMP_Enqueue_ordered(
-    context,
-    node,
-    _Scheduler_priority_affinity_SMP_Insert_priority_lifo_order,
-    _Scheduler_priority_SMP_Insert_ready_lifo,
-    _Scheduler_SMP_Insert_scheduled_lifo
-  );
-}
-
-/*
  * This method is unique to this scheduler because it must
- * invoke _Scheduler_SMP_Enqueue_scheduled_ordered() with
+ * invoke _Scheduler_SMP_Enqueue_scheduled() with
  * this scheduler's get_highest_ready() helper.
  */
-static bool _Scheduler_priority_affinity_SMP_Enqueue_scheduled_ordered(
-  Scheduler_Context    *context,
-  Scheduler_Node       *node,
-  Chain_Node_order      order,
-  Scheduler_SMP_Insert  insert_ready,
-  Scheduler_SMP_Insert  insert_scheduled
+static bool _Scheduler_priority_affinity_SMP_Enqueue_scheduled(
+  Scheduler_Context *context,
+  Scheduler_Node    *node,
+  Priority_Control   insert_priority
 )
 {
-  return _Scheduler_SMP_Enqueue_scheduled_ordered(
+  return _Scheduler_SMP_Enqueue_scheduled(
     context,
     node,
-    order,
+    insert_priority,
+    _Scheduler_SMP_Priority_less_equal,
     _Scheduler_priority_SMP_Extract_from_ready,
     _Scheduler_priority_affinity_SMP_Get_highest_ready,
-    insert_ready,
-    insert_scheduled,
+    _Scheduler_priority_SMP_Insert_ready,
+    _Scheduler_SMP_Insert_scheduled,
     _Scheduler_priority_SMP_Move_from_ready_to_scheduled,
     _Scheduler_SMP_Allocate_processor_exact
   );
 }
 
-/*
- *  This is unique to this scheduler because it is on the path
- *  to _Scheduler_priority_affinity_SMP_Enqueue_scheduled__ordered() which
- *  invokes a scheduler unique get_lowest_scheduled helper.
- */
-static bool _Scheduler_priority_affinity_SMP_Enqueue_scheduled_lifo(
-  Scheduler_Context *context,
-  Scheduler_Node    *node
-)
-{
-  return _Scheduler_priority_affinity_SMP_Enqueue_scheduled_ordered(
-    context,
-    node,
-    _Scheduler_SMP_Insert_priority_lifo_order,
-    _Scheduler_priority_SMP_Insert_ready_lifo,
-    _Scheduler_SMP_Insert_scheduled_lifo
-  );
-}
-
-/*
- *  This is unique to this scheduler because it is on the path
- *  to _Scheduler_priority_affinity_SMP_Enqueue_scheduled__ordered() which
- *  invokes a scheduler unique get_lowest_scheduled helper.
- */
-static bool _Scheduler_priority_affinity_SMP_Enqueue_scheduled_fifo(
-  Scheduler_Context *context,
-  Scheduler_Node    *node
-)
-{
-  return _Scheduler_priority_affinity_SMP_Enqueue_scheduled_ordered(
-    context,
-    node,
-    _Scheduler_SMP_Insert_priority_fifo_order,
-    _Scheduler_priority_SMP_Insert_ready_fifo,
-    _Scheduler_SMP_Insert_scheduled_fifo
-  );
-}
-
 static bool _Scheduler_priority_affinity_SMP_Do_ask_for_help(
   Scheduler_Context *context,
   Thread_Control    *the_thread,
@@ -479,9 +417,9 @@ static bool _Scheduler_priority_affinity_SMP_Do_ask_for_help(
     context,
     the_thread,
     node,
-    _Scheduler_SMP_Insert_priority_lifo_order,
-    _Scheduler_priority_SMP_Insert_ready_lifo,
-    _Scheduler_SMP_Insert_scheduled_lifo,
+    _Scheduler_SMP_Priority_less_equal,
+    _Scheduler_priority_SMP_Insert_ready,
+    _Scheduler_SMP_Insert_scheduled,
     _Scheduler_priority_SMP_Move_from_scheduled_to_ready,
     _Scheduler_SMP_Get_lowest_scheduled,
     _Scheduler_SMP_Allocate_processor_lazy
@@ -502,10 +440,8 @@ void _Scheduler_priority_affinity_SMP_Update_priority(
     node,
     _Scheduler_priority_SMP_Extract_from_ready,
     _Scheduler_priority_SMP_Do_update,
-    _Scheduler_priority_affinity_SMP_Enqueue_fifo,
-    _Scheduler_priority_affinity_SMP_Enqueue_lifo,
-    _Scheduler_priority_affinity_SMP_Enqueue_scheduled_fifo,
-    _Scheduler_priority_affinity_SMP_Enqueue_scheduled_lifo,
+    _Scheduler_priority_affinity_SMP_Enqueue,
+    _Scheduler_priority_affinity_SMP_Enqueue_scheduled,
     _Scheduler_priority_affinity_SMP_Do_ask_for_help
   );
 
@@ -574,7 +510,7 @@ void _Scheduler_priority_affinity_SMP_Add_processor(
     context,
     idle,
     _Scheduler_priority_SMP_Has_ready,
-    _Scheduler_priority_affinity_SMP_Enqueue_scheduled_fifo,
+    _Scheduler_priority_affinity_SMP_Enqueue_scheduled,
     _Scheduler_SMP_Do_nothing_register_idle
   );
 }
@@ -590,7 +526,7 @@ Thread_Control *_Scheduler_priority_affinity_SMP_Remove_processor(
     context,
     cpu,
     _Scheduler_priority_SMP_Extract_from_ready,
-    _Scheduler_priority_affinity_SMP_Enqueue_fifo
+    _Scheduler_priority_affinity_SMP_Enqueue
   );
 }
 
diff --git a/cpukit/score/src/schedulerprioritychangepriority.c b/cpukit/score/src/schedulerprioritychangepriority.c
index eb640fe683..6af475a8d6 100644
--- a/cpukit/score/src/schedulerprioritychangepriority.c
+++ b/cpukit/score/src/schedulerprioritychangepriority.c
@@ -29,8 +29,8 @@ void _Scheduler_priority_Update_priority(
 {
   Scheduler_priority_Context *context;
   Scheduler_priority_Node    *the_node;
-  unsigned int                priority;
-  bool                        prepend_it;
+  unsigned int                new_priority;
+  unsigned int                unmapped_priority;
 
   if ( !_Thread_Is_ready( the_thread ) ) {
     /* Nothing to do */
@@ -38,10 +38,11 @@ void _Scheduler_priority_Update_priority(
   }
 
   the_node = _Scheduler_priority_Node_downcast( node );
-  priority = (unsigned int )
-    _Scheduler_Node_get_priority( &the_node->Base, &prepend_it );
+  new_priority = (unsigned int)
+    _Scheduler_Node_get_priority( &the_node->Base );
+  unmapped_priority = SCHEDULER_PRIORITY_UNMAP( new_priority );
 
-  if ( priority == the_node->Ready_queue.current_priority ) {
+  if ( unmapped_priority == the_node->Ready_queue.current_priority ) {
     /* Nothing to do */
     return;
   }
@@ -56,19 +57,19 @@ void _Scheduler_priority_Update_priority(
 
   _Scheduler_priority_Ready_queue_update(
     &the_node->Ready_queue,
-    priority,
+    unmapped_priority,
     &context->Bit_map,
     &context->Ready[ 0 ]
   );
 
-  if ( prepend_it ) {
-    _Scheduler_priority_Ready_queue_enqueue_first(
+  if ( SCHEDULER_PRIORITY_IS_APPEND( new_priority ) ) {
+    _Scheduler_priority_Ready_queue_enqueue(
       &the_thread->Object.Node,
       &the_node->Ready_queue,
       &context->Bit_map
     );
   } else {
-    _Scheduler_priority_Ready_queue_enqueue(
+    _Scheduler_priority_Ready_queue_enqueue_first(
       &the_thread->Object.Node,
       &the_node->Ready_queue,
       &context->Bit_map
diff --git a/cpukit/score/src/schedulerprioritysmp.c b/cpukit/score/src/schedulerprioritysmp.c
index 071a4218f3..205d3257ca 100644
--- a/cpukit/score/src/schedulerprioritysmp.c
+++ b/cpukit/score/src/schedulerprioritysmp.c
@@ -68,7 +68,7 @@ void _Scheduler_priority_SMP_Node_initialize(
   self = _Scheduler_priority_SMP_Get_self( context );
   _Scheduler_priority_Ready_queue_update(
     &the_node->Ready_queue,
-    priority,
+    SCHEDULER_PRIORITY_UNMAP( priority ),
     &self->Bit_map,
     &self->Ready[ 0 ]
   );
@@ -109,103 +109,45 @@ void _Scheduler_priority_SMP_Block(
   );
 }
 
-static bool _Scheduler_priority_SMP_Enqueue_ordered(
-  Scheduler_Context    *context,
-  Scheduler_Node       *node,
-  Chain_Node_order      order,
-  Scheduler_SMP_Insert  insert_ready,
-  Scheduler_SMP_Insert  insert_scheduled
+static bool _Scheduler_priority_SMP_Enqueue(
+  Scheduler_Context *context,
+  Scheduler_Node    *node,
+  Priority_Control   insert_priority
 )
 {
-  return _Scheduler_SMP_Enqueue_ordered(
+  return _Scheduler_SMP_Enqueue(
     context,
     node,
-    order,
-    insert_ready,
-    insert_scheduled,
+    insert_priority,
+    _Scheduler_SMP_Priority_less_equal,
+    _Scheduler_priority_SMP_Insert_ready,
+    _Scheduler_SMP_Insert_scheduled,
     _Scheduler_priority_SMP_Move_from_scheduled_to_ready,
     _Scheduler_SMP_Get_lowest_scheduled,
     _Scheduler_SMP_Allocate_processor_lazy
   );
 }
 
-static bool _Scheduler_priority_SMP_Enqueue_lifo(
-  Scheduler_Context *context,
-  Scheduler_Node    *node
-)
-{
-  return _Scheduler_priority_SMP_Enqueue_ordered(
-    context,
-    node,
-    _Scheduler_SMP_Insert_priority_lifo_order,
-    _Scheduler_priority_SMP_Insert_ready_lifo,
-    _Scheduler_SMP_Insert_scheduled_lifo
-  );
-}
-
-static bool _Scheduler_priority_SMP_Enqueue_fifo(
+static bool _Scheduler_priority_SMP_Enqueue_scheduled(
   Scheduler_Context *context,
-  Scheduler_Node    *node
+  Scheduler_Node    *node,
+  Priority_Control   insert_priority
 )
 {
-  return _Scheduler_priority_SMP_Enqueue_ordered(
+  return _Scheduler_SMP_Enqueue_scheduled(
     context,
     node,
-    _Scheduler_SMP_Insert_priority_fifo_order,
-    _Scheduler_priority_SMP_Insert_ready_fifo,
-    _Scheduler_SMP_Insert_scheduled_fifo
-  );
-}
-
-static bool _Scheduler_priority_SMP_Enqueue_scheduled_ordered(
-  Scheduler_Context *context,
-  Scheduler_Node *node,
-  Chain_Node_order order,
-  Scheduler_SMP_Insert insert_ready,
-  Scheduler_SMP_Insert insert_scheduled
-)
-{
-  return _Scheduler_SMP_Enqueue_scheduled_ordered(
-    context,
-    node,
-    order,
+    insert_priority,
+    _Scheduler_SMP_Priority_less_equal,
     _Scheduler_priority_SMP_Extract_from_ready,
     _Scheduler_priority_SMP_Get_highest_ready,
-    insert_ready,
-    insert_scheduled,
+    _Scheduler_priority_SMP_Insert_ready,
+    _Scheduler_SMP_Insert_scheduled,
     _Scheduler_priority_SMP_Move_from_ready_to_scheduled,
     _Scheduler_SMP_Allocate_processor_lazy
   );
 }
 
-static bool _Scheduler_priority_SMP_Enqueue_scheduled_lifo(
-  Scheduler_Context *context,
-  Scheduler_Node *node
-)
-{
-  return _Scheduler_priority_SMP_Enqueue_scheduled_ordered(
-    context,
-    node,
-    _Scheduler_SMP_Insert_priority_lifo_order,
-    _Scheduler_priority_SMP_Insert_ready_lifo,
-    _Scheduler_SMP_Insert_scheduled_lifo
-  );
-}
-
-static bool _Scheduler_priority_SMP_Enqueue_scheduled_fifo(
-  Scheduler_Context *context,
-  Scheduler_Node *node
-)
-{
-  return _Scheduler_priority_SMP_Enqueue_scheduled_ordered(
-    context,
-    node,
-    _Scheduler_SMP_Insert_priority_fifo_order,
-    _Scheduler_priority_SMP_Insert_ready_fifo,
-    _Scheduler_SMP_Insert_scheduled_fifo
-  );
-}
-
 void _Scheduler_priority_SMP_Unblock(
   const Scheduler_Control *scheduler,
   Thread_Control          *thread,
@@ -219,7 +161,7 @@ void _Scheduler_priority_SMP_Unblock(
     thread,
     node,
     _Scheduler_priority_SMP_Do_update,
-    _Scheduler_priority_SMP_Enqueue_fifo
+    _Scheduler_priority_SMP_Enqueue
   );
 }
 
@@ -233,9 +175,9 @@ static bool _Scheduler_priority_SMP_Do_ask_for_help(
     context,
     the_thread,
     node,
-    _Scheduler_SMP_Insert_priority_lifo_order,
-    _Scheduler_priority_SMP_Insert_ready_lifo,
-    _Scheduler_SMP_Insert_scheduled_lifo,
+    _Scheduler_SMP_Priority_less_equal,
+    _Scheduler_priority_SMP_Insert_ready,
+    _Scheduler_SMP_Insert_scheduled,
     _Scheduler_priority_SMP_Move_from_scheduled_to_ready,
     _Scheduler_SMP_Get_lowest_scheduled,
     _Scheduler_SMP_Allocate_processor_lazy
@@ -256,10 +198,8 @@ void _Scheduler_priority_SMP_Update_priority(
     node,
     _Scheduler_priority_SMP_Extract_from_ready,
     _Scheduler_priority_SMP_Do_update,
-    _Scheduler_priority_SMP_Enqueue_fifo,
-    _Scheduler_priority_SMP_Enqueue_lifo,
-    _Scheduler_priority_SMP_Enqueue_scheduled_fifo,
-    _Scheduler_priority_SMP_Enqueue_scheduled_lifo,
+    _Scheduler_priority_SMP_Enqueue,
+    _Scheduler_priority_SMP_Enqueue_scheduled,
     _Scheduler_priority_SMP_Do_ask_for_help
   );
 }
@@ -323,7 +263,7 @@ void _Scheduler_priority_SMP_Add_processor(
     context,
     idle,
     _Scheduler_priority_SMP_Has_ready,
-    _Scheduler_priority_SMP_Enqueue_scheduled_fifo,
+    _Scheduler_priority_SMP_Enqueue_scheduled,
     _Scheduler_SMP_Do_nothing_register_idle
   );
 }
@@ -339,7 +279,7 @@ Thread_Control *_Scheduler_priority_SMP_Remove_processor(
     context,
     cpu,
     _Scheduler_priority_SMP_Extract_from_ready,
-    _Scheduler_priority_SMP_Enqueue_fifo
+    _Scheduler_priority_SMP_Enqueue
   );
 }
 
@@ -356,7 +296,7 @@ void _Scheduler_priority_SMP_Yield(
     thread,
     node,
     _Scheduler_priority_SMP_Extract_from_ready,
-    _Scheduler_priority_SMP_Enqueue_fifo,
-    _Scheduler_priority_SMP_Enqueue_scheduled_fifo
+    _Scheduler_priority_SMP_Enqueue,
+    _Scheduler_priority_SMP_Enqueue_scheduled
   );
 }
diff --git a/cpukit/score/src/schedulerpriorityunblock.c b/cpukit/score/src/schedulerpriorityunblock.c
index 42ba4de98f..784bc58611 100644
--- a/cpukit/score/src/schedulerpriorityunblock.c
+++ b/cpukit/score/src/schedulerpriorityunblock.c
@@ -31,18 +31,17 @@ void _Scheduler_priority_Unblock (
   Scheduler_priority_Context *context;
   Scheduler_priority_Node    *the_node;
   unsigned int                priority;
-  bool                        prepend_it;
+  unsigned int                unmapped_priority;
 
   context = _Scheduler_priority_Get_context( scheduler );
   the_node = _Scheduler_priority_Node_downcast( node );
-  priority = (unsigned int )
-    _Scheduler_Node_get_priority( &the_node->Base, &prepend_it );
-  (void) prepend_it;
+  priority = (unsigned int ) _Scheduler_Node_get_priority( &the_node->Base );
+  unmapped_priority = SCHEDULER_PRIORITY_UNMAP( priority );
 
-  if ( priority != the_node->Ready_queue.current_priority ) {
+  if ( unmapped_priority != the_node->Ready_queue.current_priority ) {
     _Scheduler_priority_Ready_queue_update(
       &the_node->Ready_queue,
-      priority,
+      unmapped_priority,
       &context->Bit_map,
       &context->Ready[ 0 ]
     );
diff --git a/cpukit/score/src/schedulersimplechangepriority.c b/cpukit/score/src/schedulersimplechangepriority.c
index 8253a01421..c2c60a5f01 100644
--- a/cpukit/score/src/schedulersimplechangepriority.c
+++ b/cpukit/score/src/schedulersimplechangepriority.c
@@ -28,7 +28,7 @@ void _Scheduler_simple_Update_priority(
 )
 {
   Scheduler_simple_Context *context;
-  bool                      prepend_it;
+  unsigned int              new_priority;
 
   if ( !_Thread_Is_ready( the_thread ) ) {
     /* Nothing to do */
@@ -36,15 +36,9 @@ void _Scheduler_simple_Update_priority(
   }
 
   context = _Scheduler_simple_Get_context( scheduler );
-  _Scheduler_Node_get_priority( node, &prepend_it );
+  new_priority = (unsigned int ) _Scheduler_Node_get_priority( node );
 
   _Scheduler_simple_Extract( scheduler, the_thread, node );
-
-  if ( prepend_it ) {
-    _Scheduler_simple_Insert_priority_lifo( &context->Ready, the_thread );
-  } else {
-    _Scheduler_simple_Insert_priority_fifo( &context->Ready, the_thread );
-  }
-
+  _Scheduler_simple_Insert( &context->Ready, the_thread, new_priority );
   _Scheduler_simple_Schedule_body( scheduler, the_thread, false );
 }
diff --git a/cpukit/score/src/schedulersimplesmp.c b/cpukit/score/src/schedulersimplesmp.c
index df08a19eab..4ab4987c3a 100644
--- a/cpukit/score/src/schedulersimplesmp.c
+++ b/cpukit/score/src/schedulersimplesmp.c
@@ -99,17 +99,17 @@ static void _Scheduler_simple_SMP_Move_from_scheduled_to_ready(
 )
 {
   Scheduler_simple_SMP_Context *self;
-  Priority_Control              priority_to_insert;
+  Priority_Control              insert_priority;
 
   self = _Scheduler_simple_SMP_Get_self( context );
-  priority_to_insert = _Scheduler_SMP_Node_priority( scheduled_to_ready );
 
   _Chain_Extract_unprotected( &scheduled_to_ready->Node.Chain );
+  insert_priority = _Scheduler_SMP_Node_priority( scheduled_to_ready );
   _Chain_Insert_ordered_unprotected(
     &self->Ready,
     &scheduled_to_ready->Node.Chain,
-    &priority_to_insert,
-    _Scheduler_SMP_Insert_priority_lifo_order
+    &insert_priority,
+    _Scheduler_SMP_Priority_less_equal
   );
 }
 
@@ -119,55 +119,36 @@ static void _Scheduler_simple_SMP_Move_from_ready_to_scheduled(
 )
 {
   Scheduler_simple_SMP_Context *self;
-  Priority_Control              priority_to_insert;
+  Priority_Control              insert_priority;
 
   self = _Scheduler_simple_SMP_Get_self( context );
-  priority_to_insert = _Scheduler_SMP_Node_priority( ready_to_scheduled );
 
   _Chain_Extract_unprotected( &ready_to_scheduled->Node.Chain );
+  insert_priority = _Scheduler_SMP_Node_priority( ready_to_scheduled );
+  insert_priority = SCHEDULER_PRIORITY_APPEND( insert_priority );
   _Chain_Insert_ordered_unprotected(
     &self->Base.Scheduled,
     &ready_to_scheduled->Node.Chain,
-    &priority_to_insert,
-    _Scheduler_SMP_Insert_priority_fifo_order
+    &insert_priority,
+    _Scheduler_SMP_Priority_less_equal
   );
 }
 
-static void _Scheduler_simple_SMP_Insert_ready_lifo(
+static void _Scheduler_simple_SMP_Insert_ready(
   Scheduler_Context *context,
-  Scheduler_Node    *node_to_insert
+  Scheduler_Node    *node_to_insert,
+  Priority_Control   insert_priority
 )
 {
   Scheduler_simple_SMP_Context *self;
-  Priority_Control              priority_to_insert;
 
   self = _Scheduler_simple_SMP_Get_self( context );
-  priority_to_insert = _Scheduler_SMP_Node_priority( node_to_insert );
 
   _Chain_Insert_ordered_unprotected(
     &self->Ready,
     &node_to_insert->Node.Chain,
-    &priority_to_insert,
-    _Scheduler_SMP_Insert_priority_lifo_order
-  );
-}
-
-static void _Scheduler_simple_SMP_Insert_ready_fifo(
-  Scheduler_Context *context,
-  Scheduler_Node    *node_to_insert
-)
-{
-  Scheduler_simple_SMP_Context *self;
-  Priority_Control              priority_to_insert;
-
-  self = _Scheduler_simple_SMP_Get_self( context );
-  priority_to_insert = _Scheduler_SMP_Node_priority( node_to_insert );
-
-  _Chain_Insert_ordered_unprotected(
-    &self->Ready,
-    &node_to_insert->Node.Chain,
-    &priority_to_insert,
-    _Scheduler_SMP_Insert_priority_fifo_order
+    &insert_priority,
+    _Scheduler_SMP_Priority_less_equal
   );
 }
 
@@ -200,103 +181,45 @@ void _Scheduler_simple_SMP_Block(
   );
 }
 
-static bool _Scheduler_simple_SMP_Enqueue_ordered(
-  Scheduler_Context    *context,
-  Scheduler_Node       *node,
-  Chain_Node_order      order,
-  Scheduler_SMP_Insert  insert_ready,
-  Scheduler_SMP_Insert  insert_scheduled
+static bool _Scheduler_simple_SMP_Enqueue(
+  Scheduler_Context *context,
+  Scheduler_Node    *node,
+  Priority_Control   insert_priority
 )
 {
-  return _Scheduler_SMP_Enqueue_ordered(
+  return _Scheduler_SMP_Enqueue(
     context,
     node,
-    order,
-    insert_ready,
-    insert_scheduled,
+    insert_priority,
+    _Scheduler_SMP_Priority_less_equal,
+    _Scheduler_simple_SMP_Insert_ready,
+    _Scheduler_SMP_Insert_scheduled,
     _Scheduler_simple_SMP_Move_from_scheduled_to_ready,
     _Scheduler_SMP_Get_lowest_scheduled,
     _Scheduler_SMP_Allocate_processor_lazy
   );
 }
 
-static bool _Scheduler_simple_SMP_Enqueue_lifo(
-  Scheduler_Context *context,
-  Scheduler_Node    *node
-)
-{
-  return _Scheduler_simple_SMP_Enqueue_ordered(
-    context,
-    node,
-    _Scheduler_SMP_Insert_priority_lifo_order,
-    _Scheduler_simple_SMP_Insert_ready_lifo,
-    _Scheduler_SMP_Insert_scheduled_lifo
-  );
-}
-
-static bool _Scheduler_simple_SMP_Enqueue_fifo(
-  Scheduler_Context *context,
-  Scheduler_Node    *node
-)
-{
-  return _Scheduler_simple_SMP_Enqueue_ordered(
-    context,
-    node,
-    _Scheduler_SMP_Insert_priority_fifo_order,
-    _Scheduler_simple_SMP_Insert_ready_fifo,
-    _Scheduler_SMP_Insert_scheduled_fifo
-  );
-}
-
-static bool _Scheduler_simple_SMP_Enqueue_scheduled_ordered(
+static bool _Scheduler_simple_SMP_Enqueue_scheduled(
   Scheduler_Context *context,
-  Scheduler_Node *node,
-  Chain_Node_order order,
-  Scheduler_SMP_Insert insert_ready,
-  Scheduler_SMP_Insert insert_scheduled
+  Scheduler_Node    *node,
+  Priority_Control   insert_priority
 )
 {
-  return _Scheduler_SMP_Enqueue_scheduled_ordered(
+  return _Scheduler_SMP_Enqueue_scheduled(
     context,
     node,
-    order,
+    insert_priority,
+    _Scheduler_SMP_Priority_less_equal,
     _Scheduler_simple_SMP_Extract_from_ready,
     _Scheduler_simple_SMP_Get_highest_ready,
-    insert_ready,
-    insert_scheduled,
+    _Scheduler_simple_SMP_Insert_ready,
+    _Scheduler_SMP_Insert_scheduled,
     _Scheduler_simple_SMP_Move_from_ready_to_scheduled,
     _Scheduler_SMP_Allocate_processor_lazy
   );
 }
 
-static bool _Scheduler_simple_SMP_Enqueue_scheduled_lifo(
-  Scheduler_Context *context,
-  Scheduler_Node *node
-)
-{
-  return _Scheduler_simple_SMP_Enqueue_scheduled_ordered(
-    context,
-    node,
-    _Scheduler_SMP_Insert_priority_lifo_order,
-    _Scheduler_simple_SMP_Insert_ready_lifo,
-    _Scheduler_SMP_Insert_scheduled_lifo
-  );
-}
-
-static bool _Scheduler_simple_SMP_Enqueue_scheduled_fifo(
-  Scheduler_Context *context,
-  Scheduler_Node *node
-)
-{
-  return _Scheduler_simple_SMP_Enqueue_scheduled_ordered(
-    context,
-    node,
-    _Scheduler_SMP_Insert_priority_fifo_order,
-    _Scheduler_simple_SMP_Insert_ready_fifo,
-    _Scheduler_SMP_Insert_scheduled_fifo
-  );
-}
-
 void _Scheduler_simple_SMP_Unblock(
   const Scheduler_Control *scheduler,
   Thread_Control          *thread,
@@ -310,7 +233,7 @@ void _Scheduler_simple_SMP_Unblock(
     thread,
     node,
     _Scheduler_simple_SMP_Do_update,
-    _Scheduler_simple_SMP_Enqueue_fifo
+    _Scheduler_simple_SMP_Enqueue
   );
 }
 
@@ -324,9 +247,9 @@ static bool _Scheduler_simple_SMP_Do_ask_for_help(
     context,
     the_thread,
     node,
-    _Scheduler_SMP_Insert_priority_lifo_order,
-    _Scheduler_simple_SMP_Insert_ready_lifo,
-    _Scheduler_SMP_Insert_scheduled_lifo,
+    _Scheduler_SMP_Priority_less_equal,
+    _Scheduler_simple_SMP_Insert_ready,
+    _Scheduler_SMP_Insert_scheduled,
     _Scheduler_simple_SMP_Move_from_scheduled_to_ready,
     _Scheduler_SMP_Get_lowest_scheduled,
     _Scheduler_SMP_Allocate_processor_lazy
@@ -347,10 +270,8 @@ void _Scheduler_simple_SMP_Update_priority(
     node,
     _Scheduler_simple_SMP_Extract_from_ready,
     _Scheduler_simple_SMP_Do_update,
-    _Scheduler_simple_SMP_Enqueue_fifo,
-    _Scheduler_simple_SMP_Enqueue_lifo,
-    _Scheduler_simple_SMP_Enqueue_scheduled_fifo,
-    _Scheduler_simple_SMP_Enqueue_scheduled_lifo,
+    _Scheduler_simple_SMP_Enqueue,
+    _Scheduler_simple_SMP_Enqueue_scheduled,
     _Scheduler_simple_SMP_Do_ask_for_help
   );
 }
@@ -414,7 +335,7 @@ void _Scheduler_simple_SMP_Add_processor(
     context,
     idle,
     _Scheduler_simple_SMP_Has_ready,
-    _Scheduler_simple_SMP_Enqueue_scheduled_fifo,
+    _Scheduler_simple_SMP_Enqueue_scheduled,
     _Scheduler_SMP_Do_nothing_register_idle
   );
 }
@@ -430,7 +351,7 @@ Thread_Control *_Scheduler_simple_SMP_Remove_processor(
     context,
     cpu,
     _Scheduler_simple_SMP_Extract_from_ready,
-    _Scheduler_simple_SMP_Enqueue_fifo
+    _Scheduler_simple_SMP_Enqueue
   );
 }
 
@@ -447,7 +368,7 @@ void _Scheduler_simple_SMP_Yield(
     thread,
     node,
     _Scheduler_simple_SMP_Extract_from_ready,
-    _Scheduler_simple_SMP_Enqueue_fifo,
-    _Scheduler_simple_SMP_Enqueue_scheduled_fifo
+    _Scheduler_simple_SMP_Enqueue,
+    _Scheduler_simple_SMP_Enqueue_scheduled
   );
 }
diff --git a/cpukit/score/src/schedulersimpleunblock.c b/cpukit/score/src/schedulersimpleunblock.c
index 5540e20e87..2f5c8636f5 100644
--- a/cpukit/score/src/schedulersimpleunblock.c
+++ b/cpukit/score/src/schedulersimpleunblock.c
@@ -28,13 +28,15 @@ void _Scheduler_simple_Unblock(
 )
 {
   Scheduler_simple_Context *context;
-  Priority_Control          priority;
+  unsigned int              priority;
+  unsigned int              insert_priority;
 
   (void) node;
 
   context = _Scheduler_simple_Get_context( scheduler );
-  _Scheduler_simple_Insert_priority_fifo( &context->Ready, the_thread );
   priority = _Thread_Get_priority( the_thread );
+  insert_priority = SCHEDULER_PRIORITY_APPEND( priority );
+  _Scheduler_simple_Insert( &context->Ready, the_thread, insert_priority );
 
   /*
    *  If the thread that was unblocked is more important than the heir,
diff --git a/cpukit/score/src/schedulersimpleyield.c b/cpukit/score/src/schedulersimpleyield.c
index 0c150d8b1f..95f9cd3540 100644
--- a/cpukit/score/src/schedulersimpleyield.c
+++ b/cpukit/score/src/schedulersimpleyield.c
@@ -26,12 +26,16 @@ void _Scheduler_simple_Yield(
   Scheduler_Node          *node
 )
 {
-  Scheduler_simple_Context *context =
-    _Scheduler_simple_Get_context( scheduler );
+  Scheduler_simple_Context *context;
+  unsigned int              insert_priority;
+
+  context = _Scheduler_simple_Get_context( scheduler );
 
   (void) node;
 
   _Chain_Extract_unprotected( &the_thread->Object.Node );
-  _Scheduler_simple_Insert_priority_fifo( &context->Ready, the_thread );
+  insert_priority = (unsigned int) _Thread_Get_priority( the_thread );
+  insert_priority = SCHEDULER_PRIORITY_APPEND( insert_priority );
+  _Scheduler_simple_Insert( &context->Ready, the_thread, insert_priority );
   _Scheduler_simple_Schedule_body( scheduler, the_thread, false );
 }
diff --git a/cpukit/score/src/schedulerstrongapa.c b/cpukit/score/src/schedulerstrongapa.c
index 57ffb61367..19d4ebe348 100644
--- a/cpukit/score/src/schedulerstrongapa.c
+++ b/cpukit/score/src/schedulerstrongapa.c
@@ -66,7 +66,7 @@ static void _Scheduler_strong_APA_Move_from_ready_to_scheduled(
 {
   Scheduler_strong_APA_Context *self;
   Scheduler_strong_APA_Node    *node;
-  Priority_Control              priority;
+  Priority_Control              insert_priority;
 
   self = _Scheduler_strong_APA_Get_self( context );
   node = _Scheduler_strong_APA_Node_downcast( ready_to_scheduled );
@@ -76,47 +76,41 @@ static void _Scheduler_strong_APA_Move_from_ready_to_scheduled(
     &node->Ready_queue,
     &self->Bit_map
   );
-  priority = node->Base.priority;
+  insert_priority = _Scheduler_SMP_Node_priority( &node->Base.Base );
+  insert_priority = SCHEDULER_PRIORITY_APPEND( insert_priority );
   _Chain_Insert_ordered_unprotected(
     &self->Base.Scheduled,
     &node->Base.Base.Node.Chain,
-    &priority,
-    _Scheduler_SMP_Insert_priority_fifo_order
+    &insert_priority,
+    _Scheduler_SMP_Priority_less_equal
   );
 }
 
-static void _Scheduler_strong_APA_Insert_ready_lifo(
+static void _Scheduler_strong_APA_Insert_ready(
   Scheduler_Context *context,
-  Scheduler_Node    *the_thread
-)
-{
-  Scheduler_strong_APA_Context *self =
-    _Scheduler_strong_APA_Get_self( context );
-  Scheduler_strong_APA_Node *node =
-    _Scheduler_strong_APA_Node_downcast( the_thread );
-
-  _Scheduler_priority_Ready_queue_enqueue(
-    &node->Base.Base.Node.Chain,
-    &node->Ready_queue,
-    &self->Bit_map
-  );
-}
-
-static void _Scheduler_strong_APA_Insert_ready_fifo(
-  Scheduler_Context *context,
-  Scheduler_Node    *the_thread
+  Scheduler_Node    *node_base,
+  Priority_Control   insert_priority
 )
 {
-  Scheduler_strong_APA_Context *self =
-    _Scheduler_strong_APA_Get_self( context );
-  Scheduler_strong_APA_Node *node =
-    _Scheduler_strong_APA_Node_downcast( the_thread );
+  Scheduler_strong_APA_Context *self;
+  Scheduler_strong_APA_Node    *node;
 
-  _Scheduler_priority_Ready_queue_enqueue_first(
-    &node->Base.Base.Node.Chain,
-    &node->Ready_queue,
-    &self->Bit_map
-  );
+  self = _Scheduler_strong_APA_Get_self( context );
+  node = _Scheduler_strong_APA_Node_downcast( node_base );
+
+  if ( SCHEDULER_PRIORITY_IS_APPEND( insert_priority ) ) {
+    _Scheduler_priority_Ready_queue_enqueue(
+      &node->Base.Base.Node.Chain,
+      &node->Ready_queue,
+      &self->Bit_map
+    );
+  } else {
+    _Scheduler_priority_Ready_queue_enqueue_first(
+      &node->Base.Base.Node.Chain,
+      &node->Ready_queue,
+      &self->Bit_map
+    );
+  }
 }
 
 static void _Scheduler_strong_APA_Extract_from_ready(
@@ -150,7 +144,7 @@ static void _Scheduler_strong_APA_Do_update(
   _Scheduler_SMP_Node_update_priority( &node->Base, new_priority );
   _Scheduler_priority_Ready_queue_update(
     &node->Ready_queue,
-    new_priority,
+    SCHEDULER_PRIORITY_UNMAP( new_priority ),
     &self->Bit_map,
     &self->Ready[ 0 ]
   );
@@ -198,7 +192,7 @@ void _Scheduler_strong_APA_Node_initialize(
   self = _Scheduler_strong_APA_Get_self( context );
   _Scheduler_priority_Ready_queue_update(
     &the_node->Ready_queue,
-    priority,
+    SCHEDULER_PRIORITY_UNMAP( priority ),
     &self->Bit_map,
     &self->Ready[ 0 ]
   );
@@ -247,103 +241,45 @@ void _Scheduler_strong_APA_Block(
   );
 }
 
-static bool _Scheduler_strong_APA_Enqueue_ordered(
-  Scheduler_Context    *context,
-  Scheduler_Node       *node,
-  Chain_Node_order      order,
-  Scheduler_SMP_Insert  insert_ready,
-  Scheduler_SMP_Insert  insert_scheduled
+static bool _Scheduler_strong_APA_Enqueue(
+  Scheduler_Context *context,
+  Scheduler_Node    *node,
+  Priority_Control   insert_priority
 )
 {
-  return _Scheduler_SMP_Enqueue_ordered(
+  return _Scheduler_SMP_Enqueue(
     context,
     node,
-    order,
-    insert_ready,
-    insert_scheduled,
+    insert_priority,
+    _Scheduler_SMP_Priority_less_equal,
+    _Scheduler_strong_APA_Insert_ready,
+    _Scheduler_SMP_Insert_scheduled,
     _Scheduler_strong_APA_Move_from_scheduled_to_ready,
     _Scheduler_SMP_Get_lowest_scheduled,
     _Scheduler_SMP_Allocate_processor_exact
   );
 }
 
-static bool _Scheduler_strong_APA_Enqueue_lifo(
-  Scheduler_Context *context,
-  Scheduler_Node    *node
-)
-{
-  return _Scheduler_strong_APA_Enqueue_ordered(
-    context,
-    node,
-    _Scheduler_SMP_Insert_priority_lifo_order,
-    _Scheduler_strong_APA_Insert_ready_lifo,
-    _Scheduler_SMP_Insert_scheduled_lifo
-  );
-}
-
-static bool _Scheduler_strong_APA_Enqueue_fifo(
+static bool _Scheduler_strong_APA_Enqueue_scheduled(
   Scheduler_Context *context,
-  Scheduler_Node    *node
-)
-{
-  return _Scheduler_strong_APA_Enqueue_ordered(
-    context,
-    node,
-    _Scheduler_SMP_Insert_priority_fifo_order,
-    _Scheduler_strong_APA_Insert_ready_fifo,
-    _Scheduler_SMP_Insert_scheduled_fifo
-  );
-}
-
-static bool _Scheduler_strong_APA_Enqueue_scheduled_ordered(
-  Scheduler_Context    *context,
-  Scheduler_Node       *node,
-  Chain_Node_order      order,
-  Scheduler_SMP_Insert  insert_ready,
-  Scheduler_SMP_Insert  insert_scheduled
+  Scheduler_Node    *node,
+  Priority_Control  insert_priority
 )
 {
-  return _Scheduler_SMP_Enqueue_scheduled_ordered(
+  return _Scheduler_SMP_Enqueue_scheduled(
     context,
     node,
-    order,
+    insert_priority,
+    _Scheduler_SMP_Priority_less_equal,
     _Scheduler_strong_APA_Extract_from_ready,
     _Scheduler_strong_APA_Get_highest_ready,
-    insert_ready,
-    insert_scheduled,
+    _Scheduler_strong_APA_Insert_ready,
+    _Scheduler_SMP_Insert_scheduled,
     _Scheduler_strong_APA_Move_from_ready_to_scheduled,
     _Scheduler_SMP_Allocate_processor_exact
   );
 }
 
-static bool _Scheduler_strong_APA_Enqueue_scheduled_lifo(
-  Scheduler_Context *context,
-  Scheduler_Node    *node
-)
-{
-  return _Scheduler_strong_APA_Enqueue_scheduled_ordered(
-    context,
-    node,
-    _Scheduler_SMP_Insert_priority_lifo_order,
-    _Scheduler_strong_APA_Insert_ready_lifo,
-    _Scheduler_SMP_Insert_scheduled_lifo
-  );
-}
-
-static bool _Scheduler_strong_APA_Enqueue_scheduled_fifo(
-  Scheduler_Context *context,
-  Scheduler_Node    *node
-)
-{
-  return _Scheduler_strong_APA_Enqueue_scheduled_ordered(
-    context,
-    node,
-    _Scheduler_SMP_Insert_priority_fifo_order,
-    _Scheduler_strong_APA_Insert_ready_fifo,
-    _Scheduler_SMP_Insert_scheduled_fifo
-  );
-}
-
 void _Scheduler_strong_APA_Unblock(
   const Scheduler_Control *scheduler,
   Thread_Control          *the_thread,
@@ -357,7 +293,7 @@ void _Scheduler_strong_APA_Unblock(
     the_thread,
     node,
     _Scheduler_strong_APA_Do_update,
-    _Scheduler_strong_APA_Enqueue_fifo
+    _Scheduler_strong_APA_Enqueue
   );
 }
 
@@ -371,9 +307,9 @@ static bool _Scheduler_strong_APA_Do_ask_for_help(
     context,
     the_thread,
     node,
-    _Scheduler_SMP_Insert_priority_lifo_order,
-    _Scheduler_strong_APA_Insert_ready_lifo,
-    _Scheduler_SMP_Insert_scheduled_lifo,
+    _Scheduler_SMP_Priority_less_equal,
+    _Scheduler_strong_APA_Insert_ready,
+    _Scheduler_SMP_Insert_scheduled,
     _Scheduler_strong_APA_Move_from_scheduled_to_ready,
     _Scheduler_SMP_Get_lowest_scheduled,
     _Scheduler_SMP_Allocate_processor_lazy
@@ -394,10 +330,8 @@ void _Scheduler_strong_APA_Update_priority(
     node,
     _Scheduler_strong_APA_Extract_from_ready,
     _Scheduler_strong_APA_Do_update,
-    _Scheduler_strong_APA_Enqueue_fifo,
-    _Scheduler_strong_APA_Enqueue_lifo,
-    _Scheduler_strong_APA_Enqueue_scheduled_fifo,
-    _Scheduler_strong_APA_Enqueue_scheduled_lifo,
+    _Scheduler_strong_APA_Enqueue,
+    _Scheduler_strong_APA_Enqueue_scheduled,
     _Scheduler_strong_APA_Do_ask_for_help
   );
 }
@@ -461,7 +395,7 @@ void _Scheduler_strong_APA_Add_processor(
     context,
     idle,
     _Scheduler_strong_APA_Has_ready,
-    _Scheduler_strong_APA_Enqueue_scheduled_fifo,
+    _Scheduler_strong_APA_Enqueue_scheduled,
     _Scheduler_SMP_Do_nothing_register_idle
   );
 }
@@ -477,7 +411,7 @@ Thread_Control *_Scheduler_strong_APA_Remove_processor(
     context,
     cpu,
     _Scheduler_strong_APA_Extract_from_ready,
-    _Scheduler_strong_APA_Enqueue_fifo
+    _Scheduler_strong_APA_Enqueue
   );
 }
 
@@ -494,7 +428,7 @@ void _Scheduler_strong_APA_Yield(
     the_thread,
     node,
     _Scheduler_strong_APA_Extract_from_ready,
-    _Scheduler_strong_APA_Enqueue_fifo,
-    _Scheduler_strong_APA_Enqueue_scheduled_fifo
+    _Scheduler_strong_APA_Enqueue,
+    _Scheduler_strong_APA_Enqueue_scheduled
   );
 }