2010-11-24 Gedare Bloom <giddyup44@yahoo.com>

	PR 1647/cpukit
	* posix/src/nanosleep.c, posix/src/sched_yield.c,
	rtems/src/taskwakeafter.c, sapi/include/confdefs.h,
	sapi/include/rtems/config.h, sapi/src/exinit.c, score/Makefile.am,
	score/preinstall.am, score/include/rtems/score/prioritybitmap.h,
	score/include/rtems/score/thread.h,
	score/inline/rtems/score/thread.inl, score/src/thread.c,
	score/src/threadchangepriority.c, score/src/threadclearstate.c,
	score/src/threadclose.c, score/src/threadinitialize.c,
	score/src/threadready.c, score/src/threadresume.c,
	score/src/threadsetpriority.c, score/src/threadsetstate.c,
	score/src/threadsettransient.c,	score/src/threadsuspend.c,
	score/src/threadtickletimeslice.c: Refactor scheduler out of thread
	handler to facilitate alternate scheduler implementations.
	* score/src/threadyieldprocessor.c: Removed.
	* score/src/schedulerprioritythreadschedulerupdate.c,
	score/src/schedulerprioritythreadschedulerfree.c,
	score/src/schedulerpriorityblock.c, score/src/scheduler.c,
	score/src/schedulerprioritythreadschedulerallocate.c,
	score/src/schedulerpriorityunblock.c,
	score/src/schedulerpriority.c, score/src/schedulerpriorityyield.c,
	score/include/rtems/score/schedulerpriority.h,
	score/include/rtems/score/scheduler.h,
	score/inline/rtems/score/scheduler.inl,
	score/inline/rtems/score/schedulerpriority.inl: New files.

37 files changed, 1434 insertions, 164 deletions

diff --git a/cpukit/ChangeLog b/cpukit/ChangeLog
index 3ee1ccc9aa..9a1cfcb872 100644
--- a/cpukit/ChangeLog
+++ b/cpukit/ChangeLog
@@ -1,3 +1,31 @@
+2010-11-24	Gedare Bloom <giddyup44@yahoo.com>
+
+	PR 1647/cpukit
+	* posix/src/nanosleep.c, posix/src/sched_yield.c,
+	rtems/src/taskwakeafter.c, sapi/include/confdefs.h,
+	sapi/include/rtems/config.h, sapi/src/exinit.c, score/Makefile.am,
+	score/preinstall.am, score/include/rtems/score/prioritybitmap.h,
+	score/include/rtems/score/thread.h,
+	score/inline/rtems/score/thread.inl, score/src/thread.c,
+	score/src/threadchangepriority.c, score/src/threadclearstate.c,
+	score/src/threadclose.c, score/src/threadinitialize.c,
+	score/src/threadready.c, score/src/threadresume.c,
+	score/src/threadsetpriority.c, score/src/threadsetstate.c,
+	score/src/threadsettransient.c,	score/src/threadsuspend.c,
+	score/src/threadtickletimeslice.c: Refactor scheduler out of thread
+	handler to facilitate alternate scheduler implementations.
+	* score/src/threadyieldprocessor.c: Removed.
+	* score/src/schedulerprioritythreadschedulerupdate.c,
+	score/src/schedulerprioritythreadschedulerfree.c,
+	score/src/schedulerpriorityblock.c, score/src/scheduler.c,
+	score/src/schedulerprioritythreadschedulerallocate.c,
+	score/src/schedulerpriorityunblock.c,
+	score/src/schedulerpriority.c, score/src/schedulerpriorityyield.c,
+	score/include/rtems/score/schedulerpriority.h,
+	score/include/rtems/score/scheduler.h,
+	score/inline/rtems/score/scheduler.inl, 
+	score/inline/rtems/score/schedulerpriority.inl: New files.
+
 2010-11-23	Sebastian Huber <sebastian.huber@embedded-brains.de>
 
 	* score/src/iterateoverthreads.c, libmisc/cpuuse/cpuusagereport.c:
diff --git a/cpukit/posix/src/nanosleep.c b/cpukit/posix/src/nanosleep.c
index 5031039c24..dc81a378d5 100644
--- a/cpukit/posix/src/nanosleep.c
+++ b/cpukit/posix/src/nanosleep.c
@@ -18,6 +18,7 @@
 
 #include <rtems/system.h>
 #include <rtems/score/isr.h>
+#include <rtems/score/scheduler.h>
 #include <rtems/score/thread.h>
 #include <rtems/score/tod.h>
 
@@ -56,7 +57,7 @@ int nanosleep(
 
   if ( !ticks ) {
     _Thread_Disable_dispatch();
-      _Thread_Yield_processor();
+      _Scheduler_Yield();
     _Thread_Enable_dispatch();
     if ( rmtp ) {
        rmtp->tv_sec = 0;
diff --git a/cpukit/posix/src/sched_yield.c b/cpukit/posix/src/sched_yield.c
index 0925e3cbd0..b6c5c4fce4 100644
--- a/cpukit/posix/src/sched_yield.c
+++ b/cpukit/posix/src/sched_yield.c
@@ -19,6 +19,7 @@
 #include <errno.h>
 
 #include <rtems/system.h>
+#include <rtems/score/scheduler.h>
 #include <rtems/score/tod.h>
 #include <rtems/score/thread.h>
 #include <rtems/seterr.h>
@@ -28,7 +29,7 @@
 int sched_yield( void )
 {
   _Thread_Disable_dispatch();
-    _Thread_Yield_processor();
+    _Scheduler_Yield();
   _Thread_Enable_dispatch();
   return 0;
 }
diff --git a/cpukit/rtems/src/taskwakeafter.c b/cpukit/rtems/src/taskwakeafter.c
index 85f2e6307d..2f6fecfe5d 100644
--- a/cpukit/rtems/src/taskwakeafter.c
+++ b/cpukit/rtems/src/taskwakeafter.c
@@ -21,6 +21,7 @@
 #include <rtems/rtems/support.h>
 #include <rtems/rtems/modes.h>
 #include <rtems/score/object.h>
+#include <rtems/score/scheduler.h>
 #include <rtems/score/stack.h>
 #include <rtems/score/states.h>
 #include <rtems/rtems/tasks.h>
@@ -52,7 +53,7 @@ rtems_status_code rtems_task_wake_after(
 {
   _Thread_Disable_dispatch();
     if ( ticks == 0 ) {
-      _Thread_Yield_processor();
+      _Scheduler_Yield();
     } else {
       _Thread_Set_state( _Thread_Executing, STATES_DELAYING );
       _Watchdog_Initialize(
diff --git a/cpukit/sapi/include/confdefs.h b/cpukit/sapi/include/confdefs.h
index e6f8edaed2..0a1b49d173 100644
--- a/cpukit/sapi/include/confdefs.h
+++ b/cpukit/sapi/include/confdefs.h
@@ -535,6 +535,116 @@ rtems_fs_init_functions_t    rtems_fs_init_helper =
 #endif
 
 /*
+ * Scheduler configuration.
+ *
+ * The scheduler configuration allows an application to select the 
+ * scheduling policy to use.  The supported configurations are:
+ *  CONFIGURE_SCHEDULER_USER
+ *  CONFIGURE_SCHEDULER_PRIORITY
+ * 
+ * If no configuration is specified by the application, then 
+ * CONFIGURE_SCHEDULER_PRIORITY is assumed to be the default.
+ *
+ * An application can define its own scheduling policy by defining
+ * CONFIGURE_SCHEDULER_USER and CONFIGURE_SCHEDULER_ENTRY_USER to point
+ * to an initialization routine.  Note: CONFIGURE_SCHEDULER_USER is not 
+ * fully supported, since it has no per-thread field.
+ *
+ * To add a new scheduler:
+ */
+#include <rtems/score/scheduler.h>
+
+#if defined(CONFIGURE_SCHEDULER_USER) && \
+    !defined(CONFIGURE_SCHEDULER_ENTRY_USER)
+  #error "CONFIGURE_ERROR: CONFIGURE_SCHEDULER_USER without CONFIGURE_SCHEDULER_ENTRY_USER"
+#endif
+
+/* enable all RTEMS-provided schedulers */
+#if defined(CONFIGURE_SCHEDULER_ALL)
+  #define CONFIGURE_SCHEDULER_PRIORITY
+#endif
+
+/* If no scheduler is specified, the priority scheduler is default. */
+#if !defined(CONFIGURE_SCHEDULER_USER) && \
+    !defined(CONFIGURE_SCHEDULER_PRIORITY)
+  #define CONFIGURE_SCHEDULER_PRIORITY
+  #define CONFIGURE_SCHEDULER_POLICY _Scheduler_PRIORITY
+#endif
+
+/*
+ * If a user scheduler is specified and no policy is set, 
+ * the user scheduler is the default policy.
+ */
+#if defined(CONFIGURE_SCHEDULER_USER) && \
+    !defined(CONFIGURE_SCHEDULER_POLICY)
+  #define CONFIGURE_SCHEDULER_POLICY _Scheduler_USER
+#endif
+
+/* 
+ * Check for priority scheduler next, as it is the default policy if there
+ * is no CONFIGURE_SCHEDULER_POLICY set and no USER scheduler provided.
+ */
+#if defined(CONFIGURE_SCHEDULER_PRIORITY)
+  #include <rtems/score/schedulerpriority.h>
+  #define CONFIGURE_SCHEDULER_ENTRY_PRIORITY { _Scheduler_priority_Initialize }
+  #if !defined(CONFIGURE_SCHEDULER_POLICY)
+    #define CONFIGURE_SCHEDULER_POLICY _Scheduler_PRIORITY
+  #endif
+
+  /**
+   * define the memory used by the priority scheduler
+   */
+  #define CONFIGURE_MEMORY_SCHEDULER_PRIORITY ( \
+    _Configure_From_workspace( \
+      ((CONFIGURE_MAXIMUM_PRIORITY+1) * sizeof(Chain_Control)) ) \
+  )
+  #define CONFIGURE_MEMORY_PER_TASK_SCHEDULER_PRIORITY ( \
+    _Configure_From_workspace(sizeof(Scheduler_priority_Per_thread)) )
+#endif
+
+/* 
+ * Set up the scheduler table.  The scheduling code indexes this table to 
+ * invoke the correct scheduling implementation. The scheduler to use is 
+ * determined by the Configuration.scheduler_policy field, which is set
+ * by CONFIGURE_SCHEDULER_POLICY.  If a particular scheduler is not enabled,
+ * an empty entry is included in its entry in the scheduler table.
+ */
+
+  /**
+   * An empty scheduler entry
+   */
+  #define CONFIGURE_SCHEDULER_NULL { NULL }
+
+#ifdef CONFIGURE_INIT
+  /* the table of available schedulers. */
+  const Scheduler_Table_t _Scheduler_Table[] = {
+    #if defined(CONFIGURE_SCHEDULER_USER) && \
+        defined(CONFIGURE_SCHEDULER_ENTRY_USER)
+      CONFIGURE_SCHEDULER_ENTRY_USER,
+    #else
+      CONFIGURE_SCHEDULER_NULL,
+    #endif
+    #if defined(CONFIGURE_SCHEDULER_PRIORITY) && \
+        defined(CONFIGURE_SCHEDULER_ENTRY_PRIORITY)
+      CONFIGURE_SCHEDULER_ENTRY_PRIORITY,
+    #else
+      CONFIGURE_SCHEDULER_NULL,
+    #endif
+  };
+#endif
+
+/**
+ * Define the memory overhead for the scheduler
+ */
+#define CONFIGURE_MEMORY_FOR_SCHEDULER ( \
+    CONFIGURE_MEMORY_SCHEDULER_PRIORITY \
+  )
+
+#define CONFIGURE_MEMORY_PER_TASK_FOR_SCHEDULER ( \
+    CONFIGURE_MEMORY_PER_TASK_SCHEDULER_PRIORITY \
+  )
+
+/*
  *  If you said the IDLE task was going to do application initialization
  *  and didn't override the IDLE body, then something is amiss.
  */
@@ -1607,7 +1717,8 @@ rtems_fs_init_functions_t    rtems_fs_init_helper =
    (_Configure_From_workspace(CONFIGURE_MINIMUM_TASK_STACK_SIZE) + \
     CONFIGURE_MEMORY_PER_TASK_FOR_CLASSIC_API + \
     CONFIGURE_MEMORY_PER_TASK_FOR_NEWLIB + \
-    CONFIGURE_MEMORY_PER_TASK_FOR_POSIX_API))  + \
+    CONFIGURE_MEMORY_PER_TASK_FOR_POSIX_API + \
+    CONFIGURE_MEMORY_PER_TASK_FOR_SCHEDULER))  + \
   _Configure_From_workspace( \
     _Configure_Max_Objects(_number_FP_tasks) * CONTEXT_FP_SIZE) + \
   _Configure_From_workspace( \
@@ -1705,13 +1816,6 @@ rtems_fs_init_functions_t    rtems_fs_init_helper =
   _Configure_Object_RAM(1, sizeof(API_Mutex_Control))
 
 /**
- *  This defines the memory used by the thread ready chains.  There is
- *  one chain per priority.
- */
-#define CONFIGURE_MEMORY_FOR_THREAD_READY_CHAINS \
-    _Configure_From_workspace( \
-        ((CONFIGURE_MAXIMUM_PRIORITY+1) * sizeof(Chain_Control)) )
-/**
  *  This defines the amount of memory reserved for the IDLE task
  *  control structures and stack.
  */
@@ -1724,7 +1828,7 @@ rtems_fs_init_functions_t    rtems_fs_init_helper =
  */
 #define CONFIGURE_MEMORY_FOR_SYSTEM_OVERHEAD \
   ( CONFIGURE_MEMORY_FOR_IDLE_TASK +                /* IDLE and stack */ \
-    CONFIGURE_MEMORY_FOR_THREAD_READY_CHAINS +     /* Ready chains */ \
+    CONFIGURE_MEMORY_FOR_SCHEDULER +                /* Scheduler */ \
     CONFIGURE_INTERRUPT_VECTOR_TABLE +             /* interrupt vectors */ \
     CONFIGURE_INTERRUPT_STACK_MEMORY +             /* interrupt stack */ \
     CONFIGURE_API_MUTEX_MEMORY                     /* allocation mutex */ \
@@ -2005,6 +2109,7 @@ rtems_fs_init_functions_t    rtems_fs_init_helper =
     CONFIGURE_MAXIMUM_USER_EXTENSIONS,        /* maximum dynamic extensions */
     CONFIGURE_MICROSECONDS_PER_TICK,          /* microseconds per clock tick */
     CONFIGURE_TICKS_PER_TIMESLICE,            /* ticks per timeslice quantum */
+    CONFIGURE_SCHEDULER_POLICY,               /* scheduling policy */
     CONFIGURE_IDLE_TASK_BODY,                 /* user's IDLE task */
     CONFIGURE_IDLE_TASK_STACK_SIZE,           /* IDLE task stack size */
     CONFIGURE_INTERRUPT_STACK_SIZE,           /* interrupt stack size */
diff --git a/cpukit/sapi/include/rtems/config.h b/cpukit/sapi/include/rtems/config.h
index 1f9b56c3e8..541bc9ddff 100644
--- a/cpukit/sapi/include/rtems/config.h
+++ b/cpukit/sapi/include/rtems/config.h
@@ -118,6 +118,10 @@ typedef struct {
    */
   uint32_t                       ticks_per_timeslice;
 
+  /** This field specifies the scheduling policy to use.
+   */
+  uint32_t                       scheduler_policy;
+
   /** This element points to the BSP's optional idle task which may override
    *  the default one provided with RTEMS.
    */
diff --git a/cpukit/sapi/src/exinit.c b/cpukit/sapi/src/exinit.c
index 1185b74e4a..2cbddfa1da 100644
--- a/cpukit/sapi/src/exinit.c
+++ b/cpukit/sapi/src/exinit.c
@@ -42,7 +42,7 @@
 #include <rtems/score/mpci.h>
 #endif
 #include <rtems/score/priority.h>
-#include <rtems/score/prioritybitmap.h>
+#include <rtems/score/scheduler.h>
 #include <rtems/score/thread.h>
 #include <rtems/score/tod.h>
 #include <rtems/score/userext.h>
@@ -131,6 +131,8 @@ void rtems_initialize_data_structures(void)
 
   _Thread_Handler_initialization();
 
+  _Scheduler_Handler_initialization();
+
   #if defined(RTEMS_MULTIPROCESSING)
     _Objects_MP_Handler_initialization();
     _MPCI_Handler_initialization( RTEMS_TIMEOUT );
diff --git a/cpukit/score/Makefile.am b/cpukit/score/Makefile.am
index fd1f2a90e2..6ad13b51e8 100644
--- a/cpukit/score/Makefile.am
+++ b/cpukit/score/Makefile.am
@@ -26,6 +26,7 @@ include_rtems_score_HEADERS = include/rtems/score/address.h \
     include/rtems/score/interr.h include/rtems/score/isr.h \
     include/rtems/score/object.h include/rtems/score/percpu.h \
     include/rtems/score/priority.h include/rtems/score/prioritybitmap.h \
+    include/rtems/score/scheduler.h include/rtems/score/schedulerpriority.h \
     include/rtems/score/stack.h include/rtems/score/states.h \
     include/rtems/score/sysstate.h include/rtems/score/thread.h \
     include/rtems/score/threadq.h include/rtems/score/threadsync.h \
@@ -54,6 +55,7 @@ include_rtems_score_HEADERS += inline/rtems/score/address.inl \
     inline/rtems/score/coresem.inl inline/rtems/score/heap.inl \
     inline/rtems/score/isr.inl inline/rtems/score/object.inl \
     inline/rtems/score/priority.inl inline/rtems/score/prioritybitmap.inl \
+    inline/rtems/score/scheduler.inl inline/rtems/score/schedulerpriority.inl \
     inline/rtems/score/stack.inl inline/rtems/score/states.inl \
     inline/rtems/score/sysstate.inl inline/rtems/score/thread.inl \
     inline/rtems/score/threadq.inl inline/rtems/score/tod.inl \
@@ -137,6 +139,19 @@ libscore_a_SOURCES += src/objectallocate.c src/objectclose.c \
     src/objectgetinfo.c src/objectgetinfoid.c src/objectapimaximumclass.c \
     src/objectnamespaceremove.c
 
+## SCHEDULER_C_FILES
+libscore_a_SOURCES += src/scheduler.c
+
+## SCHEDULERPRIORITY_C_FILES
+libscore_a_SOURCES += src/schedulerpriority.c \
+											src/schedulerpriorityblock.c \
+                      src/schedulerprioritythreadschedulerallocate.c \
+                      src/schedulerprioritythreadschedulerfree.c \
+                      src/schedulerprioritythreadschedulerupdate.c \
+											src/schedulerpriorityschedule.c \
+											src/schedulerpriorityunblock.c \
+											src/schedulerpriorityyield.c
+
 ## PROTECTED_HEAP_C_FILES
 libscore_a_SOURCES += src/pheapallocate.c \
     src/pheapextend.c src/pheapfree.c src/pheapgetsize.c \
@@ -153,7 +168,7 @@ libscore_a_SOURCES += src/thread.c src/threadchangepriority.c \
     src/threadsetstate.c src/threadsettransient.c \
     src/threadstackallocate.c src/threadstackfree.c src/threadstart.c \
     src/threadstartmultitasking.c src/threadsuspend.c \
-    src/threadtickletimeslice.c src/threadyieldprocessor.c \
+    src/threadtickletimeslice.c \
     src/iterateoverthreads.c src/threadblockingoperationcancel.c
 
 ## THREADQ_C_FILES
diff --git a/cpukit/score/include/rtems/score/prioritybitmap.h b/cpukit/score/include/rtems/score/prioritybitmap.h
index cd712952b2..bba5b428b6 100644
--- a/cpukit/score/include/rtems/score/prioritybitmap.h
+++ b/cpukit/score/include/rtems/score/prioritybitmap.h
@@ -37,18 +37,17 @@ extern "C" {
 
 #include <rtems/score/priority.h>
 
+
 /* 
- * TODO: 
- * These should only be instantiated if using the bit map handler.  The 
- * logical place for this is in confdefs.h when a scheduler that uses the 
- * bit map handler is configured.
+ * The Priority_bit_map_Control variables are instantiated only 
+ * if using the bit map handler.
  */
 
 /**
  *  Each sixteen bit entry in this array is associated with one of
  *  the sixteen entries in the Priority Bit map.
  */
-SCORE_EXTERN volatile Priority_bit_map_Control _Priority_Major_bit_map;
+extern volatile Priority_bit_map_Control _Priority_Major_bit_map;
 
 /** Each bit in the Priority Bitmap indicates whether or not there are
  *  threads ready at a particular priority.  The mapping of
@@ -56,7 +55,7 @@ SCORE_EXTERN volatile Priority_bit_map_Control _Priority_Major_bit_map;
  *  dependent as is the value of each bit used to indicate that
  *  threads are ready at that priority.
  */
-SCORE_EXTERN Priority_bit_map_Control
+extern Priority_bit_map_Control
                _Priority_Bit_map[16] CPU_STRUCTURE_ALIGNMENT;
 
 /*
diff --git a/cpukit/score/include/rtems/score/scheduler.h b/cpukit/score/include/rtems/score/scheduler.h
new file mode 100644
index 0000000000..b0ac20917c
--- /dev/null
+++ b/cpukit/score/include/rtems/score/scheduler.h
@@ -0,0 +1,156 @@
+/**
+ *  @file  rtems/score/scheduler.h
+ *
+ *  This include file contains all the constants and structures associated
+ *  with the scheduler.
+ */
+
+/*
+ *  Copyright (C) 2010 Gedare Bloom.
+ *
+ *  The license and distribution terms for this file may be
+ *  found in the file LICENSE in this distribution or at
+ *  http://www.rtems.com/license/LICENSE.
+ *
+ *  $Id$
+ */
+
+#ifndef _RTEMS_SCORE_SCHEDULER_H
+#define _RTEMS_SCORE_SCHEDULER_H
+
+/**
+ *  @defgroup ScoreScheduler Scheduler Handler
+ *
+ *  This handler encapsulates functionality related to managing sets of threads
+ *  that are ready for execution.
+ */
+/**@{*/
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <rtems/score/percpu.h>
+#include <rtems/score/chain.h>
+#include <rtems/score/priority.h>
+#include <rtems/score/prioritybitmap.h>
+
+/* 
+ * These defines are used to set the scheduler_policy value. The values 
+ * must correspond directly with the order of the fields in the scheduler
+ * table (Scheduler_Table_t), because the Configuration.scheduler_policy 
+ * field is used to index the scheduler table.
+ */
+#define _Scheduler_USER     (0)
+#define _Scheduler_PRIORITY (1)
+
+typedef struct Scheduler_Control_struct Scheduler_Control;
+
+/*
+ * The Scheduler_Table_t type defines the scheduler initialization table, 
+ * which is set up by confdefs.h based on the user's choice of scheduler 
+ * policy.
+ */
+typedef struct {
+  void ( *scheduler_init )( Scheduler_Control * );
+} Scheduler_Table_t;
+
+/* instantiated and initialized in confdefs.h */
+extern const Scheduler_Table_t          _Scheduler_Table[]; 
+
+/**
+ * The following Scheduler_Per_thread_xxx structures are used to 
+ * hold per-thread data used by the scheduler.  Thread_Control->scheduler is a 
+ * union of pointers, one for each of the following structures.  The
+ * scheduler->xxx field points to an instantion of one of these structures, 
+ * which is allocated from the workspace during _Thread_Start.
+ */
+
+/**
+ * Per-thread data related to the _Scheduler_PRIORITY scheduling policy.
+ */
+typedef struct {
+  /** This field points to the Ready FIFO for this thread's priority. */
+  Chain_Control                        *ready_chain;
+
+  /** This field contains precalculated priority map indices. */
+  Priority_bit_map_Information          Priority_map;
+} Scheduler_priority_Per_thread;
+
+/**
+ * function jump table that holds pointers to the functions that 
+ * implement specific schedulers.
+ */
+typedef struct {
+  /** Implements the scheduling decision logic (policy). */
+  void ( *schedule ) ( Scheduler_Control * );
+
+  /** Voluntarily yields the processor per the scheduling policy. */
+  void ( *yield ) ( Scheduler_Control * );
+
+  /** Removes the given thread from scheduling decisions. */
+  void ( *block ) ( Scheduler_Control *, Thread_Control * );
+
+  /** Adds the given thread to scheduling decisions. */
+  void ( *unblock ) ( Scheduler_Control *, Thread_Control * );
+
+  /** allocates the scheduler field of the given thread */
+  void * ( *scheduler_allocate ) ( Scheduler_Control *, Thread_Control * );
+
+  /** frees the scheduler field of the given thread */
+  void ( *scheduler_free ) ( Scheduler_Control *, Thread_Control * );
+  
+  /** updates the scheduler field of the given thread -- primarily used 
+   * when changing the thread's priority. */
+  void ( *scheduler_update ) ( Scheduler_Control *, Thread_Control * );
+} Scheduler_Operations;
+
+/**
+ * This is the structure used to manage the scheduler.
+ */
+struct Scheduler_Control_struct {
+  /** 
+   *  This union contains the pointer to the data structure used to manage 
+   *  the ready set of tasks. The pointer varies based upon the type of 
+   *  ready queue required by the scheduler.
+   */
+  union {
+    /** 
+     * This is the set of lists (an array of Chain_Control) for 
+     * priority scheduling. 
+     */
+    Chain_Control            *Priority;
+
+  } ready_queues;
+
+  /** The jump table for scheduler-specific functions */
+  Scheduler_Operations                  operations;
+};
+
+/**
+ *  The _Scheduler holds the structures used to manage the
+ *  scheduler.
+ *
+ * @note Can we make this per-cpu? then _Scheduler will be a macro.
+ */
+SCORE_EXTERN Scheduler_Control          _Scheduler;
+
+/**
+ *  This routine initializes the scheduler to the policy chosen by the user 
+ *  through confdefs, or to the priority scheduler with ready chains by
+ *  default.
+ */
+void _Scheduler_Handler_initialization( void );
+
+#ifndef __RTEMS_APPLICATION__
+#include <rtems/score/scheduler.inl>
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+/**@}*/
+
+#endif
+/* end of include file */
diff --git a/cpukit/score/include/rtems/score/schedulerpriority.h b/cpukit/score/include/rtems/score/schedulerpriority.h
new file mode 100644
index 0000000000..54c999f058
--- /dev/null
+++ b/cpukit/score/include/rtems/score/schedulerpriority.h
@@ -0,0 +1,117 @@
+/**
+ *  @file  rtems/score/schedulerpriority.h
+ *
+ *  This include file contains all the constants and structures associated
+ *  with the manipulation of threads for the priority-based scheduler.
+ */
+
+/*
+ *  Copryight (c) 2010 Gedare Bloom.
+ *
+ *  The license and distribution terms for this file may be
+ *  found in the file LICENSE in this distribution or at
+ *  http://www.rtems.com/license/LICENSE.
+ *
+ *  $Id$
+ */
+
+#ifndef _RTEMS_SCORE_SCHEDULERPRIORITY_H
+#define _RTEMS_SCORE_SCHEDULERPRIORITY_H
+
+/**
+ *  @addtogroup ScoreScheduler
+ *
+ */
+/**@{*/
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <rtems/score/chain.h>
+#include <rtems/score/priority.h>
+#include <rtems/score/percpu.h>
+#include <rtems/score/scheduler.h>
+#include <rtems/score/wkspace.h>
+
+/**
+ * This routine initializes the priority scheduler.
+ */
+void _Scheduler_priority_Initialize(
+    Scheduler_Control    *the_scheduler
+);
+
+/**
+ *  This routine removes @a the_thread from the scheduling decision, 
+ *  that is, removes it from the ready queue.  It performs
+ *  any necessary scheduling operations including the selection of
+ *  a new heir thread.
+ */
+void _Scheduler_priority_Block( 
+    Scheduler_Control *the_scheduler,
+    Thread_Control    *the_thread 
+);
+
+/**
+ *  This kernel routine sets the heir thread to be the next ready thread 
+ *  by invoking the_scheduler->ready_queue->operations->first().
+ */
+void _Scheduler_priority_Schedule(
+    Scheduler_Control *the_scheduler
+);
+
+/**
+ * This routine allocates @a the_thread->scheduler.
+ */
+void * _Scheduler_priority_Thread_scheduler_allocate(
+    Scheduler_Control   *the_scheduler,
+    Thread_Control      *the_thread
+);
+
+/**
+ * This routine frees @a the_thread->scheduler.
+ */
+void _Scheduler_priority_Thread_scheduler_free(
+    Scheduler_Control   *the_scheduler,
+    Thread_Control      *the_thread
+);
+
+/**
+ * This routine updates @a the_thread->scheduler based on @a the_scheduler 
+ * structures and thread state
+ */
+void _Scheduler_priority_Thread_scheduler_update(
+    Scheduler_Control   *the_scheduler,
+    Thread_Control      *the_thread
+);
+
+/**
+ *  This routine adds @a the_thread to the scheduling decision, 
+ *  that is, adds it to the ready queue and 
+ *  updates any appropriate scheduling variables, for example the heir thread.
+ */
+void _Scheduler_priority_Unblock(
+    Scheduler_Control *the_scheduler,
+    Thread_Control    *the_thread 
+);
+
+/**
+ *  This routine is invoked when a thread wishes to voluntarily
+ *  transfer control of the processor to another thread in the queue.
+ */
+void _Scheduler_priority_Yield(
+    Scheduler_Control *the_scheduler
+);
+
+#ifndef __RTEMS_APPLICATION__
+#include <rtems/score/schedulerpriority.inl>
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+/**@}*/
+
+#endif
+/* end of include file */
diff --git a/cpukit/score/include/rtems/score/thread.h b/cpukit/score/include/rtems/score/thread.h
index 9565458bb8..370d5491a3 100644
--- a/cpukit/score/include/rtems/score/thread.h
+++ b/cpukit/score/include/rtems/score/thread.h
@@ -70,7 +70,7 @@ extern "C" {
 #endif
 #include <rtems/score/object.h>
 #include <rtems/score/priority.h>
-#include <rtems/score/prioritybitmap.h>
+#include <rtems/score/scheduler.h>
 #include <rtems/score/stack.h>
 #include <rtems/score/states.h>
 #include <rtems/score/tod.h>
@@ -390,10 +390,10 @@ struct Thread_Control_struct {
    *  since it was created.
    */
   Thread_CPU_usage_t                    cpu_time_used;
-  /** This field points to the Ready FIFO for this priority. */
-  Chain_Control                        *ready;
-  /** This field contains precalculated priority map indices. */
-  Priority_bit_map_Information          Priority_map;
+  /** This union holds per-thread data for the scheduler and ready queue. */
+  union {
+    Scheduler_priority_Per_thread      *priority;
+  } scheduler;
   /** This field contains information about the starting state of
    *  this thread.
    */
@@ -456,12 +456,6 @@ SCORE_EXTERN uint32_t   _Thread_Maximum_extensions;
 SCORE_EXTERN uint32_t   _Thread_Ticks_per_timeslice;
 
 /**
- *  The following points to the array of FIFOs used to manage the
- *  set of ready threads.
- */
-SCORE_EXTERN Chain_Control *_Thread_Ready_chain;
-
-/**
  *  The following points to the thread whose floating point
  *  context is currently loaded.
  */
@@ -654,13 +648,6 @@ void _Thread_Set_transient(
 void _Thread_Tickle_timeslice( void );
 
 /**
- *  This routine is invoked when a thread wishes to voluntarily
- *  transfer control of the processor to another thread of equal
- *  or greater priority.
- */
-void _Thread_Yield_processor( void );
-
-/**
  *  This routine initializes the context of the_thread to its
  *  appropriate starting state.
  */
diff --git a/cpukit/score/inline/rtems/score/scheduler.inl b/cpukit/score/inline/rtems/score/scheduler.inl
new file mode 100644
index 0000000000..4a0f10a3f3
--- /dev/null
+++ b/cpukit/score/inline/rtems/score/scheduler.inl
@@ -0,0 +1,139 @@
+/** 
+ *  @file  rtems/score/scheduler.inl
+ *
+ *  This inline file contains all of the inlined routines associated with
+ *  the manipulation of the scheduler.
+ */
+
+/*
+ *  Copyright (C) 2010 Gedare Bloom.
+ *
+ *  The license and distribution terms for this file may be
+ *  found in the file LICENSE in this distribution or at
+ *  http://www.rtems.com/license/LICENSE.
+ *
+ *  $Id$
+ */
+
+#ifndef _RTEMS_SCORE_SCHEDULER_H
+# error "Never use <rtems/score/scheduler.inl> directly; include <rtems/score/scheduler.h> instead."
+#endif
+
+#ifndef _RTEMS_SCORE_SCHEDULER_INL
+#define _RTEMS_SCORE_SCHEDULER_INL
+
+/**
+ *  @addtogroup ScoreScheduler
+ * @{
+ */
+
+/**
+ * The preferred method to add a new scheduler is to define the jump table 
+ * entries and add a case to the _Scheduler_Initialize routine. 
+ *
+ * Generic scheduling implementations that rely on the ready queue only can 
+ * be found in the _Scheduler_queue_XXX functions.
+ *
+ */
+
+/* Passing the Scheduler_Control* to these functions allows for multiple 
+ * scheduler's to exist simultaneously, which could be useful on an SMP 
+ * system.  Then remote Schedulers may be accessible.  How to protect such 
+ * accesses remains an open problem.
+ */
+
+/** @brief _Scheduler_Schedule
+ *
+ *  This kernel routine implements the scheduling decision logic for 
+ *  @a the_scheduler. It does NOT dispatch.
+ */
+RTEMS_INLINE_ROUTINE void _Scheduler_Schedule(
+    Scheduler_Control *the_scheduler 
+)
+{
+  the_scheduler->operations.schedule( the_scheduler );
+}
+
+/** @brief _Scheduler_Yield
+ *
+ *  This routine is invoked when a thread wishes to voluntarily
+ *  transfer control of the processor to another thread. This routine
+ *  always operates on the scheduler that 'owns' the currently executing
+ *  thread.
+ */
+RTEMS_INLINE_ROUTINE void _Scheduler_Yield( void )
+{
+  _Scheduler.operations.yield( &_Scheduler );
+}
+
+/** @brief _Scheduler_Block
+ *
+ *  This routine removes @a the_thread from the scheduling decision for 
+ *  @a the_scheduler. The primary task is to remove the thread from the 
+ *  ready queue.  It performs any necessary schedulering operations 
+ *  including the selection of a new heir thread.
+ */
+RTEMS_INLINE_ROUTINE void _Scheduler_Block( 
+    Scheduler_Control *the_scheduler,
+    Thread_Control    *the_thread 
+)
+{
+  the_scheduler->operations.block( the_scheduler, the_thread );
+}
+
+/** @brief _Scheduler_Unblock
+ *
+ *  This routine adds @a the_thread to the scheduling decision for 
+ *  @a the_scheduler.  The primary task is to add the thread to the
+ *  ready queue per the schedulering policy and update any appropriate 
+ *  scheduling variables, for example the heir thread.
+ */
+RTEMS_INLINE_ROUTINE void _Scheduler_Unblock(
+    Scheduler_Control *the_scheduler,
+    Thread_Control    *the_thread 
+)
+{
+  the_scheduler->operations.unblock( the_scheduler, the_thread );
+}
+
+/** @brief _Scheduler_Thread_scheduler_allocate
+ *
+ * This routine allocates @a the_thread->scheduler
+ */
+RTEMS_INLINE_ROUTINE void* _Scheduler_Thread_scheduler_allocate( 
+  Scheduler_Control *the_scheduler,
+  Thread_Control    *the_thread
+)
+{
+  return 
+    the_scheduler->operations.scheduler_allocate( the_scheduler, the_thread );
+}
+
+/** @brief _Scheduler_Thread_scheduler_free
+ *
+ * This routine frees @a the_thread->scheduler
+ */
+RTEMS_INLINE_ROUTINE void _Scheduler_Thread_scheduler_free( 
+  Scheduler_Control *the_scheduler,
+  Thread_Control    *the_thread
+)
+{
+  return the_scheduler->operations.scheduler_free( the_scheduler, the_thread );
+}
+
+/** @brief _Scheduler_Thread_scheduler_update
+ *
+ * This routine updates @a the_thread->scheduler
+ */
+RTEMS_INLINE_ROUTINE void _Scheduler_Thread_scheduler_update( 
+  Scheduler_Control *the_scheduler,
+  Thread_Control    *the_thread
+)
+{
+  the_scheduler->operations.scheduler_update( the_scheduler, the_thread );
+}
+
+/**@}*/
+
+#endif
+/* end of include file */
diff --git a/cpukit/score/inline/rtems/score/schedulerpriority.inl b/cpukit/score/inline/rtems/score/schedulerpriority.inl
new file mode 100644
index 0000000000..da6de2802d
--- /dev/null
+++ b/cpukit/score/inline/rtems/score/schedulerpriority.inl
@@ -0,0 +1,286 @@
+/** 
+ *  @file  rtems/score/schedulerpriority.inl
+ *
+ *  This inline file contains all of the inlined routines associated with
+ *  the manipulation of the priority-based scheduling structures.
+ */
+
+/*
+ *  Copyright (C) 2010 Gedare Bloom.
+ *
+ *  The license and distribution terms for this file may be
+ *  found in the file LICENSE in this distribution or at
+ *  http://www.rtems.com/license/LICENSE.
+ *
+ *  $Id$
+ */
+
+#ifndef _RTEMS_SCORE_SCHEDULERPRIORITY_H
+# error "Never use <rtems/score/schedulerpriority.inl> directly; include <rtems/score/schedulerpriority.h> instead."
+#endif
+
+#ifndef _RTEMS_SCORE_SCHEDULERPRIORITY_INL
+#define _RTEMS_SCORE_SCHEDULERPRIORITY_INL
+
+/**
+ *  @addtogroup ScoreScheduler
+ * @{
+ */
+
+/** @brief  Scheduler priority Ready queue initialize
+ *
+ *  This routine initializes @a the_ready_queue for priority-based scheduling.
+ */
+RTEMS_INLINE_ROUTINE void _Scheduler_priority_Ready_queue_initialize(
+  Scheduler_Control         *the_scheduler
+) {
+  uint32_t index;
+
+  /* allocate ready queue structures */
+  the_scheduler->ready_queues.Priority = (Chain_Control *) 
+    _Workspace_Allocate_or_fatal_error(
+      (PRIORITY_MAXIMUM + 1) * sizeof(Chain_Control)
+    );
+
+  /* initialize ready queue structures */
+  for( index=0; index <= PRIORITY_MAXIMUM; index++)
+    _Chain_Initialize_empty( &the_scheduler->ready_queues.Priority[index] );
+}
+
+/* 
+ *  _Scheduler_priority_Ready_queue_enqueue
+ *
+ *  This routine puts @a the_thread on to the priority-based ready queue.
+ *  
+ *  Input parameters:
+ *    the_thread  - pointer to thread
+ *
+ *  Output parameters: NONE
+ *
+ *  INTERRUPT LATENCY:
+ */
+
+RTEMS_INLINE_ROUTINE void _Scheduler_priority_Ready_queue_enqueue(
+  Thread_Control                  *the_thread
+)
+{
+  _Priority_bit_map_Add( &the_thread->scheduler.priority->Priority_map );
+  
+  _Chain_Append_unprotected( the_thread->scheduler.priority->ready_chain, 
+      &the_thread->Object.Node );
+}
+
+/*
+ *  _Scheduler_priority_Ready_queue_Enqueue_first
+ *
+ *  This routine puts @a the_thread to the head of the ready queue. 
+ *  For priority-based ready queues, the thread will be the first thread
+ *  at its priority level.
+ *  
+ *  Input parameters:
+ *    the_thread      - pointer to thread
+ *
+ *  Output parameters: NONE
+ *
+ *  INTERRUPT LATENCY:
+ */
+
+RTEMS_INLINE_ROUTINE void _Scheduler_priority_Ready_queue_enqueue_first(
+  Thread_Control                   *the_thread
+)
+{
+  _Priority_bit_map_Add( &the_thread->scheduler.priority->Priority_map );
+
+  _Chain_Prepend_unprotected( the_thread->scheduler.priority->ready_chain, 
+      &the_thread->Object.Node );
+}
+
+/*
+ *  _Scheduler_priority_Ready_queue_extract
+ *
+ *  This routine removes a specific thread from the specified 
+ *  priority-based ready queue.
+ *
+ *  Input parameters:
+ *    the_thread       - pointer to a thread control block
+ *
+ *  Output parameters: NONE
+ *
+ *  INTERRUPT LATENCY: NONE
+ */
+
+RTEMS_INLINE_ROUTINE void _Scheduler_priority_Ready_queue_extract(
+  Thread_Control        *the_thread
+)
+{
+  Chain_Control         *ready  = the_thread->scheduler.priority->ready_chain;
+
+  if ( _Chain_Has_only_one_node( ready ) ) {
+    _Chain_Initialize_empty( ready );
+    _Priority_bit_map_Remove( &the_thread->scheduler.priority->Priority_map );
+  } else
+    _Chain_Extract_unprotected( &the_thread->Object.Node );
+}
+
+/*
+ *  _Scheduler_priority_Ready_queue_first
+ *
+ *  This routines returns a pointer to the first thread on @a the_ready_queue.
+ *
+ *  Input parameters:
+ *    the_ready_queue - pointer to thread queue
+ *
+ *  Output parameters:
+ *    returns - first thread or NULL
+ */
+
+RTEMS_INLINE_ROUTINE Thread_Control *_Scheduler_priority_Ready_queue_first(
+  Chain_Control       *the_ready_queue
+)
+{
+  uint32_t    index = _Priority_bit_map_Get_highest();
+
+  if ( !_Chain_Is_empty( &the_ready_queue[ index ] ) )
+    return (Thread_Control *) the_ready_queue[ index ].first;
+
+  return NULL;
+}
+
+/*
+ *  _Scheduler_priority_Ready_queue_requeue
+ *
+ *  This routine is invoked when a thread changes priority and should be
+ *  moved to a different position on the ready queue.
+ *
+ *  Input parameters:
+ *    the_thread        - pointer to a thread control block
+ *
+ *  Output parameters: NONE
+ *
+ *  INTERRUPT LATENCY: NONE
+ */
+
+RTEMS_INLINE_ROUTINE void _Scheduler_priority_Ready_queue_requeue(
+  Thread_Control            *the_thread
+)
+{
+  if ( !_Chain_Has_only_one_node(
+        the_thread->scheduler.priority->ready_chain
+        ) ) {
+    _Chain_Extract_unprotected( &the_thread->Object.Node );
+
+    _Chain_Append_unprotected( the_thread->scheduler.priority->ready_chain, 
+      &the_thread->Object.Node );
+  }
+}
+
+/*
+ * _Scheduler_priority_Schedule_body
+ *
+ * This kernel routine implements scheduling decision logic for priority-based
+ * scheduling.  
+ *
+ * Input parameters:
+ *   the_scheduler  - pointer to scheduler control
+ *   the_thread     - pointer to thread control block
+ *
+ * Output parameters:  NONE
+ *
+ *  INTERRUPT LATENCY:
+ */
+
+RTEMS_INLINE_ROUTINE void _Scheduler_priority_Schedule_body(
+  Scheduler_Control     *the_scheduler
+)
+{
+  _Thread_Heir = _Scheduler_priority_Ready_queue_first(
+      the_scheduler->ready_queues.Priority
+  );
+}
+
+/*
+ * _Scheduler_priority_Block_body
+ *
+ * This kernel routine removes the_thread from scheduling decisions based 
+ * on simple queue extraction.
+ *
+ * Input parameters:
+ *   the_scheduler  - pointer to scheduler control
+ *   the_thread     - pointer to thread control block
+ *
+ * Output parameters:  NONE
+ *
+ *  INTERRUPT LATENCY:
+ */
+
+RTEMS_INLINE_ROUTINE void _Scheduler_priority_Block_body(
+  Scheduler_Control *the_scheduler,
+  Thread_Control   *the_thread
+)
+{
+  _Scheduler_priority_Ready_queue_extract(the_thread);
+
+  /* TODO: flash critical section */
+
+  if ( _Thread_Is_heir( the_thread ) )
+     _Scheduler_priority_Schedule_body(the_scheduler);
+
+  if ( _Thread_Is_executing( the_thread ) )
+    _Thread_Dispatch_necessary = true;
+
+  return;
+}
+
+/*
+ *  _Scheduler_priority_Unblock_body
+ *
+ *  This kernel routine readies the requested thread according to the queuing 
+ *  discipline. A new heir thread may be selected.
+ *
+ *  Input parameters:
+ *    the_scheduler - pointer to scheduler control
+ *    the_thread    - pointer to thread control block
+ *
+ *  Output parameters:  NONE
+ *
+ *  NOTE:  This routine uses the "blocking" heir selection mechanism.
+ *         This ensures the correct heir after a thread restart.
+ *
+ *  INTERRUPT LATENCY:
+ */
+
+RTEMS_INLINE_ROUTINE void _Scheduler_priority_Unblock_body (
+  Scheduler_Control       *the_scheduler,
+  Thread_Control          *the_thread
+)
+{
+  _Scheduler_priority_Ready_queue_enqueue(
+      the_thread
+  );
+
+  /* TODO: flash critical section */
+
+  /*
+   *  If the thread that was unblocked is more important than the heir,
+   *  then we have a new heir.  This may or may not result in a
+   *  context switch.
+   *
+   *  Normal case:
+   *    If the current thread is preemptible, then we need to do
+   *    a context switch.
+   *  Pseudo-ISR case:
+   *    Even if the thread isn't preemptible, if the new heir is
+   *    a pseudo-ISR system task, we need to do a context switch.
+   */
+  if ( the_thread->current_priority < _Thread_Heir->current_priority ) {
+    _Thread_Heir = the_thread;
+    if ( _Thread_Executing->is_preemptible ||
+        the_thread->current_priority == 0 )
+      _Thread_Dispatch_necessary = true;
+  }
+}
+
+/**@}*/
+
+#endif
+/* end of include file */
diff --git a/cpukit/score/inline/rtems/score/thread.inl b/cpukit/score/inline/rtems/score/thread.inl
index d0a9e703f7..e700bdfb53 100644
--- a/cpukit/score/inline/rtems/score/thread.inl
+++ b/cpukit/score/inline/rtems/score/thread.inl
@@ -120,17 +120,6 @@ RTEMS_INLINE_ROUTINE void _Thread_Restart_self( void )
 }
 
 /**
- *  This function returns a pointer to the highest priority
- *  ready thread.
- */
-
-RTEMS_INLINE_ROUTINE void _Thread_Calculate_heir( void )
-{
-  _Thread_Heir = (Thread_Control *)
-    _Thread_Ready_chain[ _Priority_bit_map_Get_highest() ].first;
-}
-
-/**
  *  This function returns true if the floating point context of
  *  the_thread is currently loaded in the floating point unit, and
  *  false otherwise.
diff --git a/cpukit/score/preinstall.am b/cpukit/score/preinstall.am
index 9768f8c81d..65f28c4a85 100644
--- a/cpukit/score/preinstall.am
+++ b/cpukit/score/preinstall.am
@@ -111,6 +111,14 @@ $(PROJECT_INCLUDE)/rtems/score/prioritybitmap.h: include/rtems/score/prioritybit
 	$(INSTALL_DATA) $< $(PROJECT_INCLUDE)/rtems/score/prioritybitmap.h
 PREINSTALL_FILES += $(PROJECT_INCLUDE)/rtems/score/prioritybitmap.h
 
+$(PROJECT_INCLUDE)/rtems/score/scheduler.h: include/rtems/score/scheduler.h $(PROJECT_INCLUDE)/rtems/score/$(dirstamp)
+	$(INSTALL_DATA) $< $(PROJECT_INCLUDE)/rtems/score/scheduler.h
+PREINSTALL_FILES += $(PROJECT_INCLUDE)/rtems/score/scheduler.h
+
+$(PROJECT_INCLUDE)/rtems/score/schedulerpriority.h: include/rtems/score/schedulerpriority.h $(PROJECT_INCLUDE)/rtems/score/$(dirstamp)
+	$(INSTALL_DATA) $< $(PROJECT_INCLUDE)/rtems/score/schedulerpriority.h
+PREINSTALL_FILES += $(PROJECT_INCLUDE)/rtems/score/schedulerpriority.h
+
 $(PROJECT_INCLUDE)/rtems/score/stack.h: include/rtems/score/stack.h $(PROJECT_INCLUDE)/rtems/score/$(dirstamp)
 	$(INSTALL_DATA) $< $(PROJECT_INCLUDE)/rtems/score/stack.h
 PREINSTALL_FILES += $(PROJECT_INCLUDE)/rtems/score/stack.h
@@ -245,6 +253,14 @@ $(PROJECT_INCLUDE)/rtems/score/prioritybitmap.inl: inline/rtems/score/prioritybi
 	$(INSTALL_DATA) $< $(PROJECT_INCLUDE)/rtems/score/prioritybitmap.inl
 PREINSTALL_FILES += $(PROJECT_INCLUDE)/rtems/score/prioritybitmap.inl
 
+$(PROJECT_INCLUDE)/rtems/score/scheduler.inl: inline/rtems/score/scheduler.inl $(PROJECT_INCLUDE)/rtems/score/$(dirstamp)
+	$(INSTALL_DATA) $< $(PROJECT_INCLUDE)/rtems/score/scheduler.inl
+PREINSTALL_FILES += $(PROJECT_INCLUDE)/rtems/score/scheduler.inl
+
+$(PROJECT_INCLUDE)/rtems/score/schedulerpriority.inl: inline/rtems/score/schedulerpriority.inl $(PROJECT_INCLUDE)/rtems/score/$(dirstamp)
+	$(INSTALL_DATA) $< $(PROJECT_INCLUDE)/rtems/score/schedulerpriority.inl
+PREINSTALL_FILES += $(PROJECT_INCLUDE)/rtems/score/schedulerpriority.inl
+
 $(PROJECT_INCLUDE)/rtems/score/stack.inl: inline/rtems/score/stack.inl $(PROJECT_INCLUDE)/rtems/score/$(dirstamp)
 	$(INSTALL_DATA) $< $(PROJECT_INCLUDE)/rtems/score/stack.inl
 PREINSTALL_FILES += $(PROJECT_INCLUDE)/rtems/score/stack.inl
diff --git a/cpukit/score/src/scheduler.c b/cpukit/score/src/scheduler.c
new file mode 100644
index 0000000000..9d7424eef6
--- /dev/null
+++ b/cpukit/score/src/scheduler.c
@@ -0,0 +1,45 @@
+/*
+ *  Scheduler Handler
+ *
+ *  Copyright (C) 2010 Gedare Bloom.
+ *
+ *  The license and distribution terms for this file may be
+ *  found in the file LICENSE in this distribution or at
+ *  http://www.rtems.com/license/LICENSE.
+ *
+ *  $Id$
+ */
+
+#if HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <rtems/system.h>
+#include <rtems/config.h>
+#include <rtems/score/chain.h>
+#include <rtems/score/isr.h>
+#include <rtems/score/object.h>
+#include <rtems/score/scheduler.h>
+#include <rtems/score/schedulerpriority.h>
+#include <rtems/score/states.h>
+#include <rtems/score/thread.h>
+
+/*
+ *  _Scheduler_Handler_initialization
+ *
+ *  This routine initializes the scheduler by calling the scheduler_init 
+ *  function registered in the Configuration Scheduler Table.
+ *
+ *  Input parameters: NONE
+ *
+ *  Output parameters: NONE
+ */
+
+void _Scheduler_Handler_initialization( )
+{
+  Scheduler_Control *the_scheduler = &_Scheduler;
+
+  (*(_Scheduler_Table[Configuration.scheduler_policy].scheduler_init))(
+      the_scheduler
+  );
+}
diff --git a/cpukit/score/src/schedulerpriority.c b/cpukit/score/src/schedulerpriority.c
new file mode 100644
index 0000000000..5e7ad61d9a
--- /dev/null
+++ b/cpukit/score/src/schedulerpriority.c
@@ -0,0 +1,66 @@
+/*
+ *  Scheduler Handler
+ *
+ *  Copyright (C) 2010 Gedare Bloom.
+ *
+ *  The license and distribution terms for this file may be
+ *  found in the file LICENSE in this distribution or at
+ *  http://www.rtems.com/license/LICENSE.
+ *
+ *  $Id$
+ */
+
+#if HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <rtems/system.h>
+#include <rtems/config.h>
+#include <rtems/score/chain.h>
+#include <rtems/score/isr.h>
+#include <rtems/score/object.h>
+#include <rtems/score/scheduler.h>
+#include <rtems/score/schedulerpriority.h>
+#include <rtems/score/states.h>
+#include <rtems/score/thread.h>
+
+/* Instantiate any global variables needed by the priority scheduler */
+volatile Priority_bit_map_Control _Priority_Major_bit_map;
+
+Priority_bit_map_Control          _Priority_Bit_map[16] CPU_STRUCTURE_ALIGNMENT;
+
+/*
+ *  _Scheduler_priority_Initialize
+ *
+ * Initializes the scheduler for priority scheduling.
+ *
+ *  Input parameters:
+ *    the_scheduler - pointer to scheduler control
+ *
+ *  Output parameters: NONE
+ */
+
+void _Scheduler_priority_Initialize (
+    Scheduler_Control       *the_scheduler
+)
+{
+  /* the operations table is a jump table to redirect generic scheduler 
+   * function calls to scheduler implementation specific functions.  The 
+   * main purpose of scheduler initialization is to set up the jump table 
+   * for the scheduler.  Every scheduler implementation provides its own
+   * scheduler operations table.
+   */
+  the_scheduler->operations.schedule           = &_Scheduler_priority_Schedule;
+  the_scheduler->operations.yield              = &_Scheduler_priority_Yield;
+  the_scheduler->operations.block              = &_Scheduler_priority_Block;
+  the_scheduler->operations.unblock            = &_Scheduler_priority_Unblock;
+  the_scheduler->operations.scheduler_allocate = 
+      &_Scheduler_priority_Thread_scheduler_allocate;
+  the_scheduler->operations.scheduler_free     = 
+      &_Scheduler_priority_Thread_scheduler_free;
+  the_scheduler->operations.scheduler_update   = 
+      &_Scheduler_priority_Thread_scheduler_update;
+
+  _Scheduler_priority_Ready_queue_initialize( the_scheduler );
+  _Priority_bit_map_Handler_initialization( );
+}
diff --git a/cpukit/score/src/schedulerpriorityblock.c b/cpukit/score/src/schedulerpriorityblock.c
new file mode 100644
index 0000000000..cc137e64f5
--- /dev/null
+++ b/cpukit/score/src/schedulerpriorityblock.c
@@ -0,0 +1,48 @@
+/*
+ *  Scheduler Handler
+ *
+ *  Copyright (C) 2010 Gedare Bloom.
+ *
+ *  The license and distribution terms for this file may be
+ *  found in found in the file LICENSE in this distribution or at
+ *  http://www.rtems.com/license/LICENSE.
+ *
+ *  $Id$
+ */
+
+#if HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <rtems/system.h>
+#include <rtems/score/context.h>
+#include <rtems/score/interr.h>
+#include <rtems/score/isr.h>
+#include <rtems/score/object.h>
+#include <rtems/score/priority.h>
+#include <rtems/score/scheduler.h>
+#include <rtems/score/schedulerpriority.h>
+#include <rtems/score/thread.h>
+
+/*
+ * _Scheduler_priority_Block
+ *
+ * This kernel routine removes the_thread from scheduling decisions based 
+ * on simple queue extraction.
+ *
+ * Input parameters:
+ *   the_scheduler  - pointer to scheduler control
+ *   the_thread     - pointer to thread control block
+ *
+ * Output parameters:  NONE
+ *
+ *  INTERRUPT LATENCY:
+ */
+
+void _Scheduler_priority_Block(
+  Scheduler_Control *the_scheduler,
+  Thread_Control   *the_thread
+)
+{
+  _Scheduler_priority_Block_body(the_scheduler, the_thread);
+}
diff --git a/cpukit/score/src/schedulerpriorityschedule.c b/cpukit/score/src/schedulerpriorityschedule.c
new file mode 100644
index 0000000000..10c46652ef
--- /dev/null
+++ b/cpukit/score/src/schedulerpriorityschedule.c
@@ -0,0 +1,48 @@
+/*
+ *  Scheduler Handler
+ *
+ *  Copyright (C) 2010 Gedare Bloom.
+ *
+ *  The license and distribution terms for this file may be
+ *  found in found in the file LICENSE in this distribution or at
+ *  http://www.rtems.com/license/LICENSE.
+ *
+ *  $Id$
+ */
+
+#if HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <rtems/system.h>
+#include <rtems/score/context.h>
+#include <rtems/score/interr.h>
+#include <rtems/score/isr.h>
+#include <rtems/score/object.h>
+#include <rtems/score/priority.h>
+#include <rtems/score/percpu.h>
+#include <rtems/score/scheduler.h>
+#include <rtems/score/schedulerpriority.h>
+#include <rtems/score/thread.h>
+
+/*
+ * _Scheduler_priority_Schedule
+ *
+ * This kernel routine implements scheduling decision logic for priority-based
+ * scheduling.  
+ *
+ * Input parameters:
+ *   the_scheduler  - pointer to scheduler control
+ *   the_thread     - pointer to thread control block
+ *
+ * Output parameters:  NONE
+ *
+ *  INTERRUPT LATENCY:
+ */
+
+void _Scheduler_priority_Schedule(
+  Scheduler_Control     *the_scheduler
+)
+{
+  _Scheduler_priority_Schedule_body( the_scheduler );
+}
diff --git a/cpukit/score/src/schedulerprioritythreadschedulerallocate.c b/cpukit/score/src/schedulerprioritythreadschedulerallocate.c
new file mode 100644
index 0000000000..21595ff778
--- /dev/null
+++ b/cpukit/score/src/schedulerprioritythreadschedulerallocate.c
@@ -0,0 +1,53 @@
+/*
+ *  Scheduler Handler
+ *
+ *  Copyright (C) 2010 Gedare Bloom.
+ *
+ *  The license and distribution terms for this file may be
+ *  found in the file LICENSE in this distribution or at
+ *  http://www.rtems.com/license/LICENSE.
+ *
+ *  $Id$
+ */
+
+#if HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <rtems/system.h>
+#include <rtems/config.h>
+#include <rtems/score/chain.h>
+#include <rtems/score/isr.h>
+#include <rtems/score/object.h>
+#include <rtems/score/scheduler.h>
+#include <rtems/score/schedulerpriority.h>
+#include <rtems/score/states.h>
+#include <rtems/score/thread.h>
+#include <rtems/score/wkspace.h>
+
+/*
+ *  _Scheduler_priority_Thread_scheduler_allocate
+ *
+ * Allocates @a the_thread->scheduler
+ *
+ *  Input parameters:
+ *    the_scheduler - pointer to scheduler control
+ *    the_thread    - pointer to thread control block
+ *
+ *  Output parameters: 
+ *    Returns pointer to allocated space.
+ */
+
+void* _Scheduler_priority_Thread_scheduler_allocate (
+  Scheduler_Control     *the_scheduler,
+  Thread_Control        *the_thread
+)
+{
+  void                  *sched;
+
+  sched = _Workspace_Allocate( sizeof(Scheduler_priority_Per_thread) );
+
+  the_thread->scheduler.priority = (Scheduler_priority_Per_thread*) sched;
+
+  return sched;
+}
diff --git a/cpukit/score/src/schedulerprioritythreadschedulerfree.c b/cpukit/score/src/schedulerprioritythreadschedulerfree.c
new file mode 100644
index 0000000000..78226b5fb3
--- /dev/null
+++ b/cpukit/score/src/schedulerprioritythreadschedulerfree.c
@@ -0,0 +1,46 @@
+/*
+ *  Scheduler Handler
+ *
+ *  Copyright (C) 2010 Gedare Bloom.
+ *
+ *  The license and distribution terms for this file may be
+ *  found in the file LICENSE in this distribution or at
+ *  http://www.rtems.com/license/LICENSE.
+ *
+ *  $Id$
+ */
+
+#if HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <rtems/system.h>
+#include <rtems/config.h>
+#include <rtems/score/chain.h>
+#include <rtems/score/isr.h>
+#include <rtems/score/object.h>
+#include <rtems/score/scheduler.h>
+#include <rtems/score/schedulerpriority.h>
+#include <rtems/score/states.h>
+#include <rtems/score/thread.h>
+#include <rtems/score/wkspace.h>
+
+/*
+ *  _Scheduler_priority_Thread_scheduler_free
+ *
+ * Frees @a the_thread->scheduler
+ *
+ *  Input parameters:
+ *    the_scheduler - pointer to scheduler control
+ *    the_thread    - pointer to thread control block
+ *
+ *  Output parameters: NONE
+ */
+
+void _Scheduler_priority_Thread_scheduler_free (
+    Scheduler_Control *the_scheduler,
+    Thread_Control    *the_thread
+)
+{
+  _Workspace_Free( the_thread->scheduler.priority );
+}
diff --git a/cpukit/score/src/schedulerprioritythreadschedulerupdate.c b/cpukit/score/src/schedulerprioritythreadschedulerupdate.c
new file mode 100644
index 0000000000..c4c7e815ce
--- /dev/null
+++ b/cpukit/score/src/schedulerprioritythreadschedulerupdate.c
@@ -0,0 +1,55 @@
+/*
+ *  Scheduler Handler
+ *
+ *  Copyright (C) 2010 Gedare Bloom.
+ *
+ *  The license and distribution terms for this file may be
+ *  found in the file LICENSE in this distribution or at
+ *  http://www.rtems.com/license/LICENSE.
+ *
+ *  $Id$
+ */
+
+#if HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <rtems/system.h>
+#include <rtems/config.h>
+#include <rtems/score/chain.h>
+#include <rtems/score/isr.h>
+#include <rtems/score/object.h>
+#include <rtems/score/priority.h>
+#include <rtems/score/prioritybitmap.h>
+#include <rtems/score/scheduler.h>
+#include <rtems/score/schedulerpriority.h>
+#include <rtems/score/states.h>
+#include <rtems/score/thread.h>
+
+/*
+ *  _Scheduler_priority_Thread_scheduler_update
+ *
+ * Updates @a the_thread->scheduler
+ *
+ *  Input parameters:
+ *    the_scheduler - pointer to scheduler control
+ *    the_thread    - pointer to thread control block
+ *
+ *  Output parameters: NONE
+ */
+
+void _Scheduler_priority_Thread_scheduler_update (
+    Scheduler_Control *the_scheduler,
+    Thread_Control    *the_thread
+)
+{
+  Chain_Control *rq = the_scheduler->ready_queues.Priority;
+  the_thread->scheduler.priority->ready_chain = &rq[
+    the_thread->current_priority 
+  ];
+
+  _Priority_bit_map_Initialize_information( 
+      &the_thread->scheduler.priority->Priority_map, 
+      the_thread->current_priority 
+  );
+}
diff --git a/cpukit/score/src/schedulerpriorityunblock.c b/cpukit/score/src/schedulerpriorityunblock.c
new file mode 100644
index 0000000000..9030c0a137
--- /dev/null
+++ b/cpukit/score/src/schedulerpriorityunblock.c
@@ -0,0 +1,57 @@
+/*
+ *  Scheduler Handler
+ *
+ *  Copyright (C) 2010 Gedare Bloom.
+ *
+ *  The license and distribution terms for this file may be
+ *  found in found in the file LICENSE in this distribution or at
+ *  http://www.rtems.com/license/LICENSE.
+ *
+ *  $Id$
+ */
+
+#if HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <rtems/system.h>
+#include <rtems/score/apiext.h>
+#include <rtems/score/context.h>
+#include <rtems/score/interr.h>
+#include <rtems/score/isr.h>
+#include <rtems/score/object.h>
+#include <rtems/score/priority.h>
+#include <rtems/score/scheduler.h>
+#include <rtems/score/schedulerpriority.h>
+#include <rtems/score/states.h>
+#include <rtems/score/sysstate.h>
+#include <rtems/score/thread.h>
+#include <rtems/score/threadq.h>
+#include <rtems/score/userext.h>
+#include <rtems/score/wkspace.h>
+
+/*
+ *  _Scheduler_priority_Unblock
+ *
+ *  This kernel routine readies the requested thread according to the queuing 
+ *  discipline. A new heir thread may be selected.
+ *
+ *  Input parameters:
+ *    the_scheduler - pointer to scheduler control
+ *    the_thread    - pointer to thread control block
+ *
+ *  Output parameters:  NONE
+ *
+ *  NOTE:  This routine uses the "blocking" heir selection mechanism.
+ *         This ensures the correct heir after a thread restart.
+ *
+ *  INTERRUPT LATENCY:
+ */
+
+void _Scheduler_priority_Unblock (
+  Scheduler_Control       *the_scheduler,
+  Thread_Control          *the_thread
+)
+{
+  _Scheduler_priority_Unblock_body(the_scheduler, the_thread);
+}
diff --git a/cpukit/score/src/schedulerpriorityyield.c b/cpukit/score/src/schedulerpriorityyield.c
new file mode 100644
index 0000000000..1a13a4e318
--- /dev/null
+++ b/cpukit/score/src/schedulerpriorityyield.c
@@ -0,0 +1,77 @@
+/*
+ *  Scheduler Handler
+ *
+ *  Copyright (C) 2010 Gedare Bloom.
+ *
+ *  The license and distribution terms for this file may be
+ *  found in found in the file LICENSE in this distribution or at
+ *  http://www.rtems.com/license/LICENSE.
+ *
+ *  $Id$
+ */
+
+#if HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <rtems/system.h>
+#include <rtems/score/apiext.h>
+#include <rtems/score/context.h>
+#include <rtems/score/interr.h>
+#include <rtems/score/isr.h>
+#include <rtems/score/object.h>
+#include <rtems/score/priority.h>
+#include <rtems/score/scheduler.h>
+#include <rtems/score/states.h>
+#include <rtems/score/sysstate.h>
+#include <rtems/score/thread.h>
+#include <rtems/score/threadq.h>
+#include <rtems/score/userext.h>
+#include <rtems/score/wkspace.h>
+
+/*
+ *  _Scheduler_priority_Yield
+ *
+ *  This kernel routine will remove the running THREAD from the ready queue
+ *  and place it immediately at the rear of this chain.  Reset timeslice
+ *  and yield the processor functions both use this routine, therefore if
+ *  reset is true and this is the only thread on the queue then the
+ *  timeslice counter is reset.  The heir THREAD will be updated if the
+ *  running is also the currently the heir.
+ *
+ *  Input parameters:
+ *    the_scheduler - pointer to scheduler control
+ *
+ *  Output parameters:  NONE
+ *
+ *  INTERRUPT LATENCY:
+ *    ready chain
+ *    select heir
+ */
+
+void _Scheduler_priority_Yield( 
+    Scheduler_Control   *the_scheduler
+)
+{
+  ISR_Level       level;
+  Thread_Control *executing;
+  Chain_Control  *ready;
+
+  executing = _Thread_Executing;
+  ready = executing->scheduler.priority->ready_chain;
+  _ISR_Disable( level );
+    if ( !_Chain_Has_only_one_node( ready ) ) {
+      _Chain_Extract_unprotected( &executing->Object.Node );
+      _Chain_Append_unprotected( ready, &executing->Object.Node );
+
+      _ISR_Flash( level );
+
+      if ( _Thread_Is_heir( executing ) )
+        _Thread_Heir = (Thread_Control *) ready->first;
+      _Thread_Dispatch_necessary = true;
+    }
+    else if ( !_Thread_Is_heir( executing ) )
+      _Thread_Dispatch_necessary = true;
+
+  _ISR_Enable( level );
+}
diff --git a/cpukit/score/src/thread.c b/cpukit/score/src/thread.c
index f0891373f6..bf8e8939e7 100644
--- a/cpukit/score/src/thread.c
+++ b/cpukit/score/src/thread.c
@@ -24,6 +24,7 @@
 #include <rtems/score/isr.h>
 #include <rtems/score/object.h>
 #include <rtems/score/priority.h>
+#include <rtems/score/scheduler.h>
 #include <rtems/score/states.h>
 #include <rtems/score/sysstate.h>
 #include <rtems/score/thread.h>
@@ -45,7 +46,6 @@
 
 void _Thread_Handler_initialization(void)
 {
-  uint32_t     index;
   uint32_t     ticks_per_timeslice;
   uint32_t     maximum_extensions;
   #if defined(RTEMS_MULTIPROCESSING)
@@ -80,13 +80,6 @@ void _Thread_Handler_initialization(void)
 
   _Thread_Ticks_per_timeslice  = ticks_per_timeslice;
 
-  _Thread_Ready_chain = (Chain_Control *) _Workspace_Allocate_or_fatal_error(
-    (PRIORITY_MAXIMUM + 1) * sizeof(Chain_Control)
-  );
-
-  for ( index=0; index <= PRIORITY_MAXIMUM ; index++ )
-    _Chain_Initialize_empty( &_Thread_Ready_chain[ index ] );
-
 #if defined(RTEMS_MULTIPROCESSING)
   _Thread_MP_Handler_initialization( maximum_proxies );
 #endif
diff --git a/cpukit/score/src/threadchangepriority.c b/cpukit/score/src/threadchangepriority.c
index 58f5eb5fd3..7b46f799c7 100644
--- a/cpukit/score/src/threadchangepriority.c
+++ b/cpukit/score/src/threadchangepriority.c
@@ -23,6 +23,8 @@
 #include <rtems/score/isr.h>
 #include <rtems/score/object.h>
 #include <rtems/score/priority.h>
+#include <rtems/score/scheduler.h>
+#include <rtems/score/schedulerpriority.h>
 #include <rtems/score/states.h>
 #include <rtems/score/sysstate.h>
 #include <rtems/score/thread.h>
@@ -117,14 +119,16 @@ void _Thread_Change_priority(
      *  We now know the thread will be in the READY state when we remove
      *  the TRANSIENT state.  So we have to place it on the appropriate
      *  Ready Queue with interrupts off.
+     *
+     *  FIXME: hard-coded for priority scheduling. Might be ok since this 
+     *  function is specific to priority scheduling?
      */
     the_thread->current_state = _States_Clear( STATES_TRANSIENT, state );
 
-    _Priority_bit_map_Add( &the_thread->Priority_map );
     if ( prepend_it )
-      _Chain_Prepend_unprotected( the_thread->ready, &the_thread->Object.Node );
+      _Scheduler_priority_Ready_queue_enqueue_first( the_thread );
     else
-      _Chain_Append_unprotected( the_thread->ready, &the_thread->Object.Node );
+      _Scheduler_priority_Ready_queue_enqueue( the_thread );
   }
 
   _ISR_Flash( level );
@@ -133,7 +137,7 @@ void _Thread_Change_priority(
    *  We altered the set of thread priorities.  So let's figure out
    *  who is the heir and if we need to switch to them.
    */
-  _Thread_Calculate_heir();
+  _Scheduler_Schedule(&_Scheduler);
 
   if ( !_Thread_Is_executing_also_the_heir() &&
        _Thread_Executing->is_preemptible )
diff --git a/cpukit/score/src/threadclearstate.c b/cpukit/score/src/threadclearstate.c
index c5ab03497a..c3a9083197 100644
--- a/cpukit/score/src/threadclearstate.c
+++ b/cpukit/score/src/threadclearstate.c
@@ -23,6 +23,7 @@
 #include <rtems/score/isr.h>
 #include <rtems/score/object.h>
 #include <rtems/score/priority.h>
+#include <rtems/score/scheduler.h>
 #include <rtems/score/states.h>
 #include <rtems/score/sysstate.h>
 #include <rtems/score/thread.h>
@@ -66,31 +67,7 @@ void _Thread_Clear_state(
       the_thread->current_state = _States_Clear( state, current_state );
 
       if ( _States_Is_ready( current_state ) ) {
-
-        _Priority_bit_map_Add( &the_thread->Priority_map );
-
-        _Chain_Append_unprotected(the_thread->ready, &the_thread->Object.Node);
-
-        _ISR_Flash( level );
-
-        /*
-         *  If the thread that was unblocked is more important than the heir,
-         *  then we have a new heir.  This may or may not result in a
-         *  context switch.
-         *
-         *  Normal case:
-         *    If the current thread is preemptible, then we need to do
-         *    a context switch.
-         *  Pseudo-ISR case:
-         *    Even if the thread isn't preemptible, if the new heir is
-         *    a pseudo-ISR system task, we need to do a context switch.
-         */
-        if ( the_thread->current_priority < _Thread_Heir->current_priority ) {
-          _Thread_Heir = the_thread;
-          if ( _Thread_Executing->is_preemptible ||
-               the_thread->current_priority == 0 )
-            _Thread_Dispatch_necessary = true;
-        }
+        _Scheduler_Unblock( &_Scheduler, the_thread);
       }
   }
   _ISR_Enable( level );
diff --git a/cpukit/score/src/threadclose.c b/cpukit/score/src/threadclose.c
index 51db06f56c..5098f0fbc4 100644
--- a/cpukit/score/src/threadclose.c
+++ b/cpukit/score/src/threadclose.c
@@ -23,6 +23,7 @@
 #include <rtems/score/isr.h>
 #include <rtems/score/object.h>
 #include <rtems/score/priority.h>
+#include <rtems/score/scheduler.h>
 #include <rtems/score/states.h>
 #include <rtems/score/sysstate.h>
 #include <rtems/score/thread.h>
@@ -86,6 +87,11 @@ void _Thread_Close(
   }
 
   /*
+   * Free the per-thread scheduling information.
+   */
+  _Scheduler_Thread_scheduler_free( &_Scheduler, the_thread );
+
+  /*
    *  The thread might have been FP.  So deal with that.
    */
 #if ( CPU_HARDWARE_FP == TRUE ) || ( CPU_SOFTWARE_FP == TRUE )
diff --git a/cpukit/score/src/threadinitialize.c b/cpukit/score/src/threadinitialize.c
index 4afdbcb821..eda6f6bb5a 100644
--- a/cpukit/score/src/threadinitialize.c
+++ b/cpukit/score/src/threadinitialize.c
@@ -23,6 +23,7 @@
 #include <rtems/score/isr.h>
 #include <rtems/score/object.h>
 #include <rtems/score/priority.h>
+#include <rtems/score/scheduler.h>
 #include <rtems/score/states.h>
 #include <rtems/score/sysstate.h>
 #include <rtems/score/thread.h>
@@ -60,6 +61,7 @@ bool _Thread_Initialize(
   #if ( CPU_HARDWARE_FP == TRUE ) || ( CPU_SOFTWARE_FP == TRUE )
     void              *fp_area;
   #endif
+  void                *sched = NULL;
   void                *extensions_area;
   bool                 extension_status;
   int                  i;
@@ -192,6 +194,9 @@ bool _Thread_Initialize(
   the_thread->resource_count          = 0;
   the_thread->real_priority           = priority;
   the_thread->Start.initial_priority  = priority;
+  sched =_Scheduler_Thread_scheduler_allocate( &_Scheduler, the_thread );
+  if ( !sched )
+    goto failed;
   _Thread_Set_priority( the_thread, priority );
 
   /*
@@ -235,6 +240,9 @@ failed:
       (void) _Workspace_Free( fp_area );
   #endif
 
+  if ( sched )
+    (void) _Workspace_Free( sched );
+
    _Thread_Stack_Free( the_thread );
   return false;
 
diff --git a/cpukit/score/src/threadready.c b/cpukit/score/src/threadready.c
index 3daa6506bd..f0e006503c 100644
--- a/cpukit/score/src/threadready.c
+++ b/cpukit/score/src/threadready.c
@@ -23,6 +23,7 @@
 #include <rtems/score/isr.h>
 #include <rtems/score/object.h>
 #include <rtems/score/priority.h>
+#include <rtems/score/scheduler.h>
 #include <rtems/score/states.h>
 #include <rtems/score/sysstate.h>
 #include <rtems/score/thread.h>
@@ -55,24 +56,12 @@ void _Thread_Ready(
 )
 {
   ISR_Level              level;
-  Thread_Control *heir;
 
   _ISR_Disable( level );
 
   the_thread->current_state = STATES_READY;
 
-  _Priority_bit_map_Add( &the_thread->Priority_map );
-
-  _Chain_Append_unprotected( the_thread->ready, &the_thread->Object.Node );
-
-  _ISR_Flash( level );
-
-  _Thread_Calculate_heir();
-
-  heir = _Thread_Heir;
-
-  if ( !_Thread_Is_executing( heir ) && _Thread_Executing->is_preemptible )
-    _Thread_Dispatch_necessary = true;
+  _Scheduler_Unblock( &_Scheduler, the_thread );
 
   _ISR_Enable( level );
 }
diff --git a/cpukit/score/src/threadresume.c b/cpukit/score/src/threadresume.c
index c82466d3b3..1997c3c293 100644
--- a/cpukit/score/src/threadresume.c
+++ b/cpukit/score/src/threadresume.c
@@ -23,6 +23,7 @@
 #include <rtems/score/isr.h>
 #include <rtems/score/object.h>
 #include <rtems/score/priority.h>
+#include <rtems/score/scheduler.h>
 #include <rtems/score/states.h>
 #include <rtems/score/sysstate.h>
 #include <rtems/score/thread.h>
@@ -68,19 +69,7 @@ void _Thread_Resume(
     the_thread->current_state = _States_Clear(STATES_SUSPENDED, current_state);
 
     if ( _States_Is_ready( current_state ) ) {
-
-      _Priority_bit_map_Add( &the_thread->Priority_map );
-
-      _Chain_Append_unprotected(the_thread->ready, &the_thread->Object.Node);
-
-      _ISR_Flash( level );
-
-      if ( the_thread->current_priority < _Thread_Heir->current_priority ) {
-        _Thread_Heir = the_thread;
-        if ( _Thread_Executing->is_preemptible ||
-             the_thread->current_priority == 0 )
-          _Thread_Dispatch_necessary = true;
-      }
+      _Scheduler_Unblock( &_Scheduler, the_thread );
     }
   }
 
diff --git a/cpukit/score/src/threadsetpriority.c b/cpukit/score/src/threadsetpriority.c
index cfe069d4ae..b55de24b43 100644
--- a/cpukit/score/src/threadsetpriority.c
+++ b/cpukit/score/src/threadsetpriority.c
@@ -23,6 +23,7 @@
 #include <rtems/score/isr.h>
 #include <rtems/score/object.h>
 #include <rtems/score/priority.h>
+#include <rtems/score/scheduler.h>
 #include <rtems/score/states.h>
 #include <rtems/score/sysstate.h>
 #include <rtems/score/thread.h>
@@ -50,10 +51,6 @@ void _Thread_Set_priority(
 )
 {
   the_thread->current_priority = new_priority;
-  the_thread->ready            = &_Thread_Ready_chain[ new_priority ];
 
-  _Priority_bit_map_Initialize_information( 
-      &the_thread->Priority_map, 
-      new_priority 
-  );
+  _Scheduler_Thread_scheduler_update(&_Scheduler, the_thread);
 }
diff --git a/cpukit/score/src/threadsetstate.c b/cpukit/score/src/threadsetstate.c
index 2edd3bb70d..73a71b70e2 100644
--- a/cpukit/score/src/threadsetstate.c
+++ b/cpukit/score/src/threadsetstate.c
@@ -23,6 +23,7 @@
 #include <rtems/score/isr.h>
 #include <rtems/score/object.h>
 #include <rtems/score/priority.h>
+#include <rtems/score/scheduler.h>
 #include <rtems/score/states.h>
 #include <rtems/score/sysstate.h>
 #include <rtems/score/thread.h>
@@ -54,9 +55,7 @@ void _Thread_Set_state(
 )
 {
   ISR_Level      level;
-  Chain_Control *ready;
-
-  ready = the_thread->ready;
+  
   _ISR_Disable( level );
   if ( !_States_Is_ready( the_thread->current_state ) ) {
     the_thread->current_state =
@@ -67,21 +66,7 @@ void _Thread_Set_state(
 
   the_thread->current_state = state;
 
-  if ( _Chain_Has_only_one_node( ready ) ) {
-
-    _Chain_Initialize_empty( ready );
-    _Priority_bit_map_Remove( &the_thread->Priority_map );
-
-  } else
-    _Chain_Extract_unprotected( &the_thread->Object.Node );
-
-  _ISR_Flash( level );
-
-  if ( _Thread_Is_heir( the_thread ) )
-     _Thread_Calculate_heir();
-
-  if ( _Thread_Is_executing( the_thread ) )
-    _Thread_Dispatch_necessary = true;
+  _Scheduler_Block( &_Scheduler, the_thread);
 
   _ISR_Enable( level );
 }
diff --git a/cpukit/score/src/threadsettransient.c b/cpukit/score/src/threadsettransient.c
index 36f60a6077..ce697f2d02 100644
--- a/cpukit/score/src/threadsettransient.c
+++ b/cpukit/score/src/threadsettransient.c
@@ -23,6 +23,8 @@
 #include <rtems/score/isr.h>
 #include <rtems/score/object.h>
 #include <rtems/score/priority.h>
+#include <rtems/score/scheduler.h>
+#include <rtems/score/schedulerpriority.h>
 #include <rtems/score/states.h>
 #include <rtems/score/sysstate.h>
 #include <rtems/score/thread.h>
@@ -54,22 +56,15 @@ void _Thread_Set_transient(
 {
   ISR_Level             level;
   uint32_t              old_state;
-  Chain_Control *ready;
-
-  ready = the_thread->ready;
+  
   _ISR_Disable( level );
 
   old_state = the_thread->current_state;
   the_thread->current_state = _States_Set( STATES_TRANSIENT, old_state );
 
+  /* FIXME: need to check which scheduler to use? */
   if ( _States_Is_ready( old_state ) ) {
-    if ( _Chain_Has_only_one_node( ready ) ) {
-
-      _Chain_Initialize_empty( ready );
-      _Priority_bit_map_Remove( &the_thread->Priority_map );
-
-    } else
-      _Chain_Extract_unprotected( &the_thread->Object.Node );
+    _Scheduler_priority_Ready_queue_extract( the_thread);
   }
 
   _ISR_Enable( level );
diff --git a/cpukit/score/src/threadsuspend.c b/cpukit/score/src/threadsuspend.c
index 8cb2796691..8b4a631e5f 100644
--- a/cpukit/score/src/threadsuspend.c
+++ b/cpukit/score/src/threadsuspend.c
@@ -23,6 +23,7 @@
 #include <rtems/score/isr.h>
 #include <rtems/score/object.h>
 #include <rtems/score/priority.h>
+#include <rtems/score/scheduler.h>
 #include <rtems/score/states.h>
 #include <rtems/score/sysstate.h>
 #include <rtems/score/thread.h>
@@ -52,9 +53,7 @@ void _Thread_Suspend(
 )
 {
   ISR_Level      level;
-  Chain_Control *ready;
-
-  ready = the_thread->ready;
+  
   _ISR_Disable( level );
   if ( !_States_Is_ready( the_thread->current_state ) ) {
     the_thread->current_state =
@@ -65,21 +64,7 @@ void _Thread_Suspend(
 
   the_thread->current_state = STATES_SUSPENDED;
 
-  if ( _Chain_Has_only_one_node( ready ) ) {
-
-    _Chain_Initialize_empty( ready );
-    _Priority_bit_map_Remove( &the_thread->Priority_map );
-
-  } else
-    _Chain_Extract_unprotected( &the_thread->Object.Node );
-
-  _ISR_Flash( level );
-
-  if ( _Thread_Is_heir( the_thread ) )
-     _Thread_Calculate_heir();
-
-  if ( _Thread_Is_executing( the_thread ) )
-    _Thread_Dispatch_necessary = true;
+  _Scheduler_Block(&_Scheduler, the_thread);
 
   _ISR_Enable( level );
 }
diff --git a/cpukit/score/src/threadtickletimeslice.c b/cpukit/score/src/threadtickletimeslice.c
index b05305650a..951339cb42 100644
--- a/cpukit/score/src/threadtickletimeslice.c
+++ b/cpukit/score/src/threadtickletimeslice.c
@@ -23,6 +23,7 @@
 #include <rtems/score/isr.h>
 #include <rtems/score/object.h>
 #include <rtems/score/priority.h>
+#include <rtems/score/scheduler.h>
 #include <rtems/score/states.h>
 #include <rtems/score/sysstate.h>
 #include <rtems/score/thread.h>
@@ -89,7 +90,7 @@ void _Thread_Tickle_timeslice( void )
          *  currently executing thread is placed at the rear of the
          *  FIFO for this priority and a new heir is selected.
          */
-        _Thread_Yield_processor();
+        _Scheduler_Yield( );
         executing->cpu_time_budget = _Thread_Ticks_per_timeslice;
       }
       break;