Add SMP Priority Scheduler with Affinity

This scheduler attempts to account for needed thread migrations caused
as a side-effect of a thread state, affinity, or priority change operation.

This scheduler has its own allocate_processor handler named
_Scheduler_SMP_Allocate_processor_exact() because
_Scheduler_SMP_Allocate_processor() attempts to prevent an executing
thread from moving off its current CPU without considering affinity.
Without this, the scheduler makes all the right decisions and then
they are discarded at the end.

==Side Effects of Adding This Scheduler==

Added Thread_Control * parameter to Scheduler_SMP_Get_highest_ready type
so methods looking for the highest ready thread can filter by the processor
on which the thread blocking resides. This allows affinity to be considered.
Simple Priority SMP and Priority SMP ignore this parameter.

+ Added get_lowest_scheduled argument to _Scheduler_SMP_Enqueue_ordered().

+ Added allocate_processor argument to the following methods:
  - _Scheduler_SMP_Block()
  - _Scheduler_SMP_Enqueue_scheduled_ordered()
  - _Scheduler_SMP_Enqueue_scheduled_ordered()

+ schedulerprioritysmpimpl.h is a new file with prototypes for methods
  which were formerly static in schedulerprioritysmp.c but now need to
  be public to be shared with this scheduler.

NOTE:
  _Scheduler_SMP_Get_lowest_ready() appears to have a path which would
  allow it to return a NULL.  Previously, _Scheduler_SMP_Enqueue_ordered()
  would have asserted on it. If it cannot return a NULL,
  _Scheduler_SMP_Get_lowest_ready() should have an assertions.

1 files changed, 56 insertions, 12 deletions

diff --git a/cpukit/score/include/rtems/score/schedulerpriorityaffinitysmp.h b/cpukit/score/include/rtems/score/schedulerpriorityaffinitysmp.h
index 0ba8191e44..831d1d47a6 100644
--- a/cpukit/score/include/rtems/score/schedulerpriorityaffinitysmp.h
+++ b/cpukit/score/include/rtems/score/schedulerpriorityaffinitysmp.h
@@ -52,9 +52,9 @@ extern "C" {
     _Scheduler_priority_SMP_Initialize, \
     _Scheduler_default_Schedule, \
     _Scheduler_priority_SMP_Yield, \
-    _Scheduler_priority_SMP_Block, \
-    _Scheduler_priority_SMP_Unblock, \
-    _Scheduler_priority_SMP_Change_priority, \
+    _Scheduler_priority_affinity_SMP_Block, \
+    _Scheduler_priority_affinity_SMP_Unblock, \
+    _Scheduler_priority_affinity_SMP_Change_priority, \
     _Scheduler_priority_affinity_SMP_Node_initialize, \
     _Scheduler_default_Node_destroy, \
     _Scheduler_priority_SMP_Update_priority, \
@@ -67,21 +67,47 @@ extern "C" {
   }
 
 /**
- *  @brief Allocates @a the_thread->scheduler.
+ *  @brief Initializes per thread scheduler information
  *
- *  This routine allocates @a the_thread->scheduler.
+ *  This routine allocates @a thread->scheduler.
  *
  *  @param[in] scheduler points to the scheduler specific information.
- *  @param[in] the_thread is the thread the scheduler is allocating
+ *  @param[in] thread is the thread the scheduler is allocating
  *             management memory for.
  */
 void _Scheduler_priority_affinity_SMP_Node_initialize(
   const Scheduler_Control *scheduler,
-  Thread_Control          *the_thread
+  Thread_Control          *thread
 );
 
 /**
- * @brief Get affinity for the priority affinity smp scheduler.
+ * @brief SMP Priority Affinity Scheduler Block Operation
+ *
+ * This method is the block operation for this scheduler.
+ *
+ * @param[in] scheduler is the scheduler instance information
+ * @param[in] thread is the thread to block
+ */
+void _Scheduler_priority_affinity_SMP_Block(
+  const Scheduler_Control *scheduler,
+  Thread_Control          *thread
+);
+
+/**
+ * @brief SMP Priority Affinity Scheduler Unblock Operation
+ *
+ * This method is the unblock operation for this scheduler.
+ *
+ * @param[in] scheduler is the scheduler instance information
+ * @param[in] thread is the thread to unblock
+ */
+void _Scheduler_priority_affinity_SMP_Unblock(
+  const Scheduler_Control *scheduler,
+  Thread_Control          *thread
+);
+
+/**
+ * @brief Get affinity for the priority affinity SMP scheduler.
  *
  * @param[in] scheduler The scheduler of the thread.
  * @param[in] thread The associated thread.
@@ -98,26 +124,44 @@ bool _Scheduler_priority_affinity_SMP_Get_affinity(
   cpu_set_t               *cpuset
 );
 
+/**
+ * @brief Change priority for the priority affinity SMP scheduler.
+ *
+ * @param[in] scheduler The scheduler of the thread.
+ * @param[in] thread The associated thread.
+ * @param[in] new_priority The new priority for the thread.
+ * @param[in] prepend_it Append or prepend the thread to its priority FIFO.
+ */
+void _Scheduler_priority_affinity_SMP_Change_priority(
+  const Scheduler_Control *scheduler,
+  Thread_Control          *the_thread,
+  Priority_Control         new_priority,
+  bool                     prepend_it
+);
+
 /** 
- * @brief Set affinity for the priority affinity smp scheduler.
+ * @brief Set affinity for the priority affinity SMP scheduler.
  *
  * @param[in] scheduler The scheduler of the thread.
  * @param[in] thread The associated thread.
  * @param[in] cpusetsize The size of the cpuset.
  * @param[in] cpuset Affinity new affinity set.
  *
- * @retval 0 Successful
+ * @retval true if successful
+ * @retval false if unsuccessful
  */
 bool _Scheduler_priority_affinity_SMP_Set_affinity(
   const Scheduler_Control *scheduler,
   Thread_Control          *thread,
   size_t                   cpusetsize,
-  cpu_set_t               *cpuset
+  const cpu_set_t         *cpuset
 );
 
 /**
  * @brief Scheduler node specialization for Deterministic Priority Affinity SMP
  * schedulers.
+ *
+ * This is a per thread structure.
  */
 typedef struct {
   /**
@@ -137,4 +181,4 @@ typedef struct {
 }
 #endif /* __cplusplus */
 
-#endif /* _RTEMS_SCORE_SCHEDULERPRIORITYSMP_H */
+#endif /* _RTEMS_SCORE_SCHEDULERPRIORITYAFFINITYSMP_H */