score: Rework thread priority management

Add priority nodes which contribute to the overall thread priority.

The actual priority of a thread is now an aggregation of priority nodes.
The thread priority aggregation for the home scheduler instance of a
thread consists of at least one priority node, which is normally the
real priority of the thread.  The locking protocols (e.g. priority
ceiling and priority inheritance), rate-monotonic period objects and the
POSIX sporadic server add, change and remove priority nodes.

A thread changes its priority now immediately, e.g. priority changes are
not deferred until the thread releases its last resource.

Replace the _Thread_Change_priority() function with

 * _Thread_Priority_perform_actions(),
 * _Thread_Priority_add(),
 * _Thread_Priority_remove(),
 * _Thread_Priority_change(), and
 * _Thread_Priority_update().

Update #2412.
Update #2556.

1 files changed, 2 insertions, 2 deletions

diff --git a/cpukit/score/include/rtems/score/coremutex.h b/cpukit/score/include/rtems/score/coremutex.h
index a3dcabf523..d2bf1c21f6 100644
--- a/cpukit/score/include/rtems/score/coremutex.h
+++ b/cpukit/score/include/rtems/score/coremutex.h
@@ -82,9 +82,9 @@ typedef struct {
   CORE_recursive_mutex_Control Recursive;
 
   /**
-   * @brief The priority ceiling value for the mutex owner.
+   * @brief The priority ceiling node for the mutex owner.
    */
-  Priority_Control priority_ceiling;
+  Priority_Node Priority_ceiling;
 
 #if defined(RTEMS_SMP)
   /**