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, 0 deletions

diff --git a/cpukit/rtems/src/ratemoncreate.c b/cpukit/rtems/src/ratemoncreate.c
index a86c6a1eeb..12327295ac 100644
--- a/cpukit/rtems/src/ratemoncreate.c
+++ b/cpukit/rtems/src/ratemoncreate.c
@@ -63,6 +63,8 @@ rtems_status_code rtems_rate_monotonic_create(
   }
 
   _ISR_lock_Initialize( &the_period->Lock, "Rate Monotonic Period" );
+  _Priority_Node_initialize( &the_period->Priority, 0 );
+  _Priority_Node_set_inactive( &the_period->Priority );
 
   the_period->owner = _Thread_Get_executing();
   the_period->state = RATE_MONOTONIC_INACTIVE;