score: Add thread priority to scheduler nodes

The thread priority is manifest in two independent areas.  One area is
the user visible thread priority along with a potential thread queue.
The other is the scheduler.  Currently, a thread priority update via
_Thread_Change_priority() first updates the user visble thread priority
and the thread queue, then the scheduler is notified if necessary.  The
priority is passed to the scheduler via a local variable.  A generation
counter ensures that the scheduler discards out-of-date priorities.

This use of a local variable ties the update in these two areas close
together.  For later enhancements and the OMIP locking protocol
implementation we need more flexibility.  Add a thread priority
information block to Scheduler_Node and synchronize priority value
updates via a sequence lock on SMP configurations.

Update #2556.

1 files changed, 21 insertions, 0 deletions

diff --git a/cpukit/score/src/schedulerpriority.c b/cpukit/score/src/schedulerpriority.c
index 61505a4fce..2719697ba3 100644
--- a/cpukit/score/src/schedulerpriority.c
+++ b/cpukit/score/src/schedulerpriority.c
@@ -32,3 +32,24 @@ void _Scheduler_priority_Initialize( const Scheduler_Control *scheduler )
     scheduler->maximum_priority
   );
 }
+
+void _Scheduler_priority_Node_initialize(
+  const Scheduler_Control *scheduler,
+  Thread_Control          *the_thread,
+  Priority_Control         priority
+)
+{
+  Scheduler_priority_Context *context;
+  Scheduler_priority_Node    *node;
+
+  context = _Scheduler_priority_Get_context( scheduler );
+  node = _Scheduler_priority_Thread_get_node( the_thread );
+
+  _Scheduler_Node_do_initialize( &node->Base, the_thread, priority );
+  _Scheduler_priority_Ready_queue_update(
+    &node->Ready_queue,
+    priority,
+    &context->Bit_map,
+    &context->Ready[ 0 ]
+  );
+}