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counter ensures that the scheduler discards out-of-date priorities.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, 0 insertions, 16 deletions

diff --git a/cpukit/score/include/rtems/score/thread.h b/cpukit/score/include/rtems/score/thread.h
index cde31b48c1..4d498e5f3f 100644
--- a/cpukit/score/include/rtems/score/thread.h
+++ b/cpukit/score/include/rtems/score/thread.h
@@ -363,14 +363,6 @@ typedef struct {
   Priority_Control         real_priority;
 
   /**
-   * @brief Generation of the current priority value.
-   *
-   * It is used in _Thread_Change_priority() to serialize the update of
-   * priority related data structures.
-   */
-  uint32_t                 priority_generation;
-
-  /**
    * @brief Hints if a priority restore is necessary once the resource count
    * changes from one to zero.
    *
@@ -744,14 +736,6 @@ struct _Thread_Control {
   Priority_Control         real_priority;
 
   /**
-   * @brief Generation of the current priority value.
-   *
-   * It is used in _Thread_Change_priority() to serialize the update of
-   * priority related data structures.
-   */
-  uint32_t                 priority_generation;
-
-  /**
    * @brief Hints if a priority restore is necessary once the resource count
    * changes from one to zero.
    *