score: Add per scheduler instance maximum priority

The priority values are only valid within a scheduler instance.  Thus,
the maximum priority value must be defined per scheduler instance.  The
first scheduler instance defines PRIORITY_MAXIMUM.  This implies that
RTEMS_MAXIMUM_PRIORITY and POSIX_SCHEDULER_MAXIMUM_PRIORITY are only
valid for threads of the first scheduler instance.  Further
API/implementation changes are necessary to fix this.

Update #2556.

6 files changed, 22 insertions, 8 deletions

diff --git a/cpukit/score/include/rtems/score/priority.h b/cpukit/score/include/rtems/score/priority.h
index 0a772f62a2..38f3995e61 100644
--- a/cpukit/score/include/rtems/score/priority.h
+++ b/cpukit/score/include/rtems/score/priority.h
@@ -72,14 +72,6 @@ typedef uint32_t   Priority_Control;
   #define PRIORITY_DEFAULT_MAXIMUM      255
 #endif
 
-/** This defines the lowest (least important) thread priority. */
-#define PRIORITY_MAXIMUM      rtems_maximum_priority
-
-/**
- *  This variable contains the configured number of priorities
- */
-extern uint8_t rtems_maximum_priority;
-
 #ifdef __cplusplus
 }
 #endif
diff --git a/cpukit/score/include/rtems/score/scheduler.h b/cpukit/score/include/rtems/score/scheduler.h
index 5296644aeb..1e6236fa4d 100644
--- a/cpukit/score/include/rtems/score/scheduler.h
+++ b/cpukit/score/include/rtems/score/scheduler.h
@@ -201,6 +201,14 @@ struct Scheduler_Control {
   Scheduler_Operations Operations;
 
   /**
+   * @brief The maximum priority value of this scheduler.
+   *
+   * It defines the lowest (least important) thread priority for this
+   * scheduler.  For example the idle threads have this priority.
+   */
+  Priority_Control maximum_priority;
+
+  /**
    * @brief The scheduler name.
    */
   uint32_t name;
@@ -555,6 +563,12 @@ void _Scheduler_default_Start_idle(
   #define SCHEDULER_OPERATION_DEFAULT_GET_SET_AFFINITY
 #endif
 
+/**
+ * @brief This defines the lowest (least important) thread priority of the
+ * first scheduler instance.
+ */
+#define PRIORITY_MAXIMUM ( _Scheduler_Table[ 0 ].maximum_priority )
+
 /**@}*/
 
 #ifdef __cplusplus
diff --git a/cpukit/score/include/rtems/score/schedulercbs.h b/cpukit/score/include/rtems/score/schedulercbs.h
index 5558d6e919..e390532343 100644
--- a/cpukit/score/include/rtems/score/schedulercbs.h
+++ b/cpukit/score/include/rtems/score/schedulercbs.h
@@ -39,6 +39,8 @@ extern "C" {
  */
 /**@{*/
 
+#define SCHEDULER_CBS_MAXIMUM_PRIORITY SCHEDULER_EDF_MAXIMUM_PRIORITY
+
 /**
  *  Entry points for the Constant Bandwidth Server Scheduler.
  *
diff --git a/cpukit/score/include/rtems/score/scheduleredf.h b/cpukit/score/include/rtems/score/scheduleredf.h
index 9b0d1b4099..137ea3abde 100644
--- a/cpukit/score/include/rtems/score/scheduleredf.h
+++ b/cpukit/score/include/rtems/score/scheduleredf.h
@@ -35,6 +35,8 @@ extern "C" {
  */
 /**@{*/
 
+#define SCHEDULER_EDF_MAXIMUM_PRIORITY 255
+
 /**
  *  Entry points for the Earliest Deadline First Scheduler.
  */
diff --git a/cpukit/score/include/rtems/score/schedulersimple.h b/cpukit/score/include/rtems/score/schedulersimple.h
index 201c1b6628..a546ed629f 100644
--- a/cpukit/score/include/rtems/score/schedulersimple.h
+++ b/cpukit/score/include/rtems/score/schedulersimple.h
@@ -32,6 +32,8 @@ extern "C" {
  */
 /**@{*/
 
+#define SCHEDULER_SIMPLE_MAXIMUM_PRIORITY 255
+
 /**
  *  Entry points for Scheduler Simple
  */
diff --git a/cpukit/score/include/rtems/score/schedulersimplesmp.h b/cpukit/score/include/rtems/score/schedulersimplesmp.h
index 11310c6898..342a574174 100644
--- a/cpukit/score/include/rtems/score/schedulersimplesmp.h
+++ b/cpukit/score/include/rtems/score/schedulersimplesmp.h
@@ -54,6 +54,8 @@ typedef struct {
   Chain_Control         Ready;
 } Scheduler_simple_SMP_Context;
 
+#define SCHEDULER_SIMPLE_SMP_MAXIMUM_PRIORITY 255
+
 /**
  * @brief Entry points for the Simple SMP Scheduler.
  */