score: Introduce CPU budget operations

This patch set replaces the CPU budget algorithm enumeration with a set of CPU
budget operations which implement a particular CPU budget algorithm.  This
helps to hide the CPU budget algorithm implementation details from the general
thread handling.  The CPU budget callouts are turned into CPU budget
operations.  This slightly reduces the size of the thread control block.

All schedulers used the default scheduler tick implementation.  The tick
scheduler operation is removed and the CPU budget operations are directly used
in _Watchdog_Tick() if the executing thread uses a CPU budget algorithm.  This
is performance improvement for all threads which do not use a CPU budget
algorithm (default behaviour).

1 files changed, 2 insertions, 9 deletions

diff --git a/cpukit/include/rtems/score/schedulercbs.h b/cpukit/include/rtems/score/schedulercbs.h
index 4b7efc8340..8a9a49ccd9 100644
--- a/cpukit/include/rtems/score/schedulercbs.h
+++ b/cpukit/include/rtems/score/schedulercbs.h
@@ -67,7 +67,6 @@ extern "C" {
     _Scheduler_default_Node_destroy, /* node destroy entry point */ \
     _Scheduler_CBS_Release_job,      /* new period of task */ \
     _Scheduler_CBS_Cancel_job,       /* cancel period of task */ \
-    _Scheduler_default_Tick,         /* tick entry point */ \
     _Scheduler_default_Start_idle    /* start idle entry point */ \
     SCHEDULER_DEFAULT_SET_AFFINITY_OPERATION \
   }
@@ -394,15 +393,9 @@ int _Scheduler_CBS_Set_parameters (
 );
 
 /**
- * @brief Invoked when a limited time quantum is exceeded.
- *
- * This routine is invoked when a limited time quantum is exceeded.
- *
- * @param the_thread The thread that exceeded a limited time quantum.
+ * @brief These are the CBS CPU budget operations.
  */
-void _Scheduler_CBS_Budget_callout(
-  Thread_Control *the_thread
-);
+extern const Thread_CPU_budget_operations _Scheduler_CBS_Budget;
 
 /**
  * @brief Initializes a CBS specific scheduler node of @a the_thread.