score: Add and use thread get/set CPU functions

cpukit/libmisc/cpuuse/cpuusagereport.c

@@ -26,6 +26,7 @@
 
 #include <rtems/cpuuse.h>
 #include <rtems/score/objectimpl.h>
+#include <rtems/score/threadimpl.h>
 #include <rtems/score/todimpl.h>
 #include <rtems/score/watchdogimpl.h>
 
@@ -43,7 +44,8 @@
     #else
       /* FIXME: Locking */
       if ( the_thread->is_executing ) {
-        *time_of_context_switch = the_thread->cpu->time_of_last_context_switch;
+        *time_of_context_switch =
+          _Thread_Get_CPU( the_thread )->time_of_last_context_switch;
         return true;
       }
     #endif

cpukit/score/include/rtems/score/schedulersmpimpl.h

@@ -67,8 +67,8 @@ static inline void _Scheduler_SMP_Allocate_processor(
   Thread_Control *victim
 )
 {
-  Per_CPU_Control *cpu_of_scheduled = scheduled->cpu;
+  Per_CPU_Control *cpu_of_scheduled = _Thread_Get_CPU( scheduled );
-  Per_CPU_Control *cpu_of_victim = victim->cpu;
+  Per_CPU_Control *cpu_of_victim = _Thread_Get_CPU( victim );
   Thread_Control *heir;
 
   scheduled->is_scheduled = true;
@@ -88,7 +88,7 @@ static inline void _Scheduler_SMP_Allocate_processor(
   if ( heir != victim ) {
     const Per_CPU_Control *cpu_of_executing = _Per_CPU_Get();
 
-    heir->cpu = cpu_of_victim;
+    _Thread_Set_CPU( heir, cpu_of_victim );
 
     /*
      * FIXME: Here we need atomic store operations with a relaxed memory order.

cpukit/score/include/rtems/score/threadimpl.h

@@ -432,6 +432,32 @@ void _Thread_blocking_operation_Cancel(
   ISR_Level                         level
 );
 
+RTEMS_INLINE_ROUTINE Per_CPU_Control *_Thread_Get_CPU(
+  const Thread_Control *thread
+)
+{
+#if defined(RTEMS_SMP)
+  return thread->cpu;
+#else
+  (void) thread;
+
+  return _Per_CPU_Get();
+#endif
+}
+
+RTEMS_INLINE_ROUTINE void _Thread_Set_CPU(
+  Thread_Control *thread,
+  Per_CPU_Control *cpu
+)
+{
+#if defined(RTEMS_SMP)
+  thread->cpu = cpu;
+#else
+  (void) thread;
+  (void) cpu;
+#endif
+}
+
 /**
  * This function returns true if the_thread is the currently executing
  * thread, and false otherwise.
@@ -584,7 +610,7 @@ RTEMS_INLINE_ROUTINE void _Thread_Signal_notification( Thread_Control *thread )
 #if defined(RTEMS_SMP)
     if ( thread->is_executing ) {
       const Per_CPU_Control *cpu_of_executing = _Per_CPU_Get();
-      Per_CPU_Control *cpu_of_thread = thread->cpu;
+      Per_CPU_Control *cpu_of_thread = _Thread_Get_CPU( thread );
 
       if ( cpu_of_executing != cpu_of_thread ) {
         cpu_of_thread->dispatch_necessary = true;

cpukit/score/src/schedulersmpstartidle.c

@@ -35,6 +35,6 @@ void _Scheduler_SMP_Start_idle(
   Scheduler_SMP_Control *self = _Scheduler_SMP_Instance();
 
   thread->is_scheduled = true;
-  thread->cpu = cpu;
+  _Thread_Set_CPU( thread, cpu );
   _Chain_Append_unprotected( &self->scheduled, &thread->Object.Node );
 }

cpukit/score/src/threadinitialize.c

@@ -205,15 +205,15 @@ bool _Thread_Initialize(
   the_thread->is_scheduled            = false;
   the_thread->is_in_the_air           = false;
   the_thread->is_executing            = false;
-
-  /* Initialize the cpu field for the non-SMP schedulers */
-  the_thread->cpu                     = _Per_CPU_Get_by_index( 0 );
 #if __RTEMS_HAVE_SYS_CPUSET_H__
    the_thread->affinity               = *(_CPU_set_Default());
    the_thread->affinity.set           = &the_thread->affinity.preallocated;
 #endif
 #endif
 
+  /* Initialize the CPU for the non-SMP schedulers */
+  _Thread_Set_CPU( the_thread, _Per_CPU_Get_by_index( 0 ) );
+
   the_thread->current_state           = STATES_DORMANT;
   the_thread->Wait.queue              = NULL;
   the_thread->resource_count          = 0;