smp: _Scheduler_simple_smp_Allocate_processor()

Rename _Scheduler_simple_smp_Allocate_processor() to
_Scheduler_SMP_Allocate_processor().

1 files changed, 42 insertions, 0 deletions

diff --git a/cpukit/score/include/rtems/score/schedulersmpimpl.h b/cpukit/score/include/rtems/score/schedulersmpimpl.h
index 7e123e2c39..d23b0c0f00 100644
--- a/cpukit/score/include/rtems/score/schedulersmpimpl.h
+++ b/cpukit/score/include/rtems/score/schedulersmpimpl.h
@@ -41,6 +41,48 @@ static inline Scheduler_SMP_Control *_Scheduler_SMP_Instance( void )
   return _Scheduler.information;
 }
 
+static inline void _Scheduler_SMP_Allocate_processor(
+  Thread_Control *scheduled,
+  Thread_Control *victim
+)
+{
+  Per_CPU_Control *cpu_of_scheduled = scheduled->cpu;
+  Per_CPU_Control *cpu_of_victim = victim->cpu;
+  Thread_Control *heir;
+
+  scheduled->is_scheduled = true;
+  victim->is_scheduled = false;
+
+  _Per_CPU_Acquire( cpu_of_scheduled );
+
+  if ( scheduled->is_executing ) {
+    heir = cpu_of_scheduled->heir;
+    cpu_of_scheduled->heir = scheduled;
+  } else {
+    heir = scheduled;
+  }
+
+  _Per_CPU_Release( cpu_of_scheduled );
+
+  if ( heir != victim ) {
+    const Per_CPU_Control *cpu_of_executing = _Per_CPU_Get();
+
+    heir->cpu = cpu_of_victim;
+
+    /*
+     * FIXME: Here we need atomic store operations with a relaxed memory order.
+     * The _CPU_SMP_Send_interrupt() will ensure that the change can be
+     * observed consistently.
+     */
+    cpu_of_victim->heir = heir;
+    cpu_of_victim->dispatch_necessary = true;
+
+    if ( cpu_of_victim != cpu_of_executing ) {
+      _Per_CPU_Send_interrupt( cpu_of_victim );
+    }
+  }
+}
+
 /** @} */
 
 #ifdef __cplusplus