score: New thread queue implementation

Use thread wait flags for synchronization.  The enqueue operation is now
part of the initial critical section.  This is the key change and
enables fine grained locking on SMP for objects using a thread queue
like semaphores and message queues.

Update #2273.

1 files changed, 20 insertions, 4 deletions

diff --git a/cpukit/score/src/threadqflush.c b/cpukit/score/src/threadqflush.c
index 1abe8aca3e..d37b9e8ae7 100644
--- a/cpukit/score/src/threadqflush.c
+++ b/cpukit/score/src/threadqflush.c
@@ -31,14 +31,30 @@ void _Thread_queue_Flush(
   uint32_t                    status
 )
 {
-  Thread_Control *the_thread;
+  ISR_lock_Context  lock_context;
+  Thread_Control   *the_thread;
+
+  _Thread_queue_Acquire( the_thread_queue, &lock_context );
+
+  while ( (the_thread = _Thread_queue_First_locked( the_thread_queue ) ) ) {
+#if defined(RTEMS_MULTIPROCESSING)
+    if ( _Objects_Is_local_id( the_thread->Object.id ) )
+#endif
+      the_thread->Wait.return_code = status;
+
+    _Thread_queue_Extract_critical(
+      the_thread_queue,
+      the_thread,
+      &lock_context
+    );
 
-  while ( (the_thread = _Thread_queue_Dequeue( the_thread_queue )) ) {
 #if defined(RTEMS_MULTIPROCESSING)
     if ( !_Objects_Is_local_id( the_thread->Object.id ) )
       ( *remote_extract_callout )( the_thread );
-    else
 #endif
-      the_thread->Wait.return_code = status;
+
+    _Thread_queue_Acquire( the_thread_queue, &lock_context );
   }
+
+  _Thread_queue_Release( the_thread_queue, &lock_context );
 }