1 files changed, 52 insertions, 0 deletions
diff --git a/cpukit/score/src/schedulersimplereadyqueueenqueuefirst.c b/cpukit/score/src/schedulersimplereadyqueueenqueuefirst.c
new file mode 100644
index 0000000000..dee0bbd116
--- /dev/null
+++ b/cpukit/score/src/schedulersimplereadyqueueenqueuefirst.c
@@ -0,0 +1,52 @@
+/*
+ *  Schedule Simple Handler / Ready Queue Enqueue First
+ *
+ *  COPYRIGHT (c) 2011.
+ *  On-Line Applications Research Corporation (OAR).
+ *
+ *  The license and distribution terms for this file may be
+ *  found in the file LICENSE in this distribution or at
+ *  http://www.rtems.com/license/LICENSE.
+ *
+ *  $Id$
+ */
+
+#if HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <rtems/system.h>
+#include <rtems/score/chain.h>
+#include <rtems/score/thread.h>
+#include <rtems/score/schedulersimple.h>
+
+void _Scheduler_simple_Ready_queue_Enqueue_first(
+  Thread_Control    *the_thread
+)
+{
+  Chain_Control    *ready;
+  Chain_Node       *the_node;
+  Thread_Control   *current;
+
+  ready    = (Chain_Control *)_Scheduler.information;
+  current  = (Thread_Control *)ready;
+
+  /*
+   * Do NOT need to check for end of chain because there is always
+   * at least one task on the ready chain -- the IDLE task.  It can
+   * never block, should never attempt to obtain a semaphore or mutex,
+   * and thus will always be there.
+   */
+  for ( the_node = _Chain_First(ready) ; ; the_node = the_node->next ) {
+    current = (Thread_Control *) the_node;
+
+    /* break when AT HEAD OF (or PAST) our priority */
+    if ( the_thread->current_priority <= current->current_priority ) {
+      current = (Thread_Control *)current->Object.Node.previous;
+      break;
+    }
+  }
+
+  /* enqueue */
+  _Chain_Insert_unprotected( (Chain_Node *)current, &the_thread->Object.Node );
+}