1 files changed, 87 insertions, 0 deletions
diff --git a/cpukit/rtems/src/regionprocessqueue.c b/cpukit/rtems/src/regionprocessqueue.c
new file mode 100644
index 0000000000..011e646a6c
--- /dev/null
+++ b/cpukit/rtems/src/regionprocessqueue.c
@@ -0,0 +1,87 @@
+/*
+ *  Region Manager
+ *
+ *
+ *  COPYRIGHT (c) 1989-1999.
+ *  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/rtems/status.h>
+#include <rtems/rtems/support.h>
+#include <rtems/score/object.h>
+#include <rtems/rtems/options.h>
+#include <rtems/rtems/region.h>
+#include <rtems/score/states.h>
+#include <rtems/score/thread.h>
+#include <rtems/score/apimutex.h>
+
+/*PAGE
+ *
+ *  _Region_Process_queue
+ *
+ *  If enough memory is available to satisfy the rtems_region_get_segment of
+ *  the first blocked task, then that task and as many subsequent tasks as
+ *  possible will be unblocked with their requests satisfied.
+ *
+ *  Input parameters:
+ *    the_region - the region
+ *
+ *  Output parameters:
+ *    none
+ */
+
+void _Region_Process_queue(
+  Region_Control *the_region
+)
+{
+  Thread_Control *the_thread;
+  void           *the_segment;
+  /*
+   *  Switch from using the memory allocation mutex to using a
+   *  dispatching disabled critical section.  We have to do this
+   *  because this thread may unblock one or more threads that were
+   *  waiting on memory.
+   *
+   *  NOTE: Be sure to disable dispatching before unlocking the mutex
+   *        since we do not want to open a window where a context
+   *        switch could occur.
+   */
+  _Thread_Disable_dispatch();
+  _RTEMS_Unlock_allocator();
+
+  /*
+   *  NOTE: The following loop is O(n) where n is the number of
+   *        threads whose memory request is satisfied.
+   */
+  for ( ; ; ) {
+    the_thread = _Thread_queue_First( &the_region->Wait_queue );
+
+    if ( the_thread == NULL )
+      break;
+
+    the_segment = (void **) _Region_Allocate_segment(
+      the_region,
+      the_thread->Wait.count
+    );
+
+    if ( the_segment == NULL )
+      break;
+
+    *(void **)the_thread->Wait.return_argument = the_segment;
+    the_region->number_of_used_blocks += 1;
+    _Thread_queue_Extract( &the_region->Wait_queue, the_thread );
+    the_thread->Wait.return_code = RTEMS_SUCCESSFUL;
+  }
+  _Thread_Enable_dispatch();
+}