score: Add _Thread_Scheduler_process_requests()

Update #2556.

cpukit/score/Makefile.am

@@ -311,6 +311,7 @@ libscore_a_SOURCES += src/threadentryadaptorpointer.c
 libscore_a_SOURCES += src/threadgetcputimeused.c
 libscore_a_SOURCES += src/threadglobalconstruction.c
 libscore_a_SOURCES += src/threaditerate.c
+libscore_a_SOURCES += src/threadscheduler.c
 libscore_a_SOURCES += src/threadtimeout.c
 libscore_a_SOURCES += src/threadwaitgetid.c
 libscore_a_SOURCES += src/threadyield.c

cpukit/score/include/rtems/score/schedulerimpl.h

@@ -358,6 +358,10 @@ RTEMS_INLINE_ROUTINE void _Scheduler_Unblock( Thread_Control *the_thread )
   Thread_Control          *needs_help;
 #endif
 
+#if defined(RTEMS_SMP)
+  _Thread_Scheduler_process_requests( the_thread );
+#endif
+
   scheduler = _Scheduler_Get( the_thread );
   _Scheduler_Acquire_critical( scheduler, &lock_context );
 
@@ -399,6 +403,10 @@ RTEMS_INLINE_ROUTINE void _Scheduler_Update_priority( Thread_Control *the_thread
   Thread_Control          *needs_help;
 #endif
 
+#if defined(RTEMS_SMP)
+  _Thread_Scheduler_process_requests( the_thread );
+#endif
+
   own_scheduler = _Scheduler_Get_own( the_thread );
   _Scheduler_Acquire_critical( own_scheduler, &lock_context );
 
@@ -1449,6 +1457,7 @@ RTEMS_INLINE_ROUTINE Status_Control _Scheduler_Set(
   }
 
 #if defined(RTEMS_SMP)
+  _Thread_Scheduler_process_requests( the_thread );
   new_scheduler_node = _Thread_Scheduler_get_node_by_index(
     the_thread,
     _Scheduler_Get_index( new_scheduler )

cpukit/score/include/rtems/score/schedulernode.h

@@ -185,13 +185,20 @@ struct Scheduler_Node {
 
     /**
      * @brief Node to add this scheduler node to
-     * Thread_Control::Scheduler::Scheduler_nodes.
+     * Thread_Control::Scheduler::Scheduler_nodes or a temporary remove list.
      */
     union {
       /**
        * @brief The node for Thread_Control::Scheduler::Scheduler_nodes.
        */
       Chain_Node Chain;
+
+      /**
+       * @brief The next pointer for a temporary remove list.
+       *
+       * @see _Thread_Scheduler_process_requests().
+       */
+      Scheduler_Node *next;
     } Scheduler_node;
 
     /**

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

@@ -1051,6 +1051,8 @@ RTEMS_INLINE_ROUTINE void _Thread_Scheduler_release_critical(
   _ISR_lock_Release( &the_thread->Scheduler.Lock, lock_context );
 }
 
+void _Thread_Scheduler_process_requests( Thread_Control *the_thread );
+
 RTEMS_INLINE_ROUTINE void _Thread_Scheduler_add_request(
   Thread_Control         *the_thread,
   Scheduler_Node         *scheduler_node,

cpukit/score/src/threadscheduler.c

@@ -0,0 +1,84 @@
+/*
+ * Copyright (c) 2016 embedded brains GmbH.  All rights reserved.
+ *
+ *  embedded brains GmbH
+ *  Dornierstr. 4
+ *  82178 Puchheim
+ *  Germany
+ *  <rtems@embedded-brains.de>
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.org/license/LICENSE.
+ */
+
+#if HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <rtems/score/threadimpl.h>
+#include <rtems/score/schedulerimpl.h>
+
+#if defined(RTEMS_SMP)
+void _Thread_Scheduler_process_requests( Thread_Control *the_thread )
+{
+  ISR_lock_Context  lock_context;
+  Scheduler_Node   *scheduler_node;
+
+  _Thread_Scheduler_acquire_critical( the_thread, &lock_context );
+
+  scheduler_node = the_thread->Scheduler.requests;
+
+  if ( scheduler_node != NULL ) {
+    Scheduler_Node *next;
+    Scheduler_Node *remove;
+
+    the_thread->Scheduler.requests = NULL;
+    remove = NULL;
+
+    do {
+      Scheduler_Node_request request;
+
+      request = scheduler_node->Thread.request;
+      scheduler_node->Thread.request = SCHEDULER_NODE_REQUEST_NOT_PENDING;
+
+      next = scheduler_node->Thread.next_request;
+#if defined(RTEMS_DEBUG)
+      scheduler_node->Thread.next_request = NULL;
+#endif
+
+      if ( request == SCHEDULER_NODE_REQUEST_ADD ) {
+        _Chain_Append_unprotected(
+          &the_thread->Scheduler.Scheduler_nodes,
+          &scheduler_node->Thread.Scheduler_node.Chain
+        );
+      } else if ( request == SCHEDULER_NODE_REQUEST_REMOVE ) {
+        _Chain_Extract_unprotected(
+          &scheduler_node->Thread.Scheduler_node.Chain
+        );
+        scheduler_node->Thread.Scheduler_node.next = remove;
+        remove = scheduler_node;
+      } else {
+        _Assert( request == SCHEDULER_NODE_REQUEST_NOTHING );
+      }
+
+      scheduler_node = next;
+    } while ( scheduler_node != NULL );
+
+    _Thread_Scheduler_release_critical( the_thread, &lock_context );
+
+    scheduler_node = remove;
+
+    while ( scheduler_node != NULL ) {
+      next = scheduler_node->Thread.Scheduler_node.next;
+#if defined(RTEMS_DEBUG)
+      scheduler_node->Thread.Scheduler_node.next = NULL;
+#endif
+
+      scheduler_node = next;
+    }
+  } else {
+    _Thread_Scheduler_release_critical( the_thread, &lock_context );
+  }
+}
+#endif