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diff --git a/cpukit/score/include/rtems/score/schedulernode.h b/cpukit/score/include/rtems/score/schedulernode.h
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+++ b/cpukit/score/include/rtems/score/schedulernode.h
@@ -0,0 +1,188 @@
+/*
+ * Copyright (c) 2014, 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.
+ */
+
+#ifndef _RTEMS_SCORE_SCHEDULERNODE_H
+#define _RTEMS_SCORE_SCHEDULERNODE_H
+
+#include <rtems/score/basedefs.h>
+#include <rtems/score/chain.h>
+#include <rtems/score/priority.h>
+#include <rtems/score/smplockseq.h>
+
+struct _Thread_Control;
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+#if defined(RTEMS_SMP)
+/**
+ * @brief State to indicate potential help for other threads.
+ *
+ * @dot
+ * digraph state {
+ *   y [label="HELP YOURSELF"];
+ *   ao [label="HELP ACTIVE OWNER"];
+ *   ar [label="HELP ACTIVE RIVAL"];
+ *
+ *   y -> ao [label="obtain"];
+ *   y -> ar [label="wait for obtain"];
+ *   ao -> y [label="last release"];
+ *   ao -> r [label="wait for obtain"];
+ *   ar -> r [label="timeout"];
+ *   ar -> ao [label="timeout"];
+ * }
+ * @enddot
+ */
+typedef enum {
+  /**
+   * @brief This scheduler node is solely used by the owner thread.
+   *
+   * This thread owns no resources using a helping protocol and thus does not
+   * take part in the scheduler helping protocol.  No help will be provided for
+   * other thread.
+   */
+  SCHEDULER_HELP_YOURSELF,
+
+  /**
+   * @brief This scheduler node is owned by a thread actively owning a resource.
+   *
+   * This scheduler node can be used to help out threads.
+   *
+   * In case this scheduler node changes its state from ready to scheduled and
+   * the thread executes using another node, then an idle thread will be
+   * provided as a user of this node to temporarily execute on behalf of the
+   * owner thread.  Thus lower priority threads are denied access to the
+   * processors of this scheduler instance.
+   *
+   * In case a thread actively owning a resource performs a blocking operation,
+   * then an idle thread will be used also in case this node is in the
+   * scheduled state.
+   */
+  SCHEDULER_HELP_ACTIVE_OWNER,
+
+  /**
+   * @brief This scheduler node is owned by a thread actively obtaining a
+   * resource currently owned by another thread.
+   *
+   * This scheduler node can be used to help out threads.
+   *
+   * The thread owning this node is ready and will give away its processor in
+   * case the thread owning the resource asks for help.
+   */
+  SCHEDULER_HELP_ACTIVE_RIVAL,
+
+  /**
+   * @brief This scheduler node is owned by a thread obtaining a
+   * resource currently owned by another thread.
+   *
+   * This scheduler node can be used to help out threads.
+   *
+   * The thread owning this node is blocked.
+   */
+  SCHEDULER_HELP_PASSIVE
+} Scheduler_Help_state;
+#endif
+
+/**
+ * @brief Scheduler node for per-thread data.
+ */
+typedef struct {
+#if defined(RTEMS_SMP)
+  /**
+   * @brief Chain node for usage in various scheduler data structures.
+   *
+   * Strictly this is the wrong place for this field since the data structures
+   * to manage scheduler nodes belong to the particular scheduler
+   * implementation.  Currently all SMP scheduler implementations use chains.
+   * The node is here to simplify things, just like the object node in the
+   * thread control block.  It may be replaced with a union to add a red-black
+   * tree node in the future.
+   */
+  Chain_Node Node;
+
+  /**
+   * @brief The thread using this node.
+   */
+  struct _Thread_Control *user;
+
+  /**
+   * @brief The help state of this node.
+   */
+  Scheduler_Help_state help_state;
+
+  /**
+   * @brief The thread owning this node.
+   */
+  struct _Thread_Control *owner;
+
+  /**
+   * @brief The idle thread claimed by this node in case the help state is
+   * SCHEDULER_HELP_ACTIVE_OWNER.
+   *
+   * Active owners will lend their own node to an idle thread in case they
+   * execute currently using another node or in case they perform a blocking
+   * operation.  This is necessary to ensure the priority ceiling protocols
+   * work across scheduler boundaries.
+   */
+  struct _Thread_Control *idle;
+
+  /**
+   * @brief The thread accepting help by this node in case the help state is
+   * not SCHEDULER_HELP_YOURSELF.
+   */
+  struct _Thread_Control *accepts_help;
+#endif
+
+  /**
+   * @brief The thread priority information used by the scheduler.
+   *
+   * The thread priority is manifest in two independent areas.  One area is the
+   * user visible thread priority along with a potential thread queue.  The
+   * other is the scheduler.  During a thread priority change, the user visible
+   * thread priority and the thread queue are first updated and the thread
+   * priority value here is changed.  Once this is done the scheduler is
+   * notified via the update priority operation, so that it can update its
+   * internal state and honour a new thread priority value.
+   */
+  struct {
+    /**
+     * @brief The thread priority value of this scheduler node.
+     *
+     * The producer of this value is _Thread_Change_priority().  The consumer
+     * is the scheduler via the unblock and update priority operations.
+     */
+    Priority_Control value;
+
+#if defined(RTEMS_SMP)
+    /**
+     * @brief Sequence lock to synchronize priority value updates.
+     */
+    SMP_sequence_lock_Control Lock;
+#endif
+
+    /**
+     * @brief In case a priority update is necessary and this is true, then
+     * enqueue the thread as the first of its priority group, otherwise enqueue
+     * the thread as the last of its priority group.
+     */
+    bool prepend_it;
+  } Priority;
+} Scheduler_Node;
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+#endif /* _RTEMS_SCORE_SCHEDULERNODE_H */