score: Multiprocessor Resource Sharing Protocol

Add basic support for the Multiprocessor Resource Sharing Protocol
(MrsP).

The Multiprocessor Resource Sharing Protocol (MrsP) is defined in A.
Burns and A.J.  Wellings, A Schedulability Compatible Multiprocessor
Resource Sharing Protocol - MrsP, Proceedings of the 25th Euromicro
Conference on Real-Time Systems (ECRTS 2013), July 2013.  It is a
generalization of the Priority Ceiling Protocol to SMP systems.  Each
MrsP semaphore uses a ceiling priority per scheduler instance.  These
ceiling priorities can be specified with rtems_semaphore_set_priority().
A task obtaining or owning a MrsP semaphore will execute with the
ceiling priority for its scheduler instance as specified by the MrsP
semaphore object.  Tasks waiting to get ownership of a MrsP semaphore
will not relinquish the processor voluntarily.  In case the owner of a
MrsP semaphore gets preempted it can ask all tasks waiting for this
semaphore to help out and temporarily borrow the right to execute on one
of their assigned processors.

The help out feature is not implemented with this patch.

1 files changed, 31 insertions, 0 deletions

diff --git a/cpukit/rtems/include/rtems/rtems/attrimpl.h b/cpukit/rtems/include/rtems/rtems/attrimpl.h
index 0f78c44672..a32c37096d 100644
--- a/cpukit/rtems/include/rtems/rtems/attrimpl.h
+++ b/cpukit/rtems/include/rtems/rtems/attrimpl.h
@@ -185,6 +185,23 @@ RTEMS_INLINE_ROUTINE bool _Attributes_Is_inherit_priority(
 }
 
 /**
+ * @brief Returns true if the attribute set has at most one protocol, and false
+ * otherwise.
+ *
+ * The protocols are RTEMS_INHERIT_PRIORITY, RTEMS_PRIORITY_CEILING and
+ * RTEMS_MULTIPROCESSOR_RESOURCE_SHARING.
+ */
+RTEMS_INLINE_ROUTINE bool _Attributes_Has_at_most_one_protocol(
+  rtems_attribute attribute_set
+)
+{
+  attribute_set &= RTEMS_INHERIT_PRIORITY | RTEMS_PRIORITY_CEILING
+    | RTEMS_MULTIPROCESSOR_RESOURCE_SHARING;
+
+  return ( attribute_set & ( attribute_set - 1 ) ) == 0;
+}
+
+/**
  *  @brief Checks if the priority ceiling attribute
  *  is enabled in the attribute_set
  *
@@ -199,6 +216,20 @@ RTEMS_INLINE_ROUTINE bool _Attributes_Is_priority_ceiling(
 }
 
 /**
+ *  @brief Checks if the Multiprocessor Resource Sharing Protocol attribute
+ *  is enabled in the attribute_set
+ *
+ *  This function returns TRUE if the Multiprocessor Resource Sharing Protocol
+ *  attribute is enabled in the attribute_set and FALSE otherwise.
+ */
+RTEMS_INLINE_ROUTINE bool _Attributes_Is_multiprocessor_resource_sharing(
+  rtems_attribute attribute_set
+)
+{
+  return ( attribute_set & RTEMS_MULTIPROCESSOR_RESOURCE_SHARING ) != 0;
+}
+
+/**
  *  @brief Checks if the barrier automatic release
  *  attribute is enabled in the attribute_set
  *