opal: add recursive mutex

This new class is the same as the opal_mutex_t class but has a
different constructor. This constructor adds the recursive flag to the
mutex attributes for the lock. This class can be used where there may
be re-enty into the lock from within the same thread.

Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>

opal/threads/mutex.c

@@ -72,3 +72,29 @@ OBJ_CLASS_INSTANCE(opal_mutex_t,
                    opal_object_t,
                    opal_mutex_construct,
                    opal_mutex_destruct);
+
+static void opal_recursive_mutex_construct(opal_recursive_mutex_t *m)
+{
+    pthread_mutexattr_t attr;
+    pthread_mutexattr_init(&attr);
+
+#if OPAL_ENABLE_DEBUG
+    m->m_lock_debug = 0;
+    m->m_lock_file = NULL;
+    m->m_lock_line = 0;
+#endif
+
+    pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE);
+
+    pthread_mutex_init(&m->m_lock_pthread, &attr);
+    pthread_mutexattr_destroy(&attr);
+
+#if OPAL_HAVE_ATOMIC_SPINLOCKS
+    opal_atomic_init( &m->m_lock_atomic, OPAL_ATOMIC_UNLOCKED );
+#endif
+}
+
+OBJ_CLASS_INSTANCE(opal_recursive_mutex_t,
+                   opal_object_t,
+                   opal_recursive_mutex_construct,
+                   opal_mutex_destruct);

opal/threads/mutex.h

@@ -50,7 +50,7 @@ OPAL_DECLSPEC extern bool opal_uses_threads;
  * Opaque mutex object
  */
 typedef struct opal_mutex_t opal_mutex_t;
-
+typedef struct opal_mutex_t opal_recursive_mutex_t;
 
 /**
  * Try to acquire a mutex.

opal/threads/mutex_unix.h

@@ -61,6 +61,7 @@ struct opal_mutex_t {
     opal_atomic_lock_t m_lock_atomic;
 };
 OPAL_DECLSPEC OBJ_CLASS_DECLARATION(opal_mutex_t);
+OPAL_DECLSPEC OBJ_CLASS_DECLARATION(opal_recursive_mutex_t);
 
 /************************************************************************
  *