X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;ds=sidebyside;f=urcu%2Frculist.h;h=9a01dad2c8930f882763585d9ffc8f3c71e8d307;hb=2e1ced1f1ec38b5c9e85fe407a6e8390b9ac6416;hp=3604a96d0619d082ef7c3c2d46a4cff421c04c2e;hpb=bdffa73aa208ad5f1e5b3a3cb6cbf86ac6996559;p=userspace-rcu.git

diff --git a/urcu/rculist.h b/urcu/rculist.h
index 3604a96..9a01dad 100644
--- a/urcu/rculist.h
+++ b/urcu/rculist.h
@@ -29,32 +29,47 @@
 #include <urcu/arch.h>
 #include <urcu-pointer.h>
 
-/* Add new element at the head of the list.
- */
-static inline void cds_list_add_rcu(struct cds_list_head *newp, struct cds_list_head *head)
+/* Add new element at the head of the list. */
+static inline
+void cds_list_add_rcu(struct cds_list_head *newp, struct cds_list_head *head)
 {
 	newp->next = head->next;
 	newp->prev = head;
-	cmm_smp_wmb();
-	head->next->prev = newp;
-	head->next = newp;
+	rcu_assign_pointer(head->next->prev, newp);
+	CMM_STORE_SHARED(head->next, newp);
+}
+
+/* Add new element at the tail of the list. */
+static inline
+void cds_list_add_tail_rcu(struct cds_list_head *newp,
+		struct cds_list_head *head)
+{
+	newp->next = head;
+	newp->prev = head->prev;
+	rcu_assign_pointer(head->prev->next, newp);
+	CMM_STORE_SHARED(head->prev, newp);
 }
 
-/* replace an old entry atomically.
+/*
+ * Replace an old entry atomically with respect to concurrent RCU
+ * traversal. Mutual exclusion against concurrent updates is required
+ * though.
  */
-static inline void cds_list_replace_rcu(struct cds_list_head *old, struct cds_list_head *_new)
+static inline
+void cds_list_replace_rcu(struct cds_list_head *old, struct cds_list_head *_new)
 {
 	_new->next = old->next;
 	_new->prev = old->prev;
 	rcu_assign_pointer(_new->prev->next, _new);
-	_new->next->prev = _new;
+	CMM_STORE_SHARED(_new->next->prev, _new);
 }
 
 /* Remove element from list. */
-static inline void cds_list_del_rcu(struct cds_list_head *elem)
+static inline
+void cds_list_del_rcu(struct cds_list_head *elem)
 {
-	elem->next->prev = elem->prev;
-	elem->prev->next = elem->next;
+	CMM_STORE_SHARED(elem->next->prev, elem->prev);
+	CMM_STORE_SHARED(elem->prev->next, elem->next);
 }
 
 /*
@@ -64,15 +79,14 @@ static inline void cds_list_del_rcu(struct cds_list_head *elem)
 
 /* Iterate forward over the elements of the list.  */
 #define cds_list_for_each_rcu(pos, head) \
-  for (pos = rcu_dereference((head)->next); pos != (head); \
-       pos = rcu_dereference(pos->next))
+	for (pos = rcu_dereference((head)->next); pos != (head); \
+		pos = rcu_dereference(pos->next))
 
 
-/* Iterate through elements of the list.
- */
-#define cds_list_for_each_entry_rcu(pos, head, member)				\
-	for (pos = cds_list_entry(rcu_dereference((head)->next), __typeof__(*pos), member);	\
-	     &pos->member != (head);					\
-	     pos = cds_list_entry(rcu_dereference(pos->member.next), __typeof__(*pos), member))
+/* Iterate through elements of the list. */
+#define cds_list_for_each_entry_rcu(pos, head, member) \
+	for (pos = cds_list_entry(rcu_dereference((head)->next), __typeof__(*pos), member); \
+		&pos->member != (head); \
+		pos = cds_list_entry(rcu_dereference(pos->member.next), __typeof__(*pos), member))
 
 #endif	/* _URCU_RCULIST_H */