cds containers: lfqueue and lfstack: don't depend on a particular rcu flavor

[urcu.git] / urcu / rculfstack-static.h

diff --git a/urcu/rculfstack-static.h b/urcu/rculfstack-static.h
index 49e5ef4adf905530d82577544d35ae6e1602f895..7caf3c8c0d15f344170c33873f4cb6f4b4d107fa 100644 (file)
--- a/urcu/rculfstack-static.h
+++ b/urcu/rculfstack-static.h
@@ -33,21 +33,21 @@
 extern "C" {
 #endif
 
-void _rcu_lfs_node_init(struct rcu_lfs_node *node)
+void _cds_lfs_node_init_rcu(struct cds_lfs_node_rcu *node)
 {
 }
 
-void _rcu_lfs_init(struct rcu_lfs_stack *s)
+void _cds_lfs_init_rcu(struct cds_lfs_stack_rcu *s)
 {
        s->head = NULL;
 }
 
-void _rcu_lfs_push(struct rcu_lfs_stack *s, struct rcu_lfs_node *node)
+void _cds_lfs_push_rcu(struct cds_lfs_stack_rcu *s, struct cds_lfs_node_rcu *node)
 {
-       struct rcu_lfs_node *head = NULL;
+       struct cds_lfs_node_rcu *head = NULL;
 
        for (;;) {
-               struct rcu_lfs_node *old_head = head;
+               struct cds_lfs_node_rcu *old_head = head;
 
                node->next = head;
                /*
@@ -61,29 +61,33 @@ void _rcu_lfs_push(struct rcu_lfs_stack *s, struct rcu_lfs_node *node)
 }
 
 /*
+ * Should be called under rcu read-side lock.
+ *
  * The caller must wait for a grace period to pass before freeing the returned
- * node or modifying the rcu_lfs_node structure.
+ * node or modifying the cds_lfs_node_rcu structure.
  * Returns NULL if stack is empty.
  */
-struct rcu_lfs_node *
-_rcu_lfs_pop(struct rcu_lfs_stack *s)
+struct cds_lfs_node_rcu *
+_cds_lfs_pop_rcu(struct cds_lfs_stack_rcu *s)
 {
-       struct rcu_lfs_node *head = NULL;
-
        for (;;) {
-               struct rcu_lfs_node *old_head = head;
-               struct rcu_lfs_node *next;
+               struct cds_lfs_node_rcu *head;
 
-               if (head)
-                       next = head->next;
-               else
-                       next = NULL;
+               head = rcu_dereference(s->head);
+               if (head) {
+                       struct cds_lfs_node_rcu *next = rcu_dereference(head->next);
 
-               head = uatomic_cmpxchg(&s->head, old_head, next);
-               if (old_head == head)
-                       break;
+                       if (uatomic_cmpxchg(&s->head, head, next) == head) {
+                               return head;
+                       } else {
+                               /* Concurrent modification. Retry. */
+                               continue;
+                       }
+               } else {
+                       /* Empty stack */
+                       return NULL;
+               }
        }
-       return head;
 }
 
 #ifdef __cplusplus