}
/*
+ * 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 cds_lfs_node_rcu structure.
* Returns NULL if stack is empty.
for (;;) {
struct cds_lfs_node_rcu *head;
- rcu_read_lock();
head = rcu_dereference(s->head);
if (head) {
struct cds_lfs_node_rcu *next = rcu_dereference(head->next);
if (uatomic_cmpxchg(&s->head, head, next) == head) {
- rcu_read_unlock();
return head;
} else {
/* Concurrent modification. Retry. */
- rcu_read_unlock();
continue;
}
} else {
/* Empty stack */
- rcu_read_unlock();
return NULL;
}
}