bool llist_add_batch(struct llist_node *new_first, struct llist_node *new_last,
struct llist_head *head)
{
- struct llist_node *entry, *old_entry;
+ struct llist_node *first;
- entry = head->first;
- for (;;) {
- old_entry = entry;
- new_last->next = entry;
- entry = cmpxchg(&head->first, old_entry, new_first);
- if (entry == old_entry)
- break;
- }
+ do {
+ new_last->next = first = ACCESS_ONCE(head->first);
+ } while (cmpxchg(&head->first, first, new_first) != first);
- return old_entry == NULL;
+ return !first;
}
EXPORT_SYMBOL_GPL(llist_add_batch);
return entry;
}
EXPORT_SYMBOL_GPL(llist_del_first);
+
+/**
+ * llist_reverse_order - reverse order of a llist chain
+ * @head: first item of the list to be reversed
+ *
+ * Reverse the order of a chain of llist entries and return the
+ * new first entry.
+ */
+struct llist_node *llist_reverse_order(struct llist_node *head)
+{
+ struct llist_node *new_head = NULL;
+
+ while (head) {
+ struct llist_node *tmp = head;
+ head = head->next;
+ tmp->next = new_head;
+ new_head = tmp;
+ }
+
+ return new_head;
+}
+EXPORT_SYMBOL_GPL(llist_reverse_order);