llist_add(new, head) can simply use llist_add_batch(new, new, head), no need to duplicate the code.
This obviously uninlines llist_add() and to me this is a win. But we can make llist_add_batch() inline if this is desirable, in this case gcc can notice that new_first == new_last if the caller is llist_add(). Signed-off-by: Oleg Nesterov <o...@redhat.com> --- include/linux/llist.h | 14 ++++---------- 1 files changed, 4 insertions(+), 10 deletions(-) diff --git a/include/linux/llist.h b/include/linux/llist.h index 3e2b969..cdaa7f0 100644 --- a/include/linux/llist.h +++ b/include/linux/llist.h @@ -142,6 +142,9 @@ static inline struct llist_node *llist_next(struct llist_node *node) return node->next; } +extern bool llist_add_batch(struct llist_node *new_first, + struct llist_node *new_last, + struct llist_head *head); /** * llist_add - add a new entry * @new: new entry to be added @@ -151,13 +154,7 @@ static inline struct llist_node *llist_next(struct llist_node *node) */ static inline bool llist_add(struct llist_node *new, struct llist_head *head) { - struct llist_node *first; - - do { - new->next = first = ACCESS_ONCE(head->first); - } while (cmpxchg(&head->first, first, new) != first); - - return !first; + return llist_add_batch(new, new, head); } /** @@ -173,9 +170,6 @@ static inline struct llist_node *llist_del_all(struct llist_head *head) return xchg(&head->first, NULL); } -extern bool llist_add_batch(struct llist_node *new_first, - struct llist_node *new_last, - struct llist_head *head); extern struct llist_node *llist_del_first(struct llist_head *head); #endif /* LLIST_H */ -- 1.5.5.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/