From e9a17bd73a29e5323c37ec5ffe50fc0e825d3d03 Mon Sep 17 00:00:00 2001 From: Oleg Nesterov Date: Mon, 8 Jul 2013 14:24:19 -0700 Subject: [PATCH] llist: llist_add() can use llist_add_batch() 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 Cc: Al Viro Cc: Andrey Vagin Cc: "Eric W. Biederman" Cc: David Howells Cc: Huang Ying Cc: Peter Zijlstra Signed-off-by: Andrew Morton Signed-off-by: Al Viro --- include/linux/llist.h | 14 ++++---------- 1 file changed, 4 insertions(+), 10 deletions(-) diff --git a/include/linux/llist.h b/include/linux/llist.h index 3e2b969d68f6..cdaa7f023899 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 */ -- 2.30.2