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 <[email protected]>
Cc: Al Viro <[email protected]>
Cc: Andrey Vagin <[email protected]>
Cc: "Eric W. Biederman" <[email protected]>
Cc: David Howells <[email protected]>
Cc: Huang Ying <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Al Viro <[email protected]>
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 @@
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 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 @@
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 */
