diff options
Diffstat (limited to 'lib/llist.c')
| -rw-r--r-- | lib/llist.c | 40 |
1 files changed, 28 insertions, 12 deletions
diff --git a/lib/llist.c b/lib/llist.c index 700cff77a38..f76196d0740 100644 --- a/lib/llist.c +++ b/lib/llist.c @@ -23,11 +23,10 @@ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include <linux/kernel.h> -#include <linux/module.h> +#include <linux/export.h> #include <linux/interrupt.h> #include <linux/llist.h> -#include <asm/system.h> /** * llist_add_batch - add several linked entries in batch @@ -40,18 +39,13 @@ 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); @@ -87,3 +81,25 @@ struct llist_node *llist_del_first(struct llist_head *head) 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); |