diff options
Diffstat (limited to 'include/linux/list.h')
| -rw-r--r-- | include/linux/list.h | 28 |
1 files changed, 16 insertions, 12 deletions
diff --git a/include/linux/list.h b/include/linux/list.h index 8392884a2977..d167b5d7c0ac 100644 --- a/include/linux/list.h +++ b/include/linux/list.h @@ -1,6 +1,7 @@ #ifndef _LINUX_LIST_H #define _LINUX_LIST_H +#include <linux/types.h> #include <linux/stddef.h> #include <linux/poison.h> #include <linux/prefetch.h> @@ -16,10 +17,6 @@ * using the generic single-entry routines. */ -struct list_head { - struct list_head *next, *prev; -}; - #define LIST_HEAD_INIT(name) { &(name), &(name) } #define LIST_HEAD(name) \ @@ -544,6 +541,21 @@ static inline void list_splice_tail_init(struct list_head *list, &pos->member != (head); \ pos = n, n = list_entry(n->member.prev, typeof(*n), member)) +/** + * list_safe_reset_next - reset a stale list_for_each_entry_safe loop + * @pos: the loop cursor used in the list_for_each_entry_safe loop + * @n: temporary storage used in list_for_each_entry_safe + * @member: the name of the list_struct within the struct. + * + * list_safe_reset_next is not safe to use in general if the list may be + * modified concurrently (eg. the lock is dropped in the loop body). An + * exception to this is if the cursor element (pos) is pinned in the list, + * and list_safe_reset_next is called after re-taking the lock and before + * completing the current iteration of the loop body. + */ +#define list_safe_reset_next(pos, n, member) \ + n = list_entry(pos->member.next, typeof(*pos), member) + /* * Double linked lists with a single pointer list head. * Mostly useful for hash tables where the two pointer list head is @@ -551,14 +563,6 @@ static inline void list_splice_tail_init(struct list_head *list, * You lose the ability to access the tail in O(1). */ -struct hlist_head { - struct hlist_node *first; -}; - -struct hlist_node { - struct hlist_node *next, **pprev; -}; - #define HLIST_HEAD_INIT { .first = NULL } #define HLIST_HEAD(name) struct hlist_head name = { .first = NULL } #define INIT_HLIST_HEAD(ptr) ((ptr)->first = NULL) |