We alredy have list_first_entry(), it makes sense to also add list_last_entry() for consistency. And we use both helpers in in list_for_each_*().
Signed-off-by: Oleg Nesterov <[email protected]> --- include/linux/list.h | 19 +++++++++++++++---- 1 files changed, 15 insertions(+), 4 deletions(-) diff --git a/include/linux/list.h b/include/linux/list.h index c88a591..ef95941 100644 --- a/include/linux/list.h +++ b/include/linux/list.h @@ -362,6 +362,17 @@ static inline void list_splice_tail_init(struct list_head *list, list_entry((ptr)->next, type, member) /** + * list_last_entry - get the last element from a list + * @ptr: the list head to take the element from. + * @type: the type of the struct this is embedded in. + * @member: the name of the list_struct within the struct. + * + * Note, that list is expected to be not empty. + */ +#define list_last_entry(ptr, type, member) \ + list_entry((ptr)->prev, type, member) + +/** * list_first_entry_or_null - get the first element from a list * @ptr: the list head to take the element from. * @type: the type of the struct this is embedded in. @@ -432,7 +443,7 @@ static inline void list_splice_tail_init(struct list_head *list, * @member: the name of the list_struct within the struct. */ #define list_for_each_entry(pos, head, member) \ - for (pos = list_entry((head)->next, typeof(*pos), member); \ + for (pos = list_first_entry(head, typeof(*pos), member); \ &pos->member != (head); \ pos = list_next_entry(pos, member)) @@ -443,7 +454,7 @@ static inline void list_splice_tail_init(struct list_head *list, * @member: the name of the list_struct within the struct. */ #define list_for_each_entry_reverse(pos, head, member) \ - for (pos = list_entry((head)->prev, typeof(*pos), member); \ + for (pos = list_last_entry(head, typeof(*pos), member); \ &pos->member != (head); \ pos = list_prev_entry(pos, member)) @@ -506,7 +517,7 @@ static inline void list_splice_tail_init(struct list_head *list, * @member: the name of the list_struct within the struct. */ #define list_for_each_entry_safe(pos, n, head, member) \ - for (pos = list_entry((head)->next, typeof(*pos), member), \ + for (pos = list_first_entry(head, typeof(*pos), member), \ n = list_next_entry(pos, member); \ &pos->member != (head); \ pos = n, n = list_next_entry(n, member)) @@ -553,7 +564,7 @@ static inline void list_splice_tail_init(struct list_head *list, * of list entry. */ #define list_for_each_entry_safe_reverse(pos, n, head, member) \ - for (pos = list_entry((head)->prev, typeof(*pos), member), \ + for (pos = list_last_entry(head, typeof(*pos), member), \ n = list_prev_entry(pos, member); \ &pos->member != (head); \ pos = n, n = list_prev_entry(n, member)) -- 1.5.5.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
