io-wq: add helper to merge two wq_lists

add a helper to merge two wq_lists, it will be useful in the next
patches.

Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Hao Xu <haoxu@linux.alibaba.com>
Link: https://lore.kernel.org/r/20211207093951.247840-2-haoxu@linux.alibaba.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Hao Xu 2021-12-07 17:39:47 +08:00 committed by Jens Axboe
parent a90c8bf659
commit 24115c4e95

View file

@ -52,6 +52,28 @@ static inline void wq_list_add_after(struct io_wq_work_node *node,
list->last = node;
}
/**
* wq_list_merge - merge the second list to the first one.
* @list0: the first list
* @list1: the second list
* Return the first node after mergence.
*/
static inline struct io_wq_work_node *wq_list_merge(struct io_wq_work_list *list0,
struct io_wq_work_list *list1)
{
struct io_wq_work_node *ret;
if (!list0->first) {
ret = list1->first;
} else {
ret = list0->first;
list0->last->next = list1->first;
}
INIT_WQ_LIST(list0);
INIT_WQ_LIST(list1);
return ret;
}
static inline void wq_list_add_tail(struct io_wq_work_node *node,
struct io_wq_work_list *list)
{