io-wq: improve wq_list_add_tail()

Prepare nodes that we're going to add before actually linking them, it's
always safer and costs us nothing.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/f7e53f0c84c02ed6748c488ed0789b98f8cc6185.1628471125.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/fs/io-wq.h b/fs/io-wq.h
index 3999ee5..308af39 100644 (file)
--- a/fs/io-wq.h
+++ b/fs/io-wq.h
@@ -44,6 +44,7 @@ static inline void wq_list_add_after(struct io_wq_work_node *node,
 static inline void wq_list_add_tail(struct io_wq_work_node *node,
                                    struct io_wq_work_list *list)
 {
+       node->next = NULL;
        if (!list->first) {
                list->last = node;
                WRITE_ONCE(list->first, node);
@@ -51,7 +52,6 @@ static inline void wq_list_add_tail(struct io_wq_work_node *node,
                list->last->next = node;
                list->last = node;
        }
-       node->next = NULL;
 }
 
 static inline void wq_list_cut(struct io_wq_work_list *list,