Re: [PATCH] list: Remove unnecessary WRITE_ONCE()

From: Alan Huang
Date: Wed Jun 21 2023 - 08:13:26 EST


Hi Paul,

Looks like you missed this one?

Thanks,
Alan

> 2023年6月19日 17:03,Alan Huang <mmpgouride@xxxxxxxxx> 写道:
>
> Commit c54a2744497d("list: Add hlist_unhashed_lockless()") added
> various WRITE_ONCE() to pair with the READ_ONCE() in
> hlist_unhashed_lockless(), but there is no need to protect
> ->next with WRITE_ONCE(). Therefore, this commit removes those
> unnecessary WRITE_ONCE().
>
> Signed-off-by: Alan Huang <mmpgouride@xxxxxxxxx>
> ---
> include/linux/list.h | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/include/linux/list.h b/include/linux/list.h
> index f10344dbad..ac366958ea 100644
> --- a/include/linux/list.h
> +++ b/include/linux/list.h
> @@ -940,7 +940,7 @@ static inline void hlist_del_init(struct hlist_node *n)
> static inline void hlist_add_head(struct hlist_node *n, struct hlist_head *h)
> {
> struct hlist_node *first = h->first;
> - WRITE_ONCE(n->next, first);
> + n->next = first;
> if (first)
> WRITE_ONCE(first->pprev, &n->next);
> WRITE_ONCE(h->first, n);
> @@ -956,7 +956,7 @@ static inline void hlist_add_before(struct hlist_node *n,
> struct hlist_node *next)
> {
> WRITE_ONCE(n->pprev, next->pprev);
> - WRITE_ONCE(n->next, next);
> + n->next = next;
> WRITE_ONCE(next->pprev, &n->next);
> WRITE_ONCE(*(n->pprev), n);
> }
> @@ -969,8 +969,8 @@ static inline void hlist_add_before(struct hlist_node *n,
> static inline void hlist_add_behind(struct hlist_node *n,
> struct hlist_node *prev)
> {
> - WRITE_ONCE(n->next, prev->next);
> - WRITE_ONCE(prev->next, n);
> + n->next = prev->next;
> + prev->next = n;
> WRITE_ONCE(n->pprev, &prev->next);
>
> if (n->next)
> --
> 2.34.1
>