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Subject: Re: [PATCH] list: Remove unnecessary WRITE_ONCE()
From:   Alan Huang <mmpgouride@gmail.com>
In-Reply-To: <20230619090336.145738-1-mmpgouride@gmail.com>
Date:   Wed, 21 Jun 2023 20:12:55 +0800
Cc:     Eric Dumazet <edumazet@google.com>, linux-kernel@vger.kernel.org
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Message-Id: <4B653A92-5FD0-4E38-9F86-AEFE5B86AADA@gmail.com>
References: <20230619090336.145738-1-mmpgouride@gmail.com>
To:     paulmck@kernel.org
Precedence: bulk

Hi Paul,

Looks like you missed this one?

Thanks,
Alan

> 2023=E5=B9=B46=E6=9C=8819=E6=97=A5 17:03=EF=BC=8CAlan Huang =
<mmpgouride@gmail.com> =E5=86=99=E9=81=93=EF=BC=9A
>=20
> 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().
>=20
> Signed-off-by: Alan Huang <mmpgouride@gmail.com>
> ---
> include/linux/list.h | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>=20
> 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 =3D h->first;
> - WRITE_ONCE(n->next, first);
> + n->next =3D 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 =3D 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 =3D prev->next;
> + prev->next =3D n;
> WRITE_ONCE(n->pprev, &prev->next);
>=20
> if (n->next)
> --=20
> 2.34.1
>=20