Re: [PATCH] linux/memcontrol.h: Remove duplicate struct declaration

[Michal Hocko]

On Tue 30-03-21 10:02:36, Wan Jiabing wrote:
> struct mem_cgroup is declared twice. One has been declared
> at forward struct declaration. Remove the duplicate.

Duplicate declaration shouldn't really cause any problems. You are right
that there is one which is independent on CONFIG_MEMCG so the below one
is not needed though. It would be great if the changelog mentioned that
so that.

> Signed-off-by: Wan Jiabing <wanjiabing@xxxxxxxx>

Acked-by: Michal Hocko <mhocko@xxxxxxxx>

> ---
>  include/linux/memcontrol.h | 2 --
>  1 file changed, 2 deletions(-)
> 
> diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
> index 0c04d39a7967..f0ae33a0f175 100644
> --- a/include/linux/memcontrol.h
> +++ b/include/linux/memcontrol.h
> @@ -1068,8 +1068,6 @@ void split_page_memcg(struct page *head, unsigned int nr);
>  #define MEM_CGROUP_ID_SHIFT	0
>  #define MEM_CGROUP_ID_MAX	0
>  
> -struct mem_cgroup;
> -
>  static inline struct mem_cgroup *page_memcg(struct page *page)
>  {
>  	return NULL;
> -- 
> 2.25.1

-- 
Michal Hocko
SUSE Labs