Re: [PATCH] cgroup: Remove unused css_put_many().

[Waiman Long <llong@redhat.com>]

On 8/6/25 4:04 AM, Julian Sun wrote:
> Remove css_put_many() as it's never called by any function.

It isn't currently used doesn't mean that it will not be used in the 
future. We have css_get_many() that is used in memcontrol.c. For 
symmetry, we should have a corresponding css_put_many(). Also there is 
little cost in keeping this little helper function around.

Cheers,
Longman

>
> Signed-off-by: Julian Sun <sunjunchao@bytedance.com>
> ---
>   include/linux/cgroup.h        |  1 -
>   include/linux/cgroup_refcnt.h | 15 ---------------
>   2 files changed, 16 deletions(-)
>
> diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h
> index b18fb5fcb38e..2e232eb8c897 100644
> --- a/include/linux/cgroup.h
> +++ b/include/linux/cgroup.h
> @@ -322,7 +322,6 @@ void css_get_many(struct cgroup_subsys_state *css, unsigned int n);
>   bool css_tryget(struct cgroup_subsys_state *css);
>   bool css_tryget_online(struct cgroup_subsys_state *css);
>   void css_put(struct cgroup_subsys_state *css);
> -void css_put_many(struct cgroup_subsys_state *css, unsigned int n);
>   #else
>   #define CGROUP_REF_FN_ATTRS	static inline
>   #define CGROUP_REF_EXPORT(fn)
> diff --git a/include/linux/cgroup_refcnt.h b/include/linux/cgroup_refcnt.h
> index 2eea0a69ecfc..1cede70a928c 100644
> --- a/include/linux/cgroup_refcnt.h
> +++ b/include/linux/cgroup_refcnt.h
> @@ -79,18 +79,3 @@ void css_put(struct cgroup_subsys_state *css)
>   		percpu_ref_put(&css->refcnt);
>   }
>   CGROUP_REF_EXPORT(css_put)
> -
> -/**
> - * css_put_many - put css references
> - * @css: target css
> - * @n: number of references to put
> - *
> - * Put references obtained via css_get() and css_tryget_online().
> - */
> -CGROUP_REF_FN_ATTRS
> -void css_put_many(struct cgroup_subsys_state *css, unsigned int n)
> -{
> -	if (!(css->flags & CSS_NO_REF))
> -		percpu_ref_put_many(&css->refcnt, n);
> -}
> -CGROUP_REF_EXPORT(css_put_many)