Re: [PATCH 3/7] mm: memcontrol: privatize memcg_page_state query functions

From: Michal Hocko
Date: Thu Feb 04 2021 - 08:31:34 EST


On Tue 02-02-21 13:47:42, Johannes Weiner wrote:
> There are no users outside of the memory controller itself. The rest
> of the kernel cares either about node or lruvec stats.
>
> Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx>

Acked-by: Michal Hocko <mhocko@xxxxxxxx>

> ---
> include/linux/memcontrol.h | 44 --------------------------------------
> mm/memcontrol.c | 32 +++++++++++++++++++++++++++
> 2 files changed, 32 insertions(+), 44 deletions(-)
>
> diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
> index c7f387a6233e..20ecdfae3289 100644
> --- a/include/linux/memcontrol.h
> +++ b/include/linux/memcontrol.h
> @@ -867,39 +867,6 @@ struct mem_cgroup *lock_page_memcg(struct page *page);
> void __unlock_page_memcg(struct mem_cgroup *memcg);
> void unlock_page_memcg(struct page *page);
>
> -/*
> - * idx can be of type enum memcg_stat_item or node_stat_item.
> - * Keep in sync with memcg_exact_page_state().
> - */
> -static inline unsigned long memcg_page_state(struct mem_cgroup *memcg, int idx)
> -{
> - long x = atomic_long_read(&memcg->vmstats[idx]);
> -#ifdef CONFIG_SMP
> - if (x < 0)
> - x = 0;
> -#endif
> - return x;
> -}
> -
> -/*
> - * idx can be of type enum memcg_stat_item or node_stat_item.
> - * Keep in sync with memcg_exact_page_state().
> - */
> -static inline unsigned long memcg_page_state_local(struct mem_cgroup *memcg,
> - int idx)
> -{
> - long x = 0;
> - int cpu;
> -
> - for_each_possible_cpu(cpu)
> - x += per_cpu(memcg->vmstats_local->stat[idx], cpu);
> -#ifdef CONFIG_SMP
> - if (x < 0)
> - x = 0;
> -#endif
> - return x;
> -}
> -
> void __mod_memcg_state(struct mem_cgroup *memcg, int idx, int val);
>
> /* idx can be of type enum memcg_stat_item or node_stat_item */
> @@ -1337,17 +1304,6 @@ static inline void mem_cgroup_print_oom_group(struct mem_cgroup *memcg)
> {
> }
>
> -static inline unsigned long memcg_page_state(struct mem_cgroup *memcg, int idx)
> -{
> - return 0;
> -}
> -
> -static inline unsigned long memcg_page_state_local(struct mem_cgroup *memcg,
> - int idx)
> -{
> - return 0;
> -}
> -
> static inline void __mod_memcg_state(struct mem_cgroup *memcg,
> int idx,
> int nr)
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index 7e05a4ebf80f..2f97cb4cef6d 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -789,6 +789,38 @@ void __mod_memcg_state(struct mem_cgroup *memcg, int idx, int val)
> __this_cpu_write(memcg->vmstats_percpu->stat[idx], x);
> }
>
> +/*
> + * idx can be of type enum memcg_stat_item or node_stat_item.
> + * Keep in sync with memcg_exact_page_state().
> + */
> +static unsigned long memcg_page_state(struct mem_cgroup *memcg, int idx)
> +{
> + long x = atomic_long_read(&memcg->vmstats[idx]);
> +#ifdef CONFIG_SMP
> + if (x < 0)
> + x = 0;
> +#endif
> + return x;
> +}
> +
> +/*
> + * idx can be of type enum memcg_stat_item or node_stat_item.
> + * Keep in sync with memcg_exact_page_state().
> + */
> +static unsigned long memcg_page_state_local(struct mem_cgroup *memcg, int idx)
> +{
> + long x = 0;
> + int cpu;
> +
> + for_each_possible_cpu(cpu)
> + x += per_cpu(memcg->vmstats_local->stat[idx], cpu);
> +#ifdef CONFIG_SMP
> + if (x < 0)
> + x = 0;
> +#endif
> + return x;
> +}
> +
> static struct mem_cgroup_per_node *
> parent_nodeinfo(struct mem_cgroup_per_node *pn, int nid)
> {
> --
> 2.30.0
>

--
Michal Hocko
SUSE Labs