Re: [PATCH 4/8] mm: memcontrol: prepare for unified hierarchy socket accounting

Michal Hocko
2015-10-23T12:39:36Z

On Thu 22-10-15 00:21:32, Johannes Weiner wrote:
> The unified hierarchy memory controller will account socket
> memory. Move the infrastructure functions accordingly.
>
> Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>

Acked-by: Michal Hocko <mhocko@suse.com>

> ---
> mm/memcontrol.c | 136 ++++++++++++++++++++++++++++----------------------------
> 1 file changed, 68 insertions(+), 68 deletions(-)
>
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index c41e6d7..3789050 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -287,74 +287,6 @@ static inline struct mem_cgroup *mem_cgroup_from_id(unsigned short id)
> return mem_cgroup_from_css(css);
> }
>
> -/* Writing them here to avoid exposing memcg's inner layout */
> -#if defined(CONFIG_INET) && defined(CONFIG_MEMCG_KMEM)
> -
> -DEFINE_STATIC_KEY_FALSE(mem_cgroup_sockets);
> -
> -void sock_update_memcg(struct sock *sk)
> -{
> - struct mem_cgroup *memcg;
> - /*
> - * Socket cloning can throw us here with sk_cgrp already
> - * filled. It won't however, necessarily happen from
> - * process context. So the test for root memcg given
> - * the current task's memcg won't help us in this case.
> - *
> - * Respecting the original socket's memcg is a better
> - * decision in this case.
> - */
> - if (sk->sk_memcg) {
> - BUG_ON(mem_cgroup_is_root(sk->sk_memcg));
> - css_get(&sk->sk_memcg->css);
> - return;
> - }
> -
> - rcu_read_lock();
> - memcg = mem_cgroup_from_task(current);
> - if (css_tryget_online(&memcg->css))
> - sk->sk_memcg = memcg;
> - rcu_read_unlock();
> -}
> -EXPORT_SYMBOL(sock_update_memcg);
> -
> -void sock_release_memcg(struct sock *sk)
> -{
> - if (sk->sk_memcg)
> - css_put(&sk->sk_memcg->css);
> -}
> -
> -/**
> - * mem_cgroup_charge_skmem - charge socket memory
> - * @memcg: memcg to charge
> - * @nr_pages: number of pages to charge
> - *
> - * Charges @nr_pages to @memcg. Returns %true if the charge fit within
> - * the memcg's configured limit, %false if the charge had to be forced.
> - */
> -bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages)
> -{
> - struct page_counter *counter;
> -
> - if (page_counter_try_charge(&memcg->skmem, nr_pages, &counter))
> - return true;
> -
> - page_counter_charge(&memcg->skmem, nr_pages);
> - return false;
> -}
> -
> -/**
> - * mem_cgroup_uncharge_skmem - uncharge socket memory
> - * @memcg: memcg to uncharge
> - * @nr_pages: number of pages to uncharge
> - */
> -void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages)
> -{
> - page_counter_uncharge(&memcg->skmem, nr_pages);
> -}
> -
> -#endif
> -
> #ifdef CONFIG_MEMCG_KMEM
> /*
> * This will be the memcg's index in each cache's ->memcg_params.memcg_caches.
> @@ -5521,6 +5453,74 @@ void mem_cgroup_replace_page(struct page *oldpage, struct page *newpage)
> commit_charge(newpage, memcg, true);
> }
>
> +/* Writing them here to avoid exposing memcg's inner layout */
> +#if defined(CONFIG_INET) && defined(CONFIG_MEMCG_KMEM)
> +
> +DEFINE_STATIC_KEY_FALSE(mem_cgroup_sockets);
> +
> +void sock_update_memcg(struct sock *sk)
> +{
> + struct mem_cgroup *memcg;
> + /*
> + * Socket cloning can throw us here with sk_cgrp already
> + * filled. It won't however, necessarily happen from
> + * process context. So the test for root memcg given
> + * the current task's memcg won't help us in this case.
> + *
> + * Respecting the original socket's memcg is a better
> + * decision in this case.
> + */
> + if (sk->sk_memcg) {
> + BUG_ON(mem_cgroup_is_root(sk->sk_memcg));
> + css_get(&sk->sk_memcg->css);
> + return;
> + }
> +
> + rcu_read_lock();
> + memcg = mem_cgroup_from_task(current);
> + if (css_tryget_online(&memcg->css))
> + sk->sk_memcg = memcg;
> + rcu_read_unlock();
> +}
> +EXPORT_SYMBOL(sock_update_memcg);
> +
> +void sock_release_memcg(struct sock *sk)
> +{
> + if (sk->sk_memcg)
> + css_put(&sk->sk_memcg->css);
> +}
> +
> +/**
> + * mem_cgroup_charge_skmem - charge socket memory
> + * @memcg: memcg to charge
> + * @nr_pages: number of pages to charge
> + *
> + * Charges @nr_pages to @memcg. Returns %true if the charge fit within
> + * the memcg's configured limit, %false if the charge had to be forced.
> + */
> +bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages)
> +{
> + struct page_counter *counter;
> +
> + if (page_counter_try_charge(&memcg->skmem, nr_pages, &counter))
> + return true;
> +
> + page_counter_charge(&memcg->skmem, nr_pages);
> + return false;
> +}
> +
> +/**
> + * mem_cgroup_uncharge_skmem - uncharge socket memory
> + * @memcg: memcg to uncharge
> + * @nr_pages: number of pages to uncharge
> + */
> +void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages)
> +{
> + page_counter_uncharge(&memcg->skmem, nr_pages);
> +}
> +
> +#endif
> +
> /*
> * subsys_initcall() for memory controller.
> *
> --
> 2.6.1

--
Michal Hocko
SUSE Labs