Re: [RFC][PATCH 4/6] memcg: swap cgroup for remembering account

Daisuke Nishimura
2008-11-12T04:17:01Z

> +/**
> + * lookup_swap_cgroup - lookup mem_cgroup tied to swap entry
> + * @ent: swap entry to be looked up.
> + *
> + * Returns pointer to mem_cgroup at success. NULL at failure.
> + */
> +struct mem_cgroup *lookup_swap_cgroup(swp_entry_t ent)
> +{
> + int type = swp_type(ent);
> + unsigned long flags;
> + unsigned long offset = swp_offset(ent);
> + unsigned long idx = offset / SC_PER_PAGE;
> + unsigned long pos = offset & SC_POS_MASK;
> + struct swap_cgroup_ctrl *ctrl;
> + struct page *mappage;
> + struct swap_cgroup *sc;
> + struct mem_cgroup *ret;
> +
> + if (!do_swap_account)
> + return NULL;
> +
> + ctrl = &swap_cgroup_ctrl[type];
> +
> + mappage = ctrl->map[idx];
> +
> + spin_lock_irqsave(&ctrl->lock, flags);
> + sc = kmap_atomic(mappage, KM_USER0);
> + sc += pos;
> + ret = sc->val;
> + kunmap_atomic(mapppage, KM_USER0);
s/mapppage/mappage

I don't know why I didn't notice this while testing previous version.

Thanks,
Daisuke Nishimura.

> + spin_unlock_irqrestore(&ctrl->lock, flags);
> + return ret;
> +}
> +