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Date: Thu, 14 Jun 2012 16:54:14 +0800
From: Li Zefan <lizefan@huawei.com>
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To: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
CC: <linux-mm@kvack.org>, <kamezawa.hiroyu@jp.fujitsu.com>, <dhillf@gmail.com>,
        <rientjes@google.com>, <mhocko@suse.cz>, <akpm@linux-foundation.org>,
        <hannes@cmpxchg.org>, <linux-kernel@vger.kernel.org>,
        <cgroups@vger.kernel.org>
Subject: Re: [PATCH -V9 09/15] mm/hugetlb: Add new HugeTLB cgroup
References: <1339583254-895-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <1339583254-895-10-git-send-email-aneesh.kumar@linux.vnet.ibm.com>
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> +static inline

> +struct hugetlb_cgroup *hugetlb_cgroup_from_css(struct cgroup_subsys_state *s)
> +{
> +	if (s)


Neither cgroup_subsys_state() or task_subsys_state() will ever return NULL,
so here 's' won't be NULL.

> +		return container_of(s, struct hugetlb_cgroup, css);
> +	return NULL;
> +}
> +
> +static inline
> +struct hugetlb_cgroup *hugetlb_cgroup_from_cgroup(struct cgroup *cgroup)
> +{
> +	return hugetlb_cgroup_from_css(cgroup_subsys_state(cgroup,
> +							   hugetlb_subsys_id));
> +}
> +
> +static inline
> +struct hugetlb_cgroup *hugetlb_cgroup_from_task(struct task_struct *task)
> +{
> +	return hugetlb_cgroup_from_css(task_subsys_state(task,
> +							 hugetlb_subsys_id));
> +}