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Date:   Mon, 18 Oct 2021 09:35:53 +0200
From:   Oscar Salvador <osalvador@suse.de>
To:     Mike Kravetz <mike.kravetz@oracle.com>
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        David Hildenbrand <david@redhat.com>,
        Michal Hocko <mhocko@suse.com>, Zi Yan <ziy@nvidia.com>,
        Muchun Song <songmuchun@bytedance.com>,
        Naoya Horiguchi <naoya.horiguchi@linux.dev>,
        David Rientjes <rientjes@google.com>,
        "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com>,
        Nghia Le <nghialm78@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH v4 1/5] hugetlb: add demote hugetlb page sysfs interfaces
Message-ID: <20211018073552.GA11960@linux>
References: <20211007181918.136982-1-mike.kravetz@oracle.com>
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On Fri, Oct 08, 2021 at 01:24:28PM -0700, Mike Kravetz wrote:
> In general, the resize_lock prevents unexpected consequences when
> multiple users are modifying the number of pages in a pool concurrently
> from the proc/sysfs interfaces.  The mutex is acquired here because we
> are modifying (decreasing) the pool size.

Yes, I got that. My question was wrt. n_mask initialization:

 +	if (nid != NUMA_NO_NODE) {
 +		init_nodemask_of_node(&nodes_allowed, nid);
 +		n_mask = &nodes_allowed;
 +	} else {
 +		n_mask = &node_states[N_MEMORY];
 +	}

AFAICS, this does not need to be protected.

with that addressed:

Reviewed-by: Oscar Salvador <osalvador@suse.de>

-- 
Oscar Salvador
SUSE Labs