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Date:   Thu, 1 Sep 2022 11:03:07 +0200
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Subject: Re: [PATCH] mm: hugetlb: eliminate memory-less nodes handling
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To:     Aneesh Kumar K V <aneesh.kumar@linux.ibm.com>,
        Muchun Song <songmuchun@bytedance.com>,
        gregkh@linuxfoundation.org, rafael@kernel.org,
        mike.kravetz@oracle.com, akpm@linux-foundation.org,
        osalvador@suse.de, ying.huang@intel.com, rientjes@google.com
Cc:     linux-kernel@vger.kernel.org, linux-mm@kvack.org
References: <20220901083023.42319-1-songmuchun@bytedance.com>
 <c39c6ed2-4766-71d2-d459-6bb39f09943a@linux.ibm.com>
From:   David Hildenbrand <david@redhat.com>
Organization: Red Hat
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On 01.09.22 11:00, Aneesh Kumar K V wrote:
> On 9/1/22 2:00 PM, Muchun Song wrote:
>> The memory-notify-based approach aims to handle meory-less nodes, however, it just adds
>> the complexity of code as pointed by David in thread [1].  The handling of memory-less
>> nodes is introduced by commit 4faf8d950ec4 ("hugetlb: handle memory hot-plug events").
>> From its commit message, we cannot find any necessity of handling this case. So, we can
>> simply register/unregister sysfs entries in register_node/unregister_node to simlify the
>> code.
> 
> Isn't that hotplug callback added because in hugetlb_register_all_nodes() we register
> sysfs nodes only for N_MEMORY nodes? 
> 

Right, that needs adjustment as well.


-- 
Thanks,

David / dhildenb