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Date:   Mon, 13 Jun 2022 14:19:45 -0700
From:   Mike Kravetz <mike.kravetz@oracle.com>
To:     Muchun Song <songmuchun@bytedance.com>
Cc:     david@redhat.com, akpm@linux-foundation.org, corbet@lwn.net,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        linux-doc@vger.kernel.org
Subject: Re: [PATCH 3/6] mm: hugetlb_vmemmap: introduce the name HVO
Message-ID: <Yqep8QwtfcRCCPsI@monkey>
References: <20220613063512.17540-1-songmuchun@bytedance.com>
 <20220613063512.17540-4-songmuchun@bytedance.com>
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On Mon, Jun 13, 2022 at 02:35:09PM +0800”, Muchun Song wrote:
> It it inconvenient to mention the feature of optimizing vmemmap pages associated
> with HugeTLB pages when communicating with others since there is no specific or
> abbreviated name for it when it is first introduced.  Let us give it a name HVO
> (HugeTLB Vmemmap Optimization) from now.
> 
> This commit also updates the document about "hugetlb_free_vmemmap" by the way
> discussed in thread [1].
> 
> Link: https://lore.kernel.org/all/21aae898-d54d-cc4b-a11f-1bb7fddcfffa@redhat.com/ [1]
> Signed-off-by: Muchun Song <songmuchun@bytedance.com>
> ---

> diff --git a/Documentation/admin-guide/mm/hugetlbpage.rst b/Documentation/admin-guide/mm/hugetlbpage.rst
> index a90330d0a837..64e0d5c512e7 100644
> --- a/Documentation/admin-guide/mm/hugetlbpage.rst
> +++ b/Documentation/admin-guide/mm/hugetlbpage.rst
> @@ -164,8 +164,7 @@ default_hugepagesz
>  	will all result in 256 2M huge pages being allocated.  Valid default
>  	huge page size is architecture dependent.
>  hugetlb_free_vmemmap
> -	When CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP is set, this enables optimizing
> -	unused vmemmap pages associated with each HugeTLB page.
> +	When CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP is set, this enables HVO.

I think we need to define HVO before using it here.  Readers may be able
to determine the meaning, but to be sure I would suggest:

When CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP is set this enables
HugeTLB Vmemmap Optimization (HVO).

Everything else looks good to me.
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
-- 
Mike Kravetz