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Date:   Tue, 28 Jun 2022 17:39:19 -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, duanxiongchun@bytedance.com
Subject: Re: [PATCH v2 8/8] mm: hugetlb_vmemmap: use PTRS_PER_PTE instead of
 PMD_SIZE / PAGE_SIZE
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References: <20220628092235.91270-1-songmuchun@bytedance.com>
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On 06/28/22 17:22, Muchun Song wrote:
> There is already a macro PTRS_PER_PTE to represent the number of page table
> entries, just use it.
> 
> Signed-off-by: Muchun Song <songmuchun@bytedance.com>
> ---
>  mm/hugetlb_vmemmap.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/mm/hugetlb_vmemmap.c b/mm/hugetlb_vmemmap.c
> index 6bbc445b1a66..65b527e1799c 100644
> --- a/mm/hugetlb_vmemmap.c
> +++ b/mm/hugetlb_vmemmap.c
> @@ -48,7 +48,7 @@ static int __split_vmemmap_huge_pmd(pmd_t *pmd, unsigned long start)
>  
>  	pmd_populate_kernel(&init_mm, &__pmd, pgtable);
>  
> -	for (i = 0; i < PMD_SIZE / PAGE_SIZE; i++, addr += PAGE_SIZE) {
> +	for (i = 0; i < PTRS_PER_PTE; i++, addr += PAGE_SIZE) {
>  		pte_t entry, *pte;
>  		pgprot_t pgprot = PAGE_KERNEL;
>  
> -- 
> 2.11.0
> 

That certainly seems like right macro/value to use.

Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>

-- 
Mike Kravetz