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Subject: Re: [PATCH 5/8] hugetlb: rename vma_shareable() and refactor code
To:     Mike Kravetz <mike.kravetz@oracle.com>
CC:     Muchun Song <songmuchun@bytedance.com>,
        David Hildenbrand <david@redhat.com>,
        Michal Hocko <mhocko@suse.com>, Peter Xu <peterx@redhat.com>,
        Naoya Horiguchi <naoya.horiguchi@linux.dev>,
        "Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com>,
        Andrea Arcangeli <aarcange@redhat.com>,
        "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
        Davidlohr Bueso <dave@stgolabs.net>,
        Prakash Sangappa <prakash.sangappa@oracle.com>,
        James Houghton <jthoughton@google.com>,
        Mina Almasry <almasrymina@google.com>,
        Pasha Tatashin <pasha.tatashin@soleen.com>,
        Axel Rasmussen <axelrasmussen@google.com>,
        Ray Fucillo <Ray.Fucillo@intersystems.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Linux-MM <linux-mm@kvack.org>,
        linux-kernel <linux-kernel@vger.kernel.org>
References: <20220824175757.20590-1-mike.kravetz@oracle.com>
 <20220824175757.20590-6-mike.kravetz@oracle.com>
From:   Miaohe Lin <linmiaohe@huawei.com>
Message-ID: <98db8106-77cf-291d-9642-e429b8b33160@huawei.com>
Date:   Sat, 27 Aug 2022 16:07:31 +0800
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On 2022/8/25 1:57, Mike Kravetz wrote:
> Rename the routine vma_shareable to vma_addr_pmd_shareable as it is
> checking a specific address within the vma.  Refactor code to check if
> an aligned range is shareable as this will be needed in a subsequent
> patch.
> 
> Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>

LGTM. Thanks.

Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>

Thanks,
Miaohe Lin

> ---
>  mm/hugetlb.c | 19 +++++++++++++------
>  1 file changed, 13 insertions(+), 6 deletions(-)
> 
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index a6eb46c64baf..758b6844d566 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -6648,26 +6648,33 @@ static unsigned long page_table_shareable(struct vm_area_struct *svma,
>  	return saddr;
>  }
>  
> -static bool vma_shareable(struct vm_area_struct *vma, unsigned long addr)
> +static bool __vma_aligned_range_pmd_shareable(struct vm_area_struct *vma,
> +				unsigned long start, unsigned long end)
>  {
> -	unsigned long base = addr & PUD_MASK;
> -	unsigned long end = base + PUD_SIZE;
> -
>  	/*
>  	 * check on proper vm_flags and page table alignment
>  	 */
> -	if (vma->vm_flags & VM_MAYSHARE && range_in_vma(vma, base, end))
> +	if (vma->vm_flags & VM_MAYSHARE && range_in_vma(vma, start, end))
>  		return true;
>  	return false;
>  }
>  
> +static bool vma_addr_pmd_shareable(struct vm_area_struct *vma,
> +						unsigned long addr)
> +{
> +	unsigned long start = addr & PUD_MASK;
> +	unsigned long end = start + PUD_SIZE;
> +
> +	return __vma_aligned_range_pmd_shareable(vma, start, end);
> +}
> +
>  bool want_pmd_share(struct vm_area_struct *vma, unsigned long addr)
>  {
>  #ifdef CONFIG_USERFAULTFD
>  	if (uffd_disable_huge_pmd_share(vma))
>  		return false;
>  #endif
> -	return vma_shareable(vma, addr);
> +	return vma_addr_pmd_shareable(vma, addr);
>  }
>  
>  /*
>