Re: [PATCH 5/8] hugetlb: rename vma_shareable() and refactor code

From: Miaohe Lin
Date: Sat Aug 27 2022 - 04:07:48 EST


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@xxxxxxxxxx>

LGTM. Thanks.

Reviewed-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>

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);
> }
>
> /*
>