Re: [PATCH] mm: fix account pmd page to the process

[zhong jiang]

On 2016/6/16 19:22, zhongjiang wrote:
> From: zhong jiang <zhongjiang@xxxxxxxxxx>
>
> when a process acquire a pmd table shared by other process, we
> increase the account to current process. otherwise, a race result
> in other tasks have set the pud entry. so it no need to increase it.
>
> Signed-off-by: zhong jiang <zhongjiang@xxxxxxxxxx>
> ---
>  mm/hugetlb.c | 5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)
>
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index 19d0d08..3b025c5 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -4189,10 +4189,9 @@ pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud)
>  	if (pud_none(*pud)) {
>  		pud_populate(mm, pud,
>  				(pmd_t *)((unsigned long)spte & PAGE_MASK));
> -	} else {
> +	} else 
>  		put_page(virt_to_page(spte));
> -		mm_inc_nr_pmds(mm);
> -	}
> +
>  	spin_unlock(ptl);
>  out:
>  	pte = (pte_t *)pmd_alloc(mm, pud, addr);