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Message-ID: <5763E694.1050502@huawei.com>
Date: Fri, 17 Jun 2016 20:01:24 +0800
From: zhong jiang <zhongjiang@huawei.com>
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To: Michal Hocko <mhocko@kernel.org>, Mike Kravetz <mike.kravetz@oracle.com>,
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CC: Linux Memory Management List <linux-mm@kvack.org>,
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Subject: Re: [PATCH] mm: fix account pmd page to the process
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On 2016/6/17 19:45, zhongjiang wrote:
> From: zhong jiang <zhongjiang@huawei.com>
>
> hen 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@huawei.com>
> ---
>  mm/hugetlb.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index 19d0d08..3072857 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -4191,7 +4191,7 @@ pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud)
>  				(pmd_t *)((unsigned long)spte & PAGE_MASK));
>  	} else {
>  		put_page(virt_to_page(spte));
> -		mm_inc_nr_pmds(mm);
> +		mm_dec_nr_pmds(mm);
>  	}
>  	spin_unlock(ptl);
>  out: