Re: [PATCH v3 8/9] mm, hugetlb: remove decrement_hugepage_resv_vma()

Hillf Danton
2013-07-29T09:39:08Z

On Mon, Jul 29, 2013 at 1:28 PM, Joonsoo Kim <iamjoonsoo.kim@lge.com> wrote:
> Now, Checking condition of decrement_hugepage_resv_vma() and
> vma_has_reserves() is same, so we can clean-up this function with
> vma_has_reserves(). Additionally, decrement_hugepage_resv_vma() has only
> one call site, so we can remove function and embed it into
> dequeue_huge_page_vma() directly. This patch implement it.
>
> Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
>
Acked-by: Hillf Danton <dhillf@gmail.com>

> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index ca15854..4b1b043 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -434,25 +434,6 @@ static int is_vma_resv_set(struct vm_area_struct *vma, unsigned long flag)
> return (get_vma_private_data(vma) & flag) != 0;
> }
>
> -/* Decrement the reserved pages in the hugepage pool by one */
> -static void decrement_hugepage_resv_vma(struct hstate *h,
> - struct vm_area_struct *vma)
> -{
> - if (vma->vm_flags & VM_NORESERVE)
> - return;
> -
> - if (vma->vm_flags & VM_MAYSHARE) {
> - /* Shared mappings always use reserves */
> - h->resv_huge_pages--;
> - } else if (is_vma_resv_set(vma, HPAGE_RESV_OWNER)) {
> - /*
> - * Only the process that called mmap() has reserves for
> - * private mappings.
> - */
> - h->resv_huge_pages--;
> - }
> -}
> -
> /* Reset counters to 0 and clear all HPAGE_RESV_* flags */
> void reset_vma_resv_huge_pages(struct vm_area_struct *vma)
> {
> @@ -466,10 +447,18 @@ static int vma_has_reserves(struct vm_area_struct *vma)
> {
> if (vma->vm_flags & VM_NORESERVE)
> return 0;
> +
> + /* Shared mappings always use reserves */
> if (vma->vm_flags & VM_MAYSHARE)
> return 1;
> +
> + /*
> + * Only the process that called mmap() has reserves for
> + * private mappings.
> + */
> if (is_vma_resv_set(vma, HPAGE_RESV_OWNER))
> return 1;
> +
> return 0;
> }
>
> @@ -564,8 +553,8 @@ retry_cpuset:
> if (cpuset_zone_allowed_softwall(zone, htlb_alloc_mask)) {
> page = dequeue_huge_page_node(h, zone_to_nid(zone));
> if (page) {
> - if (!avoid_reserve)
> - decrement_hugepage_resv_vma(h, vma);
> + if (!avoid_reserve && vma_has_reserves(vma))
> + h->resv_huge_pages--;
> break;
> }
> }
> --
> 1.7.9.5
>