On 2/9/21 11:54 PM, Miaohe Lin wrote:
> If there is no reservation corresponding to a vma, map_chg is always != 0,
> i.e. we can not meet the condition where a vma does not have reservation
> while map_chg = 0.
This commit message might be easier to understand?
vma_resv_map(vma) checks if a reserve map is associated with the vma. The
routine vma_needs_reservation() will check vma_resv_map(vma) and return 1
if no reserv map is present. map_chg is set to the return value of
vma_needs_reservation(). Therefore, !vma_resv_map(vma) is redundant in the
expression:
map_chg || avoid_reserve || !vma_resv_map(vma);
Remove the redundant check.
--
Mike Kravetz
>
> Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
> ---
> mm/hugetlb.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index 4f2c92ddbca4..36c3646fa55f 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -2311,7 +2311,7 @@ struct page *alloc_huge_page(struct vm_area_struct *vma,
>
> /* If this allocation is not consuming a reservation, charge it now.
> */
> - deferred_reserve = map_chg || avoid_reserve || !vma_resv_map(vma);
> + deferred_reserve = map_chg || avoid_reserve;
> if (deferred_reserve) {
> ret = hugetlb_cgroup_charge_cgroup_rsvd(
> idx, pages_per_huge_page(h), &h_cg);
>
