This function always returns 1, thus no need to check return value in hugetlb_cow(). By doing so, we can get rid of the unnecessary WARN_ON call. While this logic perhaps existed as a way of identifying future unmap_ref_private() mishandling, reality is it serves no apparent purpose.
Signed-off-by: Davidlohr Bueso <[email protected]> --- mm/hugetlb.c | 32 ++++++++++++++------------------ 1 file changed, 14 insertions(+), 18 deletions(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 2024bbd..3c4d535 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -2753,8 +2753,8 @@ void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, * from other VMAs and let the children be SIGKILLed if they are faulting the * same region. */ -static int unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma, - struct page *page, unsigned long address) +static void unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma, + struct page *page, unsigned long address) { struct hstate *h = hstate_vma(vma); struct vm_area_struct *iter_vma; @@ -2793,8 +2793,6 @@ static int unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma, address + huge_page_size(h), page); } mutex_unlock(&mapping->i_mmap_mutex); - - return 1; } /* @@ -2856,20 +2854,18 @@ retry_avoidcopy: */ if (outside_reserve) { BUG_ON(huge_pte_none(pte)); - if (unmap_ref_private(mm, vma, old_page, address)) { - BUG_ON(huge_pte_none(pte)); - spin_lock(ptl); - ptep = huge_pte_offset(mm, address & huge_page_mask(h)); - if (likely(ptep && - pte_same(huge_ptep_get(ptep), pte))) - goto retry_avoidcopy; - /* - * race occurs while re-acquiring page table - * lock, and our job is done. - */ - return 0; - } - WARN_ON_ONCE(1); + unmap_ref_private(mm, vma, old_page, address); + BUG_ON(huge_pte_none(pte)); + spin_lock(ptl); + ptep = huge_pte_offset(mm, address & huge_page_mask(h)); + if (likely(ptep && + pte_same(huge_ptep_get(ptep), pte))) + goto retry_avoidcopy; + /* + * race occurs while re-acquiring page table + * lock, and our job is done. + */ + return 0; } /* Caller expects lock to be held */ -- 1.8.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
