mm,hugetlb: make unmap_ref_private() return void
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 <davidlohr@hp.com>
Cc: Aswin Chandramouleeswaran <aswin@hp.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 7a0a73d..b94752a 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -2754,8 +2754,8 @@
* 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;
@@ -2794,8 +2794,6 @@
address + huge_page_size(h), page);
}
mutex_unlock(&mapping->i_mmap_mutex);
-
- return 1;
}
/*
@@ -2857,20 +2855,18 @@
*/
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 */