[PATCH] mm: fix account pmd page to the process

From: zhongjiang
Date: Thu Jun 16 2016 - 07:06:38 EST


From: zhong jiang <zhongjiang@xxxxxxxxxx>

when 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@xxxxxxxxxx>
---
mm/hugetlb.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 19d0d08..3b025c5 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -4189,10 +4189,9 @@ pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud)
if (pud_none(*pud)) {
pud_populate(mm, pud,
(pmd_t *)((unsigned long)spte & PAGE_MASK));
- } else {
+ } else
put_page(virt_to_page(spte));
- mm_inc_nr_pmds(mm);
- }
+
spin_unlock(ptl);
out:
pte = (pte_t *)pmd_alloc(mm, pud, addr);
--
1.8.3.1