[RFC PATCH 5/6] x86/mm: change the condition of identifying hugetlb vm

Wenwei Tao
2015-06-10T06:33:59Z

Hugetlb VMAs are not mergeable, that means a VMA couldn't have VM_HUGETLB and
VM_MERGEABLE been set in the same time. So we use VM_HUGETLB to indicate new
mergeable VMAs. Because of that a VMA which has VM_HUGETLB been set is a hugetlb
VMA only if it doesn't have VM_MERGEABLE been set in the same time.

Signed-off-by: Wenwei Tao <wenweitaowenwei@gmail.com>
---
arch/x86/mm/tlb.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c
index 3250f23..0247916 100644
--- a/arch/x86/mm/tlb.c
+++ b/arch/x86/mm/tlb.c
@@ -195,7 +195,8 @@ void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start,
goto out;
}

- if ((end != TLB_FLUSH_ALL) && !(vmflag & VM_HUGETLB))
+ if ((end != TLB_FLUSH_ALL) &&
+ !((vmflag & (VM_HUGETLB | VM_MERGEABLE)) == VM_HUGETLB))
base_pages_to_flush = (end - start) >> PAGE_SHIFT;

if (base_pages_to_flush > tlb_single_page_flush_ceiling) {
--
1.7.9.5