thp: fix anon memory statistics with transparent hugepages

Count each transparent hugepage as HPAGE_PMD_NR pages in the LRU
statistics, so the Active(anon) and Inactive(anon) statistics in
/proc/meminfo are correct.

Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 8 insertions, 0 deletions

diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
index 827595228734..9b48c24df260 100644
--- a/include/linux/huge_mm.h
+++ b/include/linux/huge_mm.h
@@ -117,11 +117,19 @@ static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
                 return;
         __vma_adjust_trans_huge(vma, start, end, adjust_next);
 }
+static inline int hpage_nr_pages(struct page *page)
+{
+        if (unlikely(PageTransHuge(page)))
+                return HPAGE_PMD_NR;
+        return 1;
+}
 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
 #define HPAGE_PMD_SHIFT ({ BUG(); 0; })
 #define HPAGE_PMD_MASK ({ BUG(); 0; })
 #define HPAGE_PMD_SIZE ({ BUG(); 0; })
 
+#define hpage_nr_pages(x) 1
+
 #define transparent_hugepage_enabled(__vma) 0
 
 #define transparent_hugepage_flags 0UL