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>

2 files changed, 13 insertions, 3 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
diff --git a/include/linux/mm_inline.h b/include/linux/mm_inline.h
index 650f31eabdb1..8f7d24712dc1 100644
--- a/include/linux/mm_inline.h
+++ b/include/linux/mm_inline.h
@@ -1,6 +1,8 @@
 #ifndef LINUX_MM_INLINE_H
 #define LINUX_MM_INLINE_H
 
+#include <linux/huge_mm.h>
+
 /**
  * page_is_file_cache - should the page be on a file LRU or anon LRU?
  * @page: the page to test
@@ -24,7 +26,7 @@ __add_page_to_lru_list(struct zone *zone, struct page *page, enum lru_list l,
                        struct list_head *head)
 {
         list_add(&page->lru, head);
-        __inc_zone_state(zone, NR_LRU_BASE + l);
+        __mod_zone_page_state(zone, NR_LRU_BASE + l, hpage_nr_pages(page));
         mem_cgroup_add_lru_list(page, l);
 }
 
@@ -38,7 +40,7 @@ static inline void
 del_page_from_lru_list(struct zone *zone, struct page *page, enum lru_list l)
 {
         list_del(&page->lru);
-        __dec_zone_state(zone, NR_LRU_BASE + l);
+        __mod_zone_page_state(zone, NR_LRU_BASE + l, -hpage_nr_pages(page));
         mem_cgroup_del_lru_list(page, l);
 }
 
@@ -73,7 +75,7 @@ del_page_from_lru(struct zone *zone, struct page *page)
                         l += LRU_ACTIVE;
                 }
         }
-        __dec_zone_state(zone, NR_LRU_BASE + l);
+        __mod_zone_page_state(zone, NR_LRU_BASE + l, -hpage_nr_pages(page));
         mem_cgroup_del_lru_list(page, l);
 }