[PATCH 3/3 -mmotm-2009-12-10-17-19] Fix wrong rss counting of smap

[Minchan Kim <minchan.kim@gmail.com>]

After return zero_page, vm_normal_page can return
NULL if the page is zero page.

In such case, RSS and PSS can be mismatched.
This patch fixes it.

Signed-off-by: Minchan Kim <minchan.kim@gmail.com>
---
 fs/proc/task_mmu.c |    5 ++---
 1 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 47c03f4..1a47be9 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -361,12 +361,11 @@ static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 		if (!pte_present(ptent))
 			continue;
 
-		mss->resident += PAGE_SIZE;
-
 		page = vm_normal_page(vma, addr, ptent);
-		if (!page)
+		if (!page && !is_zero_pfn(pte_pfn(ptent)))
 			continue;
 
+		mss->resident += PAGE_SIZE;
 		/* Accumulate the size in pages that have been accessed. */
 		if (pte_young(ptent) || PageReferenced(page))
 			mss->referenced += PAGE_SIZE;
-- 
1.5.6.5

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>