[v2 PATCH 2/2] mm: thp: inc counter for collapsed shmem THP

[Yang Shi <yang.shi@linux.alibaba.com>]

/sys/kernel/mm/transparent_hugepage/khugepaged/pages_collapsed is used
to record the counter of collapsed THP, but it just gets inc'ed in
anonymous THP collapse path, do this for shmem THP collapse too.

Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
---
v1 --> v2:
* Seperate from the previous patch per Kirill's comment

 mm/khugepaged.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index 9b0ec30..4018826 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -1521,6 +1521,8 @@ static void collapse_shmem(struct mm_struct *mm,
 		unlock_page(new_page);
 
 		*hpage = NULL;
+
+		khugepaged_pages_collapsed++;
 	} else {
 		/* Something went wrong: rollback changes to the radix-tree */
 		shmem_uncharge(mapping->host, nr_none);
-- 
1.8.3.1