zram: count same page write as page_stored

Regardless of whether it is same page or not, it's surely write and
stored to zram so we should increase pages_stored stat.  Otherwise, user
can see zero value via mm_stats although he writes a lot of pages to
zram.

Link: http://lkml.kernel.org/r/1494834068-27004-1-git-send-email-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 558e245..d3e3af2 100644 (file)
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -469,6 +469,7 @@ static bool zram_same_page_write(struct zram *zram, u32 index,
                zram_slot_unlock(zram, index);
 
                atomic64_inc(&zram->stats.same_pages);
+               atomic64_inc(&zram->stats.pages_stored);
                return true;
        }
        kunmap_atomic(mem);
@@ -524,6 +525,7 @@ static void zram_free_page(struct zram *zram, size_t index)
                zram_clear_flag(zram, index, ZRAM_SAME);
                zram_set_element(zram, index, 0);
                atomic64_dec(&zram->stats.same_pages);
+               atomic64_dec(&zram->stats.pages_stored);
                return;
        }