f2fs: increase pages_skipped when skipping writepages

This patch increases pages_skipped when skipping writepages.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index cb514f1..7cc146b 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -1209,7 +1209,7 @@
 
 	/* collect a number of dirty node pages and write together */
 	if (get_pages(sbi, F2FS_DIRTY_NODES) < nr_pages_to_skip(sbi, NODE))
-		return 0;
+		goto skip_write;
 
 	/* if mounting is failed, skip writing node pages */
 	wbc->nr_to_write = 3 * max_hw_blocks(sbi);
@@ -1218,6 +1218,10 @@
 	wbc->nr_to_write = nr_to_write - (3 * max_hw_blocks(sbi) -
 						wbc->nr_to_write);
 	return 0;
+
+skip_write:
+	wbc->pages_skipped += get_pages(sbi, F2FS_DIRTY_NODES);
+	return 0;
 }
 
 static int f2fs_set_node_page_dirty(struct page *page)