f2fs: show extent tree, node stat info in debugfs

This patch add and show stat info of total memory footprint for extent tree,node
in debugfs.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/debug.c b/fs/f2fs/debug.c
index e671373..1006290 100644
--- a/fs/f2fs/debug.c
+++ b/fs/f2fs/debug.c
@@ -35,6 +35,8 @@
 	/* validation check of the segment numbers */
 	si->hit_ext = sbi->read_hit_ext;
 	si->total_ext = sbi->total_hit_ext;
+	si->ext_tree = sbi->total_ext_tree;
+	si->ext_node = atomic_read(&sbi->total_ext_node);
 	si->ndirty_node = get_pages(sbi, F2FS_DIRTY_NODES);
 	si->ndirty_dent = get_pages(sbi, F2FS_DIRTY_DENTS);
 	si->ndirty_dirs = sbi->n_dirty_dirs;
@@ -185,6 +187,9 @@
 	si->cache_mem += sbi->n_dirty_dirs * sizeof(struct inode_entry);
 	for (i = 0; i <= UPDATE_INO; i++)
 		si->cache_mem += sbi->im[i].ino_num * sizeof(struct ino_entry);
+	si->cache_mem += sbi->total_ext_tree * sizeof(struct extent_tree);
+	si->cache_mem += atomic_read(&sbi->total_ext_node) *
+						sizeof(struct extent_node);
 
 	si->page_mem = 0;
 	npages = NODE_MAPPING(sbi)->nrpages;
@@ -267,6 +272,8 @@
 		seq_printf(s, "  - node blocks : %d\n", si->node_blks);
 		seq_printf(s, "\nExtent Hit Ratio: %d / %d\n",
 			   si->hit_ext, si->total_ext);
+		seq_printf(s, "\nExtent Tree Count: %d\n", si->ext_tree);
+		seq_printf(s, "\nExtent Node Count: %d\n", si->ext_node);
 		seq_puts(s, "\nBalancing F2FS Async:\n");
 		seq_printf(s, "  - inmem: %4d, wb: %4d\n",
 			   si->inmem_pages, si->wb_pages);