f2fs: push some variables to debug part

Some, counters are needed only for the statistical information
while debugging.
So, those can be controlled using CONFIG_F2FS_STAT_FS,
pushing the usage for few variables under this flag.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 1644fff..93917e3 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -68,7 +68,9 @@
 					struct buffer_head *bh_result)
 {
 	struct f2fs_inode_info *fi = F2FS_I(inode);
+#ifdef CONFIG_F2FS_STAT_FS
 	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
+#endif
 	pgoff_t start_fofs, end_fofs;
 	block_t start_blkaddr;
 
@@ -78,7 +80,9 @@
 		return 0;
 	}
 
+#ifdef CONFIG_F2FS_STAT_FS
 	sbi->total_hit_ext++;
+#endif
 	start_fofs = fi->ext.fofs;
 	end_fofs = fi->ext.fofs + fi->ext.len - 1;
 	start_blkaddr = fi->ext.blk_addr;
@@ -96,7 +100,9 @@
 		else
 			bh_result->b_size = UINT_MAX;
 
+#ifdef CONFIG_F2FS_STAT_FS
 		sbi->read_hit_ext++;
+#endif
 		read_unlock(&fi->ext.ext_lock);
 		return 1;
 	}