Disk stat improvements

Add an option to disable the disk stats. And only dump the disk
stat header, if we actually have stats to show.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/diskutil.c b/diskutil.c
index 11d676fc..bbaa22d5 100644
--- a/diskutil.c
+++ b/diskutil.c
@@ -313,6 +313,9 @@ void show_disk_util(void)
 	struct disk_util *du;
 	double util;
 
+	if (list_empty(&disk_list))
+		return;
+
 	log_info("\nDisk stats (read/write):\n");
 
 	list_for_each(entry, &disk_list) {