blktrace fixup + documentation

Add a little documentation on using blktrace data files.

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

1 files changed, 3 insertions, 0 deletions

diff --git a/blktrace.c b/blktrace.c
index 864e9dc7..1669fe55 100644
--- a/blktrace.c
+++ b/blktrace.c
@@ -100,6 +100,7 @@ static void handle_trace(struct thread_data *td, struct blk_io_trace *t,
 
 	rw = (t->action & BLK_TC_ACT(BLK_TC_WRITE)) != 0;
 	ios[rw]++;
+	td->o.size += t->bytes;
 	store_ipo(td, t->sector, t->bytes, rw, ttime);
 }
 
@@ -120,6 +121,8 @@ int load_blktrace(struct thread_data *td, const char *filename)
 		return 1;
 	}
 
+	td->o.size = 0;
+
 	ios[0] = ios[1] = 0;
 	ttime = 0;
 	do {