net_sched: Add accessor function for packet length for qdiscs

Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/sch_dsmark.c b/net/sched/sch_dsmark.c
index 44d347e..a935676 100644
--- a/net/sched/sch_dsmark.c
+++ b/net/sched/sch_dsmark.c
@@ -258,7 +258,7 @@
 		return err;
 	}
 
-	sch->bstats.bytes += skb->len;
+	sch->bstats.bytes += qdisc_pkt_len(skb);
 	sch->bstats.packets++;
 	sch->q.qlen++;