pkt_sched: Fix tx queue selection in tc_modify_qdisc
After the recent mq change there is the new select_queue qdisc class
method used in tc_modify_qdisc, but it works OK only for direct child
qdiscs of mq qdisc. Grandchildren always get the first tx queue, which
would give wrong qdisc_root etc. results (e.g. for sch_htb as child of
sch_prio). This patch fixes it by using parent's dev_queue for such
grandchildren qdiscs. The select_queue method's return type is changed
BTW.
With feedback from: Patrick McHardy <kaber@trash.net>
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/sch_mq.c b/net/sched/sch_mq.c
index dd5ee02..600c501 100644
--- a/net/sched/sch_mq.c
+++ b/net/sched/sch_mq.c
@@ -125,13 +125,18 @@
return netdev_get_tx_queue(dev, ntx);
}
-static unsigned int mq_select_queue(struct Qdisc *sch, struct tcmsg *tcm)
+static struct netdev_queue *mq_select_queue(struct Qdisc *sch,
+ struct tcmsg *tcm)
{
unsigned int ntx = TC_H_MIN(tcm->tcm_parent);
+ struct netdev_queue *dev_queue = mq_queue_get(sch, ntx);
- if (!mq_queue_get(sch, ntx))
- return 0;
- return ntx - 1;
+ if (!dev_queue) {
+ struct net_device *dev = qdisc_dev(sch);
+
+ return netdev_get_tx_queue(dev, 0);
+ }
+ return dev_queue;
}
static int mq_graft(struct Qdisc *sch, unsigned long cl, struct Qdisc *new,