pkt_sched: Add and use qdisc_root() and qdisc_root_lock().
When code wants to lock the qdisc tree state, the logic
operation it's doing is locking the top-level qdisc that
sits of the root of the netdev_queue.
Add qdisc_root_lock() to represent this and convert the
easiest cases.
In order for this to work out in all cases, we have to
hook up the noop_qdisc to a dummy netdev_queue.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
index 830ccc5..19c244a 100644
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -633,7 +633,7 @@
if (!ops->init || (err = ops->init(sch, tca[TCA_OPTIONS])) == 0) {
if (tca[TCA_RATE]) {
err = gen_new_estimator(&sch->bstats, &sch->rate_est,
- &sch->dev_queue->lock,
+ qdisc_root_lock(sch),
tca[TCA_RATE]);
if (err) {
/*
@@ -675,7 +675,7 @@
}
if (tca[TCA_RATE])
gen_replace_estimator(&sch->bstats, &sch->rate_est,
- &sch->dev_queue->lock, tca[TCA_RATE]);
+ qdisc_root_lock(sch), tca[TCA_RATE]);
return 0;
}
@@ -967,7 +967,7 @@
q->qstats.qlen = q->q.qlen;
if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS,
- TCA_XSTATS, &q->dev_queue->lock, &d) < 0)
+ TCA_XSTATS, qdisc_root_lock(q), &d) < 0)
goto nla_put_failure;
if (q->ops->dump_stats && q->ops->dump_stats(q, &d) < 0)
@@ -1216,7 +1216,7 @@
goto nla_put_failure;
if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS,
- TCA_XSTATS, &q->dev_queue->lock, &d) < 0)
+ TCA_XSTATS, qdisc_root_lock(q), &d) < 0)
goto nla_put_failure;
if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0)