static int prio_tune(struct Qdisc *sch, struct nlattr *opt)
{
struct prio_sched_data *q = qdisc_priv(sch);
+ struct Qdisc *queues[TCQ_PRIO_BANDS];
+ int oldbands = q->bands, i;
struct tc_prio_qopt *qopt;
- int i;
if (nla_len(opt) < sizeof(*qopt))
return -EINVAL;
return -EINVAL;
}
+ /* Before commit, make sure we can allocate all new qdiscs */
+ for (i = oldbands; i < qopt->bands; i++) {
+ queues[i] = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops,
+ TC_H_MAKE(sch->handle, i + 1));
+ if (!queues[i]) {
+ while (i > oldbands)
+ qdisc_destroy(queues[--i]);
+ return -ENOMEM;
+ }
+ }
+
sch_tree_lock(sch);
q->bands = qopt->bands;
memcpy(q->prio2band, qopt->priomap, TC_PRIO_MAX+1);
- for (i = q->bands; i < TCQ_PRIO_BANDS; i++) {
+ for (i = q->bands; i < oldbands; i++) {
struct Qdisc *child = q->queues[i];
- q->queues[i] = &noop_qdisc;
- if (child != &noop_qdisc) {
- qdisc_tree_reduce_backlog(child, child->q.qlen, child->qstats.backlog);
- qdisc_destroy(child);
- }
- }
- sch_tree_unlock(sch);
- for (i = 0; i < q->bands; i++) {
- struct Qdisc *child;
+ qdisc_tree_reduce_backlog(child, child->q.qlen,
+ child->qstats.backlog);
+ qdisc_destroy(child);
+ }
- if (q->queues[i] != &noop_qdisc)
- continue;
+ for (i = oldbands; i < q->bands; i++)
+ q->queues[i] = queues[i];
- child = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops,
- TC_H_MAKE(sch->handle, i + 1));
- if (!child)
- return -ENOMEM;
- sch_tree_lock(sch);
- q->queues[i] = child;
- sch_tree_unlock(sch);
- }
+ sch_tree_unlock(sch);
return 0;
}
static int prio_init(struct Qdisc *sch, struct nlattr *opt)
{
- struct prio_sched_data *q = qdisc_priv(sch);
- int i;
-
- for (i = 0; i < TCQ_PRIO_BANDS; i++)
- q->queues[i] = &noop_qdisc;
-
- if (opt == NULL) {
+ if (!opt)
return -EINVAL;
- } else {
- int err;
- if ((err = prio_tune(sch, opt)) != 0)
- return err;
- }
- return 0;
+ return prio_tune(sch, opt);
}
static int prio_dump(struct Qdisc *sch, struct sk_buff *skb)