Commit 09dbdf28 authored by Vladimir Oltean's avatar Vladimir Oltean Committed by Paolo Abeni
Browse files

net/sched: taprio: fix calculation of maximum gate durations 

taprio_calculate_gate_durations() depends on netdev_get_num_tc() and
this returns 0. So it calculates the maximum gate durations for no
traffic class.

I had tested the blamed commit only with another patch in my tree, one
which in the end I decided isn't valuable enough to submit ("net/sched:
taprio: mask off bits in gate mask that exceed number of TCs").

The problem is that having this patch threw off my testing. By moving
the netdev_set_num_tc() call earlier, we implicitly gave to
taprio_calculate_gate_durations() the information it needed.

Extract only the portion from the unsubmitted change which applies the
mqprio configuration to the netdev earlier.

Link: https://patchwork.kernel.org/project/netdevbpf/patch/20230130173145.475943-15-vladimir.oltean@nxp.com/


Fixes: a306a90c ("net/sched: taprio: calculate tc gate durations")
Signed-off-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: default avatarKurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parent c0783818

net/sched/sch_taprio.c

+17 −17
Original line number Diff line number Diff line
@@ -1833,23 +1833,6 @@ static int taprio_change(struct Qdisc *sch, struct nlattr *opt, 
		goto free_sched;

	}



	err = parse_taprio_schedule(q, tb, new_admin, extack);

	if (err < 0)

		goto free_sched;



	if (new_admin->num_entries == 0) {

		NL_SET_ERR_MSG(extack, "There should be at least one entry in the schedule");

		err = -EINVAL;

		goto free_sched;

	}



	err = taprio_parse_clockid(sch, tb, extack);

	if (err < 0)

		goto free_sched;



	taprio_set_picos_per_byte(dev, q);

	taprio_update_queue_max_sdu(q, new_admin, stab);



	if (mqprio) {

		err = netdev_set_num_tc(dev, mqprio->num_tc);

		if (err)
@@ -1867,6 +1850,23 @@ static int taprio_change(struct Qdisc *sch, struct nlattr *opt, 
					       mqprio->prio_tc_map[i]);

	}



	err = parse_taprio_schedule(q, tb, new_admin, extack);

	if (err < 0)

		goto free_sched;



	if (new_admin->num_entries == 0) {

		NL_SET_ERR_MSG(extack, "There should be at least one entry in the schedule");

		err = -EINVAL;

		goto free_sched;

	}



	err = taprio_parse_clockid(sch, tb, extack);

	if (err < 0)

		goto free_sched;



	taprio_set_picos_per_byte(dev, q);

	taprio_update_queue_max_sdu(q, new_admin, stab);



	if (FULL_OFFLOAD_IS_ENABLED(q->flags))

		err = taprio_enable_offload(dev, q, new_admin, extack);

	else