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/[email protected]/
Fixes: a306a90c8ffe ("net/sched: taprio: calculate tc gate durations")
Signed-off-by: Vladimir Oltean <[email protected]>
---
net/sched/sch_taprio.c | 34 +++++++++++++++++-----------------
1 file changed, 17 insertions(+), 17 deletions(-)
diff --git a/net/sched/sch_taprio.c b/net/sched/sch_taprio.c
index 9781b47962bb..556e72ec0f38 100644
--- a/net/sched/sch_taprio.c
+++ b/net/sched/sch_taprio.c
@@ -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
--
2.34.1
On Thu Feb 16 2023, Vladimir Oltean wrote:
> 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/[email protected]/
> Fixes: a306a90c8ffe ("net/sched: taprio: calculate tc gate durations")
> Signed-off-by: Vladimir Oltean <[email protected]>
Reviewed-by: Kurt Kanzenbach <[email protected]>