On Tue, 2016-08-23 at 13:24 -0700, John Fastabend wrote:
> Enable dflt qdisc support for per cpu stats before this patch a
> dflt qdisc was required to use the global statistics qstats and
> bstats.
>
> Signed-off-by: John Fastabend <[email protected]>
> ---
> net/sched/sch_generic.c | 24 ++++++++++++++++++++----
> 1 file changed, 20 insertions(+), 4 deletions(-)
>
> diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
> index 80544c2..910b4d15 100644
> --- a/net/sched/sch_generic.c
> +++ b/net/sched/sch_generic.c
> @@ -646,18 +646,34 @@ struct Qdisc *qdisc_create_dflt(struct netdev_queue
> *dev_queue,
> struct Qdisc *sch;
>
> if (!try_module_get(ops->owner))
> - goto errout;
> + return NULL;
>
> sch = qdisc_alloc(dev_queue, ops);
> if (IS_ERR(sch))
> - goto errout;
> + return NULL;
> sch->parent = parentid;
>
> - if (!ops->init || ops->init(sch, NULL) == 0)
> + if (!ops->init)
> return sch;
>
> - qdisc_destroy(sch);
> + if (ops->init(sch, NULL))
> + goto errout;
> +
> + /* init() may have set percpu flags so init data structures */
> + if (qdisc_is_percpu_stats(sch)) {
> + sch->cpu_bstats =
> + netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu);
> + if (!sch->cpu_bstats)
> + goto errout;
> +
> + sch->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
> + if (!sch->cpu_qstats)
> + goto errout;
> + }
> +
> + return sch;
> errout:
> + qdisc_destroy(sch);
> return NULL;
> }
> EXPORT_SYMBOL(qdisc_create_dflt);
>
Hmm... apparently we have bug here, added in
6da7c8fcbcbdb50ec ("qdisc: allow setting default queuing discipline")
We do not undo the try_module_get() in case of an error.
I will send a fix.
