Re: [PATCH net-next-2.6] net_sched: sch_sfq: add backlog info in sfq_dump_class_stats()

Jarek Poplawski
2010-12-16T08:16:27Z

On 2010-12-15 19:18, Eric Dumazet wrote:
> We currently return for each active SFQ slot the number of packets in
> queue. We can also give number of bytes accounted for these packets.
>
> tc -s class show dev ifb0
>
> Before patch :
>
> class sfq 11:3d9 parent 11:
> (dropped 0, overlimits 0 requeues 0)
> backlog 0b 3p requeues 0
> allot 1266
>
> After patch :
>
> class sfq 11:3e4 parent 11:
> (dropped 0, overlimits 0 requeues 0)
> backlog 4380b 3p requeues 0
> allot 1212
>
>
> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
> ---
> net/sched/sch_sfq.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/net/sched/sch_sfq.c b/net/sched/sch_sfq.c
> index 3cf478d..cb331de 100644
> --- a/net/sched/sch_sfq.c
> +++ b/net/sched/sch_sfq.c
> @@ -548,8 +548,13 @@ static int sfq_dump_class_stats(struct Qdisc *sch, unsigned long cl,
> {
> struct sfq_sched_data *q = qdisc_priv(sch);
> sfq_index idx = q->ht[cl-1];
> - struct gnet_stats_queue qs = { .qlen = q->qs[idx].qlen };
> + struct sk_buff_head *list = &q->qs[idx];
> + struct gnet_stats_queue qs = { .qlen = list->qlen };
> struct tc_sfq_xstats xstats = { .allot = q->allot[idx] };
> + struct sk_buff *skb;
> +
> + skb_queue_walk(list, skb)
> + qs.backlog += qdisc_pkt_len(skb);

I don't think you can walk this list without the qdisc lock.

Jarek P.