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

[Eric Dumazet <eric.dumazet@gmail.com>]

Le mercredi 15 décembre 2010 à 19:18 +0100, Eric Dumazet a écrit :
> 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);
>  
>  	if (gnet_stats_copy_queue(d, &qs) < 0)
>  		return -1;
> 


By the way, I could not find out how to make "tc -s class show dev ifb0"
reports correct backlog information on parent class itself :

Here we can see 126p, and 0b in backlog :

class cbq 1:11 parent 1:1 leaf 11: rate 50000Kbit cell 8b mpu 64b (bounded) prio 2/2 weight 50000Kbit allot 2250b 
level 0 ewma 5 avpkt 1500b maxidle 0us 
 Sent 330418440 bytes 226314 pkt (dropped 280142, overlimits 689534 requeues 0) 
 rate 52200Kbit 4469pps backlog 0b 126p requeues 0 
  borrowed 0 overactions 182814 avgidle -3363 undertime 2812

qdisc is OK :

qdisc sfq 11: parent 1:11 limit 127p quantum 1514b flows 127/1024 perturb 60sec 
 Sent 1712372746 bytes 1172859 pkt (dropped 1451945, overlimits 0 requeues 0) 
 rate 52287Kbit 4477pps backlog 185420b 127p requeues 0