net_sched: sch_htb: export class backlog in dumps

We already get child qdisc qlen, we also can get its backlog
so that class dumps can report it.

Also replace qstats by a single drop counter, but move it in
a separate cache line so that drops do not dirty useful cache lines.

Tested:

$ tc -s cl sh dev eth0
class htb 1:1 root leaf 3: prio 0 rate 1Gbit ceil 1Gbit burst 500000b cburst 500000b
 Sent 2183346912 bytes 9021815 pkt (dropped 2340774, overlimits 0 requeues 0)
 rate 1001Mbit 517543pps backlog 120758b 499p requeues 0
 lended: 9021770 borrowed: 0 giants: 0
 tokens: 9 ctokens: 9

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2016-06-21 23:16:51 -07:00 committed by David S. Miller
parent 008830bc32
commit 338ed9b4de

View File

@ -117,7 +117,6 @@ struct htb_class {
* Written often fields
*/
struct gnet_stats_basic_packed bstats;
struct gnet_stats_queue qstats;
struct tc_htb_xstats xstats; /* our special stats */
/* token bucket parameters */
@ -140,6 +139,8 @@ struct htb_class {
enum htb_cmode cmode; /* current mode of the class */
struct rb_node pq_node; /* node for event queue */
struct rb_node node[TC_HTB_NUMPRIO]; /* node for self or feed tree */
unsigned int drops ____cacheline_aligned_in_smp;
};
struct htb_level {
@ -595,7 +596,7 @@ static int htb_enqueue(struct sk_buff *skb, struct Qdisc *sch,
to_free)) != NET_XMIT_SUCCESS) {
if (net_xmit_drop_count(ret)) {
qdisc_qstats_drop(sch);
cl->qstats.drops++;
cl->drops++;
}
return ret;
} else {
@ -1110,17 +1111,22 @@ static int
htb_dump_class_stats(struct Qdisc *sch, unsigned long arg, struct gnet_dump *d)
{
struct htb_class *cl = (struct htb_class *)arg;
struct gnet_stats_queue qs = {
.drops = cl->drops,
};
__u32 qlen = 0;
if (!cl->level && cl->un.leaf.q)
if (!cl->level && cl->un.leaf.q) {
qlen = cl->un.leaf.q->q.qlen;
qs.backlog = cl->un.leaf.q->qstats.backlog;
}
cl->xstats.tokens = PSCHED_NS2TICKS(cl->tokens);
cl->xstats.ctokens = PSCHED_NS2TICKS(cl->ctokens);
if (gnet_stats_copy_basic(qdisc_root_sleeping_running(sch),
d, NULL, &cl->bstats) < 0 ||
gnet_stats_copy_rate_est(d, NULL, &cl->rate_est) < 0 ||
gnet_stats_copy_queue(d, NULL, &cl->qstats, qlen) < 0)
gnet_stats_copy_queue(d, NULL, &qs, qlen) < 0)
return -1;
return gnet_stats_copy_app(d, &cl->xstats, sizeof(cl->xstats));