net_sched: add a tracepoint for qdisc creation

With this tracepoint, we could know when qdisc's are created,
especially those default qdisc's.

Sample output:

  tc-736   [001] ...1    56.230107: qdisc_create: dev=ens3 kind=pfifo parent=1:0
  tc-736   [001] ...1    56.230113: qdisc_create: dev=ens3 kind=hfsc parent=ffff:ffff
  tc-738   [001] ...1    56.256816: qdisc_create: dev=ens3 kind=pfifo parent=1:100
  tc-739   [001] ...1    56.267584: qdisc_create: dev=ens3 kind=pfifo parent=1:200
  tc-740   [001] ...1    56.279649: qdisc_create: dev=ens3 kind=fq_codel parent=1:100
  tc-741   [001] ...1    56.289996: qdisc_create: dev=ens3 kind=pfifo_fast parent=1:200
  tc-745   [000] .N.1   111.687483: qdisc_create: dev=ens3 kind=ingress parent=ffff:fff1

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Cong Wang 2020-05-26 21:35:25 -07:00 committed by David S. Miller
parent a34dac0b90
commit f5a7833e83
3 changed files with 29 additions and 1 deletions

View File

@ -96,6 +96,29 @@ TRACE_EVENT(qdisc_destroy,
TC_H_MAJ(__entry->handle) >> 16, TC_H_MIN(__entry->handle))
);
TRACE_EVENT(qdisc_create,
TP_PROTO(const struct Qdisc_ops *ops, struct net_device *dev, u32 parent),
TP_ARGS(ops, dev, parent),
TP_STRUCT__entry(
__string( dev, dev->name )
__string( kind, ops->id )
__field( u32, parent )
),
TP_fast_assign(
__assign_str(dev, dev->name);
__assign_str(kind, ops->id);
__entry->parent = parent;
),
TP_printk("dev=%s kind=%s parent=%x:%x",
__get_str(dev), __get_str(kind),
TC_H_MAJ(__entry->parent) >> 16, TC_H_MIN(__entry->parent))
);
#endif /* _TRACE_QDISC_H */
/* This part must be outside protection */

View File

@ -32,6 +32,8 @@
#include <net/pkt_sched.h>
#include <net/pkt_cls.h>
#include <trace/events/qdisc.h>
/*
Short review.
@ -1283,6 +1285,7 @@ static struct Qdisc *qdisc_create(struct net_device *dev,
}
qdisc_hash_add(sch, false);
trace_qdisc_create(ops, dev, parent);
return sch;

View File

@ -896,8 +896,10 @@ struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue,
}
sch->parent = parentid;
if (!ops->init || ops->init(sch, NULL, extack) == 0)
if (!ops->init || ops->init(sch, NULL, extack) == 0) {
trace_qdisc_create(ops, dev_queue->dev, parentid);
return sch;
}
qdisc_put(sch);
return NULL;