Re: [net-next 1/2] qdisc: add tracepoint qdisc:qdisc_enqueue for enqueued SKBs

On Sat, Jul 10, 2021 at 10:00 PM [off-list ref] wrote:

From: Tonghao Zhang <redacted>

This tracepoint can work with qdisc:qdisc_dequeue to measure
packets latency in qdisc queue. In some case, for example,
if TX queues are stopped or frozen, sch_direct_xmit will invoke
the dev_requeue_skb to requeue SKBs to qdisc->gso_skb, that may
delay the SKBs in qdisc queue.

With this patch, we can measure packets latency.

Coincidentally, we have a nearly same patch:
https://marc.info/?l=linux-netdev&m=162580785123913&w=2

Also, '%p' certainly does not work, it produces same address for
different packets. This is why we changed it to '%px', see:
https://marc.info/?l=linux-netdev&m=162580784823909&w=2

Thanks.