From 70713dddf3d25a02d1952f8c5d2688c986d2f2fb Mon Sep 17 00:00:00 2001 From: Qitao Xu Date: Wed, 14 Jul 2021 23:03:24 -0700 Subject: net_sched: introduce tracepoint trace_qdisc_enqueue() Tracepoint trace_qdisc_enqueue() is introduced to trace skb at the entrance of TC layer on TX side. This is similar to trace_qdisc_dequeue(): 1. For both we only trace successful cases. The failure cases can be traced via trace_kfree_skb(). 2. They are called at entrance or exit of TC layer, not for each ->enqueue() or ->dequeue(). This is intentional, because we want to make trace_qdisc_enqueue() symmetric to trace_qdisc_dequeue(), which is easier to use. The return value of qdisc_enqueue() is not interesting here, we have Qdisc's drop packets in ->dequeue(), it is impossible to trace them even if we have the return value, the only way to trace them is tracing kfree_skb(). We only add information we need to trace ring buffer. If any other information is needed, it is easy to extend it without breaking ABI, see commit 3dd344ea84e1 ("net: tracepoint: exposing sk_family in all tcp:tracepoints"). Reviewed-by: Cong Wang Signed-off-by: Qitao Xu Signed-off-by: David S. Miller --- include/trace/events/qdisc.h | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) (limited to 'include/trace') diff --git a/include/trace/events/qdisc.h b/include/trace/events/qdisc.h index 58209557cb3a..c3006c6b4a87 100644 --- a/include/trace/events/qdisc.h +++ b/include/trace/events/qdisc.h @@ -46,6 +46,32 @@ TRACE_EVENT(qdisc_dequeue, __entry->txq_state, __entry->packets, __entry->skbaddr ) ); +TRACE_EVENT(qdisc_enqueue, + + TP_PROTO(struct Qdisc *qdisc, const struct netdev_queue *txq, struct sk_buff *skb), + + TP_ARGS(qdisc, txq, skb), + + TP_STRUCT__entry( + __field(struct Qdisc *, qdisc) + __field(void *, skbaddr) + __field(int, ifindex) + __field(u32, handle) + __field(u32, parent) + ), + + TP_fast_assign( + __entry->qdisc = qdisc; + __entry->skbaddr = skb; + __entry->ifindex = txq->dev ? txq->dev->ifindex : 0; + __entry->handle = qdisc->handle; + __entry->parent = qdisc->parent; + ), + + TP_printk("enqueue ifindex=%d qdisc handle=0x%X parent=0x%X skbaddr=%px", + __entry->ifindex, __entry->handle, __entry->parent, __entry->skbaddr) +); + TRACE_EVENT(qdisc_reset, TP_PROTO(struct Qdisc *q), -- cgit v1.2.3