[net-next 2/2] qdisc: add tracepoint qdisc:qdisc_requeue for requeued SKBs
From: <hidden>
Date: 2021-07-11 05:00:19
Subsystem:
networking [general], tc subsystem, the rest, tracing · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Jamal Hadi Salim, Jiri Pirko, Linus Torvalds, Steven Rostedt, Masami Hiramatsu
From: Tonghao Zhang <redacted> The main purpose of this tracepoint is to monitor what, how many and why packets were requeued. The txq_state can be used for determining the reason for packets requeued. Signed-off-by: Tonghao Zhang <redacted> --- include/trace/events/qdisc.h | 32 ++++++++++++++++++++++++++++++++ net/sched/sch_generic.c | 8 +++++--- 2 files changed, 37 insertions(+), 3 deletions(-)
diff --git a/include/trace/events/qdisc.h b/include/trace/events/qdisc.h
index b0e76237bb74..c6187a8fc103 100644
--- a/include/trace/events/qdisc.h
+++ b/include/trace/events/qdisc.h@@ -78,6 +78,38 @@ TRACE_EVENT(qdisc_dequeue, __entry->txq_state, __entry->packets, __entry->skbaddr ) ); +TRACE_EVENT(qdisc_requeue, + + TP_PROTO(struct sk_buff *skb, struct Qdisc *qdisc, + const struct netdev_queue *txq), + + TP_ARGS(skb, qdisc, txq), + + TP_STRUCT__entry( + __field( struct Qdisc *, qdisc ) + __field(const struct netdev_queue *, txq ) + __field( void *, skbaddr ) + __field( int, ifindex ) + __field( u32, handle ) + __field( u32, parent ) + __field( unsigned long, txq_state) + ), + + TP_fast_assign( + __entry->qdisc = qdisc; + __entry->txq = txq; + __entry->skbaddr = skb; + __entry->ifindex = txq->dev ? txq->dev->ifindex : 0; + __entry->handle = qdisc->handle; + __entry->parent = qdisc->parent; + __entry->txq_state = txq->state; + ), + + TP_printk("requeue ifindex=%d qdisc handle=0x%X parent=0x%X txq_state=0x%lX skbaddr=%p", + __entry->ifindex, __entry->handle, __entry->parent, + __entry->txq_state, __entry->skbaddr) +); + TRACE_EVENT(qdisc_reset, TP_PROTO(struct Qdisc *q),
diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
index 75605075178f..0701d1e9d221 100644
--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c@@ -137,7 +137,8 @@ static inline void qdisc_enqueue_skb_bad_txq(struct Qdisc *q, spin_unlock(lock); } -static inline void dev_requeue_skb(struct sk_buff *skb, struct Qdisc *q) +static inline void dev_requeue_skb(struct sk_buff *skb, struct Qdisc *q, + struct netdev_queue *txq) { spinlock_t *lock = NULL;
@@ -149,6 +150,7 @@ static inline void dev_requeue_skb(struct sk_buff *skb, struct Qdisc *q) while (skb) { struct sk_buff *next = skb->next; + trace_qdisc_requeue(skb, q, txq); __skb_queue_tail(&q->gso_skb, skb); /* it's still part of the queue */
@@ -325,7 +327,7 @@ bool sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q, if (root_lock) spin_lock(root_lock); - dev_requeue_skb(skb, q); + dev_requeue_skb(skb, q, txq); return false; } #endif
@@ -353,7 +355,7 @@ bool sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q, net_warn_ratelimited("BUG %s code %d qlen %d\n", dev->name, ret, q->q.qlen); - dev_requeue_skb(skb, q); + dev_requeue_skb(skb, q, txq); return false; }
--
2.27.0