From ff2998f29f390d963299103f0b247cc79106ced5 Mon Sep 17 00:00:00 2001 From: Jesper Dangaard Brouer Date: Thu, 26 Feb 2026 14:44:12 +0100 Subject: net: sched: introduce qdisc-specific drop reason tracing MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Create new enum qdisc_drop_reason and trace_qdisc_drop tracepoint for qdisc layer drop diagnostics with direct qdisc context visibility. The new tracepoint includes qdisc handle, parent, kind (name), and device information. Existing SKB_DROP_REASON_QDISC_DROP is retained for backwards compatibility via kfree_skb_reason(). Convert qdiscs with drop reasons to use the new infrastructure. Change CAKE's cobalt_should_drop() return type from enum skb_drop_reason to enum qdisc_drop_reason to fix implicit enum conversion warnings. Use QDISC_DROP_UNSPEC as the 'not dropped' sentinel instead of SKB_NOT_DROPPED_YET. Both have the same compiled value (0), so the comparison logic remains semantically equivalent. Signed-off-by: Jesper Dangaard Brouer Reviewed-by: Toke Høiland-Jørgensen Link: https://patch.msgid.link/177211345275.3011628.1974310302645218067.stgit@firesoul Signed-off-by: Jakub Kicinski --- include/trace/events/qdisc.h | 51 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) (limited to 'include/trace') diff --git a/include/trace/events/qdisc.h b/include/trace/events/qdisc.h index ff33f41a9db7..d8a5c2677470 100644 --- a/include/trace/events/qdisc.h +++ b/include/trace/events/qdisc.h @@ -74,6 +74,57 @@ TRACE_EVENT(qdisc_enqueue, __entry->ifindex, __entry->handle, __entry->parent, __entry->skbaddr) ); +#undef FN +#undef FNe +#define FN(reason) TRACE_DEFINE_ENUM(QDISC_DROP_##reason); +#define FNe(reason) TRACE_DEFINE_ENUM(QDISC_DROP_##reason); +DEFINE_QDISC_DROP_REASON(FN, FNe) + +#undef FN +#undef FNe +#define FN(reason) { QDISC_DROP_##reason, #reason }, +#define FNe(reason) { QDISC_DROP_##reason, #reason } + +TRACE_EVENT(qdisc_drop, + + TP_PROTO(struct Qdisc *qdisc, const struct netdev_queue *txq, + struct net_device *dev, struct sk_buff *skb, + enum qdisc_drop_reason reason), + + TP_ARGS(qdisc, txq, dev, skb, reason), + + 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(enum qdisc_drop_reason, reason) + __string(kind, qdisc->ops->id) + ), + + TP_fast_assign( + __entry->qdisc = qdisc; + __entry->txq = txq; + __entry->skbaddr = skb; + __entry->ifindex = dev ? dev->ifindex : 0; + __entry->handle = qdisc->handle; + __entry->parent = qdisc->parent; + __entry->reason = reason; + __assign_str(kind); + ), + + TP_printk("drop ifindex=%d kind=%s handle=0x%X parent=0x%X skbaddr=%p reason=%s", + __entry->ifindex, __get_str(kind), __entry->handle, + __entry->parent, __entry->skbaddr, + __print_symbolic(__entry->reason, + DEFINE_QDISC_DROP_REASON(FN, FNe))) +); + +#undef FN +#undef FNe + TRACE_EVENT(qdisc_reset, TP_PROTO(struct Qdisc *q), -- cgit v1.2.3