From c6672e3fe4a641bf302d6309ab4d5ee55648e758 Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 23 Sep 2016 13:58:55 +0100 Subject: [PATCH] rxrpc: Add a tracepoint to log which packets will be retransmitted Add a tracepoint to log in rxrpc_resend() which packets will be retransmitted. Note that if a positive ACK comes in whilst we have dropped the lock to retransmit another packet, the actual retransmission may not happen, though some of the effects will (such as altering the congestion management). Signed-off-by: David Howells --- include/trace/events/rxrpc.h | 27 +++++++++++++++++++++++++++ net/rxrpc/call_event.c | 2 ++ 2 files changed, 29 insertions(+) diff --git a/include/trace/events/rxrpc.h b/include/trace/events/rxrpc.h index d67a8c6b085a..56475497043d 100644 --- a/include/trace/events/rxrpc.h +++ b/include/trace/events/rxrpc.h @@ -543,6 +543,33 @@ TRACE_EVENT(rxrpc_propose_ack, rxrpc_propose_ack_outcomes[__entry->outcome]) ); +TRACE_EVENT(rxrpc_retransmit, + TP_PROTO(struct rxrpc_call *call, rxrpc_seq_t seq, u8 annotation, + s64 expiry), + + TP_ARGS(call, seq, annotation, expiry), + + TP_STRUCT__entry( + __field(struct rxrpc_call *, call ) + __field(rxrpc_seq_t, seq ) + __field(u8, annotation ) + __field(s64, expiry ) + ), + + TP_fast_assign( + __entry->call = call; + __entry->seq = seq; + __entry->annotation = annotation; + __entry->expiry = expiry; + ), + + TP_printk("c=%p q=%x a=%02x xp=%lld", + __entry->call, + __entry->seq, + __entry->annotation, + __entry->expiry) + ); + #endif /* _TRACE_RXRPC_H */ /* This part must be outside protection */ diff --git a/net/rxrpc/call_event.c b/net/rxrpc/call_event.c index fd5b11339ffb..a78a92fe5d77 100644 --- a/net/rxrpc/call_event.c +++ b/net/rxrpc/call_event.c @@ -196,6 +196,8 @@ static void rxrpc_resend(struct rxrpc_call *call) /* Okay, we need to retransmit a packet. */ call->rxtx_annotations[ix] = RXRPC_TX_ANNO_RETRANS | annotation; + trace_rxrpc_retransmit(call, seq, annotation | anno_type, + ktime_to_ns(ktime_sub(skb->tstamp, max_age))); } resend_at = ktime_sub(ktime_add_ms(oldest, rxrpc_resend_timeout), now); -- 2.20.1