[PATCH net-next 3/4] rxrpc: Trace ack.rwind

David Howells
2023-02-08T10:29:42Z

Log ack.rwind in the rxrpc_tx_ack tracepoint. This value is useful to see
as it represents flow-control information to the peer.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
---
include/trace/events/rxrpc.h | 11 +++++++----
net/rxrpc/conn_event.c | 2 +-
net/rxrpc/output.c | 10 +++++++---
3 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/include/trace/events/rxrpc.h b/include/trace/events/rxrpc.h
index d7bb4acf4580..c3c0b0aa8381 100644
--- a/include/trace/events/rxrpc.h
+++ b/include/trace/events/rxrpc.h
@@ -1118,9 +1118,9 @@ TRACE_EVENT(rxrpc_tx_data,
TRACE_EVENT(rxrpc_tx_ack,
TP_PROTO(unsigned int call, rxrpc_serial_t serial,
rxrpc_seq_t ack_first, rxrpc_serial_t ack_serial,
- u8 reason, u8 n_acks),
+ u8 reason, u8 n_acks, u16 rwind),

- TP_ARGS(call, serial, ack_first, ack_serial, reason, n_acks),
+ TP_ARGS(call, serial, ack_first, ack_serial, reason, n_acks, rwind),

TP_STRUCT__entry(
__field(unsigned int, call)
@@ -1129,6 +1129,7 @@ TRACE_EVENT(rxrpc_tx_ack,
__field(rxrpc_serial_t, ack_serial)
__field(u8, reason)
__field(u8, n_acks)
+ __field(u16, rwind)
),

TP_fast_assign(
@@ -1138,15 +1139,17 @@ TRACE_EVENT(rxrpc_tx_ack,
__entry->ack_serial = ack_serial;
__entry->reason = reason;
__entry->n_acks = n_acks;
+ __entry->rwind = rwind;
),

- TP_printk(" c=%08x ACK %08x %s f=%08x r=%08x n=%u",
+ TP_printk(" c=%08x ACK %08x %s f=%08x r=%08x n=%u rw=%u",
__entry->call,
__entry->serial,
__print_symbolic(__entry->reason, rxrpc_ack_names),
__entry->ack_first,
__entry->ack_serial,
- __entry->n_acks)
+ __entry->n_acks,
+ __entry->rwind)
);

TRACE_EVENT(rxrpc_receive,
diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c
index 44414e724415..95f4bc206b3d 100644
--- a/net/rxrpc/conn_event.c
+++ b/net/rxrpc/conn_event.c
@@ -163,7 +163,7 @@ void rxrpc_conn_retransmit_call(struct rxrpc_connection *conn,
trace_rxrpc_tx_ack(chan->call_debug_id, serial,
ntohl(pkt.ack.firstPacket),
ntohl(pkt.ack.serial),
- pkt.ack.reason, 0);
+ pkt.ack.reason, 0, rxrpc_rx_window_size);
break;

default:
diff --git a/net/rxrpc/output.c b/net/rxrpc/output.c
index 6b2022240076..5e53429c6922 100644
--- a/net/rxrpc/output.c
+++ b/net/rxrpc/output.c
@@ -80,7 +80,8 @@ static void rxrpc_set_keepalive(struct rxrpc_call *call)
*/
static size_t rxrpc_fill_out_ack(struct rxrpc_connection *conn,
struct rxrpc_call *call,
- struct rxrpc_txbuf *txb)
+ struct rxrpc_txbuf *txb,
+ u16 *_rwind)
{
struct rxrpc_ackinfo ackinfo;
unsigned int qsize, sack, wrap, to;
@@ -124,6 +125,7 @@ static size_t rxrpc_fill_out_ack(struct rxrpc_connection *conn,
jmax = rxrpc_rx_jumbo_max;
qsize = (window - 1) - call->rx_consumed;
rsize = max_t(int, call->rx_winsize - qsize, 0);
+ *_rwind = rsize;
ackinfo.rxMTU = htonl(rxrpc_rx_mtu);
ackinfo.maxMTU = htonl(mtu);
ackinfo.rwind = htonl(rsize);
@@ -190,6 +192,7 @@ int rxrpc_send_ack_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb)
rxrpc_serial_t serial;
size_t len, n;
int ret, rtt_slot = -1;
+ u16 rwind;

if (test_bit(RXRPC_CALL_DISCONNECTED, &call->flags))
return -ECONNRESET;
@@ -205,7 +208,7 @@ int rxrpc_send_ack_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb)
if (txb->ack.reason == RXRPC_ACK_PING)
txb->wire.flags |= RXRPC_REQUEST_ACK;

- n = rxrpc_fill_out_ack(conn, call, txb);
+ n = rxrpc_fill_out_ack(conn, call, txb, &rwind);
if (n == 0)
return 0;

@@ -217,7 +220,8 @@ int rxrpc_send_ack_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb)
txb->wire.serial = htonl(serial);
trace_rxrpc_tx_ack(call->debug_id, serial,
ntohl(txb->ack.firstPacket),
- ntohl(txb->ack.serial), txb->ack.reason, txb->ack.nAcks);
+ ntohl(txb->ack.serial), txb->ack.reason, txb->ack.nAcks,
+ rwind);

if (txb->ack.reason == RXRPC_ACK_PING)
rtt_slot = rxrpc_begin_rtt_probe(call, serial, rxrpc_rtt_tx_ping);