rxrpc: Trace/count transmission underflows and cwnd resets
Add a tracepoint to log when a cwnd reset occurs due to lack of
transmission on a call.
Add stat counters to count transmission underflows (ie. when we have tx
window space, but sendmsg doesn't manage to keep up), cwnd resets and
transmission failures.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
diff --git a/net/rxrpc/call_event.c b/net/rxrpc/call_event.c
index 18591f9..9f1e490 100644
--- a/net/rxrpc/call_event.c
+++ b/net/rxrpc/call_event.c
@@ -317,8 +317,10 @@ static void rxrpc_transmit_some_data(struct rxrpc_call *call)
case RXRPC_CALL_CLIENT_AWAIT_REPLY:
if (!rxrpc_tx_window_has_space(call))
return;
- if (list_empty(&call->tx_sendmsg))
+ if (list_empty(&call->tx_sendmsg)) {
+ rxrpc_inc_stat(call->rxnet, stat_tx_data_underflow);
return;
+ }
rxrpc_decant_prepared_tx(call);
break;
default:
