rxrpc: Add tracepoint for working out where aborts happen

Add a tracepoint for working out where local aborts happen.  Each
tracepoint call is labelled with a 3-letter code so that they can be
distinguished - and the DATA sequence number is added too where available.

rxrpc_kernel_abort_call() also takes a 3-letter code so that AFS can
indicate the circumstances when it aborts a call.

Signed-off-by: David Howells <dhowells@redhat.com>
diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c
index 9db90f4..8c7938b 100644
--- a/net/rxrpc/conn_event.c
+++ b/net/rxrpc/conn_event.c
@@ -158,6 +158,11 @@
 			lockdep_is_held(&conn->channel_lock));
 		if (call) {
 			rxrpc_see_call(call);
+			if (compl == RXRPC_CALL_LOCALLY_ABORTED)
+				trace_rxrpc_abort("CON", call->cid,
+						  call->call_id, 0,
+						  abort_code, error);
+
 			write_lock_bh(&call->state_lock);
 			if (rxrpc_set_call_completion(call, compl, abort_code,
 						      error)) {
@@ -167,6 +172,7 @@
 			write_unlock_bh(&call->state_lock);
 			if (queue)
 				rxrpc_queue_call(call);
+
 		}
 	}