SUNRPC: Trace a few more generic svc_xprt events

In lieu of dprintks or tracepoints in each individual transport
implementation, introduce tracepoints in the generic part of the RPC
layer. These typically fire for connection lifetime events, so
shouldn't contribute a lot of noise.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

include/trace/events/rpcrdma.h

@@ -1279,38 +1279,6 @@ TRACE_EVENT(xprtrdma_leaked_rep,
  ** Server-side RPC/RDMA events
  **/
 
-DECLARE_EVENT_CLASS(svcrdma_xprt_event,
-	TP_PROTO(
-		const struct svc_xprt *xprt
-	),
-
-	TP_ARGS(xprt),
-
-	TP_STRUCT__entry(
-		__field(const void *, xprt)
-		__string(addr, xprt->xpt_remotebuf)
-	),
-
-	TP_fast_assign(
-		__entry->xprt = xprt;
-		__assign_str(addr, xprt->xpt_remotebuf);
-	),
-
-	TP_printk("xprt=%p addr=%s",
-		__entry->xprt, __get_str(addr)
-	)
-);
-
-#define DEFINE_XPRT_EVENT(name)						\
-		DEFINE_EVENT(svcrdma_xprt_event, svcrdma_xprt_##name,	\
-				TP_PROTO(				\
-					const struct svc_xprt *xprt	\
-				),					\
-				TP_ARGS(xprt))
-
-DEFINE_XPRT_EVENT(accept);
-DEFINE_XPRT_EVENT(free);
-
 DECLARE_EVENT_CLASS(svcrdma_accept_class,
 	TP_PROTO(
 		const struct svcxprt_rdma *rdma,

include/trace/events/sunrpc.h

@@ -1236,9 +1236,42 @@ DECLARE_EVENT_CLASS(svc_xprt_event,
 		show_svc_xprt_flags(__entry->flags))
 );
 
-DEFINE_EVENT(svc_xprt_event, svc_xprt_no_write_space,
-	TP_PROTO(struct svc_xprt *xprt),
-	TP_ARGS(xprt));
+#define DEFINE_SVC_XPRT_EVENT(name) \
+	DEFINE_EVENT(svc_xprt_event, svc_xprt_##name, \
+			TP_PROTO( \
+				struct svc_xprt *xprt \
+			), \
+			TP_ARGS(xprt))
+
+DEFINE_SVC_XPRT_EVENT(no_write_space);
+DEFINE_SVC_XPRT_EVENT(close);
+DEFINE_SVC_XPRT_EVENT(detach);
+DEFINE_SVC_XPRT_EVENT(free);
+
+TRACE_EVENT(svc_xprt_accept,
+	TP_PROTO(
+		const struct svc_xprt *xprt,
+		const char *service
+	),
+
+	TP_ARGS(xprt, service),
+
+	TP_STRUCT__entry(
+		__string(addr, xprt->xpt_remotebuf)
+		__string(protocol, xprt->xpt_class->xcl_name)
+		__string(service, service)
+	),
+
+	TP_fast_assign(
+		__assign_str(addr, xprt->xpt_remotebuf);
+		__assign_str(protocol, xprt->xpt_class->xcl_name)
+		__assign_str(service, service);
+	),
+
+	TP_printk("addr=%s protocol=%s service=%s",
+		__get_str(addr), __get_str(protocol), __get_str(service)
+	)
+);
 
 TRACE_EVENT(svc_xprt_dequeue,
 	TP_PROTO(struct svc_rqst *rqst),

net/sunrpc/svc_xprt.c

@@ -153,6 +153,7 @@ static void svc_xprt_free(struct kref *kref)
 		xprt_put(xprt->xpt_bc_xprt);
 	if (xprt->xpt_bc_xps)
 		xprt_switch_put(xprt->xpt_bc_xps);
+	trace_svc_xprt_free(xprt);
 	xprt->xpt_ops->xpo_free(xprt);
 	module_put(owner);
 }
@@ -309,15 +310,11 @@ int svc_create_xprt(struct svc_serv *serv, const char *xprt_name,
 {
 	int err;
 
-	dprintk("svc: creating transport %s[%d]\n", xprt_name, port);
 	err = _svc_create_xprt(serv, xprt_name, net, family, port, flags, cred);
 	if (err == -EPROTONOSUPPORT) {
 		request_module("svc%s", xprt_name);
 		err = _svc_create_xprt(serv, xprt_name, net, family, port, flags, cred);
 	}
-	if (err < 0)
-		dprintk("svc: transport %s not found, err %d\n",
-			xprt_name, -err);
 	return err;
 }
 EXPORT_SYMBOL_GPL(svc_create_xprt);
@@ -785,7 +782,6 @@ static int svc_handle_xprt(struct svc_rqst *rqstp, struct svc_xprt *xprt)
 	int len = 0;
 
 	if (test_bit(XPT_CLOSE, &xprt->xpt_flags)) {
-		dprintk("svc_recv: found XPT_CLOSE\n");
 		if (test_and_clear_bit(XPT_KILL_TEMP, &xprt->xpt_flags))
 			xprt->xpt_ops->xpo_kill_temp_xprt(xprt);
 		svc_delete_xprt(xprt);
@@ -804,6 +800,7 @@ static int svc_handle_xprt(struct svc_rqst *rqstp, struct svc_xprt *xprt)
 		if (newxpt) {
 			newxpt->xpt_cred = get_cred(xprt->xpt_cred);
 			svc_add_new_temp_xprt(serv, newxpt);
+			trace_svc_xprt_accept(newxpt, serv->sv_name);
 		} else
 			module_put(xprt->xpt_class->xcl_owner);
 	} else if (svc_xprt_reserve_slot(rqstp, xprt)) {
@@ -840,14 +837,6 @@ int svc_recv(struct svc_rqst *rqstp, long timeout)
 	struct svc_serv		*serv = rqstp->rq_server;
 	int			len, err;
 
-	dprintk("svc: server %p waiting for data (to = %ld)\n",
-		rqstp, timeout);
-
-	if (rqstp->rq_xprt)
-		printk(KERN_ERR
-			"svc_recv: service %p, transport not NULL!\n",
-			 rqstp);
-
 	err = svc_alloc_arg(rqstp);
 	if (err)
 		goto out;
@@ -895,7 +884,6 @@ EXPORT_SYMBOL_GPL(svc_recv);
 void svc_drop(struct svc_rqst *rqstp)
 {
 	trace_svc_drop(rqstp);
-	dprintk("svc: xprt %p dropped request\n", rqstp->rq_xprt);
 	svc_xprt_release(rqstp);
 }
 EXPORT_SYMBOL_GPL(svc_drop);
@@ -1030,11 +1018,10 @@ static void svc_delete_xprt(struct svc_xprt *xprt)
 	struct svc_serv	*serv = xprt->xpt_server;
 	struct svc_deferred_req *dr;
 
-	/* Only do this once */
 	if (test_and_set_bit(XPT_DEAD, &xprt->xpt_flags))
-		BUG();
+		return;
 
-	dprintk("svc: svc_delete_xprt(%p)\n", xprt);
+	trace_svc_xprt_detach(xprt);
 	xprt->xpt_ops->xpo_detach(xprt);
 	if (xprt->xpt_bc_xprt)
 		xprt->xpt_bc_xprt->ops->close(xprt->xpt_bc_xprt);
@@ -1055,6 +1042,7 @@ static void svc_delete_xprt(struct svc_xprt *xprt)
 
 void svc_close_xprt(struct svc_xprt *xprt)
 {
+	trace_svc_xprt_close(xprt);
 	set_bit(XPT_CLOSE, &xprt->xpt_flags);
 	if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags))
 		/* someone else will have to effect the close */

net/sunrpc/svcsock.c

@@ -727,7 +727,6 @@ static struct svc_xprt *svc_tcp_accept(struct svc_xprt *xprt)
 	int		err, slen;
 	RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
 
-	dprintk("svc: tcp_accept %p sock %p\n", svsk, sock);
 	if (!sock)
 		return NULL;
 
@@ -1363,11 +1362,6 @@ static struct svc_xprt *svc_create_socket(struct svc_serv *serv,
 	int		newlen;
 	int		family;
 	int		val;
-	RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
-
-	dprintk("svc: svc_create_socket(%s, %d, %s)\n",
-			serv->sv_program->pg_name, protocol,
-			__svc_print_addr(sin, buf, sizeof(buf)));
 
 	if (protocol != IPPROTO_UDP && protocol != IPPROTO_TCP) {
 		printk(KERN_WARNING "svc: only UDP and TCP "
@@ -1427,7 +1421,6 @@ static struct svc_xprt *svc_create_socket(struct svc_serv *serv,
 	svc_xprt_set_local(&svsk->sk_xprt, newsin, newlen);
 	return (struct svc_xprt *)svsk;
 bummer:
-	dprintk("svc: svc_create_socket error = %d\n", -error);
 	sock_release(sock);
 	return ERR_PTR(error);
 }
@@ -1441,8 +1434,6 @@ static void svc_sock_detach(struct svc_xprt *xprt)
 	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
 	struct sock *sk = svsk->sk_sk;
 
-	dprintk("svc: svc_sock_detach(%p)\n", svsk);
-
 	/* put back the old socket callbacks */
 	lock_sock(sk);
 	sk->sk_state_change = svsk->sk_ostate;
@@ -1459,8 +1450,6 @@ static void svc_tcp_sock_detach(struct svc_xprt *xprt)
 {
 	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
 
-	dprintk("svc: svc_tcp_sock_detach(%p)\n", svsk);
-
 	svc_sock_detach(xprt);
 
 	if (!test_bit(XPT_LISTENER, &xprt->xpt_flags)) {
@@ -1475,7 +1464,6 @@ static void svc_tcp_sock_detach(struct svc_xprt *xprt)
 static void svc_sock_free(struct svc_xprt *xprt)
 {
 	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
-	dprintk("svc: svc_sock_free(%p)\n", svsk);
 
 	if (svsk->sk_sock->file)
 		sockfd_put(svsk->sk_sock);

net/sunrpc/xprtrdma/svc_rdma_transport.c

@@ -314,11 +314,8 @@ static struct svc_xprt *svc_rdma_create(struct svc_serv *serv,
 	struct svcxprt_rdma *cma_xprt;
 	int ret;
 
-	dprintk("svcrdma: Creating RDMA listener\n");
-	if ((sa->sa_family != AF_INET) && (sa->sa_family != AF_INET6)) {
-		dprintk("svcrdma: Address family %d is not supported.\n", sa->sa_family);
+	if (sa->sa_family != AF_INET && sa->sa_family != AF_INET6)
 		return ERR_PTR(-EAFNOSUPPORT);
-	}
 	cma_xprt = svc_rdma_create_xprt(serv, net);
 	if (!cma_xprt)
 		return ERR_PTR(-ENOMEM);
@@ -329,7 +326,6 @@ static struct svc_xprt *svc_rdma_create(struct svc_serv *serv,
 				   RDMA_PS_TCP, IB_QPT_RC);
 	if (IS_ERR(listen_id)) {
 		ret = PTR_ERR(listen_id);
-		dprintk("svcrdma: rdma_create_id failed = %d\n", ret);
 		goto err0;
 	}
 
@@ -338,23 +334,17 @@ static struct svc_xprt *svc_rdma_create(struct svc_serv *serv,
 	 */
 #if IS_ENABLED(CONFIG_IPV6)
 	ret = rdma_set_afonly(listen_id, 1);
-	if (ret) {
-		dprintk("svcrdma: rdma_set_afonly failed = %d\n", ret);
+	if (ret)
 		goto err1;
-	}
 #endif
 	ret = rdma_bind_addr(listen_id, sa);
-	if (ret) {
-		dprintk("svcrdma: rdma_bind_addr failed = %d\n", ret);
+	if (ret)
 		goto err1;
-	}
 	cma_xprt->sc_cm_id = listen_id;
 
 	ret = rdma_listen(listen_id, RPCRDMA_LISTEN_BACKLOG);
-	if (ret) {
-		dprintk("svcrdma: rdma_listen failed = %d\n", ret);
+	if (ret)
 		goto err1;
-	}
 
 	/*
 	 * We need to use the address from the cm_id in case the
@@ -537,7 +527,6 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt)
 	dprintk("    ord             : %d\n", conn_param.initiator_depth);
 #endif
 
-	trace_svcrdma_xprt_accept(&newxprt->sc_xprt);
 	return &newxprt->sc_xprt;
 
  errout:
@@ -578,8 +567,6 @@ static void __svc_rdma_free(struct work_struct *work)
 		container_of(work, struct svcxprt_rdma, sc_work);
 	struct svc_xprt *xprt = &rdma->sc_xprt;
 
-	trace_svcrdma_xprt_free(xprt);
-
 	if (rdma->sc_qp && !IS_ERR(rdma->sc_qp))
 		ib_drain_qp(rdma->sc_qp);