rpcrdma: Trace connection registration and unregistration

These new trace points record xarray indices and the time of
endpoint registration and unregistration, to co-ordinate with
device removal events.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

include/trace/events/rpcrdma.h

@@ -2277,6 +2277,42 @@ DEFINE_CLIENT_DEVICE_EVENT(rpcrdma_client_remove_one);
 DEFINE_CLIENT_DEVICE_EVENT(rpcrdma_client_wait_on);
 DEFINE_CLIENT_DEVICE_EVENT(rpcrdma_client_remove_one_done);
 
+DECLARE_EVENT_CLASS(rpcrdma_client_register_class,
+	TP_PROTO(
+		const struct ib_device *device,
+		const struct rpcrdma_notification *rn
+	),
+
+	TP_ARGS(device, rn),
+
+	TP_STRUCT__entry(
+		__string(name, device->name)
+		__field(void *, callback)
+		__field(u32, index)
+	),
+
+	TP_fast_assign(
+		__assign_str(name);
+		__entry->callback = rn->rn_done;
+		__entry->index = rn->rn_index;
+	),
+
+	TP_printk("device=%s index=%u done callback=%pS\n",
+		__get_str(name), __entry->index, __entry->callback
+	)
+);
+
+#define DEFINE_CLIENT_REGISTER_EVENT(name)				\
+	DEFINE_EVENT(rpcrdma_client_register_class, name,		\
+	TP_PROTO(							\
+		const struct ib_device *device,				\
+		const struct rpcrdma_notification *rn			\
+	),								\
+	TP_ARGS(device, rn))
+
+DEFINE_CLIENT_REGISTER_EVENT(rpcrdma_client_register);
+DEFINE_CLIENT_REGISTER_EVENT(rpcrdma_client_unregister);
+
 #endif /* _TRACE_RPCRDMA_H */
 
 #include <trace/define_trace.h>

net/sunrpc/xprtrdma/ib_client.c

@@ -66,6 +66,7 @@ int rpcrdma_rn_register(struct ib_device *device,
 		return -ENOMEM;
 	kref_get(&rd->rd_kref);
 	rn->rn_done = done;
+	trace_rpcrdma_client_register(device, rn);
 	return 0;
 }
 
@@ -91,6 +92,7 @@ void rpcrdma_rn_unregister(struct ib_device *device,
 	if (!rd)
 		return;
 
+	trace_rpcrdma_client_unregister(device, rn);
 	xa_erase(&rd->rd_xa, rn->rn_index);
 	kref_put(&rd->rd_kref, rpcrdma_rn_release);
 }