sunrpc: Save remote presentation address in svc_xprt for trace events

TP_printk defines a format string that is passed to user space for
converting raw trace event records to something human-readable.

My user space's printf (Oracle Linux 7), however, does not have a
%pI format specifier. The result is that what is supposed to be an
IP address in the output of "trace-cmd report" is just a string that
says the field couldn't be displayed.

To fix this, adopt the same approach as the client: maintain a pre-
formated presentation address for occasions when %pI is not
available.

The location of the trace_svc_send trace point is adjusted so that
rqst->rq_xprt is not NULL when the trace event is recorded.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/include/linux/sunrpc/svc_xprt.h b/include/linux/sunrpc/svc_xprt.h
index 19475acb68ea..c3d72066d4b1 100644
--- a/include/linux/sunrpc/svc_xprt.h
+++ b/include/linux/sunrpc/svc_xprt.h
@@ -83,6 +83,7 @@ struct svc_xprt {
 	size_t			xpt_locallen;	/* length of address */
 	struct sockaddr_storage	xpt_remote;	/* remote peer's address */
 	size_t			xpt_remotelen;	/* length of address */
+	char			xpt_remotebuf[INET6_ADDRSTRLEN + 10];
 	struct rpc_wait_queue	xpt_bc_pending;	/* backchannel wait queue */
 	struct list_head	xpt_users;	/* callbacks on free */
 
@@ -152,7 +153,10 @@ static inline void svc_xprt_set_remote(struct svc_xprt *xprt,
 {
 	memcpy(&xprt->xpt_remote, sa, salen);
 	xprt->xpt_remotelen = salen;
+	snprintf(xprt->xpt_remotebuf, sizeof(xprt->xpt_remotebuf) - 1,
+		 "%pISpc", sa);
 }
+
 static inline unsigned short svc_addr_port(const struct sockaddr *sa)
 {
 	const struct sockaddr_in *sin = (const struct sockaddr_in *)sa;