SUNRPC: Fix tracepoint storage issues with svc_recv and svc_rqst_status

There is no guarantee that either the request or the svc_xprt exist
by the time we get round to printing the trace message.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

include/trace/events/sunrpc.h

@@ -455,20 +455,22 @@ TRACE_EVENT(svc_recv,
 	TP_ARGS(rqst, status),
 
 	TP_STRUCT__entry(
-		__field(struct sockaddr *, addr)
 		__field(__be32, xid)
 		__field(int, status)
 		__field(unsigned long, flags)
+		__dynamic_array(unsigned char, addr, rqst->rq_addrlen)
 	),
 
 	TP_fast_assign(
-		__entry->addr = (struct sockaddr *)&rqst->rq_addr;
 		__entry->xid = status > 0 ? rqst->rq_xid : 0;
 		__entry->status = status;
 		__entry->flags = rqst->rq_flags;
+		memcpy(__get_dynamic_array(addr),
+			&rqst->rq_addr, rqst->rq_addrlen);
 	),
 
-	TP_printk("addr=%pIScp xid=0x%x status=%d flags=%s", __entry->addr,
+	TP_printk("addr=%pIScp xid=0x%x status=%d flags=%s",
+			(struct sockaddr *)__get_dynamic_array(addr),
 			be32_to_cpu(__entry->xid), __entry->status,
 			show_rqstp_flags(__entry->flags))
 );
@@ -513,22 +515,23 @@ DECLARE_EVENT_CLASS(svc_rqst_status,
 	TP_ARGS(rqst, status),
 
 	TP_STRUCT__entry(
-		__field(struct sockaddr *, addr)
 		__field(__be32, xid)
-		__field(int, dropme)
 		__field(int, status)
 		__field(unsigned long, flags)
+		__dynamic_array(unsigned char, addr, rqst->rq_addrlen)
 	),
 
 	TP_fast_assign(
-		__entry->addr = (struct sockaddr *)&rqst->rq_addr;
 		__entry->xid = rqst->rq_xid;
 		__entry->status = status;
 		__entry->flags = rqst->rq_flags;
+		memcpy(__get_dynamic_array(addr),
+			&rqst->rq_addr, rqst->rq_addrlen);
 	),
 
 	TP_printk("addr=%pIScp rq_xid=0x%x status=%d flags=%s",
-		__entry->addr, be32_to_cpu(__entry->xid),
+		(struct sockaddr *)__get_dynamic_array(addr),
+		be32_to_cpu(__entry->xid),
 		__entry->status, show_rqstp_flags(__entry->flags))
 );