NFS: nfs_xdr_status should record the procedure name

When sunrpc trace points are not enabled, the recorded task ID
information alone is not helpful.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

fs/nfs/nfstrace.h

@@ -1312,7 +1312,12 @@ TRACE_EVENT(nfs_xdr_status,
 			__field(unsigned int, task_id)
 			__field(unsigned int, client_id)
 			__field(u32, xid)
+			__field(int, version)
 			__field(unsigned long, error)
+			__string(program,
+				 xdr->rqst->rq_task->tk_client->cl_program->name)
+			__string(procedure,
+				 xdr->rqst->rq_task->tk_msg.rpc_proc->p_name)
 		),
 
 		TP_fast_assign(
@@ -1322,13 +1327,19 @@ TRACE_EVENT(nfs_xdr_status,
 			__entry->task_id = task->tk_pid;
 			__entry->client_id = task->tk_client->cl_clid;
 			__entry->xid = be32_to_cpu(rqstp->rq_xid);
+			__entry->version = task->tk_client->cl_vers;
 			__entry->error = error;
+			__assign_str(program,
+				     task->tk_client->cl_program->name)
+			__assign_str(procedure, task->tk_msg.rpc_proc->p_name)
 		),
 
 		TP_printk(
-			"task:%u@%d xid=0x%08x error=%ld (%s)",
+			"task:%u@%d xid=0x%08x %sv%d %s error=%ld (%s)",
 			__entry->task_id, __entry->client_id, __entry->xid,
-			-__entry->error, nfs_show_status(__entry->error)
+			__get_str(program), __entry->version,
+			__get_str(procedure), -__entry->error,
+			nfs_show_status(__entry->error)
 		)
 );