net/9p/tracing: Export enums in tracepoints to userspace

The tracepoints in the 9p code use a lot of enums for the __print_symbolic()
function. These enums are shown in the tracepoint format files, and user
space tools such as trace-cmd does not have the information to parse it.
Add helper macros to export the enums with TRACE_DEFINE_ENUM().

Link: http://lkml.kernel.org/r/20150403013802.220157513@goodmis.org

Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

include/trace/events/9p.h

@@ -6,76 +6,95 @@
 
 #include <linux/tracepoint.h>
 
+#define P9_MSG_T							\
+		EM( P9_TLERROR,		"P9_TLERROR" )			\
+		EM( P9_RLERROR,		"P9_RLERROR" )			\
+		EM( P9_TSTATFS,		"P9_TSTATFS" )			\
+		EM( P9_RSTATFS,		"P9_RSTATFS" )			\
+		EM( P9_TLOPEN,		"P9_TLOPEN" )			\
+		EM( P9_RLOPEN,		"P9_RLOPEN" )			\
+		EM( P9_TLCREATE,	"P9_TLCREATE" )			\
+		EM( P9_RLCREATE,	"P9_RLCREATE" )			\
+		EM( P9_TSYMLINK,	"P9_TSYMLINK" )			\
+		EM( P9_RSYMLINK,	"P9_RSYMLINK" )			\
+		EM( P9_TMKNOD,		"P9_TMKNOD" )			\
+		EM( P9_RMKNOD,		"P9_RMKNOD" )			\
+		EM( P9_TRENAME,		"P9_TRENAME" )			\
+		EM( P9_RRENAME,		"P9_RRENAME" )			\
+		EM( P9_TREADLINK,	"P9_TREADLINK" )		\
+		EM( P9_RREADLINK,	"P9_RREADLINK" )		\
+		EM( P9_TGETATTR,	"P9_TGETATTR" )			\
+		EM( P9_RGETATTR,	"P9_RGETATTR" )			\
+		EM( P9_TSETATTR,	"P9_TSETATTR" )			\
+		EM( P9_RSETATTR,	"P9_RSETATTR" )			\
+		EM( P9_TXATTRWALK,	"P9_TXATTRWALK" )		\
+		EM( P9_RXATTRWALK,	"P9_RXATTRWALK" )		\
+		EM( P9_TXATTRCREATE,	"P9_TXATTRCREATE" )		\
+		EM( P9_RXATTRCREATE,	"P9_RXATTRCREATE" )		\
+		EM( P9_TREADDIR,	"P9_TREADDIR" )			\
+		EM( P9_RREADDIR,	"P9_RREADDIR" )			\
+		EM( P9_TFSYNC,		"P9_TFSYNC" )			\
+		EM( P9_RFSYNC,		"P9_RFSYNC" )			\
+		EM( P9_TLOCK,		"P9_TLOCK" )			\
+		EM( P9_RLOCK,		"P9_RLOCK" )			\
+		EM( P9_TGETLOCK,	"P9_TGETLOCK" )			\
+		EM( P9_RGETLOCK,	"P9_RGETLOCK" )			\
+		EM( P9_TLINK,		"P9_TLINK" )			\
+		EM( P9_RLINK,		"P9_RLINK" )			\
+		EM( P9_TMKDIR,		"P9_TMKDIR" )			\
+		EM( P9_RMKDIR,		"P9_RMKDIR" )			\
+		EM( P9_TRENAMEAT,	"P9_TRENAMEAT" )		\
+		EM( P9_RRENAMEAT,	"P9_RRENAMEAT" )		\
+		EM( P9_TUNLINKAT,	"P9_TUNLINKAT" )		\
+		EM( P9_RUNLINKAT,	"P9_RUNLINKAT" )		\
+		EM( P9_TVERSION,	"P9_TVERSION" )			\
+		EM( P9_RVERSION,	"P9_RVERSION" )			\
+		EM( P9_TAUTH,		"P9_TAUTH" )			\
+		EM( P9_RAUTH,		"P9_RAUTH" )			\
+		EM( P9_TATTACH,		"P9_TATTACH" )			\
+		EM( P9_RATTACH,		"P9_RATTACH" )			\
+		EM( P9_TERROR,		"P9_TERROR" )			\
+		EM( P9_RERROR,		"P9_RERROR" )			\
+		EM( P9_TFLUSH,		"P9_TFLUSH" )			\
+		EM( P9_RFLUSH,		"P9_RFLUSH" )			\
+		EM( P9_TWALK,		"P9_TWALK" )			\
+		EM( P9_RWALK,		"P9_RWALK" )			\
+		EM( P9_TOPEN,		"P9_TOPEN" )			\
+		EM( P9_ROPEN,		"P9_ROPEN" )			\
+		EM( P9_TCREATE,		"P9_TCREATE" )			\
+		EM( P9_RCREATE,		"P9_RCREATE" )			\
+		EM( P9_TREAD,		"P9_TREAD" )			\
+		EM( P9_RREAD,		"P9_RREAD" )			\
+		EM( P9_TWRITE,		"P9_TWRITE" )			\
+		EM( P9_RWRITE,		"P9_RWRITE" )			\
+		EM( P9_TCLUNK,		"P9_TCLUNK" )			\
+		EM( P9_RCLUNK,		"P9_RCLUNK" )			\
+		EM( P9_TREMOVE,		"P9_TREMOVE" )			\
+		EM( P9_RREMOVE,		"P9_RREMOVE" )			\
+		EM( P9_TSTAT,		"P9_TSTAT" )			\
+		EM( P9_RSTAT,		"P9_RSTAT" )			\
+		EM( P9_TWSTAT,		"P9_TWSTAT" )			\
+		EMe(P9_RWSTAT,		"P9_RWSTAT" )
+
+/* Define EM() to export the enums to userspace via TRACE_DEFINE_ENUM() */
+#undef EM
+#undef EMe
+#define EM(a, b)	TRACE_DEFINE_ENUM(a);
+#define EMe(a, b)	TRACE_DEFINE_ENUM(a);
+
+P9_MSG_T
+
+/*
+ * Now redefine the EM() and EMe() macros to map the enums to the strings
+ * that will be printed in the output.
+ */
+#undef EM
+#undef EMe
+#define EM(a, b)	{ a, b },
+#define EMe(a, b)	{ a, b }
+
 #define show_9p_op(type)						\
-	__print_symbolic(type,						\
-			 { P9_TLERROR,		"P9_TLERROR" },		\
-			 { P9_RLERROR,		"P9_RLERROR" },		\
-			 { P9_TSTATFS,		"P9_TSTATFS" },		\
-			 { P9_RSTATFS,		"P9_RSTATFS" },		\
-			 { P9_TLOPEN,		"P9_TLOPEN" },		\
-			 { P9_RLOPEN,		"P9_RLOPEN" },		\
-			 { P9_TLCREATE,		"P9_TLCREATE" },	\
-			 { P9_RLCREATE,		"P9_RLCREATE" },	\
-			 { P9_TSYMLINK,		"P9_TSYMLINK" },	\
-			 { P9_RSYMLINK,		"P9_RSYMLINK" },	\
-			 { P9_TMKNOD,		"P9_TMKNOD" },		\
-			 { P9_RMKNOD,		"P9_RMKNOD" },		\
-			 { P9_TRENAME,		"P9_TRENAME" },		\
-			 { P9_RRENAME,		"P9_RRENAME" },		\
-			 { P9_TREADLINK,	"P9_TREADLINK" },	\
-			 { P9_RREADLINK,	"P9_RREADLINK" },	\
-			 { P9_TGETATTR,		"P9_TGETATTR" },	\
-			 { P9_RGETATTR,		"P9_RGETATTR" },	\
-			 { P9_TSETATTR,		"P9_TSETATTR" },	\
-			 { P9_RSETATTR,		"P9_RSETATTR" },	\
-			 { P9_TXATTRWALK,	"P9_TXATTRWALK" },	\
-			 { P9_RXATTRWALK,	"P9_RXATTRWALK" },	\
-			 { P9_TXATTRCREATE,	"P9_TXATTRCREATE" },	\
-			 { P9_RXATTRCREATE,	"P9_RXATTRCREATE" },	\
-			 { P9_TREADDIR,		"P9_TREADDIR" },	\
-			 { P9_RREADDIR,		"P9_RREADDIR" },	\
-			 { P9_TFSYNC,		"P9_TFSYNC" },		\
-			 { P9_RFSYNC,		"P9_RFSYNC" },		\
-			 { P9_TLOCK,		"P9_TLOCK" },		\
-			 { P9_RLOCK,		"P9_RLOCK" },		\
-			 { P9_TGETLOCK,		"P9_TGETLOCK" },	\
-			 { P9_RGETLOCK,		"P9_RGETLOCK" },	\
-			 { P9_TLINK,		"P9_TLINK" },		\
-			 { P9_RLINK,		"P9_RLINK" },		\
-			 { P9_TMKDIR,		"P9_TMKDIR" },		\
-			 { P9_RMKDIR,		"P9_RMKDIR" },		\
-			 { P9_TRENAMEAT,	"P9_TRENAMEAT" },	\
-			 { P9_RRENAMEAT,	"P9_RRENAMEAT" },	\
-			 { P9_TUNLINKAT,	"P9_TUNLINKAT" },	\
-			 { P9_RUNLINKAT,	"P9_RUNLINKAT" },	\
-			 { P9_TVERSION,		"P9_TVERSION" },	\
-			 { P9_RVERSION,		"P9_RVERSION" },	\
-			 { P9_TAUTH,		"P9_TAUTH" },		\
-			 { P9_RAUTH,		"P9_RAUTH" },		\
-			 { P9_TATTACH,		"P9_TATTACH" },		\
-			 { P9_RATTACH,		"P9_RATTACH" },		\
-			 { P9_TERROR,		"P9_TERROR" },		\
-			 { P9_RERROR,		"P9_RERROR" },		\
-			 { P9_TFLUSH,		"P9_TFLUSH" },		\
-			 { P9_RFLUSH,		"P9_RFLUSH" },		\
-			 { P9_TWALK,		"P9_TWALK" },		\
-			 { P9_RWALK,		"P9_RWALK" },		\
-			 { P9_TOPEN,		"P9_TOPEN" },		\
-			 { P9_ROPEN,		"P9_ROPEN" },		\
-			 { P9_TCREATE,		"P9_TCREATE" },		\
-			 { P9_RCREATE,		"P9_RCREATE" },		\
-			 { P9_TREAD,		"P9_TREAD" },		\
-			 { P9_RREAD,		"P9_RREAD" },		\
-			 { P9_TWRITE,		"P9_TWRITE" },		\
-			 { P9_RWRITE,		"P9_RWRITE" },		\
-			 { P9_TCLUNK,		"P9_TCLUNK" },		\
-			 { P9_RCLUNK,		"P9_RCLUNK" },		\
-			 { P9_TREMOVE,		"P9_TREMOVE" },		\
-			 { P9_RREMOVE,		"P9_RREMOVE" },		\
-			 { P9_TSTAT,		"P9_TSTAT" },		\
-			 { P9_RSTAT,		"P9_RSTAT" },		\
-			 { P9_TWSTAT,		"P9_TWSTAT" },		\
-			 { P9_RWSTAT,		"P9_RWSTAT" })
+	__print_symbolic(type, P9_MSG_T)
 
 TRACE_EVENT(9p_client_req,
 	    TP_PROTO(struct p9_client *clnt, int8_t type, int tag),