x86/tlb/trace: Export enums in used by tlb_flush tracepoint

Have the enums used in __print_symbolic() by the trace_tlb_flush()
tracepoint exported to userpace such that they can be parsed by
userspace tools.

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

Cc: Dave Hansen <dave@sr71.net>
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/tlb.h

@@ -7,11 +7,31 @@
 #include <linux/mm_types.h>
 #include <linux/tracepoint.h>
 
-#define TLB_FLUSH_REASON	\
-	{ TLB_FLUSH_ON_TASK_SWITCH,	"flush on task switch" },	\
-	{ TLB_REMOTE_SHOOTDOWN,		"remote shootdown" },		\
-	{ TLB_LOCAL_SHOOTDOWN,		"local shootdown" },		\
-	{ TLB_LOCAL_MM_SHOOTDOWN,	"local mm shootdown" }
+#define TLB_FLUSH_REASON						\
+	EM(  TLB_FLUSH_ON_TASK_SWITCH,	"flush on task switch" )	\
+	EM(  TLB_REMOTE_SHOOTDOWN,	"remote shootdown" )		\
+	EM(  TLB_LOCAL_SHOOTDOWN,	"local shootdown" )		\
+	EMe( TLB_LOCAL_MM_SHOOTDOWN,	"local mm shootdown" )
+
+/*
+ * First define the enums in TLB_FLUSH_REASON to be exported 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);
+
+TLB_FLUSH_REASON
+
+/*
+ * 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 }
 
 TRACE_EVENT_CONDITION(tlb_flush,