trace_syscalls: Set event_enter_##sname->data to its metadata

Set event_enter_##sname->data to its metadata,
it makes codes simpler.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: Jason Baron <jbaron@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4B14D282.7050709@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index 2f7c539..d3c9fd0 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -153,6 +153,7 @@
 #define __SC_STR_TDECL6(t, a, ...)	#t, __SC_STR_TDECL5(__VA_ARGS__)
 
 #define SYSCALL_TRACE_ENTER_EVENT(sname)				\
+	static const struct syscall_metadata __syscall_meta_##sname;	\
 	static struct ftrace_event_call event_enter_##sname;		\
 	struct trace_event enter_syscall_print_##sname = {		\
 		.trace                  = print_syscall_enter,		\
@@ -184,11 +185,12 @@
 		.define_fields		= syscall_enter_define_fields,	\
 		.regfunc		= reg_event_syscall_enter,	\
 		.unregfunc		= unreg_event_syscall_enter,	\
-		.data			= "sys"#sname,			\
+		.data			= (void *)&__syscall_meta_##sname,\
 		TRACE_SYS_ENTER_PROFILE_INIT(sname)			\
 	}
 
 #define SYSCALL_TRACE_EXIT_EVENT(sname)					\
+	static const struct syscall_metadata __syscall_meta_##sname;	\
 	static struct ftrace_event_call event_exit_##sname;		\
 	struct trace_event exit_syscall_print_##sname = {		\
 		.trace                  = print_syscall_exit,		\
@@ -220,7 +222,7 @@
 		.define_fields		= syscall_exit_define_fields,	\
 		.regfunc		= reg_event_syscall_exit,	\
 		.unregfunc		= unreg_event_syscall_exit,	\
-		.data			= "sys"#sname,			\
+		.data			= (void *)&__syscall_meta_##sname,\
 		TRACE_SYS_EXIT_PROFILE_INIT(sname)			\
 	}