kerneldoc, tracing: make kernel-doc understand TRACE_EVENT() macro (take #2)

Add support to kernel-doc for tracepoint comments above TRACE_EVENT()
macro definitions. Paves the way for tracepoint docbook.

[ Impact: extend DocBook infrastructure ]

Signed-off-by: Jason Baron <jbaron@redhat.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: akpm@linux-foundation.org
Cc: rostedt@goodmis.org
Cc: fweisbec@gmail.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: wcohen@redhat.com
LKML-Reference: <d80706b6797e277924d2f3ec9af176c6b2951f88.1241107197.git.jbaron@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/scripts/kernel-doc b/scripts/kernel-doc
index 0f11870..2b53a55 100755
--- a/scripts/kernel-doc
+++ b/scripts/kernel-doc
@@ -1827,6 +1827,25 @@
     $state = 0;
 }
 
+sub tracepoint_munge($) {
+	my $file = shift;
+	my $tracepointname = 0;
+	my $tracepointargs = 0;
+
+	if($prototype =~ m/TRACE_EVENT\((.*?),/) {
+		$tracepointname = $1;
+	}
+	if($prototype =~ m/TP_PROTO\((.*?)\)/) {
+		$tracepointargs = $1;
+	}
+	if (($tracepointname eq 0) || ($tracepointargs eq 0)) {
+		print STDERR "Warning(${file}:$.): Unrecognized tracepoint format: \n".
+			     "$prototype\n";
+	} else {
+		$prototype = "static inline void trace_$tracepointname($tracepointargs)";
+	}
+}
+
 sub syscall_munge() {
 	my $void = 0;
 
@@ -1881,6 +1900,9 @@
 	if ($prototype =~ /SYSCALL_DEFINE/) {
 		syscall_munge();
 	}
+	if ($prototype =~ /TRACE_EVENT/) {
+		tracepoint_munge($file);
+	}
 	dump_function($prototype, $file);
 	reset_state();
     }