perf scripting: Add 'flush' callback to scripting API

In order to defer some output via the scripting API, there needs to be a
callback after session processing but before the session is deleted.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1408129739-17368-3-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/trace-event-scripting.c b/tools/perf/util/trace-event-scripting.c
index 57aaccc..5c9bdd1 100644
--- a/tools/perf/util/trace-event-scripting.c
+++ b/tools/perf/util/trace-event-scripting.c
@@ -30,6 +30,11 @@
 
 struct scripting_context *scripting_context;
 
+static int flush_script_unsupported(void)
+{
+	return 0;
+}
+
 static int stop_script_unsupported(void)
 {
 	return 0;
@@ -74,6 +79,7 @@
 struct scripting_ops python_scripting_unsupported_ops = {
 	.name = "Python",
 	.start_script = python_start_script_unsupported,
+	.flush_script = flush_script_unsupported,
 	.stop_script = stop_script_unsupported,
 	.process_event = process_event_unsupported,
 	.generate_script = python_generate_script_unsupported,
@@ -137,6 +143,7 @@
 struct scripting_ops perl_scripting_unsupported_ops = {
 	.name = "Perl",
 	.start_script = perl_start_script_unsupported,
+	.flush_script = flush_script_unsupported,
 	.stop_script = stop_script_unsupported,
 	.process_event = process_event_unsupported,
 	.generate_script = perl_generate_script_unsupported,