perf probe: Split add_perf_probe_events()

The add_perf_probe_events() does 3 things:

 1. convert all perf events to trace events
 2. add all trace events to kernel
 3. cleanup all trace events

But sometimes we need to do something with the trace events.  So split
the funtion into three, so that it can access intermediate trace events
via struct __event_package if needed.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1441368963-11565-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/probe-event.c

@@ -2765,9 +2765,10 @@ struct __event_package {
 	int				ntevs;
 };
 
-int add_perf_probe_events(struct perf_probe_event *pevs, int npevs)
+static int convert_perf_probe_events(struct perf_probe_event *pevs, int npevs,
+				     struct __event_package **ppkgs)
 {
-	int i, j, ret;
+	int i, ret;
 	struct __event_package *pkgs;
 
 	ret = 0;
@@ -2792,12 +2793,21 @@ int add_perf_probe_events(struct perf_probe_event *pevs, int npevs)
 		ret  = convert_to_probe_trace_events(pkgs[i].pev,
 						     &pkgs[i].tevs);
 		if (ret < 0)
-			goto end;
+			return ret;
 		pkgs[i].ntevs = ret;
 	}
 	/* This just release blacklist only if allocated */
 	kprobe_blacklist__release();
 
+	*ppkgs = pkgs;
+
+	return 0;
+}
+
+static int apply_perf_probe_events(struct __event_package *pkgs, int npevs)
+{
+	int i, ret = 0;
+
 	/* Loop 2: add all events */
 	for (i = 0; i < npevs; i++) {
 		ret = __add_probe_trace_events(pkgs[i].pev, pkgs[i].tevs,
@@ -2806,7 +2816,16 @@ int add_perf_probe_events(struct perf_probe_event *pevs, int npevs)
 		if (ret < 0)
 			break;
 	}
-end:
+	return ret;
+}
+
+static void cleanup_perf_probe_events(struct __event_package *pkgs, int npevs)
+{
+	int i, j;
+
+	if (pkgs == NULL)
+		return;
+
 	/* Loop 3: cleanup and free trace events  */
 	for (i = 0; i < npevs; i++) {
 		for (j = 0; j < pkgs[i].ntevs; j++)
@@ -2815,6 +2834,18 @@ end:
 	}
 	free(pkgs);
 	exit_symbol_maps();
+}
+
+int add_perf_probe_events(struct perf_probe_event *pevs, int npevs)
+{
+	int ret;
+	struct __event_package *pkgs = NULL;
+
+	ret = convert_perf_probe_events(pevs, npevs, &pkgs);
+	if (ret == 0)
+		ret = apply_perf_probe_events(pkgs, npevs);
+
+	cleanup_perf_probe_events(pkgs, npevs);
 
 	return ret;
 }