perf probe: Change event list format

Change event list format for user readability. perf probe --list
shows event list in "[GROUP:EVENT] EVENT-DEFINITION" format, but
this format is different from the output of perf-list, and
EVENT-DEFINITION is a bit blunt. This patch changes the format to
more user friendly one.

Before:
[probe:schedule_0]	schedule+10 prev cpu

After:
  probe:schedule_0                         (on schedule+10 with prev cpu)

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
LKML-Reference: <20091208220240.10142.42916.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 88e1804..a20e382 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -379,11 +379,29 @@
 	memset(pp, 0, sizeof(pp));
 }
 
+/* Show an event */
+static void show_perf_probe_event(const char *group, const char *event,
+				  const char *place, struct probe_point *pp)
+{
+	int i;
+	char buf[128];
+
+	e_snprintf(buf, 128, "%s:%s", group, event);
+	printf("  %-40s (on %s", buf, place);
+
+	if (pp->nr_args > 0) {
+		printf(" with");
+		for (i = 0; i < pp->nr_args; i++)
+			printf(" %s", pp->args[i]);
+	}
+	printf(")\n");
+}
+
 /* List up current perf-probe events */
 void show_perf_probe_events(void)
 {
 	unsigned int i;
-	int fd;
+	int fd, nr;
 	char *group, *event;
 	struct probe_point pp;
 	struct strlist *rawlist;
@@ -396,8 +414,13 @@
 	for (i = 0; i < strlist__nr_entries(rawlist); i++) {
 		ent = strlist__entry(rawlist, i);
 		parse_trace_kprobe_event(ent->s, &group, &event, &pp);
+		/* Synthesize only event probe point */
+		nr = pp.nr_args;
+		pp.nr_args = 0;
 		synthesize_perf_probe_event(&pp);
-		printf("[%s:%s]\t%s\n", group, event, pp.probes[0]);
+		pp.nr_args = nr;
+		/* Show an event */
+		show_perf_probe_event(group, event, pp.probes[0], &pp);
 		free(group);
 		free(event);
 		clear_probe_point(&pp);