Re: [PATCH] perf/tool: Fix usage of trace events with '-' in trace system name.

[Alexander Yarygin <yarygin@linux.vnet.ibm.com>]

At Thu, 17 Apr 2014 13:32:21 +0200,
Jiri Olsa wrote:
> 
> On Tue, Mar 25, 2014 at 11:15:29AM +0100, Paolo Bonzini wrote:
> > Il 24/03/2014 21:49, Christian Borntraeger ha scritto:
> > > event_legacy_tracepoint:
> > >+PE_NAME '-' PE_NAME ':' PE_NAME
> > >+{
> > >+	struct parse_events_evlist *data = _data;
> > >+	struct list_head *list;
> > >+	char sys_name[strlen($1) + strlen($3) + 2];
> > >+	sprintf(&sys_name, "%s-%s", $1, $3);
> > >+
> > >+	ALLOC_LIST(list);
> > >+	ABORT_ON(parse_events_add_tracepoint(list, &data->idx, &sys_name, $5));
> > >+	$$ = list;
> > >+}
> > 
> > Why isn't '-' part of PE_NAME?
> 
> hi Paolo ;-)
> 
> because it screws cache events parsing.. we need some code factoring
> in this part
> 
> Acked-by: Jiri Olsa <jolsa@redhat.com>
> 
> it'd be nice to add test to tests/parse-events.c, probably s390 specific,
> because the parsing code touches the tracepoint format file
> 

Hi,

Hmm, looks like we can't simply add arch-specific test:

--- a/tools/perf/tests/parse-events.c
+++ b/tools/perf/tests/parse-events.c
@@ -1346,6 +1346,12 @@ static struct evlist_test test__events[] = {
 		.name  = "{cycles,cache-misses,branch-misses}:D",
 		.check = test__pinned_group,
 	},
+#if defined(__s390x__)
+	[42] = {
+		.name  = "kvm-s390:kvm_s390_create_vm",
+		.check = test__checkevent_tracepoint,
+	},
+#endif /* and what will be the next number: 42 or 43? */
 };

 static struct evlist_test test__events_pmu[] = {


Because it breaks explicit numbering of test__events[].
I can suggest to move numeration into evlist_test, i.e.

--- a/tools/perf/tests/parse-events.c
+++ b/tools/perf/tests/parse-events.c
@@ -1174,25 +1174,30 @@ static int test__all_tracepoints(struct perf_evlist *evlist)
 struct evlist_test {
 	const char *name;
 	__u32 type;
+	int index;
 	int (*check)(struct perf_evlist *evlist);
 };
 
 static struct evlist_test test__events[] = {
-	[0] = {
+	{
 		.name  = "syscalls:sys_enter_open",
 		.check = test__checkevent_tracepoint,
+		.index = 0;
 	},
...

or just to remove it?

How do you think?


And a bit of offtopic :)
Apparently, s390 doesn't have syscalls:*, so some of the tests
don't work properly (or maybe I missed something? I set CONFIG_FTRACE_SYSCALLS
to 'y' in my config: still no syscalls:*).

What do you think about this idea:

--- a/tools/perf/tests/parse-events.c
+++ b/tools/perf/tests/parse-events.c
@@ -1177,13 +1177,21 @@ struct evlist_test {
 	int (*check)(struct perf_evlist *evlist);
 };

+#if !defined(__s390x__)
+#define TP_SYS_NAME "syscalls"
+#define TP_EVENT_NAME "sys_enter_open"
+#else
+#define TP_SYS_NAME "sched"
+#define TP_EVENT_NAME "sched_wakeup"
+#endif
+
 static struct evlist_test test__events[] = {
 	[0] = {
-		.name  = "syscalls:sys_enter_open",
+		.name  = TP_SYS_NAME ":" TP_EVENT_NAME,
 		.check = test__checkevent_tracepoint,
 	},

... and so on?

Also, test_pmu() looks at /sys/bus/event_source/devices/cpu/
but instead of "cpu/" on s390 there are "cpum_sf/" and "cpum_cf/",
so pmu tests don't work either..


Thanks