perf tools: Add support to specify pmu style event

Added new event rule to the event definition grammar:

event_def: event_pmu |
           ...
event_pmu: PE_NAME '/' event_config '/'

Using this rule, event could be now specified like:
  cpu/config=1,config1=2,config2=3/u

where pmu name 'cpu' is looked up via following path:
  ${sysfs_mount}/bus/event_source/devices/${pmu}

and config options are bound to the pmu's format definiton:
  ${sysfs_mount}/bus/event_source/devices/${pmu}/format

The hardcoded config options still stays and have precedence
over any format field defined with same name.

Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/n/tip-50d8nr94f8k4wkezutrxvthe@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-test.c

@@ -877,6 +877,22 @@ static int test__checkevent_genhw_modifier(struct perf_evlist *evlist)
 	return test__checkevent_genhw(evlist);
 }
 
+static int test__checkevent_pmu(struct perf_evlist *evlist)
+{
+
+	struct perf_evsel *evsel = list_entry(evlist->entries.next,
+					      struct perf_evsel, node);
+
+	TEST_ASSERT_VAL("wrong number of entries", 1 == evlist->nr_entries);
+	TEST_ASSERT_VAL("wrong type", PERF_TYPE_RAW == evsel->attr.type);
+	TEST_ASSERT_VAL("wrong config",    10 == evsel->attr.config);
+	TEST_ASSERT_VAL("wrong config1",    1 == evsel->attr.config1);
+	TEST_ASSERT_VAL("wrong config2",    3 == evsel->attr.config2);
+	TEST_ASSERT_VAL("wrong period",  1000 == evsel->attr.sample_period);
+
+	return 0;
+}
+
 static struct test__event_st {
 	const char *name;
 	__u32 type;
@@ -958,6 +974,10 @@ static struct test__event_st {
 		.name  = "L1-dcache-load-miss:kp",
 		.check = test__checkevent_genhw_modifier,
 	},
+	{
+		.name  = "cpu/config=10,config1,config2=3,period=1000/u",
+		.check = test__checkevent_pmu,
+	},
 };
 
 #define TEST__EVENTS_CNT (sizeof(test__events) / sizeof(struct test__event_st))