perf tools: Refactor unit and scale function parameters

Passing pointers to alias modifiers 'unit' and 'scale' isn't very
future-proof since if we add more modifiers to the list we'll end up
passing more arguments.

Instead wrap everything up in a struct perf_pmu_info, which can easily
be expanded when additional alias modifiers are necessary in the future.

Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1411567455-31264-3-git-send-email-matt@console-pimps.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 61be3e6..9522cf2 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -634,10 +634,9 @@
 			 char *name, struct list_head *head_config)
 {
 	struct perf_event_attr attr;
+	struct perf_pmu_info info;
 	struct perf_pmu *pmu;
 	struct perf_evsel *evsel;
-	const char *unit;
-	double scale;
 
 	pmu = perf_pmu__find(name);
 	if (!pmu)
@@ -656,7 +655,7 @@
 		return evsel ? 0 : -ENOMEM;
 	}
 
-	if (perf_pmu__check_alias(pmu, head_config, &unit, &scale))
+	if (perf_pmu__check_alias(pmu, head_config, &info))
 		return -EINVAL;
 
 	/*
@@ -671,8 +670,8 @@
 	evsel = __add_event(list, idx, &attr, pmu_event_name(head_config),
 			    pmu->cpus);
 	if (evsel) {
-		evsel->unit = unit;
-		evsel->scale = scale;
+		evsel->unit = info.unit;
+		evsel->scale = info.scale;
 	}
 
 	return evsel ? 0 : -ENOMEM;