perf evsel: Convert to _is_group_leader method

Convert perf_evsel__is_group_member to perf_evsel__is_group_leader.
This is because the most usecases are using negative form to check
whether the given evsel is a leader or not and it's IMHO somewhat
ambiguous - leader also *is* a member of the group.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1354171126-14387-4-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index cbf6d97..3f7ff47 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -226,8 +226,8 @@
 	return list_entry(evsel->node.next, struct perf_evsel, node);
 }
 
-static inline bool perf_evsel__is_group_member(const struct perf_evsel *evsel)
+static inline bool perf_evsel__is_group_leader(const struct perf_evsel *evsel)
 {
-	return evsel->leader != evsel;
+	return evsel->leader == evsel;
 }
 #endif /* __PERF_EVSEL_H */