perf evsel: Set leader evsel's ->leader to itself

Currently only non-leader members are set ->leader to the leader evsel
of the group and the leader has set NULL.  Thus it requires special
casing for leader evsels.  Set ->leader to itself will remove this.

Suggested-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
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/1354171126-14387-3-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index 7052934..90db2a1 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -111,7 +111,6 @@
 	struct perf_evsel *evsel, *leader;
 
 	leader = list_entry(list->next, struct perf_evsel, node);
-	leader->leader = NULL;
 
 	list_for_each_entry(evsel, list, node) {
 		if (evsel != leader)
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 1b16dd1..7e93418 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -55,6 +55,7 @@
 {
 	evsel->idx	   = idx;
 	evsel->attr	   = *attr;
+	evsel->leader	   = evsel;
 	INIT_LIST_HEAD(&evsel->node);
 	hists__init(&evsel->hists);
 	evsel->sample_size = __perf_evsel__sample_size(attr->sample_type);
diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index 3d2b801..cbf6d97 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -228,6 +228,6 @@
 
 static inline bool perf_evsel__is_group_member(const struct perf_evsel *evsel)
 {
-	return evsel->leader != NULL;
+	return evsel->leader != evsel;
 }
 #endif /* __PERF_EVSEL_H */