perf evsel: Introduce perf_evsel__{in,ex}it

Out of the {con,des}structor, as in interpreted language bindings we will
need to go back from the wrapper object to the real thing. In that case
using container_of will save us to have an extra pointer in the perf_evsel
struct.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index a85ae12..76ab553 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -14,15 +14,20 @@
 #define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
 #define SID(e, x, y) xyarray__entry(e->id, x, y)
 
+void perf_evsel__init(struct perf_evsel *evsel,
+		      struct perf_event_attr *attr, int idx)
+{
+	evsel->idx	   = idx;
+	evsel->attr	   = *attr;
+	INIT_LIST_HEAD(&evsel->node);
+}
+
 struct perf_evsel *perf_evsel__new(struct perf_event_attr *attr, int idx)
 {
 	struct perf_evsel *evsel = zalloc(sizeof(*evsel));
 
-	if (evsel != NULL) {
-		evsel->idx	   = idx;
-		evsel->attr	   = *attr;
-		INIT_LIST_HEAD(&evsel->node);
-	}
+	if (evsel != NULL)
+		perf_evsel__init(evsel, attr, idx);
 
 	return evsel;
 }
@@ -87,11 +92,16 @@
 	return evlist->mmap != NULL ? 0 : -ENOMEM;
 }
 
-void perf_evsel__delete(struct perf_evsel *evsel)
+void perf_evsel__exit(struct perf_evsel *evsel)
 {
 	assert(list_empty(&evsel->node));
 	xyarray__delete(evsel->fd);
 	xyarray__delete(evsel->id);
+}
+
+void perf_evsel__delete(struct perf_evsel *evsel)
+{
+	perf_evsel__exit(evsel);
 	free(evsel);
 }