evlist__alloc_aggr_stats
if (evlist__alloc_aggr_stats(evsel->evlist, stat_config.aggr_map->nr) < 0)
if (evlist__alloc_aggr_stats(session->evlist, nr_aggr) < 0) {
evlist__alloc_aggr_stats(evlist, 1);
evlist__alloc_aggr_stats(evlist, 1);
int evlist__alloc_aggr_stats(struct evlist *evlist, int nr_aggr);