perf_evsel__alloc_fd
perf_evsel__alloc_fd(evsel, perf_cpu_map__nr(cpus), threads->nr) < 0)
int perf_evsel__alloc_fd(struct perf_evsel *evsel, int ncpus, int nthreads);
perf_evsel__alloc_fd(&evsel->core, perf_cpu_map__nr(cpus), nthreads) < 0)