initialize_cpu_set_from_sysfs
initialize_cpu_set_from_sysfs(perf_pcore_set, perf_cpu_pcore_path, "cpus");
initialize_cpu_set_from_sysfs(perf_ecore_set, perf_cpu_ecore_path, "cpus");
initialize_cpu_set_from_sysfs(perf_lcore_set, perf_cpu_lcore_path, "cpus");
initialize_cpu_set_from_sysfs(cpu_possible_set, "/sys/devices/system/cpu", "possible");