static __u64 get_key32_value64_percpu(int fd, __u32 key)
{
	/* For PERCPU maps, userspace gets a value per possible CPU */
	unsigned int nr_cpus = bpf_num_possible_cpus();
	__u64 values[nr_cpus];
	__u64 sum = 0;
	int i;

	if ((bpf_map_lookup_elem(fd, &key, values)) != 0) {
		fprintf(stderr,
		 "ERR: bpf_map_lookup_elem failed key:0x%X\n", key);
		return 0;
	}

	/* Sum values from each CPU */
	for (i = 0; i < nr_cpus; i++) {
		sum += values[i];
	}
	return sum;
}