start_cpu
if (start_cpu(who) != 0)
extern int start_cpu(processorid_t);
error = start_cpu(id);
struct cpu *start_cpu;
cp = start_cpu = curr_cpu->cpu_next_onln;
} while ((cp = cp->cpu_next_onln) != start_cpu);
start_cpu(cpuid, warm_flag_set);
start_cpu(cpuid, cold_flag_set);