cpu_set(cpu, smp_commenced_mask); 
int __devinit __cpu_up(unsigned int cpu){	/* This only works at boot for x86.  See "rewrite" above. */	if (cpu_isset(cpu, smp_commenced_mask)) {		local_irq_enable();		return -ENOSYS;	}	/* In case one didn't come up */	if (!cpu_isset(cpu, cpu_callin_map)) {		local_irq_enable();		return -EIO;	}	local_irq_enable();	/* Unleash the CPU! */	Dprintk("waiting for cpu %d\n", cpu);	cpu_set(cpu, smp_commenced_mask);	while (!cpu_isset(cpu, cpu_online_map))		mb();	return 0;}
4520	/local/tlutelli/issta_data/temp/c/2005_temp/2005/4520/a8ab26fe5bfeef43bdcde5182ca051ae0647607e/smpboot.c/clean/arch/x86_64/kernel/smpboot.c