#ifdef CONFIG_HOTPLUG_CPU /* Already up, and in cpu_quiescent now? */ if (cpu_isset(cpu, smp_commenced_mask)) { cpu_enable(cpu); return 0; } #endif  
int __devinit __cpu_up(unsigned int cpu){	/* In case one didn't come up */	if (!cpu_isset(cpu, cpu_callin_map)) {		printk(KERN_DEBUG "skipping cpu%d, didn't come online\n", cpu);		local_irq_enable();		return -EIO;	}#ifdef CONFIG_HOTPLUG_CPU	/* Already up, and in cpu_quiescent now? */	if (cpu_isset(cpu, smp_commenced_mask)) {		cpu_enable(cpu);		return 0;	}#endif	local_irq_enable();	/* Unleash the 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/e1367daf3eed5cd619ee88c9907e1e6ddaa58406/smpboot.c/clean/arch/i386/kernel/smpboot.c