parent = &node_devices[cpu_to_node(cpu)]; 
/* The node to which a cpu belongs can't be known * until the cpu is made present. */ parent = NULL; if (cpu_present(cpu)) parent = &node_devices[cpu_to_node(cpu)]; 
static int __init topology_init(void){	int cpu;	struct node *parent = NULL;	register_nodes();	register_cpu_notifier(&sysfs_cpu_nb);	for_each_cpu(cpu) {		struct cpu *c = &per_cpu(cpu_devices, cpu);#ifdef CONFIG_NUMA		parent = &node_devices[cpu_to_node(cpu)];#endif		/*		 * For now, we just see if the system supports making		 * the RTAS calls for CPU hotplug.  But, there may be a		 * more comprehensive way to do this for an individual		 * CPU.  For instance, the boot cpu might never be valid		 * for hotplugging.		 */		if (!ppc_md.cpu_die)			c->no_control = 1;		if (cpu_online(cpu) || (c->no_control == 0)) {			register_cpu(c, cpu, parent);			sysdev_create_file(&c->sysdev, &attr_physical_id);		}		if (cpu_online(cpu))			register_cpu_online(cpu);	}	return 0;}
4520	/local/tlutelli/issta_data/temp/c/2005_temp/2005/4520/f5f1cc5437961a4bd93d615099f26780819e72d3/sysfs.c/buggy/arch/ppc64/kernel/sysfs.c