1 /* 2 * Populate sysfs with topology information 3 * 4 * Written by: Matthew Dobson, IBM Corporation 5 * Original Code: Paul Dorwin, IBM Corporation, Patrick Mochel, OSDL 6 * 7 * Copyright (C) 2002, IBM Corp. 8 * 9 * All rights reserved. 10 * 11 * This program is free software; you can redistribute it and/or modify 12 * it under the terms of the GNU General Public License as published by 13 * the Free Software Foundation; either version 2 of the License, or 14 * (at your option) any later version. 15 * 16 * This program is distributed in the hope that it will be useful, but 17 * WITHOUT ANY WARRANTY; without even the implied warranty of 18 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or 19 * NON INFRINGEMENT. See the GNU General Public License for more 20 * details. 21 * 22 * You should have received a copy of the GNU General Public License 23 * along with this program; if not, write to the Free Software 24 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 25 * 26 * Send feedback to <colpatch@us.ibm.com> 27 */ 28 #include <linux/init.h> 29 #include <linux/smp.h> 30 #include <linux/nodemask.h> 31 #include <linux/mmzone.h> 32 #include <asm/cpu.h> 33 34 static DEFINE_PER_CPU(struct x86_cpu, cpu_devices); 35 36 #ifdef CONFIG_HOTPLUG_CPU 37 int __ref arch_register_cpu(int num) 38 { 39 /* 40 * CPU0 cannot be offlined due to several 41 * restrictions and assumptions in kernel. This basically 42 * doesnt add a control file, one cannot attempt to offline 43 * BSP. 44 * 45 * Also certain PCI quirks require not to enable hotplug control 46 * for all CPU's. 47 */ 48 if (num) 49 per_cpu(cpu_devices, num).cpu.hotpluggable = 1; 50 return register_cpu(&per_cpu(cpu_devices, num).cpu, num); 51 } 52 EXPORT_SYMBOL(arch_register_cpu); 53 54 void arch_unregister_cpu(int num) 55 { 56 unregister_cpu(&per_cpu(cpu_devices, num).cpu); 57 } 58 EXPORT_SYMBOL(arch_unregister_cpu); 59 #else 60 static int __init arch_register_cpu(int num) 61 { 62 return register_cpu(&per_cpu(cpu_devices, num).cpu, num); 63 } 64 #endif /*CONFIG_HOTPLUG_CPU*/ 65 66 static int __init topology_init(void) 67 { 68 int i; 69 70 #ifdef CONFIG_NUMA 71 for_each_online_node(i) 72 register_one_node(i); 73 #endif /* CONFIG_NUMA */ 74 75 for_each_present_cpu(i) 76 arch_register_cpu(i); 77 return 0; 78 } 79 80 subsys_initcall(topology_init); 81