arch/i386/kernel/topology.c

   1 /*
   2  * arch/i386/kernel/topology.c - Populate driverfs 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 <asm/cpu.h>
  32
  33 static struct i386_cpu cpu_devices[NR_CPUS];
  34
  35 int arch_register_cpu(int num){
  36         struct node *parent = NULL;
  37
  38 #ifdef CONFIG_NUMA
  39         int node = cpu_to_node(num);
  40         if (node_online(node))
  41                 parent = &node_devices[parent_node(node)];
  42 #endif /* CONFIG_NUMA */
  43
  44         /*
  45          * CPU0 cannot be offlined due to several
  46          * restrictions and assumptions in kernel. This basically
  47          * doesnt add a control file, one cannot attempt to offline
  48          * BSP.
  49          */
  50         if (!num)
  51                 cpu_devices[num].cpu.no_control = 1;
  52
  53         return register_cpu(&cpu_devices[num].cpu, num, parent);
  54 }
  55
  56 #ifdef CONFIG_HOTPLUG_CPU
  57
  58 void arch_unregister_cpu(int num) {
  59         struct node *parent = NULL;
  60
  61 #ifdef CONFIG_NUMA
  62         int node = cpu_to_node(num);
  63         if (node_online(node))
  64                 parent = &node_devices[parent_node(node)];
  65 #endif /* CONFIG_NUMA */
  66
  67         return unregister_cpu(&cpu_devices[num].cpu, parent);
  68 }
  69 EXPORT_SYMBOL(arch_register_cpu);
  70 EXPORT_SYMBOL(arch_unregister_cpu);
  71 #endif /*CONFIG_HOTPLUG_CPU*/
  72
  73
  74
  75 #ifdef CONFIG_NUMA
  76 #include <linux/mmzone.h>
  77
  78 static int __init topology_init(void)
  79 {
  80         int i;
  81
  82         for_each_online_node(i)
  83                 register_one_node(i);
  84
  85         for_each_present_cpu(i)
  86                 arch_register_cpu(i);
  87         return 0;
  88 }
  89
  90 #else /* !CONFIG_NUMA */
  91
  92 static int __init topology_init(void)
  93 {
  94         int i;
  95
  96         for_each_present_cpu(i)
  97                 arch_register_cpu(i);
  98         return 0;
  99 }
 100
 101 #endif /* CONFIG_NUMA */
 102
 103 subsys_initcall(topology_init);