arch/x86/kernel/setup.c

   1 #include <linux/kernel.h>
   2 #include <linux/module.h>
   3 #include <linux/init.h>
   4 #include <linux/bootmem.h>
   5 #include <linux/percpu.h>
   6 #include <asm/smp.h>
   7 #include <asm/percpu.h>
   8 #include <asm/sections.h>
   9 #include <asm/processor.h>
  10 #include <asm/setup.h>
  11 #include <asm/topology.h>
  12 #include <asm/mpspec.h>
  13 #include <asm/apicdef.h>
  14
  15 unsigned int num_processors;
  16 unsigned disabled_cpus __cpuinitdata;
  17 /* Processor that is doing the boot up */
  18 unsigned int boot_cpu_physical_apicid = -1U;
  19 EXPORT_SYMBOL(boot_cpu_physical_apicid);
  20
  21 physid_mask_t phys_cpu_present_map;
  22
  23 DEFINE_PER_CPU(u16, x86_cpu_to_apicid) = BAD_APICID;
  24 EXPORT_PER_CPU_SYMBOL(x86_cpu_to_apicid);
  25
  26 /* Bitmask of physically existing CPUs */
  27 physid_mask_t phys_cpu_present_map;
  28
  29 #if defined(CONFIG_HAVE_SETUP_PER_CPU_AREA) && defined(CONFIG_SMP)
  30 /*
  31  * Copy data used in early init routines from the initial arrays to the
  32  * per cpu data areas.  These arrays then become expendable and the
  33  * *_early_ptr's are zeroed indicating that the static arrays are gone.
  34  */
  35 static void __init setup_per_cpu_maps(void)
  36 {
  37         int cpu;
  38
  39         for_each_possible_cpu(cpu) {
  40                 per_cpu(x86_cpu_to_apicid, cpu) = x86_cpu_to_apicid_init[cpu];
  41                 per_cpu(x86_bios_cpu_apicid, cpu) =
  42                                                 x86_bios_cpu_apicid_init[cpu];
  43 #ifdef CONFIG_NUMA
  44                 per_cpu(x86_cpu_to_node_map, cpu) =
  45                                                 x86_cpu_to_node_map_init[cpu];
  46 #endif
  47         }
  48
  49         /* indicate the early static arrays will soon be gone */
  50         x86_cpu_to_apicid_early_ptr = NULL;
  51         x86_bios_cpu_apicid_early_ptr = NULL;
  52 #ifdef CONFIG_NUMA
  53         x86_cpu_to_node_map_early_ptr = NULL;
  54 #endif
  55 }
  56
  57 #ifdef CONFIG_X86_32
  58 /*
  59  * Great future not-so-futuristic plan: make i386 and x86_64 do it
  60  * the same way
  61  */
  62 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
  63 EXPORT_SYMBOL(__per_cpu_offset);
  64 #endif
  65
  66 /*
  67  * Great future plan:
  68  * Declare PDA itself and support (irqstack,tss,pgd) as per cpu data.
  69  * Always point %gs to its beginning
  70  */
  71 void __init setup_per_cpu_areas(void)
  72 {
  73         int i;
  74         unsigned long size;
  75
  76 #ifdef CONFIG_HOTPLUG_CPU
  77         prefill_possible_map();
  78 #endif
  79
  80         /* Copy section for each CPU (we discard the original) */
  81         size = PERCPU_ENOUGH_ROOM;
  82         printk(KERN_INFO "PERCPU: Allocating %lu bytes of per cpu data\n",
  83                           size);
  84
  85         for_each_possible_cpu(i) {
  86                 char *ptr;
  87 #ifndef CONFIG_NEED_MULTIPLE_NODES
  88                 ptr = alloc_bootmem_pages(size);
  89 #else
  90                 int node = early_cpu_to_node(i);
  91                 if (!node_online(node) || !NODE_DATA(node)) {
  92                         ptr = alloc_bootmem_pages(size);
  93                         printk(KERN_INFO
  94                                "cpu %d has no node or node-local memory\n", i);
  95                 }
  96                 else
  97                         ptr = alloc_bootmem_pages_node(NODE_DATA(node), size);
  98 #endif
  99                 if (!ptr)
 100                         panic("Cannot allocate cpu data for CPU %d\n", i);
 101 #ifdef CONFIG_X86_64
 102                 cpu_pda(i)->data_offset = ptr - __per_cpu_start;
 103 #else
 104                 __per_cpu_offset[i] = ptr - __per_cpu_start;
 105 #endif
 106                 memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);
 107         }
 108
 109         /* Setup percpu data maps */
 110         setup_per_cpu_maps();
 111 }
 112
 113 #endif