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 #ifdef CONFIG_X86_LOCAL_APIC
  16 unsigned int num_processors;
  17 unsigned disabled_cpus __cpuinitdata;
  18 /* Processor that is doing the boot up */
  19 unsigned int boot_cpu_physical_apicid = -1U;
  20 EXPORT_SYMBOL(boot_cpu_physical_apicid);
  21
  22 DEFINE_PER_CPU(u16, x86_cpu_to_apicid) = BAD_APICID;
  23 EXPORT_PER_CPU_SYMBOL(x86_cpu_to_apicid);
  24
  25 /* Bitmask of physically existing CPUs */
  26 physid_mask_t phys_cpu_present_map;
  27 #endif
  28
  29 #if defined(CONFIG_HAVE_SETUP_PER_CPU_AREA) && defined(CONFIG_X86_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_HAVE_CPUMASK_OF_CPU_MAP
  58 cpumask_t *cpumask_of_cpu_map __read_mostly;
  59 EXPORT_SYMBOL(cpumask_of_cpu_map);
  60
  61 /* requires nr_cpu_ids to be initialized */
  62 static void __init setup_cpumask_of_cpu(void)
  63 {
  64         int i;
  65
  66         /* alloc_bootmem zeroes memory */
  67         cpumask_of_cpu_map = alloc_bootmem_low(sizeof(cpumask_t) * nr_cpu_ids);
  68         for (i = 0; i < nr_cpu_ids; i++)
  69                 cpu_set(i, cpumask_of_cpu_map[i]);
  70 }
  71 #else
  72 static inline void setup_cpumask_of_cpu(void) { }
  73 #endif
  74
  75 #ifdef CONFIG_X86_32
  76 /*
  77  * Great future not-so-futuristic plan: make i386 and x86_64 do it
  78  * the same way
  79  */
  80 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
  81 EXPORT_SYMBOL(__per_cpu_offset);
  82 #endif
  83
  84 /*
  85  * Great future plan:
  86  * Declare PDA itself and support (irqstack,tss,pgd) as per cpu data.
  87  * Always point %gs to its beginning
  88  */
  89 void __init setup_per_cpu_areas(void)
  90 {
  91         int i, highest_cpu = 0;
  92         unsigned long size;
  93
  94 #ifdef CONFIG_HOTPLUG_CPU
  95         prefill_possible_map();
  96 #endif
  97
  98         /* Copy section for each CPU (we discard the original) */
  99         size = PERCPU_ENOUGH_ROOM;
 100         printk(KERN_INFO "PERCPU: Allocating %lu bytes of per cpu data\n",
 101                           size);
 102
 103         for_each_possible_cpu(i) {
 104                 char *ptr;
 105 #ifndef CONFIG_NEED_MULTIPLE_NODES
 106                 ptr = alloc_bootmem_pages(size);
 107 #else
 108                 int node = early_cpu_to_node(i);
 109                 if (!node_online(node) || !NODE_DATA(node)) {
 110                         ptr = alloc_bootmem_pages(size);
 111                         printk(KERN_INFO
 112                                "cpu %d has no node or node-local memory\n", i);
 113                 }
 114                 else
 115                         ptr = alloc_bootmem_pages_node(NODE_DATA(node), size);
 116 #endif
 117                 if (!ptr)
 118                         panic("Cannot allocate cpu data for CPU %d\n", i);
 119 #ifdef CONFIG_X86_64
 120                 cpu_pda(i)->data_offset = ptr - __per_cpu_start;
 121 #else
 122                 __per_cpu_offset[i] = ptr - __per_cpu_start;
 123 #endif
 124                 memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);
 125
 126                 highest_cpu = i;
 127         }
 128
 129         nr_cpu_ids = highest_cpu + 1;
 130         printk(KERN_DEBUG "NR_CPUS: %d, nr_cpu_ids: %d\n", NR_CPUS, nr_cpu_ids);
 131
 132         /* Setup percpu data maps */
 133         setup_per_cpu_maps();
 134
 135         /* Setup cpumask_of_cpu map */
 136         setup_cpumask_of_cpu();
 137 }
 138
 139 #endif