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 <linux/kexec.h>
7 #include <linux/crash_dump.h>
9 #include <linux/topology.h>
10 #include <asm/sections.h>
11 #include <asm/processor.h>
12 #include <asm/setup.h>
13 #include <asm/mpspec.h>
14 #include <asm/apicdef.h>
15 #include <asm/highmem.h>
16 #include <asm/proto.h>
17 #include <asm/cpumask.h>
19 #ifdef CONFIG_DEBUG_PER_CPU_MAPS
20 # define DBG(x...) printk(KERN_DEBUG x)
25 DEFINE_PER_CPU(int, cpu_number);
26 EXPORT_PER_CPU_SYMBOL(cpu_number);
28 #ifdef CONFIG_HAVE_SETUP_PER_CPU_AREA
31 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly = {
32 [0] = (unsigned long)__per_cpu_load,
35 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
37 EXPORT_SYMBOL(__per_cpu_offset);
41 * Declare PDA itself and support (irqstack,tss,pgd) as per cpu data.
42 * Always point %gs to its beginning
44 void __init setup_per_cpu_areas(void)
50 /* Copy section for each CPU (we discard the original) */
51 size = roundup(PERCPU_ENOUGH_ROOM, PAGE_SIZE);
53 pr_info("NR_CPUS:%d nr_cpumask_bits:%d nr_cpu_ids:%d nr_node_ids:%d\n",
54 NR_CPUS, nr_cpumask_bits, nr_cpu_ids, nr_node_ids);
56 pr_info("PERCPU: Allocating %zd bytes of per cpu data\n", size);
58 for_each_possible_cpu(cpu) {
59 #ifndef CONFIG_NEED_MULTIPLE_NODES
60 ptr = alloc_bootmem_pages(size);
62 int node = early_cpu_to_node(cpu);
63 if (!node_online(node) || !NODE_DATA(node)) {
64 ptr = alloc_bootmem_pages(size);
65 pr_info("cpu %d has no node %d or node-local memory\n",
67 pr_debug("per cpu data for cpu%d at %016lx\n",
70 ptr = alloc_bootmem_pages_node(NODE_DATA(node), size);
71 pr_debug("per cpu data for cpu%d on node%d at %016lx\n",
72 cpu, node, __pa(ptr));
76 memcpy(ptr, __per_cpu_load, __per_cpu_end - __per_cpu_start);
77 per_cpu_offset(cpu) = ptr - __per_cpu_start;
78 per_cpu(this_cpu_off, cpu) = per_cpu_offset(cpu);
79 per_cpu(cpu_number, cpu) = cpu;
81 * Copy data used in early init routines from the initial arrays to the
82 * per cpu data areas. These arrays then become expendable and the
83 * *_early_ptr's are zeroed indicating that the static arrays are gone.
85 #ifdef CONFIG_X86_LOCAL_APIC
86 per_cpu(x86_cpu_to_apicid, cpu) =
87 early_per_cpu_map(x86_cpu_to_apicid, cpu);
88 per_cpu(x86_bios_cpu_apicid, cpu) =
89 early_per_cpu_map(x86_bios_cpu_apicid, cpu);
92 per_cpu(irq_stack_ptr, cpu) =
93 per_cpu(irq_stack_union.irq_stack, cpu) + IRQ_STACK_SIZE - 64;
95 per_cpu(x86_cpu_to_node_map, cpu) =
96 early_per_cpu_map(x86_cpu_to_node_map, cpu);
99 * Up to this point, CPU0 has been using .data.init
100 * area. Reload %gs offset for CPU0.
106 DBG("PERCPU: cpu %4d %p\n", cpu, ptr);
109 /* indicate the early static arrays will soon be gone */
110 early_per_cpu_ptr(x86_cpu_to_apicid) = NULL;
111 early_per_cpu_ptr(x86_bios_cpu_apicid) = NULL;
112 #if defined(CONFIG_X86_64) && defined(CONFIG_NUMA)
113 early_per_cpu_ptr(x86_cpu_to_node_map) = NULL;
116 /* Setup node to cpumask map */
117 setup_node_to_cpumask_map();
119 /* Setup cpu initialized, callin, callout masks */
120 setup_cpu_local_masks();