x86: pass in cpu number to switch_to_new_gdt()
[linux-3.10.git] / arch / x86 / kernel / setup_percpu.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 <linux/kexec.h>
7 #include <linux/crash_dump.h>
8 #include <linux/smp.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>
18 #include <asm/cpu.h>
19
20 #ifdef CONFIG_DEBUG_PER_CPU_MAPS
21 # define DBG(x...) printk(KERN_DEBUG x)
22 #else
23 # define DBG(x...)
24 #endif
25
26 DEFINE_PER_CPU(int, cpu_number);
27 EXPORT_PER_CPU_SYMBOL(cpu_number);
28
29 #ifdef CONFIG_X86_64
30 #define BOOT_PERCPU_OFFSET ((unsigned long)__per_cpu_load)
31 #else
32 #define BOOT_PERCPU_OFFSET 0
33 #endif
34
35 DEFINE_PER_CPU(unsigned long, this_cpu_off) = BOOT_PERCPU_OFFSET;
36 EXPORT_PER_CPU_SYMBOL(this_cpu_off);
37
38 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly = {
39         [0 ... NR_CPUS-1] = BOOT_PERCPU_OFFSET,
40 };
41 EXPORT_SYMBOL(__per_cpu_offset);
42
43 static inline void setup_percpu_segment(int cpu)
44 {
45 #ifdef CONFIG_X86_32
46         struct desc_struct gdt;
47
48         pack_descriptor(&gdt, per_cpu_offset(cpu), 0xFFFFF,
49                         0x2 | DESCTYPE_S, 0x8);
50         gdt.s = 1;
51         write_gdt_entry(get_cpu_gdt_table(cpu),
52                         GDT_ENTRY_PERCPU, &gdt, DESCTYPE_S);
53 #endif
54 }
55
56 /*
57  * Great future plan:
58  * Declare PDA itself and support (irqstack,tss,pgd) as per cpu data.
59  * Always point %gs to its beginning
60  */
61 void __init setup_per_cpu_areas(void)
62 {
63         ssize_t size;
64         char *ptr;
65         int cpu;
66
67         /* Copy section for each CPU (we discard the original) */
68         size = roundup(PERCPU_ENOUGH_ROOM, PAGE_SIZE);
69
70         pr_info("NR_CPUS:%d nr_cpumask_bits:%d nr_cpu_ids:%d nr_node_ids:%d\n",
71                 NR_CPUS, nr_cpumask_bits, nr_cpu_ids, nr_node_ids);
72
73         pr_info("PERCPU: Allocating %zd bytes of per cpu data\n", size);
74
75         for_each_possible_cpu(cpu) {
76 #ifndef CONFIG_NEED_MULTIPLE_NODES
77                 ptr = alloc_bootmem_pages(size);
78 #else
79                 int node = early_cpu_to_node(cpu);
80                 if (!node_online(node) || !NODE_DATA(node)) {
81                         ptr = alloc_bootmem_pages(size);
82                         pr_info("cpu %d has no node %d or node-local memory\n",
83                                 cpu, node);
84                         pr_debug("per cpu data for cpu%d at %016lx\n",
85                                  cpu, __pa(ptr));
86                 } else {
87                         ptr = alloc_bootmem_pages_node(NODE_DATA(node), size);
88                         pr_debug("per cpu data for cpu%d on node%d at %016lx\n",
89                                 cpu, node, __pa(ptr));
90                 }
91 #endif
92
93                 memcpy(ptr, __per_cpu_load, __per_cpu_end - __per_cpu_start);
94                 per_cpu_offset(cpu) = ptr - __per_cpu_start;
95                 per_cpu(this_cpu_off, cpu) = per_cpu_offset(cpu);
96                 per_cpu(cpu_number, cpu) = cpu;
97                 setup_percpu_segment(cpu);
98                 /*
99                  * Copy data used in early init routines from the
100                  * initial arrays to the per cpu data areas.  These
101                  * arrays then become expendable and the *_early_ptr's
102                  * are zeroed indicating that the static arrays are
103                  * gone.
104                  */
105 #ifdef CONFIG_X86_LOCAL_APIC
106                 per_cpu(x86_cpu_to_apicid, cpu) =
107                         early_per_cpu_map(x86_cpu_to_apicid, cpu);
108                 per_cpu(x86_bios_cpu_apicid, cpu) =
109                         early_per_cpu_map(x86_bios_cpu_apicid, cpu);
110 #endif
111 #ifdef CONFIG_X86_64
112                 per_cpu(irq_stack_ptr, cpu) =
113                         per_cpu(irq_stack_union.irq_stack, cpu) +
114                         IRQ_STACK_SIZE - 64;
115 #ifdef CONFIG_NUMA
116                 per_cpu(x86_cpu_to_node_map, cpu) =
117                         early_per_cpu_map(x86_cpu_to_node_map, cpu);
118 #endif
119 #endif
120                 /*
121                  * Up to this point, the boot CPU has been using .data.init
122                  * area.  Reload any changed state for the boot CPU.
123                  */
124                 if (cpu == boot_cpu_id)
125                         switch_to_new_gdt(cpu);
126
127                 DBG("PERCPU: cpu %4d %p\n", cpu, ptr);
128         }
129
130         /* indicate the early static arrays will soon be gone */
131 #ifdef CONFIG_X86_LOCAL_APIC
132         early_per_cpu_ptr(x86_cpu_to_apicid) = NULL;
133         early_per_cpu_ptr(x86_bios_cpu_apicid) = NULL;
134 #endif
135 #if defined(CONFIG_X86_64) && defined(CONFIG_NUMA)
136         early_per_cpu_ptr(x86_cpu_to_node_map) = NULL;
137 #endif
138
139         /* Setup node to cpumask map */
140         setup_node_to_cpumask_map();
141
142         /* Setup cpu initialized, callin, callout masks */
143         setup_cpu_local_masks();
144 }