1#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
2
3#include <linux/kernel.h>
4#include <linux/module.h>
5#include <linux/init.h>
6#include <linux/bootmem.h>
7#include <linux/percpu.h>
8#include <linux/kexec.h>
9#include <linux/crash_dump.h>
10#include <linux/smp.h>
11#include <linux/topology.h>
12#include <linux/pfn.h>
13#include <asm/sections.h>
14#include <asm/processor.h>
15#include <asm/setup.h>
16#include <asm/mpspec.h>
17#include <asm/apicdef.h>
18#include <asm/highmem.h>
19#include <asm/proto.h>
20#include <asm/cpumask.h>
21#include <asm/cpu.h>
22#include <asm/stackprotector.h>
23
24DEFINE_PER_CPU_READ_MOSTLY(int, cpu_number);
25EXPORT_PER_CPU_SYMBOL(cpu_number);
26
27#ifdef CONFIG_X86_64
28#define BOOT_PERCPU_OFFSET ((unsigned long)__per_cpu_load)
29#else
30#define BOOT_PERCPU_OFFSET 0
31#endif
32
33DEFINE_PER_CPU(unsigned long, this_cpu_off) = BOOT_PERCPU_OFFSET;
34EXPORT_PER_CPU_SYMBOL(this_cpu_off);
35
36unsigned long __per_cpu_offset[NR_CPUS] __read_mostly = {
37 [0 ... NR_CPUS-1] = BOOT_PERCPU_OFFSET,
38};
39EXPORT_SYMBOL(__per_cpu_offset);
40
41
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43
44
45
46
47
48#ifdef CONFIG_X86_64
49#define PERCPU_FIRST_CHUNK_RESERVE PERCPU_MODULE_RESERVE
50#else
51#define PERCPU_FIRST_CHUNK_RESERVE 0
52#endif
53
54#ifdef CONFIG_X86_32
55
56
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58
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62
63
64
65static bool __init pcpu_need_numa(void)
66{
67#ifdef CONFIG_NEED_MULTIPLE_NODES
68 pg_data_t *last = NULL;
69 unsigned int cpu;
70
71 for_each_possible_cpu(cpu) {
72 int node = early_cpu_to_node(cpu);
73
74 if (node_online(node) && NODE_DATA(node) &&
75 last && last != NODE_DATA(node))
76 return true;
77
78 last = NODE_DATA(node);
79 }
80#endif
81 return false;
82}
83#endif
84
85
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95
96
97
98static void * __init pcpu_alloc_bootmem(unsigned int cpu, unsigned long size,
99 unsigned long align)
100{
101 const unsigned long goal = __pa(MAX_DMA_ADDRESS);
102#ifdef CONFIG_NEED_MULTIPLE_NODES
103 int node = early_cpu_to_node(cpu);
104 void *ptr;
105
106 if (!node_online(node) || !NODE_DATA(node)) {
107 ptr = __alloc_bootmem_nopanic(size, align, goal);
108 pr_info("cpu %d has no node %d or node-local memory\n",
109 cpu, node);
110 pr_debug("per cpu data for cpu%d %lu bytes at %016lx\n",
111 cpu, size, __pa(ptr));
112 } else {
113 ptr = __alloc_bootmem_node_nopanic(NODE_DATA(node),
114 size, align, goal);
115 pr_debug("per cpu data for cpu%d %lu bytes on node%d at %016lx\n",
116 cpu, size, node, __pa(ptr));
117 }
118 return ptr;
119#else
120 return __alloc_bootmem_nopanic(size, align, goal);
121#endif
122}
123
124
125
126
127static void * __init pcpu_fc_alloc(unsigned int cpu, size_t size, size_t align)
128{
129 return pcpu_alloc_bootmem(cpu, size, align);
130}
131
132static void __init pcpu_fc_free(void *ptr, size_t size)
133{
134 free_bootmem(__pa(ptr), size);
135}
136
137static int __init pcpu_cpu_distance(unsigned int from, unsigned int to)
138{
139#ifdef CONFIG_NEED_MULTIPLE_NODES
140 if (early_cpu_to_node(from) == early_cpu_to_node(to))
141 return LOCAL_DISTANCE;
142 else
143 return REMOTE_DISTANCE;
144#else
145 return LOCAL_DISTANCE;
146#endif
147}
148
149static void __init pcpup_populate_pte(unsigned long addr)
150{
151 populate_extra_pte(addr);
152}
153
154static inline void setup_percpu_segment(int cpu)
155{
156#ifdef CONFIG_X86_32
157 struct desc_struct gdt;
158
159 pack_descriptor(&gdt, per_cpu_offset(cpu), 0xFFFFF,
160 0x2 | DESCTYPE_S, 0x8);
161 gdt.s = 1;
162 write_gdt_entry(get_cpu_gdt_table(cpu),
163 GDT_ENTRY_PERCPU, &gdt, DESCTYPE_S);
164#endif
165}
166
167void __init setup_per_cpu_areas(void)
168{
169 unsigned int cpu;
170 unsigned long delta;
171 int rc;
172
173 pr_info("NR_CPUS:%d nr_cpumask_bits:%d nr_cpu_ids:%d nr_node_ids:%d\n",
174 NR_CPUS, nr_cpumask_bits, nr_cpu_ids, nr_node_ids);
175
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180
181
182#ifdef CONFIG_X86_32
183 if (pcpu_chosen_fc == PCPU_FC_AUTO && pcpu_need_numa())
184 pcpu_chosen_fc = PCPU_FC_PAGE;
185#endif
186 rc = -EINVAL;
187 if (pcpu_chosen_fc != PCPU_FC_PAGE) {
188 const size_t dyn_size = PERCPU_MODULE_RESERVE +
189 PERCPU_DYNAMIC_RESERVE - PERCPU_FIRST_CHUNK_RESERVE;
190 size_t atom_size;
191
192
193
194
195
196
197
198
199#ifdef CONFIG_X86_64
200 atom_size = PMD_SIZE;
201#else
202 atom_size = PAGE_SIZE;
203#endif
204 rc = pcpu_embed_first_chunk(PERCPU_FIRST_CHUNK_RESERVE,
205 dyn_size, atom_size,
206 pcpu_cpu_distance,
207 pcpu_fc_alloc, pcpu_fc_free);
208 if (rc < 0)
209 pr_warning("%s allocator failed (%d), falling back to page size\n",
210 pcpu_fc_names[pcpu_chosen_fc], rc);
211 }
212 if (rc < 0)
213 rc = pcpu_page_first_chunk(PERCPU_FIRST_CHUNK_RESERVE,
214 pcpu_fc_alloc, pcpu_fc_free,
215 pcpup_populate_pte);
216 if (rc < 0)
217 panic("cannot initialize percpu area (err=%d)", rc);
218
219
220 delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
221 for_each_possible_cpu(cpu) {
222 per_cpu_offset(cpu) = delta + pcpu_unit_offsets[cpu];
223 per_cpu(this_cpu_off, cpu) = per_cpu_offset(cpu);
224 per_cpu(cpu_number, cpu) = cpu;
225 setup_percpu_segment(cpu);
226 setup_stack_canary_segment(cpu);
227
228
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232
233
234#ifdef CONFIG_X86_LOCAL_APIC
235 per_cpu(x86_cpu_to_apicid, cpu) =
236 early_per_cpu_map(x86_cpu_to_apicid, cpu);
237 per_cpu(x86_bios_cpu_apicid, cpu) =
238 early_per_cpu_map(x86_bios_cpu_apicid, cpu);
239 per_cpu(x86_cpu_to_acpiid, cpu) =
240 early_per_cpu_map(x86_cpu_to_acpiid, cpu);
241#endif
242#ifdef CONFIG_X86_32
243 per_cpu(x86_cpu_to_logical_apicid, cpu) =
244 early_per_cpu_map(x86_cpu_to_logical_apicid, cpu);
245#endif
246#ifdef CONFIG_X86_64
247 per_cpu(irq_stack_ptr, cpu) =
248 per_cpu(irq_stack_union.irq_stack, cpu) +
249 IRQ_STACK_SIZE - 64;
250#endif
251#ifdef CONFIG_NUMA
252 per_cpu(x86_cpu_to_node_map, cpu) =
253 early_per_cpu_map(x86_cpu_to_node_map, cpu);
254
255
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259
260
261
262 set_cpu_numa_node(cpu, early_cpu_to_node(cpu));
263#endif
264
265
266
267
268 if (!cpu)
269 switch_to_new_gdt(cpu);
270 }
271
272
273#ifdef CONFIG_X86_LOCAL_APIC
274 early_per_cpu_ptr(x86_cpu_to_apicid) = NULL;
275 early_per_cpu_ptr(x86_bios_cpu_apicid) = NULL;
276 early_per_cpu_ptr(x86_cpu_to_acpiid) = NULL;
277#endif
278#ifdef CONFIG_X86_32
279 early_per_cpu_ptr(x86_cpu_to_logical_apicid) = NULL;
280#endif
281#ifdef CONFIG_NUMA
282 early_per_cpu_ptr(x86_cpu_to_node_map) = NULL;
283#endif
284
285
286 setup_node_to_cpumask_map();
287
288
289 setup_cpu_local_masks();
290}
291