xref: /linux/arch/x86/kernel/setup_percpu.c (revision 7ec7fb394298c212c30e063c57e0aa895efe9439)
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 <asm/smp.h>
9 #include <asm/percpu.h>
10 #include <asm/sections.h>
11 #include <asm/processor.h>
12 #include <asm/setup.h>
13 #include <asm/topology.h>
14 #include <asm/mpspec.h>
15 #include <asm/apicdef.h>
16 #include <asm/highmem.h>
17 
18 #ifdef CONFIG_X86_LOCAL_APIC
19 unsigned int num_processors;
20 unsigned disabled_cpus __cpuinitdata;
21 /* Processor that is doing the boot up */
22 unsigned int boot_cpu_physical_apicid = -1U;
23 unsigned int max_physical_apicid;
24 EXPORT_SYMBOL(boot_cpu_physical_apicid);
25 
26 /* Bitmask of physically existing CPUs */
27 physid_mask_t phys_cpu_present_map;
28 #endif
29 
30 /* map cpu index to physical APIC ID */
31 DEFINE_EARLY_PER_CPU(u16, x86_cpu_to_apicid, BAD_APICID);
32 DEFINE_EARLY_PER_CPU(u16, x86_bios_cpu_apicid, BAD_APICID);
33 EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_apicid);
34 EXPORT_EARLY_PER_CPU_SYMBOL(x86_bios_cpu_apicid);
35 
36 #if defined(CONFIG_NUMA) && defined(CONFIG_X86_64)
37 #define	X86_64_NUMA	1
38 
39 /* map cpu index to node index */
40 DEFINE_EARLY_PER_CPU(int, x86_cpu_to_node_map, NUMA_NO_NODE);
41 EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_node_map);
42 
43 /* which logical CPUs are on which nodes */
44 cpumask_t *node_to_cpumask_map;
45 EXPORT_SYMBOL(node_to_cpumask_map);
46 
47 /* setup node_to_cpumask_map */
48 static void __init setup_node_to_cpumask_map(void);
49 
50 #else
51 static inline void setup_node_to_cpumask_map(void) { }
52 #endif
53 
54 #if defined(CONFIG_HAVE_SETUP_PER_CPU_AREA) && defined(CONFIG_X86_SMP)
55 /*
56  * Copy data used in early init routines from the initial arrays to the
57  * per cpu data areas.  These arrays then become expendable and the
58  * *_early_ptr's are zeroed indicating that the static arrays are gone.
59  */
60 static void __init setup_per_cpu_maps(void)
61 {
62 	int cpu;
63 
64 	for_each_possible_cpu(cpu) {
65 		per_cpu(x86_cpu_to_apicid, cpu) =
66 				early_per_cpu_map(x86_cpu_to_apicid, cpu);
67 		per_cpu(x86_bios_cpu_apicid, cpu) =
68 				early_per_cpu_map(x86_bios_cpu_apicid, cpu);
69 #ifdef X86_64_NUMA
70 		per_cpu(x86_cpu_to_node_map, cpu) =
71 				early_per_cpu_map(x86_cpu_to_node_map, cpu);
72 #endif
73 	}
74 
75 	/* indicate the early static arrays will soon be gone */
76 	early_per_cpu_ptr(x86_cpu_to_apicid) = NULL;
77 	early_per_cpu_ptr(x86_bios_cpu_apicid) = NULL;
78 #ifdef X86_64_NUMA
79 	early_per_cpu_ptr(x86_cpu_to_node_map) = NULL;
80 #endif
81 }
82 
83 #ifdef CONFIG_X86_32
84 /*
85  * Great future not-so-futuristic plan: make i386 and x86_64 do it
86  * the same way
87  */
88 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
89 EXPORT_SYMBOL(__per_cpu_offset);
90 static inline void setup_cpu_pda_map(void) { }
91 
92 #elif !defined(CONFIG_SMP)
93 static inline void setup_cpu_pda_map(void) { }
94 
95 #else /* CONFIG_SMP && CONFIG_X86_64 */
96 
97 /*
98  * Allocate cpu_pda pointer table and array via alloc_bootmem.
99  */
100 static void __init setup_cpu_pda_map(void)
101 {
102 	char *pda;
103 	struct x8664_pda **new_cpu_pda;
104 	unsigned long size;
105 	int cpu;
106 
107 	size = roundup(sizeof(struct x8664_pda), cache_line_size());
108 
109 	/* allocate cpu_pda array and pointer table */
110 	{
111 		unsigned long tsize = nr_cpu_ids * sizeof(void *);
112 		unsigned long asize = size * (nr_cpu_ids - 1);
113 
114 		tsize = roundup(tsize, cache_line_size());
115 		new_cpu_pda = alloc_bootmem(tsize + asize);
116 		pda = (char *)new_cpu_pda + tsize;
117 	}
118 
119 	/* initialize pointer table to static pda's */
120 	for_each_possible_cpu(cpu) {
121 		if (cpu == 0) {
122 			/* leave boot cpu pda in place */
123 			new_cpu_pda[0] = cpu_pda(0);
124 			continue;
125 		}
126 		new_cpu_pda[cpu] = (struct x8664_pda *)pda;
127 		new_cpu_pda[cpu]->in_bootmem = 1;
128 		pda += size;
129 	}
130 
131 	/* point to new pointer table */
132 	_cpu_pda = new_cpu_pda;
133 }
134 #endif
135 
136 /*
137  * Great future plan:
138  * Declare PDA itself and support (irqstack,tss,pgd) as per cpu data.
139  * Always point %gs to its beginning
140  */
141 void __init setup_per_cpu_areas(void)
142 {
143 	ssize_t size, old_size;
144 	char *ptr;
145 	int cpu;
146 	unsigned long align = 1;
147 
148 	/* Setup cpu_pda map */
149 	setup_cpu_pda_map();
150 
151 	/* Copy section for each CPU (we discard the original) */
152 	old_size = PERCPU_ENOUGH_ROOM;
153 	align = max_t(unsigned long, PAGE_SIZE, align);
154 	size = roundup(old_size, align);
155 
156 	pr_info("NR_CPUS:%d nr_cpumask_bits:%d nr_cpu_ids:%d nr_node_ids:%d\n",
157 		NR_CPUS, nr_cpumask_bits, nr_cpu_ids, nr_node_ids);
158 
159 	pr_info("PERCPU: Allocating %zd bytes of per cpu data\n", size);
160 
161 	for_each_possible_cpu(cpu) {
162 #ifndef CONFIG_NEED_MULTIPLE_NODES
163 		ptr = __alloc_bootmem(size, align,
164 				 __pa(MAX_DMA_ADDRESS));
165 #else
166 		int node = early_cpu_to_node(cpu);
167 		if (!node_online(node) || !NODE_DATA(node)) {
168 			ptr = __alloc_bootmem(size, align,
169 					 __pa(MAX_DMA_ADDRESS));
170 			pr_info("cpu %d has no node %d or node-local memory\n",
171 				cpu, node);
172 			pr_debug("per cpu data for cpu%d at %016lx\n",
173 				 cpu, __pa(ptr));
174 		} else {
175 			ptr = __alloc_bootmem_node(NODE_DATA(node), size, align,
176 							__pa(MAX_DMA_ADDRESS));
177 			pr_debug("per cpu data for cpu%d on node%d at %016lx\n",
178 				cpu, node, __pa(ptr));
179 		}
180 #endif
181 		per_cpu_offset(cpu) = ptr - __per_cpu_start;
182 		memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);
183 	}
184 
185 	/* Setup percpu data maps */
186 	setup_per_cpu_maps();
187 
188 	/* Setup node to cpumask map */
189 	setup_node_to_cpumask_map();
190 }
191 
192 #endif
193 
194 #ifdef X86_64_NUMA
195 
196 /*
197  * Allocate node_to_cpumask_map based on number of available nodes
198  * Requires node_possible_map to be valid.
199  *
200  * Note: node_to_cpumask() is not valid until after this is done.
201  */
202 static void __init setup_node_to_cpumask_map(void)
203 {
204 	unsigned int node, num = 0;
205 	cpumask_t *map;
206 
207 	/* setup nr_node_ids if not done yet */
208 	if (nr_node_ids == MAX_NUMNODES) {
209 		for_each_node_mask(node, node_possible_map)
210 			num = node;
211 		nr_node_ids = num + 1;
212 	}
213 
214 	/* allocate the map */
215 	map = alloc_bootmem_low(nr_node_ids * sizeof(cpumask_t));
216 
217 	pr_debug("Node to cpumask map at %p for %d nodes\n",
218 		 map, nr_node_ids);
219 
220 	/* node_to_cpumask() will now work */
221 	node_to_cpumask_map = map;
222 }
223 
224 void __cpuinit numa_set_node(int cpu, int node)
225 {
226 	int *cpu_to_node_map = early_per_cpu_ptr(x86_cpu_to_node_map);
227 
228 	if (cpu_pda(cpu) && node != NUMA_NO_NODE)
229 		cpu_pda(cpu)->nodenumber = node;
230 
231 	if (cpu_to_node_map)
232 		cpu_to_node_map[cpu] = node;
233 
234 	else if (per_cpu_offset(cpu))
235 		per_cpu(x86_cpu_to_node_map, cpu) = node;
236 
237 	else
238 		pr_debug("Setting node for non-present cpu %d\n", cpu);
239 }
240 
241 void __cpuinit numa_clear_node(int cpu)
242 {
243 	numa_set_node(cpu, NUMA_NO_NODE);
244 }
245 
246 #ifndef CONFIG_DEBUG_PER_CPU_MAPS
247 
248 void __cpuinit numa_add_cpu(int cpu)
249 {
250 	cpu_set(cpu, node_to_cpumask_map[early_cpu_to_node(cpu)]);
251 }
252 
253 void __cpuinit numa_remove_cpu(int cpu)
254 {
255 	cpu_clear(cpu, node_to_cpumask_map[cpu_to_node(cpu)]);
256 }
257 
258 #else /* CONFIG_DEBUG_PER_CPU_MAPS */
259 
260 /*
261  * --------- debug versions of the numa functions ---------
262  */
263 static void __cpuinit numa_set_cpumask(int cpu, int enable)
264 {
265 	int node = cpu_to_node(cpu);
266 	cpumask_t *mask;
267 	char buf[64];
268 
269 	if (node_to_cpumask_map == NULL) {
270 		printk(KERN_ERR "node_to_cpumask_map NULL\n");
271 		dump_stack();
272 		return;
273 	}
274 
275 	mask = &node_to_cpumask_map[node];
276 	if (enable)
277 		cpu_set(cpu, *mask);
278 	else
279 		cpu_clear(cpu, *mask);
280 
281 	cpulist_scnprintf(buf, sizeof(buf), mask);
282 	printk(KERN_DEBUG "%s cpu %d node %d: mask now %s\n",
283 		enable? "numa_add_cpu":"numa_remove_cpu", cpu, node, buf);
284  }
285 
286 void __cpuinit numa_add_cpu(int cpu)
287 {
288 	numa_set_cpumask(cpu, 1);
289 }
290 
291 void __cpuinit numa_remove_cpu(int cpu)
292 {
293 	numa_set_cpumask(cpu, 0);
294 }
295 
296 int cpu_to_node(int cpu)
297 {
298 	if (early_per_cpu_ptr(x86_cpu_to_node_map)) {
299 		printk(KERN_WARNING
300 			"cpu_to_node(%d): usage too early!\n", cpu);
301 		dump_stack();
302 		return early_per_cpu_ptr(x86_cpu_to_node_map)[cpu];
303 	}
304 	return per_cpu(x86_cpu_to_node_map, cpu);
305 }
306 EXPORT_SYMBOL(cpu_to_node);
307 
308 /*
309  * Same function as cpu_to_node() but used if called before the
310  * per_cpu areas are setup.
311  */
312 int early_cpu_to_node(int cpu)
313 {
314 	if (early_per_cpu_ptr(x86_cpu_to_node_map))
315 		return early_per_cpu_ptr(x86_cpu_to_node_map)[cpu];
316 
317 	if (!per_cpu_offset(cpu)) {
318 		printk(KERN_WARNING
319 			"early_cpu_to_node(%d): no per_cpu area!\n", cpu);
320 		dump_stack();
321 		return NUMA_NO_NODE;
322 	}
323 	return per_cpu(x86_cpu_to_node_map, cpu);
324 }
325 
326 
327 /* empty cpumask */
328 static const cpumask_t cpu_mask_none;
329 
330 /*
331  * Returns a pointer to the bitmask of CPUs on Node 'node'.
332  */
333 const cpumask_t *cpumask_of_node(int node)
334 {
335 	if (node_to_cpumask_map == NULL) {
336 		printk(KERN_WARNING
337 			"cpumask_of_node(%d): no node_to_cpumask_map!\n",
338 			node);
339 		dump_stack();
340 		return (const cpumask_t *)&cpu_online_map;
341 	}
342 	if (node >= nr_node_ids) {
343 		printk(KERN_WARNING
344 			"cpumask_of_node(%d): node > nr_node_ids(%d)\n",
345 			node, nr_node_ids);
346 		dump_stack();
347 		return &cpu_mask_none;
348 	}
349 	return &node_to_cpumask_map[node];
350 }
351 EXPORT_SYMBOL(cpumask_of_node);
352 
353 /*
354  * Returns a bitmask of CPUs on Node 'node'.
355  *
356  * Side note: this function creates the returned cpumask on the stack
357  * so with a high NR_CPUS count, excessive stack space is used.  The
358  * node_to_cpumask_ptr function should be used whenever possible.
359  */
360 cpumask_t node_to_cpumask(int node)
361 {
362 	if (node_to_cpumask_map == NULL) {
363 		printk(KERN_WARNING
364 			"node_to_cpumask(%d): no node_to_cpumask_map!\n", node);
365 		dump_stack();
366 		return cpu_online_map;
367 	}
368 	if (node >= nr_node_ids) {
369 		printk(KERN_WARNING
370 			"node_to_cpumask(%d): node > nr_node_ids(%d)\n",
371 			node, nr_node_ids);
372 		dump_stack();
373 		return cpu_mask_none;
374 	}
375 	return node_to_cpumask_map[node];
376 }
377 EXPORT_SYMBOL(node_to_cpumask);
378 
379 /*
380  * --------- end of debug versions of the numa functions ---------
381  */
382 
383 #endif /* CONFIG_DEBUG_PER_CPU_MAPS */
384 
385 #endif /* X86_64_NUMA */
386 
387