xref: /openbmc/linux/drivers/base/arch_numa.c (revision a1117495)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * NUMA support, based on the x86 implementation.
4  *
5  * Copyright (C) 2015 Cavium Inc.
6  * Author: Ganapatrao Kulkarni <gkulkarni@cavium.com>
7  */
8 
9 #define pr_fmt(fmt) "NUMA: " fmt
10 
11 #include <linux/acpi.h>
12 #include <linux/memblock.h>
13 #include <linux/module.h>
14 #include <linux/of.h>
15 
16 #include <asm/sections.h>
17 #include <asm/pgalloc.h>
18 
19 struct pglist_data *node_data[MAX_NUMNODES] __read_mostly;
20 EXPORT_SYMBOL(node_data);
21 nodemask_t numa_nodes_parsed __initdata;
22 static int cpu_to_node_map[NR_CPUS] = { [0 ... NR_CPUS-1] = NUMA_NO_NODE };
23 
24 static int numa_distance_cnt;
25 static u8 *numa_distance;
26 bool numa_off;
27 
28 static __init int numa_parse_early_param(char *opt)
29 {
30 	if (!opt)
31 		return -EINVAL;
32 	if (str_has_prefix(opt, "off"))
33 		numa_off = true;
34 
35 	return 0;
36 }
37 early_param("numa", numa_parse_early_param);
38 
39 cpumask_var_t node_to_cpumask_map[MAX_NUMNODES];
40 EXPORT_SYMBOL(node_to_cpumask_map);
41 
42 #ifdef CONFIG_DEBUG_PER_CPU_MAPS
43 
44 /*
45  * Returns a pointer to the bitmask of CPUs on Node 'node'.
46  */
47 const struct cpumask *cpumask_of_node(int node)
48 {
49 
50 	if (node == NUMA_NO_NODE)
51 		return cpu_all_mask;
52 
53 	if (WARN_ON(node < 0 || node >= nr_node_ids))
54 		return cpu_none_mask;
55 
56 	if (WARN_ON(node_to_cpumask_map[node] == NULL))
57 		return cpu_online_mask;
58 
59 	return node_to_cpumask_map[node];
60 }
61 EXPORT_SYMBOL(cpumask_of_node);
62 
63 #endif
64 
65 static void numa_update_cpu(unsigned int cpu, bool remove)
66 {
67 	int nid = cpu_to_node(cpu);
68 
69 	if (nid == NUMA_NO_NODE)
70 		return;
71 
72 	if (remove)
73 		cpumask_clear_cpu(cpu, node_to_cpumask_map[nid]);
74 	else
75 		cpumask_set_cpu(cpu, node_to_cpumask_map[nid]);
76 }
77 
78 void numa_add_cpu(unsigned int cpu)
79 {
80 	numa_update_cpu(cpu, false);
81 }
82 
83 void numa_remove_cpu(unsigned int cpu)
84 {
85 	numa_update_cpu(cpu, true);
86 }
87 
88 void numa_clear_node(unsigned int cpu)
89 {
90 	numa_remove_cpu(cpu);
91 	set_cpu_numa_node(cpu, NUMA_NO_NODE);
92 }
93 
94 /*
95  * Allocate node_to_cpumask_map based on number of available nodes
96  * Requires node_possible_map to be valid.
97  *
98  * Note: cpumask_of_node() is not valid until after this is done.
99  * (Use CONFIG_DEBUG_PER_CPU_MAPS to check this.)
100  */
101 static void __init setup_node_to_cpumask_map(void)
102 {
103 	int node;
104 
105 	/* setup nr_node_ids if not done yet */
106 	if (nr_node_ids == MAX_NUMNODES)
107 		setup_nr_node_ids();
108 
109 	/* allocate and clear the mapping */
110 	for (node = 0; node < nr_node_ids; node++) {
111 		alloc_bootmem_cpumask_var(&node_to_cpumask_map[node]);
112 		cpumask_clear(node_to_cpumask_map[node]);
113 	}
114 
115 	/* cpumask_of_node() will now work */
116 	pr_debug("Node to cpumask map for %u nodes\n", nr_node_ids);
117 }
118 
119 /*
120  * Set the cpu to node and mem mapping
121  */
122 void numa_store_cpu_info(unsigned int cpu)
123 {
124 	set_cpu_numa_node(cpu, cpu_to_node_map[cpu]);
125 }
126 
127 void __init early_map_cpu_to_node(unsigned int cpu, int nid)
128 {
129 	/* fallback to node 0 */
130 	if (nid < 0 || nid >= MAX_NUMNODES || numa_off)
131 		nid = 0;
132 
133 	cpu_to_node_map[cpu] = nid;
134 
135 	/*
136 	 * We should set the numa node of cpu0 as soon as possible, because it
137 	 * has already been set up online before. cpu_to_node(0) will soon be
138 	 * called.
139 	 */
140 	if (!cpu)
141 		set_cpu_numa_node(cpu, nid);
142 }
143 
144 #ifdef CONFIG_HAVE_SETUP_PER_CPU_AREA
145 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
146 EXPORT_SYMBOL(__per_cpu_offset);
147 
148 static int __init early_cpu_to_node(int cpu)
149 {
150 	return cpu_to_node_map[cpu];
151 }
152 
153 static int __init pcpu_cpu_distance(unsigned int from, unsigned int to)
154 {
155 	return node_distance(early_cpu_to_node(from), early_cpu_to_node(to));
156 }
157 
158 static void * __init pcpu_fc_alloc(unsigned int cpu, size_t size,
159 				       size_t align)
160 {
161 	int nid = early_cpu_to_node(cpu);
162 
163 	return  memblock_alloc_try_nid(size, align,
164 			__pa(MAX_DMA_ADDRESS), MEMBLOCK_ALLOC_ACCESSIBLE, nid);
165 }
166 
167 static void __init pcpu_fc_free(void *ptr, size_t size)
168 {
169 	memblock_free(ptr, size);
170 }
171 
172 #ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
173 static void __init pcpu_populate_pte(unsigned long addr)
174 {
175 	pgd_t *pgd = pgd_offset_k(addr);
176 	p4d_t *p4d;
177 	pud_t *pud;
178 	pmd_t *pmd;
179 
180 	p4d = p4d_offset(pgd, addr);
181 	if (p4d_none(*p4d)) {
182 		pud_t *new;
183 
184 		new = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
185 		if (!new)
186 			goto err_alloc;
187 		p4d_populate(&init_mm, p4d, new);
188 	}
189 
190 	pud = pud_offset(p4d, addr);
191 	if (pud_none(*pud)) {
192 		pmd_t *new;
193 
194 		new = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
195 		if (!new)
196 			goto err_alloc;
197 		pud_populate(&init_mm, pud, new);
198 	}
199 
200 	pmd = pmd_offset(pud, addr);
201 	if (!pmd_present(*pmd)) {
202 		pte_t *new;
203 
204 		new = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
205 		if (!new)
206 			goto err_alloc;
207 		pmd_populate_kernel(&init_mm, pmd, new);
208 	}
209 
210 	return;
211 
212 err_alloc:
213 	panic("%s: Failed to allocate %lu bytes align=%lx from=%lx\n",
214 	      __func__, PAGE_SIZE, PAGE_SIZE, PAGE_SIZE);
215 }
216 #endif
217 
218 void __init setup_per_cpu_areas(void)
219 {
220 	unsigned long delta;
221 	unsigned int cpu;
222 	int rc = -EINVAL;
223 
224 	if (pcpu_chosen_fc != PCPU_FC_PAGE) {
225 		/*
226 		 * Always reserve area for module percpu variables.  That's
227 		 * what the legacy allocator did.
228 		 */
229 		rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE,
230 					    PERCPU_DYNAMIC_RESERVE, PAGE_SIZE,
231 					    pcpu_cpu_distance,
232 					    pcpu_fc_alloc, pcpu_fc_free);
233 #ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
234 		if (rc < 0)
235 			pr_warn("PERCPU: %s allocator failed (%d), falling back to page size\n",
236 				   pcpu_fc_names[pcpu_chosen_fc], rc);
237 #endif
238 	}
239 
240 #ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
241 	if (rc < 0)
242 		rc = pcpu_page_first_chunk(PERCPU_MODULE_RESERVE,
243 					   pcpu_fc_alloc,
244 					   pcpu_fc_free,
245 					   pcpu_populate_pte);
246 #endif
247 	if (rc < 0)
248 		panic("Failed to initialize percpu areas (err=%d).", rc);
249 
250 	delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
251 	for_each_possible_cpu(cpu)
252 		__per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];
253 }
254 #endif
255 
256 /**
257  * numa_add_memblk() - Set node id to memblk
258  * @nid: NUMA node ID of the new memblk
259  * @start: Start address of the new memblk
260  * @end:  End address of the new memblk
261  *
262  * RETURNS:
263  * 0 on success, -errno on failure.
264  */
265 int __init numa_add_memblk(int nid, u64 start, u64 end)
266 {
267 	int ret;
268 
269 	ret = memblock_set_node(start, (end - start), &memblock.memory, nid);
270 	if (ret < 0) {
271 		pr_err("memblock [0x%llx - 0x%llx] failed to add on node %d\n",
272 			start, (end - 1), nid);
273 		return ret;
274 	}
275 
276 	node_set(nid, numa_nodes_parsed);
277 	return ret;
278 }
279 
280 /*
281  * Initialize NODE_DATA for a node on the local memory
282  */
283 static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn)
284 {
285 	const size_t nd_size = roundup(sizeof(pg_data_t), SMP_CACHE_BYTES);
286 	u64 nd_pa;
287 	void *nd;
288 	int tnid;
289 
290 	if (start_pfn >= end_pfn)
291 		pr_info("Initmem setup node %d [<memory-less node>]\n", nid);
292 
293 	nd_pa = memblock_phys_alloc_try_nid(nd_size, SMP_CACHE_BYTES, nid);
294 	if (!nd_pa)
295 		panic("Cannot allocate %zu bytes for node %d data\n",
296 		      nd_size, nid);
297 
298 	nd = __va(nd_pa);
299 
300 	/* report and initialize */
301 	pr_info("NODE_DATA [mem %#010Lx-%#010Lx]\n",
302 		nd_pa, nd_pa + nd_size - 1);
303 	tnid = early_pfn_to_nid(nd_pa >> PAGE_SHIFT);
304 	if (tnid != nid)
305 		pr_info("NODE_DATA(%d) on node %d\n", nid, tnid);
306 
307 	node_data[nid] = nd;
308 	memset(NODE_DATA(nid), 0, sizeof(pg_data_t));
309 	NODE_DATA(nid)->node_id = nid;
310 	NODE_DATA(nid)->node_start_pfn = start_pfn;
311 	NODE_DATA(nid)->node_spanned_pages = end_pfn - start_pfn;
312 }
313 
314 /*
315  * numa_free_distance
316  *
317  * The current table is freed.
318  */
319 void __init numa_free_distance(void)
320 {
321 	size_t size;
322 
323 	if (!numa_distance)
324 		return;
325 
326 	size = numa_distance_cnt * numa_distance_cnt *
327 		sizeof(numa_distance[0]);
328 
329 	memblock_free(numa_distance, size);
330 	numa_distance_cnt = 0;
331 	numa_distance = NULL;
332 }
333 
334 /*
335  * Create a new NUMA distance table.
336  */
337 static int __init numa_alloc_distance(void)
338 {
339 	size_t size;
340 	int i, j;
341 
342 	size = nr_node_ids * nr_node_ids * sizeof(numa_distance[0]);
343 	numa_distance = memblock_alloc(size, PAGE_SIZE);
344 	if (WARN_ON(!numa_distance))
345 		return -ENOMEM;
346 
347 	numa_distance_cnt = nr_node_ids;
348 
349 	/* fill with the default distances */
350 	for (i = 0; i < numa_distance_cnt; i++)
351 		for (j = 0; j < numa_distance_cnt; j++)
352 			numa_distance[i * numa_distance_cnt + j] = i == j ?
353 				LOCAL_DISTANCE : REMOTE_DISTANCE;
354 
355 	pr_debug("Initialized distance table, cnt=%d\n", numa_distance_cnt);
356 
357 	return 0;
358 }
359 
360 /**
361  * numa_set_distance() - Set inter node NUMA distance from node to node.
362  * @from: the 'from' node to set distance
363  * @to: the 'to'  node to set distance
364  * @distance: NUMA distance
365  *
366  * Set the distance from node @from to @to to @distance.
367  * If distance table doesn't exist, a warning is printed.
368  *
369  * If @from or @to is higher than the highest known node or lower than zero
370  * or @distance doesn't make sense, the call is ignored.
371  */
372 void __init numa_set_distance(int from, int to, int distance)
373 {
374 	if (!numa_distance) {
375 		pr_warn_once("Warning: distance table not allocated yet\n");
376 		return;
377 	}
378 
379 	if (from >= numa_distance_cnt || to >= numa_distance_cnt ||
380 			from < 0 || to < 0) {
381 		pr_warn_once("Warning: node ids are out of bound, from=%d to=%d distance=%d\n",
382 			    from, to, distance);
383 		return;
384 	}
385 
386 	if ((u8)distance != distance ||
387 	    (from == to && distance != LOCAL_DISTANCE)) {
388 		pr_warn_once("Warning: invalid distance parameter, from=%d to=%d distance=%d\n",
389 			     from, to, distance);
390 		return;
391 	}
392 
393 	numa_distance[from * numa_distance_cnt + to] = distance;
394 }
395 
396 /*
397  * Return NUMA distance @from to @to
398  */
399 int __node_distance(int from, int to)
400 {
401 	if (from >= numa_distance_cnt || to >= numa_distance_cnt)
402 		return from == to ? LOCAL_DISTANCE : REMOTE_DISTANCE;
403 	return numa_distance[from * numa_distance_cnt + to];
404 }
405 EXPORT_SYMBOL(__node_distance);
406 
407 static int __init numa_register_nodes(void)
408 {
409 	int nid;
410 	struct memblock_region *mblk;
411 
412 	/* Check that valid nid is set to memblks */
413 	for_each_mem_region(mblk) {
414 		int mblk_nid = memblock_get_region_node(mblk);
415 		phys_addr_t start = mblk->base;
416 		phys_addr_t end = mblk->base + mblk->size - 1;
417 
418 		if (mblk_nid == NUMA_NO_NODE || mblk_nid >= MAX_NUMNODES) {
419 			pr_warn("Warning: invalid memblk node %d [mem %pap-%pap]\n",
420 				mblk_nid, &start, &end);
421 			return -EINVAL;
422 		}
423 	}
424 
425 	/* Finally register nodes. */
426 	for_each_node_mask(nid, numa_nodes_parsed) {
427 		unsigned long start_pfn, end_pfn;
428 
429 		get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
430 		setup_node_data(nid, start_pfn, end_pfn);
431 		node_set_online(nid);
432 	}
433 
434 	/* Setup online nodes to actual nodes*/
435 	node_possible_map = numa_nodes_parsed;
436 
437 	return 0;
438 }
439 
440 static int __init numa_init(int (*init_func)(void))
441 {
442 	int ret;
443 
444 	nodes_clear(numa_nodes_parsed);
445 	nodes_clear(node_possible_map);
446 	nodes_clear(node_online_map);
447 
448 	ret = numa_alloc_distance();
449 	if (ret < 0)
450 		return ret;
451 
452 	ret = init_func();
453 	if (ret < 0)
454 		goto out_free_distance;
455 
456 	if (nodes_empty(numa_nodes_parsed)) {
457 		pr_info("No NUMA configuration found\n");
458 		ret = -EINVAL;
459 		goto out_free_distance;
460 	}
461 
462 	ret = numa_register_nodes();
463 	if (ret < 0)
464 		goto out_free_distance;
465 
466 	setup_node_to_cpumask_map();
467 
468 	return 0;
469 out_free_distance:
470 	numa_free_distance();
471 	return ret;
472 }
473 
474 /**
475  * dummy_numa_init() - Fallback dummy NUMA init
476  *
477  * Used if there's no underlying NUMA architecture, NUMA initialization
478  * fails, or NUMA is disabled on the command line.
479  *
480  * Must online at least one node (node 0) and add memory blocks that cover all
481  * allowed memory. It is unlikely that this function fails.
482  *
483  * Return: 0 on success, -errno on failure.
484  */
485 static int __init dummy_numa_init(void)
486 {
487 	phys_addr_t start = memblock_start_of_DRAM();
488 	phys_addr_t end = memblock_end_of_DRAM() - 1;
489 	int ret;
490 
491 	if (numa_off)
492 		pr_info("NUMA disabled\n"); /* Forced off on command line. */
493 	pr_info("Faking a node at [mem %pap-%pap]\n", &start, &end);
494 
495 	ret = numa_add_memblk(0, start, end + 1);
496 	if (ret) {
497 		pr_err("NUMA init failed\n");
498 		return ret;
499 	}
500 
501 	numa_off = true;
502 	return 0;
503 }
504 
505 #ifdef CONFIG_ACPI_NUMA
506 static int __init arch_acpi_numa_init(void)
507 {
508 	int ret;
509 
510 	ret = acpi_numa_init();
511 	if (ret) {
512 		pr_info("Failed to initialise from firmware\n");
513 		return ret;
514 	}
515 
516 	return srat_disabled() ? -EINVAL : 0;
517 }
518 #else
519 static int __init arch_acpi_numa_init(void)
520 {
521 	return -EOPNOTSUPP;
522 }
523 #endif
524 
525 /**
526  * arch_numa_init() - Initialize NUMA
527  *
528  * Try each configured NUMA initialization method until one succeeds. The
529  * last fallback is dummy single node config encompassing whole memory.
530  */
531 void __init arch_numa_init(void)
532 {
533 	if (!numa_off) {
534 		if (!acpi_disabled && !numa_init(arch_acpi_numa_init))
535 			return;
536 		if (acpi_disabled && !numa_init(of_numa_init))
537 			return;
538 	}
539 
540 	numa_init(dummy_numa_init);
541 }
542