xref: /linux/drivers/base/arch_numa.c (revision da1d9caf95def6f0320819cf941c9fd1069ba9e1)
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 
18 struct pglist_data *node_data[MAX_NUMNODES] __read_mostly;
19 EXPORT_SYMBOL(node_data);
20 nodemask_t numa_nodes_parsed __initdata;
21 static int cpu_to_node_map[NR_CPUS] = { [0 ... NR_CPUS-1] = NUMA_NO_NODE };
22 
23 static int numa_distance_cnt;
24 static u8 *numa_distance;
25 bool numa_off;
26 
27 static __init int numa_parse_early_param(char *opt)
28 {
29 	if (!opt)
30 		return -EINVAL;
31 	if (str_has_prefix(opt, "off"))
32 		numa_off = true;
33 
34 	return 0;
35 }
36 early_param("numa", numa_parse_early_param);
37 
38 cpumask_var_t node_to_cpumask_map[MAX_NUMNODES];
39 EXPORT_SYMBOL(node_to_cpumask_map);
40 
41 #ifdef CONFIG_DEBUG_PER_CPU_MAPS
42 
43 /*
44  * Returns a pointer to the bitmask of CPUs on Node 'node'.
45  */
46 const struct cpumask *cpumask_of_node(int node)
47 {
48 
49 	if (node == NUMA_NO_NODE)
50 		return cpu_all_mask;
51 
52 	if (WARN_ON(node < 0 || node >= nr_node_ids))
53 		return cpu_none_mask;
54 
55 	if (WARN_ON(node_to_cpumask_map[node] == NULL))
56 		return cpu_online_mask;
57 
58 	return node_to_cpumask_map[node];
59 }
60 EXPORT_SYMBOL(cpumask_of_node);
61 
62 #endif
63 
64 static void numa_update_cpu(unsigned int cpu, bool remove)
65 {
66 	int nid = cpu_to_node(cpu);
67 
68 	if (nid == NUMA_NO_NODE)
69 		return;
70 
71 	if (remove)
72 		cpumask_clear_cpu(cpu, node_to_cpumask_map[nid]);
73 	else
74 		cpumask_set_cpu(cpu, node_to_cpumask_map[nid]);
75 }
76 
77 void numa_add_cpu(unsigned int cpu)
78 {
79 	numa_update_cpu(cpu, false);
80 }
81 
82 void numa_remove_cpu(unsigned int cpu)
83 {
84 	numa_update_cpu(cpu, true);
85 }
86 
87 void numa_clear_node(unsigned int cpu)
88 {
89 	numa_remove_cpu(cpu);
90 	set_cpu_numa_node(cpu, NUMA_NO_NODE);
91 }
92 
93 /*
94  * Allocate node_to_cpumask_map based on number of available nodes
95  * Requires node_possible_map to be valid.
96  *
97  * Note: cpumask_of_node() is not valid until after this is done.
98  * (Use CONFIG_DEBUG_PER_CPU_MAPS to check this.)
99  */
100 static void __init setup_node_to_cpumask_map(void)
101 {
102 	int node;
103 
104 	/* setup nr_node_ids if not done yet */
105 	if (nr_node_ids == MAX_NUMNODES)
106 		setup_nr_node_ids();
107 
108 	/* allocate and clear the mapping */
109 	for (node = 0; node < nr_node_ids; node++) {
110 		alloc_bootmem_cpumask_var(&node_to_cpumask_map[node]);
111 		cpumask_clear(node_to_cpumask_map[node]);
112 	}
113 
114 	/* cpumask_of_node() will now work */
115 	pr_debug("Node to cpumask map for %u nodes\n", nr_node_ids);
116 }
117 
118 /*
119  * Set the cpu to node and mem mapping
120  */
121 void numa_store_cpu_info(unsigned int cpu)
122 {
123 	set_cpu_numa_node(cpu, cpu_to_node_map[cpu]);
124 }
125 
126 void __init early_map_cpu_to_node(unsigned int cpu, int nid)
127 {
128 	/* fallback to node 0 */
129 	if (nid < 0 || nid >= MAX_NUMNODES || numa_off)
130 		nid = 0;
131 
132 	cpu_to_node_map[cpu] = nid;
133 
134 	/*
135 	 * We should set the numa node of cpu0 as soon as possible, because it
136 	 * has already been set up online before. cpu_to_node(0) will soon be
137 	 * called.
138 	 */
139 	if (!cpu)
140 		set_cpu_numa_node(cpu, nid);
141 }
142 
143 #ifdef CONFIG_HAVE_SETUP_PER_CPU_AREA
144 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
145 EXPORT_SYMBOL(__per_cpu_offset);
146 
147 static int __init early_cpu_to_node(int cpu)
148 {
149 	return cpu_to_node_map[cpu];
150 }
151 
152 static int __init pcpu_cpu_distance(unsigned int from, unsigned int to)
153 {
154 	return node_distance(early_cpu_to_node(from), early_cpu_to_node(to));
155 }
156 
157 void __init setup_per_cpu_areas(void)
158 {
159 	unsigned long delta;
160 	unsigned int cpu;
161 	int rc = -EINVAL;
162 
163 	if (pcpu_chosen_fc != PCPU_FC_PAGE) {
164 		/*
165 		 * Always reserve area for module percpu variables.  That's
166 		 * what the legacy allocator did.
167 		 */
168 		rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE,
169 					    PERCPU_DYNAMIC_RESERVE, PAGE_SIZE,
170 					    pcpu_cpu_distance,
171 					    early_cpu_to_node);
172 #ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
173 		if (rc < 0)
174 			pr_warn("PERCPU: %s allocator failed (%d), falling back to page size\n",
175 				   pcpu_fc_names[pcpu_chosen_fc], rc);
176 #endif
177 	}
178 
179 #ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
180 	if (rc < 0)
181 		rc = pcpu_page_first_chunk(PERCPU_MODULE_RESERVE, early_cpu_to_node);
182 #endif
183 	if (rc < 0)
184 		panic("Failed to initialize percpu areas (err=%d).", rc);
185 
186 	delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
187 	for_each_possible_cpu(cpu)
188 		__per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];
189 }
190 #endif
191 
192 /**
193  * numa_add_memblk() - Set node id to memblk
194  * @nid: NUMA node ID of the new memblk
195  * @start: Start address of the new memblk
196  * @end:  End address of the new memblk
197  *
198  * RETURNS:
199  * 0 on success, -errno on failure.
200  */
201 int __init numa_add_memblk(int nid, u64 start, u64 end)
202 {
203 	int ret;
204 
205 	ret = memblock_set_node(start, (end - start), &memblock.memory, nid);
206 	if (ret < 0) {
207 		pr_err("memblock [0x%llx - 0x%llx] failed to add on node %d\n",
208 			start, (end - 1), nid);
209 		return ret;
210 	}
211 
212 	node_set(nid, numa_nodes_parsed);
213 	return ret;
214 }
215 
216 /*
217  * Initialize NODE_DATA for a node on the local memory
218  */
219 static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn)
220 {
221 	const size_t nd_size = roundup(sizeof(pg_data_t), SMP_CACHE_BYTES);
222 	u64 nd_pa;
223 	void *nd;
224 	int tnid;
225 
226 	if (start_pfn >= end_pfn)
227 		pr_info("Initmem setup node %d [<memory-less node>]\n", nid);
228 
229 	nd_pa = memblock_phys_alloc_try_nid(nd_size, SMP_CACHE_BYTES, nid);
230 	if (!nd_pa)
231 		panic("Cannot allocate %zu bytes for node %d data\n",
232 		      nd_size, nid);
233 
234 	nd = __va(nd_pa);
235 
236 	/* report and initialize */
237 	pr_info("NODE_DATA [mem %#010Lx-%#010Lx]\n",
238 		nd_pa, nd_pa + nd_size - 1);
239 	tnid = early_pfn_to_nid(nd_pa >> PAGE_SHIFT);
240 	if (tnid != nid)
241 		pr_info("NODE_DATA(%d) on node %d\n", nid, tnid);
242 
243 	node_data[nid] = nd;
244 	memset(NODE_DATA(nid), 0, sizeof(pg_data_t));
245 	NODE_DATA(nid)->node_id = nid;
246 	NODE_DATA(nid)->node_start_pfn = start_pfn;
247 	NODE_DATA(nid)->node_spanned_pages = end_pfn - start_pfn;
248 }
249 
250 /*
251  * numa_free_distance
252  *
253  * The current table is freed.
254  */
255 void __init numa_free_distance(void)
256 {
257 	size_t size;
258 
259 	if (!numa_distance)
260 		return;
261 
262 	size = numa_distance_cnt * numa_distance_cnt *
263 		sizeof(numa_distance[0]);
264 
265 	memblock_free(numa_distance, size);
266 	numa_distance_cnt = 0;
267 	numa_distance = NULL;
268 }
269 
270 /*
271  * Create a new NUMA distance table.
272  */
273 static int __init numa_alloc_distance(void)
274 {
275 	size_t size;
276 	int i, j;
277 
278 	size = nr_node_ids * nr_node_ids * sizeof(numa_distance[0]);
279 	numa_distance = memblock_alloc(size, PAGE_SIZE);
280 	if (WARN_ON(!numa_distance))
281 		return -ENOMEM;
282 
283 	numa_distance_cnt = nr_node_ids;
284 
285 	/* fill with the default distances */
286 	for (i = 0; i < numa_distance_cnt; i++)
287 		for (j = 0; j < numa_distance_cnt; j++)
288 			numa_distance[i * numa_distance_cnt + j] = i == j ?
289 				LOCAL_DISTANCE : REMOTE_DISTANCE;
290 
291 	pr_debug("Initialized distance table, cnt=%d\n", numa_distance_cnt);
292 
293 	return 0;
294 }
295 
296 /**
297  * numa_set_distance() - Set inter node NUMA distance from node to node.
298  * @from: the 'from' node to set distance
299  * @to: the 'to'  node to set distance
300  * @distance: NUMA distance
301  *
302  * Set the distance from node @from to @to to @distance.
303  * If distance table doesn't exist, a warning is printed.
304  *
305  * If @from or @to is higher than the highest known node or lower than zero
306  * or @distance doesn't make sense, the call is ignored.
307  */
308 void __init numa_set_distance(int from, int to, int distance)
309 {
310 	if (!numa_distance) {
311 		pr_warn_once("Warning: distance table not allocated yet\n");
312 		return;
313 	}
314 
315 	if (from >= numa_distance_cnt || to >= numa_distance_cnt ||
316 			from < 0 || to < 0) {
317 		pr_warn_once("Warning: node ids are out of bound, from=%d to=%d distance=%d\n",
318 			    from, to, distance);
319 		return;
320 	}
321 
322 	if ((u8)distance != distance ||
323 	    (from == to && distance != LOCAL_DISTANCE)) {
324 		pr_warn_once("Warning: invalid distance parameter, from=%d to=%d distance=%d\n",
325 			     from, to, distance);
326 		return;
327 	}
328 
329 	numa_distance[from * numa_distance_cnt + to] = distance;
330 }
331 
332 /*
333  * Return NUMA distance @from to @to
334  */
335 int __node_distance(int from, int to)
336 {
337 	if (from >= numa_distance_cnt || to >= numa_distance_cnt)
338 		return from == to ? LOCAL_DISTANCE : REMOTE_DISTANCE;
339 	return numa_distance[from * numa_distance_cnt + to];
340 }
341 EXPORT_SYMBOL(__node_distance);
342 
343 static int __init numa_register_nodes(void)
344 {
345 	int nid;
346 	struct memblock_region *mblk;
347 
348 	/* Check that valid nid is set to memblks */
349 	for_each_mem_region(mblk) {
350 		int mblk_nid = memblock_get_region_node(mblk);
351 		phys_addr_t start = mblk->base;
352 		phys_addr_t end = mblk->base + mblk->size - 1;
353 
354 		if (mblk_nid == NUMA_NO_NODE || mblk_nid >= MAX_NUMNODES) {
355 			pr_warn("Warning: invalid memblk node %d [mem %pap-%pap]\n",
356 				mblk_nid, &start, &end);
357 			return -EINVAL;
358 		}
359 	}
360 
361 	/* Finally register nodes. */
362 	for_each_node_mask(nid, numa_nodes_parsed) {
363 		unsigned long start_pfn, end_pfn;
364 
365 		get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
366 		setup_node_data(nid, start_pfn, end_pfn);
367 		node_set_online(nid);
368 	}
369 
370 	/* Setup online nodes to actual nodes*/
371 	node_possible_map = numa_nodes_parsed;
372 
373 	return 0;
374 }
375 
376 static int __init numa_init(int (*init_func)(void))
377 {
378 	int ret;
379 
380 	nodes_clear(numa_nodes_parsed);
381 	nodes_clear(node_possible_map);
382 	nodes_clear(node_online_map);
383 
384 	ret = numa_alloc_distance();
385 	if (ret < 0)
386 		return ret;
387 
388 	ret = init_func();
389 	if (ret < 0)
390 		goto out_free_distance;
391 
392 	if (nodes_empty(numa_nodes_parsed)) {
393 		pr_info("No NUMA configuration found\n");
394 		ret = -EINVAL;
395 		goto out_free_distance;
396 	}
397 
398 	ret = numa_register_nodes();
399 	if (ret < 0)
400 		goto out_free_distance;
401 
402 	setup_node_to_cpumask_map();
403 
404 	return 0;
405 out_free_distance:
406 	numa_free_distance();
407 	return ret;
408 }
409 
410 /**
411  * dummy_numa_init() - Fallback dummy NUMA init
412  *
413  * Used if there's no underlying NUMA architecture, NUMA initialization
414  * fails, or NUMA is disabled on the command line.
415  *
416  * Must online at least one node (node 0) and add memory blocks that cover all
417  * allowed memory. It is unlikely that this function fails.
418  *
419  * Return: 0 on success, -errno on failure.
420  */
421 static int __init dummy_numa_init(void)
422 {
423 	phys_addr_t start = memblock_start_of_DRAM();
424 	phys_addr_t end = memblock_end_of_DRAM() - 1;
425 	int ret;
426 
427 	if (numa_off)
428 		pr_info("NUMA disabled\n"); /* Forced off on command line. */
429 	pr_info("Faking a node at [mem %pap-%pap]\n", &start, &end);
430 
431 	ret = numa_add_memblk(0, start, end + 1);
432 	if (ret) {
433 		pr_err("NUMA init failed\n");
434 		return ret;
435 	}
436 
437 	numa_off = true;
438 	return 0;
439 }
440 
441 #ifdef CONFIG_ACPI_NUMA
442 static int __init arch_acpi_numa_init(void)
443 {
444 	int ret;
445 
446 	ret = acpi_numa_init();
447 	if (ret) {
448 		pr_info("Failed to initialise from firmware\n");
449 		return ret;
450 	}
451 
452 	return srat_disabled() ? -EINVAL : 0;
453 }
454 #else
455 static int __init arch_acpi_numa_init(void)
456 {
457 	return -EOPNOTSUPP;
458 }
459 #endif
460 
461 /**
462  * arch_numa_init() - Initialize NUMA
463  *
464  * Try each configured NUMA initialization method until one succeeds. The
465  * last fallback is dummy single node config encompassing whole memory.
466  */
467 void __init arch_numa_init(void)
468 {
469 	if (!numa_off) {
470 		if (!acpi_disabled && !numa_init(arch_acpi_numa_init))
471 			return;
472 		if (acpi_disabled && !numa_init(of_numa_init))
473 			return;
474 	}
475 
476 	numa_init(dummy_numa_init);
477 }
478