xref: /linux/mm/numa_memblks.c (revision 13b2d15d991b3f0f4ebfffbed081dbff27ac1c9d)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 
3 #include <linux/array_size.h>
4 #include <linux/sort.h>
5 #include <linux/printk.h>
6 #include <linux/memblock.h>
7 #include <linux/numa.h>
8 #include <linux/numa_memblks.h>
9 
10 #include <asm/numa.h>
11 
12 int numa_distance_cnt;
13 static u8 *numa_distance;
14 
15 nodemask_t numa_nodes_parsed __initdata;
16 
17 static struct numa_meminfo numa_meminfo __initdata_or_meminfo;
18 static struct numa_meminfo numa_reserved_meminfo __initdata_or_meminfo;
19 
20 /*
21  * Set nodes, which have memory in @mi, in *@nodemask.
22  */
numa_nodemask_from_meminfo(nodemask_t * nodemask,const struct numa_meminfo * mi)23 static void __init numa_nodemask_from_meminfo(nodemask_t *nodemask,
24 					      const struct numa_meminfo *mi)
25 {
26 	int i;
27 
28 	for (i = 0; i < ARRAY_SIZE(mi->blk); i++)
29 		if (mi->blk[i].start != mi->blk[i].end &&
30 		    mi->blk[i].nid != NUMA_NO_NODE)
31 			node_set(mi->blk[i].nid, *nodemask);
32 }
33 
34 /**
35  * numa_reset_distance - Reset NUMA distance table
36  *
37  * The current table is freed.  The next numa_set_distance() call will
38  * create a new one.
39  */
numa_reset_distance(void)40 void __init numa_reset_distance(void)
41 {
42 	size_t size = numa_distance_cnt * numa_distance_cnt * sizeof(numa_distance[0]);
43 
44 	/* numa_distance could be 1LU marking allocation failure, test cnt */
45 	if (numa_distance_cnt)
46 		memblock_free(numa_distance, size);
47 	numa_distance_cnt = 0;
48 	numa_distance = NULL;	/* enable table creation */
49 }
50 
numa_alloc_distance(void)51 static int __init numa_alloc_distance(void)
52 {
53 	nodemask_t nodes_parsed;
54 	size_t size;
55 	int i, j, cnt = 0;
56 
57 	/* size the new table and allocate it */
58 	nodes_parsed = numa_nodes_parsed;
59 	numa_nodemask_from_meminfo(&nodes_parsed, &numa_meminfo);
60 
61 	for_each_node_mask(i, nodes_parsed)
62 		cnt = i;
63 	cnt++;
64 	size = cnt * cnt * sizeof(numa_distance[0]);
65 
66 	numa_distance = memblock_alloc(size, PAGE_SIZE);
67 	if (!numa_distance) {
68 		pr_warn("Warning: can't allocate distance table!\n");
69 		/* don't retry until explicitly reset */
70 		numa_distance = (void *)1LU;
71 		return -ENOMEM;
72 	}
73 
74 	numa_distance_cnt = cnt;
75 
76 	/* fill with the default distances */
77 	for (i = 0; i < cnt; i++)
78 		for (j = 0; j < cnt; j++)
79 			numa_distance[i * cnt + j] = i == j ?
80 				LOCAL_DISTANCE : REMOTE_DISTANCE;
81 	pr_debug("NUMA: Initialized distance table, cnt=%d\n", cnt);
82 
83 	return 0;
84 }
85 
86 /**
87  * numa_set_distance - Set NUMA distance from one NUMA to another
88  * @from: the 'from' node to set distance
89  * @to: the 'to'  node to set distance
90  * @distance: NUMA distance
91  *
92  * Set the distance from node @from to @to to @distance.  If distance table
93  * doesn't exist, one which is large enough to accommodate all the currently
94  * known nodes will be created.
95  *
96  * If such table cannot be allocated, a warning is printed and further
97  * calls are ignored until the distance table is reset with
98  * numa_reset_distance().
99  *
100  * If @from or @to is higher than the highest known node or lower than zero
101  * at the time of table creation or @distance doesn't make sense, the call
102  * is ignored.
103  * This is to allow simplification of specific NUMA config implementations.
104  */
numa_set_distance(int from,int to,int distance)105 void __init numa_set_distance(int from, int to, int distance)
106 {
107 	if (!numa_distance && numa_alloc_distance() < 0)
108 		return;
109 
110 	if (from >= numa_distance_cnt || to >= numa_distance_cnt ||
111 			from < 0 || to < 0) {
112 		pr_warn_once("Warning: node ids are out of bound, from=%d to=%d distance=%d\n",
113 			     from, to, distance);
114 		return;
115 	}
116 
117 	if ((u8)distance != distance ||
118 	    (from == to && distance != LOCAL_DISTANCE)) {
119 		pr_warn_once("Warning: invalid distance parameter, from=%d to=%d distance=%d\n",
120 			     from, to, distance);
121 		return;
122 	}
123 
124 	numa_distance[from * numa_distance_cnt + to] = distance;
125 }
126 
__node_distance(int from,int to)127 int __node_distance(int from, int to)
128 {
129 	if (from >= numa_distance_cnt || to >= numa_distance_cnt)
130 		return from == to ? LOCAL_DISTANCE : REMOTE_DISTANCE;
131 	return numa_distance[from * numa_distance_cnt + to];
132 }
133 EXPORT_SYMBOL(__node_distance);
134 
numa_add_memblk_to(int nid,u64 start,u64 end,struct numa_meminfo * mi)135 static int __init numa_add_memblk_to(int nid, u64 start, u64 end,
136 				     struct numa_meminfo *mi)
137 {
138 	/* ignore zero length blks */
139 	if (start == end)
140 		return 0;
141 
142 	/* whine about and ignore invalid blks */
143 	if (start > end || nid < 0 || nid >= MAX_NUMNODES) {
144 		pr_warn("Warning: invalid memblk node %d [mem %#010Lx-%#010Lx]\n",
145 			nid, start, end - 1);
146 		return 0;
147 	}
148 
149 	if (mi->nr_blks >= NR_NODE_MEMBLKS) {
150 		pr_err("too many memblk ranges\n");
151 		return -EINVAL;
152 	}
153 
154 	mi->blk[mi->nr_blks].start = start;
155 	mi->blk[mi->nr_blks].end = end;
156 	mi->blk[mi->nr_blks].nid = nid;
157 	mi->nr_blks++;
158 	return 0;
159 }
160 
161 /**
162  * numa_remove_memblk_from - Remove one numa_memblk from a numa_meminfo
163  * @idx: Index of memblk to remove
164  * @mi: numa_meminfo to remove memblk from
165  *
166  * Remove @idx'th numa_memblk from @mi by shifting @mi->blk[] and
167  * decrementing @mi->nr_blks.
168  */
numa_remove_memblk_from(int idx,struct numa_meminfo * mi)169 void __init numa_remove_memblk_from(int idx, struct numa_meminfo *mi)
170 {
171 	mi->nr_blks--;
172 	memmove(&mi->blk[idx], &mi->blk[idx + 1],
173 		(mi->nr_blks - idx) * sizeof(mi->blk[0]));
174 }
175 
176 /**
177  * numa_move_tail_memblk - Move a numa_memblk from one numa_meminfo to another
178  * @dst: numa_meminfo to append block to
179  * @idx: Index of memblk to remove
180  * @src: numa_meminfo to remove memblk from
181  */
numa_move_tail_memblk(struct numa_meminfo * dst,int idx,struct numa_meminfo * src)182 static void __init numa_move_tail_memblk(struct numa_meminfo *dst, int idx,
183 					 struct numa_meminfo *src)
184 {
185 	dst->blk[dst->nr_blks++] = src->blk[idx];
186 	numa_remove_memblk_from(idx, src);
187 }
188 
189 /**
190  * numa_add_memblk - Add one numa_memblk to numa_meminfo
191  * @nid: NUMA node ID of the new memblk
192  * @start: Start address of the new memblk
193  * @end: End address of the new memblk
194  *
195  * Add a new memblk to the default numa_meminfo.
196  *
197  * RETURNS:
198  * 0 on success, -errno on failure.
199  */
numa_add_memblk(int nid,u64 start,u64 end)200 int __init numa_add_memblk(int nid, u64 start, u64 end)
201 {
202 	return numa_add_memblk_to(nid, start, end, &numa_meminfo);
203 }
204 
205 /**
206  * numa_add_reserved_memblk - Add one numa_memblk to numa_reserved_meminfo
207  * @nid: NUMA node ID of the new memblk
208  * @start: Start address of the new memblk
209  * @end: End address of the new memblk
210  *
211  * Add a new memblk to the numa_reserved_meminfo.
212  *
213  * Usage Case: numa_cleanup_meminfo() reconciles all numa_memblk instances
214  * against memblock_type information and moves any that intersect reserved
215  * ranges to numa_reserved_meminfo. However, when that information is known
216  * ahead of time, we use numa_add_reserved_memblk() to add the numa_memblk
217  * to numa_reserved_meminfo directly.
218  *
219  * RETURNS:
220  * 0 on success, -errno on failure.
221  */
numa_add_reserved_memblk(int nid,u64 start,u64 end)222 int __init numa_add_reserved_memblk(int nid, u64 start, u64 end)
223 {
224 	return numa_add_memblk_to(nid, start, end, &numa_reserved_meminfo);
225 }
226 
227 /**
228  * numa_cleanup_meminfo - Cleanup a numa_meminfo
229  * @mi: numa_meminfo to clean up
230  *
231  * Sanitize @mi by merging and removing unnecessary memblks.  Also check for
232  * conflicts and clear unused memblks.
233  *
234  * RETURNS:
235  * 0 on success, -errno on failure.
236  */
numa_cleanup_meminfo(struct numa_meminfo * mi)237 int __init numa_cleanup_meminfo(struct numa_meminfo *mi)
238 {
239 	const u64 low = memblock_start_of_DRAM();
240 	const u64 high = memblock_end_of_DRAM();
241 	int i, j, k;
242 
243 	/* first, trim all entries */
244 	for (i = 0; i < mi->nr_blks; i++) {
245 		struct numa_memblk *bi = &mi->blk[i];
246 
247 		/* move / save reserved memory ranges */
248 		if (!memblock_overlaps_region(&memblock.memory,
249 					bi->start, bi->end - bi->start)) {
250 			numa_move_tail_memblk(&numa_reserved_meminfo, i--, mi);
251 			continue;
252 		}
253 
254 		/* make sure all non-reserved blocks are inside the limits */
255 		bi->start = max(bi->start, low);
256 
257 		/* preserve info for non-RAM areas above 'max_pfn': */
258 		if (bi->end > high) {
259 			numa_add_memblk_to(bi->nid, high, bi->end,
260 					   &numa_reserved_meminfo);
261 			bi->end = high;
262 		}
263 
264 		/* and there's no empty block */
265 		if (bi->start >= bi->end)
266 			numa_remove_memblk_from(i--, mi);
267 	}
268 
269 	/* merge neighboring / overlapping entries */
270 	for (i = 0; i < mi->nr_blks; i++) {
271 		struct numa_memblk *bi = &mi->blk[i];
272 
273 		for (j = i + 1; j < mi->nr_blks; j++) {
274 			struct numa_memblk *bj = &mi->blk[j];
275 			u64 start, end;
276 
277 			/*
278 			 * See whether there are overlapping blocks.  Whine
279 			 * about but allow overlaps of the same nid.  They
280 			 * will be merged below.
281 			 */
282 			if (bi->end > bj->start && bi->start < bj->end) {
283 				if (bi->nid != bj->nid) {
284 					pr_err("node %d [mem %#010Lx-%#010Lx] overlaps with node %d [mem %#010Lx-%#010Lx]\n",
285 					       bi->nid, bi->start, bi->end - 1,
286 					       bj->nid, bj->start, bj->end - 1);
287 					return -EINVAL;
288 				}
289 				pr_warn("Warning: node %d [mem %#010Lx-%#010Lx] overlaps with itself [mem %#010Lx-%#010Lx]\n",
290 					bi->nid, bi->start, bi->end - 1,
291 					bj->start, bj->end - 1);
292 			}
293 
294 			/*
295 			 * Join together blocks on the same node, holes
296 			 * between which don't overlap with memory on other
297 			 * nodes.
298 			 */
299 			if (bi->nid != bj->nid)
300 				continue;
301 			start = min(bi->start, bj->start);
302 			end = max(bi->end, bj->end);
303 			for (k = 0; k < mi->nr_blks; k++) {
304 				struct numa_memblk *bk = &mi->blk[k];
305 
306 				if (bi->nid == bk->nid)
307 					continue;
308 				if (start < bk->end && end > bk->start)
309 					break;
310 			}
311 			if (k < mi->nr_blks)
312 				continue;
313 			pr_info("NUMA: Node %d [mem %#010Lx-%#010Lx] + [mem %#010Lx-%#010Lx] -> [mem %#010Lx-%#010Lx]\n",
314 			       bi->nid, bi->start, bi->end - 1, bj->start,
315 			       bj->end - 1, start, end - 1);
316 			bi->start = start;
317 			bi->end = end;
318 			numa_remove_memblk_from(j--, mi);
319 		}
320 	}
321 
322 	/* clear unused ones */
323 	for (i = mi->nr_blks; i < ARRAY_SIZE(mi->blk); i++) {
324 		mi->blk[i].start = mi->blk[i].end = 0;
325 		mi->blk[i].nid = NUMA_NO_NODE;
326 	}
327 
328 	return 0;
329 }
330 
331 /*
332  * Mark all currently memblock-reserved physical memory (which covers the
333  * kernel's own memory ranges) as hot-unswappable.
334  */
numa_clear_kernel_node_hotplug(void)335 static void __init numa_clear_kernel_node_hotplug(void)
336 {
337 	nodemask_t reserved_nodemask = NODE_MASK_NONE;
338 	struct memblock_region *mb_region;
339 	int i;
340 
341 	/*
342 	 * We have to do some preprocessing of memblock regions, to
343 	 * make them suitable for reservation.
344 	 *
345 	 * At this time, all memory regions reserved by memblock are
346 	 * used by the kernel, but those regions are not split up
347 	 * along node boundaries yet, and don't necessarily have their
348 	 * node ID set yet either.
349 	 *
350 	 * So iterate over all parsed memory blocks and use those ranges to
351 	 * set the nid in memblock.reserved.  This will split up the
352 	 * memblock regions along node boundaries and will set the node IDs
353 	 * as well.
354 	 */
355 	for (i = 0; i < numa_meminfo.nr_blks; i++) {
356 		struct numa_memblk *mb = numa_meminfo.blk + i;
357 		int ret;
358 
359 		ret = memblock_set_node(mb->start, mb->end - mb->start,
360 					&memblock.reserved, mb->nid);
361 		WARN_ON_ONCE(ret);
362 	}
363 
364 	/*
365 	 * Now go over all reserved memblock regions, to construct a
366 	 * node mask of all kernel reserved memory areas.
367 	 *
368 	 * [ Note, when booting with mem=nn[kMG] or in a kdump kernel,
369 	 *   numa_meminfo might not include all memblock.reserved
370 	 *   memory ranges, because quirks such as trim_snb_memory()
371 	 *   reserve specific pages for Sandy Bridge graphics. ]
372 	 */
373 	for_each_reserved_mem_region(mb_region) {
374 		int nid = memblock_get_region_node(mb_region);
375 
376 		if (numa_valid_node(nid))
377 			node_set(nid, reserved_nodemask);
378 	}
379 
380 	/*
381 	 * Finally, clear the MEMBLOCK_HOTPLUG flag for all memory
382 	 * belonging to the reserved node mask.
383 	 *
384 	 * Note that this will include memory regions that reside
385 	 * on nodes that contain kernel memory - entire nodes
386 	 * become hot-unpluggable:
387 	 */
388 	for (i = 0; i < numa_meminfo.nr_blks; i++) {
389 		struct numa_memblk *mb = numa_meminfo.blk + i;
390 
391 		if (!node_isset(mb->nid, reserved_nodemask))
392 			continue;
393 
394 		memblock_clear_hotplug(mb->start, mb->end - mb->start);
395 	}
396 }
397 
numa_register_meminfo(struct numa_meminfo * mi)398 static int __init numa_register_meminfo(struct numa_meminfo *mi)
399 {
400 	int i;
401 
402 	/* Account for nodes with cpus and no memory */
403 	node_possible_map = numa_nodes_parsed;
404 	numa_nodemask_from_meminfo(&node_possible_map, mi);
405 	if (WARN_ON(nodes_empty(node_possible_map)))
406 		return -EINVAL;
407 
408 	for (i = 0; i < mi->nr_blks; i++) {
409 		struct numa_memblk *mb = &mi->blk[i];
410 
411 		memblock_set_node(mb->start, mb->end - mb->start,
412 				  &memblock.memory, mb->nid);
413 	}
414 
415 	/*
416 	 * At very early time, the kernel have to use some memory such as
417 	 * loading the kernel image. We cannot prevent this anyway. So any
418 	 * node the kernel resides in should be un-hotpluggable.
419 	 *
420 	 * And when we come here, alloc node data won't fail.
421 	 */
422 	numa_clear_kernel_node_hotplug();
423 
424 	/*
425 	 * If sections array is gonna be used for pfn -> nid mapping, check
426 	 * whether its granularity is fine enough.
427 	 */
428 	if (IS_ENABLED(NODE_NOT_IN_PAGE_FLAGS)) {
429 		unsigned long pfn_align = node_map_pfn_alignment();
430 
431 		if (pfn_align && pfn_align < PAGES_PER_SECTION) {
432 			unsigned long node_align_mb = PFN_PHYS(pfn_align) / SZ_1M;
433 
434 			unsigned long sect_align_mb = PFN_PHYS(PAGES_PER_SECTION) / SZ_1M;
435 
436 			pr_warn("Node alignment %luMB < min %luMB, rejecting NUMA config\n",
437 				node_align_mb, sect_align_mb);
438 			return -EINVAL;
439 		}
440 	}
441 
442 	return 0;
443 }
444 
numa_memblks_init(int (* init_func)(void),bool memblock_force_top_down)445 int __init numa_memblks_init(int (*init_func)(void),
446 			     bool memblock_force_top_down)
447 {
448 	phys_addr_t max_addr = (phys_addr_t)ULLONG_MAX;
449 	int ret;
450 
451 	nodes_clear(numa_nodes_parsed);
452 	nodes_clear(node_possible_map);
453 	nodes_clear(node_online_map);
454 	memset(&numa_meminfo, 0, sizeof(numa_meminfo));
455 	WARN_ON(memblock_set_node(0, max_addr, &memblock.memory, NUMA_NO_NODE));
456 	WARN_ON(memblock_set_node(0, max_addr, &memblock.reserved,
457 				  NUMA_NO_NODE));
458 	/* In case that parsing SRAT failed. */
459 	WARN_ON(memblock_clear_hotplug(0, max_addr));
460 	numa_reset_distance();
461 
462 	ret = init_func();
463 	if (ret < 0)
464 		return ret;
465 
466 	/*
467 	 * We reset memblock back to the top-down direction
468 	 * here because if we configured ACPI_NUMA, we have
469 	 * parsed SRAT in init_func(). It is ok to have the
470 	 * reset here even if we did't configure ACPI_NUMA
471 	 * or acpi numa init fails and fallbacks to dummy
472 	 * numa init.
473 	 */
474 	if (memblock_force_top_down)
475 		memblock_set_bottom_up(false);
476 
477 	ret = numa_cleanup_meminfo(&numa_meminfo);
478 	if (ret < 0)
479 		return ret;
480 
481 	numa_emulation(&numa_meminfo, numa_distance_cnt);
482 
483 	return numa_register_meminfo(&numa_meminfo);
484 }
485 
cmp_memblk(const void * a,const void * b)486 static int __init cmp_memblk(const void *a, const void *b)
487 {
488 	const struct numa_memblk *ma = *(const struct numa_memblk **)a;
489 	const struct numa_memblk *mb = *(const struct numa_memblk **)b;
490 
491 	return (ma->start > mb->start) - (ma->start < mb->start);
492 }
493 
494 static struct numa_memblk *numa_memblk_list[NR_NODE_MEMBLKS] __initdata;
495 
496 /**
497  * numa_fill_memblks - Fill gaps in numa_meminfo memblks
498  * @start: address to begin fill
499  * @end: address to end fill
500  *
501  * Find and extend numa_meminfo memblks to cover the physical
502  * address range @start-@end
503  *
504  * RETURNS:
505  * 0		  : Success
506  * NUMA_NO_MEMBLK : No memblks exist in address range @start-@end
507  */
508 
numa_fill_memblks(u64 start,u64 end)509 int __init numa_fill_memblks(u64 start, u64 end)
510 {
511 	struct numa_memblk **blk = &numa_memblk_list[0];
512 	struct numa_meminfo *mi = &numa_meminfo;
513 	int count = 0;
514 	u64 prev_end;
515 
516 	/*
517 	 * Create a list of pointers to numa_meminfo memblks that
518 	 * overlap start, end. The list is used to make in-place
519 	 * changes that fill out the numa_meminfo memblks.
520 	 */
521 	for (int i = 0; i < mi->nr_blks; i++) {
522 		struct numa_memblk *bi = &mi->blk[i];
523 
524 		if (memblock_addrs_overlap(start, end - start, bi->start,
525 					   bi->end - bi->start)) {
526 			blk[count] = &mi->blk[i];
527 			count++;
528 		}
529 	}
530 	if (!count)
531 		return NUMA_NO_MEMBLK;
532 
533 	/* Sort the list of pointers in memblk->start order */
534 	sort(&blk[0], count, sizeof(blk[0]), cmp_memblk, NULL);
535 
536 	/* Make sure the first/last memblks include start/end */
537 	blk[0]->start = min(blk[0]->start, start);
538 	blk[count - 1]->end = max(blk[count - 1]->end, end);
539 
540 	/*
541 	 * Fill any gaps by tracking the previous memblks
542 	 * end address and backfilling to it if needed.
543 	 */
544 	prev_end = blk[0]->end;
545 	for (int i = 1; i < count; i++) {
546 		struct numa_memblk *curr = blk[i];
547 
548 		if (prev_end >= curr->start) {
549 			if (prev_end < curr->end)
550 				prev_end = curr->end;
551 		} else {
552 			curr->start = prev_end;
553 			prev_end = curr->end;
554 		}
555 	}
556 	return 0;
557 }
558 
559 #ifdef CONFIG_NUMA_KEEP_MEMINFO
meminfo_to_nid(struct numa_meminfo * mi,u64 start)560 static int meminfo_to_nid(struct numa_meminfo *mi, u64 start)
561 {
562 	int i;
563 
564 	for (i = 0; i < mi->nr_blks; i++)
565 		if (mi->blk[i].start <= start && mi->blk[i].end > start)
566 			return mi->blk[i].nid;
567 	return NUMA_NO_NODE;
568 }
569 
phys_to_target_node(u64 start)570 int phys_to_target_node(u64 start)
571 {
572 	int nid = meminfo_to_nid(&numa_meminfo, start);
573 
574 	/*
575 	 * Prefer online nodes, but if reserved memory might be
576 	 * hot-added continue the search with reserved ranges.
577 	 */
578 	if (nid != NUMA_NO_NODE)
579 		return nid;
580 
581 	return meminfo_to_nid(&numa_reserved_meminfo, start);
582 }
583 EXPORT_SYMBOL_GPL(phys_to_target_node);
584 
memory_add_physaddr_to_nid(u64 start)585 int memory_add_physaddr_to_nid(u64 start)
586 {
587 	int nid = meminfo_to_nid(&numa_meminfo, start);
588 
589 	if (nid == NUMA_NO_NODE)
590 		nid = numa_meminfo.blk[0].nid;
591 	return nid;
592 }
593 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
594 
595 #endif /* CONFIG_NUMA_KEEP_MEMINFO */
596