xref: /freebsd/sys/dev/acpica/acpi_pxm.c (revision 06c3fb2749bda94cb5201f81ffdb8fa6c3161b2e)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2010 Hudson River Trading LLC
5  * Written by: John H. Baldwin <jhb@FreeBSD.org>
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 #include "opt_vm.h"
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/bus.h>
36 #include <sys/kernel.h>
37 #include <sys/lock.h>
38 #include <sys/mutex.h>
39 #include <sys/smp.h>
40 #include <sys/vmmeter.h>
41 #include <vm/vm.h>
42 #include <vm/pmap.h>
43 #include <vm/vm_param.h>
44 #include <vm/vm_page.h>
45 #include <vm/vm_phys.h>
46 
47 #include <contrib/dev/acpica/include/acpi.h>
48 #include <contrib/dev/acpica/include/aclocal.h>
49 #include <contrib/dev/acpica/include/actables.h>
50 
51 #include <machine/md_var.h>
52 
53 #include <dev/acpica/acpivar.h>
54 
55 #if MAXMEMDOM > 1
56 static struct cpu_info {
57 	bool enabled:1;
58 	bool has_memory:1;
59 	int domain;
60 	int id;
61 } *cpus;
62 
63 static int max_cpus;
64 static int last_cpu;
65 
66 struct mem_affinity mem_info[VM_PHYSSEG_MAX + 1];
67 int num_mem;
68 
69 static ACPI_TABLE_SRAT *srat;
70 static vm_paddr_t srat_physaddr;
71 
72 static int domain_pxm[MAXMEMDOM];
73 static int ndomain;
74 static vm_paddr_t maxphyaddr;
75 
76 static ACPI_TABLE_SLIT *slit;
77 static vm_paddr_t slit_physaddr;
78 static int vm_locality_table[MAXMEMDOM * MAXMEMDOM];
79 
80 static void	srat_walk_table(acpi_subtable_handler *handler, void *arg);
81 
82 /*
83  * SLIT parsing.
84  */
85 
86 static void
87 slit_parse_table(ACPI_TABLE_SLIT *s)
88 {
89 	int i, j;
90 	int i_domain, j_domain;
91 	int offset = 0;
92 	uint8_t e;
93 
94 	/*
95 	 * This maps the SLIT data into the VM-domain centric view.
96 	 * There may be sparse entries in the PXM namespace, so
97 	 * remap them to a VM-domain ID and if it doesn't exist,
98 	 * skip it.
99 	 *
100 	 * It should result in a packed 2d array of VM-domain
101 	 * locality information entries.
102 	 */
103 
104 	if (bootverbose)
105 		printf("SLIT.Localities: %d\n", (int) s->LocalityCount);
106 	for (i = 0; i < s->LocalityCount; i++) {
107 		i_domain = acpi_map_pxm_to_vm_domainid(i);
108 		if (i_domain < 0)
109 			continue;
110 
111 		if (bootverbose)
112 			printf("%d: ", i);
113 		for (j = 0; j < s->LocalityCount; j++) {
114 			j_domain = acpi_map_pxm_to_vm_domainid(j);
115 			if (j_domain < 0)
116 				continue;
117 			e = s->Entry[i * s->LocalityCount + j];
118 			if (bootverbose)
119 				printf("%d ", (int) e);
120 			/* 255 == "no locality information" */
121 			if (e == 255)
122 				vm_locality_table[offset] = -1;
123 			else
124 				vm_locality_table[offset] = e;
125 			offset++;
126 		}
127 		if (bootverbose)
128 			printf("\n");
129 	}
130 }
131 
132 /*
133  * Look for an ACPI System Locality Distance Information Table ("SLIT")
134  */
135 static int
136 parse_slit(void)
137 {
138 
139 	if (resource_disabled("slit", 0)) {
140 		return (-1);
141 	}
142 
143 	slit_physaddr = acpi_find_table(ACPI_SIG_SLIT);
144 	if (slit_physaddr == 0) {
145 		return (-1);
146 	}
147 
148 	/*
149 	 * Make a pass over the table to populate the cpus[] and
150 	 * mem_info[] tables.
151 	 */
152 	slit = acpi_map_table(slit_physaddr, ACPI_SIG_SLIT);
153 	slit_parse_table(slit);
154 	acpi_unmap_table(slit);
155 	slit = NULL;
156 
157 	return (0);
158 }
159 
160 /*
161  * SRAT parsing.
162  */
163 
164 /*
165  * Returns true if a memory range overlaps with at least one range in
166  * phys_avail[].
167  */
168 static int
169 overlaps_phys_avail(vm_paddr_t start, vm_paddr_t end)
170 {
171 	int i;
172 
173 	for (i = 0; phys_avail[i] != 0 && phys_avail[i + 1] != 0; i += 2) {
174 		if (phys_avail[i + 1] <= start)
175 			continue;
176 		if (phys_avail[i] < end)
177 			return (1);
178 		break;
179 	}
180 	return (0);
181 }
182 
183 /*
184  * On x86 we can use the cpuid to index the cpus array, but on arm64
185  * we have an ACPI Processor UID with a larger range.
186  *
187  * Use this variable to indicate if the cpus can be stored by index.
188  */
189 #ifdef __aarch64__
190 static const int cpus_use_indexing = 0;
191 #else
192 static const int cpus_use_indexing = 1;
193 #endif
194 
195 /*
196  * Find CPU by processor ID (APIC ID on x86, Processor UID on arm64)
197  */
198 static struct cpu_info *
199 cpu_find(int cpuid)
200 {
201 	int i;
202 
203 	if (cpus_use_indexing) {
204 		if (cpuid <= last_cpu && cpus[cpuid].enabled)
205 			return (&cpus[cpuid]);
206 	} else {
207 		for (i = 0; i <= last_cpu; i++)
208 			if (cpus[i].id == cpuid)
209 				return (&cpus[i]);
210 	}
211 	return (NULL);
212 }
213 
214 /*
215  * Find CPU by pcpu pointer.
216  */
217 static struct cpu_info *
218 cpu_get_info(struct pcpu *pc)
219 {
220 	struct cpu_info *cpup;
221 	int id;
222 
223 #ifdef __aarch64__
224 	id = pc->pc_acpi_id;
225 #else
226 	id = pc->pc_apic_id;
227 #endif
228 	cpup = cpu_find(id);
229 	if (cpup == NULL)
230 		panic("SRAT: CPU with ID %u is not known", id);
231 	return (cpup);
232 }
233 
234 /*
235  * Add proximity information for a new CPU.
236  */
237 static struct cpu_info *
238 cpu_add(int cpuid, int domain)
239 {
240 	struct cpu_info *cpup;
241 
242 	if (cpus_use_indexing) {
243 		if (cpuid >= max_cpus)
244 			return (NULL);
245 		last_cpu = imax(last_cpu, cpuid);
246 		cpup = &cpus[cpuid];
247 	} else {
248 		if (last_cpu >= max_cpus - 1)
249 			return (NULL);
250 		cpup = &cpus[++last_cpu];
251 	}
252 	cpup->domain = domain;
253 	cpup->id = cpuid;
254 	cpup->enabled = 1;
255 	return (cpup);
256 }
257 
258 static void
259 srat_parse_entry(ACPI_SUBTABLE_HEADER *entry, void *arg)
260 {
261 	ACPI_SRAT_CPU_AFFINITY *cpu;
262 	ACPI_SRAT_X2APIC_CPU_AFFINITY *x2apic;
263 	ACPI_SRAT_MEM_AFFINITY *mem;
264 	ACPI_SRAT_GICC_AFFINITY *gicc;
265 	static struct cpu_info *cpup;
266 	uint64_t base, length;
267 	int domain, i, slot;
268 
269 	switch (entry->Type) {
270 	case ACPI_SRAT_TYPE_CPU_AFFINITY:
271 		cpu = (ACPI_SRAT_CPU_AFFINITY *)entry;
272 		domain = cpu->ProximityDomainLo |
273 		    cpu->ProximityDomainHi[0] << 8 |
274 		    cpu->ProximityDomainHi[1] << 16 |
275 		    cpu->ProximityDomainHi[2] << 24;
276 		if (bootverbose)
277 			printf("SRAT: Found CPU APIC ID %u domain %d: %s\n",
278 			    cpu->ApicId, domain,
279 			    (cpu->Flags & ACPI_SRAT_CPU_ENABLED) ?
280 			    "enabled" : "disabled");
281 		if (!(cpu->Flags & ACPI_SRAT_CPU_ENABLED))
282 			break;
283 		cpup = cpu_find(cpu->ApicId);
284 		if (cpup != NULL) {
285 			printf("SRAT: Duplicate local APIC ID %u\n",
286 			    cpu->ApicId);
287 			*(int *)arg = ENXIO;
288 			break;
289 		}
290 		cpup = cpu_add(cpu->ApicId, domain);
291 		if (cpup == NULL)
292 			printf("SRAT: Ignoring local APIC ID %u (too high)\n",
293 			    cpu->ApicId);
294 		break;
295 	case ACPI_SRAT_TYPE_X2APIC_CPU_AFFINITY:
296 		x2apic = (ACPI_SRAT_X2APIC_CPU_AFFINITY *)entry;
297 		if (bootverbose)
298 			printf("SRAT: Found CPU APIC ID %u domain %d: %s\n",
299 			    x2apic->ApicId, x2apic->ProximityDomain,
300 			    (x2apic->Flags & ACPI_SRAT_CPU_ENABLED) ?
301 			    "enabled" : "disabled");
302 		if (!(x2apic->Flags & ACPI_SRAT_CPU_ENABLED))
303 			break;
304 		KASSERT(cpu_find(x2apic->ApicId) == NULL,
305 		    ("Duplicate local APIC ID %u", x2apic->ApicId));
306 		cpup = cpu_add(x2apic->ApicId, x2apic->ProximityDomain);
307 		if (cpup == NULL)
308 			printf("SRAT: Ignoring local APIC ID %u (too high)\n",
309 			    x2apic->ApicId);
310 		break;
311 	case ACPI_SRAT_TYPE_GICC_AFFINITY:
312 		gicc = (ACPI_SRAT_GICC_AFFINITY *)entry;
313 		if (bootverbose)
314 			printf("SRAT: Found CPU UID %u domain %d: %s\n",
315 			    gicc->AcpiProcessorUid, gicc->ProximityDomain,
316 			    (gicc->Flags & ACPI_SRAT_GICC_ENABLED) ?
317 			    "enabled" : "disabled");
318 		if (!(gicc->Flags & ACPI_SRAT_GICC_ENABLED))
319 			break;
320 		KASSERT(cpu_find(gicc->AcpiProcessorUid) == NULL,
321 		    ("Duplicate CPU UID %u", gicc->AcpiProcessorUid));
322 		cpup = cpu_add(gicc->AcpiProcessorUid, gicc->ProximityDomain);
323 		if (cpup == NULL)
324 			printf("SRAT: Ignoring CPU UID %u (too high)\n",
325 			    gicc->AcpiProcessorUid);
326 		break;
327 	case ACPI_SRAT_TYPE_MEMORY_AFFINITY:
328 		mem = (ACPI_SRAT_MEM_AFFINITY *)entry;
329 		base = mem->BaseAddress;
330 		length = mem->Length;
331 		domain = mem->ProximityDomain;
332 
333 		if (bootverbose)
334 			printf(
335 		    "SRAT: Found memory domain %d addr 0x%jx len 0x%jx: %s\n",
336 			    domain, (uintmax_t)base, (uintmax_t)length,
337 			    (mem->Flags & ACPI_SRAT_MEM_ENABLED) ?
338 			    "enabled" : "disabled");
339 		if (!(mem->Flags & ACPI_SRAT_MEM_ENABLED))
340 			break;
341 		if (base >= maxphyaddr ||
342 		    !overlaps_phys_avail(base, base + length)) {
343 			printf("SRAT: Ignoring memory at addr 0x%jx\n",
344 			    (uintmax_t)base);
345 			break;
346 		}
347 		if (num_mem == VM_PHYSSEG_MAX) {
348 			printf("SRAT: Too many memory regions\n");
349 			*(int *)arg = ENXIO;
350 			break;
351 		}
352 		slot = num_mem;
353 		for (i = 0; i < num_mem; i++) {
354 			if (mem_info[i].domain == domain) {
355 				/* Try to extend an existing segment. */
356 				if (base == mem_info[i].end) {
357 					mem_info[i].end += length;
358 					return;
359 				}
360 				if (base + length == mem_info[i].start) {
361 					mem_info[i].start -= length;
362 					return;
363 				}
364 			}
365 			if (mem_info[i].end <= base)
366 				continue;
367 			if (mem_info[i].start < base + length) {
368 				printf("SRAT: Overlapping memory entries\n");
369 				*(int *)arg = ENXIO;
370 				return;
371 			}
372 			slot = i;
373 		}
374 		for (i = num_mem; i > slot; i--)
375 			mem_info[i] = mem_info[i - 1];
376 		mem_info[slot].start = base;
377 		mem_info[slot].end = base + length;
378 		mem_info[slot].domain = domain;
379 		num_mem++;
380 		break;
381 	}
382 }
383 
384 /*
385  * Ensure each memory domain has at least one CPU and that each CPU
386  * has at least one memory domain.
387  */
388 static int
389 check_domains(void)
390 {
391 	int found, i, j;
392 
393 	for (i = 0; i < num_mem; i++) {
394 		found = 0;
395 		for (j = 0; j <= last_cpu; j++)
396 			if (cpus[j].enabled &&
397 			    cpus[j].domain == mem_info[i].domain) {
398 				cpus[j].has_memory = 1;
399 				found++;
400 			}
401 		if (!found) {
402 			printf("SRAT: No CPU found for memory domain %d\n",
403 			    mem_info[i].domain);
404 			return (ENXIO);
405 		}
406 	}
407 	for (i = 0; i <= last_cpu; i++)
408 		if (cpus[i].enabled && !cpus[i].has_memory) {
409 			found = 0;
410 			for (j = 0; j < num_mem && !found; j++) {
411 				if (mem_info[j].domain == cpus[i].domain)
412 					found = 1;
413 			}
414 			if (!found) {
415 				if (bootverbose)
416 					printf("SRAT: mem dom %d is empty\n",
417 					    cpus[i].domain);
418 				mem_info[num_mem].start = 0;
419 				mem_info[num_mem].end = 0;
420 				mem_info[num_mem].domain = cpus[i].domain;
421 				num_mem++;
422 			}
423 		}
424 	return (0);
425 }
426 
427 /*
428  * Check that the SRAT memory regions cover all of the regions in
429  * phys_avail[].
430  */
431 static int
432 check_phys_avail(void)
433 {
434 	vm_paddr_t address;
435 	int i, j;
436 
437 	/* j is the current offset into phys_avail[]. */
438 	address = phys_avail[0];
439 	j = 0;
440 	for (i = 0; i < num_mem; i++) {
441 		/*
442 		 * Consume as many phys_avail[] entries as fit in this
443 		 * region.
444 		 */
445 		while (address >= mem_info[i].start &&
446 		    address <= mem_info[i].end) {
447 			/*
448 			 * If we cover the rest of this phys_avail[] entry,
449 			 * advance to the next entry.
450 			 */
451 			if (phys_avail[j + 1] <= mem_info[i].end) {
452 				j += 2;
453 				if (phys_avail[j] == 0 &&
454 				    phys_avail[j + 1] == 0) {
455 					return (0);
456 				}
457 				address = phys_avail[j];
458 			} else
459 				address = mem_info[i].end + 1;
460 		}
461 	}
462 	printf("SRAT: No memory region found for 0x%jx - 0x%jx\n",
463 	    (uintmax_t)phys_avail[j], (uintmax_t)phys_avail[j + 1]);
464 	return (ENXIO);
465 }
466 
467 /*
468  * Renumber the memory domains to be compact and zero-based if not
469  * already.  Returns an error if there are too many domains.
470  */
471 static int
472 renumber_domains(void)
473 {
474 	int i, j, slot;
475 
476 	/* Enumerate all the domains. */
477 	ndomain = 0;
478 	for (i = 0; i < num_mem; i++) {
479 		/* See if this domain is already known. */
480 		for (j = 0; j < ndomain; j++) {
481 			if (domain_pxm[j] >= mem_info[i].domain)
482 				break;
483 		}
484 		if (j < ndomain && domain_pxm[j] == mem_info[i].domain)
485 			continue;
486 
487 		if (ndomain >= MAXMEMDOM) {
488 			ndomain = 1;
489 			printf("SRAT: Too many memory domains\n");
490 			return (EFBIG);
491 		}
492 
493 		/* Insert the new domain at slot 'j'. */
494 		slot = j;
495 		for (j = ndomain; j > slot; j--)
496 			domain_pxm[j] = domain_pxm[j - 1];
497 		domain_pxm[slot] = mem_info[i].domain;
498 		ndomain++;
499 	}
500 
501 	/* Renumber each domain to its index in the sorted 'domain_pxm' list. */
502 	for (i = 0; i < ndomain; i++) {
503 		/*
504 		 * If the domain is already the right value, no need
505 		 * to renumber.
506 		 */
507 		if (domain_pxm[i] == i)
508 			continue;
509 
510 		/* Walk the cpu[] and mem_info[] arrays to renumber. */
511 		for (j = 0; j < num_mem; j++)
512 			if (mem_info[j].domain == domain_pxm[i])
513 				mem_info[j].domain = i;
514 		for (j = 0; j <= last_cpu; j++)
515 			if (cpus[j].enabled && cpus[j].domain == domain_pxm[i])
516 				cpus[j].domain = i;
517 	}
518 
519 	return (0);
520 }
521 
522 /*
523  * Look for an ACPI System Resource Affinity Table ("SRAT"),
524  * allocate space for cpu information, and initialize globals.
525  */
526 int
527 acpi_pxm_init(int ncpus, vm_paddr_t maxphys)
528 {
529 	unsigned int idx, size;
530 	vm_paddr_t addr;
531 
532 	if (resource_disabled("srat", 0))
533 		return (-1);
534 
535 	max_cpus = ncpus;
536 	last_cpu = -1;
537 	maxphyaddr = maxphys;
538 	srat_physaddr = acpi_find_table(ACPI_SIG_SRAT);
539 	if (srat_physaddr == 0)
540 		return (-1);
541 
542 	/*
543 	 * Allocate data structure:
544 	 *
545 	 * Find the last physical memory region and steal some memory from
546 	 * it. This is done because at this point in the boot process
547 	 * malloc is still not usable.
548 	 */
549 	for (idx = 0; phys_avail[idx + 1] != 0; idx += 2);
550 	KASSERT(idx != 0, ("phys_avail is empty!"));
551 	idx -= 2;
552 
553 	size =  sizeof(*cpus) * max_cpus;
554 	addr = trunc_page(phys_avail[idx + 1] - size);
555 	KASSERT(addr >= phys_avail[idx],
556 	    ("Not enough memory for SRAT table items"));
557 	phys_avail[idx + 1] = addr - 1;
558 
559 	/*
560 	 * We cannot rely on PHYS_TO_DMAP because this code is also used in
561 	 * i386, so use pmap_mapbios to map the memory, this will end up using
562 	 * the default memory attribute (WB), and the DMAP when available.
563 	 */
564 	cpus = (struct cpu_info *)pmap_mapbios(addr, size);
565 	bzero(cpus, size);
566 	return (0);
567 }
568 
569 static int
570 parse_srat(void)
571 {
572 	int error;
573 
574 	/*
575 	 * Make a pass over the table to populate the cpus[] and
576 	 * mem_info[] tables.
577 	 */
578 	srat = acpi_map_table(srat_physaddr, ACPI_SIG_SRAT);
579 	error = 0;
580 	srat_walk_table(srat_parse_entry, &error);
581 	acpi_unmap_table(srat);
582 	srat = NULL;
583 	if (error || check_domains() != 0 || check_phys_avail() != 0 ||
584 	    renumber_domains() != 0) {
585 		srat_physaddr = 0;
586 		return (-1);
587 	}
588 
589 	return (0);
590 }
591 
592 static void
593 init_mem_locality(void)
594 {
595 	int i;
596 
597 	/*
598 	 * For now, assume -1 == "no locality information for
599 	 * this pairing.
600 	 */
601 	for (i = 0; i < MAXMEMDOM * MAXMEMDOM; i++)
602 		vm_locality_table[i] = -1;
603 }
604 
605 /*
606  * Parse SRAT and SLIT to save proximity info. Don't do
607  * anything if SRAT is not available.
608  */
609 void
610 acpi_pxm_parse_tables(void)
611 {
612 
613 	if (srat_physaddr == 0)
614 		return;
615 	if (parse_srat() < 0)
616 		return;
617 	init_mem_locality();
618 	(void)parse_slit();
619 }
620 
621 /*
622  * Use saved data from SRAT/SLIT to update memory locality.
623  */
624 void
625 acpi_pxm_set_mem_locality(void)
626 {
627 
628 	if (srat_physaddr == 0)
629 		return;
630 	vm_phys_register_domains(ndomain, mem_info, vm_locality_table);
631 }
632 
633 static void
634 srat_walk_table(acpi_subtable_handler *handler, void *arg)
635 {
636 
637 	acpi_walk_subtables(srat + 1, (char *)srat + srat->Header.Length,
638 	    handler, arg);
639 }
640 
641 /*
642  * Set up per-CPU domain IDs from information saved in 'cpus' and tear down data
643  * structures allocated by acpi_pxm_init().
644  */
645 void
646 acpi_pxm_set_cpu_locality(void)
647 {
648 	struct cpu_info *cpu;
649 	struct pcpu *pc;
650 	u_int i;
651 
652 	if (srat_physaddr == 0)
653 		return;
654 	for (i = 0; i < MAXCPU; i++) {
655 		if (CPU_ABSENT(i))
656 			continue;
657 		pc = pcpu_find(i);
658 		KASSERT(pc != NULL, ("no pcpu data for CPU %u", i));
659 		cpu = cpu_get_info(pc);
660 		pc->pc_domain = vm_ndomains > 1 ? cpu->domain : 0;
661 		CPU_SET(i, &cpuset_domain[pc->pc_domain]);
662 		if (bootverbose)
663 			printf("SRAT: CPU %u has memory domain %d\n", i,
664 			    pc->pc_domain);
665 	}
666 	/* XXXMJ the page is leaked. */
667 	pmap_unmapbios(cpus, sizeof(*cpus) * max_cpus);
668 	srat_physaddr = 0;
669 	cpus = NULL;
670 }
671 
672 int
673 acpi_pxm_get_cpu_locality(int apic_id)
674 {
675 	struct cpu_info *cpu;
676 
677 	cpu = cpu_find(apic_id);
678 	if (cpu == NULL)
679 		panic("SRAT: CPU with ID %u is not known", apic_id);
680 	return (cpu->domain);
681 }
682 
683 /*
684  * Map a _PXM value to a VM domain ID.
685  *
686  * Returns the domain ID, or -1 if no domain ID was found.
687  */
688 int
689 acpi_map_pxm_to_vm_domainid(int pxm)
690 {
691 	int i;
692 
693 	for (i = 0; i < ndomain; i++) {
694 		if (domain_pxm[i] == pxm)
695 			return (vm_ndomains > 1 ? i : 0);
696 	}
697 
698 	return (-1);
699 }
700 
701 #else /* MAXMEMDOM == 1 */
702 
703 int
704 acpi_map_pxm_to_vm_domainid(int pxm)
705 {
706 
707 	return (-1);
708 }
709 
710 #endif /* MAXMEMDOM > 1 */
711