This source file includes following definitions.
- find_mem_initiator
- find_mem_target
- alloc_memory_initiator
- alloc_memory_target
- hmat_data_type
- hmat_data_type_suffix
- hmat_normalize
- hmat_update_target_access
- hmat_add_locality
- hmat_parse_locality
- hmat_parse_cache
- hmat_parse_proximity_domain
- hmat_parse_subtable
- srat_parse_mem_affinity
- hmat_initiator_perf
- hmat_update_best
- initiator_cmp
- hmat_register_target_initiators
- hmat_register_target_cache
- hmat_register_target_perf
- hmat_register_target
- hmat_register_targets
- hmat_callback
- hmat_free_structures
- hmat_init
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11 #include <linux/acpi.h>
12 #include <linux/bitops.h>
13 #include <linux/device.h>
14 #include <linux/init.h>
15 #include <linux/list.h>
16 #include <linux/list_sort.h>
17 #include <linux/memory.h>
18 #include <linux/mutex.h>
19 #include <linux/node.h>
20 #include <linux/sysfs.h>
21
22 static u8 hmat_revision;
23
24 static LIST_HEAD(targets);
25 static LIST_HEAD(initiators);
26 static LIST_HEAD(localities);
27
28 static DEFINE_MUTEX(target_lock);
29
30
31
32
33
34 enum locality_types {
35 WRITE_LATENCY,
36 READ_LATENCY,
37 WRITE_BANDWIDTH,
38 READ_BANDWIDTH,
39 };
40
41 static struct memory_locality *localities_types[4];
42
43 struct target_cache {
44 struct list_head node;
45 struct node_cache_attrs cache_attrs;
46 };
47
48 struct memory_target {
49 struct list_head node;
50 unsigned int memory_pxm;
51 unsigned int processor_pxm;
52 struct node_hmem_attrs hmem_attrs;
53 struct list_head caches;
54 struct node_cache_attrs cache_attrs;
55 bool registered;
56 };
57
58 struct memory_initiator {
59 struct list_head node;
60 unsigned int processor_pxm;
61 };
62
63 struct memory_locality {
64 struct list_head node;
65 struct acpi_hmat_locality *hmat_loc;
66 };
67
68 static struct memory_initiator *find_mem_initiator(unsigned int cpu_pxm)
69 {
70 struct memory_initiator *initiator;
71
72 list_for_each_entry(initiator, &initiators, node)
73 if (initiator->processor_pxm == cpu_pxm)
74 return initiator;
75 return NULL;
76 }
77
78 static struct memory_target *find_mem_target(unsigned int mem_pxm)
79 {
80 struct memory_target *target;
81
82 list_for_each_entry(target, &targets, node)
83 if (target->memory_pxm == mem_pxm)
84 return target;
85 return NULL;
86 }
87
88 static __init void alloc_memory_initiator(unsigned int cpu_pxm)
89 {
90 struct memory_initiator *initiator;
91
92 if (pxm_to_node(cpu_pxm) == NUMA_NO_NODE)
93 return;
94
95 initiator = find_mem_initiator(cpu_pxm);
96 if (initiator)
97 return;
98
99 initiator = kzalloc(sizeof(*initiator), GFP_KERNEL);
100 if (!initiator)
101 return;
102
103 initiator->processor_pxm = cpu_pxm;
104 list_add_tail(&initiator->node, &initiators);
105 }
106
107 static __init void alloc_memory_target(unsigned int mem_pxm)
108 {
109 struct memory_target *target;
110
111 target = find_mem_target(mem_pxm);
112 if (target)
113 return;
114
115 target = kzalloc(sizeof(*target), GFP_KERNEL);
116 if (!target)
117 return;
118
119 target->memory_pxm = mem_pxm;
120 target->processor_pxm = PXM_INVAL;
121 list_add_tail(&target->node, &targets);
122 INIT_LIST_HEAD(&target->caches);
123 }
124
125 static __init const char *hmat_data_type(u8 type)
126 {
127 switch (type) {
128 case ACPI_HMAT_ACCESS_LATENCY:
129 return "Access Latency";
130 case ACPI_HMAT_READ_LATENCY:
131 return "Read Latency";
132 case ACPI_HMAT_WRITE_LATENCY:
133 return "Write Latency";
134 case ACPI_HMAT_ACCESS_BANDWIDTH:
135 return "Access Bandwidth";
136 case ACPI_HMAT_READ_BANDWIDTH:
137 return "Read Bandwidth";
138 case ACPI_HMAT_WRITE_BANDWIDTH:
139 return "Write Bandwidth";
140 default:
141 return "Reserved";
142 }
143 }
144
145 static __init const char *hmat_data_type_suffix(u8 type)
146 {
147 switch (type) {
148 case ACPI_HMAT_ACCESS_LATENCY:
149 case ACPI_HMAT_READ_LATENCY:
150 case ACPI_HMAT_WRITE_LATENCY:
151 return " nsec";
152 case ACPI_HMAT_ACCESS_BANDWIDTH:
153 case ACPI_HMAT_READ_BANDWIDTH:
154 case ACPI_HMAT_WRITE_BANDWIDTH:
155 return " MB/s";
156 default:
157 return "";
158 }
159 }
160
161 static u32 hmat_normalize(u16 entry, u64 base, u8 type)
162 {
163 u32 value;
164
165
166
167
168 if (entry == 0xffff || !entry)
169 return 0;
170 else if (base > (UINT_MAX / (entry)))
171 return 0;
172
173
174
175
176
177 value = entry * base;
178 if (hmat_revision == 1) {
179 if (value < 10)
180 return 0;
181 value = DIV_ROUND_UP(value, 10);
182 } else if (hmat_revision == 2) {
183 switch (type) {
184 case ACPI_HMAT_ACCESS_LATENCY:
185 case ACPI_HMAT_READ_LATENCY:
186 case ACPI_HMAT_WRITE_LATENCY:
187 value = DIV_ROUND_UP(value, 1000);
188 break;
189 default:
190 break;
191 }
192 }
193 return value;
194 }
195
196 static void hmat_update_target_access(struct memory_target *target,
197 u8 type, u32 value)
198 {
199 switch (type) {
200 case ACPI_HMAT_ACCESS_LATENCY:
201 target->hmem_attrs.read_latency = value;
202 target->hmem_attrs.write_latency = value;
203 break;
204 case ACPI_HMAT_READ_LATENCY:
205 target->hmem_attrs.read_latency = value;
206 break;
207 case ACPI_HMAT_WRITE_LATENCY:
208 target->hmem_attrs.write_latency = value;
209 break;
210 case ACPI_HMAT_ACCESS_BANDWIDTH:
211 target->hmem_attrs.read_bandwidth = value;
212 target->hmem_attrs.write_bandwidth = value;
213 break;
214 case ACPI_HMAT_READ_BANDWIDTH:
215 target->hmem_attrs.read_bandwidth = value;
216 break;
217 case ACPI_HMAT_WRITE_BANDWIDTH:
218 target->hmem_attrs.write_bandwidth = value;
219 break;
220 default:
221 break;
222 }
223 }
224
225 static __init void hmat_add_locality(struct acpi_hmat_locality *hmat_loc)
226 {
227 struct memory_locality *loc;
228
229 loc = kzalloc(sizeof(*loc), GFP_KERNEL);
230 if (!loc) {
231 pr_notice_once("Failed to allocate HMAT locality\n");
232 return;
233 }
234
235 loc->hmat_loc = hmat_loc;
236 list_add_tail(&loc->node, &localities);
237
238 switch (hmat_loc->data_type) {
239 case ACPI_HMAT_ACCESS_LATENCY:
240 localities_types[READ_LATENCY] = loc;
241 localities_types[WRITE_LATENCY] = loc;
242 break;
243 case ACPI_HMAT_READ_LATENCY:
244 localities_types[READ_LATENCY] = loc;
245 break;
246 case ACPI_HMAT_WRITE_LATENCY:
247 localities_types[WRITE_LATENCY] = loc;
248 break;
249 case ACPI_HMAT_ACCESS_BANDWIDTH:
250 localities_types[READ_BANDWIDTH] = loc;
251 localities_types[WRITE_BANDWIDTH] = loc;
252 break;
253 case ACPI_HMAT_READ_BANDWIDTH:
254 localities_types[READ_BANDWIDTH] = loc;
255 break;
256 case ACPI_HMAT_WRITE_BANDWIDTH:
257 localities_types[WRITE_BANDWIDTH] = loc;
258 break;
259 default:
260 break;
261 }
262 }
263
264 static __init int hmat_parse_locality(union acpi_subtable_headers *header,
265 const unsigned long end)
266 {
267 struct acpi_hmat_locality *hmat_loc = (void *)header;
268 struct memory_target *target;
269 unsigned int init, targ, total_size, ipds, tpds;
270 u32 *inits, *targs, value;
271 u16 *entries;
272 u8 type, mem_hier;
273
274 if (hmat_loc->header.length < sizeof(*hmat_loc)) {
275 pr_notice("HMAT: Unexpected locality header length: %d\n",
276 hmat_loc->header.length);
277 return -EINVAL;
278 }
279
280 type = hmat_loc->data_type;
281 mem_hier = hmat_loc->flags & ACPI_HMAT_MEMORY_HIERARCHY;
282 ipds = hmat_loc->number_of_initiator_Pds;
283 tpds = hmat_loc->number_of_target_Pds;
284 total_size = sizeof(*hmat_loc) + sizeof(*entries) * ipds * tpds +
285 sizeof(*inits) * ipds + sizeof(*targs) * tpds;
286 if (hmat_loc->header.length < total_size) {
287 pr_notice("HMAT: Unexpected locality header length:%d, minimum required:%d\n",
288 hmat_loc->header.length, total_size);
289 return -EINVAL;
290 }
291
292 pr_info("HMAT: Locality: Flags:%02x Type:%s Initiator Domains:%d Target Domains:%d Base:%lld\n",
293 hmat_loc->flags, hmat_data_type(type), ipds, tpds,
294 hmat_loc->entry_base_unit);
295
296 inits = (u32 *)(hmat_loc + 1);
297 targs = inits + ipds;
298 entries = (u16 *)(targs + tpds);
299 for (init = 0; init < ipds; init++) {
300 alloc_memory_initiator(inits[init]);
301 for (targ = 0; targ < tpds; targ++) {
302 value = hmat_normalize(entries[init * tpds + targ],
303 hmat_loc->entry_base_unit,
304 type);
305 pr_info(" Initiator-Target[%d-%d]:%d%s\n",
306 inits[init], targs[targ], value,
307 hmat_data_type_suffix(type));
308
309 if (mem_hier == ACPI_HMAT_MEMORY) {
310 target = find_mem_target(targs[targ]);
311 if (target && target->processor_pxm == inits[init])
312 hmat_update_target_access(target, type, value);
313 }
314 }
315 }
316
317 if (mem_hier == ACPI_HMAT_MEMORY)
318 hmat_add_locality(hmat_loc);
319
320 return 0;
321 }
322
323 static __init int hmat_parse_cache(union acpi_subtable_headers *header,
324 const unsigned long end)
325 {
326 struct acpi_hmat_cache *cache = (void *)header;
327 struct memory_target *target;
328 struct target_cache *tcache;
329 u32 attrs;
330
331 if (cache->header.length < sizeof(*cache)) {
332 pr_notice("HMAT: Unexpected cache header length: %d\n",
333 cache->header.length);
334 return -EINVAL;
335 }
336
337 attrs = cache->cache_attributes;
338 pr_info("HMAT: Cache: Domain:%d Size:%llu Attrs:%08x SMBIOS Handles:%d\n",
339 cache->memory_PD, cache->cache_size, attrs,
340 cache->number_of_SMBIOShandles);
341
342 target = find_mem_target(cache->memory_PD);
343 if (!target)
344 return 0;
345
346 tcache = kzalloc(sizeof(*tcache), GFP_KERNEL);
347 if (!tcache) {
348 pr_notice_once("Failed to allocate HMAT cache info\n");
349 return 0;
350 }
351
352 tcache->cache_attrs.size = cache->cache_size;
353 tcache->cache_attrs.level = (attrs & ACPI_HMAT_CACHE_LEVEL) >> 4;
354 tcache->cache_attrs.line_size = (attrs & ACPI_HMAT_CACHE_LINE_SIZE) >> 16;
355
356 switch ((attrs & ACPI_HMAT_CACHE_ASSOCIATIVITY) >> 8) {
357 case ACPI_HMAT_CA_DIRECT_MAPPED:
358 tcache->cache_attrs.indexing = NODE_CACHE_DIRECT_MAP;
359 break;
360 case ACPI_HMAT_CA_COMPLEX_CACHE_INDEXING:
361 tcache->cache_attrs.indexing = NODE_CACHE_INDEXED;
362 break;
363 case ACPI_HMAT_CA_NONE:
364 default:
365 tcache->cache_attrs.indexing = NODE_CACHE_OTHER;
366 break;
367 }
368
369 switch ((attrs & ACPI_HMAT_WRITE_POLICY) >> 12) {
370 case ACPI_HMAT_CP_WB:
371 tcache->cache_attrs.write_policy = NODE_CACHE_WRITE_BACK;
372 break;
373 case ACPI_HMAT_CP_WT:
374 tcache->cache_attrs.write_policy = NODE_CACHE_WRITE_THROUGH;
375 break;
376 case ACPI_HMAT_CP_NONE:
377 default:
378 tcache->cache_attrs.write_policy = NODE_CACHE_WRITE_OTHER;
379 break;
380 }
381 list_add_tail(&tcache->node, &target->caches);
382
383 return 0;
384 }
385
386 static int __init hmat_parse_proximity_domain(union acpi_subtable_headers *header,
387 const unsigned long end)
388 {
389 struct acpi_hmat_proximity_domain *p = (void *)header;
390 struct memory_target *target = NULL;
391
392 if (p->header.length != sizeof(*p)) {
393 pr_notice("HMAT: Unexpected address range header length: %d\n",
394 p->header.length);
395 return -EINVAL;
396 }
397
398 if (hmat_revision == 1)
399 pr_info("HMAT: Memory (%#llx length %#llx) Flags:%04x Processor Domain:%d Memory Domain:%d\n",
400 p->reserved3, p->reserved4, p->flags, p->processor_PD,
401 p->memory_PD);
402 else
403 pr_info("HMAT: Memory Flags:%04x Processor Domain:%d Memory Domain:%d\n",
404 p->flags, p->processor_PD, p->memory_PD);
405
406 if (p->flags & ACPI_HMAT_MEMORY_PD_VALID && hmat_revision == 1) {
407 target = find_mem_target(p->memory_PD);
408 if (!target) {
409 pr_debug("HMAT: Memory Domain missing from SRAT\n");
410 return -EINVAL;
411 }
412 }
413 if (target && p->flags & ACPI_HMAT_PROCESSOR_PD_VALID) {
414 int p_node = pxm_to_node(p->processor_PD);
415
416 if (p_node == NUMA_NO_NODE) {
417 pr_debug("HMAT: Invalid Processor Domain\n");
418 return -EINVAL;
419 }
420 target->processor_pxm = p_node;
421 }
422
423 return 0;
424 }
425
426 static int __init hmat_parse_subtable(union acpi_subtable_headers *header,
427 const unsigned long end)
428 {
429 struct acpi_hmat_structure *hdr = (void *)header;
430
431 if (!hdr)
432 return -EINVAL;
433
434 switch (hdr->type) {
435 case ACPI_HMAT_TYPE_PROXIMITY:
436 return hmat_parse_proximity_domain(header, end);
437 case ACPI_HMAT_TYPE_LOCALITY:
438 return hmat_parse_locality(header, end);
439 case ACPI_HMAT_TYPE_CACHE:
440 return hmat_parse_cache(header, end);
441 default:
442 return -EINVAL;
443 }
444 }
445
446 static __init int srat_parse_mem_affinity(union acpi_subtable_headers *header,
447 const unsigned long end)
448 {
449 struct acpi_srat_mem_affinity *ma = (void *)header;
450
451 if (!ma)
452 return -EINVAL;
453 if (!(ma->flags & ACPI_SRAT_MEM_ENABLED))
454 return 0;
455 alloc_memory_target(ma->proximity_domain);
456 return 0;
457 }
458
459 static u32 hmat_initiator_perf(struct memory_target *target,
460 struct memory_initiator *initiator,
461 struct acpi_hmat_locality *hmat_loc)
462 {
463 unsigned int ipds, tpds, i, idx = 0, tdx = 0;
464 u32 *inits, *targs;
465 u16 *entries;
466
467 ipds = hmat_loc->number_of_initiator_Pds;
468 tpds = hmat_loc->number_of_target_Pds;
469 inits = (u32 *)(hmat_loc + 1);
470 targs = inits + ipds;
471 entries = (u16 *)(targs + tpds);
472
473 for (i = 0; i < ipds; i++) {
474 if (inits[i] == initiator->processor_pxm) {
475 idx = i;
476 break;
477 }
478 }
479
480 if (i == ipds)
481 return 0;
482
483 for (i = 0; i < tpds; i++) {
484 if (targs[i] == target->memory_pxm) {
485 tdx = i;
486 break;
487 }
488 }
489 if (i == tpds)
490 return 0;
491
492 return hmat_normalize(entries[idx * tpds + tdx],
493 hmat_loc->entry_base_unit,
494 hmat_loc->data_type);
495 }
496
497 static bool hmat_update_best(u8 type, u32 value, u32 *best)
498 {
499 bool updated = false;
500
501 if (!value)
502 return false;
503
504 switch (type) {
505 case ACPI_HMAT_ACCESS_LATENCY:
506 case ACPI_HMAT_READ_LATENCY:
507 case ACPI_HMAT_WRITE_LATENCY:
508 if (!*best || *best > value) {
509 *best = value;
510 updated = true;
511 }
512 break;
513 case ACPI_HMAT_ACCESS_BANDWIDTH:
514 case ACPI_HMAT_READ_BANDWIDTH:
515 case ACPI_HMAT_WRITE_BANDWIDTH:
516 if (!*best || *best < value) {
517 *best = value;
518 updated = true;
519 }
520 break;
521 }
522
523 return updated;
524 }
525
526 static int initiator_cmp(void *priv, struct list_head *a, struct list_head *b)
527 {
528 struct memory_initiator *ia;
529 struct memory_initiator *ib;
530 unsigned long *p_nodes = priv;
531
532 ia = list_entry(a, struct memory_initiator, node);
533 ib = list_entry(b, struct memory_initiator, node);
534
535 set_bit(ia->processor_pxm, p_nodes);
536 set_bit(ib->processor_pxm, p_nodes);
537
538 return ia->processor_pxm - ib->processor_pxm;
539 }
540
541 static void hmat_register_target_initiators(struct memory_target *target)
542 {
543 static DECLARE_BITMAP(p_nodes, MAX_NUMNODES);
544 struct memory_initiator *initiator;
545 unsigned int mem_nid, cpu_nid;
546 struct memory_locality *loc = NULL;
547 u32 best = 0;
548 int i;
549
550 mem_nid = pxm_to_node(target->memory_pxm);
551
552
553
554
555
556 if (target->processor_pxm != PXM_INVAL) {
557 cpu_nid = pxm_to_node(target->processor_pxm);
558 register_memory_node_under_compute_node(mem_nid, cpu_nid, 0);
559 return;
560 }
561
562 if (list_empty(&localities))
563 return;
564
565
566
567
568
569
570
571 bitmap_zero(p_nodes, MAX_NUMNODES);
572 list_sort(p_nodes, &initiators, initiator_cmp);
573 for (i = WRITE_LATENCY; i <= READ_BANDWIDTH; i++) {
574 loc = localities_types[i];
575 if (!loc)
576 continue;
577
578 best = 0;
579 list_for_each_entry(initiator, &initiators, node) {
580 u32 value;
581
582 if (!test_bit(initiator->processor_pxm, p_nodes))
583 continue;
584
585 value = hmat_initiator_perf(target, initiator, loc->hmat_loc);
586 if (hmat_update_best(loc->hmat_loc->data_type, value, &best))
587 bitmap_clear(p_nodes, 0, initiator->processor_pxm);
588 if (value != best)
589 clear_bit(initiator->processor_pxm, p_nodes);
590 }
591 if (best)
592 hmat_update_target_access(target, loc->hmat_loc->data_type, best);
593 }
594
595 for_each_set_bit(i, p_nodes, MAX_NUMNODES) {
596 cpu_nid = pxm_to_node(i);
597 register_memory_node_under_compute_node(mem_nid, cpu_nid, 0);
598 }
599 }
600
601 static void hmat_register_target_cache(struct memory_target *target)
602 {
603 unsigned mem_nid = pxm_to_node(target->memory_pxm);
604 struct target_cache *tcache;
605
606 list_for_each_entry(tcache, &target->caches, node)
607 node_add_cache(mem_nid, &tcache->cache_attrs);
608 }
609
610 static void hmat_register_target_perf(struct memory_target *target)
611 {
612 unsigned mem_nid = pxm_to_node(target->memory_pxm);
613 node_set_perf_attrs(mem_nid, &target->hmem_attrs, 0);
614 }
615
616 static void hmat_register_target(struct memory_target *target)
617 {
618 int nid = pxm_to_node(target->memory_pxm);
619
620
621
622
623
624
625
626
627 if (nid == NUMA_NO_NODE || !node_online(nid))
628 return;
629
630 mutex_lock(&target_lock);
631 if (!target->registered) {
632 hmat_register_target_initiators(target);
633 hmat_register_target_cache(target);
634 hmat_register_target_perf(target);
635 target->registered = true;
636 }
637 mutex_unlock(&target_lock);
638 }
639
640 static void hmat_register_targets(void)
641 {
642 struct memory_target *target;
643
644 list_for_each_entry(target, &targets, node)
645 hmat_register_target(target);
646 }
647
648 static int hmat_callback(struct notifier_block *self,
649 unsigned long action, void *arg)
650 {
651 struct memory_target *target;
652 struct memory_notify *mnb = arg;
653 int pxm, nid = mnb->status_change_nid;
654
655 if (nid == NUMA_NO_NODE || action != MEM_ONLINE)
656 return NOTIFY_OK;
657
658 pxm = node_to_pxm(nid);
659 target = find_mem_target(pxm);
660 if (!target)
661 return NOTIFY_OK;
662
663 hmat_register_target(target);
664 return NOTIFY_OK;
665 }
666
667 static struct notifier_block hmat_callback_nb = {
668 .notifier_call = hmat_callback,
669 .priority = 2,
670 };
671
672 static __init void hmat_free_structures(void)
673 {
674 struct memory_target *target, *tnext;
675 struct memory_locality *loc, *lnext;
676 struct memory_initiator *initiator, *inext;
677 struct target_cache *tcache, *cnext;
678
679 list_for_each_entry_safe(target, tnext, &targets, node) {
680 list_for_each_entry_safe(tcache, cnext, &target->caches, node) {
681 list_del(&tcache->node);
682 kfree(tcache);
683 }
684 list_del(&target->node);
685 kfree(target);
686 }
687
688 list_for_each_entry_safe(initiator, inext, &initiators, node) {
689 list_del(&initiator->node);
690 kfree(initiator);
691 }
692
693 list_for_each_entry_safe(loc, lnext, &localities, node) {
694 list_del(&loc->node);
695 kfree(loc);
696 }
697 }
698
699 static __init int hmat_init(void)
700 {
701 struct acpi_table_header *tbl;
702 enum acpi_hmat_type i;
703 acpi_status status;
704
705 if (srat_disabled())
706 return 0;
707
708 status = acpi_get_table(ACPI_SIG_SRAT, 0, &tbl);
709 if (ACPI_FAILURE(status))
710 return 0;
711
712 if (acpi_table_parse_entries(ACPI_SIG_SRAT,
713 sizeof(struct acpi_table_srat),
714 ACPI_SRAT_TYPE_MEMORY_AFFINITY,
715 srat_parse_mem_affinity, 0) < 0)
716 goto out_put;
717 acpi_put_table(tbl);
718
719 status = acpi_get_table(ACPI_SIG_HMAT, 0, &tbl);
720 if (ACPI_FAILURE(status))
721 goto out_put;
722
723 hmat_revision = tbl->revision;
724 switch (hmat_revision) {
725 case 1:
726 case 2:
727 break;
728 default:
729 pr_notice("Ignoring HMAT: Unknown revision:%d\n", hmat_revision);
730 goto out_put;
731 }
732
733 for (i = ACPI_HMAT_TYPE_PROXIMITY; i < ACPI_HMAT_TYPE_RESERVED; i++) {
734 if (acpi_table_parse_entries(ACPI_SIG_HMAT,
735 sizeof(struct acpi_table_hmat), i,
736 hmat_parse_subtable, 0) < 0) {
737 pr_notice("Ignoring HMAT: Invalid table");
738 goto out_put;
739 }
740 }
741 hmat_register_targets();
742
743
744 if (!register_hotmemory_notifier(&hmat_callback_nb))
745 return 0;
746 out_put:
747 hmat_free_structures();
748 acpi_put_table(tbl);
749 return 0;
750 }
751 subsys_initcall(hmat_init);