1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Basic Node interface support
4 */
5
6 #include <linux/module.h>
7 #include <linux/init.h>
8 #include <linux/mm.h>
9 #include <linux/memory.h>
10 #include <linux/vmstat.h>
11 #include <linux/notifier.h>
12 #include <linux/node.h>
13 #include <linux/hugetlb.h>
14 #include <linux/compaction.h>
15 #include <linux/cpumask.h>
16 #include <linux/topology.h>
17 #include <linux/nodemask.h>
18 #include <linux/cpu.h>
19 #include <linux/device.h>
20 #include <linux/pm_runtime.h>
21 #include <linux/swap.h>
22 #include <linux/slab.h>
23
24 static struct bus_type node_subsys = {
25 .name = "node",
26 .dev_name = "node",
27 };
28
29
node_read_cpumap(struct device * dev,bool list,char * buf)30 static ssize_t node_read_cpumap(struct device *dev, bool list, char *buf)
31 {
32 ssize_t n;
33 cpumask_var_t mask;
34 struct node *node_dev = to_node(dev);
35
36 /* 2008/04/07: buf currently PAGE_SIZE, need 9 chars per 32 bits. */
37 BUILD_BUG_ON((NR_CPUS/32 * 9) > (PAGE_SIZE-1));
38
39 if (!alloc_cpumask_var(&mask, GFP_KERNEL))
40 return 0;
41
42 cpumask_and(mask, cpumask_of_node(node_dev->dev.id), cpu_online_mask);
43 n = cpumap_print_to_pagebuf(list, buf, mask);
44 free_cpumask_var(mask);
45
46 return n;
47 }
48
cpumap_show(struct device * dev,struct device_attribute * attr,char * buf)49 static inline ssize_t cpumap_show(struct device *dev,
50 struct device_attribute *attr,
51 char *buf)
52 {
53 return node_read_cpumap(dev, false, buf);
54 }
55
56 static DEVICE_ATTR_RO(cpumap);
57
cpulist_show(struct device * dev,struct device_attribute * attr,char * buf)58 static inline ssize_t cpulist_show(struct device *dev,
59 struct device_attribute *attr,
60 char *buf)
61 {
62 return node_read_cpumap(dev, true, buf);
63 }
64
65 static DEVICE_ATTR_RO(cpulist);
66
67 /**
68 * struct node_access_nodes - Access class device to hold user visible
69 * relationships to other nodes.
70 * @dev: Device for this memory access class
71 * @list_node: List element in the node's access list
72 * @access: The access class rank
73 * @hmem_attrs: Heterogeneous memory performance attributes
74 */
75 struct node_access_nodes {
76 struct device dev;
77 struct list_head list_node;
78 unsigned access;
79 #ifdef CONFIG_HMEM_REPORTING
80 struct node_hmem_attrs hmem_attrs;
81 #endif
82 };
83 #define to_access_nodes(dev) container_of(dev, struct node_access_nodes, dev)
84
85 static struct attribute *node_init_access_node_attrs[] = {
86 NULL,
87 };
88
89 static struct attribute *node_targ_access_node_attrs[] = {
90 NULL,
91 };
92
93 static const struct attribute_group initiators = {
94 .name = "initiators",
95 .attrs = node_init_access_node_attrs,
96 };
97
98 static const struct attribute_group targets = {
99 .name = "targets",
100 .attrs = node_targ_access_node_attrs,
101 };
102
103 static const struct attribute_group *node_access_node_groups[] = {
104 &initiators,
105 &targets,
106 NULL,
107 };
108
node_remove_accesses(struct node * node)109 static void node_remove_accesses(struct node *node)
110 {
111 struct node_access_nodes *c, *cnext;
112
113 list_for_each_entry_safe(c, cnext, &node->access_list, list_node) {
114 list_del(&c->list_node);
115 device_unregister(&c->dev);
116 }
117 }
118
node_access_release(struct device * dev)119 static void node_access_release(struct device *dev)
120 {
121 kfree(to_access_nodes(dev));
122 }
123
node_init_node_access(struct node * node,unsigned access)124 static struct node_access_nodes *node_init_node_access(struct node *node,
125 unsigned access)
126 {
127 struct node_access_nodes *access_node;
128 struct device *dev;
129
130 list_for_each_entry(access_node, &node->access_list, list_node)
131 if (access_node->access == access)
132 return access_node;
133
134 access_node = kzalloc(sizeof(*access_node), GFP_KERNEL);
135 if (!access_node)
136 return NULL;
137
138 access_node->access = access;
139 dev = &access_node->dev;
140 dev->parent = &node->dev;
141 dev->release = node_access_release;
142 dev->groups = node_access_node_groups;
143 if (dev_set_name(dev, "access%u", access))
144 goto free;
145
146 if (device_register(dev))
147 goto free_name;
148
149 pm_runtime_no_callbacks(dev);
150 list_add_tail(&access_node->list_node, &node->access_list);
151 return access_node;
152 free_name:
153 kfree_const(dev->kobj.name);
154 free:
155 kfree(access_node);
156 return NULL;
157 }
158
159 #ifdef CONFIG_HMEM_REPORTING
160 #define ACCESS_ATTR(name) \
161 static ssize_t name##_show(struct device *dev, \
162 struct device_attribute *attr, \
163 char *buf) \
164 { \
165 return sysfs_emit(buf, "%u\n", \
166 to_access_nodes(dev)->hmem_attrs.name); \
167 } \
168 static DEVICE_ATTR_RO(name)
169
170 ACCESS_ATTR(read_bandwidth);
171 ACCESS_ATTR(read_latency);
172 ACCESS_ATTR(write_bandwidth);
173 ACCESS_ATTR(write_latency);
174
175 static struct attribute *access_attrs[] = {
176 &dev_attr_read_bandwidth.attr,
177 &dev_attr_read_latency.attr,
178 &dev_attr_write_bandwidth.attr,
179 &dev_attr_write_latency.attr,
180 NULL,
181 };
182
183 /**
184 * node_set_perf_attrs - Set the performance values for given access class
185 * @nid: Node identifier to be set
186 * @hmem_attrs: Heterogeneous memory performance attributes
187 * @access: The access class the for the given attributes
188 */
node_set_perf_attrs(unsigned int nid,struct node_hmem_attrs * hmem_attrs,unsigned access)189 void node_set_perf_attrs(unsigned int nid, struct node_hmem_attrs *hmem_attrs,
190 unsigned access)
191 {
192 struct node_access_nodes *c;
193 struct node *node;
194 int i;
195
196 if (WARN_ON_ONCE(!node_online(nid)))
197 return;
198
199 node = node_devices[nid];
200 c = node_init_node_access(node, access);
201 if (!c)
202 return;
203
204 c->hmem_attrs = *hmem_attrs;
205 for (i = 0; access_attrs[i] != NULL; i++) {
206 if (sysfs_add_file_to_group(&c->dev.kobj, access_attrs[i],
207 "initiators")) {
208 pr_info("failed to add performance attribute to node %d\n",
209 nid);
210 break;
211 }
212 }
213 }
214
215 /**
216 * struct node_cache_info - Internal tracking for memory node caches
217 * @dev: Device represeting the cache level
218 * @node: List element for tracking in the node
219 * @cache_attrs:Attributes for this cache level
220 */
221 struct node_cache_info {
222 struct device dev;
223 struct list_head node;
224 struct node_cache_attrs cache_attrs;
225 };
226 #define to_cache_info(device) container_of(device, struct node_cache_info, dev)
227
228 #define CACHE_ATTR(name, fmt) \
229 static ssize_t name##_show(struct device *dev, \
230 struct device_attribute *attr, \
231 char *buf) \
232 { \
233 return sysfs_emit(buf, fmt "\n", \
234 to_cache_info(dev)->cache_attrs.name); \
235 } \
236 DEVICE_ATTR_RO(name);
237
238 CACHE_ATTR(size, "%llu")
239 CACHE_ATTR(line_size, "%u")
240 CACHE_ATTR(indexing, "%u")
241 CACHE_ATTR(write_policy, "%u")
242
243 static struct attribute *cache_attrs[] = {
244 &dev_attr_indexing.attr,
245 &dev_attr_size.attr,
246 &dev_attr_line_size.attr,
247 &dev_attr_write_policy.attr,
248 NULL,
249 };
250 ATTRIBUTE_GROUPS(cache);
251
node_cache_release(struct device * dev)252 static void node_cache_release(struct device *dev)
253 {
254 kfree(dev);
255 }
256
node_cacheinfo_release(struct device * dev)257 static void node_cacheinfo_release(struct device *dev)
258 {
259 struct node_cache_info *info = to_cache_info(dev);
260 kfree(info);
261 }
262
node_init_cache_dev(struct node * node)263 static void node_init_cache_dev(struct node *node)
264 {
265 struct device *dev;
266
267 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
268 if (!dev)
269 return;
270
271 device_initialize(dev);
272 dev->parent = &node->dev;
273 dev->release = node_cache_release;
274 if (dev_set_name(dev, "memory_side_cache"))
275 goto put_device;
276
277 if (device_add(dev))
278 goto put_device;
279
280 pm_runtime_no_callbacks(dev);
281 node->cache_dev = dev;
282 return;
283 put_device:
284 put_device(dev);
285 }
286
287 /**
288 * node_add_cache() - add cache attribute to a memory node
289 * @nid: Node identifier that has new cache attributes
290 * @cache_attrs: Attributes for the cache being added
291 */
node_add_cache(unsigned int nid,struct node_cache_attrs * cache_attrs)292 void node_add_cache(unsigned int nid, struct node_cache_attrs *cache_attrs)
293 {
294 struct node_cache_info *info;
295 struct device *dev;
296 struct node *node;
297
298 if (!node_online(nid) || !node_devices[nid])
299 return;
300
301 node = node_devices[nid];
302 list_for_each_entry(info, &node->cache_attrs, node) {
303 if (info->cache_attrs.level == cache_attrs->level) {
304 dev_warn(&node->dev,
305 "attempt to add duplicate cache level:%d\n",
306 cache_attrs->level);
307 return;
308 }
309 }
310
311 if (!node->cache_dev)
312 node_init_cache_dev(node);
313 if (!node->cache_dev)
314 return;
315
316 info = kzalloc(sizeof(*info), GFP_KERNEL);
317 if (!info)
318 return;
319
320 dev = &info->dev;
321 device_initialize(dev);
322 dev->parent = node->cache_dev;
323 dev->release = node_cacheinfo_release;
324 dev->groups = cache_groups;
325 if (dev_set_name(dev, "index%d", cache_attrs->level))
326 goto put_device;
327
328 info->cache_attrs = *cache_attrs;
329 if (device_add(dev)) {
330 dev_warn(&node->dev, "failed to add cache level:%d\n",
331 cache_attrs->level);
332 goto put_device;
333 }
334 pm_runtime_no_callbacks(dev);
335 list_add_tail(&info->node, &node->cache_attrs);
336 return;
337 put_device:
338 put_device(dev);
339 }
340
node_remove_caches(struct node * node)341 static void node_remove_caches(struct node *node)
342 {
343 struct node_cache_info *info, *next;
344
345 if (!node->cache_dev)
346 return;
347
348 list_for_each_entry_safe(info, next, &node->cache_attrs, node) {
349 list_del(&info->node);
350 device_unregister(&info->dev);
351 }
352 device_unregister(node->cache_dev);
353 }
354
node_init_caches(unsigned int nid)355 static void node_init_caches(unsigned int nid)
356 {
357 INIT_LIST_HEAD(&node_devices[nid]->cache_attrs);
358 }
359 #else
node_init_caches(unsigned int nid)360 static void node_init_caches(unsigned int nid) { }
node_remove_caches(struct node * node)361 static void node_remove_caches(struct node *node) { }
362 #endif
363
364 #define K(x) ((x) << (PAGE_SHIFT - 10))
node_read_meminfo(struct device * dev,struct device_attribute * attr,char * buf)365 static ssize_t node_read_meminfo(struct device *dev,
366 struct device_attribute *attr, char *buf)
367 {
368 int len = 0;
369 int nid = dev->id;
370 struct pglist_data *pgdat = NODE_DATA(nid);
371 struct sysinfo i;
372 unsigned long sreclaimable, sunreclaimable;
373 unsigned long swapcached = 0;
374
375 si_meminfo_node(&i, nid);
376 sreclaimable = node_page_state_pages(pgdat, NR_SLAB_RECLAIMABLE_B);
377 sunreclaimable = node_page_state_pages(pgdat, NR_SLAB_UNRECLAIMABLE_B);
378 #ifdef CONFIG_SWAP
379 swapcached = node_page_state_pages(pgdat, NR_SWAPCACHE);
380 #endif
381 len = sysfs_emit_at(buf, len,
382 "Node %d MemTotal: %8lu kB\n"
383 "Node %d MemFree: %8lu kB\n"
384 "Node %d MemUsed: %8lu kB\n"
385 "Node %d SwapCached: %8lu kB\n"
386 "Node %d Active: %8lu kB\n"
387 "Node %d Inactive: %8lu kB\n"
388 "Node %d Active(anon): %8lu kB\n"
389 "Node %d Inactive(anon): %8lu kB\n"
390 "Node %d Active(file): %8lu kB\n"
391 "Node %d Inactive(file): %8lu kB\n"
392 "Node %d Unevictable: %8lu kB\n"
393 "Node %d Mlocked: %8lu kB\n",
394 nid, K(i.totalram),
395 nid, K(i.freeram),
396 nid, K(i.totalram - i.freeram),
397 nid, K(swapcached),
398 nid, K(node_page_state(pgdat, NR_ACTIVE_ANON) +
399 node_page_state(pgdat, NR_ACTIVE_FILE)),
400 nid, K(node_page_state(pgdat, NR_INACTIVE_ANON) +
401 node_page_state(pgdat, NR_INACTIVE_FILE)),
402 nid, K(node_page_state(pgdat, NR_ACTIVE_ANON)),
403 nid, K(node_page_state(pgdat, NR_INACTIVE_ANON)),
404 nid, K(node_page_state(pgdat, NR_ACTIVE_FILE)),
405 nid, K(node_page_state(pgdat, NR_INACTIVE_FILE)),
406 nid, K(node_page_state(pgdat, NR_UNEVICTABLE)),
407 nid, K(sum_zone_node_page_state(nid, NR_MLOCK)));
408
409 #ifdef CONFIG_HIGHMEM
410 len += sysfs_emit_at(buf, len,
411 "Node %d HighTotal: %8lu kB\n"
412 "Node %d HighFree: %8lu kB\n"
413 "Node %d LowTotal: %8lu kB\n"
414 "Node %d LowFree: %8lu kB\n",
415 nid, K(i.totalhigh),
416 nid, K(i.freehigh),
417 nid, K(i.totalram - i.totalhigh),
418 nid, K(i.freeram - i.freehigh));
419 #endif
420 len += sysfs_emit_at(buf, len,
421 "Node %d Dirty: %8lu kB\n"
422 "Node %d Writeback: %8lu kB\n"
423 "Node %d FilePages: %8lu kB\n"
424 "Node %d Mapped: %8lu kB\n"
425 "Node %d AnonPages: %8lu kB\n"
426 "Node %d Shmem: %8lu kB\n"
427 "Node %d KernelStack: %8lu kB\n"
428 #ifdef CONFIG_SHADOW_CALL_STACK
429 "Node %d ShadowCallStack:%8lu kB\n"
430 #endif
431 "Node %d PageTables: %8lu kB\n"
432 "Node %d NFS_Unstable: %8lu kB\n"
433 "Node %d Bounce: %8lu kB\n"
434 "Node %d WritebackTmp: %8lu kB\n"
435 "Node %d KReclaimable: %8lu kB\n"
436 "Node %d Slab: %8lu kB\n"
437 "Node %d SReclaimable: %8lu kB\n"
438 "Node %d SUnreclaim: %8lu kB\n"
439 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
440 "Node %d AnonHugePages: %8lu kB\n"
441 "Node %d ShmemHugePages: %8lu kB\n"
442 "Node %d ShmemPmdMapped: %8lu kB\n"
443 "Node %d FileHugePages: %8lu kB\n"
444 "Node %d FilePmdMapped: %8lu kB\n"
445 #endif
446 ,
447 nid, K(node_page_state(pgdat, NR_FILE_DIRTY)),
448 nid, K(node_page_state(pgdat, NR_WRITEBACK)),
449 nid, K(node_page_state(pgdat, NR_FILE_PAGES)),
450 nid, K(node_page_state(pgdat, NR_FILE_MAPPED)),
451 nid, K(node_page_state(pgdat, NR_ANON_MAPPED)),
452 nid, K(i.sharedram),
453 nid, node_page_state(pgdat, NR_KERNEL_STACK_KB),
454 #ifdef CONFIG_SHADOW_CALL_STACK
455 nid, node_page_state(pgdat, NR_KERNEL_SCS_KB),
456 #endif
457 nid, K(node_page_state(pgdat, NR_PAGETABLE)),
458 nid, 0UL,
459 nid, K(sum_zone_node_page_state(nid, NR_BOUNCE)),
460 nid, K(node_page_state(pgdat, NR_WRITEBACK_TEMP)),
461 nid, K(sreclaimable +
462 node_page_state(pgdat, NR_KERNEL_MISC_RECLAIMABLE)),
463 nid, K(sreclaimable + sunreclaimable),
464 nid, K(sreclaimable),
465 nid, K(sunreclaimable)
466 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
467 ,
468 nid, K(node_page_state(pgdat, NR_ANON_THPS)),
469 nid, K(node_page_state(pgdat, NR_SHMEM_THPS)),
470 nid, K(node_page_state(pgdat, NR_SHMEM_PMDMAPPED)),
471 nid, K(node_page_state(pgdat, NR_FILE_THPS)),
472 nid, K(node_page_state(pgdat, NR_FILE_PMDMAPPED))
473 #endif
474 );
475 len += hugetlb_report_node_meminfo(buf, len, nid);
476 return len;
477 }
478
479 #undef K
480 static DEVICE_ATTR(meminfo, 0444, node_read_meminfo, NULL);
481
node_read_numastat(struct device * dev,struct device_attribute * attr,char * buf)482 static ssize_t node_read_numastat(struct device *dev,
483 struct device_attribute *attr, char *buf)
484 {
485 return sysfs_emit(buf,
486 "numa_hit %lu\n"
487 "numa_miss %lu\n"
488 "numa_foreign %lu\n"
489 "interleave_hit %lu\n"
490 "local_node %lu\n"
491 "other_node %lu\n",
492 sum_zone_numa_state(dev->id, NUMA_HIT),
493 sum_zone_numa_state(dev->id, NUMA_MISS),
494 sum_zone_numa_state(dev->id, NUMA_FOREIGN),
495 sum_zone_numa_state(dev->id, NUMA_INTERLEAVE_HIT),
496 sum_zone_numa_state(dev->id, NUMA_LOCAL),
497 sum_zone_numa_state(dev->id, NUMA_OTHER));
498 }
499 static DEVICE_ATTR(numastat, 0444, node_read_numastat, NULL);
500
node_read_vmstat(struct device * dev,struct device_attribute * attr,char * buf)501 static ssize_t node_read_vmstat(struct device *dev,
502 struct device_attribute *attr, char *buf)
503 {
504 int nid = dev->id;
505 struct pglist_data *pgdat = NODE_DATA(nid);
506 int i;
507 int len = 0;
508
509 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
510 len += sysfs_emit_at(buf, len, "%s %lu\n",
511 zone_stat_name(i),
512 sum_zone_node_page_state(nid, i));
513
514 #ifdef CONFIG_NUMA
515 for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++)
516 len += sysfs_emit_at(buf, len, "%s %lu\n",
517 numa_stat_name(i),
518 sum_zone_numa_state(nid, i));
519
520 #endif
521 for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) {
522 unsigned long pages = node_page_state_pages(pgdat, i);
523
524 if (vmstat_item_print_in_thp(i))
525 pages /= HPAGE_PMD_NR;
526 len += sysfs_emit_at(buf, len, "%s %lu\n", node_stat_name(i),
527 pages);
528 }
529
530 return len;
531 }
532 static DEVICE_ATTR(vmstat, 0444, node_read_vmstat, NULL);
533
node_read_distance(struct device * dev,struct device_attribute * attr,char * buf)534 static ssize_t node_read_distance(struct device *dev,
535 struct device_attribute *attr, char *buf)
536 {
537 int nid = dev->id;
538 int len = 0;
539 int i;
540
541 /*
542 * buf is currently PAGE_SIZE in length and each node needs 4 chars
543 * at the most (distance + space or newline).
544 */
545 BUILD_BUG_ON(MAX_NUMNODES * 4 > PAGE_SIZE);
546
547 for_each_online_node(i) {
548 len += sysfs_emit_at(buf, len, "%s%d",
549 i ? " " : "", node_distance(nid, i));
550 }
551
552 len += sysfs_emit_at(buf, len, "\n");
553 return len;
554 }
555 static DEVICE_ATTR(distance, 0444, node_read_distance, NULL);
556
557 static struct attribute *node_dev_attrs[] = {
558 &dev_attr_cpumap.attr,
559 &dev_attr_cpulist.attr,
560 &dev_attr_meminfo.attr,
561 &dev_attr_numastat.attr,
562 &dev_attr_distance.attr,
563 &dev_attr_vmstat.attr,
564 NULL
565 };
566 ATTRIBUTE_GROUPS(node_dev);
567
568 #ifdef CONFIG_HUGETLBFS
569 /*
570 * hugetlbfs per node attributes registration interface:
571 * When/if hugetlb[fs] subsystem initializes [sometime after this module],
572 * it will register its per node attributes for all online nodes with
573 * memory. It will also call register_hugetlbfs_with_node(), below, to
574 * register its attribute registration functions with this node driver.
575 * Once these hooks have been initialized, the node driver will call into
576 * the hugetlb module to [un]register attributes for hot-plugged nodes.
577 */
578 static node_registration_func_t __hugetlb_register_node;
579 static node_registration_func_t __hugetlb_unregister_node;
580
hugetlb_register_node(struct node * node)581 static inline bool hugetlb_register_node(struct node *node)
582 {
583 if (__hugetlb_register_node &&
584 node_state(node->dev.id, N_MEMORY)) {
585 __hugetlb_register_node(node);
586 return true;
587 }
588 return false;
589 }
590
hugetlb_unregister_node(struct node * node)591 static inline void hugetlb_unregister_node(struct node *node)
592 {
593 if (__hugetlb_unregister_node)
594 __hugetlb_unregister_node(node);
595 }
596
register_hugetlbfs_with_node(node_registration_func_t doregister,node_registration_func_t unregister)597 void register_hugetlbfs_with_node(node_registration_func_t doregister,
598 node_registration_func_t unregister)
599 {
600 __hugetlb_register_node = doregister;
601 __hugetlb_unregister_node = unregister;
602 }
603 #else
hugetlb_register_node(struct node * node)604 static inline void hugetlb_register_node(struct node *node) {}
605
hugetlb_unregister_node(struct node * node)606 static inline void hugetlb_unregister_node(struct node *node) {}
607 #endif
608
node_device_release(struct device * dev)609 static void node_device_release(struct device *dev)
610 {
611 struct node *node = to_node(dev);
612
613 #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HUGETLBFS)
614 /*
615 * We schedule the work only when a memory section is
616 * onlined/offlined on this node. When we come here,
617 * all the memory on this node has been offlined,
618 * so we won't enqueue new work to this work.
619 *
620 * The work is using node->node_work, so we should
621 * flush work before freeing the memory.
622 */
623 flush_work(&node->node_work);
624 #endif
625 kfree(node);
626 }
627
628 /*
629 * register_node - Setup a sysfs device for a node.
630 * @num - Node number to use when creating the device.
631 *
632 * Initialize and register the node device.
633 */
register_node(struct node * node,int num)634 static int register_node(struct node *node, int num)
635 {
636 int error;
637
638 node->dev.id = num;
639 node->dev.bus = &node_subsys;
640 node->dev.release = node_device_release;
641 node->dev.groups = node_dev_groups;
642 error = device_register(&node->dev);
643
644 if (error)
645 put_device(&node->dev);
646 else {
647 hugetlb_register_node(node);
648
649 compaction_register_node(node);
650 }
651 return error;
652 }
653
654 /**
655 * unregister_node - unregister a node device
656 * @node: node going away
657 *
658 * Unregisters a node device @node. All the devices on the node must be
659 * unregistered before calling this function.
660 */
unregister_node(struct node * node)661 void unregister_node(struct node *node)
662 {
663 hugetlb_unregister_node(node); /* no-op, if memoryless node */
664 node_remove_accesses(node);
665 node_remove_caches(node);
666 device_unregister(&node->dev);
667 }
668
669 struct node *node_devices[MAX_NUMNODES];
670
671 /*
672 * register cpu under node
673 */
register_cpu_under_node(unsigned int cpu,unsigned int nid)674 int register_cpu_under_node(unsigned int cpu, unsigned int nid)
675 {
676 int ret;
677 struct device *obj;
678
679 if (!node_online(nid))
680 return 0;
681
682 obj = get_cpu_device(cpu);
683 if (!obj)
684 return 0;
685
686 ret = sysfs_create_link(&node_devices[nid]->dev.kobj,
687 &obj->kobj,
688 kobject_name(&obj->kobj));
689 if (ret)
690 return ret;
691
692 return sysfs_create_link(&obj->kobj,
693 &node_devices[nid]->dev.kobj,
694 kobject_name(&node_devices[nid]->dev.kobj));
695 }
696
697 /**
698 * register_memory_node_under_compute_node - link memory node to its compute
699 * node for a given access class.
700 * @mem_nid: Memory node number
701 * @cpu_nid: Cpu node number
702 * @access: Access class to register
703 *
704 * Description:
705 * For use with platforms that may have separate memory and compute nodes.
706 * This function will export node relationships linking which memory
707 * initiator nodes can access memory targets at a given ranked access
708 * class.
709 */
register_memory_node_under_compute_node(unsigned int mem_nid,unsigned int cpu_nid,unsigned access)710 int register_memory_node_under_compute_node(unsigned int mem_nid,
711 unsigned int cpu_nid,
712 unsigned access)
713 {
714 struct node *init_node, *targ_node;
715 struct node_access_nodes *initiator, *target;
716 int ret;
717
718 if (!node_online(cpu_nid) || !node_online(mem_nid))
719 return -ENODEV;
720
721 init_node = node_devices[cpu_nid];
722 targ_node = node_devices[mem_nid];
723 initiator = node_init_node_access(init_node, access);
724 target = node_init_node_access(targ_node, access);
725 if (!initiator || !target)
726 return -ENOMEM;
727
728 ret = sysfs_add_link_to_group(&initiator->dev.kobj, "targets",
729 &targ_node->dev.kobj,
730 dev_name(&targ_node->dev));
731 if (ret)
732 return ret;
733
734 ret = sysfs_add_link_to_group(&target->dev.kobj, "initiators",
735 &init_node->dev.kobj,
736 dev_name(&init_node->dev));
737 if (ret)
738 goto err;
739
740 return 0;
741 err:
742 sysfs_remove_link_from_group(&initiator->dev.kobj, "targets",
743 dev_name(&targ_node->dev));
744 return ret;
745 }
746
unregister_cpu_under_node(unsigned int cpu,unsigned int nid)747 int unregister_cpu_under_node(unsigned int cpu, unsigned int nid)
748 {
749 struct device *obj;
750
751 if (!node_online(nid))
752 return 0;
753
754 obj = get_cpu_device(cpu);
755 if (!obj)
756 return 0;
757
758 sysfs_remove_link(&node_devices[nid]->dev.kobj,
759 kobject_name(&obj->kobj));
760 sysfs_remove_link(&obj->kobj,
761 kobject_name(&node_devices[nid]->dev.kobj));
762
763 return 0;
764 }
765
766 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
get_nid_for_pfn(unsigned long pfn)767 static int __ref get_nid_for_pfn(unsigned long pfn)
768 {
769 if (!pfn_valid_within(pfn))
770 return -1;
771 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
772 if (system_state < SYSTEM_RUNNING)
773 return early_pfn_to_nid(pfn);
774 #endif
775 return pfn_to_nid(pfn);
776 }
777
do_register_memory_block_under_node(int nid,struct memory_block * mem_blk)778 static void do_register_memory_block_under_node(int nid,
779 struct memory_block *mem_blk)
780 {
781 int ret;
782
783 /*
784 * If this memory block spans multiple nodes, we only indicate
785 * the last processed node.
786 */
787 mem_blk->nid = nid;
788
789 ret = sysfs_create_link_nowarn(&node_devices[nid]->dev.kobj,
790 &mem_blk->dev.kobj,
791 kobject_name(&mem_blk->dev.kobj));
792 if (ret && ret != -EEXIST)
793 dev_err_ratelimited(&node_devices[nid]->dev,
794 "can't create link to %s in sysfs (%d)\n",
795 kobject_name(&mem_blk->dev.kobj), ret);
796
797 ret = sysfs_create_link_nowarn(&mem_blk->dev.kobj,
798 &node_devices[nid]->dev.kobj,
799 kobject_name(&node_devices[nid]->dev.kobj));
800 if (ret && ret != -EEXIST)
801 dev_err_ratelimited(&mem_blk->dev,
802 "can't create link to %s in sysfs (%d)\n",
803 kobject_name(&node_devices[nid]->dev.kobj),
804 ret);
805 }
806
807 /* register memory section under specified node if it spans that node */
register_mem_block_under_node_early(struct memory_block * mem_blk,void * arg)808 static int register_mem_block_under_node_early(struct memory_block *mem_blk,
809 void *arg)
810 {
811 unsigned long memory_block_pfns = memory_block_size_bytes() / PAGE_SIZE;
812 unsigned long start_pfn = section_nr_to_pfn(mem_blk->start_section_nr);
813 unsigned long end_pfn = start_pfn + memory_block_pfns - 1;
814 int nid = *(int *)arg;
815 unsigned long pfn;
816
817 for (pfn = start_pfn; pfn <= end_pfn; pfn++) {
818 int page_nid;
819
820 /*
821 * memory block could have several absent sections from start.
822 * skip pfn range from absent section
823 */
824 if (!pfn_in_present_section(pfn)) {
825 pfn = round_down(pfn + PAGES_PER_SECTION,
826 PAGES_PER_SECTION) - 1;
827 continue;
828 }
829
830 /*
831 * We need to check if page belongs to nid only at the boot
832 * case because node's ranges can be interleaved.
833 */
834 page_nid = get_nid_for_pfn(pfn);
835 if (page_nid < 0)
836 continue;
837 if (page_nid != nid)
838 continue;
839
840 do_register_memory_block_under_node(nid, mem_blk);
841 return 0;
842 }
843 /* mem section does not span the specified node */
844 return 0;
845 }
846
847 /*
848 * During hotplug we know that all pages in the memory block belong to the same
849 * node.
850 */
register_mem_block_under_node_hotplug(struct memory_block * mem_blk,void * arg)851 static int register_mem_block_under_node_hotplug(struct memory_block *mem_blk,
852 void *arg)
853 {
854 int nid = *(int *)arg;
855
856 do_register_memory_block_under_node(nid, mem_blk);
857 return 0;
858 }
859
860 /*
861 * Unregister a memory block device under the node it spans. Memory blocks
862 * with multiple nodes cannot be offlined and therefore also never be removed.
863 */
unregister_memory_block_under_nodes(struct memory_block * mem_blk)864 void unregister_memory_block_under_nodes(struct memory_block *mem_blk)
865 {
866 if (mem_blk->nid == NUMA_NO_NODE)
867 return;
868
869 sysfs_remove_link(&node_devices[mem_blk->nid]->dev.kobj,
870 kobject_name(&mem_blk->dev.kobj));
871 sysfs_remove_link(&mem_blk->dev.kobj,
872 kobject_name(&node_devices[mem_blk->nid]->dev.kobj));
873 }
874
link_mem_sections(int nid,unsigned long start_pfn,unsigned long end_pfn,enum meminit_context context)875 void link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn,
876 enum meminit_context context)
877 {
878 walk_memory_blocks_func_t func;
879
880 if (context == MEMINIT_HOTPLUG)
881 func = register_mem_block_under_node_hotplug;
882 else
883 func = register_mem_block_under_node_early;
884
885 walk_memory_blocks(PFN_PHYS(start_pfn), PFN_PHYS(end_pfn - start_pfn),
886 (void *)&nid, func);
887 return;
888 }
889
890 #ifdef CONFIG_HUGETLBFS
891 /*
892 * Handle per node hstate attribute [un]registration on transistions
893 * to/from memoryless state.
894 */
node_hugetlb_work(struct work_struct * work)895 static void node_hugetlb_work(struct work_struct *work)
896 {
897 struct node *node = container_of(work, struct node, node_work);
898
899 /*
900 * We only get here when a node transitions to/from memoryless state.
901 * We can detect which transition occurred by examining whether the
902 * node has memory now. hugetlb_register_node() already check this
903 * so we try to register the attributes. If that fails, then the
904 * node has transitioned to memoryless, try to unregister the
905 * attributes.
906 */
907 if (!hugetlb_register_node(node))
908 hugetlb_unregister_node(node);
909 }
910
init_node_hugetlb_work(int nid)911 static void init_node_hugetlb_work(int nid)
912 {
913 INIT_WORK(&node_devices[nid]->node_work, node_hugetlb_work);
914 }
915
node_memory_callback(struct notifier_block * self,unsigned long action,void * arg)916 static int node_memory_callback(struct notifier_block *self,
917 unsigned long action, void *arg)
918 {
919 struct memory_notify *mnb = arg;
920 int nid = mnb->status_change_nid;
921
922 switch (action) {
923 case MEM_ONLINE:
924 case MEM_OFFLINE:
925 /*
926 * offload per node hstate [un]registration to a work thread
927 * when transitioning to/from memoryless state.
928 */
929 if (nid != NUMA_NO_NODE)
930 schedule_work(&node_devices[nid]->node_work);
931 break;
932
933 case MEM_GOING_ONLINE:
934 case MEM_GOING_OFFLINE:
935 case MEM_CANCEL_ONLINE:
936 case MEM_CANCEL_OFFLINE:
937 default:
938 break;
939 }
940
941 return NOTIFY_OK;
942 }
943 #endif /* CONFIG_HUGETLBFS */
944 #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
945
946 #if !defined(CONFIG_MEMORY_HOTPLUG_SPARSE) || \
947 !defined(CONFIG_HUGETLBFS)
node_memory_callback(struct notifier_block * self,unsigned long action,void * arg)948 static inline int node_memory_callback(struct notifier_block *self,
949 unsigned long action, void *arg)
950 {
951 return NOTIFY_OK;
952 }
953
init_node_hugetlb_work(int nid)954 static void init_node_hugetlb_work(int nid) { }
955
956 #endif
957
__register_one_node(int nid)958 int __register_one_node(int nid)
959 {
960 int error;
961 int cpu;
962
963 node_devices[nid] = kzalloc(sizeof(struct node), GFP_KERNEL);
964 if (!node_devices[nid])
965 return -ENOMEM;
966
967 error = register_node(node_devices[nid], nid);
968
969 /* link cpu under this node */
970 for_each_present_cpu(cpu) {
971 if (cpu_to_node(cpu) == nid)
972 register_cpu_under_node(cpu, nid);
973 }
974
975 INIT_LIST_HEAD(&node_devices[nid]->access_list);
976 /* initialize work queue for memory hot plug */
977 init_node_hugetlb_work(nid);
978 node_init_caches(nid);
979
980 return error;
981 }
982
unregister_one_node(int nid)983 void unregister_one_node(int nid)
984 {
985 if (!node_devices[nid])
986 return;
987
988 unregister_node(node_devices[nid]);
989 node_devices[nid] = NULL;
990 }
991
992 /*
993 * node states attributes
994 */
995
996 struct node_attr {
997 struct device_attribute attr;
998 enum node_states state;
999 };
1000
show_node_state(struct device * dev,struct device_attribute * attr,char * buf)1001 static ssize_t show_node_state(struct device *dev,
1002 struct device_attribute *attr, char *buf)
1003 {
1004 struct node_attr *na = container_of(attr, struct node_attr, attr);
1005
1006 return sysfs_emit(buf, "%*pbl\n",
1007 nodemask_pr_args(&node_states[na->state]));
1008 }
1009
1010 #define _NODE_ATTR(name, state) \
1011 { __ATTR(name, 0444, show_node_state, NULL), state }
1012
1013 static struct node_attr node_state_attr[] = {
1014 [N_POSSIBLE] = _NODE_ATTR(possible, N_POSSIBLE),
1015 [N_ONLINE] = _NODE_ATTR(online, N_ONLINE),
1016 [N_NORMAL_MEMORY] = _NODE_ATTR(has_normal_memory, N_NORMAL_MEMORY),
1017 #ifdef CONFIG_HIGHMEM
1018 [N_HIGH_MEMORY] = _NODE_ATTR(has_high_memory, N_HIGH_MEMORY),
1019 #endif
1020 [N_MEMORY] = _NODE_ATTR(has_memory, N_MEMORY),
1021 [N_CPU] = _NODE_ATTR(has_cpu, N_CPU),
1022 [N_GENERIC_INITIATOR] = _NODE_ATTR(has_generic_initiator,
1023 N_GENERIC_INITIATOR),
1024 };
1025
1026 static struct attribute *node_state_attrs[] = {
1027 &node_state_attr[N_POSSIBLE].attr.attr,
1028 &node_state_attr[N_ONLINE].attr.attr,
1029 &node_state_attr[N_NORMAL_MEMORY].attr.attr,
1030 #ifdef CONFIG_HIGHMEM
1031 &node_state_attr[N_HIGH_MEMORY].attr.attr,
1032 #endif
1033 &node_state_attr[N_MEMORY].attr.attr,
1034 &node_state_attr[N_CPU].attr.attr,
1035 &node_state_attr[N_GENERIC_INITIATOR].attr.attr,
1036 NULL
1037 };
1038
1039 static struct attribute_group memory_root_attr_group = {
1040 .attrs = node_state_attrs,
1041 };
1042
1043 static const struct attribute_group *cpu_root_attr_groups[] = {
1044 &memory_root_attr_group,
1045 NULL,
1046 };
1047
1048 #define NODE_CALLBACK_PRI 2 /* lower than SLAB */
register_node_type(void)1049 static int __init register_node_type(void)
1050 {
1051 int ret;
1052
1053 BUILD_BUG_ON(ARRAY_SIZE(node_state_attr) != NR_NODE_STATES);
1054 BUILD_BUG_ON(ARRAY_SIZE(node_state_attrs)-1 != NR_NODE_STATES);
1055
1056 ret = subsys_system_register(&node_subsys, cpu_root_attr_groups);
1057 if (!ret) {
1058 static struct notifier_block node_memory_callback_nb = {
1059 .notifier_call = node_memory_callback,
1060 .priority = NODE_CALLBACK_PRI,
1061 };
1062 register_hotmemory_notifier(&node_memory_callback_nb);
1063 }
1064
1065 /*
1066 * Note: we're not going to unregister the node class if we fail
1067 * to register the node state class attribute files.
1068 */
1069 return ret;
1070 }
1071 postcore_initcall(register_node_type);
1072