projects/linux·blob v5.2-rc6 · refs

1033 lines · 26.8 KiB

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