db769d3148b7487599a7662a8307d0f7017ada32
[muen/linux.git] / drivers / base / node.c
1 /*
2  * Basic Node interface support
3  */
4
5 #include <linux/module.h>
6 #include <linux/init.h>
7 #include <linux/mm.h>
8 #include <linux/memory.h>
9 #include <linux/vmstat.h>
10 #include <linux/notifier.h>
11 #include <linux/node.h>
12 #include <linux/hugetlb.h>
13 #include <linux/compaction.h>
14 #include <linux/cpumask.h>
15 #include <linux/topology.h>
16 #include <linux/nodemask.h>
17 #include <linux/cpu.h>
18 #include <linux/device.h>
19 #include <linux/swap.h>
20 #include <linux/slab.h>
21
22 static struct bus_type node_subsys = {
23         .name = "node",
24         .dev_name = "node",
25 };
26
27
28 static ssize_t node_read_cpumap(struct device *dev, bool list, char *buf)
29 {
30         struct node *node_dev = to_node(dev);
31         const struct cpumask *mask = cpumask_of_node(node_dev->dev.id);
32
33         /* 2008/04/07: buf currently PAGE_SIZE, need 9 chars per 32 bits. */
34         BUILD_BUG_ON((NR_CPUS/32 * 9) > (PAGE_SIZE-1));
35
36         return cpumap_print_to_pagebuf(list, buf, mask);
37 }
38
39 static inline ssize_t node_read_cpumask(struct device *dev,
40                                 struct device_attribute *attr, char *buf)
41 {
42         return node_read_cpumap(dev, false, buf);
43 }
44 static inline ssize_t node_read_cpulist(struct device *dev,
45                                 struct device_attribute *attr, char *buf)
46 {
47         return node_read_cpumap(dev, true, buf);
48 }
49
50 static DEVICE_ATTR(cpumap,  S_IRUGO, node_read_cpumask, NULL);
51 static DEVICE_ATTR(cpulist, S_IRUGO, node_read_cpulist, NULL);
52
53 #define K(x) ((x) << (PAGE_SHIFT - 10))
54 static ssize_t node_read_meminfo(struct device *dev,
55                         struct device_attribute *attr, char *buf)
56 {
57         int n;
58         int nid = dev->id;
59         struct pglist_data *pgdat = NODE_DATA(nid);
60         struct sysinfo i;
61
62         si_meminfo_node(&i, nid);
63         n = sprintf(buf,
64                        "Node %d MemTotal:       %8lu kB\n"
65                        "Node %d MemFree:        %8lu kB\n"
66                        "Node %d MemUsed:        %8lu kB\n"
67                        "Node %d Active:         %8lu kB\n"
68                        "Node %d Inactive:       %8lu kB\n"
69                        "Node %d Active(anon):   %8lu kB\n"
70                        "Node %d Inactive(anon): %8lu kB\n"
71                        "Node %d Active(file):   %8lu kB\n"
72                        "Node %d Inactive(file): %8lu kB\n"
73                        "Node %d Unevictable:    %8lu kB\n"
74                        "Node %d Mlocked:        %8lu kB\n",
75                        nid, K(i.totalram),
76                        nid, K(i.freeram),
77                        nid, K(i.totalram - i.freeram),
78                        nid, K(node_page_state(pgdat, NR_ACTIVE_ANON) +
79                                 node_page_state(pgdat, NR_ACTIVE_FILE)),
80                        nid, K(node_page_state(pgdat, NR_INACTIVE_ANON) +
81                                 node_page_state(pgdat, NR_INACTIVE_FILE)),
82                        nid, K(node_page_state(pgdat, NR_ACTIVE_ANON)),
83                        nid, K(node_page_state(pgdat, NR_INACTIVE_ANON)),
84                        nid, K(node_page_state(pgdat, NR_ACTIVE_FILE)),
85                        nid, K(node_page_state(pgdat, NR_INACTIVE_FILE)),
86                        nid, K(node_page_state(pgdat, NR_UNEVICTABLE)),
87                        nid, K(sum_zone_node_page_state(nid, NR_MLOCK)));
88
89 #ifdef CONFIG_HIGHMEM
90         n += sprintf(buf + n,
91                        "Node %d HighTotal:      %8lu kB\n"
92                        "Node %d HighFree:       %8lu kB\n"
93                        "Node %d LowTotal:       %8lu kB\n"
94                        "Node %d LowFree:        %8lu kB\n",
95                        nid, K(i.totalhigh),
96                        nid, K(i.freehigh),
97                        nid, K(i.totalram - i.totalhigh),
98                        nid, K(i.freeram - i.freehigh));
99 #endif
100         n += sprintf(buf + n,
101                        "Node %d Dirty:          %8lu kB\n"
102                        "Node %d Writeback:      %8lu kB\n"
103                        "Node %d FilePages:      %8lu kB\n"
104                        "Node %d Mapped:         %8lu kB\n"
105                        "Node %d AnonPages:      %8lu kB\n"
106                        "Node %d Shmem:          %8lu kB\n"
107                        "Node %d KernelStack:    %8lu kB\n"
108                        "Node %d PageTables:     %8lu kB\n"
109                        "Node %d NFS_Unstable:   %8lu kB\n"
110                        "Node %d Bounce:         %8lu kB\n"
111                        "Node %d WritebackTmp:   %8lu kB\n"
112                        "Node %d Slab:           %8lu kB\n"
113                        "Node %d SReclaimable:   %8lu kB\n"
114                        "Node %d SUnreclaim:     %8lu kB\n"
115 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
116                        "Node %d AnonHugePages:  %8lu kB\n"
117                        "Node %d ShmemHugePages: %8lu kB\n"
118                        "Node %d ShmemPmdMapped: %8lu kB\n"
119 #endif
120                         ,
121                        nid, K(node_page_state(pgdat, NR_FILE_DIRTY)),
122                        nid, K(node_page_state(pgdat, NR_WRITEBACK)),
123                        nid, K(node_page_state(pgdat, NR_FILE_PAGES)),
124                        nid, K(node_page_state(pgdat, NR_FILE_MAPPED)),
125                        nid, K(node_page_state(pgdat, NR_ANON_MAPPED)),
126                        nid, K(i.sharedram),
127                        nid, sum_zone_node_page_state(nid, NR_KERNEL_STACK_KB),
128                        nid, K(sum_zone_node_page_state(nid, NR_PAGETABLE)),
129                        nid, K(node_page_state(pgdat, NR_UNSTABLE_NFS)),
130                        nid, K(sum_zone_node_page_state(nid, NR_BOUNCE)),
131                        nid, K(node_page_state(pgdat, NR_WRITEBACK_TEMP)),
132                        nid, K(sum_zone_node_page_state(nid, NR_SLAB_RECLAIMABLE) +
133                                 sum_zone_node_page_state(nid, NR_SLAB_UNRECLAIMABLE)),
134                        nid, K(sum_zone_node_page_state(nid, NR_SLAB_RECLAIMABLE)),
135 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
136                        nid, K(sum_zone_node_page_state(nid, NR_SLAB_UNRECLAIMABLE)),
137                        nid, K(node_page_state(pgdat, NR_ANON_THPS) *
138                                        HPAGE_PMD_NR),
139                        nid, K(node_page_state(pgdat, NR_SHMEM_THPS) *
140                                        HPAGE_PMD_NR),
141                        nid, K(node_page_state(pgdat, NR_SHMEM_PMDMAPPED) *
142                                        HPAGE_PMD_NR));
143 #else
144                        nid, K(sum_zone_node_page_state(nid, NR_SLAB_UNRECLAIMABLE)));
145 #endif
146         n += hugetlb_report_node_meminfo(nid, buf + n);
147         return n;
148 }
149
150 #undef K
151 static DEVICE_ATTR(meminfo, S_IRUGO, node_read_meminfo, NULL);
152
153 static ssize_t node_read_numastat(struct device *dev,
154                                 struct device_attribute *attr, char *buf)
155 {
156         return sprintf(buf,
157                        "numa_hit %lu\n"
158                        "numa_miss %lu\n"
159                        "numa_foreign %lu\n"
160                        "interleave_hit %lu\n"
161                        "local_node %lu\n"
162                        "other_node %lu\n",
163                        sum_zone_node_page_state(dev->id, NUMA_HIT),
164                        sum_zone_node_page_state(dev->id, NUMA_MISS),
165                        sum_zone_node_page_state(dev->id, NUMA_FOREIGN),
166                        sum_zone_node_page_state(dev->id, NUMA_INTERLEAVE_HIT),
167                        sum_zone_node_page_state(dev->id, NUMA_LOCAL),
168                        sum_zone_node_page_state(dev->id, NUMA_OTHER));
169 }
170 static DEVICE_ATTR(numastat, S_IRUGO, node_read_numastat, NULL);
171
172 static ssize_t node_read_vmstat(struct device *dev,
173                                 struct device_attribute *attr, char *buf)
174 {
175         int nid = dev->id;
176         struct pglist_data *pgdat = NODE_DATA(nid);
177         int i;
178         int n = 0;
179
180         for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
181                 n += sprintf(buf+n, "%s %lu\n", vmstat_text[i],
182                              sum_zone_node_page_state(nid, i));
183
184         for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++)
185                 n += sprintf(buf+n, "%s %lu\n",
186                              vmstat_text[i + NR_VM_ZONE_STAT_ITEMS],
187                              node_page_state(pgdat, i));
188
189         return n;
190 }
191 static DEVICE_ATTR(vmstat, S_IRUGO, node_read_vmstat, NULL);
192
193 static ssize_t node_read_distance(struct device *dev,
194                         struct device_attribute *attr, char *buf)
195 {
196         int nid = dev->id;
197         int len = 0;
198         int i;
199
200         /*
201          * buf is currently PAGE_SIZE in length and each node needs 4 chars
202          * at the most (distance + space or newline).
203          */
204         BUILD_BUG_ON(MAX_NUMNODES * 4 > PAGE_SIZE);
205
206         for_each_online_node(i)
207                 len += sprintf(buf + len, "%s%d", i ? " " : "", node_distance(nid, i));
208
209         len += sprintf(buf + len, "\n");
210         return len;
211 }
212 static DEVICE_ATTR(distance, S_IRUGO, node_read_distance, NULL);
213
214 static struct attribute *node_dev_attrs[] = {
215         &dev_attr_cpumap.attr,
216         &dev_attr_cpulist.attr,
217         &dev_attr_meminfo.attr,
218         &dev_attr_numastat.attr,
219         &dev_attr_distance.attr,
220         &dev_attr_vmstat.attr,
221         NULL
222 };
223 ATTRIBUTE_GROUPS(node_dev);
224
225 #ifdef CONFIG_HUGETLBFS
226 /*
227  * hugetlbfs per node attributes registration interface:
228  * When/if hugetlb[fs] subsystem initializes [sometime after this module],
229  * it will register its per node attributes for all online nodes with
230  * memory.  It will also call register_hugetlbfs_with_node(), below, to
231  * register its attribute registration functions with this node driver.
232  * Once these hooks have been initialized, the node driver will call into
233  * the hugetlb module to [un]register attributes for hot-plugged nodes.
234  */
235 static node_registration_func_t __hugetlb_register_node;
236 static node_registration_func_t __hugetlb_unregister_node;
237
238 static inline bool hugetlb_register_node(struct node *node)
239 {
240         if (__hugetlb_register_node &&
241                         node_state(node->dev.id, N_MEMORY)) {
242                 __hugetlb_register_node(node);
243                 return true;
244         }
245         return false;
246 }
247
248 static inline void hugetlb_unregister_node(struct node *node)
249 {
250         if (__hugetlb_unregister_node)
251                 __hugetlb_unregister_node(node);
252 }
253
254 void register_hugetlbfs_with_node(node_registration_func_t doregister,
255                                   node_registration_func_t unregister)
256 {
257         __hugetlb_register_node   = doregister;
258         __hugetlb_unregister_node = unregister;
259 }
260 #else
261 static inline void hugetlb_register_node(struct node *node) {}
262
263 static inline void hugetlb_unregister_node(struct node *node) {}
264 #endif
265
266 static void node_device_release(struct device *dev)
267 {
268         struct node *node = to_node(dev);
269
270 #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HUGETLBFS)
271         /*
272          * We schedule the work only when a memory section is
273          * onlined/offlined on this node. When we come here,
274          * all the memory on this node has been offlined,
275          * so we won't enqueue new work to this work.
276          *
277          * The work is using node->node_work, so we should
278          * flush work before freeing the memory.
279          */
280         flush_work(&node->node_work);
281 #endif
282         kfree(node);
283 }
284
285 /*
286  * register_node - Setup a sysfs device for a node.
287  * @num - Node number to use when creating the device.
288  *
289  * Initialize and register the node device.
290  */
291 static int register_node(struct node *node, int num, struct node *parent)
292 {
293         int error;
294
295         node->dev.id = num;
296         node->dev.bus = &node_subsys;
297         node->dev.release = node_device_release;
298         node->dev.groups = node_dev_groups;
299         error = device_register(&node->dev);
300
301         if (!error){
302                 hugetlb_register_node(node);
303
304                 compaction_register_node(node);
305         }
306         return error;
307 }
308
309 /**
310  * unregister_node - unregister a node device
311  * @node: node going away
312  *
313  * Unregisters a node device @node.  All the devices on the node must be
314  * unregistered before calling this function.
315  */
316 void unregister_node(struct node *node)
317 {
318         hugetlb_unregister_node(node);          /* no-op, if memoryless node */
319
320         device_unregister(&node->dev);
321 }
322
323 struct node *node_devices[MAX_NUMNODES];
324
325 /*
326  * register cpu under node
327  */
328 int register_cpu_under_node(unsigned int cpu, unsigned int nid)
329 {
330         int ret;
331         struct device *obj;
332
333         if (!node_online(nid))
334                 return 0;
335
336         obj = get_cpu_device(cpu);
337         if (!obj)
338                 return 0;
339
340         ret = sysfs_create_link(&node_devices[nid]->dev.kobj,
341                                 &obj->kobj,
342                                 kobject_name(&obj->kobj));
343         if (ret)
344                 return ret;
345
346         return sysfs_create_link(&obj->kobj,
347                                  &node_devices[nid]->dev.kobj,
348                                  kobject_name(&node_devices[nid]->dev.kobj));
349 }
350
351 int unregister_cpu_under_node(unsigned int cpu, unsigned int nid)
352 {
353         struct device *obj;
354
355         if (!node_online(nid))
356                 return 0;
357
358         obj = get_cpu_device(cpu);
359         if (!obj)
360                 return 0;
361
362         sysfs_remove_link(&node_devices[nid]->dev.kobj,
363                           kobject_name(&obj->kobj));
364         sysfs_remove_link(&obj->kobj,
365                           kobject_name(&node_devices[nid]->dev.kobj));
366
367         return 0;
368 }
369
370 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
371 static int __ref get_nid_for_pfn(unsigned long pfn)
372 {
373         if (!pfn_valid_within(pfn))
374                 return -1;
375 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
376         if (system_state < SYSTEM_RUNNING)
377                 return early_pfn_to_nid(pfn);
378 #endif
379         return pfn_to_nid(pfn);
380 }
381
382 /* register memory section under specified node if it spans that node */
383 int register_mem_sect_under_node(struct memory_block *mem_blk, int nid)
384 {
385         int ret;
386         unsigned long pfn, sect_start_pfn, sect_end_pfn;
387
388         if (!mem_blk)
389                 return -EFAULT;
390         if (!node_online(nid))
391                 return 0;
392
393         sect_start_pfn = section_nr_to_pfn(mem_blk->start_section_nr);
394         sect_end_pfn = section_nr_to_pfn(mem_blk->end_section_nr);
395         sect_end_pfn += PAGES_PER_SECTION - 1;
396         for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) {
397                 int page_nid;
398
399                 /*
400                  * memory block could have several absent sections from start.
401                  * skip pfn range from absent section
402                  */
403                 if (!pfn_present(pfn)) {
404                         pfn = round_down(pfn + PAGES_PER_SECTION,
405                                          PAGES_PER_SECTION) - 1;
406                         continue;
407                 }
408
409                 page_nid = get_nid_for_pfn(pfn);
410                 if (page_nid < 0)
411                         continue;
412                 if (page_nid != nid)
413                         continue;
414                 ret = sysfs_create_link_nowarn(&node_devices[nid]->dev.kobj,
415                                         &mem_blk->dev.kobj,
416                                         kobject_name(&mem_blk->dev.kobj));
417                 if (ret)
418                         return ret;
419
420                 return sysfs_create_link_nowarn(&mem_blk->dev.kobj,
421                                 &node_devices[nid]->dev.kobj,
422                                 kobject_name(&node_devices[nid]->dev.kobj));
423         }
424         /* mem section does not span the specified node */
425         return 0;
426 }
427
428 /* unregister memory section under all nodes that it spans */
429 int unregister_mem_sect_under_nodes(struct memory_block *mem_blk,
430                                     unsigned long phys_index)
431 {
432         NODEMASK_ALLOC(nodemask_t, unlinked_nodes, GFP_KERNEL);
433         unsigned long pfn, sect_start_pfn, sect_end_pfn;
434
435         if (!mem_blk) {
436                 NODEMASK_FREE(unlinked_nodes);
437                 return -EFAULT;
438         }
439         if (!unlinked_nodes)
440                 return -ENOMEM;
441         nodes_clear(*unlinked_nodes);
442
443         sect_start_pfn = section_nr_to_pfn(phys_index);
444         sect_end_pfn = sect_start_pfn + PAGES_PER_SECTION - 1;
445         for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) {
446                 int nid;
447
448                 nid = get_nid_for_pfn(pfn);
449                 if (nid < 0)
450                         continue;
451                 if (!node_online(nid))
452                         continue;
453                 if (node_test_and_set(nid, *unlinked_nodes))
454                         continue;
455                 sysfs_remove_link(&node_devices[nid]->dev.kobj,
456                          kobject_name(&mem_blk->dev.kobj));
457                 sysfs_remove_link(&mem_blk->dev.kobj,
458                          kobject_name(&node_devices[nid]->dev.kobj));
459         }
460         NODEMASK_FREE(unlinked_nodes);
461         return 0;
462 }
463
464 static int link_mem_sections(int nid)
465 {
466         unsigned long start_pfn = NODE_DATA(nid)->node_start_pfn;
467         unsigned long end_pfn = start_pfn + NODE_DATA(nid)->node_spanned_pages;
468         unsigned long pfn;
469         struct memory_block *mem_blk = NULL;
470         int err = 0;
471
472         for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
473                 unsigned long section_nr = pfn_to_section_nr(pfn);
474                 struct mem_section *mem_sect;
475                 int ret;
476
477                 if (!present_section_nr(section_nr))
478                         continue;
479                 mem_sect = __nr_to_section(section_nr);
480
481                 /* same memblock ? */
482                 if (mem_blk)
483                         if ((section_nr >= mem_blk->start_section_nr) &&
484                             (section_nr <= mem_blk->end_section_nr))
485                                 continue;
486
487                 mem_blk = find_memory_block_hinted(mem_sect, mem_blk);
488
489                 ret = register_mem_sect_under_node(mem_blk, nid);
490                 if (!err)
491                         err = ret;
492
493                 /* discard ref obtained in find_memory_block() */
494         }
495
496         if (mem_blk)
497                 kobject_put(&mem_blk->dev.kobj);
498         return err;
499 }
500
501 #ifdef CONFIG_HUGETLBFS
502 /*
503  * Handle per node hstate attribute [un]registration on transistions
504  * to/from memoryless state.
505  */
506 static void node_hugetlb_work(struct work_struct *work)
507 {
508         struct node *node = container_of(work, struct node, node_work);
509
510         /*
511          * We only get here when a node transitions to/from memoryless state.
512          * We can detect which transition occurred by examining whether the
513          * node has memory now.  hugetlb_register_node() already check this
514          * so we try to register the attributes.  If that fails, then the
515          * node has transitioned to memoryless, try to unregister the
516          * attributes.
517          */
518         if (!hugetlb_register_node(node))
519                 hugetlb_unregister_node(node);
520 }
521
522 static void init_node_hugetlb_work(int nid)
523 {
524         INIT_WORK(&node_devices[nid]->node_work, node_hugetlb_work);
525 }
526
527 static int node_memory_callback(struct notifier_block *self,
528                                 unsigned long action, void *arg)
529 {
530         struct memory_notify *mnb = arg;
531         int nid = mnb->status_change_nid;
532
533         switch (action) {
534         case MEM_ONLINE:
535         case MEM_OFFLINE:
536                 /*
537                  * offload per node hstate [un]registration to a work thread
538                  * when transitioning to/from memoryless state.
539                  */
540                 if (nid != NUMA_NO_NODE)
541                         schedule_work(&node_devices[nid]->node_work);
542                 break;
543
544         case MEM_GOING_ONLINE:
545         case MEM_GOING_OFFLINE:
546         case MEM_CANCEL_ONLINE:
547         case MEM_CANCEL_OFFLINE:
548         default:
549                 break;
550         }
551
552         return NOTIFY_OK;
553 }
554 #endif  /* CONFIG_HUGETLBFS */
555 #else   /* !CONFIG_MEMORY_HOTPLUG_SPARSE */
556
557 static int link_mem_sections(int nid) { return 0; }
558 #endif  /* CONFIG_MEMORY_HOTPLUG_SPARSE */
559
560 #if !defined(CONFIG_MEMORY_HOTPLUG_SPARSE) || \
561     !defined(CONFIG_HUGETLBFS)
562 static inline int node_memory_callback(struct notifier_block *self,
563                                 unsigned long action, void *arg)
564 {
565         return NOTIFY_OK;
566 }
567
568 static void init_node_hugetlb_work(int nid) { }
569
570 #endif
571
572 int register_one_node(int nid)
573 {
574         int error = 0;
575         int cpu;
576
577         if (node_online(nid)) {
578                 int p_node = parent_node(nid);
579                 struct node *parent = NULL;
580
581                 if (p_node != nid)
582                         parent = node_devices[p_node];
583
584                 node_devices[nid] = kzalloc(sizeof(struct node), GFP_KERNEL);
585                 if (!node_devices[nid])
586                         return -ENOMEM;
587
588                 error = register_node(node_devices[nid], nid, parent);
589
590                 /* link cpu under this node */
591                 for_each_present_cpu(cpu) {
592                         if (cpu_to_node(cpu) == nid)
593                                 register_cpu_under_node(cpu, nid);
594                 }
595
596                 /* link memory sections under this node */
597                 error = link_mem_sections(nid);
598
599                 /* initialize work queue for memory hot plug */
600                 init_node_hugetlb_work(nid);
601         }
602
603         return error;
604
605 }
606
607 void unregister_one_node(int nid)
608 {
609         if (!node_devices[nid])
610                 return;
611
612         unregister_node(node_devices[nid]);
613         node_devices[nid] = NULL;
614 }
615
616 /*
617  * node states attributes
618  */
619
620 static ssize_t print_nodes_state(enum node_states state, char *buf)
621 {
622         int n;
623
624         n = scnprintf(buf, PAGE_SIZE - 1, "%*pbl",
625                       nodemask_pr_args(&node_states[state]));
626         buf[n++] = '\n';
627         buf[n] = '\0';
628         return n;
629 }
630
631 struct node_attr {
632         struct device_attribute attr;
633         enum node_states state;
634 };
635
636 static ssize_t show_node_state(struct device *dev,
637                                struct device_attribute *attr, char *buf)
638 {
639         struct node_attr *na = container_of(attr, struct node_attr, attr);
640         return print_nodes_state(na->state, buf);
641 }
642
643 #define _NODE_ATTR(name, state) \
644         { __ATTR(name, 0444, show_node_state, NULL), state }
645
646 static struct node_attr node_state_attr[] = {
647         [N_POSSIBLE] = _NODE_ATTR(possible, N_POSSIBLE),
648         [N_ONLINE] = _NODE_ATTR(online, N_ONLINE),
649         [N_NORMAL_MEMORY] = _NODE_ATTR(has_normal_memory, N_NORMAL_MEMORY),
650 #ifdef CONFIG_HIGHMEM
651         [N_HIGH_MEMORY] = _NODE_ATTR(has_high_memory, N_HIGH_MEMORY),
652 #endif
653 #ifdef CONFIG_MOVABLE_NODE
654         [N_MEMORY] = _NODE_ATTR(has_memory, N_MEMORY),
655 #endif
656         [N_CPU] = _NODE_ATTR(has_cpu, N_CPU),
657 };
658
659 static struct attribute *node_state_attrs[] = {
660         &node_state_attr[N_POSSIBLE].attr.attr,
661         &node_state_attr[N_ONLINE].attr.attr,
662         &node_state_attr[N_NORMAL_MEMORY].attr.attr,
663 #ifdef CONFIG_HIGHMEM
664         &node_state_attr[N_HIGH_MEMORY].attr.attr,
665 #endif
666 #ifdef CONFIG_MOVABLE_NODE
667         &node_state_attr[N_MEMORY].attr.attr,
668 #endif
669         &node_state_attr[N_CPU].attr.attr,
670         NULL
671 };
672
673 static struct attribute_group memory_root_attr_group = {
674         .attrs = node_state_attrs,
675 };
676
677 static const struct attribute_group *cpu_root_attr_groups[] = {
678         &memory_root_attr_group,
679         NULL,
680 };
681
682 #define NODE_CALLBACK_PRI       2       /* lower than SLAB */
683 static int __init register_node_type(void)
684 {
685         int ret;
686
687         BUILD_BUG_ON(ARRAY_SIZE(node_state_attr) != NR_NODE_STATES);
688         BUILD_BUG_ON(ARRAY_SIZE(node_state_attrs)-1 != NR_NODE_STATES);
689
690         ret = subsys_system_register(&node_subsys, cpu_root_attr_groups);
691         if (!ret) {
692                 static struct notifier_block node_memory_callback_nb = {
693                         .notifier_call = node_memory_callback,
694                         .priority = NODE_CALLBACK_PRI,
695                 };
696                 register_hotmemory_notifier(&node_memory_callback_nb);
697         }
698
699         /*
700          * Note:  we're not going to unregister the node class if we fail
701          * to register the node state class attribute files.
702          */
703         return ret;
704 }
705 postcore_initcall(register_node_type);