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v3.1
  1/*
  2 * drivers/base/node.c - basic Node class support
  3 */
  4
  5#include <linux/sysdev.h>
  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/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
 22static struct sysdev_class_attribute *node_state_attrs[];
 23
 24static struct sysdev_class node_class = {
 25	.name = "node",
 26	.attrs = node_state_attrs,
 27};
 28
 29
 30static ssize_t node_read_cpumap(struct sys_device *dev, int type, char *buf)
 31{
 32	struct node *node_dev = to_node(dev);
 33	const struct cpumask *mask = cpumask_of_node(node_dev->sysdev.id);
 34	int len;
 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	len = type?
 40		cpulist_scnprintf(buf, PAGE_SIZE-2, mask) :
 41		cpumask_scnprintf(buf, PAGE_SIZE-2, mask);
 42 	buf[len++] = '\n';
 43 	buf[len] = '\0';
 44	return len;
 45}
 46
 47static inline ssize_t node_read_cpumask(struct sys_device *dev,
 48				struct sysdev_attribute *attr, char *buf)
 49{
 50	return node_read_cpumap(dev, 0, buf);
 51}
 52static inline ssize_t node_read_cpulist(struct sys_device *dev,
 53				struct sysdev_attribute *attr, char *buf)
 54{
 55	return node_read_cpumap(dev, 1, buf);
 56}
 57
 58static SYSDEV_ATTR(cpumap,  S_IRUGO, node_read_cpumask, NULL);
 59static SYSDEV_ATTR(cpulist, S_IRUGO, node_read_cpulist, NULL);
 60
 61#define K(x) ((x) << (PAGE_SHIFT - 10))
 62static ssize_t node_read_meminfo(struct sys_device * dev,
 63			struct sysdev_attribute *attr, char * buf)
 64{
 65	int n;
 66	int nid = dev->id;
 
 67	struct sysinfo i;
 68
 69	si_meminfo_node(&i, nid);
 70	n = sprintf(buf,
 71		       "Node %d MemTotal:       %8lu kB\n"
 72		       "Node %d MemFree:        %8lu kB\n"
 73		       "Node %d MemUsed:        %8lu kB\n"
 74		       "Node %d Active:         %8lu kB\n"
 75		       "Node %d Inactive:       %8lu kB\n"
 76		       "Node %d Active(anon):   %8lu kB\n"
 77		       "Node %d Inactive(anon): %8lu kB\n"
 78		       "Node %d Active(file):   %8lu kB\n"
 79		       "Node %d Inactive(file): %8lu kB\n"
 80		       "Node %d Unevictable:    %8lu kB\n"
 81		       "Node %d Mlocked:        %8lu kB\n",
 82		       nid, K(i.totalram),
 83		       nid, K(i.freeram),
 84		       nid, K(i.totalram - i.freeram),
 85		       nid, K(node_page_state(nid, NR_ACTIVE_ANON) +
 86				node_page_state(nid, NR_ACTIVE_FILE)),
 87		       nid, K(node_page_state(nid, NR_INACTIVE_ANON) +
 88				node_page_state(nid, NR_INACTIVE_FILE)),
 89		       nid, K(node_page_state(nid, NR_ACTIVE_ANON)),
 90		       nid, K(node_page_state(nid, NR_INACTIVE_ANON)),
 91		       nid, K(node_page_state(nid, NR_ACTIVE_FILE)),
 92		       nid, K(node_page_state(nid, NR_INACTIVE_FILE)),
 93		       nid, K(node_page_state(nid, NR_UNEVICTABLE)),
 94		       nid, K(node_page_state(nid, NR_MLOCK)));
 95
 96#ifdef CONFIG_HIGHMEM
 97	n += sprintf(buf + n,
 98		       "Node %d HighTotal:      %8lu kB\n"
 99		       "Node %d HighFree:       %8lu kB\n"
100		       "Node %d LowTotal:       %8lu kB\n"
101		       "Node %d LowFree:        %8lu kB\n",
102		       nid, K(i.totalhigh),
103		       nid, K(i.freehigh),
104		       nid, K(i.totalram - i.totalhigh),
105		       nid, K(i.freeram - i.freehigh));
106#endif
107	n += sprintf(buf + n,
108		       "Node %d Dirty:          %8lu kB\n"
109		       "Node %d Writeback:      %8lu kB\n"
110		       "Node %d FilePages:      %8lu kB\n"
111		       "Node %d Mapped:         %8lu kB\n"
112		       "Node %d AnonPages:      %8lu kB\n"
113		       "Node %d Shmem:          %8lu kB\n"
114		       "Node %d KernelStack:    %8lu kB\n"
115		       "Node %d PageTables:     %8lu kB\n"
116		       "Node %d NFS_Unstable:   %8lu kB\n"
117		       "Node %d Bounce:         %8lu kB\n"
118		       "Node %d WritebackTmp:   %8lu kB\n"
119		       "Node %d Slab:           %8lu kB\n"
120		       "Node %d SReclaimable:   %8lu kB\n"
121		       "Node %d SUnreclaim:     %8lu kB\n"
122#ifdef CONFIG_TRANSPARENT_HUGEPAGE
123		       "Node %d AnonHugePages:  %8lu kB\n"
 
 
124#endif
125			,
126		       nid, K(node_page_state(nid, NR_FILE_DIRTY)),
127		       nid, K(node_page_state(nid, NR_WRITEBACK)),
128		       nid, K(node_page_state(nid, NR_FILE_PAGES)),
129		       nid, K(node_page_state(nid, NR_FILE_MAPPED)),
130		       nid, K(node_page_state(nid, NR_ANON_PAGES)
131#ifdef CONFIG_TRANSPARENT_HUGEPAGE
132			+ node_page_state(nid, NR_ANON_TRANSPARENT_HUGEPAGES) *
133			HPAGE_PMD_NR
134#endif
135		       ),
136		       nid, K(node_page_state(nid, NR_SHMEM)),
137		       nid, node_page_state(nid, NR_KERNEL_STACK) *
138				THREAD_SIZE / 1024,
139		       nid, K(node_page_state(nid, NR_PAGETABLE)),
140		       nid, K(node_page_state(nid, NR_UNSTABLE_NFS)),
141		       nid, K(node_page_state(nid, NR_BOUNCE)),
142		       nid, K(node_page_state(nid, NR_WRITEBACK_TEMP)),
143		       nid, K(node_page_state(nid, NR_SLAB_RECLAIMABLE) +
144				node_page_state(nid, NR_SLAB_UNRECLAIMABLE)),
145		       nid, K(node_page_state(nid, NR_SLAB_RECLAIMABLE)),
146		       nid, K(node_page_state(nid, NR_SLAB_UNRECLAIMABLE))
147#ifdef CONFIG_TRANSPARENT_HUGEPAGE
148			, nid,
149			K(node_page_state(nid, NR_ANON_TRANSPARENT_HUGEPAGES) *
150			HPAGE_PMD_NR)
 
 
 
 
 
 
151#endif
152		       );
153	n += hugetlb_report_node_meminfo(nid, buf + n);
154	return n;
155}
156
157#undef K
158static SYSDEV_ATTR(meminfo, S_IRUGO, node_read_meminfo, NULL);
159
160static ssize_t node_read_numastat(struct sys_device * dev,
161				struct sysdev_attribute *attr, char * buf)
162{
163	return sprintf(buf,
164		       "numa_hit %lu\n"
165		       "numa_miss %lu\n"
166		       "numa_foreign %lu\n"
167		       "interleave_hit %lu\n"
168		       "local_node %lu\n"
169		       "other_node %lu\n",
170		       node_page_state(dev->id, NUMA_HIT),
171		       node_page_state(dev->id, NUMA_MISS),
172		       node_page_state(dev->id, NUMA_FOREIGN),
173		       node_page_state(dev->id, NUMA_INTERLEAVE_HIT),
174		       node_page_state(dev->id, NUMA_LOCAL),
175		       node_page_state(dev->id, NUMA_OTHER));
176}
177static SYSDEV_ATTR(numastat, S_IRUGO, node_read_numastat, NULL);
178
179static ssize_t node_read_vmstat(struct sys_device *dev,
180				struct sysdev_attribute *attr, char *buf)
181{
182	int nid = dev->id;
 
183	int i;
184	int n = 0;
185
186	for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
187		n += sprintf(buf+n, "%s %lu\n", vmstat_text[i],
188			     node_page_state(nid, i));
 
 
 
 
 
189
190	return n;
191}
192static SYSDEV_ATTR(vmstat, S_IRUGO, node_read_vmstat, NULL);
193
194static ssize_t node_read_distance(struct sys_device * dev,
195			struct sysdev_attribute *attr, char * buf)
196{
197	int nid = dev->id;
198	int len = 0;
199	int i;
200
201	/*
202	 * buf is currently PAGE_SIZE in length and each node needs 4 chars
203	 * at the most (distance + space or newline).
204	 */
205	BUILD_BUG_ON(MAX_NUMNODES * 4 > PAGE_SIZE);
206
207	for_each_online_node(i)
208		len += sprintf(buf + len, "%s%d", i ? " " : "", node_distance(nid, i));
209
210	len += sprintf(buf + len, "\n");
211	return len;
212}
213static SYSDEV_ATTR(distance, S_IRUGO, node_read_distance, NULL);
 
 
 
 
 
 
 
 
 
 
 
214
215#ifdef CONFIG_HUGETLBFS
216/*
217 * hugetlbfs per node attributes registration interface:
218 * When/if hugetlb[fs] subsystem initializes [sometime after this module],
219 * it will register its per node attributes for all online nodes with
220 * memory.  It will also call register_hugetlbfs_with_node(), below, to
221 * register its attribute registration functions with this node driver.
222 * Once these hooks have been initialized, the node driver will call into
223 * the hugetlb module to [un]register attributes for hot-plugged nodes.
224 */
225static node_registration_func_t __hugetlb_register_node;
226static node_registration_func_t __hugetlb_unregister_node;
227
228static inline bool hugetlb_register_node(struct node *node)
229{
230	if (__hugetlb_register_node &&
231			node_state(node->sysdev.id, N_HIGH_MEMORY)) {
232		__hugetlb_register_node(node);
233		return true;
234	}
235	return false;
236}
237
238static inline void hugetlb_unregister_node(struct node *node)
239{
240	if (__hugetlb_unregister_node)
241		__hugetlb_unregister_node(node);
242}
243
244void register_hugetlbfs_with_node(node_registration_func_t doregister,
245				  node_registration_func_t unregister)
246{
247	__hugetlb_register_node   = doregister;
248	__hugetlb_unregister_node = unregister;
249}
250#else
251static inline void hugetlb_register_node(struct node *node) {}
252
253static inline void hugetlb_unregister_node(struct node *node) {}
254#endif
255
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
256
257/*
258 * register_node - Setup a sysfs device for a node.
259 * @num - Node number to use when creating the device.
260 *
261 * Initialize and register the node device.
262 */
263int register_node(struct node *node, int num, struct node *parent)
264{
265	int error;
266
267	node->sysdev.id = num;
268	node->sysdev.cls = &node_class;
269	error = sysdev_register(&node->sysdev);
 
 
270
271	if (!error){
272		sysdev_create_file(&node->sysdev, &attr_cpumap);
273		sysdev_create_file(&node->sysdev, &attr_cpulist);
274		sysdev_create_file(&node->sysdev, &attr_meminfo);
275		sysdev_create_file(&node->sysdev, &attr_numastat);
276		sysdev_create_file(&node->sysdev, &attr_distance);
277		sysdev_create_file(&node->sysdev, &attr_vmstat);
278
279		scan_unevictable_register_node(node);
280
281		hugetlb_register_node(node);
282
283		compaction_register_node(node);
284	}
285	return error;
286}
287
288/**
289 * unregister_node - unregister a node device
290 * @node: node going away
291 *
292 * Unregisters a node device @node.  All the devices on the node must be
293 * unregistered before calling this function.
294 */
295void unregister_node(struct node *node)
296{
297	sysdev_remove_file(&node->sysdev, &attr_cpumap);
298	sysdev_remove_file(&node->sysdev, &attr_cpulist);
299	sysdev_remove_file(&node->sysdev, &attr_meminfo);
300	sysdev_remove_file(&node->sysdev, &attr_numastat);
301	sysdev_remove_file(&node->sysdev, &attr_distance);
302	sysdev_remove_file(&node->sysdev, &attr_vmstat);
303
304	scan_unevictable_unregister_node(node);
305	hugetlb_unregister_node(node);		/* no-op, if memoryless node */
306
307	sysdev_unregister(&node->sysdev);
308}
309
310struct node node_devices[MAX_NUMNODES];
311
312/*
313 * register cpu under node
314 */
315int register_cpu_under_node(unsigned int cpu, unsigned int nid)
316{
317	int ret;
318	struct sys_device *obj;
319
320	if (!node_online(nid))
321		return 0;
322
323	obj = get_cpu_sysdev(cpu);
324	if (!obj)
325		return 0;
326
327	ret = sysfs_create_link(&node_devices[nid].sysdev.kobj,
328				&obj->kobj,
329				kobject_name(&obj->kobj));
330	if (ret)
331		return ret;
332
333	return sysfs_create_link(&obj->kobj,
334				 &node_devices[nid].sysdev.kobj,
335				 kobject_name(&node_devices[nid].sysdev.kobj));
336}
337
338int unregister_cpu_under_node(unsigned int cpu, unsigned int nid)
339{
340	struct sys_device *obj;
341
342	if (!node_online(nid))
343		return 0;
344
345	obj = get_cpu_sysdev(cpu);
346	if (!obj)
347		return 0;
348
349	sysfs_remove_link(&node_devices[nid].sysdev.kobj,
350			  kobject_name(&obj->kobj));
351	sysfs_remove_link(&obj->kobj,
352			  kobject_name(&node_devices[nid].sysdev.kobj));
353
354	return 0;
355}
356
357#ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
358#define page_initialized(page)  (page->lru.next)
359
360static int get_nid_for_pfn(unsigned long pfn)
361{
362	struct page *page;
363
364	if (!pfn_valid_within(pfn))
365		return -1;
 
 
 
 
366	page = pfn_to_page(pfn);
367	if (!page_initialized(page))
368		return -1;
369	return pfn_to_nid(pfn);
370}
371
372/* register memory section under specified node if it spans that node */
373int register_mem_sect_under_node(struct memory_block *mem_blk, int nid)
374{
375	int ret;
376	unsigned long pfn, sect_start_pfn, sect_end_pfn;
377
378	if (!mem_blk)
379		return -EFAULT;
380	if (!node_online(nid))
381		return 0;
382
383	sect_start_pfn = section_nr_to_pfn(mem_blk->start_section_nr);
384	sect_end_pfn = section_nr_to_pfn(mem_blk->end_section_nr);
385	sect_end_pfn += PAGES_PER_SECTION - 1;
386	for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) {
387		int page_nid;
388
 
 
 
 
 
 
 
 
 
 
389		page_nid = get_nid_for_pfn(pfn);
390		if (page_nid < 0)
391			continue;
392		if (page_nid != nid)
393			continue;
394		ret = sysfs_create_link_nowarn(&node_devices[nid].sysdev.kobj,
395					&mem_blk->sysdev.kobj,
396					kobject_name(&mem_blk->sysdev.kobj));
397		if (ret)
398			return ret;
399
400		return sysfs_create_link_nowarn(&mem_blk->sysdev.kobj,
401				&node_devices[nid].sysdev.kobj,
402				kobject_name(&node_devices[nid].sysdev.kobj));
403	}
404	/* mem section does not span the specified node */
405	return 0;
406}
407
408/* unregister memory section under all nodes that it spans */
409int unregister_mem_sect_under_nodes(struct memory_block *mem_blk,
410				    unsigned long phys_index)
411{
412	NODEMASK_ALLOC(nodemask_t, unlinked_nodes, GFP_KERNEL);
413	unsigned long pfn, sect_start_pfn, sect_end_pfn;
414
415	if (!mem_blk) {
416		NODEMASK_FREE(unlinked_nodes);
417		return -EFAULT;
418	}
419	if (!unlinked_nodes)
420		return -ENOMEM;
421	nodes_clear(*unlinked_nodes);
422
423	sect_start_pfn = section_nr_to_pfn(phys_index);
424	sect_end_pfn = sect_start_pfn + PAGES_PER_SECTION - 1;
425	for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) {
426		int nid;
427
428		nid = get_nid_for_pfn(pfn);
429		if (nid < 0)
430			continue;
431		if (!node_online(nid))
432			continue;
433		if (node_test_and_set(nid, *unlinked_nodes))
434			continue;
435		sysfs_remove_link(&node_devices[nid].sysdev.kobj,
436			 kobject_name(&mem_blk->sysdev.kobj));
437		sysfs_remove_link(&mem_blk->sysdev.kobj,
438			 kobject_name(&node_devices[nid].sysdev.kobj));
439	}
440	NODEMASK_FREE(unlinked_nodes);
441	return 0;
442}
443
444static int link_mem_sections(int nid)
445{
446	unsigned long start_pfn = NODE_DATA(nid)->node_start_pfn;
447	unsigned long end_pfn = start_pfn + NODE_DATA(nid)->node_spanned_pages;
448	unsigned long pfn;
449	struct memory_block *mem_blk = NULL;
450	int err = 0;
451
452	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
453		unsigned long section_nr = pfn_to_section_nr(pfn);
454		struct mem_section *mem_sect;
455		int ret;
456
457		if (!present_section_nr(section_nr))
458			continue;
459		mem_sect = __nr_to_section(section_nr);
 
 
 
 
 
 
 
460		mem_blk = find_memory_block_hinted(mem_sect, mem_blk);
 
461		ret = register_mem_sect_under_node(mem_blk, nid);
462		if (!err)
463			err = ret;
464
465		/* discard ref obtained in find_memory_block() */
466	}
467
468	if (mem_blk)
469		kobject_put(&mem_blk->sysdev.kobj);
470	return err;
471}
472
473#ifdef CONFIG_HUGETLBFS
474/*
475 * Handle per node hstate attribute [un]registration on transistions
476 * to/from memoryless state.
477 */
478static void node_hugetlb_work(struct work_struct *work)
479{
480	struct node *node = container_of(work, struct node, node_work);
481
482	/*
483	 * We only get here when a node transitions to/from memoryless state.
484	 * We can detect which transition occurred by examining whether the
485	 * node has memory now.  hugetlb_register_node() already check this
486	 * so we try to register the attributes.  If that fails, then the
487	 * node has transitioned to memoryless, try to unregister the
488	 * attributes.
489	 */
490	if (!hugetlb_register_node(node))
491		hugetlb_unregister_node(node);
492}
493
494static void init_node_hugetlb_work(int nid)
495{
496	INIT_WORK(&node_devices[nid].node_work, node_hugetlb_work);
497}
498
499static int node_memory_callback(struct notifier_block *self,
500				unsigned long action, void *arg)
501{
502	struct memory_notify *mnb = arg;
503	int nid = mnb->status_change_nid;
504
505	switch (action) {
506	case MEM_ONLINE:
507	case MEM_OFFLINE:
508		/*
509		 * offload per node hstate [un]registration to a work thread
510		 * when transitioning to/from memoryless state.
511		 */
512		if (nid != NUMA_NO_NODE)
513			schedule_work(&node_devices[nid].node_work);
514		break;
515
516	case MEM_GOING_ONLINE:
517	case MEM_GOING_OFFLINE:
518	case MEM_CANCEL_ONLINE:
519	case MEM_CANCEL_OFFLINE:
520	default:
521		break;
522	}
523
524	return NOTIFY_OK;
525}
526#endif	/* CONFIG_HUGETLBFS */
527#else	/* !CONFIG_MEMORY_HOTPLUG_SPARSE */
528
529static int link_mem_sections(int nid) { return 0; }
530#endif	/* CONFIG_MEMORY_HOTPLUG_SPARSE */
531
532#if !defined(CONFIG_MEMORY_HOTPLUG_SPARSE) || \
533    !defined(CONFIG_HUGETLBFS)
534static inline int node_memory_callback(struct notifier_block *self,
535				unsigned long action, void *arg)
536{
537	return NOTIFY_OK;
538}
539
540static void init_node_hugetlb_work(int nid) { }
541
542#endif
543
544int register_one_node(int nid)
545{
546	int error = 0;
547	int cpu;
548
549	if (node_online(nid)) {
550		int p_node = parent_node(nid);
551		struct node *parent = NULL;
552
553		if (p_node != nid)
554			parent = &node_devices[p_node];
 
 
 
 
555
556		error = register_node(&node_devices[nid], nid, parent);
557
558		/* link cpu under this node */
559		for_each_present_cpu(cpu) {
560			if (cpu_to_node(cpu) == nid)
561				register_cpu_under_node(cpu, nid);
562		}
563
564		/* link memory sections under this node */
565		error = link_mem_sections(nid);
566
567		/* initialize work queue for memory hot plug */
568		init_node_hugetlb_work(nid);
569	}
570
571	return error;
572
573}
574
575void unregister_one_node(int nid)
576{
577	unregister_node(&node_devices[nid]);
 
 
 
 
578}
579
580/*
581 * node states attributes
582 */
583
584static ssize_t print_nodes_state(enum node_states state, char *buf)
585{
586	int n;
587
588	n = nodelist_scnprintf(buf, PAGE_SIZE, node_states[state]);
589	if (n > 0 && PAGE_SIZE > n + 1) {
590		*(buf + n++) = '\n';
591		*(buf + n++) = '\0';
592	}
593	return n;
594}
595
596struct node_attr {
597	struct sysdev_class_attribute attr;
598	enum node_states state;
599};
600
601static ssize_t show_node_state(struct sysdev_class *class,
602			       struct sysdev_class_attribute *attr, char *buf)
603{
604	struct node_attr *na = container_of(attr, struct node_attr, attr);
605	return print_nodes_state(na->state, buf);
606}
607
608#define _NODE_ATTR(name, state) \
609	{ _SYSDEV_CLASS_ATTR(name, 0444, show_node_state, NULL), state }
610
611static struct node_attr node_state_attr[] = {
612	_NODE_ATTR(possible, N_POSSIBLE),
613	_NODE_ATTR(online, N_ONLINE),
614	_NODE_ATTR(has_normal_memory, N_NORMAL_MEMORY),
615	_NODE_ATTR(has_cpu, N_CPU),
616#ifdef CONFIG_HIGHMEM
617	_NODE_ATTR(has_high_memory, N_HIGH_MEMORY),
 
 
 
618#endif
 
619};
620
621static struct sysdev_class_attribute *node_state_attrs[] = {
622	&node_state_attr[0].attr,
623	&node_state_attr[1].attr,
624	&node_state_attr[2].attr,
625	&node_state_attr[3].attr,
626#ifdef CONFIG_HIGHMEM
627	&node_state_attr[4].attr,
628#endif
 
 
 
 
629	NULL
630};
631
 
 
 
 
 
 
 
 
 
632#define NODE_CALLBACK_PRI	2	/* lower than SLAB */
633static int __init register_node_type(void)
634{
635	int ret;
636
637 	BUILD_BUG_ON(ARRAY_SIZE(node_state_attr) != NR_NODE_STATES);
638 	BUILD_BUG_ON(ARRAY_SIZE(node_state_attrs)-1 != NR_NODE_STATES);
639
640	ret = sysdev_class_register(&node_class);
641	if (!ret) {
642		hotplug_memory_notifier(node_memory_callback,
643					NODE_CALLBACK_PRI);
 
 
 
644	}
645
646	/*
647	 * Note:  we're not going to unregister the node class if we fail
648	 * to register the node state class attribute files.
649	 */
650	return ret;
651}
652postcore_initcall(register_node_type);
v4.10.11
  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
 22static struct bus_type node_subsys = {
 
 
 23	.name = "node",
 24	.dev_name = "node",
 25};
 26
 27
 28static 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
 39static 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}
 44static 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
 50static DEVICE_ATTR(cpumap,  S_IRUGO, node_read_cpumask, NULL);
 51static DEVICE_ATTR(cpulist, S_IRUGO, node_read_cpulist, NULL);
 52
 53#define K(x) ((x) << (PAGE_SHIFT - 10))
 54static 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
151static DEVICE_ATTR(meminfo, S_IRUGO, node_read_meminfo, NULL);
152
153static 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}
170static DEVICE_ATTR(numastat, S_IRUGO, node_read_numastat, NULL);
171
172static 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}
191static DEVICE_ATTR(vmstat, S_IRUGO, node_read_vmstat, NULL);
192
193static 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}
212static DEVICE_ATTR(distance, S_IRUGO, node_read_distance, NULL);
213
214static 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};
223ATTRIBUTE_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 */
235static node_registration_func_t __hugetlb_register_node;
236static node_registration_func_t __hugetlb_unregister_node;
237
238static 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
248static inline void hugetlb_unregister_node(struct node *node)
249{
250	if (__hugetlb_unregister_node)
251		__hugetlb_unregister_node(node);
252}
253
254void 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
261static inline void hugetlb_register_node(struct node *node) {}
262
263static inline void hugetlb_unregister_node(struct node *node) {}
264#endif
265
266static 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 */
291static 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 */
316void unregister_node(struct node *node)
317{
 
 
 
 
 
 
 
 
318	hugetlb_unregister_node(node);		/* no-op, if memoryless node */
319
320	device_unregister(&node->dev);
321}
322
323struct node *node_devices[MAX_NUMNODES];
324
325/*
326 * register cpu under node
327 */
328int 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
351int 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#define page_initialized(page)  (page->lru.next)
372
373static int __ref get_nid_for_pfn(unsigned long pfn)
374{
375	struct page *page;
376
377	if (!pfn_valid_within(pfn))
378		return -1;
379#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
380	if (system_state == SYSTEM_BOOTING)
381		return early_pfn_to_nid(pfn);
382#endif
383	page = pfn_to_page(pfn);
384	if (!page_initialized(page))
385		return -1;
386	return pfn_to_nid(pfn);
387}
388
389/* register memory section under specified node if it spans that node */
390int register_mem_sect_under_node(struct memory_block *mem_blk, int nid)
391{
392	int ret;
393	unsigned long pfn, sect_start_pfn, sect_end_pfn;
394
395	if (!mem_blk)
396		return -EFAULT;
397	if (!node_online(nid))
398		return 0;
399
400	sect_start_pfn = section_nr_to_pfn(mem_blk->start_section_nr);
401	sect_end_pfn = section_nr_to_pfn(mem_blk->end_section_nr);
402	sect_end_pfn += PAGES_PER_SECTION - 1;
403	for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) {
404		int page_nid;
405
406		/*
407		 * memory block could have several absent sections from start.
408		 * skip pfn range from absent section
409		 */
410		if (!pfn_present(pfn)) {
411			pfn = round_down(pfn + PAGES_PER_SECTION,
412					 PAGES_PER_SECTION) - 1;
413			continue;
414		}
415
416		page_nid = get_nid_for_pfn(pfn);
417		if (page_nid < 0)
418			continue;
419		if (page_nid != nid)
420			continue;
421		ret = sysfs_create_link_nowarn(&node_devices[nid]->dev.kobj,
422					&mem_blk->dev.kobj,
423					kobject_name(&mem_blk->dev.kobj));
424		if (ret)
425			return ret;
426
427		return sysfs_create_link_nowarn(&mem_blk->dev.kobj,
428				&node_devices[nid]->dev.kobj,
429				kobject_name(&node_devices[nid]->dev.kobj));
430	}
431	/* mem section does not span the specified node */
432	return 0;
433}
434
435/* unregister memory section under all nodes that it spans */
436int unregister_mem_sect_under_nodes(struct memory_block *mem_blk,
437				    unsigned long phys_index)
438{
439	NODEMASK_ALLOC(nodemask_t, unlinked_nodes, GFP_KERNEL);
440	unsigned long pfn, sect_start_pfn, sect_end_pfn;
441
442	if (!mem_blk) {
443		NODEMASK_FREE(unlinked_nodes);
444		return -EFAULT;
445	}
446	if (!unlinked_nodes)
447		return -ENOMEM;
448	nodes_clear(*unlinked_nodes);
449
450	sect_start_pfn = section_nr_to_pfn(phys_index);
451	sect_end_pfn = sect_start_pfn + PAGES_PER_SECTION - 1;
452	for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) {
453		int nid;
454
455		nid = get_nid_for_pfn(pfn);
456		if (nid < 0)
457			continue;
458		if (!node_online(nid))
459			continue;
460		if (node_test_and_set(nid, *unlinked_nodes))
461			continue;
462		sysfs_remove_link(&node_devices[nid]->dev.kobj,
463			 kobject_name(&mem_blk->dev.kobj));
464		sysfs_remove_link(&mem_blk->dev.kobj,
465			 kobject_name(&node_devices[nid]->dev.kobj));
466	}
467	NODEMASK_FREE(unlinked_nodes);
468	return 0;
469}
470
471static int link_mem_sections(int nid)
472{
473	unsigned long start_pfn = NODE_DATA(nid)->node_start_pfn;
474	unsigned long end_pfn = start_pfn + NODE_DATA(nid)->node_spanned_pages;
475	unsigned long pfn;
476	struct memory_block *mem_blk = NULL;
477	int err = 0;
478
479	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
480		unsigned long section_nr = pfn_to_section_nr(pfn);
481		struct mem_section *mem_sect;
482		int ret;
483
484		if (!present_section_nr(section_nr))
485			continue;
486		mem_sect = __nr_to_section(section_nr);
487
488		/* same memblock ? */
489		if (mem_blk)
490			if ((section_nr >= mem_blk->start_section_nr) &&
491			    (section_nr <= mem_blk->end_section_nr))
492				continue;
493
494		mem_blk = find_memory_block_hinted(mem_sect, mem_blk);
495
496		ret = register_mem_sect_under_node(mem_blk, nid);
497		if (!err)
498			err = ret;
499
500		/* discard ref obtained in find_memory_block() */
501	}
502
503	if (mem_blk)
504		kobject_put(&mem_blk->dev.kobj);
505	return err;
506}
507
508#ifdef CONFIG_HUGETLBFS
509/*
510 * Handle per node hstate attribute [un]registration on transistions
511 * to/from memoryless state.
512 */
513static void node_hugetlb_work(struct work_struct *work)
514{
515	struct node *node = container_of(work, struct node, node_work);
516
517	/*
518	 * We only get here when a node transitions to/from memoryless state.
519	 * We can detect which transition occurred by examining whether the
520	 * node has memory now.  hugetlb_register_node() already check this
521	 * so we try to register the attributes.  If that fails, then the
522	 * node has transitioned to memoryless, try to unregister the
523	 * attributes.
524	 */
525	if (!hugetlb_register_node(node))
526		hugetlb_unregister_node(node);
527}
528
529static void init_node_hugetlb_work(int nid)
530{
531	INIT_WORK(&node_devices[nid]->node_work, node_hugetlb_work);
532}
533
534static int node_memory_callback(struct notifier_block *self,
535				unsigned long action, void *arg)
536{
537	struct memory_notify *mnb = arg;
538	int nid = mnb->status_change_nid;
539
540	switch (action) {
541	case MEM_ONLINE:
542	case MEM_OFFLINE:
543		/*
544		 * offload per node hstate [un]registration to a work thread
545		 * when transitioning to/from memoryless state.
546		 */
547		if (nid != NUMA_NO_NODE)
548			schedule_work(&node_devices[nid]->node_work);
549		break;
550
551	case MEM_GOING_ONLINE:
552	case MEM_GOING_OFFLINE:
553	case MEM_CANCEL_ONLINE:
554	case MEM_CANCEL_OFFLINE:
555	default:
556		break;
557	}
558
559	return NOTIFY_OK;
560}
561#endif	/* CONFIG_HUGETLBFS */
562#else	/* !CONFIG_MEMORY_HOTPLUG_SPARSE */
563
564static int link_mem_sections(int nid) { return 0; }
565#endif	/* CONFIG_MEMORY_HOTPLUG_SPARSE */
566
567#if !defined(CONFIG_MEMORY_HOTPLUG_SPARSE) || \
568    !defined(CONFIG_HUGETLBFS)
569static inline int node_memory_callback(struct notifier_block *self,
570				unsigned long action, void *arg)
571{
572	return NOTIFY_OK;
573}
574
575static void init_node_hugetlb_work(int nid) { }
576
577#endif
578
579int register_one_node(int nid)
580{
581	int error = 0;
582	int cpu;
583
584	if (node_online(nid)) {
585		int p_node = parent_node(nid);
586		struct node *parent = NULL;
587
588		if (p_node != nid)
589			parent = node_devices[p_node];
590
591		node_devices[nid] = kzalloc(sizeof(struct node), GFP_KERNEL);
592		if (!node_devices[nid])
593			return -ENOMEM;
594
595		error = register_node(node_devices[nid], nid, parent);
596
597		/* link cpu under this node */
598		for_each_present_cpu(cpu) {
599			if (cpu_to_node(cpu) == nid)
600				register_cpu_under_node(cpu, nid);
601		}
602
603		/* link memory sections under this node */
604		error = link_mem_sections(nid);
605
606		/* initialize work queue for memory hot plug */
607		init_node_hugetlb_work(nid);
608	}
609
610	return error;
611
612}
613
614void unregister_one_node(int nid)
615{
616	if (!node_devices[nid])
617		return;
618
619	unregister_node(node_devices[nid]);
620	node_devices[nid] = NULL;
621}
622
623/*
624 * node states attributes
625 */
626
627static ssize_t print_nodes_state(enum node_states state, char *buf)
628{
629	int n;
630
631	n = scnprintf(buf, PAGE_SIZE - 1, "%*pbl",
632		      nodemask_pr_args(&node_states[state]));
633	buf[n++] = '\n';
634	buf[n] = '\0';
 
635	return n;
636}
637
638struct node_attr {
639	struct device_attribute attr;
640	enum node_states state;
641};
642
643static ssize_t show_node_state(struct device *dev,
644			       struct device_attribute *attr, char *buf)
645{
646	struct node_attr *na = container_of(attr, struct node_attr, attr);
647	return print_nodes_state(na->state, buf);
648}
649
650#define _NODE_ATTR(name, state) \
651	{ __ATTR(name, 0444, show_node_state, NULL), state }
652
653static struct node_attr node_state_attr[] = {
654	[N_POSSIBLE] = _NODE_ATTR(possible, N_POSSIBLE),
655	[N_ONLINE] = _NODE_ATTR(online, N_ONLINE),
656	[N_NORMAL_MEMORY] = _NODE_ATTR(has_normal_memory, N_NORMAL_MEMORY),
 
657#ifdef CONFIG_HIGHMEM
658	[N_HIGH_MEMORY] = _NODE_ATTR(has_high_memory, N_HIGH_MEMORY),
659#endif
660#ifdef CONFIG_MOVABLE_NODE
661	[N_MEMORY] = _NODE_ATTR(has_memory, N_MEMORY),
662#endif
663	[N_CPU] = _NODE_ATTR(has_cpu, N_CPU),
664};
665
666static struct attribute *node_state_attrs[] = {
667	&node_state_attr[N_POSSIBLE].attr.attr,
668	&node_state_attr[N_ONLINE].attr.attr,
669	&node_state_attr[N_NORMAL_MEMORY].attr.attr,
 
670#ifdef CONFIG_HIGHMEM
671	&node_state_attr[N_HIGH_MEMORY].attr.attr,
672#endif
673#ifdef CONFIG_MOVABLE_NODE
674	&node_state_attr[N_MEMORY].attr.attr,
675#endif
676	&node_state_attr[N_CPU].attr.attr,
677	NULL
678};
679
680static struct attribute_group memory_root_attr_group = {
681	.attrs = node_state_attrs,
682};
683
684static const struct attribute_group *cpu_root_attr_groups[] = {
685	&memory_root_attr_group,
686	NULL,
687};
688
689#define NODE_CALLBACK_PRI	2	/* lower than SLAB */
690static int __init register_node_type(void)
691{
692	int ret;
693
694 	BUILD_BUG_ON(ARRAY_SIZE(node_state_attr) != NR_NODE_STATES);
695 	BUILD_BUG_ON(ARRAY_SIZE(node_state_attrs)-1 != NR_NODE_STATES);
696
697	ret = subsys_system_register(&node_subsys, cpu_root_attr_groups);
698	if (!ret) {
699		static struct notifier_block node_memory_callback_nb = {
700			.notifier_call = node_memory_callback,
701			.priority = NODE_CALLBACK_PRI,
702		};
703		register_hotmemory_notifier(&node_memory_callback_nb);
704	}
705
706	/*
707	 * Note:  we're not going to unregister the node class if we fail
708	 * to register the node state class attribute files.
709	 */
710	return ret;
711}
712postcore_initcall(register_node_type);