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v6.8
  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 const struct bus_type node_subsys = {
 25	.name = "node",
 26	.dev_name = "node",
 27};
 28
 29static inline ssize_t cpumap_read(struct file *file, struct kobject *kobj,
 30				  struct bin_attribute *attr, char *buf,
 31				  loff_t off, size_t count)
 32{
 33	struct device *dev = kobj_to_dev(kobj);
 34	struct node *node_dev = to_node(dev);
 35	cpumask_var_t mask;
 36	ssize_t n;
 37
 38	if (!alloc_cpumask_var(&mask, GFP_KERNEL))
 39		return 0;
 40
 41	cpumask_and(mask, cpumask_of_node(node_dev->dev.id), cpu_online_mask);
 42	n = cpumap_print_bitmask_to_buf(buf, mask, off, count);
 43	free_cpumask_var(mask);
 44
 45	return n;
 46}
 47
 48static BIN_ATTR_RO(cpumap, CPUMAP_FILE_MAX_BYTES);
 49
 50static inline ssize_t cpulist_read(struct file *file, struct kobject *kobj,
 51				   struct bin_attribute *attr, char *buf,
 52				   loff_t off, size_t count)
 53{
 54	struct device *dev = kobj_to_dev(kobj);
 55	struct node *node_dev = to_node(dev);
 56	cpumask_var_t mask;
 57	ssize_t n;
 58
 59	if (!alloc_cpumask_var(&mask, GFP_KERNEL))
 60		return 0;
 61
 62	cpumask_and(mask, cpumask_of_node(node_dev->dev.id), cpu_online_mask);
 63	n = cpumap_print_list_to_buf(buf, mask, off, count);
 64	free_cpumask_var(mask);
 65
 66	return n;
 67}
 68
 69static BIN_ATTR_RO(cpulist, CPULIST_FILE_MAX_BYTES);
 70
 71/**
 72 * struct node_access_nodes - Access class device to hold user visible
 73 * 			      relationships to other nodes.
 74 * @dev:	Device for this memory access class
 75 * @list_node:	List element in the node's access list
 76 * @access:	The access class rank
 77 * @coord:	Heterogeneous memory performance coordinates
 78 */
 79struct node_access_nodes {
 80	struct device		dev;
 81	struct list_head	list_node;
 82	unsigned int		access;
 83#ifdef CONFIG_HMEM_REPORTING
 84	struct access_coordinate	coord;
 85#endif
 86};
 87#define to_access_nodes(dev) container_of(dev, struct node_access_nodes, dev)
 88
 89static struct attribute *node_init_access_node_attrs[] = {
 90	NULL,
 91};
 92
 93static struct attribute *node_targ_access_node_attrs[] = {
 94	NULL,
 95};
 96
 97static const struct attribute_group initiators = {
 98	.name	= "initiators",
 99	.attrs	= node_init_access_node_attrs,
100};
101
102static const struct attribute_group targets = {
103	.name	= "targets",
104	.attrs	= node_targ_access_node_attrs,
105};
106
107static const struct attribute_group *node_access_node_groups[] = {
108	&initiators,
109	&targets,
110	NULL,
111};
112
113static void node_remove_accesses(struct node *node)
114{
115	struct node_access_nodes *c, *cnext;
116
117	list_for_each_entry_safe(c, cnext, &node->access_list, list_node) {
118		list_del(&c->list_node);
119		device_unregister(&c->dev);
120	}
121}
122
123static void node_access_release(struct device *dev)
124{
125	kfree(to_access_nodes(dev));
126}
127
128static struct node_access_nodes *node_init_node_access(struct node *node,
129						       unsigned int access)
130{
131	struct node_access_nodes *access_node;
132	struct device *dev;
133
134	list_for_each_entry(access_node, &node->access_list, list_node)
135		if (access_node->access == access)
136			return access_node;
137
138	access_node = kzalloc(sizeof(*access_node), GFP_KERNEL);
139	if (!access_node)
140		return NULL;
141
142	access_node->access = access;
143	dev = &access_node->dev;
144	dev->parent = &node->dev;
145	dev->release = node_access_release;
146	dev->groups = node_access_node_groups;
147	if (dev_set_name(dev, "access%u", access))
148		goto free;
149
150	if (device_register(dev))
151		goto free_name;
152
153	pm_runtime_no_callbacks(dev);
154	list_add_tail(&access_node->list_node, &node->access_list);
155	return access_node;
156free_name:
157	kfree_const(dev->kobj.name);
158free:
159	kfree(access_node);
160	return NULL;
161}
162
163#ifdef CONFIG_HMEM_REPORTING
164#define ACCESS_ATTR(property)						\
165static ssize_t property##_show(struct device *dev,			\
166			   struct device_attribute *attr,		\
167			   char *buf)					\
168{									\
169	return sysfs_emit(buf, "%u\n",					\
170			  to_access_nodes(dev)->coord.property);	\
171}									\
172static DEVICE_ATTR_RO(property)
173
174ACCESS_ATTR(read_bandwidth);
175ACCESS_ATTR(read_latency);
176ACCESS_ATTR(write_bandwidth);
177ACCESS_ATTR(write_latency);
178
179static struct attribute *access_attrs[] = {
180	&dev_attr_read_bandwidth.attr,
181	&dev_attr_read_latency.attr,
182	&dev_attr_write_bandwidth.attr,
183	&dev_attr_write_latency.attr,
184	NULL,
185};
186
187/**
188 * node_set_perf_attrs - Set the performance values for given access class
189 * @nid: Node identifier to be set
190 * @coord: Heterogeneous memory performance coordinates
191 * @access: The access class the for the given attributes
192 */
193void node_set_perf_attrs(unsigned int nid, struct access_coordinate *coord,
194			 unsigned int access)
195{
196	struct node_access_nodes *c;
197	struct node *node;
198	int i;
199
200	if (WARN_ON_ONCE(!node_online(nid)))
201		return;
202
203	node = node_devices[nid];
204	c = node_init_node_access(node, access);
205	if (!c)
206		return;
207
208	c->coord = *coord;
209	for (i = 0; access_attrs[i] != NULL; i++) {
210		if (sysfs_add_file_to_group(&c->dev.kobj, access_attrs[i],
211					    "initiators")) {
212			pr_info("failed to add performance attribute to node %d\n",
213				nid);
214			break;
215		}
216	}
217}
218
219/**
220 * struct node_cache_info - Internal tracking for memory node caches
221 * @dev:	Device represeting the cache level
222 * @node:	List element for tracking in the node
223 * @cache_attrs:Attributes for this cache level
224 */
225struct node_cache_info {
226	struct device dev;
227	struct list_head node;
228	struct node_cache_attrs cache_attrs;
229};
230#define to_cache_info(device) container_of(device, struct node_cache_info, dev)
231
232#define CACHE_ATTR(name, fmt) 						\
233static ssize_t name##_show(struct device *dev,				\
234			   struct device_attribute *attr,		\
235			   char *buf)					\
236{									\
237	return sysfs_emit(buf, fmt "\n",				\
238			  to_cache_info(dev)->cache_attrs.name);	\
239}									\
240static DEVICE_ATTR_RO(name);
241
242CACHE_ATTR(size, "%llu")
243CACHE_ATTR(line_size, "%u")
244CACHE_ATTR(indexing, "%u")
245CACHE_ATTR(write_policy, "%u")
246
247static struct attribute *cache_attrs[] = {
248	&dev_attr_indexing.attr,
249	&dev_attr_size.attr,
250	&dev_attr_line_size.attr,
251	&dev_attr_write_policy.attr,
252	NULL,
253};
254ATTRIBUTE_GROUPS(cache);
255
256static void node_cache_release(struct device *dev)
257{
258	kfree(dev);
259}
260
261static void node_cacheinfo_release(struct device *dev)
262{
263	struct node_cache_info *info = to_cache_info(dev);
264	kfree(info);
265}
266
267static void node_init_cache_dev(struct node *node)
268{
269	struct device *dev;
270
271	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
272	if (!dev)
273		return;
274
275	device_initialize(dev);
276	dev->parent = &node->dev;
277	dev->release = node_cache_release;
278	if (dev_set_name(dev, "memory_side_cache"))
279		goto put_device;
280
281	if (device_add(dev))
282		goto put_device;
283
284	pm_runtime_no_callbacks(dev);
285	node->cache_dev = dev;
286	return;
287put_device:
288	put_device(dev);
289}
290
291/**
292 * node_add_cache() - add cache attribute to a memory node
293 * @nid: Node identifier that has new cache attributes
294 * @cache_attrs: Attributes for the cache being added
295 */
296void node_add_cache(unsigned int nid, struct node_cache_attrs *cache_attrs)
297{
298	struct node_cache_info *info;
299	struct device *dev;
300	struct node *node;
301
302	if (!node_online(nid) || !node_devices[nid])
303		return;
304
305	node = node_devices[nid];
306	list_for_each_entry(info, &node->cache_attrs, node) {
307		if (info->cache_attrs.level == cache_attrs->level) {
308			dev_warn(&node->dev,
309				"attempt to add duplicate cache level:%d\n",
310				cache_attrs->level);
311			return;
312		}
313	}
314
315	if (!node->cache_dev)
316		node_init_cache_dev(node);
317	if (!node->cache_dev)
318		return;
319
320	info = kzalloc(sizeof(*info), GFP_KERNEL);
321	if (!info)
322		return;
323
324	dev = &info->dev;
325	device_initialize(dev);
326	dev->parent = node->cache_dev;
327	dev->release = node_cacheinfo_release;
328	dev->groups = cache_groups;
329	if (dev_set_name(dev, "index%d", cache_attrs->level))
330		goto put_device;
331
332	info->cache_attrs = *cache_attrs;
333	if (device_add(dev)) {
334		dev_warn(&node->dev, "failed to add cache level:%d\n",
335			 cache_attrs->level);
336		goto put_device;
337	}
338	pm_runtime_no_callbacks(dev);
339	list_add_tail(&info->node, &node->cache_attrs);
340	return;
341put_device:
342	put_device(dev);
343}
344
345static void node_remove_caches(struct node *node)
346{
347	struct node_cache_info *info, *next;
348
349	if (!node->cache_dev)
350		return;
351
352	list_for_each_entry_safe(info, next, &node->cache_attrs, node) {
353		list_del(&info->node);
354		device_unregister(&info->dev);
355	}
356	device_unregister(node->cache_dev);
357}
358
359static void node_init_caches(unsigned int nid)
360{
361	INIT_LIST_HEAD(&node_devices[nid]->cache_attrs);
362}
363#else
364static void node_init_caches(unsigned int nid) { }
365static void node_remove_caches(struct node *node) { }
366#endif
367
368#define K(x) ((x) << (PAGE_SHIFT - 10))
369static ssize_t node_read_meminfo(struct device *dev,
370			struct device_attribute *attr, char *buf)
371{
372	int len = 0;
373	int nid = dev->id;
374	struct pglist_data *pgdat = NODE_DATA(nid);
375	struct sysinfo i;
376	unsigned long sreclaimable, sunreclaimable;
377	unsigned long swapcached = 0;
378
379	si_meminfo_node(&i, nid);
380	sreclaimable = node_page_state_pages(pgdat, NR_SLAB_RECLAIMABLE_B);
381	sunreclaimable = node_page_state_pages(pgdat, NR_SLAB_UNRECLAIMABLE_B);
382#ifdef CONFIG_SWAP
383	swapcached = node_page_state_pages(pgdat, NR_SWAPCACHE);
384#endif
385	len = sysfs_emit_at(buf, len,
386			    "Node %d MemTotal:       %8lu kB\n"
387			    "Node %d MemFree:        %8lu kB\n"
388			    "Node %d MemUsed:        %8lu kB\n"
389			    "Node %d SwapCached:     %8lu kB\n"
390			    "Node %d Active:         %8lu kB\n"
391			    "Node %d Inactive:       %8lu kB\n"
392			    "Node %d Active(anon):   %8lu kB\n"
393			    "Node %d Inactive(anon): %8lu kB\n"
394			    "Node %d Active(file):   %8lu kB\n"
395			    "Node %d Inactive(file): %8lu kB\n"
396			    "Node %d Unevictable:    %8lu kB\n"
397			    "Node %d Mlocked:        %8lu kB\n",
398			    nid, K(i.totalram),
399			    nid, K(i.freeram),
400			    nid, K(i.totalram - i.freeram),
401			    nid, K(swapcached),
402			    nid, K(node_page_state(pgdat, NR_ACTIVE_ANON) +
403				   node_page_state(pgdat, NR_ACTIVE_FILE)),
404			    nid, K(node_page_state(pgdat, NR_INACTIVE_ANON) +
405				   node_page_state(pgdat, NR_INACTIVE_FILE)),
406			    nid, K(node_page_state(pgdat, NR_ACTIVE_ANON)),
407			    nid, K(node_page_state(pgdat, NR_INACTIVE_ANON)),
408			    nid, K(node_page_state(pgdat, NR_ACTIVE_FILE)),
409			    nid, K(node_page_state(pgdat, NR_INACTIVE_FILE)),
410			    nid, K(node_page_state(pgdat, NR_UNEVICTABLE)),
411			    nid, K(sum_zone_node_page_state(nid, NR_MLOCK)));
412
413#ifdef CONFIG_HIGHMEM
414	len += sysfs_emit_at(buf, len,
415			     "Node %d HighTotal:      %8lu kB\n"
416			     "Node %d HighFree:       %8lu kB\n"
417			     "Node %d LowTotal:       %8lu kB\n"
418			     "Node %d LowFree:        %8lu kB\n",
419			     nid, K(i.totalhigh),
420			     nid, K(i.freehigh),
421			     nid, K(i.totalram - i.totalhigh),
422			     nid, K(i.freeram - i.freehigh));
423#endif
424	len += sysfs_emit_at(buf, len,
425			     "Node %d Dirty:          %8lu kB\n"
426			     "Node %d Writeback:      %8lu kB\n"
427			     "Node %d FilePages:      %8lu kB\n"
428			     "Node %d Mapped:         %8lu kB\n"
429			     "Node %d AnonPages:      %8lu kB\n"
430			     "Node %d Shmem:          %8lu kB\n"
431			     "Node %d KernelStack:    %8lu kB\n"
432#ifdef CONFIG_SHADOW_CALL_STACK
433			     "Node %d ShadowCallStack:%8lu kB\n"
434#endif
435			     "Node %d PageTables:     %8lu kB\n"
436			     "Node %d SecPageTables:  %8lu kB\n"
437			     "Node %d NFS_Unstable:   %8lu kB\n"
438			     "Node %d Bounce:         %8lu kB\n"
439			     "Node %d WritebackTmp:   %8lu kB\n"
440			     "Node %d KReclaimable:   %8lu kB\n"
441			     "Node %d Slab:           %8lu kB\n"
442			     "Node %d SReclaimable:   %8lu kB\n"
443			     "Node %d SUnreclaim:     %8lu kB\n"
444#ifdef CONFIG_TRANSPARENT_HUGEPAGE
445			     "Node %d AnonHugePages:  %8lu kB\n"
446			     "Node %d ShmemHugePages: %8lu kB\n"
447			     "Node %d ShmemPmdMapped: %8lu kB\n"
448			     "Node %d FileHugePages:  %8lu kB\n"
449			     "Node %d FilePmdMapped:  %8lu kB\n"
450#endif
451#ifdef CONFIG_UNACCEPTED_MEMORY
452			     "Node %d Unaccepted:     %8lu kB\n"
453#endif
454			     ,
455			     nid, K(node_page_state(pgdat, NR_FILE_DIRTY)),
456			     nid, K(node_page_state(pgdat, NR_WRITEBACK)),
457			     nid, K(node_page_state(pgdat, NR_FILE_PAGES)),
458			     nid, K(node_page_state(pgdat, NR_FILE_MAPPED)),
459			     nid, K(node_page_state(pgdat, NR_ANON_MAPPED)),
460			     nid, K(i.sharedram),
461			     nid, node_page_state(pgdat, NR_KERNEL_STACK_KB),
462#ifdef CONFIG_SHADOW_CALL_STACK
463			     nid, node_page_state(pgdat, NR_KERNEL_SCS_KB),
464#endif
465			     nid, K(node_page_state(pgdat, NR_PAGETABLE)),
466			     nid, K(node_page_state(pgdat, NR_SECONDARY_PAGETABLE)),
467			     nid, 0UL,
468			     nid, K(sum_zone_node_page_state(nid, NR_BOUNCE)),
469			     nid, K(node_page_state(pgdat, NR_WRITEBACK_TEMP)),
470			     nid, K(sreclaimable +
471				    node_page_state(pgdat, NR_KERNEL_MISC_RECLAIMABLE)),
472			     nid, K(sreclaimable + sunreclaimable),
473			     nid, K(sreclaimable),
474			     nid, K(sunreclaimable)
475#ifdef CONFIG_TRANSPARENT_HUGEPAGE
476			     ,
477			     nid, K(node_page_state(pgdat, NR_ANON_THPS)),
478			     nid, K(node_page_state(pgdat, NR_SHMEM_THPS)),
479			     nid, K(node_page_state(pgdat, NR_SHMEM_PMDMAPPED)),
480			     nid, K(node_page_state(pgdat, NR_FILE_THPS)),
481			     nid, K(node_page_state(pgdat, NR_FILE_PMDMAPPED))
482#endif
483#ifdef CONFIG_UNACCEPTED_MEMORY
484			     ,
485			     nid, K(sum_zone_node_page_state(nid, NR_UNACCEPTED))
 
 
 
 
 
 
 
 
 
 
 
 
 
 
486#endif
487			    );
488	len += hugetlb_report_node_meminfo(buf, len, nid);
489	return len;
490}
491
492#undef K
493static DEVICE_ATTR(meminfo, 0444, node_read_meminfo, NULL);
494
495static ssize_t node_read_numastat(struct device *dev,
496				  struct device_attribute *attr, char *buf)
497{
498	fold_vm_numa_events();
499	return sysfs_emit(buf,
500			  "numa_hit %lu\n"
501			  "numa_miss %lu\n"
502			  "numa_foreign %lu\n"
503			  "interleave_hit %lu\n"
504			  "local_node %lu\n"
505			  "other_node %lu\n",
506			  sum_zone_numa_event_state(dev->id, NUMA_HIT),
507			  sum_zone_numa_event_state(dev->id, NUMA_MISS),
508			  sum_zone_numa_event_state(dev->id, NUMA_FOREIGN),
509			  sum_zone_numa_event_state(dev->id, NUMA_INTERLEAVE_HIT),
510			  sum_zone_numa_event_state(dev->id, NUMA_LOCAL),
511			  sum_zone_numa_event_state(dev->id, NUMA_OTHER));
512}
513static DEVICE_ATTR(numastat, 0444, node_read_numastat, NULL);
514
515static ssize_t node_read_vmstat(struct device *dev,
516				struct device_attribute *attr, char *buf)
517{
518	int nid = dev->id;
519	struct pglist_data *pgdat = NODE_DATA(nid);
520	int i;
521	int len = 0;
522
523	for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
524		len += sysfs_emit_at(buf, len, "%s %lu\n",
525				     zone_stat_name(i),
526				     sum_zone_node_page_state(nid, i));
527
528#ifdef CONFIG_NUMA
529	fold_vm_numa_events();
530	for (i = 0; i < NR_VM_NUMA_EVENT_ITEMS; i++)
531		len += sysfs_emit_at(buf, len, "%s %lu\n",
532				     numa_stat_name(i),
533				     sum_zone_numa_event_state(nid, i));
534
535#endif
536	for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) {
537		unsigned long pages = node_page_state_pages(pgdat, i);
538
539		if (vmstat_item_print_in_thp(i))
540			pages /= HPAGE_PMD_NR;
541		len += sysfs_emit_at(buf, len, "%s %lu\n", node_stat_name(i),
542				     pages);
543	}
544
545	return len;
546}
547static DEVICE_ATTR(vmstat, 0444, node_read_vmstat, NULL);
548
549static ssize_t node_read_distance(struct device *dev,
550				  struct device_attribute *attr, char *buf)
551{
552	int nid = dev->id;
553	int len = 0;
554	int i;
555
556	/*
557	 * buf is currently PAGE_SIZE in length and each node needs 4 chars
558	 * at the most (distance + space or newline).
559	 */
560	BUILD_BUG_ON(MAX_NUMNODES * 4 > PAGE_SIZE);
561
562	for_each_online_node(i) {
563		len += sysfs_emit_at(buf, len, "%s%d",
564				     i ? " " : "", node_distance(nid, i));
565	}
566
567	len += sysfs_emit_at(buf, len, "\n");
568	return len;
569}
570static DEVICE_ATTR(distance, 0444, node_read_distance, NULL);
571
572static struct attribute *node_dev_attrs[] = {
573	&dev_attr_meminfo.attr,
574	&dev_attr_numastat.attr,
575	&dev_attr_distance.attr,
576	&dev_attr_vmstat.attr,
577	NULL
578};
579
580static struct bin_attribute *node_dev_bin_attrs[] = {
581	&bin_attr_cpumap,
582	&bin_attr_cpulist,
583	NULL
584};
585
586static const struct attribute_group node_dev_group = {
587	.attrs = node_dev_attrs,
588	.bin_attrs = node_dev_bin_attrs
589};
 
 
 
 
 
590
591static const struct attribute_group *node_dev_groups[] = {
592	&node_dev_group,
593#ifdef CONFIG_HAVE_ARCH_NODE_DEV_GROUP
594	&arch_node_dev_group,
595#endif
596#ifdef CONFIG_MEMORY_FAILURE
597	&memory_failure_attr_group,
598#endif
599	NULL
600};
601
602static void node_device_release(struct device *dev)
 
603{
604	kfree(to_node(dev));
 
605}
 
 
 
 
 
 
606
607/*
608 * register_node - Setup a sysfs device for a node.
609 * @num - Node number to use when creating the device.
610 *
611 * Initialize and register the node device.
612 */
613static int register_node(struct node *node, int num)
614{
615	int error;
616
617	node->dev.id = num;
618	node->dev.bus = &node_subsys;
619	node->dev.release = node_device_release;
620	node->dev.groups = node_dev_groups;
621	error = device_register(&node->dev);
622
623	if (error) {
624		put_device(&node->dev);
625	} else {
 
 
 
 
 
 
 
626		hugetlb_register_node(node);
 
627		compaction_register_node(node);
628	}
629
630	return error;
631}
632
633/**
634 * unregister_node - unregister a node device
635 * @node: node going away
636 *
637 * Unregisters a node device @node.  All the devices on the node must be
638 * unregistered before calling this function.
639 */
640void unregister_node(struct node *node)
641{
642	hugetlb_unregister_node(node);
643	compaction_unregister_node(node);
644	node_remove_accesses(node);
645	node_remove_caches(node);
 
 
 
 
 
 
646	device_unregister(&node->dev);
647}
648
649struct node *node_devices[MAX_NUMNODES];
650
651/*
652 * register cpu under node
653 */
654int register_cpu_under_node(unsigned int cpu, unsigned int nid)
655{
656	int ret;
657	struct device *obj;
658
659	if (!node_online(nid))
660		return 0;
661
662	obj = get_cpu_device(cpu);
663	if (!obj)
664		return 0;
665
666	ret = sysfs_create_link(&node_devices[nid]->dev.kobj,
667				&obj->kobj,
668				kobject_name(&obj->kobj));
669	if (ret)
670		return ret;
671
672	return sysfs_create_link(&obj->kobj,
673				 &node_devices[nid]->dev.kobj,
674				 kobject_name(&node_devices[nid]->dev.kobj));
675}
676
677/**
678 * register_memory_node_under_compute_node - link memory node to its compute
679 *					     node for a given access class.
680 * @mem_nid:	Memory node number
681 * @cpu_nid:	Cpu  node number
682 * @access:	Access class to register
683 *
684 * Description:
685 * 	For use with platforms that may have separate memory and compute nodes.
686 * 	This function will export node relationships linking which memory
687 * 	initiator nodes can access memory targets at a given ranked access
688 * 	class.
689 */
690int register_memory_node_under_compute_node(unsigned int mem_nid,
691					    unsigned int cpu_nid,
692					    unsigned int access)
693{
694	struct node *init_node, *targ_node;
695	struct node_access_nodes *initiator, *target;
696	int ret;
697
698	if (!node_online(cpu_nid) || !node_online(mem_nid))
699		return -ENODEV;
700
701	init_node = node_devices[cpu_nid];
702	targ_node = node_devices[mem_nid];
703	initiator = node_init_node_access(init_node, access);
704	target = node_init_node_access(targ_node, access);
705	if (!initiator || !target)
706		return -ENOMEM;
707
708	ret = sysfs_add_link_to_group(&initiator->dev.kobj, "targets",
709				      &targ_node->dev.kobj,
710				      dev_name(&targ_node->dev));
711	if (ret)
712		return ret;
713
714	ret = sysfs_add_link_to_group(&target->dev.kobj, "initiators",
715				      &init_node->dev.kobj,
716				      dev_name(&init_node->dev));
717	if (ret)
718		goto err;
719
720	return 0;
721 err:
722	sysfs_remove_link_from_group(&initiator->dev.kobj, "targets",
723				     dev_name(&targ_node->dev));
724	return ret;
725}
726
727int unregister_cpu_under_node(unsigned int cpu, unsigned int nid)
728{
729	struct device *obj;
730
731	if (!node_online(nid))
732		return 0;
733
734	obj = get_cpu_device(cpu);
735	if (!obj)
736		return 0;
737
738	sysfs_remove_link(&node_devices[nid]->dev.kobj,
739			  kobject_name(&obj->kobj));
740	sysfs_remove_link(&obj->kobj,
741			  kobject_name(&node_devices[nid]->dev.kobj));
742
743	return 0;
744}
745
746#ifdef CONFIG_MEMORY_HOTPLUG
747static int __ref get_nid_for_pfn(unsigned long pfn)
748{
749#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
750	if (system_state < SYSTEM_RUNNING)
751		return early_pfn_to_nid(pfn);
752#endif
753	return pfn_to_nid(pfn);
754}
755
756static void do_register_memory_block_under_node(int nid,
757						struct memory_block *mem_blk,
758						enum meminit_context context)
759{
760	int ret;
761
762	memory_block_add_nid(mem_blk, nid, context);
763
764	ret = sysfs_create_link_nowarn(&node_devices[nid]->dev.kobj,
765				       &mem_blk->dev.kobj,
766				       kobject_name(&mem_blk->dev.kobj));
767	if (ret && ret != -EEXIST)
768		dev_err_ratelimited(&node_devices[nid]->dev,
769				    "can't create link to %s in sysfs (%d)\n",
770				    kobject_name(&mem_blk->dev.kobj), ret);
771
772	ret = sysfs_create_link_nowarn(&mem_blk->dev.kobj,
773				&node_devices[nid]->dev.kobj,
774				kobject_name(&node_devices[nid]->dev.kobj));
775	if (ret && ret != -EEXIST)
776		dev_err_ratelimited(&mem_blk->dev,
777				    "can't create link to %s in sysfs (%d)\n",
778				    kobject_name(&node_devices[nid]->dev.kobj),
779				    ret);
780}
781
782/* register memory section under specified node if it spans that node */
783static int register_mem_block_under_node_early(struct memory_block *mem_blk,
784					       void *arg)
785{
786	unsigned long memory_block_pfns = memory_block_size_bytes() / PAGE_SIZE;
787	unsigned long start_pfn = section_nr_to_pfn(mem_blk->start_section_nr);
788	unsigned long end_pfn = start_pfn + memory_block_pfns - 1;
789	int nid = *(int *)arg;
790	unsigned long pfn;
791
792	for (pfn = start_pfn; pfn <= end_pfn; pfn++) {
793		int page_nid;
 
 
794
795		/*
796		 * memory block could have several absent sections from start.
797		 * skip pfn range from absent section
798		 */
799		if (!pfn_in_present_section(pfn)) {
800			pfn = round_down(pfn + PAGES_PER_SECTION,
801					 PAGES_PER_SECTION) - 1;
802			continue;
803		}
804
805		/*
806		 * We need to check if page belongs to nid only at the boot
807		 * case because node's ranges can be interleaved.
808		 */
809		page_nid = get_nid_for_pfn(pfn);
810		if (page_nid < 0)
811			continue;
812		if (page_nid != nid)
813			continue;
 
 
 
 
 
814
815		do_register_memory_block_under_node(nid, mem_blk, MEMINIT_EARLY);
816		return 0;
 
817	}
818	/* mem section does not span the specified node */
819	return 0;
820}
821
822/*
823 * During hotplug we know that all pages in the memory block belong to the same
824 * node.
825 */
826static int register_mem_block_under_node_hotplug(struct memory_block *mem_blk,
827						 void *arg)
828{
829	int nid = *(int *)arg;
 
 
 
 
 
 
 
 
 
 
 
830
831	do_register_memory_block_under_node(nid, mem_blk, MEMINIT_HOTPLUG);
 
 
 
 
 
 
 
 
 
 
 
 
832	return 0;
833}
834
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
835/*
836 * Unregister a memory block device under the node it spans. Memory blocks
837 * with multiple nodes cannot be offlined and therefore also never be removed.
838 */
839void unregister_memory_block_under_nodes(struct memory_block *mem_blk)
840{
841	if (mem_blk->nid == NUMA_NO_NODE)
842		return;
843
844	sysfs_remove_link(&node_devices[mem_blk->nid]->dev.kobj,
845			  kobject_name(&mem_blk->dev.kobj));
846	sysfs_remove_link(&mem_blk->dev.kobj,
847			  kobject_name(&node_devices[mem_blk->nid]->dev.kobj));
 
 
 
 
 
 
848}
849
850void register_memory_blocks_under_node(int nid, unsigned long start_pfn,
851				       unsigned long end_pfn,
852				       enum meminit_context context)
853{
854	walk_memory_blocks_func_t func;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
855
856	if (context == MEMINIT_HOTPLUG)
857		func = register_mem_block_under_node_hotplug;
858	else
859		func = register_mem_block_under_node_early;
 
 
 
860
861	walk_memory_blocks(PFN_PHYS(start_pfn), PFN_PHYS(end_pfn - start_pfn),
862			   (void *)&nid, func);
863	return;
864}
865#endif /* CONFIG_MEMORY_HOTPLUG */
 
 
 
 
866
867int __register_one_node(int nid)
 
 
 
868{
869	int error;
870	int cpu;
871	struct node *node;
872
873	node = kzalloc(sizeof(struct node), GFP_KERNEL);
874	if (!node)
875		return -ENOMEM;
876
877	INIT_LIST_HEAD(&node->access_list);
878	node_devices[nid] = node;
879
880	error = register_node(node_devices[nid], nid);
 
 
 
881
882	/* link cpu under this node */
883	for_each_present_cpu(cpu) {
884		if (cpu_to_node(cpu) == nid)
885			register_cpu_under_node(cpu, nid);
886	}
 
 
 
 
 
 
 
 
 
 
 
 
887
888	node_init_caches(nid);
 
 
889
890	return error;
 
891}
892
893void unregister_one_node(int nid)
894{
895	if (!node_devices[nid])
896		return;
897
898	unregister_node(node_devices[nid]);
899	node_devices[nid] = NULL;
900}
901
902/*
903 * node states attributes
904 */
905
 
 
 
 
 
 
 
 
 
 
906struct node_attr {
907	struct device_attribute attr;
908	enum node_states state;
909};
910
911static ssize_t show_node_state(struct device *dev,
912			       struct device_attribute *attr, char *buf)
913{
914	struct node_attr *na = container_of(attr, struct node_attr, attr);
915
916	return sysfs_emit(buf, "%*pbl\n",
917			  nodemask_pr_args(&node_states[na->state]));
918}
919
920#define _NODE_ATTR(name, state) \
921	{ __ATTR(name, 0444, show_node_state, NULL), state }
922
923static struct node_attr node_state_attr[] = {
924	[N_POSSIBLE] = _NODE_ATTR(possible, N_POSSIBLE),
925	[N_ONLINE] = _NODE_ATTR(online, N_ONLINE),
926	[N_NORMAL_MEMORY] = _NODE_ATTR(has_normal_memory, N_NORMAL_MEMORY),
 
927#ifdef CONFIG_HIGHMEM
928	[N_HIGH_MEMORY] = _NODE_ATTR(has_high_memory, N_HIGH_MEMORY),
929#endif
930	[N_MEMORY] = _NODE_ATTR(has_memory, N_MEMORY),
931	[N_CPU] = _NODE_ATTR(has_cpu, N_CPU),
932	[N_GENERIC_INITIATOR] = _NODE_ATTR(has_generic_initiator,
933					   N_GENERIC_INITIATOR),
934};
935
936static struct attribute *node_state_attrs[] = {
937	&node_state_attr[N_POSSIBLE].attr.attr,
938	&node_state_attr[N_ONLINE].attr.attr,
939	&node_state_attr[N_NORMAL_MEMORY].attr.attr,
 
940#ifdef CONFIG_HIGHMEM
941	&node_state_attr[N_HIGH_MEMORY].attr.attr,
942#endif
943	&node_state_attr[N_MEMORY].attr.attr,
944	&node_state_attr[N_CPU].attr.attr,
945	&node_state_attr[N_GENERIC_INITIATOR].attr.attr,
946	NULL
947};
948
949static const struct attribute_group memory_root_attr_group = {
950	.attrs = node_state_attrs,
951};
952
953static const struct attribute_group *cpu_root_attr_groups[] = {
954	&memory_root_attr_group,
955	NULL,
956};
957
958void __init node_dev_init(void)
 
959{
960	int ret, i;
961
962 	BUILD_BUG_ON(ARRAY_SIZE(node_state_attr) != NR_NODE_STATES);
963 	BUILD_BUG_ON(ARRAY_SIZE(node_state_attrs)-1 != NR_NODE_STATES);
964
965	ret = subsys_system_register(&node_subsys, cpu_root_attr_groups);
966	if (ret)
967		panic("%s() failed to register subsystem: %d\n", __func__, ret);
 
 
968
969	/*
970	 * Create all node devices, which will properly link the node
971	 * to applicable memory block devices and already created cpu devices.
972	 */
973	for_each_online_node(i) {
974		ret = register_one_node(i);
975		if (ret)
976			panic("%s() failed to add node: %d\n", __func__, ret);
977	}
978}
v3.5.6
 
  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/node.h>
 11#include <linux/hugetlb.h>
 12#include <linux/compaction.h>
 13#include <linux/cpumask.h>
 14#include <linux/topology.h>
 15#include <linux/nodemask.h>
 16#include <linux/cpu.h>
 17#include <linux/device.h>
 
 18#include <linux/swap.h>
 19#include <linux/slab.h>
 20
 21static struct bus_type node_subsys = {
 22	.name = "node",
 23	.dev_name = "node",
 24};
 25
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 26
 27static ssize_t node_read_cpumap(struct device *dev, int type, char *buf)
 
 
 
 
 28{
 
 29	struct node *node_dev = to_node(dev);
 30	const struct cpumask *mask = cpumask_of_node(node_dev->dev.id);
 31	int len;
 
 
 
 
 
 
 
 
 
 
 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	len = type?
 37		cpulist_scnprintf(buf, PAGE_SIZE-2, mask) :
 38		cpumask_scnprintf(buf, PAGE_SIZE-2, mask);
 39 	buf[len++] = '\n';
 40 	buf[len] = '\0';
 41	return len;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 42}
 43
 44static inline ssize_t node_read_cpumask(struct device *dev,
 45				struct device_attribute *attr, char *buf)
 
 
 
 
 46{
 47	return node_read_cpumap(dev, 0, buf);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 48}
 49static inline ssize_t node_read_cpulist(struct device *dev,
 50				struct device_attribute *attr, char *buf)
 51{
 52	return node_read_cpumap(dev, 1, buf);
 
 
 
 
 
 
 
 
 
 53}
 54
 55static DEVICE_ATTR(cpumap,  S_IRUGO, node_read_cpumask, NULL);
 56static DEVICE_ATTR(cpulist, S_IRUGO, node_read_cpulist, NULL);
 
 
 
 
 
 
 57
 58#define K(x) ((x) << (PAGE_SHIFT - 10))
 59static ssize_t node_read_meminfo(struct device *dev,
 60			struct device_attribute *attr, char *buf)
 61{
 62	int n;
 63	int nid = dev->id;
 
 64	struct sysinfo i;
 
 
 65
 66	si_meminfo_node(&i, nid);
 67	n = sprintf(buf,
 68		       "Node %d MemTotal:       %8lu kB\n"
 69		       "Node %d MemFree:        %8lu kB\n"
 70		       "Node %d MemUsed:        %8lu kB\n"
 71		       "Node %d Active:         %8lu kB\n"
 72		       "Node %d Inactive:       %8lu kB\n"
 73		       "Node %d Active(anon):   %8lu kB\n"
 74		       "Node %d Inactive(anon): %8lu kB\n"
 75		       "Node %d Active(file):   %8lu kB\n"
 76		       "Node %d Inactive(file): %8lu kB\n"
 77		       "Node %d Unevictable:    %8lu kB\n"
 78		       "Node %d Mlocked:        %8lu kB\n",
 79		       nid, K(i.totalram),
 80		       nid, K(i.freeram),
 81		       nid, K(i.totalram - i.freeram),
 82		       nid, K(node_page_state(nid, NR_ACTIVE_ANON) +
 83				node_page_state(nid, NR_ACTIVE_FILE)),
 84		       nid, K(node_page_state(nid, NR_INACTIVE_ANON) +
 85				node_page_state(nid, NR_INACTIVE_FILE)),
 86		       nid, K(node_page_state(nid, NR_ACTIVE_ANON)),
 87		       nid, K(node_page_state(nid, NR_INACTIVE_ANON)),
 88		       nid, K(node_page_state(nid, NR_ACTIVE_FILE)),
 89		       nid, K(node_page_state(nid, NR_INACTIVE_FILE)),
 90		       nid, K(node_page_state(nid, NR_UNEVICTABLE)),
 91		       nid, K(node_page_state(nid, NR_MLOCK)));
 
 
 
 
 
 
 
 92
 93#ifdef CONFIG_HIGHMEM
 94	n += sprintf(buf + n,
 95		       "Node %d HighTotal:      %8lu kB\n"
 96		       "Node %d HighFree:       %8lu kB\n"
 97		       "Node %d LowTotal:       %8lu kB\n"
 98		       "Node %d LowFree:        %8lu kB\n",
 99		       nid, K(i.totalhigh),
100		       nid, K(i.freehigh),
101		       nid, K(i.totalram - i.totalhigh),
102		       nid, K(i.freeram - i.freehigh));
103#endif
104	n += sprintf(buf + n,
105		       "Node %d Dirty:          %8lu kB\n"
106		       "Node %d Writeback:      %8lu kB\n"
107		       "Node %d FilePages:      %8lu kB\n"
108		       "Node %d Mapped:         %8lu kB\n"
109		       "Node %d AnonPages:      %8lu kB\n"
110		       "Node %d Shmem:          %8lu kB\n"
111		       "Node %d KernelStack:    %8lu kB\n"
112		       "Node %d PageTables:     %8lu kB\n"
113		       "Node %d NFS_Unstable:   %8lu kB\n"
114		       "Node %d Bounce:         %8lu kB\n"
115		       "Node %d WritebackTmp:   %8lu kB\n"
116		       "Node %d Slab:           %8lu kB\n"
117		       "Node %d SReclaimable:   %8lu kB\n"
118		       "Node %d SUnreclaim:     %8lu kB\n"
 
 
 
 
 
119#ifdef CONFIG_TRANSPARENT_HUGEPAGE
120		       "Node %d AnonHugePages:  %8lu kB\n"
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
121#endif
122			,
123		       nid, K(node_page_state(nid, NR_FILE_DIRTY)),
124		       nid, K(node_page_state(nid, NR_WRITEBACK)),
125		       nid, K(node_page_state(nid, NR_FILE_PAGES)),
126		       nid, K(node_page_state(nid, NR_FILE_MAPPED)),
 
 
 
 
 
127#ifdef CONFIG_TRANSPARENT_HUGEPAGE
128		       nid, K(node_page_state(nid, NR_ANON_PAGES)
129			+ node_page_state(nid, NR_ANON_TRANSPARENT_HUGEPAGES) *
130			HPAGE_PMD_NR),
131#else
132		       nid, K(node_page_state(nid, NR_ANON_PAGES)),
 
133#endif
134		       nid, K(node_page_state(nid, NR_SHMEM)),
135		       nid, node_page_state(nid, NR_KERNEL_STACK) *
136				THREAD_SIZE / 1024,
137		       nid, K(node_page_state(nid, NR_PAGETABLE)),
138		       nid, K(node_page_state(nid, NR_UNSTABLE_NFS)),
139		       nid, K(node_page_state(nid, NR_BOUNCE)),
140		       nid, K(node_page_state(nid, NR_WRITEBACK_TEMP)),
141		       nid, K(node_page_state(nid, NR_SLAB_RECLAIMABLE) +
142				node_page_state(nid, NR_SLAB_UNRECLAIMABLE)),
143		       nid, K(node_page_state(nid, NR_SLAB_RECLAIMABLE)),
144#ifdef CONFIG_TRANSPARENT_HUGEPAGE
145		       nid, K(node_page_state(nid, NR_SLAB_UNRECLAIMABLE))
146			, nid,
147			K(node_page_state(nid, NR_ANON_TRANSPARENT_HUGEPAGES) *
148			HPAGE_PMD_NR));
149#else
150		       nid, K(node_page_state(nid, NR_SLAB_UNRECLAIMABLE)));
151#endif
152	n += hugetlb_report_node_meminfo(nid, buf + n);
153	return n;
 
154}
155
156#undef K
157static DEVICE_ATTR(meminfo, S_IRUGO, node_read_meminfo, NULL);
158
159static ssize_t node_read_numastat(struct device *dev,
160				struct device_attribute *attr, char *buf)
161{
162	return sprintf(buf,
163		       "numa_hit %lu\n"
164		       "numa_miss %lu\n"
165		       "numa_foreign %lu\n"
166		       "interleave_hit %lu\n"
167		       "local_node %lu\n"
168		       "other_node %lu\n",
169		       node_page_state(dev->id, NUMA_HIT),
170		       node_page_state(dev->id, NUMA_MISS),
171		       node_page_state(dev->id, NUMA_FOREIGN),
172		       node_page_state(dev->id, NUMA_INTERLEAVE_HIT),
173		       node_page_state(dev->id, NUMA_LOCAL),
174		       node_page_state(dev->id, NUMA_OTHER));
 
175}
176static DEVICE_ATTR(numastat, S_IRUGO, node_read_numastat, NULL);
177
178static ssize_t node_read_vmstat(struct device *dev,
179				struct device_attribute *attr, char *buf)
180{
181	int nid = dev->id;
 
182	int i;
183	int n = 0;
184
185	for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
186		n += sprintf(buf+n, "%s %lu\n", vmstat_text[i],
187			     node_page_state(nid, 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
214#ifdef CONFIG_HUGETLBFS
215/*
216 * hugetlbfs per node attributes registration interface:
217 * When/if hugetlb[fs] subsystem initializes [sometime after this module],
218 * it will register its per node attributes for all online nodes with
219 * memory.  It will also call register_hugetlbfs_with_node(), below, to
220 * register its attribute registration functions with this node driver.
221 * Once these hooks have been initialized, the node driver will call into
222 * the hugetlb module to [un]register attributes for hot-plugged nodes.
223 */
224static node_registration_func_t __hugetlb_register_node;
225static node_registration_func_t __hugetlb_unregister_node;
 
226
227static inline bool hugetlb_register_node(struct node *node)
228{
229	if (__hugetlb_register_node &&
230			node_state(node->dev.id, N_HIGH_MEMORY)) {
231		__hugetlb_register_node(node);
232		return true;
233	}
234	return false;
235}
236
237static inline void hugetlb_unregister_node(struct node *node)
238{
239	if (__hugetlb_unregister_node)
240		__hugetlb_unregister_node(node);
241}
 
 
 
 
 
242
243void register_hugetlbfs_with_node(node_registration_func_t doregister,
244				  node_registration_func_t unregister)
245{
246	__hugetlb_register_node   = doregister;
247	__hugetlb_unregister_node = unregister;
248}
249#else
250static inline void hugetlb_register_node(struct node *node) {}
251
252static inline void hugetlb_unregister_node(struct node *node) {}
253#endif
254
255
256/*
257 * register_node - Setup a sysfs device for a node.
258 * @num - Node number to use when creating the device.
259 *
260 * Initialize and register the node device.
261 */
262int register_node(struct node *node, int num, struct node *parent)
263{
264	int error;
265
266	node->dev.id = num;
267	node->dev.bus = &node_subsys;
 
 
268	error = device_register(&node->dev);
269
270	if (!error){
271		device_create_file(&node->dev, &dev_attr_cpumap);
272		device_create_file(&node->dev, &dev_attr_cpulist);
273		device_create_file(&node->dev, &dev_attr_meminfo);
274		device_create_file(&node->dev, &dev_attr_numastat);
275		device_create_file(&node->dev, &dev_attr_distance);
276		device_create_file(&node->dev, &dev_attr_vmstat);
277
278		scan_unevictable_register_node(node);
279
280		hugetlb_register_node(node);
281
282		compaction_register_node(node);
283	}
 
284	return error;
285}
286
287/**
288 * unregister_node - unregister a node device
289 * @node: node going away
290 *
291 * Unregisters a node device @node.  All the devices on the node must be
292 * unregistered before calling this function.
293 */
294void unregister_node(struct node *node)
295{
296	device_remove_file(&node->dev, &dev_attr_cpumap);
297	device_remove_file(&node->dev, &dev_attr_cpulist);
298	device_remove_file(&node->dev, &dev_attr_meminfo);
299	device_remove_file(&node->dev, &dev_attr_numastat);
300	device_remove_file(&node->dev, &dev_attr_distance);
301	device_remove_file(&node->dev, &dev_attr_vmstat);
302
303	scan_unevictable_unregister_node(node);
304	hugetlb_unregister_node(node);		/* no-op, if memoryless node */
305
306	device_unregister(&node->dev);
307}
308
309struct node node_devices[MAX_NUMNODES];
310
311/*
312 * register cpu under node
313 */
314int register_cpu_under_node(unsigned int cpu, unsigned int nid)
315{
316	int ret;
317	struct device *obj;
318
319	if (!node_online(nid))
320		return 0;
321
322	obj = get_cpu_device(cpu);
323	if (!obj)
324		return 0;
325
326	ret = sysfs_create_link(&node_devices[nid].dev.kobj,
327				&obj->kobj,
328				kobject_name(&obj->kobj));
329	if (ret)
330		return ret;
331
332	return sysfs_create_link(&obj->kobj,
333				 &node_devices[nid].dev.kobj,
334				 kobject_name(&node_devices[nid].dev.kobj));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
335}
336
337int unregister_cpu_under_node(unsigned int cpu, unsigned int nid)
338{
339	struct device *obj;
340
341	if (!node_online(nid))
342		return 0;
343
344	obj = get_cpu_device(cpu);
345	if (!obj)
346		return 0;
347
348	sysfs_remove_link(&node_devices[nid].dev.kobj,
349			  kobject_name(&obj->kobj));
350	sysfs_remove_link(&obj->kobj,
351			  kobject_name(&node_devices[nid].dev.kobj));
352
353	return 0;
354}
355
356#ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
357#define page_initialized(page)  (page->lru.next)
 
 
 
 
 
 
 
358
359static int get_nid_for_pfn(unsigned long pfn)
 
 
360{
361	struct page *page;
 
 
362
363	if (!pfn_valid_within(pfn))
364		return -1;
365	page = pfn_to_page(pfn);
366	if (!page_initialized(page))
367		return -1;
368	return pfn_to_nid(pfn);
 
 
 
 
 
 
 
 
 
 
369}
370
371/* register memory section under specified node if it spans that node */
372int register_mem_sect_under_node(struct memory_block *mem_blk, int nid)
 
373{
374	int ret;
375	unsigned long pfn, sect_start_pfn, sect_end_pfn;
 
 
 
376
377	if (!mem_blk)
378		return -EFAULT;
379	if (!node_online(nid))
380		return 0;
381
382	sect_start_pfn = section_nr_to_pfn(mem_blk->start_section_nr);
383	sect_end_pfn = section_nr_to_pfn(mem_blk->end_section_nr);
384	sect_end_pfn += PAGES_PER_SECTION - 1;
385	for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) {
386		int page_nid;
 
 
 
 
387
 
 
 
 
388		page_nid = get_nid_for_pfn(pfn);
389		if (page_nid < 0)
390			continue;
391		if (page_nid != nid)
392			continue;
393		ret = sysfs_create_link_nowarn(&node_devices[nid].dev.kobj,
394					&mem_blk->dev.kobj,
395					kobject_name(&mem_blk->dev.kobj));
396		if (ret)
397			return ret;
398
399		return sysfs_create_link_nowarn(&mem_blk->dev.kobj,
400				&node_devices[nid].dev.kobj,
401				kobject_name(&node_devices[nid].dev.kobj));
402	}
403	/* mem section does not span the specified node */
404	return 0;
405}
406
407/* unregister memory section under all nodes that it spans */
408int unregister_mem_sect_under_nodes(struct memory_block *mem_blk,
409				    unsigned long phys_index)
410{
411	NODEMASK_ALLOC(nodemask_t, unlinked_nodes, GFP_KERNEL);
412	unsigned long pfn, sect_start_pfn, sect_end_pfn;
413
414	if (!mem_blk) {
415		NODEMASK_FREE(unlinked_nodes);
416		return -EFAULT;
417	}
418	if (!unlinked_nodes)
419		return -ENOMEM;
420	nodes_clear(*unlinked_nodes);
421
422	sect_start_pfn = section_nr_to_pfn(phys_index);
423	sect_end_pfn = sect_start_pfn + PAGES_PER_SECTION - 1;
424	for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) {
425		int nid;
426
427		nid = get_nid_for_pfn(pfn);
428		if (nid < 0)
429			continue;
430		if (!node_online(nid))
431			continue;
432		if (node_test_and_set(nid, *unlinked_nodes))
433			continue;
434		sysfs_remove_link(&node_devices[nid].dev.kobj,
435			 kobject_name(&mem_blk->dev.kobj));
436		sysfs_remove_link(&mem_blk->dev.kobj,
437			 kobject_name(&node_devices[nid].dev.kobj));
438	}
439	NODEMASK_FREE(unlinked_nodes);
440	return 0;
441}
442
443static int link_mem_sections(int nid)
444{
445	unsigned long start_pfn = NODE_DATA(nid)->node_start_pfn;
446	unsigned long end_pfn = start_pfn + NODE_DATA(nid)->node_spanned_pages;
447	unsigned long pfn;
448	struct memory_block *mem_blk = NULL;
449	int err = 0;
450
451	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
452		unsigned long section_nr = pfn_to_section_nr(pfn);
453		struct mem_section *mem_sect;
454		int ret;
455
456		if (!present_section_nr(section_nr))
457			continue;
458		mem_sect = __nr_to_section(section_nr);
459
460		/* same memblock ? */
461		if (mem_blk)
462			if ((section_nr >= mem_blk->start_section_nr) &&
463			    (section_nr <= mem_blk->end_section_nr))
464				continue;
465
466		mem_blk = find_memory_block_hinted(mem_sect, mem_blk);
467
468		ret = register_mem_sect_under_node(mem_blk, nid);
469		if (!err)
470			err = ret;
471
472		/* discard ref obtained in find_memory_block() */
473	}
474
475	if (mem_blk)
476		kobject_put(&mem_blk->dev.kobj);
477	return err;
478}
479
480#ifdef CONFIG_HUGETLBFS
481/*
482 * Handle per node hstate attribute [un]registration on transistions
483 * to/from memoryless state.
484 */
485static void node_hugetlb_work(struct work_struct *work)
486{
487	struct node *node = container_of(work, struct node, node_work);
 
488
489	/*
490	 * We only get here when a node transitions to/from memoryless state.
491	 * We can detect which transition occurred by examining whether the
492	 * node has memory now.  hugetlb_register_node() already check this
493	 * so we try to register the attributes.  If that fails, then the
494	 * node has transitioned to memoryless, try to unregister the
495	 * attributes.
496	 */
497	if (!hugetlb_register_node(node))
498		hugetlb_unregister_node(node);
499}
500
501static void init_node_hugetlb_work(int nid)
 
 
502{
503	INIT_WORK(&node_devices[nid].node_work, node_hugetlb_work);
504}
505
506static int node_memory_callback(struct notifier_block *self,
507				unsigned long action, void *arg)
508{
509	struct memory_notify *mnb = arg;
510	int nid = mnb->status_change_nid;
511
512	switch (action) {
513	case MEM_ONLINE:
514	case MEM_OFFLINE:
515		/*
516		 * offload per node hstate [un]registration to a work thread
517		 * when transitioning to/from memoryless state.
518		 */
519		if (nid != NUMA_NO_NODE)
520			schedule_work(&node_devices[nid].node_work);
521		break;
522
523	case MEM_GOING_ONLINE:
524	case MEM_GOING_OFFLINE:
525	case MEM_CANCEL_ONLINE:
526	case MEM_CANCEL_OFFLINE:
527	default:
528		break;
529	}
530
531	return NOTIFY_OK;
 
 
532}
533#endif	/* CONFIG_HUGETLBFS */
534#else	/* !CONFIG_MEMORY_HOTPLUG_SPARSE */
535
536static int link_mem_sections(int nid) { return 0; }
537#endif	/* CONFIG_MEMORY_HOTPLUG_SPARSE */
538
539#if !defined(CONFIG_MEMORY_HOTPLUG_SPARSE) || \
540    !defined(CONFIG_HUGETLBFS)
541static inline int node_memory_callback(struct notifier_block *self,
542				unsigned long action, void *arg)
543{
544	return NOTIFY_OK;
545}
 
546
547static void init_node_hugetlb_work(int nid) { }
 
 
548
549#endif
 
550
551int register_one_node(int nid)
552{
553	int error = 0;
554	int cpu;
555
556	if (node_online(nid)) {
557		int p_node = parent_node(nid);
558		struct node *parent = NULL;
559
560		if (p_node != nid)
561			parent = &node_devices[p_node];
562
563		error = register_node(&node_devices[nid], nid, parent);
564
565		/* link cpu under this node */
566		for_each_present_cpu(cpu) {
567			if (cpu_to_node(cpu) == nid)
568				register_cpu_under_node(cpu, nid);
569		}
570
571		/* link memory sections under this node */
572		error = link_mem_sections(nid);
573
574		/* initialize work queue for memory hot plug */
575		init_node_hugetlb_work(nid);
576	}
577
578	return error;
579
580}
581
582void unregister_one_node(int nid)
583{
584	unregister_node(&node_devices[nid]);
 
 
 
 
585}
586
587/*
588 * node states attributes
589 */
590
591static ssize_t print_nodes_state(enum node_states state, char *buf)
592{
593	int n;
594
595	n = nodelist_scnprintf(buf, PAGE_SIZE-2, node_states[state]);
596	buf[n++] = '\n';
597	buf[n] = '\0';
598	return n;
599}
600
601struct node_attr {
602	struct device_attribute attr;
603	enum node_states state;
604};
605
606static ssize_t show_node_state(struct device *dev,
607			       struct device_attribute *attr, char *buf)
608{
609	struct node_attr *na = container_of(attr, struct node_attr, attr);
610	return print_nodes_state(na->state, buf);
 
 
611}
612
613#define _NODE_ATTR(name, state) \
614	{ __ATTR(name, 0444, show_node_state, NULL), state }
615
616static struct node_attr node_state_attr[] = {
617	_NODE_ATTR(possible, N_POSSIBLE),
618	_NODE_ATTR(online, N_ONLINE),
619	_NODE_ATTR(has_normal_memory, N_NORMAL_MEMORY),
620	_NODE_ATTR(has_cpu, N_CPU),
621#ifdef CONFIG_HIGHMEM
622	_NODE_ATTR(has_high_memory, N_HIGH_MEMORY),
623#endif
 
 
 
 
624};
625
626static struct attribute *node_state_attrs[] = {
627	&node_state_attr[0].attr.attr,
628	&node_state_attr[1].attr.attr,
629	&node_state_attr[2].attr.attr,
630	&node_state_attr[3].attr.attr,
631#ifdef CONFIG_HIGHMEM
632	&node_state_attr[4].attr.attr,
633#endif
 
 
 
634	NULL
635};
636
637static struct attribute_group memory_root_attr_group = {
638	.attrs = node_state_attrs,
639};
640
641static const struct attribute_group *cpu_root_attr_groups[] = {
642	&memory_root_attr_group,
643	NULL,
644};
645
646#define NODE_CALLBACK_PRI	2	/* lower than SLAB */
647static int __init register_node_type(void)
648{
649	int ret;
650
651 	BUILD_BUG_ON(ARRAY_SIZE(node_state_attr) != NR_NODE_STATES);
652 	BUILD_BUG_ON(ARRAY_SIZE(node_state_attrs)-1 != NR_NODE_STATES);
653
654	ret = subsys_system_register(&node_subsys, cpu_root_attr_groups);
655	if (!ret) {
656		hotplug_memory_notifier(node_memory_callback,
657					NODE_CALLBACK_PRI);
658	}
659
660	/*
661	 * Note:  we're not going to unregister the node class if we fail
662	 * to register the node state class attribute files.
663	 */
664	return ret;
 
 
 
 
665}
666postcore_initcall(register_node_type);