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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}
v4.6
 
  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/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 sysinfo i;
 
 
 60
 61	si_meminfo_node(&i, nid);
 62	n = sprintf(buf,
 63		       "Node %d MemTotal:       %8lu kB\n"
 64		       "Node %d MemFree:        %8lu kB\n"
 65		       "Node %d MemUsed:        %8lu kB\n"
 66		       "Node %d Active:         %8lu kB\n"
 67		       "Node %d Inactive:       %8lu kB\n"
 68		       "Node %d Active(anon):   %8lu kB\n"
 69		       "Node %d Inactive(anon): %8lu kB\n"
 70		       "Node %d Active(file):   %8lu kB\n"
 71		       "Node %d Inactive(file): %8lu kB\n"
 72		       "Node %d Unevictable:    %8lu kB\n"
 73		       "Node %d Mlocked:        %8lu kB\n",
 74		       nid, K(i.totalram),
 75		       nid, K(i.freeram),
 76		       nid, K(i.totalram - i.freeram),
 77		       nid, K(node_page_state(nid, NR_ACTIVE_ANON) +
 78				node_page_state(nid, NR_ACTIVE_FILE)),
 79		       nid, K(node_page_state(nid, NR_INACTIVE_ANON) +
 80				node_page_state(nid, NR_INACTIVE_FILE)),
 81		       nid, K(node_page_state(nid, NR_ACTIVE_ANON)),
 82		       nid, K(node_page_state(nid, NR_INACTIVE_ANON)),
 83		       nid, K(node_page_state(nid, NR_ACTIVE_FILE)),
 84		       nid, K(node_page_state(nid, NR_INACTIVE_FILE)),
 85		       nid, K(node_page_state(nid, NR_UNEVICTABLE)),
 86		       nid, K(node_page_state(nid, NR_MLOCK)));
 
 
 
 
 
 
 
 87
 88#ifdef CONFIG_HIGHMEM
 89	n += sprintf(buf + n,
 90		       "Node %d HighTotal:      %8lu kB\n"
 91		       "Node %d HighFree:       %8lu kB\n"
 92		       "Node %d LowTotal:       %8lu kB\n"
 93		       "Node %d LowFree:        %8lu kB\n",
 94		       nid, K(i.totalhigh),
 95		       nid, K(i.freehigh),
 96		       nid, K(i.totalram - i.totalhigh),
 97		       nid, K(i.freeram - i.freehigh));
 98#endif
 99	n += sprintf(buf + n,
100		       "Node %d Dirty:          %8lu kB\n"
101		       "Node %d Writeback:      %8lu kB\n"
102		       "Node %d FilePages:      %8lu kB\n"
103		       "Node %d Mapped:         %8lu kB\n"
104		       "Node %d AnonPages:      %8lu kB\n"
105		       "Node %d Shmem:          %8lu kB\n"
106		       "Node %d KernelStack:    %8lu kB\n"
107		       "Node %d PageTables:     %8lu kB\n"
108		       "Node %d NFS_Unstable:   %8lu kB\n"
109		       "Node %d Bounce:         %8lu kB\n"
110		       "Node %d WritebackTmp:   %8lu kB\n"
111		       "Node %d Slab:           %8lu kB\n"
112		       "Node %d SReclaimable:   %8lu kB\n"
113		       "Node %d SUnreclaim:     %8lu kB\n"
 
 
 
 
 
114#ifdef CONFIG_TRANSPARENT_HUGEPAGE
115		       "Node %d AnonHugePages:  %8lu kB\n"
116#endif
117			,
118		       nid, K(node_page_state(nid, NR_FILE_DIRTY)),
119		       nid, K(node_page_state(nid, NR_WRITEBACK)),
120		       nid, K(node_page_state(nid, NR_FILE_PAGES)),
121		       nid, K(node_page_state(nid, NR_FILE_MAPPED)),
122		       nid, K(node_page_state(nid, NR_ANON_PAGES)),
123		       nid, K(i.sharedram),
124		       nid, node_page_state(nid, NR_KERNEL_STACK) *
125				THREAD_SIZE / 1024,
126		       nid, K(node_page_state(nid, NR_PAGETABLE)),
127		       nid, K(node_page_state(nid, NR_UNSTABLE_NFS)),
128		       nid, K(node_page_state(nid, NR_BOUNCE)),
129		       nid, K(node_page_state(nid, NR_WRITEBACK_TEMP)),
130		       nid, K(node_page_state(nid, NR_SLAB_RECLAIMABLE) +
131				node_page_state(nid, NR_SLAB_UNRECLAIMABLE)),
132		       nid, K(node_page_state(nid, NR_SLAB_RECLAIMABLE)),
 
 
 
 
 
 
 
 
 
 
 
 
133#ifdef CONFIG_TRANSPARENT_HUGEPAGE
134		       nid, K(node_page_state(nid, NR_SLAB_UNRECLAIMABLE))
135			, nid,
136			K(node_page_state(nid, NR_ANON_TRANSPARENT_HUGEPAGES) *
137			HPAGE_PMD_NR));
138#else
139		       nid, K(node_page_state(nid, NR_SLAB_UNRECLAIMABLE)));
 
 
 
 
140#endif
141	n += hugetlb_report_node_meminfo(nid, buf + n);
142	return n;
 
143}
144
145#undef K
146static DEVICE_ATTR(meminfo, S_IRUGO, node_read_meminfo, NULL);
147
148static ssize_t node_read_numastat(struct device *dev,
149				struct device_attribute *attr, char *buf)
150{
151	return sprintf(buf,
152		       "numa_hit %lu\n"
153		       "numa_miss %lu\n"
154		       "numa_foreign %lu\n"
155		       "interleave_hit %lu\n"
156		       "local_node %lu\n"
157		       "other_node %lu\n",
158		       node_page_state(dev->id, NUMA_HIT),
159		       node_page_state(dev->id, NUMA_MISS),
160		       node_page_state(dev->id, NUMA_FOREIGN),
161		       node_page_state(dev->id, NUMA_INTERLEAVE_HIT),
162		       node_page_state(dev->id, NUMA_LOCAL),
163		       node_page_state(dev->id, NUMA_OTHER));
 
164}
165static DEVICE_ATTR(numastat, S_IRUGO, node_read_numastat, NULL);
166
167static ssize_t node_read_vmstat(struct device *dev,
168				struct device_attribute *attr, char *buf)
169{
170	int nid = dev->id;
 
171	int i;
172	int n = 0;
173
174	for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
175		n += sprintf(buf+n, "%s %lu\n", vmstat_text[i],
176			     node_page_state(nid, i));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
177
178	return n;
179}
180static DEVICE_ATTR(vmstat, S_IRUGO, node_read_vmstat, NULL);
181
182static ssize_t node_read_distance(struct device *dev,
183			struct device_attribute *attr, char *buf)
184{
185	int nid = dev->id;
186	int len = 0;
187	int i;
188
189	/*
190	 * buf is currently PAGE_SIZE in length and each node needs 4 chars
191	 * at the most (distance + space or newline).
192	 */
193	BUILD_BUG_ON(MAX_NUMNODES * 4 > PAGE_SIZE);
194
195	for_each_online_node(i)
196		len += sprintf(buf + len, "%s%d", i ? " " : "", node_distance(nid, i));
 
 
197
198	len += sprintf(buf + len, "\n");
199	return len;
200}
201static DEVICE_ATTR(distance, S_IRUGO, node_read_distance, NULL);
202
203static struct attribute *node_dev_attrs[] = {
204	&dev_attr_cpumap.attr,
205	&dev_attr_cpulist.attr,
206	&dev_attr_meminfo.attr,
207	&dev_attr_numastat.attr,
208	&dev_attr_distance.attr,
209	&dev_attr_vmstat.attr,
210	NULL
211};
212ATTRIBUTE_GROUPS(node_dev);
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_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
255static void node_device_release(struct device *dev)
256{
257	struct node *node = to_node(dev);
258
259#if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HUGETLBFS)
260	/*
261	 * We schedule the work only when a memory section is
262	 * onlined/offlined on this node. When we come here,
263	 * all the memory on this node has been offlined,
264	 * so we won't enqueue new work to this work.
265	 *
266	 * The work is using node->node_work, so we should
267	 * flush work before freeing the memory.
268	 */
269	flush_work(&node->node_work);
270#endif
271	kfree(node);
272}
273
274/*
275 * register_node - Setup a sysfs device for a node.
276 * @num - Node number to use when creating the device.
277 *
278 * Initialize and register the node device.
279 */
280static int register_node(struct node *node, int num, struct node *parent)
281{
282	int error;
283
284	node->dev.id = num;
285	node->dev.bus = &node_subsys;
286	node->dev.release = node_device_release;
287	node->dev.groups = node_dev_groups;
288	error = device_register(&node->dev);
289
290	if (!error){
 
 
291		hugetlb_register_node(node);
292
293		compaction_register_node(node);
294	}
 
295	return error;
296}
297
298/**
299 * unregister_node - unregister a node device
300 * @node: node going away
301 *
302 * Unregisters a node device @node.  All the devices on the node must be
303 * unregistered before calling this function.
304 */
305void unregister_node(struct node *node)
306{
307	hugetlb_unregister_node(node);		/* no-op, if memoryless node */
308
 
 
309	device_unregister(&node->dev);
310}
311
312struct node *node_devices[MAX_NUMNODES];
313
314/*
315 * register cpu under node
316 */
317int register_cpu_under_node(unsigned int cpu, unsigned int nid)
318{
319	int ret;
320	struct device *obj;
321
322	if (!node_online(nid))
323		return 0;
324
325	obj = get_cpu_device(cpu);
326	if (!obj)
327		return 0;
328
329	ret = sysfs_create_link(&node_devices[nid]->dev.kobj,
330				&obj->kobj,
331				kobject_name(&obj->kobj));
332	if (ret)
333		return ret;
334
335	return sysfs_create_link(&obj->kobj,
336				 &node_devices[nid]->dev.kobj,
337				 kobject_name(&node_devices[nid]->dev.kobj));
338}
339
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
340int unregister_cpu_under_node(unsigned int cpu, unsigned int nid)
341{
342	struct device *obj;
343
344	if (!node_online(nid))
345		return 0;
346
347	obj = get_cpu_device(cpu);
348	if (!obj)
349		return 0;
350
351	sysfs_remove_link(&node_devices[nid]->dev.kobj,
352			  kobject_name(&obj->kobj));
353	sysfs_remove_link(&obj->kobj,
354			  kobject_name(&node_devices[nid]->dev.kobj));
355
356	return 0;
357}
358
359#ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
360#define page_initialized(page)  (page->lru.next)
361
362static int __init_refok get_nid_for_pfn(unsigned long pfn)
363{
364	struct page *page;
365
366	if (!pfn_valid_within(pfn))
367		return -1;
368#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
369	if (system_state == SYSTEM_BOOTING)
370		return early_pfn_to_nid(pfn);
371#endif
372	page = pfn_to_page(pfn);
373	if (!page_initialized(page))
374		return -1;
375	return pfn_to_nid(pfn);
376}
377
378/* register memory section under specified node if it spans that node */
379int register_mem_sect_under_node(struct memory_block *mem_blk, int nid)
 
380{
381	int ret;
382	unsigned long pfn, sect_start_pfn, sect_end_pfn;
383
384	if (!mem_blk)
385		return -EFAULT;
386	if (!node_online(nid))
387		return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
388
389	sect_start_pfn = section_nr_to_pfn(mem_blk->start_section_nr);
390	sect_end_pfn = section_nr_to_pfn(mem_blk->end_section_nr);
391	sect_end_pfn += PAGES_PER_SECTION - 1;
392	for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) {
393		int page_nid;
394
395		/*
396		 * memory block could have several absent sections from start.
397		 * skip pfn range from absent section
398		 */
399		if (!pfn_present(pfn)) {
400			pfn = round_down(pfn + PAGES_PER_SECTION,
401					 PAGES_PER_SECTION) - 1;
402			continue;
403		}
404
 
 
 
 
405		page_nid = get_nid_for_pfn(pfn);
406		if (page_nid < 0)
407			continue;
408		if (page_nid != nid)
409			continue;
410		ret = sysfs_create_link_nowarn(&node_devices[nid]->dev.kobj,
411					&mem_blk->dev.kobj,
412					kobject_name(&mem_blk->dev.kobj));
413		if (ret)
414			return ret;
415
416		return sysfs_create_link_nowarn(&mem_blk->dev.kobj,
417				&node_devices[nid]->dev.kobj,
418				kobject_name(&node_devices[nid]->dev.kobj));
419	}
420	/* mem section does not span the specified node */
421	return 0;
422}
423
424/* unregister memory section under all nodes that it spans */
425int unregister_mem_sect_under_nodes(struct memory_block *mem_blk,
426				    unsigned long phys_index)
427{
428	NODEMASK_ALLOC(nodemask_t, unlinked_nodes, GFP_KERNEL);
429	unsigned long pfn, sect_start_pfn, sect_end_pfn;
430
431	if (!mem_blk) {
432		NODEMASK_FREE(unlinked_nodes);
433		return -EFAULT;
434	}
435	if (!unlinked_nodes)
436		return -ENOMEM;
437	nodes_clear(*unlinked_nodes);
438
439	sect_start_pfn = section_nr_to_pfn(phys_index);
440	sect_end_pfn = sect_start_pfn + PAGES_PER_SECTION - 1;
441	for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) {
442		int nid;
443
444		nid = get_nid_for_pfn(pfn);
445		if (nid < 0)
446			continue;
447		if (!node_online(nid))
448			continue;
449		if (node_test_and_set(nid, *unlinked_nodes))
450			continue;
451		sysfs_remove_link(&node_devices[nid]->dev.kobj,
452			 kobject_name(&mem_blk->dev.kobj));
453		sysfs_remove_link(&mem_blk->dev.kobj,
454			 kobject_name(&node_devices[nid]->dev.kobj));
455	}
456	NODEMASK_FREE(unlinked_nodes);
457	return 0;
458}
459
460static int link_mem_sections(int nid)
461{
462	unsigned long start_pfn = NODE_DATA(nid)->node_start_pfn;
463	unsigned long end_pfn = start_pfn + NODE_DATA(nid)->node_spanned_pages;
464	unsigned long pfn;
465	struct memory_block *mem_blk = NULL;
466	int err = 0;
467
468	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
469		unsigned long section_nr = pfn_to_section_nr(pfn);
470		struct mem_section *mem_sect;
471		int ret;
472
473		if (!present_section_nr(section_nr))
474			continue;
475		mem_sect = __nr_to_section(section_nr);
476
477		/* same memblock ? */
478		if (mem_blk)
479			if ((section_nr >= mem_blk->start_section_nr) &&
480			    (section_nr <= mem_blk->end_section_nr))
481				continue;
482
483		mem_blk = find_memory_block_hinted(mem_sect, mem_blk);
484
485		ret = register_mem_sect_under_node(mem_blk, nid);
486		if (!err)
487			err = ret;
488
489		/* discard ref obtained in find_memory_block() */
490	}
491
492	if (mem_blk)
493		kobject_put(&mem_blk->dev.kobj);
494	return err;
495}
496
497#ifdef CONFIG_HUGETLBFS
498/*
499 * Handle per node hstate attribute [un]registration on transistions
500 * to/from memoryless state.
501 */
502static void node_hugetlb_work(struct work_struct *work)
503{
504	struct node *node = container_of(work, struct node, node_work);
 
505
506	/*
507	 * We only get here when a node transitions to/from memoryless state.
508	 * We can detect which transition occurred by examining whether the
509	 * node has memory now.  hugetlb_register_node() already check this
510	 * so we try to register the attributes.  If that fails, then the
511	 * node has transitioned to memoryless, try to unregister the
512	 * attributes.
513	 */
514	if (!hugetlb_register_node(node))
515		hugetlb_unregister_node(node);
516}
517
518static void init_node_hugetlb_work(int nid)
 
 
519{
520	INIT_WORK(&node_devices[nid]->node_work, node_hugetlb_work);
521}
522
523static int node_memory_callback(struct notifier_block *self,
524				unsigned long action, void *arg)
525{
526	struct memory_notify *mnb = arg;
527	int nid = mnb->status_change_nid;
528
529	switch (action) {
530	case MEM_ONLINE:
531	case MEM_OFFLINE:
532		/*
533		 * offload per node hstate [un]registration to a work thread
534		 * when transitioning to/from memoryless state.
535		 */
536		if (nid != NUMA_NO_NODE)
537			schedule_work(&node_devices[nid]->node_work);
538		break;
539
540	case MEM_GOING_ONLINE:
541	case MEM_GOING_OFFLINE:
542	case MEM_CANCEL_ONLINE:
543	case MEM_CANCEL_OFFLINE:
544	default:
545		break;
546	}
547
548	return NOTIFY_OK;
 
 
549}
550#endif	/* CONFIG_HUGETLBFS */
551#else	/* !CONFIG_MEMORY_HOTPLUG_SPARSE */
552
553static int link_mem_sections(int nid) { return 0; }
554#endif	/* CONFIG_MEMORY_HOTPLUG_SPARSE */
555
556#if !defined(CONFIG_MEMORY_HOTPLUG_SPARSE) || \
557    !defined(CONFIG_HUGETLBFS)
558static inline int node_memory_callback(struct notifier_block *self,
559				unsigned long action, void *arg)
560{
561	return NOTIFY_OK;
562}
 
563
564static void init_node_hugetlb_work(int nid) { }
 
 
565
566#endif
 
567
568int register_one_node(int nid)
569{
570	int error = 0;
571	int cpu;
572
573	if (node_online(nid)) {
574		int p_node = parent_node(nid);
575		struct node *parent = NULL;
576
577		if (p_node != nid)
578			parent = node_devices[p_node];
579
580		node_devices[nid] = kzalloc(sizeof(struct node), GFP_KERNEL);
581		if (!node_devices[nid])
582			return -ENOMEM;
583
584		error = register_node(node_devices[nid], nid, parent);
585
586		/* link cpu under this node */
587		for_each_present_cpu(cpu) {
588			if (cpu_to_node(cpu) == nid)
589				register_cpu_under_node(cpu, nid);
590		}
591
592		/* link memory sections under this node */
593		error = link_mem_sections(nid);
594
595		/* initialize work queue for memory hot plug */
596		init_node_hugetlb_work(nid);
597	}
598
599	return error;
600
601}
602
603void unregister_one_node(int nid)
604{
605	if (!node_devices[nid])
606		return;
607
608	unregister_node(node_devices[nid]);
609	node_devices[nid] = NULL;
610}
611
612/*
613 * node states attributes
614 */
615
616static ssize_t print_nodes_state(enum node_states state, char *buf)
617{
618	int n;
619
620	n = scnprintf(buf, PAGE_SIZE - 1, "%*pbl",
621		      nodemask_pr_args(&node_states[state]));
622	buf[n++] = '\n';
623	buf[n] = '\0';
624	return n;
625}
626
627struct node_attr {
628	struct device_attribute attr;
629	enum node_states state;
630};
631
632static ssize_t show_node_state(struct device *dev,
633			       struct device_attribute *attr, char *buf)
634{
635	struct node_attr *na = container_of(attr, struct node_attr, attr);
636	return print_nodes_state(na->state, buf);
 
 
637}
638
639#define _NODE_ATTR(name, state) \
640	{ __ATTR(name, 0444, show_node_state, NULL), state }
641
642static struct node_attr node_state_attr[] = {
643	[N_POSSIBLE] = _NODE_ATTR(possible, N_POSSIBLE),
644	[N_ONLINE] = _NODE_ATTR(online, N_ONLINE),
645	[N_NORMAL_MEMORY] = _NODE_ATTR(has_normal_memory, N_NORMAL_MEMORY),
646#ifdef CONFIG_HIGHMEM
647	[N_HIGH_MEMORY] = _NODE_ATTR(has_high_memory, N_HIGH_MEMORY),
648#endif
649#ifdef CONFIG_MOVABLE_NODE
650	[N_MEMORY] = _NODE_ATTR(has_memory, N_MEMORY),
651#endif
652	[N_CPU] = _NODE_ATTR(has_cpu, N_CPU),
 
 
653};
654
655static struct attribute *node_state_attrs[] = {
656	&node_state_attr[N_POSSIBLE].attr.attr,
657	&node_state_attr[N_ONLINE].attr.attr,
658	&node_state_attr[N_NORMAL_MEMORY].attr.attr,
659#ifdef CONFIG_HIGHMEM
660	&node_state_attr[N_HIGH_MEMORY].attr.attr,
661#endif
662#ifdef CONFIG_MOVABLE_NODE
663	&node_state_attr[N_MEMORY].attr.attr,
664#endif
665	&node_state_attr[N_CPU].attr.attr,
 
666	NULL
667};
668
669static struct attribute_group memory_root_attr_group = {
670	.attrs = node_state_attrs,
671};
672
673static const struct attribute_group *cpu_root_attr_groups[] = {
674	&memory_root_attr_group,
675	NULL,
676};
677
678#define NODE_CALLBACK_PRI	2	/* lower than SLAB */
679static int __init register_node_type(void)
680{
681	int ret;
682
683 	BUILD_BUG_ON(ARRAY_SIZE(node_state_attr) != NR_NODE_STATES);
684 	BUILD_BUG_ON(ARRAY_SIZE(node_state_attrs)-1 != NR_NODE_STATES);
685
686	ret = subsys_system_register(&node_subsys, cpu_root_attr_groups);
687	if (!ret) {
688		static struct notifier_block node_memory_callback_nb = {
689			.notifier_call = node_memory_callback,
690			.priority = NODE_CALLBACK_PRI,
691		};
692		register_hotmemory_notifier(&node_memory_callback_nb);
693	}
694
695	/*
696	 * Note:  we're not going to unregister the node class if we fail
697	 * to register the node state class attribute files.
698	 */
699	return ret;
 
 
 
 
700}
701postcore_initcall(register_node_type);