2 * Basic Node interface support
5 #include <linux/module.h>
6 #include <linux/init.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>
22 static struct bus_type node_subsys = {
28 static ssize_t node_read_cpumap(struct device *dev, bool list, char *buf)
30 struct node *node_dev = to_node(dev);
31 const struct cpumask *mask = cpumask_of_node(node_dev->dev.id);
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));
36 return cpumap_print_to_pagebuf(list, buf, mask);
39 static inline ssize_t node_read_cpumask(struct device *dev,
40 struct device_attribute *attr, char *buf)
42 return node_read_cpumap(dev, false, buf);
44 static inline ssize_t node_read_cpulist(struct device *dev,
45 struct device_attribute *attr, char *buf)
47 return node_read_cpumap(dev, true, buf);
50 static DEVICE_ATTR(cpumap, S_IRUGO, node_read_cpumask, NULL);
51 static DEVICE_ATTR(cpulist, S_IRUGO, node_read_cpulist, NULL);
53 #define K(x) ((x) << (PAGE_SHIFT - 10))
54 static ssize_t node_read_meminfo(struct device *dev,
55 struct device_attribute *attr, char *buf)
59 struct pglist_data *pgdat = NODE_DATA(nid);
62 si_meminfo_node(&i, nid);
64 "Node %d MemTotal: %8lu kB\n"
65 "Node %d MemFree: %8lu kB\n"
66 "Node %d MemUsed: %8lu kB\n"
67 "Node %d Active: %8lu kB\n"
68 "Node %d Inactive: %8lu kB\n"
69 "Node %d Active(anon): %8lu kB\n"
70 "Node %d Inactive(anon): %8lu kB\n"
71 "Node %d Active(file): %8lu kB\n"
72 "Node %d Inactive(file): %8lu kB\n"
73 "Node %d Unevictable: %8lu kB\n"
74 "Node %d Mlocked: %8lu kB\n",
77 nid, K(i.totalram - i.freeram),
78 nid, K(node_page_state(pgdat, NR_ACTIVE_ANON) +
79 node_page_state(pgdat, NR_ACTIVE_FILE)),
80 nid, K(node_page_state(pgdat, NR_INACTIVE_ANON) +
81 node_page_state(pgdat, NR_INACTIVE_FILE)),
82 nid, K(node_page_state(pgdat, NR_ACTIVE_ANON)),
83 nid, K(node_page_state(pgdat, NR_INACTIVE_ANON)),
84 nid, K(node_page_state(pgdat, NR_ACTIVE_FILE)),
85 nid, K(node_page_state(pgdat, NR_INACTIVE_FILE)),
86 nid, K(node_page_state(pgdat, NR_UNEVICTABLE)),
87 nid, K(sum_zone_node_page_state(nid, NR_MLOCK)));
91 "Node %d HighTotal: %8lu kB\n"
92 "Node %d HighFree: %8lu kB\n"
93 "Node %d LowTotal: %8lu kB\n"
94 "Node %d LowFree: %8lu kB\n",
97 nid, K(i.totalram - i.totalhigh),
98 nid, K(i.freeram - i.freehigh));
100 n += sprintf(buf + n,
101 "Node %d Dirty: %8lu kB\n"
102 "Node %d Writeback: %8lu kB\n"
103 "Node %d FilePages: %8lu kB\n"
104 "Node %d Mapped: %8lu kB\n"
105 "Node %d AnonPages: %8lu kB\n"
106 "Node %d Shmem: %8lu kB\n"
107 "Node %d KernelStack: %8lu kB\n"
108 "Node %d PageTables: %8lu kB\n"
109 "Node %d NFS_Unstable: %8lu kB\n"
110 "Node %d Bounce: %8lu kB\n"
111 "Node %d WritebackTmp: %8lu kB\n"
112 "Node %d Slab: %8lu kB\n"
113 "Node %d SReclaimable: %8lu kB\n"
114 "Node %d SUnreclaim: %8lu kB\n"
115 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
116 "Node %d AnonHugePages: %8lu kB\n"
117 "Node %d ShmemHugePages: %8lu kB\n"
118 "Node %d ShmemPmdMapped: %8lu kB\n"
121 nid, K(sum_zone_node_page_state(nid, NR_FILE_DIRTY)),
122 nid, K(sum_zone_node_page_state(nid, NR_WRITEBACK)),
123 nid, K(sum_zone_node_page_state(nid, NR_FILE_PAGES)),
124 nid, K(sum_zone_node_page_state(nid, NR_FILE_MAPPED)),
125 nid, K(sum_zone_node_page_state(nid, NR_ANON_PAGES)),
127 nid, sum_zone_node_page_state(nid, NR_KERNEL_STACK) *
129 nid, K(sum_zone_node_page_state(nid, NR_PAGETABLE)),
130 nid, K(sum_zone_node_page_state(nid, NR_UNSTABLE_NFS)),
131 nid, K(sum_zone_node_page_state(nid, NR_BOUNCE)),
132 nid, K(sum_zone_node_page_state(nid, NR_WRITEBACK_TEMP)),
133 nid, K(sum_zone_node_page_state(nid, NR_SLAB_RECLAIMABLE) +
134 sum_zone_node_page_state(nid, NR_SLAB_UNRECLAIMABLE)),
135 nid, K(sum_zone_node_page_state(nid, NR_SLAB_RECLAIMABLE)),
136 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
137 nid, K(sum_zone_node_page_state(nid, NR_SLAB_UNRECLAIMABLE)),
138 nid, K(sum_zone_node_page_state(nid, NR_ANON_THPS) *
140 nid, K(sum_zone_node_page_state(nid, NR_SHMEM_THPS) *
142 nid, K(sum_zone_node_page_state(nid, NR_SHMEM_PMDMAPPED) *
145 nid, K(sum_zone_node_page_state(nid, NR_SLAB_UNRECLAIMABLE)));
147 n += hugetlb_report_node_meminfo(nid, buf + n);
152 static DEVICE_ATTR(meminfo, S_IRUGO, node_read_meminfo, NULL);
154 static ssize_t node_read_numastat(struct device *dev,
155 struct device_attribute *attr, char *buf)
161 "interleave_hit %lu\n"
164 sum_zone_node_page_state(dev->id, NUMA_HIT),
165 sum_zone_node_page_state(dev->id, NUMA_MISS),
166 sum_zone_node_page_state(dev->id, NUMA_FOREIGN),
167 sum_zone_node_page_state(dev->id, NUMA_INTERLEAVE_HIT),
168 sum_zone_node_page_state(dev->id, NUMA_LOCAL),
169 sum_zone_node_page_state(dev->id, NUMA_OTHER));
171 static DEVICE_ATTR(numastat, S_IRUGO, node_read_numastat, NULL);
173 static ssize_t node_read_vmstat(struct device *dev,
174 struct device_attribute *attr, char *buf)
177 struct pglist_data *pgdat = NODE_DATA(nid);
181 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
182 n += sprintf(buf+n, "%s %lu\n", vmstat_text[i],
183 sum_zone_node_page_state(nid, i));
185 for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++)
186 n += sprintf(buf+n, "%s %lu\n",
187 vmstat_text[i + NR_VM_ZONE_STAT_ITEMS],
188 node_page_state(pgdat, i));
192 static DEVICE_ATTR(vmstat, S_IRUGO, node_read_vmstat, NULL);
194 static ssize_t node_read_distance(struct device *dev,
195 struct device_attribute *attr, char *buf)
202 * buf is currently PAGE_SIZE in length and each node needs 4 chars
203 * at the most (distance + space or newline).
205 BUILD_BUG_ON(MAX_NUMNODES * 4 > PAGE_SIZE);
207 for_each_online_node(i)
208 len += sprintf(buf + len, "%s%d", i ? " " : "", node_distance(nid, i));
210 len += sprintf(buf + len, "\n");
213 static DEVICE_ATTR(distance, S_IRUGO, node_read_distance, NULL);
215 static struct attribute *node_dev_attrs[] = {
216 &dev_attr_cpumap.attr,
217 &dev_attr_cpulist.attr,
218 &dev_attr_meminfo.attr,
219 &dev_attr_numastat.attr,
220 &dev_attr_distance.attr,
221 &dev_attr_vmstat.attr,
224 ATTRIBUTE_GROUPS(node_dev);
226 #ifdef CONFIG_HUGETLBFS
228 * hugetlbfs per node attributes registration interface:
229 * When/if hugetlb[fs] subsystem initializes [sometime after this module],
230 * it will register its per node attributes for all online nodes with
231 * memory. It will also call register_hugetlbfs_with_node(), below, to
232 * register its attribute registration functions with this node driver.
233 * Once these hooks have been initialized, the node driver will call into
234 * the hugetlb module to [un]register attributes for hot-plugged nodes.
236 static node_registration_func_t __hugetlb_register_node;
237 static node_registration_func_t __hugetlb_unregister_node;
239 static inline bool hugetlb_register_node(struct node *node)
241 if (__hugetlb_register_node &&
242 node_state(node->dev.id, N_MEMORY)) {
243 __hugetlb_register_node(node);
249 static inline void hugetlb_unregister_node(struct node *node)
251 if (__hugetlb_unregister_node)
252 __hugetlb_unregister_node(node);
255 void register_hugetlbfs_with_node(node_registration_func_t doregister,
256 node_registration_func_t unregister)
258 __hugetlb_register_node = doregister;
259 __hugetlb_unregister_node = unregister;
262 static inline void hugetlb_register_node(struct node *node) {}
264 static inline void hugetlb_unregister_node(struct node *node) {}
267 static void node_device_release(struct device *dev)
269 struct node *node = to_node(dev);
271 #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HUGETLBFS)
273 * We schedule the work only when a memory section is
274 * onlined/offlined on this node. When we come here,
275 * all the memory on this node has been offlined,
276 * so we won't enqueue new work to this work.
278 * The work is using node->node_work, so we should
279 * flush work before freeing the memory.
281 flush_work(&node->node_work);
287 * register_node - Setup a sysfs device for a node.
288 * @num - Node number to use when creating the device.
290 * Initialize and register the node device.
292 static int register_node(struct node *node, int num, struct node *parent)
297 node->dev.bus = &node_subsys;
298 node->dev.release = node_device_release;
299 node->dev.groups = node_dev_groups;
300 error = device_register(&node->dev);
303 hugetlb_register_node(node);
305 compaction_register_node(node);
311 * unregister_node - unregister a node device
312 * @node: node going away
314 * Unregisters a node device @node. All the devices on the node must be
315 * unregistered before calling this function.
317 void unregister_node(struct node *node)
319 hugetlb_unregister_node(node); /* no-op, if memoryless node */
321 device_unregister(&node->dev);
324 struct node *node_devices[MAX_NUMNODES];
327 * register cpu under node
329 int register_cpu_under_node(unsigned int cpu, unsigned int nid)
334 if (!node_online(nid))
337 obj = get_cpu_device(cpu);
341 ret = sysfs_create_link(&node_devices[nid]->dev.kobj,
343 kobject_name(&obj->kobj));
347 return sysfs_create_link(&obj->kobj,
348 &node_devices[nid]->dev.kobj,
349 kobject_name(&node_devices[nid]->dev.kobj));
352 int unregister_cpu_under_node(unsigned int cpu, unsigned int nid)
356 if (!node_online(nid))
359 obj = get_cpu_device(cpu);
363 sysfs_remove_link(&node_devices[nid]->dev.kobj,
364 kobject_name(&obj->kobj));
365 sysfs_remove_link(&obj->kobj,
366 kobject_name(&node_devices[nid]->dev.kobj));
371 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
372 #define page_initialized(page) (page->lru.next)
374 static int __init_refok get_nid_for_pfn(unsigned long pfn)
378 if (!pfn_valid_within(pfn))
380 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
381 if (system_state == SYSTEM_BOOTING)
382 return early_pfn_to_nid(pfn);
384 page = pfn_to_page(pfn);
385 if (!page_initialized(page))
387 return pfn_to_nid(pfn);
390 /* register memory section under specified node if it spans that node */
391 int register_mem_sect_under_node(struct memory_block *mem_blk, int nid)
394 unsigned long pfn, sect_start_pfn, sect_end_pfn;
398 if (!node_online(nid))
401 sect_start_pfn = section_nr_to_pfn(mem_blk->start_section_nr);
402 sect_end_pfn = section_nr_to_pfn(mem_blk->end_section_nr);
403 sect_end_pfn += PAGES_PER_SECTION - 1;
404 for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) {
408 * memory block could have several absent sections from start.
409 * skip pfn range from absent section
411 if (!pfn_present(pfn)) {
412 pfn = round_down(pfn + PAGES_PER_SECTION,
413 PAGES_PER_SECTION) - 1;
417 page_nid = get_nid_for_pfn(pfn);
422 ret = sysfs_create_link_nowarn(&node_devices[nid]->dev.kobj,
424 kobject_name(&mem_blk->dev.kobj));
428 return sysfs_create_link_nowarn(&mem_blk->dev.kobj,
429 &node_devices[nid]->dev.kobj,
430 kobject_name(&node_devices[nid]->dev.kobj));
432 /* mem section does not span the specified node */
436 /* unregister memory section under all nodes that it spans */
437 int unregister_mem_sect_under_nodes(struct memory_block *mem_blk,
438 unsigned long phys_index)
440 NODEMASK_ALLOC(nodemask_t, unlinked_nodes, GFP_KERNEL);
441 unsigned long pfn, sect_start_pfn, sect_end_pfn;
444 NODEMASK_FREE(unlinked_nodes);
449 nodes_clear(*unlinked_nodes);
451 sect_start_pfn = section_nr_to_pfn(phys_index);
452 sect_end_pfn = sect_start_pfn + PAGES_PER_SECTION - 1;
453 for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) {
456 nid = get_nid_for_pfn(pfn);
459 if (!node_online(nid))
461 if (node_test_and_set(nid, *unlinked_nodes))
463 sysfs_remove_link(&node_devices[nid]->dev.kobj,
464 kobject_name(&mem_blk->dev.kobj));
465 sysfs_remove_link(&mem_blk->dev.kobj,
466 kobject_name(&node_devices[nid]->dev.kobj));
468 NODEMASK_FREE(unlinked_nodes);
472 static int link_mem_sections(int nid)
474 unsigned long start_pfn = NODE_DATA(nid)->node_start_pfn;
475 unsigned long end_pfn = start_pfn + NODE_DATA(nid)->node_spanned_pages;
477 struct memory_block *mem_blk = NULL;
480 for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
481 unsigned long section_nr = pfn_to_section_nr(pfn);
482 struct mem_section *mem_sect;
485 if (!present_section_nr(section_nr))
487 mem_sect = __nr_to_section(section_nr);
489 /* same memblock ? */
491 if ((section_nr >= mem_blk->start_section_nr) &&
492 (section_nr <= mem_blk->end_section_nr))
495 mem_blk = find_memory_block_hinted(mem_sect, mem_blk);
497 ret = register_mem_sect_under_node(mem_blk, nid);
501 /* discard ref obtained in find_memory_block() */
505 kobject_put(&mem_blk->dev.kobj);
509 #ifdef CONFIG_HUGETLBFS
511 * Handle per node hstate attribute [un]registration on transistions
512 * to/from memoryless state.
514 static void node_hugetlb_work(struct work_struct *work)
516 struct node *node = container_of(work, struct node, node_work);
519 * We only get here when a node transitions to/from memoryless state.
520 * We can detect which transition occurred by examining whether the
521 * node has memory now. hugetlb_register_node() already check this
522 * so we try to register the attributes. If that fails, then the
523 * node has transitioned to memoryless, try to unregister the
526 if (!hugetlb_register_node(node))
527 hugetlb_unregister_node(node);
530 static void init_node_hugetlb_work(int nid)
532 INIT_WORK(&node_devices[nid]->node_work, node_hugetlb_work);
535 static int node_memory_callback(struct notifier_block *self,
536 unsigned long action, void *arg)
538 struct memory_notify *mnb = arg;
539 int nid = mnb->status_change_nid;
545 * offload per node hstate [un]registration to a work thread
546 * when transitioning to/from memoryless state.
548 if (nid != NUMA_NO_NODE)
549 schedule_work(&node_devices[nid]->node_work);
552 case MEM_GOING_ONLINE:
553 case MEM_GOING_OFFLINE:
554 case MEM_CANCEL_ONLINE:
555 case MEM_CANCEL_OFFLINE:
562 #endif /* CONFIG_HUGETLBFS */
563 #else /* !CONFIG_MEMORY_HOTPLUG_SPARSE */
565 static int link_mem_sections(int nid) { return 0; }
566 #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
568 #if !defined(CONFIG_MEMORY_HOTPLUG_SPARSE) || \
569 !defined(CONFIG_HUGETLBFS)
570 static inline int node_memory_callback(struct notifier_block *self,
571 unsigned long action, void *arg)
576 static void init_node_hugetlb_work(int nid) { }
580 int register_one_node(int nid)
585 if (node_online(nid)) {
586 int p_node = parent_node(nid);
587 struct node *parent = NULL;
590 parent = node_devices[p_node];
592 node_devices[nid] = kzalloc(sizeof(struct node), GFP_KERNEL);
593 if (!node_devices[nid])
596 error = register_node(node_devices[nid], nid, parent);
598 /* link cpu under this node */
599 for_each_present_cpu(cpu) {
600 if (cpu_to_node(cpu) == nid)
601 register_cpu_under_node(cpu, nid);
604 /* link memory sections under this node */
605 error = link_mem_sections(nid);
607 /* initialize work queue for memory hot plug */
608 init_node_hugetlb_work(nid);
615 void unregister_one_node(int nid)
617 if (!node_devices[nid])
620 unregister_node(node_devices[nid]);
621 node_devices[nid] = NULL;
625 * node states attributes
628 static ssize_t print_nodes_state(enum node_states state, char *buf)
632 n = scnprintf(buf, PAGE_SIZE - 1, "%*pbl",
633 nodemask_pr_args(&node_states[state]));
640 struct device_attribute attr;
641 enum node_states state;
644 static ssize_t show_node_state(struct device *dev,
645 struct device_attribute *attr, char *buf)
647 struct node_attr *na = container_of(attr, struct node_attr, attr);
648 return print_nodes_state(na->state, buf);
651 #define _NODE_ATTR(name, state) \
652 { __ATTR(name, 0444, show_node_state, NULL), state }
654 static struct node_attr node_state_attr[] = {
655 [N_POSSIBLE] = _NODE_ATTR(possible, N_POSSIBLE),
656 [N_ONLINE] = _NODE_ATTR(online, N_ONLINE),
657 [N_NORMAL_MEMORY] = _NODE_ATTR(has_normal_memory, N_NORMAL_MEMORY),
658 #ifdef CONFIG_HIGHMEM
659 [N_HIGH_MEMORY] = _NODE_ATTR(has_high_memory, N_HIGH_MEMORY),
661 #ifdef CONFIG_MOVABLE_NODE
662 [N_MEMORY] = _NODE_ATTR(has_memory, N_MEMORY),
664 [N_CPU] = _NODE_ATTR(has_cpu, N_CPU),
667 static struct attribute *node_state_attrs[] = {
668 &node_state_attr[N_POSSIBLE].attr.attr,
669 &node_state_attr[N_ONLINE].attr.attr,
670 &node_state_attr[N_NORMAL_MEMORY].attr.attr,
671 #ifdef CONFIG_HIGHMEM
672 &node_state_attr[N_HIGH_MEMORY].attr.attr,
674 #ifdef CONFIG_MOVABLE_NODE
675 &node_state_attr[N_MEMORY].attr.attr,
677 &node_state_attr[N_CPU].attr.attr,
681 static struct attribute_group memory_root_attr_group = {
682 .attrs = node_state_attrs,
685 static const struct attribute_group *cpu_root_attr_groups[] = {
686 &memory_root_attr_group,
690 #define NODE_CALLBACK_PRI 2 /* lower than SLAB */
691 static int __init register_node_type(void)
695 BUILD_BUG_ON(ARRAY_SIZE(node_state_attr) != NR_NODE_STATES);
696 BUILD_BUG_ON(ARRAY_SIZE(node_state_attrs)-1 != NR_NODE_STATES);
698 ret = subsys_system_register(&node_subsys, cpu_root_attr_groups);
700 static struct notifier_block node_memory_callback_nb = {
701 .notifier_call = node_memory_callback,
702 .priority = NODE_CALLBACK_PRI,
704 register_hotmemory_notifier(&node_memory_callback_nb);
708 * Note: we're not going to unregister the node class if we fail
709 * to register the node state class attribute files.
713 postcore_initcall(register_node_type);