1 /* 2 * Basic Node interface support 3 */ 4 5 #include <linux/module.h> 6 #include <linux/init.h> 7 #include <linux/mm.h> 8 #include <linux/memory.h> 9 #include <linux/vmstat.h> 10 #include <linux/notifier.h> 11 #include <linux/node.h> 12 #include <linux/hugetlb.h> 13 #include <linux/compaction.h> 14 #include <linux/cpumask.h> 15 #include <linux/topology.h> 16 #include <linux/nodemask.h> 17 #include <linux/cpu.h> 18 #include <linux/device.h> 19 #include <linux/swap.h> 20 #include <linux/slab.h> 21 22 static struct bus_type node_subsys = { 23 .name = "node", 24 .dev_name = "node", 25 }; 26 27 28 static ssize_t node_read_cpumap(struct device *dev, bool list, char *buf) 29 { 30 struct node *node_dev = to_node(dev); 31 const struct cpumask *mask = cpumask_of_node(node_dev->dev.id); 32 33 /* 2008/04/07: buf currently PAGE_SIZE, need 9 chars per 32 bits. */ 34 BUILD_BUG_ON((NR_CPUS/32 * 9) > (PAGE_SIZE-1)); 35 36 return cpumap_print_to_pagebuf(list, buf, mask); 37 } 38 39 static inline ssize_t node_read_cpumask(struct device *dev, 40 struct device_attribute *attr, char *buf) 41 { 42 return node_read_cpumap(dev, false, buf); 43 } 44 static inline ssize_t node_read_cpulist(struct device *dev, 45 struct device_attribute *attr, char *buf) 46 { 47 return node_read_cpumap(dev, true, buf); 48 } 49 50 static DEVICE_ATTR(cpumap, S_IRUGO, node_read_cpumask, NULL); 51 static DEVICE_ATTR(cpulist, S_IRUGO, node_read_cpulist, NULL); 52 53 #define K(x) ((x) << (PAGE_SHIFT - 10)) 54 static ssize_t node_read_meminfo(struct device *dev, 55 struct device_attribute *attr, char *buf) 56 { 57 int n; 58 int nid = dev->id; 59 struct 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 146 static DEVICE_ATTR(meminfo, S_IRUGO, node_read_meminfo, NULL); 147 148 static 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 } 165 static DEVICE_ATTR(numastat, S_IRUGO, node_read_numastat, NULL); 166 167 static 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 } 180 static DEVICE_ATTR(vmstat, S_IRUGO, node_read_vmstat, NULL); 181 182 static 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 } 201 static DEVICE_ATTR(distance, S_IRUGO, node_read_distance, NULL); 202 203 static 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 }; 212 ATTRIBUTE_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 */ 224 static node_registration_func_t __hugetlb_register_node; 225 static node_registration_func_t __hugetlb_unregister_node; 226 227 static 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 } 236 237 static inline void hugetlb_unregister_node(struct node *node) 238 { 239 if (__hugetlb_unregister_node) 240 __hugetlb_unregister_node(node); 241 } 242 243 void 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 250 static inline void hugetlb_register_node(struct node *node) {} 251 252 static inline void hugetlb_unregister_node(struct node *node) {} 253 #endif 254 255 static 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 */ 280 static 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 */ 305 void unregister_node(struct node *node) 306 { 307 hugetlb_unregister_node(node); /* no-op, if memoryless node */ 308 309 device_unregister(&node->dev); 310 } 311 312 struct node *node_devices[MAX_NUMNODES]; 313 314 /* 315 * register cpu under node 316 */ 317 int 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 } 339 340 int 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) 361 362 static int get_nid_for_pfn(unsigned long pfn) 363 { 364 struct page *page; 365 366 if (!pfn_valid_within(pfn)) 367 return -1; 368 page = pfn_to_page(pfn); 369 if (!page_initialized(page)) 370 return -1; 371 return pfn_to_nid(pfn); 372 } 373 374 /* register memory section under specified node if it spans that node */ 375 int register_mem_sect_under_node(struct memory_block *mem_blk, int nid) 376 { 377 int ret; 378 unsigned long pfn, sect_start_pfn, sect_end_pfn; 379 380 if (!mem_blk) 381 return -EFAULT; 382 if (!node_online(nid)) 383 return 0; 384 385 sect_start_pfn = section_nr_to_pfn(mem_blk->start_section_nr); 386 sect_end_pfn = section_nr_to_pfn(mem_blk->end_section_nr); 387 sect_end_pfn += PAGES_PER_SECTION - 1; 388 for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) { 389 int page_nid; 390 391 page_nid = get_nid_for_pfn(pfn); 392 if (page_nid < 0) 393 continue; 394 if (page_nid != nid) 395 continue; 396 ret = sysfs_create_link_nowarn(&node_devices[nid]->dev.kobj, 397 &mem_blk->dev.kobj, 398 kobject_name(&mem_blk->dev.kobj)); 399 if (ret) 400 return ret; 401 402 return sysfs_create_link_nowarn(&mem_blk->dev.kobj, 403 &node_devices[nid]->dev.kobj, 404 kobject_name(&node_devices[nid]->dev.kobj)); 405 } 406 /* mem section does not span the specified node */ 407 return 0; 408 } 409 410 /* unregister memory section under all nodes that it spans */ 411 int unregister_mem_sect_under_nodes(struct memory_block *mem_blk, 412 unsigned long phys_index) 413 { 414 NODEMASK_ALLOC(nodemask_t, unlinked_nodes, GFP_KERNEL); 415 unsigned long pfn, sect_start_pfn, sect_end_pfn; 416 417 if (!mem_blk) { 418 NODEMASK_FREE(unlinked_nodes); 419 return -EFAULT; 420 } 421 if (!unlinked_nodes) 422 return -ENOMEM; 423 nodes_clear(*unlinked_nodes); 424 425 sect_start_pfn = section_nr_to_pfn(phys_index); 426 sect_end_pfn = sect_start_pfn + PAGES_PER_SECTION - 1; 427 for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) { 428 int nid; 429 430 nid = get_nid_for_pfn(pfn); 431 if (nid < 0) 432 continue; 433 if (!node_online(nid)) 434 continue; 435 if (node_test_and_set(nid, *unlinked_nodes)) 436 continue; 437 sysfs_remove_link(&node_devices[nid]->dev.kobj, 438 kobject_name(&mem_blk->dev.kobj)); 439 sysfs_remove_link(&mem_blk->dev.kobj, 440 kobject_name(&node_devices[nid]->dev.kobj)); 441 } 442 NODEMASK_FREE(unlinked_nodes); 443 return 0; 444 } 445 446 static int link_mem_sections(int nid) 447 { 448 unsigned long start_pfn = NODE_DATA(nid)->node_start_pfn; 449 unsigned long end_pfn = start_pfn + NODE_DATA(nid)->node_spanned_pages; 450 unsigned long pfn; 451 struct memory_block *mem_blk = NULL; 452 int err = 0; 453 454 for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) { 455 unsigned long section_nr = pfn_to_section_nr(pfn); 456 struct mem_section *mem_sect; 457 int ret; 458 459 if (!present_section_nr(section_nr)) 460 continue; 461 mem_sect = __nr_to_section(section_nr); 462 463 /* same memblock ? */ 464 if (mem_blk) 465 if ((section_nr >= mem_blk->start_section_nr) && 466 (section_nr <= mem_blk->end_section_nr)) 467 continue; 468 469 mem_blk = find_memory_block_hinted(mem_sect, mem_blk); 470 471 ret = register_mem_sect_under_node(mem_blk, nid); 472 if (!err) 473 err = ret; 474 475 /* discard ref obtained in find_memory_block() */ 476 } 477 478 if (mem_blk) 479 kobject_put(&mem_blk->dev.kobj); 480 return err; 481 } 482 483 #ifdef CONFIG_HUGETLBFS 484 /* 485 * Handle per node hstate attribute [un]registration on transistions 486 * to/from memoryless state. 487 */ 488 static void node_hugetlb_work(struct work_struct *work) 489 { 490 struct node *node = container_of(work, struct node, node_work); 491 492 /* 493 * We only get here when a node transitions to/from memoryless state. 494 * We can detect which transition occurred by examining whether the 495 * node has memory now. hugetlb_register_node() already check this 496 * so we try to register the attributes. If that fails, then the 497 * node has transitioned to memoryless, try to unregister the 498 * attributes. 499 */ 500 if (!hugetlb_register_node(node)) 501 hugetlb_unregister_node(node); 502 } 503 504 static void init_node_hugetlb_work(int nid) 505 { 506 INIT_WORK(&node_devices[nid]->node_work, node_hugetlb_work); 507 } 508 509 static int node_memory_callback(struct notifier_block *self, 510 unsigned long action, void *arg) 511 { 512 struct memory_notify *mnb = arg; 513 int nid = mnb->status_change_nid; 514 515 switch (action) { 516 case MEM_ONLINE: 517 case MEM_OFFLINE: 518 /* 519 * offload per node hstate [un]registration to a work thread 520 * when transitioning to/from memoryless state. 521 */ 522 if (nid != NUMA_NO_NODE) 523 schedule_work(&node_devices[nid]->node_work); 524 break; 525 526 case MEM_GOING_ONLINE: 527 case MEM_GOING_OFFLINE: 528 case MEM_CANCEL_ONLINE: 529 case MEM_CANCEL_OFFLINE: 530 default: 531 break; 532 } 533 534 return NOTIFY_OK; 535 } 536 #endif /* CONFIG_HUGETLBFS */ 537 #else /* !CONFIG_MEMORY_HOTPLUG_SPARSE */ 538 539 static int link_mem_sections(int nid) { return 0; } 540 #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */ 541 542 #if !defined(CONFIG_MEMORY_HOTPLUG_SPARSE) || \ 543 !defined(CONFIG_HUGETLBFS) 544 static inline int node_memory_callback(struct notifier_block *self, 545 unsigned long action, void *arg) 546 { 547 return NOTIFY_OK; 548 } 549 550 static void init_node_hugetlb_work(int nid) { } 551 552 #endif 553 554 int register_one_node(int nid) 555 { 556 int error = 0; 557 int cpu; 558 559 if (node_online(nid)) { 560 int p_node = parent_node(nid); 561 struct node *parent = NULL; 562 563 if (p_node != nid) 564 parent = node_devices[p_node]; 565 566 node_devices[nid] = kzalloc(sizeof(struct node), GFP_KERNEL); 567 if (!node_devices[nid]) 568 return -ENOMEM; 569 570 error = register_node(node_devices[nid], nid, parent); 571 572 /* link cpu under this node */ 573 for_each_present_cpu(cpu) { 574 if (cpu_to_node(cpu) == nid) 575 register_cpu_under_node(cpu, nid); 576 } 577 578 /* link memory sections under this node */ 579 error = link_mem_sections(nid); 580 581 /* initialize work queue for memory hot plug */ 582 init_node_hugetlb_work(nid); 583 } 584 585 return error; 586 587 } 588 589 void unregister_one_node(int nid) 590 { 591 if (!node_devices[nid]) 592 return; 593 594 unregister_node(node_devices[nid]); 595 node_devices[nid] = NULL; 596 } 597 598 /* 599 * node states attributes 600 */ 601 602 static ssize_t print_nodes_state(enum node_states state, char *buf) 603 { 604 int n; 605 606 n = scnprintf(buf, PAGE_SIZE - 1, "%*pbl", 607 nodemask_pr_args(&node_states[state])); 608 buf[n++] = '\n'; 609 buf[n] = '\0'; 610 return n; 611 } 612 613 struct node_attr { 614 struct device_attribute attr; 615 enum node_states state; 616 }; 617 618 static ssize_t show_node_state(struct device *dev, 619 struct device_attribute *attr, char *buf) 620 { 621 struct node_attr *na = container_of(attr, struct node_attr, attr); 622 return print_nodes_state(na->state, buf); 623 } 624 625 #define _NODE_ATTR(name, state) \ 626 { __ATTR(name, 0444, show_node_state, NULL), state } 627 628 static struct node_attr node_state_attr[] = { 629 [N_POSSIBLE] = _NODE_ATTR(possible, N_POSSIBLE), 630 [N_ONLINE] = _NODE_ATTR(online, N_ONLINE), 631 [N_NORMAL_MEMORY] = _NODE_ATTR(has_normal_memory, N_NORMAL_MEMORY), 632 #ifdef CONFIG_HIGHMEM 633 [N_HIGH_MEMORY] = _NODE_ATTR(has_high_memory, N_HIGH_MEMORY), 634 #endif 635 #ifdef CONFIG_MOVABLE_NODE 636 [N_MEMORY] = _NODE_ATTR(has_memory, N_MEMORY), 637 #endif 638 [N_CPU] = _NODE_ATTR(has_cpu, N_CPU), 639 }; 640 641 static struct attribute *node_state_attrs[] = { 642 &node_state_attr[N_POSSIBLE].attr.attr, 643 &node_state_attr[N_ONLINE].attr.attr, 644 &node_state_attr[N_NORMAL_MEMORY].attr.attr, 645 #ifdef CONFIG_HIGHMEM 646 &node_state_attr[N_HIGH_MEMORY].attr.attr, 647 #endif 648 #ifdef CONFIG_MOVABLE_NODE 649 &node_state_attr[N_MEMORY].attr.attr, 650 #endif 651 &node_state_attr[N_CPU].attr.attr, 652 NULL 653 }; 654 655 static struct attribute_group memory_root_attr_group = { 656 .attrs = node_state_attrs, 657 }; 658 659 static const struct attribute_group *cpu_root_attr_groups[] = { 660 &memory_root_attr_group, 661 NULL, 662 }; 663 664 #define NODE_CALLBACK_PRI 2 /* lower than SLAB */ 665 static int __init register_node_type(void) 666 { 667 int ret; 668 669 BUILD_BUG_ON(ARRAY_SIZE(node_state_attr) != NR_NODE_STATES); 670 BUILD_BUG_ON(ARRAY_SIZE(node_state_attrs)-1 != NR_NODE_STATES); 671 672 ret = subsys_system_register(&node_subsys, cpu_root_attr_groups); 673 if (!ret) { 674 static struct notifier_block node_memory_callback_nb = { 675 .notifier_call = node_memory_callback, 676 .priority = NODE_CALLBACK_PRI, 677 }; 678 register_hotmemory_notifier(&node_memory_callback_nb); 679 } 680 681 /* 682 * Note: we're not going to unregister the node class if we fail 683 * to register the node state class attribute files. 684 */ 685 return ret; 686 } 687 postcore_initcall(register_node_type); 688