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 ssize_t n; 31 cpumask_var_t mask; 32 struct node *node_dev = to_node(dev); 33 34 /* 2008/04/07: buf currently PAGE_SIZE, need 9 chars per 32 bits. */ 35 BUILD_BUG_ON((NR_CPUS/32 * 9) > (PAGE_SIZE-1)); 36 37 if (!alloc_cpumask_var(&mask, GFP_KERNEL)) 38 return 0; 39 40 cpumask_and(mask, cpumask_of_node(node_dev->dev.id), cpu_online_mask); 41 n = cpumap_print_to_pagebuf(list, buf, mask); 42 free_cpumask_var(mask); 43 44 return n; 45 } 46 47 static inline ssize_t node_read_cpumask(struct device *dev, 48 struct device_attribute *attr, char *buf) 49 { 50 return node_read_cpumap(dev, false, buf); 51 } 52 static inline ssize_t node_read_cpulist(struct device *dev, 53 struct device_attribute *attr, char *buf) 54 { 55 return node_read_cpumap(dev, true, buf); 56 } 57 58 static DEVICE_ATTR(cpumap, S_IRUGO, node_read_cpumask, NULL); 59 static DEVICE_ATTR(cpulist, S_IRUGO, node_read_cpulist, NULL); 60 61 #define K(x) ((x) << (PAGE_SHIFT - 10)) 62 static ssize_t node_read_meminfo(struct device *dev, 63 struct device_attribute *attr, char *buf) 64 { 65 int n; 66 int nid = dev->id; 67 struct pglist_data *pgdat = NODE_DATA(nid); 68 struct sysinfo i; 69 70 si_meminfo_node(&i, nid); 71 n = sprintf(buf, 72 "Node %d MemTotal: %8lu kB\n" 73 "Node %d MemFree: %8lu kB\n" 74 "Node %d MemUsed: %8lu kB\n" 75 "Node %d Active: %8lu kB\n" 76 "Node %d Inactive: %8lu kB\n" 77 "Node %d Active(anon): %8lu kB\n" 78 "Node %d Inactive(anon): %8lu kB\n" 79 "Node %d Active(file): %8lu kB\n" 80 "Node %d Inactive(file): %8lu kB\n" 81 "Node %d Unevictable: %8lu kB\n" 82 "Node %d Mlocked: %8lu kB\n", 83 nid, K(i.totalram), 84 nid, K(i.freeram), 85 nid, K(i.totalram - i.freeram), 86 nid, K(node_page_state(pgdat, NR_ACTIVE_ANON) + 87 node_page_state(pgdat, NR_ACTIVE_FILE)), 88 nid, K(node_page_state(pgdat, NR_INACTIVE_ANON) + 89 node_page_state(pgdat, NR_INACTIVE_FILE)), 90 nid, K(node_page_state(pgdat, NR_ACTIVE_ANON)), 91 nid, K(node_page_state(pgdat, NR_INACTIVE_ANON)), 92 nid, K(node_page_state(pgdat, NR_ACTIVE_FILE)), 93 nid, K(node_page_state(pgdat, NR_INACTIVE_FILE)), 94 nid, K(node_page_state(pgdat, NR_UNEVICTABLE)), 95 nid, K(sum_zone_node_page_state(nid, NR_MLOCK))); 96 97 #ifdef CONFIG_HIGHMEM 98 n += sprintf(buf + n, 99 "Node %d HighTotal: %8lu kB\n" 100 "Node %d HighFree: %8lu kB\n" 101 "Node %d LowTotal: %8lu kB\n" 102 "Node %d LowFree: %8lu kB\n", 103 nid, K(i.totalhigh), 104 nid, K(i.freehigh), 105 nid, K(i.totalram - i.totalhigh), 106 nid, K(i.freeram - i.freehigh)); 107 #endif 108 n += sprintf(buf + n, 109 "Node %d Dirty: %8lu kB\n" 110 "Node %d Writeback: %8lu kB\n" 111 "Node %d FilePages: %8lu kB\n" 112 "Node %d Mapped: %8lu kB\n" 113 "Node %d AnonPages: %8lu kB\n" 114 "Node %d Shmem: %8lu kB\n" 115 "Node %d KernelStack: %8lu kB\n" 116 "Node %d PageTables: %8lu kB\n" 117 "Node %d NFS_Unstable: %8lu kB\n" 118 "Node %d Bounce: %8lu kB\n" 119 "Node %d WritebackTmp: %8lu kB\n" 120 "Node %d Slab: %8lu kB\n" 121 "Node %d SReclaimable: %8lu kB\n" 122 "Node %d SUnreclaim: %8lu kB\n" 123 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 124 "Node %d AnonHugePages: %8lu kB\n" 125 "Node %d ShmemHugePages: %8lu kB\n" 126 "Node %d ShmemPmdMapped: %8lu kB\n" 127 #endif 128 , 129 nid, K(node_page_state(pgdat, NR_FILE_DIRTY)), 130 nid, K(node_page_state(pgdat, NR_WRITEBACK)), 131 nid, K(node_page_state(pgdat, NR_FILE_PAGES)), 132 nid, K(node_page_state(pgdat, NR_FILE_MAPPED)), 133 nid, K(node_page_state(pgdat, NR_ANON_MAPPED)), 134 nid, K(i.sharedram), 135 nid, sum_zone_node_page_state(nid, NR_KERNEL_STACK_KB), 136 nid, K(sum_zone_node_page_state(nid, NR_PAGETABLE)), 137 nid, K(node_page_state(pgdat, NR_UNSTABLE_NFS)), 138 nid, K(sum_zone_node_page_state(nid, NR_BOUNCE)), 139 nid, K(node_page_state(pgdat, NR_WRITEBACK_TEMP)), 140 nid, K(node_page_state(pgdat, NR_SLAB_RECLAIMABLE) + 141 node_page_state(pgdat, NR_SLAB_UNRECLAIMABLE)), 142 nid, K(node_page_state(pgdat, NR_SLAB_RECLAIMABLE)), 143 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 144 nid, K(node_page_state(pgdat, NR_SLAB_UNRECLAIMABLE)), 145 nid, K(node_page_state(pgdat, NR_ANON_THPS) * 146 HPAGE_PMD_NR), 147 nid, K(node_page_state(pgdat, NR_SHMEM_THPS) * 148 HPAGE_PMD_NR), 149 nid, K(node_page_state(pgdat, NR_SHMEM_PMDMAPPED) * 150 HPAGE_PMD_NR)); 151 #else 152 nid, K(node_page_state(pgdat, NR_SLAB_UNRECLAIMABLE))); 153 #endif 154 n += hugetlb_report_node_meminfo(nid, buf + n); 155 return n; 156 } 157 158 #undef K 159 static DEVICE_ATTR(meminfo, S_IRUGO, node_read_meminfo, NULL); 160 161 static ssize_t node_read_numastat(struct device *dev, 162 struct device_attribute *attr, char *buf) 163 { 164 return sprintf(buf, 165 "numa_hit %lu\n" 166 "numa_miss %lu\n" 167 "numa_foreign %lu\n" 168 "interleave_hit %lu\n" 169 "local_node %lu\n" 170 "other_node %lu\n", 171 sum_zone_numa_state(dev->id, NUMA_HIT), 172 sum_zone_numa_state(dev->id, NUMA_MISS), 173 sum_zone_numa_state(dev->id, NUMA_FOREIGN), 174 sum_zone_numa_state(dev->id, NUMA_INTERLEAVE_HIT), 175 sum_zone_numa_state(dev->id, NUMA_LOCAL), 176 sum_zone_numa_state(dev->id, NUMA_OTHER)); 177 } 178 static DEVICE_ATTR(numastat, S_IRUGO, node_read_numastat, NULL); 179 180 static ssize_t node_read_vmstat(struct device *dev, 181 struct device_attribute *attr, char *buf) 182 { 183 int nid = dev->id; 184 struct pglist_data *pgdat = NODE_DATA(nid); 185 int i; 186 int n = 0; 187 188 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) 189 n += sprintf(buf+n, "%s %lu\n", vmstat_text[i], 190 sum_zone_node_page_state(nid, i)); 191 192 #ifdef CONFIG_NUMA 193 for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++) 194 n += sprintf(buf+n, "%s %lu\n", 195 vmstat_text[i + NR_VM_ZONE_STAT_ITEMS], 196 sum_zone_numa_state(nid, i)); 197 #endif 198 199 for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) 200 n += sprintf(buf+n, "%s %lu\n", 201 vmstat_text[i + NR_VM_ZONE_STAT_ITEMS + 202 NR_VM_NUMA_STAT_ITEMS], 203 node_page_state(pgdat, i)); 204 205 return n; 206 } 207 static DEVICE_ATTR(vmstat, S_IRUGO, node_read_vmstat, NULL); 208 209 static ssize_t node_read_distance(struct device *dev, 210 struct device_attribute *attr, char *buf) 211 { 212 int nid = dev->id; 213 int len = 0; 214 int i; 215 216 /* 217 * buf is currently PAGE_SIZE in length and each node needs 4 chars 218 * at the most (distance + space or newline). 219 */ 220 BUILD_BUG_ON(MAX_NUMNODES * 4 > PAGE_SIZE); 221 222 for_each_online_node(i) 223 len += sprintf(buf + len, "%s%d", i ? " " : "", node_distance(nid, i)); 224 225 len += sprintf(buf + len, "\n"); 226 return len; 227 } 228 static DEVICE_ATTR(distance, S_IRUGO, node_read_distance, NULL); 229 230 static struct attribute *node_dev_attrs[] = { 231 &dev_attr_cpumap.attr, 232 &dev_attr_cpulist.attr, 233 &dev_attr_meminfo.attr, 234 &dev_attr_numastat.attr, 235 &dev_attr_distance.attr, 236 &dev_attr_vmstat.attr, 237 NULL 238 }; 239 ATTRIBUTE_GROUPS(node_dev); 240 241 #ifdef CONFIG_HUGETLBFS 242 /* 243 * hugetlbfs per node attributes registration interface: 244 * When/if hugetlb[fs] subsystem initializes [sometime after this module], 245 * it will register its per node attributes for all online nodes with 246 * memory. It will also call register_hugetlbfs_with_node(), below, to 247 * register its attribute registration functions with this node driver. 248 * Once these hooks have been initialized, the node driver will call into 249 * the hugetlb module to [un]register attributes for hot-plugged nodes. 250 */ 251 static node_registration_func_t __hugetlb_register_node; 252 static node_registration_func_t __hugetlb_unregister_node; 253 254 static inline bool hugetlb_register_node(struct node *node) 255 { 256 if (__hugetlb_register_node && 257 node_state(node->dev.id, N_MEMORY)) { 258 __hugetlb_register_node(node); 259 return true; 260 } 261 return false; 262 } 263 264 static inline void hugetlb_unregister_node(struct node *node) 265 { 266 if (__hugetlb_unregister_node) 267 __hugetlb_unregister_node(node); 268 } 269 270 void register_hugetlbfs_with_node(node_registration_func_t doregister, 271 node_registration_func_t unregister) 272 { 273 __hugetlb_register_node = doregister; 274 __hugetlb_unregister_node = unregister; 275 } 276 #else 277 static inline void hugetlb_register_node(struct node *node) {} 278 279 static inline void hugetlb_unregister_node(struct node *node) {} 280 #endif 281 282 static void node_device_release(struct device *dev) 283 { 284 struct node *node = to_node(dev); 285 286 #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HUGETLBFS) 287 /* 288 * We schedule the work only when a memory section is 289 * onlined/offlined on this node. When we come here, 290 * all the memory on this node has been offlined, 291 * so we won't enqueue new work to this work. 292 * 293 * The work is using node->node_work, so we should 294 * flush work before freeing the memory. 295 */ 296 flush_work(&node->node_work); 297 #endif 298 kfree(node); 299 } 300 301 /* 302 * register_node - Setup a sysfs device for a node. 303 * @num - Node number to use when creating the device. 304 * 305 * Initialize and register the node device. 306 */ 307 static int register_node(struct node *node, int num) 308 { 309 int error; 310 311 node->dev.id = num; 312 node->dev.bus = &node_subsys; 313 node->dev.release = node_device_release; 314 node->dev.groups = node_dev_groups; 315 error = device_register(&node->dev); 316 317 if (!error){ 318 hugetlb_register_node(node); 319 320 compaction_register_node(node); 321 } 322 return error; 323 } 324 325 /** 326 * unregister_node - unregister a node device 327 * @node: node going away 328 * 329 * Unregisters a node device @node. All the devices on the node must be 330 * unregistered before calling this function. 331 */ 332 void unregister_node(struct node *node) 333 { 334 hugetlb_unregister_node(node); /* no-op, if memoryless node */ 335 336 device_unregister(&node->dev); 337 } 338 339 struct node *node_devices[MAX_NUMNODES]; 340 341 /* 342 * register cpu under node 343 */ 344 int register_cpu_under_node(unsigned int cpu, unsigned int nid) 345 { 346 int ret; 347 struct device *obj; 348 349 if (!node_online(nid)) 350 return 0; 351 352 obj = get_cpu_device(cpu); 353 if (!obj) 354 return 0; 355 356 ret = sysfs_create_link(&node_devices[nid]->dev.kobj, 357 &obj->kobj, 358 kobject_name(&obj->kobj)); 359 if (ret) 360 return ret; 361 362 return sysfs_create_link(&obj->kobj, 363 &node_devices[nid]->dev.kobj, 364 kobject_name(&node_devices[nid]->dev.kobj)); 365 } 366 367 int unregister_cpu_under_node(unsigned int cpu, unsigned int nid) 368 { 369 struct device *obj; 370 371 if (!node_online(nid)) 372 return 0; 373 374 obj = get_cpu_device(cpu); 375 if (!obj) 376 return 0; 377 378 sysfs_remove_link(&node_devices[nid]->dev.kobj, 379 kobject_name(&obj->kobj)); 380 sysfs_remove_link(&obj->kobj, 381 kobject_name(&node_devices[nid]->dev.kobj)); 382 383 return 0; 384 } 385 386 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE 387 static int __ref get_nid_for_pfn(unsigned long pfn) 388 { 389 if (!pfn_valid_within(pfn)) 390 return -1; 391 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT 392 if (system_state < SYSTEM_RUNNING) 393 return early_pfn_to_nid(pfn); 394 #endif 395 return pfn_to_nid(pfn); 396 } 397 398 /* register memory section under specified node if it spans that node */ 399 int register_mem_sect_under_node(struct memory_block *mem_blk, int nid) 400 { 401 int ret; 402 unsigned long pfn, sect_start_pfn, sect_end_pfn; 403 404 if (!mem_blk) 405 return -EFAULT; 406 if (!node_online(nid)) 407 return 0; 408 409 sect_start_pfn = section_nr_to_pfn(mem_blk->start_section_nr); 410 sect_end_pfn = section_nr_to_pfn(mem_blk->end_section_nr); 411 sect_end_pfn += PAGES_PER_SECTION - 1; 412 for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) { 413 int page_nid; 414 415 /* 416 * memory block could have several absent sections from start. 417 * skip pfn range from absent section 418 */ 419 if (!pfn_present(pfn)) { 420 pfn = round_down(pfn + PAGES_PER_SECTION, 421 PAGES_PER_SECTION) - 1; 422 continue; 423 } 424 425 page_nid = get_nid_for_pfn(pfn); 426 if (page_nid < 0) 427 continue; 428 if (page_nid != nid) 429 continue; 430 ret = sysfs_create_link_nowarn(&node_devices[nid]->dev.kobj, 431 &mem_blk->dev.kobj, 432 kobject_name(&mem_blk->dev.kobj)); 433 if (ret) 434 return ret; 435 436 return sysfs_create_link_nowarn(&mem_blk->dev.kobj, 437 &node_devices[nid]->dev.kobj, 438 kobject_name(&node_devices[nid]->dev.kobj)); 439 } 440 /* mem section does not span the specified node */ 441 return 0; 442 } 443 444 /* unregister memory section under all nodes that it spans */ 445 int unregister_mem_sect_under_nodes(struct memory_block *mem_blk, 446 unsigned long phys_index) 447 { 448 NODEMASK_ALLOC(nodemask_t, unlinked_nodes, GFP_KERNEL); 449 unsigned long pfn, sect_start_pfn, sect_end_pfn; 450 451 if (!mem_blk) { 452 NODEMASK_FREE(unlinked_nodes); 453 return -EFAULT; 454 } 455 if (!unlinked_nodes) 456 return -ENOMEM; 457 nodes_clear(*unlinked_nodes); 458 459 sect_start_pfn = section_nr_to_pfn(phys_index); 460 sect_end_pfn = sect_start_pfn + PAGES_PER_SECTION - 1; 461 for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) { 462 int nid; 463 464 nid = get_nid_for_pfn(pfn); 465 if (nid < 0) 466 continue; 467 if (!node_online(nid)) 468 continue; 469 if (node_test_and_set(nid, *unlinked_nodes)) 470 continue; 471 sysfs_remove_link(&node_devices[nid]->dev.kobj, 472 kobject_name(&mem_blk->dev.kobj)); 473 sysfs_remove_link(&mem_blk->dev.kobj, 474 kobject_name(&node_devices[nid]->dev.kobj)); 475 } 476 NODEMASK_FREE(unlinked_nodes); 477 return 0; 478 } 479 480 int link_mem_sections(int nid, unsigned long start_pfn, unsigned long nr_pages) 481 { 482 unsigned long end_pfn = start_pfn + nr_pages; 483 unsigned long pfn; 484 struct memory_block *mem_blk = NULL; 485 int err = 0; 486 487 for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) { 488 unsigned long section_nr = pfn_to_section_nr(pfn); 489 struct mem_section *mem_sect; 490 int ret; 491 492 if (!present_section_nr(section_nr)) 493 continue; 494 mem_sect = __nr_to_section(section_nr); 495 496 /* same memblock ? */ 497 if (mem_blk) 498 if ((section_nr >= mem_blk->start_section_nr) && 499 (section_nr <= mem_blk->end_section_nr)) 500 continue; 501 502 mem_blk = find_memory_block_hinted(mem_sect, mem_blk); 503 504 ret = register_mem_sect_under_node(mem_blk, nid); 505 if (!err) 506 err = ret; 507 508 /* discard ref obtained in find_memory_block() */ 509 } 510 511 if (mem_blk) 512 kobject_put(&mem_blk->dev.kobj); 513 return err; 514 } 515 516 #ifdef CONFIG_HUGETLBFS 517 /* 518 * Handle per node hstate attribute [un]registration on transistions 519 * to/from memoryless state. 520 */ 521 static void node_hugetlb_work(struct work_struct *work) 522 { 523 struct node *node = container_of(work, struct node, node_work); 524 525 /* 526 * We only get here when a node transitions to/from memoryless state. 527 * We can detect which transition occurred by examining whether the 528 * node has memory now. hugetlb_register_node() already check this 529 * so we try to register the attributes. If that fails, then the 530 * node has transitioned to memoryless, try to unregister the 531 * attributes. 532 */ 533 if (!hugetlb_register_node(node)) 534 hugetlb_unregister_node(node); 535 } 536 537 static void init_node_hugetlb_work(int nid) 538 { 539 INIT_WORK(&node_devices[nid]->node_work, node_hugetlb_work); 540 } 541 542 static int node_memory_callback(struct notifier_block *self, 543 unsigned long action, void *arg) 544 { 545 struct memory_notify *mnb = arg; 546 int nid = mnb->status_change_nid; 547 548 switch (action) { 549 case MEM_ONLINE: 550 case MEM_OFFLINE: 551 /* 552 * offload per node hstate [un]registration to a work thread 553 * when transitioning to/from memoryless state. 554 */ 555 if (nid != NUMA_NO_NODE) 556 schedule_work(&node_devices[nid]->node_work); 557 break; 558 559 case MEM_GOING_ONLINE: 560 case MEM_GOING_OFFLINE: 561 case MEM_CANCEL_ONLINE: 562 case MEM_CANCEL_OFFLINE: 563 default: 564 break; 565 } 566 567 return NOTIFY_OK; 568 } 569 #endif /* CONFIG_HUGETLBFS */ 570 #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */ 571 572 #if !defined(CONFIG_MEMORY_HOTPLUG_SPARSE) || \ 573 !defined(CONFIG_HUGETLBFS) 574 static inline int node_memory_callback(struct notifier_block *self, 575 unsigned long action, void *arg) 576 { 577 return NOTIFY_OK; 578 } 579 580 static void init_node_hugetlb_work(int nid) { } 581 582 #endif 583 584 int __register_one_node(int nid) 585 { 586 int error; 587 int cpu; 588 589 node_devices[nid] = kzalloc(sizeof(struct node), GFP_KERNEL); 590 if (!node_devices[nid]) 591 return -ENOMEM; 592 593 error = register_node(node_devices[nid], nid); 594 595 /* link cpu under this node */ 596 for_each_present_cpu(cpu) { 597 if (cpu_to_node(cpu) == nid) 598 register_cpu_under_node(cpu, nid); 599 } 600 601 /* initialize work queue for memory hot plug */ 602 init_node_hugetlb_work(nid); 603 604 return error; 605 } 606 607 void unregister_one_node(int nid) 608 { 609 if (!node_devices[nid]) 610 return; 611 612 unregister_node(node_devices[nid]); 613 node_devices[nid] = NULL; 614 } 615 616 /* 617 * node states attributes 618 */ 619 620 static ssize_t print_nodes_state(enum node_states state, char *buf) 621 { 622 int n; 623 624 n = scnprintf(buf, PAGE_SIZE - 1, "%*pbl", 625 nodemask_pr_args(&node_states[state])); 626 buf[n++] = '\n'; 627 buf[n] = '\0'; 628 return n; 629 } 630 631 struct node_attr { 632 struct device_attribute attr; 633 enum node_states state; 634 }; 635 636 static ssize_t show_node_state(struct device *dev, 637 struct device_attribute *attr, char *buf) 638 { 639 struct node_attr *na = container_of(attr, struct node_attr, attr); 640 return print_nodes_state(na->state, buf); 641 } 642 643 #define _NODE_ATTR(name, state) \ 644 { __ATTR(name, 0444, show_node_state, NULL), state } 645 646 static struct node_attr node_state_attr[] = { 647 [N_POSSIBLE] = _NODE_ATTR(possible, N_POSSIBLE), 648 [N_ONLINE] = _NODE_ATTR(online, N_ONLINE), 649 [N_NORMAL_MEMORY] = _NODE_ATTR(has_normal_memory, N_NORMAL_MEMORY), 650 #ifdef CONFIG_HIGHMEM 651 [N_HIGH_MEMORY] = _NODE_ATTR(has_high_memory, N_HIGH_MEMORY), 652 #endif 653 [N_MEMORY] = _NODE_ATTR(has_memory, N_MEMORY), 654 [N_CPU] = _NODE_ATTR(has_cpu, N_CPU), 655 }; 656 657 static struct attribute *node_state_attrs[] = { 658 &node_state_attr[N_POSSIBLE].attr.attr, 659 &node_state_attr[N_ONLINE].attr.attr, 660 &node_state_attr[N_NORMAL_MEMORY].attr.attr, 661 #ifdef CONFIG_HIGHMEM 662 &node_state_attr[N_HIGH_MEMORY].attr.attr, 663 #endif 664 &node_state_attr[N_MEMORY].attr.attr, 665 &node_state_attr[N_CPU].attr.attr, 666 NULL 667 }; 668 669 static struct attribute_group memory_root_attr_group = { 670 .attrs = node_state_attrs, 671 }; 672 673 static 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 */ 679 static 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 } 701 postcore_initcall(register_node_type); 702