1 /* 2 * drivers/base/node.c - basic Node class support 3 */ 4 5 #include <linux/sysdev.h> 6 #include <linux/module.h> 7 #include <linux/init.h> 8 #include <linux/mm.h> 9 #include <linux/memory.h> 10 #include <linux/node.h> 11 #include <linux/hugetlb.h> 12 #include <linux/compaction.h> 13 #include <linux/cpumask.h> 14 #include <linux/topology.h> 15 #include <linux/nodemask.h> 16 #include <linux/cpu.h> 17 #include <linux/device.h> 18 #include <linux/swap.h> 19 #include <linux/slab.h> 20 21 static struct sysdev_class_attribute *node_state_attrs[]; 22 23 static struct sysdev_class node_class = { 24 .name = "node", 25 .attrs = node_state_attrs, 26 }; 27 28 29 static ssize_t node_read_cpumap(struct sys_device *dev, int type, char *buf) 30 { 31 struct node *node_dev = to_node(dev); 32 const struct cpumask *mask = cpumask_of_node(node_dev->sysdev.id); 33 int len; 34 35 /* 2008/04/07: buf currently PAGE_SIZE, need 9 chars per 32 bits. */ 36 BUILD_BUG_ON((NR_CPUS/32 * 9) > (PAGE_SIZE-1)); 37 38 len = type? 39 cpulist_scnprintf(buf, PAGE_SIZE-2, mask) : 40 cpumask_scnprintf(buf, PAGE_SIZE-2, mask); 41 buf[len++] = '\n'; 42 buf[len] = '\0'; 43 return len; 44 } 45 46 static inline ssize_t node_read_cpumask(struct sys_device *dev, 47 struct sysdev_attribute *attr, char *buf) 48 { 49 return node_read_cpumap(dev, 0, buf); 50 } 51 static inline ssize_t node_read_cpulist(struct sys_device *dev, 52 struct sysdev_attribute *attr, char *buf) 53 { 54 return node_read_cpumap(dev, 1, buf); 55 } 56 57 static SYSDEV_ATTR(cpumap, S_IRUGO, node_read_cpumask, NULL); 58 static SYSDEV_ATTR(cpulist, S_IRUGO, node_read_cpulist, NULL); 59 60 #define K(x) ((x) << (PAGE_SHIFT - 10)) 61 static ssize_t node_read_meminfo(struct sys_device * dev, 62 struct sysdev_attribute *attr, char * buf) 63 { 64 int n; 65 int nid = dev->id; 66 struct sysinfo i; 67 68 si_meminfo_node(&i, nid); 69 n = sprintf(buf, 70 "Node %d MemTotal: %8lu kB\n" 71 "Node %d MemFree: %8lu kB\n" 72 "Node %d MemUsed: %8lu kB\n" 73 "Node %d Active: %8lu kB\n" 74 "Node %d Inactive: %8lu kB\n" 75 "Node %d Active(anon): %8lu kB\n" 76 "Node %d Inactive(anon): %8lu kB\n" 77 "Node %d Active(file): %8lu kB\n" 78 "Node %d Inactive(file): %8lu kB\n" 79 "Node %d Unevictable: %8lu kB\n" 80 "Node %d Mlocked: %8lu kB\n", 81 nid, K(i.totalram), 82 nid, K(i.freeram), 83 nid, K(i.totalram - i.freeram), 84 nid, K(node_page_state(nid, NR_ACTIVE_ANON) + 85 node_page_state(nid, NR_ACTIVE_FILE)), 86 nid, K(node_page_state(nid, NR_INACTIVE_ANON) + 87 node_page_state(nid, NR_INACTIVE_FILE)), 88 nid, K(node_page_state(nid, NR_ACTIVE_ANON)), 89 nid, K(node_page_state(nid, NR_INACTIVE_ANON)), 90 nid, K(node_page_state(nid, NR_ACTIVE_FILE)), 91 nid, K(node_page_state(nid, NR_INACTIVE_FILE)), 92 nid, K(node_page_state(nid, NR_UNEVICTABLE)), 93 nid, K(node_page_state(nid, NR_MLOCK))); 94 95 #ifdef CONFIG_HIGHMEM 96 n += sprintf(buf + n, 97 "Node %d HighTotal: %8lu kB\n" 98 "Node %d HighFree: %8lu kB\n" 99 "Node %d LowTotal: %8lu kB\n" 100 "Node %d LowFree: %8lu kB\n", 101 nid, K(i.totalhigh), 102 nid, K(i.freehigh), 103 nid, K(i.totalram - i.totalhigh), 104 nid, K(i.freeram - i.freehigh)); 105 #endif 106 n += sprintf(buf + n, 107 "Node %d Dirty: %8lu kB\n" 108 "Node %d Writeback: %8lu kB\n" 109 "Node %d FilePages: %8lu kB\n" 110 "Node %d Mapped: %8lu kB\n" 111 "Node %d AnonPages: %8lu kB\n" 112 "Node %d Shmem: %8lu kB\n" 113 "Node %d KernelStack: %8lu kB\n" 114 "Node %d PageTables: %8lu kB\n" 115 "Node %d NFS_Unstable: %8lu kB\n" 116 "Node %d Bounce: %8lu kB\n" 117 "Node %d WritebackTmp: %8lu kB\n" 118 "Node %d Slab: %8lu kB\n" 119 "Node %d SReclaimable: %8lu kB\n" 120 "Node %d SUnreclaim: %8lu kB\n", 121 nid, K(node_page_state(nid, NR_FILE_DIRTY)), 122 nid, K(node_page_state(nid, NR_WRITEBACK)), 123 nid, K(node_page_state(nid, NR_FILE_PAGES)), 124 nid, K(node_page_state(nid, NR_FILE_MAPPED)), 125 nid, K(node_page_state(nid, NR_ANON_PAGES)), 126 nid, K(node_page_state(nid, NR_SHMEM)), 127 nid, node_page_state(nid, NR_KERNEL_STACK) * 128 THREAD_SIZE / 1024, 129 nid, K(node_page_state(nid, NR_PAGETABLE)), 130 nid, K(node_page_state(nid, NR_UNSTABLE_NFS)), 131 nid, K(node_page_state(nid, NR_BOUNCE)), 132 nid, K(node_page_state(nid, NR_WRITEBACK_TEMP)), 133 nid, K(node_page_state(nid, NR_SLAB_RECLAIMABLE) + 134 node_page_state(nid, NR_SLAB_UNRECLAIMABLE)), 135 nid, K(node_page_state(nid, NR_SLAB_RECLAIMABLE)), 136 nid, K(node_page_state(nid, NR_SLAB_UNRECLAIMABLE))); 137 n += hugetlb_report_node_meminfo(nid, buf + n); 138 return n; 139 } 140 141 #undef K 142 static SYSDEV_ATTR(meminfo, S_IRUGO, node_read_meminfo, NULL); 143 144 static ssize_t node_read_numastat(struct sys_device * dev, 145 struct sysdev_attribute *attr, char * buf) 146 { 147 return sprintf(buf, 148 "numa_hit %lu\n" 149 "numa_miss %lu\n" 150 "numa_foreign %lu\n" 151 "interleave_hit %lu\n" 152 "local_node %lu\n" 153 "other_node %lu\n", 154 node_page_state(dev->id, NUMA_HIT), 155 node_page_state(dev->id, NUMA_MISS), 156 node_page_state(dev->id, NUMA_FOREIGN), 157 node_page_state(dev->id, NUMA_INTERLEAVE_HIT), 158 node_page_state(dev->id, NUMA_LOCAL), 159 node_page_state(dev->id, NUMA_OTHER)); 160 } 161 static SYSDEV_ATTR(numastat, S_IRUGO, node_read_numastat, NULL); 162 163 static ssize_t node_read_vmstat(struct sys_device *dev, 164 struct sysdev_attribute *attr, char *buf) 165 { 166 int nid = dev->id; 167 return sprintf(buf, 168 "nr_written %lu\n" 169 "nr_dirtied %lu\n", 170 node_page_state(nid, NR_WRITTEN), 171 node_page_state(nid, NR_DIRTIED)); 172 } 173 static SYSDEV_ATTR(vmstat, S_IRUGO, node_read_vmstat, NULL); 174 175 static ssize_t node_read_distance(struct sys_device * dev, 176 struct sysdev_attribute *attr, char * buf) 177 { 178 int nid = dev->id; 179 int len = 0; 180 int i; 181 182 /* 183 * buf is currently PAGE_SIZE in length and each node needs 4 chars 184 * at the most (distance + space or newline). 185 */ 186 BUILD_BUG_ON(MAX_NUMNODES * 4 > PAGE_SIZE); 187 188 for_each_online_node(i) 189 len += sprintf(buf + len, "%s%d", i ? " " : "", node_distance(nid, i)); 190 191 len += sprintf(buf + len, "\n"); 192 return len; 193 } 194 static SYSDEV_ATTR(distance, S_IRUGO, node_read_distance, NULL); 195 196 #ifdef CONFIG_HUGETLBFS 197 /* 198 * hugetlbfs per node attributes registration interface: 199 * When/if hugetlb[fs] subsystem initializes [sometime after this module], 200 * it will register its per node attributes for all online nodes with 201 * memory. It will also call register_hugetlbfs_with_node(), below, to 202 * register its attribute registration functions with this node driver. 203 * Once these hooks have been initialized, the node driver will call into 204 * the hugetlb module to [un]register attributes for hot-plugged nodes. 205 */ 206 static node_registration_func_t __hugetlb_register_node; 207 static node_registration_func_t __hugetlb_unregister_node; 208 209 static inline bool hugetlb_register_node(struct node *node) 210 { 211 if (__hugetlb_register_node && 212 node_state(node->sysdev.id, N_HIGH_MEMORY)) { 213 __hugetlb_register_node(node); 214 return true; 215 } 216 return false; 217 } 218 219 static inline void hugetlb_unregister_node(struct node *node) 220 { 221 if (__hugetlb_unregister_node) 222 __hugetlb_unregister_node(node); 223 } 224 225 void register_hugetlbfs_with_node(node_registration_func_t doregister, 226 node_registration_func_t unregister) 227 { 228 __hugetlb_register_node = doregister; 229 __hugetlb_unregister_node = unregister; 230 } 231 #else 232 static inline void hugetlb_register_node(struct node *node) {} 233 234 static inline void hugetlb_unregister_node(struct node *node) {} 235 #endif 236 237 238 /* 239 * register_node - Setup a sysfs device for a node. 240 * @num - Node number to use when creating the device. 241 * 242 * Initialize and register the node device. 243 */ 244 int register_node(struct node *node, int num, struct node *parent) 245 { 246 int error; 247 248 node->sysdev.id = num; 249 node->sysdev.cls = &node_class; 250 error = sysdev_register(&node->sysdev); 251 252 if (!error){ 253 sysdev_create_file(&node->sysdev, &attr_cpumap); 254 sysdev_create_file(&node->sysdev, &attr_cpulist); 255 sysdev_create_file(&node->sysdev, &attr_meminfo); 256 sysdev_create_file(&node->sysdev, &attr_numastat); 257 sysdev_create_file(&node->sysdev, &attr_distance); 258 sysdev_create_file(&node->sysdev, &attr_vmstat); 259 260 scan_unevictable_register_node(node); 261 262 hugetlb_register_node(node); 263 264 compaction_register_node(node); 265 } 266 return error; 267 } 268 269 /** 270 * unregister_node - unregister a node device 271 * @node: node going away 272 * 273 * Unregisters a node device @node. All the devices on the node must be 274 * unregistered before calling this function. 275 */ 276 void unregister_node(struct node *node) 277 { 278 sysdev_remove_file(&node->sysdev, &attr_cpumap); 279 sysdev_remove_file(&node->sysdev, &attr_cpulist); 280 sysdev_remove_file(&node->sysdev, &attr_meminfo); 281 sysdev_remove_file(&node->sysdev, &attr_numastat); 282 sysdev_remove_file(&node->sysdev, &attr_distance); 283 sysdev_remove_file(&node->sysdev, &attr_vmstat); 284 285 scan_unevictable_unregister_node(node); 286 hugetlb_unregister_node(node); /* no-op, if memoryless node */ 287 288 sysdev_unregister(&node->sysdev); 289 } 290 291 struct node node_devices[MAX_NUMNODES]; 292 293 /* 294 * register cpu under node 295 */ 296 int register_cpu_under_node(unsigned int cpu, unsigned int nid) 297 { 298 int ret; 299 struct sys_device *obj; 300 301 if (!node_online(nid)) 302 return 0; 303 304 obj = get_cpu_sysdev(cpu); 305 if (!obj) 306 return 0; 307 308 ret = sysfs_create_link(&node_devices[nid].sysdev.kobj, 309 &obj->kobj, 310 kobject_name(&obj->kobj)); 311 if (ret) 312 return ret; 313 314 return sysfs_create_link(&obj->kobj, 315 &node_devices[nid].sysdev.kobj, 316 kobject_name(&node_devices[nid].sysdev.kobj)); 317 } 318 319 int unregister_cpu_under_node(unsigned int cpu, unsigned int nid) 320 { 321 struct sys_device *obj; 322 323 if (!node_online(nid)) 324 return 0; 325 326 obj = get_cpu_sysdev(cpu); 327 if (!obj) 328 return 0; 329 330 sysfs_remove_link(&node_devices[nid].sysdev.kobj, 331 kobject_name(&obj->kobj)); 332 sysfs_remove_link(&obj->kobj, 333 kobject_name(&node_devices[nid].sysdev.kobj)); 334 335 return 0; 336 } 337 338 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE 339 #define page_initialized(page) (page->lru.next) 340 341 static int get_nid_for_pfn(unsigned long pfn) 342 { 343 struct page *page; 344 345 if (!pfn_valid_within(pfn)) 346 return -1; 347 page = pfn_to_page(pfn); 348 if (!page_initialized(page)) 349 return -1; 350 return pfn_to_nid(pfn); 351 } 352 353 /* register memory section under specified node if it spans that node */ 354 int register_mem_sect_under_node(struct memory_block *mem_blk, int nid) 355 { 356 int ret; 357 unsigned long pfn, sect_start_pfn, sect_end_pfn; 358 359 if (!mem_blk) 360 return -EFAULT; 361 if (!node_online(nid)) 362 return 0; 363 sect_start_pfn = section_nr_to_pfn(mem_blk->phys_index); 364 sect_end_pfn = sect_start_pfn + PAGES_PER_SECTION - 1; 365 for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) { 366 int page_nid; 367 368 page_nid = get_nid_for_pfn(pfn); 369 if (page_nid < 0) 370 continue; 371 if (page_nid != nid) 372 continue; 373 ret = sysfs_create_link_nowarn(&node_devices[nid].sysdev.kobj, 374 &mem_blk->sysdev.kobj, 375 kobject_name(&mem_blk->sysdev.kobj)); 376 if (ret) 377 return ret; 378 379 return sysfs_create_link_nowarn(&mem_blk->sysdev.kobj, 380 &node_devices[nid].sysdev.kobj, 381 kobject_name(&node_devices[nid].sysdev.kobj)); 382 } 383 /* mem section does not span the specified node */ 384 return 0; 385 } 386 387 /* unregister memory section under all nodes that it spans */ 388 int unregister_mem_sect_under_nodes(struct memory_block *mem_blk) 389 { 390 NODEMASK_ALLOC(nodemask_t, unlinked_nodes, GFP_KERNEL); 391 unsigned long pfn, sect_start_pfn, sect_end_pfn; 392 393 if (!mem_blk) { 394 NODEMASK_FREE(unlinked_nodes); 395 return -EFAULT; 396 } 397 if (!unlinked_nodes) 398 return -ENOMEM; 399 nodes_clear(*unlinked_nodes); 400 sect_start_pfn = section_nr_to_pfn(mem_blk->phys_index); 401 sect_end_pfn = sect_start_pfn + PAGES_PER_SECTION - 1; 402 for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) { 403 int nid; 404 405 nid = get_nid_for_pfn(pfn); 406 if (nid < 0) 407 continue; 408 if (!node_online(nid)) 409 continue; 410 if (node_test_and_set(nid, *unlinked_nodes)) 411 continue; 412 sysfs_remove_link(&node_devices[nid].sysdev.kobj, 413 kobject_name(&mem_blk->sysdev.kobj)); 414 sysfs_remove_link(&mem_blk->sysdev.kobj, 415 kobject_name(&node_devices[nid].sysdev.kobj)); 416 } 417 NODEMASK_FREE(unlinked_nodes); 418 return 0; 419 } 420 421 static int link_mem_sections(int nid) 422 { 423 unsigned long start_pfn = NODE_DATA(nid)->node_start_pfn; 424 unsigned long end_pfn = start_pfn + NODE_DATA(nid)->node_spanned_pages; 425 unsigned long pfn; 426 struct memory_block *mem_blk = NULL; 427 int err = 0; 428 429 for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) { 430 unsigned long section_nr = pfn_to_section_nr(pfn); 431 struct mem_section *mem_sect; 432 int ret; 433 434 if (!present_section_nr(section_nr)) 435 continue; 436 mem_sect = __nr_to_section(section_nr); 437 mem_blk = find_memory_block_hinted(mem_sect, mem_blk); 438 ret = register_mem_sect_under_node(mem_blk, nid); 439 if (!err) 440 err = ret; 441 442 /* discard ref obtained in find_memory_block() */ 443 } 444 445 if (mem_blk) 446 kobject_put(&mem_blk->sysdev.kobj); 447 return err; 448 } 449 450 #ifdef CONFIG_HUGETLBFS 451 /* 452 * Handle per node hstate attribute [un]registration on transistions 453 * to/from memoryless state. 454 */ 455 static void node_hugetlb_work(struct work_struct *work) 456 { 457 struct node *node = container_of(work, struct node, node_work); 458 459 /* 460 * We only get here when a node transitions to/from memoryless state. 461 * We can detect which transition occurred by examining whether the 462 * node has memory now. hugetlb_register_node() already check this 463 * so we try to register the attributes. If that fails, then the 464 * node has transitioned to memoryless, try to unregister the 465 * attributes. 466 */ 467 if (!hugetlb_register_node(node)) 468 hugetlb_unregister_node(node); 469 } 470 471 static void init_node_hugetlb_work(int nid) 472 { 473 INIT_WORK(&node_devices[nid].node_work, node_hugetlb_work); 474 } 475 476 static int node_memory_callback(struct notifier_block *self, 477 unsigned long action, void *arg) 478 { 479 struct memory_notify *mnb = arg; 480 int nid = mnb->status_change_nid; 481 482 switch (action) { 483 case MEM_ONLINE: 484 case MEM_OFFLINE: 485 /* 486 * offload per node hstate [un]registration to a work thread 487 * when transitioning to/from memoryless state. 488 */ 489 if (nid != NUMA_NO_NODE) 490 schedule_work(&node_devices[nid].node_work); 491 break; 492 493 case MEM_GOING_ONLINE: 494 case MEM_GOING_OFFLINE: 495 case MEM_CANCEL_ONLINE: 496 case MEM_CANCEL_OFFLINE: 497 default: 498 break; 499 } 500 501 return NOTIFY_OK; 502 } 503 #endif /* CONFIG_HUGETLBFS */ 504 #else /* !CONFIG_MEMORY_HOTPLUG_SPARSE */ 505 506 static int link_mem_sections(int nid) { return 0; } 507 #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */ 508 509 #if !defined(CONFIG_MEMORY_HOTPLUG_SPARSE) || \ 510 !defined(CONFIG_HUGETLBFS) 511 static inline int node_memory_callback(struct notifier_block *self, 512 unsigned long action, void *arg) 513 { 514 return NOTIFY_OK; 515 } 516 517 static void init_node_hugetlb_work(int nid) { } 518 519 #endif 520 521 int register_one_node(int nid) 522 { 523 int error = 0; 524 int cpu; 525 526 if (node_online(nid)) { 527 int p_node = parent_node(nid); 528 struct node *parent = NULL; 529 530 if (p_node != nid) 531 parent = &node_devices[p_node]; 532 533 error = register_node(&node_devices[nid], nid, parent); 534 535 /* link cpu under this node */ 536 for_each_present_cpu(cpu) { 537 if (cpu_to_node(cpu) == nid) 538 register_cpu_under_node(cpu, nid); 539 } 540 541 /* link memory sections under this node */ 542 error = link_mem_sections(nid); 543 544 /* initialize work queue for memory hot plug */ 545 init_node_hugetlb_work(nid); 546 } 547 548 return error; 549 550 } 551 552 void unregister_one_node(int nid) 553 { 554 unregister_node(&node_devices[nid]); 555 } 556 557 /* 558 * node states attributes 559 */ 560 561 static ssize_t print_nodes_state(enum node_states state, char *buf) 562 { 563 int n; 564 565 n = nodelist_scnprintf(buf, PAGE_SIZE, node_states[state]); 566 if (n > 0 && PAGE_SIZE > n + 1) { 567 *(buf + n++) = '\n'; 568 *(buf + n++) = '\0'; 569 } 570 return n; 571 } 572 573 struct node_attr { 574 struct sysdev_class_attribute attr; 575 enum node_states state; 576 }; 577 578 static ssize_t show_node_state(struct sysdev_class *class, 579 struct sysdev_class_attribute *attr, char *buf) 580 { 581 struct node_attr *na = container_of(attr, struct node_attr, attr); 582 return print_nodes_state(na->state, buf); 583 } 584 585 #define _NODE_ATTR(name, state) \ 586 { _SYSDEV_CLASS_ATTR(name, 0444, show_node_state, NULL), state } 587 588 static struct node_attr node_state_attr[] = { 589 _NODE_ATTR(possible, N_POSSIBLE), 590 _NODE_ATTR(online, N_ONLINE), 591 _NODE_ATTR(has_normal_memory, N_NORMAL_MEMORY), 592 _NODE_ATTR(has_cpu, N_CPU), 593 #ifdef CONFIG_HIGHMEM 594 _NODE_ATTR(has_high_memory, N_HIGH_MEMORY), 595 #endif 596 }; 597 598 static struct sysdev_class_attribute *node_state_attrs[] = { 599 &node_state_attr[0].attr, 600 &node_state_attr[1].attr, 601 &node_state_attr[2].attr, 602 &node_state_attr[3].attr, 603 #ifdef CONFIG_HIGHMEM 604 &node_state_attr[4].attr, 605 #endif 606 NULL 607 }; 608 609 #define NODE_CALLBACK_PRI 2 /* lower than SLAB */ 610 static int __init register_node_type(void) 611 { 612 int ret; 613 614 BUILD_BUG_ON(ARRAY_SIZE(node_state_attr) != NR_NODE_STATES); 615 BUILD_BUG_ON(ARRAY_SIZE(node_state_attrs)-1 != NR_NODE_STATES); 616 617 ret = sysdev_class_register(&node_class); 618 if (!ret) { 619 hotplug_memory_notifier(node_memory_callback, 620 NODE_CALLBACK_PRI); 621 } 622 623 /* 624 * Note: we're not going to unregister the node class if we fail 625 * to register the node state class attribute files. 626 */ 627 return ret; 628 } 629 postcore_initcall(register_node_type); 630