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