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