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_distance(struct sys_device * dev, 164 struct sysdev_attribute *attr, char * buf) 165 { 166 int nid = dev->id; 167 int len = 0; 168 int i; 169 170 /* 171 * buf is currently PAGE_SIZE in length and each node needs 4 chars 172 * at the most (distance + space or newline). 173 */ 174 BUILD_BUG_ON(MAX_NUMNODES * 4 > PAGE_SIZE); 175 176 for_each_online_node(i) 177 len += sprintf(buf + len, "%s%d", i ? " " : "", node_distance(nid, i)); 178 179 len += sprintf(buf + len, "\n"); 180 return len; 181 } 182 static SYSDEV_ATTR(distance, S_IRUGO, node_read_distance, NULL); 183 184 #ifdef CONFIG_HUGETLBFS 185 /* 186 * hugetlbfs per node attributes registration interface: 187 * When/if hugetlb[fs] subsystem initializes [sometime after this module], 188 * it will register its per node attributes for all online nodes with 189 * memory. It will also call register_hugetlbfs_with_node(), below, to 190 * register its attribute registration functions with this node driver. 191 * Once these hooks have been initialized, the node driver will call into 192 * the hugetlb module to [un]register attributes for hot-plugged nodes. 193 */ 194 static node_registration_func_t __hugetlb_register_node; 195 static node_registration_func_t __hugetlb_unregister_node; 196 197 static inline bool hugetlb_register_node(struct node *node) 198 { 199 if (__hugetlb_register_node && 200 node_state(node->sysdev.id, N_HIGH_MEMORY)) { 201 __hugetlb_register_node(node); 202 return true; 203 } 204 return false; 205 } 206 207 static inline void hugetlb_unregister_node(struct node *node) 208 { 209 if (__hugetlb_unregister_node) 210 __hugetlb_unregister_node(node); 211 } 212 213 void register_hugetlbfs_with_node(node_registration_func_t doregister, 214 node_registration_func_t unregister) 215 { 216 __hugetlb_register_node = doregister; 217 __hugetlb_unregister_node = unregister; 218 } 219 #else 220 static inline void hugetlb_register_node(struct node *node) {} 221 222 static inline void hugetlb_unregister_node(struct node *node) {} 223 #endif 224 225 226 /* 227 * register_node - Setup a sysfs device for a node. 228 * @num - Node number to use when creating the device. 229 * 230 * Initialize and register the node device. 231 */ 232 int register_node(struct node *node, int num, struct node *parent) 233 { 234 int error; 235 236 node->sysdev.id = num; 237 node->sysdev.cls = &node_class; 238 error = sysdev_register(&node->sysdev); 239 240 if (!error){ 241 sysdev_create_file(&node->sysdev, &attr_cpumap); 242 sysdev_create_file(&node->sysdev, &attr_cpulist); 243 sysdev_create_file(&node->sysdev, &attr_meminfo); 244 sysdev_create_file(&node->sysdev, &attr_numastat); 245 sysdev_create_file(&node->sysdev, &attr_distance); 246 247 scan_unevictable_register_node(node); 248 249 hugetlb_register_node(node); 250 251 compaction_register_node(node); 252 } 253 return error; 254 } 255 256 /** 257 * unregister_node - unregister a node device 258 * @node: node going away 259 * 260 * Unregisters a node device @node. All the devices on the node must be 261 * unregistered before calling this function. 262 */ 263 void unregister_node(struct node *node) 264 { 265 sysdev_remove_file(&node->sysdev, &attr_cpumap); 266 sysdev_remove_file(&node->sysdev, &attr_cpulist); 267 sysdev_remove_file(&node->sysdev, &attr_meminfo); 268 sysdev_remove_file(&node->sysdev, &attr_numastat); 269 sysdev_remove_file(&node->sysdev, &attr_distance); 270 271 scan_unevictable_unregister_node(node); 272 hugetlb_unregister_node(node); /* no-op, if memoryless node */ 273 274 sysdev_unregister(&node->sysdev); 275 } 276 277 struct node node_devices[MAX_NUMNODES]; 278 279 /* 280 * register cpu under node 281 */ 282 int register_cpu_under_node(unsigned int cpu, unsigned int nid) 283 { 284 int ret; 285 struct sys_device *obj; 286 287 if (!node_online(nid)) 288 return 0; 289 290 obj = get_cpu_sysdev(cpu); 291 if (!obj) 292 return 0; 293 294 ret = sysfs_create_link(&node_devices[nid].sysdev.kobj, 295 &obj->kobj, 296 kobject_name(&obj->kobj)); 297 if (ret) 298 return ret; 299 300 return sysfs_create_link(&obj->kobj, 301 &node_devices[nid].sysdev.kobj, 302 kobject_name(&node_devices[nid].sysdev.kobj)); 303 } 304 305 int unregister_cpu_under_node(unsigned int cpu, unsigned int nid) 306 { 307 struct sys_device *obj; 308 309 if (!node_online(nid)) 310 return 0; 311 312 obj = get_cpu_sysdev(cpu); 313 if (!obj) 314 return 0; 315 316 sysfs_remove_link(&node_devices[nid].sysdev.kobj, 317 kobject_name(&obj->kobj)); 318 sysfs_remove_link(&obj->kobj, 319 kobject_name(&node_devices[nid].sysdev.kobj)); 320 321 return 0; 322 } 323 324 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE 325 #define page_initialized(page) (page->lru.next) 326 327 static int get_nid_for_pfn(unsigned long pfn) 328 { 329 struct page *page; 330 331 if (!pfn_valid_within(pfn)) 332 return -1; 333 page = pfn_to_page(pfn); 334 if (!page_initialized(page)) 335 return -1; 336 return pfn_to_nid(pfn); 337 } 338 339 /* register memory section under specified node if it spans that node */ 340 int register_mem_sect_under_node(struct memory_block *mem_blk, int nid) 341 { 342 int ret; 343 unsigned long pfn, sect_start_pfn, sect_end_pfn; 344 345 if (!mem_blk) 346 return -EFAULT; 347 if (!node_online(nid)) 348 return 0; 349 sect_start_pfn = section_nr_to_pfn(mem_blk->phys_index); 350 sect_end_pfn = sect_start_pfn + PAGES_PER_SECTION - 1; 351 for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) { 352 int page_nid; 353 354 page_nid = get_nid_for_pfn(pfn); 355 if (page_nid < 0) 356 continue; 357 if (page_nid != nid) 358 continue; 359 ret = sysfs_create_link_nowarn(&node_devices[nid].sysdev.kobj, 360 &mem_blk->sysdev.kobj, 361 kobject_name(&mem_blk->sysdev.kobj)); 362 if (ret) 363 return ret; 364 365 return sysfs_create_link_nowarn(&mem_blk->sysdev.kobj, 366 &node_devices[nid].sysdev.kobj, 367 kobject_name(&node_devices[nid].sysdev.kobj)); 368 } 369 /* mem section does not span the specified node */ 370 return 0; 371 } 372 373 /* unregister memory section under all nodes that it spans */ 374 int unregister_mem_sect_under_nodes(struct memory_block *mem_blk) 375 { 376 NODEMASK_ALLOC(nodemask_t, unlinked_nodes, GFP_KERNEL); 377 unsigned long pfn, sect_start_pfn, sect_end_pfn; 378 379 if (!mem_blk) { 380 NODEMASK_FREE(unlinked_nodes); 381 return -EFAULT; 382 } 383 if (!unlinked_nodes) 384 return -ENOMEM; 385 nodes_clear(*unlinked_nodes); 386 sect_start_pfn = section_nr_to_pfn(mem_blk->phys_index); 387 sect_end_pfn = sect_start_pfn + PAGES_PER_SECTION - 1; 388 for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) { 389 int nid; 390 391 nid = get_nid_for_pfn(pfn); 392 if (nid < 0) 393 continue; 394 if (!node_online(nid)) 395 continue; 396 if (node_test_and_set(nid, *unlinked_nodes)) 397 continue; 398 sysfs_remove_link(&node_devices[nid].sysdev.kobj, 399 kobject_name(&mem_blk->sysdev.kobj)); 400 sysfs_remove_link(&mem_blk->sysdev.kobj, 401 kobject_name(&node_devices[nid].sysdev.kobj)); 402 } 403 NODEMASK_FREE(unlinked_nodes); 404 return 0; 405 } 406 407 static int link_mem_sections(int nid) 408 { 409 unsigned long start_pfn = NODE_DATA(nid)->node_start_pfn; 410 unsigned long end_pfn = start_pfn + NODE_DATA(nid)->node_spanned_pages; 411 unsigned long pfn; 412 struct memory_block *mem_blk = NULL; 413 int err = 0; 414 415 for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) { 416 unsigned long section_nr = pfn_to_section_nr(pfn); 417 struct mem_section *mem_sect; 418 int ret; 419 420 if (!present_section_nr(section_nr)) 421 continue; 422 mem_sect = __nr_to_section(section_nr); 423 mem_blk = find_memory_block_hinted(mem_sect, mem_blk); 424 ret = register_mem_sect_under_node(mem_blk, nid); 425 if (!err) 426 err = ret; 427 428 /* discard ref obtained in find_memory_block() */ 429 } 430 431 if (mem_blk) 432 kobject_put(&mem_blk->sysdev.kobj); 433 return err; 434 } 435 436 #ifdef CONFIG_HUGETLBFS 437 /* 438 * Handle per node hstate attribute [un]registration on transistions 439 * to/from memoryless state. 440 */ 441 static void node_hugetlb_work(struct work_struct *work) 442 { 443 struct node *node = container_of(work, struct node, node_work); 444 445 /* 446 * We only get here when a node transitions to/from memoryless state. 447 * We can detect which transition occurred by examining whether the 448 * node has memory now. hugetlb_register_node() already check this 449 * so we try to register the attributes. If that fails, then the 450 * node has transitioned to memoryless, try to unregister the 451 * attributes. 452 */ 453 if (!hugetlb_register_node(node)) 454 hugetlb_unregister_node(node); 455 } 456 457 static void init_node_hugetlb_work(int nid) 458 { 459 INIT_WORK(&node_devices[nid].node_work, node_hugetlb_work); 460 } 461 462 static int node_memory_callback(struct notifier_block *self, 463 unsigned long action, void *arg) 464 { 465 struct memory_notify *mnb = arg; 466 int nid = mnb->status_change_nid; 467 468 switch (action) { 469 case MEM_ONLINE: 470 case MEM_OFFLINE: 471 /* 472 * offload per node hstate [un]registration to a work thread 473 * when transitioning to/from memoryless state. 474 */ 475 if (nid != NUMA_NO_NODE) 476 schedule_work(&node_devices[nid].node_work); 477 break; 478 479 case MEM_GOING_ONLINE: 480 case MEM_GOING_OFFLINE: 481 case MEM_CANCEL_ONLINE: 482 case MEM_CANCEL_OFFLINE: 483 default: 484 break; 485 } 486 487 return NOTIFY_OK; 488 } 489 #endif /* CONFIG_HUGETLBFS */ 490 #else /* !CONFIG_MEMORY_HOTPLUG_SPARSE */ 491 492 static int link_mem_sections(int nid) { return 0; } 493 #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */ 494 495 #if !defined(CONFIG_MEMORY_HOTPLUG_SPARSE) || \ 496 !defined(CONFIG_HUGETLBFS) 497 static inline int node_memory_callback(struct notifier_block *self, 498 unsigned long action, void *arg) 499 { 500 return NOTIFY_OK; 501 } 502 503 static void init_node_hugetlb_work(int nid) { } 504 505 #endif 506 507 int register_one_node(int nid) 508 { 509 int error = 0; 510 int cpu; 511 512 if (node_online(nid)) { 513 int p_node = parent_node(nid); 514 struct node *parent = NULL; 515 516 if (p_node != nid) 517 parent = &node_devices[p_node]; 518 519 error = register_node(&node_devices[nid], nid, parent); 520 521 /* link cpu under this node */ 522 for_each_present_cpu(cpu) { 523 if (cpu_to_node(cpu) == nid) 524 register_cpu_under_node(cpu, nid); 525 } 526 527 /* link memory sections under this node */ 528 error = link_mem_sections(nid); 529 530 /* initialize work queue for memory hot plug */ 531 init_node_hugetlb_work(nid); 532 } 533 534 return error; 535 536 } 537 538 void unregister_one_node(int nid) 539 { 540 unregister_node(&node_devices[nid]); 541 } 542 543 /* 544 * node states attributes 545 */ 546 547 static ssize_t print_nodes_state(enum node_states state, char *buf) 548 { 549 int n; 550 551 n = nodelist_scnprintf(buf, PAGE_SIZE, node_states[state]); 552 if (n > 0 && PAGE_SIZE > n + 1) { 553 *(buf + n++) = '\n'; 554 *(buf + n++) = '\0'; 555 } 556 return n; 557 } 558 559 struct node_attr { 560 struct sysdev_class_attribute attr; 561 enum node_states state; 562 }; 563 564 static ssize_t show_node_state(struct sysdev_class *class, 565 struct sysdev_class_attribute *attr, char *buf) 566 { 567 struct node_attr *na = container_of(attr, struct node_attr, attr); 568 return print_nodes_state(na->state, buf); 569 } 570 571 #define _NODE_ATTR(name, state) \ 572 { _SYSDEV_CLASS_ATTR(name, 0444, show_node_state, NULL), state } 573 574 static struct node_attr node_state_attr[] = { 575 _NODE_ATTR(possible, N_POSSIBLE), 576 _NODE_ATTR(online, N_ONLINE), 577 _NODE_ATTR(has_normal_memory, N_NORMAL_MEMORY), 578 _NODE_ATTR(has_cpu, N_CPU), 579 #ifdef CONFIG_HIGHMEM 580 _NODE_ATTR(has_high_memory, N_HIGH_MEMORY), 581 #endif 582 }; 583 584 static struct sysdev_class_attribute *node_state_attrs[] = { 585 &node_state_attr[0].attr, 586 &node_state_attr[1].attr, 587 &node_state_attr[2].attr, 588 &node_state_attr[3].attr, 589 #ifdef CONFIG_HIGHMEM 590 &node_state_attr[4].attr, 591 #endif 592 NULL 593 }; 594 595 #define NODE_CALLBACK_PRI 2 /* lower than SLAB */ 596 static int __init register_node_type(void) 597 { 598 int ret; 599 600 BUILD_BUG_ON(ARRAY_SIZE(node_state_attr) != NR_NODE_STATES); 601 BUILD_BUG_ON(ARRAY_SIZE(node_state_attrs)-1 != NR_NODE_STATES); 602 603 ret = sysdev_class_register(&node_class); 604 if (!ret) { 605 hotplug_memory_notifier(node_memory_callback, 606 NODE_CALLBACK_PRI); 607 } 608 609 /* 610 * Note: we're not going to unregister the node class if we fail 611 * to register the node state class attribute files. 612 */ 613 return ret; 614 } 615 postcore_initcall(register_node_type); 616