1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Basic Node interface support 4 */ 5 6 #include <linux/module.h> 7 #include <linux/init.h> 8 #include <linux/mm.h> 9 #include <linux/memory.h> 10 #include <linux/vmstat.h> 11 #include <linux/notifier.h> 12 #include <linux/node.h> 13 #include <linux/hugetlb.h> 14 #include <linux/compaction.h> 15 #include <linux/cpumask.h> 16 #include <linux/topology.h> 17 #include <linux/nodemask.h> 18 #include <linux/cpu.h> 19 #include <linux/device.h> 20 #include <linux/pm_runtime.h> 21 #include <linux/swap.h> 22 #include <linux/slab.h> 23 24 static struct bus_type node_subsys = { 25 .name = "node", 26 .dev_name = "node", 27 }; 28 29 30 static ssize_t node_read_cpumap(struct device *dev, bool list, char *buf) 31 { 32 ssize_t n; 33 cpumask_var_t mask; 34 struct node *node_dev = to_node(dev); 35 36 /* 2008/04/07: buf currently PAGE_SIZE, need 9 chars per 32 bits. */ 37 BUILD_BUG_ON((NR_CPUS/32 * 9) > (PAGE_SIZE-1)); 38 39 if (!alloc_cpumask_var(&mask, GFP_KERNEL)) 40 return 0; 41 42 cpumask_and(mask, cpumask_of_node(node_dev->dev.id), cpu_online_mask); 43 n = cpumap_print_to_pagebuf(list, buf, mask); 44 free_cpumask_var(mask); 45 46 return n; 47 } 48 49 static inline ssize_t node_read_cpumask(struct device *dev, 50 struct device_attribute *attr, char *buf) 51 { 52 return node_read_cpumap(dev, false, buf); 53 } 54 static inline ssize_t node_read_cpulist(struct device *dev, 55 struct device_attribute *attr, char *buf) 56 { 57 return node_read_cpumap(dev, true, buf); 58 } 59 60 static DEVICE_ATTR(cpumap, S_IRUGO, node_read_cpumask, NULL); 61 static DEVICE_ATTR(cpulist, S_IRUGO, node_read_cpulist, NULL); 62 63 /** 64 * struct node_access_nodes - Access class device to hold user visible 65 * relationships to other nodes. 66 * @dev: Device for this memory access class 67 * @list_node: List element in the node's access list 68 * @access: The access class rank 69 * @hmem_attrs: Heterogeneous memory performance attributes 70 */ 71 struct node_access_nodes { 72 struct device dev; 73 struct list_head list_node; 74 unsigned access; 75 #ifdef CONFIG_HMEM_REPORTING 76 struct node_hmem_attrs hmem_attrs; 77 #endif 78 }; 79 #define to_access_nodes(dev) container_of(dev, struct node_access_nodes, dev) 80 81 static struct attribute *node_init_access_node_attrs[] = { 82 NULL, 83 }; 84 85 static struct attribute *node_targ_access_node_attrs[] = { 86 NULL, 87 }; 88 89 static const struct attribute_group initiators = { 90 .name = "initiators", 91 .attrs = node_init_access_node_attrs, 92 }; 93 94 static const struct attribute_group targets = { 95 .name = "targets", 96 .attrs = node_targ_access_node_attrs, 97 }; 98 99 static const struct attribute_group *node_access_node_groups[] = { 100 &initiators, 101 &targets, 102 NULL, 103 }; 104 105 static void node_remove_accesses(struct node *node) 106 { 107 struct node_access_nodes *c, *cnext; 108 109 list_for_each_entry_safe(c, cnext, &node->access_list, list_node) { 110 list_del(&c->list_node); 111 device_unregister(&c->dev); 112 } 113 } 114 115 static void node_access_release(struct device *dev) 116 { 117 kfree(to_access_nodes(dev)); 118 } 119 120 static struct node_access_nodes *node_init_node_access(struct node *node, 121 unsigned access) 122 { 123 struct node_access_nodes *access_node; 124 struct device *dev; 125 126 list_for_each_entry(access_node, &node->access_list, list_node) 127 if (access_node->access == access) 128 return access_node; 129 130 access_node = kzalloc(sizeof(*access_node), GFP_KERNEL); 131 if (!access_node) 132 return NULL; 133 134 access_node->access = access; 135 dev = &access_node->dev; 136 dev->parent = &node->dev; 137 dev->release = node_access_release; 138 dev->groups = node_access_node_groups; 139 if (dev_set_name(dev, "access%u", access)) 140 goto free; 141 142 if (device_register(dev)) 143 goto free_name; 144 145 pm_runtime_no_callbacks(dev); 146 list_add_tail(&access_node->list_node, &node->access_list); 147 return access_node; 148 free_name: 149 kfree_const(dev->kobj.name); 150 free: 151 kfree(access_node); 152 return NULL; 153 } 154 155 #ifdef CONFIG_HMEM_REPORTING 156 #define ACCESS_ATTR(name) \ 157 static ssize_t name##_show(struct device *dev, \ 158 struct device_attribute *attr, \ 159 char *buf) \ 160 { \ 161 return sprintf(buf, "%u\n", to_access_nodes(dev)->hmem_attrs.name); \ 162 } \ 163 static DEVICE_ATTR_RO(name); 164 165 ACCESS_ATTR(read_bandwidth) 166 ACCESS_ATTR(read_latency) 167 ACCESS_ATTR(write_bandwidth) 168 ACCESS_ATTR(write_latency) 169 170 static struct attribute *access_attrs[] = { 171 &dev_attr_read_bandwidth.attr, 172 &dev_attr_read_latency.attr, 173 &dev_attr_write_bandwidth.attr, 174 &dev_attr_write_latency.attr, 175 NULL, 176 }; 177 178 /** 179 * node_set_perf_attrs - Set the performance values for given access class 180 * @nid: Node identifier to be set 181 * @hmem_attrs: Heterogeneous memory performance attributes 182 * @access: The access class the for the given attributes 183 */ 184 void node_set_perf_attrs(unsigned int nid, struct node_hmem_attrs *hmem_attrs, 185 unsigned access) 186 { 187 struct node_access_nodes *c; 188 struct node *node; 189 int i; 190 191 if (WARN_ON_ONCE(!node_online(nid))) 192 return; 193 194 node = node_devices[nid]; 195 c = node_init_node_access(node, access); 196 if (!c) 197 return; 198 199 c->hmem_attrs = *hmem_attrs; 200 for (i = 0; access_attrs[i] != NULL; i++) { 201 if (sysfs_add_file_to_group(&c->dev.kobj, access_attrs[i], 202 "initiators")) { 203 pr_info("failed to add performance attribute to node %d\n", 204 nid); 205 break; 206 } 207 } 208 } 209 210 /** 211 * struct node_cache_info - Internal tracking for memory node caches 212 * @dev: Device represeting the cache level 213 * @node: List element for tracking in the node 214 * @cache_attrs:Attributes for this cache level 215 */ 216 struct node_cache_info { 217 struct device dev; 218 struct list_head node; 219 struct node_cache_attrs cache_attrs; 220 }; 221 #define to_cache_info(device) container_of(device, struct node_cache_info, dev) 222 223 #define CACHE_ATTR(name, fmt) \ 224 static ssize_t name##_show(struct device *dev, \ 225 struct device_attribute *attr, \ 226 char *buf) \ 227 { \ 228 return sprintf(buf, fmt "\n", to_cache_info(dev)->cache_attrs.name);\ 229 } \ 230 DEVICE_ATTR_RO(name); 231 232 CACHE_ATTR(size, "%llu") 233 CACHE_ATTR(line_size, "%u") 234 CACHE_ATTR(indexing, "%u") 235 CACHE_ATTR(write_policy, "%u") 236 237 static struct attribute *cache_attrs[] = { 238 &dev_attr_indexing.attr, 239 &dev_attr_size.attr, 240 &dev_attr_line_size.attr, 241 &dev_attr_write_policy.attr, 242 NULL, 243 }; 244 ATTRIBUTE_GROUPS(cache); 245 246 static void node_cache_release(struct device *dev) 247 { 248 kfree(dev); 249 } 250 251 static void node_cacheinfo_release(struct device *dev) 252 { 253 struct node_cache_info *info = to_cache_info(dev); 254 kfree(info); 255 } 256 257 static void node_init_cache_dev(struct node *node) 258 { 259 struct device *dev; 260 261 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 262 if (!dev) 263 return; 264 265 dev->parent = &node->dev; 266 dev->release = node_cache_release; 267 if (dev_set_name(dev, "memory_side_cache")) 268 goto free_dev; 269 270 if (device_register(dev)) 271 goto free_name; 272 273 pm_runtime_no_callbacks(dev); 274 node->cache_dev = dev; 275 return; 276 free_name: 277 kfree_const(dev->kobj.name); 278 free_dev: 279 kfree(dev); 280 } 281 282 /** 283 * node_add_cache() - add cache attribute to a memory node 284 * @nid: Node identifier that has new cache attributes 285 * @cache_attrs: Attributes for the cache being added 286 */ 287 void node_add_cache(unsigned int nid, struct node_cache_attrs *cache_attrs) 288 { 289 struct node_cache_info *info; 290 struct device *dev; 291 struct node *node; 292 293 if (!node_online(nid) || !node_devices[nid]) 294 return; 295 296 node = node_devices[nid]; 297 list_for_each_entry(info, &node->cache_attrs, node) { 298 if (info->cache_attrs.level == cache_attrs->level) { 299 dev_warn(&node->dev, 300 "attempt to add duplicate cache level:%d\n", 301 cache_attrs->level); 302 return; 303 } 304 } 305 306 if (!node->cache_dev) 307 node_init_cache_dev(node); 308 if (!node->cache_dev) 309 return; 310 311 info = kzalloc(sizeof(*info), GFP_KERNEL); 312 if (!info) 313 return; 314 315 dev = &info->dev; 316 dev->parent = node->cache_dev; 317 dev->release = node_cacheinfo_release; 318 dev->groups = cache_groups; 319 if (dev_set_name(dev, "index%d", cache_attrs->level)) 320 goto free_cache; 321 322 info->cache_attrs = *cache_attrs; 323 if (device_register(dev)) { 324 dev_warn(&node->dev, "failed to add cache level:%d\n", 325 cache_attrs->level); 326 goto free_name; 327 } 328 pm_runtime_no_callbacks(dev); 329 list_add_tail(&info->node, &node->cache_attrs); 330 return; 331 free_name: 332 kfree_const(dev->kobj.name); 333 free_cache: 334 kfree(info); 335 } 336 337 static void node_remove_caches(struct node *node) 338 { 339 struct node_cache_info *info, *next; 340 341 if (!node->cache_dev) 342 return; 343 344 list_for_each_entry_safe(info, next, &node->cache_attrs, node) { 345 list_del(&info->node); 346 device_unregister(&info->dev); 347 } 348 device_unregister(node->cache_dev); 349 } 350 351 static void node_init_caches(unsigned int nid) 352 { 353 INIT_LIST_HEAD(&node_devices[nid]->cache_attrs); 354 } 355 #else 356 static void node_init_caches(unsigned int nid) { } 357 static void node_remove_caches(struct node *node) { } 358 #endif 359 360 #define K(x) ((x) << (PAGE_SHIFT - 10)) 361 static ssize_t node_read_meminfo(struct device *dev, 362 struct device_attribute *attr, char *buf) 363 { 364 int n; 365 int nid = dev->id; 366 struct pglist_data *pgdat = NODE_DATA(nid); 367 struct sysinfo i; 368 unsigned long sreclaimable, sunreclaimable; 369 370 si_meminfo_node(&i, nid); 371 sreclaimable = node_page_state_pages(pgdat, NR_SLAB_RECLAIMABLE_B); 372 sunreclaimable = node_page_state_pages(pgdat, NR_SLAB_UNRECLAIMABLE_B); 373 n = sprintf(buf, 374 "Node %d MemTotal: %8lu kB\n" 375 "Node %d MemFree: %8lu kB\n" 376 "Node %d MemUsed: %8lu kB\n" 377 "Node %d Active: %8lu kB\n" 378 "Node %d Inactive: %8lu kB\n" 379 "Node %d Active(anon): %8lu kB\n" 380 "Node %d Inactive(anon): %8lu kB\n" 381 "Node %d Active(file): %8lu kB\n" 382 "Node %d Inactive(file): %8lu kB\n" 383 "Node %d Unevictable: %8lu kB\n" 384 "Node %d Mlocked: %8lu kB\n", 385 nid, K(i.totalram), 386 nid, K(i.freeram), 387 nid, K(i.totalram - i.freeram), 388 nid, K(node_page_state(pgdat, NR_ACTIVE_ANON) + 389 node_page_state(pgdat, NR_ACTIVE_FILE)), 390 nid, K(node_page_state(pgdat, NR_INACTIVE_ANON) + 391 node_page_state(pgdat, NR_INACTIVE_FILE)), 392 nid, K(node_page_state(pgdat, NR_ACTIVE_ANON)), 393 nid, K(node_page_state(pgdat, NR_INACTIVE_ANON)), 394 nid, K(node_page_state(pgdat, NR_ACTIVE_FILE)), 395 nid, K(node_page_state(pgdat, NR_INACTIVE_FILE)), 396 nid, K(node_page_state(pgdat, NR_UNEVICTABLE)), 397 nid, K(sum_zone_node_page_state(nid, NR_MLOCK))); 398 399 #ifdef CONFIG_HIGHMEM 400 n += sprintf(buf + n, 401 "Node %d HighTotal: %8lu kB\n" 402 "Node %d HighFree: %8lu kB\n" 403 "Node %d LowTotal: %8lu kB\n" 404 "Node %d LowFree: %8lu kB\n", 405 nid, K(i.totalhigh), 406 nid, K(i.freehigh), 407 nid, K(i.totalram - i.totalhigh), 408 nid, K(i.freeram - i.freehigh)); 409 #endif 410 n += sprintf(buf + n, 411 "Node %d Dirty: %8lu kB\n" 412 "Node %d Writeback: %8lu kB\n" 413 "Node %d FilePages: %8lu kB\n" 414 "Node %d Mapped: %8lu kB\n" 415 "Node %d AnonPages: %8lu kB\n" 416 "Node %d Shmem: %8lu kB\n" 417 "Node %d KernelStack: %8lu kB\n" 418 #ifdef CONFIG_SHADOW_CALL_STACK 419 "Node %d ShadowCallStack:%8lu kB\n" 420 #endif 421 "Node %d PageTables: %8lu kB\n" 422 "Node %d NFS_Unstable: %8lu kB\n" 423 "Node %d Bounce: %8lu kB\n" 424 "Node %d WritebackTmp: %8lu kB\n" 425 "Node %d KReclaimable: %8lu kB\n" 426 "Node %d Slab: %8lu kB\n" 427 "Node %d SReclaimable: %8lu kB\n" 428 "Node %d SUnreclaim: %8lu kB\n" 429 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 430 "Node %d AnonHugePages: %8lu kB\n" 431 "Node %d ShmemHugePages: %8lu kB\n" 432 "Node %d ShmemPmdMapped: %8lu kB\n" 433 "Node %d FileHugePages: %8lu kB\n" 434 "Node %d FilePmdMapped: %8lu kB\n" 435 #endif 436 , 437 nid, K(node_page_state(pgdat, NR_FILE_DIRTY)), 438 nid, K(node_page_state(pgdat, NR_WRITEBACK)), 439 nid, K(node_page_state(pgdat, NR_FILE_PAGES)), 440 nid, K(node_page_state(pgdat, NR_FILE_MAPPED)), 441 nid, K(node_page_state(pgdat, NR_ANON_MAPPED)), 442 nid, K(i.sharedram), 443 nid, node_page_state(pgdat, NR_KERNEL_STACK_KB), 444 #ifdef CONFIG_SHADOW_CALL_STACK 445 nid, node_page_state(pgdat, NR_KERNEL_SCS_KB), 446 #endif 447 nid, K(sum_zone_node_page_state(nid, NR_PAGETABLE)), 448 nid, 0UL, 449 nid, K(sum_zone_node_page_state(nid, NR_BOUNCE)), 450 nid, K(node_page_state(pgdat, NR_WRITEBACK_TEMP)), 451 nid, K(sreclaimable + 452 node_page_state(pgdat, NR_KERNEL_MISC_RECLAIMABLE)), 453 nid, K(sreclaimable + sunreclaimable), 454 nid, K(sreclaimable), 455 nid, K(sunreclaimable) 456 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 457 , 458 nid, K(node_page_state(pgdat, NR_ANON_THPS) * 459 HPAGE_PMD_NR), 460 nid, K(node_page_state(pgdat, NR_SHMEM_THPS) * 461 HPAGE_PMD_NR), 462 nid, K(node_page_state(pgdat, NR_SHMEM_PMDMAPPED) * 463 HPAGE_PMD_NR), 464 nid, K(node_page_state(pgdat, NR_FILE_THPS) * 465 HPAGE_PMD_NR), 466 nid, K(node_page_state(pgdat, NR_FILE_PMDMAPPED) * 467 HPAGE_PMD_NR) 468 #endif 469 ); 470 n += hugetlb_report_node_meminfo(nid, buf + n); 471 return n; 472 } 473 474 #undef K 475 static DEVICE_ATTR(meminfo, S_IRUGO, node_read_meminfo, NULL); 476 477 static ssize_t node_read_numastat(struct device *dev, 478 struct device_attribute *attr, char *buf) 479 { 480 return sprintf(buf, 481 "numa_hit %lu\n" 482 "numa_miss %lu\n" 483 "numa_foreign %lu\n" 484 "interleave_hit %lu\n" 485 "local_node %lu\n" 486 "other_node %lu\n", 487 sum_zone_numa_state(dev->id, NUMA_HIT), 488 sum_zone_numa_state(dev->id, NUMA_MISS), 489 sum_zone_numa_state(dev->id, NUMA_FOREIGN), 490 sum_zone_numa_state(dev->id, NUMA_INTERLEAVE_HIT), 491 sum_zone_numa_state(dev->id, NUMA_LOCAL), 492 sum_zone_numa_state(dev->id, NUMA_OTHER)); 493 } 494 static DEVICE_ATTR(numastat, S_IRUGO, node_read_numastat, NULL); 495 496 static ssize_t node_read_vmstat(struct device *dev, 497 struct device_attribute *attr, char *buf) 498 { 499 int nid = dev->id; 500 struct pglist_data *pgdat = NODE_DATA(nid); 501 int i; 502 int n = 0; 503 504 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) 505 n += sprintf(buf+n, "%s %lu\n", zone_stat_name(i), 506 sum_zone_node_page_state(nid, i)); 507 508 #ifdef CONFIG_NUMA 509 for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++) 510 n += sprintf(buf+n, "%s %lu\n", numa_stat_name(i), 511 sum_zone_numa_state(nid, i)); 512 #endif 513 514 for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) 515 n += sprintf(buf+n, "%s %lu\n", node_stat_name(i), 516 node_page_state_pages(pgdat, i)); 517 518 return n; 519 } 520 static DEVICE_ATTR(vmstat, S_IRUGO, node_read_vmstat, NULL); 521 522 static ssize_t node_read_distance(struct device *dev, 523 struct device_attribute *attr, char *buf) 524 { 525 int nid = dev->id; 526 int len = 0; 527 int i; 528 529 /* 530 * buf is currently PAGE_SIZE in length and each node needs 4 chars 531 * at the most (distance + space or newline). 532 */ 533 BUILD_BUG_ON(MAX_NUMNODES * 4 > PAGE_SIZE); 534 535 for_each_online_node(i) 536 len += sprintf(buf + len, "%s%d", i ? " " : "", node_distance(nid, i)); 537 538 len += sprintf(buf + len, "\n"); 539 return len; 540 } 541 static DEVICE_ATTR(distance, S_IRUGO, node_read_distance, NULL); 542 543 static struct attribute *node_dev_attrs[] = { 544 &dev_attr_cpumap.attr, 545 &dev_attr_cpulist.attr, 546 &dev_attr_meminfo.attr, 547 &dev_attr_numastat.attr, 548 &dev_attr_distance.attr, 549 &dev_attr_vmstat.attr, 550 NULL 551 }; 552 ATTRIBUTE_GROUPS(node_dev); 553 554 #ifdef CONFIG_HUGETLBFS 555 /* 556 * hugetlbfs per node attributes registration interface: 557 * When/if hugetlb[fs] subsystem initializes [sometime after this module], 558 * it will register its per node attributes for all online nodes with 559 * memory. It will also call register_hugetlbfs_with_node(), below, to 560 * register its attribute registration functions with this node driver. 561 * Once these hooks have been initialized, the node driver will call into 562 * the hugetlb module to [un]register attributes for hot-plugged nodes. 563 */ 564 static node_registration_func_t __hugetlb_register_node; 565 static node_registration_func_t __hugetlb_unregister_node; 566 567 static inline bool hugetlb_register_node(struct node *node) 568 { 569 if (__hugetlb_register_node && 570 node_state(node->dev.id, N_MEMORY)) { 571 __hugetlb_register_node(node); 572 return true; 573 } 574 return false; 575 } 576 577 static inline void hugetlb_unregister_node(struct node *node) 578 { 579 if (__hugetlb_unregister_node) 580 __hugetlb_unregister_node(node); 581 } 582 583 void register_hugetlbfs_with_node(node_registration_func_t doregister, 584 node_registration_func_t unregister) 585 { 586 __hugetlb_register_node = doregister; 587 __hugetlb_unregister_node = unregister; 588 } 589 #else 590 static inline void hugetlb_register_node(struct node *node) {} 591 592 static inline void hugetlb_unregister_node(struct node *node) {} 593 #endif 594 595 static void node_device_release(struct device *dev) 596 { 597 struct node *node = to_node(dev); 598 599 #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HUGETLBFS) 600 /* 601 * We schedule the work only when a memory section is 602 * onlined/offlined on this node. When we come here, 603 * all the memory on this node has been offlined, 604 * so we won't enqueue new work to this work. 605 * 606 * The work is using node->node_work, so we should 607 * flush work before freeing the memory. 608 */ 609 flush_work(&node->node_work); 610 #endif 611 kfree(node); 612 } 613 614 /* 615 * register_node - Setup a sysfs device for a node. 616 * @num - Node number to use when creating the device. 617 * 618 * Initialize and register the node device. 619 */ 620 static int register_node(struct node *node, int num) 621 { 622 int error; 623 624 node->dev.id = num; 625 node->dev.bus = &node_subsys; 626 node->dev.release = node_device_release; 627 node->dev.groups = node_dev_groups; 628 error = device_register(&node->dev); 629 630 if (error) 631 put_device(&node->dev); 632 else { 633 hugetlb_register_node(node); 634 635 compaction_register_node(node); 636 } 637 return error; 638 } 639 640 /** 641 * unregister_node - unregister a node device 642 * @node: node going away 643 * 644 * Unregisters a node device @node. All the devices on the node must be 645 * unregistered before calling this function. 646 */ 647 void unregister_node(struct node *node) 648 { 649 hugetlb_unregister_node(node); /* no-op, if memoryless node */ 650 node_remove_accesses(node); 651 node_remove_caches(node); 652 device_unregister(&node->dev); 653 } 654 655 struct node *node_devices[MAX_NUMNODES]; 656 657 /* 658 * register cpu under node 659 */ 660 int register_cpu_under_node(unsigned int cpu, unsigned int nid) 661 { 662 int ret; 663 struct device *obj; 664 665 if (!node_online(nid)) 666 return 0; 667 668 obj = get_cpu_device(cpu); 669 if (!obj) 670 return 0; 671 672 ret = sysfs_create_link(&node_devices[nid]->dev.kobj, 673 &obj->kobj, 674 kobject_name(&obj->kobj)); 675 if (ret) 676 return ret; 677 678 return sysfs_create_link(&obj->kobj, 679 &node_devices[nid]->dev.kobj, 680 kobject_name(&node_devices[nid]->dev.kobj)); 681 } 682 683 /** 684 * register_memory_node_under_compute_node - link memory node to its compute 685 * node for a given access class. 686 * @mem_nid: Memory node number 687 * @cpu_nid: Cpu node number 688 * @access: Access class to register 689 * 690 * Description: 691 * For use with platforms that may have separate memory and compute nodes. 692 * This function will export node relationships linking which memory 693 * initiator nodes can access memory targets at a given ranked access 694 * class. 695 */ 696 int register_memory_node_under_compute_node(unsigned int mem_nid, 697 unsigned int cpu_nid, 698 unsigned access) 699 { 700 struct node *init_node, *targ_node; 701 struct node_access_nodes *initiator, *target; 702 int ret; 703 704 if (!node_online(cpu_nid) || !node_online(mem_nid)) 705 return -ENODEV; 706 707 init_node = node_devices[cpu_nid]; 708 targ_node = node_devices[mem_nid]; 709 initiator = node_init_node_access(init_node, access); 710 target = node_init_node_access(targ_node, access); 711 if (!initiator || !target) 712 return -ENOMEM; 713 714 ret = sysfs_add_link_to_group(&initiator->dev.kobj, "targets", 715 &targ_node->dev.kobj, 716 dev_name(&targ_node->dev)); 717 if (ret) 718 return ret; 719 720 ret = sysfs_add_link_to_group(&target->dev.kobj, "initiators", 721 &init_node->dev.kobj, 722 dev_name(&init_node->dev)); 723 if (ret) 724 goto err; 725 726 return 0; 727 err: 728 sysfs_remove_link_from_group(&initiator->dev.kobj, "targets", 729 dev_name(&targ_node->dev)); 730 return ret; 731 } 732 733 int unregister_cpu_under_node(unsigned int cpu, unsigned int nid) 734 { 735 struct device *obj; 736 737 if (!node_online(nid)) 738 return 0; 739 740 obj = get_cpu_device(cpu); 741 if (!obj) 742 return 0; 743 744 sysfs_remove_link(&node_devices[nid]->dev.kobj, 745 kobject_name(&obj->kobj)); 746 sysfs_remove_link(&obj->kobj, 747 kobject_name(&node_devices[nid]->dev.kobj)); 748 749 return 0; 750 } 751 752 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE 753 static int __ref get_nid_for_pfn(unsigned long pfn) 754 { 755 if (!pfn_valid_within(pfn)) 756 return -1; 757 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT 758 if (system_state < SYSTEM_RUNNING) 759 return early_pfn_to_nid(pfn); 760 #endif 761 return pfn_to_nid(pfn); 762 } 763 764 /* register memory section under specified node if it spans that node */ 765 static int register_mem_sect_under_node(struct memory_block *mem_blk, 766 void *arg) 767 { 768 unsigned long memory_block_pfns = memory_block_size_bytes() / PAGE_SIZE; 769 unsigned long start_pfn = section_nr_to_pfn(mem_blk->start_section_nr); 770 unsigned long end_pfn = start_pfn + memory_block_pfns - 1; 771 int ret, nid = *(int *)arg; 772 unsigned long pfn; 773 774 for (pfn = start_pfn; pfn <= end_pfn; pfn++) { 775 int page_nid; 776 777 /* 778 * memory block could have several absent sections from start. 779 * skip pfn range from absent section 780 */ 781 if (!pfn_in_present_section(pfn)) { 782 pfn = round_down(pfn + PAGES_PER_SECTION, 783 PAGES_PER_SECTION) - 1; 784 continue; 785 } 786 787 /* 788 * We need to check if page belongs to nid only for the boot 789 * case, during hotplug we know that all pages in the memory 790 * block belong to the same node. 791 */ 792 if (system_state == SYSTEM_BOOTING) { 793 page_nid = get_nid_for_pfn(pfn); 794 if (page_nid < 0) 795 continue; 796 if (page_nid != nid) 797 continue; 798 } 799 800 /* 801 * If this memory block spans multiple nodes, we only indicate 802 * the last processed node. 803 */ 804 mem_blk->nid = nid; 805 806 ret = sysfs_create_link_nowarn(&node_devices[nid]->dev.kobj, 807 &mem_blk->dev.kobj, 808 kobject_name(&mem_blk->dev.kobj)); 809 if (ret) 810 return ret; 811 812 return sysfs_create_link_nowarn(&mem_blk->dev.kobj, 813 &node_devices[nid]->dev.kobj, 814 kobject_name(&node_devices[nid]->dev.kobj)); 815 } 816 /* mem section does not span the specified node */ 817 return 0; 818 } 819 820 /* 821 * Unregister a memory block device under the node it spans. Memory blocks 822 * with multiple nodes cannot be offlined and therefore also never be removed. 823 */ 824 void unregister_memory_block_under_nodes(struct memory_block *mem_blk) 825 { 826 if (mem_blk->nid == NUMA_NO_NODE) 827 return; 828 829 sysfs_remove_link(&node_devices[mem_blk->nid]->dev.kobj, 830 kobject_name(&mem_blk->dev.kobj)); 831 sysfs_remove_link(&mem_blk->dev.kobj, 832 kobject_name(&node_devices[mem_blk->nid]->dev.kobj)); 833 } 834 835 int link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn) 836 { 837 return walk_memory_blocks(PFN_PHYS(start_pfn), 838 PFN_PHYS(end_pfn - start_pfn), (void *)&nid, 839 register_mem_sect_under_node); 840 } 841 842 #ifdef CONFIG_HUGETLBFS 843 /* 844 * Handle per node hstate attribute [un]registration on transistions 845 * to/from memoryless state. 846 */ 847 static void node_hugetlb_work(struct work_struct *work) 848 { 849 struct node *node = container_of(work, struct node, node_work); 850 851 /* 852 * We only get here when a node transitions to/from memoryless state. 853 * We can detect which transition occurred by examining whether the 854 * node has memory now. hugetlb_register_node() already check this 855 * so we try to register the attributes. If that fails, then the 856 * node has transitioned to memoryless, try to unregister the 857 * attributes. 858 */ 859 if (!hugetlb_register_node(node)) 860 hugetlb_unregister_node(node); 861 } 862 863 static void init_node_hugetlb_work(int nid) 864 { 865 INIT_WORK(&node_devices[nid]->node_work, node_hugetlb_work); 866 } 867 868 static int node_memory_callback(struct notifier_block *self, 869 unsigned long action, void *arg) 870 { 871 struct memory_notify *mnb = arg; 872 int nid = mnb->status_change_nid; 873 874 switch (action) { 875 case MEM_ONLINE: 876 case MEM_OFFLINE: 877 /* 878 * offload per node hstate [un]registration to a work thread 879 * when transitioning to/from memoryless state. 880 */ 881 if (nid != NUMA_NO_NODE) 882 schedule_work(&node_devices[nid]->node_work); 883 break; 884 885 case MEM_GOING_ONLINE: 886 case MEM_GOING_OFFLINE: 887 case MEM_CANCEL_ONLINE: 888 case MEM_CANCEL_OFFLINE: 889 default: 890 break; 891 } 892 893 return NOTIFY_OK; 894 } 895 #endif /* CONFIG_HUGETLBFS */ 896 #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */ 897 898 #if !defined(CONFIG_MEMORY_HOTPLUG_SPARSE) || \ 899 !defined(CONFIG_HUGETLBFS) 900 static inline int node_memory_callback(struct notifier_block *self, 901 unsigned long action, void *arg) 902 { 903 return NOTIFY_OK; 904 } 905 906 static void init_node_hugetlb_work(int nid) { } 907 908 #endif 909 910 int __register_one_node(int nid) 911 { 912 int error; 913 int cpu; 914 915 node_devices[nid] = kzalloc(sizeof(struct node), GFP_KERNEL); 916 if (!node_devices[nid]) 917 return -ENOMEM; 918 919 error = register_node(node_devices[nid], nid); 920 921 /* link cpu under this node */ 922 for_each_present_cpu(cpu) { 923 if (cpu_to_node(cpu) == nid) 924 register_cpu_under_node(cpu, nid); 925 } 926 927 INIT_LIST_HEAD(&node_devices[nid]->access_list); 928 /* initialize work queue for memory hot plug */ 929 init_node_hugetlb_work(nid); 930 node_init_caches(nid); 931 932 return error; 933 } 934 935 void unregister_one_node(int nid) 936 { 937 if (!node_devices[nid]) 938 return; 939 940 unregister_node(node_devices[nid]); 941 node_devices[nid] = NULL; 942 } 943 944 /* 945 * node states attributes 946 */ 947 948 static ssize_t print_nodes_state(enum node_states state, char *buf) 949 { 950 int n; 951 952 n = scnprintf(buf, PAGE_SIZE - 1, "%*pbl", 953 nodemask_pr_args(&node_states[state])); 954 buf[n++] = '\n'; 955 buf[n] = '\0'; 956 return n; 957 } 958 959 struct node_attr { 960 struct device_attribute attr; 961 enum node_states state; 962 }; 963 964 static ssize_t show_node_state(struct device *dev, 965 struct device_attribute *attr, char *buf) 966 { 967 struct node_attr *na = container_of(attr, struct node_attr, attr); 968 return print_nodes_state(na->state, buf); 969 } 970 971 #define _NODE_ATTR(name, state) \ 972 { __ATTR(name, 0444, show_node_state, NULL), state } 973 974 static struct node_attr node_state_attr[] = { 975 [N_POSSIBLE] = _NODE_ATTR(possible, N_POSSIBLE), 976 [N_ONLINE] = _NODE_ATTR(online, N_ONLINE), 977 [N_NORMAL_MEMORY] = _NODE_ATTR(has_normal_memory, N_NORMAL_MEMORY), 978 #ifdef CONFIG_HIGHMEM 979 [N_HIGH_MEMORY] = _NODE_ATTR(has_high_memory, N_HIGH_MEMORY), 980 #endif 981 [N_MEMORY] = _NODE_ATTR(has_memory, N_MEMORY), 982 [N_CPU] = _NODE_ATTR(has_cpu, N_CPU), 983 }; 984 985 static struct attribute *node_state_attrs[] = { 986 &node_state_attr[N_POSSIBLE].attr.attr, 987 &node_state_attr[N_ONLINE].attr.attr, 988 &node_state_attr[N_NORMAL_MEMORY].attr.attr, 989 #ifdef CONFIG_HIGHMEM 990 &node_state_attr[N_HIGH_MEMORY].attr.attr, 991 #endif 992 &node_state_attr[N_MEMORY].attr.attr, 993 &node_state_attr[N_CPU].attr.attr, 994 NULL 995 }; 996 997 static struct attribute_group memory_root_attr_group = { 998 .attrs = node_state_attrs, 999 }; 1000 1001 static const struct attribute_group *cpu_root_attr_groups[] = { 1002 &memory_root_attr_group, 1003 NULL, 1004 }; 1005 1006 #define NODE_CALLBACK_PRI 2 /* lower than SLAB */ 1007 static int __init register_node_type(void) 1008 { 1009 int ret; 1010 1011 BUILD_BUG_ON(ARRAY_SIZE(node_state_attr) != NR_NODE_STATES); 1012 BUILD_BUG_ON(ARRAY_SIZE(node_state_attrs)-1 != NR_NODE_STATES); 1013 1014 ret = subsys_system_register(&node_subsys, cpu_root_attr_groups); 1015 if (!ret) { 1016 static struct notifier_block node_memory_callback_nb = { 1017 .notifier_call = node_memory_callback, 1018 .priority = NODE_CALLBACK_PRI, 1019 }; 1020 register_hotmemory_notifier(&node_memory_callback_nb); 1021 } 1022 1023 /* 1024 * Note: we're not going to unregister the node class if we fail 1025 * to register the node state class attribute files. 1026 */ 1027 return ret; 1028 } 1029 postcore_initcall(register_node_type); 1030