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 cpumap_show(struct device *dev, 50 struct device_attribute *attr, 51 char *buf) 52 { 53 return node_read_cpumap(dev, false, buf); 54 } 55 56 static DEVICE_ATTR_RO(cpumap); 57 58 static inline ssize_t cpulist_show(struct device *dev, 59 struct device_attribute *attr, 60 char *buf) 61 { 62 return node_read_cpumap(dev, true, buf); 63 } 64 65 static DEVICE_ATTR_RO(cpulist); 66 67 /** 68 * struct node_access_nodes - Access class device to hold user visible 69 * relationships to other nodes. 70 * @dev: Device for this memory access class 71 * @list_node: List element in the node's access list 72 * @access: The access class rank 73 * @hmem_attrs: Heterogeneous memory performance attributes 74 */ 75 struct node_access_nodes { 76 struct device dev; 77 struct list_head list_node; 78 unsigned access; 79 #ifdef CONFIG_HMEM_REPORTING 80 struct node_hmem_attrs hmem_attrs; 81 #endif 82 }; 83 #define to_access_nodes(dev) container_of(dev, struct node_access_nodes, dev) 84 85 static struct attribute *node_init_access_node_attrs[] = { 86 NULL, 87 }; 88 89 static struct attribute *node_targ_access_node_attrs[] = { 90 NULL, 91 }; 92 93 static const struct attribute_group initiators = { 94 .name = "initiators", 95 .attrs = node_init_access_node_attrs, 96 }; 97 98 static const struct attribute_group targets = { 99 .name = "targets", 100 .attrs = node_targ_access_node_attrs, 101 }; 102 103 static const struct attribute_group *node_access_node_groups[] = { 104 &initiators, 105 &targets, 106 NULL, 107 }; 108 109 static void node_remove_accesses(struct node *node) 110 { 111 struct node_access_nodes *c, *cnext; 112 113 list_for_each_entry_safe(c, cnext, &node->access_list, list_node) { 114 list_del(&c->list_node); 115 device_unregister(&c->dev); 116 } 117 } 118 119 static void node_access_release(struct device *dev) 120 { 121 kfree(to_access_nodes(dev)); 122 } 123 124 static struct node_access_nodes *node_init_node_access(struct node *node, 125 unsigned access) 126 { 127 struct node_access_nodes *access_node; 128 struct device *dev; 129 130 list_for_each_entry(access_node, &node->access_list, list_node) 131 if (access_node->access == access) 132 return access_node; 133 134 access_node = kzalloc(sizeof(*access_node), GFP_KERNEL); 135 if (!access_node) 136 return NULL; 137 138 access_node->access = access; 139 dev = &access_node->dev; 140 dev->parent = &node->dev; 141 dev->release = node_access_release; 142 dev->groups = node_access_node_groups; 143 if (dev_set_name(dev, "access%u", access)) 144 goto free; 145 146 if (device_register(dev)) 147 goto free_name; 148 149 pm_runtime_no_callbacks(dev); 150 list_add_tail(&access_node->list_node, &node->access_list); 151 return access_node; 152 free_name: 153 kfree_const(dev->kobj.name); 154 free: 155 kfree(access_node); 156 return NULL; 157 } 158 159 #ifdef CONFIG_HMEM_REPORTING 160 #define ACCESS_ATTR(name) \ 161 static ssize_t name##_show(struct device *dev, \ 162 struct device_attribute *attr, \ 163 char *buf) \ 164 { \ 165 return sysfs_emit(buf, "%u\n", \ 166 to_access_nodes(dev)->hmem_attrs.name); \ 167 } \ 168 static DEVICE_ATTR_RO(name) 169 170 ACCESS_ATTR(read_bandwidth); 171 ACCESS_ATTR(read_latency); 172 ACCESS_ATTR(write_bandwidth); 173 ACCESS_ATTR(write_latency); 174 175 static struct attribute *access_attrs[] = { 176 &dev_attr_read_bandwidth.attr, 177 &dev_attr_read_latency.attr, 178 &dev_attr_write_bandwidth.attr, 179 &dev_attr_write_latency.attr, 180 NULL, 181 }; 182 183 /** 184 * node_set_perf_attrs - Set the performance values for given access class 185 * @nid: Node identifier to be set 186 * @hmem_attrs: Heterogeneous memory performance attributes 187 * @access: The access class the for the given attributes 188 */ 189 void node_set_perf_attrs(unsigned int nid, struct node_hmem_attrs *hmem_attrs, 190 unsigned access) 191 { 192 struct node_access_nodes *c; 193 struct node *node; 194 int i; 195 196 if (WARN_ON_ONCE(!node_online(nid))) 197 return; 198 199 node = node_devices[nid]; 200 c = node_init_node_access(node, access); 201 if (!c) 202 return; 203 204 c->hmem_attrs = *hmem_attrs; 205 for (i = 0; access_attrs[i] != NULL; i++) { 206 if (sysfs_add_file_to_group(&c->dev.kobj, access_attrs[i], 207 "initiators")) { 208 pr_info("failed to add performance attribute to node %d\n", 209 nid); 210 break; 211 } 212 } 213 } 214 215 /** 216 * struct node_cache_info - Internal tracking for memory node caches 217 * @dev: Device represeting the cache level 218 * @node: List element for tracking in the node 219 * @cache_attrs:Attributes for this cache level 220 */ 221 struct node_cache_info { 222 struct device dev; 223 struct list_head node; 224 struct node_cache_attrs cache_attrs; 225 }; 226 #define to_cache_info(device) container_of(device, struct node_cache_info, dev) 227 228 #define CACHE_ATTR(name, fmt) \ 229 static ssize_t name##_show(struct device *dev, \ 230 struct device_attribute *attr, \ 231 char *buf) \ 232 { \ 233 return sysfs_emit(buf, fmt "\n", \ 234 to_cache_info(dev)->cache_attrs.name); \ 235 } \ 236 static DEVICE_ATTR_RO(name); 237 238 CACHE_ATTR(size, "%llu") 239 CACHE_ATTR(line_size, "%u") 240 CACHE_ATTR(indexing, "%u") 241 CACHE_ATTR(write_policy, "%u") 242 243 static struct attribute *cache_attrs[] = { 244 &dev_attr_indexing.attr, 245 &dev_attr_size.attr, 246 &dev_attr_line_size.attr, 247 &dev_attr_write_policy.attr, 248 NULL, 249 }; 250 ATTRIBUTE_GROUPS(cache); 251 252 static void node_cache_release(struct device *dev) 253 { 254 kfree(dev); 255 } 256 257 static void node_cacheinfo_release(struct device *dev) 258 { 259 struct node_cache_info *info = to_cache_info(dev); 260 kfree(info); 261 } 262 263 static void node_init_cache_dev(struct node *node) 264 { 265 struct device *dev; 266 267 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 268 if (!dev) 269 return; 270 271 device_initialize(dev); 272 dev->parent = &node->dev; 273 dev->release = node_cache_release; 274 if (dev_set_name(dev, "memory_side_cache")) 275 goto put_device; 276 277 if (device_add(dev)) 278 goto put_device; 279 280 pm_runtime_no_callbacks(dev); 281 node->cache_dev = dev; 282 return; 283 put_device: 284 put_device(dev); 285 } 286 287 /** 288 * node_add_cache() - add cache attribute to a memory node 289 * @nid: Node identifier that has new cache attributes 290 * @cache_attrs: Attributes for the cache being added 291 */ 292 void node_add_cache(unsigned int nid, struct node_cache_attrs *cache_attrs) 293 { 294 struct node_cache_info *info; 295 struct device *dev; 296 struct node *node; 297 298 if (!node_online(nid) || !node_devices[nid]) 299 return; 300 301 node = node_devices[nid]; 302 list_for_each_entry(info, &node->cache_attrs, node) { 303 if (info->cache_attrs.level == cache_attrs->level) { 304 dev_warn(&node->dev, 305 "attempt to add duplicate cache level:%d\n", 306 cache_attrs->level); 307 return; 308 } 309 } 310 311 if (!node->cache_dev) 312 node_init_cache_dev(node); 313 if (!node->cache_dev) 314 return; 315 316 info = kzalloc(sizeof(*info), GFP_KERNEL); 317 if (!info) 318 return; 319 320 dev = &info->dev; 321 device_initialize(dev); 322 dev->parent = node->cache_dev; 323 dev->release = node_cacheinfo_release; 324 dev->groups = cache_groups; 325 if (dev_set_name(dev, "index%d", cache_attrs->level)) 326 goto put_device; 327 328 info->cache_attrs = *cache_attrs; 329 if (device_add(dev)) { 330 dev_warn(&node->dev, "failed to add cache level:%d\n", 331 cache_attrs->level); 332 goto put_device; 333 } 334 pm_runtime_no_callbacks(dev); 335 list_add_tail(&info->node, &node->cache_attrs); 336 return; 337 put_device: 338 put_device(dev); 339 } 340 341 static void node_remove_caches(struct node *node) 342 { 343 struct node_cache_info *info, *next; 344 345 if (!node->cache_dev) 346 return; 347 348 list_for_each_entry_safe(info, next, &node->cache_attrs, node) { 349 list_del(&info->node); 350 device_unregister(&info->dev); 351 } 352 device_unregister(node->cache_dev); 353 } 354 355 static void node_init_caches(unsigned int nid) 356 { 357 INIT_LIST_HEAD(&node_devices[nid]->cache_attrs); 358 } 359 #else 360 static void node_init_caches(unsigned int nid) { } 361 static void node_remove_caches(struct node *node) { } 362 #endif 363 364 #define K(x) ((x) << (PAGE_SHIFT - 10)) 365 static ssize_t node_read_meminfo(struct device *dev, 366 struct device_attribute *attr, char *buf) 367 { 368 int len = 0; 369 int nid = dev->id; 370 struct pglist_data *pgdat = NODE_DATA(nid); 371 struct sysinfo i; 372 unsigned long sreclaimable, sunreclaimable; 373 unsigned long swapcached = 0; 374 375 si_meminfo_node(&i, nid); 376 sreclaimable = node_page_state_pages(pgdat, NR_SLAB_RECLAIMABLE_B); 377 sunreclaimable = node_page_state_pages(pgdat, NR_SLAB_UNRECLAIMABLE_B); 378 #ifdef CONFIG_SWAP 379 swapcached = node_page_state_pages(pgdat, NR_SWAPCACHE); 380 #endif 381 len = sysfs_emit_at(buf, len, 382 "Node %d MemTotal: %8lu kB\n" 383 "Node %d MemFree: %8lu kB\n" 384 "Node %d MemUsed: %8lu kB\n" 385 "Node %d SwapCached: %8lu kB\n" 386 "Node %d Active: %8lu kB\n" 387 "Node %d Inactive: %8lu kB\n" 388 "Node %d Active(anon): %8lu kB\n" 389 "Node %d Inactive(anon): %8lu kB\n" 390 "Node %d Active(file): %8lu kB\n" 391 "Node %d Inactive(file): %8lu kB\n" 392 "Node %d Unevictable: %8lu kB\n" 393 "Node %d Mlocked: %8lu kB\n", 394 nid, K(i.totalram), 395 nid, K(i.freeram), 396 nid, K(i.totalram - i.freeram), 397 nid, K(swapcached), 398 nid, K(node_page_state(pgdat, NR_ACTIVE_ANON) + 399 node_page_state(pgdat, NR_ACTIVE_FILE)), 400 nid, K(node_page_state(pgdat, NR_INACTIVE_ANON) + 401 node_page_state(pgdat, NR_INACTIVE_FILE)), 402 nid, K(node_page_state(pgdat, NR_ACTIVE_ANON)), 403 nid, K(node_page_state(pgdat, NR_INACTIVE_ANON)), 404 nid, K(node_page_state(pgdat, NR_ACTIVE_FILE)), 405 nid, K(node_page_state(pgdat, NR_INACTIVE_FILE)), 406 nid, K(node_page_state(pgdat, NR_UNEVICTABLE)), 407 nid, K(sum_zone_node_page_state(nid, NR_MLOCK))); 408 409 #ifdef CONFIG_HIGHMEM 410 len += sysfs_emit_at(buf, len, 411 "Node %d HighTotal: %8lu kB\n" 412 "Node %d HighFree: %8lu kB\n" 413 "Node %d LowTotal: %8lu kB\n" 414 "Node %d LowFree: %8lu kB\n", 415 nid, K(i.totalhigh), 416 nid, K(i.freehigh), 417 nid, K(i.totalram - i.totalhigh), 418 nid, K(i.freeram - i.freehigh)); 419 #endif 420 len += sysfs_emit_at(buf, len, 421 "Node %d Dirty: %8lu kB\n" 422 "Node %d Writeback: %8lu kB\n" 423 "Node %d FilePages: %8lu kB\n" 424 "Node %d Mapped: %8lu kB\n" 425 "Node %d AnonPages: %8lu kB\n" 426 "Node %d Shmem: %8lu kB\n" 427 "Node %d KernelStack: %8lu kB\n" 428 #ifdef CONFIG_SHADOW_CALL_STACK 429 "Node %d ShadowCallStack:%8lu kB\n" 430 #endif 431 "Node %d PageTables: %8lu kB\n" 432 "Node %d NFS_Unstable: %8lu kB\n" 433 "Node %d Bounce: %8lu kB\n" 434 "Node %d WritebackTmp: %8lu kB\n" 435 "Node %d KReclaimable: %8lu kB\n" 436 "Node %d Slab: %8lu kB\n" 437 "Node %d SReclaimable: %8lu kB\n" 438 "Node %d SUnreclaim: %8lu kB\n" 439 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 440 "Node %d AnonHugePages: %8lu kB\n" 441 "Node %d ShmemHugePages: %8lu kB\n" 442 "Node %d ShmemPmdMapped: %8lu kB\n" 443 "Node %d FileHugePages: %8lu kB\n" 444 "Node %d FilePmdMapped: %8lu kB\n" 445 #endif 446 , 447 nid, K(node_page_state(pgdat, NR_FILE_DIRTY)), 448 nid, K(node_page_state(pgdat, NR_WRITEBACK)), 449 nid, K(node_page_state(pgdat, NR_FILE_PAGES)), 450 nid, K(node_page_state(pgdat, NR_FILE_MAPPED)), 451 nid, K(node_page_state(pgdat, NR_ANON_MAPPED)), 452 nid, K(i.sharedram), 453 nid, node_page_state(pgdat, NR_KERNEL_STACK_KB), 454 #ifdef CONFIG_SHADOW_CALL_STACK 455 nid, node_page_state(pgdat, NR_KERNEL_SCS_KB), 456 #endif 457 nid, K(node_page_state(pgdat, NR_PAGETABLE)), 458 nid, 0UL, 459 nid, K(sum_zone_node_page_state(nid, NR_BOUNCE)), 460 nid, K(node_page_state(pgdat, NR_WRITEBACK_TEMP)), 461 nid, K(sreclaimable + 462 node_page_state(pgdat, NR_KERNEL_MISC_RECLAIMABLE)), 463 nid, K(sreclaimable + sunreclaimable), 464 nid, K(sreclaimable), 465 nid, K(sunreclaimable) 466 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 467 , 468 nid, K(node_page_state(pgdat, NR_ANON_THPS)), 469 nid, K(node_page_state(pgdat, NR_SHMEM_THPS)), 470 nid, K(node_page_state(pgdat, NR_SHMEM_PMDMAPPED)), 471 nid, K(node_page_state(pgdat, NR_FILE_THPS)), 472 nid, K(node_page_state(pgdat, NR_FILE_PMDMAPPED)) 473 #endif 474 ); 475 len += hugetlb_report_node_meminfo(buf, len, nid); 476 return len; 477 } 478 479 #undef K 480 static DEVICE_ATTR(meminfo, 0444, node_read_meminfo, NULL); 481 482 static ssize_t node_read_numastat(struct device *dev, 483 struct device_attribute *attr, char *buf) 484 { 485 fold_vm_numa_events(); 486 return sysfs_emit(buf, 487 "numa_hit %lu\n" 488 "numa_miss %lu\n" 489 "numa_foreign %lu\n" 490 "interleave_hit %lu\n" 491 "local_node %lu\n" 492 "other_node %lu\n", 493 sum_zone_numa_event_state(dev->id, NUMA_HIT), 494 sum_zone_numa_event_state(dev->id, NUMA_MISS), 495 sum_zone_numa_event_state(dev->id, NUMA_FOREIGN), 496 sum_zone_numa_event_state(dev->id, NUMA_INTERLEAVE_HIT), 497 sum_zone_numa_event_state(dev->id, NUMA_LOCAL), 498 sum_zone_numa_event_state(dev->id, NUMA_OTHER)); 499 } 500 static DEVICE_ATTR(numastat, 0444, node_read_numastat, NULL); 501 502 static ssize_t node_read_vmstat(struct device *dev, 503 struct device_attribute *attr, char *buf) 504 { 505 int nid = dev->id; 506 struct pglist_data *pgdat = NODE_DATA(nid); 507 int i; 508 int len = 0; 509 510 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) 511 len += sysfs_emit_at(buf, len, "%s %lu\n", 512 zone_stat_name(i), 513 sum_zone_node_page_state(nid, i)); 514 515 #ifdef CONFIG_NUMA 516 fold_vm_numa_events(); 517 for (i = 0; i < NR_VM_NUMA_EVENT_ITEMS; i++) 518 len += sysfs_emit_at(buf, len, "%s %lu\n", 519 numa_stat_name(i), 520 sum_zone_numa_event_state(nid, i)); 521 522 #endif 523 for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) { 524 unsigned long pages = node_page_state_pages(pgdat, i); 525 526 if (vmstat_item_print_in_thp(i)) 527 pages /= HPAGE_PMD_NR; 528 len += sysfs_emit_at(buf, len, "%s %lu\n", node_stat_name(i), 529 pages); 530 } 531 532 return len; 533 } 534 static DEVICE_ATTR(vmstat, 0444, node_read_vmstat, NULL); 535 536 static ssize_t node_read_distance(struct device *dev, 537 struct device_attribute *attr, char *buf) 538 { 539 int nid = dev->id; 540 int len = 0; 541 int i; 542 543 /* 544 * buf is currently PAGE_SIZE in length and each node needs 4 chars 545 * at the most (distance + space or newline). 546 */ 547 BUILD_BUG_ON(MAX_NUMNODES * 4 > PAGE_SIZE); 548 549 for_each_online_node(i) { 550 len += sysfs_emit_at(buf, len, "%s%d", 551 i ? " " : "", node_distance(nid, i)); 552 } 553 554 len += sysfs_emit_at(buf, len, "\n"); 555 return len; 556 } 557 static DEVICE_ATTR(distance, 0444, node_read_distance, NULL); 558 559 static struct attribute *node_dev_attrs[] = { 560 &dev_attr_cpumap.attr, 561 &dev_attr_cpulist.attr, 562 &dev_attr_meminfo.attr, 563 &dev_attr_numastat.attr, 564 &dev_attr_distance.attr, 565 &dev_attr_vmstat.attr, 566 NULL 567 }; 568 ATTRIBUTE_GROUPS(node_dev); 569 570 #ifdef CONFIG_HUGETLBFS 571 /* 572 * hugetlbfs per node attributes registration interface: 573 * When/if hugetlb[fs] subsystem initializes [sometime after this module], 574 * it will register its per node attributes for all online nodes with 575 * memory. It will also call register_hugetlbfs_with_node(), below, to 576 * register its attribute registration functions with this node driver. 577 * Once these hooks have been initialized, the node driver will call into 578 * the hugetlb module to [un]register attributes for hot-plugged nodes. 579 */ 580 static node_registration_func_t __hugetlb_register_node; 581 static node_registration_func_t __hugetlb_unregister_node; 582 583 static inline bool hugetlb_register_node(struct node *node) 584 { 585 if (__hugetlb_register_node && 586 node_state(node->dev.id, N_MEMORY)) { 587 __hugetlb_register_node(node); 588 return true; 589 } 590 return false; 591 } 592 593 static inline void hugetlb_unregister_node(struct node *node) 594 { 595 if (__hugetlb_unregister_node) 596 __hugetlb_unregister_node(node); 597 } 598 599 void register_hugetlbfs_with_node(node_registration_func_t doregister, 600 node_registration_func_t unregister) 601 { 602 __hugetlb_register_node = doregister; 603 __hugetlb_unregister_node = unregister; 604 } 605 #else 606 static inline void hugetlb_register_node(struct node *node) {} 607 608 static inline void hugetlb_unregister_node(struct node *node) {} 609 #endif 610 611 static void node_device_release(struct device *dev) 612 { 613 struct node *node = to_node(dev); 614 615 #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HUGETLBFS) 616 /* 617 * We schedule the work only when a memory section is 618 * onlined/offlined on this node. When we come here, 619 * all the memory on this node has been offlined, 620 * so we won't enqueue new work to this work. 621 * 622 * The work is using node->node_work, so we should 623 * flush work before freeing the memory. 624 */ 625 flush_work(&node->node_work); 626 #endif 627 kfree(node); 628 } 629 630 /* 631 * register_node - Setup a sysfs device for a node. 632 * @num - Node number to use when creating the device. 633 * 634 * Initialize and register the node device. 635 */ 636 static int register_node(struct node *node, int num) 637 { 638 int error; 639 640 node->dev.id = num; 641 node->dev.bus = &node_subsys; 642 node->dev.release = node_device_release; 643 node->dev.groups = node_dev_groups; 644 error = device_register(&node->dev); 645 646 if (error) 647 put_device(&node->dev); 648 else { 649 hugetlb_register_node(node); 650 651 compaction_register_node(node); 652 } 653 return error; 654 } 655 656 /** 657 * unregister_node - unregister a node device 658 * @node: node going away 659 * 660 * Unregisters a node device @node. All the devices on the node must be 661 * unregistered before calling this function. 662 */ 663 void unregister_node(struct node *node) 664 { 665 hugetlb_unregister_node(node); /* no-op, if memoryless node */ 666 node_remove_accesses(node); 667 node_remove_caches(node); 668 device_unregister(&node->dev); 669 } 670 671 struct node *node_devices[MAX_NUMNODES]; 672 673 /* 674 * register cpu under node 675 */ 676 int register_cpu_under_node(unsigned int cpu, unsigned int nid) 677 { 678 int ret; 679 struct device *obj; 680 681 if (!node_online(nid)) 682 return 0; 683 684 obj = get_cpu_device(cpu); 685 if (!obj) 686 return 0; 687 688 ret = sysfs_create_link(&node_devices[nid]->dev.kobj, 689 &obj->kobj, 690 kobject_name(&obj->kobj)); 691 if (ret) 692 return ret; 693 694 return sysfs_create_link(&obj->kobj, 695 &node_devices[nid]->dev.kobj, 696 kobject_name(&node_devices[nid]->dev.kobj)); 697 } 698 699 /** 700 * register_memory_node_under_compute_node - link memory node to its compute 701 * node for a given access class. 702 * @mem_nid: Memory node number 703 * @cpu_nid: Cpu node number 704 * @access: Access class to register 705 * 706 * Description: 707 * For use with platforms that may have separate memory and compute nodes. 708 * This function will export node relationships linking which memory 709 * initiator nodes can access memory targets at a given ranked access 710 * class. 711 */ 712 int register_memory_node_under_compute_node(unsigned int mem_nid, 713 unsigned int cpu_nid, 714 unsigned access) 715 { 716 struct node *init_node, *targ_node; 717 struct node_access_nodes *initiator, *target; 718 int ret; 719 720 if (!node_online(cpu_nid) || !node_online(mem_nid)) 721 return -ENODEV; 722 723 init_node = node_devices[cpu_nid]; 724 targ_node = node_devices[mem_nid]; 725 initiator = node_init_node_access(init_node, access); 726 target = node_init_node_access(targ_node, access); 727 if (!initiator || !target) 728 return -ENOMEM; 729 730 ret = sysfs_add_link_to_group(&initiator->dev.kobj, "targets", 731 &targ_node->dev.kobj, 732 dev_name(&targ_node->dev)); 733 if (ret) 734 return ret; 735 736 ret = sysfs_add_link_to_group(&target->dev.kobj, "initiators", 737 &init_node->dev.kobj, 738 dev_name(&init_node->dev)); 739 if (ret) 740 goto err; 741 742 return 0; 743 err: 744 sysfs_remove_link_from_group(&initiator->dev.kobj, "targets", 745 dev_name(&targ_node->dev)); 746 return ret; 747 } 748 749 int unregister_cpu_under_node(unsigned int cpu, unsigned int nid) 750 { 751 struct device *obj; 752 753 if (!node_online(nid)) 754 return 0; 755 756 obj = get_cpu_device(cpu); 757 if (!obj) 758 return 0; 759 760 sysfs_remove_link(&node_devices[nid]->dev.kobj, 761 kobject_name(&obj->kobj)); 762 sysfs_remove_link(&obj->kobj, 763 kobject_name(&node_devices[nid]->dev.kobj)); 764 765 return 0; 766 } 767 768 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE 769 static int __ref get_nid_for_pfn(unsigned long pfn) 770 { 771 if (!pfn_valid_within(pfn)) 772 return -1; 773 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT 774 if (system_state < SYSTEM_RUNNING) 775 return early_pfn_to_nid(pfn); 776 #endif 777 return pfn_to_nid(pfn); 778 } 779 780 static void do_register_memory_block_under_node(int nid, 781 struct memory_block *mem_blk) 782 { 783 int ret; 784 785 /* 786 * If this memory block spans multiple nodes, we only indicate 787 * the last processed node. 788 */ 789 mem_blk->nid = nid; 790 791 ret = sysfs_create_link_nowarn(&node_devices[nid]->dev.kobj, 792 &mem_blk->dev.kobj, 793 kobject_name(&mem_blk->dev.kobj)); 794 if (ret && ret != -EEXIST) 795 dev_err_ratelimited(&node_devices[nid]->dev, 796 "can't create link to %s in sysfs (%d)\n", 797 kobject_name(&mem_blk->dev.kobj), ret); 798 799 ret = sysfs_create_link_nowarn(&mem_blk->dev.kobj, 800 &node_devices[nid]->dev.kobj, 801 kobject_name(&node_devices[nid]->dev.kobj)); 802 if (ret && ret != -EEXIST) 803 dev_err_ratelimited(&mem_blk->dev, 804 "can't create link to %s in sysfs (%d)\n", 805 kobject_name(&node_devices[nid]->dev.kobj), 806 ret); 807 } 808 809 /* register memory section under specified node if it spans that node */ 810 static int register_mem_block_under_node_early(struct memory_block *mem_blk, 811 void *arg) 812 { 813 unsigned long memory_block_pfns = memory_block_size_bytes() / PAGE_SIZE; 814 unsigned long start_pfn = section_nr_to_pfn(mem_blk->start_section_nr); 815 unsigned long end_pfn = start_pfn + memory_block_pfns - 1; 816 int nid = *(int *)arg; 817 unsigned long pfn; 818 819 for (pfn = start_pfn; pfn <= end_pfn; pfn++) { 820 int page_nid; 821 822 /* 823 * memory block could have several absent sections from start. 824 * skip pfn range from absent section 825 */ 826 if (!pfn_in_present_section(pfn)) { 827 pfn = round_down(pfn + PAGES_PER_SECTION, 828 PAGES_PER_SECTION) - 1; 829 continue; 830 } 831 832 /* 833 * We need to check if page belongs to nid only at the boot 834 * case because node's ranges can be interleaved. 835 */ 836 page_nid = get_nid_for_pfn(pfn); 837 if (page_nid < 0) 838 continue; 839 if (page_nid != nid) 840 continue; 841 842 do_register_memory_block_under_node(nid, mem_blk); 843 return 0; 844 } 845 /* mem section does not span the specified node */ 846 return 0; 847 } 848 849 /* 850 * During hotplug we know that all pages in the memory block belong to the same 851 * node. 852 */ 853 static int register_mem_block_under_node_hotplug(struct memory_block *mem_blk, 854 void *arg) 855 { 856 int nid = *(int *)arg; 857 858 do_register_memory_block_under_node(nid, mem_blk); 859 return 0; 860 } 861 862 /* 863 * Unregister a memory block device under the node it spans. Memory blocks 864 * with multiple nodes cannot be offlined and therefore also never be removed. 865 */ 866 void unregister_memory_block_under_nodes(struct memory_block *mem_blk) 867 { 868 if (mem_blk->nid == NUMA_NO_NODE) 869 return; 870 871 sysfs_remove_link(&node_devices[mem_blk->nid]->dev.kobj, 872 kobject_name(&mem_blk->dev.kobj)); 873 sysfs_remove_link(&mem_blk->dev.kobj, 874 kobject_name(&node_devices[mem_blk->nid]->dev.kobj)); 875 } 876 877 void link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn, 878 enum meminit_context context) 879 { 880 walk_memory_blocks_func_t func; 881 882 if (context == MEMINIT_HOTPLUG) 883 func = register_mem_block_under_node_hotplug; 884 else 885 func = register_mem_block_under_node_early; 886 887 walk_memory_blocks(PFN_PHYS(start_pfn), PFN_PHYS(end_pfn - start_pfn), 888 (void *)&nid, func); 889 return; 890 } 891 892 #ifdef CONFIG_HUGETLBFS 893 /* 894 * Handle per node hstate attribute [un]registration on transistions 895 * to/from memoryless state. 896 */ 897 static void node_hugetlb_work(struct work_struct *work) 898 { 899 struct node *node = container_of(work, struct node, node_work); 900 901 /* 902 * We only get here when a node transitions to/from memoryless state. 903 * We can detect which transition occurred by examining whether the 904 * node has memory now. hugetlb_register_node() already check this 905 * so we try to register the attributes. If that fails, then the 906 * node has transitioned to memoryless, try to unregister the 907 * attributes. 908 */ 909 if (!hugetlb_register_node(node)) 910 hugetlb_unregister_node(node); 911 } 912 913 static void init_node_hugetlb_work(int nid) 914 { 915 INIT_WORK(&node_devices[nid]->node_work, node_hugetlb_work); 916 } 917 918 static int node_memory_callback(struct notifier_block *self, 919 unsigned long action, void *arg) 920 { 921 struct memory_notify *mnb = arg; 922 int nid = mnb->status_change_nid; 923 924 switch (action) { 925 case MEM_ONLINE: 926 case MEM_OFFLINE: 927 /* 928 * offload per node hstate [un]registration to a work thread 929 * when transitioning to/from memoryless state. 930 */ 931 if (nid != NUMA_NO_NODE) 932 schedule_work(&node_devices[nid]->node_work); 933 break; 934 935 case MEM_GOING_ONLINE: 936 case MEM_GOING_OFFLINE: 937 case MEM_CANCEL_ONLINE: 938 case MEM_CANCEL_OFFLINE: 939 default: 940 break; 941 } 942 943 return NOTIFY_OK; 944 } 945 #endif /* CONFIG_HUGETLBFS */ 946 #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */ 947 948 #if !defined(CONFIG_MEMORY_HOTPLUG_SPARSE) || \ 949 !defined(CONFIG_HUGETLBFS) 950 static inline int node_memory_callback(struct notifier_block *self, 951 unsigned long action, void *arg) 952 { 953 return NOTIFY_OK; 954 } 955 956 static void init_node_hugetlb_work(int nid) { } 957 958 #endif 959 960 int __register_one_node(int nid) 961 { 962 int error; 963 int cpu; 964 965 node_devices[nid] = kzalloc(sizeof(struct node), GFP_KERNEL); 966 if (!node_devices[nid]) 967 return -ENOMEM; 968 969 error = register_node(node_devices[nid], nid); 970 971 /* link cpu under this node */ 972 for_each_present_cpu(cpu) { 973 if (cpu_to_node(cpu) == nid) 974 register_cpu_under_node(cpu, nid); 975 } 976 977 INIT_LIST_HEAD(&node_devices[nid]->access_list); 978 /* initialize work queue for memory hot plug */ 979 init_node_hugetlb_work(nid); 980 node_init_caches(nid); 981 982 return error; 983 } 984 985 void unregister_one_node(int nid) 986 { 987 if (!node_devices[nid]) 988 return; 989 990 unregister_node(node_devices[nid]); 991 node_devices[nid] = NULL; 992 } 993 994 /* 995 * node states attributes 996 */ 997 998 struct node_attr { 999 struct device_attribute attr; 1000 enum node_states state; 1001 }; 1002 1003 static ssize_t show_node_state(struct device *dev, 1004 struct device_attribute *attr, char *buf) 1005 { 1006 struct node_attr *na = container_of(attr, struct node_attr, attr); 1007 1008 return sysfs_emit(buf, "%*pbl\n", 1009 nodemask_pr_args(&node_states[na->state])); 1010 } 1011 1012 #define _NODE_ATTR(name, state) \ 1013 { __ATTR(name, 0444, show_node_state, NULL), state } 1014 1015 static struct node_attr node_state_attr[] = { 1016 [N_POSSIBLE] = _NODE_ATTR(possible, N_POSSIBLE), 1017 [N_ONLINE] = _NODE_ATTR(online, N_ONLINE), 1018 [N_NORMAL_MEMORY] = _NODE_ATTR(has_normal_memory, N_NORMAL_MEMORY), 1019 #ifdef CONFIG_HIGHMEM 1020 [N_HIGH_MEMORY] = _NODE_ATTR(has_high_memory, N_HIGH_MEMORY), 1021 #endif 1022 [N_MEMORY] = _NODE_ATTR(has_memory, N_MEMORY), 1023 [N_CPU] = _NODE_ATTR(has_cpu, N_CPU), 1024 [N_GENERIC_INITIATOR] = _NODE_ATTR(has_generic_initiator, 1025 N_GENERIC_INITIATOR), 1026 }; 1027 1028 static struct attribute *node_state_attrs[] = { 1029 &node_state_attr[N_POSSIBLE].attr.attr, 1030 &node_state_attr[N_ONLINE].attr.attr, 1031 &node_state_attr[N_NORMAL_MEMORY].attr.attr, 1032 #ifdef CONFIG_HIGHMEM 1033 &node_state_attr[N_HIGH_MEMORY].attr.attr, 1034 #endif 1035 &node_state_attr[N_MEMORY].attr.attr, 1036 &node_state_attr[N_CPU].attr.attr, 1037 &node_state_attr[N_GENERIC_INITIATOR].attr.attr, 1038 NULL 1039 }; 1040 1041 static const struct attribute_group memory_root_attr_group = { 1042 .attrs = node_state_attrs, 1043 }; 1044 1045 static const struct attribute_group *cpu_root_attr_groups[] = { 1046 &memory_root_attr_group, 1047 NULL, 1048 }; 1049 1050 #define NODE_CALLBACK_PRI 2 /* lower than SLAB */ 1051 static int __init register_node_type(void) 1052 { 1053 int ret; 1054 1055 BUILD_BUG_ON(ARRAY_SIZE(node_state_attr) != NR_NODE_STATES); 1056 BUILD_BUG_ON(ARRAY_SIZE(node_state_attrs)-1 != NR_NODE_STATES); 1057 1058 ret = subsys_system_register(&node_subsys, cpu_root_attr_groups); 1059 if (!ret) { 1060 static struct notifier_block node_memory_callback_nb = { 1061 .notifier_call = node_memory_callback, 1062 .priority = NODE_CALLBACK_PRI, 1063 }; 1064 register_hotmemory_notifier(&node_memory_callback_nb); 1065 } 1066 1067 /* 1068 * Note: we're not going to unregister the node class if we fail 1069 * to register the node state class attribute files. 1070 */ 1071 return ret; 1072 } 1073 postcore_initcall(register_node_type); 1074