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 static inline ssize_t cpumap_read(struct file *file, struct kobject *kobj, 30 struct bin_attribute *attr, char *buf, 31 loff_t off, size_t count) 32 { 33 struct device *dev = kobj_to_dev(kobj); 34 struct node *node_dev = to_node(dev); 35 cpumask_var_t mask; 36 ssize_t n; 37 38 if (!alloc_cpumask_var(&mask, GFP_KERNEL)) 39 return 0; 40 41 cpumask_and(mask, cpumask_of_node(node_dev->dev.id), cpu_online_mask); 42 n = cpumap_print_bitmask_to_buf(buf, mask, off, count); 43 free_cpumask_var(mask); 44 45 return n; 46 } 47 48 static BIN_ATTR_RO(cpumap, 0); 49 50 static inline ssize_t cpulist_read(struct file *file, struct kobject *kobj, 51 struct bin_attribute *attr, char *buf, 52 loff_t off, size_t count) 53 { 54 struct device *dev = kobj_to_dev(kobj); 55 struct node *node_dev = to_node(dev); 56 cpumask_var_t mask; 57 ssize_t n; 58 59 if (!alloc_cpumask_var(&mask, GFP_KERNEL)) 60 return 0; 61 62 cpumask_and(mask, cpumask_of_node(node_dev->dev.id), cpu_online_mask); 63 n = cpumap_print_list_to_buf(buf, mask, off, count); 64 free_cpumask_var(mask); 65 66 return n; 67 } 68 69 static BIN_ATTR_RO(cpulist, 0); 70 71 /** 72 * struct node_access_nodes - Access class device to hold user visible 73 * relationships to other nodes. 74 * @dev: Device for this memory access class 75 * @list_node: List element in the node's access list 76 * @access: The access class rank 77 * @hmem_attrs: Heterogeneous memory performance attributes 78 */ 79 struct node_access_nodes { 80 struct device dev; 81 struct list_head list_node; 82 unsigned int access; 83 #ifdef CONFIG_HMEM_REPORTING 84 struct node_hmem_attrs hmem_attrs; 85 #endif 86 }; 87 #define to_access_nodes(dev) container_of(dev, struct node_access_nodes, dev) 88 89 static struct attribute *node_init_access_node_attrs[] = { 90 NULL, 91 }; 92 93 static struct attribute *node_targ_access_node_attrs[] = { 94 NULL, 95 }; 96 97 static const struct attribute_group initiators = { 98 .name = "initiators", 99 .attrs = node_init_access_node_attrs, 100 }; 101 102 static const struct attribute_group targets = { 103 .name = "targets", 104 .attrs = node_targ_access_node_attrs, 105 }; 106 107 static const struct attribute_group *node_access_node_groups[] = { 108 &initiators, 109 &targets, 110 NULL, 111 }; 112 113 static void node_remove_accesses(struct node *node) 114 { 115 struct node_access_nodes *c, *cnext; 116 117 list_for_each_entry_safe(c, cnext, &node->access_list, list_node) { 118 list_del(&c->list_node); 119 device_unregister(&c->dev); 120 } 121 } 122 123 static void node_access_release(struct device *dev) 124 { 125 kfree(to_access_nodes(dev)); 126 } 127 128 static struct node_access_nodes *node_init_node_access(struct node *node, 129 unsigned int access) 130 { 131 struct node_access_nodes *access_node; 132 struct device *dev; 133 134 list_for_each_entry(access_node, &node->access_list, list_node) 135 if (access_node->access == access) 136 return access_node; 137 138 access_node = kzalloc(sizeof(*access_node), GFP_KERNEL); 139 if (!access_node) 140 return NULL; 141 142 access_node->access = access; 143 dev = &access_node->dev; 144 dev->parent = &node->dev; 145 dev->release = node_access_release; 146 dev->groups = node_access_node_groups; 147 if (dev_set_name(dev, "access%u", access)) 148 goto free; 149 150 if (device_register(dev)) 151 goto free_name; 152 153 pm_runtime_no_callbacks(dev); 154 list_add_tail(&access_node->list_node, &node->access_list); 155 return access_node; 156 free_name: 157 kfree_const(dev->kobj.name); 158 free: 159 kfree(access_node); 160 return NULL; 161 } 162 163 #ifdef CONFIG_HMEM_REPORTING 164 #define ACCESS_ATTR(name) \ 165 static ssize_t name##_show(struct device *dev, \ 166 struct device_attribute *attr, \ 167 char *buf) \ 168 { \ 169 return sysfs_emit(buf, "%u\n", \ 170 to_access_nodes(dev)->hmem_attrs.name); \ 171 } \ 172 static DEVICE_ATTR_RO(name) 173 174 ACCESS_ATTR(read_bandwidth); 175 ACCESS_ATTR(read_latency); 176 ACCESS_ATTR(write_bandwidth); 177 ACCESS_ATTR(write_latency); 178 179 static struct attribute *access_attrs[] = { 180 &dev_attr_read_bandwidth.attr, 181 &dev_attr_read_latency.attr, 182 &dev_attr_write_bandwidth.attr, 183 &dev_attr_write_latency.attr, 184 NULL, 185 }; 186 187 /** 188 * node_set_perf_attrs - Set the performance values for given access class 189 * @nid: Node identifier to be set 190 * @hmem_attrs: Heterogeneous memory performance attributes 191 * @access: The access class the for the given attributes 192 */ 193 void node_set_perf_attrs(unsigned int nid, struct node_hmem_attrs *hmem_attrs, 194 unsigned int access) 195 { 196 struct node_access_nodes *c; 197 struct node *node; 198 int i; 199 200 if (WARN_ON_ONCE(!node_online(nid))) 201 return; 202 203 node = node_devices[nid]; 204 c = node_init_node_access(node, access); 205 if (!c) 206 return; 207 208 c->hmem_attrs = *hmem_attrs; 209 for (i = 0; access_attrs[i] != NULL; i++) { 210 if (sysfs_add_file_to_group(&c->dev.kobj, access_attrs[i], 211 "initiators")) { 212 pr_info("failed to add performance attribute to node %d\n", 213 nid); 214 break; 215 } 216 } 217 } 218 219 /** 220 * struct node_cache_info - Internal tracking for memory node caches 221 * @dev: Device represeting the cache level 222 * @node: List element for tracking in the node 223 * @cache_attrs:Attributes for this cache level 224 */ 225 struct node_cache_info { 226 struct device dev; 227 struct list_head node; 228 struct node_cache_attrs cache_attrs; 229 }; 230 #define to_cache_info(device) container_of(device, struct node_cache_info, dev) 231 232 #define CACHE_ATTR(name, fmt) \ 233 static ssize_t name##_show(struct device *dev, \ 234 struct device_attribute *attr, \ 235 char *buf) \ 236 { \ 237 return sysfs_emit(buf, fmt "\n", \ 238 to_cache_info(dev)->cache_attrs.name); \ 239 } \ 240 static DEVICE_ATTR_RO(name); 241 242 CACHE_ATTR(size, "%llu") 243 CACHE_ATTR(line_size, "%u") 244 CACHE_ATTR(indexing, "%u") 245 CACHE_ATTR(write_policy, "%u") 246 247 static struct attribute *cache_attrs[] = { 248 &dev_attr_indexing.attr, 249 &dev_attr_size.attr, 250 &dev_attr_line_size.attr, 251 &dev_attr_write_policy.attr, 252 NULL, 253 }; 254 ATTRIBUTE_GROUPS(cache); 255 256 static void node_cache_release(struct device *dev) 257 { 258 kfree(dev); 259 } 260 261 static void node_cacheinfo_release(struct device *dev) 262 { 263 struct node_cache_info *info = to_cache_info(dev); 264 kfree(info); 265 } 266 267 static void node_init_cache_dev(struct node *node) 268 { 269 struct device *dev; 270 271 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 272 if (!dev) 273 return; 274 275 device_initialize(dev); 276 dev->parent = &node->dev; 277 dev->release = node_cache_release; 278 if (dev_set_name(dev, "memory_side_cache")) 279 goto put_device; 280 281 if (device_add(dev)) 282 goto put_device; 283 284 pm_runtime_no_callbacks(dev); 285 node->cache_dev = dev; 286 return; 287 put_device: 288 put_device(dev); 289 } 290 291 /** 292 * node_add_cache() - add cache attribute to a memory node 293 * @nid: Node identifier that has new cache attributes 294 * @cache_attrs: Attributes for the cache being added 295 */ 296 void node_add_cache(unsigned int nid, struct node_cache_attrs *cache_attrs) 297 { 298 struct node_cache_info *info; 299 struct device *dev; 300 struct node *node; 301 302 if (!node_online(nid) || !node_devices[nid]) 303 return; 304 305 node = node_devices[nid]; 306 list_for_each_entry(info, &node->cache_attrs, node) { 307 if (info->cache_attrs.level == cache_attrs->level) { 308 dev_warn(&node->dev, 309 "attempt to add duplicate cache level:%d\n", 310 cache_attrs->level); 311 return; 312 } 313 } 314 315 if (!node->cache_dev) 316 node_init_cache_dev(node); 317 if (!node->cache_dev) 318 return; 319 320 info = kzalloc(sizeof(*info), GFP_KERNEL); 321 if (!info) 322 return; 323 324 dev = &info->dev; 325 device_initialize(dev); 326 dev->parent = node->cache_dev; 327 dev->release = node_cacheinfo_release; 328 dev->groups = cache_groups; 329 if (dev_set_name(dev, "index%d", cache_attrs->level)) 330 goto put_device; 331 332 info->cache_attrs = *cache_attrs; 333 if (device_add(dev)) { 334 dev_warn(&node->dev, "failed to add cache level:%d\n", 335 cache_attrs->level); 336 goto put_device; 337 } 338 pm_runtime_no_callbacks(dev); 339 list_add_tail(&info->node, &node->cache_attrs); 340 return; 341 put_device: 342 put_device(dev); 343 } 344 345 static void node_remove_caches(struct node *node) 346 { 347 struct node_cache_info *info, *next; 348 349 if (!node->cache_dev) 350 return; 351 352 list_for_each_entry_safe(info, next, &node->cache_attrs, node) { 353 list_del(&info->node); 354 device_unregister(&info->dev); 355 } 356 device_unregister(node->cache_dev); 357 } 358 359 static void node_init_caches(unsigned int nid) 360 { 361 INIT_LIST_HEAD(&node_devices[nid]->cache_attrs); 362 } 363 #else 364 static void node_init_caches(unsigned int nid) { } 365 static void node_remove_caches(struct node *node) { } 366 #endif 367 368 #define K(x) ((x) << (PAGE_SHIFT - 10)) 369 static ssize_t node_read_meminfo(struct device *dev, 370 struct device_attribute *attr, char *buf) 371 { 372 int len = 0; 373 int nid = dev->id; 374 struct pglist_data *pgdat = NODE_DATA(nid); 375 struct sysinfo i; 376 unsigned long sreclaimable, sunreclaimable; 377 unsigned long swapcached = 0; 378 379 si_meminfo_node(&i, nid); 380 sreclaimable = node_page_state_pages(pgdat, NR_SLAB_RECLAIMABLE_B); 381 sunreclaimable = node_page_state_pages(pgdat, NR_SLAB_UNRECLAIMABLE_B); 382 #ifdef CONFIG_SWAP 383 swapcached = node_page_state_pages(pgdat, NR_SWAPCACHE); 384 #endif 385 len = sysfs_emit_at(buf, len, 386 "Node %d MemTotal: %8lu kB\n" 387 "Node %d MemFree: %8lu kB\n" 388 "Node %d MemUsed: %8lu kB\n" 389 "Node %d SwapCached: %8lu kB\n" 390 "Node %d Active: %8lu kB\n" 391 "Node %d Inactive: %8lu kB\n" 392 "Node %d Active(anon): %8lu kB\n" 393 "Node %d Inactive(anon): %8lu kB\n" 394 "Node %d Active(file): %8lu kB\n" 395 "Node %d Inactive(file): %8lu kB\n" 396 "Node %d Unevictable: %8lu kB\n" 397 "Node %d Mlocked: %8lu kB\n", 398 nid, K(i.totalram), 399 nid, K(i.freeram), 400 nid, K(i.totalram - i.freeram), 401 nid, K(swapcached), 402 nid, K(node_page_state(pgdat, NR_ACTIVE_ANON) + 403 node_page_state(pgdat, NR_ACTIVE_FILE)), 404 nid, K(node_page_state(pgdat, NR_INACTIVE_ANON) + 405 node_page_state(pgdat, NR_INACTIVE_FILE)), 406 nid, K(node_page_state(pgdat, NR_ACTIVE_ANON)), 407 nid, K(node_page_state(pgdat, NR_INACTIVE_ANON)), 408 nid, K(node_page_state(pgdat, NR_ACTIVE_FILE)), 409 nid, K(node_page_state(pgdat, NR_INACTIVE_FILE)), 410 nid, K(node_page_state(pgdat, NR_UNEVICTABLE)), 411 nid, K(sum_zone_node_page_state(nid, NR_MLOCK))); 412 413 #ifdef CONFIG_HIGHMEM 414 len += sysfs_emit_at(buf, len, 415 "Node %d HighTotal: %8lu kB\n" 416 "Node %d HighFree: %8lu kB\n" 417 "Node %d LowTotal: %8lu kB\n" 418 "Node %d LowFree: %8lu kB\n", 419 nid, K(i.totalhigh), 420 nid, K(i.freehigh), 421 nid, K(i.totalram - i.totalhigh), 422 nid, K(i.freeram - i.freehigh)); 423 #endif 424 len += sysfs_emit_at(buf, len, 425 "Node %d Dirty: %8lu kB\n" 426 "Node %d Writeback: %8lu kB\n" 427 "Node %d FilePages: %8lu kB\n" 428 "Node %d Mapped: %8lu kB\n" 429 "Node %d AnonPages: %8lu kB\n" 430 "Node %d Shmem: %8lu kB\n" 431 "Node %d KernelStack: %8lu kB\n" 432 #ifdef CONFIG_SHADOW_CALL_STACK 433 "Node %d ShadowCallStack:%8lu kB\n" 434 #endif 435 "Node %d PageTables: %8lu kB\n" 436 "Node %d NFS_Unstable: %8lu kB\n" 437 "Node %d Bounce: %8lu kB\n" 438 "Node %d WritebackTmp: %8lu kB\n" 439 "Node %d KReclaimable: %8lu kB\n" 440 "Node %d Slab: %8lu kB\n" 441 "Node %d SReclaimable: %8lu kB\n" 442 "Node %d SUnreclaim: %8lu kB\n" 443 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 444 "Node %d AnonHugePages: %8lu kB\n" 445 "Node %d ShmemHugePages: %8lu kB\n" 446 "Node %d ShmemPmdMapped: %8lu kB\n" 447 "Node %d FileHugePages: %8lu kB\n" 448 "Node %d FilePmdMapped: %8lu kB\n" 449 #endif 450 , 451 nid, K(node_page_state(pgdat, NR_FILE_DIRTY)), 452 nid, K(node_page_state(pgdat, NR_WRITEBACK)), 453 nid, K(node_page_state(pgdat, NR_FILE_PAGES)), 454 nid, K(node_page_state(pgdat, NR_FILE_MAPPED)), 455 nid, K(node_page_state(pgdat, NR_ANON_MAPPED)), 456 nid, K(i.sharedram), 457 nid, node_page_state(pgdat, NR_KERNEL_STACK_KB), 458 #ifdef CONFIG_SHADOW_CALL_STACK 459 nid, node_page_state(pgdat, NR_KERNEL_SCS_KB), 460 #endif 461 nid, K(node_page_state(pgdat, NR_PAGETABLE)), 462 nid, 0UL, 463 nid, K(sum_zone_node_page_state(nid, NR_BOUNCE)), 464 nid, K(node_page_state(pgdat, NR_WRITEBACK_TEMP)), 465 nid, K(sreclaimable + 466 node_page_state(pgdat, NR_KERNEL_MISC_RECLAIMABLE)), 467 nid, K(sreclaimable + sunreclaimable), 468 nid, K(sreclaimable), 469 nid, K(sunreclaimable) 470 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 471 , 472 nid, K(node_page_state(pgdat, NR_ANON_THPS)), 473 nid, K(node_page_state(pgdat, NR_SHMEM_THPS)), 474 nid, K(node_page_state(pgdat, NR_SHMEM_PMDMAPPED)), 475 nid, K(node_page_state(pgdat, NR_FILE_THPS)), 476 nid, K(node_page_state(pgdat, NR_FILE_PMDMAPPED)) 477 #endif 478 ); 479 len += hugetlb_report_node_meminfo(buf, len, nid); 480 return len; 481 } 482 483 #undef K 484 static DEVICE_ATTR(meminfo, 0444, node_read_meminfo, NULL); 485 486 static ssize_t node_read_numastat(struct device *dev, 487 struct device_attribute *attr, char *buf) 488 { 489 fold_vm_numa_events(); 490 return sysfs_emit(buf, 491 "numa_hit %lu\n" 492 "numa_miss %lu\n" 493 "numa_foreign %lu\n" 494 "interleave_hit %lu\n" 495 "local_node %lu\n" 496 "other_node %lu\n", 497 sum_zone_numa_event_state(dev->id, NUMA_HIT), 498 sum_zone_numa_event_state(dev->id, NUMA_MISS), 499 sum_zone_numa_event_state(dev->id, NUMA_FOREIGN), 500 sum_zone_numa_event_state(dev->id, NUMA_INTERLEAVE_HIT), 501 sum_zone_numa_event_state(dev->id, NUMA_LOCAL), 502 sum_zone_numa_event_state(dev->id, NUMA_OTHER)); 503 } 504 static DEVICE_ATTR(numastat, 0444, node_read_numastat, NULL); 505 506 static ssize_t node_read_vmstat(struct device *dev, 507 struct device_attribute *attr, char *buf) 508 { 509 int nid = dev->id; 510 struct pglist_data *pgdat = NODE_DATA(nid); 511 int i; 512 int len = 0; 513 514 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) 515 len += sysfs_emit_at(buf, len, "%s %lu\n", 516 zone_stat_name(i), 517 sum_zone_node_page_state(nid, i)); 518 519 #ifdef CONFIG_NUMA 520 fold_vm_numa_events(); 521 for (i = 0; i < NR_VM_NUMA_EVENT_ITEMS; i++) 522 len += sysfs_emit_at(buf, len, "%s %lu\n", 523 numa_stat_name(i), 524 sum_zone_numa_event_state(nid, i)); 525 526 #endif 527 for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) { 528 unsigned long pages = node_page_state_pages(pgdat, i); 529 530 if (vmstat_item_print_in_thp(i)) 531 pages /= HPAGE_PMD_NR; 532 len += sysfs_emit_at(buf, len, "%s %lu\n", node_stat_name(i), 533 pages); 534 } 535 536 return len; 537 } 538 static DEVICE_ATTR(vmstat, 0444, node_read_vmstat, NULL); 539 540 static ssize_t node_read_distance(struct device *dev, 541 struct device_attribute *attr, char *buf) 542 { 543 int nid = dev->id; 544 int len = 0; 545 int i; 546 547 /* 548 * buf is currently PAGE_SIZE in length and each node needs 4 chars 549 * at the most (distance + space or newline). 550 */ 551 BUILD_BUG_ON(MAX_NUMNODES * 4 > PAGE_SIZE); 552 553 for_each_online_node(i) { 554 len += sysfs_emit_at(buf, len, "%s%d", 555 i ? " " : "", node_distance(nid, i)); 556 } 557 558 len += sysfs_emit_at(buf, len, "\n"); 559 return len; 560 } 561 static DEVICE_ATTR(distance, 0444, node_read_distance, NULL); 562 563 static struct attribute *node_dev_attrs[] = { 564 &dev_attr_meminfo.attr, 565 &dev_attr_numastat.attr, 566 &dev_attr_distance.attr, 567 &dev_attr_vmstat.attr, 568 NULL 569 }; 570 571 static struct bin_attribute *node_dev_bin_attrs[] = { 572 &bin_attr_cpumap, 573 &bin_attr_cpulist, 574 NULL 575 }; 576 577 static const struct attribute_group node_dev_group = { 578 .attrs = node_dev_attrs, 579 .bin_attrs = node_dev_bin_attrs 580 }; 581 582 static const struct attribute_group *node_dev_groups[] = { 583 &node_dev_group, 584 #ifdef CONFIG_HAVE_ARCH_NODE_DEV_GROUP 585 &arch_node_dev_group, 586 #endif 587 NULL 588 }; 589 590 #ifdef CONFIG_HUGETLBFS 591 /* 592 * hugetlbfs per node attributes registration interface: 593 * When/if hugetlb[fs] subsystem initializes [sometime after this module], 594 * it will register its per node attributes for all online nodes with 595 * memory. It will also call register_hugetlbfs_with_node(), below, to 596 * register its attribute registration functions with this node driver. 597 * Once these hooks have been initialized, the node driver will call into 598 * the hugetlb module to [un]register attributes for hot-plugged nodes. 599 */ 600 static node_registration_func_t __hugetlb_register_node; 601 static node_registration_func_t __hugetlb_unregister_node; 602 603 static inline bool hugetlb_register_node(struct node *node) 604 { 605 if (__hugetlb_register_node && 606 node_state(node->dev.id, N_MEMORY)) { 607 __hugetlb_register_node(node); 608 return true; 609 } 610 return false; 611 } 612 613 static inline void hugetlb_unregister_node(struct node *node) 614 { 615 if (__hugetlb_unregister_node) 616 __hugetlb_unregister_node(node); 617 } 618 619 void register_hugetlbfs_with_node(node_registration_func_t doregister, 620 node_registration_func_t unregister) 621 { 622 __hugetlb_register_node = doregister; 623 __hugetlb_unregister_node = unregister; 624 } 625 #else 626 static inline void hugetlb_register_node(struct node *node) {} 627 628 static inline void hugetlb_unregister_node(struct node *node) {} 629 #endif 630 631 static void node_device_release(struct device *dev) 632 { 633 struct node *node = to_node(dev); 634 635 #if defined(CONFIG_MEMORY_HOTPLUG) && defined(CONFIG_HUGETLBFS) 636 /* 637 * We schedule the work only when a memory section is 638 * onlined/offlined on this node. When we come here, 639 * all the memory on this node has been offlined, 640 * so we won't enqueue new work to this work. 641 * 642 * The work is using node->node_work, so we should 643 * flush work before freeing the memory. 644 */ 645 flush_work(&node->node_work); 646 #endif 647 kfree(node); 648 } 649 650 /* 651 * register_node - Setup a sysfs device for a node. 652 * @num - Node number to use when creating the device. 653 * 654 * Initialize and register the node device. 655 */ 656 static int register_node(struct node *node, int num) 657 { 658 int error; 659 660 node->dev.id = num; 661 node->dev.bus = &node_subsys; 662 node->dev.release = node_device_release; 663 node->dev.groups = node_dev_groups; 664 error = device_register(&node->dev); 665 666 if (error) 667 put_device(&node->dev); 668 else { 669 hugetlb_register_node(node); 670 671 compaction_register_node(node); 672 } 673 return error; 674 } 675 676 /** 677 * unregister_node - unregister a node device 678 * @node: node going away 679 * 680 * Unregisters a node device @node. All the devices on the node must be 681 * unregistered before calling this function. 682 */ 683 void unregister_node(struct node *node) 684 { 685 compaction_unregister_node(node); 686 hugetlb_unregister_node(node); /* no-op, if memoryless node */ 687 node_remove_accesses(node); 688 node_remove_caches(node); 689 device_unregister(&node->dev); 690 } 691 692 struct node *node_devices[MAX_NUMNODES]; 693 694 /* 695 * register cpu under node 696 */ 697 int register_cpu_under_node(unsigned int cpu, unsigned int nid) 698 { 699 int ret; 700 struct device *obj; 701 702 if (!node_online(nid)) 703 return 0; 704 705 obj = get_cpu_device(cpu); 706 if (!obj) 707 return 0; 708 709 ret = sysfs_create_link(&node_devices[nid]->dev.kobj, 710 &obj->kobj, 711 kobject_name(&obj->kobj)); 712 if (ret) 713 return ret; 714 715 return sysfs_create_link(&obj->kobj, 716 &node_devices[nid]->dev.kobj, 717 kobject_name(&node_devices[nid]->dev.kobj)); 718 } 719 720 /** 721 * register_memory_node_under_compute_node - link memory node to its compute 722 * node for a given access class. 723 * @mem_nid: Memory node number 724 * @cpu_nid: Cpu node number 725 * @access: Access class to register 726 * 727 * Description: 728 * For use with platforms that may have separate memory and compute nodes. 729 * This function will export node relationships linking which memory 730 * initiator nodes can access memory targets at a given ranked access 731 * class. 732 */ 733 int register_memory_node_under_compute_node(unsigned int mem_nid, 734 unsigned int cpu_nid, 735 unsigned int access) 736 { 737 struct node *init_node, *targ_node; 738 struct node_access_nodes *initiator, *target; 739 int ret; 740 741 if (!node_online(cpu_nid) || !node_online(mem_nid)) 742 return -ENODEV; 743 744 init_node = node_devices[cpu_nid]; 745 targ_node = node_devices[mem_nid]; 746 initiator = node_init_node_access(init_node, access); 747 target = node_init_node_access(targ_node, access); 748 if (!initiator || !target) 749 return -ENOMEM; 750 751 ret = sysfs_add_link_to_group(&initiator->dev.kobj, "targets", 752 &targ_node->dev.kobj, 753 dev_name(&targ_node->dev)); 754 if (ret) 755 return ret; 756 757 ret = sysfs_add_link_to_group(&target->dev.kobj, "initiators", 758 &init_node->dev.kobj, 759 dev_name(&init_node->dev)); 760 if (ret) 761 goto err; 762 763 return 0; 764 err: 765 sysfs_remove_link_from_group(&initiator->dev.kobj, "targets", 766 dev_name(&targ_node->dev)); 767 return ret; 768 } 769 770 int unregister_cpu_under_node(unsigned int cpu, unsigned int nid) 771 { 772 struct device *obj; 773 774 if (!node_online(nid)) 775 return 0; 776 777 obj = get_cpu_device(cpu); 778 if (!obj) 779 return 0; 780 781 sysfs_remove_link(&node_devices[nid]->dev.kobj, 782 kobject_name(&obj->kobj)); 783 sysfs_remove_link(&obj->kobj, 784 kobject_name(&node_devices[nid]->dev.kobj)); 785 786 return 0; 787 } 788 789 #ifdef CONFIG_MEMORY_HOTPLUG 790 static int __ref get_nid_for_pfn(unsigned long pfn) 791 { 792 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT 793 if (system_state < SYSTEM_RUNNING) 794 return early_pfn_to_nid(pfn); 795 #endif 796 return pfn_to_nid(pfn); 797 } 798 799 static void do_register_memory_block_under_node(int nid, 800 struct memory_block *mem_blk, 801 enum meminit_context context) 802 { 803 int ret; 804 805 memory_block_add_nid(mem_blk, nid, context); 806 807 ret = sysfs_create_link_nowarn(&node_devices[nid]->dev.kobj, 808 &mem_blk->dev.kobj, 809 kobject_name(&mem_blk->dev.kobj)); 810 if (ret && ret != -EEXIST) 811 dev_err_ratelimited(&node_devices[nid]->dev, 812 "can't create link to %s in sysfs (%d)\n", 813 kobject_name(&mem_blk->dev.kobj), ret); 814 815 ret = sysfs_create_link_nowarn(&mem_blk->dev.kobj, 816 &node_devices[nid]->dev.kobj, 817 kobject_name(&node_devices[nid]->dev.kobj)); 818 if (ret && ret != -EEXIST) 819 dev_err_ratelimited(&mem_blk->dev, 820 "can't create link to %s in sysfs (%d)\n", 821 kobject_name(&node_devices[nid]->dev.kobj), 822 ret); 823 } 824 825 /* register memory section under specified node if it spans that node */ 826 static int register_mem_block_under_node_early(struct memory_block *mem_blk, 827 void *arg) 828 { 829 unsigned long memory_block_pfns = memory_block_size_bytes() / PAGE_SIZE; 830 unsigned long start_pfn = section_nr_to_pfn(mem_blk->start_section_nr); 831 unsigned long end_pfn = start_pfn + memory_block_pfns - 1; 832 int nid = *(int *)arg; 833 unsigned long pfn; 834 835 for (pfn = start_pfn; pfn <= end_pfn; pfn++) { 836 int page_nid; 837 838 /* 839 * memory block could have several absent sections from start. 840 * skip pfn range from absent section 841 */ 842 if (!pfn_in_present_section(pfn)) { 843 pfn = round_down(pfn + PAGES_PER_SECTION, 844 PAGES_PER_SECTION) - 1; 845 continue; 846 } 847 848 /* 849 * We need to check if page belongs to nid only at the boot 850 * case because node's ranges can be interleaved. 851 */ 852 page_nid = get_nid_for_pfn(pfn); 853 if (page_nid < 0) 854 continue; 855 if (page_nid != nid) 856 continue; 857 858 do_register_memory_block_under_node(nid, mem_blk, MEMINIT_EARLY); 859 return 0; 860 } 861 /* mem section does not span the specified node */ 862 return 0; 863 } 864 865 /* 866 * During hotplug we know that all pages in the memory block belong to the same 867 * node. 868 */ 869 static int register_mem_block_under_node_hotplug(struct memory_block *mem_blk, 870 void *arg) 871 { 872 int nid = *(int *)arg; 873 874 do_register_memory_block_under_node(nid, mem_blk, MEMINIT_HOTPLUG); 875 return 0; 876 } 877 878 /* 879 * Unregister a memory block device under the node it spans. Memory blocks 880 * with multiple nodes cannot be offlined and therefore also never be removed. 881 */ 882 void unregister_memory_block_under_nodes(struct memory_block *mem_blk) 883 { 884 if (mem_blk->nid == NUMA_NO_NODE) 885 return; 886 887 sysfs_remove_link(&node_devices[mem_blk->nid]->dev.kobj, 888 kobject_name(&mem_blk->dev.kobj)); 889 sysfs_remove_link(&mem_blk->dev.kobj, 890 kobject_name(&node_devices[mem_blk->nid]->dev.kobj)); 891 } 892 893 void register_memory_blocks_under_node(int nid, unsigned long start_pfn, 894 unsigned long end_pfn, 895 enum meminit_context context) 896 { 897 walk_memory_blocks_func_t func; 898 899 if (context == MEMINIT_HOTPLUG) 900 func = register_mem_block_under_node_hotplug; 901 else 902 func = register_mem_block_under_node_early; 903 904 walk_memory_blocks(PFN_PHYS(start_pfn), PFN_PHYS(end_pfn - start_pfn), 905 (void *)&nid, func); 906 return; 907 } 908 909 #ifdef CONFIG_HUGETLBFS 910 /* 911 * Handle per node hstate attribute [un]registration on transistions 912 * to/from memoryless state. 913 */ 914 static void node_hugetlb_work(struct work_struct *work) 915 { 916 struct node *node = container_of(work, struct node, node_work); 917 918 /* 919 * We only get here when a node transitions to/from memoryless state. 920 * We can detect which transition occurred by examining whether the 921 * node has memory now. hugetlb_register_node() already check this 922 * so we try to register the attributes. If that fails, then the 923 * node has transitioned to memoryless, try to unregister the 924 * attributes. 925 */ 926 if (!hugetlb_register_node(node)) 927 hugetlb_unregister_node(node); 928 } 929 930 static void init_node_hugetlb_work(int nid) 931 { 932 INIT_WORK(&node_devices[nid]->node_work, node_hugetlb_work); 933 } 934 935 static int node_memory_callback(struct notifier_block *self, 936 unsigned long action, void *arg) 937 { 938 struct memory_notify *mnb = arg; 939 int nid = mnb->status_change_nid; 940 941 switch (action) { 942 case MEM_ONLINE: 943 case MEM_OFFLINE: 944 /* 945 * offload per node hstate [un]registration to a work thread 946 * when transitioning to/from memoryless state. 947 */ 948 if (nid != NUMA_NO_NODE) 949 schedule_work(&node_devices[nid]->node_work); 950 break; 951 952 case MEM_GOING_ONLINE: 953 case MEM_GOING_OFFLINE: 954 case MEM_CANCEL_ONLINE: 955 case MEM_CANCEL_OFFLINE: 956 default: 957 break; 958 } 959 960 return NOTIFY_OK; 961 } 962 #endif /* CONFIG_HUGETLBFS */ 963 #endif /* CONFIG_MEMORY_HOTPLUG */ 964 965 #if !defined(CONFIG_MEMORY_HOTPLUG) || !defined(CONFIG_HUGETLBFS) 966 static inline int node_memory_callback(struct notifier_block *self, 967 unsigned long action, void *arg) 968 { 969 return NOTIFY_OK; 970 } 971 972 static void init_node_hugetlb_work(int nid) { } 973 974 #endif 975 976 int __register_one_node(int nid) 977 { 978 int error; 979 int cpu; 980 981 node_devices[nid] = kzalloc(sizeof(struct node), GFP_KERNEL); 982 if (!node_devices[nid]) 983 return -ENOMEM; 984 985 error = register_node(node_devices[nid], nid); 986 987 /* link cpu under this node */ 988 for_each_present_cpu(cpu) { 989 if (cpu_to_node(cpu) == nid) 990 register_cpu_under_node(cpu, nid); 991 } 992 993 INIT_LIST_HEAD(&node_devices[nid]->access_list); 994 /* initialize work queue for memory hot plug */ 995 init_node_hugetlb_work(nid); 996 node_init_caches(nid); 997 998 return error; 999 } 1000 1001 void unregister_one_node(int nid) 1002 { 1003 if (!node_devices[nid]) 1004 return; 1005 1006 unregister_node(node_devices[nid]); 1007 node_devices[nid] = NULL; 1008 } 1009 1010 /* 1011 * node states attributes 1012 */ 1013 1014 struct node_attr { 1015 struct device_attribute attr; 1016 enum node_states state; 1017 }; 1018 1019 static ssize_t show_node_state(struct device *dev, 1020 struct device_attribute *attr, char *buf) 1021 { 1022 struct node_attr *na = container_of(attr, struct node_attr, attr); 1023 1024 return sysfs_emit(buf, "%*pbl\n", 1025 nodemask_pr_args(&node_states[na->state])); 1026 } 1027 1028 #define _NODE_ATTR(name, state) \ 1029 { __ATTR(name, 0444, show_node_state, NULL), state } 1030 1031 static struct node_attr node_state_attr[] = { 1032 [N_POSSIBLE] = _NODE_ATTR(possible, N_POSSIBLE), 1033 [N_ONLINE] = _NODE_ATTR(online, N_ONLINE), 1034 [N_NORMAL_MEMORY] = _NODE_ATTR(has_normal_memory, N_NORMAL_MEMORY), 1035 #ifdef CONFIG_HIGHMEM 1036 [N_HIGH_MEMORY] = _NODE_ATTR(has_high_memory, N_HIGH_MEMORY), 1037 #endif 1038 [N_MEMORY] = _NODE_ATTR(has_memory, N_MEMORY), 1039 [N_CPU] = _NODE_ATTR(has_cpu, N_CPU), 1040 [N_GENERIC_INITIATOR] = _NODE_ATTR(has_generic_initiator, 1041 N_GENERIC_INITIATOR), 1042 }; 1043 1044 static struct attribute *node_state_attrs[] = { 1045 &node_state_attr[N_POSSIBLE].attr.attr, 1046 &node_state_attr[N_ONLINE].attr.attr, 1047 &node_state_attr[N_NORMAL_MEMORY].attr.attr, 1048 #ifdef CONFIG_HIGHMEM 1049 &node_state_attr[N_HIGH_MEMORY].attr.attr, 1050 #endif 1051 &node_state_attr[N_MEMORY].attr.attr, 1052 &node_state_attr[N_CPU].attr.attr, 1053 &node_state_attr[N_GENERIC_INITIATOR].attr.attr, 1054 NULL 1055 }; 1056 1057 static const struct attribute_group memory_root_attr_group = { 1058 .attrs = node_state_attrs, 1059 }; 1060 1061 static const struct attribute_group *cpu_root_attr_groups[] = { 1062 &memory_root_attr_group, 1063 NULL, 1064 }; 1065 1066 #define NODE_CALLBACK_PRI 2 /* lower than SLAB */ 1067 void __init node_dev_init(void) 1068 { 1069 static struct notifier_block node_memory_callback_nb = { 1070 .notifier_call = node_memory_callback, 1071 .priority = NODE_CALLBACK_PRI, 1072 }; 1073 int ret, i; 1074 1075 BUILD_BUG_ON(ARRAY_SIZE(node_state_attr) != NR_NODE_STATES); 1076 BUILD_BUG_ON(ARRAY_SIZE(node_state_attrs)-1 != NR_NODE_STATES); 1077 1078 ret = subsys_system_register(&node_subsys, cpu_root_attr_groups); 1079 if (ret) 1080 panic("%s() failed to register subsystem: %d\n", __func__, ret); 1081 1082 register_hotmemory_notifier(&node_memory_callback_nb); 1083 1084 /* 1085 * Create all node devices, which will properly link the node 1086 * to applicable memory block devices and already created cpu devices. 1087 */ 1088 for_each_online_node(i) { 1089 ret = register_one_node(i); 1090 if (ret) 1091 panic("%s() failed to add node: %d\n", __func__, ret); 1092 } 1093 } 1094