arch/x86/mm/numa.c

   1 /* Common code for 32 and 64-bit NUMA */
   2 #include <linux/kernel.h>
   3 #include <linux/mm.h>
   4 #include <linux/string.h>
   5 #include <linux/init.h>
   6 #include <linux/bootmem.h>
   7 #include <linux/memblock.h>
   8 #include <linux/mmzone.h>
   9 #include <linux/ctype.h>
  10 #include <linux/module.h>
  11 #include <linux/nodemask.h>
  12 #include <linux/sched.h>
  13 #include <linux/topology.h>
  14
  15 #include <asm/e820.h>
  16 #include <asm/proto.h>
  17 #include <asm/dma.h>
  18 #include <asm/acpi.h>
  19 #include <asm/amd_nb.h>
  20
  21 #include "numa_internal.h"
  22
  23 int __initdata numa_off;
  24 nodemask_t numa_nodes_parsed __initdata;
  25
  26 struct pglist_data *node_data[MAX_NUMNODES] __read_mostly;
  27 EXPORT_SYMBOL(node_data);
  28
  29 static struct numa_meminfo numa_meminfo
  30 #ifndef CONFIG_MEMORY_HOTPLUG
  31 __initdata
  32 #endif
  33 ;
  34
  35 static int numa_distance_cnt;
  36 static u8 *numa_distance;
  37
  38 static __init int numa_setup(char *opt)
  39 {
  40         if (!opt)
  41                 return -EINVAL;
  42         if (!strncmp(opt, "off", 3))
  43                 numa_off = 1;
  44 #ifdef CONFIG_NUMA_EMU
  45         if (!strncmp(opt, "fake=", 5))
  46                 numa_emu_cmdline(opt + 5);
  47 #endif
  48 #ifdef CONFIG_ACPI_NUMA
  49         if (!strncmp(opt, "noacpi", 6))
  50                 acpi_numa = -1;
  51 #endif
  52         return 0;
  53 }
  54 early_param("numa", numa_setup);
  55
  56 /*
  57  * apicid, cpu, node mappings
  58  */
  59 s16 __apicid_to_node[MAX_LOCAL_APIC] = {
  60         [0 ... MAX_LOCAL_APIC-1] = NUMA_NO_NODE
  61 };
  62
  63 int __cpuinit numa_cpu_node(int cpu)
  64 {
  65         int apicid = early_per_cpu(x86_cpu_to_apicid, cpu);
  66
  67         if (apicid != BAD_APICID)
  68                 return __apicid_to_node[apicid];
  69         return NUMA_NO_NODE;
  70 }
  71
  72 cpumask_var_t node_to_cpumask_map[MAX_NUMNODES];
  73 EXPORT_SYMBOL(node_to_cpumask_map);
  74
  75 /*
  76  * Map cpu index to node index
  77  */
  78 DEFINE_EARLY_PER_CPU(int, x86_cpu_to_node_map, NUMA_NO_NODE);
  79 EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_node_map);
  80
  81 void numa_set_node(int cpu, int node)
  82 {
  83         int *cpu_to_node_map = early_per_cpu_ptr(x86_cpu_to_node_map);
  84
  85         /* early setting, no percpu area yet */
  86         if (cpu_to_node_map) {
  87                 cpu_to_node_map[cpu] = node;
  88                 return;
  89         }
  90
  91 #ifdef CONFIG_DEBUG_PER_CPU_MAPS
  92         if (cpu >= nr_cpu_ids || !cpu_possible(cpu)) {
  93                 printk(KERN_ERR "numa_set_node: invalid cpu# (%d)\n", cpu);
  94                 dump_stack();
  95                 return;
  96         }
  97 #endif
  98         per_cpu(x86_cpu_to_node_map, cpu) = node;
  99
 100         set_cpu_numa_node(cpu, node);
 101 }
 102
 103 void numa_clear_node(int cpu)
 104 {
 105         numa_set_node(cpu, NUMA_NO_NODE);
 106 }
 107
 108 /*
 109  * Allocate node_to_cpumask_map based on number of available nodes
 110  * Requires node_possible_map to be valid.
 111  *
 112  * Note: cpumask_of_node() is not valid until after this is done.
 113  * (Use CONFIG_DEBUG_PER_CPU_MAPS to check this.)
 114  */
 115 void __init setup_node_to_cpumask_map(void)
 116 {
 117         unsigned int node, num = 0;
 118
 119         /* setup nr_node_ids if not done yet */
 120         if (nr_node_ids == MAX_NUMNODES) {
 121                 for_each_node_mask(node, node_possible_map)
 122                         num = node;
 123                 nr_node_ids = num + 1;
 124         }
 125
 126         /* allocate the map */
 127         for (node = 0; node < nr_node_ids; node++)
 128                 alloc_bootmem_cpumask_var(&node_to_cpumask_map[node]);
 129
 130         /* cpumask_of_node() will now work */
 131         pr_debug("Node to cpumask map for %d nodes\n", nr_node_ids);
 132 }
 133
 134 static int __init numa_add_memblk_to(int nid, u64 start, u64 end,
 135                                      struct numa_meminfo *mi)
 136 {
 137         /* ignore zero length blks */
 138         if (start == end)
 139                 return 0;
 140
 141         /* whine about and ignore invalid blks */
 142         if (start > end || nid < 0 || nid >= MAX_NUMNODES) {
 143                 pr_warning("NUMA: Warning: invalid memblk node %d [mem %#010Lx-%#010Lx]\n",
 144                            nid, start, end - 1);
 145                 return 0;
 146         }
 147
 148         if (mi->nr_blks >= NR_NODE_MEMBLKS) {
 149                 pr_err("NUMA: too many memblk ranges\n");
 150                 return -EINVAL;
 151         }
 152
 153         mi->blk[mi->nr_blks].start = start;
 154         mi->blk[mi->nr_blks].end = end;
 155         mi->blk[mi->nr_blks].nid = nid;
 156         mi->nr_blks++;
 157         return 0;
 158 }
 159
 160 /**
 161  * numa_remove_memblk_from - Remove one numa_memblk from a numa_meminfo
 162  * @idx: Index of memblk to remove
 163  * @mi: numa_meminfo to remove memblk from
 164  *
 165  * Remove @idx'th numa_memblk from @mi by shifting @mi->blk[] and
 166  * decrementing @mi->nr_blks.
 167  */
 168 void __init numa_remove_memblk_from(int idx, struct numa_meminfo *mi)
 169 {
 170         mi->nr_blks--;
 171         memmove(&mi->blk[idx], &mi->blk[idx + 1],
 172                 (mi->nr_blks - idx) * sizeof(mi->blk[0]));
 173 }
 174
 175 /**
 176  * numa_add_memblk - Add one numa_memblk to numa_meminfo
 177  * @nid: NUMA node ID of the new memblk
 178  * @start: Start address of the new memblk
 179  * @end: End address of the new memblk
 180  *
 181  * Add a new memblk to the default numa_meminfo.
 182  *
 183  * RETURNS:
 184  * 0 on success, -errno on failure.
 185  */
 186 int __init numa_add_memblk(int nid, u64 start, u64 end)
 187 {
 188         return numa_add_memblk_to(nid, start, end, &numa_meminfo);
 189 }
 190
 191 /* Initialize NODE_DATA for a node on the local memory */
 192 static void __init setup_node_data(int nid, u64 start, u64 end)
 193 {
 194         const size_t nd_size = roundup(sizeof(pg_data_t), PAGE_SIZE);
 195         u64 nd_pa;
 196         void *nd;
 197         int tnid;
 198
 199         /*
 200          * Don't confuse VM with a node that doesn't have the
 201          * minimum amount of memory:
 202          */
 203         if (end && (end - start) < NODE_MIN_SIZE)
 204                 return;
 205
 206         start = roundup(start, ZONE_ALIGN);
 207
 208         printk(KERN_INFO "Initmem setup node %d [mem %#010Lx-%#010Lx]\n",
 209                nid, start, end - 1);
 210
 211         /*
 212          * Allocate node data.  Try node-local memory and then any node.
 213          * Never allocate in DMA zone.
 214          */
 215         nd_pa = memblock_alloc_nid(nd_size, SMP_CACHE_BYTES, nid);
 216         if (!nd_pa) {
 217                 pr_err("Cannot find %zu bytes in node %d\n",
 218                        nd_size, nid);
 219                 return;
 220         }
 221         nd = __va(nd_pa);
 222
 223         /* report and initialize */
 224         printk(KERN_INFO "  NODE_DATA [mem %#010Lx-%#010Lx]\n",
 225                nd_pa, nd_pa + nd_size - 1);
 226         tnid = early_pfn_to_nid(nd_pa >> PAGE_SHIFT);
 227         if (tnid != nid)
 228                 printk(KERN_INFO "    NODE_DATA(%d) on node %d\n", nid, tnid);
 229
 230         node_data[nid] = nd;
 231         memset(NODE_DATA(nid), 0, sizeof(pg_data_t));
 232         NODE_DATA(nid)->node_id = nid;
 233         NODE_DATA(nid)->node_start_pfn = start >> PAGE_SHIFT;
 234         NODE_DATA(nid)->node_spanned_pages = (end - start) >> PAGE_SHIFT;
 235
 236         node_set_online(nid);
 237 }
 238
 239 /**
 240  * numa_cleanup_meminfo - Cleanup a numa_meminfo
 241  * @mi: numa_meminfo to clean up
 242  *
 243  * Sanitize @mi by merging and removing unncessary memblks.  Also check for
 244  * conflicts and clear unused memblks.
 245  *
 246  * RETURNS:
 247  * 0 on success, -errno on failure.
 248  */
 249 int __init numa_cleanup_meminfo(struct numa_meminfo *mi)
 250 {
 251         const u64 low = 0;
 252         const u64 high = PFN_PHYS(max_pfn);
 253         int i, j, k;
 254
 255         /* first, trim all entries */
 256         for (i = 0; i < mi->nr_blks; i++) {
 257                 struct numa_memblk *bi = &mi->blk[i];
 258
 259                 /* make sure all blocks are inside the limits */
 260                 bi->start = max(bi->start, low);
 261                 bi->end = min(bi->end, high);
 262
 263                 /* and there's no empty block */
 264                 if (bi->start >= bi->end)
 265                         numa_remove_memblk_from(i--, mi);
 266         }
 267
 268         /* merge neighboring / overlapping entries */
 269         for (i = 0; i < mi->nr_blks; i++) {
 270                 struct numa_memblk *bi = &mi->blk[i];
 271
 272                 for (j = i + 1; j < mi->nr_blks; j++) {
 273                         struct numa_memblk *bj = &mi->blk[j];
 274                         u64 start, end;
 275
 276                         /*
 277                          * See whether there are overlapping blocks.  Whine
 278                          * about but allow overlaps of the same nid.  They
 279                          * will be merged below.
 280                          */
 281                         if (bi->end > bj->start && bi->start < bj->end) {
 282                                 if (bi->nid != bj->nid) {
 283                                         pr_err("NUMA: node %d [mem %#010Lx-%#010Lx] overlaps with node %d [mem %#010Lx-%#010Lx]\n",
 284                                                bi->nid, bi->start, bi->end - 1,
 285                                                bj->nid, bj->start, bj->end - 1);
 286                                         return -EINVAL;
 287                                 }
 288                                 pr_warning("NUMA: Warning: node %d [mem %#010Lx-%#010Lx] overlaps with itself [mem %#010Lx-%#010Lx]\n",
 289                                            bi->nid, bi->start, bi->end - 1,
 290                                            bj->start, bj->end - 1);
 291                         }
 292
 293                         /*
 294                          * Join together blocks on the same node, holes
 295                          * between which don't overlap with memory on other
 296                          * nodes.
 297                          */
 298                         if (bi->nid != bj->nid)
 299                                 continue;
 300                         start = min(bi->start, bj->start);
 301                         end = max(bi->end, bj->end);
 302                         for (k = 0; k < mi->nr_blks; k++) {
 303                                 struct numa_memblk *bk = &mi->blk[k];
 304
 305                                 if (bi->nid == bk->nid)
 306                                         continue;
 307                                 if (start < bk->end && end > bk->start)
 308                                         break;
 309                         }
 310                         if (k < mi->nr_blks)
 311                                 continue;
 312                         printk(KERN_INFO "NUMA: Node %d [mem %#010Lx-%#010Lx] + [mem %#010Lx-%#010Lx] -> [mem %#010Lx-%#010Lx]\n",
 313                                bi->nid, bi->start, bi->end - 1, bj->start,
 314                                bj->end - 1, start, end - 1);
 315                         bi->start = start;
 316                         bi->end = end;
 317                         numa_remove_memblk_from(j--, mi);
 318                 }
 319         }
 320
 321         /* clear unused ones */
 322         for (i = mi->nr_blks; i < ARRAY_SIZE(mi->blk); i++) {
 323                 mi->blk[i].start = mi->blk[i].end = 0;
 324                 mi->blk[i].nid = NUMA_NO_NODE;
 325         }
 326
 327         return 0;
 328 }
 329
 330 /*
 331  * Set nodes, which have memory in @mi, in *@nodemask.
 332  */
 333 static void __init numa_nodemask_from_meminfo(nodemask_t *nodemask,
 334                                               const struct numa_meminfo *mi)
 335 {
 336         int i;
 337
 338         for (i = 0; i < ARRAY_SIZE(mi->blk); i++)
 339                 if (mi->blk[i].start != mi->blk[i].end &&
 340                     mi->blk[i].nid != NUMA_NO_NODE)
 341                         node_set(mi->blk[i].nid, *nodemask);
 342 }
 343
 344 /**
 345  * numa_reset_distance - Reset NUMA distance table
 346  *
 347  * The current table is freed.  The next numa_set_distance() call will
 348  * create a new one.
 349  */
 350 void __init numa_reset_distance(void)
 351 {
 352         size_t size = numa_distance_cnt * numa_distance_cnt * sizeof(numa_distance[0]);
 353
 354         /* numa_distance could be 1LU marking allocation failure, test cnt */
 355         if (numa_distance_cnt)
 356                 memblock_free(__pa(numa_distance), size);
 357         numa_distance_cnt = 0;
 358         numa_distance = NULL;   /* enable table creation */
 359 }
 360
 361 static int __init numa_alloc_distance(void)
 362 {
 363         nodemask_t nodes_parsed;
 364         size_t size;
 365         int i, j, cnt = 0;
 366         u64 phys;
 367
 368         /* size the new table and allocate it */
 369         nodes_parsed = numa_nodes_parsed;
 370         numa_nodemask_from_meminfo(&nodes_parsed, &numa_meminfo);
 371
 372         for_each_node_mask(i, nodes_parsed)
 373                 cnt = i;
 374         cnt++;
 375         size = cnt * cnt * sizeof(numa_distance[0]);
 376
 377         phys = memblock_find_in_range(0, PFN_PHYS(max_pfn_mapped),
 378                                       size, PAGE_SIZE);
 379         if (!phys) {
 380                 pr_warning("NUMA: Warning: can't allocate distance table!\n");
 381                 /* don't retry until explicitly reset */
 382                 numa_distance = (void *)1LU;
 383                 return -ENOMEM;
 384         }
 385         memblock_reserve(phys, size);
 386
 387         numa_distance = __va(phys);
 388         numa_distance_cnt = cnt;
 389
 390         /* fill with the default distances */
 391         for (i = 0; i < cnt; i++)
 392                 for (j = 0; j < cnt; j++)
 393                         numa_distance[i * cnt + j] = i == j ?
 394                                 LOCAL_DISTANCE : REMOTE_DISTANCE;
 395         printk(KERN_DEBUG "NUMA: Initialized distance table, cnt=%d\n", cnt);
 396
 397         return 0;
 398 }
 399
 400 /**
 401  * numa_set_distance - Set NUMA distance from one NUMA to another
 402  * @from: the 'from' node to set distance
 403  * @to: the 'to'  node to set distance
 404  * @distance: NUMA distance
 405  *
 406  * Set the distance from node @from to @to to @distance.  If distance table
 407  * doesn't exist, one which is large enough to accommodate all the currently
 408  * known nodes will be created.
 409  *
 410  * If such table cannot be allocated, a warning is printed and further
 411  * calls are ignored until the distance table is reset with
 412  * numa_reset_distance().
 413  *
 414  * If @from or @to is higher than the highest known node or lower than zero
 415  * at the time of table creation or @distance doesn't make sense, the call
 416  * is ignored.
 417  * This is to allow simplification of specific NUMA config implementations.
 418  */
 419 void __init numa_set_distance(int from, int to, int distance)
 420 {
 421         if (!numa_distance && numa_alloc_distance() < 0)
 422                 return;
 423
 424         if (from >= numa_distance_cnt || to >= numa_distance_cnt ||
 425                         from < 0 || to < 0) {
 426                 pr_warn_once("NUMA: Warning: node ids are out of bound, from=%d to=%d distance=%d\n",
 427                             from, to, distance);
 428                 return;
 429         }
 430
 431         if ((u8)distance != distance ||
 432             (from == to && distance != LOCAL_DISTANCE)) {
 433                 pr_warn_once("NUMA: Warning: invalid distance parameter, from=%d to=%d distance=%d\n",
 434                              from, to, distance);
 435                 return;
 436         }
 437
 438         numa_distance[from * numa_distance_cnt + to] = distance;
 439 }
 440
 441 int __node_distance(int from, int to)
 442 {
 443         if (from >= numa_distance_cnt || to >= numa_distance_cnt)
 444                 return from == to ? LOCAL_DISTANCE : REMOTE_DISTANCE;
 445         return numa_distance[from * numa_distance_cnt + to];
 446 }
 447 EXPORT_SYMBOL(__node_distance);
 448
 449 /*
 450  * Sanity check to catch more bad NUMA configurations (they are amazingly
 451  * common).  Make sure the nodes cover all memory.
 452  */
 453 static bool __init numa_meminfo_cover_memory(const struct numa_meminfo *mi)
 454 {
 455         u64 numaram, e820ram;
 456         int i;
 457
 458         numaram = 0;
 459         for (i = 0; i < mi->nr_blks; i++) {
 460                 u64 s = mi->blk[i].start >> PAGE_SHIFT;
 461                 u64 e = mi->blk[i].end >> PAGE_SHIFT;
 462                 numaram += e - s;
 463                 numaram -= __absent_pages_in_range(mi->blk[i].nid, s, e);
 464                 if ((s64)numaram < 0)
 465                         numaram = 0;
 466         }
 467
 468         e820ram = max_pfn - absent_pages_in_range(0, max_pfn);
 469
 470         /* We seem to lose 3 pages somewhere. Allow 1M of slack. */
 471         if ((s64)(e820ram - numaram) >= (1 << (20 - PAGE_SHIFT))) {
 472                 printk(KERN_ERR "NUMA: nodes only cover %LuMB of your %LuMB e820 RAM. Not used.\n",
 473                        (numaram << PAGE_SHIFT) >> 20,
 474                        (e820ram << PAGE_SHIFT) >> 20);
 475                 return false;
 476         }
 477         return true;
 478 }
 479
 480 static int __init numa_register_memblks(struct numa_meminfo *mi)
 481 {
 482         unsigned long uninitialized_var(pfn_align);
 483         int i, nid;
 484
 485         /* Account for nodes with cpus and no memory */
 486         node_possible_map = numa_nodes_parsed;
 487         numa_nodemask_from_meminfo(&node_possible_map, mi);
 488         if (WARN_ON(nodes_empty(node_possible_map)))
 489                 return -EINVAL;
 490
 491         for (i = 0; i < mi->nr_blks; i++) {
 492                 struct numa_memblk *mb = &mi->blk[i];
 493                 memblock_set_node(mb->start, mb->end - mb->start, mb->nid);
 494         }
 495
 496         /*
 497          * If sections array is gonna be used for pfn -> nid mapping, check
 498          * whether its granularity is fine enough.
 499          */
 500 #ifdef NODE_NOT_IN_PAGE_FLAGS
 501         pfn_align = node_map_pfn_alignment();
 502         if (pfn_align && pfn_align < PAGES_PER_SECTION) {
 503                 printk(KERN_WARNING "Node alignment %LuMB < min %LuMB, rejecting NUMA config\n",
 504                        PFN_PHYS(pfn_align) >> 20,
 505                        PFN_PHYS(PAGES_PER_SECTION) >> 20);
 506                 return -EINVAL;
 507         }
 508 #endif
 509         if (!numa_meminfo_cover_memory(mi))
 510                 return -EINVAL;
 511
 512         /* Finally register nodes. */
 513         for_each_node_mask(nid, node_possible_map) {
 514                 u64 start = PFN_PHYS(max_pfn);
 515                 u64 end = 0;
 516
 517                 for (i = 0; i < mi->nr_blks; i++) {
 518                         if (nid != mi->blk[i].nid)
 519                                 continue;
 520                         start = min(mi->blk[i].start, start);
 521                         end = max(mi->blk[i].end, end);
 522                 }
 523
 524                 if (start < end)
 525                         setup_node_data(nid, start, end);
 526         }
 527
 528         /* Dump memblock with node info and return. */
 529         memblock_dump_all();
 530         return 0;
 531 }
 532
 533 /*
 534  * There are unfortunately some poorly designed mainboards around that
 535  * only connect memory to a single CPU. This breaks the 1:1 cpu->node
 536  * mapping. To avoid this fill in the mapping for all possible CPUs,
 537  * as the number of CPUs is not known yet. We round robin the existing
 538  * nodes.
 539  */
 540 static void __init numa_init_array(void)
 541 {
 542         int rr, i;
 543
 544         rr = first_node(node_online_map);
 545         for (i = 0; i < nr_cpu_ids; i++) {
 546                 if (early_cpu_to_node(i) != NUMA_NO_NODE)
 547                         continue;
 548                 numa_set_node(i, rr);
 549                 rr = next_node(rr, node_online_map);
 550                 if (rr == MAX_NUMNODES)
 551                         rr = first_node(node_online_map);
 552         }
 553 }
 554
 555 static int __init numa_init(int (*init_func)(void))
 556 {
 557         int i;
 558         int ret;
 559
 560         for (i = 0; i < MAX_LOCAL_APIC; i++)
 561                 set_apicid_to_node(i, NUMA_NO_NODE);
 562
 563         nodes_clear(numa_nodes_parsed);
 564         nodes_clear(node_possible_map);
 565         nodes_clear(node_online_map);
 566         memset(&numa_meminfo, 0, sizeof(numa_meminfo));
 567         WARN_ON(memblock_set_node(0, ULLONG_MAX, MAX_NUMNODES));
 568         numa_reset_distance();
 569
 570         ret = init_func();
 571         if (ret < 0)
 572                 return ret;
 573         ret = numa_cleanup_meminfo(&numa_meminfo);
 574         if (ret < 0)
 575                 return ret;
 576
 577         numa_emulation(&numa_meminfo, numa_distance_cnt);
 578
 579         ret = numa_register_memblks(&numa_meminfo);
 580         if (ret < 0)
 581                 return ret;
 582
 583         for (i = 0; i < nr_cpu_ids; i++) {
 584                 int nid = early_cpu_to_node(i);
 585
 586                 if (nid == NUMA_NO_NODE)
 587                         continue;
 588                 if (!node_online(nid))
 589                         numa_clear_node(i);
 590         }
 591         numa_init_array();
 592         return 0;
 593 }
 594
 595 /**
 596  * dummy_numa_init - Fallback dummy NUMA init
 597  *
 598  * Used if there's no underlying NUMA architecture, NUMA initialization
 599  * fails, or NUMA is disabled on the command line.
 600  *
 601  * Must online at least one node and add memory blocks that cover all
 602  * allowed memory.  This function must not fail.
 603  */
 604 static int __init dummy_numa_init(void)
 605 {
 606         printk(KERN_INFO "%s\n",
 607                numa_off ? "NUMA turned off" : "No NUMA configuration found");
 608         printk(KERN_INFO "Faking a node at [mem %#018Lx-%#018Lx]\n",
 609                0LLU, PFN_PHYS(max_pfn) - 1);
 610
 611         node_set(0, numa_nodes_parsed);
 612         numa_add_memblk(0, 0, PFN_PHYS(max_pfn));
 613
 614         return 0;
 615 }
 616
 617 /**
 618  * x86_numa_init - Initialize NUMA
 619  *
 620  * Try each configured NUMA initialization method until one succeeds.  The
 621  * last fallback is dummy single node config encomapssing whole memory and
 622  * never fails.
 623  */
 624 void __init x86_numa_init(void)
 625 {
 626         if (!numa_off) {
 627 #ifdef CONFIG_X86_NUMAQ
 628                 if (!numa_init(numaq_numa_init))
 629                         return;
 630 #endif
 631 #ifdef CONFIG_ACPI_NUMA
 632                 if (!numa_init(x86_acpi_numa_init))
 633                         return;
 634 #endif
 635 #ifdef CONFIG_AMD_NUMA
 636                 if (!numa_init(amd_numa_init))
 637                         return;
 638 #endif
 639         }
 640
 641         numa_init(dummy_numa_init);
 642 }
 643
 644 static __init int find_near_online_node(int node)
 645 {
 646         int n, val;
 647         int min_val = INT_MAX;
 648         int best_node = -1;
 649
 650         for_each_online_node(n) {
 651                 val = node_distance(node, n);
 652
 653                 if (val < min_val) {
 654                         min_val = val;
 655                         best_node = n;
 656                 }
 657         }
 658
 659         return best_node;
 660 }
 661
 662 /*
 663  * Setup early cpu_to_node.
 664  *
 665  * Populate cpu_to_node[] only if x86_cpu_to_apicid[],
 666  * and apicid_to_node[] tables have valid entries for a CPU.
 667  * This means we skip cpu_to_node[] initialisation for NUMA
 668  * emulation and faking node case (when running a kernel compiled
 669  * for NUMA on a non NUMA box), which is OK as cpu_to_node[]
 670  * is already initialized in a round robin manner at numa_init_array,
 671  * prior to this call, and this initialization is good enough
 672  * for the fake NUMA cases.
 673  *
 674  * Called before the per_cpu areas are setup.
 675  */
 676 void __init init_cpu_to_node(void)
 677 {
 678         int cpu;
 679         u16 *cpu_to_apicid = early_per_cpu_ptr(x86_cpu_to_apicid);
 680
 681         BUG_ON(cpu_to_apicid == NULL);
 682
 683         for_each_possible_cpu(cpu) {
 684                 int node = numa_cpu_node(cpu);
 685
 686                 if (node == NUMA_NO_NODE)
 687                         continue;
 688                 if (!node_online(node))
 689                         node = find_near_online_node(node);
 690                 numa_set_node(cpu, node);
 691         }
 692 }
 693
 694 #ifndef CONFIG_DEBUG_PER_CPU_MAPS
 695
 696 # ifndef CONFIG_NUMA_EMU
 697 void __cpuinit numa_add_cpu(int cpu)
 698 {
 699         cpumask_set_cpu(cpu, node_to_cpumask_map[early_cpu_to_node(cpu)]);
 700 }
 701
 702 void __cpuinit numa_remove_cpu(int cpu)
 703 {
 704         cpumask_clear_cpu(cpu, node_to_cpumask_map[early_cpu_to_node(cpu)]);
 705 }
 706 # endif /* !CONFIG_NUMA_EMU */
 707
 708 #else   /* !CONFIG_DEBUG_PER_CPU_MAPS */
 709
 710 int __cpu_to_node(int cpu)
 711 {
 712         if (early_per_cpu_ptr(x86_cpu_to_node_map)) {
 713                 printk(KERN_WARNING
 714                         "cpu_to_node(%d): usage too early!\n", cpu);
 715                 dump_stack();
 716                 return early_per_cpu_ptr(x86_cpu_to_node_map)[cpu];
 717         }
 718         return per_cpu(x86_cpu_to_node_map, cpu);
 719 }
 720 EXPORT_SYMBOL(__cpu_to_node);
 721
 722 /*
 723  * Same function as cpu_to_node() but used if called before the
 724  * per_cpu areas are setup.
 725  */
 726 int early_cpu_to_node(int cpu)
 727 {
 728         if (early_per_cpu_ptr(x86_cpu_to_node_map))
 729                 return early_per_cpu_ptr(x86_cpu_to_node_map)[cpu];
 730
 731         if (!cpu_possible(cpu)) {
 732                 printk(KERN_WARNING
 733                         "early_cpu_to_node(%d): no per_cpu area!\n", cpu);
 734                 dump_stack();
 735                 return NUMA_NO_NODE;
 736         }
 737         return per_cpu(x86_cpu_to_node_map, cpu);
 738 }
 739
 740 void debug_cpumask_set_cpu(int cpu, int node, bool enable)
 741 {
 742         struct cpumask *mask;
 743         char buf[64];
 744
 745         if (node == NUMA_NO_NODE) {
 746                 /* early_cpu_to_node() already emits a warning and trace */
 747                 return;
 748         }
 749         mask = node_to_cpumask_map[node];
 750         if (!mask) {
 751                 pr_err("node_to_cpumask_map[%i] NULL\n", node);
 752                 dump_stack();
 753                 return;
 754         }
 755
 756         if (enable)
 757                 cpumask_set_cpu(cpu, mask);
 758         else
 759                 cpumask_clear_cpu(cpu, mask);
 760
 761         cpulist_scnprintf(buf, sizeof(buf), mask);
 762         printk(KERN_DEBUG "%s cpu %d node %d: mask now %s\n",
 763                 enable ? "numa_add_cpu" : "numa_remove_cpu",
 764                 cpu, node, buf);
 765         return;
 766 }
 767
 768 # ifndef CONFIG_NUMA_EMU
 769 static void __cpuinit numa_set_cpumask(int cpu, bool enable)
 770 {
 771         debug_cpumask_set_cpu(cpu, early_cpu_to_node(cpu), enable);
 772 }
 773
 774 void __cpuinit numa_add_cpu(int cpu)
 775 {
 776         numa_set_cpumask(cpu, true);
 777 }
 778
 779 void __cpuinit numa_remove_cpu(int cpu)
 780 {
 781         numa_set_cpumask(cpu, false);
 782 }
 783 # endif /* !CONFIG_NUMA_EMU */
 784
 785 /*
 786  * Returns a pointer to the bitmask of CPUs on Node 'node'.
 787  */
 788 const struct cpumask *cpumask_of_node(int node)
 789 {
 790         if (node >= nr_node_ids) {
 791                 printk(KERN_WARNING
 792                         "cpumask_of_node(%d): node > nr_node_ids(%d)\n",
 793                         node, nr_node_ids);
 794                 dump_stack();
 795                 return cpu_none_mask;
 796         }
 797         if (node_to_cpumask_map[node] == NULL) {
 798                 printk(KERN_WARNING
 799                         "cpumask_of_node(%d): no node_to_cpumask_map!\n",
 800                         node);
 801                 dump_stack();
 802                 return cpu_online_mask;
 803         }
 804         return node_to_cpumask_map[node];
 805 }
 806 EXPORT_SYMBOL(cpumask_of_node);
 807
 808 #endif  /* !CONFIG_DEBUG_PER_CPU_MAPS */
 809
 810 #ifdef CONFIG_MEMORY_HOTPLUG
 811 int memory_add_physaddr_to_nid(u64 start)
 812 {
 813         struct numa_meminfo *mi = &numa_meminfo;
 814         int nid = mi->blk[0].nid;
 815         int i;
 816
 817         for (i = 0; i < mi->nr_blks; i++)
 818                 if (mi->blk[i].start <= start && mi->blk[i].end > start)
 819                         nid = mi->blk[i].nid;
 820         return nid;
 821 }
 822 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
 823 #endif