arch/arm64/mm/numa.c

   1 /*
   2  * NUMA support, based on the x86 implementation.
   3  *
   4  * Copyright (C) 2015 Cavium Inc.
   5  * Author: Ganapatrao Kulkarni <gkulkarni@cavium.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #define pr_fmt(fmt) "NUMA: " fmt
  21
  22 #include <linux/acpi.h>
  23 #include <linux/bootmem.h>
  24 #include <linux/memblock.h>
  25 #include <linux/module.h>
  26 #include <linux/of.h>
  27
  28 #include <asm/acpi.h>
  29 #include <asm/sections.h>
  30
  31 struct pglist_data *node_data[MAX_NUMNODES] __read_mostly;
  32 EXPORT_SYMBOL(node_data);
  33 nodemask_t numa_nodes_parsed __initdata;
  34 static int cpu_to_node_map[NR_CPUS] = { [0 ... NR_CPUS-1] = NUMA_NO_NODE };
  35
  36 static int numa_distance_cnt;
  37 static u8 *numa_distance;
  38 bool numa_off;
  39
  40 static __init int numa_parse_early_param(char *opt)
  41 {
  42         if (!opt)
  43                 return -EINVAL;
  44         if (!strncmp(opt, "off", 3))
  45                 numa_off = true;
  46
  47         return 0;
  48 }
  49 early_param("numa", numa_parse_early_param);
  50
  51 cpumask_var_t node_to_cpumask_map[MAX_NUMNODES];
  52 EXPORT_SYMBOL(node_to_cpumask_map);
  53
  54 #ifdef CONFIG_DEBUG_PER_CPU_MAPS
  55
  56 /*
  57  * Returns a pointer to the bitmask of CPUs on Node 'node'.
  58  */
  59 const struct cpumask *cpumask_of_node(int node)
  60 {
  61         if (WARN_ON(node >= nr_node_ids))
  62                 return cpu_none_mask;
  63
  64         if (WARN_ON(node_to_cpumask_map[node] == NULL))
  65                 return cpu_online_mask;
  66
  67         return node_to_cpumask_map[node];
  68 }
  69 EXPORT_SYMBOL(cpumask_of_node);
  70
  71 #endif
  72
  73 static void map_cpu_to_node(unsigned int cpu, int nid)
  74 {
  75         set_cpu_numa_node(cpu, nid);
  76         if (nid >= 0)
  77                 cpumask_set_cpu(cpu, node_to_cpumask_map[nid]);
  78 }
  79
  80 void numa_clear_node(unsigned int cpu)
  81 {
  82         int nid = cpu_to_node(cpu);
  83
  84         if (nid >= 0)
  85                 cpumask_clear_cpu(cpu, node_to_cpumask_map[nid]);
  86         set_cpu_numa_node(cpu, NUMA_NO_NODE);
  87 }
  88
  89 /*
  90  * Allocate node_to_cpumask_map based on number of available nodes
  91  * Requires node_possible_map to be valid.
  92  *
  93  * Note: cpumask_of_node() is not valid until after this is done.
  94  * (Use CONFIG_DEBUG_PER_CPU_MAPS to check this.)
  95  */
  96 static void __init setup_node_to_cpumask_map(void)
  97 {
  98         int node;
  99
 100         /* setup nr_node_ids if not done yet */
 101         if (nr_node_ids == MAX_NUMNODES)
 102                 setup_nr_node_ids();
 103
 104         /* allocate and clear the mapping */
 105         for (node = 0; node < nr_node_ids; node++) {
 106                 alloc_bootmem_cpumask_var(&node_to_cpumask_map[node]);
 107                 cpumask_clear(node_to_cpumask_map[node]);
 108         }
 109
 110         /* cpumask_of_node() will now work */
 111         pr_debug("Node to cpumask map for %d nodes\n", nr_node_ids);
 112 }
 113
 114 /*
 115  *  Set the cpu to node and mem mapping
 116  */
 117 void numa_store_cpu_info(unsigned int cpu)
 118 {
 119         map_cpu_to_node(cpu, cpu_to_node_map[cpu]);
 120 }
 121
 122 void __init early_map_cpu_to_node(unsigned int cpu, int nid)
 123 {
 124         /* fallback to node 0 */
 125         if (nid < 0 || nid >= MAX_NUMNODES || numa_off)
 126                 nid = 0;
 127
 128         cpu_to_node_map[cpu] = nid;
 129
 130         /*
 131          * We should set the numa node of cpu0 as soon as possible, because it
 132          * has already been set up online before. cpu_to_node(0) will soon be
 133          * called.
 134          */
 135         if (!cpu)
 136                 set_cpu_numa_node(cpu, nid);
 137 }
 138
 139 #ifdef CONFIG_HAVE_SETUP_PER_CPU_AREA
 140 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
 141 EXPORT_SYMBOL(__per_cpu_offset);
 142
 143 static int __init early_cpu_to_node(int cpu)
 144 {
 145         return cpu_to_node_map[cpu];
 146 }
 147
 148 static int __init pcpu_cpu_distance(unsigned int from, unsigned int to)
 149 {
 150         return node_distance(early_cpu_to_node(from), early_cpu_to_node(to));
 151 }
 152
 153 static void * __init pcpu_fc_alloc(unsigned int cpu, size_t size,
 154                                        size_t align)
 155 {
 156         int nid = early_cpu_to_node(cpu);
 157
 158         return  memblock_virt_alloc_try_nid(size, align,
 159                         __pa(MAX_DMA_ADDRESS), MEMBLOCK_ALLOC_ACCESSIBLE, nid);
 160 }
 161
 162 static void __init pcpu_fc_free(void *ptr, size_t size)
 163 {
 164         memblock_free_early(__pa(ptr), size);
 165 }
 166
 167 void __init setup_per_cpu_areas(void)
 168 {
 169         unsigned long delta;
 170         unsigned int cpu;
 171         int rc;
 172
 173         /*
 174          * Always reserve area for module percpu variables.  That's
 175          * what the legacy allocator did.
 176          */
 177         rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE,
 178                                     PERCPU_DYNAMIC_RESERVE, PAGE_SIZE,
 179                                     pcpu_cpu_distance,
 180                                     pcpu_fc_alloc, pcpu_fc_free);
 181         if (rc < 0)
 182                 panic("Failed to initialize percpu areas.");
 183
 184         delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
 185         for_each_possible_cpu(cpu)
 186                 __per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];
 187 }
 188 #endif
 189
 190 /**
 191  * numa_add_memblk - Set node id to memblk
 192  * @nid: NUMA node ID of the new memblk
 193  * @start: Start address of the new memblk
 194  * @end:  End address of the new memblk
 195  *
 196  * RETURNS:
 197  * 0 on success, -errno on failure.
 198  */
 199 int __init numa_add_memblk(int nid, u64 start, u64 end)
 200 {
 201         int ret;
 202
 203         ret = memblock_set_node(start, (end - start), &memblock.memory, nid);
 204         if (ret < 0) {
 205                 pr_err("memblock [0x%llx - 0x%llx] failed to add on node %d\n",
 206                         start, (end - 1), nid);
 207                 return ret;
 208         }
 209
 210         node_set(nid, numa_nodes_parsed);
 211         pr_info("Adding memblock [0x%llx - 0x%llx] on node %d\n",
 212                         start, (end - 1), nid);
 213         return ret;
 214 }
 215
 216 /**
 217  * Initialize NODE_DATA for a node on the local memory
 218  */
 219 static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn)
 220 {
 221         const size_t nd_size = roundup(sizeof(pg_data_t), SMP_CACHE_BYTES);
 222         u64 nd_pa;
 223         void *nd;
 224         int tnid;
 225
 226         if (start_pfn < end_pfn)
 227                 pr_info("Initmem setup node %d [mem %#010Lx-%#010Lx]\n", nid,
 228                         start_pfn << PAGE_SHIFT, (end_pfn << PAGE_SHIFT) - 1);
 229         else
 230                 pr_info("Initmem setup node %d [<memory-less node>]\n", nid);
 231
 232         nd_pa = memblock_alloc_try_nid(nd_size, SMP_CACHE_BYTES, nid);
 233         nd = __va(nd_pa);
 234
 235         /* report and initialize */
 236         pr_info("NODE_DATA [mem %#010Lx-%#010Lx]\n",
 237                 nd_pa, nd_pa + nd_size - 1);
 238         tnid = early_pfn_to_nid(nd_pa >> PAGE_SHIFT);
 239         if (tnid != nid)
 240                 pr_info("NODE_DATA(%d) on node %d\n", nid, tnid);
 241
 242         node_data[nid] = nd;
 243         memset(NODE_DATA(nid), 0, sizeof(pg_data_t));
 244         NODE_DATA(nid)->node_id = nid;
 245         NODE_DATA(nid)->node_start_pfn = start_pfn;
 246         NODE_DATA(nid)->node_spanned_pages = end_pfn - start_pfn;
 247 }
 248
 249 /**
 250  * numa_free_distance
 251  *
 252  * The current table is freed.
 253  */
 254 void __init numa_free_distance(void)
 255 {
 256         size_t size;
 257
 258         if (!numa_distance)
 259                 return;
 260
 261         size = numa_distance_cnt * numa_distance_cnt *
 262                 sizeof(numa_distance[0]);
 263
 264         memblock_free(__pa(numa_distance), size);
 265         numa_distance_cnt = 0;
 266         numa_distance = NULL;
 267 }
 268
 269 /**
 270  *
 271  * Create a new NUMA distance table.
 272  *
 273  */
 274 static int __init numa_alloc_distance(void)
 275 {
 276         size_t size;
 277         u64 phys;
 278         int i, j;
 279
 280         size = nr_node_ids * nr_node_ids * sizeof(numa_distance[0]);
 281         phys = memblock_find_in_range(0, PFN_PHYS(max_pfn),
 282                                       size, PAGE_SIZE);
 283         if (WARN_ON(!phys))
 284                 return -ENOMEM;
 285
 286         memblock_reserve(phys, size);
 287
 288         numa_distance = __va(phys);
 289         numa_distance_cnt = nr_node_ids;
 290
 291         /* fill with the default distances */
 292         for (i = 0; i < numa_distance_cnt; i++)
 293                 for (j = 0; j < numa_distance_cnt; j++)
 294                         numa_distance[i * numa_distance_cnt + j] = i == j ?
 295                                 LOCAL_DISTANCE : REMOTE_DISTANCE;
 296
 297         pr_debug("Initialized distance table, cnt=%d\n", numa_distance_cnt);
 298
 299         return 0;
 300 }
 301
 302 /**
 303  * numa_set_distance - Set inter node NUMA distance from node to node.
 304  * @from: the 'from' node to set distance
 305  * @to: the 'to'  node to set distance
 306  * @distance: NUMA distance
 307  *
 308  * Set the distance from node @from to @to to @distance.
 309  * If distance table doesn't exist, a warning is printed.
 310  *
 311  * If @from or @to is higher than the highest known node or lower than zero
 312  * or @distance doesn't make sense, the call is ignored.
 313  *
 314  */
 315 void __init numa_set_distance(int from, int to, int distance)
 316 {
 317         if (!numa_distance) {
 318                 pr_warn_once("Warning: distance table not allocated yet\n");
 319                 return;
 320         }
 321
 322         if (from >= numa_distance_cnt || to >= numa_distance_cnt ||
 323                         from < 0 || to < 0) {
 324                 pr_warn_once("Warning: node ids are out of bound, from=%d to=%d distance=%d\n",
 325                             from, to, distance);
 326                 return;
 327         }
 328
 329         if ((u8)distance != distance ||
 330             (from == to && distance != LOCAL_DISTANCE)) {
 331                 pr_warn_once("Warning: invalid distance parameter, from=%d to=%d distance=%d\n",
 332                              from, to, distance);
 333                 return;
 334         }
 335
 336         numa_distance[from * numa_distance_cnt + to] = distance;
 337 }
 338
 339 /**
 340  * Return NUMA distance @from to @to
 341  */
 342 int __node_distance(int from, int to)
 343 {
 344         if (from >= numa_distance_cnt || to >= numa_distance_cnt)
 345                 return from == to ? LOCAL_DISTANCE : REMOTE_DISTANCE;
 346         return numa_distance[from * numa_distance_cnt + to];
 347 }
 348 EXPORT_SYMBOL(__node_distance);
 349
 350 static int __init numa_register_nodes(void)
 351 {
 352         int nid;
 353         struct memblock_region *mblk;
 354
 355         /* Check that valid nid is set to memblks */
 356         for_each_memblock(memory, mblk)
 357                 if (mblk->nid == NUMA_NO_NODE || mblk->nid >= MAX_NUMNODES) {
 358                         pr_warn("Warning: invalid memblk node %d [mem %#010Lx-%#010Lx]\n",
 359                                 mblk->nid, mblk->base,
 360                                 mblk->base + mblk->size - 1);
 361                         return -EINVAL;
 362                 }
 363
 364         /* Finally register nodes. */
 365         for_each_node_mask(nid, numa_nodes_parsed) {
 366                 unsigned long start_pfn, end_pfn;
 367
 368                 get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
 369                 setup_node_data(nid, start_pfn, end_pfn);
 370                 node_set_online(nid);
 371         }
 372
 373         /* Setup online nodes to actual nodes*/
 374         node_possible_map = numa_nodes_parsed;
 375
 376         return 0;
 377 }
 378
 379 static int __init numa_init(int (*init_func)(void))
 380 {
 381         int ret;
 382
 383         nodes_clear(numa_nodes_parsed);
 384         nodes_clear(node_possible_map);
 385         nodes_clear(node_online_map);
 386         numa_free_distance();
 387
 388         ret = numa_alloc_distance();
 389         if (ret < 0)
 390                 return ret;
 391
 392         ret = init_func();
 393         if (ret < 0)
 394                 return ret;
 395
 396         if (nodes_empty(numa_nodes_parsed)) {
 397                 pr_info("No NUMA configuration found\n");
 398                 return -EINVAL;
 399         }
 400
 401         ret = numa_register_nodes();
 402         if (ret < 0)
 403                 return ret;
 404
 405         setup_node_to_cpumask_map();
 406
 407         return 0;
 408 }
 409
 410 /**
 411  * dummy_numa_init - Fallback dummy NUMA init
 412  *
 413  * Used if there's no underlying NUMA architecture, NUMA initialization
 414  * fails, or NUMA is disabled on the command line.
 415  *
 416  * Must online at least one node (node 0) and add memory blocks that cover all
 417  * allowed memory. It is unlikely that this function fails.
 418  */
 419 static int __init dummy_numa_init(void)
 420 {
 421         int ret;
 422         struct memblock_region *mblk;
 423
 424         if (numa_off)
 425                 pr_info("NUMA disabled\n"); /* Forced off on command line. */
 426         pr_info("Faking a node at [mem %#018Lx-%#018Lx]\n",
 427                 0LLU, PFN_PHYS(max_pfn) - 1);
 428
 429         for_each_memblock(memory, mblk) {
 430                 ret = numa_add_memblk(0, mblk->base, mblk->base + mblk->size);
 431                 if (!ret)
 432                         continue;
 433
 434                 pr_err("NUMA init failed\n");
 435                 return ret;
 436         }
 437
 438         numa_off = true;
 439         return 0;
 440 }
 441
 442 /**
 443  * arm64_numa_init - Initialize NUMA
 444  *
 445  * Try each configured NUMA initialization method until one succeeds.  The
 446  * last fallback is dummy single node config encomapssing whole memory.
 447  */
 448 void __init arm64_numa_init(void)
 449 {
 450         if (!numa_off) {
 451                 if (!acpi_disabled && !numa_init(arm64_acpi_numa_init))
 452                         return;
 453                 if (acpi_disabled && !numa_init(of_numa_init))
 454                         return;
 455         }
 456
 457         numa_init(dummy_numa_init);
 458 }