linux/drivers/base/arch_numa.c
<<
>>
Prefs
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * NUMA support, based on the x86 implementation.
   4 *
   5 * Copyright (C) 2015 Cavium Inc.
   6 * Author: Ganapatrao Kulkarni <gkulkarni@cavium.com>
   7 */
   8
   9#define pr_fmt(fmt) "NUMA: " fmt
  10
  11#include <linux/acpi.h>
  12#include <linux/memblock.h>
  13#include <linux/module.h>
  14#include <linux/of.h>
  15
  16#include <asm/sections.h>
  17
  18struct pglist_data *node_data[MAX_NUMNODES] __read_mostly;
  19EXPORT_SYMBOL(node_data);
  20nodemask_t numa_nodes_parsed __initdata;
  21static int cpu_to_node_map[NR_CPUS] = { [0 ... NR_CPUS-1] = NUMA_NO_NODE };
  22
  23static int numa_distance_cnt;
  24static u8 *numa_distance;
  25bool numa_off;
  26
  27static __init int numa_parse_early_param(char *opt)
  28{
  29        if (!opt)
  30                return -EINVAL;
  31        if (str_has_prefix(opt, "off"))
  32                numa_off = true;
  33
  34        return 0;
  35}
  36early_param("numa", numa_parse_early_param);
  37
  38cpumask_var_t node_to_cpumask_map[MAX_NUMNODES];
  39EXPORT_SYMBOL(node_to_cpumask_map);
  40
  41#ifdef CONFIG_DEBUG_PER_CPU_MAPS
  42
  43/*
  44 * Returns a pointer to the bitmask of CPUs on Node 'node'.
  45 */
  46const struct cpumask *cpumask_of_node(int node)
  47{
  48
  49        if (node == NUMA_NO_NODE)
  50                return cpu_all_mask;
  51
  52        if (WARN_ON(node < 0 || node >= nr_node_ids))
  53                return cpu_none_mask;
  54
  55        if (WARN_ON(node_to_cpumask_map[node] == NULL))
  56                return cpu_online_mask;
  57
  58        return node_to_cpumask_map[node];
  59}
  60EXPORT_SYMBOL(cpumask_of_node);
  61
  62#endif
  63
  64static void numa_update_cpu(unsigned int cpu, bool remove)
  65{
  66        int nid = cpu_to_node(cpu);
  67
  68        if (nid == NUMA_NO_NODE)
  69                return;
  70
  71        if (remove)
  72                cpumask_clear_cpu(cpu, node_to_cpumask_map[nid]);
  73        else
  74                cpumask_set_cpu(cpu, node_to_cpumask_map[nid]);
  75}
  76
  77void numa_add_cpu(unsigned int cpu)
  78{
  79        numa_update_cpu(cpu, false);
  80}
  81
  82void numa_remove_cpu(unsigned int cpu)
  83{
  84        numa_update_cpu(cpu, true);
  85}
  86
  87void numa_clear_node(unsigned int cpu)
  88{
  89        numa_remove_cpu(cpu);
  90        set_cpu_numa_node(cpu, NUMA_NO_NODE);
  91}
  92
  93/*
  94 * Allocate node_to_cpumask_map based on number of available nodes
  95 * Requires node_possible_map to be valid.
  96 *
  97 * Note: cpumask_of_node() is not valid until after this is done.
  98 * (Use CONFIG_DEBUG_PER_CPU_MAPS to check this.)
  99 */
 100static void __init setup_node_to_cpumask_map(void)
 101{
 102        int node;
 103
 104        /* setup nr_node_ids if not done yet */
 105        if (nr_node_ids == MAX_NUMNODES)
 106                setup_nr_node_ids();
 107
 108        /* allocate and clear the mapping */
 109        for (node = 0; node < nr_node_ids; node++) {
 110                alloc_bootmem_cpumask_var(&node_to_cpumask_map[node]);
 111                cpumask_clear(node_to_cpumask_map[node]);
 112        }
 113
 114        /* cpumask_of_node() will now work */
 115        pr_debug("Node to cpumask map for %u nodes\n", nr_node_ids);
 116}
 117
 118/*
 119 * Set the cpu to node and mem mapping
 120 */
 121void numa_store_cpu_info(unsigned int cpu)
 122{
 123        set_cpu_numa_node(cpu, cpu_to_node_map[cpu]);
 124}
 125
 126void __init early_map_cpu_to_node(unsigned int cpu, int nid)
 127{
 128        /* fallback to node 0 */
 129        if (nid < 0 || nid >= MAX_NUMNODES || numa_off)
 130                nid = 0;
 131
 132        cpu_to_node_map[cpu] = nid;
 133
 134        /*
 135         * We should set the numa node of cpu0 as soon as possible, because it
 136         * has already been set up online before. cpu_to_node(0) will soon be
 137         * called.
 138         */
 139        if (!cpu)
 140                set_cpu_numa_node(cpu, nid);
 141}
 142
 143#ifdef CONFIG_HAVE_SETUP_PER_CPU_AREA
 144unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
 145EXPORT_SYMBOL(__per_cpu_offset);
 146
 147static int __init early_cpu_to_node(int cpu)
 148{
 149        return cpu_to_node_map[cpu];
 150}
 151
 152static int __init pcpu_cpu_distance(unsigned int from, unsigned int to)
 153{
 154        return node_distance(early_cpu_to_node(from), early_cpu_to_node(to));
 155}
 156
 157static void * __init pcpu_fc_alloc(unsigned int cpu, size_t size,
 158                                       size_t align)
 159{
 160        int nid = early_cpu_to_node(cpu);
 161
 162        return  memblock_alloc_try_nid(size, align,
 163                        __pa(MAX_DMA_ADDRESS), MEMBLOCK_ALLOC_ACCESSIBLE, nid);
 164}
 165
 166static void __init pcpu_fc_free(void *ptr, size_t size)
 167{
 168        memblock_free_early(__pa(ptr), size);
 169}
 170
 171void __init setup_per_cpu_areas(void)
 172{
 173        unsigned long delta;
 174        unsigned int cpu;
 175        int rc;
 176
 177        /*
 178         * Always reserve area for module percpu variables.  That's
 179         * what the legacy allocator did.
 180         */
 181        rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE,
 182                                    PERCPU_DYNAMIC_RESERVE, PAGE_SIZE,
 183                                    pcpu_cpu_distance,
 184                                    pcpu_fc_alloc, pcpu_fc_free);
 185        if (rc < 0)
 186                panic("Failed to initialize percpu areas.");
 187
 188        delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
 189        for_each_possible_cpu(cpu)
 190                __per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];
 191}
 192#endif
 193
 194/**
 195 * numa_add_memblk() - Set node id to memblk
 196 * @nid: NUMA node ID of the new memblk
 197 * @start: Start address of the new memblk
 198 * @end:  End address of the new memblk
 199 *
 200 * RETURNS:
 201 * 0 on success, -errno on failure.
 202 */
 203int __init numa_add_memblk(int nid, u64 start, u64 end)
 204{
 205        int ret;
 206
 207        ret = memblock_set_node(start, (end - start), &memblock.memory, nid);
 208        if (ret < 0) {
 209                pr_err("memblock [0x%llx - 0x%llx] failed to add on node %d\n",
 210                        start, (end - 1), nid);
 211                return ret;
 212        }
 213
 214        node_set(nid, numa_nodes_parsed);
 215        return ret;
 216}
 217
 218/*
 219 * Initialize NODE_DATA for a node on the local memory
 220 */
 221static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn)
 222{
 223        const size_t nd_size = roundup(sizeof(pg_data_t), SMP_CACHE_BYTES);
 224        u64 nd_pa;
 225        void *nd;
 226        int tnid;
 227
 228        if (start_pfn >= end_pfn)
 229                pr_info("Initmem setup node %d [<memory-less node>]\n", nid);
 230
 231        nd_pa = memblock_phys_alloc_try_nid(nd_size, SMP_CACHE_BYTES, nid);
 232        if (!nd_pa)
 233                panic("Cannot allocate %zu bytes for node %d data\n",
 234                      nd_size, nid);
 235
 236        nd = __va(nd_pa);
 237
 238        /* report and initialize */
 239        pr_info("NODE_DATA [mem %#010Lx-%#010Lx]\n",
 240                nd_pa, nd_pa + nd_size - 1);
 241        tnid = early_pfn_to_nid(nd_pa >> PAGE_SHIFT);
 242        if (tnid != nid)
 243                pr_info("NODE_DATA(%d) on node %d\n", nid, tnid);
 244
 245        node_data[nid] = nd;
 246        memset(NODE_DATA(nid), 0, sizeof(pg_data_t));
 247        NODE_DATA(nid)->node_id = nid;
 248        NODE_DATA(nid)->node_start_pfn = start_pfn;
 249        NODE_DATA(nid)->node_spanned_pages = end_pfn - start_pfn;
 250}
 251
 252/*
 253 * numa_free_distance
 254 *
 255 * The current table is freed.
 256 */
 257void __init numa_free_distance(void)
 258{
 259        size_t size;
 260
 261        if (!numa_distance)
 262                return;
 263
 264        size = numa_distance_cnt * numa_distance_cnt *
 265                sizeof(numa_distance[0]);
 266
 267        memblock_free(__pa(numa_distance), size);
 268        numa_distance_cnt = 0;
 269        numa_distance = NULL;
 270}
 271
 272/*
 273 * Create a new NUMA distance table.
 274 */
 275static int __init numa_alloc_distance(void)
 276{
 277        size_t size;
 278        u64 phys;
 279        int i, j;
 280
 281        size = nr_node_ids * nr_node_ids * sizeof(numa_distance[0]);
 282        phys = memblock_find_in_range(0, PFN_PHYS(max_pfn),
 283                                      size, PAGE_SIZE);
 284        if (WARN_ON(!phys))
 285                return -ENOMEM;
 286
 287        memblock_reserve(phys, size);
 288
 289        numa_distance = __va(phys);
 290        numa_distance_cnt = nr_node_ids;
 291
 292        /* fill with the default distances */
 293        for (i = 0; i < numa_distance_cnt; i++)
 294                for (j = 0; j < numa_distance_cnt; j++)
 295                        numa_distance[i * numa_distance_cnt + j] = i == j ?
 296                                LOCAL_DISTANCE : REMOTE_DISTANCE;
 297
 298        pr_debug("Initialized distance table, cnt=%d\n", numa_distance_cnt);
 299
 300        return 0;
 301}
 302
 303/**
 304 * numa_set_distance() - Set inter node NUMA distance from node to node.
 305 * @from: the 'from' node to set distance
 306 * @to: the 'to'  node to set distance
 307 * @distance: NUMA distance
 308 *
 309 * Set the distance from node @from to @to to @distance.
 310 * If distance table doesn't exist, a warning is printed.
 311 *
 312 * If @from or @to is higher than the highest known node or lower than zero
 313 * or @distance doesn't make sense, the call is ignored.
 314 */
 315void __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 */
 342int __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}
 348EXPORT_SYMBOL(__node_distance);
 349
 350static 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_mem_region(mblk) {
 357                int mblk_nid = memblock_get_region_node(mblk);
 358                phys_addr_t start = mblk->base;
 359                phys_addr_t end = mblk->base + mblk->size - 1;
 360
 361                if (mblk_nid == NUMA_NO_NODE || mblk_nid >= MAX_NUMNODES) {
 362                        pr_warn("Warning: invalid memblk node %d [mem %pap-%pap]\n",
 363                                mblk_nid, &start, &end);
 364                        return -EINVAL;
 365                }
 366        }
 367
 368        /* Finally register nodes. */
 369        for_each_node_mask(nid, numa_nodes_parsed) {
 370                unsigned long start_pfn, end_pfn;
 371
 372                get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
 373                setup_node_data(nid, start_pfn, end_pfn);
 374                node_set_online(nid);
 375        }
 376
 377        /* Setup online nodes to actual nodes*/
 378        node_possible_map = numa_nodes_parsed;
 379
 380        return 0;
 381}
 382
 383static int __init numa_init(int (*init_func)(void))
 384{
 385        int ret;
 386
 387        nodes_clear(numa_nodes_parsed);
 388        nodes_clear(node_possible_map);
 389        nodes_clear(node_online_map);
 390
 391        ret = numa_alloc_distance();
 392        if (ret < 0)
 393                return ret;
 394
 395        ret = init_func();
 396        if (ret < 0)
 397                goto out_free_distance;
 398
 399        if (nodes_empty(numa_nodes_parsed)) {
 400                pr_info("No NUMA configuration found\n");
 401                ret = -EINVAL;
 402                goto out_free_distance;
 403        }
 404
 405        ret = numa_register_nodes();
 406        if (ret < 0)
 407                goto out_free_distance;
 408
 409        setup_node_to_cpumask_map();
 410
 411        return 0;
 412out_free_distance:
 413        numa_free_distance();
 414        return ret;
 415}
 416
 417/**
 418 * dummy_numa_init() - Fallback dummy NUMA init
 419 *
 420 * Used if there's no underlying NUMA architecture, NUMA initialization
 421 * fails, or NUMA is disabled on the command line.
 422 *
 423 * Must online at least one node (node 0) and add memory blocks that cover all
 424 * allowed memory. It is unlikely that this function fails.
 425 *
 426 * Return: 0 on success, -errno on failure.
 427 */
 428static int __init dummy_numa_init(void)
 429{
 430        phys_addr_t start = memblock_start_of_DRAM();
 431        phys_addr_t end = memblock_end_of_DRAM() - 1;
 432        int ret;
 433
 434        if (numa_off)
 435                pr_info("NUMA disabled\n"); /* Forced off on command line. */
 436        pr_info("Faking a node at [mem %pap-%pap]\n", &start, &end);
 437
 438        ret = numa_add_memblk(0, start, end + 1);
 439        if (ret) {
 440                pr_err("NUMA init failed\n");
 441                return ret;
 442        }
 443
 444        numa_off = true;
 445        return 0;
 446}
 447
 448#ifdef CONFIG_ACPI_NUMA
 449static int __init arch_acpi_numa_init(void)
 450{
 451        int ret;
 452
 453        ret = acpi_numa_init();
 454        if (ret) {
 455                pr_info("Failed to initialise from firmware\n");
 456                return ret;
 457        }
 458
 459        return srat_disabled() ? -EINVAL : 0;
 460}
 461#else
 462static int __init arch_acpi_numa_init(void)
 463{
 464        return -EOPNOTSUPP;
 465}
 466#endif
 467
 468/**
 469 * arch_numa_init() - Initialize NUMA
 470 *
 471 * Try each configured NUMA initialization method until one succeeds. The
 472 * last fallback is dummy single node config encompassing whole memory.
 473 */
 474void __init arch_numa_init(void)
 475{
 476        if (!numa_off) {
 477                if (!acpi_disabled && !numa_init(arch_acpi_numa_init))
 478                        return;
 479                if (acpi_disabled && !numa_init(of_numa_init))
 480                        return;
 481        }
 482
 483        numa_init(dummy_numa_init);
 484}
 485