numa_64.c 16 KB

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  1. /*
  2. * Generic VM initialization for x86-64 NUMA setups.
  3. * Copyright 2002,2003 Andi Kleen, SuSE Labs.
  4. */
  5. #include <linux/kernel.h>
  6. #include <linux/mm.h>
  7. #include <linux/string.h>
  8. #include <linux/init.h>
  9. #include <linux/bootmem.h>
  10. #include <linux/mmzone.h>
  11. #include <linux/ctype.h>
  12. #include <linux/module.h>
  13. #include <linux/nodemask.h>
  14. #include <linux/sched.h>
  15. #include <asm/e820.h>
  16. #include <asm/proto.h>
  17. #include <asm/dma.h>
  18. #include <asm/numa.h>
  19. #include <asm/acpi.h>
  20. #include <asm/k8.h>
  21. #ifndef Dprintk
  22. #define Dprintk(x...)
  23. #endif
  24. struct pglist_data *node_data[MAX_NUMNODES] __read_mostly;
  25. EXPORT_SYMBOL(node_data);
  26. bootmem_data_t plat_node_bdata[MAX_NUMNODES];
  27. struct memnode memnode;
  28. int x86_cpu_to_node_map_init[NR_CPUS] = {
  29. [0 ... NR_CPUS-1] = NUMA_NO_NODE
  30. };
  31. void *x86_cpu_to_node_map_early_ptr;
  32. DEFINE_PER_CPU(int, x86_cpu_to_node_map) = NUMA_NO_NODE;
  33. EXPORT_PER_CPU_SYMBOL(x86_cpu_to_node_map);
  34. EXPORT_SYMBOL(x86_cpu_to_node_map_early_ptr);
  35. s16 apicid_to_node[MAX_LOCAL_APIC] __cpuinitdata = {
  36. [0 ... MAX_LOCAL_APIC-1] = NUMA_NO_NODE
  37. };
  38. cpumask_t node_to_cpumask_map[MAX_NUMNODES] __read_mostly;
  39. EXPORT_SYMBOL(node_to_cpumask_map);
  40. int numa_off __initdata;
  41. unsigned long __initdata nodemap_addr;
  42. unsigned long __initdata nodemap_size;
  43. /*
  44. * Given a shift value, try to populate memnodemap[]
  45. * Returns :
  46. * 1 if OK
  47. * 0 if memnodmap[] too small (of shift too small)
  48. * -1 if node overlap or lost ram (shift too big)
  49. */
  50. static int __init populate_memnodemap(const struct bootnode *nodes,
  51. int numnodes, int shift)
  52. {
  53. unsigned long addr, end;
  54. int i, res = -1;
  55. memset(memnodemap, 0xff, sizeof(s16)*memnodemapsize);
  56. for (i = 0; i < numnodes; i++) {
  57. addr = nodes[i].start;
  58. end = nodes[i].end;
  59. if (addr >= end)
  60. continue;
  61. if ((end >> shift) >= memnodemapsize)
  62. return 0;
  63. do {
  64. if (memnodemap[addr >> shift] != NUMA_NO_NODE)
  65. return -1;
  66. memnodemap[addr >> shift] = i;
  67. addr += (1UL << shift);
  68. } while (addr < end);
  69. res = 1;
  70. }
  71. return res;
  72. }
  73. static int __init allocate_cachealigned_memnodemap(void)
  74. {
  75. unsigned long addr;
  76. memnodemap = memnode.embedded_map;
  77. if (memnodemapsize <= ARRAY_SIZE(memnode.embedded_map))
  78. return 0;
  79. addr = 0x8000;
  80. nodemap_size = round_up(sizeof(s16) * memnodemapsize, L1_CACHE_BYTES);
  81. nodemap_addr = find_e820_area(addr, end_pfn<<PAGE_SHIFT,
  82. nodemap_size, L1_CACHE_BYTES);
  83. if (nodemap_addr == -1UL) {
  84. printk(KERN_ERR
  85. "NUMA: Unable to allocate Memory to Node hash map\n");
  86. nodemap_addr = nodemap_size = 0;
  87. return -1;
  88. }
  89. memnodemap = phys_to_virt(nodemap_addr);
  90. reserve_early(nodemap_addr, nodemap_addr + nodemap_size, "MEMNODEMAP");
  91. printk(KERN_DEBUG "NUMA: Allocated memnodemap from %lx - %lx\n",
  92. nodemap_addr, nodemap_addr + nodemap_size);
  93. return 0;
  94. }
  95. /*
  96. * The LSB of all start and end addresses in the node map is the value of the
  97. * maximum possible shift.
  98. */
  99. static int __init extract_lsb_from_nodes(const struct bootnode *nodes,
  100. int numnodes)
  101. {
  102. int i, nodes_used = 0;
  103. unsigned long start, end;
  104. unsigned long bitfield = 0, memtop = 0;
  105. for (i = 0; i < numnodes; i++) {
  106. start = nodes[i].start;
  107. end = nodes[i].end;
  108. if (start >= end)
  109. continue;
  110. bitfield |= start;
  111. nodes_used++;
  112. if (end > memtop)
  113. memtop = end;
  114. }
  115. if (nodes_used <= 1)
  116. i = 63;
  117. else
  118. i = find_first_bit(&bitfield, sizeof(unsigned long)*8);
  119. memnodemapsize = (memtop >> i)+1;
  120. return i;
  121. }
  122. int __init compute_hash_shift(struct bootnode *nodes, int numnodes)
  123. {
  124. int shift;
  125. shift = extract_lsb_from_nodes(nodes, numnodes);
  126. if (allocate_cachealigned_memnodemap())
  127. return -1;
  128. printk(KERN_DEBUG "NUMA: Using %d for the hash shift.\n",
  129. shift);
  130. if (populate_memnodemap(nodes, numnodes, shift) != 1) {
  131. printk(KERN_INFO "Your memory is not aligned you need to "
  132. "rebuild your kernel with a bigger NODEMAPSIZE "
  133. "shift=%d\n", shift);
  134. return -1;
  135. }
  136. return shift;
  137. }
  138. int early_pfn_to_nid(unsigned long pfn)
  139. {
  140. return phys_to_nid(pfn << PAGE_SHIFT);
  141. }
  142. static void * __init early_node_mem(int nodeid, unsigned long start,
  143. unsigned long end, unsigned long size,
  144. unsigned long align)
  145. {
  146. unsigned long mem = find_e820_area(start, end, size, align);
  147. void *ptr;
  148. if (mem != -1L)
  149. return __va(mem);
  150. ptr = __alloc_bootmem_nopanic(size, align, __pa(MAX_DMA_ADDRESS));
  151. if (ptr == NULL) {
  152. printk(KERN_ERR "Cannot find %lu bytes in node %d\n",
  153. size, nodeid);
  154. return NULL;
  155. }
  156. return ptr;
  157. }
  158. /* Initialize bootmem allocator for a node */
  159. void __init setup_node_bootmem(int nodeid, unsigned long start,
  160. unsigned long end)
  161. {
  162. unsigned long start_pfn, end_pfn, bootmap_pages, bootmap_size;
  163. unsigned long bootmap_start, nodedata_phys;
  164. void *bootmap;
  165. const int pgdat_size = round_up(sizeof(pg_data_t), PAGE_SIZE);
  166. start = round_up(start, ZONE_ALIGN);
  167. printk(KERN_INFO "Bootmem setup node %d %016lx-%016lx\n", nodeid,
  168. start, end);
  169. start_pfn = start >> PAGE_SHIFT;
  170. end_pfn = end >> PAGE_SHIFT;
  171. node_data[nodeid] = early_node_mem(nodeid, start, end, pgdat_size,
  172. SMP_CACHE_BYTES);
  173. if (node_data[nodeid] == NULL)
  174. return;
  175. nodedata_phys = __pa(node_data[nodeid]);
  176. memset(NODE_DATA(nodeid), 0, sizeof(pg_data_t));
  177. NODE_DATA(nodeid)->bdata = &plat_node_bdata[nodeid];
  178. NODE_DATA(nodeid)->node_start_pfn = start_pfn;
  179. NODE_DATA(nodeid)->node_spanned_pages = end_pfn - start_pfn;
  180. /* Find a place for the bootmem map */
  181. bootmap_pages = bootmem_bootmap_pages(end_pfn - start_pfn);
  182. bootmap_start = round_up(nodedata_phys + pgdat_size, PAGE_SIZE);
  183. /*
  184. * SMP_CAHCE_BYTES could be enough, but init_bootmem_node like
  185. * to use that to align to PAGE_SIZE
  186. */
  187. bootmap = early_node_mem(nodeid, bootmap_start, end,
  188. bootmap_pages<<PAGE_SHIFT, PAGE_SIZE);
  189. if (bootmap == NULL) {
  190. if (nodedata_phys < start || nodedata_phys >= end)
  191. free_bootmem((unsigned long)node_data[nodeid],
  192. pgdat_size);
  193. node_data[nodeid] = NULL;
  194. return;
  195. }
  196. bootmap_start = __pa(bootmap);
  197. Dprintk("bootmap start %lu pages %lu\n", bootmap_start, bootmap_pages);
  198. bootmap_size = init_bootmem_node(NODE_DATA(nodeid),
  199. bootmap_start >> PAGE_SHIFT,
  200. start_pfn, end_pfn);
  201. free_bootmem_with_active_regions(nodeid, end);
  202. reserve_bootmem_node(NODE_DATA(nodeid), nodedata_phys, pgdat_size);
  203. reserve_bootmem_node(NODE_DATA(nodeid), bootmap_start,
  204. bootmap_pages<<PAGE_SHIFT);
  205. #ifdef CONFIG_ACPI_NUMA
  206. srat_reserve_add_area(nodeid);
  207. #endif
  208. node_set_online(nodeid);
  209. }
  210. /*
  211. * There are unfortunately some poorly designed mainboards around that
  212. * only connect memory to a single CPU. This breaks the 1:1 cpu->node
  213. * mapping. To avoid this fill in the mapping for all possible CPUs,
  214. * as the number of CPUs is not known yet. We round robin the existing
  215. * nodes.
  216. */
  217. void __init numa_init_array(void)
  218. {
  219. int rr, i;
  220. rr = first_node(node_online_map);
  221. for (i = 0; i < NR_CPUS; i++) {
  222. if (early_cpu_to_node(i) != NUMA_NO_NODE)
  223. continue;
  224. numa_set_node(i, rr);
  225. rr = next_node(rr, node_online_map);
  226. if (rr == MAX_NUMNODES)
  227. rr = first_node(node_online_map);
  228. }
  229. }
  230. #ifdef CONFIG_NUMA_EMU
  231. /* Numa emulation */
  232. char *cmdline __initdata;
  233. /*
  234. * Setups up nid to range from addr to addr + size. If the end
  235. * boundary is greater than max_addr, then max_addr is used instead.
  236. * The return value is 0 if there is additional memory left for
  237. * allocation past addr and -1 otherwise. addr is adjusted to be at
  238. * the end of the node.
  239. */
  240. static int __init setup_node_range(int nid, struct bootnode *nodes, u64 *addr,
  241. u64 size, u64 max_addr)
  242. {
  243. int ret = 0;
  244. nodes[nid].start = *addr;
  245. *addr += size;
  246. if (*addr >= max_addr) {
  247. *addr = max_addr;
  248. ret = -1;
  249. }
  250. nodes[nid].end = *addr;
  251. node_set(nid, node_possible_map);
  252. printk(KERN_INFO "Faking node %d at %016Lx-%016Lx (%LuMB)\n", nid,
  253. nodes[nid].start, nodes[nid].end,
  254. (nodes[nid].end - nodes[nid].start) >> 20);
  255. return ret;
  256. }
  257. /*
  258. * Splits num_nodes nodes up equally starting at node_start. The return value
  259. * is the number of nodes split up and addr is adjusted to be at the end of the
  260. * last node allocated.
  261. */
  262. static int __init split_nodes_equally(struct bootnode *nodes, u64 *addr,
  263. u64 max_addr, int node_start,
  264. int num_nodes)
  265. {
  266. unsigned int big;
  267. u64 size;
  268. int i;
  269. if (num_nodes <= 0)
  270. return -1;
  271. if (num_nodes > MAX_NUMNODES)
  272. num_nodes = MAX_NUMNODES;
  273. size = (max_addr - *addr - e820_hole_size(*addr, max_addr)) /
  274. num_nodes;
  275. /*
  276. * Calculate the number of big nodes that can be allocated as a result
  277. * of consolidating the leftovers.
  278. */
  279. big = ((size & ~FAKE_NODE_MIN_HASH_MASK) * num_nodes) /
  280. FAKE_NODE_MIN_SIZE;
  281. /* Round down to nearest FAKE_NODE_MIN_SIZE. */
  282. size &= FAKE_NODE_MIN_HASH_MASK;
  283. if (!size) {
  284. printk(KERN_ERR "Not enough memory for each node. "
  285. "NUMA emulation disabled.\n");
  286. return -1;
  287. }
  288. for (i = node_start; i < num_nodes + node_start; i++) {
  289. u64 end = *addr + size;
  290. if (i < big)
  291. end += FAKE_NODE_MIN_SIZE;
  292. /*
  293. * The final node can have the remaining system RAM. Other
  294. * nodes receive roughly the same amount of available pages.
  295. */
  296. if (i == num_nodes + node_start - 1)
  297. end = max_addr;
  298. else
  299. while (end - *addr - e820_hole_size(*addr, end) <
  300. size) {
  301. end += FAKE_NODE_MIN_SIZE;
  302. if (end > max_addr) {
  303. end = max_addr;
  304. break;
  305. }
  306. }
  307. if (setup_node_range(i, nodes, addr, end - *addr, max_addr) < 0)
  308. break;
  309. }
  310. return i - node_start + 1;
  311. }
  312. /*
  313. * Splits the remaining system RAM into chunks of size. The remaining memory is
  314. * always assigned to a final node and can be asymmetric. Returns the number of
  315. * nodes split.
  316. */
  317. static int __init split_nodes_by_size(struct bootnode *nodes, u64 *addr,
  318. u64 max_addr, int node_start, u64 size)
  319. {
  320. int i = node_start;
  321. size = (size << 20) & FAKE_NODE_MIN_HASH_MASK;
  322. while (!setup_node_range(i++, nodes, addr, size, max_addr))
  323. ;
  324. return i - node_start;
  325. }
  326. /*
  327. * Sets up the system RAM area from start_pfn to end_pfn according to the
  328. * numa=fake command-line option.
  329. */
  330. static int __init numa_emulation(unsigned long start_pfn, unsigned long end_pfn)
  331. {
  332. struct bootnode nodes[MAX_NUMNODES];
  333. u64 size, addr = start_pfn << PAGE_SHIFT;
  334. u64 max_addr = end_pfn << PAGE_SHIFT;
  335. int num_nodes = 0, num = 0, coeff_flag, coeff = -1, i;
  336. memset(&nodes, 0, sizeof(nodes));
  337. /*
  338. * If the numa=fake command-line is just a single number N, split the
  339. * system RAM into N fake nodes.
  340. */
  341. if (!strchr(cmdline, '*') && !strchr(cmdline, ',')) {
  342. long n = simple_strtol(cmdline, NULL, 0);
  343. num_nodes = split_nodes_equally(nodes, &addr, max_addr, 0, n);
  344. if (num_nodes < 0)
  345. return num_nodes;
  346. goto out;
  347. }
  348. /* Parse the command line. */
  349. for (coeff_flag = 0; ; cmdline++) {
  350. if (*cmdline && isdigit(*cmdline)) {
  351. num = num * 10 + *cmdline - '0';
  352. continue;
  353. }
  354. if (*cmdline == '*') {
  355. if (num > 0)
  356. coeff = num;
  357. coeff_flag = 1;
  358. }
  359. if (!*cmdline || *cmdline == ',') {
  360. if (!coeff_flag)
  361. coeff = 1;
  362. /*
  363. * Round down to the nearest FAKE_NODE_MIN_SIZE.
  364. * Command-line coefficients are in megabytes.
  365. */
  366. size = ((u64)num << 20) & FAKE_NODE_MIN_HASH_MASK;
  367. if (size)
  368. for (i = 0; i < coeff; i++, num_nodes++)
  369. if (setup_node_range(num_nodes, nodes,
  370. &addr, size, max_addr) < 0)
  371. goto done;
  372. if (!*cmdline)
  373. break;
  374. coeff_flag = 0;
  375. coeff = -1;
  376. }
  377. num = 0;
  378. }
  379. done:
  380. if (!num_nodes)
  381. return -1;
  382. /* Fill remainder of system RAM, if appropriate. */
  383. if (addr < max_addr) {
  384. if (coeff_flag && coeff < 0) {
  385. /* Split remaining nodes into num-sized chunks */
  386. num_nodes += split_nodes_by_size(nodes, &addr, max_addr,
  387. num_nodes, num);
  388. goto out;
  389. }
  390. switch (*(cmdline - 1)) {
  391. case '*':
  392. /* Split remaining nodes into coeff chunks */
  393. if (coeff <= 0)
  394. break;
  395. num_nodes += split_nodes_equally(nodes, &addr, max_addr,
  396. num_nodes, coeff);
  397. break;
  398. case ',':
  399. /* Do not allocate remaining system RAM */
  400. break;
  401. default:
  402. /* Give one final node */
  403. setup_node_range(num_nodes, nodes, &addr,
  404. max_addr - addr, max_addr);
  405. num_nodes++;
  406. }
  407. }
  408. out:
  409. memnode_shift = compute_hash_shift(nodes, num_nodes);
  410. if (memnode_shift < 0) {
  411. memnode_shift = 0;
  412. printk(KERN_ERR "No NUMA hash function found. NUMA emulation "
  413. "disabled.\n");
  414. return -1;
  415. }
  416. /*
  417. * We need to vacate all active ranges that may have been registered by
  418. * SRAT and set acpi_numa to -1 so that srat_disabled() always returns
  419. * true. NUMA emulation has succeeded so we will not scan ACPI nodes.
  420. */
  421. remove_all_active_ranges();
  422. #ifdef CONFIG_ACPI_NUMA
  423. acpi_numa = -1;
  424. #endif
  425. for_each_node_mask(i, node_possible_map) {
  426. e820_register_active_regions(i, nodes[i].start >> PAGE_SHIFT,
  427. nodes[i].end >> PAGE_SHIFT);
  428. setup_node_bootmem(i, nodes[i].start, nodes[i].end);
  429. }
  430. acpi_fake_nodes(nodes, num_nodes);
  431. numa_init_array();
  432. return 0;
  433. }
  434. #endif /* CONFIG_NUMA_EMU */
  435. void __init numa_initmem_init(unsigned long start_pfn, unsigned long end_pfn)
  436. {
  437. int i;
  438. nodes_clear(node_possible_map);
  439. #ifdef CONFIG_NUMA_EMU
  440. if (cmdline && !numa_emulation(start_pfn, end_pfn))
  441. return;
  442. nodes_clear(node_possible_map);
  443. #endif
  444. #ifdef CONFIG_ACPI_NUMA
  445. if (!numa_off && !acpi_scan_nodes(start_pfn << PAGE_SHIFT,
  446. end_pfn << PAGE_SHIFT))
  447. return;
  448. nodes_clear(node_possible_map);
  449. #endif
  450. #ifdef CONFIG_K8_NUMA
  451. if (!numa_off && !k8_scan_nodes(start_pfn<<PAGE_SHIFT,
  452. end_pfn<<PAGE_SHIFT))
  453. return;
  454. nodes_clear(node_possible_map);
  455. #endif
  456. printk(KERN_INFO "%s\n",
  457. numa_off ? "NUMA turned off" : "No NUMA configuration found");
  458. printk(KERN_INFO "Faking a node at %016lx-%016lx\n",
  459. start_pfn << PAGE_SHIFT,
  460. end_pfn << PAGE_SHIFT);
  461. /* setup dummy node covering all memory */
  462. memnode_shift = 63;
  463. memnodemap = memnode.embedded_map;
  464. memnodemap[0] = 0;
  465. nodes_clear(node_online_map);
  466. node_set_online(0);
  467. node_set(0, node_possible_map);
  468. for (i = 0; i < NR_CPUS; i++)
  469. numa_set_node(i, 0);
  470. /* cpumask_of_cpu() may not be available during early startup */
  471. memset(&node_to_cpumask_map[0], 0, sizeof(node_to_cpumask_map[0]));
  472. cpu_set(0, node_to_cpumask_map[0]);
  473. e820_register_active_regions(0, start_pfn, end_pfn);
  474. setup_node_bootmem(0, start_pfn << PAGE_SHIFT, end_pfn << PAGE_SHIFT);
  475. }
  476. __cpuinit void numa_add_cpu(int cpu)
  477. {
  478. set_bit(cpu,
  479. (unsigned long *)&node_to_cpumask_map[early_cpu_to_node(cpu)]);
  480. }
  481. void __cpuinit numa_set_node(int cpu, int node)
  482. {
  483. int *cpu_to_node_map = x86_cpu_to_node_map_early_ptr;
  484. cpu_pda(cpu)->nodenumber = node;
  485. if(cpu_to_node_map)
  486. cpu_to_node_map[cpu] = node;
  487. else if(per_cpu_offset(cpu))
  488. per_cpu(x86_cpu_to_node_map, cpu) = node;
  489. else
  490. Dprintk(KERN_INFO "Setting node for non-present cpu %d\n", cpu);
  491. }
  492. unsigned long __init numa_free_all_bootmem(void)
  493. {
  494. unsigned long pages = 0;
  495. int i;
  496. for_each_online_node(i)
  497. pages += free_all_bootmem_node(NODE_DATA(i));
  498. return pages;
  499. }
  500. void __init paging_init(void)
  501. {
  502. unsigned long max_zone_pfns[MAX_NR_ZONES];
  503. memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
  504. max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
  505. max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
  506. max_zone_pfns[ZONE_NORMAL] = end_pfn;
  507. sparse_memory_present_with_active_regions(MAX_NUMNODES);
  508. sparse_init();
  509. free_area_init_nodes(max_zone_pfns);
  510. }
  511. static __init int numa_setup(char *opt)
  512. {
  513. if (!opt)
  514. return -EINVAL;
  515. if (!strncmp(opt, "off", 3))
  516. numa_off = 1;
  517. #ifdef CONFIG_NUMA_EMU
  518. if (!strncmp(opt, "fake=", 5))
  519. cmdline = opt + 5;
  520. #endif
  521. #ifdef CONFIG_ACPI_NUMA
  522. if (!strncmp(opt, "noacpi", 6))
  523. acpi_numa = -1;
  524. if (!strncmp(opt, "hotadd=", 7))
  525. hotadd_percent = simple_strtoul(opt+7, NULL, 10);
  526. #endif
  527. return 0;
  528. }
  529. early_param("numa", numa_setup);
  530. /*
  531. * Setup early cpu_to_node.
  532. *
  533. * Populate cpu_to_node[] only if x86_cpu_to_apicid[],
  534. * and apicid_to_node[] tables have valid entries for a CPU.
  535. * This means we skip cpu_to_node[] initialisation for NUMA
  536. * emulation and faking node case (when running a kernel compiled
  537. * for NUMA on a non NUMA box), which is OK as cpu_to_node[]
  538. * is already initialized in a round robin manner at numa_init_array,
  539. * prior to this call, and this initialization is good enough
  540. * for the fake NUMA cases.
  541. */
  542. void __init init_cpu_to_node(void)
  543. {
  544. int i;
  545. for (i = 0; i < NR_CPUS; i++) {
  546. u16 apicid = x86_cpu_to_apicid_init[i];
  547. if (apicid == BAD_APICID)
  548. continue;
  549. if (apicid_to_node[apicid] == NUMA_NO_NODE)
  550. continue;
  551. numa_set_node(i, apicid_to_node[apicid]);
  552. }
  553. }