numa_64.c 17 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. u16 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(u16, x86_cpu_to_node_map) = NUMA_NO_NODE;
  33. EXPORT_PER_CPU_SYMBOL(x86_cpu_to_node_map);
  34. u16 apicid_to_node[MAX_LOCAL_APIC] __cpuinitdata = {
  35. [0 ... MAX_LOCAL_APIC-1] = NUMA_NO_NODE
  36. };
  37. cpumask_t node_to_cpumask_map[MAX_NUMNODES] __read_mostly;
  38. EXPORT_SYMBOL(node_to_cpumask_map);
  39. int numa_off __initdata;
  40. unsigned long __initdata nodemap_addr;
  41. unsigned long __initdata nodemap_size;
  42. /*
  43. * Given a shift value, try to populate memnodemap[]
  44. * Returns :
  45. * 1 if OK
  46. * 0 if memnodmap[] too small (of shift too small)
  47. * -1 if node overlap or lost ram (shift too big)
  48. */
  49. static int __init populate_memnodemap(const struct bootnode *nodes,
  50. int numnodes, int shift)
  51. {
  52. unsigned long addr, end;
  53. int i, res = -1;
  54. memset(memnodemap, 0xff, memnodemapsize);
  55. for (i = 0; i < numnodes; i++) {
  56. addr = nodes[i].start;
  57. end = nodes[i].end;
  58. if (addr >= end)
  59. continue;
  60. if ((end >> shift) >= memnodemapsize)
  61. return 0;
  62. do {
  63. if (memnodemap[addr >> shift] != 0xff)
  64. return -1;
  65. memnodemap[addr >> shift] = i;
  66. addr += (1UL << shift);
  67. } while (addr < end);
  68. res = 1;
  69. }
  70. return res;
  71. }
  72. static int __init allocate_cachealigned_memnodemap(void)
  73. {
  74. unsigned long pad, pad_addr;
  75. memnodemap = memnode.embedded_map;
  76. if (memnodemapsize <= ARRAY_SIZE(memnode.embedded_map))
  77. return 0;
  78. pad = L1_CACHE_BYTES - 1;
  79. pad_addr = 0x8000;
  80. nodemap_size = pad + memnodemapsize;
  81. nodemap_addr = find_e820_area(pad_addr, end_pfn<<PAGE_SHIFT,
  82. nodemap_size);
  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. pad_addr = (nodemap_addr + pad) & ~pad;
  90. memnodemap = phys_to_virt(pad_addr);
  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. {
  145. unsigned long mem = find_e820_area(start, end, size);
  146. void *ptr;
  147. if (mem != -1L)
  148. return __va(mem);
  149. ptr = __alloc_bootmem_nopanic(size,
  150. SMP_CACHE_BYTES, __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. if (node_data[nodeid] == NULL)
  173. return;
  174. nodedata_phys = __pa(node_data[nodeid]);
  175. memset(NODE_DATA(nodeid), 0, sizeof(pg_data_t));
  176. NODE_DATA(nodeid)->bdata = &plat_node_bdata[nodeid];
  177. NODE_DATA(nodeid)->node_start_pfn = start_pfn;
  178. NODE_DATA(nodeid)->node_spanned_pages = end_pfn - start_pfn;
  179. /* Find a place for the bootmem map */
  180. bootmap_pages = bootmem_bootmap_pages(end_pfn - start_pfn);
  181. bootmap_start = round_up(nodedata_phys + pgdat_size, PAGE_SIZE);
  182. bootmap = early_node_mem(nodeid, bootmap_start, end,
  183. bootmap_pages<<PAGE_SHIFT);
  184. if (bootmap == NULL) {
  185. if (nodedata_phys < start || nodedata_phys >= end)
  186. free_bootmem((unsigned long)node_data[nodeid],
  187. pgdat_size);
  188. node_data[nodeid] = NULL;
  189. return;
  190. }
  191. bootmap_start = __pa(bootmap);
  192. Dprintk("bootmap start %lu pages %lu\n", bootmap_start, bootmap_pages);
  193. bootmap_size = init_bootmem_node(NODE_DATA(nodeid),
  194. bootmap_start >> PAGE_SHIFT,
  195. start_pfn, end_pfn);
  196. free_bootmem_with_active_regions(nodeid, end);
  197. reserve_bootmem_node(NODE_DATA(nodeid), nodedata_phys, pgdat_size);
  198. reserve_bootmem_node(NODE_DATA(nodeid), bootmap_start,
  199. bootmap_pages<<PAGE_SHIFT);
  200. #ifdef CONFIG_ACPI_NUMA
  201. srat_reserve_add_area(nodeid);
  202. #endif
  203. node_set_online(nodeid);
  204. }
  205. #ifdef CONFIG_FLAT_NODE_MEM_MAP
  206. /* Initialize final allocator for a zone */
  207. static void __init flat_setup_node_zones(int nodeid)
  208. {
  209. unsigned long start_pfn, end_pfn, memmapsize, limit;
  210. start_pfn = node_start_pfn(nodeid);
  211. end_pfn = node_end_pfn(nodeid);
  212. Dprintk(KERN_INFO "Setting up memmap for node %d %lx-%lx\n",
  213. nodeid, start_pfn, end_pfn);
  214. /*
  215. * Try to allocate mem_map at end to not fill up precious <4GB
  216. * memory.
  217. */
  218. memmapsize = sizeof(struct page) * (end_pfn-start_pfn);
  219. limit = end_pfn << PAGE_SHIFT;
  220. NODE_DATA(nodeid)->node_mem_map =
  221. __alloc_bootmem_core(NODE_DATA(nodeid)->bdata,
  222. memmapsize, SMP_CACHE_BYTES,
  223. round_down(limit - memmapsize, PAGE_SIZE),
  224. limit);
  225. }
  226. #else
  227. #define flat_setup_node_zones(i) do {} while (0)
  228. #endif
  229. /*
  230. * There are unfortunately some poorly designed mainboards around that
  231. * only connect memory to a single CPU. This breaks the 1:1 cpu->node
  232. * mapping. To avoid this fill in the mapping for all possible CPUs,
  233. * as the number of CPUs is not known yet. We round robin the existing
  234. * nodes.
  235. */
  236. void __init numa_init_array(void)
  237. {
  238. int rr, i;
  239. rr = first_node(node_online_map);
  240. for (i = 0; i < NR_CPUS; i++) {
  241. if (cpu_to_node(i) != NUMA_NO_NODE)
  242. continue;
  243. numa_set_node(i, rr);
  244. rr = next_node(rr, node_online_map);
  245. if (rr == MAX_NUMNODES)
  246. rr = first_node(node_online_map);
  247. }
  248. }
  249. #ifdef CONFIG_NUMA_EMU
  250. /* Numa emulation */
  251. char *cmdline __initdata;
  252. /*
  253. * Setups up nid to range from addr to addr + size. If the end
  254. * boundary is greater than max_addr, then max_addr is used instead.
  255. * The return value is 0 if there is additional memory left for
  256. * allocation past addr and -1 otherwise. addr is adjusted to be at
  257. * the end of the node.
  258. */
  259. static int __init setup_node_range(int nid, struct bootnode *nodes, u64 *addr,
  260. u64 size, u64 max_addr)
  261. {
  262. int ret = 0;
  263. nodes[nid].start = *addr;
  264. *addr += size;
  265. if (*addr >= max_addr) {
  266. *addr = max_addr;
  267. ret = -1;
  268. }
  269. nodes[nid].end = *addr;
  270. node_set(nid, node_possible_map);
  271. printk(KERN_INFO "Faking node %d at %016Lx-%016Lx (%LuMB)\n", nid,
  272. nodes[nid].start, nodes[nid].end,
  273. (nodes[nid].end - nodes[nid].start) >> 20);
  274. return ret;
  275. }
  276. /*
  277. * Splits num_nodes nodes up equally starting at node_start. The return value
  278. * is the number of nodes split up and addr is adjusted to be at the end of the
  279. * last node allocated.
  280. */
  281. static int __init split_nodes_equally(struct bootnode *nodes, u64 *addr,
  282. u64 max_addr, int node_start,
  283. int num_nodes)
  284. {
  285. unsigned int big;
  286. u64 size;
  287. int i;
  288. if (num_nodes <= 0)
  289. return -1;
  290. if (num_nodes > MAX_NUMNODES)
  291. num_nodes = MAX_NUMNODES;
  292. size = (max_addr - *addr - e820_hole_size(*addr, max_addr)) /
  293. num_nodes;
  294. /*
  295. * Calculate the number of big nodes that can be allocated as a result
  296. * of consolidating the leftovers.
  297. */
  298. big = ((size & ~FAKE_NODE_MIN_HASH_MASK) * num_nodes) /
  299. FAKE_NODE_MIN_SIZE;
  300. /* Round down to nearest FAKE_NODE_MIN_SIZE. */
  301. size &= FAKE_NODE_MIN_HASH_MASK;
  302. if (!size) {
  303. printk(KERN_ERR "Not enough memory for each node. "
  304. "NUMA emulation disabled.\n");
  305. return -1;
  306. }
  307. for (i = node_start; i < num_nodes + node_start; i++) {
  308. u64 end = *addr + size;
  309. if (i < big)
  310. end += FAKE_NODE_MIN_SIZE;
  311. /*
  312. * The final node can have the remaining system RAM. Other
  313. * nodes receive roughly the same amount of available pages.
  314. */
  315. if (i == num_nodes + node_start - 1)
  316. end = max_addr;
  317. else
  318. while (end - *addr - e820_hole_size(*addr, end) <
  319. size) {
  320. end += FAKE_NODE_MIN_SIZE;
  321. if (end > max_addr) {
  322. end = max_addr;
  323. break;
  324. }
  325. }
  326. if (setup_node_range(i, nodes, addr, end - *addr, max_addr) < 0)
  327. break;
  328. }
  329. return i - node_start + 1;
  330. }
  331. /*
  332. * Splits the remaining system RAM into chunks of size. The remaining memory is
  333. * always assigned to a final node and can be asymmetric. Returns the number of
  334. * nodes split.
  335. */
  336. static int __init split_nodes_by_size(struct bootnode *nodes, u64 *addr,
  337. u64 max_addr, int node_start, u64 size)
  338. {
  339. int i = node_start;
  340. size = (size << 20) & FAKE_NODE_MIN_HASH_MASK;
  341. while (!setup_node_range(i++, nodes, addr, size, max_addr))
  342. ;
  343. return i - node_start;
  344. }
  345. /*
  346. * Sets up the system RAM area from start_pfn to end_pfn according to the
  347. * numa=fake command-line option.
  348. */
  349. static int __init numa_emulation(unsigned long start_pfn, unsigned long end_pfn)
  350. {
  351. struct bootnode nodes[MAX_NUMNODES];
  352. u64 size, addr = start_pfn << PAGE_SHIFT;
  353. u64 max_addr = end_pfn << PAGE_SHIFT;
  354. int num_nodes = 0, num = 0, coeff_flag, coeff = -1, i;
  355. memset(&nodes, 0, sizeof(nodes));
  356. /*
  357. * If the numa=fake command-line is just a single number N, split the
  358. * system RAM into N fake nodes.
  359. */
  360. if (!strchr(cmdline, '*') && !strchr(cmdline, ',')) {
  361. long n = simple_strtol(cmdline, NULL, 0);
  362. num_nodes = split_nodes_equally(nodes, &addr, max_addr, 0, n);
  363. if (num_nodes < 0)
  364. return num_nodes;
  365. goto out;
  366. }
  367. /* Parse the command line. */
  368. for (coeff_flag = 0; ; cmdline++) {
  369. if (*cmdline && isdigit(*cmdline)) {
  370. num = num * 10 + *cmdline - '0';
  371. continue;
  372. }
  373. if (*cmdline == '*') {
  374. if (num > 0)
  375. coeff = num;
  376. coeff_flag = 1;
  377. }
  378. if (!*cmdline || *cmdline == ',') {
  379. if (!coeff_flag)
  380. coeff = 1;
  381. /*
  382. * Round down to the nearest FAKE_NODE_MIN_SIZE.
  383. * Command-line coefficients are in megabytes.
  384. */
  385. size = ((u64)num << 20) & FAKE_NODE_MIN_HASH_MASK;
  386. if (size)
  387. for (i = 0; i < coeff; i++, num_nodes++)
  388. if (setup_node_range(num_nodes, nodes,
  389. &addr, size, max_addr) < 0)
  390. goto done;
  391. if (!*cmdline)
  392. break;
  393. coeff_flag = 0;
  394. coeff = -1;
  395. }
  396. num = 0;
  397. }
  398. done:
  399. if (!num_nodes)
  400. return -1;
  401. /* Fill remainder of system RAM, if appropriate. */
  402. if (addr < max_addr) {
  403. if (coeff_flag && coeff < 0) {
  404. /* Split remaining nodes into num-sized chunks */
  405. num_nodes += split_nodes_by_size(nodes, &addr, max_addr,
  406. num_nodes, num);
  407. goto out;
  408. }
  409. switch (*(cmdline - 1)) {
  410. case '*':
  411. /* Split remaining nodes into coeff chunks */
  412. if (coeff <= 0)
  413. break;
  414. num_nodes += split_nodes_equally(nodes, &addr, max_addr,
  415. num_nodes, coeff);
  416. break;
  417. case ',':
  418. /* Do not allocate remaining system RAM */
  419. break;
  420. default:
  421. /* Give one final node */
  422. setup_node_range(num_nodes, nodes, &addr,
  423. max_addr - addr, max_addr);
  424. num_nodes++;
  425. }
  426. }
  427. out:
  428. memnode_shift = compute_hash_shift(nodes, num_nodes);
  429. if (memnode_shift < 0) {
  430. memnode_shift = 0;
  431. printk(KERN_ERR "No NUMA hash function found. NUMA emulation "
  432. "disabled.\n");
  433. return -1;
  434. }
  435. /*
  436. * We need to vacate all active ranges that may have been registered by
  437. * SRAT and set acpi_numa to -1 so that srat_disabled() always returns
  438. * true. NUMA emulation has succeeded so we will not scan ACPI nodes.
  439. */
  440. remove_all_active_ranges();
  441. #ifdef CONFIG_ACPI_NUMA
  442. acpi_numa = -1;
  443. #endif
  444. for_each_node_mask(i, node_possible_map) {
  445. e820_register_active_regions(i, nodes[i].start >> PAGE_SHIFT,
  446. nodes[i].end >> PAGE_SHIFT);
  447. setup_node_bootmem(i, nodes[i].start, nodes[i].end);
  448. }
  449. acpi_fake_nodes(nodes, num_nodes);
  450. numa_init_array();
  451. return 0;
  452. }
  453. #endif /* CONFIG_NUMA_EMU */
  454. void __init numa_initmem_init(unsigned long start_pfn, unsigned long end_pfn)
  455. {
  456. int i;
  457. nodes_clear(node_possible_map);
  458. #ifdef CONFIG_NUMA_EMU
  459. if (cmdline && !numa_emulation(start_pfn, end_pfn))
  460. return;
  461. nodes_clear(node_possible_map);
  462. #endif
  463. #ifdef CONFIG_ACPI_NUMA
  464. if (!numa_off && !acpi_scan_nodes(start_pfn << PAGE_SHIFT,
  465. end_pfn << PAGE_SHIFT))
  466. return;
  467. nodes_clear(node_possible_map);
  468. #endif
  469. #ifdef CONFIG_K8_NUMA
  470. if (!numa_off && !k8_scan_nodes(start_pfn<<PAGE_SHIFT,
  471. end_pfn<<PAGE_SHIFT))
  472. return;
  473. nodes_clear(node_possible_map);
  474. #endif
  475. printk(KERN_INFO "%s\n",
  476. numa_off ? "NUMA turned off" : "No NUMA configuration found");
  477. printk(KERN_INFO "Faking a node at %016lx-%016lx\n",
  478. start_pfn << PAGE_SHIFT,
  479. end_pfn << PAGE_SHIFT);
  480. /* setup dummy node covering all memory */
  481. memnode_shift = 63;
  482. memnodemap = memnode.embedded_map;
  483. memnodemap[0] = 0;
  484. nodes_clear(node_online_map);
  485. node_set_online(0);
  486. node_set(0, node_possible_map);
  487. for (i = 0; i < NR_CPUS; i++)
  488. numa_set_node(i, 0);
  489. /* cpumask_of_cpu() may not be available during early startup */
  490. memset(&node_to_cpumask_map[0], 0, sizeof(node_to_cpumask_map[0]));
  491. cpu_set(0, node_to_cpumask_map[0]);
  492. e820_register_active_regions(0, start_pfn, end_pfn);
  493. setup_node_bootmem(0, start_pfn << PAGE_SHIFT, end_pfn << PAGE_SHIFT);
  494. }
  495. __cpuinit void numa_add_cpu(int cpu)
  496. {
  497. set_bit(cpu, (unsigned long *)&node_to_cpumask_map[cpu_to_node(cpu)]);
  498. }
  499. void __cpuinit numa_set_node(int cpu, int node)
  500. {
  501. u16 *cpu_to_node_map = x86_cpu_to_node_map_early_ptr;
  502. cpu_pda(cpu)->nodenumber = node;
  503. if(cpu_to_node_map)
  504. cpu_to_node_map[cpu] = node;
  505. else if(per_cpu_offset(cpu))
  506. per_cpu(x86_cpu_to_node_map, cpu) = node;
  507. else
  508. Dprintk(KERN_INFO "Setting node for non-present cpu %d\n", cpu);
  509. }
  510. unsigned long __init numa_free_all_bootmem(void)
  511. {
  512. unsigned long pages = 0;
  513. int i;
  514. for_each_online_node(i)
  515. pages += free_all_bootmem_node(NODE_DATA(i));
  516. return pages;
  517. }
  518. void __init paging_init(void)
  519. {
  520. unsigned long max_zone_pfns[MAX_NR_ZONES];
  521. int i;
  522. memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
  523. max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
  524. max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
  525. max_zone_pfns[ZONE_NORMAL] = end_pfn;
  526. sparse_memory_present_with_active_regions(MAX_NUMNODES);
  527. sparse_init();
  528. for_each_online_node(i)
  529. flat_setup_node_zones(i);
  530. free_area_init_nodes(max_zone_pfns);
  531. }
  532. static __init int numa_setup(char *opt)
  533. {
  534. if (!opt)
  535. return -EINVAL;
  536. if (!strncmp(opt, "off", 3))
  537. numa_off = 1;
  538. #ifdef CONFIG_NUMA_EMU
  539. if (!strncmp(opt, "fake=", 5))
  540. cmdline = opt + 5;
  541. #endif
  542. #ifdef CONFIG_ACPI_NUMA
  543. if (!strncmp(opt, "noacpi", 6))
  544. acpi_numa = -1;
  545. if (!strncmp(opt, "hotadd=", 7))
  546. hotadd_percent = simple_strtoul(opt+7, NULL, 10);
  547. #endif
  548. return 0;
  549. }
  550. early_param("numa", numa_setup);
  551. /*
  552. * Setup early cpu_to_node.
  553. *
  554. * Populate cpu_to_node[] only if x86_cpu_to_apicid[],
  555. * and apicid_to_node[] tables have valid entries for a CPU.
  556. * This means we skip cpu_to_node[] initialisation for NUMA
  557. * emulation and faking node case (when running a kernel compiled
  558. * for NUMA on a non NUMA box), which is OK as cpu_to_node[]
  559. * is already initialized in a round robin manner at numa_init_array,
  560. * prior to this call, and this initialization is good enough
  561. * for the fake NUMA cases.
  562. */
  563. void __init init_cpu_to_node(void)
  564. {
  565. int i;
  566. for (i = 0; i < NR_CPUS; i++) {
  567. u16 apicid = x86_cpu_to_apicid_init[i];
  568. if (apicid == BAD_APICID)
  569. continue;
  570. if (apicid_to_node[apicid] == NUMA_NO_NODE)
  571. continue;
  572. numa_set_node(i, apicid_to_node[apicid]);
  573. }
  574. }