1 /* 2 * pSeries NUMA support 3 * 4 * Copyright (C) 2002 Anton Blanchard <anton@au.ibm.com>, IBM 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 9 * 2 of the License, or (at your option) any later version. 10 */ 11 #include <linux/threads.h> 12 #include <linux/bootmem.h> 13 #include <linux/init.h> 14 #include <linux/mm.h> 15 #include <linux/mmzone.h> 16 #include <linux/export.h> 17 #include <linux/nodemask.h> 18 #include <linux/cpu.h> 19 #include <linux/notifier.h> 20 #include <linux/memblock.h> 21 #include <linux/of.h> 22 #include <linux/pfn.h> 23 #include <linux/cpuset.h> 24 #include <linux/node.h> 25 #include <linux/stop_machine.h> 26 #include <linux/proc_fs.h> 27 #include <linux/seq_file.h> 28 #include <linux/uaccess.h> 29 #include <linux/slab.h> 30 #include <asm/cputhreads.h> 31 #include <asm/sparsemem.h> 32 #include <asm/prom.h> 33 #include <asm/smp.h> 34 #include <asm/cputhreads.h> 35 #include <asm/topology.h> 36 #include <asm/firmware.h> 37 #include <asm/paca.h> 38 #include <asm/hvcall.h> 39 #include <asm/setup.h> 40 #include <asm/vdso.h> 41 42 static int numa_enabled = 1; 43 44 static char *cmdline __initdata; 45 46 static int numa_debug; 47 #define dbg(args...) if (numa_debug) { printk(KERN_INFO args); } 48 49 int numa_cpu_lookup_table[NR_CPUS]; 50 cpumask_var_t node_to_cpumask_map[MAX_NUMNODES]; 51 struct pglist_data *node_data[MAX_NUMNODES]; 52 53 EXPORT_SYMBOL(numa_cpu_lookup_table); 54 EXPORT_SYMBOL(node_to_cpumask_map); 55 EXPORT_SYMBOL(node_data); 56 57 static int min_common_depth; 58 static int n_mem_addr_cells, n_mem_size_cells; 59 static int form1_affinity; 60 61 #define MAX_DISTANCE_REF_POINTS 4 62 static int distance_ref_points_depth; 63 static const __be32 *distance_ref_points; 64 static int distance_lookup_table[MAX_NUMNODES][MAX_DISTANCE_REF_POINTS]; 65 66 /* 67 * Allocate node_to_cpumask_map based on number of available nodes 68 * Requires node_possible_map to be valid. 69 * 70 * Note: cpumask_of_node() is not valid until after this is done. 71 */ 72 static void __init setup_node_to_cpumask_map(void) 73 { 74 unsigned int node; 75 76 /* setup nr_node_ids if not done yet */ 77 if (nr_node_ids == MAX_NUMNODES) 78 setup_nr_node_ids(); 79 80 /* allocate the map */ 81 for (node = 0; node < nr_node_ids; node++) 82 alloc_bootmem_cpumask_var(&node_to_cpumask_map[node]); 83 84 /* cpumask_of_node() will now work */ 85 dbg("Node to cpumask map for %d nodes\n", nr_node_ids); 86 } 87 88 static int __init fake_numa_create_new_node(unsigned long end_pfn, 89 unsigned int *nid) 90 { 91 unsigned long long mem; 92 char *p = cmdline; 93 static unsigned int fake_nid; 94 static unsigned long long curr_boundary; 95 96 /* 97 * Modify node id, iff we started creating NUMA nodes 98 * We want to continue from where we left of the last time 99 */ 100 if (fake_nid) 101 *nid = fake_nid; 102 /* 103 * In case there are no more arguments to parse, the 104 * node_id should be the same as the last fake node id 105 * (we've handled this above). 106 */ 107 if (!p) 108 return 0; 109 110 mem = memparse(p, &p); 111 if (!mem) 112 return 0; 113 114 if (mem < curr_boundary) 115 return 0; 116 117 curr_boundary = mem; 118 119 if ((end_pfn << PAGE_SHIFT) > mem) { 120 /* 121 * Skip commas and spaces 122 */ 123 while (*p == ',' || *p == ' ' || *p == '\t') 124 p++; 125 126 cmdline = p; 127 fake_nid++; 128 *nid = fake_nid; 129 dbg("created new fake_node with id %d\n", fake_nid); 130 return 1; 131 } 132 return 0; 133 } 134 135 /* 136 * get_node_active_region - Return active region containing pfn 137 * Active range returned is empty if none found. 138 * @pfn: The page to return the region for 139 * @node_ar: Returned set to the active region containing @pfn 140 */ 141 static void __init get_node_active_region(unsigned long pfn, 142 struct node_active_region *node_ar) 143 { 144 unsigned long start_pfn, end_pfn; 145 int i, nid; 146 147 for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) { 148 if (pfn >= start_pfn && pfn < end_pfn) { 149 node_ar->nid = nid; 150 node_ar->start_pfn = start_pfn; 151 node_ar->end_pfn = end_pfn; 152 break; 153 } 154 } 155 } 156 157 static void reset_numa_cpu_lookup_table(void) 158 { 159 unsigned int cpu; 160 161 for_each_possible_cpu(cpu) 162 numa_cpu_lookup_table[cpu] = -1; 163 } 164 165 static void update_numa_cpu_lookup_table(unsigned int cpu, int node) 166 { 167 numa_cpu_lookup_table[cpu] = node; 168 } 169 170 static void map_cpu_to_node(int cpu, int node) 171 { 172 update_numa_cpu_lookup_table(cpu, node); 173 174 dbg("adding cpu %d to node %d\n", cpu, node); 175 176 if (!(cpumask_test_cpu(cpu, node_to_cpumask_map[node]))) 177 cpumask_set_cpu(cpu, node_to_cpumask_map[node]); 178 } 179 180 #if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_PPC_SPLPAR) 181 static void unmap_cpu_from_node(unsigned long cpu) 182 { 183 int node = numa_cpu_lookup_table[cpu]; 184 185 dbg("removing cpu %lu from node %d\n", cpu, node); 186 187 if (cpumask_test_cpu(cpu, node_to_cpumask_map[node])) { 188 cpumask_clear_cpu(cpu, node_to_cpumask_map[node]); 189 } else { 190 printk(KERN_ERR "WARNING: cpu %lu not found in node %d\n", 191 cpu, node); 192 } 193 } 194 #endif /* CONFIG_HOTPLUG_CPU || CONFIG_PPC_SPLPAR */ 195 196 /* must hold reference to node during call */ 197 static const __be32 *of_get_associativity(struct device_node *dev) 198 { 199 return of_get_property(dev, "ibm,associativity", NULL); 200 } 201 202 /* 203 * Returns the property linux,drconf-usable-memory if 204 * it exists (the property exists only in kexec/kdump kernels, 205 * added by kexec-tools) 206 */ 207 static const __be32 *of_get_usable_memory(struct device_node *memory) 208 { 209 const __be32 *prop; 210 u32 len; 211 prop = of_get_property(memory, "linux,drconf-usable-memory", &len); 212 if (!prop || len < sizeof(unsigned int)) 213 return NULL; 214 return prop; 215 } 216 217 int __node_distance(int a, int b) 218 { 219 int i; 220 int distance = LOCAL_DISTANCE; 221 222 if (!form1_affinity) 223 return ((a == b) ? LOCAL_DISTANCE : REMOTE_DISTANCE); 224 225 for (i = 0; i < distance_ref_points_depth; i++) { 226 if (distance_lookup_table[a][i] == distance_lookup_table[b][i]) 227 break; 228 229 /* Double the distance for each NUMA level */ 230 distance *= 2; 231 } 232 233 return distance; 234 } 235 236 static void initialize_distance_lookup_table(int nid, 237 const __be32 *associativity) 238 { 239 int i; 240 241 if (!form1_affinity) 242 return; 243 244 for (i = 0; i < distance_ref_points_depth; i++) { 245 const __be32 *entry; 246 247 entry = &associativity[be32_to_cpu(distance_ref_points[i])]; 248 distance_lookup_table[nid][i] = of_read_number(entry, 1); 249 } 250 } 251 252 /* Returns nid in the range [0..MAX_NUMNODES-1], or -1 if no useful numa 253 * info is found. 254 */ 255 static int associativity_to_nid(const __be32 *associativity) 256 { 257 int nid = -1; 258 259 if (min_common_depth == -1) 260 goto out; 261 262 if (of_read_number(associativity, 1) >= min_common_depth) 263 nid = of_read_number(&associativity[min_common_depth], 1); 264 265 /* POWER4 LPAR uses 0xffff as invalid node */ 266 if (nid == 0xffff || nid >= MAX_NUMNODES) 267 nid = -1; 268 269 if (nid > 0 && 270 of_read_number(associativity, 1) >= distance_ref_points_depth) 271 initialize_distance_lookup_table(nid, associativity); 272 273 out: 274 return nid; 275 } 276 277 /* Returns the nid associated with the given device tree node, 278 * or -1 if not found. 279 */ 280 static int of_node_to_nid_single(struct device_node *device) 281 { 282 int nid = -1; 283 const __be32 *tmp; 284 285 tmp = of_get_associativity(device); 286 if (tmp) 287 nid = associativity_to_nid(tmp); 288 return nid; 289 } 290 291 /* Walk the device tree upwards, looking for an associativity id */ 292 int of_node_to_nid(struct device_node *device) 293 { 294 struct device_node *tmp; 295 int nid = -1; 296 297 of_node_get(device); 298 while (device) { 299 nid = of_node_to_nid_single(device); 300 if (nid != -1) 301 break; 302 303 tmp = device; 304 device = of_get_parent(tmp); 305 of_node_put(tmp); 306 } 307 of_node_put(device); 308 309 return nid; 310 } 311 EXPORT_SYMBOL_GPL(of_node_to_nid); 312 313 static int __init find_min_common_depth(void) 314 { 315 int depth; 316 struct device_node *root; 317 318 if (firmware_has_feature(FW_FEATURE_OPAL)) 319 root = of_find_node_by_path("/ibm,opal"); 320 else 321 root = of_find_node_by_path("/rtas"); 322 if (!root) 323 root = of_find_node_by_path("/"); 324 325 /* 326 * This property is a set of 32-bit integers, each representing 327 * an index into the ibm,associativity nodes. 328 * 329 * With form 0 affinity the first integer is for an SMP configuration 330 * (should be all 0's) and the second is for a normal NUMA 331 * configuration. We have only one level of NUMA. 332 * 333 * With form 1 affinity the first integer is the most significant 334 * NUMA boundary and the following are progressively less significant 335 * boundaries. There can be more than one level of NUMA. 336 */ 337 distance_ref_points = of_get_property(root, 338 "ibm,associativity-reference-points", 339 &distance_ref_points_depth); 340 341 if (!distance_ref_points) { 342 dbg("NUMA: ibm,associativity-reference-points not found.\n"); 343 goto err; 344 } 345 346 distance_ref_points_depth /= sizeof(int); 347 348 if (firmware_has_feature(FW_FEATURE_OPAL) || 349 firmware_has_feature(FW_FEATURE_TYPE1_AFFINITY)) { 350 dbg("Using form 1 affinity\n"); 351 form1_affinity = 1; 352 } 353 354 if (form1_affinity) { 355 depth = of_read_number(distance_ref_points, 1); 356 } else { 357 if (distance_ref_points_depth < 2) { 358 printk(KERN_WARNING "NUMA: " 359 "short ibm,associativity-reference-points\n"); 360 goto err; 361 } 362 363 depth = of_read_number(&distance_ref_points[1], 1); 364 } 365 366 /* 367 * Warn and cap if the hardware supports more than 368 * MAX_DISTANCE_REF_POINTS domains. 369 */ 370 if (distance_ref_points_depth > MAX_DISTANCE_REF_POINTS) { 371 printk(KERN_WARNING "NUMA: distance array capped at " 372 "%d entries\n", MAX_DISTANCE_REF_POINTS); 373 distance_ref_points_depth = MAX_DISTANCE_REF_POINTS; 374 } 375 376 of_node_put(root); 377 return depth; 378 379 err: 380 of_node_put(root); 381 return -1; 382 } 383 384 static void __init get_n_mem_cells(int *n_addr_cells, int *n_size_cells) 385 { 386 struct device_node *memory = NULL; 387 388 memory = of_find_node_by_type(memory, "memory"); 389 if (!memory) 390 panic("numa.c: No memory nodes found!"); 391 392 *n_addr_cells = of_n_addr_cells(memory); 393 *n_size_cells = of_n_size_cells(memory); 394 of_node_put(memory); 395 } 396 397 static unsigned long read_n_cells(int n, const __be32 **buf) 398 { 399 unsigned long result = 0; 400 401 while (n--) { 402 result = (result << 32) | of_read_number(*buf, 1); 403 (*buf)++; 404 } 405 return result; 406 } 407 408 /* 409 * Read the next memblock list entry from the ibm,dynamic-memory property 410 * and return the information in the provided of_drconf_cell structure. 411 */ 412 static void read_drconf_cell(struct of_drconf_cell *drmem, const __be32 **cellp) 413 { 414 const __be32 *cp; 415 416 drmem->base_addr = read_n_cells(n_mem_addr_cells, cellp); 417 418 cp = *cellp; 419 drmem->drc_index = of_read_number(cp, 1); 420 drmem->reserved = of_read_number(&cp[1], 1); 421 drmem->aa_index = of_read_number(&cp[2], 1); 422 drmem->flags = of_read_number(&cp[3], 1); 423 424 *cellp = cp + 4; 425 } 426 427 /* 428 * Retrieve and validate the ibm,dynamic-memory property of the device tree. 429 * 430 * The layout of the ibm,dynamic-memory property is a number N of memblock 431 * list entries followed by N memblock list entries. Each memblock list entry 432 * contains information as laid out in the of_drconf_cell struct above. 433 */ 434 static int of_get_drconf_memory(struct device_node *memory, const __be32 **dm) 435 { 436 const __be32 *prop; 437 u32 len, entries; 438 439 prop = of_get_property(memory, "ibm,dynamic-memory", &len); 440 if (!prop || len < sizeof(unsigned int)) 441 return 0; 442 443 entries = of_read_number(prop++, 1); 444 445 /* Now that we know the number of entries, revalidate the size 446 * of the property read in to ensure we have everything 447 */ 448 if (len < (entries * (n_mem_addr_cells + 4) + 1) * sizeof(unsigned int)) 449 return 0; 450 451 *dm = prop; 452 return entries; 453 } 454 455 /* 456 * Retrieve and validate the ibm,lmb-size property for drconf memory 457 * from the device tree. 458 */ 459 static u64 of_get_lmb_size(struct device_node *memory) 460 { 461 const __be32 *prop; 462 u32 len; 463 464 prop = of_get_property(memory, "ibm,lmb-size", &len); 465 if (!prop || len < sizeof(unsigned int)) 466 return 0; 467 468 return read_n_cells(n_mem_size_cells, &prop); 469 } 470 471 struct assoc_arrays { 472 u32 n_arrays; 473 u32 array_sz; 474 const __be32 *arrays; 475 }; 476 477 /* 478 * Retrieve and validate the list of associativity arrays for drconf 479 * memory from the ibm,associativity-lookup-arrays property of the 480 * device tree.. 481 * 482 * The layout of the ibm,associativity-lookup-arrays property is a number N 483 * indicating the number of associativity arrays, followed by a number M 484 * indicating the size of each associativity array, followed by a list 485 * of N associativity arrays. 486 */ 487 static int of_get_assoc_arrays(struct device_node *memory, 488 struct assoc_arrays *aa) 489 { 490 const __be32 *prop; 491 u32 len; 492 493 prop = of_get_property(memory, "ibm,associativity-lookup-arrays", &len); 494 if (!prop || len < 2 * sizeof(unsigned int)) 495 return -1; 496 497 aa->n_arrays = of_read_number(prop++, 1); 498 aa->array_sz = of_read_number(prop++, 1); 499 500 /* Now that we know the number of arrays and size of each array, 501 * revalidate the size of the property read in. 502 */ 503 if (len < (aa->n_arrays * aa->array_sz + 2) * sizeof(unsigned int)) 504 return -1; 505 506 aa->arrays = prop; 507 return 0; 508 } 509 510 /* 511 * This is like of_node_to_nid_single() for memory represented in the 512 * ibm,dynamic-reconfiguration-memory node. 513 */ 514 static int of_drconf_to_nid_single(struct of_drconf_cell *drmem, 515 struct assoc_arrays *aa) 516 { 517 int default_nid = 0; 518 int nid = default_nid; 519 int index; 520 521 if (min_common_depth > 0 && min_common_depth <= aa->array_sz && 522 !(drmem->flags & DRCONF_MEM_AI_INVALID) && 523 drmem->aa_index < aa->n_arrays) { 524 index = drmem->aa_index * aa->array_sz + min_common_depth - 1; 525 nid = of_read_number(&aa->arrays[index], 1); 526 527 if (nid == 0xffff || nid >= MAX_NUMNODES) 528 nid = default_nid; 529 } 530 531 return nid; 532 } 533 534 /* 535 * Figure out to which domain a cpu belongs and stick it there. 536 * Return the id of the domain used. 537 */ 538 static int numa_setup_cpu(unsigned long lcpu) 539 { 540 int nid; 541 struct device_node *cpu; 542 543 /* 544 * If a valid cpu-to-node mapping is already available, use it 545 * directly instead of querying the firmware, since it represents 546 * the most recent mapping notified to us by the platform (eg: VPHN). 547 */ 548 if ((nid = numa_cpu_lookup_table[lcpu]) >= 0) { 549 map_cpu_to_node(lcpu, nid); 550 return nid; 551 } 552 553 cpu = of_get_cpu_node(lcpu, NULL); 554 555 if (!cpu) { 556 WARN_ON(1); 557 nid = 0; 558 goto out; 559 } 560 561 nid = of_node_to_nid_single(cpu); 562 563 if (nid < 0 || !node_online(nid)) 564 nid = first_online_node; 565 out: 566 map_cpu_to_node(lcpu, nid); 567 568 of_node_put(cpu); 569 570 return nid; 571 } 572 573 static void verify_cpu_node_mapping(int cpu, int node) 574 { 575 int base, sibling, i; 576 577 /* Verify that all the threads in the core belong to the same node */ 578 base = cpu_first_thread_sibling(cpu); 579 580 for (i = 0; i < threads_per_core; i++) { 581 sibling = base + i; 582 583 if (sibling == cpu || cpu_is_offline(sibling)) 584 continue; 585 586 if (cpu_to_node(sibling) != node) { 587 WARN(1, "CPU thread siblings %d and %d don't belong" 588 " to the same node!\n", cpu, sibling); 589 break; 590 } 591 } 592 } 593 594 static int cpu_numa_callback(struct notifier_block *nfb, unsigned long action, 595 void *hcpu) 596 { 597 unsigned long lcpu = (unsigned long)hcpu; 598 int ret = NOTIFY_DONE, nid; 599 600 switch (action) { 601 case CPU_UP_PREPARE: 602 case CPU_UP_PREPARE_FROZEN: 603 nid = numa_setup_cpu(lcpu); 604 verify_cpu_node_mapping((int)lcpu, nid); 605 ret = NOTIFY_OK; 606 break; 607 #ifdef CONFIG_HOTPLUG_CPU 608 case CPU_DEAD: 609 case CPU_DEAD_FROZEN: 610 case CPU_UP_CANCELED: 611 case CPU_UP_CANCELED_FROZEN: 612 unmap_cpu_from_node(lcpu); 613 break; 614 ret = NOTIFY_OK; 615 #endif 616 } 617 return ret; 618 } 619 620 /* 621 * Check and possibly modify a memory region to enforce the memory limit. 622 * 623 * Returns the size the region should have to enforce the memory limit. 624 * This will either be the original value of size, a truncated value, 625 * or zero. If the returned value of size is 0 the region should be 626 * discarded as it lies wholly above the memory limit. 627 */ 628 static unsigned long __init numa_enforce_memory_limit(unsigned long start, 629 unsigned long size) 630 { 631 /* 632 * We use memblock_end_of_DRAM() in here instead of memory_limit because 633 * we've already adjusted it for the limit and it takes care of 634 * having memory holes below the limit. Also, in the case of 635 * iommu_is_off, memory_limit is not set but is implicitly enforced. 636 */ 637 638 if (start + size <= memblock_end_of_DRAM()) 639 return size; 640 641 if (start >= memblock_end_of_DRAM()) 642 return 0; 643 644 return memblock_end_of_DRAM() - start; 645 } 646 647 /* 648 * Reads the counter for a given entry in 649 * linux,drconf-usable-memory property 650 */ 651 static inline int __init read_usm_ranges(const __be32 **usm) 652 { 653 /* 654 * For each lmb in ibm,dynamic-memory a corresponding 655 * entry in linux,drconf-usable-memory property contains 656 * a counter followed by that many (base, size) duple. 657 * read the counter from linux,drconf-usable-memory 658 */ 659 return read_n_cells(n_mem_size_cells, usm); 660 } 661 662 /* 663 * Extract NUMA information from the ibm,dynamic-reconfiguration-memory 664 * node. This assumes n_mem_{addr,size}_cells have been set. 665 */ 666 static void __init parse_drconf_memory(struct device_node *memory) 667 { 668 const __be32 *uninitialized_var(dm), *usm; 669 unsigned int n, rc, ranges, is_kexec_kdump = 0; 670 unsigned long lmb_size, base, size, sz; 671 int nid; 672 struct assoc_arrays aa = { .arrays = NULL }; 673 674 n = of_get_drconf_memory(memory, &dm); 675 if (!n) 676 return; 677 678 lmb_size = of_get_lmb_size(memory); 679 if (!lmb_size) 680 return; 681 682 rc = of_get_assoc_arrays(memory, &aa); 683 if (rc) 684 return; 685 686 /* check if this is a kexec/kdump kernel */ 687 usm = of_get_usable_memory(memory); 688 if (usm != NULL) 689 is_kexec_kdump = 1; 690 691 for (; n != 0; --n) { 692 struct of_drconf_cell drmem; 693 694 read_drconf_cell(&drmem, &dm); 695 696 /* skip this block if the reserved bit is set in flags (0x80) 697 or if the block is not assigned to this partition (0x8) */ 698 if ((drmem.flags & DRCONF_MEM_RESERVED) 699 || !(drmem.flags & DRCONF_MEM_ASSIGNED)) 700 continue; 701 702 base = drmem.base_addr; 703 size = lmb_size; 704 ranges = 1; 705 706 if (is_kexec_kdump) { 707 ranges = read_usm_ranges(&usm); 708 if (!ranges) /* there are no (base, size) duple */ 709 continue; 710 } 711 do { 712 if (is_kexec_kdump) { 713 base = read_n_cells(n_mem_addr_cells, &usm); 714 size = read_n_cells(n_mem_size_cells, &usm); 715 } 716 nid = of_drconf_to_nid_single(&drmem, &aa); 717 fake_numa_create_new_node( 718 ((base + size) >> PAGE_SHIFT), 719 &nid); 720 node_set_online(nid); 721 sz = numa_enforce_memory_limit(base, size); 722 if (sz) 723 memblock_set_node(base, sz, 724 &memblock.memory, nid); 725 } while (--ranges); 726 } 727 } 728 729 static int __init parse_numa_properties(void) 730 { 731 struct device_node *memory; 732 int default_nid = 0; 733 unsigned long i; 734 735 if (numa_enabled == 0) { 736 printk(KERN_WARNING "NUMA disabled by user\n"); 737 return -1; 738 } 739 740 min_common_depth = find_min_common_depth(); 741 742 if (min_common_depth < 0) 743 return min_common_depth; 744 745 dbg("NUMA associativity depth for CPU/Memory: %d\n", min_common_depth); 746 747 /* 748 * Even though we connect cpus to numa domains later in SMP 749 * init, we need to know the node ids now. This is because 750 * each node to be onlined must have NODE_DATA etc backing it. 751 */ 752 for_each_present_cpu(i) { 753 struct device_node *cpu; 754 int nid; 755 756 cpu = of_get_cpu_node(i, NULL); 757 BUG_ON(!cpu); 758 nid = of_node_to_nid_single(cpu); 759 of_node_put(cpu); 760 761 /* 762 * Don't fall back to default_nid yet -- we will plug 763 * cpus into nodes once the memory scan has discovered 764 * the topology. 765 */ 766 if (nid < 0) 767 continue; 768 node_set_online(nid); 769 } 770 771 get_n_mem_cells(&n_mem_addr_cells, &n_mem_size_cells); 772 773 for_each_node_by_type(memory, "memory") { 774 unsigned long start; 775 unsigned long size; 776 int nid; 777 int ranges; 778 const __be32 *memcell_buf; 779 unsigned int len; 780 781 memcell_buf = of_get_property(memory, 782 "linux,usable-memory", &len); 783 if (!memcell_buf || len <= 0) 784 memcell_buf = of_get_property(memory, "reg", &len); 785 if (!memcell_buf || len <= 0) 786 continue; 787 788 /* ranges in cell */ 789 ranges = (len >> 2) / (n_mem_addr_cells + n_mem_size_cells); 790 new_range: 791 /* these are order-sensitive, and modify the buffer pointer */ 792 start = read_n_cells(n_mem_addr_cells, &memcell_buf); 793 size = read_n_cells(n_mem_size_cells, &memcell_buf); 794 795 /* 796 * Assumption: either all memory nodes or none will 797 * have associativity properties. If none, then 798 * everything goes to default_nid. 799 */ 800 nid = of_node_to_nid_single(memory); 801 if (nid < 0) 802 nid = default_nid; 803 804 fake_numa_create_new_node(((start + size) >> PAGE_SHIFT), &nid); 805 node_set_online(nid); 806 807 if (!(size = numa_enforce_memory_limit(start, size))) { 808 if (--ranges) 809 goto new_range; 810 else 811 continue; 812 } 813 814 memblock_set_node(start, size, &memblock.memory, nid); 815 816 if (--ranges) 817 goto new_range; 818 } 819 820 /* 821 * Now do the same thing for each MEMBLOCK listed in the 822 * ibm,dynamic-memory property in the 823 * ibm,dynamic-reconfiguration-memory node. 824 */ 825 memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory"); 826 if (memory) 827 parse_drconf_memory(memory); 828 829 return 0; 830 } 831 832 static void __init setup_nonnuma(void) 833 { 834 unsigned long top_of_ram = memblock_end_of_DRAM(); 835 unsigned long total_ram = memblock_phys_mem_size(); 836 unsigned long start_pfn, end_pfn; 837 unsigned int nid = 0; 838 struct memblock_region *reg; 839 840 printk(KERN_DEBUG "Top of RAM: 0x%lx, Total RAM: 0x%lx\n", 841 top_of_ram, total_ram); 842 printk(KERN_DEBUG "Memory hole size: %ldMB\n", 843 (top_of_ram - total_ram) >> 20); 844 845 for_each_memblock(memory, reg) { 846 start_pfn = memblock_region_memory_base_pfn(reg); 847 end_pfn = memblock_region_memory_end_pfn(reg); 848 849 fake_numa_create_new_node(end_pfn, &nid); 850 memblock_set_node(PFN_PHYS(start_pfn), 851 PFN_PHYS(end_pfn - start_pfn), 852 &memblock.memory, nid); 853 node_set_online(nid); 854 } 855 } 856 857 void __init dump_numa_cpu_topology(void) 858 { 859 unsigned int node; 860 unsigned int cpu, count; 861 862 if (min_common_depth == -1 || !numa_enabled) 863 return; 864 865 for_each_online_node(node) { 866 printk(KERN_DEBUG "Node %d CPUs:", node); 867 868 count = 0; 869 /* 870 * If we used a CPU iterator here we would miss printing 871 * the holes in the cpumap. 872 */ 873 for (cpu = 0; cpu < nr_cpu_ids; cpu++) { 874 if (cpumask_test_cpu(cpu, 875 node_to_cpumask_map[node])) { 876 if (count == 0) 877 printk(" %u", cpu); 878 ++count; 879 } else { 880 if (count > 1) 881 printk("-%u", cpu - 1); 882 count = 0; 883 } 884 } 885 886 if (count > 1) 887 printk("-%u", nr_cpu_ids - 1); 888 printk("\n"); 889 } 890 } 891 892 static void __init dump_numa_memory_topology(void) 893 { 894 unsigned int node; 895 unsigned int count; 896 897 if (min_common_depth == -1 || !numa_enabled) 898 return; 899 900 for_each_online_node(node) { 901 unsigned long i; 902 903 printk(KERN_DEBUG "Node %d Memory:", node); 904 905 count = 0; 906 907 for (i = 0; i < memblock_end_of_DRAM(); 908 i += (1 << SECTION_SIZE_BITS)) { 909 if (early_pfn_to_nid(i >> PAGE_SHIFT) == node) { 910 if (count == 0) 911 printk(" 0x%lx", i); 912 ++count; 913 } else { 914 if (count > 0) 915 printk("-0x%lx", i); 916 count = 0; 917 } 918 } 919 920 if (count > 0) 921 printk("-0x%lx", i); 922 printk("\n"); 923 } 924 } 925 926 /* 927 * Allocate some memory, satisfying the memblock or bootmem allocator where 928 * required. nid is the preferred node and end is the physical address of 929 * the highest address in the node. 930 * 931 * Returns the virtual address of the memory. 932 */ 933 static void __init *careful_zallocation(int nid, unsigned long size, 934 unsigned long align, 935 unsigned long end_pfn) 936 { 937 void *ret; 938 int new_nid; 939 unsigned long ret_paddr; 940 941 ret_paddr = __memblock_alloc_base(size, align, end_pfn << PAGE_SHIFT); 942 943 /* retry over all memory */ 944 if (!ret_paddr) 945 ret_paddr = __memblock_alloc_base(size, align, memblock_end_of_DRAM()); 946 947 if (!ret_paddr) 948 panic("numa.c: cannot allocate %lu bytes for node %d", 949 size, nid); 950 951 ret = __va(ret_paddr); 952 953 /* 954 * We initialize the nodes in numeric order: 0, 1, 2... 955 * and hand over control from the MEMBLOCK allocator to the 956 * bootmem allocator. If this function is called for 957 * node 5, then we know that all nodes <5 are using the 958 * bootmem allocator instead of the MEMBLOCK allocator. 959 * 960 * So, check the nid from which this allocation came 961 * and double check to see if we need to use bootmem 962 * instead of the MEMBLOCK. We don't free the MEMBLOCK memory 963 * since it would be useless. 964 */ 965 new_nid = early_pfn_to_nid(ret_paddr >> PAGE_SHIFT); 966 if (new_nid < nid) { 967 ret = __alloc_bootmem_node(NODE_DATA(new_nid), 968 size, align, 0); 969 970 dbg("alloc_bootmem %p %lx\n", ret, size); 971 } 972 973 memset(ret, 0, size); 974 return ret; 975 } 976 977 static struct notifier_block ppc64_numa_nb = { 978 .notifier_call = cpu_numa_callback, 979 .priority = 1 /* Must run before sched domains notifier. */ 980 }; 981 982 static void __init mark_reserved_regions_for_nid(int nid) 983 { 984 struct pglist_data *node = NODE_DATA(nid); 985 struct memblock_region *reg; 986 987 for_each_memblock(reserved, reg) { 988 unsigned long physbase = reg->base; 989 unsigned long size = reg->size; 990 unsigned long start_pfn = physbase >> PAGE_SHIFT; 991 unsigned long end_pfn = PFN_UP(physbase + size); 992 struct node_active_region node_ar; 993 unsigned long node_end_pfn = pgdat_end_pfn(node); 994 995 /* 996 * Check to make sure that this memblock.reserved area is 997 * within the bounds of the node that we care about. 998 * Checking the nid of the start and end points is not 999 * sufficient because the reserved area could span the 1000 * entire node. 1001 */ 1002 if (end_pfn <= node->node_start_pfn || 1003 start_pfn >= node_end_pfn) 1004 continue; 1005 1006 get_node_active_region(start_pfn, &node_ar); 1007 while (start_pfn < end_pfn && 1008 node_ar.start_pfn < node_ar.end_pfn) { 1009 unsigned long reserve_size = size; 1010 /* 1011 * if reserved region extends past active region 1012 * then trim size to active region 1013 */ 1014 if (end_pfn > node_ar.end_pfn) 1015 reserve_size = (node_ar.end_pfn << PAGE_SHIFT) 1016 - physbase; 1017 /* 1018 * Only worry about *this* node, others may not 1019 * yet have valid NODE_DATA(). 1020 */ 1021 if (node_ar.nid == nid) { 1022 dbg("reserve_bootmem %lx %lx nid=%d\n", 1023 physbase, reserve_size, node_ar.nid); 1024 reserve_bootmem_node(NODE_DATA(node_ar.nid), 1025 physbase, reserve_size, 1026 BOOTMEM_DEFAULT); 1027 } 1028 /* 1029 * if reserved region is contained in the active region 1030 * then done. 1031 */ 1032 if (end_pfn <= node_ar.end_pfn) 1033 break; 1034 1035 /* 1036 * reserved region extends past the active region 1037 * get next active region that contains this 1038 * reserved region 1039 */ 1040 start_pfn = node_ar.end_pfn; 1041 physbase = start_pfn << PAGE_SHIFT; 1042 size = size - reserve_size; 1043 get_node_active_region(start_pfn, &node_ar); 1044 } 1045 } 1046 } 1047 1048 1049 void __init do_init_bootmem(void) 1050 { 1051 int nid; 1052 1053 min_low_pfn = 0; 1054 max_low_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT; 1055 max_pfn = max_low_pfn; 1056 1057 if (parse_numa_properties()) 1058 setup_nonnuma(); 1059 else 1060 dump_numa_memory_topology(); 1061 1062 for_each_online_node(nid) { 1063 unsigned long start_pfn, end_pfn; 1064 void *bootmem_vaddr; 1065 unsigned long bootmap_pages; 1066 1067 get_pfn_range_for_nid(nid, &start_pfn, &end_pfn); 1068 1069 /* 1070 * Allocate the node structure node local if possible 1071 * 1072 * Be careful moving this around, as it relies on all 1073 * previous nodes' bootmem to be initialized and have 1074 * all reserved areas marked. 1075 */ 1076 NODE_DATA(nid) = careful_zallocation(nid, 1077 sizeof(struct pglist_data), 1078 SMP_CACHE_BYTES, end_pfn); 1079 1080 dbg("node %d\n", nid); 1081 dbg("NODE_DATA() = %p\n", NODE_DATA(nid)); 1082 1083 NODE_DATA(nid)->bdata = &bootmem_node_data[nid]; 1084 NODE_DATA(nid)->node_start_pfn = start_pfn; 1085 NODE_DATA(nid)->node_spanned_pages = end_pfn - start_pfn; 1086 1087 if (NODE_DATA(nid)->node_spanned_pages == 0) 1088 continue; 1089 1090 dbg("start_paddr = %lx\n", start_pfn << PAGE_SHIFT); 1091 dbg("end_paddr = %lx\n", end_pfn << PAGE_SHIFT); 1092 1093 bootmap_pages = bootmem_bootmap_pages(end_pfn - start_pfn); 1094 bootmem_vaddr = careful_zallocation(nid, 1095 bootmap_pages << PAGE_SHIFT, 1096 PAGE_SIZE, end_pfn); 1097 1098 dbg("bootmap_vaddr = %p\n", bootmem_vaddr); 1099 1100 init_bootmem_node(NODE_DATA(nid), 1101 __pa(bootmem_vaddr) >> PAGE_SHIFT, 1102 start_pfn, end_pfn); 1103 1104 free_bootmem_with_active_regions(nid, end_pfn); 1105 /* 1106 * Be very careful about moving this around. Future 1107 * calls to careful_zallocation() depend on this getting 1108 * done correctly. 1109 */ 1110 mark_reserved_regions_for_nid(nid); 1111 sparse_memory_present_with_active_regions(nid); 1112 } 1113 1114 init_bootmem_done = 1; 1115 1116 /* 1117 * Now bootmem is initialised we can create the node to cpumask 1118 * lookup tables and setup the cpu callback to populate them. 1119 */ 1120 setup_node_to_cpumask_map(); 1121 1122 reset_numa_cpu_lookup_table(); 1123 register_cpu_notifier(&ppc64_numa_nb); 1124 cpu_numa_callback(&ppc64_numa_nb, CPU_UP_PREPARE, 1125 (void *)(unsigned long)boot_cpuid); 1126 } 1127 1128 void __init paging_init(void) 1129 { 1130 unsigned long max_zone_pfns[MAX_NR_ZONES]; 1131 memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); 1132 max_zone_pfns[ZONE_DMA] = memblock_end_of_DRAM() >> PAGE_SHIFT; 1133 free_area_init_nodes(max_zone_pfns); 1134 } 1135 1136 static int __init early_numa(char *p) 1137 { 1138 if (!p) 1139 return 0; 1140 1141 if (strstr(p, "off")) 1142 numa_enabled = 0; 1143 1144 if (strstr(p, "debug")) 1145 numa_debug = 1; 1146 1147 p = strstr(p, "fake="); 1148 if (p) 1149 cmdline = p + strlen("fake="); 1150 1151 return 0; 1152 } 1153 early_param("numa", early_numa); 1154 1155 #ifdef CONFIG_MEMORY_HOTPLUG 1156 /* 1157 * Find the node associated with a hot added memory section for 1158 * memory represented in the device tree by the property 1159 * ibm,dynamic-reconfiguration-memory/ibm,dynamic-memory. 1160 */ 1161 static int hot_add_drconf_scn_to_nid(struct device_node *memory, 1162 unsigned long scn_addr) 1163 { 1164 const __be32 *dm; 1165 unsigned int drconf_cell_cnt, rc; 1166 unsigned long lmb_size; 1167 struct assoc_arrays aa; 1168 int nid = -1; 1169 1170 drconf_cell_cnt = of_get_drconf_memory(memory, &dm); 1171 if (!drconf_cell_cnt) 1172 return -1; 1173 1174 lmb_size = of_get_lmb_size(memory); 1175 if (!lmb_size) 1176 return -1; 1177 1178 rc = of_get_assoc_arrays(memory, &aa); 1179 if (rc) 1180 return -1; 1181 1182 for (; drconf_cell_cnt != 0; --drconf_cell_cnt) { 1183 struct of_drconf_cell drmem; 1184 1185 read_drconf_cell(&drmem, &dm); 1186 1187 /* skip this block if it is reserved or not assigned to 1188 * this partition */ 1189 if ((drmem.flags & DRCONF_MEM_RESERVED) 1190 || !(drmem.flags & DRCONF_MEM_ASSIGNED)) 1191 continue; 1192 1193 if ((scn_addr < drmem.base_addr) 1194 || (scn_addr >= (drmem.base_addr + lmb_size))) 1195 continue; 1196 1197 nid = of_drconf_to_nid_single(&drmem, &aa); 1198 break; 1199 } 1200 1201 return nid; 1202 } 1203 1204 /* 1205 * Find the node associated with a hot added memory section for memory 1206 * represented in the device tree as a node (i.e. memory@XXXX) for 1207 * each memblock. 1208 */ 1209 static int hot_add_node_scn_to_nid(unsigned long scn_addr) 1210 { 1211 struct device_node *memory; 1212 int nid = -1; 1213 1214 for_each_node_by_type(memory, "memory") { 1215 unsigned long start, size; 1216 int ranges; 1217 const __be32 *memcell_buf; 1218 unsigned int len; 1219 1220 memcell_buf = of_get_property(memory, "reg", &len); 1221 if (!memcell_buf || len <= 0) 1222 continue; 1223 1224 /* ranges in cell */ 1225 ranges = (len >> 2) / (n_mem_addr_cells + n_mem_size_cells); 1226 1227 while (ranges--) { 1228 start = read_n_cells(n_mem_addr_cells, &memcell_buf); 1229 size = read_n_cells(n_mem_size_cells, &memcell_buf); 1230 1231 if ((scn_addr < start) || (scn_addr >= (start + size))) 1232 continue; 1233 1234 nid = of_node_to_nid_single(memory); 1235 break; 1236 } 1237 1238 if (nid >= 0) 1239 break; 1240 } 1241 1242 of_node_put(memory); 1243 1244 return nid; 1245 } 1246 1247 /* 1248 * Find the node associated with a hot added memory section. Section 1249 * corresponds to a SPARSEMEM section, not an MEMBLOCK. It is assumed that 1250 * sections are fully contained within a single MEMBLOCK. 1251 */ 1252 int hot_add_scn_to_nid(unsigned long scn_addr) 1253 { 1254 struct device_node *memory = NULL; 1255 int nid, found = 0; 1256 1257 if (!numa_enabled || (min_common_depth < 0)) 1258 return first_online_node; 1259 1260 memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory"); 1261 if (memory) { 1262 nid = hot_add_drconf_scn_to_nid(memory, scn_addr); 1263 of_node_put(memory); 1264 } else { 1265 nid = hot_add_node_scn_to_nid(scn_addr); 1266 } 1267 1268 if (nid < 0 || !node_online(nid)) 1269 nid = first_online_node; 1270 1271 if (NODE_DATA(nid)->node_spanned_pages) 1272 return nid; 1273 1274 for_each_online_node(nid) { 1275 if (NODE_DATA(nid)->node_spanned_pages) { 1276 found = 1; 1277 break; 1278 } 1279 } 1280 1281 BUG_ON(!found); 1282 return nid; 1283 } 1284 1285 static u64 hot_add_drconf_memory_max(void) 1286 { 1287 struct device_node *memory = NULL; 1288 unsigned int drconf_cell_cnt = 0; 1289 u64 lmb_size = 0; 1290 const __be32 *dm = NULL; 1291 1292 memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory"); 1293 if (memory) { 1294 drconf_cell_cnt = of_get_drconf_memory(memory, &dm); 1295 lmb_size = of_get_lmb_size(memory); 1296 of_node_put(memory); 1297 } 1298 return lmb_size * drconf_cell_cnt; 1299 } 1300 1301 /* 1302 * memory_hotplug_max - return max address of memory that may be added 1303 * 1304 * This is currently only used on systems that support drconfig memory 1305 * hotplug. 1306 */ 1307 u64 memory_hotplug_max(void) 1308 { 1309 return max(hot_add_drconf_memory_max(), memblock_end_of_DRAM()); 1310 } 1311 #endif /* CONFIG_MEMORY_HOTPLUG */ 1312 1313 /* Virtual Processor Home Node (VPHN) support */ 1314 #ifdef CONFIG_PPC_SPLPAR 1315 struct topology_update_data { 1316 struct topology_update_data *next; 1317 unsigned int cpu; 1318 int old_nid; 1319 int new_nid; 1320 }; 1321 1322 static u8 vphn_cpu_change_counts[NR_CPUS][MAX_DISTANCE_REF_POINTS]; 1323 static cpumask_t cpu_associativity_changes_mask; 1324 static int vphn_enabled; 1325 static int prrn_enabled; 1326 static void reset_topology_timer(void); 1327 1328 /* 1329 * Store the current values of the associativity change counters in the 1330 * hypervisor. 1331 */ 1332 static void setup_cpu_associativity_change_counters(void) 1333 { 1334 int cpu; 1335 1336 /* The VPHN feature supports a maximum of 8 reference points */ 1337 BUILD_BUG_ON(MAX_DISTANCE_REF_POINTS > 8); 1338 1339 for_each_possible_cpu(cpu) { 1340 int i; 1341 u8 *counts = vphn_cpu_change_counts[cpu]; 1342 volatile u8 *hypervisor_counts = lppaca[cpu].vphn_assoc_counts; 1343 1344 for (i = 0; i < distance_ref_points_depth; i++) 1345 counts[i] = hypervisor_counts[i]; 1346 } 1347 } 1348 1349 /* 1350 * The hypervisor maintains a set of 8 associativity change counters in 1351 * the VPA of each cpu that correspond to the associativity levels in the 1352 * ibm,associativity-reference-points property. When an associativity 1353 * level changes, the corresponding counter is incremented. 1354 * 1355 * Set a bit in cpu_associativity_changes_mask for each cpu whose home 1356 * node associativity levels have changed. 1357 * 1358 * Returns the number of cpus with unhandled associativity changes. 1359 */ 1360 static int update_cpu_associativity_changes_mask(void) 1361 { 1362 int cpu; 1363 cpumask_t *changes = &cpu_associativity_changes_mask; 1364 1365 for_each_possible_cpu(cpu) { 1366 int i, changed = 0; 1367 u8 *counts = vphn_cpu_change_counts[cpu]; 1368 volatile u8 *hypervisor_counts = lppaca[cpu].vphn_assoc_counts; 1369 1370 for (i = 0; i < distance_ref_points_depth; i++) { 1371 if (hypervisor_counts[i] != counts[i]) { 1372 counts[i] = hypervisor_counts[i]; 1373 changed = 1; 1374 } 1375 } 1376 if (changed) { 1377 cpumask_or(changes, changes, cpu_sibling_mask(cpu)); 1378 cpu = cpu_last_thread_sibling(cpu); 1379 } 1380 } 1381 1382 return cpumask_weight(changes); 1383 } 1384 1385 /* 1386 * 6 64-bit registers unpacked into 12 32-bit associativity values. To form 1387 * the complete property we have to add the length in the first cell. 1388 */ 1389 #define VPHN_ASSOC_BUFSIZE (6*sizeof(u64)/sizeof(u32) + 1) 1390 1391 /* 1392 * Convert the associativity domain numbers returned from the hypervisor 1393 * to the sequence they would appear in the ibm,associativity property. 1394 */ 1395 static int vphn_unpack_associativity(const long *packed, __be32 *unpacked) 1396 { 1397 int i, nr_assoc_doms = 0; 1398 const __be16 *field = (const __be16 *) packed; 1399 1400 #define VPHN_FIELD_UNUSED (0xffff) 1401 #define VPHN_FIELD_MSB (0x8000) 1402 #define VPHN_FIELD_MASK (~VPHN_FIELD_MSB) 1403 1404 for (i = 1; i < VPHN_ASSOC_BUFSIZE; i++) { 1405 if (be16_to_cpup(field) == VPHN_FIELD_UNUSED) { 1406 /* All significant fields processed, and remaining 1407 * fields contain the reserved value of all 1's. 1408 * Just store them. 1409 */ 1410 unpacked[i] = *((__be32 *)field); 1411 field += 2; 1412 } else if (be16_to_cpup(field) & VPHN_FIELD_MSB) { 1413 /* Data is in the lower 15 bits of this field */ 1414 unpacked[i] = cpu_to_be32( 1415 be16_to_cpup(field) & VPHN_FIELD_MASK); 1416 field++; 1417 nr_assoc_doms++; 1418 } else { 1419 /* Data is in the lower 15 bits of this field 1420 * concatenated with the next 16 bit field 1421 */ 1422 unpacked[i] = *((__be32 *)field); 1423 field += 2; 1424 nr_assoc_doms++; 1425 } 1426 } 1427 1428 /* The first cell contains the length of the property */ 1429 unpacked[0] = cpu_to_be32(nr_assoc_doms); 1430 1431 return nr_assoc_doms; 1432 } 1433 1434 /* 1435 * Retrieve the new associativity information for a virtual processor's 1436 * home node. 1437 */ 1438 static long hcall_vphn(unsigned long cpu, __be32 *associativity) 1439 { 1440 long rc; 1441 long retbuf[PLPAR_HCALL9_BUFSIZE] = {0}; 1442 u64 flags = 1; 1443 int hwcpu = get_hard_smp_processor_id(cpu); 1444 1445 rc = plpar_hcall9(H_HOME_NODE_ASSOCIATIVITY, retbuf, flags, hwcpu); 1446 vphn_unpack_associativity(retbuf, associativity); 1447 1448 return rc; 1449 } 1450 1451 static long vphn_get_associativity(unsigned long cpu, 1452 __be32 *associativity) 1453 { 1454 long rc; 1455 1456 rc = hcall_vphn(cpu, associativity); 1457 1458 switch (rc) { 1459 case H_FUNCTION: 1460 printk(KERN_INFO 1461 "VPHN is not supported. Disabling polling...\n"); 1462 stop_topology_update(); 1463 break; 1464 case H_HARDWARE: 1465 printk(KERN_ERR 1466 "hcall_vphn() experienced a hardware fault " 1467 "preventing VPHN. Disabling polling...\n"); 1468 stop_topology_update(); 1469 } 1470 1471 return rc; 1472 } 1473 1474 /* 1475 * Update the CPU maps and sysfs entries for a single CPU when its NUMA 1476 * characteristics change. This function doesn't perform any locking and is 1477 * only safe to call from stop_machine(). 1478 */ 1479 static int update_cpu_topology(void *data) 1480 { 1481 struct topology_update_data *update; 1482 unsigned long cpu; 1483 1484 if (!data) 1485 return -EINVAL; 1486 1487 cpu = smp_processor_id(); 1488 1489 for (update = data; update; update = update->next) { 1490 if (cpu != update->cpu) 1491 continue; 1492 1493 unmap_cpu_from_node(update->cpu); 1494 map_cpu_to_node(update->cpu, update->new_nid); 1495 vdso_getcpu_init(); 1496 } 1497 1498 return 0; 1499 } 1500 1501 static int update_lookup_table(void *data) 1502 { 1503 struct topology_update_data *update; 1504 1505 if (!data) 1506 return -EINVAL; 1507 1508 /* 1509 * Upon topology update, the numa-cpu lookup table needs to be updated 1510 * for all threads in the core, including offline CPUs, to ensure that 1511 * future hotplug operations respect the cpu-to-node associativity 1512 * properly. 1513 */ 1514 for (update = data; update; update = update->next) { 1515 int nid, base, j; 1516 1517 nid = update->new_nid; 1518 base = cpu_first_thread_sibling(update->cpu); 1519 1520 for (j = 0; j < threads_per_core; j++) { 1521 update_numa_cpu_lookup_table(base + j, nid); 1522 } 1523 } 1524 1525 return 0; 1526 } 1527 1528 /* 1529 * Update the node maps and sysfs entries for each cpu whose home node 1530 * has changed. Returns 1 when the topology has changed, and 0 otherwise. 1531 */ 1532 int arch_update_cpu_topology(void) 1533 { 1534 unsigned int cpu, sibling, changed = 0; 1535 struct topology_update_data *updates, *ud; 1536 __be32 associativity[VPHN_ASSOC_BUFSIZE] = {0}; 1537 cpumask_t updated_cpus; 1538 struct device *dev; 1539 int weight, new_nid, i = 0; 1540 1541 weight = cpumask_weight(&cpu_associativity_changes_mask); 1542 if (!weight) 1543 return 0; 1544 1545 updates = kzalloc(weight * (sizeof(*updates)), GFP_KERNEL); 1546 if (!updates) 1547 return 0; 1548 1549 cpumask_clear(&updated_cpus); 1550 1551 for_each_cpu(cpu, &cpu_associativity_changes_mask) { 1552 /* 1553 * If siblings aren't flagged for changes, updates list 1554 * will be too short. Skip on this update and set for next 1555 * update. 1556 */ 1557 if (!cpumask_subset(cpu_sibling_mask(cpu), 1558 &cpu_associativity_changes_mask)) { 1559 pr_info("Sibling bits not set for associativity " 1560 "change, cpu%d\n", cpu); 1561 cpumask_or(&cpu_associativity_changes_mask, 1562 &cpu_associativity_changes_mask, 1563 cpu_sibling_mask(cpu)); 1564 cpu = cpu_last_thread_sibling(cpu); 1565 continue; 1566 } 1567 1568 /* Use associativity from first thread for all siblings */ 1569 vphn_get_associativity(cpu, associativity); 1570 new_nid = associativity_to_nid(associativity); 1571 if (new_nid < 0 || !node_online(new_nid)) 1572 new_nid = first_online_node; 1573 1574 if (new_nid == numa_cpu_lookup_table[cpu]) { 1575 cpumask_andnot(&cpu_associativity_changes_mask, 1576 &cpu_associativity_changes_mask, 1577 cpu_sibling_mask(cpu)); 1578 cpu = cpu_last_thread_sibling(cpu); 1579 continue; 1580 } 1581 1582 for_each_cpu(sibling, cpu_sibling_mask(cpu)) { 1583 ud = &updates[i++]; 1584 ud->cpu = sibling; 1585 ud->new_nid = new_nid; 1586 ud->old_nid = numa_cpu_lookup_table[sibling]; 1587 cpumask_set_cpu(sibling, &updated_cpus); 1588 if (i < weight) 1589 ud->next = &updates[i]; 1590 } 1591 cpu = cpu_last_thread_sibling(cpu); 1592 } 1593 1594 /* 1595 * In cases where we have nothing to update (because the updates list 1596 * is too short or because the new topology is same as the old one), 1597 * skip invoking update_cpu_topology() via stop-machine(). This is 1598 * necessary (and not just a fast-path optimization) since stop-machine 1599 * can end up electing a random CPU to run update_cpu_topology(), and 1600 * thus trick us into setting up incorrect cpu-node mappings (since 1601 * 'updates' is kzalloc()'ed). 1602 * 1603 * And for the similar reason, we will skip all the following updating. 1604 */ 1605 if (!cpumask_weight(&updated_cpus)) 1606 goto out; 1607 1608 stop_machine(update_cpu_topology, &updates[0], &updated_cpus); 1609 1610 /* 1611 * Update the numa-cpu lookup table with the new mappings, even for 1612 * offline CPUs. It is best to perform this update from the stop- 1613 * machine context. 1614 */ 1615 stop_machine(update_lookup_table, &updates[0], 1616 cpumask_of(raw_smp_processor_id())); 1617 1618 for (ud = &updates[0]; ud; ud = ud->next) { 1619 unregister_cpu_under_node(ud->cpu, ud->old_nid); 1620 register_cpu_under_node(ud->cpu, ud->new_nid); 1621 1622 dev = get_cpu_device(ud->cpu); 1623 if (dev) 1624 kobject_uevent(&dev->kobj, KOBJ_CHANGE); 1625 cpumask_clear_cpu(ud->cpu, &cpu_associativity_changes_mask); 1626 changed = 1; 1627 } 1628 1629 out: 1630 kfree(updates); 1631 return changed; 1632 } 1633 1634 static void topology_work_fn(struct work_struct *work) 1635 { 1636 rebuild_sched_domains(); 1637 } 1638 static DECLARE_WORK(topology_work, topology_work_fn); 1639 1640 static void topology_schedule_update(void) 1641 { 1642 schedule_work(&topology_work); 1643 } 1644 1645 static void topology_timer_fn(unsigned long ignored) 1646 { 1647 if (prrn_enabled && cpumask_weight(&cpu_associativity_changes_mask)) 1648 topology_schedule_update(); 1649 else if (vphn_enabled) { 1650 if (update_cpu_associativity_changes_mask() > 0) 1651 topology_schedule_update(); 1652 reset_topology_timer(); 1653 } 1654 } 1655 static struct timer_list topology_timer = 1656 TIMER_INITIALIZER(topology_timer_fn, 0, 0); 1657 1658 static void reset_topology_timer(void) 1659 { 1660 topology_timer.data = 0; 1661 topology_timer.expires = jiffies + 60 * HZ; 1662 mod_timer(&topology_timer, topology_timer.expires); 1663 } 1664 1665 #ifdef CONFIG_SMP 1666 1667 static void stage_topology_update(int core_id) 1668 { 1669 cpumask_or(&cpu_associativity_changes_mask, 1670 &cpu_associativity_changes_mask, cpu_sibling_mask(core_id)); 1671 reset_topology_timer(); 1672 } 1673 1674 static int dt_update_callback(struct notifier_block *nb, 1675 unsigned long action, void *data) 1676 { 1677 struct of_prop_reconfig *update; 1678 int rc = NOTIFY_DONE; 1679 1680 switch (action) { 1681 case OF_RECONFIG_UPDATE_PROPERTY: 1682 update = (struct of_prop_reconfig *)data; 1683 if (!of_prop_cmp(update->dn->type, "cpu") && 1684 !of_prop_cmp(update->prop->name, "ibm,associativity")) { 1685 u32 core_id; 1686 of_property_read_u32(update->dn, "reg", &core_id); 1687 stage_topology_update(core_id); 1688 rc = NOTIFY_OK; 1689 } 1690 break; 1691 } 1692 1693 return rc; 1694 } 1695 1696 static struct notifier_block dt_update_nb = { 1697 .notifier_call = dt_update_callback, 1698 }; 1699 1700 #endif 1701 1702 /* 1703 * Start polling for associativity changes. 1704 */ 1705 int start_topology_update(void) 1706 { 1707 int rc = 0; 1708 1709 if (firmware_has_feature(FW_FEATURE_PRRN)) { 1710 if (!prrn_enabled) { 1711 prrn_enabled = 1; 1712 vphn_enabled = 0; 1713 #ifdef CONFIG_SMP 1714 rc = of_reconfig_notifier_register(&dt_update_nb); 1715 #endif 1716 } 1717 } else if (firmware_has_feature(FW_FEATURE_VPHN) && 1718 lppaca_shared_proc(get_lppaca())) { 1719 if (!vphn_enabled) { 1720 prrn_enabled = 0; 1721 vphn_enabled = 1; 1722 setup_cpu_associativity_change_counters(); 1723 init_timer_deferrable(&topology_timer); 1724 reset_topology_timer(); 1725 } 1726 } 1727 1728 return rc; 1729 } 1730 1731 /* 1732 * Disable polling for VPHN associativity changes. 1733 */ 1734 int stop_topology_update(void) 1735 { 1736 int rc = 0; 1737 1738 if (prrn_enabled) { 1739 prrn_enabled = 0; 1740 #ifdef CONFIG_SMP 1741 rc = of_reconfig_notifier_unregister(&dt_update_nb); 1742 #endif 1743 } else if (vphn_enabled) { 1744 vphn_enabled = 0; 1745 rc = del_timer_sync(&topology_timer); 1746 } 1747 1748 return rc; 1749 } 1750 1751 int prrn_is_enabled(void) 1752 { 1753 return prrn_enabled; 1754 } 1755 1756 static int topology_read(struct seq_file *file, void *v) 1757 { 1758 if (vphn_enabled || prrn_enabled) 1759 seq_puts(file, "on\n"); 1760 else 1761 seq_puts(file, "off\n"); 1762 1763 return 0; 1764 } 1765 1766 static int topology_open(struct inode *inode, struct file *file) 1767 { 1768 return single_open(file, topology_read, NULL); 1769 } 1770 1771 static ssize_t topology_write(struct file *file, const char __user *buf, 1772 size_t count, loff_t *off) 1773 { 1774 char kbuf[4]; /* "on" or "off" plus null. */ 1775 int read_len; 1776 1777 read_len = count < 3 ? count : 3; 1778 if (copy_from_user(kbuf, buf, read_len)) 1779 return -EINVAL; 1780 1781 kbuf[read_len] = '\0'; 1782 1783 if (!strncmp(kbuf, "on", 2)) 1784 start_topology_update(); 1785 else if (!strncmp(kbuf, "off", 3)) 1786 stop_topology_update(); 1787 else 1788 return -EINVAL; 1789 1790 return count; 1791 } 1792 1793 static const struct file_operations topology_ops = { 1794 .read = seq_read, 1795 .write = topology_write, 1796 .open = topology_open, 1797 .release = single_release 1798 }; 1799 1800 static int topology_update_init(void) 1801 { 1802 start_topology_update(); 1803 proc_create("powerpc/topology_updates", 0644, NULL, &topology_ops); 1804 1805 return 0; 1806 } 1807 device_initcall(topology_update_init); 1808 #endif /* CONFIG_PPC_SPLPAR */ 1809