1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright IBM Corp. 2007, 2011 4 */ 5 6 #define KMSG_COMPONENT "cpu" 7 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt 8 9 #include <linux/workqueue.h> 10 #include <linux/memblock.h> 11 #include <linux/uaccess.h> 12 #include <linux/sysctl.h> 13 #include <linux/cpuset.h> 14 #include <linux/device.h> 15 #include <linux/export.h> 16 #include <linux/kernel.h> 17 #include <linux/sched.h> 18 #include <linux/sched/topology.h> 19 #include <linux/delay.h> 20 #include <linux/init.h> 21 #include <linux/slab.h> 22 #include <linux/cpu.h> 23 #include <linux/smp.h> 24 #include <linux/mm.h> 25 #include <linux/nodemask.h> 26 #include <linux/node.h> 27 #include <asm/sysinfo.h> 28 29 #define PTF_HORIZONTAL (0UL) 30 #define PTF_VERTICAL (1UL) 31 #define PTF_CHECK (2UL) 32 33 enum { 34 TOPOLOGY_MODE_HW, 35 TOPOLOGY_MODE_SINGLE, 36 TOPOLOGY_MODE_PACKAGE, 37 TOPOLOGY_MODE_UNINITIALIZED 38 }; 39 40 struct mask_info { 41 struct mask_info *next; 42 unsigned char id; 43 cpumask_t mask; 44 }; 45 46 static int topology_mode = TOPOLOGY_MODE_UNINITIALIZED; 47 static void set_topology_timer(void); 48 static void topology_work_fn(struct work_struct *work); 49 static struct sysinfo_15_1_x *tl_info; 50 51 static DECLARE_WORK(topology_work, topology_work_fn); 52 53 /* 54 * Socket/Book linked lists and cpu_topology updates are 55 * protected by "sched_domains_mutex". 56 */ 57 static struct mask_info socket_info; 58 static struct mask_info book_info; 59 static struct mask_info drawer_info; 60 61 struct cpu_topology_s390 cpu_topology[NR_CPUS]; 62 EXPORT_SYMBOL_GPL(cpu_topology); 63 64 static void cpu_group_map(cpumask_t *dst, struct mask_info *info, unsigned int cpu) 65 { 66 static cpumask_t mask; 67 68 cpumask_clear(&mask); 69 if (!cpumask_test_cpu(cpu, &cpu_setup_mask)) 70 goto out; 71 cpumask_set_cpu(cpu, &mask); 72 switch (topology_mode) { 73 case TOPOLOGY_MODE_HW: 74 while (info) { 75 if (cpumask_test_cpu(cpu, &info->mask)) { 76 cpumask_copy(&mask, &info->mask); 77 break; 78 } 79 info = info->next; 80 } 81 break; 82 case TOPOLOGY_MODE_PACKAGE: 83 cpumask_copy(&mask, cpu_present_mask); 84 break; 85 default: 86 fallthrough; 87 case TOPOLOGY_MODE_SINGLE: 88 break; 89 } 90 cpumask_and(&mask, &mask, &cpu_setup_mask); 91 out: 92 cpumask_copy(dst, &mask); 93 } 94 95 static void cpu_thread_map(cpumask_t *dst, unsigned int cpu) 96 { 97 static cpumask_t mask; 98 int i; 99 100 cpumask_clear(&mask); 101 if (!cpumask_test_cpu(cpu, &cpu_setup_mask)) 102 goto out; 103 cpumask_set_cpu(cpu, &mask); 104 if (topology_mode != TOPOLOGY_MODE_HW) 105 goto out; 106 cpu -= cpu % (smp_cpu_mtid + 1); 107 for (i = 0; i <= smp_cpu_mtid; i++) { 108 if (cpumask_test_cpu(cpu + i, &cpu_setup_mask)) 109 cpumask_set_cpu(cpu + i, &mask); 110 } 111 out: 112 cpumask_copy(dst, &mask); 113 } 114 115 #define TOPOLOGY_CORE_BITS 64 116 117 static void add_cpus_to_mask(struct topology_core *tl_core, 118 struct mask_info *drawer, 119 struct mask_info *book, 120 struct mask_info *socket) 121 { 122 struct cpu_topology_s390 *topo; 123 unsigned int core; 124 125 for_each_set_bit(core, &tl_core->mask, TOPOLOGY_CORE_BITS) { 126 unsigned int rcore; 127 int lcpu, i; 128 129 rcore = TOPOLOGY_CORE_BITS - 1 - core + tl_core->origin; 130 lcpu = smp_find_processor_id(rcore << smp_cpu_mt_shift); 131 if (lcpu < 0) 132 continue; 133 for (i = 0; i <= smp_cpu_mtid; i++) { 134 topo = &cpu_topology[lcpu + i]; 135 topo->drawer_id = drawer->id; 136 topo->book_id = book->id; 137 topo->socket_id = socket->id; 138 topo->core_id = rcore; 139 topo->thread_id = lcpu + i; 140 topo->dedicated = tl_core->d; 141 cpumask_set_cpu(lcpu + i, &drawer->mask); 142 cpumask_set_cpu(lcpu + i, &book->mask); 143 cpumask_set_cpu(lcpu + i, &socket->mask); 144 smp_cpu_set_polarization(lcpu + i, tl_core->pp); 145 } 146 } 147 } 148 149 static void clear_masks(void) 150 { 151 struct mask_info *info; 152 153 info = &socket_info; 154 while (info) { 155 cpumask_clear(&info->mask); 156 info = info->next; 157 } 158 info = &book_info; 159 while (info) { 160 cpumask_clear(&info->mask); 161 info = info->next; 162 } 163 info = &drawer_info; 164 while (info) { 165 cpumask_clear(&info->mask); 166 info = info->next; 167 } 168 } 169 170 static union topology_entry *next_tle(union topology_entry *tle) 171 { 172 if (!tle->nl) 173 return (union topology_entry *)((struct topology_core *)tle + 1); 174 return (union topology_entry *)((struct topology_container *)tle + 1); 175 } 176 177 static void tl_to_masks(struct sysinfo_15_1_x *info) 178 { 179 struct mask_info *socket = &socket_info; 180 struct mask_info *book = &book_info; 181 struct mask_info *drawer = &drawer_info; 182 union topology_entry *tle, *end; 183 184 clear_masks(); 185 tle = info->tle; 186 end = (union topology_entry *)((unsigned long)info + info->length); 187 while (tle < end) { 188 switch (tle->nl) { 189 case 3: 190 drawer = drawer->next; 191 drawer->id = tle->container.id; 192 break; 193 case 2: 194 book = book->next; 195 book->id = tle->container.id; 196 break; 197 case 1: 198 socket = socket->next; 199 socket->id = tle->container.id; 200 break; 201 case 0: 202 add_cpus_to_mask(&tle->cpu, drawer, book, socket); 203 break; 204 default: 205 clear_masks(); 206 return; 207 } 208 tle = next_tle(tle); 209 } 210 } 211 212 static void topology_update_polarization_simple(void) 213 { 214 int cpu; 215 216 for_each_possible_cpu(cpu) 217 smp_cpu_set_polarization(cpu, POLARIZATION_HRZ); 218 } 219 220 static int ptf(unsigned long fc) 221 { 222 int rc; 223 224 asm volatile( 225 " .insn rre,0xb9a20000,%1,%1\n" 226 " ipm %0\n" 227 " srl %0,28\n" 228 : "=d" (rc) 229 : "d" (fc) : "cc"); 230 return rc; 231 } 232 233 int topology_set_cpu_management(int fc) 234 { 235 int cpu, rc; 236 237 if (!MACHINE_HAS_TOPOLOGY) 238 return -EOPNOTSUPP; 239 if (fc) 240 rc = ptf(PTF_VERTICAL); 241 else 242 rc = ptf(PTF_HORIZONTAL); 243 if (rc) 244 return -EBUSY; 245 for_each_possible_cpu(cpu) 246 smp_cpu_set_polarization(cpu, POLARIZATION_UNKNOWN); 247 return rc; 248 } 249 250 void update_cpu_masks(void) 251 { 252 struct cpu_topology_s390 *topo, *topo_package, *topo_sibling; 253 int cpu, sibling, pkg_first, smt_first, id; 254 255 for_each_possible_cpu(cpu) { 256 topo = &cpu_topology[cpu]; 257 cpu_thread_map(&topo->thread_mask, cpu); 258 cpu_group_map(&topo->core_mask, &socket_info, cpu); 259 cpu_group_map(&topo->book_mask, &book_info, cpu); 260 cpu_group_map(&topo->drawer_mask, &drawer_info, cpu); 261 topo->booted_cores = 0; 262 if (topology_mode != TOPOLOGY_MODE_HW) { 263 id = topology_mode == TOPOLOGY_MODE_PACKAGE ? 0 : cpu; 264 topo->thread_id = cpu; 265 topo->core_id = cpu; 266 topo->socket_id = id; 267 topo->book_id = id; 268 topo->drawer_id = id; 269 } 270 } 271 for_each_online_cpu(cpu) { 272 topo = &cpu_topology[cpu]; 273 pkg_first = cpumask_first(&topo->core_mask); 274 topo_package = &cpu_topology[pkg_first]; 275 if (cpu == pkg_first) { 276 for_each_cpu(sibling, &topo->core_mask) { 277 topo_sibling = &cpu_topology[sibling]; 278 smt_first = cpumask_first(&topo_sibling->thread_mask); 279 if (sibling == smt_first) 280 topo_package->booted_cores++; 281 } 282 } else { 283 topo->booted_cores = topo_package->booted_cores; 284 } 285 } 286 } 287 288 void store_topology(struct sysinfo_15_1_x *info) 289 { 290 stsi(info, 15, 1, topology_mnest_limit()); 291 } 292 293 static void __arch_update_dedicated_flag(void *arg) 294 { 295 if (topology_cpu_dedicated(smp_processor_id())) 296 set_cpu_flag(CIF_DEDICATED_CPU); 297 else 298 clear_cpu_flag(CIF_DEDICATED_CPU); 299 } 300 301 static int __arch_update_cpu_topology(void) 302 { 303 struct sysinfo_15_1_x *info = tl_info; 304 int rc = 0; 305 306 mutex_lock(&smp_cpu_state_mutex); 307 if (MACHINE_HAS_TOPOLOGY) { 308 rc = 1; 309 store_topology(info); 310 tl_to_masks(info); 311 } 312 update_cpu_masks(); 313 if (!MACHINE_HAS_TOPOLOGY) 314 topology_update_polarization_simple(); 315 mutex_unlock(&smp_cpu_state_mutex); 316 return rc; 317 } 318 319 int arch_update_cpu_topology(void) 320 { 321 struct device *dev; 322 int cpu, rc; 323 324 rc = __arch_update_cpu_topology(); 325 on_each_cpu(__arch_update_dedicated_flag, NULL, 0); 326 for_each_online_cpu(cpu) { 327 dev = get_cpu_device(cpu); 328 if (dev) 329 kobject_uevent(&dev->kobj, KOBJ_CHANGE); 330 } 331 return rc; 332 } 333 334 static void topology_work_fn(struct work_struct *work) 335 { 336 rebuild_sched_domains(); 337 } 338 339 void topology_schedule_update(void) 340 { 341 schedule_work(&topology_work); 342 } 343 344 static void topology_flush_work(void) 345 { 346 flush_work(&topology_work); 347 } 348 349 static void topology_timer_fn(struct timer_list *unused) 350 { 351 if (ptf(PTF_CHECK)) 352 topology_schedule_update(); 353 set_topology_timer(); 354 } 355 356 static struct timer_list topology_timer; 357 358 static atomic_t topology_poll = ATOMIC_INIT(0); 359 360 static void set_topology_timer(void) 361 { 362 if (atomic_add_unless(&topology_poll, -1, 0)) 363 mod_timer(&topology_timer, jiffies + msecs_to_jiffies(100)); 364 else 365 mod_timer(&topology_timer, jiffies + msecs_to_jiffies(60 * MSEC_PER_SEC)); 366 } 367 368 void topology_expect_change(void) 369 { 370 if (!MACHINE_HAS_TOPOLOGY) 371 return; 372 /* This is racy, but it doesn't matter since it is just a heuristic. 373 * Worst case is that we poll in a higher frequency for a bit longer. 374 */ 375 if (atomic_read(&topology_poll) > 60) 376 return; 377 atomic_add(60, &topology_poll); 378 set_topology_timer(); 379 } 380 381 static int cpu_management; 382 383 static ssize_t dispatching_show(struct device *dev, 384 struct device_attribute *attr, 385 char *buf) 386 { 387 ssize_t count; 388 389 mutex_lock(&smp_cpu_state_mutex); 390 count = sprintf(buf, "%d\n", cpu_management); 391 mutex_unlock(&smp_cpu_state_mutex); 392 return count; 393 } 394 395 static ssize_t dispatching_store(struct device *dev, 396 struct device_attribute *attr, 397 const char *buf, 398 size_t count) 399 { 400 int val, rc; 401 char delim; 402 403 if (sscanf(buf, "%d %c", &val, &delim) != 1) 404 return -EINVAL; 405 if (val != 0 && val != 1) 406 return -EINVAL; 407 rc = 0; 408 cpus_read_lock(); 409 mutex_lock(&smp_cpu_state_mutex); 410 if (cpu_management == val) 411 goto out; 412 rc = topology_set_cpu_management(val); 413 if (rc) 414 goto out; 415 cpu_management = val; 416 topology_expect_change(); 417 out: 418 mutex_unlock(&smp_cpu_state_mutex); 419 cpus_read_unlock(); 420 return rc ? rc : count; 421 } 422 static DEVICE_ATTR_RW(dispatching); 423 424 static ssize_t cpu_polarization_show(struct device *dev, 425 struct device_attribute *attr, char *buf) 426 { 427 int cpu = dev->id; 428 ssize_t count; 429 430 mutex_lock(&smp_cpu_state_mutex); 431 switch (smp_cpu_get_polarization(cpu)) { 432 case POLARIZATION_HRZ: 433 count = sprintf(buf, "horizontal\n"); 434 break; 435 case POLARIZATION_VL: 436 count = sprintf(buf, "vertical:low\n"); 437 break; 438 case POLARIZATION_VM: 439 count = sprintf(buf, "vertical:medium\n"); 440 break; 441 case POLARIZATION_VH: 442 count = sprintf(buf, "vertical:high\n"); 443 break; 444 default: 445 count = sprintf(buf, "unknown\n"); 446 break; 447 } 448 mutex_unlock(&smp_cpu_state_mutex); 449 return count; 450 } 451 static DEVICE_ATTR(polarization, 0444, cpu_polarization_show, NULL); 452 453 static struct attribute *topology_cpu_attrs[] = { 454 &dev_attr_polarization.attr, 455 NULL, 456 }; 457 458 static struct attribute_group topology_cpu_attr_group = { 459 .attrs = topology_cpu_attrs, 460 }; 461 462 static ssize_t cpu_dedicated_show(struct device *dev, 463 struct device_attribute *attr, char *buf) 464 { 465 int cpu = dev->id; 466 ssize_t count; 467 468 mutex_lock(&smp_cpu_state_mutex); 469 count = sprintf(buf, "%d\n", topology_cpu_dedicated(cpu)); 470 mutex_unlock(&smp_cpu_state_mutex); 471 return count; 472 } 473 static DEVICE_ATTR(dedicated, 0444, cpu_dedicated_show, NULL); 474 475 static struct attribute *topology_extra_cpu_attrs[] = { 476 &dev_attr_dedicated.attr, 477 NULL, 478 }; 479 480 static struct attribute_group topology_extra_cpu_attr_group = { 481 .attrs = topology_extra_cpu_attrs, 482 }; 483 484 int topology_cpu_init(struct cpu *cpu) 485 { 486 int rc; 487 488 rc = sysfs_create_group(&cpu->dev.kobj, &topology_cpu_attr_group); 489 if (rc || !MACHINE_HAS_TOPOLOGY) 490 return rc; 491 rc = sysfs_create_group(&cpu->dev.kobj, &topology_extra_cpu_attr_group); 492 if (rc) 493 sysfs_remove_group(&cpu->dev.kobj, &topology_cpu_attr_group); 494 return rc; 495 } 496 497 static const struct cpumask *cpu_thread_mask(int cpu) 498 { 499 return &cpu_topology[cpu].thread_mask; 500 } 501 502 503 const struct cpumask *cpu_coregroup_mask(int cpu) 504 { 505 return &cpu_topology[cpu].core_mask; 506 } 507 508 static const struct cpumask *cpu_book_mask(int cpu) 509 { 510 return &cpu_topology[cpu].book_mask; 511 } 512 513 static const struct cpumask *cpu_drawer_mask(int cpu) 514 { 515 return &cpu_topology[cpu].drawer_mask; 516 } 517 518 static struct sched_domain_topology_level s390_topology[] = { 519 { cpu_thread_mask, cpu_smt_flags, SD_INIT_NAME(SMT) }, 520 { cpu_coregroup_mask, cpu_core_flags, SD_INIT_NAME(MC) }, 521 { cpu_book_mask, SD_INIT_NAME(BOOK) }, 522 { cpu_drawer_mask, SD_INIT_NAME(DRAWER) }, 523 { cpu_cpu_mask, SD_INIT_NAME(DIE) }, 524 { NULL, }, 525 }; 526 527 static void __init alloc_masks(struct sysinfo_15_1_x *info, 528 struct mask_info *mask, int offset) 529 { 530 int i, nr_masks; 531 532 nr_masks = info->mag[TOPOLOGY_NR_MAG - offset]; 533 for (i = 0; i < info->mnest - offset; i++) 534 nr_masks *= info->mag[TOPOLOGY_NR_MAG - offset - 1 - i]; 535 nr_masks = max(nr_masks, 1); 536 for (i = 0; i < nr_masks; i++) { 537 mask->next = memblock_alloc(sizeof(*mask->next), 8); 538 if (!mask->next) 539 panic("%s: Failed to allocate %zu bytes align=0x%x\n", 540 __func__, sizeof(*mask->next), 8); 541 mask = mask->next; 542 } 543 } 544 545 void __init topology_init_early(void) 546 { 547 struct sysinfo_15_1_x *info; 548 549 set_sched_topology(s390_topology); 550 if (topology_mode == TOPOLOGY_MODE_UNINITIALIZED) { 551 if (MACHINE_HAS_TOPOLOGY) 552 topology_mode = TOPOLOGY_MODE_HW; 553 else 554 topology_mode = TOPOLOGY_MODE_SINGLE; 555 } 556 if (!MACHINE_HAS_TOPOLOGY) 557 goto out; 558 tl_info = memblock_alloc(PAGE_SIZE, PAGE_SIZE); 559 if (!tl_info) 560 panic("%s: Failed to allocate %lu bytes align=0x%lx\n", 561 __func__, PAGE_SIZE, PAGE_SIZE); 562 info = tl_info; 563 store_topology(info); 564 pr_info("The CPU configuration topology of the machine is: %d %d %d %d %d %d / %d\n", 565 info->mag[0], info->mag[1], info->mag[2], info->mag[3], 566 info->mag[4], info->mag[5], info->mnest); 567 alloc_masks(info, &socket_info, 1); 568 alloc_masks(info, &book_info, 2); 569 alloc_masks(info, &drawer_info, 3); 570 out: 571 cpumask_set_cpu(0, &cpu_setup_mask); 572 __arch_update_cpu_topology(); 573 __arch_update_dedicated_flag(NULL); 574 } 575 576 static inline int topology_get_mode(int enabled) 577 { 578 if (!enabled) 579 return TOPOLOGY_MODE_SINGLE; 580 return MACHINE_HAS_TOPOLOGY ? TOPOLOGY_MODE_HW : TOPOLOGY_MODE_PACKAGE; 581 } 582 583 static inline int topology_is_enabled(void) 584 { 585 return topology_mode != TOPOLOGY_MODE_SINGLE; 586 } 587 588 static int __init topology_setup(char *str) 589 { 590 bool enabled; 591 int rc; 592 593 rc = kstrtobool(str, &enabled); 594 if (rc) 595 return rc; 596 topology_mode = topology_get_mode(enabled); 597 return 0; 598 } 599 early_param("topology", topology_setup); 600 601 static int topology_ctl_handler(struct ctl_table *ctl, int write, 602 void *buffer, size_t *lenp, loff_t *ppos) 603 { 604 int enabled = topology_is_enabled(); 605 int new_mode; 606 int rc; 607 struct ctl_table ctl_entry = { 608 .procname = ctl->procname, 609 .data = &enabled, 610 .maxlen = sizeof(int), 611 .extra1 = SYSCTL_ZERO, 612 .extra2 = SYSCTL_ONE, 613 }; 614 615 rc = proc_douintvec_minmax(&ctl_entry, write, buffer, lenp, ppos); 616 if (rc < 0 || !write) 617 return rc; 618 619 mutex_lock(&smp_cpu_state_mutex); 620 new_mode = topology_get_mode(enabled); 621 if (topology_mode != new_mode) { 622 topology_mode = new_mode; 623 topology_schedule_update(); 624 } 625 mutex_unlock(&smp_cpu_state_mutex); 626 topology_flush_work(); 627 628 return rc; 629 } 630 631 static struct ctl_table topology_ctl_table[] = { 632 { 633 .procname = "topology", 634 .mode = 0644, 635 .proc_handler = topology_ctl_handler, 636 }, 637 { }, 638 }; 639 640 static struct ctl_table topology_dir_table[] = { 641 { 642 .procname = "s390", 643 .maxlen = 0, 644 .mode = 0555, 645 .child = topology_ctl_table, 646 }, 647 { }, 648 }; 649 650 static int __init topology_init(void) 651 { 652 timer_setup(&topology_timer, topology_timer_fn, TIMER_DEFERRABLE); 653 if (MACHINE_HAS_TOPOLOGY) 654 set_topology_timer(); 655 else 656 topology_update_polarization_simple(); 657 register_sysctl_table(topology_dir_table); 658 return device_create_file(cpu_subsys.dev_root, &dev_attr_dispatching); 659 } 660 device_initcall(topology_init); 661