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