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/cpuset.h> 12 #include <linux/device.h> 13 #include <linux/kernel.h> 14 #include <linux/sched.h> 15 #include <linux/init.h> 16 #include <linux/delay.h> 17 #include <linux/cpu.h> 18 #include <linux/smp.h> 19 #include <linux/mm.h> 20 #include <asm/sysinfo.h> 21 22 #define PTF_HORIZONTAL (0UL) 23 #define PTF_VERTICAL (1UL) 24 #define PTF_CHECK (2UL) 25 26 struct mask_info { 27 struct mask_info *next; 28 unsigned char id; 29 cpumask_t mask; 30 }; 31 32 static int topology_enabled = 1; 33 static void topology_work_fn(struct work_struct *work); 34 static struct sysinfo_15_1_x *tl_info; 35 static void set_topology_timer(void); 36 static DECLARE_WORK(topology_work, topology_work_fn); 37 /* topology_lock protects the core linked list */ 38 static DEFINE_SPINLOCK(topology_lock); 39 40 static struct mask_info core_info; 41 cpumask_t cpu_core_map[NR_CPUS]; 42 unsigned char cpu_core_id[NR_CPUS]; 43 44 static struct mask_info book_info; 45 cpumask_t cpu_book_map[NR_CPUS]; 46 unsigned char cpu_book_id[NR_CPUS]; 47 48 static cpumask_t cpu_group_map(struct mask_info *info, unsigned int cpu) 49 { 50 cpumask_t mask; 51 52 cpumask_clear(&mask); 53 if (!topology_enabled || !MACHINE_HAS_TOPOLOGY) { 54 cpumask_copy(&mask, cpumask_of(cpu)); 55 return mask; 56 } 57 while (info) { 58 if (cpumask_test_cpu(cpu, &info->mask)) { 59 mask = info->mask; 60 break; 61 } 62 info = info->next; 63 } 64 if (cpumask_empty(&mask)) 65 cpumask_copy(&mask, cpumask_of(cpu)); 66 return mask; 67 } 68 69 static struct mask_info *add_cpus_to_mask(struct topology_cpu *tl_cpu, 70 struct mask_info *book, 71 struct mask_info *core, 72 int one_core_per_cpu) 73 { 74 unsigned int cpu; 75 76 for_each_set_bit(cpu, &tl_cpu->mask[0], TOPOLOGY_CPU_BITS) { 77 unsigned int rcpu; 78 int lcpu; 79 80 rcpu = TOPOLOGY_CPU_BITS - 1 - cpu + tl_cpu->origin; 81 lcpu = smp_find_processor_id(rcpu); 82 if (lcpu >= 0) { 83 cpumask_set_cpu(lcpu, &book->mask); 84 cpu_book_id[lcpu] = book->id; 85 cpumask_set_cpu(lcpu, &core->mask); 86 if (one_core_per_cpu) { 87 cpu_core_id[lcpu] = rcpu; 88 core = core->next; 89 } else { 90 cpu_core_id[lcpu] = core->id; 91 } 92 smp_cpu_set_polarization(lcpu, tl_cpu->pp); 93 } 94 } 95 return core; 96 } 97 98 static void clear_masks(void) 99 { 100 struct mask_info *info; 101 102 info = &core_info; 103 while (info) { 104 cpumask_clear(&info->mask); 105 info = info->next; 106 } 107 info = &book_info; 108 while (info) { 109 cpumask_clear(&info->mask); 110 info = info->next; 111 } 112 } 113 114 static union topology_entry *next_tle(union topology_entry *tle) 115 { 116 if (!tle->nl) 117 return (union topology_entry *)((struct topology_cpu *)tle + 1); 118 return (union topology_entry *)((struct topology_container *)tle + 1); 119 } 120 121 static void __tl_to_cores_generic(struct sysinfo_15_1_x *info) 122 { 123 struct mask_info *core = &core_info; 124 struct mask_info *book = &book_info; 125 union topology_entry *tle, *end; 126 127 tle = info->tle; 128 end = (union topology_entry *)((unsigned long)info + info->length); 129 while (tle < end) { 130 switch (tle->nl) { 131 case 2: 132 book = book->next; 133 book->id = tle->container.id; 134 break; 135 case 1: 136 core = core->next; 137 core->id = tle->container.id; 138 break; 139 case 0: 140 add_cpus_to_mask(&tle->cpu, book, core, 0); 141 break; 142 default: 143 clear_masks(); 144 return; 145 } 146 tle = next_tle(tle); 147 } 148 } 149 150 static void __tl_to_cores_z10(struct sysinfo_15_1_x *info) 151 { 152 struct mask_info *core = &core_info; 153 struct mask_info *book = &book_info; 154 union topology_entry *tle, *end; 155 156 tle = info->tle; 157 end = (union topology_entry *)((unsigned long)info + info->length); 158 while (tle < end) { 159 switch (tle->nl) { 160 case 1: 161 book = book->next; 162 book->id = tle->container.id; 163 break; 164 case 0: 165 core = add_cpus_to_mask(&tle->cpu, book, core, 1); 166 break; 167 default: 168 clear_masks(); 169 return; 170 } 171 tle = next_tle(tle); 172 } 173 } 174 175 static void tl_to_cores(struct sysinfo_15_1_x *info) 176 { 177 struct cpuid cpu_id; 178 179 get_cpu_id(&cpu_id); 180 spin_lock_irq(&topology_lock); 181 clear_masks(); 182 switch (cpu_id.machine) { 183 case 0x2097: 184 case 0x2098: 185 __tl_to_cores_z10(info); 186 break; 187 default: 188 __tl_to_cores_generic(info); 189 } 190 spin_unlock_irq(&topology_lock); 191 } 192 193 static void topology_update_polarization_simple(void) 194 { 195 int cpu; 196 197 mutex_lock(&smp_cpu_state_mutex); 198 for_each_possible_cpu(cpu) 199 smp_cpu_set_polarization(cpu, POLARIZATION_HRZ); 200 mutex_unlock(&smp_cpu_state_mutex); 201 } 202 203 static int ptf(unsigned long fc) 204 { 205 int rc; 206 207 asm volatile( 208 " .insn rre,0xb9a20000,%1,%1\n" 209 " ipm %0\n" 210 " srl %0,28\n" 211 : "=d" (rc) 212 : "d" (fc) : "cc"); 213 return rc; 214 } 215 216 int topology_set_cpu_management(int fc) 217 { 218 int cpu, rc; 219 220 if (!MACHINE_HAS_TOPOLOGY) 221 return -EOPNOTSUPP; 222 if (fc) 223 rc = ptf(PTF_VERTICAL); 224 else 225 rc = ptf(PTF_HORIZONTAL); 226 if (rc) 227 return -EBUSY; 228 for_each_possible_cpu(cpu) 229 smp_cpu_set_polarization(cpu, POLARIZATION_UNKNOWN); 230 return rc; 231 } 232 233 static void update_cpu_core_map(void) 234 { 235 unsigned long flags; 236 int cpu; 237 238 spin_lock_irqsave(&topology_lock, flags); 239 for_each_possible_cpu(cpu) { 240 cpu_core_map[cpu] = cpu_group_map(&core_info, cpu); 241 cpu_book_map[cpu] = cpu_group_map(&book_info, cpu); 242 } 243 spin_unlock_irqrestore(&topology_lock, flags); 244 } 245 246 void store_topology(struct sysinfo_15_1_x *info) 247 { 248 if (topology_max_mnest >= 3) 249 stsi(info, 15, 1, 3); 250 else 251 stsi(info, 15, 1, 2); 252 } 253 254 int arch_update_cpu_topology(void) 255 { 256 struct sysinfo_15_1_x *info = tl_info; 257 struct device *dev; 258 int cpu; 259 260 if (!MACHINE_HAS_TOPOLOGY) { 261 update_cpu_core_map(); 262 topology_update_polarization_simple(); 263 return 0; 264 } 265 store_topology(info); 266 tl_to_cores(info); 267 update_cpu_core_map(); 268 for_each_online_cpu(cpu) { 269 dev = get_cpu_device(cpu); 270 kobject_uevent(&dev->kobj, KOBJ_CHANGE); 271 } 272 return 1; 273 } 274 275 static void topology_work_fn(struct work_struct *work) 276 { 277 rebuild_sched_domains(); 278 } 279 280 void topology_schedule_update(void) 281 { 282 schedule_work(&topology_work); 283 } 284 285 static void topology_timer_fn(unsigned long ignored) 286 { 287 if (ptf(PTF_CHECK)) 288 topology_schedule_update(); 289 set_topology_timer(); 290 } 291 292 static struct timer_list topology_timer = 293 TIMER_DEFERRED_INITIALIZER(topology_timer_fn, 0, 0); 294 295 static atomic_t topology_poll = ATOMIC_INIT(0); 296 297 static void set_topology_timer(void) 298 { 299 if (atomic_add_unless(&topology_poll, -1, 0)) 300 mod_timer(&topology_timer, jiffies + HZ / 10); 301 else 302 mod_timer(&topology_timer, jiffies + HZ * 60); 303 } 304 305 void topology_expect_change(void) 306 { 307 if (!MACHINE_HAS_TOPOLOGY) 308 return; 309 /* This is racy, but it doesn't matter since it is just a heuristic. 310 * Worst case is that we poll in a higher frequency for a bit longer. 311 */ 312 if (atomic_read(&topology_poll) > 60) 313 return; 314 atomic_add(60, &topology_poll); 315 set_topology_timer(); 316 } 317 318 static int __init early_parse_topology(char *p) 319 { 320 if (strncmp(p, "off", 3)) 321 return 0; 322 topology_enabled = 0; 323 return 0; 324 } 325 early_param("topology", early_parse_topology); 326 327 static void __init alloc_masks(struct sysinfo_15_1_x *info, 328 struct mask_info *mask, int offset) 329 { 330 int i, nr_masks; 331 332 nr_masks = info->mag[TOPOLOGY_NR_MAG - offset]; 333 for (i = 0; i < info->mnest - offset; i++) 334 nr_masks *= info->mag[TOPOLOGY_NR_MAG - offset - 1 - i]; 335 nr_masks = max(nr_masks, 1); 336 for (i = 0; i < nr_masks; i++) { 337 mask->next = alloc_bootmem(sizeof(struct mask_info)); 338 mask = mask->next; 339 } 340 } 341 342 void __init s390_init_cpu_topology(void) 343 { 344 struct sysinfo_15_1_x *info; 345 int i; 346 347 if (!MACHINE_HAS_TOPOLOGY) 348 return; 349 tl_info = alloc_bootmem_pages(PAGE_SIZE); 350 info = tl_info; 351 store_topology(info); 352 pr_info("The CPU configuration topology of the machine is:"); 353 for (i = 0; i < TOPOLOGY_NR_MAG; i++) 354 printk(KERN_CONT " %d", info->mag[i]); 355 printk(KERN_CONT " / %d\n", info->mnest); 356 alloc_masks(info, &core_info, 1); 357 alloc_masks(info, &book_info, 2); 358 } 359 360 static int cpu_management; 361 362 static ssize_t dispatching_show(struct device *dev, 363 struct device_attribute *attr, 364 char *buf) 365 { 366 ssize_t count; 367 368 mutex_lock(&smp_cpu_state_mutex); 369 count = sprintf(buf, "%d\n", cpu_management); 370 mutex_unlock(&smp_cpu_state_mutex); 371 return count; 372 } 373 374 static ssize_t dispatching_store(struct device *dev, 375 struct device_attribute *attr, 376 const char *buf, 377 size_t count) 378 { 379 int val, rc; 380 char delim; 381 382 if (sscanf(buf, "%d %c", &val, &delim) != 1) 383 return -EINVAL; 384 if (val != 0 && val != 1) 385 return -EINVAL; 386 rc = 0; 387 get_online_cpus(); 388 mutex_lock(&smp_cpu_state_mutex); 389 if (cpu_management == val) 390 goto out; 391 rc = topology_set_cpu_management(val); 392 if (rc) 393 goto out; 394 cpu_management = val; 395 topology_expect_change(); 396 out: 397 mutex_unlock(&smp_cpu_state_mutex); 398 put_online_cpus(); 399 return rc ? rc : count; 400 } 401 static DEVICE_ATTR(dispatching, 0644, dispatching_show, 402 dispatching_store); 403 404 static ssize_t cpu_polarization_show(struct device *dev, 405 struct device_attribute *attr, char *buf) 406 { 407 int cpu = dev->id; 408 ssize_t count; 409 410 mutex_lock(&smp_cpu_state_mutex); 411 switch (smp_cpu_get_polarization(cpu)) { 412 case POLARIZATION_HRZ: 413 count = sprintf(buf, "horizontal\n"); 414 break; 415 case POLARIZATION_VL: 416 count = sprintf(buf, "vertical:low\n"); 417 break; 418 case POLARIZATION_VM: 419 count = sprintf(buf, "vertical:medium\n"); 420 break; 421 case POLARIZATION_VH: 422 count = sprintf(buf, "vertical:high\n"); 423 break; 424 default: 425 count = sprintf(buf, "unknown\n"); 426 break; 427 } 428 mutex_unlock(&smp_cpu_state_mutex); 429 return count; 430 } 431 static DEVICE_ATTR(polarization, 0444, cpu_polarization_show, NULL); 432 433 static struct attribute *topology_cpu_attrs[] = { 434 &dev_attr_polarization.attr, 435 NULL, 436 }; 437 438 static struct attribute_group topology_cpu_attr_group = { 439 .attrs = topology_cpu_attrs, 440 }; 441 442 int topology_cpu_init(struct cpu *cpu) 443 { 444 return sysfs_create_group(&cpu->dev.kobj, &topology_cpu_attr_group); 445 } 446 447 static int __init topology_init(void) 448 { 449 if (!MACHINE_HAS_TOPOLOGY) { 450 topology_update_polarization_simple(); 451 goto out; 452 } 453 set_topology_timer(); 454 out: 455 update_cpu_core_map(); 456 return device_create_file(cpu_subsys.dev_root, &dev_attr_dispatching); 457 } 458 device_initcall(topology_init); 459