1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2009 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #include <sys/systm.h> 27 #include <sys/types.h> 28 #include <sys/param.h> 29 #include <sys/thread.h> 30 #include <sys/cpuvar.h> 31 #include <sys/kmem.h> 32 #include <sys/cmn_err.h> 33 #include <sys/group.h> 34 #include <sys/pg.h> 35 #include <sys/pghw.h> 36 #include <sys/cpu_pm.h> 37 #include <sys/cap_util.h> 38 39 /* 40 * Processor Groups: Hardware sharing relationship layer 41 * 42 * This file implements an extension to Processor Groups to capture 43 * hardware sharing relationships existing between logical CPUs. Examples of 44 * hardware sharing relationships include shared caches on some CMT 45 * procesoor architectures, or shared local memory controllers on NUMA 46 * based system architectures. 47 * 48 * The pghw_t structure represents the extended PG. The first member 49 * of the structure is the generic pg_t with the pghw specific members 50 * following. The generic pg_t *must* remain the first member of the 51 * structure as the code uses casting of structure references to access 52 * the generic pg_t structure elements. 53 * 54 * In addition to the generic CPU grouping, physical PGs have a hardware 55 * sharing relationship enumerated "type", and an instance id. The enumerated 56 * type is defined by the pghw_type_t enumeration, while the instance id 57 * uniquely identifies the sharing instance from among others of the same 58 * hardware sharing type. 59 * 60 * The physical PGs are organized into an overall hierarchy, and are tracked 61 * in a number of different per CPU, and per pghw_type_t type groups. 62 * As an example: 63 * 64 * ------------- 65 * | pg_hw | 66 * | (group_t) | 67 * ------------- 68 * || ============================ 69 * ||\\-----------------------// \\ \\ 70 * || | hwset (PGC_HW_CHIP) | ------------- ------------- 71 * || | (group_t) | | pghw_t | | pghw_t | 72 * || ----------------------- | chip 0 | | chip 1 | 73 * || ------------- ------------- 74 * || \\ \\ \\ \\ \\ \\ \\ \\ 75 * || cpu cpu cpu cpu cpu cpu cpu cpu 76 * || 77 * || ============================ 78 * ||\\-----------------------// \\ \\ 79 * || | hwset (PGC_HW_IPIPE)| ------------- ------------- 80 * || | (group_t) | | pghw_t | | pghw_t | 81 * || ----------------------- | ipipe 0 | | ipipe 1 | 82 * || ------------- ------------- 83 * || \\ \\ \\ \\ 84 * || cpu cpu cpu cpu 85 * ... 86 * 87 * 88 * The top level pg_hw is a group of "hwset" groups. Each hwset holds of group 89 * of physical PGs of the same hardware sharing type. Within each hwset, the 90 * PG's instance id uniquely identifies the grouping relationshsip among other 91 * groupings of the same sharing type. The instance id for a grouping is 92 * platform defined, and in some cases may be used by platform code as a handle 93 * to search for a particular relationship instance. 94 * 95 * Each physical PG (by virtue of the embedded pg_t) contains a group of CPUs 96 * that participate in the sharing relationship. Each CPU also has associated 97 * with it a grouping tracking the PGs in which the CPU belongs. This can be 98 * used to iterate over the various relationships in which the CPU participates 99 * (the CPU's chip, cache, lgroup, etc.). 100 * 101 * The hwsets are created dynamically as new hardware sharing relationship types 102 * are instantiated. They are never destroyed, as once a given relationship 103 * type appears in the system, it is quite likely that at least one instance of 104 * that relationship will always persist as long as the system is running. 105 */ 106 107 static group_t *pg_hw; /* top level pg hw group */ 108 109 /* 110 * Physical PG kstats 111 */ 112 struct pghw_kstat { 113 kstat_named_t pg_id; 114 kstat_named_t pg_class; 115 kstat_named_t pg_ncpus; 116 kstat_named_t pg_instance_id; 117 kstat_named_t pg_hw; 118 kstat_named_t pg_policy; 119 } pghw_kstat = { 120 { "id", KSTAT_DATA_UINT32 }, 121 { "pg_class", KSTAT_DATA_STRING }, 122 { "ncpus", KSTAT_DATA_UINT32 }, 123 { "instance_id", KSTAT_DATA_UINT32 }, 124 { "hardware", KSTAT_DATA_STRING }, 125 { "policy", KSTAT_DATA_STRING }, 126 }; 127 128 kmutex_t pghw_kstat_lock; 129 130 /* 131 * Capacity and Utilization PG kstats 132 * 133 * These kstats are updated one at a time, so we can have a single scratch space 134 * to fill the data. 135 * 136 * kstat fields: 137 * 138 * pgid PG ID for PG described by this kstat 139 * 140 * pg_ncpus Number of CPUs within this PG 141 * 142 * pg_cpus String describing CPUs within this PG 143 * 144 * pg_sharing Name of sharing relationship for this PG 145 * 146 * pg_generation Generation value that increases whenever any CPU leaves 147 * or joins PG. Two kstat snapshots for the same 148 * CPU may only be compared if they have the same 149 * generation 150 * 151 * pg_hw_util Running value of PG utilization for the sharing 152 * relationship 153 * 154 * pg_hw_util_time_running 155 * Total time spent collecting CU data. The time may be 156 * less than wall time if CU counters were stopped for 157 * some time. 158 * 159 * pg_hw_util_time_stopped Total time the CU counters were stopped. 160 * 161 * pg_hw_util_rate Utilization rate, expressed in operations per second. 162 * 163 * pg_hw_util_rate_max Maximum observed value of utilization rate. 164 */ 165 struct pghw_cu_kstat { 166 kstat_named_t pg_id; 167 kstat_named_t pg_ncpus; 168 kstat_named_t pg_generation; 169 kstat_named_t pg_hw_util; 170 kstat_named_t pg_hw_util_time_running; 171 kstat_named_t pg_hw_util_time_stopped; 172 kstat_named_t pg_hw_util_rate; 173 kstat_named_t pg_hw_util_rate_max; 174 kstat_named_t pg_cpus; 175 kstat_named_t pg_sharing; 176 } pghw_cu_kstat = { 177 { "id", KSTAT_DATA_UINT32 }, 178 { "ncpus", KSTAT_DATA_UINT32 }, 179 { "generation", KSTAT_DATA_UINT32 }, 180 { "hw_util", KSTAT_DATA_UINT64 }, 181 { "hw_util_time_running", KSTAT_DATA_UINT64 }, 182 { "hw_util_time_stopped", KSTAT_DATA_UINT64 }, 183 { "hw_util_rate", KSTAT_DATA_UINT64 }, 184 { "hw_util_rate_max", KSTAT_DATA_UINT64 }, 185 { "cpus", KSTAT_DATA_STRING }, 186 { "sharing_relation", KSTAT_DATA_STRING }, 187 }; 188 189 /* 190 * Calculate the string size to represent NCPUS. Allow 5 digits for each CPU ID 191 * plus one space per CPU plus NUL byte in the end. This is only an estimate, 192 * since we try to compress CPU ranges as x-y. In the worst case the string 193 * representation of CPUs may be truncated. 194 */ 195 #define CPUSTR_LEN(ncpus) ((ncpus) * 6) 196 197 /* 198 * Maximum length of the string that represents list of CPUs 199 */ 200 static int pg_cpulist_maxlen = 0; 201 202 static void pghw_kstat_create(pghw_t *); 203 static int pghw_kstat_update(kstat_t *, int); 204 static int pghw_cu_kstat_update(kstat_t *, int); 205 static int cpu2id(void *); 206 207 /* 208 * hwset operations 209 */ 210 static group_t *pghw_set_create(pghw_type_t); 211 static void pghw_set_add(group_t *, pghw_t *); 212 static void pghw_set_remove(group_t *, pghw_t *); 213 214 static void pghw_cpulist_alloc(pghw_t *); 215 static int cpu2id(void *); 216 217 /* 218 * Initialize the physical portion of a hardware PG 219 */ 220 void 221 pghw_init(pghw_t *pg, cpu_t *cp, pghw_type_t hw) 222 { 223 group_t *hwset; 224 225 if ((hwset = pghw_set_lookup(hw)) == NULL) { 226 /* 227 * Haven't seen this hardware type yet 228 */ 229 hwset = pghw_set_create(hw); 230 } 231 232 pghw_set_add(hwset, pg); 233 pg->pghw_hw = hw; 234 pg->pghw_generation = 0; 235 pg->pghw_instance = 236 pg_plat_hw_instance_id(cp, hw); 237 pghw_kstat_create(pg); 238 239 /* 240 * Hardware sharing relationship specific initialization 241 */ 242 switch (pg->pghw_hw) { 243 case PGHW_POW_ACTIVE: 244 pg->pghw_handle = 245 (pghw_handle_t)cpupm_domain_init(cp, CPUPM_DTYPE_ACTIVE); 246 break; 247 case PGHW_POW_IDLE: 248 pg->pghw_handle = 249 (pghw_handle_t)cpupm_domain_init(cp, CPUPM_DTYPE_IDLE); 250 break; 251 default: 252 pg->pghw_handle = (pghw_handle_t)NULL; 253 } 254 } 255 256 /* 257 * Teardown the physical portion of a physical PG 258 */ 259 void 260 pghw_fini(pghw_t *pg) 261 { 262 group_t *hwset; 263 264 hwset = pghw_set_lookup(pg->pghw_hw); 265 ASSERT(hwset != NULL); 266 267 pghw_set_remove(hwset, pg); 268 pg->pghw_instance = (id_t)PGHW_INSTANCE_ANON; 269 pg->pghw_hw = (pghw_type_t)-1; 270 271 if (pg->pghw_kstat != NULL) 272 kstat_delete(pg->pghw_kstat); 273 274 /* 275 * Destroy string representation of CPUs 276 */ 277 if (pg->pghw_cpulist != NULL) { 278 kmem_free(pg->pghw_cpulist, 279 pg->pghw_cpulist_len); 280 pg->pghw_cpulist = NULL; 281 } 282 283 if (pg->pghw_cu_kstat != NULL) 284 kstat_delete(pg->pghw_cu_kstat); 285 } 286 287 /* 288 * Find an existing physical PG in which to place 289 * the given CPU for the specified hardware sharing 290 * relationship 291 */ 292 pghw_t * 293 pghw_place_cpu(cpu_t *cp, pghw_type_t hw) 294 { 295 group_t *hwset; 296 297 if ((hwset = pghw_set_lookup(hw)) == NULL) { 298 return (NULL); 299 } 300 301 return ((pghw_t *)pg_cpu_find_pg(cp, hwset)); 302 } 303 304 /* 305 * Find the pg representing the hw sharing relationship in which 306 * cp belongs 307 */ 308 pghw_t * 309 pghw_find_pg(cpu_t *cp, pghw_type_t hw) 310 { 311 group_iter_t i; 312 pghw_t *pg; 313 314 group_iter_init(&i); 315 while ((pg = group_iterate(&cp->cpu_pg->pgs, &i)) != NULL) { 316 if (pg->pghw_hw == hw) 317 return (pg); 318 } 319 return (NULL); 320 } 321 322 /* 323 * Find the PG of the given hardware sharing relationship 324 * type with the given instance id 325 */ 326 pghw_t * 327 pghw_find_by_instance(id_t id, pghw_type_t hw) 328 { 329 group_iter_t i; 330 group_t *set; 331 pghw_t *pg; 332 333 set = pghw_set_lookup(hw); 334 if (!set) 335 return (NULL); 336 337 group_iter_init(&i); 338 while ((pg = group_iterate(set, &i)) != NULL) { 339 if (pg->pghw_instance == id) 340 return (pg); 341 } 342 return (NULL); 343 } 344 345 /* 346 * CPUs physical ID cache creation / destruction 347 * The cache's elements are initialized to the CPU's id 348 */ 349 void 350 pghw_physid_create(cpu_t *cp) 351 { 352 int i; 353 354 cp->cpu_physid = kmem_alloc(sizeof (cpu_physid_t), KM_SLEEP); 355 356 for (i = 0; i < (sizeof (cpu_physid_t) / sizeof (id_t)); i++) { 357 ((id_t *)cp->cpu_physid)[i] = cp->cpu_id; 358 } 359 } 360 361 void 362 pghw_physid_destroy(cpu_t *cp) 363 { 364 if (cp->cpu_physid) { 365 kmem_free(cp->cpu_physid, sizeof (cpu_physid_t)); 366 cp->cpu_physid = NULL; 367 } 368 } 369 370 /* 371 * Create a new, empty hwset. 372 * This routine may block, and must not be called from any 373 * paused CPU context. 374 */ 375 static group_t * 376 pghw_set_create(pghw_type_t hw) 377 { 378 group_t *g; 379 int ret; 380 381 /* 382 * Create the top level PG hw group if it doesn't already exist 383 * This is a "set" of hardware sets, that is ordered (and indexed) 384 * by the pghw_type_t enum. 385 */ 386 if (pg_hw == NULL) { 387 pg_hw = kmem_alloc(sizeof (group_t), KM_SLEEP); 388 group_create(pg_hw); 389 group_expand(pg_hw, (uint_t)PGHW_NUM_COMPONENTS); 390 } 391 392 /* 393 * Create the new hwset 394 * Add it to the top level pg_hw group. 395 */ 396 g = kmem_alloc(sizeof (group_t), KM_SLEEP); 397 group_create(g); 398 399 ret = group_add_at(pg_hw, g, (uint_t)hw); 400 ASSERT(ret == 0); 401 402 return (g); 403 } 404 405 /* 406 * Find the hwset associated with the given hardware sharing type 407 */ 408 group_t * 409 pghw_set_lookup(pghw_type_t hw) 410 { 411 group_t *hwset; 412 413 if (pg_hw == NULL) 414 return (NULL); 415 416 hwset = GROUP_ACCESS(pg_hw, (uint_t)hw); 417 return (hwset); 418 } 419 420 /* 421 * Add a PG to a hwset 422 */ 423 static void 424 pghw_set_add(group_t *hwset, pghw_t *pg) 425 { 426 (void) group_add(hwset, pg, GRP_RESIZE); 427 } 428 429 /* 430 * Remove a PG from a hwset 431 */ 432 static void 433 pghw_set_remove(group_t *hwset, pghw_t *pg) 434 { 435 int result; 436 437 result = group_remove(hwset, pg, GRP_RESIZE); 438 ASSERT(result == 0); 439 } 440 441 /* 442 * Return a string name given a pg_hw sharing type 443 */ 444 char * 445 pghw_type_string(pghw_type_t hw) 446 { 447 switch (hw) { 448 case PGHW_IPIPE: 449 return ("Integer Pipeline"); 450 case PGHW_CACHE: 451 return ("Cache"); 452 case PGHW_FPU: 453 return ("Floating Point Unit"); 454 case PGHW_MPIPE: 455 return ("Data Pipe to memory"); 456 case PGHW_CHIP: 457 return ("Socket"); 458 case PGHW_MEMORY: 459 return ("Memory"); 460 case PGHW_POW_ACTIVE: 461 return ("CPU PM Active Power Domain"); 462 case PGHW_POW_IDLE: 463 return ("CPU PM Idle Power Domain"); 464 default: 465 return ("unknown"); 466 } 467 } 468 469 /* 470 * Return a short string name given a pg_hw sharing type 471 */ 472 char * 473 pghw_type_shortstring(pghw_type_t hw) 474 { 475 switch (hw) { 476 case PGHW_IPIPE: 477 return ("instr_pipeline"); 478 case PGHW_CACHE: 479 return ("Cache"); 480 case PGHW_FPU: 481 return ("FPU"); 482 case PGHW_MPIPE: 483 return ("memory_pipeline"); 484 case PGHW_CHIP: 485 return ("Socket"); 486 case PGHW_MEMORY: 487 return ("Memory"); 488 case PGHW_POW_ACTIVE: 489 return ("CPU_PM_Active"); 490 case PGHW_POW_IDLE: 491 return ("CPU_PM_Idle"); 492 default: 493 return ("unknown"); 494 } 495 } 496 497 /* 498 * Create / Update routines for PG hw kstats 499 * 500 * It is the intention of these kstats to provide some level 501 * of informational / debugging observability into the types 502 * and nature of the system's detected hardware sharing relationships 503 */ 504 void 505 pghw_kstat_create(pghw_t *pg) 506 { 507 char *class = pghw_type_string(pg->pghw_hw); 508 509 /* 510 * Create a physical pg kstat 511 */ 512 if ((pg->pghw_kstat = kstat_create("pg", ((pg_t *)pg)->pg_id, 513 "pg", "pg", 514 KSTAT_TYPE_NAMED, 515 sizeof (pghw_kstat) / sizeof (kstat_named_t), 516 KSTAT_FLAG_VIRTUAL)) != NULL) { 517 /* Class string, hw string, and policy string */ 518 pg->pghw_kstat->ks_data_size += PG_CLASS_NAME_MAX; 519 pg->pghw_kstat->ks_data_size += PGHW_KSTAT_STR_LEN_MAX; 520 pg->pghw_kstat->ks_data_size += PGHW_KSTAT_STR_LEN_MAX; 521 pg->pghw_kstat->ks_lock = &pghw_kstat_lock; 522 pg->pghw_kstat->ks_data = &pghw_kstat; 523 pg->pghw_kstat->ks_update = pghw_kstat_update; 524 pg->pghw_kstat->ks_private = pg; 525 kstat_install(pg->pghw_kstat); 526 } 527 528 if (pg_cpulist_maxlen == 0) 529 pg_cpulist_maxlen = CPUSTR_LEN(max_ncpus); 530 531 /* 532 * Create a physical pg kstat 533 */ 534 if ((pg->pghw_cu_kstat = kstat_create("pg", ((pg_t *)pg)->pg_id, 535 "hardware", class, 536 KSTAT_TYPE_NAMED, 537 sizeof (pghw_cu_kstat) / sizeof (kstat_named_t), 538 KSTAT_FLAG_VIRTUAL)) != NULL) { 539 pg->pghw_cu_kstat->ks_lock = &pghw_kstat_lock; 540 pg->pghw_cu_kstat->ks_data = &pghw_cu_kstat; 541 pg->pghw_cu_kstat->ks_update = pghw_cu_kstat_update; 542 pg->pghw_cu_kstat->ks_private = pg; 543 pg->pghw_cu_kstat->ks_data_size += strlen(class) + 1; 544 /* Allow space for CPU strings */ 545 pg->pghw_cu_kstat->ks_data_size += PGHW_KSTAT_STR_LEN_MAX; 546 pg->pghw_cu_kstat->ks_data_size += pg_cpulist_maxlen; 547 kstat_install(pg->pghw_cu_kstat); 548 } 549 } 550 551 int 552 pghw_kstat_update(kstat_t *ksp, int rw) 553 { 554 struct pghw_kstat *pgsp = &pghw_kstat; 555 pghw_t *pg = ksp->ks_private; 556 557 if (rw == KSTAT_WRITE) 558 return (EACCES); 559 560 pgsp->pg_id.value.ui32 = ((pg_t *)pg)->pg_id; 561 pgsp->pg_ncpus.value.ui32 = GROUP_SIZE(&((pg_t *)pg)->pg_cpus); 562 pgsp->pg_instance_id.value.ui32 = pg->pghw_instance; 563 kstat_named_setstr(&pgsp->pg_class, ((pg_t *)pg)->pg_class->pgc_name); 564 kstat_named_setstr(&pgsp->pg_hw, pghw_type_string(pg->pghw_hw)); 565 kstat_named_setstr(&pgsp->pg_policy, pg_policy_name((pg_t *)pg)); 566 return (0); 567 } 568 569 int 570 pghw_cu_kstat_update(kstat_t *ksp, int rw) 571 { 572 struct pghw_cu_kstat *pgsp = &pghw_cu_kstat; 573 pghw_t *pg = ksp->ks_private; 574 pghw_util_t *hw_util = &pg->pghw_stats; 575 576 if (rw == KSTAT_WRITE) 577 return (EACCES); 578 579 pgsp->pg_id.value.ui32 = ((pg_t *)pg)->pg_id; 580 pgsp->pg_ncpus.value.ui32 = GROUP_SIZE(&((pg_t *)pg)->pg_cpus); 581 582 /* 583 * Allocate memory for the string representing the list of CPUs in PG. 584 * This memory should persist past the call to pghw_cu_kstat_update() 585 * since the kstat snapshot routine will reference this memory. 586 */ 587 pghw_cpulist_alloc(pg); 588 589 if (pg->pghw_kstat_gen != pg->pghw_generation) { 590 /* 591 * PG kstat generation number is out of sync with PG's 592 * generation mumber. It means that some CPUs could have joined 593 * or left PG and it is not possible to compare the numbers 594 * obtained before and after the generation change. 595 * 596 * Reset the maximum utilization rate and start computing it 597 * from scratch. 598 */ 599 hw_util->pghw_util = 0; 600 hw_util->pghw_rate_max = 0; 601 pg->pghw_kstat_gen = pg->pghw_generation; 602 } 603 604 /* 605 * We can't block on CPU lock because when PG is destroyed (under 606 * cpu_lock) it tries to delete this kstat and it will wait for us to 607 * complete which will never happen since we are waiting for cpu_lock to 608 * drop. Deadlocks are fun! 609 */ 610 if (mutex_tryenter(&cpu_lock)) { 611 if (pg->pghw_cpulist != NULL && 612 *(pg->pghw_cpulist) == '\0') { 613 (void) group2intlist(&(((pg_t *)pg)->pg_cpus), 614 pg->pghw_cpulist, pg->pghw_cpulist_len, cpu2id); 615 } 616 cu_pg_update(pg); 617 mutex_exit(&cpu_lock); 618 } 619 620 pgsp->pg_generation.value.ui32 = pg->pghw_kstat_gen; 621 pgsp->pg_hw_util.value.ui64 = hw_util->pghw_util; 622 pgsp->pg_hw_util_time_running.value.ui64 = hw_util->pghw_time_running; 623 pgsp->pg_hw_util_time_stopped.value.ui64 = hw_util->pghw_time_stopped; 624 pgsp->pg_hw_util_rate.value.ui64 = hw_util->pghw_rate; 625 pgsp->pg_hw_util_rate_max.value.ui64 = hw_util->pghw_rate_max; 626 if (pg->pghw_cpulist != NULL) 627 kstat_named_setstr(&pgsp->pg_cpus, pg->pghw_cpulist); 628 else 629 kstat_named_setstr(&pgsp->pg_cpus, ""); 630 631 kstat_named_setstr(&pgsp->pg_sharing, pghw_type_string(pg->pghw_hw)); 632 633 return (0); 634 } 635 636 /* 637 * Update the string representation of CPUs in PG (pg->pghw_cpulist). 638 * The string representation is used for kstats. 639 * 640 * The string is allocated if it has not already been or if it is already 641 * allocated and PG has more CPUs now. If PG has smaller or equal number of 642 * CPUs, but the actual CPUs may have changed, the string is reset to the empty 643 * string causes the string representation to be recreated. The pghw_generation 644 * field is used to detect whether CPUs within the pg may have changed. 645 */ 646 static void 647 pghw_cpulist_alloc(pghw_t *pg) 648 { 649 uint_t ncpus = GROUP_SIZE(&((pg_t *)pg)->pg_cpus); 650 size_t len = CPUSTR_LEN(ncpus); 651 652 /* 653 * If the pghw_cpulist string is already allocated we need to make sure 654 * that it has sufficient length. Also if the set of CPUs may have 655 * changed, we need to re-generate the string. 656 */ 657 if (pg->pghw_cpulist != NULL && 658 pg->pghw_kstat_gen != pg->pghw_generation) { 659 if (len <= pg->pghw_cpulist_len) { 660 /* 661 * There is sufficient space in the pghw_cpulist for 662 * the new set of CPUs. Just clear the string to trigger 663 * re-generation of list of CPUs 664 */ 665 *(pg->pghw_cpulist) = '\0'; 666 } else { 667 /* 668 * There is, potentially, insufficient space in 669 * pghw_cpulist, so reallocate the string. 670 */ 671 ASSERT(strlen(pg->pghw_cpulist) < pg->pghw_cpulist_len); 672 kmem_free(pg->pghw_cpulist, pg->pghw_cpulist_len); 673 pg->pghw_cpulist = NULL; 674 pg->pghw_cpulist_len = 0; 675 } 676 } 677 678 if (pg->pghw_cpulist == NULL) { 679 /* 680 * Allocate space to hold cpulist. 681 * 682 * Length can not be bigger that the maximum space we have 683 * allowed for the kstat buffer 684 */ 685 if (len > pg_cpulist_maxlen) 686 len = pg_cpulist_maxlen; 687 if (len > 0) { 688 pg->pghw_cpulist = kmem_zalloc(len, KM_NOSLEEP); 689 if (pg->pghw_cpulist != NULL) 690 pg->pghw_cpulist_len = len; 691 } 692 } 693 } 694 695 static int 696 cpu2id(void *v) 697 { 698 cpu_t *cp = (cpu_t *)v; 699 700 ASSERT(v != NULL); 701 702 return (cp->cpu_id); 703 } 704