1 /*- 2 * Copyright (c) 2002-2005, 2009 Jeffrey Roberson <jeff@FreeBSD.org> 3 * Copyright (c) 2004, 2005 Bosko Milekic <bmilekic@FreeBSD.org> 4 * Copyright (c) 2004-2006 Robert N. M. Watson 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice unmodified, this list of conditions, and the following 12 * disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 /* 30 * uma_core.c Implementation of the Universal Memory allocator 31 * 32 * This allocator is intended to replace the multitude of similar object caches 33 * in the standard FreeBSD kernel. The intent is to be flexible as well as 34 * effecient. A primary design goal is to return unused memory to the rest of 35 * the system. This will make the system as a whole more flexible due to the 36 * ability to move memory to subsystems which most need it instead of leaving 37 * pools of reserved memory unused. 38 * 39 * The basic ideas stem from similar slab/zone based allocators whose algorithms 40 * are well known. 41 * 42 */ 43 44 /* 45 * TODO: 46 * - Improve memory usage for large allocations 47 * - Investigate cache size adjustments 48 */ 49 50 #include <sys/cdefs.h> 51 __FBSDID("$FreeBSD$"); 52 53 /* I should really use ktr.. */ 54 /* 55 #define UMA_DEBUG 1 56 #define UMA_DEBUG_ALLOC 1 57 #define UMA_DEBUG_ALLOC_1 1 58 */ 59 60 #include "opt_ddb.h" 61 #include "opt_param.h" 62 #include "opt_vm.h" 63 64 #include <sys/param.h> 65 #include <sys/systm.h> 66 #include <sys/kernel.h> 67 #include <sys/types.h> 68 #include <sys/queue.h> 69 #include <sys/malloc.h> 70 #include <sys/ktr.h> 71 #include <sys/lock.h> 72 #include <sys/sysctl.h> 73 #include <sys/mutex.h> 74 #include <sys/proc.h> 75 #include <sys/rwlock.h> 76 #include <sys/sbuf.h> 77 #include <sys/smp.h> 78 #include <sys/vmmeter.h> 79 80 #include <vm/vm.h> 81 #include <vm/vm_object.h> 82 #include <vm/vm_page.h> 83 #include <vm/vm_pageout.h> 84 #include <vm/vm_param.h> 85 #include <vm/vm_map.h> 86 #include <vm/vm_kern.h> 87 #include <vm/vm_extern.h> 88 #include <vm/uma.h> 89 #include <vm/uma_int.h> 90 #include <vm/uma_dbg.h> 91 92 #include <ddb/ddb.h> 93 94 #ifdef DEBUG_MEMGUARD 95 #include <vm/memguard.h> 96 #endif 97 98 /* 99 * This is the zone and keg from which all zones are spawned. The idea is that 100 * even the zone & keg heads are allocated from the allocator, so we use the 101 * bss section to bootstrap us. 102 */ 103 static struct uma_keg masterkeg; 104 static struct uma_zone masterzone_k; 105 static struct uma_zone masterzone_z; 106 static uma_zone_t kegs = &masterzone_k; 107 static uma_zone_t zones = &masterzone_z; 108 109 /* This is the zone from which all of uma_slab_t's are allocated. */ 110 static uma_zone_t slabzone; 111 static uma_zone_t slabrefzone; /* With refcounters (for UMA_ZONE_REFCNT) */ 112 113 /* 114 * The initial hash tables come out of this zone so they can be allocated 115 * prior to malloc coming up. 116 */ 117 static uma_zone_t hashzone; 118 119 /* The boot-time adjusted value for cache line alignment. */ 120 int uma_align_cache = 64 - 1; 121 122 static MALLOC_DEFINE(M_UMAHASH, "UMAHash", "UMA Hash Buckets"); 123 124 /* 125 * Are we allowed to allocate buckets? 126 */ 127 static int bucketdisable = 1; 128 129 /* Linked list of all kegs in the system */ 130 static LIST_HEAD(,uma_keg) uma_kegs = LIST_HEAD_INITIALIZER(uma_kegs); 131 132 /* This mutex protects the keg list */ 133 static struct mtx uma_mtx; 134 135 /* Linked list of boot time pages */ 136 static LIST_HEAD(,uma_slab) uma_boot_pages = 137 LIST_HEAD_INITIALIZER(uma_boot_pages); 138 139 /* This mutex protects the boot time pages list */ 140 static struct mtx uma_boot_pages_mtx; 141 142 /* Is the VM done starting up? */ 143 static int booted = 0; 144 #define UMA_STARTUP 1 145 #define UMA_STARTUP2 2 146 147 /* Maximum number of allowed items-per-slab if the slab header is OFFPAGE */ 148 static u_int uma_max_ipers; 149 static u_int uma_max_ipers_ref; 150 151 /* 152 * This is the handle used to schedule events that need to happen 153 * outside of the allocation fast path. 154 */ 155 static struct callout uma_callout; 156 #define UMA_TIMEOUT 20 /* Seconds for callout interval. */ 157 158 /* 159 * This structure is passed as the zone ctor arg so that I don't have to create 160 * a special allocation function just for zones. 161 */ 162 struct uma_zctor_args { 163 const char *name; 164 size_t size; 165 uma_ctor ctor; 166 uma_dtor dtor; 167 uma_init uminit; 168 uma_fini fini; 169 uma_keg_t keg; 170 int align; 171 u_int32_t flags; 172 }; 173 174 struct uma_kctor_args { 175 uma_zone_t zone; 176 size_t size; 177 uma_init uminit; 178 uma_fini fini; 179 int align; 180 u_int32_t flags; 181 }; 182 183 struct uma_bucket_zone { 184 uma_zone_t ubz_zone; 185 char *ubz_name; 186 int ubz_entries; 187 }; 188 189 #define BUCKET_MAX 128 190 191 struct uma_bucket_zone bucket_zones[] = { 192 { NULL, "16 Bucket", 16 }, 193 { NULL, "32 Bucket", 32 }, 194 { NULL, "64 Bucket", 64 }, 195 { NULL, "128 Bucket", 128 }, 196 { NULL, NULL, 0} 197 }; 198 199 #define BUCKET_SHIFT 4 200 #define BUCKET_ZONES ((BUCKET_MAX >> BUCKET_SHIFT) + 1) 201 202 /* 203 * bucket_size[] maps requested bucket sizes to zones that allocate a bucket 204 * of approximately the right size. 205 */ 206 static uint8_t bucket_size[BUCKET_ZONES]; 207 208 /* 209 * Flags and enumerations to be passed to internal functions. 210 */ 211 enum zfreeskip { SKIP_NONE, SKIP_DTOR, SKIP_FINI }; 212 213 #define ZFREE_STATFAIL 0x00000001 /* Update zone failure statistic. */ 214 #define ZFREE_STATFREE 0x00000002 /* Update zone free statistic. */ 215 216 /* Prototypes.. */ 217 218 static void *noobj_alloc(uma_zone_t, int, u_int8_t *, int); 219 static void *page_alloc(uma_zone_t, int, u_int8_t *, int); 220 static void *startup_alloc(uma_zone_t, int, u_int8_t *, int); 221 static void page_free(void *, int, u_int8_t); 222 static uma_slab_t keg_alloc_slab(uma_keg_t, uma_zone_t, int); 223 static void cache_drain(uma_zone_t); 224 static void bucket_drain(uma_zone_t, uma_bucket_t); 225 static void bucket_cache_drain(uma_zone_t zone); 226 static int keg_ctor(void *, int, void *, int); 227 static void keg_dtor(void *, int, void *); 228 static int zone_ctor(void *, int, void *, int); 229 static void zone_dtor(void *, int, void *); 230 static int zero_init(void *, int, int); 231 static void keg_small_init(uma_keg_t keg); 232 static void keg_large_init(uma_keg_t keg); 233 static void zone_foreach(void (*zfunc)(uma_zone_t)); 234 static void zone_timeout(uma_zone_t zone); 235 static int hash_alloc(struct uma_hash *); 236 static int hash_expand(struct uma_hash *, struct uma_hash *); 237 static void hash_free(struct uma_hash *hash); 238 static void uma_timeout(void *); 239 static void uma_startup3(void); 240 static void *zone_alloc_item(uma_zone_t, void *, int); 241 static void zone_free_item(uma_zone_t, void *, void *, enum zfreeskip, 242 int); 243 static void bucket_enable(void); 244 static void bucket_init(void); 245 static uma_bucket_t bucket_alloc(int, int); 246 static void bucket_free(uma_bucket_t); 247 static void bucket_zone_drain(void); 248 static int zone_alloc_bucket(uma_zone_t zone, int flags); 249 static uma_slab_t zone_fetch_slab(uma_zone_t zone, uma_keg_t last, int flags); 250 static uma_slab_t zone_fetch_slab_multi(uma_zone_t zone, uma_keg_t last, int flags); 251 static void *slab_alloc_item(uma_zone_t zone, uma_slab_t slab); 252 static uma_keg_t uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit, 253 uma_fini fini, int align, u_int32_t flags); 254 static inline void zone_relock(uma_zone_t zone, uma_keg_t keg); 255 static inline void keg_relock(uma_keg_t keg, uma_zone_t zone); 256 257 void uma_print_zone(uma_zone_t); 258 void uma_print_stats(void); 259 static int sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS); 260 static int sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS); 261 262 SYSINIT(uma_startup3, SI_SUB_VM_CONF, SI_ORDER_SECOND, uma_startup3, NULL); 263 264 SYSCTL_PROC(_vm, OID_AUTO, zone_count, CTLFLAG_RD|CTLTYPE_INT, 265 0, 0, sysctl_vm_zone_count, "I", "Number of UMA zones"); 266 267 SYSCTL_PROC(_vm, OID_AUTO, zone_stats, CTLFLAG_RD|CTLTYPE_STRUCT, 268 0, 0, sysctl_vm_zone_stats, "s,struct uma_type_header", "Zone Stats"); 269 270 static int zone_warnings = 1; 271 TUNABLE_INT("vm.zone_warnings", &zone_warnings); 272 SYSCTL_INT(_vm, OID_AUTO, zone_warnings, CTLFLAG_RW, &zone_warnings, 0, 273 "Warn when UMA zones becomes full"); 274 275 /* 276 * This routine checks to see whether or not it's safe to enable buckets. 277 */ 278 279 static void 280 bucket_enable(void) 281 { 282 bucketdisable = vm_page_count_min(); 283 } 284 285 /* 286 * Initialize bucket_zones, the array of zones of buckets of various sizes. 287 * 288 * For each zone, calculate the memory required for each bucket, consisting 289 * of the header and an array of pointers. Initialize bucket_size[] to point 290 * the range of appropriate bucket sizes at the zone. 291 */ 292 static void 293 bucket_init(void) 294 { 295 struct uma_bucket_zone *ubz; 296 int i; 297 int j; 298 299 for (i = 0, j = 0; bucket_zones[j].ubz_entries != 0; j++) { 300 int size; 301 302 ubz = &bucket_zones[j]; 303 size = roundup(sizeof(struct uma_bucket), sizeof(void *)); 304 size += sizeof(void *) * ubz->ubz_entries; 305 ubz->ubz_zone = uma_zcreate(ubz->ubz_name, size, 306 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 307 UMA_ZFLAG_INTERNAL | UMA_ZFLAG_BUCKET); 308 for (; i <= ubz->ubz_entries; i += (1 << BUCKET_SHIFT)) 309 bucket_size[i >> BUCKET_SHIFT] = j; 310 } 311 } 312 313 /* 314 * Given a desired number of entries for a bucket, return the zone from which 315 * to allocate the bucket. 316 */ 317 static struct uma_bucket_zone * 318 bucket_zone_lookup(int entries) 319 { 320 int idx; 321 322 idx = howmany(entries, 1 << BUCKET_SHIFT); 323 return (&bucket_zones[bucket_size[idx]]); 324 } 325 326 static uma_bucket_t 327 bucket_alloc(int entries, int bflags) 328 { 329 struct uma_bucket_zone *ubz; 330 uma_bucket_t bucket; 331 332 /* 333 * This is to stop us from allocating per cpu buckets while we're 334 * running out of vm.boot_pages. Otherwise, we would exhaust the 335 * boot pages. This also prevents us from allocating buckets in 336 * low memory situations. 337 */ 338 if (bucketdisable) 339 return (NULL); 340 341 ubz = bucket_zone_lookup(entries); 342 bucket = zone_alloc_item(ubz->ubz_zone, NULL, bflags); 343 if (bucket) { 344 #ifdef INVARIANTS 345 bzero(bucket->ub_bucket, sizeof(void *) * ubz->ubz_entries); 346 #endif 347 bucket->ub_cnt = 0; 348 bucket->ub_entries = ubz->ubz_entries; 349 } 350 351 return (bucket); 352 } 353 354 static void 355 bucket_free(uma_bucket_t bucket) 356 { 357 struct uma_bucket_zone *ubz; 358 359 ubz = bucket_zone_lookup(bucket->ub_entries); 360 zone_free_item(ubz->ubz_zone, bucket, NULL, SKIP_NONE, 361 ZFREE_STATFREE); 362 } 363 364 static void 365 bucket_zone_drain(void) 366 { 367 struct uma_bucket_zone *ubz; 368 369 for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++) 370 zone_drain(ubz->ubz_zone); 371 } 372 373 static void 374 zone_log_warning(uma_zone_t zone) 375 { 376 static const struct timeval warninterval = { 300, 0 }; 377 378 if (!zone_warnings || zone->uz_warning == NULL) 379 return; 380 381 if (ratecheck(&zone->uz_ratecheck, &warninterval)) 382 printf("[zone: %s] %s\n", zone->uz_name, zone->uz_warning); 383 } 384 385 static inline uma_keg_t 386 zone_first_keg(uma_zone_t zone) 387 { 388 389 return (LIST_FIRST(&zone->uz_kegs)->kl_keg); 390 } 391 392 static void 393 zone_foreach_keg(uma_zone_t zone, void (*kegfn)(uma_keg_t)) 394 { 395 uma_klink_t klink; 396 397 LIST_FOREACH(klink, &zone->uz_kegs, kl_link) 398 kegfn(klink->kl_keg); 399 } 400 401 /* 402 * Routine called by timeout which is used to fire off some time interval 403 * based calculations. (stats, hash size, etc.) 404 * 405 * Arguments: 406 * arg Unused 407 * 408 * Returns: 409 * Nothing 410 */ 411 static void 412 uma_timeout(void *unused) 413 { 414 bucket_enable(); 415 zone_foreach(zone_timeout); 416 417 /* Reschedule this event */ 418 callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL); 419 } 420 421 /* 422 * Routine to perform timeout driven calculations. This expands the 423 * hashes and does per cpu statistics aggregation. 424 * 425 * Returns nothing. 426 */ 427 static void 428 keg_timeout(uma_keg_t keg) 429 { 430 431 KEG_LOCK(keg); 432 /* 433 * Expand the keg hash table. 434 * 435 * This is done if the number of slabs is larger than the hash size. 436 * What I'm trying to do here is completely reduce collisions. This 437 * may be a little aggressive. Should I allow for two collisions max? 438 */ 439 if (keg->uk_flags & UMA_ZONE_HASH && 440 keg->uk_pages / keg->uk_ppera >= keg->uk_hash.uh_hashsize) { 441 struct uma_hash newhash; 442 struct uma_hash oldhash; 443 int ret; 444 445 /* 446 * This is so involved because allocating and freeing 447 * while the keg lock is held will lead to deadlock. 448 * I have to do everything in stages and check for 449 * races. 450 */ 451 newhash = keg->uk_hash; 452 KEG_UNLOCK(keg); 453 ret = hash_alloc(&newhash); 454 KEG_LOCK(keg); 455 if (ret) { 456 if (hash_expand(&keg->uk_hash, &newhash)) { 457 oldhash = keg->uk_hash; 458 keg->uk_hash = newhash; 459 } else 460 oldhash = newhash; 461 462 KEG_UNLOCK(keg); 463 hash_free(&oldhash); 464 KEG_LOCK(keg); 465 } 466 } 467 KEG_UNLOCK(keg); 468 } 469 470 static void 471 zone_timeout(uma_zone_t zone) 472 { 473 474 zone_foreach_keg(zone, &keg_timeout); 475 } 476 477 /* 478 * Allocate and zero fill the next sized hash table from the appropriate 479 * backing store. 480 * 481 * Arguments: 482 * hash A new hash structure with the old hash size in uh_hashsize 483 * 484 * Returns: 485 * 1 on sucess and 0 on failure. 486 */ 487 static int 488 hash_alloc(struct uma_hash *hash) 489 { 490 int oldsize; 491 int alloc; 492 493 oldsize = hash->uh_hashsize; 494 495 /* We're just going to go to a power of two greater */ 496 if (oldsize) { 497 hash->uh_hashsize = oldsize * 2; 498 alloc = sizeof(hash->uh_slab_hash[0]) * hash->uh_hashsize; 499 hash->uh_slab_hash = (struct slabhead *)malloc(alloc, 500 M_UMAHASH, M_NOWAIT); 501 } else { 502 alloc = sizeof(hash->uh_slab_hash[0]) * UMA_HASH_SIZE_INIT; 503 hash->uh_slab_hash = zone_alloc_item(hashzone, NULL, 504 M_WAITOK); 505 hash->uh_hashsize = UMA_HASH_SIZE_INIT; 506 } 507 if (hash->uh_slab_hash) { 508 bzero(hash->uh_slab_hash, alloc); 509 hash->uh_hashmask = hash->uh_hashsize - 1; 510 return (1); 511 } 512 513 return (0); 514 } 515 516 /* 517 * Expands the hash table for HASH zones. This is done from zone_timeout 518 * to reduce collisions. This must not be done in the regular allocation 519 * path, otherwise, we can recurse on the vm while allocating pages. 520 * 521 * Arguments: 522 * oldhash The hash you want to expand 523 * newhash The hash structure for the new table 524 * 525 * Returns: 526 * Nothing 527 * 528 * Discussion: 529 */ 530 static int 531 hash_expand(struct uma_hash *oldhash, struct uma_hash *newhash) 532 { 533 uma_slab_t slab; 534 int hval; 535 int i; 536 537 if (!newhash->uh_slab_hash) 538 return (0); 539 540 if (oldhash->uh_hashsize >= newhash->uh_hashsize) 541 return (0); 542 543 /* 544 * I need to investigate hash algorithms for resizing without a 545 * full rehash. 546 */ 547 548 for (i = 0; i < oldhash->uh_hashsize; i++) 549 while (!SLIST_EMPTY(&oldhash->uh_slab_hash[i])) { 550 slab = SLIST_FIRST(&oldhash->uh_slab_hash[i]); 551 SLIST_REMOVE_HEAD(&oldhash->uh_slab_hash[i], us_hlink); 552 hval = UMA_HASH(newhash, slab->us_data); 553 SLIST_INSERT_HEAD(&newhash->uh_slab_hash[hval], 554 slab, us_hlink); 555 } 556 557 return (1); 558 } 559 560 /* 561 * Free the hash bucket to the appropriate backing store. 562 * 563 * Arguments: 564 * slab_hash The hash bucket we're freeing 565 * hashsize The number of entries in that hash bucket 566 * 567 * Returns: 568 * Nothing 569 */ 570 static void 571 hash_free(struct uma_hash *hash) 572 { 573 if (hash->uh_slab_hash == NULL) 574 return; 575 if (hash->uh_hashsize == UMA_HASH_SIZE_INIT) 576 zone_free_item(hashzone, 577 hash->uh_slab_hash, NULL, SKIP_NONE, ZFREE_STATFREE); 578 else 579 free(hash->uh_slab_hash, M_UMAHASH); 580 } 581 582 /* 583 * Frees all outstanding items in a bucket 584 * 585 * Arguments: 586 * zone The zone to free to, must be unlocked. 587 * bucket The free/alloc bucket with items, cpu queue must be locked. 588 * 589 * Returns: 590 * Nothing 591 */ 592 593 static void 594 bucket_drain(uma_zone_t zone, uma_bucket_t bucket) 595 { 596 void *item; 597 598 if (bucket == NULL) 599 return; 600 601 while (bucket->ub_cnt > 0) { 602 bucket->ub_cnt--; 603 item = bucket->ub_bucket[bucket->ub_cnt]; 604 #ifdef INVARIANTS 605 bucket->ub_bucket[bucket->ub_cnt] = NULL; 606 KASSERT(item != NULL, 607 ("bucket_drain: botched ptr, item is NULL")); 608 #endif 609 zone_free_item(zone, item, NULL, SKIP_DTOR, 0); 610 } 611 } 612 613 /* 614 * Drains the per cpu caches for a zone. 615 * 616 * NOTE: This may only be called while the zone is being turn down, and not 617 * during normal operation. This is necessary in order that we do not have 618 * to migrate CPUs to drain the per-CPU caches. 619 * 620 * Arguments: 621 * zone The zone to drain, must be unlocked. 622 * 623 * Returns: 624 * Nothing 625 */ 626 static void 627 cache_drain(uma_zone_t zone) 628 { 629 uma_cache_t cache; 630 int cpu; 631 632 /* 633 * XXX: It is safe to not lock the per-CPU caches, because we're 634 * tearing down the zone anyway. I.e., there will be no further use 635 * of the caches at this point. 636 * 637 * XXX: It would good to be able to assert that the zone is being 638 * torn down to prevent improper use of cache_drain(). 639 * 640 * XXX: We lock the zone before passing into bucket_cache_drain() as 641 * it is used elsewhere. Should the tear-down path be made special 642 * there in some form? 643 */ 644 CPU_FOREACH(cpu) { 645 cache = &zone->uz_cpu[cpu]; 646 bucket_drain(zone, cache->uc_allocbucket); 647 bucket_drain(zone, cache->uc_freebucket); 648 if (cache->uc_allocbucket != NULL) 649 bucket_free(cache->uc_allocbucket); 650 if (cache->uc_freebucket != NULL) 651 bucket_free(cache->uc_freebucket); 652 cache->uc_allocbucket = cache->uc_freebucket = NULL; 653 } 654 ZONE_LOCK(zone); 655 bucket_cache_drain(zone); 656 ZONE_UNLOCK(zone); 657 } 658 659 /* 660 * Drain the cached buckets from a zone. Expects a locked zone on entry. 661 */ 662 static void 663 bucket_cache_drain(uma_zone_t zone) 664 { 665 uma_bucket_t bucket; 666 667 /* 668 * Drain the bucket queues and free the buckets, we just keep two per 669 * cpu (alloc/free). 670 */ 671 while ((bucket = LIST_FIRST(&zone->uz_full_bucket)) != NULL) { 672 LIST_REMOVE(bucket, ub_link); 673 ZONE_UNLOCK(zone); 674 bucket_drain(zone, bucket); 675 bucket_free(bucket); 676 ZONE_LOCK(zone); 677 } 678 679 /* Now we do the free queue.. */ 680 while ((bucket = LIST_FIRST(&zone->uz_free_bucket)) != NULL) { 681 LIST_REMOVE(bucket, ub_link); 682 bucket_free(bucket); 683 } 684 } 685 686 /* 687 * Frees pages from a keg back to the system. This is done on demand from 688 * the pageout daemon. 689 * 690 * Returns nothing. 691 */ 692 static void 693 keg_drain(uma_keg_t keg) 694 { 695 struct slabhead freeslabs = { 0 }; 696 uma_slab_t slab; 697 uma_slab_t n; 698 u_int8_t flags; 699 u_int8_t *mem; 700 int i; 701 702 /* 703 * We don't want to take pages from statically allocated kegs at this 704 * time 705 */ 706 if (keg->uk_flags & UMA_ZONE_NOFREE || keg->uk_freef == NULL) 707 return; 708 709 #ifdef UMA_DEBUG 710 printf("%s free items: %u\n", keg->uk_name, keg->uk_free); 711 #endif 712 KEG_LOCK(keg); 713 if (keg->uk_free == 0) 714 goto finished; 715 716 slab = LIST_FIRST(&keg->uk_free_slab); 717 while (slab) { 718 n = LIST_NEXT(slab, us_link); 719 720 /* We have no where to free these to */ 721 if (slab->us_flags & UMA_SLAB_BOOT) { 722 slab = n; 723 continue; 724 } 725 726 LIST_REMOVE(slab, us_link); 727 keg->uk_pages -= keg->uk_ppera; 728 keg->uk_free -= keg->uk_ipers; 729 730 if (keg->uk_flags & UMA_ZONE_HASH) 731 UMA_HASH_REMOVE(&keg->uk_hash, slab, slab->us_data); 732 733 SLIST_INSERT_HEAD(&freeslabs, slab, us_hlink); 734 735 slab = n; 736 } 737 finished: 738 KEG_UNLOCK(keg); 739 740 while ((slab = SLIST_FIRST(&freeslabs)) != NULL) { 741 SLIST_REMOVE(&freeslabs, slab, uma_slab, us_hlink); 742 if (keg->uk_fini) 743 for (i = 0; i < keg->uk_ipers; i++) 744 keg->uk_fini( 745 slab->us_data + (keg->uk_rsize * i), 746 keg->uk_size); 747 flags = slab->us_flags; 748 mem = slab->us_data; 749 750 if (keg->uk_flags & UMA_ZONE_VTOSLAB) { 751 vm_object_t obj; 752 753 if (flags & UMA_SLAB_KMEM) 754 obj = kmem_object; 755 else if (flags & UMA_SLAB_KERNEL) 756 obj = kernel_object; 757 else 758 obj = NULL; 759 for (i = 0; i < keg->uk_ppera; i++) 760 vsetobj((vm_offset_t)mem + (i * PAGE_SIZE), 761 obj); 762 } 763 if (keg->uk_flags & UMA_ZONE_OFFPAGE) 764 zone_free_item(keg->uk_slabzone, slab, NULL, 765 SKIP_NONE, ZFREE_STATFREE); 766 #ifdef UMA_DEBUG 767 printf("%s: Returning %d bytes.\n", 768 keg->uk_name, UMA_SLAB_SIZE * keg->uk_ppera); 769 #endif 770 keg->uk_freef(mem, UMA_SLAB_SIZE * keg->uk_ppera, flags); 771 } 772 } 773 774 static void 775 zone_drain_wait(uma_zone_t zone, int waitok) 776 { 777 778 /* 779 * Set draining to interlock with zone_dtor() so we can release our 780 * locks as we go. Only dtor() should do a WAITOK call since it 781 * is the only call that knows the structure will still be available 782 * when it wakes up. 783 */ 784 ZONE_LOCK(zone); 785 while (zone->uz_flags & UMA_ZFLAG_DRAINING) { 786 if (waitok == M_NOWAIT) 787 goto out; 788 mtx_unlock(&uma_mtx); 789 msleep(zone, zone->uz_lock, PVM, "zonedrain", 1); 790 mtx_lock(&uma_mtx); 791 } 792 zone->uz_flags |= UMA_ZFLAG_DRAINING; 793 bucket_cache_drain(zone); 794 ZONE_UNLOCK(zone); 795 /* 796 * The DRAINING flag protects us from being freed while 797 * we're running. Normally the uma_mtx would protect us but we 798 * must be able to release and acquire the right lock for each keg. 799 */ 800 zone_foreach_keg(zone, &keg_drain); 801 ZONE_LOCK(zone); 802 zone->uz_flags &= ~UMA_ZFLAG_DRAINING; 803 wakeup(zone); 804 out: 805 ZONE_UNLOCK(zone); 806 } 807 808 void 809 zone_drain(uma_zone_t zone) 810 { 811 812 zone_drain_wait(zone, M_NOWAIT); 813 } 814 815 /* 816 * Allocate a new slab for a keg. This does not insert the slab onto a list. 817 * 818 * Arguments: 819 * wait Shall we wait? 820 * 821 * Returns: 822 * The slab that was allocated or NULL if there is no memory and the 823 * caller specified M_NOWAIT. 824 */ 825 static uma_slab_t 826 keg_alloc_slab(uma_keg_t keg, uma_zone_t zone, int wait) 827 { 828 uma_slabrefcnt_t slabref; 829 uma_alloc allocf; 830 uma_slab_t slab; 831 u_int8_t *mem; 832 u_int8_t flags; 833 int i; 834 835 mtx_assert(&keg->uk_lock, MA_OWNED); 836 slab = NULL; 837 838 #ifdef UMA_DEBUG 839 printf("slab_zalloc: Allocating a new slab for %s\n", keg->uk_name); 840 #endif 841 allocf = keg->uk_allocf; 842 KEG_UNLOCK(keg); 843 844 if (keg->uk_flags & UMA_ZONE_OFFPAGE) { 845 slab = zone_alloc_item(keg->uk_slabzone, NULL, wait); 846 if (slab == NULL) { 847 KEG_LOCK(keg); 848 return NULL; 849 } 850 } 851 852 /* 853 * This reproduces the old vm_zone behavior of zero filling pages the 854 * first time they are added to a zone. 855 * 856 * Malloced items are zeroed in uma_zalloc. 857 */ 858 859 if ((keg->uk_flags & UMA_ZONE_MALLOC) == 0) 860 wait |= M_ZERO; 861 else 862 wait &= ~M_ZERO; 863 864 if (keg->uk_flags & UMA_ZONE_NODUMP) 865 wait |= M_NODUMP; 866 867 /* zone is passed for legacy reasons. */ 868 mem = allocf(zone, keg->uk_ppera * UMA_SLAB_SIZE, &flags, wait); 869 if (mem == NULL) { 870 if (keg->uk_flags & UMA_ZONE_OFFPAGE) 871 zone_free_item(keg->uk_slabzone, slab, NULL, 872 SKIP_NONE, ZFREE_STATFREE); 873 KEG_LOCK(keg); 874 return (NULL); 875 } 876 877 /* Point the slab into the allocated memory */ 878 if (!(keg->uk_flags & UMA_ZONE_OFFPAGE)) 879 slab = (uma_slab_t )(mem + keg->uk_pgoff); 880 881 if (keg->uk_flags & UMA_ZONE_VTOSLAB) 882 for (i = 0; i < keg->uk_ppera; i++) 883 vsetslab((vm_offset_t)mem + (i * PAGE_SIZE), slab); 884 885 slab->us_keg = keg; 886 slab->us_data = mem; 887 slab->us_freecount = keg->uk_ipers; 888 slab->us_firstfree = 0; 889 slab->us_flags = flags; 890 891 if (keg->uk_flags & UMA_ZONE_REFCNT) { 892 slabref = (uma_slabrefcnt_t)slab; 893 for (i = 0; i < keg->uk_ipers; i++) { 894 slabref->us_freelist[i].us_refcnt = 0; 895 slabref->us_freelist[i].us_item = i+1; 896 } 897 } else { 898 for (i = 0; i < keg->uk_ipers; i++) 899 slab->us_freelist[i].us_item = i+1; 900 } 901 902 if (keg->uk_init != NULL) { 903 for (i = 0; i < keg->uk_ipers; i++) 904 if (keg->uk_init(slab->us_data + (keg->uk_rsize * i), 905 keg->uk_size, wait) != 0) 906 break; 907 if (i != keg->uk_ipers) { 908 if (keg->uk_fini != NULL) { 909 for (i--; i > -1; i--) 910 keg->uk_fini(slab->us_data + 911 (keg->uk_rsize * i), 912 keg->uk_size); 913 } 914 if (keg->uk_flags & UMA_ZONE_VTOSLAB) { 915 vm_object_t obj; 916 917 if (flags & UMA_SLAB_KMEM) 918 obj = kmem_object; 919 else if (flags & UMA_SLAB_KERNEL) 920 obj = kernel_object; 921 else 922 obj = NULL; 923 for (i = 0; i < keg->uk_ppera; i++) 924 vsetobj((vm_offset_t)mem + 925 (i * PAGE_SIZE), obj); 926 } 927 if (keg->uk_flags & UMA_ZONE_OFFPAGE) 928 zone_free_item(keg->uk_slabzone, slab, 929 NULL, SKIP_NONE, ZFREE_STATFREE); 930 keg->uk_freef(mem, UMA_SLAB_SIZE * keg->uk_ppera, 931 flags); 932 KEG_LOCK(keg); 933 return (NULL); 934 } 935 } 936 KEG_LOCK(keg); 937 938 if (keg->uk_flags & UMA_ZONE_HASH) 939 UMA_HASH_INSERT(&keg->uk_hash, slab, mem); 940 941 keg->uk_pages += keg->uk_ppera; 942 keg->uk_free += keg->uk_ipers; 943 944 return (slab); 945 } 946 947 /* 948 * This function is intended to be used early on in place of page_alloc() so 949 * that we may use the boot time page cache to satisfy allocations before 950 * the VM is ready. 951 */ 952 static void * 953 startup_alloc(uma_zone_t zone, int bytes, u_int8_t *pflag, int wait) 954 { 955 uma_keg_t keg; 956 uma_slab_t tmps; 957 int pages, check_pages; 958 959 keg = zone_first_keg(zone); 960 pages = howmany(bytes, PAGE_SIZE); 961 check_pages = pages - 1; 962 KASSERT(pages > 0, ("startup_alloc can't reserve 0 pages\n")); 963 964 /* 965 * Check our small startup cache to see if it has pages remaining. 966 */ 967 mtx_lock(&uma_boot_pages_mtx); 968 969 /* First check if we have enough room. */ 970 tmps = LIST_FIRST(&uma_boot_pages); 971 while (tmps != NULL && check_pages-- > 0) 972 tmps = LIST_NEXT(tmps, us_link); 973 if (tmps != NULL) { 974 /* 975 * It's ok to lose tmps references. The last one will 976 * have tmps->us_data pointing to the start address of 977 * "pages" contiguous pages of memory. 978 */ 979 while (pages-- > 0) { 980 tmps = LIST_FIRST(&uma_boot_pages); 981 LIST_REMOVE(tmps, us_link); 982 } 983 mtx_unlock(&uma_boot_pages_mtx); 984 *pflag = tmps->us_flags; 985 return (tmps->us_data); 986 } 987 mtx_unlock(&uma_boot_pages_mtx); 988 if (booted < UMA_STARTUP2) 989 panic("UMA: Increase vm.boot_pages"); 990 /* 991 * Now that we've booted reset these users to their real allocator. 992 */ 993 #ifdef UMA_MD_SMALL_ALLOC 994 keg->uk_allocf = (keg->uk_ppera > 1) ? page_alloc : uma_small_alloc; 995 #else 996 keg->uk_allocf = page_alloc; 997 #endif 998 return keg->uk_allocf(zone, bytes, pflag, wait); 999 } 1000 1001 /* 1002 * Allocates a number of pages from the system 1003 * 1004 * Arguments: 1005 * bytes The number of bytes requested 1006 * wait Shall we wait? 1007 * 1008 * Returns: 1009 * A pointer to the alloced memory or possibly 1010 * NULL if M_NOWAIT is set. 1011 */ 1012 static void * 1013 page_alloc(uma_zone_t zone, int bytes, u_int8_t *pflag, int wait) 1014 { 1015 void *p; /* Returned page */ 1016 1017 *pflag = UMA_SLAB_KMEM; 1018 p = (void *) kmem_malloc(kmem_map, bytes, wait); 1019 1020 return (p); 1021 } 1022 1023 /* 1024 * Allocates a number of pages from within an object 1025 * 1026 * Arguments: 1027 * bytes The number of bytes requested 1028 * wait Shall we wait? 1029 * 1030 * Returns: 1031 * A pointer to the alloced memory or possibly 1032 * NULL if M_NOWAIT is set. 1033 */ 1034 static void * 1035 noobj_alloc(uma_zone_t zone, int bytes, u_int8_t *flags, int wait) 1036 { 1037 TAILQ_HEAD(, vm_page) alloctail; 1038 u_long npages; 1039 vm_offset_t retkva, zkva; 1040 vm_page_t p, p_next; 1041 uma_keg_t keg; 1042 1043 TAILQ_INIT(&alloctail); 1044 keg = zone_first_keg(zone); 1045 1046 npages = howmany(bytes, PAGE_SIZE); 1047 while (npages > 0) { 1048 p = vm_page_alloc(NULL, 0, VM_ALLOC_INTERRUPT | 1049 VM_ALLOC_WIRED | VM_ALLOC_NOOBJ); 1050 if (p != NULL) { 1051 /* 1052 * Since the page does not belong to an object, its 1053 * listq is unused. 1054 */ 1055 TAILQ_INSERT_TAIL(&alloctail, p, listq); 1056 npages--; 1057 continue; 1058 } 1059 if (wait & M_WAITOK) { 1060 VM_WAIT; 1061 continue; 1062 } 1063 1064 /* 1065 * Page allocation failed, free intermediate pages and 1066 * exit. 1067 */ 1068 TAILQ_FOREACH_SAFE(p, &alloctail, listq, p_next) { 1069 vm_page_unwire(p, 0); 1070 vm_page_free(p); 1071 } 1072 return (NULL); 1073 } 1074 *flags = UMA_SLAB_PRIV; 1075 zkva = keg->uk_kva + 1076 atomic_fetchadd_long(&keg->uk_offset, round_page(bytes)); 1077 retkva = zkva; 1078 TAILQ_FOREACH(p, &alloctail, listq) { 1079 pmap_qenter(zkva, &p, 1); 1080 zkva += PAGE_SIZE; 1081 } 1082 1083 return ((void *)retkva); 1084 } 1085 1086 /* 1087 * Frees a number of pages to the system 1088 * 1089 * Arguments: 1090 * mem A pointer to the memory to be freed 1091 * size The size of the memory being freed 1092 * flags The original p->us_flags field 1093 * 1094 * Returns: 1095 * Nothing 1096 */ 1097 static void 1098 page_free(void *mem, int size, u_int8_t flags) 1099 { 1100 vm_map_t map; 1101 1102 if (flags & UMA_SLAB_KMEM) 1103 map = kmem_map; 1104 else if (flags & UMA_SLAB_KERNEL) 1105 map = kernel_map; 1106 else 1107 panic("UMA: page_free used with invalid flags %d", flags); 1108 1109 kmem_free(map, (vm_offset_t)mem, size); 1110 } 1111 1112 /* 1113 * Zero fill initializer 1114 * 1115 * Arguments/Returns follow uma_init specifications 1116 */ 1117 static int 1118 zero_init(void *mem, int size, int flags) 1119 { 1120 bzero(mem, size); 1121 return (0); 1122 } 1123 1124 /* 1125 * Finish creating a small uma keg. This calculates ipers, and the keg size. 1126 * 1127 * Arguments 1128 * keg The zone we should initialize 1129 * 1130 * Returns 1131 * Nothing 1132 */ 1133 static void 1134 keg_small_init(uma_keg_t keg) 1135 { 1136 u_int rsize; 1137 u_int memused; 1138 u_int wastedspace; 1139 u_int shsize; 1140 1141 KASSERT(keg != NULL, ("Keg is null in keg_small_init")); 1142 rsize = keg->uk_size; 1143 1144 if (rsize < UMA_SMALLEST_UNIT) 1145 rsize = UMA_SMALLEST_UNIT; 1146 if (rsize & keg->uk_align) 1147 rsize = (rsize & ~keg->uk_align) + (keg->uk_align + 1); 1148 1149 keg->uk_rsize = rsize; 1150 keg->uk_ppera = 1; 1151 1152 if (keg->uk_flags & UMA_ZONE_OFFPAGE) { 1153 shsize = 0; 1154 } else if (keg->uk_flags & UMA_ZONE_REFCNT) { 1155 rsize += UMA_FRITMREF_SZ; /* linkage & refcnt */ 1156 shsize = sizeof(struct uma_slab_refcnt); 1157 } else { 1158 rsize += UMA_FRITM_SZ; /* Account for linkage */ 1159 shsize = sizeof(struct uma_slab); 1160 } 1161 1162 keg->uk_ipers = (UMA_SLAB_SIZE - shsize) / rsize; 1163 KASSERT(keg->uk_ipers != 0, ("keg_small_init: ipers is 0")); 1164 memused = keg->uk_ipers * rsize + shsize; 1165 wastedspace = UMA_SLAB_SIZE - memused; 1166 1167 /* 1168 * We can't do OFFPAGE if we're internal or if we've been 1169 * asked to not go to the VM for buckets. If we do this we 1170 * may end up going to the VM (kmem_map) for slabs which we 1171 * do not want to do if we're UMA_ZFLAG_CACHEONLY as a 1172 * result of UMA_ZONE_VM, which clearly forbids it. 1173 */ 1174 if ((keg->uk_flags & UMA_ZFLAG_INTERNAL) || 1175 (keg->uk_flags & UMA_ZFLAG_CACHEONLY)) 1176 return; 1177 1178 if ((wastedspace >= UMA_MAX_WASTE) && 1179 (keg->uk_ipers < (UMA_SLAB_SIZE / keg->uk_rsize))) { 1180 keg->uk_ipers = UMA_SLAB_SIZE / keg->uk_rsize; 1181 KASSERT(keg->uk_ipers <= 255, 1182 ("keg_small_init: keg->uk_ipers too high!")); 1183 #ifdef UMA_DEBUG 1184 printf("UMA decided we need offpage slab headers for " 1185 "keg: %s, calculated wastedspace = %d, " 1186 "maximum wasted space allowed = %d, " 1187 "calculated ipers = %d, " 1188 "new wasted space = %d\n", keg->uk_name, wastedspace, 1189 UMA_MAX_WASTE, keg->uk_ipers, 1190 UMA_SLAB_SIZE - keg->uk_ipers * keg->uk_rsize); 1191 #endif 1192 keg->uk_flags |= UMA_ZONE_OFFPAGE; 1193 if ((keg->uk_flags & UMA_ZONE_VTOSLAB) == 0) 1194 keg->uk_flags |= UMA_ZONE_HASH; 1195 } 1196 } 1197 1198 /* 1199 * Finish creating a large (> UMA_SLAB_SIZE) uma kegs. Just give in and do 1200 * OFFPAGE for now. When I can allow for more dynamic slab sizes this will be 1201 * more complicated. 1202 * 1203 * Arguments 1204 * keg The keg we should initialize 1205 * 1206 * Returns 1207 * Nothing 1208 */ 1209 static void 1210 keg_large_init(uma_keg_t keg) 1211 { 1212 int pages; 1213 1214 KASSERT(keg != NULL, ("Keg is null in keg_large_init")); 1215 KASSERT((keg->uk_flags & UMA_ZFLAG_CACHEONLY) == 0, 1216 ("keg_large_init: Cannot large-init a UMA_ZFLAG_CACHEONLY keg")); 1217 1218 pages = keg->uk_size / UMA_SLAB_SIZE; 1219 1220 /* Account for remainder */ 1221 if ((pages * UMA_SLAB_SIZE) < keg->uk_size) 1222 pages++; 1223 1224 keg->uk_ppera = pages; 1225 keg->uk_ipers = 1; 1226 keg->uk_rsize = keg->uk_size; 1227 1228 /* We can't do OFFPAGE if we're internal, bail out here. */ 1229 if (keg->uk_flags & UMA_ZFLAG_INTERNAL) 1230 return; 1231 1232 keg->uk_flags |= UMA_ZONE_OFFPAGE; 1233 if ((keg->uk_flags & UMA_ZONE_VTOSLAB) == 0) 1234 keg->uk_flags |= UMA_ZONE_HASH; 1235 } 1236 1237 static void 1238 keg_cachespread_init(uma_keg_t keg) 1239 { 1240 int alignsize; 1241 int trailer; 1242 int pages; 1243 int rsize; 1244 1245 alignsize = keg->uk_align + 1; 1246 rsize = keg->uk_size; 1247 /* 1248 * We want one item to start on every align boundary in a page. To 1249 * do this we will span pages. We will also extend the item by the 1250 * size of align if it is an even multiple of align. Otherwise, it 1251 * would fall on the same boundary every time. 1252 */ 1253 if (rsize & keg->uk_align) 1254 rsize = (rsize & ~keg->uk_align) + alignsize; 1255 if ((rsize & alignsize) == 0) 1256 rsize += alignsize; 1257 trailer = rsize - keg->uk_size; 1258 pages = (rsize * (PAGE_SIZE / alignsize)) / PAGE_SIZE; 1259 pages = MIN(pages, (128 * 1024) / PAGE_SIZE); 1260 keg->uk_rsize = rsize; 1261 keg->uk_ppera = pages; 1262 keg->uk_ipers = ((pages * PAGE_SIZE) + trailer) / rsize; 1263 keg->uk_flags |= UMA_ZONE_OFFPAGE | UMA_ZONE_VTOSLAB; 1264 KASSERT(keg->uk_ipers <= uma_max_ipers, 1265 ("%s: keg->uk_ipers too high(%d) increase max_ipers", __func__, 1266 keg->uk_ipers)); 1267 } 1268 1269 /* 1270 * Keg header ctor. This initializes all fields, locks, etc. And inserts 1271 * the keg onto the global keg list. 1272 * 1273 * Arguments/Returns follow uma_ctor specifications 1274 * udata Actually uma_kctor_args 1275 */ 1276 static int 1277 keg_ctor(void *mem, int size, void *udata, int flags) 1278 { 1279 struct uma_kctor_args *arg = udata; 1280 uma_keg_t keg = mem; 1281 uma_zone_t zone; 1282 1283 bzero(keg, size); 1284 keg->uk_size = arg->size; 1285 keg->uk_init = arg->uminit; 1286 keg->uk_fini = arg->fini; 1287 keg->uk_align = arg->align; 1288 keg->uk_free = 0; 1289 keg->uk_pages = 0; 1290 keg->uk_flags = arg->flags; 1291 keg->uk_allocf = page_alloc; 1292 keg->uk_freef = page_free; 1293 keg->uk_recurse = 0; 1294 keg->uk_slabzone = NULL; 1295 1296 /* 1297 * The master zone is passed to us at keg-creation time. 1298 */ 1299 zone = arg->zone; 1300 keg->uk_name = zone->uz_name; 1301 1302 if (arg->flags & UMA_ZONE_VM) 1303 keg->uk_flags |= UMA_ZFLAG_CACHEONLY; 1304 1305 if (arg->flags & UMA_ZONE_ZINIT) 1306 keg->uk_init = zero_init; 1307 1308 if (arg->flags & UMA_ZONE_REFCNT || arg->flags & UMA_ZONE_MALLOC) 1309 keg->uk_flags |= UMA_ZONE_VTOSLAB; 1310 1311 /* 1312 * The +UMA_FRITM_SZ added to uk_size is to account for the 1313 * linkage that is added to the size in keg_small_init(). If 1314 * we don't account for this here then we may end up in 1315 * keg_small_init() with a calculated 'ipers' of 0. 1316 */ 1317 if (keg->uk_flags & UMA_ZONE_REFCNT) { 1318 if (keg->uk_flags & UMA_ZONE_CACHESPREAD) 1319 keg_cachespread_init(keg); 1320 else if ((keg->uk_size+UMA_FRITMREF_SZ) > 1321 (UMA_SLAB_SIZE - sizeof(struct uma_slab_refcnt))) 1322 keg_large_init(keg); 1323 else 1324 keg_small_init(keg); 1325 } else { 1326 if (keg->uk_flags & UMA_ZONE_CACHESPREAD) 1327 keg_cachespread_init(keg); 1328 else if ((keg->uk_size+UMA_FRITM_SZ) > 1329 (UMA_SLAB_SIZE - sizeof(struct uma_slab))) 1330 keg_large_init(keg); 1331 else 1332 keg_small_init(keg); 1333 } 1334 1335 if (keg->uk_flags & UMA_ZONE_OFFPAGE) { 1336 if (keg->uk_flags & UMA_ZONE_REFCNT) 1337 keg->uk_slabzone = slabrefzone; 1338 else 1339 keg->uk_slabzone = slabzone; 1340 } 1341 1342 /* 1343 * If we haven't booted yet we need allocations to go through the 1344 * startup cache until the vm is ready. 1345 */ 1346 if (keg->uk_ppera == 1) { 1347 #ifdef UMA_MD_SMALL_ALLOC 1348 keg->uk_allocf = uma_small_alloc; 1349 keg->uk_freef = uma_small_free; 1350 1351 if (booted < UMA_STARTUP) 1352 keg->uk_allocf = startup_alloc; 1353 #else 1354 if (booted < UMA_STARTUP2) 1355 keg->uk_allocf = startup_alloc; 1356 #endif 1357 } else if (booted < UMA_STARTUP2 && 1358 (keg->uk_flags & UMA_ZFLAG_INTERNAL)) 1359 keg->uk_allocf = startup_alloc; 1360 1361 /* 1362 * Initialize keg's lock (shared among zones). 1363 */ 1364 if (arg->flags & UMA_ZONE_MTXCLASS) 1365 KEG_LOCK_INIT(keg, 1); 1366 else 1367 KEG_LOCK_INIT(keg, 0); 1368 1369 /* 1370 * If we're putting the slab header in the actual page we need to 1371 * figure out where in each page it goes. This calculates a right 1372 * justified offset into the memory on an ALIGN_PTR boundary. 1373 */ 1374 if (!(keg->uk_flags & UMA_ZONE_OFFPAGE)) { 1375 u_int totsize; 1376 1377 /* Size of the slab struct and free list */ 1378 if (keg->uk_flags & UMA_ZONE_REFCNT) 1379 totsize = sizeof(struct uma_slab_refcnt) + 1380 keg->uk_ipers * UMA_FRITMREF_SZ; 1381 else 1382 totsize = sizeof(struct uma_slab) + 1383 keg->uk_ipers * UMA_FRITM_SZ; 1384 1385 if (totsize & UMA_ALIGN_PTR) 1386 totsize = (totsize & ~UMA_ALIGN_PTR) + 1387 (UMA_ALIGN_PTR + 1); 1388 keg->uk_pgoff = (UMA_SLAB_SIZE * keg->uk_ppera) - totsize; 1389 1390 if (keg->uk_flags & UMA_ZONE_REFCNT) 1391 totsize = keg->uk_pgoff + sizeof(struct uma_slab_refcnt) 1392 + keg->uk_ipers * UMA_FRITMREF_SZ; 1393 else 1394 totsize = keg->uk_pgoff + sizeof(struct uma_slab) 1395 + keg->uk_ipers * UMA_FRITM_SZ; 1396 1397 /* 1398 * The only way the following is possible is if with our 1399 * UMA_ALIGN_PTR adjustments we are now bigger than 1400 * UMA_SLAB_SIZE. I haven't checked whether this is 1401 * mathematically possible for all cases, so we make 1402 * sure here anyway. 1403 */ 1404 if (totsize > UMA_SLAB_SIZE * keg->uk_ppera) { 1405 printf("zone %s ipers %d rsize %d size %d\n", 1406 zone->uz_name, keg->uk_ipers, keg->uk_rsize, 1407 keg->uk_size); 1408 panic("UMA slab won't fit."); 1409 } 1410 } 1411 1412 if (keg->uk_flags & UMA_ZONE_HASH) 1413 hash_alloc(&keg->uk_hash); 1414 1415 #ifdef UMA_DEBUG 1416 printf("UMA: %s(%p) size %d(%d) flags %#x ipers %d ppera %d out %d free %d\n", 1417 zone->uz_name, zone, keg->uk_size, keg->uk_rsize, keg->uk_flags, 1418 keg->uk_ipers, keg->uk_ppera, 1419 (keg->uk_ipers * keg->uk_pages) - keg->uk_free, keg->uk_free); 1420 #endif 1421 1422 LIST_INSERT_HEAD(&keg->uk_zones, zone, uz_link); 1423 1424 mtx_lock(&uma_mtx); 1425 LIST_INSERT_HEAD(&uma_kegs, keg, uk_link); 1426 mtx_unlock(&uma_mtx); 1427 return (0); 1428 } 1429 1430 /* 1431 * Zone header ctor. This initializes all fields, locks, etc. 1432 * 1433 * Arguments/Returns follow uma_ctor specifications 1434 * udata Actually uma_zctor_args 1435 */ 1436 static int 1437 zone_ctor(void *mem, int size, void *udata, int flags) 1438 { 1439 struct uma_zctor_args *arg = udata; 1440 uma_zone_t zone = mem; 1441 uma_zone_t z; 1442 uma_keg_t keg; 1443 1444 bzero(zone, size); 1445 zone->uz_name = arg->name; 1446 zone->uz_ctor = arg->ctor; 1447 zone->uz_dtor = arg->dtor; 1448 zone->uz_slab = zone_fetch_slab; 1449 zone->uz_init = NULL; 1450 zone->uz_fini = NULL; 1451 zone->uz_allocs = 0; 1452 zone->uz_frees = 0; 1453 zone->uz_fails = 0; 1454 zone->uz_sleeps = 0; 1455 zone->uz_fills = zone->uz_count = 0; 1456 zone->uz_flags = 0; 1457 zone->uz_warning = NULL; 1458 timevalclear(&zone->uz_ratecheck); 1459 keg = arg->keg; 1460 1461 if (arg->flags & UMA_ZONE_SECONDARY) { 1462 KASSERT(arg->keg != NULL, ("Secondary zone on zero'd keg")); 1463 zone->uz_init = arg->uminit; 1464 zone->uz_fini = arg->fini; 1465 zone->uz_lock = &keg->uk_lock; 1466 zone->uz_flags |= UMA_ZONE_SECONDARY; 1467 mtx_lock(&uma_mtx); 1468 ZONE_LOCK(zone); 1469 LIST_FOREACH(z, &keg->uk_zones, uz_link) { 1470 if (LIST_NEXT(z, uz_link) == NULL) { 1471 LIST_INSERT_AFTER(z, zone, uz_link); 1472 break; 1473 } 1474 } 1475 ZONE_UNLOCK(zone); 1476 mtx_unlock(&uma_mtx); 1477 } else if (keg == NULL) { 1478 if ((keg = uma_kcreate(zone, arg->size, arg->uminit, arg->fini, 1479 arg->align, arg->flags)) == NULL) 1480 return (ENOMEM); 1481 } else { 1482 struct uma_kctor_args karg; 1483 int error; 1484 1485 /* We should only be here from uma_startup() */ 1486 karg.size = arg->size; 1487 karg.uminit = arg->uminit; 1488 karg.fini = arg->fini; 1489 karg.align = arg->align; 1490 karg.flags = arg->flags; 1491 karg.zone = zone; 1492 error = keg_ctor(arg->keg, sizeof(struct uma_keg), &karg, 1493 flags); 1494 if (error) 1495 return (error); 1496 } 1497 /* 1498 * Link in the first keg. 1499 */ 1500 zone->uz_klink.kl_keg = keg; 1501 LIST_INSERT_HEAD(&zone->uz_kegs, &zone->uz_klink, kl_link); 1502 zone->uz_lock = &keg->uk_lock; 1503 zone->uz_size = keg->uk_size; 1504 zone->uz_flags |= (keg->uk_flags & 1505 (UMA_ZONE_INHERIT | UMA_ZFLAG_INHERIT)); 1506 1507 /* 1508 * Some internal zones don't have room allocated for the per cpu 1509 * caches. If we're internal, bail out here. 1510 */ 1511 if (keg->uk_flags & UMA_ZFLAG_INTERNAL) { 1512 KASSERT((zone->uz_flags & UMA_ZONE_SECONDARY) == 0, 1513 ("Secondary zone requested UMA_ZFLAG_INTERNAL")); 1514 return (0); 1515 } 1516 1517 if (keg->uk_flags & UMA_ZONE_MAXBUCKET) 1518 zone->uz_count = BUCKET_MAX; 1519 else if (keg->uk_ipers <= BUCKET_MAX) 1520 zone->uz_count = keg->uk_ipers; 1521 else 1522 zone->uz_count = BUCKET_MAX; 1523 return (0); 1524 } 1525 1526 /* 1527 * Keg header dtor. This frees all data, destroys locks, frees the hash 1528 * table and removes the keg from the global list. 1529 * 1530 * Arguments/Returns follow uma_dtor specifications 1531 * udata unused 1532 */ 1533 static void 1534 keg_dtor(void *arg, int size, void *udata) 1535 { 1536 uma_keg_t keg; 1537 1538 keg = (uma_keg_t)arg; 1539 KEG_LOCK(keg); 1540 if (keg->uk_free != 0) { 1541 printf("Freed UMA keg was not empty (%d items). " 1542 " Lost %d pages of memory.\n", 1543 keg->uk_free, keg->uk_pages); 1544 } 1545 KEG_UNLOCK(keg); 1546 1547 hash_free(&keg->uk_hash); 1548 1549 KEG_LOCK_FINI(keg); 1550 } 1551 1552 /* 1553 * Zone header dtor. 1554 * 1555 * Arguments/Returns follow uma_dtor specifications 1556 * udata unused 1557 */ 1558 static void 1559 zone_dtor(void *arg, int size, void *udata) 1560 { 1561 uma_klink_t klink; 1562 uma_zone_t zone; 1563 uma_keg_t keg; 1564 1565 zone = (uma_zone_t)arg; 1566 keg = zone_first_keg(zone); 1567 1568 if (!(zone->uz_flags & UMA_ZFLAG_INTERNAL)) 1569 cache_drain(zone); 1570 1571 mtx_lock(&uma_mtx); 1572 LIST_REMOVE(zone, uz_link); 1573 mtx_unlock(&uma_mtx); 1574 /* 1575 * XXX there are some races here where 1576 * the zone can be drained but zone lock 1577 * released and then refilled before we 1578 * remove it... we dont care for now 1579 */ 1580 zone_drain_wait(zone, M_WAITOK); 1581 /* 1582 * Unlink all of our kegs. 1583 */ 1584 while ((klink = LIST_FIRST(&zone->uz_kegs)) != NULL) { 1585 klink->kl_keg = NULL; 1586 LIST_REMOVE(klink, kl_link); 1587 if (klink == &zone->uz_klink) 1588 continue; 1589 free(klink, M_TEMP); 1590 } 1591 /* 1592 * We only destroy kegs from non secondary zones. 1593 */ 1594 if ((zone->uz_flags & UMA_ZONE_SECONDARY) == 0) { 1595 mtx_lock(&uma_mtx); 1596 LIST_REMOVE(keg, uk_link); 1597 mtx_unlock(&uma_mtx); 1598 zone_free_item(kegs, keg, NULL, SKIP_NONE, 1599 ZFREE_STATFREE); 1600 } 1601 } 1602 1603 /* 1604 * Traverses every zone in the system and calls a callback 1605 * 1606 * Arguments: 1607 * zfunc A pointer to a function which accepts a zone 1608 * as an argument. 1609 * 1610 * Returns: 1611 * Nothing 1612 */ 1613 static void 1614 zone_foreach(void (*zfunc)(uma_zone_t)) 1615 { 1616 uma_keg_t keg; 1617 uma_zone_t zone; 1618 1619 mtx_lock(&uma_mtx); 1620 LIST_FOREACH(keg, &uma_kegs, uk_link) { 1621 LIST_FOREACH(zone, &keg->uk_zones, uz_link) 1622 zfunc(zone); 1623 } 1624 mtx_unlock(&uma_mtx); 1625 } 1626 1627 /* Public functions */ 1628 /* See uma.h */ 1629 void 1630 uma_startup(void *bootmem, int boot_pages) 1631 { 1632 struct uma_zctor_args args; 1633 uma_slab_t slab; 1634 u_int slabsize; 1635 u_int objsize, totsize, wsize; 1636 int i; 1637 1638 #ifdef UMA_DEBUG 1639 printf("Creating uma keg headers zone and keg.\n"); 1640 #endif 1641 mtx_init(&uma_mtx, "UMA lock", NULL, MTX_DEF); 1642 1643 /* 1644 * Figure out the maximum number of items-per-slab we'll have if 1645 * we're using the OFFPAGE slab header to track free items, given 1646 * all possible object sizes and the maximum desired wastage 1647 * (UMA_MAX_WASTE). 1648 * 1649 * We iterate until we find an object size for 1650 * which the calculated wastage in keg_small_init() will be 1651 * enough to warrant OFFPAGE. Since wastedspace versus objsize 1652 * is an overall increasing see-saw function, we find the smallest 1653 * objsize such that the wastage is always acceptable for objects 1654 * with that objsize or smaller. Since a smaller objsize always 1655 * generates a larger possible uma_max_ipers, we use this computed 1656 * objsize to calculate the largest ipers possible. Since the 1657 * ipers calculated for OFFPAGE slab headers is always larger than 1658 * the ipers initially calculated in keg_small_init(), we use 1659 * the former's equation (UMA_SLAB_SIZE / keg->uk_rsize) to 1660 * obtain the maximum ipers possible for offpage slab headers. 1661 * 1662 * It should be noted that ipers versus objsize is an inversly 1663 * proportional function which drops off rather quickly so as 1664 * long as our UMA_MAX_WASTE is such that the objsize we calculate 1665 * falls into the portion of the inverse relation AFTER the steep 1666 * falloff, then uma_max_ipers shouldn't be too high (~10 on i386). 1667 * 1668 * Note that we have 8-bits (1 byte) to use as a freelist index 1669 * inside the actual slab header itself and this is enough to 1670 * accomodate us. In the worst case, a UMA_SMALLEST_UNIT sized 1671 * object with offpage slab header would have ipers = 1672 * UMA_SLAB_SIZE / UMA_SMALLEST_UNIT (currently = 256), which is 1673 * 1 greater than what our byte-integer freelist index can 1674 * accomodate, but we know that this situation never occurs as 1675 * for UMA_SMALLEST_UNIT-sized objects, we will never calculate 1676 * that we need to go to offpage slab headers. Or, if we do, 1677 * then we trap that condition below and panic in the INVARIANTS case. 1678 */ 1679 wsize = UMA_SLAB_SIZE - sizeof(struct uma_slab) - UMA_MAX_WASTE; 1680 totsize = wsize; 1681 objsize = UMA_SMALLEST_UNIT; 1682 while (totsize >= wsize) { 1683 totsize = (UMA_SLAB_SIZE - sizeof(struct uma_slab)) / 1684 (objsize + UMA_FRITM_SZ); 1685 totsize *= (UMA_FRITM_SZ + objsize); 1686 objsize++; 1687 } 1688 if (objsize > UMA_SMALLEST_UNIT) 1689 objsize--; 1690 uma_max_ipers = MAX(UMA_SLAB_SIZE / objsize, 64); 1691 1692 wsize = UMA_SLAB_SIZE - sizeof(struct uma_slab_refcnt) - UMA_MAX_WASTE; 1693 totsize = wsize; 1694 objsize = UMA_SMALLEST_UNIT; 1695 while (totsize >= wsize) { 1696 totsize = (UMA_SLAB_SIZE - sizeof(struct uma_slab_refcnt)) / 1697 (objsize + UMA_FRITMREF_SZ); 1698 totsize *= (UMA_FRITMREF_SZ + objsize); 1699 objsize++; 1700 } 1701 if (objsize > UMA_SMALLEST_UNIT) 1702 objsize--; 1703 uma_max_ipers_ref = MAX(UMA_SLAB_SIZE / objsize, 64); 1704 1705 KASSERT((uma_max_ipers_ref <= 255) && (uma_max_ipers <= 255), 1706 ("uma_startup: calculated uma_max_ipers values too large!")); 1707 1708 #ifdef UMA_DEBUG 1709 printf("Calculated uma_max_ipers (for OFFPAGE) is %d\n", uma_max_ipers); 1710 printf("Calculated uma_max_ipers_ref (for OFFPAGE) is %d\n", 1711 uma_max_ipers_ref); 1712 #endif 1713 1714 /* "manually" create the initial zone */ 1715 args.name = "UMA Kegs"; 1716 args.size = sizeof(struct uma_keg); 1717 args.ctor = keg_ctor; 1718 args.dtor = keg_dtor; 1719 args.uminit = zero_init; 1720 args.fini = NULL; 1721 args.keg = &masterkeg; 1722 args.align = 32 - 1; 1723 args.flags = UMA_ZFLAG_INTERNAL; 1724 /* The initial zone has no Per cpu queues so it's smaller */ 1725 zone_ctor(kegs, sizeof(struct uma_zone), &args, M_WAITOK); 1726 1727 #ifdef UMA_DEBUG 1728 printf("Filling boot free list.\n"); 1729 #endif 1730 for (i = 0; i < boot_pages; i++) { 1731 slab = (uma_slab_t)((u_int8_t *)bootmem + (i * UMA_SLAB_SIZE)); 1732 slab->us_data = (u_int8_t *)slab; 1733 slab->us_flags = UMA_SLAB_BOOT; 1734 LIST_INSERT_HEAD(&uma_boot_pages, slab, us_link); 1735 } 1736 mtx_init(&uma_boot_pages_mtx, "UMA boot pages", NULL, MTX_DEF); 1737 1738 #ifdef UMA_DEBUG 1739 printf("Creating uma zone headers zone and keg.\n"); 1740 #endif 1741 args.name = "UMA Zones"; 1742 args.size = sizeof(struct uma_zone) + 1743 (sizeof(struct uma_cache) * (mp_maxid + 1)); 1744 args.ctor = zone_ctor; 1745 args.dtor = zone_dtor; 1746 args.uminit = zero_init; 1747 args.fini = NULL; 1748 args.keg = NULL; 1749 args.align = 32 - 1; 1750 args.flags = UMA_ZFLAG_INTERNAL; 1751 /* The initial zone has no Per cpu queues so it's smaller */ 1752 zone_ctor(zones, sizeof(struct uma_zone), &args, M_WAITOK); 1753 1754 #ifdef UMA_DEBUG 1755 printf("Initializing pcpu cache locks.\n"); 1756 #endif 1757 #ifdef UMA_DEBUG 1758 printf("Creating slab and hash zones.\n"); 1759 #endif 1760 1761 /* 1762 * This is the max number of free list items we'll have with 1763 * offpage slabs. 1764 */ 1765 slabsize = uma_max_ipers * UMA_FRITM_SZ; 1766 slabsize += sizeof(struct uma_slab); 1767 1768 /* Now make a zone for slab headers */ 1769 slabzone = uma_zcreate("UMA Slabs", 1770 slabsize, 1771 NULL, NULL, NULL, NULL, 1772 UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL); 1773 1774 /* 1775 * We also create a zone for the bigger slabs with reference 1776 * counts in them, to accomodate UMA_ZONE_REFCNT zones. 1777 */ 1778 slabsize = uma_max_ipers_ref * UMA_FRITMREF_SZ; 1779 slabsize += sizeof(struct uma_slab_refcnt); 1780 slabrefzone = uma_zcreate("UMA RCntSlabs", 1781 slabsize, 1782 NULL, NULL, NULL, NULL, 1783 UMA_ALIGN_PTR, 1784 UMA_ZFLAG_INTERNAL); 1785 1786 hashzone = uma_zcreate("UMA Hash", 1787 sizeof(struct slabhead *) * UMA_HASH_SIZE_INIT, 1788 NULL, NULL, NULL, NULL, 1789 UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL); 1790 1791 bucket_init(); 1792 1793 booted = UMA_STARTUP; 1794 1795 #ifdef UMA_DEBUG 1796 printf("UMA startup complete.\n"); 1797 #endif 1798 } 1799 1800 /* see uma.h */ 1801 void 1802 uma_startup2(void) 1803 { 1804 booted = UMA_STARTUP2; 1805 bucket_enable(); 1806 #ifdef UMA_DEBUG 1807 printf("UMA startup2 complete.\n"); 1808 #endif 1809 } 1810 1811 /* 1812 * Initialize our callout handle 1813 * 1814 */ 1815 1816 static void 1817 uma_startup3(void) 1818 { 1819 #ifdef UMA_DEBUG 1820 printf("Starting callout.\n"); 1821 #endif 1822 callout_init(&uma_callout, CALLOUT_MPSAFE); 1823 callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL); 1824 #ifdef UMA_DEBUG 1825 printf("UMA startup3 complete.\n"); 1826 #endif 1827 } 1828 1829 static uma_keg_t 1830 uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit, uma_fini fini, 1831 int align, u_int32_t flags) 1832 { 1833 struct uma_kctor_args args; 1834 1835 args.size = size; 1836 args.uminit = uminit; 1837 args.fini = fini; 1838 args.align = (align == UMA_ALIGN_CACHE) ? uma_align_cache : align; 1839 args.flags = flags; 1840 args.zone = zone; 1841 return (zone_alloc_item(kegs, &args, M_WAITOK)); 1842 } 1843 1844 /* See uma.h */ 1845 void 1846 uma_set_align(int align) 1847 { 1848 1849 if (align != UMA_ALIGN_CACHE) 1850 uma_align_cache = align; 1851 } 1852 1853 /* See uma.h */ 1854 uma_zone_t 1855 uma_zcreate(const char *name, size_t size, uma_ctor ctor, uma_dtor dtor, 1856 uma_init uminit, uma_fini fini, int align, u_int32_t flags) 1857 1858 { 1859 struct uma_zctor_args args; 1860 1861 /* This stuff is essential for the zone ctor */ 1862 args.name = name; 1863 args.size = size; 1864 args.ctor = ctor; 1865 args.dtor = dtor; 1866 args.uminit = uminit; 1867 args.fini = fini; 1868 args.align = align; 1869 args.flags = flags; 1870 args.keg = NULL; 1871 1872 return (zone_alloc_item(zones, &args, M_WAITOK)); 1873 } 1874 1875 /* See uma.h */ 1876 uma_zone_t 1877 uma_zsecond_create(char *name, uma_ctor ctor, uma_dtor dtor, 1878 uma_init zinit, uma_fini zfini, uma_zone_t master) 1879 { 1880 struct uma_zctor_args args; 1881 uma_keg_t keg; 1882 1883 keg = zone_first_keg(master); 1884 args.name = name; 1885 args.size = keg->uk_size; 1886 args.ctor = ctor; 1887 args.dtor = dtor; 1888 args.uminit = zinit; 1889 args.fini = zfini; 1890 args.align = keg->uk_align; 1891 args.flags = keg->uk_flags | UMA_ZONE_SECONDARY; 1892 args.keg = keg; 1893 1894 /* XXX Attaches only one keg of potentially many. */ 1895 return (zone_alloc_item(zones, &args, M_WAITOK)); 1896 } 1897 1898 static void 1899 zone_lock_pair(uma_zone_t a, uma_zone_t b) 1900 { 1901 if (a < b) { 1902 ZONE_LOCK(a); 1903 mtx_lock_flags(b->uz_lock, MTX_DUPOK); 1904 } else { 1905 ZONE_LOCK(b); 1906 mtx_lock_flags(a->uz_lock, MTX_DUPOK); 1907 } 1908 } 1909 1910 static void 1911 zone_unlock_pair(uma_zone_t a, uma_zone_t b) 1912 { 1913 1914 ZONE_UNLOCK(a); 1915 ZONE_UNLOCK(b); 1916 } 1917 1918 int 1919 uma_zsecond_add(uma_zone_t zone, uma_zone_t master) 1920 { 1921 uma_klink_t klink; 1922 uma_klink_t kl; 1923 int error; 1924 1925 error = 0; 1926 klink = malloc(sizeof(*klink), M_TEMP, M_WAITOK | M_ZERO); 1927 1928 zone_lock_pair(zone, master); 1929 /* 1930 * zone must use vtoslab() to resolve objects and must already be 1931 * a secondary. 1932 */ 1933 if ((zone->uz_flags & (UMA_ZONE_VTOSLAB | UMA_ZONE_SECONDARY)) 1934 != (UMA_ZONE_VTOSLAB | UMA_ZONE_SECONDARY)) { 1935 error = EINVAL; 1936 goto out; 1937 } 1938 /* 1939 * The new master must also use vtoslab(). 1940 */ 1941 if ((zone->uz_flags & UMA_ZONE_VTOSLAB) != UMA_ZONE_VTOSLAB) { 1942 error = EINVAL; 1943 goto out; 1944 } 1945 /* 1946 * Both must either be refcnt, or not be refcnt. 1947 */ 1948 if ((zone->uz_flags & UMA_ZONE_REFCNT) != 1949 (master->uz_flags & UMA_ZONE_REFCNT)) { 1950 error = EINVAL; 1951 goto out; 1952 } 1953 /* 1954 * The underlying object must be the same size. rsize 1955 * may be different. 1956 */ 1957 if (master->uz_size != zone->uz_size) { 1958 error = E2BIG; 1959 goto out; 1960 } 1961 /* 1962 * Put it at the end of the list. 1963 */ 1964 klink->kl_keg = zone_first_keg(master); 1965 LIST_FOREACH(kl, &zone->uz_kegs, kl_link) { 1966 if (LIST_NEXT(kl, kl_link) == NULL) { 1967 LIST_INSERT_AFTER(kl, klink, kl_link); 1968 break; 1969 } 1970 } 1971 klink = NULL; 1972 zone->uz_flags |= UMA_ZFLAG_MULTI; 1973 zone->uz_slab = zone_fetch_slab_multi; 1974 1975 out: 1976 zone_unlock_pair(zone, master); 1977 if (klink != NULL) 1978 free(klink, M_TEMP); 1979 1980 return (error); 1981 } 1982 1983 1984 /* See uma.h */ 1985 void 1986 uma_zdestroy(uma_zone_t zone) 1987 { 1988 1989 zone_free_item(zones, zone, NULL, SKIP_NONE, ZFREE_STATFREE); 1990 } 1991 1992 /* See uma.h */ 1993 void * 1994 uma_zalloc_arg(uma_zone_t zone, void *udata, int flags) 1995 { 1996 void *item; 1997 uma_cache_t cache; 1998 uma_bucket_t bucket; 1999 int cpu; 2000 2001 /* This is the fast path allocation */ 2002 #ifdef UMA_DEBUG_ALLOC_1 2003 printf("Allocating one item from %s(%p)\n", zone->uz_name, zone); 2004 #endif 2005 CTR3(KTR_UMA, "uma_zalloc_arg thread %x zone %s flags %d", curthread, 2006 zone->uz_name, flags); 2007 2008 if (flags & M_WAITOK) { 2009 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, 2010 "uma_zalloc_arg: zone \"%s\"", zone->uz_name); 2011 } 2012 #ifdef DEBUG_MEMGUARD 2013 if (memguard_cmp_zone(zone)) { 2014 item = memguard_alloc(zone->uz_size, flags); 2015 if (item != NULL) { 2016 /* 2017 * Avoid conflict with the use-after-free 2018 * protecting infrastructure from INVARIANTS. 2019 */ 2020 if (zone->uz_init != NULL && 2021 zone->uz_init != mtrash_init && 2022 zone->uz_init(item, zone->uz_size, flags) != 0) 2023 return (NULL); 2024 if (zone->uz_ctor != NULL && 2025 zone->uz_ctor != mtrash_ctor && 2026 zone->uz_ctor(item, zone->uz_size, udata, flags) != 0) { 2027 zone->uz_fini(item, zone->uz_size); 2028 return (NULL); 2029 } 2030 return (item); 2031 } 2032 /* This is unfortunate but should not be fatal. */ 2033 } 2034 #endif 2035 /* 2036 * If possible, allocate from the per-CPU cache. There are two 2037 * requirements for safe access to the per-CPU cache: (1) the thread 2038 * accessing the cache must not be preempted or yield during access, 2039 * and (2) the thread must not migrate CPUs without switching which 2040 * cache it accesses. We rely on a critical section to prevent 2041 * preemption and migration. We release the critical section in 2042 * order to acquire the zone mutex if we are unable to allocate from 2043 * the current cache; when we re-acquire the critical section, we 2044 * must detect and handle migration if it has occurred. 2045 */ 2046 zalloc_restart: 2047 critical_enter(); 2048 cpu = curcpu; 2049 cache = &zone->uz_cpu[cpu]; 2050 2051 zalloc_start: 2052 bucket = cache->uc_allocbucket; 2053 2054 if (bucket) { 2055 if (bucket->ub_cnt > 0) { 2056 bucket->ub_cnt--; 2057 item = bucket->ub_bucket[bucket->ub_cnt]; 2058 #ifdef INVARIANTS 2059 bucket->ub_bucket[bucket->ub_cnt] = NULL; 2060 #endif 2061 KASSERT(item != NULL, 2062 ("uma_zalloc: Bucket pointer mangled.")); 2063 cache->uc_allocs++; 2064 critical_exit(); 2065 #ifdef INVARIANTS 2066 ZONE_LOCK(zone); 2067 uma_dbg_alloc(zone, NULL, item); 2068 ZONE_UNLOCK(zone); 2069 #endif 2070 if (zone->uz_ctor != NULL) { 2071 if (zone->uz_ctor(item, zone->uz_size, 2072 udata, flags) != 0) { 2073 zone_free_item(zone, item, udata, 2074 SKIP_DTOR, ZFREE_STATFAIL | 2075 ZFREE_STATFREE); 2076 return (NULL); 2077 } 2078 } 2079 if (flags & M_ZERO) 2080 bzero(item, zone->uz_size); 2081 return (item); 2082 } else if (cache->uc_freebucket) { 2083 /* 2084 * We have run out of items in our allocbucket. 2085 * See if we can switch with our free bucket. 2086 */ 2087 if (cache->uc_freebucket->ub_cnt > 0) { 2088 #ifdef UMA_DEBUG_ALLOC 2089 printf("uma_zalloc: Swapping empty with" 2090 " alloc.\n"); 2091 #endif 2092 bucket = cache->uc_freebucket; 2093 cache->uc_freebucket = cache->uc_allocbucket; 2094 cache->uc_allocbucket = bucket; 2095 2096 goto zalloc_start; 2097 } 2098 } 2099 } 2100 /* 2101 * Attempt to retrieve the item from the per-CPU cache has failed, so 2102 * we must go back to the zone. This requires the zone lock, so we 2103 * must drop the critical section, then re-acquire it when we go back 2104 * to the cache. Since the critical section is released, we may be 2105 * preempted or migrate. As such, make sure not to maintain any 2106 * thread-local state specific to the cache from prior to releasing 2107 * the critical section. 2108 */ 2109 critical_exit(); 2110 ZONE_LOCK(zone); 2111 critical_enter(); 2112 cpu = curcpu; 2113 cache = &zone->uz_cpu[cpu]; 2114 bucket = cache->uc_allocbucket; 2115 if (bucket != NULL) { 2116 if (bucket->ub_cnt > 0) { 2117 ZONE_UNLOCK(zone); 2118 goto zalloc_start; 2119 } 2120 bucket = cache->uc_freebucket; 2121 if (bucket != NULL && bucket->ub_cnt > 0) { 2122 ZONE_UNLOCK(zone); 2123 goto zalloc_start; 2124 } 2125 } 2126 2127 /* Since we have locked the zone we may as well send back our stats */ 2128 zone->uz_allocs += cache->uc_allocs; 2129 cache->uc_allocs = 0; 2130 zone->uz_frees += cache->uc_frees; 2131 cache->uc_frees = 0; 2132 2133 /* Our old one is now a free bucket */ 2134 if (cache->uc_allocbucket) { 2135 KASSERT(cache->uc_allocbucket->ub_cnt == 0, 2136 ("uma_zalloc_arg: Freeing a non free bucket.")); 2137 LIST_INSERT_HEAD(&zone->uz_free_bucket, 2138 cache->uc_allocbucket, ub_link); 2139 cache->uc_allocbucket = NULL; 2140 } 2141 2142 /* Check the free list for a new alloc bucket */ 2143 if ((bucket = LIST_FIRST(&zone->uz_full_bucket)) != NULL) { 2144 KASSERT(bucket->ub_cnt != 0, 2145 ("uma_zalloc_arg: Returning an empty bucket.")); 2146 2147 LIST_REMOVE(bucket, ub_link); 2148 cache->uc_allocbucket = bucket; 2149 ZONE_UNLOCK(zone); 2150 goto zalloc_start; 2151 } 2152 /* We are no longer associated with this CPU. */ 2153 critical_exit(); 2154 2155 /* Bump up our uz_count so we get here less */ 2156 if (zone->uz_count < BUCKET_MAX) 2157 zone->uz_count++; 2158 2159 /* 2160 * Now lets just fill a bucket and put it on the free list. If that 2161 * works we'll restart the allocation from the begining. 2162 */ 2163 if (zone_alloc_bucket(zone, flags)) { 2164 ZONE_UNLOCK(zone); 2165 goto zalloc_restart; 2166 } 2167 ZONE_UNLOCK(zone); 2168 /* 2169 * We may not be able to get a bucket so return an actual item. 2170 */ 2171 #ifdef UMA_DEBUG 2172 printf("uma_zalloc_arg: Bucketzone returned NULL\n"); 2173 #endif 2174 2175 item = zone_alloc_item(zone, udata, flags); 2176 return (item); 2177 } 2178 2179 static uma_slab_t 2180 keg_fetch_slab(uma_keg_t keg, uma_zone_t zone, int flags) 2181 { 2182 uma_slab_t slab; 2183 2184 mtx_assert(&keg->uk_lock, MA_OWNED); 2185 slab = NULL; 2186 2187 for (;;) { 2188 /* 2189 * Find a slab with some space. Prefer slabs that are partially 2190 * used over those that are totally full. This helps to reduce 2191 * fragmentation. 2192 */ 2193 if (keg->uk_free != 0) { 2194 if (!LIST_EMPTY(&keg->uk_part_slab)) { 2195 slab = LIST_FIRST(&keg->uk_part_slab); 2196 } else { 2197 slab = LIST_FIRST(&keg->uk_free_slab); 2198 LIST_REMOVE(slab, us_link); 2199 LIST_INSERT_HEAD(&keg->uk_part_slab, slab, 2200 us_link); 2201 } 2202 MPASS(slab->us_keg == keg); 2203 return (slab); 2204 } 2205 2206 /* 2207 * M_NOVM means don't ask at all! 2208 */ 2209 if (flags & M_NOVM) 2210 break; 2211 2212 if (keg->uk_maxpages && keg->uk_pages >= keg->uk_maxpages) { 2213 keg->uk_flags |= UMA_ZFLAG_FULL; 2214 /* 2215 * If this is not a multi-zone, set the FULL bit. 2216 * Otherwise slab_multi() takes care of it. 2217 */ 2218 if ((zone->uz_flags & UMA_ZFLAG_MULTI) == 0) { 2219 zone->uz_flags |= UMA_ZFLAG_FULL; 2220 zone_log_warning(zone); 2221 } 2222 if (flags & M_NOWAIT) 2223 break; 2224 zone->uz_sleeps++; 2225 msleep(keg, &keg->uk_lock, PVM, "keglimit", 0); 2226 continue; 2227 } 2228 keg->uk_recurse++; 2229 slab = keg_alloc_slab(keg, zone, flags); 2230 keg->uk_recurse--; 2231 /* 2232 * If we got a slab here it's safe to mark it partially used 2233 * and return. We assume that the caller is going to remove 2234 * at least one item. 2235 */ 2236 if (slab) { 2237 MPASS(slab->us_keg == keg); 2238 LIST_INSERT_HEAD(&keg->uk_part_slab, slab, us_link); 2239 return (slab); 2240 } 2241 /* 2242 * We might not have been able to get a slab but another cpu 2243 * could have while we were unlocked. Check again before we 2244 * fail. 2245 */ 2246 flags |= M_NOVM; 2247 } 2248 return (slab); 2249 } 2250 2251 static inline void 2252 zone_relock(uma_zone_t zone, uma_keg_t keg) 2253 { 2254 if (zone->uz_lock != &keg->uk_lock) { 2255 KEG_UNLOCK(keg); 2256 ZONE_LOCK(zone); 2257 } 2258 } 2259 2260 static inline void 2261 keg_relock(uma_keg_t keg, uma_zone_t zone) 2262 { 2263 if (zone->uz_lock != &keg->uk_lock) { 2264 ZONE_UNLOCK(zone); 2265 KEG_LOCK(keg); 2266 } 2267 } 2268 2269 static uma_slab_t 2270 zone_fetch_slab(uma_zone_t zone, uma_keg_t keg, int flags) 2271 { 2272 uma_slab_t slab; 2273 2274 if (keg == NULL) 2275 keg = zone_first_keg(zone); 2276 /* 2277 * This is to prevent us from recursively trying to allocate 2278 * buckets. The problem is that if an allocation forces us to 2279 * grab a new bucket we will call page_alloc, which will go off 2280 * and cause the vm to allocate vm_map_entries. If we need new 2281 * buckets there too we will recurse in kmem_alloc and bad 2282 * things happen. So instead we return a NULL bucket, and make 2283 * the code that allocates buckets smart enough to deal with it 2284 */ 2285 if (keg->uk_flags & UMA_ZFLAG_BUCKET && keg->uk_recurse != 0) 2286 return (NULL); 2287 2288 for (;;) { 2289 slab = keg_fetch_slab(keg, zone, flags); 2290 if (slab) 2291 return (slab); 2292 if (flags & (M_NOWAIT | M_NOVM)) 2293 break; 2294 } 2295 return (NULL); 2296 } 2297 2298 /* 2299 * uma_zone_fetch_slab_multi: Fetches a slab from one available keg. Returns 2300 * with the keg locked. Caller must call zone_relock() afterwards if the 2301 * zone lock is required. On NULL the zone lock is held. 2302 * 2303 * The last pointer is used to seed the search. It is not required. 2304 */ 2305 static uma_slab_t 2306 zone_fetch_slab_multi(uma_zone_t zone, uma_keg_t last, int rflags) 2307 { 2308 uma_klink_t klink; 2309 uma_slab_t slab; 2310 uma_keg_t keg; 2311 int flags; 2312 int empty; 2313 int full; 2314 2315 /* 2316 * Don't wait on the first pass. This will skip limit tests 2317 * as well. We don't want to block if we can find a provider 2318 * without blocking. 2319 */ 2320 flags = (rflags & ~M_WAITOK) | M_NOWAIT; 2321 /* 2322 * Use the last slab allocated as a hint for where to start 2323 * the search. 2324 */ 2325 if (last) { 2326 slab = keg_fetch_slab(last, zone, flags); 2327 if (slab) 2328 return (slab); 2329 zone_relock(zone, last); 2330 last = NULL; 2331 } 2332 /* 2333 * Loop until we have a slab incase of transient failures 2334 * while M_WAITOK is specified. I'm not sure this is 100% 2335 * required but we've done it for so long now. 2336 */ 2337 for (;;) { 2338 empty = 0; 2339 full = 0; 2340 /* 2341 * Search the available kegs for slabs. Be careful to hold the 2342 * correct lock while calling into the keg layer. 2343 */ 2344 LIST_FOREACH(klink, &zone->uz_kegs, kl_link) { 2345 keg = klink->kl_keg; 2346 keg_relock(keg, zone); 2347 if ((keg->uk_flags & UMA_ZFLAG_FULL) == 0) { 2348 slab = keg_fetch_slab(keg, zone, flags); 2349 if (slab) 2350 return (slab); 2351 } 2352 if (keg->uk_flags & UMA_ZFLAG_FULL) 2353 full++; 2354 else 2355 empty++; 2356 zone_relock(zone, keg); 2357 } 2358 if (rflags & (M_NOWAIT | M_NOVM)) 2359 break; 2360 flags = rflags; 2361 /* 2362 * All kegs are full. XXX We can't atomically check all kegs 2363 * and sleep so just sleep for a short period and retry. 2364 */ 2365 if (full && !empty) { 2366 zone->uz_flags |= UMA_ZFLAG_FULL; 2367 zone->uz_sleeps++; 2368 zone_log_warning(zone); 2369 msleep(zone, zone->uz_lock, PVM, "zonelimit", hz/100); 2370 zone->uz_flags &= ~UMA_ZFLAG_FULL; 2371 continue; 2372 } 2373 } 2374 return (NULL); 2375 } 2376 2377 static void * 2378 slab_alloc_item(uma_zone_t zone, uma_slab_t slab) 2379 { 2380 uma_keg_t keg; 2381 uma_slabrefcnt_t slabref; 2382 void *item; 2383 u_int8_t freei; 2384 2385 keg = slab->us_keg; 2386 mtx_assert(&keg->uk_lock, MA_OWNED); 2387 2388 freei = slab->us_firstfree; 2389 if (keg->uk_flags & UMA_ZONE_REFCNT) { 2390 slabref = (uma_slabrefcnt_t)slab; 2391 slab->us_firstfree = slabref->us_freelist[freei].us_item; 2392 } else { 2393 slab->us_firstfree = slab->us_freelist[freei].us_item; 2394 } 2395 item = slab->us_data + (keg->uk_rsize * freei); 2396 2397 slab->us_freecount--; 2398 keg->uk_free--; 2399 #ifdef INVARIANTS 2400 uma_dbg_alloc(zone, slab, item); 2401 #endif 2402 /* Move this slab to the full list */ 2403 if (slab->us_freecount == 0) { 2404 LIST_REMOVE(slab, us_link); 2405 LIST_INSERT_HEAD(&keg->uk_full_slab, slab, us_link); 2406 } 2407 2408 return (item); 2409 } 2410 2411 static int 2412 zone_alloc_bucket(uma_zone_t zone, int flags) 2413 { 2414 uma_bucket_t bucket; 2415 uma_slab_t slab; 2416 uma_keg_t keg; 2417 int16_t saved; 2418 int max, origflags = flags; 2419 2420 /* 2421 * Try this zone's free list first so we don't allocate extra buckets. 2422 */ 2423 if ((bucket = LIST_FIRST(&zone->uz_free_bucket)) != NULL) { 2424 KASSERT(bucket->ub_cnt == 0, 2425 ("zone_alloc_bucket: Bucket on free list is not empty.")); 2426 LIST_REMOVE(bucket, ub_link); 2427 } else { 2428 int bflags; 2429 2430 bflags = (flags & ~M_ZERO); 2431 if (zone->uz_flags & UMA_ZFLAG_CACHEONLY) 2432 bflags |= M_NOVM; 2433 2434 ZONE_UNLOCK(zone); 2435 bucket = bucket_alloc(zone->uz_count, bflags); 2436 ZONE_LOCK(zone); 2437 } 2438 2439 if (bucket == NULL) { 2440 return (0); 2441 } 2442 2443 #ifdef SMP 2444 /* 2445 * This code is here to limit the number of simultaneous bucket fills 2446 * for any given zone to the number of per cpu caches in this zone. This 2447 * is done so that we don't allocate more memory than we really need. 2448 */ 2449 if (zone->uz_fills >= mp_ncpus) 2450 goto done; 2451 2452 #endif 2453 zone->uz_fills++; 2454 2455 max = MIN(bucket->ub_entries, zone->uz_count); 2456 /* Try to keep the buckets totally full */ 2457 saved = bucket->ub_cnt; 2458 slab = NULL; 2459 keg = NULL; 2460 while (bucket->ub_cnt < max && 2461 (slab = zone->uz_slab(zone, keg, flags)) != NULL) { 2462 keg = slab->us_keg; 2463 while (slab->us_freecount && bucket->ub_cnt < max) { 2464 bucket->ub_bucket[bucket->ub_cnt++] = 2465 slab_alloc_item(zone, slab); 2466 } 2467 2468 /* Don't block on the next fill */ 2469 flags |= M_NOWAIT; 2470 } 2471 if (slab) 2472 zone_relock(zone, keg); 2473 2474 /* 2475 * We unlock here because we need to call the zone's init. 2476 * It should be safe to unlock because the slab dealt with 2477 * above is already on the appropriate list within the keg 2478 * and the bucket we filled is not yet on any list, so we 2479 * own it. 2480 */ 2481 if (zone->uz_init != NULL) { 2482 int i; 2483 2484 ZONE_UNLOCK(zone); 2485 for (i = saved; i < bucket->ub_cnt; i++) 2486 if (zone->uz_init(bucket->ub_bucket[i], zone->uz_size, 2487 origflags) != 0) 2488 break; 2489 /* 2490 * If we couldn't initialize the whole bucket, put the 2491 * rest back onto the freelist. 2492 */ 2493 if (i != bucket->ub_cnt) { 2494 int j; 2495 2496 for (j = i; j < bucket->ub_cnt; j++) { 2497 zone_free_item(zone, bucket->ub_bucket[j], 2498 NULL, SKIP_FINI, 0); 2499 #ifdef INVARIANTS 2500 bucket->ub_bucket[j] = NULL; 2501 #endif 2502 } 2503 bucket->ub_cnt = i; 2504 } 2505 ZONE_LOCK(zone); 2506 } 2507 2508 zone->uz_fills--; 2509 if (bucket->ub_cnt != 0) { 2510 LIST_INSERT_HEAD(&zone->uz_full_bucket, 2511 bucket, ub_link); 2512 return (1); 2513 } 2514 #ifdef SMP 2515 done: 2516 #endif 2517 bucket_free(bucket); 2518 2519 return (0); 2520 } 2521 /* 2522 * Allocates an item for an internal zone 2523 * 2524 * Arguments 2525 * zone The zone to alloc for. 2526 * udata The data to be passed to the constructor. 2527 * flags M_WAITOK, M_NOWAIT, M_ZERO. 2528 * 2529 * Returns 2530 * NULL if there is no memory and M_NOWAIT is set 2531 * An item if successful 2532 */ 2533 2534 static void * 2535 zone_alloc_item(uma_zone_t zone, void *udata, int flags) 2536 { 2537 uma_slab_t slab; 2538 void *item; 2539 2540 item = NULL; 2541 2542 #ifdef UMA_DEBUG_ALLOC 2543 printf("INTERNAL: Allocating one item from %s(%p)\n", zone->uz_name, zone); 2544 #endif 2545 ZONE_LOCK(zone); 2546 2547 slab = zone->uz_slab(zone, NULL, flags); 2548 if (slab == NULL) { 2549 zone->uz_fails++; 2550 ZONE_UNLOCK(zone); 2551 return (NULL); 2552 } 2553 2554 item = slab_alloc_item(zone, slab); 2555 2556 zone_relock(zone, slab->us_keg); 2557 zone->uz_allocs++; 2558 ZONE_UNLOCK(zone); 2559 2560 /* 2561 * We have to call both the zone's init (not the keg's init) 2562 * and the zone's ctor. This is because the item is going from 2563 * a keg slab directly to the user, and the user is expecting it 2564 * to be both zone-init'd as well as zone-ctor'd. 2565 */ 2566 if (zone->uz_init != NULL) { 2567 if (zone->uz_init(item, zone->uz_size, flags) != 0) { 2568 zone_free_item(zone, item, udata, SKIP_FINI, 2569 ZFREE_STATFAIL | ZFREE_STATFREE); 2570 return (NULL); 2571 } 2572 } 2573 if (zone->uz_ctor != NULL) { 2574 if (zone->uz_ctor(item, zone->uz_size, udata, flags) != 0) { 2575 zone_free_item(zone, item, udata, SKIP_DTOR, 2576 ZFREE_STATFAIL | ZFREE_STATFREE); 2577 return (NULL); 2578 } 2579 } 2580 if (flags & M_ZERO) 2581 bzero(item, zone->uz_size); 2582 2583 return (item); 2584 } 2585 2586 /* See uma.h */ 2587 void 2588 uma_zfree_arg(uma_zone_t zone, void *item, void *udata) 2589 { 2590 uma_cache_t cache; 2591 uma_bucket_t bucket; 2592 int bflags; 2593 int cpu; 2594 2595 #ifdef UMA_DEBUG_ALLOC_1 2596 printf("Freeing item %p to %s(%p)\n", item, zone->uz_name, zone); 2597 #endif 2598 CTR2(KTR_UMA, "uma_zfree_arg thread %x zone %s", curthread, 2599 zone->uz_name); 2600 2601 /* uma_zfree(..., NULL) does nothing, to match free(9). */ 2602 if (item == NULL) 2603 return; 2604 #ifdef DEBUG_MEMGUARD 2605 if (is_memguard_addr(item)) { 2606 if (zone->uz_dtor != NULL && zone->uz_dtor != mtrash_dtor) 2607 zone->uz_dtor(item, zone->uz_size, udata); 2608 if (zone->uz_fini != NULL && zone->uz_fini != mtrash_fini) 2609 zone->uz_fini(item, zone->uz_size); 2610 memguard_free(item); 2611 return; 2612 } 2613 #endif 2614 if (zone->uz_dtor) 2615 zone->uz_dtor(item, zone->uz_size, udata); 2616 2617 #ifdef INVARIANTS 2618 ZONE_LOCK(zone); 2619 if (zone->uz_flags & UMA_ZONE_MALLOC) 2620 uma_dbg_free(zone, udata, item); 2621 else 2622 uma_dbg_free(zone, NULL, item); 2623 ZONE_UNLOCK(zone); 2624 #endif 2625 /* 2626 * The race here is acceptable. If we miss it we'll just have to wait 2627 * a little longer for the limits to be reset. 2628 */ 2629 if (zone->uz_flags & UMA_ZFLAG_FULL) 2630 goto zfree_internal; 2631 2632 /* 2633 * If possible, free to the per-CPU cache. There are two 2634 * requirements for safe access to the per-CPU cache: (1) the thread 2635 * accessing the cache must not be preempted or yield during access, 2636 * and (2) the thread must not migrate CPUs without switching which 2637 * cache it accesses. We rely on a critical section to prevent 2638 * preemption and migration. We release the critical section in 2639 * order to acquire the zone mutex if we are unable to free to the 2640 * current cache; when we re-acquire the critical section, we must 2641 * detect and handle migration if it has occurred. 2642 */ 2643 zfree_restart: 2644 critical_enter(); 2645 cpu = curcpu; 2646 cache = &zone->uz_cpu[cpu]; 2647 2648 zfree_start: 2649 bucket = cache->uc_freebucket; 2650 2651 if (bucket) { 2652 /* 2653 * Do we have room in our bucket? It is OK for this uz count 2654 * check to be slightly out of sync. 2655 */ 2656 2657 if (bucket->ub_cnt < bucket->ub_entries) { 2658 KASSERT(bucket->ub_bucket[bucket->ub_cnt] == NULL, 2659 ("uma_zfree: Freeing to non free bucket index.")); 2660 bucket->ub_bucket[bucket->ub_cnt] = item; 2661 bucket->ub_cnt++; 2662 cache->uc_frees++; 2663 critical_exit(); 2664 return; 2665 } else if (cache->uc_allocbucket) { 2666 #ifdef UMA_DEBUG_ALLOC 2667 printf("uma_zfree: Swapping buckets.\n"); 2668 #endif 2669 /* 2670 * We have run out of space in our freebucket. 2671 * See if we can switch with our alloc bucket. 2672 */ 2673 if (cache->uc_allocbucket->ub_cnt < 2674 cache->uc_freebucket->ub_cnt) { 2675 bucket = cache->uc_freebucket; 2676 cache->uc_freebucket = cache->uc_allocbucket; 2677 cache->uc_allocbucket = bucket; 2678 goto zfree_start; 2679 } 2680 } 2681 } 2682 /* 2683 * We can get here for two reasons: 2684 * 2685 * 1) The buckets are NULL 2686 * 2) The alloc and free buckets are both somewhat full. 2687 * 2688 * We must go back the zone, which requires acquiring the zone lock, 2689 * which in turn means we must release and re-acquire the critical 2690 * section. Since the critical section is released, we may be 2691 * preempted or migrate. As such, make sure not to maintain any 2692 * thread-local state specific to the cache from prior to releasing 2693 * the critical section. 2694 */ 2695 critical_exit(); 2696 ZONE_LOCK(zone); 2697 critical_enter(); 2698 cpu = curcpu; 2699 cache = &zone->uz_cpu[cpu]; 2700 if (cache->uc_freebucket != NULL) { 2701 if (cache->uc_freebucket->ub_cnt < 2702 cache->uc_freebucket->ub_entries) { 2703 ZONE_UNLOCK(zone); 2704 goto zfree_start; 2705 } 2706 if (cache->uc_allocbucket != NULL && 2707 (cache->uc_allocbucket->ub_cnt < 2708 cache->uc_freebucket->ub_cnt)) { 2709 ZONE_UNLOCK(zone); 2710 goto zfree_start; 2711 } 2712 } 2713 2714 /* Since we have locked the zone we may as well send back our stats */ 2715 zone->uz_allocs += cache->uc_allocs; 2716 cache->uc_allocs = 0; 2717 zone->uz_frees += cache->uc_frees; 2718 cache->uc_frees = 0; 2719 2720 bucket = cache->uc_freebucket; 2721 cache->uc_freebucket = NULL; 2722 2723 /* Can we throw this on the zone full list? */ 2724 if (bucket != NULL) { 2725 #ifdef UMA_DEBUG_ALLOC 2726 printf("uma_zfree: Putting old bucket on the free list.\n"); 2727 #endif 2728 /* ub_cnt is pointing to the last free item */ 2729 KASSERT(bucket->ub_cnt != 0, 2730 ("uma_zfree: Attempting to insert an empty bucket onto the full list.\n")); 2731 LIST_INSERT_HEAD(&zone->uz_full_bucket, 2732 bucket, ub_link); 2733 } 2734 if ((bucket = LIST_FIRST(&zone->uz_free_bucket)) != NULL) { 2735 LIST_REMOVE(bucket, ub_link); 2736 ZONE_UNLOCK(zone); 2737 cache->uc_freebucket = bucket; 2738 goto zfree_start; 2739 } 2740 /* We are no longer associated with this CPU. */ 2741 critical_exit(); 2742 2743 /* And the zone.. */ 2744 ZONE_UNLOCK(zone); 2745 2746 #ifdef UMA_DEBUG_ALLOC 2747 printf("uma_zfree: Allocating new free bucket.\n"); 2748 #endif 2749 bflags = M_NOWAIT; 2750 2751 if (zone->uz_flags & UMA_ZFLAG_CACHEONLY) 2752 bflags |= M_NOVM; 2753 bucket = bucket_alloc(zone->uz_count, bflags); 2754 if (bucket) { 2755 ZONE_LOCK(zone); 2756 LIST_INSERT_HEAD(&zone->uz_free_bucket, 2757 bucket, ub_link); 2758 ZONE_UNLOCK(zone); 2759 goto zfree_restart; 2760 } 2761 2762 /* 2763 * If nothing else caught this, we'll just do an internal free. 2764 */ 2765 zfree_internal: 2766 zone_free_item(zone, item, udata, SKIP_DTOR, ZFREE_STATFREE); 2767 2768 return; 2769 } 2770 2771 /* 2772 * Frees an item to an INTERNAL zone or allocates a free bucket 2773 * 2774 * Arguments: 2775 * zone The zone to free to 2776 * item The item we're freeing 2777 * udata User supplied data for the dtor 2778 * skip Skip dtors and finis 2779 */ 2780 static void 2781 zone_free_item(uma_zone_t zone, void *item, void *udata, 2782 enum zfreeskip skip, int flags) 2783 { 2784 uma_slab_t slab; 2785 uma_slabrefcnt_t slabref; 2786 uma_keg_t keg; 2787 u_int8_t *mem; 2788 u_int8_t freei; 2789 int clearfull; 2790 2791 if (skip < SKIP_DTOR && zone->uz_dtor) 2792 zone->uz_dtor(item, zone->uz_size, udata); 2793 2794 if (skip < SKIP_FINI && zone->uz_fini) 2795 zone->uz_fini(item, zone->uz_size); 2796 2797 ZONE_LOCK(zone); 2798 2799 if (flags & ZFREE_STATFAIL) 2800 zone->uz_fails++; 2801 if (flags & ZFREE_STATFREE) 2802 zone->uz_frees++; 2803 2804 if (!(zone->uz_flags & UMA_ZONE_VTOSLAB)) { 2805 mem = (u_int8_t *)((unsigned long)item & (~UMA_SLAB_MASK)); 2806 keg = zone_first_keg(zone); /* Must only be one. */ 2807 if (zone->uz_flags & UMA_ZONE_HASH) { 2808 slab = hash_sfind(&keg->uk_hash, mem); 2809 } else { 2810 mem += keg->uk_pgoff; 2811 slab = (uma_slab_t)mem; 2812 } 2813 } else { 2814 /* This prevents redundant lookups via free(). */ 2815 if ((zone->uz_flags & UMA_ZONE_MALLOC) && udata != NULL) 2816 slab = (uma_slab_t)udata; 2817 else 2818 slab = vtoslab((vm_offset_t)item); 2819 keg = slab->us_keg; 2820 keg_relock(keg, zone); 2821 } 2822 MPASS(keg == slab->us_keg); 2823 2824 /* Do we need to remove from any lists? */ 2825 if (slab->us_freecount+1 == keg->uk_ipers) { 2826 LIST_REMOVE(slab, us_link); 2827 LIST_INSERT_HEAD(&keg->uk_free_slab, slab, us_link); 2828 } else if (slab->us_freecount == 0) { 2829 LIST_REMOVE(slab, us_link); 2830 LIST_INSERT_HEAD(&keg->uk_part_slab, slab, us_link); 2831 } 2832 2833 /* Slab management stuff */ 2834 freei = ((unsigned long)item - (unsigned long)slab->us_data) 2835 / keg->uk_rsize; 2836 2837 #ifdef INVARIANTS 2838 if (!skip) 2839 uma_dbg_free(zone, slab, item); 2840 #endif 2841 2842 if (keg->uk_flags & UMA_ZONE_REFCNT) { 2843 slabref = (uma_slabrefcnt_t)slab; 2844 slabref->us_freelist[freei].us_item = slab->us_firstfree; 2845 } else { 2846 slab->us_freelist[freei].us_item = slab->us_firstfree; 2847 } 2848 slab->us_firstfree = freei; 2849 slab->us_freecount++; 2850 2851 /* Zone statistics */ 2852 keg->uk_free++; 2853 2854 clearfull = 0; 2855 if (keg->uk_flags & UMA_ZFLAG_FULL) { 2856 if (keg->uk_pages < keg->uk_maxpages) { 2857 keg->uk_flags &= ~UMA_ZFLAG_FULL; 2858 clearfull = 1; 2859 } 2860 2861 /* 2862 * We can handle one more allocation. Since we're clearing ZFLAG_FULL, 2863 * wake up all procs blocked on pages. This should be uncommon, so 2864 * keeping this simple for now (rather than adding count of blocked 2865 * threads etc). 2866 */ 2867 wakeup(keg); 2868 } 2869 if (clearfull) { 2870 zone_relock(zone, keg); 2871 zone->uz_flags &= ~UMA_ZFLAG_FULL; 2872 wakeup(zone); 2873 ZONE_UNLOCK(zone); 2874 } else 2875 KEG_UNLOCK(keg); 2876 } 2877 2878 /* See uma.h */ 2879 int 2880 uma_zone_set_max(uma_zone_t zone, int nitems) 2881 { 2882 uma_keg_t keg; 2883 2884 ZONE_LOCK(zone); 2885 keg = zone_first_keg(zone); 2886 keg->uk_maxpages = (nitems / keg->uk_ipers) * keg->uk_ppera; 2887 if (keg->uk_maxpages * keg->uk_ipers < nitems) 2888 keg->uk_maxpages += keg->uk_ppera; 2889 nitems = keg->uk_maxpages * keg->uk_ipers; 2890 ZONE_UNLOCK(zone); 2891 2892 return (nitems); 2893 } 2894 2895 /* See uma.h */ 2896 int 2897 uma_zone_get_max(uma_zone_t zone) 2898 { 2899 int nitems; 2900 uma_keg_t keg; 2901 2902 ZONE_LOCK(zone); 2903 keg = zone_first_keg(zone); 2904 nitems = keg->uk_maxpages * keg->uk_ipers; 2905 ZONE_UNLOCK(zone); 2906 2907 return (nitems); 2908 } 2909 2910 /* See uma.h */ 2911 void 2912 uma_zone_set_warning(uma_zone_t zone, const char *warning) 2913 { 2914 2915 ZONE_LOCK(zone); 2916 zone->uz_warning = warning; 2917 ZONE_UNLOCK(zone); 2918 } 2919 2920 /* See uma.h */ 2921 int 2922 uma_zone_get_cur(uma_zone_t zone) 2923 { 2924 int64_t nitems; 2925 u_int i; 2926 2927 ZONE_LOCK(zone); 2928 nitems = zone->uz_allocs - zone->uz_frees; 2929 CPU_FOREACH(i) { 2930 /* 2931 * See the comment in sysctl_vm_zone_stats() regarding the 2932 * safety of accessing the per-cpu caches. With the zone lock 2933 * held, it is safe, but can potentially result in stale data. 2934 */ 2935 nitems += zone->uz_cpu[i].uc_allocs - 2936 zone->uz_cpu[i].uc_frees; 2937 } 2938 ZONE_UNLOCK(zone); 2939 2940 return (nitems < 0 ? 0 : nitems); 2941 } 2942 2943 /* See uma.h */ 2944 void 2945 uma_zone_set_init(uma_zone_t zone, uma_init uminit) 2946 { 2947 uma_keg_t keg; 2948 2949 ZONE_LOCK(zone); 2950 keg = zone_first_keg(zone); 2951 KASSERT(keg->uk_pages == 0, 2952 ("uma_zone_set_init on non-empty keg")); 2953 keg->uk_init = uminit; 2954 ZONE_UNLOCK(zone); 2955 } 2956 2957 /* See uma.h */ 2958 void 2959 uma_zone_set_fini(uma_zone_t zone, uma_fini fini) 2960 { 2961 uma_keg_t keg; 2962 2963 ZONE_LOCK(zone); 2964 keg = zone_first_keg(zone); 2965 KASSERT(keg->uk_pages == 0, 2966 ("uma_zone_set_fini on non-empty keg")); 2967 keg->uk_fini = fini; 2968 ZONE_UNLOCK(zone); 2969 } 2970 2971 /* See uma.h */ 2972 void 2973 uma_zone_set_zinit(uma_zone_t zone, uma_init zinit) 2974 { 2975 ZONE_LOCK(zone); 2976 KASSERT(zone_first_keg(zone)->uk_pages == 0, 2977 ("uma_zone_set_zinit on non-empty keg")); 2978 zone->uz_init = zinit; 2979 ZONE_UNLOCK(zone); 2980 } 2981 2982 /* See uma.h */ 2983 void 2984 uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini) 2985 { 2986 ZONE_LOCK(zone); 2987 KASSERT(zone_first_keg(zone)->uk_pages == 0, 2988 ("uma_zone_set_zfini on non-empty keg")); 2989 zone->uz_fini = zfini; 2990 ZONE_UNLOCK(zone); 2991 } 2992 2993 /* See uma.h */ 2994 /* XXX uk_freef is not actually used with the zone locked */ 2995 void 2996 uma_zone_set_freef(uma_zone_t zone, uma_free freef) 2997 { 2998 2999 ZONE_LOCK(zone); 3000 zone_first_keg(zone)->uk_freef = freef; 3001 ZONE_UNLOCK(zone); 3002 } 3003 3004 /* See uma.h */ 3005 /* XXX uk_allocf is not actually used with the zone locked */ 3006 void 3007 uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf) 3008 { 3009 uma_keg_t keg; 3010 3011 ZONE_LOCK(zone); 3012 keg = zone_first_keg(zone); 3013 keg->uk_flags |= UMA_ZFLAG_PRIVALLOC; 3014 keg->uk_allocf = allocf; 3015 ZONE_UNLOCK(zone); 3016 } 3017 3018 /* See uma.h */ 3019 int 3020 uma_zone_reserve_kva(uma_zone_t zone, int count) 3021 { 3022 uma_keg_t keg; 3023 vm_offset_t kva; 3024 int pages; 3025 3026 keg = zone_first_keg(zone); 3027 pages = count / keg->uk_ipers; 3028 3029 if (pages * keg->uk_ipers < count) 3030 pages++; 3031 3032 #ifdef UMA_MD_SMALL_ALLOC 3033 if (keg->uk_ppera > 1) { 3034 #else 3035 if (1) { 3036 #endif 3037 kva = kmem_alloc_nofault(kernel_map, pages * UMA_SLAB_SIZE); 3038 if (kva == 0) 3039 return (0); 3040 } else 3041 kva = 0; 3042 ZONE_LOCK(zone); 3043 keg->uk_kva = kva; 3044 keg->uk_offset = 0; 3045 keg->uk_maxpages = pages; 3046 #ifdef UMA_MD_SMALL_ALLOC 3047 keg->uk_allocf = (keg->uk_ppera > 1) ? noobj_alloc : uma_small_alloc; 3048 #else 3049 keg->uk_allocf = noobj_alloc; 3050 #endif 3051 keg->uk_flags |= UMA_ZONE_NOFREE | UMA_ZFLAG_PRIVALLOC; 3052 ZONE_UNLOCK(zone); 3053 return (1); 3054 } 3055 3056 /* See uma.h */ 3057 void 3058 uma_prealloc(uma_zone_t zone, int items) 3059 { 3060 int slabs; 3061 uma_slab_t slab; 3062 uma_keg_t keg; 3063 3064 keg = zone_first_keg(zone); 3065 ZONE_LOCK(zone); 3066 slabs = items / keg->uk_ipers; 3067 if (slabs * keg->uk_ipers < items) 3068 slabs++; 3069 while (slabs > 0) { 3070 slab = keg_alloc_slab(keg, zone, M_WAITOK); 3071 if (slab == NULL) 3072 break; 3073 MPASS(slab->us_keg == keg); 3074 LIST_INSERT_HEAD(&keg->uk_free_slab, slab, us_link); 3075 slabs--; 3076 } 3077 ZONE_UNLOCK(zone); 3078 } 3079 3080 /* See uma.h */ 3081 u_int32_t * 3082 uma_find_refcnt(uma_zone_t zone, void *item) 3083 { 3084 uma_slabrefcnt_t slabref; 3085 uma_keg_t keg; 3086 u_int32_t *refcnt; 3087 int idx; 3088 3089 slabref = (uma_slabrefcnt_t)vtoslab((vm_offset_t)item & 3090 (~UMA_SLAB_MASK)); 3091 keg = slabref->us_keg; 3092 KASSERT(slabref != NULL && slabref->us_keg->uk_flags & UMA_ZONE_REFCNT, 3093 ("uma_find_refcnt(): zone possibly not UMA_ZONE_REFCNT")); 3094 idx = ((unsigned long)item - (unsigned long)slabref->us_data) 3095 / keg->uk_rsize; 3096 refcnt = &slabref->us_freelist[idx].us_refcnt; 3097 return refcnt; 3098 } 3099 3100 /* See uma.h */ 3101 void 3102 uma_reclaim(void) 3103 { 3104 #ifdef UMA_DEBUG 3105 printf("UMA: vm asked us to release pages!\n"); 3106 #endif 3107 bucket_enable(); 3108 zone_foreach(zone_drain); 3109 /* 3110 * Some slabs may have been freed but this zone will be visited early 3111 * we visit again so that we can free pages that are empty once other 3112 * zones are drained. We have to do the same for buckets. 3113 */ 3114 zone_drain(slabzone); 3115 zone_drain(slabrefzone); 3116 bucket_zone_drain(); 3117 } 3118 3119 /* See uma.h */ 3120 int 3121 uma_zone_exhausted(uma_zone_t zone) 3122 { 3123 int full; 3124 3125 ZONE_LOCK(zone); 3126 full = (zone->uz_flags & UMA_ZFLAG_FULL); 3127 ZONE_UNLOCK(zone); 3128 return (full); 3129 } 3130 3131 int 3132 uma_zone_exhausted_nolock(uma_zone_t zone) 3133 { 3134 return (zone->uz_flags & UMA_ZFLAG_FULL); 3135 } 3136 3137 void * 3138 uma_large_malloc(int size, int wait) 3139 { 3140 void *mem; 3141 uma_slab_t slab; 3142 u_int8_t flags; 3143 3144 slab = zone_alloc_item(slabzone, NULL, wait); 3145 if (slab == NULL) 3146 return (NULL); 3147 mem = page_alloc(NULL, size, &flags, wait); 3148 if (mem) { 3149 vsetslab((vm_offset_t)mem, slab); 3150 slab->us_data = mem; 3151 slab->us_flags = flags | UMA_SLAB_MALLOC; 3152 slab->us_size = size; 3153 } else { 3154 zone_free_item(slabzone, slab, NULL, SKIP_NONE, 3155 ZFREE_STATFAIL | ZFREE_STATFREE); 3156 } 3157 3158 return (mem); 3159 } 3160 3161 void 3162 uma_large_free(uma_slab_t slab) 3163 { 3164 vsetobj((vm_offset_t)slab->us_data, kmem_object); 3165 page_free(slab->us_data, slab->us_size, slab->us_flags); 3166 zone_free_item(slabzone, slab, NULL, SKIP_NONE, ZFREE_STATFREE); 3167 } 3168 3169 void 3170 uma_print_stats(void) 3171 { 3172 zone_foreach(uma_print_zone); 3173 } 3174 3175 static void 3176 slab_print(uma_slab_t slab) 3177 { 3178 printf("slab: keg %p, data %p, freecount %d, firstfree %d\n", 3179 slab->us_keg, slab->us_data, slab->us_freecount, 3180 slab->us_firstfree); 3181 } 3182 3183 static void 3184 cache_print(uma_cache_t cache) 3185 { 3186 printf("alloc: %p(%d), free: %p(%d)\n", 3187 cache->uc_allocbucket, 3188 cache->uc_allocbucket?cache->uc_allocbucket->ub_cnt:0, 3189 cache->uc_freebucket, 3190 cache->uc_freebucket?cache->uc_freebucket->ub_cnt:0); 3191 } 3192 3193 static void 3194 uma_print_keg(uma_keg_t keg) 3195 { 3196 uma_slab_t slab; 3197 3198 printf("keg: %s(%p) size %d(%d) flags %#x ipers %d ppera %d " 3199 "out %d free %d limit %d\n", 3200 keg->uk_name, keg, keg->uk_size, keg->uk_rsize, keg->uk_flags, 3201 keg->uk_ipers, keg->uk_ppera, 3202 (keg->uk_ipers * keg->uk_pages) - keg->uk_free, keg->uk_free, 3203 (keg->uk_maxpages / keg->uk_ppera) * keg->uk_ipers); 3204 printf("Part slabs:\n"); 3205 LIST_FOREACH(slab, &keg->uk_part_slab, us_link) 3206 slab_print(slab); 3207 printf("Free slabs:\n"); 3208 LIST_FOREACH(slab, &keg->uk_free_slab, us_link) 3209 slab_print(slab); 3210 printf("Full slabs:\n"); 3211 LIST_FOREACH(slab, &keg->uk_full_slab, us_link) 3212 slab_print(slab); 3213 } 3214 3215 void 3216 uma_print_zone(uma_zone_t zone) 3217 { 3218 uma_cache_t cache; 3219 uma_klink_t kl; 3220 int i; 3221 3222 printf("zone: %s(%p) size %d flags %#x\n", 3223 zone->uz_name, zone, zone->uz_size, zone->uz_flags); 3224 LIST_FOREACH(kl, &zone->uz_kegs, kl_link) 3225 uma_print_keg(kl->kl_keg); 3226 CPU_FOREACH(i) { 3227 cache = &zone->uz_cpu[i]; 3228 printf("CPU %d Cache:\n", i); 3229 cache_print(cache); 3230 } 3231 } 3232 3233 #ifdef DDB 3234 /* 3235 * Generate statistics across both the zone and its per-cpu cache's. Return 3236 * desired statistics if the pointer is non-NULL for that statistic. 3237 * 3238 * Note: does not update the zone statistics, as it can't safely clear the 3239 * per-CPU cache statistic. 3240 * 3241 * XXXRW: Following the uc_allocbucket and uc_freebucket pointers here isn't 3242 * safe from off-CPU; we should modify the caches to track this information 3243 * directly so that we don't have to. 3244 */ 3245 static void 3246 uma_zone_sumstat(uma_zone_t z, int *cachefreep, u_int64_t *allocsp, 3247 u_int64_t *freesp, u_int64_t *sleepsp) 3248 { 3249 uma_cache_t cache; 3250 u_int64_t allocs, frees, sleeps; 3251 int cachefree, cpu; 3252 3253 allocs = frees = sleeps = 0; 3254 cachefree = 0; 3255 CPU_FOREACH(cpu) { 3256 cache = &z->uz_cpu[cpu]; 3257 if (cache->uc_allocbucket != NULL) 3258 cachefree += cache->uc_allocbucket->ub_cnt; 3259 if (cache->uc_freebucket != NULL) 3260 cachefree += cache->uc_freebucket->ub_cnt; 3261 allocs += cache->uc_allocs; 3262 frees += cache->uc_frees; 3263 } 3264 allocs += z->uz_allocs; 3265 frees += z->uz_frees; 3266 sleeps += z->uz_sleeps; 3267 if (cachefreep != NULL) 3268 *cachefreep = cachefree; 3269 if (allocsp != NULL) 3270 *allocsp = allocs; 3271 if (freesp != NULL) 3272 *freesp = frees; 3273 if (sleepsp != NULL) 3274 *sleepsp = sleeps; 3275 } 3276 #endif /* DDB */ 3277 3278 static int 3279 sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS) 3280 { 3281 uma_keg_t kz; 3282 uma_zone_t z; 3283 int count; 3284 3285 count = 0; 3286 mtx_lock(&uma_mtx); 3287 LIST_FOREACH(kz, &uma_kegs, uk_link) { 3288 LIST_FOREACH(z, &kz->uk_zones, uz_link) 3289 count++; 3290 } 3291 mtx_unlock(&uma_mtx); 3292 return (sysctl_handle_int(oidp, &count, 0, req)); 3293 } 3294 3295 static int 3296 sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS) 3297 { 3298 struct uma_stream_header ush; 3299 struct uma_type_header uth; 3300 struct uma_percpu_stat ups; 3301 uma_bucket_t bucket; 3302 struct sbuf sbuf; 3303 uma_cache_t cache; 3304 uma_klink_t kl; 3305 uma_keg_t kz; 3306 uma_zone_t z; 3307 uma_keg_t k; 3308 int count, error, i; 3309 3310 error = sysctl_wire_old_buffer(req, 0); 3311 if (error != 0) 3312 return (error); 3313 sbuf_new_for_sysctl(&sbuf, NULL, 128, req); 3314 3315 count = 0; 3316 mtx_lock(&uma_mtx); 3317 LIST_FOREACH(kz, &uma_kegs, uk_link) { 3318 LIST_FOREACH(z, &kz->uk_zones, uz_link) 3319 count++; 3320 } 3321 3322 /* 3323 * Insert stream header. 3324 */ 3325 bzero(&ush, sizeof(ush)); 3326 ush.ush_version = UMA_STREAM_VERSION; 3327 ush.ush_maxcpus = (mp_maxid + 1); 3328 ush.ush_count = count; 3329 (void)sbuf_bcat(&sbuf, &ush, sizeof(ush)); 3330 3331 LIST_FOREACH(kz, &uma_kegs, uk_link) { 3332 LIST_FOREACH(z, &kz->uk_zones, uz_link) { 3333 bzero(&uth, sizeof(uth)); 3334 ZONE_LOCK(z); 3335 strlcpy(uth.uth_name, z->uz_name, UTH_MAX_NAME); 3336 uth.uth_align = kz->uk_align; 3337 uth.uth_size = kz->uk_size; 3338 uth.uth_rsize = kz->uk_rsize; 3339 LIST_FOREACH(kl, &z->uz_kegs, kl_link) { 3340 k = kl->kl_keg; 3341 uth.uth_maxpages += k->uk_maxpages; 3342 uth.uth_pages += k->uk_pages; 3343 uth.uth_keg_free += k->uk_free; 3344 uth.uth_limit = (k->uk_maxpages / k->uk_ppera) 3345 * k->uk_ipers; 3346 } 3347 3348 /* 3349 * A zone is secondary is it is not the first entry 3350 * on the keg's zone list. 3351 */ 3352 if ((z->uz_flags & UMA_ZONE_SECONDARY) && 3353 (LIST_FIRST(&kz->uk_zones) != z)) 3354 uth.uth_zone_flags = UTH_ZONE_SECONDARY; 3355 3356 LIST_FOREACH(bucket, &z->uz_full_bucket, ub_link) 3357 uth.uth_zone_free += bucket->ub_cnt; 3358 uth.uth_allocs = z->uz_allocs; 3359 uth.uth_frees = z->uz_frees; 3360 uth.uth_fails = z->uz_fails; 3361 uth.uth_sleeps = z->uz_sleeps; 3362 (void)sbuf_bcat(&sbuf, &uth, sizeof(uth)); 3363 /* 3364 * While it is not normally safe to access the cache 3365 * bucket pointers while not on the CPU that owns the 3366 * cache, we only allow the pointers to be exchanged 3367 * without the zone lock held, not invalidated, so 3368 * accept the possible race associated with bucket 3369 * exchange during monitoring. 3370 */ 3371 for (i = 0; i < (mp_maxid + 1); i++) { 3372 bzero(&ups, sizeof(ups)); 3373 if (kz->uk_flags & UMA_ZFLAG_INTERNAL) 3374 goto skip; 3375 if (CPU_ABSENT(i)) 3376 goto skip; 3377 cache = &z->uz_cpu[i]; 3378 if (cache->uc_allocbucket != NULL) 3379 ups.ups_cache_free += 3380 cache->uc_allocbucket->ub_cnt; 3381 if (cache->uc_freebucket != NULL) 3382 ups.ups_cache_free += 3383 cache->uc_freebucket->ub_cnt; 3384 ups.ups_allocs = cache->uc_allocs; 3385 ups.ups_frees = cache->uc_frees; 3386 skip: 3387 (void)sbuf_bcat(&sbuf, &ups, sizeof(ups)); 3388 } 3389 ZONE_UNLOCK(z); 3390 } 3391 } 3392 mtx_unlock(&uma_mtx); 3393 error = sbuf_finish(&sbuf); 3394 sbuf_delete(&sbuf); 3395 return (error); 3396 } 3397 3398 #ifdef DDB 3399 DB_SHOW_COMMAND(uma, db_show_uma) 3400 { 3401 u_int64_t allocs, frees, sleeps; 3402 uma_bucket_t bucket; 3403 uma_keg_t kz; 3404 uma_zone_t z; 3405 int cachefree; 3406 3407 db_printf("%18s %8s %8s %8s %12s %8s\n", "Zone", "Size", "Used", "Free", 3408 "Requests", "Sleeps"); 3409 LIST_FOREACH(kz, &uma_kegs, uk_link) { 3410 LIST_FOREACH(z, &kz->uk_zones, uz_link) { 3411 if (kz->uk_flags & UMA_ZFLAG_INTERNAL) { 3412 allocs = z->uz_allocs; 3413 frees = z->uz_frees; 3414 sleeps = z->uz_sleeps; 3415 cachefree = 0; 3416 } else 3417 uma_zone_sumstat(z, &cachefree, &allocs, 3418 &frees, &sleeps); 3419 if (!((z->uz_flags & UMA_ZONE_SECONDARY) && 3420 (LIST_FIRST(&kz->uk_zones) != z))) 3421 cachefree += kz->uk_free; 3422 LIST_FOREACH(bucket, &z->uz_full_bucket, ub_link) 3423 cachefree += bucket->ub_cnt; 3424 db_printf("%18s %8ju %8jd %8d %12ju %8ju\n", z->uz_name, 3425 (uintmax_t)kz->uk_size, 3426 (intmax_t)(allocs - frees), cachefree, 3427 (uintmax_t)allocs, sleeps); 3428 if (db_pager_quit) 3429 return; 3430 } 3431 } 3432 } 3433 #endif 3434