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