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) 2004-2005 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 void zone_drain(uma_zone_t); 242 static uma_zone_t uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit, 243 uma_fini fini, int align, u_int32_t flags); 244 245 void uma_print_zone(uma_zone_t); 246 void uma_print_stats(void); 247 static int sysctl_vm_zone(SYSCTL_HANDLER_ARGS); 248 static int sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS); 249 static int sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS); 250 251 #ifdef WITNESS 252 static int nosleepwithlocks = 1; 253 SYSCTL_INT(_debug, OID_AUTO, nosleepwithlocks, CTLFLAG_RW, &nosleepwithlocks, 254 0, "Convert M_WAITOK to M_NOWAIT to avoid lock-held-across-sleep paths"); 255 #else 256 static int nosleepwithlocks = 0; 257 SYSCTL_INT(_debug, OID_AUTO, nosleepwithlocks, CTLFLAG_RW, &nosleepwithlocks, 258 0, "Convert M_WAITOK to M_NOWAIT to avoid lock-held-across-sleep paths"); 259 #endif 260 SYSCTL_OID(_vm, OID_AUTO, zone, CTLTYPE_STRING|CTLFLAG_RD, 261 NULL, 0, sysctl_vm_zone, "A", "Zone Info"); 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 /* 271 * This routine checks to see whether or not it's safe to enable buckets. 272 */ 273 274 static void 275 bucket_enable(void) 276 { 277 if (cnt.v_free_count < cnt.v_free_min) 278 bucketdisable = 1; 279 else 280 bucketdisable = 0; 281 } 282 283 /* 284 * Initialize bucket_zones, the array of zones of buckets of various sizes. 285 * 286 * For each zone, calculate the memory required for each bucket, consisting 287 * of the header and an array of pointers. Initialize bucket_size[] to point 288 * the range of appropriate bucket sizes at the zone. 289 */ 290 static void 291 bucket_init(void) 292 { 293 struct uma_bucket_zone *ubz; 294 int i; 295 int j; 296 297 for (i = 0, j = 0; bucket_zones[j].ubz_entries != 0; j++) { 298 int size; 299 300 ubz = &bucket_zones[j]; 301 size = roundup(sizeof(struct uma_bucket), sizeof(void *)); 302 size += sizeof(void *) * ubz->ubz_entries; 303 ubz->ubz_zone = uma_zcreate(ubz->ubz_name, size, 304 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL); 305 for (; i <= ubz->ubz_entries; i += (1 << BUCKET_SHIFT)) 306 bucket_size[i >> BUCKET_SHIFT] = j; 307 } 308 } 309 310 /* 311 * Given a desired number of entries for a bucket, return the zone from which 312 * to allocate the bucket. 313 */ 314 static struct uma_bucket_zone * 315 bucket_zone_lookup(int entries) 316 { 317 int idx; 318 319 idx = howmany(entries, 1 << BUCKET_SHIFT); 320 return (&bucket_zones[bucket_size[idx]]); 321 } 322 323 static uma_bucket_t 324 bucket_alloc(int entries, int bflags) 325 { 326 struct uma_bucket_zone *ubz; 327 uma_bucket_t bucket; 328 329 /* 330 * This is to stop us from allocating per cpu buckets while we're 331 * running out of vm.boot_pages. Otherwise, we would exhaust the 332 * boot pages. This also prevents us from allocating buckets in 333 * low memory situations. 334 */ 335 if (bucketdisable) 336 return (NULL); 337 338 ubz = bucket_zone_lookup(entries); 339 bucket = uma_zalloc_internal(ubz->ubz_zone, NULL, bflags); 340 if (bucket) { 341 #ifdef INVARIANTS 342 bzero(bucket->ub_bucket, sizeof(void *) * ubz->ubz_entries); 343 #endif 344 bucket->ub_cnt = 0; 345 bucket->ub_entries = ubz->ubz_entries; 346 } 347 348 return (bucket); 349 } 350 351 static void 352 bucket_free(uma_bucket_t bucket) 353 { 354 struct uma_bucket_zone *ubz; 355 356 ubz = bucket_zone_lookup(bucket->ub_entries); 357 uma_zfree_internal(ubz->ubz_zone, bucket, NULL, SKIP_NONE, 358 ZFREE_STATFREE); 359 } 360 361 static void 362 bucket_zone_drain(void) 363 { 364 struct uma_bucket_zone *ubz; 365 366 for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++) 367 zone_drain(ubz->ubz_zone); 368 } 369 370 371 /* 372 * Routine called by timeout which is used to fire off some time interval 373 * based calculations. (stats, hash size, etc.) 374 * 375 * Arguments: 376 * arg Unused 377 * 378 * Returns: 379 * Nothing 380 */ 381 static void 382 uma_timeout(void *unused) 383 { 384 bucket_enable(); 385 zone_foreach(zone_timeout); 386 387 /* Reschedule this event */ 388 callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL); 389 } 390 391 /* 392 * Routine to perform timeout driven calculations. This expands the 393 * hashes and does per cpu statistics aggregation. 394 * 395 * Arguments: 396 * zone The zone to operate on 397 * 398 * Returns: 399 * Nothing 400 */ 401 static void 402 zone_timeout(uma_zone_t zone) 403 { 404 uma_keg_t keg; 405 u_int64_t alloc; 406 407 keg = zone->uz_keg; 408 alloc = 0; 409 410 /* 411 * Expand the zone hash table. 412 * 413 * This is done if the number of slabs is larger than the hash size. 414 * What I'm trying to do here is completely reduce collisions. This 415 * may be a little aggressive. Should I allow for two collisions max? 416 */ 417 ZONE_LOCK(zone); 418 if (keg->uk_flags & UMA_ZONE_HASH && 419 keg->uk_pages / keg->uk_ppera >= keg->uk_hash.uh_hashsize) { 420 struct uma_hash newhash; 421 struct uma_hash oldhash; 422 int ret; 423 424 /* 425 * This is so involved because allocating and freeing 426 * while the zone lock is held will lead to deadlock. 427 * I have to do everything in stages and check for 428 * races. 429 */ 430 newhash = keg->uk_hash; 431 ZONE_UNLOCK(zone); 432 ret = hash_alloc(&newhash); 433 ZONE_LOCK(zone); 434 if (ret) { 435 if (hash_expand(&keg->uk_hash, &newhash)) { 436 oldhash = keg->uk_hash; 437 keg->uk_hash = newhash; 438 } else 439 oldhash = newhash; 440 441 ZONE_UNLOCK(zone); 442 hash_free(&oldhash); 443 ZONE_LOCK(zone); 444 } 445 } 446 ZONE_UNLOCK(zone); 447 } 448 449 /* 450 * Allocate and zero fill the next sized hash table from the appropriate 451 * backing store. 452 * 453 * Arguments: 454 * hash A new hash structure with the old hash size in uh_hashsize 455 * 456 * Returns: 457 * 1 on sucess and 0 on failure. 458 */ 459 static int 460 hash_alloc(struct uma_hash *hash) 461 { 462 int oldsize; 463 int alloc; 464 465 oldsize = hash->uh_hashsize; 466 467 /* We're just going to go to a power of two greater */ 468 if (oldsize) { 469 hash->uh_hashsize = oldsize * 2; 470 alloc = sizeof(hash->uh_slab_hash[0]) * hash->uh_hashsize; 471 hash->uh_slab_hash = (struct slabhead *)malloc(alloc, 472 M_UMAHASH, M_NOWAIT); 473 } else { 474 alloc = sizeof(hash->uh_slab_hash[0]) * UMA_HASH_SIZE_INIT; 475 hash->uh_slab_hash = uma_zalloc_internal(hashzone, NULL, 476 M_WAITOK); 477 hash->uh_hashsize = UMA_HASH_SIZE_INIT; 478 } 479 if (hash->uh_slab_hash) { 480 bzero(hash->uh_slab_hash, alloc); 481 hash->uh_hashmask = hash->uh_hashsize - 1; 482 return (1); 483 } 484 485 return (0); 486 } 487 488 /* 489 * Expands the hash table for HASH zones. This is done from zone_timeout 490 * to reduce collisions. This must not be done in the regular allocation 491 * path, otherwise, we can recurse on the vm while allocating pages. 492 * 493 * Arguments: 494 * oldhash The hash you want to expand 495 * newhash The hash structure for the new table 496 * 497 * Returns: 498 * Nothing 499 * 500 * Discussion: 501 */ 502 static int 503 hash_expand(struct uma_hash *oldhash, struct uma_hash *newhash) 504 { 505 uma_slab_t slab; 506 int hval; 507 int i; 508 509 if (!newhash->uh_slab_hash) 510 return (0); 511 512 if (oldhash->uh_hashsize >= newhash->uh_hashsize) 513 return (0); 514 515 /* 516 * I need to investigate hash algorithms for resizing without a 517 * full rehash. 518 */ 519 520 for (i = 0; i < oldhash->uh_hashsize; i++) 521 while (!SLIST_EMPTY(&oldhash->uh_slab_hash[i])) { 522 slab = SLIST_FIRST(&oldhash->uh_slab_hash[i]); 523 SLIST_REMOVE_HEAD(&oldhash->uh_slab_hash[i], us_hlink); 524 hval = UMA_HASH(newhash, slab->us_data); 525 SLIST_INSERT_HEAD(&newhash->uh_slab_hash[hval], 526 slab, us_hlink); 527 } 528 529 return (1); 530 } 531 532 /* 533 * Free the hash bucket to the appropriate backing store. 534 * 535 * Arguments: 536 * slab_hash The hash bucket we're freeing 537 * hashsize The number of entries in that hash bucket 538 * 539 * Returns: 540 * Nothing 541 */ 542 static void 543 hash_free(struct uma_hash *hash) 544 { 545 if (hash->uh_slab_hash == NULL) 546 return; 547 if (hash->uh_hashsize == UMA_HASH_SIZE_INIT) 548 uma_zfree_internal(hashzone, 549 hash->uh_slab_hash, NULL, SKIP_NONE, ZFREE_STATFREE); 550 else 551 free(hash->uh_slab_hash, M_UMAHASH); 552 } 553 554 /* 555 * Frees all outstanding items in a bucket 556 * 557 * Arguments: 558 * zone The zone to free to, must be unlocked. 559 * bucket The free/alloc bucket with items, cpu queue must be locked. 560 * 561 * Returns: 562 * Nothing 563 */ 564 565 static void 566 bucket_drain(uma_zone_t zone, uma_bucket_t bucket) 567 { 568 uma_slab_t slab; 569 int mzone; 570 void *item; 571 572 if (bucket == NULL) 573 return; 574 575 slab = NULL; 576 mzone = 0; 577 578 /* We have to lookup the slab again for malloc.. */ 579 if (zone->uz_keg->uk_flags & UMA_ZONE_MALLOC) 580 mzone = 1; 581 582 while (bucket->ub_cnt > 0) { 583 bucket->ub_cnt--; 584 item = bucket->ub_bucket[bucket->ub_cnt]; 585 #ifdef INVARIANTS 586 bucket->ub_bucket[bucket->ub_cnt] = NULL; 587 KASSERT(item != NULL, 588 ("bucket_drain: botched ptr, item is NULL")); 589 #endif 590 /* 591 * This is extremely inefficient. The slab pointer was passed 592 * to uma_zfree_arg, but we lost it because the buckets don't 593 * hold them. This will go away when free() gets a size passed 594 * to it. 595 */ 596 if (mzone) 597 slab = vtoslab((vm_offset_t)item & (~UMA_SLAB_MASK)); 598 uma_zfree_internal(zone, item, slab, SKIP_DTOR, 0); 599 } 600 } 601 602 /* 603 * Drains the per cpu caches for a zone. 604 * 605 * NOTE: This may only be called while the zone is being turn down, and not 606 * during normal operation. This is necessary in order that we do not have 607 * to migrate CPUs to drain the per-CPU caches. 608 * 609 * Arguments: 610 * zone The zone to drain, must be unlocked. 611 * 612 * Returns: 613 * Nothing 614 */ 615 static void 616 cache_drain(uma_zone_t zone) 617 { 618 uma_cache_t cache; 619 int cpu; 620 621 /* 622 * XXX: It is safe to not lock the per-CPU caches, because we're 623 * tearing down the zone anyway. I.e., there will be no further use 624 * of the caches at this point. 625 * 626 * XXX: It would good to be able to assert that the zone is being 627 * torn down to prevent improper use of cache_drain(). 628 * 629 * XXX: We lock the zone before passing into bucket_cache_drain() as 630 * it is used elsewhere. Should the tear-down path be made special 631 * there in some form? 632 */ 633 for (cpu = 0; cpu <= mp_maxid; cpu++) { 634 if (CPU_ABSENT(cpu)) 635 continue; 636 cache = &zone->uz_cpu[cpu]; 637 bucket_drain(zone, cache->uc_allocbucket); 638 bucket_drain(zone, cache->uc_freebucket); 639 if (cache->uc_allocbucket != NULL) 640 bucket_free(cache->uc_allocbucket); 641 if (cache->uc_freebucket != NULL) 642 bucket_free(cache->uc_freebucket); 643 cache->uc_allocbucket = cache->uc_freebucket = NULL; 644 } 645 ZONE_LOCK(zone); 646 bucket_cache_drain(zone); 647 ZONE_UNLOCK(zone); 648 } 649 650 /* 651 * Drain the cached buckets from a zone. Expects a locked zone on entry. 652 */ 653 static void 654 bucket_cache_drain(uma_zone_t zone) 655 { 656 uma_bucket_t bucket; 657 658 /* 659 * Drain the bucket queues and free the buckets, we just keep two per 660 * cpu (alloc/free). 661 */ 662 while ((bucket = LIST_FIRST(&zone->uz_full_bucket)) != NULL) { 663 LIST_REMOVE(bucket, ub_link); 664 ZONE_UNLOCK(zone); 665 bucket_drain(zone, bucket); 666 bucket_free(bucket); 667 ZONE_LOCK(zone); 668 } 669 670 /* Now we do the free queue.. */ 671 while ((bucket = LIST_FIRST(&zone->uz_free_bucket)) != NULL) { 672 LIST_REMOVE(bucket, ub_link); 673 bucket_free(bucket); 674 } 675 } 676 677 /* 678 * Frees pages from a zone back to the system. This is done on demand from 679 * the pageout daemon. 680 * 681 * Arguments: 682 * zone The zone to free pages from 683 * all Should we drain all items? 684 * 685 * Returns: 686 * Nothing. 687 */ 688 static void 689 zone_drain(uma_zone_t zone) 690 { 691 struct slabhead freeslabs = { 0 }; 692 uma_keg_t keg; 693 uma_slab_t slab; 694 uma_slab_t n; 695 u_int8_t flags; 696 u_int8_t *mem; 697 int i; 698 699 keg = zone->uz_keg; 700 701 /* 702 * We don't want to take pages from statically allocated zones at this 703 * time 704 */ 705 if (keg->uk_flags & UMA_ZONE_NOFREE || keg->uk_freef == NULL) 706 return; 707 708 ZONE_LOCK(zone); 709 710 #ifdef UMA_DEBUG 711 printf("%s free items: %u\n", zone->uz_name, keg->uk_free); 712 #endif 713 bucket_cache_drain(zone); 714 if (keg->uk_free == 0) 715 goto finished; 716 717 slab = LIST_FIRST(&keg->uk_free_slab); 718 while (slab) { 719 n = LIST_NEXT(slab, us_link); 720 721 /* We have no where to free these to */ 722 if (slab->us_flags & UMA_SLAB_BOOT) { 723 slab = n; 724 continue; 725 } 726 727 LIST_REMOVE(slab, us_link); 728 keg->uk_pages -= keg->uk_ppera; 729 keg->uk_free -= keg->uk_ipers; 730 731 if (keg->uk_flags & UMA_ZONE_HASH) 732 UMA_HASH_REMOVE(&keg->uk_hash, slab, slab->us_data); 733 734 SLIST_INSERT_HEAD(&freeslabs, slab, us_hlink); 735 736 slab = n; 737 } 738 finished: 739 ZONE_UNLOCK(zone); 740 741 while ((slab = SLIST_FIRST(&freeslabs)) != NULL) { 742 SLIST_REMOVE(&freeslabs, slab, uma_slab, us_hlink); 743 if (keg->uk_fini) 744 for (i = 0; i < keg->uk_ipers; i++) 745 keg->uk_fini( 746 slab->us_data + (keg->uk_rsize * i), 747 keg->uk_size); 748 flags = slab->us_flags; 749 mem = slab->us_data; 750 751 if ((keg->uk_flags & UMA_ZONE_MALLOC) || 752 (keg->uk_flags & UMA_ZONE_REFCNT)) { 753 vm_object_t obj; 754 755 if (flags & UMA_SLAB_KMEM) 756 obj = kmem_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 uma_zfree_internal(keg->uk_slabzone, slab, NULL, 765 SKIP_NONE, ZFREE_STATFREE); 766 #ifdef UMA_DEBUG 767 printf("%s: Returning %d bytes.\n", 768 zone->uz_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 /* 775 * Allocate a new slab for a zone. This does not insert the slab onto a list. 776 * 777 * Arguments: 778 * zone The zone to allocate slabs for 779 * wait Shall we wait? 780 * 781 * Returns: 782 * The slab that was allocated or NULL if there is no memory and the 783 * caller specified M_NOWAIT. 784 */ 785 static uma_slab_t 786 slab_zalloc(uma_zone_t zone, int wait) 787 { 788 uma_slabrefcnt_t slabref; 789 uma_slab_t slab; 790 uma_keg_t keg; 791 u_int8_t *mem; 792 u_int8_t flags; 793 int i; 794 795 slab = NULL; 796 keg = zone->uz_keg; 797 798 #ifdef UMA_DEBUG 799 printf("slab_zalloc: Allocating a new slab for %s\n", zone->uz_name); 800 #endif 801 ZONE_UNLOCK(zone); 802 803 if (keg->uk_flags & UMA_ZONE_OFFPAGE) { 804 slab = uma_zalloc_internal(keg->uk_slabzone, NULL, wait); 805 if (slab == NULL) { 806 ZONE_LOCK(zone); 807 return NULL; 808 } 809 } 810 811 /* 812 * This reproduces the old vm_zone behavior of zero filling pages the 813 * first time they are added to a zone. 814 * 815 * Malloced items are zeroed in uma_zalloc. 816 */ 817 818 if ((keg->uk_flags & UMA_ZONE_MALLOC) == 0) 819 wait |= M_ZERO; 820 else 821 wait &= ~M_ZERO; 822 823 mem = keg->uk_allocf(zone, keg->uk_ppera * UMA_SLAB_SIZE, 824 &flags, wait); 825 if (mem == NULL) { 826 if (keg->uk_flags & UMA_ZONE_OFFPAGE) 827 uma_zfree_internal(keg->uk_slabzone, slab, NULL, 828 SKIP_NONE, ZFREE_STATFREE); 829 ZONE_LOCK(zone); 830 return (NULL); 831 } 832 833 /* Point the slab into the allocated memory */ 834 if (!(keg->uk_flags & UMA_ZONE_OFFPAGE)) 835 slab = (uma_slab_t )(mem + keg->uk_pgoff); 836 837 if ((keg->uk_flags & UMA_ZONE_MALLOC) || 838 (keg->uk_flags & UMA_ZONE_REFCNT)) 839 for (i = 0; i < keg->uk_ppera; i++) 840 vsetslab((vm_offset_t)mem + (i * PAGE_SIZE), slab); 841 842 slab->us_keg = keg; 843 slab->us_data = mem; 844 slab->us_freecount = keg->uk_ipers; 845 slab->us_firstfree = 0; 846 slab->us_flags = flags; 847 848 if (keg->uk_flags & UMA_ZONE_REFCNT) { 849 slabref = (uma_slabrefcnt_t)slab; 850 for (i = 0; i < keg->uk_ipers; i++) { 851 slabref->us_freelist[i].us_refcnt = 0; 852 slabref->us_freelist[i].us_item = i+1; 853 } 854 } else { 855 for (i = 0; i < keg->uk_ipers; i++) 856 slab->us_freelist[i].us_item = i+1; 857 } 858 859 if (keg->uk_init != NULL) { 860 for (i = 0; i < keg->uk_ipers; i++) 861 if (keg->uk_init(slab->us_data + (keg->uk_rsize * i), 862 keg->uk_size, wait) != 0) 863 break; 864 if (i != keg->uk_ipers) { 865 if (keg->uk_fini != NULL) { 866 for (i--; i > -1; i--) 867 keg->uk_fini(slab->us_data + 868 (keg->uk_rsize * i), 869 keg->uk_size); 870 } 871 if ((keg->uk_flags & UMA_ZONE_MALLOC) || 872 (keg->uk_flags & UMA_ZONE_REFCNT)) { 873 vm_object_t obj; 874 875 if (flags & UMA_SLAB_KMEM) 876 obj = kmem_object; 877 else 878 obj = NULL; 879 for (i = 0; i < keg->uk_ppera; i++) 880 vsetobj((vm_offset_t)mem + 881 (i * PAGE_SIZE), obj); 882 } 883 if (keg->uk_flags & UMA_ZONE_OFFPAGE) 884 uma_zfree_internal(keg->uk_slabzone, slab, 885 NULL, SKIP_NONE, ZFREE_STATFREE); 886 keg->uk_freef(mem, UMA_SLAB_SIZE * keg->uk_ppera, 887 flags); 888 ZONE_LOCK(zone); 889 return (NULL); 890 } 891 } 892 ZONE_LOCK(zone); 893 894 if (keg->uk_flags & UMA_ZONE_HASH) 895 UMA_HASH_INSERT(&keg->uk_hash, slab, mem); 896 897 keg->uk_pages += keg->uk_ppera; 898 keg->uk_free += keg->uk_ipers; 899 900 return (slab); 901 } 902 903 /* 904 * This function is intended to be used early on in place of page_alloc() so 905 * that we may use the boot time page cache to satisfy allocations before 906 * the VM is ready. 907 */ 908 static void * 909 startup_alloc(uma_zone_t zone, int bytes, u_int8_t *pflag, int wait) 910 { 911 uma_keg_t keg; 912 uma_slab_t tmps; 913 914 keg = zone->uz_keg; 915 916 /* 917 * Check our small startup cache to see if it has pages remaining. 918 */ 919 mtx_lock(&uma_boot_pages_mtx); 920 if ((tmps = LIST_FIRST(&uma_boot_pages)) != NULL) { 921 LIST_REMOVE(tmps, us_link); 922 mtx_unlock(&uma_boot_pages_mtx); 923 *pflag = tmps->us_flags; 924 return (tmps->us_data); 925 } 926 mtx_unlock(&uma_boot_pages_mtx); 927 if (booted == 0) 928 panic("UMA: Increase vm.boot_pages"); 929 /* 930 * Now that we've booted reset these users to their real allocator. 931 */ 932 #ifdef UMA_MD_SMALL_ALLOC 933 keg->uk_allocf = uma_small_alloc; 934 #else 935 keg->uk_allocf = page_alloc; 936 #endif 937 return keg->uk_allocf(zone, bytes, pflag, wait); 938 } 939 940 /* 941 * Allocates a number of pages from the system 942 * 943 * Arguments: 944 * zone Unused 945 * bytes The number of bytes requested 946 * wait Shall we wait? 947 * 948 * Returns: 949 * A pointer to the alloced memory or possibly 950 * NULL if M_NOWAIT is set. 951 */ 952 static void * 953 page_alloc(uma_zone_t zone, int bytes, u_int8_t *pflag, int wait) 954 { 955 void *p; /* Returned page */ 956 957 *pflag = UMA_SLAB_KMEM; 958 p = (void *) kmem_malloc(kmem_map, bytes, wait); 959 960 return (p); 961 } 962 963 /* 964 * Allocates a number of pages from within an object 965 * 966 * Arguments: 967 * zone Unused 968 * bytes The number of bytes requested 969 * wait Shall we wait? 970 * 971 * Returns: 972 * A pointer to the alloced memory or possibly 973 * NULL if M_NOWAIT is set. 974 */ 975 static void * 976 obj_alloc(uma_zone_t zone, int bytes, u_int8_t *flags, int wait) 977 { 978 vm_object_t object; 979 vm_offset_t retkva, zkva; 980 vm_page_t p; 981 int pages, startpages; 982 983 object = zone->uz_keg->uk_obj; 984 retkva = 0; 985 986 /* 987 * This looks a little weird since we're getting one page at a time. 988 */ 989 VM_OBJECT_LOCK(object); 990 p = TAILQ_LAST(&object->memq, pglist); 991 pages = p != NULL ? p->pindex + 1 : 0; 992 startpages = pages; 993 zkva = zone->uz_keg->uk_kva + pages * PAGE_SIZE; 994 for (; bytes > 0; bytes -= PAGE_SIZE) { 995 p = vm_page_alloc(object, pages, 996 VM_ALLOC_INTERRUPT | VM_ALLOC_WIRED); 997 if (p == NULL) { 998 if (pages != startpages) 999 pmap_qremove(retkva, pages - startpages); 1000 while (pages != startpages) { 1001 pages--; 1002 p = TAILQ_LAST(&object->memq, pglist); 1003 vm_page_lock_queues(); 1004 vm_page_unwire(p, 0); 1005 vm_page_free(p); 1006 vm_page_unlock_queues(); 1007 } 1008 retkva = 0; 1009 goto done; 1010 } 1011 pmap_qenter(zkva, &p, 1); 1012 if (retkva == 0) 1013 retkva = zkva; 1014 zkva += PAGE_SIZE; 1015 pages += 1; 1016 } 1017 done: 1018 VM_OBJECT_UNLOCK(object); 1019 *flags = UMA_SLAB_PRIV; 1020 1021 return ((void *)retkva); 1022 } 1023 1024 /* 1025 * Frees a number of pages to the system 1026 * 1027 * Arguments: 1028 * mem A pointer to the memory to be freed 1029 * size The size of the memory being freed 1030 * flags The original p->us_flags field 1031 * 1032 * Returns: 1033 * Nothing 1034 */ 1035 static void 1036 page_free(void *mem, int size, u_int8_t flags) 1037 { 1038 vm_map_t map; 1039 1040 if (flags & UMA_SLAB_KMEM) 1041 map = kmem_map; 1042 else 1043 panic("UMA: page_free used with invalid flags %d\n", flags); 1044 1045 kmem_free(map, (vm_offset_t)mem, size); 1046 } 1047 1048 /* 1049 * Zero fill initializer 1050 * 1051 * Arguments/Returns follow uma_init specifications 1052 */ 1053 static int 1054 zero_init(void *mem, int size, int flags) 1055 { 1056 bzero(mem, size); 1057 return (0); 1058 } 1059 1060 /* 1061 * Finish creating a small uma zone. This calculates ipers, and the zone size. 1062 * 1063 * Arguments 1064 * zone The zone we should initialize 1065 * 1066 * Returns 1067 * Nothing 1068 */ 1069 static void 1070 zone_small_init(uma_zone_t zone) 1071 { 1072 uma_keg_t keg; 1073 u_int rsize; 1074 u_int memused; 1075 u_int wastedspace; 1076 u_int shsize; 1077 1078 keg = zone->uz_keg; 1079 KASSERT(keg != NULL, ("Keg is null in zone_small_init")); 1080 rsize = keg->uk_size; 1081 1082 if (rsize < UMA_SMALLEST_UNIT) 1083 rsize = UMA_SMALLEST_UNIT; 1084 if (rsize & keg->uk_align) 1085 rsize = (rsize & ~keg->uk_align) + (keg->uk_align + 1); 1086 1087 keg->uk_rsize = rsize; 1088 keg->uk_ppera = 1; 1089 1090 if (keg->uk_flags & UMA_ZONE_REFCNT) { 1091 rsize += UMA_FRITMREF_SZ; /* linkage & refcnt */ 1092 shsize = sizeof(struct uma_slab_refcnt); 1093 } else { 1094 rsize += UMA_FRITM_SZ; /* Account for linkage */ 1095 shsize = sizeof(struct uma_slab); 1096 } 1097 1098 keg->uk_ipers = (UMA_SLAB_SIZE - shsize) / rsize; 1099 KASSERT(keg->uk_ipers != 0, ("zone_small_init: ipers is 0")); 1100 memused = keg->uk_ipers * rsize + shsize; 1101 wastedspace = UMA_SLAB_SIZE - memused; 1102 1103 /* 1104 * We can't do OFFPAGE if we're internal or if we've been 1105 * asked to not go to the VM for buckets. If we do this we 1106 * may end up going to the VM (kmem_map) for slabs which we 1107 * do not want to do if we're UMA_ZFLAG_CACHEONLY as a 1108 * result of UMA_ZONE_VM, which clearly forbids it. 1109 */ 1110 if ((keg->uk_flags & UMA_ZFLAG_INTERNAL) || 1111 (keg->uk_flags & UMA_ZFLAG_CACHEONLY)) 1112 return; 1113 1114 if ((wastedspace >= UMA_MAX_WASTE) && 1115 (keg->uk_ipers < (UMA_SLAB_SIZE / keg->uk_rsize))) { 1116 keg->uk_ipers = UMA_SLAB_SIZE / keg->uk_rsize; 1117 KASSERT(keg->uk_ipers <= 255, 1118 ("zone_small_init: keg->uk_ipers too high!")); 1119 #ifdef UMA_DEBUG 1120 printf("UMA decided we need offpage slab headers for " 1121 "zone: %s, calculated wastedspace = %d, " 1122 "maximum wasted space allowed = %d, " 1123 "calculated ipers = %d, " 1124 "new wasted space = %d\n", zone->uz_name, wastedspace, 1125 UMA_MAX_WASTE, keg->uk_ipers, 1126 UMA_SLAB_SIZE - keg->uk_ipers * keg->uk_rsize); 1127 #endif 1128 keg->uk_flags |= UMA_ZONE_OFFPAGE; 1129 if ((keg->uk_flags & UMA_ZONE_MALLOC) == 0) 1130 keg->uk_flags |= UMA_ZONE_HASH; 1131 } 1132 } 1133 1134 /* 1135 * Finish creating a large (> UMA_SLAB_SIZE) uma zone. Just give in and do 1136 * OFFPAGE for now. When I can allow for more dynamic slab sizes this will be 1137 * more complicated. 1138 * 1139 * Arguments 1140 * zone The zone we should initialize 1141 * 1142 * Returns 1143 * Nothing 1144 */ 1145 static void 1146 zone_large_init(uma_zone_t zone) 1147 { 1148 uma_keg_t keg; 1149 int pages; 1150 1151 keg = zone->uz_keg; 1152 1153 KASSERT(keg != NULL, ("Keg is null in zone_large_init")); 1154 KASSERT((keg->uk_flags & UMA_ZFLAG_CACHEONLY) == 0, 1155 ("zone_large_init: Cannot large-init a UMA_ZFLAG_CACHEONLY zone")); 1156 1157 pages = keg->uk_size / UMA_SLAB_SIZE; 1158 1159 /* Account for remainder */ 1160 if ((pages * UMA_SLAB_SIZE) < keg->uk_size) 1161 pages++; 1162 1163 keg->uk_ppera = pages; 1164 keg->uk_ipers = 1; 1165 1166 keg->uk_flags |= UMA_ZONE_OFFPAGE; 1167 if ((keg->uk_flags & UMA_ZONE_MALLOC) == 0) 1168 keg->uk_flags |= UMA_ZONE_HASH; 1169 1170 keg->uk_rsize = keg->uk_size; 1171 } 1172 1173 /* 1174 * Keg header ctor. This initializes all fields, locks, etc. And inserts 1175 * the keg onto the global keg list. 1176 * 1177 * Arguments/Returns follow uma_ctor specifications 1178 * udata Actually uma_kctor_args 1179 */ 1180 static int 1181 keg_ctor(void *mem, int size, void *udata, int flags) 1182 { 1183 struct uma_kctor_args *arg = udata; 1184 uma_keg_t keg = mem; 1185 uma_zone_t zone; 1186 1187 bzero(keg, size); 1188 keg->uk_size = arg->size; 1189 keg->uk_init = arg->uminit; 1190 keg->uk_fini = arg->fini; 1191 keg->uk_align = arg->align; 1192 keg->uk_free = 0; 1193 keg->uk_pages = 0; 1194 keg->uk_flags = arg->flags; 1195 keg->uk_allocf = page_alloc; 1196 keg->uk_freef = page_free; 1197 keg->uk_recurse = 0; 1198 keg->uk_slabzone = NULL; 1199 1200 /* 1201 * The master zone is passed to us at keg-creation time. 1202 */ 1203 zone = arg->zone; 1204 zone->uz_keg = keg; 1205 1206 if (arg->flags & UMA_ZONE_VM) 1207 keg->uk_flags |= UMA_ZFLAG_CACHEONLY; 1208 1209 if (arg->flags & UMA_ZONE_ZINIT) 1210 keg->uk_init = zero_init; 1211 1212 /* 1213 * The +UMA_FRITM_SZ added to uk_size is to account for the 1214 * linkage that is added to the size in zone_small_init(). If 1215 * we don't account for this here then we may end up in 1216 * zone_small_init() with a calculated 'ipers' of 0. 1217 */ 1218 if (keg->uk_flags & UMA_ZONE_REFCNT) { 1219 if ((keg->uk_size+UMA_FRITMREF_SZ) > 1220 (UMA_SLAB_SIZE - sizeof(struct uma_slab_refcnt))) 1221 zone_large_init(zone); 1222 else 1223 zone_small_init(zone); 1224 } else { 1225 if ((keg->uk_size+UMA_FRITM_SZ) > 1226 (UMA_SLAB_SIZE - sizeof(struct uma_slab))) 1227 zone_large_init(zone); 1228 else 1229 zone_small_init(zone); 1230 } 1231 1232 if (keg->uk_flags & UMA_ZONE_OFFPAGE) { 1233 if (keg->uk_flags & UMA_ZONE_REFCNT) 1234 keg->uk_slabzone = slabrefzone; 1235 else 1236 keg->uk_slabzone = slabzone; 1237 } 1238 1239 /* 1240 * If we haven't booted yet we need allocations to go through the 1241 * startup cache until the vm is ready. 1242 */ 1243 if (keg->uk_ppera == 1) { 1244 #ifdef UMA_MD_SMALL_ALLOC 1245 keg->uk_allocf = uma_small_alloc; 1246 keg->uk_freef = uma_small_free; 1247 #endif 1248 if (booted == 0) 1249 keg->uk_allocf = startup_alloc; 1250 } 1251 1252 /* 1253 * Initialize keg's lock (shared among zones) through 1254 * Master zone 1255 */ 1256 zone->uz_lock = &keg->uk_lock; 1257 if (arg->flags & UMA_ZONE_MTXCLASS) 1258 ZONE_LOCK_INIT(zone, 1); 1259 else 1260 ZONE_LOCK_INIT(zone, 0); 1261 1262 /* 1263 * If we're putting the slab header in the actual page we need to 1264 * figure out where in each page it goes. This calculates a right 1265 * justified offset into the memory on an ALIGN_PTR boundary. 1266 */ 1267 if (!(keg->uk_flags & UMA_ZONE_OFFPAGE)) { 1268 u_int totsize; 1269 1270 /* Size of the slab struct and free list */ 1271 if (keg->uk_flags & UMA_ZONE_REFCNT) 1272 totsize = sizeof(struct uma_slab_refcnt) + 1273 keg->uk_ipers * UMA_FRITMREF_SZ; 1274 else 1275 totsize = sizeof(struct uma_slab) + 1276 keg->uk_ipers * UMA_FRITM_SZ; 1277 1278 if (totsize & UMA_ALIGN_PTR) 1279 totsize = (totsize & ~UMA_ALIGN_PTR) + 1280 (UMA_ALIGN_PTR + 1); 1281 keg->uk_pgoff = UMA_SLAB_SIZE - totsize; 1282 1283 if (keg->uk_flags & UMA_ZONE_REFCNT) 1284 totsize = keg->uk_pgoff + sizeof(struct uma_slab_refcnt) 1285 + keg->uk_ipers * UMA_FRITMREF_SZ; 1286 else 1287 totsize = keg->uk_pgoff + sizeof(struct uma_slab) 1288 + keg->uk_ipers * UMA_FRITM_SZ; 1289 1290 /* 1291 * The only way the following is possible is if with our 1292 * UMA_ALIGN_PTR adjustments we are now bigger than 1293 * UMA_SLAB_SIZE. I haven't checked whether this is 1294 * mathematically possible for all cases, so we make 1295 * sure here anyway. 1296 */ 1297 if (totsize > UMA_SLAB_SIZE) { 1298 printf("zone %s ipers %d rsize %d size %d\n", 1299 zone->uz_name, keg->uk_ipers, keg->uk_rsize, 1300 keg->uk_size); 1301 panic("UMA slab won't fit.\n"); 1302 } 1303 } 1304 1305 if (keg->uk_flags & UMA_ZONE_HASH) 1306 hash_alloc(&keg->uk_hash); 1307 1308 #ifdef UMA_DEBUG 1309 printf("%s(%p) size = %d ipers = %d ppera = %d pgoff = %d\n", 1310 zone->uz_name, zone, 1311 keg->uk_size, keg->uk_ipers, 1312 keg->uk_ppera, keg->uk_pgoff); 1313 #endif 1314 1315 LIST_INSERT_HEAD(&keg->uk_zones, zone, uz_link); 1316 1317 mtx_lock(&uma_mtx); 1318 LIST_INSERT_HEAD(&uma_kegs, keg, uk_link); 1319 mtx_unlock(&uma_mtx); 1320 return (0); 1321 } 1322 1323 /* 1324 * Zone header ctor. This initializes all fields, locks, etc. 1325 * 1326 * Arguments/Returns follow uma_ctor specifications 1327 * udata Actually uma_zctor_args 1328 */ 1329 1330 static int 1331 zone_ctor(void *mem, int size, void *udata, int flags) 1332 { 1333 struct uma_zctor_args *arg = udata; 1334 uma_zone_t zone = mem; 1335 uma_zone_t z; 1336 uma_keg_t keg; 1337 1338 bzero(zone, size); 1339 zone->uz_name = arg->name; 1340 zone->uz_ctor = arg->ctor; 1341 zone->uz_dtor = arg->dtor; 1342 zone->uz_init = NULL; 1343 zone->uz_fini = NULL; 1344 zone->uz_allocs = 0; 1345 zone->uz_frees = 0; 1346 zone->uz_fails = 0; 1347 zone->uz_fills = zone->uz_count = 0; 1348 1349 if (arg->flags & UMA_ZONE_SECONDARY) { 1350 KASSERT(arg->keg != NULL, ("Secondary zone on zero'd keg")); 1351 keg = arg->keg; 1352 zone->uz_keg = keg; 1353 zone->uz_init = arg->uminit; 1354 zone->uz_fini = arg->fini; 1355 zone->uz_lock = &keg->uk_lock; 1356 mtx_lock(&uma_mtx); 1357 ZONE_LOCK(zone); 1358 keg->uk_flags |= UMA_ZONE_SECONDARY; 1359 LIST_FOREACH(z, &keg->uk_zones, uz_link) { 1360 if (LIST_NEXT(z, uz_link) == NULL) { 1361 LIST_INSERT_AFTER(z, zone, uz_link); 1362 break; 1363 } 1364 } 1365 ZONE_UNLOCK(zone); 1366 mtx_unlock(&uma_mtx); 1367 } else if (arg->keg == NULL) { 1368 if (uma_kcreate(zone, arg->size, arg->uminit, arg->fini, 1369 arg->align, arg->flags) == NULL) 1370 return (ENOMEM); 1371 } else { 1372 struct uma_kctor_args karg; 1373 int error; 1374 1375 /* We should only be here from uma_startup() */ 1376 karg.size = arg->size; 1377 karg.uminit = arg->uminit; 1378 karg.fini = arg->fini; 1379 karg.align = arg->align; 1380 karg.flags = arg->flags; 1381 karg.zone = zone; 1382 error = keg_ctor(arg->keg, sizeof(struct uma_keg), &karg, 1383 flags); 1384 if (error) 1385 return (error); 1386 } 1387 keg = zone->uz_keg; 1388 zone->uz_lock = &keg->uk_lock; 1389 1390 /* 1391 * Some internal zones don't have room allocated for the per cpu 1392 * caches. If we're internal, bail out here. 1393 */ 1394 if (keg->uk_flags & UMA_ZFLAG_INTERNAL) { 1395 KASSERT((keg->uk_flags & UMA_ZONE_SECONDARY) == 0, 1396 ("Secondary zone requested UMA_ZFLAG_INTERNAL")); 1397 return (0); 1398 } 1399 1400 if (keg->uk_flags & UMA_ZONE_MAXBUCKET) 1401 zone->uz_count = BUCKET_MAX; 1402 else if (keg->uk_ipers <= BUCKET_MAX) 1403 zone->uz_count = keg->uk_ipers; 1404 else 1405 zone->uz_count = BUCKET_MAX; 1406 return (0); 1407 } 1408 1409 /* 1410 * Keg header dtor. This frees all data, destroys locks, frees the hash 1411 * table and removes the keg from the global list. 1412 * 1413 * Arguments/Returns follow uma_dtor specifications 1414 * udata unused 1415 */ 1416 static void 1417 keg_dtor(void *arg, int size, void *udata) 1418 { 1419 uma_keg_t keg; 1420 1421 keg = (uma_keg_t)arg; 1422 mtx_lock(&keg->uk_lock); 1423 if (keg->uk_free != 0) { 1424 printf("Freed UMA keg was not empty (%d items). " 1425 " Lost %d pages of memory.\n", 1426 keg->uk_free, keg->uk_pages); 1427 } 1428 mtx_unlock(&keg->uk_lock); 1429 1430 if (keg->uk_flags & UMA_ZONE_HASH) 1431 hash_free(&keg->uk_hash); 1432 1433 mtx_destroy(&keg->uk_lock); 1434 } 1435 1436 /* 1437 * Zone header dtor. 1438 * 1439 * Arguments/Returns follow uma_dtor specifications 1440 * udata unused 1441 */ 1442 static void 1443 zone_dtor(void *arg, int size, void *udata) 1444 { 1445 uma_zone_t zone; 1446 uma_keg_t keg; 1447 1448 zone = (uma_zone_t)arg; 1449 keg = zone->uz_keg; 1450 1451 if (!(keg->uk_flags & UMA_ZFLAG_INTERNAL)) 1452 cache_drain(zone); 1453 1454 mtx_lock(&uma_mtx); 1455 zone_drain(zone); 1456 if (keg->uk_flags & UMA_ZONE_SECONDARY) { 1457 LIST_REMOVE(zone, uz_link); 1458 /* 1459 * XXX there are some races here where 1460 * the zone can be drained but zone lock 1461 * released and then refilled before we 1462 * remove it... we dont care for now 1463 */ 1464 ZONE_LOCK(zone); 1465 if (LIST_EMPTY(&keg->uk_zones)) 1466 keg->uk_flags &= ~UMA_ZONE_SECONDARY; 1467 ZONE_UNLOCK(zone); 1468 mtx_unlock(&uma_mtx); 1469 } else { 1470 LIST_REMOVE(keg, uk_link); 1471 LIST_REMOVE(zone, uz_link); 1472 mtx_unlock(&uma_mtx); 1473 uma_zfree_internal(kegs, keg, NULL, SKIP_NONE, 1474 ZFREE_STATFREE); 1475 } 1476 zone->uz_keg = NULL; 1477 } 1478 1479 /* 1480 * Traverses every zone in the system and calls a callback 1481 * 1482 * Arguments: 1483 * zfunc A pointer to a function which accepts a zone 1484 * as an argument. 1485 * 1486 * Returns: 1487 * Nothing 1488 */ 1489 static void 1490 zone_foreach(void (*zfunc)(uma_zone_t)) 1491 { 1492 uma_keg_t keg; 1493 uma_zone_t zone; 1494 1495 mtx_lock(&uma_mtx); 1496 LIST_FOREACH(keg, &uma_kegs, uk_link) { 1497 LIST_FOREACH(zone, &keg->uk_zones, uz_link) 1498 zfunc(zone); 1499 } 1500 mtx_unlock(&uma_mtx); 1501 } 1502 1503 /* Public functions */ 1504 /* See uma.h */ 1505 void 1506 uma_startup(void *bootmem, int boot_pages) 1507 { 1508 struct uma_zctor_args args; 1509 uma_slab_t slab; 1510 u_int slabsize; 1511 u_int objsize, totsize, wsize; 1512 int i; 1513 1514 #ifdef UMA_DEBUG 1515 printf("Creating uma keg headers zone and keg.\n"); 1516 #endif 1517 mtx_init(&uma_mtx, "UMA lock", NULL, MTX_DEF); 1518 1519 /* 1520 * Figure out the maximum number of items-per-slab we'll have if 1521 * we're using the OFFPAGE slab header to track free items, given 1522 * all possible object sizes and the maximum desired wastage 1523 * (UMA_MAX_WASTE). 1524 * 1525 * We iterate until we find an object size for 1526 * which the calculated wastage in zone_small_init() will be 1527 * enough to warrant OFFPAGE. Since wastedspace versus objsize 1528 * is an overall increasing see-saw function, we find the smallest 1529 * objsize such that the wastage is always acceptable for objects 1530 * with that objsize or smaller. Since a smaller objsize always 1531 * generates a larger possible uma_max_ipers, we use this computed 1532 * objsize to calculate the largest ipers possible. Since the 1533 * ipers calculated for OFFPAGE slab headers is always larger than 1534 * the ipers initially calculated in zone_small_init(), we use 1535 * the former's equation (UMA_SLAB_SIZE / keg->uk_rsize) to 1536 * obtain the maximum ipers possible for offpage slab headers. 1537 * 1538 * It should be noted that ipers versus objsize is an inversly 1539 * proportional function which drops off rather quickly so as 1540 * long as our UMA_MAX_WASTE is such that the objsize we calculate 1541 * falls into the portion of the inverse relation AFTER the steep 1542 * falloff, then uma_max_ipers shouldn't be too high (~10 on i386). 1543 * 1544 * Note that we have 8-bits (1 byte) to use as a freelist index 1545 * inside the actual slab header itself and this is enough to 1546 * accomodate us. In the worst case, a UMA_SMALLEST_UNIT sized 1547 * object with offpage slab header would have ipers = 1548 * UMA_SLAB_SIZE / UMA_SMALLEST_UNIT (currently = 256), which is 1549 * 1 greater than what our byte-integer freelist index can 1550 * accomodate, but we know that this situation never occurs as 1551 * for UMA_SMALLEST_UNIT-sized objects, we will never calculate 1552 * that we need to go to offpage slab headers. Or, if we do, 1553 * then we trap that condition below and panic in the INVARIANTS case. 1554 */ 1555 wsize = UMA_SLAB_SIZE - sizeof(struct uma_slab) - UMA_MAX_WASTE; 1556 totsize = wsize; 1557 objsize = UMA_SMALLEST_UNIT; 1558 while (totsize >= wsize) { 1559 totsize = (UMA_SLAB_SIZE - sizeof(struct uma_slab)) / 1560 (objsize + UMA_FRITM_SZ); 1561 totsize *= (UMA_FRITM_SZ + objsize); 1562 objsize++; 1563 } 1564 if (objsize > UMA_SMALLEST_UNIT) 1565 objsize--; 1566 uma_max_ipers = UMA_SLAB_SIZE / objsize; 1567 1568 wsize = UMA_SLAB_SIZE - sizeof(struct uma_slab_refcnt) - UMA_MAX_WASTE; 1569 totsize = wsize; 1570 objsize = UMA_SMALLEST_UNIT; 1571 while (totsize >= wsize) { 1572 totsize = (UMA_SLAB_SIZE - sizeof(struct uma_slab_refcnt)) / 1573 (objsize + UMA_FRITMREF_SZ); 1574 totsize *= (UMA_FRITMREF_SZ + objsize); 1575 objsize++; 1576 } 1577 if (objsize > UMA_SMALLEST_UNIT) 1578 objsize--; 1579 uma_max_ipers_ref = UMA_SLAB_SIZE / objsize; 1580 1581 KASSERT((uma_max_ipers_ref <= 255) && (uma_max_ipers <= 255), 1582 ("uma_startup: calculated uma_max_ipers values too large!")); 1583 1584 #ifdef UMA_DEBUG 1585 printf("Calculated uma_max_ipers (for OFFPAGE) is %d\n", uma_max_ipers); 1586 printf("Calculated uma_max_ipers_slab (for OFFPAGE) is %d\n", 1587 uma_max_ipers_ref); 1588 #endif 1589 1590 /* "manually" create the initial zone */ 1591 args.name = "UMA Kegs"; 1592 args.size = sizeof(struct uma_keg); 1593 args.ctor = keg_ctor; 1594 args.dtor = keg_dtor; 1595 args.uminit = zero_init; 1596 args.fini = NULL; 1597 args.keg = &masterkeg; 1598 args.align = 32 - 1; 1599 args.flags = UMA_ZFLAG_INTERNAL; 1600 /* The initial zone has no Per cpu queues so it's smaller */ 1601 zone_ctor(kegs, sizeof(struct uma_zone), &args, M_WAITOK); 1602 1603 #ifdef UMA_DEBUG 1604 printf("Filling boot free list.\n"); 1605 #endif 1606 for (i = 0; i < boot_pages; i++) { 1607 slab = (uma_slab_t)((u_int8_t *)bootmem + (i * UMA_SLAB_SIZE)); 1608 slab->us_data = (u_int8_t *)slab; 1609 slab->us_flags = UMA_SLAB_BOOT; 1610 LIST_INSERT_HEAD(&uma_boot_pages, slab, us_link); 1611 } 1612 mtx_init(&uma_boot_pages_mtx, "UMA boot pages", NULL, MTX_DEF); 1613 1614 #ifdef UMA_DEBUG 1615 printf("Creating uma zone headers zone and keg.\n"); 1616 #endif 1617 args.name = "UMA Zones"; 1618 args.size = sizeof(struct uma_zone) + 1619 (sizeof(struct uma_cache) * (mp_maxid + 1)); 1620 args.ctor = zone_ctor; 1621 args.dtor = zone_dtor; 1622 args.uminit = zero_init; 1623 args.fini = NULL; 1624 args.keg = NULL; 1625 args.align = 32 - 1; 1626 args.flags = UMA_ZFLAG_INTERNAL; 1627 /* The initial zone has no Per cpu queues so it's smaller */ 1628 zone_ctor(zones, sizeof(struct uma_zone), &args, M_WAITOK); 1629 1630 #ifdef UMA_DEBUG 1631 printf("Initializing pcpu cache locks.\n"); 1632 #endif 1633 #ifdef UMA_DEBUG 1634 printf("Creating slab and hash zones.\n"); 1635 #endif 1636 1637 /* 1638 * This is the max number of free list items we'll have with 1639 * offpage slabs. 1640 */ 1641 slabsize = uma_max_ipers * UMA_FRITM_SZ; 1642 slabsize += sizeof(struct uma_slab); 1643 1644 /* Now make a zone for slab headers */ 1645 slabzone = uma_zcreate("UMA Slabs", 1646 slabsize, 1647 NULL, NULL, NULL, NULL, 1648 UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL); 1649 1650 /* 1651 * We also create a zone for the bigger slabs with reference 1652 * counts in them, to accomodate UMA_ZONE_REFCNT zones. 1653 */ 1654 slabsize = uma_max_ipers_ref * UMA_FRITMREF_SZ; 1655 slabsize += sizeof(struct uma_slab_refcnt); 1656 slabrefzone = uma_zcreate("UMA RCntSlabs", 1657 slabsize, 1658 NULL, NULL, NULL, NULL, 1659 UMA_ALIGN_PTR, 1660 UMA_ZFLAG_INTERNAL); 1661 1662 hashzone = uma_zcreate("UMA Hash", 1663 sizeof(struct slabhead *) * UMA_HASH_SIZE_INIT, 1664 NULL, NULL, NULL, NULL, 1665 UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL); 1666 1667 bucket_init(); 1668 1669 #ifdef UMA_MD_SMALL_ALLOC 1670 booted = 1; 1671 #endif 1672 1673 #ifdef UMA_DEBUG 1674 printf("UMA startup complete.\n"); 1675 #endif 1676 } 1677 1678 /* see uma.h */ 1679 void 1680 uma_startup2(void) 1681 { 1682 booted = 1; 1683 bucket_enable(); 1684 #ifdef UMA_DEBUG 1685 printf("UMA startup2 complete.\n"); 1686 #endif 1687 } 1688 1689 /* 1690 * Initialize our callout handle 1691 * 1692 */ 1693 1694 static void 1695 uma_startup3(void) 1696 { 1697 #ifdef UMA_DEBUG 1698 printf("Starting callout.\n"); 1699 #endif 1700 callout_init(&uma_callout, CALLOUT_MPSAFE); 1701 callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL); 1702 #ifdef UMA_DEBUG 1703 printf("UMA startup3 complete.\n"); 1704 #endif 1705 } 1706 1707 static uma_zone_t 1708 uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit, uma_fini fini, 1709 int align, u_int32_t flags) 1710 { 1711 struct uma_kctor_args args; 1712 1713 args.size = size; 1714 args.uminit = uminit; 1715 args.fini = fini; 1716 args.align = align; 1717 args.flags = flags; 1718 args.zone = zone; 1719 return (uma_zalloc_internal(kegs, &args, M_WAITOK)); 1720 } 1721 1722 /* See uma.h */ 1723 uma_zone_t 1724 uma_zcreate(char *name, size_t size, uma_ctor ctor, uma_dtor dtor, 1725 uma_init uminit, uma_fini fini, int align, u_int32_t flags) 1726 1727 { 1728 struct uma_zctor_args args; 1729 1730 /* This stuff is essential for the zone ctor */ 1731 args.name = name; 1732 args.size = size; 1733 args.ctor = ctor; 1734 args.dtor = dtor; 1735 args.uminit = uminit; 1736 args.fini = fini; 1737 args.align = align; 1738 args.flags = flags; 1739 args.keg = NULL; 1740 1741 return (uma_zalloc_internal(zones, &args, M_WAITOK)); 1742 } 1743 1744 /* See uma.h */ 1745 uma_zone_t 1746 uma_zsecond_create(char *name, uma_ctor ctor, uma_dtor dtor, 1747 uma_init zinit, uma_fini zfini, uma_zone_t master) 1748 { 1749 struct uma_zctor_args args; 1750 1751 args.name = name; 1752 args.size = master->uz_keg->uk_size; 1753 args.ctor = ctor; 1754 args.dtor = dtor; 1755 args.uminit = zinit; 1756 args.fini = zfini; 1757 args.align = master->uz_keg->uk_align; 1758 args.flags = master->uz_keg->uk_flags | UMA_ZONE_SECONDARY; 1759 args.keg = master->uz_keg; 1760 1761 return (uma_zalloc_internal(zones, &args, M_WAITOK)); 1762 } 1763 1764 /* See uma.h */ 1765 void 1766 uma_zdestroy(uma_zone_t zone) 1767 { 1768 1769 uma_zfree_internal(zones, zone, NULL, SKIP_NONE, ZFREE_STATFREE); 1770 } 1771 1772 /* See uma.h */ 1773 void * 1774 uma_zalloc_arg(uma_zone_t zone, void *udata, int flags) 1775 { 1776 void *item; 1777 uma_cache_t cache; 1778 uma_bucket_t bucket; 1779 int cpu; 1780 int badness; 1781 1782 /* This is the fast path allocation */ 1783 #ifdef UMA_DEBUG_ALLOC_1 1784 printf("Allocating one item from %s(%p)\n", zone->uz_name, zone); 1785 #endif 1786 CTR3(KTR_UMA, "uma_zalloc_arg thread %x zone %s flags %d", curthread, 1787 zone->uz_name, flags); 1788 1789 if (!(flags & M_NOWAIT)) { 1790 KASSERT(curthread->td_intr_nesting_level == 0, 1791 ("malloc(M_WAITOK) in interrupt context")); 1792 if (nosleepwithlocks) { 1793 #ifdef WITNESS 1794 badness = WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, 1795 NULL, 1796 "malloc(M_WAITOK) of \"%s\", forcing M_NOWAIT", 1797 zone->uz_name); 1798 #else 1799 badness = 1; 1800 #endif 1801 } else { 1802 badness = 0; 1803 #ifdef WITNESS 1804 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, 1805 "malloc(M_WAITOK) of \"%s\"", zone->uz_name); 1806 #endif 1807 } 1808 if (badness) { 1809 flags &= ~M_WAITOK; 1810 flags |= M_NOWAIT; 1811 } 1812 } 1813 1814 /* 1815 * If possible, allocate from the per-CPU cache. There are two 1816 * requirements for safe access to the per-CPU cache: (1) the thread 1817 * accessing the cache must not be preempted or yield during access, 1818 * and (2) the thread must not migrate CPUs without switching which 1819 * cache it accesses. We rely on a critical section to prevent 1820 * preemption and migration. We release the critical section in 1821 * order to acquire the zone mutex if we are unable to allocate from 1822 * the current cache; when we re-acquire the critical section, we 1823 * must detect and handle migration if it has occurred. 1824 */ 1825 zalloc_restart: 1826 critical_enter(); 1827 cpu = curcpu; 1828 cache = &zone->uz_cpu[cpu]; 1829 1830 zalloc_start: 1831 bucket = cache->uc_allocbucket; 1832 1833 if (bucket) { 1834 if (bucket->ub_cnt > 0) { 1835 bucket->ub_cnt--; 1836 item = bucket->ub_bucket[bucket->ub_cnt]; 1837 #ifdef INVARIANTS 1838 bucket->ub_bucket[bucket->ub_cnt] = NULL; 1839 #endif 1840 KASSERT(item != NULL, 1841 ("uma_zalloc: Bucket pointer mangled.")); 1842 cache->uc_allocs++; 1843 critical_exit(); 1844 #ifdef INVARIANTS 1845 ZONE_LOCK(zone); 1846 uma_dbg_alloc(zone, NULL, item); 1847 ZONE_UNLOCK(zone); 1848 #endif 1849 if (zone->uz_ctor != NULL) { 1850 if (zone->uz_ctor(item, zone->uz_keg->uk_size, 1851 udata, flags) != 0) { 1852 uma_zfree_internal(zone, item, udata, 1853 SKIP_DTOR, ZFREE_STATFAIL | 1854 ZFREE_STATFREE); 1855 return (NULL); 1856 } 1857 } 1858 if (flags & M_ZERO) 1859 bzero(item, zone->uz_keg->uk_size); 1860 return (item); 1861 } else if (cache->uc_freebucket) { 1862 /* 1863 * We have run out of items in our allocbucket. 1864 * See if we can switch with our free bucket. 1865 */ 1866 if (cache->uc_freebucket->ub_cnt > 0) { 1867 #ifdef UMA_DEBUG_ALLOC 1868 printf("uma_zalloc: Swapping empty with" 1869 " alloc.\n"); 1870 #endif 1871 bucket = cache->uc_freebucket; 1872 cache->uc_freebucket = cache->uc_allocbucket; 1873 cache->uc_allocbucket = bucket; 1874 1875 goto zalloc_start; 1876 } 1877 } 1878 } 1879 /* 1880 * Attempt to retrieve the item from the per-CPU cache has failed, so 1881 * we must go back to the zone. This requires the zone lock, so we 1882 * must drop the critical section, then re-acquire it when we go back 1883 * to the cache. Since the critical section is released, we may be 1884 * preempted or migrate. As such, make sure not to maintain any 1885 * thread-local state specific to the cache from prior to releasing 1886 * the critical section. 1887 */ 1888 critical_exit(); 1889 ZONE_LOCK(zone); 1890 critical_enter(); 1891 cpu = curcpu; 1892 cache = &zone->uz_cpu[cpu]; 1893 bucket = cache->uc_allocbucket; 1894 if (bucket != NULL) { 1895 if (bucket->ub_cnt > 0) { 1896 ZONE_UNLOCK(zone); 1897 goto zalloc_start; 1898 } 1899 bucket = cache->uc_freebucket; 1900 if (bucket != NULL && bucket->ub_cnt > 0) { 1901 ZONE_UNLOCK(zone); 1902 goto zalloc_start; 1903 } 1904 } 1905 1906 /* Since we have locked the zone we may as well send back our stats */ 1907 zone->uz_allocs += cache->uc_allocs; 1908 cache->uc_allocs = 0; 1909 zone->uz_frees += cache->uc_frees; 1910 cache->uc_frees = 0; 1911 1912 /* Our old one is now a free bucket */ 1913 if (cache->uc_allocbucket) { 1914 KASSERT(cache->uc_allocbucket->ub_cnt == 0, 1915 ("uma_zalloc_arg: Freeing a non free bucket.")); 1916 LIST_INSERT_HEAD(&zone->uz_free_bucket, 1917 cache->uc_allocbucket, ub_link); 1918 cache->uc_allocbucket = NULL; 1919 } 1920 1921 /* Check the free list for a new alloc bucket */ 1922 if ((bucket = LIST_FIRST(&zone->uz_full_bucket)) != NULL) { 1923 KASSERT(bucket->ub_cnt != 0, 1924 ("uma_zalloc_arg: Returning an empty bucket.")); 1925 1926 LIST_REMOVE(bucket, ub_link); 1927 cache->uc_allocbucket = bucket; 1928 ZONE_UNLOCK(zone); 1929 goto zalloc_start; 1930 } 1931 /* We are no longer associated with this CPU. */ 1932 critical_exit(); 1933 1934 /* Bump up our uz_count so we get here less */ 1935 if (zone->uz_count < BUCKET_MAX) 1936 zone->uz_count++; 1937 1938 /* 1939 * Now lets just fill a bucket and put it on the free list. If that 1940 * works we'll restart the allocation from the begining. 1941 */ 1942 if (uma_zalloc_bucket(zone, flags)) { 1943 ZONE_UNLOCK(zone); 1944 goto zalloc_restart; 1945 } 1946 ZONE_UNLOCK(zone); 1947 /* 1948 * We may not be able to get a bucket so return an actual item. 1949 */ 1950 #ifdef UMA_DEBUG 1951 printf("uma_zalloc_arg: Bucketzone returned NULL\n"); 1952 #endif 1953 1954 return (uma_zalloc_internal(zone, udata, flags)); 1955 } 1956 1957 static uma_slab_t 1958 uma_zone_slab(uma_zone_t zone, int flags) 1959 { 1960 uma_slab_t slab; 1961 uma_keg_t keg; 1962 1963 keg = zone->uz_keg; 1964 1965 /* 1966 * This is to prevent us from recursively trying to allocate 1967 * buckets. The problem is that if an allocation forces us to 1968 * grab a new bucket we will call page_alloc, which will go off 1969 * and cause the vm to allocate vm_map_entries. If we need new 1970 * buckets there too we will recurse in kmem_alloc and bad 1971 * things happen. So instead we return a NULL bucket, and make 1972 * the code that allocates buckets smart enough to deal with it 1973 * 1974 * XXX: While we want this protection for the bucket zones so that 1975 * recursion from the VM is handled (and the calling code that 1976 * allocates buckets knows how to deal with it), we do not want 1977 * to prevent allocation from the slab header zones (slabzone 1978 * and slabrefzone) if uk_recurse is not zero for them. The 1979 * reason is that it could lead to NULL being returned for 1980 * slab header allocations even in the M_WAITOK case, and the 1981 * caller can't handle that. 1982 */ 1983 if (keg->uk_flags & UMA_ZFLAG_INTERNAL && keg->uk_recurse != 0) 1984 if ((zone != slabzone) && (zone != slabrefzone)) 1985 return (NULL); 1986 1987 slab = NULL; 1988 1989 for (;;) { 1990 /* 1991 * Find a slab with some space. Prefer slabs that are partially 1992 * used over those that are totally full. This helps to reduce 1993 * fragmentation. 1994 */ 1995 if (keg->uk_free != 0) { 1996 if (!LIST_EMPTY(&keg->uk_part_slab)) { 1997 slab = LIST_FIRST(&keg->uk_part_slab); 1998 } else { 1999 slab = LIST_FIRST(&keg->uk_free_slab); 2000 LIST_REMOVE(slab, us_link); 2001 LIST_INSERT_HEAD(&keg->uk_part_slab, slab, 2002 us_link); 2003 } 2004 return (slab); 2005 } 2006 2007 /* 2008 * M_NOVM means don't ask at all! 2009 */ 2010 if (flags & M_NOVM) 2011 break; 2012 2013 if (keg->uk_maxpages && 2014 keg->uk_pages >= keg->uk_maxpages) { 2015 keg->uk_flags |= UMA_ZFLAG_FULL; 2016 2017 if (flags & M_NOWAIT) 2018 break; 2019 else 2020 msleep(keg, &keg->uk_lock, PVM, 2021 "zonelimit", 0); 2022 continue; 2023 } 2024 keg->uk_recurse++; 2025 slab = slab_zalloc(zone, flags); 2026 keg->uk_recurse--; 2027 2028 /* 2029 * If we got a slab here it's safe to mark it partially used 2030 * and return. We assume that the caller is going to remove 2031 * at least one item. 2032 */ 2033 if (slab) { 2034 LIST_INSERT_HEAD(&keg->uk_part_slab, slab, us_link); 2035 return (slab); 2036 } 2037 /* 2038 * We might not have been able to get a slab but another cpu 2039 * could have while we were unlocked. Check again before we 2040 * fail. 2041 */ 2042 if (flags & M_NOWAIT) 2043 flags |= M_NOVM; 2044 } 2045 return (slab); 2046 } 2047 2048 static void * 2049 uma_slab_alloc(uma_zone_t zone, uma_slab_t slab) 2050 { 2051 uma_keg_t keg; 2052 uma_slabrefcnt_t slabref; 2053 void *item; 2054 u_int8_t freei; 2055 2056 keg = zone->uz_keg; 2057 2058 freei = slab->us_firstfree; 2059 if (keg->uk_flags & UMA_ZONE_REFCNT) { 2060 slabref = (uma_slabrefcnt_t)slab; 2061 slab->us_firstfree = slabref->us_freelist[freei].us_item; 2062 } else { 2063 slab->us_firstfree = slab->us_freelist[freei].us_item; 2064 } 2065 item = slab->us_data + (keg->uk_rsize * freei); 2066 2067 slab->us_freecount--; 2068 keg->uk_free--; 2069 #ifdef INVARIANTS 2070 uma_dbg_alloc(zone, slab, item); 2071 #endif 2072 /* Move this slab to the full list */ 2073 if (slab->us_freecount == 0) { 2074 LIST_REMOVE(slab, us_link); 2075 LIST_INSERT_HEAD(&keg->uk_full_slab, slab, us_link); 2076 } 2077 2078 return (item); 2079 } 2080 2081 static int 2082 uma_zalloc_bucket(uma_zone_t zone, int flags) 2083 { 2084 uma_bucket_t bucket; 2085 uma_slab_t slab; 2086 int16_t saved; 2087 int max, origflags = flags; 2088 2089 /* 2090 * Try this zone's free list first so we don't allocate extra buckets. 2091 */ 2092 if ((bucket = LIST_FIRST(&zone->uz_free_bucket)) != NULL) { 2093 KASSERT(bucket->ub_cnt == 0, 2094 ("uma_zalloc_bucket: Bucket on free list is not empty.")); 2095 LIST_REMOVE(bucket, ub_link); 2096 } else { 2097 int bflags; 2098 2099 bflags = (flags & ~M_ZERO); 2100 if (zone->uz_keg->uk_flags & UMA_ZFLAG_CACHEONLY) 2101 bflags |= M_NOVM; 2102 2103 ZONE_UNLOCK(zone); 2104 bucket = bucket_alloc(zone->uz_count, bflags); 2105 ZONE_LOCK(zone); 2106 } 2107 2108 if (bucket == NULL) 2109 return (0); 2110 2111 #ifdef SMP 2112 /* 2113 * This code is here to limit the number of simultaneous bucket fills 2114 * for any given zone to the number of per cpu caches in this zone. This 2115 * is done so that we don't allocate more memory than we really need. 2116 */ 2117 if (zone->uz_fills >= mp_ncpus) 2118 goto done; 2119 2120 #endif 2121 zone->uz_fills++; 2122 2123 max = MIN(bucket->ub_entries, zone->uz_count); 2124 /* Try to keep the buckets totally full */ 2125 saved = bucket->ub_cnt; 2126 while (bucket->ub_cnt < max && 2127 (slab = uma_zone_slab(zone, flags)) != NULL) { 2128 while (slab->us_freecount && bucket->ub_cnt < max) { 2129 bucket->ub_bucket[bucket->ub_cnt++] = 2130 uma_slab_alloc(zone, slab); 2131 } 2132 2133 /* Don't block on the next fill */ 2134 flags |= M_NOWAIT; 2135 } 2136 2137 /* 2138 * We unlock here because we need to call the zone's init. 2139 * It should be safe to unlock because the slab dealt with 2140 * above is already on the appropriate list within the keg 2141 * and the bucket we filled is not yet on any list, so we 2142 * own it. 2143 */ 2144 if (zone->uz_init != NULL) { 2145 int i; 2146 2147 ZONE_UNLOCK(zone); 2148 for (i = saved; i < bucket->ub_cnt; i++) 2149 if (zone->uz_init(bucket->ub_bucket[i], 2150 zone->uz_keg->uk_size, origflags) != 0) 2151 break; 2152 /* 2153 * If we couldn't initialize the whole bucket, put the 2154 * rest back onto the freelist. 2155 */ 2156 if (i != bucket->ub_cnt) { 2157 int j; 2158 2159 for (j = i; j < bucket->ub_cnt; j++) { 2160 uma_zfree_internal(zone, bucket->ub_bucket[j], 2161 NULL, SKIP_FINI, 0); 2162 #ifdef INVARIANTS 2163 bucket->ub_bucket[j] = NULL; 2164 #endif 2165 } 2166 bucket->ub_cnt = i; 2167 } 2168 ZONE_LOCK(zone); 2169 } 2170 2171 zone->uz_fills--; 2172 if (bucket->ub_cnt != 0) { 2173 LIST_INSERT_HEAD(&zone->uz_full_bucket, 2174 bucket, ub_link); 2175 return (1); 2176 } 2177 #ifdef SMP 2178 done: 2179 #endif 2180 bucket_free(bucket); 2181 2182 return (0); 2183 } 2184 /* 2185 * Allocates an item for an internal zone 2186 * 2187 * Arguments 2188 * zone The zone to alloc for. 2189 * udata The data to be passed to the constructor. 2190 * flags M_WAITOK, M_NOWAIT, M_ZERO. 2191 * 2192 * Returns 2193 * NULL if there is no memory and M_NOWAIT is set 2194 * An item if successful 2195 */ 2196 2197 static void * 2198 uma_zalloc_internal(uma_zone_t zone, void *udata, int flags) 2199 { 2200 uma_keg_t keg; 2201 uma_slab_t slab; 2202 void *item; 2203 2204 item = NULL; 2205 keg = zone->uz_keg; 2206 2207 #ifdef UMA_DEBUG_ALLOC 2208 printf("INTERNAL: Allocating one item from %s(%p)\n", zone->uz_name, zone); 2209 #endif 2210 ZONE_LOCK(zone); 2211 2212 slab = uma_zone_slab(zone, flags); 2213 if (slab == NULL) { 2214 zone->uz_fails++; 2215 ZONE_UNLOCK(zone); 2216 return (NULL); 2217 } 2218 2219 item = uma_slab_alloc(zone, slab); 2220 2221 zone->uz_allocs++; 2222 2223 ZONE_UNLOCK(zone); 2224 2225 /* 2226 * We have to call both the zone's init (not the keg's init) 2227 * and the zone's ctor. This is because the item is going from 2228 * a keg slab directly to the user, and the user is expecting it 2229 * to be both zone-init'd as well as zone-ctor'd. 2230 */ 2231 if (zone->uz_init != NULL) { 2232 if (zone->uz_init(item, keg->uk_size, flags) != 0) { 2233 uma_zfree_internal(zone, item, udata, SKIP_FINI, 2234 ZFREE_STATFAIL | ZFREE_STATFREE); 2235 return (NULL); 2236 } 2237 } 2238 if (zone->uz_ctor != NULL) { 2239 if (zone->uz_ctor(item, keg->uk_size, udata, flags) != 0) { 2240 uma_zfree_internal(zone, item, udata, SKIP_DTOR, 2241 ZFREE_STATFAIL | ZFREE_STATFREE); 2242 return (NULL); 2243 } 2244 } 2245 if (flags & M_ZERO) 2246 bzero(item, keg->uk_size); 2247 2248 return (item); 2249 } 2250 2251 /* See uma.h */ 2252 void 2253 uma_zfree_arg(uma_zone_t zone, void *item, void *udata) 2254 { 2255 uma_keg_t keg; 2256 uma_cache_t cache; 2257 uma_bucket_t bucket; 2258 int bflags; 2259 int cpu; 2260 2261 keg = zone->uz_keg; 2262 2263 #ifdef UMA_DEBUG_ALLOC_1 2264 printf("Freeing item %p to %s(%p)\n", item, zone->uz_name, zone); 2265 #endif 2266 CTR2(KTR_UMA, "uma_zfree_arg thread %x zone %s", curthread, 2267 zone->uz_name); 2268 2269 if (zone->uz_dtor) 2270 zone->uz_dtor(item, keg->uk_size, udata); 2271 #ifdef INVARIANTS 2272 ZONE_LOCK(zone); 2273 if (keg->uk_flags & UMA_ZONE_MALLOC) 2274 uma_dbg_free(zone, udata, item); 2275 else 2276 uma_dbg_free(zone, NULL, item); 2277 ZONE_UNLOCK(zone); 2278 #endif 2279 /* 2280 * The race here is acceptable. If we miss it we'll just have to wait 2281 * a little longer for the limits to be reset. 2282 */ 2283 if (keg->uk_flags & UMA_ZFLAG_FULL) 2284 goto zfree_internal; 2285 2286 /* 2287 * If possible, free to the per-CPU cache. There are two 2288 * requirements for safe access to the per-CPU cache: (1) the thread 2289 * accessing the cache must not be preempted or yield during access, 2290 * and (2) the thread must not migrate CPUs without switching which 2291 * cache it accesses. We rely on a critical section to prevent 2292 * preemption and migration. We release the critical section in 2293 * order to acquire the zone mutex if we are unable to free to the 2294 * current cache; when we re-acquire the critical section, we must 2295 * detect and handle migration if it has occurred. 2296 */ 2297 zfree_restart: 2298 critical_enter(); 2299 cpu = curcpu; 2300 cache = &zone->uz_cpu[cpu]; 2301 2302 zfree_start: 2303 bucket = cache->uc_freebucket; 2304 2305 if (bucket) { 2306 /* 2307 * Do we have room in our bucket? It is OK for this uz count 2308 * check to be slightly out of sync. 2309 */ 2310 2311 if (bucket->ub_cnt < bucket->ub_entries) { 2312 KASSERT(bucket->ub_bucket[bucket->ub_cnt] == NULL, 2313 ("uma_zfree: Freeing to non free bucket index.")); 2314 bucket->ub_bucket[bucket->ub_cnt] = item; 2315 bucket->ub_cnt++; 2316 cache->uc_frees++; 2317 critical_exit(); 2318 return; 2319 } else if (cache->uc_allocbucket) { 2320 #ifdef UMA_DEBUG_ALLOC 2321 printf("uma_zfree: Swapping buckets.\n"); 2322 #endif 2323 /* 2324 * We have run out of space in our freebucket. 2325 * See if we can switch with our alloc bucket. 2326 */ 2327 if (cache->uc_allocbucket->ub_cnt < 2328 cache->uc_freebucket->ub_cnt) { 2329 bucket = cache->uc_freebucket; 2330 cache->uc_freebucket = cache->uc_allocbucket; 2331 cache->uc_allocbucket = bucket; 2332 goto zfree_start; 2333 } 2334 } 2335 } 2336 /* 2337 * We can get here for two reasons: 2338 * 2339 * 1) The buckets are NULL 2340 * 2) The alloc and free buckets are both somewhat full. 2341 * 2342 * We must go back the zone, which requires acquiring the zone lock, 2343 * which in turn means we must release and re-acquire the critical 2344 * section. Since the critical section is released, we may be 2345 * preempted or migrate. As such, make sure not to maintain any 2346 * thread-local state specific to the cache from prior to releasing 2347 * the critical section. 2348 */ 2349 critical_exit(); 2350 ZONE_LOCK(zone); 2351 critical_enter(); 2352 cpu = curcpu; 2353 cache = &zone->uz_cpu[cpu]; 2354 if (cache->uc_freebucket != NULL) { 2355 if (cache->uc_freebucket->ub_cnt < 2356 cache->uc_freebucket->ub_entries) { 2357 ZONE_UNLOCK(zone); 2358 goto zfree_start; 2359 } 2360 if (cache->uc_allocbucket != NULL && 2361 (cache->uc_allocbucket->ub_cnt < 2362 cache->uc_freebucket->ub_cnt)) { 2363 ZONE_UNLOCK(zone); 2364 goto zfree_start; 2365 } 2366 } 2367 2368 /* Since we have locked the zone we may as well send back our stats */ 2369 zone->uz_allocs += cache->uc_allocs; 2370 cache->uc_allocs = 0; 2371 zone->uz_frees += cache->uc_frees; 2372 cache->uc_frees = 0; 2373 2374 bucket = cache->uc_freebucket; 2375 cache->uc_freebucket = NULL; 2376 2377 /* Can we throw this on the zone full list? */ 2378 if (bucket != NULL) { 2379 #ifdef UMA_DEBUG_ALLOC 2380 printf("uma_zfree: Putting old bucket on the free list.\n"); 2381 #endif 2382 /* ub_cnt is pointing to the last free item */ 2383 KASSERT(bucket->ub_cnt != 0, 2384 ("uma_zfree: Attempting to insert an empty bucket onto the full list.\n")); 2385 LIST_INSERT_HEAD(&zone->uz_full_bucket, 2386 bucket, ub_link); 2387 } 2388 if ((bucket = LIST_FIRST(&zone->uz_free_bucket)) != NULL) { 2389 LIST_REMOVE(bucket, ub_link); 2390 ZONE_UNLOCK(zone); 2391 cache->uc_freebucket = bucket; 2392 goto zfree_start; 2393 } 2394 /* We are no longer associated with this CPU. */ 2395 critical_exit(); 2396 2397 /* And the zone.. */ 2398 ZONE_UNLOCK(zone); 2399 2400 #ifdef UMA_DEBUG_ALLOC 2401 printf("uma_zfree: Allocating new free bucket.\n"); 2402 #endif 2403 bflags = M_NOWAIT; 2404 2405 if (keg->uk_flags & UMA_ZFLAG_CACHEONLY) 2406 bflags |= M_NOVM; 2407 bucket = bucket_alloc(zone->uz_count, bflags); 2408 if (bucket) { 2409 ZONE_LOCK(zone); 2410 LIST_INSERT_HEAD(&zone->uz_free_bucket, 2411 bucket, ub_link); 2412 ZONE_UNLOCK(zone); 2413 goto zfree_restart; 2414 } 2415 2416 /* 2417 * If nothing else caught this, we'll just do an internal free. 2418 */ 2419 zfree_internal: 2420 uma_zfree_internal(zone, item, udata, SKIP_DTOR, ZFREE_STATFAIL | 2421 ZFREE_STATFREE); 2422 2423 return; 2424 } 2425 2426 /* 2427 * Frees an item to an INTERNAL zone or allocates a free bucket 2428 * 2429 * Arguments: 2430 * zone The zone to free to 2431 * item The item we're freeing 2432 * udata User supplied data for the dtor 2433 * skip Skip dtors and finis 2434 */ 2435 static void 2436 uma_zfree_internal(uma_zone_t zone, void *item, void *udata, 2437 enum zfreeskip skip, int flags) 2438 { 2439 uma_slab_t slab; 2440 uma_slabrefcnt_t slabref; 2441 uma_keg_t keg; 2442 u_int8_t *mem; 2443 u_int8_t freei; 2444 2445 keg = zone->uz_keg; 2446 2447 if (skip < SKIP_DTOR && zone->uz_dtor) 2448 zone->uz_dtor(item, keg->uk_size, udata); 2449 if (skip < SKIP_FINI && zone->uz_fini) 2450 zone->uz_fini(item, keg->uk_size); 2451 2452 ZONE_LOCK(zone); 2453 2454 if (flags & ZFREE_STATFAIL) 2455 zone->uz_fails++; 2456 if (flags & ZFREE_STATFREE) 2457 zone->uz_frees++; 2458 2459 if (!(keg->uk_flags & UMA_ZONE_MALLOC)) { 2460 mem = (u_int8_t *)((unsigned long)item & (~UMA_SLAB_MASK)); 2461 if (keg->uk_flags & UMA_ZONE_HASH) 2462 slab = hash_sfind(&keg->uk_hash, mem); 2463 else { 2464 mem += keg->uk_pgoff; 2465 slab = (uma_slab_t)mem; 2466 } 2467 } else { 2468 slab = (uma_slab_t)udata; 2469 } 2470 2471 /* Do we need to remove from any lists? */ 2472 if (slab->us_freecount+1 == keg->uk_ipers) { 2473 LIST_REMOVE(slab, us_link); 2474 LIST_INSERT_HEAD(&keg->uk_free_slab, slab, us_link); 2475 } else if (slab->us_freecount == 0) { 2476 LIST_REMOVE(slab, us_link); 2477 LIST_INSERT_HEAD(&keg->uk_part_slab, slab, us_link); 2478 } 2479 2480 /* Slab management stuff */ 2481 freei = ((unsigned long)item - (unsigned long)slab->us_data) 2482 / keg->uk_rsize; 2483 2484 #ifdef INVARIANTS 2485 if (!skip) 2486 uma_dbg_free(zone, slab, item); 2487 #endif 2488 2489 if (keg->uk_flags & UMA_ZONE_REFCNT) { 2490 slabref = (uma_slabrefcnt_t)slab; 2491 slabref->us_freelist[freei].us_item = slab->us_firstfree; 2492 } else { 2493 slab->us_freelist[freei].us_item = slab->us_firstfree; 2494 } 2495 slab->us_firstfree = freei; 2496 slab->us_freecount++; 2497 2498 /* Zone statistics */ 2499 keg->uk_free++; 2500 2501 if (keg->uk_flags & UMA_ZFLAG_FULL) { 2502 if (keg->uk_pages < keg->uk_maxpages) 2503 keg->uk_flags &= ~UMA_ZFLAG_FULL; 2504 2505 /* We can handle one more allocation */ 2506 wakeup_one(keg); 2507 } 2508 2509 ZONE_UNLOCK(zone); 2510 } 2511 2512 /* See uma.h */ 2513 void 2514 uma_zone_set_max(uma_zone_t zone, int nitems) 2515 { 2516 uma_keg_t keg; 2517 2518 keg = zone->uz_keg; 2519 ZONE_LOCK(zone); 2520 if (keg->uk_ppera > 1) 2521 keg->uk_maxpages = nitems * keg->uk_ppera; 2522 else 2523 keg->uk_maxpages = nitems / keg->uk_ipers; 2524 2525 if (keg->uk_maxpages * keg->uk_ipers < nitems) 2526 keg->uk_maxpages++; 2527 2528 ZONE_UNLOCK(zone); 2529 } 2530 2531 /* See uma.h */ 2532 void 2533 uma_zone_set_init(uma_zone_t zone, uma_init uminit) 2534 { 2535 ZONE_LOCK(zone); 2536 KASSERT(zone->uz_keg->uk_pages == 0, 2537 ("uma_zone_set_init on non-empty keg")); 2538 zone->uz_keg->uk_init = uminit; 2539 ZONE_UNLOCK(zone); 2540 } 2541 2542 /* See uma.h */ 2543 void 2544 uma_zone_set_fini(uma_zone_t zone, uma_fini fini) 2545 { 2546 ZONE_LOCK(zone); 2547 KASSERT(zone->uz_keg->uk_pages == 0, 2548 ("uma_zone_set_fini on non-empty keg")); 2549 zone->uz_keg->uk_fini = fini; 2550 ZONE_UNLOCK(zone); 2551 } 2552 2553 /* See uma.h */ 2554 void 2555 uma_zone_set_zinit(uma_zone_t zone, uma_init zinit) 2556 { 2557 ZONE_LOCK(zone); 2558 KASSERT(zone->uz_keg->uk_pages == 0, 2559 ("uma_zone_set_zinit on non-empty keg")); 2560 zone->uz_init = zinit; 2561 ZONE_UNLOCK(zone); 2562 } 2563 2564 /* See uma.h */ 2565 void 2566 uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini) 2567 { 2568 ZONE_LOCK(zone); 2569 KASSERT(zone->uz_keg->uk_pages == 0, 2570 ("uma_zone_set_zfini on non-empty keg")); 2571 zone->uz_fini = zfini; 2572 ZONE_UNLOCK(zone); 2573 } 2574 2575 /* See uma.h */ 2576 /* XXX uk_freef is not actually used with the zone locked */ 2577 void 2578 uma_zone_set_freef(uma_zone_t zone, uma_free freef) 2579 { 2580 ZONE_LOCK(zone); 2581 zone->uz_keg->uk_freef = freef; 2582 ZONE_UNLOCK(zone); 2583 } 2584 2585 /* See uma.h */ 2586 /* XXX uk_allocf is not actually used with the zone locked */ 2587 void 2588 uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf) 2589 { 2590 ZONE_LOCK(zone); 2591 zone->uz_keg->uk_flags |= UMA_ZFLAG_PRIVALLOC; 2592 zone->uz_keg->uk_allocf = allocf; 2593 ZONE_UNLOCK(zone); 2594 } 2595 2596 /* See uma.h */ 2597 int 2598 uma_zone_set_obj(uma_zone_t zone, struct vm_object *obj, int count) 2599 { 2600 uma_keg_t keg; 2601 vm_offset_t kva; 2602 int pages; 2603 2604 keg = zone->uz_keg; 2605 pages = count / keg->uk_ipers; 2606 2607 if (pages * keg->uk_ipers < count) 2608 pages++; 2609 2610 kva = kmem_alloc_nofault(kernel_map, pages * UMA_SLAB_SIZE); 2611 2612 if (kva == 0) 2613 return (0); 2614 if (obj == NULL) { 2615 obj = vm_object_allocate(OBJT_DEFAULT, 2616 pages); 2617 } else { 2618 VM_OBJECT_LOCK_INIT(obj, "uma object"); 2619 _vm_object_allocate(OBJT_DEFAULT, 2620 pages, obj); 2621 } 2622 ZONE_LOCK(zone); 2623 keg->uk_kva = kva; 2624 keg->uk_obj = obj; 2625 keg->uk_maxpages = pages; 2626 keg->uk_allocf = obj_alloc; 2627 keg->uk_flags |= UMA_ZONE_NOFREE | UMA_ZFLAG_PRIVALLOC; 2628 ZONE_UNLOCK(zone); 2629 return (1); 2630 } 2631 2632 /* See uma.h */ 2633 void 2634 uma_prealloc(uma_zone_t zone, int items) 2635 { 2636 int slabs; 2637 uma_slab_t slab; 2638 uma_keg_t keg; 2639 2640 keg = zone->uz_keg; 2641 ZONE_LOCK(zone); 2642 slabs = items / keg->uk_ipers; 2643 if (slabs * keg->uk_ipers < items) 2644 slabs++; 2645 while (slabs > 0) { 2646 slab = slab_zalloc(zone, M_WAITOK); 2647 LIST_INSERT_HEAD(&keg->uk_free_slab, slab, us_link); 2648 slabs--; 2649 } 2650 ZONE_UNLOCK(zone); 2651 } 2652 2653 /* See uma.h */ 2654 u_int32_t * 2655 uma_find_refcnt(uma_zone_t zone, void *item) 2656 { 2657 uma_slabrefcnt_t slabref; 2658 uma_keg_t keg; 2659 u_int32_t *refcnt; 2660 int idx; 2661 2662 keg = zone->uz_keg; 2663 slabref = (uma_slabrefcnt_t)vtoslab((vm_offset_t)item & 2664 (~UMA_SLAB_MASK)); 2665 KASSERT(slabref != NULL && slabref->us_keg->uk_flags & UMA_ZONE_REFCNT, 2666 ("uma_find_refcnt(): zone possibly not UMA_ZONE_REFCNT")); 2667 idx = ((unsigned long)item - (unsigned long)slabref->us_data) 2668 / keg->uk_rsize; 2669 refcnt = &slabref->us_freelist[idx].us_refcnt; 2670 return refcnt; 2671 } 2672 2673 /* See uma.h */ 2674 void 2675 uma_reclaim(void) 2676 { 2677 #ifdef UMA_DEBUG 2678 printf("UMA: vm asked us to release pages!\n"); 2679 #endif 2680 bucket_enable(); 2681 zone_foreach(zone_drain); 2682 /* 2683 * Some slabs may have been freed but this zone will be visited early 2684 * we visit again so that we can free pages that are empty once other 2685 * zones are drained. We have to do the same for buckets. 2686 */ 2687 zone_drain(slabzone); 2688 zone_drain(slabrefzone); 2689 bucket_zone_drain(); 2690 } 2691 2692 void * 2693 uma_large_malloc(int size, int wait) 2694 { 2695 void *mem; 2696 uma_slab_t slab; 2697 u_int8_t flags; 2698 2699 slab = uma_zalloc_internal(slabzone, NULL, wait); 2700 if (slab == NULL) 2701 return (NULL); 2702 mem = page_alloc(NULL, size, &flags, wait); 2703 if (mem) { 2704 vsetslab((vm_offset_t)mem, slab); 2705 slab->us_data = mem; 2706 slab->us_flags = flags | UMA_SLAB_MALLOC; 2707 slab->us_size = size; 2708 } else { 2709 uma_zfree_internal(slabzone, slab, NULL, SKIP_NONE, 2710 ZFREE_STATFAIL | ZFREE_STATFREE); 2711 } 2712 2713 return (mem); 2714 } 2715 2716 void 2717 uma_large_free(uma_slab_t slab) 2718 { 2719 vsetobj((vm_offset_t)slab->us_data, kmem_object); 2720 page_free(slab->us_data, slab->us_size, slab->us_flags); 2721 uma_zfree_internal(slabzone, slab, NULL, SKIP_NONE, ZFREE_STATFREE); 2722 } 2723 2724 void 2725 uma_print_stats(void) 2726 { 2727 zone_foreach(uma_print_zone); 2728 } 2729 2730 static void 2731 slab_print(uma_slab_t slab) 2732 { 2733 printf("slab: keg %p, data %p, freecount %d, firstfree %d\n", 2734 slab->us_keg, slab->us_data, slab->us_freecount, 2735 slab->us_firstfree); 2736 } 2737 2738 static void 2739 cache_print(uma_cache_t cache) 2740 { 2741 printf("alloc: %p(%d), free: %p(%d)\n", 2742 cache->uc_allocbucket, 2743 cache->uc_allocbucket?cache->uc_allocbucket->ub_cnt:0, 2744 cache->uc_freebucket, 2745 cache->uc_freebucket?cache->uc_freebucket->ub_cnt:0); 2746 } 2747 2748 void 2749 uma_print_zone(uma_zone_t zone) 2750 { 2751 uma_cache_t cache; 2752 uma_keg_t keg; 2753 uma_slab_t slab; 2754 int i; 2755 2756 keg = zone->uz_keg; 2757 printf("%s(%p) size %d(%d) flags %d ipers %d ppera %d out %d free %d\n", 2758 zone->uz_name, zone, keg->uk_size, keg->uk_rsize, keg->uk_flags, 2759 keg->uk_ipers, keg->uk_ppera, 2760 (keg->uk_ipers * keg->uk_pages) - keg->uk_free, keg->uk_free); 2761 printf("Part slabs:\n"); 2762 LIST_FOREACH(slab, &keg->uk_part_slab, us_link) 2763 slab_print(slab); 2764 printf("Free slabs:\n"); 2765 LIST_FOREACH(slab, &keg->uk_free_slab, us_link) 2766 slab_print(slab); 2767 printf("Full slabs:\n"); 2768 LIST_FOREACH(slab, &keg->uk_full_slab, us_link) 2769 slab_print(slab); 2770 for (i = 0; i <= mp_maxid; i++) { 2771 if (CPU_ABSENT(i)) 2772 continue; 2773 cache = &zone->uz_cpu[i]; 2774 printf("CPU %d Cache:\n", i); 2775 cache_print(cache); 2776 } 2777 } 2778 2779 /* 2780 * Generate statistics across both the zone and its per-cpu cache's. Return 2781 * desired statistics if the pointer is non-NULL for that statistic. 2782 * 2783 * Note: does not update the zone statistics, as it can't safely clear the 2784 * per-CPU cache statistic. 2785 * 2786 * XXXRW: Following the uc_allocbucket and uc_freebucket pointers here isn't 2787 * safe from off-CPU; we should modify the caches to track this information 2788 * directly so that we don't have to. 2789 */ 2790 static void 2791 uma_zone_sumstat(uma_zone_t z, int *cachefreep, u_int64_t *allocsp, 2792 u_int64_t *freesp) 2793 { 2794 uma_cache_t cache; 2795 u_int64_t allocs, frees; 2796 int cachefree, cpu; 2797 2798 allocs = frees = 0; 2799 cachefree = 0; 2800 for (cpu = 0; cpu <= mp_maxid; cpu++) { 2801 if (CPU_ABSENT(cpu)) 2802 continue; 2803 cache = &z->uz_cpu[cpu]; 2804 if (cache->uc_allocbucket != NULL) 2805 cachefree += cache->uc_allocbucket->ub_cnt; 2806 if (cache->uc_freebucket != NULL) 2807 cachefree += cache->uc_freebucket->ub_cnt; 2808 allocs += cache->uc_allocs; 2809 frees += cache->uc_frees; 2810 } 2811 allocs += z->uz_allocs; 2812 frees += z->uz_frees; 2813 if (cachefreep != NULL) 2814 *cachefreep = cachefree; 2815 if (allocsp != NULL) 2816 *allocsp = allocs; 2817 if (freesp != NULL) 2818 *freesp = frees; 2819 } 2820 2821 /* 2822 * Sysctl handler for vm.zone 2823 * 2824 * stolen from vm_zone.c 2825 */ 2826 static int 2827 sysctl_vm_zone(SYSCTL_HANDLER_ARGS) 2828 { 2829 int error, len, cnt; 2830 const int linesize = 128; /* conservative */ 2831 int totalfree; 2832 char *tmpbuf, *offset; 2833 uma_zone_t z; 2834 uma_keg_t zk; 2835 char *p; 2836 int cachefree; 2837 uma_bucket_t bucket; 2838 u_int64_t allocs, frees; 2839 2840 cnt = 0; 2841 mtx_lock(&uma_mtx); 2842 LIST_FOREACH(zk, &uma_kegs, uk_link) { 2843 LIST_FOREACH(z, &zk->uk_zones, uz_link) 2844 cnt++; 2845 } 2846 mtx_unlock(&uma_mtx); 2847 MALLOC(tmpbuf, char *, (cnt == 0 ? 1 : cnt) * linesize, 2848 M_TEMP, M_WAITOK); 2849 len = snprintf(tmpbuf, linesize, 2850 "\nITEM SIZE LIMIT USED FREE REQUESTS\n\n"); 2851 if (cnt == 0) 2852 tmpbuf[len - 1] = '\0'; 2853 error = SYSCTL_OUT(req, tmpbuf, cnt == 0 ? len-1 : len); 2854 if (error || cnt == 0) 2855 goto out; 2856 offset = tmpbuf; 2857 mtx_lock(&uma_mtx); 2858 LIST_FOREACH(zk, &uma_kegs, uk_link) { 2859 LIST_FOREACH(z, &zk->uk_zones, uz_link) { 2860 if (cnt == 0) /* list may have changed size */ 2861 break; 2862 ZONE_LOCK(z); 2863 cachefree = 0; 2864 if (!(zk->uk_flags & UMA_ZFLAG_INTERNAL)) { 2865 uma_zone_sumstat(z, &cachefree, &allocs, &frees); 2866 } else { 2867 allocs = z->uz_allocs; 2868 frees = z->uz_frees; 2869 } 2870 2871 LIST_FOREACH(bucket, &z->uz_full_bucket, ub_link) { 2872 cachefree += bucket->ub_cnt; 2873 } 2874 totalfree = zk->uk_free + cachefree; 2875 len = snprintf(offset, linesize, 2876 "%-12.12s %6.6u, %8.8u, %6.6u, %6.6u, %8.8llu\n", 2877 z->uz_name, zk->uk_size, 2878 zk->uk_maxpages * zk->uk_ipers, 2879 (zk->uk_ipers * (zk->uk_pages / zk->uk_ppera)) - totalfree, 2880 totalfree, 2881 (unsigned long long)allocs); 2882 ZONE_UNLOCK(z); 2883 for (p = offset + 12; p > offset && *p == ' '; --p) 2884 /* nothing */ ; 2885 p[1] = ':'; 2886 cnt--; 2887 offset += len; 2888 } 2889 } 2890 mtx_unlock(&uma_mtx); 2891 *offset++ = '\0'; 2892 error = SYSCTL_OUT(req, tmpbuf, offset - tmpbuf); 2893 out: 2894 FREE(tmpbuf, M_TEMP); 2895 return (error); 2896 } 2897 2898 static int 2899 sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS) 2900 { 2901 uma_keg_t kz; 2902 uma_zone_t z; 2903 int count; 2904 2905 count = 0; 2906 mtx_lock(&uma_mtx); 2907 LIST_FOREACH(kz, &uma_kegs, uk_link) { 2908 LIST_FOREACH(z, &kz->uk_zones, uz_link) 2909 count++; 2910 } 2911 mtx_unlock(&uma_mtx); 2912 return (sysctl_handle_int(oidp, &count, 0, req)); 2913 } 2914 2915 static int 2916 sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS) 2917 { 2918 struct uma_stream_header ush; 2919 struct uma_type_header uth; 2920 struct uma_percpu_stat ups; 2921 uma_bucket_t bucket; 2922 struct sbuf sbuf; 2923 uma_cache_t cache; 2924 uma_keg_t kz; 2925 uma_zone_t z; 2926 char *buffer; 2927 int buflen, count, error, i; 2928 2929 mtx_lock(&uma_mtx); 2930 restart: 2931 mtx_assert(&uma_mtx, MA_OWNED); 2932 count = 0; 2933 LIST_FOREACH(kz, &uma_kegs, uk_link) { 2934 LIST_FOREACH(z, &kz->uk_zones, uz_link) 2935 count++; 2936 } 2937 mtx_unlock(&uma_mtx); 2938 2939 buflen = sizeof(ush) + count * (sizeof(uth) + sizeof(ups) * 2940 (mp_maxid + 1)) + 1; 2941 buffer = malloc(buflen, M_TEMP, M_WAITOK | M_ZERO); 2942 2943 mtx_lock(&uma_mtx); 2944 i = 0; 2945 LIST_FOREACH(kz, &uma_kegs, uk_link) { 2946 LIST_FOREACH(z, &kz->uk_zones, uz_link) 2947 i++; 2948 } 2949 if (i > count) { 2950 free(buffer, M_TEMP); 2951 goto restart; 2952 } 2953 count = i; 2954 2955 sbuf_new(&sbuf, buffer, buflen, SBUF_FIXEDLEN); 2956 2957 /* 2958 * Insert stream header. 2959 */ 2960 bzero(&ush, sizeof(ush)); 2961 ush.ush_version = UMA_STREAM_VERSION; 2962 ush.ush_maxcpus = (mp_maxid + 1); 2963 ush.ush_count = count; 2964 if (sbuf_bcat(&sbuf, &ush, sizeof(ush)) < 0) { 2965 mtx_unlock(&uma_mtx); 2966 error = ENOMEM; 2967 goto out; 2968 } 2969 2970 LIST_FOREACH(kz, &uma_kegs, uk_link) { 2971 LIST_FOREACH(z, &kz->uk_zones, uz_link) { 2972 bzero(&uth, sizeof(uth)); 2973 ZONE_LOCK(z); 2974 strlcpy(uth.uth_name, z->uz_name, UTH_MAX_NAME); 2975 uth.uth_align = kz->uk_align; 2976 uth.uth_pages = kz->uk_pages; 2977 uth.uth_keg_free = kz->uk_free; 2978 uth.uth_size = kz->uk_size; 2979 uth.uth_rsize = kz->uk_rsize; 2980 uth.uth_maxpages = kz->uk_maxpages; 2981 if (kz->uk_ppera > 1) 2982 uth.uth_limit = kz->uk_maxpages / 2983 kz->uk_ppera; 2984 else 2985 uth.uth_limit = kz->uk_maxpages * 2986 kz->uk_ipers; 2987 2988 /* 2989 * A zone is secondary is it is not the first entry 2990 * on the keg's zone list. 2991 */ 2992 if ((kz->uk_flags & UMA_ZONE_SECONDARY) && 2993 (LIST_FIRST(&kz->uk_zones) != z)) 2994 uth.uth_zone_flags = UTH_ZONE_SECONDARY; 2995 2996 LIST_FOREACH(bucket, &z->uz_full_bucket, ub_link) 2997 uth.uth_zone_free += bucket->ub_cnt; 2998 uth.uth_allocs = z->uz_allocs; 2999 uth.uth_frees = z->uz_frees; 3000 uth.uth_fails = z->uz_fails; 3001 if (sbuf_bcat(&sbuf, &uth, sizeof(uth)) < 0) { 3002 ZONE_UNLOCK(z); 3003 mtx_unlock(&uma_mtx); 3004 error = ENOMEM; 3005 goto out; 3006 } 3007 /* 3008 * While it is not normally safe to access the cache 3009 * bucket pointers while not on the CPU that owns the 3010 * cache, we only allow the pointers to be exchanged 3011 * without the zone lock held, not invalidated, so 3012 * accept the possible race associated with bucket 3013 * exchange during monitoring. 3014 */ 3015 for (i = 0; i < (mp_maxid + 1); i++) { 3016 bzero(&ups, sizeof(ups)); 3017 if (kz->uk_flags & UMA_ZFLAG_INTERNAL) 3018 goto skip; 3019 cache = &z->uz_cpu[i]; 3020 if (cache->uc_allocbucket != NULL) 3021 ups.ups_cache_free += 3022 cache->uc_allocbucket->ub_cnt; 3023 if (cache->uc_freebucket != NULL) 3024 ups.ups_cache_free += 3025 cache->uc_freebucket->ub_cnt; 3026 ups.ups_allocs = cache->uc_allocs; 3027 ups.ups_frees = cache->uc_frees; 3028 skip: 3029 if (sbuf_bcat(&sbuf, &ups, sizeof(ups)) < 0) { 3030 ZONE_UNLOCK(z); 3031 mtx_unlock(&uma_mtx); 3032 error = ENOMEM; 3033 goto out; 3034 } 3035 } 3036 ZONE_UNLOCK(z); 3037 } 3038 } 3039 mtx_unlock(&uma_mtx); 3040 sbuf_finish(&sbuf); 3041 error = SYSCTL_OUT(req, sbuf_data(&sbuf), sbuf_len(&sbuf)); 3042 out: 3043 free(buffer, M_TEMP); 3044 return (error); 3045 } 3046 3047 #ifdef DDB 3048 DB_SHOW_COMMAND(uma, db_show_uma) 3049 { 3050 u_int64_t allocs, frees; 3051 uma_bucket_t bucket; 3052 uma_keg_t kz; 3053 uma_zone_t z; 3054 int cachefree; 3055 3056 db_printf("%18s %12s %12s %12s %8s\n", "Zone", "Allocs", "Frees", 3057 "Used", "Cache"); 3058 LIST_FOREACH(kz, &uma_kegs, uk_link) { 3059 LIST_FOREACH(z, &kz->uk_zones, uz_link) { 3060 if (kz->uk_flags & UMA_ZFLAG_INTERNAL) { 3061 allocs = z->uz_allocs; 3062 frees = z->uz_frees; 3063 cachefree = 0; 3064 } else 3065 uma_zone_sumstat(z, &cachefree, &allocs, 3066 &frees); 3067 if (!((kz->uk_flags & UMA_ZONE_SECONDARY) && 3068 (LIST_FIRST(&kz->uk_zones) != z))) 3069 cachefree += kz->uk_free; 3070 LIST_FOREACH(bucket, &z->uz_full_bucket, ub_link) 3071 cachefree += bucket->ub_cnt; 3072 db_printf("%18s %12ju %12ju %12ju %8d\n", z->uz_name, 3073 allocs, frees, allocs - frees, cachefree); 3074 } 3075 } 3076 } 3077 #endif 3078