1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2002-2005, 2009, 2013 Jeffrey Roberson <jeff@FreeBSD.org> 5 * Copyright (c) 2004, 2005 Bosko Milekic <bmilekic@FreeBSD.org> 6 * Copyright (c) 2004-2006 Robert N. M. Watson 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice unmodified, this list of conditions, and the following 14 * disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 /* 32 * uma_core.c Implementation of the Universal Memory allocator 33 * 34 * This allocator is intended to replace the multitude of similar object caches 35 * in the standard FreeBSD kernel. The intent is to be flexible as well as 36 * efficient. A primary design goal is to return unused memory to the rest of 37 * the system. This will make the system as a whole more flexible due to the 38 * ability to move memory to subsystems which most need it instead of leaving 39 * pools of reserved memory unused. 40 * 41 * The basic ideas stem from similar slab/zone based allocators whose algorithms 42 * are well known. 43 * 44 */ 45 46 /* 47 * TODO: 48 * - Improve memory usage for large allocations 49 * - Investigate cache size adjustments 50 */ 51 52 #include <sys/cdefs.h> 53 __FBSDID("$FreeBSD$"); 54 55 #include "opt_ddb.h" 56 #include "opt_param.h" 57 #include "opt_vm.h" 58 59 #include <sys/param.h> 60 #include <sys/systm.h> 61 #include <sys/bitset.h> 62 #include <sys/eventhandler.h> 63 #include <sys/kernel.h> 64 #include <sys/types.h> 65 #include <sys/queue.h> 66 #include <sys/malloc.h> 67 #include <sys/ktr.h> 68 #include <sys/lock.h> 69 #include <sys/sysctl.h> 70 #include <sys/mutex.h> 71 #include <sys/proc.h> 72 #include <sys/random.h> 73 #include <sys/rwlock.h> 74 #include <sys/sbuf.h> 75 #include <sys/sched.h> 76 #include <sys/smp.h> 77 #include <sys/taskqueue.h> 78 #include <sys/vmmeter.h> 79 80 #include <vm/vm.h> 81 #include <vm/vm_object.h> 82 #include <vm/vm_page.h> 83 #include <vm/vm_pageout.h> 84 #include <vm/vm_param.h> 85 #include <vm/vm_map.h> 86 #include <vm/vm_kern.h> 87 #include <vm/vm_extern.h> 88 #include <vm/uma.h> 89 #include <vm/uma_int.h> 90 #include <vm/uma_dbg.h> 91 92 #include <ddb/ddb.h> 93 94 #ifdef DEBUG_MEMGUARD 95 #include <vm/memguard.h> 96 #endif 97 98 /* 99 * This is the zone and keg from which all zones are spawned. The idea is that 100 * even the zone & keg heads are allocated from the allocator, so we use the 101 * bss section to bootstrap us. 102 */ 103 static struct uma_keg masterkeg; 104 static struct uma_zone masterzone_k; 105 static struct uma_zone masterzone_z; 106 static uma_zone_t kegs = &masterzone_k; 107 static uma_zone_t zones = &masterzone_z; 108 109 /* This is the zone from which all of uma_slab_t's are allocated. */ 110 static uma_zone_t slabzone; 111 112 /* 113 * The initial hash tables come out of this zone so they can be allocated 114 * prior to malloc coming up. 115 */ 116 static uma_zone_t hashzone; 117 118 /* The boot-time adjusted value for cache line alignment. */ 119 int uma_align_cache = 64 - 1; 120 121 static MALLOC_DEFINE(M_UMAHASH, "UMAHash", "UMA Hash Buckets"); 122 123 /* 124 * Are we allowed to allocate buckets? 125 */ 126 static int bucketdisable = 1; 127 128 /* Linked list of all kegs in the system */ 129 static LIST_HEAD(,uma_keg) uma_kegs = LIST_HEAD_INITIALIZER(uma_kegs); 130 131 /* Linked list of all cache-only zones in the system */ 132 static LIST_HEAD(,uma_zone) uma_cachezones = 133 LIST_HEAD_INITIALIZER(uma_cachezones); 134 135 /* This RW lock protects the keg list */ 136 static struct rwlock_padalign __exclusive_cache_line uma_rwlock; 137 138 /* 139 * Pointer and counter to pool of pages, that is preallocated at 140 * startup to bootstrap UMA. Early zones continue to use the pool 141 * until it is depleted, so allocations may happen after boot, thus 142 * we need a mutex to protect it. 143 */ 144 static char *bootmem; 145 static int boot_pages; 146 static struct mtx uma_boot_pages_mtx; 147 148 static struct sx uma_drain_lock; 149 150 /* kmem soft limit. */ 151 static unsigned long uma_kmem_limit; 152 static volatile unsigned long uma_kmem_total; 153 154 /* Is the VM done starting up? */ 155 static int booted = 0; 156 #define UMA_STARTUP 1 157 #define UMA_STARTUP2 2 158 159 /* 160 * This is the handle used to schedule events that need to happen 161 * outside of the allocation fast path. 162 */ 163 static struct callout uma_callout; 164 #define UMA_TIMEOUT 20 /* Seconds for callout interval. */ 165 166 /* 167 * This structure is passed as the zone ctor arg so that I don't have to create 168 * a special allocation function just for zones. 169 */ 170 struct uma_zctor_args { 171 const char *name; 172 size_t size; 173 uma_ctor ctor; 174 uma_dtor dtor; 175 uma_init uminit; 176 uma_fini fini; 177 uma_import import; 178 uma_release release; 179 void *arg; 180 uma_keg_t keg; 181 int align; 182 uint32_t flags; 183 }; 184 185 struct uma_kctor_args { 186 uma_zone_t zone; 187 size_t size; 188 uma_init uminit; 189 uma_fini fini; 190 int align; 191 uint32_t flags; 192 }; 193 194 struct uma_bucket_zone { 195 uma_zone_t ubz_zone; 196 char *ubz_name; 197 int ubz_entries; /* Number of items it can hold. */ 198 int ubz_maxsize; /* Maximum allocation size per-item. */ 199 }; 200 201 /* 202 * Compute the actual number of bucket entries to pack them in power 203 * of two sizes for more efficient space utilization. 204 */ 205 #define BUCKET_SIZE(n) \ 206 (((sizeof(void *) * (n)) - sizeof(struct uma_bucket)) / sizeof(void *)) 207 208 #define BUCKET_MAX BUCKET_SIZE(256) 209 210 struct uma_bucket_zone bucket_zones[] = { 211 { NULL, "4 Bucket", BUCKET_SIZE(4), 4096 }, 212 { NULL, "6 Bucket", BUCKET_SIZE(6), 3072 }, 213 { NULL, "8 Bucket", BUCKET_SIZE(8), 2048 }, 214 { NULL, "12 Bucket", BUCKET_SIZE(12), 1536 }, 215 { NULL, "16 Bucket", BUCKET_SIZE(16), 1024 }, 216 { NULL, "32 Bucket", BUCKET_SIZE(32), 512 }, 217 { NULL, "64 Bucket", BUCKET_SIZE(64), 256 }, 218 { NULL, "128 Bucket", BUCKET_SIZE(128), 128 }, 219 { NULL, "256 Bucket", BUCKET_SIZE(256), 64 }, 220 { NULL, NULL, 0} 221 }; 222 223 /* 224 * Flags and enumerations to be passed to internal functions. 225 */ 226 enum zfreeskip { SKIP_NONE = 0, SKIP_DTOR, SKIP_FINI }; 227 228 /* Prototypes.. */ 229 230 static void *noobj_alloc(uma_zone_t, vm_size_t, uint8_t *, int); 231 static void *page_alloc(uma_zone_t, vm_size_t, uint8_t *, int); 232 static void *startup_alloc(uma_zone_t, vm_size_t, uint8_t *, int); 233 static void page_free(void *, vm_size_t, uint8_t); 234 static uma_slab_t keg_alloc_slab(uma_keg_t, uma_zone_t, int); 235 static void cache_drain(uma_zone_t); 236 static void bucket_drain(uma_zone_t, uma_bucket_t); 237 static void bucket_cache_drain(uma_zone_t zone); 238 static int keg_ctor(void *, int, void *, int); 239 static void keg_dtor(void *, int, void *); 240 static int zone_ctor(void *, int, void *, int); 241 static void zone_dtor(void *, int, void *); 242 static int zero_init(void *, int, int); 243 static void keg_small_init(uma_keg_t keg); 244 static void keg_large_init(uma_keg_t keg); 245 static void zone_foreach(void (*zfunc)(uma_zone_t)); 246 static void zone_timeout(uma_zone_t zone); 247 static int hash_alloc(struct uma_hash *); 248 static int hash_expand(struct uma_hash *, struct uma_hash *); 249 static void hash_free(struct uma_hash *hash); 250 static void uma_timeout(void *); 251 static void uma_startup3(void); 252 static void *zone_alloc_item(uma_zone_t, void *, int); 253 static void zone_free_item(uma_zone_t, void *, void *, enum zfreeskip); 254 static void bucket_enable(void); 255 static void bucket_init(void); 256 static uma_bucket_t bucket_alloc(uma_zone_t zone, void *, int); 257 static void bucket_free(uma_zone_t zone, uma_bucket_t, void *); 258 static void bucket_zone_drain(void); 259 static uma_bucket_t zone_alloc_bucket(uma_zone_t zone, void *, int flags); 260 static uma_slab_t zone_fetch_slab(uma_zone_t zone, uma_keg_t last, int flags); 261 static uma_slab_t zone_fetch_slab_multi(uma_zone_t zone, uma_keg_t last, int flags); 262 static void *slab_alloc_item(uma_keg_t keg, uma_slab_t slab); 263 static void slab_free_item(uma_keg_t keg, uma_slab_t slab, void *item); 264 static uma_keg_t uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit, 265 uma_fini fini, int align, uint32_t flags); 266 static int zone_import(uma_zone_t zone, void **bucket, int max, int flags); 267 static void zone_release(uma_zone_t zone, void **bucket, int cnt); 268 static void uma_zero_item(void *item, uma_zone_t zone); 269 270 void uma_print_zone(uma_zone_t); 271 void uma_print_stats(void); 272 static int sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS); 273 static int sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS); 274 275 #ifdef INVARIANTS 276 static void uma_dbg_free(uma_zone_t zone, uma_slab_t slab, void *item); 277 static void uma_dbg_alloc(uma_zone_t zone, uma_slab_t slab, void *item); 278 #endif 279 280 SYSINIT(uma_startup3, SI_SUB_VM_CONF, SI_ORDER_SECOND, uma_startup3, NULL); 281 282 SYSCTL_PROC(_vm, OID_AUTO, zone_count, CTLFLAG_RD|CTLTYPE_INT, 283 0, 0, sysctl_vm_zone_count, "I", "Number of UMA zones"); 284 285 SYSCTL_PROC(_vm, OID_AUTO, zone_stats, CTLFLAG_RD|CTLTYPE_STRUCT, 286 0, 0, sysctl_vm_zone_stats, "s,struct uma_type_header", "Zone Stats"); 287 288 static int zone_warnings = 1; 289 SYSCTL_INT(_vm, OID_AUTO, zone_warnings, CTLFLAG_RWTUN, &zone_warnings, 0, 290 "Warn when UMA zones becomes full"); 291 292 /* Adjust bytes under management by UMA. */ 293 static inline void 294 uma_total_dec(unsigned long size) 295 { 296 297 atomic_subtract_long(&uma_kmem_total, size); 298 } 299 300 static inline void 301 uma_total_inc(unsigned long size) 302 { 303 304 if (atomic_fetchadd_long(&uma_kmem_total, size) > uma_kmem_limit) 305 uma_reclaim_wakeup(); 306 } 307 308 /* 309 * This routine checks to see whether or not it's safe to enable buckets. 310 */ 311 static void 312 bucket_enable(void) 313 { 314 bucketdisable = vm_page_count_min(); 315 } 316 317 /* 318 * Initialize bucket_zones, the array of zones of buckets of various sizes. 319 * 320 * For each zone, calculate the memory required for each bucket, consisting 321 * of the header and an array of pointers. 322 */ 323 static void 324 bucket_init(void) 325 { 326 struct uma_bucket_zone *ubz; 327 int size; 328 329 for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++) { 330 size = roundup(sizeof(struct uma_bucket), sizeof(void *)); 331 size += sizeof(void *) * ubz->ubz_entries; 332 ubz->ubz_zone = uma_zcreate(ubz->ubz_name, size, 333 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 334 UMA_ZONE_MTXCLASS | UMA_ZFLAG_BUCKET); 335 } 336 } 337 338 /* 339 * Given a desired number of entries for a bucket, return the zone from which 340 * to allocate the bucket. 341 */ 342 static struct uma_bucket_zone * 343 bucket_zone_lookup(int entries) 344 { 345 struct uma_bucket_zone *ubz; 346 347 for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++) 348 if (ubz->ubz_entries >= entries) 349 return (ubz); 350 ubz--; 351 return (ubz); 352 } 353 354 static int 355 bucket_select(int size) 356 { 357 struct uma_bucket_zone *ubz; 358 359 ubz = &bucket_zones[0]; 360 if (size > ubz->ubz_maxsize) 361 return MAX((ubz->ubz_maxsize * ubz->ubz_entries) / size, 1); 362 363 for (; ubz->ubz_entries != 0; ubz++) 364 if (ubz->ubz_maxsize < size) 365 break; 366 ubz--; 367 return (ubz->ubz_entries); 368 } 369 370 static uma_bucket_t 371 bucket_alloc(uma_zone_t zone, void *udata, int flags) 372 { 373 struct uma_bucket_zone *ubz; 374 uma_bucket_t bucket; 375 376 /* 377 * This is to stop us from allocating per cpu buckets while we're 378 * running out of vm.boot_pages. Otherwise, we would exhaust the 379 * boot pages. This also prevents us from allocating buckets in 380 * low memory situations. 381 */ 382 if (bucketdisable) 383 return (NULL); 384 /* 385 * To limit bucket recursion we store the original zone flags 386 * in a cookie passed via zalloc_arg/zfree_arg. This allows the 387 * NOVM flag to persist even through deep recursions. We also 388 * store ZFLAG_BUCKET once we have recursed attempting to allocate 389 * a bucket for a bucket zone so we do not allow infinite bucket 390 * recursion. This cookie will even persist to frees of unused 391 * buckets via the allocation path or bucket allocations in the 392 * free path. 393 */ 394 if ((zone->uz_flags & UMA_ZFLAG_BUCKET) == 0) 395 udata = (void *)(uintptr_t)zone->uz_flags; 396 else { 397 if ((uintptr_t)udata & UMA_ZFLAG_BUCKET) 398 return (NULL); 399 udata = (void *)((uintptr_t)udata | UMA_ZFLAG_BUCKET); 400 } 401 if ((uintptr_t)udata & UMA_ZFLAG_CACHEONLY) 402 flags |= M_NOVM; 403 ubz = bucket_zone_lookup(zone->uz_count); 404 if (ubz->ubz_zone == zone && (ubz + 1)->ubz_entries != 0) 405 ubz++; 406 bucket = uma_zalloc_arg(ubz->ubz_zone, udata, flags); 407 if (bucket) { 408 #ifdef INVARIANTS 409 bzero(bucket->ub_bucket, sizeof(void *) * ubz->ubz_entries); 410 #endif 411 bucket->ub_cnt = 0; 412 bucket->ub_entries = ubz->ubz_entries; 413 } 414 415 return (bucket); 416 } 417 418 static void 419 bucket_free(uma_zone_t zone, uma_bucket_t bucket, void *udata) 420 { 421 struct uma_bucket_zone *ubz; 422 423 KASSERT(bucket->ub_cnt == 0, 424 ("bucket_free: Freeing a non free bucket.")); 425 if ((zone->uz_flags & UMA_ZFLAG_BUCKET) == 0) 426 udata = (void *)(uintptr_t)zone->uz_flags; 427 ubz = bucket_zone_lookup(bucket->ub_entries); 428 uma_zfree_arg(ubz->ubz_zone, bucket, udata); 429 } 430 431 static void 432 bucket_zone_drain(void) 433 { 434 struct uma_bucket_zone *ubz; 435 436 for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++) 437 zone_drain(ubz->ubz_zone); 438 } 439 440 static void 441 zone_log_warning(uma_zone_t zone) 442 { 443 static const struct timeval warninterval = { 300, 0 }; 444 445 if (!zone_warnings || zone->uz_warning == NULL) 446 return; 447 448 if (ratecheck(&zone->uz_ratecheck, &warninterval)) 449 printf("[zone: %s] %s\n", zone->uz_name, zone->uz_warning); 450 } 451 452 static inline void 453 zone_maxaction(uma_zone_t zone) 454 { 455 456 if (zone->uz_maxaction.ta_func != NULL) 457 taskqueue_enqueue(taskqueue_thread, &zone->uz_maxaction); 458 } 459 460 static void 461 zone_foreach_keg(uma_zone_t zone, void (*kegfn)(uma_keg_t)) 462 { 463 uma_klink_t klink; 464 465 LIST_FOREACH(klink, &zone->uz_kegs, kl_link) 466 kegfn(klink->kl_keg); 467 } 468 469 /* 470 * Routine called by timeout which is used to fire off some time interval 471 * based calculations. (stats, hash size, etc.) 472 * 473 * Arguments: 474 * arg Unused 475 * 476 * Returns: 477 * Nothing 478 */ 479 static void 480 uma_timeout(void *unused) 481 { 482 bucket_enable(); 483 zone_foreach(zone_timeout); 484 485 /* Reschedule this event */ 486 callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL); 487 } 488 489 /* 490 * Routine to perform timeout driven calculations. This expands the 491 * hashes and does per cpu statistics aggregation. 492 * 493 * Returns nothing. 494 */ 495 static void 496 keg_timeout(uma_keg_t keg) 497 { 498 499 KEG_LOCK(keg); 500 /* 501 * Expand the keg hash table. 502 * 503 * This is done if the number of slabs is larger than the hash size. 504 * What I'm trying to do here is completely reduce collisions. This 505 * may be a little aggressive. Should I allow for two collisions max? 506 */ 507 if (keg->uk_flags & UMA_ZONE_HASH && 508 keg->uk_pages / keg->uk_ppera >= keg->uk_hash.uh_hashsize) { 509 struct uma_hash newhash; 510 struct uma_hash oldhash; 511 int ret; 512 513 /* 514 * This is so involved because allocating and freeing 515 * while the keg lock is held will lead to deadlock. 516 * I have to do everything in stages and check for 517 * races. 518 */ 519 newhash = keg->uk_hash; 520 KEG_UNLOCK(keg); 521 ret = hash_alloc(&newhash); 522 KEG_LOCK(keg); 523 if (ret) { 524 if (hash_expand(&keg->uk_hash, &newhash)) { 525 oldhash = keg->uk_hash; 526 keg->uk_hash = newhash; 527 } else 528 oldhash = newhash; 529 530 KEG_UNLOCK(keg); 531 hash_free(&oldhash); 532 return; 533 } 534 } 535 KEG_UNLOCK(keg); 536 } 537 538 static void 539 zone_timeout(uma_zone_t zone) 540 { 541 542 zone_foreach_keg(zone, &keg_timeout); 543 } 544 545 /* 546 * Allocate and zero fill the next sized hash table from the appropriate 547 * backing store. 548 * 549 * Arguments: 550 * hash A new hash structure with the old hash size in uh_hashsize 551 * 552 * Returns: 553 * 1 on success and 0 on failure. 554 */ 555 static int 556 hash_alloc(struct uma_hash *hash) 557 { 558 int oldsize; 559 int alloc; 560 561 oldsize = hash->uh_hashsize; 562 563 /* We're just going to go to a power of two greater */ 564 if (oldsize) { 565 hash->uh_hashsize = oldsize * 2; 566 alloc = sizeof(hash->uh_slab_hash[0]) * hash->uh_hashsize; 567 hash->uh_slab_hash = (struct slabhead *)malloc(alloc, 568 M_UMAHASH, M_NOWAIT); 569 } else { 570 alloc = sizeof(hash->uh_slab_hash[0]) * UMA_HASH_SIZE_INIT; 571 hash->uh_slab_hash = zone_alloc_item(hashzone, NULL, 572 M_WAITOK); 573 hash->uh_hashsize = UMA_HASH_SIZE_INIT; 574 } 575 if (hash->uh_slab_hash) { 576 bzero(hash->uh_slab_hash, alloc); 577 hash->uh_hashmask = hash->uh_hashsize - 1; 578 return (1); 579 } 580 581 return (0); 582 } 583 584 /* 585 * Expands the hash table for HASH zones. This is done from zone_timeout 586 * to reduce collisions. This must not be done in the regular allocation 587 * path, otherwise, we can recurse on the vm while allocating pages. 588 * 589 * Arguments: 590 * oldhash The hash you want to expand 591 * newhash The hash structure for the new table 592 * 593 * Returns: 594 * Nothing 595 * 596 * Discussion: 597 */ 598 static int 599 hash_expand(struct uma_hash *oldhash, struct uma_hash *newhash) 600 { 601 uma_slab_t slab; 602 int hval; 603 int i; 604 605 if (!newhash->uh_slab_hash) 606 return (0); 607 608 if (oldhash->uh_hashsize >= newhash->uh_hashsize) 609 return (0); 610 611 /* 612 * I need to investigate hash algorithms for resizing without a 613 * full rehash. 614 */ 615 616 for (i = 0; i < oldhash->uh_hashsize; i++) 617 while (!SLIST_EMPTY(&oldhash->uh_slab_hash[i])) { 618 slab = SLIST_FIRST(&oldhash->uh_slab_hash[i]); 619 SLIST_REMOVE_HEAD(&oldhash->uh_slab_hash[i], us_hlink); 620 hval = UMA_HASH(newhash, slab->us_data); 621 SLIST_INSERT_HEAD(&newhash->uh_slab_hash[hval], 622 slab, us_hlink); 623 } 624 625 return (1); 626 } 627 628 /* 629 * Free the hash bucket to the appropriate backing store. 630 * 631 * Arguments: 632 * slab_hash The hash bucket we're freeing 633 * hashsize The number of entries in that hash bucket 634 * 635 * Returns: 636 * Nothing 637 */ 638 static void 639 hash_free(struct uma_hash *hash) 640 { 641 if (hash->uh_slab_hash == NULL) 642 return; 643 if (hash->uh_hashsize == UMA_HASH_SIZE_INIT) 644 zone_free_item(hashzone, hash->uh_slab_hash, NULL, SKIP_NONE); 645 else 646 free(hash->uh_slab_hash, M_UMAHASH); 647 } 648 649 /* 650 * Frees all outstanding items in a bucket 651 * 652 * Arguments: 653 * zone The zone to free to, must be unlocked. 654 * bucket The free/alloc bucket with items, cpu queue must be locked. 655 * 656 * Returns: 657 * Nothing 658 */ 659 660 static void 661 bucket_drain(uma_zone_t zone, uma_bucket_t bucket) 662 { 663 int i; 664 665 if (bucket == NULL) 666 return; 667 668 if (zone->uz_fini) 669 for (i = 0; i < bucket->ub_cnt; i++) 670 zone->uz_fini(bucket->ub_bucket[i], zone->uz_size); 671 zone->uz_release(zone->uz_arg, bucket->ub_bucket, bucket->ub_cnt); 672 bucket->ub_cnt = 0; 673 } 674 675 /* 676 * Drains the per cpu caches for a zone. 677 * 678 * NOTE: This may only be called while the zone is being turn down, and not 679 * during normal operation. This is necessary in order that we do not have 680 * to migrate CPUs to drain the per-CPU caches. 681 * 682 * Arguments: 683 * zone The zone to drain, must be unlocked. 684 * 685 * Returns: 686 * Nothing 687 */ 688 static void 689 cache_drain(uma_zone_t zone) 690 { 691 uma_cache_t cache; 692 int cpu; 693 694 /* 695 * XXX: It is safe to not lock the per-CPU caches, because we're 696 * tearing down the zone anyway. I.e., there will be no further use 697 * of the caches at this point. 698 * 699 * XXX: It would good to be able to assert that the zone is being 700 * torn down to prevent improper use of cache_drain(). 701 * 702 * XXX: We lock the zone before passing into bucket_cache_drain() as 703 * it is used elsewhere. Should the tear-down path be made special 704 * there in some form? 705 */ 706 CPU_FOREACH(cpu) { 707 cache = &zone->uz_cpu[cpu]; 708 bucket_drain(zone, cache->uc_allocbucket); 709 bucket_drain(zone, cache->uc_freebucket); 710 if (cache->uc_allocbucket != NULL) 711 bucket_free(zone, cache->uc_allocbucket, NULL); 712 if (cache->uc_freebucket != NULL) 713 bucket_free(zone, cache->uc_freebucket, NULL); 714 cache->uc_allocbucket = cache->uc_freebucket = NULL; 715 } 716 ZONE_LOCK(zone); 717 bucket_cache_drain(zone); 718 ZONE_UNLOCK(zone); 719 } 720 721 static void 722 cache_shrink(uma_zone_t zone) 723 { 724 725 if (zone->uz_flags & UMA_ZFLAG_INTERNAL) 726 return; 727 728 ZONE_LOCK(zone); 729 zone->uz_count = (zone->uz_count_min + zone->uz_count) / 2; 730 ZONE_UNLOCK(zone); 731 } 732 733 static void 734 cache_drain_safe_cpu(uma_zone_t zone) 735 { 736 uma_cache_t cache; 737 uma_bucket_t b1, b2; 738 739 if (zone->uz_flags & UMA_ZFLAG_INTERNAL) 740 return; 741 742 b1 = b2 = NULL; 743 ZONE_LOCK(zone); 744 critical_enter(); 745 cache = &zone->uz_cpu[curcpu]; 746 if (cache->uc_allocbucket) { 747 if (cache->uc_allocbucket->ub_cnt != 0) 748 LIST_INSERT_HEAD(&zone->uz_buckets, 749 cache->uc_allocbucket, ub_link); 750 else 751 b1 = cache->uc_allocbucket; 752 cache->uc_allocbucket = NULL; 753 } 754 if (cache->uc_freebucket) { 755 if (cache->uc_freebucket->ub_cnt != 0) 756 LIST_INSERT_HEAD(&zone->uz_buckets, 757 cache->uc_freebucket, ub_link); 758 else 759 b2 = cache->uc_freebucket; 760 cache->uc_freebucket = NULL; 761 } 762 critical_exit(); 763 ZONE_UNLOCK(zone); 764 if (b1) 765 bucket_free(zone, b1, NULL); 766 if (b2) 767 bucket_free(zone, b2, NULL); 768 } 769 770 /* 771 * Safely drain per-CPU caches of a zone(s) to alloc bucket. 772 * This is an expensive call because it needs to bind to all CPUs 773 * one by one and enter a critical section on each of them in order 774 * to safely access their cache buckets. 775 * Zone lock must not be held on call this function. 776 */ 777 static void 778 cache_drain_safe(uma_zone_t zone) 779 { 780 int cpu; 781 782 /* 783 * Polite bucket sizes shrinking was not enouth, shrink aggressively. 784 */ 785 if (zone) 786 cache_shrink(zone); 787 else 788 zone_foreach(cache_shrink); 789 790 CPU_FOREACH(cpu) { 791 thread_lock(curthread); 792 sched_bind(curthread, cpu); 793 thread_unlock(curthread); 794 795 if (zone) 796 cache_drain_safe_cpu(zone); 797 else 798 zone_foreach(cache_drain_safe_cpu); 799 } 800 thread_lock(curthread); 801 sched_unbind(curthread); 802 thread_unlock(curthread); 803 } 804 805 /* 806 * Drain the cached buckets from a zone. Expects a locked zone on entry. 807 */ 808 static void 809 bucket_cache_drain(uma_zone_t zone) 810 { 811 uma_bucket_t bucket; 812 813 /* 814 * Drain the bucket queues and free the buckets, we just keep two per 815 * cpu (alloc/free). 816 */ 817 while ((bucket = LIST_FIRST(&zone->uz_buckets)) != NULL) { 818 LIST_REMOVE(bucket, ub_link); 819 ZONE_UNLOCK(zone); 820 bucket_drain(zone, bucket); 821 bucket_free(zone, bucket, NULL); 822 ZONE_LOCK(zone); 823 } 824 825 /* 826 * Shrink further bucket sizes. Price of single zone lock collision 827 * is probably lower then price of global cache drain. 828 */ 829 if (zone->uz_count > zone->uz_count_min) 830 zone->uz_count--; 831 } 832 833 static void 834 keg_free_slab(uma_keg_t keg, uma_slab_t slab, int start) 835 { 836 uint8_t *mem; 837 int i; 838 uint8_t flags; 839 840 CTR4(KTR_UMA, "keg_free_slab keg %s(%p) slab %p, returning %d bytes", 841 keg->uk_name, keg, slab, PAGE_SIZE * keg->uk_ppera); 842 843 mem = slab->us_data; 844 flags = slab->us_flags; 845 i = start; 846 if (keg->uk_fini != NULL) { 847 for (i--; i > -1; i--) 848 keg->uk_fini(slab->us_data + (keg->uk_rsize * i), 849 keg->uk_size); 850 } 851 if (keg->uk_flags & UMA_ZONE_OFFPAGE) 852 zone_free_item(keg->uk_slabzone, slab, NULL, SKIP_NONE); 853 keg->uk_freef(mem, PAGE_SIZE * keg->uk_ppera, flags); 854 uma_total_dec(PAGE_SIZE * keg->uk_ppera); 855 } 856 857 /* 858 * Frees pages from a keg back to the system. This is done on demand from 859 * the pageout daemon. 860 * 861 * Returns nothing. 862 */ 863 static void 864 keg_drain(uma_keg_t keg) 865 { 866 struct slabhead freeslabs = { 0 }; 867 uma_slab_t slab, tmp; 868 869 /* 870 * We don't want to take pages from statically allocated kegs at this 871 * time 872 */ 873 if (keg->uk_flags & UMA_ZONE_NOFREE || keg->uk_freef == NULL) 874 return; 875 876 CTR3(KTR_UMA, "keg_drain %s(%p) free items: %u", 877 keg->uk_name, keg, keg->uk_free); 878 KEG_LOCK(keg); 879 if (keg->uk_free == 0) 880 goto finished; 881 882 LIST_FOREACH_SAFE(slab, &keg->uk_free_slab, us_link, tmp) { 883 /* We have nowhere to free these to. */ 884 if (slab->us_flags & UMA_SLAB_BOOT) 885 continue; 886 887 LIST_REMOVE(slab, us_link); 888 keg->uk_pages -= keg->uk_ppera; 889 keg->uk_free -= keg->uk_ipers; 890 891 if (keg->uk_flags & UMA_ZONE_HASH) 892 UMA_HASH_REMOVE(&keg->uk_hash, slab, slab->us_data); 893 894 SLIST_INSERT_HEAD(&freeslabs, slab, us_hlink); 895 } 896 finished: 897 KEG_UNLOCK(keg); 898 899 while ((slab = SLIST_FIRST(&freeslabs)) != NULL) { 900 SLIST_REMOVE(&freeslabs, slab, uma_slab, us_hlink); 901 keg_free_slab(keg, slab, keg->uk_ipers); 902 } 903 } 904 905 static void 906 zone_drain_wait(uma_zone_t zone, int waitok) 907 { 908 909 /* 910 * Set draining to interlock with zone_dtor() so we can release our 911 * locks as we go. Only dtor() should do a WAITOK call since it 912 * is the only call that knows the structure will still be available 913 * when it wakes up. 914 */ 915 ZONE_LOCK(zone); 916 while (zone->uz_flags & UMA_ZFLAG_DRAINING) { 917 if (waitok == M_NOWAIT) 918 goto out; 919 msleep(zone, zone->uz_lockptr, PVM, "zonedrain", 1); 920 } 921 zone->uz_flags |= UMA_ZFLAG_DRAINING; 922 bucket_cache_drain(zone); 923 ZONE_UNLOCK(zone); 924 /* 925 * The DRAINING flag protects us from being freed while 926 * we're running. Normally the uma_rwlock would protect us but we 927 * must be able to release and acquire the right lock for each keg. 928 */ 929 zone_foreach_keg(zone, &keg_drain); 930 ZONE_LOCK(zone); 931 zone->uz_flags &= ~UMA_ZFLAG_DRAINING; 932 wakeup(zone); 933 out: 934 ZONE_UNLOCK(zone); 935 } 936 937 void 938 zone_drain(uma_zone_t zone) 939 { 940 941 zone_drain_wait(zone, M_NOWAIT); 942 } 943 944 /* 945 * Allocate a new slab for a keg. This does not insert the slab onto a list. 946 * 947 * Arguments: 948 * wait Shall we wait? 949 * 950 * Returns: 951 * The slab that was allocated or NULL if there is no memory and the 952 * caller specified M_NOWAIT. 953 */ 954 static uma_slab_t 955 keg_alloc_slab(uma_keg_t keg, uma_zone_t zone, int wait) 956 { 957 uma_alloc allocf; 958 uma_slab_t slab; 959 unsigned long size; 960 uint8_t *mem; 961 uint8_t flags; 962 int i; 963 964 mtx_assert(&keg->uk_lock, MA_OWNED); 965 slab = NULL; 966 mem = NULL; 967 968 allocf = keg->uk_allocf; 969 KEG_UNLOCK(keg); 970 size = keg->uk_ppera * PAGE_SIZE; 971 972 if (keg->uk_flags & UMA_ZONE_OFFPAGE) { 973 slab = zone_alloc_item(keg->uk_slabzone, NULL, wait); 974 if (slab == NULL) 975 goto out; 976 } 977 978 /* 979 * This reproduces the old vm_zone behavior of zero filling pages the 980 * first time they are added to a zone. 981 * 982 * Malloced items are zeroed in uma_zalloc. 983 */ 984 985 if ((keg->uk_flags & UMA_ZONE_MALLOC) == 0) 986 wait |= M_ZERO; 987 else 988 wait &= ~M_ZERO; 989 990 if (keg->uk_flags & UMA_ZONE_NODUMP) 991 wait |= M_NODUMP; 992 993 /* zone is passed for legacy reasons. */ 994 mem = allocf(zone, size, &flags, wait); 995 if (mem == NULL) { 996 if (keg->uk_flags & UMA_ZONE_OFFPAGE) 997 zone_free_item(keg->uk_slabzone, slab, NULL, SKIP_NONE); 998 slab = NULL; 999 goto out; 1000 } 1001 uma_total_inc(size); 1002 1003 /* Point the slab into the allocated memory */ 1004 if (!(keg->uk_flags & UMA_ZONE_OFFPAGE)) 1005 slab = (uma_slab_t )(mem + keg->uk_pgoff); 1006 1007 if (keg->uk_flags & UMA_ZONE_VTOSLAB) 1008 for (i = 0; i < keg->uk_ppera; i++) 1009 vsetslab((vm_offset_t)mem + (i * PAGE_SIZE), slab); 1010 1011 slab->us_keg = keg; 1012 slab->us_data = mem; 1013 slab->us_freecount = keg->uk_ipers; 1014 slab->us_flags = flags; 1015 BIT_FILL(SLAB_SETSIZE, &slab->us_free); 1016 #ifdef INVARIANTS 1017 BIT_ZERO(SLAB_SETSIZE, &slab->us_debugfree); 1018 #endif 1019 1020 if (keg->uk_init != NULL) { 1021 for (i = 0; i < keg->uk_ipers; i++) 1022 if (keg->uk_init(slab->us_data + (keg->uk_rsize * i), 1023 keg->uk_size, wait) != 0) 1024 break; 1025 if (i != keg->uk_ipers) { 1026 keg_free_slab(keg, slab, i); 1027 slab = NULL; 1028 goto out; 1029 } 1030 } 1031 out: 1032 KEG_LOCK(keg); 1033 1034 CTR3(KTR_UMA, "keg_alloc_slab: allocated slab %p for %s(%p)", 1035 slab, keg->uk_name, keg); 1036 1037 if (slab != NULL) { 1038 if (keg->uk_flags & UMA_ZONE_HASH) 1039 UMA_HASH_INSERT(&keg->uk_hash, slab, mem); 1040 1041 keg->uk_pages += keg->uk_ppera; 1042 keg->uk_free += keg->uk_ipers; 1043 } 1044 1045 return (slab); 1046 } 1047 1048 /* 1049 * This function is intended to be used early on in place of page_alloc() so 1050 * that we may use the boot time page cache to satisfy allocations before 1051 * the VM is ready. 1052 */ 1053 static void * 1054 startup_alloc(uma_zone_t zone, vm_size_t bytes, uint8_t *pflag, int wait) 1055 { 1056 uma_keg_t keg; 1057 void *mem; 1058 int pages; 1059 1060 keg = zone_first_keg(zone); 1061 pages = howmany(bytes, PAGE_SIZE); 1062 KASSERT(pages > 0, ("startup_alloc can't reserve 0 pages\n")); 1063 1064 /* 1065 * Check our small startup cache to see if it has pages remaining. 1066 */ 1067 mtx_lock(&uma_boot_pages_mtx); 1068 if (pages <= boot_pages) { 1069 mem = bootmem; 1070 boot_pages -= pages; 1071 bootmem += pages * PAGE_SIZE; 1072 mtx_unlock(&uma_boot_pages_mtx); 1073 *pflag = UMA_SLAB_BOOT; 1074 return (mem); 1075 } 1076 mtx_unlock(&uma_boot_pages_mtx); 1077 if (booted < UMA_STARTUP2) 1078 panic("UMA: Increase vm.boot_pages"); 1079 /* 1080 * Now that we've booted reset these users to their real allocator. 1081 */ 1082 #ifdef UMA_MD_SMALL_ALLOC 1083 keg->uk_allocf = (keg->uk_ppera > 1) ? page_alloc : uma_small_alloc; 1084 #else 1085 keg->uk_allocf = page_alloc; 1086 #endif 1087 return keg->uk_allocf(zone, bytes, pflag, wait); 1088 } 1089 1090 /* 1091 * Allocates a number of pages from the system 1092 * 1093 * Arguments: 1094 * bytes The number of bytes requested 1095 * wait Shall we wait? 1096 * 1097 * Returns: 1098 * A pointer to the alloced memory or possibly 1099 * NULL if M_NOWAIT is set. 1100 */ 1101 static void * 1102 page_alloc(uma_zone_t zone, vm_size_t bytes, uint8_t *pflag, int wait) 1103 { 1104 void *p; /* Returned page */ 1105 1106 *pflag = UMA_SLAB_KERNEL; 1107 p = (void *) kmem_malloc(kernel_arena, bytes, wait); 1108 1109 return (p); 1110 } 1111 1112 /* 1113 * Allocates a number of pages from within an object 1114 * 1115 * Arguments: 1116 * bytes The number of bytes requested 1117 * wait Shall we wait? 1118 * 1119 * Returns: 1120 * A pointer to the alloced memory or possibly 1121 * NULL if M_NOWAIT is set. 1122 */ 1123 static void * 1124 noobj_alloc(uma_zone_t zone, vm_size_t bytes, uint8_t *flags, int wait) 1125 { 1126 TAILQ_HEAD(, vm_page) alloctail; 1127 u_long npages; 1128 vm_offset_t retkva, zkva; 1129 vm_page_t p, p_next; 1130 uma_keg_t keg; 1131 1132 TAILQ_INIT(&alloctail); 1133 keg = zone_first_keg(zone); 1134 1135 npages = howmany(bytes, PAGE_SIZE); 1136 while (npages > 0) { 1137 p = vm_page_alloc(NULL, 0, VM_ALLOC_INTERRUPT | 1138 VM_ALLOC_WIRED | VM_ALLOC_NOOBJ | 1139 ((wait & M_WAITOK) != 0 ? VM_ALLOC_WAITOK : 1140 VM_ALLOC_NOWAIT)); 1141 if (p != NULL) { 1142 /* 1143 * Since the page does not belong to an object, its 1144 * listq is unused. 1145 */ 1146 TAILQ_INSERT_TAIL(&alloctail, p, listq); 1147 npages--; 1148 continue; 1149 } 1150 /* 1151 * Page allocation failed, free intermediate pages and 1152 * exit. 1153 */ 1154 TAILQ_FOREACH_SAFE(p, &alloctail, listq, p_next) { 1155 vm_page_unwire(p, PQ_NONE); 1156 vm_page_free(p); 1157 } 1158 return (NULL); 1159 } 1160 *flags = UMA_SLAB_PRIV; 1161 zkva = keg->uk_kva + 1162 atomic_fetchadd_long(&keg->uk_offset, round_page(bytes)); 1163 retkva = zkva; 1164 TAILQ_FOREACH(p, &alloctail, listq) { 1165 pmap_qenter(zkva, &p, 1); 1166 zkva += PAGE_SIZE; 1167 } 1168 1169 return ((void *)retkva); 1170 } 1171 1172 /* 1173 * Frees a number of pages to the system 1174 * 1175 * Arguments: 1176 * mem A pointer to the memory to be freed 1177 * size The size of the memory being freed 1178 * flags The original p->us_flags field 1179 * 1180 * Returns: 1181 * Nothing 1182 */ 1183 static void 1184 page_free(void *mem, vm_size_t size, uint8_t flags) 1185 { 1186 struct vmem *vmem; 1187 1188 if (flags & UMA_SLAB_KERNEL) 1189 vmem = kernel_arena; 1190 else 1191 panic("UMA: page_free used with invalid flags %x", flags); 1192 1193 kmem_free(vmem, (vm_offset_t)mem, size); 1194 } 1195 1196 /* 1197 * Zero fill initializer 1198 * 1199 * Arguments/Returns follow uma_init specifications 1200 */ 1201 static int 1202 zero_init(void *mem, int size, int flags) 1203 { 1204 bzero(mem, size); 1205 return (0); 1206 } 1207 1208 /* 1209 * Finish creating a small uma keg. This calculates ipers, and the keg size. 1210 * 1211 * Arguments 1212 * keg The zone we should initialize 1213 * 1214 * Returns 1215 * Nothing 1216 */ 1217 static void 1218 keg_small_init(uma_keg_t keg) 1219 { 1220 u_int rsize; 1221 u_int memused; 1222 u_int wastedspace; 1223 u_int shsize; 1224 u_int slabsize; 1225 1226 if (keg->uk_flags & UMA_ZONE_PCPU) { 1227 u_int ncpus = (mp_maxid + 1) ? (mp_maxid + 1) : MAXCPU; 1228 1229 slabsize = sizeof(struct pcpu); 1230 keg->uk_ppera = howmany(ncpus * sizeof(struct pcpu), 1231 PAGE_SIZE); 1232 } else { 1233 slabsize = UMA_SLAB_SIZE; 1234 keg->uk_ppera = 1; 1235 } 1236 1237 /* 1238 * Calculate the size of each allocation (rsize) according to 1239 * alignment. If the requested size is smaller than we have 1240 * allocation bits for we round it up. 1241 */ 1242 rsize = keg->uk_size; 1243 if (rsize < slabsize / SLAB_SETSIZE) 1244 rsize = slabsize / SLAB_SETSIZE; 1245 if (rsize & keg->uk_align) 1246 rsize = (rsize & ~keg->uk_align) + (keg->uk_align + 1); 1247 keg->uk_rsize = rsize; 1248 1249 KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0 || 1250 keg->uk_rsize < sizeof(struct pcpu), 1251 ("%s: size %u too large", __func__, keg->uk_rsize)); 1252 1253 if (keg->uk_flags & UMA_ZONE_OFFPAGE) 1254 shsize = 0; 1255 else 1256 shsize = sizeof(struct uma_slab); 1257 1258 keg->uk_ipers = (slabsize - shsize) / rsize; 1259 KASSERT(keg->uk_ipers > 0 && keg->uk_ipers <= SLAB_SETSIZE, 1260 ("%s: keg->uk_ipers %u", __func__, keg->uk_ipers)); 1261 1262 memused = keg->uk_ipers * rsize + shsize; 1263 wastedspace = slabsize - memused; 1264 1265 /* 1266 * We can't do OFFPAGE if we're internal or if we've been 1267 * asked to not go to the VM for buckets. If we do this we 1268 * may end up going to the VM for slabs which we do not 1269 * want to do if we're UMA_ZFLAG_CACHEONLY as a result 1270 * of UMA_ZONE_VM, which clearly forbids it. 1271 */ 1272 if ((keg->uk_flags & UMA_ZFLAG_INTERNAL) || 1273 (keg->uk_flags & UMA_ZFLAG_CACHEONLY)) 1274 return; 1275 1276 /* 1277 * See if using an OFFPAGE slab will limit our waste. Only do 1278 * this if it permits more items per-slab. 1279 * 1280 * XXX We could try growing slabsize to limit max waste as well. 1281 * Historically this was not done because the VM could not 1282 * efficiently handle contiguous allocations. 1283 */ 1284 if ((wastedspace >= slabsize / UMA_MAX_WASTE) && 1285 (keg->uk_ipers < (slabsize / keg->uk_rsize))) { 1286 keg->uk_ipers = slabsize / keg->uk_rsize; 1287 KASSERT(keg->uk_ipers > 0 && keg->uk_ipers <= SLAB_SETSIZE, 1288 ("%s: keg->uk_ipers %u", __func__, keg->uk_ipers)); 1289 CTR6(KTR_UMA, "UMA decided we need offpage slab headers for " 1290 "keg: %s(%p), calculated wastedspace = %d, " 1291 "maximum wasted space allowed = %d, " 1292 "calculated ipers = %d, " 1293 "new wasted space = %d\n", keg->uk_name, keg, wastedspace, 1294 slabsize / UMA_MAX_WASTE, keg->uk_ipers, 1295 slabsize - keg->uk_ipers * keg->uk_rsize); 1296 keg->uk_flags |= UMA_ZONE_OFFPAGE; 1297 } 1298 1299 if ((keg->uk_flags & UMA_ZONE_OFFPAGE) && 1300 (keg->uk_flags & UMA_ZONE_VTOSLAB) == 0) 1301 keg->uk_flags |= UMA_ZONE_HASH; 1302 } 1303 1304 /* 1305 * Finish creating a large (> UMA_SLAB_SIZE) uma kegs. Just give in and do 1306 * OFFPAGE for now. When I can allow for more dynamic slab sizes this will be 1307 * more complicated. 1308 * 1309 * Arguments 1310 * keg The keg we should initialize 1311 * 1312 * Returns 1313 * Nothing 1314 */ 1315 static void 1316 keg_large_init(uma_keg_t keg) 1317 { 1318 u_int shsize; 1319 1320 KASSERT(keg != NULL, ("Keg is null in keg_large_init")); 1321 KASSERT((keg->uk_flags & UMA_ZFLAG_CACHEONLY) == 0, 1322 ("keg_large_init: Cannot large-init a UMA_ZFLAG_CACHEONLY keg")); 1323 KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0, 1324 ("%s: Cannot large-init a UMA_ZONE_PCPU keg", __func__)); 1325 1326 keg->uk_ppera = howmany(keg->uk_size, PAGE_SIZE); 1327 keg->uk_ipers = 1; 1328 keg->uk_rsize = keg->uk_size; 1329 1330 /* Check whether we have enough space to not do OFFPAGE. */ 1331 if ((keg->uk_flags & UMA_ZONE_OFFPAGE) == 0) { 1332 shsize = sizeof(struct uma_slab); 1333 if (shsize & UMA_ALIGN_PTR) 1334 shsize = (shsize & ~UMA_ALIGN_PTR) + 1335 (UMA_ALIGN_PTR + 1); 1336 1337 if (PAGE_SIZE * keg->uk_ppera - keg->uk_rsize < shsize) { 1338 /* 1339 * We can't do OFFPAGE if we're internal, in which case 1340 * we need an extra page per allocation to contain the 1341 * slab header. 1342 */ 1343 if ((keg->uk_flags & UMA_ZFLAG_INTERNAL) == 0) 1344 keg->uk_flags |= UMA_ZONE_OFFPAGE; 1345 else 1346 keg->uk_ppera++; 1347 } 1348 } 1349 1350 if ((keg->uk_flags & UMA_ZONE_OFFPAGE) && 1351 (keg->uk_flags & UMA_ZONE_VTOSLAB) == 0) 1352 keg->uk_flags |= UMA_ZONE_HASH; 1353 } 1354 1355 static void 1356 keg_cachespread_init(uma_keg_t keg) 1357 { 1358 int alignsize; 1359 int trailer; 1360 int pages; 1361 int rsize; 1362 1363 KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0, 1364 ("%s: Cannot cachespread-init a UMA_ZONE_PCPU keg", __func__)); 1365 1366 alignsize = keg->uk_align + 1; 1367 rsize = keg->uk_size; 1368 /* 1369 * We want one item to start on every align boundary in a page. To 1370 * do this we will span pages. We will also extend the item by the 1371 * size of align if it is an even multiple of align. Otherwise, it 1372 * would fall on the same boundary every time. 1373 */ 1374 if (rsize & keg->uk_align) 1375 rsize = (rsize & ~keg->uk_align) + alignsize; 1376 if ((rsize & alignsize) == 0) 1377 rsize += alignsize; 1378 trailer = rsize - keg->uk_size; 1379 pages = (rsize * (PAGE_SIZE / alignsize)) / PAGE_SIZE; 1380 pages = MIN(pages, (128 * 1024) / PAGE_SIZE); 1381 keg->uk_rsize = rsize; 1382 keg->uk_ppera = pages; 1383 keg->uk_ipers = ((pages * PAGE_SIZE) + trailer) / rsize; 1384 keg->uk_flags |= UMA_ZONE_OFFPAGE | UMA_ZONE_VTOSLAB; 1385 KASSERT(keg->uk_ipers <= SLAB_SETSIZE, 1386 ("%s: keg->uk_ipers too high(%d) increase max_ipers", __func__, 1387 keg->uk_ipers)); 1388 } 1389 1390 /* 1391 * Keg header ctor. This initializes all fields, locks, etc. And inserts 1392 * the keg onto the global keg list. 1393 * 1394 * Arguments/Returns follow uma_ctor specifications 1395 * udata Actually uma_kctor_args 1396 */ 1397 static int 1398 keg_ctor(void *mem, int size, void *udata, int flags) 1399 { 1400 struct uma_kctor_args *arg = udata; 1401 uma_keg_t keg = mem; 1402 uma_zone_t zone; 1403 1404 bzero(keg, size); 1405 keg->uk_size = arg->size; 1406 keg->uk_init = arg->uminit; 1407 keg->uk_fini = arg->fini; 1408 keg->uk_align = arg->align; 1409 keg->uk_free = 0; 1410 keg->uk_reserve = 0; 1411 keg->uk_pages = 0; 1412 keg->uk_flags = arg->flags; 1413 keg->uk_slabzone = NULL; 1414 1415 /* 1416 * The master zone is passed to us at keg-creation time. 1417 */ 1418 zone = arg->zone; 1419 keg->uk_name = zone->uz_name; 1420 1421 if (arg->flags & UMA_ZONE_VM) 1422 keg->uk_flags |= UMA_ZFLAG_CACHEONLY; 1423 1424 if (arg->flags & UMA_ZONE_ZINIT) 1425 keg->uk_init = zero_init; 1426 1427 if (arg->flags & UMA_ZONE_MALLOC) 1428 keg->uk_flags |= UMA_ZONE_VTOSLAB; 1429 1430 if (arg->flags & UMA_ZONE_PCPU) 1431 #ifdef SMP 1432 keg->uk_flags |= UMA_ZONE_OFFPAGE; 1433 #else 1434 keg->uk_flags &= ~UMA_ZONE_PCPU; 1435 #endif 1436 1437 if (keg->uk_flags & UMA_ZONE_CACHESPREAD) { 1438 keg_cachespread_init(keg); 1439 } else { 1440 if (keg->uk_size > (UMA_SLAB_SIZE - sizeof(struct uma_slab))) 1441 keg_large_init(keg); 1442 else 1443 keg_small_init(keg); 1444 } 1445 1446 if (keg->uk_flags & UMA_ZONE_OFFPAGE) 1447 keg->uk_slabzone = slabzone; 1448 1449 /* 1450 * If we haven't booted yet we need allocations to go through the 1451 * startup cache until the vm is ready. 1452 */ 1453 if (booted < UMA_STARTUP2) 1454 keg->uk_allocf = startup_alloc; 1455 #ifdef UMA_MD_SMALL_ALLOC 1456 else if (keg->uk_ppera == 1) 1457 keg->uk_allocf = uma_small_alloc; 1458 #endif 1459 else 1460 keg->uk_allocf = page_alloc; 1461 #ifdef UMA_MD_SMALL_ALLOC 1462 if (keg->uk_ppera == 1) 1463 keg->uk_freef = uma_small_free; 1464 else 1465 #endif 1466 keg->uk_freef = page_free; 1467 1468 /* 1469 * Initialize keg's lock 1470 */ 1471 KEG_LOCK_INIT(keg, (arg->flags & UMA_ZONE_MTXCLASS)); 1472 1473 /* 1474 * If we're putting the slab header in the actual page we need to 1475 * figure out where in each page it goes. This calculates a right 1476 * justified offset into the memory on an ALIGN_PTR boundary. 1477 */ 1478 if (!(keg->uk_flags & UMA_ZONE_OFFPAGE)) { 1479 u_int totsize; 1480 1481 /* Size of the slab struct and free list */ 1482 totsize = sizeof(struct uma_slab); 1483 1484 if (totsize & UMA_ALIGN_PTR) 1485 totsize = (totsize & ~UMA_ALIGN_PTR) + 1486 (UMA_ALIGN_PTR + 1); 1487 keg->uk_pgoff = (PAGE_SIZE * keg->uk_ppera) - totsize; 1488 1489 /* 1490 * The only way the following is possible is if with our 1491 * UMA_ALIGN_PTR adjustments we are now bigger than 1492 * UMA_SLAB_SIZE. I haven't checked whether this is 1493 * mathematically possible for all cases, so we make 1494 * sure here anyway. 1495 */ 1496 totsize = keg->uk_pgoff + sizeof(struct uma_slab); 1497 if (totsize > PAGE_SIZE * keg->uk_ppera) { 1498 printf("zone %s ipers %d rsize %d size %d\n", 1499 zone->uz_name, keg->uk_ipers, keg->uk_rsize, 1500 keg->uk_size); 1501 panic("UMA slab won't fit."); 1502 } 1503 } 1504 1505 if (keg->uk_flags & UMA_ZONE_HASH) 1506 hash_alloc(&keg->uk_hash); 1507 1508 CTR5(KTR_UMA, "keg_ctor %p zone %s(%p) out %d free %d\n", 1509 keg, zone->uz_name, zone, 1510 (keg->uk_pages / keg->uk_ppera) * keg->uk_ipers - keg->uk_free, 1511 keg->uk_free); 1512 1513 LIST_INSERT_HEAD(&keg->uk_zones, zone, uz_link); 1514 1515 rw_wlock(&uma_rwlock); 1516 LIST_INSERT_HEAD(&uma_kegs, keg, uk_link); 1517 rw_wunlock(&uma_rwlock); 1518 return (0); 1519 } 1520 1521 /* 1522 * Zone header ctor. This initializes all fields, locks, etc. 1523 * 1524 * Arguments/Returns follow uma_ctor specifications 1525 * udata Actually uma_zctor_args 1526 */ 1527 static int 1528 zone_ctor(void *mem, int size, void *udata, int flags) 1529 { 1530 struct uma_zctor_args *arg = udata; 1531 uma_zone_t zone = mem; 1532 uma_zone_t z; 1533 uma_keg_t keg; 1534 1535 bzero(zone, size); 1536 zone->uz_name = arg->name; 1537 zone->uz_ctor = arg->ctor; 1538 zone->uz_dtor = arg->dtor; 1539 zone->uz_slab = zone_fetch_slab; 1540 zone->uz_init = NULL; 1541 zone->uz_fini = NULL; 1542 zone->uz_allocs = 0; 1543 zone->uz_frees = 0; 1544 zone->uz_fails = 0; 1545 zone->uz_sleeps = 0; 1546 zone->uz_count = 0; 1547 zone->uz_count_min = 0; 1548 zone->uz_flags = 0; 1549 zone->uz_warning = NULL; 1550 timevalclear(&zone->uz_ratecheck); 1551 keg = arg->keg; 1552 1553 ZONE_LOCK_INIT(zone, (arg->flags & UMA_ZONE_MTXCLASS)); 1554 1555 /* 1556 * This is a pure cache zone, no kegs. 1557 */ 1558 if (arg->import) { 1559 if (arg->flags & UMA_ZONE_VM) 1560 arg->flags |= UMA_ZFLAG_CACHEONLY; 1561 zone->uz_flags = arg->flags; 1562 zone->uz_size = arg->size; 1563 zone->uz_import = arg->import; 1564 zone->uz_release = arg->release; 1565 zone->uz_arg = arg->arg; 1566 zone->uz_lockptr = &zone->uz_lock; 1567 rw_wlock(&uma_rwlock); 1568 LIST_INSERT_HEAD(&uma_cachezones, zone, uz_link); 1569 rw_wunlock(&uma_rwlock); 1570 goto out; 1571 } 1572 1573 /* 1574 * Use the regular zone/keg/slab allocator. 1575 */ 1576 zone->uz_import = (uma_import)zone_import; 1577 zone->uz_release = (uma_release)zone_release; 1578 zone->uz_arg = zone; 1579 1580 if (arg->flags & UMA_ZONE_SECONDARY) { 1581 KASSERT(arg->keg != NULL, ("Secondary zone on zero'd keg")); 1582 zone->uz_init = arg->uminit; 1583 zone->uz_fini = arg->fini; 1584 zone->uz_lockptr = &keg->uk_lock; 1585 zone->uz_flags |= UMA_ZONE_SECONDARY; 1586 rw_wlock(&uma_rwlock); 1587 ZONE_LOCK(zone); 1588 LIST_FOREACH(z, &keg->uk_zones, uz_link) { 1589 if (LIST_NEXT(z, uz_link) == NULL) { 1590 LIST_INSERT_AFTER(z, zone, uz_link); 1591 break; 1592 } 1593 } 1594 ZONE_UNLOCK(zone); 1595 rw_wunlock(&uma_rwlock); 1596 } else if (keg == NULL) { 1597 if ((keg = uma_kcreate(zone, arg->size, arg->uminit, arg->fini, 1598 arg->align, arg->flags)) == NULL) 1599 return (ENOMEM); 1600 } else { 1601 struct uma_kctor_args karg; 1602 int error; 1603 1604 /* We should only be here from uma_startup() */ 1605 karg.size = arg->size; 1606 karg.uminit = arg->uminit; 1607 karg.fini = arg->fini; 1608 karg.align = arg->align; 1609 karg.flags = arg->flags; 1610 karg.zone = zone; 1611 error = keg_ctor(arg->keg, sizeof(struct uma_keg), &karg, 1612 flags); 1613 if (error) 1614 return (error); 1615 } 1616 1617 /* 1618 * Link in the first keg. 1619 */ 1620 zone->uz_klink.kl_keg = keg; 1621 LIST_INSERT_HEAD(&zone->uz_kegs, &zone->uz_klink, kl_link); 1622 zone->uz_lockptr = &keg->uk_lock; 1623 zone->uz_size = keg->uk_size; 1624 zone->uz_flags |= (keg->uk_flags & 1625 (UMA_ZONE_INHERIT | UMA_ZFLAG_INHERIT)); 1626 1627 /* 1628 * Some internal zones don't have room allocated for the per cpu 1629 * caches. If we're internal, bail out here. 1630 */ 1631 if (keg->uk_flags & UMA_ZFLAG_INTERNAL) { 1632 KASSERT((zone->uz_flags & UMA_ZONE_SECONDARY) == 0, 1633 ("Secondary zone requested UMA_ZFLAG_INTERNAL")); 1634 return (0); 1635 } 1636 1637 out: 1638 if ((arg->flags & UMA_ZONE_MAXBUCKET) == 0) 1639 zone->uz_count = bucket_select(zone->uz_size); 1640 else 1641 zone->uz_count = BUCKET_MAX; 1642 zone->uz_count_min = zone->uz_count; 1643 1644 return (0); 1645 } 1646 1647 /* 1648 * Keg header dtor. This frees all data, destroys locks, frees the hash 1649 * table and removes the keg from the global list. 1650 * 1651 * Arguments/Returns follow uma_dtor specifications 1652 * udata unused 1653 */ 1654 static void 1655 keg_dtor(void *arg, int size, void *udata) 1656 { 1657 uma_keg_t keg; 1658 1659 keg = (uma_keg_t)arg; 1660 KEG_LOCK(keg); 1661 if (keg->uk_free != 0) { 1662 printf("Freed UMA keg (%s) was not empty (%d items). " 1663 " Lost %d pages of memory.\n", 1664 keg->uk_name ? keg->uk_name : "", 1665 keg->uk_free, keg->uk_pages); 1666 } 1667 KEG_UNLOCK(keg); 1668 1669 hash_free(&keg->uk_hash); 1670 1671 KEG_LOCK_FINI(keg); 1672 } 1673 1674 /* 1675 * Zone header dtor. 1676 * 1677 * Arguments/Returns follow uma_dtor specifications 1678 * udata unused 1679 */ 1680 static void 1681 zone_dtor(void *arg, int size, void *udata) 1682 { 1683 uma_klink_t klink; 1684 uma_zone_t zone; 1685 uma_keg_t keg; 1686 1687 zone = (uma_zone_t)arg; 1688 keg = zone_first_keg(zone); 1689 1690 if (!(zone->uz_flags & UMA_ZFLAG_INTERNAL)) 1691 cache_drain(zone); 1692 1693 rw_wlock(&uma_rwlock); 1694 LIST_REMOVE(zone, uz_link); 1695 rw_wunlock(&uma_rwlock); 1696 /* 1697 * XXX there are some races here where 1698 * the zone can be drained but zone lock 1699 * released and then refilled before we 1700 * remove it... we dont care for now 1701 */ 1702 zone_drain_wait(zone, M_WAITOK); 1703 /* 1704 * Unlink all of our kegs. 1705 */ 1706 while ((klink = LIST_FIRST(&zone->uz_kegs)) != NULL) { 1707 klink->kl_keg = NULL; 1708 LIST_REMOVE(klink, kl_link); 1709 if (klink == &zone->uz_klink) 1710 continue; 1711 free(klink, M_TEMP); 1712 } 1713 /* 1714 * We only destroy kegs from non secondary zones. 1715 */ 1716 if (keg != NULL && (zone->uz_flags & UMA_ZONE_SECONDARY) == 0) { 1717 rw_wlock(&uma_rwlock); 1718 LIST_REMOVE(keg, uk_link); 1719 rw_wunlock(&uma_rwlock); 1720 zone_free_item(kegs, keg, NULL, SKIP_NONE); 1721 } 1722 ZONE_LOCK_FINI(zone); 1723 } 1724 1725 /* 1726 * Traverses every zone in the system and calls a callback 1727 * 1728 * Arguments: 1729 * zfunc A pointer to a function which accepts a zone 1730 * as an argument. 1731 * 1732 * Returns: 1733 * Nothing 1734 */ 1735 static void 1736 zone_foreach(void (*zfunc)(uma_zone_t)) 1737 { 1738 uma_keg_t keg; 1739 uma_zone_t zone; 1740 1741 rw_rlock(&uma_rwlock); 1742 LIST_FOREACH(keg, &uma_kegs, uk_link) { 1743 LIST_FOREACH(zone, &keg->uk_zones, uz_link) 1744 zfunc(zone); 1745 } 1746 rw_runlock(&uma_rwlock); 1747 } 1748 1749 /* Public functions */ 1750 /* See uma.h */ 1751 void 1752 uma_startup(void *mem, int npages) 1753 { 1754 struct uma_zctor_args args; 1755 1756 rw_init(&uma_rwlock, "UMA lock"); 1757 1758 /* "manually" create the initial zone */ 1759 memset(&args, 0, sizeof(args)); 1760 args.name = "UMA Kegs"; 1761 args.size = sizeof(struct uma_keg); 1762 args.ctor = keg_ctor; 1763 args.dtor = keg_dtor; 1764 args.uminit = zero_init; 1765 args.fini = NULL; 1766 args.keg = &masterkeg; 1767 args.align = 32 - 1; 1768 args.flags = UMA_ZFLAG_INTERNAL; 1769 /* The initial zone has no Per cpu queues so it's smaller */ 1770 zone_ctor(kegs, sizeof(struct uma_zone), &args, M_WAITOK); 1771 1772 mtx_init(&uma_boot_pages_mtx, "UMA boot pages", NULL, MTX_DEF); 1773 bootmem = mem; 1774 boot_pages = npages; 1775 1776 args.name = "UMA Zones"; 1777 args.size = sizeof(struct uma_zone) + 1778 (sizeof(struct uma_cache) * (mp_maxid + 1)); 1779 args.ctor = zone_ctor; 1780 args.dtor = zone_dtor; 1781 args.uminit = zero_init; 1782 args.fini = NULL; 1783 args.keg = NULL; 1784 args.align = 32 - 1; 1785 args.flags = UMA_ZFLAG_INTERNAL; 1786 /* The initial zone has no Per cpu queues so it's smaller */ 1787 zone_ctor(zones, sizeof(struct uma_zone), &args, M_WAITOK); 1788 1789 /* Now make a zone for slab headers */ 1790 slabzone = uma_zcreate("UMA Slabs", 1791 sizeof(struct uma_slab), 1792 NULL, NULL, NULL, NULL, 1793 UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL); 1794 1795 hashzone = uma_zcreate("UMA Hash", 1796 sizeof(struct slabhead *) * UMA_HASH_SIZE_INIT, 1797 NULL, NULL, NULL, NULL, 1798 UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL); 1799 1800 bucket_init(); 1801 1802 booted = UMA_STARTUP; 1803 } 1804 1805 /* see uma.h */ 1806 void 1807 uma_startup2(void) 1808 { 1809 booted = UMA_STARTUP2; 1810 bucket_enable(); 1811 sx_init(&uma_drain_lock, "umadrain"); 1812 } 1813 1814 /* 1815 * Initialize our callout handle 1816 * 1817 */ 1818 1819 static void 1820 uma_startup3(void) 1821 { 1822 1823 callout_init(&uma_callout, 1); 1824 callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL); 1825 } 1826 1827 static uma_keg_t 1828 uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit, uma_fini fini, 1829 int align, uint32_t flags) 1830 { 1831 struct uma_kctor_args args; 1832 1833 args.size = size; 1834 args.uminit = uminit; 1835 args.fini = fini; 1836 args.align = (align == UMA_ALIGN_CACHE) ? uma_align_cache : align; 1837 args.flags = flags; 1838 args.zone = zone; 1839 return (zone_alloc_item(kegs, &args, M_WAITOK)); 1840 } 1841 1842 /* See uma.h */ 1843 void 1844 uma_set_align(int align) 1845 { 1846 1847 if (align != UMA_ALIGN_CACHE) 1848 uma_align_cache = align; 1849 } 1850 1851 /* See uma.h */ 1852 uma_zone_t 1853 uma_zcreate(const char *name, size_t size, uma_ctor ctor, uma_dtor dtor, 1854 uma_init uminit, uma_fini fini, int align, uint32_t flags) 1855 1856 { 1857 struct uma_zctor_args args; 1858 uma_zone_t res; 1859 bool locked; 1860 1861 KASSERT(powerof2(align + 1), ("invalid zone alignment %d for \"%s\"", 1862 align, name)); 1863 1864 /* This stuff is essential for the zone ctor */ 1865 memset(&args, 0, sizeof(args)); 1866 args.name = name; 1867 args.size = size; 1868 args.ctor = ctor; 1869 args.dtor = dtor; 1870 args.uminit = uminit; 1871 args.fini = fini; 1872 #ifdef INVARIANTS 1873 /* 1874 * If a zone is being created with an empty constructor and 1875 * destructor, pass UMA constructor/destructor which checks for 1876 * memory use after free. 1877 */ 1878 if ((!(flags & (UMA_ZONE_ZINIT | UMA_ZONE_NOFREE))) && 1879 ctor == NULL && dtor == NULL && uminit == NULL && fini == NULL) { 1880 args.ctor = trash_ctor; 1881 args.dtor = trash_dtor; 1882 args.uminit = trash_init; 1883 args.fini = trash_fini; 1884 } 1885 #endif 1886 args.align = align; 1887 args.flags = flags; 1888 args.keg = NULL; 1889 1890 if (booted < UMA_STARTUP2) { 1891 locked = false; 1892 } else { 1893 sx_slock(&uma_drain_lock); 1894 locked = true; 1895 } 1896 res = zone_alloc_item(zones, &args, M_WAITOK); 1897 if (locked) 1898 sx_sunlock(&uma_drain_lock); 1899 return (res); 1900 } 1901 1902 /* See uma.h */ 1903 uma_zone_t 1904 uma_zsecond_create(char *name, uma_ctor ctor, uma_dtor dtor, 1905 uma_init zinit, uma_fini zfini, uma_zone_t master) 1906 { 1907 struct uma_zctor_args args; 1908 uma_keg_t keg; 1909 uma_zone_t res; 1910 bool locked; 1911 1912 keg = zone_first_keg(master); 1913 memset(&args, 0, sizeof(args)); 1914 args.name = name; 1915 args.size = keg->uk_size; 1916 args.ctor = ctor; 1917 args.dtor = dtor; 1918 args.uminit = zinit; 1919 args.fini = zfini; 1920 args.align = keg->uk_align; 1921 args.flags = keg->uk_flags | UMA_ZONE_SECONDARY; 1922 args.keg = keg; 1923 1924 if (booted < UMA_STARTUP2) { 1925 locked = false; 1926 } else { 1927 sx_slock(&uma_drain_lock); 1928 locked = true; 1929 } 1930 /* XXX Attaches only one keg of potentially many. */ 1931 res = zone_alloc_item(zones, &args, M_WAITOK); 1932 if (locked) 1933 sx_sunlock(&uma_drain_lock); 1934 return (res); 1935 } 1936 1937 /* See uma.h */ 1938 uma_zone_t 1939 uma_zcache_create(char *name, int size, uma_ctor ctor, uma_dtor dtor, 1940 uma_init zinit, uma_fini zfini, uma_import zimport, 1941 uma_release zrelease, void *arg, int flags) 1942 { 1943 struct uma_zctor_args args; 1944 1945 memset(&args, 0, sizeof(args)); 1946 args.name = name; 1947 args.size = size; 1948 args.ctor = ctor; 1949 args.dtor = dtor; 1950 args.uminit = zinit; 1951 args.fini = zfini; 1952 args.import = zimport; 1953 args.release = zrelease; 1954 args.arg = arg; 1955 args.align = 0; 1956 args.flags = flags; 1957 1958 return (zone_alloc_item(zones, &args, M_WAITOK)); 1959 } 1960 1961 static void 1962 zone_lock_pair(uma_zone_t a, uma_zone_t b) 1963 { 1964 if (a < b) { 1965 ZONE_LOCK(a); 1966 mtx_lock_flags(b->uz_lockptr, MTX_DUPOK); 1967 } else { 1968 ZONE_LOCK(b); 1969 mtx_lock_flags(a->uz_lockptr, MTX_DUPOK); 1970 } 1971 } 1972 1973 static void 1974 zone_unlock_pair(uma_zone_t a, uma_zone_t b) 1975 { 1976 1977 ZONE_UNLOCK(a); 1978 ZONE_UNLOCK(b); 1979 } 1980 1981 int 1982 uma_zsecond_add(uma_zone_t zone, uma_zone_t master) 1983 { 1984 uma_klink_t klink; 1985 uma_klink_t kl; 1986 int error; 1987 1988 error = 0; 1989 klink = malloc(sizeof(*klink), M_TEMP, M_WAITOK | M_ZERO); 1990 1991 zone_lock_pair(zone, master); 1992 /* 1993 * zone must use vtoslab() to resolve objects and must already be 1994 * a secondary. 1995 */ 1996 if ((zone->uz_flags & (UMA_ZONE_VTOSLAB | UMA_ZONE_SECONDARY)) 1997 != (UMA_ZONE_VTOSLAB | UMA_ZONE_SECONDARY)) { 1998 error = EINVAL; 1999 goto out; 2000 } 2001 /* 2002 * The new master must also use vtoslab(). 2003 */ 2004 if ((zone->uz_flags & UMA_ZONE_VTOSLAB) != UMA_ZONE_VTOSLAB) { 2005 error = EINVAL; 2006 goto out; 2007 } 2008 2009 /* 2010 * The underlying object must be the same size. rsize 2011 * may be different. 2012 */ 2013 if (master->uz_size != zone->uz_size) { 2014 error = E2BIG; 2015 goto out; 2016 } 2017 /* 2018 * Put it at the end of the list. 2019 */ 2020 klink->kl_keg = zone_first_keg(master); 2021 LIST_FOREACH(kl, &zone->uz_kegs, kl_link) { 2022 if (LIST_NEXT(kl, kl_link) == NULL) { 2023 LIST_INSERT_AFTER(kl, klink, kl_link); 2024 break; 2025 } 2026 } 2027 klink = NULL; 2028 zone->uz_flags |= UMA_ZFLAG_MULTI; 2029 zone->uz_slab = zone_fetch_slab_multi; 2030 2031 out: 2032 zone_unlock_pair(zone, master); 2033 if (klink != NULL) 2034 free(klink, M_TEMP); 2035 2036 return (error); 2037 } 2038 2039 2040 /* See uma.h */ 2041 void 2042 uma_zdestroy(uma_zone_t zone) 2043 { 2044 2045 sx_slock(&uma_drain_lock); 2046 zone_free_item(zones, zone, NULL, SKIP_NONE); 2047 sx_sunlock(&uma_drain_lock); 2048 } 2049 2050 void 2051 uma_zwait(uma_zone_t zone) 2052 { 2053 void *item; 2054 2055 item = uma_zalloc_arg(zone, NULL, M_WAITOK); 2056 uma_zfree(zone, item); 2057 } 2058 2059 /* See uma.h */ 2060 void * 2061 uma_zalloc_arg(uma_zone_t zone, void *udata, int flags) 2062 { 2063 void *item; 2064 uma_cache_t cache; 2065 uma_bucket_t bucket; 2066 int lockfail; 2067 int cpu; 2068 2069 /* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */ 2070 random_harvest_fast_uma(&zone, sizeof(zone), 1, RANDOM_UMA); 2071 2072 /* This is the fast path allocation */ 2073 CTR4(KTR_UMA, "uma_zalloc_arg thread %x zone %s(%p) flags %d", 2074 curthread, zone->uz_name, zone, flags); 2075 2076 if (flags & M_WAITOK) { 2077 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, 2078 "uma_zalloc_arg: zone \"%s\"", zone->uz_name); 2079 } 2080 KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(), 2081 ("uma_zalloc_arg: called with spinlock or critical section held")); 2082 2083 #ifdef DEBUG_MEMGUARD 2084 if (memguard_cmp_zone(zone)) { 2085 item = memguard_alloc(zone->uz_size, flags); 2086 if (item != NULL) { 2087 if (zone->uz_init != NULL && 2088 zone->uz_init(item, zone->uz_size, flags) != 0) 2089 return (NULL); 2090 if (zone->uz_ctor != NULL && 2091 zone->uz_ctor(item, zone->uz_size, udata, 2092 flags) != 0) { 2093 zone->uz_fini(item, zone->uz_size); 2094 return (NULL); 2095 } 2096 return (item); 2097 } 2098 /* This is unfortunate but should not be fatal. */ 2099 } 2100 #endif 2101 /* 2102 * If possible, allocate from the per-CPU cache. There are two 2103 * requirements for safe access to the per-CPU cache: (1) the thread 2104 * accessing the cache must not be preempted or yield during access, 2105 * and (2) the thread must not migrate CPUs without switching which 2106 * cache it accesses. We rely on a critical section to prevent 2107 * preemption and migration. We release the critical section in 2108 * order to acquire the zone mutex if we are unable to allocate from 2109 * the current cache; when we re-acquire the critical section, we 2110 * must detect and handle migration if it has occurred. 2111 */ 2112 critical_enter(); 2113 cpu = curcpu; 2114 cache = &zone->uz_cpu[cpu]; 2115 2116 zalloc_start: 2117 bucket = cache->uc_allocbucket; 2118 if (bucket != NULL && bucket->ub_cnt > 0) { 2119 bucket->ub_cnt--; 2120 item = bucket->ub_bucket[bucket->ub_cnt]; 2121 #ifdef INVARIANTS 2122 bucket->ub_bucket[bucket->ub_cnt] = NULL; 2123 #endif 2124 KASSERT(item != NULL, ("uma_zalloc: Bucket pointer mangled.")); 2125 cache->uc_allocs++; 2126 critical_exit(); 2127 if (zone->uz_ctor != NULL && 2128 zone->uz_ctor(item, zone->uz_size, udata, flags) != 0) { 2129 atomic_add_long(&zone->uz_fails, 1); 2130 zone_free_item(zone, item, udata, SKIP_DTOR); 2131 return (NULL); 2132 } 2133 #ifdef INVARIANTS 2134 uma_dbg_alloc(zone, NULL, item); 2135 #endif 2136 if (flags & M_ZERO) 2137 uma_zero_item(item, zone); 2138 return (item); 2139 } 2140 2141 /* 2142 * We have run out of items in our alloc bucket. 2143 * See if we can switch with our free bucket. 2144 */ 2145 bucket = cache->uc_freebucket; 2146 if (bucket != NULL && bucket->ub_cnt > 0) { 2147 CTR2(KTR_UMA, 2148 "uma_zalloc: zone %s(%p) swapping empty with alloc", 2149 zone->uz_name, zone); 2150 cache->uc_freebucket = cache->uc_allocbucket; 2151 cache->uc_allocbucket = bucket; 2152 goto zalloc_start; 2153 } 2154 2155 /* 2156 * Discard any empty allocation bucket while we hold no locks. 2157 */ 2158 bucket = cache->uc_allocbucket; 2159 cache->uc_allocbucket = NULL; 2160 critical_exit(); 2161 if (bucket != NULL) 2162 bucket_free(zone, bucket, udata); 2163 2164 /* Short-circuit for zones without buckets and low memory. */ 2165 if (zone->uz_count == 0 || bucketdisable) 2166 goto zalloc_item; 2167 2168 /* 2169 * Attempt to retrieve the item from the per-CPU cache has failed, so 2170 * we must go back to the zone. This requires the zone lock, so we 2171 * must drop the critical section, then re-acquire it when we go back 2172 * to the cache. Since the critical section is released, we may be 2173 * preempted or migrate. As such, make sure not to maintain any 2174 * thread-local state specific to the cache from prior to releasing 2175 * the critical section. 2176 */ 2177 lockfail = 0; 2178 if (ZONE_TRYLOCK(zone) == 0) { 2179 /* Record contention to size the buckets. */ 2180 ZONE_LOCK(zone); 2181 lockfail = 1; 2182 } 2183 critical_enter(); 2184 cpu = curcpu; 2185 cache = &zone->uz_cpu[cpu]; 2186 2187 /* 2188 * Since we have locked the zone we may as well send back our stats. 2189 */ 2190 atomic_add_long(&zone->uz_allocs, cache->uc_allocs); 2191 atomic_add_long(&zone->uz_frees, cache->uc_frees); 2192 cache->uc_allocs = 0; 2193 cache->uc_frees = 0; 2194 2195 /* See if we lost the race to fill the cache. */ 2196 if (cache->uc_allocbucket != NULL) { 2197 ZONE_UNLOCK(zone); 2198 goto zalloc_start; 2199 } 2200 2201 /* 2202 * Check the zone's cache of buckets. 2203 */ 2204 if ((bucket = LIST_FIRST(&zone->uz_buckets)) != NULL) { 2205 KASSERT(bucket->ub_cnt != 0, 2206 ("uma_zalloc_arg: Returning an empty bucket.")); 2207 2208 LIST_REMOVE(bucket, ub_link); 2209 cache->uc_allocbucket = bucket; 2210 ZONE_UNLOCK(zone); 2211 goto zalloc_start; 2212 } 2213 /* We are no longer associated with this CPU. */ 2214 critical_exit(); 2215 2216 /* 2217 * We bump the uz count when the cache size is insufficient to 2218 * handle the working set. 2219 */ 2220 if (lockfail && zone->uz_count < BUCKET_MAX) 2221 zone->uz_count++; 2222 ZONE_UNLOCK(zone); 2223 2224 /* 2225 * Now lets just fill a bucket and put it on the free list. If that 2226 * works we'll restart the allocation from the beginning and it 2227 * will use the just filled bucket. 2228 */ 2229 bucket = zone_alloc_bucket(zone, udata, flags); 2230 CTR3(KTR_UMA, "uma_zalloc: zone %s(%p) bucket zone returned %p", 2231 zone->uz_name, zone, bucket); 2232 if (bucket != NULL) { 2233 ZONE_LOCK(zone); 2234 critical_enter(); 2235 cpu = curcpu; 2236 cache = &zone->uz_cpu[cpu]; 2237 /* 2238 * See if we lost the race or were migrated. Cache the 2239 * initialized bucket to make this less likely or claim 2240 * the memory directly. 2241 */ 2242 if (cache->uc_allocbucket == NULL) 2243 cache->uc_allocbucket = bucket; 2244 else 2245 LIST_INSERT_HEAD(&zone->uz_buckets, bucket, ub_link); 2246 ZONE_UNLOCK(zone); 2247 goto zalloc_start; 2248 } 2249 2250 /* 2251 * We may not be able to get a bucket so return an actual item. 2252 */ 2253 zalloc_item: 2254 item = zone_alloc_item(zone, udata, flags); 2255 2256 return (item); 2257 } 2258 2259 static uma_slab_t 2260 keg_fetch_slab(uma_keg_t keg, uma_zone_t zone, int flags) 2261 { 2262 uma_slab_t slab; 2263 int reserve; 2264 2265 mtx_assert(&keg->uk_lock, MA_OWNED); 2266 slab = NULL; 2267 reserve = 0; 2268 if ((flags & M_USE_RESERVE) == 0) 2269 reserve = keg->uk_reserve; 2270 2271 for (;;) { 2272 /* 2273 * Find a slab with some space. Prefer slabs that are partially 2274 * used over those that are totally full. This helps to reduce 2275 * fragmentation. 2276 */ 2277 if (keg->uk_free > reserve) { 2278 if (!LIST_EMPTY(&keg->uk_part_slab)) { 2279 slab = LIST_FIRST(&keg->uk_part_slab); 2280 } else { 2281 slab = LIST_FIRST(&keg->uk_free_slab); 2282 LIST_REMOVE(slab, us_link); 2283 LIST_INSERT_HEAD(&keg->uk_part_slab, slab, 2284 us_link); 2285 } 2286 MPASS(slab->us_keg == keg); 2287 return (slab); 2288 } 2289 2290 /* 2291 * M_NOVM means don't ask at all! 2292 */ 2293 if (flags & M_NOVM) 2294 break; 2295 2296 if (keg->uk_maxpages && keg->uk_pages >= keg->uk_maxpages) { 2297 keg->uk_flags |= UMA_ZFLAG_FULL; 2298 /* 2299 * If this is not a multi-zone, set the FULL bit. 2300 * Otherwise slab_multi() takes care of it. 2301 */ 2302 if ((zone->uz_flags & UMA_ZFLAG_MULTI) == 0) { 2303 zone->uz_flags |= UMA_ZFLAG_FULL; 2304 zone_log_warning(zone); 2305 zone_maxaction(zone); 2306 } 2307 if (flags & M_NOWAIT) 2308 break; 2309 zone->uz_sleeps++; 2310 msleep(keg, &keg->uk_lock, PVM, "keglimit", 0); 2311 continue; 2312 } 2313 slab = keg_alloc_slab(keg, zone, flags); 2314 /* 2315 * If we got a slab here it's safe to mark it partially used 2316 * and return. We assume that the caller is going to remove 2317 * at least one item. 2318 */ 2319 if (slab) { 2320 MPASS(slab->us_keg == keg); 2321 LIST_INSERT_HEAD(&keg->uk_part_slab, slab, us_link); 2322 return (slab); 2323 } 2324 /* 2325 * We might not have been able to get a slab but another cpu 2326 * could have while we were unlocked. Check again before we 2327 * fail. 2328 */ 2329 flags |= M_NOVM; 2330 } 2331 return (slab); 2332 } 2333 2334 static uma_slab_t 2335 zone_fetch_slab(uma_zone_t zone, uma_keg_t keg, int flags) 2336 { 2337 uma_slab_t slab; 2338 2339 if (keg == NULL) { 2340 keg = zone_first_keg(zone); 2341 KEG_LOCK(keg); 2342 } 2343 2344 for (;;) { 2345 slab = keg_fetch_slab(keg, zone, flags); 2346 if (slab) 2347 return (slab); 2348 if (flags & (M_NOWAIT | M_NOVM)) 2349 break; 2350 } 2351 KEG_UNLOCK(keg); 2352 return (NULL); 2353 } 2354 2355 /* 2356 * uma_zone_fetch_slab_multi: Fetches a slab from one available keg. Returns 2357 * with the keg locked. On NULL no lock is held. 2358 * 2359 * The last pointer is used to seed the search. It is not required. 2360 */ 2361 static uma_slab_t 2362 zone_fetch_slab_multi(uma_zone_t zone, uma_keg_t last, int rflags) 2363 { 2364 uma_klink_t klink; 2365 uma_slab_t slab; 2366 uma_keg_t keg; 2367 int flags; 2368 int empty; 2369 int full; 2370 2371 /* 2372 * Don't wait on the first pass. This will skip limit tests 2373 * as well. We don't want to block if we can find a provider 2374 * without blocking. 2375 */ 2376 flags = (rflags & ~M_WAITOK) | M_NOWAIT; 2377 /* 2378 * Use the last slab allocated as a hint for where to start 2379 * the search. 2380 */ 2381 if (last != NULL) { 2382 slab = keg_fetch_slab(last, zone, flags); 2383 if (slab) 2384 return (slab); 2385 KEG_UNLOCK(last); 2386 } 2387 /* 2388 * Loop until we have a slab incase of transient failures 2389 * while M_WAITOK is specified. I'm not sure this is 100% 2390 * required but we've done it for so long now. 2391 */ 2392 for (;;) { 2393 empty = 0; 2394 full = 0; 2395 /* 2396 * Search the available kegs for slabs. Be careful to hold the 2397 * correct lock while calling into the keg layer. 2398 */ 2399 LIST_FOREACH(klink, &zone->uz_kegs, kl_link) { 2400 keg = klink->kl_keg; 2401 KEG_LOCK(keg); 2402 if ((keg->uk_flags & UMA_ZFLAG_FULL) == 0) { 2403 slab = keg_fetch_slab(keg, zone, flags); 2404 if (slab) 2405 return (slab); 2406 } 2407 if (keg->uk_flags & UMA_ZFLAG_FULL) 2408 full++; 2409 else 2410 empty++; 2411 KEG_UNLOCK(keg); 2412 } 2413 if (rflags & (M_NOWAIT | M_NOVM)) 2414 break; 2415 flags = rflags; 2416 /* 2417 * All kegs are full. XXX We can't atomically check all kegs 2418 * and sleep so just sleep for a short period and retry. 2419 */ 2420 if (full && !empty) { 2421 ZONE_LOCK(zone); 2422 zone->uz_flags |= UMA_ZFLAG_FULL; 2423 zone->uz_sleeps++; 2424 zone_log_warning(zone); 2425 zone_maxaction(zone); 2426 msleep(zone, zone->uz_lockptr, PVM, 2427 "zonelimit", hz/100); 2428 zone->uz_flags &= ~UMA_ZFLAG_FULL; 2429 ZONE_UNLOCK(zone); 2430 continue; 2431 } 2432 } 2433 return (NULL); 2434 } 2435 2436 static void * 2437 slab_alloc_item(uma_keg_t keg, uma_slab_t slab) 2438 { 2439 void *item; 2440 uint8_t freei; 2441 2442 MPASS(keg == slab->us_keg); 2443 mtx_assert(&keg->uk_lock, MA_OWNED); 2444 2445 freei = BIT_FFS(SLAB_SETSIZE, &slab->us_free) - 1; 2446 BIT_CLR(SLAB_SETSIZE, freei, &slab->us_free); 2447 item = slab->us_data + (keg->uk_rsize * freei); 2448 slab->us_freecount--; 2449 keg->uk_free--; 2450 2451 /* Move this slab to the full list */ 2452 if (slab->us_freecount == 0) { 2453 LIST_REMOVE(slab, us_link); 2454 LIST_INSERT_HEAD(&keg->uk_full_slab, slab, us_link); 2455 } 2456 2457 return (item); 2458 } 2459 2460 static int 2461 zone_import(uma_zone_t zone, void **bucket, int max, int flags) 2462 { 2463 uma_slab_t slab; 2464 uma_keg_t keg; 2465 int i; 2466 2467 slab = NULL; 2468 keg = NULL; 2469 /* Try to keep the buckets totally full */ 2470 for (i = 0; i < max; ) { 2471 if ((slab = zone->uz_slab(zone, keg, flags)) == NULL) 2472 break; 2473 keg = slab->us_keg; 2474 while (slab->us_freecount && i < max) { 2475 bucket[i++] = slab_alloc_item(keg, slab); 2476 if (keg->uk_free <= keg->uk_reserve) 2477 break; 2478 } 2479 /* Don't grab more than one slab at a time. */ 2480 flags &= ~M_WAITOK; 2481 flags |= M_NOWAIT; 2482 } 2483 if (slab != NULL) 2484 KEG_UNLOCK(keg); 2485 2486 return i; 2487 } 2488 2489 static uma_bucket_t 2490 zone_alloc_bucket(uma_zone_t zone, void *udata, int flags) 2491 { 2492 uma_bucket_t bucket; 2493 int max; 2494 2495 /* Don't wait for buckets, preserve caller's NOVM setting. */ 2496 bucket = bucket_alloc(zone, udata, M_NOWAIT | (flags & M_NOVM)); 2497 if (bucket == NULL) 2498 return (NULL); 2499 2500 max = MIN(bucket->ub_entries, zone->uz_count); 2501 bucket->ub_cnt = zone->uz_import(zone->uz_arg, bucket->ub_bucket, 2502 max, flags); 2503 2504 /* 2505 * Initialize the memory if necessary. 2506 */ 2507 if (bucket->ub_cnt != 0 && zone->uz_init != NULL) { 2508 int i; 2509 2510 for (i = 0; i < bucket->ub_cnt; i++) 2511 if (zone->uz_init(bucket->ub_bucket[i], zone->uz_size, 2512 flags) != 0) 2513 break; 2514 /* 2515 * If we couldn't initialize the whole bucket, put the 2516 * rest back onto the freelist. 2517 */ 2518 if (i != bucket->ub_cnt) { 2519 zone->uz_release(zone->uz_arg, &bucket->ub_bucket[i], 2520 bucket->ub_cnt - i); 2521 #ifdef INVARIANTS 2522 bzero(&bucket->ub_bucket[i], 2523 sizeof(void *) * (bucket->ub_cnt - i)); 2524 #endif 2525 bucket->ub_cnt = i; 2526 } 2527 } 2528 2529 if (bucket->ub_cnt == 0) { 2530 bucket_free(zone, bucket, udata); 2531 atomic_add_long(&zone->uz_fails, 1); 2532 return (NULL); 2533 } 2534 2535 return (bucket); 2536 } 2537 2538 /* 2539 * Allocates a single item from a zone. 2540 * 2541 * Arguments 2542 * zone The zone to alloc for. 2543 * udata The data to be passed to the constructor. 2544 * flags M_WAITOK, M_NOWAIT, M_ZERO. 2545 * 2546 * Returns 2547 * NULL if there is no memory and M_NOWAIT is set 2548 * An item if successful 2549 */ 2550 2551 static void * 2552 zone_alloc_item(uma_zone_t zone, void *udata, int flags) 2553 { 2554 void *item; 2555 2556 item = NULL; 2557 2558 if (zone->uz_import(zone->uz_arg, &item, 1, flags) != 1) 2559 goto fail; 2560 atomic_add_long(&zone->uz_allocs, 1); 2561 2562 /* 2563 * We have to call both the zone's init (not the keg's init) 2564 * and the zone's ctor. This is because the item is going from 2565 * a keg slab directly to the user, and the user is expecting it 2566 * to be both zone-init'd as well as zone-ctor'd. 2567 */ 2568 if (zone->uz_init != NULL) { 2569 if (zone->uz_init(item, zone->uz_size, flags) != 0) { 2570 zone_free_item(zone, item, udata, SKIP_FINI); 2571 goto fail; 2572 } 2573 } 2574 if (zone->uz_ctor != NULL) { 2575 if (zone->uz_ctor(item, zone->uz_size, udata, flags) != 0) { 2576 zone_free_item(zone, item, udata, SKIP_DTOR); 2577 goto fail; 2578 } 2579 } 2580 #ifdef INVARIANTS 2581 uma_dbg_alloc(zone, NULL, item); 2582 #endif 2583 if (flags & M_ZERO) 2584 uma_zero_item(item, zone); 2585 2586 CTR3(KTR_UMA, "zone_alloc_item item %p from %s(%p)", item, 2587 zone->uz_name, zone); 2588 2589 return (item); 2590 2591 fail: 2592 CTR2(KTR_UMA, "zone_alloc_item failed from %s(%p)", 2593 zone->uz_name, zone); 2594 atomic_add_long(&zone->uz_fails, 1); 2595 return (NULL); 2596 } 2597 2598 /* See uma.h */ 2599 void 2600 uma_zfree_arg(uma_zone_t zone, void *item, void *udata) 2601 { 2602 uma_cache_t cache; 2603 uma_bucket_t bucket; 2604 int lockfail; 2605 int cpu; 2606 2607 /* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */ 2608 random_harvest_fast_uma(&zone, sizeof(zone), 1, RANDOM_UMA); 2609 2610 CTR2(KTR_UMA, "uma_zfree_arg thread %x zone %s", curthread, 2611 zone->uz_name); 2612 2613 KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(), 2614 ("uma_zfree_arg: called with spinlock or critical section held")); 2615 2616 /* uma_zfree(..., NULL) does nothing, to match free(9). */ 2617 if (item == NULL) 2618 return; 2619 #ifdef DEBUG_MEMGUARD 2620 if (is_memguard_addr(item)) { 2621 if (zone->uz_dtor != NULL) 2622 zone->uz_dtor(item, zone->uz_size, udata); 2623 if (zone->uz_fini != NULL) 2624 zone->uz_fini(item, zone->uz_size); 2625 memguard_free(item); 2626 return; 2627 } 2628 #endif 2629 #ifdef INVARIANTS 2630 if (zone->uz_flags & UMA_ZONE_MALLOC) 2631 uma_dbg_free(zone, udata, item); 2632 else 2633 uma_dbg_free(zone, NULL, item); 2634 #endif 2635 if (zone->uz_dtor != NULL) 2636 zone->uz_dtor(item, zone->uz_size, udata); 2637 2638 /* 2639 * The race here is acceptable. If we miss it we'll just have to wait 2640 * a little longer for the limits to be reset. 2641 */ 2642 if (zone->uz_flags & UMA_ZFLAG_FULL) 2643 goto zfree_item; 2644 2645 /* 2646 * If possible, free to the per-CPU cache. There are two 2647 * requirements for safe access to the per-CPU cache: (1) the thread 2648 * accessing the cache must not be preempted or yield during access, 2649 * and (2) the thread must not migrate CPUs without switching which 2650 * cache it accesses. We rely on a critical section to prevent 2651 * preemption and migration. We release the critical section in 2652 * order to acquire the zone mutex if we are unable to free to the 2653 * current cache; when we re-acquire the critical section, we must 2654 * detect and handle migration if it has occurred. 2655 */ 2656 zfree_restart: 2657 critical_enter(); 2658 cpu = curcpu; 2659 cache = &zone->uz_cpu[cpu]; 2660 2661 zfree_start: 2662 /* 2663 * Try to free into the allocbucket first to give LIFO ordering 2664 * for cache-hot datastructures. Spill over into the freebucket 2665 * if necessary. Alloc will swap them if one runs dry. 2666 */ 2667 bucket = cache->uc_allocbucket; 2668 if (bucket == NULL || bucket->ub_cnt >= bucket->ub_entries) 2669 bucket = cache->uc_freebucket; 2670 if (bucket != NULL && bucket->ub_cnt < bucket->ub_entries) { 2671 KASSERT(bucket->ub_bucket[bucket->ub_cnt] == NULL, 2672 ("uma_zfree: Freeing to non free bucket index.")); 2673 bucket->ub_bucket[bucket->ub_cnt] = item; 2674 bucket->ub_cnt++; 2675 cache->uc_frees++; 2676 critical_exit(); 2677 return; 2678 } 2679 2680 /* 2681 * We must go back the zone, which requires acquiring the zone lock, 2682 * which in turn means we must release and re-acquire the critical 2683 * section. Since the critical section is released, we may be 2684 * preempted or migrate. As such, make sure not to maintain any 2685 * thread-local state specific to the cache from prior to releasing 2686 * the critical section. 2687 */ 2688 critical_exit(); 2689 if (zone->uz_count == 0 || bucketdisable) 2690 goto zfree_item; 2691 2692 lockfail = 0; 2693 if (ZONE_TRYLOCK(zone) == 0) { 2694 /* Record contention to size the buckets. */ 2695 ZONE_LOCK(zone); 2696 lockfail = 1; 2697 } 2698 critical_enter(); 2699 cpu = curcpu; 2700 cache = &zone->uz_cpu[cpu]; 2701 2702 /* 2703 * Since we have locked the zone we may as well send back our stats. 2704 */ 2705 atomic_add_long(&zone->uz_allocs, cache->uc_allocs); 2706 atomic_add_long(&zone->uz_frees, cache->uc_frees); 2707 cache->uc_allocs = 0; 2708 cache->uc_frees = 0; 2709 2710 bucket = cache->uc_freebucket; 2711 if (bucket != NULL && bucket->ub_cnt < bucket->ub_entries) { 2712 ZONE_UNLOCK(zone); 2713 goto zfree_start; 2714 } 2715 cache->uc_freebucket = NULL; 2716 /* We are no longer associated with this CPU. */ 2717 critical_exit(); 2718 2719 /* Can we throw this on the zone full list? */ 2720 if (bucket != NULL) { 2721 CTR3(KTR_UMA, 2722 "uma_zfree: zone %s(%p) putting bucket %p on free list", 2723 zone->uz_name, zone, bucket); 2724 /* ub_cnt is pointing to the last free item */ 2725 KASSERT(bucket->ub_cnt != 0, 2726 ("uma_zfree: Attempting to insert an empty bucket onto the full list.\n")); 2727 LIST_INSERT_HEAD(&zone->uz_buckets, bucket, ub_link); 2728 } 2729 2730 /* 2731 * We bump the uz count when the cache size is insufficient to 2732 * handle the working set. 2733 */ 2734 if (lockfail && zone->uz_count < BUCKET_MAX) 2735 zone->uz_count++; 2736 ZONE_UNLOCK(zone); 2737 2738 bucket = bucket_alloc(zone, udata, M_NOWAIT); 2739 CTR3(KTR_UMA, "uma_zfree: zone %s(%p) allocated bucket %p", 2740 zone->uz_name, zone, bucket); 2741 if (bucket) { 2742 critical_enter(); 2743 cpu = curcpu; 2744 cache = &zone->uz_cpu[cpu]; 2745 if (cache->uc_freebucket == NULL) { 2746 cache->uc_freebucket = bucket; 2747 goto zfree_start; 2748 } 2749 /* 2750 * We lost the race, start over. We have to drop our 2751 * critical section to free the bucket. 2752 */ 2753 critical_exit(); 2754 bucket_free(zone, bucket, udata); 2755 goto zfree_restart; 2756 } 2757 2758 /* 2759 * If nothing else caught this, we'll just do an internal free. 2760 */ 2761 zfree_item: 2762 zone_free_item(zone, item, udata, SKIP_DTOR); 2763 2764 return; 2765 } 2766 2767 static void 2768 slab_free_item(uma_keg_t keg, uma_slab_t slab, void *item) 2769 { 2770 uint8_t freei; 2771 2772 mtx_assert(&keg->uk_lock, MA_OWNED); 2773 MPASS(keg == slab->us_keg); 2774 2775 /* Do we need to remove from any lists? */ 2776 if (slab->us_freecount+1 == keg->uk_ipers) { 2777 LIST_REMOVE(slab, us_link); 2778 LIST_INSERT_HEAD(&keg->uk_free_slab, slab, us_link); 2779 } else if (slab->us_freecount == 0) { 2780 LIST_REMOVE(slab, us_link); 2781 LIST_INSERT_HEAD(&keg->uk_part_slab, slab, us_link); 2782 } 2783 2784 /* Slab management. */ 2785 freei = ((uintptr_t)item - (uintptr_t)slab->us_data) / keg->uk_rsize; 2786 BIT_SET(SLAB_SETSIZE, freei, &slab->us_free); 2787 slab->us_freecount++; 2788 2789 /* Keg statistics. */ 2790 keg->uk_free++; 2791 } 2792 2793 static void 2794 zone_release(uma_zone_t zone, void **bucket, int cnt) 2795 { 2796 void *item; 2797 uma_slab_t slab; 2798 uma_keg_t keg; 2799 uint8_t *mem; 2800 int clearfull; 2801 int i; 2802 2803 clearfull = 0; 2804 keg = zone_first_keg(zone); 2805 KEG_LOCK(keg); 2806 for (i = 0; i < cnt; i++) { 2807 item = bucket[i]; 2808 if (!(zone->uz_flags & UMA_ZONE_VTOSLAB)) { 2809 mem = (uint8_t *)((uintptr_t)item & (~UMA_SLAB_MASK)); 2810 if (zone->uz_flags & UMA_ZONE_HASH) { 2811 slab = hash_sfind(&keg->uk_hash, mem); 2812 } else { 2813 mem += keg->uk_pgoff; 2814 slab = (uma_slab_t)mem; 2815 } 2816 } else { 2817 slab = vtoslab((vm_offset_t)item); 2818 if (slab->us_keg != keg) { 2819 KEG_UNLOCK(keg); 2820 keg = slab->us_keg; 2821 KEG_LOCK(keg); 2822 } 2823 } 2824 slab_free_item(keg, slab, item); 2825 if (keg->uk_flags & UMA_ZFLAG_FULL) { 2826 if (keg->uk_pages < keg->uk_maxpages) { 2827 keg->uk_flags &= ~UMA_ZFLAG_FULL; 2828 clearfull = 1; 2829 } 2830 2831 /* 2832 * We can handle one more allocation. Since we're 2833 * clearing ZFLAG_FULL, wake up all procs blocked 2834 * on pages. This should be uncommon, so keeping this 2835 * simple for now (rather than adding count of blocked 2836 * threads etc). 2837 */ 2838 wakeup(keg); 2839 } 2840 } 2841 KEG_UNLOCK(keg); 2842 if (clearfull) { 2843 ZONE_LOCK(zone); 2844 zone->uz_flags &= ~UMA_ZFLAG_FULL; 2845 wakeup(zone); 2846 ZONE_UNLOCK(zone); 2847 } 2848 2849 } 2850 2851 /* 2852 * Frees a single item to any zone. 2853 * 2854 * Arguments: 2855 * zone The zone to free to 2856 * item The item we're freeing 2857 * udata User supplied data for the dtor 2858 * skip Skip dtors and finis 2859 */ 2860 static void 2861 zone_free_item(uma_zone_t zone, void *item, void *udata, enum zfreeskip skip) 2862 { 2863 2864 #ifdef INVARIANTS 2865 if (skip == SKIP_NONE) { 2866 if (zone->uz_flags & UMA_ZONE_MALLOC) 2867 uma_dbg_free(zone, udata, item); 2868 else 2869 uma_dbg_free(zone, NULL, item); 2870 } 2871 #endif 2872 if (skip < SKIP_DTOR && zone->uz_dtor) 2873 zone->uz_dtor(item, zone->uz_size, udata); 2874 2875 if (skip < SKIP_FINI && zone->uz_fini) 2876 zone->uz_fini(item, zone->uz_size); 2877 2878 atomic_add_long(&zone->uz_frees, 1); 2879 zone->uz_release(zone->uz_arg, &item, 1); 2880 } 2881 2882 /* See uma.h */ 2883 int 2884 uma_zone_set_max(uma_zone_t zone, int nitems) 2885 { 2886 uma_keg_t keg; 2887 2888 keg = zone_first_keg(zone); 2889 if (keg == NULL) 2890 return (0); 2891 KEG_LOCK(keg); 2892 keg->uk_maxpages = (nitems / keg->uk_ipers) * keg->uk_ppera; 2893 if (keg->uk_maxpages * keg->uk_ipers < nitems) 2894 keg->uk_maxpages += keg->uk_ppera; 2895 nitems = (keg->uk_maxpages / keg->uk_ppera) * keg->uk_ipers; 2896 KEG_UNLOCK(keg); 2897 2898 return (nitems); 2899 } 2900 2901 /* See uma.h */ 2902 int 2903 uma_zone_get_max(uma_zone_t zone) 2904 { 2905 int nitems; 2906 uma_keg_t keg; 2907 2908 keg = zone_first_keg(zone); 2909 if (keg == NULL) 2910 return (0); 2911 KEG_LOCK(keg); 2912 nitems = (keg->uk_maxpages / keg->uk_ppera) * keg->uk_ipers; 2913 KEG_UNLOCK(keg); 2914 2915 return (nitems); 2916 } 2917 2918 /* See uma.h */ 2919 void 2920 uma_zone_set_warning(uma_zone_t zone, const char *warning) 2921 { 2922 2923 ZONE_LOCK(zone); 2924 zone->uz_warning = warning; 2925 ZONE_UNLOCK(zone); 2926 } 2927 2928 /* See uma.h */ 2929 void 2930 uma_zone_set_maxaction(uma_zone_t zone, uma_maxaction_t maxaction) 2931 { 2932 2933 ZONE_LOCK(zone); 2934 TASK_INIT(&zone->uz_maxaction, 0, (task_fn_t *)maxaction, zone); 2935 ZONE_UNLOCK(zone); 2936 } 2937 2938 /* See uma.h */ 2939 int 2940 uma_zone_get_cur(uma_zone_t zone) 2941 { 2942 int64_t nitems; 2943 u_int i; 2944 2945 ZONE_LOCK(zone); 2946 nitems = zone->uz_allocs - zone->uz_frees; 2947 CPU_FOREACH(i) { 2948 /* 2949 * See the comment in sysctl_vm_zone_stats() regarding the 2950 * safety of accessing the per-cpu caches. With the zone lock 2951 * held, it is safe, but can potentially result in stale data. 2952 */ 2953 nitems += zone->uz_cpu[i].uc_allocs - 2954 zone->uz_cpu[i].uc_frees; 2955 } 2956 ZONE_UNLOCK(zone); 2957 2958 return (nitems < 0 ? 0 : nitems); 2959 } 2960 2961 /* See uma.h */ 2962 void 2963 uma_zone_set_init(uma_zone_t zone, uma_init uminit) 2964 { 2965 uma_keg_t keg; 2966 2967 keg = zone_first_keg(zone); 2968 KASSERT(keg != NULL, ("uma_zone_set_init: Invalid zone type")); 2969 KEG_LOCK(keg); 2970 KASSERT(keg->uk_pages == 0, 2971 ("uma_zone_set_init on non-empty keg")); 2972 keg->uk_init = uminit; 2973 KEG_UNLOCK(keg); 2974 } 2975 2976 /* See uma.h */ 2977 void 2978 uma_zone_set_fini(uma_zone_t zone, uma_fini fini) 2979 { 2980 uma_keg_t keg; 2981 2982 keg = zone_first_keg(zone); 2983 KASSERT(keg != NULL, ("uma_zone_set_fini: Invalid zone type")); 2984 KEG_LOCK(keg); 2985 KASSERT(keg->uk_pages == 0, 2986 ("uma_zone_set_fini on non-empty keg")); 2987 keg->uk_fini = fini; 2988 KEG_UNLOCK(keg); 2989 } 2990 2991 /* See uma.h */ 2992 void 2993 uma_zone_set_zinit(uma_zone_t zone, uma_init zinit) 2994 { 2995 2996 ZONE_LOCK(zone); 2997 KASSERT(zone_first_keg(zone)->uk_pages == 0, 2998 ("uma_zone_set_zinit on non-empty keg")); 2999 zone->uz_init = zinit; 3000 ZONE_UNLOCK(zone); 3001 } 3002 3003 /* See uma.h */ 3004 void 3005 uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini) 3006 { 3007 3008 ZONE_LOCK(zone); 3009 KASSERT(zone_first_keg(zone)->uk_pages == 0, 3010 ("uma_zone_set_zfini on non-empty keg")); 3011 zone->uz_fini = zfini; 3012 ZONE_UNLOCK(zone); 3013 } 3014 3015 /* See uma.h */ 3016 /* XXX uk_freef is not actually used with the zone locked */ 3017 void 3018 uma_zone_set_freef(uma_zone_t zone, uma_free freef) 3019 { 3020 uma_keg_t keg; 3021 3022 keg = zone_first_keg(zone); 3023 KASSERT(keg != NULL, ("uma_zone_set_freef: Invalid zone type")); 3024 KEG_LOCK(keg); 3025 keg->uk_freef = freef; 3026 KEG_UNLOCK(keg); 3027 } 3028 3029 /* See uma.h */ 3030 /* XXX uk_allocf is not actually used with the zone locked */ 3031 void 3032 uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf) 3033 { 3034 uma_keg_t keg; 3035 3036 keg = zone_first_keg(zone); 3037 KEG_LOCK(keg); 3038 keg->uk_allocf = allocf; 3039 KEG_UNLOCK(keg); 3040 } 3041 3042 /* See uma.h */ 3043 void 3044 uma_zone_reserve(uma_zone_t zone, int items) 3045 { 3046 uma_keg_t keg; 3047 3048 keg = zone_first_keg(zone); 3049 if (keg == NULL) 3050 return; 3051 KEG_LOCK(keg); 3052 keg->uk_reserve = items; 3053 KEG_UNLOCK(keg); 3054 3055 return; 3056 } 3057 3058 /* See uma.h */ 3059 int 3060 uma_zone_reserve_kva(uma_zone_t zone, int count) 3061 { 3062 uma_keg_t keg; 3063 vm_offset_t kva; 3064 u_int pages; 3065 3066 keg = zone_first_keg(zone); 3067 if (keg == NULL) 3068 return (0); 3069 pages = count / keg->uk_ipers; 3070 3071 if (pages * keg->uk_ipers < count) 3072 pages++; 3073 pages *= keg->uk_ppera; 3074 3075 #ifdef UMA_MD_SMALL_ALLOC 3076 if (keg->uk_ppera > 1) { 3077 #else 3078 if (1) { 3079 #endif 3080 kva = kva_alloc((vm_size_t)pages * PAGE_SIZE); 3081 if (kva == 0) 3082 return (0); 3083 } else 3084 kva = 0; 3085 KEG_LOCK(keg); 3086 keg->uk_kva = kva; 3087 keg->uk_offset = 0; 3088 keg->uk_maxpages = pages; 3089 #ifdef UMA_MD_SMALL_ALLOC 3090 keg->uk_allocf = (keg->uk_ppera > 1) ? noobj_alloc : uma_small_alloc; 3091 #else 3092 keg->uk_allocf = noobj_alloc; 3093 #endif 3094 keg->uk_flags |= UMA_ZONE_NOFREE; 3095 KEG_UNLOCK(keg); 3096 3097 return (1); 3098 } 3099 3100 /* See uma.h */ 3101 void 3102 uma_prealloc(uma_zone_t zone, int items) 3103 { 3104 int slabs; 3105 uma_slab_t slab; 3106 uma_keg_t keg; 3107 3108 keg = zone_first_keg(zone); 3109 if (keg == NULL) 3110 return; 3111 KEG_LOCK(keg); 3112 slabs = items / keg->uk_ipers; 3113 if (slabs * keg->uk_ipers < items) 3114 slabs++; 3115 while (slabs > 0) { 3116 slab = keg_alloc_slab(keg, zone, M_WAITOK); 3117 if (slab == NULL) 3118 break; 3119 MPASS(slab->us_keg == keg); 3120 LIST_INSERT_HEAD(&keg->uk_free_slab, slab, us_link); 3121 slabs--; 3122 } 3123 KEG_UNLOCK(keg); 3124 } 3125 3126 /* See uma.h */ 3127 static void 3128 uma_reclaim_locked(bool kmem_danger) 3129 { 3130 3131 CTR0(KTR_UMA, "UMA: vm asked us to release pages!"); 3132 sx_assert(&uma_drain_lock, SA_XLOCKED); 3133 bucket_enable(); 3134 zone_foreach(zone_drain); 3135 if (vm_page_count_min() || kmem_danger) { 3136 cache_drain_safe(NULL); 3137 zone_foreach(zone_drain); 3138 } 3139 /* 3140 * Some slabs may have been freed but this zone will be visited early 3141 * we visit again so that we can free pages that are empty once other 3142 * zones are drained. We have to do the same for buckets. 3143 */ 3144 zone_drain(slabzone); 3145 bucket_zone_drain(); 3146 } 3147 3148 void 3149 uma_reclaim(void) 3150 { 3151 3152 sx_xlock(&uma_drain_lock); 3153 uma_reclaim_locked(false); 3154 sx_xunlock(&uma_drain_lock); 3155 } 3156 3157 static volatile int uma_reclaim_needed; 3158 3159 void 3160 uma_reclaim_wakeup(void) 3161 { 3162 3163 if (atomic_fetchadd_int(&uma_reclaim_needed, 1) == 0) 3164 wakeup(uma_reclaim); 3165 } 3166 3167 void 3168 uma_reclaim_worker(void *arg __unused) 3169 { 3170 3171 for (;;) { 3172 sx_xlock(&uma_drain_lock); 3173 while (atomic_load_int(&uma_reclaim_needed) == 0) 3174 sx_sleep(uma_reclaim, &uma_drain_lock, PVM, "umarcl", 3175 hz); 3176 sx_xunlock(&uma_drain_lock); 3177 EVENTHANDLER_INVOKE(vm_lowmem, VM_LOW_KMEM); 3178 sx_xlock(&uma_drain_lock); 3179 uma_reclaim_locked(true); 3180 atomic_store_int(&uma_reclaim_needed, 0); 3181 sx_xunlock(&uma_drain_lock); 3182 /* Don't fire more than once per-second. */ 3183 pause("umarclslp", hz); 3184 } 3185 } 3186 3187 /* See uma.h */ 3188 int 3189 uma_zone_exhausted(uma_zone_t zone) 3190 { 3191 int full; 3192 3193 ZONE_LOCK(zone); 3194 full = (zone->uz_flags & UMA_ZFLAG_FULL); 3195 ZONE_UNLOCK(zone); 3196 return (full); 3197 } 3198 3199 int 3200 uma_zone_exhausted_nolock(uma_zone_t zone) 3201 { 3202 return (zone->uz_flags & UMA_ZFLAG_FULL); 3203 } 3204 3205 void * 3206 uma_large_malloc(vm_size_t size, int wait) 3207 { 3208 void *mem; 3209 uma_slab_t slab; 3210 uint8_t flags; 3211 3212 slab = zone_alloc_item(slabzone, NULL, wait); 3213 if (slab == NULL) 3214 return (NULL); 3215 mem = page_alloc(NULL, size, &flags, wait); 3216 if (mem) { 3217 vsetslab((vm_offset_t)mem, slab); 3218 slab->us_data = mem; 3219 slab->us_flags = flags | UMA_SLAB_MALLOC; 3220 slab->us_size = size; 3221 uma_total_inc(size); 3222 } else { 3223 zone_free_item(slabzone, slab, NULL, SKIP_NONE); 3224 } 3225 3226 return (mem); 3227 } 3228 3229 void 3230 uma_large_free(uma_slab_t slab) 3231 { 3232 3233 page_free(slab->us_data, slab->us_size, slab->us_flags); 3234 uma_total_dec(slab->us_size); 3235 zone_free_item(slabzone, slab, NULL, SKIP_NONE); 3236 } 3237 3238 static void 3239 uma_zero_item(void *item, uma_zone_t zone) 3240 { 3241 int i; 3242 3243 if (zone->uz_flags & UMA_ZONE_PCPU) { 3244 CPU_FOREACH(i) 3245 bzero(zpcpu_get_cpu(item, i), zone->uz_size); 3246 } else 3247 bzero(item, zone->uz_size); 3248 } 3249 3250 unsigned long 3251 uma_limit(void) 3252 { 3253 3254 return (uma_kmem_limit); 3255 } 3256 3257 void 3258 uma_set_limit(unsigned long limit) 3259 { 3260 3261 uma_kmem_limit = limit; 3262 } 3263 3264 unsigned long 3265 uma_size(void) 3266 { 3267 3268 return uma_kmem_total; 3269 } 3270 3271 void 3272 uma_print_stats(void) 3273 { 3274 zone_foreach(uma_print_zone); 3275 } 3276 3277 static void 3278 slab_print(uma_slab_t slab) 3279 { 3280 printf("slab: keg %p, data %p, freecount %d\n", 3281 slab->us_keg, slab->us_data, slab->us_freecount); 3282 } 3283 3284 static void 3285 cache_print(uma_cache_t cache) 3286 { 3287 printf("alloc: %p(%d), free: %p(%d)\n", 3288 cache->uc_allocbucket, 3289 cache->uc_allocbucket?cache->uc_allocbucket->ub_cnt:0, 3290 cache->uc_freebucket, 3291 cache->uc_freebucket?cache->uc_freebucket->ub_cnt:0); 3292 } 3293 3294 static void 3295 uma_print_keg(uma_keg_t keg) 3296 { 3297 uma_slab_t slab; 3298 3299 printf("keg: %s(%p) size %d(%d) flags %#x ipers %d ppera %d " 3300 "out %d free %d limit %d\n", 3301 keg->uk_name, keg, keg->uk_size, keg->uk_rsize, keg->uk_flags, 3302 keg->uk_ipers, keg->uk_ppera, 3303 (keg->uk_pages / keg->uk_ppera) * keg->uk_ipers - keg->uk_free, 3304 keg->uk_free, (keg->uk_maxpages / keg->uk_ppera) * keg->uk_ipers); 3305 printf("Part slabs:\n"); 3306 LIST_FOREACH(slab, &keg->uk_part_slab, us_link) 3307 slab_print(slab); 3308 printf("Free slabs:\n"); 3309 LIST_FOREACH(slab, &keg->uk_free_slab, us_link) 3310 slab_print(slab); 3311 printf("Full slabs:\n"); 3312 LIST_FOREACH(slab, &keg->uk_full_slab, us_link) 3313 slab_print(slab); 3314 } 3315 3316 void 3317 uma_print_zone(uma_zone_t zone) 3318 { 3319 uma_cache_t cache; 3320 uma_klink_t kl; 3321 int i; 3322 3323 printf("zone: %s(%p) size %d flags %#x\n", 3324 zone->uz_name, zone, zone->uz_size, zone->uz_flags); 3325 LIST_FOREACH(kl, &zone->uz_kegs, kl_link) 3326 uma_print_keg(kl->kl_keg); 3327 CPU_FOREACH(i) { 3328 cache = &zone->uz_cpu[i]; 3329 printf("CPU %d Cache:\n", i); 3330 cache_print(cache); 3331 } 3332 } 3333 3334 #ifdef DDB 3335 /* 3336 * Generate statistics across both the zone and its per-cpu cache's. Return 3337 * desired statistics if the pointer is non-NULL for that statistic. 3338 * 3339 * Note: does not update the zone statistics, as it can't safely clear the 3340 * per-CPU cache statistic. 3341 * 3342 * XXXRW: Following the uc_allocbucket and uc_freebucket pointers here isn't 3343 * safe from off-CPU; we should modify the caches to track this information 3344 * directly so that we don't have to. 3345 */ 3346 static void 3347 uma_zone_sumstat(uma_zone_t z, int *cachefreep, uint64_t *allocsp, 3348 uint64_t *freesp, uint64_t *sleepsp) 3349 { 3350 uma_cache_t cache; 3351 uint64_t allocs, frees, sleeps; 3352 int cachefree, cpu; 3353 3354 allocs = frees = sleeps = 0; 3355 cachefree = 0; 3356 CPU_FOREACH(cpu) { 3357 cache = &z->uz_cpu[cpu]; 3358 if (cache->uc_allocbucket != NULL) 3359 cachefree += cache->uc_allocbucket->ub_cnt; 3360 if (cache->uc_freebucket != NULL) 3361 cachefree += cache->uc_freebucket->ub_cnt; 3362 allocs += cache->uc_allocs; 3363 frees += cache->uc_frees; 3364 } 3365 allocs += z->uz_allocs; 3366 frees += z->uz_frees; 3367 sleeps += z->uz_sleeps; 3368 if (cachefreep != NULL) 3369 *cachefreep = cachefree; 3370 if (allocsp != NULL) 3371 *allocsp = allocs; 3372 if (freesp != NULL) 3373 *freesp = frees; 3374 if (sleepsp != NULL) 3375 *sleepsp = sleeps; 3376 } 3377 #endif /* DDB */ 3378 3379 static int 3380 sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS) 3381 { 3382 uma_keg_t kz; 3383 uma_zone_t z; 3384 int count; 3385 3386 count = 0; 3387 rw_rlock(&uma_rwlock); 3388 LIST_FOREACH(kz, &uma_kegs, uk_link) { 3389 LIST_FOREACH(z, &kz->uk_zones, uz_link) 3390 count++; 3391 } 3392 rw_runlock(&uma_rwlock); 3393 return (sysctl_handle_int(oidp, &count, 0, req)); 3394 } 3395 3396 static int 3397 sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS) 3398 { 3399 struct uma_stream_header ush; 3400 struct uma_type_header uth; 3401 struct uma_percpu_stat ups; 3402 uma_bucket_t bucket; 3403 struct sbuf sbuf; 3404 uma_cache_t cache; 3405 uma_klink_t kl; 3406 uma_keg_t kz; 3407 uma_zone_t z; 3408 uma_keg_t k; 3409 int count, error, i; 3410 3411 error = sysctl_wire_old_buffer(req, 0); 3412 if (error != 0) 3413 return (error); 3414 sbuf_new_for_sysctl(&sbuf, NULL, 128, req); 3415 sbuf_clear_flags(&sbuf, SBUF_INCLUDENUL); 3416 3417 count = 0; 3418 rw_rlock(&uma_rwlock); 3419 LIST_FOREACH(kz, &uma_kegs, uk_link) { 3420 LIST_FOREACH(z, &kz->uk_zones, uz_link) 3421 count++; 3422 } 3423 3424 /* 3425 * Insert stream header. 3426 */ 3427 bzero(&ush, sizeof(ush)); 3428 ush.ush_version = UMA_STREAM_VERSION; 3429 ush.ush_maxcpus = (mp_maxid + 1); 3430 ush.ush_count = count; 3431 (void)sbuf_bcat(&sbuf, &ush, sizeof(ush)); 3432 3433 LIST_FOREACH(kz, &uma_kegs, uk_link) { 3434 LIST_FOREACH(z, &kz->uk_zones, uz_link) { 3435 bzero(&uth, sizeof(uth)); 3436 ZONE_LOCK(z); 3437 strlcpy(uth.uth_name, z->uz_name, UTH_MAX_NAME); 3438 uth.uth_align = kz->uk_align; 3439 uth.uth_size = kz->uk_size; 3440 uth.uth_rsize = kz->uk_rsize; 3441 LIST_FOREACH(kl, &z->uz_kegs, kl_link) { 3442 k = kl->kl_keg; 3443 uth.uth_maxpages += k->uk_maxpages; 3444 uth.uth_pages += k->uk_pages; 3445 uth.uth_keg_free += k->uk_free; 3446 uth.uth_limit = (k->uk_maxpages / k->uk_ppera) 3447 * k->uk_ipers; 3448 } 3449 3450 /* 3451 * A zone is secondary is it is not the first entry 3452 * on the keg's zone list. 3453 */ 3454 if ((z->uz_flags & UMA_ZONE_SECONDARY) && 3455 (LIST_FIRST(&kz->uk_zones) != z)) 3456 uth.uth_zone_flags = UTH_ZONE_SECONDARY; 3457 3458 LIST_FOREACH(bucket, &z->uz_buckets, ub_link) 3459 uth.uth_zone_free += bucket->ub_cnt; 3460 uth.uth_allocs = z->uz_allocs; 3461 uth.uth_frees = z->uz_frees; 3462 uth.uth_fails = z->uz_fails; 3463 uth.uth_sleeps = z->uz_sleeps; 3464 (void)sbuf_bcat(&sbuf, &uth, sizeof(uth)); 3465 /* 3466 * While it is not normally safe to access the cache 3467 * bucket pointers while not on the CPU that owns the 3468 * cache, we only allow the pointers to be exchanged 3469 * without the zone lock held, not invalidated, so 3470 * accept the possible race associated with bucket 3471 * exchange during monitoring. 3472 */ 3473 for (i = 0; i < (mp_maxid + 1); i++) { 3474 bzero(&ups, sizeof(ups)); 3475 if (kz->uk_flags & UMA_ZFLAG_INTERNAL) 3476 goto skip; 3477 if (CPU_ABSENT(i)) 3478 goto skip; 3479 cache = &z->uz_cpu[i]; 3480 if (cache->uc_allocbucket != NULL) 3481 ups.ups_cache_free += 3482 cache->uc_allocbucket->ub_cnt; 3483 if (cache->uc_freebucket != NULL) 3484 ups.ups_cache_free += 3485 cache->uc_freebucket->ub_cnt; 3486 ups.ups_allocs = cache->uc_allocs; 3487 ups.ups_frees = cache->uc_frees; 3488 skip: 3489 (void)sbuf_bcat(&sbuf, &ups, sizeof(ups)); 3490 } 3491 ZONE_UNLOCK(z); 3492 } 3493 } 3494 rw_runlock(&uma_rwlock); 3495 error = sbuf_finish(&sbuf); 3496 sbuf_delete(&sbuf); 3497 return (error); 3498 } 3499 3500 int 3501 sysctl_handle_uma_zone_max(SYSCTL_HANDLER_ARGS) 3502 { 3503 uma_zone_t zone = *(uma_zone_t *)arg1; 3504 int error, max; 3505 3506 max = uma_zone_get_max(zone); 3507 error = sysctl_handle_int(oidp, &max, 0, req); 3508 if (error || !req->newptr) 3509 return (error); 3510 3511 uma_zone_set_max(zone, max); 3512 3513 return (0); 3514 } 3515 3516 int 3517 sysctl_handle_uma_zone_cur(SYSCTL_HANDLER_ARGS) 3518 { 3519 uma_zone_t zone = *(uma_zone_t *)arg1; 3520 int cur; 3521 3522 cur = uma_zone_get_cur(zone); 3523 return (sysctl_handle_int(oidp, &cur, 0, req)); 3524 } 3525 3526 #ifdef INVARIANTS 3527 static uma_slab_t 3528 uma_dbg_getslab(uma_zone_t zone, void *item) 3529 { 3530 uma_slab_t slab; 3531 uma_keg_t keg; 3532 uint8_t *mem; 3533 3534 mem = (uint8_t *)((uintptr_t)item & (~UMA_SLAB_MASK)); 3535 if (zone->uz_flags & UMA_ZONE_VTOSLAB) { 3536 slab = vtoslab((vm_offset_t)mem); 3537 } else { 3538 /* 3539 * It is safe to return the slab here even though the 3540 * zone is unlocked because the item's allocation state 3541 * essentially holds a reference. 3542 */ 3543 ZONE_LOCK(zone); 3544 keg = LIST_FIRST(&zone->uz_kegs)->kl_keg; 3545 if (keg->uk_flags & UMA_ZONE_HASH) 3546 slab = hash_sfind(&keg->uk_hash, mem); 3547 else 3548 slab = (uma_slab_t)(mem + keg->uk_pgoff); 3549 ZONE_UNLOCK(zone); 3550 } 3551 3552 return (slab); 3553 } 3554 3555 /* 3556 * Set up the slab's freei data such that uma_dbg_free can function. 3557 * 3558 */ 3559 static void 3560 uma_dbg_alloc(uma_zone_t zone, uma_slab_t slab, void *item) 3561 { 3562 uma_keg_t keg; 3563 int freei; 3564 3565 if (zone_first_keg(zone) == NULL) 3566 return; 3567 if (slab == NULL) { 3568 slab = uma_dbg_getslab(zone, item); 3569 if (slab == NULL) 3570 panic("uma: item %p did not belong to zone %s\n", 3571 item, zone->uz_name); 3572 } 3573 keg = slab->us_keg; 3574 freei = ((uintptr_t)item - (uintptr_t)slab->us_data) / keg->uk_rsize; 3575 3576 if (BIT_ISSET(SLAB_SETSIZE, freei, &slab->us_debugfree)) 3577 panic("Duplicate alloc of %p from zone %p(%s) slab %p(%d)\n", 3578 item, zone, zone->uz_name, slab, freei); 3579 BIT_SET_ATOMIC(SLAB_SETSIZE, freei, &slab->us_debugfree); 3580 3581 return; 3582 } 3583 3584 /* 3585 * Verifies freed addresses. Checks for alignment, valid slab membership 3586 * and duplicate frees. 3587 * 3588 */ 3589 static void 3590 uma_dbg_free(uma_zone_t zone, uma_slab_t slab, void *item) 3591 { 3592 uma_keg_t keg; 3593 int freei; 3594 3595 if (zone_first_keg(zone) == NULL) 3596 return; 3597 if (slab == NULL) { 3598 slab = uma_dbg_getslab(zone, item); 3599 if (slab == NULL) 3600 panic("uma: Freed item %p did not belong to zone %s\n", 3601 item, zone->uz_name); 3602 } 3603 keg = slab->us_keg; 3604 freei = ((uintptr_t)item - (uintptr_t)slab->us_data) / keg->uk_rsize; 3605 3606 if (freei >= keg->uk_ipers) 3607 panic("Invalid free of %p from zone %p(%s) slab %p(%d)\n", 3608 item, zone, zone->uz_name, slab, freei); 3609 3610 if (((freei * keg->uk_rsize) + slab->us_data) != item) 3611 panic("Unaligned free of %p from zone %p(%s) slab %p(%d)\n", 3612 item, zone, zone->uz_name, slab, freei); 3613 3614 if (!BIT_ISSET(SLAB_SETSIZE, freei, &slab->us_debugfree)) 3615 panic("Duplicate free of %p from zone %p(%s) slab %p(%d)\n", 3616 item, zone, zone->uz_name, slab, freei); 3617 3618 BIT_CLR_ATOMIC(SLAB_SETSIZE, freei, &slab->us_debugfree); 3619 } 3620 #endif /* INVARIANTS */ 3621 3622 #ifdef DDB 3623 DB_SHOW_COMMAND(uma, db_show_uma) 3624 { 3625 uint64_t allocs, frees, sleeps; 3626 uma_bucket_t bucket; 3627 uma_keg_t kz; 3628 uma_zone_t z; 3629 int cachefree; 3630 3631 db_printf("%18s %8s %8s %8s %12s %8s %8s\n", "Zone", "Size", "Used", 3632 "Free", "Requests", "Sleeps", "Bucket"); 3633 LIST_FOREACH(kz, &uma_kegs, uk_link) { 3634 LIST_FOREACH(z, &kz->uk_zones, uz_link) { 3635 if (kz->uk_flags & UMA_ZFLAG_INTERNAL) { 3636 allocs = z->uz_allocs; 3637 frees = z->uz_frees; 3638 sleeps = z->uz_sleeps; 3639 cachefree = 0; 3640 } else 3641 uma_zone_sumstat(z, &cachefree, &allocs, 3642 &frees, &sleeps); 3643 if (!((z->uz_flags & UMA_ZONE_SECONDARY) && 3644 (LIST_FIRST(&kz->uk_zones) != z))) 3645 cachefree += kz->uk_free; 3646 LIST_FOREACH(bucket, &z->uz_buckets, ub_link) 3647 cachefree += bucket->ub_cnt; 3648 db_printf("%18s %8ju %8jd %8d %12ju %8ju %8u\n", 3649 z->uz_name, (uintmax_t)kz->uk_size, 3650 (intmax_t)(allocs - frees), cachefree, 3651 (uintmax_t)allocs, sleeps, z->uz_count); 3652 if (db_pager_quit) 3653 return; 3654 } 3655 } 3656 } 3657 3658 DB_SHOW_COMMAND(umacache, db_show_umacache) 3659 { 3660 uint64_t allocs, frees; 3661 uma_bucket_t bucket; 3662 uma_zone_t z; 3663 int cachefree; 3664 3665 db_printf("%18s %8s %8s %8s %12s %8s\n", "Zone", "Size", "Used", "Free", 3666 "Requests", "Bucket"); 3667 LIST_FOREACH(z, &uma_cachezones, uz_link) { 3668 uma_zone_sumstat(z, &cachefree, &allocs, &frees, NULL); 3669 LIST_FOREACH(bucket, &z->uz_buckets, ub_link) 3670 cachefree += bucket->ub_cnt; 3671 db_printf("%18s %8ju %8jd %8d %12ju %8u\n", 3672 z->uz_name, (uintmax_t)z->uz_size, 3673 (intmax_t)(allocs - frees), cachefree, 3674 (uintmax_t)allocs, z->uz_count); 3675 if (db_pager_quit) 3676 return; 3677 } 3678 } 3679 #endif /* DDB */ 3680