1 /*- 2 * Copyright (c) 2002, 2003, 2004, 2005 Jeffrey Roberson <jeff@FreeBSD.org> 3 * Copyright (c) 2004, 2005 Bosko Milekic <bmilekic@FreeBSD.org> 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice unmodified, this list of conditions, and the following 11 * disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 * 27 * $FreeBSD$ 28 * 29 */ 30 31 /* 32 * uma.h - External definitions for the Universal Memory Allocator 33 * 34 */ 35 36 #ifndef VM_UMA_H 37 #define VM_UMA_H 38 39 #include <sys/param.h> /* For NULL */ 40 #include <sys/malloc.h> /* For M_* */ 41 42 /* User visable parameters */ 43 #define UMA_SMALLEST_UNIT (PAGE_SIZE / 256) /* Smallest item allocated */ 44 45 /* Types and type defs */ 46 47 struct uma_zone; 48 /* Opaque type used as a handle to the zone */ 49 typedef struct uma_zone * uma_zone_t; 50 51 /* 52 * Item constructor 53 * 54 * Arguments: 55 * item A pointer to the memory which has been allocated. 56 * arg The arg field passed to uma_zalloc_arg 57 * size The size of the allocated item 58 * flags See zalloc flags 59 * 60 * Returns: 61 * 0 on success 62 * errno on failure 63 * 64 * Discussion: 65 * The constructor is called just before the memory is returned 66 * to the user. It may block if necessary. 67 */ 68 typedef int (*uma_ctor)(void *mem, int size, void *arg, int flags); 69 70 /* 71 * Item destructor 72 * 73 * Arguments: 74 * item A pointer to the memory which has been allocated. 75 * size The size of the item being destructed. 76 * arg Argument passed through uma_zfree_arg 77 * 78 * Returns: 79 * Nothing 80 * 81 * Discussion: 82 * The destructor may perform operations that differ from those performed 83 * by the initializer, but it must leave the object in the same state. 84 * This IS type stable storage. This is called after EVERY zfree call. 85 */ 86 typedef void (*uma_dtor)(void *mem, int size, void *arg); 87 88 /* 89 * Item initializer 90 * 91 * Arguments: 92 * item A pointer to the memory which has been allocated. 93 * size The size of the item being initialized. 94 * flags See zalloc flags 95 * 96 * Returns: 97 * 0 on success 98 * errno on failure 99 * 100 * Discussion: 101 * The initializer is called when the memory is cached in the uma zone. 102 * this should be the same state that the destructor leaves the object in. 103 */ 104 typedef int (*uma_init)(void *mem, int size, int flags); 105 106 /* 107 * Item discard function 108 * 109 * Arguments: 110 * item A pointer to memory which has been 'freed' but has not left the 111 * zone's cache. 112 * size The size of the item being discarded. 113 * 114 * Returns: 115 * Nothing 116 * 117 * Discussion: 118 * This routine is called when memory leaves a zone and is returned to the 119 * system for other uses. It is the counter part to the init function. 120 */ 121 typedef void (*uma_fini)(void *mem, int size); 122 123 /* 124 * What's the difference between initializing and constructing? 125 * 126 * The item is initialized when it is cached, and this is the state that the 127 * object should be in when returned to the allocator. The purpose of this is 128 * to remove some code which would otherwise be called on each allocation by 129 * utilizing a known, stable state. This differs from the constructor which 130 * will be called on EVERY allocation. 131 * 132 * For example, in the initializer you may want to initialize embeded locks, 133 * NULL list pointers, set up initial states, magic numbers, etc. This way if 134 * the object is held in the allocator and re-used it won't be necessary to 135 * re-initialize it. 136 * 137 * The constructor may be used to lock a data structure, link it on to lists, 138 * bump reference counts or total counts of outstanding structures, etc. 139 * 140 */ 141 142 143 /* Function proto types */ 144 145 /* 146 * Create a new uma zone 147 * 148 * Arguments: 149 * name The text name of the zone for debugging and stats, this memory 150 * should not be freed until the zone has been deallocated. 151 * size The size of the object that is being created. 152 * ctor The constructor that is called when the object is allocated 153 * dtor The destructor that is called when the object is freed. 154 * init An initializer that sets up the initial state of the memory. 155 * fini A discard function that undoes initialization done by init. 156 * ctor/dtor/init/fini may all be null, see notes above. 157 * align A bitmask that corisponds to the requested alignment 158 * eg 4 would be 0x3 159 * flags A set of parameters that control the behavior of the zone 160 * 161 * Returns: 162 * A pointer to a structure which is intended to be opaque to users of 163 * the interface. The value may be null if the wait flag is not set. 164 */ 165 uma_zone_t uma_zcreate(char *name, size_t size, uma_ctor ctor, uma_dtor dtor, 166 uma_init uminit, uma_fini fini, int align, 167 u_int32_t flags); 168 169 /* 170 * Create a secondary uma zone 171 * 172 * Arguments: 173 * name The text name of the zone for debugging and stats, this memory 174 * should not be freed until the zone has been deallocated. 175 * ctor The constructor that is called when the object is allocated 176 * dtor The destructor that is called when the object is freed. 177 * zinit An initializer that sets up the initial state of the memory 178 * as the object passes from the Keg's slab to the Zone's cache. 179 * zfini A discard function that undoes initialization done by init 180 * as the object passes from the Zone's cache to the Keg's slab. 181 * 182 * ctor/dtor/zinit/zfini may all be null, see notes above. 183 * Note that the zinit and zfini specified here are NOT 184 * exactly the same as the init/fini specified to uma_zcreate() 185 * when creating a master zone. These zinit/zfini are called 186 * on the TRANSITION from keg to zone (and vice-versa). Once 187 * these are set, the primary zone may alter its init/fini 188 * (which are called when the object passes from VM to keg) 189 * using uma_zone_set_init/fini()) as well as its own 190 * zinit/zfini (unset by default for master zone) with 191 * uma_zone_set_zinit/zfini() (note subtle 'z' prefix). 192 * 193 * master A reference to this zone's Master Zone (Primary Zone), 194 * which contains the backing Keg for the Secondary Zone 195 * being added. 196 * 197 * Returns: 198 * A pointer to a structure which is intended to be opaque to users of 199 * the interface. The value may be null if the wait flag is not set. 200 */ 201 uma_zone_t uma_zsecond_create(char *name, uma_ctor ctor, uma_dtor dtor, 202 uma_init zinit, uma_fini zfini, uma_zone_t master); 203 204 /* 205 * Definitions for uma_zcreate flags 206 * 207 * These flags share space with UMA_ZFLAGs in uma_int.h. Be careful not to 208 * overlap when adding new features. 0xf0000000 is in use by uma_int.h. 209 */ 210 #define UMA_ZONE_PAGEABLE 0x0001 /* Return items not fully backed by 211 physical memory XXX Not yet */ 212 #define UMA_ZONE_ZINIT 0x0002 /* Initialize with zeros */ 213 #define UMA_ZONE_STATIC 0x0004 /* Staticly sized zone */ 214 #define UMA_ZONE_OFFPAGE 0x0008 /* Force the slab structure allocation 215 off of the real memory */ 216 #define UMA_ZONE_MALLOC 0x0010 /* For use by malloc(9) only! */ 217 #define UMA_ZONE_NOFREE 0x0020 /* Do not free slabs of this type! */ 218 #define UMA_ZONE_MTXCLASS 0x0040 /* Create a new lock class */ 219 #define UMA_ZONE_VM 0x0080 /* 220 * Used for internal vm datastructures 221 * only. 222 */ 223 #define UMA_ZONE_HASH 0x0100 /* 224 * Use a hash table instead of caching 225 * information in the vm_page. 226 */ 227 #define UMA_ZONE_SECONDARY 0x0200 /* Zone is a Secondary Zone */ 228 #define UMA_ZONE_REFCNT 0x0400 /* Allocate refcnts in slabs */ 229 #define UMA_ZONE_MAXBUCKET 0x0800 /* Use largest buckets */ 230 231 /* Definitions for align */ 232 #define UMA_ALIGN_PTR (sizeof(void *) - 1) /* Alignment fit for ptr */ 233 #define UMA_ALIGN_LONG (sizeof(long) - 1) /* "" long */ 234 #define UMA_ALIGN_INT (sizeof(int) - 1) /* "" int */ 235 #define UMA_ALIGN_SHORT (sizeof(short) - 1) /* "" short */ 236 #define UMA_ALIGN_CHAR (sizeof(char) - 1) /* "" char */ 237 #define UMA_ALIGN_CACHE (16 - 1) /* Cache line size align */ 238 239 /* 240 * Destroys an empty uma zone. If the zone is not empty uma complains loudly. 241 * 242 * Arguments: 243 * zone The zone we want to destroy. 244 * 245 */ 246 void uma_zdestroy(uma_zone_t zone); 247 248 /* 249 * Allocates an item out of a zone 250 * 251 * Arguments: 252 * zone The zone we are allocating from 253 * arg This data is passed to the ctor function 254 * flags See sys/malloc.h for available flags. 255 * 256 * Returns: 257 * A non null pointer to an initialized element from the zone is 258 * garanteed if the wait flag is M_WAITOK, otherwise a null pointer may be 259 * returned if the zone is empty or the ctor failed. 260 */ 261 262 void *uma_zalloc_arg(uma_zone_t zone, void *arg, int flags); 263 264 /* 265 * Allocates an item out of a zone without supplying an argument 266 * 267 * This is just a wrapper for uma_zalloc_arg for convenience. 268 * 269 */ 270 static __inline void *uma_zalloc(uma_zone_t zone, int flags); 271 272 static __inline void * 273 uma_zalloc(uma_zone_t zone, int flags) 274 { 275 return uma_zalloc_arg(zone, NULL, flags); 276 } 277 278 /* 279 * Frees an item back into the specified zone. 280 * 281 * Arguments: 282 * zone The zone the item was originally allocated out of. 283 * item The memory to be freed. 284 * arg Argument passed to the destructor 285 * 286 * Returns: 287 * Nothing. 288 */ 289 290 void uma_zfree_arg(uma_zone_t zone, void *item, void *arg); 291 292 /* 293 * Frees an item back to a zone without supplying an argument 294 * 295 * This is just a wrapper for uma_zfree_arg for convenience. 296 * 297 */ 298 static __inline void uma_zfree(uma_zone_t zone, void *item); 299 300 static __inline void 301 uma_zfree(uma_zone_t zone, void *item) 302 { 303 uma_zfree_arg(zone, item, NULL); 304 } 305 306 /* 307 * XXX The rest of the prototypes in this header are h0h0 magic for the VM. 308 * If you think you need to use it for a normal zone you're probably incorrect. 309 */ 310 311 /* 312 * Backend page supplier routines 313 * 314 * Arguments: 315 * zone The zone that is requesting pages 316 * size The number of bytes being requested 317 * pflag Flags for these memory pages, see below. 318 * wait Indicates our willingness to block. 319 * 320 * Returns: 321 * A pointer to the alloced memory or NULL on failure. 322 */ 323 324 typedef void *(*uma_alloc)(uma_zone_t zone, int size, u_int8_t *pflag, int wait); 325 326 /* 327 * Backend page free routines 328 * 329 * Arguments: 330 * item A pointer to the previously allocated pages 331 * size The original size of the allocation 332 * pflag The flags for the slab. See UMA_SLAB_* below 333 * 334 * Returns: 335 * None 336 */ 337 typedef void (*uma_free)(void *item, int size, u_int8_t pflag); 338 339 340 341 /* 342 * Sets up the uma allocator. (Called by vm_mem_init) 343 * 344 * Arguments: 345 * bootmem A pointer to memory used to bootstrap the system. 346 * 347 * Returns: 348 * Nothing 349 * 350 * Discussion: 351 * This memory is used for zones which allocate things before the 352 * backend page supplier can give us pages. It should be 353 * UMA_SLAB_SIZE * boot_pages bytes. (see uma_int.h) 354 * 355 */ 356 357 void uma_startup(void *bootmem, int boot_pages); 358 359 /* 360 * Finishes starting up the allocator. This should 361 * be called when kva is ready for normal allocs. 362 * 363 * Arguments: 364 * None 365 * 366 * Returns: 367 * Nothing 368 * 369 * Discussion: 370 * uma_startup2 is called by kmeminit() to enable us of uma for malloc. 371 */ 372 373 void uma_startup2(void); 374 375 /* 376 * Reclaims unused memory for all zones 377 * 378 * Arguments: 379 * None 380 * Returns: 381 * None 382 * 383 * This should only be called by the page out daemon. 384 */ 385 386 void uma_reclaim(void); 387 388 /* 389 * Switches the backing object of a zone 390 * 391 * Arguments: 392 * zone The zone to update 393 * obj The obj to use for future allocations 394 * size The size of the object to allocate 395 * 396 * Returns: 397 * 0 if kva space can not be allocated 398 * 1 if successful 399 * 400 * Discussion: 401 * A NULL object can be used and uma will allocate one for you. Setting 402 * the size will limit the amount of memory allocated to this zone. 403 * 404 */ 405 struct vm_object; 406 int uma_zone_set_obj(uma_zone_t zone, struct vm_object *obj, int size); 407 408 /* 409 * Sets a high limit on the number of items allowed in a zone 410 * 411 * Arguments: 412 * zone The zone to limit 413 * 414 * Returns: 415 * Nothing 416 */ 417 void uma_zone_set_max(uma_zone_t zone, int nitems); 418 419 /* 420 * The following two routines (uma_zone_set_init/fini) 421 * are used to set the backend init/fini pair which acts on an 422 * object as it becomes allocated and is placed in a slab within 423 * the specified zone's backing keg. These should probably not 424 * be changed once allocations have already begun and only 425 * immediately upon zone creation. 426 */ 427 void uma_zone_set_init(uma_zone_t zone, uma_init uminit); 428 void uma_zone_set_fini(uma_zone_t zone, uma_fini fini); 429 430 /* 431 * The following two routines (uma_zone_set_zinit/zfini) are 432 * used to set the zinit/zfini pair which acts on an object as 433 * it passes from the backing Keg's slab cache to the 434 * specified Zone's bucket cache. These should probably not 435 * be changed once allocations have already begun and 436 * only immediately upon zone creation. 437 */ 438 void uma_zone_set_zinit(uma_zone_t zone, uma_init zinit); 439 void uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini); 440 441 /* 442 * Replaces the standard page_alloc or obj_alloc functions for this zone 443 * 444 * Arguments: 445 * zone The zone whos back end allocator is being changed. 446 * allocf A pointer to the allocation function 447 * 448 * Returns: 449 * Nothing 450 * 451 * Discussion: 452 * This could be used to implement pageable allocation, or perhaps 453 * even DMA allocators if used in conjunction with the OFFPAGE 454 * zone flag. 455 */ 456 457 void uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf); 458 459 /* 460 * Used for freeing memory provided by the allocf above 461 * 462 * Arguments: 463 * zone The zone that intends to use this free routine. 464 * freef The page freeing routine. 465 * 466 * Returns: 467 * Nothing 468 */ 469 470 void uma_zone_set_freef(uma_zone_t zone, uma_free freef); 471 472 /* 473 * These flags are setable in the allocf and visable in the freef. 474 */ 475 #define UMA_SLAB_BOOT 0x01 /* Slab alloced from boot pages */ 476 #define UMA_SLAB_KMEM 0x02 /* Slab alloced from kmem_map */ 477 #define UMA_SLAB_PRIV 0x08 /* Slab alloced from priv allocator */ 478 #define UMA_SLAB_OFFP 0x10 /* Slab is managed separately */ 479 #define UMA_SLAB_MALLOC 0x20 /* Slab is a large malloc slab */ 480 /* 0x40 and 0x80 are available */ 481 482 /* 483 * Used to pre-fill a zone with some number of items 484 * 485 * Arguments: 486 * zone The zone to fill 487 * itemcnt The number of items to reserve 488 * 489 * Returns: 490 * Nothing 491 * 492 * NOTE: This is blocking and should only be done at startup 493 */ 494 void uma_prealloc(uma_zone_t zone, int itemcnt); 495 496 /* 497 * Used to lookup the reference counter allocated for an item 498 * from a UMA_ZONE_REFCNT zone. For UMA_ZONE_REFCNT zones, 499 * reference counters are allocated for items and stored in 500 * the underlying slab header. 501 * 502 * Arguments: 503 * zone The UMA_ZONE_REFCNT zone to which the item belongs. 504 * item The address of the item for which we want a refcnt. 505 * 506 * Returns: 507 * A pointer to a u_int32_t reference counter. 508 */ 509 u_int32_t *uma_find_refcnt(uma_zone_t zone, void *item); 510 511 /* 512 * Exported statistics structures to be used by user space monitoring tools. 513 * Statistics stream consusts of a uma_stream_header, followed by a series of 514 * alternative uma_type_header and uma_type_stat structures. Statistics 515 * structures 516 */ 517 #define UMA_STREAM_VERSION 0x00000001 518 struct uma_stream_header { 519 u_int32_t ush_version; /* Stream format version. */ 520 u_int32_t ush_maxcpus; /* Value of MAXCPU for stream. */ 521 u_int32_t ush_count; /* Number of records. */ 522 u_int32_t _ush_pad; /* Pad/reserved field. */ 523 }; 524 525 #define UTH_MAX_NAME 32 526 #define UTH_ZONE_SECONDARY 0x00000001 527 struct uma_type_header { 528 /* 529 * Static per-zone data, some extracted from the supporting keg. 530 */ 531 char uth_name[UTH_MAX_NAME]; 532 u_int32_t uth_align; /* Keg: alignment. */ 533 u_int32_t uth_size; /* Keg: requested size of item. */ 534 u_int32_t uth_rsize; /* Keg: real size of item. */ 535 u_int32_t uth_maxpages; /* Keg: maximum number of pages. */ 536 u_int32_t uth_limit; /* Keg: max items to allocate. */ 537 538 /* 539 * Current dynamic zone/keg-derived statistics. 540 */ 541 u_int32_t uth_pages; /* Keg: pages allocated. */ 542 u_int32_t uth_keg_free; /* Keg: items free. */ 543 u_int32_t uth_zone_free; /* Zone: items free. */ 544 u_int32_t uth_bucketsize; /* Zone: desired bucket size. */ 545 u_int32_t uth_zone_flags; /* Zone: flags. */ 546 u_int64_t uth_allocs; /* Zone: number of allocations. */ 547 u_int64_t uth_frees; /* Zone: number of frees. */ 548 u_int64_t uth_fails; /* Zone: number of alloc failures. */ 549 u_int64_t _uth_reserved1[3]; /* Reserved. */ 550 }; 551 552 struct uma_percpu_stat { 553 u_int64_t ups_allocs; /* Cache: number of alloctions. */ 554 u_int64_t ups_frees; /* Cache: number of frees. */ 555 u_int64_t ups_cache_free; /* Cache: free items in cache. */ 556 u_int64_t _ups_reserved[5]; /* Reserved. */ 557 }; 558 559 #endif 560