2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (c) 2002, 2003, 2004, 2005 Jeffrey Roberson <jeff@FreeBSD.org>
5 * Copyright (c) 2004, 2005 Bosko Milekic <bmilekic@FreeBSD.org>
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice unmodified, this list of conditions, and the following
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 * uma.h - External definitions for the Universal Memory Allocator
41 #include <sys/param.h> /* For NULL */
42 #include <sys/malloc.h> /* For M_* */
45 /* User visible parameters */
46 #define UMA_SMALLEST_UNIT 8 /* Smallest item allocated */
48 /* Types and type defs */
51 /* Opaque type used as a handle to the zone */
52 typedef struct uma_zone * uma_zone_t;
58 * item A pointer to the memory which has been allocated.
59 * arg The arg field passed to uma_zalloc_arg
60 * size The size of the allocated item
61 * flags See zalloc flags
68 * The constructor is called just before the memory is returned
69 * to the user. It may block if necessary.
71 typedef int (*uma_ctor)(void *mem, int size, void *arg, int flags);
77 * item A pointer to the memory which has been allocated.
78 * size The size of the item being destructed.
79 * arg Argument passed through uma_zfree_arg
85 * The destructor may perform operations that differ from those performed
86 * by the initializer, but it must leave the object in the same state.
87 * This IS type stable storage. This is called after EVERY zfree call.
89 typedef void (*uma_dtor)(void *mem, int size, void *arg);
95 * item A pointer to the memory which has been allocated.
96 * size The size of the item being initialized.
97 * flags See zalloc flags
104 * The initializer is called when the memory is cached in the uma zone.
105 * The initializer and the destructor should leave the object in the same
108 typedef int (*uma_init)(void *mem, int size, int flags);
111 * Item discard function
114 * item A pointer to memory which has been 'freed' but has not left the
116 * size The size of the item being discarded.
122 * This routine is called when memory leaves a zone and is returned to the
123 * system for other uses. It is the counter-part to the init function.
125 typedef void (*uma_fini)(void *mem, int size);
128 * Import new memory into a cache zone.
130 typedef int (*uma_import)(void *arg, void **store, int count, int domain,
134 * Free memory from a cache zone.
136 typedef void (*uma_release)(void *arg, void **store, int count);
139 * What's the difference between initializing and constructing?
141 * The item is initialized when it is cached, and this is the state that the
142 * object should be in when returned to the allocator. The purpose of this is
143 * to remove some code which would otherwise be called on each allocation by
144 * utilizing a known, stable state. This differs from the constructor which
145 * will be called on EVERY allocation.
147 * For example, in the initializer you may want to initialize embedded locks,
148 * NULL list pointers, set up initial states, magic numbers, etc. This way if
149 * the object is held in the allocator and re-used it won't be necessary to
152 * The constructor may be used to lock a data structure, link it on to lists,
153 * bump reference counts or total counts of outstanding structures, etc.
157 /* Function proto types */
160 * Create a new uma zone
163 * name The text name of the zone for debugging and stats. This memory
164 * should not be freed until the zone has been deallocated.
165 * size The size of the object that is being created.
166 * ctor The constructor that is called when the object is allocated.
167 * dtor The destructor that is called when the object is freed.
168 * init An initializer that sets up the initial state of the memory.
169 * fini A discard function that undoes initialization done by init.
170 * ctor/dtor/init/fini may all be null, see notes above.
171 * align A bitmask that corresponds to the requested alignment
173 * flags A set of parameters that control the behavior of the zone.
176 * A pointer to a structure which is intended to be opaque to users of
177 * the interface. The value may be null if the wait flag is not set.
179 uma_zone_t uma_zcreate(const char *name, size_t size, uma_ctor ctor,
180 uma_dtor dtor, uma_init uminit, uma_fini fini,
181 int align, uint32_t flags);
184 * Create a secondary uma zone
187 * name The text name of the zone for debugging and stats. This memory
188 * should not be freed until the zone has been deallocated.
189 * ctor The constructor that is called when the object is allocated.
190 * dtor The destructor that is called when the object is freed.
191 * zinit An initializer that sets up the initial state of the memory
192 * as the object passes from the Keg's slab to the Zone's cache.
193 * zfini A discard function that undoes initialization done by init
194 * as the object passes from the Zone's cache to the Keg's slab.
196 * ctor/dtor/zinit/zfini may all be null, see notes above.
197 * Note that the zinit and zfini specified here are NOT
198 * exactly the same as the init/fini specified to uma_zcreate()
199 * when creating a primary zone. These zinit/zfini are called
200 * on the TRANSITION from keg to zone (and vice-versa). Once
201 * these are set, the primary zone may alter its init/fini
202 * (which are called when the object passes from VM to keg)
203 * using uma_zone_set_init/fini()) as well as its own
204 * zinit/zfini (unset by default for primary zone) with
205 * uma_zone_set_zinit/zfini() (note subtle 'z' prefix).
207 * primary A reference to this zone's Primary Zone which contains the
208 * backing Keg for the Secondary Zone being added.
211 * A pointer to a structure which is intended to be opaque to users of
212 * the interface. The value may be null if the wait flag is not set.
214 uma_zone_t uma_zsecond_create(const char *name, uma_ctor ctor, uma_dtor dtor,
215 uma_init zinit, uma_fini zfini, uma_zone_t primary);
218 * Create cache-only zones.
220 * This allows uma's per-cpu cache facilities to handle arbitrary
221 * pointers. Consumers must specify the import and release functions to
222 * fill and destroy caches. UMA does not allocate any memory for these
223 * zones. The 'arg' parameter is passed to import/release and is caller
226 uma_zone_t uma_zcache_create(const char *name, int size, uma_ctor ctor,
227 uma_dtor dtor, uma_init zinit, uma_fini zfini, uma_import zimport,
228 uma_release zrelease, void *arg, int flags);
231 * Definitions for uma_zcreate flags
233 * These flags share space with UMA_ZFLAGs in uma_int.h. Be careful not to
234 * overlap when adding new features.
236 #define UMA_ZONE_UNMANAGED 0x0001 /*
237 * Don't regulate the cache size, even
238 * under memory pressure.
240 #define UMA_ZONE_ZINIT 0x0002 /* Initialize with zeros */
241 #define UMA_ZONE_CONTIG 0x0004 /*
242 * Physical memory underlying an object
243 * must be contiguous.
245 #define UMA_ZONE_NOTOUCH 0x0008 /* UMA may not access the memory */
246 #define UMA_ZONE_MALLOC 0x0010 /* For use by malloc(9) only! */
247 #define UMA_ZONE_NOFREE 0x0020 /* Do not free slabs of this type! */
248 #define UMA_ZONE_MTXCLASS 0x0040 /* Create a new lock class */
249 #define UMA_ZONE_VM 0x0080 /*
250 * Used for internal vm datastructures
253 #define UMA_ZONE_NOTPAGE 0x0100 /* allocf memory not vm pages */
254 #define UMA_ZONE_SECONDARY 0x0200 /* Zone is a Secondary Zone */
255 #define UMA_ZONE_NOBUCKET 0x0400 /* Do not use buckets. */
256 #define UMA_ZONE_MAXBUCKET 0x0800 /* Use largest buckets. */
257 #define UMA_ZONE_CACHESPREAD 0x2000 /*
258 * Spread memory start locations across
259 * all possible cache lines. May
260 * require many virtually contiguous
261 * backend pages and can fail early.
263 #define UMA_ZONE_NODUMP 0x4000 /*
264 * Zone's pages will not be included in
267 #define UMA_ZONE_PCPU 0x8000 /*
268 * Allocates mp_maxid + 1 slabs of
271 #define UMA_ZONE_FIRSTTOUCH 0x10000 /* First touch NUMA policy */
272 #define UMA_ZONE_ROUNDROBIN 0x20000 /* Round-robin NUMA policy. */
273 #define UMA_ZONE_SMR 0x40000 /*
274 * Safe memory reclamation defers
275 * frees until all read sections
276 * have exited. This flag creates
277 * a unique SMR context for this
278 * zone. To share contexts see
279 * uma_zone_set_smr() below.
281 * See sys/smr.h for more details.
283 #define UMA_ZONE_NOKASAN 0x80000 /*
284 * Disable KASAN verification. This is
285 * implied by NOFREE. Cache zones are
286 * not verified by default.
288 /* In use by UMA_ZFLAGs: 0xffe00000 */
291 * These flags are shared between the keg and zone. Some are determined
292 * based on physical parameters of the request and may not be provided by
295 #define UMA_ZONE_INHERIT \
296 (UMA_ZONE_NOTOUCH | UMA_ZONE_MALLOC | UMA_ZONE_NOFREE | \
297 UMA_ZONE_VM | UMA_ZONE_NOTPAGE | UMA_ZONE_PCPU | \
298 UMA_ZONE_FIRSTTOUCH | UMA_ZONE_ROUNDROBIN | UMA_ZONE_NOKASAN)
300 /* Definitions for align */
301 #define UMA_ALIGN_PTR (sizeof(void *) - 1) /* Alignment fit for ptr */
302 #define UMA_ALIGN_LONG (sizeof(long) - 1) /* "" long */
303 #define UMA_ALIGN_INT (sizeof(int) - 1) /* "" int */
304 #define UMA_ALIGN_SHORT (sizeof(short) - 1) /* "" short */
305 #define UMA_ALIGN_CHAR (sizeof(char) - 1) /* "" char */
306 #define UMA_ALIGN_CACHE (0 - 1) /* Cache line size align */
307 #define UMA_ALIGNOF(type) (_Alignof(type) - 1) /* Alignment fit for 'type' */
309 #define UMA_ANYDOMAIN -1 /* Special value for domain search. */
312 * Destroys an empty uma zone. If the zone is not empty uma complains loudly.
315 * zone The zone we want to destroy.
318 void uma_zdestroy(uma_zone_t zone);
321 * Allocates an item out of a zone
324 * zone The zone we are allocating from
325 * arg This data is passed to the ctor function
326 * flags See sys/malloc.h for available flags.
329 * A non-null pointer to an initialized element from the zone is
330 * guaranteed if the wait flag is M_WAITOK. Otherwise a null pointer
331 * may be returned if the zone is empty or the ctor failed.
334 void *uma_zalloc_arg(uma_zone_t zone, void *arg, int flags);
336 /* Allocate per-cpu data. Access the correct data with zpcpu_get(). */
337 void *uma_zalloc_pcpu_arg(uma_zone_t zone, void *arg, int flags);
339 /* Use with SMR zones. */
340 void *uma_zalloc_smr(uma_zone_t zone, int flags);
343 * Allocate an item from a specific NUMA domain. This uses a slow path in
344 * the allocator but is guaranteed to allocate memory from the requested
345 * domain if M_WAITOK is set.
348 * zone The zone we are allocating from
349 * arg This data is passed to the ctor function
350 * domain The domain to allocate from.
351 * flags See sys/malloc.h for available flags.
353 void *uma_zalloc_domain(uma_zone_t zone, void *arg, int domain, int flags);
356 * Allocates an item out of a zone without supplying an argument
358 * This is just a wrapper for uma_zalloc_arg for convenience.
361 static __inline void *uma_zalloc(uma_zone_t zone, int flags);
362 static __inline void *uma_zalloc_pcpu(uma_zone_t zone, int flags);
364 static __inline void *
365 uma_zalloc(uma_zone_t zone, int flags)
367 return uma_zalloc_arg(zone, NULL, flags);
370 static __inline void *
371 uma_zalloc_pcpu(uma_zone_t zone, int flags)
373 return uma_zalloc_pcpu_arg(zone, NULL, flags);
377 * Frees an item back into the specified zone.
380 * zone The zone the item was originally allocated out of.
381 * item The memory to be freed.
382 * arg Argument passed to the destructor
388 void uma_zfree_arg(uma_zone_t zone, void *item, void *arg);
390 /* Use with PCPU zones. */
391 void uma_zfree_pcpu_arg(uma_zone_t zone, void *item, void *arg);
393 /* Use with SMR zones. */
394 void uma_zfree_smr(uma_zone_t zone, void *item);
397 * Frees an item back to a zone without supplying an argument
399 * This is just a wrapper for uma_zfree_arg for convenience.
402 static __inline void uma_zfree(uma_zone_t zone, void *item);
403 static __inline void uma_zfree_pcpu(uma_zone_t zone, void *item);
406 uma_zfree(uma_zone_t zone, void *item)
408 uma_zfree_arg(zone, item, NULL);
412 uma_zfree_pcpu(uma_zone_t zone, void *item)
414 uma_zfree_pcpu_arg(zone, item, NULL);
418 * Wait until the specified zone can allocate an item.
420 void uma_zwait(uma_zone_t zone);
423 * Backend page supplier routines
426 * zone The zone that is requesting pages.
427 * size The number of bytes being requested.
428 * pflag Flags for these memory pages, see below.
429 * domain The NUMA domain that we prefer for this allocation.
430 * wait Indicates our willingness to block.
433 * A pointer to the allocated memory or NULL on failure.
436 typedef void *(*uma_alloc)(uma_zone_t zone, vm_size_t size, int domain,
437 uint8_t *pflag, int wait);
440 * Backend page free routines
443 * item A pointer to the previously allocated pages.
444 * size The original size of the allocation.
445 * pflag The flags for the slab. See UMA_SLAB_* below.
450 typedef void (*uma_free)(void *item, vm_size_t size, uint8_t pflag);
453 * Reclaims unused memory. If no NUMA domain is specified, memory from all
454 * domains is reclaimed.
457 * req Reclamation request type.
458 * domain The target NUMA domain.
462 #define UMA_RECLAIM_DRAIN 1 /* release bucket cache */
463 #define UMA_RECLAIM_DRAIN_CPU 2 /* release bucket and per-CPU caches */
464 #define UMA_RECLAIM_TRIM 3 /* trim bucket cache to WSS */
465 void uma_reclaim(int req);
466 void uma_reclaim_domain(int req, int domain);
467 void uma_zone_reclaim(uma_zone_t, int req);
468 void uma_zone_reclaim_domain(uma_zone_t, int req, int domain);
471 * Sets the alignment mask to be used for all zones requesting cache
472 * alignment. Should be called by MD boot code prior to starting VM/UMA.
475 * align The alignment mask
480 void uma_set_align(int align);
483 * Set a reserved number of items to hold for M_USE_RESERVE allocations. All
484 * other requests must allocate new backing pages.
486 void uma_zone_reserve(uma_zone_t zone, int nitems);
489 * Reserves the maximum KVA space required by the zone and configures the zone
490 * to use a backend that allocates physical memory and maps it using the
494 * zone The zone to update.
495 * nitems The upper limit on the number of items that can be allocated.
498 * 0 if KVA space can not be allocated
502 * When the machine supports a direct map and the zone's items are smaller
503 * than a page, the zone will use the direct map instead of allocating KVA
506 int uma_zone_reserve_kva(uma_zone_t zone, int nitems);
509 * Sets an upper limit on the number of items allocated from a zone
512 * zone The zone to limit
513 * nitems The requested upper limit on the number of items allowed
516 * int The effective value of nitems
518 int uma_zone_set_max(uma_zone_t zone, int nitems);
521 * Sets an upper limit on the number of items allowed in zone's caches
524 * zone The zone to limit
525 * nitems The requested upper limit on the number of items allowed
527 void uma_zone_set_maxcache(uma_zone_t zone, int nitems);
530 * Obtains the effective limit on the number of items in a zone
533 * zone The zone to obtain the effective limit from
537 * int The effective limit of the zone
539 int uma_zone_get_max(uma_zone_t zone);
542 * Sets a warning to be printed when limit is reached
545 * zone The zone we will warn about
546 * warning Warning content
551 void uma_zone_set_warning(uma_zone_t zone, const char *warning);
554 * Sets a function to run when limit is reached
557 * zone The zone to which this applies
558 * fx The function ro run
563 typedef void (*uma_maxaction_t)(uma_zone_t, int);
564 void uma_zone_set_maxaction(uma_zone_t zone, uma_maxaction_t);
567 * Obtains the approximate current number of items allocated from a zone
570 * zone The zone to obtain the current allocation count from
573 * int The approximate current number of items allocated from the zone
575 int uma_zone_get_cur(uma_zone_t zone);
578 * The following two routines (uma_zone_set_init/fini)
579 * are used to set the backend init/fini pair which acts on an
580 * object as it becomes allocated and is placed in a slab within
581 * the specified zone's backing keg. These should probably not
582 * be changed once allocations have already begun, but only be set
583 * immediately upon zone creation.
585 void uma_zone_set_init(uma_zone_t zone, uma_init uminit);
586 void uma_zone_set_fini(uma_zone_t zone, uma_fini fini);
589 * The following two routines (uma_zone_set_zinit/zfini) are
590 * used to set the zinit/zfini pair which acts on an object as
591 * it passes from the backing Keg's slab cache to the
592 * specified Zone's bucket cache. These should probably not
593 * be changed once allocations have already begun, but only be set
594 * immediately upon zone creation.
596 void uma_zone_set_zinit(uma_zone_t zone, uma_init zinit);
597 void uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini);
600 * Replaces the standard backend allocator for this zone.
603 * zone The zone whose backend allocator is being changed.
604 * allocf A pointer to the allocation function
610 * This could be used to implement pageable allocation, or perhaps
611 * even DMA allocators if used in conjunction with the OFFPAGE
615 void uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf);
618 * Used for freeing memory provided by the allocf above
621 * zone The zone that intends to use this free routine.
622 * freef The page freeing routine.
628 void uma_zone_set_freef(uma_zone_t zone, uma_free freef);
631 * Associate a zone with a smr context that is allocated after creation
632 * so that multiple zones may share the same context.
634 void uma_zone_set_smr(uma_zone_t zone, smr_t smr);
637 * Fetch the smr context that was set or made in uma_zcreate().
639 smr_t uma_zone_get_smr(uma_zone_t zone);
642 * These flags are setable in the allocf and visible in the freef.
644 #define UMA_SLAB_BOOT 0x01 /* Slab alloced from boot pages */
645 #define UMA_SLAB_KERNEL 0x04 /* Slab alloced from kmem */
646 #define UMA_SLAB_PRIV 0x08 /* Slab alloced from priv allocator */
647 /* 0x02, 0x10, 0x40, and 0x80 are available */
650 * Used to pre-fill a zone with some number of items
653 * zone The zone to fill
654 * itemcnt The number of items to reserve
659 * NOTE: This is blocking and should only be done at startup
661 void uma_prealloc(uma_zone_t zone, int itemcnt);
664 * Used to determine if a fixed-size zone is exhausted.
667 * zone The zone to check
670 * Non-zero if zone is exhausted.
672 int uma_zone_exhausted(uma_zone_t zone);
675 * Returns the bytes of memory consumed by the zone.
677 size_t uma_zone_memory(uma_zone_t zone);
680 * Common UMA_ZONE_PCPU zones.
682 extern uma_zone_t pcpu_zone_4;
683 extern uma_zone_t pcpu_zone_8;
684 extern uma_zone_t pcpu_zone_16;
685 extern uma_zone_t pcpu_zone_32;
686 extern uma_zone_t pcpu_zone_64;
689 * Exported statistics structures to be used by user space monitoring tools.
690 * Statistics stream consists of a uma_stream_header, followed by a series of
691 * alternative uma_type_header and uma_type_stat structures.
693 #define UMA_STREAM_VERSION 0x00000001
694 struct uma_stream_header {
695 uint32_t ush_version; /* Stream format version. */
696 uint32_t ush_maxcpus; /* Value of MAXCPU for stream. */
697 uint32_t ush_count; /* Number of records. */
698 uint32_t _ush_pad; /* Pad/reserved field. */
701 #define UTH_MAX_NAME 32
702 #define UTH_ZONE_SECONDARY 0x00000001
703 struct uma_type_header {
705 * Static per-zone data, some extracted from the supporting keg.
707 char uth_name[UTH_MAX_NAME];
708 uint32_t uth_align; /* Keg: alignment. */
709 uint32_t uth_size; /* Keg: requested size of item. */
710 uint32_t uth_rsize; /* Keg: real size of item. */
711 uint32_t uth_maxpages; /* Keg: maximum number of pages. */
712 uint32_t uth_limit; /* Keg: max items to allocate. */
715 * Current dynamic zone/keg-derived statistics.
717 uint32_t uth_pages; /* Keg: pages allocated. */
718 uint32_t uth_keg_free; /* Keg: items free. */
719 uint32_t uth_zone_free; /* Zone: items free. */
720 uint32_t uth_bucketsize; /* Zone: desired bucket size. */
721 uint32_t uth_zone_flags; /* Zone: flags. */
722 uint64_t uth_allocs; /* Zone: number of allocations. */
723 uint64_t uth_frees; /* Zone: number of frees. */
724 uint64_t uth_fails; /* Zone: number of alloc failures. */
725 uint64_t uth_sleeps; /* Zone: number of alloc sleeps. */
726 uint64_t uth_xdomain; /* Zone: Number of cross domain frees. */
727 uint64_t _uth_reserved1[1]; /* Reserved. */
730 struct uma_percpu_stat {
731 uint64_t ups_allocs; /* Cache: number of allocations. */
732 uint64_t ups_frees; /* Cache: number of frees. */
733 uint64_t ups_cache_free; /* Cache: free items in cache. */
734 uint64_t _ups_reserved[5]; /* Reserved. */
737 void uma_reclaim_wakeup(void);
738 void uma_reclaim_worker(void *);
740 unsigned long uma_limit(void);
742 /* Return the amount of memory managed by UMA. */
743 unsigned long uma_size(void);
745 /* Return the amount of memory remaining. May be negative. */
746 long uma_avail(void);
748 #endif /* _VM_UMA_H_ */