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,
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25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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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_ZINIT 0x0002 /* Initialize with zeros */
237 #define UMA_ZONE_CONTIG 0x0004 /*
238 * Physical memory underlying an object
239 * must be contiguous.
241 #define UMA_ZONE_NOTOUCH 0x0008 /* UMA may not access the memory */
242 #define UMA_ZONE_MALLOC 0x0010 /* For use by malloc(9) only! */
243 #define UMA_ZONE_NOFREE 0x0020 /* Do not free slabs of this type! */
244 #define UMA_ZONE_MTXCLASS 0x0040 /* Create a new lock class */
245 #define UMA_ZONE_VM 0x0080 /*
246 * Used for internal vm datastructures
249 #define UMA_ZONE_NOTPAGE 0x0100 /* allocf memory not vm pages */
250 #define UMA_ZONE_SECONDARY 0x0200 /* Zone is a Secondary Zone */
251 #define UMA_ZONE_NOBUCKET 0x0400 /* Do not use buckets. */
252 #define UMA_ZONE_MAXBUCKET 0x0800 /* Use largest buckets. */
253 #define UMA_ZONE_CACHESPREAD 0x2000 /*
254 * Spread memory start locations across
255 * all possible cache lines. May
256 * require many virtually contiguous
257 * backend pages and can fail early.
259 #define UMA_ZONE_NODUMP 0x4000 /*
260 * Zone's pages will not be included in
263 #define UMA_ZONE_PCPU 0x8000 /*
264 * Allocates mp_maxid + 1 slabs of
267 #define UMA_ZONE_FIRSTTOUCH 0x10000 /* First touch NUMA policy */
268 #define UMA_ZONE_ROUNDROBIN 0x20000 /* Round-robin NUMA policy. */
269 #define UMA_ZONE_SMR 0x40000 /*
270 * Safe memory reclamation defers
271 * frees until all read sections
272 * have exited. This flag creates
273 * a unique SMR context for this
274 * zone. To share contexts see
275 * uma_zone_set_smr() below.
277 * See sys/smr.h for more details.
279 #define UMA_ZONE_NOKASAN 0x80000 /*
280 * Disable KASAN verification. This is
281 * implied by NOFREE. Cache zones are
282 * not verified by default.
284 /* In use by UMA_ZFLAGs: 0xffe00000 */
287 * These flags are shared between the keg and zone. Some are determined
288 * based on physical parameters of the request and may not be provided by
291 #define UMA_ZONE_INHERIT \
292 (UMA_ZONE_NOTOUCH | UMA_ZONE_MALLOC | UMA_ZONE_NOFREE | \
293 UMA_ZONE_VM | UMA_ZONE_NOTPAGE | UMA_ZONE_PCPU | \
294 UMA_ZONE_FIRSTTOUCH | UMA_ZONE_ROUNDROBIN | UMA_ZONE_NOKASAN)
296 /* Definitions for align */
297 #define UMA_ALIGN_PTR (sizeof(void *) - 1) /* Alignment fit for ptr */
298 #define UMA_ALIGN_LONG (sizeof(long) - 1) /* "" long */
299 #define UMA_ALIGN_INT (sizeof(int) - 1) /* "" int */
300 #define UMA_ALIGN_SHORT (sizeof(short) - 1) /* "" short */
301 #define UMA_ALIGN_CHAR (sizeof(char) - 1) /* "" char */
302 #define UMA_ALIGN_CACHE (0 - 1) /* Cache line size align */
303 #define UMA_ALIGNOF(type) (_Alignof(type) - 1) /* Alignment fit for 'type' */
305 #define UMA_ANYDOMAIN -1 /* Special value for domain search. */
308 * Destroys an empty uma zone. If the zone is not empty uma complains loudly.
311 * zone The zone we want to destroy.
314 void uma_zdestroy(uma_zone_t zone);
317 * Allocates an item out of a zone
320 * zone The zone we are allocating from
321 * arg This data is passed to the ctor function
322 * flags See sys/malloc.h for available flags.
325 * A non-null pointer to an initialized element from the zone is
326 * guaranteed if the wait flag is M_WAITOK. Otherwise a null pointer
327 * may be returned if the zone is empty or the ctor failed.
330 void *uma_zalloc_arg(uma_zone_t zone, void *arg, int flags);
332 /* Allocate per-cpu data. Access the correct data with zpcpu_get(). */
333 void *uma_zalloc_pcpu_arg(uma_zone_t zone, void *arg, int flags);
335 /* Use with SMR zones. */
336 void *uma_zalloc_smr(uma_zone_t zone, int flags);
339 * Allocate an item from a specific NUMA domain. This uses a slow path in
340 * the allocator but is guaranteed to allocate memory from the requested
341 * domain if M_WAITOK is set.
344 * zone The zone we are allocating from
345 * arg This data is passed to the ctor function
346 * domain The domain to allocate from.
347 * flags See sys/malloc.h for available flags.
349 void *uma_zalloc_domain(uma_zone_t zone, void *arg, int domain, int flags);
352 * Allocates an item out of a zone without supplying an argument
354 * This is just a wrapper for uma_zalloc_arg for convenience.
357 static __inline void *uma_zalloc(uma_zone_t zone, int flags);
358 static __inline void *uma_zalloc_pcpu(uma_zone_t zone, int flags);
360 static __inline void *
361 uma_zalloc(uma_zone_t zone, int flags)
363 return uma_zalloc_arg(zone, NULL, flags);
366 static __inline void *
367 uma_zalloc_pcpu(uma_zone_t zone, int flags)
369 return uma_zalloc_pcpu_arg(zone, NULL, flags);
373 * Frees an item back into the specified zone.
376 * zone The zone the item was originally allocated out of.
377 * item The memory to be freed.
378 * arg Argument passed to the destructor
384 void uma_zfree_arg(uma_zone_t zone, void *item, void *arg);
386 /* Use with PCPU zones. */
387 void uma_zfree_pcpu_arg(uma_zone_t zone, void *item, void *arg);
389 /* Use with SMR zones. */
390 void uma_zfree_smr(uma_zone_t zone, void *item);
393 * Frees an item back to a zone without supplying an argument
395 * This is just a wrapper for uma_zfree_arg for convenience.
398 static __inline void uma_zfree(uma_zone_t zone, void *item);
399 static __inline void uma_zfree_pcpu(uma_zone_t zone, void *item);
402 uma_zfree(uma_zone_t zone, void *item)
404 uma_zfree_arg(zone, item, NULL);
408 uma_zfree_pcpu(uma_zone_t zone, void *item)
410 uma_zfree_pcpu_arg(zone, item, NULL);
414 * Wait until the specified zone can allocate an item.
416 void uma_zwait(uma_zone_t zone);
419 * Backend page supplier routines
422 * zone The zone that is requesting pages.
423 * size The number of bytes being requested.
424 * pflag Flags for these memory pages, see below.
425 * domain The NUMA domain that we prefer for this allocation.
426 * wait Indicates our willingness to block.
429 * A pointer to the allocated memory or NULL on failure.
432 typedef void *(*uma_alloc)(uma_zone_t zone, vm_size_t size, int domain,
433 uint8_t *pflag, int wait);
436 * Backend page free routines
439 * item A pointer to the previously allocated pages.
440 * size The original size of the allocation.
441 * pflag The flags for the slab. See UMA_SLAB_* below.
446 typedef void (*uma_free)(void *item, vm_size_t size, uint8_t pflag);
449 * Reclaims unused memory
452 * req Reclamation request type.
456 #define UMA_RECLAIM_DRAIN 1 /* release bucket cache */
457 #define UMA_RECLAIM_DRAIN_CPU 2 /* release bucket and per-CPU caches */
458 #define UMA_RECLAIM_TRIM 3 /* trim bucket cache to WSS */
459 void uma_reclaim(int req);
460 void uma_zone_reclaim(uma_zone_t, int req);
463 * Sets the alignment mask to be used for all zones requesting cache
464 * alignment. Should be called by MD boot code prior to starting VM/UMA.
467 * align The alignment mask
472 void uma_set_align(int align);
475 * Set a reserved number of items to hold for M_USE_RESERVE allocations. All
476 * other requests must allocate new backing pages.
478 void uma_zone_reserve(uma_zone_t zone, int nitems);
481 * Reserves the maximum KVA space required by the zone and configures the zone
482 * to use a VM_ALLOC_NOOBJ-based backend allocator.
485 * zone The zone to update.
486 * nitems The upper limit on the number of items that can be allocated.
489 * 0 if KVA space can not be allocated
493 * When the machine supports a direct map and the zone's items are smaller
494 * than a page, the zone will use the direct map instead of allocating KVA
497 int uma_zone_reserve_kva(uma_zone_t zone, int nitems);
500 * Sets an upper limit on the number of items allocated from a zone
503 * zone The zone to limit
504 * nitems The requested upper limit on the number of items allowed
507 * int The effective value of nitems
509 int uma_zone_set_max(uma_zone_t zone, int nitems);
512 * Sets an upper limit on the number of items allowed in zone's caches
515 * zone The zone to limit
516 * nitems The requested upper limit on the number of items allowed
518 void uma_zone_set_maxcache(uma_zone_t zone, int nitems);
521 * Obtains the effective limit on the number of items in a zone
524 * zone The zone to obtain the effective limit from
528 * int The effective limit of the zone
530 int uma_zone_get_max(uma_zone_t zone);
533 * Sets a warning to be printed when limit is reached
536 * zone The zone we will warn about
537 * warning Warning content
542 void uma_zone_set_warning(uma_zone_t zone, const char *warning);
545 * Sets a function to run when limit is reached
548 * zone The zone to which this applies
549 * fx The function ro run
554 typedef void (*uma_maxaction_t)(uma_zone_t, int);
555 void uma_zone_set_maxaction(uma_zone_t zone, uma_maxaction_t);
558 * Obtains the approximate current number of items allocated from a zone
561 * zone The zone to obtain the current allocation count from
564 * int The approximate current number of items allocated from the zone
566 int uma_zone_get_cur(uma_zone_t zone);
569 * The following two routines (uma_zone_set_init/fini)
570 * are used to set the backend init/fini pair which acts on an
571 * object as it becomes allocated and is placed in a slab within
572 * the specified zone's backing keg. These should probably not
573 * be changed once allocations have already begun, but only be set
574 * immediately upon zone creation.
576 void uma_zone_set_init(uma_zone_t zone, uma_init uminit);
577 void uma_zone_set_fini(uma_zone_t zone, uma_fini fini);
580 * The following two routines (uma_zone_set_zinit/zfini) are
581 * used to set the zinit/zfini pair which acts on an object as
582 * it passes from the backing Keg's slab cache to the
583 * specified Zone's bucket cache. These should probably not
584 * be changed once allocations have already begun, but only be set
585 * immediately upon zone creation.
587 void uma_zone_set_zinit(uma_zone_t zone, uma_init zinit);
588 void uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini);
591 * Replaces the standard backend allocator for this zone.
594 * zone The zone whose backend allocator is being changed.
595 * allocf A pointer to the allocation function
601 * This could be used to implement pageable allocation, or perhaps
602 * even DMA allocators if used in conjunction with the OFFPAGE
606 void uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf);
609 * Used for freeing memory provided by the allocf above
612 * zone The zone that intends to use this free routine.
613 * freef The page freeing routine.
619 void uma_zone_set_freef(uma_zone_t zone, uma_free freef);
622 * Associate a zone with a smr context that is allocated after creation
623 * so that multiple zones may share the same context.
625 void uma_zone_set_smr(uma_zone_t zone, smr_t smr);
628 * Fetch the smr context that was set or made in uma_zcreate().
630 smr_t uma_zone_get_smr(uma_zone_t zone);
633 * These flags are setable in the allocf and visible in the freef.
635 #define UMA_SLAB_BOOT 0x01 /* Slab alloced from boot pages */
636 #define UMA_SLAB_KERNEL 0x04 /* Slab alloced from kmem */
637 #define UMA_SLAB_PRIV 0x08 /* Slab alloced from priv allocator */
638 /* 0x02, 0x10, 0x40, and 0x80 are available */
641 * Used to pre-fill a zone with some number of items
644 * zone The zone to fill
645 * itemcnt The number of items to reserve
650 * NOTE: This is blocking and should only be done at startup
652 void uma_prealloc(uma_zone_t zone, int itemcnt);
655 * Used to determine if a fixed-size zone is exhausted.
658 * zone The zone to check
661 * Non-zero if zone is exhausted.
663 int uma_zone_exhausted(uma_zone_t zone);
666 * Returns the bytes of memory consumed by the zone.
668 size_t uma_zone_memory(uma_zone_t zone);
671 * Common UMA_ZONE_PCPU zones.
673 extern uma_zone_t pcpu_zone_4;
674 extern uma_zone_t pcpu_zone_8;
675 extern uma_zone_t pcpu_zone_16;
676 extern uma_zone_t pcpu_zone_32;
677 extern uma_zone_t pcpu_zone_64;
680 * Exported statistics structures to be used by user space monitoring tools.
681 * Statistics stream consists of a uma_stream_header, followed by a series of
682 * alternative uma_type_header and uma_type_stat structures.
684 #define UMA_STREAM_VERSION 0x00000001
685 struct uma_stream_header {
686 uint32_t ush_version; /* Stream format version. */
687 uint32_t ush_maxcpus; /* Value of MAXCPU for stream. */
688 uint32_t ush_count; /* Number of records. */
689 uint32_t _ush_pad; /* Pad/reserved field. */
692 #define UTH_MAX_NAME 32
693 #define UTH_ZONE_SECONDARY 0x00000001
694 struct uma_type_header {
696 * Static per-zone data, some extracted from the supporting keg.
698 char uth_name[UTH_MAX_NAME];
699 uint32_t uth_align; /* Keg: alignment. */
700 uint32_t uth_size; /* Keg: requested size of item. */
701 uint32_t uth_rsize; /* Keg: real size of item. */
702 uint32_t uth_maxpages; /* Keg: maximum number of pages. */
703 uint32_t uth_limit; /* Keg: max items to allocate. */
706 * Current dynamic zone/keg-derived statistics.
708 uint32_t uth_pages; /* Keg: pages allocated. */
709 uint32_t uth_keg_free; /* Keg: items free. */
710 uint32_t uth_zone_free; /* Zone: items free. */
711 uint32_t uth_bucketsize; /* Zone: desired bucket size. */
712 uint32_t uth_zone_flags; /* Zone: flags. */
713 uint64_t uth_allocs; /* Zone: number of allocations. */
714 uint64_t uth_frees; /* Zone: number of frees. */
715 uint64_t uth_fails; /* Zone: number of alloc failures. */
716 uint64_t uth_sleeps; /* Zone: number of alloc sleeps. */
717 uint64_t uth_xdomain; /* Zone: Number of cross domain frees. */
718 uint64_t _uth_reserved1[1]; /* Reserved. */
721 struct uma_percpu_stat {
722 uint64_t ups_allocs; /* Cache: number of allocations. */
723 uint64_t ups_frees; /* Cache: number of frees. */
724 uint64_t ups_cache_free; /* Cache: free items in cache. */
725 uint64_t _ups_reserved[5]; /* Reserved. */
728 void uma_reclaim_wakeup(void);
729 void uma_reclaim_worker(void *);
731 unsigned long uma_limit(void);
733 /* Return the amount of memory managed by UMA. */
734 unsigned long uma_size(void);
736 /* Return the amount of memory remaining. May be negative. */
737 long uma_avail(void);
739 #endif /* _VM_UMA_H_ */