xref: /freebsd/sys/vm/uma.h (revision a0409676120c1e558d0ade943019934e0f15118d)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2002, 2003, 2004, 2005 Jeffrey Roberson <jeff@FreeBSD.org>
5  * Copyright (c) 2004, 2005 Bosko Milekic <bmilekic@FreeBSD.org>
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice unmodified, this list of conditions, and the following
13  *    disclaimer.
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.
17  *
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,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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.
28  *
29  * $FreeBSD$
30  *
31  */
32 
33 /*
34  * uma.h - External definitions for the Universal Memory Allocator
35  *
36 */
37 
38 #ifndef _VM_UMA_H_
39 #define _VM_UMA_H_
40 
41 #include <sys/param.h>		/* For NULL */
42 #include <sys/malloc.h>		/* For M_* */
43 #include <sys/_smr.h>
44 
45 /* User visible parameters */
46 #define	UMA_SMALLEST_UNIT	8 /* Smallest item allocated */
47 
48 /* Types and type defs */
49 
50 struct uma_zone;
51 /* Opaque type used as a handle to the zone */
52 typedef struct uma_zone * uma_zone_t;
53 
54 /*
55  * Item constructor
56  *
57  * Arguments:
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
62  *
63  * Returns:
64  *	0      on success
65  *      errno  on failure
66  *
67  * Discussion:
68  *	The constructor is called just before the memory is returned
69  *	to the user. It may block if necessary.
70  */
71 typedef int (*uma_ctor)(void *mem, int size, void *arg, int flags);
72 
73 /*
74  * Item destructor
75  *
76  * Arguments:
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
80  *
81  * Returns:
82  *	Nothing
83  *
84  * Discussion:
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.
88  */
89 typedef void (*uma_dtor)(void *mem, int size, void *arg);
90 
91 /*
92  * Item initializer
93  *
94  * Arguments:
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
98  *
99  * Returns:
100  *	0      on success
101  *      errno  on failure
102  *
103  * Discussion:
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
106  *	state.
107  */
108 typedef int (*uma_init)(void *mem, int size, int flags);
109 
110 /*
111  * Item discard function
112  *
113  * Arguments:
114  *	item  A pointer to memory which has been 'freed' but has not left the
115  *	      zone's cache.
116  *	size  The size of the item being discarded.
117  *
118  * Returns:
119  *	Nothing
120  *
121  * Discussion:
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.
124  */
125 typedef void (*uma_fini)(void *mem, int size);
126 
127 /*
128  * Import new memory into a cache zone.
129  */
130 typedef int (*uma_import)(void *arg, void **store, int count, int domain,
131     int flags);
132 
133 /*
134  * Free memory from a cache zone.
135  */
136 typedef void (*uma_release)(void *arg, void **store, int count);
137 
138 /*
139  * What's the difference between initializing and constructing?
140  *
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.
146  *
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
150  * re-initialize it.
151  *
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.
154  *
155  */
156 
157 /* Function proto types */
158 
159 /*
160  * Create a new uma zone
161  *
162  * Arguments:
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
172  *		eg 4 would be 0x3
173  *	flags A set of parameters that control the behavior of the zone.
174  *
175  * Returns:
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.
178  */
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);
182 
183 /*
184  * Create a secondary uma zone
185  *
186  * Arguments:
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.
195  *
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).
206  *
207  *	primary A reference to this zone's Primary Zone which contains the
208  *		backing Keg for the Secondary Zone being added.
209  *
210  * Returns:
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.
213  */
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);
216 
217 /*
218  * Create cache-only zones.
219  *
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
224  * specific.
225  */
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);
229 
230 /*
231  * Definitions for uma_zcreate flags
232  *
233  * These flags share space with UMA_ZFLAGs in uma_int.h.  Be careful not to
234  * overlap when adding new features.
235  */
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.
240 					 */
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
247 					 * only.
248 					 */
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.
258 					 */
259 #define	UMA_ZONE_NODUMP		0x4000	/*
260 					 * Zone's pages will not be included in
261 					 * mini-dumps.
262 					 */
263 #define	UMA_ZONE_PCPU		0x8000	/*
264 					 * Allocates mp_maxid + 1 slabs of
265 					 * PAGE_SIZE
266 					 */
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.
276 					 *
277 					 * See sys/smr.h for more details.
278 					 */
279 /* In use by UMA_ZFLAGs:	0xffe00000 */
280 
281 /*
282  * These flags are shared between the keg and zone.  Some are determined
283  * based on physical parameters of the request and may not be provided by
284  * the consumer.
285  */
286 #define	UMA_ZONE_INHERIT						\
287     (UMA_ZONE_NOTOUCH | UMA_ZONE_MALLOC | UMA_ZONE_NOFREE |		\
288      UMA_ZONE_VM | UMA_ZONE_NOTPAGE | UMA_ZONE_PCPU |			\
289      UMA_ZONE_FIRSTTOUCH | UMA_ZONE_ROUNDROBIN)
290 
291 /* Definitions for align */
292 #define UMA_ALIGN_PTR	(sizeof(void *) - 1)	/* Alignment fit for ptr */
293 #define UMA_ALIGN_LONG	(sizeof(long) - 1)	/* "" long */
294 #define UMA_ALIGN_INT	(sizeof(int) - 1)	/* "" int */
295 #define UMA_ALIGN_SHORT	(sizeof(short) - 1)	/* "" short */
296 #define UMA_ALIGN_CHAR	(sizeof(char) - 1)	/* "" char */
297 #define UMA_ALIGN_CACHE	(0 - 1)			/* Cache line size align */
298 #define	UMA_ALIGNOF(type) (_Alignof(type) - 1)	/* Alignment fit for 'type' */
299 
300 #define	UMA_ANYDOMAIN	-1	/* Special value for domain search. */
301 
302 /*
303  * Destroys an empty uma zone.  If the zone is not empty uma complains loudly.
304  *
305  * Arguments:
306  *	zone  The zone we want to destroy.
307  *
308  */
309 void uma_zdestroy(uma_zone_t zone);
310 
311 /*
312  * Allocates an item out of a zone
313  *
314  * Arguments:
315  *	zone  The zone we are allocating from
316  *	arg   This data is passed to the ctor function
317  *	flags See sys/malloc.h for available flags.
318  *
319  * Returns:
320  *	A non-null pointer to an initialized element from the zone is
321  *	guaranteed if the wait flag is M_WAITOK.  Otherwise a null pointer
322  *	may be returned if the zone is empty or the ctor failed.
323  */
324 
325 void *uma_zalloc_arg(uma_zone_t zone, void *arg, int flags);
326 
327 /* Allocate per-cpu data.  Access the correct data with zpcpu_get(). */
328 void *uma_zalloc_pcpu_arg(uma_zone_t zone, void *arg, int flags);
329 
330 /* Use with SMR zones. */
331 void *uma_zalloc_smr(uma_zone_t zone, int flags);
332 
333 /*
334  * Allocate an item from a specific NUMA domain.  This uses a slow path in
335  * the allocator but is guaranteed to allocate memory from the requested
336  * domain if M_WAITOK is set.
337  *
338  * Arguments:
339  *	zone  The zone we are allocating from
340  *	arg   This data is passed to the ctor function
341  *	domain The domain to allocate from.
342  *	flags See sys/malloc.h for available flags.
343  */
344 void *uma_zalloc_domain(uma_zone_t zone, void *arg, int domain, int flags);
345 
346 /*
347  * Allocates an item out of a zone without supplying an argument
348  *
349  * This is just a wrapper for uma_zalloc_arg for convenience.
350  *
351  */
352 static __inline void *uma_zalloc(uma_zone_t zone, int flags);
353 static __inline void *uma_zalloc_pcpu(uma_zone_t zone, int flags);
354 
355 static __inline void *
356 uma_zalloc(uma_zone_t zone, int flags)
357 {
358 	return uma_zalloc_arg(zone, NULL, flags);
359 }
360 
361 static __inline void *
362 uma_zalloc_pcpu(uma_zone_t zone, int flags)
363 {
364 	return uma_zalloc_pcpu_arg(zone, NULL, flags);
365 }
366 
367 /*
368  * Frees an item back into the specified zone.
369  *
370  * Arguments:
371  *	zone  The zone the item was originally allocated out of.
372  *	item  The memory to be freed.
373  *	arg   Argument passed to the destructor
374  *
375  * Returns:
376  *	Nothing.
377  */
378 
379 void uma_zfree_arg(uma_zone_t zone, void *item, void *arg);
380 
381 /* Use with PCPU zones. */
382 void uma_zfree_pcpu_arg(uma_zone_t zone, void *item, void *arg);
383 
384 /* Use with SMR zones. */
385 void uma_zfree_smr(uma_zone_t zone, void *item);
386 
387 /*
388  * Frees an item back to a zone without supplying an argument
389  *
390  * This is just a wrapper for uma_zfree_arg for convenience.
391  *
392  */
393 static __inline void uma_zfree(uma_zone_t zone, void *item);
394 static __inline void uma_zfree_pcpu(uma_zone_t zone, void *item);
395 
396 static __inline void
397 uma_zfree(uma_zone_t zone, void *item)
398 {
399 	uma_zfree_arg(zone, item, NULL);
400 }
401 
402 static __inline void
403 uma_zfree_pcpu(uma_zone_t zone, void *item)
404 {
405 	uma_zfree_pcpu_arg(zone, item, NULL);
406 }
407 
408 /*
409  * Wait until the specified zone can allocate an item.
410  */
411 void uma_zwait(uma_zone_t zone);
412 
413 /*
414  * Backend page supplier routines
415  *
416  * Arguments:
417  *	zone  The zone that is requesting pages.
418  *	size  The number of bytes being requested.
419  *	pflag Flags for these memory pages, see below.
420  *	domain The NUMA domain that we prefer for this allocation.
421  *	wait  Indicates our willingness to block.
422  *
423  * Returns:
424  *	A pointer to the allocated memory or NULL on failure.
425  */
426 
427 typedef void *(*uma_alloc)(uma_zone_t zone, vm_size_t size, int domain,
428     uint8_t *pflag, int wait);
429 
430 /*
431  * Backend page free routines
432  *
433  * Arguments:
434  *	item  A pointer to the previously allocated pages.
435  *	size  The original size of the allocation.
436  *	pflag The flags for the slab.  See UMA_SLAB_* below.
437  *
438  * Returns:
439  *	None
440  */
441 typedef void (*uma_free)(void *item, vm_size_t size, uint8_t pflag);
442 
443 /*
444  * Reclaims unused memory
445  *
446  * Arguments:
447  *	req  Reclamation request type.
448  * Returns:
449  *	None
450  */
451 #define	UMA_RECLAIM_DRAIN	1	/* release bucket cache */
452 #define	UMA_RECLAIM_DRAIN_CPU	2	/* release bucket and per-CPU caches */
453 #define	UMA_RECLAIM_TRIM	3	/* trim bucket cache to WSS */
454 void uma_reclaim(int req);
455 void uma_zone_reclaim(uma_zone_t, int req);
456 
457 /*
458  * Sets the alignment mask to be used for all zones requesting cache
459  * alignment.  Should be called by MD boot code prior to starting VM/UMA.
460  *
461  * Arguments:
462  *	align The alignment mask
463  *
464  * Returns:
465  *	Nothing
466  */
467 void uma_set_align(int align);
468 
469 /*
470  * Set a reserved number of items to hold for M_USE_RESERVE allocations.  All
471  * other requests must allocate new backing pages.
472  */
473 void uma_zone_reserve(uma_zone_t zone, int nitems);
474 
475 /*
476  * Reserves the maximum KVA space required by the zone and configures the zone
477  * to use a VM_ALLOC_NOOBJ-based backend allocator.
478  *
479  * Arguments:
480  *	zone  The zone to update.
481  *	nitems  The upper limit on the number of items that can be allocated.
482  *
483  * Returns:
484  *	0  if KVA space can not be allocated
485  *	1  if successful
486  *
487  * Discussion:
488  *	When the machine supports a direct map and the zone's items are smaller
489  *	than a page, the zone will use the direct map instead of allocating KVA
490  *	space.
491  */
492 int uma_zone_reserve_kva(uma_zone_t zone, int nitems);
493 
494 /*
495  * Sets an upper limit on the number of items allocated from a zone
496  *
497  * Arguments:
498  *	zone  The zone to limit
499  *	nitems  The requested upper limit on the number of items allowed
500  *
501  * Returns:
502  *	int  The effective value of nitems
503  */
504 int uma_zone_set_max(uma_zone_t zone, int nitems);
505 
506 /*
507  * Sets an upper limit on the number of items allowed in zone's caches
508  *
509  * Arguments:
510  *      zone  The zone to limit
511  *      nitems  The requested upper limit on the number of items allowed
512  */
513 void uma_zone_set_maxcache(uma_zone_t zone, int nitems);
514 
515 /*
516  * Obtains the effective limit on the number of items in a zone
517  *
518  * Arguments:
519  *	zone  The zone to obtain the effective limit from
520  *
521  * Return:
522  *	0  No limit
523  *	int  The effective limit of the zone
524  */
525 int uma_zone_get_max(uma_zone_t zone);
526 
527 /*
528  * Sets a warning to be printed when limit is reached
529  *
530  * Arguments:
531  *	zone  The zone we will warn about
532  *	warning  Warning content
533  *
534  * Returns:
535  *	Nothing
536  */
537 void uma_zone_set_warning(uma_zone_t zone, const char *warning);
538 
539 /*
540  * Sets a function to run when limit is reached
541  *
542  * Arguments:
543  *	zone  The zone to which this applies
544  *	fx  The function ro run
545  *
546  * Returns:
547  *	Nothing
548  */
549 typedef void (*uma_maxaction_t)(uma_zone_t, int);
550 void uma_zone_set_maxaction(uma_zone_t zone, uma_maxaction_t);
551 
552 /*
553  * Obtains the approximate current number of items allocated from a zone
554  *
555  * Arguments:
556  *	zone  The zone to obtain the current allocation count from
557  *
558  * Return:
559  *	int  The approximate current number of items allocated from the zone
560  */
561 int uma_zone_get_cur(uma_zone_t zone);
562 
563 /*
564  * The following two routines (uma_zone_set_init/fini)
565  * are used to set the backend init/fini pair which acts on an
566  * object as it becomes allocated and is placed in a slab within
567  * the specified zone's backing keg.  These should probably not
568  * be changed once allocations have already begun, but only be set
569  * immediately upon zone creation.
570  */
571 void uma_zone_set_init(uma_zone_t zone, uma_init uminit);
572 void uma_zone_set_fini(uma_zone_t zone, uma_fini fini);
573 
574 /*
575  * The following two routines (uma_zone_set_zinit/zfini) are
576  * used to set the zinit/zfini pair which acts on an object as
577  * it passes from the backing Keg's slab cache to the
578  * specified Zone's bucket cache.  These should probably not
579  * be changed once allocations have already begun, but only be set
580  * immediately upon zone creation.
581  */
582 void uma_zone_set_zinit(uma_zone_t zone, uma_init zinit);
583 void uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini);
584 
585 /*
586  * Replaces the standard backend allocator for this zone.
587  *
588  * Arguments:
589  *	zone   The zone whose backend allocator is being changed.
590  *	allocf A pointer to the allocation function
591  *
592  * Returns:
593  *	Nothing
594  *
595  * Discussion:
596  *	This could be used to implement pageable allocation, or perhaps
597  *	even DMA allocators if used in conjunction with the OFFPAGE
598  *	zone flag.
599  */
600 
601 void uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf);
602 
603 /*
604  * Used for freeing memory provided by the allocf above
605  *
606  * Arguments:
607  *	zone  The zone that intends to use this free routine.
608  *	freef The page freeing routine.
609  *
610  * Returns:
611  *	Nothing
612  */
613 
614 void uma_zone_set_freef(uma_zone_t zone, uma_free freef);
615 
616 /*
617  * Associate a zone with a smr context that is allocated after creation
618  * so that multiple zones may share the same context.
619  */
620 void uma_zone_set_smr(uma_zone_t zone, smr_t smr);
621 
622 /*
623  * Fetch the smr context that was set or made in uma_zcreate().
624  */
625 smr_t uma_zone_get_smr(uma_zone_t zone);
626 
627 /*
628  * These flags are setable in the allocf and visible in the freef.
629  */
630 #define UMA_SLAB_BOOT	0x01		/* Slab alloced from boot pages */
631 #define UMA_SLAB_KERNEL	0x04		/* Slab alloced from kmem */
632 #define UMA_SLAB_PRIV	0x08		/* Slab alloced from priv allocator */
633 /* 0x02, 0x10, 0x40, and 0x80 are available */
634 
635 /*
636  * Used to pre-fill a zone with some number of items
637  *
638  * Arguments:
639  *	zone    The zone to fill
640  *	itemcnt The number of items to reserve
641  *
642  * Returns:
643  *	Nothing
644  *
645  * NOTE: This is blocking and should only be done at startup
646  */
647 void uma_prealloc(uma_zone_t zone, int itemcnt);
648 
649 /*
650  * Used to determine if a fixed-size zone is exhausted.
651  *
652  * Arguments:
653  *	zone    The zone to check
654  *
655  * Returns:
656  *	Non-zero if zone is exhausted.
657  */
658 int uma_zone_exhausted(uma_zone_t zone);
659 
660 /*
661  * Returns the bytes of memory consumed by the zone.
662  */
663 size_t uma_zone_memory(uma_zone_t zone);
664 
665 /*
666  * Common UMA_ZONE_PCPU zones.
667  */
668 extern uma_zone_t pcpu_zone_4;
669 extern uma_zone_t pcpu_zone_8;
670 extern uma_zone_t pcpu_zone_16;
671 extern uma_zone_t pcpu_zone_32;
672 extern uma_zone_t pcpu_zone_64;
673 
674 /*
675  * Exported statistics structures to be used by user space monitoring tools.
676  * Statistics stream consists of a uma_stream_header, followed by a series of
677  * alternative uma_type_header and uma_type_stat structures.
678  */
679 #define	UMA_STREAM_VERSION	0x00000001
680 struct uma_stream_header {
681 	uint32_t	ush_version;	/* Stream format version. */
682 	uint32_t	ush_maxcpus;	/* Value of MAXCPU for stream. */
683 	uint32_t	ush_count;	/* Number of records. */
684 	uint32_t	_ush_pad;	/* Pad/reserved field. */
685 };
686 
687 #define	UTH_MAX_NAME	32
688 #define	UTH_ZONE_SECONDARY	0x00000001
689 struct uma_type_header {
690 	/*
691 	 * Static per-zone data, some extracted from the supporting keg.
692 	 */
693 	char		uth_name[UTH_MAX_NAME];
694 	uint32_t	uth_align;	/* Keg: alignment. */
695 	uint32_t	uth_size;	/* Keg: requested size of item. */
696 	uint32_t	uth_rsize;	/* Keg: real size of item. */
697 	uint32_t	uth_maxpages;	/* Keg: maximum number of pages. */
698 	uint32_t	uth_limit;	/* Keg: max items to allocate. */
699 
700 	/*
701 	 * Current dynamic zone/keg-derived statistics.
702 	 */
703 	uint32_t	uth_pages;	/* Keg: pages allocated. */
704 	uint32_t	uth_keg_free;	/* Keg: items free. */
705 	uint32_t	uth_zone_free;	/* Zone: items free. */
706 	uint32_t	uth_bucketsize;	/* Zone: desired bucket size. */
707 	uint32_t	uth_zone_flags;	/* Zone: flags. */
708 	uint64_t	uth_allocs;	/* Zone: number of allocations. */
709 	uint64_t	uth_frees;	/* Zone: number of frees. */
710 	uint64_t	uth_fails;	/* Zone: number of alloc failures. */
711 	uint64_t	uth_sleeps;	/* Zone: number of alloc sleeps. */
712 	uint64_t	uth_xdomain;	/* Zone: Number of cross domain frees. */
713 	uint64_t	_uth_reserved1[1];	/* Reserved. */
714 };
715 
716 struct uma_percpu_stat {
717 	uint64_t	ups_allocs;	/* Cache: number of allocations. */
718 	uint64_t	ups_frees;	/* Cache: number of frees. */
719 	uint64_t	ups_cache_free;	/* Cache: free items in cache. */
720 	uint64_t	_ups_reserved[5];	/* Reserved. */
721 };
722 
723 void uma_reclaim_wakeup(void);
724 void uma_reclaim_worker(void *);
725 
726 unsigned long uma_limit(void);
727 
728 /* Return the amount of memory managed by UMA. */
729 unsigned long uma_size(void);
730 
731 /* Return the amount of memory remaining.  May be negative. */
732 long uma_avail(void);
733 
734 #endif	/* _VM_UMA_H_ */
735