xref: /freebsd/sys/vm/uma.h (revision 480093f4440d54b30b3025afeac24b48f2ba7a2e)
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 
44 /* User visible parameters */
45 #define	UMA_SMALLEST_UNIT	8 /* Smallest item allocated */
46 
47 /* Types and type defs */
48 
49 struct uma_zone;
50 /* Opaque type used as a handle to the zone */
51 typedef struct uma_zone * uma_zone_t;
52 
53 /*
54  * Item constructor
55  *
56  * Arguments:
57  *	item  A pointer to the memory which has been allocated.
58  *	arg   The arg field passed to uma_zalloc_arg
59  *	size  The size of the allocated item
60  *	flags See zalloc flags
61  *
62  * Returns:
63  *	0      on success
64  *      errno  on failure
65  *
66  * Discussion:
67  *	The constructor is called just before the memory is returned
68  *	to the user. It may block if necessary.
69  */
70 typedef int (*uma_ctor)(void *mem, int size, void *arg, int flags);
71 
72 /*
73  * Item destructor
74  *
75  * Arguments:
76  *	item  A pointer to the memory which has been allocated.
77  *	size  The size of the item being destructed.
78  *	arg   Argument passed through uma_zfree_arg
79  *
80  * Returns:
81  *	Nothing
82  *
83  * Discussion:
84  *	The destructor may perform operations that differ from those performed
85  *	by the initializer, but it must leave the object in the same state.
86  *	This IS type stable storage.  This is called after EVERY zfree call.
87  */
88 typedef void (*uma_dtor)(void *mem, int size, void *arg);
89 
90 /*
91  * Item initializer
92  *
93  * Arguments:
94  *	item  A pointer to the memory which has been allocated.
95  *	size  The size of the item being initialized.
96  *	flags See zalloc flags
97  *
98  * Returns:
99  *	0      on success
100  *      errno  on failure
101  *
102  * Discussion:
103  *	The initializer is called when the memory is cached in the uma zone.
104  *	The initializer and the destructor should leave the object in the same
105  *	state.
106  */
107 typedef int (*uma_init)(void *mem, int size, int flags);
108 
109 /*
110  * Item discard function
111  *
112  * Arguments:
113  *	item  A pointer to memory which has been 'freed' but has not left the
114  *	      zone's cache.
115  *	size  The size of the item being discarded.
116  *
117  * Returns:
118  *	Nothing
119  *
120  * Discussion:
121  *	This routine is called when memory leaves a zone and is returned to the
122  *	system for other uses.  It is the counter-part to the init function.
123  */
124 typedef void (*uma_fini)(void *mem, int size);
125 
126 /*
127  * Import new memory into a cache zone.
128  */
129 typedef int (*uma_import)(void *arg, void **store, int count, int domain,
130     int flags);
131 
132 /*
133  * Free memory from a cache zone.
134  */
135 typedef void (*uma_release)(void *arg, void **store, int count);
136 
137 /*
138  * What's the difference between initializing and constructing?
139  *
140  * The item is initialized when it is cached, and this is the state that the
141  * object should be in when returned to the allocator. The purpose of this is
142  * to remove some code which would otherwise be called on each allocation by
143  * utilizing a known, stable state.  This differs from the constructor which
144  * will be called on EVERY allocation.
145  *
146  * For example, in the initializer you may want to initialize embedded locks,
147  * NULL list pointers, set up initial states, magic numbers, etc.  This way if
148  * the object is held in the allocator and re-used it won't be necessary to
149  * re-initialize it.
150  *
151  * The constructor may be used to lock a data structure, link it on to lists,
152  * bump reference counts or total counts of outstanding structures, etc.
153  *
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 master 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 master zone) with
205  *		uma_zone_set_zinit/zfini() (note subtle 'z' prefix).
206  *
207  *	master  A reference to this zone's Master Zone (Primary Zone),
208  *		which contains the backing Keg for the Secondary Zone
209  *		being added.
210  *
211  * Returns:
212  *	A pointer to a structure which is intended to be opaque to users of
213  *	the interface.  The value may be null if the wait flag is not set.
214  */
215 uma_zone_t uma_zsecond_create(char *name, uma_ctor ctor, uma_dtor dtor,
216 		    uma_init zinit, uma_fini zfini, uma_zone_t master);
217 
218 /*
219  * Create cache-only zones.
220  *
221  * This allows uma's per-cpu cache facilities to handle arbitrary
222  * pointers.  Consumers must specify the import and release functions to
223  * fill and destroy caches.  UMA does not allocate any memory for these
224  * zones.  The 'arg' parameter is passed to import/release and is caller
225  * specific.
226  */
227 uma_zone_t uma_zcache_create(char *name, int size, uma_ctor ctor, uma_dtor dtor,
228 		    uma_init zinit, uma_fini zfini, uma_import zimport,
229 		    uma_release zrelease, void *arg, int flags);
230 
231 /*
232  * Definitions for uma_zcreate flags
233  *
234  * These flags share space with UMA_ZFLAGs in uma_int.h.  Be careful not to
235  * overlap when adding new features.
236  */
237 #define UMA_ZONE_ZINIT		0x0002	/* Initialize with zeros */
238 #define UMA_ZONE_NOTOUCH	0x0008	/* UMA may not access the memory */
239 #define UMA_ZONE_MALLOC		0x0010	/* For use by malloc(9) only! */
240 #define UMA_ZONE_NOFREE		0x0020	/* Do not free slabs of this type! */
241 #define UMA_ZONE_MTXCLASS	0x0040	/* Create a new lock class */
242 #define	UMA_ZONE_VM		0x0080	/*
243 					 * Used for internal vm datastructures
244 					 * only.
245 					 */
246 #define	UMA_ZONE_NOTPAGE	0x0100	/* allocf memory not vm pages */
247 #define	UMA_ZONE_SECONDARY	0x0200	/* Zone is a Secondary Zone */
248 #define	UMA_ZONE_NOBUCKET	0x0400	/* Do not use buckets. */
249 #define	UMA_ZONE_MAXBUCKET	0x0800	/* Use largest buckets. */
250 #define	UMA_ZONE_MINBUCKET	0x1000	/* Use smallest buckets. */
251 #define	UMA_ZONE_CACHESPREAD	0x2000	/*
252 					 * Spread memory start locations across
253 					 * all possible cache lines.  May
254 					 * require many virtually contiguous
255 					 * backend pages and can fail early.
256 					 */
257 #define	UMA_ZONE_NODUMP		0x4000	/*
258 					 * Zone's pages will not be included in
259 					 * mini-dumps.
260 					 */
261 #define	UMA_ZONE_PCPU		0x8000	/*
262 					 * Allocates mp_maxid + 1 slabs of PAGE_SIZE
263 					 */
264 #define	UMA_ZONE_FIRSTTOUCH	0x10000	/* First touch NUMA policy */
265 #define	UMA_ZONE_ROUNDROBIN	0x20000	/* Round-robin NUMA policy. */
266 /* In use by UMA_ZFLAGs:	0xffe00000 */
267 
268 /*
269  * These flags are shared between the keg and zone.  In zones wishing to add
270  * new kegs these flags must be compatible.  Some are determined based on
271  * physical parameters of the request and may not be provided by the consumer.
272  */
273 #define	UMA_ZONE_INHERIT						\
274     (UMA_ZONE_NOTOUCH | UMA_ZONE_MALLOC | UMA_ZONE_NOFREE |		\
275      UMA_ZONE_NOTPAGE | UMA_ZONE_PCPU | UMA_ZONE_FIRSTTOUCH |		\
276      UMA_ZONE_ROUNDROBIN)
277 
278 /* Definitions for align */
279 #define UMA_ALIGN_PTR	(sizeof(void *) - 1)	/* Alignment fit for ptr */
280 #define UMA_ALIGN_LONG	(sizeof(long) - 1)	/* "" long */
281 #define UMA_ALIGN_INT	(sizeof(int) - 1)	/* "" int */
282 #define UMA_ALIGN_SHORT	(sizeof(short) - 1)	/* "" short */
283 #define UMA_ALIGN_CHAR	(sizeof(char) - 1)	/* "" char */
284 #define UMA_ALIGN_CACHE	(0 - 1)			/* Cache line size align */
285 #define	UMA_ALIGNOF(type) (_Alignof(type) - 1)	/* Alignment fit for 'type' */
286 
287 #define	UMA_ANYDOMAIN	-1	/* Special value for domain search. */
288 
289 /*
290  * Destroys an empty uma zone.  If the zone is not empty uma complains loudly.
291  *
292  * Arguments:
293  *	zone  The zone we want to destroy.
294  *
295  */
296 void uma_zdestroy(uma_zone_t zone);
297 
298 /*
299  * Allocates an item out of a zone
300  *
301  * Arguments:
302  *	zone  The zone we are allocating from
303  *	arg   This data is passed to the ctor function
304  *	flags See sys/malloc.h for available flags.
305  *
306  * Returns:
307  *	A non-null pointer to an initialized element from the zone is
308  *	guaranteed if the wait flag is M_WAITOK.  Otherwise a null pointer
309  *	may be returned if the zone is empty or the ctor failed.
310  */
311 
312 void *uma_zalloc_arg(uma_zone_t zone, void *arg, int flags);
313 void *uma_zalloc_pcpu_arg(uma_zone_t zone, void *arg, int flags);
314 
315 /*
316  * Allocate an item from a specific NUMA domain.  This uses a slow path in
317  * the allocator but is guaranteed to allocate memory from the requested
318  * domain if M_WAITOK is set.
319  *
320  * Arguments:
321  *	zone  The zone we are allocating from
322  *	arg   This data is passed to the ctor function
323  *	domain The domain to allocate from.
324  *	flags See sys/malloc.h for available flags.
325  */
326 void *uma_zalloc_domain(uma_zone_t zone, void *arg, int domain, int flags);
327 
328 /*
329  * Allocates an item out of a zone without supplying an argument
330  *
331  * This is just a wrapper for uma_zalloc_arg for convenience.
332  *
333  */
334 static __inline void *uma_zalloc(uma_zone_t zone, int flags);
335 static __inline void *uma_zalloc_pcpu(uma_zone_t zone, int flags);
336 
337 static __inline void *
338 uma_zalloc(uma_zone_t zone, int flags)
339 {
340 	return uma_zalloc_arg(zone, NULL, flags);
341 }
342 
343 static __inline void *
344 uma_zalloc_pcpu(uma_zone_t zone, int flags)
345 {
346 	return uma_zalloc_pcpu_arg(zone, NULL, flags);
347 }
348 
349 /*
350  * Frees an item back into the specified zone.
351  *
352  * Arguments:
353  *	zone  The zone the item was originally allocated out of.
354  *	item  The memory to be freed.
355  *	arg   Argument passed to the destructor
356  *
357  * Returns:
358  *	Nothing.
359  */
360 
361 void uma_zfree_arg(uma_zone_t zone, void *item, void *arg);
362 void uma_zfree_pcpu_arg(uma_zone_t zone, void *item, void *arg);
363 
364 /*
365  * Frees an item back to the specified zone's domain specific pool.
366  *
367  * Arguments:
368  *	zone  The zone the item was originally allocated out of.
369  *	item  The memory to be freed.
370  *	arg   Argument passed to the destructor
371  */
372 void uma_zfree_domain(uma_zone_t zone, void *item, void *arg);
373 
374 /*
375  * Frees an item back to a zone without supplying an argument
376  *
377  * This is just a wrapper for uma_zfree_arg for convenience.
378  *
379  */
380 static __inline void uma_zfree(uma_zone_t zone, void *item);
381 static __inline void uma_zfree_pcpu(uma_zone_t zone, void *item);
382 
383 static __inline void
384 uma_zfree(uma_zone_t zone, void *item)
385 {
386 	uma_zfree_arg(zone, item, NULL);
387 }
388 
389 static __inline void
390 uma_zfree_pcpu(uma_zone_t zone, void *item)
391 {
392 	uma_zfree_pcpu_arg(zone, item, NULL);
393 }
394 
395 /*
396  * Wait until the specified zone can allocate an item.
397  */
398 void uma_zwait(uma_zone_t zone);
399 
400 /*
401  * Backend page supplier routines
402  *
403  * Arguments:
404  *	zone  The zone that is requesting pages.
405  *	size  The number of bytes being requested.
406  *	pflag Flags for these memory pages, see below.
407  *	domain The NUMA domain that we prefer for this allocation.
408  *	wait  Indicates our willingness to block.
409  *
410  * Returns:
411  *	A pointer to the allocated memory or NULL on failure.
412  */
413 
414 typedef void *(*uma_alloc)(uma_zone_t zone, vm_size_t size, int domain,
415     uint8_t *pflag, int wait);
416 
417 /*
418  * Backend page free routines
419  *
420  * Arguments:
421  *	item  A pointer to the previously allocated pages.
422  *	size  The original size of the allocation.
423  *	pflag The flags for the slab.  See UMA_SLAB_* below.
424  *
425  * Returns:
426  *	None
427  */
428 typedef void (*uma_free)(void *item, vm_size_t size, uint8_t pflag);
429 
430 /*
431  * Reclaims unused memory
432  *
433  * Arguments:
434  *	req  Reclamation request type.
435  * Returns:
436  *	None
437  */
438 #define	UMA_RECLAIM_DRAIN	1	/* release bucket cache */
439 #define	UMA_RECLAIM_DRAIN_CPU	2	/* release bucket and per-CPU caches */
440 #define	UMA_RECLAIM_TRIM	3	/* trim bucket cache to WSS */
441 void uma_reclaim(int req);
442 void uma_zone_reclaim(uma_zone_t, int req);
443 
444 /*
445  * Sets the alignment mask to be used for all zones requesting cache
446  * alignment.  Should be called by MD boot code prior to starting VM/UMA.
447  *
448  * Arguments:
449  *	align The alignment mask
450  *
451  * Returns:
452  *	Nothing
453  */
454 void uma_set_align(int align);
455 
456 /*
457  * Set a reserved number of items to hold for M_USE_RESERVE allocations.  All
458  * other requests must allocate new backing pages.
459  */
460 void uma_zone_reserve(uma_zone_t zone, int nitems);
461 
462 /*
463  * Reserves the maximum KVA space required by the zone and configures the zone
464  * to use a VM_ALLOC_NOOBJ-based backend allocator.
465  *
466  * Arguments:
467  *	zone  The zone to update.
468  *	nitems  The upper limit on the number of items that can be allocated.
469  *
470  * Returns:
471  *	0  if KVA space can not be allocated
472  *	1  if successful
473  *
474  * Discussion:
475  *	When the machine supports a direct map and the zone's items are smaller
476  *	than a page, the zone will use the direct map instead of allocating KVA
477  *	space.
478  */
479 int uma_zone_reserve_kva(uma_zone_t zone, int nitems);
480 
481 /*
482  * Sets a high limit on the number of items allowed in a zone
483  *
484  * Arguments:
485  *	zone  The zone to limit
486  *	nitems  The requested upper limit on the number of items allowed
487  *
488  * Returns:
489  *	int  The effective value of nitems
490  */
491 int uma_zone_set_max(uma_zone_t zone, int nitems);
492 
493 /*
494  * Sets a high limit on the number of items allowed in zone's bucket cache
495  *
496  * Arguments:
497  *      zone  The zone to limit
498  *      nitems  The requested upper limit on the number of items allowed
499  */
500 void uma_zone_set_maxcache(uma_zone_t zone, int nitems);
501 
502 /*
503  * Obtains the effective limit on the number of items in a zone
504  *
505  * Arguments:
506  *	zone  The zone to obtain the effective limit from
507  *
508  * Return:
509  *	0  No limit
510  *	int  The effective limit of the zone
511  */
512 int uma_zone_get_max(uma_zone_t zone);
513 
514 /*
515  * Sets a warning to be printed when limit is reached
516  *
517  * Arguments:
518  *	zone  The zone we will warn about
519  *	warning  Warning content
520  *
521  * Returns:
522  *	Nothing
523  */
524 void uma_zone_set_warning(uma_zone_t zone, const char *warning);
525 
526 /*
527  * Sets a function to run when limit is reached
528  *
529  * Arguments:
530  *	zone  The zone to which this applies
531  *	fx  The function ro run
532  *
533  * Returns:
534  *	Nothing
535  */
536 typedef void (*uma_maxaction_t)(uma_zone_t, int);
537 void uma_zone_set_maxaction(uma_zone_t zone, uma_maxaction_t);
538 
539 /*
540  * Obtains the approximate current number of items allocated from a zone
541  *
542  * Arguments:
543  *	zone  The zone to obtain the current allocation count from
544  *
545  * Return:
546  *	int  The approximate current number of items allocated from the zone
547  */
548 int uma_zone_get_cur(uma_zone_t zone);
549 
550 /*
551  * The following two routines (uma_zone_set_init/fini)
552  * are used to set the backend init/fini pair which acts on an
553  * object as it becomes allocated and is placed in a slab within
554  * the specified zone's backing keg.  These should probably not
555  * be changed once allocations have already begun, but only be set
556  * immediately upon zone creation.
557  */
558 void uma_zone_set_init(uma_zone_t zone, uma_init uminit);
559 void uma_zone_set_fini(uma_zone_t zone, uma_fini fini);
560 
561 /*
562  * The following two routines (uma_zone_set_zinit/zfini) are
563  * used to set the zinit/zfini pair which acts on an object as
564  * it passes from the backing Keg's slab cache to the
565  * specified Zone's bucket cache.  These should probably not
566  * be changed once allocations have already begun, but only be set
567  * immediately upon zone creation.
568  */
569 void uma_zone_set_zinit(uma_zone_t zone, uma_init zinit);
570 void uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini);
571 
572 /*
573  * Replaces the standard backend allocator for this zone.
574  *
575  * Arguments:
576  *	zone   The zone whose backend allocator is being changed.
577  *	allocf A pointer to the allocation function
578  *
579  * Returns:
580  *	Nothing
581  *
582  * Discussion:
583  *	This could be used to implement pageable allocation, or perhaps
584  *	even DMA allocators if used in conjunction with the OFFPAGE
585  *	zone flag.
586  */
587 
588 void uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf);
589 
590 /*
591  * Used for freeing memory provided by the allocf above
592  *
593  * Arguments:
594  *	zone  The zone that intends to use this free routine.
595  *	freef The page freeing routine.
596  *
597  * Returns:
598  *	Nothing
599  */
600 
601 void uma_zone_set_freef(uma_zone_t zone, uma_free freef);
602 
603 /*
604  * These flags are setable in the allocf and visible in the freef.
605  */
606 #define UMA_SLAB_BOOT	0x01		/* Slab alloced from boot pages */
607 #define UMA_SLAB_KERNEL	0x04		/* Slab alloced from kmem */
608 #define UMA_SLAB_PRIV	0x08		/* Slab alloced from priv allocator */
609 #define UMA_SLAB_OFFP	0x10		/* Slab is managed separately  */
610 /* 0x02, 0x40, and 0x80 are available */
611 
612 /*
613  * Used to pre-fill a zone with some number of items
614  *
615  * Arguments:
616  *	zone    The zone to fill
617  *	itemcnt The number of items to reserve
618  *
619  * Returns:
620  *	Nothing
621  *
622  * NOTE: This is blocking and should only be done at startup
623  */
624 void uma_prealloc(uma_zone_t zone, int itemcnt);
625 
626 /*
627  * Used to determine if a fixed-size zone is exhausted.
628  *
629  * Arguments:
630  *	zone    The zone to check
631  *
632  * Returns:
633  *	Non-zero if zone is exhausted.
634  */
635 int uma_zone_exhausted(uma_zone_t zone);
636 
637 /*
638  * Common UMA_ZONE_PCPU zones.
639  */
640 extern uma_zone_t pcpu_zone_int;
641 extern uma_zone_t pcpu_zone_64;
642 
643 /*
644  * Exported statistics structures to be used by user space monitoring tools.
645  * Statistics stream consists of a uma_stream_header, followed by a series of
646  * alternative uma_type_header and uma_type_stat structures.
647  */
648 #define	UMA_STREAM_VERSION	0x00000001
649 struct uma_stream_header {
650 	uint32_t	ush_version;	/* Stream format version. */
651 	uint32_t	ush_maxcpus;	/* Value of MAXCPU for stream. */
652 	uint32_t	ush_count;	/* Number of records. */
653 	uint32_t	_ush_pad;	/* Pad/reserved field. */
654 };
655 
656 #define	UTH_MAX_NAME	32
657 #define	UTH_ZONE_SECONDARY	0x00000001
658 struct uma_type_header {
659 	/*
660 	 * Static per-zone data, some extracted from the supporting keg.
661 	 */
662 	char		uth_name[UTH_MAX_NAME];
663 	uint32_t	uth_align;	/* Keg: alignment. */
664 	uint32_t	uth_size;	/* Keg: requested size of item. */
665 	uint32_t	uth_rsize;	/* Keg: real size of item. */
666 	uint32_t	uth_maxpages;	/* Keg: maximum number of pages. */
667 	uint32_t	uth_limit;	/* Keg: max items to allocate. */
668 
669 	/*
670 	 * Current dynamic zone/keg-derived statistics.
671 	 */
672 	uint32_t	uth_pages;	/* Keg: pages allocated. */
673 	uint32_t	uth_keg_free;	/* Keg: items free. */
674 	uint32_t	uth_zone_free;	/* Zone: items free. */
675 	uint32_t	uth_bucketsize;	/* Zone: desired bucket size. */
676 	uint32_t	uth_zone_flags;	/* Zone: flags. */
677 	uint64_t	uth_allocs;	/* Zone: number of allocations. */
678 	uint64_t	uth_frees;	/* Zone: number of frees. */
679 	uint64_t	uth_fails;	/* Zone: number of alloc failures. */
680 	uint64_t	uth_sleeps;	/* Zone: number of alloc sleeps. */
681 	uint64_t	uth_xdomain;	/* Zone: Number of cross domain frees. */
682 	uint64_t	_uth_reserved1[1];	/* Reserved. */
683 };
684 
685 struct uma_percpu_stat {
686 	uint64_t	ups_allocs;	/* Cache: number of allocations. */
687 	uint64_t	ups_frees;	/* Cache: number of frees. */
688 	uint64_t	ups_cache_free;	/* Cache: free items in cache. */
689 	uint64_t	_ups_reserved[5];	/* Reserved. */
690 };
691 
692 void uma_reclaim_wakeup(void);
693 void uma_reclaim_worker(void *);
694 
695 unsigned long uma_limit(void);
696 
697 /* Return the amount of memory managed by UMA. */
698 unsigned long uma_size(void);
699 
700 /* Return the amount of memory remaining.  May be negative. */
701 long uma_avail(void);
702 
703 #endif	/* _VM_UMA_H_ */
704