xref: /freebsd/sys/vm/uma.h (revision 5ab1c5846ff41be24b1f6beb0317bf8258cd4409)
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       (PAGE_SIZE / 256) /* 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.  0xff000000 is in use by uma_int.h.
236  */
237 #define UMA_ZONE_PAGEABLE	0x0001	/* Return items not fully backed by
238 					   physical memory XXX Not yet */
239 #define UMA_ZONE_ZINIT		0x0002	/* Initialize with zeros */
240 #define UMA_ZONE_STATIC		0x0004	/* Statically sized zone */
241 #define UMA_ZONE_OFFPAGE	0x0008	/* Force the slab structure allocation
242 					   off of the real memory */
243 #define UMA_ZONE_MALLOC		0x0010	/* For use by malloc(9) only! */
244 #define UMA_ZONE_NOFREE		0x0020	/* Do not free slabs of this type! */
245 #define UMA_ZONE_MTXCLASS	0x0040	/* Create a new lock class */
246 #define	UMA_ZONE_VM		0x0080	/*
247 					 * Used for internal vm datastructures
248 					 * only.
249 					 */
250 #define	UMA_ZONE_HASH		0x0100	/*
251 					 * Use a hash table instead of caching
252 					 * information in the vm_page.
253 					 */
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	0x1000	/*
258 					 * Spread memory start locations across
259 					 * all possible cache lines.  May
260 					 * require many virtually contiguous
261 					 * backend pages and can fail early.
262 					 */
263 #define	UMA_ZONE_VTOSLAB	0x2000	/* Zone uses vtoslab for lookup. */
264 #define	UMA_ZONE_NODUMP		0x4000	/*
265 					 * Zone's pages will not be included in
266 					 * mini-dumps.
267 					 */
268 #define	UMA_ZONE_PCPU		0x8000	/*
269 					 * Allocates mp_maxid + 1 slabs of PAGE_SIZE
270 					 */
271 #define	UMA_ZONE_NUMA		0x10000	/*
272 					 * NUMA aware Zone.  Implements a best
273 					 * effort first-touch policy.
274 					 */
275 #define	UMA_ZONE_MINBUCKET	0x20000	/* Use smallest buckets. */
276 
277 /*
278  * These flags are shared between the keg and zone.  In zones wishing to add
279  * new kegs these flags must be compatible.  Some are determined based on
280  * physical parameters of the request and may not be provided by the consumer.
281  */
282 #define	UMA_ZONE_INHERIT						\
283     (UMA_ZONE_OFFPAGE | UMA_ZONE_MALLOC | UMA_ZONE_NOFREE |		\
284     UMA_ZONE_HASH | UMA_ZONE_VTOSLAB | UMA_ZONE_PCPU | UMA_ZONE_NUMA)
285 
286 /* Definitions for align */
287 #define UMA_ALIGN_PTR	(sizeof(void *) - 1)	/* Alignment fit for ptr */
288 #define UMA_ALIGN_LONG	(sizeof(long) - 1)	/* "" long */
289 #define UMA_ALIGN_INT	(sizeof(int) - 1)	/* "" int */
290 #define UMA_ALIGN_SHORT	(sizeof(short) - 1)	/* "" short */
291 #define UMA_ALIGN_CHAR	(sizeof(char) - 1)	/* "" char */
292 #define UMA_ALIGN_CACHE	(0 - 1)			/* Cache line size align */
293 #define	UMA_ALIGNOF(type) (_Alignof(type) - 1)	/* Alignment fit for 'type' */
294 
295 #define	UMA_ANYDOMAIN	-1	/* Special value for domain search. */
296 
297 /*
298  * Destroys an empty uma zone.  If the zone is not empty uma complains loudly.
299  *
300  * Arguments:
301  *	zone  The zone we want to destroy.
302  *
303  */
304 void uma_zdestroy(uma_zone_t zone);
305 
306 /*
307  * Allocates an item out of a zone
308  *
309  * Arguments:
310  *	zone  The zone we are allocating from
311  *	arg   This data is passed to the ctor function
312  *	flags See sys/malloc.h for available flags.
313  *
314  * Returns:
315  *	A non-null pointer to an initialized element from the zone is
316  *	guaranteed if the wait flag is M_WAITOK.  Otherwise a null pointer
317  *	may be returned if the zone is empty or the ctor failed.
318  */
319 
320 void *uma_zalloc_arg(uma_zone_t zone, void *arg, int flags);
321 void *uma_zalloc_pcpu_arg(uma_zone_t zone, void *arg, int flags);
322 
323 /*
324  * Allocate an item from a specific NUMA domain.  This uses a slow path in
325  * the allocator but is guaranteed to allocate memory from the requested
326  * domain if M_WAITOK is set.
327  *
328  * Arguments:
329  *	zone  The zone we are allocating from
330  *	arg   This data is passed to the ctor function
331  *	domain The domain to allocate from.
332  *	flags See sys/malloc.h for available flags.
333  */
334 void *uma_zalloc_domain(uma_zone_t zone, void *arg, int domain, int flags);
335 
336 /*
337  * Allocates an item out of a zone without supplying an argument
338  *
339  * This is just a wrapper for uma_zalloc_arg for convenience.
340  *
341  */
342 static __inline void *uma_zalloc(uma_zone_t zone, int flags);
343 static __inline void *uma_zalloc_pcpu(uma_zone_t zone, int flags);
344 
345 static __inline void *
346 uma_zalloc(uma_zone_t zone, int flags)
347 {
348 	return uma_zalloc_arg(zone, NULL, flags);
349 }
350 
351 static __inline void *
352 uma_zalloc_pcpu(uma_zone_t zone, int flags)
353 {
354 	return uma_zalloc_pcpu_arg(zone, NULL, flags);
355 }
356 
357 /*
358  * Frees an item back into the specified zone.
359  *
360  * Arguments:
361  *	zone  The zone the item was originally allocated out of.
362  *	item  The memory to be freed.
363  *	arg   Argument passed to the destructor
364  *
365  * Returns:
366  *	Nothing.
367  */
368 
369 void uma_zfree_arg(uma_zone_t zone, void *item, void *arg);
370 void uma_zfree_pcpu_arg(uma_zone_t zone, void *item, void *arg);
371 
372 /*
373  * Frees an item back to the specified zone's domain specific pool.
374  *
375  * Arguments:
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
379  */
380 void uma_zfree_domain(uma_zone_t zone, void *item, void *arg);
381 
382 /*
383  * Frees an item back to a zone without supplying an argument
384  *
385  * This is just a wrapper for uma_zfree_arg for convenience.
386  *
387  */
388 static __inline void uma_zfree(uma_zone_t zone, void *item);
389 static __inline void uma_zfree_pcpu(uma_zone_t zone, void *item);
390 
391 static __inline void
392 uma_zfree(uma_zone_t zone, void *item)
393 {
394 	uma_zfree_arg(zone, item, NULL);
395 }
396 
397 static __inline void
398 uma_zfree_pcpu(uma_zone_t zone, void *item)
399 {
400 	uma_zfree_pcpu_arg(zone, item, NULL);
401 }
402 
403 /*
404  * Wait until the specified zone can allocate an item.
405  */
406 void uma_zwait(uma_zone_t zone);
407 
408 /*
409  * Backend page supplier routines
410  *
411  * Arguments:
412  *	zone  The zone that is requesting pages.
413  *	size  The number of bytes being requested.
414  *	pflag Flags for these memory pages, see below.
415  *	domain The NUMA domain that we prefer for this allocation.
416  *	wait  Indicates our willingness to block.
417  *
418  * Returns:
419  *	A pointer to the allocated memory or NULL on failure.
420  */
421 
422 typedef void *(*uma_alloc)(uma_zone_t zone, vm_size_t size, int domain,
423     uint8_t *pflag, int wait);
424 
425 /*
426  * Backend page free routines
427  *
428  * Arguments:
429  *	item  A pointer to the previously allocated pages.
430  *	size  The original size of the allocation.
431  *	pflag The flags for the slab.  See UMA_SLAB_* below.
432  *
433  * Returns:
434  *	None
435  */
436 typedef void (*uma_free)(void *item, vm_size_t size, uint8_t pflag);
437 
438 /*
439  * Reclaims unused memory
440  *
441  * Arguments:
442  *	req  Reclamation request type.
443  * Returns:
444  *	None
445  */
446 #define	UMA_RECLAIM_DRAIN	1	/* release bucket cache */
447 #define	UMA_RECLAIM_DRAIN_CPU	2	/* release bucket and per-CPU caches */
448 #define	UMA_RECLAIM_TRIM	3	/* trim bucket cache to WSS */
449 void uma_reclaim(int req);
450 void uma_zone_reclaim(uma_zone_t, int req);
451 
452 /*
453  * Sets the alignment mask to be used for all zones requesting cache
454  * alignment.  Should be called by MD boot code prior to starting VM/UMA.
455  *
456  * Arguments:
457  *	align The alignment mask
458  *
459  * Returns:
460  *	Nothing
461  */
462 void uma_set_align(int align);
463 
464 /*
465  * Set a reserved number of items to hold for M_USE_RESERVE allocations.  All
466  * other requests must allocate new backing pages.
467  */
468 void uma_zone_reserve(uma_zone_t zone, int nitems);
469 
470 /*
471  * Reserves the maximum KVA space required by the zone and configures the zone
472  * to use a VM_ALLOC_NOOBJ-based backend allocator.
473  *
474  * Arguments:
475  *	zone  The zone to update.
476  *	nitems  The upper limit on the number of items that can be allocated.
477  *
478  * Returns:
479  *	0  if KVA space can not be allocated
480  *	1  if successful
481  *
482  * Discussion:
483  *	When the machine supports a direct map and the zone's items are smaller
484  *	than a page, the zone will use the direct map instead of allocating KVA
485  *	space.
486  */
487 int uma_zone_reserve_kva(uma_zone_t zone, int nitems);
488 
489 /*
490  * Sets a high limit on the number of items allowed in a zone
491  *
492  * Arguments:
493  *	zone  The zone to limit
494  *	nitems  The requested upper limit on the number of items allowed
495  *
496  * Returns:
497  *	int  The effective value of nitems
498  */
499 int uma_zone_set_max(uma_zone_t zone, int nitems);
500 
501 /*
502  * Sets a high limit on the number of items allowed in zone's bucket cache
503  *
504  * Arguments:
505  *      zone  The zone to limit
506  *      nitems  The requested upper limit on the number of items allowed
507  */
508 void uma_zone_set_maxcache(uma_zone_t zone, int nitems);
509 
510 /*
511  * Obtains the effective limit on the number of items in a zone
512  *
513  * Arguments:
514  *	zone  The zone to obtain the effective limit from
515  *
516  * Return:
517  *	0  No limit
518  *	int  The effective limit of the zone
519  */
520 int uma_zone_get_max(uma_zone_t zone);
521 
522 /*
523  * Sets a warning to be printed when limit is reached
524  *
525  * Arguments:
526  *	zone  The zone we will warn about
527  *	warning  Warning content
528  *
529  * Returns:
530  *	Nothing
531  */
532 void uma_zone_set_warning(uma_zone_t zone, const char *warning);
533 
534 /*
535  * Sets a function to run when limit is reached
536  *
537  * Arguments:
538  *	zone  The zone to which this applies
539  *	fx  The function ro run
540  *
541  * Returns:
542  *	Nothing
543  */
544 typedef void (*uma_maxaction_t)(uma_zone_t, int);
545 void uma_zone_set_maxaction(uma_zone_t zone, uma_maxaction_t);
546 
547 /*
548  * Obtains the approximate current number of items allocated from a zone
549  *
550  * Arguments:
551  *	zone  The zone to obtain the current allocation count from
552  *
553  * Return:
554  *	int  The approximate current number of items allocated from the zone
555  */
556 int uma_zone_get_cur(uma_zone_t zone);
557 
558 /*
559  * The following two routines (uma_zone_set_init/fini)
560  * are used to set the backend init/fini pair which acts on an
561  * object as it becomes allocated and is placed in a slab within
562  * the specified zone's backing keg.  These should probably not
563  * be changed once allocations have already begun, but only be set
564  * immediately upon zone creation.
565  */
566 void uma_zone_set_init(uma_zone_t zone, uma_init uminit);
567 void uma_zone_set_fini(uma_zone_t zone, uma_fini fini);
568 
569 /*
570  * The following two routines (uma_zone_set_zinit/zfini) are
571  * used to set the zinit/zfini pair which acts on an object as
572  * it passes from the backing Keg's slab cache to the
573  * specified Zone's bucket cache.  These should probably not
574  * be changed once allocations have already begun, but only be set
575  * immediately upon zone creation.
576  */
577 void uma_zone_set_zinit(uma_zone_t zone, uma_init zinit);
578 void uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini);
579 
580 /*
581  * Replaces the standard backend allocator for this zone.
582  *
583  * Arguments:
584  *	zone   The zone whose backend allocator is being changed.
585  *	allocf A pointer to the allocation function
586  *
587  * Returns:
588  *	Nothing
589  *
590  * Discussion:
591  *	This could be used to implement pageable allocation, or perhaps
592  *	even DMA allocators if used in conjunction with the OFFPAGE
593  *	zone flag.
594  */
595 
596 void uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf);
597 
598 /*
599  * Used for freeing memory provided by the allocf above
600  *
601  * Arguments:
602  *	zone  The zone that intends to use this free routine.
603  *	freef The page freeing routine.
604  *
605  * Returns:
606  *	Nothing
607  */
608 
609 void uma_zone_set_freef(uma_zone_t zone, uma_free freef);
610 
611 /*
612  * These flags are setable in the allocf and visible in the freef.
613  */
614 #define UMA_SLAB_BOOT	0x01		/* Slab alloced from boot pages */
615 #define UMA_SLAB_KERNEL	0x04		/* Slab alloced from kmem */
616 #define UMA_SLAB_PRIV	0x08		/* Slab alloced from priv allocator */
617 #define UMA_SLAB_OFFP	0x10		/* Slab is managed separately  */
618 /* 0x02, 0x40, and 0x80 are available */
619 
620 /*
621  * Used to pre-fill a zone with some number of items
622  *
623  * Arguments:
624  *	zone    The zone to fill
625  *	itemcnt The number of items to reserve
626  *
627  * Returns:
628  *	Nothing
629  *
630  * NOTE: This is blocking and should only be done at startup
631  */
632 void uma_prealloc(uma_zone_t zone, int itemcnt);
633 
634 /*
635  * Used to determine if a fixed-size zone is exhausted.
636  *
637  * Arguments:
638  *	zone    The zone to check
639  *
640  * Returns:
641  *	Non-zero if zone is exhausted.
642  */
643 int uma_zone_exhausted(uma_zone_t zone);
644 int uma_zone_exhausted_nolock(uma_zone_t zone);
645 
646 /*
647  * Common UMA_ZONE_PCPU zones.
648  */
649 extern uma_zone_t pcpu_zone_int;
650 extern uma_zone_t pcpu_zone_64;
651 
652 /*
653  * Exported statistics structures to be used by user space monitoring tools.
654  * Statistics stream consists of a uma_stream_header, followed by a series of
655  * alternative uma_type_header and uma_type_stat structures.
656  */
657 #define	UMA_STREAM_VERSION	0x00000001
658 struct uma_stream_header {
659 	uint32_t	ush_version;	/* Stream format version. */
660 	uint32_t	ush_maxcpus;	/* Value of MAXCPU for stream. */
661 	uint32_t	ush_count;	/* Number of records. */
662 	uint32_t	_ush_pad;	/* Pad/reserved field. */
663 };
664 
665 #define	UTH_MAX_NAME	32
666 #define	UTH_ZONE_SECONDARY	0x00000001
667 struct uma_type_header {
668 	/*
669 	 * Static per-zone data, some extracted from the supporting keg.
670 	 */
671 	char		uth_name[UTH_MAX_NAME];
672 	uint32_t	uth_align;	/* Keg: alignment. */
673 	uint32_t	uth_size;	/* Keg: requested size of item. */
674 	uint32_t	uth_rsize;	/* Keg: real size of item. */
675 	uint32_t	uth_maxpages;	/* Keg: maximum number of pages. */
676 	uint32_t	uth_limit;	/* Keg: max items to allocate. */
677 
678 	/*
679 	 * Current dynamic zone/keg-derived statistics.
680 	 */
681 	uint32_t	uth_pages;	/* Keg: pages allocated. */
682 	uint32_t	uth_keg_free;	/* Keg: items free. */
683 	uint32_t	uth_zone_free;	/* Zone: items free. */
684 	uint32_t	uth_bucketsize;	/* Zone: desired bucket size. */
685 	uint32_t	uth_zone_flags;	/* Zone: flags. */
686 	uint64_t	uth_allocs;	/* Zone: number of allocations. */
687 	uint64_t	uth_frees;	/* Zone: number of frees. */
688 	uint64_t	uth_fails;	/* Zone: number of alloc failures. */
689 	uint64_t	uth_sleeps;	/* Zone: number of alloc sleeps. */
690 	uint64_t	uth_xdomain;	/* Zone: Number of cross domain frees. */
691 	uint64_t	_uth_reserved1[1];	/* Reserved. */
692 };
693 
694 struct uma_percpu_stat {
695 	uint64_t	ups_allocs;	/* Cache: number of allocations. */
696 	uint64_t	ups_frees;	/* Cache: number of frees. */
697 	uint64_t	ups_cache_free;	/* Cache: free items in cache. */
698 	uint64_t	_ups_reserved[5];	/* Reserved. */
699 };
700 
701 void uma_reclaim_wakeup(void);
702 void uma_reclaim_worker(void *);
703 
704 unsigned long uma_limit(void);
705 
706 /* Return the amount of memory managed by UMA. */
707 unsigned long uma_size(void);
708 
709 /* Return the amount of memory remaining.  May be negative. */
710 long uma_avail(void);
711 
712 #endif	/* _VM_UMA_H_ */
713