1/*-
2 * Copyright (c) 2002, 2003, 2004, 2005 Jeffrey Roberson <jeff@FreeBSD.org>
3 * Copyright (c) 2004, 2005 Bosko Milekic <bmilekic@FreeBSD.org>
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice unmodified, this list of conditions, and the following
11 * disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 *
27 * $FreeBSD: head/sys/vm/uma.h 244024 2012-12-08 09:23:05Z pjd $
28 *
29 */
30
31/*
32 * uma.h - External definitions for the Universal Memory Allocator
33 *
34*/
35
36#ifndef VM_UMA_H
37#define VM_UMA_H
38
39#include <sys/param.h> /* For NULL */
40#include <sys/malloc.h> /* For M_* */
41
42/* User visible parameters */
43#define UMA_SMALLEST_UNIT (PAGE_SIZE / 256) /* Smallest item allocated */
44
45/* Types and type defs */
46
47struct uma_zone;
48/* Opaque type used as a handle to the zone */
49typedef struct uma_zone * uma_zone_t;
50
51void zone_drain(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 */
70typedef 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 */
88typedef 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 */
107typedef 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 */
124typedef void (*uma_fini)(void *mem, int size);
125
126/*
127 * What's the difference between initializing and constructing?
128 *
129 * The item is initialized when it is cached, and this is the state that the
130 * object should be in when returned to the allocator. The purpose of this is
131 * to remove some code which would otherwise be called on each allocation by
132 * utilizing a known, stable state. This differs from the constructor which
133 * will be called on EVERY allocation.
134 *
135 * For example, in the initializer you may want to initialize embedded locks,
136 * NULL list pointers, set up initial states, magic numbers, etc. This way if
137 * the object is held in the allocator and re-used it won't be necessary to
138 * re-initialize it.
139 *
140 * The constructor may be used to lock a data structure, link it on to lists,
141 * bump reference counts or total counts of outstanding structures, etc.
142 *
143 */
144
145
146/* Function proto types */
147
148/*
149 * Create a new uma zone
150 *
151 * Arguments:
152 * name The text name of the zone for debugging and stats. This memory
153 * should not be freed until the zone has been deallocated.
154 * size The size of the object that is being created.
155 * ctor The constructor that is called when the object is allocated.
156 * dtor The destructor that is called when the object is freed.
157 * init An initializer that sets up the initial state of the memory.
158 * fini A discard function that undoes initialization done by init.
159 * ctor/dtor/init/fini may all be null, see notes above.
160 * align A bitmask that corresponds to the requested alignment
161 * eg 4 would be 0x3
162 * flags A set of parameters that control the behavior of the zone.
163 *
164 * Returns:
165 * A pointer to a structure which is intended to be opaque to users of
166 * the interface. The value may be null if the wait flag is not set.
167 */
168uma_zone_t uma_zcreate(const char *name, size_t size, uma_ctor ctor,
169 uma_dtor dtor, uma_init uminit, uma_fini fini,
170 int align, u_int32_t flags);
171
172/*
173 * Create a secondary uma zone
174 *
175 * Arguments:
176 * name The text name of the zone for debugging and stats. This memory
177 * should not be freed until the zone has been deallocated.
178 * ctor The constructor that is called when the object is allocated.
179 * dtor The destructor that is called when the object is freed.
180 * zinit An initializer that sets up the initial state of the memory
181 * as the object passes from the Keg's slab to the Zone's cache.
182 * zfini A discard function that undoes initialization done by init
183 * as the object passes from the Zone's cache to the Keg's slab.
184 *
185 * ctor/dtor/zinit/zfini may all be null, see notes above.
186 * Note that the zinit and zfini specified here are NOT
187 * exactly the same as the init/fini specified to uma_zcreate()
188 * when creating a master zone. These zinit/zfini are called
189 * on the TRANSITION from keg to zone (and vice-versa). Once
190 * these are set, the primary zone may alter its init/fini
191 * (which are called when the object passes from VM to keg)
192 * using uma_zone_set_init/fini()) as well as its own
193 * zinit/zfini (unset by default for master zone) with
194 * uma_zone_set_zinit/zfini() (note subtle 'z' prefix).
195 *
196 * master A reference to this zone's Master Zone (Primary Zone),
197 * which contains the backing Keg for the Secondary Zone
198 * being added.
199 *
200 * Returns:
201 * A pointer to a structure which is intended to be opaque to users of
202 * the interface. The value may be null if the wait flag is not set.
203 */
204uma_zone_t uma_zsecond_create(char *name, uma_ctor ctor, uma_dtor dtor,
205 uma_init zinit, uma_fini zfini, uma_zone_t master);
206
207/*
208 * Add a second master to a secondary zone. This provides multiple data
209 * backends for objects with the same size. Both masters must have
210 * compatible allocation flags. Presently, UMA_ZONE_MALLOC type zones are
211 * the only supported.
212 *
213 * Returns:
214 * Error on failure, 0 on success.
215 */
216int uma_zsecond_add(uma_zone_t zone, uma_zone_t master);
217
218/*
219 * Definitions for uma_zcreate flags
220 *
221 * These flags share space with UMA_ZFLAGs in uma_int.h. Be careful not to
222 * overlap when adding new features. 0xf0000000 is in use by uma_int.h.
223 */
224#define UMA_ZONE_PAGEABLE 0x0001 /* Return items not fully backed by
225 physical memory XXX Not yet */
226#define UMA_ZONE_ZINIT 0x0002 /* Initialize with zeros */
227#define UMA_ZONE_STATIC 0x0004 /* Statically sized zone */
228#define UMA_ZONE_OFFPAGE 0x0008 /* Force the slab structure allocation
229 off of the real memory */
230#define UMA_ZONE_MALLOC 0x0010 /* For use by malloc(9) only! */
231#define UMA_ZONE_NOFREE 0x0020 /* Do not free slabs of this type! */
232#define UMA_ZONE_MTXCLASS 0x0040 /* Create a new lock class */
233#define UMA_ZONE_VM 0x0080 /*
234 * Used for internal vm datastructures
235 * only.
236 */
237#define UMA_ZONE_HASH 0x0100 /*
238 * Use a hash table instead of caching
239 * information in the vm_page.
240 */
241#define UMA_ZONE_SECONDARY 0x0200 /* Zone is a Secondary Zone */
242#define UMA_ZONE_REFCNT 0x0400 /* Allocate refcnts in slabs */
243#define UMA_ZONE_MAXBUCKET 0x0800 /* Use largest buckets */
244#define UMA_ZONE_CACHESPREAD 0x1000 /*
245 * Spread memory start locations across
246 * all possible cache lines. May
247 * require many virtually contiguous
248 * backend pages and can fail early.
249 */
250#define UMA_ZONE_VTOSLAB 0x2000 /* Zone uses vtoslab for lookup. */
251#define UMA_ZONE_NODUMP 0x4000 /*
252 * Zone's pages will not be included in
253 * mini-dumps.
254 */
255
256/*
257 * These flags are shared between the keg and zone. In zones wishing to add
258 * new kegs these flags must be compatible. Some are determined based on
259 * physical parameters of the request and may not be provided by the consumer.
260 */
261#define UMA_ZONE_INHERIT \
262 (UMA_ZONE_OFFPAGE | UMA_ZONE_MALLOC | UMA_ZONE_NOFREE | \
263 UMA_ZONE_HASH | UMA_ZONE_REFCNT | UMA_ZONE_VTOSLAB)
264
265/* Definitions for align */
266#define UMA_ALIGN_PTR (sizeof(void *) - 1) /* Alignment fit for ptr */
267#define UMA_ALIGN_LONG (sizeof(long) - 1) /* "" long */
268#define UMA_ALIGN_INT (sizeof(int) - 1) /* "" int */
269#define UMA_ALIGN_SHORT (sizeof(short) - 1) /* "" short */
270#define UMA_ALIGN_CHAR (sizeof(char) - 1) /* "" char */
271#define UMA_ALIGN_CACHE (0 - 1) /* Cache line size align */
272
273/*
274 * Destroys an empty uma zone. If the zone is not empty uma complains loudly.
275 *
276 * Arguments:
277 * zone The zone we want to destroy.
278 *
279 */
280void uma_zdestroy(uma_zone_t zone);
281
282/*
283 * Allocates an item out of a zone
284 *
285 * Arguments:
286 * zone The zone we are allocating from
287 * arg This data is passed to the ctor function
288 * flags See sys/malloc.h for available flags.
289 *
290 * Returns:
291 * A non-null pointer to an initialized element from the zone is
292 * guaranteed if the wait flag is M_WAITOK. Otherwise a null pointer
293 * may be returned if the zone is empty or the ctor failed.
294 */
295
296void *uma_zalloc_arg(uma_zone_t zone, void *arg, int flags);
297
298/*
299 * Allocates an item out of a zone without supplying an argument
300 *
301 * This is just a wrapper for uma_zalloc_arg for convenience.
302 *
303 */
304static __inline void *uma_zalloc(uma_zone_t zone, int flags);
305
306static __inline void *
307uma_zalloc(uma_zone_t zone, int flags)
308{
309 return uma_zalloc_arg(zone, NULL, flags);
310}
311
312/*
313 * Frees an item back into the specified zone.
314 *
315 * Arguments:
316 * zone The zone the item was originally allocated out of.
317 * item The memory to be freed.
318 * arg Argument passed to the destructor
319 *
320 * Returns:
321 * Nothing.
322 */
323
324void uma_zfree_arg(uma_zone_t zone, void *item, void *arg);
325
326/*
327 * Frees an item back to a zone without supplying an argument
328 *
329 * This is just a wrapper for uma_zfree_arg for convenience.
330 *
331 */
332static __inline void uma_zfree(uma_zone_t zone, void *item);
333
334static __inline void
335uma_zfree(uma_zone_t zone, void *item)
336{
337 uma_zfree_arg(zone, item, NULL);
338}
339
340/*
341 * XXX The rest of the prototypes in this header are h0h0 magic for the VM.
342 * If you think you need to use it for a normal zone you're probably incorrect.
343 */
344
345/*
346 * Backend page supplier routines
347 *
348 * Arguments:
349 * zone The zone that is requesting pages.
350 * size The number of bytes being requested.
351 * pflag Flags for these memory pages, see below.
352 * wait Indicates our willingness to block.
353 *
354 * Returns:
355 * A pointer to the allocated memory or NULL on failure.
356 */
357
358typedef void *(*uma_alloc)(uma_zone_t zone, int size, u_int8_t *pflag, int wait);
359
360/*
361 * Backend page free routines
362 *
363 * Arguments:
364 * item A pointer to the previously allocated pages.
365 * size The original size of the allocation.
366 * pflag The flags for the slab. See UMA_SLAB_* below.
367 *
368 * Returns:
369 * None
370 */
371typedef void (*uma_free)(void *item, int size, u_int8_t pflag);
372
373
374
375/*
376 * Sets up the uma allocator. (Called by vm_mem_init)
377 *
378 * Arguments:
379 * bootmem A pointer to memory used to bootstrap the system.
380 *
381 * Returns:
382 * Nothing
383 *
384 * Discussion:
385 * This memory is used for zones which allocate things before the
386 * backend page supplier can give us pages. It should be
387 * UMA_SLAB_SIZE * boot_pages bytes. (see uma_int.h)
388 *
389 */
390
391void uma_startup(void *bootmem, int boot_pages);
392
393/*
394 * Finishes starting up the allocator. This should
395 * be called when kva is ready for normal allocs.
396 *
397 * Arguments:
398 * None
399 *
400 * Returns:
401 * Nothing
402 *
403 * Discussion:
404 * uma_startup2 is called by kmeminit() to enable us of uma for malloc.
405 */
406
407void uma_startup2(void);
408
409/*
410 * Reclaims unused memory for all zones
411 *
412 * Arguments:
413 * None
414 * Returns:
415 * None
416 *
417 * This should only be called by the page out daemon.
418 */
419
420void uma_reclaim(void);
421
422/*
423 * Sets the alignment mask to be used for all zones requesting cache
424 * alignment. Should be called by MD boot code prior to starting VM/UMA.
425 *
426 * Arguments:
427 * align The alignment mask
428 *
429 * Returns:
430 * Nothing
431 */
432void uma_set_align(int align);
433
434/*
435 * Switches the backing object of a zone
436 *
437 * Arguments:
438 * zone The zone to update.
439 * obj The VM object to use for future allocations.
440 * size The size of the object to allocate.
441 *
442 * Returns:
443 * 0 if kva space can not be allocated
444 * 1 if successful
445 *
446 * Discussion:
447 * A NULL object can be used and uma will allocate one for you. Setting
448 * the size will limit the amount of memory allocated to this zone.
449 *
450 */
451struct vm_object;
452int uma_zone_set_obj(uma_zone_t zone, struct vm_object *obj, int size);
453
454/*
455 * Sets a high limit on the number of items allowed in a zone
456 *
457 * Arguments:
458 * zone The zone to limit
459 * nitems The requested upper limit on the number of items allowed
460 *
461 * Returns:
462 * int The effective value of nitems after rounding up based on page size
463 */
464int uma_zone_set_max(uma_zone_t zone, int nitems);
465
466/*
467 * Obtains the effective limit on the number of items in a zone
468 *
469 * Arguments:
470 * zone The zone to obtain the effective limit from
471 *
472 * Return:
473 * 0 No limit
474 * int The effective limit of the zone
475 */
476int uma_zone_get_max(uma_zone_t zone);
477
478/*
479 * Sets a warning to be printed when limit is reached
480 *
481 * Arguments:
482 * zone The zone we will warn about
483 * warning Warning content
484 *
485 * Returns:
486 * Nothing
487 */
488void uma_zone_set_warning(uma_zone_t zone, const char *warning);
489
490/*
491 * Obtains the approximate current number of items allocated from a zone
492 *
493 * Arguments:
494 * zone The zone to obtain the current allocation count from
495 *
496 * Return:
497 * int The approximate current number of items allocated from the zone
498 */
499int uma_zone_get_cur(uma_zone_t zone);
500
501/*
502 * The following two routines (uma_zone_set_init/fini)
503 * are used to set the backend init/fini pair which acts on an
504 * object as it becomes allocated and is placed in a slab within
505 * the specified zone's backing keg. These should probably not
506 * be changed once allocations have already begun, but only be set
507 * immediately upon zone creation.
508 */
509void uma_zone_set_init(uma_zone_t zone, uma_init uminit);
510void uma_zone_set_fini(uma_zone_t zone, uma_fini fini);
511
512/*
513 * The following two routines (uma_zone_set_zinit/zfini) are
514 * used to set the zinit/zfini pair which acts on an object as
515 * it passes from the backing Keg's slab cache to the
516 * specified Zone's bucket cache. These should probably not
517 * be changed once allocations have already begun, but only be set
518 * immediately upon zone creation.
519 */
520void uma_zone_set_zinit(uma_zone_t zone, uma_init zinit);
521void uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini);
522
523/*
524 * Replaces the standard page_alloc or obj_alloc functions for this zone
525 *
526 * Arguments:
527 * zone The zone whose backend allocator is being changed.
528 * allocf A pointer to the allocation function
529 *
530 * Returns:
531 * Nothing
532 *
533 * Discussion:
534 * This could be used to implement pageable allocation, or perhaps
535 * even DMA allocators if used in conjunction with the OFFPAGE
536 * zone flag.
537 */
538
539void uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf);
540
541/*
542 * Used for freeing memory provided by the allocf above
543 *
544 * Arguments:
545 * zone The zone that intends to use this free routine.
546 * freef The page freeing routine.
547 *
548 * Returns:
549 * Nothing
550 */
551
552void uma_zone_set_freef(uma_zone_t zone, uma_free freef);
553
554/*
555 * These flags are setable in the allocf and visible in the freef.
556 */
557#define UMA_SLAB_BOOT 0x01 /* Slab alloced from boot pages */
558#define UMA_SLAB_KMEM 0x02 /* Slab alloced from kmem_map */
559#define UMA_SLAB_KERNEL 0x04 /* Slab alloced from kernel_map */
560#define UMA_SLAB_PRIV 0x08 /* Slab alloced from priv allocator */
561#define UMA_SLAB_OFFP 0x10 /* Slab is managed separately */
562#define UMA_SLAB_MALLOC 0x20 /* Slab is a large malloc slab */
563/* 0x40 and 0x80 are available */
564
565/*
566 * Used to pre-fill a zone with some number of items
567 *
568 * Arguments:
569 * zone The zone to fill
570 * itemcnt The number of items to reserve
571 *
572 * Returns:
573 * Nothing
574 *
575 * NOTE: This is blocking and should only be done at startup
576 */
577void uma_prealloc(uma_zone_t zone, int itemcnt);
578
579/*
580 * Used to lookup the reference counter allocated for an item
581 * from a UMA_ZONE_REFCNT zone. For UMA_ZONE_REFCNT zones,
582 * reference counters are allocated for items and stored in
583 * the underlying slab header.
584 *
585 * Arguments:
586 * zone The UMA_ZONE_REFCNT zone to which the item belongs.
587 * item The address of the item for which we want a refcnt.
588 *
589 * Returns:
590 * A pointer to a u_int32_t reference counter.
591 */
592u_int32_t *uma_find_refcnt(uma_zone_t zone, void *item);
593
594/*
595 * Used to determine if a fixed-size zone is exhausted.
596 *
597 * Arguments:
598 * zone The zone to check
599 *
600 * Returns:
601 * Non-zero if zone is exhausted.
602 */
603int uma_zone_exhausted(uma_zone_t zone);
604int uma_zone_exhausted_nolock(uma_zone_t zone);
605
606/*
607 * Exported statistics structures to be used by user space monitoring tools.
608 * Statistics stream consists of a uma_stream_header, followed by a series of
609 * alternative uma_type_header and uma_type_stat structures.
610 */
611#define UMA_STREAM_VERSION 0x00000001
612struct uma_stream_header {
613 u_int32_t ush_version; /* Stream format version. */
614 u_int32_t ush_maxcpus; /* Value of MAXCPU for stream. */
615 u_int32_t ush_count; /* Number of records. */
616 u_int32_t _ush_pad; /* Pad/reserved field. */
617};
618
619#define UTH_MAX_NAME 32
620#define UTH_ZONE_SECONDARY 0x00000001
621struct uma_type_header {
622 /*
623 * Static per-zone data, some extracted from the supporting keg.
624 */
625 char uth_name[UTH_MAX_NAME];
626 u_int32_t uth_align; /* Keg: alignment. */
627 u_int32_t uth_size; /* Keg: requested size of item. */
628 u_int32_t uth_rsize; /* Keg: real size of item. */
629 u_int32_t uth_maxpages; /* Keg: maximum number of pages. */
630 u_int32_t uth_limit; /* Keg: max items to allocate. */
631
632 /*
633 * Current dynamic zone/keg-derived statistics.
634 */
635 u_int32_t uth_pages; /* Keg: pages allocated. */
636 u_int32_t uth_keg_free; /* Keg: items free. */
637 u_int32_t uth_zone_free; /* Zone: items free. */
638 u_int32_t uth_bucketsize; /* Zone: desired bucket size. */
639 u_int32_t uth_zone_flags; /* Zone: flags. */
640 u_int64_t uth_allocs; /* Zone: number of allocations. */
641 u_int64_t uth_frees; /* Zone: number of frees. */
642 u_int64_t uth_fails; /* Zone: number of alloc failures. */
643 u_int64_t uth_sleeps; /* Zone: number of alloc sleeps. */
644 u_int64_t _uth_reserved1[2]; /* Reserved. */
645};
646
647struct uma_percpu_stat {
648 u_int64_t ups_allocs; /* Cache: number of allocations. */
649 u_int64_t ups_frees; /* Cache: number of frees. */
650 u_int64_t ups_cache_free; /* Cache: free items in cache. */
651 u_int64_t _ups_reserved[5]; /* Reserved. */
652};
653
654#endif
2 * Copyright (c) 2002, 2003, 2004, 2005 Jeffrey Roberson <jeff@FreeBSD.org>
3 * Copyright (c) 2004, 2005 Bosko Milekic <bmilekic@FreeBSD.org>
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice unmodified, this list of conditions, and the following
11 * disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 *
27 * $FreeBSD: head/sys/vm/uma.h 244024 2012-12-08 09:23:05Z pjd $
28 *
29 */
30
31/*
32 * uma.h - External definitions for the Universal Memory Allocator
33 *
34*/
35
36#ifndef VM_UMA_H
37#define VM_UMA_H
38
39#include <sys/param.h> /* For NULL */
40#include <sys/malloc.h> /* For M_* */
41
42/* User visible parameters */
43#define UMA_SMALLEST_UNIT (PAGE_SIZE / 256) /* Smallest item allocated */
44
45/* Types and type defs */
46
47struct uma_zone;
48/* Opaque type used as a handle to the zone */
49typedef struct uma_zone * uma_zone_t;
50
51void zone_drain(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 */
70typedef 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 */
88typedef 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 */
107typedef 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 */
124typedef void (*uma_fini)(void *mem, int size);
125
126/*
127 * What's the difference between initializing and constructing?
128 *
129 * The item is initialized when it is cached, and this is the state that the
130 * object should be in when returned to the allocator. The purpose of this is
131 * to remove some code which would otherwise be called on each allocation by
132 * utilizing a known, stable state. This differs from the constructor which
133 * will be called on EVERY allocation.
134 *
135 * For example, in the initializer you may want to initialize embedded locks,
136 * NULL list pointers, set up initial states, magic numbers, etc. This way if
137 * the object is held in the allocator and re-used it won't be necessary to
138 * re-initialize it.
139 *
140 * The constructor may be used to lock a data structure, link it on to lists,
141 * bump reference counts or total counts of outstanding structures, etc.
142 *
143 */
144
145
146/* Function proto types */
147
148/*
149 * Create a new uma zone
150 *
151 * Arguments:
152 * name The text name of the zone for debugging and stats. This memory
153 * should not be freed until the zone has been deallocated.
154 * size The size of the object that is being created.
155 * ctor The constructor that is called when the object is allocated.
156 * dtor The destructor that is called when the object is freed.
157 * init An initializer that sets up the initial state of the memory.
158 * fini A discard function that undoes initialization done by init.
159 * ctor/dtor/init/fini may all be null, see notes above.
160 * align A bitmask that corresponds to the requested alignment
161 * eg 4 would be 0x3
162 * flags A set of parameters that control the behavior of the zone.
163 *
164 * Returns:
165 * A pointer to a structure which is intended to be opaque to users of
166 * the interface. The value may be null if the wait flag is not set.
167 */
168uma_zone_t uma_zcreate(const char *name, size_t size, uma_ctor ctor,
169 uma_dtor dtor, uma_init uminit, uma_fini fini,
170 int align, u_int32_t flags);
171
172/*
173 * Create a secondary uma zone
174 *
175 * Arguments:
176 * name The text name of the zone for debugging and stats. This memory
177 * should not be freed until the zone has been deallocated.
178 * ctor The constructor that is called when the object is allocated.
179 * dtor The destructor that is called when the object is freed.
180 * zinit An initializer that sets up the initial state of the memory
181 * as the object passes from the Keg's slab to the Zone's cache.
182 * zfini A discard function that undoes initialization done by init
183 * as the object passes from the Zone's cache to the Keg's slab.
184 *
185 * ctor/dtor/zinit/zfini may all be null, see notes above.
186 * Note that the zinit and zfini specified here are NOT
187 * exactly the same as the init/fini specified to uma_zcreate()
188 * when creating a master zone. These zinit/zfini are called
189 * on the TRANSITION from keg to zone (and vice-versa). Once
190 * these are set, the primary zone may alter its init/fini
191 * (which are called when the object passes from VM to keg)
192 * using uma_zone_set_init/fini()) as well as its own
193 * zinit/zfini (unset by default for master zone) with
194 * uma_zone_set_zinit/zfini() (note subtle 'z' prefix).
195 *
196 * master A reference to this zone's Master Zone (Primary Zone),
197 * which contains the backing Keg for the Secondary Zone
198 * being added.
199 *
200 * Returns:
201 * A pointer to a structure which is intended to be opaque to users of
202 * the interface. The value may be null if the wait flag is not set.
203 */
204uma_zone_t uma_zsecond_create(char *name, uma_ctor ctor, uma_dtor dtor,
205 uma_init zinit, uma_fini zfini, uma_zone_t master);
206
207/*
208 * Add a second master to a secondary zone. This provides multiple data
209 * backends for objects with the same size. Both masters must have
210 * compatible allocation flags. Presently, UMA_ZONE_MALLOC type zones are
211 * the only supported.
212 *
213 * Returns:
214 * Error on failure, 0 on success.
215 */
216int uma_zsecond_add(uma_zone_t zone, uma_zone_t master);
217
218/*
219 * Definitions for uma_zcreate flags
220 *
221 * These flags share space with UMA_ZFLAGs in uma_int.h. Be careful not to
222 * overlap when adding new features. 0xf0000000 is in use by uma_int.h.
223 */
224#define UMA_ZONE_PAGEABLE 0x0001 /* Return items not fully backed by
225 physical memory XXX Not yet */
226#define UMA_ZONE_ZINIT 0x0002 /* Initialize with zeros */
227#define UMA_ZONE_STATIC 0x0004 /* Statically sized zone */
228#define UMA_ZONE_OFFPAGE 0x0008 /* Force the slab structure allocation
229 off of the real memory */
230#define UMA_ZONE_MALLOC 0x0010 /* For use by malloc(9) only! */
231#define UMA_ZONE_NOFREE 0x0020 /* Do not free slabs of this type! */
232#define UMA_ZONE_MTXCLASS 0x0040 /* Create a new lock class */
233#define UMA_ZONE_VM 0x0080 /*
234 * Used for internal vm datastructures
235 * only.
236 */
237#define UMA_ZONE_HASH 0x0100 /*
238 * Use a hash table instead of caching
239 * information in the vm_page.
240 */
241#define UMA_ZONE_SECONDARY 0x0200 /* Zone is a Secondary Zone */
242#define UMA_ZONE_REFCNT 0x0400 /* Allocate refcnts in slabs */
243#define UMA_ZONE_MAXBUCKET 0x0800 /* Use largest buckets */
244#define UMA_ZONE_CACHESPREAD 0x1000 /*
245 * Spread memory start locations across
246 * all possible cache lines. May
247 * require many virtually contiguous
248 * backend pages and can fail early.
249 */
250#define UMA_ZONE_VTOSLAB 0x2000 /* Zone uses vtoslab for lookup. */
251#define UMA_ZONE_NODUMP 0x4000 /*
252 * Zone's pages will not be included in
253 * mini-dumps.
254 */
255
256/*
257 * These flags are shared between the keg and zone. In zones wishing to add
258 * new kegs these flags must be compatible. Some are determined based on
259 * physical parameters of the request and may not be provided by the consumer.
260 */
261#define UMA_ZONE_INHERIT \
262 (UMA_ZONE_OFFPAGE | UMA_ZONE_MALLOC | UMA_ZONE_NOFREE | \
263 UMA_ZONE_HASH | UMA_ZONE_REFCNT | UMA_ZONE_VTOSLAB)
264
265/* Definitions for align */
266#define UMA_ALIGN_PTR (sizeof(void *) - 1) /* Alignment fit for ptr */
267#define UMA_ALIGN_LONG (sizeof(long) - 1) /* "" long */
268#define UMA_ALIGN_INT (sizeof(int) - 1) /* "" int */
269#define UMA_ALIGN_SHORT (sizeof(short) - 1) /* "" short */
270#define UMA_ALIGN_CHAR (sizeof(char) - 1) /* "" char */
271#define UMA_ALIGN_CACHE (0 - 1) /* Cache line size align */
272
273/*
274 * Destroys an empty uma zone. If the zone is not empty uma complains loudly.
275 *
276 * Arguments:
277 * zone The zone we want to destroy.
278 *
279 */
280void uma_zdestroy(uma_zone_t zone);
281
282/*
283 * Allocates an item out of a zone
284 *
285 * Arguments:
286 * zone The zone we are allocating from
287 * arg This data is passed to the ctor function
288 * flags See sys/malloc.h for available flags.
289 *
290 * Returns:
291 * A non-null pointer to an initialized element from the zone is
292 * guaranteed if the wait flag is M_WAITOK. Otherwise a null pointer
293 * may be returned if the zone is empty or the ctor failed.
294 */
295
296void *uma_zalloc_arg(uma_zone_t zone, void *arg, int flags);
297
298/*
299 * Allocates an item out of a zone without supplying an argument
300 *
301 * This is just a wrapper for uma_zalloc_arg for convenience.
302 *
303 */
304static __inline void *uma_zalloc(uma_zone_t zone, int flags);
305
306static __inline void *
307uma_zalloc(uma_zone_t zone, int flags)
308{
309 return uma_zalloc_arg(zone, NULL, flags);
310}
311
312/*
313 * Frees an item back into the specified zone.
314 *
315 * Arguments:
316 * zone The zone the item was originally allocated out of.
317 * item The memory to be freed.
318 * arg Argument passed to the destructor
319 *
320 * Returns:
321 * Nothing.
322 */
323
324void uma_zfree_arg(uma_zone_t zone, void *item, void *arg);
325
326/*
327 * Frees an item back to a zone without supplying an argument
328 *
329 * This is just a wrapper for uma_zfree_arg for convenience.
330 *
331 */
332static __inline void uma_zfree(uma_zone_t zone, void *item);
333
334static __inline void
335uma_zfree(uma_zone_t zone, void *item)
336{
337 uma_zfree_arg(zone, item, NULL);
338}
339
340/*
341 * XXX The rest of the prototypes in this header are h0h0 magic for the VM.
342 * If you think you need to use it for a normal zone you're probably incorrect.
343 */
344
345/*
346 * Backend page supplier routines
347 *
348 * Arguments:
349 * zone The zone that is requesting pages.
350 * size The number of bytes being requested.
351 * pflag Flags for these memory pages, see below.
352 * wait Indicates our willingness to block.
353 *
354 * Returns:
355 * A pointer to the allocated memory or NULL on failure.
356 */
357
358typedef void *(*uma_alloc)(uma_zone_t zone, int size, u_int8_t *pflag, int wait);
359
360/*
361 * Backend page free routines
362 *
363 * Arguments:
364 * item A pointer to the previously allocated pages.
365 * size The original size of the allocation.
366 * pflag The flags for the slab. See UMA_SLAB_* below.
367 *
368 * Returns:
369 * None
370 */
371typedef void (*uma_free)(void *item, int size, u_int8_t pflag);
372
373
374
375/*
376 * Sets up the uma allocator. (Called by vm_mem_init)
377 *
378 * Arguments:
379 * bootmem A pointer to memory used to bootstrap the system.
380 *
381 * Returns:
382 * Nothing
383 *
384 * Discussion:
385 * This memory is used for zones which allocate things before the
386 * backend page supplier can give us pages. It should be
387 * UMA_SLAB_SIZE * boot_pages bytes. (see uma_int.h)
388 *
389 */
390
391void uma_startup(void *bootmem, int boot_pages);
392
393/*
394 * Finishes starting up the allocator. This should
395 * be called when kva is ready for normal allocs.
396 *
397 * Arguments:
398 * None
399 *
400 * Returns:
401 * Nothing
402 *
403 * Discussion:
404 * uma_startup2 is called by kmeminit() to enable us of uma for malloc.
405 */
406
407void uma_startup2(void);
408
409/*
410 * Reclaims unused memory for all zones
411 *
412 * Arguments:
413 * None
414 * Returns:
415 * None
416 *
417 * This should only be called by the page out daemon.
418 */
419
420void uma_reclaim(void);
421
422/*
423 * Sets the alignment mask to be used for all zones requesting cache
424 * alignment. Should be called by MD boot code prior to starting VM/UMA.
425 *
426 * Arguments:
427 * align The alignment mask
428 *
429 * Returns:
430 * Nothing
431 */
432void uma_set_align(int align);
433
434/*
435 * Switches the backing object of a zone
436 *
437 * Arguments:
438 * zone The zone to update.
439 * obj The VM object to use for future allocations.
440 * size The size of the object to allocate.
441 *
442 * Returns:
443 * 0 if kva space can not be allocated
444 * 1 if successful
445 *
446 * Discussion:
447 * A NULL object can be used and uma will allocate one for you. Setting
448 * the size will limit the amount of memory allocated to this zone.
449 *
450 */
451struct vm_object;
452int uma_zone_set_obj(uma_zone_t zone, struct vm_object *obj, int size);
453
454/*
455 * Sets a high limit on the number of items allowed in a zone
456 *
457 * Arguments:
458 * zone The zone to limit
459 * nitems The requested upper limit on the number of items allowed
460 *
461 * Returns:
462 * int The effective value of nitems after rounding up based on page size
463 */
464int uma_zone_set_max(uma_zone_t zone, int nitems);
465
466/*
467 * Obtains the effective limit on the number of items in a zone
468 *
469 * Arguments:
470 * zone The zone to obtain the effective limit from
471 *
472 * Return:
473 * 0 No limit
474 * int The effective limit of the zone
475 */
476int uma_zone_get_max(uma_zone_t zone);
477
478/*
479 * Sets a warning to be printed when limit is reached
480 *
481 * Arguments:
482 * zone The zone we will warn about
483 * warning Warning content
484 *
485 * Returns:
486 * Nothing
487 */
488void uma_zone_set_warning(uma_zone_t zone, const char *warning);
489
490/*
491 * Obtains the approximate current number of items allocated from a zone
492 *
493 * Arguments:
494 * zone The zone to obtain the current allocation count from
495 *
496 * Return:
497 * int The approximate current number of items allocated from the zone
498 */
499int uma_zone_get_cur(uma_zone_t zone);
500
501/*
502 * The following two routines (uma_zone_set_init/fini)
503 * are used to set the backend init/fini pair which acts on an
504 * object as it becomes allocated and is placed in a slab within
505 * the specified zone's backing keg. These should probably not
506 * be changed once allocations have already begun, but only be set
507 * immediately upon zone creation.
508 */
509void uma_zone_set_init(uma_zone_t zone, uma_init uminit);
510void uma_zone_set_fini(uma_zone_t zone, uma_fini fini);
511
512/*
513 * The following two routines (uma_zone_set_zinit/zfini) are
514 * used to set the zinit/zfini pair which acts on an object as
515 * it passes from the backing Keg's slab cache to the
516 * specified Zone's bucket cache. These should probably not
517 * be changed once allocations have already begun, but only be set
518 * immediately upon zone creation.
519 */
520void uma_zone_set_zinit(uma_zone_t zone, uma_init zinit);
521void uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini);
522
523/*
524 * Replaces the standard page_alloc or obj_alloc functions for this zone
525 *
526 * Arguments:
527 * zone The zone whose backend allocator is being changed.
528 * allocf A pointer to the allocation function
529 *
530 * Returns:
531 * Nothing
532 *
533 * Discussion:
534 * This could be used to implement pageable allocation, or perhaps
535 * even DMA allocators if used in conjunction with the OFFPAGE
536 * zone flag.
537 */
538
539void uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf);
540
541/*
542 * Used for freeing memory provided by the allocf above
543 *
544 * Arguments:
545 * zone The zone that intends to use this free routine.
546 * freef The page freeing routine.
547 *
548 * Returns:
549 * Nothing
550 */
551
552void uma_zone_set_freef(uma_zone_t zone, uma_free freef);
553
554/*
555 * These flags are setable in the allocf and visible in the freef.
556 */
557#define UMA_SLAB_BOOT 0x01 /* Slab alloced from boot pages */
558#define UMA_SLAB_KMEM 0x02 /* Slab alloced from kmem_map */
559#define UMA_SLAB_KERNEL 0x04 /* Slab alloced from kernel_map */
560#define UMA_SLAB_PRIV 0x08 /* Slab alloced from priv allocator */
561#define UMA_SLAB_OFFP 0x10 /* Slab is managed separately */
562#define UMA_SLAB_MALLOC 0x20 /* Slab is a large malloc slab */
563/* 0x40 and 0x80 are available */
564
565/*
566 * Used to pre-fill a zone with some number of items
567 *
568 * Arguments:
569 * zone The zone to fill
570 * itemcnt The number of items to reserve
571 *
572 * Returns:
573 * Nothing
574 *
575 * NOTE: This is blocking and should only be done at startup
576 */
577void uma_prealloc(uma_zone_t zone, int itemcnt);
578
579/*
580 * Used to lookup the reference counter allocated for an item
581 * from a UMA_ZONE_REFCNT zone. For UMA_ZONE_REFCNT zones,
582 * reference counters are allocated for items and stored in
583 * the underlying slab header.
584 *
585 * Arguments:
586 * zone The UMA_ZONE_REFCNT zone to which the item belongs.
587 * item The address of the item for which we want a refcnt.
588 *
589 * Returns:
590 * A pointer to a u_int32_t reference counter.
591 */
592u_int32_t *uma_find_refcnt(uma_zone_t zone, void *item);
593
594/*
595 * Used to determine if a fixed-size zone is exhausted.
596 *
597 * Arguments:
598 * zone The zone to check
599 *
600 * Returns:
601 * Non-zero if zone is exhausted.
602 */
603int uma_zone_exhausted(uma_zone_t zone);
604int uma_zone_exhausted_nolock(uma_zone_t zone);
605
606/*
607 * Exported statistics structures to be used by user space monitoring tools.
608 * Statistics stream consists of a uma_stream_header, followed by a series of
609 * alternative uma_type_header and uma_type_stat structures.
610 */
611#define UMA_STREAM_VERSION 0x00000001
612struct uma_stream_header {
613 u_int32_t ush_version; /* Stream format version. */
614 u_int32_t ush_maxcpus; /* Value of MAXCPU for stream. */
615 u_int32_t ush_count; /* Number of records. */
616 u_int32_t _ush_pad; /* Pad/reserved field. */
617};
618
619#define UTH_MAX_NAME 32
620#define UTH_ZONE_SECONDARY 0x00000001
621struct uma_type_header {
622 /*
623 * Static per-zone data, some extracted from the supporting keg.
624 */
625 char uth_name[UTH_MAX_NAME];
626 u_int32_t uth_align; /* Keg: alignment. */
627 u_int32_t uth_size; /* Keg: requested size of item. */
628 u_int32_t uth_rsize; /* Keg: real size of item. */
629 u_int32_t uth_maxpages; /* Keg: maximum number of pages. */
630 u_int32_t uth_limit; /* Keg: max items to allocate. */
631
632 /*
633 * Current dynamic zone/keg-derived statistics.
634 */
635 u_int32_t uth_pages; /* Keg: pages allocated. */
636 u_int32_t uth_keg_free; /* Keg: items free. */
637 u_int32_t uth_zone_free; /* Zone: items free. */
638 u_int32_t uth_bucketsize; /* Zone: desired bucket size. */
639 u_int32_t uth_zone_flags; /* Zone: flags. */
640 u_int64_t uth_allocs; /* Zone: number of allocations. */
641 u_int64_t uth_frees; /* Zone: number of frees. */
642 u_int64_t uth_fails; /* Zone: number of alloc failures. */
643 u_int64_t uth_sleeps; /* Zone: number of alloc sleeps. */
644 u_int64_t _uth_reserved1[2]; /* Reserved. */
645};
646
647struct uma_percpu_stat {
648 u_int64_t ups_allocs; /* Cache: number of allocations. */
649 u_int64_t ups_frees; /* Cache: number of frees. */
650 u_int64_t ups_cache_free; /* Cache: free items in cache. */
651 u_int64_t _ups_reserved[5]; /* Reserved. */
652};
653
654#endif