xref: /freebsd/sys/vm/uma_core.c (revision 87c1627502a5dde91e5284118eec8682b60f27a2)
1 /*-
2  * Copyright (c) 2002-2005, 2009 Jeffrey Roberson <jeff@FreeBSD.org>
3  * Copyright (c) 2004, 2005 Bosko Milekic <bmilekic@FreeBSD.org>
4  * Copyright (c) 2004-2006 Robert N. M. Watson
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice unmodified, this list of conditions, and the following
12  *    disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 /*
30  * uma_core.c  Implementation of the Universal Memory allocator
31  *
32  * This allocator is intended to replace the multitude of similar object caches
33  * in the standard FreeBSD kernel.  The intent is to be flexible as well as
34  * effecient.  A primary design goal is to return unused memory to the rest of
35  * the system.  This will make the system as a whole more flexible due to the
36  * ability to move memory to subsystems which most need it instead of leaving
37  * pools of reserved memory unused.
38  *
39  * The basic ideas stem from similar slab/zone based allocators whose algorithms
40  * are well known.
41  *
42  */
43 
44 /*
45  * TODO:
46  *	- Improve memory usage for large allocations
47  *	- Investigate cache size adjustments
48  */
49 
50 #include <sys/cdefs.h>
51 __FBSDID("$FreeBSD$");
52 
53 /* I should really use ktr.. */
54 /*
55 #define UMA_DEBUG 1
56 #define UMA_DEBUG_ALLOC 1
57 #define UMA_DEBUG_ALLOC_1 1
58 */
59 
60 #include "opt_ddb.h"
61 #include "opt_param.h"
62 #include "opt_vm.h"
63 
64 #include <sys/param.h>
65 #include <sys/systm.h>
66 #include <sys/kernel.h>
67 #include <sys/types.h>
68 #include <sys/queue.h>
69 #include <sys/malloc.h>
70 #include <sys/ktr.h>
71 #include <sys/lock.h>
72 #include <sys/sysctl.h>
73 #include <sys/mutex.h>
74 #include <sys/proc.h>
75 #include <sys/rwlock.h>
76 #include <sys/sbuf.h>
77 #include <sys/smp.h>
78 #include <sys/vmmeter.h>
79 
80 #include <vm/vm.h>
81 #include <vm/vm_object.h>
82 #include <vm/vm_page.h>
83 #include <vm/vm_pageout.h>
84 #include <vm/vm_param.h>
85 #include <vm/vm_map.h>
86 #include <vm/vm_kern.h>
87 #include <vm/vm_extern.h>
88 #include <vm/uma.h>
89 #include <vm/uma_int.h>
90 #include <vm/uma_dbg.h>
91 
92 #include <ddb/ddb.h>
93 
94 #ifdef DEBUG_MEMGUARD
95 #include <vm/memguard.h>
96 #endif
97 
98 /*
99  * This is the zone and keg from which all zones are spawned.  The idea is that
100  * even the zone & keg heads are allocated from the allocator, so we use the
101  * bss section to bootstrap us.
102  */
103 static struct uma_keg masterkeg;
104 static struct uma_zone masterzone_k;
105 static struct uma_zone masterzone_z;
106 static uma_zone_t kegs = &masterzone_k;
107 static uma_zone_t zones = &masterzone_z;
108 
109 /* This is the zone from which all of uma_slab_t's are allocated. */
110 static uma_zone_t slabzone;
111 static uma_zone_t slabrefzone;	/* With refcounters (for UMA_ZONE_REFCNT) */
112 
113 /*
114  * The initial hash tables come out of this zone so they can be allocated
115  * prior to malloc coming up.
116  */
117 static uma_zone_t hashzone;
118 
119 /* The boot-time adjusted value for cache line alignment. */
120 int uma_align_cache = 64 - 1;
121 
122 static MALLOC_DEFINE(M_UMAHASH, "UMAHash", "UMA Hash Buckets");
123 
124 /*
125  * Are we allowed to allocate buckets?
126  */
127 static int bucketdisable = 1;
128 
129 /* Linked list of all kegs in the system */
130 static LIST_HEAD(,uma_keg) uma_kegs = LIST_HEAD_INITIALIZER(uma_kegs);
131 
132 /* This mutex protects the keg list */
133 static struct mtx uma_mtx;
134 
135 /* Linked list of boot time pages */
136 static LIST_HEAD(,uma_slab) uma_boot_pages =
137     LIST_HEAD_INITIALIZER(uma_boot_pages);
138 
139 /* This mutex protects the boot time pages list */
140 static struct mtx uma_boot_pages_mtx;
141 
142 /* Is the VM done starting up? */
143 static int booted = 0;
144 #define	UMA_STARTUP	1
145 #define	UMA_STARTUP2	2
146 
147 /* Maximum number of allowed items-per-slab if the slab header is OFFPAGE */
148 static u_int uma_max_ipers;
149 static u_int uma_max_ipers_ref;
150 
151 /*
152  * This is the handle used to schedule events that need to happen
153  * outside of the allocation fast path.
154  */
155 static struct callout uma_callout;
156 #define	UMA_TIMEOUT	20		/* Seconds for callout interval. */
157 
158 /*
159  * This structure is passed as the zone ctor arg so that I don't have to create
160  * a special allocation function just for zones.
161  */
162 struct uma_zctor_args {
163 	const char *name;
164 	size_t size;
165 	uma_ctor ctor;
166 	uma_dtor dtor;
167 	uma_init uminit;
168 	uma_fini fini;
169 	uma_keg_t keg;
170 	int align;
171 	uint32_t flags;
172 };
173 
174 struct uma_kctor_args {
175 	uma_zone_t zone;
176 	size_t size;
177 	uma_init uminit;
178 	uma_fini fini;
179 	int align;
180 	uint32_t flags;
181 };
182 
183 struct uma_bucket_zone {
184 	uma_zone_t	ubz_zone;
185 	char		*ubz_name;
186 	int		ubz_entries;
187 };
188 
189 #define	BUCKET_MAX	128
190 
191 struct uma_bucket_zone bucket_zones[] = {
192 	{ NULL, "16 Bucket", 16 },
193 	{ NULL, "32 Bucket", 32 },
194 	{ NULL, "64 Bucket", 64 },
195 	{ NULL, "128 Bucket", 128 },
196 	{ NULL, NULL, 0}
197 };
198 
199 #define	BUCKET_SHIFT	4
200 #define	BUCKET_ZONES	((BUCKET_MAX >> BUCKET_SHIFT) + 1)
201 
202 /*
203  * bucket_size[] maps requested bucket sizes to zones that allocate a bucket
204  * of approximately the right size.
205  */
206 static uint8_t bucket_size[BUCKET_ZONES];
207 
208 /*
209  * Flags and enumerations to be passed to internal functions.
210  */
211 enum zfreeskip { SKIP_NONE, SKIP_DTOR, SKIP_FINI };
212 
213 #define	ZFREE_STATFAIL	0x00000001	/* Update zone failure statistic. */
214 #define	ZFREE_STATFREE	0x00000002	/* Update zone free statistic. */
215 
216 /* Prototypes.. */
217 
218 static void *noobj_alloc(uma_zone_t, int, uint8_t *, int);
219 static void *page_alloc(uma_zone_t, int, uint8_t *, int);
220 static void *startup_alloc(uma_zone_t, int, uint8_t *, int);
221 static void page_free(void *, int, uint8_t);
222 static uma_slab_t keg_alloc_slab(uma_keg_t, uma_zone_t, int);
223 static void cache_drain(uma_zone_t);
224 static void bucket_drain(uma_zone_t, uma_bucket_t);
225 static void bucket_cache_drain(uma_zone_t zone);
226 static int keg_ctor(void *, int, void *, int);
227 static void keg_dtor(void *, int, void *);
228 static int zone_ctor(void *, int, void *, int);
229 static void zone_dtor(void *, int, void *);
230 static int zero_init(void *, int, int);
231 static void keg_small_init(uma_keg_t keg);
232 static void keg_large_init(uma_keg_t keg);
233 static void zone_foreach(void (*zfunc)(uma_zone_t));
234 static void zone_timeout(uma_zone_t zone);
235 static int hash_alloc(struct uma_hash *);
236 static int hash_expand(struct uma_hash *, struct uma_hash *);
237 static void hash_free(struct uma_hash *hash);
238 static void uma_timeout(void *);
239 static void uma_startup3(void);
240 static void *zone_alloc_item(uma_zone_t, void *, int);
241 static void zone_free_item(uma_zone_t, void *, void *, enum zfreeskip,
242     int);
243 static void bucket_enable(void);
244 static void bucket_init(void);
245 static uma_bucket_t bucket_alloc(int, int);
246 static void bucket_free(uma_bucket_t);
247 static void bucket_zone_drain(void);
248 static int zone_alloc_bucket(uma_zone_t zone, int flags);
249 static uma_slab_t zone_fetch_slab(uma_zone_t zone, uma_keg_t last, int flags);
250 static uma_slab_t zone_fetch_slab_multi(uma_zone_t zone, uma_keg_t last, int flags);
251 static void *slab_alloc_item(uma_zone_t zone, uma_slab_t slab);
252 static uma_keg_t uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit,
253     uma_fini fini, int align, uint32_t flags);
254 static inline void zone_relock(uma_zone_t zone, uma_keg_t keg);
255 static inline void keg_relock(uma_keg_t keg, uma_zone_t zone);
256 
257 void uma_print_zone(uma_zone_t);
258 void uma_print_stats(void);
259 static int sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS);
260 static int sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS);
261 
262 SYSINIT(uma_startup3, SI_SUB_VM_CONF, SI_ORDER_SECOND, uma_startup3, NULL);
263 
264 SYSCTL_PROC(_vm, OID_AUTO, zone_count, CTLFLAG_RD|CTLTYPE_INT,
265     0, 0, sysctl_vm_zone_count, "I", "Number of UMA zones");
266 
267 SYSCTL_PROC(_vm, OID_AUTO, zone_stats, CTLFLAG_RD|CTLTYPE_STRUCT,
268     0, 0, sysctl_vm_zone_stats, "s,struct uma_type_header", "Zone Stats");
269 
270 static int zone_warnings = 1;
271 TUNABLE_INT("vm.zone_warnings", &zone_warnings);
272 SYSCTL_INT(_vm, OID_AUTO, zone_warnings, CTLFLAG_RW, &zone_warnings, 0,
273     "Warn when UMA zones becomes full");
274 
275 /*
276  * This routine checks to see whether or not it's safe to enable buckets.
277  */
278 
279 static void
280 bucket_enable(void)
281 {
282 	bucketdisable = vm_page_count_min();
283 }
284 
285 /*
286  * Initialize bucket_zones, the array of zones of buckets of various sizes.
287  *
288  * For each zone, calculate the memory required for each bucket, consisting
289  * of the header and an array of pointers.  Initialize bucket_size[] to point
290  * the range of appropriate bucket sizes at the zone.
291  */
292 static void
293 bucket_init(void)
294 {
295 	struct uma_bucket_zone *ubz;
296 	int i;
297 	int j;
298 
299 	for (i = 0, j = 0; bucket_zones[j].ubz_entries != 0; j++) {
300 		int size;
301 
302 		ubz = &bucket_zones[j];
303 		size = roundup(sizeof(struct uma_bucket), sizeof(void *));
304 		size += sizeof(void *) * ubz->ubz_entries;
305 		ubz->ubz_zone = uma_zcreate(ubz->ubz_name, size,
306 		    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR,
307 		    UMA_ZFLAG_INTERNAL | UMA_ZFLAG_BUCKET);
308 		for (; i <= ubz->ubz_entries; i += (1 << BUCKET_SHIFT))
309 			bucket_size[i >> BUCKET_SHIFT] = j;
310 	}
311 }
312 
313 /*
314  * Given a desired number of entries for a bucket, return the zone from which
315  * to allocate the bucket.
316  */
317 static struct uma_bucket_zone *
318 bucket_zone_lookup(int entries)
319 {
320 	int idx;
321 
322 	idx = howmany(entries, 1 << BUCKET_SHIFT);
323 	return (&bucket_zones[bucket_size[idx]]);
324 }
325 
326 static uma_bucket_t
327 bucket_alloc(int entries, int bflags)
328 {
329 	struct uma_bucket_zone *ubz;
330 	uma_bucket_t bucket;
331 
332 	/*
333 	 * This is to stop us from allocating per cpu buckets while we're
334 	 * running out of vm.boot_pages.  Otherwise, we would exhaust the
335 	 * boot pages.  This also prevents us from allocating buckets in
336 	 * low memory situations.
337 	 */
338 	if (bucketdisable)
339 		return (NULL);
340 
341 	ubz = bucket_zone_lookup(entries);
342 	bucket = zone_alloc_item(ubz->ubz_zone, NULL, bflags);
343 	if (bucket) {
344 #ifdef INVARIANTS
345 		bzero(bucket->ub_bucket, sizeof(void *) * ubz->ubz_entries);
346 #endif
347 		bucket->ub_cnt = 0;
348 		bucket->ub_entries = ubz->ubz_entries;
349 	}
350 
351 	return (bucket);
352 }
353 
354 static void
355 bucket_free(uma_bucket_t bucket)
356 {
357 	struct uma_bucket_zone *ubz;
358 
359 	ubz = bucket_zone_lookup(bucket->ub_entries);
360 	zone_free_item(ubz->ubz_zone, bucket, NULL, SKIP_NONE,
361 	    ZFREE_STATFREE);
362 }
363 
364 static void
365 bucket_zone_drain(void)
366 {
367 	struct uma_bucket_zone *ubz;
368 
369 	for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++)
370 		zone_drain(ubz->ubz_zone);
371 }
372 
373 static void
374 zone_log_warning(uma_zone_t zone)
375 {
376 	static const struct timeval warninterval = { 300, 0 };
377 
378 	if (!zone_warnings || zone->uz_warning == NULL)
379 		return;
380 
381 	if (ratecheck(&zone->uz_ratecheck, &warninterval))
382 		printf("[zone: %s] %s\n", zone->uz_name, zone->uz_warning);
383 }
384 
385 static inline uma_keg_t
386 zone_first_keg(uma_zone_t zone)
387 {
388 
389 	return (LIST_FIRST(&zone->uz_kegs)->kl_keg);
390 }
391 
392 static void
393 zone_foreach_keg(uma_zone_t zone, void (*kegfn)(uma_keg_t))
394 {
395 	uma_klink_t klink;
396 
397 	LIST_FOREACH(klink, &zone->uz_kegs, kl_link)
398 		kegfn(klink->kl_keg);
399 }
400 
401 /*
402  * Routine called by timeout which is used to fire off some time interval
403  * based calculations.  (stats, hash size, etc.)
404  *
405  * Arguments:
406  *	arg   Unused
407  *
408  * Returns:
409  *	Nothing
410  */
411 static void
412 uma_timeout(void *unused)
413 {
414 	bucket_enable();
415 	zone_foreach(zone_timeout);
416 
417 	/* Reschedule this event */
418 	callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL);
419 }
420 
421 /*
422  * Routine to perform timeout driven calculations.  This expands the
423  * hashes and does per cpu statistics aggregation.
424  *
425  *  Returns nothing.
426  */
427 static void
428 keg_timeout(uma_keg_t keg)
429 {
430 
431 	KEG_LOCK(keg);
432 	/*
433 	 * Expand the keg hash table.
434 	 *
435 	 * This is done if the number of slabs is larger than the hash size.
436 	 * What I'm trying to do here is completely reduce collisions.  This
437 	 * may be a little aggressive.  Should I allow for two collisions max?
438 	 */
439 	if (keg->uk_flags & UMA_ZONE_HASH &&
440 	    keg->uk_pages / keg->uk_ppera >= keg->uk_hash.uh_hashsize) {
441 		struct uma_hash newhash;
442 		struct uma_hash oldhash;
443 		int ret;
444 
445 		/*
446 		 * This is so involved because allocating and freeing
447 		 * while the keg lock is held will lead to deadlock.
448 		 * I have to do everything in stages and check for
449 		 * races.
450 		 */
451 		newhash = keg->uk_hash;
452 		KEG_UNLOCK(keg);
453 		ret = hash_alloc(&newhash);
454 		KEG_LOCK(keg);
455 		if (ret) {
456 			if (hash_expand(&keg->uk_hash, &newhash)) {
457 				oldhash = keg->uk_hash;
458 				keg->uk_hash = newhash;
459 			} else
460 				oldhash = newhash;
461 
462 			KEG_UNLOCK(keg);
463 			hash_free(&oldhash);
464 			KEG_LOCK(keg);
465 		}
466 	}
467 	KEG_UNLOCK(keg);
468 }
469 
470 static void
471 zone_timeout(uma_zone_t zone)
472 {
473 
474 	zone_foreach_keg(zone, &keg_timeout);
475 }
476 
477 /*
478  * Allocate and zero fill the next sized hash table from the appropriate
479  * backing store.
480  *
481  * Arguments:
482  *	hash  A new hash structure with the old hash size in uh_hashsize
483  *
484  * Returns:
485  *	1 on sucess and 0 on failure.
486  */
487 static int
488 hash_alloc(struct uma_hash *hash)
489 {
490 	int oldsize;
491 	int alloc;
492 
493 	oldsize = hash->uh_hashsize;
494 
495 	/* We're just going to go to a power of two greater */
496 	if (oldsize)  {
497 		hash->uh_hashsize = oldsize * 2;
498 		alloc = sizeof(hash->uh_slab_hash[0]) * hash->uh_hashsize;
499 		hash->uh_slab_hash = (struct slabhead *)malloc(alloc,
500 		    M_UMAHASH, M_NOWAIT);
501 	} else {
502 		alloc = sizeof(hash->uh_slab_hash[0]) * UMA_HASH_SIZE_INIT;
503 		hash->uh_slab_hash = zone_alloc_item(hashzone, NULL,
504 		    M_WAITOK);
505 		hash->uh_hashsize = UMA_HASH_SIZE_INIT;
506 	}
507 	if (hash->uh_slab_hash) {
508 		bzero(hash->uh_slab_hash, alloc);
509 		hash->uh_hashmask = hash->uh_hashsize - 1;
510 		return (1);
511 	}
512 
513 	return (0);
514 }
515 
516 /*
517  * Expands the hash table for HASH zones.  This is done from zone_timeout
518  * to reduce collisions.  This must not be done in the regular allocation
519  * path, otherwise, we can recurse on the vm while allocating pages.
520  *
521  * Arguments:
522  *	oldhash  The hash you want to expand
523  *	newhash  The hash structure for the new table
524  *
525  * Returns:
526  *	Nothing
527  *
528  * Discussion:
529  */
530 static int
531 hash_expand(struct uma_hash *oldhash, struct uma_hash *newhash)
532 {
533 	uma_slab_t slab;
534 	int hval;
535 	int i;
536 
537 	if (!newhash->uh_slab_hash)
538 		return (0);
539 
540 	if (oldhash->uh_hashsize >= newhash->uh_hashsize)
541 		return (0);
542 
543 	/*
544 	 * I need to investigate hash algorithms for resizing without a
545 	 * full rehash.
546 	 */
547 
548 	for (i = 0; i < oldhash->uh_hashsize; i++)
549 		while (!SLIST_EMPTY(&oldhash->uh_slab_hash[i])) {
550 			slab = SLIST_FIRST(&oldhash->uh_slab_hash[i]);
551 			SLIST_REMOVE_HEAD(&oldhash->uh_slab_hash[i], us_hlink);
552 			hval = UMA_HASH(newhash, slab->us_data);
553 			SLIST_INSERT_HEAD(&newhash->uh_slab_hash[hval],
554 			    slab, us_hlink);
555 		}
556 
557 	return (1);
558 }
559 
560 /*
561  * Free the hash bucket to the appropriate backing store.
562  *
563  * Arguments:
564  *	slab_hash  The hash bucket we're freeing
565  *	hashsize   The number of entries in that hash bucket
566  *
567  * Returns:
568  *	Nothing
569  */
570 static void
571 hash_free(struct uma_hash *hash)
572 {
573 	if (hash->uh_slab_hash == NULL)
574 		return;
575 	if (hash->uh_hashsize == UMA_HASH_SIZE_INIT)
576 		zone_free_item(hashzone,
577 		    hash->uh_slab_hash, NULL, SKIP_NONE, ZFREE_STATFREE);
578 	else
579 		free(hash->uh_slab_hash, M_UMAHASH);
580 }
581 
582 /*
583  * Frees all outstanding items in a bucket
584  *
585  * Arguments:
586  *	zone   The zone to free to, must be unlocked.
587  *	bucket The free/alloc bucket with items, cpu queue must be locked.
588  *
589  * Returns:
590  *	Nothing
591  */
592 
593 static void
594 bucket_drain(uma_zone_t zone, uma_bucket_t bucket)
595 {
596 	void *item;
597 
598 	if (bucket == NULL)
599 		return;
600 
601 	while (bucket->ub_cnt > 0)  {
602 		bucket->ub_cnt--;
603 		item = bucket->ub_bucket[bucket->ub_cnt];
604 #ifdef INVARIANTS
605 		bucket->ub_bucket[bucket->ub_cnt] = NULL;
606 		KASSERT(item != NULL,
607 		    ("bucket_drain: botched ptr, item is NULL"));
608 #endif
609 		zone_free_item(zone, item, NULL, SKIP_DTOR, 0);
610 	}
611 }
612 
613 /*
614  * Drains the per cpu caches for a zone.
615  *
616  * NOTE: This may only be called while the zone is being turn down, and not
617  * during normal operation.  This is necessary in order that we do not have
618  * to migrate CPUs to drain the per-CPU caches.
619  *
620  * Arguments:
621  *	zone     The zone to drain, must be unlocked.
622  *
623  * Returns:
624  *	Nothing
625  */
626 static void
627 cache_drain(uma_zone_t zone)
628 {
629 	uma_cache_t cache;
630 	int cpu;
631 
632 	/*
633 	 * XXX: It is safe to not lock the per-CPU caches, because we're
634 	 * tearing down the zone anyway.  I.e., there will be no further use
635 	 * of the caches at this point.
636 	 *
637 	 * XXX: It would good to be able to assert that the zone is being
638 	 * torn down to prevent improper use of cache_drain().
639 	 *
640 	 * XXX: We lock the zone before passing into bucket_cache_drain() as
641 	 * it is used elsewhere.  Should the tear-down path be made special
642 	 * there in some form?
643 	 */
644 	CPU_FOREACH(cpu) {
645 		cache = &zone->uz_cpu[cpu];
646 		bucket_drain(zone, cache->uc_allocbucket);
647 		bucket_drain(zone, cache->uc_freebucket);
648 		if (cache->uc_allocbucket != NULL)
649 			bucket_free(cache->uc_allocbucket);
650 		if (cache->uc_freebucket != NULL)
651 			bucket_free(cache->uc_freebucket);
652 		cache->uc_allocbucket = cache->uc_freebucket = NULL;
653 	}
654 	ZONE_LOCK(zone);
655 	bucket_cache_drain(zone);
656 	ZONE_UNLOCK(zone);
657 }
658 
659 /*
660  * Drain the cached buckets from a zone.  Expects a locked zone on entry.
661  */
662 static void
663 bucket_cache_drain(uma_zone_t zone)
664 {
665 	uma_bucket_t bucket;
666 
667 	/*
668 	 * Drain the bucket queues and free the buckets, we just keep two per
669 	 * cpu (alloc/free).
670 	 */
671 	while ((bucket = LIST_FIRST(&zone->uz_full_bucket)) != NULL) {
672 		LIST_REMOVE(bucket, ub_link);
673 		ZONE_UNLOCK(zone);
674 		bucket_drain(zone, bucket);
675 		bucket_free(bucket);
676 		ZONE_LOCK(zone);
677 	}
678 
679 	/* Now we do the free queue.. */
680 	while ((bucket = LIST_FIRST(&zone->uz_free_bucket)) != NULL) {
681 		LIST_REMOVE(bucket, ub_link);
682 		bucket_free(bucket);
683 	}
684 }
685 
686 /*
687  * Frees pages from a keg back to the system.  This is done on demand from
688  * the pageout daemon.
689  *
690  * Returns nothing.
691  */
692 static void
693 keg_drain(uma_keg_t keg)
694 {
695 	struct slabhead freeslabs = { 0 };
696 	uma_slab_t slab;
697 	uma_slab_t n;
698 	uint8_t flags;
699 	uint8_t *mem;
700 	int i;
701 
702 	/*
703 	 * We don't want to take pages from statically allocated kegs at this
704 	 * time
705 	 */
706 	if (keg->uk_flags & UMA_ZONE_NOFREE || keg->uk_freef == NULL)
707 		return;
708 
709 #ifdef UMA_DEBUG
710 	printf("%s free items: %u\n", keg->uk_name, keg->uk_free);
711 #endif
712 	KEG_LOCK(keg);
713 	if (keg->uk_free == 0)
714 		goto finished;
715 
716 	slab = LIST_FIRST(&keg->uk_free_slab);
717 	while (slab) {
718 		n = LIST_NEXT(slab, us_link);
719 
720 		/* We have no where to free these to */
721 		if (slab->us_flags & UMA_SLAB_BOOT) {
722 			slab = n;
723 			continue;
724 		}
725 
726 		LIST_REMOVE(slab, us_link);
727 		keg->uk_pages -= keg->uk_ppera;
728 		keg->uk_free -= keg->uk_ipers;
729 
730 		if (keg->uk_flags & UMA_ZONE_HASH)
731 			UMA_HASH_REMOVE(&keg->uk_hash, slab, slab->us_data);
732 
733 		SLIST_INSERT_HEAD(&freeslabs, slab, us_hlink);
734 
735 		slab = n;
736 	}
737 finished:
738 	KEG_UNLOCK(keg);
739 
740 	while ((slab = SLIST_FIRST(&freeslabs)) != NULL) {
741 		SLIST_REMOVE(&freeslabs, slab, uma_slab, us_hlink);
742 		if (keg->uk_fini)
743 			for (i = 0; i < keg->uk_ipers; i++)
744 				keg->uk_fini(
745 				    slab->us_data + (keg->uk_rsize * i),
746 				    keg->uk_size);
747 		flags = slab->us_flags;
748 		mem = slab->us_data;
749 
750 		if (keg->uk_flags & UMA_ZONE_VTOSLAB) {
751 			vm_object_t obj;
752 
753 			if (flags & UMA_SLAB_KMEM)
754 				obj = kmem_object;
755 			else if (flags & UMA_SLAB_KERNEL)
756 				obj = kernel_object;
757 			else
758 				obj = NULL;
759 			for (i = 0; i < keg->uk_ppera; i++)
760 				vsetobj((vm_offset_t)mem + (i * PAGE_SIZE),
761 				    obj);
762 		}
763 		if (keg->uk_flags & UMA_ZONE_OFFPAGE)
764 			zone_free_item(keg->uk_slabzone, slab, NULL,
765 			    SKIP_NONE, ZFREE_STATFREE);
766 #ifdef UMA_DEBUG
767 		printf("%s: Returning %d bytes.\n",
768 		    keg->uk_name, PAGE_SIZE * keg->uk_ppera);
769 #endif
770 		keg->uk_freef(mem, PAGE_SIZE * keg->uk_ppera, flags);
771 	}
772 }
773 
774 static void
775 zone_drain_wait(uma_zone_t zone, int waitok)
776 {
777 
778 	/*
779 	 * Set draining to interlock with zone_dtor() so we can release our
780 	 * locks as we go.  Only dtor() should do a WAITOK call since it
781 	 * is the only call that knows the structure will still be available
782 	 * when it wakes up.
783 	 */
784 	ZONE_LOCK(zone);
785 	while (zone->uz_flags & UMA_ZFLAG_DRAINING) {
786 		if (waitok == M_NOWAIT)
787 			goto out;
788 		mtx_unlock(&uma_mtx);
789 		msleep(zone, zone->uz_lock, PVM, "zonedrain", 1);
790 		mtx_lock(&uma_mtx);
791 	}
792 	zone->uz_flags |= UMA_ZFLAG_DRAINING;
793 	bucket_cache_drain(zone);
794 	ZONE_UNLOCK(zone);
795 	/*
796 	 * The DRAINING flag protects us from being freed while
797 	 * we're running.  Normally the uma_mtx would protect us but we
798 	 * must be able to release and acquire the right lock for each keg.
799 	 */
800 	zone_foreach_keg(zone, &keg_drain);
801 	ZONE_LOCK(zone);
802 	zone->uz_flags &= ~UMA_ZFLAG_DRAINING;
803 	wakeup(zone);
804 out:
805 	ZONE_UNLOCK(zone);
806 }
807 
808 void
809 zone_drain(uma_zone_t zone)
810 {
811 
812 	zone_drain_wait(zone, M_NOWAIT);
813 }
814 
815 /*
816  * Allocate a new slab for a keg.  This does not insert the slab onto a list.
817  *
818  * Arguments:
819  *	wait  Shall we wait?
820  *
821  * Returns:
822  *	The slab that was allocated or NULL if there is no memory and the
823  *	caller specified M_NOWAIT.
824  */
825 static uma_slab_t
826 keg_alloc_slab(uma_keg_t keg, uma_zone_t zone, int wait)
827 {
828 	uma_slabrefcnt_t slabref;
829 	uma_alloc allocf;
830 	uma_slab_t slab;
831 	uint8_t *mem;
832 	uint8_t flags;
833 	int i;
834 
835 	mtx_assert(&keg->uk_lock, MA_OWNED);
836 	slab = NULL;
837 
838 #ifdef UMA_DEBUG
839 	printf("slab_zalloc:  Allocating a new slab for %s\n", keg->uk_name);
840 #endif
841 	allocf = keg->uk_allocf;
842 	KEG_UNLOCK(keg);
843 
844 	if (keg->uk_flags & UMA_ZONE_OFFPAGE) {
845 		slab = zone_alloc_item(keg->uk_slabzone, NULL, wait);
846 		if (slab == NULL) {
847 			KEG_LOCK(keg);
848 			return NULL;
849 		}
850 	}
851 
852 	/*
853 	 * This reproduces the old vm_zone behavior of zero filling pages the
854 	 * first time they are added to a zone.
855 	 *
856 	 * Malloced items are zeroed in uma_zalloc.
857 	 */
858 
859 	if ((keg->uk_flags & UMA_ZONE_MALLOC) == 0)
860 		wait |= M_ZERO;
861 	else
862 		wait &= ~M_ZERO;
863 
864 	if (keg->uk_flags & UMA_ZONE_NODUMP)
865 		wait |= M_NODUMP;
866 
867 	/* zone is passed for legacy reasons. */
868 	mem = allocf(zone, keg->uk_ppera * PAGE_SIZE, &flags, wait);
869 	if (mem == NULL) {
870 		if (keg->uk_flags & UMA_ZONE_OFFPAGE)
871 			zone_free_item(keg->uk_slabzone, slab, NULL,
872 			    SKIP_NONE, ZFREE_STATFREE);
873 		KEG_LOCK(keg);
874 		return (NULL);
875 	}
876 
877 	/* Point the slab into the allocated memory */
878 	if (!(keg->uk_flags & UMA_ZONE_OFFPAGE))
879 		slab = (uma_slab_t )(mem + keg->uk_pgoff);
880 
881 	if (keg->uk_flags & UMA_ZONE_VTOSLAB)
882 		for (i = 0; i < keg->uk_ppera; i++)
883 			vsetslab((vm_offset_t)mem + (i * PAGE_SIZE), slab);
884 
885 	slab->us_keg = keg;
886 	slab->us_data = mem;
887 	slab->us_freecount = keg->uk_ipers;
888 	slab->us_firstfree = 0;
889 	slab->us_flags = flags;
890 
891 	if (keg->uk_flags & UMA_ZONE_REFCNT) {
892 		slabref = (uma_slabrefcnt_t)slab;
893 		for (i = 0; i < keg->uk_ipers; i++) {
894 			slabref->us_freelist[i].us_refcnt = 0;
895 			slabref->us_freelist[i].us_item = i+1;
896 		}
897 	} else {
898 		for (i = 0; i < keg->uk_ipers; i++)
899 			slab->us_freelist[i].us_item = i+1;
900 	}
901 
902 	if (keg->uk_init != NULL) {
903 		for (i = 0; i < keg->uk_ipers; i++)
904 			if (keg->uk_init(slab->us_data + (keg->uk_rsize * i),
905 			    keg->uk_size, wait) != 0)
906 				break;
907 		if (i != keg->uk_ipers) {
908 			if (keg->uk_fini != NULL) {
909 				for (i--; i > -1; i--)
910 					keg->uk_fini(slab->us_data +
911 					    (keg->uk_rsize * i),
912 					    keg->uk_size);
913 			}
914 			if (keg->uk_flags & UMA_ZONE_VTOSLAB) {
915 				vm_object_t obj;
916 
917 				if (flags & UMA_SLAB_KMEM)
918 					obj = kmem_object;
919 				else if (flags & UMA_SLAB_KERNEL)
920 					obj = kernel_object;
921 				else
922 					obj = NULL;
923 				for (i = 0; i < keg->uk_ppera; i++)
924 					vsetobj((vm_offset_t)mem +
925 					    (i * PAGE_SIZE), obj);
926 			}
927 			if (keg->uk_flags & UMA_ZONE_OFFPAGE)
928 				zone_free_item(keg->uk_slabzone, slab,
929 				    NULL, SKIP_NONE, ZFREE_STATFREE);
930 			keg->uk_freef(mem, PAGE_SIZE * keg->uk_ppera,
931 			    flags);
932 			KEG_LOCK(keg);
933 			return (NULL);
934 		}
935 	}
936 	KEG_LOCK(keg);
937 
938 	if (keg->uk_flags & UMA_ZONE_HASH)
939 		UMA_HASH_INSERT(&keg->uk_hash, slab, mem);
940 
941 	keg->uk_pages += keg->uk_ppera;
942 	keg->uk_free += keg->uk_ipers;
943 
944 	return (slab);
945 }
946 
947 /*
948  * This function is intended to be used early on in place of page_alloc() so
949  * that we may use the boot time page cache to satisfy allocations before
950  * the VM is ready.
951  */
952 static void *
953 startup_alloc(uma_zone_t zone, int bytes, uint8_t *pflag, int wait)
954 {
955 	uma_keg_t keg;
956 	uma_slab_t tmps;
957 	int pages, check_pages;
958 
959 	keg = zone_first_keg(zone);
960 	pages = howmany(bytes, PAGE_SIZE);
961 	check_pages = pages - 1;
962 	KASSERT(pages > 0, ("startup_alloc can't reserve 0 pages\n"));
963 
964 	/*
965 	 * Check our small startup cache to see if it has pages remaining.
966 	 */
967 	mtx_lock(&uma_boot_pages_mtx);
968 
969 	/* First check if we have enough room. */
970 	tmps = LIST_FIRST(&uma_boot_pages);
971 	while (tmps != NULL && check_pages-- > 0)
972 		tmps = LIST_NEXT(tmps, us_link);
973 	if (tmps != NULL) {
974 		/*
975 		 * It's ok to lose tmps references.  The last one will
976 		 * have tmps->us_data pointing to the start address of
977 		 * "pages" contiguous pages of memory.
978 		 */
979 		while (pages-- > 0) {
980 			tmps = LIST_FIRST(&uma_boot_pages);
981 			LIST_REMOVE(tmps, us_link);
982 		}
983 		mtx_unlock(&uma_boot_pages_mtx);
984 		*pflag = tmps->us_flags;
985 		return (tmps->us_data);
986 	}
987 	mtx_unlock(&uma_boot_pages_mtx);
988 	if (booted < UMA_STARTUP2)
989 		panic("UMA: Increase vm.boot_pages");
990 	/*
991 	 * Now that we've booted reset these users to their real allocator.
992 	 */
993 #ifdef UMA_MD_SMALL_ALLOC
994 	keg->uk_allocf = (keg->uk_ppera > 1) ? page_alloc : uma_small_alloc;
995 #else
996 	keg->uk_allocf = page_alloc;
997 #endif
998 	return keg->uk_allocf(zone, bytes, pflag, wait);
999 }
1000 
1001 /*
1002  * Allocates a number of pages from the system
1003  *
1004  * Arguments:
1005  *	bytes  The number of bytes requested
1006  *	wait  Shall we wait?
1007  *
1008  * Returns:
1009  *	A pointer to the alloced memory or possibly
1010  *	NULL if M_NOWAIT is set.
1011  */
1012 static void *
1013 page_alloc(uma_zone_t zone, int bytes, uint8_t *pflag, int wait)
1014 {
1015 	void *p;	/* Returned page */
1016 
1017 	*pflag = UMA_SLAB_KMEM;
1018 	p = (void *) kmem_malloc(kmem_map, bytes, wait);
1019 
1020 	return (p);
1021 }
1022 
1023 /*
1024  * Allocates a number of pages from within an object
1025  *
1026  * Arguments:
1027  *	bytes  The number of bytes requested
1028  *	wait   Shall we wait?
1029  *
1030  * Returns:
1031  *	A pointer to the alloced memory or possibly
1032  *	NULL if M_NOWAIT is set.
1033  */
1034 static void *
1035 noobj_alloc(uma_zone_t zone, int bytes, uint8_t *flags, int wait)
1036 {
1037 	TAILQ_HEAD(, vm_page) alloctail;
1038 	u_long npages;
1039 	vm_offset_t retkva, zkva;
1040 	vm_page_t p, p_next;
1041 	uma_keg_t keg;
1042 
1043 	TAILQ_INIT(&alloctail);
1044 	keg = zone_first_keg(zone);
1045 
1046 	npages = howmany(bytes, PAGE_SIZE);
1047 	while (npages > 0) {
1048 		p = vm_page_alloc(NULL, 0, VM_ALLOC_INTERRUPT |
1049 		    VM_ALLOC_WIRED | VM_ALLOC_NOOBJ);
1050 		if (p != NULL) {
1051 			/*
1052 			 * Since the page does not belong to an object, its
1053 			 * listq is unused.
1054 			 */
1055 			TAILQ_INSERT_TAIL(&alloctail, p, listq);
1056 			npages--;
1057 			continue;
1058 		}
1059 		if (wait & M_WAITOK) {
1060 			VM_WAIT;
1061 			continue;
1062 		}
1063 
1064 		/*
1065 		 * Page allocation failed, free intermediate pages and
1066 		 * exit.
1067 		 */
1068 		TAILQ_FOREACH_SAFE(p, &alloctail, listq, p_next) {
1069 			vm_page_unwire(p, 0);
1070 			vm_page_free(p);
1071 		}
1072 		return (NULL);
1073 	}
1074 	*flags = UMA_SLAB_PRIV;
1075 	zkva = keg->uk_kva +
1076 	    atomic_fetchadd_long(&keg->uk_offset, round_page(bytes));
1077 	retkva = zkva;
1078 	TAILQ_FOREACH(p, &alloctail, listq) {
1079 		pmap_qenter(zkva, &p, 1);
1080 		zkva += PAGE_SIZE;
1081 	}
1082 
1083 	return ((void *)retkva);
1084 }
1085 
1086 /*
1087  * Frees a number of pages to the system
1088  *
1089  * Arguments:
1090  *	mem   A pointer to the memory to be freed
1091  *	size  The size of the memory being freed
1092  *	flags The original p->us_flags field
1093  *
1094  * Returns:
1095  *	Nothing
1096  */
1097 static void
1098 page_free(void *mem, int size, uint8_t flags)
1099 {
1100 	vm_map_t map;
1101 
1102 	if (flags & UMA_SLAB_KMEM)
1103 		map = kmem_map;
1104 	else if (flags & UMA_SLAB_KERNEL)
1105 		map = kernel_map;
1106 	else
1107 		panic("UMA: page_free used with invalid flags %d", flags);
1108 
1109 	kmem_free(map, (vm_offset_t)mem, size);
1110 }
1111 
1112 /*
1113  * Zero fill initializer
1114  *
1115  * Arguments/Returns follow uma_init specifications
1116  */
1117 static int
1118 zero_init(void *mem, int size, int flags)
1119 {
1120 	bzero(mem, size);
1121 	return (0);
1122 }
1123 
1124 /*
1125  * Finish creating a small uma keg.  This calculates ipers, and the keg size.
1126  *
1127  * Arguments
1128  *	keg  The zone we should initialize
1129  *
1130  * Returns
1131  *	Nothing
1132  */
1133 static void
1134 keg_small_init(uma_keg_t keg)
1135 {
1136 	u_int rsize;
1137 	u_int memused;
1138 	u_int wastedspace;
1139 	u_int shsize;
1140 
1141 	if (keg->uk_flags & UMA_ZONE_PCPU) {
1142 		KASSERT(mp_ncpus > 0, ("%s: ncpus %d\n", __func__, mp_ncpus));
1143 		keg->uk_slabsize = sizeof(struct pcpu);
1144 		keg->uk_ppera = howmany(mp_ncpus * sizeof(struct pcpu),
1145 		    PAGE_SIZE);
1146 	} else {
1147 		keg->uk_slabsize = UMA_SLAB_SIZE;
1148 		keg->uk_ppera = 1;
1149 	}
1150 
1151 	rsize = keg->uk_size;
1152 
1153 	if (rsize & keg->uk_align)
1154 		rsize = (rsize & ~keg->uk_align) + (keg->uk_align + 1);
1155 	if (rsize < keg->uk_slabsize / 256)
1156 		rsize = keg->uk_slabsize / 256;
1157 
1158 	keg->uk_rsize = rsize;
1159 
1160 	KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0 ||
1161 	    keg->uk_rsize < sizeof(struct pcpu),
1162 	    ("%s: size %u too large", __func__, keg->uk_rsize));
1163 
1164 	if (keg->uk_flags & UMA_ZONE_OFFPAGE) {
1165 		shsize = 0;
1166 	} else if (keg->uk_flags & UMA_ZONE_REFCNT) {
1167 		rsize += UMA_FRITMREF_SZ;	/* linkage & refcnt */
1168 		shsize = sizeof(struct uma_slab_refcnt);
1169 	} else {
1170 		rsize += UMA_FRITM_SZ;	/* Account for linkage */
1171 		shsize = sizeof(struct uma_slab);
1172 	}
1173 
1174 	keg->uk_ipers = (keg->uk_slabsize - shsize) / rsize;
1175 	KASSERT(keg->uk_ipers > 0 && keg->uk_ipers <= 256,
1176 	    ("%s: keg->uk_ipers %u", __func__, keg->uk_ipers));
1177 
1178 	memused = keg->uk_ipers * rsize + shsize;
1179 	wastedspace = keg->uk_slabsize - memused;
1180 
1181 	/*
1182 	 * We can't do OFFPAGE if we're internal or if we've been
1183 	 * asked to not go to the VM for buckets.  If we do this we
1184 	 * may end up going to the VM (kmem_map) for slabs which we
1185 	 * do not want to do if we're UMA_ZFLAG_CACHEONLY as a
1186 	 * result of UMA_ZONE_VM, which clearly forbids it.
1187 	 */
1188 	if ((keg->uk_flags & UMA_ZFLAG_INTERNAL) ||
1189 	    (keg->uk_flags & UMA_ZFLAG_CACHEONLY))
1190 		return;
1191 
1192 	if ((wastedspace >= keg->uk_slabsize / UMA_MAX_WASTE) &&
1193 	    (keg->uk_ipers < (keg->uk_slabsize / keg->uk_rsize))) {
1194 		keg->uk_ipers = keg->uk_slabsize / keg->uk_rsize;
1195 		KASSERT(keg->uk_ipers > 0 && keg->uk_ipers <= 256,
1196 		    ("%s: keg->uk_ipers %u", __func__, keg->uk_ipers));
1197 #ifdef UMA_DEBUG
1198 		printf("UMA decided we need offpage slab headers for "
1199 		    "keg: %s, calculated wastedspace = %d, "
1200 		    "maximum wasted space allowed = %d, "
1201 		    "calculated ipers = %d, "
1202 		    "new wasted space = %d\n", keg->uk_name, wastedspace,
1203 		    keg->uk_slabsize / UMA_MAX_WASTE, keg->uk_ipers,
1204 		    keg->uk_slabsize - keg->uk_ipers * keg->uk_rsize);
1205 #endif
1206 		keg->uk_flags |= UMA_ZONE_OFFPAGE;
1207 	}
1208 
1209 	if ((keg->uk_flags & UMA_ZONE_OFFPAGE) &&
1210 	    (keg->uk_flags & UMA_ZONE_VTOSLAB) == 0)
1211 		keg->uk_flags |= UMA_ZONE_HASH;
1212 }
1213 
1214 /*
1215  * Finish creating a large (> UMA_SLAB_SIZE) uma kegs.  Just give in and do
1216  * OFFPAGE for now.  When I can allow for more dynamic slab sizes this will be
1217  * more complicated.
1218  *
1219  * Arguments
1220  *	keg  The keg we should initialize
1221  *
1222  * Returns
1223  *	Nothing
1224  */
1225 static void
1226 keg_large_init(uma_keg_t keg)
1227 {
1228 
1229 	KASSERT(keg != NULL, ("Keg is null in keg_large_init"));
1230 	KASSERT((keg->uk_flags & UMA_ZFLAG_CACHEONLY) == 0,
1231 	    ("keg_large_init: Cannot large-init a UMA_ZFLAG_CACHEONLY keg"));
1232 	KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0,
1233 	    ("%s: Cannot large-init a UMA_ZONE_PCPU keg", __func__));
1234 
1235 	keg->uk_ppera = howmany(keg->uk_size, PAGE_SIZE);
1236 	keg->uk_slabsize = keg->uk_ppera * PAGE_SIZE;
1237 	keg->uk_ipers = 1;
1238 	keg->uk_rsize = keg->uk_size;
1239 
1240 	/* We can't do OFFPAGE if we're internal, bail out here. */
1241 	if (keg->uk_flags & UMA_ZFLAG_INTERNAL)
1242 		return;
1243 
1244 	keg->uk_flags |= UMA_ZONE_OFFPAGE;
1245 	if ((keg->uk_flags & UMA_ZONE_VTOSLAB) == 0)
1246 		keg->uk_flags |= UMA_ZONE_HASH;
1247 }
1248 
1249 static void
1250 keg_cachespread_init(uma_keg_t keg)
1251 {
1252 	int alignsize;
1253 	int trailer;
1254 	int pages;
1255 	int rsize;
1256 
1257 	KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0,
1258 	    ("%s: Cannot cachespread-init a UMA_ZONE_PCPU keg", __func__));
1259 
1260 	alignsize = keg->uk_align + 1;
1261 	rsize = keg->uk_size;
1262 	/*
1263 	 * We want one item to start on every align boundary in a page.  To
1264 	 * do this we will span pages.  We will also extend the item by the
1265 	 * size of align if it is an even multiple of align.  Otherwise, it
1266 	 * would fall on the same boundary every time.
1267 	 */
1268 	if (rsize & keg->uk_align)
1269 		rsize = (rsize & ~keg->uk_align) + alignsize;
1270 	if ((rsize & alignsize) == 0)
1271 		rsize += alignsize;
1272 	trailer = rsize - keg->uk_size;
1273 	pages = (rsize * (PAGE_SIZE / alignsize)) / PAGE_SIZE;
1274 	pages = MIN(pages, (128 * 1024) / PAGE_SIZE);
1275 	keg->uk_rsize = rsize;
1276 	keg->uk_ppera = pages;
1277 	keg->uk_slabsize = UMA_SLAB_SIZE;
1278 	keg->uk_ipers = ((pages * PAGE_SIZE) + trailer) / rsize;
1279 	keg->uk_flags |= UMA_ZONE_OFFPAGE | UMA_ZONE_VTOSLAB;
1280 	KASSERT(keg->uk_ipers <= uma_max_ipers,
1281 	    ("%s: keg->uk_ipers too high(%d) increase max_ipers", __func__,
1282 	    keg->uk_ipers));
1283 }
1284 
1285 /*
1286  * Keg header ctor.  This initializes all fields, locks, etc.  And inserts
1287  * the keg onto the global keg list.
1288  *
1289  * Arguments/Returns follow uma_ctor specifications
1290  *	udata  Actually uma_kctor_args
1291  */
1292 static int
1293 keg_ctor(void *mem, int size, void *udata, int flags)
1294 {
1295 	struct uma_kctor_args *arg = udata;
1296 	uma_keg_t keg = mem;
1297 	uma_zone_t zone;
1298 
1299 	bzero(keg, size);
1300 	keg->uk_size = arg->size;
1301 	keg->uk_init = arg->uminit;
1302 	keg->uk_fini = arg->fini;
1303 	keg->uk_align = arg->align;
1304 	keg->uk_free = 0;
1305 	keg->uk_pages = 0;
1306 	keg->uk_flags = arg->flags;
1307 	keg->uk_allocf = page_alloc;
1308 	keg->uk_freef = page_free;
1309 	keg->uk_recurse = 0;
1310 	keg->uk_slabzone = NULL;
1311 
1312 	/*
1313 	 * The master zone is passed to us at keg-creation time.
1314 	 */
1315 	zone = arg->zone;
1316 	keg->uk_name = zone->uz_name;
1317 
1318 	if (arg->flags & UMA_ZONE_VM)
1319 		keg->uk_flags |= UMA_ZFLAG_CACHEONLY;
1320 
1321 	if (arg->flags & UMA_ZONE_ZINIT)
1322 		keg->uk_init = zero_init;
1323 
1324 	if (arg->flags & UMA_ZONE_REFCNT || arg->flags & UMA_ZONE_MALLOC)
1325 		keg->uk_flags |= UMA_ZONE_VTOSLAB;
1326 
1327 	if (arg->flags & UMA_ZONE_PCPU)
1328 #ifdef SMP
1329 		keg->uk_flags |= UMA_ZONE_OFFPAGE;
1330 #else
1331 		keg->uk_flags &= ~UMA_ZONE_PCPU;
1332 #endif
1333 
1334 	/*
1335 	 * The +UMA_FRITM_SZ added to uk_size is to account for the
1336 	 * linkage that is added to the size in keg_small_init().  If
1337 	 * we don't account for this here then we may end up in
1338 	 * keg_small_init() with a calculated 'ipers' of 0.
1339 	 */
1340 	if (keg->uk_flags & UMA_ZONE_REFCNT) {
1341 		if (keg->uk_flags & UMA_ZONE_CACHESPREAD)
1342 			keg_cachespread_init(keg);
1343 		else if ((keg->uk_size+UMA_FRITMREF_SZ) >
1344 		    (UMA_SLAB_SIZE - sizeof(struct uma_slab_refcnt)))
1345 			keg_large_init(keg);
1346 		else
1347 			keg_small_init(keg);
1348 	} else {
1349 		if (keg->uk_flags & UMA_ZONE_CACHESPREAD)
1350 			keg_cachespread_init(keg);
1351 		else if ((keg->uk_size+UMA_FRITM_SZ) >
1352 		    (UMA_SLAB_SIZE - sizeof(struct uma_slab)))
1353 			keg_large_init(keg);
1354 		else
1355 			keg_small_init(keg);
1356 	}
1357 
1358 	if (keg->uk_flags & UMA_ZONE_OFFPAGE) {
1359 		if (keg->uk_flags & UMA_ZONE_REFCNT)
1360 			keg->uk_slabzone = slabrefzone;
1361 		else
1362 			keg->uk_slabzone = slabzone;
1363 	}
1364 
1365 	/*
1366 	 * If we haven't booted yet we need allocations to go through the
1367 	 * startup cache until the vm is ready.
1368 	 */
1369 	if (keg->uk_ppera == 1) {
1370 #ifdef UMA_MD_SMALL_ALLOC
1371 		keg->uk_allocf = uma_small_alloc;
1372 		keg->uk_freef = uma_small_free;
1373 
1374 		if (booted < UMA_STARTUP)
1375 			keg->uk_allocf = startup_alloc;
1376 #else
1377 		if (booted < UMA_STARTUP2)
1378 			keg->uk_allocf = startup_alloc;
1379 #endif
1380 	} else if (booted < UMA_STARTUP2 &&
1381 	    (keg->uk_flags & UMA_ZFLAG_INTERNAL))
1382 		keg->uk_allocf = startup_alloc;
1383 
1384 	/*
1385 	 * Initialize keg's lock (shared among zones).
1386 	 */
1387 	if (arg->flags & UMA_ZONE_MTXCLASS)
1388 		KEG_LOCK_INIT(keg, 1);
1389 	else
1390 		KEG_LOCK_INIT(keg, 0);
1391 
1392 	/*
1393 	 * If we're putting the slab header in the actual page we need to
1394 	 * figure out where in each page it goes.  This calculates a right
1395 	 * justified offset into the memory on an ALIGN_PTR boundary.
1396 	 */
1397 	if (!(keg->uk_flags & UMA_ZONE_OFFPAGE)) {
1398 		u_int totsize;
1399 
1400 		/* Size of the slab struct and free list */
1401 		if (keg->uk_flags & UMA_ZONE_REFCNT)
1402 			totsize = sizeof(struct uma_slab_refcnt) +
1403 			    keg->uk_ipers * UMA_FRITMREF_SZ;
1404 		else
1405 			totsize = sizeof(struct uma_slab) +
1406 			    keg->uk_ipers * UMA_FRITM_SZ;
1407 
1408 		if (totsize & UMA_ALIGN_PTR)
1409 			totsize = (totsize & ~UMA_ALIGN_PTR) +
1410 			    (UMA_ALIGN_PTR + 1);
1411 		keg->uk_pgoff = (PAGE_SIZE * keg->uk_ppera) - totsize;
1412 
1413 		if (keg->uk_flags & UMA_ZONE_REFCNT)
1414 			totsize = keg->uk_pgoff + sizeof(struct uma_slab_refcnt)
1415 			    + keg->uk_ipers * UMA_FRITMREF_SZ;
1416 		else
1417 			totsize = keg->uk_pgoff + sizeof(struct uma_slab)
1418 			    + keg->uk_ipers * UMA_FRITM_SZ;
1419 
1420 		/*
1421 		 * The only way the following is possible is if with our
1422 		 * UMA_ALIGN_PTR adjustments we are now bigger than
1423 		 * UMA_SLAB_SIZE.  I haven't checked whether this is
1424 		 * mathematically possible for all cases, so we make
1425 		 * sure here anyway.
1426 		 */
1427 		if (totsize > PAGE_SIZE * keg->uk_ppera) {
1428 			printf("zone %s ipers %d rsize %d size %d\n",
1429 			    zone->uz_name, keg->uk_ipers, keg->uk_rsize,
1430 			    keg->uk_size);
1431 			panic("UMA slab won't fit.");
1432 		}
1433 	}
1434 
1435 	if (keg->uk_flags & UMA_ZONE_HASH)
1436 		hash_alloc(&keg->uk_hash);
1437 
1438 #ifdef UMA_DEBUG
1439 	printf("UMA: %s(%p) size %d(%d) flags %#x ipers %d ppera %d out %d free %d\n",
1440 	    zone->uz_name, zone, keg->uk_size, keg->uk_rsize, keg->uk_flags,
1441 	    keg->uk_ipers, keg->uk_ppera,
1442 	    (keg->uk_ipers * keg->uk_pages) - keg->uk_free, keg->uk_free);
1443 #endif
1444 
1445 	LIST_INSERT_HEAD(&keg->uk_zones, zone, uz_link);
1446 
1447 	mtx_lock(&uma_mtx);
1448 	LIST_INSERT_HEAD(&uma_kegs, keg, uk_link);
1449 	mtx_unlock(&uma_mtx);
1450 	return (0);
1451 }
1452 
1453 /*
1454  * Zone header ctor.  This initializes all fields, locks, etc.
1455  *
1456  * Arguments/Returns follow uma_ctor specifications
1457  *	udata  Actually uma_zctor_args
1458  */
1459 static int
1460 zone_ctor(void *mem, int size, void *udata, int flags)
1461 {
1462 	struct uma_zctor_args *arg = udata;
1463 	uma_zone_t zone = mem;
1464 	uma_zone_t z;
1465 	uma_keg_t keg;
1466 
1467 	bzero(zone, size);
1468 	zone->uz_name = arg->name;
1469 	zone->uz_ctor = arg->ctor;
1470 	zone->uz_dtor = arg->dtor;
1471 	zone->uz_slab = zone_fetch_slab;
1472 	zone->uz_init = NULL;
1473 	zone->uz_fini = NULL;
1474 	zone->uz_allocs = 0;
1475 	zone->uz_frees = 0;
1476 	zone->uz_fails = 0;
1477 	zone->uz_sleeps = 0;
1478 	zone->uz_fills = zone->uz_count = 0;
1479 	zone->uz_flags = 0;
1480 	zone->uz_warning = NULL;
1481 	timevalclear(&zone->uz_ratecheck);
1482 	keg = arg->keg;
1483 
1484 	if (arg->flags & UMA_ZONE_SECONDARY) {
1485 		KASSERT(arg->keg != NULL, ("Secondary zone on zero'd keg"));
1486 		zone->uz_init = arg->uminit;
1487 		zone->uz_fini = arg->fini;
1488 		zone->uz_lock = &keg->uk_lock;
1489 		zone->uz_flags |= UMA_ZONE_SECONDARY;
1490 		mtx_lock(&uma_mtx);
1491 		ZONE_LOCK(zone);
1492 		LIST_FOREACH(z, &keg->uk_zones, uz_link) {
1493 			if (LIST_NEXT(z, uz_link) == NULL) {
1494 				LIST_INSERT_AFTER(z, zone, uz_link);
1495 				break;
1496 			}
1497 		}
1498 		ZONE_UNLOCK(zone);
1499 		mtx_unlock(&uma_mtx);
1500 	} else if (keg == NULL) {
1501 		if ((keg = uma_kcreate(zone, arg->size, arg->uminit, arg->fini,
1502 		    arg->align, arg->flags)) == NULL)
1503 			return (ENOMEM);
1504 	} else {
1505 		struct uma_kctor_args karg;
1506 		int error;
1507 
1508 		/* We should only be here from uma_startup() */
1509 		karg.size = arg->size;
1510 		karg.uminit = arg->uminit;
1511 		karg.fini = arg->fini;
1512 		karg.align = arg->align;
1513 		karg.flags = arg->flags;
1514 		karg.zone = zone;
1515 		error = keg_ctor(arg->keg, sizeof(struct uma_keg), &karg,
1516 		    flags);
1517 		if (error)
1518 			return (error);
1519 	}
1520 	/*
1521 	 * Link in the first keg.
1522 	 */
1523 	zone->uz_klink.kl_keg = keg;
1524 	LIST_INSERT_HEAD(&zone->uz_kegs, &zone->uz_klink, kl_link);
1525 	zone->uz_lock = &keg->uk_lock;
1526 	zone->uz_size = keg->uk_size;
1527 	zone->uz_flags |= (keg->uk_flags &
1528 	    (UMA_ZONE_INHERIT | UMA_ZFLAG_INHERIT));
1529 
1530 	/*
1531 	 * Some internal zones don't have room allocated for the per cpu
1532 	 * caches.  If we're internal, bail out here.
1533 	 */
1534 	if (keg->uk_flags & UMA_ZFLAG_INTERNAL) {
1535 		KASSERT((zone->uz_flags & UMA_ZONE_SECONDARY) == 0,
1536 		    ("Secondary zone requested UMA_ZFLAG_INTERNAL"));
1537 		return (0);
1538 	}
1539 
1540 	if (keg->uk_flags & UMA_ZONE_MAXBUCKET)
1541 		zone->uz_count = BUCKET_MAX;
1542 	else if (keg->uk_ipers <= BUCKET_MAX)
1543 		zone->uz_count = keg->uk_ipers;
1544 	else
1545 		zone->uz_count = BUCKET_MAX;
1546 	return (0);
1547 }
1548 
1549 /*
1550  * Keg header dtor.  This frees all data, destroys locks, frees the hash
1551  * table and removes the keg from the global list.
1552  *
1553  * Arguments/Returns follow uma_dtor specifications
1554  *	udata  unused
1555  */
1556 static void
1557 keg_dtor(void *arg, int size, void *udata)
1558 {
1559 	uma_keg_t keg;
1560 
1561 	keg = (uma_keg_t)arg;
1562 	KEG_LOCK(keg);
1563 	if (keg->uk_free != 0) {
1564 		printf("Freed UMA keg was not empty (%d items). "
1565 		    " Lost %d pages of memory.\n",
1566 		    keg->uk_free, keg->uk_pages);
1567 	}
1568 	KEG_UNLOCK(keg);
1569 
1570 	hash_free(&keg->uk_hash);
1571 
1572 	KEG_LOCK_FINI(keg);
1573 }
1574 
1575 /*
1576  * Zone header dtor.
1577  *
1578  * Arguments/Returns follow uma_dtor specifications
1579  *	udata  unused
1580  */
1581 static void
1582 zone_dtor(void *arg, int size, void *udata)
1583 {
1584 	uma_klink_t klink;
1585 	uma_zone_t zone;
1586 	uma_keg_t keg;
1587 
1588 	zone = (uma_zone_t)arg;
1589 	keg = zone_first_keg(zone);
1590 
1591 	if (!(zone->uz_flags & UMA_ZFLAG_INTERNAL))
1592 		cache_drain(zone);
1593 
1594 	mtx_lock(&uma_mtx);
1595 	LIST_REMOVE(zone, uz_link);
1596 	mtx_unlock(&uma_mtx);
1597 	/*
1598 	 * XXX there are some races here where
1599 	 * the zone can be drained but zone lock
1600 	 * released and then refilled before we
1601 	 * remove it... we dont care for now
1602 	 */
1603 	zone_drain_wait(zone, M_WAITOK);
1604 	/*
1605 	 * Unlink all of our kegs.
1606 	 */
1607 	while ((klink = LIST_FIRST(&zone->uz_kegs)) != NULL) {
1608 		klink->kl_keg = NULL;
1609 		LIST_REMOVE(klink, kl_link);
1610 		if (klink == &zone->uz_klink)
1611 			continue;
1612 		free(klink, M_TEMP);
1613 	}
1614 	/*
1615 	 * We only destroy kegs from non secondary zones.
1616 	 */
1617 	if ((zone->uz_flags & UMA_ZONE_SECONDARY) == 0)  {
1618 		mtx_lock(&uma_mtx);
1619 		LIST_REMOVE(keg, uk_link);
1620 		mtx_unlock(&uma_mtx);
1621 		zone_free_item(kegs, keg, NULL, SKIP_NONE,
1622 		    ZFREE_STATFREE);
1623 	}
1624 }
1625 
1626 /*
1627  * Traverses every zone in the system and calls a callback
1628  *
1629  * Arguments:
1630  *	zfunc  A pointer to a function which accepts a zone
1631  *		as an argument.
1632  *
1633  * Returns:
1634  *	Nothing
1635  */
1636 static void
1637 zone_foreach(void (*zfunc)(uma_zone_t))
1638 {
1639 	uma_keg_t keg;
1640 	uma_zone_t zone;
1641 
1642 	mtx_lock(&uma_mtx);
1643 	LIST_FOREACH(keg, &uma_kegs, uk_link) {
1644 		LIST_FOREACH(zone, &keg->uk_zones, uz_link)
1645 			zfunc(zone);
1646 	}
1647 	mtx_unlock(&uma_mtx);
1648 }
1649 
1650 /* Public functions */
1651 /* See uma.h */
1652 void
1653 uma_startup(void *bootmem, int boot_pages)
1654 {
1655 	struct uma_zctor_args args;
1656 	uma_slab_t slab;
1657 	u_int slabsize;
1658 	u_int objsize, totsize, wsize;
1659 	int i;
1660 
1661 #ifdef UMA_DEBUG
1662 	printf("Creating uma keg headers zone and keg.\n");
1663 #endif
1664 	mtx_init(&uma_mtx, "UMA lock", NULL, MTX_DEF);
1665 
1666 	/*
1667 	 * Figure out the maximum number of items-per-slab we'll have if
1668 	 * we're using the OFFPAGE slab header to track free items, given
1669 	 * all possible object sizes and the maximum desired wastage
1670 	 * (UMA_MAX_WASTE).
1671 	 *
1672 	 * We iterate until we find an object size for
1673 	 * which the calculated wastage in keg_small_init() will be
1674 	 * enough to warrant OFFPAGE.  Since wastedspace versus objsize
1675 	 * is an overall increasing see-saw function, we find the smallest
1676 	 * objsize such that the wastage is always acceptable for objects
1677 	 * with that objsize or smaller.  Since a smaller objsize always
1678 	 * generates a larger possible uma_max_ipers, we use this computed
1679 	 * objsize to calculate the largest ipers possible.  Since the
1680 	 * ipers calculated for OFFPAGE slab headers is always larger than
1681 	 * the ipers initially calculated in keg_small_init(), we use
1682 	 * the former's equation (UMA_SLAB_SIZE / keg->uk_rsize) to
1683 	 * obtain the maximum ipers possible for offpage slab headers.
1684 	 *
1685 	 * It should be noted that ipers versus objsize is an inversly
1686 	 * proportional function which drops off rather quickly so as
1687 	 * long as our UMA_MAX_WASTE is such that the objsize we calculate
1688 	 * falls into the portion of the inverse relation AFTER the steep
1689 	 * falloff, then uma_max_ipers shouldn't be too high (~10 on i386).
1690 	 *
1691 	 * Note that we have 8-bits (1 byte) to use as a freelist index
1692 	 * inside the actual slab header itself and this is enough to
1693 	 * accomodate us.  In the worst case, a UMA_SMALLEST_UNIT sized
1694 	 * object with offpage slab header would have ipers =
1695 	 * UMA_SLAB_SIZE / UMA_SMALLEST_UNIT (currently = 256), which is
1696 	 * 1 greater than what our byte-integer freelist index can
1697 	 * accomodate, but we know that this situation never occurs as
1698 	 * for UMA_SMALLEST_UNIT-sized objects, we will never calculate
1699 	 * that we need to go to offpage slab headers.  Or, if we do,
1700 	 * then we trap that condition below and panic in the INVARIANTS case.
1701 	 */
1702 	wsize = UMA_SLAB_SIZE - sizeof(struct uma_slab) -
1703 	    (UMA_SLAB_SIZE / UMA_MAX_WASTE);
1704 	totsize = wsize;
1705 	objsize = UMA_SMALLEST_UNIT;
1706 	while (totsize >= wsize) {
1707 		totsize = (UMA_SLAB_SIZE - sizeof(struct uma_slab)) /
1708 		    (objsize + UMA_FRITM_SZ);
1709 		totsize *= (UMA_FRITM_SZ + objsize);
1710 		objsize++;
1711 	}
1712 	if (objsize > UMA_SMALLEST_UNIT)
1713 		objsize--;
1714 	uma_max_ipers = MAX(UMA_SLAB_SIZE / objsize, 64);
1715 
1716 	wsize = UMA_SLAB_SIZE - sizeof(struct uma_slab_refcnt) -
1717 	    (UMA_SLAB_SIZE / UMA_MAX_WASTE);
1718 	totsize = wsize;
1719 	objsize = UMA_SMALLEST_UNIT;
1720 	while (totsize >= wsize) {
1721 		totsize = (UMA_SLAB_SIZE - sizeof(struct uma_slab_refcnt)) /
1722 		    (objsize + UMA_FRITMREF_SZ);
1723 		totsize *= (UMA_FRITMREF_SZ + objsize);
1724 		objsize++;
1725 	}
1726 	if (objsize > UMA_SMALLEST_UNIT)
1727 		objsize--;
1728 	uma_max_ipers_ref = MAX(UMA_SLAB_SIZE / objsize, 64);
1729 
1730 	KASSERT((uma_max_ipers_ref <= 256) && (uma_max_ipers <= 256),
1731 	    ("uma_startup: calculated uma_max_ipers values too large!"));
1732 
1733 #ifdef UMA_DEBUG
1734 	printf("Calculated uma_max_ipers (for OFFPAGE) is %d\n", uma_max_ipers);
1735 	printf("Calculated uma_max_ipers_ref (for OFFPAGE) is %d\n",
1736 	    uma_max_ipers_ref);
1737 #endif
1738 
1739 	/* "manually" create the initial zone */
1740 	args.name = "UMA Kegs";
1741 	args.size = sizeof(struct uma_keg);
1742 	args.ctor = keg_ctor;
1743 	args.dtor = keg_dtor;
1744 	args.uminit = zero_init;
1745 	args.fini = NULL;
1746 	args.keg = &masterkeg;
1747 	args.align = 32 - 1;
1748 	args.flags = UMA_ZFLAG_INTERNAL;
1749 	/* The initial zone has no Per cpu queues so it's smaller */
1750 	zone_ctor(kegs, sizeof(struct uma_zone), &args, M_WAITOK);
1751 
1752 #ifdef UMA_DEBUG
1753 	printf("Filling boot free list.\n");
1754 #endif
1755 	for (i = 0; i < boot_pages; i++) {
1756 		slab = (uma_slab_t)((uint8_t *)bootmem + (i * UMA_SLAB_SIZE));
1757 		slab->us_data = (uint8_t *)slab;
1758 		slab->us_flags = UMA_SLAB_BOOT;
1759 		LIST_INSERT_HEAD(&uma_boot_pages, slab, us_link);
1760 	}
1761 	mtx_init(&uma_boot_pages_mtx, "UMA boot pages", NULL, MTX_DEF);
1762 
1763 #ifdef UMA_DEBUG
1764 	printf("Creating uma zone headers zone and keg.\n");
1765 #endif
1766 	args.name = "UMA Zones";
1767 	args.size = sizeof(struct uma_zone) +
1768 	    (sizeof(struct uma_cache) * (mp_maxid + 1));
1769 	args.ctor = zone_ctor;
1770 	args.dtor = zone_dtor;
1771 	args.uminit = zero_init;
1772 	args.fini = NULL;
1773 	args.keg = NULL;
1774 	args.align = 32 - 1;
1775 	args.flags = UMA_ZFLAG_INTERNAL;
1776 	/* The initial zone has no Per cpu queues so it's smaller */
1777 	zone_ctor(zones, sizeof(struct uma_zone), &args, M_WAITOK);
1778 
1779 #ifdef UMA_DEBUG
1780 	printf("Initializing pcpu cache locks.\n");
1781 #endif
1782 #ifdef UMA_DEBUG
1783 	printf("Creating slab and hash zones.\n");
1784 #endif
1785 
1786 	/*
1787 	 * This is the max number of free list items we'll have with
1788 	 * offpage slabs.
1789 	 */
1790 	slabsize = uma_max_ipers * UMA_FRITM_SZ;
1791 	slabsize += sizeof(struct uma_slab);
1792 
1793 	/* Now make a zone for slab headers */
1794 	slabzone = uma_zcreate("UMA Slabs",
1795 				slabsize,
1796 				NULL, NULL, NULL, NULL,
1797 				UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
1798 
1799 	/*
1800 	 * We also create a zone for the bigger slabs with reference
1801 	 * counts in them, to accomodate UMA_ZONE_REFCNT zones.
1802 	 */
1803 	slabsize = uma_max_ipers_ref * UMA_FRITMREF_SZ;
1804 	slabsize += sizeof(struct uma_slab_refcnt);
1805 	slabrefzone = uma_zcreate("UMA RCntSlabs",
1806 				  slabsize,
1807 				  NULL, NULL, NULL, NULL,
1808 				  UMA_ALIGN_PTR,
1809 				  UMA_ZFLAG_INTERNAL);
1810 
1811 	hashzone = uma_zcreate("UMA Hash",
1812 	    sizeof(struct slabhead *) * UMA_HASH_SIZE_INIT,
1813 	    NULL, NULL, NULL, NULL,
1814 	    UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
1815 
1816 	bucket_init();
1817 
1818 	booted = UMA_STARTUP;
1819 
1820 #ifdef UMA_DEBUG
1821 	printf("UMA startup complete.\n");
1822 #endif
1823 }
1824 
1825 /* see uma.h */
1826 void
1827 uma_startup2(void)
1828 {
1829 	booted = UMA_STARTUP2;
1830 	bucket_enable();
1831 #ifdef UMA_DEBUG
1832 	printf("UMA startup2 complete.\n");
1833 #endif
1834 }
1835 
1836 /*
1837  * Initialize our callout handle
1838  *
1839  */
1840 
1841 static void
1842 uma_startup3(void)
1843 {
1844 #ifdef UMA_DEBUG
1845 	printf("Starting callout.\n");
1846 #endif
1847 	callout_init(&uma_callout, CALLOUT_MPSAFE);
1848 	callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL);
1849 #ifdef UMA_DEBUG
1850 	printf("UMA startup3 complete.\n");
1851 #endif
1852 }
1853 
1854 static uma_keg_t
1855 uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit, uma_fini fini,
1856 		int align, uint32_t flags)
1857 {
1858 	struct uma_kctor_args args;
1859 
1860 	args.size = size;
1861 	args.uminit = uminit;
1862 	args.fini = fini;
1863 	args.align = (align == UMA_ALIGN_CACHE) ? uma_align_cache : align;
1864 	args.flags = flags;
1865 	args.zone = zone;
1866 	return (zone_alloc_item(kegs, &args, M_WAITOK));
1867 }
1868 
1869 /* See uma.h */
1870 void
1871 uma_set_align(int align)
1872 {
1873 
1874 	if (align != UMA_ALIGN_CACHE)
1875 		uma_align_cache = align;
1876 }
1877 
1878 /* See uma.h */
1879 uma_zone_t
1880 uma_zcreate(const char *name, size_t size, uma_ctor ctor, uma_dtor dtor,
1881 		uma_init uminit, uma_fini fini, int align, uint32_t flags)
1882 
1883 {
1884 	struct uma_zctor_args args;
1885 
1886 	/* This stuff is essential for the zone ctor */
1887 	args.name = name;
1888 	args.size = size;
1889 	args.ctor = ctor;
1890 	args.dtor = dtor;
1891 	args.uminit = uminit;
1892 	args.fini = fini;
1893 	args.align = align;
1894 	args.flags = flags;
1895 	args.keg = NULL;
1896 
1897 	return (zone_alloc_item(zones, &args, M_WAITOK));
1898 }
1899 
1900 /* See uma.h */
1901 uma_zone_t
1902 uma_zsecond_create(char *name, uma_ctor ctor, uma_dtor dtor,
1903 		    uma_init zinit, uma_fini zfini, uma_zone_t master)
1904 {
1905 	struct uma_zctor_args args;
1906 	uma_keg_t keg;
1907 
1908 	keg = zone_first_keg(master);
1909 	args.name = name;
1910 	args.size = keg->uk_size;
1911 	args.ctor = ctor;
1912 	args.dtor = dtor;
1913 	args.uminit = zinit;
1914 	args.fini = zfini;
1915 	args.align = keg->uk_align;
1916 	args.flags = keg->uk_flags | UMA_ZONE_SECONDARY;
1917 	args.keg = keg;
1918 
1919 	/* XXX Attaches only one keg of potentially many. */
1920 	return (zone_alloc_item(zones, &args, M_WAITOK));
1921 }
1922 
1923 static void
1924 zone_lock_pair(uma_zone_t a, uma_zone_t b)
1925 {
1926 	if (a < b) {
1927 		ZONE_LOCK(a);
1928 		mtx_lock_flags(b->uz_lock, MTX_DUPOK);
1929 	} else {
1930 		ZONE_LOCK(b);
1931 		mtx_lock_flags(a->uz_lock, MTX_DUPOK);
1932 	}
1933 }
1934 
1935 static void
1936 zone_unlock_pair(uma_zone_t a, uma_zone_t b)
1937 {
1938 
1939 	ZONE_UNLOCK(a);
1940 	ZONE_UNLOCK(b);
1941 }
1942 
1943 int
1944 uma_zsecond_add(uma_zone_t zone, uma_zone_t master)
1945 {
1946 	uma_klink_t klink;
1947 	uma_klink_t kl;
1948 	int error;
1949 
1950 	error = 0;
1951 	klink = malloc(sizeof(*klink), M_TEMP, M_WAITOK | M_ZERO);
1952 
1953 	zone_lock_pair(zone, master);
1954 	/*
1955 	 * zone must use vtoslab() to resolve objects and must already be
1956 	 * a secondary.
1957 	 */
1958 	if ((zone->uz_flags & (UMA_ZONE_VTOSLAB | UMA_ZONE_SECONDARY))
1959 	    != (UMA_ZONE_VTOSLAB | UMA_ZONE_SECONDARY)) {
1960 		error = EINVAL;
1961 		goto out;
1962 	}
1963 	/*
1964 	 * The new master must also use vtoslab().
1965 	 */
1966 	if ((zone->uz_flags & UMA_ZONE_VTOSLAB) != UMA_ZONE_VTOSLAB) {
1967 		error = EINVAL;
1968 		goto out;
1969 	}
1970 	/*
1971 	 * Both must either be refcnt, or not be refcnt.
1972 	 */
1973 	if ((zone->uz_flags & UMA_ZONE_REFCNT) !=
1974 	    (master->uz_flags & UMA_ZONE_REFCNT)) {
1975 		error = EINVAL;
1976 		goto out;
1977 	}
1978 	/*
1979 	 * The underlying object must be the same size.  rsize
1980 	 * may be different.
1981 	 */
1982 	if (master->uz_size != zone->uz_size) {
1983 		error = E2BIG;
1984 		goto out;
1985 	}
1986 	/*
1987 	 * Put it at the end of the list.
1988 	 */
1989 	klink->kl_keg = zone_first_keg(master);
1990 	LIST_FOREACH(kl, &zone->uz_kegs, kl_link) {
1991 		if (LIST_NEXT(kl, kl_link) == NULL) {
1992 			LIST_INSERT_AFTER(kl, klink, kl_link);
1993 			break;
1994 		}
1995 	}
1996 	klink = NULL;
1997 	zone->uz_flags |= UMA_ZFLAG_MULTI;
1998 	zone->uz_slab = zone_fetch_slab_multi;
1999 
2000 out:
2001 	zone_unlock_pair(zone, master);
2002 	if (klink != NULL)
2003 		free(klink, M_TEMP);
2004 
2005 	return (error);
2006 }
2007 
2008 
2009 /* See uma.h */
2010 void
2011 uma_zdestroy(uma_zone_t zone)
2012 {
2013 
2014 	zone_free_item(zones, zone, NULL, SKIP_NONE, ZFREE_STATFREE);
2015 }
2016 
2017 /* See uma.h */
2018 void *
2019 uma_zalloc_arg(uma_zone_t zone, void *udata, int flags)
2020 {
2021 	void *item;
2022 	uma_cache_t cache;
2023 	uma_bucket_t bucket;
2024 	int cpu;
2025 
2026 	/* This is the fast path allocation */
2027 #ifdef UMA_DEBUG_ALLOC_1
2028 	printf("Allocating one item from %s(%p)\n", zone->uz_name, zone);
2029 #endif
2030 	CTR3(KTR_UMA, "uma_zalloc_arg thread %x zone %s flags %d", curthread,
2031 	    zone->uz_name, flags);
2032 
2033 	if (flags & M_WAITOK) {
2034 		WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
2035 		    "uma_zalloc_arg: zone \"%s\"", zone->uz_name);
2036 	}
2037 #ifdef DEBUG_MEMGUARD
2038 	if (memguard_cmp_zone(zone)) {
2039 		item = memguard_alloc(zone->uz_size, flags);
2040 		if (item != NULL) {
2041 			/*
2042 			 * Avoid conflict with the use-after-free
2043 			 * protecting infrastructure from INVARIANTS.
2044 			 */
2045 			if (zone->uz_init != NULL &&
2046 			    zone->uz_init != mtrash_init &&
2047 			    zone->uz_init(item, zone->uz_size, flags) != 0)
2048 				return (NULL);
2049 			if (zone->uz_ctor != NULL &&
2050 			    zone->uz_ctor != mtrash_ctor &&
2051 			    zone->uz_ctor(item, zone->uz_size, udata, flags) != 0) {
2052 			    	zone->uz_fini(item, zone->uz_size);
2053 				return (NULL);
2054 			}
2055 			return (item);
2056 		}
2057 		/* This is unfortunate but should not be fatal. */
2058 	}
2059 #endif
2060 	/*
2061 	 * If possible, allocate from the per-CPU cache.  There are two
2062 	 * requirements for safe access to the per-CPU cache: (1) the thread
2063 	 * accessing the cache must not be preempted or yield during access,
2064 	 * and (2) the thread must not migrate CPUs without switching which
2065 	 * cache it accesses.  We rely on a critical section to prevent
2066 	 * preemption and migration.  We release the critical section in
2067 	 * order to acquire the zone mutex if we are unable to allocate from
2068 	 * the current cache; when we re-acquire the critical section, we
2069 	 * must detect and handle migration if it has occurred.
2070 	 */
2071 zalloc_restart:
2072 	critical_enter();
2073 	cpu = curcpu;
2074 	cache = &zone->uz_cpu[cpu];
2075 
2076 zalloc_start:
2077 	bucket = cache->uc_allocbucket;
2078 
2079 	if (bucket) {
2080 		if (bucket->ub_cnt > 0) {
2081 			bucket->ub_cnt--;
2082 			item = bucket->ub_bucket[bucket->ub_cnt];
2083 #ifdef INVARIANTS
2084 			bucket->ub_bucket[bucket->ub_cnt] = NULL;
2085 #endif
2086 			KASSERT(item != NULL,
2087 			    ("uma_zalloc: Bucket pointer mangled."));
2088 			cache->uc_allocs++;
2089 			critical_exit();
2090 #ifdef INVARIANTS
2091 			ZONE_LOCK(zone);
2092 			uma_dbg_alloc(zone, NULL, item);
2093 			ZONE_UNLOCK(zone);
2094 #endif
2095 			if (zone->uz_ctor != NULL) {
2096 				if (zone->uz_ctor(item, zone->uz_size,
2097 				    udata, flags) != 0) {
2098 					zone_free_item(zone, item, udata,
2099 					    SKIP_DTOR, ZFREE_STATFAIL |
2100 					    ZFREE_STATFREE);
2101 					return (NULL);
2102 				}
2103 			}
2104 			if (flags & M_ZERO)
2105 				bzero(item, zone->uz_size);
2106 			return (item);
2107 		} else if (cache->uc_freebucket) {
2108 			/*
2109 			 * We have run out of items in our allocbucket.
2110 			 * See if we can switch with our free bucket.
2111 			 */
2112 			if (cache->uc_freebucket->ub_cnt > 0) {
2113 #ifdef UMA_DEBUG_ALLOC
2114 				printf("uma_zalloc: Swapping empty with"
2115 				    " alloc.\n");
2116 #endif
2117 				bucket = cache->uc_freebucket;
2118 				cache->uc_freebucket = cache->uc_allocbucket;
2119 				cache->uc_allocbucket = bucket;
2120 
2121 				goto zalloc_start;
2122 			}
2123 		}
2124 	}
2125 	/*
2126 	 * Attempt to retrieve the item from the per-CPU cache has failed, so
2127 	 * we must go back to the zone.  This requires the zone lock, so we
2128 	 * must drop the critical section, then re-acquire it when we go back
2129 	 * to the cache.  Since the critical section is released, we may be
2130 	 * preempted or migrate.  As such, make sure not to maintain any
2131 	 * thread-local state specific to the cache from prior to releasing
2132 	 * the critical section.
2133 	 */
2134 	critical_exit();
2135 	ZONE_LOCK(zone);
2136 	critical_enter();
2137 	cpu = curcpu;
2138 	cache = &zone->uz_cpu[cpu];
2139 	bucket = cache->uc_allocbucket;
2140 	if (bucket != NULL) {
2141 		if (bucket->ub_cnt > 0) {
2142 			ZONE_UNLOCK(zone);
2143 			goto zalloc_start;
2144 		}
2145 		bucket = cache->uc_freebucket;
2146 		if (bucket != NULL && bucket->ub_cnt > 0) {
2147 			ZONE_UNLOCK(zone);
2148 			goto zalloc_start;
2149 		}
2150 	}
2151 
2152 	/* Since we have locked the zone we may as well send back our stats */
2153 	zone->uz_allocs += cache->uc_allocs;
2154 	cache->uc_allocs = 0;
2155 	zone->uz_frees += cache->uc_frees;
2156 	cache->uc_frees = 0;
2157 
2158 	/* Our old one is now a free bucket */
2159 	if (cache->uc_allocbucket) {
2160 		KASSERT(cache->uc_allocbucket->ub_cnt == 0,
2161 		    ("uma_zalloc_arg: Freeing a non free bucket."));
2162 		LIST_INSERT_HEAD(&zone->uz_free_bucket,
2163 		    cache->uc_allocbucket, ub_link);
2164 		cache->uc_allocbucket = NULL;
2165 	}
2166 
2167 	/* Check the free list for a new alloc bucket */
2168 	if ((bucket = LIST_FIRST(&zone->uz_full_bucket)) != NULL) {
2169 		KASSERT(bucket->ub_cnt != 0,
2170 		    ("uma_zalloc_arg: Returning an empty bucket."));
2171 
2172 		LIST_REMOVE(bucket, ub_link);
2173 		cache->uc_allocbucket = bucket;
2174 		ZONE_UNLOCK(zone);
2175 		goto zalloc_start;
2176 	}
2177 	/* We are no longer associated with this CPU. */
2178 	critical_exit();
2179 
2180 	/* Bump up our uz_count so we get here less */
2181 	if (zone->uz_count < BUCKET_MAX)
2182 		zone->uz_count++;
2183 
2184 	/*
2185 	 * Now lets just fill a bucket and put it on the free list.  If that
2186 	 * works we'll restart the allocation from the begining.
2187 	 */
2188 	if (zone_alloc_bucket(zone, flags)) {
2189 		ZONE_UNLOCK(zone);
2190 		goto zalloc_restart;
2191 	}
2192 	ZONE_UNLOCK(zone);
2193 	/*
2194 	 * We may not be able to get a bucket so return an actual item.
2195 	 */
2196 #ifdef UMA_DEBUG
2197 	printf("uma_zalloc_arg: Bucketzone returned NULL\n");
2198 #endif
2199 
2200 	item = zone_alloc_item(zone, udata, flags);
2201 	return (item);
2202 }
2203 
2204 static uma_slab_t
2205 keg_fetch_slab(uma_keg_t keg, uma_zone_t zone, int flags)
2206 {
2207 	uma_slab_t slab;
2208 
2209 	mtx_assert(&keg->uk_lock, MA_OWNED);
2210 	slab = NULL;
2211 
2212 	for (;;) {
2213 		/*
2214 		 * Find a slab with some space.  Prefer slabs that are partially
2215 		 * used over those that are totally full.  This helps to reduce
2216 		 * fragmentation.
2217 		 */
2218 		if (keg->uk_free != 0) {
2219 			if (!LIST_EMPTY(&keg->uk_part_slab)) {
2220 				slab = LIST_FIRST(&keg->uk_part_slab);
2221 			} else {
2222 				slab = LIST_FIRST(&keg->uk_free_slab);
2223 				LIST_REMOVE(slab, us_link);
2224 				LIST_INSERT_HEAD(&keg->uk_part_slab, slab,
2225 				    us_link);
2226 			}
2227 			MPASS(slab->us_keg == keg);
2228 			return (slab);
2229 		}
2230 
2231 		/*
2232 		 * M_NOVM means don't ask at all!
2233 		 */
2234 		if (flags & M_NOVM)
2235 			break;
2236 
2237 		if (keg->uk_maxpages && keg->uk_pages >= keg->uk_maxpages) {
2238 			keg->uk_flags |= UMA_ZFLAG_FULL;
2239 			/*
2240 			 * If this is not a multi-zone, set the FULL bit.
2241 			 * Otherwise slab_multi() takes care of it.
2242 			 */
2243 			if ((zone->uz_flags & UMA_ZFLAG_MULTI) == 0) {
2244 				zone->uz_flags |= UMA_ZFLAG_FULL;
2245 				zone_log_warning(zone);
2246 			}
2247 			if (flags & M_NOWAIT)
2248 				break;
2249 			zone->uz_sleeps++;
2250 			msleep(keg, &keg->uk_lock, PVM, "keglimit", 0);
2251 			continue;
2252 		}
2253 		keg->uk_recurse++;
2254 		slab = keg_alloc_slab(keg, zone, flags);
2255 		keg->uk_recurse--;
2256 		/*
2257 		 * If we got a slab here it's safe to mark it partially used
2258 		 * and return.  We assume that the caller is going to remove
2259 		 * at least one item.
2260 		 */
2261 		if (slab) {
2262 			MPASS(slab->us_keg == keg);
2263 			LIST_INSERT_HEAD(&keg->uk_part_slab, slab, us_link);
2264 			return (slab);
2265 		}
2266 		/*
2267 		 * We might not have been able to get a slab but another cpu
2268 		 * could have while we were unlocked.  Check again before we
2269 		 * fail.
2270 		 */
2271 		flags |= M_NOVM;
2272 	}
2273 	return (slab);
2274 }
2275 
2276 static inline void
2277 zone_relock(uma_zone_t zone, uma_keg_t keg)
2278 {
2279 	if (zone->uz_lock != &keg->uk_lock) {
2280 		KEG_UNLOCK(keg);
2281 		ZONE_LOCK(zone);
2282 	}
2283 }
2284 
2285 static inline void
2286 keg_relock(uma_keg_t keg, uma_zone_t zone)
2287 {
2288 	if (zone->uz_lock != &keg->uk_lock) {
2289 		ZONE_UNLOCK(zone);
2290 		KEG_LOCK(keg);
2291 	}
2292 }
2293 
2294 static uma_slab_t
2295 zone_fetch_slab(uma_zone_t zone, uma_keg_t keg, int flags)
2296 {
2297 	uma_slab_t slab;
2298 
2299 	if (keg == NULL)
2300 		keg = zone_first_keg(zone);
2301 	/*
2302 	 * This is to prevent us from recursively trying to allocate
2303 	 * buckets.  The problem is that if an allocation forces us to
2304 	 * grab a new bucket we will call page_alloc, which will go off
2305 	 * and cause the vm to allocate vm_map_entries.  If we need new
2306 	 * buckets there too we will recurse in kmem_alloc and bad
2307 	 * things happen.  So instead we return a NULL bucket, and make
2308 	 * the code that allocates buckets smart enough to deal with it
2309 	 */
2310 	if (keg->uk_flags & UMA_ZFLAG_BUCKET && keg->uk_recurse != 0)
2311 		return (NULL);
2312 
2313 	for (;;) {
2314 		slab = keg_fetch_slab(keg, zone, flags);
2315 		if (slab)
2316 			return (slab);
2317 		if (flags & (M_NOWAIT | M_NOVM))
2318 			break;
2319 	}
2320 	return (NULL);
2321 }
2322 
2323 /*
2324  * uma_zone_fetch_slab_multi:  Fetches a slab from one available keg.  Returns
2325  * with the keg locked.  Caller must call zone_relock() afterwards if the
2326  * zone lock is required.  On NULL the zone lock is held.
2327  *
2328  * The last pointer is used to seed the search.  It is not required.
2329  */
2330 static uma_slab_t
2331 zone_fetch_slab_multi(uma_zone_t zone, uma_keg_t last, int rflags)
2332 {
2333 	uma_klink_t klink;
2334 	uma_slab_t slab;
2335 	uma_keg_t keg;
2336 	int flags;
2337 	int empty;
2338 	int full;
2339 
2340 	/*
2341 	 * Don't wait on the first pass.  This will skip limit tests
2342 	 * as well.  We don't want to block if we can find a provider
2343 	 * without blocking.
2344 	 */
2345 	flags = (rflags & ~M_WAITOK) | M_NOWAIT;
2346 	/*
2347 	 * Use the last slab allocated as a hint for where to start
2348 	 * the search.
2349 	 */
2350 	if (last) {
2351 		slab = keg_fetch_slab(last, zone, flags);
2352 		if (slab)
2353 			return (slab);
2354 		zone_relock(zone, last);
2355 		last = NULL;
2356 	}
2357 	/*
2358 	 * Loop until we have a slab incase of transient failures
2359 	 * while M_WAITOK is specified.  I'm not sure this is 100%
2360 	 * required but we've done it for so long now.
2361 	 */
2362 	for (;;) {
2363 		empty = 0;
2364 		full = 0;
2365 		/*
2366 		 * Search the available kegs for slabs.  Be careful to hold the
2367 		 * correct lock while calling into the keg layer.
2368 		 */
2369 		LIST_FOREACH(klink, &zone->uz_kegs, kl_link) {
2370 			keg = klink->kl_keg;
2371 			keg_relock(keg, zone);
2372 			if ((keg->uk_flags & UMA_ZFLAG_FULL) == 0) {
2373 				slab = keg_fetch_slab(keg, zone, flags);
2374 				if (slab)
2375 					return (slab);
2376 			}
2377 			if (keg->uk_flags & UMA_ZFLAG_FULL)
2378 				full++;
2379 			else
2380 				empty++;
2381 			zone_relock(zone, keg);
2382 		}
2383 		if (rflags & (M_NOWAIT | M_NOVM))
2384 			break;
2385 		flags = rflags;
2386 		/*
2387 		 * All kegs are full.  XXX We can't atomically check all kegs
2388 		 * and sleep so just sleep for a short period and retry.
2389 		 */
2390 		if (full && !empty) {
2391 			zone->uz_flags |= UMA_ZFLAG_FULL;
2392 			zone->uz_sleeps++;
2393 			zone_log_warning(zone);
2394 			msleep(zone, zone->uz_lock, PVM, "zonelimit", hz/100);
2395 			zone->uz_flags &= ~UMA_ZFLAG_FULL;
2396 			continue;
2397 		}
2398 	}
2399 	return (NULL);
2400 }
2401 
2402 static void *
2403 slab_alloc_item(uma_zone_t zone, uma_slab_t slab)
2404 {
2405 	uma_keg_t keg;
2406 	uma_slabrefcnt_t slabref;
2407 	void *item;
2408 	uint8_t freei;
2409 
2410 	keg = slab->us_keg;
2411 	mtx_assert(&keg->uk_lock, MA_OWNED);
2412 
2413 	freei = slab->us_firstfree;
2414 	if (keg->uk_flags & UMA_ZONE_REFCNT) {
2415 		slabref = (uma_slabrefcnt_t)slab;
2416 		slab->us_firstfree = slabref->us_freelist[freei].us_item;
2417 	} else {
2418 		slab->us_firstfree = slab->us_freelist[freei].us_item;
2419 	}
2420 	item = slab->us_data + (keg->uk_rsize * freei);
2421 
2422 	slab->us_freecount--;
2423 	keg->uk_free--;
2424 #ifdef INVARIANTS
2425 	uma_dbg_alloc(zone, slab, item);
2426 #endif
2427 	/* Move this slab to the full list */
2428 	if (slab->us_freecount == 0) {
2429 		LIST_REMOVE(slab, us_link);
2430 		LIST_INSERT_HEAD(&keg->uk_full_slab, slab, us_link);
2431 	}
2432 
2433 	return (item);
2434 }
2435 
2436 static int
2437 zone_alloc_bucket(uma_zone_t zone, int flags)
2438 {
2439 	uma_bucket_t bucket;
2440 	uma_slab_t slab;
2441 	uma_keg_t keg;
2442 	int16_t saved;
2443 	int max, origflags = flags;
2444 
2445 	/*
2446 	 * Try this zone's free list first so we don't allocate extra buckets.
2447 	 */
2448 	if ((bucket = LIST_FIRST(&zone->uz_free_bucket)) != NULL) {
2449 		KASSERT(bucket->ub_cnt == 0,
2450 		    ("zone_alloc_bucket: Bucket on free list is not empty."));
2451 		LIST_REMOVE(bucket, ub_link);
2452 	} else {
2453 		int bflags;
2454 
2455 		bflags = (flags & ~M_ZERO);
2456 		if (zone->uz_flags & UMA_ZFLAG_CACHEONLY)
2457 			bflags |= M_NOVM;
2458 
2459 		ZONE_UNLOCK(zone);
2460 		bucket = bucket_alloc(zone->uz_count, bflags);
2461 		ZONE_LOCK(zone);
2462 	}
2463 
2464 	if (bucket == NULL) {
2465 		return (0);
2466 	}
2467 
2468 #ifdef SMP
2469 	/*
2470 	 * This code is here to limit the number of simultaneous bucket fills
2471 	 * for any given zone to the number of per cpu caches in this zone. This
2472 	 * is done so that we don't allocate more memory than we really need.
2473 	 */
2474 	if (zone->uz_fills >= mp_ncpus)
2475 		goto done;
2476 
2477 #endif
2478 	zone->uz_fills++;
2479 
2480 	max = MIN(bucket->ub_entries, zone->uz_count);
2481 	/* Try to keep the buckets totally full */
2482 	saved = bucket->ub_cnt;
2483 	slab = NULL;
2484 	keg = NULL;
2485 	while (bucket->ub_cnt < max &&
2486 	    (slab = zone->uz_slab(zone, keg, flags)) != NULL) {
2487 		keg = slab->us_keg;
2488 		while (slab->us_freecount && bucket->ub_cnt < max) {
2489 			bucket->ub_bucket[bucket->ub_cnt++] =
2490 			    slab_alloc_item(zone, slab);
2491 		}
2492 
2493 		/* Don't block on the next fill */
2494 		flags |= M_NOWAIT;
2495 	}
2496 	if (slab)
2497 		zone_relock(zone, keg);
2498 
2499 	/*
2500 	 * We unlock here because we need to call the zone's init.
2501 	 * It should be safe to unlock because the slab dealt with
2502 	 * above is already on the appropriate list within the keg
2503 	 * and the bucket we filled is not yet on any list, so we
2504 	 * own it.
2505 	 */
2506 	if (zone->uz_init != NULL) {
2507 		int i;
2508 
2509 		ZONE_UNLOCK(zone);
2510 		for (i = saved; i < bucket->ub_cnt; i++)
2511 			if (zone->uz_init(bucket->ub_bucket[i], zone->uz_size,
2512 			    origflags) != 0)
2513 				break;
2514 		/*
2515 		 * If we couldn't initialize the whole bucket, put the
2516 		 * rest back onto the freelist.
2517 		 */
2518 		if (i != bucket->ub_cnt) {
2519 			int j;
2520 
2521 			for (j = i; j < bucket->ub_cnt; j++) {
2522 				zone_free_item(zone, bucket->ub_bucket[j],
2523 				    NULL, SKIP_FINI, 0);
2524 #ifdef INVARIANTS
2525 				bucket->ub_bucket[j] = NULL;
2526 #endif
2527 			}
2528 			bucket->ub_cnt = i;
2529 		}
2530 		ZONE_LOCK(zone);
2531 	}
2532 
2533 	zone->uz_fills--;
2534 	if (bucket->ub_cnt != 0) {
2535 		LIST_INSERT_HEAD(&zone->uz_full_bucket,
2536 		    bucket, ub_link);
2537 		return (1);
2538 	}
2539 #ifdef SMP
2540 done:
2541 #endif
2542 	bucket_free(bucket);
2543 
2544 	return (0);
2545 }
2546 /*
2547  * Allocates an item for an internal zone
2548  *
2549  * Arguments
2550  *	zone   The zone to alloc for.
2551  *	udata  The data to be passed to the constructor.
2552  *	flags  M_WAITOK, M_NOWAIT, M_ZERO.
2553  *
2554  * Returns
2555  *	NULL if there is no memory and M_NOWAIT is set
2556  *	An item if successful
2557  */
2558 
2559 static void *
2560 zone_alloc_item(uma_zone_t zone, void *udata, int flags)
2561 {
2562 	uma_slab_t slab;
2563 	void *item;
2564 
2565 	item = NULL;
2566 
2567 #ifdef UMA_DEBUG_ALLOC
2568 	printf("INTERNAL: Allocating one item from %s(%p)\n", zone->uz_name, zone);
2569 #endif
2570 	ZONE_LOCK(zone);
2571 
2572 	slab = zone->uz_slab(zone, NULL, flags);
2573 	if (slab == NULL) {
2574 		zone->uz_fails++;
2575 		ZONE_UNLOCK(zone);
2576 		return (NULL);
2577 	}
2578 
2579 	item = slab_alloc_item(zone, slab);
2580 
2581 	zone_relock(zone, slab->us_keg);
2582 	zone->uz_allocs++;
2583 	ZONE_UNLOCK(zone);
2584 
2585 	/*
2586 	 * We have to call both the zone's init (not the keg's init)
2587 	 * and the zone's ctor.  This is because the item is going from
2588 	 * a keg slab directly to the user, and the user is expecting it
2589 	 * to be both zone-init'd as well as zone-ctor'd.
2590 	 */
2591 	if (zone->uz_init != NULL) {
2592 		if (zone->uz_init(item, zone->uz_size, flags) != 0) {
2593 			zone_free_item(zone, item, udata, SKIP_FINI,
2594 			    ZFREE_STATFAIL | ZFREE_STATFREE);
2595 			return (NULL);
2596 		}
2597 	}
2598 	if (zone->uz_ctor != NULL) {
2599 		if (zone->uz_ctor(item, zone->uz_size, udata, flags) != 0) {
2600 			zone_free_item(zone, item, udata, SKIP_DTOR,
2601 			    ZFREE_STATFAIL | ZFREE_STATFREE);
2602 			return (NULL);
2603 		}
2604 	}
2605 	if (flags & M_ZERO)
2606 		bzero(item, zone->uz_size);
2607 
2608 	return (item);
2609 }
2610 
2611 /* See uma.h */
2612 void
2613 uma_zfree_arg(uma_zone_t zone, void *item, void *udata)
2614 {
2615 	uma_cache_t cache;
2616 	uma_bucket_t bucket;
2617 	int bflags;
2618 	int cpu;
2619 
2620 #ifdef UMA_DEBUG_ALLOC_1
2621 	printf("Freeing item %p to %s(%p)\n", item, zone->uz_name, zone);
2622 #endif
2623 	CTR2(KTR_UMA, "uma_zfree_arg thread %x zone %s", curthread,
2624 	    zone->uz_name);
2625 
2626         /* uma_zfree(..., NULL) does nothing, to match free(9). */
2627         if (item == NULL)
2628                 return;
2629 #ifdef DEBUG_MEMGUARD
2630 	if (is_memguard_addr(item)) {
2631 		if (zone->uz_dtor != NULL && zone->uz_dtor != mtrash_dtor)
2632 			zone->uz_dtor(item, zone->uz_size, udata);
2633 		if (zone->uz_fini != NULL && zone->uz_fini != mtrash_fini)
2634 			zone->uz_fini(item, zone->uz_size);
2635 		memguard_free(item);
2636 		return;
2637 	}
2638 #endif
2639 	if (zone->uz_dtor)
2640 		zone->uz_dtor(item, zone->uz_size, udata);
2641 
2642 #ifdef INVARIANTS
2643 	ZONE_LOCK(zone);
2644 	if (zone->uz_flags & UMA_ZONE_MALLOC)
2645 		uma_dbg_free(zone, udata, item);
2646 	else
2647 		uma_dbg_free(zone, NULL, item);
2648 	ZONE_UNLOCK(zone);
2649 #endif
2650 	/*
2651 	 * The race here is acceptable.  If we miss it we'll just have to wait
2652 	 * a little longer for the limits to be reset.
2653 	 */
2654 	if (zone->uz_flags & UMA_ZFLAG_FULL)
2655 		goto zfree_internal;
2656 
2657 	/*
2658 	 * If possible, free to the per-CPU cache.  There are two
2659 	 * requirements for safe access to the per-CPU cache: (1) the thread
2660 	 * accessing the cache must not be preempted or yield during access,
2661 	 * and (2) the thread must not migrate CPUs without switching which
2662 	 * cache it accesses.  We rely on a critical section to prevent
2663 	 * preemption and migration.  We release the critical section in
2664 	 * order to acquire the zone mutex if we are unable to free to the
2665 	 * current cache; when we re-acquire the critical section, we must
2666 	 * detect and handle migration if it has occurred.
2667 	 */
2668 zfree_restart:
2669 	critical_enter();
2670 	cpu = curcpu;
2671 	cache = &zone->uz_cpu[cpu];
2672 
2673 zfree_start:
2674 	bucket = cache->uc_freebucket;
2675 
2676 	if (bucket) {
2677 		/*
2678 		 * Do we have room in our bucket? It is OK for this uz count
2679 		 * check to be slightly out of sync.
2680 		 */
2681 
2682 		if (bucket->ub_cnt < bucket->ub_entries) {
2683 			KASSERT(bucket->ub_bucket[bucket->ub_cnt] == NULL,
2684 			    ("uma_zfree: Freeing to non free bucket index."));
2685 			bucket->ub_bucket[bucket->ub_cnt] = item;
2686 			bucket->ub_cnt++;
2687 			cache->uc_frees++;
2688 			critical_exit();
2689 			return;
2690 		} else if (cache->uc_allocbucket) {
2691 #ifdef UMA_DEBUG_ALLOC
2692 			printf("uma_zfree: Swapping buckets.\n");
2693 #endif
2694 			/*
2695 			 * We have run out of space in our freebucket.
2696 			 * See if we can switch with our alloc bucket.
2697 			 */
2698 			if (cache->uc_allocbucket->ub_cnt <
2699 			    cache->uc_freebucket->ub_cnt) {
2700 				bucket = cache->uc_freebucket;
2701 				cache->uc_freebucket = cache->uc_allocbucket;
2702 				cache->uc_allocbucket = bucket;
2703 				goto zfree_start;
2704 			}
2705 		}
2706 	}
2707 	/*
2708 	 * We can get here for two reasons:
2709 	 *
2710 	 * 1) The buckets are NULL
2711 	 * 2) The alloc and free buckets are both somewhat full.
2712 	 *
2713 	 * We must go back the zone, which requires acquiring the zone lock,
2714 	 * which in turn means we must release and re-acquire the critical
2715 	 * section.  Since the critical section is released, we may be
2716 	 * preempted or migrate.  As such, make sure not to maintain any
2717 	 * thread-local state specific to the cache from prior to releasing
2718 	 * the critical section.
2719 	 */
2720 	critical_exit();
2721 	ZONE_LOCK(zone);
2722 	critical_enter();
2723 	cpu = curcpu;
2724 	cache = &zone->uz_cpu[cpu];
2725 	if (cache->uc_freebucket != NULL) {
2726 		if (cache->uc_freebucket->ub_cnt <
2727 		    cache->uc_freebucket->ub_entries) {
2728 			ZONE_UNLOCK(zone);
2729 			goto zfree_start;
2730 		}
2731 		if (cache->uc_allocbucket != NULL &&
2732 		    (cache->uc_allocbucket->ub_cnt <
2733 		    cache->uc_freebucket->ub_cnt)) {
2734 			ZONE_UNLOCK(zone);
2735 			goto zfree_start;
2736 		}
2737 	}
2738 
2739 	/* Since we have locked the zone we may as well send back our stats */
2740 	zone->uz_allocs += cache->uc_allocs;
2741 	cache->uc_allocs = 0;
2742 	zone->uz_frees += cache->uc_frees;
2743 	cache->uc_frees = 0;
2744 
2745 	bucket = cache->uc_freebucket;
2746 	cache->uc_freebucket = NULL;
2747 
2748 	/* Can we throw this on the zone full list? */
2749 	if (bucket != NULL) {
2750 #ifdef UMA_DEBUG_ALLOC
2751 		printf("uma_zfree: Putting old bucket on the free list.\n");
2752 #endif
2753 		/* ub_cnt is pointing to the last free item */
2754 		KASSERT(bucket->ub_cnt != 0,
2755 		    ("uma_zfree: Attempting to insert an empty bucket onto the full list.\n"));
2756 		LIST_INSERT_HEAD(&zone->uz_full_bucket,
2757 		    bucket, ub_link);
2758 	}
2759 	if ((bucket = LIST_FIRST(&zone->uz_free_bucket)) != NULL) {
2760 		LIST_REMOVE(bucket, ub_link);
2761 		ZONE_UNLOCK(zone);
2762 		cache->uc_freebucket = bucket;
2763 		goto zfree_start;
2764 	}
2765 	/* We are no longer associated with this CPU. */
2766 	critical_exit();
2767 
2768 	/* And the zone.. */
2769 	ZONE_UNLOCK(zone);
2770 
2771 #ifdef UMA_DEBUG_ALLOC
2772 	printf("uma_zfree: Allocating new free bucket.\n");
2773 #endif
2774 	bflags = M_NOWAIT;
2775 
2776 	if (zone->uz_flags & UMA_ZFLAG_CACHEONLY)
2777 		bflags |= M_NOVM;
2778 	bucket = bucket_alloc(zone->uz_count, bflags);
2779 	if (bucket) {
2780 		ZONE_LOCK(zone);
2781 		LIST_INSERT_HEAD(&zone->uz_free_bucket,
2782 		    bucket, ub_link);
2783 		ZONE_UNLOCK(zone);
2784 		goto zfree_restart;
2785 	}
2786 
2787 	/*
2788 	 * If nothing else caught this, we'll just do an internal free.
2789 	 */
2790 zfree_internal:
2791 	zone_free_item(zone, item, udata, SKIP_DTOR, ZFREE_STATFREE);
2792 
2793 	return;
2794 }
2795 
2796 /*
2797  * Frees an item to an INTERNAL zone or allocates a free bucket
2798  *
2799  * Arguments:
2800  *	zone   The zone to free to
2801  *	item   The item we're freeing
2802  *	udata  User supplied data for the dtor
2803  *	skip   Skip dtors and finis
2804  */
2805 static void
2806 zone_free_item(uma_zone_t zone, void *item, void *udata,
2807     enum zfreeskip skip, int flags)
2808 {
2809 	uma_slab_t slab;
2810 	uma_slabrefcnt_t slabref;
2811 	uma_keg_t keg;
2812 	uint8_t *mem;
2813 	uint8_t freei;
2814 	int clearfull;
2815 
2816 	if (skip < SKIP_DTOR && zone->uz_dtor)
2817 		zone->uz_dtor(item, zone->uz_size, udata);
2818 
2819 	if (skip < SKIP_FINI && zone->uz_fini)
2820 		zone->uz_fini(item, zone->uz_size);
2821 
2822 	ZONE_LOCK(zone);
2823 
2824 	if (flags & ZFREE_STATFAIL)
2825 		zone->uz_fails++;
2826 	if (flags & ZFREE_STATFREE)
2827 		zone->uz_frees++;
2828 
2829 	if (!(zone->uz_flags & UMA_ZONE_VTOSLAB)) {
2830 		mem = (uint8_t *)((unsigned long)item & (~UMA_SLAB_MASK));
2831 		keg = zone_first_keg(zone); /* Must only be one. */
2832 		if (zone->uz_flags & UMA_ZONE_HASH) {
2833 			slab = hash_sfind(&keg->uk_hash, mem);
2834 		} else {
2835 			mem += keg->uk_pgoff;
2836 			slab = (uma_slab_t)mem;
2837 		}
2838 	} else {
2839 		/* This prevents redundant lookups via free(). */
2840 		if ((zone->uz_flags & UMA_ZONE_MALLOC) && udata != NULL)
2841 			slab = (uma_slab_t)udata;
2842 		else
2843 			slab = vtoslab((vm_offset_t)item);
2844 		keg = slab->us_keg;
2845 		keg_relock(keg, zone);
2846 	}
2847 	MPASS(keg == slab->us_keg);
2848 
2849 	/* Do we need to remove from any lists? */
2850 	if (slab->us_freecount+1 == keg->uk_ipers) {
2851 		LIST_REMOVE(slab, us_link);
2852 		LIST_INSERT_HEAD(&keg->uk_free_slab, slab, us_link);
2853 	} else if (slab->us_freecount == 0) {
2854 		LIST_REMOVE(slab, us_link);
2855 		LIST_INSERT_HEAD(&keg->uk_part_slab, slab, us_link);
2856 	}
2857 
2858 	/* Slab management stuff */
2859 	freei = ((unsigned long)item - (unsigned long)slab->us_data)
2860 		/ keg->uk_rsize;
2861 
2862 #ifdef INVARIANTS
2863 	if (!skip)
2864 		uma_dbg_free(zone, slab, item);
2865 #endif
2866 
2867 	if (keg->uk_flags & UMA_ZONE_REFCNT) {
2868 		slabref = (uma_slabrefcnt_t)slab;
2869 		slabref->us_freelist[freei].us_item = slab->us_firstfree;
2870 	} else {
2871 		slab->us_freelist[freei].us_item = slab->us_firstfree;
2872 	}
2873 	slab->us_firstfree = freei;
2874 	slab->us_freecount++;
2875 
2876 	/* Zone statistics */
2877 	keg->uk_free++;
2878 
2879 	clearfull = 0;
2880 	if (keg->uk_flags & UMA_ZFLAG_FULL) {
2881 		if (keg->uk_pages < keg->uk_maxpages) {
2882 			keg->uk_flags &= ~UMA_ZFLAG_FULL;
2883 			clearfull = 1;
2884 		}
2885 
2886 		/*
2887 		 * We can handle one more allocation. Since we're clearing ZFLAG_FULL,
2888 		 * wake up all procs blocked on pages. This should be uncommon, so
2889 		 * keeping this simple for now (rather than adding count of blocked
2890 		 * threads etc).
2891 		 */
2892 		wakeup(keg);
2893 	}
2894 	if (clearfull) {
2895 		zone_relock(zone, keg);
2896 		zone->uz_flags &= ~UMA_ZFLAG_FULL;
2897 		wakeup(zone);
2898 		ZONE_UNLOCK(zone);
2899 	} else
2900 		KEG_UNLOCK(keg);
2901 }
2902 
2903 /* See uma.h */
2904 int
2905 uma_zone_set_max(uma_zone_t zone, int nitems)
2906 {
2907 	uma_keg_t keg;
2908 
2909 	ZONE_LOCK(zone);
2910 	keg = zone_first_keg(zone);
2911 	keg->uk_maxpages = (nitems / keg->uk_ipers) * keg->uk_ppera;
2912 	if (keg->uk_maxpages * keg->uk_ipers < nitems)
2913 		keg->uk_maxpages += keg->uk_ppera;
2914 	nitems = keg->uk_maxpages * keg->uk_ipers;
2915 	ZONE_UNLOCK(zone);
2916 
2917 	return (nitems);
2918 }
2919 
2920 /* See uma.h */
2921 int
2922 uma_zone_get_max(uma_zone_t zone)
2923 {
2924 	int nitems;
2925 	uma_keg_t keg;
2926 
2927 	ZONE_LOCK(zone);
2928 	keg = zone_first_keg(zone);
2929 	nitems = keg->uk_maxpages * keg->uk_ipers;
2930 	ZONE_UNLOCK(zone);
2931 
2932 	return (nitems);
2933 }
2934 
2935 /* See uma.h */
2936 void
2937 uma_zone_set_warning(uma_zone_t zone, const char *warning)
2938 {
2939 
2940 	ZONE_LOCK(zone);
2941 	zone->uz_warning = warning;
2942 	ZONE_UNLOCK(zone);
2943 }
2944 
2945 /* See uma.h */
2946 int
2947 uma_zone_get_cur(uma_zone_t zone)
2948 {
2949 	int64_t nitems;
2950 	u_int i;
2951 
2952 	ZONE_LOCK(zone);
2953 	nitems = zone->uz_allocs - zone->uz_frees;
2954 	CPU_FOREACH(i) {
2955 		/*
2956 		 * See the comment in sysctl_vm_zone_stats() regarding the
2957 		 * safety of accessing the per-cpu caches. With the zone lock
2958 		 * held, it is safe, but can potentially result in stale data.
2959 		 */
2960 		nitems += zone->uz_cpu[i].uc_allocs -
2961 		    zone->uz_cpu[i].uc_frees;
2962 	}
2963 	ZONE_UNLOCK(zone);
2964 
2965 	return (nitems < 0 ? 0 : nitems);
2966 }
2967 
2968 /* See uma.h */
2969 void
2970 uma_zone_set_init(uma_zone_t zone, uma_init uminit)
2971 {
2972 	uma_keg_t keg;
2973 
2974 	ZONE_LOCK(zone);
2975 	keg = zone_first_keg(zone);
2976 	KASSERT(keg->uk_pages == 0,
2977 	    ("uma_zone_set_init on non-empty keg"));
2978 	keg->uk_init = uminit;
2979 	ZONE_UNLOCK(zone);
2980 }
2981 
2982 /* See uma.h */
2983 void
2984 uma_zone_set_fini(uma_zone_t zone, uma_fini fini)
2985 {
2986 	uma_keg_t keg;
2987 
2988 	ZONE_LOCK(zone);
2989 	keg = zone_first_keg(zone);
2990 	KASSERT(keg->uk_pages == 0,
2991 	    ("uma_zone_set_fini on non-empty keg"));
2992 	keg->uk_fini = fini;
2993 	ZONE_UNLOCK(zone);
2994 }
2995 
2996 /* See uma.h */
2997 void
2998 uma_zone_set_zinit(uma_zone_t zone, uma_init zinit)
2999 {
3000 	ZONE_LOCK(zone);
3001 	KASSERT(zone_first_keg(zone)->uk_pages == 0,
3002 	    ("uma_zone_set_zinit on non-empty keg"));
3003 	zone->uz_init = zinit;
3004 	ZONE_UNLOCK(zone);
3005 }
3006 
3007 /* See uma.h */
3008 void
3009 uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini)
3010 {
3011 	ZONE_LOCK(zone);
3012 	KASSERT(zone_first_keg(zone)->uk_pages == 0,
3013 	    ("uma_zone_set_zfini on non-empty keg"));
3014 	zone->uz_fini = zfini;
3015 	ZONE_UNLOCK(zone);
3016 }
3017 
3018 /* See uma.h */
3019 /* XXX uk_freef is not actually used with the zone locked */
3020 void
3021 uma_zone_set_freef(uma_zone_t zone, uma_free freef)
3022 {
3023 
3024 	ZONE_LOCK(zone);
3025 	zone_first_keg(zone)->uk_freef = freef;
3026 	ZONE_UNLOCK(zone);
3027 }
3028 
3029 /* See uma.h */
3030 /* XXX uk_allocf is not actually used with the zone locked */
3031 void
3032 uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf)
3033 {
3034 	uma_keg_t keg;
3035 
3036 	ZONE_LOCK(zone);
3037 	keg = zone_first_keg(zone);
3038 	keg->uk_flags |= UMA_ZFLAG_PRIVALLOC;
3039 	keg->uk_allocf = allocf;
3040 	ZONE_UNLOCK(zone);
3041 }
3042 
3043 /* See uma.h */
3044 int
3045 uma_zone_reserve_kva(uma_zone_t zone, int count)
3046 {
3047 	uma_keg_t keg;
3048 	vm_offset_t kva;
3049 	int pages;
3050 
3051 	keg = zone_first_keg(zone);
3052 	pages = count / keg->uk_ipers;
3053 
3054 	if (pages * keg->uk_ipers < count)
3055 		pages++;
3056 
3057 #ifdef UMA_MD_SMALL_ALLOC
3058 	if (keg->uk_ppera > 1) {
3059 #else
3060 	if (1) {
3061 #endif
3062 		kva = kmem_alloc_nofault(kernel_map, pages * UMA_SLAB_SIZE);
3063 		if (kva == 0)
3064 			return (0);
3065 	} else
3066 		kva = 0;
3067 	ZONE_LOCK(zone);
3068 	keg->uk_kva = kva;
3069 	keg->uk_offset = 0;
3070 	keg->uk_maxpages = pages;
3071 #ifdef UMA_MD_SMALL_ALLOC
3072 	keg->uk_allocf = (keg->uk_ppera > 1) ? noobj_alloc : uma_small_alloc;
3073 #else
3074 	keg->uk_allocf = noobj_alloc;
3075 #endif
3076 	keg->uk_flags |= UMA_ZONE_NOFREE | UMA_ZFLAG_PRIVALLOC;
3077 	ZONE_UNLOCK(zone);
3078 	return (1);
3079 }
3080 
3081 /* See uma.h */
3082 void
3083 uma_prealloc(uma_zone_t zone, int items)
3084 {
3085 	int slabs;
3086 	uma_slab_t slab;
3087 	uma_keg_t keg;
3088 
3089 	keg = zone_first_keg(zone);
3090 	ZONE_LOCK(zone);
3091 	slabs = items / keg->uk_ipers;
3092 	if (slabs * keg->uk_ipers < items)
3093 		slabs++;
3094 	while (slabs > 0) {
3095 		slab = keg_alloc_slab(keg, zone, M_WAITOK);
3096 		if (slab == NULL)
3097 			break;
3098 		MPASS(slab->us_keg == keg);
3099 		LIST_INSERT_HEAD(&keg->uk_free_slab, slab, us_link);
3100 		slabs--;
3101 	}
3102 	ZONE_UNLOCK(zone);
3103 }
3104 
3105 /* See uma.h */
3106 uint32_t *
3107 uma_find_refcnt(uma_zone_t zone, void *item)
3108 {
3109 	uma_slabrefcnt_t slabref;
3110 	uma_keg_t keg;
3111 	uint32_t *refcnt;
3112 	int idx;
3113 
3114 	slabref = (uma_slabrefcnt_t)vtoslab((vm_offset_t)item &
3115 	    (~UMA_SLAB_MASK));
3116 	keg = slabref->us_keg;
3117 	KASSERT(slabref != NULL && slabref->us_keg->uk_flags & UMA_ZONE_REFCNT,
3118 	    ("uma_find_refcnt(): zone possibly not UMA_ZONE_REFCNT"));
3119 	idx = ((unsigned long)item - (unsigned long)slabref->us_data)
3120 	    / keg->uk_rsize;
3121 	refcnt = &slabref->us_freelist[idx].us_refcnt;
3122 	return refcnt;
3123 }
3124 
3125 /* See uma.h */
3126 void
3127 uma_reclaim(void)
3128 {
3129 #ifdef UMA_DEBUG
3130 	printf("UMA: vm asked us to release pages!\n");
3131 #endif
3132 	bucket_enable();
3133 	zone_foreach(zone_drain);
3134 	/*
3135 	 * Some slabs may have been freed but this zone will be visited early
3136 	 * we visit again so that we can free pages that are empty once other
3137 	 * zones are drained.  We have to do the same for buckets.
3138 	 */
3139 	zone_drain(slabzone);
3140 	zone_drain(slabrefzone);
3141 	bucket_zone_drain();
3142 }
3143 
3144 /* See uma.h */
3145 int
3146 uma_zone_exhausted(uma_zone_t zone)
3147 {
3148 	int full;
3149 
3150 	ZONE_LOCK(zone);
3151 	full = (zone->uz_flags & UMA_ZFLAG_FULL);
3152 	ZONE_UNLOCK(zone);
3153 	return (full);
3154 }
3155 
3156 int
3157 uma_zone_exhausted_nolock(uma_zone_t zone)
3158 {
3159 	return (zone->uz_flags & UMA_ZFLAG_FULL);
3160 }
3161 
3162 void *
3163 uma_large_malloc(int size, int wait)
3164 {
3165 	void *mem;
3166 	uma_slab_t slab;
3167 	uint8_t flags;
3168 
3169 	slab = zone_alloc_item(slabzone, NULL, wait);
3170 	if (slab == NULL)
3171 		return (NULL);
3172 	mem = page_alloc(NULL, size, &flags, wait);
3173 	if (mem) {
3174 		vsetslab((vm_offset_t)mem, slab);
3175 		slab->us_data = mem;
3176 		slab->us_flags = flags | UMA_SLAB_MALLOC;
3177 		slab->us_size = size;
3178 	} else {
3179 		zone_free_item(slabzone, slab, NULL, SKIP_NONE,
3180 		    ZFREE_STATFAIL | ZFREE_STATFREE);
3181 	}
3182 
3183 	return (mem);
3184 }
3185 
3186 void
3187 uma_large_free(uma_slab_t slab)
3188 {
3189 	vsetobj((vm_offset_t)slab->us_data, kmem_object);
3190 	page_free(slab->us_data, slab->us_size, slab->us_flags);
3191 	zone_free_item(slabzone, slab, NULL, SKIP_NONE, ZFREE_STATFREE);
3192 }
3193 
3194 void
3195 uma_print_stats(void)
3196 {
3197 	zone_foreach(uma_print_zone);
3198 }
3199 
3200 static void
3201 slab_print(uma_slab_t slab)
3202 {
3203 	printf("slab: keg %p, data %p, freecount %d, firstfree %d\n",
3204 		slab->us_keg, slab->us_data, slab->us_freecount,
3205 		slab->us_firstfree);
3206 }
3207 
3208 static void
3209 cache_print(uma_cache_t cache)
3210 {
3211 	printf("alloc: %p(%d), free: %p(%d)\n",
3212 		cache->uc_allocbucket,
3213 		cache->uc_allocbucket?cache->uc_allocbucket->ub_cnt:0,
3214 		cache->uc_freebucket,
3215 		cache->uc_freebucket?cache->uc_freebucket->ub_cnt:0);
3216 }
3217 
3218 static void
3219 uma_print_keg(uma_keg_t keg)
3220 {
3221 	uma_slab_t slab;
3222 
3223 	printf("keg: %s(%p) size %d(%d) flags %#x ipers %d ppera %d "
3224 	    "out %d free %d limit %d\n",
3225 	    keg->uk_name, keg, keg->uk_size, keg->uk_rsize, keg->uk_flags,
3226 	    keg->uk_ipers, keg->uk_ppera,
3227 	    (keg->uk_ipers * keg->uk_pages) - keg->uk_free, keg->uk_free,
3228 	    (keg->uk_maxpages / keg->uk_ppera) * keg->uk_ipers);
3229 	printf("Part slabs:\n");
3230 	LIST_FOREACH(slab, &keg->uk_part_slab, us_link)
3231 		slab_print(slab);
3232 	printf("Free slabs:\n");
3233 	LIST_FOREACH(slab, &keg->uk_free_slab, us_link)
3234 		slab_print(slab);
3235 	printf("Full slabs:\n");
3236 	LIST_FOREACH(slab, &keg->uk_full_slab, us_link)
3237 		slab_print(slab);
3238 }
3239 
3240 void
3241 uma_print_zone(uma_zone_t zone)
3242 {
3243 	uma_cache_t cache;
3244 	uma_klink_t kl;
3245 	int i;
3246 
3247 	printf("zone: %s(%p) size %d flags %#x\n",
3248 	    zone->uz_name, zone, zone->uz_size, zone->uz_flags);
3249 	LIST_FOREACH(kl, &zone->uz_kegs, kl_link)
3250 		uma_print_keg(kl->kl_keg);
3251 	CPU_FOREACH(i) {
3252 		cache = &zone->uz_cpu[i];
3253 		printf("CPU %d Cache:\n", i);
3254 		cache_print(cache);
3255 	}
3256 }
3257 
3258 #ifdef DDB
3259 /*
3260  * Generate statistics across both the zone and its per-cpu cache's.  Return
3261  * desired statistics if the pointer is non-NULL for that statistic.
3262  *
3263  * Note: does not update the zone statistics, as it can't safely clear the
3264  * per-CPU cache statistic.
3265  *
3266  * XXXRW: Following the uc_allocbucket and uc_freebucket pointers here isn't
3267  * safe from off-CPU; we should modify the caches to track this information
3268  * directly so that we don't have to.
3269  */
3270 static void
3271 uma_zone_sumstat(uma_zone_t z, int *cachefreep, uint64_t *allocsp,
3272     uint64_t *freesp, uint64_t *sleepsp)
3273 {
3274 	uma_cache_t cache;
3275 	uint64_t allocs, frees, sleeps;
3276 	int cachefree, cpu;
3277 
3278 	allocs = frees = sleeps = 0;
3279 	cachefree = 0;
3280 	CPU_FOREACH(cpu) {
3281 		cache = &z->uz_cpu[cpu];
3282 		if (cache->uc_allocbucket != NULL)
3283 			cachefree += cache->uc_allocbucket->ub_cnt;
3284 		if (cache->uc_freebucket != NULL)
3285 			cachefree += cache->uc_freebucket->ub_cnt;
3286 		allocs += cache->uc_allocs;
3287 		frees += cache->uc_frees;
3288 	}
3289 	allocs += z->uz_allocs;
3290 	frees += z->uz_frees;
3291 	sleeps += z->uz_sleeps;
3292 	if (cachefreep != NULL)
3293 		*cachefreep = cachefree;
3294 	if (allocsp != NULL)
3295 		*allocsp = allocs;
3296 	if (freesp != NULL)
3297 		*freesp = frees;
3298 	if (sleepsp != NULL)
3299 		*sleepsp = sleeps;
3300 }
3301 #endif /* DDB */
3302 
3303 static int
3304 sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS)
3305 {
3306 	uma_keg_t kz;
3307 	uma_zone_t z;
3308 	int count;
3309 
3310 	count = 0;
3311 	mtx_lock(&uma_mtx);
3312 	LIST_FOREACH(kz, &uma_kegs, uk_link) {
3313 		LIST_FOREACH(z, &kz->uk_zones, uz_link)
3314 			count++;
3315 	}
3316 	mtx_unlock(&uma_mtx);
3317 	return (sysctl_handle_int(oidp, &count, 0, req));
3318 }
3319 
3320 static int
3321 sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS)
3322 {
3323 	struct uma_stream_header ush;
3324 	struct uma_type_header uth;
3325 	struct uma_percpu_stat ups;
3326 	uma_bucket_t bucket;
3327 	struct sbuf sbuf;
3328 	uma_cache_t cache;
3329 	uma_klink_t kl;
3330 	uma_keg_t kz;
3331 	uma_zone_t z;
3332 	uma_keg_t k;
3333 	int count, error, i;
3334 
3335 	error = sysctl_wire_old_buffer(req, 0);
3336 	if (error != 0)
3337 		return (error);
3338 	sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
3339 
3340 	count = 0;
3341 	mtx_lock(&uma_mtx);
3342 	LIST_FOREACH(kz, &uma_kegs, uk_link) {
3343 		LIST_FOREACH(z, &kz->uk_zones, uz_link)
3344 			count++;
3345 	}
3346 
3347 	/*
3348 	 * Insert stream header.
3349 	 */
3350 	bzero(&ush, sizeof(ush));
3351 	ush.ush_version = UMA_STREAM_VERSION;
3352 	ush.ush_maxcpus = (mp_maxid + 1);
3353 	ush.ush_count = count;
3354 	(void)sbuf_bcat(&sbuf, &ush, sizeof(ush));
3355 
3356 	LIST_FOREACH(kz, &uma_kegs, uk_link) {
3357 		LIST_FOREACH(z, &kz->uk_zones, uz_link) {
3358 			bzero(&uth, sizeof(uth));
3359 			ZONE_LOCK(z);
3360 			strlcpy(uth.uth_name, z->uz_name, UTH_MAX_NAME);
3361 			uth.uth_align = kz->uk_align;
3362 			uth.uth_size = kz->uk_size;
3363 			uth.uth_rsize = kz->uk_rsize;
3364 			LIST_FOREACH(kl, &z->uz_kegs, kl_link) {
3365 				k = kl->kl_keg;
3366 				uth.uth_maxpages += k->uk_maxpages;
3367 				uth.uth_pages += k->uk_pages;
3368 				uth.uth_keg_free += k->uk_free;
3369 				uth.uth_limit = (k->uk_maxpages / k->uk_ppera)
3370 				    * k->uk_ipers;
3371 			}
3372 
3373 			/*
3374 			 * A zone is secondary is it is not the first entry
3375 			 * on the keg's zone list.
3376 			 */
3377 			if ((z->uz_flags & UMA_ZONE_SECONDARY) &&
3378 			    (LIST_FIRST(&kz->uk_zones) != z))
3379 				uth.uth_zone_flags = UTH_ZONE_SECONDARY;
3380 
3381 			LIST_FOREACH(bucket, &z->uz_full_bucket, ub_link)
3382 				uth.uth_zone_free += bucket->ub_cnt;
3383 			uth.uth_allocs = z->uz_allocs;
3384 			uth.uth_frees = z->uz_frees;
3385 			uth.uth_fails = z->uz_fails;
3386 			uth.uth_sleeps = z->uz_sleeps;
3387 			(void)sbuf_bcat(&sbuf, &uth, sizeof(uth));
3388 			/*
3389 			 * While it is not normally safe to access the cache
3390 			 * bucket pointers while not on the CPU that owns the
3391 			 * cache, we only allow the pointers to be exchanged
3392 			 * without the zone lock held, not invalidated, so
3393 			 * accept the possible race associated with bucket
3394 			 * exchange during monitoring.
3395 			 */
3396 			for (i = 0; i < (mp_maxid + 1); i++) {
3397 				bzero(&ups, sizeof(ups));
3398 				if (kz->uk_flags & UMA_ZFLAG_INTERNAL)
3399 					goto skip;
3400 				if (CPU_ABSENT(i))
3401 					goto skip;
3402 				cache = &z->uz_cpu[i];
3403 				if (cache->uc_allocbucket != NULL)
3404 					ups.ups_cache_free +=
3405 					    cache->uc_allocbucket->ub_cnt;
3406 				if (cache->uc_freebucket != NULL)
3407 					ups.ups_cache_free +=
3408 					    cache->uc_freebucket->ub_cnt;
3409 				ups.ups_allocs = cache->uc_allocs;
3410 				ups.ups_frees = cache->uc_frees;
3411 skip:
3412 				(void)sbuf_bcat(&sbuf, &ups, sizeof(ups));
3413 			}
3414 			ZONE_UNLOCK(z);
3415 		}
3416 	}
3417 	mtx_unlock(&uma_mtx);
3418 	error = sbuf_finish(&sbuf);
3419 	sbuf_delete(&sbuf);
3420 	return (error);
3421 }
3422 
3423 #ifdef DDB
3424 DB_SHOW_COMMAND(uma, db_show_uma)
3425 {
3426 	uint64_t allocs, frees, sleeps;
3427 	uma_bucket_t bucket;
3428 	uma_keg_t kz;
3429 	uma_zone_t z;
3430 	int cachefree;
3431 
3432 	db_printf("%18s %8s %8s %8s %12s %8s\n", "Zone", "Size", "Used", "Free",
3433 	    "Requests", "Sleeps");
3434 	LIST_FOREACH(kz, &uma_kegs, uk_link) {
3435 		LIST_FOREACH(z, &kz->uk_zones, uz_link) {
3436 			if (kz->uk_flags & UMA_ZFLAG_INTERNAL) {
3437 				allocs = z->uz_allocs;
3438 				frees = z->uz_frees;
3439 				sleeps = z->uz_sleeps;
3440 				cachefree = 0;
3441 			} else
3442 				uma_zone_sumstat(z, &cachefree, &allocs,
3443 				    &frees, &sleeps);
3444 			if (!((z->uz_flags & UMA_ZONE_SECONDARY) &&
3445 			    (LIST_FIRST(&kz->uk_zones) != z)))
3446 				cachefree += kz->uk_free;
3447 			LIST_FOREACH(bucket, &z->uz_full_bucket, ub_link)
3448 				cachefree += bucket->ub_cnt;
3449 			db_printf("%18s %8ju %8jd %8d %12ju %8ju\n", z->uz_name,
3450 			    (uintmax_t)kz->uk_size,
3451 			    (intmax_t)(allocs - frees), cachefree,
3452 			    (uintmax_t)allocs, sleeps);
3453 			if (db_pager_quit)
3454 				return;
3455 		}
3456 	}
3457 }
3458 #endif
3459