xref: /freebsd/sys/vm/uma_core.c (revision 137a344c6341d1469432e9deb3a25593f96672ad)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2002-2005, 2009, 2013 Jeffrey Roberson <jeff@FreeBSD.org>
5  * Copyright (c) 2004, 2005 Bosko Milekic <bmilekic@FreeBSD.org>
6  * Copyright (c) 2004-2006 Robert N. M. Watson
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice unmodified, this list of conditions, and the following
14  *    disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 /*
32  * uma_core.c  Implementation of the Universal Memory allocator
33  *
34  * This allocator is intended to replace the multitude of similar object caches
35  * in the standard FreeBSD kernel.  The intent is to be flexible as well as
36  * efficient.  A primary design goal is to return unused memory to the rest of
37  * the system.  This will make the system as a whole more flexible due to the
38  * ability to move memory to subsystems which most need it instead of leaving
39  * pools of reserved memory unused.
40  *
41  * The basic ideas stem from similar slab/zone based allocators whose algorithms
42  * are well known.
43  *
44  */
45 
46 /*
47  * TODO:
48  *	- Improve memory usage for large allocations
49  *	- Investigate cache size adjustments
50  */
51 
52 #include <sys/cdefs.h>
53 __FBSDID("$FreeBSD$");
54 
55 #include "opt_ddb.h"
56 #include "opt_param.h"
57 #include "opt_vm.h"
58 
59 #include <sys/param.h>
60 #include <sys/systm.h>
61 #include <sys/bitset.h>
62 #include <sys/eventhandler.h>
63 #include <sys/kernel.h>
64 #include <sys/types.h>
65 #include <sys/limits.h>
66 #include <sys/queue.h>
67 #include <sys/malloc.h>
68 #include <sys/ktr.h>
69 #include <sys/lock.h>
70 #include <sys/sysctl.h>
71 #include <sys/mutex.h>
72 #include <sys/proc.h>
73 #include <sys/random.h>
74 #include <sys/rwlock.h>
75 #include <sys/sbuf.h>
76 #include <sys/sched.h>
77 #include <sys/smp.h>
78 #include <sys/taskqueue.h>
79 #include <sys/vmmeter.h>
80 
81 #include <vm/vm.h>
82 #include <vm/vm_object.h>
83 #include <vm/vm_page.h>
84 #include <vm/vm_pageout.h>
85 #include <vm/vm_param.h>
86 #include <vm/vm_phys.h>
87 #include <vm/vm_map.h>
88 #include <vm/vm_kern.h>
89 #include <vm/vm_extern.h>
90 #include <vm/uma.h>
91 #include <vm/uma_int.h>
92 #include <vm/uma_dbg.h>
93 
94 #include <ddb/ddb.h>
95 
96 #ifdef DEBUG_MEMGUARD
97 #include <vm/memguard.h>
98 #endif
99 
100 /*
101  * This is the zone and keg from which all zones are spawned.
102  */
103 static uma_zone_t kegs;
104 static uma_zone_t zones;
105 
106 /* This is the zone from which all offpage uma_slab_ts are allocated. */
107 static uma_zone_t slabzone;
108 
109 /*
110  * The initial hash tables come out of this zone so they can be allocated
111  * prior to malloc coming up.
112  */
113 static uma_zone_t hashzone;
114 
115 /* The boot-time adjusted value for cache line alignment. */
116 int uma_align_cache = 64 - 1;
117 
118 static MALLOC_DEFINE(M_UMAHASH, "UMAHash", "UMA Hash Buckets");
119 
120 /*
121  * Are we allowed to allocate buckets?
122  */
123 static int bucketdisable = 1;
124 
125 /* Linked list of all kegs in the system */
126 static LIST_HEAD(,uma_keg) uma_kegs = LIST_HEAD_INITIALIZER(uma_kegs);
127 
128 /* Linked list of all cache-only zones in the system */
129 static LIST_HEAD(,uma_zone) uma_cachezones =
130     LIST_HEAD_INITIALIZER(uma_cachezones);
131 
132 /* This RW lock protects the keg list */
133 static struct rwlock_padalign __exclusive_cache_line uma_rwlock;
134 
135 /*
136  * Pointer and counter to pool of pages, that is preallocated at
137  * startup to bootstrap UMA.  Early zones continue to use the pool
138  * until it is depleted, so allocations may happen after boot, thus
139  * we need a mutex to protect it.
140  */
141 static char *bootmem;
142 static int boot_pages;
143 static struct mtx uma_boot_pages_mtx;
144 
145 static struct sx uma_drain_lock;
146 
147 /* kmem soft limit. */
148 static unsigned long uma_kmem_limit = LONG_MAX;
149 static volatile unsigned long uma_kmem_total;
150 
151 /* Is the VM done starting up? */
152 static int booted = 0;
153 #define	UMA_STARTUP	1
154 #define	UMA_STARTUP2	2
155 
156 /*
157  * This is the handle used to schedule events that need to happen
158  * outside of the allocation fast path.
159  */
160 static struct callout uma_callout;
161 #define	UMA_TIMEOUT	20		/* Seconds for callout interval. */
162 
163 /*
164  * This structure is passed as the zone ctor arg so that I don't have to create
165  * a special allocation function just for zones.
166  */
167 struct uma_zctor_args {
168 	const char *name;
169 	size_t size;
170 	uma_ctor ctor;
171 	uma_dtor dtor;
172 	uma_init uminit;
173 	uma_fini fini;
174 	uma_import import;
175 	uma_release release;
176 	void *arg;
177 	uma_keg_t keg;
178 	int align;
179 	uint32_t flags;
180 };
181 
182 struct uma_kctor_args {
183 	uma_zone_t zone;
184 	size_t size;
185 	uma_init uminit;
186 	uma_fini fini;
187 	int align;
188 	uint32_t flags;
189 };
190 
191 struct uma_bucket_zone {
192 	uma_zone_t	ubz_zone;
193 	char		*ubz_name;
194 	int		ubz_entries;	/* Number of items it can hold. */
195 	int		ubz_maxsize;	/* Maximum allocation size per-item. */
196 };
197 
198 /*
199  * Compute the actual number of bucket entries to pack them in power
200  * of two sizes for more efficient space utilization.
201  */
202 #define	BUCKET_SIZE(n)						\
203     (((sizeof(void *) * (n)) - sizeof(struct uma_bucket)) / sizeof(void *))
204 
205 #define	BUCKET_MAX	BUCKET_SIZE(256)
206 
207 struct uma_bucket_zone bucket_zones[] = {
208 	{ NULL, "4 Bucket", BUCKET_SIZE(4), 4096 },
209 	{ NULL, "6 Bucket", BUCKET_SIZE(6), 3072 },
210 	{ NULL, "8 Bucket", BUCKET_SIZE(8), 2048 },
211 	{ NULL, "12 Bucket", BUCKET_SIZE(12), 1536 },
212 	{ NULL, "16 Bucket", BUCKET_SIZE(16), 1024 },
213 	{ NULL, "32 Bucket", BUCKET_SIZE(32), 512 },
214 	{ NULL, "64 Bucket", BUCKET_SIZE(64), 256 },
215 	{ NULL, "128 Bucket", BUCKET_SIZE(128), 128 },
216 	{ NULL, "256 Bucket", BUCKET_SIZE(256), 64 },
217 	{ NULL, NULL, 0}
218 };
219 
220 /*
221  * Flags and enumerations to be passed to internal functions.
222  */
223 enum zfreeskip { SKIP_NONE = 0, SKIP_DTOR, SKIP_FINI };
224 
225 #define	UMA_ANYDOMAIN	-1	/* Special value for domain search. */
226 
227 /* Prototypes.. */
228 
229 static void *noobj_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
230 static void *page_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
231 static void *startup_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
232 static void page_free(void *, vm_size_t, uint8_t);
233 static uma_slab_t keg_alloc_slab(uma_keg_t, uma_zone_t, int, int);
234 static void cache_drain(uma_zone_t);
235 static void bucket_drain(uma_zone_t, uma_bucket_t);
236 static void bucket_cache_drain(uma_zone_t zone);
237 static int keg_ctor(void *, int, void *, int);
238 static void keg_dtor(void *, int, void *);
239 static int zone_ctor(void *, int, void *, int);
240 static void zone_dtor(void *, int, void *);
241 static int zero_init(void *, int, int);
242 static void keg_small_init(uma_keg_t keg);
243 static void keg_large_init(uma_keg_t keg);
244 static void zone_foreach(void (*zfunc)(uma_zone_t));
245 static void zone_timeout(uma_zone_t zone);
246 static int hash_alloc(struct uma_hash *);
247 static int hash_expand(struct uma_hash *, struct uma_hash *);
248 static void hash_free(struct uma_hash *hash);
249 static void uma_timeout(void *);
250 static void uma_startup3(void);
251 static void *zone_alloc_item(uma_zone_t, void *, int, int);
252 static void zone_free_item(uma_zone_t, void *, void *, enum zfreeskip);
253 static void bucket_enable(void);
254 static void bucket_init(void);
255 static uma_bucket_t bucket_alloc(uma_zone_t zone, void *, int);
256 static void bucket_free(uma_zone_t zone, uma_bucket_t, void *);
257 static void bucket_zone_drain(void);
258 static uma_bucket_t zone_alloc_bucket(uma_zone_t, void *, int, int);
259 static uma_slab_t zone_fetch_slab(uma_zone_t, uma_keg_t, int, int);
260 static uma_slab_t zone_fetch_slab_multi(uma_zone_t, uma_keg_t, int, int);
261 static void *slab_alloc_item(uma_keg_t keg, uma_slab_t slab);
262 static void slab_free_item(uma_keg_t keg, uma_slab_t slab, void *item);
263 static uma_keg_t uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit,
264     uma_fini fini, int align, uint32_t flags);
265 static int zone_import(uma_zone_t, void **, int, int, int);
266 static void zone_release(uma_zone_t, void **, int);
267 static void uma_zero_item(void *, uma_zone_t);
268 
269 void uma_print_zone(uma_zone_t);
270 void uma_print_stats(void);
271 static int sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS);
272 static int sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS);
273 
274 #ifdef INVARIANTS
275 static void uma_dbg_free(uma_zone_t zone, uma_slab_t slab, void *item);
276 static void uma_dbg_alloc(uma_zone_t zone, uma_slab_t slab, void *item);
277 #endif
278 
279 SYSINIT(uma_startup3, SI_SUB_VM_CONF, SI_ORDER_SECOND, uma_startup3, NULL);
280 
281 SYSCTL_PROC(_vm, OID_AUTO, zone_count, CTLFLAG_RD|CTLTYPE_INT,
282     0, 0, sysctl_vm_zone_count, "I", "Number of UMA zones");
283 
284 SYSCTL_PROC(_vm, OID_AUTO, zone_stats, CTLFLAG_RD|CTLTYPE_STRUCT,
285     0, 0, sysctl_vm_zone_stats, "s,struct uma_type_header", "Zone Stats");
286 
287 static int zone_warnings = 1;
288 SYSCTL_INT(_vm, OID_AUTO, zone_warnings, CTLFLAG_RWTUN, &zone_warnings, 0,
289     "Warn when UMA zones becomes full");
290 
291 /* Adjust bytes under management by UMA. */
292 static inline void
293 uma_total_dec(unsigned long size)
294 {
295 
296 	atomic_subtract_long(&uma_kmem_total, size);
297 }
298 
299 static inline void
300 uma_total_inc(unsigned long size)
301 {
302 
303 	if (atomic_fetchadd_long(&uma_kmem_total, size) > uma_kmem_limit)
304 		uma_reclaim_wakeup();
305 }
306 
307 /*
308  * This routine checks to see whether or not it's safe to enable buckets.
309  */
310 static void
311 bucket_enable(void)
312 {
313 	bucketdisable = vm_page_count_min();
314 }
315 
316 /*
317  * Initialize bucket_zones, the array of zones of buckets of various sizes.
318  *
319  * For each zone, calculate the memory required for each bucket, consisting
320  * of the header and an array of pointers.
321  */
322 static void
323 bucket_init(void)
324 {
325 	struct uma_bucket_zone *ubz;
326 	int size;
327 
328 	for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++) {
329 		size = roundup(sizeof(struct uma_bucket), sizeof(void *));
330 		size += sizeof(void *) * ubz->ubz_entries;
331 		ubz->ubz_zone = uma_zcreate(ubz->ubz_name, size,
332 		    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR,
333 		    UMA_ZONE_MTXCLASS | UMA_ZFLAG_BUCKET | UMA_ZONE_NUMA);
334 	}
335 }
336 
337 /*
338  * Given a desired number of entries for a bucket, return the zone from which
339  * to allocate the bucket.
340  */
341 static struct uma_bucket_zone *
342 bucket_zone_lookup(int entries)
343 {
344 	struct uma_bucket_zone *ubz;
345 
346 	for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++)
347 		if (ubz->ubz_entries >= entries)
348 			return (ubz);
349 	ubz--;
350 	return (ubz);
351 }
352 
353 static int
354 bucket_select(int size)
355 {
356 	struct uma_bucket_zone *ubz;
357 
358 	ubz = &bucket_zones[0];
359 	if (size > ubz->ubz_maxsize)
360 		return MAX((ubz->ubz_maxsize * ubz->ubz_entries) / size, 1);
361 
362 	for (; ubz->ubz_entries != 0; ubz++)
363 		if (ubz->ubz_maxsize < size)
364 			break;
365 	ubz--;
366 	return (ubz->ubz_entries);
367 }
368 
369 static uma_bucket_t
370 bucket_alloc(uma_zone_t zone, void *udata, int flags)
371 {
372 	struct uma_bucket_zone *ubz;
373 	uma_bucket_t bucket;
374 
375 	/*
376 	 * This is to stop us from allocating per cpu buckets while we're
377 	 * running out of vm.boot_pages.  Otherwise, we would exhaust the
378 	 * boot pages.  This also prevents us from allocating buckets in
379 	 * low memory situations.
380 	 */
381 	if (bucketdisable)
382 		return (NULL);
383 	/*
384 	 * To limit bucket recursion we store the original zone flags
385 	 * in a cookie passed via zalloc_arg/zfree_arg.  This allows the
386 	 * NOVM flag to persist even through deep recursions.  We also
387 	 * store ZFLAG_BUCKET once we have recursed attempting to allocate
388 	 * a bucket for a bucket zone so we do not allow infinite bucket
389 	 * recursion.  This cookie will even persist to frees of unused
390 	 * buckets via the allocation path or bucket allocations in the
391 	 * free path.
392 	 */
393 	if ((zone->uz_flags & UMA_ZFLAG_BUCKET) == 0)
394 		udata = (void *)(uintptr_t)zone->uz_flags;
395 	else {
396 		if ((uintptr_t)udata & UMA_ZFLAG_BUCKET)
397 			return (NULL);
398 		udata = (void *)((uintptr_t)udata | UMA_ZFLAG_BUCKET);
399 	}
400 	if ((uintptr_t)udata & UMA_ZFLAG_CACHEONLY)
401 		flags |= M_NOVM;
402 	ubz = bucket_zone_lookup(zone->uz_count);
403 	if (ubz->ubz_zone == zone && (ubz + 1)->ubz_entries != 0)
404 		ubz++;
405 	bucket = uma_zalloc_arg(ubz->ubz_zone, udata, flags);
406 	if (bucket) {
407 #ifdef INVARIANTS
408 		bzero(bucket->ub_bucket, sizeof(void *) * ubz->ubz_entries);
409 #endif
410 		bucket->ub_cnt = 0;
411 		bucket->ub_entries = ubz->ubz_entries;
412 	}
413 
414 	return (bucket);
415 }
416 
417 static void
418 bucket_free(uma_zone_t zone, uma_bucket_t bucket, void *udata)
419 {
420 	struct uma_bucket_zone *ubz;
421 
422 	KASSERT(bucket->ub_cnt == 0,
423 	    ("bucket_free: Freeing a non free bucket."));
424 	if ((zone->uz_flags & UMA_ZFLAG_BUCKET) == 0)
425 		udata = (void *)(uintptr_t)zone->uz_flags;
426 	ubz = bucket_zone_lookup(bucket->ub_entries);
427 	uma_zfree_arg(ubz->ubz_zone, bucket, udata);
428 }
429 
430 static void
431 bucket_zone_drain(void)
432 {
433 	struct uma_bucket_zone *ubz;
434 
435 	for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++)
436 		zone_drain(ubz->ubz_zone);
437 }
438 
439 static void
440 zone_log_warning(uma_zone_t zone)
441 {
442 	static const struct timeval warninterval = { 300, 0 };
443 
444 	if (!zone_warnings || zone->uz_warning == NULL)
445 		return;
446 
447 	if (ratecheck(&zone->uz_ratecheck, &warninterval))
448 		printf("[zone: %s] %s\n", zone->uz_name, zone->uz_warning);
449 }
450 
451 static inline void
452 zone_maxaction(uma_zone_t zone)
453 {
454 
455 	if (zone->uz_maxaction.ta_func != NULL)
456 		taskqueue_enqueue(taskqueue_thread, &zone->uz_maxaction);
457 }
458 
459 static void
460 zone_foreach_keg(uma_zone_t zone, void (*kegfn)(uma_keg_t))
461 {
462 	uma_klink_t klink;
463 
464 	LIST_FOREACH(klink, &zone->uz_kegs, kl_link)
465 		kegfn(klink->kl_keg);
466 }
467 
468 /*
469  * Routine called by timeout which is used to fire off some time interval
470  * based calculations.  (stats, hash size, etc.)
471  *
472  * Arguments:
473  *	arg   Unused
474  *
475  * Returns:
476  *	Nothing
477  */
478 static void
479 uma_timeout(void *unused)
480 {
481 	bucket_enable();
482 	zone_foreach(zone_timeout);
483 
484 	/* Reschedule this event */
485 	callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL);
486 }
487 
488 /*
489  * Routine to perform timeout driven calculations.  This expands the
490  * hashes and does per cpu statistics aggregation.
491  *
492  *  Returns nothing.
493  */
494 static void
495 keg_timeout(uma_keg_t keg)
496 {
497 
498 	KEG_LOCK(keg);
499 	/*
500 	 * Expand the keg hash table.
501 	 *
502 	 * This is done if the number of slabs is larger than the hash size.
503 	 * What I'm trying to do here is completely reduce collisions.  This
504 	 * may be a little aggressive.  Should I allow for two collisions max?
505 	 */
506 	if (keg->uk_flags & UMA_ZONE_HASH &&
507 	    keg->uk_pages / keg->uk_ppera >= keg->uk_hash.uh_hashsize) {
508 		struct uma_hash newhash;
509 		struct uma_hash oldhash;
510 		int ret;
511 
512 		/*
513 		 * This is so involved because allocating and freeing
514 		 * while the keg lock is held will lead to deadlock.
515 		 * I have to do everything in stages and check for
516 		 * races.
517 		 */
518 		newhash = keg->uk_hash;
519 		KEG_UNLOCK(keg);
520 		ret = hash_alloc(&newhash);
521 		KEG_LOCK(keg);
522 		if (ret) {
523 			if (hash_expand(&keg->uk_hash, &newhash)) {
524 				oldhash = keg->uk_hash;
525 				keg->uk_hash = newhash;
526 			} else
527 				oldhash = newhash;
528 
529 			KEG_UNLOCK(keg);
530 			hash_free(&oldhash);
531 			return;
532 		}
533 	}
534 	KEG_UNLOCK(keg);
535 }
536 
537 static void
538 zone_timeout(uma_zone_t zone)
539 {
540 
541 	zone_foreach_keg(zone, &keg_timeout);
542 }
543 
544 /*
545  * Allocate and zero fill the next sized hash table from the appropriate
546  * backing store.
547  *
548  * Arguments:
549  *	hash  A new hash structure with the old hash size in uh_hashsize
550  *
551  * Returns:
552  *	1 on success and 0 on failure.
553  */
554 static int
555 hash_alloc(struct uma_hash *hash)
556 {
557 	int oldsize;
558 	int alloc;
559 
560 	oldsize = hash->uh_hashsize;
561 
562 	/* We're just going to go to a power of two greater */
563 	if (oldsize)  {
564 		hash->uh_hashsize = oldsize * 2;
565 		alloc = sizeof(hash->uh_slab_hash[0]) * hash->uh_hashsize;
566 		hash->uh_slab_hash = (struct slabhead *)malloc(alloc,
567 		    M_UMAHASH, M_NOWAIT);
568 	} else {
569 		alloc = sizeof(hash->uh_slab_hash[0]) * UMA_HASH_SIZE_INIT;
570 		hash->uh_slab_hash = zone_alloc_item(hashzone, NULL,
571 		    UMA_ANYDOMAIN, M_WAITOK);
572 		hash->uh_hashsize = UMA_HASH_SIZE_INIT;
573 	}
574 	if (hash->uh_slab_hash) {
575 		bzero(hash->uh_slab_hash, alloc);
576 		hash->uh_hashmask = hash->uh_hashsize - 1;
577 		return (1);
578 	}
579 
580 	return (0);
581 }
582 
583 /*
584  * Expands the hash table for HASH zones.  This is done from zone_timeout
585  * to reduce collisions.  This must not be done in the regular allocation
586  * path, otherwise, we can recurse on the vm while allocating pages.
587  *
588  * Arguments:
589  *	oldhash  The hash you want to expand
590  *	newhash  The hash structure for the new table
591  *
592  * Returns:
593  *	Nothing
594  *
595  * Discussion:
596  */
597 static int
598 hash_expand(struct uma_hash *oldhash, struct uma_hash *newhash)
599 {
600 	uma_slab_t slab;
601 	int hval;
602 	int i;
603 
604 	if (!newhash->uh_slab_hash)
605 		return (0);
606 
607 	if (oldhash->uh_hashsize >= newhash->uh_hashsize)
608 		return (0);
609 
610 	/*
611 	 * I need to investigate hash algorithms for resizing without a
612 	 * full rehash.
613 	 */
614 
615 	for (i = 0; i < oldhash->uh_hashsize; i++)
616 		while (!SLIST_EMPTY(&oldhash->uh_slab_hash[i])) {
617 			slab = SLIST_FIRST(&oldhash->uh_slab_hash[i]);
618 			SLIST_REMOVE_HEAD(&oldhash->uh_slab_hash[i], us_hlink);
619 			hval = UMA_HASH(newhash, slab->us_data);
620 			SLIST_INSERT_HEAD(&newhash->uh_slab_hash[hval],
621 			    slab, us_hlink);
622 		}
623 
624 	return (1);
625 }
626 
627 /*
628  * Free the hash bucket to the appropriate backing store.
629  *
630  * Arguments:
631  *	slab_hash  The hash bucket we're freeing
632  *	hashsize   The number of entries in that hash bucket
633  *
634  * Returns:
635  *	Nothing
636  */
637 static void
638 hash_free(struct uma_hash *hash)
639 {
640 	if (hash->uh_slab_hash == NULL)
641 		return;
642 	if (hash->uh_hashsize == UMA_HASH_SIZE_INIT)
643 		zone_free_item(hashzone, hash->uh_slab_hash, NULL, SKIP_NONE);
644 	else
645 		free(hash->uh_slab_hash, M_UMAHASH);
646 }
647 
648 /*
649  * Frees all outstanding items in a bucket
650  *
651  * Arguments:
652  *	zone   The zone to free to, must be unlocked.
653  *	bucket The free/alloc bucket with items, cpu queue must be locked.
654  *
655  * Returns:
656  *	Nothing
657  */
658 
659 static void
660 bucket_drain(uma_zone_t zone, uma_bucket_t bucket)
661 {
662 	int i;
663 
664 	if (bucket == NULL)
665 		return;
666 
667 	if (zone->uz_fini)
668 		for (i = 0; i < bucket->ub_cnt; i++)
669 			zone->uz_fini(bucket->ub_bucket[i], zone->uz_size);
670 	zone->uz_release(zone->uz_arg, bucket->ub_bucket, bucket->ub_cnt);
671 	bucket->ub_cnt = 0;
672 }
673 
674 /*
675  * Drains the per cpu caches for a zone.
676  *
677  * NOTE: This may only be called while the zone is being turn down, and not
678  * during normal operation.  This is necessary in order that we do not have
679  * to migrate CPUs to drain the per-CPU caches.
680  *
681  * Arguments:
682  *	zone     The zone to drain, must be unlocked.
683  *
684  * Returns:
685  *	Nothing
686  */
687 static void
688 cache_drain(uma_zone_t zone)
689 {
690 	uma_cache_t cache;
691 	int cpu;
692 
693 	/*
694 	 * XXX: It is safe to not lock the per-CPU caches, because we're
695 	 * tearing down the zone anyway.  I.e., there will be no further use
696 	 * of the caches at this point.
697 	 *
698 	 * XXX: It would good to be able to assert that the zone is being
699 	 * torn down to prevent improper use of cache_drain().
700 	 *
701 	 * XXX: We lock the zone before passing into bucket_cache_drain() as
702 	 * it is used elsewhere.  Should the tear-down path be made special
703 	 * there in some form?
704 	 */
705 	CPU_FOREACH(cpu) {
706 		cache = &zone->uz_cpu[cpu];
707 		bucket_drain(zone, cache->uc_allocbucket);
708 		bucket_drain(zone, cache->uc_freebucket);
709 		if (cache->uc_allocbucket != NULL)
710 			bucket_free(zone, cache->uc_allocbucket, NULL);
711 		if (cache->uc_freebucket != NULL)
712 			bucket_free(zone, cache->uc_freebucket, NULL);
713 		cache->uc_allocbucket = cache->uc_freebucket = NULL;
714 	}
715 	ZONE_LOCK(zone);
716 	bucket_cache_drain(zone);
717 	ZONE_UNLOCK(zone);
718 }
719 
720 static void
721 cache_shrink(uma_zone_t zone)
722 {
723 
724 	if (zone->uz_flags & UMA_ZFLAG_INTERNAL)
725 		return;
726 
727 	ZONE_LOCK(zone);
728 	zone->uz_count = (zone->uz_count_min + zone->uz_count) / 2;
729 	ZONE_UNLOCK(zone);
730 }
731 
732 static void
733 cache_drain_safe_cpu(uma_zone_t zone)
734 {
735 	uma_cache_t cache;
736 	uma_bucket_t b1, b2;
737 	int domain;
738 
739 	if (zone->uz_flags & UMA_ZFLAG_INTERNAL)
740 		return;
741 
742 	b1 = b2 = NULL;
743 	ZONE_LOCK(zone);
744 	critical_enter();
745 	if (zone->uz_flags & UMA_ZONE_NUMA)
746 		domain = PCPU_GET(domain);
747 	else
748 		domain = 0;
749 	cache = &zone->uz_cpu[curcpu];
750 	if (cache->uc_allocbucket) {
751 		if (cache->uc_allocbucket->ub_cnt != 0)
752 			LIST_INSERT_HEAD(&zone->uz_domain[domain].uzd_buckets,
753 			    cache->uc_allocbucket, ub_link);
754 		else
755 			b1 = cache->uc_allocbucket;
756 		cache->uc_allocbucket = NULL;
757 	}
758 	if (cache->uc_freebucket) {
759 		if (cache->uc_freebucket->ub_cnt != 0)
760 			LIST_INSERT_HEAD(&zone->uz_domain[domain].uzd_buckets,
761 			    cache->uc_freebucket, ub_link);
762 		else
763 			b2 = cache->uc_freebucket;
764 		cache->uc_freebucket = NULL;
765 	}
766 	critical_exit();
767 	ZONE_UNLOCK(zone);
768 	if (b1)
769 		bucket_free(zone, b1, NULL);
770 	if (b2)
771 		bucket_free(zone, b2, NULL);
772 }
773 
774 /*
775  * Safely drain per-CPU caches of a zone(s) to alloc bucket.
776  * This is an expensive call because it needs to bind to all CPUs
777  * one by one and enter a critical section on each of them in order
778  * to safely access their cache buckets.
779  * Zone lock must not be held on call this function.
780  */
781 static void
782 cache_drain_safe(uma_zone_t zone)
783 {
784 	int cpu;
785 
786 	/*
787 	 * Polite bucket sizes shrinking was not enouth, shrink aggressively.
788 	 */
789 	if (zone)
790 		cache_shrink(zone);
791 	else
792 		zone_foreach(cache_shrink);
793 
794 	CPU_FOREACH(cpu) {
795 		thread_lock(curthread);
796 		sched_bind(curthread, cpu);
797 		thread_unlock(curthread);
798 
799 		if (zone)
800 			cache_drain_safe_cpu(zone);
801 		else
802 			zone_foreach(cache_drain_safe_cpu);
803 	}
804 	thread_lock(curthread);
805 	sched_unbind(curthread);
806 	thread_unlock(curthread);
807 }
808 
809 /*
810  * Drain the cached buckets from a zone.  Expects a locked zone on entry.
811  */
812 static void
813 bucket_cache_drain(uma_zone_t zone)
814 {
815 	uma_zone_domain_t zdom;
816 	uma_bucket_t bucket;
817 	int i;
818 
819 	/*
820 	 * Drain the bucket queues and free the buckets.
821 	 */
822 	for (i = 0; i < vm_ndomains; i++) {
823 		zdom = &zone->uz_domain[i];
824 		while ((bucket = LIST_FIRST(&zdom->uzd_buckets)) != NULL) {
825 			LIST_REMOVE(bucket, ub_link);
826 			ZONE_UNLOCK(zone);
827 			bucket_drain(zone, bucket);
828 			bucket_free(zone, bucket, NULL);
829 			ZONE_LOCK(zone);
830 		}
831 	}
832 
833 	/*
834 	 * Shrink further bucket sizes.  Price of single zone lock collision
835 	 * is probably lower then price of global cache drain.
836 	 */
837 	if (zone->uz_count > zone->uz_count_min)
838 		zone->uz_count--;
839 }
840 
841 static void
842 keg_free_slab(uma_keg_t keg, uma_slab_t slab, int start)
843 {
844 	uint8_t *mem;
845 	int i;
846 	uint8_t flags;
847 
848 	CTR4(KTR_UMA, "keg_free_slab keg %s(%p) slab %p, returning %d bytes",
849 	    keg->uk_name, keg, slab, PAGE_SIZE * keg->uk_ppera);
850 
851 	mem = slab->us_data;
852 	flags = slab->us_flags;
853 	i = start;
854 	if (keg->uk_fini != NULL) {
855 		for (i--; i > -1; i--)
856 			keg->uk_fini(slab->us_data + (keg->uk_rsize * i),
857 			    keg->uk_size);
858 	}
859 	if (keg->uk_flags & UMA_ZONE_OFFPAGE)
860 		zone_free_item(keg->uk_slabzone, slab, NULL, SKIP_NONE);
861 	keg->uk_freef(mem, PAGE_SIZE * keg->uk_ppera, flags);
862 	uma_total_dec(PAGE_SIZE * keg->uk_ppera);
863 }
864 
865 /*
866  * Frees pages from a keg back to the system.  This is done on demand from
867  * the pageout daemon.
868  *
869  * Returns nothing.
870  */
871 static void
872 keg_drain(uma_keg_t keg)
873 {
874 	struct slabhead freeslabs = { 0 };
875 	uma_domain_t dom;
876 	uma_slab_t slab, tmp;
877 	int i;
878 
879 	/*
880 	 * We don't want to take pages from statically allocated kegs at this
881 	 * time
882 	 */
883 	if (keg->uk_flags & UMA_ZONE_NOFREE || keg->uk_freef == NULL)
884 		return;
885 
886 	CTR3(KTR_UMA, "keg_drain %s(%p) free items: %u",
887 	    keg->uk_name, keg, keg->uk_free);
888 	KEG_LOCK(keg);
889 	if (keg->uk_free == 0)
890 		goto finished;
891 
892 	for (i = 0; i < vm_ndomains; i++) {
893 		dom = &keg->uk_domain[i];
894 		LIST_FOREACH_SAFE(slab, &dom->ud_free_slab, us_link, tmp) {
895 			/* We have nowhere to free these to. */
896 			if (slab->us_flags & UMA_SLAB_BOOT)
897 				continue;
898 
899 			LIST_REMOVE(slab, us_link);
900 			keg->uk_pages -= keg->uk_ppera;
901 			keg->uk_free -= keg->uk_ipers;
902 
903 			if (keg->uk_flags & UMA_ZONE_HASH)
904 				UMA_HASH_REMOVE(&keg->uk_hash, slab,
905 				    slab->us_data);
906 
907 			SLIST_INSERT_HEAD(&freeslabs, slab, us_hlink);
908 		}
909 	}
910 
911 finished:
912 	KEG_UNLOCK(keg);
913 
914 	while ((slab = SLIST_FIRST(&freeslabs)) != NULL) {
915 		SLIST_REMOVE(&freeslabs, slab, uma_slab, us_hlink);
916 		keg_free_slab(keg, slab, keg->uk_ipers);
917 	}
918 }
919 
920 static void
921 zone_drain_wait(uma_zone_t zone, int waitok)
922 {
923 
924 	/*
925 	 * Set draining to interlock with zone_dtor() so we can release our
926 	 * locks as we go.  Only dtor() should do a WAITOK call since it
927 	 * is the only call that knows the structure will still be available
928 	 * when it wakes up.
929 	 */
930 	ZONE_LOCK(zone);
931 	while (zone->uz_flags & UMA_ZFLAG_DRAINING) {
932 		if (waitok == M_NOWAIT)
933 			goto out;
934 		msleep(zone, zone->uz_lockptr, PVM, "zonedrain", 1);
935 	}
936 	zone->uz_flags |= UMA_ZFLAG_DRAINING;
937 	bucket_cache_drain(zone);
938 	ZONE_UNLOCK(zone);
939 	/*
940 	 * The DRAINING flag protects us from being freed while
941 	 * we're running.  Normally the uma_rwlock would protect us but we
942 	 * must be able to release and acquire the right lock for each keg.
943 	 */
944 	zone_foreach_keg(zone, &keg_drain);
945 	ZONE_LOCK(zone);
946 	zone->uz_flags &= ~UMA_ZFLAG_DRAINING;
947 	wakeup(zone);
948 out:
949 	ZONE_UNLOCK(zone);
950 }
951 
952 void
953 zone_drain(uma_zone_t zone)
954 {
955 
956 	zone_drain_wait(zone, M_NOWAIT);
957 }
958 
959 /*
960  * Allocate a new slab for a keg.  This does not insert the slab onto a list.
961  *
962  * Arguments:
963  *	wait  Shall we wait?
964  *
965  * Returns:
966  *	The slab that was allocated or NULL if there is no memory and the
967  *	caller specified M_NOWAIT.
968  */
969 static uma_slab_t
970 keg_alloc_slab(uma_keg_t keg, uma_zone_t zone, int domain, int wait)
971 {
972 	uma_alloc allocf;
973 	uma_slab_t slab;
974 	unsigned long size;
975 	uint8_t *mem;
976 	uint8_t flags;
977 	int i;
978 
979 	KASSERT(domain >= 0 && domain < vm_ndomains,
980 	    ("keg_alloc_slab: domain %d out of range", domain));
981 	mtx_assert(&keg->uk_lock, MA_OWNED);
982 	slab = NULL;
983 	mem = NULL;
984 
985 	allocf = keg->uk_allocf;
986 	KEG_UNLOCK(keg);
987 	size = keg->uk_ppera * PAGE_SIZE;
988 
989 	if (keg->uk_flags & UMA_ZONE_OFFPAGE) {
990 		slab = zone_alloc_item(keg->uk_slabzone, NULL, domain, wait);
991 		if (slab == NULL)
992 			goto out;
993 	}
994 
995 	/*
996 	 * This reproduces the old vm_zone behavior of zero filling pages the
997 	 * first time they are added to a zone.
998 	 *
999 	 * Malloced items are zeroed in uma_zalloc.
1000 	 */
1001 
1002 	if ((keg->uk_flags & UMA_ZONE_MALLOC) == 0)
1003 		wait |= M_ZERO;
1004 	else
1005 		wait &= ~M_ZERO;
1006 
1007 	if (keg->uk_flags & UMA_ZONE_NODUMP)
1008 		wait |= M_NODUMP;
1009 
1010 	/* zone is passed for legacy reasons. */
1011 	mem = allocf(zone, size, domain, &flags, wait);
1012 	if (mem == NULL) {
1013 		if (keg->uk_flags & UMA_ZONE_OFFPAGE)
1014 			zone_free_item(keg->uk_slabzone, slab, NULL, SKIP_NONE);
1015 		slab = NULL;
1016 		goto out;
1017 	}
1018 	uma_total_inc(size);
1019 
1020 	/* Point the slab into the allocated memory */
1021 	if (!(keg->uk_flags & UMA_ZONE_OFFPAGE))
1022 		slab = (uma_slab_t )(mem + keg->uk_pgoff);
1023 
1024 	if (keg->uk_flags & UMA_ZONE_VTOSLAB)
1025 		for (i = 0; i < keg->uk_ppera; i++)
1026 			vsetslab((vm_offset_t)mem + (i * PAGE_SIZE), slab);
1027 
1028 	slab->us_keg = keg;
1029 	slab->us_data = mem;
1030 	slab->us_freecount = keg->uk_ipers;
1031 	slab->us_flags = flags;
1032 	slab->us_domain = domain;
1033 	BIT_FILL(SLAB_SETSIZE, &slab->us_free);
1034 #ifdef INVARIANTS
1035 	BIT_ZERO(SLAB_SETSIZE, &slab->us_debugfree);
1036 #endif
1037 
1038 	if (keg->uk_init != NULL) {
1039 		for (i = 0; i < keg->uk_ipers; i++)
1040 			if (keg->uk_init(slab->us_data + (keg->uk_rsize * i),
1041 			    keg->uk_size, wait) != 0)
1042 				break;
1043 		if (i != keg->uk_ipers) {
1044 			keg_free_slab(keg, slab, i);
1045 			slab = NULL;
1046 			goto out;
1047 		}
1048 	}
1049 out:
1050 	KEG_LOCK(keg);
1051 
1052 	CTR3(KTR_UMA, "keg_alloc_slab: allocated slab %p for %s(%p)",
1053 	    slab, keg->uk_name, keg);
1054 
1055 	if (slab != NULL) {
1056 		if (keg->uk_flags & UMA_ZONE_HASH)
1057 			UMA_HASH_INSERT(&keg->uk_hash, slab, mem);
1058 
1059 		keg->uk_pages += keg->uk_ppera;
1060 		keg->uk_free += keg->uk_ipers;
1061 	}
1062 
1063 	return (slab);
1064 }
1065 
1066 /*
1067  * This function is intended to be used early on in place of page_alloc() so
1068  * that we may use the boot time page cache to satisfy allocations before
1069  * the VM is ready.
1070  */
1071 static void *
1072 startup_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
1073     int wait)
1074 {
1075 	uma_keg_t keg;
1076 	void *mem;
1077 	int pages;
1078 
1079 	keg = zone_first_keg(zone);
1080 	pages = howmany(bytes, PAGE_SIZE);
1081 	KASSERT(pages > 0, ("startup_alloc can't reserve 0 pages\n"));
1082 
1083 	/*
1084 	 * Check our small startup cache to see if it has pages remaining.
1085 	 */
1086 	mtx_lock(&uma_boot_pages_mtx);
1087 	if (pages <= boot_pages) {
1088 		mem = bootmem;
1089 		boot_pages -= pages;
1090 		bootmem += pages * PAGE_SIZE;
1091 		mtx_unlock(&uma_boot_pages_mtx);
1092 		*pflag = UMA_SLAB_BOOT;
1093 		return (mem);
1094 	}
1095 	mtx_unlock(&uma_boot_pages_mtx);
1096 	if (booted < UMA_STARTUP2)
1097 		panic("UMA: Increase vm.boot_pages");
1098 	/*
1099 	 * Now that we've booted reset these users to their real allocator.
1100 	 */
1101 #ifdef UMA_MD_SMALL_ALLOC
1102 	keg->uk_allocf = (keg->uk_ppera > 1) ? page_alloc : uma_small_alloc;
1103 #else
1104 	keg->uk_allocf = page_alloc;
1105 #endif
1106 	return keg->uk_allocf(zone, bytes, domain, pflag, wait);
1107 }
1108 
1109 /*
1110  * Allocates a number of pages from the system
1111  *
1112  * Arguments:
1113  *	bytes  The number of bytes requested
1114  *	wait  Shall we wait?
1115  *
1116  * Returns:
1117  *	A pointer to the alloced memory or possibly
1118  *	NULL if M_NOWAIT is set.
1119  */
1120 static void *
1121 page_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
1122     int wait)
1123 {
1124 	void *p;	/* Returned page */
1125 
1126 	*pflag = UMA_SLAB_KERNEL;
1127 	p = (void *) kmem_malloc_domain(domain, bytes, wait);
1128 
1129 	return (p);
1130 }
1131 
1132 /*
1133  * Allocates a number of pages from within an object
1134  *
1135  * Arguments:
1136  *	bytes  The number of bytes requested
1137  *	wait   Shall we wait?
1138  *
1139  * Returns:
1140  *	A pointer to the alloced memory or possibly
1141  *	NULL if M_NOWAIT is set.
1142  */
1143 static void *
1144 noobj_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *flags,
1145     int wait)
1146 {
1147 	TAILQ_HEAD(, vm_page) alloctail;
1148 	u_long npages;
1149 	vm_offset_t retkva, zkva;
1150 	vm_page_t p, p_next;
1151 	uma_keg_t keg;
1152 
1153 	TAILQ_INIT(&alloctail);
1154 	keg = zone_first_keg(zone);
1155 
1156 	npages = howmany(bytes, PAGE_SIZE);
1157 	while (npages > 0) {
1158 		p = vm_page_alloc_domain(NULL, 0, domain, VM_ALLOC_INTERRUPT |
1159 		    VM_ALLOC_WIRED | VM_ALLOC_NOOBJ |
1160 		    ((wait & M_WAITOK) != 0 ? VM_ALLOC_WAITOK :
1161 		    VM_ALLOC_NOWAIT));
1162 		if (p != NULL) {
1163 			/*
1164 			 * Since the page does not belong to an object, its
1165 			 * listq is unused.
1166 			 */
1167 			TAILQ_INSERT_TAIL(&alloctail, p, listq);
1168 			npages--;
1169 			continue;
1170 		}
1171 		/*
1172 		 * Page allocation failed, free intermediate pages and
1173 		 * exit.
1174 		 */
1175 		TAILQ_FOREACH_SAFE(p, &alloctail, listq, p_next) {
1176 			vm_page_unwire(p, PQ_NONE);
1177 			vm_page_free(p);
1178 		}
1179 		return (NULL);
1180 	}
1181 	*flags = UMA_SLAB_PRIV;
1182 	zkva = keg->uk_kva +
1183 	    atomic_fetchadd_long(&keg->uk_offset, round_page(bytes));
1184 	retkva = zkva;
1185 	TAILQ_FOREACH(p, &alloctail, listq) {
1186 		pmap_qenter(zkva, &p, 1);
1187 		zkva += PAGE_SIZE;
1188 	}
1189 
1190 	return ((void *)retkva);
1191 }
1192 
1193 /*
1194  * Frees a number of pages to the system
1195  *
1196  * Arguments:
1197  *	mem   A pointer to the memory to be freed
1198  *	size  The size of the memory being freed
1199  *	flags The original p->us_flags field
1200  *
1201  * Returns:
1202  *	Nothing
1203  */
1204 static void
1205 page_free(void *mem, vm_size_t size, uint8_t flags)
1206 {
1207 	struct vmem *vmem;
1208 
1209 	if (flags & UMA_SLAB_KERNEL)
1210 		vmem = kernel_arena;
1211 	else
1212 		panic("UMA: page_free used with invalid flags %x", flags);
1213 
1214 	kmem_free(vmem, (vm_offset_t)mem, size);
1215 }
1216 
1217 /*
1218  * Zero fill initializer
1219  *
1220  * Arguments/Returns follow uma_init specifications
1221  */
1222 static int
1223 zero_init(void *mem, int size, int flags)
1224 {
1225 	bzero(mem, size);
1226 	return (0);
1227 }
1228 
1229 /*
1230  * Finish creating a small uma keg.  This calculates ipers, and the keg size.
1231  *
1232  * Arguments
1233  *	keg  The zone we should initialize
1234  *
1235  * Returns
1236  *	Nothing
1237  */
1238 static void
1239 keg_small_init(uma_keg_t keg)
1240 {
1241 	u_int rsize;
1242 	u_int memused;
1243 	u_int wastedspace;
1244 	u_int shsize;
1245 	u_int slabsize;
1246 
1247 	if (keg->uk_flags & UMA_ZONE_PCPU) {
1248 		u_int ncpus = (mp_maxid + 1) ? (mp_maxid + 1) : MAXCPU;
1249 
1250 		slabsize = sizeof(struct pcpu);
1251 		keg->uk_ppera = howmany(ncpus * sizeof(struct pcpu),
1252 		    PAGE_SIZE);
1253 	} else {
1254 		slabsize = UMA_SLAB_SIZE;
1255 		keg->uk_ppera = 1;
1256 	}
1257 
1258 	/*
1259 	 * Calculate the size of each allocation (rsize) according to
1260 	 * alignment.  If the requested size is smaller than we have
1261 	 * allocation bits for we round it up.
1262 	 */
1263 	rsize = keg->uk_size;
1264 	if (rsize < slabsize / SLAB_SETSIZE)
1265 		rsize = slabsize / SLAB_SETSIZE;
1266 	if (rsize & keg->uk_align)
1267 		rsize = (rsize & ~keg->uk_align) + (keg->uk_align + 1);
1268 	keg->uk_rsize = rsize;
1269 
1270 	KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0 ||
1271 	    keg->uk_rsize < sizeof(struct pcpu),
1272 	    ("%s: size %u too large", __func__, keg->uk_rsize));
1273 
1274 	if (keg->uk_flags & UMA_ZONE_OFFPAGE)
1275 		shsize = 0;
1276 	else
1277 		shsize = sizeof(struct uma_slab);
1278 
1279 	keg->uk_ipers = (slabsize - shsize) / rsize;
1280 	KASSERT(keg->uk_ipers > 0 && keg->uk_ipers <= SLAB_SETSIZE,
1281 	    ("%s: keg->uk_ipers %u", __func__, keg->uk_ipers));
1282 
1283 	memused = keg->uk_ipers * rsize + shsize;
1284 	wastedspace = slabsize - memused;
1285 
1286 	/*
1287 	 * We can't do OFFPAGE if we're internal or if we've been
1288 	 * asked to not go to the VM for buckets.  If we do this we
1289 	 * may end up going to the VM  for slabs which we do not
1290 	 * want to do if we're UMA_ZFLAG_CACHEONLY as a result
1291 	 * of UMA_ZONE_VM, which clearly forbids it.
1292 	 */
1293 	if ((keg->uk_flags & UMA_ZFLAG_INTERNAL) ||
1294 	    (keg->uk_flags & UMA_ZFLAG_CACHEONLY))
1295 		return;
1296 
1297 	/*
1298 	 * See if using an OFFPAGE slab will limit our waste.  Only do
1299 	 * this if it permits more items per-slab.
1300 	 *
1301 	 * XXX We could try growing slabsize to limit max waste as well.
1302 	 * Historically this was not done because the VM could not
1303 	 * efficiently handle contiguous allocations.
1304 	 */
1305 	if ((wastedspace >= slabsize / UMA_MAX_WASTE) &&
1306 	    (keg->uk_ipers < (slabsize / keg->uk_rsize))) {
1307 		keg->uk_ipers = slabsize / keg->uk_rsize;
1308 		KASSERT(keg->uk_ipers > 0 && keg->uk_ipers <= SLAB_SETSIZE,
1309 		    ("%s: keg->uk_ipers %u", __func__, keg->uk_ipers));
1310 		CTR6(KTR_UMA, "UMA decided we need offpage slab headers for "
1311 		    "keg: %s(%p), calculated wastedspace = %d, "
1312 		    "maximum wasted space allowed = %d, "
1313 		    "calculated ipers = %d, "
1314 		    "new wasted space = %d\n", keg->uk_name, keg, wastedspace,
1315 		    slabsize / UMA_MAX_WASTE, keg->uk_ipers,
1316 		    slabsize - keg->uk_ipers * keg->uk_rsize);
1317 		keg->uk_flags |= UMA_ZONE_OFFPAGE;
1318 	}
1319 
1320 	if ((keg->uk_flags & UMA_ZONE_OFFPAGE) &&
1321 	    (keg->uk_flags & UMA_ZONE_VTOSLAB) == 0)
1322 		keg->uk_flags |= UMA_ZONE_HASH;
1323 }
1324 
1325 /*
1326  * Finish creating a large (> UMA_SLAB_SIZE) uma kegs.  Just give in and do
1327  * OFFPAGE for now.  When I can allow for more dynamic slab sizes this will be
1328  * more complicated.
1329  *
1330  * Arguments
1331  *	keg  The keg we should initialize
1332  *
1333  * Returns
1334  *	Nothing
1335  */
1336 static void
1337 keg_large_init(uma_keg_t keg)
1338 {
1339 	u_int shsize;
1340 
1341 	KASSERT(keg != NULL, ("Keg is null in keg_large_init"));
1342 	KASSERT((keg->uk_flags & UMA_ZFLAG_CACHEONLY) == 0,
1343 	    ("keg_large_init: Cannot large-init a UMA_ZFLAG_CACHEONLY keg"));
1344 	KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0,
1345 	    ("%s: Cannot large-init a UMA_ZONE_PCPU keg", __func__));
1346 
1347 	keg->uk_ppera = howmany(keg->uk_size, PAGE_SIZE);
1348 	keg->uk_ipers = 1;
1349 	keg->uk_rsize = keg->uk_size;
1350 
1351 	/* Check whether we have enough space to not do OFFPAGE. */
1352 	if ((keg->uk_flags & UMA_ZONE_OFFPAGE) == 0) {
1353 		shsize = sizeof(struct uma_slab);
1354 		if (shsize & UMA_ALIGN_PTR)
1355 			shsize = (shsize & ~UMA_ALIGN_PTR) +
1356 			    (UMA_ALIGN_PTR + 1);
1357 
1358 		if (PAGE_SIZE * keg->uk_ppera - keg->uk_rsize < shsize) {
1359 			/*
1360 			 * We can't do OFFPAGE if we're internal, in which case
1361 			 * we need an extra page per allocation to contain the
1362 			 * slab header.
1363 			 */
1364 			if ((keg->uk_flags & UMA_ZFLAG_INTERNAL) == 0)
1365 				keg->uk_flags |= UMA_ZONE_OFFPAGE;
1366 			else
1367 				keg->uk_ppera++;
1368 		}
1369 	}
1370 
1371 	if ((keg->uk_flags & UMA_ZONE_OFFPAGE) &&
1372 	    (keg->uk_flags & UMA_ZONE_VTOSLAB) == 0)
1373 		keg->uk_flags |= UMA_ZONE_HASH;
1374 }
1375 
1376 static void
1377 keg_cachespread_init(uma_keg_t keg)
1378 {
1379 	int alignsize;
1380 	int trailer;
1381 	int pages;
1382 	int rsize;
1383 
1384 	KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0,
1385 	    ("%s: Cannot cachespread-init a UMA_ZONE_PCPU keg", __func__));
1386 
1387 	alignsize = keg->uk_align + 1;
1388 	rsize = keg->uk_size;
1389 	/*
1390 	 * We want one item to start on every align boundary in a page.  To
1391 	 * do this we will span pages.  We will also extend the item by the
1392 	 * size of align if it is an even multiple of align.  Otherwise, it
1393 	 * would fall on the same boundary every time.
1394 	 */
1395 	if (rsize & keg->uk_align)
1396 		rsize = (rsize & ~keg->uk_align) + alignsize;
1397 	if ((rsize & alignsize) == 0)
1398 		rsize += alignsize;
1399 	trailer = rsize - keg->uk_size;
1400 	pages = (rsize * (PAGE_SIZE / alignsize)) / PAGE_SIZE;
1401 	pages = MIN(pages, (128 * 1024) / PAGE_SIZE);
1402 	keg->uk_rsize = rsize;
1403 	keg->uk_ppera = pages;
1404 	keg->uk_ipers = ((pages * PAGE_SIZE) + trailer) / rsize;
1405 	keg->uk_flags |= UMA_ZONE_OFFPAGE | UMA_ZONE_VTOSLAB;
1406 	KASSERT(keg->uk_ipers <= SLAB_SETSIZE,
1407 	    ("%s: keg->uk_ipers too high(%d) increase max_ipers", __func__,
1408 	    keg->uk_ipers));
1409 }
1410 
1411 /*
1412  * Keg header ctor.  This initializes all fields, locks, etc.  And inserts
1413  * the keg onto the global keg list.
1414  *
1415  * Arguments/Returns follow uma_ctor specifications
1416  *	udata  Actually uma_kctor_args
1417  */
1418 static int
1419 keg_ctor(void *mem, int size, void *udata, int flags)
1420 {
1421 	struct uma_kctor_args *arg = udata;
1422 	uma_keg_t keg = mem;
1423 	uma_zone_t zone;
1424 
1425 	bzero(keg, size);
1426 	keg->uk_size = arg->size;
1427 	keg->uk_init = arg->uminit;
1428 	keg->uk_fini = arg->fini;
1429 	keg->uk_align = arg->align;
1430 	keg->uk_cursor = 0;
1431 	keg->uk_free = 0;
1432 	keg->uk_reserve = 0;
1433 	keg->uk_pages = 0;
1434 	keg->uk_flags = arg->flags;
1435 	keg->uk_slabzone = NULL;
1436 
1437 	/*
1438 	 * The master zone is passed to us at keg-creation time.
1439 	 */
1440 	zone = arg->zone;
1441 	keg->uk_name = zone->uz_name;
1442 
1443 	if (arg->flags & UMA_ZONE_VM)
1444 		keg->uk_flags |= UMA_ZFLAG_CACHEONLY;
1445 
1446 	if (arg->flags & UMA_ZONE_ZINIT)
1447 		keg->uk_init = zero_init;
1448 
1449 	if (arg->flags & UMA_ZONE_MALLOC)
1450 		keg->uk_flags |= UMA_ZONE_VTOSLAB;
1451 
1452 	if (arg->flags & UMA_ZONE_PCPU)
1453 #ifdef SMP
1454 		keg->uk_flags |= UMA_ZONE_OFFPAGE;
1455 #else
1456 		keg->uk_flags &= ~UMA_ZONE_PCPU;
1457 #endif
1458 
1459 	if (keg->uk_flags & UMA_ZONE_CACHESPREAD) {
1460 		keg_cachespread_init(keg);
1461 	} else {
1462 		if (keg->uk_size > (UMA_SLAB_SIZE - sizeof(struct uma_slab)))
1463 			keg_large_init(keg);
1464 		else
1465 			keg_small_init(keg);
1466 	}
1467 
1468 	if (keg->uk_flags & UMA_ZONE_OFFPAGE)
1469 		keg->uk_slabzone = slabzone;
1470 
1471 	/*
1472 	 * If we haven't booted yet we need allocations to go through the
1473 	 * startup cache until the vm is ready.
1474 	 */
1475 	if (booted < UMA_STARTUP2)
1476 		keg->uk_allocf = startup_alloc;
1477 #ifdef UMA_MD_SMALL_ALLOC
1478 	else if (keg->uk_ppera == 1)
1479 		keg->uk_allocf = uma_small_alloc;
1480 #endif
1481 	else
1482 		keg->uk_allocf = page_alloc;
1483 #ifdef UMA_MD_SMALL_ALLOC
1484 	if (keg->uk_ppera == 1)
1485 		keg->uk_freef = uma_small_free;
1486 	else
1487 #endif
1488 		keg->uk_freef = page_free;
1489 
1490 	/*
1491 	 * Initialize keg's lock
1492 	 */
1493 	KEG_LOCK_INIT(keg, (arg->flags & UMA_ZONE_MTXCLASS));
1494 
1495 	/*
1496 	 * If we're putting the slab header in the actual page we need to
1497 	 * figure out where in each page it goes.  This calculates a right
1498 	 * justified offset into the memory on an ALIGN_PTR boundary.
1499 	 */
1500 	if (!(keg->uk_flags & UMA_ZONE_OFFPAGE)) {
1501 		u_int totsize;
1502 
1503 		/* Size of the slab struct and free list */
1504 		totsize = sizeof(struct uma_slab);
1505 
1506 		if (totsize & UMA_ALIGN_PTR)
1507 			totsize = (totsize & ~UMA_ALIGN_PTR) +
1508 			    (UMA_ALIGN_PTR + 1);
1509 		keg->uk_pgoff = (PAGE_SIZE * keg->uk_ppera) - totsize;
1510 
1511 		/*
1512 		 * The only way the following is possible is if with our
1513 		 * UMA_ALIGN_PTR adjustments we are now bigger than
1514 		 * UMA_SLAB_SIZE.  I haven't checked whether this is
1515 		 * mathematically possible for all cases, so we make
1516 		 * sure here anyway.
1517 		 */
1518 		totsize = keg->uk_pgoff + sizeof(struct uma_slab);
1519 		if (totsize > PAGE_SIZE * keg->uk_ppera) {
1520 			printf("zone %s ipers %d rsize %d size %d\n",
1521 			    zone->uz_name, keg->uk_ipers, keg->uk_rsize,
1522 			    keg->uk_size);
1523 			panic("UMA slab won't fit.");
1524 		}
1525 	}
1526 
1527 	if (keg->uk_flags & UMA_ZONE_HASH)
1528 		hash_alloc(&keg->uk_hash);
1529 
1530 	CTR5(KTR_UMA, "keg_ctor %p zone %s(%p) out %d free %d\n",
1531 	    keg, zone->uz_name, zone,
1532 	    (keg->uk_pages / keg->uk_ppera) * keg->uk_ipers - keg->uk_free,
1533 	    keg->uk_free);
1534 
1535 	LIST_INSERT_HEAD(&keg->uk_zones, zone, uz_link);
1536 
1537 	rw_wlock(&uma_rwlock);
1538 	LIST_INSERT_HEAD(&uma_kegs, keg, uk_link);
1539 	rw_wunlock(&uma_rwlock);
1540 	return (0);
1541 }
1542 
1543 /*
1544  * Zone header ctor.  This initializes all fields, locks, etc.
1545  *
1546  * Arguments/Returns follow uma_ctor specifications
1547  *	udata  Actually uma_zctor_args
1548  */
1549 static int
1550 zone_ctor(void *mem, int size, void *udata, int flags)
1551 {
1552 	struct uma_zctor_args *arg = udata;
1553 	uma_zone_t zone = mem;
1554 	uma_zone_t z;
1555 	uma_keg_t keg;
1556 
1557 	bzero(zone, size);
1558 	zone->uz_name = arg->name;
1559 	zone->uz_ctor = arg->ctor;
1560 	zone->uz_dtor = arg->dtor;
1561 	zone->uz_slab = zone_fetch_slab;
1562 	zone->uz_init = NULL;
1563 	zone->uz_fini = NULL;
1564 	zone->uz_allocs = 0;
1565 	zone->uz_frees = 0;
1566 	zone->uz_fails = 0;
1567 	zone->uz_sleeps = 0;
1568 	zone->uz_count = 0;
1569 	zone->uz_count_min = 0;
1570 	zone->uz_flags = 0;
1571 	zone->uz_warning = NULL;
1572 	/* The domain structures follow the cpu structures. */
1573 	zone->uz_domain = (struct uma_zone_domain *)&zone->uz_cpu[mp_ncpus];
1574 	timevalclear(&zone->uz_ratecheck);
1575 	keg = arg->keg;
1576 
1577 	ZONE_LOCK_INIT(zone, (arg->flags & UMA_ZONE_MTXCLASS));
1578 
1579 	/*
1580 	 * This is a pure cache zone, no kegs.
1581 	 */
1582 	if (arg->import) {
1583 		if (arg->flags & UMA_ZONE_VM)
1584 			arg->flags |= UMA_ZFLAG_CACHEONLY;
1585 		zone->uz_flags = arg->flags;
1586 		zone->uz_size = arg->size;
1587 		zone->uz_import = arg->import;
1588 		zone->uz_release = arg->release;
1589 		zone->uz_arg = arg->arg;
1590 		zone->uz_lockptr = &zone->uz_lock;
1591 		rw_wlock(&uma_rwlock);
1592 		LIST_INSERT_HEAD(&uma_cachezones, zone, uz_link);
1593 		rw_wunlock(&uma_rwlock);
1594 		goto out;
1595 	}
1596 
1597 	/*
1598 	 * Use the regular zone/keg/slab allocator.
1599 	 */
1600 	zone->uz_import = (uma_import)zone_import;
1601 	zone->uz_release = (uma_release)zone_release;
1602 	zone->uz_arg = zone;
1603 
1604 	if (arg->flags & UMA_ZONE_SECONDARY) {
1605 		KASSERT(arg->keg != NULL, ("Secondary zone on zero'd keg"));
1606 		zone->uz_init = arg->uminit;
1607 		zone->uz_fini = arg->fini;
1608 		zone->uz_lockptr = &keg->uk_lock;
1609 		zone->uz_flags |= UMA_ZONE_SECONDARY;
1610 		rw_wlock(&uma_rwlock);
1611 		ZONE_LOCK(zone);
1612 		LIST_FOREACH(z, &keg->uk_zones, uz_link) {
1613 			if (LIST_NEXT(z, uz_link) == NULL) {
1614 				LIST_INSERT_AFTER(z, zone, uz_link);
1615 				break;
1616 			}
1617 		}
1618 		ZONE_UNLOCK(zone);
1619 		rw_wunlock(&uma_rwlock);
1620 	} else if (keg == NULL) {
1621 		if ((keg = uma_kcreate(zone, arg->size, arg->uminit, arg->fini,
1622 		    arg->align, arg->flags)) == NULL)
1623 			return (ENOMEM);
1624 	} else {
1625 		struct uma_kctor_args karg;
1626 		int error;
1627 
1628 		/* We should only be here from uma_startup() */
1629 		karg.size = arg->size;
1630 		karg.uminit = arg->uminit;
1631 		karg.fini = arg->fini;
1632 		karg.align = arg->align;
1633 		karg.flags = arg->flags;
1634 		karg.zone = zone;
1635 		error = keg_ctor(arg->keg, sizeof(struct uma_keg), &karg,
1636 		    flags);
1637 		if (error)
1638 			return (error);
1639 	}
1640 
1641 	/*
1642 	 * Link in the first keg.
1643 	 */
1644 	zone->uz_klink.kl_keg = keg;
1645 	LIST_INSERT_HEAD(&zone->uz_kegs, &zone->uz_klink, kl_link);
1646 	zone->uz_lockptr = &keg->uk_lock;
1647 	zone->uz_size = keg->uk_size;
1648 	zone->uz_flags |= (keg->uk_flags &
1649 	    (UMA_ZONE_INHERIT | UMA_ZFLAG_INHERIT));
1650 
1651 	/*
1652 	 * Some internal zones don't have room allocated for the per cpu
1653 	 * caches.  If we're internal, bail out here.
1654 	 */
1655 	if (keg->uk_flags & UMA_ZFLAG_INTERNAL) {
1656 		KASSERT((zone->uz_flags & UMA_ZONE_SECONDARY) == 0,
1657 		    ("Secondary zone requested UMA_ZFLAG_INTERNAL"));
1658 		return (0);
1659 	}
1660 
1661 out:
1662 	if ((arg->flags & UMA_ZONE_MAXBUCKET) == 0)
1663 		zone->uz_count = bucket_select(zone->uz_size);
1664 	else
1665 		zone->uz_count = BUCKET_MAX;
1666 	zone->uz_count_min = zone->uz_count;
1667 
1668 	return (0);
1669 }
1670 
1671 /*
1672  * Keg header dtor.  This frees all data, destroys locks, frees the hash
1673  * table and removes the keg from the global list.
1674  *
1675  * Arguments/Returns follow uma_dtor specifications
1676  *	udata  unused
1677  */
1678 static void
1679 keg_dtor(void *arg, int size, void *udata)
1680 {
1681 	uma_keg_t keg;
1682 
1683 	keg = (uma_keg_t)arg;
1684 	KEG_LOCK(keg);
1685 	if (keg->uk_free != 0) {
1686 		printf("Freed UMA keg (%s) was not empty (%d items). "
1687 		    " Lost %d pages of memory.\n",
1688 		    keg->uk_name ? keg->uk_name : "",
1689 		    keg->uk_free, keg->uk_pages);
1690 	}
1691 	KEG_UNLOCK(keg);
1692 
1693 	hash_free(&keg->uk_hash);
1694 
1695 	KEG_LOCK_FINI(keg);
1696 }
1697 
1698 /*
1699  * Zone header dtor.
1700  *
1701  * Arguments/Returns follow uma_dtor specifications
1702  *	udata  unused
1703  */
1704 static void
1705 zone_dtor(void *arg, int size, void *udata)
1706 {
1707 	uma_klink_t klink;
1708 	uma_zone_t zone;
1709 	uma_keg_t keg;
1710 
1711 	zone = (uma_zone_t)arg;
1712 	keg = zone_first_keg(zone);
1713 
1714 	if (!(zone->uz_flags & UMA_ZFLAG_INTERNAL))
1715 		cache_drain(zone);
1716 
1717 	rw_wlock(&uma_rwlock);
1718 	LIST_REMOVE(zone, uz_link);
1719 	rw_wunlock(&uma_rwlock);
1720 	/*
1721 	 * XXX there are some races here where
1722 	 * the zone can be drained but zone lock
1723 	 * released and then refilled before we
1724 	 * remove it... we dont care for now
1725 	 */
1726 	zone_drain_wait(zone, M_WAITOK);
1727 	/*
1728 	 * Unlink all of our kegs.
1729 	 */
1730 	while ((klink = LIST_FIRST(&zone->uz_kegs)) != NULL) {
1731 		klink->kl_keg = NULL;
1732 		LIST_REMOVE(klink, kl_link);
1733 		if (klink == &zone->uz_klink)
1734 			continue;
1735 		free(klink, M_TEMP);
1736 	}
1737 	/*
1738 	 * We only destroy kegs from non secondary zones.
1739 	 */
1740 	if (keg != NULL && (zone->uz_flags & UMA_ZONE_SECONDARY) == 0)  {
1741 		rw_wlock(&uma_rwlock);
1742 		LIST_REMOVE(keg, uk_link);
1743 		rw_wunlock(&uma_rwlock);
1744 		zone_free_item(kegs, keg, NULL, SKIP_NONE);
1745 	}
1746 	ZONE_LOCK_FINI(zone);
1747 }
1748 
1749 /*
1750  * Traverses every zone in the system and calls a callback
1751  *
1752  * Arguments:
1753  *	zfunc  A pointer to a function which accepts a zone
1754  *		as an argument.
1755  *
1756  * Returns:
1757  *	Nothing
1758  */
1759 static void
1760 zone_foreach(void (*zfunc)(uma_zone_t))
1761 {
1762 	uma_keg_t keg;
1763 	uma_zone_t zone;
1764 
1765 	rw_rlock(&uma_rwlock);
1766 	LIST_FOREACH(keg, &uma_kegs, uk_link) {
1767 		LIST_FOREACH(zone, &keg->uk_zones, uz_link)
1768 			zfunc(zone);
1769 	}
1770 	rw_runlock(&uma_rwlock);
1771 }
1772 
1773 /* Public functions */
1774 /* See uma.h */
1775 void
1776 uma_startup(void *mem, int npages)
1777 {
1778 	struct uma_zctor_args args;
1779 	uma_keg_t masterkeg;
1780 	uintptr_t m;
1781 	int zsize;
1782 	int ksize;
1783 
1784 	rw_init(&uma_rwlock, "UMA lock");
1785 
1786 	ksize = sizeof(struct uma_keg) +
1787 	    (sizeof(struct uma_domain) * vm_ndomains);
1788 	zsize = sizeof(struct uma_zone) +
1789 	    (sizeof(struct uma_cache) * mp_ncpus) +
1790 	    (sizeof(struct uma_zone_domain) * vm_ndomains);
1791 
1792 	/* Use bootpages memory for the zone of zones and zone of kegs. */
1793 	m = (uintptr_t)mem;
1794 	zones = (uma_zone_t)m;
1795 	m += roundup(zsize, CACHE_LINE_SIZE);
1796 	kegs = (uma_zone_t)m;
1797 	m += roundup(zsize, CACHE_LINE_SIZE);
1798 	masterkeg = (uma_keg_t)m;
1799 	m += roundup(ksize, CACHE_LINE_SIZE);
1800 	m = roundup(m, PAGE_SIZE);
1801 	npages -= (m - (uintptr_t)mem) / PAGE_SIZE;
1802 	mem = (void *)m;
1803 
1804 	/* "manually" create the initial zone */
1805 	memset(&args, 0, sizeof(args));
1806 	args.name = "UMA Kegs";
1807 	args.size = ksize;
1808 	args.ctor = keg_ctor;
1809 	args.dtor = keg_dtor;
1810 	args.uminit = zero_init;
1811 	args.fini = NULL;
1812 	args.keg = masterkeg;
1813 	args.align = 32 - 1;
1814 	args.flags = UMA_ZFLAG_INTERNAL;
1815 	zone_ctor(kegs, zsize, &args, M_WAITOK);
1816 
1817 	mtx_init(&uma_boot_pages_mtx, "UMA boot pages", NULL, MTX_DEF);
1818 	bootmem = mem;
1819 	boot_pages = npages;
1820 
1821 	args.name = "UMA Zones";
1822 	args.size = sizeof(struct uma_zone) +
1823 	    (sizeof(struct uma_cache) * (mp_maxid + 1)) +
1824 	    (sizeof(struct uma_zone_domain) * vm_ndomains);
1825 	args.ctor = zone_ctor;
1826 	args.dtor = zone_dtor;
1827 	args.uminit = zero_init;
1828 	args.fini = NULL;
1829 	args.keg = NULL;
1830 	args.align = 32 - 1;
1831 	args.flags = UMA_ZFLAG_INTERNAL;
1832 	zone_ctor(zones, zsize, &args, M_WAITOK);
1833 
1834 	/* Now make a zone for slab headers */
1835 	slabzone = uma_zcreate("UMA Slabs",
1836 				sizeof(struct uma_slab),
1837 				NULL, NULL, NULL, NULL,
1838 				UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
1839 
1840 	hashzone = uma_zcreate("UMA Hash",
1841 	    sizeof(struct slabhead *) * UMA_HASH_SIZE_INIT,
1842 	    NULL, NULL, NULL, NULL,
1843 	    UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
1844 
1845 	bucket_init();
1846 
1847 	booted = UMA_STARTUP;
1848 }
1849 
1850 /* see uma.h */
1851 void
1852 uma_startup2(void)
1853 {
1854 	booted = UMA_STARTUP2;
1855 	bucket_enable();
1856 	sx_init(&uma_drain_lock, "umadrain");
1857 }
1858 
1859 /*
1860  * Initialize our callout handle
1861  *
1862  */
1863 
1864 static void
1865 uma_startup3(void)
1866 {
1867 
1868 	callout_init(&uma_callout, 1);
1869 	callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL);
1870 }
1871 
1872 static uma_keg_t
1873 uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit, uma_fini fini,
1874 		int align, uint32_t flags)
1875 {
1876 	struct uma_kctor_args args;
1877 
1878 	args.size = size;
1879 	args.uminit = uminit;
1880 	args.fini = fini;
1881 	args.align = (align == UMA_ALIGN_CACHE) ? uma_align_cache : align;
1882 	args.flags = flags;
1883 	args.zone = zone;
1884 	return (zone_alloc_item(kegs, &args, UMA_ANYDOMAIN, M_WAITOK));
1885 }
1886 
1887 /* See uma.h */
1888 void
1889 uma_set_align(int align)
1890 {
1891 
1892 	if (align != UMA_ALIGN_CACHE)
1893 		uma_align_cache = align;
1894 }
1895 
1896 /* See uma.h */
1897 uma_zone_t
1898 uma_zcreate(const char *name, size_t size, uma_ctor ctor, uma_dtor dtor,
1899 		uma_init uminit, uma_fini fini, int align, uint32_t flags)
1900 
1901 {
1902 	struct uma_zctor_args args;
1903 	uma_zone_t res;
1904 	bool locked;
1905 
1906 	KASSERT(powerof2(align + 1), ("invalid zone alignment %d for \"%s\"",
1907 	    align, name));
1908 
1909 	/* This stuff is essential for the zone ctor */
1910 	memset(&args, 0, sizeof(args));
1911 	args.name = name;
1912 	args.size = size;
1913 	args.ctor = ctor;
1914 	args.dtor = dtor;
1915 	args.uminit = uminit;
1916 	args.fini = fini;
1917 #ifdef  INVARIANTS
1918 	/*
1919 	 * If a zone is being created with an empty constructor and
1920 	 * destructor, pass UMA constructor/destructor which checks for
1921 	 * memory use after free.
1922 	 */
1923 	if ((!(flags & (UMA_ZONE_ZINIT | UMA_ZONE_NOFREE))) &&
1924 	    ctor == NULL && dtor == NULL && uminit == NULL && fini == NULL) {
1925 		args.ctor = trash_ctor;
1926 		args.dtor = trash_dtor;
1927 		args.uminit = trash_init;
1928 		args.fini = trash_fini;
1929 	}
1930 #endif
1931 	args.align = align;
1932 	args.flags = flags;
1933 	args.keg = NULL;
1934 
1935 	if (booted < UMA_STARTUP2) {
1936 		locked = false;
1937 	} else {
1938 		sx_slock(&uma_drain_lock);
1939 		locked = true;
1940 	}
1941 	res = zone_alloc_item(zones, &args, UMA_ANYDOMAIN, M_WAITOK);
1942 	if (locked)
1943 		sx_sunlock(&uma_drain_lock);
1944 	return (res);
1945 }
1946 
1947 /* See uma.h */
1948 uma_zone_t
1949 uma_zsecond_create(char *name, uma_ctor ctor, uma_dtor dtor,
1950 		    uma_init zinit, uma_fini zfini, uma_zone_t master)
1951 {
1952 	struct uma_zctor_args args;
1953 	uma_keg_t keg;
1954 	uma_zone_t res;
1955 	bool locked;
1956 
1957 	keg = zone_first_keg(master);
1958 	memset(&args, 0, sizeof(args));
1959 	args.name = name;
1960 	args.size = keg->uk_size;
1961 	args.ctor = ctor;
1962 	args.dtor = dtor;
1963 	args.uminit = zinit;
1964 	args.fini = zfini;
1965 	args.align = keg->uk_align;
1966 	args.flags = keg->uk_flags | UMA_ZONE_SECONDARY;
1967 	args.keg = keg;
1968 
1969 	if (booted < UMA_STARTUP2) {
1970 		locked = false;
1971 	} else {
1972 		sx_slock(&uma_drain_lock);
1973 		locked = true;
1974 	}
1975 	/* XXX Attaches only one keg of potentially many. */
1976 	res = zone_alloc_item(zones, &args, UMA_ANYDOMAIN, M_WAITOK);
1977 	if (locked)
1978 		sx_sunlock(&uma_drain_lock);
1979 	return (res);
1980 }
1981 
1982 /* See uma.h */
1983 uma_zone_t
1984 uma_zcache_create(char *name, int size, uma_ctor ctor, uma_dtor dtor,
1985 		    uma_init zinit, uma_fini zfini, uma_import zimport,
1986 		    uma_release zrelease, void *arg, int flags)
1987 {
1988 	struct uma_zctor_args args;
1989 
1990 	memset(&args, 0, sizeof(args));
1991 	args.name = name;
1992 	args.size = size;
1993 	args.ctor = ctor;
1994 	args.dtor = dtor;
1995 	args.uminit = zinit;
1996 	args.fini = zfini;
1997 	args.import = zimport;
1998 	args.release = zrelease;
1999 	args.arg = arg;
2000 	args.align = 0;
2001 	args.flags = flags;
2002 
2003 	return (zone_alloc_item(zones, &args, UMA_ANYDOMAIN, M_WAITOK));
2004 }
2005 
2006 static void
2007 zone_lock_pair(uma_zone_t a, uma_zone_t b)
2008 {
2009 	if (a < b) {
2010 		ZONE_LOCK(a);
2011 		mtx_lock_flags(b->uz_lockptr, MTX_DUPOK);
2012 	} else {
2013 		ZONE_LOCK(b);
2014 		mtx_lock_flags(a->uz_lockptr, MTX_DUPOK);
2015 	}
2016 }
2017 
2018 static void
2019 zone_unlock_pair(uma_zone_t a, uma_zone_t b)
2020 {
2021 
2022 	ZONE_UNLOCK(a);
2023 	ZONE_UNLOCK(b);
2024 }
2025 
2026 int
2027 uma_zsecond_add(uma_zone_t zone, uma_zone_t master)
2028 {
2029 	uma_klink_t klink;
2030 	uma_klink_t kl;
2031 	int error;
2032 
2033 	error = 0;
2034 	klink = malloc(sizeof(*klink), M_TEMP, M_WAITOK | M_ZERO);
2035 
2036 	zone_lock_pair(zone, master);
2037 	/*
2038 	 * zone must use vtoslab() to resolve objects and must already be
2039 	 * a secondary.
2040 	 */
2041 	if ((zone->uz_flags & (UMA_ZONE_VTOSLAB | UMA_ZONE_SECONDARY))
2042 	    != (UMA_ZONE_VTOSLAB | UMA_ZONE_SECONDARY)) {
2043 		error = EINVAL;
2044 		goto out;
2045 	}
2046 	/*
2047 	 * The new master must also use vtoslab().
2048 	 */
2049 	if ((zone->uz_flags & UMA_ZONE_VTOSLAB) != UMA_ZONE_VTOSLAB) {
2050 		error = EINVAL;
2051 		goto out;
2052 	}
2053 
2054 	/*
2055 	 * The underlying object must be the same size.  rsize
2056 	 * may be different.
2057 	 */
2058 	if (master->uz_size != zone->uz_size) {
2059 		error = E2BIG;
2060 		goto out;
2061 	}
2062 	/*
2063 	 * Put it at the end of the list.
2064 	 */
2065 	klink->kl_keg = zone_first_keg(master);
2066 	LIST_FOREACH(kl, &zone->uz_kegs, kl_link) {
2067 		if (LIST_NEXT(kl, kl_link) == NULL) {
2068 			LIST_INSERT_AFTER(kl, klink, kl_link);
2069 			break;
2070 		}
2071 	}
2072 	klink = NULL;
2073 	zone->uz_flags |= UMA_ZFLAG_MULTI;
2074 	zone->uz_slab = zone_fetch_slab_multi;
2075 
2076 out:
2077 	zone_unlock_pair(zone, master);
2078 	if (klink != NULL)
2079 		free(klink, M_TEMP);
2080 
2081 	return (error);
2082 }
2083 
2084 
2085 /* See uma.h */
2086 void
2087 uma_zdestroy(uma_zone_t zone)
2088 {
2089 
2090 	sx_slock(&uma_drain_lock);
2091 	zone_free_item(zones, zone, NULL, SKIP_NONE);
2092 	sx_sunlock(&uma_drain_lock);
2093 }
2094 
2095 void
2096 uma_zwait(uma_zone_t zone)
2097 {
2098 	void *item;
2099 
2100 	item = uma_zalloc_arg(zone, NULL, M_WAITOK);
2101 	uma_zfree(zone, item);
2102 }
2103 
2104 /* See uma.h */
2105 void *
2106 uma_zalloc_arg(uma_zone_t zone, void *udata, int flags)
2107 {
2108 	uma_zone_domain_t zdom;
2109 	uma_bucket_t bucket;
2110 	uma_cache_t cache;
2111 	void *item;
2112 	int cpu, domain, lockfail;
2113 
2114 	/* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
2115 	random_harvest_fast_uma(&zone, sizeof(zone), 1, RANDOM_UMA);
2116 
2117 	/* This is the fast path allocation */
2118 	CTR4(KTR_UMA, "uma_zalloc_arg thread %x zone %s(%p) flags %d",
2119 	    curthread, zone->uz_name, zone, flags);
2120 
2121 	if (flags & M_WAITOK) {
2122 		WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
2123 		    "uma_zalloc_arg: zone \"%s\"", zone->uz_name);
2124 	}
2125 	KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
2126 	    ("uma_zalloc_arg: called with spinlock or critical section held"));
2127 
2128 #ifdef DEBUG_MEMGUARD
2129 	if (memguard_cmp_zone(zone)) {
2130 		item = memguard_alloc(zone->uz_size, flags);
2131 		if (item != NULL) {
2132 			if (zone->uz_init != NULL &&
2133 			    zone->uz_init(item, zone->uz_size, flags) != 0)
2134 				return (NULL);
2135 			if (zone->uz_ctor != NULL &&
2136 			    zone->uz_ctor(item, zone->uz_size, udata,
2137 			    flags) != 0) {
2138 			    	zone->uz_fini(item, zone->uz_size);
2139 				return (NULL);
2140 			}
2141 			return (item);
2142 		}
2143 		/* This is unfortunate but should not be fatal. */
2144 	}
2145 #endif
2146 	/*
2147 	 * If possible, allocate from the per-CPU cache.  There are two
2148 	 * requirements for safe access to the per-CPU cache: (1) the thread
2149 	 * accessing the cache must not be preempted or yield during access,
2150 	 * and (2) the thread must not migrate CPUs without switching which
2151 	 * cache it accesses.  We rely on a critical section to prevent
2152 	 * preemption and migration.  We release the critical section in
2153 	 * order to acquire the zone mutex if we are unable to allocate from
2154 	 * the current cache; when we re-acquire the critical section, we
2155 	 * must detect and handle migration if it has occurred.
2156 	 */
2157 	critical_enter();
2158 	cpu = curcpu;
2159 	cache = &zone->uz_cpu[cpu];
2160 
2161 zalloc_start:
2162 	bucket = cache->uc_allocbucket;
2163 	if (bucket != NULL && bucket->ub_cnt > 0) {
2164 		bucket->ub_cnt--;
2165 		item = bucket->ub_bucket[bucket->ub_cnt];
2166 #ifdef INVARIANTS
2167 		bucket->ub_bucket[bucket->ub_cnt] = NULL;
2168 #endif
2169 		KASSERT(item != NULL, ("uma_zalloc: Bucket pointer mangled."));
2170 		cache->uc_allocs++;
2171 		critical_exit();
2172 		if (zone->uz_ctor != NULL &&
2173 		    zone->uz_ctor(item, zone->uz_size, udata, flags) != 0) {
2174 			atomic_add_long(&zone->uz_fails, 1);
2175 			zone_free_item(zone, item, udata, SKIP_DTOR);
2176 			return (NULL);
2177 		}
2178 #ifdef INVARIANTS
2179 		uma_dbg_alloc(zone, NULL, item);
2180 #endif
2181 		if (flags & M_ZERO)
2182 			uma_zero_item(item, zone);
2183 		return (item);
2184 	}
2185 
2186 	/*
2187 	 * We have run out of items in our alloc bucket.
2188 	 * See if we can switch with our free bucket.
2189 	 */
2190 	bucket = cache->uc_freebucket;
2191 	if (bucket != NULL && bucket->ub_cnt > 0) {
2192 		CTR2(KTR_UMA,
2193 		    "uma_zalloc: zone %s(%p) swapping empty with alloc",
2194 		    zone->uz_name, zone);
2195 		cache->uc_freebucket = cache->uc_allocbucket;
2196 		cache->uc_allocbucket = bucket;
2197 		goto zalloc_start;
2198 	}
2199 
2200 	/*
2201 	 * Discard any empty allocation bucket while we hold no locks.
2202 	 */
2203 	bucket = cache->uc_allocbucket;
2204 	cache->uc_allocbucket = NULL;
2205 	critical_exit();
2206 	if (bucket != NULL)
2207 		bucket_free(zone, bucket, udata);
2208 
2209 	if (zone->uz_flags & UMA_ZONE_NUMA)
2210 		domain = PCPU_GET(domain);
2211 	else
2212 		domain = UMA_ANYDOMAIN;
2213 
2214 	/* Short-circuit for zones without buckets and low memory. */
2215 	if (zone->uz_count == 0 || bucketdisable)
2216 		goto zalloc_item;
2217 
2218 	/*
2219 	 * Attempt to retrieve the item from the per-CPU cache has failed, so
2220 	 * we must go back to the zone.  This requires the zone lock, so we
2221 	 * must drop the critical section, then re-acquire it when we go back
2222 	 * to the cache.  Since the critical section is released, we may be
2223 	 * preempted or migrate.  As such, make sure not to maintain any
2224 	 * thread-local state specific to the cache from prior to releasing
2225 	 * the critical section.
2226 	 */
2227 	lockfail = 0;
2228 	if (ZONE_TRYLOCK(zone) == 0) {
2229 		/* Record contention to size the buckets. */
2230 		ZONE_LOCK(zone);
2231 		lockfail = 1;
2232 	}
2233 	critical_enter();
2234 	cpu = curcpu;
2235 	cache = &zone->uz_cpu[cpu];
2236 
2237 	/*
2238 	 * Since we have locked the zone we may as well send back our stats.
2239 	 */
2240 	atomic_add_long(&zone->uz_allocs, cache->uc_allocs);
2241 	atomic_add_long(&zone->uz_frees, cache->uc_frees);
2242 	cache->uc_allocs = 0;
2243 	cache->uc_frees = 0;
2244 
2245 	/* See if we lost the race to fill the cache. */
2246 	if (cache->uc_allocbucket != NULL) {
2247 		ZONE_UNLOCK(zone);
2248 		goto zalloc_start;
2249 	}
2250 
2251 	/*
2252 	 * Check the zone's cache of buckets.
2253 	 */
2254 	if (domain == UMA_ANYDOMAIN)
2255 		zdom = &zone->uz_domain[0];
2256 	else
2257 		zdom = &zone->uz_domain[domain];
2258 	if ((bucket = LIST_FIRST(&zdom->uzd_buckets)) != NULL) {
2259 		KASSERT(bucket->ub_cnt != 0,
2260 		    ("uma_zalloc_arg: Returning an empty bucket."));
2261 
2262 		LIST_REMOVE(bucket, ub_link);
2263 		cache->uc_allocbucket = bucket;
2264 		ZONE_UNLOCK(zone);
2265 		goto zalloc_start;
2266 	}
2267 	/* We are no longer associated with this CPU. */
2268 	critical_exit();
2269 
2270 	/*
2271 	 * We bump the uz count when the cache size is insufficient to
2272 	 * handle the working set.
2273 	 */
2274 	if (lockfail && zone->uz_count < BUCKET_MAX)
2275 		zone->uz_count++;
2276 	ZONE_UNLOCK(zone);
2277 
2278 	/*
2279 	 * Now lets just fill a bucket and put it on the free list.  If that
2280 	 * works we'll restart the allocation from the beginning and it
2281 	 * will use the just filled bucket.
2282 	 */
2283 	bucket = zone_alloc_bucket(zone, udata, domain, flags);
2284 	CTR3(KTR_UMA, "uma_zalloc: zone %s(%p) bucket zone returned %p",
2285 	    zone->uz_name, zone, bucket);
2286 	if (bucket != NULL) {
2287 		ZONE_LOCK(zone);
2288 		critical_enter();
2289 		cpu = curcpu;
2290 		cache = &zone->uz_cpu[cpu];
2291 		/*
2292 		 * See if we lost the race or were migrated.  Cache the
2293 		 * initialized bucket to make this less likely or claim
2294 		 * the memory directly.
2295 		 */
2296 		if (cache->uc_allocbucket != NULL ||
2297 		    (zone->uz_flags & UMA_ZONE_NUMA &&
2298 		    domain != PCPU_GET(domain)))
2299 			LIST_INSERT_HEAD(&zdom->uzd_buckets, bucket, ub_link);
2300 		else
2301 			cache->uc_allocbucket = bucket;
2302 		ZONE_UNLOCK(zone);
2303 		goto zalloc_start;
2304 	}
2305 
2306 	/*
2307 	 * We may not be able to get a bucket so return an actual item.
2308 	 */
2309 zalloc_item:
2310 	item = zone_alloc_item(zone, udata, domain, flags);
2311 
2312 	return (item);
2313 }
2314 
2315 void *
2316 uma_zalloc_domain(uma_zone_t zone, void *udata, int domain, int flags)
2317 {
2318 
2319 	/* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
2320 	random_harvest_fast_uma(&zone, sizeof(zone), 1, RANDOM_UMA);
2321 
2322 	/* This is the fast path allocation */
2323 	CTR5(KTR_UMA,
2324 	    "uma_zalloc_domain thread %x zone %s(%p) domain %d flags %d",
2325 	    curthread, zone->uz_name, zone, domain, flags);
2326 
2327 	if (flags & M_WAITOK) {
2328 		WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
2329 		    "uma_zalloc_domain: zone \"%s\"", zone->uz_name);
2330 	}
2331 	KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
2332 	    ("uma_zalloc_domain: called with spinlock or critical section held"));
2333 
2334 	return (zone_alloc_item(zone, udata, domain, flags));
2335 }
2336 
2337 /*
2338  * Find a slab with some space.  Prefer slabs that are partially used over those
2339  * that are totally full.  This helps to reduce fragmentation.
2340  *
2341  * If 'rr' is 1, search all domains starting from 'domain'.  Otherwise check
2342  * only 'domain'.
2343  */
2344 static uma_slab_t
2345 keg_first_slab(uma_keg_t keg, int domain, int rr)
2346 {
2347 	uma_domain_t dom;
2348 	uma_slab_t slab;
2349 	int start;
2350 
2351 	KASSERT(domain >= 0 && domain < vm_ndomains,
2352 	    ("keg_first_slab: domain %d out of range", domain));
2353 
2354 	slab = NULL;
2355 	start = domain;
2356 	do {
2357 		dom = &keg->uk_domain[domain];
2358 		if (!LIST_EMPTY(&dom->ud_part_slab))
2359 			return (LIST_FIRST(&dom->ud_part_slab));
2360 		if (!LIST_EMPTY(&dom->ud_free_slab)) {
2361 			slab = LIST_FIRST(&dom->ud_free_slab);
2362 			LIST_REMOVE(slab, us_link);
2363 			LIST_INSERT_HEAD(&dom->ud_part_slab, slab, us_link);
2364 			return (slab);
2365 		}
2366 		if (rr)
2367 			domain = (domain + 1) % vm_ndomains;
2368 	} while (domain != start);
2369 
2370 	return (NULL);
2371 }
2372 
2373 static uma_slab_t
2374 keg_fetch_slab(uma_keg_t keg, uma_zone_t zone, int rdomain, int flags)
2375 {
2376 	uma_domain_t dom;
2377 	uma_slab_t slab;
2378 	int allocflags, domain, reserve, rr, start;
2379 
2380 	mtx_assert(&keg->uk_lock, MA_OWNED);
2381 	slab = NULL;
2382 	reserve = 0;
2383 	allocflags = flags;
2384 	if ((flags & M_USE_RESERVE) == 0)
2385 		reserve = keg->uk_reserve;
2386 
2387 	/*
2388 	 * Round-robin for non first-touch zones when there is more than one
2389 	 * domain.
2390 	 */
2391 	if (vm_ndomains == 1)
2392 		rdomain = 0;
2393 	rr = rdomain == UMA_ANYDOMAIN;
2394 	if (rr) {
2395 		keg->uk_cursor = (keg->uk_cursor + 1) % vm_ndomains;
2396 		domain = start = keg->uk_cursor;
2397 		/* Only block on the second pass. */
2398 		if ((flags & (M_WAITOK | M_NOVM)) == M_WAITOK)
2399 			allocflags = (allocflags & ~M_WAITOK) | M_NOWAIT;
2400 	} else
2401 		domain = start = rdomain;
2402 
2403 again:
2404 	do {
2405 		if (keg->uk_free > reserve &&
2406 		    (slab = keg_first_slab(keg, domain, rr)) != NULL) {
2407 			MPASS(slab->us_keg == keg);
2408 			return (slab);
2409 		}
2410 
2411 		/*
2412 		 * M_NOVM means don't ask at all!
2413 		 */
2414 		if (flags & M_NOVM)
2415 			break;
2416 
2417 		if (keg->uk_maxpages && keg->uk_pages >= keg->uk_maxpages) {
2418 			keg->uk_flags |= UMA_ZFLAG_FULL;
2419 			/*
2420 			 * If this is not a multi-zone, set the FULL bit.
2421 			 * Otherwise slab_multi() takes care of it.
2422 			 */
2423 			if ((zone->uz_flags & UMA_ZFLAG_MULTI) == 0) {
2424 				zone->uz_flags |= UMA_ZFLAG_FULL;
2425 				zone_log_warning(zone);
2426 				zone_maxaction(zone);
2427 			}
2428 			if (flags & M_NOWAIT)
2429 				return (NULL);
2430 			zone->uz_sleeps++;
2431 			msleep(keg, &keg->uk_lock, PVM, "keglimit", 0);
2432 			continue;
2433 		}
2434 		slab = keg_alloc_slab(keg, zone, domain, allocflags);
2435 		/*
2436 		 * If we got a slab here it's safe to mark it partially used
2437 		 * and return.  We assume that the caller is going to remove
2438 		 * at least one item.
2439 		 */
2440 		if (slab) {
2441 			MPASS(slab->us_keg == keg);
2442 			dom = &keg->uk_domain[slab->us_domain];
2443 			LIST_INSERT_HEAD(&dom->ud_part_slab, slab, us_link);
2444 			return (slab);
2445 		}
2446 		if (rr) {
2447 			keg->uk_cursor = (keg->uk_cursor + 1) % vm_ndomains;
2448 			domain = keg->uk_cursor;
2449 		}
2450 	} while (domain != start);
2451 
2452 	/* Retry domain scan with blocking. */
2453 	if (allocflags != flags) {
2454 		allocflags = flags;
2455 		goto again;
2456 	}
2457 
2458 	/*
2459 	 * We might not have been able to get a slab but another cpu
2460 	 * could have while we were unlocked.  Check again before we
2461 	 * fail.
2462 	 */
2463 	if (keg->uk_free > reserve &&
2464 	    (slab = keg_first_slab(keg, domain, rr)) != NULL) {
2465 		MPASS(slab->us_keg == keg);
2466 		return (slab);
2467 	}
2468 	return (NULL);
2469 }
2470 
2471 static uma_slab_t
2472 zone_fetch_slab(uma_zone_t zone, uma_keg_t keg, int domain, int flags)
2473 {
2474 	uma_slab_t slab;
2475 
2476 	if (keg == NULL) {
2477 		keg = zone_first_keg(zone);
2478 		KEG_LOCK(keg);
2479 	}
2480 
2481 	for (;;) {
2482 		slab = keg_fetch_slab(keg, zone, domain, flags);
2483 		if (slab)
2484 			return (slab);
2485 		if (flags & (M_NOWAIT | M_NOVM))
2486 			break;
2487 	}
2488 	KEG_UNLOCK(keg);
2489 	return (NULL);
2490 }
2491 
2492 /*
2493  * uma_zone_fetch_slab_multi:  Fetches a slab from one available keg.  Returns
2494  * with the keg locked.  On NULL no lock is held.
2495  *
2496  * The last pointer is used to seed the search.  It is not required.
2497  */
2498 static uma_slab_t
2499 zone_fetch_slab_multi(uma_zone_t zone, uma_keg_t last, int domain, int rflags)
2500 {
2501 	uma_klink_t klink;
2502 	uma_slab_t slab;
2503 	uma_keg_t keg;
2504 	int flags;
2505 	int empty;
2506 	int full;
2507 
2508 	/*
2509 	 * Don't wait on the first pass.  This will skip limit tests
2510 	 * as well.  We don't want to block if we can find a provider
2511 	 * without blocking.
2512 	 */
2513 	flags = (rflags & ~M_WAITOK) | M_NOWAIT;
2514 	/*
2515 	 * Use the last slab allocated as a hint for where to start
2516 	 * the search.
2517 	 */
2518 	if (last != NULL) {
2519 		slab = keg_fetch_slab(last, zone, domain, flags);
2520 		if (slab)
2521 			return (slab);
2522 		KEG_UNLOCK(last);
2523 	}
2524 	/*
2525 	 * Loop until we have a slab incase of transient failures
2526 	 * while M_WAITOK is specified.  I'm not sure this is 100%
2527 	 * required but we've done it for so long now.
2528 	 */
2529 	for (;;) {
2530 		empty = 0;
2531 		full = 0;
2532 		/*
2533 		 * Search the available kegs for slabs.  Be careful to hold the
2534 		 * correct lock while calling into the keg layer.
2535 		 */
2536 		LIST_FOREACH(klink, &zone->uz_kegs, kl_link) {
2537 			keg = klink->kl_keg;
2538 			KEG_LOCK(keg);
2539 			if ((keg->uk_flags & UMA_ZFLAG_FULL) == 0) {
2540 				slab = keg_fetch_slab(keg, zone, domain, flags);
2541 				if (slab)
2542 					return (slab);
2543 			}
2544 			if (keg->uk_flags & UMA_ZFLAG_FULL)
2545 				full++;
2546 			else
2547 				empty++;
2548 			KEG_UNLOCK(keg);
2549 		}
2550 		if (rflags & (M_NOWAIT | M_NOVM))
2551 			break;
2552 		flags = rflags;
2553 		/*
2554 		 * All kegs are full.  XXX We can't atomically check all kegs
2555 		 * and sleep so just sleep for a short period and retry.
2556 		 */
2557 		if (full && !empty) {
2558 			ZONE_LOCK(zone);
2559 			zone->uz_flags |= UMA_ZFLAG_FULL;
2560 			zone->uz_sleeps++;
2561 			zone_log_warning(zone);
2562 			zone_maxaction(zone);
2563 			msleep(zone, zone->uz_lockptr, PVM,
2564 			    "zonelimit", hz/100);
2565 			zone->uz_flags &= ~UMA_ZFLAG_FULL;
2566 			ZONE_UNLOCK(zone);
2567 			continue;
2568 		}
2569 	}
2570 	return (NULL);
2571 }
2572 
2573 static void *
2574 slab_alloc_item(uma_keg_t keg, uma_slab_t slab)
2575 {
2576 	uma_domain_t dom;
2577 	void *item;
2578 	uint8_t freei;
2579 
2580 	MPASS(keg == slab->us_keg);
2581 	mtx_assert(&keg->uk_lock, MA_OWNED);
2582 
2583 	freei = BIT_FFS(SLAB_SETSIZE, &slab->us_free) - 1;
2584 	BIT_CLR(SLAB_SETSIZE, freei, &slab->us_free);
2585 	item = slab->us_data + (keg->uk_rsize * freei);
2586 	slab->us_freecount--;
2587 	keg->uk_free--;
2588 
2589 	/* Move this slab to the full list */
2590 	if (slab->us_freecount == 0) {
2591 		LIST_REMOVE(slab, us_link);
2592 		dom = &keg->uk_domain[slab->us_domain];
2593 		LIST_INSERT_HEAD(&dom->ud_full_slab, slab, us_link);
2594 	}
2595 
2596 	return (item);
2597 }
2598 
2599 static int
2600 zone_import(uma_zone_t zone, void **bucket, int max, int domain, int flags)
2601 {
2602 	uma_slab_t slab;
2603 	uma_keg_t keg;
2604 	int stripe;
2605 	int i;
2606 
2607 	slab = NULL;
2608 	keg = NULL;
2609 	/* Try to keep the buckets totally full */
2610 	for (i = 0; i < max; ) {
2611 		if ((slab = zone->uz_slab(zone, keg, domain, flags)) == NULL)
2612 			break;
2613 		keg = slab->us_keg;
2614 		stripe = howmany(max, vm_ndomains);
2615 		while (slab->us_freecount && i < max) {
2616 			bucket[i++] = slab_alloc_item(keg, slab);
2617 			if (keg->uk_free <= keg->uk_reserve)
2618 				break;
2619 #ifdef NUMA
2620 			/*
2621 			 * If the zone is striped we pick a new slab for every
2622 			 * N allocations.  Eliminating this conditional will
2623 			 * instead pick a new domain for each bucket rather
2624 			 * than stripe within each bucket.  The current option
2625 			 * produces more fragmentation and requires more cpu
2626 			 * time but yields better distribution.
2627 			 */
2628 			if ((zone->uz_flags & UMA_ZONE_NUMA) == 0 &&
2629 			    vm_ndomains > 1 && --stripe == 0)
2630 				break;
2631 #endif
2632 		}
2633 		/* Don't block if we allocated any successfully. */
2634 		flags &= ~M_WAITOK;
2635 		flags |= M_NOWAIT;
2636 	}
2637 	if (slab != NULL)
2638 		KEG_UNLOCK(keg);
2639 
2640 	return i;
2641 }
2642 
2643 static uma_bucket_t
2644 zone_alloc_bucket(uma_zone_t zone, void *udata, int domain, int flags)
2645 {
2646 	uma_bucket_t bucket;
2647 	int max;
2648 
2649 	/* Don't wait for buckets, preserve caller's NOVM setting. */
2650 	bucket = bucket_alloc(zone, udata, M_NOWAIT | (flags & M_NOVM));
2651 	if (bucket == NULL)
2652 		return (NULL);
2653 
2654 	max = MIN(bucket->ub_entries, zone->uz_count);
2655 	bucket->ub_cnt = zone->uz_import(zone->uz_arg, bucket->ub_bucket,
2656 	    max, domain, flags);
2657 
2658 	/*
2659 	 * Initialize the memory if necessary.
2660 	 */
2661 	if (bucket->ub_cnt != 0 && zone->uz_init != NULL) {
2662 		int i;
2663 
2664 		for (i = 0; i < bucket->ub_cnt; i++)
2665 			if (zone->uz_init(bucket->ub_bucket[i], zone->uz_size,
2666 			    flags) != 0)
2667 				break;
2668 		/*
2669 		 * If we couldn't initialize the whole bucket, put the
2670 		 * rest back onto the freelist.
2671 		 */
2672 		if (i != bucket->ub_cnt) {
2673 			zone->uz_release(zone->uz_arg, &bucket->ub_bucket[i],
2674 			    bucket->ub_cnt - i);
2675 #ifdef INVARIANTS
2676 			bzero(&bucket->ub_bucket[i],
2677 			    sizeof(void *) * (bucket->ub_cnt - i));
2678 #endif
2679 			bucket->ub_cnt = i;
2680 		}
2681 	}
2682 
2683 	if (bucket->ub_cnt == 0) {
2684 		bucket_free(zone, bucket, udata);
2685 		atomic_add_long(&zone->uz_fails, 1);
2686 		return (NULL);
2687 	}
2688 
2689 	return (bucket);
2690 }
2691 
2692 /*
2693  * Allocates a single item from a zone.
2694  *
2695  * Arguments
2696  *	zone   The zone to alloc for.
2697  *	udata  The data to be passed to the constructor.
2698  *	domain The domain to allocate from or UMA_ANYDOMAIN.
2699  *	flags  M_WAITOK, M_NOWAIT, M_ZERO.
2700  *
2701  * Returns
2702  *	NULL if there is no memory and M_NOWAIT is set
2703  *	An item if successful
2704  */
2705 
2706 static void *
2707 zone_alloc_item(uma_zone_t zone, void *udata, int domain, int flags)
2708 {
2709 	void *item;
2710 
2711 	item = NULL;
2712 
2713 	if (zone->uz_import(zone->uz_arg, &item, 1, domain, flags) != 1)
2714 		goto fail;
2715 	atomic_add_long(&zone->uz_allocs, 1);
2716 
2717 	/*
2718 	 * We have to call both the zone's init (not the keg's init)
2719 	 * and the zone's ctor.  This is because the item is going from
2720 	 * a keg slab directly to the user, and the user is expecting it
2721 	 * to be both zone-init'd as well as zone-ctor'd.
2722 	 */
2723 	if (zone->uz_init != NULL) {
2724 		if (zone->uz_init(item, zone->uz_size, flags) != 0) {
2725 			zone_free_item(zone, item, udata, SKIP_FINI);
2726 			goto fail;
2727 		}
2728 	}
2729 	if (zone->uz_ctor != NULL) {
2730 		if (zone->uz_ctor(item, zone->uz_size, udata, flags) != 0) {
2731 			zone_free_item(zone, item, udata, SKIP_DTOR);
2732 			goto fail;
2733 		}
2734 	}
2735 #ifdef INVARIANTS
2736 	uma_dbg_alloc(zone, NULL, item);
2737 #endif
2738 	if (flags & M_ZERO)
2739 		uma_zero_item(item, zone);
2740 
2741 	CTR3(KTR_UMA, "zone_alloc_item item %p from %s(%p)", item,
2742 	    zone->uz_name, zone);
2743 
2744 	return (item);
2745 
2746 fail:
2747 	CTR2(KTR_UMA, "zone_alloc_item failed from %s(%p)",
2748 	    zone->uz_name, zone);
2749 	atomic_add_long(&zone->uz_fails, 1);
2750 	return (NULL);
2751 }
2752 
2753 /* See uma.h */
2754 void
2755 uma_zfree_arg(uma_zone_t zone, void *item, void *udata)
2756 {
2757 	uma_cache_t cache;
2758 	uma_bucket_t bucket;
2759 	uma_zone_domain_t zdom;
2760 	int cpu, domain, lockfail;
2761 
2762 	/* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
2763 	random_harvest_fast_uma(&zone, sizeof(zone), 1, RANDOM_UMA);
2764 
2765 	CTR2(KTR_UMA, "uma_zfree_arg thread %x zone %s", curthread,
2766 	    zone->uz_name);
2767 
2768 	KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
2769 	    ("uma_zfree_arg: called with spinlock or critical section held"));
2770 
2771         /* uma_zfree(..., NULL) does nothing, to match free(9). */
2772         if (item == NULL)
2773                 return;
2774 #ifdef DEBUG_MEMGUARD
2775 	if (is_memguard_addr(item)) {
2776 		if (zone->uz_dtor != NULL)
2777 			zone->uz_dtor(item, zone->uz_size, udata);
2778 		if (zone->uz_fini != NULL)
2779 			zone->uz_fini(item, zone->uz_size);
2780 		memguard_free(item);
2781 		return;
2782 	}
2783 #endif
2784 #ifdef INVARIANTS
2785 	if (zone->uz_flags & UMA_ZONE_MALLOC)
2786 		uma_dbg_free(zone, udata, item);
2787 	else
2788 		uma_dbg_free(zone, NULL, item);
2789 #endif
2790 	if (zone->uz_dtor != NULL)
2791 		zone->uz_dtor(item, zone->uz_size, udata);
2792 
2793 	/*
2794 	 * The race here is acceptable.  If we miss it we'll just have to wait
2795 	 * a little longer for the limits to be reset.
2796 	 */
2797 	if (zone->uz_flags & UMA_ZFLAG_FULL)
2798 		goto zfree_item;
2799 
2800 	/*
2801 	 * If possible, free to the per-CPU cache.  There are two
2802 	 * requirements for safe access to the per-CPU cache: (1) the thread
2803 	 * accessing the cache must not be preempted or yield during access,
2804 	 * and (2) the thread must not migrate CPUs without switching which
2805 	 * cache it accesses.  We rely on a critical section to prevent
2806 	 * preemption and migration.  We release the critical section in
2807 	 * order to acquire the zone mutex if we are unable to free to the
2808 	 * current cache; when we re-acquire the critical section, we must
2809 	 * detect and handle migration if it has occurred.
2810 	 */
2811 zfree_restart:
2812 	critical_enter();
2813 	cpu = curcpu;
2814 	cache = &zone->uz_cpu[cpu];
2815 
2816 zfree_start:
2817 	/*
2818 	 * Try to free into the allocbucket first to give LIFO ordering
2819 	 * for cache-hot datastructures.  Spill over into the freebucket
2820 	 * if necessary.  Alloc will swap them if one runs dry.
2821 	 */
2822 	bucket = cache->uc_allocbucket;
2823 	if (bucket == NULL || bucket->ub_cnt >= bucket->ub_entries)
2824 		bucket = cache->uc_freebucket;
2825 	if (bucket != NULL && bucket->ub_cnt < bucket->ub_entries) {
2826 		KASSERT(bucket->ub_bucket[bucket->ub_cnt] == NULL,
2827 		    ("uma_zfree: Freeing to non free bucket index."));
2828 		bucket->ub_bucket[bucket->ub_cnt] = item;
2829 		bucket->ub_cnt++;
2830 		cache->uc_frees++;
2831 		critical_exit();
2832 		return;
2833 	}
2834 
2835 	/*
2836 	 * We must go back the zone, which requires acquiring the zone lock,
2837 	 * which in turn means we must release and re-acquire the critical
2838 	 * section.  Since the critical section is released, we may be
2839 	 * preempted or migrate.  As such, make sure not to maintain any
2840 	 * thread-local state specific to the cache from prior to releasing
2841 	 * the critical section.
2842 	 */
2843 	critical_exit();
2844 	if (zone->uz_count == 0 || bucketdisable)
2845 		goto zfree_item;
2846 
2847 	lockfail = 0;
2848 	if (ZONE_TRYLOCK(zone) == 0) {
2849 		/* Record contention to size the buckets. */
2850 		ZONE_LOCK(zone);
2851 		lockfail = 1;
2852 	}
2853 	critical_enter();
2854 	cpu = curcpu;
2855 	cache = &zone->uz_cpu[cpu];
2856 
2857 	/*
2858 	 * Since we have locked the zone we may as well send back our stats.
2859 	 */
2860 	atomic_add_long(&zone->uz_allocs, cache->uc_allocs);
2861 	atomic_add_long(&zone->uz_frees, cache->uc_frees);
2862 	cache->uc_allocs = 0;
2863 	cache->uc_frees = 0;
2864 
2865 	bucket = cache->uc_freebucket;
2866 	if (bucket != NULL && bucket->ub_cnt < bucket->ub_entries) {
2867 		ZONE_UNLOCK(zone);
2868 		goto zfree_start;
2869 	}
2870 	cache->uc_freebucket = NULL;
2871 	/* We are no longer associated with this CPU. */
2872 	critical_exit();
2873 
2874 	if ((zone->uz_flags & UMA_ZONE_NUMA) != 0)
2875 		domain = PCPU_GET(domain);
2876 	else
2877 		domain = 0;
2878 	zdom = &zone->uz_domain[0];
2879 
2880 	/* Can we throw this on the zone full list? */
2881 	if (bucket != NULL) {
2882 		CTR3(KTR_UMA,
2883 		    "uma_zfree: zone %s(%p) putting bucket %p on free list",
2884 		    zone->uz_name, zone, bucket);
2885 		/* ub_cnt is pointing to the last free item */
2886 		KASSERT(bucket->ub_cnt != 0,
2887 		    ("uma_zfree: Attempting to insert an empty bucket onto the full list.\n"));
2888 		LIST_INSERT_HEAD(&zdom->uzd_buckets, bucket, ub_link);
2889 	}
2890 
2891 	/*
2892 	 * We bump the uz count when the cache size is insufficient to
2893 	 * handle the working set.
2894 	 */
2895 	if (lockfail && zone->uz_count < BUCKET_MAX)
2896 		zone->uz_count++;
2897 	ZONE_UNLOCK(zone);
2898 
2899 	bucket = bucket_alloc(zone, udata, M_NOWAIT);
2900 	CTR3(KTR_UMA, "uma_zfree: zone %s(%p) allocated bucket %p",
2901 	    zone->uz_name, zone, bucket);
2902 	if (bucket) {
2903 		critical_enter();
2904 		cpu = curcpu;
2905 		cache = &zone->uz_cpu[cpu];
2906 		if (cache->uc_freebucket == NULL &&
2907 		    ((zone->uz_flags & UMA_ZONE_NUMA) == 0 ||
2908 		    domain == PCPU_GET(domain))) {
2909 			cache->uc_freebucket = bucket;
2910 			goto zfree_start;
2911 		}
2912 		/*
2913 		 * We lost the race, start over.  We have to drop our
2914 		 * critical section to free the bucket.
2915 		 */
2916 		critical_exit();
2917 		bucket_free(zone, bucket, udata);
2918 		goto zfree_restart;
2919 	}
2920 
2921 	/*
2922 	 * If nothing else caught this, we'll just do an internal free.
2923 	 */
2924 zfree_item:
2925 	zone_free_item(zone, item, udata, SKIP_DTOR);
2926 
2927 	return;
2928 }
2929 
2930 void
2931 uma_zfree_domain(uma_zone_t zone, void *item, void *udata)
2932 {
2933 
2934 	/* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
2935 	random_harvest_fast_uma(&zone, sizeof(zone), 1, RANDOM_UMA);
2936 
2937 	CTR2(KTR_UMA, "uma_zfree_domain thread %x zone %s", curthread,
2938 	    zone->uz_name);
2939 
2940 	KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
2941 	    ("uma_zfree_domain: called with spinlock or critical section held"));
2942 
2943         /* uma_zfree(..., NULL) does nothing, to match free(9). */
2944         if (item == NULL)
2945                 return;
2946 	zone_free_item(zone, item, udata, SKIP_NONE);
2947 }
2948 
2949 static void
2950 slab_free_item(uma_keg_t keg, uma_slab_t slab, void *item)
2951 {
2952 	uma_domain_t dom;
2953 	uint8_t freei;
2954 
2955 	mtx_assert(&keg->uk_lock, MA_OWNED);
2956 	MPASS(keg == slab->us_keg);
2957 
2958 	dom = &keg->uk_domain[slab->us_domain];
2959 
2960 	/* Do we need to remove from any lists? */
2961 	if (slab->us_freecount+1 == keg->uk_ipers) {
2962 		LIST_REMOVE(slab, us_link);
2963 		LIST_INSERT_HEAD(&dom->ud_free_slab, slab, us_link);
2964 	} else if (slab->us_freecount == 0) {
2965 		LIST_REMOVE(slab, us_link);
2966 		LIST_INSERT_HEAD(&dom->ud_part_slab, slab, us_link);
2967 	}
2968 
2969 	/* Slab management. */
2970 	freei = ((uintptr_t)item - (uintptr_t)slab->us_data) / keg->uk_rsize;
2971 	BIT_SET(SLAB_SETSIZE, freei, &slab->us_free);
2972 	slab->us_freecount++;
2973 
2974 	/* Keg statistics. */
2975 	keg->uk_free++;
2976 }
2977 
2978 static void
2979 zone_release(uma_zone_t zone, void **bucket, int cnt)
2980 {
2981 	void *item;
2982 	uma_slab_t slab;
2983 	uma_keg_t keg;
2984 	uint8_t *mem;
2985 	int clearfull;
2986 	int i;
2987 
2988 	clearfull = 0;
2989 	keg = zone_first_keg(zone);
2990 	KEG_LOCK(keg);
2991 	for (i = 0; i < cnt; i++) {
2992 		item = bucket[i];
2993 		if (!(zone->uz_flags & UMA_ZONE_VTOSLAB)) {
2994 			mem = (uint8_t *)((uintptr_t)item & (~UMA_SLAB_MASK));
2995 			if (zone->uz_flags & UMA_ZONE_HASH) {
2996 				slab = hash_sfind(&keg->uk_hash, mem);
2997 			} else {
2998 				mem += keg->uk_pgoff;
2999 				slab = (uma_slab_t)mem;
3000 			}
3001 		} else {
3002 			slab = vtoslab((vm_offset_t)item);
3003 			if (slab->us_keg != keg) {
3004 				KEG_UNLOCK(keg);
3005 				keg = slab->us_keg;
3006 				KEG_LOCK(keg);
3007 			}
3008 		}
3009 		slab_free_item(keg, slab, item);
3010 		if (keg->uk_flags & UMA_ZFLAG_FULL) {
3011 			if (keg->uk_pages < keg->uk_maxpages) {
3012 				keg->uk_flags &= ~UMA_ZFLAG_FULL;
3013 				clearfull = 1;
3014 			}
3015 
3016 			/*
3017 			 * We can handle one more allocation. Since we're
3018 			 * clearing ZFLAG_FULL, wake up all procs blocked
3019 			 * on pages. This should be uncommon, so keeping this
3020 			 * simple for now (rather than adding count of blocked
3021 			 * threads etc).
3022 			 */
3023 			wakeup(keg);
3024 		}
3025 	}
3026 	KEG_UNLOCK(keg);
3027 	if (clearfull) {
3028 		ZONE_LOCK(zone);
3029 		zone->uz_flags &= ~UMA_ZFLAG_FULL;
3030 		wakeup(zone);
3031 		ZONE_UNLOCK(zone);
3032 	}
3033 
3034 }
3035 
3036 /*
3037  * Frees a single item to any zone.
3038  *
3039  * Arguments:
3040  *	zone   The zone to free to
3041  *	item   The item we're freeing
3042  *	udata  User supplied data for the dtor
3043  *	skip   Skip dtors and finis
3044  */
3045 static void
3046 zone_free_item(uma_zone_t zone, void *item, void *udata, enum zfreeskip skip)
3047 {
3048 
3049 #ifdef INVARIANTS
3050 	if (skip == SKIP_NONE) {
3051 		if (zone->uz_flags & UMA_ZONE_MALLOC)
3052 			uma_dbg_free(zone, udata, item);
3053 		else
3054 			uma_dbg_free(zone, NULL, item);
3055 	}
3056 #endif
3057 	if (skip < SKIP_DTOR && zone->uz_dtor)
3058 		zone->uz_dtor(item, zone->uz_size, udata);
3059 
3060 	if (skip < SKIP_FINI && zone->uz_fini)
3061 		zone->uz_fini(item, zone->uz_size);
3062 
3063 	atomic_add_long(&zone->uz_frees, 1);
3064 	zone->uz_release(zone->uz_arg, &item, 1);
3065 }
3066 
3067 /* See uma.h */
3068 int
3069 uma_zone_set_max(uma_zone_t zone, int nitems)
3070 {
3071 	uma_keg_t keg;
3072 
3073 	keg = zone_first_keg(zone);
3074 	if (keg == NULL)
3075 		return (0);
3076 	KEG_LOCK(keg);
3077 	keg->uk_maxpages = (nitems / keg->uk_ipers) * keg->uk_ppera;
3078 	if (keg->uk_maxpages * keg->uk_ipers < nitems)
3079 		keg->uk_maxpages += keg->uk_ppera;
3080 	nitems = (keg->uk_maxpages / keg->uk_ppera) * keg->uk_ipers;
3081 	KEG_UNLOCK(keg);
3082 
3083 	return (nitems);
3084 }
3085 
3086 /* See uma.h */
3087 int
3088 uma_zone_get_max(uma_zone_t zone)
3089 {
3090 	int nitems;
3091 	uma_keg_t keg;
3092 
3093 	keg = zone_first_keg(zone);
3094 	if (keg == NULL)
3095 		return (0);
3096 	KEG_LOCK(keg);
3097 	nitems = (keg->uk_maxpages / keg->uk_ppera) * keg->uk_ipers;
3098 	KEG_UNLOCK(keg);
3099 
3100 	return (nitems);
3101 }
3102 
3103 /* See uma.h */
3104 void
3105 uma_zone_set_warning(uma_zone_t zone, const char *warning)
3106 {
3107 
3108 	ZONE_LOCK(zone);
3109 	zone->uz_warning = warning;
3110 	ZONE_UNLOCK(zone);
3111 }
3112 
3113 /* See uma.h */
3114 void
3115 uma_zone_set_maxaction(uma_zone_t zone, uma_maxaction_t maxaction)
3116 {
3117 
3118 	ZONE_LOCK(zone);
3119 	TASK_INIT(&zone->uz_maxaction, 0, (task_fn_t *)maxaction, zone);
3120 	ZONE_UNLOCK(zone);
3121 }
3122 
3123 /* See uma.h */
3124 int
3125 uma_zone_get_cur(uma_zone_t zone)
3126 {
3127 	int64_t nitems;
3128 	u_int i;
3129 
3130 	ZONE_LOCK(zone);
3131 	nitems = zone->uz_allocs - zone->uz_frees;
3132 	CPU_FOREACH(i) {
3133 		/*
3134 		 * See the comment in sysctl_vm_zone_stats() regarding the
3135 		 * safety of accessing the per-cpu caches. With the zone lock
3136 		 * held, it is safe, but can potentially result in stale data.
3137 		 */
3138 		nitems += zone->uz_cpu[i].uc_allocs -
3139 		    zone->uz_cpu[i].uc_frees;
3140 	}
3141 	ZONE_UNLOCK(zone);
3142 
3143 	return (nitems < 0 ? 0 : nitems);
3144 }
3145 
3146 /* See uma.h */
3147 void
3148 uma_zone_set_init(uma_zone_t zone, uma_init uminit)
3149 {
3150 	uma_keg_t keg;
3151 
3152 	keg = zone_first_keg(zone);
3153 	KASSERT(keg != NULL, ("uma_zone_set_init: Invalid zone type"));
3154 	KEG_LOCK(keg);
3155 	KASSERT(keg->uk_pages == 0,
3156 	    ("uma_zone_set_init on non-empty keg"));
3157 	keg->uk_init = uminit;
3158 	KEG_UNLOCK(keg);
3159 }
3160 
3161 /* See uma.h */
3162 void
3163 uma_zone_set_fini(uma_zone_t zone, uma_fini fini)
3164 {
3165 	uma_keg_t keg;
3166 
3167 	keg = zone_first_keg(zone);
3168 	KASSERT(keg != NULL, ("uma_zone_set_fini: Invalid zone type"));
3169 	KEG_LOCK(keg);
3170 	KASSERT(keg->uk_pages == 0,
3171 	    ("uma_zone_set_fini on non-empty keg"));
3172 	keg->uk_fini = fini;
3173 	KEG_UNLOCK(keg);
3174 }
3175 
3176 /* See uma.h */
3177 void
3178 uma_zone_set_zinit(uma_zone_t zone, uma_init zinit)
3179 {
3180 
3181 	ZONE_LOCK(zone);
3182 	KASSERT(zone_first_keg(zone)->uk_pages == 0,
3183 	    ("uma_zone_set_zinit on non-empty keg"));
3184 	zone->uz_init = zinit;
3185 	ZONE_UNLOCK(zone);
3186 }
3187 
3188 /* See uma.h */
3189 void
3190 uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini)
3191 {
3192 
3193 	ZONE_LOCK(zone);
3194 	KASSERT(zone_first_keg(zone)->uk_pages == 0,
3195 	    ("uma_zone_set_zfini on non-empty keg"));
3196 	zone->uz_fini = zfini;
3197 	ZONE_UNLOCK(zone);
3198 }
3199 
3200 /* See uma.h */
3201 /* XXX uk_freef is not actually used with the zone locked */
3202 void
3203 uma_zone_set_freef(uma_zone_t zone, uma_free freef)
3204 {
3205 	uma_keg_t keg;
3206 
3207 	keg = zone_first_keg(zone);
3208 	KASSERT(keg != NULL, ("uma_zone_set_freef: Invalid zone type"));
3209 	KEG_LOCK(keg);
3210 	keg->uk_freef = freef;
3211 	KEG_UNLOCK(keg);
3212 }
3213 
3214 /* See uma.h */
3215 /* XXX uk_allocf is not actually used with the zone locked */
3216 void
3217 uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf)
3218 {
3219 	uma_keg_t keg;
3220 
3221 	keg = zone_first_keg(zone);
3222 	KEG_LOCK(keg);
3223 	keg->uk_allocf = allocf;
3224 	KEG_UNLOCK(keg);
3225 }
3226 
3227 /* See uma.h */
3228 void
3229 uma_zone_reserve(uma_zone_t zone, int items)
3230 {
3231 	uma_keg_t keg;
3232 
3233 	keg = zone_first_keg(zone);
3234 	if (keg == NULL)
3235 		return;
3236 	KEG_LOCK(keg);
3237 	keg->uk_reserve = items;
3238 	KEG_UNLOCK(keg);
3239 
3240 	return;
3241 }
3242 
3243 /* See uma.h */
3244 int
3245 uma_zone_reserve_kva(uma_zone_t zone, int count)
3246 {
3247 	uma_keg_t keg;
3248 	vm_offset_t kva;
3249 	u_int pages;
3250 
3251 	keg = zone_first_keg(zone);
3252 	if (keg == NULL)
3253 		return (0);
3254 	pages = count / keg->uk_ipers;
3255 
3256 	if (pages * keg->uk_ipers < count)
3257 		pages++;
3258 	pages *= keg->uk_ppera;
3259 
3260 #ifdef UMA_MD_SMALL_ALLOC
3261 	if (keg->uk_ppera > 1) {
3262 #else
3263 	if (1) {
3264 #endif
3265 		kva = kva_alloc((vm_size_t)pages * PAGE_SIZE);
3266 		if (kva == 0)
3267 			return (0);
3268 	} else
3269 		kva = 0;
3270 	KEG_LOCK(keg);
3271 	keg->uk_kva = kva;
3272 	keg->uk_offset = 0;
3273 	keg->uk_maxpages = pages;
3274 #ifdef UMA_MD_SMALL_ALLOC
3275 	keg->uk_allocf = (keg->uk_ppera > 1) ? noobj_alloc : uma_small_alloc;
3276 #else
3277 	keg->uk_allocf = noobj_alloc;
3278 #endif
3279 	keg->uk_flags |= UMA_ZONE_NOFREE;
3280 	KEG_UNLOCK(keg);
3281 
3282 	return (1);
3283 }
3284 
3285 /* See uma.h */
3286 void
3287 uma_prealloc(uma_zone_t zone, int items)
3288 {
3289 	uma_domain_t dom;
3290 	uma_slab_t slab;
3291 	uma_keg_t keg;
3292 	int domain, slabs;
3293 
3294 	keg = zone_first_keg(zone);
3295 	if (keg == NULL)
3296 		return;
3297 	KEG_LOCK(keg);
3298 	slabs = items / keg->uk_ipers;
3299 	domain = 0;
3300 	if (slabs * keg->uk_ipers < items)
3301 		slabs++;
3302 	while (slabs > 0) {
3303 		slab = keg_alloc_slab(keg, zone, domain, M_WAITOK);
3304 		if (slab == NULL)
3305 			break;
3306 		MPASS(slab->us_keg == keg);
3307 		dom = &keg->uk_domain[slab->us_domain];
3308 		LIST_INSERT_HEAD(&dom->ud_free_slab, slab, us_link);
3309 		slabs--;
3310 		domain = (domain + 1) % vm_ndomains;
3311 	}
3312 	KEG_UNLOCK(keg);
3313 }
3314 
3315 /* See uma.h */
3316 static void
3317 uma_reclaim_locked(bool kmem_danger)
3318 {
3319 
3320 	CTR0(KTR_UMA, "UMA: vm asked us to release pages!");
3321 	sx_assert(&uma_drain_lock, SA_XLOCKED);
3322 	bucket_enable();
3323 	zone_foreach(zone_drain);
3324 	if (vm_page_count_min() || kmem_danger) {
3325 		cache_drain_safe(NULL);
3326 		zone_foreach(zone_drain);
3327 	}
3328 	/*
3329 	 * Some slabs may have been freed but this zone will be visited early
3330 	 * we visit again so that we can free pages that are empty once other
3331 	 * zones are drained.  We have to do the same for buckets.
3332 	 */
3333 	zone_drain(slabzone);
3334 	bucket_zone_drain();
3335 }
3336 
3337 void
3338 uma_reclaim(void)
3339 {
3340 
3341 	sx_xlock(&uma_drain_lock);
3342 	uma_reclaim_locked(false);
3343 	sx_xunlock(&uma_drain_lock);
3344 }
3345 
3346 static volatile int uma_reclaim_needed;
3347 
3348 void
3349 uma_reclaim_wakeup(void)
3350 {
3351 
3352 	if (atomic_fetchadd_int(&uma_reclaim_needed, 1) == 0)
3353 		wakeup(uma_reclaim);
3354 }
3355 
3356 void
3357 uma_reclaim_worker(void *arg __unused)
3358 {
3359 
3360 	for (;;) {
3361 		sx_xlock(&uma_drain_lock);
3362 		while (atomic_load_int(&uma_reclaim_needed) == 0)
3363 			sx_sleep(uma_reclaim, &uma_drain_lock, PVM, "umarcl",
3364 			    hz);
3365 		sx_xunlock(&uma_drain_lock);
3366 		EVENTHANDLER_INVOKE(vm_lowmem, VM_LOW_KMEM);
3367 		sx_xlock(&uma_drain_lock);
3368 		uma_reclaim_locked(true);
3369 		atomic_store_int(&uma_reclaim_needed, 0);
3370 		sx_xunlock(&uma_drain_lock);
3371 		/* Don't fire more than once per-second. */
3372 		pause("umarclslp", hz);
3373 	}
3374 }
3375 
3376 /* See uma.h */
3377 int
3378 uma_zone_exhausted(uma_zone_t zone)
3379 {
3380 	int full;
3381 
3382 	ZONE_LOCK(zone);
3383 	full = (zone->uz_flags & UMA_ZFLAG_FULL);
3384 	ZONE_UNLOCK(zone);
3385 	return (full);
3386 }
3387 
3388 int
3389 uma_zone_exhausted_nolock(uma_zone_t zone)
3390 {
3391 	return (zone->uz_flags & UMA_ZFLAG_FULL);
3392 }
3393 
3394 void *
3395 uma_large_malloc_domain(vm_size_t size, int domain, int wait)
3396 {
3397 	vm_offset_t addr;
3398 	uma_slab_t slab;
3399 
3400 	slab = zone_alloc_item(slabzone, NULL, domain, wait);
3401 	if (slab == NULL)
3402 		return (NULL);
3403 	if (domain == UMA_ANYDOMAIN)
3404 		addr = kmem_malloc(kernel_arena, size, wait);
3405 	else
3406 		addr = kmem_malloc_domain(domain, size, wait);
3407 	if (addr != 0) {
3408 		vsetslab(addr, slab);
3409 		slab->us_data = (void *)addr;
3410 		slab->us_flags = UMA_SLAB_KERNEL | UMA_SLAB_MALLOC;
3411 		slab->us_size = size;
3412 		slab->us_domain = vm_phys_domidx(PHYS_TO_VM_PAGE(
3413 		    pmap_kextract(addr)));
3414 		uma_total_inc(size);
3415 	} else {
3416 		zone_free_item(slabzone, slab, NULL, SKIP_NONE);
3417 	}
3418 
3419 	return ((void *)addr);
3420 }
3421 
3422 void *
3423 uma_large_malloc(vm_size_t size, int wait)
3424 {
3425 
3426 	return uma_large_malloc_domain(size, UMA_ANYDOMAIN, wait);
3427 }
3428 
3429 void
3430 uma_large_free(uma_slab_t slab)
3431 {
3432 
3433 	KASSERT((slab->us_flags & UMA_SLAB_KERNEL) != 0,
3434 	    ("uma_large_free:  Memory not allocated with uma_large_malloc."));
3435 	kmem_free(kernel_arena, (vm_offset_t)slab->us_data, slab->us_size);
3436 	uma_total_dec(slab->us_size);
3437 	zone_free_item(slabzone, slab, NULL, SKIP_NONE);
3438 }
3439 
3440 static void
3441 uma_zero_item(void *item, uma_zone_t zone)
3442 {
3443 	int i;
3444 
3445 	if (zone->uz_flags & UMA_ZONE_PCPU) {
3446 		CPU_FOREACH(i)
3447 			bzero(zpcpu_get_cpu(item, i), zone->uz_size);
3448 	} else
3449 		bzero(item, zone->uz_size);
3450 }
3451 
3452 unsigned long
3453 uma_limit(void)
3454 {
3455 
3456 	return (uma_kmem_limit);
3457 }
3458 
3459 void
3460 uma_set_limit(unsigned long limit)
3461 {
3462 
3463 	uma_kmem_limit = limit;
3464 }
3465 
3466 unsigned long
3467 uma_size(void)
3468 {
3469 
3470 	return (uma_kmem_total);
3471 }
3472 
3473 long
3474 uma_avail(void)
3475 {
3476 
3477 	return (uma_kmem_limit - uma_kmem_total);
3478 }
3479 
3480 void
3481 uma_print_stats(void)
3482 {
3483 	zone_foreach(uma_print_zone);
3484 }
3485 
3486 static void
3487 slab_print(uma_slab_t slab)
3488 {
3489 	printf("slab: keg %p, data %p, freecount %d\n",
3490 		slab->us_keg, slab->us_data, slab->us_freecount);
3491 }
3492 
3493 static void
3494 cache_print(uma_cache_t cache)
3495 {
3496 	printf("alloc: %p(%d), free: %p(%d)\n",
3497 		cache->uc_allocbucket,
3498 		cache->uc_allocbucket?cache->uc_allocbucket->ub_cnt:0,
3499 		cache->uc_freebucket,
3500 		cache->uc_freebucket?cache->uc_freebucket->ub_cnt:0);
3501 }
3502 
3503 static void
3504 uma_print_keg(uma_keg_t keg)
3505 {
3506 	uma_domain_t dom;
3507 	uma_slab_t slab;
3508 	int i;
3509 
3510 	printf("keg: %s(%p) size %d(%d) flags %#x ipers %d ppera %d "
3511 	    "out %d free %d limit %d\n",
3512 	    keg->uk_name, keg, keg->uk_size, keg->uk_rsize, keg->uk_flags,
3513 	    keg->uk_ipers, keg->uk_ppera,
3514 	    (keg->uk_pages / keg->uk_ppera) * keg->uk_ipers - keg->uk_free,
3515 	    keg->uk_free, (keg->uk_maxpages / keg->uk_ppera) * keg->uk_ipers);
3516 	for (i = 0; i < vm_ndomains; i++) {
3517 		dom = &keg->uk_domain[i];
3518 		printf("Part slabs:\n");
3519 		LIST_FOREACH(slab, &dom->ud_part_slab, us_link)
3520 			slab_print(slab);
3521 		printf("Free slabs:\n");
3522 		LIST_FOREACH(slab, &dom->ud_free_slab, us_link)
3523 			slab_print(slab);
3524 		printf("Full slabs:\n");
3525 		LIST_FOREACH(slab, &dom->ud_full_slab, us_link)
3526 			slab_print(slab);
3527 	}
3528 }
3529 
3530 void
3531 uma_print_zone(uma_zone_t zone)
3532 {
3533 	uma_cache_t cache;
3534 	uma_klink_t kl;
3535 	int i;
3536 
3537 	printf("zone: %s(%p) size %d flags %#x\n",
3538 	    zone->uz_name, zone, zone->uz_size, zone->uz_flags);
3539 	LIST_FOREACH(kl, &zone->uz_kegs, kl_link)
3540 		uma_print_keg(kl->kl_keg);
3541 	CPU_FOREACH(i) {
3542 		cache = &zone->uz_cpu[i];
3543 		printf("CPU %d Cache:\n", i);
3544 		cache_print(cache);
3545 	}
3546 }
3547 
3548 #ifdef DDB
3549 /*
3550  * Generate statistics across both the zone and its per-cpu cache's.  Return
3551  * desired statistics if the pointer is non-NULL for that statistic.
3552  *
3553  * Note: does not update the zone statistics, as it can't safely clear the
3554  * per-CPU cache statistic.
3555  *
3556  * XXXRW: Following the uc_allocbucket and uc_freebucket pointers here isn't
3557  * safe from off-CPU; we should modify the caches to track this information
3558  * directly so that we don't have to.
3559  */
3560 static void
3561 uma_zone_sumstat(uma_zone_t z, int *cachefreep, uint64_t *allocsp,
3562     uint64_t *freesp, uint64_t *sleepsp)
3563 {
3564 	uma_cache_t cache;
3565 	uint64_t allocs, frees, sleeps;
3566 	int cachefree, cpu;
3567 
3568 	allocs = frees = sleeps = 0;
3569 	cachefree = 0;
3570 	CPU_FOREACH(cpu) {
3571 		cache = &z->uz_cpu[cpu];
3572 		if (cache->uc_allocbucket != NULL)
3573 			cachefree += cache->uc_allocbucket->ub_cnt;
3574 		if (cache->uc_freebucket != NULL)
3575 			cachefree += cache->uc_freebucket->ub_cnt;
3576 		allocs += cache->uc_allocs;
3577 		frees += cache->uc_frees;
3578 	}
3579 	allocs += z->uz_allocs;
3580 	frees += z->uz_frees;
3581 	sleeps += z->uz_sleeps;
3582 	if (cachefreep != NULL)
3583 		*cachefreep = cachefree;
3584 	if (allocsp != NULL)
3585 		*allocsp = allocs;
3586 	if (freesp != NULL)
3587 		*freesp = frees;
3588 	if (sleepsp != NULL)
3589 		*sleepsp = sleeps;
3590 }
3591 #endif /* DDB */
3592 
3593 static int
3594 sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS)
3595 {
3596 	uma_keg_t kz;
3597 	uma_zone_t z;
3598 	int count;
3599 
3600 	count = 0;
3601 	rw_rlock(&uma_rwlock);
3602 	LIST_FOREACH(kz, &uma_kegs, uk_link) {
3603 		LIST_FOREACH(z, &kz->uk_zones, uz_link)
3604 			count++;
3605 	}
3606 	rw_runlock(&uma_rwlock);
3607 	return (sysctl_handle_int(oidp, &count, 0, req));
3608 }
3609 
3610 static int
3611 sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS)
3612 {
3613 	struct uma_stream_header ush;
3614 	struct uma_type_header uth;
3615 	struct uma_percpu_stat ups;
3616 	uma_bucket_t bucket;
3617 	uma_zone_domain_t zdom;
3618 	struct sbuf sbuf;
3619 	uma_cache_t cache;
3620 	uma_klink_t kl;
3621 	uma_keg_t kz;
3622 	uma_zone_t z;
3623 	uma_keg_t k;
3624 	int count, error, i;
3625 
3626 	error = sysctl_wire_old_buffer(req, 0);
3627 	if (error != 0)
3628 		return (error);
3629 	sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
3630 	sbuf_clear_flags(&sbuf, SBUF_INCLUDENUL);
3631 
3632 	count = 0;
3633 	rw_rlock(&uma_rwlock);
3634 	LIST_FOREACH(kz, &uma_kegs, uk_link) {
3635 		LIST_FOREACH(z, &kz->uk_zones, uz_link)
3636 			count++;
3637 	}
3638 
3639 	/*
3640 	 * Insert stream header.
3641 	 */
3642 	bzero(&ush, sizeof(ush));
3643 	ush.ush_version = UMA_STREAM_VERSION;
3644 	ush.ush_maxcpus = (mp_maxid + 1);
3645 	ush.ush_count = count;
3646 	(void)sbuf_bcat(&sbuf, &ush, sizeof(ush));
3647 
3648 	LIST_FOREACH(kz, &uma_kegs, uk_link) {
3649 		LIST_FOREACH(z, &kz->uk_zones, uz_link) {
3650 			bzero(&uth, sizeof(uth));
3651 			ZONE_LOCK(z);
3652 			strlcpy(uth.uth_name, z->uz_name, UTH_MAX_NAME);
3653 			uth.uth_align = kz->uk_align;
3654 			uth.uth_size = kz->uk_size;
3655 			uth.uth_rsize = kz->uk_rsize;
3656 			LIST_FOREACH(kl, &z->uz_kegs, kl_link) {
3657 				k = kl->kl_keg;
3658 				uth.uth_maxpages += k->uk_maxpages;
3659 				uth.uth_pages += k->uk_pages;
3660 				uth.uth_keg_free += k->uk_free;
3661 				uth.uth_limit = (k->uk_maxpages / k->uk_ppera)
3662 				    * k->uk_ipers;
3663 			}
3664 
3665 			/*
3666 			 * A zone is secondary is it is not the first entry
3667 			 * on the keg's zone list.
3668 			 */
3669 			if ((z->uz_flags & UMA_ZONE_SECONDARY) &&
3670 			    (LIST_FIRST(&kz->uk_zones) != z))
3671 				uth.uth_zone_flags = UTH_ZONE_SECONDARY;
3672 
3673 			for (i = 0; i < vm_ndomains; i++) {
3674 				zdom = &z->uz_domain[i];
3675 				LIST_FOREACH(bucket, &zdom->uzd_buckets,
3676 				    ub_link)
3677 					uth.uth_zone_free += bucket->ub_cnt;
3678 			}
3679 			uth.uth_allocs = z->uz_allocs;
3680 			uth.uth_frees = z->uz_frees;
3681 			uth.uth_fails = z->uz_fails;
3682 			uth.uth_sleeps = z->uz_sleeps;
3683 			(void)sbuf_bcat(&sbuf, &uth, sizeof(uth));
3684 			/*
3685 			 * While it is not normally safe to access the cache
3686 			 * bucket pointers while not on the CPU that owns the
3687 			 * cache, we only allow the pointers to be exchanged
3688 			 * without the zone lock held, not invalidated, so
3689 			 * accept the possible race associated with bucket
3690 			 * exchange during monitoring.
3691 			 */
3692 			for (i = 0; i < (mp_maxid + 1); i++) {
3693 				bzero(&ups, sizeof(ups));
3694 				if (kz->uk_flags & UMA_ZFLAG_INTERNAL)
3695 					goto skip;
3696 				if (CPU_ABSENT(i))
3697 					goto skip;
3698 				cache = &z->uz_cpu[i];
3699 				if (cache->uc_allocbucket != NULL)
3700 					ups.ups_cache_free +=
3701 					    cache->uc_allocbucket->ub_cnt;
3702 				if (cache->uc_freebucket != NULL)
3703 					ups.ups_cache_free +=
3704 					    cache->uc_freebucket->ub_cnt;
3705 				ups.ups_allocs = cache->uc_allocs;
3706 				ups.ups_frees = cache->uc_frees;
3707 skip:
3708 				(void)sbuf_bcat(&sbuf, &ups, sizeof(ups));
3709 			}
3710 			ZONE_UNLOCK(z);
3711 		}
3712 	}
3713 	rw_runlock(&uma_rwlock);
3714 	error = sbuf_finish(&sbuf);
3715 	sbuf_delete(&sbuf);
3716 	return (error);
3717 }
3718 
3719 int
3720 sysctl_handle_uma_zone_max(SYSCTL_HANDLER_ARGS)
3721 {
3722 	uma_zone_t zone = *(uma_zone_t *)arg1;
3723 	int error, max;
3724 
3725 	max = uma_zone_get_max(zone);
3726 	error = sysctl_handle_int(oidp, &max, 0, req);
3727 	if (error || !req->newptr)
3728 		return (error);
3729 
3730 	uma_zone_set_max(zone, max);
3731 
3732 	return (0);
3733 }
3734 
3735 int
3736 sysctl_handle_uma_zone_cur(SYSCTL_HANDLER_ARGS)
3737 {
3738 	uma_zone_t zone = *(uma_zone_t *)arg1;
3739 	int cur;
3740 
3741 	cur = uma_zone_get_cur(zone);
3742 	return (sysctl_handle_int(oidp, &cur, 0, req));
3743 }
3744 
3745 #ifdef INVARIANTS
3746 static uma_slab_t
3747 uma_dbg_getslab(uma_zone_t zone, void *item)
3748 {
3749 	uma_slab_t slab;
3750 	uma_keg_t keg;
3751 	uint8_t *mem;
3752 
3753 	mem = (uint8_t *)((uintptr_t)item & (~UMA_SLAB_MASK));
3754 	if (zone->uz_flags & UMA_ZONE_VTOSLAB) {
3755 		slab = vtoslab((vm_offset_t)mem);
3756 	} else {
3757 		/*
3758 		 * It is safe to return the slab here even though the
3759 		 * zone is unlocked because the item's allocation state
3760 		 * essentially holds a reference.
3761 		 */
3762 		ZONE_LOCK(zone);
3763 		keg = LIST_FIRST(&zone->uz_kegs)->kl_keg;
3764 		if (keg->uk_flags & UMA_ZONE_HASH)
3765 			slab = hash_sfind(&keg->uk_hash, mem);
3766 		else
3767 			slab = (uma_slab_t)(mem + keg->uk_pgoff);
3768 		ZONE_UNLOCK(zone);
3769 	}
3770 
3771 	return (slab);
3772 }
3773 
3774 /*
3775  * Set up the slab's freei data such that uma_dbg_free can function.
3776  *
3777  */
3778 static void
3779 uma_dbg_alloc(uma_zone_t zone, uma_slab_t slab, void *item)
3780 {
3781 	uma_keg_t keg;
3782 	int freei;
3783 
3784 	if (zone_first_keg(zone) == NULL)
3785 		return;
3786 	if (slab == NULL) {
3787 		slab = uma_dbg_getslab(zone, item);
3788 		if (slab == NULL)
3789 			panic("uma: item %p did not belong to zone %s\n",
3790 			    item, zone->uz_name);
3791 	}
3792 	keg = slab->us_keg;
3793 	freei = ((uintptr_t)item - (uintptr_t)slab->us_data) / keg->uk_rsize;
3794 
3795 	if (BIT_ISSET(SLAB_SETSIZE, freei, &slab->us_debugfree))
3796 		panic("Duplicate alloc of %p from zone %p(%s) slab %p(%d)\n",
3797 		    item, zone, zone->uz_name, slab, freei);
3798 	BIT_SET_ATOMIC(SLAB_SETSIZE, freei, &slab->us_debugfree);
3799 
3800 	return;
3801 }
3802 
3803 /*
3804  * Verifies freed addresses.  Checks for alignment, valid slab membership
3805  * and duplicate frees.
3806  *
3807  */
3808 static void
3809 uma_dbg_free(uma_zone_t zone, uma_slab_t slab, void *item)
3810 {
3811 	uma_keg_t keg;
3812 	int freei;
3813 
3814 	if (zone_first_keg(zone) == NULL)
3815 		return;
3816 	if (slab == NULL) {
3817 		slab = uma_dbg_getslab(zone, item);
3818 		if (slab == NULL)
3819 			panic("uma: Freed item %p did not belong to zone %s\n",
3820 			    item, zone->uz_name);
3821 	}
3822 	keg = slab->us_keg;
3823 	freei = ((uintptr_t)item - (uintptr_t)slab->us_data) / keg->uk_rsize;
3824 
3825 	if (freei >= keg->uk_ipers)
3826 		panic("Invalid free of %p from zone %p(%s) slab %p(%d)\n",
3827 		    item, zone, zone->uz_name, slab, freei);
3828 
3829 	if (((freei * keg->uk_rsize) + slab->us_data) != item)
3830 		panic("Unaligned free of %p from zone %p(%s) slab %p(%d)\n",
3831 		    item, zone, zone->uz_name, slab, freei);
3832 
3833 	if (!BIT_ISSET(SLAB_SETSIZE, freei, &slab->us_debugfree))
3834 		panic("Duplicate free of %p from zone %p(%s) slab %p(%d)\n",
3835 		    item, zone, zone->uz_name, slab, freei);
3836 
3837 	BIT_CLR_ATOMIC(SLAB_SETSIZE, freei, &slab->us_debugfree);
3838 }
3839 #endif /* INVARIANTS */
3840 
3841 #ifdef DDB
3842 DB_SHOW_COMMAND(uma, db_show_uma)
3843 {
3844 	uma_bucket_t bucket;
3845 	uma_keg_t kz;
3846 	uma_zone_t z;
3847 	uma_zone_domain_t zdom;
3848 	uint64_t allocs, frees, sleeps;
3849 	int cachefree, i;
3850 
3851 	db_printf("%18s %8s %8s %8s %12s %8s %8s\n", "Zone", "Size", "Used",
3852 	    "Free", "Requests", "Sleeps", "Bucket");
3853 	LIST_FOREACH(kz, &uma_kegs, uk_link) {
3854 		LIST_FOREACH(z, &kz->uk_zones, uz_link) {
3855 			if (kz->uk_flags & UMA_ZFLAG_INTERNAL) {
3856 				allocs = z->uz_allocs;
3857 				frees = z->uz_frees;
3858 				sleeps = z->uz_sleeps;
3859 				cachefree = 0;
3860 			} else
3861 				uma_zone_sumstat(z, &cachefree, &allocs,
3862 				    &frees, &sleeps);
3863 			if (!((z->uz_flags & UMA_ZONE_SECONDARY) &&
3864 			    (LIST_FIRST(&kz->uk_zones) != z)))
3865 				cachefree += kz->uk_free;
3866 			for (i = 0; i < vm_ndomains; i++) {
3867 				zdom = &z->uz_domain[i];
3868 				LIST_FOREACH(bucket, &zdom->uzd_buckets,
3869 				    ub_link)
3870 					cachefree += bucket->ub_cnt;
3871 			}
3872 			db_printf("%18s %8ju %8jd %8d %12ju %8ju %8u\n",
3873 			    z->uz_name, (uintmax_t)kz->uk_size,
3874 			    (intmax_t)(allocs - frees), cachefree,
3875 			    (uintmax_t)allocs, sleeps, z->uz_count);
3876 			if (db_pager_quit)
3877 				return;
3878 		}
3879 	}
3880 }
3881 
3882 DB_SHOW_COMMAND(umacache, db_show_umacache)
3883 {
3884 	uma_bucket_t bucket;
3885 	uma_zone_t z;
3886 	uma_zone_domain_t zdom;
3887 	uint64_t allocs, frees;
3888 	int cachefree, i;
3889 
3890 	db_printf("%18s %8s %8s %8s %12s %8s\n", "Zone", "Size", "Used", "Free",
3891 	    "Requests", "Bucket");
3892 	LIST_FOREACH(z, &uma_cachezones, uz_link) {
3893 		uma_zone_sumstat(z, &cachefree, &allocs, &frees, NULL);
3894 		for (i = 0; i < vm_ndomains; i++) {
3895 			zdom = &z->uz_domain[i];
3896 			LIST_FOREACH(bucket, &zdom->uzd_buckets, ub_link)
3897 				cachefree += bucket->ub_cnt;
3898 		}
3899 		db_printf("%18s %8ju %8jd %8d %12ju %8u\n",
3900 		    z->uz_name, (uintmax_t)z->uz_size,
3901 		    (intmax_t)(allocs - frees), cachefree,
3902 		    (uintmax_t)allocs, z->uz_count);
3903 		if (db_pager_quit)
3904 			return;
3905 	}
3906 }
3907 #endif	/* DDB */
3908