xref: /freebsd/sys/vm/uma_core.c (revision 57d7e4cc2c6f50edf9b1d54567e03066b8eb42c5)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2002-2019 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/domainset.h>
63 #include <sys/eventhandler.h>
64 #include <sys/kernel.h>
65 #include <sys/types.h>
66 #include <sys/limits.h>
67 #include <sys/queue.h>
68 #include <sys/malloc.h>
69 #include <sys/ktr.h>
70 #include <sys/lock.h>
71 #include <sys/sysctl.h>
72 #include <sys/mutex.h>
73 #include <sys/proc.h>
74 #include <sys/random.h>
75 #include <sys/rwlock.h>
76 #include <sys/sbuf.h>
77 #include <sys/sched.h>
78 #include <sys/sleepqueue.h>
79 #include <sys/smp.h>
80 #include <sys/smr.h>
81 #include <sys/taskqueue.h>
82 #include <sys/vmmeter.h>
83 
84 #include <vm/vm.h>
85 #include <vm/vm_domainset.h>
86 #include <vm/vm_object.h>
87 #include <vm/vm_page.h>
88 #include <vm/vm_pageout.h>
89 #include <vm/vm_param.h>
90 #include <vm/vm_phys.h>
91 #include <vm/vm_pagequeue.h>
92 #include <vm/vm_map.h>
93 #include <vm/vm_kern.h>
94 #include <vm/vm_extern.h>
95 #include <vm/uma.h>
96 #include <vm/uma_int.h>
97 #include <vm/uma_dbg.h>
98 
99 #include <ddb/ddb.h>
100 
101 #ifdef DEBUG_MEMGUARD
102 #include <vm/memguard.h>
103 #endif
104 
105 #include <machine/md_var.h>
106 
107 #ifdef INVARIANTS
108 #define	UMA_ALWAYS_CTORDTOR	1
109 #else
110 #define	UMA_ALWAYS_CTORDTOR	0
111 #endif
112 
113 /*
114  * This is the zone and keg from which all zones are spawned.
115  */
116 static uma_zone_t kegs;
117 static uma_zone_t zones;
118 
119 /*
120  * These are the two zones from which all offpage uma_slab_ts are allocated.
121  *
122  * One zone is for slab headers that can represent a larger number of items,
123  * making the slabs themselves more efficient, and the other zone is for
124  * headers that are smaller and represent fewer items, making the headers more
125  * efficient.
126  */
127 #define	SLABZONE_SIZE(setsize)					\
128     (sizeof(struct uma_hash_slab) + BITSET_SIZE(setsize) * SLAB_BITSETS)
129 #define	SLABZONE0_SETSIZE	(PAGE_SIZE / 16)
130 #define	SLABZONE1_SETSIZE	SLAB_MAX_SETSIZE
131 #define	SLABZONE0_SIZE	SLABZONE_SIZE(SLABZONE0_SETSIZE)
132 #define	SLABZONE1_SIZE	SLABZONE_SIZE(SLABZONE1_SETSIZE)
133 static uma_zone_t slabzones[2];
134 
135 /*
136  * The initial hash tables come out of this zone so they can be allocated
137  * prior to malloc coming up.
138  */
139 static uma_zone_t hashzone;
140 
141 /* The boot-time adjusted value for cache line alignment. */
142 int uma_align_cache = 64 - 1;
143 
144 static MALLOC_DEFINE(M_UMAHASH, "UMAHash", "UMA Hash Buckets");
145 static MALLOC_DEFINE(M_UMA, "UMA", "UMA Misc");
146 
147 /*
148  * Are we allowed to allocate buckets?
149  */
150 static int bucketdisable = 1;
151 
152 /* Linked list of all kegs in the system */
153 static LIST_HEAD(,uma_keg) uma_kegs = LIST_HEAD_INITIALIZER(uma_kegs);
154 
155 /* Linked list of all cache-only zones in the system */
156 static LIST_HEAD(,uma_zone) uma_cachezones =
157     LIST_HEAD_INITIALIZER(uma_cachezones);
158 
159 /* This RW lock protects the keg list */
160 static struct rwlock_padalign __exclusive_cache_line uma_rwlock;
161 
162 /*
163  * First available virual address for boot time allocations.
164  */
165 static vm_offset_t bootstart;
166 static vm_offset_t bootmem;
167 
168 static struct sx uma_reclaim_lock;
169 
170 /*
171  * kmem soft limit, initialized by uma_set_limit().  Ensure that early
172  * allocations don't trigger a wakeup of the reclaim thread.
173  */
174 unsigned long uma_kmem_limit = LONG_MAX;
175 SYSCTL_ULONG(_vm, OID_AUTO, uma_kmem_limit, CTLFLAG_RD, &uma_kmem_limit, 0,
176     "UMA kernel memory soft limit");
177 unsigned long uma_kmem_total;
178 SYSCTL_ULONG(_vm, OID_AUTO, uma_kmem_total, CTLFLAG_RD, &uma_kmem_total, 0,
179     "UMA kernel memory usage");
180 
181 /* Is the VM done starting up? */
182 static enum {
183 	BOOT_COLD,
184 	BOOT_KVA,
185 	BOOT_RUNNING,
186 	BOOT_SHUTDOWN,
187 } booted = BOOT_COLD;
188 
189 /*
190  * This is the handle used to schedule events that need to happen
191  * outside of the allocation fast path.
192  */
193 static struct callout uma_callout;
194 #define	UMA_TIMEOUT	20		/* Seconds for callout interval. */
195 
196 /*
197  * This structure is passed as the zone ctor arg so that I don't have to create
198  * a special allocation function just for zones.
199  */
200 struct uma_zctor_args {
201 	const char *name;
202 	size_t size;
203 	uma_ctor ctor;
204 	uma_dtor dtor;
205 	uma_init uminit;
206 	uma_fini fini;
207 	uma_import import;
208 	uma_release release;
209 	void *arg;
210 	uma_keg_t keg;
211 	int align;
212 	uint32_t flags;
213 };
214 
215 struct uma_kctor_args {
216 	uma_zone_t zone;
217 	size_t size;
218 	uma_init uminit;
219 	uma_fini fini;
220 	int align;
221 	uint32_t flags;
222 };
223 
224 struct uma_bucket_zone {
225 	uma_zone_t	ubz_zone;
226 	char		*ubz_name;
227 	int		ubz_entries;	/* Number of items it can hold. */
228 	int		ubz_maxsize;	/* Maximum allocation size per-item. */
229 };
230 
231 /*
232  * Compute the actual number of bucket entries to pack them in power
233  * of two sizes for more efficient space utilization.
234  */
235 #define	BUCKET_SIZE(n)						\
236     (((sizeof(void *) * (n)) - sizeof(struct uma_bucket)) / sizeof(void *))
237 
238 #define	BUCKET_MAX	BUCKET_SIZE(256)
239 #define	BUCKET_MIN	2
240 
241 struct uma_bucket_zone bucket_zones[] = {
242 	/* Literal bucket sizes. */
243 	{ NULL, "2 Bucket", 2, 4096 },
244 	{ NULL, "4 Bucket", 4, 3072 },
245 	{ NULL, "8 Bucket", 8, 2048 },
246 	{ NULL, "16 Bucket", 16, 1024 },
247 	/* Rounded down power of 2 sizes for efficiency. */
248 	{ NULL, "32 Bucket", BUCKET_SIZE(32), 512 },
249 	{ NULL, "64 Bucket", BUCKET_SIZE(64), 256 },
250 	{ NULL, "128 Bucket", BUCKET_SIZE(128), 128 },
251 	{ NULL, "256 Bucket", BUCKET_SIZE(256), 64 },
252 	{ NULL, NULL, 0}
253 };
254 
255 /*
256  * Flags and enumerations to be passed to internal functions.
257  */
258 enum zfreeskip {
259 	SKIP_NONE =	0,
260 	SKIP_CNT =	0x00000001,
261 	SKIP_DTOR =	0x00010000,
262 	SKIP_FINI =	0x00020000,
263 };
264 
265 /* Prototypes.. */
266 
267 void	uma_startup1(vm_offset_t);
268 void	uma_startup2(void);
269 
270 static void *noobj_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
271 static void *page_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
272 static void *pcpu_page_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
273 static void *startup_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
274 static void *contig_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
275 static void page_free(void *, vm_size_t, uint8_t);
276 static void pcpu_page_free(void *, vm_size_t, uint8_t);
277 static uma_slab_t keg_alloc_slab(uma_keg_t, uma_zone_t, int, int, int);
278 static void cache_drain(uma_zone_t);
279 static void bucket_drain(uma_zone_t, uma_bucket_t);
280 static void bucket_cache_reclaim(uma_zone_t zone, bool);
281 static int keg_ctor(void *, int, void *, int);
282 static void keg_dtor(void *, int, void *);
283 static int zone_ctor(void *, int, void *, int);
284 static void zone_dtor(void *, int, void *);
285 static inline void item_dtor(uma_zone_t zone, void *item, int size,
286     void *udata, enum zfreeskip skip);
287 static int zero_init(void *, int, int);
288 static void zone_foreach(void (*zfunc)(uma_zone_t, void *), void *);
289 static void zone_foreach_unlocked(void (*zfunc)(uma_zone_t, void *), void *);
290 static void zone_timeout(uma_zone_t zone, void *);
291 static int hash_alloc(struct uma_hash *, u_int);
292 static int hash_expand(struct uma_hash *, struct uma_hash *);
293 static void hash_free(struct uma_hash *hash);
294 static void uma_timeout(void *);
295 static void uma_startup3(void);
296 static void uma_shutdown(void);
297 static void *zone_alloc_item(uma_zone_t, void *, int, int);
298 static void zone_free_item(uma_zone_t, void *, void *, enum zfreeskip);
299 static int zone_alloc_limit(uma_zone_t zone, int count, int flags);
300 static void zone_free_limit(uma_zone_t zone, int count);
301 static void bucket_enable(void);
302 static void bucket_init(void);
303 static uma_bucket_t bucket_alloc(uma_zone_t zone, void *, int);
304 static void bucket_free(uma_zone_t zone, uma_bucket_t, void *);
305 static void bucket_zone_drain(void);
306 static uma_bucket_t zone_alloc_bucket(uma_zone_t, void *, int, int);
307 static void *slab_alloc_item(uma_keg_t keg, uma_slab_t slab);
308 static void slab_free_item(uma_zone_t zone, uma_slab_t slab, void *item);
309 static uma_keg_t uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit,
310     uma_fini fini, int align, uint32_t flags);
311 static int zone_import(void *, void **, int, int, int);
312 static void zone_release(void *, void **, int);
313 static bool cache_alloc(uma_zone_t, uma_cache_t, void *, int);
314 static bool cache_free(uma_zone_t, uma_cache_t, void *, void *, int);
315 
316 static int sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS);
317 static int sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS);
318 static int sysctl_handle_uma_zone_allocs(SYSCTL_HANDLER_ARGS);
319 static int sysctl_handle_uma_zone_frees(SYSCTL_HANDLER_ARGS);
320 static int sysctl_handle_uma_zone_flags(SYSCTL_HANDLER_ARGS);
321 static int sysctl_handle_uma_slab_efficiency(SYSCTL_HANDLER_ARGS);
322 static int sysctl_handle_uma_zone_items(SYSCTL_HANDLER_ARGS);
323 
324 static uint64_t uma_zone_get_allocs(uma_zone_t zone);
325 
326 static SYSCTL_NODE(_vm, OID_AUTO, debug, CTLFLAG_RD, 0,
327     "Memory allocation debugging");
328 
329 #ifdef INVARIANTS
330 static uint64_t uma_keg_get_allocs(uma_keg_t zone);
331 static inline struct noslabbits *slab_dbg_bits(uma_slab_t slab, uma_keg_t keg);
332 
333 static bool uma_dbg_kskip(uma_keg_t keg, void *mem);
334 static bool uma_dbg_zskip(uma_zone_t zone, void *mem);
335 static void uma_dbg_free(uma_zone_t zone, uma_slab_t slab, void *item);
336 static void uma_dbg_alloc(uma_zone_t zone, uma_slab_t slab, void *item);
337 
338 static u_int dbg_divisor = 1;
339 SYSCTL_UINT(_vm_debug, OID_AUTO, divisor,
340     CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &dbg_divisor, 0,
341     "Debug & thrash every this item in memory allocator");
342 
343 static counter_u64_t uma_dbg_cnt = EARLY_COUNTER;
344 static counter_u64_t uma_skip_cnt = EARLY_COUNTER;
345 SYSCTL_COUNTER_U64(_vm_debug, OID_AUTO, trashed, CTLFLAG_RD,
346     &uma_dbg_cnt, "memory items debugged");
347 SYSCTL_COUNTER_U64(_vm_debug, OID_AUTO, skipped, CTLFLAG_RD,
348     &uma_skip_cnt, "memory items skipped, not debugged");
349 #endif
350 
351 SYSINIT(uma_startup3, SI_SUB_VM_CONF, SI_ORDER_SECOND, uma_startup3, NULL);
352 
353 SYSCTL_NODE(_vm, OID_AUTO, uma, CTLFLAG_RW, 0, "Universal Memory Allocator");
354 
355 SYSCTL_PROC(_vm, OID_AUTO, zone_count, CTLFLAG_RD|CTLFLAG_MPSAFE|CTLTYPE_INT,
356     0, 0, sysctl_vm_zone_count, "I", "Number of UMA zones");
357 
358 SYSCTL_PROC(_vm, OID_AUTO, zone_stats, CTLFLAG_RD|CTLFLAG_MPSAFE|CTLTYPE_STRUCT,
359     0, 0, sysctl_vm_zone_stats, "s,struct uma_type_header", "Zone Stats");
360 
361 static int zone_warnings = 1;
362 SYSCTL_INT(_vm, OID_AUTO, zone_warnings, CTLFLAG_RWTUN, &zone_warnings, 0,
363     "Warn when UMA zones becomes full");
364 
365 static int multipage_slabs = 1;
366 TUNABLE_INT("vm.debug.uma_multipage_slabs", &multipage_slabs);
367 SYSCTL_INT(_vm_debug, OID_AUTO, uma_multipage_slabs,
368     CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &multipage_slabs, 0,
369     "UMA may choose larger slab sizes for better efficiency");
370 
371 /*
372  * Select the slab zone for an offpage slab with the given maximum item count.
373  */
374 static inline uma_zone_t
375 slabzone(int ipers)
376 {
377 
378 	return (slabzones[ipers > SLABZONE0_SETSIZE]);
379 }
380 
381 /*
382  * This routine checks to see whether or not it's safe to enable buckets.
383  */
384 static void
385 bucket_enable(void)
386 {
387 
388 	KASSERT(booted >= BOOT_KVA, ("Bucket enable before init"));
389 	bucketdisable = vm_page_count_min();
390 }
391 
392 /*
393  * Initialize bucket_zones, the array of zones of buckets of various sizes.
394  *
395  * For each zone, calculate the memory required for each bucket, consisting
396  * of the header and an array of pointers.
397  */
398 static void
399 bucket_init(void)
400 {
401 	struct uma_bucket_zone *ubz;
402 	int size;
403 
404 	for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++) {
405 		size = roundup(sizeof(struct uma_bucket), sizeof(void *));
406 		size += sizeof(void *) * ubz->ubz_entries;
407 		ubz->ubz_zone = uma_zcreate(ubz->ubz_name, size,
408 		    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR,
409 		    UMA_ZONE_MTXCLASS | UMA_ZFLAG_BUCKET |
410 		    UMA_ZONE_FIRSTTOUCH);
411 	}
412 }
413 
414 /*
415  * Given a desired number of entries for a bucket, return the zone from which
416  * to allocate the bucket.
417  */
418 static struct uma_bucket_zone *
419 bucket_zone_lookup(int entries)
420 {
421 	struct uma_bucket_zone *ubz;
422 
423 	for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++)
424 		if (ubz->ubz_entries >= entries)
425 			return (ubz);
426 	ubz--;
427 	return (ubz);
428 }
429 
430 static struct uma_bucket_zone *
431 bucket_zone_max(uma_zone_t zone, int nitems)
432 {
433 	struct uma_bucket_zone *ubz;
434 	int bpcpu;
435 
436 	bpcpu = 2;
437 	if ((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) != 0)
438 		/* Count the cross-domain bucket. */
439 		bpcpu++;
440 
441 	for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++)
442 		if (ubz->ubz_entries * bpcpu * mp_ncpus > nitems)
443 			break;
444 	if (ubz == &bucket_zones[0])
445 		ubz = NULL;
446 	else
447 		ubz--;
448 	return (ubz);
449 }
450 
451 static int
452 bucket_select(int size)
453 {
454 	struct uma_bucket_zone *ubz;
455 
456 	ubz = &bucket_zones[0];
457 	if (size > ubz->ubz_maxsize)
458 		return MAX((ubz->ubz_maxsize * ubz->ubz_entries) / size, 1);
459 
460 	for (; ubz->ubz_entries != 0; ubz++)
461 		if (ubz->ubz_maxsize < size)
462 			break;
463 	ubz--;
464 	return (ubz->ubz_entries);
465 }
466 
467 static uma_bucket_t
468 bucket_alloc(uma_zone_t zone, void *udata, int flags)
469 {
470 	struct uma_bucket_zone *ubz;
471 	uma_bucket_t bucket;
472 
473 	/*
474 	 * Don't allocate buckets early in boot.
475 	 */
476 	if (__predict_false(booted < BOOT_KVA))
477 		return (NULL);
478 
479 	/*
480 	 * To limit bucket recursion we store the original zone flags
481 	 * in a cookie passed via zalloc_arg/zfree_arg.  This allows the
482 	 * NOVM flag to persist even through deep recursions.  We also
483 	 * store ZFLAG_BUCKET once we have recursed attempting to allocate
484 	 * a bucket for a bucket zone so we do not allow infinite bucket
485 	 * recursion.  This cookie will even persist to frees of unused
486 	 * buckets via the allocation path or bucket allocations in the
487 	 * free path.
488 	 */
489 	if ((zone->uz_flags & UMA_ZFLAG_BUCKET) == 0)
490 		udata = (void *)(uintptr_t)zone->uz_flags;
491 	else {
492 		if ((uintptr_t)udata & UMA_ZFLAG_BUCKET)
493 			return (NULL);
494 		udata = (void *)((uintptr_t)udata | UMA_ZFLAG_BUCKET);
495 	}
496 	if (((uintptr_t)udata & UMA_ZONE_VM) != 0)
497 		flags |= M_NOVM;
498 	ubz = bucket_zone_lookup(zone->uz_bucket_size);
499 	if (ubz->ubz_zone == zone && (ubz + 1)->ubz_entries != 0)
500 		ubz++;
501 	bucket = uma_zalloc_arg(ubz->ubz_zone, udata, flags);
502 	if (bucket) {
503 #ifdef INVARIANTS
504 		bzero(bucket->ub_bucket, sizeof(void *) * ubz->ubz_entries);
505 #endif
506 		bucket->ub_cnt = 0;
507 		bucket->ub_entries = ubz->ubz_entries;
508 		bucket->ub_seq = SMR_SEQ_INVALID;
509 		CTR3(KTR_UMA, "bucket_alloc: zone %s(%p) allocated bucket %p",
510 		    zone->uz_name, zone, bucket);
511 	}
512 
513 	return (bucket);
514 }
515 
516 static void
517 bucket_free(uma_zone_t zone, uma_bucket_t bucket, void *udata)
518 {
519 	struct uma_bucket_zone *ubz;
520 
521 	KASSERT(bucket->ub_cnt == 0,
522 	    ("bucket_free: Freeing a non free bucket."));
523 	KASSERT(bucket->ub_seq == SMR_SEQ_INVALID,
524 	    ("bucket_free: Freeing an SMR bucket."));
525 	if ((zone->uz_flags & UMA_ZFLAG_BUCKET) == 0)
526 		udata = (void *)(uintptr_t)zone->uz_flags;
527 	ubz = bucket_zone_lookup(bucket->ub_entries);
528 	uma_zfree_arg(ubz->ubz_zone, bucket, udata);
529 }
530 
531 static void
532 bucket_zone_drain(void)
533 {
534 	struct uma_bucket_zone *ubz;
535 
536 	for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++)
537 		uma_zone_reclaim(ubz->ubz_zone, UMA_RECLAIM_DRAIN);
538 }
539 
540 /*
541  * Attempt to satisfy an allocation by retrieving a full bucket from one of the
542  * zone's caches.  If a bucket is found the zone is not locked on return.
543  */
544 static uma_bucket_t
545 zone_fetch_bucket(uma_zone_t zone, uma_zone_domain_t zdom)
546 {
547 	uma_bucket_t bucket;
548 	int i;
549 	bool dtor = false;
550 
551 	ZONE_LOCK_ASSERT(zone);
552 
553 	if ((bucket = STAILQ_FIRST(&zdom->uzd_buckets)) == NULL)
554 		return (NULL);
555 
556 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0 &&
557 	    bucket->ub_seq != SMR_SEQ_INVALID) {
558 		if (!smr_poll(zone->uz_smr, bucket->ub_seq, false))
559 			return (NULL);
560 		bucket->ub_seq = SMR_SEQ_INVALID;
561 		dtor = (zone->uz_dtor != NULL) | UMA_ALWAYS_CTORDTOR;
562 	}
563 	MPASS(zdom->uzd_nitems >= bucket->ub_cnt);
564 	STAILQ_REMOVE_HEAD(&zdom->uzd_buckets, ub_link);
565 	zdom->uzd_nitems -= bucket->ub_cnt;
566 	if (zdom->uzd_imin > zdom->uzd_nitems)
567 		zdom->uzd_imin = zdom->uzd_nitems;
568 	zone->uz_bkt_count -= bucket->ub_cnt;
569 	ZONE_UNLOCK(zone);
570 	if (dtor)
571 		for (i = 0; i < bucket->ub_cnt; i++)
572 			item_dtor(zone, bucket->ub_bucket[i], zone->uz_size,
573 			    NULL, SKIP_NONE);
574 
575 	return (bucket);
576 }
577 
578 /*
579  * Insert a full bucket into the specified cache.  The "ws" parameter indicates
580  * whether the bucket's contents should be counted as part of the zone's working
581  * set.
582  */
583 static void
584 zone_put_bucket(uma_zone_t zone, uma_zone_domain_t zdom, uma_bucket_t bucket,
585     const bool ws)
586 {
587 
588 	ZONE_LOCK_ASSERT(zone);
589 	KASSERT(!ws || zone->uz_bkt_count < zone->uz_bkt_max,
590 	    ("%s: zone %p overflow", __func__, zone));
591 
592 	STAILQ_INSERT_TAIL(&zdom->uzd_buckets, bucket, ub_link);
593 	zdom->uzd_nitems += bucket->ub_cnt;
594 	if (ws && zdom->uzd_imax < zdom->uzd_nitems)
595 		zdom->uzd_imax = zdom->uzd_nitems;
596 	zone->uz_bkt_count += bucket->ub_cnt;
597 }
598 
599 /* Pops an item out of a per-cpu cache bucket. */
600 static inline void *
601 cache_bucket_pop(uma_cache_t cache, uma_cache_bucket_t bucket)
602 {
603 	void *item;
604 
605 	CRITICAL_ASSERT(curthread);
606 
607 	bucket->ucb_cnt--;
608 	item = bucket->ucb_bucket->ub_bucket[bucket->ucb_cnt];
609 #ifdef INVARIANTS
610 	bucket->ucb_bucket->ub_bucket[bucket->ucb_cnt] = NULL;
611 	KASSERT(item != NULL, ("uma_zalloc: Bucket pointer mangled."));
612 #endif
613 	cache->uc_allocs++;
614 
615 	return (item);
616 }
617 
618 /* Pushes an item into a per-cpu cache bucket. */
619 static inline void
620 cache_bucket_push(uma_cache_t cache, uma_cache_bucket_t bucket, void *item)
621 {
622 
623 	CRITICAL_ASSERT(curthread);
624 	KASSERT(bucket->ucb_bucket->ub_bucket[bucket->ucb_cnt] == NULL,
625 	    ("uma_zfree: Freeing to non free bucket index."));
626 
627 	bucket->ucb_bucket->ub_bucket[bucket->ucb_cnt] = item;
628 	bucket->ucb_cnt++;
629 	cache->uc_frees++;
630 }
631 
632 /*
633  * Unload a UMA bucket from a per-cpu cache.
634  */
635 static inline uma_bucket_t
636 cache_bucket_unload(uma_cache_bucket_t bucket)
637 {
638 	uma_bucket_t b;
639 
640 	b = bucket->ucb_bucket;
641 	if (b != NULL) {
642 		MPASS(b->ub_entries == bucket->ucb_entries);
643 		b->ub_cnt = bucket->ucb_cnt;
644 		bucket->ucb_bucket = NULL;
645 		bucket->ucb_entries = bucket->ucb_cnt = 0;
646 	}
647 
648 	return (b);
649 }
650 
651 static inline uma_bucket_t
652 cache_bucket_unload_alloc(uma_cache_t cache)
653 {
654 
655 	return (cache_bucket_unload(&cache->uc_allocbucket));
656 }
657 
658 static inline uma_bucket_t
659 cache_bucket_unload_free(uma_cache_t cache)
660 {
661 
662 	return (cache_bucket_unload(&cache->uc_freebucket));
663 }
664 
665 static inline uma_bucket_t
666 cache_bucket_unload_cross(uma_cache_t cache)
667 {
668 
669 	return (cache_bucket_unload(&cache->uc_crossbucket));
670 }
671 
672 /*
673  * Load a bucket into a per-cpu cache bucket.
674  */
675 static inline void
676 cache_bucket_load(uma_cache_bucket_t bucket, uma_bucket_t b)
677 {
678 
679 	CRITICAL_ASSERT(curthread);
680 	MPASS(bucket->ucb_bucket == NULL);
681 
682 	bucket->ucb_bucket = b;
683 	bucket->ucb_cnt = b->ub_cnt;
684 	bucket->ucb_entries = b->ub_entries;
685 }
686 
687 static inline void
688 cache_bucket_load_alloc(uma_cache_t cache, uma_bucket_t b)
689 {
690 
691 	cache_bucket_load(&cache->uc_allocbucket, b);
692 }
693 
694 static inline void
695 cache_bucket_load_free(uma_cache_t cache, uma_bucket_t b)
696 {
697 
698 	cache_bucket_load(&cache->uc_freebucket, b);
699 }
700 
701 #ifdef NUMA
702 static inline void
703 cache_bucket_load_cross(uma_cache_t cache, uma_bucket_t b)
704 {
705 
706 	cache_bucket_load(&cache->uc_crossbucket, b);
707 }
708 #endif
709 
710 /*
711  * Copy and preserve ucb_spare.
712  */
713 static inline void
714 cache_bucket_copy(uma_cache_bucket_t b1, uma_cache_bucket_t b2)
715 {
716 
717 	b1->ucb_bucket = b2->ucb_bucket;
718 	b1->ucb_entries = b2->ucb_entries;
719 	b1->ucb_cnt = b2->ucb_cnt;
720 }
721 
722 /*
723  * Swap two cache buckets.
724  */
725 static inline void
726 cache_bucket_swap(uma_cache_bucket_t b1, uma_cache_bucket_t b2)
727 {
728 	struct uma_cache_bucket b3;
729 
730 	CRITICAL_ASSERT(curthread);
731 
732 	cache_bucket_copy(&b3, b1);
733 	cache_bucket_copy(b1, b2);
734 	cache_bucket_copy(b2, &b3);
735 }
736 
737 static void
738 zone_log_warning(uma_zone_t zone)
739 {
740 	static const struct timeval warninterval = { 300, 0 };
741 
742 	if (!zone_warnings || zone->uz_warning == NULL)
743 		return;
744 
745 	if (ratecheck(&zone->uz_ratecheck, &warninterval))
746 		printf("[zone: %s] %s\n", zone->uz_name, zone->uz_warning);
747 }
748 
749 static inline void
750 zone_maxaction(uma_zone_t zone)
751 {
752 
753 	if (zone->uz_maxaction.ta_func != NULL)
754 		taskqueue_enqueue(taskqueue_thread, &zone->uz_maxaction);
755 }
756 
757 /*
758  * Routine called by timeout which is used to fire off some time interval
759  * based calculations.  (stats, hash size, etc.)
760  *
761  * Arguments:
762  *	arg   Unused
763  *
764  * Returns:
765  *	Nothing
766  */
767 static void
768 uma_timeout(void *unused)
769 {
770 	bucket_enable();
771 	zone_foreach(zone_timeout, NULL);
772 
773 	/* Reschedule this event */
774 	callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL);
775 }
776 
777 /*
778  * Update the working set size estimate for the zone's bucket cache.
779  * The constants chosen here are somewhat arbitrary.  With an update period of
780  * 20s (UMA_TIMEOUT), this estimate is dominated by zone activity over the
781  * last 100s.
782  */
783 static void
784 zone_domain_update_wss(uma_zone_domain_t zdom)
785 {
786 	long wss;
787 
788 	MPASS(zdom->uzd_imax >= zdom->uzd_imin);
789 	wss = zdom->uzd_imax - zdom->uzd_imin;
790 	zdom->uzd_imax = zdom->uzd_imin = zdom->uzd_nitems;
791 	zdom->uzd_wss = (4 * wss + zdom->uzd_wss) / 5;
792 }
793 
794 /*
795  * Routine to perform timeout driven calculations.  This expands the
796  * hashes and does per cpu statistics aggregation.
797  *
798  *  Returns nothing.
799  */
800 static void
801 zone_timeout(uma_zone_t zone, void *unused)
802 {
803 	uma_keg_t keg;
804 	u_int slabs, pages;
805 
806 	if ((zone->uz_flags & UMA_ZFLAG_HASH) == 0)
807 		goto update_wss;
808 
809 	keg = zone->uz_keg;
810 
811 	/*
812 	 * Hash zones are non-numa by definition so the first domain
813 	 * is the only one present.
814 	 */
815 	KEG_LOCK(keg, 0);
816 	pages = keg->uk_domain[0].ud_pages;
817 
818 	/*
819 	 * Expand the keg hash table.
820 	 *
821 	 * This is done if the number of slabs is larger than the hash size.
822 	 * What I'm trying to do here is completely reduce collisions.  This
823 	 * may be a little aggressive.  Should I allow for two collisions max?
824 	 */
825 	if ((slabs = pages / keg->uk_ppera) > keg->uk_hash.uh_hashsize) {
826 		struct uma_hash newhash;
827 		struct uma_hash oldhash;
828 		int ret;
829 
830 		/*
831 		 * This is so involved because allocating and freeing
832 		 * while the keg lock is held will lead to deadlock.
833 		 * I have to do everything in stages and check for
834 		 * races.
835 		 */
836 		KEG_UNLOCK(keg, 0);
837 		ret = hash_alloc(&newhash, 1 << fls(slabs));
838 		KEG_LOCK(keg, 0);
839 		if (ret) {
840 			if (hash_expand(&keg->uk_hash, &newhash)) {
841 				oldhash = keg->uk_hash;
842 				keg->uk_hash = newhash;
843 			} else
844 				oldhash = newhash;
845 
846 			KEG_UNLOCK(keg, 0);
847 			hash_free(&oldhash);
848 			goto update_wss;
849 		}
850 	}
851 	KEG_UNLOCK(keg, 0);
852 
853 update_wss:
854 	ZONE_LOCK(zone);
855 	for (int i = 0; i < vm_ndomains; i++)
856 		zone_domain_update_wss(&zone->uz_domain[i]);
857 	ZONE_UNLOCK(zone);
858 }
859 
860 /*
861  * Allocate and zero fill the next sized hash table from the appropriate
862  * backing store.
863  *
864  * Arguments:
865  *	hash  A new hash structure with the old hash size in uh_hashsize
866  *
867  * Returns:
868  *	1 on success and 0 on failure.
869  */
870 static int
871 hash_alloc(struct uma_hash *hash, u_int size)
872 {
873 	size_t alloc;
874 
875 	KASSERT(powerof2(size), ("hash size must be power of 2"));
876 	if (size > UMA_HASH_SIZE_INIT)  {
877 		hash->uh_hashsize = size;
878 		alloc = sizeof(hash->uh_slab_hash[0]) * hash->uh_hashsize;
879 		hash->uh_slab_hash = malloc(alloc, M_UMAHASH, M_NOWAIT);
880 	} else {
881 		alloc = sizeof(hash->uh_slab_hash[0]) * UMA_HASH_SIZE_INIT;
882 		hash->uh_slab_hash = zone_alloc_item(hashzone, NULL,
883 		    UMA_ANYDOMAIN, M_WAITOK);
884 		hash->uh_hashsize = UMA_HASH_SIZE_INIT;
885 	}
886 	if (hash->uh_slab_hash) {
887 		bzero(hash->uh_slab_hash, alloc);
888 		hash->uh_hashmask = hash->uh_hashsize - 1;
889 		return (1);
890 	}
891 
892 	return (0);
893 }
894 
895 /*
896  * Expands the hash table for HASH zones.  This is done from zone_timeout
897  * to reduce collisions.  This must not be done in the regular allocation
898  * path, otherwise, we can recurse on the vm while allocating pages.
899  *
900  * Arguments:
901  *	oldhash  The hash you want to expand
902  *	newhash  The hash structure for the new table
903  *
904  * Returns:
905  *	Nothing
906  *
907  * Discussion:
908  */
909 static int
910 hash_expand(struct uma_hash *oldhash, struct uma_hash *newhash)
911 {
912 	uma_hash_slab_t slab;
913 	u_int hval;
914 	u_int idx;
915 
916 	if (!newhash->uh_slab_hash)
917 		return (0);
918 
919 	if (oldhash->uh_hashsize >= newhash->uh_hashsize)
920 		return (0);
921 
922 	/*
923 	 * I need to investigate hash algorithms for resizing without a
924 	 * full rehash.
925 	 */
926 
927 	for (idx = 0; idx < oldhash->uh_hashsize; idx++)
928 		while (!LIST_EMPTY(&oldhash->uh_slab_hash[idx])) {
929 			slab = LIST_FIRST(&oldhash->uh_slab_hash[idx]);
930 			LIST_REMOVE(slab, uhs_hlink);
931 			hval = UMA_HASH(newhash, slab->uhs_data);
932 			LIST_INSERT_HEAD(&newhash->uh_slab_hash[hval],
933 			    slab, uhs_hlink);
934 		}
935 
936 	return (1);
937 }
938 
939 /*
940  * Free the hash bucket to the appropriate backing store.
941  *
942  * Arguments:
943  *	slab_hash  The hash bucket we're freeing
944  *	hashsize   The number of entries in that hash bucket
945  *
946  * Returns:
947  *	Nothing
948  */
949 static void
950 hash_free(struct uma_hash *hash)
951 {
952 	if (hash->uh_slab_hash == NULL)
953 		return;
954 	if (hash->uh_hashsize == UMA_HASH_SIZE_INIT)
955 		zone_free_item(hashzone, hash->uh_slab_hash, NULL, SKIP_NONE);
956 	else
957 		free(hash->uh_slab_hash, M_UMAHASH);
958 }
959 
960 /*
961  * Frees all outstanding items in a bucket
962  *
963  * Arguments:
964  *	zone   The zone to free to, must be unlocked.
965  *	bucket The free/alloc bucket with items.
966  *
967  * Returns:
968  *	Nothing
969  */
970 
971 static void
972 bucket_drain(uma_zone_t zone, uma_bucket_t bucket)
973 {
974 	int i;
975 
976 	if (bucket == NULL || bucket->ub_cnt == 0)
977 		return;
978 
979 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0 &&
980 	    bucket->ub_seq != SMR_SEQ_INVALID) {
981 		smr_wait(zone->uz_smr, bucket->ub_seq);
982 		for (i = 0; i < bucket->ub_cnt; i++)
983 			item_dtor(zone, bucket->ub_bucket[i],
984 			    zone->uz_size, NULL, SKIP_NONE);
985 		bucket->ub_seq = SMR_SEQ_INVALID;
986 	}
987 	if (zone->uz_fini)
988 		for (i = 0; i < bucket->ub_cnt; i++)
989 			zone->uz_fini(bucket->ub_bucket[i], zone->uz_size);
990 	zone->uz_release(zone->uz_arg, bucket->ub_bucket, bucket->ub_cnt);
991 	if (zone->uz_max_items > 0)
992 		zone_free_limit(zone, bucket->ub_cnt);
993 #ifdef INVARIANTS
994 	bzero(bucket->ub_bucket, sizeof(void *) * bucket->ub_cnt);
995 #endif
996 	bucket->ub_cnt = 0;
997 }
998 
999 /*
1000  * Drains the per cpu caches for a zone.
1001  *
1002  * NOTE: This may only be called while the zone is being torn down, and not
1003  * during normal operation.  This is necessary in order that we do not have
1004  * to migrate CPUs to drain the per-CPU caches.
1005  *
1006  * Arguments:
1007  *	zone     The zone to drain, must be unlocked.
1008  *
1009  * Returns:
1010  *	Nothing
1011  */
1012 static void
1013 cache_drain(uma_zone_t zone)
1014 {
1015 	uma_cache_t cache;
1016 	uma_bucket_t bucket;
1017 	int cpu;
1018 
1019 	/*
1020 	 * XXX: It is safe to not lock the per-CPU caches, because we're
1021 	 * tearing down the zone anyway.  I.e., there will be no further use
1022 	 * of the caches at this point.
1023 	 *
1024 	 * XXX: It would good to be able to assert that the zone is being
1025 	 * torn down to prevent improper use of cache_drain().
1026 	 */
1027 	CPU_FOREACH(cpu) {
1028 		cache = &zone->uz_cpu[cpu];
1029 		bucket = cache_bucket_unload_alloc(cache);
1030 		if (bucket != NULL) {
1031 			bucket_drain(zone, bucket);
1032 			bucket_free(zone, bucket, NULL);
1033 		}
1034 		bucket = cache_bucket_unload_free(cache);
1035 		if (bucket != NULL) {
1036 			bucket_drain(zone, bucket);
1037 			bucket_free(zone, bucket, NULL);
1038 		}
1039 		bucket = cache_bucket_unload_cross(cache);
1040 		if (bucket != NULL) {
1041 			bucket_drain(zone, bucket);
1042 			bucket_free(zone, bucket, NULL);
1043 		}
1044 	}
1045 	bucket_cache_reclaim(zone, true);
1046 }
1047 
1048 static void
1049 cache_shrink(uma_zone_t zone, void *unused)
1050 {
1051 
1052 	if (zone->uz_flags & UMA_ZFLAG_INTERNAL)
1053 		return;
1054 
1055 	ZONE_LOCK(zone);
1056 	zone->uz_bucket_size =
1057 	    (zone->uz_bucket_size_min + zone->uz_bucket_size) / 2;
1058 	ZONE_UNLOCK(zone);
1059 }
1060 
1061 static void
1062 cache_drain_safe_cpu(uma_zone_t zone, void *unused)
1063 {
1064 	uma_cache_t cache;
1065 	uma_bucket_t b1, b2, b3;
1066 	int domain;
1067 
1068 	if (zone->uz_flags & UMA_ZFLAG_INTERNAL)
1069 		return;
1070 
1071 	b1 = b2 = b3 = NULL;
1072 	ZONE_LOCK(zone);
1073 	critical_enter();
1074 	if (zone->uz_flags & UMA_ZONE_FIRSTTOUCH)
1075 		domain = PCPU_GET(domain);
1076 	else
1077 		domain = 0;
1078 	cache = &zone->uz_cpu[curcpu];
1079 	b1 = cache_bucket_unload_alloc(cache);
1080 	if (b1 != NULL && b1->ub_cnt != 0) {
1081 		zone_put_bucket(zone, &zone->uz_domain[domain], b1, false);
1082 		b1 = NULL;
1083 	}
1084 
1085 	/*
1086 	 * Don't flush SMR zone buckets.  This leaves the zone without a
1087 	 * bucket and forces every free to synchronize().
1088 	 */
1089 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0)
1090 		goto out;
1091 	b2 = cache_bucket_unload_free(cache);
1092 	if (b2 != NULL && b2->ub_cnt != 0) {
1093 		zone_put_bucket(zone, &zone->uz_domain[domain], b2, false);
1094 		b2 = NULL;
1095 	}
1096 	b3 = cache_bucket_unload_cross(cache);
1097 
1098 out:
1099 	critical_exit();
1100 	ZONE_UNLOCK(zone);
1101 	if (b1)
1102 		bucket_free(zone, b1, NULL);
1103 	if (b2)
1104 		bucket_free(zone, b2, NULL);
1105 	if (b3) {
1106 		bucket_drain(zone, b3);
1107 		bucket_free(zone, b3, NULL);
1108 	}
1109 }
1110 
1111 /*
1112  * Safely drain per-CPU caches of a zone(s) to alloc bucket.
1113  * This is an expensive call because it needs to bind to all CPUs
1114  * one by one and enter a critical section on each of them in order
1115  * to safely access their cache buckets.
1116  * Zone lock must not be held on call this function.
1117  */
1118 static void
1119 pcpu_cache_drain_safe(uma_zone_t zone)
1120 {
1121 	int cpu;
1122 
1123 	/*
1124 	 * Polite bucket sizes shrinking was not enough, shrink aggressively.
1125 	 */
1126 	if (zone)
1127 		cache_shrink(zone, NULL);
1128 	else
1129 		zone_foreach(cache_shrink, NULL);
1130 
1131 	CPU_FOREACH(cpu) {
1132 		thread_lock(curthread);
1133 		sched_bind(curthread, cpu);
1134 		thread_unlock(curthread);
1135 
1136 		if (zone)
1137 			cache_drain_safe_cpu(zone, NULL);
1138 		else
1139 			zone_foreach(cache_drain_safe_cpu, NULL);
1140 	}
1141 	thread_lock(curthread);
1142 	sched_unbind(curthread);
1143 	thread_unlock(curthread);
1144 }
1145 
1146 /*
1147  * Reclaim cached buckets from a zone.  All buckets are reclaimed if the caller
1148  * requested a drain, otherwise the per-domain caches are trimmed to either
1149  * estimated working set size.
1150  */
1151 static void
1152 bucket_cache_reclaim(uma_zone_t zone, bool drain)
1153 {
1154 	uma_zone_domain_t zdom;
1155 	uma_bucket_t bucket;
1156 	long target, tofree;
1157 	int i;
1158 
1159 	for (i = 0; i < vm_ndomains; i++) {
1160 		/*
1161 		 * The cross bucket is partially filled and not part of
1162 		 * the item count.  Reclaim it individually here.
1163 		 */
1164 		zdom = &zone->uz_domain[i];
1165 		ZONE_CROSS_LOCK(zone);
1166 		bucket = zdom->uzd_cross;
1167 		zdom->uzd_cross = NULL;
1168 		ZONE_CROSS_UNLOCK(zone);
1169 		if (bucket != NULL) {
1170 			bucket_drain(zone, bucket);
1171 			bucket_free(zone, bucket, NULL);
1172 		}
1173 
1174 		/*
1175 		 * Shrink the zone bucket size to ensure that the per-CPU caches
1176 		 * don't grow too large.
1177 		 */
1178 		ZONE_LOCK(zone);
1179 		if (i == 0 && zone->uz_bucket_size > zone->uz_bucket_size_min)
1180 			zone->uz_bucket_size--;
1181 
1182 		/*
1183 		 * If we were asked to drain the zone, we are done only once
1184 		 * this bucket cache is empty.  Otherwise, we reclaim items in
1185 		 * excess of the zone's estimated working set size.  If the
1186 		 * difference nitems - imin is larger than the WSS estimate,
1187 		 * then the estimate will grow at the end of this interval and
1188 		 * we ignore the historical average.
1189 		 */
1190 		target = drain ? 0 : lmax(zdom->uzd_wss, zdom->uzd_nitems -
1191 		    zdom->uzd_imin);
1192 		while (zdom->uzd_nitems > target) {
1193 			bucket = STAILQ_FIRST(&zdom->uzd_buckets);
1194 			if (bucket == NULL)
1195 				break;
1196 			tofree = bucket->ub_cnt;
1197 			STAILQ_REMOVE_HEAD(&zdom->uzd_buckets, ub_link);
1198 			zdom->uzd_nitems -= tofree;
1199 
1200 			/*
1201 			 * Shift the bounds of the current WSS interval to avoid
1202 			 * perturbing the estimate.
1203 			 */
1204 			zdom->uzd_imax -= lmin(zdom->uzd_imax, tofree);
1205 			zdom->uzd_imin -= lmin(zdom->uzd_imin, tofree);
1206 
1207 			ZONE_UNLOCK(zone);
1208 			bucket_drain(zone, bucket);
1209 			bucket_free(zone, bucket, NULL);
1210 			ZONE_LOCK(zone);
1211 		}
1212 		ZONE_UNLOCK(zone);
1213 	}
1214 }
1215 
1216 static void
1217 keg_free_slab(uma_keg_t keg, uma_slab_t slab, int start)
1218 {
1219 	uint8_t *mem;
1220 	int i;
1221 	uint8_t flags;
1222 
1223 	CTR4(KTR_UMA, "keg_free_slab keg %s(%p) slab %p, returning %d bytes",
1224 	    keg->uk_name, keg, slab, PAGE_SIZE * keg->uk_ppera);
1225 
1226 	mem = slab_data(slab, keg);
1227 	flags = slab->us_flags;
1228 	i = start;
1229 	if (keg->uk_fini != NULL) {
1230 		for (i--; i > -1; i--)
1231 #ifdef INVARIANTS
1232 		/*
1233 		 * trash_fini implies that dtor was trash_dtor. trash_fini
1234 		 * would check that memory hasn't been modified since free,
1235 		 * which executed trash_dtor.
1236 		 * That's why we need to run uma_dbg_kskip() check here,
1237 		 * albeit we don't make skip check for other init/fini
1238 		 * invocations.
1239 		 */
1240 		if (!uma_dbg_kskip(keg, slab_item(slab, keg, i)) ||
1241 		    keg->uk_fini != trash_fini)
1242 #endif
1243 			keg->uk_fini(slab_item(slab, keg, i), keg->uk_size);
1244 	}
1245 	if (keg->uk_flags & UMA_ZFLAG_OFFPAGE)
1246 		zone_free_item(slabzone(keg->uk_ipers), slab_tohashslab(slab),
1247 		    NULL, SKIP_NONE);
1248 	keg->uk_freef(mem, PAGE_SIZE * keg->uk_ppera, flags);
1249 	uma_total_dec(PAGE_SIZE * keg->uk_ppera);
1250 }
1251 
1252 /*
1253  * Frees pages from a keg back to the system.  This is done on demand from
1254  * the pageout daemon.
1255  *
1256  * Returns nothing.
1257  */
1258 static void
1259 keg_drain(uma_keg_t keg)
1260 {
1261 	struct slabhead freeslabs;
1262 	uma_domain_t dom;
1263 	uma_slab_t slab, tmp;
1264 	int i, n;
1265 
1266 	if (keg->uk_flags & UMA_ZONE_NOFREE || keg->uk_freef == NULL)
1267 		return;
1268 
1269 	for (i = 0; i < vm_ndomains; i++) {
1270 		CTR4(KTR_UMA, "keg_drain %s(%p) domain %d free items: %u",
1271 		    keg->uk_name, keg, i, dom->ud_free_items);
1272 		dom = &keg->uk_domain[i];
1273 		LIST_INIT(&freeslabs);
1274 
1275 		KEG_LOCK(keg, i);
1276 		if ((keg->uk_flags & UMA_ZFLAG_HASH) != 0) {
1277 			LIST_FOREACH(slab, &dom->ud_free_slab, us_link)
1278 				UMA_HASH_REMOVE(&keg->uk_hash, slab);
1279 		}
1280 		n = dom->ud_free_slabs;
1281 		LIST_SWAP(&freeslabs, &dom->ud_free_slab, uma_slab, us_link);
1282 		dom->ud_free_slabs = 0;
1283 		dom->ud_free_items -= n * keg->uk_ipers;
1284 		dom->ud_pages -= n * keg->uk_ppera;
1285 		KEG_UNLOCK(keg, i);
1286 
1287 		LIST_FOREACH_SAFE(slab, &freeslabs, us_link, tmp)
1288 			keg_free_slab(keg, slab, keg->uk_ipers);
1289 	}
1290 }
1291 
1292 static void
1293 zone_reclaim(uma_zone_t zone, int waitok, bool drain)
1294 {
1295 
1296 	/*
1297 	 * Set draining to interlock with zone_dtor() so we can release our
1298 	 * locks as we go.  Only dtor() should do a WAITOK call since it
1299 	 * is the only call that knows the structure will still be available
1300 	 * when it wakes up.
1301 	 */
1302 	ZONE_LOCK(zone);
1303 	while (zone->uz_flags & UMA_ZFLAG_RECLAIMING) {
1304 		if (waitok == M_NOWAIT)
1305 			goto out;
1306 		msleep(zone, &zone->uz_lock, PVM, "zonedrain", 1);
1307 	}
1308 	zone->uz_flags |= UMA_ZFLAG_RECLAIMING;
1309 	ZONE_UNLOCK(zone);
1310 	bucket_cache_reclaim(zone, drain);
1311 
1312 	/*
1313 	 * The DRAINING flag protects us from being freed while
1314 	 * we're running.  Normally the uma_rwlock would protect us but we
1315 	 * must be able to release and acquire the right lock for each keg.
1316 	 */
1317 	if ((zone->uz_flags & UMA_ZFLAG_CACHE) == 0)
1318 		keg_drain(zone->uz_keg);
1319 	ZONE_LOCK(zone);
1320 	zone->uz_flags &= ~UMA_ZFLAG_RECLAIMING;
1321 	wakeup(zone);
1322 out:
1323 	ZONE_UNLOCK(zone);
1324 }
1325 
1326 static void
1327 zone_drain(uma_zone_t zone, void *unused)
1328 {
1329 
1330 	zone_reclaim(zone, M_NOWAIT, true);
1331 }
1332 
1333 static void
1334 zone_trim(uma_zone_t zone, void *unused)
1335 {
1336 
1337 	zone_reclaim(zone, M_NOWAIT, false);
1338 }
1339 
1340 /*
1341  * Allocate a new slab for a keg and inserts it into the partial slab list.
1342  * The keg should be unlocked on entry.  If the allocation succeeds it will
1343  * be locked on return.
1344  *
1345  * Arguments:
1346  *	flags   Wait flags for the item initialization routine
1347  *	aflags  Wait flags for the slab allocation
1348  *
1349  * Returns:
1350  *	The slab that was allocated or NULL if there is no memory and the
1351  *	caller specified M_NOWAIT.
1352  */
1353 static uma_slab_t
1354 keg_alloc_slab(uma_keg_t keg, uma_zone_t zone, int domain, int flags,
1355     int aflags)
1356 {
1357 	uma_domain_t dom;
1358 	uma_alloc allocf;
1359 	uma_slab_t slab;
1360 	unsigned long size;
1361 	uint8_t *mem;
1362 	uint8_t sflags;
1363 	int i;
1364 
1365 	KASSERT(domain >= 0 && domain < vm_ndomains,
1366 	    ("keg_alloc_slab: domain %d out of range", domain));
1367 
1368 	allocf = keg->uk_allocf;
1369 	slab = NULL;
1370 	mem = NULL;
1371 	if (keg->uk_flags & UMA_ZFLAG_OFFPAGE) {
1372 		uma_hash_slab_t hslab;
1373 		hslab = zone_alloc_item(slabzone(keg->uk_ipers), NULL,
1374 		    domain, aflags);
1375 		if (hslab == NULL)
1376 			goto fail;
1377 		slab = &hslab->uhs_slab;
1378 	}
1379 
1380 	/*
1381 	 * This reproduces the old vm_zone behavior of zero filling pages the
1382 	 * first time they are added to a zone.
1383 	 *
1384 	 * Malloced items are zeroed in uma_zalloc.
1385 	 */
1386 
1387 	if ((keg->uk_flags & UMA_ZONE_MALLOC) == 0)
1388 		aflags |= M_ZERO;
1389 	else
1390 		aflags &= ~M_ZERO;
1391 
1392 	if (keg->uk_flags & UMA_ZONE_NODUMP)
1393 		aflags |= M_NODUMP;
1394 
1395 	/* zone is passed for legacy reasons. */
1396 	size = keg->uk_ppera * PAGE_SIZE;
1397 	mem = allocf(zone, size, domain, &sflags, aflags);
1398 	if (mem == NULL) {
1399 		if (keg->uk_flags & UMA_ZFLAG_OFFPAGE)
1400 			zone_free_item(slabzone(keg->uk_ipers),
1401 			    slab_tohashslab(slab), NULL, SKIP_NONE);
1402 		goto fail;
1403 	}
1404 	uma_total_inc(size);
1405 
1406 	/* For HASH zones all pages go to the same uma_domain. */
1407 	if ((keg->uk_flags & UMA_ZFLAG_HASH) != 0)
1408 		domain = 0;
1409 
1410 	/* Point the slab into the allocated memory */
1411 	if (!(keg->uk_flags & UMA_ZFLAG_OFFPAGE))
1412 		slab = (uma_slab_t )(mem + keg->uk_pgoff);
1413 	else
1414 		slab_tohashslab(slab)->uhs_data = mem;
1415 
1416 	if (keg->uk_flags & UMA_ZFLAG_VTOSLAB)
1417 		for (i = 0; i < keg->uk_ppera; i++)
1418 			vsetzoneslab((vm_offset_t)mem + (i * PAGE_SIZE),
1419 			    zone, slab);
1420 
1421 	slab->us_freecount = keg->uk_ipers;
1422 	slab->us_flags = sflags;
1423 	slab->us_domain = domain;
1424 
1425 	BIT_FILL(keg->uk_ipers, &slab->us_free);
1426 #ifdef INVARIANTS
1427 	BIT_ZERO(keg->uk_ipers, slab_dbg_bits(slab, keg));
1428 #endif
1429 
1430 	if (keg->uk_init != NULL) {
1431 		for (i = 0; i < keg->uk_ipers; i++)
1432 			if (keg->uk_init(slab_item(slab, keg, i),
1433 			    keg->uk_size, flags) != 0)
1434 				break;
1435 		if (i != keg->uk_ipers) {
1436 			keg_free_slab(keg, slab, i);
1437 			goto fail;
1438 		}
1439 	}
1440 	KEG_LOCK(keg, domain);
1441 
1442 	CTR3(KTR_UMA, "keg_alloc_slab: allocated slab %p for %s(%p)",
1443 	    slab, keg->uk_name, keg);
1444 
1445 	if (keg->uk_flags & UMA_ZFLAG_HASH)
1446 		UMA_HASH_INSERT(&keg->uk_hash, slab, mem);
1447 
1448 	/*
1449 	 * If we got a slab here it's safe to mark it partially used
1450 	 * and return.  We assume that the caller is going to remove
1451 	 * at least one item.
1452 	 */
1453 	dom = &keg->uk_domain[domain];
1454 	LIST_INSERT_HEAD(&dom->ud_part_slab, slab, us_link);
1455 	dom->ud_pages += keg->uk_ppera;
1456 	dom->ud_free_items += keg->uk_ipers;
1457 
1458 	return (slab);
1459 
1460 fail:
1461 	return (NULL);
1462 }
1463 
1464 /*
1465  * This function is intended to be used early on in place of page_alloc() so
1466  * that we may use the boot time page cache to satisfy allocations before
1467  * the VM is ready.
1468  */
1469 static void *
1470 startup_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
1471     int wait)
1472 {
1473 	vm_paddr_t pa;
1474 	vm_page_t m;
1475 	void *mem;
1476 	int pages;
1477 	int i;
1478 
1479 	pages = howmany(bytes, PAGE_SIZE);
1480 	KASSERT(pages > 0, ("%s can't reserve 0 pages", __func__));
1481 
1482 	*pflag = UMA_SLAB_BOOT;
1483 	m = vm_page_alloc_contig_domain(NULL, 0, domain,
1484 	    malloc2vm_flags(wait) | VM_ALLOC_NOOBJ | VM_ALLOC_WIRED, pages,
1485 	    (vm_paddr_t)0, ~(vm_paddr_t)0, 1, 0, VM_MEMATTR_DEFAULT);
1486 	if (m == NULL)
1487 		return (NULL);
1488 
1489 	pa = VM_PAGE_TO_PHYS(m);
1490 	for (i = 0; i < pages; i++, pa += PAGE_SIZE) {
1491 #if defined(__aarch64__) || defined(__amd64__) || defined(__mips__) || \
1492     defined(__riscv) || defined(__powerpc64__)
1493 		if ((wait & M_NODUMP) == 0)
1494 			dump_add_page(pa);
1495 #endif
1496 	}
1497 	/* Allocate KVA and indirectly advance bootmem. */
1498 	mem = (void *)pmap_map(&bootmem, m->phys_addr,
1499 	    m->phys_addr + (pages * PAGE_SIZE), VM_PROT_READ | VM_PROT_WRITE);
1500         if ((wait & M_ZERO) != 0)
1501                 bzero(mem, pages * PAGE_SIZE);
1502 
1503         return (mem);
1504 }
1505 
1506 static void
1507 startup_free(void *mem, vm_size_t bytes)
1508 {
1509 	vm_offset_t va;
1510 	vm_page_t m;
1511 
1512 	va = (vm_offset_t)mem;
1513 	m = PHYS_TO_VM_PAGE(pmap_kextract(va));
1514 	pmap_remove(kernel_pmap, va, va + bytes);
1515 	for (; bytes != 0; bytes -= PAGE_SIZE, m++) {
1516 #if defined(__aarch64__) || defined(__amd64__) || defined(__mips__) || \
1517     defined(__riscv) || defined(__powerpc64__)
1518 		dump_drop_page(VM_PAGE_TO_PHYS(m));
1519 #endif
1520 		vm_page_unwire_noq(m);
1521 		vm_page_free(m);
1522 	}
1523 }
1524 
1525 /*
1526  * Allocates a number of pages from the system
1527  *
1528  * Arguments:
1529  *	bytes  The number of bytes requested
1530  *	wait  Shall we wait?
1531  *
1532  * Returns:
1533  *	A pointer to the alloced memory or possibly
1534  *	NULL if M_NOWAIT is set.
1535  */
1536 static void *
1537 page_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
1538     int wait)
1539 {
1540 	void *p;	/* Returned page */
1541 
1542 	*pflag = UMA_SLAB_KERNEL;
1543 	p = (void *)kmem_malloc_domainset(DOMAINSET_FIXED(domain), bytes, wait);
1544 
1545 	return (p);
1546 }
1547 
1548 static void *
1549 pcpu_page_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
1550     int wait)
1551 {
1552 	struct pglist alloctail;
1553 	vm_offset_t addr, zkva;
1554 	int cpu, flags;
1555 	vm_page_t p, p_next;
1556 #ifdef NUMA
1557 	struct pcpu *pc;
1558 #endif
1559 
1560 	MPASS(bytes == (mp_maxid + 1) * PAGE_SIZE);
1561 
1562 	TAILQ_INIT(&alloctail);
1563 	flags = VM_ALLOC_SYSTEM | VM_ALLOC_WIRED | VM_ALLOC_NOOBJ |
1564 	    malloc2vm_flags(wait);
1565 	*pflag = UMA_SLAB_KERNEL;
1566 	for (cpu = 0; cpu <= mp_maxid; cpu++) {
1567 		if (CPU_ABSENT(cpu)) {
1568 			p = vm_page_alloc(NULL, 0, flags);
1569 		} else {
1570 #ifndef NUMA
1571 			p = vm_page_alloc(NULL, 0, flags);
1572 #else
1573 			pc = pcpu_find(cpu);
1574 			if (__predict_false(VM_DOMAIN_EMPTY(pc->pc_domain)))
1575 				p = NULL;
1576 			else
1577 				p = vm_page_alloc_domain(NULL, 0,
1578 				    pc->pc_domain, flags);
1579 			if (__predict_false(p == NULL))
1580 				p = vm_page_alloc(NULL, 0, flags);
1581 #endif
1582 		}
1583 		if (__predict_false(p == NULL))
1584 			goto fail;
1585 		TAILQ_INSERT_TAIL(&alloctail, p, listq);
1586 	}
1587 	if ((addr = kva_alloc(bytes)) == 0)
1588 		goto fail;
1589 	zkva = addr;
1590 	TAILQ_FOREACH(p, &alloctail, listq) {
1591 		pmap_qenter(zkva, &p, 1);
1592 		zkva += PAGE_SIZE;
1593 	}
1594 	return ((void*)addr);
1595 fail:
1596 	TAILQ_FOREACH_SAFE(p, &alloctail, listq, p_next) {
1597 		vm_page_unwire_noq(p);
1598 		vm_page_free(p);
1599 	}
1600 	return (NULL);
1601 }
1602 
1603 /*
1604  * Allocates a number of pages from within an object
1605  *
1606  * Arguments:
1607  *	bytes  The number of bytes requested
1608  *	wait   Shall we wait?
1609  *
1610  * Returns:
1611  *	A pointer to the alloced memory or possibly
1612  *	NULL if M_NOWAIT is set.
1613  */
1614 static void *
1615 noobj_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *flags,
1616     int wait)
1617 {
1618 	TAILQ_HEAD(, vm_page) alloctail;
1619 	u_long npages;
1620 	vm_offset_t retkva, zkva;
1621 	vm_page_t p, p_next;
1622 	uma_keg_t keg;
1623 
1624 	TAILQ_INIT(&alloctail);
1625 	keg = zone->uz_keg;
1626 
1627 	npages = howmany(bytes, PAGE_SIZE);
1628 	while (npages > 0) {
1629 		p = vm_page_alloc_domain(NULL, 0, domain, VM_ALLOC_INTERRUPT |
1630 		    VM_ALLOC_WIRED | VM_ALLOC_NOOBJ |
1631 		    ((wait & M_WAITOK) != 0 ? VM_ALLOC_WAITOK :
1632 		    VM_ALLOC_NOWAIT));
1633 		if (p != NULL) {
1634 			/*
1635 			 * Since the page does not belong to an object, its
1636 			 * listq is unused.
1637 			 */
1638 			TAILQ_INSERT_TAIL(&alloctail, p, listq);
1639 			npages--;
1640 			continue;
1641 		}
1642 		/*
1643 		 * Page allocation failed, free intermediate pages and
1644 		 * exit.
1645 		 */
1646 		TAILQ_FOREACH_SAFE(p, &alloctail, listq, p_next) {
1647 			vm_page_unwire_noq(p);
1648 			vm_page_free(p);
1649 		}
1650 		return (NULL);
1651 	}
1652 	*flags = UMA_SLAB_PRIV;
1653 	zkva = keg->uk_kva +
1654 	    atomic_fetchadd_long(&keg->uk_offset, round_page(bytes));
1655 	retkva = zkva;
1656 	TAILQ_FOREACH(p, &alloctail, listq) {
1657 		pmap_qenter(zkva, &p, 1);
1658 		zkva += PAGE_SIZE;
1659 	}
1660 
1661 	return ((void *)retkva);
1662 }
1663 
1664 /*
1665  * Allocate physically contiguous pages.
1666  */
1667 static void *
1668 contig_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
1669     int wait)
1670 {
1671 
1672 	*pflag = UMA_SLAB_KERNEL;
1673 	return ((void *)kmem_alloc_contig_domainset(DOMAINSET_FIXED(domain),
1674 	    bytes, wait, 0, ~(vm_paddr_t)0, 1, 0, VM_MEMATTR_DEFAULT));
1675 }
1676 
1677 /*
1678  * Frees a number of pages to the system
1679  *
1680  * Arguments:
1681  *	mem   A pointer to the memory to be freed
1682  *	size  The size of the memory being freed
1683  *	flags The original p->us_flags field
1684  *
1685  * Returns:
1686  *	Nothing
1687  */
1688 static void
1689 page_free(void *mem, vm_size_t size, uint8_t flags)
1690 {
1691 
1692 	if ((flags & UMA_SLAB_BOOT) != 0) {
1693 		startup_free(mem, size);
1694 		return;
1695 	}
1696 
1697 	KASSERT((flags & UMA_SLAB_KERNEL) != 0,
1698 	    ("UMA: page_free used with invalid flags %x", flags));
1699 
1700 	kmem_free((vm_offset_t)mem, size);
1701 }
1702 
1703 /*
1704  * Frees pcpu zone allocations
1705  *
1706  * Arguments:
1707  *	mem   A pointer to the memory to be freed
1708  *	size  The size of the memory being freed
1709  *	flags The original p->us_flags field
1710  *
1711  * Returns:
1712  *	Nothing
1713  */
1714 static void
1715 pcpu_page_free(void *mem, vm_size_t size, uint8_t flags)
1716 {
1717 	vm_offset_t sva, curva;
1718 	vm_paddr_t paddr;
1719 	vm_page_t m;
1720 
1721 	MPASS(size == (mp_maxid+1)*PAGE_SIZE);
1722 
1723 	if ((flags & UMA_SLAB_BOOT) != 0) {
1724 		startup_free(mem, size);
1725 		return;
1726 	}
1727 
1728 	sva = (vm_offset_t)mem;
1729 	for (curva = sva; curva < sva + size; curva += PAGE_SIZE) {
1730 		paddr = pmap_kextract(curva);
1731 		m = PHYS_TO_VM_PAGE(paddr);
1732 		vm_page_unwire_noq(m);
1733 		vm_page_free(m);
1734 	}
1735 	pmap_qremove(sva, size >> PAGE_SHIFT);
1736 	kva_free(sva, size);
1737 }
1738 
1739 
1740 /*
1741  * Zero fill initializer
1742  *
1743  * Arguments/Returns follow uma_init specifications
1744  */
1745 static int
1746 zero_init(void *mem, int size, int flags)
1747 {
1748 	bzero(mem, size);
1749 	return (0);
1750 }
1751 
1752 #ifdef INVARIANTS
1753 struct noslabbits *
1754 slab_dbg_bits(uma_slab_t slab, uma_keg_t keg)
1755 {
1756 
1757 	return ((void *)((char *)&slab->us_free + BITSET_SIZE(keg->uk_ipers)));
1758 }
1759 #endif
1760 
1761 /*
1762  * Actual size of embedded struct slab (!OFFPAGE).
1763  */
1764 size_t
1765 slab_sizeof(int nitems)
1766 {
1767 	size_t s;
1768 
1769 	s = sizeof(struct uma_slab) + BITSET_SIZE(nitems) * SLAB_BITSETS;
1770 	return (roundup(s, UMA_ALIGN_PTR + 1));
1771 }
1772 
1773 /*
1774  * Size of memory for embedded slabs (!OFFPAGE).
1775  */
1776 size_t
1777 slab_space(int nitems)
1778 {
1779 	return (UMA_SLAB_SIZE - slab_sizeof(nitems));
1780 }
1781 
1782 #define	UMA_FIXPT_SHIFT	31
1783 #define	UMA_FRAC_FIXPT(n, d)						\
1784 	((uint32_t)(((uint64_t)(n) << UMA_FIXPT_SHIFT) / (d)))
1785 #define	UMA_FIXPT_PCT(f)						\
1786 	((u_int)(((uint64_t)100 * (f)) >> UMA_FIXPT_SHIFT))
1787 #define	UMA_PCT_FIXPT(pct)	UMA_FRAC_FIXPT((pct), 100)
1788 #define	UMA_MIN_EFF	UMA_PCT_FIXPT(100 - UMA_MAX_WASTE)
1789 
1790 /*
1791  * Compute the number of items that will fit in a slab.  If hdr is true, the
1792  * item count may be limited to provide space in the slab for an inline slab
1793  * header.  Otherwise, all slab space will be provided for item storage.
1794  */
1795 static u_int
1796 slab_ipers_hdr(u_int size, u_int rsize, u_int slabsize, bool hdr)
1797 {
1798 	u_int ipers;
1799 	u_int padpi;
1800 
1801 	/* The padding between items is not needed after the last item. */
1802 	padpi = rsize - size;
1803 
1804 	if (hdr) {
1805 		/*
1806 		 * Start with the maximum item count and remove items until
1807 		 * the slab header first alongside the allocatable memory.
1808 		 */
1809 		for (ipers = MIN(SLAB_MAX_SETSIZE,
1810 		    (slabsize + padpi - slab_sizeof(1)) / rsize);
1811 		    ipers > 0 &&
1812 		    ipers * rsize - padpi + slab_sizeof(ipers) > slabsize;
1813 		    ipers--)
1814 			continue;
1815 	} else {
1816 		ipers = MIN((slabsize + padpi) / rsize, SLAB_MAX_SETSIZE);
1817 	}
1818 
1819 	return (ipers);
1820 }
1821 
1822 /*
1823  * Compute the number of items that will fit in a slab for a startup zone.
1824  */
1825 int
1826 slab_ipers(size_t size, int align)
1827 {
1828 	int rsize;
1829 
1830 	rsize = roundup(size, align + 1); /* Assume no CACHESPREAD */
1831 	return (slab_ipers_hdr(size, rsize, UMA_SLAB_SIZE, true));
1832 }
1833 
1834 struct keg_layout_result {
1835 	u_int format;
1836 	u_int slabsize;
1837 	u_int ipers;
1838 	u_int eff;
1839 };
1840 
1841 static void
1842 keg_layout_one(uma_keg_t keg, u_int rsize, u_int slabsize, u_int fmt,
1843     struct keg_layout_result *kl)
1844 {
1845 	u_int total;
1846 
1847 	kl->format = fmt;
1848 	kl->slabsize = slabsize;
1849 
1850 	/* Handle INTERNAL as inline with an extra page. */
1851 	if ((fmt & UMA_ZFLAG_INTERNAL) != 0) {
1852 		kl->format &= ~UMA_ZFLAG_INTERNAL;
1853 		kl->slabsize += PAGE_SIZE;
1854 	}
1855 
1856 	kl->ipers = slab_ipers_hdr(keg->uk_size, rsize, kl->slabsize,
1857 	    (fmt & UMA_ZFLAG_OFFPAGE) == 0);
1858 
1859 	/* Account for memory used by an offpage slab header. */
1860 	total = kl->slabsize;
1861 	if ((fmt & UMA_ZFLAG_OFFPAGE) != 0)
1862 		total += slabzone(kl->ipers)->uz_keg->uk_rsize;
1863 
1864 	kl->eff = UMA_FRAC_FIXPT(kl->ipers * rsize, total);
1865 }
1866 
1867 /*
1868  * Determine the format of a uma keg.  This determines where the slab header
1869  * will be placed (inline or offpage) and calculates ipers, rsize, and ppera.
1870  *
1871  * Arguments
1872  *	keg  The zone we should initialize
1873  *
1874  * Returns
1875  *	Nothing
1876  */
1877 static void
1878 keg_layout(uma_keg_t keg)
1879 {
1880 	struct keg_layout_result kl = {}, kl_tmp;
1881 	u_int fmts[2];
1882 	u_int alignsize;
1883 	u_int nfmt;
1884 	u_int pages;
1885 	u_int rsize;
1886 	u_int slabsize;
1887 	u_int i, j;
1888 
1889 	KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0 ||
1890 	    (keg->uk_size <= UMA_PCPU_ALLOC_SIZE &&
1891 	     (keg->uk_flags & UMA_ZONE_CACHESPREAD) == 0),
1892 	    ("%s: cannot configure for PCPU: keg=%s, size=%u, flags=0x%b",
1893 	     __func__, keg->uk_name, keg->uk_size, keg->uk_flags,
1894 	     PRINT_UMA_ZFLAGS));
1895 	KASSERT((keg->uk_flags & (UMA_ZFLAG_INTERNAL | UMA_ZONE_VM)) == 0 ||
1896 	    (keg->uk_flags & (UMA_ZONE_NOTOUCH | UMA_ZONE_PCPU)) == 0,
1897 	    ("%s: incompatible flags 0x%b", __func__, keg->uk_flags,
1898 	     PRINT_UMA_ZFLAGS));
1899 
1900 	alignsize = keg->uk_align + 1;
1901 
1902 	/*
1903 	 * Calculate the size of each allocation (rsize) according to
1904 	 * alignment.  If the requested size is smaller than we have
1905 	 * allocation bits for we round it up.
1906 	 */
1907 	rsize = MAX(keg->uk_size, UMA_SMALLEST_UNIT);
1908 	rsize = roundup2(rsize, alignsize);
1909 
1910 	if ((keg->uk_flags & UMA_ZONE_CACHESPREAD) != 0) {
1911 		/*
1912 		 * We want one item to start on every align boundary in a page.
1913 		 * To do this we will span pages.  We will also extend the item
1914 		 * by the size of align if it is an even multiple of align.
1915 		 * Otherwise, it would fall on the same boundary every time.
1916 		 */
1917 		if ((rsize & alignsize) == 0)
1918 			rsize += alignsize;
1919 		slabsize = rsize * (PAGE_SIZE / alignsize);
1920 		slabsize = MIN(slabsize, rsize * SLAB_MAX_SETSIZE);
1921 		slabsize = MIN(slabsize, UMA_CACHESPREAD_MAX_SIZE);
1922 		slabsize = round_page(slabsize);
1923 	} else {
1924 		/*
1925 		 * Start with a slab size of as many pages as it takes to
1926 		 * represent a single item.  We will try to fit as many
1927 		 * additional items into the slab as possible.
1928 		 */
1929 		slabsize = round_page(keg->uk_size);
1930 	}
1931 
1932 	/* Build a list of all of the available formats for this keg. */
1933 	nfmt = 0;
1934 
1935 	/* Evaluate an inline slab layout. */
1936 	if ((keg->uk_flags & (UMA_ZONE_NOTOUCH | UMA_ZONE_PCPU)) == 0)
1937 		fmts[nfmt++] = 0;
1938 
1939 	/* TODO: vm_page-embedded slab. */
1940 
1941 	/*
1942 	 * We can't do OFFPAGE if we're internal or if we've been
1943 	 * asked to not go to the VM for buckets.  If we do this we
1944 	 * may end up going to the VM for slabs which we do not want
1945 	 * to do if we're UMA_ZONE_VM, which clearly forbids it.
1946 	 * In those cases, evaluate a pseudo-format called INTERNAL
1947 	 * which has an inline slab header and one extra page to
1948 	 * guarantee that it fits.
1949 	 *
1950 	 * Otherwise, see if using an OFFPAGE slab will improve our
1951 	 * efficiency.
1952 	 */
1953 	if ((keg->uk_flags & (UMA_ZFLAG_INTERNAL | UMA_ZONE_VM)) != 0)
1954 		fmts[nfmt++] = UMA_ZFLAG_INTERNAL;
1955 	else
1956 		fmts[nfmt++] = UMA_ZFLAG_OFFPAGE;
1957 
1958 	/*
1959 	 * Choose a slab size and format which satisfy the minimum efficiency.
1960 	 * Prefer the smallest slab size that meets the constraints.
1961 	 *
1962 	 * Start with a minimum slab size, to accommodate CACHESPREAD.  Then,
1963 	 * for small items (up to PAGE_SIZE), the iteration increment is one
1964 	 * page; and for large items, the increment is one item.
1965 	 */
1966 	i = (slabsize + rsize - keg->uk_size) / MAX(PAGE_SIZE, rsize);
1967 	KASSERT(i >= 1, ("keg %s(%p) flags=0x%b slabsize=%u, rsize=%u, i=%u",
1968 	    keg->uk_name, keg, keg->uk_flags, PRINT_UMA_ZFLAGS, slabsize,
1969 	    rsize, i));
1970 	for ( ; ; i++) {
1971 		slabsize = (rsize <= PAGE_SIZE) ? ptoa(i) :
1972 		    round_page(rsize * (i - 1) + keg->uk_size);
1973 
1974 		for (j = 0; j < nfmt; j++) {
1975 			/* Only if we have no viable format yet. */
1976 			if ((fmts[j] & UMA_ZFLAG_INTERNAL) != 0 &&
1977 			    kl.ipers > 0)
1978 				continue;
1979 
1980 			keg_layout_one(keg, rsize, slabsize, fmts[j], &kl_tmp);
1981 			if (kl_tmp.eff <= kl.eff)
1982 				continue;
1983 
1984 			kl = kl_tmp;
1985 
1986 			CTR6(KTR_UMA, "keg %s layout: format %#x "
1987 			    "(ipers %u * rsize %u) / slabsize %#x = %u%% eff",
1988 			    keg->uk_name, kl.format, kl.ipers, rsize,
1989 			    kl.slabsize, UMA_FIXPT_PCT(kl.eff));
1990 
1991 			/* Stop when we reach the minimum efficiency. */
1992 			if (kl.eff >= UMA_MIN_EFF)
1993 				break;
1994 		}
1995 
1996 		if (kl.eff >= UMA_MIN_EFF || !multipage_slabs ||
1997 		    slabsize >= SLAB_MAX_SETSIZE * rsize ||
1998 		    (keg->uk_flags & (UMA_ZONE_PCPU | UMA_ZONE_CONTIG)) != 0)
1999 			break;
2000 	}
2001 
2002 	pages = atop(kl.slabsize);
2003 	if ((keg->uk_flags & UMA_ZONE_PCPU) != 0)
2004 		pages *= mp_maxid + 1;
2005 
2006 	keg->uk_rsize = rsize;
2007 	keg->uk_ipers = kl.ipers;
2008 	keg->uk_ppera = pages;
2009 	keg->uk_flags |= kl.format;
2010 
2011 	/*
2012 	 * How do we find the slab header if it is offpage or if not all item
2013 	 * start addresses are in the same page?  We could solve the latter
2014 	 * case with vaddr alignment, but we don't.
2015 	 */
2016 	if ((keg->uk_flags & UMA_ZFLAG_OFFPAGE) != 0 ||
2017 	    (keg->uk_ipers - 1) * rsize >= PAGE_SIZE) {
2018 		if ((keg->uk_flags & UMA_ZONE_NOTPAGE) != 0)
2019 			keg->uk_flags |= UMA_ZFLAG_HASH;
2020 		else
2021 			keg->uk_flags |= UMA_ZFLAG_VTOSLAB;
2022 	}
2023 
2024 	CTR6(KTR_UMA, "%s: keg=%s, flags=%#x, rsize=%u, ipers=%u, ppera=%u",
2025 	    __func__, keg->uk_name, keg->uk_flags, rsize, keg->uk_ipers,
2026 	    pages);
2027 	KASSERT(keg->uk_ipers > 0 && keg->uk_ipers <= SLAB_MAX_SETSIZE,
2028 	    ("%s: keg=%s, flags=0x%b, rsize=%u, ipers=%u, ppera=%u", __func__,
2029 	     keg->uk_name, keg->uk_flags, PRINT_UMA_ZFLAGS, rsize,
2030 	     keg->uk_ipers, pages));
2031 }
2032 
2033 /*
2034  * Keg header ctor.  This initializes all fields, locks, etc.  And inserts
2035  * the keg onto the global keg list.
2036  *
2037  * Arguments/Returns follow uma_ctor specifications
2038  *	udata  Actually uma_kctor_args
2039  */
2040 static int
2041 keg_ctor(void *mem, int size, void *udata, int flags)
2042 {
2043 	struct uma_kctor_args *arg = udata;
2044 	uma_keg_t keg = mem;
2045 	uma_zone_t zone;
2046 	int i;
2047 
2048 	bzero(keg, size);
2049 	keg->uk_size = arg->size;
2050 	keg->uk_init = arg->uminit;
2051 	keg->uk_fini = arg->fini;
2052 	keg->uk_align = arg->align;
2053 	keg->uk_reserve = 0;
2054 	keg->uk_flags = arg->flags;
2055 
2056 	/*
2057 	 * We use a global round-robin policy by default.  Zones with
2058 	 * UMA_ZONE_FIRSTTOUCH set will use first-touch instead, in which
2059 	 * case the iterator is never run.
2060 	 */
2061 	keg->uk_dr.dr_policy = DOMAINSET_RR();
2062 	keg->uk_dr.dr_iter = 0;
2063 
2064 	/*
2065 	 * The master zone is passed to us at keg-creation time.
2066 	 */
2067 	zone = arg->zone;
2068 	keg->uk_name = zone->uz_name;
2069 
2070 	if (arg->flags & UMA_ZONE_ZINIT)
2071 		keg->uk_init = zero_init;
2072 
2073 	if (arg->flags & UMA_ZONE_MALLOC)
2074 		keg->uk_flags |= UMA_ZFLAG_VTOSLAB;
2075 
2076 #ifndef SMP
2077 	keg->uk_flags &= ~UMA_ZONE_PCPU;
2078 #endif
2079 
2080 	keg_layout(keg);
2081 
2082 	/*
2083 	 * Use a first-touch NUMA policy for all kegs that pmap_extract()
2084 	 * will work on with the exception of critical VM structures
2085 	 * necessary for paging.
2086 	 *
2087 	 * Zones may override the default by specifying either.
2088 	 */
2089 #ifdef NUMA
2090 	if ((keg->uk_flags &
2091 	    (UMA_ZFLAG_HASH | UMA_ZONE_VM | UMA_ZONE_ROUNDROBIN)) == 0)
2092 		keg->uk_flags |= UMA_ZONE_FIRSTTOUCH;
2093 	else if ((keg->uk_flags & UMA_ZONE_FIRSTTOUCH) == 0)
2094 		keg->uk_flags |= UMA_ZONE_ROUNDROBIN;
2095 #endif
2096 
2097 	/*
2098 	 * If we haven't booted yet we need allocations to go through the
2099 	 * startup cache until the vm is ready.
2100 	 */
2101 #ifdef UMA_MD_SMALL_ALLOC
2102 	if (keg->uk_ppera == 1)
2103 		keg->uk_allocf = uma_small_alloc;
2104 	else
2105 #endif
2106 	if (booted < BOOT_KVA)
2107 		keg->uk_allocf = startup_alloc;
2108 	else if (keg->uk_flags & UMA_ZONE_PCPU)
2109 		keg->uk_allocf = pcpu_page_alloc;
2110 	else if ((keg->uk_flags & UMA_ZONE_CONTIG) != 0 && keg->uk_ppera > 1)
2111 		keg->uk_allocf = contig_alloc;
2112 	else
2113 		keg->uk_allocf = page_alloc;
2114 #ifdef UMA_MD_SMALL_ALLOC
2115 	if (keg->uk_ppera == 1)
2116 		keg->uk_freef = uma_small_free;
2117 	else
2118 #endif
2119 	if (keg->uk_flags & UMA_ZONE_PCPU)
2120 		keg->uk_freef = pcpu_page_free;
2121 	else
2122 		keg->uk_freef = page_free;
2123 
2124 	/*
2125 	 * Initialize keg's locks.
2126 	 */
2127 	for (i = 0; i < vm_ndomains; i++)
2128 		KEG_LOCK_INIT(keg, i, (arg->flags & UMA_ZONE_MTXCLASS));
2129 
2130 	/*
2131 	 * If we're putting the slab header in the actual page we need to
2132 	 * figure out where in each page it goes.  See slab_sizeof
2133 	 * definition.
2134 	 */
2135 	if (!(keg->uk_flags & UMA_ZFLAG_OFFPAGE)) {
2136 		size_t shsize;
2137 
2138 		shsize = slab_sizeof(keg->uk_ipers);
2139 		keg->uk_pgoff = (PAGE_SIZE * keg->uk_ppera) - shsize;
2140 		/*
2141 		 * The only way the following is possible is if with our
2142 		 * UMA_ALIGN_PTR adjustments we are now bigger than
2143 		 * UMA_SLAB_SIZE.  I haven't checked whether this is
2144 		 * mathematically possible for all cases, so we make
2145 		 * sure here anyway.
2146 		 */
2147 		KASSERT(keg->uk_pgoff + shsize <= PAGE_SIZE * keg->uk_ppera,
2148 		    ("zone %s ipers %d rsize %d size %d slab won't fit",
2149 		    zone->uz_name, keg->uk_ipers, keg->uk_rsize, keg->uk_size));
2150 	}
2151 
2152 	if (keg->uk_flags & UMA_ZFLAG_HASH)
2153 		hash_alloc(&keg->uk_hash, 0);
2154 
2155 	CTR3(KTR_UMA, "keg_ctor %p zone %s(%p)", keg, zone->uz_name, zone);
2156 
2157 	LIST_INSERT_HEAD(&keg->uk_zones, zone, uz_link);
2158 
2159 	rw_wlock(&uma_rwlock);
2160 	LIST_INSERT_HEAD(&uma_kegs, keg, uk_link);
2161 	rw_wunlock(&uma_rwlock);
2162 	return (0);
2163 }
2164 
2165 static void
2166 zone_kva_available(uma_zone_t zone, void *unused)
2167 {
2168 	uma_keg_t keg;
2169 
2170 	if ((zone->uz_flags & UMA_ZFLAG_CACHE) != 0)
2171 		return;
2172 	KEG_GET(zone, keg);
2173 
2174 	if (keg->uk_allocf == startup_alloc) {
2175 		/* Switch to the real allocator. */
2176 		if (keg->uk_flags & UMA_ZONE_PCPU)
2177 			keg->uk_allocf = pcpu_page_alloc;
2178 		else if ((keg->uk_flags & UMA_ZONE_CONTIG) != 0 &&
2179 		    keg->uk_ppera > 1)
2180 			keg->uk_allocf = contig_alloc;
2181 		else
2182 			keg->uk_allocf = page_alloc;
2183 	}
2184 }
2185 
2186 static void
2187 zone_alloc_counters(uma_zone_t zone, void *unused)
2188 {
2189 
2190 	zone->uz_allocs = counter_u64_alloc(M_WAITOK);
2191 	zone->uz_frees = counter_u64_alloc(M_WAITOK);
2192 	zone->uz_fails = counter_u64_alloc(M_WAITOK);
2193 }
2194 
2195 static void
2196 zone_alloc_sysctl(uma_zone_t zone, void *unused)
2197 {
2198 	uma_zone_domain_t zdom;
2199 	uma_domain_t dom;
2200 	uma_keg_t keg;
2201 	struct sysctl_oid *oid, *domainoid;
2202 	int domains, i, cnt;
2203 	static const char *nokeg = "cache zone";
2204 	char *c;
2205 
2206 	/*
2207 	 * Make a sysctl safe copy of the zone name by removing
2208 	 * any special characters and handling dups by appending
2209 	 * an index.
2210 	 */
2211 	if (zone->uz_namecnt != 0) {
2212 		/* Count the number of decimal digits and '_' separator. */
2213 		for (i = 1, cnt = zone->uz_namecnt; cnt != 0; i++)
2214 			cnt /= 10;
2215 		zone->uz_ctlname = malloc(strlen(zone->uz_name) + i + 1,
2216 		    M_UMA, M_WAITOK);
2217 		sprintf(zone->uz_ctlname, "%s_%d", zone->uz_name,
2218 		    zone->uz_namecnt);
2219 	} else
2220 		zone->uz_ctlname = strdup(zone->uz_name, M_UMA);
2221 	for (c = zone->uz_ctlname; *c != '\0'; c++)
2222 		if (strchr("./\\ -", *c) != NULL)
2223 			*c = '_';
2224 
2225 	/*
2226 	 * Basic parameters at the root.
2227 	 */
2228 	zone->uz_oid = SYSCTL_ADD_NODE(NULL, SYSCTL_STATIC_CHILDREN(_vm_uma),
2229 	    OID_AUTO, zone->uz_ctlname, CTLFLAG_RD, NULL, "");
2230 	oid = zone->uz_oid;
2231 	SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2232 	    "size", CTLFLAG_RD, &zone->uz_size, 0, "Allocation size");
2233 	SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2234 	    "flags", CTLFLAG_RD | CTLTYPE_STRING | CTLFLAG_MPSAFE,
2235 	    zone, 0, sysctl_handle_uma_zone_flags, "A",
2236 	    "Allocator configuration flags");
2237 	SYSCTL_ADD_U16(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2238 	    "bucket_size", CTLFLAG_RD, &zone->uz_bucket_size, 0,
2239 	    "Desired per-cpu cache size");
2240 	SYSCTL_ADD_U16(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2241 	    "bucket_size_max", CTLFLAG_RD, &zone->uz_bucket_size_max, 0,
2242 	    "Maximum allowed per-cpu cache size");
2243 
2244 	/*
2245 	 * keg if present.
2246 	 */
2247 	if ((zone->uz_flags & UMA_ZFLAG_HASH) == 0)
2248 		domains = vm_ndomains;
2249 	else
2250 		domains = 1;
2251 	oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(zone->uz_oid), OID_AUTO,
2252 	    "keg", CTLFLAG_RD, NULL, "");
2253 	keg = zone->uz_keg;
2254 	if ((zone->uz_flags & UMA_ZFLAG_CACHE) == 0) {
2255 		SYSCTL_ADD_CONST_STRING(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2256 		    "name", CTLFLAG_RD, keg->uk_name, "Keg name");
2257 		SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2258 		    "rsize", CTLFLAG_RD, &keg->uk_rsize, 0,
2259 		    "Real object size with alignment");
2260 		SYSCTL_ADD_U16(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2261 		    "ppera", CTLFLAG_RD, &keg->uk_ppera, 0,
2262 		    "pages per-slab allocation");
2263 		SYSCTL_ADD_U16(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2264 		    "ipers", CTLFLAG_RD, &keg->uk_ipers, 0,
2265 		    "items available per-slab");
2266 		SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2267 		    "align", CTLFLAG_RD, &keg->uk_align, 0,
2268 		    "item alignment mask");
2269 		SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2270 		    "efficiency", CTLFLAG_RD | CTLTYPE_INT | CTLFLAG_MPSAFE,
2271 		    keg, 0, sysctl_handle_uma_slab_efficiency, "I",
2272 		    "Slab utilization (100 - internal fragmentation %)");
2273 		domainoid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(oid),
2274 		    OID_AUTO, "domain", CTLFLAG_RD, NULL, "");
2275 		for (i = 0; i < domains; i++) {
2276 			dom = &keg->uk_domain[i];
2277 			oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(domainoid),
2278 			    OID_AUTO, VM_DOMAIN(i)->vmd_name, CTLFLAG_RD,
2279 			    NULL, "");
2280 			SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2281 			    "pages", CTLFLAG_RD, &dom->ud_pages, 0,
2282 			    "Total pages currently allocated from VM");
2283 			SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2284 			    "free_items", CTLFLAG_RD, &dom->ud_free_items, 0,
2285 			    "items free in the slab layer");
2286 		}
2287 	} else
2288 		SYSCTL_ADD_CONST_STRING(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2289 		    "name", CTLFLAG_RD, nokeg, "Keg name");
2290 
2291 	/*
2292 	 * Information about zone limits.
2293 	 */
2294 	oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(zone->uz_oid), OID_AUTO,
2295 	    "limit", CTLFLAG_RD, NULL, "");
2296 	SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2297 	    "items", CTLFLAG_RD | CTLTYPE_U64 | CTLFLAG_MPSAFE,
2298 	    zone, 0, sysctl_handle_uma_zone_items, "QU",
2299 	    "current number of allocated items if limit is set");
2300 	SYSCTL_ADD_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2301 	    "max_items", CTLFLAG_RD, &zone->uz_max_items, 0,
2302 	    "Maximum number of cached items");
2303 	SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2304 	    "sleepers", CTLFLAG_RD, &zone->uz_sleepers, 0,
2305 	    "Number of threads sleeping at limit");
2306 	SYSCTL_ADD_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2307 	    "sleeps", CTLFLAG_RD, &zone->uz_sleeps, 0,
2308 	    "Total zone limit sleeps");
2309 	SYSCTL_ADD_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2310 	    "bucket_max", CTLFLAG_RD, &zone->uz_bkt_max, 0,
2311 	    "Maximum number of items in the bucket cache");
2312 	SYSCTL_ADD_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2313 	    "bucket_cnt", CTLFLAG_RD, &zone->uz_bkt_count, 0,
2314 	    "Number of items in the bucket cache");
2315 
2316 	/*
2317 	 * Per-domain zone information.
2318 	 */
2319 	domainoid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(zone->uz_oid),
2320 	    OID_AUTO, "domain", CTLFLAG_RD, NULL, "");
2321 	if ((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) == 0)
2322 		domains = 1;
2323 	for (i = 0; i < domains; i++) {
2324 		zdom = &zone->uz_domain[i];
2325 		oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(domainoid),
2326 		    OID_AUTO, VM_DOMAIN(i)->vmd_name, CTLFLAG_RD, NULL, "");
2327 		SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2328 		    "nitems", CTLFLAG_RD, &zdom->uzd_nitems,
2329 		    "number of items in this domain");
2330 		SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2331 		    "imax", CTLFLAG_RD, &zdom->uzd_imax,
2332 		    "maximum item count in this period");
2333 		SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2334 		    "imin", CTLFLAG_RD, &zdom->uzd_imin,
2335 		    "minimum item count in this period");
2336 		SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2337 		    "wss", CTLFLAG_RD, &zdom->uzd_wss,
2338 		    "Working set size");
2339 	}
2340 
2341 	/*
2342 	 * General statistics.
2343 	 */
2344 	oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(zone->uz_oid), OID_AUTO,
2345 	    "stats", CTLFLAG_RD, NULL, "");
2346 	SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2347 	    "current", CTLFLAG_RD | CTLTYPE_INT | CTLFLAG_MPSAFE,
2348 	    zone, 1, sysctl_handle_uma_zone_cur, "I",
2349 	    "Current number of allocated items");
2350 	SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2351 	    "allocs", CTLFLAG_RD | CTLTYPE_U64 | CTLFLAG_MPSAFE,
2352 	    zone, 0, sysctl_handle_uma_zone_allocs, "QU",
2353 	    "Total allocation calls");
2354 	SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2355 	    "frees", CTLFLAG_RD | CTLTYPE_U64 | CTLFLAG_MPSAFE,
2356 	    zone, 0, sysctl_handle_uma_zone_frees, "QU",
2357 	    "Total free calls");
2358 	SYSCTL_ADD_COUNTER_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2359 	    "fails", CTLFLAG_RD, &zone->uz_fails,
2360 	    "Number of allocation failures");
2361 	SYSCTL_ADD_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2362 	    "xdomain", CTLFLAG_RD, &zone->uz_xdomain, 0,
2363 	    "Free calls from the wrong domain");
2364 }
2365 
2366 struct uma_zone_count {
2367 	const char	*name;
2368 	int		count;
2369 };
2370 
2371 static void
2372 zone_count(uma_zone_t zone, void *arg)
2373 {
2374 	struct uma_zone_count *cnt;
2375 
2376 	cnt = arg;
2377 	/*
2378 	 * Some zones are rapidly created with identical names and
2379 	 * destroyed out of order.  This can lead to gaps in the count.
2380 	 * Use one greater than the maximum observed for this name.
2381 	 */
2382 	if (strcmp(zone->uz_name, cnt->name) == 0)
2383 		cnt->count = MAX(cnt->count,
2384 		    zone->uz_namecnt + 1);
2385 }
2386 
2387 static void
2388 zone_update_caches(uma_zone_t zone)
2389 {
2390 	int i;
2391 
2392 	for (i = 0; i <= mp_maxid; i++) {
2393 		cache_set_uz_size(&zone->uz_cpu[i], zone->uz_size);
2394 		cache_set_uz_flags(&zone->uz_cpu[i], zone->uz_flags);
2395 	}
2396 }
2397 
2398 /*
2399  * Zone header ctor.  This initializes all fields, locks, etc.
2400  *
2401  * Arguments/Returns follow uma_ctor specifications
2402  *	udata  Actually uma_zctor_args
2403  */
2404 static int
2405 zone_ctor(void *mem, int size, void *udata, int flags)
2406 {
2407 	struct uma_zone_count cnt;
2408 	struct uma_zctor_args *arg = udata;
2409 	uma_zone_t zone = mem;
2410 	uma_zone_t z;
2411 	uma_keg_t keg;
2412 	int i;
2413 
2414 	bzero(zone, size);
2415 	zone->uz_name = arg->name;
2416 	zone->uz_ctor = arg->ctor;
2417 	zone->uz_dtor = arg->dtor;
2418 	zone->uz_init = NULL;
2419 	zone->uz_fini = NULL;
2420 	zone->uz_sleeps = 0;
2421 	zone->uz_xdomain = 0;
2422 	zone->uz_bucket_size = 0;
2423 	zone->uz_bucket_size_min = 0;
2424 	zone->uz_bucket_size_max = BUCKET_MAX;
2425 	zone->uz_flags = (arg->flags & UMA_ZONE_SMR);
2426 	zone->uz_warning = NULL;
2427 	/* The domain structures follow the cpu structures. */
2428 	zone->uz_domain =
2429 	    (struct uma_zone_domain *)&zone->uz_cpu[mp_maxid + 1];
2430 	zone->uz_bkt_max = ULONG_MAX;
2431 	timevalclear(&zone->uz_ratecheck);
2432 
2433 	/* Count the number of duplicate names. */
2434 	cnt.name = arg->name;
2435 	cnt.count = 0;
2436 	zone_foreach(zone_count, &cnt);
2437 	zone->uz_namecnt = cnt.count;
2438 	ZONE_LOCK_INIT(zone, (arg->flags & UMA_ZONE_MTXCLASS));
2439 	ZONE_CROSS_LOCK_INIT(zone);
2440 
2441 	for (i = 0; i < vm_ndomains; i++)
2442 		STAILQ_INIT(&zone->uz_domain[i].uzd_buckets);
2443 
2444 #ifdef INVARIANTS
2445 	if (arg->uminit == trash_init && arg->fini == trash_fini)
2446 		zone->uz_flags |= UMA_ZFLAG_TRASH | UMA_ZFLAG_CTORDTOR;
2447 #endif
2448 
2449 	/*
2450 	 * This is a pure cache zone, no kegs.
2451 	 */
2452 	if (arg->import) {
2453 		KASSERT((arg->flags & UMA_ZFLAG_CACHE) != 0,
2454 		    ("zone_ctor: Import specified for non-cache zone."));
2455 		zone->uz_flags = arg->flags;
2456 		zone->uz_size = arg->size;
2457 		zone->uz_import = arg->import;
2458 		zone->uz_release = arg->release;
2459 		zone->uz_arg = arg->arg;
2460 		rw_wlock(&uma_rwlock);
2461 		LIST_INSERT_HEAD(&uma_cachezones, zone, uz_link);
2462 		rw_wunlock(&uma_rwlock);
2463 		goto out;
2464 	}
2465 
2466 	/*
2467 	 * Use the regular zone/keg/slab allocator.
2468 	 */
2469 	zone->uz_import = zone_import;
2470 	zone->uz_release = zone_release;
2471 	zone->uz_arg = zone;
2472 	keg = arg->keg;
2473 
2474 	if (arg->flags & UMA_ZONE_SECONDARY) {
2475 		KASSERT((zone->uz_flags & UMA_ZONE_SECONDARY) == 0,
2476 		    ("Secondary zone requested UMA_ZFLAG_INTERNAL"));
2477 		KASSERT(arg->keg != NULL, ("Secondary zone on zero'd keg"));
2478 		zone->uz_init = arg->uminit;
2479 		zone->uz_fini = arg->fini;
2480 		zone->uz_flags |= UMA_ZONE_SECONDARY;
2481 		rw_wlock(&uma_rwlock);
2482 		ZONE_LOCK(zone);
2483 		LIST_FOREACH(z, &keg->uk_zones, uz_link) {
2484 			if (LIST_NEXT(z, uz_link) == NULL) {
2485 				LIST_INSERT_AFTER(z, zone, uz_link);
2486 				break;
2487 			}
2488 		}
2489 		ZONE_UNLOCK(zone);
2490 		rw_wunlock(&uma_rwlock);
2491 	} else if (keg == NULL) {
2492 		if ((keg = uma_kcreate(zone, arg->size, arg->uminit, arg->fini,
2493 		    arg->align, arg->flags)) == NULL)
2494 			return (ENOMEM);
2495 	} else {
2496 		struct uma_kctor_args karg;
2497 		int error;
2498 
2499 		/* We should only be here from uma_startup() */
2500 		karg.size = arg->size;
2501 		karg.uminit = arg->uminit;
2502 		karg.fini = arg->fini;
2503 		karg.align = arg->align;
2504 		karg.flags = (arg->flags & ~UMA_ZONE_SMR);
2505 		karg.zone = zone;
2506 		error = keg_ctor(arg->keg, sizeof(struct uma_keg), &karg,
2507 		    flags);
2508 		if (error)
2509 			return (error);
2510 	}
2511 
2512 	/* Inherit properties from the keg. */
2513 	zone->uz_keg = keg;
2514 	zone->uz_size = keg->uk_size;
2515 	zone->uz_flags |= (keg->uk_flags &
2516 	    (UMA_ZONE_INHERIT | UMA_ZFLAG_INHERIT));
2517 
2518 out:
2519 	if (__predict_true(booted >= BOOT_RUNNING)) {
2520 		zone_alloc_counters(zone, NULL);
2521 		zone_alloc_sysctl(zone, NULL);
2522 	} else {
2523 		zone->uz_allocs = EARLY_COUNTER;
2524 		zone->uz_frees = EARLY_COUNTER;
2525 		zone->uz_fails = EARLY_COUNTER;
2526 	}
2527 
2528 	/* Caller requests a private SMR context. */
2529 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0)
2530 		zone->uz_smr = smr_create(zone->uz_name);
2531 
2532 	KASSERT((arg->flags & (UMA_ZONE_MAXBUCKET | UMA_ZONE_NOBUCKET)) !=
2533 	    (UMA_ZONE_MAXBUCKET | UMA_ZONE_NOBUCKET),
2534 	    ("Invalid zone flag combination"));
2535 	if (arg->flags & UMA_ZFLAG_INTERNAL)
2536 		zone->uz_bucket_size_max = zone->uz_bucket_size = 0;
2537 	if ((arg->flags & UMA_ZONE_MAXBUCKET) != 0)
2538 		zone->uz_bucket_size = BUCKET_MAX;
2539 	else if ((arg->flags & UMA_ZONE_MINBUCKET) != 0)
2540 		zone->uz_bucket_size_max = zone->uz_bucket_size = BUCKET_MIN;
2541 	else if ((arg->flags & UMA_ZONE_NOBUCKET) != 0)
2542 		zone->uz_bucket_size = 0;
2543 	else
2544 		zone->uz_bucket_size = bucket_select(zone->uz_size);
2545 	zone->uz_bucket_size_min = zone->uz_bucket_size;
2546 	if (zone->uz_dtor != NULL || zone->uz_ctor != NULL)
2547 		zone->uz_flags |= UMA_ZFLAG_CTORDTOR;
2548 	zone_update_caches(zone);
2549 
2550 	return (0);
2551 }
2552 
2553 /*
2554  * Keg header dtor.  This frees all data, destroys locks, frees the hash
2555  * table and removes the keg from the global list.
2556  *
2557  * Arguments/Returns follow uma_dtor specifications
2558  *	udata  unused
2559  */
2560 static void
2561 keg_dtor(void *arg, int size, void *udata)
2562 {
2563 	uma_keg_t keg;
2564 	uint32_t free, pages;
2565 	int i;
2566 
2567 	keg = (uma_keg_t)arg;
2568 	free = pages = 0;
2569 	for (i = 0; i < vm_ndomains; i++) {
2570 		free += keg->uk_domain[i].ud_free_items;
2571 		pages += keg->uk_domain[i].ud_pages;
2572 		KEG_LOCK_FINI(keg, i);
2573 	}
2574 	if (pages != 0)
2575 		printf("Freed UMA keg (%s) was not empty (%u items). "
2576 		    " Lost %u pages of memory.\n",
2577 		    keg->uk_name ? keg->uk_name : "",
2578 		    pages / keg->uk_ppera * keg->uk_ipers - free, pages);
2579 
2580 	hash_free(&keg->uk_hash);
2581 }
2582 
2583 /*
2584  * Zone header dtor.
2585  *
2586  * Arguments/Returns follow uma_dtor specifications
2587  *	udata  unused
2588  */
2589 static void
2590 zone_dtor(void *arg, int size, void *udata)
2591 {
2592 	uma_zone_t zone;
2593 	uma_keg_t keg;
2594 
2595 	zone = (uma_zone_t)arg;
2596 
2597 	sysctl_remove_oid(zone->uz_oid, 1, 1);
2598 
2599 	if (!(zone->uz_flags & UMA_ZFLAG_INTERNAL))
2600 		cache_drain(zone);
2601 
2602 	rw_wlock(&uma_rwlock);
2603 	LIST_REMOVE(zone, uz_link);
2604 	rw_wunlock(&uma_rwlock);
2605 	/*
2606 	 * XXX there are some races here where
2607 	 * the zone can be drained but zone lock
2608 	 * released and then refilled before we
2609 	 * remove it... we dont care for now
2610 	 */
2611 	zone_reclaim(zone, M_WAITOK, true);
2612 	/*
2613 	 * We only destroy kegs from non secondary/non cache zones.
2614 	 */
2615 	if ((zone->uz_flags & (UMA_ZONE_SECONDARY | UMA_ZFLAG_CACHE)) == 0) {
2616 		keg = zone->uz_keg;
2617 		rw_wlock(&uma_rwlock);
2618 		LIST_REMOVE(keg, uk_link);
2619 		rw_wunlock(&uma_rwlock);
2620 		zone_free_item(kegs, keg, NULL, SKIP_NONE);
2621 	}
2622 	counter_u64_free(zone->uz_allocs);
2623 	counter_u64_free(zone->uz_frees);
2624 	counter_u64_free(zone->uz_fails);
2625 	free(zone->uz_ctlname, M_UMA);
2626 	ZONE_LOCK_FINI(zone);
2627 	ZONE_CROSS_LOCK_FINI(zone);
2628 }
2629 
2630 static void
2631 zone_foreach_unlocked(void (*zfunc)(uma_zone_t, void *arg), void *arg)
2632 {
2633 	uma_keg_t keg;
2634 	uma_zone_t zone;
2635 
2636 	LIST_FOREACH(keg, &uma_kegs, uk_link) {
2637 		LIST_FOREACH(zone, &keg->uk_zones, uz_link)
2638 			zfunc(zone, arg);
2639 	}
2640 	LIST_FOREACH(zone, &uma_cachezones, uz_link)
2641 		zfunc(zone, arg);
2642 }
2643 
2644 /*
2645  * Traverses every zone in the system and calls a callback
2646  *
2647  * Arguments:
2648  *	zfunc  A pointer to a function which accepts a zone
2649  *		as an argument.
2650  *
2651  * Returns:
2652  *	Nothing
2653  */
2654 static void
2655 zone_foreach(void (*zfunc)(uma_zone_t, void *arg), void *arg)
2656 {
2657 
2658 	rw_rlock(&uma_rwlock);
2659 	zone_foreach_unlocked(zfunc, arg);
2660 	rw_runlock(&uma_rwlock);
2661 }
2662 
2663 /*
2664  * Initialize the kernel memory allocator.  This is done after pages can be
2665  * allocated but before general KVA is available.
2666  */
2667 void
2668 uma_startup1(vm_offset_t virtual_avail)
2669 {
2670 	struct uma_zctor_args args;
2671 	size_t ksize, zsize, size;
2672 	uma_keg_t masterkeg;
2673 	uintptr_t m;
2674 	uint8_t pflag;
2675 
2676 	bootstart = bootmem = virtual_avail;
2677 
2678 	rw_init(&uma_rwlock, "UMA lock");
2679 	sx_init(&uma_reclaim_lock, "umareclaim");
2680 
2681 	ksize = sizeof(struct uma_keg) +
2682 	    (sizeof(struct uma_domain) * vm_ndomains);
2683 	ksize = roundup(ksize, UMA_SUPER_ALIGN);
2684 	zsize = sizeof(struct uma_zone) +
2685 	    (sizeof(struct uma_cache) * (mp_maxid + 1)) +
2686 	    (sizeof(struct uma_zone_domain) * vm_ndomains);
2687 	zsize = roundup(zsize, UMA_SUPER_ALIGN);
2688 
2689 	/* Allocate the zone of zones, zone of kegs, and zone of zones keg. */
2690 	size = (zsize * 2) + ksize;
2691 	m = (uintptr_t)startup_alloc(NULL, size, 0, &pflag, M_NOWAIT | M_ZERO);
2692 	zones = (uma_zone_t)m;
2693 	m += zsize;
2694 	kegs = (uma_zone_t)m;
2695 	m += zsize;
2696 	masterkeg = (uma_keg_t)m;
2697 
2698 	/* "manually" create the initial zone */
2699 	memset(&args, 0, sizeof(args));
2700 	args.name = "UMA Kegs";
2701 	args.size = ksize;
2702 	args.ctor = keg_ctor;
2703 	args.dtor = keg_dtor;
2704 	args.uminit = zero_init;
2705 	args.fini = NULL;
2706 	args.keg = masterkeg;
2707 	args.align = UMA_SUPER_ALIGN - 1;
2708 	args.flags = UMA_ZFLAG_INTERNAL;
2709 	zone_ctor(kegs, zsize, &args, M_WAITOK);
2710 
2711 	args.name = "UMA Zones";
2712 	args.size = zsize;
2713 	args.ctor = zone_ctor;
2714 	args.dtor = zone_dtor;
2715 	args.uminit = zero_init;
2716 	args.fini = NULL;
2717 	args.keg = NULL;
2718 	args.align = UMA_SUPER_ALIGN - 1;
2719 	args.flags = UMA_ZFLAG_INTERNAL;
2720 	zone_ctor(zones, zsize, &args, M_WAITOK);
2721 
2722 	/* Now make zones for slab headers */
2723 	slabzones[0] = uma_zcreate("UMA Slabs 0", SLABZONE0_SIZE,
2724 	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
2725 	slabzones[1] = uma_zcreate("UMA Slabs 1", SLABZONE1_SIZE,
2726 	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
2727 
2728 	hashzone = uma_zcreate("UMA Hash",
2729 	    sizeof(struct slabhead *) * UMA_HASH_SIZE_INIT,
2730 	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
2731 
2732 	bucket_init();
2733 	smr_init();
2734 }
2735 
2736 #ifndef UMA_MD_SMALL_ALLOC
2737 extern void vm_radix_reserve_kva(void);
2738 #endif
2739 
2740 /*
2741  * Advertise the availability of normal kva allocations and switch to
2742  * the default back-end allocator.  Marks the KVA we consumed on startup
2743  * as used in the map.
2744  */
2745 void
2746 uma_startup2(void)
2747 {
2748 
2749 	if (bootstart != bootmem) {
2750 		vm_map_lock(kernel_map);
2751 		(void)vm_map_insert(kernel_map, NULL, 0, bootstart, bootmem,
2752 		    VM_PROT_RW, VM_PROT_RW, MAP_NOFAULT);
2753 		vm_map_unlock(kernel_map);
2754 	}
2755 
2756 #ifndef UMA_MD_SMALL_ALLOC
2757 	/* Set up radix zone to use noobj_alloc. */
2758 	vm_radix_reserve_kva();
2759 #endif
2760 
2761 	booted = BOOT_KVA;
2762 	zone_foreach_unlocked(zone_kva_available, NULL);
2763 	bucket_enable();
2764 }
2765 
2766 /*
2767  * Finish our initialization steps.
2768  */
2769 static void
2770 uma_startup3(void)
2771 {
2772 
2773 #ifdef INVARIANTS
2774 	TUNABLE_INT_FETCH("vm.debug.divisor", &dbg_divisor);
2775 	uma_dbg_cnt = counter_u64_alloc(M_WAITOK);
2776 	uma_skip_cnt = counter_u64_alloc(M_WAITOK);
2777 #endif
2778 	zone_foreach_unlocked(zone_alloc_counters, NULL);
2779 	zone_foreach_unlocked(zone_alloc_sysctl, NULL);
2780 	callout_init(&uma_callout, 1);
2781 	callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL);
2782 	booted = BOOT_RUNNING;
2783 
2784 	EVENTHANDLER_REGISTER(shutdown_post_sync, uma_shutdown, NULL,
2785 	    EVENTHANDLER_PRI_FIRST);
2786 }
2787 
2788 static void
2789 uma_shutdown(void)
2790 {
2791 
2792 	booted = BOOT_SHUTDOWN;
2793 }
2794 
2795 static uma_keg_t
2796 uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit, uma_fini fini,
2797 		int align, uint32_t flags)
2798 {
2799 	struct uma_kctor_args args;
2800 
2801 	args.size = size;
2802 	args.uminit = uminit;
2803 	args.fini = fini;
2804 	args.align = (align == UMA_ALIGN_CACHE) ? uma_align_cache : align;
2805 	args.flags = flags;
2806 	args.zone = zone;
2807 	return (zone_alloc_item(kegs, &args, UMA_ANYDOMAIN, M_WAITOK));
2808 }
2809 
2810 /* Public functions */
2811 /* See uma.h */
2812 void
2813 uma_set_align(int align)
2814 {
2815 
2816 	if (align != UMA_ALIGN_CACHE)
2817 		uma_align_cache = align;
2818 }
2819 
2820 /* See uma.h */
2821 uma_zone_t
2822 uma_zcreate(const char *name, size_t size, uma_ctor ctor, uma_dtor dtor,
2823 		uma_init uminit, uma_fini fini, int align, uint32_t flags)
2824 
2825 {
2826 	struct uma_zctor_args args;
2827 	uma_zone_t res;
2828 
2829 	KASSERT(powerof2(align + 1), ("invalid zone alignment %d for \"%s\"",
2830 	    align, name));
2831 
2832 	/* This stuff is essential for the zone ctor */
2833 	memset(&args, 0, sizeof(args));
2834 	args.name = name;
2835 	args.size = size;
2836 	args.ctor = ctor;
2837 	args.dtor = dtor;
2838 	args.uminit = uminit;
2839 	args.fini = fini;
2840 #ifdef  INVARIANTS
2841 	/*
2842 	 * Inject procedures which check for memory use after free if we are
2843 	 * allowed to scramble the memory while it is not allocated.  This
2844 	 * requires that: UMA is actually able to access the memory, no init
2845 	 * or fini procedures, no dependency on the initial value of the
2846 	 * memory, and no (legitimate) use of the memory after free.  Note,
2847 	 * the ctor and dtor do not need to be empty.
2848 	 */
2849 	if ((!(flags & (UMA_ZONE_ZINIT | UMA_ZONE_NOTOUCH |
2850 	    UMA_ZONE_NOFREE))) && uminit == NULL && fini == NULL) {
2851 		args.uminit = trash_init;
2852 		args.fini = trash_fini;
2853 	}
2854 #endif
2855 	args.align = align;
2856 	args.flags = flags;
2857 	args.keg = NULL;
2858 
2859 	sx_slock(&uma_reclaim_lock);
2860 	res = zone_alloc_item(zones, &args, UMA_ANYDOMAIN, M_WAITOK);
2861 	sx_sunlock(&uma_reclaim_lock);
2862 
2863 	return (res);
2864 }
2865 
2866 /* See uma.h */
2867 uma_zone_t
2868 uma_zsecond_create(char *name, uma_ctor ctor, uma_dtor dtor,
2869 		    uma_init zinit, uma_fini zfini, uma_zone_t master)
2870 {
2871 	struct uma_zctor_args args;
2872 	uma_keg_t keg;
2873 	uma_zone_t res;
2874 
2875 	keg = master->uz_keg;
2876 	memset(&args, 0, sizeof(args));
2877 	args.name = name;
2878 	args.size = keg->uk_size;
2879 	args.ctor = ctor;
2880 	args.dtor = dtor;
2881 	args.uminit = zinit;
2882 	args.fini = zfini;
2883 	args.align = keg->uk_align;
2884 	args.flags = keg->uk_flags | UMA_ZONE_SECONDARY;
2885 	args.keg = keg;
2886 
2887 	sx_slock(&uma_reclaim_lock);
2888 	res = zone_alloc_item(zones, &args, UMA_ANYDOMAIN, M_WAITOK);
2889 	sx_sunlock(&uma_reclaim_lock);
2890 
2891 	return (res);
2892 }
2893 
2894 /* See uma.h */
2895 uma_zone_t
2896 uma_zcache_create(char *name, int size, uma_ctor ctor, uma_dtor dtor,
2897 		    uma_init zinit, uma_fini zfini, uma_import zimport,
2898 		    uma_release zrelease, void *arg, int flags)
2899 {
2900 	struct uma_zctor_args args;
2901 
2902 	memset(&args, 0, sizeof(args));
2903 	args.name = name;
2904 	args.size = size;
2905 	args.ctor = ctor;
2906 	args.dtor = dtor;
2907 	args.uminit = zinit;
2908 	args.fini = zfini;
2909 	args.import = zimport;
2910 	args.release = zrelease;
2911 	args.arg = arg;
2912 	args.align = 0;
2913 	args.flags = flags | UMA_ZFLAG_CACHE;
2914 
2915 	return (zone_alloc_item(zones, &args, UMA_ANYDOMAIN, M_WAITOK));
2916 }
2917 
2918 /* See uma.h */
2919 void
2920 uma_zdestroy(uma_zone_t zone)
2921 {
2922 
2923 	/*
2924 	 * Large slabs are expensive to reclaim, so don't bother doing
2925 	 * unnecessary work if we're shutting down.
2926 	 */
2927 	if (booted == BOOT_SHUTDOWN &&
2928 	    zone->uz_fini == NULL && zone->uz_release == zone_release)
2929 		return;
2930 	sx_slock(&uma_reclaim_lock);
2931 	zone_free_item(zones, zone, NULL, SKIP_NONE);
2932 	sx_sunlock(&uma_reclaim_lock);
2933 }
2934 
2935 void
2936 uma_zwait(uma_zone_t zone)
2937 {
2938 	void *item;
2939 
2940 	item = uma_zalloc_arg(zone, NULL, M_WAITOK);
2941 	uma_zfree(zone, item);
2942 }
2943 
2944 void *
2945 uma_zalloc_pcpu_arg(uma_zone_t zone, void *udata, int flags)
2946 {
2947 	void *item, *pcpu_item;
2948 #ifdef SMP
2949 	int i;
2950 
2951 	MPASS(zone->uz_flags & UMA_ZONE_PCPU);
2952 #endif
2953 	item = uma_zalloc_arg(zone, udata, flags & ~M_ZERO);
2954 	if (item == NULL)
2955 		return (NULL);
2956 	pcpu_item = zpcpu_base_to_offset(item);
2957 	if (flags & M_ZERO) {
2958 #ifdef SMP
2959 		for (i = 0; i <= mp_maxid; i++)
2960 			bzero(zpcpu_get_cpu(pcpu_item, i), zone->uz_size);
2961 #else
2962 		bzero(item, zone->uz_size);
2963 #endif
2964 	}
2965 	return (pcpu_item);
2966 }
2967 
2968 /*
2969  * A stub while both regular and pcpu cases are identical.
2970  */
2971 void
2972 uma_zfree_pcpu_arg(uma_zone_t zone, void *pcpu_item, void *udata)
2973 {
2974 	void *item;
2975 
2976 #ifdef SMP
2977 	MPASS(zone->uz_flags & UMA_ZONE_PCPU);
2978 #endif
2979 	item = zpcpu_offset_to_base(pcpu_item);
2980 	uma_zfree_arg(zone, item, udata);
2981 }
2982 
2983 static inline void *
2984 item_ctor(uma_zone_t zone, int uz_flags, int size, void *udata, int flags,
2985     void *item)
2986 {
2987 #ifdef INVARIANTS
2988 	bool skipdbg;
2989 
2990 	skipdbg = uma_dbg_zskip(zone, item);
2991 	if (!skipdbg && (zone->uz_flags & UMA_ZFLAG_TRASH) != 0 &&
2992 	    zone->uz_ctor != trash_ctor)
2993 		trash_ctor(item, size, udata, flags);
2994 #endif
2995 	/* Check flags before loading ctor pointer. */
2996 	if (__predict_false((uz_flags & UMA_ZFLAG_CTORDTOR) != 0) &&
2997 	    __predict_false(zone->uz_ctor != NULL) &&
2998 	    zone->uz_ctor(item, size, udata, flags) != 0) {
2999 		counter_u64_add(zone->uz_fails, 1);
3000 		zone_free_item(zone, item, udata, SKIP_DTOR | SKIP_CNT);
3001 		return (NULL);
3002 	}
3003 #ifdef INVARIANTS
3004 	if (!skipdbg)
3005 		uma_dbg_alloc(zone, NULL, item);
3006 #endif
3007 	if (flags & M_ZERO)
3008 		bzero(item, size);
3009 
3010 	return (item);
3011 }
3012 
3013 static inline void
3014 item_dtor(uma_zone_t zone, void *item, int size, void *udata,
3015     enum zfreeskip skip)
3016 {
3017 #ifdef INVARIANTS
3018 	bool skipdbg;
3019 
3020 	skipdbg = uma_dbg_zskip(zone, item);
3021 	if (skip == SKIP_NONE && !skipdbg) {
3022 		if ((zone->uz_flags & UMA_ZONE_MALLOC) != 0)
3023 			uma_dbg_free(zone, udata, item);
3024 		else
3025 			uma_dbg_free(zone, NULL, item);
3026 	}
3027 #endif
3028 	if (__predict_true(skip < SKIP_DTOR)) {
3029 		if (zone->uz_dtor != NULL)
3030 			zone->uz_dtor(item, size, udata);
3031 #ifdef INVARIANTS
3032 		if (!skipdbg && (zone->uz_flags & UMA_ZFLAG_TRASH) != 0 &&
3033 		    zone->uz_dtor != trash_dtor)
3034 			trash_dtor(item, size, udata);
3035 #endif
3036 	}
3037 }
3038 
3039 #if defined(INVARIANTS) || defined(DEBUG_MEMGUARD) || defined(WITNESS)
3040 #define	UMA_ZALLOC_DEBUG
3041 static int
3042 uma_zalloc_debug(uma_zone_t zone, void **itemp, void *udata, int flags)
3043 {
3044 	int error;
3045 
3046 	error = 0;
3047 #ifdef WITNESS
3048 	if (flags & M_WAITOK) {
3049 		WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
3050 		    "uma_zalloc_debug: zone \"%s\"", zone->uz_name);
3051 	}
3052 #endif
3053 
3054 #ifdef INVARIANTS
3055 	KASSERT((flags & M_EXEC) == 0,
3056 	    ("uma_zalloc_debug: called with M_EXEC"));
3057 	KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
3058 	    ("uma_zalloc_debug: called within spinlock or critical section"));
3059 	KASSERT((zone->uz_flags & UMA_ZONE_PCPU) == 0 || (flags & M_ZERO) == 0,
3060 	    ("uma_zalloc_debug: allocating from a pcpu zone with M_ZERO"));
3061 #endif
3062 
3063 #ifdef DEBUG_MEMGUARD
3064 	if ((zone->uz_flags & UMA_ZONE_SMR) == 0 && memguard_cmp_zone(zone)) {
3065 		void *item;
3066 		item = memguard_alloc(zone->uz_size, flags);
3067 		if (item != NULL) {
3068 			error = EJUSTRETURN;
3069 			if (zone->uz_init != NULL &&
3070 			    zone->uz_init(item, zone->uz_size, flags) != 0) {
3071 				*itemp = NULL;
3072 				return (error);
3073 			}
3074 			if (zone->uz_ctor != NULL &&
3075 			    zone->uz_ctor(item, zone->uz_size, udata,
3076 			    flags) != 0) {
3077 				counter_u64_add(zone->uz_fails, 1);
3078 			    	zone->uz_fini(item, zone->uz_size);
3079 				*itemp = NULL;
3080 				return (error);
3081 			}
3082 			*itemp = item;
3083 			return (error);
3084 		}
3085 		/* This is unfortunate but should not be fatal. */
3086 	}
3087 #endif
3088 	return (error);
3089 }
3090 
3091 static int
3092 uma_zfree_debug(uma_zone_t zone, void *item, void *udata)
3093 {
3094 	KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
3095 	    ("uma_zfree_debug: called with spinlock or critical section held"));
3096 
3097 #ifdef DEBUG_MEMGUARD
3098 	if ((zone->uz_flags & UMA_ZONE_SMR) == 0 && is_memguard_addr(item)) {
3099 		if (zone->uz_dtor != NULL)
3100 			zone->uz_dtor(item, zone->uz_size, udata);
3101 		if (zone->uz_fini != NULL)
3102 			zone->uz_fini(item, zone->uz_size);
3103 		memguard_free(item);
3104 		return (EJUSTRETURN);
3105 	}
3106 #endif
3107 	return (0);
3108 }
3109 #endif
3110 
3111 static __noinline void *
3112 uma_zalloc_single(uma_zone_t zone, void *udata, int flags)
3113 {
3114 	int domain;
3115 
3116 	/*
3117 	 * We can not get a bucket so try to return a single item.
3118 	 */
3119 	if (zone->uz_flags & UMA_ZONE_FIRSTTOUCH)
3120 		domain = PCPU_GET(domain);
3121 	else
3122 		domain = UMA_ANYDOMAIN;
3123 	return (zone_alloc_item(zone, udata, domain, flags));
3124 }
3125 
3126 /* See uma.h */
3127 void *
3128 uma_zalloc_smr(uma_zone_t zone, int flags)
3129 {
3130 	uma_cache_bucket_t bucket;
3131 	uma_cache_t cache;
3132 	void *item;
3133 	int size, uz_flags;
3134 
3135 #ifdef UMA_ZALLOC_DEBUG
3136 	KASSERT((zone->uz_flags & UMA_ZONE_SMR) != 0,
3137 	    ("uma_zalloc_arg: called with non-SMR zone.\n"));
3138 	if (uma_zalloc_debug(zone, &item, NULL, flags) == EJUSTRETURN)
3139 		return (item);
3140 #endif
3141 
3142 	critical_enter();
3143 	do {
3144 		cache = &zone->uz_cpu[curcpu];
3145 		bucket = &cache->uc_allocbucket;
3146 		size = cache_uz_size(cache);
3147 		uz_flags = cache_uz_flags(cache);
3148 		if (__predict_true(bucket->ucb_cnt != 0)) {
3149 			item = cache_bucket_pop(cache, bucket);
3150 			critical_exit();
3151 			return (item_ctor(zone, uz_flags, size, NULL, flags,
3152 			    item));
3153 		}
3154 	} while (cache_alloc(zone, cache, NULL, flags));
3155 	critical_exit();
3156 
3157 	return (uma_zalloc_single(zone, NULL, flags));
3158 }
3159 
3160 /* See uma.h */
3161 void *
3162 uma_zalloc_arg(uma_zone_t zone, void *udata, int flags)
3163 {
3164 	uma_cache_bucket_t bucket;
3165 	uma_cache_t cache;
3166 	void *item;
3167 	int size, uz_flags;
3168 
3169 	/* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
3170 	random_harvest_fast_uma(&zone, sizeof(zone), RANDOM_UMA);
3171 
3172 	/* This is the fast path allocation */
3173 	CTR3(KTR_UMA, "uma_zalloc_arg zone %s(%p) flags %d", zone->uz_name,
3174 	    zone, flags);
3175 
3176 #ifdef UMA_ZALLOC_DEBUG
3177 	KASSERT((zone->uz_flags & UMA_ZONE_SMR) == 0,
3178 	    ("uma_zalloc_arg: called with SMR zone.\n"));
3179 	if (uma_zalloc_debug(zone, &item, udata, flags) == EJUSTRETURN)
3180 		return (item);
3181 #endif
3182 
3183 	/*
3184 	 * If possible, allocate from the per-CPU cache.  There are two
3185 	 * requirements for safe access to the per-CPU cache: (1) the thread
3186 	 * accessing the cache must not be preempted or yield during access,
3187 	 * and (2) the thread must not migrate CPUs without switching which
3188 	 * cache it accesses.  We rely on a critical section to prevent
3189 	 * preemption and migration.  We release the critical section in
3190 	 * order to acquire the zone mutex if we are unable to allocate from
3191 	 * the current cache; when we re-acquire the critical section, we
3192 	 * must detect and handle migration if it has occurred.
3193 	 */
3194 	critical_enter();
3195 	do {
3196 		cache = &zone->uz_cpu[curcpu];
3197 		bucket = &cache->uc_allocbucket;
3198 		size = cache_uz_size(cache);
3199 		uz_flags = cache_uz_flags(cache);
3200 		if (__predict_true(bucket->ucb_cnt != 0)) {
3201 			item = cache_bucket_pop(cache, bucket);
3202 			critical_exit();
3203 			return (item_ctor(zone, uz_flags, size, udata, flags,
3204 			    item));
3205 		}
3206 	} while (cache_alloc(zone, cache, udata, flags));
3207 	critical_exit();
3208 
3209 	return (uma_zalloc_single(zone, udata, flags));
3210 }
3211 
3212 /*
3213  * Replenish an alloc bucket and possibly restore an old one.  Called in
3214  * a critical section.  Returns in a critical section.
3215  *
3216  * A false return value indicates an allocation failure.
3217  * A true return value indicates success and the caller should retry.
3218  */
3219 static __noinline bool
3220 cache_alloc(uma_zone_t zone, uma_cache_t cache, void *udata, int flags)
3221 {
3222 	uma_zone_domain_t zdom;
3223 	uma_bucket_t bucket;
3224 	int domain;
3225 	bool lockfail;
3226 
3227 	CRITICAL_ASSERT(curthread);
3228 
3229 	/*
3230 	 * If we have run out of items in our alloc bucket see
3231 	 * if we can switch with the free bucket.
3232 	 *
3233 	 * SMR Zones can't re-use the free bucket until the sequence has
3234 	 * expired.
3235 	 */
3236 	if ((zone->uz_flags & UMA_ZONE_SMR) == 0 &&
3237 	    cache->uc_freebucket.ucb_cnt != 0) {
3238 		cache_bucket_swap(&cache->uc_freebucket,
3239 		    &cache->uc_allocbucket);
3240 		return (true);
3241 	}
3242 
3243 	/*
3244 	 * Discard any empty allocation bucket while we hold no locks.
3245 	 */
3246 	bucket = cache_bucket_unload_alloc(cache);
3247 	critical_exit();
3248 	if (bucket != NULL)
3249 		bucket_free(zone, bucket, udata);
3250 
3251 	/* Short-circuit for zones without buckets and low memory. */
3252 	if (zone->uz_bucket_size == 0 || bucketdisable) {
3253 		critical_enter();
3254 		return (false);
3255 	}
3256 
3257 	/*
3258 	 * Attempt to retrieve the item from the per-CPU cache has failed, so
3259 	 * we must go back to the zone.  This requires the zone lock, so we
3260 	 * must drop the critical section, then re-acquire it when we go back
3261 	 * to the cache.  Since the critical section is released, we may be
3262 	 * preempted or migrate.  As such, make sure not to maintain any
3263 	 * thread-local state specific to the cache from prior to releasing
3264 	 * the critical section.
3265 	 */
3266 	lockfail = 0;
3267 	if (ZONE_TRYLOCK(zone) == 0) {
3268 		/* Record contention to size the buckets. */
3269 		ZONE_LOCK(zone);
3270 		lockfail = 1;
3271 	}
3272 
3273 	/* See if we lost the race to fill the cache. */
3274 	critical_enter();
3275 	cache = &zone->uz_cpu[curcpu];
3276 	if (cache->uc_allocbucket.ucb_bucket != NULL) {
3277 		ZONE_UNLOCK(zone);
3278 		return (true);
3279 	}
3280 
3281 	/*
3282 	 * Check the zone's cache of buckets.
3283 	 */
3284 	if (zone->uz_flags & UMA_ZONE_FIRSTTOUCH) {
3285 		domain = PCPU_GET(domain);
3286 		zdom = &zone->uz_domain[domain];
3287 	} else {
3288 		domain = UMA_ANYDOMAIN;
3289 		zdom = &zone->uz_domain[0];
3290 	}
3291 
3292 	if ((bucket = zone_fetch_bucket(zone, zdom)) != NULL) {
3293 		KASSERT(bucket->ub_cnt != 0,
3294 		    ("uma_zalloc_arg: Returning an empty bucket."));
3295 		cache_bucket_load_alloc(cache, bucket);
3296 		return (true);
3297 	}
3298 	/* We are no longer associated with this CPU. */
3299 	critical_exit();
3300 
3301 	/*
3302 	 * We bump the uz count when the cache size is insufficient to
3303 	 * handle the working set.
3304 	 */
3305 	if (lockfail && zone->uz_bucket_size < zone->uz_bucket_size_max)
3306 		zone->uz_bucket_size++;
3307 	ZONE_UNLOCK(zone);
3308 
3309 	/*
3310 	 * Fill a bucket and attempt to use it as the alloc bucket.
3311 	 */
3312 	bucket = zone_alloc_bucket(zone, udata, domain, flags);
3313 	CTR3(KTR_UMA, "uma_zalloc: zone %s(%p) bucket zone returned %p",
3314 	    zone->uz_name, zone, bucket);
3315 	if (bucket == NULL) {
3316 		critical_enter();
3317 		return (false);
3318 	}
3319 
3320 	/*
3321 	 * See if we lost the race or were migrated.  Cache the
3322 	 * initialized bucket to make this less likely or claim
3323 	 * the memory directly.
3324 	 */
3325 	ZONE_LOCK(zone);
3326 	critical_enter();
3327 	cache = &zone->uz_cpu[curcpu];
3328 	if (cache->uc_allocbucket.ucb_bucket == NULL &&
3329 	    ((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) == 0 ||
3330 	    domain == PCPU_GET(domain))) {
3331 		cache_bucket_load_alloc(cache, bucket);
3332 		zdom->uzd_imax += bucket->ub_cnt;
3333 	} else if (zone->uz_bkt_count >= zone->uz_bkt_max) {
3334 		critical_exit();
3335 		ZONE_UNLOCK(zone);
3336 		bucket_drain(zone, bucket);
3337 		bucket_free(zone, bucket, udata);
3338 		critical_enter();
3339 		return (true);
3340 	} else
3341 		zone_put_bucket(zone, zdom, bucket, false);
3342 	ZONE_UNLOCK(zone);
3343 	return (true);
3344 }
3345 
3346 void *
3347 uma_zalloc_domain(uma_zone_t zone, void *udata, int domain, int flags)
3348 {
3349 
3350 	/* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
3351 	random_harvest_fast_uma(&zone, sizeof(zone), RANDOM_UMA);
3352 
3353 	/* This is the fast path allocation */
3354 	CTR4(KTR_UMA, "uma_zalloc_domain zone %s(%p) domain %d flags %d",
3355 	    zone->uz_name, zone, domain, flags);
3356 
3357 	if (flags & M_WAITOK) {
3358 		WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
3359 		    "uma_zalloc_domain: zone \"%s\"", zone->uz_name);
3360 	}
3361 	KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
3362 	    ("uma_zalloc_domain: called with spinlock or critical section held"));
3363 
3364 	return (zone_alloc_item(zone, udata, domain, flags));
3365 }
3366 
3367 /*
3368  * Find a slab with some space.  Prefer slabs that are partially used over those
3369  * that are totally full.  This helps to reduce fragmentation.
3370  *
3371  * If 'rr' is 1, search all domains starting from 'domain'.  Otherwise check
3372  * only 'domain'.
3373  */
3374 static uma_slab_t
3375 keg_first_slab(uma_keg_t keg, int domain, bool rr)
3376 {
3377 	uma_domain_t dom;
3378 	uma_slab_t slab;
3379 	int start;
3380 
3381 	KASSERT(domain >= 0 && domain < vm_ndomains,
3382 	    ("keg_first_slab: domain %d out of range", domain));
3383 	KEG_LOCK_ASSERT(keg, domain);
3384 
3385 	slab = NULL;
3386 	start = domain;
3387 	do {
3388 		dom = &keg->uk_domain[domain];
3389 		if ((slab = LIST_FIRST(&dom->ud_part_slab)) != NULL)
3390 			return (slab);
3391 		if ((slab = LIST_FIRST(&dom->ud_free_slab)) != NULL) {
3392 			LIST_REMOVE(slab, us_link);
3393 			dom->ud_free_slabs--;
3394 			LIST_INSERT_HEAD(&dom->ud_part_slab, slab, us_link);
3395 			return (slab);
3396 		}
3397 		if (rr)
3398 			domain = (domain + 1) % vm_ndomains;
3399 	} while (domain != start);
3400 
3401 	return (NULL);
3402 }
3403 
3404 /*
3405  * Fetch an existing slab from a free or partial list.  Returns with the
3406  * keg domain lock held if a slab was found or unlocked if not.
3407  */
3408 static uma_slab_t
3409 keg_fetch_free_slab(uma_keg_t keg, int domain, bool rr, int flags)
3410 {
3411 	uma_slab_t slab;
3412 	uint32_t reserve;
3413 
3414 	/* HASH has a single free list. */
3415 	if ((keg->uk_flags & UMA_ZFLAG_HASH) != 0)
3416 		domain = 0;
3417 
3418 	KEG_LOCK(keg, domain);
3419 	reserve = (flags & M_USE_RESERVE) != 0 ? 0 : keg->uk_reserve;
3420 	if (keg->uk_domain[domain].ud_free_items <= reserve ||
3421 	    (slab = keg_first_slab(keg, domain, rr)) == NULL) {
3422 		KEG_UNLOCK(keg, domain);
3423 		return (NULL);
3424 	}
3425 	return (slab);
3426 }
3427 
3428 static uma_slab_t
3429 keg_fetch_slab(uma_keg_t keg, uma_zone_t zone, int rdomain, const int flags)
3430 {
3431 	struct vm_domainset_iter di;
3432 	uma_slab_t slab;
3433 	int aflags, domain;
3434 	bool rr;
3435 
3436 restart:
3437 	/*
3438 	 * Use the keg's policy if upper layers haven't already specified a
3439 	 * domain (as happens with first-touch zones).
3440 	 *
3441 	 * To avoid races we run the iterator with the keg lock held, but that
3442 	 * means that we cannot allow the vm_domainset layer to sleep.  Thus,
3443 	 * clear M_WAITOK and handle low memory conditions locally.
3444 	 */
3445 	rr = rdomain == UMA_ANYDOMAIN;
3446 	if (rr) {
3447 		aflags = (flags & ~M_WAITOK) | M_NOWAIT;
3448 		vm_domainset_iter_policy_ref_init(&di, &keg->uk_dr, &domain,
3449 		    &aflags);
3450 	} else {
3451 		aflags = flags;
3452 		domain = rdomain;
3453 	}
3454 
3455 	for (;;) {
3456 		slab = keg_fetch_free_slab(keg, domain, rr, flags);
3457 		if (slab != NULL)
3458 			return (slab);
3459 
3460 		/*
3461 		 * M_NOVM means don't ask at all!
3462 		 */
3463 		if (flags & M_NOVM)
3464 			break;
3465 
3466 		slab = keg_alloc_slab(keg, zone, domain, flags, aflags);
3467 		if (slab != NULL)
3468 			return (slab);
3469 		if (!rr && (flags & M_WAITOK) == 0)
3470 			break;
3471 		if (rr && vm_domainset_iter_policy(&di, &domain) != 0) {
3472 			if ((flags & M_WAITOK) != 0) {
3473 				vm_wait_doms(&keg->uk_dr.dr_policy->ds_mask);
3474 				goto restart;
3475 			}
3476 			break;
3477 		}
3478 	}
3479 
3480 	/*
3481 	 * We might not have been able to get a slab but another cpu
3482 	 * could have while we were unlocked.  Check again before we
3483 	 * fail.
3484 	 */
3485 	if ((slab = keg_fetch_free_slab(keg, domain, rr, flags)) != NULL)
3486 		return (slab);
3487 
3488 	return (NULL);
3489 }
3490 
3491 static void *
3492 slab_alloc_item(uma_keg_t keg, uma_slab_t slab)
3493 {
3494 	uma_domain_t dom;
3495 	void *item;
3496 	int freei;
3497 
3498 	KEG_LOCK_ASSERT(keg, slab->us_domain);
3499 
3500 	dom = &keg->uk_domain[slab->us_domain];
3501 	freei = BIT_FFS(keg->uk_ipers, &slab->us_free) - 1;
3502 	BIT_CLR(keg->uk_ipers, freei, &slab->us_free);
3503 	item = slab_item(slab, keg, freei);
3504 	slab->us_freecount--;
3505 	dom->ud_free_items--;
3506 
3507 	/*
3508 	 * Move this slab to the full list.  It must be on the partial list, so
3509 	 * we do not need to update the free slab count.  In particular,
3510 	 * keg_fetch_slab() always returns slabs on the partial list.
3511 	 */
3512 	if (slab->us_freecount == 0) {
3513 		LIST_REMOVE(slab, us_link);
3514 		LIST_INSERT_HEAD(&dom->ud_full_slab, slab, us_link);
3515 	}
3516 
3517 	return (item);
3518 }
3519 
3520 static int
3521 zone_import(void *arg, void **bucket, int max, int domain, int flags)
3522 {
3523 	uma_domain_t dom;
3524 	uma_zone_t zone;
3525 	uma_slab_t slab;
3526 	uma_keg_t keg;
3527 #ifdef NUMA
3528 	int stripe;
3529 #endif
3530 	int i;
3531 
3532 	zone = arg;
3533 	slab = NULL;
3534 	keg = zone->uz_keg;
3535 	/* Try to keep the buckets totally full */
3536 	for (i = 0; i < max; ) {
3537 		if ((slab = keg_fetch_slab(keg, zone, domain, flags)) == NULL)
3538 			break;
3539 #ifdef NUMA
3540 		stripe = howmany(max, vm_ndomains);
3541 #endif
3542 		dom = &keg->uk_domain[slab->us_domain];
3543 		while (slab->us_freecount && i < max) {
3544 			bucket[i++] = slab_alloc_item(keg, slab);
3545 			if (dom->ud_free_items <= keg->uk_reserve)
3546 				break;
3547 #ifdef NUMA
3548 			/*
3549 			 * If the zone is striped we pick a new slab for every
3550 			 * N allocations.  Eliminating this conditional will
3551 			 * instead pick a new domain for each bucket rather
3552 			 * than stripe within each bucket.  The current option
3553 			 * produces more fragmentation and requires more cpu
3554 			 * time but yields better distribution.
3555 			 */
3556 			if ((zone->uz_flags & UMA_ZONE_ROUNDROBIN) != 0 &&
3557 			    vm_ndomains > 1 && --stripe == 0)
3558 				break;
3559 #endif
3560 		}
3561 		KEG_UNLOCK(keg, slab->us_domain);
3562 		/* Don't block if we allocated any successfully. */
3563 		flags &= ~M_WAITOK;
3564 		flags |= M_NOWAIT;
3565 	}
3566 
3567 	return i;
3568 }
3569 
3570 static int
3571 zone_alloc_limit_hard(uma_zone_t zone, int count, int flags)
3572 {
3573 	uint64_t old, new, total, max;
3574 
3575 	/*
3576 	 * The hard case.  We're going to sleep because there were existing
3577 	 * sleepers or because we ran out of items.  This routine enforces
3578 	 * fairness by keeping fifo order.
3579 	 *
3580 	 * First release our ill gotten gains and make some noise.
3581 	 */
3582 	for (;;) {
3583 		zone_free_limit(zone, count);
3584 		zone_log_warning(zone);
3585 		zone_maxaction(zone);
3586 		if (flags & M_NOWAIT)
3587 			return (0);
3588 
3589 		/*
3590 		 * We need to allocate an item or set ourself as a sleeper
3591 		 * while the sleepq lock is held to avoid wakeup races.  This
3592 		 * is essentially a home rolled semaphore.
3593 		 */
3594 		sleepq_lock(&zone->uz_max_items);
3595 		old = zone->uz_items;
3596 		do {
3597 			MPASS(UZ_ITEMS_SLEEPERS(old) < UZ_ITEMS_SLEEPERS_MAX);
3598 			/* Cache the max since we will evaluate twice. */
3599 			max = zone->uz_max_items;
3600 			if (UZ_ITEMS_SLEEPERS(old) != 0 ||
3601 			    UZ_ITEMS_COUNT(old) >= max)
3602 				new = old + UZ_ITEMS_SLEEPER;
3603 			else
3604 				new = old + MIN(count, max - old);
3605 		} while (atomic_fcmpset_64(&zone->uz_items, &old, new) == 0);
3606 
3607 		/* We may have successfully allocated under the sleepq lock. */
3608 		if (UZ_ITEMS_SLEEPERS(new) == 0) {
3609 			sleepq_release(&zone->uz_max_items);
3610 			return (new - old);
3611 		}
3612 
3613 		/*
3614 		 * This is in a different cacheline from uz_items so that we
3615 		 * don't constantly invalidate the fastpath cacheline when we
3616 		 * adjust item counts.  This could be limited to toggling on
3617 		 * transitions.
3618 		 */
3619 		atomic_add_32(&zone->uz_sleepers, 1);
3620 		atomic_add_64(&zone->uz_sleeps, 1);
3621 
3622 		/*
3623 		 * We have added ourselves as a sleeper.  The sleepq lock
3624 		 * protects us from wakeup races.  Sleep now and then retry.
3625 		 */
3626 		sleepq_add(&zone->uz_max_items, NULL, "zonelimit", 0, 0);
3627 		sleepq_wait(&zone->uz_max_items, PVM);
3628 
3629 		/*
3630 		 * After wakeup, remove ourselves as a sleeper and try
3631 		 * again.  We no longer have the sleepq lock for protection.
3632 		 *
3633 		 * Subract ourselves as a sleeper while attempting to add
3634 		 * our count.
3635 		 */
3636 		atomic_subtract_32(&zone->uz_sleepers, 1);
3637 		old = atomic_fetchadd_64(&zone->uz_items,
3638 		    -(UZ_ITEMS_SLEEPER - count));
3639 		/* We're no longer a sleeper. */
3640 		old -= UZ_ITEMS_SLEEPER;
3641 
3642 		/*
3643 		 * If we're still at the limit, restart.  Notably do not
3644 		 * block on other sleepers.  Cache the max value to protect
3645 		 * against changes via sysctl.
3646 		 */
3647 		total = UZ_ITEMS_COUNT(old);
3648 		max = zone->uz_max_items;
3649 		if (total >= max)
3650 			continue;
3651 		/* Truncate if necessary, otherwise wake other sleepers. */
3652 		if (total + count > max) {
3653 			zone_free_limit(zone, total + count - max);
3654 			count = max - total;
3655 		} else if (total + count < max && UZ_ITEMS_SLEEPERS(old) != 0)
3656 			wakeup_one(&zone->uz_max_items);
3657 
3658 		return (count);
3659 	}
3660 }
3661 
3662 /*
3663  * Allocate 'count' items from our max_items limit.  Returns the number
3664  * available.  If M_NOWAIT is not specified it will sleep until at least
3665  * one item can be allocated.
3666  */
3667 static int
3668 zone_alloc_limit(uma_zone_t zone, int count, int flags)
3669 {
3670 	uint64_t old;
3671 	uint64_t max;
3672 
3673 	max = zone->uz_max_items;
3674 	MPASS(max > 0);
3675 
3676 	/*
3677 	 * We expect normal allocations to succeed with a simple
3678 	 * fetchadd.
3679 	 */
3680 	old = atomic_fetchadd_64(&zone->uz_items, count);
3681 	if (__predict_true(old + count <= max))
3682 		return (count);
3683 
3684 	/*
3685 	 * If we had some items and no sleepers just return the
3686 	 * truncated value.  We have to release the excess space
3687 	 * though because that may wake sleepers who weren't woken
3688 	 * because we were temporarily over the limit.
3689 	 */
3690 	if (old < max) {
3691 		zone_free_limit(zone, (old + count) - max);
3692 		return (max - old);
3693 	}
3694 	return (zone_alloc_limit_hard(zone, count, flags));
3695 }
3696 
3697 /*
3698  * Free a number of items back to the limit.
3699  */
3700 static void
3701 zone_free_limit(uma_zone_t zone, int count)
3702 {
3703 	uint64_t old;
3704 
3705 	MPASS(count > 0);
3706 
3707 	/*
3708 	 * In the common case we either have no sleepers or
3709 	 * are still over the limit and can just return.
3710 	 */
3711 	old = atomic_fetchadd_64(&zone->uz_items, -count);
3712 	if (__predict_true(UZ_ITEMS_SLEEPERS(old) == 0 ||
3713 	   UZ_ITEMS_COUNT(old) - count >= zone->uz_max_items))
3714 		return;
3715 
3716 	/*
3717 	 * Moderate the rate of wakeups.  Sleepers will continue
3718 	 * to generate wakeups if necessary.
3719 	 */
3720 	wakeup_one(&zone->uz_max_items);
3721 }
3722 
3723 static uma_bucket_t
3724 zone_alloc_bucket(uma_zone_t zone, void *udata, int domain, int flags)
3725 {
3726 	uma_bucket_t bucket;
3727 	int maxbucket, cnt;
3728 
3729 	CTR3(KTR_UMA, "zone_alloc_bucket zone %s(%p) domain %d", zone->uz_name,
3730 	    zone, domain);
3731 
3732 	/* Avoid allocs targeting empty domains. */
3733 	if (domain != UMA_ANYDOMAIN && VM_DOMAIN_EMPTY(domain))
3734 		domain = UMA_ANYDOMAIN;
3735 
3736 	if (zone->uz_max_items > 0)
3737 		maxbucket = zone_alloc_limit(zone, zone->uz_bucket_size,
3738 		    M_NOWAIT);
3739 	else
3740 		maxbucket = zone->uz_bucket_size;
3741 	if (maxbucket == 0)
3742 		return (false);
3743 
3744 	/* Don't wait for buckets, preserve caller's NOVM setting. */
3745 	bucket = bucket_alloc(zone, udata, M_NOWAIT | (flags & M_NOVM));
3746 	if (bucket == NULL) {
3747 		cnt = 0;
3748 		goto out;
3749 	}
3750 
3751 	bucket->ub_cnt = zone->uz_import(zone->uz_arg, bucket->ub_bucket,
3752 	    MIN(maxbucket, bucket->ub_entries), domain, flags);
3753 
3754 	/*
3755 	 * Initialize the memory if necessary.
3756 	 */
3757 	if (bucket->ub_cnt != 0 && zone->uz_init != NULL) {
3758 		int i;
3759 
3760 		for (i = 0; i < bucket->ub_cnt; i++)
3761 			if (zone->uz_init(bucket->ub_bucket[i], zone->uz_size,
3762 			    flags) != 0)
3763 				break;
3764 		/*
3765 		 * If we couldn't initialize the whole bucket, put the
3766 		 * rest back onto the freelist.
3767 		 */
3768 		if (i != bucket->ub_cnt) {
3769 			zone->uz_release(zone->uz_arg, &bucket->ub_bucket[i],
3770 			    bucket->ub_cnt - i);
3771 #ifdef INVARIANTS
3772 			bzero(&bucket->ub_bucket[i],
3773 			    sizeof(void *) * (bucket->ub_cnt - i));
3774 #endif
3775 			bucket->ub_cnt = i;
3776 		}
3777 	}
3778 
3779 	cnt = bucket->ub_cnt;
3780 	if (bucket->ub_cnt == 0) {
3781 		bucket_free(zone, bucket, udata);
3782 		counter_u64_add(zone->uz_fails, 1);
3783 		bucket = NULL;
3784 	}
3785 out:
3786 	if (zone->uz_max_items > 0 && cnt < maxbucket)
3787 		zone_free_limit(zone, maxbucket - cnt);
3788 
3789 	return (bucket);
3790 }
3791 
3792 /*
3793  * Allocates a single item from a zone.
3794  *
3795  * Arguments
3796  *	zone   The zone to alloc for.
3797  *	udata  The data to be passed to the constructor.
3798  *	domain The domain to allocate from or UMA_ANYDOMAIN.
3799  *	flags  M_WAITOK, M_NOWAIT, M_ZERO.
3800  *
3801  * Returns
3802  *	NULL if there is no memory and M_NOWAIT is set
3803  *	An item if successful
3804  */
3805 
3806 static void *
3807 zone_alloc_item(uma_zone_t zone, void *udata, int domain, int flags)
3808 {
3809 	void *item;
3810 
3811 	if (zone->uz_max_items > 0 && zone_alloc_limit(zone, 1, flags) == 0)
3812 		return (NULL);
3813 
3814 	/* Avoid allocs targeting empty domains. */
3815 	if (domain != UMA_ANYDOMAIN && VM_DOMAIN_EMPTY(domain))
3816 		domain = UMA_ANYDOMAIN;
3817 
3818 	if (zone->uz_import(zone->uz_arg, &item, 1, domain, flags) != 1)
3819 		goto fail_cnt;
3820 
3821 	/*
3822 	 * We have to call both the zone's init (not the keg's init)
3823 	 * and the zone's ctor.  This is because the item is going from
3824 	 * a keg slab directly to the user, and the user is expecting it
3825 	 * to be both zone-init'd as well as zone-ctor'd.
3826 	 */
3827 	if (zone->uz_init != NULL) {
3828 		if (zone->uz_init(item, zone->uz_size, flags) != 0) {
3829 			zone_free_item(zone, item, udata, SKIP_FINI | SKIP_CNT);
3830 			goto fail_cnt;
3831 		}
3832 	}
3833 	item = item_ctor(zone, zone->uz_flags, zone->uz_size, udata, flags,
3834 	    item);
3835 	if (item == NULL)
3836 		goto fail;
3837 
3838 	counter_u64_add(zone->uz_allocs, 1);
3839 	CTR3(KTR_UMA, "zone_alloc_item item %p from %s(%p)", item,
3840 	    zone->uz_name, zone);
3841 
3842 	return (item);
3843 
3844 fail_cnt:
3845 	counter_u64_add(zone->uz_fails, 1);
3846 fail:
3847 	if (zone->uz_max_items > 0)
3848 		zone_free_limit(zone, 1);
3849 	CTR2(KTR_UMA, "zone_alloc_item failed from %s(%p)",
3850 	    zone->uz_name, zone);
3851 
3852 	return (NULL);
3853 }
3854 
3855 /* See uma.h */
3856 void
3857 uma_zfree_smr(uma_zone_t zone, void *item)
3858 {
3859 	uma_cache_t cache;
3860 	uma_cache_bucket_t bucket;
3861 	int domain, itemdomain, uz_flags;
3862 
3863 #ifdef UMA_ZALLOC_DEBUG
3864 	KASSERT((zone->uz_flags & UMA_ZONE_SMR) != 0,
3865 	    ("uma_zfree_smr: called with non-SMR zone.\n"));
3866 	KASSERT(item != NULL, ("uma_zfree_smr: Called with NULL pointer."));
3867 	if (uma_zfree_debug(zone, item, NULL) == EJUSTRETURN)
3868 		return;
3869 #endif
3870 	cache = &zone->uz_cpu[curcpu];
3871 	uz_flags = cache_uz_flags(cache);
3872 	domain = itemdomain = 0;
3873 #ifdef NUMA
3874 	if ((uz_flags & UMA_ZONE_FIRSTTOUCH) != 0)
3875 		itemdomain = _vm_phys_domain(pmap_kextract((vm_offset_t)item));
3876 #endif
3877 	critical_enter();
3878 	do {
3879 		cache = &zone->uz_cpu[curcpu];
3880 		/* SMR Zones must free to the free bucket. */
3881 		bucket = &cache->uc_freebucket;
3882 #ifdef NUMA
3883 		domain = PCPU_GET(domain);
3884 		if ((uz_flags & UMA_ZONE_FIRSTTOUCH) != 0 &&
3885 		    domain != itemdomain) {
3886 			bucket = &cache->uc_crossbucket;
3887 		}
3888 #endif
3889 		if (__predict_true(bucket->ucb_cnt < bucket->ucb_entries)) {
3890 			cache_bucket_push(cache, bucket, item);
3891 			critical_exit();
3892 			return;
3893 		}
3894 	} while (cache_free(zone, cache, NULL, item, itemdomain));
3895 	critical_exit();
3896 
3897 	/*
3898 	 * If nothing else caught this, we'll just do an internal free.
3899 	 */
3900 	zone_free_item(zone, item, NULL, SKIP_NONE);
3901 }
3902 
3903 /* See uma.h */
3904 void
3905 uma_zfree_arg(uma_zone_t zone, void *item, void *udata)
3906 {
3907 	uma_cache_t cache;
3908 	uma_cache_bucket_t bucket;
3909 	int domain, itemdomain, uz_flags;
3910 
3911 	/* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
3912 	random_harvest_fast_uma(&zone, sizeof(zone), RANDOM_UMA);
3913 
3914 	CTR2(KTR_UMA, "uma_zfree_arg zone %s(%p)", zone->uz_name, zone);
3915 
3916 #ifdef UMA_ZALLOC_DEBUG
3917 	KASSERT((zone->uz_flags & UMA_ZONE_SMR) == 0,
3918 	    ("uma_zfree_arg: called with SMR zone.\n"));
3919 	if (uma_zfree_debug(zone, item, udata) == EJUSTRETURN)
3920 		return;
3921 #endif
3922         /* uma_zfree(..., NULL) does nothing, to match free(9). */
3923         if (item == NULL)
3924                 return;
3925 
3926 	/*
3927 	 * We are accessing the per-cpu cache without a critical section to
3928 	 * fetch size and flags.  This is acceptable, if we are preempted we
3929 	 * will simply read another cpu's line.
3930 	 */
3931 	cache = &zone->uz_cpu[curcpu];
3932 	uz_flags = cache_uz_flags(cache);
3933 	if (UMA_ALWAYS_CTORDTOR ||
3934 	    __predict_false((uz_flags & UMA_ZFLAG_CTORDTOR) != 0))
3935 		item_dtor(zone, item, cache_uz_size(cache), udata, SKIP_NONE);
3936 
3937 	/*
3938 	 * The race here is acceptable.  If we miss it we'll just have to wait
3939 	 * a little longer for the limits to be reset.
3940 	 */
3941 	if (__predict_false(uz_flags & UMA_ZFLAG_LIMIT)) {
3942 		if (zone->uz_sleepers > 0)
3943 			goto zfree_item;
3944 	}
3945 
3946 	/*
3947 	 * If possible, free to the per-CPU cache.  There are two
3948 	 * requirements for safe access to the per-CPU cache: (1) the thread
3949 	 * accessing the cache must not be preempted or yield during access,
3950 	 * and (2) the thread must not migrate CPUs without switching which
3951 	 * cache it accesses.  We rely on a critical section to prevent
3952 	 * preemption and migration.  We release the critical section in
3953 	 * order to acquire the zone mutex if we are unable to free to the
3954 	 * current cache; when we re-acquire the critical section, we must
3955 	 * detect and handle migration if it has occurred.
3956 	 */
3957 	domain = itemdomain = 0;
3958 #ifdef NUMA
3959 	if ((uz_flags & UMA_ZONE_FIRSTTOUCH) != 0)
3960 		itemdomain = _vm_phys_domain(pmap_kextract((vm_offset_t)item));
3961 #endif
3962 	critical_enter();
3963 	do {
3964 		cache = &zone->uz_cpu[curcpu];
3965 		/*
3966 		 * Try to free into the allocbucket first to give LIFO
3967 		 * ordering for cache-hot datastructures.  Spill over
3968 		 * into the freebucket if necessary.  Alloc will swap
3969 		 * them if one runs dry.
3970 		 */
3971 		bucket = &cache->uc_allocbucket;
3972 #ifdef NUMA
3973 		domain = PCPU_GET(domain);
3974 		if ((uz_flags & UMA_ZONE_FIRSTTOUCH) != 0 &&
3975 		    domain != itemdomain) {
3976 			bucket = &cache->uc_crossbucket;
3977 		} else
3978 #endif
3979 		if (bucket->ucb_cnt >= bucket->ucb_entries)
3980 			bucket = &cache->uc_freebucket;
3981 		if (__predict_true(bucket->ucb_cnt < bucket->ucb_entries)) {
3982 			cache_bucket_push(cache, bucket, item);
3983 			critical_exit();
3984 			return;
3985 		}
3986 	} while (cache_free(zone, cache, udata, item, itemdomain));
3987 	critical_exit();
3988 
3989 	/*
3990 	 * If nothing else caught this, we'll just do an internal free.
3991 	 */
3992 zfree_item:
3993 	zone_free_item(zone, item, udata, SKIP_DTOR);
3994 }
3995 
3996 #ifdef NUMA
3997 /*
3998  * sort crossdomain free buckets to domain correct buckets and cache
3999  * them.
4000  */
4001 static void
4002 zone_free_cross(uma_zone_t zone, uma_bucket_t bucket, void *udata)
4003 {
4004 	struct uma_bucketlist fullbuckets;
4005 	uma_zone_domain_t zdom;
4006 	uma_bucket_t b;
4007 	void *item;
4008 	int domain;
4009 
4010 	CTR3(KTR_UMA,
4011 	    "uma_zfree: zone %s(%p) draining cross bucket %p",
4012 	    zone->uz_name, zone, bucket);
4013 
4014 	STAILQ_INIT(&fullbuckets);
4015 
4016 	/*
4017 	 * To avoid having ndomain * ndomain buckets for sorting we have a
4018 	 * lock on the current crossfree bucket.  A full matrix with
4019 	 * per-domain locking could be used if necessary.
4020 	 */
4021 	ZONE_CROSS_LOCK(zone);
4022 	while (bucket->ub_cnt > 0) {
4023 		item = bucket->ub_bucket[bucket->ub_cnt - 1];
4024 		domain = _vm_phys_domain(pmap_kextract((vm_offset_t)item));
4025 		zdom = &zone->uz_domain[domain];
4026 		if (zdom->uzd_cross == NULL) {
4027 			zdom->uzd_cross = bucket_alloc(zone, udata, M_NOWAIT);
4028 			if (zdom->uzd_cross == NULL)
4029 				break;
4030 		}
4031 		zdom->uzd_cross->ub_bucket[zdom->uzd_cross->ub_cnt++] = item;
4032 		if (zdom->uzd_cross->ub_cnt == zdom->uzd_cross->ub_entries) {
4033 			STAILQ_INSERT_HEAD(&fullbuckets, zdom->uzd_cross,
4034 			    ub_link);
4035 			zdom->uzd_cross = NULL;
4036 		}
4037 		bucket->ub_cnt--;
4038 	}
4039 	ZONE_CROSS_UNLOCK(zone);
4040 	if (!STAILQ_EMPTY(&fullbuckets)) {
4041 		ZONE_LOCK(zone);
4042 		while ((b = STAILQ_FIRST(&fullbuckets)) != NULL) {
4043 			if ((zone->uz_flags & UMA_ZONE_SMR) != 0)
4044 				bucket->ub_seq = smr_current(zone->uz_smr);
4045 			STAILQ_REMOVE_HEAD(&fullbuckets, ub_link);
4046 			if (zone->uz_bkt_count >= zone->uz_bkt_max) {
4047 				ZONE_UNLOCK(zone);
4048 				bucket_drain(zone, b);
4049 				bucket_free(zone, b, udata);
4050 				ZONE_LOCK(zone);
4051 			} else {
4052 				domain = _vm_phys_domain(
4053 				    pmap_kextract(
4054 				    (vm_offset_t)b->ub_bucket[0]));
4055 				zdom = &zone->uz_domain[domain];
4056 				zone_put_bucket(zone, zdom, b, true);
4057 			}
4058 		}
4059 		ZONE_UNLOCK(zone);
4060 	}
4061 	if (bucket->ub_cnt != 0)
4062 		bucket_drain(zone, bucket);
4063 	bucket->ub_seq = SMR_SEQ_INVALID;
4064 	bucket_free(zone, bucket, udata);
4065 }
4066 #endif
4067 
4068 static void
4069 zone_free_bucket(uma_zone_t zone, uma_bucket_t bucket, void *udata,
4070     int domain, int itemdomain)
4071 {
4072 	uma_zone_domain_t zdom;
4073 
4074 #ifdef NUMA
4075 	/*
4076 	 * Buckets coming from the wrong domain will be entirely for the
4077 	 * only other domain on two domain systems.  In this case we can
4078 	 * simply cache them.  Otherwise we need to sort them back to
4079 	 * correct domains.
4080 	 */
4081 	if (domain != itemdomain && vm_ndomains > 2) {
4082 		zone_free_cross(zone, bucket, udata);
4083 		return;
4084 	}
4085 #endif
4086 
4087 	/*
4088 	 * Attempt to save the bucket in the zone's domain bucket cache.
4089 	 *
4090 	 * We bump the uz count when the cache size is insufficient to
4091 	 * handle the working set.
4092 	 */
4093 	if (ZONE_TRYLOCK(zone) == 0) {
4094 		/* Record contention to size the buckets. */
4095 		ZONE_LOCK(zone);
4096 		if (zone->uz_bucket_size < zone->uz_bucket_size_max)
4097 			zone->uz_bucket_size++;
4098 	}
4099 
4100 	CTR3(KTR_UMA,
4101 	    "uma_zfree: zone %s(%p) putting bucket %p on free list",
4102 	    zone->uz_name, zone, bucket);
4103 	/* ub_cnt is pointing to the last free item */
4104 	KASSERT(bucket->ub_cnt == bucket->ub_entries,
4105 	    ("uma_zfree: Attempting to insert partial  bucket onto the full list.\n"));
4106 	if (zone->uz_bkt_count >= zone->uz_bkt_max) {
4107 		ZONE_UNLOCK(zone);
4108 		bucket_drain(zone, bucket);
4109 		bucket_free(zone, bucket, udata);
4110 	} else {
4111 		zdom = &zone->uz_domain[itemdomain];
4112 		zone_put_bucket(zone, zdom, bucket, true);
4113 		ZONE_UNLOCK(zone);
4114 	}
4115 }
4116 
4117 /*
4118  * Populate a free or cross bucket for the current cpu cache.  Free any
4119  * existing full bucket either to the zone cache or back to the slab layer.
4120  *
4121  * Enters and returns in a critical section.  false return indicates that
4122  * we can not satisfy this free in the cache layer.  true indicates that
4123  * the caller should retry.
4124  */
4125 static __noinline bool
4126 cache_free(uma_zone_t zone, uma_cache_t cache, void *udata, void *item,
4127     int itemdomain)
4128 {
4129 	uma_cache_bucket_t cbucket;
4130 	uma_bucket_t newbucket, bucket;
4131 	int domain;
4132 
4133 	CRITICAL_ASSERT(curthread);
4134 
4135 	if (zone->uz_bucket_size == 0)
4136 		return false;
4137 
4138 	cache = &zone->uz_cpu[curcpu];
4139 	newbucket = NULL;
4140 
4141 	/*
4142 	 * FIRSTTOUCH domains need to free to the correct zdom.  When
4143 	 * enabled this is the zdom of the item.   The bucket is the
4144 	 * cross bucket if the current domain and itemdomain do not match.
4145 	 */
4146 	cbucket = &cache->uc_freebucket;
4147 #ifdef NUMA
4148 	if ((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) != 0) {
4149 		domain = PCPU_GET(domain);
4150 		if (domain != itemdomain) {
4151 			cbucket = &cache->uc_crossbucket;
4152 			if (cbucket->ucb_cnt != 0)
4153 				atomic_add_64(&zone->uz_xdomain,
4154 				    cbucket->ucb_cnt);
4155 		}
4156 	} else
4157 #endif
4158 		itemdomain = domain = 0;
4159 	bucket = cache_bucket_unload(cbucket);
4160 
4161 	/* We are no longer associated with this CPU. */
4162 	critical_exit();
4163 
4164 	/*
4165 	 * Don't let SMR zones operate without a free bucket.  Force
4166 	 * a synchronize and re-use this one.  We will only degrade
4167 	 * to a synchronize every bucket_size items rather than every
4168 	 * item if we fail to allocate a bucket.
4169 	 */
4170 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0) {
4171 		if (bucket != NULL)
4172 			bucket->ub_seq = smr_advance(zone->uz_smr);
4173 		newbucket = bucket_alloc(zone, udata, M_NOWAIT);
4174 		if (newbucket == NULL && bucket != NULL) {
4175 			bucket_drain(zone, bucket);
4176 			newbucket = bucket;
4177 			bucket = NULL;
4178 		}
4179 	} else if (!bucketdisable)
4180 		newbucket = bucket_alloc(zone, udata, M_NOWAIT);
4181 
4182 	if (bucket != NULL)
4183 		zone_free_bucket(zone, bucket, udata, domain, itemdomain);
4184 
4185 	critical_enter();
4186 	if ((bucket = newbucket) == NULL)
4187 		return (false);
4188 	cache = &zone->uz_cpu[curcpu];
4189 #ifdef NUMA
4190 	/*
4191 	 * Check to see if we should be populating the cross bucket.  If it
4192 	 * is already populated we will fall through and attempt to populate
4193 	 * the free bucket.
4194 	 */
4195 	if ((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) != 0) {
4196 		domain = PCPU_GET(domain);
4197 		if (domain != itemdomain &&
4198 		    cache->uc_crossbucket.ucb_bucket == NULL) {
4199 			cache_bucket_load_cross(cache, bucket);
4200 			return (true);
4201 		}
4202 	}
4203 #endif
4204 	/*
4205 	 * We may have lost the race to fill the bucket or switched CPUs.
4206 	 */
4207 	if (cache->uc_freebucket.ucb_bucket != NULL) {
4208 		critical_exit();
4209 		bucket_free(zone, bucket, udata);
4210 		critical_enter();
4211 	} else
4212 		cache_bucket_load_free(cache, bucket);
4213 
4214 	return (true);
4215 }
4216 
4217 void
4218 uma_zfree_domain(uma_zone_t zone, void *item, void *udata)
4219 {
4220 
4221 	/* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
4222 	random_harvest_fast_uma(&zone, sizeof(zone), RANDOM_UMA);
4223 
4224 	CTR2(KTR_UMA, "uma_zfree_domain zone %s(%p)", zone->uz_name, zone);
4225 
4226 	KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
4227 	    ("uma_zfree_domain: called with spinlock or critical section held"));
4228 
4229         /* uma_zfree(..., NULL) does nothing, to match free(9). */
4230         if (item == NULL)
4231                 return;
4232 	zone_free_item(zone, item, udata, SKIP_NONE);
4233 }
4234 
4235 static void
4236 slab_free_item(uma_zone_t zone, uma_slab_t slab, void *item)
4237 {
4238 	uma_keg_t keg;
4239 	uma_domain_t dom;
4240 	int freei;
4241 
4242 	keg = zone->uz_keg;
4243 	KEG_LOCK_ASSERT(keg, slab->us_domain);
4244 
4245 	/* Do we need to remove from any lists? */
4246 	dom = &keg->uk_domain[slab->us_domain];
4247 	if (slab->us_freecount + 1 == keg->uk_ipers) {
4248 		LIST_REMOVE(slab, us_link);
4249 		LIST_INSERT_HEAD(&dom->ud_free_slab, slab, us_link);
4250 		dom->ud_free_slabs++;
4251 	} else if (slab->us_freecount == 0) {
4252 		LIST_REMOVE(slab, us_link);
4253 		LIST_INSERT_HEAD(&dom->ud_part_slab, slab, us_link);
4254 	}
4255 
4256 	/* Slab management. */
4257 	freei = slab_item_index(slab, keg, item);
4258 	BIT_SET(keg->uk_ipers, freei, &slab->us_free);
4259 	slab->us_freecount++;
4260 
4261 	/* Keg statistics. */
4262 	dom->ud_free_items++;
4263 }
4264 
4265 static void
4266 zone_release(void *arg, void **bucket, int cnt)
4267 {
4268 	struct mtx *lock;
4269 	uma_zone_t zone;
4270 	uma_slab_t slab;
4271 	uma_keg_t keg;
4272 	uint8_t *mem;
4273 	void *item;
4274 	int i;
4275 
4276 	zone = arg;
4277 	keg = zone->uz_keg;
4278 	lock = NULL;
4279 	if (__predict_false((zone->uz_flags & UMA_ZFLAG_HASH) != 0))
4280 		lock = KEG_LOCK(keg, 0);
4281 	for (i = 0; i < cnt; i++) {
4282 		item = bucket[i];
4283 		if (__predict_true((zone->uz_flags & UMA_ZFLAG_VTOSLAB) != 0)) {
4284 			slab = vtoslab((vm_offset_t)item);
4285 		} else {
4286 			mem = (uint8_t *)((uintptr_t)item & (~UMA_SLAB_MASK));
4287 			if ((zone->uz_flags & UMA_ZFLAG_HASH) != 0)
4288 				slab = hash_sfind(&keg->uk_hash, mem);
4289 			else
4290 				slab = (uma_slab_t)(mem + keg->uk_pgoff);
4291 		}
4292 		if (lock != KEG_LOCKPTR(keg, slab->us_domain)) {
4293 			if (lock != NULL)
4294 				mtx_unlock(lock);
4295 			lock = KEG_LOCK(keg, slab->us_domain);
4296 		}
4297 		slab_free_item(zone, slab, item);
4298 	}
4299 	if (lock != NULL)
4300 		mtx_unlock(lock);
4301 }
4302 
4303 /*
4304  * Frees a single item to any zone.
4305  *
4306  * Arguments:
4307  *	zone   The zone to free to
4308  *	item   The item we're freeing
4309  *	udata  User supplied data for the dtor
4310  *	skip   Skip dtors and finis
4311  */
4312 static void
4313 zone_free_item(uma_zone_t zone, void *item, void *udata, enum zfreeskip skip)
4314 {
4315 
4316 	/*
4317 	 * If a free is sent directly to an SMR zone we have to
4318 	 * synchronize immediately because the item can instantly
4319 	 * be reallocated. This should only happen in degenerate
4320 	 * cases when no memory is available for per-cpu caches.
4321 	 */
4322 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0 && skip == SKIP_NONE)
4323 		smr_synchronize(zone->uz_smr);
4324 
4325 	item_dtor(zone, item, zone->uz_size, udata, skip);
4326 
4327 	if (skip < SKIP_FINI && zone->uz_fini)
4328 		zone->uz_fini(item, zone->uz_size);
4329 
4330 	zone->uz_release(zone->uz_arg, &item, 1);
4331 
4332 	if (skip & SKIP_CNT)
4333 		return;
4334 
4335 	counter_u64_add(zone->uz_frees, 1);
4336 
4337 	if (zone->uz_max_items > 0)
4338 		zone_free_limit(zone, 1);
4339 }
4340 
4341 /* See uma.h */
4342 int
4343 uma_zone_set_max(uma_zone_t zone, int nitems)
4344 {
4345 	struct uma_bucket_zone *ubz;
4346 	int count;
4347 
4348 	/*
4349 	 * XXX This can misbehave if the zone has any allocations with
4350 	 * no limit and a limit is imposed.  There is currently no
4351 	 * way to clear a limit.
4352 	 */
4353 	ZONE_LOCK(zone);
4354 	ubz = bucket_zone_max(zone, nitems);
4355 	count = ubz != NULL ? ubz->ubz_entries : 0;
4356 	zone->uz_bucket_size_max = zone->uz_bucket_size = count;
4357 	if (zone->uz_bucket_size_min > zone->uz_bucket_size_max)
4358 		zone->uz_bucket_size_min = zone->uz_bucket_size_max;
4359 	zone->uz_max_items = nitems;
4360 	zone->uz_flags |= UMA_ZFLAG_LIMIT;
4361 	zone_update_caches(zone);
4362 	/* We may need to wake waiters. */
4363 	wakeup(&zone->uz_max_items);
4364 	ZONE_UNLOCK(zone);
4365 
4366 	return (nitems);
4367 }
4368 
4369 /* See uma.h */
4370 void
4371 uma_zone_set_maxcache(uma_zone_t zone, int nitems)
4372 {
4373 	struct uma_bucket_zone *ubz;
4374 	int bpcpu;
4375 
4376 	ZONE_LOCK(zone);
4377 	ubz = bucket_zone_max(zone, nitems);
4378 	if (ubz != NULL) {
4379 		bpcpu = 2;
4380 		if ((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) != 0)
4381 			/* Count the cross-domain bucket. */
4382 			bpcpu++;
4383 		nitems -= ubz->ubz_entries * bpcpu * mp_ncpus;
4384 		zone->uz_bucket_size_max = ubz->ubz_entries;
4385 	} else {
4386 		zone->uz_bucket_size_max = zone->uz_bucket_size = 0;
4387 	}
4388 	if (zone->uz_bucket_size_min > zone->uz_bucket_size_max)
4389 		zone->uz_bucket_size_min = zone->uz_bucket_size_max;
4390 	zone->uz_bkt_max = nitems;
4391 	ZONE_UNLOCK(zone);
4392 }
4393 
4394 /* See uma.h */
4395 int
4396 uma_zone_get_max(uma_zone_t zone)
4397 {
4398 	int nitems;
4399 
4400 	nitems = atomic_load_64(&zone->uz_max_items);
4401 
4402 	return (nitems);
4403 }
4404 
4405 /* See uma.h */
4406 void
4407 uma_zone_set_warning(uma_zone_t zone, const char *warning)
4408 {
4409 
4410 	ZONE_ASSERT_COLD(zone);
4411 	zone->uz_warning = warning;
4412 }
4413 
4414 /* See uma.h */
4415 void
4416 uma_zone_set_maxaction(uma_zone_t zone, uma_maxaction_t maxaction)
4417 {
4418 
4419 	ZONE_ASSERT_COLD(zone);
4420 	TASK_INIT(&zone->uz_maxaction, 0, (task_fn_t *)maxaction, zone);
4421 }
4422 
4423 /* See uma.h */
4424 int
4425 uma_zone_get_cur(uma_zone_t zone)
4426 {
4427 	int64_t nitems;
4428 	u_int i;
4429 
4430 	nitems = 0;
4431 	if (zone->uz_allocs != EARLY_COUNTER && zone->uz_frees != EARLY_COUNTER)
4432 		nitems = counter_u64_fetch(zone->uz_allocs) -
4433 		    counter_u64_fetch(zone->uz_frees);
4434 	CPU_FOREACH(i)
4435 		nitems += atomic_load_64(&zone->uz_cpu[i].uc_allocs) -
4436 		    atomic_load_64(&zone->uz_cpu[i].uc_frees);
4437 
4438 	return (nitems < 0 ? 0 : nitems);
4439 }
4440 
4441 static uint64_t
4442 uma_zone_get_allocs(uma_zone_t zone)
4443 {
4444 	uint64_t nitems;
4445 	u_int i;
4446 
4447 	nitems = 0;
4448 	if (zone->uz_allocs != EARLY_COUNTER)
4449 		nitems = counter_u64_fetch(zone->uz_allocs);
4450 	CPU_FOREACH(i)
4451 		nitems += atomic_load_64(&zone->uz_cpu[i].uc_allocs);
4452 
4453 	return (nitems);
4454 }
4455 
4456 static uint64_t
4457 uma_zone_get_frees(uma_zone_t zone)
4458 {
4459 	uint64_t nitems;
4460 	u_int i;
4461 
4462 	nitems = 0;
4463 	if (zone->uz_frees != EARLY_COUNTER)
4464 		nitems = counter_u64_fetch(zone->uz_frees);
4465 	CPU_FOREACH(i)
4466 		nitems += atomic_load_64(&zone->uz_cpu[i].uc_frees);
4467 
4468 	return (nitems);
4469 }
4470 
4471 #ifdef INVARIANTS
4472 /* Used only for KEG_ASSERT_COLD(). */
4473 static uint64_t
4474 uma_keg_get_allocs(uma_keg_t keg)
4475 {
4476 	uma_zone_t z;
4477 	uint64_t nitems;
4478 
4479 	nitems = 0;
4480 	LIST_FOREACH(z, &keg->uk_zones, uz_link)
4481 		nitems += uma_zone_get_allocs(z);
4482 
4483 	return (nitems);
4484 }
4485 #endif
4486 
4487 /* See uma.h */
4488 void
4489 uma_zone_set_init(uma_zone_t zone, uma_init uminit)
4490 {
4491 	uma_keg_t keg;
4492 
4493 	KEG_GET(zone, keg);
4494 	KEG_ASSERT_COLD(keg);
4495 	keg->uk_init = uminit;
4496 }
4497 
4498 /* See uma.h */
4499 void
4500 uma_zone_set_fini(uma_zone_t zone, uma_fini fini)
4501 {
4502 	uma_keg_t keg;
4503 
4504 	KEG_GET(zone, keg);
4505 	KEG_ASSERT_COLD(keg);
4506 	keg->uk_fini = fini;
4507 }
4508 
4509 /* See uma.h */
4510 void
4511 uma_zone_set_zinit(uma_zone_t zone, uma_init zinit)
4512 {
4513 
4514 	ZONE_ASSERT_COLD(zone);
4515 	zone->uz_init = zinit;
4516 }
4517 
4518 /* See uma.h */
4519 void
4520 uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini)
4521 {
4522 
4523 	ZONE_ASSERT_COLD(zone);
4524 	zone->uz_fini = zfini;
4525 }
4526 
4527 /* See uma.h */
4528 void
4529 uma_zone_set_freef(uma_zone_t zone, uma_free freef)
4530 {
4531 	uma_keg_t keg;
4532 
4533 	KEG_GET(zone, keg);
4534 	KEG_ASSERT_COLD(keg);
4535 	keg->uk_freef = freef;
4536 }
4537 
4538 /* See uma.h */
4539 void
4540 uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf)
4541 {
4542 	uma_keg_t keg;
4543 
4544 	KEG_GET(zone, keg);
4545 	KEG_ASSERT_COLD(keg);
4546 	keg->uk_allocf = allocf;
4547 }
4548 
4549 /* See uma.h */
4550 void
4551 uma_zone_set_smr(uma_zone_t zone, smr_t smr)
4552 {
4553 
4554 	ZONE_ASSERT_COLD(zone);
4555 
4556 	zone->uz_flags |= UMA_ZONE_SMR;
4557 	zone->uz_smr = smr;
4558 	zone_update_caches(zone);
4559 }
4560 
4561 smr_t
4562 uma_zone_get_smr(uma_zone_t zone)
4563 {
4564 
4565 	return (zone->uz_smr);
4566 }
4567 
4568 /* See uma.h */
4569 void
4570 uma_zone_reserve(uma_zone_t zone, int items)
4571 {
4572 	uma_keg_t keg;
4573 
4574 	KEG_GET(zone, keg);
4575 	KEG_ASSERT_COLD(keg);
4576 	keg->uk_reserve = items;
4577 }
4578 
4579 /* See uma.h */
4580 int
4581 uma_zone_reserve_kva(uma_zone_t zone, int count)
4582 {
4583 	uma_keg_t keg;
4584 	vm_offset_t kva;
4585 	u_int pages;
4586 
4587 	KEG_GET(zone, keg);
4588 	KEG_ASSERT_COLD(keg);
4589 	ZONE_ASSERT_COLD(zone);
4590 
4591 	pages = howmany(count, keg->uk_ipers) * keg->uk_ppera;
4592 
4593 #ifdef UMA_MD_SMALL_ALLOC
4594 	if (keg->uk_ppera > 1) {
4595 #else
4596 	if (1) {
4597 #endif
4598 		kva = kva_alloc((vm_size_t)pages * PAGE_SIZE);
4599 		if (kva == 0)
4600 			return (0);
4601 	} else
4602 		kva = 0;
4603 
4604 	ZONE_LOCK(zone);
4605 	MPASS(keg->uk_kva == 0);
4606 	keg->uk_kva = kva;
4607 	keg->uk_offset = 0;
4608 	zone->uz_max_items = pages * keg->uk_ipers;
4609 #ifdef UMA_MD_SMALL_ALLOC
4610 	keg->uk_allocf = (keg->uk_ppera > 1) ? noobj_alloc : uma_small_alloc;
4611 #else
4612 	keg->uk_allocf = noobj_alloc;
4613 #endif
4614 	keg->uk_flags |= UMA_ZFLAG_LIMIT | UMA_ZONE_NOFREE;
4615 	zone->uz_flags |= UMA_ZFLAG_LIMIT | UMA_ZONE_NOFREE;
4616 	zone_update_caches(zone);
4617 	ZONE_UNLOCK(zone);
4618 
4619 	return (1);
4620 }
4621 
4622 /* See uma.h */
4623 void
4624 uma_prealloc(uma_zone_t zone, int items)
4625 {
4626 	struct vm_domainset_iter di;
4627 	uma_domain_t dom;
4628 	uma_slab_t slab;
4629 	uma_keg_t keg;
4630 	int aflags, domain, slabs;
4631 
4632 	KEG_GET(zone, keg);
4633 	slabs = howmany(items, keg->uk_ipers);
4634 	while (slabs-- > 0) {
4635 		aflags = M_NOWAIT;
4636 		vm_domainset_iter_policy_ref_init(&di, &keg->uk_dr, &domain,
4637 		    &aflags);
4638 		for (;;) {
4639 			slab = keg_alloc_slab(keg, zone, domain, M_WAITOK,
4640 			    aflags);
4641 			if (slab != NULL) {
4642 				dom = &keg->uk_domain[slab->us_domain];
4643 				/*
4644 				 * keg_alloc_slab() always returns a slab on the
4645 				 * partial list.
4646 				 */
4647 				LIST_REMOVE(slab, us_link);
4648 				LIST_INSERT_HEAD(&dom->ud_free_slab, slab,
4649 				    us_link);
4650 				dom->ud_free_slabs++;
4651 				KEG_UNLOCK(keg, slab->us_domain);
4652 				break;
4653 			}
4654 			if (vm_domainset_iter_policy(&di, &domain) != 0)
4655 				vm_wait_doms(&keg->uk_dr.dr_policy->ds_mask);
4656 		}
4657 	}
4658 }
4659 
4660 /* See uma.h */
4661 void
4662 uma_reclaim(int req)
4663 {
4664 
4665 	CTR0(KTR_UMA, "UMA: vm asked us to release pages!");
4666 	sx_xlock(&uma_reclaim_lock);
4667 	bucket_enable();
4668 
4669 	switch (req) {
4670 	case UMA_RECLAIM_TRIM:
4671 		zone_foreach(zone_trim, NULL);
4672 		break;
4673 	case UMA_RECLAIM_DRAIN:
4674 	case UMA_RECLAIM_DRAIN_CPU:
4675 		zone_foreach(zone_drain, NULL);
4676 		if (req == UMA_RECLAIM_DRAIN_CPU) {
4677 			pcpu_cache_drain_safe(NULL);
4678 			zone_foreach(zone_drain, NULL);
4679 		}
4680 		break;
4681 	default:
4682 		panic("unhandled reclamation request %d", req);
4683 	}
4684 
4685 	/*
4686 	 * Some slabs may have been freed but this zone will be visited early
4687 	 * we visit again so that we can free pages that are empty once other
4688 	 * zones are drained.  We have to do the same for buckets.
4689 	 */
4690 	zone_drain(slabzones[0], NULL);
4691 	zone_drain(slabzones[1], NULL);
4692 	bucket_zone_drain();
4693 	sx_xunlock(&uma_reclaim_lock);
4694 }
4695 
4696 static volatile int uma_reclaim_needed;
4697 
4698 void
4699 uma_reclaim_wakeup(void)
4700 {
4701 
4702 	if (atomic_fetchadd_int(&uma_reclaim_needed, 1) == 0)
4703 		wakeup(uma_reclaim);
4704 }
4705 
4706 void
4707 uma_reclaim_worker(void *arg __unused)
4708 {
4709 
4710 	for (;;) {
4711 		sx_xlock(&uma_reclaim_lock);
4712 		while (atomic_load_int(&uma_reclaim_needed) == 0)
4713 			sx_sleep(uma_reclaim, &uma_reclaim_lock, PVM, "umarcl",
4714 			    hz);
4715 		sx_xunlock(&uma_reclaim_lock);
4716 		EVENTHANDLER_INVOKE(vm_lowmem, VM_LOW_KMEM);
4717 		uma_reclaim(UMA_RECLAIM_DRAIN_CPU);
4718 		atomic_store_int(&uma_reclaim_needed, 0);
4719 		/* Don't fire more than once per-second. */
4720 		pause("umarclslp", hz);
4721 	}
4722 }
4723 
4724 /* See uma.h */
4725 void
4726 uma_zone_reclaim(uma_zone_t zone, int req)
4727 {
4728 
4729 	switch (req) {
4730 	case UMA_RECLAIM_TRIM:
4731 		zone_trim(zone, NULL);
4732 		break;
4733 	case UMA_RECLAIM_DRAIN:
4734 		zone_drain(zone, NULL);
4735 		break;
4736 	case UMA_RECLAIM_DRAIN_CPU:
4737 		pcpu_cache_drain_safe(zone);
4738 		zone_drain(zone, NULL);
4739 		break;
4740 	default:
4741 		panic("unhandled reclamation request %d", req);
4742 	}
4743 }
4744 
4745 /* See uma.h */
4746 int
4747 uma_zone_exhausted(uma_zone_t zone)
4748 {
4749 
4750 	return (atomic_load_32(&zone->uz_sleepers) > 0);
4751 }
4752 
4753 unsigned long
4754 uma_limit(void)
4755 {
4756 
4757 	return (uma_kmem_limit);
4758 }
4759 
4760 void
4761 uma_set_limit(unsigned long limit)
4762 {
4763 
4764 	uma_kmem_limit = limit;
4765 }
4766 
4767 unsigned long
4768 uma_size(void)
4769 {
4770 
4771 	return (atomic_load_long(&uma_kmem_total));
4772 }
4773 
4774 long
4775 uma_avail(void)
4776 {
4777 
4778 	return (uma_kmem_limit - uma_size());
4779 }
4780 
4781 #ifdef DDB
4782 /*
4783  * Generate statistics across both the zone and its per-cpu cache's.  Return
4784  * desired statistics if the pointer is non-NULL for that statistic.
4785  *
4786  * Note: does not update the zone statistics, as it can't safely clear the
4787  * per-CPU cache statistic.
4788  *
4789  */
4790 static void
4791 uma_zone_sumstat(uma_zone_t z, long *cachefreep, uint64_t *allocsp,
4792     uint64_t *freesp, uint64_t *sleepsp, uint64_t *xdomainp)
4793 {
4794 	uma_cache_t cache;
4795 	uint64_t allocs, frees, sleeps, xdomain;
4796 	int cachefree, cpu;
4797 
4798 	allocs = frees = sleeps = xdomain = 0;
4799 	cachefree = 0;
4800 	CPU_FOREACH(cpu) {
4801 		cache = &z->uz_cpu[cpu];
4802 		cachefree += cache->uc_allocbucket.ucb_cnt;
4803 		cachefree += cache->uc_freebucket.ucb_cnt;
4804 		xdomain += cache->uc_crossbucket.ucb_cnt;
4805 		cachefree += cache->uc_crossbucket.ucb_cnt;
4806 		allocs += cache->uc_allocs;
4807 		frees += cache->uc_frees;
4808 	}
4809 	allocs += counter_u64_fetch(z->uz_allocs);
4810 	frees += counter_u64_fetch(z->uz_frees);
4811 	sleeps += z->uz_sleeps;
4812 	xdomain += z->uz_xdomain;
4813 	if (cachefreep != NULL)
4814 		*cachefreep = cachefree;
4815 	if (allocsp != NULL)
4816 		*allocsp = allocs;
4817 	if (freesp != NULL)
4818 		*freesp = frees;
4819 	if (sleepsp != NULL)
4820 		*sleepsp = sleeps;
4821 	if (xdomainp != NULL)
4822 		*xdomainp = xdomain;
4823 }
4824 #endif /* DDB */
4825 
4826 static int
4827 sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS)
4828 {
4829 	uma_keg_t kz;
4830 	uma_zone_t z;
4831 	int count;
4832 
4833 	count = 0;
4834 	rw_rlock(&uma_rwlock);
4835 	LIST_FOREACH(kz, &uma_kegs, uk_link) {
4836 		LIST_FOREACH(z, &kz->uk_zones, uz_link)
4837 			count++;
4838 	}
4839 	LIST_FOREACH(z, &uma_cachezones, uz_link)
4840 		count++;
4841 
4842 	rw_runlock(&uma_rwlock);
4843 	return (sysctl_handle_int(oidp, &count, 0, req));
4844 }
4845 
4846 static void
4847 uma_vm_zone_stats(struct uma_type_header *uth, uma_zone_t z, struct sbuf *sbuf,
4848     struct uma_percpu_stat *ups, bool internal)
4849 {
4850 	uma_zone_domain_t zdom;
4851 	uma_cache_t cache;
4852 	int i;
4853 
4854 
4855 	for (i = 0; i < vm_ndomains; i++) {
4856 		zdom = &z->uz_domain[i];
4857 		uth->uth_zone_free += zdom->uzd_nitems;
4858 	}
4859 	uth->uth_allocs = counter_u64_fetch(z->uz_allocs);
4860 	uth->uth_frees = counter_u64_fetch(z->uz_frees);
4861 	uth->uth_fails = counter_u64_fetch(z->uz_fails);
4862 	uth->uth_sleeps = z->uz_sleeps;
4863 	uth->uth_xdomain = z->uz_xdomain;
4864 
4865 	/*
4866 	 * While it is not normally safe to access the cache bucket pointers
4867 	 * while not on the CPU that owns the cache, we only allow the pointers
4868 	 * to be exchanged without the zone lock held, not invalidated, so
4869 	 * accept the possible race associated with bucket exchange during
4870 	 * monitoring.  Use atomic_load_ptr() to ensure that the bucket pointers
4871 	 * are loaded only once.
4872 	 */
4873 	for (i = 0; i < mp_maxid + 1; i++) {
4874 		bzero(&ups[i], sizeof(*ups));
4875 		if (internal || CPU_ABSENT(i))
4876 			continue;
4877 		cache = &z->uz_cpu[i];
4878 		ups[i].ups_cache_free += cache->uc_allocbucket.ucb_cnt;
4879 		ups[i].ups_cache_free += cache->uc_freebucket.ucb_cnt;
4880 		ups[i].ups_cache_free += cache->uc_crossbucket.ucb_cnt;
4881 		ups[i].ups_allocs = cache->uc_allocs;
4882 		ups[i].ups_frees = cache->uc_frees;
4883 	}
4884 }
4885 
4886 static int
4887 sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS)
4888 {
4889 	struct uma_stream_header ush;
4890 	struct uma_type_header uth;
4891 	struct uma_percpu_stat *ups;
4892 	struct sbuf sbuf;
4893 	uma_keg_t kz;
4894 	uma_zone_t z;
4895 	uint64_t items;
4896 	uint32_t kfree, pages;
4897 	int count, error, i;
4898 
4899 	error = sysctl_wire_old_buffer(req, 0);
4900 	if (error != 0)
4901 		return (error);
4902 	sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
4903 	sbuf_clear_flags(&sbuf, SBUF_INCLUDENUL);
4904 	ups = malloc((mp_maxid + 1) * sizeof(*ups), M_TEMP, M_WAITOK);
4905 
4906 	count = 0;
4907 	rw_rlock(&uma_rwlock);
4908 	LIST_FOREACH(kz, &uma_kegs, uk_link) {
4909 		LIST_FOREACH(z, &kz->uk_zones, uz_link)
4910 			count++;
4911 	}
4912 
4913 	LIST_FOREACH(z, &uma_cachezones, uz_link)
4914 		count++;
4915 
4916 	/*
4917 	 * Insert stream header.
4918 	 */
4919 	bzero(&ush, sizeof(ush));
4920 	ush.ush_version = UMA_STREAM_VERSION;
4921 	ush.ush_maxcpus = (mp_maxid + 1);
4922 	ush.ush_count = count;
4923 	(void)sbuf_bcat(&sbuf, &ush, sizeof(ush));
4924 
4925 	LIST_FOREACH(kz, &uma_kegs, uk_link) {
4926 		kfree = pages = 0;
4927 		for (i = 0; i < vm_ndomains; i++) {
4928 			kfree += kz->uk_domain[i].ud_free_items;
4929 			pages += kz->uk_domain[i].ud_pages;
4930 		}
4931 		LIST_FOREACH(z, &kz->uk_zones, uz_link) {
4932 			bzero(&uth, sizeof(uth));
4933 			ZONE_LOCK(z);
4934 			strlcpy(uth.uth_name, z->uz_name, UTH_MAX_NAME);
4935 			uth.uth_align = kz->uk_align;
4936 			uth.uth_size = kz->uk_size;
4937 			uth.uth_rsize = kz->uk_rsize;
4938 			if (z->uz_max_items > 0) {
4939 				items = UZ_ITEMS_COUNT(z->uz_items);
4940 				uth.uth_pages = (items / kz->uk_ipers) *
4941 					kz->uk_ppera;
4942 			} else
4943 				uth.uth_pages = pages;
4944 			uth.uth_maxpages = (z->uz_max_items / kz->uk_ipers) *
4945 			    kz->uk_ppera;
4946 			uth.uth_limit = z->uz_max_items;
4947 			uth.uth_keg_free = kfree;
4948 
4949 			/*
4950 			 * A zone is secondary is it is not the first entry
4951 			 * on the keg's zone list.
4952 			 */
4953 			if ((z->uz_flags & UMA_ZONE_SECONDARY) &&
4954 			    (LIST_FIRST(&kz->uk_zones) != z))
4955 				uth.uth_zone_flags = UTH_ZONE_SECONDARY;
4956 			uma_vm_zone_stats(&uth, z, &sbuf, ups,
4957 			    kz->uk_flags & UMA_ZFLAG_INTERNAL);
4958 			ZONE_UNLOCK(z);
4959 			(void)sbuf_bcat(&sbuf, &uth, sizeof(uth));
4960 			for (i = 0; i < mp_maxid + 1; i++)
4961 				(void)sbuf_bcat(&sbuf, &ups[i], sizeof(ups[i]));
4962 		}
4963 	}
4964 	LIST_FOREACH(z, &uma_cachezones, uz_link) {
4965 		bzero(&uth, sizeof(uth));
4966 		ZONE_LOCK(z);
4967 		strlcpy(uth.uth_name, z->uz_name, UTH_MAX_NAME);
4968 		uth.uth_size = z->uz_size;
4969 		uma_vm_zone_stats(&uth, z, &sbuf, ups, false);
4970 		ZONE_UNLOCK(z);
4971 		(void)sbuf_bcat(&sbuf, &uth, sizeof(uth));
4972 		for (i = 0; i < mp_maxid + 1; i++)
4973 			(void)sbuf_bcat(&sbuf, &ups[i], sizeof(ups[i]));
4974 	}
4975 
4976 	rw_runlock(&uma_rwlock);
4977 	error = sbuf_finish(&sbuf);
4978 	sbuf_delete(&sbuf);
4979 	free(ups, M_TEMP);
4980 	return (error);
4981 }
4982 
4983 int
4984 sysctl_handle_uma_zone_max(SYSCTL_HANDLER_ARGS)
4985 {
4986 	uma_zone_t zone = *(uma_zone_t *)arg1;
4987 	int error, max;
4988 
4989 	max = uma_zone_get_max(zone);
4990 	error = sysctl_handle_int(oidp, &max, 0, req);
4991 	if (error || !req->newptr)
4992 		return (error);
4993 
4994 	uma_zone_set_max(zone, max);
4995 
4996 	return (0);
4997 }
4998 
4999 int
5000 sysctl_handle_uma_zone_cur(SYSCTL_HANDLER_ARGS)
5001 {
5002 	uma_zone_t zone;
5003 	int cur;
5004 
5005 	/*
5006 	 * Some callers want to add sysctls for global zones that
5007 	 * may not yet exist so they pass a pointer to a pointer.
5008 	 */
5009 	if (arg2 == 0)
5010 		zone = *(uma_zone_t *)arg1;
5011 	else
5012 		zone = arg1;
5013 	cur = uma_zone_get_cur(zone);
5014 	return (sysctl_handle_int(oidp, &cur, 0, req));
5015 }
5016 
5017 static int
5018 sysctl_handle_uma_zone_allocs(SYSCTL_HANDLER_ARGS)
5019 {
5020 	uma_zone_t zone = arg1;
5021 	uint64_t cur;
5022 
5023 	cur = uma_zone_get_allocs(zone);
5024 	return (sysctl_handle_64(oidp, &cur, 0, req));
5025 }
5026 
5027 static int
5028 sysctl_handle_uma_zone_frees(SYSCTL_HANDLER_ARGS)
5029 {
5030 	uma_zone_t zone = arg1;
5031 	uint64_t cur;
5032 
5033 	cur = uma_zone_get_frees(zone);
5034 	return (sysctl_handle_64(oidp, &cur, 0, req));
5035 }
5036 
5037 static int
5038 sysctl_handle_uma_zone_flags(SYSCTL_HANDLER_ARGS)
5039 {
5040 	struct sbuf sbuf;
5041 	uma_zone_t zone = arg1;
5042 	int error;
5043 
5044 	sbuf_new_for_sysctl(&sbuf, NULL, 0, req);
5045 	if (zone->uz_flags != 0)
5046 		sbuf_printf(&sbuf, "0x%b", zone->uz_flags, PRINT_UMA_ZFLAGS);
5047 	else
5048 		sbuf_printf(&sbuf, "0");
5049 	error = sbuf_finish(&sbuf);
5050 	sbuf_delete(&sbuf);
5051 
5052 	return (error);
5053 }
5054 
5055 static int
5056 sysctl_handle_uma_slab_efficiency(SYSCTL_HANDLER_ARGS)
5057 {
5058 	uma_keg_t keg = arg1;
5059 	int avail, effpct, total;
5060 
5061 	total = keg->uk_ppera * PAGE_SIZE;
5062 	if ((keg->uk_flags & UMA_ZFLAG_OFFPAGE) != 0)
5063 		total += slabzone(keg->uk_ipers)->uz_keg->uk_rsize;
5064 	/*
5065 	 * We consider the client's requested size and alignment here, not the
5066 	 * real size determination uk_rsize, because we also adjust the real
5067 	 * size for internal implementation reasons (max bitset size).
5068 	 */
5069 	avail = keg->uk_ipers * roundup2(keg->uk_size, keg->uk_align + 1);
5070 	if ((keg->uk_flags & UMA_ZONE_PCPU) != 0)
5071 		avail *= mp_maxid + 1;
5072 	effpct = 100 * avail / total;
5073 	return (sysctl_handle_int(oidp, &effpct, 0, req));
5074 }
5075 
5076 static int
5077 sysctl_handle_uma_zone_items(SYSCTL_HANDLER_ARGS)
5078 {
5079 	uma_zone_t zone = arg1;
5080 	uint64_t cur;
5081 
5082 	cur = UZ_ITEMS_COUNT(atomic_load_64(&zone->uz_items));
5083 	return (sysctl_handle_64(oidp, &cur, 0, req));
5084 }
5085 
5086 #ifdef INVARIANTS
5087 static uma_slab_t
5088 uma_dbg_getslab(uma_zone_t zone, void *item)
5089 {
5090 	uma_slab_t slab;
5091 	uma_keg_t keg;
5092 	uint8_t *mem;
5093 
5094 	/*
5095 	 * It is safe to return the slab here even though the
5096 	 * zone is unlocked because the item's allocation state
5097 	 * essentially holds a reference.
5098 	 */
5099 	mem = (uint8_t *)((uintptr_t)item & (~UMA_SLAB_MASK));
5100 	if ((zone->uz_flags & UMA_ZFLAG_CACHE) != 0)
5101 		return (NULL);
5102 	if (zone->uz_flags & UMA_ZFLAG_VTOSLAB)
5103 		return (vtoslab((vm_offset_t)mem));
5104 	keg = zone->uz_keg;
5105 	if ((keg->uk_flags & UMA_ZFLAG_HASH) == 0)
5106 		return ((uma_slab_t)(mem + keg->uk_pgoff));
5107 	KEG_LOCK(keg, 0);
5108 	slab = hash_sfind(&keg->uk_hash, mem);
5109 	KEG_UNLOCK(keg, 0);
5110 
5111 	return (slab);
5112 }
5113 
5114 static bool
5115 uma_dbg_zskip(uma_zone_t zone, void *mem)
5116 {
5117 
5118 	if ((zone->uz_flags & UMA_ZFLAG_CACHE) != 0)
5119 		return (true);
5120 
5121 	return (uma_dbg_kskip(zone->uz_keg, mem));
5122 }
5123 
5124 static bool
5125 uma_dbg_kskip(uma_keg_t keg, void *mem)
5126 {
5127 	uintptr_t idx;
5128 
5129 	if (dbg_divisor == 0)
5130 		return (true);
5131 
5132 	if (dbg_divisor == 1)
5133 		return (false);
5134 
5135 	idx = (uintptr_t)mem >> PAGE_SHIFT;
5136 	if (keg->uk_ipers > 1) {
5137 		idx *= keg->uk_ipers;
5138 		idx += ((uintptr_t)mem & PAGE_MASK) / keg->uk_rsize;
5139 	}
5140 
5141 	if ((idx / dbg_divisor) * dbg_divisor != idx) {
5142 		counter_u64_add(uma_skip_cnt, 1);
5143 		return (true);
5144 	}
5145 	counter_u64_add(uma_dbg_cnt, 1);
5146 
5147 	return (false);
5148 }
5149 
5150 /*
5151  * Set up the slab's freei data such that uma_dbg_free can function.
5152  *
5153  */
5154 static void
5155 uma_dbg_alloc(uma_zone_t zone, uma_slab_t slab, void *item)
5156 {
5157 	uma_keg_t keg;
5158 	int freei;
5159 
5160 	if (slab == NULL) {
5161 		slab = uma_dbg_getslab(zone, item);
5162 		if (slab == NULL)
5163 			panic("uma: item %p did not belong to zone %s\n",
5164 			    item, zone->uz_name);
5165 	}
5166 	keg = zone->uz_keg;
5167 	freei = slab_item_index(slab, keg, item);
5168 
5169 	if (BIT_ISSET(keg->uk_ipers, freei, slab_dbg_bits(slab, keg)))
5170 		panic("Duplicate alloc of %p from zone %p(%s) slab %p(%d)\n",
5171 		    item, zone, zone->uz_name, slab, freei);
5172 	BIT_SET_ATOMIC(keg->uk_ipers, freei, slab_dbg_bits(slab, keg));
5173 }
5174 
5175 /*
5176  * Verifies freed addresses.  Checks for alignment, valid slab membership
5177  * and duplicate frees.
5178  *
5179  */
5180 static void
5181 uma_dbg_free(uma_zone_t zone, uma_slab_t slab, void *item)
5182 {
5183 	uma_keg_t keg;
5184 	int freei;
5185 
5186 	if (slab == NULL) {
5187 		slab = uma_dbg_getslab(zone, item);
5188 		if (slab == NULL)
5189 			panic("uma: Freed item %p did not belong to zone %s\n",
5190 			    item, zone->uz_name);
5191 	}
5192 	keg = zone->uz_keg;
5193 	freei = slab_item_index(slab, keg, item);
5194 
5195 	if (freei >= keg->uk_ipers)
5196 		panic("Invalid free of %p from zone %p(%s) slab %p(%d)\n",
5197 		    item, zone, zone->uz_name, slab, freei);
5198 
5199 	if (slab_item(slab, keg, freei) != item)
5200 		panic("Unaligned free of %p from zone %p(%s) slab %p(%d)\n",
5201 		    item, zone, zone->uz_name, slab, freei);
5202 
5203 	if (!BIT_ISSET(keg->uk_ipers, freei, slab_dbg_bits(slab, keg)))
5204 		panic("Duplicate free of %p from zone %p(%s) slab %p(%d)\n",
5205 		    item, zone, zone->uz_name, slab, freei);
5206 
5207 	BIT_CLR_ATOMIC(keg->uk_ipers, freei, slab_dbg_bits(slab, keg));
5208 }
5209 #endif /* INVARIANTS */
5210 
5211 #ifdef DDB
5212 static int64_t
5213 get_uma_stats(uma_keg_t kz, uma_zone_t z, uint64_t *allocs, uint64_t *used,
5214     uint64_t *sleeps, long *cachefree, uint64_t *xdomain)
5215 {
5216 	uint64_t frees;
5217 	int i;
5218 
5219 	if (kz->uk_flags & UMA_ZFLAG_INTERNAL) {
5220 		*allocs = counter_u64_fetch(z->uz_allocs);
5221 		frees = counter_u64_fetch(z->uz_frees);
5222 		*sleeps = z->uz_sleeps;
5223 		*cachefree = 0;
5224 		*xdomain = 0;
5225 	} else
5226 		uma_zone_sumstat(z, cachefree, allocs, &frees, sleeps,
5227 		    xdomain);
5228 	for (i = 0; i < vm_ndomains; i++) {
5229 		*cachefree += z->uz_domain[i].uzd_nitems;
5230 		if (!((z->uz_flags & UMA_ZONE_SECONDARY) &&
5231 		    (LIST_FIRST(&kz->uk_zones) != z)))
5232 			*cachefree += kz->uk_domain[i].ud_free_items;
5233 	}
5234 	*used = *allocs - frees;
5235 	return (((int64_t)*used + *cachefree) * kz->uk_size);
5236 }
5237 
5238 DB_SHOW_COMMAND(uma, db_show_uma)
5239 {
5240 	const char *fmt_hdr, *fmt_entry;
5241 	uma_keg_t kz;
5242 	uma_zone_t z;
5243 	uint64_t allocs, used, sleeps, xdomain;
5244 	long cachefree;
5245 	/* variables for sorting */
5246 	uma_keg_t cur_keg;
5247 	uma_zone_t cur_zone, last_zone;
5248 	int64_t cur_size, last_size, size;
5249 	int ties;
5250 
5251 	/* /i option produces machine-parseable CSV output */
5252 	if (modif[0] == 'i') {
5253 		fmt_hdr = "%s,%s,%s,%s,%s,%s,%s,%s,%s\n";
5254 		fmt_entry = "\"%s\",%ju,%jd,%ld,%ju,%ju,%u,%jd,%ju\n";
5255 	} else {
5256 		fmt_hdr = "%18s %6s %7s %7s %11s %7s %7s %10s %8s\n";
5257 		fmt_entry = "%18s %6ju %7jd %7ld %11ju %7ju %7u %10jd %8ju\n";
5258 	}
5259 
5260 	db_printf(fmt_hdr, "Zone", "Size", "Used", "Free", "Requests",
5261 	    "Sleeps", "Bucket", "Total Mem", "XFree");
5262 
5263 	/* Sort the zones with largest size first. */
5264 	last_zone = NULL;
5265 	last_size = INT64_MAX;
5266 	for (;;) {
5267 		cur_zone = NULL;
5268 		cur_size = -1;
5269 		ties = 0;
5270 		LIST_FOREACH(kz, &uma_kegs, uk_link) {
5271 			LIST_FOREACH(z, &kz->uk_zones, uz_link) {
5272 				/*
5273 				 * In the case of size ties, print out zones
5274 				 * in the order they are encountered.  That is,
5275 				 * when we encounter the most recently output
5276 				 * zone, we have already printed all preceding
5277 				 * ties, and we must print all following ties.
5278 				 */
5279 				if (z == last_zone) {
5280 					ties = 1;
5281 					continue;
5282 				}
5283 				size = get_uma_stats(kz, z, &allocs, &used,
5284 				    &sleeps, &cachefree, &xdomain);
5285 				if (size > cur_size && size < last_size + ties)
5286 				{
5287 					cur_size = size;
5288 					cur_zone = z;
5289 					cur_keg = kz;
5290 				}
5291 			}
5292 		}
5293 		if (cur_zone == NULL)
5294 			break;
5295 
5296 		size = get_uma_stats(cur_keg, cur_zone, &allocs, &used,
5297 		    &sleeps, &cachefree, &xdomain);
5298 		db_printf(fmt_entry, cur_zone->uz_name,
5299 		    (uintmax_t)cur_keg->uk_size, (intmax_t)used, cachefree,
5300 		    (uintmax_t)allocs, (uintmax_t)sleeps,
5301 		    (unsigned)cur_zone->uz_bucket_size, (intmax_t)size,
5302 		    xdomain);
5303 
5304 		if (db_pager_quit)
5305 			return;
5306 		last_zone = cur_zone;
5307 		last_size = cur_size;
5308 	}
5309 }
5310 
5311 DB_SHOW_COMMAND(umacache, db_show_umacache)
5312 {
5313 	uma_zone_t z;
5314 	uint64_t allocs, frees;
5315 	long cachefree;
5316 	int i;
5317 
5318 	db_printf("%18s %8s %8s %8s %12s %8s\n", "Zone", "Size", "Used", "Free",
5319 	    "Requests", "Bucket");
5320 	LIST_FOREACH(z, &uma_cachezones, uz_link) {
5321 		uma_zone_sumstat(z, &cachefree, &allocs, &frees, NULL, NULL);
5322 		for (i = 0; i < vm_ndomains; i++)
5323 			cachefree += z->uz_domain[i].uzd_nitems;
5324 		db_printf("%18s %8ju %8jd %8ld %12ju %8u\n",
5325 		    z->uz_name, (uintmax_t)z->uz_size,
5326 		    (intmax_t)(allocs - frees), cachefree,
5327 		    (uintmax_t)allocs, z->uz_bucket_size);
5328 		if (db_pager_quit)
5329 			return;
5330 	}
5331 }
5332 #endif	/* DDB */
5333