xref: /freebsd/sys/vm/uma_core.c (revision dc58b3fca5e7a7bb1e9aa640667944d0fe0601cd)
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/asan.h>
62 #include <sys/bitset.h>
63 #include <sys/domainset.h>
64 #include <sys/eventhandler.h>
65 #include <sys/kernel.h>
66 #include <sys/types.h>
67 #include <sys/limits.h>
68 #include <sys/queue.h>
69 #include <sys/malloc.h>
70 #include <sys/ktr.h>
71 #include <sys/lock.h>
72 #include <sys/msan.h>
73 #include <sys/mutex.h>
74 #include <sys/proc.h>
75 #include <sys/random.h>
76 #include <sys/rwlock.h>
77 #include <sys/sbuf.h>
78 #include <sys/sched.h>
79 #include <sys/sleepqueue.h>
80 #include <sys/smp.h>
81 #include <sys/smr.h>
82 #include <sys/sysctl.h>
83 #include <sys/taskqueue.h>
84 #include <sys/vmmeter.h>
85 
86 #include <vm/vm.h>
87 #include <vm/vm_param.h>
88 #include <vm/vm_domainset.h>
89 #include <vm/vm_object.h>
90 #include <vm/vm_page.h>
91 #include <vm/vm_pageout.h>
92 #include <vm/vm_phys.h>
93 #include <vm/vm_pagequeue.h>
94 #include <vm/vm_map.h>
95 #include <vm/vm_kern.h>
96 #include <vm/vm_extern.h>
97 #include <vm/vm_dumpset.h>
98 #include <vm/uma.h>
99 #include <vm/uma_int.h>
100 #include <vm/uma_dbg.h>
101 
102 #include <ddb/ddb.h>
103 
104 #ifdef DEBUG_MEMGUARD
105 #include <vm/memguard.h>
106 #endif
107 
108 #include <machine/md_var.h>
109 
110 #ifdef INVARIANTS
111 #define	UMA_ALWAYS_CTORDTOR	1
112 #else
113 #define	UMA_ALWAYS_CTORDTOR	0
114 #endif
115 
116 /*
117  * This is the zone and keg from which all zones are spawned.
118  */
119 static uma_zone_t kegs;
120 static uma_zone_t zones;
121 
122 /*
123  * On INVARIANTS builds, the slab contains a second bitset of the same size,
124  * "dbg_bits", which is laid out immediately after us_free.
125  */
126 #ifdef INVARIANTS
127 #define	SLAB_BITSETS	2
128 #else
129 #define	SLAB_BITSETS	1
130 #endif
131 
132 /*
133  * These are the two zones from which all offpage uma_slab_ts are allocated.
134  *
135  * One zone is for slab headers that can represent a larger number of items,
136  * making the slabs themselves more efficient, and the other zone is for
137  * headers that are smaller and represent fewer items, making the headers more
138  * efficient.
139  */
140 #define	SLABZONE_SIZE(setsize)					\
141     (sizeof(struct uma_hash_slab) + BITSET_SIZE(setsize) * SLAB_BITSETS)
142 #define	SLABZONE0_SETSIZE	(PAGE_SIZE / 16)
143 #define	SLABZONE1_SETSIZE	SLAB_MAX_SETSIZE
144 #define	SLABZONE0_SIZE	SLABZONE_SIZE(SLABZONE0_SETSIZE)
145 #define	SLABZONE1_SIZE	SLABZONE_SIZE(SLABZONE1_SETSIZE)
146 static uma_zone_t slabzones[2];
147 
148 /*
149  * The initial hash tables come out of this zone so they can be allocated
150  * prior to malloc coming up.
151  */
152 static uma_zone_t hashzone;
153 
154 /* The boot-time adjusted value for cache line alignment. */
155 int uma_align_cache = 64 - 1;
156 
157 static MALLOC_DEFINE(M_UMAHASH, "UMAHash", "UMA Hash Buckets");
158 static MALLOC_DEFINE(M_UMA, "UMA", "UMA Misc");
159 
160 /*
161  * Are we allowed to allocate buckets?
162  */
163 static int bucketdisable = 1;
164 
165 /* Linked list of all kegs in the system */
166 static LIST_HEAD(,uma_keg) uma_kegs = LIST_HEAD_INITIALIZER(uma_kegs);
167 
168 /* Linked list of all cache-only zones in the system */
169 static LIST_HEAD(,uma_zone) uma_cachezones =
170     LIST_HEAD_INITIALIZER(uma_cachezones);
171 
172 /*
173  * Mutex for global lists: uma_kegs, uma_cachezones, and the per-keg list of
174  * zones.
175  */
176 static struct rwlock_padalign __exclusive_cache_line uma_rwlock;
177 
178 static struct sx uma_reclaim_lock;
179 
180 /*
181  * First available virual address for boot time allocations.
182  */
183 static vm_offset_t bootstart;
184 static vm_offset_t bootmem;
185 
186 /*
187  * kmem soft limit, initialized by uma_set_limit().  Ensure that early
188  * allocations don't trigger a wakeup of the reclaim thread.
189  */
190 unsigned long uma_kmem_limit = LONG_MAX;
191 SYSCTL_ULONG(_vm, OID_AUTO, uma_kmem_limit, CTLFLAG_RD, &uma_kmem_limit, 0,
192     "UMA kernel memory soft limit");
193 unsigned long uma_kmem_total;
194 SYSCTL_ULONG(_vm, OID_AUTO, uma_kmem_total, CTLFLAG_RD, &uma_kmem_total, 0,
195     "UMA kernel memory usage");
196 
197 /* Is the VM done starting up? */
198 static enum {
199 	BOOT_COLD,
200 	BOOT_KVA,
201 	BOOT_PCPU,
202 	BOOT_RUNNING,
203 	BOOT_SHUTDOWN,
204 } booted = BOOT_COLD;
205 
206 /*
207  * This is the handle used to schedule events that need to happen
208  * outside of the allocation fast path.
209  */
210 static struct timeout_task uma_timeout_task;
211 #define	UMA_TIMEOUT	20		/* Seconds for callout interval. */
212 
213 /*
214  * This structure is passed as the zone ctor arg so that I don't have to create
215  * a special allocation function just for zones.
216  */
217 struct uma_zctor_args {
218 	const char *name;
219 	size_t size;
220 	uma_ctor ctor;
221 	uma_dtor dtor;
222 	uma_init uminit;
223 	uma_fini fini;
224 	uma_import import;
225 	uma_release release;
226 	void *arg;
227 	uma_keg_t keg;
228 	int align;
229 	uint32_t flags;
230 };
231 
232 struct uma_kctor_args {
233 	uma_zone_t zone;
234 	size_t size;
235 	uma_init uminit;
236 	uma_fini fini;
237 	int align;
238 	uint32_t flags;
239 };
240 
241 struct uma_bucket_zone {
242 	uma_zone_t	ubz_zone;
243 	const char	*ubz_name;
244 	int		ubz_entries;	/* Number of items it can hold. */
245 	int		ubz_maxsize;	/* Maximum allocation size per-item. */
246 };
247 
248 /*
249  * Compute the actual number of bucket entries to pack them in power
250  * of two sizes for more efficient space utilization.
251  */
252 #define	BUCKET_SIZE(n)						\
253     (((sizeof(void *) * (n)) - sizeof(struct uma_bucket)) / sizeof(void *))
254 
255 #define	BUCKET_MAX	BUCKET_SIZE(256)
256 
257 struct uma_bucket_zone bucket_zones[] = {
258 	/* Literal bucket sizes. */
259 	{ NULL, "2 Bucket", 2, 4096 },
260 	{ NULL, "4 Bucket", 4, 3072 },
261 	{ NULL, "8 Bucket", 8, 2048 },
262 	{ NULL, "16 Bucket", 16, 1024 },
263 	/* Rounded down power of 2 sizes for efficiency. */
264 	{ NULL, "32 Bucket", BUCKET_SIZE(32), 512 },
265 	{ NULL, "64 Bucket", BUCKET_SIZE(64), 256 },
266 	{ NULL, "128 Bucket", BUCKET_SIZE(128), 128 },
267 	{ NULL, "256 Bucket", BUCKET_SIZE(256), 64 },
268 	{ NULL, NULL, 0}
269 };
270 
271 /*
272  * Flags and enumerations to be passed to internal functions.
273  */
274 enum zfreeskip {
275 	SKIP_NONE =	0,
276 	SKIP_CNT =	0x00000001,
277 	SKIP_DTOR =	0x00010000,
278 	SKIP_FINI =	0x00020000,
279 };
280 
281 /* Prototypes.. */
282 
283 void	uma_startup1(vm_offset_t);
284 void	uma_startup2(void);
285 
286 static void *noobj_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
287 static void *page_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
288 static void *pcpu_page_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
289 static void *startup_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
290 static void *contig_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
291 static void page_free(void *, vm_size_t, uint8_t);
292 static void pcpu_page_free(void *, vm_size_t, uint8_t);
293 static uma_slab_t keg_alloc_slab(uma_keg_t, uma_zone_t, int, int, int);
294 static void cache_drain(uma_zone_t);
295 static void bucket_drain(uma_zone_t, uma_bucket_t);
296 static void bucket_cache_reclaim(uma_zone_t zone, bool, int);
297 static bool bucket_cache_reclaim_domain(uma_zone_t, bool, bool, int);
298 static int keg_ctor(void *, int, void *, int);
299 static void keg_dtor(void *, int, void *);
300 static void keg_drain(uma_keg_t keg, int domain);
301 static int zone_ctor(void *, int, void *, int);
302 static void zone_dtor(void *, int, void *);
303 static inline void item_dtor(uma_zone_t zone, void *item, int size,
304     void *udata, enum zfreeskip skip);
305 static int zero_init(void *, int, int);
306 static void zone_free_bucket(uma_zone_t zone, uma_bucket_t bucket, void *udata,
307     int itemdomain, bool ws);
308 static void zone_foreach(void (*zfunc)(uma_zone_t, void *), void *);
309 static void zone_foreach_unlocked(void (*zfunc)(uma_zone_t, void *), void *);
310 static void zone_timeout(uma_zone_t zone, void *);
311 static int hash_alloc(struct uma_hash *, u_int);
312 static int hash_expand(struct uma_hash *, struct uma_hash *);
313 static void hash_free(struct uma_hash *hash);
314 static void uma_timeout(void *, int);
315 static void uma_shutdown(void);
316 static void *zone_alloc_item(uma_zone_t, void *, int, int);
317 static void zone_free_item(uma_zone_t, void *, void *, enum zfreeskip);
318 static int zone_alloc_limit(uma_zone_t zone, int count, int flags);
319 static void zone_free_limit(uma_zone_t zone, int count);
320 static void bucket_enable(void);
321 static void bucket_init(void);
322 static uma_bucket_t bucket_alloc(uma_zone_t zone, void *, int);
323 static void bucket_free(uma_zone_t zone, uma_bucket_t, void *);
324 static void bucket_zone_drain(int domain);
325 static uma_bucket_t zone_alloc_bucket(uma_zone_t, void *, int, int);
326 static void *slab_alloc_item(uma_keg_t keg, uma_slab_t slab);
327 static void slab_free_item(uma_zone_t zone, uma_slab_t slab, void *item);
328 static size_t slab_sizeof(int nitems);
329 static uma_keg_t uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit,
330     uma_fini fini, int align, uint32_t flags);
331 static int zone_import(void *, void **, int, int, int);
332 static void zone_release(void *, void **, int);
333 static bool cache_alloc(uma_zone_t, uma_cache_t, void *, int);
334 static bool cache_free(uma_zone_t, uma_cache_t, void *, int);
335 
336 static int sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS);
337 static int sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS);
338 static int sysctl_handle_uma_zone_allocs(SYSCTL_HANDLER_ARGS);
339 static int sysctl_handle_uma_zone_frees(SYSCTL_HANDLER_ARGS);
340 static int sysctl_handle_uma_zone_flags(SYSCTL_HANDLER_ARGS);
341 static int sysctl_handle_uma_slab_efficiency(SYSCTL_HANDLER_ARGS);
342 static int sysctl_handle_uma_zone_items(SYSCTL_HANDLER_ARGS);
343 
344 static uint64_t uma_zone_get_allocs(uma_zone_t zone);
345 
346 static SYSCTL_NODE(_vm, OID_AUTO, debug, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
347     "Memory allocation debugging");
348 
349 #ifdef INVARIANTS
350 static uint64_t uma_keg_get_allocs(uma_keg_t zone);
351 static inline struct noslabbits *slab_dbg_bits(uma_slab_t slab, uma_keg_t keg);
352 
353 static bool uma_dbg_kskip(uma_keg_t keg, void *mem);
354 static bool uma_dbg_zskip(uma_zone_t zone, void *mem);
355 static void uma_dbg_free(uma_zone_t zone, uma_slab_t slab, void *item);
356 static void uma_dbg_alloc(uma_zone_t zone, uma_slab_t slab, void *item);
357 
358 static u_int dbg_divisor = 1;
359 SYSCTL_UINT(_vm_debug, OID_AUTO, divisor,
360     CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &dbg_divisor, 0,
361     "Debug & thrash every this item in memory allocator");
362 
363 static counter_u64_t uma_dbg_cnt = EARLY_COUNTER;
364 static counter_u64_t uma_skip_cnt = EARLY_COUNTER;
365 SYSCTL_COUNTER_U64(_vm_debug, OID_AUTO, trashed, CTLFLAG_RD,
366     &uma_dbg_cnt, "memory items debugged");
367 SYSCTL_COUNTER_U64(_vm_debug, OID_AUTO, skipped, CTLFLAG_RD,
368     &uma_skip_cnt, "memory items skipped, not debugged");
369 #endif
370 
371 SYSCTL_NODE(_vm, OID_AUTO, uma, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
372     "Universal Memory Allocator");
373 
374 SYSCTL_PROC(_vm, OID_AUTO, zone_count, CTLFLAG_RD|CTLFLAG_MPSAFE|CTLTYPE_INT,
375     0, 0, sysctl_vm_zone_count, "I", "Number of UMA zones");
376 
377 SYSCTL_PROC(_vm, OID_AUTO, zone_stats, CTLFLAG_RD|CTLFLAG_MPSAFE|CTLTYPE_STRUCT,
378     0, 0, sysctl_vm_zone_stats, "s,struct uma_type_header", "Zone Stats");
379 
380 static int zone_warnings = 1;
381 SYSCTL_INT(_vm, OID_AUTO, zone_warnings, CTLFLAG_RWTUN, &zone_warnings, 0,
382     "Warn when UMA zones becomes full");
383 
384 static int multipage_slabs = 1;
385 TUNABLE_INT("vm.debug.uma_multipage_slabs", &multipage_slabs);
386 SYSCTL_INT(_vm_debug, OID_AUTO, uma_multipage_slabs,
387     CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &multipage_slabs, 0,
388     "UMA may choose larger slab sizes for better efficiency");
389 
390 /*
391  * Select the slab zone for an offpage slab with the given maximum item count.
392  */
393 static inline uma_zone_t
394 slabzone(int ipers)
395 {
396 
397 	return (slabzones[ipers > SLABZONE0_SETSIZE]);
398 }
399 
400 /*
401  * This routine checks to see whether or not it's safe to enable buckets.
402  */
403 static void
404 bucket_enable(void)
405 {
406 
407 	KASSERT(booted >= BOOT_KVA, ("Bucket enable before init"));
408 	bucketdisable = vm_page_count_min();
409 }
410 
411 /*
412  * Initialize bucket_zones, the array of zones of buckets of various sizes.
413  *
414  * For each zone, calculate the memory required for each bucket, consisting
415  * of the header and an array of pointers.
416  */
417 static void
418 bucket_init(void)
419 {
420 	struct uma_bucket_zone *ubz;
421 	int size;
422 
423 	for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++) {
424 		size = roundup(sizeof(struct uma_bucket), sizeof(void *));
425 		size += sizeof(void *) * ubz->ubz_entries;
426 		ubz->ubz_zone = uma_zcreate(ubz->ubz_name, size,
427 		    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR,
428 		    UMA_ZONE_MTXCLASS | UMA_ZFLAG_BUCKET |
429 		    UMA_ZONE_FIRSTTOUCH);
430 	}
431 }
432 
433 /*
434  * Given a desired number of entries for a bucket, return the zone from which
435  * to allocate the bucket.
436  */
437 static struct uma_bucket_zone *
438 bucket_zone_lookup(int entries)
439 {
440 	struct uma_bucket_zone *ubz;
441 
442 	for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++)
443 		if (ubz->ubz_entries >= entries)
444 			return (ubz);
445 	ubz--;
446 	return (ubz);
447 }
448 
449 static int
450 bucket_select(int size)
451 {
452 	struct uma_bucket_zone *ubz;
453 
454 	ubz = &bucket_zones[0];
455 	if (size > ubz->ubz_maxsize)
456 		return MAX((ubz->ubz_maxsize * ubz->ubz_entries) / size, 1);
457 
458 	for (; ubz->ubz_entries != 0; ubz++)
459 		if (ubz->ubz_maxsize < size)
460 			break;
461 	ubz--;
462 	return (ubz->ubz_entries);
463 }
464 
465 static uma_bucket_t
466 bucket_alloc(uma_zone_t zone, void *udata, int flags)
467 {
468 	struct uma_bucket_zone *ubz;
469 	uma_bucket_t bucket;
470 
471 	/*
472 	 * Don't allocate buckets early in boot.
473 	 */
474 	if (__predict_false(booted < BOOT_KVA))
475 		return (NULL);
476 
477 	/*
478 	 * To limit bucket recursion we store the original zone flags
479 	 * in a cookie passed via zalloc_arg/zfree_arg.  This allows the
480 	 * NOVM flag to persist even through deep recursions.  We also
481 	 * store ZFLAG_BUCKET once we have recursed attempting to allocate
482 	 * a bucket for a bucket zone so we do not allow infinite bucket
483 	 * recursion.  This cookie will even persist to frees of unused
484 	 * buckets via the allocation path or bucket allocations in the
485 	 * free path.
486 	 */
487 	if ((zone->uz_flags & UMA_ZFLAG_BUCKET) == 0)
488 		udata = (void *)(uintptr_t)zone->uz_flags;
489 	else {
490 		if ((uintptr_t)udata & UMA_ZFLAG_BUCKET)
491 			return (NULL);
492 		udata = (void *)((uintptr_t)udata | UMA_ZFLAG_BUCKET);
493 	}
494 	if (((uintptr_t)udata & UMA_ZONE_VM) != 0)
495 		flags |= M_NOVM;
496 	ubz = bucket_zone_lookup(atomic_load_16(&zone->uz_bucket_size));
497 	if (ubz->ubz_zone == zone && (ubz + 1)->ubz_entries != 0)
498 		ubz++;
499 	bucket = uma_zalloc_arg(ubz->ubz_zone, udata, flags);
500 	if (bucket) {
501 #ifdef INVARIANTS
502 		bzero(bucket->ub_bucket, sizeof(void *) * ubz->ubz_entries);
503 #endif
504 		bucket->ub_cnt = 0;
505 		bucket->ub_entries = min(ubz->ubz_entries,
506 		    zone->uz_bucket_size_max);
507 		bucket->ub_seq = SMR_SEQ_INVALID;
508 		CTR3(KTR_UMA, "bucket_alloc: zone %s(%p) allocated bucket %p",
509 		    zone->uz_name, zone, bucket);
510 	}
511 
512 	return (bucket);
513 }
514 
515 static void
516 bucket_free(uma_zone_t zone, uma_bucket_t bucket, void *udata)
517 {
518 	struct uma_bucket_zone *ubz;
519 
520 	if (bucket->ub_cnt != 0)
521 		bucket_drain(zone, bucket);
522 
523 	KASSERT(bucket->ub_cnt == 0,
524 	    ("bucket_free: Freeing a non free bucket."));
525 	KASSERT(bucket->ub_seq == SMR_SEQ_INVALID,
526 	    ("bucket_free: Freeing an SMR bucket."));
527 	if ((zone->uz_flags & UMA_ZFLAG_BUCKET) == 0)
528 		udata = (void *)(uintptr_t)zone->uz_flags;
529 	ubz = bucket_zone_lookup(bucket->ub_entries);
530 	uma_zfree_arg(ubz->ubz_zone, bucket, udata);
531 }
532 
533 static void
534 bucket_zone_drain(int domain)
535 {
536 	struct uma_bucket_zone *ubz;
537 
538 	for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++)
539 		uma_zone_reclaim_domain(ubz->ubz_zone, UMA_RECLAIM_DRAIN,
540 		    domain);
541 }
542 
543 #ifdef KASAN
544 _Static_assert(UMA_SMALLEST_UNIT % KASAN_SHADOW_SCALE == 0,
545     "Base UMA allocation size not a multiple of the KASAN scale factor");
546 
547 static void
548 kasan_mark_item_valid(uma_zone_t zone, void *item)
549 {
550 	void *pcpu_item;
551 	size_t sz, rsz;
552 	int i;
553 
554 	if ((zone->uz_flags & UMA_ZONE_NOKASAN) != 0)
555 		return;
556 
557 	sz = zone->uz_size;
558 	rsz = roundup2(sz, KASAN_SHADOW_SCALE);
559 	if ((zone->uz_flags & UMA_ZONE_PCPU) == 0) {
560 		kasan_mark(item, sz, rsz, KASAN_GENERIC_REDZONE);
561 	} else {
562 		pcpu_item = zpcpu_base_to_offset(item);
563 		for (i = 0; i <= mp_maxid; i++)
564 			kasan_mark(zpcpu_get_cpu(pcpu_item, i), sz, rsz,
565 			    KASAN_GENERIC_REDZONE);
566 	}
567 }
568 
569 static void
570 kasan_mark_item_invalid(uma_zone_t zone, void *item)
571 {
572 	void *pcpu_item;
573 	size_t sz;
574 	int i;
575 
576 	if ((zone->uz_flags & UMA_ZONE_NOKASAN) != 0)
577 		return;
578 
579 	sz = roundup2(zone->uz_size, KASAN_SHADOW_SCALE);
580 	if ((zone->uz_flags & UMA_ZONE_PCPU) == 0) {
581 		kasan_mark(item, 0, sz, KASAN_UMA_FREED);
582 	} else {
583 		pcpu_item = zpcpu_base_to_offset(item);
584 		for (i = 0; i <= mp_maxid; i++)
585 			kasan_mark(zpcpu_get_cpu(pcpu_item, i), 0, sz,
586 			    KASAN_UMA_FREED);
587 	}
588 }
589 
590 static void
591 kasan_mark_slab_valid(uma_keg_t keg, void *mem)
592 {
593 	size_t sz;
594 
595 	if ((keg->uk_flags & UMA_ZONE_NOKASAN) == 0) {
596 		sz = keg->uk_ppera * PAGE_SIZE;
597 		kasan_mark(mem, sz, sz, 0);
598 	}
599 }
600 
601 static void
602 kasan_mark_slab_invalid(uma_keg_t keg, void *mem)
603 {
604 	size_t sz;
605 
606 	if ((keg->uk_flags & UMA_ZONE_NOKASAN) == 0) {
607 		if ((keg->uk_flags & UMA_ZFLAG_OFFPAGE) != 0)
608 			sz = keg->uk_ppera * PAGE_SIZE;
609 		else
610 			sz = keg->uk_pgoff;
611 		kasan_mark(mem, 0, sz, KASAN_UMA_FREED);
612 	}
613 }
614 #else /* !KASAN */
615 static void
616 kasan_mark_item_valid(uma_zone_t zone __unused, void *item __unused)
617 {
618 }
619 
620 static void
621 kasan_mark_item_invalid(uma_zone_t zone __unused, void *item __unused)
622 {
623 }
624 
625 static void
626 kasan_mark_slab_valid(uma_keg_t keg __unused, void *mem __unused)
627 {
628 }
629 
630 static void
631 kasan_mark_slab_invalid(uma_keg_t keg __unused, void *mem __unused)
632 {
633 }
634 #endif /* KASAN */
635 
636 #ifdef KMSAN
637 static inline void
638 kmsan_mark_item_uninitialized(uma_zone_t zone, void *item)
639 {
640 	void *pcpu_item;
641 	size_t sz;
642 	int i;
643 
644 	if ((zone->uz_flags &
645 	    (UMA_ZFLAG_CACHE | UMA_ZONE_SECONDARY | UMA_ZONE_MALLOC)) != 0) {
646 		/*
647 		 * Cache zones should not be instrumented by default, as UMA
648 		 * does not have enough information to do so correctly.
649 		 * Consumers can mark items themselves if it makes sense to do
650 		 * so.
651 		 *
652 		 * Items from secondary zones are initialized by the parent
653 		 * zone and thus cannot safely be marked by UMA.
654 		 *
655 		 * malloc zones are handled directly by malloc(9) and friends,
656 		 * since they can provide more precise origin tracking.
657 		 */
658 		return;
659 	}
660 	if (zone->uz_keg->uk_init != NULL) {
661 		/*
662 		 * By definition, initialized items cannot be marked.  The
663 		 * best we can do is mark items from these zones after they
664 		 * are freed to the keg.
665 		 */
666 		return;
667 	}
668 
669 	sz = zone->uz_size;
670 	if ((zone->uz_flags & UMA_ZONE_PCPU) == 0) {
671 		kmsan_orig(item, sz, KMSAN_TYPE_UMA, KMSAN_RET_ADDR);
672 		kmsan_mark(item, sz, KMSAN_STATE_UNINIT);
673 	} else {
674 		pcpu_item = zpcpu_base_to_offset(item);
675 		for (i = 0; i <= mp_maxid; i++) {
676 			kmsan_orig(zpcpu_get_cpu(pcpu_item, i), sz,
677 			    KMSAN_TYPE_UMA, KMSAN_RET_ADDR);
678 			kmsan_mark(zpcpu_get_cpu(pcpu_item, i), sz,
679 			    KMSAN_STATE_INITED);
680 		}
681 	}
682 }
683 #else /* !KMSAN */
684 static inline void
685 kmsan_mark_item_uninitialized(uma_zone_t zone __unused, void *item __unused)
686 {
687 }
688 #endif /* KMSAN */
689 
690 /*
691  * Acquire the domain lock and record contention.
692  */
693 static uma_zone_domain_t
694 zone_domain_lock(uma_zone_t zone, int domain)
695 {
696 	uma_zone_domain_t zdom;
697 	bool lockfail;
698 
699 	zdom = ZDOM_GET(zone, domain);
700 	lockfail = false;
701 	if (ZDOM_OWNED(zdom))
702 		lockfail = true;
703 	ZDOM_LOCK(zdom);
704 	/* This is unsynchronized.  The counter does not need to be precise. */
705 	if (lockfail && zone->uz_bucket_size < zone->uz_bucket_size_max)
706 		zone->uz_bucket_size++;
707 	return (zdom);
708 }
709 
710 /*
711  * Search for the domain with the least cached items and return it if it
712  * is out of balance with the preferred domain.
713  */
714 static __noinline int
715 zone_domain_lowest(uma_zone_t zone, int pref)
716 {
717 	long least, nitems, prefitems;
718 	int domain;
719 	int i;
720 
721 	prefitems = least = LONG_MAX;
722 	domain = 0;
723 	for (i = 0; i < vm_ndomains; i++) {
724 		nitems = ZDOM_GET(zone, i)->uzd_nitems;
725 		if (nitems < least) {
726 			domain = i;
727 			least = nitems;
728 		}
729 		if (domain == pref)
730 			prefitems = nitems;
731 	}
732 	if (prefitems < least * 2)
733 		return (pref);
734 
735 	return (domain);
736 }
737 
738 /*
739  * Search for the domain with the most cached items and return it or the
740  * preferred domain if it has enough to proceed.
741  */
742 static __noinline int
743 zone_domain_highest(uma_zone_t zone, int pref)
744 {
745 	long most, nitems;
746 	int domain;
747 	int i;
748 
749 	if (ZDOM_GET(zone, pref)->uzd_nitems > BUCKET_MAX)
750 		return (pref);
751 
752 	most = 0;
753 	domain = 0;
754 	for (i = 0; i < vm_ndomains; i++) {
755 		nitems = ZDOM_GET(zone, i)->uzd_nitems;
756 		if (nitems > most) {
757 			domain = i;
758 			most = nitems;
759 		}
760 	}
761 
762 	return (domain);
763 }
764 
765 /*
766  * Set the maximum imax value.
767  */
768 static void
769 zone_domain_imax_set(uma_zone_domain_t zdom, int nitems)
770 {
771 	long old;
772 
773 	old = zdom->uzd_imax;
774 	do {
775 		if (old >= nitems)
776 			return;
777 	} while (atomic_fcmpset_long(&zdom->uzd_imax, &old, nitems) == 0);
778 
779 	/*
780 	 * We are at new maximum, so do the last WSS update for the old
781 	 * bimin and prepare to measure next allocation batch.
782 	 */
783 	if (zdom->uzd_wss < old - zdom->uzd_bimin)
784 		zdom->uzd_wss = old - zdom->uzd_bimin;
785 	zdom->uzd_bimin = nitems;
786 }
787 
788 /*
789  * Attempt to satisfy an allocation by retrieving a full bucket from one of the
790  * zone's caches.  If a bucket is found the zone is not locked on return.
791  */
792 static uma_bucket_t
793 zone_fetch_bucket(uma_zone_t zone, uma_zone_domain_t zdom, bool reclaim)
794 {
795 	uma_bucket_t bucket;
796 	long cnt;
797 	int i;
798 	bool dtor = false;
799 
800 	ZDOM_LOCK_ASSERT(zdom);
801 
802 	if ((bucket = STAILQ_FIRST(&zdom->uzd_buckets)) == NULL)
803 		return (NULL);
804 
805 	/* SMR Buckets can not be re-used until readers expire. */
806 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0 &&
807 	    bucket->ub_seq != SMR_SEQ_INVALID) {
808 		if (!smr_poll(zone->uz_smr, bucket->ub_seq, false))
809 			return (NULL);
810 		bucket->ub_seq = SMR_SEQ_INVALID;
811 		dtor = (zone->uz_dtor != NULL) || UMA_ALWAYS_CTORDTOR;
812 		if (STAILQ_NEXT(bucket, ub_link) != NULL)
813 			zdom->uzd_seq = STAILQ_NEXT(bucket, ub_link)->ub_seq;
814 	}
815 	STAILQ_REMOVE_HEAD(&zdom->uzd_buckets, ub_link);
816 
817 	KASSERT(zdom->uzd_nitems >= bucket->ub_cnt,
818 	    ("%s: item count underflow (%ld, %d)",
819 	    __func__, zdom->uzd_nitems, bucket->ub_cnt));
820 	KASSERT(bucket->ub_cnt > 0,
821 	    ("%s: empty bucket in bucket cache", __func__));
822 	zdom->uzd_nitems -= bucket->ub_cnt;
823 
824 	if (reclaim) {
825 		/*
826 		 * Shift the bounds of the current WSS interval to avoid
827 		 * perturbing the estimates.
828 		 */
829 		cnt = lmin(zdom->uzd_bimin, bucket->ub_cnt);
830 		atomic_subtract_long(&zdom->uzd_imax, cnt);
831 		zdom->uzd_bimin -= cnt;
832 		zdom->uzd_imin -= lmin(zdom->uzd_imin, bucket->ub_cnt);
833 		if (zdom->uzd_limin >= bucket->ub_cnt) {
834 			zdom->uzd_limin -= bucket->ub_cnt;
835 		} else {
836 			zdom->uzd_limin = 0;
837 			zdom->uzd_timin = 0;
838 		}
839 	} else if (zdom->uzd_bimin > zdom->uzd_nitems) {
840 		zdom->uzd_bimin = zdom->uzd_nitems;
841 		if (zdom->uzd_imin > zdom->uzd_nitems)
842 			zdom->uzd_imin = zdom->uzd_nitems;
843 	}
844 
845 	ZDOM_UNLOCK(zdom);
846 	if (dtor)
847 		for (i = 0; i < bucket->ub_cnt; i++)
848 			item_dtor(zone, bucket->ub_bucket[i], zone->uz_size,
849 			    NULL, SKIP_NONE);
850 
851 	return (bucket);
852 }
853 
854 /*
855  * Insert a full bucket into the specified cache.  The "ws" parameter indicates
856  * whether the bucket's contents should be counted as part of the zone's working
857  * set.  The bucket may be freed if it exceeds the bucket limit.
858  */
859 static void
860 zone_put_bucket(uma_zone_t zone, int domain, uma_bucket_t bucket, void *udata,
861     const bool ws)
862 {
863 	uma_zone_domain_t zdom;
864 
865 	/* We don't cache empty buckets.  This can happen after a reclaim. */
866 	if (bucket->ub_cnt == 0)
867 		goto out;
868 	zdom = zone_domain_lock(zone, domain);
869 
870 	/*
871 	 * Conditionally set the maximum number of items.
872 	 */
873 	zdom->uzd_nitems += bucket->ub_cnt;
874 	if (__predict_true(zdom->uzd_nitems < zone->uz_bucket_max)) {
875 		if (ws) {
876 			zone_domain_imax_set(zdom, zdom->uzd_nitems);
877 		} else {
878 			/*
879 			 * Shift the bounds of the current WSS interval to
880 			 * avoid perturbing the estimates.
881 			 */
882 			atomic_add_long(&zdom->uzd_imax, bucket->ub_cnt);
883 			zdom->uzd_imin += bucket->ub_cnt;
884 			zdom->uzd_bimin += bucket->ub_cnt;
885 			zdom->uzd_limin += bucket->ub_cnt;
886 		}
887 		if (STAILQ_EMPTY(&zdom->uzd_buckets))
888 			zdom->uzd_seq = bucket->ub_seq;
889 
890 		/*
891 		 * Try to promote reuse of recently used items.  For items
892 		 * protected by SMR, try to defer reuse to minimize polling.
893 		 */
894 		if (bucket->ub_seq == SMR_SEQ_INVALID)
895 			STAILQ_INSERT_HEAD(&zdom->uzd_buckets, bucket, ub_link);
896 		else
897 			STAILQ_INSERT_TAIL(&zdom->uzd_buckets, bucket, ub_link);
898 		ZDOM_UNLOCK(zdom);
899 		return;
900 	}
901 	zdom->uzd_nitems -= bucket->ub_cnt;
902 	ZDOM_UNLOCK(zdom);
903 out:
904 	bucket_free(zone, bucket, udata);
905 }
906 
907 /* Pops an item out of a per-cpu cache bucket. */
908 static inline void *
909 cache_bucket_pop(uma_cache_t cache, uma_cache_bucket_t bucket)
910 {
911 	void *item;
912 
913 	CRITICAL_ASSERT(curthread);
914 
915 	bucket->ucb_cnt--;
916 	item = bucket->ucb_bucket->ub_bucket[bucket->ucb_cnt];
917 #ifdef INVARIANTS
918 	bucket->ucb_bucket->ub_bucket[bucket->ucb_cnt] = NULL;
919 	KASSERT(item != NULL, ("uma_zalloc: Bucket pointer mangled."));
920 #endif
921 	cache->uc_allocs++;
922 
923 	return (item);
924 }
925 
926 /* Pushes an item into a per-cpu cache bucket. */
927 static inline void
928 cache_bucket_push(uma_cache_t cache, uma_cache_bucket_t bucket, void *item)
929 {
930 
931 	CRITICAL_ASSERT(curthread);
932 	KASSERT(bucket->ucb_bucket->ub_bucket[bucket->ucb_cnt] == NULL,
933 	    ("uma_zfree: Freeing to non free bucket index."));
934 
935 	bucket->ucb_bucket->ub_bucket[bucket->ucb_cnt] = item;
936 	bucket->ucb_cnt++;
937 	cache->uc_frees++;
938 }
939 
940 /*
941  * Unload a UMA bucket from a per-cpu cache.
942  */
943 static inline uma_bucket_t
944 cache_bucket_unload(uma_cache_bucket_t bucket)
945 {
946 	uma_bucket_t b;
947 
948 	b = bucket->ucb_bucket;
949 	if (b != NULL) {
950 		MPASS(b->ub_entries == bucket->ucb_entries);
951 		b->ub_cnt = bucket->ucb_cnt;
952 		bucket->ucb_bucket = NULL;
953 		bucket->ucb_entries = bucket->ucb_cnt = 0;
954 	}
955 
956 	return (b);
957 }
958 
959 static inline uma_bucket_t
960 cache_bucket_unload_alloc(uma_cache_t cache)
961 {
962 
963 	return (cache_bucket_unload(&cache->uc_allocbucket));
964 }
965 
966 static inline uma_bucket_t
967 cache_bucket_unload_free(uma_cache_t cache)
968 {
969 
970 	return (cache_bucket_unload(&cache->uc_freebucket));
971 }
972 
973 static inline uma_bucket_t
974 cache_bucket_unload_cross(uma_cache_t cache)
975 {
976 
977 	return (cache_bucket_unload(&cache->uc_crossbucket));
978 }
979 
980 /*
981  * Load a bucket into a per-cpu cache bucket.
982  */
983 static inline void
984 cache_bucket_load(uma_cache_bucket_t bucket, uma_bucket_t b)
985 {
986 
987 	CRITICAL_ASSERT(curthread);
988 	MPASS(bucket->ucb_bucket == NULL);
989 	MPASS(b->ub_seq == SMR_SEQ_INVALID);
990 
991 	bucket->ucb_bucket = b;
992 	bucket->ucb_cnt = b->ub_cnt;
993 	bucket->ucb_entries = b->ub_entries;
994 }
995 
996 static inline void
997 cache_bucket_load_alloc(uma_cache_t cache, uma_bucket_t b)
998 {
999 
1000 	cache_bucket_load(&cache->uc_allocbucket, b);
1001 }
1002 
1003 static inline void
1004 cache_bucket_load_free(uma_cache_t cache, uma_bucket_t b)
1005 {
1006 
1007 	cache_bucket_load(&cache->uc_freebucket, b);
1008 }
1009 
1010 #ifdef NUMA
1011 static inline void
1012 cache_bucket_load_cross(uma_cache_t cache, uma_bucket_t b)
1013 {
1014 
1015 	cache_bucket_load(&cache->uc_crossbucket, b);
1016 }
1017 #endif
1018 
1019 /*
1020  * Copy and preserve ucb_spare.
1021  */
1022 static inline void
1023 cache_bucket_copy(uma_cache_bucket_t b1, uma_cache_bucket_t b2)
1024 {
1025 
1026 	b1->ucb_bucket = b2->ucb_bucket;
1027 	b1->ucb_entries = b2->ucb_entries;
1028 	b1->ucb_cnt = b2->ucb_cnt;
1029 }
1030 
1031 /*
1032  * Swap two cache buckets.
1033  */
1034 static inline void
1035 cache_bucket_swap(uma_cache_bucket_t b1, uma_cache_bucket_t b2)
1036 {
1037 	struct uma_cache_bucket b3;
1038 
1039 	CRITICAL_ASSERT(curthread);
1040 
1041 	cache_bucket_copy(&b3, b1);
1042 	cache_bucket_copy(b1, b2);
1043 	cache_bucket_copy(b2, &b3);
1044 }
1045 
1046 /*
1047  * Attempt to fetch a bucket from a zone on behalf of the current cpu cache.
1048  */
1049 static uma_bucket_t
1050 cache_fetch_bucket(uma_zone_t zone, uma_cache_t cache, int domain)
1051 {
1052 	uma_zone_domain_t zdom;
1053 	uma_bucket_t bucket;
1054 	smr_seq_t seq;
1055 
1056 	/*
1057 	 * Avoid the lock if possible.
1058 	 */
1059 	zdom = ZDOM_GET(zone, domain);
1060 	if (zdom->uzd_nitems == 0)
1061 		return (NULL);
1062 
1063 	if ((cache_uz_flags(cache) & UMA_ZONE_SMR) != 0 &&
1064 	    (seq = atomic_load_32(&zdom->uzd_seq)) != SMR_SEQ_INVALID &&
1065 	    !smr_poll(zone->uz_smr, seq, false))
1066 		return (NULL);
1067 
1068 	/*
1069 	 * Check the zone's cache of buckets.
1070 	 */
1071 	zdom = zone_domain_lock(zone, domain);
1072 	if ((bucket = zone_fetch_bucket(zone, zdom, false)) != NULL)
1073 		return (bucket);
1074 	ZDOM_UNLOCK(zdom);
1075 
1076 	return (NULL);
1077 }
1078 
1079 static void
1080 zone_log_warning(uma_zone_t zone)
1081 {
1082 	static const struct timeval warninterval = { 300, 0 };
1083 
1084 	if (!zone_warnings || zone->uz_warning == NULL)
1085 		return;
1086 
1087 	if (ratecheck(&zone->uz_ratecheck, &warninterval))
1088 		printf("[zone: %s] %s\n", zone->uz_name, zone->uz_warning);
1089 }
1090 
1091 static inline void
1092 zone_maxaction(uma_zone_t zone)
1093 {
1094 
1095 	if (zone->uz_maxaction.ta_func != NULL)
1096 		taskqueue_enqueue(taskqueue_thread, &zone->uz_maxaction);
1097 }
1098 
1099 /*
1100  * Routine called by timeout which is used to fire off some time interval
1101  * based calculations.  (stats, hash size, etc.)
1102  *
1103  * Arguments:
1104  *	arg   Unused
1105  *
1106  * Returns:
1107  *	Nothing
1108  */
1109 static void
1110 uma_timeout(void *context __unused, int pending __unused)
1111 {
1112 	bucket_enable();
1113 	zone_foreach(zone_timeout, NULL);
1114 
1115 	/* Reschedule this event */
1116 	taskqueue_enqueue_timeout(taskqueue_thread, &uma_timeout_task,
1117 	    UMA_TIMEOUT * hz);
1118 }
1119 
1120 /*
1121  * Update the working set size estimates for the zone's bucket cache.
1122  * The constants chosen here are somewhat arbitrary.
1123  */
1124 static void
1125 zone_domain_update_wss(uma_zone_domain_t zdom)
1126 {
1127 	long m;
1128 
1129 	ZDOM_LOCK_ASSERT(zdom);
1130 	MPASS(zdom->uzd_imax >= zdom->uzd_nitems);
1131 	MPASS(zdom->uzd_nitems >= zdom->uzd_bimin);
1132 	MPASS(zdom->uzd_bimin >= zdom->uzd_imin);
1133 
1134 	/*
1135 	 * Estimate WSS as modified moving average of biggest allocation
1136 	 * batches for each period over few minutes (UMA_TIMEOUT of 20s).
1137 	 */
1138 	zdom->uzd_wss = lmax(zdom->uzd_wss * 3 / 4,
1139 	    zdom->uzd_imax - zdom->uzd_bimin);
1140 
1141 	/*
1142 	 * Estimate longtime minimum item count as a combination of recent
1143 	 * minimum item count, adjusted by WSS for safety, and the modified
1144 	 * moving average over the last several hours (UMA_TIMEOUT of 20s).
1145 	 * timin measures time since limin tried to go negative, that means
1146 	 * we were dangerously close to or got out of cache.
1147 	 */
1148 	m = zdom->uzd_imin - zdom->uzd_wss;
1149 	if (m >= 0) {
1150 		if (zdom->uzd_limin >= m)
1151 			zdom->uzd_limin = m;
1152 		else
1153 			zdom->uzd_limin = (m + zdom->uzd_limin * 255) / 256;
1154 		zdom->uzd_timin++;
1155 	} else {
1156 		zdom->uzd_limin = 0;
1157 		zdom->uzd_timin = 0;
1158 	}
1159 
1160 	/* To reduce period edge effects on WSS keep half of the imax. */
1161 	atomic_subtract_long(&zdom->uzd_imax,
1162 	    (zdom->uzd_imax - zdom->uzd_nitems + 1) / 2);
1163 	zdom->uzd_imin = zdom->uzd_bimin = zdom->uzd_nitems;
1164 }
1165 
1166 /*
1167  * Routine to perform timeout driven calculations.  This expands the
1168  * hashes and does per cpu statistics aggregation.
1169  *
1170  *  Returns nothing.
1171  */
1172 static void
1173 zone_timeout(uma_zone_t zone, void *unused)
1174 {
1175 	uma_keg_t keg;
1176 	u_int slabs, pages;
1177 
1178 	if ((zone->uz_flags & UMA_ZFLAG_HASH) == 0)
1179 		goto trim;
1180 
1181 	keg = zone->uz_keg;
1182 
1183 	/*
1184 	 * Hash zones are non-numa by definition so the first domain
1185 	 * is the only one present.
1186 	 */
1187 	KEG_LOCK(keg, 0);
1188 	pages = keg->uk_domain[0].ud_pages;
1189 
1190 	/*
1191 	 * Expand the keg hash table.
1192 	 *
1193 	 * This is done if the number of slabs is larger than the hash size.
1194 	 * What I'm trying to do here is completely reduce collisions.  This
1195 	 * may be a little aggressive.  Should I allow for two collisions max?
1196 	 */
1197 	if ((slabs = pages / keg->uk_ppera) > keg->uk_hash.uh_hashsize) {
1198 		struct uma_hash newhash;
1199 		struct uma_hash oldhash;
1200 		int ret;
1201 
1202 		/*
1203 		 * This is so involved because allocating and freeing
1204 		 * while the keg lock is held will lead to deadlock.
1205 		 * I have to do everything in stages and check for
1206 		 * races.
1207 		 */
1208 		KEG_UNLOCK(keg, 0);
1209 		ret = hash_alloc(&newhash, 1 << fls(slabs));
1210 		KEG_LOCK(keg, 0);
1211 		if (ret) {
1212 			if (hash_expand(&keg->uk_hash, &newhash)) {
1213 				oldhash = keg->uk_hash;
1214 				keg->uk_hash = newhash;
1215 			} else
1216 				oldhash = newhash;
1217 
1218 			KEG_UNLOCK(keg, 0);
1219 			hash_free(&oldhash);
1220 			goto trim;
1221 		}
1222 	}
1223 	KEG_UNLOCK(keg, 0);
1224 
1225 trim:
1226 	/* Trim caches not used for a long time. */
1227 	if ((zone->uz_flags & UMA_ZONE_UNMANAGED) == 0) {
1228 		for (int i = 0; i < vm_ndomains; i++) {
1229 			if (bucket_cache_reclaim_domain(zone, false, false, i) &&
1230 			    (zone->uz_flags & UMA_ZFLAG_CACHE) == 0)
1231 				keg_drain(zone->uz_keg, i);
1232 		}
1233 	}
1234 }
1235 
1236 /*
1237  * Allocate and zero fill the next sized hash table from the appropriate
1238  * backing store.
1239  *
1240  * Arguments:
1241  *	hash  A new hash structure with the old hash size in uh_hashsize
1242  *
1243  * Returns:
1244  *	1 on success and 0 on failure.
1245  */
1246 static int
1247 hash_alloc(struct uma_hash *hash, u_int size)
1248 {
1249 	size_t alloc;
1250 
1251 	KASSERT(powerof2(size), ("hash size must be power of 2"));
1252 	if (size > UMA_HASH_SIZE_INIT)  {
1253 		hash->uh_hashsize = size;
1254 		alloc = sizeof(hash->uh_slab_hash[0]) * hash->uh_hashsize;
1255 		hash->uh_slab_hash = malloc(alloc, M_UMAHASH, M_NOWAIT);
1256 	} else {
1257 		alloc = sizeof(hash->uh_slab_hash[0]) * UMA_HASH_SIZE_INIT;
1258 		hash->uh_slab_hash = zone_alloc_item(hashzone, NULL,
1259 		    UMA_ANYDOMAIN, M_WAITOK);
1260 		hash->uh_hashsize = UMA_HASH_SIZE_INIT;
1261 	}
1262 	if (hash->uh_slab_hash) {
1263 		bzero(hash->uh_slab_hash, alloc);
1264 		hash->uh_hashmask = hash->uh_hashsize - 1;
1265 		return (1);
1266 	}
1267 
1268 	return (0);
1269 }
1270 
1271 /*
1272  * Expands the hash table for HASH zones.  This is done from zone_timeout
1273  * to reduce collisions.  This must not be done in the regular allocation
1274  * path, otherwise, we can recurse on the vm while allocating pages.
1275  *
1276  * Arguments:
1277  *	oldhash  The hash you want to expand
1278  *	newhash  The hash structure for the new table
1279  *
1280  * Returns:
1281  *	Nothing
1282  *
1283  * Discussion:
1284  */
1285 static int
1286 hash_expand(struct uma_hash *oldhash, struct uma_hash *newhash)
1287 {
1288 	uma_hash_slab_t slab;
1289 	u_int hval;
1290 	u_int idx;
1291 
1292 	if (!newhash->uh_slab_hash)
1293 		return (0);
1294 
1295 	if (oldhash->uh_hashsize >= newhash->uh_hashsize)
1296 		return (0);
1297 
1298 	/*
1299 	 * I need to investigate hash algorithms for resizing without a
1300 	 * full rehash.
1301 	 */
1302 
1303 	for (idx = 0; idx < oldhash->uh_hashsize; idx++)
1304 		while (!LIST_EMPTY(&oldhash->uh_slab_hash[idx])) {
1305 			slab = LIST_FIRST(&oldhash->uh_slab_hash[idx]);
1306 			LIST_REMOVE(slab, uhs_hlink);
1307 			hval = UMA_HASH(newhash, slab->uhs_data);
1308 			LIST_INSERT_HEAD(&newhash->uh_slab_hash[hval],
1309 			    slab, uhs_hlink);
1310 		}
1311 
1312 	return (1);
1313 }
1314 
1315 /*
1316  * Free the hash bucket to the appropriate backing store.
1317  *
1318  * Arguments:
1319  *	slab_hash  The hash bucket we're freeing
1320  *	hashsize   The number of entries in that hash bucket
1321  *
1322  * Returns:
1323  *	Nothing
1324  */
1325 static void
1326 hash_free(struct uma_hash *hash)
1327 {
1328 	if (hash->uh_slab_hash == NULL)
1329 		return;
1330 	if (hash->uh_hashsize == UMA_HASH_SIZE_INIT)
1331 		zone_free_item(hashzone, hash->uh_slab_hash, NULL, SKIP_NONE);
1332 	else
1333 		free(hash->uh_slab_hash, M_UMAHASH);
1334 }
1335 
1336 /*
1337  * Frees all outstanding items in a bucket
1338  *
1339  * Arguments:
1340  *	zone   The zone to free to, must be unlocked.
1341  *	bucket The free/alloc bucket with items.
1342  *
1343  * Returns:
1344  *	Nothing
1345  */
1346 static void
1347 bucket_drain(uma_zone_t zone, uma_bucket_t bucket)
1348 {
1349 	int i;
1350 
1351 	if (bucket->ub_cnt == 0)
1352 		return;
1353 
1354 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0 &&
1355 	    bucket->ub_seq != SMR_SEQ_INVALID) {
1356 		smr_wait(zone->uz_smr, bucket->ub_seq);
1357 		bucket->ub_seq = SMR_SEQ_INVALID;
1358 		for (i = 0; i < bucket->ub_cnt; i++)
1359 			item_dtor(zone, bucket->ub_bucket[i],
1360 			    zone->uz_size, NULL, SKIP_NONE);
1361 	}
1362 	if (zone->uz_fini)
1363 		for (i = 0; i < bucket->ub_cnt; i++) {
1364 			kasan_mark_item_valid(zone, bucket->ub_bucket[i]);
1365 			zone->uz_fini(bucket->ub_bucket[i], zone->uz_size);
1366 			kasan_mark_item_invalid(zone, bucket->ub_bucket[i]);
1367 		}
1368 	zone->uz_release(zone->uz_arg, bucket->ub_bucket, bucket->ub_cnt);
1369 	if (zone->uz_max_items > 0)
1370 		zone_free_limit(zone, bucket->ub_cnt);
1371 #ifdef INVARIANTS
1372 	bzero(bucket->ub_bucket, sizeof(void *) * bucket->ub_cnt);
1373 #endif
1374 	bucket->ub_cnt = 0;
1375 }
1376 
1377 /*
1378  * Drains the per cpu caches for a zone.
1379  *
1380  * NOTE: This may only be called while the zone is being torn down, and not
1381  * during normal operation.  This is necessary in order that we do not have
1382  * to migrate CPUs to drain the per-CPU caches.
1383  *
1384  * Arguments:
1385  *	zone     The zone to drain, must be unlocked.
1386  *
1387  * Returns:
1388  *	Nothing
1389  */
1390 static void
1391 cache_drain(uma_zone_t zone)
1392 {
1393 	uma_cache_t cache;
1394 	uma_bucket_t bucket;
1395 	smr_seq_t seq;
1396 	int cpu;
1397 
1398 	/*
1399 	 * XXX: It is safe to not lock the per-CPU caches, because we're
1400 	 * tearing down the zone anyway.  I.e., there will be no further use
1401 	 * of the caches at this point.
1402 	 *
1403 	 * XXX: It would good to be able to assert that the zone is being
1404 	 * torn down to prevent improper use of cache_drain().
1405 	 */
1406 	seq = SMR_SEQ_INVALID;
1407 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0)
1408 		seq = smr_advance(zone->uz_smr);
1409 	CPU_FOREACH(cpu) {
1410 		cache = &zone->uz_cpu[cpu];
1411 		bucket = cache_bucket_unload_alloc(cache);
1412 		if (bucket != NULL)
1413 			bucket_free(zone, bucket, NULL);
1414 		bucket = cache_bucket_unload_free(cache);
1415 		if (bucket != NULL) {
1416 			bucket->ub_seq = seq;
1417 			bucket_free(zone, bucket, NULL);
1418 		}
1419 		bucket = cache_bucket_unload_cross(cache);
1420 		if (bucket != NULL) {
1421 			bucket->ub_seq = seq;
1422 			bucket_free(zone, bucket, NULL);
1423 		}
1424 	}
1425 	bucket_cache_reclaim(zone, true, UMA_ANYDOMAIN);
1426 }
1427 
1428 static void
1429 cache_shrink(uma_zone_t zone, void *unused)
1430 {
1431 
1432 	if (zone->uz_flags & UMA_ZFLAG_INTERNAL)
1433 		return;
1434 
1435 	ZONE_LOCK(zone);
1436 	zone->uz_bucket_size =
1437 	    (zone->uz_bucket_size_min + zone->uz_bucket_size) / 2;
1438 	ZONE_UNLOCK(zone);
1439 }
1440 
1441 static void
1442 cache_drain_safe_cpu(uma_zone_t zone, void *unused)
1443 {
1444 	uma_cache_t cache;
1445 	uma_bucket_t b1, b2, b3;
1446 	int domain;
1447 
1448 	if (zone->uz_flags & UMA_ZFLAG_INTERNAL)
1449 		return;
1450 
1451 	b1 = b2 = b3 = NULL;
1452 	critical_enter();
1453 	cache = &zone->uz_cpu[curcpu];
1454 	domain = PCPU_GET(domain);
1455 	b1 = cache_bucket_unload_alloc(cache);
1456 
1457 	/*
1458 	 * Don't flush SMR zone buckets.  This leaves the zone without a
1459 	 * bucket and forces every free to synchronize().
1460 	 */
1461 	if ((zone->uz_flags & UMA_ZONE_SMR) == 0) {
1462 		b2 = cache_bucket_unload_free(cache);
1463 		b3 = cache_bucket_unload_cross(cache);
1464 	}
1465 	critical_exit();
1466 
1467 	if (b1 != NULL)
1468 		zone_free_bucket(zone, b1, NULL, domain, false);
1469 	if (b2 != NULL)
1470 		zone_free_bucket(zone, b2, NULL, domain, false);
1471 	if (b3 != NULL) {
1472 		/* Adjust the domain so it goes to zone_free_cross. */
1473 		domain = (domain + 1) % vm_ndomains;
1474 		zone_free_bucket(zone, b3, NULL, domain, false);
1475 	}
1476 }
1477 
1478 /*
1479  * Safely drain per-CPU caches of a zone(s) to alloc bucket.
1480  * This is an expensive call because it needs to bind to all CPUs
1481  * one by one and enter a critical section on each of them in order
1482  * to safely access their cache buckets.
1483  * Zone lock must not be held on call this function.
1484  */
1485 static void
1486 pcpu_cache_drain_safe(uma_zone_t zone)
1487 {
1488 	int cpu;
1489 
1490 	/*
1491 	 * Polite bucket sizes shrinking was not enough, shrink aggressively.
1492 	 */
1493 	if (zone)
1494 		cache_shrink(zone, NULL);
1495 	else
1496 		zone_foreach(cache_shrink, NULL);
1497 
1498 	CPU_FOREACH(cpu) {
1499 		thread_lock(curthread);
1500 		sched_bind(curthread, cpu);
1501 		thread_unlock(curthread);
1502 
1503 		if (zone)
1504 			cache_drain_safe_cpu(zone, NULL);
1505 		else
1506 			zone_foreach(cache_drain_safe_cpu, NULL);
1507 	}
1508 	thread_lock(curthread);
1509 	sched_unbind(curthread);
1510 	thread_unlock(curthread);
1511 }
1512 
1513 /*
1514  * Reclaim cached buckets from a zone.  All buckets are reclaimed if the caller
1515  * requested a drain, otherwise the per-domain caches are trimmed to either
1516  * estimated working set size.
1517  */
1518 static bool
1519 bucket_cache_reclaim_domain(uma_zone_t zone, bool drain, bool trim, int domain)
1520 {
1521 	uma_zone_domain_t zdom;
1522 	uma_bucket_t bucket;
1523 	long target;
1524 	bool done = false;
1525 
1526 	/*
1527 	 * The cross bucket is partially filled and not part of
1528 	 * the item count.  Reclaim it individually here.
1529 	 */
1530 	zdom = ZDOM_GET(zone, domain);
1531 	if ((zone->uz_flags & UMA_ZONE_SMR) == 0 || drain) {
1532 		ZONE_CROSS_LOCK(zone);
1533 		bucket = zdom->uzd_cross;
1534 		zdom->uzd_cross = NULL;
1535 		ZONE_CROSS_UNLOCK(zone);
1536 		if (bucket != NULL)
1537 			bucket_free(zone, bucket, NULL);
1538 	}
1539 
1540 	/*
1541 	 * If we were asked to drain the zone, we are done only once
1542 	 * this bucket cache is empty.  If trim, we reclaim items in
1543 	 * excess of the zone's estimated working set size.  Multiple
1544 	 * consecutive calls will shrink the WSS and so reclaim more.
1545 	 * If neither drain nor trim, then voluntarily reclaim 1/4
1546 	 * (to reduce first spike) of items not used for a long time.
1547 	 */
1548 	ZDOM_LOCK(zdom);
1549 	zone_domain_update_wss(zdom);
1550 	if (drain)
1551 		target = 0;
1552 	else if (trim)
1553 		target = zdom->uzd_wss;
1554 	else if (zdom->uzd_timin > 900 / UMA_TIMEOUT)
1555 		target = zdom->uzd_nitems - zdom->uzd_limin / 4;
1556 	else {
1557 		ZDOM_UNLOCK(zdom);
1558 		return (done);
1559 	}
1560 	while ((bucket = STAILQ_FIRST(&zdom->uzd_buckets)) != NULL &&
1561 	    zdom->uzd_nitems >= target + bucket->ub_cnt) {
1562 		bucket = zone_fetch_bucket(zone, zdom, true);
1563 		if (bucket == NULL)
1564 			break;
1565 		bucket_free(zone, bucket, NULL);
1566 		done = true;
1567 		ZDOM_LOCK(zdom);
1568 	}
1569 	ZDOM_UNLOCK(zdom);
1570 	return (done);
1571 }
1572 
1573 static void
1574 bucket_cache_reclaim(uma_zone_t zone, bool drain, int domain)
1575 {
1576 	int i;
1577 
1578 	/*
1579 	 * Shrink the zone bucket size to ensure that the per-CPU caches
1580 	 * don't grow too large.
1581 	 */
1582 	if (zone->uz_bucket_size > zone->uz_bucket_size_min)
1583 		zone->uz_bucket_size--;
1584 
1585 	if (domain != UMA_ANYDOMAIN &&
1586 	    (zone->uz_flags & UMA_ZONE_ROUNDROBIN) == 0) {
1587 		bucket_cache_reclaim_domain(zone, drain, true, domain);
1588 	} else {
1589 		for (i = 0; i < vm_ndomains; i++)
1590 			bucket_cache_reclaim_domain(zone, drain, true, i);
1591 	}
1592 }
1593 
1594 static void
1595 keg_free_slab(uma_keg_t keg, uma_slab_t slab, int start)
1596 {
1597 	uint8_t *mem;
1598 	size_t size;
1599 	int i;
1600 	uint8_t flags;
1601 
1602 	CTR4(KTR_UMA, "keg_free_slab keg %s(%p) slab %p, returning %d bytes",
1603 	    keg->uk_name, keg, slab, PAGE_SIZE * keg->uk_ppera);
1604 
1605 	mem = slab_data(slab, keg);
1606 	size = PAGE_SIZE * keg->uk_ppera;
1607 
1608 	kasan_mark_slab_valid(keg, mem);
1609 	if (keg->uk_fini != NULL) {
1610 		for (i = start - 1; i > -1; i--)
1611 #ifdef INVARIANTS
1612 		/*
1613 		 * trash_fini implies that dtor was trash_dtor. trash_fini
1614 		 * would check that memory hasn't been modified since free,
1615 		 * which executed trash_dtor.
1616 		 * That's why we need to run uma_dbg_kskip() check here,
1617 		 * albeit we don't make skip check for other init/fini
1618 		 * invocations.
1619 		 */
1620 		if (!uma_dbg_kskip(keg, slab_item(slab, keg, i)) ||
1621 		    keg->uk_fini != trash_fini)
1622 #endif
1623 			keg->uk_fini(slab_item(slab, keg, i), keg->uk_size);
1624 	}
1625 	flags = slab->us_flags;
1626 	if (keg->uk_flags & UMA_ZFLAG_OFFPAGE) {
1627 		zone_free_item(slabzone(keg->uk_ipers), slab_tohashslab(slab),
1628 		    NULL, SKIP_NONE);
1629 	}
1630 	keg->uk_freef(mem, size, flags);
1631 	uma_total_dec(size);
1632 }
1633 
1634 static void
1635 keg_drain_domain(uma_keg_t keg, int domain)
1636 {
1637 	struct slabhead freeslabs;
1638 	uma_domain_t dom;
1639 	uma_slab_t slab, tmp;
1640 	uint32_t i, stofree, stokeep, partial;
1641 
1642 	dom = &keg->uk_domain[domain];
1643 	LIST_INIT(&freeslabs);
1644 
1645 	CTR4(KTR_UMA, "keg_drain %s(%p) domain %d free items: %u",
1646 	    keg->uk_name, keg, domain, dom->ud_free_items);
1647 
1648 	KEG_LOCK(keg, domain);
1649 
1650 	/*
1651 	 * Are the free items in partially allocated slabs sufficient to meet
1652 	 * the reserve? If not, compute the number of fully free slabs that must
1653 	 * be kept.
1654 	 */
1655 	partial = dom->ud_free_items - dom->ud_free_slabs * keg->uk_ipers;
1656 	if (partial < keg->uk_reserve) {
1657 		stokeep = min(dom->ud_free_slabs,
1658 		    howmany(keg->uk_reserve - partial, keg->uk_ipers));
1659 	} else {
1660 		stokeep = 0;
1661 	}
1662 	stofree = dom->ud_free_slabs - stokeep;
1663 
1664 	/*
1665 	 * Partition the free slabs into two sets: those that must be kept in
1666 	 * order to maintain the reserve, and those that may be released back to
1667 	 * the system.  Since one set may be much larger than the other,
1668 	 * populate the smaller of the two sets and swap them if necessary.
1669 	 */
1670 	for (i = min(stofree, stokeep); i > 0; i--) {
1671 		slab = LIST_FIRST(&dom->ud_free_slab);
1672 		LIST_REMOVE(slab, us_link);
1673 		LIST_INSERT_HEAD(&freeslabs, slab, us_link);
1674 	}
1675 	if (stofree > stokeep)
1676 		LIST_SWAP(&freeslabs, &dom->ud_free_slab, uma_slab, us_link);
1677 
1678 	if ((keg->uk_flags & UMA_ZFLAG_HASH) != 0) {
1679 		LIST_FOREACH(slab, &freeslabs, us_link)
1680 			UMA_HASH_REMOVE(&keg->uk_hash, slab);
1681 	}
1682 	dom->ud_free_items -= stofree * keg->uk_ipers;
1683 	dom->ud_free_slabs -= stofree;
1684 	dom->ud_pages -= stofree * keg->uk_ppera;
1685 	KEG_UNLOCK(keg, domain);
1686 
1687 	LIST_FOREACH_SAFE(slab, &freeslabs, us_link, tmp)
1688 		keg_free_slab(keg, slab, keg->uk_ipers);
1689 }
1690 
1691 /*
1692  * Frees pages from a keg back to the system.  This is done on demand from
1693  * the pageout daemon.
1694  *
1695  * Returns nothing.
1696  */
1697 static void
1698 keg_drain(uma_keg_t keg, int domain)
1699 {
1700 	int i;
1701 
1702 	if ((keg->uk_flags & UMA_ZONE_NOFREE) != 0)
1703 		return;
1704 	if (domain != UMA_ANYDOMAIN) {
1705 		keg_drain_domain(keg, domain);
1706 	} else {
1707 		for (i = 0; i < vm_ndomains; i++)
1708 			keg_drain_domain(keg, i);
1709 	}
1710 }
1711 
1712 static void
1713 zone_reclaim(uma_zone_t zone, int domain, int waitok, bool drain)
1714 {
1715 	/*
1716 	 * Count active reclaim operations in order to interlock with
1717 	 * zone_dtor(), which removes the zone from global lists before
1718 	 * attempting to reclaim items itself.
1719 	 *
1720 	 * The zone may be destroyed while sleeping, so only zone_dtor() should
1721 	 * specify M_WAITOK.
1722 	 */
1723 	ZONE_LOCK(zone);
1724 	if (waitok == M_WAITOK) {
1725 		while (zone->uz_reclaimers > 0)
1726 			msleep(zone, ZONE_LOCKPTR(zone), PVM, "zonedrain", 1);
1727 	}
1728 	zone->uz_reclaimers++;
1729 	ZONE_UNLOCK(zone);
1730 	bucket_cache_reclaim(zone, drain, domain);
1731 
1732 	if ((zone->uz_flags & UMA_ZFLAG_CACHE) == 0)
1733 		keg_drain(zone->uz_keg, domain);
1734 	ZONE_LOCK(zone);
1735 	zone->uz_reclaimers--;
1736 	if (zone->uz_reclaimers == 0)
1737 		wakeup(zone);
1738 	ZONE_UNLOCK(zone);
1739 }
1740 
1741 /*
1742  * Allocate a new slab for a keg and inserts it into the partial slab list.
1743  * The keg should be unlocked on entry.  If the allocation succeeds it will
1744  * be locked on return.
1745  *
1746  * Arguments:
1747  *	flags   Wait flags for the item initialization routine
1748  *	aflags  Wait flags for the slab allocation
1749  *
1750  * Returns:
1751  *	The slab that was allocated or NULL if there is no memory and the
1752  *	caller specified M_NOWAIT.
1753  */
1754 static uma_slab_t
1755 keg_alloc_slab(uma_keg_t keg, uma_zone_t zone, int domain, int flags,
1756     int aflags)
1757 {
1758 	uma_domain_t dom;
1759 	uma_slab_t slab;
1760 	unsigned long size;
1761 	uint8_t *mem;
1762 	uint8_t sflags;
1763 	int i;
1764 
1765 	TSENTER();
1766 
1767 	KASSERT(domain >= 0 && domain < vm_ndomains,
1768 	    ("keg_alloc_slab: domain %d out of range", domain));
1769 
1770 	slab = NULL;
1771 	mem = NULL;
1772 	if (keg->uk_flags & UMA_ZFLAG_OFFPAGE) {
1773 		uma_hash_slab_t hslab;
1774 		hslab = zone_alloc_item(slabzone(keg->uk_ipers), NULL,
1775 		    domain, aflags);
1776 		if (hslab == NULL)
1777 			goto fail;
1778 		slab = &hslab->uhs_slab;
1779 	}
1780 
1781 	/*
1782 	 * This reproduces the old vm_zone behavior of zero filling pages the
1783 	 * first time they are added to a zone.
1784 	 *
1785 	 * Malloced items are zeroed in uma_zalloc.
1786 	 */
1787 
1788 	if ((keg->uk_flags & UMA_ZONE_MALLOC) == 0)
1789 		aflags |= M_ZERO;
1790 	else
1791 		aflags &= ~M_ZERO;
1792 
1793 	if (keg->uk_flags & UMA_ZONE_NODUMP)
1794 		aflags |= M_NODUMP;
1795 
1796 	/* zone is passed for legacy reasons. */
1797 	size = keg->uk_ppera * PAGE_SIZE;
1798 	mem = keg->uk_allocf(zone, size, domain, &sflags, aflags);
1799 	if (mem == NULL) {
1800 		if (keg->uk_flags & UMA_ZFLAG_OFFPAGE)
1801 			zone_free_item(slabzone(keg->uk_ipers),
1802 			    slab_tohashslab(slab), NULL, SKIP_NONE);
1803 		goto fail;
1804 	}
1805 	uma_total_inc(size);
1806 
1807 	/* For HASH zones all pages go to the same uma_domain. */
1808 	if ((keg->uk_flags & UMA_ZFLAG_HASH) != 0)
1809 		domain = 0;
1810 
1811 	kmsan_mark(mem, size,
1812 	    (aflags & M_ZERO) != 0 ? KMSAN_STATE_INITED : KMSAN_STATE_UNINIT);
1813 
1814 	/* Point the slab into the allocated memory */
1815 	if (!(keg->uk_flags & UMA_ZFLAG_OFFPAGE))
1816 		slab = (uma_slab_t)(mem + keg->uk_pgoff);
1817 	else
1818 		slab_tohashslab(slab)->uhs_data = mem;
1819 
1820 	if (keg->uk_flags & UMA_ZFLAG_VTOSLAB)
1821 		for (i = 0; i < keg->uk_ppera; i++)
1822 			vsetzoneslab((vm_offset_t)mem + (i * PAGE_SIZE),
1823 			    zone, slab);
1824 
1825 	slab->us_freecount = keg->uk_ipers;
1826 	slab->us_flags = sflags;
1827 	slab->us_domain = domain;
1828 
1829 	BIT_FILL(keg->uk_ipers, &slab->us_free);
1830 #ifdef INVARIANTS
1831 	BIT_ZERO(keg->uk_ipers, slab_dbg_bits(slab, keg));
1832 #endif
1833 
1834 	if (keg->uk_init != NULL) {
1835 		for (i = 0; i < keg->uk_ipers; i++)
1836 			if (keg->uk_init(slab_item(slab, keg, i),
1837 			    keg->uk_size, flags) != 0)
1838 				break;
1839 		if (i != keg->uk_ipers) {
1840 			keg_free_slab(keg, slab, i);
1841 			goto fail;
1842 		}
1843 	}
1844 	kasan_mark_slab_invalid(keg, mem);
1845 	KEG_LOCK(keg, domain);
1846 
1847 	CTR3(KTR_UMA, "keg_alloc_slab: allocated slab %p for %s(%p)",
1848 	    slab, keg->uk_name, keg);
1849 
1850 	if (keg->uk_flags & UMA_ZFLAG_HASH)
1851 		UMA_HASH_INSERT(&keg->uk_hash, slab, mem);
1852 
1853 	/*
1854 	 * If we got a slab here it's safe to mark it partially used
1855 	 * and return.  We assume that the caller is going to remove
1856 	 * at least one item.
1857 	 */
1858 	dom = &keg->uk_domain[domain];
1859 	LIST_INSERT_HEAD(&dom->ud_part_slab, slab, us_link);
1860 	dom->ud_pages += keg->uk_ppera;
1861 	dom->ud_free_items += keg->uk_ipers;
1862 
1863 	TSEXIT();
1864 	return (slab);
1865 
1866 fail:
1867 	return (NULL);
1868 }
1869 
1870 /*
1871  * This function is intended to be used early on in place of page_alloc().  It
1872  * performs contiguous physical memory allocations and uses a bump allocator for
1873  * KVA, so is usable before the kernel map is initialized.
1874  */
1875 static void *
1876 startup_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
1877     int wait)
1878 {
1879 	vm_paddr_t pa;
1880 	vm_page_t m;
1881 	int i, pages;
1882 
1883 	pages = howmany(bytes, PAGE_SIZE);
1884 	KASSERT(pages > 0, ("%s can't reserve 0 pages", __func__));
1885 
1886 	*pflag = UMA_SLAB_BOOT;
1887 	m = vm_page_alloc_noobj_contig_domain(domain, malloc2vm_flags(wait) |
1888 	    VM_ALLOC_WIRED, pages, (vm_paddr_t)0, ~(vm_paddr_t)0, 1, 0,
1889 	    VM_MEMATTR_DEFAULT);
1890 	if (m == NULL)
1891 		return (NULL);
1892 
1893 	pa = VM_PAGE_TO_PHYS(m);
1894 	for (i = 0; i < pages; i++, pa += PAGE_SIZE) {
1895 #if defined(__aarch64__) || defined(__amd64__) || \
1896     defined(__riscv) || defined(__powerpc64__)
1897 		if ((wait & M_NODUMP) == 0)
1898 			dump_add_page(pa);
1899 #endif
1900 	}
1901 
1902 	/* Allocate KVA and indirectly advance bootmem. */
1903 	return ((void *)pmap_map(&bootmem, m->phys_addr,
1904 	    m->phys_addr + (pages * PAGE_SIZE), VM_PROT_READ | VM_PROT_WRITE));
1905 }
1906 
1907 static void
1908 startup_free(void *mem, vm_size_t bytes)
1909 {
1910 	vm_offset_t va;
1911 	vm_page_t m;
1912 
1913 	va = (vm_offset_t)mem;
1914 	m = PHYS_TO_VM_PAGE(pmap_kextract(va));
1915 
1916 	/*
1917 	 * startup_alloc() returns direct-mapped slabs on some platforms.  Avoid
1918 	 * unmapping ranges of the direct map.
1919 	 */
1920 	if (va >= bootstart && va + bytes <= bootmem)
1921 		pmap_remove(kernel_pmap, va, va + bytes);
1922 	for (; bytes != 0; bytes -= PAGE_SIZE, m++) {
1923 #if defined(__aarch64__) || defined(__amd64__) || \
1924     defined(__riscv) || defined(__powerpc64__)
1925 		dump_drop_page(VM_PAGE_TO_PHYS(m));
1926 #endif
1927 		vm_page_unwire_noq(m);
1928 		vm_page_free(m);
1929 	}
1930 }
1931 
1932 /*
1933  * Allocates a number of pages from the system
1934  *
1935  * Arguments:
1936  *	bytes  The number of bytes requested
1937  *	wait  Shall we wait?
1938  *
1939  * Returns:
1940  *	A pointer to the alloced memory or possibly
1941  *	NULL if M_NOWAIT is set.
1942  */
1943 static void *
1944 page_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
1945     int wait)
1946 {
1947 	void *p;	/* Returned page */
1948 
1949 	*pflag = UMA_SLAB_KERNEL;
1950 	p = kmem_malloc_domainset(DOMAINSET_FIXED(domain), bytes, wait);
1951 
1952 	return (p);
1953 }
1954 
1955 static void *
1956 pcpu_page_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
1957     int wait)
1958 {
1959 	struct pglist alloctail;
1960 	vm_offset_t addr, zkva;
1961 	int cpu, flags;
1962 	vm_page_t p, p_next;
1963 #ifdef NUMA
1964 	struct pcpu *pc;
1965 #endif
1966 
1967 	MPASS(bytes == (mp_maxid + 1) * PAGE_SIZE);
1968 
1969 	TAILQ_INIT(&alloctail);
1970 	flags = VM_ALLOC_SYSTEM | VM_ALLOC_WIRED | malloc2vm_flags(wait);
1971 	*pflag = UMA_SLAB_KERNEL;
1972 	for (cpu = 0; cpu <= mp_maxid; cpu++) {
1973 		if (CPU_ABSENT(cpu)) {
1974 			p = vm_page_alloc_noobj(flags);
1975 		} else {
1976 #ifndef NUMA
1977 			p = vm_page_alloc_noobj(flags);
1978 #else
1979 			pc = pcpu_find(cpu);
1980 			if (__predict_false(VM_DOMAIN_EMPTY(pc->pc_domain)))
1981 				p = NULL;
1982 			else
1983 				p = vm_page_alloc_noobj_domain(pc->pc_domain,
1984 				    flags);
1985 			if (__predict_false(p == NULL))
1986 				p = vm_page_alloc_noobj(flags);
1987 #endif
1988 		}
1989 		if (__predict_false(p == NULL))
1990 			goto fail;
1991 		TAILQ_INSERT_TAIL(&alloctail, p, listq);
1992 	}
1993 	if ((addr = kva_alloc(bytes)) == 0)
1994 		goto fail;
1995 	zkva = addr;
1996 	TAILQ_FOREACH(p, &alloctail, listq) {
1997 		pmap_qenter(zkva, &p, 1);
1998 		zkva += PAGE_SIZE;
1999 	}
2000 	return ((void*)addr);
2001 fail:
2002 	TAILQ_FOREACH_SAFE(p, &alloctail, listq, p_next) {
2003 		vm_page_unwire_noq(p);
2004 		vm_page_free(p);
2005 	}
2006 	return (NULL);
2007 }
2008 
2009 /*
2010  * Allocates a number of pages not belonging to a VM object
2011  *
2012  * Arguments:
2013  *	bytes  The number of bytes requested
2014  *	wait   Shall we wait?
2015  *
2016  * Returns:
2017  *	A pointer to the alloced memory or possibly
2018  *	NULL if M_NOWAIT is set.
2019  */
2020 static void *
2021 noobj_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *flags,
2022     int wait)
2023 {
2024 	TAILQ_HEAD(, vm_page) alloctail;
2025 	u_long npages;
2026 	vm_offset_t retkva, zkva;
2027 	vm_page_t p, p_next;
2028 	uma_keg_t keg;
2029 	int req;
2030 
2031 	TAILQ_INIT(&alloctail);
2032 	keg = zone->uz_keg;
2033 	req = VM_ALLOC_INTERRUPT | VM_ALLOC_WIRED;
2034 	if ((wait & M_WAITOK) != 0)
2035 		req |= VM_ALLOC_WAITOK;
2036 
2037 	npages = howmany(bytes, PAGE_SIZE);
2038 	while (npages > 0) {
2039 		p = vm_page_alloc_noobj_domain(domain, req);
2040 		if (p != NULL) {
2041 			/*
2042 			 * Since the page does not belong to an object, its
2043 			 * listq is unused.
2044 			 */
2045 			TAILQ_INSERT_TAIL(&alloctail, p, listq);
2046 			npages--;
2047 			continue;
2048 		}
2049 		/*
2050 		 * Page allocation failed, free intermediate pages and
2051 		 * exit.
2052 		 */
2053 		TAILQ_FOREACH_SAFE(p, &alloctail, listq, p_next) {
2054 			vm_page_unwire_noq(p);
2055 			vm_page_free(p);
2056 		}
2057 		return (NULL);
2058 	}
2059 	*flags = UMA_SLAB_PRIV;
2060 	zkva = keg->uk_kva +
2061 	    atomic_fetchadd_long(&keg->uk_offset, round_page(bytes));
2062 	retkva = zkva;
2063 	TAILQ_FOREACH(p, &alloctail, listq) {
2064 		pmap_qenter(zkva, &p, 1);
2065 		zkva += PAGE_SIZE;
2066 	}
2067 
2068 	return ((void *)retkva);
2069 }
2070 
2071 /*
2072  * Allocate physically contiguous pages.
2073  */
2074 static void *
2075 contig_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
2076     int wait)
2077 {
2078 
2079 	*pflag = UMA_SLAB_KERNEL;
2080 	return ((void *)kmem_alloc_contig_domainset(DOMAINSET_FIXED(domain),
2081 	    bytes, wait, 0, ~(vm_paddr_t)0, 1, 0, VM_MEMATTR_DEFAULT));
2082 }
2083 
2084 /*
2085  * Frees a number of pages to the system
2086  *
2087  * Arguments:
2088  *	mem   A pointer to the memory to be freed
2089  *	size  The size of the memory being freed
2090  *	flags The original p->us_flags field
2091  *
2092  * Returns:
2093  *	Nothing
2094  */
2095 static void
2096 page_free(void *mem, vm_size_t size, uint8_t flags)
2097 {
2098 
2099 	if ((flags & UMA_SLAB_BOOT) != 0) {
2100 		startup_free(mem, size);
2101 		return;
2102 	}
2103 
2104 	KASSERT((flags & UMA_SLAB_KERNEL) != 0,
2105 	    ("UMA: page_free used with invalid flags %x", flags));
2106 
2107 	kmem_free(mem, size);
2108 }
2109 
2110 /*
2111  * Frees pcpu zone allocations
2112  *
2113  * Arguments:
2114  *	mem   A pointer to the memory to be freed
2115  *	size  The size of the memory being freed
2116  *	flags The original p->us_flags field
2117  *
2118  * Returns:
2119  *	Nothing
2120  */
2121 static void
2122 pcpu_page_free(void *mem, vm_size_t size, uint8_t flags)
2123 {
2124 	vm_offset_t sva, curva;
2125 	vm_paddr_t paddr;
2126 	vm_page_t m;
2127 
2128 	MPASS(size == (mp_maxid+1)*PAGE_SIZE);
2129 
2130 	if ((flags & UMA_SLAB_BOOT) != 0) {
2131 		startup_free(mem, size);
2132 		return;
2133 	}
2134 
2135 	sva = (vm_offset_t)mem;
2136 	for (curva = sva; curva < sva + size; curva += PAGE_SIZE) {
2137 		paddr = pmap_kextract(curva);
2138 		m = PHYS_TO_VM_PAGE(paddr);
2139 		vm_page_unwire_noq(m);
2140 		vm_page_free(m);
2141 	}
2142 	pmap_qremove(sva, size >> PAGE_SHIFT);
2143 	kva_free(sva, size);
2144 }
2145 
2146 /*
2147  * Zero fill initializer
2148  *
2149  * Arguments/Returns follow uma_init specifications
2150  */
2151 static int
2152 zero_init(void *mem, int size, int flags)
2153 {
2154 	bzero(mem, size);
2155 	return (0);
2156 }
2157 
2158 #ifdef INVARIANTS
2159 static struct noslabbits *
2160 slab_dbg_bits(uma_slab_t slab, uma_keg_t keg)
2161 {
2162 
2163 	return ((void *)((char *)&slab->us_free + BITSET_SIZE(keg->uk_ipers)));
2164 }
2165 #endif
2166 
2167 /*
2168  * Actual size of embedded struct slab (!OFFPAGE).
2169  */
2170 static size_t
2171 slab_sizeof(int nitems)
2172 {
2173 	size_t s;
2174 
2175 	s = sizeof(struct uma_slab) + BITSET_SIZE(nitems) * SLAB_BITSETS;
2176 	return (roundup(s, UMA_ALIGN_PTR + 1));
2177 }
2178 
2179 #define	UMA_FIXPT_SHIFT	31
2180 #define	UMA_FRAC_FIXPT(n, d)						\
2181 	((uint32_t)(((uint64_t)(n) << UMA_FIXPT_SHIFT) / (d)))
2182 #define	UMA_FIXPT_PCT(f)						\
2183 	((u_int)(((uint64_t)100 * (f)) >> UMA_FIXPT_SHIFT))
2184 #define	UMA_PCT_FIXPT(pct)	UMA_FRAC_FIXPT((pct), 100)
2185 #define	UMA_MIN_EFF	UMA_PCT_FIXPT(100 - UMA_MAX_WASTE)
2186 
2187 /*
2188  * Compute the number of items that will fit in a slab.  If hdr is true, the
2189  * item count may be limited to provide space in the slab for an inline slab
2190  * header.  Otherwise, all slab space will be provided for item storage.
2191  */
2192 static u_int
2193 slab_ipers_hdr(u_int size, u_int rsize, u_int slabsize, bool hdr)
2194 {
2195 	u_int ipers;
2196 	u_int padpi;
2197 
2198 	/* The padding between items is not needed after the last item. */
2199 	padpi = rsize - size;
2200 
2201 	if (hdr) {
2202 		/*
2203 		 * Start with the maximum item count and remove items until
2204 		 * the slab header first alongside the allocatable memory.
2205 		 */
2206 		for (ipers = MIN(SLAB_MAX_SETSIZE,
2207 		    (slabsize + padpi - slab_sizeof(1)) / rsize);
2208 		    ipers > 0 &&
2209 		    ipers * rsize - padpi + slab_sizeof(ipers) > slabsize;
2210 		    ipers--)
2211 			continue;
2212 	} else {
2213 		ipers = MIN((slabsize + padpi) / rsize, SLAB_MAX_SETSIZE);
2214 	}
2215 
2216 	return (ipers);
2217 }
2218 
2219 struct keg_layout_result {
2220 	u_int format;
2221 	u_int slabsize;
2222 	u_int ipers;
2223 	u_int eff;
2224 };
2225 
2226 static void
2227 keg_layout_one(uma_keg_t keg, u_int rsize, u_int slabsize, u_int fmt,
2228     struct keg_layout_result *kl)
2229 {
2230 	u_int total;
2231 
2232 	kl->format = fmt;
2233 	kl->slabsize = slabsize;
2234 
2235 	/* Handle INTERNAL as inline with an extra page. */
2236 	if ((fmt & UMA_ZFLAG_INTERNAL) != 0) {
2237 		kl->format &= ~UMA_ZFLAG_INTERNAL;
2238 		kl->slabsize += PAGE_SIZE;
2239 	}
2240 
2241 	kl->ipers = slab_ipers_hdr(keg->uk_size, rsize, kl->slabsize,
2242 	    (fmt & UMA_ZFLAG_OFFPAGE) == 0);
2243 
2244 	/* Account for memory used by an offpage slab header. */
2245 	total = kl->slabsize;
2246 	if ((fmt & UMA_ZFLAG_OFFPAGE) != 0)
2247 		total += slabzone(kl->ipers)->uz_keg->uk_rsize;
2248 
2249 	kl->eff = UMA_FRAC_FIXPT(kl->ipers * rsize, total);
2250 }
2251 
2252 /*
2253  * Determine the format of a uma keg.  This determines where the slab header
2254  * will be placed (inline or offpage) and calculates ipers, rsize, and ppera.
2255  *
2256  * Arguments
2257  *	keg  The zone we should initialize
2258  *
2259  * Returns
2260  *	Nothing
2261  */
2262 static void
2263 keg_layout(uma_keg_t keg)
2264 {
2265 	struct keg_layout_result kl = {}, kl_tmp;
2266 	u_int fmts[2];
2267 	u_int alignsize;
2268 	u_int nfmt;
2269 	u_int pages;
2270 	u_int rsize;
2271 	u_int slabsize;
2272 	u_int i, j;
2273 
2274 	KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0 ||
2275 	    (keg->uk_size <= UMA_PCPU_ALLOC_SIZE &&
2276 	     (keg->uk_flags & UMA_ZONE_CACHESPREAD) == 0),
2277 	    ("%s: cannot configure for PCPU: keg=%s, size=%u, flags=0x%b",
2278 	     __func__, keg->uk_name, keg->uk_size, keg->uk_flags,
2279 	     PRINT_UMA_ZFLAGS));
2280 	KASSERT((keg->uk_flags & (UMA_ZFLAG_INTERNAL | UMA_ZONE_VM)) == 0 ||
2281 	    (keg->uk_flags & (UMA_ZONE_NOTOUCH | UMA_ZONE_PCPU)) == 0,
2282 	    ("%s: incompatible flags 0x%b", __func__, keg->uk_flags,
2283 	     PRINT_UMA_ZFLAGS));
2284 
2285 	alignsize = keg->uk_align + 1;
2286 #ifdef KASAN
2287 	/*
2288 	 * ASAN requires that each allocation be aligned to the shadow map
2289 	 * scale factor.
2290 	 */
2291 	if (alignsize < KASAN_SHADOW_SCALE)
2292 		alignsize = KASAN_SHADOW_SCALE;
2293 #endif
2294 
2295 	/*
2296 	 * Calculate the size of each allocation (rsize) according to
2297 	 * alignment.  If the requested size is smaller than we have
2298 	 * allocation bits for we round it up.
2299 	 */
2300 	rsize = MAX(keg->uk_size, UMA_SMALLEST_UNIT);
2301 	rsize = roundup2(rsize, alignsize);
2302 
2303 	if ((keg->uk_flags & UMA_ZONE_CACHESPREAD) != 0) {
2304 		/*
2305 		 * We want one item to start on every align boundary in a page.
2306 		 * To do this we will span pages.  We will also extend the item
2307 		 * by the size of align if it is an even multiple of align.
2308 		 * Otherwise, it would fall on the same boundary every time.
2309 		 */
2310 		if ((rsize & alignsize) == 0)
2311 			rsize += alignsize;
2312 		slabsize = rsize * (PAGE_SIZE / alignsize);
2313 		slabsize = MIN(slabsize, rsize * SLAB_MAX_SETSIZE);
2314 		slabsize = MIN(slabsize, UMA_CACHESPREAD_MAX_SIZE);
2315 		slabsize = round_page(slabsize);
2316 	} else {
2317 		/*
2318 		 * Start with a slab size of as many pages as it takes to
2319 		 * represent a single item.  We will try to fit as many
2320 		 * additional items into the slab as possible.
2321 		 */
2322 		slabsize = round_page(keg->uk_size);
2323 	}
2324 
2325 	/* Build a list of all of the available formats for this keg. */
2326 	nfmt = 0;
2327 
2328 	/* Evaluate an inline slab layout. */
2329 	if ((keg->uk_flags & (UMA_ZONE_NOTOUCH | UMA_ZONE_PCPU)) == 0)
2330 		fmts[nfmt++] = 0;
2331 
2332 	/* TODO: vm_page-embedded slab. */
2333 
2334 	/*
2335 	 * We can't do OFFPAGE if we're internal or if we've been
2336 	 * asked to not go to the VM for buckets.  If we do this we
2337 	 * may end up going to the VM for slabs which we do not want
2338 	 * to do if we're UMA_ZONE_VM, which clearly forbids it.
2339 	 * In those cases, evaluate a pseudo-format called INTERNAL
2340 	 * which has an inline slab header and one extra page to
2341 	 * guarantee that it fits.
2342 	 *
2343 	 * Otherwise, see if using an OFFPAGE slab will improve our
2344 	 * efficiency.
2345 	 */
2346 	if ((keg->uk_flags & (UMA_ZFLAG_INTERNAL | UMA_ZONE_VM)) != 0)
2347 		fmts[nfmt++] = UMA_ZFLAG_INTERNAL;
2348 	else
2349 		fmts[nfmt++] = UMA_ZFLAG_OFFPAGE;
2350 
2351 	/*
2352 	 * Choose a slab size and format which satisfy the minimum efficiency.
2353 	 * Prefer the smallest slab size that meets the constraints.
2354 	 *
2355 	 * Start with a minimum slab size, to accommodate CACHESPREAD.  Then,
2356 	 * for small items (up to PAGE_SIZE), the iteration increment is one
2357 	 * page; and for large items, the increment is one item.
2358 	 */
2359 	i = (slabsize + rsize - keg->uk_size) / MAX(PAGE_SIZE, rsize);
2360 	KASSERT(i >= 1, ("keg %s(%p) flags=0x%b slabsize=%u, rsize=%u, i=%u",
2361 	    keg->uk_name, keg, keg->uk_flags, PRINT_UMA_ZFLAGS, slabsize,
2362 	    rsize, i));
2363 	for ( ; ; i++) {
2364 		slabsize = (rsize <= PAGE_SIZE) ? ptoa(i) :
2365 		    round_page(rsize * (i - 1) + keg->uk_size);
2366 
2367 		for (j = 0; j < nfmt; j++) {
2368 			/* Only if we have no viable format yet. */
2369 			if ((fmts[j] & UMA_ZFLAG_INTERNAL) != 0 &&
2370 			    kl.ipers > 0)
2371 				continue;
2372 
2373 			keg_layout_one(keg, rsize, slabsize, fmts[j], &kl_tmp);
2374 			if (kl_tmp.eff <= kl.eff)
2375 				continue;
2376 
2377 			kl = kl_tmp;
2378 
2379 			CTR6(KTR_UMA, "keg %s layout: format %#x "
2380 			    "(ipers %u * rsize %u) / slabsize %#x = %u%% eff",
2381 			    keg->uk_name, kl.format, kl.ipers, rsize,
2382 			    kl.slabsize, UMA_FIXPT_PCT(kl.eff));
2383 
2384 			/* Stop when we reach the minimum efficiency. */
2385 			if (kl.eff >= UMA_MIN_EFF)
2386 				break;
2387 		}
2388 
2389 		if (kl.eff >= UMA_MIN_EFF || !multipage_slabs ||
2390 		    slabsize >= SLAB_MAX_SETSIZE * rsize ||
2391 		    (keg->uk_flags & (UMA_ZONE_PCPU | UMA_ZONE_CONTIG)) != 0)
2392 			break;
2393 	}
2394 
2395 	pages = atop(kl.slabsize);
2396 	if ((keg->uk_flags & UMA_ZONE_PCPU) != 0)
2397 		pages *= mp_maxid + 1;
2398 
2399 	keg->uk_rsize = rsize;
2400 	keg->uk_ipers = kl.ipers;
2401 	keg->uk_ppera = pages;
2402 	keg->uk_flags |= kl.format;
2403 
2404 	/*
2405 	 * How do we find the slab header if it is offpage or if not all item
2406 	 * start addresses are in the same page?  We could solve the latter
2407 	 * case with vaddr alignment, but we don't.
2408 	 */
2409 	if ((keg->uk_flags & UMA_ZFLAG_OFFPAGE) != 0 ||
2410 	    (keg->uk_ipers - 1) * rsize >= PAGE_SIZE) {
2411 		if ((keg->uk_flags & UMA_ZONE_NOTPAGE) != 0)
2412 			keg->uk_flags |= UMA_ZFLAG_HASH;
2413 		else
2414 			keg->uk_flags |= UMA_ZFLAG_VTOSLAB;
2415 	}
2416 
2417 	CTR6(KTR_UMA, "%s: keg=%s, flags=%#x, rsize=%u, ipers=%u, ppera=%u",
2418 	    __func__, keg->uk_name, keg->uk_flags, rsize, keg->uk_ipers,
2419 	    pages);
2420 	KASSERT(keg->uk_ipers > 0 && keg->uk_ipers <= SLAB_MAX_SETSIZE,
2421 	    ("%s: keg=%s, flags=0x%b, rsize=%u, ipers=%u, ppera=%u", __func__,
2422 	     keg->uk_name, keg->uk_flags, PRINT_UMA_ZFLAGS, rsize,
2423 	     keg->uk_ipers, pages));
2424 }
2425 
2426 /*
2427  * Keg header ctor.  This initializes all fields, locks, etc.  And inserts
2428  * the keg onto the global keg list.
2429  *
2430  * Arguments/Returns follow uma_ctor specifications
2431  *	udata  Actually uma_kctor_args
2432  */
2433 static int
2434 keg_ctor(void *mem, int size, void *udata, int flags)
2435 {
2436 	struct uma_kctor_args *arg = udata;
2437 	uma_keg_t keg = mem;
2438 	uma_zone_t zone;
2439 	int i;
2440 
2441 	bzero(keg, size);
2442 	keg->uk_size = arg->size;
2443 	keg->uk_init = arg->uminit;
2444 	keg->uk_fini = arg->fini;
2445 	keg->uk_align = arg->align;
2446 	keg->uk_reserve = 0;
2447 	keg->uk_flags = arg->flags;
2448 
2449 	/*
2450 	 * We use a global round-robin policy by default.  Zones with
2451 	 * UMA_ZONE_FIRSTTOUCH set will use first-touch instead, in which
2452 	 * case the iterator is never run.
2453 	 */
2454 	keg->uk_dr.dr_policy = DOMAINSET_RR();
2455 	keg->uk_dr.dr_iter = 0;
2456 
2457 	/*
2458 	 * The primary zone is passed to us at keg-creation time.
2459 	 */
2460 	zone = arg->zone;
2461 	keg->uk_name = zone->uz_name;
2462 
2463 	if (arg->flags & UMA_ZONE_ZINIT)
2464 		keg->uk_init = zero_init;
2465 
2466 	if (arg->flags & UMA_ZONE_MALLOC)
2467 		keg->uk_flags |= UMA_ZFLAG_VTOSLAB;
2468 
2469 #ifndef SMP
2470 	keg->uk_flags &= ~UMA_ZONE_PCPU;
2471 #endif
2472 
2473 	keg_layout(keg);
2474 
2475 	/*
2476 	 * Use a first-touch NUMA policy for kegs that pmap_extract() will
2477 	 * work on.  Use round-robin for everything else.
2478 	 *
2479 	 * Zones may override the default by specifying either.
2480 	 */
2481 #ifdef NUMA
2482 	if ((keg->uk_flags &
2483 	    (UMA_ZONE_ROUNDROBIN | UMA_ZFLAG_CACHE | UMA_ZONE_NOTPAGE)) == 0)
2484 		keg->uk_flags |= UMA_ZONE_FIRSTTOUCH;
2485 	else if ((keg->uk_flags & UMA_ZONE_FIRSTTOUCH) == 0)
2486 		keg->uk_flags |= UMA_ZONE_ROUNDROBIN;
2487 #endif
2488 
2489 	/*
2490 	 * If we haven't booted yet we need allocations to go through the
2491 	 * startup cache until the vm is ready.
2492 	 */
2493 #ifdef UMA_MD_SMALL_ALLOC
2494 	if (keg->uk_ppera == 1)
2495 		keg->uk_allocf = uma_small_alloc;
2496 	else
2497 #endif
2498 	if (booted < BOOT_KVA)
2499 		keg->uk_allocf = startup_alloc;
2500 	else if (keg->uk_flags & UMA_ZONE_PCPU)
2501 		keg->uk_allocf = pcpu_page_alloc;
2502 	else if ((keg->uk_flags & UMA_ZONE_CONTIG) != 0 && keg->uk_ppera > 1)
2503 		keg->uk_allocf = contig_alloc;
2504 	else
2505 		keg->uk_allocf = page_alloc;
2506 #ifdef UMA_MD_SMALL_ALLOC
2507 	if (keg->uk_ppera == 1)
2508 		keg->uk_freef = uma_small_free;
2509 	else
2510 #endif
2511 	if (keg->uk_flags & UMA_ZONE_PCPU)
2512 		keg->uk_freef = pcpu_page_free;
2513 	else
2514 		keg->uk_freef = page_free;
2515 
2516 	/*
2517 	 * Initialize keg's locks.
2518 	 */
2519 	for (i = 0; i < vm_ndomains; i++)
2520 		KEG_LOCK_INIT(keg, i, (arg->flags & UMA_ZONE_MTXCLASS));
2521 
2522 	/*
2523 	 * If we're putting the slab header in the actual page we need to
2524 	 * figure out where in each page it goes.  See slab_sizeof
2525 	 * definition.
2526 	 */
2527 	if (!(keg->uk_flags & UMA_ZFLAG_OFFPAGE)) {
2528 		size_t shsize;
2529 
2530 		shsize = slab_sizeof(keg->uk_ipers);
2531 		keg->uk_pgoff = (PAGE_SIZE * keg->uk_ppera) - shsize;
2532 		/*
2533 		 * The only way the following is possible is if with our
2534 		 * UMA_ALIGN_PTR adjustments we are now bigger than
2535 		 * UMA_SLAB_SIZE.  I haven't checked whether this is
2536 		 * mathematically possible for all cases, so we make
2537 		 * sure here anyway.
2538 		 */
2539 		KASSERT(keg->uk_pgoff + shsize <= PAGE_SIZE * keg->uk_ppera,
2540 		    ("zone %s ipers %d rsize %d size %d slab won't fit",
2541 		    zone->uz_name, keg->uk_ipers, keg->uk_rsize, keg->uk_size));
2542 	}
2543 
2544 	if (keg->uk_flags & UMA_ZFLAG_HASH)
2545 		hash_alloc(&keg->uk_hash, 0);
2546 
2547 	CTR3(KTR_UMA, "keg_ctor %p zone %s(%p)", keg, zone->uz_name, zone);
2548 
2549 	LIST_INSERT_HEAD(&keg->uk_zones, zone, uz_link);
2550 
2551 	rw_wlock(&uma_rwlock);
2552 	LIST_INSERT_HEAD(&uma_kegs, keg, uk_link);
2553 	rw_wunlock(&uma_rwlock);
2554 	return (0);
2555 }
2556 
2557 static void
2558 zone_kva_available(uma_zone_t zone, void *unused)
2559 {
2560 	uma_keg_t keg;
2561 
2562 	if ((zone->uz_flags & UMA_ZFLAG_CACHE) != 0)
2563 		return;
2564 	KEG_GET(zone, keg);
2565 
2566 	if (keg->uk_allocf == startup_alloc) {
2567 		/* Switch to the real allocator. */
2568 		if (keg->uk_flags & UMA_ZONE_PCPU)
2569 			keg->uk_allocf = pcpu_page_alloc;
2570 		else if ((keg->uk_flags & UMA_ZONE_CONTIG) != 0 &&
2571 		    keg->uk_ppera > 1)
2572 			keg->uk_allocf = contig_alloc;
2573 		else
2574 			keg->uk_allocf = page_alloc;
2575 	}
2576 }
2577 
2578 static void
2579 zone_alloc_counters(uma_zone_t zone, void *unused)
2580 {
2581 
2582 	zone->uz_allocs = counter_u64_alloc(M_WAITOK);
2583 	zone->uz_frees = counter_u64_alloc(M_WAITOK);
2584 	zone->uz_fails = counter_u64_alloc(M_WAITOK);
2585 	zone->uz_xdomain = counter_u64_alloc(M_WAITOK);
2586 }
2587 
2588 static void
2589 zone_alloc_sysctl(uma_zone_t zone, void *unused)
2590 {
2591 	uma_zone_domain_t zdom;
2592 	uma_domain_t dom;
2593 	uma_keg_t keg;
2594 	struct sysctl_oid *oid, *domainoid;
2595 	int domains, i, cnt;
2596 	static const char *nokeg = "cache zone";
2597 	char *c;
2598 
2599 	/*
2600 	 * Make a sysctl safe copy of the zone name by removing
2601 	 * any special characters and handling dups by appending
2602 	 * an index.
2603 	 */
2604 	if (zone->uz_namecnt != 0) {
2605 		/* Count the number of decimal digits and '_' separator. */
2606 		for (i = 1, cnt = zone->uz_namecnt; cnt != 0; i++)
2607 			cnt /= 10;
2608 		zone->uz_ctlname = malloc(strlen(zone->uz_name) + i + 1,
2609 		    M_UMA, M_WAITOK);
2610 		sprintf(zone->uz_ctlname, "%s_%d", zone->uz_name,
2611 		    zone->uz_namecnt);
2612 	} else
2613 		zone->uz_ctlname = strdup(zone->uz_name, M_UMA);
2614 	for (c = zone->uz_ctlname; *c != '\0'; c++)
2615 		if (strchr("./\\ -", *c) != NULL)
2616 			*c = '_';
2617 
2618 	/*
2619 	 * Basic parameters at the root.
2620 	 */
2621 	zone->uz_oid = SYSCTL_ADD_NODE(NULL, SYSCTL_STATIC_CHILDREN(_vm_uma),
2622 	    OID_AUTO, zone->uz_ctlname, CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2623 	oid = zone->uz_oid;
2624 	SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2625 	    "size", CTLFLAG_RD, &zone->uz_size, 0, "Allocation size");
2626 	SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2627 	    "flags", CTLFLAG_RD | CTLTYPE_STRING | CTLFLAG_MPSAFE,
2628 	    zone, 0, sysctl_handle_uma_zone_flags, "A",
2629 	    "Allocator configuration flags");
2630 	SYSCTL_ADD_U16(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2631 	    "bucket_size", CTLFLAG_RD, &zone->uz_bucket_size, 0,
2632 	    "Desired per-cpu cache size");
2633 	SYSCTL_ADD_U16(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2634 	    "bucket_size_max", CTLFLAG_RD, &zone->uz_bucket_size_max, 0,
2635 	    "Maximum allowed per-cpu cache size");
2636 
2637 	/*
2638 	 * keg if present.
2639 	 */
2640 	if ((zone->uz_flags & UMA_ZFLAG_HASH) == 0)
2641 		domains = vm_ndomains;
2642 	else
2643 		domains = 1;
2644 	oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(zone->uz_oid), OID_AUTO,
2645 	    "keg", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2646 	keg = zone->uz_keg;
2647 	if ((zone->uz_flags & UMA_ZFLAG_CACHE) == 0) {
2648 		SYSCTL_ADD_CONST_STRING(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2649 		    "name", CTLFLAG_RD, keg->uk_name, "Keg name");
2650 		SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2651 		    "rsize", CTLFLAG_RD, &keg->uk_rsize, 0,
2652 		    "Real object size with alignment");
2653 		SYSCTL_ADD_U16(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2654 		    "ppera", CTLFLAG_RD, &keg->uk_ppera, 0,
2655 		    "pages per-slab allocation");
2656 		SYSCTL_ADD_U16(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2657 		    "ipers", CTLFLAG_RD, &keg->uk_ipers, 0,
2658 		    "items available per-slab");
2659 		SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2660 		    "align", CTLFLAG_RD, &keg->uk_align, 0,
2661 		    "item alignment mask");
2662 		SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2663 		    "reserve", CTLFLAG_RD, &keg->uk_reserve, 0,
2664 		    "number of reserved items");
2665 		SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2666 		    "efficiency", CTLFLAG_RD | CTLTYPE_INT | CTLFLAG_MPSAFE,
2667 		    keg, 0, sysctl_handle_uma_slab_efficiency, "I",
2668 		    "Slab utilization (100 - internal fragmentation %)");
2669 		domainoid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(oid),
2670 		    OID_AUTO, "domain", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2671 		for (i = 0; i < domains; i++) {
2672 			dom = &keg->uk_domain[i];
2673 			oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(domainoid),
2674 			    OID_AUTO, VM_DOMAIN(i)->vmd_name,
2675 			    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2676 			SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2677 			    "pages", CTLFLAG_RD, &dom->ud_pages, 0,
2678 			    "Total pages currently allocated from VM");
2679 			SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2680 			    "free_items", CTLFLAG_RD, &dom->ud_free_items, 0,
2681 			    "Items free in the slab layer");
2682 			SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2683 			    "free_slabs", CTLFLAG_RD, &dom->ud_free_slabs, 0,
2684 			    "Unused slabs");
2685 		}
2686 	} else
2687 		SYSCTL_ADD_CONST_STRING(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2688 		    "name", CTLFLAG_RD, nokeg, "Keg name");
2689 
2690 	/*
2691 	 * Information about zone limits.
2692 	 */
2693 	oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(zone->uz_oid), OID_AUTO,
2694 	    "limit", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2695 	SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2696 	    "items", CTLFLAG_RD | CTLTYPE_U64 | CTLFLAG_MPSAFE,
2697 	    zone, 0, sysctl_handle_uma_zone_items, "QU",
2698 	    "Current number of allocated items if limit is set");
2699 	SYSCTL_ADD_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2700 	    "max_items", CTLFLAG_RD, &zone->uz_max_items, 0,
2701 	    "Maximum number of allocated and cached items");
2702 	SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2703 	    "sleepers", CTLFLAG_RD, &zone->uz_sleepers, 0,
2704 	    "Number of threads sleeping at limit");
2705 	SYSCTL_ADD_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2706 	    "sleeps", CTLFLAG_RD, &zone->uz_sleeps, 0,
2707 	    "Total zone limit sleeps");
2708 	SYSCTL_ADD_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2709 	    "bucket_max", CTLFLAG_RD, &zone->uz_bucket_max, 0,
2710 	    "Maximum number of items in each domain's bucket cache");
2711 
2712 	/*
2713 	 * Per-domain zone information.
2714 	 */
2715 	domainoid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(zone->uz_oid),
2716 	    OID_AUTO, "domain", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2717 	for (i = 0; i < domains; i++) {
2718 		zdom = ZDOM_GET(zone, i);
2719 		oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(domainoid),
2720 		    OID_AUTO, VM_DOMAIN(i)->vmd_name,
2721 		    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2722 		SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2723 		    "nitems", CTLFLAG_RD, &zdom->uzd_nitems,
2724 		    "number of items in this domain");
2725 		SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2726 		    "imax", CTLFLAG_RD, &zdom->uzd_imax,
2727 		    "maximum item count in this period");
2728 		SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2729 		    "imin", CTLFLAG_RD, &zdom->uzd_imin,
2730 		    "minimum item count in this period");
2731 		SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2732 		    "bimin", CTLFLAG_RD, &zdom->uzd_bimin,
2733 		    "Minimum item count in this batch");
2734 		SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2735 		    "wss", CTLFLAG_RD, &zdom->uzd_wss,
2736 		    "Working set size");
2737 		SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2738 		    "limin", CTLFLAG_RD, &zdom->uzd_limin,
2739 		    "Long time minimum item count");
2740 		SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2741 		    "timin", CTLFLAG_RD, &zdom->uzd_timin, 0,
2742 		    "Time since zero long time minimum item count");
2743 	}
2744 
2745 	/*
2746 	 * General statistics.
2747 	 */
2748 	oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(zone->uz_oid), OID_AUTO,
2749 	    "stats", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2750 	SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2751 	    "current", CTLFLAG_RD | CTLTYPE_INT | CTLFLAG_MPSAFE,
2752 	    zone, 1, sysctl_handle_uma_zone_cur, "I",
2753 	    "Current number of allocated items");
2754 	SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2755 	    "allocs", CTLFLAG_RD | CTLTYPE_U64 | CTLFLAG_MPSAFE,
2756 	    zone, 0, sysctl_handle_uma_zone_allocs, "QU",
2757 	    "Total allocation calls");
2758 	SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2759 	    "frees", CTLFLAG_RD | CTLTYPE_U64 | CTLFLAG_MPSAFE,
2760 	    zone, 0, sysctl_handle_uma_zone_frees, "QU",
2761 	    "Total free calls");
2762 	SYSCTL_ADD_COUNTER_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2763 	    "fails", CTLFLAG_RD, &zone->uz_fails,
2764 	    "Number of allocation failures");
2765 	SYSCTL_ADD_COUNTER_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2766 	    "xdomain", CTLFLAG_RD, &zone->uz_xdomain,
2767 	    "Free calls from the wrong domain");
2768 }
2769 
2770 struct uma_zone_count {
2771 	const char	*name;
2772 	int		count;
2773 };
2774 
2775 static void
2776 zone_count(uma_zone_t zone, void *arg)
2777 {
2778 	struct uma_zone_count *cnt;
2779 
2780 	cnt = arg;
2781 	/*
2782 	 * Some zones are rapidly created with identical names and
2783 	 * destroyed out of order.  This can lead to gaps in the count.
2784 	 * Use one greater than the maximum observed for this name.
2785 	 */
2786 	if (strcmp(zone->uz_name, cnt->name) == 0)
2787 		cnt->count = MAX(cnt->count,
2788 		    zone->uz_namecnt + 1);
2789 }
2790 
2791 static void
2792 zone_update_caches(uma_zone_t zone)
2793 {
2794 	int i;
2795 
2796 	for (i = 0; i <= mp_maxid; i++) {
2797 		cache_set_uz_size(&zone->uz_cpu[i], zone->uz_size);
2798 		cache_set_uz_flags(&zone->uz_cpu[i], zone->uz_flags);
2799 	}
2800 }
2801 
2802 /*
2803  * Zone header ctor.  This initializes all fields, locks, etc.
2804  *
2805  * Arguments/Returns follow uma_ctor specifications
2806  *	udata  Actually uma_zctor_args
2807  */
2808 static int
2809 zone_ctor(void *mem, int size, void *udata, int flags)
2810 {
2811 	struct uma_zone_count cnt;
2812 	struct uma_zctor_args *arg = udata;
2813 	uma_zone_domain_t zdom;
2814 	uma_zone_t zone = mem;
2815 	uma_zone_t z;
2816 	uma_keg_t keg;
2817 	int i;
2818 
2819 	bzero(zone, size);
2820 	zone->uz_name = arg->name;
2821 	zone->uz_ctor = arg->ctor;
2822 	zone->uz_dtor = arg->dtor;
2823 	zone->uz_init = NULL;
2824 	zone->uz_fini = NULL;
2825 	zone->uz_sleeps = 0;
2826 	zone->uz_bucket_size = 0;
2827 	zone->uz_bucket_size_min = 0;
2828 	zone->uz_bucket_size_max = BUCKET_MAX;
2829 	zone->uz_flags = (arg->flags & UMA_ZONE_SMR);
2830 	zone->uz_warning = NULL;
2831 	/* The domain structures follow the cpu structures. */
2832 	zone->uz_bucket_max = ULONG_MAX;
2833 	timevalclear(&zone->uz_ratecheck);
2834 
2835 	/* Count the number of duplicate names. */
2836 	cnt.name = arg->name;
2837 	cnt.count = 0;
2838 	zone_foreach(zone_count, &cnt);
2839 	zone->uz_namecnt = cnt.count;
2840 	ZONE_CROSS_LOCK_INIT(zone);
2841 
2842 	for (i = 0; i < vm_ndomains; i++) {
2843 		zdom = ZDOM_GET(zone, i);
2844 		ZDOM_LOCK_INIT(zone, zdom, (arg->flags & UMA_ZONE_MTXCLASS));
2845 		STAILQ_INIT(&zdom->uzd_buckets);
2846 	}
2847 
2848 #if defined(INVARIANTS) && !defined(KASAN) && !defined(KMSAN)
2849 	if (arg->uminit == trash_init && arg->fini == trash_fini)
2850 		zone->uz_flags |= UMA_ZFLAG_TRASH | UMA_ZFLAG_CTORDTOR;
2851 #elif defined(KASAN)
2852 	if ((arg->flags & (UMA_ZONE_NOFREE | UMA_ZFLAG_CACHE)) != 0)
2853 		arg->flags |= UMA_ZONE_NOKASAN;
2854 #endif
2855 
2856 	/*
2857 	 * This is a pure cache zone, no kegs.
2858 	 */
2859 	if (arg->import) {
2860 		KASSERT((arg->flags & UMA_ZFLAG_CACHE) != 0,
2861 		    ("zone_ctor: Import specified for non-cache zone."));
2862 		zone->uz_flags = arg->flags;
2863 		zone->uz_size = arg->size;
2864 		zone->uz_import = arg->import;
2865 		zone->uz_release = arg->release;
2866 		zone->uz_arg = arg->arg;
2867 #ifdef NUMA
2868 		/*
2869 		 * Cache zones are round-robin unless a policy is
2870 		 * specified because they may have incompatible
2871 		 * constraints.
2872 		 */
2873 		if ((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) == 0)
2874 			zone->uz_flags |= UMA_ZONE_ROUNDROBIN;
2875 #endif
2876 		rw_wlock(&uma_rwlock);
2877 		LIST_INSERT_HEAD(&uma_cachezones, zone, uz_link);
2878 		rw_wunlock(&uma_rwlock);
2879 		goto out;
2880 	}
2881 
2882 	/*
2883 	 * Use the regular zone/keg/slab allocator.
2884 	 */
2885 	zone->uz_import = zone_import;
2886 	zone->uz_release = zone_release;
2887 	zone->uz_arg = zone;
2888 	keg = arg->keg;
2889 
2890 	if (arg->flags & UMA_ZONE_SECONDARY) {
2891 		KASSERT((zone->uz_flags & UMA_ZONE_SECONDARY) == 0,
2892 		    ("Secondary zone requested UMA_ZFLAG_INTERNAL"));
2893 		KASSERT(arg->keg != NULL, ("Secondary zone on zero'd keg"));
2894 		zone->uz_init = arg->uminit;
2895 		zone->uz_fini = arg->fini;
2896 		zone->uz_flags |= UMA_ZONE_SECONDARY;
2897 		rw_wlock(&uma_rwlock);
2898 		ZONE_LOCK(zone);
2899 		LIST_FOREACH(z, &keg->uk_zones, uz_link) {
2900 			if (LIST_NEXT(z, uz_link) == NULL) {
2901 				LIST_INSERT_AFTER(z, zone, uz_link);
2902 				break;
2903 			}
2904 		}
2905 		ZONE_UNLOCK(zone);
2906 		rw_wunlock(&uma_rwlock);
2907 	} else if (keg == NULL) {
2908 		if ((keg = uma_kcreate(zone, arg->size, arg->uminit, arg->fini,
2909 		    arg->align, arg->flags)) == NULL)
2910 			return (ENOMEM);
2911 	} else {
2912 		struct uma_kctor_args karg;
2913 		int error;
2914 
2915 		/* We should only be here from uma_startup() */
2916 		karg.size = arg->size;
2917 		karg.uminit = arg->uminit;
2918 		karg.fini = arg->fini;
2919 		karg.align = arg->align;
2920 		karg.flags = (arg->flags & ~UMA_ZONE_SMR);
2921 		karg.zone = zone;
2922 		error = keg_ctor(arg->keg, sizeof(struct uma_keg), &karg,
2923 		    flags);
2924 		if (error)
2925 			return (error);
2926 	}
2927 
2928 	/* Inherit properties from the keg. */
2929 	zone->uz_keg = keg;
2930 	zone->uz_size = keg->uk_size;
2931 	zone->uz_flags |= (keg->uk_flags &
2932 	    (UMA_ZONE_INHERIT | UMA_ZFLAG_INHERIT));
2933 
2934 out:
2935 	if (booted >= BOOT_PCPU) {
2936 		zone_alloc_counters(zone, NULL);
2937 		if (booted >= BOOT_RUNNING)
2938 			zone_alloc_sysctl(zone, NULL);
2939 	} else {
2940 		zone->uz_allocs = EARLY_COUNTER;
2941 		zone->uz_frees = EARLY_COUNTER;
2942 		zone->uz_fails = EARLY_COUNTER;
2943 	}
2944 
2945 	/* Caller requests a private SMR context. */
2946 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0)
2947 		zone->uz_smr = smr_create(zone->uz_name, 0, 0);
2948 
2949 	KASSERT((arg->flags & (UMA_ZONE_MAXBUCKET | UMA_ZONE_NOBUCKET)) !=
2950 	    (UMA_ZONE_MAXBUCKET | UMA_ZONE_NOBUCKET),
2951 	    ("Invalid zone flag combination"));
2952 	if (arg->flags & UMA_ZFLAG_INTERNAL)
2953 		zone->uz_bucket_size_max = zone->uz_bucket_size = 0;
2954 	if ((arg->flags & UMA_ZONE_MAXBUCKET) != 0)
2955 		zone->uz_bucket_size = BUCKET_MAX;
2956 	else if ((arg->flags & UMA_ZONE_NOBUCKET) != 0)
2957 		zone->uz_bucket_size = 0;
2958 	else
2959 		zone->uz_bucket_size = bucket_select(zone->uz_size);
2960 	zone->uz_bucket_size_min = zone->uz_bucket_size;
2961 	if (zone->uz_dtor != NULL || zone->uz_ctor != NULL)
2962 		zone->uz_flags |= UMA_ZFLAG_CTORDTOR;
2963 	zone_update_caches(zone);
2964 
2965 	return (0);
2966 }
2967 
2968 /*
2969  * Keg header dtor.  This frees all data, destroys locks, frees the hash
2970  * table and removes the keg from the global list.
2971  *
2972  * Arguments/Returns follow uma_dtor specifications
2973  *	udata  unused
2974  */
2975 static void
2976 keg_dtor(void *arg, int size, void *udata)
2977 {
2978 	uma_keg_t keg;
2979 	uint32_t free, pages;
2980 	int i;
2981 
2982 	keg = (uma_keg_t)arg;
2983 	free = pages = 0;
2984 	for (i = 0; i < vm_ndomains; i++) {
2985 		free += keg->uk_domain[i].ud_free_items;
2986 		pages += keg->uk_domain[i].ud_pages;
2987 		KEG_LOCK_FINI(keg, i);
2988 	}
2989 	if (pages != 0)
2990 		printf("Freed UMA keg (%s) was not empty (%u items). "
2991 		    " Lost %u pages of memory.\n",
2992 		    keg->uk_name ? keg->uk_name : "",
2993 		    pages / keg->uk_ppera * keg->uk_ipers - free, pages);
2994 
2995 	hash_free(&keg->uk_hash);
2996 }
2997 
2998 /*
2999  * Zone header dtor.
3000  *
3001  * Arguments/Returns follow uma_dtor specifications
3002  *	udata  unused
3003  */
3004 static void
3005 zone_dtor(void *arg, int size, void *udata)
3006 {
3007 	uma_zone_t zone;
3008 	uma_keg_t keg;
3009 	int i;
3010 
3011 	zone = (uma_zone_t)arg;
3012 
3013 	sysctl_remove_oid(zone->uz_oid, 1, 1);
3014 
3015 	if (!(zone->uz_flags & UMA_ZFLAG_INTERNAL))
3016 		cache_drain(zone);
3017 
3018 	rw_wlock(&uma_rwlock);
3019 	LIST_REMOVE(zone, uz_link);
3020 	rw_wunlock(&uma_rwlock);
3021 	if ((zone->uz_flags & (UMA_ZONE_SECONDARY | UMA_ZFLAG_CACHE)) == 0) {
3022 		keg = zone->uz_keg;
3023 		keg->uk_reserve = 0;
3024 	}
3025 	zone_reclaim(zone, UMA_ANYDOMAIN, M_WAITOK, true);
3026 
3027 	/*
3028 	 * We only destroy kegs from non secondary/non cache zones.
3029 	 */
3030 	if ((zone->uz_flags & (UMA_ZONE_SECONDARY | UMA_ZFLAG_CACHE)) == 0) {
3031 		keg = zone->uz_keg;
3032 		rw_wlock(&uma_rwlock);
3033 		LIST_REMOVE(keg, uk_link);
3034 		rw_wunlock(&uma_rwlock);
3035 		zone_free_item(kegs, keg, NULL, SKIP_NONE);
3036 	}
3037 	counter_u64_free(zone->uz_allocs);
3038 	counter_u64_free(zone->uz_frees);
3039 	counter_u64_free(zone->uz_fails);
3040 	counter_u64_free(zone->uz_xdomain);
3041 	free(zone->uz_ctlname, M_UMA);
3042 	for (i = 0; i < vm_ndomains; i++)
3043 		ZDOM_LOCK_FINI(ZDOM_GET(zone, i));
3044 	ZONE_CROSS_LOCK_FINI(zone);
3045 }
3046 
3047 static void
3048 zone_foreach_unlocked(void (*zfunc)(uma_zone_t, void *arg), void *arg)
3049 {
3050 	uma_keg_t keg;
3051 	uma_zone_t zone;
3052 
3053 	LIST_FOREACH(keg, &uma_kegs, uk_link) {
3054 		LIST_FOREACH(zone, &keg->uk_zones, uz_link)
3055 			zfunc(zone, arg);
3056 	}
3057 	LIST_FOREACH(zone, &uma_cachezones, uz_link)
3058 		zfunc(zone, arg);
3059 }
3060 
3061 /*
3062  * Traverses every zone in the system and calls a callback
3063  *
3064  * Arguments:
3065  *	zfunc  A pointer to a function which accepts a zone
3066  *		as an argument.
3067  *
3068  * Returns:
3069  *	Nothing
3070  */
3071 static void
3072 zone_foreach(void (*zfunc)(uma_zone_t, void *arg), void *arg)
3073 {
3074 
3075 	rw_rlock(&uma_rwlock);
3076 	zone_foreach_unlocked(zfunc, arg);
3077 	rw_runlock(&uma_rwlock);
3078 }
3079 
3080 /*
3081  * Initialize the kernel memory allocator.  This is done after pages can be
3082  * allocated but before general KVA is available.
3083  */
3084 void
3085 uma_startup1(vm_offset_t virtual_avail)
3086 {
3087 	struct uma_zctor_args args;
3088 	size_t ksize, zsize, size;
3089 	uma_keg_t primarykeg;
3090 	uintptr_t m;
3091 	int domain;
3092 	uint8_t pflag;
3093 
3094 	bootstart = bootmem = virtual_avail;
3095 
3096 	rw_init(&uma_rwlock, "UMA lock");
3097 	sx_init(&uma_reclaim_lock, "umareclaim");
3098 
3099 	ksize = sizeof(struct uma_keg) +
3100 	    (sizeof(struct uma_domain) * vm_ndomains);
3101 	ksize = roundup(ksize, UMA_SUPER_ALIGN);
3102 	zsize = sizeof(struct uma_zone) +
3103 	    (sizeof(struct uma_cache) * (mp_maxid + 1)) +
3104 	    (sizeof(struct uma_zone_domain) * vm_ndomains);
3105 	zsize = roundup(zsize, UMA_SUPER_ALIGN);
3106 
3107 	/* Allocate the zone of zones, zone of kegs, and zone of zones keg. */
3108 	size = (zsize * 2) + ksize;
3109 	for (domain = 0; domain < vm_ndomains; domain++) {
3110 		m = (uintptr_t)startup_alloc(NULL, size, domain, &pflag,
3111 		    M_NOWAIT | M_ZERO);
3112 		if (m != 0)
3113 			break;
3114 	}
3115 	zones = (uma_zone_t)m;
3116 	m += zsize;
3117 	kegs = (uma_zone_t)m;
3118 	m += zsize;
3119 	primarykeg = (uma_keg_t)m;
3120 
3121 	/* "manually" create the initial zone */
3122 	memset(&args, 0, sizeof(args));
3123 	args.name = "UMA Kegs";
3124 	args.size = ksize;
3125 	args.ctor = keg_ctor;
3126 	args.dtor = keg_dtor;
3127 	args.uminit = zero_init;
3128 	args.fini = NULL;
3129 	args.keg = primarykeg;
3130 	args.align = UMA_SUPER_ALIGN - 1;
3131 	args.flags = UMA_ZFLAG_INTERNAL;
3132 	zone_ctor(kegs, zsize, &args, M_WAITOK);
3133 
3134 	args.name = "UMA Zones";
3135 	args.size = zsize;
3136 	args.ctor = zone_ctor;
3137 	args.dtor = zone_dtor;
3138 	args.uminit = zero_init;
3139 	args.fini = NULL;
3140 	args.keg = NULL;
3141 	args.align = UMA_SUPER_ALIGN - 1;
3142 	args.flags = UMA_ZFLAG_INTERNAL;
3143 	zone_ctor(zones, zsize, &args, M_WAITOK);
3144 
3145 	/* Now make zones for slab headers */
3146 	slabzones[0] = uma_zcreate("UMA Slabs 0", SLABZONE0_SIZE,
3147 	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
3148 	slabzones[1] = uma_zcreate("UMA Slabs 1", SLABZONE1_SIZE,
3149 	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
3150 
3151 	hashzone = uma_zcreate("UMA Hash",
3152 	    sizeof(struct slabhead *) * UMA_HASH_SIZE_INIT,
3153 	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
3154 
3155 	bucket_init();
3156 	smr_init();
3157 }
3158 
3159 #ifndef UMA_MD_SMALL_ALLOC
3160 extern void vm_radix_reserve_kva(void);
3161 #endif
3162 
3163 /*
3164  * Advertise the availability of normal kva allocations and switch to
3165  * the default back-end allocator.  Marks the KVA we consumed on startup
3166  * as used in the map.
3167  */
3168 void
3169 uma_startup2(void)
3170 {
3171 
3172 	if (bootstart != bootmem) {
3173 		vm_map_lock(kernel_map);
3174 		(void)vm_map_insert(kernel_map, NULL, 0, bootstart, bootmem,
3175 		    VM_PROT_RW, VM_PROT_RW, MAP_NOFAULT);
3176 		vm_map_unlock(kernel_map);
3177 	}
3178 
3179 #ifndef UMA_MD_SMALL_ALLOC
3180 	/* Set up radix zone to use noobj_alloc. */
3181 	vm_radix_reserve_kva();
3182 #endif
3183 
3184 	booted = BOOT_KVA;
3185 	zone_foreach_unlocked(zone_kva_available, NULL);
3186 	bucket_enable();
3187 }
3188 
3189 /*
3190  * Allocate counters as early as possible so that boot-time allocations are
3191  * accounted more precisely.
3192  */
3193 static void
3194 uma_startup_pcpu(void *arg __unused)
3195 {
3196 
3197 	zone_foreach_unlocked(zone_alloc_counters, NULL);
3198 	booted = BOOT_PCPU;
3199 }
3200 SYSINIT(uma_startup_pcpu, SI_SUB_COUNTER, SI_ORDER_ANY, uma_startup_pcpu, NULL);
3201 
3202 /*
3203  * Finish our initialization steps.
3204  */
3205 static void
3206 uma_startup3(void *arg __unused)
3207 {
3208 
3209 #ifdef INVARIANTS
3210 	TUNABLE_INT_FETCH("vm.debug.divisor", &dbg_divisor);
3211 	uma_dbg_cnt = counter_u64_alloc(M_WAITOK);
3212 	uma_skip_cnt = counter_u64_alloc(M_WAITOK);
3213 #endif
3214 	zone_foreach_unlocked(zone_alloc_sysctl, NULL);
3215 	booted = BOOT_RUNNING;
3216 
3217 	EVENTHANDLER_REGISTER(shutdown_post_sync, uma_shutdown, NULL,
3218 	    EVENTHANDLER_PRI_FIRST);
3219 }
3220 SYSINIT(uma_startup3, SI_SUB_VM_CONF, SI_ORDER_SECOND, uma_startup3, NULL);
3221 
3222 static void
3223 uma_startup4(void *arg __unused)
3224 {
3225 	TIMEOUT_TASK_INIT(taskqueue_thread, &uma_timeout_task, 0, uma_timeout,
3226 	    NULL);
3227 	taskqueue_enqueue_timeout(taskqueue_thread, &uma_timeout_task,
3228 	    UMA_TIMEOUT * hz);
3229 }
3230 SYSINIT(uma_startup4, SI_SUB_TASKQ, SI_ORDER_ANY, uma_startup4, NULL);
3231 
3232 static void
3233 uma_shutdown(void)
3234 {
3235 
3236 	booted = BOOT_SHUTDOWN;
3237 }
3238 
3239 static uma_keg_t
3240 uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit, uma_fini fini,
3241 		int align, uint32_t flags)
3242 {
3243 	struct uma_kctor_args args;
3244 
3245 	args.size = size;
3246 	args.uminit = uminit;
3247 	args.fini = fini;
3248 	args.align = (align == UMA_ALIGN_CACHE) ? uma_align_cache : align;
3249 	args.flags = flags;
3250 	args.zone = zone;
3251 	return (zone_alloc_item(kegs, &args, UMA_ANYDOMAIN, M_WAITOK));
3252 }
3253 
3254 /* Public functions */
3255 /* See uma.h */
3256 void
3257 uma_set_align(int align)
3258 {
3259 
3260 	if (align != UMA_ALIGN_CACHE)
3261 		uma_align_cache = align;
3262 }
3263 
3264 /* See uma.h */
3265 uma_zone_t
3266 uma_zcreate(const char *name, size_t size, uma_ctor ctor, uma_dtor dtor,
3267 		uma_init uminit, uma_fini fini, int align, uint32_t flags)
3268 
3269 {
3270 	struct uma_zctor_args args;
3271 	uma_zone_t res;
3272 
3273 	KASSERT(powerof2(align + 1), ("invalid zone alignment %d for \"%s\"",
3274 	    align, name));
3275 
3276 	/* This stuff is essential for the zone ctor */
3277 	memset(&args, 0, sizeof(args));
3278 	args.name = name;
3279 	args.size = size;
3280 	args.ctor = ctor;
3281 	args.dtor = dtor;
3282 	args.uminit = uminit;
3283 	args.fini = fini;
3284 #if defined(INVARIANTS) && !defined(KASAN) && !defined(KMSAN)
3285 	/*
3286 	 * Inject procedures which check for memory use after free if we are
3287 	 * allowed to scramble the memory while it is not allocated.  This
3288 	 * requires that: UMA is actually able to access the memory, no init
3289 	 * or fini procedures, no dependency on the initial value of the
3290 	 * memory, and no (legitimate) use of the memory after free.  Note,
3291 	 * the ctor and dtor do not need to be empty.
3292 	 */
3293 	if ((!(flags & (UMA_ZONE_ZINIT | UMA_ZONE_NOTOUCH |
3294 	    UMA_ZONE_NOFREE))) && uminit == NULL && fini == NULL) {
3295 		args.uminit = trash_init;
3296 		args.fini = trash_fini;
3297 	}
3298 #endif
3299 	args.align = align;
3300 	args.flags = flags;
3301 	args.keg = NULL;
3302 
3303 	sx_xlock(&uma_reclaim_lock);
3304 	res = zone_alloc_item(zones, &args, UMA_ANYDOMAIN, M_WAITOK);
3305 	sx_xunlock(&uma_reclaim_lock);
3306 
3307 	return (res);
3308 }
3309 
3310 /* See uma.h */
3311 uma_zone_t
3312 uma_zsecond_create(const char *name, uma_ctor ctor, uma_dtor dtor,
3313     uma_init zinit, uma_fini zfini, uma_zone_t primary)
3314 {
3315 	struct uma_zctor_args args;
3316 	uma_keg_t keg;
3317 	uma_zone_t res;
3318 
3319 	keg = primary->uz_keg;
3320 	memset(&args, 0, sizeof(args));
3321 	args.name = name;
3322 	args.size = keg->uk_size;
3323 	args.ctor = ctor;
3324 	args.dtor = dtor;
3325 	args.uminit = zinit;
3326 	args.fini = zfini;
3327 	args.align = keg->uk_align;
3328 	args.flags = keg->uk_flags | UMA_ZONE_SECONDARY;
3329 	args.keg = keg;
3330 
3331 	sx_xlock(&uma_reclaim_lock);
3332 	res = zone_alloc_item(zones, &args, UMA_ANYDOMAIN, M_WAITOK);
3333 	sx_xunlock(&uma_reclaim_lock);
3334 
3335 	return (res);
3336 }
3337 
3338 /* See uma.h */
3339 uma_zone_t
3340 uma_zcache_create(const char *name, int size, uma_ctor ctor, uma_dtor dtor,
3341     uma_init zinit, uma_fini zfini, uma_import zimport, uma_release zrelease,
3342     void *arg, int flags)
3343 {
3344 	struct uma_zctor_args args;
3345 
3346 	memset(&args, 0, sizeof(args));
3347 	args.name = name;
3348 	args.size = size;
3349 	args.ctor = ctor;
3350 	args.dtor = dtor;
3351 	args.uminit = zinit;
3352 	args.fini = zfini;
3353 	args.import = zimport;
3354 	args.release = zrelease;
3355 	args.arg = arg;
3356 	args.align = 0;
3357 	args.flags = flags | UMA_ZFLAG_CACHE;
3358 
3359 	return (zone_alloc_item(zones, &args, UMA_ANYDOMAIN, M_WAITOK));
3360 }
3361 
3362 /* See uma.h */
3363 void
3364 uma_zdestroy(uma_zone_t zone)
3365 {
3366 
3367 	/*
3368 	 * Large slabs are expensive to reclaim, so don't bother doing
3369 	 * unnecessary work if we're shutting down.
3370 	 */
3371 	if (booted == BOOT_SHUTDOWN &&
3372 	    zone->uz_fini == NULL && zone->uz_release == zone_release)
3373 		return;
3374 	sx_xlock(&uma_reclaim_lock);
3375 	zone_free_item(zones, zone, NULL, SKIP_NONE);
3376 	sx_xunlock(&uma_reclaim_lock);
3377 }
3378 
3379 void
3380 uma_zwait(uma_zone_t zone)
3381 {
3382 
3383 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0)
3384 		uma_zfree_smr(zone, uma_zalloc_smr(zone, M_WAITOK));
3385 	else if ((zone->uz_flags & UMA_ZONE_PCPU) != 0)
3386 		uma_zfree_pcpu(zone, uma_zalloc_pcpu(zone, M_WAITOK));
3387 	else
3388 		uma_zfree(zone, uma_zalloc(zone, M_WAITOK));
3389 }
3390 
3391 void *
3392 uma_zalloc_pcpu_arg(uma_zone_t zone, void *udata, int flags)
3393 {
3394 	void *item, *pcpu_item;
3395 #ifdef SMP
3396 	int i;
3397 
3398 	MPASS(zone->uz_flags & UMA_ZONE_PCPU);
3399 #endif
3400 	item = uma_zalloc_arg(zone, udata, flags & ~M_ZERO);
3401 	if (item == NULL)
3402 		return (NULL);
3403 	pcpu_item = zpcpu_base_to_offset(item);
3404 	if (flags & M_ZERO) {
3405 #ifdef SMP
3406 		for (i = 0; i <= mp_maxid; i++)
3407 			bzero(zpcpu_get_cpu(pcpu_item, i), zone->uz_size);
3408 #else
3409 		bzero(item, zone->uz_size);
3410 #endif
3411 	}
3412 	return (pcpu_item);
3413 }
3414 
3415 /*
3416  * A stub while both regular and pcpu cases are identical.
3417  */
3418 void
3419 uma_zfree_pcpu_arg(uma_zone_t zone, void *pcpu_item, void *udata)
3420 {
3421 	void *item;
3422 
3423 #ifdef SMP
3424 	MPASS(zone->uz_flags & UMA_ZONE_PCPU);
3425 #endif
3426 
3427         /* uma_zfree_pcu_*(..., NULL) does nothing, to match free(9). */
3428         if (pcpu_item == NULL)
3429                 return;
3430 
3431 	item = zpcpu_offset_to_base(pcpu_item);
3432 	uma_zfree_arg(zone, item, udata);
3433 }
3434 
3435 static inline void *
3436 item_ctor(uma_zone_t zone, int uz_flags, int size, void *udata, int flags,
3437     void *item)
3438 {
3439 #ifdef INVARIANTS
3440 	bool skipdbg;
3441 #endif
3442 
3443 	kasan_mark_item_valid(zone, item);
3444 	kmsan_mark_item_uninitialized(zone, item);
3445 
3446 #ifdef INVARIANTS
3447 	skipdbg = uma_dbg_zskip(zone, item);
3448 	if (!skipdbg && (uz_flags & UMA_ZFLAG_TRASH) != 0 &&
3449 	    zone->uz_ctor != trash_ctor)
3450 		trash_ctor(item, size, udata, flags);
3451 #endif
3452 
3453 	/* Check flags before loading ctor pointer. */
3454 	if (__predict_false((uz_flags & UMA_ZFLAG_CTORDTOR) != 0) &&
3455 	    __predict_false(zone->uz_ctor != NULL) &&
3456 	    zone->uz_ctor(item, size, udata, flags) != 0) {
3457 		counter_u64_add(zone->uz_fails, 1);
3458 		zone_free_item(zone, item, udata, SKIP_DTOR | SKIP_CNT);
3459 		return (NULL);
3460 	}
3461 #ifdef INVARIANTS
3462 	if (!skipdbg)
3463 		uma_dbg_alloc(zone, NULL, item);
3464 #endif
3465 	if (__predict_false(flags & M_ZERO))
3466 		return (memset(item, 0, size));
3467 
3468 	return (item);
3469 }
3470 
3471 static inline void
3472 item_dtor(uma_zone_t zone, void *item, int size, void *udata,
3473     enum zfreeskip skip)
3474 {
3475 #ifdef INVARIANTS
3476 	bool skipdbg;
3477 
3478 	skipdbg = uma_dbg_zskip(zone, item);
3479 	if (skip == SKIP_NONE && !skipdbg) {
3480 		if ((zone->uz_flags & UMA_ZONE_MALLOC) != 0)
3481 			uma_dbg_free(zone, udata, item);
3482 		else
3483 			uma_dbg_free(zone, NULL, item);
3484 	}
3485 #endif
3486 	if (__predict_true(skip < SKIP_DTOR)) {
3487 		if (zone->uz_dtor != NULL)
3488 			zone->uz_dtor(item, size, udata);
3489 #ifdef INVARIANTS
3490 		if (!skipdbg && (zone->uz_flags & UMA_ZFLAG_TRASH) != 0 &&
3491 		    zone->uz_dtor != trash_dtor)
3492 			trash_dtor(item, size, udata);
3493 #endif
3494 	}
3495 	kasan_mark_item_invalid(zone, item);
3496 }
3497 
3498 #ifdef NUMA
3499 static int
3500 item_domain(void *item)
3501 {
3502 	int domain;
3503 
3504 	domain = vm_phys_domain(vtophys(item));
3505 	KASSERT(domain >= 0 && domain < vm_ndomains,
3506 	    ("%s: unknown domain for item %p", __func__, item));
3507 	return (domain);
3508 }
3509 #endif
3510 
3511 #if defined(INVARIANTS) || defined(DEBUG_MEMGUARD) || defined(WITNESS)
3512 #if defined(INVARIANTS) && (defined(DDB) || defined(STACK))
3513 #include <sys/stack.h>
3514 #endif
3515 #define	UMA_ZALLOC_DEBUG
3516 static int
3517 uma_zalloc_debug(uma_zone_t zone, void **itemp, void *udata, int flags)
3518 {
3519 	int error;
3520 
3521 	error = 0;
3522 #ifdef WITNESS
3523 	if (flags & M_WAITOK) {
3524 		WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
3525 		    "uma_zalloc_debug: zone \"%s\"", zone->uz_name);
3526 	}
3527 #endif
3528 
3529 #ifdef INVARIANTS
3530 	KASSERT((flags & M_EXEC) == 0,
3531 	    ("uma_zalloc_debug: called with M_EXEC"));
3532 	KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
3533 	    ("uma_zalloc_debug: called within spinlock or critical section"));
3534 	KASSERT((zone->uz_flags & UMA_ZONE_PCPU) == 0 || (flags & M_ZERO) == 0,
3535 	    ("uma_zalloc_debug: allocating from a pcpu zone with M_ZERO"));
3536 
3537 	_Static_assert(M_NOWAIT != 0 && M_WAITOK != 0,
3538 	    "M_NOWAIT and M_WAITOK must be non-zero for this assertion:");
3539 #if 0
3540 	/*
3541 	 * Give the #elif clause time to find problems, then remove it
3542 	 * and enable this.  (Remove <sys/stack.h> above, too.)
3543 	 */
3544 	KASSERT((flags & (M_NOWAIT|M_WAITOK)) == M_NOWAIT ||
3545 	    (flags & (M_NOWAIT|M_WAITOK)) == M_WAITOK,
3546 	    ("uma_zalloc_debug: must pass one of M_NOWAIT or M_WAITOK"));
3547 #elif defined(DDB) || defined(STACK)
3548 	if (__predict_false((flags & (M_NOWAIT|M_WAITOK)) != M_NOWAIT &&
3549 	    (flags & (M_NOWAIT|M_WAITOK)) != M_WAITOK)) {
3550 		static int stack_count;
3551 		struct stack st;
3552 
3553 		if (stack_count < 10) {
3554 			++stack_count;
3555 			printf("uma_zalloc* called with bad WAIT flags:\n");
3556 			stack_save(&st);
3557 			stack_print(&st);
3558 		}
3559 	}
3560 #endif
3561 #endif
3562 
3563 #ifdef DEBUG_MEMGUARD
3564 	if ((zone->uz_flags & (UMA_ZONE_SMR | UMA_ZFLAG_CACHE)) == 0 &&
3565 	    memguard_cmp_zone(zone)) {
3566 		void *item;
3567 		item = memguard_alloc(zone->uz_size, flags);
3568 		if (item != NULL) {
3569 			error = EJUSTRETURN;
3570 			if (zone->uz_init != NULL &&
3571 			    zone->uz_init(item, zone->uz_size, flags) != 0) {
3572 				*itemp = NULL;
3573 				return (error);
3574 			}
3575 			if (zone->uz_ctor != NULL &&
3576 			    zone->uz_ctor(item, zone->uz_size, udata,
3577 			    flags) != 0) {
3578 				counter_u64_add(zone->uz_fails, 1);
3579 				if (zone->uz_fini != NULL)
3580 					zone->uz_fini(item, zone->uz_size);
3581 				*itemp = NULL;
3582 				return (error);
3583 			}
3584 			*itemp = item;
3585 			return (error);
3586 		}
3587 		/* This is unfortunate but should not be fatal. */
3588 	}
3589 #endif
3590 	return (error);
3591 }
3592 
3593 static int
3594 uma_zfree_debug(uma_zone_t zone, void *item, void *udata)
3595 {
3596 	KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
3597 	    ("uma_zfree_debug: called with spinlock or critical section held"));
3598 
3599 #ifdef DEBUG_MEMGUARD
3600 	if ((zone->uz_flags & (UMA_ZONE_SMR | UMA_ZFLAG_CACHE)) == 0 &&
3601 	    is_memguard_addr(item)) {
3602 		if (zone->uz_dtor != NULL)
3603 			zone->uz_dtor(item, zone->uz_size, udata);
3604 		if (zone->uz_fini != NULL)
3605 			zone->uz_fini(item, zone->uz_size);
3606 		memguard_free(item);
3607 		return (EJUSTRETURN);
3608 	}
3609 #endif
3610 	return (0);
3611 }
3612 #endif
3613 
3614 static inline void *
3615 cache_alloc_item(uma_zone_t zone, uma_cache_t cache, uma_cache_bucket_t bucket,
3616     void *udata, int flags)
3617 {
3618 	void *item;
3619 	int size, uz_flags;
3620 
3621 	item = cache_bucket_pop(cache, bucket);
3622 	size = cache_uz_size(cache);
3623 	uz_flags = cache_uz_flags(cache);
3624 	critical_exit();
3625 	return (item_ctor(zone, uz_flags, size, udata, flags, item));
3626 }
3627 
3628 static __noinline void *
3629 cache_alloc_retry(uma_zone_t zone, uma_cache_t cache, void *udata, int flags)
3630 {
3631 	uma_cache_bucket_t bucket;
3632 	int domain;
3633 
3634 	while (cache_alloc(zone, cache, udata, flags)) {
3635 		cache = &zone->uz_cpu[curcpu];
3636 		bucket = &cache->uc_allocbucket;
3637 		if (__predict_false(bucket->ucb_cnt == 0))
3638 			continue;
3639 		return (cache_alloc_item(zone, cache, bucket, udata, flags));
3640 	}
3641 	critical_exit();
3642 
3643 	/*
3644 	 * We can not get a bucket so try to return a single item.
3645 	 */
3646 	if (zone->uz_flags & UMA_ZONE_FIRSTTOUCH)
3647 		domain = PCPU_GET(domain);
3648 	else
3649 		domain = UMA_ANYDOMAIN;
3650 	return (zone_alloc_item(zone, udata, domain, flags));
3651 }
3652 
3653 /* See uma.h */
3654 void *
3655 uma_zalloc_smr(uma_zone_t zone, int flags)
3656 {
3657 	uma_cache_bucket_t bucket;
3658 	uma_cache_t cache;
3659 
3660 	CTR3(KTR_UMA, "uma_zalloc_smr zone %s(%p) flags %d", zone->uz_name,
3661 	    zone, flags);
3662 
3663 #ifdef UMA_ZALLOC_DEBUG
3664 	void *item;
3665 
3666 	KASSERT((zone->uz_flags & UMA_ZONE_SMR) != 0,
3667 	    ("uma_zalloc_arg: called with non-SMR zone."));
3668 	if (uma_zalloc_debug(zone, &item, NULL, flags) == EJUSTRETURN)
3669 		return (item);
3670 #endif
3671 
3672 	critical_enter();
3673 	cache = &zone->uz_cpu[curcpu];
3674 	bucket = &cache->uc_allocbucket;
3675 	if (__predict_false(bucket->ucb_cnt == 0))
3676 		return (cache_alloc_retry(zone, cache, NULL, flags));
3677 	return (cache_alloc_item(zone, cache, bucket, NULL, flags));
3678 }
3679 
3680 /* See uma.h */
3681 void *
3682 uma_zalloc_arg(uma_zone_t zone, void *udata, int flags)
3683 {
3684 	uma_cache_bucket_t bucket;
3685 	uma_cache_t cache;
3686 
3687 	/* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
3688 	random_harvest_fast_uma(&zone, sizeof(zone), RANDOM_UMA);
3689 
3690 	/* This is the fast path allocation */
3691 	CTR3(KTR_UMA, "uma_zalloc_arg zone %s(%p) flags %d", zone->uz_name,
3692 	    zone, flags);
3693 
3694 #ifdef UMA_ZALLOC_DEBUG
3695 	void *item;
3696 
3697 	KASSERT((zone->uz_flags & UMA_ZONE_SMR) == 0,
3698 	    ("uma_zalloc_arg: called with SMR zone."));
3699 	if (uma_zalloc_debug(zone, &item, udata, flags) == EJUSTRETURN)
3700 		return (item);
3701 #endif
3702 
3703 	/*
3704 	 * If possible, allocate from the per-CPU cache.  There are two
3705 	 * requirements for safe access to the per-CPU cache: (1) the thread
3706 	 * accessing the cache must not be preempted or yield during access,
3707 	 * and (2) the thread must not migrate CPUs without switching which
3708 	 * cache it accesses.  We rely on a critical section to prevent
3709 	 * preemption and migration.  We release the critical section in
3710 	 * order to acquire the zone mutex if we are unable to allocate from
3711 	 * the current cache; when we re-acquire the critical section, we
3712 	 * must detect and handle migration if it has occurred.
3713 	 */
3714 	critical_enter();
3715 	cache = &zone->uz_cpu[curcpu];
3716 	bucket = &cache->uc_allocbucket;
3717 	if (__predict_false(bucket->ucb_cnt == 0))
3718 		return (cache_alloc_retry(zone, cache, udata, flags));
3719 	return (cache_alloc_item(zone, cache, bucket, udata, flags));
3720 }
3721 
3722 /*
3723  * Replenish an alloc bucket and possibly restore an old one.  Called in
3724  * a critical section.  Returns in a critical section.
3725  *
3726  * A false return value indicates an allocation failure.
3727  * A true return value indicates success and the caller should retry.
3728  */
3729 static __noinline bool
3730 cache_alloc(uma_zone_t zone, uma_cache_t cache, void *udata, int flags)
3731 {
3732 	uma_bucket_t bucket;
3733 	int curdomain, domain;
3734 	bool new;
3735 
3736 	CRITICAL_ASSERT(curthread);
3737 
3738 	/*
3739 	 * If we have run out of items in our alloc bucket see
3740 	 * if we can switch with the free bucket.
3741 	 *
3742 	 * SMR Zones can't re-use the free bucket until the sequence has
3743 	 * expired.
3744 	 */
3745 	if ((cache_uz_flags(cache) & UMA_ZONE_SMR) == 0 &&
3746 	    cache->uc_freebucket.ucb_cnt != 0) {
3747 		cache_bucket_swap(&cache->uc_freebucket,
3748 		    &cache->uc_allocbucket);
3749 		return (true);
3750 	}
3751 
3752 	/*
3753 	 * Discard any empty allocation bucket while we hold no locks.
3754 	 */
3755 	bucket = cache_bucket_unload_alloc(cache);
3756 	critical_exit();
3757 
3758 	if (bucket != NULL) {
3759 		KASSERT(bucket->ub_cnt == 0,
3760 		    ("cache_alloc: Entered with non-empty alloc bucket."));
3761 		bucket_free(zone, bucket, udata);
3762 	}
3763 
3764 	/*
3765 	 * Attempt to retrieve the item from the per-CPU cache has failed, so
3766 	 * we must go back to the zone.  This requires the zdom lock, so we
3767 	 * must drop the critical section, then re-acquire it when we go back
3768 	 * to the cache.  Since the critical section is released, we may be
3769 	 * preempted or migrate.  As such, make sure not to maintain any
3770 	 * thread-local state specific to the cache from prior to releasing
3771 	 * the critical section.
3772 	 */
3773 	domain = PCPU_GET(domain);
3774 	if ((cache_uz_flags(cache) & UMA_ZONE_ROUNDROBIN) != 0 ||
3775 	    VM_DOMAIN_EMPTY(domain))
3776 		domain = zone_domain_highest(zone, domain);
3777 	bucket = cache_fetch_bucket(zone, cache, domain);
3778 	if (bucket == NULL && zone->uz_bucket_size != 0 && !bucketdisable) {
3779 		bucket = zone_alloc_bucket(zone, udata, domain, flags);
3780 		new = true;
3781 	} else {
3782 		new = false;
3783 	}
3784 
3785 	CTR3(KTR_UMA, "uma_zalloc: zone %s(%p) bucket zone returned %p",
3786 	    zone->uz_name, zone, bucket);
3787 	if (bucket == NULL) {
3788 		critical_enter();
3789 		return (false);
3790 	}
3791 
3792 	/*
3793 	 * See if we lost the race or were migrated.  Cache the
3794 	 * initialized bucket to make this less likely or claim
3795 	 * the memory directly.
3796 	 */
3797 	critical_enter();
3798 	cache = &zone->uz_cpu[curcpu];
3799 	if (cache->uc_allocbucket.ucb_bucket == NULL &&
3800 	    ((cache_uz_flags(cache) & UMA_ZONE_FIRSTTOUCH) == 0 ||
3801 	    (curdomain = PCPU_GET(domain)) == domain ||
3802 	    VM_DOMAIN_EMPTY(curdomain))) {
3803 		if (new)
3804 			atomic_add_long(&ZDOM_GET(zone, domain)->uzd_imax,
3805 			    bucket->ub_cnt);
3806 		cache_bucket_load_alloc(cache, bucket);
3807 		return (true);
3808 	}
3809 
3810 	/*
3811 	 * We lost the race, release this bucket and start over.
3812 	 */
3813 	critical_exit();
3814 	zone_put_bucket(zone, domain, bucket, udata, !new);
3815 	critical_enter();
3816 
3817 	return (true);
3818 }
3819 
3820 void *
3821 uma_zalloc_domain(uma_zone_t zone, void *udata, int domain, int flags)
3822 {
3823 #ifdef NUMA
3824 	uma_bucket_t bucket;
3825 	uma_zone_domain_t zdom;
3826 	void *item;
3827 #endif
3828 
3829 	/* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
3830 	random_harvest_fast_uma(&zone, sizeof(zone), RANDOM_UMA);
3831 
3832 	/* This is the fast path allocation */
3833 	CTR4(KTR_UMA, "uma_zalloc_domain zone %s(%p) domain %d flags %d",
3834 	    zone->uz_name, zone, domain, flags);
3835 
3836 	KASSERT((zone->uz_flags & UMA_ZONE_SMR) == 0,
3837 	    ("uma_zalloc_domain: called with SMR zone."));
3838 #ifdef NUMA
3839 	KASSERT((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) != 0,
3840 	    ("uma_zalloc_domain: called with non-FIRSTTOUCH zone."));
3841 
3842 	if (vm_ndomains == 1)
3843 		return (uma_zalloc_arg(zone, udata, flags));
3844 
3845 #ifdef UMA_ZALLOC_DEBUG
3846 	if (uma_zalloc_debug(zone, &item, udata, flags) == EJUSTRETURN)
3847 		return (item);
3848 #endif
3849 
3850 	/*
3851 	 * Try to allocate from the bucket cache before falling back to the keg.
3852 	 * We could try harder and attempt to allocate from per-CPU caches or
3853 	 * the per-domain cross-domain buckets, but the complexity is probably
3854 	 * not worth it.  It is more important that frees of previous
3855 	 * cross-domain allocations do not blow up the cache.
3856 	 */
3857 	zdom = zone_domain_lock(zone, domain);
3858 	if ((bucket = zone_fetch_bucket(zone, zdom, false)) != NULL) {
3859 		item = bucket->ub_bucket[bucket->ub_cnt - 1];
3860 #ifdef INVARIANTS
3861 		bucket->ub_bucket[bucket->ub_cnt - 1] = NULL;
3862 #endif
3863 		bucket->ub_cnt--;
3864 		zone_put_bucket(zone, domain, bucket, udata, true);
3865 		item = item_ctor(zone, zone->uz_flags, zone->uz_size, udata,
3866 		    flags, item);
3867 		if (item != NULL) {
3868 			KASSERT(item_domain(item) == domain,
3869 			    ("%s: bucket cache item %p from wrong domain",
3870 			    __func__, item));
3871 			counter_u64_add(zone->uz_allocs, 1);
3872 		}
3873 		return (item);
3874 	}
3875 	ZDOM_UNLOCK(zdom);
3876 	return (zone_alloc_item(zone, udata, domain, flags));
3877 #else
3878 	return (uma_zalloc_arg(zone, udata, flags));
3879 #endif
3880 }
3881 
3882 /*
3883  * Find a slab with some space.  Prefer slabs that are partially used over those
3884  * that are totally full.  This helps to reduce fragmentation.
3885  *
3886  * If 'rr' is 1, search all domains starting from 'domain'.  Otherwise check
3887  * only 'domain'.
3888  */
3889 static uma_slab_t
3890 keg_first_slab(uma_keg_t keg, int domain, bool rr)
3891 {
3892 	uma_domain_t dom;
3893 	uma_slab_t slab;
3894 	int start;
3895 
3896 	KASSERT(domain >= 0 && domain < vm_ndomains,
3897 	    ("keg_first_slab: domain %d out of range", domain));
3898 	KEG_LOCK_ASSERT(keg, domain);
3899 
3900 	slab = NULL;
3901 	start = domain;
3902 	do {
3903 		dom = &keg->uk_domain[domain];
3904 		if ((slab = LIST_FIRST(&dom->ud_part_slab)) != NULL)
3905 			return (slab);
3906 		if ((slab = LIST_FIRST(&dom->ud_free_slab)) != NULL) {
3907 			LIST_REMOVE(slab, us_link);
3908 			dom->ud_free_slabs--;
3909 			LIST_INSERT_HEAD(&dom->ud_part_slab, slab, us_link);
3910 			return (slab);
3911 		}
3912 		if (rr)
3913 			domain = (domain + 1) % vm_ndomains;
3914 	} while (domain != start);
3915 
3916 	return (NULL);
3917 }
3918 
3919 /*
3920  * Fetch an existing slab from a free or partial list.  Returns with the
3921  * keg domain lock held if a slab was found or unlocked if not.
3922  */
3923 static uma_slab_t
3924 keg_fetch_free_slab(uma_keg_t keg, int domain, bool rr, int flags)
3925 {
3926 	uma_slab_t slab;
3927 	uint32_t reserve;
3928 
3929 	/* HASH has a single free list. */
3930 	if ((keg->uk_flags & UMA_ZFLAG_HASH) != 0)
3931 		domain = 0;
3932 
3933 	KEG_LOCK(keg, domain);
3934 	reserve = (flags & M_USE_RESERVE) != 0 ? 0 : keg->uk_reserve;
3935 	if (keg->uk_domain[domain].ud_free_items <= reserve ||
3936 	    (slab = keg_first_slab(keg, domain, rr)) == NULL) {
3937 		KEG_UNLOCK(keg, domain);
3938 		return (NULL);
3939 	}
3940 	return (slab);
3941 }
3942 
3943 static uma_slab_t
3944 keg_fetch_slab(uma_keg_t keg, uma_zone_t zone, int rdomain, const int flags)
3945 {
3946 	struct vm_domainset_iter di;
3947 	uma_slab_t slab;
3948 	int aflags, domain;
3949 	bool rr;
3950 
3951 	KASSERT((flags & (M_WAITOK | M_NOVM)) != (M_WAITOK | M_NOVM),
3952 	    ("%s: invalid flags %#x", __func__, flags));
3953 
3954 restart:
3955 	/*
3956 	 * Use the keg's policy if upper layers haven't already specified a
3957 	 * domain (as happens with first-touch zones).
3958 	 *
3959 	 * To avoid races we run the iterator with the keg lock held, but that
3960 	 * means that we cannot allow the vm_domainset layer to sleep.  Thus,
3961 	 * clear M_WAITOK and handle low memory conditions locally.
3962 	 */
3963 	rr = rdomain == UMA_ANYDOMAIN;
3964 	if (rr) {
3965 		aflags = (flags & ~M_WAITOK) | M_NOWAIT;
3966 		vm_domainset_iter_policy_ref_init(&di, &keg->uk_dr, &domain,
3967 		    &aflags);
3968 	} else {
3969 		aflags = flags;
3970 		domain = rdomain;
3971 	}
3972 
3973 	for (;;) {
3974 		slab = keg_fetch_free_slab(keg, domain, rr, flags);
3975 		if (slab != NULL)
3976 			return (slab);
3977 
3978 		/*
3979 		 * M_NOVM is used to break the recursion that can otherwise
3980 		 * occur if low-level memory management routines use UMA.
3981 		 */
3982 		if ((flags & M_NOVM) == 0) {
3983 			slab = keg_alloc_slab(keg, zone, domain, flags, aflags);
3984 			if (slab != NULL)
3985 				return (slab);
3986 		}
3987 
3988 		if (!rr) {
3989 			if ((flags & M_USE_RESERVE) != 0) {
3990 				/*
3991 				 * Drain reserves from other domains before
3992 				 * giving up or sleeping.  It may be useful to
3993 				 * support per-domain reserves eventually.
3994 				 */
3995 				rdomain = UMA_ANYDOMAIN;
3996 				goto restart;
3997 			}
3998 			if ((flags & M_WAITOK) == 0)
3999 				break;
4000 			vm_wait_domain(domain);
4001 		} else if (vm_domainset_iter_policy(&di, &domain) != 0) {
4002 			if ((flags & M_WAITOK) != 0) {
4003 				vm_wait_doms(&keg->uk_dr.dr_policy->ds_mask, 0);
4004 				goto restart;
4005 			}
4006 			break;
4007 		}
4008 	}
4009 
4010 	/*
4011 	 * We might not have been able to get a slab but another cpu
4012 	 * could have while we were unlocked.  Check again before we
4013 	 * fail.
4014 	 */
4015 	if ((slab = keg_fetch_free_slab(keg, domain, rr, flags)) != NULL)
4016 		return (slab);
4017 
4018 	return (NULL);
4019 }
4020 
4021 static void *
4022 slab_alloc_item(uma_keg_t keg, uma_slab_t slab)
4023 {
4024 	uma_domain_t dom;
4025 	void *item;
4026 	int freei;
4027 
4028 	KEG_LOCK_ASSERT(keg, slab->us_domain);
4029 
4030 	dom = &keg->uk_domain[slab->us_domain];
4031 	freei = BIT_FFS(keg->uk_ipers, &slab->us_free) - 1;
4032 	BIT_CLR(keg->uk_ipers, freei, &slab->us_free);
4033 	item = slab_item(slab, keg, freei);
4034 	slab->us_freecount--;
4035 	dom->ud_free_items--;
4036 
4037 	/*
4038 	 * Move this slab to the full list.  It must be on the partial list, so
4039 	 * we do not need to update the free slab count.  In particular,
4040 	 * keg_fetch_slab() always returns slabs on the partial list.
4041 	 */
4042 	if (slab->us_freecount == 0) {
4043 		LIST_REMOVE(slab, us_link);
4044 		LIST_INSERT_HEAD(&dom->ud_full_slab, slab, us_link);
4045 	}
4046 
4047 	return (item);
4048 }
4049 
4050 static int
4051 zone_import(void *arg, void **bucket, int max, int domain, int flags)
4052 {
4053 	uma_domain_t dom;
4054 	uma_zone_t zone;
4055 	uma_slab_t slab;
4056 	uma_keg_t keg;
4057 #ifdef NUMA
4058 	int stripe;
4059 #endif
4060 	int i;
4061 
4062 	zone = arg;
4063 	slab = NULL;
4064 	keg = zone->uz_keg;
4065 	/* Try to keep the buckets totally full */
4066 	for (i = 0; i < max; ) {
4067 		if ((slab = keg_fetch_slab(keg, zone, domain, flags)) == NULL)
4068 			break;
4069 #ifdef NUMA
4070 		stripe = howmany(max, vm_ndomains);
4071 #endif
4072 		dom = &keg->uk_domain[slab->us_domain];
4073 		do {
4074 			bucket[i++] = slab_alloc_item(keg, slab);
4075 			if (keg->uk_reserve > 0 &&
4076 			    dom->ud_free_items <= keg->uk_reserve) {
4077 				/*
4078 				 * Avoid depleting the reserve after a
4079 				 * successful item allocation, even if
4080 				 * M_USE_RESERVE is specified.
4081 				 */
4082 				KEG_UNLOCK(keg, slab->us_domain);
4083 				goto out;
4084 			}
4085 #ifdef NUMA
4086 			/*
4087 			 * If the zone is striped we pick a new slab for every
4088 			 * N allocations.  Eliminating this conditional will
4089 			 * instead pick a new domain for each bucket rather
4090 			 * than stripe within each bucket.  The current option
4091 			 * produces more fragmentation and requires more cpu
4092 			 * time but yields better distribution.
4093 			 */
4094 			if ((zone->uz_flags & UMA_ZONE_ROUNDROBIN) != 0 &&
4095 			    vm_ndomains > 1 && --stripe == 0)
4096 				break;
4097 #endif
4098 		} while (slab->us_freecount != 0 && i < max);
4099 		KEG_UNLOCK(keg, slab->us_domain);
4100 
4101 		/* Don't block if we allocated any successfully. */
4102 		flags &= ~M_WAITOK;
4103 		flags |= M_NOWAIT;
4104 	}
4105 out:
4106 	return i;
4107 }
4108 
4109 static int
4110 zone_alloc_limit_hard(uma_zone_t zone, int count, int flags)
4111 {
4112 	uint64_t old, new, total, max;
4113 
4114 	/*
4115 	 * The hard case.  We're going to sleep because there were existing
4116 	 * sleepers or because we ran out of items.  This routine enforces
4117 	 * fairness by keeping fifo order.
4118 	 *
4119 	 * First release our ill gotten gains and make some noise.
4120 	 */
4121 	for (;;) {
4122 		zone_free_limit(zone, count);
4123 		zone_log_warning(zone);
4124 		zone_maxaction(zone);
4125 		if (flags & M_NOWAIT)
4126 			return (0);
4127 
4128 		/*
4129 		 * We need to allocate an item or set ourself as a sleeper
4130 		 * while the sleepq lock is held to avoid wakeup races.  This
4131 		 * is essentially a home rolled semaphore.
4132 		 */
4133 		sleepq_lock(&zone->uz_max_items);
4134 		old = zone->uz_items;
4135 		do {
4136 			MPASS(UZ_ITEMS_SLEEPERS(old) < UZ_ITEMS_SLEEPERS_MAX);
4137 			/* Cache the max since we will evaluate twice. */
4138 			max = zone->uz_max_items;
4139 			if (UZ_ITEMS_SLEEPERS(old) != 0 ||
4140 			    UZ_ITEMS_COUNT(old) >= max)
4141 				new = old + UZ_ITEMS_SLEEPER;
4142 			else
4143 				new = old + MIN(count, max - old);
4144 		} while (atomic_fcmpset_64(&zone->uz_items, &old, new) == 0);
4145 
4146 		/* We may have successfully allocated under the sleepq lock. */
4147 		if (UZ_ITEMS_SLEEPERS(new) == 0) {
4148 			sleepq_release(&zone->uz_max_items);
4149 			return (new - old);
4150 		}
4151 
4152 		/*
4153 		 * This is in a different cacheline from uz_items so that we
4154 		 * don't constantly invalidate the fastpath cacheline when we
4155 		 * adjust item counts.  This could be limited to toggling on
4156 		 * transitions.
4157 		 */
4158 		atomic_add_32(&zone->uz_sleepers, 1);
4159 		atomic_add_64(&zone->uz_sleeps, 1);
4160 
4161 		/*
4162 		 * We have added ourselves as a sleeper.  The sleepq lock
4163 		 * protects us from wakeup races.  Sleep now and then retry.
4164 		 */
4165 		sleepq_add(&zone->uz_max_items, NULL, "zonelimit", 0, 0);
4166 		sleepq_wait(&zone->uz_max_items, PVM);
4167 
4168 		/*
4169 		 * After wakeup, remove ourselves as a sleeper and try
4170 		 * again.  We no longer have the sleepq lock for protection.
4171 		 *
4172 		 * Subract ourselves as a sleeper while attempting to add
4173 		 * our count.
4174 		 */
4175 		atomic_subtract_32(&zone->uz_sleepers, 1);
4176 		old = atomic_fetchadd_64(&zone->uz_items,
4177 		    -(UZ_ITEMS_SLEEPER - count));
4178 		/* We're no longer a sleeper. */
4179 		old -= UZ_ITEMS_SLEEPER;
4180 
4181 		/*
4182 		 * If we're still at the limit, restart.  Notably do not
4183 		 * block on other sleepers.  Cache the max value to protect
4184 		 * against changes via sysctl.
4185 		 */
4186 		total = UZ_ITEMS_COUNT(old);
4187 		max = zone->uz_max_items;
4188 		if (total >= max)
4189 			continue;
4190 		/* Truncate if necessary, otherwise wake other sleepers. */
4191 		if (total + count > max) {
4192 			zone_free_limit(zone, total + count - max);
4193 			count = max - total;
4194 		} else if (total + count < max && UZ_ITEMS_SLEEPERS(old) != 0)
4195 			wakeup_one(&zone->uz_max_items);
4196 
4197 		return (count);
4198 	}
4199 }
4200 
4201 /*
4202  * Allocate 'count' items from our max_items limit.  Returns the number
4203  * available.  If M_NOWAIT is not specified it will sleep until at least
4204  * one item can be allocated.
4205  */
4206 static int
4207 zone_alloc_limit(uma_zone_t zone, int count, int flags)
4208 {
4209 	uint64_t old;
4210 	uint64_t max;
4211 
4212 	max = zone->uz_max_items;
4213 	MPASS(max > 0);
4214 
4215 	/*
4216 	 * We expect normal allocations to succeed with a simple
4217 	 * fetchadd.
4218 	 */
4219 	old = atomic_fetchadd_64(&zone->uz_items, count);
4220 	if (__predict_true(old + count <= max))
4221 		return (count);
4222 
4223 	/*
4224 	 * If we had some items and no sleepers just return the
4225 	 * truncated value.  We have to release the excess space
4226 	 * though because that may wake sleepers who weren't woken
4227 	 * because we were temporarily over the limit.
4228 	 */
4229 	if (old < max) {
4230 		zone_free_limit(zone, (old + count) - max);
4231 		return (max - old);
4232 	}
4233 	return (zone_alloc_limit_hard(zone, count, flags));
4234 }
4235 
4236 /*
4237  * Free a number of items back to the limit.
4238  */
4239 static void
4240 zone_free_limit(uma_zone_t zone, int count)
4241 {
4242 	uint64_t old;
4243 
4244 	MPASS(count > 0);
4245 
4246 	/*
4247 	 * In the common case we either have no sleepers or
4248 	 * are still over the limit and can just return.
4249 	 */
4250 	old = atomic_fetchadd_64(&zone->uz_items, -count);
4251 	if (__predict_true(UZ_ITEMS_SLEEPERS(old) == 0 ||
4252 	   UZ_ITEMS_COUNT(old) - count >= zone->uz_max_items))
4253 		return;
4254 
4255 	/*
4256 	 * Moderate the rate of wakeups.  Sleepers will continue
4257 	 * to generate wakeups if necessary.
4258 	 */
4259 	wakeup_one(&zone->uz_max_items);
4260 }
4261 
4262 static uma_bucket_t
4263 zone_alloc_bucket(uma_zone_t zone, void *udata, int domain, int flags)
4264 {
4265 	uma_bucket_t bucket;
4266 	int error, maxbucket, cnt;
4267 
4268 	CTR3(KTR_UMA, "zone_alloc_bucket zone %s(%p) domain %d", zone->uz_name,
4269 	    zone, domain);
4270 
4271 	/* Avoid allocs targeting empty domains. */
4272 	if (domain != UMA_ANYDOMAIN && VM_DOMAIN_EMPTY(domain))
4273 		domain = UMA_ANYDOMAIN;
4274 	else if ((zone->uz_flags & UMA_ZONE_ROUNDROBIN) != 0)
4275 		domain = UMA_ANYDOMAIN;
4276 
4277 	if (zone->uz_max_items > 0)
4278 		maxbucket = zone_alloc_limit(zone, zone->uz_bucket_size,
4279 		    M_NOWAIT);
4280 	else
4281 		maxbucket = zone->uz_bucket_size;
4282 	if (maxbucket == 0)
4283 		return (NULL);
4284 
4285 	/* Don't wait for buckets, preserve caller's NOVM setting. */
4286 	bucket = bucket_alloc(zone, udata, M_NOWAIT | (flags & M_NOVM));
4287 	if (bucket == NULL) {
4288 		cnt = 0;
4289 		goto out;
4290 	}
4291 
4292 	bucket->ub_cnt = zone->uz_import(zone->uz_arg, bucket->ub_bucket,
4293 	    MIN(maxbucket, bucket->ub_entries), domain, flags);
4294 
4295 	/*
4296 	 * Initialize the memory if necessary.
4297 	 */
4298 	if (bucket->ub_cnt != 0 && zone->uz_init != NULL) {
4299 		int i;
4300 
4301 		for (i = 0; i < bucket->ub_cnt; i++) {
4302 			kasan_mark_item_valid(zone, bucket->ub_bucket[i]);
4303 			error = zone->uz_init(bucket->ub_bucket[i],
4304 			    zone->uz_size, flags);
4305 			kasan_mark_item_invalid(zone, bucket->ub_bucket[i]);
4306 			if (error != 0)
4307 				break;
4308 		}
4309 
4310 		/*
4311 		 * If we couldn't initialize the whole bucket, put the
4312 		 * rest back onto the freelist.
4313 		 */
4314 		if (i != bucket->ub_cnt) {
4315 			zone->uz_release(zone->uz_arg, &bucket->ub_bucket[i],
4316 			    bucket->ub_cnt - i);
4317 #ifdef INVARIANTS
4318 			bzero(&bucket->ub_bucket[i],
4319 			    sizeof(void *) * (bucket->ub_cnt - i));
4320 #endif
4321 			bucket->ub_cnt = i;
4322 		}
4323 	}
4324 
4325 	cnt = bucket->ub_cnt;
4326 	if (bucket->ub_cnt == 0) {
4327 		bucket_free(zone, bucket, udata);
4328 		counter_u64_add(zone->uz_fails, 1);
4329 		bucket = NULL;
4330 	}
4331 out:
4332 	if (zone->uz_max_items > 0 && cnt < maxbucket)
4333 		zone_free_limit(zone, maxbucket - cnt);
4334 
4335 	return (bucket);
4336 }
4337 
4338 /*
4339  * Allocates a single item from a zone.
4340  *
4341  * Arguments
4342  *	zone   The zone to alloc for.
4343  *	udata  The data to be passed to the constructor.
4344  *	domain The domain to allocate from or UMA_ANYDOMAIN.
4345  *	flags  M_WAITOK, M_NOWAIT, M_ZERO.
4346  *
4347  * Returns
4348  *	NULL if there is no memory and M_NOWAIT is set
4349  *	An item if successful
4350  */
4351 
4352 static void *
4353 zone_alloc_item(uma_zone_t zone, void *udata, int domain, int flags)
4354 {
4355 	void *item;
4356 
4357 	if (zone->uz_max_items > 0 && zone_alloc_limit(zone, 1, flags) == 0) {
4358 		counter_u64_add(zone->uz_fails, 1);
4359 		return (NULL);
4360 	}
4361 
4362 	/* Avoid allocs targeting empty domains. */
4363 	if (domain != UMA_ANYDOMAIN && VM_DOMAIN_EMPTY(domain))
4364 		domain = UMA_ANYDOMAIN;
4365 
4366 	if (zone->uz_import(zone->uz_arg, &item, 1, domain, flags) != 1)
4367 		goto fail_cnt;
4368 
4369 	/*
4370 	 * We have to call both the zone's init (not the keg's init)
4371 	 * and the zone's ctor.  This is because the item is going from
4372 	 * a keg slab directly to the user, and the user is expecting it
4373 	 * to be both zone-init'd as well as zone-ctor'd.
4374 	 */
4375 	if (zone->uz_init != NULL) {
4376 		int error;
4377 
4378 		kasan_mark_item_valid(zone, item);
4379 		error = zone->uz_init(item, zone->uz_size, flags);
4380 		kasan_mark_item_invalid(zone, item);
4381 		if (error != 0) {
4382 			zone_free_item(zone, item, udata, SKIP_FINI | SKIP_CNT);
4383 			goto fail_cnt;
4384 		}
4385 	}
4386 	item = item_ctor(zone, zone->uz_flags, zone->uz_size, udata, flags,
4387 	    item);
4388 	if (item == NULL)
4389 		goto fail;
4390 
4391 	counter_u64_add(zone->uz_allocs, 1);
4392 	CTR3(KTR_UMA, "zone_alloc_item item %p from %s(%p)", item,
4393 	    zone->uz_name, zone);
4394 
4395 	return (item);
4396 
4397 fail_cnt:
4398 	counter_u64_add(zone->uz_fails, 1);
4399 fail:
4400 	if (zone->uz_max_items > 0)
4401 		zone_free_limit(zone, 1);
4402 	CTR2(KTR_UMA, "zone_alloc_item failed from %s(%p)",
4403 	    zone->uz_name, zone);
4404 
4405 	return (NULL);
4406 }
4407 
4408 /* See uma.h */
4409 void
4410 uma_zfree_smr(uma_zone_t zone, void *item)
4411 {
4412 	uma_cache_t cache;
4413 	uma_cache_bucket_t bucket;
4414 	int itemdomain;
4415 #ifdef NUMA
4416 	int uz_flags;
4417 #endif
4418 
4419 	CTR3(KTR_UMA, "uma_zfree_smr zone %s(%p) item %p",
4420 	    zone->uz_name, zone, item);
4421 
4422 #ifdef UMA_ZALLOC_DEBUG
4423 	KASSERT((zone->uz_flags & UMA_ZONE_SMR) != 0,
4424 	    ("uma_zfree_smr: called with non-SMR zone."));
4425 	KASSERT(item != NULL, ("uma_zfree_smr: Called with NULL pointer."));
4426 	SMR_ASSERT_NOT_ENTERED(zone->uz_smr);
4427 	if (uma_zfree_debug(zone, item, NULL) == EJUSTRETURN)
4428 		return;
4429 #endif
4430 	cache = &zone->uz_cpu[curcpu];
4431 	itemdomain = 0;
4432 #ifdef NUMA
4433 	uz_flags = cache_uz_flags(cache);
4434 	if ((uz_flags & UMA_ZONE_FIRSTTOUCH) != 0)
4435 		itemdomain = item_domain(item);
4436 #endif
4437 	critical_enter();
4438 	do {
4439 		cache = &zone->uz_cpu[curcpu];
4440 		/* SMR Zones must free to the free bucket. */
4441 		bucket = &cache->uc_freebucket;
4442 #ifdef NUMA
4443 		if ((uz_flags & UMA_ZONE_FIRSTTOUCH) != 0 &&
4444 		    PCPU_GET(domain) != itemdomain) {
4445 			bucket = &cache->uc_crossbucket;
4446 		}
4447 #endif
4448 		if (__predict_true(bucket->ucb_cnt < bucket->ucb_entries)) {
4449 			cache_bucket_push(cache, bucket, item);
4450 			critical_exit();
4451 			return;
4452 		}
4453 	} while (cache_free(zone, cache, NULL, itemdomain));
4454 	critical_exit();
4455 
4456 	/*
4457 	 * If nothing else caught this, we'll just do an internal free.
4458 	 */
4459 	zone_free_item(zone, item, NULL, SKIP_NONE);
4460 }
4461 
4462 /* See uma.h */
4463 void
4464 uma_zfree_arg(uma_zone_t zone, void *item, void *udata)
4465 {
4466 	uma_cache_t cache;
4467 	uma_cache_bucket_t bucket;
4468 	int itemdomain, uz_flags;
4469 
4470 	/* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
4471 	random_harvest_fast_uma(&zone, sizeof(zone), RANDOM_UMA);
4472 
4473 	CTR3(KTR_UMA, "uma_zfree_arg zone %s(%p) item %p",
4474 	    zone->uz_name, zone, item);
4475 
4476 #ifdef UMA_ZALLOC_DEBUG
4477 	KASSERT((zone->uz_flags & UMA_ZONE_SMR) == 0,
4478 	    ("uma_zfree_arg: called with SMR zone."));
4479 	if (uma_zfree_debug(zone, item, udata) == EJUSTRETURN)
4480 		return;
4481 #endif
4482         /* uma_zfree(..., NULL) does nothing, to match free(9). */
4483         if (item == NULL)
4484                 return;
4485 
4486 	/*
4487 	 * We are accessing the per-cpu cache without a critical section to
4488 	 * fetch size and flags.  This is acceptable, if we are preempted we
4489 	 * will simply read another cpu's line.
4490 	 */
4491 	cache = &zone->uz_cpu[curcpu];
4492 	uz_flags = cache_uz_flags(cache);
4493 	if (UMA_ALWAYS_CTORDTOR ||
4494 	    __predict_false((uz_flags & UMA_ZFLAG_CTORDTOR) != 0))
4495 		item_dtor(zone, item, cache_uz_size(cache), udata, SKIP_NONE);
4496 
4497 	/*
4498 	 * The race here is acceptable.  If we miss it we'll just have to wait
4499 	 * a little longer for the limits to be reset.
4500 	 */
4501 	if (__predict_false(uz_flags & UMA_ZFLAG_LIMIT)) {
4502 		if (atomic_load_32(&zone->uz_sleepers) > 0)
4503 			goto zfree_item;
4504 	}
4505 
4506 	/*
4507 	 * If possible, free to the per-CPU cache.  There are two
4508 	 * requirements for safe access to the per-CPU cache: (1) the thread
4509 	 * accessing the cache must not be preempted or yield during access,
4510 	 * and (2) the thread must not migrate CPUs without switching which
4511 	 * cache it accesses.  We rely on a critical section to prevent
4512 	 * preemption and migration.  We release the critical section in
4513 	 * order to acquire the zone mutex if we are unable to free to the
4514 	 * current cache; when we re-acquire the critical section, we must
4515 	 * detect and handle migration if it has occurred.
4516 	 */
4517 	itemdomain = 0;
4518 #ifdef NUMA
4519 	if ((uz_flags & UMA_ZONE_FIRSTTOUCH) != 0)
4520 		itemdomain = item_domain(item);
4521 #endif
4522 	critical_enter();
4523 	do {
4524 		cache = &zone->uz_cpu[curcpu];
4525 		/*
4526 		 * Try to free into the allocbucket first to give LIFO
4527 		 * ordering for cache-hot datastructures.  Spill over
4528 		 * into the freebucket if necessary.  Alloc will swap
4529 		 * them if one runs dry.
4530 		 */
4531 		bucket = &cache->uc_allocbucket;
4532 #ifdef NUMA
4533 		if ((uz_flags & UMA_ZONE_FIRSTTOUCH) != 0 &&
4534 		    PCPU_GET(domain) != itemdomain) {
4535 			bucket = &cache->uc_crossbucket;
4536 		} else
4537 #endif
4538 		if (bucket->ucb_cnt == bucket->ucb_entries &&
4539 		   cache->uc_freebucket.ucb_cnt <
4540 		   cache->uc_freebucket.ucb_entries)
4541 			cache_bucket_swap(&cache->uc_freebucket,
4542 			    &cache->uc_allocbucket);
4543 		if (__predict_true(bucket->ucb_cnt < bucket->ucb_entries)) {
4544 			cache_bucket_push(cache, bucket, item);
4545 			critical_exit();
4546 			return;
4547 		}
4548 	} while (cache_free(zone, cache, udata, itemdomain));
4549 	critical_exit();
4550 
4551 	/*
4552 	 * If nothing else caught this, we'll just do an internal free.
4553 	 */
4554 zfree_item:
4555 	zone_free_item(zone, item, udata, SKIP_DTOR);
4556 }
4557 
4558 #ifdef NUMA
4559 /*
4560  * sort crossdomain free buckets to domain correct buckets and cache
4561  * them.
4562  */
4563 static void
4564 zone_free_cross(uma_zone_t zone, uma_bucket_t bucket, void *udata)
4565 {
4566 	struct uma_bucketlist emptybuckets, fullbuckets;
4567 	uma_zone_domain_t zdom;
4568 	uma_bucket_t b;
4569 	smr_seq_t seq;
4570 	void *item;
4571 	int domain;
4572 
4573 	CTR3(KTR_UMA,
4574 	    "uma_zfree: zone %s(%p) draining cross bucket %p",
4575 	    zone->uz_name, zone, bucket);
4576 
4577 	/*
4578 	 * It is possible for buckets to arrive here out of order so we fetch
4579 	 * the current smr seq rather than accepting the bucket's.
4580 	 */
4581 	seq = SMR_SEQ_INVALID;
4582 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0)
4583 		seq = smr_advance(zone->uz_smr);
4584 
4585 	/*
4586 	 * To avoid having ndomain * ndomain buckets for sorting we have a
4587 	 * lock on the current crossfree bucket.  A full matrix with
4588 	 * per-domain locking could be used if necessary.
4589 	 */
4590 	STAILQ_INIT(&emptybuckets);
4591 	STAILQ_INIT(&fullbuckets);
4592 	ZONE_CROSS_LOCK(zone);
4593 	for (; bucket->ub_cnt > 0; bucket->ub_cnt--) {
4594 		item = bucket->ub_bucket[bucket->ub_cnt - 1];
4595 		domain = item_domain(item);
4596 		zdom = ZDOM_GET(zone, domain);
4597 		if (zdom->uzd_cross == NULL) {
4598 			if ((b = STAILQ_FIRST(&emptybuckets)) != NULL) {
4599 				STAILQ_REMOVE_HEAD(&emptybuckets, ub_link);
4600 				zdom->uzd_cross = b;
4601 			} else {
4602 				/*
4603 				 * Avoid allocating a bucket with the cross lock
4604 				 * held, since allocation can trigger a
4605 				 * cross-domain free and bucket zones may
4606 				 * allocate from each other.
4607 				 */
4608 				ZONE_CROSS_UNLOCK(zone);
4609 				b = bucket_alloc(zone, udata, M_NOWAIT);
4610 				if (b == NULL)
4611 					goto out;
4612 				ZONE_CROSS_LOCK(zone);
4613 				if (zdom->uzd_cross != NULL) {
4614 					STAILQ_INSERT_HEAD(&emptybuckets, b,
4615 					    ub_link);
4616 				} else {
4617 					zdom->uzd_cross = b;
4618 				}
4619 			}
4620 		}
4621 		b = zdom->uzd_cross;
4622 		b->ub_bucket[b->ub_cnt++] = item;
4623 		b->ub_seq = seq;
4624 		if (b->ub_cnt == b->ub_entries) {
4625 			STAILQ_INSERT_HEAD(&fullbuckets, b, ub_link);
4626 			if ((b = STAILQ_FIRST(&emptybuckets)) != NULL)
4627 				STAILQ_REMOVE_HEAD(&emptybuckets, ub_link);
4628 			zdom->uzd_cross = b;
4629 		}
4630 	}
4631 	ZONE_CROSS_UNLOCK(zone);
4632 out:
4633 	if (bucket->ub_cnt == 0)
4634 		bucket->ub_seq = SMR_SEQ_INVALID;
4635 	bucket_free(zone, bucket, udata);
4636 
4637 	while ((b = STAILQ_FIRST(&emptybuckets)) != NULL) {
4638 		STAILQ_REMOVE_HEAD(&emptybuckets, ub_link);
4639 		bucket_free(zone, b, udata);
4640 	}
4641 	while ((b = STAILQ_FIRST(&fullbuckets)) != NULL) {
4642 		STAILQ_REMOVE_HEAD(&fullbuckets, ub_link);
4643 		domain = item_domain(b->ub_bucket[0]);
4644 		zone_put_bucket(zone, domain, b, udata, true);
4645 	}
4646 }
4647 #endif
4648 
4649 static void
4650 zone_free_bucket(uma_zone_t zone, uma_bucket_t bucket, void *udata,
4651     int itemdomain, bool ws)
4652 {
4653 
4654 #ifdef NUMA
4655 	/*
4656 	 * Buckets coming from the wrong domain will be entirely for the
4657 	 * only other domain on two domain systems.  In this case we can
4658 	 * simply cache them.  Otherwise we need to sort them back to
4659 	 * correct domains.
4660 	 */
4661 	if ((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) != 0 &&
4662 	    vm_ndomains > 2 && PCPU_GET(domain) != itemdomain) {
4663 		zone_free_cross(zone, bucket, udata);
4664 		return;
4665 	}
4666 #endif
4667 
4668 	/*
4669 	 * Attempt to save the bucket in the zone's domain bucket cache.
4670 	 */
4671 	CTR3(KTR_UMA,
4672 	    "uma_zfree: zone %s(%p) putting bucket %p on free list",
4673 	    zone->uz_name, zone, bucket);
4674 	/* ub_cnt is pointing to the last free item */
4675 	if ((zone->uz_flags & UMA_ZONE_ROUNDROBIN) != 0)
4676 		itemdomain = zone_domain_lowest(zone, itemdomain);
4677 	zone_put_bucket(zone, itemdomain, bucket, udata, ws);
4678 }
4679 
4680 /*
4681  * Populate a free or cross bucket for the current cpu cache.  Free any
4682  * existing full bucket either to the zone cache or back to the slab layer.
4683  *
4684  * Enters and returns in a critical section.  false return indicates that
4685  * we can not satisfy this free in the cache layer.  true indicates that
4686  * the caller should retry.
4687  */
4688 static __noinline bool
4689 cache_free(uma_zone_t zone, uma_cache_t cache, void *udata, int itemdomain)
4690 {
4691 	uma_cache_bucket_t cbucket;
4692 	uma_bucket_t newbucket, bucket;
4693 
4694 	CRITICAL_ASSERT(curthread);
4695 
4696 	if (zone->uz_bucket_size == 0)
4697 		return false;
4698 
4699 	cache = &zone->uz_cpu[curcpu];
4700 	newbucket = NULL;
4701 
4702 	/*
4703 	 * FIRSTTOUCH domains need to free to the correct zdom.  When
4704 	 * enabled this is the zdom of the item.   The bucket is the
4705 	 * cross bucket if the current domain and itemdomain do not match.
4706 	 */
4707 	cbucket = &cache->uc_freebucket;
4708 #ifdef NUMA
4709 	if ((cache_uz_flags(cache) & UMA_ZONE_FIRSTTOUCH) != 0) {
4710 		if (PCPU_GET(domain) != itemdomain) {
4711 			cbucket = &cache->uc_crossbucket;
4712 			if (cbucket->ucb_cnt != 0)
4713 				counter_u64_add(zone->uz_xdomain,
4714 				    cbucket->ucb_cnt);
4715 		}
4716 	}
4717 #endif
4718 	bucket = cache_bucket_unload(cbucket);
4719 	KASSERT(bucket == NULL || bucket->ub_cnt == bucket->ub_entries,
4720 	    ("cache_free: Entered with non-full free bucket."));
4721 
4722 	/* We are no longer associated with this CPU. */
4723 	critical_exit();
4724 
4725 	/*
4726 	 * Don't let SMR zones operate without a free bucket.  Force
4727 	 * a synchronize and re-use this one.  We will only degrade
4728 	 * to a synchronize every bucket_size items rather than every
4729 	 * item if we fail to allocate a bucket.
4730 	 */
4731 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0) {
4732 		if (bucket != NULL)
4733 			bucket->ub_seq = smr_advance(zone->uz_smr);
4734 		newbucket = bucket_alloc(zone, udata, M_NOWAIT);
4735 		if (newbucket == NULL && bucket != NULL) {
4736 			bucket_drain(zone, bucket);
4737 			newbucket = bucket;
4738 			bucket = NULL;
4739 		}
4740 	} else if (!bucketdisable)
4741 		newbucket = bucket_alloc(zone, udata, M_NOWAIT);
4742 
4743 	if (bucket != NULL)
4744 		zone_free_bucket(zone, bucket, udata, itemdomain, true);
4745 
4746 	critical_enter();
4747 	if ((bucket = newbucket) == NULL)
4748 		return (false);
4749 	cache = &zone->uz_cpu[curcpu];
4750 #ifdef NUMA
4751 	/*
4752 	 * Check to see if we should be populating the cross bucket.  If it
4753 	 * is already populated we will fall through and attempt to populate
4754 	 * the free bucket.
4755 	 */
4756 	if ((cache_uz_flags(cache) & UMA_ZONE_FIRSTTOUCH) != 0) {
4757 		if (PCPU_GET(domain) != itemdomain &&
4758 		    cache->uc_crossbucket.ucb_bucket == NULL) {
4759 			cache_bucket_load_cross(cache, bucket);
4760 			return (true);
4761 		}
4762 	}
4763 #endif
4764 	/*
4765 	 * We may have lost the race to fill the bucket or switched CPUs.
4766 	 */
4767 	if (cache->uc_freebucket.ucb_bucket != NULL) {
4768 		critical_exit();
4769 		bucket_free(zone, bucket, udata);
4770 		critical_enter();
4771 	} else
4772 		cache_bucket_load_free(cache, bucket);
4773 
4774 	return (true);
4775 }
4776 
4777 static void
4778 slab_free_item(uma_zone_t zone, uma_slab_t slab, void *item)
4779 {
4780 	uma_keg_t keg;
4781 	uma_domain_t dom;
4782 	int freei;
4783 
4784 	keg = zone->uz_keg;
4785 	KEG_LOCK_ASSERT(keg, slab->us_domain);
4786 
4787 	/* Do we need to remove from any lists? */
4788 	dom = &keg->uk_domain[slab->us_domain];
4789 	if (slab->us_freecount + 1 == keg->uk_ipers) {
4790 		LIST_REMOVE(slab, us_link);
4791 		LIST_INSERT_HEAD(&dom->ud_free_slab, slab, us_link);
4792 		dom->ud_free_slabs++;
4793 	} else if (slab->us_freecount == 0) {
4794 		LIST_REMOVE(slab, us_link);
4795 		LIST_INSERT_HEAD(&dom->ud_part_slab, slab, us_link);
4796 	}
4797 
4798 	/* Slab management. */
4799 	freei = slab_item_index(slab, keg, item);
4800 	BIT_SET(keg->uk_ipers, freei, &slab->us_free);
4801 	slab->us_freecount++;
4802 
4803 	/* Keg statistics. */
4804 	dom->ud_free_items++;
4805 }
4806 
4807 static void
4808 zone_release(void *arg, void **bucket, int cnt)
4809 {
4810 	struct mtx *lock;
4811 	uma_zone_t zone;
4812 	uma_slab_t slab;
4813 	uma_keg_t keg;
4814 	uint8_t *mem;
4815 	void *item;
4816 	int i;
4817 
4818 	zone = arg;
4819 	keg = zone->uz_keg;
4820 	lock = NULL;
4821 	if (__predict_false((zone->uz_flags & UMA_ZFLAG_HASH) != 0))
4822 		lock = KEG_LOCK(keg, 0);
4823 	for (i = 0; i < cnt; i++) {
4824 		item = bucket[i];
4825 		if (__predict_true((zone->uz_flags & UMA_ZFLAG_VTOSLAB) != 0)) {
4826 			slab = vtoslab((vm_offset_t)item);
4827 		} else {
4828 			mem = (uint8_t *)((uintptr_t)item & (~UMA_SLAB_MASK));
4829 			if ((zone->uz_flags & UMA_ZFLAG_HASH) != 0)
4830 				slab = hash_sfind(&keg->uk_hash, mem);
4831 			else
4832 				slab = (uma_slab_t)(mem + keg->uk_pgoff);
4833 		}
4834 		if (lock != KEG_LOCKPTR(keg, slab->us_domain)) {
4835 			if (lock != NULL)
4836 				mtx_unlock(lock);
4837 			lock = KEG_LOCK(keg, slab->us_domain);
4838 		}
4839 		slab_free_item(zone, slab, item);
4840 	}
4841 	if (lock != NULL)
4842 		mtx_unlock(lock);
4843 }
4844 
4845 /*
4846  * Frees a single item to any zone.
4847  *
4848  * Arguments:
4849  *	zone   The zone to free to
4850  *	item   The item we're freeing
4851  *	udata  User supplied data for the dtor
4852  *	skip   Skip dtors and finis
4853  */
4854 static __noinline void
4855 zone_free_item(uma_zone_t zone, void *item, void *udata, enum zfreeskip skip)
4856 {
4857 
4858 	/*
4859 	 * If a free is sent directly to an SMR zone we have to
4860 	 * synchronize immediately because the item can instantly
4861 	 * be reallocated. This should only happen in degenerate
4862 	 * cases when no memory is available for per-cpu caches.
4863 	 */
4864 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0 && skip == SKIP_NONE)
4865 		smr_synchronize(zone->uz_smr);
4866 
4867 	item_dtor(zone, item, zone->uz_size, udata, skip);
4868 
4869 	if (skip < SKIP_FINI && zone->uz_fini) {
4870 		kasan_mark_item_valid(zone, item);
4871 		zone->uz_fini(item, zone->uz_size);
4872 		kasan_mark_item_invalid(zone, item);
4873 	}
4874 
4875 	zone->uz_release(zone->uz_arg, &item, 1);
4876 
4877 	if (skip & SKIP_CNT)
4878 		return;
4879 
4880 	counter_u64_add(zone->uz_frees, 1);
4881 
4882 	if (zone->uz_max_items > 0)
4883 		zone_free_limit(zone, 1);
4884 }
4885 
4886 /* See uma.h */
4887 int
4888 uma_zone_set_max(uma_zone_t zone, int nitems)
4889 {
4890 
4891 	/*
4892 	 * If the limit is small, we may need to constrain the maximum per-CPU
4893 	 * cache size, or disable caching entirely.
4894 	 */
4895 	uma_zone_set_maxcache(zone, nitems);
4896 
4897 	/*
4898 	 * XXX This can misbehave if the zone has any allocations with
4899 	 * no limit and a limit is imposed.  There is currently no
4900 	 * way to clear a limit.
4901 	 */
4902 	ZONE_LOCK(zone);
4903 	if (zone->uz_max_items == 0)
4904 		ZONE_ASSERT_COLD(zone);
4905 	zone->uz_max_items = nitems;
4906 	zone->uz_flags |= UMA_ZFLAG_LIMIT;
4907 	zone_update_caches(zone);
4908 	/* We may need to wake waiters. */
4909 	wakeup(&zone->uz_max_items);
4910 	ZONE_UNLOCK(zone);
4911 
4912 	return (nitems);
4913 }
4914 
4915 /* See uma.h */
4916 void
4917 uma_zone_set_maxcache(uma_zone_t zone, int nitems)
4918 {
4919 	int bpcpu, bpdom, bsize, nb;
4920 
4921 	ZONE_LOCK(zone);
4922 
4923 	/*
4924 	 * Compute a lower bound on the number of items that may be cached in
4925 	 * the zone.  Each CPU gets at least two buckets, and for cross-domain
4926 	 * frees we use an additional bucket per CPU and per domain.  Select the
4927 	 * largest bucket size that does not exceed half of the requested limit,
4928 	 * with the left over space given to the full bucket cache.
4929 	 */
4930 	bpdom = 0;
4931 	bpcpu = 2;
4932 #ifdef NUMA
4933 	if ((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) != 0 && vm_ndomains > 1) {
4934 		bpcpu++;
4935 		bpdom++;
4936 	}
4937 #endif
4938 	nb = bpcpu * mp_ncpus + bpdom * vm_ndomains;
4939 	bsize = nitems / nb / 2;
4940 	if (bsize > BUCKET_MAX)
4941 		bsize = BUCKET_MAX;
4942 	else if (bsize == 0 && nitems / nb > 0)
4943 		bsize = 1;
4944 	zone->uz_bucket_size_max = zone->uz_bucket_size = bsize;
4945 	if (zone->uz_bucket_size_min > zone->uz_bucket_size_max)
4946 		zone->uz_bucket_size_min = zone->uz_bucket_size_max;
4947 	zone->uz_bucket_max = nitems - nb * bsize;
4948 	ZONE_UNLOCK(zone);
4949 }
4950 
4951 /* See uma.h */
4952 int
4953 uma_zone_get_max(uma_zone_t zone)
4954 {
4955 	int nitems;
4956 
4957 	nitems = atomic_load_64(&zone->uz_max_items);
4958 
4959 	return (nitems);
4960 }
4961 
4962 /* See uma.h */
4963 void
4964 uma_zone_set_warning(uma_zone_t zone, const char *warning)
4965 {
4966 
4967 	ZONE_ASSERT_COLD(zone);
4968 	zone->uz_warning = warning;
4969 }
4970 
4971 /* See uma.h */
4972 void
4973 uma_zone_set_maxaction(uma_zone_t zone, uma_maxaction_t maxaction)
4974 {
4975 
4976 	ZONE_ASSERT_COLD(zone);
4977 	TASK_INIT(&zone->uz_maxaction, 0, (task_fn_t *)maxaction, zone);
4978 }
4979 
4980 /* See uma.h */
4981 int
4982 uma_zone_get_cur(uma_zone_t zone)
4983 {
4984 	int64_t nitems;
4985 	u_int i;
4986 
4987 	nitems = 0;
4988 	if (zone->uz_allocs != EARLY_COUNTER && zone->uz_frees != EARLY_COUNTER)
4989 		nitems = counter_u64_fetch(zone->uz_allocs) -
4990 		    counter_u64_fetch(zone->uz_frees);
4991 	CPU_FOREACH(i)
4992 		nitems += atomic_load_64(&zone->uz_cpu[i].uc_allocs) -
4993 		    atomic_load_64(&zone->uz_cpu[i].uc_frees);
4994 
4995 	return (nitems < 0 ? 0 : nitems);
4996 }
4997 
4998 static uint64_t
4999 uma_zone_get_allocs(uma_zone_t zone)
5000 {
5001 	uint64_t nitems;
5002 	u_int i;
5003 
5004 	nitems = 0;
5005 	if (zone->uz_allocs != EARLY_COUNTER)
5006 		nitems = counter_u64_fetch(zone->uz_allocs);
5007 	CPU_FOREACH(i)
5008 		nitems += atomic_load_64(&zone->uz_cpu[i].uc_allocs);
5009 
5010 	return (nitems);
5011 }
5012 
5013 static uint64_t
5014 uma_zone_get_frees(uma_zone_t zone)
5015 {
5016 	uint64_t nitems;
5017 	u_int i;
5018 
5019 	nitems = 0;
5020 	if (zone->uz_frees != EARLY_COUNTER)
5021 		nitems = counter_u64_fetch(zone->uz_frees);
5022 	CPU_FOREACH(i)
5023 		nitems += atomic_load_64(&zone->uz_cpu[i].uc_frees);
5024 
5025 	return (nitems);
5026 }
5027 
5028 #ifdef INVARIANTS
5029 /* Used only for KEG_ASSERT_COLD(). */
5030 static uint64_t
5031 uma_keg_get_allocs(uma_keg_t keg)
5032 {
5033 	uma_zone_t z;
5034 	uint64_t nitems;
5035 
5036 	nitems = 0;
5037 	LIST_FOREACH(z, &keg->uk_zones, uz_link)
5038 		nitems += uma_zone_get_allocs(z);
5039 
5040 	return (nitems);
5041 }
5042 #endif
5043 
5044 /* See uma.h */
5045 void
5046 uma_zone_set_init(uma_zone_t zone, uma_init uminit)
5047 {
5048 	uma_keg_t keg;
5049 
5050 	KEG_GET(zone, keg);
5051 	KEG_ASSERT_COLD(keg);
5052 	keg->uk_init = uminit;
5053 }
5054 
5055 /* See uma.h */
5056 void
5057 uma_zone_set_fini(uma_zone_t zone, uma_fini fini)
5058 {
5059 	uma_keg_t keg;
5060 
5061 	KEG_GET(zone, keg);
5062 	KEG_ASSERT_COLD(keg);
5063 	keg->uk_fini = fini;
5064 }
5065 
5066 /* See uma.h */
5067 void
5068 uma_zone_set_zinit(uma_zone_t zone, uma_init zinit)
5069 {
5070 
5071 	ZONE_ASSERT_COLD(zone);
5072 	zone->uz_init = zinit;
5073 }
5074 
5075 /* See uma.h */
5076 void
5077 uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini)
5078 {
5079 
5080 	ZONE_ASSERT_COLD(zone);
5081 	zone->uz_fini = zfini;
5082 }
5083 
5084 /* See uma.h */
5085 void
5086 uma_zone_set_freef(uma_zone_t zone, uma_free freef)
5087 {
5088 	uma_keg_t keg;
5089 
5090 	KEG_GET(zone, keg);
5091 	KEG_ASSERT_COLD(keg);
5092 	keg->uk_freef = freef;
5093 }
5094 
5095 /* See uma.h */
5096 void
5097 uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf)
5098 {
5099 	uma_keg_t keg;
5100 
5101 	KEG_GET(zone, keg);
5102 	KEG_ASSERT_COLD(keg);
5103 	keg->uk_allocf = allocf;
5104 }
5105 
5106 /* See uma.h */
5107 void
5108 uma_zone_set_smr(uma_zone_t zone, smr_t smr)
5109 {
5110 
5111 	ZONE_ASSERT_COLD(zone);
5112 
5113 	KASSERT(smr != NULL, ("Got NULL smr"));
5114 	KASSERT((zone->uz_flags & UMA_ZONE_SMR) == 0,
5115 	    ("zone %p (%s) already uses SMR", zone, zone->uz_name));
5116 	zone->uz_flags |= UMA_ZONE_SMR;
5117 	zone->uz_smr = smr;
5118 	zone_update_caches(zone);
5119 }
5120 
5121 smr_t
5122 uma_zone_get_smr(uma_zone_t zone)
5123 {
5124 
5125 	return (zone->uz_smr);
5126 }
5127 
5128 /* See uma.h */
5129 void
5130 uma_zone_reserve(uma_zone_t zone, int items)
5131 {
5132 	uma_keg_t keg;
5133 
5134 	KEG_GET(zone, keg);
5135 	KEG_ASSERT_COLD(keg);
5136 	keg->uk_reserve = items;
5137 }
5138 
5139 /* See uma.h */
5140 int
5141 uma_zone_reserve_kva(uma_zone_t zone, int count)
5142 {
5143 	uma_keg_t keg;
5144 	vm_offset_t kva;
5145 	u_int pages;
5146 
5147 	KEG_GET(zone, keg);
5148 	KEG_ASSERT_COLD(keg);
5149 	ZONE_ASSERT_COLD(zone);
5150 
5151 	pages = howmany(count, keg->uk_ipers) * keg->uk_ppera;
5152 
5153 #ifdef UMA_MD_SMALL_ALLOC
5154 	if (keg->uk_ppera > 1) {
5155 #else
5156 	if (1) {
5157 #endif
5158 		kva = kva_alloc((vm_size_t)pages * PAGE_SIZE);
5159 		if (kva == 0)
5160 			return (0);
5161 	} else
5162 		kva = 0;
5163 
5164 	MPASS(keg->uk_kva == 0);
5165 	keg->uk_kva = kva;
5166 	keg->uk_offset = 0;
5167 	zone->uz_max_items = pages * keg->uk_ipers;
5168 #ifdef UMA_MD_SMALL_ALLOC
5169 	keg->uk_allocf = (keg->uk_ppera > 1) ? noobj_alloc : uma_small_alloc;
5170 #else
5171 	keg->uk_allocf = noobj_alloc;
5172 #endif
5173 	keg->uk_flags |= UMA_ZFLAG_LIMIT | UMA_ZONE_NOFREE;
5174 	zone->uz_flags |= UMA_ZFLAG_LIMIT | UMA_ZONE_NOFREE;
5175 	zone_update_caches(zone);
5176 
5177 	return (1);
5178 }
5179 
5180 /* See uma.h */
5181 void
5182 uma_prealloc(uma_zone_t zone, int items)
5183 {
5184 	struct vm_domainset_iter di;
5185 	uma_domain_t dom;
5186 	uma_slab_t slab;
5187 	uma_keg_t keg;
5188 	int aflags, domain, slabs;
5189 
5190 	KEG_GET(zone, keg);
5191 	slabs = howmany(items, keg->uk_ipers);
5192 	while (slabs-- > 0) {
5193 		aflags = M_NOWAIT;
5194 		vm_domainset_iter_policy_ref_init(&di, &keg->uk_dr, &domain,
5195 		    &aflags);
5196 		for (;;) {
5197 			slab = keg_alloc_slab(keg, zone, domain, M_WAITOK,
5198 			    aflags);
5199 			if (slab != NULL) {
5200 				dom = &keg->uk_domain[slab->us_domain];
5201 				/*
5202 				 * keg_alloc_slab() always returns a slab on the
5203 				 * partial list.
5204 				 */
5205 				LIST_REMOVE(slab, us_link);
5206 				LIST_INSERT_HEAD(&dom->ud_free_slab, slab,
5207 				    us_link);
5208 				dom->ud_free_slabs++;
5209 				KEG_UNLOCK(keg, slab->us_domain);
5210 				break;
5211 			}
5212 			if (vm_domainset_iter_policy(&di, &domain) != 0)
5213 				vm_wait_doms(&keg->uk_dr.dr_policy->ds_mask, 0);
5214 		}
5215 	}
5216 }
5217 
5218 /*
5219  * Returns a snapshot of memory consumption in bytes.
5220  */
5221 size_t
5222 uma_zone_memory(uma_zone_t zone)
5223 {
5224 	size_t sz;
5225 	int i;
5226 
5227 	sz = 0;
5228 	if (zone->uz_flags & UMA_ZFLAG_CACHE) {
5229 		for (i = 0; i < vm_ndomains; i++)
5230 			sz += ZDOM_GET(zone, i)->uzd_nitems;
5231 		return (sz * zone->uz_size);
5232 	}
5233 	for (i = 0; i < vm_ndomains; i++)
5234 		sz += zone->uz_keg->uk_domain[i].ud_pages;
5235 
5236 	return (sz * PAGE_SIZE);
5237 }
5238 
5239 struct uma_reclaim_args {
5240 	int	domain;
5241 	int	req;
5242 };
5243 
5244 static void
5245 uma_reclaim_domain_cb(uma_zone_t zone, void *arg)
5246 {
5247 	struct uma_reclaim_args *args;
5248 
5249 	args = arg;
5250 	if ((zone->uz_flags & UMA_ZONE_UNMANAGED) == 0)
5251 		uma_zone_reclaim_domain(zone, args->req, args->domain);
5252 }
5253 
5254 /* See uma.h */
5255 void
5256 uma_reclaim(int req)
5257 {
5258 	uma_reclaim_domain(req, UMA_ANYDOMAIN);
5259 }
5260 
5261 void
5262 uma_reclaim_domain(int req, int domain)
5263 {
5264 	struct uma_reclaim_args args;
5265 
5266 	bucket_enable();
5267 
5268 	args.domain = domain;
5269 	args.req = req;
5270 
5271 	sx_slock(&uma_reclaim_lock);
5272 	switch (req) {
5273 	case UMA_RECLAIM_TRIM:
5274 	case UMA_RECLAIM_DRAIN:
5275 		zone_foreach(uma_reclaim_domain_cb, &args);
5276 		break;
5277 	case UMA_RECLAIM_DRAIN_CPU:
5278 		zone_foreach(uma_reclaim_domain_cb, &args);
5279 		pcpu_cache_drain_safe(NULL);
5280 		zone_foreach(uma_reclaim_domain_cb, &args);
5281 		break;
5282 	default:
5283 		panic("unhandled reclamation request %d", req);
5284 	}
5285 
5286 	/*
5287 	 * Some slabs may have been freed but this zone will be visited early
5288 	 * we visit again so that we can free pages that are empty once other
5289 	 * zones are drained.  We have to do the same for buckets.
5290 	 */
5291 	uma_zone_reclaim_domain(slabzones[0], UMA_RECLAIM_DRAIN, domain);
5292 	uma_zone_reclaim_domain(slabzones[1], UMA_RECLAIM_DRAIN, domain);
5293 	bucket_zone_drain(domain);
5294 	sx_sunlock(&uma_reclaim_lock);
5295 }
5296 
5297 static volatile int uma_reclaim_needed;
5298 
5299 void
5300 uma_reclaim_wakeup(void)
5301 {
5302 
5303 	if (atomic_fetchadd_int(&uma_reclaim_needed, 1) == 0)
5304 		wakeup(uma_reclaim);
5305 }
5306 
5307 void
5308 uma_reclaim_worker(void *arg __unused)
5309 {
5310 
5311 	for (;;) {
5312 		sx_xlock(&uma_reclaim_lock);
5313 		while (atomic_load_int(&uma_reclaim_needed) == 0)
5314 			sx_sleep(uma_reclaim, &uma_reclaim_lock, PVM, "umarcl",
5315 			    hz);
5316 		sx_xunlock(&uma_reclaim_lock);
5317 		EVENTHANDLER_INVOKE(vm_lowmem, VM_LOW_KMEM);
5318 		uma_reclaim(UMA_RECLAIM_DRAIN_CPU);
5319 		atomic_store_int(&uma_reclaim_needed, 0);
5320 		/* Don't fire more than once per-second. */
5321 		pause("umarclslp", hz);
5322 	}
5323 }
5324 
5325 /* See uma.h */
5326 void
5327 uma_zone_reclaim(uma_zone_t zone, int req)
5328 {
5329 	uma_zone_reclaim_domain(zone, req, UMA_ANYDOMAIN);
5330 }
5331 
5332 void
5333 uma_zone_reclaim_domain(uma_zone_t zone, int req, int domain)
5334 {
5335 	switch (req) {
5336 	case UMA_RECLAIM_TRIM:
5337 		zone_reclaim(zone, domain, M_NOWAIT, false);
5338 		break;
5339 	case UMA_RECLAIM_DRAIN:
5340 		zone_reclaim(zone, domain, M_NOWAIT, true);
5341 		break;
5342 	case UMA_RECLAIM_DRAIN_CPU:
5343 		pcpu_cache_drain_safe(zone);
5344 		zone_reclaim(zone, domain, M_NOWAIT, true);
5345 		break;
5346 	default:
5347 		panic("unhandled reclamation request %d", req);
5348 	}
5349 }
5350 
5351 /* See uma.h */
5352 int
5353 uma_zone_exhausted(uma_zone_t zone)
5354 {
5355 
5356 	return (atomic_load_32(&zone->uz_sleepers) > 0);
5357 }
5358 
5359 unsigned long
5360 uma_limit(void)
5361 {
5362 
5363 	return (uma_kmem_limit);
5364 }
5365 
5366 void
5367 uma_set_limit(unsigned long limit)
5368 {
5369 
5370 	uma_kmem_limit = limit;
5371 }
5372 
5373 unsigned long
5374 uma_size(void)
5375 {
5376 
5377 	return (atomic_load_long(&uma_kmem_total));
5378 }
5379 
5380 long
5381 uma_avail(void)
5382 {
5383 
5384 	return (uma_kmem_limit - uma_size());
5385 }
5386 
5387 #ifdef DDB
5388 /*
5389  * Generate statistics across both the zone and its per-cpu cache's.  Return
5390  * desired statistics if the pointer is non-NULL for that statistic.
5391  *
5392  * Note: does not update the zone statistics, as it can't safely clear the
5393  * per-CPU cache statistic.
5394  *
5395  */
5396 static void
5397 uma_zone_sumstat(uma_zone_t z, long *cachefreep, uint64_t *allocsp,
5398     uint64_t *freesp, uint64_t *sleepsp, uint64_t *xdomainp)
5399 {
5400 	uma_cache_t cache;
5401 	uint64_t allocs, frees, sleeps, xdomain;
5402 	int cachefree, cpu;
5403 
5404 	allocs = frees = sleeps = xdomain = 0;
5405 	cachefree = 0;
5406 	CPU_FOREACH(cpu) {
5407 		cache = &z->uz_cpu[cpu];
5408 		cachefree += cache->uc_allocbucket.ucb_cnt;
5409 		cachefree += cache->uc_freebucket.ucb_cnt;
5410 		xdomain += cache->uc_crossbucket.ucb_cnt;
5411 		cachefree += cache->uc_crossbucket.ucb_cnt;
5412 		allocs += cache->uc_allocs;
5413 		frees += cache->uc_frees;
5414 	}
5415 	allocs += counter_u64_fetch(z->uz_allocs);
5416 	frees += counter_u64_fetch(z->uz_frees);
5417 	xdomain += counter_u64_fetch(z->uz_xdomain);
5418 	sleeps += z->uz_sleeps;
5419 	if (cachefreep != NULL)
5420 		*cachefreep = cachefree;
5421 	if (allocsp != NULL)
5422 		*allocsp = allocs;
5423 	if (freesp != NULL)
5424 		*freesp = frees;
5425 	if (sleepsp != NULL)
5426 		*sleepsp = sleeps;
5427 	if (xdomainp != NULL)
5428 		*xdomainp = xdomain;
5429 }
5430 #endif /* DDB */
5431 
5432 static int
5433 sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS)
5434 {
5435 	uma_keg_t kz;
5436 	uma_zone_t z;
5437 	int count;
5438 
5439 	count = 0;
5440 	rw_rlock(&uma_rwlock);
5441 	LIST_FOREACH(kz, &uma_kegs, uk_link) {
5442 		LIST_FOREACH(z, &kz->uk_zones, uz_link)
5443 			count++;
5444 	}
5445 	LIST_FOREACH(z, &uma_cachezones, uz_link)
5446 		count++;
5447 
5448 	rw_runlock(&uma_rwlock);
5449 	return (sysctl_handle_int(oidp, &count, 0, req));
5450 }
5451 
5452 static void
5453 uma_vm_zone_stats(struct uma_type_header *uth, uma_zone_t z, struct sbuf *sbuf,
5454     struct uma_percpu_stat *ups, bool internal)
5455 {
5456 	uma_zone_domain_t zdom;
5457 	uma_cache_t cache;
5458 	int i;
5459 
5460 	for (i = 0; i < vm_ndomains; i++) {
5461 		zdom = ZDOM_GET(z, i);
5462 		uth->uth_zone_free += zdom->uzd_nitems;
5463 	}
5464 	uth->uth_allocs = counter_u64_fetch(z->uz_allocs);
5465 	uth->uth_frees = counter_u64_fetch(z->uz_frees);
5466 	uth->uth_fails = counter_u64_fetch(z->uz_fails);
5467 	uth->uth_xdomain = counter_u64_fetch(z->uz_xdomain);
5468 	uth->uth_sleeps = z->uz_sleeps;
5469 
5470 	for (i = 0; i < mp_maxid + 1; i++) {
5471 		bzero(&ups[i], sizeof(*ups));
5472 		if (internal || CPU_ABSENT(i))
5473 			continue;
5474 		cache = &z->uz_cpu[i];
5475 		ups[i].ups_cache_free += cache->uc_allocbucket.ucb_cnt;
5476 		ups[i].ups_cache_free += cache->uc_freebucket.ucb_cnt;
5477 		ups[i].ups_cache_free += cache->uc_crossbucket.ucb_cnt;
5478 		ups[i].ups_allocs = cache->uc_allocs;
5479 		ups[i].ups_frees = cache->uc_frees;
5480 	}
5481 }
5482 
5483 static int
5484 sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS)
5485 {
5486 	struct uma_stream_header ush;
5487 	struct uma_type_header uth;
5488 	struct uma_percpu_stat *ups;
5489 	struct sbuf sbuf;
5490 	uma_keg_t kz;
5491 	uma_zone_t z;
5492 	uint64_t items;
5493 	uint32_t kfree, pages;
5494 	int count, error, i;
5495 
5496 	error = sysctl_wire_old_buffer(req, 0);
5497 	if (error != 0)
5498 		return (error);
5499 	sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
5500 	sbuf_clear_flags(&sbuf, SBUF_INCLUDENUL);
5501 	ups = malloc((mp_maxid + 1) * sizeof(*ups), M_TEMP, M_WAITOK);
5502 
5503 	count = 0;
5504 	rw_rlock(&uma_rwlock);
5505 	LIST_FOREACH(kz, &uma_kegs, uk_link) {
5506 		LIST_FOREACH(z, &kz->uk_zones, uz_link)
5507 			count++;
5508 	}
5509 
5510 	LIST_FOREACH(z, &uma_cachezones, uz_link)
5511 		count++;
5512 
5513 	/*
5514 	 * Insert stream header.
5515 	 */
5516 	bzero(&ush, sizeof(ush));
5517 	ush.ush_version = UMA_STREAM_VERSION;
5518 	ush.ush_maxcpus = (mp_maxid + 1);
5519 	ush.ush_count = count;
5520 	(void)sbuf_bcat(&sbuf, &ush, sizeof(ush));
5521 
5522 	LIST_FOREACH(kz, &uma_kegs, uk_link) {
5523 		kfree = pages = 0;
5524 		for (i = 0; i < vm_ndomains; i++) {
5525 			kfree += kz->uk_domain[i].ud_free_items;
5526 			pages += kz->uk_domain[i].ud_pages;
5527 		}
5528 		LIST_FOREACH(z, &kz->uk_zones, uz_link) {
5529 			bzero(&uth, sizeof(uth));
5530 			strlcpy(uth.uth_name, z->uz_name, UTH_MAX_NAME);
5531 			uth.uth_align = kz->uk_align;
5532 			uth.uth_size = kz->uk_size;
5533 			uth.uth_rsize = kz->uk_rsize;
5534 			if (z->uz_max_items > 0) {
5535 				items = UZ_ITEMS_COUNT(z->uz_items);
5536 				uth.uth_pages = (items / kz->uk_ipers) *
5537 					kz->uk_ppera;
5538 			} else
5539 				uth.uth_pages = pages;
5540 			uth.uth_maxpages = (z->uz_max_items / kz->uk_ipers) *
5541 			    kz->uk_ppera;
5542 			uth.uth_limit = z->uz_max_items;
5543 			uth.uth_keg_free = kfree;
5544 
5545 			/*
5546 			 * A zone is secondary is it is not the first entry
5547 			 * on the keg's zone list.
5548 			 */
5549 			if ((z->uz_flags & UMA_ZONE_SECONDARY) &&
5550 			    (LIST_FIRST(&kz->uk_zones) != z))
5551 				uth.uth_zone_flags = UTH_ZONE_SECONDARY;
5552 			uma_vm_zone_stats(&uth, z, &sbuf, ups,
5553 			    kz->uk_flags & UMA_ZFLAG_INTERNAL);
5554 			(void)sbuf_bcat(&sbuf, &uth, sizeof(uth));
5555 			for (i = 0; i < mp_maxid + 1; i++)
5556 				(void)sbuf_bcat(&sbuf, &ups[i], sizeof(ups[i]));
5557 		}
5558 	}
5559 	LIST_FOREACH(z, &uma_cachezones, uz_link) {
5560 		bzero(&uth, sizeof(uth));
5561 		strlcpy(uth.uth_name, z->uz_name, UTH_MAX_NAME);
5562 		uth.uth_size = z->uz_size;
5563 		uma_vm_zone_stats(&uth, z, &sbuf, ups, false);
5564 		(void)sbuf_bcat(&sbuf, &uth, sizeof(uth));
5565 		for (i = 0; i < mp_maxid + 1; i++)
5566 			(void)sbuf_bcat(&sbuf, &ups[i], sizeof(ups[i]));
5567 	}
5568 
5569 	rw_runlock(&uma_rwlock);
5570 	error = sbuf_finish(&sbuf);
5571 	sbuf_delete(&sbuf);
5572 	free(ups, M_TEMP);
5573 	return (error);
5574 }
5575 
5576 int
5577 sysctl_handle_uma_zone_max(SYSCTL_HANDLER_ARGS)
5578 {
5579 	uma_zone_t zone = *(uma_zone_t *)arg1;
5580 	int error, max;
5581 
5582 	max = uma_zone_get_max(zone);
5583 	error = sysctl_handle_int(oidp, &max, 0, req);
5584 	if (error || !req->newptr)
5585 		return (error);
5586 
5587 	uma_zone_set_max(zone, max);
5588 
5589 	return (0);
5590 }
5591 
5592 int
5593 sysctl_handle_uma_zone_cur(SYSCTL_HANDLER_ARGS)
5594 {
5595 	uma_zone_t zone;
5596 	int cur;
5597 
5598 	/*
5599 	 * Some callers want to add sysctls for global zones that
5600 	 * may not yet exist so they pass a pointer to a pointer.
5601 	 */
5602 	if (arg2 == 0)
5603 		zone = *(uma_zone_t *)arg1;
5604 	else
5605 		zone = arg1;
5606 	cur = uma_zone_get_cur(zone);
5607 	return (sysctl_handle_int(oidp, &cur, 0, req));
5608 }
5609 
5610 static int
5611 sysctl_handle_uma_zone_allocs(SYSCTL_HANDLER_ARGS)
5612 {
5613 	uma_zone_t zone = arg1;
5614 	uint64_t cur;
5615 
5616 	cur = uma_zone_get_allocs(zone);
5617 	return (sysctl_handle_64(oidp, &cur, 0, req));
5618 }
5619 
5620 static int
5621 sysctl_handle_uma_zone_frees(SYSCTL_HANDLER_ARGS)
5622 {
5623 	uma_zone_t zone = arg1;
5624 	uint64_t cur;
5625 
5626 	cur = uma_zone_get_frees(zone);
5627 	return (sysctl_handle_64(oidp, &cur, 0, req));
5628 }
5629 
5630 static int
5631 sysctl_handle_uma_zone_flags(SYSCTL_HANDLER_ARGS)
5632 {
5633 	struct sbuf sbuf;
5634 	uma_zone_t zone = arg1;
5635 	int error;
5636 
5637 	sbuf_new_for_sysctl(&sbuf, NULL, 0, req);
5638 	if (zone->uz_flags != 0)
5639 		sbuf_printf(&sbuf, "0x%b", zone->uz_flags, PRINT_UMA_ZFLAGS);
5640 	else
5641 		sbuf_printf(&sbuf, "0");
5642 	error = sbuf_finish(&sbuf);
5643 	sbuf_delete(&sbuf);
5644 
5645 	return (error);
5646 }
5647 
5648 static int
5649 sysctl_handle_uma_slab_efficiency(SYSCTL_HANDLER_ARGS)
5650 {
5651 	uma_keg_t keg = arg1;
5652 	int avail, effpct, total;
5653 
5654 	total = keg->uk_ppera * PAGE_SIZE;
5655 	if ((keg->uk_flags & UMA_ZFLAG_OFFPAGE) != 0)
5656 		total += slabzone(keg->uk_ipers)->uz_keg->uk_rsize;
5657 	/*
5658 	 * We consider the client's requested size and alignment here, not the
5659 	 * real size determination uk_rsize, because we also adjust the real
5660 	 * size for internal implementation reasons (max bitset size).
5661 	 */
5662 	avail = keg->uk_ipers * roundup2(keg->uk_size, keg->uk_align + 1);
5663 	if ((keg->uk_flags & UMA_ZONE_PCPU) != 0)
5664 		avail *= mp_maxid + 1;
5665 	effpct = 100 * avail / total;
5666 	return (sysctl_handle_int(oidp, &effpct, 0, req));
5667 }
5668 
5669 static int
5670 sysctl_handle_uma_zone_items(SYSCTL_HANDLER_ARGS)
5671 {
5672 	uma_zone_t zone = arg1;
5673 	uint64_t cur;
5674 
5675 	cur = UZ_ITEMS_COUNT(atomic_load_64(&zone->uz_items));
5676 	return (sysctl_handle_64(oidp, &cur, 0, req));
5677 }
5678 
5679 #ifdef INVARIANTS
5680 static uma_slab_t
5681 uma_dbg_getslab(uma_zone_t zone, void *item)
5682 {
5683 	uma_slab_t slab;
5684 	uma_keg_t keg;
5685 	uint8_t *mem;
5686 
5687 	/*
5688 	 * It is safe to return the slab here even though the
5689 	 * zone is unlocked because the item's allocation state
5690 	 * essentially holds a reference.
5691 	 */
5692 	mem = (uint8_t *)((uintptr_t)item & (~UMA_SLAB_MASK));
5693 	if ((zone->uz_flags & UMA_ZFLAG_CACHE) != 0)
5694 		return (NULL);
5695 	if (zone->uz_flags & UMA_ZFLAG_VTOSLAB)
5696 		return (vtoslab((vm_offset_t)mem));
5697 	keg = zone->uz_keg;
5698 	if ((keg->uk_flags & UMA_ZFLAG_HASH) == 0)
5699 		return ((uma_slab_t)(mem + keg->uk_pgoff));
5700 	KEG_LOCK(keg, 0);
5701 	slab = hash_sfind(&keg->uk_hash, mem);
5702 	KEG_UNLOCK(keg, 0);
5703 
5704 	return (slab);
5705 }
5706 
5707 static bool
5708 uma_dbg_zskip(uma_zone_t zone, void *mem)
5709 {
5710 
5711 	if ((zone->uz_flags & UMA_ZFLAG_CACHE) != 0)
5712 		return (true);
5713 
5714 	return (uma_dbg_kskip(zone->uz_keg, mem));
5715 }
5716 
5717 static bool
5718 uma_dbg_kskip(uma_keg_t keg, void *mem)
5719 {
5720 	uintptr_t idx;
5721 
5722 	if (dbg_divisor == 0)
5723 		return (true);
5724 
5725 	if (dbg_divisor == 1)
5726 		return (false);
5727 
5728 	idx = (uintptr_t)mem >> PAGE_SHIFT;
5729 	if (keg->uk_ipers > 1) {
5730 		idx *= keg->uk_ipers;
5731 		idx += ((uintptr_t)mem & PAGE_MASK) / keg->uk_rsize;
5732 	}
5733 
5734 	if ((idx / dbg_divisor) * dbg_divisor != idx) {
5735 		counter_u64_add(uma_skip_cnt, 1);
5736 		return (true);
5737 	}
5738 	counter_u64_add(uma_dbg_cnt, 1);
5739 
5740 	return (false);
5741 }
5742 
5743 /*
5744  * Set up the slab's freei data such that uma_dbg_free can function.
5745  *
5746  */
5747 static void
5748 uma_dbg_alloc(uma_zone_t zone, uma_slab_t slab, void *item)
5749 {
5750 	uma_keg_t keg;
5751 	int freei;
5752 
5753 	if (slab == NULL) {
5754 		slab = uma_dbg_getslab(zone, item);
5755 		if (slab == NULL)
5756 			panic("uma: item %p did not belong to zone %s",
5757 			    item, zone->uz_name);
5758 	}
5759 	keg = zone->uz_keg;
5760 	freei = slab_item_index(slab, keg, item);
5761 
5762 	if (BIT_TEST_SET_ATOMIC(keg->uk_ipers, freei,
5763 	    slab_dbg_bits(slab, keg)))
5764 		panic("Duplicate alloc of %p from zone %p(%s) slab %p(%d)",
5765 		    item, zone, zone->uz_name, slab, freei);
5766 }
5767 
5768 /*
5769  * Verifies freed addresses.  Checks for alignment, valid slab membership
5770  * and duplicate frees.
5771  *
5772  */
5773 static void
5774 uma_dbg_free(uma_zone_t zone, uma_slab_t slab, void *item)
5775 {
5776 	uma_keg_t keg;
5777 	int freei;
5778 
5779 	if (slab == NULL) {
5780 		slab = uma_dbg_getslab(zone, item);
5781 		if (slab == NULL)
5782 			panic("uma: Freed item %p did not belong to zone %s",
5783 			    item, zone->uz_name);
5784 	}
5785 	keg = zone->uz_keg;
5786 	freei = slab_item_index(slab, keg, item);
5787 
5788 	if (freei >= keg->uk_ipers)
5789 		panic("Invalid free of %p from zone %p(%s) slab %p(%d)",
5790 		    item, zone, zone->uz_name, slab, freei);
5791 
5792 	if (slab_item(slab, keg, freei) != item)
5793 		panic("Unaligned free of %p from zone %p(%s) slab %p(%d)",
5794 		    item, zone, zone->uz_name, slab, freei);
5795 
5796 	if (!BIT_TEST_CLR_ATOMIC(keg->uk_ipers, freei,
5797 	    slab_dbg_bits(slab, keg)))
5798 		panic("Duplicate free of %p from zone %p(%s) slab %p(%d)",
5799 		    item, zone, zone->uz_name, slab, freei);
5800 }
5801 #endif /* INVARIANTS */
5802 
5803 #ifdef DDB
5804 static int64_t
5805 get_uma_stats(uma_keg_t kz, uma_zone_t z, uint64_t *allocs, uint64_t *used,
5806     uint64_t *sleeps, long *cachefree, uint64_t *xdomain)
5807 {
5808 	uint64_t frees;
5809 	int i;
5810 
5811 	if (kz->uk_flags & UMA_ZFLAG_INTERNAL) {
5812 		*allocs = counter_u64_fetch(z->uz_allocs);
5813 		frees = counter_u64_fetch(z->uz_frees);
5814 		*sleeps = z->uz_sleeps;
5815 		*cachefree = 0;
5816 		*xdomain = 0;
5817 	} else
5818 		uma_zone_sumstat(z, cachefree, allocs, &frees, sleeps,
5819 		    xdomain);
5820 	for (i = 0; i < vm_ndomains; i++) {
5821 		*cachefree += ZDOM_GET(z, i)->uzd_nitems;
5822 		if (!((z->uz_flags & UMA_ZONE_SECONDARY) &&
5823 		    (LIST_FIRST(&kz->uk_zones) != z)))
5824 			*cachefree += kz->uk_domain[i].ud_free_items;
5825 	}
5826 	*used = *allocs - frees;
5827 	return (((int64_t)*used + *cachefree) * kz->uk_size);
5828 }
5829 
5830 DB_SHOW_COMMAND_FLAGS(uma, db_show_uma, DB_CMD_MEMSAFE)
5831 {
5832 	const char *fmt_hdr, *fmt_entry;
5833 	uma_keg_t kz;
5834 	uma_zone_t z;
5835 	uint64_t allocs, used, sleeps, xdomain;
5836 	long cachefree;
5837 	/* variables for sorting */
5838 	uma_keg_t cur_keg;
5839 	uma_zone_t cur_zone, last_zone;
5840 	int64_t cur_size, last_size, size;
5841 	int ties;
5842 
5843 	/* /i option produces machine-parseable CSV output */
5844 	if (modif[0] == 'i') {
5845 		fmt_hdr = "%s,%s,%s,%s,%s,%s,%s,%s,%s\n";
5846 		fmt_entry = "\"%s\",%ju,%jd,%ld,%ju,%ju,%u,%jd,%ju\n";
5847 	} else {
5848 		fmt_hdr = "%18s %6s %7s %7s %11s %7s %7s %10s %8s\n";
5849 		fmt_entry = "%18s %6ju %7jd %7ld %11ju %7ju %7u %10jd %8ju\n";
5850 	}
5851 
5852 	db_printf(fmt_hdr, "Zone", "Size", "Used", "Free", "Requests",
5853 	    "Sleeps", "Bucket", "Total Mem", "XFree");
5854 
5855 	/* Sort the zones with largest size first. */
5856 	last_zone = NULL;
5857 	last_size = INT64_MAX;
5858 	for (;;) {
5859 		cur_zone = NULL;
5860 		cur_size = -1;
5861 		ties = 0;
5862 		LIST_FOREACH(kz, &uma_kegs, uk_link) {
5863 			LIST_FOREACH(z, &kz->uk_zones, uz_link) {
5864 				/*
5865 				 * In the case of size ties, print out zones
5866 				 * in the order they are encountered.  That is,
5867 				 * when we encounter the most recently output
5868 				 * zone, we have already printed all preceding
5869 				 * ties, and we must print all following ties.
5870 				 */
5871 				if (z == last_zone) {
5872 					ties = 1;
5873 					continue;
5874 				}
5875 				size = get_uma_stats(kz, z, &allocs, &used,
5876 				    &sleeps, &cachefree, &xdomain);
5877 				if (size > cur_size && size < last_size + ties)
5878 				{
5879 					cur_size = size;
5880 					cur_zone = z;
5881 					cur_keg = kz;
5882 				}
5883 			}
5884 		}
5885 		if (cur_zone == NULL)
5886 			break;
5887 
5888 		size = get_uma_stats(cur_keg, cur_zone, &allocs, &used,
5889 		    &sleeps, &cachefree, &xdomain);
5890 		db_printf(fmt_entry, cur_zone->uz_name,
5891 		    (uintmax_t)cur_keg->uk_size, (intmax_t)used, cachefree,
5892 		    (uintmax_t)allocs, (uintmax_t)sleeps,
5893 		    (unsigned)cur_zone->uz_bucket_size, (intmax_t)size,
5894 		    xdomain);
5895 
5896 		if (db_pager_quit)
5897 			return;
5898 		last_zone = cur_zone;
5899 		last_size = cur_size;
5900 	}
5901 }
5902 
5903 DB_SHOW_COMMAND_FLAGS(umacache, db_show_umacache, DB_CMD_MEMSAFE)
5904 {
5905 	uma_zone_t z;
5906 	uint64_t allocs, frees;
5907 	long cachefree;
5908 	int i;
5909 
5910 	db_printf("%18s %8s %8s %8s %12s %8s\n", "Zone", "Size", "Used", "Free",
5911 	    "Requests", "Bucket");
5912 	LIST_FOREACH(z, &uma_cachezones, uz_link) {
5913 		uma_zone_sumstat(z, &cachefree, &allocs, &frees, NULL, NULL);
5914 		for (i = 0; i < vm_ndomains; i++)
5915 			cachefree += ZDOM_GET(z, i)->uzd_nitems;
5916 		db_printf("%18s %8ju %8jd %8ld %12ju %8u\n",
5917 		    z->uz_name, (uintmax_t)z->uz_size,
5918 		    (intmax_t)(allocs - frees), cachefree,
5919 		    (uintmax_t)allocs, z->uz_bucket_size);
5920 		if (db_pager_quit)
5921 			return;
5922 	}
5923 }
5924 #endif	/* DDB */
5925