xref: /freebsd/sys/vm/uma_core.c (revision c03c5b1c)
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 callout uma_callout;
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 *);
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 *unused)
1111 {
1112 	bucket_enable();
1113 	zone_foreach(zone_timeout, NULL);
1114 
1115 	/* Reschedule this event */
1116 	callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL);
1117 }
1118 
1119 /*
1120  * Update the working set size estimates for the zone's bucket cache.
1121  * The constants chosen here are somewhat arbitrary.
1122  */
1123 static void
1124 zone_domain_update_wss(uma_zone_domain_t zdom)
1125 {
1126 	long m;
1127 
1128 	ZDOM_LOCK_ASSERT(zdom);
1129 	MPASS(zdom->uzd_imax >= zdom->uzd_nitems);
1130 	MPASS(zdom->uzd_nitems >= zdom->uzd_bimin);
1131 	MPASS(zdom->uzd_bimin >= zdom->uzd_imin);
1132 
1133 	/*
1134 	 * Estimate WSS as modified moving average of biggest allocation
1135 	 * batches for each period over few minutes (UMA_TIMEOUT of 20s).
1136 	 */
1137 	zdom->uzd_wss = lmax(zdom->uzd_wss * 3 / 4,
1138 	    zdom->uzd_imax - zdom->uzd_bimin);
1139 
1140 	/*
1141 	 * Estimate longtime minimum item count as a combination of recent
1142 	 * minimum item count, adjusted by WSS for safety, and the modified
1143 	 * moving average over the last several hours (UMA_TIMEOUT of 20s).
1144 	 * timin measures time since limin tried to go negative, that means
1145 	 * we were dangerously close to or got out of cache.
1146 	 */
1147 	m = zdom->uzd_imin - zdom->uzd_wss;
1148 	if (m >= 0) {
1149 		if (zdom->uzd_limin >= m)
1150 			zdom->uzd_limin = m;
1151 		else
1152 			zdom->uzd_limin = (m + zdom->uzd_limin * 255) / 256;
1153 		zdom->uzd_timin++;
1154 	} else {
1155 		zdom->uzd_limin = 0;
1156 		zdom->uzd_timin = 0;
1157 	}
1158 
1159 	/* To reduce period edge effects on WSS keep half of the imax. */
1160 	atomic_subtract_long(&zdom->uzd_imax,
1161 	    (zdom->uzd_imax - zdom->uzd_nitems + 1) / 2);
1162 	zdom->uzd_imin = zdom->uzd_bimin = zdom->uzd_nitems;
1163 }
1164 
1165 /*
1166  * Routine to perform timeout driven calculations.  This expands the
1167  * hashes and does per cpu statistics aggregation.
1168  *
1169  *  Returns nothing.
1170  */
1171 static void
1172 zone_timeout(uma_zone_t zone, void *unused)
1173 {
1174 	uma_keg_t keg;
1175 	u_int slabs, pages;
1176 
1177 	if ((zone->uz_flags & UMA_ZFLAG_HASH) == 0)
1178 		goto trim;
1179 
1180 	keg = zone->uz_keg;
1181 
1182 	/*
1183 	 * Hash zones are non-numa by definition so the first domain
1184 	 * is the only one present.
1185 	 */
1186 	KEG_LOCK(keg, 0);
1187 	pages = keg->uk_domain[0].ud_pages;
1188 
1189 	/*
1190 	 * Expand the keg hash table.
1191 	 *
1192 	 * This is done if the number of slabs is larger than the hash size.
1193 	 * What I'm trying to do here is completely reduce collisions.  This
1194 	 * may be a little aggressive.  Should I allow for two collisions max?
1195 	 */
1196 	if ((slabs = pages / keg->uk_ppera) > keg->uk_hash.uh_hashsize) {
1197 		struct uma_hash newhash;
1198 		struct uma_hash oldhash;
1199 		int ret;
1200 
1201 		/*
1202 		 * This is so involved because allocating and freeing
1203 		 * while the keg lock is held will lead to deadlock.
1204 		 * I have to do everything in stages and check for
1205 		 * races.
1206 		 */
1207 		KEG_UNLOCK(keg, 0);
1208 		ret = hash_alloc(&newhash, 1 << fls(slabs));
1209 		KEG_LOCK(keg, 0);
1210 		if (ret) {
1211 			if (hash_expand(&keg->uk_hash, &newhash)) {
1212 				oldhash = keg->uk_hash;
1213 				keg->uk_hash = newhash;
1214 			} else
1215 				oldhash = newhash;
1216 
1217 			KEG_UNLOCK(keg, 0);
1218 			hash_free(&oldhash);
1219 			goto trim;
1220 		}
1221 	}
1222 	KEG_UNLOCK(keg, 0);
1223 
1224 trim:
1225 	/* Trim caches not used for a long time. */
1226 	if ((zone->uz_flags & UMA_ZONE_UNMANAGED) == 0) {
1227 		for (int i = 0; i < vm_ndomains; i++) {
1228 			if (bucket_cache_reclaim_domain(zone, false, false, i) &&
1229 			    (zone->uz_flags & UMA_ZFLAG_CACHE) == 0)
1230 				keg_drain(zone->uz_keg, i);
1231 		}
1232 	}
1233 }
1234 
1235 /*
1236  * Allocate and zero fill the next sized hash table from the appropriate
1237  * backing store.
1238  *
1239  * Arguments:
1240  *	hash  A new hash structure with the old hash size in uh_hashsize
1241  *
1242  * Returns:
1243  *	1 on success and 0 on failure.
1244  */
1245 static int
1246 hash_alloc(struct uma_hash *hash, u_int size)
1247 {
1248 	size_t alloc;
1249 
1250 	KASSERT(powerof2(size), ("hash size must be power of 2"));
1251 	if (size > UMA_HASH_SIZE_INIT)  {
1252 		hash->uh_hashsize = size;
1253 		alloc = sizeof(hash->uh_slab_hash[0]) * hash->uh_hashsize;
1254 		hash->uh_slab_hash = malloc(alloc, M_UMAHASH, M_NOWAIT);
1255 	} else {
1256 		alloc = sizeof(hash->uh_slab_hash[0]) * UMA_HASH_SIZE_INIT;
1257 		hash->uh_slab_hash = zone_alloc_item(hashzone, NULL,
1258 		    UMA_ANYDOMAIN, M_WAITOK);
1259 		hash->uh_hashsize = UMA_HASH_SIZE_INIT;
1260 	}
1261 	if (hash->uh_slab_hash) {
1262 		bzero(hash->uh_slab_hash, alloc);
1263 		hash->uh_hashmask = hash->uh_hashsize - 1;
1264 		return (1);
1265 	}
1266 
1267 	return (0);
1268 }
1269 
1270 /*
1271  * Expands the hash table for HASH zones.  This is done from zone_timeout
1272  * to reduce collisions.  This must not be done in the regular allocation
1273  * path, otherwise, we can recurse on the vm while allocating pages.
1274  *
1275  * Arguments:
1276  *	oldhash  The hash you want to expand
1277  *	newhash  The hash structure for the new table
1278  *
1279  * Returns:
1280  *	Nothing
1281  *
1282  * Discussion:
1283  */
1284 static int
1285 hash_expand(struct uma_hash *oldhash, struct uma_hash *newhash)
1286 {
1287 	uma_hash_slab_t slab;
1288 	u_int hval;
1289 	u_int idx;
1290 
1291 	if (!newhash->uh_slab_hash)
1292 		return (0);
1293 
1294 	if (oldhash->uh_hashsize >= newhash->uh_hashsize)
1295 		return (0);
1296 
1297 	/*
1298 	 * I need to investigate hash algorithms for resizing without a
1299 	 * full rehash.
1300 	 */
1301 
1302 	for (idx = 0; idx < oldhash->uh_hashsize; idx++)
1303 		while (!LIST_EMPTY(&oldhash->uh_slab_hash[idx])) {
1304 			slab = LIST_FIRST(&oldhash->uh_slab_hash[idx]);
1305 			LIST_REMOVE(slab, uhs_hlink);
1306 			hval = UMA_HASH(newhash, slab->uhs_data);
1307 			LIST_INSERT_HEAD(&newhash->uh_slab_hash[hval],
1308 			    slab, uhs_hlink);
1309 		}
1310 
1311 	return (1);
1312 }
1313 
1314 /*
1315  * Free the hash bucket to the appropriate backing store.
1316  *
1317  * Arguments:
1318  *	slab_hash  The hash bucket we're freeing
1319  *	hashsize   The number of entries in that hash bucket
1320  *
1321  * Returns:
1322  *	Nothing
1323  */
1324 static void
1325 hash_free(struct uma_hash *hash)
1326 {
1327 	if (hash->uh_slab_hash == NULL)
1328 		return;
1329 	if (hash->uh_hashsize == UMA_HASH_SIZE_INIT)
1330 		zone_free_item(hashzone, hash->uh_slab_hash, NULL, SKIP_NONE);
1331 	else
1332 		free(hash->uh_slab_hash, M_UMAHASH);
1333 }
1334 
1335 /*
1336  * Frees all outstanding items in a bucket
1337  *
1338  * Arguments:
1339  *	zone   The zone to free to, must be unlocked.
1340  *	bucket The free/alloc bucket with items.
1341  *
1342  * Returns:
1343  *	Nothing
1344  */
1345 static void
1346 bucket_drain(uma_zone_t zone, uma_bucket_t bucket)
1347 {
1348 	int i;
1349 
1350 	if (bucket->ub_cnt == 0)
1351 		return;
1352 
1353 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0 &&
1354 	    bucket->ub_seq != SMR_SEQ_INVALID) {
1355 		smr_wait(zone->uz_smr, bucket->ub_seq);
1356 		bucket->ub_seq = SMR_SEQ_INVALID;
1357 		for (i = 0; i < bucket->ub_cnt; i++)
1358 			item_dtor(zone, bucket->ub_bucket[i],
1359 			    zone->uz_size, NULL, SKIP_NONE);
1360 	}
1361 	if (zone->uz_fini)
1362 		for (i = 0; i < bucket->ub_cnt; i++) {
1363 			kasan_mark_item_valid(zone, bucket->ub_bucket[i]);
1364 			zone->uz_fini(bucket->ub_bucket[i], zone->uz_size);
1365 			kasan_mark_item_invalid(zone, bucket->ub_bucket[i]);
1366 		}
1367 	zone->uz_release(zone->uz_arg, bucket->ub_bucket, bucket->ub_cnt);
1368 	if (zone->uz_max_items > 0)
1369 		zone_free_limit(zone, bucket->ub_cnt);
1370 #ifdef INVARIANTS
1371 	bzero(bucket->ub_bucket, sizeof(void *) * bucket->ub_cnt);
1372 #endif
1373 	bucket->ub_cnt = 0;
1374 }
1375 
1376 /*
1377  * Drains the per cpu caches for a zone.
1378  *
1379  * NOTE: This may only be called while the zone is being torn down, and not
1380  * during normal operation.  This is necessary in order that we do not have
1381  * to migrate CPUs to drain the per-CPU caches.
1382  *
1383  * Arguments:
1384  *	zone     The zone to drain, must be unlocked.
1385  *
1386  * Returns:
1387  *	Nothing
1388  */
1389 static void
1390 cache_drain(uma_zone_t zone)
1391 {
1392 	uma_cache_t cache;
1393 	uma_bucket_t bucket;
1394 	smr_seq_t seq;
1395 	int cpu;
1396 
1397 	/*
1398 	 * XXX: It is safe to not lock the per-CPU caches, because we're
1399 	 * tearing down the zone anyway.  I.e., there will be no further use
1400 	 * of the caches at this point.
1401 	 *
1402 	 * XXX: It would good to be able to assert that the zone is being
1403 	 * torn down to prevent improper use of cache_drain().
1404 	 */
1405 	seq = SMR_SEQ_INVALID;
1406 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0)
1407 		seq = smr_advance(zone->uz_smr);
1408 	CPU_FOREACH(cpu) {
1409 		cache = &zone->uz_cpu[cpu];
1410 		bucket = cache_bucket_unload_alloc(cache);
1411 		if (bucket != NULL)
1412 			bucket_free(zone, bucket, NULL);
1413 		bucket = cache_bucket_unload_free(cache);
1414 		if (bucket != NULL) {
1415 			bucket->ub_seq = seq;
1416 			bucket_free(zone, bucket, NULL);
1417 		}
1418 		bucket = cache_bucket_unload_cross(cache);
1419 		if (bucket != NULL) {
1420 			bucket->ub_seq = seq;
1421 			bucket_free(zone, bucket, NULL);
1422 		}
1423 	}
1424 	bucket_cache_reclaim(zone, true, UMA_ANYDOMAIN);
1425 }
1426 
1427 static void
1428 cache_shrink(uma_zone_t zone, void *unused)
1429 {
1430 
1431 	if (zone->uz_flags & UMA_ZFLAG_INTERNAL)
1432 		return;
1433 
1434 	ZONE_LOCK(zone);
1435 	zone->uz_bucket_size =
1436 	    (zone->uz_bucket_size_min + zone->uz_bucket_size) / 2;
1437 	ZONE_UNLOCK(zone);
1438 }
1439 
1440 static void
1441 cache_drain_safe_cpu(uma_zone_t zone, void *unused)
1442 {
1443 	uma_cache_t cache;
1444 	uma_bucket_t b1, b2, b3;
1445 	int domain;
1446 
1447 	if (zone->uz_flags & UMA_ZFLAG_INTERNAL)
1448 		return;
1449 
1450 	b1 = b2 = b3 = NULL;
1451 	critical_enter();
1452 	cache = &zone->uz_cpu[curcpu];
1453 	domain = PCPU_GET(domain);
1454 	b1 = cache_bucket_unload_alloc(cache);
1455 
1456 	/*
1457 	 * Don't flush SMR zone buckets.  This leaves the zone without a
1458 	 * bucket and forces every free to synchronize().
1459 	 */
1460 	if ((zone->uz_flags & UMA_ZONE_SMR) == 0) {
1461 		b2 = cache_bucket_unload_free(cache);
1462 		b3 = cache_bucket_unload_cross(cache);
1463 	}
1464 	critical_exit();
1465 
1466 	if (b1 != NULL)
1467 		zone_free_bucket(zone, b1, NULL, domain, false);
1468 	if (b2 != NULL)
1469 		zone_free_bucket(zone, b2, NULL, domain, false);
1470 	if (b3 != NULL) {
1471 		/* Adjust the domain so it goes to zone_free_cross. */
1472 		domain = (domain + 1) % vm_ndomains;
1473 		zone_free_bucket(zone, b3, NULL, domain, false);
1474 	}
1475 }
1476 
1477 /*
1478  * Safely drain per-CPU caches of a zone(s) to alloc bucket.
1479  * This is an expensive call because it needs to bind to all CPUs
1480  * one by one and enter a critical section on each of them in order
1481  * to safely access their cache buckets.
1482  * Zone lock must not be held on call this function.
1483  */
1484 static void
1485 pcpu_cache_drain_safe(uma_zone_t zone)
1486 {
1487 	int cpu;
1488 
1489 	/*
1490 	 * Polite bucket sizes shrinking was not enough, shrink aggressively.
1491 	 */
1492 	if (zone)
1493 		cache_shrink(zone, NULL);
1494 	else
1495 		zone_foreach(cache_shrink, NULL);
1496 
1497 	CPU_FOREACH(cpu) {
1498 		thread_lock(curthread);
1499 		sched_bind(curthread, cpu);
1500 		thread_unlock(curthread);
1501 
1502 		if (zone)
1503 			cache_drain_safe_cpu(zone, NULL);
1504 		else
1505 			zone_foreach(cache_drain_safe_cpu, NULL);
1506 	}
1507 	thread_lock(curthread);
1508 	sched_unbind(curthread);
1509 	thread_unlock(curthread);
1510 }
1511 
1512 /*
1513  * Reclaim cached buckets from a zone.  All buckets are reclaimed if the caller
1514  * requested a drain, otherwise the per-domain caches are trimmed to either
1515  * estimated working set size.
1516  */
1517 static bool
1518 bucket_cache_reclaim_domain(uma_zone_t zone, bool drain, bool trim, int domain)
1519 {
1520 	uma_zone_domain_t zdom;
1521 	uma_bucket_t bucket;
1522 	long target;
1523 	bool done = false;
1524 
1525 	/*
1526 	 * The cross bucket is partially filled and not part of
1527 	 * the item count.  Reclaim it individually here.
1528 	 */
1529 	zdom = ZDOM_GET(zone, domain);
1530 	if ((zone->uz_flags & UMA_ZONE_SMR) == 0 || drain) {
1531 		ZONE_CROSS_LOCK(zone);
1532 		bucket = zdom->uzd_cross;
1533 		zdom->uzd_cross = NULL;
1534 		ZONE_CROSS_UNLOCK(zone);
1535 		if (bucket != NULL)
1536 			bucket_free(zone, bucket, NULL);
1537 	}
1538 
1539 	/*
1540 	 * If we were asked to drain the zone, we are done only once
1541 	 * this bucket cache is empty.  If trim, we reclaim items in
1542 	 * excess of the zone's estimated working set size.  Multiple
1543 	 * consecutive calls will shrink the WSS and so reclaim more.
1544 	 * If neither drain nor trim, then voluntarily reclaim 1/4
1545 	 * (to reduce first spike) of items not used for a long time.
1546 	 */
1547 	ZDOM_LOCK(zdom);
1548 	zone_domain_update_wss(zdom);
1549 	if (drain)
1550 		target = 0;
1551 	else if (trim)
1552 		target = zdom->uzd_wss;
1553 	else if (zdom->uzd_timin > 900 / UMA_TIMEOUT)
1554 		target = zdom->uzd_nitems - zdom->uzd_limin / 4;
1555 	else {
1556 		ZDOM_UNLOCK(zdom);
1557 		return (done);
1558 	}
1559 	while ((bucket = STAILQ_FIRST(&zdom->uzd_buckets)) != NULL &&
1560 	    zdom->uzd_nitems >= target + bucket->ub_cnt) {
1561 		bucket = zone_fetch_bucket(zone, zdom, true);
1562 		if (bucket == NULL)
1563 			break;
1564 		bucket_free(zone, bucket, NULL);
1565 		done = true;
1566 		ZDOM_LOCK(zdom);
1567 	}
1568 	ZDOM_UNLOCK(zdom);
1569 	return (done);
1570 }
1571 
1572 static void
1573 bucket_cache_reclaim(uma_zone_t zone, bool drain, int domain)
1574 {
1575 	int i;
1576 
1577 	/*
1578 	 * Shrink the zone bucket size to ensure that the per-CPU caches
1579 	 * don't grow too large.
1580 	 */
1581 	if (zone->uz_bucket_size > zone->uz_bucket_size_min)
1582 		zone->uz_bucket_size--;
1583 
1584 	if (domain != UMA_ANYDOMAIN &&
1585 	    (zone->uz_flags & UMA_ZONE_ROUNDROBIN) == 0) {
1586 		bucket_cache_reclaim_domain(zone, drain, true, domain);
1587 	} else {
1588 		for (i = 0; i < vm_ndomains; i++)
1589 			bucket_cache_reclaim_domain(zone, drain, true, i);
1590 	}
1591 }
1592 
1593 static void
1594 keg_free_slab(uma_keg_t keg, uma_slab_t slab, int start)
1595 {
1596 	uint8_t *mem;
1597 	size_t size;
1598 	int i;
1599 	uint8_t flags;
1600 
1601 	CTR4(KTR_UMA, "keg_free_slab keg %s(%p) slab %p, returning %d bytes",
1602 	    keg->uk_name, keg, slab, PAGE_SIZE * keg->uk_ppera);
1603 
1604 	mem = slab_data(slab, keg);
1605 	size = PAGE_SIZE * keg->uk_ppera;
1606 
1607 	kasan_mark_slab_valid(keg, mem);
1608 	if (keg->uk_fini != NULL) {
1609 		for (i = start - 1; i > -1; i--)
1610 #ifdef INVARIANTS
1611 		/*
1612 		 * trash_fini implies that dtor was trash_dtor. trash_fini
1613 		 * would check that memory hasn't been modified since free,
1614 		 * which executed trash_dtor.
1615 		 * That's why we need to run uma_dbg_kskip() check here,
1616 		 * albeit we don't make skip check for other init/fini
1617 		 * invocations.
1618 		 */
1619 		if (!uma_dbg_kskip(keg, slab_item(slab, keg, i)) ||
1620 		    keg->uk_fini != trash_fini)
1621 #endif
1622 			keg->uk_fini(slab_item(slab, keg, i), keg->uk_size);
1623 	}
1624 	flags = slab->us_flags;
1625 	if (keg->uk_flags & UMA_ZFLAG_OFFPAGE) {
1626 		zone_free_item(slabzone(keg->uk_ipers), slab_tohashslab(slab),
1627 		    NULL, SKIP_NONE);
1628 	}
1629 	keg->uk_freef(mem, size, flags);
1630 	uma_total_dec(size);
1631 }
1632 
1633 static void
1634 keg_drain_domain(uma_keg_t keg, int domain)
1635 {
1636 	struct slabhead freeslabs;
1637 	uma_domain_t dom;
1638 	uma_slab_t slab, tmp;
1639 	uint32_t i, stofree, stokeep, partial;
1640 
1641 	dom = &keg->uk_domain[domain];
1642 	LIST_INIT(&freeslabs);
1643 
1644 	CTR4(KTR_UMA, "keg_drain %s(%p) domain %d free items: %u",
1645 	    keg->uk_name, keg, domain, dom->ud_free_items);
1646 
1647 	KEG_LOCK(keg, domain);
1648 
1649 	/*
1650 	 * Are the free items in partially allocated slabs sufficient to meet
1651 	 * the reserve? If not, compute the number of fully free slabs that must
1652 	 * be kept.
1653 	 */
1654 	partial = dom->ud_free_items - dom->ud_free_slabs * keg->uk_ipers;
1655 	if (partial < keg->uk_reserve) {
1656 		stokeep = min(dom->ud_free_slabs,
1657 		    howmany(keg->uk_reserve - partial, keg->uk_ipers));
1658 	} else {
1659 		stokeep = 0;
1660 	}
1661 	stofree = dom->ud_free_slabs - stokeep;
1662 
1663 	/*
1664 	 * Partition the free slabs into two sets: those that must be kept in
1665 	 * order to maintain the reserve, and those that may be released back to
1666 	 * the system.  Since one set may be much larger than the other,
1667 	 * populate the smaller of the two sets and swap them if necessary.
1668 	 */
1669 	for (i = min(stofree, stokeep); i > 0; i--) {
1670 		slab = LIST_FIRST(&dom->ud_free_slab);
1671 		LIST_REMOVE(slab, us_link);
1672 		LIST_INSERT_HEAD(&freeslabs, slab, us_link);
1673 	}
1674 	if (stofree > stokeep)
1675 		LIST_SWAP(&freeslabs, &dom->ud_free_slab, uma_slab, us_link);
1676 
1677 	if ((keg->uk_flags & UMA_ZFLAG_HASH) != 0) {
1678 		LIST_FOREACH(slab, &freeslabs, us_link)
1679 			UMA_HASH_REMOVE(&keg->uk_hash, slab);
1680 	}
1681 	dom->ud_free_items -= stofree * keg->uk_ipers;
1682 	dom->ud_free_slabs -= stofree;
1683 	dom->ud_pages -= stofree * keg->uk_ppera;
1684 	KEG_UNLOCK(keg, domain);
1685 
1686 	LIST_FOREACH_SAFE(slab, &freeslabs, us_link, tmp)
1687 		keg_free_slab(keg, slab, keg->uk_ipers);
1688 }
1689 
1690 /*
1691  * Frees pages from a keg back to the system.  This is done on demand from
1692  * the pageout daemon.
1693  *
1694  * Returns nothing.
1695  */
1696 static void
1697 keg_drain(uma_keg_t keg, int domain)
1698 {
1699 	int i;
1700 
1701 	if ((keg->uk_flags & UMA_ZONE_NOFREE) != 0)
1702 		return;
1703 	if (domain != UMA_ANYDOMAIN) {
1704 		keg_drain_domain(keg, domain);
1705 	} else {
1706 		for (i = 0; i < vm_ndomains; i++)
1707 			keg_drain_domain(keg, i);
1708 	}
1709 }
1710 
1711 static void
1712 zone_reclaim(uma_zone_t zone, int domain, int waitok, bool drain)
1713 {
1714 	/*
1715 	 * Count active reclaim operations in order to interlock with
1716 	 * zone_dtor(), which removes the zone from global lists before
1717 	 * attempting to reclaim items itself.
1718 	 *
1719 	 * The zone may be destroyed while sleeping, so only zone_dtor() should
1720 	 * specify M_WAITOK.
1721 	 */
1722 	ZONE_LOCK(zone);
1723 	if (waitok == M_WAITOK) {
1724 		while (zone->uz_reclaimers > 0)
1725 			msleep(zone, ZONE_LOCKPTR(zone), PVM, "zonedrain", 1);
1726 	}
1727 	zone->uz_reclaimers++;
1728 	ZONE_UNLOCK(zone);
1729 	bucket_cache_reclaim(zone, drain, domain);
1730 
1731 	if ((zone->uz_flags & UMA_ZFLAG_CACHE) == 0)
1732 		keg_drain(zone->uz_keg, domain);
1733 	ZONE_LOCK(zone);
1734 	zone->uz_reclaimers--;
1735 	if (zone->uz_reclaimers == 0)
1736 		wakeup(zone);
1737 	ZONE_UNLOCK(zone);
1738 }
1739 
1740 /*
1741  * Allocate a new slab for a keg and inserts it into the partial slab list.
1742  * The keg should be unlocked on entry.  If the allocation succeeds it will
1743  * be locked on return.
1744  *
1745  * Arguments:
1746  *	flags   Wait flags for the item initialization routine
1747  *	aflags  Wait flags for the slab allocation
1748  *
1749  * Returns:
1750  *	The slab that was allocated or NULL if there is no memory and the
1751  *	caller specified M_NOWAIT.
1752  */
1753 static uma_slab_t
1754 keg_alloc_slab(uma_keg_t keg, uma_zone_t zone, int domain, int flags,
1755     int aflags)
1756 {
1757 	uma_domain_t dom;
1758 	uma_slab_t slab;
1759 	unsigned long size;
1760 	uint8_t *mem;
1761 	uint8_t sflags;
1762 	int i;
1763 
1764 	KASSERT(domain >= 0 && domain < vm_ndomains,
1765 	    ("keg_alloc_slab: domain %d out of range", domain));
1766 
1767 	slab = NULL;
1768 	mem = NULL;
1769 	if (keg->uk_flags & UMA_ZFLAG_OFFPAGE) {
1770 		uma_hash_slab_t hslab;
1771 		hslab = zone_alloc_item(slabzone(keg->uk_ipers), NULL,
1772 		    domain, aflags);
1773 		if (hslab == NULL)
1774 			goto fail;
1775 		slab = &hslab->uhs_slab;
1776 	}
1777 
1778 	/*
1779 	 * This reproduces the old vm_zone behavior of zero filling pages the
1780 	 * first time they are added to a zone.
1781 	 *
1782 	 * Malloced items are zeroed in uma_zalloc.
1783 	 */
1784 
1785 	if ((keg->uk_flags & UMA_ZONE_MALLOC) == 0)
1786 		aflags |= M_ZERO;
1787 	else
1788 		aflags &= ~M_ZERO;
1789 
1790 	if (keg->uk_flags & UMA_ZONE_NODUMP)
1791 		aflags |= M_NODUMP;
1792 
1793 	/* zone is passed for legacy reasons. */
1794 	size = keg->uk_ppera * PAGE_SIZE;
1795 	mem = keg->uk_allocf(zone, size, domain, &sflags, aflags);
1796 	if (mem == NULL) {
1797 		if (keg->uk_flags & UMA_ZFLAG_OFFPAGE)
1798 			zone_free_item(slabzone(keg->uk_ipers),
1799 			    slab_tohashslab(slab), NULL, SKIP_NONE);
1800 		goto fail;
1801 	}
1802 	uma_total_inc(size);
1803 
1804 	/* For HASH zones all pages go to the same uma_domain. */
1805 	if ((keg->uk_flags & UMA_ZFLAG_HASH) != 0)
1806 		domain = 0;
1807 
1808 	/* Point the slab into the allocated memory */
1809 	if (!(keg->uk_flags & UMA_ZFLAG_OFFPAGE))
1810 		slab = (uma_slab_t)(mem + keg->uk_pgoff);
1811 	else
1812 		slab_tohashslab(slab)->uhs_data = mem;
1813 
1814 	if (keg->uk_flags & UMA_ZFLAG_VTOSLAB)
1815 		for (i = 0; i < keg->uk_ppera; i++)
1816 			vsetzoneslab((vm_offset_t)mem + (i * PAGE_SIZE),
1817 			    zone, slab);
1818 
1819 	slab->us_freecount = keg->uk_ipers;
1820 	slab->us_flags = sflags;
1821 	slab->us_domain = domain;
1822 
1823 	BIT_FILL(keg->uk_ipers, &slab->us_free);
1824 #ifdef INVARIANTS
1825 	BIT_ZERO(keg->uk_ipers, slab_dbg_bits(slab, keg));
1826 #endif
1827 
1828 	if (keg->uk_init != NULL) {
1829 		for (i = 0; i < keg->uk_ipers; i++)
1830 			if (keg->uk_init(slab_item(slab, keg, i),
1831 			    keg->uk_size, flags) != 0)
1832 				break;
1833 		if (i != keg->uk_ipers) {
1834 			keg_free_slab(keg, slab, i);
1835 			goto fail;
1836 		}
1837 	}
1838 	kasan_mark_slab_invalid(keg, mem);
1839 	KEG_LOCK(keg, domain);
1840 
1841 	CTR3(KTR_UMA, "keg_alloc_slab: allocated slab %p for %s(%p)",
1842 	    slab, keg->uk_name, keg);
1843 
1844 	if (keg->uk_flags & UMA_ZFLAG_HASH)
1845 		UMA_HASH_INSERT(&keg->uk_hash, slab, mem);
1846 
1847 	/*
1848 	 * If we got a slab here it's safe to mark it partially used
1849 	 * and return.  We assume that the caller is going to remove
1850 	 * at least one item.
1851 	 */
1852 	dom = &keg->uk_domain[domain];
1853 	LIST_INSERT_HEAD(&dom->ud_part_slab, slab, us_link);
1854 	dom->ud_pages += keg->uk_ppera;
1855 	dom->ud_free_items += keg->uk_ipers;
1856 
1857 	return (slab);
1858 
1859 fail:
1860 	return (NULL);
1861 }
1862 
1863 /*
1864  * This function is intended to be used early on in place of page_alloc().  It
1865  * performs contiguous physical memory allocations and uses a bump allocator for
1866  * KVA, so is usable before the kernel map is initialized.
1867  */
1868 static void *
1869 startup_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
1870     int wait)
1871 {
1872 	vm_paddr_t pa;
1873 	vm_page_t m;
1874 	int i, pages;
1875 
1876 	pages = howmany(bytes, PAGE_SIZE);
1877 	KASSERT(pages > 0, ("%s can't reserve 0 pages", __func__));
1878 
1879 	*pflag = UMA_SLAB_BOOT;
1880 	m = vm_page_alloc_noobj_contig_domain(domain, malloc2vm_flags(wait) |
1881 	    VM_ALLOC_WIRED, pages, (vm_paddr_t)0, ~(vm_paddr_t)0, 1, 0,
1882 	    VM_MEMATTR_DEFAULT);
1883 	if (m == NULL)
1884 		return (NULL);
1885 
1886 	pa = VM_PAGE_TO_PHYS(m);
1887 	for (i = 0; i < pages; i++, pa += PAGE_SIZE) {
1888 #if defined(__aarch64__) || defined(__amd64__) || \
1889     defined(__riscv) || defined(__powerpc64__)
1890 		if ((wait & M_NODUMP) == 0)
1891 			dump_add_page(pa);
1892 #endif
1893 	}
1894 
1895 	/* Allocate KVA and indirectly advance bootmem. */
1896 	return ((void *)pmap_map(&bootmem, m->phys_addr,
1897 	    m->phys_addr + (pages * PAGE_SIZE), VM_PROT_READ | VM_PROT_WRITE));
1898 }
1899 
1900 static void
1901 startup_free(void *mem, vm_size_t bytes)
1902 {
1903 	vm_offset_t va;
1904 	vm_page_t m;
1905 
1906 	va = (vm_offset_t)mem;
1907 	m = PHYS_TO_VM_PAGE(pmap_kextract(va));
1908 
1909 	/*
1910 	 * startup_alloc() returns direct-mapped slabs on some platforms.  Avoid
1911 	 * unmapping ranges of the direct map.
1912 	 */
1913 	if (va >= bootstart && va + bytes <= bootmem)
1914 		pmap_remove(kernel_pmap, va, va + bytes);
1915 	for (; bytes != 0; bytes -= PAGE_SIZE, m++) {
1916 #if defined(__aarch64__) || defined(__amd64__) || \
1917     defined(__riscv) || defined(__powerpc64__)
1918 		dump_drop_page(VM_PAGE_TO_PHYS(m));
1919 #endif
1920 		vm_page_unwire_noq(m);
1921 		vm_page_free(m);
1922 	}
1923 }
1924 
1925 /*
1926  * Allocates a number of pages from the system
1927  *
1928  * Arguments:
1929  *	bytes  The number of bytes requested
1930  *	wait  Shall we wait?
1931  *
1932  * Returns:
1933  *	A pointer to the alloced memory or possibly
1934  *	NULL if M_NOWAIT is set.
1935  */
1936 static void *
1937 page_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
1938     int wait)
1939 {
1940 	void *p;	/* Returned page */
1941 
1942 	*pflag = UMA_SLAB_KERNEL;
1943 	p = (void *)kmem_malloc_domainset(DOMAINSET_FIXED(domain), bytes, wait);
1944 
1945 	return (p);
1946 }
1947 
1948 static void *
1949 pcpu_page_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
1950     int wait)
1951 {
1952 	struct pglist alloctail;
1953 	vm_offset_t addr, zkva;
1954 	int cpu, flags;
1955 	vm_page_t p, p_next;
1956 #ifdef NUMA
1957 	struct pcpu *pc;
1958 #endif
1959 
1960 	MPASS(bytes == (mp_maxid + 1) * PAGE_SIZE);
1961 
1962 	TAILQ_INIT(&alloctail);
1963 	flags = VM_ALLOC_SYSTEM | VM_ALLOC_WIRED | malloc2vm_flags(wait);
1964 	*pflag = UMA_SLAB_KERNEL;
1965 	for (cpu = 0; cpu <= mp_maxid; cpu++) {
1966 		if (CPU_ABSENT(cpu)) {
1967 			p = vm_page_alloc_noobj(flags);
1968 		} else {
1969 #ifndef NUMA
1970 			p = vm_page_alloc_noobj(flags);
1971 #else
1972 			pc = pcpu_find(cpu);
1973 			if (__predict_false(VM_DOMAIN_EMPTY(pc->pc_domain)))
1974 				p = NULL;
1975 			else
1976 				p = vm_page_alloc_noobj_domain(pc->pc_domain,
1977 				    flags);
1978 			if (__predict_false(p == NULL))
1979 				p = vm_page_alloc_noobj(flags);
1980 #endif
1981 		}
1982 		if (__predict_false(p == NULL))
1983 			goto fail;
1984 		TAILQ_INSERT_TAIL(&alloctail, p, listq);
1985 	}
1986 	if ((addr = kva_alloc(bytes)) == 0)
1987 		goto fail;
1988 	zkva = addr;
1989 	TAILQ_FOREACH(p, &alloctail, listq) {
1990 		pmap_qenter(zkva, &p, 1);
1991 		zkva += PAGE_SIZE;
1992 	}
1993 	return ((void*)addr);
1994 fail:
1995 	TAILQ_FOREACH_SAFE(p, &alloctail, listq, p_next) {
1996 		vm_page_unwire_noq(p);
1997 		vm_page_free(p);
1998 	}
1999 	return (NULL);
2000 }
2001 
2002 /*
2003  * Allocates a number of pages not belonging to a VM object
2004  *
2005  * Arguments:
2006  *	bytes  The number of bytes requested
2007  *	wait   Shall we wait?
2008  *
2009  * Returns:
2010  *	A pointer to the alloced memory or possibly
2011  *	NULL if M_NOWAIT is set.
2012  */
2013 static void *
2014 noobj_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *flags,
2015     int wait)
2016 {
2017 	TAILQ_HEAD(, vm_page) alloctail;
2018 	u_long npages;
2019 	vm_offset_t retkva, zkva;
2020 	vm_page_t p, p_next;
2021 	uma_keg_t keg;
2022 	int req;
2023 
2024 	TAILQ_INIT(&alloctail);
2025 	keg = zone->uz_keg;
2026 	req = VM_ALLOC_INTERRUPT | VM_ALLOC_WIRED;
2027 	if ((wait & M_WAITOK) != 0)
2028 		req |= VM_ALLOC_WAITOK;
2029 
2030 	npages = howmany(bytes, PAGE_SIZE);
2031 	while (npages > 0) {
2032 		p = vm_page_alloc_noobj_domain(domain, req);
2033 		if (p != NULL) {
2034 			/*
2035 			 * Since the page does not belong to an object, its
2036 			 * listq is unused.
2037 			 */
2038 			TAILQ_INSERT_TAIL(&alloctail, p, listq);
2039 			npages--;
2040 			continue;
2041 		}
2042 		/*
2043 		 * Page allocation failed, free intermediate pages and
2044 		 * exit.
2045 		 */
2046 		TAILQ_FOREACH_SAFE(p, &alloctail, listq, p_next) {
2047 			vm_page_unwire_noq(p);
2048 			vm_page_free(p);
2049 		}
2050 		return (NULL);
2051 	}
2052 	*flags = UMA_SLAB_PRIV;
2053 	zkva = keg->uk_kva +
2054 	    atomic_fetchadd_long(&keg->uk_offset, round_page(bytes));
2055 	retkva = zkva;
2056 	TAILQ_FOREACH(p, &alloctail, listq) {
2057 		pmap_qenter(zkva, &p, 1);
2058 		zkva += PAGE_SIZE;
2059 	}
2060 
2061 	return ((void *)retkva);
2062 }
2063 
2064 /*
2065  * Allocate physically contiguous pages.
2066  */
2067 static void *
2068 contig_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
2069     int wait)
2070 {
2071 
2072 	*pflag = UMA_SLAB_KERNEL;
2073 	return ((void *)kmem_alloc_contig_domainset(DOMAINSET_FIXED(domain),
2074 	    bytes, wait, 0, ~(vm_paddr_t)0, 1, 0, VM_MEMATTR_DEFAULT));
2075 }
2076 
2077 /*
2078  * Frees a number of pages to the system
2079  *
2080  * Arguments:
2081  *	mem   A pointer to the memory to be freed
2082  *	size  The size of the memory being freed
2083  *	flags The original p->us_flags field
2084  *
2085  * Returns:
2086  *	Nothing
2087  */
2088 static void
2089 page_free(void *mem, vm_size_t size, uint8_t flags)
2090 {
2091 
2092 	if ((flags & UMA_SLAB_BOOT) != 0) {
2093 		startup_free(mem, size);
2094 		return;
2095 	}
2096 
2097 	KASSERT((flags & UMA_SLAB_KERNEL) != 0,
2098 	    ("UMA: page_free used with invalid flags %x", flags));
2099 
2100 	kmem_free((vm_offset_t)mem, size);
2101 }
2102 
2103 /*
2104  * Frees pcpu zone allocations
2105  *
2106  * Arguments:
2107  *	mem   A pointer to the memory to be freed
2108  *	size  The size of the memory being freed
2109  *	flags The original p->us_flags field
2110  *
2111  * Returns:
2112  *	Nothing
2113  */
2114 static void
2115 pcpu_page_free(void *mem, vm_size_t size, uint8_t flags)
2116 {
2117 	vm_offset_t sva, curva;
2118 	vm_paddr_t paddr;
2119 	vm_page_t m;
2120 
2121 	MPASS(size == (mp_maxid+1)*PAGE_SIZE);
2122 
2123 	if ((flags & UMA_SLAB_BOOT) != 0) {
2124 		startup_free(mem, size);
2125 		return;
2126 	}
2127 
2128 	sva = (vm_offset_t)mem;
2129 	for (curva = sva; curva < sva + size; curva += PAGE_SIZE) {
2130 		paddr = pmap_kextract(curva);
2131 		m = PHYS_TO_VM_PAGE(paddr);
2132 		vm_page_unwire_noq(m);
2133 		vm_page_free(m);
2134 	}
2135 	pmap_qremove(sva, size >> PAGE_SHIFT);
2136 	kva_free(sva, size);
2137 }
2138 
2139 /*
2140  * Zero fill initializer
2141  *
2142  * Arguments/Returns follow uma_init specifications
2143  */
2144 static int
2145 zero_init(void *mem, int size, int flags)
2146 {
2147 	bzero(mem, size);
2148 	return (0);
2149 }
2150 
2151 #ifdef INVARIANTS
2152 static struct noslabbits *
2153 slab_dbg_bits(uma_slab_t slab, uma_keg_t keg)
2154 {
2155 
2156 	return ((void *)((char *)&slab->us_free + BITSET_SIZE(keg->uk_ipers)));
2157 }
2158 #endif
2159 
2160 /*
2161  * Actual size of embedded struct slab (!OFFPAGE).
2162  */
2163 static size_t
2164 slab_sizeof(int nitems)
2165 {
2166 	size_t s;
2167 
2168 	s = sizeof(struct uma_slab) + BITSET_SIZE(nitems) * SLAB_BITSETS;
2169 	return (roundup(s, UMA_ALIGN_PTR + 1));
2170 }
2171 
2172 #define	UMA_FIXPT_SHIFT	31
2173 #define	UMA_FRAC_FIXPT(n, d)						\
2174 	((uint32_t)(((uint64_t)(n) << UMA_FIXPT_SHIFT) / (d)))
2175 #define	UMA_FIXPT_PCT(f)						\
2176 	((u_int)(((uint64_t)100 * (f)) >> UMA_FIXPT_SHIFT))
2177 #define	UMA_PCT_FIXPT(pct)	UMA_FRAC_FIXPT((pct), 100)
2178 #define	UMA_MIN_EFF	UMA_PCT_FIXPT(100 - UMA_MAX_WASTE)
2179 
2180 /*
2181  * Compute the number of items that will fit in a slab.  If hdr is true, the
2182  * item count may be limited to provide space in the slab for an inline slab
2183  * header.  Otherwise, all slab space will be provided for item storage.
2184  */
2185 static u_int
2186 slab_ipers_hdr(u_int size, u_int rsize, u_int slabsize, bool hdr)
2187 {
2188 	u_int ipers;
2189 	u_int padpi;
2190 
2191 	/* The padding between items is not needed after the last item. */
2192 	padpi = rsize - size;
2193 
2194 	if (hdr) {
2195 		/*
2196 		 * Start with the maximum item count and remove items until
2197 		 * the slab header first alongside the allocatable memory.
2198 		 */
2199 		for (ipers = MIN(SLAB_MAX_SETSIZE,
2200 		    (slabsize + padpi - slab_sizeof(1)) / rsize);
2201 		    ipers > 0 &&
2202 		    ipers * rsize - padpi + slab_sizeof(ipers) > slabsize;
2203 		    ipers--)
2204 			continue;
2205 	} else {
2206 		ipers = MIN((slabsize + padpi) / rsize, SLAB_MAX_SETSIZE);
2207 	}
2208 
2209 	return (ipers);
2210 }
2211 
2212 struct keg_layout_result {
2213 	u_int format;
2214 	u_int slabsize;
2215 	u_int ipers;
2216 	u_int eff;
2217 };
2218 
2219 static void
2220 keg_layout_one(uma_keg_t keg, u_int rsize, u_int slabsize, u_int fmt,
2221     struct keg_layout_result *kl)
2222 {
2223 	u_int total;
2224 
2225 	kl->format = fmt;
2226 	kl->slabsize = slabsize;
2227 
2228 	/* Handle INTERNAL as inline with an extra page. */
2229 	if ((fmt & UMA_ZFLAG_INTERNAL) != 0) {
2230 		kl->format &= ~UMA_ZFLAG_INTERNAL;
2231 		kl->slabsize += PAGE_SIZE;
2232 	}
2233 
2234 	kl->ipers = slab_ipers_hdr(keg->uk_size, rsize, kl->slabsize,
2235 	    (fmt & UMA_ZFLAG_OFFPAGE) == 0);
2236 
2237 	/* Account for memory used by an offpage slab header. */
2238 	total = kl->slabsize;
2239 	if ((fmt & UMA_ZFLAG_OFFPAGE) != 0)
2240 		total += slabzone(kl->ipers)->uz_keg->uk_rsize;
2241 
2242 	kl->eff = UMA_FRAC_FIXPT(kl->ipers * rsize, total);
2243 }
2244 
2245 /*
2246  * Determine the format of a uma keg.  This determines where the slab header
2247  * will be placed (inline or offpage) and calculates ipers, rsize, and ppera.
2248  *
2249  * Arguments
2250  *	keg  The zone we should initialize
2251  *
2252  * Returns
2253  *	Nothing
2254  */
2255 static void
2256 keg_layout(uma_keg_t keg)
2257 {
2258 	struct keg_layout_result kl = {}, kl_tmp;
2259 	u_int fmts[2];
2260 	u_int alignsize;
2261 	u_int nfmt;
2262 	u_int pages;
2263 	u_int rsize;
2264 	u_int slabsize;
2265 	u_int i, j;
2266 
2267 	KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0 ||
2268 	    (keg->uk_size <= UMA_PCPU_ALLOC_SIZE &&
2269 	     (keg->uk_flags & UMA_ZONE_CACHESPREAD) == 0),
2270 	    ("%s: cannot configure for PCPU: keg=%s, size=%u, flags=0x%b",
2271 	     __func__, keg->uk_name, keg->uk_size, keg->uk_flags,
2272 	     PRINT_UMA_ZFLAGS));
2273 	KASSERT((keg->uk_flags & (UMA_ZFLAG_INTERNAL | UMA_ZONE_VM)) == 0 ||
2274 	    (keg->uk_flags & (UMA_ZONE_NOTOUCH | UMA_ZONE_PCPU)) == 0,
2275 	    ("%s: incompatible flags 0x%b", __func__, keg->uk_flags,
2276 	     PRINT_UMA_ZFLAGS));
2277 
2278 	alignsize = keg->uk_align + 1;
2279 #ifdef KASAN
2280 	/*
2281 	 * ASAN requires that each allocation be aligned to the shadow map
2282 	 * scale factor.
2283 	 */
2284 	if (alignsize < KASAN_SHADOW_SCALE)
2285 		alignsize = KASAN_SHADOW_SCALE;
2286 #endif
2287 
2288 	/*
2289 	 * Calculate the size of each allocation (rsize) according to
2290 	 * alignment.  If the requested size is smaller than we have
2291 	 * allocation bits for we round it up.
2292 	 */
2293 	rsize = MAX(keg->uk_size, UMA_SMALLEST_UNIT);
2294 	rsize = roundup2(rsize, alignsize);
2295 
2296 	if ((keg->uk_flags & UMA_ZONE_CACHESPREAD) != 0) {
2297 		/*
2298 		 * We want one item to start on every align boundary in a page.
2299 		 * To do this we will span pages.  We will also extend the item
2300 		 * by the size of align if it is an even multiple of align.
2301 		 * Otherwise, it would fall on the same boundary every time.
2302 		 */
2303 		if ((rsize & alignsize) == 0)
2304 			rsize += alignsize;
2305 		slabsize = rsize * (PAGE_SIZE / alignsize);
2306 		slabsize = MIN(slabsize, rsize * SLAB_MAX_SETSIZE);
2307 		slabsize = MIN(slabsize, UMA_CACHESPREAD_MAX_SIZE);
2308 		slabsize = round_page(slabsize);
2309 	} else {
2310 		/*
2311 		 * Start with a slab size of as many pages as it takes to
2312 		 * represent a single item.  We will try to fit as many
2313 		 * additional items into the slab as possible.
2314 		 */
2315 		slabsize = round_page(keg->uk_size);
2316 	}
2317 
2318 	/* Build a list of all of the available formats for this keg. */
2319 	nfmt = 0;
2320 
2321 	/* Evaluate an inline slab layout. */
2322 	if ((keg->uk_flags & (UMA_ZONE_NOTOUCH | UMA_ZONE_PCPU)) == 0)
2323 		fmts[nfmt++] = 0;
2324 
2325 	/* TODO: vm_page-embedded slab. */
2326 
2327 	/*
2328 	 * We can't do OFFPAGE if we're internal or if we've been
2329 	 * asked to not go to the VM for buckets.  If we do this we
2330 	 * may end up going to the VM for slabs which we do not want
2331 	 * to do if we're UMA_ZONE_VM, which clearly forbids it.
2332 	 * In those cases, evaluate a pseudo-format called INTERNAL
2333 	 * which has an inline slab header and one extra page to
2334 	 * guarantee that it fits.
2335 	 *
2336 	 * Otherwise, see if using an OFFPAGE slab will improve our
2337 	 * efficiency.
2338 	 */
2339 	if ((keg->uk_flags & (UMA_ZFLAG_INTERNAL | UMA_ZONE_VM)) != 0)
2340 		fmts[nfmt++] = UMA_ZFLAG_INTERNAL;
2341 	else
2342 		fmts[nfmt++] = UMA_ZFLAG_OFFPAGE;
2343 
2344 	/*
2345 	 * Choose a slab size and format which satisfy the minimum efficiency.
2346 	 * Prefer the smallest slab size that meets the constraints.
2347 	 *
2348 	 * Start with a minimum slab size, to accommodate CACHESPREAD.  Then,
2349 	 * for small items (up to PAGE_SIZE), the iteration increment is one
2350 	 * page; and for large items, the increment is one item.
2351 	 */
2352 	i = (slabsize + rsize - keg->uk_size) / MAX(PAGE_SIZE, rsize);
2353 	KASSERT(i >= 1, ("keg %s(%p) flags=0x%b slabsize=%u, rsize=%u, i=%u",
2354 	    keg->uk_name, keg, keg->uk_flags, PRINT_UMA_ZFLAGS, slabsize,
2355 	    rsize, i));
2356 	for ( ; ; i++) {
2357 		slabsize = (rsize <= PAGE_SIZE) ? ptoa(i) :
2358 		    round_page(rsize * (i - 1) + keg->uk_size);
2359 
2360 		for (j = 0; j < nfmt; j++) {
2361 			/* Only if we have no viable format yet. */
2362 			if ((fmts[j] & UMA_ZFLAG_INTERNAL) != 0 &&
2363 			    kl.ipers > 0)
2364 				continue;
2365 
2366 			keg_layout_one(keg, rsize, slabsize, fmts[j], &kl_tmp);
2367 			if (kl_tmp.eff <= kl.eff)
2368 				continue;
2369 
2370 			kl = kl_tmp;
2371 
2372 			CTR6(KTR_UMA, "keg %s layout: format %#x "
2373 			    "(ipers %u * rsize %u) / slabsize %#x = %u%% eff",
2374 			    keg->uk_name, kl.format, kl.ipers, rsize,
2375 			    kl.slabsize, UMA_FIXPT_PCT(kl.eff));
2376 
2377 			/* Stop when we reach the minimum efficiency. */
2378 			if (kl.eff >= UMA_MIN_EFF)
2379 				break;
2380 		}
2381 
2382 		if (kl.eff >= UMA_MIN_EFF || !multipage_slabs ||
2383 		    slabsize >= SLAB_MAX_SETSIZE * rsize ||
2384 		    (keg->uk_flags & (UMA_ZONE_PCPU | UMA_ZONE_CONTIG)) != 0)
2385 			break;
2386 	}
2387 
2388 	pages = atop(kl.slabsize);
2389 	if ((keg->uk_flags & UMA_ZONE_PCPU) != 0)
2390 		pages *= mp_maxid + 1;
2391 
2392 	keg->uk_rsize = rsize;
2393 	keg->uk_ipers = kl.ipers;
2394 	keg->uk_ppera = pages;
2395 	keg->uk_flags |= kl.format;
2396 
2397 	/*
2398 	 * How do we find the slab header if it is offpage or if not all item
2399 	 * start addresses are in the same page?  We could solve the latter
2400 	 * case with vaddr alignment, but we don't.
2401 	 */
2402 	if ((keg->uk_flags & UMA_ZFLAG_OFFPAGE) != 0 ||
2403 	    (keg->uk_ipers - 1) * rsize >= PAGE_SIZE) {
2404 		if ((keg->uk_flags & UMA_ZONE_NOTPAGE) != 0)
2405 			keg->uk_flags |= UMA_ZFLAG_HASH;
2406 		else
2407 			keg->uk_flags |= UMA_ZFLAG_VTOSLAB;
2408 	}
2409 
2410 	CTR6(KTR_UMA, "%s: keg=%s, flags=%#x, rsize=%u, ipers=%u, ppera=%u",
2411 	    __func__, keg->uk_name, keg->uk_flags, rsize, keg->uk_ipers,
2412 	    pages);
2413 	KASSERT(keg->uk_ipers > 0 && keg->uk_ipers <= SLAB_MAX_SETSIZE,
2414 	    ("%s: keg=%s, flags=0x%b, rsize=%u, ipers=%u, ppera=%u", __func__,
2415 	     keg->uk_name, keg->uk_flags, PRINT_UMA_ZFLAGS, rsize,
2416 	     keg->uk_ipers, pages));
2417 }
2418 
2419 /*
2420  * Keg header ctor.  This initializes all fields, locks, etc.  And inserts
2421  * the keg onto the global keg list.
2422  *
2423  * Arguments/Returns follow uma_ctor specifications
2424  *	udata  Actually uma_kctor_args
2425  */
2426 static int
2427 keg_ctor(void *mem, int size, void *udata, int flags)
2428 {
2429 	struct uma_kctor_args *arg = udata;
2430 	uma_keg_t keg = mem;
2431 	uma_zone_t zone;
2432 	int i;
2433 
2434 	bzero(keg, size);
2435 	keg->uk_size = arg->size;
2436 	keg->uk_init = arg->uminit;
2437 	keg->uk_fini = arg->fini;
2438 	keg->uk_align = arg->align;
2439 	keg->uk_reserve = 0;
2440 	keg->uk_flags = arg->flags;
2441 
2442 	/*
2443 	 * We use a global round-robin policy by default.  Zones with
2444 	 * UMA_ZONE_FIRSTTOUCH set will use first-touch instead, in which
2445 	 * case the iterator is never run.
2446 	 */
2447 	keg->uk_dr.dr_policy = DOMAINSET_RR();
2448 	keg->uk_dr.dr_iter = 0;
2449 
2450 	/*
2451 	 * The primary zone is passed to us at keg-creation time.
2452 	 */
2453 	zone = arg->zone;
2454 	keg->uk_name = zone->uz_name;
2455 
2456 	if (arg->flags & UMA_ZONE_ZINIT)
2457 		keg->uk_init = zero_init;
2458 
2459 	if (arg->flags & UMA_ZONE_MALLOC)
2460 		keg->uk_flags |= UMA_ZFLAG_VTOSLAB;
2461 
2462 #ifndef SMP
2463 	keg->uk_flags &= ~UMA_ZONE_PCPU;
2464 #endif
2465 
2466 	keg_layout(keg);
2467 
2468 	/*
2469 	 * Use a first-touch NUMA policy for kegs that pmap_extract() will
2470 	 * work on.  Use round-robin for everything else.
2471 	 *
2472 	 * Zones may override the default by specifying either.
2473 	 */
2474 #ifdef NUMA
2475 	if ((keg->uk_flags &
2476 	    (UMA_ZONE_ROUNDROBIN | UMA_ZFLAG_CACHE | UMA_ZONE_NOTPAGE)) == 0)
2477 		keg->uk_flags |= UMA_ZONE_FIRSTTOUCH;
2478 	else if ((keg->uk_flags & UMA_ZONE_FIRSTTOUCH) == 0)
2479 		keg->uk_flags |= UMA_ZONE_ROUNDROBIN;
2480 #endif
2481 
2482 	/*
2483 	 * If we haven't booted yet we need allocations to go through the
2484 	 * startup cache until the vm is ready.
2485 	 */
2486 #ifdef UMA_MD_SMALL_ALLOC
2487 	if (keg->uk_ppera == 1)
2488 		keg->uk_allocf = uma_small_alloc;
2489 	else
2490 #endif
2491 	if (booted < BOOT_KVA)
2492 		keg->uk_allocf = startup_alloc;
2493 	else if (keg->uk_flags & UMA_ZONE_PCPU)
2494 		keg->uk_allocf = pcpu_page_alloc;
2495 	else if ((keg->uk_flags & UMA_ZONE_CONTIG) != 0 && keg->uk_ppera > 1)
2496 		keg->uk_allocf = contig_alloc;
2497 	else
2498 		keg->uk_allocf = page_alloc;
2499 #ifdef UMA_MD_SMALL_ALLOC
2500 	if (keg->uk_ppera == 1)
2501 		keg->uk_freef = uma_small_free;
2502 	else
2503 #endif
2504 	if (keg->uk_flags & UMA_ZONE_PCPU)
2505 		keg->uk_freef = pcpu_page_free;
2506 	else
2507 		keg->uk_freef = page_free;
2508 
2509 	/*
2510 	 * Initialize keg's locks.
2511 	 */
2512 	for (i = 0; i < vm_ndomains; i++)
2513 		KEG_LOCK_INIT(keg, i, (arg->flags & UMA_ZONE_MTXCLASS));
2514 
2515 	/*
2516 	 * If we're putting the slab header in the actual page we need to
2517 	 * figure out where in each page it goes.  See slab_sizeof
2518 	 * definition.
2519 	 */
2520 	if (!(keg->uk_flags & UMA_ZFLAG_OFFPAGE)) {
2521 		size_t shsize;
2522 
2523 		shsize = slab_sizeof(keg->uk_ipers);
2524 		keg->uk_pgoff = (PAGE_SIZE * keg->uk_ppera) - shsize;
2525 		/*
2526 		 * The only way the following is possible is if with our
2527 		 * UMA_ALIGN_PTR adjustments we are now bigger than
2528 		 * UMA_SLAB_SIZE.  I haven't checked whether this is
2529 		 * mathematically possible for all cases, so we make
2530 		 * sure here anyway.
2531 		 */
2532 		KASSERT(keg->uk_pgoff + shsize <= PAGE_SIZE * keg->uk_ppera,
2533 		    ("zone %s ipers %d rsize %d size %d slab won't fit",
2534 		    zone->uz_name, keg->uk_ipers, keg->uk_rsize, keg->uk_size));
2535 	}
2536 
2537 	if (keg->uk_flags & UMA_ZFLAG_HASH)
2538 		hash_alloc(&keg->uk_hash, 0);
2539 
2540 	CTR3(KTR_UMA, "keg_ctor %p zone %s(%p)", keg, zone->uz_name, zone);
2541 
2542 	LIST_INSERT_HEAD(&keg->uk_zones, zone, uz_link);
2543 
2544 	rw_wlock(&uma_rwlock);
2545 	LIST_INSERT_HEAD(&uma_kegs, keg, uk_link);
2546 	rw_wunlock(&uma_rwlock);
2547 	return (0);
2548 }
2549 
2550 static void
2551 zone_kva_available(uma_zone_t zone, void *unused)
2552 {
2553 	uma_keg_t keg;
2554 
2555 	if ((zone->uz_flags & UMA_ZFLAG_CACHE) != 0)
2556 		return;
2557 	KEG_GET(zone, keg);
2558 
2559 	if (keg->uk_allocf == startup_alloc) {
2560 		/* Switch to the real allocator. */
2561 		if (keg->uk_flags & UMA_ZONE_PCPU)
2562 			keg->uk_allocf = pcpu_page_alloc;
2563 		else if ((keg->uk_flags & UMA_ZONE_CONTIG) != 0 &&
2564 		    keg->uk_ppera > 1)
2565 			keg->uk_allocf = contig_alloc;
2566 		else
2567 			keg->uk_allocf = page_alloc;
2568 	}
2569 }
2570 
2571 static void
2572 zone_alloc_counters(uma_zone_t zone, void *unused)
2573 {
2574 
2575 	zone->uz_allocs = counter_u64_alloc(M_WAITOK);
2576 	zone->uz_frees = counter_u64_alloc(M_WAITOK);
2577 	zone->uz_fails = counter_u64_alloc(M_WAITOK);
2578 	zone->uz_xdomain = counter_u64_alloc(M_WAITOK);
2579 }
2580 
2581 static void
2582 zone_alloc_sysctl(uma_zone_t zone, void *unused)
2583 {
2584 	uma_zone_domain_t zdom;
2585 	uma_domain_t dom;
2586 	uma_keg_t keg;
2587 	struct sysctl_oid *oid, *domainoid;
2588 	int domains, i, cnt;
2589 	static const char *nokeg = "cache zone";
2590 	char *c;
2591 
2592 	/*
2593 	 * Make a sysctl safe copy of the zone name by removing
2594 	 * any special characters and handling dups by appending
2595 	 * an index.
2596 	 */
2597 	if (zone->uz_namecnt != 0) {
2598 		/* Count the number of decimal digits and '_' separator. */
2599 		for (i = 1, cnt = zone->uz_namecnt; cnt != 0; i++)
2600 			cnt /= 10;
2601 		zone->uz_ctlname = malloc(strlen(zone->uz_name) + i + 1,
2602 		    M_UMA, M_WAITOK);
2603 		sprintf(zone->uz_ctlname, "%s_%d", zone->uz_name,
2604 		    zone->uz_namecnt);
2605 	} else
2606 		zone->uz_ctlname = strdup(zone->uz_name, M_UMA);
2607 	for (c = zone->uz_ctlname; *c != '\0'; c++)
2608 		if (strchr("./\\ -", *c) != NULL)
2609 			*c = '_';
2610 
2611 	/*
2612 	 * Basic parameters at the root.
2613 	 */
2614 	zone->uz_oid = SYSCTL_ADD_NODE(NULL, SYSCTL_STATIC_CHILDREN(_vm_uma),
2615 	    OID_AUTO, zone->uz_ctlname, CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2616 	oid = zone->uz_oid;
2617 	SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2618 	    "size", CTLFLAG_RD, &zone->uz_size, 0, "Allocation size");
2619 	SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2620 	    "flags", CTLFLAG_RD | CTLTYPE_STRING | CTLFLAG_MPSAFE,
2621 	    zone, 0, sysctl_handle_uma_zone_flags, "A",
2622 	    "Allocator configuration flags");
2623 	SYSCTL_ADD_U16(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2624 	    "bucket_size", CTLFLAG_RD, &zone->uz_bucket_size, 0,
2625 	    "Desired per-cpu cache size");
2626 	SYSCTL_ADD_U16(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2627 	    "bucket_size_max", CTLFLAG_RD, &zone->uz_bucket_size_max, 0,
2628 	    "Maximum allowed per-cpu cache size");
2629 
2630 	/*
2631 	 * keg if present.
2632 	 */
2633 	if ((zone->uz_flags & UMA_ZFLAG_HASH) == 0)
2634 		domains = vm_ndomains;
2635 	else
2636 		domains = 1;
2637 	oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(zone->uz_oid), OID_AUTO,
2638 	    "keg", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2639 	keg = zone->uz_keg;
2640 	if ((zone->uz_flags & UMA_ZFLAG_CACHE) == 0) {
2641 		SYSCTL_ADD_CONST_STRING(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2642 		    "name", CTLFLAG_RD, keg->uk_name, "Keg name");
2643 		SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2644 		    "rsize", CTLFLAG_RD, &keg->uk_rsize, 0,
2645 		    "Real object size with alignment");
2646 		SYSCTL_ADD_U16(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2647 		    "ppera", CTLFLAG_RD, &keg->uk_ppera, 0,
2648 		    "pages per-slab allocation");
2649 		SYSCTL_ADD_U16(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2650 		    "ipers", CTLFLAG_RD, &keg->uk_ipers, 0,
2651 		    "items available per-slab");
2652 		SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2653 		    "align", CTLFLAG_RD, &keg->uk_align, 0,
2654 		    "item alignment mask");
2655 		SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2656 		    "reserve", CTLFLAG_RD, &keg->uk_reserve, 0,
2657 		    "number of reserved items");
2658 		SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2659 		    "efficiency", CTLFLAG_RD | CTLTYPE_INT | CTLFLAG_MPSAFE,
2660 		    keg, 0, sysctl_handle_uma_slab_efficiency, "I",
2661 		    "Slab utilization (100 - internal fragmentation %)");
2662 		domainoid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(oid),
2663 		    OID_AUTO, "domain", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2664 		for (i = 0; i < domains; i++) {
2665 			dom = &keg->uk_domain[i];
2666 			oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(domainoid),
2667 			    OID_AUTO, VM_DOMAIN(i)->vmd_name,
2668 			    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2669 			SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2670 			    "pages", CTLFLAG_RD, &dom->ud_pages, 0,
2671 			    "Total pages currently allocated from VM");
2672 			SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2673 			    "free_items", CTLFLAG_RD, &dom->ud_free_items, 0,
2674 			    "Items free in the slab layer");
2675 			SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2676 			    "free_slabs", CTLFLAG_RD, &dom->ud_free_slabs, 0,
2677 			    "Unused slabs");
2678 		}
2679 	} else
2680 		SYSCTL_ADD_CONST_STRING(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2681 		    "name", CTLFLAG_RD, nokeg, "Keg name");
2682 
2683 	/*
2684 	 * Information about zone limits.
2685 	 */
2686 	oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(zone->uz_oid), OID_AUTO,
2687 	    "limit", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2688 	SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2689 	    "items", CTLFLAG_RD | CTLTYPE_U64 | CTLFLAG_MPSAFE,
2690 	    zone, 0, sysctl_handle_uma_zone_items, "QU",
2691 	    "Current number of allocated items if limit is set");
2692 	SYSCTL_ADD_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2693 	    "max_items", CTLFLAG_RD, &zone->uz_max_items, 0,
2694 	    "Maximum number of allocated and cached items");
2695 	SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2696 	    "sleepers", CTLFLAG_RD, &zone->uz_sleepers, 0,
2697 	    "Number of threads sleeping at limit");
2698 	SYSCTL_ADD_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2699 	    "sleeps", CTLFLAG_RD, &zone->uz_sleeps, 0,
2700 	    "Total zone limit sleeps");
2701 	SYSCTL_ADD_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2702 	    "bucket_max", CTLFLAG_RD, &zone->uz_bucket_max, 0,
2703 	    "Maximum number of items in each domain's bucket cache");
2704 
2705 	/*
2706 	 * Per-domain zone information.
2707 	 */
2708 	domainoid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(zone->uz_oid),
2709 	    OID_AUTO, "domain", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2710 	for (i = 0; i < domains; i++) {
2711 		zdom = ZDOM_GET(zone, i);
2712 		oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(domainoid),
2713 		    OID_AUTO, VM_DOMAIN(i)->vmd_name,
2714 		    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2715 		SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2716 		    "nitems", CTLFLAG_RD, &zdom->uzd_nitems,
2717 		    "number of items in this domain");
2718 		SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2719 		    "imax", CTLFLAG_RD, &zdom->uzd_imax,
2720 		    "maximum item count in this period");
2721 		SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2722 		    "imin", CTLFLAG_RD, &zdom->uzd_imin,
2723 		    "minimum item count in this period");
2724 		SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2725 		    "bimin", CTLFLAG_RD, &zdom->uzd_bimin,
2726 		    "Minimum item count in this batch");
2727 		SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2728 		    "wss", CTLFLAG_RD, &zdom->uzd_wss,
2729 		    "Working set size");
2730 		SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2731 		    "limin", CTLFLAG_RD, &zdom->uzd_limin,
2732 		    "Long time minimum item count");
2733 		SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2734 		    "timin", CTLFLAG_RD, &zdom->uzd_timin, 0,
2735 		    "Time since zero long time minimum item count");
2736 	}
2737 
2738 	/*
2739 	 * General statistics.
2740 	 */
2741 	oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(zone->uz_oid), OID_AUTO,
2742 	    "stats", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2743 	SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2744 	    "current", CTLFLAG_RD | CTLTYPE_INT | CTLFLAG_MPSAFE,
2745 	    zone, 1, sysctl_handle_uma_zone_cur, "I",
2746 	    "Current number of allocated items");
2747 	SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2748 	    "allocs", CTLFLAG_RD | CTLTYPE_U64 | CTLFLAG_MPSAFE,
2749 	    zone, 0, sysctl_handle_uma_zone_allocs, "QU",
2750 	    "Total allocation calls");
2751 	SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2752 	    "frees", CTLFLAG_RD | CTLTYPE_U64 | CTLFLAG_MPSAFE,
2753 	    zone, 0, sysctl_handle_uma_zone_frees, "QU",
2754 	    "Total free calls");
2755 	SYSCTL_ADD_COUNTER_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2756 	    "fails", CTLFLAG_RD, &zone->uz_fails,
2757 	    "Number of allocation failures");
2758 	SYSCTL_ADD_COUNTER_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2759 	    "xdomain", CTLFLAG_RD, &zone->uz_xdomain,
2760 	    "Free calls from the wrong domain");
2761 }
2762 
2763 struct uma_zone_count {
2764 	const char	*name;
2765 	int		count;
2766 };
2767 
2768 static void
2769 zone_count(uma_zone_t zone, void *arg)
2770 {
2771 	struct uma_zone_count *cnt;
2772 
2773 	cnt = arg;
2774 	/*
2775 	 * Some zones are rapidly created with identical names and
2776 	 * destroyed out of order.  This can lead to gaps in the count.
2777 	 * Use one greater than the maximum observed for this name.
2778 	 */
2779 	if (strcmp(zone->uz_name, cnt->name) == 0)
2780 		cnt->count = MAX(cnt->count,
2781 		    zone->uz_namecnt + 1);
2782 }
2783 
2784 static void
2785 zone_update_caches(uma_zone_t zone)
2786 {
2787 	int i;
2788 
2789 	for (i = 0; i <= mp_maxid; i++) {
2790 		cache_set_uz_size(&zone->uz_cpu[i], zone->uz_size);
2791 		cache_set_uz_flags(&zone->uz_cpu[i], zone->uz_flags);
2792 	}
2793 }
2794 
2795 /*
2796  * Zone header ctor.  This initializes all fields, locks, etc.
2797  *
2798  * Arguments/Returns follow uma_ctor specifications
2799  *	udata  Actually uma_zctor_args
2800  */
2801 static int
2802 zone_ctor(void *mem, int size, void *udata, int flags)
2803 {
2804 	struct uma_zone_count cnt;
2805 	struct uma_zctor_args *arg = udata;
2806 	uma_zone_domain_t zdom;
2807 	uma_zone_t zone = mem;
2808 	uma_zone_t z;
2809 	uma_keg_t keg;
2810 	int i;
2811 
2812 	bzero(zone, size);
2813 	zone->uz_name = arg->name;
2814 	zone->uz_ctor = arg->ctor;
2815 	zone->uz_dtor = arg->dtor;
2816 	zone->uz_init = NULL;
2817 	zone->uz_fini = NULL;
2818 	zone->uz_sleeps = 0;
2819 	zone->uz_bucket_size = 0;
2820 	zone->uz_bucket_size_min = 0;
2821 	zone->uz_bucket_size_max = BUCKET_MAX;
2822 	zone->uz_flags = (arg->flags & UMA_ZONE_SMR);
2823 	zone->uz_warning = NULL;
2824 	/* The domain structures follow the cpu structures. */
2825 	zone->uz_bucket_max = ULONG_MAX;
2826 	timevalclear(&zone->uz_ratecheck);
2827 
2828 	/* Count the number of duplicate names. */
2829 	cnt.name = arg->name;
2830 	cnt.count = 0;
2831 	zone_foreach(zone_count, &cnt);
2832 	zone->uz_namecnt = cnt.count;
2833 	ZONE_CROSS_LOCK_INIT(zone);
2834 
2835 	for (i = 0; i < vm_ndomains; i++) {
2836 		zdom = ZDOM_GET(zone, i);
2837 		ZDOM_LOCK_INIT(zone, zdom, (arg->flags & UMA_ZONE_MTXCLASS));
2838 		STAILQ_INIT(&zdom->uzd_buckets);
2839 	}
2840 
2841 #if defined(INVARIANTS) && !defined(KASAN) && !defined(KMSAN)
2842 	if (arg->uminit == trash_init && arg->fini == trash_fini)
2843 		zone->uz_flags |= UMA_ZFLAG_TRASH | UMA_ZFLAG_CTORDTOR;
2844 #elif defined(KASAN)
2845 	if ((arg->flags & (UMA_ZONE_NOFREE | UMA_ZFLAG_CACHE)) != 0)
2846 		arg->flags |= UMA_ZONE_NOKASAN;
2847 #endif
2848 
2849 	/*
2850 	 * This is a pure cache zone, no kegs.
2851 	 */
2852 	if (arg->import) {
2853 		KASSERT((arg->flags & UMA_ZFLAG_CACHE) != 0,
2854 		    ("zone_ctor: Import specified for non-cache zone."));
2855 		zone->uz_flags = arg->flags;
2856 		zone->uz_size = arg->size;
2857 		zone->uz_import = arg->import;
2858 		zone->uz_release = arg->release;
2859 		zone->uz_arg = arg->arg;
2860 #ifdef NUMA
2861 		/*
2862 		 * Cache zones are round-robin unless a policy is
2863 		 * specified because they may have incompatible
2864 		 * constraints.
2865 		 */
2866 		if ((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) == 0)
2867 			zone->uz_flags |= UMA_ZONE_ROUNDROBIN;
2868 #endif
2869 		rw_wlock(&uma_rwlock);
2870 		LIST_INSERT_HEAD(&uma_cachezones, zone, uz_link);
2871 		rw_wunlock(&uma_rwlock);
2872 		goto out;
2873 	}
2874 
2875 	/*
2876 	 * Use the regular zone/keg/slab allocator.
2877 	 */
2878 	zone->uz_import = zone_import;
2879 	zone->uz_release = zone_release;
2880 	zone->uz_arg = zone;
2881 	keg = arg->keg;
2882 
2883 	if (arg->flags & UMA_ZONE_SECONDARY) {
2884 		KASSERT((zone->uz_flags & UMA_ZONE_SECONDARY) == 0,
2885 		    ("Secondary zone requested UMA_ZFLAG_INTERNAL"));
2886 		KASSERT(arg->keg != NULL, ("Secondary zone on zero'd keg"));
2887 		zone->uz_init = arg->uminit;
2888 		zone->uz_fini = arg->fini;
2889 		zone->uz_flags |= UMA_ZONE_SECONDARY;
2890 		rw_wlock(&uma_rwlock);
2891 		ZONE_LOCK(zone);
2892 		LIST_FOREACH(z, &keg->uk_zones, uz_link) {
2893 			if (LIST_NEXT(z, uz_link) == NULL) {
2894 				LIST_INSERT_AFTER(z, zone, uz_link);
2895 				break;
2896 			}
2897 		}
2898 		ZONE_UNLOCK(zone);
2899 		rw_wunlock(&uma_rwlock);
2900 	} else if (keg == NULL) {
2901 		if ((keg = uma_kcreate(zone, arg->size, arg->uminit, arg->fini,
2902 		    arg->align, arg->flags)) == NULL)
2903 			return (ENOMEM);
2904 	} else {
2905 		struct uma_kctor_args karg;
2906 		int error;
2907 
2908 		/* We should only be here from uma_startup() */
2909 		karg.size = arg->size;
2910 		karg.uminit = arg->uminit;
2911 		karg.fini = arg->fini;
2912 		karg.align = arg->align;
2913 		karg.flags = (arg->flags & ~UMA_ZONE_SMR);
2914 		karg.zone = zone;
2915 		error = keg_ctor(arg->keg, sizeof(struct uma_keg), &karg,
2916 		    flags);
2917 		if (error)
2918 			return (error);
2919 	}
2920 
2921 	/* Inherit properties from the keg. */
2922 	zone->uz_keg = keg;
2923 	zone->uz_size = keg->uk_size;
2924 	zone->uz_flags |= (keg->uk_flags &
2925 	    (UMA_ZONE_INHERIT | UMA_ZFLAG_INHERIT));
2926 
2927 out:
2928 	if (booted >= BOOT_PCPU) {
2929 		zone_alloc_counters(zone, NULL);
2930 		if (booted >= BOOT_RUNNING)
2931 			zone_alloc_sysctl(zone, NULL);
2932 	} else {
2933 		zone->uz_allocs = EARLY_COUNTER;
2934 		zone->uz_frees = EARLY_COUNTER;
2935 		zone->uz_fails = EARLY_COUNTER;
2936 	}
2937 
2938 	/* Caller requests a private SMR context. */
2939 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0)
2940 		zone->uz_smr = smr_create(zone->uz_name, 0, 0);
2941 
2942 	KASSERT((arg->flags & (UMA_ZONE_MAXBUCKET | UMA_ZONE_NOBUCKET)) !=
2943 	    (UMA_ZONE_MAXBUCKET | UMA_ZONE_NOBUCKET),
2944 	    ("Invalid zone flag combination"));
2945 	if (arg->flags & UMA_ZFLAG_INTERNAL)
2946 		zone->uz_bucket_size_max = zone->uz_bucket_size = 0;
2947 	if ((arg->flags & UMA_ZONE_MAXBUCKET) != 0)
2948 		zone->uz_bucket_size = BUCKET_MAX;
2949 	else if ((arg->flags & UMA_ZONE_NOBUCKET) != 0)
2950 		zone->uz_bucket_size = 0;
2951 	else
2952 		zone->uz_bucket_size = bucket_select(zone->uz_size);
2953 	zone->uz_bucket_size_min = zone->uz_bucket_size;
2954 	if (zone->uz_dtor != NULL || zone->uz_ctor != NULL)
2955 		zone->uz_flags |= UMA_ZFLAG_CTORDTOR;
2956 	zone_update_caches(zone);
2957 
2958 	return (0);
2959 }
2960 
2961 /*
2962  * Keg header dtor.  This frees all data, destroys locks, frees the hash
2963  * table and removes the keg from the global list.
2964  *
2965  * Arguments/Returns follow uma_dtor specifications
2966  *	udata  unused
2967  */
2968 static void
2969 keg_dtor(void *arg, int size, void *udata)
2970 {
2971 	uma_keg_t keg;
2972 	uint32_t free, pages;
2973 	int i;
2974 
2975 	keg = (uma_keg_t)arg;
2976 	free = pages = 0;
2977 	for (i = 0; i < vm_ndomains; i++) {
2978 		free += keg->uk_domain[i].ud_free_items;
2979 		pages += keg->uk_domain[i].ud_pages;
2980 		KEG_LOCK_FINI(keg, i);
2981 	}
2982 	if (pages != 0)
2983 		printf("Freed UMA keg (%s) was not empty (%u items). "
2984 		    " Lost %u pages of memory.\n",
2985 		    keg->uk_name ? keg->uk_name : "",
2986 		    pages / keg->uk_ppera * keg->uk_ipers - free, pages);
2987 
2988 	hash_free(&keg->uk_hash);
2989 }
2990 
2991 /*
2992  * Zone header dtor.
2993  *
2994  * Arguments/Returns follow uma_dtor specifications
2995  *	udata  unused
2996  */
2997 static void
2998 zone_dtor(void *arg, int size, void *udata)
2999 {
3000 	uma_zone_t zone;
3001 	uma_keg_t keg;
3002 	int i;
3003 
3004 	zone = (uma_zone_t)arg;
3005 
3006 	sysctl_remove_oid(zone->uz_oid, 1, 1);
3007 
3008 	if (!(zone->uz_flags & UMA_ZFLAG_INTERNAL))
3009 		cache_drain(zone);
3010 
3011 	rw_wlock(&uma_rwlock);
3012 	LIST_REMOVE(zone, uz_link);
3013 	rw_wunlock(&uma_rwlock);
3014 	if ((zone->uz_flags & (UMA_ZONE_SECONDARY | UMA_ZFLAG_CACHE)) == 0) {
3015 		keg = zone->uz_keg;
3016 		keg->uk_reserve = 0;
3017 	}
3018 	zone_reclaim(zone, UMA_ANYDOMAIN, M_WAITOK, true);
3019 
3020 	/*
3021 	 * We only destroy kegs from non secondary/non cache zones.
3022 	 */
3023 	if ((zone->uz_flags & (UMA_ZONE_SECONDARY | UMA_ZFLAG_CACHE)) == 0) {
3024 		keg = zone->uz_keg;
3025 		rw_wlock(&uma_rwlock);
3026 		LIST_REMOVE(keg, uk_link);
3027 		rw_wunlock(&uma_rwlock);
3028 		zone_free_item(kegs, keg, NULL, SKIP_NONE);
3029 	}
3030 	counter_u64_free(zone->uz_allocs);
3031 	counter_u64_free(zone->uz_frees);
3032 	counter_u64_free(zone->uz_fails);
3033 	counter_u64_free(zone->uz_xdomain);
3034 	free(zone->uz_ctlname, M_UMA);
3035 	for (i = 0; i < vm_ndomains; i++)
3036 		ZDOM_LOCK_FINI(ZDOM_GET(zone, i));
3037 	ZONE_CROSS_LOCK_FINI(zone);
3038 }
3039 
3040 static void
3041 zone_foreach_unlocked(void (*zfunc)(uma_zone_t, void *arg), void *arg)
3042 {
3043 	uma_keg_t keg;
3044 	uma_zone_t zone;
3045 
3046 	LIST_FOREACH(keg, &uma_kegs, uk_link) {
3047 		LIST_FOREACH(zone, &keg->uk_zones, uz_link)
3048 			zfunc(zone, arg);
3049 	}
3050 	LIST_FOREACH(zone, &uma_cachezones, uz_link)
3051 		zfunc(zone, arg);
3052 }
3053 
3054 /*
3055  * Traverses every zone in the system and calls a callback
3056  *
3057  * Arguments:
3058  *	zfunc  A pointer to a function which accepts a zone
3059  *		as an argument.
3060  *
3061  * Returns:
3062  *	Nothing
3063  */
3064 static void
3065 zone_foreach(void (*zfunc)(uma_zone_t, void *arg), void *arg)
3066 {
3067 
3068 	rw_rlock(&uma_rwlock);
3069 	zone_foreach_unlocked(zfunc, arg);
3070 	rw_runlock(&uma_rwlock);
3071 }
3072 
3073 /*
3074  * Initialize the kernel memory allocator.  This is done after pages can be
3075  * allocated but before general KVA is available.
3076  */
3077 void
3078 uma_startup1(vm_offset_t virtual_avail)
3079 {
3080 	struct uma_zctor_args args;
3081 	size_t ksize, zsize, size;
3082 	uma_keg_t primarykeg;
3083 	uintptr_t m;
3084 	int domain;
3085 	uint8_t pflag;
3086 
3087 	bootstart = bootmem = virtual_avail;
3088 
3089 	rw_init(&uma_rwlock, "UMA lock");
3090 	sx_init(&uma_reclaim_lock, "umareclaim");
3091 
3092 	ksize = sizeof(struct uma_keg) +
3093 	    (sizeof(struct uma_domain) * vm_ndomains);
3094 	ksize = roundup(ksize, UMA_SUPER_ALIGN);
3095 	zsize = sizeof(struct uma_zone) +
3096 	    (sizeof(struct uma_cache) * (mp_maxid + 1)) +
3097 	    (sizeof(struct uma_zone_domain) * vm_ndomains);
3098 	zsize = roundup(zsize, UMA_SUPER_ALIGN);
3099 
3100 	/* Allocate the zone of zones, zone of kegs, and zone of zones keg. */
3101 	size = (zsize * 2) + ksize;
3102 	for (domain = 0; domain < vm_ndomains; domain++) {
3103 		m = (uintptr_t)startup_alloc(NULL, size, domain, &pflag,
3104 		    M_NOWAIT | M_ZERO);
3105 		if (m != 0)
3106 			break;
3107 	}
3108 	zones = (uma_zone_t)m;
3109 	m += zsize;
3110 	kegs = (uma_zone_t)m;
3111 	m += zsize;
3112 	primarykeg = (uma_keg_t)m;
3113 
3114 	/* "manually" create the initial zone */
3115 	memset(&args, 0, sizeof(args));
3116 	args.name = "UMA Kegs";
3117 	args.size = ksize;
3118 	args.ctor = keg_ctor;
3119 	args.dtor = keg_dtor;
3120 	args.uminit = zero_init;
3121 	args.fini = NULL;
3122 	args.keg = primarykeg;
3123 	args.align = UMA_SUPER_ALIGN - 1;
3124 	args.flags = UMA_ZFLAG_INTERNAL;
3125 	zone_ctor(kegs, zsize, &args, M_WAITOK);
3126 
3127 	args.name = "UMA Zones";
3128 	args.size = zsize;
3129 	args.ctor = zone_ctor;
3130 	args.dtor = zone_dtor;
3131 	args.uminit = zero_init;
3132 	args.fini = NULL;
3133 	args.keg = NULL;
3134 	args.align = UMA_SUPER_ALIGN - 1;
3135 	args.flags = UMA_ZFLAG_INTERNAL;
3136 	zone_ctor(zones, zsize, &args, M_WAITOK);
3137 
3138 	/* Now make zones for slab headers */
3139 	slabzones[0] = uma_zcreate("UMA Slabs 0", SLABZONE0_SIZE,
3140 	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
3141 	slabzones[1] = uma_zcreate("UMA Slabs 1", SLABZONE1_SIZE,
3142 	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
3143 
3144 	hashzone = uma_zcreate("UMA Hash",
3145 	    sizeof(struct slabhead *) * UMA_HASH_SIZE_INIT,
3146 	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
3147 
3148 	bucket_init();
3149 	smr_init();
3150 }
3151 
3152 #ifndef UMA_MD_SMALL_ALLOC
3153 extern void vm_radix_reserve_kva(void);
3154 #endif
3155 
3156 /*
3157  * Advertise the availability of normal kva allocations and switch to
3158  * the default back-end allocator.  Marks the KVA we consumed on startup
3159  * as used in the map.
3160  */
3161 void
3162 uma_startup2(void)
3163 {
3164 
3165 	if (bootstart != bootmem) {
3166 		vm_map_lock(kernel_map);
3167 		(void)vm_map_insert(kernel_map, NULL, 0, bootstart, bootmem,
3168 		    VM_PROT_RW, VM_PROT_RW, MAP_NOFAULT);
3169 		vm_map_unlock(kernel_map);
3170 	}
3171 
3172 #ifndef UMA_MD_SMALL_ALLOC
3173 	/* Set up radix zone to use noobj_alloc. */
3174 	vm_radix_reserve_kva();
3175 #endif
3176 
3177 	booted = BOOT_KVA;
3178 	zone_foreach_unlocked(zone_kva_available, NULL);
3179 	bucket_enable();
3180 }
3181 
3182 /*
3183  * Allocate counters as early as possible so that boot-time allocations are
3184  * accounted more precisely.
3185  */
3186 static void
3187 uma_startup_pcpu(void *arg __unused)
3188 {
3189 
3190 	zone_foreach_unlocked(zone_alloc_counters, NULL);
3191 	booted = BOOT_PCPU;
3192 }
3193 SYSINIT(uma_startup_pcpu, SI_SUB_COUNTER, SI_ORDER_ANY, uma_startup_pcpu, NULL);
3194 
3195 /*
3196  * Finish our initialization steps.
3197  */
3198 static void
3199 uma_startup3(void *arg __unused)
3200 {
3201 
3202 #ifdef INVARIANTS
3203 	TUNABLE_INT_FETCH("vm.debug.divisor", &dbg_divisor);
3204 	uma_dbg_cnt = counter_u64_alloc(M_WAITOK);
3205 	uma_skip_cnt = counter_u64_alloc(M_WAITOK);
3206 #endif
3207 	zone_foreach_unlocked(zone_alloc_sysctl, NULL);
3208 	callout_init(&uma_callout, 1);
3209 	callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL);
3210 	booted = BOOT_RUNNING;
3211 
3212 	EVENTHANDLER_REGISTER(shutdown_post_sync, uma_shutdown, NULL,
3213 	    EVENTHANDLER_PRI_FIRST);
3214 }
3215 SYSINIT(uma_startup3, SI_SUB_VM_CONF, SI_ORDER_SECOND, uma_startup3, NULL);
3216 
3217 static void
3218 uma_shutdown(void)
3219 {
3220 
3221 	booted = BOOT_SHUTDOWN;
3222 }
3223 
3224 static uma_keg_t
3225 uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit, uma_fini fini,
3226 		int align, uint32_t flags)
3227 {
3228 	struct uma_kctor_args args;
3229 
3230 	args.size = size;
3231 	args.uminit = uminit;
3232 	args.fini = fini;
3233 	args.align = (align == UMA_ALIGN_CACHE) ? uma_align_cache : align;
3234 	args.flags = flags;
3235 	args.zone = zone;
3236 	return (zone_alloc_item(kegs, &args, UMA_ANYDOMAIN, M_WAITOK));
3237 }
3238 
3239 /* Public functions */
3240 /* See uma.h */
3241 void
3242 uma_set_align(int align)
3243 {
3244 
3245 	if (align != UMA_ALIGN_CACHE)
3246 		uma_align_cache = align;
3247 }
3248 
3249 /* See uma.h */
3250 uma_zone_t
3251 uma_zcreate(const char *name, size_t size, uma_ctor ctor, uma_dtor dtor,
3252 		uma_init uminit, uma_fini fini, int align, uint32_t flags)
3253 
3254 {
3255 	struct uma_zctor_args args;
3256 	uma_zone_t res;
3257 
3258 	KASSERT(powerof2(align + 1), ("invalid zone alignment %d for \"%s\"",
3259 	    align, name));
3260 
3261 	/* This stuff is essential for the zone ctor */
3262 	memset(&args, 0, sizeof(args));
3263 	args.name = name;
3264 	args.size = size;
3265 	args.ctor = ctor;
3266 	args.dtor = dtor;
3267 	args.uminit = uminit;
3268 	args.fini = fini;
3269 #if defined(INVARIANTS) && !defined(KASAN) && !defined(KMSAN)
3270 	/*
3271 	 * Inject procedures which check for memory use after free if we are
3272 	 * allowed to scramble the memory while it is not allocated.  This
3273 	 * requires that: UMA is actually able to access the memory, no init
3274 	 * or fini procedures, no dependency on the initial value of the
3275 	 * memory, and no (legitimate) use of the memory after free.  Note,
3276 	 * the ctor and dtor do not need to be empty.
3277 	 */
3278 	if ((!(flags & (UMA_ZONE_ZINIT | UMA_ZONE_NOTOUCH |
3279 	    UMA_ZONE_NOFREE))) && uminit == NULL && fini == NULL) {
3280 		args.uminit = trash_init;
3281 		args.fini = trash_fini;
3282 	}
3283 #endif
3284 	args.align = align;
3285 	args.flags = flags;
3286 	args.keg = NULL;
3287 
3288 	sx_xlock(&uma_reclaim_lock);
3289 	res = zone_alloc_item(zones, &args, UMA_ANYDOMAIN, M_WAITOK);
3290 	sx_xunlock(&uma_reclaim_lock);
3291 
3292 	return (res);
3293 }
3294 
3295 /* See uma.h */
3296 uma_zone_t
3297 uma_zsecond_create(const char *name, uma_ctor ctor, uma_dtor dtor,
3298     uma_init zinit, uma_fini zfini, uma_zone_t primary)
3299 {
3300 	struct uma_zctor_args args;
3301 	uma_keg_t keg;
3302 	uma_zone_t res;
3303 
3304 	keg = primary->uz_keg;
3305 	memset(&args, 0, sizeof(args));
3306 	args.name = name;
3307 	args.size = keg->uk_size;
3308 	args.ctor = ctor;
3309 	args.dtor = dtor;
3310 	args.uminit = zinit;
3311 	args.fini = zfini;
3312 	args.align = keg->uk_align;
3313 	args.flags = keg->uk_flags | UMA_ZONE_SECONDARY;
3314 	args.keg = keg;
3315 
3316 	sx_xlock(&uma_reclaim_lock);
3317 	res = zone_alloc_item(zones, &args, UMA_ANYDOMAIN, M_WAITOK);
3318 	sx_xunlock(&uma_reclaim_lock);
3319 
3320 	return (res);
3321 }
3322 
3323 /* See uma.h */
3324 uma_zone_t
3325 uma_zcache_create(const char *name, int size, uma_ctor ctor, uma_dtor dtor,
3326     uma_init zinit, uma_fini zfini, uma_import zimport, uma_release zrelease,
3327     void *arg, int flags)
3328 {
3329 	struct uma_zctor_args args;
3330 
3331 	memset(&args, 0, sizeof(args));
3332 	args.name = name;
3333 	args.size = size;
3334 	args.ctor = ctor;
3335 	args.dtor = dtor;
3336 	args.uminit = zinit;
3337 	args.fini = zfini;
3338 	args.import = zimport;
3339 	args.release = zrelease;
3340 	args.arg = arg;
3341 	args.align = 0;
3342 	args.flags = flags | UMA_ZFLAG_CACHE;
3343 
3344 	return (zone_alloc_item(zones, &args, UMA_ANYDOMAIN, M_WAITOK));
3345 }
3346 
3347 /* See uma.h */
3348 void
3349 uma_zdestroy(uma_zone_t zone)
3350 {
3351 
3352 	/*
3353 	 * Large slabs are expensive to reclaim, so don't bother doing
3354 	 * unnecessary work if we're shutting down.
3355 	 */
3356 	if (booted == BOOT_SHUTDOWN &&
3357 	    zone->uz_fini == NULL && zone->uz_release == zone_release)
3358 		return;
3359 	sx_xlock(&uma_reclaim_lock);
3360 	zone_free_item(zones, zone, NULL, SKIP_NONE);
3361 	sx_xunlock(&uma_reclaim_lock);
3362 }
3363 
3364 void
3365 uma_zwait(uma_zone_t zone)
3366 {
3367 
3368 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0)
3369 		uma_zfree_smr(zone, uma_zalloc_smr(zone, M_WAITOK));
3370 	else if ((zone->uz_flags & UMA_ZONE_PCPU) != 0)
3371 		uma_zfree_pcpu(zone, uma_zalloc_pcpu(zone, M_WAITOK));
3372 	else
3373 		uma_zfree(zone, uma_zalloc(zone, M_WAITOK));
3374 }
3375 
3376 void *
3377 uma_zalloc_pcpu_arg(uma_zone_t zone, void *udata, int flags)
3378 {
3379 	void *item, *pcpu_item;
3380 #ifdef SMP
3381 	int i;
3382 
3383 	MPASS(zone->uz_flags & UMA_ZONE_PCPU);
3384 #endif
3385 	item = uma_zalloc_arg(zone, udata, flags & ~M_ZERO);
3386 	if (item == NULL)
3387 		return (NULL);
3388 	pcpu_item = zpcpu_base_to_offset(item);
3389 	if (flags & M_ZERO) {
3390 #ifdef SMP
3391 		for (i = 0; i <= mp_maxid; i++)
3392 			bzero(zpcpu_get_cpu(pcpu_item, i), zone->uz_size);
3393 #else
3394 		bzero(item, zone->uz_size);
3395 #endif
3396 	}
3397 	return (pcpu_item);
3398 }
3399 
3400 /*
3401  * A stub while both regular and pcpu cases are identical.
3402  */
3403 void
3404 uma_zfree_pcpu_arg(uma_zone_t zone, void *pcpu_item, void *udata)
3405 {
3406 	void *item;
3407 
3408 #ifdef SMP
3409 	MPASS(zone->uz_flags & UMA_ZONE_PCPU);
3410 #endif
3411 
3412         /* uma_zfree_pcu_*(..., NULL) does nothing, to match free(9). */
3413         if (pcpu_item == NULL)
3414                 return;
3415 
3416 	item = zpcpu_offset_to_base(pcpu_item);
3417 	uma_zfree_arg(zone, item, udata);
3418 }
3419 
3420 static inline void *
3421 item_ctor(uma_zone_t zone, int uz_flags, int size, void *udata, int flags,
3422     void *item)
3423 {
3424 #ifdef INVARIANTS
3425 	bool skipdbg;
3426 #endif
3427 
3428 	kasan_mark_item_valid(zone, item);
3429 	kmsan_mark_item_uninitialized(zone, item);
3430 
3431 #ifdef INVARIANTS
3432 	skipdbg = uma_dbg_zskip(zone, item);
3433 	if (!skipdbg && (uz_flags & UMA_ZFLAG_TRASH) != 0 &&
3434 	    zone->uz_ctor != trash_ctor)
3435 		trash_ctor(item, size, udata, flags);
3436 #endif
3437 
3438 	/* Check flags before loading ctor pointer. */
3439 	if (__predict_false((uz_flags & UMA_ZFLAG_CTORDTOR) != 0) &&
3440 	    __predict_false(zone->uz_ctor != NULL) &&
3441 	    zone->uz_ctor(item, size, udata, flags) != 0) {
3442 		counter_u64_add(zone->uz_fails, 1);
3443 		zone_free_item(zone, item, udata, SKIP_DTOR | SKIP_CNT);
3444 		return (NULL);
3445 	}
3446 #ifdef INVARIANTS
3447 	if (!skipdbg)
3448 		uma_dbg_alloc(zone, NULL, item);
3449 #endif
3450 	if (__predict_false(flags & M_ZERO))
3451 		return (memset(item, 0, size));
3452 
3453 	return (item);
3454 }
3455 
3456 static inline void
3457 item_dtor(uma_zone_t zone, void *item, int size, void *udata,
3458     enum zfreeskip skip)
3459 {
3460 #ifdef INVARIANTS
3461 	bool skipdbg;
3462 
3463 	skipdbg = uma_dbg_zskip(zone, item);
3464 	if (skip == SKIP_NONE && !skipdbg) {
3465 		if ((zone->uz_flags & UMA_ZONE_MALLOC) != 0)
3466 			uma_dbg_free(zone, udata, item);
3467 		else
3468 			uma_dbg_free(zone, NULL, item);
3469 	}
3470 #endif
3471 	if (__predict_true(skip < SKIP_DTOR)) {
3472 		if (zone->uz_dtor != NULL)
3473 			zone->uz_dtor(item, size, udata);
3474 #ifdef INVARIANTS
3475 		if (!skipdbg && (zone->uz_flags & UMA_ZFLAG_TRASH) != 0 &&
3476 		    zone->uz_dtor != trash_dtor)
3477 			trash_dtor(item, size, udata);
3478 #endif
3479 	}
3480 	kasan_mark_item_invalid(zone, item);
3481 }
3482 
3483 #ifdef NUMA
3484 static int
3485 item_domain(void *item)
3486 {
3487 	int domain;
3488 
3489 	domain = vm_phys_domain(vtophys(item));
3490 	KASSERT(domain >= 0 && domain < vm_ndomains,
3491 	    ("%s: unknown domain for item %p", __func__, item));
3492 	return (domain);
3493 }
3494 #endif
3495 
3496 #if defined(INVARIANTS) || defined(DEBUG_MEMGUARD) || defined(WITNESS)
3497 #define	UMA_ZALLOC_DEBUG
3498 static int
3499 uma_zalloc_debug(uma_zone_t zone, void **itemp, void *udata, int flags)
3500 {
3501 	int error;
3502 
3503 	error = 0;
3504 #ifdef WITNESS
3505 	if (flags & M_WAITOK) {
3506 		WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
3507 		    "uma_zalloc_debug: zone \"%s\"", zone->uz_name);
3508 	}
3509 #endif
3510 
3511 #ifdef INVARIANTS
3512 	KASSERT((flags & M_EXEC) == 0,
3513 	    ("uma_zalloc_debug: called with M_EXEC"));
3514 	KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
3515 	    ("uma_zalloc_debug: called within spinlock or critical section"));
3516 	KASSERT((zone->uz_flags & UMA_ZONE_PCPU) == 0 || (flags & M_ZERO) == 0,
3517 	    ("uma_zalloc_debug: allocating from a pcpu zone with M_ZERO"));
3518 #endif
3519 
3520 #ifdef DEBUG_MEMGUARD
3521 	if ((zone->uz_flags & UMA_ZONE_SMR) == 0 && memguard_cmp_zone(zone)) {
3522 		void *item;
3523 		item = memguard_alloc(zone->uz_size, flags);
3524 		if (item != NULL) {
3525 			error = EJUSTRETURN;
3526 			if (zone->uz_init != NULL &&
3527 			    zone->uz_init(item, zone->uz_size, flags) != 0) {
3528 				*itemp = NULL;
3529 				return (error);
3530 			}
3531 			if (zone->uz_ctor != NULL &&
3532 			    zone->uz_ctor(item, zone->uz_size, udata,
3533 			    flags) != 0) {
3534 				counter_u64_add(zone->uz_fails, 1);
3535 				if (zone->uz_fini != NULL)
3536 					zone->uz_fini(item, zone->uz_size);
3537 				*itemp = NULL;
3538 				return (error);
3539 			}
3540 			*itemp = item;
3541 			return (error);
3542 		}
3543 		/* This is unfortunate but should not be fatal. */
3544 	}
3545 #endif
3546 	return (error);
3547 }
3548 
3549 static int
3550 uma_zfree_debug(uma_zone_t zone, void *item, void *udata)
3551 {
3552 	KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
3553 	    ("uma_zfree_debug: called with spinlock or critical section held"));
3554 
3555 #ifdef DEBUG_MEMGUARD
3556 	if ((zone->uz_flags & UMA_ZONE_SMR) == 0 && is_memguard_addr(item)) {
3557 		if (zone->uz_dtor != NULL)
3558 			zone->uz_dtor(item, zone->uz_size, udata);
3559 		if (zone->uz_fini != NULL)
3560 			zone->uz_fini(item, zone->uz_size);
3561 		memguard_free(item);
3562 		return (EJUSTRETURN);
3563 	}
3564 #endif
3565 	return (0);
3566 }
3567 #endif
3568 
3569 static inline void *
3570 cache_alloc_item(uma_zone_t zone, uma_cache_t cache, uma_cache_bucket_t bucket,
3571     void *udata, int flags)
3572 {
3573 	void *item;
3574 	int size, uz_flags;
3575 
3576 	item = cache_bucket_pop(cache, bucket);
3577 	size = cache_uz_size(cache);
3578 	uz_flags = cache_uz_flags(cache);
3579 	critical_exit();
3580 	return (item_ctor(zone, uz_flags, size, udata, flags, item));
3581 }
3582 
3583 static __noinline void *
3584 cache_alloc_retry(uma_zone_t zone, uma_cache_t cache, void *udata, int flags)
3585 {
3586 	uma_cache_bucket_t bucket;
3587 	int domain;
3588 
3589 	while (cache_alloc(zone, cache, udata, flags)) {
3590 		cache = &zone->uz_cpu[curcpu];
3591 		bucket = &cache->uc_allocbucket;
3592 		if (__predict_false(bucket->ucb_cnt == 0))
3593 			continue;
3594 		return (cache_alloc_item(zone, cache, bucket, udata, flags));
3595 	}
3596 	critical_exit();
3597 
3598 	/*
3599 	 * We can not get a bucket so try to return a single item.
3600 	 */
3601 	if (zone->uz_flags & UMA_ZONE_FIRSTTOUCH)
3602 		domain = PCPU_GET(domain);
3603 	else
3604 		domain = UMA_ANYDOMAIN;
3605 	return (zone_alloc_item(zone, udata, domain, flags));
3606 }
3607 
3608 /* See uma.h */
3609 void *
3610 uma_zalloc_smr(uma_zone_t zone, int flags)
3611 {
3612 	uma_cache_bucket_t bucket;
3613 	uma_cache_t cache;
3614 
3615 	CTR3(KTR_UMA, "uma_zalloc_smr zone %s(%p) flags %d", zone->uz_name,
3616 	    zone, flags);
3617 
3618 #ifdef UMA_ZALLOC_DEBUG
3619 	void *item;
3620 
3621 	KASSERT((zone->uz_flags & UMA_ZONE_SMR) != 0,
3622 	    ("uma_zalloc_arg: called with non-SMR zone."));
3623 	if (uma_zalloc_debug(zone, &item, NULL, flags) == EJUSTRETURN)
3624 		return (item);
3625 #endif
3626 
3627 	critical_enter();
3628 	cache = &zone->uz_cpu[curcpu];
3629 	bucket = &cache->uc_allocbucket;
3630 	if (__predict_false(bucket->ucb_cnt == 0))
3631 		return (cache_alloc_retry(zone, cache, NULL, flags));
3632 	return (cache_alloc_item(zone, cache, bucket, NULL, flags));
3633 }
3634 
3635 /* See uma.h */
3636 void *
3637 uma_zalloc_arg(uma_zone_t zone, void *udata, int flags)
3638 {
3639 	uma_cache_bucket_t bucket;
3640 	uma_cache_t cache;
3641 
3642 	/* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
3643 	random_harvest_fast_uma(&zone, sizeof(zone), RANDOM_UMA);
3644 
3645 	/* This is the fast path allocation */
3646 	CTR3(KTR_UMA, "uma_zalloc_arg zone %s(%p) flags %d", zone->uz_name,
3647 	    zone, flags);
3648 
3649 #ifdef UMA_ZALLOC_DEBUG
3650 	void *item;
3651 
3652 	KASSERT((zone->uz_flags & UMA_ZONE_SMR) == 0,
3653 	    ("uma_zalloc_arg: called with SMR zone."));
3654 	if (uma_zalloc_debug(zone, &item, udata, flags) == EJUSTRETURN)
3655 		return (item);
3656 #endif
3657 
3658 	/*
3659 	 * If possible, allocate from the per-CPU cache.  There are two
3660 	 * requirements for safe access to the per-CPU cache: (1) the thread
3661 	 * accessing the cache must not be preempted or yield during access,
3662 	 * and (2) the thread must not migrate CPUs without switching which
3663 	 * cache it accesses.  We rely on a critical section to prevent
3664 	 * preemption and migration.  We release the critical section in
3665 	 * order to acquire the zone mutex if we are unable to allocate from
3666 	 * the current cache; when we re-acquire the critical section, we
3667 	 * must detect and handle migration if it has occurred.
3668 	 */
3669 	critical_enter();
3670 	cache = &zone->uz_cpu[curcpu];
3671 	bucket = &cache->uc_allocbucket;
3672 	if (__predict_false(bucket->ucb_cnt == 0))
3673 		return (cache_alloc_retry(zone, cache, udata, flags));
3674 	return (cache_alloc_item(zone, cache, bucket, udata, flags));
3675 }
3676 
3677 /*
3678  * Replenish an alloc bucket and possibly restore an old one.  Called in
3679  * a critical section.  Returns in a critical section.
3680  *
3681  * A false return value indicates an allocation failure.
3682  * A true return value indicates success and the caller should retry.
3683  */
3684 static __noinline bool
3685 cache_alloc(uma_zone_t zone, uma_cache_t cache, void *udata, int flags)
3686 {
3687 	uma_bucket_t bucket;
3688 	int curdomain, domain;
3689 	bool new;
3690 
3691 	CRITICAL_ASSERT(curthread);
3692 
3693 	/*
3694 	 * If we have run out of items in our alloc bucket see
3695 	 * if we can switch with the free bucket.
3696 	 *
3697 	 * SMR Zones can't re-use the free bucket until the sequence has
3698 	 * expired.
3699 	 */
3700 	if ((cache_uz_flags(cache) & UMA_ZONE_SMR) == 0 &&
3701 	    cache->uc_freebucket.ucb_cnt != 0) {
3702 		cache_bucket_swap(&cache->uc_freebucket,
3703 		    &cache->uc_allocbucket);
3704 		return (true);
3705 	}
3706 
3707 	/*
3708 	 * Discard any empty allocation bucket while we hold no locks.
3709 	 */
3710 	bucket = cache_bucket_unload_alloc(cache);
3711 	critical_exit();
3712 
3713 	if (bucket != NULL) {
3714 		KASSERT(bucket->ub_cnt == 0,
3715 		    ("cache_alloc: Entered with non-empty alloc bucket."));
3716 		bucket_free(zone, bucket, udata);
3717 	}
3718 
3719 	/*
3720 	 * Attempt to retrieve the item from the per-CPU cache has failed, so
3721 	 * we must go back to the zone.  This requires the zdom lock, so we
3722 	 * must drop the critical section, then re-acquire it when we go back
3723 	 * to the cache.  Since the critical section is released, we may be
3724 	 * preempted or migrate.  As such, make sure not to maintain any
3725 	 * thread-local state specific to the cache from prior to releasing
3726 	 * the critical section.
3727 	 */
3728 	domain = PCPU_GET(domain);
3729 	if ((cache_uz_flags(cache) & UMA_ZONE_ROUNDROBIN) != 0 ||
3730 	    VM_DOMAIN_EMPTY(domain))
3731 		domain = zone_domain_highest(zone, domain);
3732 	bucket = cache_fetch_bucket(zone, cache, domain);
3733 	if (bucket == NULL && zone->uz_bucket_size != 0 && !bucketdisable) {
3734 		bucket = zone_alloc_bucket(zone, udata, domain, flags);
3735 		new = true;
3736 	} else {
3737 		new = false;
3738 	}
3739 
3740 	CTR3(KTR_UMA, "uma_zalloc: zone %s(%p) bucket zone returned %p",
3741 	    zone->uz_name, zone, bucket);
3742 	if (bucket == NULL) {
3743 		critical_enter();
3744 		return (false);
3745 	}
3746 
3747 	/*
3748 	 * See if we lost the race or were migrated.  Cache the
3749 	 * initialized bucket to make this less likely or claim
3750 	 * the memory directly.
3751 	 */
3752 	critical_enter();
3753 	cache = &zone->uz_cpu[curcpu];
3754 	if (cache->uc_allocbucket.ucb_bucket == NULL &&
3755 	    ((cache_uz_flags(cache) & UMA_ZONE_FIRSTTOUCH) == 0 ||
3756 	    (curdomain = PCPU_GET(domain)) == domain ||
3757 	    VM_DOMAIN_EMPTY(curdomain))) {
3758 		if (new)
3759 			atomic_add_long(&ZDOM_GET(zone, domain)->uzd_imax,
3760 			    bucket->ub_cnt);
3761 		cache_bucket_load_alloc(cache, bucket);
3762 		return (true);
3763 	}
3764 
3765 	/*
3766 	 * We lost the race, release this bucket and start over.
3767 	 */
3768 	critical_exit();
3769 	zone_put_bucket(zone, domain, bucket, udata, !new);
3770 	critical_enter();
3771 
3772 	return (true);
3773 }
3774 
3775 void *
3776 uma_zalloc_domain(uma_zone_t zone, void *udata, int domain, int flags)
3777 {
3778 #ifdef NUMA
3779 	uma_bucket_t bucket;
3780 	uma_zone_domain_t zdom;
3781 	void *item;
3782 #endif
3783 
3784 	/* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
3785 	random_harvest_fast_uma(&zone, sizeof(zone), RANDOM_UMA);
3786 
3787 	/* This is the fast path allocation */
3788 	CTR4(KTR_UMA, "uma_zalloc_domain zone %s(%p) domain %d flags %d",
3789 	    zone->uz_name, zone, domain, flags);
3790 
3791 	if (flags & M_WAITOK) {
3792 		WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
3793 		    "uma_zalloc_domain: zone \"%s\"", zone->uz_name);
3794 	}
3795 	KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
3796 	    ("uma_zalloc_domain: called with spinlock or critical section held"));
3797 	KASSERT((zone->uz_flags & UMA_ZONE_SMR) == 0,
3798 	    ("uma_zalloc_domain: called with SMR zone."));
3799 #ifdef NUMA
3800 	KASSERT((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) != 0,
3801 	    ("uma_zalloc_domain: called with non-FIRSTTOUCH zone."));
3802 
3803 	if (vm_ndomains == 1)
3804 		return (uma_zalloc_arg(zone, udata, flags));
3805 
3806 	/*
3807 	 * Try to allocate from the bucket cache before falling back to the keg.
3808 	 * We could try harder and attempt to allocate from per-CPU caches or
3809 	 * the per-domain cross-domain buckets, but the complexity is probably
3810 	 * not worth it.  It is more important that frees of previous
3811 	 * cross-domain allocations do not blow up the cache.
3812 	 */
3813 	zdom = zone_domain_lock(zone, domain);
3814 	if ((bucket = zone_fetch_bucket(zone, zdom, false)) != NULL) {
3815 		item = bucket->ub_bucket[bucket->ub_cnt - 1];
3816 #ifdef INVARIANTS
3817 		bucket->ub_bucket[bucket->ub_cnt - 1] = NULL;
3818 #endif
3819 		bucket->ub_cnt--;
3820 		zone_put_bucket(zone, domain, bucket, udata, true);
3821 		item = item_ctor(zone, zone->uz_flags, zone->uz_size, udata,
3822 		    flags, item);
3823 		if (item != NULL) {
3824 			KASSERT(item_domain(item) == domain,
3825 			    ("%s: bucket cache item %p from wrong domain",
3826 			    __func__, item));
3827 			counter_u64_add(zone->uz_allocs, 1);
3828 		}
3829 		return (item);
3830 	}
3831 	ZDOM_UNLOCK(zdom);
3832 	return (zone_alloc_item(zone, udata, domain, flags));
3833 #else
3834 	return (uma_zalloc_arg(zone, udata, flags));
3835 #endif
3836 }
3837 
3838 /*
3839  * Find a slab with some space.  Prefer slabs that are partially used over those
3840  * that are totally full.  This helps to reduce fragmentation.
3841  *
3842  * If 'rr' is 1, search all domains starting from 'domain'.  Otherwise check
3843  * only 'domain'.
3844  */
3845 static uma_slab_t
3846 keg_first_slab(uma_keg_t keg, int domain, bool rr)
3847 {
3848 	uma_domain_t dom;
3849 	uma_slab_t slab;
3850 	int start;
3851 
3852 	KASSERT(domain >= 0 && domain < vm_ndomains,
3853 	    ("keg_first_slab: domain %d out of range", domain));
3854 	KEG_LOCK_ASSERT(keg, domain);
3855 
3856 	slab = NULL;
3857 	start = domain;
3858 	do {
3859 		dom = &keg->uk_domain[domain];
3860 		if ((slab = LIST_FIRST(&dom->ud_part_slab)) != NULL)
3861 			return (slab);
3862 		if ((slab = LIST_FIRST(&dom->ud_free_slab)) != NULL) {
3863 			LIST_REMOVE(slab, us_link);
3864 			dom->ud_free_slabs--;
3865 			LIST_INSERT_HEAD(&dom->ud_part_slab, slab, us_link);
3866 			return (slab);
3867 		}
3868 		if (rr)
3869 			domain = (domain + 1) % vm_ndomains;
3870 	} while (domain != start);
3871 
3872 	return (NULL);
3873 }
3874 
3875 /*
3876  * Fetch an existing slab from a free or partial list.  Returns with the
3877  * keg domain lock held if a slab was found or unlocked if not.
3878  */
3879 static uma_slab_t
3880 keg_fetch_free_slab(uma_keg_t keg, int domain, bool rr, int flags)
3881 {
3882 	uma_slab_t slab;
3883 	uint32_t reserve;
3884 
3885 	/* HASH has a single free list. */
3886 	if ((keg->uk_flags & UMA_ZFLAG_HASH) != 0)
3887 		domain = 0;
3888 
3889 	KEG_LOCK(keg, domain);
3890 	reserve = (flags & M_USE_RESERVE) != 0 ? 0 : keg->uk_reserve;
3891 	if (keg->uk_domain[domain].ud_free_items <= reserve ||
3892 	    (slab = keg_first_slab(keg, domain, rr)) == NULL) {
3893 		KEG_UNLOCK(keg, domain);
3894 		return (NULL);
3895 	}
3896 	return (slab);
3897 }
3898 
3899 static uma_slab_t
3900 keg_fetch_slab(uma_keg_t keg, uma_zone_t zone, int rdomain, const int flags)
3901 {
3902 	struct vm_domainset_iter di;
3903 	uma_slab_t slab;
3904 	int aflags, domain;
3905 	bool rr;
3906 
3907 	KASSERT((flags & (M_WAITOK | M_NOVM)) != (M_WAITOK | M_NOVM),
3908 	    ("%s: invalid flags %#x", __func__, flags));
3909 
3910 restart:
3911 	/*
3912 	 * Use the keg's policy if upper layers haven't already specified a
3913 	 * domain (as happens with first-touch zones).
3914 	 *
3915 	 * To avoid races we run the iterator with the keg lock held, but that
3916 	 * means that we cannot allow the vm_domainset layer to sleep.  Thus,
3917 	 * clear M_WAITOK and handle low memory conditions locally.
3918 	 */
3919 	rr = rdomain == UMA_ANYDOMAIN;
3920 	if (rr) {
3921 		aflags = (flags & ~M_WAITOK) | M_NOWAIT;
3922 		vm_domainset_iter_policy_ref_init(&di, &keg->uk_dr, &domain,
3923 		    &aflags);
3924 	} else {
3925 		aflags = flags;
3926 		domain = rdomain;
3927 	}
3928 
3929 	for (;;) {
3930 		slab = keg_fetch_free_slab(keg, domain, rr, flags);
3931 		if (slab != NULL)
3932 			return (slab);
3933 
3934 		/*
3935 		 * M_NOVM is used to break the recursion that can otherwise
3936 		 * occur if low-level memory management routines use UMA.
3937 		 */
3938 		if ((flags & M_NOVM) == 0) {
3939 			slab = keg_alloc_slab(keg, zone, domain, flags, aflags);
3940 			if (slab != NULL)
3941 				return (slab);
3942 		}
3943 
3944 		if (!rr) {
3945 			if ((flags & M_USE_RESERVE) != 0) {
3946 				/*
3947 				 * Drain reserves from other domains before
3948 				 * giving up or sleeping.  It may be useful to
3949 				 * support per-domain reserves eventually.
3950 				 */
3951 				rdomain = UMA_ANYDOMAIN;
3952 				goto restart;
3953 			}
3954 			if ((flags & M_WAITOK) == 0)
3955 				break;
3956 			vm_wait_domain(domain);
3957 		} else if (vm_domainset_iter_policy(&di, &domain) != 0) {
3958 			if ((flags & M_WAITOK) != 0) {
3959 				vm_wait_doms(&keg->uk_dr.dr_policy->ds_mask, 0);
3960 				goto restart;
3961 			}
3962 			break;
3963 		}
3964 	}
3965 
3966 	/*
3967 	 * We might not have been able to get a slab but another cpu
3968 	 * could have while we were unlocked.  Check again before we
3969 	 * fail.
3970 	 */
3971 	if ((slab = keg_fetch_free_slab(keg, domain, rr, flags)) != NULL)
3972 		return (slab);
3973 
3974 	return (NULL);
3975 }
3976 
3977 static void *
3978 slab_alloc_item(uma_keg_t keg, uma_slab_t slab)
3979 {
3980 	uma_domain_t dom;
3981 	void *item;
3982 	int freei;
3983 
3984 	KEG_LOCK_ASSERT(keg, slab->us_domain);
3985 
3986 	dom = &keg->uk_domain[slab->us_domain];
3987 	freei = BIT_FFS(keg->uk_ipers, &slab->us_free) - 1;
3988 	BIT_CLR(keg->uk_ipers, freei, &slab->us_free);
3989 	item = slab_item(slab, keg, freei);
3990 	slab->us_freecount--;
3991 	dom->ud_free_items--;
3992 
3993 	/*
3994 	 * Move this slab to the full list.  It must be on the partial list, so
3995 	 * we do not need to update the free slab count.  In particular,
3996 	 * keg_fetch_slab() always returns slabs on the partial list.
3997 	 */
3998 	if (slab->us_freecount == 0) {
3999 		LIST_REMOVE(slab, us_link);
4000 		LIST_INSERT_HEAD(&dom->ud_full_slab, slab, us_link);
4001 	}
4002 
4003 	return (item);
4004 }
4005 
4006 static int
4007 zone_import(void *arg, void **bucket, int max, int domain, int flags)
4008 {
4009 	uma_domain_t dom;
4010 	uma_zone_t zone;
4011 	uma_slab_t slab;
4012 	uma_keg_t keg;
4013 #ifdef NUMA
4014 	int stripe;
4015 #endif
4016 	int i;
4017 
4018 	zone = arg;
4019 	slab = NULL;
4020 	keg = zone->uz_keg;
4021 	/* Try to keep the buckets totally full */
4022 	for (i = 0; i < max; ) {
4023 		if ((slab = keg_fetch_slab(keg, zone, domain, flags)) == NULL)
4024 			break;
4025 #ifdef NUMA
4026 		stripe = howmany(max, vm_ndomains);
4027 #endif
4028 		dom = &keg->uk_domain[slab->us_domain];
4029 		do {
4030 			bucket[i++] = slab_alloc_item(keg, slab);
4031 			if (keg->uk_reserve > 0 &&
4032 			    dom->ud_free_items <= keg->uk_reserve) {
4033 				/*
4034 				 * Avoid depleting the reserve after a
4035 				 * successful item allocation, even if
4036 				 * M_USE_RESERVE is specified.
4037 				 */
4038 				KEG_UNLOCK(keg, slab->us_domain);
4039 				goto out;
4040 			}
4041 #ifdef NUMA
4042 			/*
4043 			 * If the zone is striped we pick a new slab for every
4044 			 * N allocations.  Eliminating this conditional will
4045 			 * instead pick a new domain for each bucket rather
4046 			 * than stripe within each bucket.  The current option
4047 			 * produces more fragmentation and requires more cpu
4048 			 * time but yields better distribution.
4049 			 */
4050 			if ((zone->uz_flags & UMA_ZONE_ROUNDROBIN) != 0 &&
4051 			    vm_ndomains > 1 && --stripe == 0)
4052 				break;
4053 #endif
4054 		} while (slab->us_freecount != 0 && i < max);
4055 		KEG_UNLOCK(keg, slab->us_domain);
4056 
4057 		/* Don't block if we allocated any successfully. */
4058 		flags &= ~M_WAITOK;
4059 		flags |= M_NOWAIT;
4060 	}
4061 out:
4062 	return i;
4063 }
4064 
4065 static int
4066 zone_alloc_limit_hard(uma_zone_t zone, int count, int flags)
4067 {
4068 	uint64_t old, new, total, max;
4069 
4070 	/*
4071 	 * The hard case.  We're going to sleep because there were existing
4072 	 * sleepers or because we ran out of items.  This routine enforces
4073 	 * fairness by keeping fifo order.
4074 	 *
4075 	 * First release our ill gotten gains and make some noise.
4076 	 */
4077 	for (;;) {
4078 		zone_free_limit(zone, count);
4079 		zone_log_warning(zone);
4080 		zone_maxaction(zone);
4081 		if (flags & M_NOWAIT)
4082 			return (0);
4083 
4084 		/*
4085 		 * We need to allocate an item or set ourself as a sleeper
4086 		 * while the sleepq lock is held to avoid wakeup races.  This
4087 		 * is essentially a home rolled semaphore.
4088 		 */
4089 		sleepq_lock(&zone->uz_max_items);
4090 		old = zone->uz_items;
4091 		do {
4092 			MPASS(UZ_ITEMS_SLEEPERS(old) < UZ_ITEMS_SLEEPERS_MAX);
4093 			/* Cache the max since we will evaluate twice. */
4094 			max = zone->uz_max_items;
4095 			if (UZ_ITEMS_SLEEPERS(old) != 0 ||
4096 			    UZ_ITEMS_COUNT(old) >= max)
4097 				new = old + UZ_ITEMS_SLEEPER;
4098 			else
4099 				new = old + MIN(count, max - old);
4100 		} while (atomic_fcmpset_64(&zone->uz_items, &old, new) == 0);
4101 
4102 		/* We may have successfully allocated under the sleepq lock. */
4103 		if (UZ_ITEMS_SLEEPERS(new) == 0) {
4104 			sleepq_release(&zone->uz_max_items);
4105 			return (new - old);
4106 		}
4107 
4108 		/*
4109 		 * This is in a different cacheline from uz_items so that we
4110 		 * don't constantly invalidate the fastpath cacheline when we
4111 		 * adjust item counts.  This could be limited to toggling on
4112 		 * transitions.
4113 		 */
4114 		atomic_add_32(&zone->uz_sleepers, 1);
4115 		atomic_add_64(&zone->uz_sleeps, 1);
4116 
4117 		/*
4118 		 * We have added ourselves as a sleeper.  The sleepq lock
4119 		 * protects us from wakeup races.  Sleep now and then retry.
4120 		 */
4121 		sleepq_add(&zone->uz_max_items, NULL, "zonelimit", 0, 0);
4122 		sleepq_wait(&zone->uz_max_items, PVM);
4123 
4124 		/*
4125 		 * After wakeup, remove ourselves as a sleeper and try
4126 		 * again.  We no longer have the sleepq lock for protection.
4127 		 *
4128 		 * Subract ourselves as a sleeper while attempting to add
4129 		 * our count.
4130 		 */
4131 		atomic_subtract_32(&zone->uz_sleepers, 1);
4132 		old = atomic_fetchadd_64(&zone->uz_items,
4133 		    -(UZ_ITEMS_SLEEPER - count));
4134 		/* We're no longer a sleeper. */
4135 		old -= UZ_ITEMS_SLEEPER;
4136 
4137 		/*
4138 		 * If we're still at the limit, restart.  Notably do not
4139 		 * block on other sleepers.  Cache the max value to protect
4140 		 * against changes via sysctl.
4141 		 */
4142 		total = UZ_ITEMS_COUNT(old);
4143 		max = zone->uz_max_items;
4144 		if (total >= max)
4145 			continue;
4146 		/* Truncate if necessary, otherwise wake other sleepers. */
4147 		if (total + count > max) {
4148 			zone_free_limit(zone, total + count - max);
4149 			count = max - total;
4150 		} else if (total + count < max && UZ_ITEMS_SLEEPERS(old) != 0)
4151 			wakeup_one(&zone->uz_max_items);
4152 
4153 		return (count);
4154 	}
4155 }
4156 
4157 /*
4158  * Allocate 'count' items from our max_items limit.  Returns the number
4159  * available.  If M_NOWAIT is not specified it will sleep until at least
4160  * one item can be allocated.
4161  */
4162 static int
4163 zone_alloc_limit(uma_zone_t zone, int count, int flags)
4164 {
4165 	uint64_t old;
4166 	uint64_t max;
4167 
4168 	max = zone->uz_max_items;
4169 	MPASS(max > 0);
4170 
4171 	/*
4172 	 * We expect normal allocations to succeed with a simple
4173 	 * fetchadd.
4174 	 */
4175 	old = atomic_fetchadd_64(&zone->uz_items, count);
4176 	if (__predict_true(old + count <= max))
4177 		return (count);
4178 
4179 	/*
4180 	 * If we had some items and no sleepers just return the
4181 	 * truncated value.  We have to release the excess space
4182 	 * though because that may wake sleepers who weren't woken
4183 	 * because we were temporarily over the limit.
4184 	 */
4185 	if (old < max) {
4186 		zone_free_limit(zone, (old + count) - max);
4187 		return (max - old);
4188 	}
4189 	return (zone_alloc_limit_hard(zone, count, flags));
4190 }
4191 
4192 /*
4193  * Free a number of items back to the limit.
4194  */
4195 static void
4196 zone_free_limit(uma_zone_t zone, int count)
4197 {
4198 	uint64_t old;
4199 
4200 	MPASS(count > 0);
4201 
4202 	/*
4203 	 * In the common case we either have no sleepers or
4204 	 * are still over the limit and can just return.
4205 	 */
4206 	old = atomic_fetchadd_64(&zone->uz_items, -count);
4207 	if (__predict_true(UZ_ITEMS_SLEEPERS(old) == 0 ||
4208 	   UZ_ITEMS_COUNT(old) - count >= zone->uz_max_items))
4209 		return;
4210 
4211 	/*
4212 	 * Moderate the rate of wakeups.  Sleepers will continue
4213 	 * to generate wakeups if necessary.
4214 	 */
4215 	wakeup_one(&zone->uz_max_items);
4216 }
4217 
4218 static uma_bucket_t
4219 zone_alloc_bucket(uma_zone_t zone, void *udata, int domain, int flags)
4220 {
4221 	uma_bucket_t bucket;
4222 	int error, maxbucket, cnt;
4223 
4224 	CTR3(KTR_UMA, "zone_alloc_bucket zone %s(%p) domain %d", zone->uz_name,
4225 	    zone, domain);
4226 
4227 	/* Avoid allocs targeting empty domains. */
4228 	if (domain != UMA_ANYDOMAIN && VM_DOMAIN_EMPTY(domain))
4229 		domain = UMA_ANYDOMAIN;
4230 	else if ((zone->uz_flags & UMA_ZONE_ROUNDROBIN) != 0)
4231 		domain = UMA_ANYDOMAIN;
4232 
4233 	if (zone->uz_max_items > 0)
4234 		maxbucket = zone_alloc_limit(zone, zone->uz_bucket_size,
4235 		    M_NOWAIT);
4236 	else
4237 		maxbucket = zone->uz_bucket_size;
4238 	if (maxbucket == 0)
4239 		return (false);
4240 
4241 	/* Don't wait for buckets, preserve caller's NOVM setting. */
4242 	bucket = bucket_alloc(zone, udata, M_NOWAIT | (flags & M_NOVM));
4243 	if (bucket == NULL) {
4244 		cnt = 0;
4245 		goto out;
4246 	}
4247 
4248 	bucket->ub_cnt = zone->uz_import(zone->uz_arg, bucket->ub_bucket,
4249 	    MIN(maxbucket, bucket->ub_entries), domain, flags);
4250 
4251 	/*
4252 	 * Initialize the memory if necessary.
4253 	 */
4254 	if (bucket->ub_cnt != 0 && zone->uz_init != NULL) {
4255 		int i;
4256 
4257 		for (i = 0; i < bucket->ub_cnt; i++) {
4258 			kasan_mark_item_valid(zone, bucket->ub_bucket[i]);
4259 			error = zone->uz_init(bucket->ub_bucket[i],
4260 			    zone->uz_size, flags);
4261 			kasan_mark_item_invalid(zone, bucket->ub_bucket[i]);
4262 			if (error != 0)
4263 				break;
4264 		}
4265 
4266 		/*
4267 		 * If we couldn't initialize the whole bucket, put the
4268 		 * rest back onto the freelist.
4269 		 */
4270 		if (i != bucket->ub_cnt) {
4271 			zone->uz_release(zone->uz_arg, &bucket->ub_bucket[i],
4272 			    bucket->ub_cnt - i);
4273 #ifdef INVARIANTS
4274 			bzero(&bucket->ub_bucket[i],
4275 			    sizeof(void *) * (bucket->ub_cnt - i));
4276 #endif
4277 			bucket->ub_cnt = i;
4278 		}
4279 	}
4280 
4281 	cnt = bucket->ub_cnt;
4282 	if (bucket->ub_cnt == 0) {
4283 		bucket_free(zone, bucket, udata);
4284 		counter_u64_add(zone->uz_fails, 1);
4285 		bucket = NULL;
4286 	}
4287 out:
4288 	if (zone->uz_max_items > 0 && cnt < maxbucket)
4289 		zone_free_limit(zone, maxbucket - cnt);
4290 
4291 	return (bucket);
4292 }
4293 
4294 /*
4295  * Allocates a single item from a zone.
4296  *
4297  * Arguments
4298  *	zone   The zone to alloc for.
4299  *	udata  The data to be passed to the constructor.
4300  *	domain The domain to allocate from or UMA_ANYDOMAIN.
4301  *	flags  M_WAITOK, M_NOWAIT, M_ZERO.
4302  *
4303  * Returns
4304  *	NULL if there is no memory and M_NOWAIT is set
4305  *	An item if successful
4306  */
4307 
4308 static void *
4309 zone_alloc_item(uma_zone_t zone, void *udata, int domain, int flags)
4310 {
4311 	void *item;
4312 
4313 	if (zone->uz_max_items > 0 && zone_alloc_limit(zone, 1, flags) == 0) {
4314 		counter_u64_add(zone->uz_fails, 1);
4315 		return (NULL);
4316 	}
4317 
4318 	/* Avoid allocs targeting empty domains. */
4319 	if (domain != UMA_ANYDOMAIN && VM_DOMAIN_EMPTY(domain))
4320 		domain = UMA_ANYDOMAIN;
4321 
4322 	if (zone->uz_import(zone->uz_arg, &item, 1, domain, flags) != 1)
4323 		goto fail_cnt;
4324 
4325 	/*
4326 	 * We have to call both the zone's init (not the keg's init)
4327 	 * and the zone's ctor.  This is because the item is going from
4328 	 * a keg slab directly to the user, and the user is expecting it
4329 	 * to be both zone-init'd as well as zone-ctor'd.
4330 	 */
4331 	if (zone->uz_init != NULL) {
4332 		int error;
4333 
4334 		kasan_mark_item_valid(zone, item);
4335 		error = zone->uz_init(item, zone->uz_size, flags);
4336 		kasan_mark_item_invalid(zone, item);
4337 		if (error != 0) {
4338 			zone_free_item(zone, item, udata, SKIP_FINI | SKIP_CNT);
4339 			goto fail_cnt;
4340 		}
4341 	}
4342 	item = item_ctor(zone, zone->uz_flags, zone->uz_size, udata, flags,
4343 	    item);
4344 	if (item == NULL)
4345 		goto fail;
4346 
4347 	counter_u64_add(zone->uz_allocs, 1);
4348 	CTR3(KTR_UMA, "zone_alloc_item item %p from %s(%p)", item,
4349 	    zone->uz_name, zone);
4350 
4351 	return (item);
4352 
4353 fail_cnt:
4354 	counter_u64_add(zone->uz_fails, 1);
4355 fail:
4356 	if (zone->uz_max_items > 0)
4357 		zone_free_limit(zone, 1);
4358 	CTR2(KTR_UMA, "zone_alloc_item failed from %s(%p)",
4359 	    zone->uz_name, zone);
4360 
4361 	return (NULL);
4362 }
4363 
4364 /* See uma.h */
4365 void
4366 uma_zfree_smr(uma_zone_t zone, void *item)
4367 {
4368 	uma_cache_t cache;
4369 	uma_cache_bucket_t bucket;
4370 	int itemdomain, uz_flags;
4371 
4372 	CTR3(KTR_UMA, "uma_zfree_smr zone %s(%p) item %p",
4373 	    zone->uz_name, zone, item);
4374 
4375 #ifdef UMA_ZALLOC_DEBUG
4376 	KASSERT((zone->uz_flags & UMA_ZONE_SMR) != 0,
4377 	    ("uma_zfree_smr: called with non-SMR zone."));
4378 	KASSERT(item != NULL, ("uma_zfree_smr: Called with NULL pointer."));
4379 	SMR_ASSERT_NOT_ENTERED(zone->uz_smr);
4380 	if (uma_zfree_debug(zone, item, NULL) == EJUSTRETURN)
4381 		return;
4382 #endif
4383 	cache = &zone->uz_cpu[curcpu];
4384 	uz_flags = cache_uz_flags(cache);
4385 	itemdomain = 0;
4386 #ifdef NUMA
4387 	if ((uz_flags & UMA_ZONE_FIRSTTOUCH) != 0)
4388 		itemdomain = item_domain(item);
4389 #endif
4390 	critical_enter();
4391 	do {
4392 		cache = &zone->uz_cpu[curcpu];
4393 		/* SMR Zones must free to the free bucket. */
4394 		bucket = &cache->uc_freebucket;
4395 #ifdef NUMA
4396 		if ((uz_flags & UMA_ZONE_FIRSTTOUCH) != 0 &&
4397 		    PCPU_GET(domain) != itemdomain) {
4398 			bucket = &cache->uc_crossbucket;
4399 		}
4400 #endif
4401 		if (__predict_true(bucket->ucb_cnt < bucket->ucb_entries)) {
4402 			cache_bucket_push(cache, bucket, item);
4403 			critical_exit();
4404 			return;
4405 		}
4406 	} while (cache_free(zone, cache, NULL, itemdomain));
4407 	critical_exit();
4408 
4409 	/*
4410 	 * If nothing else caught this, we'll just do an internal free.
4411 	 */
4412 	zone_free_item(zone, item, NULL, SKIP_NONE);
4413 }
4414 
4415 /* See uma.h */
4416 void
4417 uma_zfree_arg(uma_zone_t zone, void *item, void *udata)
4418 {
4419 	uma_cache_t cache;
4420 	uma_cache_bucket_t bucket;
4421 	int itemdomain, uz_flags;
4422 
4423 	/* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
4424 	random_harvest_fast_uma(&zone, sizeof(zone), RANDOM_UMA);
4425 
4426 	CTR3(KTR_UMA, "uma_zfree_arg zone %s(%p) item %p",
4427 	    zone->uz_name, zone, item);
4428 
4429 #ifdef UMA_ZALLOC_DEBUG
4430 	KASSERT((zone->uz_flags & UMA_ZONE_SMR) == 0,
4431 	    ("uma_zfree_arg: called with SMR zone."));
4432 	if (uma_zfree_debug(zone, item, udata) == EJUSTRETURN)
4433 		return;
4434 #endif
4435         /* uma_zfree(..., NULL) does nothing, to match free(9). */
4436         if (item == NULL)
4437                 return;
4438 
4439 	/*
4440 	 * We are accessing the per-cpu cache without a critical section to
4441 	 * fetch size and flags.  This is acceptable, if we are preempted we
4442 	 * will simply read another cpu's line.
4443 	 */
4444 	cache = &zone->uz_cpu[curcpu];
4445 	uz_flags = cache_uz_flags(cache);
4446 	if (UMA_ALWAYS_CTORDTOR ||
4447 	    __predict_false((uz_flags & UMA_ZFLAG_CTORDTOR) != 0))
4448 		item_dtor(zone, item, cache_uz_size(cache), udata, SKIP_NONE);
4449 
4450 	/*
4451 	 * The race here is acceptable.  If we miss it we'll just have to wait
4452 	 * a little longer for the limits to be reset.
4453 	 */
4454 	if (__predict_false(uz_flags & UMA_ZFLAG_LIMIT)) {
4455 		if (atomic_load_32(&zone->uz_sleepers) > 0)
4456 			goto zfree_item;
4457 	}
4458 
4459 	/*
4460 	 * If possible, free to the per-CPU cache.  There are two
4461 	 * requirements for safe access to the per-CPU cache: (1) the thread
4462 	 * accessing the cache must not be preempted or yield during access,
4463 	 * and (2) the thread must not migrate CPUs without switching which
4464 	 * cache it accesses.  We rely on a critical section to prevent
4465 	 * preemption and migration.  We release the critical section in
4466 	 * order to acquire the zone mutex if we are unable to free to the
4467 	 * current cache; when we re-acquire the critical section, we must
4468 	 * detect and handle migration if it has occurred.
4469 	 */
4470 	itemdomain = 0;
4471 #ifdef NUMA
4472 	if ((uz_flags & UMA_ZONE_FIRSTTOUCH) != 0)
4473 		itemdomain = item_domain(item);
4474 #endif
4475 	critical_enter();
4476 	do {
4477 		cache = &zone->uz_cpu[curcpu];
4478 		/*
4479 		 * Try to free into the allocbucket first to give LIFO
4480 		 * ordering for cache-hot datastructures.  Spill over
4481 		 * into the freebucket if necessary.  Alloc will swap
4482 		 * them if one runs dry.
4483 		 */
4484 		bucket = &cache->uc_allocbucket;
4485 #ifdef NUMA
4486 		if ((uz_flags & UMA_ZONE_FIRSTTOUCH) != 0 &&
4487 		    PCPU_GET(domain) != itemdomain) {
4488 			bucket = &cache->uc_crossbucket;
4489 		} else
4490 #endif
4491 		if (bucket->ucb_cnt == bucket->ucb_entries &&
4492 		   cache->uc_freebucket.ucb_cnt <
4493 		   cache->uc_freebucket.ucb_entries)
4494 			cache_bucket_swap(&cache->uc_freebucket,
4495 			    &cache->uc_allocbucket);
4496 		if (__predict_true(bucket->ucb_cnt < bucket->ucb_entries)) {
4497 			cache_bucket_push(cache, bucket, item);
4498 			critical_exit();
4499 			return;
4500 		}
4501 	} while (cache_free(zone, cache, udata, itemdomain));
4502 	critical_exit();
4503 
4504 	/*
4505 	 * If nothing else caught this, we'll just do an internal free.
4506 	 */
4507 zfree_item:
4508 	zone_free_item(zone, item, udata, SKIP_DTOR);
4509 }
4510 
4511 #ifdef NUMA
4512 /*
4513  * sort crossdomain free buckets to domain correct buckets and cache
4514  * them.
4515  */
4516 static void
4517 zone_free_cross(uma_zone_t zone, uma_bucket_t bucket, void *udata)
4518 {
4519 	struct uma_bucketlist emptybuckets, fullbuckets;
4520 	uma_zone_domain_t zdom;
4521 	uma_bucket_t b;
4522 	smr_seq_t seq;
4523 	void *item;
4524 	int domain;
4525 
4526 	CTR3(KTR_UMA,
4527 	    "uma_zfree: zone %s(%p) draining cross bucket %p",
4528 	    zone->uz_name, zone, bucket);
4529 
4530 	/*
4531 	 * It is possible for buckets to arrive here out of order so we fetch
4532 	 * the current smr seq rather than accepting the bucket's.
4533 	 */
4534 	seq = SMR_SEQ_INVALID;
4535 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0)
4536 		seq = smr_advance(zone->uz_smr);
4537 
4538 	/*
4539 	 * To avoid having ndomain * ndomain buckets for sorting we have a
4540 	 * lock on the current crossfree bucket.  A full matrix with
4541 	 * per-domain locking could be used if necessary.
4542 	 */
4543 	STAILQ_INIT(&emptybuckets);
4544 	STAILQ_INIT(&fullbuckets);
4545 	ZONE_CROSS_LOCK(zone);
4546 	for (; bucket->ub_cnt > 0; bucket->ub_cnt--) {
4547 		item = bucket->ub_bucket[bucket->ub_cnt - 1];
4548 		domain = item_domain(item);
4549 		zdom = ZDOM_GET(zone, domain);
4550 		if (zdom->uzd_cross == NULL) {
4551 			if ((b = STAILQ_FIRST(&emptybuckets)) != NULL) {
4552 				STAILQ_REMOVE_HEAD(&emptybuckets, ub_link);
4553 				zdom->uzd_cross = b;
4554 			} else {
4555 				/*
4556 				 * Avoid allocating a bucket with the cross lock
4557 				 * held, since allocation can trigger a
4558 				 * cross-domain free and bucket zones may
4559 				 * allocate from each other.
4560 				 */
4561 				ZONE_CROSS_UNLOCK(zone);
4562 				b = bucket_alloc(zone, udata, M_NOWAIT);
4563 				if (b == NULL)
4564 					goto out;
4565 				ZONE_CROSS_LOCK(zone);
4566 				if (zdom->uzd_cross != NULL) {
4567 					STAILQ_INSERT_HEAD(&emptybuckets, b,
4568 					    ub_link);
4569 				} else {
4570 					zdom->uzd_cross = b;
4571 				}
4572 			}
4573 		}
4574 		b = zdom->uzd_cross;
4575 		b->ub_bucket[b->ub_cnt++] = item;
4576 		b->ub_seq = seq;
4577 		if (b->ub_cnt == b->ub_entries) {
4578 			STAILQ_INSERT_HEAD(&fullbuckets, b, ub_link);
4579 			if ((b = STAILQ_FIRST(&emptybuckets)) != NULL)
4580 				STAILQ_REMOVE_HEAD(&emptybuckets, ub_link);
4581 			zdom->uzd_cross = b;
4582 		}
4583 	}
4584 	ZONE_CROSS_UNLOCK(zone);
4585 out:
4586 	if (bucket->ub_cnt == 0)
4587 		bucket->ub_seq = SMR_SEQ_INVALID;
4588 	bucket_free(zone, bucket, udata);
4589 
4590 	while ((b = STAILQ_FIRST(&emptybuckets)) != NULL) {
4591 		STAILQ_REMOVE_HEAD(&emptybuckets, ub_link);
4592 		bucket_free(zone, b, udata);
4593 	}
4594 	while ((b = STAILQ_FIRST(&fullbuckets)) != NULL) {
4595 		STAILQ_REMOVE_HEAD(&fullbuckets, ub_link);
4596 		domain = item_domain(b->ub_bucket[0]);
4597 		zone_put_bucket(zone, domain, b, udata, true);
4598 	}
4599 }
4600 #endif
4601 
4602 static void
4603 zone_free_bucket(uma_zone_t zone, uma_bucket_t bucket, void *udata,
4604     int itemdomain, bool ws)
4605 {
4606 
4607 #ifdef NUMA
4608 	/*
4609 	 * Buckets coming from the wrong domain will be entirely for the
4610 	 * only other domain on two domain systems.  In this case we can
4611 	 * simply cache them.  Otherwise we need to sort them back to
4612 	 * correct domains.
4613 	 */
4614 	if ((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) != 0 &&
4615 	    vm_ndomains > 2 && PCPU_GET(domain) != itemdomain) {
4616 		zone_free_cross(zone, bucket, udata);
4617 		return;
4618 	}
4619 #endif
4620 
4621 	/*
4622 	 * Attempt to save the bucket in the zone's domain bucket cache.
4623 	 */
4624 	CTR3(KTR_UMA,
4625 	    "uma_zfree: zone %s(%p) putting bucket %p on free list",
4626 	    zone->uz_name, zone, bucket);
4627 	/* ub_cnt is pointing to the last free item */
4628 	if ((zone->uz_flags & UMA_ZONE_ROUNDROBIN) != 0)
4629 		itemdomain = zone_domain_lowest(zone, itemdomain);
4630 	zone_put_bucket(zone, itemdomain, bucket, udata, ws);
4631 }
4632 
4633 /*
4634  * Populate a free or cross bucket for the current cpu cache.  Free any
4635  * existing full bucket either to the zone cache or back to the slab layer.
4636  *
4637  * Enters and returns in a critical section.  false return indicates that
4638  * we can not satisfy this free in the cache layer.  true indicates that
4639  * the caller should retry.
4640  */
4641 static __noinline bool
4642 cache_free(uma_zone_t zone, uma_cache_t cache, void *udata, int itemdomain)
4643 {
4644 	uma_cache_bucket_t cbucket;
4645 	uma_bucket_t newbucket, bucket;
4646 
4647 	CRITICAL_ASSERT(curthread);
4648 
4649 	if (zone->uz_bucket_size == 0)
4650 		return false;
4651 
4652 	cache = &zone->uz_cpu[curcpu];
4653 	newbucket = NULL;
4654 
4655 	/*
4656 	 * FIRSTTOUCH domains need to free to the correct zdom.  When
4657 	 * enabled this is the zdom of the item.   The bucket is the
4658 	 * cross bucket if the current domain and itemdomain do not match.
4659 	 */
4660 	cbucket = &cache->uc_freebucket;
4661 #ifdef NUMA
4662 	if ((cache_uz_flags(cache) & UMA_ZONE_FIRSTTOUCH) != 0) {
4663 		if (PCPU_GET(domain) != itemdomain) {
4664 			cbucket = &cache->uc_crossbucket;
4665 			if (cbucket->ucb_cnt != 0)
4666 				counter_u64_add(zone->uz_xdomain,
4667 				    cbucket->ucb_cnt);
4668 		}
4669 	}
4670 #endif
4671 	bucket = cache_bucket_unload(cbucket);
4672 	KASSERT(bucket == NULL || bucket->ub_cnt == bucket->ub_entries,
4673 	    ("cache_free: Entered with non-full free bucket."));
4674 
4675 	/* We are no longer associated with this CPU. */
4676 	critical_exit();
4677 
4678 	/*
4679 	 * Don't let SMR zones operate without a free bucket.  Force
4680 	 * a synchronize and re-use this one.  We will only degrade
4681 	 * to a synchronize every bucket_size items rather than every
4682 	 * item if we fail to allocate a bucket.
4683 	 */
4684 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0) {
4685 		if (bucket != NULL)
4686 			bucket->ub_seq = smr_advance(zone->uz_smr);
4687 		newbucket = bucket_alloc(zone, udata, M_NOWAIT);
4688 		if (newbucket == NULL && bucket != NULL) {
4689 			bucket_drain(zone, bucket);
4690 			newbucket = bucket;
4691 			bucket = NULL;
4692 		}
4693 	} else if (!bucketdisable)
4694 		newbucket = bucket_alloc(zone, udata, M_NOWAIT);
4695 
4696 	if (bucket != NULL)
4697 		zone_free_bucket(zone, bucket, udata, itemdomain, true);
4698 
4699 	critical_enter();
4700 	if ((bucket = newbucket) == NULL)
4701 		return (false);
4702 	cache = &zone->uz_cpu[curcpu];
4703 #ifdef NUMA
4704 	/*
4705 	 * Check to see if we should be populating the cross bucket.  If it
4706 	 * is already populated we will fall through and attempt to populate
4707 	 * the free bucket.
4708 	 */
4709 	if ((cache_uz_flags(cache) & UMA_ZONE_FIRSTTOUCH) != 0) {
4710 		if (PCPU_GET(domain) != itemdomain &&
4711 		    cache->uc_crossbucket.ucb_bucket == NULL) {
4712 			cache_bucket_load_cross(cache, bucket);
4713 			return (true);
4714 		}
4715 	}
4716 #endif
4717 	/*
4718 	 * We may have lost the race to fill the bucket or switched CPUs.
4719 	 */
4720 	if (cache->uc_freebucket.ucb_bucket != NULL) {
4721 		critical_exit();
4722 		bucket_free(zone, bucket, udata);
4723 		critical_enter();
4724 	} else
4725 		cache_bucket_load_free(cache, bucket);
4726 
4727 	return (true);
4728 }
4729 
4730 static void
4731 slab_free_item(uma_zone_t zone, uma_slab_t slab, void *item)
4732 {
4733 	uma_keg_t keg;
4734 	uma_domain_t dom;
4735 	int freei;
4736 
4737 	keg = zone->uz_keg;
4738 	KEG_LOCK_ASSERT(keg, slab->us_domain);
4739 
4740 	/* Do we need to remove from any lists? */
4741 	dom = &keg->uk_domain[slab->us_domain];
4742 	if (slab->us_freecount + 1 == keg->uk_ipers) {
4743 		LIST_REMOVE(slab, us_link);
4744 		LIST_INSERT_HEAD(&dom->ud_free_slab, slab, us_link);
4745 		dom->ud_free_slabs++;
4746 	} else if (slab->us_freecount == 0) {
4747 		LIST_REMOVE(slab, us_link);
4748 		LIST_INSERT_HEAD(&dom->ud_part_slab, slab, us_link);
4749 	}
4750 
4751 	/* Slab management. */
4752 	freei = slab_item_index(slab, keg, item);
4753 	BIT_SET(keg->uk_ipers, freei, &slab->us_free);
4754 	slab->us_freecount++;
4755 
4756 	/* Keg statistics. */
4757 	dom->ud_free_items++;
4758 }
4759 
4760 static void
4761 zone_release(void *arg, void **bucket, int cnt)
4762 {
4763 	struct mtx *lock;
4764 	uma_zone_t zone;
4765 	uma_slab_t slab;
4766 	uma_keg_t keg;
4767 	uint8_t *mem;
4768 	void *item;
4769 	int i;
4770 
4771 	zone = arg;
4772 	keg = zone->uz_keg;
4773 	lock = NULL;
4774 	if (__predict_false((zone->uz_flags & UMA_ZFLAG_HASH) != 0))
4775 		lock = KEG_LOCK(keg, 0);
4776 	for (i = 0; i < cnt; i++) {
4777 		item = bucket[i];
4778 		if (__predict_true((zone->uz_flags & UMA_ZFLAG_VTOSLAB) != 0)) {
4779 			slab = vtoslab((vm_offset_t)item);
4780 		} else {
4781 			mem = (uint8_t *)((uintptr_t)item & (~UMA_SLAB_MASK));
4782 			if ((zone->uz_flags & UMA_ZFLAG_HASH) != 0)
4783 				slab = hash_sfind(&keg->uk_hash, mem);
4784 			else
4785 				slab = (uma_slab_t)(mem + keg->uk_pgoff);
4786 		}
4787 		if (lock != KEG_LOCKPTR(keg, slab->us_domain)) {
4788 			if (lock != NULL)
4789 				mtx_unlock(lock);
4790 			lock = KEG_LOCK(keg, slab->us_domain);
4791 		}
4792 		slab_free_item(zone, slab, item);
4793 	}
4794 	if (lock != NULL)
4795 		mtx_unlock(lock);
4796 }
4797 
4798 /*
4799  * Frees a single item to any zone.
4800  *
4801  * Arguments:
4802  *	zone   The zone to free to
4803  *	item   The item we're freeing
4804  *	udata  User supplied data for the dtor
4805  *	skip   Skip dtors and finis
4806  */
4807 static __noinline void
4808 zone_free_item(uma_zone_t zone, void *item, void *udata, enum zfreeskip skip)
4809 {
4810 
4811 	/*
4812 	 * If a free is sent directly to an SMR zone we have to
4813 	 * synchronize immediately because the item can instantly
4814 	 * be reallocated. This should only happen in degenerate
4815 	 * cases when no memory is available for per-cpu caches.
4816 	 */
4817 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0 && skip == SKIP_NONE)
4818 		smr_synchronize(zone->uz_smr);
4819 
4820 	item_dtor(zone, item, zone->uz_size, udata, skip);
4821 
4822 	if (skip < SKIP_FINI && zone->uz_fini) {
4823 		kasan_mark_item_valid(zone, item);
4824 		zone->uz_fini(item, zone->uz_size);
4825 		kasan_mark_item_invalid(zone, item);
4826 	}
4827 
4828 	zone->uz_release(zone->uz_arg, &item, 1);
4829 
4830 	if (skip & SKIP_CNT)
4831 		return;
4832 
4833 	counter_u64_add(zone->uz_frees, 1);
4834 
4835 	if (zone->uz_max_items > 0)
4836 		zone_free_limit(zone, 1);
4837 }
4838 
4839 /* See uma.h */
4840 int
4841 uma_zone_set_max(uma_zone_t zone, int nitems)
4842 {
4843 
4844 	/*
4845 	 * If the limit is small, we may need to constrain the maximum per-CPU
4846 	 * cache size, or disable caching entirely.
4847 	 */
4848 	uma_zone_set_maxcache(zone, nitems);
4849 
4850 	/*
4851 	 * XXX This can misbehave if the zone has any allocations with
4852 	 * no limit and a limit is imposed.  There is currently no
4853 	 * way to clear a limit.
4854 	 */
4855 	ZONE_LOCK(zone);
4856 	zone->uz_max_items = nitems;
4857 	zone->uz_flags |= UMA_ZFLAG_LIMIT;
4858 	zone_update_caches(zone);
4859 	/* We may need to wake waiters. */
4860 	wakeup(&zone->uz_max_items);
4861 	ZONE_UNLOCK(zone);
4862 
4863 	return (nitems);
4864 }
4865 
4866 /* See uma.h */
4867 void
4868 uma_zone_set_maxcache(uma_zone_t zone, int nitems)
4869 {
4870 	int bpcpu, bpdom, bsize, nb;
4871 
4872 	ZONE_LOCK(zone);
4873 
4874 	/*
4875 	 * Compute a lower bound on the number of items that may be cached in
4876 	 * the zone.  Each CPU gets at least two buckets, and for cross-domain
4877 	 * frees we use an additional bucket per CPU and per domain.  Select the
4878 	 * largest bucket size that does not exceed half of the requested limit,
4879 	 * with the left over space given to the full bucket cache.
4880 	 */
4881 	bpdom = 0;
4882 	bpcpu = 2;
4883 #ifdef NUMA
4884 	if ((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) != 0 && vm_ndomains > 1) {
4885 		bpcpu++;
4886 		bpdom++;
4887 	}
4888 #endif
4889 	nb = bpcpu * mp_ncpus + bpdom * vm_ndomains;
4890 	bsize = nitems / nb / 2;
4891 	if (bsize > BUCKET_MAX)
4892 		bsize = BUCKET_MAX;
4893 	else if (bsize == 0 && nitems / nb > 0)
4894 		bsize = 1;
4895 	zone->uz_bucket_size_max = zone->uz_bucket_size = bsize;
4896 	if (zone->uz_bucket_size_min > zone->uz_bucket_size_max)
4897 		zone->uz_bucket_size_min = zone->uz_bucket_size_max;
4898 	zone->uz_bucket_max = nitems - nb * bsize;
4899 	ZONE_UNLOCK(zone);
4900 }
4901 
4902 /* See uma.h */
4903 int
4904 uma_zone_get_max(uma_zone_t zone)
4905 {
4906 	int nitems;
4907 
4908 	nitems = atomic_load_64(&zone->uz_max_items);
4909 
4910 	return (nitems);
4911 }
4912 
4913 /* See uma.h */
4914 void
4915 uma_zone_set_warning(uma_zone_t zone, const char *warning)
4916 {
4917 
4918 	ZONE_ASSERT_COLD(zone);
4919 	zone->uz_warning = warning;
4920 }
4921 
4922 /* See uma.h */
4923 void
4924 uma_zone_set_maxaction(uma_zone_t zone, uma_maxaction_t maxaction)
4925 {
4926 
4927 	ZONE_ASSERT_COLD(zone);
4928 	TASK_INIT(&zone->uz_maxaction, 0, (task_fn_t *)maxaction, zone);
4929 }
4930 
4931 /* See uma.h */
4932 int
4933 uma_zone_get_cur(uma_zone_t zone)
4934 {
4935 	int64_t nitems;
4936 	u_int i;
4937 
4938 	nitems = 0;
4939 	if (zone->uz_allocs != EARLY_COUNTER && zone->uz_frees != EARLY_COUNTER)
4940 		nitems = counter_u64_fetch(zone->uz_allocs) -
4941 		    counter_u64_fetch(zone->uz_frees);
4942 	CPU_FOREACH(i)
4943 		nitems += atomic_load_64(&zone->uz_cpu[i].uc_allocs) -
4944 		    atomic_load_64(&zone->uz_cpu[i].uc_frees);
4945 
4946 	return (nitems < 0 ? 0 : nitems);
4947 }
4948 
4949 static uint64_t
4950 uma_zone_get_allocs(uma_zone_t zone)
4951 {
4952 	uint64_t nitems;
4953 	u_int i;
4954 
4955 	nitems = 0;
4956 	if (zone->uz_allocs != EARLY_COUNTER)
4957 		nitems = counter_u64_fetch(zone->uz_allocs);
4958 	CPU_FOREACH(i)
4959 		nitems += atomic_load_64(&zone->uz_cpu[i].uc_allocs);
4960 
4961 	return (nitems);
4962 }
4963 
4964 static uint64_t
4965 uma_zone_get_frees(uma_zone_t zone)
4966 {
4967 	uint64_t nitems;
4968 	u_int i;
4969 
4970 	nitems = 0;
4971 	if (zone->uz_frees != EARLY_COUNTER)
4972 		nitems = counter_u64_fetch(zone->uz_frees);
4973 	CPU_FOREACH(i)
4974 		nitems += atomic_load_64(&zone->uz_cpu[i].uc_frees);
4975 
4976 	return (nitems);
4977 }
4978 
4979 #ifdef INVARIANTS
4980 /* Used only for KEG_ASSERT_COLD(). */
4981 static uint64_t
4982 uma_keg_get_allocs(uma_keg_t keg)
4983 {
4984 	uma_zone_t z;
4985 	uint64_t nitems;
4986 
4987 	nitems = 0;
4988 	LIST_FOREACH(z, &keg->uk_zones, uz_link)
4989 		nitems += uma_zone_get_allocs(z);
4990 
4991 	return (nitems);
4992 }
4993 #endif
4994 
4995 /* See uma.h */
4996 void
4997 uma_zone_set_init(uma_zone_t zone, uma_init uminit)
4998 {
4999 	uma_keg_t keg;
5000 
5001 	KEG_GET(zone, keg);
5002 	KEG_ASSERT_COLD(keg);
5003 	keg->uk_init = uminit;
5004 }
5005 
5006 /* See uma.h */
5007 void
5008 uma_zone_set_fini(uma_zone_t zone, uma_fini fini)
5009 {
5010 	uma_keg_t keg;
5011 
5012 	KEG_GET(zone, keg);
5013 	KEG_ASSERT_COLD(keg);
5014 	keg->uk_fini = fini;
5015 }
5016 
5017 /* See uma.h */
5018 void
5019 uma_zone_set_zinit(uma_zone_t zone, uma_init zinit)
5020 {
5021 
5022 	ZONE_ASSERT_COLD(zone);
5023 	zone->uz_init = zinit;
5024 }
5025 
5026 /* See uma.h */
5027 void
5028 uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini)
5029 {
5030 
5031 	ZONE_ASSERT_COLD(zone);
5032 	zone->uz_fini = zfini;
5033 }
5034 
5035 /* See uma.h */
5036 void
5037 uma_zone_set_freef(uma_zone_t zone, uma_free freef)
5038 {
5039 	uma_keg_t keg;
5040 
5041 	KEG_GET(zone, keg);
5042 	KEG_ASSERT_COLD(keg);
5043 	keg->uk_freef = freef;
5044 }
5045 
5046 /* See uma.h */
5047 void
5048 uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf)
5049 {
5050 	uma_keg_t keg;
5051 
5052 	KEG_GET(zone, keg);
5053 	KEG_ASSERT_COLD(keg);
5054 	keg->uk_allocf = allocf;
5055 }
5056 
5057 /* See uma.h */
5058 void
5059 uma_zone_set_smr(uma_zone_t zone, smr_t smr)
5060 {
5061 
5062 	ZONE_ASSERT_COLD(zone);
5063 
5064 	KASSERT(smr != NULL, ("Got NULL smr"));
5065 	KASSERT((zone->uz_flags & UMA_ZONE_SMR) == 0,
5066 	    ("zone %p (%s) already uses SMR", zone, zone->uz_name));
5067 	zone->uz_flags |= UMA_ZONE_SMR;
5068 	zone->uz_smr = smr;
5069 	zone_update_caches(zone);
5070 }
5071 
5072 smr_t
5073 uma_zone_get_smr(uma_zone_t zone)
5074 {
5075 
5076 	return (zone->uz_smr);
5077 }
5078 
5079 /* See uma.h */
5080 void
5081 uma_zone_reserve(uma_zone_t zone, int items)
5082 {
5083 	uma_keg_t keg;
5084 
5085 	KEG_GET(zone, keg);
5086 	KEG_ASSERT_COLD(keg);
5087 	keg->uk_reserve = items;
5088 }
5089 
5090 /* See uma.h */
5091 int
5092 uma_zone_reserve_kva(uma_zone_t zone, int count)
5093 {
5094 	uma_keg_t keg;
5095 	vm_offset_t kva;
5096 	u_int pages;
5097 
5098 	KEG_GET(zone, keg);
5099 	KEG_ASSERT_COLD(keg);
5100 	ZONE_ASSERT_COLD(zone);
5101 
5102 	pages = howmany(count, keg->uk_ipers) * keg->uk_ppera;
5103 
5104 #ifdef UMA_MD_SMALL_ALLOC
5105 	if (keg->uk_ppera > 1) {
5106 #else
5107 	if (1) {
5108 #endif
5109 		kva = kva_alloc((vm_size_t)pages * PAGE_SIZE);
5110 		if (kva == 0)
5111 			return (0);
5112 	} else
5113 		kva = 0;
5114 
5115 	MPASS(keg->uk_kva == 0);
5116 	keg->uk_kva = kva;
5117 	keg->uk_offset = 0;
5118 	zone->uz_max_items = pages * keg->uk_ipers;
5119 #ifdef UMA_MD_SMALL_ALLOC
5120 	keg->uk_allocf = (keg->uk_ppera > 1) ? noobj_alloc : uma_small_alloc;
5121 #else
5122 	keg->uk_allocf = noobj_alloc;
5123 #endif
5124 	keg->uk_flags |= UMA_ZFLAG_LIMIT | UMA_ZONE_NOFREE;
5125 	zone->uz_flags |= UMA_ZFLAG_LIMIT | UMA_ZONE_NOFREE;
5126 	zone_update_caches(zone);
5127 
5128 	return (1);
5129 }
5130 
5131 /* See uma.h */
5132 void
5133 uma_prealloc(uma_zone_t zone, int items)
5134 {
5135 	struct vm_domainset_iter di;
5136 	uma_domain_t dom;
5137 	uma_slab_t slab;
5138 	uma_keg_t keg;
5139 	int aflags, domain, slabs;
5140 
5141 	KEG_GET(zone, keg);
5142 	slabs = howmany(items, keg->uk_ipers);
5143 	while (slabs-- > 0) {
5144 		aflags = M_NOWAIT;
5145 		vm_domainset_iter_policy_ref_init(&di, &keg->uk_dr, &domain,
5146 		    &aflags);
5147 		for (;;) {
5148 			slab = keg_alloc_slab(keg, zone, domain, M_WAITOK,
5149 			    aflags);
5150 			if (slab != NULL) {
5151 				dom = &keg->uk_domain[slab->us_domain];
5152 				/*
5153 				 * keg_alloc_slab() always returns a slab on the
5154 				 * partial list.
5155 				 */
5156 				LIST_REMOVE(slab, us_link);
5157 				LIST_INSERT_HEAD(&dom->ud_free_slab, slab,
5158 				    us_link);
5159 				dom->ud_free_slabs++;
5160 				KEG_UNLOCK(keg, slab->us_domain);
5161 				break;
5162 			}
5163 			if (vm_domainset_iter_policy(&di, &domain) != 0)
5164 				vm_wait_doms(&keg->uk_dr.dr_policy->ds_mask, 0);
5165 		}
5166 	}
5167 }
5168 
5169 /*
5170  * Returns a snapshot of memory consumption in bytes.
5171  */
5172 size_t
5173 uma_zone_memory(uma_zone_t zone)
5174 {
5175 	size_t sz;
5176 	int i;
5177 
5178 	sz = 0;
5179 	if (zone->uz_flags & UMA_ZFLAG_CACHE) {
5180 		for (i = 0; i < vm_ndomains; i++)
5181 			sz += ZDOM_GET(zone, i)->uzd_nitems;
5182 		return (sz * zone->uz_size);
5183 	}
5184 	for (i = 0; i < vm_ndomains; i++)
5185 		sz += zone->uz_keg->uk_domain[i].ud_pages;
5186 
5187 	return (sz * PAGE_SIZE);
5188 }
5189 
5190 struct uma_reclaim_args {
5191 	int	domain;
5192 	int	req;
5193 };
5194 
5195 static void
5196 uma_reclaim_domain_cb(uma_zone_t zone, void *arg)
5197 {
5198 	struct uma_reclaim_args *args;
5199 
5200 	args = arg;
5201 	if ((zone->uz_flags & UMA_ZONE_UNMANAGED) == 0)
5202 		uma_zone_reclaim_domain(zone, args->req, args->domain);
5203 }
5204 
5205 /* See uma.h */
5206 void
5207 uma_reclaim(int req)
5208 {
5209 	uma_reclaim_domain(req, UMA_ANYDOMAIN);
5210 }
5211 
5212 void
5213 uma_reclaim_domain(int req, int domain)
5214 {
5215 	struct uma_reclaim_args args;
5216 
5217 	bucket_enable();
5218 
5219 	args.domain = domain;
5220 	args.req = req;
5221 
5222 	sx_slock(&uma_reclaim_lock);
5223 	switch (req) {
5224 	case UMA_RECLAIM_TRIM:
5225 	case UMA_RECLAIM_DRAIN:
5226 		zone_foreach(uma_reclaim_domain_cb, &args);
5227 		break;
5228 	case UMA_RECLAIM_DRAIN_CPU:
5229 		zone_foreach(uma_reclaim_domain_cb, &args);
5230 		pcpu_cache_drain_safe(NULL);
5231 		zone_foreach(uma_reclaim_domain_cb, &args);
5232 		break;
5233 	default:
5234 		panic("unhandled reclamation request %d", req);
5235 	}
5236 
5237 	/*
5238 	 * Some slabs may have been freed but this zone will be visited early
5239 	 * we visit again so that we can free pages that are empty once other
5240 	 * zones are drained.  We have to do the same for buckets.
5241 	 */
5242 	uma_zone_reclaim_domain(slabzones[0], UMA_RECLAIM_DRAIN, domain);
5243 	uma_zone_reclaim_domain(slabzones[1], UMA_RECLAIM_DRAIN, domain);
5244 	bucket_zone_drain(domain);
5245 	sx_sunlock(&uma_reclaim_lock);
5246 }
5247 
5248 static volatile int uma_reclaim_needed;
5249 
5250 void
5251 uma_reclaim_wakeup(void)
5252 {
5253 
5254 	if (atomic_fetchadd_int(&uma_reclaim_needed, 1) == 0)
5255 		wakeup(uma_reclaim);
5256 }
5257 
5258 void
5259 uma_reclaim_worker(void *arg __unused)
5260 {
5261 
5262 	for (;;) {
5263 		sx_xlock(&uma_reclaim_lock);
5264 		while (atomic_load_int(&uma_reclaim_needed) == 0)
5265 			sx_sleep(uma_reclaim, &uma_reclaim_lock, PVM, "umarcl",
5266 			    hz);
5267 		sx_xunlock(&uma_reclaim_lock);
5268 		EVENTHANDLER_INVOKE(vm_lowmem, VM_LOW_KMEM);
5269 		uma_reclaim(UMA_RECLAIM_DRAIN_CPU);
5270 		atomic_store_int(&uma_reclaim_needed, 0);
5271 		/* Don't fire more than once per-second. */
5272 		pause("umarclslp", hz);
5273 	}
5274 }
5275 
5276 /* See uma.h */
5277 void
5278 uma_zone_reclaim(uma_zone_t zone, int req)
5279 {
5280 	uma_zone_reclaim_domain(zone, req, UMA_ANYDOMAIN);
5281 }
5282 
5283 void
5284 uma_zone_reclaim_domain(uma_zone_t zone, int req, int domain)
5285 {
5286 	switch (req) {
5287 	case UMA_RECLAIM_TRIM:
5288 		zone_reclaim(zone, domain, M_NOWAIT, false);
5289 		break;
5290 	case UMA_RECLAIM_DRAIN:
5291 		zone_reclaim(zone, domain, M_NOWAIT, true);
5292 		break;
5293 	case UMA_RECLAIM_DRAIN_CPU:
5294 		pcpu_cache_drain_safe(zone);
5295 		zone_reclaim(zone, domain, M_NOWAIT, true);
5296 		break;
5297 	default:
5298 		panic("unhandled reclamation request %d", req);
5299 	}
5300 }
5301 
5302 /* See uma.h */
5303 int
5304 uma_zone_exhausted(uma_zone_t zone)
5305 {
5306 
5307 	return (atomic_load_32(&zone->uz_sleepers) > 0);
5308 }
5309 
5310 unsigned long
5311 uma_limit(void)
5312 {
5313 
5314 	return (uma_kmem_limit);
5315 }
5316 
5317 void
5318 uma_set_limit(unsigned long limit)
5319 {
5320 
5321 	uma_kmem_limit = limit;
5322 }
5323 
5324 unsigned long
5325 uma_size(void)
5326 {
5327 
5328 	return (atomic_load_long(&uma_kmem_total));
5329 }
5330 
5331 long
5332 uma_avail(void)
5333 {
5334 
5335 	return (uma_kmem_limit - uma_size());
5336 }
5337 
5338 #ifdef DDB
5339 /*
5340  * Generate statistics across both the zone and its per-cpu cache's.  Return
5341  * desired statistics if the pointer is non-NULL for that statistic.
5342  *
5343  * Note: does not update the zone statistics, as it can't safely clear the
5344  * per-CPU cache statistic.
5345  *
5346  */
5347 static void
5348 uma_zone_sumstat(uma_zone_t z, long *cachefreep, uint64_t *allocsp,
5349     uint64_t *freesp, uint64_t *sleepsp, uint64_t *xdomainp)
5350 {
5351 	uma_cache_t cache;
5352 	uint64_t allocs, frees, sleeps, xdomain;
5353 	int cachefree, cpu;
5354 
5355 	allocs = frees = sleeps = xdomain = 0;
5356 	cachefree = 0;
5357 	CPU_FOREACH(cpu) {
5358 		cache = &z->uz_cpu[cpu];
5359 		cachefree += cache->uc_allocbucket.ucb_cnt;
5360 		cachefree += cache->uc_freebucket.ucb_cnt;
5361 		xdomain += cache->uc_crossbucket.ucb_cnt;
5362 		cachefree += cache->uc_crossbucket.ucb_cnt;
5363 		allocs += cache->uc_allocs;
5364 		frees += cache->uc_frees;
5365 	}
5366 	allocs += counter_u64_fetch(z->uz_allocs);
5367 	frees += counter_u64_fetch(z->uz_frees);
5368 	xdomain += counter_u64_fetch(z->uz_xdomain);
5369 	sleeps += z->uz_sleeps;
5370 	if (cachefreep != NULL)
5371 		*cachefreep = cachefree;
5372 	if (allocsp != NULL)
5373 		*allocsp = allocs;
5374 	if (freesp != NULL)
5375 		*freesp = frees;
5376 	if (sleepsp != NULL)
5377 		*sleepsp = sleeps;
5378 	if (xdomainp != NULL)
5379 		*xdomainp = xdomain;
5380 }
5381 #endif /* DDB */
5382 
5383 static int
5384 sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS)
5385 {
5386 	uma_keg_t kz;
5387 	uma_zone_t z;
5388 	int count;
5389 
5390 	count = 0;
5391 	rw_rlock(&uma_rwlock);
5392 	LIST_FOREACH(kz, &uma_kegs, uk_link) {
5393 		LIST_FOREACH(z, &kz->uk_zones, uz_link)
5394 			count++;
5395 	}
5396 	LIST_FOREACH(z, &uma_cachezones, uz_link)
5397 		count++;
5398 
5399 	rw_runlock(&uma_rwlock);
5400 	return (sysctl_handle_int(oidp, &count, 0, req));
5401 }
5402 
5403 static void
5404 uma_vm_zone_stats(struct uma_type_header *uth, uma_zone_t z, struct sbuf *sbuf,
5405     struct uma_percpu_stat *ups, bool internal)
5406 {
5407 	uma_zone_domain_t zdom;
5408 	uma_cache_t cache;
5409 	int i;
5410 
5411 	for (i = 0; i < vm_ndomains; i++) {
5412 		zdom = ZDOM_GET(z, i);
5413 		uth->uth_zone_free += zdom->uzd_nitems;
5414 	}
5415 	uth->uth_allocs = counter_u64_fetch(z->uz_allocs);
5416 	uth->uth_frees = counter_u64_fetch(z->uz_frees);
5417 	uth->uth_fails = counter_u64_fetch(z->uz_fails);
5418 	uth->uth_xdomain = counter_u64_fetch(z->uz_xdomain);
5419 	uth->uth_sleeps = z->uz_sleeps;
5420 
5421 	for (i = 0; i < mp_maxid + 1; i++) {
5422 		bzero(&ups[i], sizeof(*ups));
5423 		if (internal || CPU_ABSENT(i))
5424 			continue;
5425 		cache = &z->uz_cpu[i];
5426 		ups[i].ups_cache_free += cache->uc_allocbucket.ucb_cnt;
5427 		ups[i].ups_cache_free += cache->uc_freebucket.ucb_cnt;
5428 		ups[i].ups_cache_free += cache->uc_crossbucket.ucb_cnt;
5429 		ups[i].ups_allocs = cache->uc_allocs;
5430 		ups[i].ups_frees = cache->uc_frees;
5431 	}
5432 }
5433 
5434 static int
5435 sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS)
5436 {
5437 	struct uma_stream_header ush;
5438 	struct uma_type_header uth;
5439 	struct uma_percpu_stat *ups;
5440 	struct sbuf sbuf;
5441 	uma_keg_t kz;
5442 	uma_zone_t z;
5443 	uint64_t items;
5444 	uint32_t kfree, pages;
5445 	int count, error, i;
5446 
5447 	error = sysctl_wire_old_buffer(req, 0);
5448 	if (error != 0)
5449 		return (error);
5450 	sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
5451 	sbuf_clear_flags(&sbuf, SBUF_INCLUDENUL);
5452 	ups = malloc((mp_maxid + 1) * sizeof(*ups), M_TEMP, M_WAITOK);
5453 
5454 	count = 0;
5455 	rw_rlock(&uma_rwlock);
5456 	LIST_FOREACH(kz, &uma_kegs, uk_link) {
5457 		LIST_FOREACH(z, &kz->uk_zones, uz_link)
5458 			count++;
5459 	}
5460 
5461 	LIST_FOREACH(z, &uma_cachezones, uz_link)
5462 		count++;
5463 
5464 	/*
5465 	 * Insert stream header.
5466 	 */
5467 	bzero(&ush, sizeof(ush));
5468 	ush.ush_version = UMA_STREAM_VERSION;
5469 	ush.ush_maxcpus = (mp_maxid + 1);
5470 	ush.ush_count = count;
5471 	(void)sbuf_bcat(&sbuf, &ush, sizeof(ush));
5472 
5473 	LIST_FOREACH(kz, &uma_kegs, uk_link) {
5474 		kfree = pages = 0;
5475 		for (i = 0; i < vm_ndomains; i++) {
5476 			kfree += kz->uk_domain[i].ud_free_items;
5477 			pages += kz->uk_domain[i].ud_pages;
5478 		}
5479 		LIST_FOREACH(z, &kz->uk_zones, uz_link) {
5480 			bzero(&uth, sizeof(uth));
5481 			strlcpy(uth.uth_name, z->uz_name, UTH_MAX_NAME);
5482 			uth.uth_align = kz->uk_align;
5483 			uth.uth_size = kz->uk_size;
5484 			uth.uth_rsize = kz->uk_rsize;
5485 			if (z->uz_max_items > 0) {
5486 				items = UZ_ITEMS_COUNT(z->uz_items);
5487 				uth.uth_pages = (items / kz->uk_ipers) *
5488 					kz->uk_ppera;
5489 			} else
5490 				uth.uth_pages = pages;
5491 			uth.uth_maxpages = (z->uz_max_items / kz->uk_ipers) *
5492 			    kz->uk_ppera;
5493 			uth.uth_limit = z->uz_max_items;
5494 			uth.uth_keg_free = kfree;
5495 
5496 			/*
5497 			 * A zone is secondary is it is not the first entry
5498 			 * on the keg's zone list.
5499 			 */
5500 			if ((z->uz_flags & UMA_ZONE_SECONDARY) &&
5501 			    (LIST_FIRST(&kz->uk_zones) != z))
5502 				uth.uth_zone_flags = UTH_ZONE_SECONDARY;
5503 			uma_vm_zone_stats(&uth, z, &sbuf, ups,
5504 			    kz->uk_flags & UMA_ZFLAG_INTERNAL);
5505 			(void)sbuf_bcat(&sbuf, &uth, sizeof(uth));
5506 			for (i = 0; i < mp_maxid + 1; i++)
5507 				(void)sbuf_bcat(&sbuf, &ups[i], sizeof(ups[i]));
5508 		}
5509 	}
5510 	LIST_FOREACH(z, &uma_cachezones, uz_link) {
5511 		bzero(&uth, sizeof(uth));
5512 		strlcpy(uth.uth_name, z->uz_name, UTH_MAX_NAME);
5513 		uth.uth_size = z->uz_size;
5514 		uma_vm_zone_stats(&uth, z, &sbuf, ups, false);
5515 		(void)sbuf_bcat(&sbuf, &uth, sizeof(uth));
5516 		for (i = 0; i < mp_maxid + 1; i++)
5517 			(void)sbuf_bcat(&sbuf, &ups[i], sizeof(ups[i]));
5518 	}
5519 
5520 	rw_runlock(&uma_rwlock);
5521 	error = sbuf_finish(&sbuf);
5522 	sbuf_delete(&sbuf);
5523 	free(ups, M_TEMP);
5524 	return (error);
5525 }
5526 
5527 int
5528 sysctl_handle_uma_zone_max(SYSCTL_HANDLER_ARGS)
5529 {
5530 	uma_zone_t zone = *(uma_zone_t *)arg1;
5531 	int error, max;
5532 
5533 	max = uma_zone_get_max(zone);
5534 	error = sysctl_handle_int(oidp, &max, 0, req);
5535 	if (error || !req->newptr)
5536 		return (error);
5537 
5538 	uma_zone_set_max(zone, max);
5539 
5540 	return (0);
5541 }
5542 
5543 int
5544 sysctl_handle_uma_zone_cur(SYSCTL_HANDLER_ARGS)
5545 {
5546 	uma_zone_t zone;
5547 	int cur;
5548 
5549 	/*
5550 	 * Some callers want to add sysctls for global zones that
5551 	 * may not yet exist so they pass a pointer to a pointer.
5552 	 */
5553 	if (arg2 == 0)
5554 		zone = *(uma_zone_t *)arg1;
5555 	else
5556 		zone = arg1;
5557 	cur = uma_zone_get_cur(zone);
5558 	return (sysctl_handle_int(oidp, &cur, 0, req));
5559 }
5560 
5561 static int
5562 sysctl_handle_uma_zone_allocs(SYSCTL_HANDLER_ARGS)
5563 {
5564 	uma_zone_t zone = arg1;
5565 	uint64_t cur;
5566 
5567 	cur = uma_zone_get_allocs(zone);
5568 	return (sysctl_handle_64(oidp, &cur, 0, req));
5569 }
5570 
5571 static int
5572 sysctl_handle_uma_zone_frees(SYSCTL_HANDLER_ARGS)
5573 {
5574 	uma_zone_t zone = arg1;
5575 	uint64_t cur;
5576 
5577 	cur = uma_zone_get_frees(zone);
5578 	return (sysctl_handle_64(oidp, &cur, 0, req));
5579 }
5580 
5581 static int
5582 sysctl_handle_uma_zone_flags(SYSCTL_HANDLER_ARGS)
5583 {
5584 	struct sbuf sbuf;
5585 	uma_zone_t zone = arg1;
5586 	int error;
5587 
5588 	sbuf_new_for_sysctl(&sbuf, NULL, 0, req);
5589 	if (zone->uz_flags != 0)
5590 		sbuf_printf(&sbuf, "0x%b", zone->uz_flags, PRINT_UMA_ZFLAGS);
5591 	else
5592 		sbuf_printf(&sbuf, "0");
5593 	error = sbuf_finish(&sbuf);
5594 	sbuf_delete(&sbuf);
5595 
5596 	return (error);
5597 }
5598 
5599 static int
5600 sysctl_handle_uma_slab_efficiency(SYSCTL_HANDLER_ARGS)
5601 {
5602 	uma_keg_t keg = arg1;
5603 	int avail, effpct, total;
5604 
5605 	total = keg->uk_ppera * PAGE_SIZE;
5606 	if ((keg->uk_flags & UMA_ZFLAG_OFFPAGE) != 0)
5607 		total += slabzone(keg->uk_ipers)->uz_keg->uk_rsize;
5608 	/*
5609 	 * We consider the client's requested size and alignment here, not the
5610 	 * real size determination uk_rsize, because we also adjust the real
5611 	 * size for internal implementation reasons (max bitset size).
5612 	 */
5613 	avail = keg->uk_ipers * roundup2(keg->uk_size, keg->uk_align + 1);
5614 	if ((keg->uk_flags & UMA_ZONE_PCPU) != 0)
5615 		avail *= mp_maxid + 1;
5616 	effpct = 100 * avail / total;
5617 	return (sysctl_handle_int(oidp, &effpct, 0, req));
5618 }
5619 
5620 static int
5621 sysctl_handle_uma_zone_items(SYSCTL_HANDLER_ARGS)
5622 {
5623 	uma_zone_t zone = arg1;
5624 	uint64_t cur;
5625 
5626 	cur = UZ_ITEMS_COUNT(atomic_load_64(&zone->uz_items));
5627 	return (sysctl_handle_64(oidp, &cur, 0, req));
5628 }
5629 
5630 #ifdef INVARIANTS
5631 static uma_slab_t
5632 uma_dbg_getslab(uma_zone_t zone, void *item)
5633 {
5634 	uma_slab_t slab;
5635 	uma_keg_t keg;
5636 	uint8_t *mem;
5637 
5638 	/*
5639 	 * It is safe to return the slab here even though the
5640 	 * zone is unlocked because the item's allocation state
5641 	 * essentially holds a reference.
5642 	 */
5643 	mem = (uint8_t *)((uintptr_t)item & (~UMA_SLAB_MASK));
5644 	if ((zone->uz_flags & UMA_ZFLAG_CACHE) != 0)
5645 		return (NULL);
5646 	if (zone->uz_flags & UMA_ZFLAG_VTOSLAB)
5647 		return (vtoslab((vm_offset_t)mem));
5648 	keg = zone->uz_keg;
5649 	if ((keg->uk_flags & UMA_ZFLAG_HASH) == 0)
5650 		return ((uma_slab_t)(mem + keg->uk_pgoff));
5651 	KEG_LOCK(keg, 0);
5652 	slab = hash_sfind(&keg->uk_hash, mem);
5653 	KEG_UNLOCK(keg, 0);
5654 
5655 	return (slab);
5656 }
5657 
5658 static bool
5659 uma_dbg_zskip(uma_zone_t zone, void *mem)
5660 {
5661 
5662 	if ((zone->uz_flags & UMA_ZFLAG_CACHE) != 0)
5663 		return (true);
5664 
5665 	return (uma_dbg_kskip(zone->uz_keg, mem));
5666 }
5667 
5668 static bool
5669 uma_dbg_kskip(uma_keg_t keg, void *mem)
5670 {
5671 	uintptr_t idx;
5672 
5673 	if (dbg_divisor == 0)
5674 		return (true);
5675 
5676 	if (dbg_divisor == 1)
5677 		return (false);
5678 
5679 	idx = (uintptr_t)mem >> PAGE_SHIFT;
5680 	if (keg->uk_ipers > 1) {
5681 		idx *= keg->uk_ipers;
5682 		idx += ((uintptr_t)mem & PAGE_MASK) / keg->uk_rsize;
5683 	}
5684 
5685 	if ((idx / dbg_divisor) * dbg_divisor != idx) {
5686 		counter_u64_add(uma_skip_cnt, 1);
5687 		return (true);
5688 	}
5689 	counter_u64_add(uma_dbg_cnt, 1);
5690 
5691 	return (false);
5692 }
5693 
5694 /*
5695  * Set up the slab's freei data such that uma_dbg_free can function.
5696  *
5697  */
5698 static void
5699 uma_dbg_alloc(uma_zone_t zone, uma_slab_t slab, void *item)
5700 {
5701 	uma_keg_t keg;
5702 	int freei;
5703 
5704 	if (slab == NULL) {
5705 		slab = uma_dbg_getslab(zone, item);
5706 		if (slab == NULL)
5707 			panic("uma: item %p did not belong to zone %s",
5708 			    item, zone->uz_name);
5709 	}
5710 	keg = zone->uz_keg;
5711 	freei = slab_item_index(slab, keg, item);
5712 
5713 	if (BIT_TEST_SET_ATOMIC(keg->uk_ipers, freei,
5714 	    slab_dbg_bits(slab, keg)))
5715 		panic("Duplicate alloc of %p from zone %p(%s) slab %p(%d)",
5716 		    item, zone, zone->uz_name, slab, freei);
5717 }
5718 
5719 /*
5720  * Verifies freed addresses.  Checks for alignment, valid slab membership
5721  * and duplicate frees.
5722  *
5723  */
5724 static void
5725 uma_dbg_free(uma_zone_t zone, uma_slab_t slab, void *item)
5726 {
5727 	uma_keg_t keg;
5728 	int freei;
5729 
5730 	if (slab == NULL) {
5731 		slab = uma_dbg_getslab(zone, item);
5732 		if (slab == NULL)
5733 			panic("uma: Freed item %p did not belong to zone %s",
5734 			    item, zone->uz_name);
5735 	}
5736 	keg = zone->uz_keg;
5737 	freei = slab_item_index(slab, keg, item);
5738 
5739 	if (freei >= keg->uk_ipers)
5740 		panic("Invalid free of %p from zone %p(%s) slab %p(%d)",
5741 		    item, zone, zone->uz_name, slab, freei);
5742 
5743 	if (slab_item(slab, keg, freei) != item)
5744 		panic("Unaligned free of %p from zone %p(%s) slab %p(%d)",
5745 		    item, zone, zone->uz_name, slab, freei);
5746 
5747 	if (!BIT_TEST_CLR_ATOMIC(keg->uk_ipers, freei,
5748 	    slab_dbg_bits(slab, keg)))
5749 		panic("Duplicate free of %p from zone %p(%s) slab %p(%d)",
5750 		    item, zone, zone->uz_name, slab, freei);
5751 }
5752 #endif /* INVARIANTS */
5753 
5754 #ifdef DDB
5755 static int64_t
5756 get_uma_stats(uma_keg_t kz, uma_zone_t z, uint64_t *allocs, uint64_t *used,
5757     uint64_t *sleeps, long *cachefree, uint64_t *xdomain)
5758 {
5759 	uint64_t frees;
5760 	int i;
5761 
5762 	if (kz->uk_flags & UMA_ZFLAG_INTERNAL) {
5763 		*allocs = counter_u64_fetch(z->uz_allocs);
5764 		frees = counter_u64_fetch(z->uz_frees);
5765 		*sleeps = z->uz_sleeps;
5766 		*cachefree = 0;
5767 		*xdomain = 0;
5768 	} else
5769 		uma_zone_sumstat(z, cachefree, allocs, &frees, sleeps,
5770 		    xdomain);
5771 	for (i = 0; i < vm_ndomains; i++) {
5772 		*cachefree += ZDOM_GET(z, i)->uzd_nitems;
5773 		if (!((z->uz_flags & UMA_ZONE_SECONDARY) &&
5774 		    (LIST_FIRST(&kz->uk_zones) != z)))
5775 			*cachefree += kz->uk_domain[i].ud_free_items;
5776 	}
5777 	*used = *allocs - frees;
5778 	return (((int64_t)*used + *cachefree) * kz->uk_size);
5779 }
5780 
5781 DB_SHOW_COMMAND(uma, db_show_uma)
5782 {
5783 	const char *fmt_hdr, *fmt_entry;
5784 	uma_keg_t kz;
5785 	uma_zone_t z;
5786 	uint64_t allocs, used, sleeps, xdomain;
5787 	long cachefree;
5788 	/* variables for sorting */
5789 	uma_keg_t cur_keg;
5790 	uma_zone_t cur_zone, last_zone;
5791 	int64_t cur_size, last_size, size;
5792 	int ties;
5793 
5794 	/* /i option produces machine-parseable CSV output */
5795 	if (modif[0] == 'i') {
5796 		fmt_hdr = "%s,%s,%s,%s,%s,%s,%s,%s,%s\n";
5797 		fmt_entry = "\"%s\",%ju,%jd,%ld,%ju,%ju,%u,%jd,%ju\n";
5798 	} else {
5799 		fmt_hdr = "%18s %6s %7s %7s %11s %7s %7s %10s %8s\n";
5800 		fmt_entry = "%18s %6ju %7jd %7ld %11ju %7ju %7u %10jd %8ju\n";
5801 	}
5802 
5803 	db_printf(fmt_hdr, "Zone", "Size", "Used", "Free", "Requests",
5804 	    "Sleeps", "Bucket", "Total Mem", "XFree");
5805 
5806 	/* Sort the zones with largest size first. */
5807 	last_zone = NULL;
5808 	last_size = INT64_MAX;
5809 	for (;;) {
5810 		cur_zone = NULL;
5811 		cur_size = -1;
5812 		ties = 0;
5813 		LIST_FOREACH(kz, &uma_kegs, uk_link) {
5814 			LIST_FOREACH(z, &kz->uk_zones, uz_link) {
5815 				/*
5816 				 * In the case of size ties, print out zones
5817 				 * in the order they are encountered.  That is,
5818 				 * when we encounter the most recently output
5819 				 * zone, we have already printed all preceding
5820 				 * ties, and we must print all following ties.
5821 				 */
5822 				if (z == last_zone) {
5823 					ties = 1;
5824 					continue;
5825 				}
5826 				size = get_uma_stats(kz, z, &allocs, &used,
5827 				    &sleeps, &cachefree, &xdomain);
5828 				if (size > cur_size && size < last_size + ties)
5829 				{
5830 					cur_size = size;
5831 					cur_zone = z;
5832 					cur_keg = kz;
5833 				}
5834 			}
5835 		}
5836 		if (cur_zone == NULL)
5837 			break;
5838 
5839 		size = get_uma_stats(cur_keg, cur_zone, &allocs, &used,
5840 		    &sleeps, &cachefree, &xdomain);
5841 		db_printf(fmt_entry, cur_zone->uz_name,
5842 		    (uintmax_t)cur_keg->uk_size, (intmax_t)used, cachefree,
5843 		    (uintmax_t)allocs, (uintmax_t)sleeps,
5844 		    (unsigned)cur_zone->uz_bucket_size, (intmax_t)size,
5845 		    xdomain);
5846 
5847 		if (db_pager_quit)
5848 			return;
5849 		last_zone = cur_zone;
5850 		last_size = cur_size;
5851 	}
5852 }
5853 
5854 DB_SHOW_COMMAND(umacache, db_show_umacache)
5855 {
5856 	uma_zone_t z;
5857 	uint64_t allocs, frees;
5858 	long cachefree;
5859 	int i;
5860 
5861 	db_printf("%18s %8s %8s %8s %12s %8s\n", "Zone", "Size", "Used", "Free",
5862 	    "Requests", "Bucket");
5863 	LIST_FOREACH(z, &uma_cachezones, uz_link) {
5864 		uma_zone_sumstat(z, &cachefree, &allocs, &frees, NULL, NULL);
5865 		for (i = 0; i < vm_ndomains; i++)
5866 			cachefree += ZDOM_GET(z, i)->uzd_nitems;
5867 		db_printf("%18s %8ju %8jd %8ld %12ju %8u\n",
5868 		    z->uz_name, (uintmax_t)z->uz_size,
5869 		    (intmax_t)(allocs - frees), cachefree,
5870 		    (uintmax_t)allocs, z->uz_bucket_size);
5871 		if (db_pager_quit)
5872 			return;
5873 	}
5874 }
5875 #endif	/* DDB */
5876