2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice unmodified, this list of conditions, and the following
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.
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.
32 * uma_core.c Implementation of the Universal Memory allocator
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.
41 * The basic ideas stem from similar slab/zone based allocators whose algorithms
48 * - Improve memory usage for large allocations
49 * - Investigate cache size adjustments
52 #include <sys/cdefs.h>
53 __FBSDID("$FreeBSD$");
56 #include "opt_param.h"
59 #include <sys/param.h>
60 #include <sys/systm.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>
72 #include <sys/sysctl.h>
73 #include <sys/mutex.h>
75 #include <sys/random.h>
76 #include <sys/rwlock.h>
78 #include <sys/sched.h>
79 #include <sys/sleepqueue.h>
82 #include <sys/taskqueue.h>
83 #include <sys/vmmeter.h>
86 #include <vm/vm_param.h>
87 #include <vm/vm_domainset.h>
88 #include <vm/vm_object.h>
89 #include <vm/vm_page.h>
90 #include <vm/vm_pageout.h>
91 #include <vm/vm_phys.h>
92 #include <vm/vm_pagequeue.h>
93 #include <vm/vm_map.h>
94 #include <vm/vm_kern.h>
95 #include <vm/vm_extern.h>
96 #include <vm/vm_dumpset.h>
98 #include <vm/uma_int.h>
99 #include <vm/uma_dbg.h>
103 #ifdef DEBUG_MEMGUARD
104 #include <vm/memguard.h>
107 #include <machine/md_var.h>
110 #define UMA_ALWAYS_CTORDTOR 1
112 #define UMA_ALWAYS_CTORDTOR 0
116 * This is the zone and keg from which all zones are spawned.
118 static uma_zone_t kegs;
119 static uma_zone_t zones;
122 * On INVARIANTS builds, the slab contains a second bitset of the same size,
123 * "dbg_bits", which is laid out immediately after us_free.
126 #define SLAB_BITSETS 2
128 #define SLAB_BITSETS 1
132 * These are the two zones from which all offpage uma_slab_ts are allocated.
134 * One zone is for slab headers that can represent a larger number of items,
135 * making the slabs themselves more efficient, and the other zone is for
136 * headers that are smaller and represent fewer items, making the headers more
139 #define SLABZONE_SIZE(setsize) \
140 (sizeof(struct uma_hash_slab) + BITSET_SIZE(setsize) * SLAB_BITSETS)
141 #define SLABZONE0_SETSIZE (PAGE_SIZE / 16)
142 #define SLABZONE1_SETSIZE SLAB_MAX_SETSIZE
143 #define SLABZONE0_SIZE SLABZONE_SIZE(SLABZONE0_SETSIZE)
144 #define SLABZONE1_SIZE SLABZONE_SIZE(SLABZONE1_SETSIZE)
145 static uma_zone_t slabzones[2];
148 * The initial hash tables come out of this zone so they can be allocated
149 * prior to malloc coming up.
151 static uma_zone_t hashzone;
153 /* The boot-time adjusted value for cache line alignment. */
154 int uma_align_cache = 64 - 1;
156 static MALLOC_DEFINE(M_UMAHASH, "UMAHash", "UMA Hash Buckets");
157 static MALLOC_DEFINE(M_UMA, "UMA", "UMA Misc");
160 * Are we allowed to allocate buckets?
162 static int bucketdisable = 1;
164 /* Linked list of all kegs in the system */
165 static LIST_HEAD(,uma_keg) uma_kegs = LIST_HEAD_INITIALIZER(uma_kegs);
167 /* Linked list of all cache-only zones in the system */
168 static LIST_HEAD(,uma_zone) uma_cachezones =
169 LIST_HEAD_INITIALIZER(uma_cachezones);
172 * Mutex for global lists: uma_kegs, uma_cachezones, and the per-keg list of
175 static struct rwlock_padalign __exclusive_cache_line uma_rwlock;
177 static struct sx uma_reclaim_lock;
180 * First available virual address for boot time allocations.
182 static vm_offset_t bootstart;
183 static vm_offset_t bootmem;
186 * kmem soft limit, initialized by uma_set_limit(). Ensure that early
187 * allocations don't trigger a wakeup of the reclaim thread.
189 unsigned long uma_kmem_limit = LONG_MAX;
190 SYSCTL_ULONG(_vm, OID_AUTO, uma_kmem_limit, CTLFLAG_RD, &uma_kmem_limit, 0,
191 "UMA kernel memory soft limit");
192 unsigned long uma_kmem_total;
193 SYSCTL_ULONG(_vm, OID_AUTO, uma_kmem_total, CTLFLAG_RD, &uma_kmem_total, 0,
194 "UMA kernel memory usage");
196 /* Is the VM done starting up? */
203 } booted = BOOT_COLD;
206 * This is the handle used to schedule events that need to happen
207 * outside of the allocation fast path.
209 static struct callout uma_callout;
210 #define UMA_TIMEOUT 20 /* Seconds for callout interval. */
213 * This structure is passed as the zone ctor arg so that I don't have to create
214 * a special allocation function just for zones.
216 struct uma_zctor_args {
231 struct uma_kctor_args {
240 struct uma_bucket_zone {
242 const char *ubz_name;
243 int ubz_entries; /* Number of items it can hold. */
244 int ubz_maxsize; /* Maximum allocation size per-item. */
248 * Compute the actual number of bucket entries to pack them in power
249 * of two sizes for more efficient space utilization.
251 #define BUCKET_SIZE(n) \
252 (((sizeof(void *) * (n)) - sizeof(struct uma_bucket)) / sizeof(void *))
254 #define BUCKET_MAX BUCKET_SIZE(256)
256 struct uma_bucket_zone bucket_zones[] = {
257 /* Literal bucket sizes. */
258 { NULL, "2 Bucket", 2, 4096 },
259 { NULL, "4 Bucket", 4, 3072 },
260 { NULL, "8 Bucket", 8, 2048 },
261 { NULL, "16 Bucket", 16, 1024 },
262 /* Rounded down power of 2 sizes for efficiency. */
263 { NULL, "32 Bucket", BUCKET_SIZE(32), 512 },
264 { NULL, "64 Bucket", BUCKET_SIZE(64), 256 },
265 { NULL, "128 Bucket", BUCKET_SIZE(128), 128 },
266 { NULL, "256 Bucket", BUCKET_SIZE(256), 64 },
271 * Flags and enumerations to be passed to internal functions.
275 SKIP_CNT = 0x00000001,
276 SKIP_DTOR = 0x00010000,
277 SKIP_FINI = 0x00020000,
282 void uma_startup1(vm_offset_t);
283 void uma_startup2(void);
285 static void *noobj_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
286 static void *page_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
287 static void *pcpu_page_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
288 static void *startup_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
289 static void *contig_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
290 static void page_free(void *, vm_size_t, uint8_t);
291 static void pcpu_page_free(void *, vm_size_t, uint8_t);
292 static uma_slab_t keg_alloc_slab(uma_keg_t, uma_zone_t, int, int, int);
293 static void cache_drain(uma_zone_t);
294 static void bucket_drain(uma_zone_t, uma_bucket_t);
295 static void bucket_cache_reclaim(uma_zone_t zone, bool, int);
296 static bool bucket_cache_reclaim_domain(uma_zone_t, bool, bool, int);
297 static int keg_ctor(void *, int, void *, int);
298 static void keg_dtor(void *, int, void *);
299 static void keg_drain(uma_keg_t keg, int domain);
300 static int zone_ctor(void *, int, void *, int);
301 static void zone_dtor(void *, int, void *);
302 static inline void item_dtor(uma_zone_t zone, void *item, int size,
303 void *udata, enum zfreeskip skip);
304 static int zero_init(void *, int, int);
305 static void zone_free_bucket(uma_zone_t zone, uma_bucket_t bucket, void *udata,
306 int itemdomain, bool ws);
307 static void zone_foreach(void (*zfunc)(uma_zone_t, void *), void *);
308 static void zone_foreach_unlocked(void (*zfunc)(uma_zone_t, void *), void *);
309 static void zone_timeout(uma_zone_t zone, void *);
310 static int hash_alloc(struct uma_hash *, u_int);
311 static int hash_expand(struct uma_hash *, struct uma_hash *);
312 static void hash_free(struct uma_hash *hash);
313 static void uma_timeout(void *);
314 static void uma_shutdown(void);
315 static void *zone_alloc_item(uma_zone_t, void *, int, int);
316 static void zone_free_item(uma_zone_t, void *, void *, enum zfreeskip);
317 static int zone_alloc_limit(uma_zone_t zone, int count, int flags);
318 static void zone_free_limit(uma_zone_t zone, int count);
319 static void bucket_enable(void);
320 static void bucket_init(void);
321 static uma_bucket_t bucket_alloc(uma_zone_t zone, void *, int);
322 static void bucket_free(uma_zone_t zone, uma_bucket_t, void *);
323 static void bucket_zone_drain(int domain);
324 static uma_bucket_t zone_alloc_bucket(uma_zone_t, void *, int, int);
325 static void *slab_alloc_item(uma_keg_t keg, uma_slab_t slab);
326 static void slab_free_item(uma_zone_t zone, uma_slab_t slab, void *item);
327 static size_t slab_sizeof(int nitems);
328 static uma_keg_t uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit,
329 uma_fini fini, int align, uint32_t flags);
330 static int zone_import(void *, void **, int, int, int);
331 static void zone_release(void *, void **, int);
332 static bool cache_alloc(uma_zone_t, uma_cache_t, void *, int);
333 static bool cache_free(uma_zone_t, uma_cache_t, void *, void *, int);
335 static int sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS);
336 static int sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS);
337 static int sysctl_handle_uma_zone_allocs(SYSCTL_HANDLER_ARGS);
338 static int sysctl_handle_uma_zone_frees(SYSCTL_HANDLER_ARGS);
339 static int sysctl_handle_uma_zone_flags(SYSCTL_HANDLER_ARGS);
340 static int sysctl_handle_uma_slab_efficiency(SYSCTL_HANDLER_ARGS);
341 static int sysctl_handle_uma_zone_items(SYSCTL_HANDLER_ARGS);
343 static uint64_t uma_zone_get_allocs(uma_zone_t zone);
345 static SYSCTL_NODE(_vm, OID_AUTO, debug, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
346 "Memory allocation debugging");
349 static uint64_t uma_keg_get_allocs(uma_keg_t zone);
350 static inline struct noslabbits *slab_dbg_bits(uma_slab_t slab, uma_keg_t keg);
352 static bool uma_dbg_kskip(uma_keg_t keg, void *mem);
353 static bool uma_dbg_zskip(uma_zone_t zone, void *mem);
354 static void uma_dbg_free(uma_zone_t zone, uma_slab_t slab, void *item);
355 static void uma_dbg_alloc(uma_zone_t zone, uma_slab_t slab, void *item);
357 static u_int dbg_divisor = 1;
358 SYSCTL_UINT(_vm_debug, OID_AUTO, divisor,
359 CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &dbg_divisor, 0,
360 "Debug & thrash every this item in memory allocator");
362 static counter_u64_t uma_dbg_cnt = EARLY_COUNTER;
363 static counter_u64_t uma_skip_cnt = EARLY_COUNTER;
364 SYSCTL_COUNTER_U64(_vm_debug, OID_AUTO, trashed, CTLFLAG_RD,
365 &uma_dbg_cnt, "memory items debugged");
366 SYSCTL_COUNTER_U64(_vm_debug, OID_AUTO, skipped, CTLFLAG_RD,
367 &uma_skip_cnt, "memory items skipped, not debugged");
370 SYSCTL_NODE(_vm, OID_AUTO, uma, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
371 "Universal Memory Allocator");
373 SYSCTL_PROC(_vm, OID_AUTO, zone_count, CTLFLAG_RD|CTLFLAG_MPSAFE|CTLTYPE_INT,
374 0, 0, sysctl_vm_zone_count, "I", "Number of UMA zones");
376 SYSCTL_PROC(_vm, OID_AUTO, zone_stats, CTLFLAG_RD|CTLFLAG_MPSAFE|CTLTYPE_STRUCT,
377 0, 0, sysctl_vm_zone_stats, "s,struct uma_type_header", "Zone Stats");
379 static int zone_warnings = 1;
380 SYSCTL_INT(_vm, OID_AUTO, zone_warnings, CTLFLAG_RWTUN, &zone_warnings, 0,
381 "Warn when UMA zones becomes full");
383 static int multipage_slabs = 1;
384 TUNABLE_INT("vm.debug.uma_multipage_slabs", &multipage_slabs);
385 SYSCTL_INT(_vm_debug, OID_AUTO, uma_multipage_slabs,
386 CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &multipage_slabs, 0,
387 "UMA may choose larger slab sizes for better efficiency");
390 * Select the slab zone for an offpage slab with the given maximum item count.
392 static inline uma_zone_t
396 return (slabzones[ipers > SLABZONE0_SETSIZE]);
400 * This routine checks to see whether or not it's safe to enable buckets.
406 KASSERT(booted >= BOOT_KVA, ("Bucket enable before init"));
407 bucketdisable = vm_page_count_min();
411 * Initialize bucket_zones, the array of zones of buckets of various sizes.
413 * For each zone, calculate the memory required for each bucket, consisting
414 * of the header and an array of pointers.
419 struct uma_bucket_zone *ubz;
422 for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++) {
423 size = roundup(sizeof(struct uma_bucket), sizeof(void *));
424 size += sizeof(void *) * ubz->ubz_entries;
425 ubz->ubz_zone = uma_zcreate(ubz->ubz_name, size,
426 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR,
427 UMA_ZONE_MTXCLASS | UMA_ZFLAG_BUCKET |
428 UMA_ZONE_FIRSTTOUCH);
433 * Given a desired number of entries for a bucket, return the zone from which
434 * to allocate the bucket.
436 static struct uma_bucket_zone *
437 bucket_zone_lookup(int entries)
439 struct uma_bucket_zone *ubz;
441 for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++)
442 if (ubz->ubz_entries >= entries)
449 bucket_select(int size)
451 struct uma_bucket_zone *ubz;
453 ubz = &bucket_zones[0];
454 if (size > ubz->ubz_maxsize)
455 return MAX((ubz->ubz_maxsize * ubz->ubz_entries) / size, 1);
457 for (; ubz->ubz_entries != 0; ubz++)
458 if (ubz->ubz_maxsize < size)
461 return (ubz->ubz_entries);
465 bucket_alloc(uma_zone_t zone, void *udata, int flags)
467 struct uma_bucket_zone *ubz;
471 * Don't allocate buckets early in boot.
473 if (__predict_false(booted < BOOT_KVA))
477 * To limit bucket recursion we store the original zone flags
478 * in a cookie passed via zalloc_arg/zfree_arg. This allows the
479 * NOVM flag to persist even through deep recursions. We also
480 * store ZFLAG_BUCKET once we have recursed attempting to allocate
481 * a bucket for a bucket zone so we do not allow infinite bucket
482 * recursion. This cookie will even persist to frees of unused
483 * buckets via the allocation path or bucket allocations in the
486 if ((zone->uz_flags & UMA_ZFLAG_BUCKET) == 0)
487 udata = (void *)(uintptr_t)zone->uz_flags;
489 if ((uintptr_t)udata & UMA_ZFLAG_BUCKET)
491 udata = (void *)((uintptr_t)udata | UMA_ZFLAG_BUCKET);
493 if (((uintptr_t)udata & UMA_ZONE_VM) != 0)
495 ubz = bucket_zone_lookup(atomic_load_16(&zone->uz_bucket_size));
496 if (ubz->ubz_zone == zone && (ubz + 1)->ubz_entries != 0)
498 bucket = uma_zalloc_arg(ubz->ubz_zone, udata, flags);
501 bzero(bucket->ub_bucket, sizeof(void *) * ubz->ubz_entries);
504 bucket->ub_entries = min(ubz->ubz_entries,
505 zone->uz_bucket_size_max);
506 bucket->ub_seq = SMR_SEQ_INVALID;
507 CTR3(KTR_UMA, "bucket_alloc: zone %s(%p) allocated bucket %p",
508 zone->uz_name, zone, bucket);
515 bucket_free(uma_zone_t zone, uma_bucket_t bucket, void *udata)
517 struct uma_bucket_zone *ubz;
519 if (bucket->ub_cnt != 0)
520 bucket_drain(zone, bucket);
522 KASSERT(bucket->ub_cnt == 0,
523 ("bucket_free: Freeing a non free bucket."));
524 KASSERT(bucket->ub_seq == SMR_SEQ_INVALID,
525 ("bucket_free: Freeing an SMR bucket."));
526 if ((zone->uz_flags & UMA_ZFLAG_BUCKET) == 0)
527 udata = (void *)(uintptr_t)zone->uz_flags;
528 ubz = bucket_zone_lookup(bucket->ub_entries);
529 uma_zfree_arg(ubz->ubz_zone, bucket, udata);
533 bucket_zone_drain(int domain)
535 struct uma_bucket_zone *ubz;
537 for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++)
538 uma_zone_reclaim_domain(ubz->ubz_zone, UMA_RECLAIM_DRAIN,
543 _Static_assert(UMA_SMALLEST_UNIT % KASAN_SHADOW_SCALE == 0,
544 "Base UMA allocation size not a multiple of the KASAN scale factor");
547 kasan_mark_item_valid(uma_zone_t zone, void *item)
553 if ((zone->uz_flags & UMA_ZONE_NOKASAN) != 0)
557 rsz = roundup2(sz, KASAN_SHADOW_SCALE);
558 if ((zone->uz_flags & UMA_ZONE_PCPU) == 0) {
559 kasan_mark(item, sz, rsz, KASAN_GENERIC_REDZONE);
561 pcpu_item = zpcpu_base_to_offset(item);
562 for (i = 0; i <= mp_maxid; i++)
563 kasan_mark(zpcpu_get_cpu(pcpu_item, i), sz, rsz,
564 KASAN_GENERIC_REDZONE);
569 kasan_mark_item_invalid(uma_zone_t zone, void *item)
575 if ((zone->uz_flags & UMA_ZONE_NOKASAN) != 0)
578 sz = roundup2(zone->uz_size, KASAN_SHADOW_SCALE);
579 if ((zone->uz_flags & UMA_ZONE_PCPU) == 0) {
580 kasan_mark(item, 0, sz, KASAN_UMA_FREED);
582 pcpu_item = zpcpu_base_to_offset(item);
583 for (i = 0; i <= mp_maxid; i++)
584 kasan_mark(zpcpu_get_cpu(pcpu_item, i), 0, sz,
590 kasan_mark_slab_valid(uma_keg_t keg, void *mem)
594 if ((keg->uk_flags & UMA_ZONE_NOKASAN) == 0) {
595 sz = keg->uk_ppera * PAGE_SIZE;
596 kasan_mark(mem, sz, sz, 0);
601 kasan_mark_slab_invalid(uma_keg_t keg, void *mem)
605 if ((keg->uk_flags & UMA_ZONE_NOKASAN) == 0) {
606 if ((keg->uk_flags & UMA_ZFLAG_OFFPAGE) != 0)
607 sz = keg->uk_ppera * PAGE_SIZE;
610 kasan_mark(mem, 0, sz, KASAN_UMA_FREED);
615 kasan_mark_item_valid(uma_zone_t zone __unused, void *item __unused)
620 kasan_mark_item_invalid(uma_zone_t zone __unused, void *item __unused)
625 kasan_mark_slab_valid(uma_keg_t keg __unused, void *mem __unused)
630 kasan_mark_slab_invalid(uma_keg_t keg __unused, void *mem __unused)
636 * Acquire the domain lock and record contention.
638 static uma_zone_domain_t
639 zone_domain_lock(uma_zone_t zone, int domain)
641 uma_zone_domain_t zdom;
644 zdom = ZDOM_GET(zone, domain);
646 if (ZDOM_OWNED(zdom))
649 /* This is unsynchronized. The counter does not need to be precise. */
650 if (lockfail && zone->uz_bucket_size < zone->uz_bucket_size_max)
651 zone->uz_bucket_size++;
656 * Search for the domain with the least cached items and return it if it
657 * is out of balance with the preferred domain.
659 static __noinline int
660 zone_domain_lowest(uma_zone_t zone, int pref)
662 long least, nitems, prefitems;
666 prefitems = least = LONG_MAX;
668 for (i = 0; i < vm_ndomains; i++) {
669 nitems = ZDOM_GET(zone, i)->uzd_nitems;
670 if (nitems < least) {
677 if (prefitems < least * 2)
684 * Search for the domain with the most cached items and return it or the
685 * preferred domain if it has enough to proceed.
687 static __noinline int
688 zone_domain_highest(uma_zone_t zone, int pref)
694 if (ZDOM_GET(zone, pref)->uzd_nitems > BUCKET_MAX)
699 for (i = 0; i < vm_ndomains; i++) {
700 nitems = ZDOM_GET(zone, i)->uzd_nitems;
711 * Set the maximum imax value.
714 zone_domain_imax_set(uma_zone_domain_t zdom, int nitems)
718 old = zdom->uzd_imax;
722 } while (atomic_fcmpset_long(&zdom->uzd_imax, &old, nitems) == 0);
725 * We are at new maximum, so do the last WSS update for the old
726 * bimin and prepare to measure next allocation batch.
728 if (zdom->uzd_wss < old - zdom->uzd_bimin)
729 zdom->uzd_wss = old - zdom->uzd_bimin;
730 zdom->uzd_bimin = nitems;
734 * Attempt to satisfy an allocation by retrieving a full bucket from one of the
735 * zone's caches. If a bucket is found the zone is not locked on return.
738 zone_fetch_bucket(uma_zone_t zone, uma_zone_domain_t zdom, bool reclaim)
745 ZDOM_LOCK_ASSERT(zdom);
747 if ((bucket = STAILQ_FIRST(&zdom->uzd_buckets)) == NULL)
750 /* SMR Buckets can not be re-used until readers expire. */
751 if ((zone->uz_flags & UMA_ZONE_SMR) != 0 &&
752 bucket->ub_seq != SMR_SEQ_INVALID) {
753 if (!smr_poll(zone->uz_smr, bucket->ub_seq, false))
755 bucket->ub_seq = SMR_SEQ_INVALID;
756 dtor = (zone->uz_dtor != NULL) || UMA_ALWAYS_CTORDTOR;
757 if (STAILQ_NEXT(bucket, ub_link) != NULL)
758 zdom->uzd_seq = STAILQ_NEXT(bucket, ub_link)->ub_seq;
760 STAILQ_REMOVE_HEAD(&zdom->uzd_buckets, ub_link);
762 KASSERT(zdom->uzd_nitems >= bucket->ub_cnt,
763 ("%s: item count underflow (%ld, %d)",
764 __func__, zdom->uzd_nitems, bucket->ub_cnt));
765 KASSERT(bucket->ub_cnt > 0,
766 ("%s: empty bucket in bucket cache", __func__));
767 zdom->uzd_nitems -= bucket->ub_cnt;
771 * Shift the bounds of the current WSS interval to avoid
772 * perturbing the estimates.
774 cnt = lmin(zdom->uzd_bimin, bucket->ub_cnt);
775 atomic_subtract_long(&zdom->uzd_imax, cnt);
776 zdom->uzd_bimin -= cnt;
777 zdom->uzd_imin -= lmin(zdom->uzd_imin, bucket->ub_cnt);
778 if (zdom->uzd_limin >= bucket->ub_cnt) {
779 zdom->uzd_limin -= bucket->ub_cnt;
784 } else if (zdom->uzd_bimin > zdom->uzd_nitems) {
785 zdom->uzd_bimin = zdom->uzd_nitems;
786 if (zdom->uzd_imin > zdom->uzd_nitems)
787 zdom->uzd_imin = zdom->uzd_nitems;
792 for (i = 0; i < bucket->ub_cnt; i++)
793 item_dtor(zone, bucket->ub_bucket[i], zone->uz_size,
800 * Insert a full bucket into the specified cache. The "ws" parameter indicates
801 * whether the bucket's contents should be counted as part of the zone's working
802 * set. The bucket may be freed if it exceeds the bucket limit.
805 zone_put_bucket(uma_zone_t zone, int domain, uma_bucket_t bucket, void *udata,
808 uma_zone_domain_t zdom;
810 /* We don't cache empty buckets. This can happen after a reclaim. */
811 if (bucket->ub_cnt == 0)
813 zdom = zone_domain_lock(zone, domain);
816 * Conditionally set the maximum number of items.
818 zdom->uzd_nitems += bucket->ub_cnt;
819 if (__predict_true(zdom->uzd_nitems < zone->uz_bucket_max)) {
821 zone_domain_imax_set(zdom, zdom->uzd_nitems);
824 * Shift the bounds of the current WSS interval to
825 * avoid perturbing the estimates.
827 atomic_add_long(&zdom->uzd_imax, bucket->ub_cnt);
828 zdom->uzd_imin += bucket->ub_cnt;
829 zdom->uzd_bimin += bucket->ub_cnt;
830 zdom->uzd_limin += bucket->ub_cnt;
832 if (STAILQ_EMPTY(&zdom->uzd_buckets))
833 zdom->uzd_seq = bucket->ub_seq;
836 * Try to promote reuse of recently used items. For items
837 * protected by SMR, try to defer reuse to minimize polling.
839 if (bucket->ub_seq == SMR_SEQ_INVALID)
840 STAILQ_INSERT_HEAD(&zdom->uzd_buckets, bucket, ub_link);
842 STAILQ_INSERT_TAIL(&zdom->uzd_buckets, bucket, ub_link);
846 zdom->uzd_nitems -= bucket->ub_cnt;
849 bucket_free(zone, bucket, udata);
852 /* Pops an item out of a per-cpu cache bucket. */
854 cache_bucket_pop(uma_cache_t cache, uma_cache_bucket_t bucket)
858 CRITICAL_ASSERT(curthread);
861 item = bucket->ucb_bucket->ub_bucket[bucket->ucb_cnt];
863 bucket->ucb_bucket->ub_bucket[bucket->ucb_cnt] = NULL;
864 KASSERT(item != NULL, ("uma_zalloc: Bucket pointer mangled."));
871 /* Pushes an item into a per-cpu cache bucket. */
873 cache_bucket_push(uma_cache_t cache, uma_cache_bucket_t bucket, void *item)
876 CRITICAL_ASSERT(curthread);
877 KASSERT(bucket->ucb_bucket->ub_bucket[bucket->ucb_cnt] == NULL,
878 ("uma_zfree: Freeing to non free bucket index."));
880 bucket->ucb_bucket->ub_bucket[bucket->ucb_cnt] = item;
886 * Unload a UMA bucket from a per-cpu cache.
888 static inline uma_bucket_t
889 cache_bucket_unload(uma_cache_bucket_t bucket)
893 b = bucket->ucb_bucket;
895 MPASS(b->ub_entries == bucket->ucb_entries);
896 b->ub_cnt = bucket->ucb_cnt;
897 bucket->ucb_bucket = NULL;
898 bucket->ucb_entries = bucket->ucb_cnt = 0;
904 static inline uma_bucket_t
905 cache_bucket_unload_alloc(uma_cache_t cache)
908 return (cache_bucket_unload(&cache->uc_allocbucket));
911 static inline uma_bucket_t
912 cache_bucket_unload_free(uma_cache_t cache)
915 return (cache_bucket_unload(&cache->uc_freebucket));
918 static inline uma_bucket_t
919 cache_bucket_unload_cross(uma_cache_t cache)
922 return (cache_bucket_unload(&cache->uc_crossbucket));
926 * Load a bucket into a per-cpu cache bucket.
929 cache_bucket_load(uma_cache_bucket_t bucket, uma_bucket_t b)
932 CRITICAL_ASSERT(curthread);
933 MPASS(bucket->ucb_bucket == NULL);
934 MPASS(b->ub_seq == SMR_SEQ_INVALID);
936 bucket->ucb_bucket = b;
937 bucket->ucb_cnt = b->ub_cnt;
938 bucket->ucb_entries = b->ub_entries;
942 cache_bucket_load_alloc(uma_cache_t cache, uma_bucket_t b)
945 cache_bucket_load(&cache->uc_allocbucket, b);
949 cache_bucket_load_free(uma_cache_t cache, uma_bucket_t b)
952 cache_bucket_load(&cache->uc_freebucket, b);
957 cache_bucket_load_cross(uma_cache_t cache, uma_bucket_t b)
960 cache_bucket_load(&cache->uc_crossbucket, b);
965 * Copy and preserve ucb_spare.
968 cache_bucket_copy(uma_cache_bucket_t b1, uma_cache_bucket_t b2)
971 b1->ucb_bucket = b2->ucb_bucket;
972 b1->ucb_entries = b2->ucb_entries;
973 b1->ucb_cnt = b2->ucb_cnt;
977 * Swap two cache buckets.
980 cache_bucket_swap(uma_cache_bucket_t b1, uma_cache_bucket_t b2)
982 struct uma_cache_bucket b3;
984 CRITICAL_ASSERT(curthread);
986 cache_bucket_copy(&b3, b1);
987 cache_bucket_copy(b1, b2);
988 cache_bucket_copy(b2, &b3);
992 * Attempt to fetch a bucket from a zone on behalf of the current cpu cache.
995 cache_fetch_bucket(uma_zone_t zone, uma_cache_t cache, int domain)
997 uma_zone_domain_t zdom;
1002 * Avoid the lock if possible.
1004 zdom = ZDOM_GET(zone, domain);
1005 if (zdom->uzd_nitems == 0)
1008 if ((cache_uz_flags(cache) & UMA_ZONE_SMR) != 0 &&
1009 (seq = atomic_load_32(&zdom->uzd_seq)) != SMR_SEQ_INVALID &&
1010 !smr_poll(zone->uz_smr, seq, false))
1014 * Check the zone's cache of buckets.
1016 zdom = zone_domain_lock(zone, domain);
1017 if ((bucket = zone_fetch_bucket(zone, zdom, false)) != NULL)
1025 zone_log_warning(uma_zone_t zone)
1027 static const struct timeval warninterval = { 300, 0 };
1029 if (!zone_warnings || zone->uz_warning == NULL)
1032 if (ratecheck(&zone->uz_ratecheck, &warninterval))
1033 printf("[zone: %s] %s\n", zone->uz_name, zone->uz_warning);
1037 zone_maxaction(uma_zone_t zone)
1040 if (zone->uz_maxaction.ta_func != NULL)
1041 taskqueue_enqueue(taskqueue_thread, &zone->uz_maxaction);
1045 * Routine called by timeout which is used to fire off some time interval
1046 * based calculations. (stats, hash size, etc.)
1055 uma_timeout(void *unused)
1058 zone_foreach(zone_timeout, NULL);
1060 /* Reschedule this event */
1061 callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL);
1065 * Update the working set size estimates for the zone's bucket cache.
1066 * The constants chosen here are somewhat arbitrary.
1069 zone_domain_update_wss(uma_zone_domain_t zdom)
1073 ZDOM_LOCK_ASSERT(zdom);
1074 MPASS(zdom->uzd_imax >= zdom->uzd_nitems);
1075 MPASS(zdom->uzd_nitems >= zdom->uzd_bimin);
1076 MPASS(zdom->uzd_bimin >= zdom->uzd_imin);
1079 * Estimate WSS as modified moving average of biggest allocation
1080 * batches for each period over few minutes (UMA_TIMEOUT of 20s).
1082 zdom->uzd_wss = lmax(zdom->uzd_wss * 3 / 4,
1083 zdom->uzd_imax - zdom->uzd_bimin);
1086 * Estimate longtime minimum item count as a combination of recent
1087 * minimum item count, adjusted by WSS for safety, and the modified
1088 * moving average over the last several hours (UMA_TIMEOUT of 20s).
1089 * timin measures time since limin tried to go negative, that means
1090 * we were dangerously close to or got out of cache.
1092 m = zdom->uzd_imin - zdom->uzd_wss;
1094 if (zdom->uzd_limin >= m)
1095 zdom->uzd_limin = m;
1097 zdom->uzd_limin = (m + zdom->uzd_limin * 255) / 256;
1100 zdom->uzd_limin = 0;
1101 zdom->uzd_timin = 0;
1104 /* To reduce period edge effects on WSS keep half of the imax. */
1105 atomic_subtract_long(&zdom->uzd_imax,
1106 (zdom->uzd_imax - zdom->uzd_nitems + 1) / 2);
1107 zdom->uzd_imin = zdom->uzd_bimin = zdom->uzd_nitems;
1111 * Routine to perform timeout driven calculations. This expands the
1112 * hashes and does per cpu statistics aggregation.
1117 zone_timeout(uma_zone_t zone, void *unused)
1122 if ((zone->uz_flags & UMA_ZFLAG_HASH) == 0)
1128 * Hash zones are non-numa by definition so the first domain
1129 * is the only one present.
1132 pages = keg->uk_domain[0].ud_pages;
1135 * Expand the keg hash table.
1137 * This is done if the number of slabs is larger than the hash size.
1138 * What I'm trying to do here is completely reduce collisions. This
1139 * may be a little aggressive. Should I allow for two collisions max?
1141 if ((slabs = pages / keg->uk_ppera) > keg->uk_hash.uh_hashsize) {
1142 struct uma_hash newhash;
1143 struct uma_hash oldhash;
1147 * This is so involved because allocating and freeing
1148 * while the keg lock is held will lead to deadlock.
1149 * I have to do everything in stages and check for
1153 ret = hash_alloc(&newhash, 1 << fls(slabs));
1156 if (hash_expand(&keg->uk_hash, &newhash)) {
1157 oldhash = keg->uk_hash;
1158 keg->uk_hash = newhash;
1163 hash_free(&oldhash);
1170 /* Trim caches not used for a long time. */
1171 for (int i = 0; i < vm_ndomains; i++) {
1172 if (bucket_cache_reclaim_domain(zone, false, false, i) &&
1173 (zone->uz_flags & UMA_ZFLAG_CACHE) == 0)
1174 keg_drain(zone->uz_keg, i);
1179 * Allocate and zero fill the next sized hash table from the appropriate
1183 * hash A new hash structure with the old hash size in uh_hashsize
1186 * 1 on success and 0 on failure.
1189 hash_alloc(struct uma_hash *hash, u_int size)
1193 KASSERT(powerof2(size), ("hash size must be power of 2"));
1194 if (size > UMA_HASH_SIZE_INIT) {
1195 hash->uh_hashsize = size;
1196 alloc = sizeof(hash->uh_slab_hash[0]) * hash->uh_hashsize;
1197 hash->uh_slab_hash = malloc(alloc, M_UMAHASH, M_NOWAIT);
1199 alloc = sizeof(hash->uh_slab_hash[0]) * UMA_HASH_SIZE_INIT;
1200 hash->uh_slab_hash = zone_alloc_item(hashzone, NULL,
1201 UMA_ANYDOMAIN, M_WAITOK);
1202 hash->uh_hashsize = UMA_HASH_SIZE_INIT;
1204 if (hash->uh_slab_hash) {
1205 bzero(hash->uh_slab_hash, alloc);
1206 hash->uh_hashmask = hash->uh_hashsize - 1;
1214 * Expands the hash table for HASH zones. This is done from zone_timeout
1215 * to reduce collisions. This must not be done in the regular allocation
1216 * path, otherwise, we can recurse on the vm while allocating pages.
1219 * oldhash The hash you want to expand
1220 * newhash The hash structure for the new table
1228 hash_expand(struct uma_hash *oldhash, struct uma_hash *newhash)
1230 uma_hash_slab_t slab;
1234 if (!newhash->uh_slab_hash)
1237 if (oldhash->uh_hashsize >= newhash->uh_hashsize)
1241 * I need to investigate hash algorithms for resizing without a
1245 for (idx = 0; idx < oldhash->uh_hashsize; idx++)
1246 while (!LIST_EMPTY(&oldhash->uh_slab_hash[idx])) {
1247 slab = LIST_FIRST(&oldhash->uh_slab_hash[idx]);
1248 LIST_REMOVE(slab, uhs_hlink);
1249 hval = UMA_HASH(newhash, slab->uhs_data);
1250 LIST_INSERT_HEAD(&newhash->uh_slab_hash[hval],
1258 * Free the hash bucket to the appropriate backing store.
1261 * slab_hash The hash bucket we're freeing
1262 * hashsize The number of entries in that hash bucket
1268 hash_free(struct uma_hash *hash)
1270 if (hash->uh_slab_hash == NULL)
1272 if (hash->uh_hashsize == UMA_HASH_SIZE_INIT)
1273 zone_free_item(hashzone, hash->uh_slab_hash, NULL, SKIP_NONE);
1275 free(hash->uh_slab_hash, M_UMAHASH);
1279 * Frees all outstanding items in a bucket
1282 * zone The zone to free to, must be unlocked.
1283 * bucket The free/alloc bucket with items.
1289 bucket_drain(uma_zone_t zone, uma_bucket_t bucket)
1293 if (bucket->ub_cnt == 0)
1296 if ((zone->uz_flags & UMA_ZONE_SMR) != 0 &&
1297 bucket->ub_seq != SMR_SEQ_INVALID) {
1298 smr_wait(zone->uz_smr, bucket->ub_seq);
1299 bucket->ub_seq = SMR_SEQ_INVALID;
1300 for (i = 0; i < bucket->ub_cnt; i++)
1301 item_dtor(zone, bucket->ub_bucket[i],
1302 zone->uz_size, NULL, SKIP_NONE);
1305 for (i = 0; i < bucket->ub_cnt; i++) {
1306 kasan_mark_item_valid(zone, bucket->ub_bucket[i]);
1307 zone->uz_fini(bucket->ub_bucket[i], zone->uz_size);
1308 kasan_mark_item_invalid(zone, bucket->ub_bucket[i]);
1310 zone->uz_release(zone->uz_arg, bucket->ub_bucket, bucket->ub_cnt);
1311 if (zone->uz_max_items > 0)
1312 zone_free_limit(zone, bucket->ub_cnt);
1314 bzero(bucket->ub_bucket, sizeof(void *) * bucket->ub_cnt);
1320 * Drains the per cpu caches for a zone.
1322 * NOTE: This may only be called while the zone is being torn down, and not
1323 * during normal operation. This is necessary in order that we do not have
1324 * to migrate CPUs to drain the per-CPU caches.
1327 * zone The zone to drain, must be unlocked.
1333 cache_drain(uma_zone_t zone)
1336 uma_bucket_t bucket;
1341 * XXX: It is safe to not lock the per-CPU caches, because we're
1342 * tearing down the zone anyway. I.e., there will be no further use
1343 * of the caches at this point.
1345 * XXX: It would good to be able to assert that the zone is being
1346 * torn down to prevent improper use of cache_drain().
1348 seq = SMR_SEQ_INVALID;
1349 if ((zone->uz_flags & UMA_ZONE_SMR) != 0)
1350 seq = smr_advance(zone->uz_smr);
1352 cache = &zone->uz_cpu[cpu];
1353 bucket = cache_bucket_unload_alloc(cache);
1355 bucket_free(zone, bucket, NULL);
1356 bucket = cache_bucket_unload_free(cache);
1357 if (bucket != NULL) {
1358 bucket->ub_seq = seq;
1359 bucket_free(zone, bucket, NULL);
1361 bucket = cache_bucket_unload_cross(cache);
1362 if (bucket != NULL) {
1363 bucket->ub_seq = seq;
1364 bucket_free(zone, bucket, NULL);
1367 bucket_cache_reclaim(zone, true, UMA_ANYDOMAIN);
1371 cache_shrink(uma_zone_t zone, void *unused)
1374 if (zone->uz_flags & UMA_ZFLAG_INTERNAL)
1378 zone->uz_bucket_size =
1379 (zone->uz_bucket_size_min + zone->uz_bucket_size) / 2;
1384 cache_drain_safe_cpu(uma_zone_t zone, void *unused)
1387 uma_bucket_t b1, b2, b3;
1390 if (zone->uz_flags & UMA_ZFLAG_INTERNAL)
1393 b1 = b2 = b3 = NULL;
1395 cache = &zone->uz_cpu[curcpu];
1396 domain = PCPU_GET(domain);
1397 b1 = cache_bucket_unload_alloc(cache);
1400 * Don't flush SMR zone buckets. This leaves the zone without a
1401 * bucket and forces every free to synchronize().
1403 if ((zone->uz_flags & UMA_ZONE_SMR) == 0) {
1404 b2 = cache_bucket_unload_free(cache);
1405 b3 = cache_bucket_unload_cross(cache);
1410 zone_free_bucket(zone, b1, NULL, domain, false);
1412 zone_free_bucket(zone, b2, NULL, domain, false);
1414 /* Adjust the domain so it goes to zone_free_cross. */
1415 domain = (domain + 1) % vm_ndomains;
1416 zone_free_bucket(zone, b3, NULL, domain, false);
1421 * Safely drain per-CPU caches of a zone(s) to alloc bucket.
1422 * This is an expensive call because it needs to bind to all CPUs
1423 * one by one and enter a critical section on each of them in order
1424 * to safely access their cache buckets.
1425 * Zone lock must not be held on call this function.
1428 pcpu_cache_drain_safe(uma_zone_t zone)
1433 * Polite bucket sizes shrinking was not enough, shrink aggressively.
1436 cache_shrink(zone, NULL);
1438 zone_foreach(cache_shrink, NULL);
1441 thread_lock(curthread);
1442 sched_bind(curthread, cpu);
1443 thread_unlock(curthread);
1446 cache_drain_safe_cpu(zone, NULL);
1448 zone_foreach(cache_drain_safe_cpu, NULL);
1450 thread_lock(curthread);
1451 sched_unbind(curthread);
1452 thread_unlock(curthread);
1456 * Reclaim cached buckets from a zone. All buckets are reclaimed if the caller
1457 * requested a drain, otherwise the per-domain caches are trimmed to either
1458 * estimated working set size.
1461 bucket_cache_reclaim_domain(uma_zone_t zone, bool drain, bool trim, int domain)
1463 uma_zone_domain_t zdom;
1464 uma_bucket_t bucket;
1469 * The cross bucket is partially filled and not part of
1470 * the item count. Reclaim it individually here.
1472 zdom = ZDOM_GET(zone, domain);
1473 if ((zone->uz_flags & UMA_ZONE_SMR) == 0 || drain) {
1474 ZONE_CROSS_LOCK(zone);
1475 bucket = zdom->uzd_cross;
1476 zdom->uzd_cross = NULL;
1477 ZONE_CROSS_UNLOCK(zone);
1479 bucket_free(zone, bucket, NULL);
1483 * If we were asked to drain the zone, we are done only once
1484 * this bucket cache is empty. If trim, we reclaim items in
1485 * excess of the zone's estimated working set size. Multiple
1486 * consecutive calls will shrink the WSS and so reclaim more.
1487 * If neither drain nor trim, then voluntarily reclaim 1/4
1488 * (to reduce first spike) of items not used for a long time.
1491 zone_domain_update_wss(zdom);
1495 target = zdom->uzd_wss;
1496 else if (zdom->uzd_timin > 900 / UMA_TIMEOUT)
1497 target = zdom->uzd_nitems - zdom->uzd_limin / 4;
1502 while ((bucket = STAILQ_FIRST(&zdom->uzd_buckets)) != NULL &&
1503 zdom->uzd_nitems >= target + bucket->ub_cnt) {
1504 bucket = zone_fetch_bucket(zone, zdom, true);
1507 bucket_free(zone, bucket, NULL);
1516 bucket_cache_reclaim(uma_zone_t zone, bool drain, int domain)
1521 * Shrink the zone bucket size to ensure that the per-CPU caches
1522 * don't grow too large.
1524 if (zone->uz_bucket_size > zone->uz_bucket_size_min)
1525 zone->uz_bucket_size--;
1527 if (domain != UMA_ANYDOMAIN &&
1528 (zone->uz_flags & UMA_ZONE_ROUNDROBIN) == 0) {
1529 bucket_cache_reclaim_domain(zone, drain, true, domain);
1531 for (i = 0; i < vm_ndomains; i++)
1532 bucket_cache_reclaim_domain(zone, drain, true, i);
1537 keg_free_slab(uma_keg_t keg, uma_slab_t slab, int start)
1544 CTR4(KTR_UMA, "keg_free_slab keg %s(%p) slab %p, returning %d bytes",
1545 keg->uk_name, keg, slab, PAGE_SIZE * keg->uk_ppera);
1547 mem = slab_data(slab, keg);
1548 size = PAGE_SIZE * keg->uk_ppera;
1550 kasan_mark_slab_valid(keg, mem);
1551 if (keg->uk_fini != NULL) {
1552 for (i = start - 1; i > -1; i--)
1555 * trash_fini implies that dtor was trash_dtor. trash_fini
1556 * would check that memory hasn't been modified since free,
1557 * which executed trash_dtor.
1558 * That's why we need to run uma_dbg_kskip() check here,
1559 * albeit we don't make skip check for other init/fini
1562 if (!uma_dbg_kskip(keg, slab_item(slab, keg, i)) ||
1563 keg->uk_fini != trash_fini)
1565 keg->uk_fini(slab_item(slab, keg, i), keg->uk_size);
1567 flags = slab->us_flags;
1568 if (keg->uk_flags & UMA_ZFLAG_OFFPAGE) {
1569 zone_free_item(slabzone(keg->uk_ipers), slab_tohashslab(slab),
1572 keg->uk_freef(mem, size, flags);
1573 uma_total_dec(size);
1577 keg_drain_domain(uma_keg_t keg, int domain)
1579 struct slabhead freeslabs;
1581 uma_slab_t slab, tmp;
1582 uint32_t i, stofree, stokeep, partial;
1584 dom = &keg->uk_domain[domain];
1585 LIST_INIT(&freeslabs);
1587 CTR4(KTR_UMA, "keg_drain %s(%p) domain %d free items: %u",
1588 keg->uk_name, keg, domain, dom->ud_free_items);
1590 KEG_LOCK(keg, domain);
1593 * Are the free items in partially allocated slabs sufficient to meet
1594 * the reserve? If not, compute the number of fully free slabs that must
1597 partial = dom->ud_free_items - dom->ud_free_slabs * keg->uk_ipers;
1598 if (partial < keg->uk_reserve) {
1599 stokeep = min(dom->ud_free_slabs,
1600 howmany(keg->uk_reserve - partial, keg->uk_ipers));
1604 stofree = dom->ud_free_slabs - stokeep;
1607 * Partition the free slabs into two sets: those that must be kept in
1608 * order to maintain the reserve, and those that may be released back to
1609 * the system. Since one set may be much larger than the other,
1610 * populate the smaller of the two sets and swap them if necessary.
1612 for (i = min(stofree, stokeep); i > 0; i--) {
1613 slab = LIST_FIRST(&dom->ud_free_slab);
1614 LIST_REMOVE(slab, us_link);
1615 LIST_INSERT_HEAD(&freeslabs, slab, us_link);
1617 if (stofree > stokeep)
1618 LIST_SWAP(&freeslabs, &dom->ud_free_slab, uma_slab, us_link);
1620 if ((keg->uk_flags & UMA_ZFLAG_HASH) != 0) {
1621 LIST_FOREACH(slab, &freeslabs, us_link)
1622 UMA_HASH_REMOVE(&keg->uk_hash, slab);
1624 dom->ud_free_items -= stofree * keg->uk_ipers;
1625 dom->ud_free_slabs -= stofree;
1626 dom->ud_pages -= stofree * keg->uk_ppera;
1627 KEG_UNLOCK(keg, domain);
1629 LIST_FOREACH_SAFE(slab, &freeslabs, us_link, tmp)
1630 keg_free_slab(keg, slab, keg->uk_ipers);
1634 * Frees pages from a keg back to the system. This is done on demand from
1635 * the pageout daemon.
1640 keg_drain(uma_keg_t keg, int domain)
1644 if ((keg->uk_flags & UMA_ZONE_NOFREE) != 0)
1646 if (domain != UMA_ANYDOMAIN) {
1647 keg_drain_domain(keg, domain);
1649 for (i = 0; i < vm_ndomains; i++)
1650 keg_drain_domain(keg, i);
1655 zone_reclaim(uma_zone_t zone, int domain, int waitok, bool drain)
1658 * Count active reclaim operations in order to interlock with
1659 * zone_dtor(), which removes the zone from global lists before
1660 * attempting to reclaim items itself.
1662 * The zone may be destroyed while sleeping, so only zone_dtor() should
1666 if (waitok == M_WAITOK) {
1667 while (zone->uz_reclaimers > 0)
1668 msleep(zone, ZONE_LOCKPTR(zone), PVM, "zonedrain", 1);
1670 zone->uz_reclaimers++;
1672 bucket_cache_reclaim(zone, drain, domain);
1674 if ((zone->uz_flags & UMA_ZFLAG_CACHE) == 0)
1675 keg_drain(zone->uz_keg, domain);
1677 zone->uz_reclaimers--;
1678 if (zone->uz_reclaimers == 0)
1684 zone_drain(uma_zone_t zone, void *arg)
1688 domain = (int)(uintptr_t)arg;
1689 zone_reclaim(zone, domain, M_NOWAIT, true);
1693 zone_trim(uma_zone_t zone, void *arg)
1697 domain = (int)(uintptr_t)arg;
1698 zone_reclaim(zone, domain, M_NOWAIT, false);
1702 * Allocate a new slab for a keg and inserts it into the partial slab list.
1703 * The keg should be unlocked on entry. If the allocation succeeds it will
1704 * be locked on return.
1707 * flags Wait flags for the item initialization routine
1708 * aflags Wait flags for the slab allocation
1711 * The slab that was allocated or NULL if there is no memory and the
1712 * caller specified M_NOWAIT.
1715 keg_alloc_slab(uma_keg_t keg, uma_zone_t zone, int domain, int flags,
1725 KASSERT(domain >= 0 && domain < vm_ndomains,
1726 ("keg_alloc_slab: domain %d out of range", domain));
1730 if (keg->uk_flags & UMA_ZFLAG_OFFPAGE) {
1731 uma_hash_slab_t hslab;
1732 hslab = zone_alloc_item(slabzone(keg->uk_ipers), NULL,
1736 slab = &hslab->uhs_slab;
1740 * This reproduces the old vm_zone behavior of zero filling pages the
1741 * first time they are added to a zone.
1743 * Malloced items are zeroed in uma_zalloc.
1746 if ((keg->uk_flags & UMA_ZONE_MALLOC) == 0)
1751 if (keg->uk_flags & UMA_ZONE_NODUMP)
1754 /* zone is passed for legacy reasons. */
1755 size = keg->uk_ppera * PAGE_SIZE;
1756 mem = keg->uk_allocf(zone, size, domain, &sflags, aflags);
1758 if (keg->uk_flags & UMA_ZFLAG_OFFPAGE)
1759 zone_free_item(slabzone(keg->uk_ipers),
1760 slab_tohashslab(slab), NULL, SKIP_NONE);
1763 uma_total_inc(size);
1765 /* For HASH zones all pages go to the same uma_domain. */
1766 if ((keg->uk_flags & UMA_ZFLAG_HASH) != 0)
1769 /* Point the slab into the allocated memory */
1770 if (!(keg->uk_flags & UMA_ZFLAG_OFFPAGE))
1771 slab = (uma_slab_t)(mem + keg->uk_pgoff);
1773 slab_tohashslab(slab)->uhs_data = mem;
1775 if (keg->uk_flags & UMA_ZFLAG_VTOSLAB)
1776 for (i = 0; i < keg->uk_ppera; i++)
1777 vsetzoneslab((vm_offset_t)mem + (i * PAGE_SIZE),
1780 slab->us_freecount = keg->uk_ipers;
1781 slab->us_flags = sflags;
1782 slab->us_domain = domain;
1784 BIT_FILL(keg->uk_ipers, &slab->us_free);
1786 BIT_ZERO(keg->uk_ipers, slab_dbg_bits(slab, keg));
1789 if (keg->uk_init != NULL) {
1790 for (i = 0; i < keg->uk_ipers; i++)
1791 if (keg->uk_init(slab_item(slab, keg, i),
1792 keg->uk_size, flags) != 0)
1794 if (i != keg->uk_ipers) {
1795 keg_free_slab(keg, slab, i);
1799 kasan_mark_slab_invalid(keg, mem);
1800 KEG_LOCK(keg, domain);
1802 CTR3(KTR_UMA, "keg_alloc_slab: allocated slab %p for %s(%p)",
1803 slab, keg->uk_name, keg);
1805 if (keg->uk_flags & UMA_ZFLAG_HASH)
1806 UMA_HASH_INSERT(&keg->uk_hash, slab, mem);
1809 * If we got a slab here it's safe to mark it partially used
1810 * and return. We assume that the caller is going to remove
1811 * at least one item.
1813 dom = &keg->uk_domain[domain];
1814 LIST_INSERT_HEAD(&dom->ud_part_slab, slab, us_link);
1815 dom->ud_pages += keg->uk_ppera;
1816 dom->ud_free_items += keg->uk_ipers;
1825 * This function is intended to be used early on in place of page_alloc(). It
1826 * performs contiguous physical memory allocations and uses a bump allocator for
1827 * KVA, so is usable before the kernel map is initialized.
1830 startup_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
1837 pages = howmany(bytes, PAGE_SIZE);
1838 KASSERT(pages > 0, ("%s can't reserve 0 pages", __func__));
1840 *pflag = UMA_SLAB_BOOT;
1841 m = vm_page_alloc_noobj_contig_domain(domain, malloc2vm_flags(wait) |
1842 VM_ALLOC_WIRED, pages, (vm_paddr_t)0, ~(vm_paddr_t)0, 1, 0,
1843 VM_MEMATTR_DEFAULT);
1847 pa = VM_PAGE_TO_PHYS(m);
1848 for (i = 0; i < pages; i++, pa += PAGE_SIZE) {
1849 #if defined(__aarch64__) || defined(__amd64__) || defined(__mips__) || \
1850 defined(__riscv) || defined(__powerpc64__)
1851 if ((wait & M_NODUMP) == 0)
1856 /* Allocate KVA and indirectly advance bootmem. */
1857 return ((void *)pmap_map(&bootmem, m->phys_addr,
1858 m->phys_addr + (pages * PAGE_SIZE), VM_PROT_READ | VM_PROT_WRITE));
1862 startup_free(void *mem, vm_size_t bytes)
1867 va = (vm_offset_t)mem;
1868 m = PHYS_TO_VM_PAGE(pmap_kextract(va));
1871 * startup_alloc() returns direct-mapped slabs on some platforms. Avoid
1872 * unmapping ranges of the direct map.
1874 if (va >= bootstart && va + bytes <= bootmem)
1875 pmap_remove(kernel_pmap, va, va + bytes);
1876 for (; bytes != 0; bytes -= PAGE_SIZE, m++) {
1877 #if defined(__aarch64__) || defined(__amd64__) || defined(__mips__) || \
1878 defined(__riscv) || defined(__powerpc64__)
1879 dump_drop_page(VM_PAGE_TO_PHYS(m));
1881 vm_page_unwire_noq(m);
1887 * Allocates a number of pages from the system
1890 * bytes The number of bytes requested
1891 * wait Shall we wait?
1894 * A pointer to the alloced memory or possibly
1895 * NULL if M_NOWAIT is set.
1898 page_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
1901 void *p; /* Returned page */
1903 *pflag = UMA_SLAB_KERNEL;
1904 p = (void *)kmem_malloc_domainset(DOMAINSET_FIXED(domain), bytes, wait);
1910 pcpu_page_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
1913 struct pglist alloctail;
1914 vm_offset_t addr, zkva;
1916 vm_page_t p, p_next;
1921 MPASS(bytes == (mp_maxid + 1) * PAGE_SIZE);
1923 TAILQ_INIT(&alloctail);
1924 flags = VM_ALLOC_SYSTEM | VM_ALLOC_WIRED | malloc2vm_flags(wait);
1925 *pflag = UMA_SLAB_KERNEL;
1926 for (cpu = 0; cpu <= mp_maxid; cpu++) {
1927 if (CPU_ABSENT(cpu)) {
1928 p = vm_page_alloc_noobj(flags);
1931 p = vm_page_alloc_noobj(flags);
1933 pc = pcpu_find(cpu);
1934 if (__predict_false(VM_DOMAIN_EMPTY(pc->pc_domain)))
1937 p = vm_page_alloc_noobj_domain(pc->pc_domain,
1939 if (__predict_false(p == NULL))
1940 p = vm_page_alloc_noobj(flags);
1943 if (__predict_false(p == NULL))
1945 TAILQ_INSERT_TAIL(&alloctail, p, listq);
1947 if ((addr = kva_alloc(bytes)) == 0)
1950 TAILQ_FOREACH(p, &alloctail, listq) {
1951 pmap_qenter(zkva, &p, 1);
1954 return ((void*)addr);
1956 TAILQ_FOREACH_SAFE(p, &alloctail, listq, p_next) {
1957 vm_page_unwire_noq(p);
1964 * Allocates a number of pages from within an object
1967 * bytes The number of bytes requested
1968 * wait Shall we wait?
1971 * A pointer to the alloced memory or possibly
1972 * NULL if M_NOWAIT is set.
1975 noobj_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *flags,
1978 TAILQ_HEAD(, vm_page) alloctail;
1980 vm_offset_t retkva, zkva;
1981 vm_page_t p, p_next;
1985 TAILQ_INIT(&alloctail);
1987 req = VM_ALLOC_INTERRUPT | VM_ALLOC_WIRED;
1988 if ((wait & M_WAITOK) != 0)
1989 req |= VM_ALLOC_WAITOK;
1991 npages = howmany(bytes, PAGE_SIZE);
1992 while (npages > 0) {
1993 p = vm_page_alloc_noobj_domain(domain, req);
1996 * Since the page does not belong to an object, its
1999 TAILQ_INSERT_TAIL(&alloctail, p, listq);
2004 * Page allocation failed, free intermediate pages and
2007 TAILQ_FOREACH_SAFE(p, &alloctail, listq, p_next) {
2008 vm_page_unwire_noq(p);
2013 *flags = UMA_SLAB_PRIV;
2014 zkva = keg->uk_kva +
2015 atomic_fetchadd_long(&keg->uk_offset, round_page(bytes));
2017 TAILQ_FOREACH(p, &alloctail, listq) {
2018 pmap_qenter(zkva, &p, 1);
2022 return ((void *)retkva);
2026 * Allocate physically contiguous pages.
2029 contig_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
2033 *pflag = UMA_SLAB_KERNEL;
2034 return ((void *)kmem_alloc_contig_domainset(DOMAINSET_FIXED(domain),
2035 bytes, wait, 0, ~(vm_paddr_t)0, 1, 0, VM_MEMATTR_DEFAULT));
2039 * Frees a number of pages to the system
2042 * mem A pointer to the memory to be freed
2043 * size The size of the memory being freed
2044 * flags The original p->us_flags field
2050 page_free(void *mem, vm_size_t size, uint8_t flags)
2053 if ((flags & UMA_SLAB_BOOT) != 0) {
2054 startup_free(mem, size);
2058 KASSERT((flags & UMA_SLAB_KERNEL) != 0,
2059 ("UMA: page_free used with invalid flags %x", flags));
2061 kmem_free((vm_offset_t)mem, size);
2065 * Frees pcpu zone allocations
2068 * mem A pointer to the memory to be freed
2069 * size The size of the memory being freed
2070 * flags The original p->us_flags field
2076 pcpu_page_free(void *mem, vm_size_t size, uint8_t flags)
2078 vm_offset_t sva, curva;
2082 MPASS(size == (mp_maxid+1)*PAGE_SIZE);
2084 if ((flags & UMA_SLAB_BOOT) != 0) {
2085 startup_free(mem, size);
2089 sva = (vm_offset_t)mem;
2090 for (curva = sva; curva < sva + size; curva += PAGE_SIZE) {
2091 paddr = pmap_kextract(curva);
2092 m = PHYS_TO_VM_PAGE(paddr);
2093 vm_page_unwire_noq(m);
2096 pmap_qremove(sva, size >> PAGE_SHIFT);
2097 kva_free(sva, size);
2101 * Zero fill initializer
2103 * Arguments/Returns follow uma_init specifications
2106 zero_init(void *mem, int size, int flags)
2113 static struct noslabbits *
2114 slab_dbg_bits(uma_slab_t slab, uma_keg_t keg)
2117 return ((void *)((char *)&slab->us_free + BITSET_SIZE(keg->uk_ipers)));
2122 * Actual size of embedded struct slab (!OFFPAGE).
2125 slab_sizeof(int nitems)
2129 s = sizeof(struct uma_slab) + BITSET_SIZE(nitems) * SLAB_BITSETS;
2130 return (roundup(s, UMA_ALIGN_PTR + 1));
2133 #define UMA_FIXPT_SHIFT 31
2134 #define UMA_FRAC_FIXPT(n, d) \
2135 ((uint32_t)(((uint64_t)(n) << UMA_FIXPT_SHIFT) / (d)))
2136 #define UMA_FIXPT_PCT(f) \
2137 ((u_int)(((uint64_t)100 * (f)) >> UMA_FIXPT_SHIFT))
2138 #define UMA_PCT_FIXPT(pct) UMA_FRAC_FIXPT((pct), 100)
2139 #define UMA_MIN_EFF UMA_PCT_FIXPT(100 - UMA_MAX_WASTE)
2142 * Compute the number of items that will fit in a slab. If hdr is true, the
2143 * item count may be limited to provide space in the slab for an inline slab
2144 * header. Otherwise, all slab space will be provided for item storage.
2147 slab_ipers_hdr(u_int size, u_int rsize, u_int slabsize, bool hdr)
2152 /* The padding between items is not needed after the last item. */
2153 padpi = rsize - size;
2157 * Start with the maximum item count and remove items until
2158 * the slab header first alongside the allocatable memory.
2160 for (ipers = MIN(SLAB_MAX_SETSIZE,
2161 (slabsize + padpi - slab_sizeof(1)) / rsize);
2163 ipers * rsize - padpi + slab_sizeof(ipers) > slabsize;
2167 ipers = MIN((slabsize + padpi) / rsize, SLAB_MAX_SETSIZE);
2173 struct keg_layout_result {
2181 keg_layout_one(uma_keg_t keg, u_int rsize, u_int slabsize, u_int fmt,
2182 struct keg_layout_result *kl)
2187 kl->slabsize = slabsize;
2189 /* Handle INTERNAL as inline with an extra page. */
2190 if ((fmt & UMA_ZFLAG_INTERNAL) != 0) {
2191 kl->format &= ~UMA_ZFLAG_INTERNAL;
2192 kl->slabsize += PAGE_SIZE;
2195 kl->ipers = slab_ipers_hdr(keg->uk_size, rsize, kl->slabsize,
2196 (fmt & UMA_ZFLAG_OFFPAGE) == 0);
2198 /* Account for memory used by an offpage slab header. */
2199 total = kl->slabsize;
2200 if ((fmt & UMA_ZFLAG_OFFPAGE) != 0)
2201 total += slabzone(kl->ipers)->uz_keg->uk_rsize;
2203 kl->eff = UMA_FRAC_FIXPT(kl->ipers * rsize, total);
2207 * Determine the format of a uma keg. This determines where the slab header
2208 * will be placed (inline or offpage) and calculates ipers, rsize, and ppera.
2211 * keg The zone we should initialize
2217 keg_layout(uma_keg_t keg)
2219 struct keg_layout_result kl = {}, kl_tmp;
2228 KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0 ||
2229 (keg->uk_size <= UMA_PCPU_ALLOC_SIZE &&
2230 (keg->uk_flags & UMA_ZONE_CACHESPREAD) == 0),
2231 ("%s: cannot configure for PCPU: keg=%s, size=%u, flags=0x%b",
2232 __func__, keg->uk_name, keg->uk_size, keg->uk_flags,
2234 KASSERT((keg->uk_flags & (UMA_ZFLAG_INTERNAL | UMA_ZONE_VM)) == 0 ||
2235 (keg->uk_flags & (UMA_ZONE_NOTOUCH | UMA_ZONE_PCPU)) == 0,
2236 ("%s: incompatible flags 0x%b", __func__, keg->uk_flags,
2239 alignsize = keg->uk_align + 1;
2242 * ASAN requires that each allocation be aligned to the shadow map
2245 if (alignsize < KASAN_SHADOW_SCALE)
2246 alignsize = KASAN_SHADOW_SCALE;
2250 * Calculate the size of each allocation (rsize) according to
2251 * alignment. If the requested size is smaller than we have
2252 * allocation bits for we round it up.
2254 rsize = MAX(keg->uk_size, UMA_SMALLEST_UNIT);
2255 rsize = roundup2(rsize, alignsize);
2257 if ((keg->uk_flags & UMA_ZONE_CACHESPREAD) != 0) {
2259 * We want one item to start on every align boundary in a page.
2260 * To do this we will span pages. We will also extend the item
2261 * by the size of align if it is an even multiple of align.
2262 * Otherwise, it would fall on the same boundary every time.
2264 if ((rsize & alignsize) == 0)
2266 slabsize = rsize * (PAGE_SIZE / alignsize);
2267 slabsize = MIN(slabsize, rsize * SLAB_MAX_SETSIZE);
2268 slabsize = MIN(slabsize, UMA_CACHESPREAD_MAX_SIZE);
2269 slabsize = round_page(slabsize);
2272 * Start with a slab size of as many pages as it takes to
2273 * represent a single item. We will try to fit as many
2274 * additional items into the slab as possible.
2276 slabsize = round_page(keg->uk_size);
2279 /* Build a list of all of the available formats for this keg. */
2282 /* Evaluate an inline slab layout. */
2283 if ((keg->uk_flags & (UMA_ZONE_NOTOUCH | UMA_ZONE_PCPU)) == 0)
2286 /* TODO: vm_page-embedded slab. */
2289 * We can't do OFFPAGE if we're internal or if we've been
2290 * asked to not go to the VM for buckets. If we do this we
2291 * may end up going to the VM for slabs which we do not want
2292 * to do if we're UMA_ZONE_VM, which clearly forbids it.
2293 * In those cases, evaluate a pseudo-format called INTERNAL
2294 * which has an inline slab header and one extra page to
2295 * guarantee that it fits.
2297 * Otherwise, see if using an OFFPAGE slab will improve our
2300 if ((keg->uk_flags & (UMA_ZFLAG_INTERNAL | UMA_ZONE_VM)) != 0)
2301 fmts[nfmt++] = UMA_ZFLAG_INTERNAL;
2303 fmts[nfmt++] = UMA_ZFLAG_OFFPAGE;
2306 * Choose a slab size and format which satisfy the minimum efficiency.
2307 * Prefer the smallest slab size that meets the constraints.
2309 * Start with a minimum slab size, to accommodate CACHESPREAD. Then,
2310 * for small items (up to PAGE_SIZE), the iteration increment is one
2311 * page; and for large items, the increment is one item.
2313 i = (slabsize + rsize - keg->uk_size) / MAX(PAGE_SIZE, rsize);
2314 KASSERT(i >= 1, ("keg %s(%p) flags=0x%b slabsize=%u, rsize=%u, i=%u",
2315 keg->uk_name, keg, keg->uk_flags, PRINT_UMA_ZFLAGS, slabsize,
2318 slabsize = (rsize <= PAGE_SIZE) ? ptoa(i) :
2319 round_page(rsize * (i - 1) + keg->uk_size);
2321 for (j = 0; j < nfmt; j++) {
2322 /* Only if we have no viable format yet. */
2323 if ((fmts[j] & UMA_ZFLAG_INTERNAL) != 0 &&
2327 keg_layout_one(keg, rsize, slabsize, fmts[j], &kl_tmp);
2328 if (kl_tmp.eff <= kl.eff)
2333 CTR6(KTR_UMA, "keg %s layout: format %#x "
2334 "(ipers %u * rsize %u) / slabsize %#x = %u%% eff",
2335 keg->uk_name, kl.format, kl.ipers, rsize,
2336 kl.slabsize, UMA_FIXPT_PCT(kl.eff));
2338 /* Stop when we reach the minimum efficiency. */
2339 if (kl.eff >= UMA_MIN_EFF)
2343 if (kl.eff >= UMA_MIN_EFF || !multipage_slabs ||
2344 slabsize >= SLAB_MAX_SETSIZE * rsize ||
2345 (keg->uk_flags & (UMA_ZONE_PCPU | UMA_ZONE_CONTIG)) != 0)
2349 pages = atop(kl.slabsize);
2350 if ((keg->uk_flags & UMA_ZONE_PCPU) != 0)
2351 pages *= mp_maxid + 1;
2353 keg->uk_rsize = rsize;
2354 keg->uk_ipers = kl.ipers;
2355 keg->uk_ppera = pages;
2356 keg->uk_flags |= kl.format;
2359 * How do we find the slab header if it is offpage or if not all item
2360 * start addresses are in the same page? We could solve the latter
2361 * case with vaddr alignment, but we don't.
2363 if ((keg->uk_flags & UMA_ZFLAG_OFFPAGE) != 0 ||
2364 (keg->uk_ipers - 1) * rsize >= PAGE_SIZE) {
2365 if ((keg->uk_flags & UMA_ZONE_NOTPAGE) != 0)
2366 keg->uk_flags |= UMA_ZFLAG_HASH;
2368 keg->uk_flags |= UMA_ZFLAG_VTOSLAB;
2371 CTR6(KTR_UMA, "%s: keg=%s, flags=%#x, rsize=%u, ipers=%u, ppera=%u",
2372 __func__, keg->uk_name, keg->uk_flags, rsize, keg->uk_ipers,
2374 KASSERT(keg->uk_ipers > 0 && keg->uk_ipers <= SLAB_MAX_SETSIZE,
2375 ("%s: keg=%s, flags=0x%b, rsize=%u, ipers=%u, ppera=%u", __func__,
2376 keg->uk_name, keg->uk_flags, PRINT_UMA_ZFLAGS, rsize,
2377 keg->uk_ipers, pages));
2381 * Keg header ctor. This initializes all fields, locks, etc. And inserts
2382 * the keg onto the global keg list.
2384 * Arguments/Returns follow uma_ctor specifications
2385 * udata Actually uma_kctor_args
2388 keg_ctor(void *mem, int size, void *udata, int flags)
2390 struct uma_kctor_args *arg = udata;
2391 uma_keg_t keg = mem;
2396 keg->uk_size = arg->size;
2397 keg->uk_init = arg->uminit;
2398 keg->uk_fini = arg->fini;
2399 keg->uk_align = arg->align;
2400 keg->uk_reserve = 0;
2401 keg->uk_flags = arg->flags;
2404 * We use a global round-robin policy by default. Zones with
2405 * UMA_ZONE_FIRSTTOUCH set will use first-touch instead, in which
2406 * case the iterator is never run.
2408 keg->uk_dr.dr_policy = DOMAINSET_RR();
2409 keg->uk_dr.dr_iter = 0;
2412 * The primary zone is passed to us at keg-creation time.
2415 keg->uk_name = zone->uz_name;
2417 if (arg->flags & UMA_ZONE_ZINIT)
2418 keg->uk_init = zero_init;
2420 if (arg->flags & UMA_ZONE_MALLOC)
2421 keg->uk_flags |= UMA_ZFLAG_VTOSLAB;
2424 keg->uk_flags &= ~UMA_ZONE_PCPU;
2430 * Use a first-touch NUMA policy for kegs that pmap_extract() will
2431 * work on. Use round-robin for everything else.
2433 * Zones may override the default by specifying either.
2436 if ((keg->uk_flags &
2437 (UMA_ZONE_ROUNDROBIN | UMA_ZFLAG_CACHE | UMA_ZONE_NOTPAGE)) == 0)
2438 keg->uk_flags |= UMA_ZONE_FIRSTTOUCH;
2439 else if ((keg->uk_flags & UMA_ZONE_FIRSTTOUCH) == 0)
2440 keg->uk_flags |= UMA_ZONE_ROUNDROBIN;
2444 * If we haven't booted yet we need allocations to go through the
2445 * startup cache until the vm is ready.
2447 #ifdef UMA_MD_SMALL_ALLOC
2448 if (keg->uk_ppera == 1)
2449 keg->uk_allocf = uma_small_alloc;
2452 if (booted < BOOT_KVA)
2453 keg->uk_allocf = startup_alloc;
2454 else if (keg->uk_flags & UMA_ZONE_PCPU)
2455 keg->uk_allocf = pcpu_page_alloc;
2456 else if ((keg->uk_flags & UMA_ZONE_CONTIG) != 0 && keg->uk_ppera > 1)
2457 keg->uk_allocf = contig_alloc;
2459 keg->uk_allocf = page_alloc;
2460 #ifdef UMA_MD_SMALL_ALLOC
2461 if (keg->uk_ppera == 1)
2462 keg->uk_freef = uma_small_free;
2465 if (keg->uk_flags & UMA_ZONE_PCPU)
2466 keg->uk_freef = pcpu_page_free;
2468 keg->uk_freef = page_free;
2471 * Initialize keg's locks.
2473 for (i = 0; i < vm_ndomains; i++)
2474 KEG_LOCK_INIT(keg, i, (arg->flags & UMA_ZONE_MTXCLASS));
2477 * If we're putting the slab header in the actual page we need to
2478 * figure out where in each page it goes. See slab_sizeof
2481 if (!(keg->uk_flags & UMA_ZFLAG_OFFPAGE)) {
2484 shsize = slab_sizeof(keg->uk_ipers);
2485 keg->uk_pgoff = (PAGE_SIZE * keg->uk_ppera) - shsize;
2487 * The only way the following is possible is if with our
2488 * UMA_ALIGN_PTR adjustments we are now bigger than
2489 * UMA_SLAB_SIZE. I haven't checked whether this is
2490 * mathematically possible for all cases, so we make
2493 KASSERT(keg->uk_pgoff + shsize <= PAGE_SIZE * keg->uk_ppera,
2494 ("zone %s ipers %d rsize %d size %d slab won't fit",
2495 zone->uz_name, keg->uk_ipers, keg->uk_rsize, keg->uk_size));
2498 if (keg->uk_flags & UMA_ZFLAG_HASH)
2499 hash_alloc(&keg->uk_hash, 0);
2501 CTR3(KTR_UMA, "keg_ctor %p zone %s(%p)", keg, zone->uz_name, zone);
2503 LIST_INSERT_HEAD(&keg->uk_zones, zone, uz_link);
2505 rw_wlock(&uma_rwlock);
2506 LIST_INSERT_HEAD(&uma_kegs, keg, uk_link);
2507 rw_wunlock(&uma_rwlock);
2512 zone_kva_available(uma_zone_t zone, void *unused)
2516 if ((zone->uz_flags & UMA_ZFLAG_CACHE) != 0)
2520 if (keg->uk_allocf == startup_alloc) {
2521 /* Switch to the real allocator. */
2522 if (keg->uk_flags & UMA_ZONE_PCPU)
2523 keg->uk_allocf = pcpu_page_alloc;
2524 else if ((keg->uk_flags & UMA_ZONE_CONTIG) != 0 &&
2526 keg->uk_allocf = contig_alloc;
2528 keg->uk_allocf = page_alloc;
2533 zone_alloc_counters(uma_zone_t zone, void *unused)
2536 zone->uz_allocs = counter_u64_alloc(M_WAITOK);
2537 zone->uz_frees = counter_u64_alloc(M_WAITOK);
2538 zone->uz_fails = counter_u64_alloc(M_WAITOK);
2539 zone->uz_xdomain = counter_u64_alloc(M_WAITOK);
2543 zone_alloc_sysctl(uma_zone_t zone, void *unused)
2545 uma_zone_domain_t zdom;
2548 struct sysctl_oid *oid, *domainoid;
2549 int domains, i, cnt;
2550 static const char *nokeg = "cache zone";
2554 * Make a sysctl safe copy of the zone name by removing
2555 * any special characters and handling dups by appending
2558 if (zone->uz_namecnt != 0) {
2559 /* Count the number of decimal digits and '_' separator. */
2560 for (i = 1, cnt = zone->uz_namecnt; cnt != 0; i++)
2562 zone->uz_ctlname = malloc(strlen(zone->uz_name) + i + 1,
2564 sprintf(zone->uz_ctlname, "%s_%d", zone->uz_name,
2567 zone->uz_ctlname = strdup(zone->uz_name, M_UMA);
2568 for (c = zone->uz_ctlname; *c != '\0'; c++)
2569 if (strchr("./\\ -", *c) != NULL)
2573 * Basic parameters at the root.
2575 zone->uz_oid = SYSCTL_ADD_NODE(NULL, SYSCTL_STATIC_CHILDREN(_vm_uma),
2576 OID_AUTO, zone->uz_ctlname, CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2578 SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2579 "size", CTLFLAG_RD, &zone->uz_size, 0, "Allocation size");
2580 SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2581 "flags", CTLFLAG_RD | CTLTYPE_STRING | CTLFLAG_MPSAFE,
2582 zone, 0, sysctl_handle_uma_zone_flags, "A",
2583 "Allocator configuration flags");
2584 SYSCTL_ADD_U16(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2585 "bucket_size", CTLFLAG_RD, &zone->uz_bucket_size, 0,
2586 "Desired per-cpu cache size");
2587 SYSCTL_ADD_U16(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2588 "bucket_size_max", CTLFLAG_RD, &zone->uz_bucket_size_max, 0,
2589 "Maximum allowed per-cpu cache size");
2594 if ((zone->uz_flags & UMA_ZFLAG_HASH) == 0)
2595 domains = vm_ndomains;
2598 oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(zone->uz_oid), OID_AUTO,
2599 "keg", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2601 if ((zone->uz_flags & UMA_ZFLAG_CACHE) == 0) {
2602 SYSCTL_ADD_CONST_STRING(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2603 "name", CTLFLAG_RD, keg->uk_name, "Keg name");
2604 SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2605 "rsize", CTLFLAG_RD, &keg->uk_rsize, 0,
2606 "Real object size with alignment");
2607 SYSCTL_ADD_U16(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2608 "ppera", CTLFLAG_RD, &keg->uk_ppera, 0,
2609 "pages per-slab allocation");
2610 SYSCTL_ADD_U16(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2611 "ipers", CTLFLAG_RD, &keg->uk_ipers, 0,
2612 "items available per-slab");
2613 SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2614 "align", CTLFLAG_RD, &keg->uk_align, 0,
2615 "item alignment mask");
2616 SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2617 "reserve", CTLFLAG_RD, &keg->uk_reserve, 0,
2618 "number of reserved items");
2619 SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2620 "efficiency", CTLFLAG_RD | CTLTYPE_INT | CTLFLAG_MPSAFE,
2621 keg, 0, sysctl_handle_uma_slab_efficiency, "I",
2622 "Slab utilization (100 - internal fragmentation %)");
2623 domainoid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(oid),
2624 OID_AUTO, "domain", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2625 for (i = 0; i < domains; i++) {
2626 dom = &keg->uk_domain[i];
2627 oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(domainoid),
2628 OID_AUTO, VM_DOMAIN(i)->vmd_name,
2629 CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2630 SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2631 "pages", CTLFLAG_RD, &dom->ud_pages, 0,
2632 "Total pages currently allocated from VM");
2633 SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2634 "free_items", CTLFLAG_RD, &dom->ud_free_items, 0,
2635 "Items free in the slab layer");
2636 SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2637 "free_slabs", CTLFLAG_RD, &dom->ud_free_slabs, 0,
2641 SYSCTL_ADD_CONST_STRING(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2642 "name", CTLFLAG_RD, nokeg, "Keg name");
2645 * Information about zone limits.
2647 oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(zone->uz_oid), OID_AUTO,
2648 "limit", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2649 SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2650 "items", CTLFLAG_RD | CTLTYPE_U64 | CTLFLAG_MPSAFE,
2651 zone, 0, sysctl_handle_uma_zone_items, "QU",
2652 "Current number of allocated items if limit is set");
2653 SYSCTL_ADD_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2654 "max_items", CTLFLAG_RD, &zone->uz_max_items, 0,
2655 "Maximum number of allocated and cached items");
2656 SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2657 "sleepers", CTLFLAG_RD, &zone->uz_sleepers, 0,
2658 "Number of threads sleeping at limit");
2659 SYSCTL_ADD_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2660 "sleeps", CTLFLAG_RD, &zone->uz_sleeps, 0,
2661 "Total zone limit sleeps");
2662 SYSCTL_ADD_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2663 "bucket_max", CTLFLAG_RD, &zone->uz_bucket_max, 0,
2664 "Maximum number of items in each domain's bucket cache");
2667 * Per-domain zone information.
2669 domainoid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(zone->uz_oid),
2670 OID_AUTO, "domain", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2671 for (i = 0; i < domains; i++) {
2672 zdom = ZDOM_GET(zone, i);
2673 oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(domainoid),
2674 OID_AUTO, VM_DOMAIN(i)->vmd_name,
2675 CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2676 SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2677 "nitems", CTLFLAG_RD, &zdom->uzd_nitems,
2678 "number of items in this domain");
2679 SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2680 "imax", CTLFLAG_RD, &zdom->uzd_imax,
2681 "maximum item count in this period");
2682 SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2683 "imin", CTLFLAG_RD, &zdom->uzd_imin,
2684 "minimum item count in this period");
2685 SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2686 "bimin", CTLFLAG_RD, &zdom->uzd_bimin,
2687 "Minimum item count in this batch");
2688 SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2689 "wss", CTLFLAG_RD, &zdom->uzd_wss,
2690 "Working set size");
2691 SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2692 "limin", CTLFLAG_RD, &zdom->uzd_limin,
2693 "Long time minimum item count");
2694 SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2695 "timin", CTLFLAG_RD, &zdom->uzd_timin, 0,
2696 "Time since zero long time minimum item count");
2700 * General statistics.
2702 oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(zone->uz_oid), OID_AUTO,
2703 "stats", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2704 SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2705 "current", CTLFLAG_RD | CTLTYPE_INT | CTLFLAG_MPSAFE,
2706 zone, 1, sysctl_handle_uma_zone_cur, "I",
2707 "Current number of allocated items");
2708 SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2709 "allocs", CTLFLAG_RD | CTLTYPE_U64 | CTLFLAG_MPSAFE,
2710 zone, 0, sysctl_handle_uma_zone_allocs, "QU",
2711 "Total allocation calls");
2712 SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2713 "frees", CTLFLAG_RD | CTLTYPE_U64 | CTLFLAG_MPSAFE,
2714 zone, 0, sysctl_handle_uma_zone_frees, "QU",
2715 "Total free calls");
2716 SYSCTL_ADD_COUNTER_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2717 "fails", CTLFLAG_RD, &zone->uz_fails,
2718 "Number of allocation failures");
2719 SYSCTL_ADD_COUNTER_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2720 "xdomain", CTLFLAG_RD, &zone->uz_xdomain,
2721 "Free calls from the wrong domain");
2724 struct uma_zone_count {
2730 zone_count(uma_zone_t zone, void *arg)
2732 struct uma_zone_count *cnt;
2736 * Some zones are rapidly created with identical names and
2737 * destroyed out of order. This can lead to gaps in the count.
2738 * Use one greater than the maximum observed for this name.
2740 if (strcmp(zone->uz_name, cnt->name) == 0)
2741 cnt->count = MAX(cnt->count,
2742 zone->uz_namecnt + 1);
2746 zone_update_caches(uma_zone_t zone)
2750 for (i = 0; i <= mp_maxid; i++) {
2751 cache_set_uz_size(&zone->uz_cpu[i], zone->uz_size);
2752 cache_set_uz_flags(&zone->uz_cpu[i], zone->uz_flags);
2757 * Zone header ctor. This initializes all fields, locks, etc.
2759 * Arguments/Returns follow uma_ctor specifications
2760 * udata Actually uma_zctor_args
2763 zone_ctor(void *mem, int size, void *udata, int flags)
2765 struct uma_zone_count cnt;
2766 struct uma_zctor_args *arg = udata;
2767 uma_zone_domain_t zdom;
2768 uma_zone_t zone = mem;
2774 zone->uz_name = arg->name;
2775 zone->uz_ctor = arg->ctor;
2776 zone->uz_dtor = arg->dtor;
2777 zone->uz_init = NULL;
2778 zone->uz_fini = NULL;
2779 zone->uz_sleeps = 0;
2780 zone->uz_bucket_size = 0;
2781 zone->uz_bucket_size_min = 0;
2782 zone->uz_bucket_size_max = BUCKET_MAX;
2783 zone->uz_flags = (arg->flags & UMA_ZONE_SMR);
2784 zone->uz_warning = NULL;
2785 /* The domain structures follow the cpu structures. */
2786 zone->uz_bucket_max = ULONG_MAX;
2787 timevalclear(&zone->uz_ratecheck);
2789 /* Count the number of duplicate names. */
2790 cnt.name = arg->name;
2792 zone_foreach(zone_count, &cnt);
2793 zone->uz_namecnt = cnt.count;
2794 ZONE_CROSS_LOCK_INIT(zone);
2796 for (i = 0; i < vm_ndomains; i++) {
2797 zdom = ZDOM_GET(zone, i);
2798 ZDOM_LOCK_INIT(zone, zdom, (arg->flags & UMA_ZONE_MTXCLASS));
2799 STAILQ_INIT(&zdom->uzd_buckets);
2802 #if defined(INVARIANTS) && !defined(KASAN)
2803 if (arg->uminit == trash_init && arg->fini == trash_fini)
2804 zone->uz_flags |= UMA_ZFLAG_TRASH | UMA_ZFLAG_CTORDTOR;
2805 #elif defined(KASAN)
2806 if ((arg->flags & (UMA_ZONE_NOFREE | UMA_ZFLAG_CACHE)) != 0)
2807 arg->flags |= UMA_ZONE_NOKASAN;
2811 * This is a pure cache zone, no kegs.
2814 KASSERT((arg->flags & UMA_ZFLAG_CACHE) != 0,
2815 ("zone_ctor: Import specified for non-cache zone."));
2816 zone->uz_flags = arg->flags;
2817 zone->uz_size = arg->size;
2818 zone->uz_import = arg->import;
2819 zone->uz_release = arg->release;
2820 zone->uz_arg = arg->arg;
2823 * Cache zones are round-robin unless a policy is
2824 * specified because they may have incompatible
2827 if ((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) == 0)
2828 zone->uz_flags |= UMA_ZONE_ROUNDROBIN;
2830 rw_wlock(&uma_rwlock);
2831 LIST_INSERT_HEAD(&uma_cachezones, zone, uz_link);
2832 rw_wunlock(&uma_rwlock);
2837 * Use the regular zone/keg/slab allocator.
2839 zone->uz_import = zone_import;
2840 zone->uz_release = zone_release;
2841 zone->uz_arg = zone;
2844 if (arg->flags & UMA_ZONE_SECONDARY) {
2845 KASSERT((zone->uz_flags & UMA_ZONE_SECONDARY) == 0,
2846 ("Secondary zone requested UMA_ZFLAG_INTERNAL"));
2847 KASSERT(arg->keg != NULL, ("Secondary zone on zero'd keg"));
2848 zone->uz_init = arg->uminit;
2849 zone->uz_fini = arg->fini;
2850 zone->uz_flags |= UMA_ZONE_SECONDARY;
2851 rw_wlock(&uma_rwlock);
2853 LIST_FOREACH(z, &keg->uk_zones, uz_link) {
2854 if (LIST_NEXT(z, uz_link) == NULL) {
2855 LIST_INSERT_AFTER(z, zone, uz_link);
2860 rw_wunlock(&uma_rwlock);
2861 } else if (keg == NULL) {
2862 if ((keg = uma_kcreate(zone, arg->size, arg->uminit, arg->fini,
2863 arg->align, arg->flags)) == NULL)
2866 struct uma_kctor_args karg;
2869 /* We should only be here from uma_startup() */
2870 karg.size = arg->size;
2871 karg.uminit = arg->uminit;
2872 karg.fini = arg->fini;
2873 karg.align = arg->align;
2874 karg.flags = (arg->flags & ~UMA_ZONE_SMR);
2876 error = keg_ctor(arg->keg, sizeof(struct uma_keg), &karg,
2882 /* Inherit properties from the keg. */
2884 zone->uz_size = keg->uk_size;
2885 zone->uz_flags |= (keg->uk_flags &
2886 (UMA_ZONE_INHERIT | UMA_ZFLAG_INHERIT));
2889 if (booted >= BOOT_PCPU) {
2890 zone_alloc_counters(zone, NULL);
2891 if (booted >= BOOT_RUNNING)
2892 zone_alloc_sysctl(zone, NULL);
2894 zone->uz_allocs = EARLY_COUNTER;
2895 zone->uz_frees = EARLY_COUNTER;
2896 zone->uz_fails = EARLY_COUNTER;
2899 /* Caller requests a private SMR context. */
2900 if ((zone->uz_flags & UMA_ZONE_SMR) != 0)
2901 zone->uz_smr = smr_create(zone->uz_name, 0, 0);
2903 KASSERT((arg->flags & (UMA_ZONE_MAXBUCKET | UMA_ZONE_NOBUCKET)) !=
2904 (UMA_ZONE_MAXBUCKET | UMA_ZONE_NOBUCKET),
2905 ("Invalid zone flag combination"));
2906 if (arg->flags & UMA_ZFLAG_INTERNAL)
2907 zone->uz_bucket_size_max = zone->uz_bucket_size = 0;
2908 if ((arg->flags & UMA_ZONE_MAXBUCKET) != 0)
2909 zone->uz_bucket_size = BUCKET_MAX;
2910 else if ((arg->flags & UMA_ZONE_NOBUCKET) != 0)
2911 zone->uz_bucket_size = 0;
2913 zone->uz_bucket_size = bucket_select(zone->uz_size);
2914 zone->uz_bucket_size_min = zone->uz_bucket_size;
2915 if (zone->uz_dtor != NULL || zone->uz_ctor != NULL)
2916 zone->uz_flags |= UMA_ZFLAG_CTORDTOR;
2917 zone_update_caches(zone);
2923 * Keg header dtor. This frees all data, destroys locks, frees the hash
2924 * table and removes the keg from the global list.
2926 * Arguments/Returns follow uma_dtor specifications
2930 keg_dtor(void *arg, int size, void *udata)
2933 uint32_t free, pages;
2936 keg = (uma_keg_t)arg;
2938 for (i = 0; i < vm_ndomains; i++) {
2939 free += keg->uk_domain[i].ud_free_items;
2940 pages += keg->uk_domain[i].ud_pages;
2941 KEG_LOCK_FINI(keg, i);
2944 printf("Freed UMA keg (%s) was not empty (%u items). "
2945 " Lost %u pages of memory.\n",
2946 keg->uk_name ? keg->uk_name : "",
2947 pages / keg->uk_ppera * keg->uk_ipers - free, pages);
2949 hash_free(&keg->uk_hash);
2955 * Arguments/Returns follow uma_dtor specifications
2959 zone_dtor(void *arg, int size, void *udata)
2965 zone = (uma_zone_t)arg;
2967 sysctl_remove_oid(zone->uz_oid, 1, 1);
2969 if (!(zone->uz_flags & UMA_ZFLAG_INTERNAL))
2972 rw_wlock(&uma_rwlock);
2973 LIST_REMOVE(zone, uz_link);
2974 rw_wunlock(&uma_rwlock);
2975 if ((zone->uz_flags & (UMA_ZONE_SECONDARY | UMA_ZFLAG_CACHE)) == 0) {
2977 keg->uk_reserve = 0;
2979 zone_reclaim(zone, UMA_ANYDOMAIN, M_WAITOK, true);
2982 * We only destroy kegs from non secondary/non cache zones.
2984 if ((zone->uz_flags & (UMA_ZONE_SECONDARY | UMA_ZFLAG_CACHE)) == 0) {
2986 rw_wlock(&uma_rwlock);
2987 LIST_REMOVE(keg, uk_link);
2988 rw_wunlock(&uma_rwlock);
2989 zone_free_item(kegs, keg, NULL, SKIP_NONE);
2991 counter_u64_free(zone->uz_allocs);
2992 counter_u64_free(zone->uz_frees);
2993 counter_u64_free(zone->uz_fails);
2994 counter_u64_free(zone->uz_xdomain);
2995 free(zone->uz_ctlname, M_UMA);
2996 for (i = 0; i < vm_ndomains; i++)
2997 ZDOM_LOCK_FINI(ZDOM_GET(zone, i));
2998 ZONE_CROSS_LOCK_FINI(zone);
3002 zone_foreach_unlocked(void (*zfunc)(uma_zone_t, void *arg), void *arg)
3007 LIST_FOREACH(keg, &uma_kegs, uk_link) {
3008 LIST_FOREACH(zone, &keg->uk_zones, uz_link)
3011 LIST_FOREACH(zone, &uma_cachezones, uz_link)
3016 * Traverses every zone in the system and calls a callback
3019 * zfunc A pointer to a function which accepts a zone
3026 zone_foreach(void (*zfunc)(uma_zone_t, void *arg), void *arg)
3029 rw_rlock(&uma_rwlock);
3030 zone_foreach_unlocked(zfunc, arg);
3031 rw_runlock(&uma_rwlock);
3035 * Initialize the kernel memory allocator. This is done after pages can be
3036 * allocated but before general KVA is available.
3039 uma_startup1(vm_offset_t virtual_avail)
3041 struct uma_zctor_args args;
3042 size_t ksize, zsize, size;
3043 uma_keg_t primarykeg;
3048 bootstart = bootmem = virtual_avail;
3050 rw_init(&uma_rwlock, "UMA lock");
3051 sx_init(&uma_reclaim_lock, "umareclaim");
3053 ksize = sizeof(struct uma_keg) +
3054 (sizeof(struct uma_domain) * vm_ndomains);
3055 ksize = roundup(ksize, UMA_SUPER_ALIGN);
3056 zsize = sizeof(struct uma_zone) +
3057 (sizeof(struct uma_cache) * (mp_maxid + 1)) +
3058 (sizeof(struct uma_zone_domain) * vm_ndomains);
3059 zsize = roundup(zsize, UMA_SUPER_ALIGN);
3061 /* Allocate the zone of zones, zone of kegs, and zone of zones keg. */
3062 size = (zsize * 2) + ksize;
3063 for (domain = 0; domain < vm_ndomains; domain++) {
3064 m = (uintptr_t)startup_alloc(NULL, size, domain, &pflag,
3069 zones = (uma_zone_t)m;
3071 kegs = (uma_zone_t)m;
3073 primarykeg = (uma_keg_t)m;
3075 /* "manually" create the initial zone */
3076 memset(&args, 0, sizeof(args));
3077 args.name = "UMA Kegs";
3079 args.ctor = keg_ctor;
3080 args.dtor = keg_dtor;
3081 args.uminit = zero_init;
3083 args.keg = primarykeg;
3084 args.align = UMA_SUPER_ALIGN - 1;
3085 args.flags = UMA_ZFLAG_INTERNAL;
3086 zone_ctor(kegs, zsize, &args, M_WAITOK);
3088 args.name = "UMA Zones";
3090 args.ctor = zone_ctor;
3091 args.dtor = zone_dtor;
3092 args.uminit = zero_init;
3095 args.align = UMA_SUPER_ALIGN - 1;
3096 args.flags = UMA_ZFLAG_INTERNAL;
3097 zone_ctor(zones, zsize, &args, M_WAITOK);
3099 /* Now make zones for slab headers */
3100 slabzones[0] = uma_zcreate("UMA Slabs 0", SLABZONE0_SIZE,
3101 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
3102 slabzones[1] = uma_zcreate("UMA Slabs 1", SLABZONE1_SIZE,
3103 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
3105 hashzone = uma_zcreate("UMA Hash",
3106 sizeof(struct slabhead *) * UMA_HASH_SIZE_INIT,
3107 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
3113 #ifndef UMA_MD_SMALL_ALLOC
3114 extern void vm_radix_reserve_kva(void);
3118 * Advertise the availability of normal kva allocations and switch to
3119 * the default back-end allocator. Marks the KVA we consumed on startup
3120 * as used in the map.
3126 if (bootstart != bootmem) {
3127 vm_map_lock(kernel_map);
3128 (void)vm_map_insert(kernel_map, NULL, 0, bootstart, bootmem,
3129 VM_PROT_RW, VM_PROT_RW, MAP_NOFAULT);
3130 vm_map_unlock(kernel_map);
3133 #ifndef UMA_MD_SMALL_ALLOC
3134 /* Set up radix zone to use noobj_alloc. */
3135 vm_radix_reserve_kva();
3139 zone_foreach_unlocked(zone_kva_available, NULL);
3144 * Allocate counters as early as possible so that boot-time allocations are
3145 * accounted more precisely.
3148 uma_startup_pcpu(void *arg __unused)
3151 zone_foreach_unlocked(zone_alloc_counters, NULL);
3154 SYSINIT(uma_startup_pcpu, SI_SUB_COUNTER, SI_ORDER_ANY, uma_startup_pcpu, NULL);
3157 * Finish our initialization steps.
3160 uma_startup3(void *arg __unused)
3164 TUNABLE_INT_FETCH("vm.debug.divisor", &dbg_divisor);
3165 uma_dbg_cnt = counter_u64_alloc(M_WAITOK);
3166 uma_skip_cnt = counter_u64_alloc(M_WAITOK);
3168 zone_foreach_unlocked(zone_alloc_sysctl, NULL);
3169 callout_init(&uma_callout, 1);
3170 callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL);
3171 booted = BOOT_RUNNING;
3173 EVENTHANDLER_REGISTER(shutdown_post_sync, uma_shutdown, NULL,
3174 EVENTHANDLER_PRI_FIRST);
3176 SYSINIT(uma_startup3, SI_SUB_VM_CONF, SI_ORDER_SECOND, uma_startup3, NULL);
3182 booted = BOOT_SHUTDOWN;
3186 uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit, uma_fini fini,
3187 int align, uint32_t flags)
3189 struct uma_kctor_args args;
3192 args.uminit = uminit;
3194 args.align = (align == UMA_ALIGN_CACHE) ? uma_align_cache : align;
3197 return (zone_alloc_item(kegs, &args, UMA_ANYDOMAIN, M_WAITOK));
3200 /* Public functions */
3203 uma_set_align(int align)
3206 if (align != UMA_ALIGN_CACHE)
3207 uma_align_cache = align;
3212 uma_zcreate(const char *name, size_t size, uma_ctor ctor, uma_dtor dtor,
3213 uma_init uminit, uma_fini fini, int align, uint32_t flags)
3216 struct uma_zctor_args args;
3219 KASSERT(powerof2(align + 1), ("invalid zone alignment %d for \"%s\"",
3222 /* This stuff is essential for the zone ctor */
3223 memset(&args, 0, sizeof(args));
3228 args.uminit = uminit;
3230 #if defined(INVARIANTS) && !defined(KASAN)
3232 * Inject procedures which check for memory use after free if we are
3233 * allowed to scramble the memory while it is not allocated. This
3234 * requires that: UMA is actually able to access the memory, no init
3235 * or fini procedures, no dependency on the initial value of the
3236 * memory, and no (legitimate) use of the memory after free. Note,
3237 * the ctor and dtor do not need to be empty.
3239 if ((!(flags & (UMA_ZONE_ZINIT | UMA_ZONE_NOTOUCH |
3240 UMA_ZONE_NOFREE))) && uminit == NULL && fini == NULL) {
3241 args.uminit = trash_init;
3242 args.fini = trash_fini;
3249 sx_xlock(&uma_reclaim_lock);
3250 res = zone_alloc_item(zones, &args, UMA_ANYDOMAIN, M_WAITOK);
3251 sx_xunlock(&uma_reclaim_lock);
3258 uma_zsecond_create(const char *name, uma_ctor ctor, uma_dtor dtor,
3259 uma_init zinit, uma_fini zfini, uma_zone_t primary)
3261 struct uma_zctor_args args;
3265 keg = primary->uz_keg;
3266 memset(&args, 0, sizeof(args));
3268 args.size = keg->uk_size;
3271 args.uminit = zinit;
3273 args.align = keg->uk_align;
3274 args.flags = keg->uk_flags | UMA_ZONE_SECONDARY;
3277 sx_xlock(&uma_reclaim_lock);
3278 res = zone_alloc_item(zones, &args, UMA_ANYDOMAIN, M_WAITOK);
3279 sx_xunlock(&uma_reclaim_lock);
3286 uma_zcache_create(const char *name, int size, uma_ctor ctor, uma_dtor dtor,
3287 uma_init zinit, uma_fini zfini, uma_import zimport, uma_release zrelease,
3288 void *arg, int flags)
3290 struct uma_zctor_args args;
3292 memset(&args, 0, sizeof(args));
3297 args.uminit = zinit;
3299 args.import = zimport;
3300 args.release = zrelease;
3303 args.flags = flags | UMA_ZFLAG_CACHE;
3305 return (zone_alloc_item(zones, &args, UMA_ANYDOMAIN, M_WAITOK));
3310 uma_zdestroy(uma_zone_t zone)
3314 * Large slabs are expensive to reclaim, so don't bother doing
3315 * unnecessary work if we're shutting down.
3317 if (booted == BOOT_SHUTDOWN &&
3318 zone->uz_fini == NULL && zone->uz_release == zone_release)
3320 sx_xlock(&uma_reclaim_lock);
3321 zone_free_item(zones, zone, NULL, SKIP_NONE);
3322 sx_xunlock(&uma_reclaim_lock);
3326 uma_zwait(uma_zone_t zone)
3329 if ((zone->uz_flags & UMA_ZONE_SMR) != 0)
3330 uma_zfree_smr(zone, uma_zalloc_smr(zone, M_WAITOK));
3331 else if ((zone->uz_flags & UMA_ZONE_PCPU) != 0)
3332 uma_zfree_pcpu(zone, uma_zalloc_pcpu(zone, M_WAITOK));
3334 uma_zfree(zone, uma_zalloc(zone, M_WAITOK));
3338 uma_zalloc_pcpu_arg(uma_zone_t zone, void *udata, int flags)
3340 void *item, *pcpu_item;
3344 MPASS(zone->uz_flags & UMA_ZONE_PCPU);
3346 item = uma_zalloc_arg(zone, udata, flags & ~M_ZERO);
3349 pcpu_item = zpcpu_base_to_offset(item);
3350 if (flags & M_ZERO) {
3352 for (i = 0; i <= mp_maxid; i++)
3353 bzero(zpcpu_get_cpu(pcpu_item, i), zone->uz_size);
3355 bzero(item, zone->uz_size);
3362 * A stub while both regular and pcpu cases are identical.
3365 uma_zfree_pcpu_arg(uma_zone_t zone, void *pcpu_item, void *udata)
3370 MPASS(zone->uz_flags & UMA_ZONE_PCPU);
3373 /* uma_zfree_pcu_*(..., NULL) does nothing, to match free(9). */
3374 if (pcpu_item == NULL)
3377 item = zpcpu_offset_to_base(pcpu_item);
3378 uma_zfree_arg(zone, item, udata);
3381 static inline void *
3382 item_ctor(uma_zone_t zone, int uz_flags, int size, void *udata, int flags,
3389 kasan_mark_item_valid(zone, item);
3392 skipdbg = uma_dbg_zskip(zone, item);
3393 if (!skipdbg && (uz_flags & UMA_ZFLAG_TRASH) != 0 &&
3394 zone->uz_ctor != trash_ctor)
3395 trash_ctor(item, size, udata, flags);
3398 /* Check flags before loading ctor pointer. */
3399 if (__predict_false((uz_flags & UMA_ZFLAG_CTORDTOR) != 0) &&
3400 __predict_false(zone->uz_ctor != NULL) &&
3401 zone->uz_ctor(item, size, udata, flags) != 0) {
3402 counter_u64_add(zone->uz_fails, 1);
3403 zone_free_item(zone, item, udata, SKIP_DTOR | SKIP_CNT);
3408 uma_dbg_alloc(zone, NULL, item);
3410 if (__predict_false(flags & M_ZERO))
3411 return (memset(item, 0, size));
3417 item_dtor(uma_zone_t zone, void *item, int size, void *udata,
3418 enum zfreeskip skip)
3423 skipdbg = uma_dbg_zskip(zone, item);
3424 if (skip == SKIP_NONE && !skipdbg) {
3425 if ((zone->uz_flags & UMA_ZONE_MALLOC) != 0)
3426 uma_dbg_free(zone, udata, item);
3428 uma_dbg_free(zone, NULL, item);
3431 if (__predict_true(skip < SKIP_DTOR)) {
3432 if (zone->uz_dtor != NULL)
3433 zone->uz_dtor(item, size, udata);
3435 if (!skipdbg && (zone->uz_flags & UMA_ZFLAG_TRASH) != 0 &&
3436 zone->uz_dtor != trash_dtor)
3437 trash_dtor(item, size, udata);
3440 kasan_mark_item_invalid(zone, item);
3445 item_domain(void *item)
3449 domain = vm_phys_domain(vtophys(item));
3450 KASSERT(domain >= 0 && domain < vm_ndomains,
3451 ("%s: unknown domain for item %p", __func__, item));
3456 #if defined(INVARIANTS) || defined(DEBUG_MEMGUARD) || defined(WITNESS)
3457 #define UMA_ZALLOC_DEBUG
3459 uma_zalloc_debug(uma_zone_t zone, void **itemp, void *udata, int flags)
3465 if (flags & M_WAITOK) {
3466 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
3467 "uma_zalloc_debug: zone \"%s\"", zone->uz_name);
3472 KASSERT((flags & M_EXEC) == 0,
3473 ("uma_zalloc_debug: called with M_EXEC"));
3474 KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
3475 ("uma_zalloc_debug: called within spinlock or critical section"));
3476 KASSERT((zone->uz_flags & UMA_ZONE_PCPU) == 0 || (flags & M_ZERO) == 0,
3477 ("uma_zalloc_debug: allocating from a pcpu zone with M_ZERO"));
3480 #ifdef DEBUG_MEMGUARD
3481 if ((zone->uz_flags & UMA_ZONE_SMR) == 0 && memguard_cmp_zone(zone)) {
3483 item = memguard_alloc(zone->uz_size, flags);
3485 error = EJUSTRETURN;
3486 if (zone->uz_init != NULL &&
3487 zone->uz_init(item, zone->uz_size, flags) != 0) {
3491 if (zone->uz_ctor != NULL &&
3492 zone->uz_ctor(item, zone->uz_size, udata,
3494 counter_u64_add(zone->uz_fails, 1);
3495 zone->uz_fini(item, zone->uz_size);
3502 /* This is unfortunate but should not be fatal. */
3509 uma_zfree_debug(uma_zone_t zone, void *item, void *udata)
3511 KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
3512 ("uma_zfree_debug: called with spinlock or critical section held"));
3514 #ifdef DEBUG_MEMGUARD
3515 if ((zone->uz_flags & UMA_ZONE_SMR) == 0 && is_memguard_addr(item)) {
3516 if (zone->uz_dtor != NULL)
3517 zone->uz_dtor(item, zone->uz_size, udata);
3518 if (zone->uz_fini != NULL)
3519 zone->uz_fini(item, zone->uz_size);
3520 memguard_free(item);
3521 return (EJUSTRETURN);
3528 static inline void *
3529 cache_alloc_item(uma_zone_t zone, uma_cache_t cache, uma_cache_bucket_t bucket,
3530 void *udata, int flags)
3535 item = cache_bucket_pop(cache, bucket);
3536 size = cache_uz_size(cache);
3537 uz_flags = cache_uz_flags(cache);
3539 return (item_ctor(zone, uz_flags, size, udata, flags, item));
3542 static __noinline void *
3543 cache_alloc_retry(uma_zone_t zone, uma_cache_t cache, void *udata, int flags)
3545 uma_cache_bucket_t bucket;
3548 while (cache_alloc(zone, cache, udata, flags)) {
3549 cache = &zone->uz_cpu[curcpu];
3550 bucket = &cache->uc_allocbucket;
3551 if (__predict_false(bucket->ucb_cnt == 0))
3553 return (cache_alloc_item(zone, cache, bucket, udata, flags));
3558 * We can not get a bucket so try to return a single item.
3560 if (zone->uz_flags & UMA_ZONE_FIRSTTOUCH)
3561 domain = PCPU_GET(domain);
3563 domain = UMA_ANYDOMAIN;
3564 return (zone_alloc_item(zone, udata, domain, flags));
3569 uma_zalloc_smr(uma_zone_t zone, int flags)
3571 uma_cache_bucket_t bucket;
3574 #ifdef UMA_ZALLOC_DEBUG
3577 KASSERT((zone->uz_flags & UMA_ZONE_SMR) != 0,
3578 ("uma_zalloc_arg: called with non-SMR zone."));
3579 if (uma_zalloc_debug(zone, &item, NULL, flags) == EJUSTRETURN)
3584 cache = &zone->uz_cpu[curcpu];
3585 bucket = &cache->uc_allocbucket;
3586 if (__predict_false(bucket->ucb_cnt == 0))
3587 return (cache_alloc_retry(zone, cache, NULL, flags));
3588 return (cache_alloc_item(zone, cache, bucket, NULL, flags));
3593 uma_zalloc_arg(uma_zone_t zone, void *udata, int flags)
3595 uma_cache_bucket_t bucket;
3598 /* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
3599 random_harvest_fast_uma(&zone, sizeof(zone), RANDOM_UMA);
3601 /* This is the fast path allocation */
3602 CTR3(KTR_UMA, "uma_zalloc_arg zone %s(%p) flags %d", zone->uz_name,
3605 #ifdef UMA_ZALLOC_DEBUG
3608 KASSERT((zone->uz_flags & UMA_ZONE_SMR) == 0,
3609 ("uma_zalloc_arg: called with SMR zone."));
3610 if (uma_zalloc_debug(zone, &item, udata, flags) == EJUSTRETURN)
3615 * If possible, allocate from the per-CPU cache. There are two
3616 * requirements for safe access to the per-CPU cache: (1) the thread
3617 * accessing the cache must not be preempted or yield during access,
3618 * and (2) the thread must not migrate CPUs without switching which
3619 * cache it accesses. We rely on a critical section to prevent
3620 * preemption and migration. We release the critical section in
3621 * order to acquire the zone mutex if we are unable to allocate from
3622 * the current cache; when we re-acquire the critical section, we
3623 * must detect and handle migration if it has occurred.
3626 cache = &zone->uz_cpu[curcpu];
3627 bucket = &cache->uc_allocbucket;
3628 if (__predict_false(bucket->ucb_cnt == 0))
3629 return (cache_alloc_retry(zone, cache, udata, flags));
3630 return (cache_alloc_item(zone, cache, bucket, udata, flags));
3634 * Replenish an alloc bucket and possibly restore an old one. Called in
3635 * a critical section. Returns in a critical section.
3637 * A false return value indicates an allocation failure.
3638 * A true return value indicates success and the caller should retry.
3640 static __noinline bool
3641 cache_alloc(uma_zone_t zone, uma_cache_t cache, void *udata, int flags)
3643 uma_bucket_t bucket;
3644 int curdomain, domain;
3647 CRITICAL_ASSERT(curthread);
3650 * If we have run out of items in our alloc bucket see
3651 * if we can switch with the free bucket.
3653 * SMR Zones can't re-use the free bucket until the sequence has
3656 if ((cache_uz_flags(cache) & UMA_ZONE_SMR) == 0 &&
3657 cache->uc_freebucket.ucb_cnt != 0) {
3658 cache_bucket_swap(&cache->uc_freebucket,
3659 &cache->uc_allocbucket);
3664 * Discard any empty allocation bucket while we hold no locks.
3666 bucket = cache_bucket_unload_alloc(cache);
3669 if (bucket != NULL) {
3670 KASSERT(bucket->ub_cnt == 0,
3671 ("cache_alloc: Entered with non-empty alloc bucket."));
3672 bucket_free(zone, bucket, udata);
3676 * Attempt to retrieve the item from the per-CPU cache has failed, so
3677 * we must go back to the zone. This requires the zdom lock, so we
3678 * must drop the critical section, then re-acquire it when we go back
3679 * to the cache. Since the critical section is released, we may be
3680 * preempted or migrate. As such, make sure not to maintain any
3681 * thread-local state specific to the cache from prior to releasing
3682 * the critical section.
3684 domain = PCPU_GET(domain);
3685 if ((cache_uz_flags(cache) & UMA_ZONE_ROUNDROBIN) != 0 ||
3686 VM_DOMAIN_EMPTY(domain))
3687 domain = zone_domain_highest(zone, domain);
3688 bucket = cache_fetch_bucket(zone, cache, domain);
3689 if (bucket == NULL && zone->uz_bucket_size != 0 && !bucketdisable) {
3690 bucket = zone_alloc_bucket(zone, udata, domain, flags);
3696 CTR3(KTR_UMA, "uma_zalloc: zone %s(%p) bucket zone returned %p",
3697 zone->uz_name, zone, bucket);
3698 if (bucket == NULL) {
3704 * See if we lost the race or were migrated. Cache the
3705 * initialized bucket to make this less likely or claim
3706 * the memory directly.
3709 cache = &zone->uz_cpu[curcpu];
3710 if (cache->uc_allocbucket.ucb_bucket == NULL &&
3711 ((cache_uz_flags(cache) & UMA_ZONE_FIRSTTOUCH) == 0 ||
3712 (curdomain = PCPU_GET(domain)) == domain ||
3713 VM_DOMAIN_EMPTY(curdomain))) {
3715 atomic_add_long(&ZDOM_GET(zone, domain)->uzd_imax,
3717 cache_bucket_load_alloc(cache, bucket);
3722 * We lost the race, release this bucket and start over.
3725 zone_put_bucket(zone, domain, bucket, udata, !new);
3732 uma_zalloc_domain(uma_zone_t zone, void *udata, int domain, int flags)
3735 uma_bucket_t bucket;
3736 uma_zone_domain_t zdom;
3740 /* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
3741 random_harvest_fast_uma(&zone, sizeof(zone), RANDOM_UMA);
3743 /* This is the fast path allocation */
3744 CTR4(KTR_UMA, "uma_zalloc_domain zone %s(%p) domain %d flags %d",
3745 zone->uz_name, zone, domain, flags);
3747 if (flags & M_WAITOK) {
3748 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
3749 "uma_zalloc_domain: zone \"%s\"", zone->uz_name);
3751 KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
3752 ("uma_zalloc_domain: called with spinlock or critical section held"));
3753 KASSERT((zone->uz_flags & UMA_ZONE_SMR) == 0,
3754 ("uma_zalloc_domain: called with SMR zone."));
3756 KASSERT((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) != 0,
3757 ("uma_zalloc_domain: called with non-FIRSTTOUCH zone."));
3759 if (vm_ndomains == 1)
3760 return (uma_zalloc_arg(zone, udata, flags));
3763 * Try to allocate from the bucket cache before falling back to the keg.
3764 * We could try harder and attempt to allocate from per-CPU caches or
3765 * the per-domain cross-domain buckets, but the complexity is probably
3766 * not worth it. It is more important that frees of previous
3767 * cross-domain allocations do not blow up the cache.
3769 zdom = zone_domain_lock(zone, domain);
3770 if ((bucket = zone_fetch_bucket(zone, zdom, false)) != NULL) {
3771 item = bucket->ub_bucket[bucket->ub_cnt - 1];
3773 bucket->ub_bucket[bucket->ub_cnt - 1] = NULL;
3776 zone_put_bucket(zone, domain, bucket, udata, true);
3777 item = item_ctor(zone, zone->uz_flags, zone->uz_size, udata,
3780 KASSERT(item_domain(item) == domain,
3781 ("%s: bucket cache item %p from wrong domain",
3783 counter_u64_add(zone->uz_allocs, 1);
3788 return (zone_alloc_item(zone, udata, domain, flags));
3790 return (uma_zalloc_arg(zone, udata, flags));
3795 * Find a slab with some space. Prefer slabs that are partially used over those
3796 * that are totally full. This helps to reduce fragmentation.
3798 * If 'rr' is 1, search all domains starting from 'domain'. Otherwise check
3802 keg_first_slab(uma_keg_t keg, int domain, bool rr)
3808 KASSERT(domain >= 0 && domain < vm_ndomains,
3809 ("keg_first_slab: domain %d out of range", domain));
3810 KEG_LOCK_ASSERT(keg, domain);
3815 dom = &keg->uk_domain[domain];
3816 if ((slab = LIST_FIRST(&dom->ud_part_slab)) != NULL)
3818 if ((slab = LIST_FIRST(&dom->ud_free_slab)) != NULL) {
3819 LIST_REMOVE(slab, us_link);
3820 dom->ud_free_slabs--;
3821 LIST_INSERT_HEAD(&dom->ud_part_slab, slab, us_link);
3825 domain = (domain + 1) % vm_ndomains;
3826 } while (domain != start);
3832 * Fetch an existing slab from a free or partial list. Returns with the
3833 * keg domain lock held if a slab was found or unlocked if not.
3836 keg_fetch_free_slab(uma_keg_t keg, int domain, bool rr, int flags)
3841 /* HASH has a single free list. */
3842 if ((keg->uk_flags & UMA_ZFLAG_HASH) != 0)
3845 KEG_LOCK(keg, domain);
3846 reserve = (flags & M_USE_RESERVE) != 0 ? 0 : keg->uk_reserve;
3847 if (keg->uk_domain[domain].ud_free_items <= reserve ||
3848 (slab = keg_first_slab(keg, domain, rr)) == NULL) {
3849 KEG_UNLOCK(keg, domain);
3856 keg_fetch_slab(uma_keg_t keg, uma_zone_t zone, int rdomain, const int flags)
3858 struct vm_domainset_iter di;
3863 KASSERT((flags & (M_WAITOK | M_NOVM)) != (M_WAITOK | M_NOVM),
3864 ("%s: invalid flags %#x", __func__, flags));
3868 * Use the keg's policy if upper layers haven't already specified a
3869 * domain (as happens with first-touch zones).
3871 * To avoid races we run the iterator with the keg lock held, but that
3872 * means that we cannot allow the vm_domainset layer to sleep. Thus,
3873 * clear M_WAITOK and handle low memory conditions locally.
3875 rr = rdomain == UMA_ANYDOMAIN;
3877 aflags = (flags & ~M_WAITOK) | M_NOWAIT;
3878 vm_domainset_iter_policy_ref_init(&di, &keg->uk_dr, &domain,
3886 slab = keg_fetch_free_slab(keg, domain, rr, flags);
3891 * M_NOVM is used to break the recursion that can otherwise
3892 * occur if low-level memory management routines use UMA.
3894 if ((flags & M_NOVM) == 0) {
3895 slab = keg_alloc_slab(keg, zone, domain, flags, aflags);
3901 if ((flags & M_USE_RESERVE) != 0) {
3903 * Drain reserves from other domains before
3904 * giving up or sleeping. It may be useful to
3905 * support per-domain reserves eventually.
3907 rdomain = UMA_ANYDOMAIN;
3910 if ((flags & M_WAITOK) == 0)
3912 vm_wait_domain(domain);
3913 } else if (vm_domainset_iter_policy(&di, &domain) != 0) {
3914 if ((flags & M_WAITOK) != 0) {
3915 vm_wait_doms(&keg->uk_dr.dr_policy->ds_mask, 0);
3923 * We might not have been able to get a slab but another cpu
3924 * could have while we were unlocked. Check again before we
3927 if ((slab = keg_fetch_free_slab(keg, domain, rr, flags)) != NULL)
3934 slab_alloc_item(uma_keg_t keg, uma_slab_t slab)
3940 KEG_LOCK_ASSERT(keg, slab->us_domain);
3942 dom = &keg->uk_domain[slab->us_domain];
3943 freei = BIT_FFS(keg->uk_ipers, &slab->us_free) - 1;
3944 BIT_CLR(keg->uk_ipers, freei, &slab->us_free);
3945 item = slab_item(slab, keg, freei);
3946 slab->us_freecount--;
3947 dom->ud_free_items--;
3950 * Move this slab to the full list. It must be on the partial list, so
3951 * we do not need to update the free slab count. In particular,
3952 * keg_fetch_slab() always returns slabs on the partial list.
3954 if (slab->us_freecount == 0) {
3955 LIST_REMOVE(slab, us_link);
3956 LIST_INSERT_HEAD(&dom->ud_full_slab, slab, us_link);
3963 zone_import(void *arg, void **bucket, int max, int domain, int flags)
3977 /* Try to keep the buckets totally full */
3978 for (i = 0; i < max; ) {
3979 if ((slab = keg_fetch_slab(keg, zone, domain, flags)) == NULL)
3982 stripe = howmany(max, vm_ndomains);
3984 dom = &keg->uk_domain[slab->us_domain];
3986 bucket[i++] = slab_alloc_item(keg, slab);
3987 if (keg->uk_reserve > 0 &&
3988 dom->ud_free_items <= keg->uk_reserve) {
3990 * Avoid depleting the reserve after a
3991 * successful item allocation, even if
3992 * M_USE_RESERVE is specified.
3994 KEG_UNLOCK(keg, slab->us_domain);
3999 * If the zone is striped we pick a new slab for every
4000 * N allocations. Eliminating this conditional will
4001 * instead pick a new domain for each bucket rather
4002 * than stripe within each bucket. The current option
4003 * produces more fragmentation and requires more cpu
4004 * time but yields better distribution.
4006 if ((zone->uz_flags & UMA_ZONE_ROUNDROBIN) != 0 &&
4007 vm_ndomains > 1 && --stripe == 0)
4010 } while (slab->us_freecount != 0 && i < max);
4011 KEG_UNLOCK(keg, slab->us_domain);
4013 /* Don't block if we allocated any successfully. */
4022 zone_alloc_limit_hard(uma_zone_t zone, int count, int flags)
4024 uint64_t old, new, total, max;
4027 * The hard case. We're going to sleep because there were existing
4028 * sleepers or because we ran out of items. This routine enforces
4029 * fairness by keeping fifo order.
4031 * First release our ill gotten gains and make some noise.
4034 zone_free_limit(zone, count);
4035 zone_log_warning(zone);
4036 zone_maxaction(zone);
4037 if (flags & M_NOWAIT)
4041 * We need to allocate an item or set ourself as a sleeper
4042 * while the sleepq lock is held to avoid wakeup races. This
4043 * is essentially a home rolled semaphore.
4045 sleepq_lock(&zone->uz_max_items);
4046 old = zone->uz_items;
4048 MPASS(UZ_ITEMS_SLEEPERS(old) < UZ_ITEMS_SLEEPERS_MAX);
4049 /* Cache the max since we will evaluate twice. */
4050 max = zone->uz_max_items;
4051 if (UZ_ITEMS_SLEEPERS(old) != 0 ||
4052 UZ_ITEMS_COUNT(old) >= max)
4053 new = old + UZ_ITEMS_SLEEPER;
4055 new = old + MIN(count, max - old);
4056 } while (atomic_fcmpset_64(&zone->uz_items, &old, new) == 0);
4058 /* We may have successfully allocated under the sleepq lock. */
4059 if (UZ_ITEMS_SLEEPERS(new) == 0) {
4060 sleepq_release(&zone->uz_max_items);
4065 * This is in a different cacheline from uz_items so that we
4066 * don't constantly invalidate the fastpath cacheline when we
4067 * adjust item counts. This could be limited to toggling on
4070 atomic_add_32(&zone->uz_sleepers, 1);
4071 atomic_add_64(&zone->uz_sleeps, 1);
4074 * We have added ourselves as a sleeper. The sleepq lock
4075 * protects us from wakeup races. Sleep now and then retry.
4077 sleepq_add(&zone->uz_max_items, NULL, "zonelimit", 0, 0);
4078 sleepq_wait(&zone->uz_max_items, PVM);
4081 * After wakeup, remove ourselves as a sleeper and try
4082 * again. We no longer have the sleepq lock for protection.
4084 * Subract ourselves as a sleeper while attempting to add
4087 atomic_subtract_32(&zone->uz_sleepers, 1);
4088 old = atomic_fetchadd_64(&zone->uz_items,
4089 -(UZ_ITEMS_SLEEPER - count));
4090 /* We're no longer a sleeper. */
4091 old -= UZ_ITEMS_SLEEPER;
4094 * If we're still at the limit, restart. Notably do not
4095 * block on other sleepers. Cache the max value to protect
4096 * against changes via sysctl.
4098 total = UZ_ITEMS_COUNT(old);
4099 max = zone->uz_max_items;
4102 /* Truncate if necessary, otherwise wake other sleepers. */
4103 if (total + count > max) {
4104 zone_free_limit(zone, total + count - max);
4105 count = max - total;
4106 } else if (total + count < max && UZ_ITEMS_SLEEPERS(old) != 0)
4107 wakeup_one(&zone->uz_max_items);
4114 * Allocate 'count' items from our max_items limit. Returns the number
4115 * available. If M_NOWAIT is not specified it will sleep until at least
4116 * one item can be allocated.
4119 zone_alloc_limit(uma_zone_t zone, int count, int flags)
4124 max = zone->uz_max_items;
4128 * We expect normal allocations to succeed with a simple
4131 old = atomic_fetchadd_64(&zone->uz_items, count);
4132 if (__predict_true(old + count <= max))
4136 * If we had some items and no sleepers just return the
4137 * truncated value. We have to release the excess space
4138 * though because that may wake sleepers who weren't woken
4139 * because we were temporarily over the limit.
4142 zone_free_limit(zone, (old + count) - max);
4145 return (zone_alloc_limit_hard(zone, count, flags));
4149 * Free a number of items back to the limit.
4152 zone_free_limit(uma_zone_t zone, int count)
4159 * In the common case we either have no sleepers or
4160 * are still over the limit and can just return.
4162 old = atomic_fetchadd_64(&zone->uz_items, -count);
4163 if (__predict_true(UZ_ITEMS_SLEEPERS(old) == 0 ||
4164 UZ_ITEMS_COUNT(old) - count >= zone->uz_max_items))
4168 * Moderate the rate of wakeups. Sleepers will continue
4169 * to generate wakeups if necessary.
4171 wakeup_one(&zone->uz_max_items);
4175 zone_alloc_bucket(uma_zone_t zone, void *udata, int domain, int flags)
4177 uma_bucket_t bucket;
4178 int error, maxbucket, cnt;
4180 CTR3(KTR_UMA, "zone_alloc_bucket zone %s(%p) domain %d", zone->uz_name,
4183 /* Avoid allocs targeting empty domains. */
4184 if (domain != UMA_ANYDOMAIN && VM_DOMAIN_EMPTY(domain))
4185 domain = UMA_ANYDOMAIN;
4186 else if ((zone->uz_flags & UMA_ZONE_ROUNDROBIN) != 0)
4187 domain = UMA_ANYDOMAIN;
4189 if (zone->uz_max_items > 0)
4190 maxbucket = zone_alloc_limit(zone, zone->uz_bucket_size,
4193 maxbucket = zone->uz_bucket_size;
4197 /* Don't wait for buckets, preserve caller's NOVM setting. */
4198 bucket = bucket_alloc(zone, udata, M_NOWAIT | (flags & M_NOVM));
4199 if (bucket == NULL) {
4204 bucket->ub_cnt = zone->uz_import(zone->uz_arg, bucket->ub_bucket,
4205 MIN(maxbucket, bucket->ub_entries), domain, flags);
4208 * Initialize the memory if necessary.
4210 if (bucket->ub_cnt != 0 && zone->uz_init != NULL) {
4213 for (i = 0; i < bucket->ub_cnt; i++) {
4214 kasan_mark_item_valid(zone, bucket->ub_bucket[i]);
4215 error = zone->uz_init(bucket->ub_bucket[i],
4216 zone->uz_size, flags);
4217 kasan_mark_item_invalid(zone, bucket->ub_bucket[i]);
4223 * If we couldn't initialize the whole bucket, put the
4224 * rest back onto the freelist.
4226 if (i != bucket->ub_cnt) {
4227 zone->uz_release(zone->uz_arg, &bucket->ub_bucket[i],
4228 bucket->ub_cnt - i);
4230 bzero(&bucket->ub_bucket[i],
4231 sizeof(void *) * (bucket->ub_cnt - i));
4237 cnt = bucket->ub_cnt;
4238 if (bucket->ub_cnt == 0) {
4239 bucket_free(zone, bucket, udata);
4240 counter_u64_add(zone->uz_fails, 1);
4244 if (zone->uz_max_items > 0 && cnt < maxbucket)
4245 zone_free_limit(zone, maxbucket - cnt);
4251 * Allocates a single item from a zone.
4254 * zone The zone to alloc for.
4255 * udata The data to be passed to the constructor.
4256 * domain The domain to allocate from or UMA_ANYDOMAIN.
4257 * flags M_WAITOK, M_NOWAIT, M_ZERO.
4260 * NULL if there is no memory and M_NOWAIT is set
4261 * An item if successful
4265 zone_alloc_item(uma_zone_t zone, void *udata, int domain, int flags)
4269 if (zone->uz_max_items > 0 && zone_alloc_limit(zone, 1, flags) == 0) {
4270 counter_u64_add(zone->uz_fails, 1);
4274 /* Avoid allocs targeting empty domains. */
4275 if (domain != UMA_ANYDOMAIN && VM_DOMAIN_EMPTY(domain))
4276 domain = UMA_ANYDOMAIN;
4278 if (zone->uz_import(zone->uz_arg, &item, 1, domain, flags) != 1)
4282 * We have to call both the zone's init (not the keg's init)
4283 * and the zone's ctor. This is because the item is going from
4284 * a keg slab directly to the user, and the user is expecting it
4285 * to be both zone-init'd as well as zone-ctor'd.
4287 if (zone->uz_init != NULL) {
4290 kasan_mark_item_valid(zone, item);
4291 error = zone->uz_init(item, zone->uz_size, flags);
4292 kasan_mark_item_invalid(zone, item);
4294 zone_free_item(zone, item, udata, SKIP_FINI | SKIP_CNT);
4298 item = item_ctor(zone, zone->uz_flags, zone->uz_size, udata, flags,
4303 counter_u64_add(zone->uz_allocs, 1);
4304 CTR3(KTR_UMA, "zone_alloc_item item %p from %s(%p)", item,
4305 zone->uz_name, zone);
4310 counter_u64_add(zone->uz_fails, 1);
4312 if (zone->uz_max_items > 0)
4313 zone_free_limit(zone, 1);
4314 CTR2(KTR_UMA, "zone_alloc_item failed from %s(%p)",
4315 zone->uz_name, zone);
4322 uma_zfree_smr(uma_zone_t zone, void *item)
4325 uma_cache_bucket_t bucket;
4326 int itemdomain, uz_flags;
4328 #ifdef UMA_ZALLOC_DEBUG
4329 KASSERT((zone->uz_flags & UMA_ZONE_SMR) != 0,
4330 ("uma_zfree_smr: called with non-SMR zone."));
4331 KASSERT(item != NULL, ("uma_zfree_smr: Called with NULL pointer."));
4332 SMR_ASSERT_NOT_ENTERED(zone->uz_smr);
4333 if (uma_zfree_debug(zone, item, NULL) == EJUSTRETURN)
4336 cache = &zone->uz_cpu[curcpu];
4337 uz_flags = cache_uz_flags(cache);
4340 if ((uz_flags & UMA_ZONE_FIRSTTOUCH) != 0)
4341 itemdomain = item_domain(item);
4345 cache = &zone->uz_cpu[curcpu];
4346 /* SMR Zones must free to the free bucket. */
4347 bucket = &cache->uc_freebucket;
4349 if ((uz_flags & UMA_ZONE_FIRSTTOUCH) != 0 &&
4350 PCPU_GET(domain) != itemdomain) {
4351 bucket = &cache->uc_crossbucket;
4354 if (__predict_true(bucket->ucb_cnt < bucket->ucb_entries)) {
4355 cache_bucket_push(cache, bucket, item);
4359 } while (cache_free(zone, cache, NULL, item, itemdomain));
4363 * If nothing else caught this, we'll just do an internal free.
4365 zone_free_item(zone, item, NULL, SKIP_NONE);
4370 uma_zfree_arg(uma_zone_t zone, void *item, void *udata)
4373 uma_cache_bucket_t bucket;
4374 int itemdomain, uz_flags;
4376 /* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
4377 random_harvest_fast_uma(&zone, sizeof(zone), RANDOM_UMA);
4379 CTR2(KTR_UMA, "uma_zfree_arg zone %s(%p)", zone->uz_name, zone);
4381 #ifdef UMA_ZALLOC_DEBUG
4382 KASSERT((zone->uz_flags & UMA_ZONE_SMR) == 0,
4383 ("uma_zfree_arg: called with SMR zone."));
4384 if (uma_zfree_debug(zone, item, udata) == EJUSTRETURN)
4387 /* uma_zfree(..., NULL) does nothing, to match free(9). */
4392 * We are accessing the per-cpu cache without a critical section to
4393 * fetch size and flags. This is acceptable, if we are preempted we
4394 * will simply read another cpu's line.
4396 cache = &zone->uz_cpu[curcpu];
4397 uz_flags = cache_uz_flags(cache);
4398 if (UMA_ALWAYS_CTORDTOR ||
4399 __predict_false((uz_flags & UMA_ZFLAG_CTORDTOR) != 0))
4400 item_dtor(zone, item, cache_uz_size(cache), udata, SKIP_NONE);
4403 * The race here is acceptable. If we miss it we'll just have to wait
4404 * a little longer for the limits to be reset.
4406 if (__predict_false(uz_flags & UMA_ZFLAG_LIMIT)) {
4407 if (atomic_load_32(&zone->uz_sleepers) > 0)
4412 * If possible, free to the per-CPU cache. There are two
4413 * requirements for safe access to the per-CPU cache: (1) the thread
4414 * accessing the cache must not be preempted or yield during access,
4415 * and (2) the thread must not migrate CPUs without switching which
4416 * cache it accesses. We rely on a critical section to prevent
4417 * preemption and migration. We release the critical section in
4418 * order to acquire the zone mutex if we are unable to free to the
4419 * current cache; when we re-acquire the critical section, we must
4420 * detect and handle migration if it has occurred.
4424 if ((uz_flags & UMA_ZONE_FIRSTTOUCH) != 0)
4425 itemdomain = item_domain(item);
4429 cache = &zone->uz_cpu[curcpu];
4431 * Try to free into the allocbucket first to give LIFO
4432 * ordering for cache-hot datastructures. Spill over
4433 * into the freebucket if necessary. Alloc will swap
4434 * them if one runs dry.
4436 bucket = &cache->uc_allocbucket;
4438 if ((uz_flags & UMA_ZONE_FIRSTTOUCH) != 0 &&
4439 PCPU_GET(domain) != itemdomain) {
4440 bucket = &cache->uc_crossbucket;
4443 if (bucket->ucb_cnt == bucket->ucb_entries &&
4444 cache->uc_freebucket.ucb_cnt <
4445 cache->uc_freebucket.ucb_entries)
4446 cache_bucket_swap(&cache->uc_freebucket,
4447 &cache->uc_allocbucket);
4448 if (__predict_true(bucket->ucb_cnt < bucket->ucb_entries)) {
4449 cache_bucket_push(cache, bucket, item);
4453 } while (cache_free(zone, cache, udata, item, itemdomain));
4457 * If nothing else caught this, we'll just do an internal free.
4460 zone_free_item(zone, item, udata, SKIP_DTOR);
4465 * sort crossdomain free buckets to domain correct buckets and cache
4469 zone_free_cross(uma_zone_t zone, uma_bucket_t bucket, void *udata)
4471 struct uma_bucketlist emptybuckets, fullbuckets;
4472 uma_zone_domain_t zdom;
4479 "uma_zfree: zone %s(%p) draining cross bucket %p",
4480 zone->uz_name, zone, bucket);
4483 * It is possible for buckets to arrive here out of order so we fetch
4484 * the current smr seq rather than accepting the bucket's.
4486 seq = SMR_SEQ_INVALID;
4487 if ((zone->uz_flags & UMA_ZONE_SMR) != 0)
4488 seq = smr_advance(zone->uz_smr);
4491 * To avoid having ndomain * ndomain buckets for sorting we have a
4492 * lock on the current crossfree bucket. A full matrix with
4493 * per-domain locking could be used if necessary.
4495 STAILQ_INIT(&emptybuckets);
4496 STAILQ_INIT(&fullbuckets);
4497 ZONE_CROSS_LOCK(zone);
4498 for (; bucket->ub_cnt > 0; bucket->ub_cnt--) {
4499 item = bucket->ub_bucket[bucket->ub_cnt - 1];
4500 domain = item_domain(item);
4501 zdom = ZDOM_GET(zone, domain);
4502 if (zdom->uzd_cross == NULL) {
4503 if ((b = STAILQ_FIRST(&emptybuckets)) != NULL) {
4504 STAILQ_REMOVE_HEAD(&emptybuckets, ub_link);
4505 zdom->uzd_cross = b;
4508 * Avoid allocating a bucket with the cross lock
4509 * held, since allocation can trigger a
4510 * cross-domain free and bucket zones may
4511 * allocate from each other.
4513 ZONE_CROSS_UNLOCK(zone);
4514 b = bucket_alloc(zone, udata, M_NOWAIT);
4517 ZONE_CROSS_LOCK(zone);
4518 if (zdom->uzd_cross != NULL) {
4519 STAILQ_INSERT_HEAD(&emptybuckets, b,
4522 zdom->uzd_cross = b;
4526 b = zdom->uzd_cross;
4527 b->ub_bucket[b->ub_cnt++] = item;
4529 if (b->ub_cnt == b->ub_entries) {
4530 STAILQ_INSERT_HEAD(&fullbuckets, b, ub_link);
4531 if ((b = STAILQ_FIRST(&emptybuckets)) != NULL)
4532 STAILQ_REMOVE_HEAD(&emptybuckets, ub_link);
4533 zdom->uzd_cross = b;
4536 ZONE_CROSS_UNLOCK(zone);
4538 if (bucket->ub_cnt == 0)
4539 bucket->ub_seq = SMR_SEQ_INVALID;
4540 bucket_free(zone, bucket, udata);
4542 while ((b = STAILQ_FIRST(&emptybuckets)) != NULL) {
4543 STAILQ_REMOVE_HEAD(&emptybuckets, ub_link);
4544 bucket_free(zone, b, udata);
4546 while ((b = STAILQ_FIRST(&fullbuckets)) != NULL) {
4547 STAILQ_REMOVE_HEAD(&fullbuckets, ub_link);
4548 domain = item_domain(b->ub_bucket[0]);
4549 zone_put_bucket(zone, domain, b, udata, true);
4555 zone_free_bucket(uma_zone_t zone, uma_bucket_t bucket, void *udata,
4556 int itemdomain, bool ws)
4561 * Buckets coming from the wrong domain will be entirely for the
4562 * only other domain on two domain systems. In this case we can
4563 * simply cache them. Otherwise we need to sort them back to
4566 if ((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) != 0 &&
4567 vm_ndomains > 2 && PCPU_GET(domain) != itemdomain) {
4568 zone_free_cross(zone, bucket, udata);
4574 * Attempt to save the bucket in the zone's domain bucket cache.
4577 "uma_zfree: zone %s(%p) putting bucket %p on free list",
4578 zone->uz_name, zone, bucket);
4579 /* ub_cnt is pointing to the last free item */
4580 if ((zone->uz_flags & UMA_ZONE_ROUNDROBIN) != 0)
4581 itemdomain = zone_domain_lowest(zone, itemdomain);
4582 zone_put_bucket(zone, itemdomain, bucket, udata, ws);
4586 * Populate a free or cross bucket for the current cpu cache. Free any
4587 * existing full bucket either to the zone cache or back to the slab layer.
4589 * Enters and returns in a critical section. false return indicates that
4590 * we can not satisfy this free in the cache layer. true indicates that
4591 * the caller should retry.
4593 static __noinline bool
4594 cache_free(uma_zone_t zone, uma_cache_t cache, void *udata, void *item,
4597 uma_cache_bucket_t cbucket;
4598 uma_bucket_t newbucket, bucket;
4600 CRITICAL_ASSERT(curthread);
4602 if (zone->uz_bucket_size == 0)
4605 cache = &zone->uz_cpu[curcpu];
4609 * FIRSTTOUCH domains need to free to the correct zdom. When
4610 * enabled this is the zdom of the item. The bucket is the
4611 * cross bucket if the current domain and itemdomain do not match.
4613 cbucket = &cache->uc_freebucket;
4615 if ((cache_uz_flags(cache) & UMA_ZONE_FIRSTTOUCH) != 0) {
4616 if (PCPU_GET(domain) != itemdomain) {
4617 cbucket = &cache->uc_crossbucket;
4618 if (cbucket->ucb_cnt != 0)
4619 counter_u64_add(zone->uz_xdomain,
4624 bucket = cache_bucket_unload(cbucket);
4625 KASSERT(bucket == NULL || bucket->ub_cnt == bucket->ub_entries,
4626 ("cache_free: Entered with non-full free bucket."));
4628 /* We are no longer associated with this CPU. */
4632 * Don't let SMR zones operate without a free bucket. Force
4633 * a synchronize and re-use this one. We will only degrade
4634 * to a synchronize every bucket_size items rather than every
4635 * item if we fail to allocate a bucket.
4637 if ((zone->uz_flags & UMA_ZONE_SMR) != 0) {
4639 bucket->ub_seq = smr_advance(zone->uz_smr);
4640 newbucket = bucket_alloc(zone, udata, M_NOWAIT);
4641 if (newbucket == NULL && bucket != NULL) {
4642 bucket_drain(zone, bucket);
4646 } else if (!bucketdisable)
4647 newbucket = bucket_alloc(zone, udata, M_NOWAIT);
4650 zone_free_bucket(zone, bucket, udata, itemdomain, true);
4653 if ((bucket = newbucket) == NULL)
4655 cache = &zone->uz_cpu[curcpu];
4658 * Check to see if we should be populating the cross bucket. If it
4659 * is already populated we will fall through and attempt to populate
4662 if ((cache_uz_flags(cache) & UMA_ZONE_FIRSTTOUCH) != 0) {
4663 if (PCPU_GET(domain) != itemdomain &&
4664 cache->uc_crossbucket.ucb_bucket == NULL) {
4665 cache_bucket_load_cross(cache, bucket);
4671 * We may have lost the race to fill the bucket or switched CPUs.
4673 if (cache->uc_freebucket.ucb_bucket != NULL) {
4675 bucket_free(zone, bucket, udata);
4678 cache_bucket_load_free(cache, bucket);
4684 slab_free_item(uma_zone_t zone, uma_slab_t slab, void *item)
4691 KEG_LOCK_ASSERT(keg, slab->us_domain);
4693 /* Do we need to remove from any lists? */
4694 dom = &keg->uk_domain[slab->us_domain];
4695 if (slab->us_freecount + 1 == keg->uk_ipers) {
4696 LIST_REMOVE(slab, us_link);
4697 LIST_INSERT_HEAD(&dom->ud_free_slab, slab, us_link);
4698 dom->ud_free_slabs++;
4699 } else if (slab->us_freecount == 0) {
4700 LIST_REMOVE(slab, us_link);
4701 LIST_INSERT_HEAD(&dom->ud_part_slab, slab, us_link);
4704 /* Slab management. */
4705 freei = slab_item_index(slab, keg, item);
4706 BIT_SET(keg->uk_ipers, freei, &slab->us_free);
4707 slab->us_freecount++;
4709 /* Keg statistics. */
4710 dom->ud_free_items++;
4714 zone_release(void *arg, void **bucket, int cnt)
4727 if (__predict_false((zone->uz_flags & UMA_ZFLAG_HASH) != 0))
4728 lock = KEG_LOCK(keg, 0);
4729 for (i = 0; i < cnt; i++) {
4731 if (__predict_true((zone->uz_flags & UMA_ZFLAG_VTOSLAB) != 0)) {
4732 slab = vtoslab((vm_offset_t)item);
4734 mem = (uint8_t *)((uintptr_t)item & (~UMA_SLAB_MASK));
4735 if ((zone->uz_flags & UMA_ZFLAG_HASH) != 0)
4736 slab = hash_sfind(&keg->uk_hash, mem);
4738 slab = (uma_slab_t)(mem + keg->uk_pgoff);
4740 if (lock != KEG_LOCKPTR(keg, slab->us_domain)) {
4743 lock = KEG_LOCK(keg, slab->us_domain);
4745 slab_free_item(zone, slab, item);
4752 * Frees a single item to any zone.
4755 * zone The zone to free to
4756 * item The item we're freeing
4757 * udata User supplied data for the dtor
4758 * skip Skip dtors and finis
4760 static __noinline void
4761 zone_free_item(uma_zone_t zone, void *item, void *udata, enum zfreeskip skip)
4765 * If a free is sent directly to an SMR zone we have to
4766 * synchronize immediately because the item can instantly
4767 * be reallocated. This should only happen in degenerate
4768 * cases when no memory is available for per-cpu caches.
4770 if ((zone->uz_flags & UMA_ZONE_SMR) != 0 && skip == SKIP_NONE)
4771 smr_synchronize(zone->uz_smr);
4773 item_dtor(zone, item, zone->uz_size, udata, skip);
4775 if (skip < SKIP_FINI && zone->uz_fini) {
4776 kasan_mark_item_valid(zone, item);
4777 zone->uz_fini(item, zone->uz_size);
4778 kasan_mark_item_invalid(zone, item);
4781 zone->uz_release(zone->uz_arg, &item, 1);
4783 if (skip & SKIP_CNT)
4786 counter_u64_add(zone->uz_frees, 1);
4788 if (zone->uz_max_items > 0)
4789 zone_free_limit(zone, 1);
4794 uma_zone_set_max(uma_zone_t zone, int nitems)
4798 * If the limit is small, we may need to constrain the maximum per-CPU
4799 * cache size, or disable caching entirely.
4801 uma_zone_set_maxcache(zone, nitems);
4804 * XXX This can misbehave if the zone has any allocations with
4805 * no limit and a limit is imposed. There is currently no
4806 * way to clear a limit.
4809 zone->uz_max_items = nitems;
4810 zone->uz_flags |= UMA_ZFLAG_LIMIT;
4811 zone_update_caches(zone);
4812 /* We may need to wake waiters. */
4813 wakeup(&zone->uz_max_items);
4821 uma_zone_set_maxcache(uma_zone_t zone, int nitems)
4823 int bpcpu, bpdom, bsize, nb;
4828 * Compute a lower bound on the number of items that may be cached in
4829 * the zone. Each CPU gets at least two buckets, and for cross-domain
4830 * frees we use an additional bucket per CPU and per domain. Select the
4831 * largest bucket size that does not exceed half of the requested limit,
4832 * with the left over space given to the full bucket cache.
4837 if ((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) != 0 && vm_ndomains > 1) {
4842 nb = bpcpu * mp_ncpus + bpdom * vm_ndomains;
4843 bsize = nitems / nb / 2;
4844 if (bsize > BUCKET_MAX)
4846 else if (bsize == 0 && nitems / nb > 0)
4848 zone->uz_bucket_size_max = zone->uz_bucket_size = bsize;
4849 if (zone->uz_bucket_size_min > zone->uz_bucket_size_max)
4850 zone->uz_bucket_size_min = zone->uz_bucket_size_max;
4851 zone->uz_bucket_max = nitems - nb * bsize;
4857 uma_zone_get_max(uma_zone_t zone)
4861 nitems = atomic_load_64(&zone->uz_max_items);
4868 uma_zone_set_warning(uma_zone_t zone, const char *warning)
4871 ZONE_ASSERT_COLD(zone);
4872 zone->uz_warning = warning;
4877 uma_zone_set_maxaction(uma_zone_t zone, uma_maxaction_t maxaction)
4880 ZONE_ASSERT_COLD(zone);
4881 TASK_INIT(&zone->uz_maxaction, 0, (task_fn_t *)maxaction, zone);
4886 uma_zone_get_cur(uma_zone_t zone)
4892 if (zone->uz_allocs != EARLY_COUNTER && zone->uz_frees != EARLY_COUNTER)
4893 nitems = counter_u64_fetch(zone->uz_allocs) -
4894 counter_u64_fetch(zone->uz_frees);
4896 nitems += atomic_load_64(&zone->uz_cpu[i].uc_allocs) -
4897 atomic_load_64(&zone->uz_cpu[i].uc_frees);
4899 return (nitems < 0 ? 0 : nitems);
4903 uma_zone_get_allocs(uma_zone_t zone)
4909 if (zone->uz_allocs != EARLY_COUNTER)
4910 nitems = counter_u64_fetch(zone->uz_allocs);
4912 nitems += atomic_load_64(&zone->uz_cpu[i].uc_allocs);
4918 uma_zone_get_frees(uma_zone_t zone)
4924 if (zone->uz_frees != EARLY_COUNTER)
4925 nitems = counter_u64_fetch(zone->uz_frees);
4927 nitems += atomic_load_64(&zone->uz_cpu[i].uc_frees);
4933 /* Used only for KEG_ASSERT_COLD(). */
4935 uma_keg_get_allocs(uma_keg_t keg)
4941 LIST_FOREACH(z, &keg->uk_zones, uz_link)
4942 nitems += uma_zone_get_allocs(z);
4950 uma_zone_set_init(uma_zone_t zone, uma_init uminit)
4955 KEG_ASSERT_COLD(keg);
4956 keg->uk_init = uminit;
4961 uma_zone_set_fini(uma_zone_t zone, uma_fini fini)
4966 KEG_ASSERT_COLD(keg);
4967 keg->uk_fini = fini;
4972 uma_zone_set_zinit(uma_zone_t zone, uma_init zinit)
4975 ZONE_ASSERT_COLD(zone);
4976 zone->uz_init = zinit;
4981 uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini)
4984 ZONE_ASSERT_COLD(zone);
4985 zone->uz_fini = zfini;
4990 uma_zone_set_freef(uma_zone_t zone, uma_free freef)
4995 KEG_ASSERT_COLD(keg);
4996 keg->uk_freef = freef;
5001 uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf)
5006 KEG_ASSERT_COLD(keg);
5007 keg->uk_allocf = allocf;
5012 uma_zone_set_smr(uma_zone_t zone, smr_t smr)
5015 ZONE_ASSERT_COLD(zone);
5017 KASSERT(smr != NULL, ("Got NULL smr"));
5018 KASSERT((zone->uz_flags & UMA_ZONE_SMR) == 0,
5019 ("zone %p (%s) already uses SMR", zone, zone->uz_name));
5020 zone->uz_flags |= UMA_ZONE_SMR;
5022 zone_update_caches(zone);
5026 uma_zone_get_smr(uma_zone_t zone)
5029 return (zone->uz_smr);
5034 uma_zone_reserve(uma_zone_t zone, int items)
5039 KEG_ASSERT_COLD(keg);
5040 keg->uk_reserve = items;
5045 uma_zone_reserve_kva(uma_zone_t zone, int count)
5052 KEG_ASSERT_COLD(keg);
5053 ZONE_ASSERT_COLD(zone);
5055 pages = howmany(count, keg->uk_ipers) * keg->uk_ppera;
5057 #ifdef UMA_MD_SMALL_ALLOC
5058 if (keg->uk_ppera > 1) {
5062 kva = kva_alloc((vm_size_t)pages * PAGE_SIZE);
5068 MPASS(keg->uk_kva == 0);
5071 zone->uz_max_items = pages * keg->uk_ipers;
5072 #ifdef UMA_MD_SMALL_ALLOC
5073 keg->uk_allocf = (keg->uk_ppera > 1) ? noobj_alloc : uma_small_alloc;
5075 keg->uk_allocf = noobj_alloc;
5077 keg->uk_flags |= UMA_ZFLAG_LIMIT | UMA_ZONE_NOFREE;
5078 zone->uz_flags |= UMA_ZFLAG_LIMIT | UMA_ZONE_NOFREE;
5079 zone_update_caches(zone);
5086 uma_prealloc(uma_zone_t zone, int items)
5088 struct vm_domainset_iter di;
5092 int aflags, domain, slabs;
5095 slabs = howmany(items, keg->uk_ipers);
5096 while (slabs-- > 0) {
5098 vm_domainset_iter_policy_ref_init(&di, &keg->uk_dr, &domain,
5101 slab = keg_alloc_slab(keg, zone, domain, M_WAITOK,
5104 dom = &keg->uk_domain[slab->us_domain];
5106 * keg_alloc_slab() always returns a slab on the
5109 LIST_REMOVE(slab, us_link);
5110 LIST_INSERT_HEAD(&dom->ud_free_slab, slab,
5112 dom->ud_free_slabs++;
5113 KEG_UNLOCK(keg, slab->us_domain);
5116 if (vm_domainset_iter_policy(&di, &domain) != 0)
5117 vm_wait_doms(&keg->uk_dr.dr_policy->ds_mask, 0);
5123 * Returns a snapshot of memory consumption in bytes.
5126 uma_zone_memory(uma_zone_t zone)
5132 if (zone->uz_flags & UMA_ZFLAG_CACHE) {
5133 for (i = 0; i < vm_ndomains; i++)
5134 sz += ZDOM_GET(zone, i)->uzd_nitems;
5135 return (sz * zone->uz_size);
5137 for (i = 0; i < vm_ndomains; i++)
5138 sz += zone->uz_keg->uk_domain[i].ud_pages;
5140 return (sz * PAGE_SIZE);
5145 uma_reclaim(int req)
5147 uma_reclaim_domain(req, UMA_ANYDOMAIN);
5151 uma_reclaim_domain(int req, int domain)
5157 arg = (void *)(uintptr_t)domain;
5158 sx_slock(&uma_reclaim_lock);
5160 case UMA_RECLAIM_TRIM:
5161 zone_foreach(zone_trim, arg);
5163 case UMA_RECLAIM_DRAIN:
5164 zone_foreach(zone_drain, arg);
5166 case UMA_RECLAIM_DRAIN_CPU:
5167 zone_foreach(zone_drain, arg);
5168 pcpu_cache_drain_safe(NULL);
5169 zone_foreach(zone_drain, arg);
5172 panic("unhandled reclamation request %d", req);
5176 * Some slabs may have been freed but this zone will be visited early
5177 * we visit again so that we can free pages that are empty once other
5178 * zones are drained. We have to do the same for buckets.
5180 zone_drain(slabzones[0], arg);
5181 zone_drain(slabzones[1], arg);
5182 bucket_zone_drain(domain);
5183 sx_sunlock(&uma_reclaim_lock);
5186 static volatile int uma_reclaim_needed;
5189 uma_reclaim_wakeup(void)
5192 if (atomic_fetchadd_int(&uma_reclaim_needed, 1) == 0)
5193 wakeup(uma_reclaim);
5197 uma_reclaim_worker(void *arg __unused)
5201 sx_xlock(&uma_reclaim_lock);
5202 while (atomic_load_int(&uma_reclaim_needed) == 0)
5203 sx_sleep(uma_reclaim, &uma_reclaim_lock, PVM, "umarcl",
5205 sx_xunlock(&uma_reclaim_lock);
5206 EVENTHANDLER_INVOKE(vm_lowmem, VM_LOW_KMEM);
5207 uma_reclaim(UMA_RECLAIM_DRAIN_CPU);
5208 atomic_store_int(&uma_reclaim_needed, 0);
5209 /* Don't fire more than once per-second. */
5210 pause("umarclslp", hz);
5216 uma_zone_reclaim(uma_zone_t zone, int req)
5218 uma_zone_reclaim_domain(zone, req, UMA_ANYDOMAIN);
5222 uma_zone_reclaim_domain(uma_zone_t zone, int req, int domain)
5226 arg = (void *)(uintptr_t)domain;
5228 case UMA_RECLAIM_TRIM:
5229 zone_trim(zone, arg);
5231 case UMA_RECLAIM_DRAIN:
5232 zone_drain(zone, arg);
5234 case UMA_RECLAIM_DRAIN_CPU:
5235 pcpu_cache_drain_safe(zone);
5236 zone_drain(zone, arg);
5239 panic("unhandled reclamation request %d", req);
5245 uma_zone_exhausted(uma_zone_t zone)
5248 return (atomic_load_32(&zone->uz_sleepers) > 0);
5255 return (uma_kmem_limit);
5259 uma_set_limit(unsigned long limit)
5262 uma_kmem_limit = limit;
5269 return (atomic_load_long(&uma_kmem_total));
5276 return (uma_kmem_limit - uma_size());
5281 * Generate statistics across both the zone and its per-cpu cache's. Return
5282 * desired statistics if the pointer is non-NULL for that statistic.
5284 * Note: does not update the zone statistics, as it can't safely clear the
5285 * per-CPU cache statistic.
5289 uma_zone_sumstat(uma_zone_t z, long *cachefreep, uint64_t *allocsp,
5290 uint64_t *freesp, uint64_t *sleepsp, uint64_t *xdomainp)
5293 uint64_t allocs, frees, sleeps, xdomain;
5296 allocs = frees = sleeps = xdomain = 0;
5299 cache = &z->uz_cpu[cpu];
5300 cachefree += cache->uc_allocbucket.ucb_cnt;
5301 cachefree += cache->uc_freebucket.ucb_cnt;
5302 xdomain += cache->uc_crossbucket.ucb_cnt;
5303 cachefree += cache->uc_crossbucket.ucb_cnt;
5304 allocs += cache->uc_allocs;
5305 frees += cache->uc_frees;
5307 allocs += counter_u64_fetch(z->uz_allocs);
5308 frees += counter_u64_fetch(z->uz_frees);
5309 xdomain += counter_u64_fetch(z->uz_xdomain);
5310 sleeps += z->uz_sleeps;
5311 if (cachefreep != NULL)
5312 *cachefreep = cachefree;
5313 if (allocsp != NULL)
5317 if (sleepsp != NULL)
5319 if (xdomainp != NULL)
5320 *xdomainp = xdomain;
5325 sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS)
5332 rw_rlock(&uma_rwlock);
5333 LIST_FOREACH(kz, &uma_kegs, uk_link) {
5334 LIST_FOREACH(z, &kz->uk_zones, uz_link)
5337 LIST_FOREACH(z, &uma_cachezones, uz_link)
5340 rw_runlock(&uma_rwlock);
5341 return (sysctl_handle_int(oidp, &count, 0, req));
5345 uma_vm_zone_stats(struct uma_type_header *uth, uma_zone_t z, struct sbuf *sbuf,
5346 struct uma_percpu_stat *ups, bool internal)
5348 uma_zone_domain_t zdom;
5352 for (i = 0; i < vm_ndomains; i++) {
5353 zdom = ZDOM_GET(z, i);
5354 uth->uth_zone_free += zdom->uzd_nitems;
5356 uth->uth_allocs = counter_u64_fetch(z->uz_allocs);
5357 uth->uth_frees = counter_u64_fetch(z->uz_frees);
5358 uth->uth_fails = counter_u64_fetch(z->uz_fails);
5359 uth->uth_xdomain = counter_u64_fetch(z->uz_xdomain);
5360 uth->uth_sleeps = z->uz_sleeps;
5362 for (i = 0; i < mp_maxid + 1; i++) {
5363 bzero(&ups[i], sizeof(*ups));
5364 if (internal || CPU_ABSENT(i))
5366 cache = &z->uz_cpu[i];
5367 ups[i].ups_cache_free += cache->uc_allocbucket.ucb_cnt;
5368 ups[i].ups_cache_free += cache->uc_freebucket.ucb_cnt;
5369 ups[i].ups_cache_free += cache->uc_crossbucket.ucb_cnt;
5370 ups[i].ups_allocs = cache->uc_allocs;
5371 ups[i].ups_frees = cache->uc_frees;
5376 sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS)
5378 struct uma_stream_header ush;
5379 struct uma_type_header uth;
5380 struct uma_percpu_stat *ups;
5385 uint32_t kfree, pages;
5386 int count, error, i;
5388 error = sysctl_wire_old_buffer(req, 0);
5391 sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
5392 sbuf_clear_flags(&sbuf, SBUF_INCLUDENUL);
5393 ups = malloc((mp_maxid + 1) * sizeof(*ups), M_TEMP, M_WAITOK);
5396 rw_rlock(&uma_rwlock);
5397 LIST_FOREACH(kz, &uma_kegs, uk_link) {
5398 LIST_FOREACH(z, &kz->uk_zones, uz_link)
5402 LIST_FOREACH(z, &uma_cachezones, uz_link)
5406 * Insert stream header.
5408 bzero(&ush, sizeof(ush));
5409 ush.ush_version = UMA_STREAM_VERSION;
5410 ush.ush_maxcpus = (mp_maxid + 1);
5411 ush.ush_count = count;
5412 (void)sbuf_bcat(&sbuf, &ush, sizeof(ush));
5414 LIST_FOREACH(kz, &uma_kegs, uk_link) {
5416 for (i = 0; i < vm_ndomains; i++) {
5417 kfree += kz->uk_domain[i].ud_free_items;
5418 pages += kz->uk_domain[i].ud_pages;
5420 LIST_FOREACH(z, &kz->uk_zones, uz_link) {
5421 bzero(&uth, sizeof(uth));
5422 strlcpy(uth.uth_name, z->uz_name, UTH_MAX_NAME);
5423 uth.uth_align = kz->uk_align;
5424 uth.uth_size = kz->uk_size;
5425 uth.uth_rsize = kz->uk_rsize;
5426 if (z->uz_max_items > 0) {
5427 items = UZ_ITEMS_COUNT(z->uz_items);
5428 uth.uth_pages = (items / kz->uk_ipers) *
5431 uth.uth_pages = pages;
5432 uth.uth_maxpages = (z->uz_max_items / kz->uk_ipers) *
5434 uth.uth_limit = z->uz_max_items;
5435 uth.uth_keg_free = kfree;
5438 * A zone is secondary is it is not the first entry
5439 * on the keg's zone list.
5441 if ((z->uz_flags & UMA_ZONE_SECONDARY) &&
5442 (LIST_FIRST(&kz->uk_zones) != z))
5443 uth.uth_zone_flags = UTH_ZONE_SECONDARY;
5444 uma_vm_zone_stats(&uth, z, &sbuf, ups,
5445 kz->uk_flags & UMA_ZFLAG_INTERNAL);
5446 (void)sbuf_bcat(&sbuf, &uth, sizeof(uth));
5447 for (i = 0; i < mp_maxid + 1; i++)
5448 (void)sbuf_bcat(&sbuf, &ups[i], sizeof(ups[i]));
5451 LIST_FOREACH(z, &uma_cachezones, uz_link) {
5452 bzero(&uth, sizeof(uth));
5453 strlcpy(uth.uth_name, z->uz_name, UTH_MAX_NAME);
5454 uth.uth_size = z->uz_size;
5455 uma_vm_zone_stats(&uth, z, &sbuf, ups, false);
5456 (void)sbuf_bcat(&sbuf, &uth, sizeof(uth));
5457 for (i = 0; i < mp_maxid + 1; i++)
5458 (void)sbuf_bcat(&sbuf, &ups[i], sizeof(ups[i]));
5461 rw_runlock(&uma_rwlock);
5462 error = sbuf_finish(&sbuf);
5469 sysctl_handle_uma_zone_max(SYSCTL_HANDLER_ARGS)
5471 uma_zone_t zone = *(uma_zone_t *)arg1;
5474 max = uma_zone_get_max(zone);
5475 error = sysctl_handle_int(oidp, &max, 0, req);
5476 if (error || !req->newptr)
5479 uma_zone_set_max(zone, max);
5485 sysctl_handle_uma_zone_cur(SYSCTL_HANDLER_ARGS)
5491 * Some callers want to add sysctls for global zones that
5492 * may not yet exist so they pass a pointer to a pointer.
5495 zone = *(uma_zone_t *)arg1;
5498 cur = uma_zone_get_cur(zone);
5499 return (sysctl_handle_int(oidp, &cur, 0, req));
5503 sysctl_handle_uma_zone_allocs(SYSCTL_HANDLER_ARGS)
5505 uma_zone_t zone = arg1;
5508 cur = uma_zone_get_allocs(zone);
5509 return (sysctl_handle_64(oidp, &cur, 0, req));
5513 sysctl_handle_uma_zone_frees(SYSCTL_HANDLER_ARGS)
5515 uma_zone_t zone = arg1;
5518 cur = uma_zone_get_frees(zone);
5519 return (sysctl_handle_64(oidp, &cur, 0, req));
5523 sysctl_handle_uma_zone_flags(SYSCTL_HANDLER_ARGS)
5526 uma_zone_t zone = arg1;
5529 sbuf_new_for_sysctl(&sbuf, NULL, 0, req);
5530 if (zone->uz_flags != 0)
5531 sbuf_printf(&sbuf, "0x%b", zone->uz_flags, PRINT_UMA_ZFLAGS);
5533 sbuf_printf(&sbuf, "0");
5534 error = sbuf_finish(&sbuf);
5541 sysctl_handle_uma_slab_efficiency(SYSCTL_HANDLER_ARGS)
5543 uma_keg_t keg = arg1;
5544 int avail, effpct, total;
5546 total = keg->uk_ppera * PAGE_SIZE;
5547 if ((keg->uk_flags & UMA_ZFLAG_OFFPAGE) != 0)
5548 total += slabzone(keg->uk_ipers)->uz_keg->uk_rsize;
5550 * We consider the client's requested size and alignment here, not the
5551 * real size determination uk_rsize, because we also adjust the real
5552 * size for internal implementation reasons (max bitset size).
5554 avail = keg->uk_ipers * roundup2(keg->uk_size, keg->uk_align + 1);
5555 if ((keg->uk_flags & UMA_ZONE_PCPU) != 0)
5556 avail *= mp_maxid + 1;
5557 effpct = 100 * avail / total;
5558 return (sysctl_handle_int(oidp, &effpct, 0, req));
5562 sysctl_handle_uma_zone_items(SYSCTL_HANDLER_ARGS)
5564 uma_zone_t zone = arg1;
5567 cur = UZ_ITEMS_COUNT(atomic_load_64(&zone->uz_items));
5568 return (sysctl_handle_64(oidp, &cur, 0, req));
5573 uma_dbg_getslab(uma_zone_t zone, void *item)
5580 * It is safe to return the slab here even though the
5581 * zone is unlocked because the item's allocation state
5582 * essentially holds a reference.
5584 mem = (uint8_t *)((uintptr_t)item & (~UMA_SLAB_MASK));
5585 if ((zone->uz_flags & UMA_ZFLAG_CACHE) != 0)
5587 if (zone->uz_flags & UMA_ZFLAG_VTOSLAB)
5588 return (vtoslab((vm_offset_t)mem));
5590 if ((keg->uk_flags & UMA_ZFLAG_HASH) == 0)
5591 return ((uma_slab_t)(mem + keg->uk_pgoff));
5593 slab = hash_sfind(&keg->uk_hash, mem);
5600 uma_dbg_zskip(uma_zone_t zone, void *mem)
5603 if ((zone->uz_flags & UMA_ZFLAG_CACHE) != 0)
5606 return (uma_dbg_kskip(zone->uz_keg, mem));
5610 uma_dbg_kskip(uma_keg_t keg, void *mem)
5614 if (dbg_divisor == 0)
5617 if (dbg_divisor == 1)
5620 idx = (uintptr_t)mem >> PAGE_SHIFT;
5621 if (keg->uk_ipers > 1) {
5622 idx *= keg->uk_ipers;
5623 idx += ((uintptr_t)mem & PAGE_MASK) / keg->uk_rsize;
5626 if ((idx / dbg_divisor) * dbg_divisor != idx) {
5627 counter_u64_add(uma_skip_cnt, 1);
5630 counter_u64_add(uma_dbg_cnt, 1);
5636 * Set up the slab's freei data such that uma_dbg_free can function.
5640 uma_dbg_alloc(uma_zone_t zone, uma_slab_t slab, void *item)
5646 slab = uma_dbg_getslab(zone, item);
5648 panic("uma: item %p did not belong to zone %s",
5649 item, zone->uz_name);
5652 freei = slab_item_index(slab, keg, item);
5654 if (BIT_TEST_SET_ATOMIC(keg->uk_ipers, freei,
5655 slab_dbg_bits(slab, keg)))
5656 panic("Duplicate alloc of %p from zone %p(%s) slab %p(%d)",
5657 item, zone, zone->uz_name, slab, freei);
5661 * Verifies freed addresses. Checks for alignment, valid slab membership
5662 * and duplicate frees.
5666 uma_dbg_free(uma_zone_t zone, uma_slab_t slab, void *item)
5672 slab = uma_dbg_getslab(zone, item);
5674 panic("uma: Freed item %p did not belong to zone %s",
5675 item, zone->uz_name);
5678 freei = slab_item_index(slab, keg, item);
5680 if (freei >= keg->uk_ipers)
5681 panic("Invalid free of %p from zone %p(%s) slab %p(%d)",
5682 item, zone, zone->uz_name, slab, freei);
5684 if (slab_item(slab, keg, freei) != item)
5685 panic("Unaligned free of %p from zone %p(%s) slab %p(%d)",
5686 item, zone, zone->uz_name, slab, freei);
5688 if (!BIT_TEST_CLR_ATOMIC(keg->uk_ipers, freei,
5689 slab_dbg_bits(slab, keg)))
5690 panic("Duplicate free of %p from zone %p(%s) slab %p(%d)",
5691 item, zone, zone->uz_name, slab, freei);
5693 #endif /* INVARIANTS */
5697 get_uma_stats(uma_keg_t kz, uma_zone_t z, uint64_t *allocs, uint64_t *used,
5698 uint64_t *sleeps, long *cachefree, uint64_t *xdomain)
5703 if (kz->uk_flags & UMA_ZFLAG_INTERNAL) {
5704 *allocs = counter_u64_fetch(z->uz_allocs);
5705 frees = counter_u64_fetch(z->uz_frees);
5706 *sleeps = z->uz_sleeps;
5710 uma_zone_sumstat(z, cachefree, allocs, &frees, sleeps,
5712 for (i = 0; i < vm_ndomains; i++) {
5713 *cachefree += ZDOM_GET(z, i)->uzd_nitems;
5714 if (!((z->uz_flags & UMA_ZONE_SECONDARY) &&
5715 (LIST_FIRST(&kz->uk_zones) != z)))
5716 *cachefree += kz->uk_domain[i].ud_free_items;
5718 *used = *allocs - frees;
5719 return (((int64_t)*used + *cachefree) * kz->uk_size);
5722 DB_SHOW_COMMAND(uma, db_show_uma)
5724 const char *fmt_hdr, *fmt_entry;
5727 uint64_t allocs, used, sleeps, xdomain;
5729 /* variables for sorting */
5731 uma_zone_t cur_zone, last_zone;
5732 int64_t cur_size, last_size, size;
5735 /* /i option produces machine-parseable CSV output */
5736 if (modif[0] == 'i') {
5737 fmt_hdr = "%s,%s,%s,%s,%s,%s,%s,%s,%s\n";
5738 fmt_entry = "\"%s\",%ju,%jd,%ld,%ju,%ju,%u,%jd,%ju\n";
5740 fmt_hdr = "%18s %6s %7s %7s %11s %7s %7s %10s %8s\n";
5741 fmt_entry = "%18s %6ju %7jd %7ld %11ju %7ju %7u %10jd %8ju\n";
5744 db_printf(fmt_hdr, "Zone", "Size", "Used", "Free", "Requests",
5745 "Sleeps", "Bucket", "Total Mem", "XFree");
5747 /* Sort the zones with largest size first. */
5749 last_size = INT64_MAX;
5754 LIST_FOREACH(kz, &uma_kegs, uk_link) {
5755 LIST_FOREACH(z, &kz->uk_zones, uz_link) {
5757 * In the case of size ties, print out zones
5758 * in the order they are encountered. That is,
5759 * when we encounter the most recently output
5760 * zone, we have already printed all preceding
5761 * ties, and we must print all following ties.
5763 if (z == last_zone) {
5767 size = get_uma_stats(kz, z, &allocs, &used,
5768 &sleeps, &cachefree, &xdomain);
5769 if (size > cur_size && size < last_size + ties)
5777 if (cur_zone == NULL)
5780 size = get_uma_stats(cur_keg, cur_zone, &allocs, &used,
5781 &sleeps, &cachefree, &xdomain);
5782 db_printf(fmt_entry, cur_zone->uz_name,
5783 (uintmax_t)cur_keg->uk_size, (intmax_t)used, cachefree,
5784 (uintmax_t)allocs, (uintmax_t)sleeps,
5785 (unsigned)cur_zone->uz_bucket_size, (intmax_t)size,
5790 last_zone = cur_zone;
5791 last_size = cur_size;
5795 DB_SHOW_COMMAND(umacache, db_show_umacache)
5798 uint64_t allocs, frees;
5802 db_printf("%18s %8s %8s %8s %12s %8s\n", "Zone", "Size", "Used", "Free",
5803 "Requests", "Bucket");
5804 LIST_FOREACH(z, &uma_cachezones, uz_link) {
5805 uma_zone_sumstat(z, &cachefree, &allocs, &frees, NULL, NULL);
5806 for (i = 0; i < vm_ndomains; i++)
5807 cachefree += ZDOM_GET(z, i)->uzd_nitems;
5808 db_printf("%18s %8ju %8jd %8ld %12ju %8u\n",
5809 z->uz_name, (uintmax_t)z->uz_size,
5810 (intmax_t)(allocs - frees), cachefree,
5811 (uintmax_t)allocs, z->uz_bucket_size);