2 * Copyright (c) 2002-2005, 2009, 2013 Jeffrey Roberson <jeff@FreeBSD.org>
3 * Copyright (c) 2004, 2005 Bosko Milekic <bmilekic@FreeBSD.org>
4 * Copyright (c) 2004-2006 Robert N. M. Watson
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice unmodified, this list of conditions, and the following
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 * uma_core.c Implementation of the Universal Memory allocator
32 * This allocator is intended to replace the multitude of similar object caches
33 * in the standard FreeBSD kernel. The intent is to be flexible as well as
34 * effecient. A primary design goal is to return unused memory to the rest of
35 * the system. This will make the system as a whole more flexible due to the
36 * ability to move memory to subsystems which most need it instead of leaving
37 * pools of reserved memory unused.
39 * The basic ideas stem from similar slab/zone based allocators whose algorithms
46 * - Improve memory usage for large allocations
47 * - Investigate cache size adjustments
50 #include <sys/cdefs.h>
51 __FBSDID("$FreeBSD$");
53 /* I should really use ktr.. */
56 #define UMA_DEBUG_ALLOC 1
57 #define UMA_DEBUG_ALLOC_1 1
61 #include "opt_param.h"
64 #include <sys/param.h>
65 #include <sys/systm.h>
66 #include <sys/bitset.h>
67 #include <sys/kernel.h>
68 #include <sys/types.h>
69 #include <sys/queue.h>
70 #include <sys/malloc.h>
73 #include <sys/sysctl.h>
74 #include <sys/mutex.h>
76 #include <sys/rwlock.h>
78 #include <sys/sched.h>
80 #include <sys/vmmeter.h>
83 #include <vm/vm_object.h>
84 #include <vm/vm_page.h>
85 #include <vm/vm_pageout.h>
86 #include <vm/vm_param.h>
87 #include <vm/vm_map.h>
88 #include <vm/vm_kern.h>
89 #include <vm/vm_extern.h>
91 #include <vm/uma_int.h>
92 #include <vm/uma_dbg.h>
97 #include <vm/memguard.h>
101 * This is the zone and keg from which all zones are spawned. The idea is that
102 * even the zone & keg heads are allocated from the allocator, so we use the
103 * bss section to bootstrap us.
105 static struct uma_keg masterkeg;
106 static struct uma_zone masterzone_k;
107 static struct uma_zone masterzone_z;
108 static uma_zone_t kegs = &masterzone_k;
109 static uma_zone_t zones = &masterzone_z;
111 /* This is the zone from which all of uma_slab_t's are allocated. */
112 static uma_zone_t slabzone;
113 static uma_zone_t slabrefzone; /* With refcounters (for UMA_ZONE_REFCNT) */
116 * The initial hash tables come out of this zone so they can be allocated
117 * prior to malloc coming up.
119 static uma_zone_t hashzone;
121 /* The boot-time adjusted value for cache line alignment. */
122 int uma_align_cache = 64 - 1;
124 static MALLOC_DEFINE(M_UMAHASH, "UMAHash", "UMA Hash Buckets");
127 * Are we allowed to allocate buckets?
129 static int bucketdisable = 1;
131 /* Linked list of all kegs in the system */
132 static LIST_HEAD(,uma_keg) uma_kegs = LIST_HEAD_INITIALIZER(uma_kegs);
134 /* Linked list of all cache-only zones in the system */
135 static LIST_HEAD(,uma_zone) uma_cachezones =
136 LIST_HEAD_INITIALIZER(uma_cachezones);
138 /* This mutex protects the keg list */
139 static struct mtx_padalign uma_mtx;
141 /* Linked list of boot time pages */
142 static LIST_HEAD(,uma_slab) uma_boot_pages =
143 LIST_HEAD_INITIALIZER(uma_boot_pages);
145 /* This mutex protects the boot time pages list */
146 static struct mtx_padalign uma_boot_pages_mtx;
148 /* Is the VM done starting up? */
149 static int booted = 0;
150 #define UMA_STARTUP 1
151 #define UMA_STARTUP2 2
154 * Only mbuf clusters use ref zones. Just provide enough references
155 * to support the one user. New code should not use the ref facility.
157 static const u_int uma_max_ipers_ref = PAGE_SIZE / MCLBYTES;
160 * This is the handle used to schedule events that need to happen
161 * outside of the allocation fast path.
163 static struct callout uma_callout;
164 #define UMA_TIMEOUT 20 /* Seconds for callout interval. */
167 * This structure is passed as the zone ctor arg so that I don't have to create
168 * a special allocation function just for zones.
170 struct uma_zctor_args {
185 struct uma_kctor_args {
194 struct uma_bucket_zone {
197 int ubz_entries; /* Number of items it can hold. */
198 int ubz_maxsize; /* Maximum allocation size per-item. */
202 * Compute the actual number of bucket entries to pack them in power
203 * of two sizes for more efficient space utilization.
205 #define BUCKET_SIZE(n) \
206 (((sizeof(void *) * (n)) - sizeof(struct uma_bucket)) / sizeof(void *))
208 #define BUCKET_MAX BUCKET_SIZE(256)
210 struct uma_bucket_zone bucket_zones[] = {
211 { NULL, "4 Bucket", BUCKET_SIZE(4), 4096 },
212 { NULL, "6 Bucket", BUCKET_SIZE(6), 3072 },
213 { NULL, "8 Bucket", BUCKET_SIZE(8), 2048 },
214 { NULL, "12 Bucket", BUCKET_SIZE(12), 1536 },
215 { NULL, "16 Bucket", BUCKET_SIZE(16), 1024 },
216 { NULL, "32 Bucket", BUCKET_SIZE(32), 512 },
217 { NULL, "64 Bucket", BUCKET_SIZE(64), 256 },
218 { NULL, "128 Bucket", BUCKET_SIZE(128), 128 },
219 { NULL, "256 Bucket", BUCKET_SIZE(256), 64 },
224 * Flags and enumerations to be passed to internal functions.
226 enum zfreeskip { SKIP_NONE = 0, SKIP_DTOR, SKIP_FINI };
230 static void *noobj_alloc(uma_zone_t, int, uint8_t *, int);
231 static void *page_alloc(uma_zone_t, int, uint8_t *, int);
232 static void *startup_alloc(uma_zone_t, int, uint8_t *, int);
233 static void page_free(void *, int, uint8_t);
234 static uma_slab_t keg_alloc_slab(uma_keg_t, uma_zone_t, int);
235 static void cache_drain(uma_zone_t);
236 static void bucket_drain(uma_zone_t, uma_bucket_t);
237 static void bucket_cache_drain(uma_zone_t zone);
238 static int keg_ctor(void *, int, void *, int);
239 static void keg_dtor(void *, int, void *);
240 static int zone_ctor(void *, int, void *, int);
241 static void zone_dtor(void *, int, void *);
242 static int zero_init(void *, int, int);
243 static void keg_small_init(uma_keg_t keg);
244 static void keg_large_init(uma_keg_t keg);
245 static void zone_foreach(void (*zfunc)(uma_zone_t));
246 static void zone_timeout(uma_zone_t zone);
247 static int hash_alloc(struct uma_hash *);
248 static int hash_expand(struct uma_hash *, struct uma_hash *);
249 static void hash_free(struct uma_hash *hash);
250 static void uma_timeout(void *);
251 static void uma_startup3(void);
252 static void *zone_alloc_item(uma_zone_t, void *, int);
253 static void zone_free_item(uma_zone_t, void *, void *, enum zfreeskip);
254 static void bucket_enable(void);
255 static void bucket_init(void);
256 static uma_bucket_t bucket_alloc(uma_zone_t zone, void *, int);
257 static void bucket_free(uma_zone_t zone, uma_bucket_t, void *);
258 static void bucket_zone_drain(void);
259 static uma_bucket_t zone_alloc_bucket(uma_zone_t zone, void *, int flags);
260 static uma_slab_t zone_fetch_slab(uma_zone_t zone, uma_keg_t last, int flags);
261 static uma_slab_t zone_fetch_slab_multi(uma_zone_t zone, uma_keg_t last, int flags);
262 static void *slab_alloc_item(uma_keg_t keg, uma_slab_t slab);
263 static void slab_free_item(uma_keg_t keg, uma_slab_t slab, void *item);
264 static uma_keg_t uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit,
265 uma_fini fini, int align, uint32_t flags);
266 static int zone_import(uma_zone_t zone, void **bucket, int max, int flags);
267 static void zone_release(uma_zone_t zone, void **bucket, int cnt);
268 static void uma_zero_item(void *item, uma_zone_t zone);
270 void uma_print_zone(uma_zone_t);
271 void uma_print_stats(void);
272 static int sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS);
273 static int sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS);
275 SYSINIT(uma_startup3, SI_SUB_VM_CONF, SI_ORDER_SECOND, uma_startup3, NULL);
277 SYSCTL_PROC(_vm, OID_AUTO, zone_count, CTLFLAG_RD|CTLTYPE_INT,
278 0, 0, sysctl_vm_zone_count, "I", "Number of UMA zones");
280 SYSCTL_PROC(_vm, OID_AUTO, zone_stats, CTLFLAG_RD|CTLTYPE_STRUCT,
281 0, 0, sysctl_vm_zone_stats, "s,struct uma_type_header", "Zone Stats");
283 static int zone_warnings = 1;
284 SYSCTL_INT(_vm, OID_AUTO, zone_warnings, CTLFLAG_RWTUN, &zone_warnings, 0,
285 "Warn when UMA zones becomes full");
288 * This routine checks to see whether or not it's safe to enable buckets.
293 bucketdisable = vm_page_count_min();
297 * Initialize bucket_zones, the array of zones of buckets of various sizes.
299 * For each zone, calculate the memory required for each bucket, consisting
300 * of the header and an array of pointers.
305 struct uma_bucket_zone *ubz;
309 for (i = 0, ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++) {
310 size = roundup(sizeof(struct uma_bucket), sizeof(void *));
311 size += sizeof(void *) * ubz->ubz_entries;
312 ubz->ubz_zone = uma_zcreate(ubz->ubz_name, size,
313 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR,
314 UMA_ZONE_MTXCLASS | UMA_ZFLAG_BUCKET);
319 * Given a desired number of entries for a bucket, return the zone from which
320 * to allocate the bucket.
322 static struct uma_bucket_zone *
323 bucket_zone_lookup(int entries)
325 struct uma_bucket_zone *ubz;
327 for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++)
328 if (ubz->ubz_entries >= entries)
335 bucket_select(int size)
337 struct uma_bucket_zone *ubz;
339 ubz = &bucket_zones[0];
340 if (size > ubz->ubz_maxsize)
341 return MAX((ubz->ubz_maxsize * ubz->ubz_entries) / size, 1);
343 for (; ubz->ubz_entries != 0; ubz++)
344 if (ubz->ubz_maxsize < size)
347 return (ubz->ubz_entries);
351 bucket_alloc(uma_zone_t zone, void *udata, int flags)
353 struct uma_bucket_zone *ubz;
357 * This is to stop us from allocating per cpu buckets while we're
358 * running out of vm.boot_pages. Otherwise, we would exhaust the
359 * boot pages. This also prevents us from allocating buckets in
360 * low memory situations.
365 * To limit bucket recursion we store the original zone flags
366 * in a cookie passed via zalloc_arg/zfree_arg. This allows the
367 * NOVM flag to persist even through deep recursions. We also
368 * store ZFLAG_BUCKET once we have recursed attempting to allocate
369 * a bucket for a bucket zone so we do not allow infinite bucket
370 * recursion. This cookie will even persist to frees of unused
371 * buckets via the allocation path or bucket allocations in the
374 if ((zone->uz_flags & UMA_ZFLAG_BUCKET) == 0)
375 udata = (void *)(uintptr_t)zone->uz_flags;
377 if ((uintptr_t)udata & UMA_ZFLAG_BUCKET)
379 udata = (void *)((uintptr_t)udata | UMA_ZFLAG_BUCKET);
381 if ((uintptr_t)udata & UMA_ZFLAG_CACHEONLY)
383 ubz = bucket_zone_lookup(zone->uz_count);
384 if (ubz->ubz_zone == zone && (ubz + 1)->ubz_entries != 0)
386 bucket = uma_zalloc_arg(ubz->ubz_zone, udata, flags);
389 bzero(bucket->ub_bucket, sizeof(void *) * ubz->ubz_entries);
392 bucket->ub_entries = ubz->ubz_entries;
399 bucket_free(uma_zone_t zone, uma_bucket_t bucket, void *udata)
401 struct uma_bucket_zone *ubz;
403 KASSERT(bucket->ub_cnt == 0,
404 ("bucket_free: Freeing a non free bucket."));
405 if ((zone->uz_flags & UMA_ZFLAG_BUCKET) == 0)
406 udata = (void *)(uintptr_t)zone->uz_flags;
407 ubz = bucket_zone_lookup(bucket->ub_entries);
408 uma_zfree_arg(ubz->ubz_zone, bucket, udata);
412 bucket_zone_drain(void)
414 struct uma_bucket_zone *ubz;
416 for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++)
417 zone_drain(ubz->ubz_zone);
421 zone_log_warning(uma_zone_t zone)
423 static const struct timeval warninterval = { 300, 0 };
425 if (!zone_warnings || zone->uz_warning == NULL)
428 if (ratecheck(&zone->uz_ratecheck, &warninterval))
429 printf("[zone: %s] %s\n", zone->uz_name, zone->uz_warning);
433 zone_foreach_keg(uma_zone_t zone, void (*kegfn)(uma_keg_t))
437 LIST_FOREACH(klink, &zone->uz_kegs, kl_link)
438 kegfn(klink->kl_keg);
442 * Routine called by timeout which is used to fire off some time interval
443 * based calculations. (stats, hash size, etc.)
452 uma_timeout(void *unused)
455 zone_foreach(zone_timeout);
457 /* Reschedule this event */
458 callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL);
462 * Routine to perform timeout driven calculations. This expands the
463 * hashes and does per cpu statistics aggregation.
468 keg_timeout(uma_keg_t keg)
473 * Expand the keg hash table.
475 * This is done if the number of slabs is larger than the hash size.
476 * What I'm trying to do here is completely reduce collisions. This
477 * may be a little aggressive. Should I allow for two collisions max?
479 if (keg->uk_flags & UMA_ZONE_HASH &&
480 keg->uk_pages / keg->uk_ppera >= keg->uk_hash.uh_hashsize) {
481 struct uma_hash newhash;
482 struct uma_hash oldhash;
486 * This is so involved because allocating and freeing
487 * while the keg lock is held will lead to deadlock.
488 * I have to do everything in stages and check for
491 newhash = keg->uk_hash;
493 ret = hash_alloc(&newhash);
496 if (hash_expand(&keg->uk_hash, &newhash)) {
497 oldhash = keg->uk_hash;
498 keg->uk_hash = newhash;
511 zone_timeout(uma_zone_t zone)
514 zone_foreach_keg(zone, &keg_timeout);
518 * Allocate and zero fill the next sized hash table from the appropriate
522 * hash A new hash structure with the old hash size in uh_hashsize
525 * 1 on sucess and 0 on failure.
528 hash_alloc(struct uma_hash *hash)
533 oldsize = hash->uh_hashsize;
535 /* We're just going to go to a power of two greater */
537 hash->uh_hashsize = oldsize * 2;
538 alloc = sizeof(hash->uh_slab_hash[0]) * hash->uh_hashsize;
539 hash->uh_slab_hash = (struct slabhead *)malloc(alloc,
540 M_UMAHASH, M_NOWAIT);
542 alloc = sizeof(hash->uh_slab_hash[0]) * UMA_HASH_SIZE_INIT;
543 hash->uh_slab_hash = zone_alloc_item(hashzone, NULL,
545 hash->uh_hashsize = UMA_HASH_SIZE_INIT;
547 if (hash->uh_slab_hash) {
548 bzero(hash->uh_slab_hash, alloc);
549 hash->uh_hashmask = hash->uh_hashsize - 1;
557 * Expands the hash table for HASH zones. This is done from zone_timeout
558 * to reduce collisions. This must not be done in the regular allocation
559 * path, otherwise, we can recurse on the vm while allocating pages.
562 * oldhash The hash you want to expand
563 * newhash The hash structure for the new table
571 hash_expand(struct uma_hash *oldhash, struct uma_hash *newhash)
577 if (!newhash->uh_slab_hash)
580 if (oldhash->uh_hashsize >= newhash->uh_hashsize)
584 * I need to investigate hash algorithms for resizing without a
588 for (i = 0; i < oldhash->uh_hashsize; i++)
589 while (!SLIST_EMPTY(&oldhash->uh_slab_hash[i])) {
590 slab = SLIST_FIRST(&oldhash->uh_slab_hash[i]);
591 SLIST_REMOVE_HEAD(&oldhash->uh_slab_hash[i], us_hlink);
592 hval = UMA_HASH(newhash, slab->us_data);
593 SLIST_INSERT_HEAD(&newhash->uh_slab_hash[hval],
601 * Free the hash bucket to the appropriate backing store.
604 * slab_hash The hash bucket we're freeing
605 * hashsize The number of entries in that hash bucket
611 hash_free(struct uma_hash *hash)
613 if (hash->uh_slab_hash == NULL)
615 if (hash->uh_hashsize == UMA_HASH_SIZE_INIT)
616 zone_free_item(hashzone, hash->uh_slab_hash, NULL, SKIP_NONE);
618 free(hash->uh_slab_hash, M_UMAHASH);
622 * Frees all outstanding items in a bucket
625 * zone The zone to free to, must be unlocked.
626 * bucket The free/alloc bucket with items, cpu queue must be locked.
633 bucket_drain(uma_zone_t zone, uma_bucket_t bucket)
641 for (i = 0; i < bucket->ub_cnt; i++)
642 zone->uz_fini(bucket->ub_bucket[i], zone->uz_size);
643 zone->uz_release(zone->uz_arg, bucket->ub_bucket, bucket->ub_cnt);
648 * Drains the per cpu caches for a zone.
650 * NOTE: This may only be called while the zone is being turn down, and not
651 * during normal operation. This is necessary in order that we do not have
652 * to migrate CPUs to drain the per-CPU caches.
655 * zone The zone to drain, must be unlocked.
661 cache_drain(uma_zone_t zone)
667 * XXX: It is safe to not lock the per-CPU caches, because we're
668 * tearing down the zone anyway. I.e., there will be no further use
669 * of the caches at this point.
671 * XXX: It would good to be able to assert that the zone is being
672 * torn down to prevent improper use of cache_drain().
674 * XXX: We lock the zone before passing into bucket_cache_drain() as
675 * it is used elsewhere. Should the tear-down path be made special
676 * there in some form?
679 cache = &zone->uz_cpu[cpu];
680 bucket_drain(zone, cache->uc_allocbucket);
681 bucket_drain(zone, cache->uc_freebucket);
682 if (cache->uc_allocbucket != NULL)
683 bucket_free(zone, cache->uc_allocbucket, NULL);
684 if (cache->uc_freebucket != NULL)
685 bucket_free(zone, cache->uc_freebucket, NULL);
686 cache->uc_allocbucket = cache->uc_freebucket = NULL;
689 bucket_cache_drain(zone);
694 cache_shrink(uma_zone_t zone)
697 if (zone->uz_flags & UMA_ZFLAG_INTERNAL)
701 zone->uz_count = (zone->uz_count_min + zone->uz_count) / 2;
706 cache_drain_safe_cpu(uma_zone_t zone)
711 if (zone->uz_flags & UMA_ZFLAG_INTERNAL)
717 cache = &zone->uz_cpu[curcpu];
718 if (cache->uc_allocbucket) {
719 if (cache->uc_allocbucket->ub_cnt != 0)
720 LIST_INSERT_HEAD(&zone->uz_buckets,
721 cache->uc_allocbucket, ub_link);
723 b1 = cache->uc_allocbucket;
724 cache->uc_allocbucket = NULL;
726 if (cache->uc_freebucket) {
727 if (cache->uc_freebucket->ub_cnt != 0)
728 LIST_INSERT_HEAD(&zone->uz_buckets,
729 cache->uc_freebucket, ub_link);
731 b2 = cache->uc_freebucket;
732 cache->uc_freebucket = NULL;
737 bucket_free(zone, b1, NULL);
739 bucket_free(zone, b2, NULL);
743 * Safely drain per-CPU caches of a zone(s) to alloc bucket.
744 * This is an expensive call because it needs to bind to all CPUs
745 * one by one and enter a critical section on each of them in order
746 * to safely access their cache buckets.
747 * Zone lock must not be held on call this function.
750 cache_drain_safe(uma_zone_t zone)
755 * Polite bucket sizes shrinking was not enouth, shrink aggressively.
760 zone_foreach(cache_shrink);
763 thread_lock(curthread);
764 sched_bind(curthread, cpu);
765 thread_unlock(curthread);
768 cache_drain_safe_cpu(zone);
770 zone_foreach(cache_drain_safe_cpu);
772 thread_lock(curthread);
773 sched_unbind(curthread);
774 thread_unlock(curthread);
778 * Drain the cached buckets from a zone. Expects a locked zone on entry.
781 bucket_cache_drain(uma_zone_t zone)
786 * Drain the bucket queues and free the buckets, we just keep two per
789 while ((bucket = LIST_FIRST(&zone->uz_buckets)) != NULL) {
790 LIST_REMOVE(bucket, ub_link);
792 bucket_drain(zone, bucket);
793 bucket_free(zone, bucket, NULL);
798 * Shrink further bucket sizes. Price of single zone lock collision
799 * is probably lower then price of global cache drain.
801 if (zone->uz_count > zone->uz_count_min)
806 keg_free_slab(uma_keg_t keg, uma_slab_t slab, int start)
813 flags = slab->us_flags;
815 if (keg->uk_fini != NULL) {
816 for (i--; i > -1; i--)
817 keg->uk_fini(slab->us_data + (keg->uk_rsize * i),
820 if (keg->uk_flags & UMA_ZONE_OFFPAGE)
821 zone_free_item(keg->uk_slabzone, slab, NULL, SKIP_NONE);
823 printf("%s: Returning %d bytes.\n", keg->uk_name,
824 PAGE_SIZE * keg->uk_ppera);
826 keg->uk_freef(mem, PAGE_SIZE * keg->uk_ppera, flags);
830 * Frees pages from a keg back to the system. This is done on demand from
831 * the pageout daemon.
836 keg_drain(uma_keg_t keg)
838 struct slabhead freeslabs = { 0 };
843 * We don't want to take pages from statically allocated kegs at this
846 if (keg->uk_flags & UMA_ZONE_NOFREE || keg->uk_freef == NULL)
850 printf("%s free items: %u\n", keg->uk_name, keg->uk_free);
853 if (keg->uk_free == 0)
856 slab = LIST_FIRST(&keg->uk_free_slab);
858 n = LIST_NEXT(slab, us_link);
860 /* We have no where to free these to */
861 if (slab->us_flags & UMA_SLAB_BOOT) {
866 LIST_REMOVE(slab, us_link);
867 keg->uk_pages -= keg->uk_ppera;
868 keg->uk_free -= keg->uk_ipers;
870 if (keg->uk_flags & UMA_ZONE_HASH)
871 UMA_HASH_REMOVE(&keg->uk_hash, slab, slab->us_data);
873 SLIST_INSERT_HEAD(&freeslabs, slab, us_hlink);
880 while ((slab = SLIST_FIRST(&freeslabs)) != NULL) {
881 SLIST_REMOVE(&freeslabs, slab, uma_slab, us_hlink);
882 keg_free_slab(keg, slab, keg->uk_ipers);
887 zone_drain_wait(uma_zone_t zone, int waitok)
891 * Set draining to interlock with zone_dtor() so we can release our
892 * locks as we go. Only dtor() should do a WAITOK call since it
893 * is the only call that knows the structure will still be available
897 while (zone->uz_flags & UMA_ZFLAG_DRAINING) {
898 if (waitok == M_NOWAIT)
900 mtx_unlock(&uma_mtx);
901 msleep(zone, zone->uz_lockptr, PVM, "zonedrain", 1);
904 zone->uz_flags |= UMA_ZFLAG_DRAINING;
905 bucket_cache_drain(zone);
908 * The DRAINING flag protects us from being freed while
909 * we're running. Normally the uma_mtx would protect us but we
910 * must be able to release and acquire the right lock for each keg.
912 zone_foreach_keg(zone, &keg_drain);
914 zone->uz_flags &= ~UMA_ZFLAG_DRAINING;
921 zone_drain(uma_zone_t zone)
924 zone_drain_wait(zone, M_NOWAIT);
928 * Allocate a new slab for a keg. This does not insert the slab onto a list.
931 * wait Shall we wait?
934 * The slab that was allocated or NULL if there is no memory and the
935 * caller specified M_NOWAIT.
938 keg_alloc_slab(uma_keg_t keg, uma_zone_t zone, int wait)
940 uma_slabrefcnt_t slabref;
947 mtx_assert(&keg->uk_lock, MA_OWNED);
952 printf("alloc_slab: Allocating a new slab for %s\n", keg->uk_name);
954 allocf = keg->uk_allocf;
957 if (keg->uk_flags & UMA_ZONE_OFFPAGE) {
958 slab = zone_alloc_item(keg->uk_slabzone, NULL, wait);
964 * This reproduces the old vm_zone behavior of zero filling pages the
965 * first time they are added to a zone.
967 * Malloced items are zeroed in uma_zalloc.
970 if ((keg->uk_flags & UMA_ZONE_MALLOC) == 0)
975 if (keg->uk_flags & UMA_ZONE_NODUMP)
978 /* zone is passed for legacy reasons. */
979 mem = allocf(zone, keg->uk_ppera * PAGE_SIZE, &flags, wait);
981 if (keg->uk_flags & UMA_ZONE_OFFPAGE)
982 zone_free_item(keg->uk_slabzone, slab, NULL, SKIP_NONE);
987 /* Point the slab into the allocated memory */
988 if (!(keg->uk_flags & UMA_ZONE_OFFPAGE))
989 slab = (uma_slab_t )(mem + keg->uk_pgoff);
991 if (keg->uk_flags & UMA_ZONE_VTOSLAB)
992 for (i = 0; i < keg->uk_ppera; i++)
993 vsetslab((vm_offset_t)mem + (i * PAGE_SIZE), slab);
997 slab->us_freecount = keg->uk_ipers;
998 slab->us_flags = flags;
999 BIT_FILL(SLAB_SETSIZE, &slab->us_free);
1001 BIT_ZERO(SLAB_SETSIZE, &slab->us_debugfree);
1003 if (keg->uk_flags & UMA_ZONE_REFCNT) {
1004 slabref = (uma_slabrefcnt_t)slab;
1005 for (i = 0; i < keg->uk_ipers; i++)
1006 slabref->us_refcnt[i] = 0;
1009 if (keg->uk_init != NULL) {
1010 for (i = 0; i < keg->uk_ipers; i++)
1011 if (keg->uk_init(slab->us_data + (keg->uk_rsize * i),
1012 keg->uk_size, wait) != 0)
1014 if (i != keg->uk_ipers) {
1015 keg_free_slab(keg, slab, i);
1024 if (keg->uk_flags & UMA_ZONE_HASH)
1025 UMA_HASH_INSERT(&keg->uk_hash, slab, mem);
1027 keg->uk_pages += keg->uk_ppera;
1028 keg->uk_free += keg->uk_ipers;
1035 * This function is intended to be used early on in place of page_alloc() so
1036 * that we may use the boot time page cache to satisfy allocations before
1040 startup_alloc(uma_zone_t zone, int bytes, uint8_t *pflag, int wait)
1044 int pages, check_pages;
1046 keg = zone_first_keg(zone);
1047 pages = howmany(bytes, PAGE_SIZE);
1048 check_pages = pages - 1;
1049 KASSERT(pages > 0, ("startup_alloc can't reserve 0 pages\n"));
1052 * Check our small startup cache to see if it has pages remaining.
1054 mtx_lock(&uma_boot_pages_mtx);
1056 /* First check if we have enough room. */
1057 tmps = LIST_FIRST(&uma_boot_pages);
1058 while (tmps != NULL && check_pages-- > 0)
1059 tmps = LIST_NEXT(tmps, us_link);
1062 * It's ok to lose tmps references. The last one will
1063 * have tmps->us_data pointing to the start address of
1064 * "pages" contiguous pages of memory.
1066 while (pages-- > 0) {
1067 tmps = LIST_FIRST(&uma_boot_pages);
1068 LIST_REMOVE(tmps, us_link);
1070 mtx_unlock(&uma_boot_pages_mtx);
1071 *pflag = tmps->us_flags;
1072 return (tmps->us_data);
1074 mtx_unlock(&uma_boot_pages_mtx);
1075 if (booted < UMA_STARTUP2)
1076 panic("UMA: Increase vm.boot_pages");
1078 * Now that we've booted reset these users to their real allocator.
1080 #ifdef UMA_MD_SMALL_ALLOC
1081 keg->uk_allocf = (keg->uk_ppera > 1) ? page_alloc : uma_small_alloc;
1083 keg->uk_allocf = page_alloc;
1085 return keg->uk_allocf(zone, bytes, pflag, wait);
1089 * Allocates a number of pages from the system
1092 * bytes The number of bytes requested
1093 * wait Shall we wait?
1096 * A pointer to the alloced memory or possibly
1097 * NULL if M_NOWAIT is set.
1100 page_alloc(uma_zone_t zone, int bytes, uint8_t *pflag, int wait)
1102 void *p; /* Returned page */
1104 *pflag = UMA_SLAB_KMEM;
1105 p = (void *) kmem_malloc(kmem_arena, bytes, wait);
1111 * Allocates a number of pages from within an object
1114 * bytes The number of bytes requested
1115 * wait Shall we wait?
1118 * A pointer to the alloced memory or possibly
1119 * NULL if M_NOWAIT is set.
1122 noobj_alloc(uma_zone_t zone, int bytes, uint8_t *flags, int wait)
1124 TAILQ_HEAD(, vm_page) alloctail;
1126 vm_offset_t retkva, zkva;
1127 vm_page_t p, p_next;
1130 TAILQ_INIT(&alloctail);
1131 keg = zone_first_keg(zone);
1133 npages = howmany(bytes, PAGE_SIZE);
1134 while (npages > 0) {
1135 p = vm_page_alloc(NULL, 0, VM_ALLOC_INTERRUPT |
1136 VM_ALLOC_WIRED | VM_ALLOC_NOOBJ);
1139 * Since the page does not belong to an object, its
1142 TAILQ_INSERT_TAIL(&alloctail, p, listq);
1146 if (wait & M_WAITOK) {
1152 * Page allocation failed, free intermediate pages and
1155 TAILQ_FOREACH_SAFE(p, &alloctail, listq, p_next) {
1156 vm_page_unwire(p, PQ_INACTIVE);
1161 *flags = UMA_SLAB_PRIV;
1162 zkva = keg->uk_kva +
1163 atomic_fetchadd_long(&keg->uk_offset, round_page(bytes));
1165 TAILQ_FOREACH(p, &alloctail, listq) {
1166 pmap_qenter(zkva, &p, 1);
1170 return ((void *)retkva);
1174 * Frees a number of pages to the system
1177 * mem A pointer to the memory to be freed
1178 * size The size of the memory being freed
1179 * flags The original p->us_flags field
1185 page_free(void *mem, int size, uint8_t flags)
1189 if (flags & UMA_SLAB_KMEM)
1191 else if (flags & UMA_SLAB_KERNEL)
1192 vmem = kernel_arena;
1194 panic("UMA: page_free used with invalid flags %d", flags);
1196 kmem_free(vmem, (vm_offset_t)mem, size);
1200 * Zero fill initializer
1202 * Arguments/Returns follow uma_init specifications
1205 zero_init(void *mem, int size, int flags)
1212 * Finish creating a small uma keg. This calculates ipers, and the keg size.
1215 * keg The zone we should initialize
1221 keg_small_init(uma_keg_t keg)
1228 if (keg->uk_flags & UMA_ZONE_PCPU) {
1229 u_int ncpus = mp_ncpus ? mp_ncpus : MAXCPU;
1231 keg->uk_slabsize = sizeof(struct pcpu);
1232 keg->uk_ppera = howmany(ncpus * sizeof(struct pcpu),
1235 keg->uk_slabsize = UMA_SLAB_SIZE;
1240 * Calculate the size of each allocation (rsize) according to
1241 * alignment. If the requested size is smaller than we have
1242 * allocation bits for we round it up.
1244 rsize = keg->uk_size;
1245 if (rsize < keg->uk_slabsize / SLAB_SETSIZE)
1246 rsize = keg->uk_slabsize / SLAB_SETSIZE;
1247 if (rsize & keg->uk_align)
1248 rsize = (rsize & ~keg->uk_align) + (keg->uk_align + 1);
1249 keg->uk_rsize = rsize;
1251 KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0 ||
1252 keg->uk_rsize < sizeof(struct pcpu),
1253 ("%s: size %u too large", __func__, keg->uk_rsize));
1255 if (keg->uk_flags & UMA_ZONE_REFCNT)
1256 rsize += sizeof(uint32_t);
1258 if (keg->uk_flags & UMA_ZONE_OFFPAGE)
1261 shsize = sizeof(struct uma_slab);
1263 keg->uk_ipers = (keg->uk_slabsize - shsize) / rsize;
1264 KASSERT(keg->uk_ipers > 0 && keg->uk_ipers <= SLAB_SETSIZE,
1265 ("%s: keg->uk_ipers %u", __func__, keg->uk_ipers));
1267 memused = keg->uk_ipers * rsize + shsize;
1268 wastedspace = keg->uk_slabsize - memused;
1271 * We can't do OFFPAGE if we're internal or if we've been
1272 * asked to not go to the VM for buckets. If we do this we
1273 * may end up going to the VM for slabs which we do not
1274 * want to do if we're UMA_ZFLAG_CACHEONLY as a result
1275 * of UMA_ZONE_VM, which clearly forbids it.
1277 if ((keg->uk_flags & UMA_ZFLAG_INTERNAL) ||
1278 (keg->uk_flags & UMA_ZFLAG_CACHEONLY))
1282 * See if using an OFFPAGE slab will limit our waste. Only do
1283 * this if it permits more items per-slab.
1285 * XXX We could try growing slabsize to limit max waste as well.
1286 * Historically this was not done because the VM could not
1287 * efficiently handle contiguous allocations.
1289 if ((wastedspace >= keg->uk_slabsize / UMA_MAX_WASTE) &&
1290 (keg->uk_ipers < (keg->uk_slabsize / keg->uk_rsize))) {
1291 keg->uk_ipers = keg->uk_slabsize / keg->uk_rsize;
1292 KASSERT(keg->uk_ipers > 0 && keg->uk_ipers <= SLAB_SETSIZE,
1293 ("%s: keg->uk_ipers %u", __func__, keg->uk_ipers));
1295 printf("UMA decided we need offpage slab headers for "
1296 "keg: %s, calculated wastedspace = %d, "
1297 "maximum wasted space allowed = %d, "
1298 "calculated ipers = %d, "
1299 "new wasted space = %d\n", keg->uk_name, wastedspace,
1300 keg->uk_slabsize / UMA_MAX_WASTE, keg->uk_ipers,
1301 keg->uk_slabsize - keg->uk_ipers * keg->uk_rsize);
1303 keg->uk_flags |= UMA_ZONE_OFFPAGE;
1306 if ((keg->uk_flags & UMA_ZONE_OFFPAGE) &&
1307 (keg->uk_flags & UMA_ZONE_VTOSLAB) == 0)
1308 keg->uk_flags |= UMA_ZONE_HASH;
1312 * Finish creating a large (> UMA_SLAB_SIZE) uma kegs. Just give in and do
1313 * OFFPAGE for now. When I can allow for more dynamic slab sizes this will be
1317 * keg The keg we should initialize
1323 keg_large_init(uma_keg_t keg)
1327 KASSERT(keg != NULL, ("Keg is null in keg_large_init"));
1328 KASSERT((keg->uk_flags & UMA_ZFLAG_CACHEONLY) == 0,
1329 ("keg_large_init: Cannot large-init a UMA_ZFLAG_CACHEONLY keg"));
1330 KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0,
1331 ("%s: Cannot large-init a UMA_ZONE_PCPU keg", __func__));
1333 keg->uk_ppera = howmany(keg->uk_size, PAGE_SIZE);
1334 keg->uk_slabsize = keg->uk_ppera * PAGE_SIZE;
1336 keg->uk_rsize = keg->uk_size;
1338 /* We can't do OFFPAGE if we're internal, bail out here. */
1339 if (keg->uk_flags & UMA_ZFLAG_INTERNAL)
1342 /* Check whether we have enough space to not do OFFPAGE. */
1343 if ((keg->uk_flags & UMA_ZONE_OFFPAGE) == 0) {
1344 shsize = sizeof(struct uma_slab);
1345 if (keg->uk_flags & UMA_ZONE_REFCNT)
1346 shsize += keg->uk_ipers * sizeof(uint32_t);
1347 if (shsize & UMA_ALIGN_PTR)
1348 shsize = (shsize & ~UMA_ALIGN_PTR) +
1349 (UMA_ALIGN_PTR + 1);
1351 if ((PAGE_SIZE * keg->uk_ppera) - keg->uk_rsize < shsize)
1352 keg->uk_flags |= UMA_ZONE_OFFPAGE;
1355 if ((keg->uk_flags & UMA_ZONE_OFFPAGE) &&
1356 (keg->uk_flags & UMA_ZONE_VTOSLAB) == 0)
1357 keg->uk_flags |= UMA_ZONE_HASH;
1361 keg_cachespread_init(uma_keg_t keg)
1368 KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0,
1369 ("%s: Cannot cachespread-init a UMA_ZONE_PCPU keg", __func__));
1371 alignsize = keg->uk_align + 1;
1372 rsize = keg->uk_size;
1374 * We want one item to start on every align boundary in a page. To
1375 * do this we will span pages. We will also extend the item by the
1376 * size of align if it is an even multiple of align. Otherwise, it
1377 * would fall on the same boundary every time.
1379 if (rsize & keg->uk_align)
1380 rsize = (rsize & ~keg->uk_align) + alignsize;
1381 if ((rsize & alignsize) == 0)
1383 trailer = rsize - keg->uk_size;
1384 pages = (rsize * (PAGE_SIZE / alignsize)) / PAGE_SIZE;
1385 pages = MIN(pages, (128 * 1024) / PAGE_SIZE);
1386 keg->uk_rsize = rsize;
1387 keg->uk_ppera = pages;
1388 keg->uk_slabsize = UMA_SLAB_SIZE;
1389 keg->uk_ipers = ((pages * PAGE_SIZE) + trailer) / rsize;
1390 keg->uk_flags |= UMA_ZONE_OFFPAGE | UMA_ZONE_VTOSLAB;
1391 KASSERT(keg->uk_ipers <= SLAB_SETSIZE,
1392 ("%s: keg->uk_ipers too high(%d) increase max_ipers", __func__,
1397 * Keg header ctor. This initializes all fields, locks, etc. And inserts
1398 * the keg onto the global keg list.
1400 * Arguments/Returns follow uma_ctor specifications
1401 * udata Actually uma_kctor_args
1404 keg_ctor(void *mem, int size, void *udata, int flags)
1406 struct uma_kctor_args *arg = udata;
1407 uma_keg_t keg = mem;
1411 keg->uk_size = arg->size;
1412 keg->uk_init = arg->uminit;
1413 keg->uk_fini = arg->fini;
1414 keg->uk_align = arg->align;
1416 keg->uk_reserve = 0;
1418 keg->uk_flags = arg->flags;
1419 keg->uk_allocf = page_alloc;
1420 keg->uk_freef = page_free;
1421 keg->uk_slabzone = NULL;
1424 * The master zone is passed to us at keg-creation time.
1427 keg->uk_name = zone->uz_name;
1429 if (arg->flags & UMA_ZONE_VM)
1430 keg->uk_flags |= UMA_ZFLAG_CACHEONLY;
1432 if (arg->flags & UMA_ZONE_ZINIT)
1433 keg->uk_init = zero_init;
1435 if (arg->flags & UMA_ZONE_REFCNT || arg->flags & UMA_ZONE_MALLOC)
1436 keg->uk_flags |= UMA_ZONE_VTOSLAB;
1438 if (arg->flags & UMA_ZONE_PCPU)
1440 keg->uk_flags |= UMA_ZONE_OFFPAGE;
1442 keg->uk_flags &= ~UMA_ZONE_PCPU;
1445 if (keg->uk_flags & UMA_ZONE_CACHESPREAD) {
1446 keg_cachespread_init(keg);
1447 } else if (keg->uk_flags & UMA_ZONE_REFCNT) {
1449 (UMA_SLAB_SIZE - sizeof(struct uma_slab_refcnt) -
1451 keg_large_init(keg);
1453 keg_small_init(keg);
1455 if (keg->uk_size > (UMA_SLAB_SIZE - sizeof(struct uma_slab)))
1456 keg_large_init(keg);
1458 keg_small_init(keg);
1461 if (keg->uk_flags & UMA_ZONE_OFFPAGE) {
1462 if (keg->uk_flags & UMA_ZONE_REFCNT) {
1463 if (keg->uk_ipers > uma_max_ipers_ref)
1464 panic("Too many ref items per zone: %d > %d\n",
1465 keg->uk_ipers, uma_max_ipers_ref);
1466 keg->uk_slabzone = slabrefzone;
1468 keg->uk_slabzone = slabzone;
1472 * If we haven't booted yet we need allocations to go through the
1473 * startup cache until the vm is ready.
1475 if (keg->uk_ppera == 1) {
1476 #ifdef UMA_MD_SMALL_ALLOC
1477 keg->uk_allocf = uma_small_alloc;
1478 keg->uk_freef = uma_small_free;
1480 if (booted < UMA_STARTUP)
1481 keg->uk_allocf = startup_alloc;
1483 if (booted < UMA_STARTUP2)
1484 keg->uk_allocf = startup_alloc;
1486 } else if (booted < UMA_STARTUP2 &&
1487 (keg->uk_flags & UMA_ZFLAG_INTERNAL))
1488 keg->uk_allocf = startup_alloc;
1491 * Initialize keg's lock
1493 KEG_LOCK_INIT(keg, (arg->flags & UMA_ZONE_MTXCLASS));
1496 * If we're putting the slab header in the actual page we need to
1497 * figure out where in each page it goes. This calculates a right
1498 * justified offset into the memory on an ALIGN_PTR boundary.
1500 if (!(keg->uk_flags & UMA_ZONE_OFFPAGE)) {
1503 /* Size of the slab struct and free list */
1504 totsize = sizeof(struct uma_slab);
1506 /* Size of the reference counts. */
1507 if (keg->uk_flags & UMA_ZONE_REFCNT)
1508 totsize += keg->uk_ipers * sizeof(uint32_t);
1510 if (totsize & UMA_ALIGN_PTR)
1511 totsize = (totsize & ~UMA_ALIGN_PTR) +
1512 (UMA_ALIGN_PTR + 1);
1513 keg->uk_pgoff = (PAGE_SIZE * keg->uk_ppera) - totsize;
1516 * The only way the following is possible is if with our
1517 * UMA_ALIGN_PTR adjustments we are now bigger than
1518 * UMA_SLAB_SIZE. I haven't checked whether this is
1519 * mathematically possible for all cases, so we make
1522 totsize = keg->uk_pgoff + sizeof(struct uma_slab);
1523 if (keg->uk_flags & UMA_ZONE_REFCNT)
1524 totsize += keg->uk_ipers * sizeof(uint32_t);
1525 if (totsize > PAGE_SIZE * keg->uk_ppera) {
1526 printf("zone %s ipers %d rsize %d size %d\n",
1527 zone->uz_name, keg->uk_ipers, keg->uk_rsize,
1529 panic("UMA slab won't fit.");
1533 if (keg->uk_flags & UMA_ZONE_HASH)
1534 hash_alloc(&keg->uk_hash);
1537 printf("UMA: %s(%p) size %d(%d) flags %#x ipers %d ppera %d out %d free %d\n",
1538 zone->uz_name, zone, keg->uk_size, keg->uk_rsize, keg->uk_flags,
1539 keg->uk_ipers, keg->uk_ppera,
1540 (keg->uk_ipers * keg->uk_pages) - keg->uk_free, keg->uk_free);
1543 LIST_INSERT_HEAD(&keg->uk_zones, zone, uz_link);
1546 LIST_INSERT_HEAD(&uma_kegs, keg, uk_link);
1547 mtx_unlock(&uma_mtx);
1552 * Zone header ctor. This initializes all fields, locks, etc.
1554 * Arguments/Returns follow uma_ctor specifications
1555 * udata Actually uma_zctor_args
1558 zone_ctor(void *mem, int size, void *udata, int flags)
1560 struct uma_zctor_args *arg = udata;
1561 uma_zone_t zone = mem;
1566 zone->uz_name = arg->name;
1567 zone->uz_ctor = arg->ctor;
1568 zone->uz_dtor = arg->dtor;
1569 zone->uz_slab = zone_fetch_slab;
1570 zone->uz_init = NULL;
1571 zone->uz_fini = NULL;
1572 zone->uz_allocs = 0;
1575 zone->uz_sleeps = 0;
1577 zone->uz_count_min = 0;
1579 zone->uz_warning = NULL;
1580 timevalclear(&zone->uz_ratecheck);
1583 ZONE_LOCK_INIT(zone, (arg->flags & UMA_ZONE_MTXCLASS));
1586 * This is a pure cache zone, no kegs.
1589 if (arg->flags & UMA_ZONE_VM)
1590 arg->flags |= UMA_ZFLAG_CACHEONLY;
1591 zone->uz_flags = arg->flags;
1592 zone->uz_size = arg->size;
1593 zone->uz_import = arg->import;
1594 zone->uz_release = arg->release;
1595 zone->uz_arg = arg->arg;
1596 zone->uz_lockptr = &zone->uz_lock;
1598 LIST_INSERT_HEAD(&uma_cachezones, zone, uz_link);
1599 mtx_unlock(&uma_mtx);
1604 * Use the regular zone/keg/slab allocator.
1606 zone->uz_import = (uma_import)zone_import;
1607 zone->uz_release = (uma_release)zone_release;
1608 zone->uz_arg = zone;
1610 if (arg->flags & UMA_ZONE_SECONDARY) {
1611 KASSERT(arg->keg != NULL, ("Secondary zone on zero'd keg"));
1612 zone->uz_init = arg->uminit;
1613 zone->uz_fini = arg->fini;
1614 zone->uz_lockptr = &keg->uk_lock;
1615 zone->uz_flags |= UMA_ZONE_SECONDARY;
1618 LIST_FOREACH(z, &keg->uk_zones, uz_link) {
1619 if (LIST_NEXT(z, uz_link) == NULL) {
1620 LIST_INSERT_AFTER(z, zone, uz_link);
1625 mtx_unlock(&uma_mtx);
1626 } else if (keg == NULL) {
1627 if ((keg = uma_kcreate(zone, arg->size, arg->uminit, arg->fini,
1628 arg->align, arg->flags)) == NULL)
1631 struct uma_kctor_args karg;
1634 /* We should only be here from uma_startup() */
1635 karg.size = arg->size;
1636 karg.uminit = arg->uminit;
1637 karg.fini = arg->fini;
1638 karg.align = arg->align;
1639 karg.flags = arg->flags;
1641 error = keg_ctor(arg->keg, sizeof(struct uma_keg), &karg,
1648 * Link in the first keg.
1650 zone->uz_klink.kl_keg = keg;
1651 LIST_INSERT_HEAD(&zone->uz_kegs, &zone->uz_klink, kl_link);
1652 zone->uz_lockptr = &keg->uk_lock;
1653 zone->uz_size = keg->uk_size;
1654 zone->uz_flags |= (keg->uk_flags &
1655 (UMA_ZONE_INHERIT | UMA_ZFLAG_INHERIT));
1658 * Some internal zones don't have room allocated for the per cpu
1659 * caches. If we're internal, bail out here.
1661 if (keg->uk_flags & UMA_ZFLAG_INTERNAL) {
1662 KASSERT((zone->uz_flags & UMA_ZONE_SECONDARY) == 0,
1663 ("Secondary zone requested UMA_ZFLAG_INTERNAL"));
1668 if ((arg->flags & UMA_ZONE_MAXBUCKET) == 0)
1669 zone->uz_count = bucket_select(zone->uz_size);
1671 zone->uz_count = BUCKET_MAX;
1672 zone->uz_count_min = zone->uz_count;
1678 * Keg header dtor. This frees all data, destroys locks, frees the hash
1679 * table and removes the keg from the global list.
1681 * Arguments/Returns follow uma_dtor specifications
1685 keg_dtor(void *arg, int size, void *udata)
1689 keg = (uma_keg_t)arg;
1691 if (keg->uk_free != 0) {
1692 printf("Freed UMA keg (%s) was not empty (%d items). "
1693 " Lost %d pages of memory.\n",
1694 keg->uk_name ? keg->uk_name : "",
1695 keg->uk_free, keg->uk_pages);
1699 hash_free(&keg->uk_hash);
1707 * Arguments/Returns follow uma_dtor specifications
1711 zone_dtor(void *arg, int size, void *udata)
1717 zone = (uma_zone_t)arg;
1718 keg = zone_first_keg(zone);
1720 if (!(zone->uz_flags & UMA_ZFLAG_INTERNAL))
1724 LIST_REMOVE(zone, uz_link);
1725 mtx_unlock(&uma_mtx);
1727 * XXX there are some races here where
1728 * the zone can be drained but zone lock
1729 * released and then refilled before we
1730 * remove it... we dont care for now
1732 zone_drain_wait(zone, M_WAITOK);
1734 * Unlink all of our kegs.
1736 while ((klink = LIST_FIRST(&zone->uz_kegs)) != NULL) {
1737 klink->kl_keg = NULL;
1738 LIST_REMOVE(klink, kl_link);
1739 if (klink == &zone->uz_klink)
1741 free(klink, M_TEMP);
1744 * We only destroy kegs from non secondary zones.
1746 if (keg != NULL && (zone->uz_flags & UMA_ZONE_SECONDARY) == 0) {
1748 LIST_REMOVE(keg, uk_link);
1749 mtx_unlock(&uma_mtx);
1750 zone_free_item(kegs, keg, NULL, SKIP_NONE);
1752 ZONE_LOCK_FINI(zone);
1756 * Traverses every zone in the system and calls a callback
1759 * zfunc A pointer to a function which accepts a zone
1766 zone_foreach(void (*zfunc)(uma_zone_t))
1772 LIST_FOREACH(keg, &uma_kegs, uk_link) {
1773 LIST_FOREACH(zone, &keg->uk_zones, uz_link)
1776 mtx_unlock(&uma_mtx);
1779 /* Public functions */
1782 uma_startup(void *bootmem, int boot_pages)
1784 struct uma_zctor_args args;
1790 printf("Creating uma keg headers zone and keg.\n");
1792 mtx_init(&uma_mtx, "UMA lock", NULL, MTX_DEF);
1794 /* "manually" create the initial zone */
1795 memset(&args, 0, sizeof(args));
1796 args.name = "UMA Kegs";
1797 args.size = sizeof(struct uma_keg);
1798 args.ctor = keg_ctor;
1799 args.dtor = keg_dtor;
1800 args.uminit = zero_init;
1802 args.keg = &masterkeg;
1803 args.align = 32 - 1;
1804 args.flags = UMA_ZFLAG_INTERNAL;
1805 /* The initial zone has no Per cpu queues so it's smaller */
1806 zone_ctor(kegs, sizeof(struct uma_zone), &args, M_WAITOK);
1809 printf("Filling boot free list.\n");
1811 for (i = 0; i < boot_pages; i++) {
1812 slab = (uma_slab_t)((uint8_t *)bootmem + (i * UMA_SLAB_SIZE));
1813 slab->us_data = (uint8_t *)slab;
1814 slab->us_flags = UMA_SLAB_BOOT;
1815 LIST_INSERT_HEAD(&uma_boot_pages, slab, us_link);
1817 mtx_init(&uma_boot_pages_mtx, "UMA boot pages", NULL, MTX_DEF);
1820 printf("Creating uma zone headers zone and keg.\n");
1822 args.name = "UMA Zones";
1823 args.size = sizeof(struct uma_zone) +
1824 (sizeof(struct uma_cache) * (mp_maxid + 1));
1825 args.ctor = zone_ctor;
1826 args.dtor = zone_dtor;
1827 args.uminit = zero_init;
1830 args.align = 32 - 1;
1831 args.flags = UMA_ZFLAG_INTERNAL;
1832 /* The initial zone has no Per cpu queues so it's smaller */
1833 zone_ctor(zones, sizeof(struct uma_zone), &args, M_WAITOK);
1836 printf("Initializing pcpu cache locks.\n");
1839 printf("Creating slab and hash zones.\n");
1842 /* Now make a zone for slab headers */
1843 slabzone = uma_zcreate("UMA Slabs",
1844 sizeof(struct uma_slab),
1845 NULL, NULL, NULL, NULL,
1846 UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
1849 * We also create a zone for the bigger slabs with reference
1850 * counts in them, to accomodate UMA_ZONE_REFCNT zones.
1852 slabsize = sizeof(struct uma_slab_refcnt);
1853 slabsize += uma_max_ipers_ref * sizeof(uint32_t);
1854 slabrefzone = uma_zcreate("UMA RCntSlabs",
1856 NULL, NULL, NULL, NULL,
1858 UMA_ZFLAG_INTERNAL);
1860 hashzone = uma_zcreate("UMA Hash",
1861 sizeof(struct slabhead *) * UMA_HASH_SIZE_INIT,
1862 NULL, NULL, NULL, NULL,
1863 UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
1867 booted = UMA_STARTUP;
1870 printf("UMA startup complete.\n");
1878 booted = UMA_STARTUP2;
1881 printf("UMA startup2 complete.\n");
1886 * Initialize our callout handle
1894 printf("Starting callout.\n");
1896 callout_init(&uma_callout, CALLOUT_MPSAFE);
1897 callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL);
1899 printf("UMA startup3 complete.\n");
1904 uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit, uma_fini fini,
1905 int align, uint32_t flags)
1907 struct uma_kctor_args args;
1910 args.uminit = uminit;
1912 args.align = (align == UMA_ALIGN_CACHE) ? uma_align_cache : align;
1915 return (zone_alloc_item(kegs, &args, M_WAITOK));
1920 uma_set_align(int align)
1923 if (align != UMA_ALIGN_CACHE)
1924 uma_align_cache = align;
1929 uma_zcreate(const char *name, size_t size, uma_ctor ctor, uma_dtor dtor,
1930 uma_init uminit, uma_fini fini, int align, uint32_t flags)
1933 struct uma_zctor_args args;
1935 /* This stuff is essential for the zone ctor */
1936 memset(&args, 0, sizeof(args));
1941 args.uminit = uminit;
1947 return (zone_alloc_item(zones, &args, M_WAITOK));
1952 uma_zsecond_create(char *name, uma_ctor ctor, uma_dtor dtor,
1953 uma_init zinit, uma_fini zfini, uma_zone_t master)
1955 struct uma_zctor_args args;
1958 keg = zone_first_keg(master);
1959 memset(&args, 0, sizeof(args));
1961 args.size = keg->uk_size;
1964 args.uminit = zinit;
1966 args.align = keg->uk_align;
1967 args.flags = keg->uk_flags | UMA_ZONE_SECONDARY;
1970 /* XXX Attaches only one keg of potentially many. */
1971 return (zone_alloc_item(zones, &args, M_WAITOK));
1976 uma_zcache_create(char *name, int size, uma_ctor ctor, uma_dtor dtor,
1977 uma_init zinit, uma_fini zfini, uma_import zimport,
1978 uma_release zrelease, void *arg, int flags)
1980 struct uma_zctor_args args;
1982 memset(&args, 0, sizeof(args));
1987 args.uminit = zinit;
1989 args.import = zimport;
1990 args.release = zrelease;
1995 return (zone_alloc_item(zones, &args, M_WAITOK));
1999 zone_lock_pair(uma_zone_t a, uma_zone_t b)
2003 mtx_lock_flags(b->uz_lockptr, MTX_DUPOK);
2006 mtx_lock_flags(a->uz_lockptr, MTX_DUPOK);
2011 zone_unlock_pair(uma_zone_t a, uma_zone_t b)
2019 uma_zsecond_add(uma_zone_t zone, uma_zone_t master)
2026 klink = malloc(sizeof(*klink), M_TEMP, M_WAITOK | M_ZERO);
2028 zone_lock_pair(zone, master);
2030 * zone must use vtoslab() to resolve objects and must already be
2033 if ((zone->uz_flags & (UMA_ZONE_VTOSLAB | UMA_ZONE_SECONDARY))
2034 != (UMA_ZONE_VTOSLAB | UMA_ZONE_SECONDARY)) {
2039 * The new master must also use vtoslab().
2041 if ((zone->uz_flags & UMA_ZONE_VTOSLAB) != UMA_ZONE_VTOSLAB) {
2046 * Both must either be refcnt, or not be refcnt.
2048 if ((zone->uz_flags & UMA_ZONE_REFCNT) !=
2049 (master->uz_flags & UMA_ZONE_REFCNT)) {
2054 * The underlying object must be the same size. rsize
2057 if (master->uz_size != zone->uz_size) {
2062 * Put it at the end of the list.
2064 klink->kl_keg = zone_first_keg(master);
2065 LIST_FOREACH(kl, &zone->uz_kegs, kl_link) {
2066 if (LIST_NEXT(kl, kl_link) == NULL) {
2067 LIST_INSERT_AFTER(kl, klink, kl_link);
2072 zone->uz_flags |= UMA_ZFLAG_MULTI;
2073 zone->uz_slab = zone_fetch_slab_multi;
2076 zone_unlock_pair(zone, master);
2078 free(klink, M_TEMP);
2086 uma_zdestroy(uma_zone_t zone)
2089 zone_free_item(zones, zone, NULL, SKIP_NONE);
2094 uma_zalloc_arg(uma_zone_t zone, void *udata, int flags)
2098 uma_bucket_t bucket;
2102 /* This is the fast path allocation */
2103 #ifdef UMA_DEBUG_ALLOC_1
2104 printf("Allocating one item from %s(%p)\n", zone->uz_name, zone);
2106 CTR3(KTR_UMA, "uma_zalloc_arg thread %x zone %s flags %d", curthread,
2107 zone->uz_name, flags);
2109 if (flags & M_WAITOK) {
2110 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
2111 "uma_zalloc_arg: zone \"%s\"", zone->uz_name);
2113 #ifdef DEBUG_MEMGUARD
2114 if (memguard_cmp_zone(zone)) {
2115 item = memguard_alloc(zone->uz_size, flags);
2118 * Avoid conflict with the use-after-free
2119 * protecting infrastructure from INVARIANTS.
2121 if (zone->uz_init != NULL &&
2122 zone->uz_init != mtrash_init &&
2123 zone->uz_init(item, zone->uz_size, flags) != 0)
2125 if (zone->uz_ctor != NULL &&
2126 zone->uz_ctor != mtrash_ctor &&
2127 zone->uz_ctor(item, zone->uz_size, udata,
2129 zone->uz_fini(item, zone->uz_size);
2134 /* This is unfortunate but should not be fatal. */
2138 * If possible, allocate from the per-CPU cache. There are two
2139 * requirements for safe access to the per-CPU cache: (1) the thread
2140 * accessing the cache must not be preempted or yield during access,
2141 * and (2) the thread must not migrate CPUs without switching which
2142 * cache it accesses. We rely on a critical section to prevent
2143 * preemption and migration. We release the critical section in
2144 * order to acquire the zone mutex if we are unable to allocate from
2145 * the current cache; when we re-acquire the critical section, we
2146 * must detect and handle migration if it has occurred.
2150 cache = &zone->uz_cpu[cpu];
2153 bucket = cache->uc_allocbucket;
2154 if (bucket != NULL && bucket->ub_cnt > 0) {
2156 item = bucket->ub_bucket[bucket->ub_cnt];
2158 bucket->ub_bucket[bucket->ub_cnt] = NULL;
2160 KASSERT(item != NULL, ("uma_zalloc: Bucket pointer mangled."));
2163 if (zone->uz_ctor != NULL &&
2164 zone->uz_ctor(item, zone->uz_size, udata, flags) != 0) {
2165 atomic_add_long(&zone->uz_fails, 1);
2166 zone_free_item(zone, item, udata, SKIP_DTOR);
2170 uma_dbg_alloc(zone, NULL, item);
2173 uma_zero_item(item, zone);
2178 * We have run out of items in our alloc bucket.
2179 * See if we can switch with our free bucket.
2181 bucket = cache->uc_freebucket;
2182 if (bucket != NULL && bucket->ub_cnt > 0) {
2183 #ifdef UMA_DEBUG_ALLOC
2184 printf("uma_zalloc: Swapping empty with alloc.\n");
2186 cache->uc_freebucket = cache->uc_allocbucket;
2187 cache->uc_allocbucket = bucket;
2192 * Discard any empty allocation bucket while we hold no locks.
2194 bucket = cache->uc_allocbucket;
2195 cache->uc_allocbucket = NULL;
2198 bucket_free(zone, bucket, udata);
2200 /* Short-circuit for zones without buckets and low memory. */
2201 if (zone->uz_count == 0 || bucketdisable)
2205 * Attempt to retrieve the item from the per-CPU cache has failed, so
2206 * we must go back to the zone. This requires the zone lock, so we
2207 * must drop the critical section, then re-acquire it when we go back
2208 * to the cache. Since the critical section is released, we may be
2209 * preempted or migrate. As such, make sure not to maintain any
2210 * thread-local state specific to the cache from prior to releasing
2211 * the critical section.
2214 if (ZONE_TRYLOCK(zone) == 0) {
2215 /* Record contention to size the buckets. */
2221 cache = &zone->uz_cpu[cpu];
2224 * Since we have locked the zone we may as well send back our stats.
2226 atomic_add_long(&zone->uz_allocs, cache->uc_allocs);
2227 atomic_add_long(&zone->uz_frees, cache->uc_frees);
2228 cache->uc_allocs = 0;
2229 cache->uc_frees = 0;
2231 /* See if we lost the race to fill the cache. */
2232 if (cache->uc_allocbucket != NULL) {
2238 * Check the zone's cache of buckets.
2240 if ((bucket = LIST_FIRST(&zone->uz_buckets)) != NULL) {
2241 KASSERT(bucket->ub_cnt != 0,
2242 ("uma_zalloc_arg: Returning an empty bucket."));
2244 LIST_REMOVE(bucket, ub_link);
2245 cache->uc_allocbucket = bucket;
2249 /* We are no longer associated with this CPU. */
2253 * We bump the uz count when the cache size is insufficient to
2254 * handle the working set.
2256 if (lockfail && zone->uz_count < BUCKET_MAX)
2261 * Now lets just fill a bucket and put it on the free list. If that
2262 * works we'll restart the allocation from the begining and it
2263 * will use the just filled bucket.
2265 bucket = zone_alloc_bucket(zone, udata, flags);
2266 if (bucket != NULL) {
2270 cache = &zone->uz_cpu[cpu];
2272 * See if we lost the race or were migrated. Cache the
2273 * initialized bucket to make this less likely or claim
2274 * the memory directly.
2276 if (cache->uc_allocbucket == NULL)
2277 cache->uc_allocbucket = bucket;
2279 LIST_INSERT_HEAD(&zone->uz_buckets, bucket, ub_link);
2285 * We may not be able to get a bucket so return an actual item.
2288 printf("uma_zalloc_arg: Bucketzone returned NULL\n");
2292 item = zone_alloc_item(zone, udata, flags);
2298 keg_fetch_slab(uma_keg_t keg, uma_zone_t zone, int flags)
2303 mtx_assert(&keg->uk_lock, MA_OWNED);
2306 if ((flags & M_USE_RESERVE) == 0)
2307 reserve = keg->uk_reserve;
2311 * Find a slab with some space. Prefer slabs that are partially
2312 * used over those that are totally full. This helps to reduce
2315 if (keg->uk_free > reserve) {
2316 if (!LIST_EMPTY(&keg->uk_part_slab)) {
2317 slab = LIST_FIRST(&keg->uk_part_slab);
2319 slab = LIST_FIRST(&keg->uk_free_slab);
2320 LIST_REMOVE(slab, us_link);
2321 LIST_INSERT_HEAD(&keg->uk_part_slab, slab,
2324 MPASS(slab->us_keg == keg);
2329 * M_NOVM means don't ask at all!
2334 if (keg->uk_maxpages && keg->uk_pages >= keg->uk_maxpages) {
2335 keg->uk_flags |= UMA_ZFLAG_FULL;
2337 * If this is not a multi-zone, set the FULL bit.
2338 * Otherwise slab_multi() takes care of it.
2340 if ((zone->uz_flags & UMA_ZFLAG_MULTI) == 0) {
2341 zone->uz_flags |= UMA_ZFLAG_FULL;
2342 zone_log_warning(zone);
2344 if (flags & M_NOWAIT)
2347 msleep(keg, &keg->uk_lock, PVM, "keglimit", 0);
2350 slab = keg_alloc_slab(keg, zone, flags);
2352 * If we got a slab here it's safe to mark it partially used
2353 * and return. We assume that the caller is going to remove
2354 * at least one item.
2357 MPASS(slab->us_keg == keg);
2358 LIST_INSERT_HEAD(&keg->uk_part_slab, slab, us_link);
2362 * We might not have been able to get a slab but another cpu
2363 * could have while we were unlocked. Check again before we
2372 zone_fetch_slab(uma_zone_t zone, uma_keg_t keg, int flags)
2377 keg = zone_first_keg(zone);
2382 slab = keg_fetch_slab(keg, zone, flags);
2385 if (flags & (M_NOWAIT | M_NOVM))
2393 * uma_zone_fetch_slab_multi: Fetches a slab from one available keg. Returns
2394 * with the keg locked. On NULL no lock is held.
2396 * The last pointer is used to seed the search. It is not required.
2399 zone_fetch_slab_multi(uma_zone_t zone, uma_keg_t last, int rflags)
2409 * Don't wait on the first pass. This will skip limit tests
2410 * as well. We don't want to block if we can find a provider
2413 flags = (rflags & ~M_WAITOK) | M_NOWAIT;
2415 * Use the last slab allocated as a hint for where to start
2419 slab = keg_fetch_slab(last, zone, flags);
2425 * Loop until we have a slab incase of transient failures
2426 * while M_WAITOK is specified. I'm not sure this is 100%
2427 * required but we've done it for so long now.
2433 * Search the available kegs for slabs. Be careful to hold the
2434 * correct lock while calling into the keg layer.
2436 LIST_FOREACH(klink, &zone->uz_kegs, kl_link) {
2437 keg = klink->kl_keg;
2439 if ((keg->uk_flags & UMA_ZFLAG_FULL) == 0) {
2440 slab = keg_fetch_slab(keg, zone, flags);
2444 if (keg->uk_flags & UMA_ZFLAG_FULL)
2450 if (rflags & (M_NOWAIT | M_NOVM))
2454 * All kegs are full. XXX We can't atomically check all kegs
2455 * and sleep so just sleep for a short period and retry.
2457 if (full && !empty) {
2459 zone->uz_flags |= UMA_ZFLAG_FULL;
2461 zone_log_warning(zone);
2462 msleep(zone, zone->uz_lockptr, PVM,
2463 "zonelimit", hz/100);
2464 zone->uz_flags &= ~UMA_ZFLAG_FULL;
2473 slab_alloc_item(uma_keg_t keg, uma_slab_t slab)
2478 MPASS(keg == slab->us_keg);
2479 mtx_assert(&keg->uk_lock, MA_OWNED);
2481 freei = BIT_FFS(SLAB_SETSIZE, &slab->us_free) - 1;
2482 BIT_CLR(SLAB_SETSIZE, freei, &slab->us_free);
2483 item = slab->us_data + (keg->uk_rsize * freei);
2484 slab->us_freecount--;
2487 /* Move this slab to the full list */
2488 if (slab->us_freecount == 0) {
2489 LIST_REMOVE(slab, us_link);
2490 LIST_INSERT_HEAD(&keg->uk_full_slab, slab, us_link);
2497 zone_import(uma_zone_t zone, void **bucket, int max, int flags)
2505 /* Try to keep the buckets totally full */
2506 for (i = 0; i < max; ) {
2507 if ((slab = zone->uz_slab(zone, keg, flags)) == NULL)
2510 while (slab->us_freecount && i < max) {
2511 bucket[i++] = slab_alloc_item(keg, slab);
2512 if (keg->uk_free <= keg->uk_reserve)
2515 /* Don't grab more than one slab at a time. */
2526 zone_alloc_bucket(uma_zone_t zone, void *udata, int flags)
2528 uma_bucket_t bucket;
2531 /* Don't wait for buckets, preserve caller's NOVM setting. */
2532 bucket = bucket_alloc(zone, udata, M_NOWAIT | (flags & M_NOVM));
2536 max = MIN(bucket->ub_entries, zone->uz_count);
2537 bucket->ub_cnt = zone->uz_import(zone->uz_arg, bucket->ub_bucket,
2541 * Initialize the memory if necessary.
2543 if (bucket->ub_cnt != 0 && zone->uz_init != NULL) {
2546 for (i = 0; i < bucket->ub_cnt; i++)
2547 if (zone->uz_init(bucket->ub_bucket[i], zone->uz_size,
2551 * If we couldn't initialize the whole bucket, put the
2552 * rest back onto the freelist.
2554 if (i != bucket->ub_cnt) {
2555 zone->uz_release(zone->uz_arg, &bucket->ub_bucket[i],
2556 bucket->ub_cnt - i);
2558 bzero(&bucket->ub_bucket[i],
2559 sizeof(void *) * (bucket->ub_cnt - i));
2565 if (bucket->ub_cnt == 0) {
2566 bucket_free(zone, bucket, udata);
2567 atomic_add_long(&zone->uz_fails, 1);
2575 * Allocates a single item from a zone.
2578 * zone The zone to alloc for.
2579 * udata The data to be passed to the constructor.
2580 * flags M_WAITOK, M_NOWAIT, M_ZERO.
2583 * NULL if there is no memory and M_NOWAIT is set
2584 * An item if successful
2588 zone_alloc_item(uma_zone_t zone, void *udata, int flags)
2594 #ifdef UMA_DEBUG_ALLOC
2595 printf("INTERNAL: Allocating one item from %s(%p)\n", zone->uz_name, zone);
2597 if (zone->uz_import(zone->uz_arg, &item, 1, flags) != 1)
2599 atomic_add_long(&zone->uz_allocs, 1);
2602 * We have to call both the zone's init (not the keg's init)
2603 * and the zone's ctor. This is because the item is going from
2604 * a keg slab directly to the user, and the user is expecting it
2605 * to be both zone-init'd as well as zone-ctor'd.
2607 if (zone->uz_init != NULL) {
2608 if (zone->uz_init(item, zone->uz_size, flags) != 0) {
2609 zone_free_item(zone, item, udata, SKIP_FINI);
2613 if (zone->uz_ctor != NULL) {
2614 if (zone->uz_ctor(item, zone->uz_size, udata, flags) != 0) {
2615 zone_free_item(zone, item, udata, SKIP_DTOR);
2620 uma_dbg_alloc(zone, NULL, item);
2623 uma_zero_item(item, zone);
2628 atomic_add_long(&zone->uz_fails, 1);
2634 uma_zfree_arg(uma_zone_t zone, void *item, void *udata)
2637 uma_bucket_t bucket;
2641 #ifdef UMA_DEBUG_ALLOC_1
2642 printf("Freeing item %p to %s(%p)\n", item, zone->uz_name, zone);
2644 CTR2(KTR_UMA, "uma_zfree_arg thread %x zone %s", curthread,
2647 /* uma_zfree(..., NULL) does nothing, to match free(9). */
2650 #ifdef DEBUG_MEMGUARD
2651 if (is_memguard_addr(item)) {
2652 if (zone->uz_dtor != NULL && zone->uz_dtor != mtrash_dtor)
2653 zone->uz_dtor(item, zone->uz_size, udata);
2654 if (zone->uz_fini != NULL && zone->uz_fini != mtrash_fini)
2655 zone->uz_fini(item, zone->uz_size);
2656 memguard_free(item);
2661 if (zone->uz_flags & UMA_ZONE_MALLOC)
2662 uma_dbg_free(zone, udata, item);
2664 uma_dbg_free(zone, NULL, item);
2666 if (zone->uz_dtor != NULL)
2667 zone->uz_dtor(item, zone->uz_size, udata);
2670 * The race here is acceptable. If we miss it we'll just have to wait
2671 * a little longer for the limits to be reset.
2673 if (zone->uz_flags & UMA_ZFLAG_FULL)
2677 * If possible, free to the per-CPU cache. There are two
2678 * requirements for safe access to the per-CPU cache: (1) the thread
2679 * accessing the cache must not be preempted or yield during access,
2680 * and (2) the thread must not migrate CPUs without switching which
2681 * cache it accesses. We rely on a critical section to prevent
2682 * preemption and migration. We release the critical section in
2683 * order to acquire the zone mutex if we are unable to free to the
2684 * current cache; when we re-acquire the critical section, we must
2685 * detect and handle migration if it has occurred.
2690 cache = &zone->uz_cpu[cpu];
2694 * Try to free into the allocbucket first to give LIFO ordering
2695 * for cache-hot datastructures. Spill over into the freebucket
2696 * if necessary. Alloc will swap them if one runs dry.
2698 bucket = cache->uc_allocbucket;
2699 if (bucket == NULL || bucket->ub_cnt >= bucket->ub_entries)
2700 bucket = cache->uc_freebucket;
2701 if (bucket != NULL && bucket->ub_cnt < bucket->ub_entries) {
2702 KASSERT(bucket->ub_bucket[bucket->ub_cnt] == NULL,
2703 ("uma_zfree: Freeing to non free bucket index."));
2704 bucket->ub_bucket[bucket->ub_cnt] = item;
2712 * We must go back the zone, which requires acquiring the zone lock,
2713 * which in turn means we must release and re-acquire the critical
2714 * section. Since the critical section is released, we may be
2715 * preempted or migrate. As such, make sure not to maintain any
2716 * thread-local state specific to the cache from prior to releasing
2717 * the critical section.
2720 if (zone->uz_count == 0 || bucketdisable)
2724 if (ZONE_TRYLOCK(zone) == 0) {
2725 /* Record contention to size the buckets. */
2731 cache = &zone->uz_cpu[cpu];
2734 * Since we have locked the zone we may as well send back our stats.
2736 atomic_add_long(&zone->uz_allocs, cache->uc_allocs);
2737 atomic_add_long(&zone->uz_frees, cache->uc_frees);
2738 cache->uc_allocs = 0;
2739 cache->uc_frees = 0;
2741 bucket = cache->uc_freebucket;
2742 if (bucket != NULL && bucket->ub_cnt < bucket->ub_entries) {
2746 cache->uc_freebucket = NULL;
2748 /* Can we throw this on the zone full list? */
2749 if (bucket != NULL) {
2750 #ifdef UMA_DEBUG_ALLOC
2751 printf("uma_zfree: Putting old bucket on the free list.\n");
2753 /* ub_cnt is pointing to the last free item */
2754 KASSERT(bucket->ub_cnt != 0,
2755 ("uma_zfree: Attempting to insert an empty bucket onto the full list.\n"));
2756 LIST_INSERT_HEAD(&zone->uz_buckets, bucket, ub_link);
2759 /* We are no longer associated with this CPU. */
2763 * We bump the uz count when the cache size is insufficient to
2764 * handle the working set.
2766 if (lockfail && zone->uz_count < BUCKET_MAX)
2770 #ifdef UMA_DEBUG_ALLOC
2771 printf("uma_zfree: Allocating new free bucket.\n");
2773 bucket = bucket_alloc(zone, udata, M_NOWAIT);
2777 cache = &zone->uz_cpu[cpu];
2778 if (cache->uc_freebucket == NULL) {
2779 cache->uc_freebucket = bucket;
2783 * We lost the race, start over. We have to drop our
2784 * critical section to free the bucket.
2787 bucket_free(zone, bucket, udata);
2792 * If nothing else caught this, we'll just do an internal free.
2795 zone_free_item(zone, item, udata, SKIP_DTOR);
2801 slab_free_item(uma_keg_t keg, uma_slab_t slab, void *item)
2805 mtx_assert(&keg->uk_lock, MA_OWNED);
2806 MPASS(keg == slab->us_keg);
2808 /* Do we need to remove from any lists? */
2809 if (slab->us_freecount+1 == keg->uk_ipers) {
2810 LIST_REMOVE(slab, us_link);
2811 LIST_INSERT_HEAD(&keg->uk_free_slab, slab, us_link);
2812 } else if (slab->us_freecount == 0) {
2813 LIST_REMOVE(slab, us_link);
2814 LIST_INSERT_HEAD(&keg->uk_part_slab, slab, us_link);
2817 /* Slab management. */
2818 freei = ((uintptr_t)item - (uintptr_t)slab->us_data) / keg->uk_rsize;
2819 BIT_SET(SLAB_SETSIZE, freei, &slab->us_free);
2820 slab->us_freecount++;
2822 /* Keg statistics. */
2827 zone_release(uma_zone_t zone, void **bucket, int cnt)
2837 keg = zone_first_keg(zone);
2839 for (i = 0; i < cnt; i++) {
2841 if (!(zone->uz_flags & UMA_ZONE_VTOSLAB)) {
2842 mem = (uint8_t *)((uintptr_t)item & (~UMA_SLAB_MASK));
2843 if (zone->uz_flags & UMA_ZONE_HASH) {
2844 slab = hash_sfind(&keg->uk_hash, mem);
2846 mem += keg->uk_pgoff;
2847 slab = (uma_slab_t)mem;
2850 slab = vtoslab((vm_offset_t)item);
2851 if (slab->us_keg != keg) {
2857 slab_free_item(keg, slab, item);
2858 if (keg->uk_flags & UMA_ZFLAG_FULL) {
2859 if (keg->uk_pages < keg->uk_maxpages) {
2860 keg->uk_flags &= ~UMA_ZFLAG_FULL;
2865 * We can handle one more allocation. Since we're
2866 * clearing ZFLAG_FULL, wake up all procs blocked
2867 * on pages. This should be uncommon, so keeping this
2868 * simple for now (rather than adding count of blocked
2877 zone->uz_flags &= ~UMA_ZFLAG_FULL;
2885 * Frees a single item to any zone.
2888 * zone The zone to free to
2889 * item The item we're freeing
2890 * udata User supplied data for the dtor
2891 * skip Skip dtors and finis
2894 zone_free_item(uma_zone_t zone, void *item, void *udata, enum zfreeskip skip)
2898 if (skip == SKIP_NONE) {
2899 if (zone->uz_flags & UMA_ZONE_MALLOC)
2900 uma_dbg_free(zone, udata, item);
2902 uma_dbg_free(zone, NULL, item);
2905 if (skip < SKIP_DTOR && zone->uz_dtor)
2906 zone->uz_dtor(item, zone->uz_size, udata);
2908 if (skip < SKIP_FINI && zone->uz_fini)
2909 zone->uz_fini(item, zone->uz_size);
2911 atomic_add_long(&zone->uz_frees, 1);
2912 zone->uz_release(zone->uz_arg, &item, 1);
2917 uma_zone_set_max(uma_zone_t zone, int nitems)
2921 keg = zone_first_keg(zone);
2925 keg->uk_maxpages = (nitems / keg->uk_ipers) * keg->uk_ppera;
2926 if (keg->uk_maxpages * keg->uk_ipers < nitems)
2927 keg->uk_maxpages += keg->uk_ppera;
2928 nitems = keg->uk_maxpages * keg->uk_ipers;
2936 uma_zone_get_max(uma_zone_t zone)
2941 keg = zone_first_keg(zone);
2945 nitems = keg->uk_maxpages * keg->uk_ipers;
2953 uma_zone_set_warning(uma_zone_t zone, const char *warning)
2957 zone->uz_warning = warning;
2963 uma_zone_get_cur(uma_zone_t zone)
2969 nitems = zone->uz_allocs - zone->uz_frees;
2972 * See the comment in sysctl_vm_zone_stats() regarding the
2973 * safety of accessing the per-cpu caches. With the zone lock
2974 * held, it is safe, but can potentially result in stale data.
2976 nitems += zone->uz_cpu[i].uc_allocs -
2977 zone->uz_cpu[i].uc_frees;
2981 return (nitems < 0 ? 0 : nitems);
2986 uma_zone_set_init(uma_zone_t zone, uma_init uminit)
2990 keg = zone_first_keg(zone);
2991 KASSERT(keg != NULL, ("uma_zone_set_init: Invalid zone type"));
2993 KASSERT(keg->uk_pages == 0,
2994 ("uma_zone_set_init on non-empty keg"));
2995 keg->uk_init = uminit;
3001 uma_zone_set_fini(uma_zone_t zone, uma_fini fini)
3005 keg = zone_first_keg(zone);
3006 KASSERT(keg != NULL, ("uma_zone_set_init: Invalid zone type"));
3008 KASSERT(keg->uk_pages == 0,
3009 ("uma_zone_set_fini on non-empty keg"));
3010 keg->uk_fini = fini;
3016 uma_zone_set_zinit(uma_zone_t zone, uma_init zinit)
3020 KASSERT(zone_first_keg(zone)->uk_pages == 0,
3021 ("uma_zone_set_zinit on non-empty keg"));
3022 zone->uz_init = zinit;
3028 uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini)
3032 KASSERT(zone_first_keg(zone)->uk_pages == 0,
3033 ("uma_zone_set_zfini on non-empty keg"));
3034 zone->uz_fini = zfini;
3039 /* XXX uk_freef is not actually used with the zone locked */
3041 uma_zone_set_freef(uma_zone_t zone, uma_free freef)
3045 keg = zone_first_keg(zone);
3046 KASSERT(keg != NULL, ("uma_zone_set_init: Invalid zone type"));
3048 keg->uk_freef = freef;
3053 /* XXX uk_allocf is not actually used with the zone locked */
3055 uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf)
3059 keg = zone_first_keg(zone);
3061 keg->uk_allocf = allocf;
3067 uma_zone_reserve(uma_zone_t zone, int items)
3071 keg = zone_first_keg(zone);
3075 keg->uk_reserve = items;
3083 uma_zone_reserve_kva(uma_zone_t zone, int count)
3089 keg = zone_first_keg(zone);
3092 pages = count / keg->uk_ipers;
3094 if (pages * keg->uk_ipers < count)
3097 #ifdef UMA_MD_SMALL_ALLOC
3098 if (keg->uk_ppera > 1) {
3102 kva = kva_alloc(pages * UMA_SLAB_SIZE);
3110 keg->uk_maxpages = pages;
3111 #ifdef UMA_MD_SMALL_ALLOC
3112 keg->uk_allocf = (keg->uk_ppera > 1) ? noobj_alloc : uma_small_alloc;
3114 keg->uk_allocf = noobj_alloc;
3116 keg->uk_flags |= UMA_ZONE_NOFREE;
3124 uma_prealloc(uma_zone_t zone, int items)
3130 keg = zone_first_keg(zone);
3134 slabs = items / keg->uk_ipers;
3135 if (slabs * keg->uk_ipers < items)
3138 slab = keg_alloc_slab(keg, zone, M_WAITOK);
3141 MPASS(slab->us_keg == keg);
3142 LIST_INSERT_HEAD(&keg->uk_free_slab, slab, us_link);
3150 uma_find_refcnt(uma_zone_t zone, void *item)
3152 uma_slabrefcnt_t slabref;
3158 slab = vtoslab((vm_offset_t)item & (~UMA_SLAB_MASK));
3159 slabref = (uma_slabrefcnt_t)slab;
3161 KASSERT(keg->uk_flags & UMA_ZONE_REFCNT,
3162 ("uma_find_refcnt(): zone possibly not UMA_ZONE_REFCNT"));
3163 idx = ((uintptr_t)item - (uintptr_t)slab->us_data) / keg->uk_rsize;
3164 refcnt = &slabref->us_refcnt[idx];
3173 printf("UMA: vm asked us to release pages!\n");
3176 zone_foreach(zone_drain);
3177 if (vm_page_count_min()) {
3178 cache_drain_safe(NULL);
3179 zone_foreach(zone_drain);
3182 * Some slabs may have been freed but this zone will be visited early
3183 * we visit again so that we can free pages that are empty once other
3184 * zones are drained. We have to do the same for buckets.
3186 zone_drain(slabzone);
3187 zone_drain(slabrefzone);
3188 bucket_zone_drain();
3193 uma_zone_exhausted(uma_zone_t zone)
3198 full = (zone->uz_flags & UMA_ZFLAG_FULL);
3204 uma_zone_exhausted_nolock(uma_zone_t zone)
3206 return (zone->uz_flags & UMA_ZFLAG_FULL);
3210 uma_large_malloc(int size, int wait)
3216 slab = zone_alloc_item(slabzone, NULL, wait);
3219 mem = page_alloc(NULL, size, &flags, wait);
3221 vsetslab((vm_offset_t)mem, slab);
3222 slab->us_data = mem;
3223 slab->us_flags = flags | UMA_SLAB_MALLOC;
3224 slab->us_size = size;
3226 zone_free_item(slabzone, slab, NULL, SKIP_NONE);
3233 uma_large_free(uma_slab_t slab)
3236 page_free(slab->us_data, slab->us_size, slab->us_flags);
3237 zone_free_item(slabzone, slab, NULL, SKIP_NONE);
3241 uma_zero_item(void *item, uma_zone_t zone)
3244 if (zone->uz_flags & UMA_ZONE_PCPU) {
3245 for (int i = 0; i < mp_ncpus; i++)
3246 bzero(zpcpu_get_cpu(item, i), zone->uz_size);
3248 bzero(item, zone->uz_size);
3252 uma_print_stats(void)
3254 zone_foreach(uma_print_zone);
3258 slab_print(uma_slab_t slab)
3260 printf("slab: keg %p, data %p, freecount %d\n",
3261 slab->us_keg, slab->us_data, slab->us_freecount);
3265 cache_print(uma_cache_t cache)
3267 printf("alloc: %p(%d), free: %p(%d)\n",
3268 cache->uc_allocbucket,
3269 cache->uc_allocbucket?cache->uc_allocbucket->ub_cnt:0,
3270 cache->uc_freebucket,
3271 cache->uc_freebucket?cache->uc_freebucket->ub_cnt:0);
3275 uma_print_keg(uma_keg_t keg)
3279 printf("keg: %s(%p) size %d(%d) flags %#x ipers %d ppera %d "
3280 "out %d free %d limit %d\n",
3281 keg->uk_name, keg, keg->uk_size, keg->uk_rsize, keg->uk_flags,
3282 keg->uk_ipers, keg->uk_ppera,
3283 (keg->uk_ipers * keg->uk_pages) - keg->uk_free, keg->uk_free,
3284 (keg->uk_maxpages / keg->uk_ppera) * keg->uk_ipers);
3285 printf("Part slabs:\n");
3286 LIST_FOREACH(slab, &keg->uk_part_slab, us_link)
3288 printf("Free slabs:\n");
3289 LIST_FOREACH(slab, &keg->uk_free_slab, us_link)
3291 printf("Full slabs:\n");
3292 LIST_FOREACH(slab, &keg->uk_full_slab, us_link)
3297 uma_print_zone(uma_zone_t zone)
3303 printf("zone: %s(%p) size %d flags %#x\n",
3304 zone->uz_name, zone, zone->uz_size, zone->uz_flags);
3305 LIST_FOREACH(kl, &zone->uz_kegs, kl_link)
3306 uma_print_keg(kl->kl_keg);
3308 cache = &zone->uz_cpu[i];
3309 printf("CPU %d Cache:\n", i);
3316 * Generate statistics across both the zone and its per-cpu cache's. Return
3317 * desired statistics if the pointer is non-NULL for that statistic.
3319 * Note: does not update the zone statistics, as it can't safely clear the
3320 * per-CPU cache statistic.
3322 * XXXRW: Following the uc_allocbucket and uc_freebucket pointers here isn't
3323 * safe from off-CPU; we should modify the caches to track this information
3324 * directly so that we don't have to.
3327 uma_zone_sumstat(uma_zone_t z, int *cachefreep, uint64_t *allocsp,
3328 uint64_t *freesp, uint64_t *sleepsp)
3331 uint64_t allocs, frees, sleeps;
3334 allocs = frees = sleeps = 0;
3337 cache = &z->uz_cpu[cpu];
3338 if (cache->uc_allocbucket != NULL)
3339 cachefree += cache->uc_allocbucket->ub_cnt;
3340 if (cache->uc_freebucket != NULL)
3341 cachefree += cache->uc_freebucket->ub_cnt;
3342 allocs += cache->uc_allocs;
3343 frees += cache->uc_frees;
3345 allocs += z->uz_allocs;
3346 frees += z->uz_frees;
3347 sleeps += z->uz_sleeps;
3348 if (cachefreep != NULL)
3349 *cachefreep = cachefree;
3350 if (allocsp != NULL)
3354 if (sleepsp != NULL)
3360 sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS)
3368 LIST_FOREACH(kz, &uma_kegs, uk_link) {
3369 LIST_FOREACH(z, &kz->uk_zones, uz_link)
3372 mtx_unlock(&uma_mtx);
3373 return (sysctl_handle_int(oidp, &count, 0, req));
3377 sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS)
3379 struct uma_stream_header ush;
3380 struct uma_type_header uth;
3381 struct uma_percpu_stat ups;
3382 uma_bucket_t bucket;
3389 int count, error, i;
3391 error = sysctl_wire_old_buffer(req, 0);
3394 sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
3398 LIST_FOREACH(kz, &uma_kegs, uk_link) {
3399 LIST_FOREACH(z, &kz->uk_zones, uz_link)
3404 * Insert stream header.
3406 bzero(&ush, sizeof(ush));
3407 ush.ush_version = UMA_STREAM_VERSION;
3408 ush.ush_maxcpus = (mp_maxid + 1);
3409 ush.ush_count = count;
3410 (void)sbuf_bcat(&sbuf, &ush, sizeof(ush));
3412 LIST_FOREACH(kz, &uma_kegs, uk_link) {
3413 LIST_FOREACH(z, &kz->uk_zones, uz_link) {
3414 bzero(&uth, sizeof(uth));
3416 strlcpy(uth.uth_name, z->uz_name, UTH_MAX_NAME);
3417 uth.uth_align = kz->uk_align;
3418 uth.uth_size = kz->uk_size;
3419 uth.uth_rsize = kz->uk_rsize;
3420 LIST_FOREACH(kl, &z->uz_kegs, kl_link) {
3422 uth.uth_maxpages += k->uk_maxpages;
3423 uth.uth_pages += k->uk_pages;
3424 uth.uth_keg_free += k->uk_free;
3425 uth.uth_limit = (k->uk_maxpages / k->uk_ppera)
3430 * A zone is secondary is it is not the first entry
3431 * on the keg's zone list.
3433 if ((z->uz_flags & UMA_ZONE_SECONDARY) &&
3434 (LIST_FIRST(&kz->uk_zones) != z))
3435 uth.uth_zone_flags = UTH_ZONE_SECONDARY;
3437 LIST_FOREACH(bucket, &z->uz_buckets, ub_link)
3438 uth.uth_zone_free += bucket->ub_cnt;
3439 uth.uth_allocs = z->uz_allocs;
3440 uth.uth_frees = z->uz_frees;
3441 uth.uth_fails = z->uz_fails;
3442 uth.uth_sleeps = z->uz_sleeps;
3443 (void)sbuf_bcat(&sbuf, &uth, sizeof(uth));
3445 * While it is not normally safe to access the cache
3446 * bucket pointers while not on the CPU that owns the
3447 * cache, we only allow the pointers to be exchanged
3448 * without the zone lock held, not invalidated, so
3449 * accept the possible race associated with bucket
3450 * exchange during monitoring.
3452 for (i = 0; i < (mp_maxid + 1); i++) {
3453 bzero(&ups, sizeof(ups));
3454 if (kz->uk_flags & UMA_ZFLAG_INTERNAL)
3458 cache = &z->uz_cpu[i];
3459 if (cache->uc_allocbucket != NULL)
3460 ups.ups_cache_free +=
3461 cache->uc_allocbucket->ub_cnt;
3462 if (cache->uc_freebucket != NULL)
3463 ups.ups_cache_free +=
3464 cache->uc_freebucket->ub_cnt;
3465 ups.ups_allocs = cache->uc_allocs;
3466 ups.ups_frees = cache->uc_frees;
3468 (void)sbuf_bcat(&sbuf, &ups, sizeof(ups));
3473 mtx_unlock(&uma_mtx);
3474 error = sbuf_finish(&sbuf);
3480 sysctl_handle_uma_zone_max(SYSCTL_HANDLER_ARGS)
3482 uma_zone_t zone = *(uma_zone_t *)arg1;
3483 int error, max, old;
3485 old = max = uma_zone_get_max(zone);
3486 error = sysctl_handle_int(oidp, &max, 0, req);
3487 if (error || !req->newptr)
3493 uma_zone_set_max(zone, max);
3499 sysctl_handle_uma_zone_cur(SYSCTL_HANDLER_ARGS)
3501 uma_zone_t zone = *(uma_zone_t *)arg1;
3504 cur = uma_zone_get_cur(zone);
3505 return (sysctl_handle_int(oidp, &cur, 0, req));
3509 DB_SHOW_COMMAND(uma, db_show_uma)
3511 uint64_t allocs, frees, sleeps;
3512 uma_bucket_t bucket;
3517 db_printf("%18s %8s %8s %8s %12s %8s %8s\n", "Zone", "Size", "Used",
3518 "Free", "Requests", "Sleeps", "Bucket");
3519 LIST_FOREACH(kz, &uma_kegs, uk_link) {
3520 LIST_FOREACH(z, &kz->uk_zones, uz_link) {
3521 if (kz->uk_flags & UMA_ZFLAG_INTERNAL) {
3522 allocs = z->uz_allocs;
3523 frees = z->uz_frees;
3524 sleeps = z->uz_sleeps;
3527 uma_zone_sumstat(z, &cachefree, &allocs,
3529 if (!((z->uz_flags & UMA_ZONE_SECONDARY) &&
3530 (LIST_FIRST(&kz->uk_zones) != z)))
3531 cachefree += kz->uk_free;
3532 LIST_FOREACH(bucket, &z->uz_buckets, ub_link)
3533 cachefree += bucket->ub_cnt;
3534 db_printf("%18s %8ju %8jd %8d %12ju %8ju %8u\n",
3535 z->uz_name, (uintmax_t)kz->uk_size,
3536 (intmax_t)(allocs - frees), cachefree,
3537 (uintmax_t)allocs, sleeps, z->uz_count);
3544 DB_SHOW_COMMAND(umacache, db_show_umacache)
3546 uint64_t allocs, frees;
3547 uma_bucket_t bucket;
3551 db_printf("%18s %8s %8s %8s %12s %8s\n", "Zone", "Size", "Used", "Free",
3552 "Requests", "Bucket");
3553 LIST_FOREACH(z, &uma_cachezones, uz_link) {
3554 uma_zone_sumstat(z, &cachefree, &allocs, &frees, NULL);
3555 LIST_FOREACH(bucket, &z->uz_buckets, ub_link)
3556 cachefree += bucket->ub_cnt;
3557 db_printf("%18s %8ju %8jd %8d %12ju %8u\n",
3558 z->uz_name, (uintmax_t)z->uz_size,
3559 (intmax_t)(allocs - frees), cachefree,
3560 (uintmax_t)allocs, z->uz_count);