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 TUNABLE_INT("vm.zone_warnings", &zone_warnings);
285 SYSCTL_INT(_vm, OID_AUTO, zone_warnings, CTLFLAG_RW, &zone_warnings, 0,
286 "Warn when UMA zones becomes full");
289 * This routine checks to see whether or not it's safe to enable buckets.
294 bucketdisable = vm_page_count_min();
298 * Initialize bucket_zones, the array of zones of buckets of various sizes.
300 * For each zone, calculate the memory required for each bucket, consisting
301 * of the header and an array of pointers.
306 struct uma_bucket_zone *ubz;
310 for (i = 0, ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++) {
311 size = roundup(sizeof(struct uma_bucket), sizeof(void *));
312 size += sizeof(void *) * ubz->ubz_entries;
313 ubz->ubz_zone = uma_zcreate(ubz->ubz_name, size,
314 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR,
315 UMA_ZONE_MTXCLASS | UMA_ZFLAG_BUCKET);
320 * Given a desired number of entries for a bucket, return the zone from which
321 * to allocate the bucket.
323 static struct uma_bucket_zone *
324 bucket_zone_lookup(int entries)
326 struct uma_bucket_zone *ubz;
328 for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++)
329 if (ubz->ubz_entries >= entries)
336 bucket_select(int size)
338 struct uma_bucket_zone *ubz;
340 ubz = &bucket_zones[0];
341 if (size > ubz->ubz_maxsize)
342 return MAX((ubz->ubz_maxsize * ubz->ubz_entries) / size, 1);
344 for (; ubz->ubz_entries != 0; ubz++)
345 if (ubz->ubz_maxsize < size)
348 return (ubz->ubz_entries);
352 bucket_alloc(uma_zone_t zone, void *udata, int flags)
354 struct uma_bucket_zone *ubz;
358 * This is to stop us from allocating per cpu buckets while we're
359 * running out of vm.boot_pages. Otherwise, we would exhaust the
360 * boot pages. This also prevents us from allocating buckets in
361 * low memory situations.
366 * To limit bucket recursion we store the original zone flags
367 * in a cookie passed via zalloc_arg/zfree_arg. This allows the
368 * NOVM flag to persist even through deep recursions. We also
369 * store ZFLAG_BUCKET once we have recursed attempting to allocate
370 * a bucket for a bucket zone so we do not allow infinite bucket
371 * recursion. This cookie will even persist to frees of unused
372 * buckets via the allocation path or bucket allocations in the
375 if ((zone->uz_flags & UMA_ZFLAG_BUCKET) == 0)
376 udata = (void *)(uintptr_t)zone->uz_flags;
378 if ((uintptr_t)udata & UMA_ZFLAG_BUCKET)
380 udata = (void *)((uintptr_t)udata | UMA_ZFLAG_BUCKET);
382 if ((uintptr_t)udata & UMA_ZFLAG_CACHEONLY)
384 ubz = bucket_zone_lookup(zone->uz_count);
385 if (ubz->ubz_zone == zone && (ubz + 1)->ubz_entries != 0)
387 bucket = uma_zalloc_arg(ubz->ubz_zone, udata, flags);
390 bzero(bucket->ub_bucket, sizeof(void *) * ubz->ubz_entries);
393 bucket->ub_entries = ubz->ubz_entries;
400 bucket_free(uma_zone_t zone, uma_bucket_t bucket, void *udata)
402 struct uma_bucket_zone *ubz;
404 KASSERT(bucket->ub_cnt == 0,
405 ("bucket_free: Freeing a non free bucket."));
406 if ((zone->uz_flags & UMA_ZFLAG_BUCKET) == 0)
407 udata = (void *)(uintptr_t)zone->uz_flags;
408 ubz = bucket_zone_lookup(bucket->ub_entries);
409 uma_zfree_arg(ubz->ubz_zone, bucket, udata);
413 bucket_zone_drain(void)
415 struct uma_bucket_zone *ubz;
417 for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++)
418 zone_drain(ubz->ubz_zone);
422 zone_log_warning(uma_zone_t zone)
424 static const struct timeval warninterval = { 300, 0 };
426 if (!zone_warnings || zone->uz_warning == NULL)
429 if (ratecheck(&zone->uz_ratecheck, &warninterval))
430 printf("[zone: %s] %s\n", zone->uz_name, zone->uz_warning);
434 zone_foreach_keg(uma_zone_t zone, void (*kegfn)(uma_keg_t))
438 LIST_FOREACH(klink, &zone->uz_kegs, kl_link)
439 kegfn(klink->kl_keg);
443 * Routine called by timeout which is used to fire off some time interval
444 * based calculations. (stats, hash size, etc.)
453 uma_timeout(void *unused)
456 zone_foreach(zone_timeout);
458 /* Reschedule this event */
459 callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL);
463 * Routine to perform timeout driven calculations. This expands the
464 * hashes and does per cpu statistics aggregation.
469 keg_timeout(uma_keg_t keg)
474 * Expand the keg hash table.
476 * This is done if the number of slabs is larger than the hash size.
477 * What I'm trying to do here is completely reduce collisions. This
478 * may be a little aggressive. Should I allow for two collisions max?
480 if (keg->uk_flags & UMA_ZONE_HASH &&
481 keg->uk_pages / keg->uk_ppera >= keg->uk_hash.uh_hashsize) {
482 struct uma_hash newhash;
483 struct uma_hash oldhash;
487 * This is so involved because allocating and freeing
488 * while the keg lock is held will lead to deadlock.
489 * I have to do everything in stages and check for
492 newhash = keg->uk_hash;
494 ret = hash_alloc(&newhash);
497 if (hash_expand(&keg->uk_hash, &newhash)) {
498 oldhash = keg->uk_hash;
499 keg->uk_hash = newhash;
512 zone_timeout(uma_zone_t zone)
515 zone_foreach_keg(zone, &keg_timeout);
519 * Allocate and zero fill the next sized hash table from the appropriate
523 * hash A new hash structure with the old hash size in uh_hashsize
526 * 1 on sucess and 0 on failure.
529 hash_alloc(struct uma_hash *hash)
534 oldsize = hash->uh_hashsize;
536 /* We're just going to go to a power of two greater */
538 hash->uh_hashsize = oldsize * 2;
539 alloc = sizeof(hash->uh_slab_hash[0]) * hash->uh_hashsize;
540 hash->uh_slab_hash = (struct slabhead *)malloc(alloc,
541 M_UMAHASH, M_NOWAIT);
543 alloc = sizeof(hash->uh_slab_hash[0]) * UMA_HASH_SIZE_INIT;
544 hash->uh_slab_hash = zone_alloc_item(hashzone, NULL,
546 hash->uh_hashsize = UMA_HASH_SIZE_INIT;
548 if (hash->uh_slab_hash) {
549 bzero(hash->uh_slab_hash, alloc);
550 hash->uh_hashmask = hash->uh_hashsize - 1;
558 * Expands the hash table for HASH zones. This is done from zone_timeout
559 * to reduce collisions. This must not be done in the regular allocation
560 * path, otherwise, we can recurse on the vm while allocating pages.
563 * oldhash The hash you want to expand
564 * newhash The hash structure for the new table
572 hash_expand(struct uma_hash *oldhash, struct uma_hash *newhash)
578 if (!newhash->uh_slab_hash)
581 if (oldhash->uh_hashsize >= newhash->uh_hashsize)
585 * I need to investigate hash algorithms for resizing without a
589 for (i = 0; i < oldhash->uh_hashsize; i++)
590 while (!SLIST_EMPTY(&oldhash->uh_slab_hash[i])) {
591 slab = SLIST_FIRST(&oldhash->uh_slab_hash[i]);
592 SLIST_REMOVE_HEAD(&oldhash->uh_slab_hash[i], us_hlink);
593 hval = UMA_HASH(newhash, slab->us_data);
594 SLIST_INSERT_HEAD(&newhash->uh_slab_hash[hval],
602 * Free the hash bucket to the appropriate backing store.
605 * slab_hash The hash bucket we're freeing
606 * hashsize The number of entries in that hash bucket
612 hash_free(struct uma_hash *hash)
614 if (hash->uh_slab_hash == NULL)
616 if (hash->uh_hashsize == UMA_HASH_SIZE_INIT)
617 zone_free_item(hashzone, hash->uh_slab_hash, NULL, SKIP_NONE);
619 free(hash->uh_slab_hash, M_UMAHASH);
623 * Frees all outstanding items in a bucket
626 * zone The zone to free to, must be unlocked.
627 * bucket The free/alloc bucket with items, cpu queue must be locked.
634 bucket_drain(uma_zone_t zone, uma_bucket_t bucket)
642 for (i = 0; i < bucket->ub_cnt; i++)
643 zone->uz_fini(bucket->ub_bucket[i], zone->uz_size);
644 zone->uz_release(zone->uz_arg, bucket->ub_bucket, bucket->ub_cnt);
649 * Drains the per cpu caches for a zone.
651 * NOTE: This may only be called while the zone is being turn down, and not
652 * during normal operation. This is necessary in order that we do not have
653 * to migrate CPUs to drain the per-CPU caches.
656 * zone The zone to drain, must be unlocked.
662 cache_drain(uma_zone_t zone)
668 * XXX: It is safe to not lock the per-CPU caches, because we're
669 * tearing down the zone anyway. I.e., there will be no further use
670 * of the caches at this point.
672 * XXX: It would good to be able to assert that the zone is being
673 * torn down to prevent improper use of cache_drain().
675 * XXX: We lock the zone before passing into bucket_cache_drain() as
676 * it is used elsewhere. Should the tear-down path be made special
677 * there in some form?
680 cache = &zone->uz_cpu[cpu];
681 bucket_drain(zone, cache->uc_allocbucket);
682 bucket_drain(zone, cache->uc_freebucket);
683 if (cache->uc_allocbucket != NULL)
684 bucket_free(zone, cache->uc_allocbucket, NULL);
685 if (cache->uc_freebucket != NULL)
686 bucket_free(zone, cache->uc_freebucket, NULL);
687 cache->uc_allocbucket = cache->uc_freebucket = NULL;
690 bucket_cache_drain(zone);
695 cache_shrink(uma_zone_t zone)
698 if (zone->uz_flags & UMA_ZFLAG_INTERNAL)
702 zone->uz_count = (zone->uz_count_min + zone->uz_count) / 2;
707 cache_drain_safe_cpu(uma_zone_t zone)
712 if (zone->uz_flags & UMA_ZFLAG_INTERNAL)
718 cache = &zone->uz_cpu[curcpu];
719 if (cache->uc_allocbucket) {
720 if (cache->uc_allocbucket->ub_cnt != 0)
721 LIST_INSERT_HEAD(&zone->uz_buckets,
722 cache->uc_allocbucket, ub_link);
724 b1 = cache->uc_allocbucket;
725 cache->uc_allocbucket = NULL;
727 if (cache->uc_freebucket) {
728 if (cache->uc_freebucket->ub_cnt != 0)
729 LIST_INSERT_HEAD(&zone->uz_buckets,
730 cache->uc_freebucket, ub_link);
732 b2 = cache->uc_freebucket;
733 cache->uc_freebucket = NULL;
738 bucket_free(zone, b1, NULL);
740 bucket_free(zone, b2, NULL);
744 * Safely drain per-CPU caches of a zone(s) to alloc bucket.
745 * This is an expensive call because it needs to bind to all CPUs
746 * one by one and enter a critical section on each of them in order
747 * to safely access their cache buckets.
748 * Zone lock must not be held on call this function.
751 cache_drain_safe(uma_zone_t zone)
756 * Polite bucket sizes shrinking was not enouth, shrink aggressively.
761 zone_foreach(cache_shrink);
764 thread_lock(curthread);
765 sched_bind(curthread, cpu);
766 thread_unlock(curthread);
769 cache_drain_safe_cpu(zone);
771 zone_foreach(cache_drain_safe_cpu);
773 thread_lock(curthread);
774 sched_unbind(curthread);
775 thread_unlock(curthread);
779 * Drain the cached buckets from a zone. Expects a locked zone on entry.
782 bucket_cache_drain(uma_zone_t zone)
787 * Drain the bucket queues and free the buckets, we just keep two per
790 while ((bucket = LIST_FIRST(&zone->uz_buckets)) != NULL) {
791 LIST_REMOVE(bucket, ub_link);
793 bucket_drain(zone, bucket);
794 bucket_free(zone, bucket, NULL);
799 * Shrink further bucket sizes. Price of single zone lock collision
800 * is probably lower then price of global cache drain.
802 if (zone->uz_count > zone->uz_count_min)
807 keg_free_slab(uma_keg_t keg, uma_slab_t slab, int start)
814 flags = slab->us_flags;
816 if (keg->uk_fini != NULL) {
817 for (i--; i > -1; i--)
818 keg->uk_fini(slab->us_data + (keg->uk_rsize * i),
821 if (keg->uk_flags & UMA_ZONE_OFFPAGE)
822 zone_free_item(keg->uk_slabzone, slab, NULL, SKIP_NONE);
824 printf("%s: Returning %d bytes.\n", keg->uk_name,
825 PAGE_SIZE * keg->uk_ppera);
827 keg->uk_freef(mem, PAGE_SIZE * keg->uk_ppera, flags);
831 * Frees pages from a keg back to the system. This is done on demand from
832 * the pageout daemon.
837 keg_drain(uma_keg_t keg)
839 struct slabhead freeslabs = { 0 };
844 * We don't want to take pages from statically allocated kegs at this
847 if (keg->uk_flags & UMA_ZONE_NOFREE || keg->uk_freef == NULL)
851 printf("%s free items: %u\n", keg->uk_name, keg->uk_free);
854 if (keg->uk_free == 0)
857 slab = LIST_FIRST(&keg->uk_free_slab);
859 n = LIST_NEXT(slab, us_link);
861 /* We have no where to free these to */
862 if (slab->us_flags & UMA_SLAB_BOOT) {
867 LIST_REMOVE(slab, us_link);
868 keg->uk_pages -= keg->uk_ppera;
869 keg->uk_free -= keg->uk_ipers;
871 if (keg->uk_flags & UMA_ZONE_HASH)
872 UMA_HASH_REMOVE(&keg->uk_hash, slab, slab->us_data);
874 SLIST_INSERT_HEAD(&freeslabs, slab, us_hlink);
881 while ((slab = SLIST_FIRST(&freeslabs)) != NULL) {
882 SLIST_REMOVE(&freeslabs, slab, uma_slab, us_hlink);
883 keg_free_slab(keg, slab, keg->uk_ipers);
888 zone_drain_wait(uma_zone_t zone, int waitok)
892 * Set draining to interlock with zone_dtor() so we can release our
893 * locks as we go. Only dtor() should do a WAITOK call since it
894 * is the only call that knows the structure will still be available
898 while (zone->uz_flags & UMA_ZFLAG_DRAINING) {
899 if (waitok == M_NOWAIT)
901 mtx_unlock(&uma_mtx);
902 msleep(zone, zone->uz_lockptr, PVM, "zonedrain", 1);
905 zone->uz_flags |= UMA_ZFLAG_DRAINING;
906 bucket_cache_drain(zone);
909 * The DRAINING flag protects us from being freed while
910 * we're running. Normally the uma_mtx would protect us but we
911 * must be able to release and acquire the right lock for each keg.
913 zone_foreach_keg(zone, &keg_drain);
915 zone->uz_flags &= ~UMA_ZFLAG_DRAINING;
922 zone_drain(uma_zone_t zone)
925 zone_drain_wait(zone, M_NOWAIT);
929 * Allocate a new slab for a keg. This does not insert the slab onto a list.
932 * wait Shall we wait?
935 * The slab that was allocated or NULL if there is no memory and the
936 * caller specified M_NOWAIT.
939 keg_alloc_slab(uma_keg_t keg, uma_zone_t zone, int wait)
941 uma_slabrefcnt_t slabref;
948 mtx_assert(&keg->uk_lock, MA_OWNED);
953 printf("alloc_slab: Allocating a new slab for %s\n", keg->uk_name);
955 allocf = keg->uk_allocf;
958 if (keg->uk_flags & UMA_ZONE_OFFPAGE) {
959 slab = zone_alloc_item(keg->uk_slabzone, NULL, wait);
965 * This reproduces the old vm_zone behavior of zero filling pages the
966 * first time they are added to a zone.
968 * Malloced items are zeroed in uma_zalloc.
971 if ((keg->uk_flags & UMA_ZONE_MALLOC) == 0)
976 if (keg->uk_flags & UMA_ZONE_NODUMP)
979 /* zone is passed for legacy reasons. */
980 mem = allocf(zone, keg->uk_ppera * PAGE_SIZE, &flags, wait);
982 if (keg->uk_flags & UMA_ZONE_OFFPAGE)
983 zone_free_item(keg->uk_slabzone, slab, NULL, SKIP_NONE);
988 /* Point the slab into the allocated memory */
989 if (!(keg->uk_flags & UMA_ZONE_OFFPAGE))
990 slab = (uma_slab_t )(mem + keg->uk_pgoff);
992 if (keg->uk_flags & UMA_ZONE_VTOSLAB)
993 for (i = 0; i < keg->uk_ppera; i++)
994 vsetslab((vm_offset_t)mem + (i * PAGE_SIZE), slab);
998 slab->us_freecount = keg->uk_ipers;
999 slab->us_flags = flags;
1000 BIT_FILL(SLAB_SETSIZE, &slab->us_free);
1002 BIT_ZERO(SLAB_SETSIZE, &slab->us_debugfree);
1004 if (keg->uk_flags & UMA_ZONE_REFCNT) {
1005 slabref = (uma_slabrefcnt_t)slab;
1006 for (i = 0; i < keg->uk_ipers; i++)
1007 slabref->us_refcnt[i] = 0;
1010 if (keg->uk_init != NULL) {
1011 for (i = 0; i < keg->uk_ipers; i++)
1012 if (keg->uk_init(slab->us_data + (keg->uk_rsize * i),
1013 keg->uk_size, wait) != 0)
1015 if (i != keg->uk_ipers) {
1016 keg_free_slab(keg, slab, i);
1025 if (keg->uk_flags & UMA_ZONE_HASH)
1026 UMA_HASH_INSERT(&keg->uk_hash, slab, mem);
1028 keg->uk_pages += keg->uk_ppera;
1029 keg->uk_free += keg->uk_ipers;
1036 * This function is intended to be used early on in place of page_alloc() so
1037 * that we may use the boot time page cache to satisfy allocations before
1041 startup_alloc(uma_zone_t zone, int bytes, uint8_t *pflag, int wait)
1045 int pages, check_pages;
1047 keg = zone_first_keg(zone);
1048 pages = howmany(bytes, PAGE_SIZE);
1049 check_pages = pages - 1;
1050 KASSERT(pages > 0, ("startup_alloc can't reserve 0 pages\n"));
1053 * Check our small startup cache to see if it has pages remaining.
1055 mtx_lock(&uma_boot_pages_mtx);
1057 /* First check if we have enough room. */
1058 tmps = LIST_FIRST(&uma_boot_pages);
1059 while (tmps != NULL && check_pages-- > 0)
1060 tmps = LIST_NEXT(tmps, us_link);
1063 * It's ok to lose tmps references. The last one will
1064 * have tmps->us_data pointing to the start address of
1065 * "pages" contiguous pages of memory.
1067 while (pages-- > 0) {
1068 tmps = LIST_FIRST(&uma_boot_pages);
1069 LIST_REMOVE(tmps, us_link);
1071 mtx_unlock(&uma_boot_pages_mtx);
1072 *pflag = tmps->us_flags;
1073 return (tmps->us_data);
1075 mtx_unlock(&uma_boot_pages_mtx);
1076 if (booted < UMA_STARTUP2)
1077 panic("UMA: Increase vm.boot_pages");
1079 * Now that we've booted reset these users to their real allocator.
1081 #ifdef UMA_MD_SMALL_ALLOC
1082 keg->uk_allocf = (keg->uk_ppera > 1) ? page_alloc : uma_small_alloc;
1084 keg->uk_allocf = page_alloc;
1086 return keg->uk_allocf(zone, bytes, pflag, wait);
1090 * Allocates a number of pages from the system
1093 * bytes The number of bytes requested
1094 * wait Shall we wait?
1097 * A pointer to the alloced memory or possibly
1098 * NULL if M_NOWAIT is set.
1101 page_alloc(uma_zone_t zone, int bytes, uint8_t *pflag, int wait)
1103 void *p; /* Returned page */
1105 *pflag = UMA_SLAB_KMEM;
1106 p = (void *) kmem_malloc(kmem_arena, bytes, wait);
1112 * Allocates a number of pages from within an object
1115 * bytes The number of bytes requested
1116 * wait Shall we wait?
1119 * A pointer to the alloced memory or possibly
1120 * NULL if M_NOWAIT is set.
1123 noobj_alloc(uma_zone_t zone, int bytes, uint8_t *flags, int wait)
1125 TAILQ_HEAD(, vm_page) alloctail;
1127 vm_offset_t retkva, zkva;
1128 vm_page_t p, p_next;
1131 TAILQ_INIT(&alloctail);
1132 keg = zone_first_keg(zone);
1134 npages = howmany(bytes, PAGE_SIZE);
1135 while (npages > 0) {
1136 p = vm_page_alloc(NULL, 0, VM_ALLOC_INTERRUPT |
1137 VM_ALLOC_WIRED | VM_ALLOC_NOOBJ);
1140 * Since the page does not belong to an object, its
1143 TAILQ_INSERT_TAIL(&alloctail, p, listq);
1147 if (wait & M_WAITOK) {
1153 * Page allocation failed, free intermediate pages and
1156 TAILQ_FOREACH_SAFE(p, &alloctail, listq, p_next) {
1157 vm_page_unwire(p, 0);
1162 *flags = UMA_SLAB_PRIV;
1163 zkva = keg->uk_kva +
1164 atomic_fetchadd_long(&keg->uk_offset, round_page(bytes));
1166 TAILQ_FOREACH(p, &alloctail, listq) {
1167 pmap_qenter(zkva, &p, 1);
1171 return ((void *)retkva);
1175 * Frees a number of pages to the system
1178 * mem A pointer to the memory to be freed
1179 * size The size of the memory being freed
1180 * flags The original p->us_flags field
1186 page_free(void *mem, int size, uint8_t flags)
1190 if (flags & UMA_SLAB_KMEM)
1192 else if (flags & UMA_SLAB_KERNEL)
1193 vmem = kernel_arena;
1195 panic("UMA: page_free used with invalid flags %d", flags);
1197 kmem_free(vmem, (vm_offset_t)mem, size);
1201 * Zero fill initializer
1203 * Arguments/Returns follow uma_init specifications
1206 zero_init(void *mem, int size, int flags)
1213 * Finish creating a small uma keg. This calculates ipers, and the keg size.
1216 * keg The zone we should initialize
1222 keg_small_init(uma_keg_t keg)
1229 if (keg->uk_flags & UMA_ZONE_PCPU) {
1230 u_int ncpus = mp_ncpus ? mp_ncpus : MAXCPU;
1232 keg->uk_slabsize = sizeof(struct pcpu);
1233 keg->uk_ppera = howmany(ncpus * sizeof(struct pcpu),
1236 keg->uk_slabsize = UMA_SLAB_SIZE;
1241 * Calculate the size of each allocation (rsize) according to
1242 * alignment. If the requested size is smaller than we have
1243 * allocation bits for we round it up.
1245 rsize = keg->uk_size;
1246 if (rsize < keg->uk_slabsize / SLAB_SETSIZE)
1247 rsize = keg->uk_slabsize / SLAB_SETSIZE;
1248 if (rsize & keg->uk_align)
1249 rsize = (rsize & ~keg->uk_align) + (keg->uk_align + 1);
1250 keg->uk_rsize = rsize;
1252 KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0 ||
1253 keg->uk_rsize < sizeof(struct pcpu),
1254 ("%s: size %u too large", __func__, keg->uk_rsize));
1256 if (keg->uk_flags & UMA_ZONE_REFCNT)
1257 rsize += sizeof(uint32_t);
1259 if (keg->uk_flags & UMA_ZONE_OFFPAGE)
1262 shsize = sizeof(struct uma_slab);
1264 keg->uk_ipers = (keg->uk_slabsize - shsize) / rsize;
1265 KASSERT(keg->uk_ipers > 0 && keg->uk_ipers <= SLAB_SETSIZE,
1266 ("%s: keg->uk_ipers %u", __func__, keg->uk_ipers));
1268 memused = keg->uk_ipers * rsize + shsize;
1269 wastedspace = keg->uk_slabsize - memused;
1272 * We can't do OFFPAGE if we're internal or if we've been
1273 * asked to not go to the VM for buckets. If we do this we
1274 * may end up going to the VM for slabs which we do not
1275 * want to do if we're UMA_ZFLAG_CACHEONLY as a result
1276 * of UMA_ZONE_VM, which clearly forbids it.
1278 if ((keg->uk_flags & UMA_ZFLAG_INTERNAL) ||
1279 (keg->uk_flags & UMA_ZFLAG_CACHEONLY))
1283 * See if using an OFFPAGE slab will limit our waste. Only do
1284 * this if it permits more items per-slab.
1286 * XXX We could try growing slabsize to limit max waste as well.
1287 * Historically this was not done because the VM could not
1288 * efficiently handle contiguous allocations.
1290 if ((wastedspace >= keg->uk_slabsize / UMA_MAX_WASTE) &&
1291 (keg->uk_ipers < (keg->uk_slabsize / keg->uk_rsize))) {
1292 keg->uk_ipers = keg->uk_slabsize / keg->uk_rsize;
1293 KASSERT(keg->uk_ipers > 0 && keg->uk_ipers <= SLAB_SETSIZE,
1294 ("%s: keg->uk_ipers %u", __func__, keg->uk_ipers));
1296 printf("UMA decided we need offpage slab headers for "
1297 "keg: %s, calculated wastedspace = %d, "
1298 "maximum wasted space allowed = %d, "
1299 "calculated ipers = %d, "
1300 "new wasted space = %d\n", keg->uk_name, wastedspace,
1301 keg->uk_slabsize / UMA_MAX_WASTE, keg->uk_ipers,
1302 keg->uk_slabsize - keg->uk_ipers * keg->uk_rsize);
1304 keg->uk_flags |= UMA_ZONE_OFFPAGE;
1307 if ((keg->uk_flags & UMA_ZONE_OFFPAGE) &&
1308 (keg->uk_flags & UMA_ZONE_VTOSLAB) == 0)
1309 keg->uk_flags |= UMA_ZONE_HASH;
1313 * Finish creating a large (> UMA_SLAB_SIZE) uma kegs. Just give in and do
1314 * OFFPAGE for now. When I can allow for more dynamic slab sizes this will be
1318 * keg The keg we should initialize
1324 keg_large_init(uma_keg_t keg)
1328 KASSERT(keg != NULL, ("Keg is null in keg_large_init"));
1329 KASSERT((keg->uk_flags & UMA_ZFLAG_CACHEONLY) == 0,
1330 ("keg_large_init: Cannot large-init a UMA_ZFLAG_CACHEONLY keg"));
1331 KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0,
1332 ("%s: Cannot large-init a UMA_ZONE_PCPU keg", __func__));
1334 keg->uk_ppera = howmany(keg->uk_size, PAGE_SIZE);
1335 keg->uk_slabsize = keg->uk_ppera * PAGE_SIZE;
1337 keg->uk_rsize = keg->uk_size;
1339 /* We can't do OFFPAGE if we're internal, bail out here. */
1340 if (keg->uk_flags & UMA_ZFLAG_INTERNAL)
1343 /* Check whether we have enough space to not do OFFPAGE. */
1344 if ((keg->uk_flags & UMA_ZONE_OFFPAGE) == 0) {
1345 shsize = sizeof(struct uma_slab);
1346 if (keg->uk_flags & UMA_ZONE_REFCNT)
1347 shsize += keg->uk_ipers * sizeof(uint32_t);
1348 if (shsize & UMA_ALIGN_PTR)
1349 shsize = (shsize & ~UMA_ALIGN_PTR) +
1350 (UMA_ALIGN_PTR + 1);
1352 if ((PAGE_SIZE * keg->uk_ppera) - keg->uk_rsize < shsize)
1353 keg->uk_flags |= UMA_ZONE_OFFPAGE;
1356 if ((keg->uk_flags & UMA_ZONE_OFFPAGE) &&
1357 (keg->uk_flags & UMA_ZONE_VTOSLAB) == 0)
1358 keg->uk_flags |= UMA_ZONE_HASH;
1362 keg_cachespread_init(uma_keg_t keg)
1369 KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0,
1370 ("%s: Cannot cachespread-init a UMA_ZONE_PCPU keg", __func__));
1372 alignsize = keg->uk_align + 1;
1373 rsize = keg->uk_size;
1375 * We want one item to start on every align boundary in a page. To
1376 * do this we will span pages. We will also extend the item by the
1377 * size of align if it is an even multiple of align. Otherwise, it
1378 * would fall on the same boundary every time.
1380 if (rsize & keg->uk_align)
1381 rsize = (rsize & ~keg->uk_align) + alignsize;
1382 if ((rsize & alignsize) == 0)
1384 trailer = rsize - keg->uk_size;
1385 pages = (rsize * (PAGE_SIZE / alignsize)) / PAGE_SIZE;
1386 pages = MIN(pages, (128 * 1024) / PAGE_SIZE);
1387 keg->uk_rsize = rsize;
1388 keg->uk_ppera = pages;
1389 keg->uk_slabsize = UMA_SLAB_SIZE;
1390 keg->uk_ipers = ((pages * PAGE_SIZE) + trailer) / rsize;
1391 keg->uk_flags |= UMA_ZONE_OFFPAGE | UMA_ZONE_VTOSLAB;
1392 KASSERT(keg->uk_ipers <= SLAB_SETSIZE,
1393 ("%s: keg->uk_ipers too high(%d) increase max_ipers", __func__,
1398 * Keg header ctor. This initializes all fields, locks, etc. And inserts
1399 * the keg onto the global keg list.
1401 * Arguments/Returns follow uma_ctor specifications
1402 * udata Actually uma_kctor_args
1405 keg_ctor(void *mem, int size, void *udata, int flags)
1407 struct uma_kctor_args *arg = udata;
1408 uma_keg_t keg = mem;
1412 keg->uk_size = arg->size;
1413 keg->uk_init = arg->uminit;
1414 keg->uk_fini = arg->fini;
1415 keg->uk_align = arg->align;
1417 keg->uk_reserve = 0;
1419 keg->uk_flags = arg->flags;
1420 keg->uk_allocf = page_alloc;
1421 keg->uk_freef = page_free;
1422 keg->uk_slabzone = NULL;
1425 * The master zone is passed to us at keg-creation time.
1428 keg->uk_name = zone->uz_name;
1430 if (arg->flags & UMA_ZONE_VM)
1431 keg->uk_flags |= UMA_ZFLAG_CACHEONLY;
1433 if (arg->flags & UMA_ZONE_ZINIT)
1434 keg->uk_init = zero_init;
1436 if (arg->flags & UMA_ZONE_REFCNT || arg->flags & UMA_ZONE_MALLOC)
1437 keg->uk_flags |= UMA_ZONE_VTOSLAB;
1439 if (arg->flags & UMA_ZONE_PCPU)
1441 keg->uk_flags |= UMA_ZONE_OFFPAGE;
1443 keg->uk_flags &= ~UMA_ZONE_PCPU;
1446 if (keg->uk_flags & UMA_ZONE_CACHESPREAD) {
1447 keg_cachespread_init(keg);
1448 } else if (keg->uk_flags & UMA_ZONE_REFCNT) {
1450 (UMA_SLAB_SIZE - sizeof(struct uma_slab_refcnt) -
1452 keg_large_init(keg);
1454 keg_small_init(keg);
1456 if (keg->uk_size > (UMA_SLAB_SIZE - sizeof(struct uma_slab)))
1457 keg_large_init(keg);
1459 keg_small_init(keg);
1462 if (keg->uk_flags & UMA_ZONE_OFFPAGE) {
1463 if (keg->uk_flags & UMA_ZONE_REFCNT) {
1464 if (keg->uk_ipers > uma_max_ipers_ref)
1465 panic("Too many ref items per zone: %d > %d\n",
1466 keg->uk_ipers, uma_max_ipers_ref);
1467 keg->uk_slabzone = slabrefzone;
1469 keg->uk_slabzone = slabzone;
1473 * If we haven't booted yet we need allocations to go through the
1474 * startup cache until the vm is ready.
1476 if (keg->uk_ppera == 1) {
1477 #ifdef UMA_MD_SMALL_ALLOC
1478 keg->uk_allocf = uma_small_alloc;
1479 keg->uk_freef = uma_small_free;
1481 if (booted < UMA_STARTUP)
1482 keg->uk_allocf = startup_alloc;
1484 if (booted < UMA_STARTUP2)
1485 keg->uk_allocf = startup_alloc;
1487 } else if (booted < UMA_STARTUP2 &&
1488 (keg->uk_flags & UMA_ZFLAG_INTERNAL))
1489 keg->uk_allocf = startup_alloc;
1492 * Initialize keg's lock
1494 KEG_LOCK_INIT(keg, (arg->flags & UMA_ZONE_MTXCLASS));
1497 * If we're putting the slab header in the actual page we need to
1498 * figure out where in each page it goes. This calculates a right
1499 * justified offset into the memory on an ALIGN_PTR boundary.
1501 if (!(keg->uk_flags & UMA_ZONE_OFFPAGE)) {
1504 /* Size of the slab struct and free list */
1505 totsize = sizeof(struct uma_slab);
1507 /* Size of the reference counts. */
1508 if (keg->uk_flags & UMA_ZONE_REFCNT)
1509 totsize += keg->uk_ipers * sizeof(uint32_t);
1511 if (totsize & UMA_ALIGN_PTR)
1512 totsize = (totsize & ~UMA_ALIGN_PTR) +
1513 (UMA_ALIGN_PTR + 1);
1514 keg->uk_pgoff = (PAGE_SIZE * keg->uk_ppera) - totsize;
1517 * The only way the following is possible is if with our
1518 * UMA_ALIGN_PTR adjustments we are now bigger than
1519 * UMA_SLAB_SIZE. I haven't checked whether this is
1520 * mathematically possible for all cases, so we make
1523 totsize = keg->uk_pgoff + sizeof(struct uma_slab);
1524 if (keg->uk_flags & UMA_ZONE_REFCNT)
1525 totsize += keg->uk_ipers * sizeof(uint32_t);
1526 if (totsize > PAGE_SIZE * keg->uk_ppera) {
1527 printf("zone %s ipers %d rsize %d size %d\n",
1528 zone->uz_name, keg->uk_ipers, keg->uk_rsize,
1530 panic("UMA slab won't fit.");
1534 if (keg->uk_flags & UMA_ZONE_HASH)
1535 hash_alloc(&keg->uk_hash);
1538 printf("UMA: %s(%p) size %d(%d) flags %#x ipers %d ppera %d out %d free %d\n",
1539 zone->uz_name, zone, keg->uk_size, keg->uk_rsize, keg->uk_flags,
1540 keg->uk_ipers, keg->uk_ppera,
1541 (keg->uk_ipers * keg->uk_pages) - keg->uk_free, keg->uk_free);
1544 LIST_INSERT_HEAD(&keg->uk_zones, zone, uz_link);
1547 LIST_INSERT_HEAD(&uma_kegs, keg, uk_link);
1548 mtx_unlock(&uma_mtx);
1553 * Zone header ctor. This initializes all fields, locks, etc.
1555 * Arguments/Returns follow uma_ctor specifications
1556 * udata Actually uma_zctor_args
1559 zone_ctor(void *mem, int size, void *udata, int flags)
1561 struct uma_zctor_args *arg = udata;
1562 uma_zone_t zone = mem;
1567 zone->uz_name = arg->name;
1568 zone->uz_ctor = arg->ctor;
1569 zone->uz_dtor = arg->dtor;
1570 zone->uz_slab = zone_fetch_slab;
1571 zone->uz_init = NULL;
1572 zone->uz_fini = NULL;
1573 zone->uz_allocs = 0;
1576 zone->uz_sleeps = 0;
1578 zone->uz_count_min = 0;
1580 zone->uz_warning = NULL;
1581 timevalclear(&zone->uz_ratecheck);
1584 ZONE_LOCK_INIT(zone, (arg->flags & UMA_ZONE_MTXCLASS));
1587 * This is a pure cache zone, no kegs.
1590 if (arg->flags & UMA_ZONE_VM)
1591 arg->flags |= UMA_ZFLAG_CACHEONLY;
1592 zone->uz_flags = arg->flags;
1593 zone->uz_size = arg->size;
1594 zone->uz_import = arg->import;
1595 zone->uz_release = arg->release;
1596 zone->uz_arg = arg->arg;
1597 zone->uz_lockptr = &zone->uz_lock;
1599 LIST_INSERT_HEAD(&uma_cachezones, zone, uz_link);
1600 mtx_unlock(&uma_mtx);
1605 * Use the regular zone/keg/slab allocator.
1607 zone->uz_import = (uma_import)zone_import;
1608 zone->uz_release = (uma_release)zone_release;
1609 zone->uz_arg = zone;
1611 if (arg->flags & UMA_ZONE_SECONDARY) {
1612 KASSERT(arg->keg != NULL, ("Secondary zone on zero'd keg"));
1613 zone->uz_init = arg->uminit;
1614 zone->uz_fini = arg->fini;
1615 zone->uz_lockptr = &keg->uk_lock;
1616 zone->uz_flags |= UMA_ZONE_SECONDARY;
1619 LIST_FOREACH(z, &keg->uk_zones, uz_link) {
1620 if (LIST_NEXT(z, uz_link) == NULL) {
1621 LIST_INSERT_AFTER(z, zone, uz_link);
1626 mtx_unlock(&uma_mtx);
1627 } else if (keg == NULL) {
1628 if ((keg = uma_kcreate(zone, arg->size, arg->uminit, arg->fini,
1629 arg->align, arg->flags)) == NULL)
1632 struct uma_kctor_args karg;
1635 /* We should only be here from uma_startup() */
1636 karg.size = arg->size;
1637 karg.uminit = arg->uminit;
1638 karg.fini = arg->fini;
1639 karg.align = arg->align;
1640 karg.flags = arg->flags;
1642 error = keg_ctor(arg->keg, sizeof(struct uma_keg), &karg,
1649 * Link in the first keg.
1651 zone->uz_klink.kl_keg = keg;
1652 LIST_INSERT_HEAD(&zone->uz_kegs, &zone->uz_klink, kl_link);
1653 zone->uz_lockptr = &keg->uk_lock;
1654 zone->uz_size = keg->uk_size;
1655 zone->uz_flags |= (keg->uk_flags &
1656 (UMA_ZONE_INHERIT | UMA_ZFLAG_INHERIT));
1659 * Some internal zones don't have room allocated for the per cpu
1660 * caches. If we're internal, bail out here.
1662 if (keg->uk_flags & UMA_ZFLAG_INTERNAL) {
1663 KASSERT((zone->uz_flags & UMA_ZONE_SECONDARY) == 0,
1664 ("Secondary zone requested UMA_ZFLAG_INTERNAL"));
1669 if ((arg->flags & UMA_ZONE_MAXBUCKET) == 0)
1670 zone->uz_count = bucket_select(zone->uz_size);
1672 zone->uz_count = BUCKET_MAX;
1673 zone->uz_count_min = zone->uz_count;
1679 * Keg header dtor. This frees all data, destroys locks, frees the hash
1680 * table and removes the keg from the global list.
1682 * Arguments/Returns follow uma_dtor specifications
1686 keg_dtor(void *arg, int size, void *udata)
1690 keg = (uma_keg_t)arg;
1692 if (keg->uk_free != 0) {
1693 printf("Freed UMA keg (%s) was not empty (%d items). "
1694 " Lost %d pages of memory.\n",
1695 keg->uk_name ? keg->uk_name : "",
1696 keg->uk_free, keg->uk_pages);
1700 hash_free(&keg->uk_hash);
1708 * Arguments/Returns follow uma_dtor specifications
1712 zone_dtor(void *arg, int size, void *udata)
1718 zone = (uma_zone_t)arg;
1719 keg = zone_first_keg(zone);
1721 if (!(zone->uz_flags & UMA_ZFLAG_INTERNAL))
1725 LIST_REMOVE(zone, uz_link);
1726 mtx_unlock(&uma_mtx);
1728 * XXX there are some races here where
1729 * the zone can be drained but zone lock
1730 * released and then refilled before we
1731 * remove it... we dont care for now
1733 zone_drain_wait(zone, M_WAITOK);
1735 * Unlink all of our kegs.
1737 while ((klink = LIST_FIRST(&zone->uz_kegs)) != NULL) {
1738 klink->kl_keg = NULL;
1739 LIST_REMOVE(klink, kl_link);
1740 if (klink == &zone->uz_klink)
1742 free(klink, M_TEMP);
1745 * We only destroy kegs from non secondary zones.
1747 if (keg != NULL && (zone->uz_flags & UMA_ZONE_SECONDARY) == 0) {
1749 LIST_REMOVE(keg, uk_link);
1750 mtx_unlock(&uma_mtx);
1751 zone_free_item(kegs, keg, NULL, SKIP_NONE);
1753 ZONE_LOCK_FINI(zone);
1757 * Traverses every zone in the system and calls a callback
1760 * zfunc A pointer to a function which accepts a zone
1767 zone_foreach(void (*zfunc)(uma_zone_t))
1773 LIST_FOREACH(keg, &uma_kegs, uk_link) {
1774 LIST_FOREACH(zone, &keg->uk_zones, uz_link)
1777 mtx_unlock(&uma_mtx);
1780 /* Public functions */
1783 uma_startup(void *bootmem, int boot_pages)
1785 struct uma_zctor_args args;
1791 printf("Creating uma keg headers zone and keg.\n");
1793 mtx_init(&uma_mtx, "UMA lock", NULL, MTX_DEF);
1795 /* "manually" create the initial zone */
1796 memset(&args, 0, sizeof(args));
1797 args.name = "UMA Kegs";
1798 args.size = sizeof(struct uma_keg);
1799 args.ctor = keg_ctor;
1800 args.dtor = keg_dtor;
1801 args.uminit = zero_init;
1803 args.keg = &masterkeg;
1804 args.align = 32 - 1;
1805 args.flags = UMA_ZFLAG_INTERNAL;
1806 /* The initial zone has no Per cpu queues so it's smaller */
1807 zone_ctor(kegs, sizeof(struct uma_zone), &args, M_WAITOK);
1810 printf("Filling boot free list.\n");
1812 for (i = 0; i < boot_pages; i++) {
1813 slab = (uma_slab_t)((uint8_t *)bootmem + (i * UMA_SLAB_SIZE));
1814 slab->us_data = (uint8_t *)slab;
1815 slab->us_flags = UMA_SLAB_BOOT;
1816 LIST_INSERT_HEAD(&uma_boot_pages, slab, us_link);
1818 mtx_init(&uma_boot_pages_mtx, "UMA boot pages", NULL, MTX_DEF);
1821 printf("Creating uma zone headers zone and keg.\n");
1823 args.name = "UMA Zones";
1824 args.size = sizeof(struct uma_zone) +
1825 (sizeof(struct uma_cache) * (mp_maxid + 1));
1826 args.ctor = zone_ctor;
1827 args.dtor = zone_dtor;
1828 args.uminit = zero_init;
1831 args.align = 32 - 1;
1832 args.flags = UMA_ZFLAG_INTERNAL;
1833 /* The initial zone has no Per cpu queues so it's smaller */
1834 zone_ctor(zones, sizeof(struct uma_zone), &args, M_WAITOK);
1837 printf("Initializing pcpu cache locks.\n");
1840 printf("Creating slab and hash zones.\n");
1843 /* Now make a zone for slab headers */
1844 slabzone = uma_zcreate("UMA Slabs",
1845 sizeof(struct uma_slab),
1846 NULL, NULL, NULL, NULL,
1847 UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
1850 * We also create a zone for the bigger slabs with reference
1851 * counts in them, to accomodate UMA_ZONE_REFCNT zones.
1853 slabsize = sizeof(struct uma_slab_refcnt);
1854 slabsize += uma_max_ipers_ref * sizeof(uint32_t);
1855 slabrefzone = uma_zcreate("UMA RCntSlabs",
1857 NULL, NULL, NULL, NULL,
1859 UMA_ZFLAG_INTERNAL);
1861 hashzone = uma_zcreate("UMA Hash",
1862 sizeof(struct slabhead *) * UMA_HASH_SIZE_INIT,
1863 NULL, NULL, NULL, NULL,
1864 UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
1868 booted = UMA_STARTUP;
1871 printf("UMA startup complete.\n");
1879 booted = UMA_STARTUP2;
1882 printf("UMA startup2 complete.\n");
1887 * Initialize our callout handle
1895 printf("Starting callout.\n");
1897 callout_init(&uma_callout, CALLOUT_MPSAFE);
1898 callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL);
1900 printf("UMA startup3 complete.\n");
1905 uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit, uma_fini fini,
1906 int align, uint32_t flags)
1908 struct uma_kctor_args args;
1911 args.uminit = uminit;
1913 args.align = (align == UMA_ALIGN_CACHE) ? uma_align_cache : align;
1916 return (zone_alloc_item(kegs, &args, M_WAITOK));
1921 uma_set_align(int align)
1924 if (align != UMA_ALIGN_CACHE)
1925 uma_align_cache = align;
1930 uma_zcreate(const char *name, size_t size, uma_ctor ctor, uma_dtor dtor,
1931 uma_init uminit, uma_fini fini, int align, uint32_t flags)
1934 struct uma_zctor_args args;
1936 /* This stuff is essential for the zone ctor */
1937 memset(&args, 0, sizeof(args));
1942 args.uminit = uminit;
1948 return (zone_alloc_item(zones, &args, M_WAITOK));
1953 uma_zsecond_create(char *name, uma_ctor ctor, uma_dtor dtor,
1954 uma_init zinit, uma_fini zfini, uma_zone_t master)
1956 struct uma_zctor_args args;
1959 keg = zone_first_keg(master);
1960 memset(&args, 0, sizeof(args));
1962 args.size = keg->uk_size;
1965 args.uminit = zinit;
1967 args.align = keg->uk_align;
1968 args.flags = keg->uk_flags | UMA_ZONE_SECONDARY;
1971 /* XXX Attaches only one keg of potentially many. */
1972 return (zone_alloc_item(zones, &args, M_WAITOK));
1977 uma_zcache_create(char *name, int size, uma_ctor ctor, uma_dtor dtor,
1978 uma_init zinit, uma_fini zfini, uma_import zimport,
1979 uma_release zrelease, void *arg, int flags)
1981 struct uma_zctor_args args;
1983 memset(&args, 0, sizeof(args));
1988 args.uminit = zinit;
1990 args.import = zimport;
1991 args.release = zrelease;
1996 return (zone_alloc_item(zones, &args, M_WAITOK));
2000 zone_lock_pair(uma_zone_t a, uma_zone_t b)
2004 mtx_lock_flags(b->uz_lockptr, MTX_DUPOK);
2007 mtx_lock_flags(a->uz_lockptr, MTX_DUPOK);
2012 zone_unlock_pair(uma_zone_t a, uma_zone_t b)
2020 uma_zsecond_add(uma_zone_t zone, uma_zone_t master)
2027 klink = malloc(sizeof(*klink), M_TEMP, M_WAITOK | M_ZERO);
2029 zone_lock_pair(zone, master);
2031 * zone must use vtoslab() to resolve objects and must already be
2034 if ((zone->uz_flags & (UMA_ZONE_VTOSLAB | UMA_ZONE_SECONDARY))
2035 != (UMA_ZONE_VTOSLAB | UMA_ZONE_SECONDARY)) {
2040 * The new master must also use vtoslab().
2042 if ((zone->uz_flags & UMA_ZONE_VTOSLAB) != UMA_ZONE_VTOSLAB) {
2047 * Both must either be refcnt, or not be refcnt.
2049 if ((zone->uz_flags & UMA_ZONE_REFCNT) !=
2050 (master->uz_flags & UMA_ZONE_REFCNT)) {
2055 * The underlying object must be the same size. rsize
2058 if (master->uz_size != zone->uz_size) {
2063 * Put it at the end of the list.
2065 klink->kl_keg = zone_first_keg(master);
2066 LIST_FOREACH(kl, &zone->uz_kegs, kl_link) {
2067 if (LIST_NEXT(kl, kl_link) == NULL) {
2068 LIST_INSERT_AFTER(kl, klink, kl_link);
2073 zone->uz_flags |= UMA_ZFLAG_MULTI;
2074 zone->uz_slab = zone_fetch_slab_multi;
2077 zone_unlock_pair(zone, master);
2079 free(klink, M_TEMP);
2087 uma_zdestroy(uma_zone_t zone)
2090 zone_free_item(zones, zone, NULL, SKIP_NONE);
2095 uma_zalloc_arg(uma_zone_t zone, void *udata, int flags)
2099 uma_bucket_t bucket;
2103 /* This is the fast path allocation */
2104 #ifdef UMA_DEBUG_ALLOC_1
2105 printf("Allocating one item from %s(%p)\n", zone->uz_name, zone);
2107 CTR3(KTR_UMA, "uma_zalloc_arg thread %x zone %s flags %d", curthread,
2108 zone->uz_name, flags);
2110 if (flags & M_WAITOK) {
2111 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
2112 "uma_zalloc_arg: zone \"%s\"", zone->uz_name);
2114 #ifdef DEBUG_MEMGUARD
2115 if (memguard_cmp_zone(zone)) {
2116 item = memguard_alloc(zone->uz_size, flags);
2119 * Avoid conflict with the use-after-free
2120 * protecting infrastructure from INVARIANTS.
2122 if (zone->uz_init != NULL &&
2123 zone->uz_init != mtrash_init &&
2124 zone->uz_init(item, zone->uz_size, flags) != 0)
2126 if (zone->uz_ctor != NULL &&
2127 zone->uz_ctor != mtrash_ctor &&
2128 zone->uz_ctor(item, zone->uz_size, udata,
2130 zone->uz_fini(item, zone->uz_size);
2135 /* This is unfortunate but should not be fatal. */
2139 * If possible, allocate from the per-CPU cache. There are two
2140 * requirements for safe access to the per-CPU cache: (1) the thread
2141 * accessing the cache must not be preempted or yield during access,
2142 * and (2) the thread must not migrate CPUs without switching which
2143 * cache it accesses. We rely on a critical section to prevent
2144 * preemption and migration. We release the critical section in
2145 * order to acquire the zone mutex if we are unable to allocate from
2146 * the current cache; when we re-acquire the critical section, we
2147 * must detect and handle migration if it has occurred.
2151 cache = &zone->uz_cpu[cpu];
2154 bucket = cache->uc_allocbucket;
2155 if (bucket != NULL && bucket->ub_cnt > 0) {
2157 item = bucket->ub_bucket[bucket->ub_cnt];
2159 bucket->ub_bucket[bucket->ub_cnt] = NULL;
2161 KASSERT(item != NULL, ("uma_zalloc: Bucket pointer mangled."));
2164 if (zone->uz_ctor != NULL &&
2165 zone->uz_ctor(item, zone->uz_size, udata, flags) != 0) {
2166 atomic_add_long(&zone->uz_fails, 1);
2167 zone_free_item(zone, item, udata, SKIP_DTOR);
2171 uma_dbg_alloc(zone, NULL, item);
2174 uma_zero_item(item, zone);
2179 * We have run out of items in our alloc bucket.
2180 * See if we can switch with our free bucket.
2182 bucket = cache->uc_freebucket;
2183 if (bucket != NULL && bucket->ub_cnt > 0) {
2184 #ifdef UMA_DEBUG_ALLOC
2185 printf("uma_zalloc: Swapping empty with alloc.\n");
2187 cache->uc_freebucket = cache->uc_allocbucket;
2188 cache->uc_allocbucket = bucket;
2193 * Discard any empty allocation bucket while we hold no locks.
2195 bucket = cache->uc_allocbucket;
2196 cache->uc_allocbucket = NULL;
2199 bucket_free(zone, bucket, udata);
2201 /* Short-circuit for zones without buckets and low memory. */
2202 if (zone->uz_count == 0 || bucketdisable)
2206 * Attempt to retrieve the item from the per-CPU cache has failed, so
2207 * we must go back to the zone. This requires the zone lock, so we
2208 * must drop the critical section, then re-acquire it when we go back
2209 * to the cache. Since the critical section is released, we may be
2210 * preempted or migrate. As such, make sure not to maintain any
2211 * thread-local state specific to the cache from prior to releasing
2212 * the critical section.
2215 if (ZONE_TRYLOCK(zone) == 0) {
2216 /* Record contention to size the buckets. */
2222 cache = &zone->uz_cpu[cpu];
2225 * Since we have locked the zone we may as well send back our stats.
2227 atomic_add_long(&zone->uz_allocs, cache->uc_allocs);
2228 atomic_add_long(&zone->uz_frees, cache->uc_frees);
2229 cache->uc_allocs = 0;
2230 cache->uc_frees = 0;
2232 /* See if we lost the race to fill the cache. */
2233 if (cache->uc_allocbucket != NULL) {
2239 * Check the zone's cache of buckets.
2241 if ((bucket = LIST_FIRST(&zone->uz_buckets)) != NULL) {
2242 KASSERT(bucket->ub_cnt != 0,
2243 ("uma_zalloc_arg: Returning an empty bucket."));
2245 LIST_REMOVE(bucket, ub_link);
2246 cache->uc_allocbucket = bucket;
2250 /* We are no longer associated with this CPU. */
2254 * We bump the uz count when the cache size is insufficient to
2255 * handle the working set.
2257 if (lockfail && zone->uz_count < BUCKET_MAX)
2262 * Now lets just fill a bucket and put it on the free list. If that
2263 * works we'll restart the allocation from the begining and it
2264 * will use the just filled bucket.
2266 bucket = zone_alloc_bucket(zone, udata, flags);
2267 if (bucket != NULL) {
2271 cache = &zone->uz_cpu[cpu];
2273 * See if we lost the race or were migrated. Cache the
2274 * initialized bucket to make this less likely or claim
2275 * the memory directly.
2277 if (cache->uc_allocbucket == NULL)
2278 cache->uc_allocbucket = bucket;
2280 LIST_INSERT_HEAD(&zone->uz_buckets, bucket, ub_link);
2286 * We may not be able to get a bucket so return an actual item.
2289 printf("uma_zalloc_arg: Bucketzone returned NULL\n");
2293 item = zone_alloc_item(zone, udata, flags);
2299 keg_fetch_slab(uma_keg_t keg, uma_zone_t zone, int flags)
2304 mtx_assert(&keg->uk_lock, MA_OWNED);
2307 if ((flags & M_USE_RESERVE) == 0)
2308 reserve = keg->uk_reserve;
2312 * Find a slab with some space. Prefer slabs that are partially
2313 * used over those that are totally full. This helps to reduce
2316 if (keg->uk_free > reserve) {
2317 if (!LIST_EMPTY(&keg->uk_part_slab)) {
2318 slab = LIST_FIRST(&keg->uk_part_slab);
2320 slab = LIST_FIRST(&keg->uk_free_slab);
2321 LIST_REMOVE(slab, us_link);
2322 LIST_INSERT_HEAD(&keg->uk_part_slab, slab,
2325 MPASS(slab->us_keg == keg);
2330 * M_NOVM means don't ask at all!
2335 if (keg->uk_maxpages && keg->uk_pages >= keg->uk_maxpages) {
2336 keg->uk_flags |= UMA_ZFLAG_FULL;
2338 * If this is not a multi-zone, set the FULL bit.
2339 * Otherwise slab_multi() takes care of it.
2341 if ((zone->uz_flags & UMA_ZFLAG_MULTI) == 0) {
2342 zone->uz_flags |= UMA_ZFLAG_FULL;
2343 zone_log_warning(zone);
2345 if (flags & M_NOWAIT)
2348 msleep(keg, &keg->uk_lock, PVM, "keglimit", 0);
2351 slab = keg_alloc_slab(keg, zone, flags);
2353 * If we got a slab here it's safe to mark it partially used
2354 * and return. We assume that the caller is going to remove
2355 * at least one item.
2358 MPASS(slab->us_keg == keg);
2359 LIST_INSERT_HEAD(&keg->uk_part_slab, slab, us_link);
2363 * We might not have been able to get a slab but another cpu
2364 * could have while we were unlocked. Check again before we
2373 zone_fetch_slab(uma_zone_t zone, uma_keg_t keg, int flags)
2378 keg = zone_first_keg(zone);
2383 slab = keg_fetch_slab(keg, zone, flags);
2386 if (flags & (M_NOWAIT | M_NOVM))
2394 * uma_zone_fetch_slab_multi: Fetches a slab from one available keg. Returns
2395 * with the keg locked. On NULL no lock is held.
2397 * The last pointer is used to seed the search. It is not required.
2400 zone_fetch_slab_multi(uma_zone_t zone, uma_keg_t last, int rflags)
2410 * Don't wait on the first pass. This will skip limit tests
2411 * as well. We don't want to block if we can find a provider
2414 flags = (rflags & ~M_WAITOK) | M_NOWAIT;
2416 * Use the last slab allocated as a hint for where to start
2420 slab = keg_fetch_slab(last, zone, flags);
2426 * Loop until we have a slab incase of transient failures
2427 * while M_WAITOK is specified. I'm not sure this is 100%
2428 * required but we've done it for so long now.
2434 * Search the available kegs for slabs. Be careful to hold the
2435 * correct lock while calling into the keg layer.
2437 LIST_FOREACH(klink, &zone->uz_kegs, kl_link) {
2438 keg = klink->kl_keg;
2440 if ((keg->uk_flags & UMA_ZFLAG_FULL) == 0) {
2441 slab = keg_fetch_slab(keg, zone, flags);
2445 if (keg->uk_flags & UMA_ZFLAG_FULL)
2451 if (rflags & (M_NOWAIT | M_NOVM))
2455 * All kegs are full. XXX We can't atomically check all kegs
2456 * and sleep so just sleep for a short period and retry.
2458 if (full && !empty) {
2460 zone->uz_flags |= UMA_ZFLAG_FULL;
2462 zone_log_warning(zone);
2463 msleep(zone, zone->uz_lockptr, PVM,
2464 "zonelimit", hz/100);
2465 zone->uz_flags &= ~UMA_ZFLAG_FULL;
2474 slab_alloc_item(uma_keg_t keg, uma_slab_t slab)
2479 MPASS(keg == slab->us_keg);
2480 mtx_assert(&keg->uk_lock, MA_OWNED);
2482 freei = BIT_FFS(SLAB_SETSIZE, &slab->us_free) - 1;
2483 BIT_CLR(SLAB_SETSIZE, freei, &slab->us_free);
2484 item = slab->us_data + (keg->uk_rsize * freei);
2485 slab->us_freecount--;
2488 /* Move this slab to the full list */
2489 if (slab->us_freecount == 0) {
2490 LIST_REMOVE(slab, us_link);
2491 LIST_INSERT_HEAD(&keg->uk_full_slab, slab, us_link);
2498 zone_import(uma_zone_t zone, void **bucket, int max, int flags)
2506 /* Try to keep the buckets totally full */
2507 for (i = 0; i < max; ) {
2508 if ((slab = zone->uz_slab(zone, keg, flags)) == NULL)
2511 while (slab->us_freecount && i < max) {
2512 bucket[i++] = slab_alloc_item(keg, slab);
2513 if (keg->uk_free <= keg->uk_reserve)
2516 /* Don't grab more than one slab at a time. */
2527 zone_alloc_bucket(uma_zone_t zone, void *udata, int flags)
2529 uma_bucket_t bucket;
2532 /* Don't wait for buckets, preserve caller's NOVM setting. */
2533 bucket = bucket_alloc(zone, udata, M_NOWAIT | (flags & M_NOVM));
2537 max = MIN(bucket->ub_entries, zone->uz_count);
2538 bucket->ub_cnt = zone->uz_import(zone->uz_arg, bucket->ub_bucket,
2542 * Initialize the memory if necessary.
2544 if (bucket->ub_cnt != 0 && zone->uz_init != NULL) {
2547 for (i = 0; i < bucket->ub_cnt; i++)
2548 if (zone->uz_init(bucket->ub_bucket[i], zone->uz_size,
2552 * If we couldn't initialize the whole bucket, put the
2553 * rest back onto the freelist.
2555 if (i != bucket->ub_cnt) {
2556 zone->uz_release(zone->uz_arg, &bucket->ub_bucket[i],
2557 bucket->ub_cnt - i);
2559 bzero(&bucket->ub_bucket[i],
2560 sizeof(void *) * (bucket->ub_cnt - i));
2566 if (bucket->ub_cnt == 0) {
2567 bucket_free(zone, bucket, udata);
2568 atomic_add_long(&zone->uz_fails, 1);
2576 * Allocates a single item from a zone.
2579 * zone The zone to alloc for.
2580 * udata The data to be passed to the constructor.
2581 * flags M_WAITOK, M_NOWAIT, M_ZERO.
2584 * NULL if there is no memory and M_NOWAIT is set
2585 * An item if successful
2589 zone_alloc_item(uma_zone_t zone, void *udata, int flags)
2595 #ifdef UMA_DEBUG_ALLOC
2596 printf("INTERNAL: Allocating one item from %s(%p)\n", zone->uz_name, zone);
2598 if (zone->uz_import(zone->uz_arg, &item, 1, flags) != 1)
2600 atomic_add_long(&zone->uz_allocs, 1);
2603 * We have to call both the zone's init (not the keg's init)
2604 * and the zone's ctor. This is because the item is going from
2605 * a keg slab directly to the user, and the user is expecting it
2606 * to be both zone-init'd as well as zone-ctor'd.
2608 if (zone->uz_init != NULL) {
2609 if (zone->uz_init(item, zone->uz_size, flags) != 0) {
2610 zone_free_item(zone, item, udata, SKIP_FINI);
2614 if (zone->uz_ctor != NULL) {
2615 if (zone->uz_ctor(item, zone->uz_size, udata, flags) != 0) {
2616 zone_free_item(zone, item, udata, SKIP_DTOR);
2621 uma_dbg_alloc(zone, NULL, item);
2624 uma_zero_item(item, zone);
2629 atomic_add_long(&zone->uz_fails, 1);
2635 uma_zfree_arg(uma_zone_t zone, void *item, void *udata)
2638 uma_bucket_t bucket;
2642 #ifdef UMA_DEBUG_ALLOC_1
2643 printf("Freeing item %p to %s(%p)\n", item, zone->uz_name, zone);
2645 CTR2(KTR_UMA, "uma_zfree_arg thread %x zone %s", curthread,
2648 /* uma_zfree(..., NULL) does nothing, to match free(9). */
2651 #ifdef DEBUG_MEMGUARD
2652 if (is_memguard_addr(item)) {
2653 if (zone->uz_dtor != NULL && zone->uz_dtor != mtrash_dtor)
2654 zone->uz_dtor(item, zone->uz_size, udata);
2655 if (zone->uz_fini != NULL && zone->uz_fini != mtrash_fini)
2656 zone->uz_fini(item, zone->uz_size);
2657 memguard_free(item);
2662 if (zone->uz_flags & UMA_ZONE_MALLOC)
2663 uma_dbg_free(zone, udata, item);
2665 uma_dbg_free(zone, NULL, item);
2667 if (zone->uz_dtor != NULL)
2668 zone->uz_dtor(item, zone->uz_size, udata);
2671 * The race here is acceptable. If we miss it we'll just have to wait
2672 * a little longer for the limits to be reset.
2674 if (zone->uz_flags & UMA_ZFLAG_FULL)
2678 * If possible, free to the per-CPU cache. There are two
2679 * requirements for safe access to the per-CPU cache: (1) the thread
2680 * accessing the cache must not be preempted or yield during access,
2681 * and (2) the thread must not migrate CPUs without switching which
2682 * cache it accesses. We rely on a critical section to prevent
2683 * preemption and migration. We release the critical section in
2684 * order to acquire the zone mutex if we are unable to free to the
2685 * current cache; when we re-acquire the critical section, we must
2686 * detect and handle migration if it has occurred.
2691 cache = &zone->uz_cpu[cpu];
2695 * Try to free into the allocbucket first to give LIFO ordering
2696 * for cache-hot datastructures. Spill over into the freebucket
2697 * if necessary. Alloc will swap them if one runs dry.
2699 bucket = cache->uc_allocbucket;
2700 if (bucket == NULL || bucket->ub_cnt >= bucket->ub_entries)
2701 bucket = cache->uc_freebucket;
2702 if (bucket != NULL && bucket->ub_cnt < bucket->ub_entries) {
2703 KASSERT(bucket->ub_bucket[bucket->ub_cnt] == NULL,
2704 ("uma_zfree: Freeing to non free bucket index."));
2705 bucket->ub_bucket[bucket->ub_cnt] = item;
2713 * We must go back the zone, which requires acquiring the zone lock,
2714 * which in turn means we must release and re-acquire the critical
2715 * section. Since the critical section is released, we may be
2716 * preempted or migrate. As such, make sure not to maintain any
2717 * thread-local state specific to the cache from prior to releasing
2718 * the critical section.
2721 if (zone->uz_count == 0 || bucketdisable)
2725 if (ZONE_TRYLOCK(zone) == 0) {
2726 /* Record contention to size the buckets. */
2732 cache = &zone->uz_cpu[cpu];
2735 * Since we have locked the zone we may as well send back our stats.
2737 atomic_add_long(&zone->uz_allocs, cache->uc_allocs);
2738 atomic_add_long(&zone->uz_frees, cache->uc_frees);
2739 cache->uc_allocs = 0;
2740 cache->uc_frees = 0;
2742 bucket = cache->uc_freebucket;
2743 if (bucket != NULL && bucket->ub_cnt < bucket->ub_entries) {
2747 cache->uc_freebucket = NULL;
2749 /* Can we throw this on the zone full list? */
2750 if (bucket != NULL) {
2751 #ifdef UMA_DEBUG_ALLOC
2752 printf("uma_zfree: Putting old bucket on the free list.\n");
2754 /* ub_cnt is pointing to the last free item */
2755 KASSERT(bucket->ub_cnt != 0,
2756 ("uma_zfree: Attempting to insert an empty bucket onto the full list.\n"));
2757 LIST_INSERT_HEAD(&zone->uz_buckets, bucket, ub_link);
2760 /* We are no longer associated with this CPU. */
2764 * We bump the uz count when the cache size is insufficient to
2765 * handle the working set.
2767 if (lockfail && zone->uz_count < BUCKET_MAX)
2771 #ifdef UMA_DEBUG_ALLOC
2772 printf("uma_zfree: Allocating new free bucket.\n");
2774 bucket = bucket_alloc(zone, udata, M_NOWAIT);
2778 cache = &zone->uz_cpu[cpu];
2779 if (cache->uc_freebucket == NULL) {
2780 cache->uc_freebucket = bucket;
2784 * We lost the race, start over. We have to drop our
2785 * critical section to free the bucket.
2788 bucket_free(zone, bucket, udata);
2793 * If nothing else caught this, we'll just do an internal free.
2796 zone_free_item(zone, item, udata, SKIP_DTOR);
2802 slab_free_item(uma_keg_t keg, uma_slab_t slab, void *item)
2806 mtx_assert(&keg->uk_lock, MA_OWNED);
2807 MPASS(keg == slab->us_keg);
2809 /* Do we need to remove from any lists? */
2810 if (slab->us_freecount+1 == keg->uk_ipers) {
2811 LIST_REMOVE(slab, us_link);
2812 LIST_INSERT_HEAD(&keg->uk_free_slab, slab, us_link);
2813 } else if (slab->us_freecount == 0) {
2814 LIST_REMOVE(slab, us_link);
2815 LIST_INSERT_HEAD(&keg->uk_part_slab, slab, us_link);
2818 /* Slab management. */
2819 freei = ((uintptr_t)item - (uintptr_t)slab->us_data) / keg->uk_rsize;
2820 BIT_SET(SLAB_SETSIZE, freei, &slab->us_free);
2821 slab->us_freecount++;
2823 /* Keg statistics. */
2828 zone_release(uma_zone_t zone, void **bucket, int cnt)
2838 keg = zone_first_keg(zone);
2840 for (i = 0; i < cnt; i++) {
2842 if (!(zone->uz_flags & UMA_ZONE_VTOSLAB)) {
2843 mem = (uint8_t *)((uintptr_t)item & (~UMA_SLAB_MASK));
2844 if (zone->uz_flags & UMA_ZONE_HASH) {
2845 slab = hash_sfind(&keg->uk_hash, mem);
2847 mem += keg->uk_pgoff;
2848 slab = (uma_slab_t)mem;
2851 slab = vtoslab((vm_offset_t)item);
2852 if (slab->us_keg != keg) {
2858 slab_free_item(keg, slab, item);
2859 if (keg->uk_flags & UMA_ZFLAG_FULL) {
2860 if (keg->uk_pages < keg->uk_maxpages) {
2861 keg->uk_flags &= ~UMA_ZFLAG_FULL;
2866 * We can handle one more allocation. Since we're
2867 * clearing ZFLAG_FULL, wake up all procs blocked
2868 * on pages. This should be uncommon, so keeping this
2869 * simple for now (rather than adding count of blocked
2878 zone->uz_flags &= ~UMA_ZFLAG_FULL;
2886 * Frees a single item to any zone.
2889 * zone The zone to free to
2890 * item The item we're freeing
2891 * udata User supplied data for the dtor
2892 * skip Skip dtors and finis
2895 zone_free_item(uma_zone_t zone, void *item, void *udata, enum zfreeskip skip)
2899 if (skip == SKIP_NONE) {
2900 if (zone->uz_flags & UMA_ZONE_MALLOC)
2901 uma_dbg_free(zone, udata, item);
2903 uma_dbg_free(zone, NULL, item);
2906 if (skip < SKIP_DTOR && zone->uz_dtor)
2907 zone->uz_dtor(item, zone->uz_size, udata);
2909 if (skip < SKIP_FINI && zone->uz_fini)
2910 zone->uz_fini(item, zone->uz_size);
2912 atomic_add_long(&zone->uz_frees, 1);
2913 zone->uz_release(zone->uz_arg, &item, 1);
2918 uma_zone_set_max(uma_zone_t zone, int nitems)
2922 keg = zone_first_keg(zone);
2926 keg->uk_maxpages = (nitems / keg->uk_ipers) * keg->uk_ppera;
2927 if (keg->uk_maxpages * keg->uk_ipers < nitems)
2928 keg->uk_maxpages += keg->uk_ppera;
2929 nitems = keg->uk_maxpages * keg->uk_ipers;
2937 uma_zone_get_max(uma_zone_t zone)
2942 keg = zone_first_keg(zone);
2946 nitems = keg->uk_maxpages * keg->uk_ipers;
2954 uma_zone_set_warning(uma_zone_t zone, const char *warning)
2958 zone->uz_warning = warning;
2964 uma_zone_get_cur(uma_zone_t zone)
2970 nitems = zone->uz_allocs - zone->uz_frees;
2973 * See the comment in sysctl_vm_zone_stats() regarding the
2974 * safety of accessing the per-cpu caches. With the zone lock
2975 * held, it is safe, but can potentially result in stale data.
2977 nitems += zone->uz_cpu[i].uc_allocs -
2978 zone->uz_cpu[i].uc_frees;
2982 return (nitems < 0 ? 0 : nitems);
2987 uma_zone_set_init(uma_zone_t zone, uma_init uminit)
2991 keg = zone_first_keg(zone);
2992 KASSERT(keg != NULL, ("uma_zone_set_init: Invalid zone type"));
2994 KASSERT(keg->uk_pages == 0,
2995 ("uma_zone_set_init on non-empty keg"));
2996 keg->uk_init = uminit;
3002 uma_zone_set_fini(uma_zone_t zone, uma_fini fini)
3006 keg = zone_first_keg(zone);
3007 KASSERT(keg != NULL, ("uma_zone_set_init: Invalid zone type"));
3009 KASSERT(keg->uk_pages == 0,
3010 ("uma_zone_set_fini on non-empty keg"));
3011 keg->uk_fini = fini;
3017 uma_zone_set_zinit(uma_zone_t zone, uma_init zinit)
3021 KASSERT(zone_first_keg(zone)->uk_pages == 0,
3022 ("uma_zone_set_zinit on non-empty keg"));
3023 zone->uz_init = zinit;
3029 uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini)
3033 KASSERT(zone_first_keg(zone)->uk_pages == 0,
3034 ("uma_zone_set_zfini on non-empty keg"));
3035 zone->uz_fini = zfini;
3040 /* XXX uk_freef is not actually used with the zone locked */
3042 uma_zone_set_freef(uma_zone_t zone, uma_free freef)
3046 keg = zone_first_keg(zone);
3047 KASSERT(keg != NULL, ("uma_zone_set_init: Invalid zone type"));
3049 keg->uk_freef = freef;
3054 /* XXX uk_allocf is not actually used with the zone locked */
3056 uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf)
3060 keg = zone_first_keg(zone);
3062 keg->uk_allocf = allocf;
3068 uma_zone_reserve(uma_zone_t zone, int items)
3072 keg = zone_first_keg(zone);
3076 keg->uk_reserve = items;
3084 uma_zone_reserve_kva(uma_zone_t zone, int count)
3090 keg = zone_first_keg(zone);
3093 pages = count / keg->uk_ipers;
3095 if (pages * keg->uk_ipers < count)
3098 #ifdef UMA_MD_SMALL_ALLOC
3099 if (keg->uk_ppera > 1) {
3103 kva = kva_alloc(pages * UMA_SLAB_SIZE);
3111 keg->uk_maxpages = pages;
3112 #ifdef UMA_MD_SMALL_ALLOC
3113 keg->uk_allocf = (keg->uk_ppera > 1) ? noobj_alloc : uma_small_alloc;
3115 keg->uk_allocf = noobj_alloc;
3117 keg->uk_flags |= UMA_ZONE_NOFREE;
3125 uma_prealloc(uma_zone_t zone, int items)
3131 keg = zone_first_keg(zone);
3135 slabs = items / keg->uk_ipers;
3136 if (slabs * keg->uk_ipers < items)
3139 slab = keg_alloc_slab(keg, zone, M_WAITOK);
3142 MPASS(slab->us_keg == keg);
3143 LIST_INSERT_HEAD(&keg->uk_free_slab, slab, us_link);
3151 uma_find_refcnt(uma_zone_t zone, void *item)
3153 uma_slabrefcnt_t slabref;
3159 slab = vtoslab((vm_offset_t)item & (~UMA_SLAB_MASK));
3160 slabref = (uma_slabrefcnt_t)slab;
3162 KASSERT(keg->uk_flags & UMA_ZONE_REFCNT,
3163 ("uma_find_refcnt(): zone possibly not UMA_ZONE_REFCNT"));
3164 idx = ((uintptr_t)item - (uintptr_t)slab->us_data) / keg->uk_rsize;
3165 refcnt = &slabref->us_refcnt[idx];
3174 printf("UMA: vm asked us to release pages!\n");
3177 zone_foreach(zone_drain);
3178 if (vm_page_count_min()) {
3179 cache_drain_safe(NULL);
3180 zone_foreach(zone_drain);
3183 * Some slabs may have been freed but this zone will be visited early
3184 * we visit again so that we can free pages that are empty once other
3185 * zones are drained. We have to do the same for buckets.
3187 zone_drain(slabzone);
3188 zone_drain(slabrefzone);
3189 bucket_zone_drain();
3194 uma_zone_exhausted(uma_zone_t zone)
3199 full = (zone->uz_flags & UMA_ZFLAG_FULL);
3205 uma_zone_exhausted_nolock(uma_zone_t zone)
3207 return (zone->uz_flags & UMA_ZFLAG_FULL);
3211 uma_large_malloc(int size, int wait)
3217 slab = zone_alloc_item(slabzone, NULL, wait);
3220 mem = page_alloc(NULL, size, &flags, wait);
3222 vsetslab((vm_offset_t)mem, slab);
3223 slab->us_data = mem;
3224 slab->us_flags = flags | UMA_SLAB_MALLOC;
3225 slab->us_size = size;
3227 zone_free_item(slabzone, slab, NULL, SKIP_NONE);
3234 uma_large_free(uma_slab_t slab)
3237 page_free(slab->us_data, slab->us_size, slab->us_flags);
3238 zone_free_item(slabzone, slab, NULL, SKIP_NONE);
3242 uma_zero_item(void *item, uma_zone_t zone)
3245 if (zone->uz_flags & UMA_ZONE_PCPU) {
3246 for (int i = 0; i < mp_ncpus; i++)
3247 bzero(zpcpu_get_cpu(item, i), zone->uz_size);
3249 bzero(item, zone->uz_size);
3253 uma_print_stats(void)
3255 zone_foreach(uma_print_zone);
3259 slab_print(uma_slab_t slab)
3261 printf("slab: keg %p, data %p, freecount %d\n",
3262 slab->us_keg, slab->us_data, slab->us_freecount);
3266 cache_print(uma_cache_t cache)
3268 printf("alloc: %p(%d), free: %p(%d)\n",
3269 cache->uc_allocbucket,
3270 cache->uc_allocbucket?cache->uc_allocbucket->ub_cnt:0,
3271 cache->uc_freebucket,
3272 cache->uc_freebucket?cache->uc_freebucket->ub_cnt:0);
3276 uma_print_keg(uma_keg_t keg)
3280 printf("keg: %s(%p) size %d(%d) flags %#x ipers %d ppera %d "
3281 "out %d free %d limit %d\n",
3282 keg->uk_name, keg, keg->uk_size, keg->uk_rsize, keg->uk_flags,
3283 keg->uk_ipers, keg->uk_ppera,
3284 (keg->uk_ipers * keg->uk_pages) - keg->uk_free, keg->uk_free,
3285 (keg->uk_maxpages / keg->uk_ppera) * keg->uk_ipers);
3286 printf("Part slabs:\n");
3287 LIST_FOREACH(slab, &keg->uk_part_slab, us_link)
3289 printf("Free slabs:\n");
3290 LIST_FOREACH(slab, &keg->uk_free_slab, us_link)
3292 printf("Full slabs:\n");
3293 LIST_FOREACH(slab, &keg->uk_full_slab, us_link)
3298 uma_print_zone(uma_zone_t zone)
3304 printf("zone: %s(%p) size %d flags %#x\n",
3305 zone->uz_name, zone, zone->uz_size, zone->uz_flags);
3306 LIST_FOREACH(kl, &zone->uz_kegs, kl_link)
3307 uma_print_keg(kl->kl_keg);
3309 cache = &zone->uz_cpu[i];
3310 printf("CPU %d Cache:\n", i);
3317 * Generate statistics across both the zone and its per-cpu cache's. Return
3318 * desired statistics if the pointer is non-NULL for that statistic.
3320 * Note: does not update the zone statistics, as it can't safely clear the
3321 * per-CPU cache statistic.
3323 * XXXRW: Following the uc_allocbucket and uc_freebucket pointers here isn't
3324 * safe from off-CPU; we should modify the caches to track this information
3325 * directly so that we don't have to.
3328 uma_zone_sumstat(uma_zone_t z, int *cachefreep, uint64_t *allocsp,
3329 uint64_t *freesp, uint64_t *sleepsp)
3332 uint64_t allocs, frees, sleeps;
3335 allocs = frees = sleeps = 0;
3338 cache = &z->uz_cpu[cpu];
3339 if (cache->uc_allocbucket != NULL)
3340 cachefree += cache->uc_allocbucket->ub_cnt;
3341 if (cache->uc_freebucket != NULL)
3342 cachefree += cache->uc_freebucket->ub_cnt;
3343 allocs += cache->uc_allocs;
3344 frees += cache->uc_frees;
3346 allocs += z->uz_allocs;
3347 frees += z->uz_frees;
3348 sleeps += z->uz_sleeps;
3349 if (cachefreep != NULL)
3350 *cachefreep = cachefree;
3351 if (allocsp != NULL)
3355 if (sleepsp != NULL)
3361 sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS)
3369 LIST_FOREACH(kz, &uma_kegs, uk_link) {
3370 LIST_FOREACH(z, &kz->uk_zones, uz_link)
3373 mtx_unlock(&uma_mtx);
3374 return (sysctl_handle_int(oidp, &count, 0, req));
3378 sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS)
3380 struct uma_stream_header ush;
3381 struct uma_type_header uth;
3382 struct uma_percpu_stat ups;
3383 uma_bucket_t bucket;
3390 int count, error, i;
3392 error = sysctl_wire_old_buffer(req, 0);
3395 sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
3399 LIST_FOREACH(kz, &uma_kegs, uk_link) {
3400 LIST_FOREACH(z, &kz->uk_zones, uz_link)
3405 * Insert stream header.
3407 bzero(&ush, sizeof(ush));
3408 ush.ush_version = UMA_STREAM_VERSION;
3409 ush.ush_maxcpus = (mp_maxid + 1);
3410 ush.ush_count = count;
3411 (void)sbuf_bcat(&sbuf, &ush, sizeof(ush));
3413 LIST_FOREACH(kz, &uma_kegs, uk_link) {
3414 LIST_FOREACH(z, &kz->uk_zones, uz_link) {
3415 bzero(&uth, sizeof(uth));
3417 strlcpy(uth.uth_name, z->uz_name, UTH_MAX_NAME);
3418 uth.uth_align = kz->uk_align;
3419 uth.uth_size = kz->uk_size;
3420 uth.uth_rsize = kz->uk_rsize;
3421 LIST_FOREACH(kl, &z->uz_kegs, kl_link) {
3423 uth.uth_maxpages += k->uk_maxpages;
3424 uth.uth_pages += k->uk_pages;
3425 uth.uth_keg_free += k->uk_free;
3426 uth.uth_limit = (k->uk_maxpages / k->uk_ppera)
3431 * A zone is secondary is it is not the first entry
3432 * on the keg's zone list.
3434 if ((z->uz_flags & UMA_ZONE_SECONDARY) &&
3435 (LIST_FIRST(&kz->uk_zones) != z))
3436 uth.uth_zone_flags = UTH_ZONE_SECONDARY;
3438 LIST_FOREACH(bucket, &z->uz_buckets, ub_link)
3439 uth.uth_zone_free += bucket->ub_cnt;
3440 uth.uth_allocs = z->uz_allocs;
3441 uth.uth_frees = z->uz_frees;
3442 uth.uth_fails = z->uz_fails;
3443 uth.uth_sleeps = z->uz_sleeps;
3444 (void)sbuf_bcat(&sbuf, &uth, sizeof(uth));
3446 * While it is not normally safe to access the cache
3447 * bucket pointers while not on the CPU that owns the
3448 * cache, we only allow the pointers to be exchanged
3449 * without the zone lock held, not invalidated, so
3450 * accept the possible race associated with bucket
3451 * exchange during monitoring.
3453 for (i = 0; i < (mp_maxid + 1); i++) {
3454 bzero(&ups, sizeof(ups));
3455 if (kz->uk_flags & UMA_ZFLAG_INTERNAL)
3459 cache = &z->uz_cpu[i];
3460 if (cache->uc_allocbucket != NULL)
3461 ups.ups_cache_free +=
3462 cache->uc_allocbucket->ub_cnt;
3463 if (cache->uc_freebucket != NULL)
3464 ups.ups_cache_free +=
3465 cache->uc_freebucket->ub_cnt;
3466 ups.ups_allocs = cache->uc_allocs;
3467 ups.ups_frees = cache->uc_frees;
3469 (void)sbuf_bcat(&sbuf, &ups, sizeof(ups));
3474 mtx_unlock(&uma_mtx);
3475 error = sbuf_finish(&sbuf);
3481 sysctl_handle_uma_zone_max(SYSCTL_HANDLER_ARGS)
3483 uma_zone_t zone = *(uma_zone_t *)arg1;
3484 int error, max, old;
3486 old = max = uma_zone_get_max(zone);
3487 error = sysctl_handle_int(oidp, &max, 0, req);
3488 if (error || !req->newptr)
3494 uma_zone_set_max(zone, max);
3500 sysctl_handle_uma_zone_cur(SYSCTL_HANDLER_ARGS)
3502 uma_zone_t zone = *(uma_zone_t *)arg1;
3505 cur = uma_zone_get_cur(zone);
3506 return (sysctl_handle_int(oidp, &cur, 0, req));
3510 DB_SHOW_COMMAND(uma, db_show_uma)
3512 uint64_t allocs, frees, sleeps;
3513 uma_bucket_t bucket;
3518 db_printf("%18s %8s %8s %8s %12s %8s %8s\n", "Zone", "Size", "Used",
3519 "Free", "Requests", "Sleeps", "Bucket");
3520 LIST_FOREACH(kz, &uma_kegs, uk_link) {
3521 LIST_FOREACH(z, &kz->uk_zones, uz_link) {
3522 if (kz->uk_flags & UMA_ZFLAG_INTERNAL) {
3523 allocs = z->uz_allocs;
3524 frees = z->uz_frees;
3525 sleeps = z->uz_sleeps;
3528 uma_zone_sumstat(z, &cachefree, &allocs,
3530 if (!((z->uz_flags & UMA_ZONE_SECONDARY) &&
3531 (LIST_FIRST(&kz->uk_zones) != z)))
3532 cachefree += kz->uk_free;
3533 LIST_FOREACH(bucket, &z->uz_buckets, ub_link)
3534 cachefree += bucket->ub_cnt;
3535 db_printf("%18s %8ju %8jd %8d %12ju %8ju %8u\n",
3536 z->uz_name, (uintmax_t)kz->uk_size,
3537 (intmax_t)(allocs - frees), cachefree,
3538 (uintmax_t)allocs, sleeps, z->uz_count);
3545 DB_SHOW_COMMAND(umacache, db_show_umacache)
3547 uint64_t allocs, frees;
3548 uma_bucket_t bucket;
3552 db_printf("%18s %8s %8s %8s %12s %8s\n", "Zone", "Size", "Used", "Free",
3553 "Requests", "Bucket");
3554 LIST_FOREACH(z, &uma_cachezones, uz_link) {
3555 uma_zone_sumstat(z, &cachefree, &allocs, &frees, NULL);
3556 LIST_FOREACH(bucket, &z->uz_buckets, ub_link)
3557 cachefree += bucket->ub_cnt;
3558 db_printf("%18s %8ju %8jd %8d %12ju %8u\n",
3559 z->uz_name, (uintmax_t)z->uz_size,
3560 (intmax_t)(allocs - frees), cachefree,
3561 (uintmax_t)allocs, z->uz_count);