1/*-
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
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice unmodified, this list of conditions, and the following
12 * disclaimer.
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.
16 *
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.
27 */
28
29/*
30 * uma_core.c Implementation of the Universal Memory allocator
31 *
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 * efficient. 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.
38 *
39 * The basic ideas stem from similar slab/zone based allocators whose algorithms
40 * are well known.
41 *
42 */
43
44/*
45 * TODO:
46 * - Improve memory usage for large allocations
47 * - Investigate cache size adjustments
48 */
49
50#include <sys/cdefs.h>
51__FBSDID("$FreeBSD: head/sys/vm/uma_core.c 302372 2016-07-06 14:09:49Z nwhitehorn $");
52
53/* I should really use ktr.. */
54/*
55#define UMA_DEBUG 1
56#define UMA_DEBUG_ALLOC 1
57#define UMA_DEBUG_ALLOC_1 1
58*/
59
60#include "opt_ddb.h"
61#include "opt_param.h"
62#include "opt_vm.h"
63
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>
71#include <sys/ktr.h>
72#include <sys/lock.h>
73#include <sys/sysctl.h>
74#include <sys/mutex.h>
75#include <sys/proc.h>
76#include <sys/random.h>
77#include <sys/rwlock.h>
78#include <sys/sbuf.h>
79#include <sys/sched.h>
80#include <sys/smp.h>
81#include <sys/taskqueue.h>
82#include <sys/vmmeter.h>
83
84#include <vm/vm.h>
85#include <vm/vm_object.h>
86#include <vm/vm_page.h>
87#include <vm/vm_pageout.h>
88#include <vm/vm_param.h>
89#include <vm/vm_map.h>
90#include <vm/vm_kern.h>
91#include <vm/vm_extern.h>
92#include <vm/uma.h>
93#include <vm/uma_int.h>
94#include <vm/uma_dbg.h>
95
96#include <ddb/ddb.h>
97
98#ifdef DEBUG_MEMGUARD
99#include <vm/memguard.h>
100#endif
101
102/*
103 * This is the zone and keg from which all zones are spawned. The idea is that
104 * even the zone & keg heads are allocated from the allocator, so we use the
105 * bss section to bootstrap us.
106 */
107static struct uma_keg masterkeg;
108static struct uma_zone masterzone_k;
109static struct uma_zone masterzone_z;
110static uma_zone_t kegs = &masterzone_k;
111static uma_zone_t zones = &masterzone_z;
112
113/* This is the zone from which all of uma_slab_t's are allocated. */
114static uma_zone_t slabzone;
115
116/*
117 * The initial hash tables come out of this zone so they can be allocated
118 * prior to malloc coming up.
119 */
120static uma_zone_t hashzone;
121
122/* The boot-time adjusted value for cache line alignment. */
123int uma_align_cache = 64 - 1;
124
125static MALLOC_DEFINE(M_UMAHASH, "UMAHash", "UMA Hash Buckets");
126
127/*
128 * Are we allowed to allocate buckets?
129 */
130static int bucketdisable = 1;
131
132/* Linked list of all kegs in the system */
133static LIST_HEAD(,uma_keg) uma_kegs = LIST_HEAD_INITIALIZER(uma_kegs);
134
135/* Linked list of all cache-only zones in the system */
136static LIST_HEAD(,uma_zone) uma_cachezones =
137 LIST_HEAD_INITIALIZER(uma_cachezones);
138
139/* This RW lock protects the keg list */
140static struct rwlock_padalign uma_rwlock;
141
142/* Linked list of boot time pages */
143static LIST_HEAD(,uma_slab) uma_boot_pages =
144 LIST_HEAD_INITIALIZER(uma_boot_pages);
145
146/* This mutex protects the boot time pages list */
147static struct mtx_padalign uma_boot_pages_mtx;
148
149static struct sx uma_drain_lock;
150
151/* Is the VM done starting up? */
152static int booted = 0;
153#define UMA_STARTUP 1
154#define UMA_STARTUP2 2
155
156/*
157 * This is the handle used to schedule events that need to happen
158 * outside of the allocation fast path.
159 */
160static struct callout uma_callout;
161#define UMA_TIMEOUT 20 /* Seconds for callout interval. */
162
163/*
164 * This structure is passed as the zone ctor arg so that I don't have to create
165 * a special allocation function just for zones.
166 */
167struct uma_zctor_args {
168 const char *name;
169 size_t size;
170 uma_ctor ctor;
171 uma_dtor dtor;
172 uma_init uminit;
173 uma_fini fini;
174 uma_import import;
175 uma_release release;
176 void *arg;
177 uma_keg_t keg;
178 int align;
179 uint32_t flags;
180};
181
182struct uma_kctor_args {
183 uma_zone_t zone;
184 size_t size;
185 uma_init uminit;
186 uma_fini fini;
187 int align;
188 uint32_t flags;
189};
190
191struct uma_bucket_zone {
192 uma_zone_t ubz_zone;
193 char *ubz_name;
194 int ubz_entries; /* Number of items it can hold. */
195 int ubz_maxsize; /* Maximum allocation size per-item. */
196};
197
198/*
199 * Compute the actual number of bucket entries to pack them in power
200 * of two sizes for more efficient space utilization.
201 */
202#define BUCKET_SIZE(n) \
203 (((sizeof(void *) * (n)) - sizeof(struct uma_bucket)) / sizeof(void *))
204
205#define BUCKET_MAX BUCKET_SIZE(256)
206
207struct uma_bucket_zone bucket_zones[] = {
208 { NULL, "4 Bucket", BUCKET_SIZE(4), 4096 },
209 { NULL, "6 Bucket", BUCKET_SIZE(6), 3072 },
210 { NULL, "8 Bucket", BUCKET_SIZE(8), 2048 },
211 { NULL, "12 Bucket", BUCKET_SIZE(12), 1536 },
212 { NULL, "16 Bucket", BUCKET_SIZE(16), 1024 },
213 { NULL, "32 Bucket", BUCKET_SIZE(32), 512 },
214 { NULL, "64 Bucket", BUCKET_SIZE(64), 256 },
215 { NULL, "128 Bucket", BUCKET_SIZE(128), 128 },
216 { NULL, "256 Bucket", BUCKET_SIZE(256), 64 },
217 { NULL, NULL, 0}
218};
219
220/*
221 * Flags and enumerations to be passed to internal functions.
222 */
223enum zfreeskip { SKIP_NONE = 0, SKIP_DTOR, SKIP_FINI };
224
225/* Prototypes.. */
226
227static void *noobj_alloc(uma_zone_t, vm_size_t, uint8_t *, int);
228static void *page_alloc(uma_zone_t, vm_size_t, uint8_t *, int);
229static void *startup_alloc(uma_zone_t, vm_size_t, uint8_t *, int);
230static void page_free(void *, vm_size_t, uint8_t);
231static uma_slab_t keg_alloc_slab(uma_keg_t, uma_zone_t, int);
232static void cache_drain(uma_zone_t);
233static void bucket_drain(uma_zone_t, uma_bucket_t);
234static void bucket_cache_drain(uma_zone_t zone);
235static int keg_ctor(void *, int, void *, int);
236static void keg_dtor(void *, int, void *);
237static int zone_ctor(void *, int, void *, int);
238static void zone_dtor(void *, int, void *);
239static int zero_init(void *, int, int);
240static void keg_small_init(uma_keg_t keg);
241static void keg_large_init(uma_keg_t keg);
242static void zone_foreach(void (*zfunc)(uma_zone_t));
243static void zone_timeout(uma_zone_t zone);
244static int hash_alloc(struct uma_hash *);
245static int hash_expand(struct uma_hash *, struct uma_hash *);
246static void hash_free(struct uma_hash *hash);
247static void uma_timeout(void *);
248static void uma_startup3(void);
249static void *zone_alloc_item(uma_zone_t, void *, int);
250static void zone_free_item(uma_zone_t, void *, void *, enum zfreeskip);
251static void bucket_enable(void);
252static void bucket_init(void);
253static uma_bucket_t bucket_alloc(uma_zone_t zone, void *, int);
254static void bucket_free(uma_zone_t zone, uma_bucket_t, void *);
255static void bucket_zone_drain(void);
256static uma_bucket_t zone_alloc_bucket(uma_zone_t zone, void *, int flags);
257static uma_slab_t zone_fetch_slab(uma_zone_t zone, uma_keg_t last, int flags);
258static uma_slab_t zone_fetch_slab_multi(uma_zone_t zone, uma_keg_t last, int flags);
259static void *slab_alloc_item(uma_keg_t keg, uma_slab_t slab);
260static void slab_free_item(uma_keg_t keg, uma_slab_t slab, void *item);
261static uma_keg_t uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit,
262 uma_fini fini, int align, uint32_t flags);
263static int zone_import(uma_zone_t zone, void **bucket, int max, int flags);
264static void zone_release(uma_zone_t zone, void **bucket, int cnt);
265static void uma_zero_item(void *item, uma_zone_t zone);
266
267void uma_print_zone(uma_zone_t);
268void uma_print_stats(void);
269static int sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS);
270static int sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS);
271
272#ifdef INVARIANTS
273static void uma_dbg_free(uma_zone_t zone, uma_slab_t slab, void *item);
274static void uma_dbg_alloc(uma_zone_t zone, uma_slab_t slab, void *item);
275#endif
276
277SYSINIT(uma_startup3, SI_SUB_VM_CONF, SI_ORDER_SECOND, uma_startup3, NULL);
278
279SYSCTL_PROC(_vm, OID_AUTO, zone_count, CTLFLAG_RD|CTLTYPE_INT,
280 0, 0, sysctl_vm_zone_count, "I", "Number of UMA zones");
281
282SYSCTL_PROC(_vm, OID_AUTO, zone_stats, CTLFLAG_RD|CTLTYPE_STRUCT,
283 0, 0, sysctl_vm_zone_stats, "s,struct uma_type_header", "Zone Stats");
284
285static int zone_warnings = 1;
286SYSCTL_INT(_vm, OID_AUTO, zone_warnings, CTLFLAG_RWTUN, &zone_warnings, 0,
287 "Warn when UMA zones becomes full");
288
289/*
290 * This routine checks to see whether or not it's safe to enable buckets.
291 */
292static void
293bucket_enable(void)
294{
295 bucketdisable = vm_page_count_min();
296}
297
298/*
299 * Initialize bucket_zones, the array of zones of buckets of various sizes.
300 *
301 * For each zone, calculate the memory required for each bucket, consisting
302 * of the header and an array of pointers.
303 */
304static void
305bucket_init(void)
306{
307 struct uma_bucket_zone *ubz;
308 int size;
309
310 for (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);
316 }
317}
318
319/*
320 * Given a desired number of entries for a bucket, return the zone from which
321 * to allocate the bucket.
322 */
323static struct uma_bucket_zone *
324bucket_zone_lookup(int entries)
325{
326 struct uma_bucket_zone *ubz;
327
328 for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++)
329 if (ubz->ubz_entries >= entries)
330 return (ubz);
331 ubz--;
332 return (ubz);
333}
334
335static int
336bucket_select(int size)
337{
338 struct uma_bucket_zone *ubz;
339
340 ubz = &bucket_zones[0];
341 if (size > ubz->ubz_maxsize)
342 return MAX((ubz->ubz_maxsize * ubz->ubz_entries) / size, 1);
343
344 for (; ubz->ubz_entries != 0; ubz++)
345 if (ubz->ubz_maxsize < size)
346 break;
347 ubz--;
348 return (ubz->ubz_entries);
349}
350
351static uma_bucket_t
352bucket_alloc(uma_zone_t zone, void *udata, int flags)
353{
354 struct uma_bucket_zone *ubz;
355 uma_bucket_t bucket;
356
357 /*
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.
362 */
363 if (bucketdisable)
364 return (NULL);
365 /*
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
373 * free path.
374 */
375 if ((zone->uz_flags & UMA_ZFLAG_BUCKET) == 0)
376 udata = (void *)(uintptr_t)zone->uz_flags;
377 else {
378 if ((uintptr_t)udata & UMA_ZFLAG_BUCKET)
379 return (NULL);
380 udata = (void *)((uintptr_t)udata | UMA_ZFLAG_BUCKET);
381 }
382 if ((uintptr_t)udata & UMA_ZFLAG_CACHEONLY)
383 flags |= M_NOVM;
384 ubz = bucket_zone_lookup(zone->uz_count);
385 if (ubz->ubz_zone == zone && (ubz + 1)->ubz_entries != 0)
386 ubz++;
387 bucket = uma_zalloc_arg(ubz->ubz_zone, udata, flags);
388 if (bucket) {
389#ifdef INVARIANTS
390 bzero(bucket->ub_bucket, sizeof(void *) * ubz->ubz_entries);
391#endif
392 bucket->ub_cnt = 0;
393 bucket->ub_entries = ubz->ubz_entries;
394 }
395
396 return (bucket);
397}
398
399static void
400bucket_free(uma_zone_t zone, uma_bucket_t bucket, void *udata)
401{
402 struct uma_bucket_zone *ubz;
403
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);
410}
411
412static void
413bucket_zone_drain(void)
414{
415 struct uma_bucket_zone *ubz;
416
417 for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++)
418 zone_drain(ubz->ubz_zone);
419}
420
421static void
422zone_log_warning(uma_zone_t zone)
423{
424 static const struct timeval warninterval = { 300, 0 };
425
426 if (!zone_warnings || zone->uz_warning == NULL)
427 return;
428
429 if (ratecheck(&zone->uz_ratecheck, &warninterval))
430 printf("[zone: %s] %s\n", zone->uz_name, zone->uz_warning);
431}
432
433static inline void
434zone_maxaction(uma_zone_t zone)
435{
436
437 if (zone->uz_maxaction.ta_func != NULL)
438 taskqueue_enqueue(taskqueue_thread, &zone->uz_maxaction);
439}
440
441static void
442zone_foreach_keg(uma_zone_t zone, void (*kegfn)(uma_keg_t))
443{
444 uma_klink_t klink;
445
446 LIST_FOREACH(klink, &zone->uz_kegs, kl_link)
447 kegfn(klink->kl_keg);
448}
449
450/*
451 * Routine called by timeout which is used to fire off some time interval
452 * based calculations. (stats, hash size, etc.)
453 *
454 * Arguments:
455 * arg Unused
456 *
457 * Returns:
458 * Nothing
459 */
460static void
461uma_timeout(void *unused)
462{
463 bucket_enable();
464 zone_foreach(zone_timeout);
465
466 /* Reschedule this event */
467 callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL);
468}
469
470/*
471 * Routine to perform timeout driven calculations. This expands the
472 * hashes and does per cpu statistics aggregation.
473 *
474 * Returns nothing.
475 */
476static void
477keg_timeout(uma_keg_t keg)
478{
479
480 KEG_LOCK(keg);
481 /*
482 * Expand the keg hash table.
483 *
484 * This is done if the number of slabs is larger than the hash size.
485 * What I'm trying to do here is completely reduce collisions. This
486 * may be a little aggressive. Should I allow for two collisions max?
487 */
488 if (keg->uk_flags & UMA_ZONE_HASH &&
489 keg->uk_pages / keg->uk_ppera >= keg->uk_hash.uh_hashsize) {
490 struct uma_hash newhash;
491 struct uma_hash oldhash;
492 int ret;
493
494 /*
495 * This is so involved because allocating and freeing
496 * while the keg lock is held will lead to deadlock.
497 * I have to do everything in stages and check for
498 * races.
499 */
500 newhash = keg->uk_hash;
501 KEG_UNLOCK(keg);
502 ret = hash_alloc(&newhash);
503 KEG_LOCK(keg);
504 if (ret) {
505 if (hash_expand(&keg->uk_hash, &newhash)) {
506 oldhash = keg->uk_hash;
507 keg->uk_hash = newhash;
508 } else
509 oldhash = newhash;
510
511 KEG_UNLOCK(keg);
512 hash_free(&oldhash);
513 return;
514 }
515 }
516 KEG_UNLOCK(keg);
517}
518
519static void
520zone_timeout(uma_zone_t zone)
521{
522
523 zone_foreach_keg(zone, &keg_timeout);
524}
525
526/*
527 * Allocate and zero fill the next sized hash table from the appropriate
528 * backing store.
529 *
530 * Arguments:
531 * hash A new hash structure with the old hash size in uh_hashsize
532 *
533 * Returns:
534 * 1 on success and 0 on failure.
535 */
536static int
537hash_alloc(struct uma_hash *hash)
538{
539 int oldsize;
540 int alloc;
541
542 oldsize = hash->uh_hashsize;
543
544 /* We're just going to go to a power of two greater */
545 if (oldsize) {
546 hash->uh_hashsize = oldsize * 2;
547 alloc = sizeof(hash->uh_slab_hash[0]) * hash->uh_hashsize;
548 hash->uh_slab_hash = (struct slabhead *)malloc(alloc,
549 M_UMAHASH, M_NOWAIT);
550 } else {
551 alloc = sizeof(hash->uh_slab_hash[0]) * UMA_HASH_SIZE_INIT;
552 hash->uh_slab_hash = zone_alloc_item(hashzone, NULL,
553 M_WAITOK);
554 hash->uh_hashsize = UMA_HASH_SIZE_INIT;
555 }
556 if (hash->uh_slab_hash) {
557 bzero(hash->uh_slab_hash, alloc);
558 hash->uh_hashmask = hash->uh_hashsize - 1;
559 return (1);
560 }
561
562 return (0);
563}
564
565/*
566 * Expands the hash table for HASH zones. This is done from zone_timeout
567 * to reduce collisions. This must not be done in the regular allocation
568 * path, otherwise, we can recurse on the vm while allocating pages.
569 *
570 * Arguments:
571 * oldhash The hash you want to expand
572 * newhash The hash structure for the new table
573 *
574 * Returns:
575 * Nothing
576 *
577 * Discussion:
578 */
579static int
580hash_expand(struct uma_hash *oldhash, struct uma_hash *newhash)
581{
582 uma_slab_t slab;
583 int hval;
584 int i;
585
586 if (!newhash->uh_slab_hash)
587 return (0);
588
589 if (oldhash->uh_hashsize >= newhash->uh_hashsize)
590 return (0);
591
592 /*
593 * I need to investigate hash algorithms for resizing without a
594 * full rehash.
595 */
596
597 for (i = 0; i < oldhash->uh_hashsize; i++)
598 while (!SLIST_EMPTY(&oldhash->uh_slab_hash[i])) {
599 slab = SLIST_FIRST(&oldhash->uh_slab_hash[i]);
600 SLIST_REMOVE_HEAD(&oldhash->uh_slab_hash[i], us_hlink);
601 hval = UMA_HASH(newhash, slab->us_data);
602 SLIST_INSERT_HEAD(&newhash->uh_slab_hash[hval],
603 slab, us_hlink);
604 }
605
606 return (1);
607}
608
609/*
610 * Free the hash bucket to the appropriate backing store.
611 *
612 * Arguments:
613 * slab_hash The hash bucket we're freeing
614 * hashsize The number of entries in that hash bucket
615 *
616 * Returns:
617 * Nothing
618 */
619static void
620hash_free(struct uma_hash *hash)
621{
622 if (hash->uh_slab_hash == NULL)
623 return;
624 if (hash->uh_hashsize == UMA_HASH_SIZE_INIT)
625 zone_free_item(hashzone, hash->uh_slab_hash, NULL, SKIP_NONE);
626 else
627 free(hash->uh_slab_hash, M_UMAHASH);
628}
629
630/*
631 * Frees all outstanding items in a bucket
632 *
633 * Arguments:
634 * zone The zone to free to, must be unlocked.
635 * bucket The free/alloc bucket with items, cpu queue must be locked.
636 *
637 * Returns:
638 * Nothing
639 */
640
641static void
642bucket_drain(uma_zone_t zone, uma_bucket_t bucket)
643{
644 int i;
645
646 if (bucket == NULL)
647 return;
648
649 if (zone->uz_fini)
650 for (i = 0; i < bucket->ub_cnt; i++)
651 zone->uz_fini(bucket->ub_bucket[i], zone->uz_size);
652 zone->uz_release(zone->uz_arg, bucket->ub_bucket, bucket->ub_cnt);
653 bucket->ub_cnt = 0;
654}
655
656/*
657 * Drains the per cpu caches for a zone.
658 *
659 * NOTE: This may only be called while the zone is being turn down, and not
660 * during normal operation. This is necessary in order that we do not have
661 * to migrate CPUs to drain the per-CPU caches.
662 *
663 * Arguments:
664 * zone The zone to drain, must be unlocked.
665 *
666 * Returns:
667 * Nothing
668 */
669static void
670cache_drain(uma_zone_t zone)
671{
672 uma_cache_t cache;
673 int cpu;
674
675 /*
676 * XXX: It is safe to not lock the per-CPU caches, because we're
677 * tearing down the zone anyway. I.e., there will be no further use
678 * of the caches at this point.
679 *
680 * XXX: It would good to be able to assert that the zone is being
681 * torn down to prevent improper use of cache_drain().
682 *
683 * XXX: We lock the zone before passing into bucket_cache_drain() as
684 * it is used elsewhere. Should the tear-down path be made special
685 * there in some form?
686 */
687 CPU_FOREACH(cpu) {
688 cache = &zone->uz_cpu[cpu];
689 bucket_drain(zone, cache->uc_allocbucket);
690 bucket_drain(zone, cache->uc_freebucket);
691 if (cache->uc_allocbucket != NULL)
692 bucket_free(zone, cache->uc_allocbucket, NULL);
693 if (cache->uc_freebucket != NULL)
694 bucket_free(zone, cache->uc_freebucket, NULL);
695 cache->uc_allocbucket = cache->uc_freebucket = NULL;
696 }
697 ZONE_LOCK(zone);
698 bucket_cache_drain(zone);
699 ZONE_UNLOCK(zone);
700}
701
702static void
703cache_shrink(uma_zone_t zone)
704{
705
706 if (zone->uz_flags & UMA_ZFLAG_INTERNAL)
707 return;
708
709 ZONE_LOCK(zone);
710 zone->uz_count = (zone->uz_count_min + zone->uz_count) / 2;
711 ZONE_UNLOCK(zone);
712}
713
714static void
715cache_drain_safe_cpu(uma_zone_t zone)
716{
717 uma_cache_t cache;
718 uma_bucket_t b1, b2;
719
720 if (zone->uz_flags & UMA_ZFLAG_INTERNAL)
721 return;
722
723 b1 = b2 = NULL;
724 ZONE_LOCK(zone);
725 critical_enter();
726 cache = &zone->uz_cpu[curcpu];
727 if (cache->uc_allocbucket) {
728 if (cache->uc_allocbucket->ub_cnt != 0)
729 LIST_INSERT_HEAD(&zone->uz_buckets,
730 cache->uc_allocbucket, ub_link);
731 else
732 b1 = cache->uc_allocbucket;
733 cache->uc_allocbucket = NULL;
734 }
735 if (cache->uc_freebucket) {
736 if (cache->uc_freebucket->ub_cnt != 0)
737 LIST_INSERT_HEAD(&zone->uz_buckets,
738 cache->uc_freebucket, ub_link);
739 else
740 b2 = cache->uc_freebucket;
741 cache->uc_freebucket = NULL;
742 }
743 critical_exit();
744 ZONE_UNLOCK(zone);
745 if (b1)
746 bucket_free(zone, b1, NULL);
747 if (b2)
748 bucket_free(zone, b2, NULL);
749}
750
751/*
752 * Safely drain per-CPU caches of a zone(s) to alloc bucket.
753 * This is an expensive call because it needs to bind to all CPUs
754 * one by one and enter a critical section on each of them in order
755 * to safely access their cache buckets.
756 * Zone lock must not be held on call this function.
757 */
758static void
759cache_drain_safe(uma_zone_t zone)
760{
761 int cpu;
762
763 /*
764 * Polite bucket sizes shrinking was not enouth, shrink aggressively.
765 */
766 if (zone)
767 cache_shrink(zone);
768 else
769 zone_foreach(cache_shrink);
770
771 CPU_FOREACH(cpu) {
772 thread_lock(curthread);
773 sched_bind(curthread, cpu);
774 thread_unlock(curthread);
775
776 if (zone)
777 cache_drain_safe_cpu(zone);
778 else
779 zone_foreach(cache_drain_safe_cpu);
780 }
781 thread_lock(curthread);
782 sched_unbind(curthread);
783 thread_unlock(curthread);
784}
785
786/*
787 * Drain the cached buckets from a zone. Expects a locked zone on entry.
788 */
789static void
790bucket_cache_drain(uma_zone_t zone)
791{
792 uma_bucket_t bucket;
793
794 /*
795 * Drain the bucket queues and free the buckets, we just keep two per
796 * cpu (alloc/free).
797 */
798 while ((bucket = LIST_FIRST(&zone->uz_buckets)) != NULL) {
799 LIST_REMOVE(bucket, ub_link);
800 ZONE_UNLOCK(zone);
801 bucket_drain(zone, bucket);
802 bucket_free(zone, bucket, NULL);
803 ZONE_LOCK(zone);
804 }
805
806 /*
807 * Shrink further bucket sizes. Price of single zone lock collision
808 * is probably lower then price of global cache drain.
809 */
810 if (zone->uz_count > zone->uz_count_min)
811 zone->uz_count--;
812}
813
814static void
815keg_free_slab(uma_keg_t keg, uma_slab_t slab, int start)
816{
817 uint8_t *mem;
818 int i;
819 uint8_t flags;
820
821 mem = slab->us_data;
822 flags = slab->us_flags;
823 i = start;
824 if (keg->uk_fini != NULL) {
825 for (i--; i > -1; i--)
826 keg->uk_fini(slab->us_data + (keg->uk_rsize * i),
827 keg->uk_size);
828 }
829 if (keg->uk_flags & UMA_ZONE_OFFPAGE)
830 zone_free_item(keg->uk_slabzone, slab, NULL, SKIP_NONE);
831#ifdef UMA_DEBUG
832 printf("%s: Returning %d bytes.\n", keg->uk_name,
833 PAGE_SIZE * keg->uk_ppera);
834#endif
835 keg->uk_freef(mem, PAGE_SIZE * keg->uk_ppera, flags);
836}
837
838/*
839 * Frees pages from a keg back to the system. This is done on demand from
840 * the pageout daemon.
841 *
842 * Returns nothing.
843 */
844static void
845keg_drain(uma_keg_t keg)
846{
847 struct slabhead freeslabs = { 0 };
848 uma_slab_t slab;
849 uma_slab_t n;
850
851 /*
852 * We don't want to take pages from statically allocated kegs at this
853 * time
854 */
855 if (keg->uk_flags & UMA_ZONE_NOFREE || keg->uk_freef == NULL)
856 return;
857
858#ifdef UMA_DEBUG
859 printf("%s free items: %u\n", keg->uk_name, keg->uk_free);
860#endif
861 KEG_LOCK(keg);
862 if (keg->uk_free == 0)
863 goto finished;
864
865 slab = LIST_FIRST(&keg->uk_free_slab);
866 while (slab) {
867 n = LIST_NEXT(slab, us_link);
868
869 /* We have no where to free these to */
870 if (slab->us_flags & UMA_SLAB_BOOT) {
871 slab = n;
872 continue;
873 }
874
875 LIST_REMOVE(slab, us_link);
876 keg->uk_pages -= keg->uk_ppera;
877 keg->uk_free -= keg->uk_ipers;
878
879 if (keg->uk_flags & UMA_ZONE_HASH)
880 UMA_HASH_REMOVE(&keg->uk_hash, slab, slab->us_data);
881
882 SLIST_INSERT_HEAD(&freeslabs, slab, us_hlink);
883
884 slab = n;
885 }
886finished:
887 KEG_UNLOCK(keg);
888
889 while ((slab = SLIST_FIRST(&freeslabs)) != NULL) {
890 SLIST_REMOVE(&freeslabs, slab, uma_slab, us_hlink);
891 keg_free_slab(keg, slab, keg->uk_ipers);
892 }
893}
894
895static void
896zone_drain_wait(uma_zone_t zone, int waitok)
897{
898
899 /*
900 * Set draining to interlock with zone_dtor() so we can release our
901 * locks as we go. Only dtor() should do a WAITOK call since it
902 * is the only call that knows the structure will still be available
903 * when it wakes up.
904 */
905 ZONE_LOCK(zone);
906 while (zone->uz_flags & UMA_ZFLAG_DRAINING) {
907 if (waitok == M_NOWAIT)
908 goto out;
909 msleep(zone, zone->uz_lockptr, PVM, "zonedrain", 1);
910 }
911 zone->uz_flags |= UMA_ZFLAG_DRAINING;
912 bucket_cache_drain(zone);
913 ZONE_UNLOCK(zone);
914 /*
915 * The DRAINING flag protects us from being freed while
916 * we're running. Normally the uma_rwlock would protect us but we
917 * must be able to release and acquire the right lock for each keg.
918 */
919 zone_foreach_keg(zone, &keg_drain);
920 ZONE_LOCK(zone);
921 zone->uz_flags &= ~UMA_ZFLAG_DRAINING;
922 wakeup(zone);
923out:
924 ZONE_UNLOCK(zone);
925}
926
927void
928zone_drain(uma_zone_t zone)
929{
930
931 zone_drain_wait(zone, M_NOWAIT);
932}
933
934/*
935 * Allocate a new slab for a keg. This does not insert the slab onto a list.
936 *
937 * Arguments:
938 * wait Shall we wait?
939 *
940 * Returns:
941 * The slab that was allocated or NULL if there is no memory and the
942 * caller specified M_NOWAIT.
943 */
944static uma_slab_t
945keg_alloc_slab(uma_keg_t keg, uma_zone_t zone, int wait)
946{
947 uma_alloc allocf;
948 uma_slab_t slab;
949 uint8_t *mem;
950 uint8_t flags;
951 int i;
952
953 mtx_assert(&keg->uk_lock, MA_OWNED);
954 slab = NULL;
955 mem = NULL;
956
957#ifdef UMA_DEBUG
958 printf("alloc_slab: Allocating a new slab for %s\n", keg->uk_name);
959#endif
960 allocf = keg->uk_allocf;
961 KEG_UNLOCK(keg);
962
963 if (keg->uk_flags & UMA_ZONE_OFFPAGE) {
964 slab = zone_alloc_item(keg->uk_slabzone, NULL, wait);
965 if (slab == NULL)
966 goto out;
967 }
968
969 /*
970 * This reproduces the old vm_zone behavior of zero filling pages the
971 * first time they are added to a zone.
972 *
973 * Malloced items are zeroed in uma_zalloc.
974 */
975
976 if ((keg->uk_flags & UMA_ZONE_MALLOC) == 0)
977 wait |= M_ZERO;
978 else
979 wait &= ~M_ZERO;
980
981 if (keg->uk_flags & UMA_ZONE_NODUMP)
982 wait |= M_NODUMP;
983
984 /* zone is passed for legacy reasons. */
985 mem = allocf(zone, keg->uk_ppera * PAGE_SIZE, &flags, wait);
986 if (mem == NULL) {
987 if (keg->uk_flags & UMA_ZONE_OFFPAGE)
988 zone_free_item(keg->uk_slabzone, slab, NULL, SKIP_NONE);
989 slab = NULL;
990 goto out;
991 }
992
993 /* Point the slab into the allocated memory */
994 if (!(keg->uk_flags & UMA_ZONE_OFFPAGE))
995 slab = (uma_slab_t )(mem + keg->uk_pgoff);
996
997 if (keg->uk_flags & UMA_ZONE_VTOSLAB)
998 for (i = 0; i < keg->uk_ppera; i++)
999 vsetslab((vm_offset_t)mem + (i * PAGE_SIZE), slab);
1000
1001 slab->us_keg = keg;
1002 slab->us_data = mem;
1003 slab->us_freecount = keg->uk_ipers;
1004 slab->us_flags = flags;
1005 BIT_FILL(SLAB_SETSIZE, &slab->us_free);
1006#ifdef INVARIANTS
1007 BIT_ZERO(SLAB_SETSIZE, &slab->us_debugfree);
1008#endif
1009
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)
1014 break;
1015 if (i != keg->uk_ipers) {
1016 keg_free_slab(keg, slab, i);
1017 slab = NULL;
1018 goto out;
1019 }
1020 }
1021out:
1022 KEG_LOCK(keg);
1023
1024 if (slab != NULL) {
1025 if (keg->uk_flags & UMA_ZONE_HASH)
1026 UMA_HASH_INSERT(&keg->uk_hash, slab, mem);
1027
1028 keg->uk_pages += keg->uk_ppera;
1029 keg->uk_free += keg->uk_ipers;
1030 }
1031
1032 return (slab);
1033}
1034
1035/*
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
1038 * the VM is ready.
1039 */
1040static void *
1041startup_alloc(uma_zone_t zone, vm_size_t bytes, uint8_t *pflag, int wait)
1042{
1043 uma_keg_t keg;
1044 uma_slab_t tmps;
1045 int pages, check_pages;
1046
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"));
1051
1052 /*
1053 * Check our small startup cache to see if it has pages remaining.
1054 */
1055 mtx_lock(&uma_boot_pages_mtx);
1056
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);
1061 if (tmps != NULL) {
1062 /*
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.
1066 */
1067 while (pages-- > 0) {
1068 tmps = LIST_FIRST(&uma_boot_pages);
1069 LIST_REMOVE(tmps, us_link);
1070 }
1071 mtx_unlock(&uma_boot_pages_mtx);
1072 *pflag = tmps->us_flags;
1073 return (tmps->us_data);
1074 }
1075 mtx_unlock(&uma_boot_pages_mtx);
1076 if (booted < UMA_STARTUP2)
1077 panic("UMA: Increase vm.boot_pages");
1078 /*
1079 * Now that we've booted reset these users to their real allocator.
1080 */
1081#ifdef UMA_MD_SMALL_ALLOC
1082 keg->uk_allocf = (keg->uk_ppera > 1) ? page_alloc : uma_small_alloc;
1083#else
1084 keg->uk_allocf = page_alloc;
1085#endif
1086 return keg->uk_allocf(zone, bytes, pflag, wait);
1087}
1088
1089/*
1090 * Allocates a number of pages from the system
1091 *
1092 * Arguments:
1093 * bytes The number of bytes requested
1094 * wait Shall we wait?
1095 *
1096 * Returns:
1097 * A pointer to the alloced memory or possibly
1098 * NULL if M_NOWAIT is set.
1099 */
1100static void *
1101page_alloc(uma_zone_t zone, vm_size_t bytes, uint8_t *pflag, int wait)
1102{
1103 void *p; /* Returned page */
1104
1105 *pflag = UMA_SLAB_KMEM;
1106 p = (void *) kmem_malloc(kmem_arena, bytes, wait);
1107
1108 return (p);
1109}
1110
1111/*
1112 * Allocates a number of pages from within an object
1113 *
1114 * Arguments:
1115 * bytes The number of bytes requested
1116 * wait Shall we wait?
1117 *
1118 * Returns:
1119 * A pointer to the alloced memory or possibly
1120 * NULL if M_NOWAIT is set.
1121 */
1122static void *
1123noobj_alloc(uma_zone_t zone, vm_size_t bytes, uint8_t *flags, int wait)
1124{
1125 TAILQ_HEAD(, vm_page) alloctail;
1126 u_long npages;
1127 vm_offset_t retkva, zkva;
1128 vm_page_t p, p_next;
1129 uma_keg_t keg;
1130
1131 TAILQ_INIT(&alloctail);
1132 keg = zone_first_keg(zone);
1133
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);
1138 if (p != NULL) {
1139 /*
1140 * Since the page does not belong to an object, its
1141 * listq is unused.
1142 */
1143 TAILQ_INSERT_TAIL(&alloctail, p, listq);
1144 npages--;
1145 continue;
1146 }
1147 if (wait & M_WAITOK) {
1148 VM_WAIT;
1149 continue;
1150 }
1151
1152 /*
1153 * Page allocation failed, free intermediate pages and
1154 * exit.
1155 */
1156 TAILQ_FOREACH_SAFE(p, &alloctail, listq, p_next) {
1157 vm_page_unwire(p, PQ_NONE);
1158 vm_page_free(p);
1159 }
1160 return (NULL);
1161 }
1162 *flags = UMA_SLAB_PRIV;
1163 zkva = keg->uk_kva +
1164 atomic_fetchadd_long(&keg->uk_offset, round_page(bytes));
1165 retkva = zkva;
1166 TAILQ_FOREACH(p, &alloctail, listq) {
1167 pmap_qenter(zkva, &p, 1);
1168 zkva += PAGE_SIZE;
1169 }
1170
1171 return ((void *)retkva);
1172}
1173
1174/*
1175 * Frees a number of pages to the system
1176 *
1177 * Arguments:
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
1181 *
1182 * Returns:
1183 * Nothing
1184 */
1185static void
1186page_free(void *mem, vm_size_t size, uint8_t flags)
1187{
1188 struct vmem *vmem;
1189
1190 if (flags & UMA_SLAB_KMEM)
1191 vmem = kmem_arena;
1192 else if (flags & UMA_SLAB_KERNEL)
1193 vmem = kernel_arena;
1194 else
1195 panic("UMA: page_free used with invalid flags %d", flags);
1196
1197 kmem_free(vmem, (vm_offset_t)mem, size);
1198}
1199
1200/*
1201 * Zero fill initializer
1202 *
1203 * Arguments/Returns follow uma_init specifications
1204 */
1205static int
1206zero_init(void *mem, int size, int flags)
1207{
1208 bzero(mem, size);
1209 return (0);
1210}
1211
1212/*
1213 * Finish creating a small uma keg. This calculates ipers, and the keg size.
1214 *
1215 * Arguments
1216 * keg The zone we should initialize
1217 *
1218 * Returns
1219 * Nothing
1220 */
1221static void
1222keg_small_init(uma_keg_t keg)
1223{
1224 u_int rsize;
1225 u_int memused;
1226 u_int wastedspace;
1227 u_int shsize;
1228
1229 if (keg->uk_flags & UMA_ZONE_PCPU) {
1230 u_int ncpus = (mp_maxid + 1) ? (mp_maxid + 1) : MAXCPU;
1231
1232 keg->uk_slabsize = sizeof(struct pcpu);
1233 keg->uk_ppera = howmany(ncpus * sizeof(struct pcpu),
1234 PAGE_SIZE);
1235 } else {
1236 keg->uk_slabsize = UMA_SLAB_SIZE;
1237 keg->uk_ppera = 1;
1238 }
1239
1240 /*
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.
1244 */
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;
1251
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));
1255
1256 if (keg->uk_flags & UMA_ZONE_OFFPAGE)
1257 shsize = 0;
1258 else
1259 shsize = sizeof(struct uma_slab);
1260
1261 keg->uk_ipers = (keg->uk_slabsize - shsize) / rsize;
1262 KASSERT(keg->uk_ipers > 0 && keg->uk_ipers <= SLAB_SETSIZE,
1263 ("%s: keg->uk_ipers %u", __func__, keg->uk_ipers));
1264
1265 memused = keg->uk_ipers * rsize + shsize;
1266 wastedspace = keg->uk_slabsize - memused;
1267
1268 /*
1269 * We can't do OFFPAGE if we're internal or if we've been
1270 * asked to not go to the VM for buckets. If we do this we
1271 * may end up going to the VM for slabs which we do not
1272 * want to do if we're UMA_ZFLAG_CACHEONLY as a result
1273 * of UMA_ZONE_VM, which clearly forbids it.
1274 */
1275 if ((keg->uk_flags & UMA_ZFLAG_INTERNAL) ||
1276 (keg->uk_flags & UMA_ZFLAG_CACHEONLY))
1277 return;
1278
1279 /*
1280 * See if using an OFFPAGE slab will limit our waste. Only do
1281 * this if it permits more items per-slab.
1282 *
1283 * XXX We could try growing slabsize to limit max waste as well.
1284 * Historically this was not done because the VM could not
1285 * efficiently handle contiguous allocations.
1286 */
1287 if ((wastedspace >= keg->uk_slabsize / UMA_MAX_WASTE) &&
1288 (keg->uk_ipers < (keg->uk_slabsize / keg->uk_rsize))) {
1289 keg->uk_ipers = keg->uk_slabsize / keg->uk_rsize;
1290 KASSERT(keg->uk_ipers > 0 && keg->uk_ipers <= SLAB_SETSIZE,
1291 ("%s: keg->uk_ipers %u", __func__, keg->uk_ipers));
1292#ifdef UMA_DEBUG
1293 printf("UMA decided we need offpage slab headers for "
1294 "keg: %s, calculated wastedspace = %d, "
1295 "maximum wasted space allowed = %d, "
1296 "calculated ipers = %d, "
1297 "new wasted space = %d\n", keg->uk_name, wastedspace,
1298 keg->uk_slabsize / UMA_MAX_WASTE, keg->uk_ipers,
1299 keg->uk_slabsize - keg->uk_ipers * keg->uk_rsize);
1300#endif
1301 keg->uk_flags |= UMA_ZONE_OFFPAGE;
1302 }
1303
1304 if ((keg->uk_flags & UMA_ZONE_OFFPAGE) &&
1305 (keg->uk_flags & UMA_ZONE_VTOSLAB) == 0)
1306 keg->uk_flags |= UMA_ZONE_HASH;
1307}
1308
1309/*
1310 * Finish creating a large (> UMA_SLAB_SIZE) uma kegs. Just give in and do
1311 * OFFPAGE for now. When I can allow for more dynamic slab sizes this will be
1312 * more complicated.
1313 *
1314 * Arguments
1315 * keg The keg we should initialize
1316 *
1317 * Returns
1318 * Nothing
1319 */
1320static void
1321keg_large_init(uma_keg_t keg)
1322{
1323 u_int shsize;
1324
1325 KASSERT(keg != NULL, ("Keg is null in keg_large_init"));
1326 KASSERT((keg->uk_flags & UMA_ZFLAG_CACHEONLY) == 0,
1327 ("keg_large_init: Cannot large-init a UMA_ZFLAG_CACHEONLY keg"));
1328 KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0,
1329 ("%s: Cannot large-init a UMA_ZONE_PCPU keg", __func__));
1330
1331 keg->uk_ppera = howmany(keg->uk_size, PAGE_SIZE);
1332 keg->uk_slabsize = keg->uk_ppera * PAGE_SIZE;
1333 keg->uk_ipers = 1;
1334 keg->uk_rsize = keg->uk_size;
1335
1336 /* We can't do OFFPAGE if we're internal, bail out here. */
1337 if (keg->uk_flags & UMA_ZFLAG_INTERNAL)
1338 return;
1339
1340 /* Check whether we have enough space to not do OFFPAGE. */
1341 if ((keg->uk_flags & UMA_ZONE_OFFPAGE) == 0) {
1342 shsize = sizeof(struct uma_slab);
1343 if (shsize & UMA_ALIGN_PTR)
1344 shsize = (shsize & ~UMA_ALIGN_PTR) +
1345 (UMA_ALIGN_PTR + 1);
1346
1347 if ((PAGE_SIZE * keg->uk_ppera) - keg->uk_rsize < shsize)
1348 keg->uk_flags |= UMA_ZONE_OFFPAGE;
1349 }
1350
1351 if ((keg->uk_flags & UMA_ZONE_OFFPAGE) &&
1352 (keg->uk_flags & UMA_ZONE_VTOSLAB) == 0)
1353 keg->uk_flags |= UMA_ZONE_HASH;
1354}
1355
1356static void
1357keg_cachespread_init(uma_keg_t keg)
1358{
1359 int alignsize;
1360 int trailer;
1361 int pages;
1362 int rsize;
1363
1364 KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0,
1365 ("%s: Cannot cachespread-init a UMA_ZONE_PCPU keg", __func__));
1366
1367 alignsize = keg->uk_align + 1;
1368 rsize = keg->uk_size;
1369 /*
1370 * We want one item to start on every align boundary in a page. To
1371 * do this we will span pages. We will also extend the item by the
1372 * size of align if it is an even multiple of align. Otherwise, it
1373 * would fall on the same boundary every time.
1374 */
1375 if (rsize & keg->uk_align)
1376 rsize = (rsize & ~keg->uk_align) + alignsize;
1377 if ((rsize & alignsize) == 0)
1378 rsize += alignsize;
1379 trailer = rsize - keg->uk_size;
1380 pages = (rsize * (PAGE_SIZE / alignsize)) / PAGE_SIZE;
1381 pages = MIN(pages, (128 * 1024) / PAGE_SIZE);
1382 keg->uk_rsize = rsize;
1383 keg->uk_ppera = pages;
1384 keg->uk_slabsize = UMA_SLAB_SIZE;
1385 keg->uk_ipers = ((pages * PAGE_SIZE) + trailer) / rsize;
1386 keg->uk_flags |= UMA_ZONE_OFFPAGE | UMA_ZONE_VTOSLAB;
1387 KASSERT(keg->uk_ipers <= SLAB_SETSIZE,
1388 ("%s: keg->uk_ipers too high(%d) increase max_ipers", __func__,
1389 keg->uk_ipers));
1390}
1391
1392/*
1393 * Keg header ctor. This initializes all fields, locks, etc. And inserts
1394 * the keg onto the global keg list.
1395 *
1396 * Arguments/Returns follow uma_ctor specifications
1397 * udata Actually uma_kctor_args
1398 */
1399static int
1400keg_ctor(void *mem, int size, void *udata, int flags)
1401{
1402 struct uma_kctor_args *arg = udata;
1403 uma_keg_t keg = mem;
1404 uma_zone_t zone;
1405
1406 bzero(keg, size);
1407 keg->uk_size = arg->size;
1408 keg->uk_init = arg->uminit;
1409 keg->uk_fini = arg->fini;
1410 keg->uk_align = arg->align;
1411 keg->uk_free = 0;
1412 keg->uk_reserve = 0;
1413 keg->uk_pages = 0;
1414 keg->uk_flags = arg->flags;
1415 keg->uk_allocf = page_alloc;
1416 keg->uk_freef = page_free;
1417 keg->uk_slabzone = NULL;
1418
1419 /*
1420 * The master zone is passed to us at keg-creation time.
1421 */
1422 zone = arg->zone;
1423 keg->uk_name = zone->uz_name;
1424
1425 if (arg->flags & UMA_ZONE_VM)
1426 keg->uk_flags |= UMA_ZFLAG_CACHEONLY;
1427
1428 if (arg->flags & UMA_ZONE_ZINIT)
1429 keg->uk_init = zero_init;
1430
1431 if (arg->flags & UMA_ZONE_MALLOC)
1432 keg->uk_flags |= UMA_ZONE_VTOSLAB;
1433
1434 if (arg->flags & UMA_ZONE_PCPU)
1435#ifdef SMP
1436 keg->uk_flags |= UMA_ZONE_OFFPAGE;
1437#else
1438 keg->uk_flags &= ~UMA_ZONE_PCPU;
1439#endif
1440
1441 if (keg->uk_flags & UMA_ZONE_CACHESPREAD) {
1442 keg_cachespread_init(keg);
1443 } else {
1444 if (keg->uk_size > (UMA_SLAB_SIZE - sizeof(struct uma_slab)))
1445 keg_large_init(keg);
1446 else
1447 keg_small_init(keg);
1448 }
1449
1450 if (keg->uk_flags & UMA_ZONE_OFFPAGE)
1451 keg->uk_slabzone = slabzone;
1452
1453 /*
1454 * If we haven't booted yet we need allocations to go through the
1455 * startup cache until the vm is ready.
1456 */
1457 if (keg->uk_ppera == 1) {
1458#ifdef UMA_MD_SMALL_ALLOC
1459 keg->uk_allocf = uma_small_alloc;
1460 keg->uk_freef = uma_small_free;
1461
1462 if (booted < UMA_STARTUP)
1463 keg->uk_allocf = startup_alloc;
1464#else
1465 if (booted < UMA_STARTUP2)
1466 keg->uk_allocf = startup_alloc;
1467#endif
1468 } else if (booted < UMA_STARTUP2 &&
1469 (keg->uk_flags & UMA_ZFLAG_INTERNAL))
1470 keg->uk_allocf = startup_alloc;
1471
1472 /*
1473 * Initialize keg's lock
1474 */
1475 KEG_LOCK_INIT(keg, (arg->flags & UMA_ZONE_MTXCLASS));
1476
1477 /*
1478 * If we're putting the slab header in the actual page we need to
1479 * figure out where in each page it goes. This calculates a right
1480 * justified offset into the memory on an ALIGN_PTR boundary.
1481 */
1482 if (!(keg->uk_flags & UMA_ZONE_OFFPAGE)) {
1483 u_int totsize;
1484
1485 /* Size of the slab struct and free list */
1486 totsize = sizeof(struct uma_slab);
1487
1488 if (totsize & UMA_ALIGN_PTR)
1489 totsize = (totsize & ~UMA_ALIGN_PTR) +
1490 (UMA_ALIGN_PTR + 1);
1491 keg->uk_pgoff = (PAGE_SIZE * keg->uk_ppera) - totsize;
1492
1493 /*
1494 * The only way the following is possible is if with our
1495 * UMA_ALIGN_PTR adjustments we are now bigger than
1496 * UMA_SLAB_SIZE. I haven't checked whether this is
1497 * mathematically possible for all cases, so we make
1498 * sure here anyway.
1499 */
1500 totsize = keg->uk_pgoff + sizeof(struct uma_slab);
1501 if (totsize > PAGE_SIZE * keg->uk_ppera) {
1502 printf("zone %s ipers %d rsize %d size %d\n",
1503 zone->uz_name, keg->uk_ipers, keg->uk_rsize,
1504 keg->uk_size);
1505 panic("UMA slab won't fit.");
1506 }
1507 }
1508
1509 if (keg->uk_flags & UMA_ZONE_HASH)
1510 hash_alloc(&keg->uk_hash);
1511
1512#ifdef UMA_DEBUG
1513 printf("UMA: %s(%p) size %d(%d) flags %#x ipers %d ppera %d out %d free %d\n",
1514 zone->uz_name, zone, keg->uk_size, keg->uk_rsize, keg->uk_flags,
1515 keg->uk_ipers, keg->uk_ppera,
1516 (keg->uk_ipers * keg->uk_pages) - keg->uk_free, keg->uk_free);
1517#endif
1518
1519 LIST_INSERT_HEAD(&keg->uk_zones, zone, uz_link);
1520
1521 rw_wlock(&uma_rwlock);
1522 LIST_INSERT_HEAD(&uma_kegs, keg, uk_link);
1523 rw_wunlock(&uma_rwlock);
1524 return (0);
1525}
1526
1527/*
1528 * Zone header ctor. This initializes all fields, locks, etc.
1529 *
1530 * Arguments/Returns follow uma_ctor specifications
1531 * udata Actually uma_zctor_args
1532 */
1533static int
1534zone_ctor(void *mem, int size, void *udata, int flags)
1535{
1536 struct uma_zctor_args *arg = udata;
1537 uma_zone_t zone = mem;
1538 uma_zone_t z;
1539 uma_keg_t keg;
1540
1541 bzero(zone, size);
1542 zone->uz_name = arg->name;
1543 zone->uz_ctor = arg->ctor;
1544 zone->uz_dtor = arg->dtor;
1545 zone->uz_slab = zone_fetch_slab;
1546 zone->uz_init = NULL;
1547 zone->uz_fini = NULL;
1548 zone->uz_allocs = 0;
1549 zone->uz_frees = 0;
1550 zone->uz_fails = 0;
1551 zone->uz_sleeps = 0;
1552 zone->uz_count = 0;
1553 zone->uz_count_min = 0;
1554 zone->uz_flags = 0;
1555 zone->uz_warning = NULL;
1556 timevalclear(&zone->uz_ratecheck);
1557 keg = arg->keg;
1558
1559 ZONE_LOCK_INIT(zone, (arg->flags & UMA_ZONE_MTXCLASS));
1560
1561 /*
1562 * This is a pure cache zone, no kegs.
1563 */
1564 if (arg->import) {
1565 if (arg->flags & UMA_ZONE_VM)
1566 arg->flags |= UMA_ZFLAG_CACHEONLY;
1567 zone->uz_flags = arg->flags;
1568 zone->uz_size = arg->size;
1569 zone->uz_import = arg->import;
1570 zone->uz_release = arg->release;
1571 zone->uz_arg = arg->arg;
1572 zone->uz_lockptr = &zone->uz_lock;
1573 rw_wlock(&uma_rwlock);
1574 LIST_INSERT_HEAD(&uma_cachezones, zone, uz_link);
1575 rw_wunlock(&uma_rwlock);
1576 goto out;
1577 }
1578
1579 /*
1580 * Use the regular zone/keg/slab allocator.
1581 */
1582 zone->uz_import = (uma_import)zone_import;
1583 zone->uz_release = (uma_release)zone_release;
1584 zone->uz_arg = zone;
1585
1586 if (arg->flags & UMA_ZONE_SECONDARY) {
1587 KASSERT(arg->keg != NULL, ("Secondary zone on zero'd keg"));
1588 zone->uz_init = arg->uminit;
1589 zone->uz_fini = arg->fini;
1590 zone->uz_lockptr = &keg->uk_lock;
1591 zone->uz_flags |= UMA_ZONE_SECONDARY;
1592 rw_wlock(&uma_rwlock);
1593 ZONE_LOCK(zone);
1594 LIST_FOREACH(z, &keg->uk_zones, uz_link) {
1595 if (LIST_NEXT(z, uz_link) == NULL) {
1596 LIST_INSERT_AFTER(z, zone, uz_link);
1597 break;
1598 }
1599 }
1600 ZONE_UNLOCK(zone);
1601 rw_wunlock(&uma_rwlock);
1602 } else if (keg == NULL) {
1603 if ((keg = uma_kcreate(zone, arg->size, arg->uminit, arg->fini,
1604 arg->align, arg->flags)) == NULL)
1605 return (ENOMEM);
1606 } else {
1607 struct uma_kctor_args karg;
1608 int error;
1609
1610 /* We should only be here from uma_startup() */
1611 karg.size = arg->size;
1612 karg.uminit = arg->uminit;
1613 karg.fini = arg->fini;
1614 karg.align = arg->align;
1615 karg.flags = arg->flags;
1616 karg.zone = zone;
1617 error = keg_ctor(arg->keg, sizeof(struct uma_keg), &karg,
1618 flags);
1619 if (error)
1620 return (error);
1621 }
1622
1623 /*
1624 * Link in the first keg.
1625 */
1626 zone->uz_klink.kl_keg = keg;
1627 LIST_INSERT_HEAD(&zone->uz_kegs, &zone->uz_klink, kl_link);
1628 zone->uz_lockptr = &keg->uk_lock;
1629 zone->uz_size = keg->uk_size;
1630 zone->uz_flags |= (keg->uk_flags &
1631 (UMA_ZONE_INHERIT | UMA_ZFLAG_INHERIT));
1632
1633 /*
1634 * Some internal zones don't have room allocated for the per cpu
1635 * caches. If we're internal, bail out here.
1636 */
1637 if (keg->uk_flags & UMA_ZFLAG_INTERNAL) {
1638 KASSERT((zone->uz_flags & UMA_ZONE_SECONDARY) == 0,
1639 ("Secondary zone requested UMA_ZFLAG_INTERNAL"));
1640 return (0);
1641 }
1642
1643out:
1644 if ((arg->flags & UMA_ZONE_MAXBUCKET) == 0)
1645 zone->uz_count = bucket_select(zone->uz_size);
1646 else
1647 zone->uz_count = BUCKET_MAX;
1648 zone->uz_count_min = zone->uz_count;
1649
1650 return (0);
1651}
1652
1653/*
1654 * Keg header dtor. This frees all data, destroys locks, frees the hash
1655 * table and removes the keg from the global list.
1656 *
1657 * Arguments/Returns follow uma_dtor specifications
1658 * udata unused
1659 */
1660static void
1661keg_dtor(void *arg, int size, void *udata)
1662{
1663 uma_keg_t keg;
1664
1665 keg = (uma_keg_t)arg;
1666 KEG_LOCK(keg);
1667 if (keg->uk_free != 0) {
1668 printf("Freed UMA keg (%s) was not empty (%d items). "
1669 " Lost %d pages of memory.\n",
1670 keg->uk_name ? keg->uk_name : "",
1671 keg->uk_free, keg->uk_pages);
1672 }
1673 KEG_UNLOCK(keg);
1674
1675 hash_free(&keg->uk_hash);
1676
1677 KEG_LOCK_FINI(keg);
1678}
1679
1680/*
1681 * Zone header dtor.
1682 *
1683 * Arguments/Returns follow uma_dtor specifications
1684 * udata unused
1685 */
1686static void
1687zone_dtor(void *arg, int size, void *udata)
1688{
1689 uma_klink_t klink;
1690 uma_zone_t zone;
1691 uma_keg_t keg;
1692
1693 zone = (uma_zone_t)arg;
1694 keg = zone_first_keg(zone);
1695
1696 if (!(zone->uz_flags & UMA_ZFLAG_INTERNAL))
1697 cache_drain(zone);
1698
1699 rw_wlock(&uma_rwlock);
1700 LIST_REMOVE(zone, uz_link);
1701 rw_wunlock(&uma_rwlock);
1702 /*
1703 * XXX there are some races here where
1704 * the zone can be drained but zone lock
1705 * released and then refilled before we
1706 * remove it... we dont care for now
1707 */
1708 zone_drain_wait(zone, M_WAITOK);
1709 /*
1710 * Unlink all of our kegs.
1711 */
1712 while ((klink = LIST_FIRST(&zone->uz_kegs)) != NULL) {
1713 klink->kl_keg = NULL;
1714 LIST_REMOVE(klink, kl_link);
1715 if (klink == &zone->uz_klink)
1716 continue;
1717 free(klink, M_TEMP);
1718 }
1719 /*
1720 * We only destroy kegs from non secondary zones.
1721 */
1722 if (keg != NULL && (zone->uz_flags & UMA_ZONE_SECONDARY) == 0) {
1723 rw_wlock(&uma_rwlock);
1724 LIST_REMOVE(keg, uk_link);
1725 rw_wunlock(&uma_rwlock);
1726 zone_free_item(kegs, keg, NULL, SKIP_NONE);
1727 }
1728 ZONE_LOCK_FINI(zone);
1729}
1730
1731/*
1732 * Traverses every zone in the system and calls a callback
1733 *
1734 * Arguments:
1735 * zfunc A pointer to a function which accepts a zone
1736 * as an argument.
1737 *
1738 * Returns:
1739 * Nothing
1740 */
1741static void
1742zone_foreach(void (*zfunc)(uma_zone_t))
1743{
1744 uma_keg_t keg;
1745 uma_zone_t zone;
1746
1747 rw_rlock(&uma_rwlock);
1748 LIST_FOREACH(keg, &uma_kegs, uk_link) {
1749 LIST_FOREACH(zone, &keg->uk_zones, uz_link)
1750 zfunc(zone);
1751 }
1752 rw_runlock(&uma_rwlock);
1753}
1754
1755/* Public functions */
1756/* See uma.h */
1757void
1758uma_startup(void *bootmem, int boot_pages)
1759{
1760 struct uma_zctor_args args;
1761 uma_slab_t slab;
1762 int i;
1763
1764#ifdef UMA_DEBUG
1765 printf("Creating uma keg headers zone and keg.\n");
1766#endif
1767 rw_init(&uma_rwlock, "UMA lock");
1768
1769 /* "manually" create the initial zone */
1770 memset(&args, 0, sizeof(args));
1771 args.name = "UMA Kegs";
1772 args.size = sizeof(struct uma_keg);
1773 args.ctor = keg_ctor;
1774 args.dtor = keg_dtor;
1775 args.uminit = zero_init;
1776 args.fini = NULL;
1777 args.keg = &masterkeg;
1778 args.align = 32 - 1;
1779 args.flags = UMA_ZFLAG_INTERNAL;
1780 /* The initial zone has no Per cpu queues so it's smaller */
1781 zone_ctor(kegs, sizeof(struct uma_zone), &args, M_WAITOK);
1782
1783#ifdef UMA_DEBUG
1784 printf("Filling boot free list.\n");
1785#endif
1786 for (i = 0; i < boot_pages; i++) {
1787 slab = (uma_slab_t)((uint8_t *)bootmem + (i * UMA_SLAB_SIZE));
1788 slab->us_data = (uint8_t *)slab;
1789 slab->us_flags = UMA_SLAB_BOOT;
1790 LIST_INSERT_HEAD(&uma_boot_pages, slab, us_link);
1791 }
1792 mtx_init(&uma_boot_pages_mtx, "UMA boot pages", NULL, MTX_DEF);
1793
1794#ifdef UMA_DEBUG
1795 printf("Creating uma zone headers zone and keg.\n");
1796#endif
1797 args.name = "UMA Zones";
1798 args.size = sizeof(struct uma_zone) +
1799 (sizeof(struct uma_cache) * (mp_maxid + 1));
1800 args.ctor = zone_ctor;
1801 args.dtor = zone_dtor;
1802 args.uminit = zero_init;
1803 args.fini = NULL;
1804 args.keg = NULL;
1805 args.align = 32 - 1;
1806 args.flags = UMA_ZFLAG_INTERNAL;
1807 /* The initial zone has no Per cpu queues so it's smaller */
1808 zone_ctor(zones, sizeof(struct uma_zone), &args, M_WAITOK);
1809
1810#ifdef UMA_DEBUG
1811 printf("Creating slab and hash zones.\n");
1812#endif
1813
1814 /* Now make a zone for slab headers */
1815 slabzone = uma_zcreate("UMA Slabs",
1816 sizeof(struct uma_slab),
1817 NULL, NULL, NULL, NULL,
1818 UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
1819
1820 hashzone = uma_zcreate("UMA Hash",
1821 sizeof(struct slabhead *) * UMA_HASH_SIZE_INIT,
1822 NULL, NULL, NULL, NULL,
1823 UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
1824
1825 bucket_init();
1826
1827 booted = UMA_STARTUP;
1828
1829#ifdef UMA_DEBUG
1830 printf("UMA startup complete.\n");
1831#endif
1832}
1833
1834/* see uma.h */
1835void
1836uma_startup2(void)
1837{
1838 booted = UMA_STARTUP2;
1839 bucket_enable();
1840 sx_init(&uma_drain_lock, "umadrain");
1841#ifdef UMA_DEBUG
1842 printf("UMA startup2 complete.\n");
1843#endif
1844}
1845
1846/*
1847 * Initialize our callout handle
1848 *
1849 */
1850
1851static void
1852uma_startup3(void)
1853{
1854#ifdef UMA_DEBUG
1855 printf("Starting callout.\n");
1856#endif
1857 callout_init(&uma_callout, 1);
1858 callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL);
1859#ifdef UMA_DEBUG
1860 printf("UMA startup3 complete.\n");
1861#endif
1862}
1863
1864static uma_keg_t
1865uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit, uma_fini fini,
1866 int align, uint32_t flags)
1867{
1868 struct uma_kctor_args args;
1869
1870 args.size = size;
1871 args.uminit = uminit;
1872 args.fini = fini;
1873 args.align = (align == UMA_ALIGN_CACHE) ? uma_align_cache : align;
1874 args.flags = flags;
1875 args.zone = zone;
1876 return (zone_alloc_item(kegs, &args, M_WAITOK));
1877}
1878
1879/* See uma.h */
1880void
1881uma_set_align(int align)
1882{
1883
1884 if (align != UMA_ALIGN_CACHE)
1885 uma_align_cache = align;
1886}
1887
1888/* See uma.h */
1889uma_zone_t
1890uma_zcreate(const char *name, size_t size, uma_ctor ctor, uma_dtor dtor,
1891 uma_init uminit, uma_fini fini, int align, uint32_t flags)
1892
1893{
1894 struct uma_zctor_args args;
1895 uma_zone_t res;
1896 bool locked;
1897
1898 /* This stuff is essential for the zone ctor */
1899 memset(&args, 0, sizeof(args));
1900 args.name = name;
1901 args.size = size;
1902 args.ctor = ctor;
1903 args.dtor = dtor;
1904 args.uminit = uminit;
1905 args.fini = fini;
1906#ifdef INVARIANTS
1907 /*
1908 * If a zone is being created with an empty constructor and
1909 * destructor, pass UMA constructor/destructor which checks for
1910 * memory use after free.
1911 */
1912 if ((!(flags & (UMA_ZONE_ZINIT | UMA_ZONE_NOFREE))) &&
1913 ctor == NULL && dtor == NULL && uminit == NULL && fini == NULL) {
1914 args.ctor = trash_ctor;
1915 args.dtor = trash_dtor;
1916 args.uminit = trash_init;
1917 args.fini = trash_fini;
1918 }
1919#endif
1920 args.align = align;
1921 args.flags = flags;
1922 args.keg = NULL;
1923
1924 if (booted < UMA_STARTUP2) {
1925 locked = false;
1926 } else {
1927 sx_slock(&uma_drain_lock);
1928 locked = true;
1929 }
1930 res = zone_alloc_item(zones, &args, M_WAITOK);
1931 if (locked)
1932 sx_sunlock(&uma_drain_lock);
1933 return (res);
1934}
1935
1936/* See uma.h */
1937uma_zone_t
1938uma_zsecond_create(char *name, uma_ctor ctor, uma_dtor dtor,
1939 uma_init zinit, uma_fini zfini, uma_zone_t master)
1940{
1941 struct uma_zctor_args args;
1942 uma_keg_t keg;
1943 uma_zone_t res;
1944 bool locked;
1945
1946 keg = zone_first_keg(master);
1947 memset(&args, 0, sizeof(args));
1948 args.name = name;
1949 args.size = keg->uk_size;
1950 args.ctor = ctor;
1951 args.dtor = dtor;
1952 args.uminit = zinit;
1953 args.fini = zfini;
1954 args.align = keg->uk_align;
1955 args.flags = keg->uk_flags | UMA_ZONE_SECONDARY;
1956 args.keg = keg;
1957
1958 if (booted < UMA_STARTUP2) {
1959 locked = false;
1960 } else {
1961 sx_slock(&uma_drain_lock);
1962 locked = true;
1963 }
1964 /* XXX Attaches only one keg of potentially many. */
1965 res = zone_alloc_item(zones, &args, M_WAITOK);
1966 if (locked)
1967 sx_sunlock(&uma_drain_lock);
1968 return (res);
1969}
1970
1971/* See uma.h */
1972uma_zone_t
1973uma_zcache_create(char *name, int size, uma_ctor ctor, uma_dtor dtor,
1974 uma_init zinit, uma_fini zfini, uma_import zimport,
1975 uma_release zrelease, void *arg, int flags)
1976{
1977 struct uma_zctor_args args;
1978
1979 memset(&args, 0, sizeof(args));
1980 args.name = name;
1981 args.size = size;
1982 args.ctor = ctor;
1983 args.dtor = dtor;
1984 args.uminit = zinit;
1985 args.fini = zfini;
1986 args.import = zimport;
1987 args.release = zrelease;
1988 args.arg = arg;
1989 args.align = 0;
1990 args.flags = flags;
1991
1992 return (zone_alloc_item(zones, &args, M_WAITOK));
1993}
1994
1995static void
1996zone_lock_pair(uma_zone_t a, uma_zone_t b)
1997{
1998 if (a < b) {
1999 ZONE_LOCK(a);
2000 mtx_lock_flags(b->uz_lockptr, MTX_DUPOK);
2001 } else {
2002 ZONE_LOCK(b);
2003 mtx_lock_flags(a->uz_lockptr, MTX_DUPOK);
2004 }
2005}
2006
2007static void
2008zone_unlock_pair(uma_zone_t a, uma_zone_t b)
2009{
2010
2011 ZONE_UNLOCK(a);
2012 ZONE_UNLOCK(b);
2013}
2014
2015int
2016uma_zsecond_add(uma_zone_t zone, uma_zone_t master)
2017{
2018 uma_klink_t klink;
2019 uma_klink_t kl;
2020 int error;
2021
2022 error = 0;
2023 klink = malloc(sizeof(*klink), M_TEMP, M_WAITOK | M_ZERO);
2024
2025 zone_lock_pair(zone, master);
2026 /*
2027 * zone must use vtoslab() to resolve objects and must already be
2028 * a secondary.
2029 */
2030 if ((zone->uz_flags & (UMA_ZONE_VTOSLAB | UMA_ZONE_SECONDARY))
2031 != (UMA_ZONE_VTOSLAB | UMA_ZONE_SECONDARY)) {
2032 error = EINVAL;
2033 goto out;
2034 }
2035 /*
2036 * The new master must also use vtoslab().
2037 */
2038 if ((zone->uz_flags & UMA_ZONE_VTOSLAB) != UMA_ZONE_VTOSLAB) {
2039 error = EINVAL;
2040 goto out;
2041 }
2042
2043 /*
2044 * The underlying object must be the same size. rsize
2045 * may be different.
2046 */
2047 if (master->uz_size != zone->uz_size) {
2048 error = E2BIG;
2049 goto out;
2050 }
2051 /*
2052 * Put it at the end of the list.
2053 */
2054 klink->kl_keg = zone_first_keg(master);
2055 LIST_FOREACH(kl, &zone->uz_kegs, kl_link) {
2056 if (LIST_NEXT(kl, kl_link) == NULL) {
2057 LIST_INSERT_AFTER(kl, klink, kl_link);
2058 break;
2059 }
2060 }
2061 klink = NULL;
2062 zone->uz_flags |= UMA_ZFLAG_MULTI;
2063 zone->uz_slab = zone_fetch_slab_multi;
2064
2065out:
2066 zone_unlock_pair(zone, master);
2067 if (klink != NULL)
2068 free(klink, M_TEMP);
2069
2070 return (error);
2071}
2072
2073
2074/* See uma.h */
2075void
2076uma_zdestroy(uma_zone_t zone)
2077{
2078
2079 sx_slock(&uma_drain_lock);
2080 zone_free_item(zones, zone, NULL, SKIP_NONE);
2081 sx_sunlock(&uma_drain_lock);
2082}
2083
2084/* See uma.h */
2085void *
2086uma_zalloc_arg(uma_zone_t zone, void *udata, int flags)
2087{
2088 void *item;
2089 uma_cache_t cache;
2090 uma_bucket_t bucket;
2091 int lockfail;
2092 int cpu;
2093
2094 /* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
2095 random_harvest_fast_uma(&zone, sizeof(zone), 1, RANDOM_UMA);
2096
2097 /* This is the fast path allocation */
2098#ifdef UMA_DEBUG_ALLOC_1
2099 printf("Allocating one item from %s(%p)\n", zone->uz_name, zone);
2100#endif
2101 CTR3(KTR_UMA, "uma_zalloc_arg thread %x zone %s flags %d", curthread,
2102 zone->uz_name, flags);
2103
2104 if (flags & M_WAITOK) {
2105 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
2106 "uma_zalloc_arg: zone \"%s\"", zone->uz_name);
2107 }
2108 KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
2109 ("uma_zalloc_arg: called with spinlock or critical section held"));
2110
2111#ifdef DEBUG_MEMGUARD
2112 if (memguard_cmp_zone(zone)) {
2113 item = memguard_alloc(zone->uz_size, flags);
2114 if (item != NULL) {
2115 if (zone->uz_init != NULL &&
2116 zone->uz_init(item, zone->uz_size, flags) != 0)
2117 return (NULL);
2118 if (zone->uz_ctor != NULL &&
2119 zone->uz_ctor(item, zone->uz_size, udata,
2120 flags) != 0) {
2121 zone->uz_fini(item, zone->uz_size);
2122 return (NULL);
2123 }
2124 return (item);
2125 }
2126 /* This is unfortunate but should not be fatal. */
2127 }
2128#endif
2129 /*
2130 * If possible, allocate from the per-CPU cache. There are two
2131 * requirements for safe access to the per-CPU cache: (1) the thread
2132 * accessing the cache must not be preempted or yield during access,
2133 * and (2) the thread must not migrate CPUs without switching which
2134 * cache it accesses. We rely on a critical section to prevent
2135 * preemption and migration. We release the critical section in
2136 * order to acquire the zone mutex if we are unable to allocate from
2137 * the current cache; when we re-acquire the critical section, we
2138 * must detect and handle migration if it has occurred.
2139 */
2140 critical_enter();
2141 cpu = curcpu;
2142 cache = &zone->uz_cpu[cpu];
2143
2144zalloc_start:
2145 bucket = cache->uc_allocbucket;
2146 if (bucket != NULL && bucket->ub_cnt > 0) {
2147 bucket->ub_cnt--;
2148 item = bucket->ub_bucket[bucket->ub_cnt];
2149#ifdef INVARIANTS
2150 bucket->ub_bucket[bucket->ub_cnt] = NULL;
2151#endif
2152 KASSERT(item != NULL, ("uma_zalloc: Bucket pointer mangled."));
2153 cache->uc_allocs++;
2154 critical_exit();
2155 if (zone->uz_ctor != NULL &&
2156 zone->uz_ctor(item, zone->uz_size, udata, flags) != 0) {
2157 atomic_add_long(&zone->uz_fails, 1);
2158 zone_free_item(zone, item, udata, SKIP_DTOR);
2159 return (NULL);
2160 }
2161#ifdef INVARIANTS
2162 uma_dbg_alloc(zone, NULL, item);
2163#endif
2164 if (flags & M_ZERO)
2165 uma_zero_item(item, zone);
2166 return (item);
2167 }
2168
2169 /*
2170 * We have run out of items in our alloc bucket.
2171 * See if we can switch with our free bucket.
2172 */
2173 bucket = cache->uc_freebucket;
2174 if (bucket != NULL && bucket->ub_cnt > 0) {
2175#ifdef UMA_DEBUG_ALLOC
2176 printf("uma_zalloc: Swapping empty with alloc.\n");
2177#endif
2178 cache->uc_freebucket = cache->uc_allocbucket;
2179 cache->uc_allocbucket = bucket;
2180 goto zalloc_start;
2181 }
2182
2183 /*
2184 * Discard any empty allocation bucket while we hold no locks.
2185 */
2186 bucket = cache->uc_allocbucket;
2187 cache->uc_allocbucket = NULL;
2188 critical_exit();
2189 if (bucket != NULL)
2190 bucket_free(zone, bucket, udata);
2191
2192 /* Short-circuit for zones without buckets and low memory. */
2193 if (zone->uz_count == 0 || bucketdisable)
2194 goto zalloc_item;
2195
2196 /*
2197 * Attempt to retrieve the item from the per-CPU cache has failed, so
2198 * we must go back to the zone. This requires the zone lock, so we
2199 * must drop the critical section, then re-acquire it when we go back
2200 * to the cache. Since the critical section is released, we may be
2201 * preempted or migrate. As such, make sure not to maintain any
2202 * thread-local state specific to the cache from prior to releasing
2203 * the critical section.
2204 */
2205 lockfail = 0;
2206 if (ZONE_TRYLOCK(zone) == 0) {
2207 /* Record contention to size the buckets. */
2208 ZONE_LOCK(zone);
2209 lockfail = 1;
2210 }
2211 critical_enter();
2212 cpu = curcpu;
2213 cache = &zone->uz_cpu[cpu];
2214
2215 /*
2216 * Since we have locked the zone we may as well send back our stats.
2217 */
2218 atomic_add_long(&zone->uz_allocs, cache->uc_allocs);
2219 atomic_add_long(&zone->uz_frees, cache->uc_frees);
2220 cache->uc_allocs = 0;
2221 cache->uc_frees = 0;
2222
2223 /* See if we lost the race to fill the cache. */
2224 if (cache->uc_allocbucket != NULL) {
2225 ZONE_UNLOCK(zone);
2226 goto zalloc_start;
2227 }
2228
2229 /*
2230 * Check the zone's cache of buckets.
2231 */
2232 if ((bucket = LIST_FIRST(&zone->uz_buckets)) != NULL) {
2233 KASSERT(bucket->ub_cnt != 0,
2234 ("uma_zalloc_arg: Returning an empty bucket."));
2235
2236 LIST_REMOVE(bucket, ub_link);
2237 cache->uc_allocbucket = bucket;
2238 ZONE_UNLOCK(zone);
2239 goto zalloc_start;
2240 }
2241 /* We are no longer associated with this CPU. */
2242 critical_exit();
2243
2244 /*
2245 * We bump the uz count when the cache size is insufficient to
2246 * handle the working set.
2247 */
2248 if (lockfail && zone->uz_count < BUCKET_MAX)
2249 zone->uz_count++;
2250 ZONE_UNLOCK(zone);
2251
2252 /*
2253 * Now lets just fill a bucket and put it on the free list. If that
2254 * works we'll restart the allocation from the beginning and it
2255 * will use the just filled bucket.
2256 */
2257 bucket = zone_alloc_bucket(zone, udata, flags);
2258 if (bucket != NULL) {
2259 ZONE_LOCK(zone);
2260 critical_enter();
2261 cpu = curcpu;
2262 cache = &zone->uz_cpu[cpu];
2263 /*
2264 * See if we lost the race or were migrated. Cache the
2265 * initialized bucket to make this less likely or claim
2266 * the memory directly.
2267 */
2268 if (cache->uc_allocbucket == NULL)
2269 cache->uc_allocbucket = bucket;
2270 else
2271 LIST_INSERT_HEAD(&zone->uz_buckets, bucket, ub_link);
2272 ZONE_UNLOCK(zone);
2273 goto zalloc_start;
2274 }
2275
2276 /*
2277 * We may not be able to get a bucket so return an actual item.
2278 */
2279#ifdef UMA_DEBUG
2280 printf("uma_zalloc_arg: Bucketzone returned NULL\n");
2281#endif
2282
2283zalloc_item:
2284 item = zone_alloc_item(zone, udata, flags);
2285
2286 return (item);
2287}
2288
2289static uma_slab_t
2290keg_fetch_slab(uma_keg_t keg, uma_zone_t zone, int flags)
2291{
2292 uma_slab_t slab;
2293 int reserve;
2294
2295 mtx_assert(&keg->uk_lock, MA_OWNED);
2296 slab = NULL;
2297 reserve = 0;
2298 if ((flags & M_USE_RESERVE) == 0)
2299 reserve = keg->uk_reserve;
2300
2301 for (;;) {
2302 /*
2303 * Find a slab with some space. Prefer slabs that are partially
2304 * used over those that are totally full. This helps to reduce
2305 * fragmentation.
2306 */
2307 if (keg->uk_free > reserve) {
2308 if (!LIST_EMPTY(&keg->uk_part_slab)) {
2309 slab = LIST_FIRST(&keg->uk_part_slab);
2310 } else {
2311 slab = LIST_FIRST(&keg->uk_free_slab);
2312 LIST_REMOVE(slab, us_link);
2313 LIST_INSERT_HEAD(&keg->uk_part_slab, slab,
2314 us_link);
2315 }
2316 MPASS(slab->us_keg == keg);
2317 return (slab);
2318 }
2319
2320 /*
2321 * M_NOVM means don't ask at all!
2322 */
2323 if (flags & M_NOVM)
2324 break;
2325
2326 if (keg->uk_maxpages && keg->uk_pages >= keg->uk_maxpages) {
2327 keg->uk_flags |= UMA_ZFLAG_FULL;
2328 /*
2329 * If this is not a multi-zone, set the FULL bit.
2330 * Otherwise slab_multi() takes care of it.
2331 */
2332 if ((zone->uz_flags & UMA_ZFLAG_MULTI) == 0) {
2333 zone->uz_flags |= UMA_ZFLAG_FULL;
2334 zone_log_warning(zone);
2335 zone_maxaction(zone);
2336 }
2337 if (flags & M_NOWAIT)
2338 break;
2339 zone->uz_sleeps++;
2340 msleep(keg, &keg->uk_lock, PVM, "keglimit", 0);
2341 continue;
2342 }
2343 slab = keg_alloc_slab(keg, zone, flags);
2344 /*
2345 * If we got a slab here it's safe to mark it partially used
2346 * and return. We assume that the caller is going to remove
2347 * at least one item.
2348 */
2349 if (slab) {
2350 MPASS(slab->us_keg == keg);
2351 LIST_INSERT_HEAD(&keg->uk_part_slab, slab, us_link);
2352 return (slab);
2353 }
2354 /*
2355 * We might not have been able to get a slab but another cpu
2356 * could have while we were unlocked. Check again before we
2357 * fail.
2358 */
2359 flags |= M_NOVM;
2360 }
2361 return (slab);
2362}
2363
2364static uma_slab_t
2365zone_fetch_slab(uma_zone_t zone, uma_keg_t keg, int flags)
2366{
2367 uma_slab_t slab;
2368
2369 if (keg == NULL) {
2370 keg = zone_first_keg(zone);
2371 KEG_LOCK(keg);
2372 }
2373
2374 for (;;) {
2375 slab = keg_fetch_slab(keg, zone, flags);
2376 if (slab)
2377 return (slab);
2378 if (flags & (M_NOWAIT | M_NOVM))
2379 break;
2380 }
2381 KEG_UNLOCK(keg);
2382 return (NULL);
2383}
2384
2385/*
2386 * uma_zone_fetch_slab_multi: Fetches a slab from one available keg. Returns
2387 * with the keg locked. On NULL no lock is held.
2388 *
2389 * The last pointer is used to seed the search. It is not required.
2390 */
2391static uma_slab_t
2392zone_fetch_slab_multi(uma_zone_t zone, uma_keg_t last, int rflags)
2393{
2394 uma_klink_t klink;
2395 uma_slab_t slab;
2396 uma_keg_t keg;
2397 int flags;
2398 int empty;
2399 int full;
2400
2401 /*
2402 * Don't wait on the first pass. This will skip limit tests
2403 * as well. We don't want to block if we can find a provider
2404 * without blocking.
2405 */
2406 flags = (rflags & ~M_WAITOK) | M_NOWAIT;
2407 /*
2408 * Use the last slab allocated as a hint for where to start
2409 * the search.
2410 */
2411 if (last != NULL) {
2412 slab = keg_fetch_slab(last, zone, flags);
2413 if (slab)
2414 return (slab);
2415 KEG_UNLOCK(last);
2416 }
2417 /*
2418 * Loop until we have a slab incase of transient failures
2419 * while M_WAITOK is specified. I'm not sure this is 100%
2420 * required but we've done it for so long now.
2421 */
2422 for (;;) {
2423 empty = 0;
2424 full = 0;
2425 /*
2426 * Search the available kegs for slabs. Be careful to hold the
2427 * correct lock while calling into the keg layer.
2428 */
2429 LIST_FOREACH(klink, &zone->uz_kegs, kl_link) {
2430 keg = klink->kl_keg;
2431 KEG_LOCK(keg);
2432 if ((keg->uk_flags & UMA_ZFLAG_FULL) == 0) {
2433 slab = keg_fetch_slab(keg, zone, flags);
2434 if (slab)
2435 return (slab);
2436 }
2437 if (keg->uk_flags & UMA_ZFLAG_FULL)
2438 full++;
2439 else
2440 empty++;
2441 KEG_UNLOCK(keg);
2442 }
2443 if (rflags & (M_NOWAIT | M_NOVM))
2444 break;
2445 flags = rflags;
2446 /*
2447 * All kegs are full. XXX We can't atomically check all kegs
2448 * and sleep so just sleep for a short period and retry.
2449 */
2450 if (full && !empty) {
2451 ZONE_LOCK(zone);
2452 zone->uz_flags |= UMA_ZFLAG_FULL;
2453 zone->uz_sleeps++;
2454 zone_log_warning(zone);
2455 zone_maxaction(zone);
2456 msleep(zone, zone->uz_lockptr, PVM,
2457 "zonelimit", hz/100);
2458 zone->uz_flags &= ~UMA_ZFLAG_FULL;
2459 ZONE_UNLOCK(zone);
2460 continue;
2461 }
2462 }
2463 return (NULL);
2464}
2465
2466static void *
2467slab_alloc_item(uma_keg_t keg, uma_slab_t slab)
2468{
2469 void *item;
2470 uint8_t freei;
2471
2472 MPASS(keg == slab->us_keg);
2473 mtx_assert(&keg->uk_lock, MA_OWNED);
2474
2475 freei = BIT_FFS(SLAB_SETSIZE, &slab->us_free) - 1;
2476 BIT_CLR(SLAB_SETSIZE, freei, &slab->us_free);
2477 item = slab->us_data + (keg->uk_rsize * freei);
2478 slab->us_freecount--;
2479 keg->uk_free--;
2480
2481 /* Move this slab to the full list */
2482 if (slab->us_freecount == 0) {
2483 LIST_REMOVE(slab, us_link);
2484 LIST_INSERT_HEAD(&keg->uk_full_slab, slab, us_link);
2485 }
2486
2487 return (item);
2488}
2489
2490static int
2491zone_import(uma_zone_t zone, void **bucket, int max, int flags)
2492{
2493 uma_slab_t slab;
2494 uma_keg_t keg;
2495 int i;
2496
2497 slab = NULL;
2498 keg = NULL;
2499 /* Try to keep the buckets totally full */
2500 for (i = 0; i < max; ) {
2501 if ((slab = zone->uz_slab(zone, keg, flags)) == NULL)
2502 break;
2503 keg = slab->us_keg;
2504 while (slab->us_freecount && i < max) {
2505 bucket[i++] = slab_alloc_item(keg, slab);
2506 if (keg->uk_free <= keg->uk_reserve)
2507 break;
2508 }
2509 /* Don't grab more than one slab at a time. */
2510 flags &= ~M_WAITOK;
2511 flags |= M_NOWAIT;
2512 }
2513 if (slab != NULL)
2514 KEG_UNLOCK(keg);
2515
2516 return i;
2517}
2518
2519static uma_bucket_t
2520zone_alloc_bucket(uma_zone_t zone, void *udata, int flags)
2521{
2522 uma_bucket_t bucket;
2523 int max;
2524
2525 /* Don't wait for buckets, preserve caller's NOVM setting. */
2526 bucket = bucket_alloc(zone, udata, M_NOWAIT | (flags & M_NOVM));
2527 if (bucket == NULL)
2528 return (NULL);
2529
2530 max = MIN(bucket->ub_entries, zone->uz_count);
2531 bucket->ub_cnt = zone->uz_import(zone->uz_arg, bucket->ub_bucket,
2532 max, flags);
2533
2534 /*
2535 * Initialize the memory if necessary.
2536 */
2537 if (bucket->ub_cnt != 0 && zone->uz_init != NULL) {
2538 int i;
2539
2540 for (i = 0; i < bucket->ub_cnt; i++)
2541 if (zone->uz_init(bucket->ub_bucket[i], zone->uz_size,
2542 flags) != 0)
2543 break;
2544 /*
2545 * If we couldn't initialize the whole bucket, put the
2546 * rest back onto the freelist.
2547 */
2548 if (i != bucket->ub_cnt) {
2549 zone->uz_release(zone->uz_arg, &bucket->ub_bucket[i],
2550 bucket->ub_cnt - i);
2551#ifdef INVARIANTS
2552 bzero(&bucket->ub_bucket[i],
2553 sizeof(void *) * (bucket->ub_cnt - i));
2554#endif
2555 bucket->ub_cnt = i;
2556 }
2557 }
2558
2559 if (bucket->ub_cnt == 0) {
2560 bucket_free(zone, bucket, udata);
2561 atomic_add_long(&zone->uz_fails, 1);
2562 return (NULL);
2563 }
2564
2565 return (bucket);
2566}
2567
2568/*
2569 * Allocates a single item from a zone.
2570 *
2571 * Arguments
2572 * zone The zone to alloc for.
2573 * udata The data to be passed to the constructor.
2574 * flags M_WAITOK, M_NOWAIT, M_ZERO.
2575 *
2576 * Returns
2577 * NULL if there is no memory and M_NOWAIT is set
2578 * An item if successful
2579 */
2580
2581static void *
2582zone_alloc_item(uma_zone_t zone, void *udata, int flags)
2583{
2584 void *item;
2585
2586 item = NULL;
2587
2588#ifdef UMA_DEBUG_ALLOC
2589 printf("INTERNAL: Allocating one item from %s(%p)\n", zone->uz_name, zone);
2590#endif
2591 if (zone->uz_import(zone->uz_arg, &item, 1, flags) != 1)
2592 goto fail;
2593 atomic_add_long(&zone->uz_allocs, 1);
2594
2595 /*
2596 * We have to call both the zone's init (not the keg's init)
2597 * and the zone's ctor. This is because the item is going from
2598 * a keg slab directly to the user, and the user is expecting it
2599 * to be both zone-init'd as well as zone-ctor'd.
2600 */
2601 if (zone->uz_init != NULL) {
2602 if (zone->uz_init(item, zone->uz_size, flags) != 0) {
2603 zone_free_item(zone, item, udata, SKIP_FINI);
2604 goto fail;
2605 }
2606 }
2607 if (zone->uz_ctor != NULL) {
2608 if (zone->uz_ctor(item, zone->uz_size, udata, flags) != 0) {
2609 zone_free_item(zone, item, udata, SKIP_DTOR);
2610 goto fail;
2611 }
2612 }
2613#ifdef INVARIANTS
2614 uma_dbg_alloc(zone, NULL, item);
2615#endif
2616 if (flags & M_ZERO)
2617 uma_zero_item(item, zone);
2618
2619 return (item);
2620
2621fail:
2622 atomic_add_long(&zone->uz_fails, 1);
2623 return (NULL);
2624}
2625
2626/* See uma.h */
2627void
2628uma_zfree_arg(uma_zone_t zone, void *item, void *udata)
2629{
2630 uma_cache_t cache;
2631 uma_bucket_t bucket;
2632 int lockfail;
2633 int cpu;
2634
2635 /* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
2636 random_harvest_fast_uma(&zone, sizeof(zone), 1, RANDOM_UMA);
2637
2638#ifdef UMA_DEBUG_ALLOC_1
2639 printf("Freeing item %p to %s(%p)\n", item, zone->uz_name, zone);
2640#endif
2641 CTR2(KTR_UMA, "uma_zfree_arg thread %x zone %s", curthread,
2642 zone->uz_name);
2643
2644 KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
2645 ("uma_zfree_arg: called with spinlock or critical section held"));
2646
2647 /* uma_zfree(..., NULL) does nothing, to match free(9). */
2648 if (item == NULL)
2649 return;
2650#ifdef DEBUG_MEMGUARD
2651 if (is_memguard_addr(item)) {
2652 if (zone->uz_dtor != NULL)
2653 zone->uz_dtor(item, zone->uz_size, udata);
2654 if (zone->uz_fini != NULL)
2655 zone->uz_fini(item, zone->uz_size);
2656 memguard_free(item);
2657 return;
2658 }
2659#endif
2660#ifdef INVARIANTS
2661 if (zone->uz_flags & UMA_ZONE_MALLOC)
2662 uma_dbg_free(zone, udata, item);
2663 else
2664 uma_dbg_free(zone, NULL, item);
2665#endif
2666 if (zone->uz_dtor != NULL)
2667 zone->uz_dtor(item, zone->uz_size, udata);
2668
2669 /*
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.
2672 */
2673 if (zone->uz_flags & UMA_ZFLAG_FULL)
2674 goto zfree_item;
2675
2676 /*
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.
2686 */
2687zfree_restart:
2688 critical_enter();
2689 cpu = curcpu;
2690 cache = &zone->uz_cpu[cpu];
2691
2692zfree_start:
2693 /*
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.
2697 */
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;
2705 bucket->ub_cnt++;
2706 cache->uc_frees++;
2707 critical_exit();
2708 return;
2709 }
2710
2711 /*
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.
2718 */
2719 critical_exit();
2720 if (zone->uz_count == 0 || bucketdisable)
2721 goto zfree_item;
2722
2723 lockfail = 0;
2724 if (ZONE_TRYLOCK(zone) == 0) {
2725 /* Record contention to size the buckets. */
2726 ZONE_LOCK(zone);
2727 lockfail = 1;
2728 }
2729 critical_enter();
2730 cpu = curcpu;
2731 cache = &zone->uz_cpu[cpu];
2732
2733 /*
2734 * Since we have locked the zone we may as well send back our stats.
2735 */
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;
2740
2741 bucket = cache->uc_freebucket;
2742 if (bucket != NULL && bucket->ub_cnt < bucket->ub_entries) {
2743 ZONE_UNLOCK(zone);
2744 goto zfree_start;
2745 }
2746 cache->uc_freebucket = NULL;
2747
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");
2752#endif
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);
2757 }
2758
2759 /* We are no longer associated with this CPU. */
2760 critical_exit();
2761
2762 /*
2763 * We bump the uz count when the cache size is insufficient to
2764 * handle the working set.
2765 */
2766 if (lockfail && zone->uz_count < BUCKET_MAX)
2767 zone->uz_count++;
2768 ZONE_UNLOCK(zone);
2769
2770#ifdef UMA_DEBUG_ALLOC
2771 printf("uma_zfree: Allocating new free bucket.\n");
2772#endif
2773 bucket = bucket_alloc(zone, udata, M_NOWAIT);
2774 if (bucket) {
2775 critical_enter();
2776 cpu = curcpu;
2777 cache = &zone->uz_cpu[cpu];
2778 if (cache->uc_freebucket == NULL) {
2779 cache->uc_freebucket = bucket;
2780 goto zfree_start;
2781 }
2782 /*
2783 * We lost the race, start over. We have to drop our
2784 * critical section to free the bucket.
2785 */
2786 critical_exit();
2787 bucket_free(zone, bucket, udata);
2788 goto zfree_restart;
2789 }
2790
2791 /*
2792 * If nothing else caught this, we'll just do an internal free.
2793 */
2794zfree_item:
2795 zone_free_item(zone, item, udata, SKIP_DTOR);
2796
2797 return;
2798}
2799
2800static void
2801slab_free_item(uma_keg_t keg, uma_slab_t slab, void *item)
2802{
2803 uint8_t freei;
2804
2805 mtx_assert(&keg->uk_lock, MA_OWNED);
2806 MPASS(keg == slab->us_keg);
2807
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);
2815 }
2816
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++;
2821
2822 /* Keg statistics. */
2823 keg->uk_free++;
2824}
2825
2826static void
2827zone_release(uma_zone_t zone, void **bucket, int cnt)
2828{
2829 void *item;
2830 uma_slab_t slab;
2831 uma_keg_t keg;
2832 uint8_t *mem;
2833 int clearfull;
2834 int i;
2835
2836 clearfull = 0;
2837 keg = zone_first_keg(zone);
2838 KEG_LOCK(keg);
2839 for (i = 0; i < cnt; i++) {
2840 item = bucket[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);
2845 } else {
2846 mem += keg->uk_pgoff;
2847 slab = (uma_slab_t)mem;
2848 }
2849 } else {
2850 slab = vtoslab((vm_offset_t)item);
2851 if (slab->us_keg != keg) {
2852 KEG_UNLOCK(keg);
2853 keg = slab->us_keg;
2854 KEG_LOCK(keg);
2855 }
2856 }
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;
2861 clearfull = 1;
2862 }
2863
2864 /*
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
2869 * threads etc).
2870 */
2871 wakeup(keg);
2872 }
2873 }
2874 KEG_UNLOCK(keg);
2875 if (clearfull) {
2876 ZONE_LOCK(zone);
2877 zone->uz_flags &= ~UMA_ZFLAG_FULL;
2878 wakeup(zone);
2879 ZONE_UNLOCK(zone);
2880 }
2881
2882}
2883
2884/*
2885 * Frees a single item to any zone.
2886 *
2887 * Arguments:
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
2892 */
2893static void
2894zone_free_item(uma_zone_t zone, void *item, void *udata, enum zfreeskip skip)
2895{
2896
2897#ifdef INVARIANTS
2898 if (skip == SKIP_NONE) {
2899 if (zone->uz_flags & UMA_ZONE_MALLOC)
2900 uma_dbg_free(zone, udata, item);
2901 else
2902 uma_dbg_free(zone, NULL, item);
2903 }
2904#endif
2905 if (skip < SKIP_DTOR && zone->uz_dtor)
2906 zone->uz_dtor(item, zone->uz_size, udata);
2907
2908 if (skip < SKIP_FINI && zone->uz_fini)
2909 zone->uz_fini(item, zone->uz_size);
2910
2911 atomic_add_long(&zone->uz_frees, 1);
2912 zone->uz_release(zone->uz_arg, &item, 1);
2913}
2914
2915/* See uma.h */
2916int
2917uma_zone_set_max(uma_zone_t zone, int nitems)
2918{
2919 uma_keg_t keg;
2920
2921 keg = zone_first_keg(zone);
2922 if (keg == NULL)
2923 return (0);
2924 KEG_LOCK(keg);
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;
2929 KEG_UNLOCK(keg);
2930
2931 return (nitems);
2932}
2933
2934/* See uma.h */
2935int
2936uma_zone_get_max(uma_zone_t zone)
2937{
2938 int nitems;
2939 uma_keg_t keg;
2940
2941 keg = zone_first_keg(zone);
2942 if (keg == NULL)
2943 return (0);
2944 KEG_LOCK(keg);
2945 nitems = keg->uk_maxpages * keg->uk_ipers;
2946 KEG_UNLOCK(keg);
2947
2948 return (nitems);
2949}
2950
2951/* See uma.h */
2952void
2953uma_zone_set_warning(uma_zone_t zone, const char *warning)
2954{
2955
2956 ZONE_LOCK(zone);
2957 zone->uz_warning = warning;
2958 ZONE_UNLOCK(zone);
2959}
2960
2961/* See uma.h */
2962void
2963uma_zone_set_maxaction(uma_zone_t zone, uma_maxaction_t maxaction)
2964{
2965
2966 ZONE_LOCK(zone);
2967 TASK_INIT(&zone->uz_maxaction, 0, (task_fn_t *)maxaction, zone);
2968 ZONE_UNLOCK(zone);
2969}
2970
2971/* See uma.h */
2972int
2973uma_zone_get_cur(uma_zone_t zone)
2974{
2975 int64_t nitems;
2976 u_int i;
2977
2978 ZONE_LOCK(zone);
2979 nitems = zone->uz_allocs - zone->uz_frees;
2980 CPU_FOREACH(i) {
2981 /*
2982 * See the comment in sysctl_vm_zone_stats() regarding the
2983 * safety of accessing the per-cpu caches. With the zone lock
2984 * held, it is safe, but can potentially result in stale data.
2985 */
2986 nitems += zone->uz_cpu[i].uc_allocs -
2987 zone->uz_cpu[i].uc_frees;
2988 }
2989 ZONE_UNLOCK(zone);
2990
2991 return (nitems < 0 ? 0 : nitems);
2992}
2993
2994/* See uma.h */
2995void
2996uma_zone_set_init(uma_zone_t zone, uma_init uminit)
2997{
2998 uma_keg_t keg;
2999
3000 keg = zone_first_keg(zone);
3001 KASSERT(keg != NULL, ("uma_zone_set_init: Invalid zone type"));
3002 KEG_LOCK(keg);
3003 KASSERT(keg->uk_pages == 0,
3004 ("uma_zone_set_init on non-empty keg"));
3005 keg->uk_init = uminit;
3006 KEG_UNLOCK(keg);
3007}
3008
3009/* See uma.h */
3010void
3011uma_zone_set_fini(uma_zone_t zone, uma_fini fini)
3012{
3013 uma_keg_t keg;
3014
3015 keg = zone_first_keg(zone);
3016 KASSERT(keg != NULL, ("uma_zone_set_fini: Invalid zone type"));
3017 KEG_LOCK(keg);
3018 KASSERT(keg->uk_pages == 0,
3019 ("uma_zone_set_fini on non-empty keg"));
3020 keg->uk_fini = fini;
3021 KEG_UNLOCK(keg);
3022}
3023
3024/* See uma.h */
3025void
3026uma_zone_set_zinit(uma_zone_t zone, uma_init zinit)
3027{
3028
3029 ZONE_LOCK(zone);
3030 KASSERT(zone_first_keg(zone)->uk_pages == 0,
3031 ("uma_zone_set_zinit on non-empty keg"));
3032 zone->uz_init = zinit;
3033 ZONE_UNLOCK(zone);
3034}
3035
3036/* See uma.h */
3037void
3038uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini)
3039{
3040
3041 ZONE_LOCK(zone);
3042 KASSERT(zone_first_keg(zone)->uk_pages == 0,
3043 ("uma_zone_set_zfini on non-empty keg"));
3044 zone->uz_fini = zfini;
3045 ZONE_UNLOCK(zone);
3046}
3047
3048/* See uma.h */
3049/* XXX uk_freef is not actually used with the zone locked */
3050void
3051uma_zone_set_freef(uma_zone_t zone, uma_free freef)
3052{
3053 uma_keg_t keg;
3054
3055 keg = zone_first_keg(zone);
3056 KASSERT(keg != NULL, ("uma_zone_set_freef: Invalid zone type"));
3057 KEG_LOCK(keg);
3058 keg->uk_freef = freef;
3059 KEG_UNLOCK(keg);
3060}
3061
3062/* See uma.h */
3063/* XXX uk_allocf is not actually used with the zone locked */
3064void
3065uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf)
3066{
3067 uma_keg_t keg;
3068
3069 keg = zone_first_keg(zone);
3070 KEG_LOCK(keg);
3071 keg->uk_allocf = allocf;
3072 KEG_UNLOCK(keg);
3073}
3074
3075/* See uma.h */
3076void
3077uma_zone_reserve(uma_zone_t zone, int items)
3078{
3079 uma_keg_t keg;
3080
3081 keg = zone_first_keg(zone);
3082 if (keg == NULL)
3083 return;
3084 KEG_LOCK(keg);
3085 keg->uk_reserve = items;
3086 KEG_UNLOCK(keg);
3087
3088 return;
3089}
3090
3091/* See uma.h */
3092int
3093uma_zone_reserve_kva(uma_zone_t zone, int count)
3094{
3095 uma_keg_t keg;
3096 vm_offset_t kva;
3097 u_int pages;
3098
3099 keg = zone_first_keg(zone);
3100 if (keg == NULL)
3101 return (0);
3102 pages = count / keg->uk_ipers;
3103
3104 if (pages * keg->uk_ipers < count)
3105 pages++;
3106
3107#ifdef UMA_MD_SMALL_ALLOC
3108 if (keg->uk_ppera > 1) {
3109#else
3110 if (1) {
3111#endif
3112 kva = kva_alloc((vm_size_t)pages * UMA_SLAB_SIZE);
3113 if (kva == 0)
3114 return (0);
3115 } else
3116 kva = 0;
3117 KEG_LOCK(keg);
3118 keg->uk_kva = kva;
3119 keg->uk_offset = 0;
3120 keg->uk_maxpages = pages;
3121#ifdef UMA_MD_SMALL_ALLOC
3122 keg->uk_allocf = (keg->uk_ppera > 1) ? noobj_alloc : uma_small_alloc;
3123#else
3124 keg->uk_allocf = noobj_alloc;
3125#endif
3126 keg->uk_flags |= UMA_ZONE_NOFREE;
3127 KEG_UNLOCK(keg);
3128
3129 return (1);
3130}
3131
3132/* See uma.h */
3133void
3134uma_prealloc(uma_zone_t zone, int items)
3135{
3136 int slabs;
3137 uma_slab_t slab;
3138 uma_keg_t keg;
3139
3140 keg = zone_first_keg(zone);
3141 if (keg == NULL)
3142 return;
3143 KEG_LOCK(keg);
3144 slabs = items / keg->uk_ipers;
3145 if (slabs * keg->uk_ipers < items)
3146 slabs++;
3147 while (slabs > 0) {
3148 slab = keg_alloc_slab(keg, zone, M_WAITOK);
3149 if (slab == NULL)
3150 break;
3151 MPASS(slab->us_keg == keg);
3152 LIST_INSERT_HEAD(&keg->uk_free_slab, slab, us_link);
3153 slabs--;
3154 }
3155 KEG_UNLOCK(keg);
3156}
3157
3158/* See uma.h */
3159static void
3160uma_reclaim_locked(bool kmem_danger)
3161{
3162
3163#ifdef UMA_DEBUG
3164 printf("UMA: vm asked us to release pages!\n");
3165#endif
3166 sx_assert(&uma_drain_lock, SA_XLOCKED);
3167 bucket_enable();
3168 zone_foreach(zone_drain);
3169 if (vm_page_count_min() || kmem_danger) {
3170 cache_drain_safe(NULL);
3171 zone_foreach(zone_drain);
3172 }
3173 /*
3174 * Some slabs may have been freed but this zone will be visited early
3175 * we visit again so that we can free pages that are empty once other
3176 * zones are drained. We have to do the same for buckets.
3177 */
3178 zone_drain(slabzone);
3179 bucket_zone_drain();
3180}
3181
3182void
3183uma_reclaim(void)
3184{
3185
3186 sx_xlock(&uma_drain_lock);
3187 uma_reclaim_locked(false);
3188 sx_xunlock(&uma_drain_lock);
3189}
3190
3191static int uma_reclaim_needed;
3192
3193void
3194uma_reclaim_wakeup(void)
3195{
3196
3197 uma_reclaim_needed = 1;
3198 wakeup(&uma_reclaim_needed);
3199}
3200
3201void
3202uma_reclaim_worker(void *arg __unused)
3203{
3204
3205 sx_xlock(&uma_drain_lock);
3206 for (;;) {
3207 sx_sleep(&uma_reclaim_needed, &uma_drain_lock, PVM,
3208 "umarcl", 0);
3209 if (uma_reclaim_needed) {
3210 uma_reclaim_needed = 0;
3211 uma_reclaim_locked(true);
3212 }
3213 }
3214}
3215
3216/* See uma.h */
3217int
3218uma_zone_exhausted(uma_zone_t zone)
3219{
3220 int full;
3221
3222 ZONE_LOCK(zone);
3223 full = (zone->uz_flags & UMA_ZFLAG_FULL);
3224 ZONE_UNLOCK(zone);
3225 return (full);
3226}
3227
3228int
3229uma_zone_exhausted_nolock(uma_zone_t zone)
3230{
3231 return (zone->uz_flags & UMA_ZFLAG_FULL);
3232}
3233
3234void *
3235uma_large_malloc(vm_size_t size, int wait)
3236{
3237 void *mem;
3238 uma_slab_t slab;
3239 uint8_t flags;
3240
3241 slab = zone_alloc_item(slabzone, NULL, wait);
3242 if (slab == NULL)
3243 return (NULL);
3244 mem = page_alloc(NULL, size, &flags, wait);
3245 if (mem) {
3246 vsetslab((vm_offset_t)mem, slab);
3247 slab->us_data = mem;
3248 slab->us_flags = flags | UMA_SLAB_MALLOC;
3249 slab->us_size = size;
3250 } else {
3251 zone_free_item(slabzone, slab, NULL, SKIP_NONE);
3252 }
3253
3254 return (mem);
3255}
3256
3257void
3258uma_large_free(uma_slab_t slab)
3259{
3260
3261 page_free(slab->us_data, slab->us_size, slab->us_flags);
3262 zone_free_item(slabzone, slab, NULL, SKIP_NONE);
3263}
3264
3265static void
3266uma_zero_item(void *item, uma_zone_t zone)
3267{
3268 int i;
3269
3270 if (zone->uz_flags & UMA_ZONE_PCPU) {
3271 CPU_FOREACH(i)
3272 bzero(zpcpu_get_cpu(item, i), zone->uz_size);
3273 } else
3274 bzero(item, zone->uz_size);
3275}
3276
3277void
3278uma_print_stats(void)
3279{
3280 zone_foreach(uma_print_zone);
3281}
3282
3283static void
3284slab_print(uma_slab_t slab)
3285{
3286 printf("slab: keg %p, data %p, freecount %d\n",
3287 slab->us_keg, slab->us_data, slab->us_freecount);
3288}
3289
3290static void
3291cache_print(uma_cache_t cache)
3292{
3293 printf("alloc: %p(%d), free: %p(%d)\n",
3294 cache->uc_allocbucket,
3295 cache->uc_allocbucket?cache->uc_allocbucket->ub_cnt:0,
3296 cache->uc_freebucket,
3297 cache->uc_freebucket?cache->uc_freebucket->ub_cnt:0);
3298}
3299
3300static void
3301uma_print_keg(uma_keg_t keg)
3302{
3303 uma_slab_t slab;
3304
3305 printf("keg: %s(%p) size %d(%d) flags %#x ipers %d ppera %d "
3306 "out %d free %d limit %d\n",
3307 keg->uk_name, keg, keg->uk_size, keg->uk_rsize, keg->uk_flags,
3308 keg->uk_ipers, keg->uk_ppera,
3309 (keg->uk_ipers * keg->uk_pages) - keg->uk_free, keg->uk_free,
3310 (keg->uk_maxpages / keg->uk_ppera) * keg->uk_ipers);
3311 printf("Part slabs:\n");
3312 LIST_FOREACH(slab, &keg->uk_part_slab, us_link)
3313 slab_print(slab);
3314 printf("Free slabs:\n");
3315 LIST_FOREACH(slab, &keg->uk_free_slab, us_link)
3316 slab_print(slab);
3317 printf("Full slabs:\n");
3318 LIST_FOREACH(slab, &keg->uk_full_slab, us_link)
3319 slab_print(slab);
3320}
3321
3322void
3323uma_print_zone(uma_zone_t zone)
3324{
3325 uma_cache_t cache;
3326 uma_klink_t kl;
3327 int i;
3328
3329 printf("zone: %s(%p) size %d flags %#x\n",
3330 zone->uz_name, zone, zone->uz_size, zone->uz_flags);
3331 LIST_FOREACH(kl, &zone->uz_kegs, kl_link)
3332 uma_print_keg(kl->kl_keg);
3333 CPU_FOREACH(i) {
3334 cache = &zone->uz_cpu[i];
3335 printf("CPU %d Cache:\n", i);
3336 cache_print(cache);
3337 }
3338}
3339
3340#ifdef DDB
3341/*
3342 * Generate statistics across both the zone and its per-cpu cache's. Return
3343 * desired statistics if the pointer is non-NULL for that statistic.
3344 *
3345 * Note: does not update the zone statistics, as it can't safely clear the
3346 * per-CPU cache statistic.
3347 *
3348 * XXXRW: Following the uc_allocbucket and uc_freebucket pointers here isn't
3349 * safe from off-CPU; we should modify the caches to track this information
3350 * directly so that we don't have to.
3351 */
3352static void
3353uma_zone_sumstat(uma_zone_t z, int *cachefreep, uint64_t *allocsp,
3354 uint64_t *freesp, uint64_t *sleepsp)
3355{
3356 uma_cache_t cache;
3357 uint64_t allocs, frees, sleeps;
3358 int cachefree, cpu;
3359
3360 allocs = frees = sleeps = 0;
3361 cachefree = 0;
3362 CPU_FOREACH(cpu) {
3363 cache = &z->uz_cpu[cpu];
3364 if (cache->uc_allocbucket != NULL)
3365 cachefree += cache->uc_allocbucket->ub_cnt;
3366 if (cache->uc_freebucket != NULL)
3367 cachefree += cache->uc_freebucket->ub_cnt;
3368 allocs += cache->uc_allocs;
3369 frees += cache->uc_frees;
3370 }
3371 allocs += z->uz_allocs;
3372 frees += z->uz_frees;
3373 sleeps += z->uz_sleeps;
3374 if (cachefreep != NULL)
3375 *cachefreep = cachefree;
3376 if (allocsp != NULL)
3377 *allocsp = allocs;
3378 if (freesp != NULL)
3379 *freesp = frees;
3380 if (sleepsp != NULL)
3381 *sleepsp = sleeps;
3382}
3383#endif /* DDB */
3384
3385static int
3386sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS)
3387{
3388 uma_keg_t kz;
3389 uma_zone_t z;
3390 int count;
3391
3392 count = 0;
3393 rw_rlock(&uma_rwlock);
3394 LIST_FOREACH(kz, &uma_kegs, uk_link) {
3395 LIST_FOREACH(z, &kz->uk_zones, uz_link)
3396 count++;
3397 }
3398 rw_runlock(&uma_rwlock);
3399 return (sysctl_handle_int(oidp, &count, 0, req));
3400}
3401
3402static int
3403sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS)
3404{
3405 struct uma_stream_header ush;
3406 struct uma_type_header uth;
3407 struct uma_percpu_stat ups;
3408 uma_bucket_t bucket;
3409 struct sbuf sbuf;
3410 uma_cache_t cache;
3411 uma_klink_t kl;
3412 uma_keg_t kz;
3413 uma_zone_t z;
3414 uma_keg_t k;
3415 int count, error, i;
3416
3417 error = sysctl_wire_old_buffer(req, 0);
3418 if (error != 0)
3419 return (error);
3420 sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
3421 sbuf_clear_flags(&sbuf, SBUF_INCLUDENUL);
3422
3423 count = 0;
3424 rw_rlock(&uma_rwlock);
3425 LIST_FOREACH(kz, &uma_kegs, uk_link) {
3426 LIST_FOREACH(z, &kz->uk_zones, uz_link)
3427 count++;
3428 }
3429
3430 /*
3431 * Insert stream header.
3432 */
3433 bzero(&ush, sizeof(ush));
3434 ush.ush_version = UMA_STREAM_VERSION;
3435 ush.ush_maxcpus = (mp_maxid + 1);
3436 ush.ush_count = count;
3437 (void)sbuf_bcat(&sbuf, &ush, sizeof(ush));
3438
3439 LIST_FOREACH(kz, &uma_kegs, uk_link) {
3440 LIST_FOREACH(z, &kz->uk_zones, uz_link) {
3441 bzero(&uth, sizeof(uth));
3442 ZONE_LOCK(z);
3443 strlcpy(uth.uth_name, z->uz_name, UTH_MAX_NAME);
3444 uth.uth_align = kz->uk_align;
3445 uth.uth_size = kz->uk_size;
3446 uth.uth_rsize = kz->uk_rsize;
3447 LIST_FOREACH(kl, &z->uz_kegs, kl_link) {
3448 k = kl->kl_keg;
3449 uth.uth_maxpages += k->uk_maxpages;
3450 uth.uth_pages += k->uk_pages;
3451 uth.uth_keg_free += k->uk_free;
3452 uth.uth_limit = (k->uk_maxpages / k->uk_ppera)
3453 * k->uk_ipers;
3454 }
3455
3456 /*
3457 * A zone is secondary is it is not the first entry
3458 * on the keg's zone list.
3459 */
3460 if ((z->uz_flags & UMA_ZONE_SECONDARY) &&
3461 (LIST_FIRST(&kz->uk_zones) != z))
3462 uth.uth_zone_flags = UTH_ZONE_SECONDARY;
3463
3464 LIST_FOREACH(bucket, &z->uz_buckets, ub_link)
3465 uth.uth_zone_free += bucket->ub_cnt;
3466 uth.uth_allocs = z->uz_allocs;
3467 uth.uth_frees = z->uz_frees;
3468 uth.uth_fails = z->uz_fails;
3469 uth.uth_sleeps = z->uz_sleeps;
3470 (void)sbuf_bcat(&sbuf, &uth, sizeof(uth));
3471 /*
3472 * While it is not normally safe to access the cache
3473 * bucket pointers while not on the CPU that owns the
3474 * cache, we only allow the pointers to be exchanged
3475 * without the zone lock held, not invalidated, so
3476 * accept the possible race associated with bucket
3477 * exchange during monitoring.
3478 */
3479 for (i = 0; i < (mp_maxid + 1); i++) {
3480 bzero(&ups, sizeof(ups));
3481 if (kz->uk_flags & UMA_ZFLAG_INTERNAL)
3482 goto skip;
3483 if (CPU_ABSENT(i))
3484 goto skip;
3485 cache = &z->uz_cpu[i];
3486 if (cache->uc_allocbucket != NULL)
3487 ups.ups_cache_free +=
3488 cache->uc_allocbucket->ub_cnt;
3489 if (cache->uc_freebucket != NULL)
3490 ups.ups_cache_free +=
3491 cache->uc_freebucket->ub_cnt;
3492 ups.ups_allocs = cache->uc_allocs;
3493 ups.ups_frees = cache->uc_frees;
3494skip:
3495 (void)sbuf_bcat(&sbuf, &ups, sizeof(ups));
3496 }
3497 ZONE_UNLOCK(z);
3498 }
3499 }
3500 rw_runlock(&uma_rwlock);
3501 error = sbuf_finish(&sbuf);
3502 sbuf_delete(&sbuf);
3503 return (error);
3504}
3505
3506int
3507sysctl_handle_uma_zone_max(SYSCTL_HANDLER_ARGS)
3508{
3509 uma_zone_t zone = *(uma_zone_t *)arg1;
3510 int error, max;
3511
3512 max = uma_zone_get_max(zone);
3513 error = sysctl_handle_int(oidp, &max, 0, req);
3514 if (error || !req->newptr)
3515 return (error);
3516
3517 uma_zone_set_max(zone, max);
3518
3519 return (0);
3520}
3521
3522int
3523sysctl_handle_uma_zone_cur(SYSCTL_HANDLER_ARGS)
3524{
3525 uma_zone_t zone = *(uma_zone_t *)arg1;
3526 int cur;
3527
3528 cur = uma_zone_get_cur(zone);
3529 return (sysctl_handle_int(oidp, &cur, 0, req));
3530}
3531
3532#ifdef INVARIANTS
3533static uma_slab_t
3534uma_dbg_getslab(uma_zone_t zone, void *item)
3535{
3536 uma_slab_t slab;
3537 uma_keg_t keg;
3538 uint8_t *mem;
3539
3540 mem = (uint8_t *)((uintptr_t)item & (~UMA_SLAB_MASK));
3541 if (zone->uz_flags & UMA_ZONE_VTOSLAB) {
3542 slab = vtoslab((vm_offset_t)mem);
3543 } else {
3544 /*
3545 * It is safe to return the slab here even though the
3546 * zone is unlocked because the item's allocation state
3547 * essentially holds a reference.
3548 */
3549 ZONE_LOCK(zone);
3550 keg = LIST_FIRST(&zone->uz_kegs)->kl_keg;
3551 if (keg->uk_flags & UMA_ZONE_HASH)
3552 slab = hash_sfind(&keg->uk_hash, mem);
3553 else
3554 slab = (uma_slab_t)(mem + keg->uk_pgoff);
3555 ZONE_UNLOCK(zone);
3556 }
3557
3558 return (slab);
3559}
3560
3561/*
3562 * Set up the slab's freei data such that uma_dbg_free can function.
3563 *
3564 */
3565static void
3566uma_dbg_alloc(uma_zone_t zone, uma_slab_t slab, void *item)
3567{
3568 uma_keg_t keg;
3569 int freei;
3570
3571 if (zone_first_keg(zone) == NULL)
3572 return;
3573 if (slab == NULL) {
3574 slab = uma_dbg_getslab(zone, item);
3575 if (slab == NULL)
3576 panic("uma: item %p did not belong to zone %s\n",
3577 item, zone->uz_name);
3578 }
3579 keg = slab->us_keg;
3580 freei = ((uintptr_t)item - (uintptr_t)slab->us_data) / keg->uk_rsize;
3581
3582 if (BIT_ISSET(SLAB_SETSIZE, freei, &slab->us_debugfree))
3583 panic("Duplicate alloc of %p from zone %p(%s) slab %p(%d)\n",
3584 item, zone, zone->uz_name, slab, freei);
3585 BIT_SET_ATOMIC(SLAB_SETSIZE, freei, &slab->us_debugfree);
3586
3587 return;
3588}
3589
3590/*
3591 * Verifies freed addresses. Checks for alignment, valid slab membership
3592 * and duplicate frees.
3593 *
3594 */
3595static void
3596uma_dbg_free(uma_zone_t zone, uma_slab_t slab, void *item)
3597{
3598 uma_keg_t keg;
3599 int freei;
3600
3601 if (zone_first_keg(zone) == NULL)
3602 return;
3603 if (slab == NULL) {
3604 slab = uma_dbg_getslab(zone, item);
3605 if (slab == NULL)
3606 panic("uma: Freed item %p did not belong to zone %s\n",
3607 item, zone->uz_name);
3608 }
3609 keg = slab->us_keg;
3610 freei = ((uintptr_t)item - (uintptr_t)slab->us_data) / keg->uk_rsize;
3611
3612 if (freei >= keg->uk_ipers)
3613 panic("Invalid free of %p from zone %p(%s) slab %p(%d)\n",
3614 item, zone, zone->uz_name, slab, freei);
3615
3616 if (((freei * keg->uk_rsize) + slab->us_data) != item)
3617 panic("Unaligned free of %p from zone %p(%s) slab %p(%d)\n",
3618 item, zone, zone->uz_name, slab, freei);
3619
3620 if (!BIT_ISSET(SLAB_SETSIZE, freei, &slab->us_debugfree))
3621 panic("Duplicate free of %p from zone %p(%s) slab %p(%d)\n",
3622 item, zone, zone->uz_name, slab, freei);
3623
3624 BIT_CLR_ATOMIC(SLAB_SETSIZE, freei, &slab->us_debugfree);
3625}
3626#endif /* INVARIANTS */
3627
3628#ifdef DDB
3629DB_SHOW_COMMAND(uma, db_show_uma)
3630{
3631 uint64_t allocs, frees, sleeps;
3632 uma_bucket_t bucket;
3633 uma_keg_t kz;
3634 uma_zone_t z;
3635 int cachefree;
3636
3637 db_printf("%18s %8s %8s %8s %12s %8s %8s\n", "Zone", "Size", "Used",
3638 "Free", "Requests", "Sleeps", "Bucket");
3639 LIST_FOREACH(kz, &uma_kegs, uk_link) {
3640 LIST_FOREACH(z, &kz->uk_zones, uz_link) {
3641 if (kz->uk_flags & UMA_ZFLAG_INTERNAL) {
3642 allocs = z->uz_allocs;
3643 frees = z->uz_frees;
3644 sleeps = z->uz_sleeps;
3645 cachefree = 0;
3646 } else
3647 uma_zone_sumstat(z, &cachefree, &allocs,
3648 &frees, &sleeps);
3649 if (!((z->uz_flags & UMA_ZONE_SECONDARY) &&
3650 (LIST_FIRST(&kz->uk_zones) != z)))
3651 cachefree += kz->uk_free;
3652 LIST_FOREACH(bucket, &z->uz_buckets, ub_link)
3653 cachefree += bucket->ub_cnt;
3654 db_printf("%18s %8ju %8jd %8d %12ju %8ju %8u\n",
3655 z->uz_name, (uintmax_t)kz->uk_size,
3656 (intmax_t)(allocs - frees), cachefree,
3657 (uintmax_t)allocs, sleeps, z->uz_count);
3658 if (db_pager_quit)
3659 return;
3660 }
3661 }
3662}
3663
3664DB_SHOW_COMMAND(umacache, db_show_umacache)
3665{
3666 uint64_t allocs, frees;
3667 uma_bucket_t bucket;
3668 uma_zone_t z;
3669 int cachefree;
3670
3671 db_printf("%18s %8s %8s %8s %12s %8s\n", "Zone", "Size", "Used", "Free",
3672 "Requests", "Bucket");
3673 LIST_FOREACH(z, &uma_cachezones, uz_link) {
3674 uma_zone_sumstat(z, &cachefree, &allocs, &frees, NULL);
3675 LIST_FOREACH(bucket, &z->uz_buckets, ub_link)
3676 cachefree += bucket->ub_cnt;
3677 db_printf("%18s %8ju %8jd %8d %12ju %8u\n",
3678 z->uz_name, (uintmax_t)z->uz_size,
3679 (intmax_t)(allocs - frees), cachefree,
3680 (uintmax_t)allocs, z->uz_count);
3681 if (db_pager_quit)
3682 return;
3683 }
3684}
3685#endif /* DDB */
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
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice unmodified, this list of conditions, and the following
12 * disclaimer.
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.
16 *
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.
27 */
28
29/*
30 * uma_core.c Implementation of the Universal Memory allocator
31 *
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 * efficient. 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.
38 *
39 * The basic ideas stem from similar slab/zone based allocators whose algorithms
40 * are well known.
41 *
42 */
43
44/*
45 * TODO:
46 * - Improve memory usage for large allocations
47 * - Investigate cache size adjustments
48 */
49
50#include <sys/cdefs.h>
51__FBSDID("$FreeBSD: head/sys/vm/uma_core.c 302372 2016-07-06 14:09:49Z nwhitehorn $");
52
53/* I should really use ktr.. */
54/*
55#define UMA_DEBUG 1
56#define UMA_DEBUG_ALLOC 1
57#define UMA_DEBUG_ALLOC_1 1
58*/
59
60#include "opt_ddb.h"
61#include "opt_param.h"
62#include "opt_vm.h"
63
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>
71#include <sys/ktr.h>
72#include <sys/lock.h>
73#include <sys/sysctl.h>
74#include <sys/mutex.h>
75#include <sys/proc.h>
76#include <sys/random.h>
77#include <sys/rwlock.h>
78#include <sys/sbuf.h>
79#include <sys/sched.h>
80#include <sys/smp.h>
81#include <sys/taskqueue.h>
82#include <sys/vmmeter.h>
83
84#include <vm/vm.h>
85#include <vm/vm_object.h>
86#include <vm/vm_page.h>
87#include <vm/vm_pageout.h>
88#include <vm/vm_param.h>
89#include <vm/vm_map.h>
90#include <vm/vm_kern.h>
91#include <vm/vm_extern.h>
92#include <vm/uma.h>
93#include <vm/uma_int.h>
94#include <vm/uma_dbg.h>
95
96#include <ddb/ddb.h>
97
98#ifdef DEBUG_MEMGUARD
99#include <vm/memguard.h>
100#endif
101
102/*
103 * This is the zone and keg from which all zones are spawned. The idea is that
104 * even the zone & keg heads are allocated from the allocator, so we use the
105 * bss section to bootstrap us.
106 */
107static struct uma_keg masterkeg;
108static struct uma_zone masterzone_k;
109static struct uma_zone masterzone_z;
110static uma_zone_t kegs = &masterzone_k;
111static uma_zone_t zones = &masterzone_z;
112
113/* This is the zone from which all of uma_slab_t's are allocated. */
114static uma_zone_t slabzone;
115
116/*
117 * The initial hash tables come out of this zone so they can be allocated
118 * prior to malloc coming up.
119 */
120static uma_zone_t hashzone;
121
122/* The boot-time adjusted value for cache line alignment. */
123int uma_align_cache = 64 - 1;
124
125static MALLOC_DEFINE(M_UMAHASH, "UMAHash", "UMA Hash Buckets");
126
127/*
128 * Are we allowed to allocate buckets?
129 */
130static int bucketdisable = 1;
131
132/* Linked list of all kegs in the system */
133static LIST_HEAD(,uma_keg) uma_kegs = LIST_HEAD_INITIALIZER(uma_kegs);
134
135/* Linked list of all cache-only zones in the system */
136static LIST_HEAD(,uma_zone) uma_cachezones =
137 LIST_HEAD_INITIALIZER(uma_cachezones);
138
139/* This RW lock protects the keg list */
140static struct rwlock_padalign uma_rwlock;
141
142/* Linked list of boot time pages */
143static LIST_HEAD(,uma_slab) uma_boot_pages =
144 LIST_HEAD_INITIALIZER(uma_boot_pages);
145
146/* This mutex protects the boot time pages list */
147static struct mtx_padalign uma_boot_pages_mtx;
148
149static struct sx uma_drain_lock;
150
151/* Is the VM done starting up? */
152static int booted = 0;
153#define UMA_STARTUP 1
154#define UMA_STARTUP2 2
155
156/*
157 * This is the handle used to schedule events that need to happen
158 * outside of the allocation fast path.
159 */
160static struct callout uma_callout;
161#define UMA_TIMEOUT 20 /* Seconds for callout interval. */
162
163/*
164 * This structure is passed as the zone ctor arg so that I don't have to create
165 * a special allocation function just for zones.
166 */
167struct uma_zctor_args {
168 const char *name;
169 size_t size;
170 uma_ctor ctor;
171 uma_dtor dtor;
172 uma_init uminit;
173 uma_fini fini;
174 uma_import import;
175 uma_release release;
176 void *arg;
177 uma_keg_t keg;
178 int align;
179 uint32_t flags;
180};
181
182struct uma_kctor_args {
183 uma_zone_t zone;
184 size_t size;
185 uma_init uminit;
186 uma_fini fini;
187 int align;
188 uint32_t flags;
189};
190
191struct uma_bucket_zone {
192 uma_zone_t ubz_zone;
193 char *ubz_name;
194 int ubz_entries; /* Number of items it can hold. */
195 int ubz_maxsize; /* Maximum allocation size per-item. */
196};
197
198/*
199 * Compute the actual number of bucket entries to pack them in power
200 * of two sizes for more efficient space utilization.
201 */
202#define BUCKET_SIZE(n) \
203 (((sizeof(void *) * (n)) - sizeof(struct uma_bucket)) / sizeof(void *))
204
205#define BUCKET_MAX BUCKET_SIZE(256)
206
207struct uma_bucket_zone bucket_zones[] = {
208 { NULL, "4 Bucket", BUCKET_SIZE(4), 4096 },
209 { NULL, "6 Bucket", BUCKET_SIZE(6), 3072 },
210 { NULL, "8 Bucket", BUCKET_SIZE(8), 2048 },
211 { NULL, "12 Bucket", BUCKET_SIZE(12), 1536 },
212 { NULL, "16 Bucket", BUCKET_SIZE(16), 1024 },
213 { NULL, "32 Bucket", BUCKET_SIZE(32), 512 },
214 { NULL, "64 Bucket", BUCKET_SIZE(64), 256 },
215 { NULL, "128 Bucket", BUCKET_SIZE(128), 128 },
216 { NULL, "256 Bucket", BUCKET_SIZE(256), 64 },
217 { NULL, NULL, 0}
218};
219
220/*
221 * Flags and enumerations to be passed to internal functions.
222 */
223enum zfreeskip { SKIP_NONE = 0, SKIP_DTOR, SKIP_FINI };
224
225/* Prototypes.. */
226
227static void *noobj_alloc(uma_zone_t, vm_size_t, uint8_t *, int);
228static void *page_alloc(uma_zone_t, vm_size_t, uint8_t *, int);
229static void *startup_alloc(uma_zone_t, vm_size_t, uint8_t *, int);
230static void page_free(void *, vm_size_t, uint8_t);
231static uma_slab_t keg_alloc_slab(uma_keg_t, uma_zone_t, int);
232static void cache_drain(uma_zone_t);
233static void bucket_drain(uma_zone_t, uma_bucket_t);
234static void bucket_cache_drain(uma_zone_t zone);
235static int keg_ctor(void *, int, void *, int);
236static void keg_dtor(void *, int, void *);
237static int zone_ctor(void *, int, void *, int);
238static void zone_dtor(void *, int, void *);
239static int zero_init(void *, int, int);
240static void keg_small_init(uma_keg_t keg);
241static void keg_large_init(uma_keg_t keg);
242static void zone_foreach(void (*zfunc)(uma_zone_t));
243static void zone_timeout(uma_zone_t zone);
244static int hash_alloc(struct uma_hash *);
245static int hash_expand(struct uma_hash *, struct uma_hash *);
246static void hash_free(struct uma_hash *hash);
247static void uma_timeout(void *);
248static void uma_startup3(void);
249static void *zone_alloc_item(uma_zone_t, void *, int);
250static void zone_free_item(uma_zone_t, void *, void *, enum zfreeskip);
251static void bucket_enable(void);
252static void bucket_init(void);
253static uma_bucket_t bucket_alloc(uma_zone_t zone, void *, int);
254static void bucket_free(uma_zone_t zone, uma_bucket_t, void *);
255static void bucket_zone_drain(void);
256static uma_bucket_t zone_alloc_bucket(uma_zone_t zone, void *, int flags);
257static uma_slab_t zone_fetch_slab(uma_zone_t zone, uma_keg_t last, int flags);
258static uma_slab_t zone_fetch_slab_multi(uma_zone_t zone, uma_keg_t last, int flags);
259static void *slab_alloc_item(uma_keg_t keg, uma_slab_t slab);
260static void slab_free_item(uma_keg_t keg, uma_slab_t slab, void *item);
261static uma_keg_t uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit,
262 uma_fini fini, int align, uint32_t flags);
263static int zone_import(uma_zone_t zone, void **bucket, int max, int flags);
264static void zone_release(uma_zone_t zone, void **bucket, int cnt);
265static void uma_zero_item(void *item, uma_zone_t zone);
266
267void uma_print_zone(uma_zone_t);
268void uma_print_stats(void);
269static int sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS);
270static int sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS);
271
272#ifdef INVARIANTS
273static void uma_dbg_free(uma_zone_t zone, uma_slab_t slab, void *item);
274static void uma_dbg_alloc(uma_zone_t zone, uma_slab_t slab, void *item);
275#endif
276
277SYSINIT(uma_startup3, SI_SUB_VM_CONF, SI_ORDER_SECOND, uma_startup3, NULL);
278
279SYSCTL_PROC(_vm, OID_AUTO, zone_count, CTLFLAG_RD|CTLTYPE_INT,
280 0, 0, sysctl_vm_zone_count, "I", "Number of UMA zones");
281
282SYSCTL_PROC(_vm, OID_AUTO, zone_stats, CTLFLAG_RD|CTLTYPE_STRUCT,
283 0, 0, sysctl_vm_zone_stats, "s,struct uma_type_header", "Zone Stats");
284
285static int zone_warnings = 1;
286SYSCTL_INT(_vm, OID_AUTO, zone_warnings, CTLFLAG_RWTUN, &zone_warnings, 0,
287 "Warn when UMA zones becomes full");
288
289/*
290 * This routine checks to see whether or not it's safe to enable buckets.
291 */
292static void
293bucket_enable(void)
294{
295 bucketdisable = vm_page_count_min();
296}
297
298/*
299 * Initialize bucket_zones, the array of zones of buckets of various sizes.
300 *
301 * For each zone, calculate the memory required for each bucket, consisting
302 * of the header and an array of pointers.
303 */
304static void
305bucket_init(void)
306{
307 struct uma_bucket_zone *ubz;
308 int size;
309
310 for (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);
316 }
317}
318
319/*
320 * Given a desired number of entries for a bucket, return the zone from which
321 * to allocate the bucket.
322 */
323static struct uma_bucket_zone *
324bucket_zone_lookup(int entries)
325{
326 struct uma_bucket_zone *ubz;
327
328 for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++)
329 if (ubz->ubz_entries >= entries)
330 return (ubz);
331 ubz--;
332 return (ubz);
333}
334
335static int
336bucket_select(int size)
337{
338 struct uma_bucket_zone *ubz;
339
340 ubz = &bucket_zones[0];
341 if (size > ubz->ubz_maxsize)
342 return MAX((ubz->ubz_maxsize * ubz->ubz_entries) / size, 1);
343
344 for (; ubz->ubz_entries != 0; ubz++)
345 if (ubz->ubz_maxsize < size)
346 break;
347 ubz--;
348 return (ubz->ubz_entries);
349}
350
351static uma_bucket_t
352bucket_alloc(uma_zone_t zone, void *udata, int flags)
353{
354 struct uma_bucket_zone *ubz;
355 uma_bucket_t bucket;
356
357 /*
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.
362 */
363 if (bucketdisable)
364 return (NULL);
365 /*
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
373 * free path.
374 */
375 if ((zone->uz_flags & UMA_ZFLAG_BUCKET) == 0)
376 udata = (void *)(uintptr_t)zone->uz_flags;
377 else {
378 if ((uintptr_t)udata & UMA_ZFLAG_BUCKET)
379 return (NULL);
380 udata = (void *)((uintptr_t)udata | UMA_ZFLAG_BUCKET);
381 }
382 if ((uintptr_t)udata & UMA_ZFLAG_CACHEONLY)
383 flags |= M_NOVM;
384 ubz = bucket_zone_lookup(zone->uz_count);
385 if (ubz->ubz_zone == zone && (ubz + 1)->ubz_entries != 0)
386 ubz++;
387 bucket = uma_zalloc_arg(ubz->ubz_zone, udata, flags);
388 if (bucket) {
389#ifdef INVARIANTS
390 bzero(bucket->ub_bucket, sizeof(void *) * ubz->ubz_entries);
391#endif
392 bucket->ub_cnt = 0;
393 bucket->ub_entries = ubz->ubz_entries;
394 }
395
396 return (bucket);
397}
398
399static void
400bucket_free(uma_zone_t zone, uma_bucket_t bucket, void *udata)
401{
402 struct uma_bucket_zone *ubz;
403
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);
410}
411
412static void
413bucket_zone_drain(void)
414{
415 struct uma_bucket_zone *ubz;
416
417 for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++)
418 zone_drain(ubz->ubz_zone);
419}
420
421static void
422zone_log_warning(uma_zone_t zone)
423{
424 static const struct timeval warninterval = { 300, 0 };
425
426 if (!zone_warnings || zone->uz_warning == NULL)
427 return;
428
429 if (ratecheck(&zone->uz_ratecheck, &warninterval))
430 printf("[zone: %s] %s\n", zone->uz_name, zone->uz_warning);
431}
432
433static inline void
434zone_maxaction(uma_zone_t zone)
435{
436
437 if (zone->uz_maxaction.ta_func != NULL)
438 taskqueue_enqueue(taskqueue_thread, &zone->uz_maxaction);
439}
440
441static void
442zone_foreach_keg(uma_zone_t zone, void (*kegfn)(uma_keg_t))
443{
444 uma_klink_t klink;
445
446 LIST_FOREACH(klink, &zone->uz_kegs, kl_link)
447 kegfn(klink->kl_keg);
448}
449
450/*
451 * Routine called by timeout which is used to fire off some time interval
452 * based calculations. (stats, hash size, etc.)
453 *
454 * Arguments:
455 * arg Unused
456 *
457 * Returns:
458 * Nothing
459 */
460static void
461uma_timeout(void *unused)
462{
463 bucket_enable();
464 zone_foreach(zone_timeout);
465
466 /* Reschedule this event */
467 callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL);
468}
469
470/*
471 * Routine to perform timeout driven calculations. This expands the
472 * hashes and does per cpu statistics aggregation.
473 *
474 * Returns nothing.
475 */
476static void
477keg_timeout(uma_keg_t keg)
478{
479
480 KEG_LOCK(keg);
481 /*
482 * Expand the keg hash table.
483 *
484 * This is done if the number of slabs is larger than the hash size.
485 * What I'm trying to do here is completely reduce collisions. This
486 * may be a little aggressive. Should I allow for two collisions max?
487 */
488 if (keg->uk_flags & UMA_ZONE_HASH &&
489 keg->uk_pages / keg->uk_ppera >= keg->uk_hash.uh_hashsize) {
490 struct uma_hash newhash;
491 struct uma_hash oldhash;
492 int ret;
493
494 /*
495 * This is so involved because allocating and freeing
496 * while the keg lock is held will lead to deadlock.
497 * I have to do everything in stages and check for
498 * races.
499 */
500 newhash = keg->uk_hash;
501 KEG_UNLOCK(keg);
502 ret = hash_alloc(&newhash);
503 KEG_LOCK(keg);
504 if (ret) {
505 if (hash_expand(&keg->uk_hash, &newhash)) {
506 oldhash = keg->uk_hash;
507 keg->uk_hash = newhash;
508 } else
509 oldhash = newhash;
510
511 KEG_UNLOCK(keg);
512 hash_free(&oldhash);
513 return;
514 }
515 }
516 KEG_UNLOCK(keg);
517}
518
519static void
520zone_timeout(uma_zone_t zone)
521{
522
523 zone_foreach_keg(zone, &keg_timeout);
524}
525
526/*
527 * Allocate and zero fill the next sized hash table from the appropriate
528 * backing store.
529 *
530 * Arguments:
531 * hash A new hash structure with the old hash size in uh_hashsize
532 *
533 * Returns:
534 * 1 on success and 0 on failure.
535 */
536static int
537hash_alloc(struct uma_hash *hash)
538{
539 int oldsize;
540 int alloc;
541
542 oldsize = hash->uh_hashsize;
543
544 /* We're just going to go to a power of two greater */
545 if (oldsize) {
546 hash->uh_hashsize = oldsize * 2;
547 alloc = sizeof(hash->uh_slab_hash[0]) * hash->uh_hashsize;
548 hash->uh_slab_hash = (struct slabhead *)malloc(alloc,
549 M_UMAHASH, M_NOWAIT);
550 } else {
551 alloc = sizeof(hash->uh_slab_hash[0]) * UMA_HASH_SIZE_INIT;
552 hash->uh_slab_hash = zone_alloc_item(hashzone, NULL,
553 M_WAITOK);
554 hash->uh_hashsize = UMA_HASH_SIZE_INIT;
555 }
556 if (hash->uh_slab_hash) {
557 bzero(hash->uh_slab_hash, alloc);
558 hash->uh_hashmask = hash->uh_hashsize - 1;
559 return (1);
560 }
561
562 return (0);
563}
564
565/*
566 * Expands the hash table for HASH zones. This is done from zone_timeout
567 * to reduce collisions. This must not be done in the regular allocation
568 * path, otherwise, we can recurse on the vm while allocating pages.
569 *
570 * Arguments:
571 * oldhash The hash you want to expand
572 * newhash The hash structure for the new table
573 *
574 * Returns:
575 * Nothing
576 *
577 * Discussion:
578 */
579static int
580hash_expand(struct uma_hash *oldhash, struct uma_hash *newhash)
581{
582 uma_slab_t slab;
583 int hval;
584 int i;
585
586 if (!newhash->uh_slab_hash)
587 return (0);
588
589 if (oldhash->uh_hashsize >= newhash->uh_hashsize)
590 return (0);
591
592 /*
593 * I need to investigate hash algorithms for resizing without a
594 * full rehash.
595 */
596
597 for (i = 0; i < oldhash->uh_hashsize; i++)
598 while (!SLIST_EMPTY(&oldhash->uh_slab_hash[i])) {
599 slab = SLIST_FIRST(&oldhash->uh_slab_hash[i]);
600 SLIST_REMOVE_HEAD(&oldhash->uh_slab_hash[i], us_hlink);
601 hval = UMA_HASH(newhash, slab->us_data);
602 SLIST_INSERT_HEAD(&newhash->uh_slab_hash[hval],
603 slab, us_hlink);
604 }
605
606 return (1);
607}
608
609/*
610 * Free the hash bucket to the appropriate backing store.
611 *
612 * Arguments:
613 * slab_hash The hash bucket we're freeing
614 * hashsize The number of entries in that hash bucket
615 *
616 * Returns:
617 * Nothing
618 */
619static void
620hash_free(struct uma_hash *hash)
621{
622 if (hash->uh_slab_hash == NULL)
623 return;
624 if (hash->uh_hashsize == UMA_HASH_SIZE_INIT)
625 zone_free_item(hashzone, hash->uh_slab_hash, NULL, SKIP_NONE);
626 else
627 free(hash->uh_slab_hash, M_UMAHASH);
628}
629
630/*
631 * Frees all outstanding items in a bucket
632 *
633 * Arguments:
634 * zone The zone to free to, must be unlocked.
635 * bucket The free/alloc bucket with items, cpu queue must be locked.
636 *
637 * Returns:
638 * Nothing
639 */
640
641static void
642bucket_drain(uma_zone_t zone, uma_bucket_t bucket)
643{
644 int i;
645
646 if (bucket == NULL)
647 return;
648
649 if (zone->uz_fini)
650 for (i = 0; i < bucket->ub_cnt; i++)
651 zone->uz_fini(bucket->ub_bucket[i], zone->uz_size);
652 zone->uz_release(zone->uz_arg, bucket->ub_bucket, bucket->ub_cnt);
653 bucket->ub_cnt = 0;
654}
655
656/*
657 * Drains the per cpu caches for a zone.
658 *
659 * NOTE: This may only be called while the zone is being turn down, and not
660 * during normal operation. This is necessary in order that we do not have
661 * to migrate CPUs to drain the per-CPU caches.
662 *
663 * Arguments:
664 * zone The zone to drain, must be unlocked.
665 *
666 * Returns:
667 * Nothing
668 */
669static void
670cache_drain(uma_zone_t zone)
671{
672 uma_cache_t cache;
673 int cpu;
674
675 /*
676 * XXX: It is safe to not lock the per-CPU caches, because we're
677 * tearing down the zone anyway. I.e., there will be no further use
678 * of the caches at this point.
679 *
680 * XXX: It would good to be able to assert that the zone is being
681 * torn down to prevent improper use of cache_drain().
682 *
683 * XXX: We lock the zone before passing into bucket_cache_drain() as
684 * it is used elsewhere. Should the tear-down path be made special
685 * there in some form?
686 */
687 CPU_FOREACH(cpu) {
688 cache = &zone->uz_cpu[cpu];
689 bucket_drain(zone, cache->uc_allocbucket);
690 bucket_drain(zone, cache->uc_freebucket);
691 if (cache->uc_allocbucket != NULL)
692 bucket_free(zone, cache->uc_allocbucket, NULL);
693 if (cache->uc_freebucket != NULL)
694 bucket_free(zone, cache->uc_freebucket, NULL);
695 cache->uc_allocbucket = cache->uc_freebucket = NULL;
696 }
697 ZONE_LOCK(zone);
698 bucket_cache_drain(zone);
699 ZONE_UNLOCK(zone);
700}
701
702static void
703cache_shrink(uma_zone_t zone)
704{
705
706 if (zone->uz_flags & UMA_ZFLAG_INTERNAL)
707 return;
708
709 ZONE_LOCK(zone);
710 zone->uz_count = (zone->uz_count_min + zone->uz_count) / 2;
711 ZONE_UNLOCK(zone);
712}
713
714static void
715cache_drain_safe_cpu(uma_zone_t zone)
716{
717 uma_cache_t cache;
718 uma_bucket_t b1, b2;
719
720 if (zone->uz_flags & UMA_ZFLAG_INTERNAL)
721 return;
722
723 b1 = b2 = NULL;
724 ZONE_LOCK(zone);
725 critical_enter();
726 cache = &zone->uz_cpu[curcpu];
727 if (cache->uc_allocbucket) {
728 if (cache->uc_allocbucket->ub_cnt != 0)
729 LIST_INSERT_HEAD(&zone->uz_buckets,
730 cache->uc_allocbucket, ub_link);
731 else
732 b1 = cache->uc_allocbucket;
733 cache->uc_allocbucket = NULL;
734 }
735 if (cache->uc_freebucket) {
736 if (cache->uc_freebucket->ub_cnt != 0)
737 LIST_INSERT_HEAD(&zone->uz_buckets,
738 cache->uc_freebucket, ub_link);
739 else
740 b2 = cache->uc_freebucket;
741 cache->uc_freebucket = NULL;
742 }
743 critical_exit();
744 ZONE_UNLOCK(zone);
745 if (b1)
746 bucket_free(zone, b1, NULL);
747 if (b2)
748 bucket_free(zone, b2, NULL);
749}
750
751/*
752 * Safely drain per-CPU caches of a zone(s) to alloc bucket.
753 * This is an expensive call because it needs to bind to all CPUs
754 * one by one and enter a critical section on each of them in order
755 * to safely access their cache buckets.
756 * Zone lock must not be held on call this function.
757 */
758static void
759cache_drain_safe(uma_zone_t zone)
760{
761 int cpu;
762
763 /*
764 * Polite bucket sizes shrinking was not enouth, shrink aggressively.
765 */
766 if (zone)
767 cache_shrink(zone);
768 else
769 zone_foreach(cache_shrink);
770
771 CPU_FOREACH(cpu) {
772 thread_lock(curthread);
773 sched_bind(curthread, cpu);
774 thread_unlock(curthread);
775
776 if (zone)
777 cache_drain_safe_cpu(zone);
778 else
779 zone_foreach(cache_drain_safe_cpu);
780 }
781 thread_lock(curthread);
782 sched_unbind(curthread);
783 thread_unlock(curthread);
784}
785
786/*
787 * Drain the cached buckets from a zone. Expects a locked zone on entry.
788 */
789static void
790bucket_cache_drain(uma_zone_t zone)
791{
792 uma_bucket_t bucket;
793
794 /*
795 * Drain the bucket queues and free the buckets, we just keep two per
796 * cpu (alloc/free).
797 */
798 while ((bucket = LIST_FIRST(&zone->uz_buckets)) != NULL) {
799 LIST_REMOVE(bucket, ub_link);
800 ZONE_UNLOCK(zone);
801 bucket_drain(zone, bucket);
802 bucket_free(zone, bucket, NULL);
803 ZONE_LOCK(zone);
804 }
805
806 /*
807 * Shrink further bucket sizes. Price of single zone lock collision
808 * is probably lower then price of global cache drain.
809 */
810 if (zone->uz_count > zone->uz_count_min)
811 zone->uz_count--;
812}
813
814static void
815keg_free_slab(uma_keg_t keg, uma_slab_t slab, int start)
816{
817 uint8_t *mem;
818 int i;
819 uint8_t flags;
820
821 mem = slab->us_data;
822 flags = slab->us_flags;
823 i = start;
824 if (keg->uk_fini != NULL) {
825 for (i--; i > -1; i--)
826 keg->uk_fini(slab->us_data + (keg->uk_rsize * i),
827 keg->uk_size);
828 }
829 if (keg->uk_flags & UMA_ZONE_OFFPAGE)
830 zone_free_item(keg->uk_slabzone, slab, NULL, SKIP_NONE);
831#ifdef UMA_DEBUG
832 printf("%s: Returning %d bytes.\n", keg->uk_name,
833 PAGE_SIZE * keg->uk_ppera);
834#endif
835 keg->uk_freef(mem, PAGE_SIZE * keg->uk_ppera, flags);
836}
837
838/*
839 * Frees pages from a keg back to the system. This is done on demand from
840 * the pageout daemon.
841 *
842 * Returns nothing.
843 */
844static void
845keg_drain(uma_keg_t keg)
846{
847 struct slabhead freeslabs = { 0 };
848 uma_slab_t slab;
849 uma_slab_t n;
850
851 /*
852 * We don't want to take pages from statically allocated kegs at this
853 * time
854 */
855 if (keg->uk_flags & UMA_ZONE_NOFREE || keg->uk_freef == NULL)
856 return;
857
858#ifdef UMA_DEBUG
859 printf("%s free items: %u\n", keg->uk_name, keg->uk_free);
860#endif
861 KEG_LOCK(keg);
862 if (keg->uk_free == 0)
863 goto finished;
864
865 slab = LIST_FIRST(&keg->uk_free_slab);
866 while (slab) {
867 n = LIST_NEXT(slab, us_link);
868
869 /* We have no where to free these to */
870 if (slab->us_flags & UMA_SLAB_BOOT) {
871 slab = n;
872 continue;
873 }
874
875 LIST_REMOVE(slab, us_link);
876 keg->uk_pages -= keg->uk_ppera;
877 keg->uk_free -= keg->uk_ipers;
878
879 if (keg->uk_flags & UMA_ZONE_HASH)
880 UMA_HASH_REMOVE(&keg->uk_hash, slab, slab->us_data);
881
882 SLIST_INSERT_HEAD(&freeslabs, slab, us_hlink);
883
884 slab = n;
885 }
886finished:
887 KEG_UNLOCK(keg);
888
889 while ((slab = SLIST_FIRST(&freeslabs)) != NULL) {
890 SLIST_REMOVE(&freeslabs, slab, uma_slab, us_hlink);
891 keg_free_slab(keg, slab, keg->uk_ipers);
892 }
893}
894
895static void
896zone_drain_wait(uma_zone_t zone, int waitok)
897{
898
899 /*
900 * Set draining to interlock with zone_dtor() so we can release our
901 * locks as we go. Only dtor() should do a WAITOK call since it
902 * is the only call that knows the structure will still be available
903 * when it wakes up.
904 */
905 ZONE_LOCK(zone);
906 while (zone->uz_flags & UMA_ZFLAG_DRAINING) {
907 if (waitok == M_NOWAIT)
908 goto out;
909 msleep(zone, zone->uz_lockptr, PVM, "zonedrain", 1);
910 }
911 zone->uz_flags |= UMA_ZFLAG_DRAINING;
912 bucket_cache_drain(zone);
913 ZONE_UNLOCK(zone);
914 /*
915 * The DRAINING flag protects us from being freed while
916 * we're running. Normally the uma_rwlock would protect us but we
917 * must be able to release and acquire the right lock for each keg.
918 */
919 zone_foreach_keg(zone, &keg_drain);
920 ZONE_LOCK(zone);
921 zone->uz_flags &= ~UMA_ZFLAG_DRAINING;
922 wakeup(zone);
923out:
924 ZONE_UNLOCK(zone);
925}
926
927void
928zone_drain(uma_zone_t zone)
929{
930
931 zone_drain_wait(zone, M_NOWAIT);
932}
933
934/*
935 * Allocate a new slab for a keg. This does not insert the slab onto a list.
936 *
937 * Arguments:
938 * wait Shall we wait?
939 *
940 * Returns:
941 * The slab that was allocated or NULL if there is no memory and the
942 * caller specified M_NOWAIT.
943 */
944static uma_slab_t
945keg_alloc_slab(uma_keg_t keg, uma_zone_t zone, int wait)
946{
947 uma_alloc allocf;
948 uma_slab_t slab;
949 uint8_t *mem;
950 uint8_t flags;
951 int i;
952
953 mtx_assert(&keg->uk_lock, MA_OWNED);
954 slab = NULL;
955 mem = NULL;
956
957#ifdef UMA_DEBUG
958 printf("alloc_slab: Allocating a new slab for %s\n", keg->uk_name);
959#endif
960 allocf = keg->uk_allocf;
961 KEG_UNLOCK(keg);
962
963 if (keg->uk_flags & UMA_ZONE_OFFPAGE) {
964 slab = zone_alloc_item(keg->uk_slabzone, NULL, wait);
965 if (slab == NULL)
966 goto out;
967 }
968
969 /*
970 * This reproduces the old vm_zone behavior of zero filling pages the
971 * first time they are added to a zone.
972 *
973 * Malloced items are zeroed in uma_zalloc.
974 */
975
976 if ((keg->uk_flags & UMA_ZONE_MALLOC) == 0)
977 wait |= M_ZERO;
978 else
979 wait &= ~M_ZERO;
980
981 if (keg->uk_flags & UMA_ZONE_NODUMP)
982 wait |= M_NODUMP;
983
984 /* zone is passed for legacy reasons. */
985 mem = allocf(zone, keg->uk_ppera * PAGE_SIZE, &flags, wait);
986 if (mem == NULL) {
987 if (keg->uk_flags & UMA_ZONE_OFFPAGE)
988 zone_free_item(keg->uk_slabzone, slab, NULL, SKIP_NONE);
989 slab = NULL;
990 goto out;
991 }
992
993 /* Point the slab into the allocated memory */
994 if (!(keg->uk_flags & UMA_ZONE_OFFPAGE))
995 slab = (uma_slab_t )(mem + keg->uk_pgoff);
996
997 if (keg->uk_flags & UMA_ZONE_VTOSLAB)
998 for (i = 0; i < keg->uk_ppera; i++)
999 vsetslab((vm_offset_t)mem + (i * PAGE_SIZE), slab);
1000
1001 slab->us_keg = keg;
1002 slab->us_data = mem;
1003 slab->us_freecount = keg->uk_ipers;
1004 slab->us_flags = flags;
1005 BIT_FILL(SLAB_SETSIZE, &slab->us_free);
1006#ifdef INVARIANTS
1007 BIT_ZERO(SLAB_SETSIZE, &slab->us_debugfree);
1008#endif
1009
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)
1014 break;
1015 if (i != keg->uk_ipers) {
1016 keg_free_slab(keg, slab, i);
1017 slab = NULL;
1018 goto out;
1019 }
1020 }
1021out:
1022 KEG_LOCK(keg);
1023
1024 if (slab != NULL) {
1025 if (keg->uk_flags & UMA_ZONE_HASH)
1026 UMA_HASH_INSERT(&keg->uk_hash, slab, mem);
1027
1028 keg->uk_pages += keg->uk_ppera;
1029 keg->uk_free += keg->uk_ipers;
1030 }
1031
1032 return (slab);
1033}
1034
1035/*
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
1038 * the VM is ready.
1039 */
1040static void *
1041startup_alloc(uma_zone_t zone, vm_size_t bytes, uint8_t *pflag, int wait)
1042{
1043 uma_keg_t keg;
1044 uma_slab_t tmps;
1045 int pages, check_pages;
1046
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"));
1051
1052 /*
1053 * Check our small startup cache to see if it has pages remaining.
1054 */
1055 mtx_lock(&uma_boot_pages_mtx);
1056
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);
1061 if (tmps != NULL) {
1062 /*
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.
1066 */
1067 while (pages-- > 0) {
1068 tmps = LIST_FIRST(&uma_boot_pages);
1069 LIST_REMOVE(tmps, us_link);
1070 }
1071 mtx_unlock(&uma_boot_pages_mtx);
1072 *pflag = tmps->us_flags;
1073 return (tmps->us_data);
1074 }
1075 mtx_unlock(&uma_boot_pages_mtx);
1076 if (booted < UMA_STARTUP2)
1077 panic("UMA: Increase vm.boot_pages");
1078 /*
1079 * Now that we've booted reset these users to their real allocator.
1080 */
1081#ifdef UMA_MD_SMALL_ALLOC
1082 keg->uk_allocf = (keg->uk_ppera > 1) ? page_alloc : uma_small_alloc;
1083#else
1084 keg->uk_allocf = page_alloc;
1085#endif
1086 return keg->uk_allocf(zone, bytes, pflag, wait);
1087}
1088
1089/*
1090 * Allocates a number of pages from the system
1091 *
1092 * Arguments:
1093 * bytes The number of bytes requested
1094 * wait Shall we wait?
1095 *
1096 * Returns:
1097 * A pointer to the alloced memory or possibly
1098 * NULL if M_NOWAIT is set.
1099 */
1100static void *
1101page_alloc(uma_zone_t zone, vm_size_t bytes, uint8_t *pflag, int wait)
1102{
1103 void *p; /* Returned page */
1104
1105 *pflag = UMA_SLAB_KMEM;
1106 p = (void *) kmem_malloc(kmem_arena, bytes, wait);
1107
1108 return (p);
1109}
1110
1111/*
1112 * Allocates a number of pages from within an object
1113 *
1114 * Arguments:
1115 * bytes The number of bytes requested
1116 * wait Shall we wait?
1117 *
1118 * Returns:
1119 * A pointer to the alloced memory or possibly
1120 * NULL if M_NOWAIT is set.
1121 */
1122static void *
1123noobj_alloc(uma_zone_t zone, vm_size_t bytes, uint8_t *flags, int wait)
1124{
1125 TAILQ_HEAD(, vm_page) alloctail;
1126 u_long npages;
1127 vm_offset_t retkva, zkva;
1128 vm_page_t p, p_next;
1129 uma_keg_t keg;
1130
1131 TAILQ_INIT(&alloctail);
1132 keg = zone_first_keg(zone);
1133
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);
1138 if (p != NULL) {
1139 /*
1140 * Since the page does not belong to an object, its
1141 * listq is unused.
1142 */
1143 TAILQ_INSERT_TAIL(&alloctail, p, listq);
1144 npages--;
1145 continue;
1146 }
1147 if (wait & M_WAITOK) {
1148 VM_WAIT;
1149 continue;
1150 }
1151
1152 /*
1153 * Page allocation failed, free intermediate pages and
1154 * exit.
1155 */
1156 TAILQ_FOREACH_SAFE(p, &alloctail, listq, p_next) {
1157 vm_page_unwire(p, PQ_NONE);
1158 vm_page_free(p);
1159 }
1160 return (NULL);
1161 }
1162 *flags = UMA_SLAB_PRIV;
1163 zkva = keg->uk_kva +
1164 atomic_fetchadd_long(&keg->uk_offset, round_page(bytes));
1165 retkva = zkva;
1166 TAILQ_FOREACH(p, &alloctail, listq) {
1167 pmap_qenter(zkva, &p, 1);
1168 zkva += PAGE_SIZE;
1169 }
1170
1171 return ((void *)retkva);
1172}
1173
1174/*
1175 * Frees a number of pages to the system
1176 *
1177 * Arguments:
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
1181 *
1182 * Returns:
1183 * Nothing
1184 */
1185static void
1186page_free(void *mem, vm_size_t size, uint8_t flags)
1187{
1188 struct vmem *vmem;
1189
1190 if (flags & UMA_SLAB_KMEM)
1191 vmem = kmem_arena;
1192 else if (flags & UMA_SLAB_KERNEL)
1193 vmem = kernel_arena;
1194 else
1195 panic("UMA: page_free used with invalid flags %d", flags);
1196
1197 kmem_free(vmem, (vm_offset_t)mem, size);
1198}
1199
1200/*
1201 * Zero fill initializer
1202 *
1203 * Arguments/Returns follow uma_init specifications
1204 */
1205static int
1206zero_init(void *mem, int size, int flags)
1207{
1208 bzero(mem, size);
1209 return (0);
1210}
1211
1212/*
1213 * Finish creating a small uma keg. This calculates ipers, and the keg size.
1214 *
1215 * Arguments
1216 * keg The zone we should initialize
1217 *
1218 * Returns
1219 * Nothing
1220 */
1221static void
1222keg_small_init(uma_keg_t keg)
1223{
1224 u_int rsize;
1225 u_int memused;
1226 u_int wastedspace;
1227 u_int shsize;
1228
1229 if (keg->uk_flags & UMA_ZONE_PCPU) {
1230 u_int ncpus = (mp_maxid + 1) ? (mp_maxid + 1) : MAXCPU;
1231
1232 keg->uk_slabsize = sizeof(struct pcpu);
1233 keg->uk_ppera = howmany(ncpus * sizeof(struct pcpu),
1234 PAGE_SIZE);
1235 } else {
1236 keg->uk_slabsize = UMA_SLAB_SIZE;
1237 keg->uk_ppera = 1;
1238 }
1239
1240 /*
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.
1244 */
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;
1251
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));
1255
1256 if (keg->uk_flags & UMA_ZONE_OFFPAGE)
1257 shsize = 0;
1258 else
1259 shsize = sizeof(struct uma_slab);
1260
1261 keg->uk_ipers = (keg->uk_slabsize - shsize) / rsize;
1262 KASSERT(keg->uk_ipers > 0 && keg->uk_ipers <= SLAB_SETSIZE,
1263 ("%s: keg->uk_ipers %u", __func__, keg->uk_ipers));
1264
1265 memused = keg->uk_ipers * rsize + shsize;
1266 wastedspace = keg->uk_slabsize - memused;
1267
1268 /*
1269 * We can't do OFFPAGE if we're internal or if we've been
1270 * asked to not go to the VM for buckets. If we do this we
1271 * may end up going to the VM for slabs which we do not
1272 * want to do if we're UMA_ZFLAG_CACHEONLY as a result
1273 * of UMA_ZONE_VM, which clearly forbids it.
1274 */
1275 if ((keg->uk_flags & UMA_ZFLAG_INTERNAL) ||
1276 (keg->uk_flags & UMA_ZFLAG_CACHEONLY))
1277 return;
1278
1279 /*
1280 * See if using an OFFPAGE slab will limit our waste. Only do
1281 * this if it permits more items per-slab.
1282 *
1283 * XXX We could try growing slabsize to limit max waste as well.
1284 * Historically this was not done because the VM could not
1285 * efficiently handle contiguous allocations.
1286 */
1287 if ((wastedspace >= keg->uk_slabsize / UMA_MAX_WASTE) &&
1288 (keg->uk_ipers < (keg->uk_slabsize / keg->uk_rsize))) {
1289 keg->uk_ipers = keg->uk_slabsize / keg->uk_rsize;
1290 KASSERT(keg->uk_ipers > 0 && keg->uk_ipers <= SLAB_SETSIZE,
1291 ("%s: keg->uk_ipers %u", __func__, keg->uk_ipers));
1292#ifdef UMA_DEBUG
1293 printf("UMA decided we need offpage slab headers for "
1294 "keg: %s, calculated wastedspace = %d, "
1295 "maximum wasted space allowed = %d, "
1296 "calculated ipers = %d, "
1297 "new wasted space = %d\n", keg->uk_name, wastedspace,
1298 keg->uk_slabsize / UMA_MAX_WASTE, keg->uk_ipers,
1299 keg->uk_slabsize - keg->uk_ipers * keg->uk_rsize);
1300#endif
1301 keg->uk_flags |= UMA_ZONE_OFFPAGE;
1302 }
1303
1304 if ((keg->uk_flags & UMA_ZONE_OFFPAGE) &&
1305 (keg->uk_flags & UMA_ZONE_VTOSLAB) == 0)
1306 keg->uk_flags |= UMA_ZONE_HASH;
1307}
1308
1309/*
1310 * Finish creating a large (> UMA_SLAB_SIZE) uma kegs. Just give in and do
1311 * OFFPAGE for now. When I can allow for more dynamic slab sizes this will be
1312 * more complicated.
1313 *
1314 * Arguments
1315 * keg The keg we should initialize
1316 *
1317 * Returns
1318 * Nothing
1319 */
1320static void
1321keg_large_init(uma_keg_t keg)
1322{
1323 u_int shsize;
1324
1325 KASSERT(keg != NULL, ("Keg is null in keg_large_init"));
1326 KASSERT((keg->uk_flags & UMA_ZFLAG_CACHEONLY) == 0,
1327 ("keg_large_init: Cannot large-init a UMA_ZFLAG_CACHEONLY keg"));
1328 KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0,
1329 ("%s: Cannot large-init a UMA_ZONE_PCPU keg", __func__));
1330
1331 keg->uk_ppera = howmany(keg->uk_size, PAGE_SIZE);
1332 keg->uk_slabsize = keg->uk_ppera * PAGE_SIZE;
1333 keg->uk_ipers = 1;
1334 keg->uk_rsize = keg->uk_size;
1335
1336 /* We can't do OFFPAGE if we're internal, bail out here. */
1337 if (keg->uk_flags & UMA_ZFLAG_INTERNAL)
1338 return;
1339
1340 /* Check whether we have enough space to not do OFFPAGE. */
1341 if ((keg->uk_flags & UMA_ZONE_OFFPAGE) == 0) {
1342 shsize = sizeof(struct uma_slab);
1343 if (shsize & UMA_ALIGN_PTR)
1344 shsize = (shsize & ~UMA_ALIGN_PTR) +
1345 (UMA_ALIGN_PTR + 1);
1346
1347 if ((PAGE_SIZE * keg->uk_ppera) - keg->uk_rsize < shsize)
1348 keg->uk_flags |= UMA_ZONE_OFFPAGE;
1349 }
1350
1351 if ((keg->uk_flags & UMA_ZONE_OFFPAGE) &&
1352 (keg->uk_flags & UMA_ZONE_VTOSLAB) == 0)
1353 keg->uk_flags |= UMA_ZONE_HASH;
1354}
1355
1356static void
1357keg_cachespread_init(uma_keg_t keg)
1358{
1359 int alignsize;
1360 int trailer;
1361 int pages;
1362 int rsize;
1363
1364 KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0,
1365 ("%s: Cannot cachespread-init a UMA_ZONE_PCPU keg", __func__));
1366
1367 alignsize = keg->uk_align + 1;
1368 rsize = keg->uk_size;
1369 /*
1370 * We want one item to start on every align boundary in a page. To
1371 * do this we will span pages. We will also extend the item by the
1372 * size of align if it is an even multiple of align. Otherwise, it
1373 * would fall on the same boundary every time.
1374 */
1375 if (rsize & keg->uk_align)
1376 rsize = (rsize & ~keg->uk_align) + alignsize;
1377 if ((rsize & alignsize) == 0)
1378 rsize += alignsize;
1379 trailer = rsize - keg->uk_size;
1380 pages = (rsize * (PAGE_SIZE / alignsize)) / PAGE_SIZE;
1381 pages = MIN(pages, (128 * 1024) / PAGE_SIZE);
1382 keg->uk_rsize = rsize;
1383 keg->uk_ppera = pages;
1384 keg->uk_slabsize = UMA_SLAB_SIZE;
1385 keg->uk_ipers = ((pages * PAGE_SIZE) + trailer) / rsize;
1386 keg->uk_flags |= UMA_ZONE_OFFPAGE | UMA_ZONE_VTOSLAB;
1387 KASSERT(keg->uk_ipers <= SLAB_SETSIZE,
1388 ("%s: keg->uk_ipers too high(%d) increase max_ipers", __func__,
1389 keg->uk_ipers));
1390}
1391
1392/*
1393 * Keg header ctor. This initializes all fields, locks, etc. And inserts
1394 * the keg onto the global keg list.
1395 *
1396 * Arguments/Returns follow uma_ctor specifications
1397 * udata Actually uma_kctor_args
1398 */
1399static int
1400keg_ctor(void *mem, int size, void *udata, int flags)
1401{
1402 struct uma_kctor_args *arg = udata;
1403 uma_keg_t keg = mem;
1404 uma_zone_t zone;
1405
1406 bzero(keg, size);
1407 keg->uk_size = arg->size;
1408 keg->uk_init = arg->uminit;
1409 keg->uk_fini = arg->fini;
1410 keg->uk_align = arg->align;
1411 keg->uk_free = 0;
1412 keg->uk_reserve = 0;
1413 keg->uk_pages = 0;
1414 keg->uk_flags = arg->flags;
1415 keg->uk_allocf = page_alloc;
1416 keg->uk_freef = page_free;
1417 keg->uk_slabzone = NULL;
1418
1419 /*
1420 * The master zone is passed to us at keg-creation time.
1421 */
1422 zone = arg->zone;
1423 keg->uk_name = zone->uz_name;
1424
1425 if (arg->flags & UMA_ZONE_VM)
1426 keg->uk_flags |= UMA_ZFLAG_CACHEONLY;
1427
1428 if (arg->flags & UMA_ZONE_ZINIT)
1429 keg->uk_init = zero_init;
1430
1431 if (arg->flags & UMA_ZONE_MALLOC)
1432 keg->uk_flags |= UMA_ZONE_VTOSLAB;
1433
1434 if (arg->flags & UMA_ZONE_PCPU)
1435#ifdef SMP
1436 keg->uk_flags |= UMA_ZONE_OFFPAGE;
1437#else
1438 keg->uk_flags &= ~UMA_ZONE_PCPU;
1439#endif
1440
1441 if (keg->uk_flags & UMA_ZONE_CACHESPREAD) {
1442 keg_cachespread_init(keg);
1443 } else {
1444 if (keg->uk_size > (UMA_SLAB_SIZE - sizeof(struct uma_slab)))
1445 keg_large_init(keg);
1446 else
1447 keg_small_init(keg);
1448 }
1449
1450 if (keg->uk_flags & UMA_ZONE_OFFPAGE)
1451 keg->uk_slabzone = slabzone;
1452
1453 /*
1454 * If we haven't booted yet we need allocations to go through the
1455 * startup cache until the vm is ready.
1456 */
1457 if (keg->uk_ppera == 1) {
1458#ifdef UMA_MD_SMALL_ALLOC
1459 keg->uk_allocf = uma_small_alloc;
1460 keg->uk_freef = uma_small_free;
1461
1462 if (booted < UMA_STARTUP)
1463 keg->uk_allocf = startup_alloc;
1464#else
1465 if (booted < UMA_STARTUP2)
1466 keg->uk_allocf = startup_alloc;
1467#endif
1468 } else if (booted < UMA_STARTUP2 &&
1469 (keg->uk_flags & UMA_ZFLAG_INTERNAL))
1470 keg->uk_allocf = startup_alloc;
1471
1472 /*
1473 * Initialize keg's lock
1474 */
1475 KEG_LOCK_INIT(keg, (arg->flags & UMA_ZONE_MTXCLASS));
1476
1477 /*
1478 * If we're putting the slab header in the actual page we need to
1479 * figure out where in each page it goes. This calculates a right
1480 * justified offset into the memory on an ALIGN_PTR boundary.
1481 */
1482 if (!(keg->uk_flags & UMA_ZONE_OFFPAGE)) {
1483 u_int totsize;
1484
1485 /* Size of the slab struct and free list */
1486 totsize = sizeof(struct uma_slab);
1487
1488 if (totsize & UMA_ALIGN_PTR)
1489 totsize = (totsize & ~UMA_ALIGN_PTR) +
1490 (UMA_ALIGN_PTR + 1);
1491 keg->uk_pgoff = (PAGE_SIZE * keg->uk_ppera) - totsize;
1492
1493 /*
1494 * The only way the following is possible is if with our
1495 * UMA_ALIGN_PTR adjustments we are now bigger than
1496 * UMA_SLAB_SIZE. I haven't checked whether this is
1497 * mathematically possible for all cases, so we make
1498 * sure here anyway.
1499 */
1500 totsize = keg->uk_pgoff + sizeof(struct uma_slab);
1501 if (totsize > PAGE_SIZE * keg->uk_ppera) {
1502 printf("zone %s ipers %d rsize %d size %d\n",
1503 zone->uz_name, keg->uk_ipers, keg->uk_rsize,
1504 keg->uk_size);
1505 panic("UMA slab won't fit.");
1506 }
1507 }
1508
1509 if (keg->uk_flags & UMA_ZONE_HASH)
1510 hash_alloc(&keg->uk_hash);
1511
1512#ifdef UMA_DEBUG
1513 printf("UMA: %s(%p) size %d(%d) flags %#x ipers %d ppera %d out %d free %d\n",
1514 zone->uz_name, zone, keg->uk_size, keg->uk_rsize, keg->uk_flags,
1515 keg->uk_ipers, keg->uk_ppera,
1516 (keg->uk_ipers * keg->uk_pages) - keg->uk_free, keg->uk_free);
1517#endif
1518
1519 LIST_INSERT_HEAD(&keg->uk_zones, zone, uz_link);
1520
1521 rw_wlock(&uma_rwlock);
1522 LIST_INSERT_HEAD(&uma_kegs, keg, uk_link);
1523 rw_wunlock(&uma_rwlock);
1524 return (0);
1525}
1526
1527/*
1528 * Zone header ctor. This initializes all fields, locks, etc.
1529 *
1530 * Arguments/Returns follow uma_ctor specifications
1531 * udata Actually uma_zctor_args
1532 */
1533static int
1534zone_ctor(void *mem, int size, void *udata, int flags)
1535{
1536 struct uma_zctor_args *arg = udata;
1537 uma_zone_t zone = mem;
1538 uma_zone_t z;
1539 uma_keg_t keg;
1540
1541 bzero(zone, size);
1542 zone->uz_name = arg->name;
1543 zone->uz_ctor = arg->ctor;
1544 zone->uz_dtor = arg->dtor;
1545 zone->uz_slab = zone_fetch_slab;
1546 zone->uz_init = NULL;
1547 zone->uz_fini = NULL;
1548 zone->uz_allocs = 0;
1549 zone->uz_frees = 0;
1550 zone->uz_fails = 0;
1551 zone->uz_sleeps = 0;
1552 zone->uz_count = 0;
1553 zone->uz_count_min = 0;
1554 zone->uz_flags = 0;
1555 zone->uz_warning = NULL;
1556 timevalclear(&zone->uz_ratecheck);
1557 keg = arg->keg;
1558
1559 ZONE_LOCK_INIT(zone, (arg->flags & UMA_ZONE_MTXCLASS));
1560
1561 /*
1562 * This is a pure cache zone, no kegs.
1563 */
1564 if (arg->import) {
1565 if (arg->flags & UMA_ZONE_VM)
1566 arg->flags |= UMA_ZFLAG_CACHEONLY;
1567 zone->uz_flags = arg->flags;
1568 zone->uz_size = arg->size;
1569 zone->uz_import = arg->import;
1570 zone->uz_release = arg->release;
1571 zone->uz_arg = arg->arg;
1572 zone->uz_lockptr = &zone->uz_lock;
1573 rw_wlock(&uma_rwlock);
1574 LIST_INSERT_HEAD(&uma_cachezones, zone, uz_link);
1575 rw_wunlock(&uma_rwlock);
1576 goto out;
1577 }
1578
1579 /*
1580 * Use the regular zone/keg/slab allocator.
1581 */
1582 zone->uz_import = (uma_import)zone_import;
1583 zone->uz_release = (uma_release)zone_release;
1584 zone->uz_arg = zone;
1585
1586 if (arg->flags & UMA_ZONE_SECONDARY) {
1587 KASSERT(arg->keg != NULL, ("Secondary zone on zero'd keg"));
1588 zone->uz_init = arg->uminit;
1589 zone->uz_fini = arg->fini;
1590 zone->uz_lockptr = &keg->uk_lock;
1591 zone->uz_flags |= UMA_ZONE_SECONDARY;
1592 rw_wlock(&uma_rwlock);
1593 ZONE_LOCK(zone);
1594 LIST_FOREACH(z, &keg->uk_zones, uz_link) {
1595 if (LIST_NEXT(z, uz_link) == NULL) {
1596 LIST_INSERT_AFTER(z, zone, uz_link);
1597 break;
1598 }
1599 }
1600 ZONE_UNLOCK(zone);
1601 rw_wunlock(&uma_rwlock);
1602 } else if (keg == NULL) {
1603 if ((keg = uma_kcreate(zone, arg->size, arg->uminit, arg->fini,
1604 arg->align, arg->flags)) == NULL)
1605 return (ENOMEM);
1606 } else {
1607 struct uma_kctor_args karg;
1608 int error;
1609
1610 /* We should only be here from uma_startup() */
1611 karg.size = arg->size;
1612 karg.uminit = arg->uminit;
1613 karg.fini = arg->fini;
1614 karg.align = arg->align;
1615 karg.flags = arg->flags;
1616 karg.zone = zone;
1617 error = keg_ctor(arg->keg, sizeof(struct uma_keg), &karg,
1618 flags);
1619 if (error)
1620 return (error);
1621 }
1622
1623 /*
1624 * Link in the first keg.
1625 */
1626 zone->uz_klink.kl_keg = keg;
1627 LIST_INSERT_HEAD(&zone->uz_kegs, &zone->uz_klink, kl_link);
1628 zone->uz_lockptr = &keg->uk_lock;
1629 zone->uz_size = keg->uk_size;
1630 zone->uz_flags |= (keg->uk_flags &
1631 (UMA_ZONE_INHERIT | UMA_ZFLAG_INHERIT));
1632
1633 /*
1634 * Some internal zones don't have room allocated for the per cpu
1635 * caches. If we're internal, bail out here.
1636 */
1637 if (keg->uk_flags & UMA_ZFLAG_INTERNAL) {
1638 KASSERT((zone->uz_flags & UMA_ZONE_SECONDARY) == 0,
1639 ("Secondary zone requested UMA_ZFLAG_INTERNAL"));
1640 return (0);
1641 }
1642
1643out:
1644 if ((arg->flags & UMA_ZONE_MAXBUCKET) == 0)
1645 zone->uz_count = bucket_select(zone->uz_size);
1646 else
1647 zone->uz_count = BUCKET_MAX;
1648 zone->uz_count_min = zone->uz_count;
1649
1650 return (0);
1651}
1652
1653/*
1654 * Keg header dtor. This frees all data, destroys locks, frees the hash
1655 * table and removes the keg from the global list.
1656 *
1657 * Arguments/Returns follow uma_dtor specifications
1658 * udata unused
1659 */
1660static void
1661keg_dtor(void *arg, int size, void *udata)
1662{
1663 uma_keg_t keg;
1664
1665 keg = (uma_keg_t)arg;
1666 KEG_LOCK(keg);
1667 if (keg->uk_free != 0) {
1668 printf("Freed UMA keg (%s) was not empty (%d items). "
1669 " Lost %d pages of memory.\n",
1670 keg->uk_name ? keg->uk_name : "",
1671 keg->uk_free, keg->uk_pages);
1672 }
1673 KEG_UNLOCK(keg);
1674
1675 hash_free(&keg->uk_hash);
1676
1677 KEG_LOCK_FINI(keg);
1678}
1679
1680/*
1681 * Zone header dtor.
1682 *
1683 * Arguments/Returns follow uma_dtor specifications
1684 * udata unused
1685 */
1686static void
1687zone_dtor(void *arg, int size, void *udata)
1688{
1689 uma_klink_t klink;
1690 uma_zone_t zone;
1691 uma_keg_t keg;
1692
1693 zone = (uma_zone_t)arg;
1694 keg = zone_first_keg(zone);
1695
1696 if (!(zone->uz_flags & UMA_ZFLAG_INTERNAL))
1697 cache_drain(zone);
1698
1699 rw_wlock(&uma_rwlock);
1700 LIST_REMOVE(zone, uz_link);
1701 rw_wunlock(&uma_rwlock);
1702 /*
1703 * XXX there are some races here where
1704 * the zone can be drained but zone lock
1705 * released and then refilled before we
1706 * remove it... we dont care for now
1707 */
1708 zone_drain_wait(zone, M_WAITOK);
1709 /*
1710 * Unlink all of our kegs.
1711 */
1712 while ((klink = LIST_FIRST(&zone->uz_kegs)) != NULL) {
1713 klink->kl_keg = NULL;
1714 LIST_REMOVE(klink, kl_link);
1715 if (klink == &zone->uz_klink)
1716 continue;
1717 free(klink, M_TEMP);
1718 }
1719 /*
1720 * We only destroy kegs from non secondary zones.
1721 */
1722 if (keg != NULL && (zone->uz_flags & UMA_ZONE_SECONDARY) == 0) {
1723 rw_wlock(&uma_rwlock);
1724 LIST_REMOVE(keg, uk_link);
1725 rw_wunlock(&uma_rwlock);
1726 zone_free_item(kegs, keg, NULL, SKIP_NONE);
1727 }
1728 ZONE_LOCK_FINI(zone);
1729}
1730
1731/*
1732 * Traverses every zone in the system and calls a callback
1733 *
1734 * Arguments:
1735 * zfunc A pointer to a function which accepts a zone
1736 * as an argument.
1737 *
1738 * Returns:
1739 * Nothing
1740 */
1741static void
1742zone_foreach(void (*zfunc)(uma_zone_t))
1743{
1744 uma_keg_t keg;
1745 uma_zone_t zone;
1746
1747 rw_rlock(&uma_rwlock);
1748 LIST_FOREACH(keg, &uma_kegs, uk_link) {
1749 LIST_FOREACH(zone, &keg->uk_zones, uz_link)
1750 zfunc(zone);
1751 }
1752 rw_runlock(&uma_rwlock);
1753}
1754
1755/* Public functions */
1756/* See uma.h */
1757void
1758uma_startup(void *bootmem, int boot_pages)
1759{
1760 struct uma_zctor_args args;
1761 uma_slab_t slab;
1762 int i;
1763
1764#ifdef UMA_DEBUG
1765 printf("Creating uma keg headers zone and keg.\n");
1766#endif
1767 rw_init(&uma_rwlock, "UMA lock");
1768
1769 /* "manually" create the initial zone */
1770 memset(&args, 0, sizeof(args));
1771 args.name = "UMA Kegs";
1772 args.size = sizeof(struct uma_keg);
1773 args.ctor = keg_ctor;
1774 args.dtor = keg_dtor;
1775 args.uminit = zero_init;
1776 args.fini = NULL;
1777 args.keg = &masterkeg;
1778 args.align = 32 - 1;
1779 args.flags = UMA_ZFLAG_INTERNAL;
1780 /* The initial zone has no Per cpu queues so it's smaller */
1781 zone_ctor(kegs, sizeof(struct uma_zone), &args, M_WAITOK);
1782
1783#ifdef UMA_DEBUG
1784 printf("Filling boot free list.\n");
1785#endif
1786 for (i = 0; i < boot_pages; i++) {
1787 slab = (uma_slab_t)((uint8_t *)bootmem + (i * UMA_SLAB_SIZE));
1788 slab->us_data = (uint8_t *)slab;
1789 slab->us_flags = UMA_SLAB_BOOT;
1790 LIST_INSERT_HEAD(&uma_boot_pages, slab, us_link);
1791 }
1792 mtx_init(&uma_boot_pages_mtx, "UMA boot pages", NULL, MTX_DEF);
1793
1794#ifdef UMA_DEBUG
1795 printf("Creating uma zone headers zone and keg.\n");
1796#endif
1797 args.name = "UMA Zones";
1798 args.size = sizeof(struct uma_zone) +
1799 (sizeof(struct uma_cache) * (mp_maxid + 1));
1800 args.ctor = zone_ctor;
1801 args.dtor = zone_dtor;
1802 args.uminit = zero_init;
1803 args.fini = NULL;
1804 args.keg = NULL;
1805 args.align = 32 - 1;
1806 args.flags = UMA_ZFLAG_INTERNAL;
1807 /* The initial zone has no Per cpu queues so it's smaller */
1808 zone_ctor(zones, sizeof(struct uma_zone), &args, M_WAITOK);
1809
1810#ifdef UMA_DEBUG
1811 printf("Creating slab and hash zones.\n");
1812#endif
1813
1814 /* Now make a zone for slab headers */
1815 slabzone = uma_zcreate("UMA Slabs",
1816 sizeof(struct uma_slab),
1817 NULL, NULL, NULL, NULL,
1818 UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
1819
1820 hashzone = uma_zcreate("UMA Hash",
1821 sizeof(struct slabhead *) * UMA_HASH_SIZE_INIT,
1822 NULL, NULL, NULL, NULL,
1823 UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
1824
1825 bucket_init();
1826
1827 booted = UMA_STARTUP;
1828
1829#ifdef UMA_DEBUG
1830 printf("UMA startup complete.\n");
1831#endif
1832}
1833
1834/* see uma.h */
1835void
1836uma_startup2(void)
1837{
1838 booted = UMA_STARTUP2;
1839 bucket_enable();
1840 sx_init(&uma_drain_lock, "umadrain");
1841#ifdef UMA_DEBUG
1842 printf("UMA startup2 complete.\n");
1843#endif
1844}
1845
1846/*
1847 * Initialize our callout handle
1848 *
1849 */
1850
1851static void
1852uma_startup3(void)
1853{
1854#ifdef UMA_DEBUG
1855 printf("Starting callout.\n");
1856#endif
1857 callout_init(&uma_callout, 1);
1858 callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL);
1859#ifdef UMA_DEBUG
1860 printf("UMA startup3 complete.\n");
1861#endif
1862}
1863
1864static uma_keg_t
1865uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit, uma_fini fini,
1866 int align, uint32_t flags)
1867{
1868 struct uma_kctor_args args;
1869
1870 args.size = size;
1871 args.uminit = uminit;
1872 args.fini = fini;
1873 args.align = (align == UMA_ALIGN_CACHE) ? uma_align_cache : align;
1874 args.flags = flags;
1875 args.zone = zone;
1876 return (zone_alloc_item(kegs, &args, M_WAITOK));
1877}
1878
1879/* See uma.h */
1880void
1881uma_set_align(int align)
1882{
1883
1884 if (align != UMA_ALIGN_CACHE)
1885 uma_align_cache = align;
1886}
1887
1888/* See uma.h */
1889uma_zone_t
1890uma_zcreate(const char *name, size_t size, uma_ctor ctor, uma_dtor dtor,
1891 uma_init uminit, uma_fini fini, int align, uint32_t flags)
1892
1893{
1894 struct uma_zctor_args args;
1895 uma_zone_t res;
1896 bool locked;
1897
1898 /* This stuff is essential for the zone ctor */
1899 memset(&args, 0, sizeof(args));
1900 args.name = name;
1901 args.size = size;
1902 args.ctor = ctor;
1903 args.dtor = dtor;
1904 args.uminit = uminit;
1905 args.fini = fini;
1906#ifdef INVARIANTS
1907 /*
1908 * If a zone is being created with an empty constructor and
1909 * destructor, pass UMA constructor/destructor which checks for
1910 * memory use after free.
1911 */
1912 if ((!(flags & (UMA_ZONE_ZINIT | UMA_ZONE_NOFREE))) &&
1913 ctor == NULL && dtor == NULL && uminit == NULL && fini == NULL) {
1914 args.ctor = trash_ctor;
1915 args.dtor = trash_dtor;
1916 args.uminit = trash_init;
1917 args.fini = trash_fini;
1918 }
1919#endif
1920 args.align = align;
1921 args.flags = flags;
1922 args.keg = NULL;
1923
1924 if (booted < UMA_STARTUP2) {
1925 locked = false;
1926 } else {
1927 sx_slock(&uma_drain_lock);
1928 locked = true;
1929 }
1930 res = zone_alloc_item(zones, &args, M_WAITOK);
1931 if (locked)
1932 sx_sunlock(&uma_drain_lock);
1933 return (res);
1934}
1935
1936/* See uma.h */
1937uma_zone_t
1938uma_zsecond_create(char *name, uma_ctor ctor, uma_dtor dtor,
1939 uma_init zinit, uma_fini zfini, uma_zone_t master)
1940{
1941 struct uma_zctor_args args;
1942 uma_keg_t keg;
1943 uma_zone_t res;
1944 bool locked;
1945
1946 keg = zone_first_keg(master);
1947 memset(&args, 0, sizeof(args));
1948 args.name = name;
1949 args.size = keg->uk_size;
1950 args.ctor = ctor;
1951 args.dtor = dtor;
1952 args.uminit = zinit;
1953 args.fini = zfini;
1954 args.align = keg->uk_align;
1955 args.flags = keg->uk_flags | UMA_ZONE_SECONDARY;
1956 args.keg = keg;
1957
1958 if (booted < UMA_STARTUP2) {
1959 locked = false;
1960 } else {
1961 sx_slock(&uma_drain_lock);
1962 locked = true;
1963 }
1964 /* XXX Attaches only one keg of potentially many. */
1965 res = zone_alloc_item(zones, &args, M_WAITOK);
1966 if (locked)
1967 sx_sunlock(&uma_drain_lock);
1968 return (res);
1969}
1970
1971/* See uma.h */
1972uma_zone_t
1973uma_zcache_create(char *name, int size, uma_ctor ctor, uma_dtor dtor,
1974 uma_init zinit, uma_fini zfini, uma_import zimport,
1975 uma_release zrelease, void *arg, int flags)
1976{
1977 struct uma_zctor_args args;
1978
1979 memset(&args, 0, sizeof(args));
1980 args.name = name;
1981 args.size = size;
1982 args.ctor = ctor;
1983 args.dtor = dtor;
1984 args.uminit = zinit;
1985 args.fini = zfini;
1986 args.import = zimport;
1987 args.release = zrelease;
1988 args.arg = arg;
1989 args.align = 0;
1990 args.flags = flags;
1991
1992 return (zone_alloc_item(zones, &args, M_WAITOK));
1993}
1994
1995static void
1996zone_lock_pair(uma_zone_t a, uma_zone_t b)
1997{
1998 if (a < b) {
1999 ZONE_LOCK(a);
2000 mtx_lock_flags(b->uz_lockptr, MTX_DUPOK);
2001 } else {
2002 ZONE_LOCK(b);
2003 mtx_lock_flags(a->uz_lockptr, MTX_DUPOK);
2004 }
2005}
2006
2007static void
2008zone_unlock_pair(uma_zone_t a, uma_zone_t b)
2009{
2010
2011 ZONE_UNLOCK(a);
2012 ZONE_UNLOCK(b);
2013}
2014
2015int
2016uma_zsecond_add(uma_zone_t zone, uma_zone_t master)
2017{
2018 uma_klink_t klink;
2019 uma_klink_t kl;
2020 int error;
2021
2022 error = 0;
2023 klink = malloc(sizeof(*klink), M_TEMP, M_WAITOK | M_ZERO);
2024
2025 zone_lock_pair(zone, master);
2026 /*
2027 * zone must use vtoslab() to resolve objects and must already be
2028 * a secondary.
2029 */
2030 if ((zone->uz_flags & (UMA_ZONE_VTOSLAB | UMA_ZONE_SECONDARY))
2031 != (UMA_ZONE_VTOSLAB | UMA_ZONE_SECONDARY)) {
2032 error = EINVAL;
2033 goto out;
2034 }
2035 /*
2036 * The new master must also use vtoslab().
2037 */
2038 if ((zone->uz_flags & UMA_ZONE_VTOSLAB) != UMA_ZONE_VTOSLAB) {
2039 error = EINVAL;
2040 goto out;
2041 }
2042
2043 /*
2044 * The underlying object must be the same size. rsize
2045 * may be different.
2046 */
2047 if (master->uz_size != zone->uz_size) {
2048 error = E2BIG;
2049 goto out;
2050 }
2051 /*
2052 * Put it at the end of the list.
2053 */
2054 klink->kl_keg = zone_first_keg(master);
2055 LIST_FOREACH(kl, &zone->uz_kegs, kl_link) {
2056 if (LIST_NEXT(kl, kl_link) == NULL) {
2057 LIST_INSERT_AFTER(kl, klink, kl_link);
2058 break;
2059 }
2060 }
2061 klink = NULL;
2062 zone->uz_flags |= UMA_ZFLAG_MULTI;
2063 zone->uz_slab = zone_fetch_slab_multi;
2064
2065out:
2066 zone_unlock_pair(zone, master);
2067 if (klink != NULL)
2068 free(klink, M_TEMP);
2069
2070 return (error);
2071}
2072
2073
2074/* See uma.h */
2075void
2076uma_zdestroy(uma_zone_t zone)
2077{
2078
2079 sx_slock(&uma_drain_lock);
2080 zone_free_item(zones, zone, NULL, SKIP_NONE);
2081 sx_sunlock(&uma_drain_lock);
2082}
2083
2084/* See uma.h */
2085void *
2086uma_zalloc_arg(uma_zone_t zone, void *udata, int flags)
2087{
2088 void *item;
2089 uma_cache_t cache;
2090 uma_bucket_t bucket;
2091 int lockfail;
2092 int cpu;
2093
2094 /* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
2095 random_harvest_fast_uma(&zone, sizeof(zone), 1, RANDOM_UMA);
2096
2097 /* This is the fast path allocation */
2098#ifdef UMA_DEBUG_ALLOC_1
2099 printf("Allocating one item from %s(%p)\n", zone->uz_name, zone);
2100#endif
2101 CTR3(KTR_UMA, "uma_zalloc_arg thread %x zone %s flags %d", curthread,
2102 zone->uz_name, flags);
2103
2104 if (flags & M_WAITOK) {
2105 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
2106 "uma_zalloc_arg: zone \"%s\"", zone->uz_name);
2107 }
2108 KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
2109 ("uma_zalloc_arg: called with spinlock or critical section held"));
2110
2111#ifdef DEBUG_MEMGUARD
2112 if (memguard_cmp_zone(zone)) {
2113 item = memguard_alloc(zone->uz_size, flags);
2114 if (item != NULL) {
2115 if (zone->uz_init != NULL &&
2116 zone->uz_init(item, zone->uz_size, flags) != 0)
2117 return (NULL);
2118 if (zone->uz_ctor != NULL &&
2119 zone->uz_ctor(item, zone->uz_size, udata,
2120 flags) != 0) {
2121 zone->uz_fini(item, zone->uz_size);
2122 return (NULL);
2123 }
2124 return (item);
2125 }
2126 /* This is unfortunate but should not be fatal. */
2127 }
2128#endif
2129 /*
2130 * If possible, allocate from the per-CPU cache. There are two
2131 * requirements for safe access to the per-CPU cache: (1) the thread
2132 * accessing the cache must not be preempted or yield during access,
2133 * and (2) the thread must not migrate CPUs without switching which
2134 * cache it accesses. We rely on a critical section to prevent
2135 * preemption and migration. We release the critical section in
2136 * order to acquire the zone mutex if we are unable to allocate from
2137 * the current cache; when we re-acquire the critical section, we
2138 * must detect and handle migration if it has occurred.
2139 */
2140 critical_enter();
2141 cpu = curcpu;
2142 cache = &zone->uz_cpu[cpu];
2143
2144zalloc_start:
2145 bucket = cache->uc_allocbucket;
2146 if (bucket != NULL && bucket->ub_cnt > 0) {
2147 bucket->ub_cnt--;
2148 item = bucket->ub_bucket[bucket->ub_cnt];
2149#ifdef INVARIANTS
2150 bucket->ub_bucket[bucket->ub_cnt] = NULL;
2151#endif
2152 KASSERT(item != NULL, ("uma_zalloc: Bucket pointer mangled."));
2153 cache->uc_allocs++;
2154 critical_exit();
2155 if (zone->uz_ctor != NULL &&
2156 zone->uz_ctor(item, zone->uz_size, udata, flags) != 0) {
2157 atomic_add_long(&zone->uz_fails, 1);
2158 zone_free_item(zone, item, udata, SKIP_DTOR);
2159 return (NULL);
2160 }
2161#ifdef INVARIANTS
2162 uma_dbg_alloc(zone, NULL, item);
2163#endif
2164 if (flags & M_ZERO)
2165 uma_zero_item(item, zone);
2166 return (item);
2167 }
2168
2169 /*
2170 * We have run out of items in our alloc bucket.
2171 * See if we can switch with our free bucket.
2172 */
2173 bucket = cache->uc_freebucket;
2174 if (bucket != NULL && bucket->ub_cnt > 0) {
2175#ifdef UMA_DEBUG_ALLOC
2176 printf("uma_zalloc: Swapping empty with alloc.\n");
2177#endif
2178 cache->uc_freebucket = cache->uc_allocbucket;
2179 cache->uc_allocbucket = bucket;
2180 goto zalloc_start;
2181 }
2182
2183 /*
2184 * Discard any empty allocation bucket while we hold no locks.
2185 */
2186 bucket = cache->uc_allocbucket;
2187 cache->uc_allocbucket = NULL;
2188 critical_exit();
2189 if (bucket != NULL)
2190 bucket_free(zone, bucket, udata);
2191
2192 /* Short-circuit for zones without buckets and low memory. */
2193 if (zone->uz_count == 0 || bucketdisable)
2194 goto zalloc_item;
2195
2196 /*
2197 * Attempt to retrieve the item from the per-CPU cache has failed, so
2198 * we must go back to the zone. This requires the zone lock, so we
2199 * must drop the critical section, then re-acquire it when we go back
2200 * to the cache. Since the critical section is released, we may be
2201 * preempted or migrate. As such, make sure not to maintain any
2202 * thread-local state specific to the cache from prior to releasing
2203 * the critical section.
2204 */
2205 lockfail = 0;
2206 if (ZONE_TRYLOCK(zone) == 0) {
2207 /* Record contention to size the buckets. */
2208 ZONE_LOCK(zone);
2209 lockfail = 1;
2210 }
2211 critical_enter();
2212 cpu = curcpu;
2213 cache = &zone->uz_cpu[cpu];
2214
2215 /*
2216 * Since we have locked the zone we may as well send back our stats.
2217 */
2218 atomic_add_long(&zone->uz_allocs, cache->uc_allocs);
2219 atomic_add_long(&zone->uz_frees, cache->uc_frees);
2220 cache->uc_allocs = 0;
2221 cache->uc_frees = 0;
2222
2223 /* See if we lost the race to fill the cache. */
2224 if (cache->uc_allocbucket != NULL) {
2225 ZONE_UNLOCK(zone);
2226 goto zalloc_start;
2227 }
2228
2229 /*
2230 * Check the zone's cache of buckets.
2231 */
2232 if ((bucket = LIST_FIRST(&zone->uz_buckets)) != NULL) {
2233 KASSERT(bucket->ub_cnt != 0,
2234 ("uma_zalloc_arg: Returning an empty bucket."));
2235
2236 LIST_REMOVE(bucket, ub_link);
2237 cache->uc_allocbucket = bucket;
2238 ZONE_UNLOCK(zone);
2239 goto zalloc_start;
2240 }
2241 /* We are no longer associated with this CPU. */
2242 critical_exit();
2243
2244 /*
2245 * We bump the uz count when the cache size is insufficient to
2246 * handle the working set.
2247 */
2248 if (lockfail && zone->uz_count < BUCKET_MAX)
2249 zone->uz_count++;
2250 ZONE_UNLOCK(zone);
2251
2252 /*
2253 * Now lets just fill a bucket and put it on the free list. If that
2254 * works we'll restart the allocation from the beginning and it
2255 * will use the just filled bucket.
2256 */
2257 bucket = zone_alloc_bucket(zone, udata, flags);
2258 if (bucket != NULL) {
2259 ZONE_LOCK(zone);
2260 critical_enter();
2261 cpu = curcpu;
2262 cache = &zone->uz_cpu[cpu];
2263 /*
2264 * See if we lost the race or were migrated. Cache the
2265 * initialized bucket to make this less likely or claim
2266 * the memory directly.
2267 */
2268 if (cache->uc_allocbucket == NULL)
2269 cache->uc_allocbucket = bucket;
2270 else
2271 LIST_INSERT_HEAD(&zone->uz_buckets, bucket, ub_link);
2272 ZONE_UNLOCK(zone);
2273 goto zalloc_start;
2274 }
2275
2276 /*
2277 * We may not be able to get a bucket so return an actual item.
2278 */
2279#ifdef UMA_DEBUG
2280 printf("uma_zalloc_arg: Bucketzone returned NULL\n");
2281#endif
2282
2283zalloc_item:
2284 item = zone_alloc_item(zone, udata, flags);
2285
2286 return (item);
2287}
2288
2289static uma_slab_t
2290keg_fetch_slab(uma_keg_t keg, uma_zone_t zone, int flags)
2291{
2292 uma_slab_t slab;
2293 int reserve;
2294
2295 mtx_assert(&keg->uk_lock, MA_OWNED);
2296 slab = NULL;
2297 reserve = 0;
2298 if ((flags & M_USE_RESERVE) == 0)
2299 reserve = keg->uk_reserve;
2300
2301 for (;;) {
2302 /*
2303 * Find a slab with some space. Prefer slabs that are partially
2304 * used over those that are totally full. This helps to reduce
2305 * fragmentation.
2306 */
2307 if (keg->uk_free > reserve) {
2308 if (!LIST_EMPTY(&keg->uk_part_slab)) {
2309 slab = LIST_FIRST(&keg->uk_part_slab);
2310 } else {
2311 slab = LIST_FIRST(&keg->uk_free_slab);
2312 LIST_REMOVE(slab, us_link);
2313 LIST_INSERT_HEAD(&keg->uk_part_slab, slab,
2314 us_link);
2315 }
2316 MPASS(slab->us_keg == keg);
2317 return (slab);
2318 }
2319
2320 /*
2321 * M_NOVM means don't ask at all!
2322 */
2323 if (flags & M_NOVM)
2324 break;
2325
2326 if (keg->uk_maxpages && keg->uk_pages >= keg->uk_maxpages) {
2327 keg->uk_flags |= UMA_ZFLAG_FULL;
2328 /*
2329 * If this is not a multi-zone, set the FULL bit.
2330 * Otherwise slab_multi() takes care of it.
2331 */
2332 if ((zone->uz_flags & UMA_ZFLAG_MULTI) == 0) {
2333 zone->uz_flags |= UMA_ZFLAG_FULL;
2334 zone_log_warning(zone);
2335 zone_maxaction(zone);
2336 }
2337 if (flags & M_NOWAIT)
2338 break;
2339 zone->uz_sleeps++;
2340 msleep(keg, &keg->uk_lock, PVM, "keglimit", 0);
2341 continue;
2342 }
2343 slab = keg_alloc_slab(keg, zone, flags);
2344 /*
2345 * If we got a slab here it's safe to mark it partially used
2346 * and return. We assume that the caller is going to remove
2347 * at least one item.
2348 */
2349 if (slab) {
2350 MPASS(slab->us_keg == keg);
2351 LIST_INSERT_HEAD(&keg->uk_part_slab, slab, us_link);
2352 return (slab);
2353 }
2354 /*
2355 * We might not have been able to get a slab but another cpu
2356 * could have while we were unlocked. Check again before we
2357 * fail.
2358 */
2359 flags |= M_NOVM;
2360 }
2361 return (slab);
2362}
2363
2364static uma_slab_t
2365zone_fetch_slab(uma_zone_t zone, uma_keg_t keg, int flags)
2366{
2367 uma_slab_t slab;
2368
2369 if (keg == NULL) {
2370 keg = zone_first_keg(zone);
2371 KEG_LOCK(keg);
2372 }
2373
2374 for (;;) {
2375 slab = keg_fetch_slab(keg, zone, flags);
2376 if (slab)
2377 return (slab);
2378 if (flags & (M_NOWAIT | M_NOVM))
2379 break;
2380 }
2381 KEG_UNLOCK(keg);
2382 return (NULL);
2383}
2384
2385/*
2386 * uma_zone_fetch_slab_multi: Fetches a slab from one available keg. Returns
2387 * with the keg locked. On NULL no lock is held.
2388 *
2389 * The last pointer is used to seed the search. It is not required.
2390 */
2391static uma_slab_t
2392zone_fetch_slab_multi(uma_zone_t zone, uma_keg_t last, int rflags)
2393{
2394 uma_klink_t klink;
2395 uma_slab_t slab;
2396 uma_keg_t keg;
2397 int flags;
2398 int empty;
2399 int full;
2400
2401 /*
2402 * Don't wait on the first pass. This will skip limit tests
2403 * as well. We don't want to block if we can find a provider
2404 * without blocking.
2405 */
2406 flags = (rflags & ~M_WAITOK) | M_NOWAIT;
2407 /*
2408 * Use the last slab allocated as a hint for where to start
2409 * the search.
2410 */
2411 if (last != NULL) {
2412 slab = keg_fetch_slab(last, zone, flags);
2413 if (slab)
2414 return (slab);
2415 KEG_UNLOCK(last);
2416 }
2417 /*
2418 * Loop until we have a slab incase of transient failures
2419 * while M_WAITOK is specified. I'm not sure this is 100%
2420 * required but we've done it for so long now.
2421 */
2422 for (;;) {
2423 empty = 0;
2424 full = 0;
2425 /*
2426 * Search the available kegs for slabs. Be careful to hold the
2427 * correct lock while calling into the keg layer.
2428 */
2429 LIST_FOREACH(klink, &zone->uz_kegs, kl_link) {
2430 keg = klink->kl_keg;
2431 KEG_LOCK(keg);
2432 if ((keg->uk_flags & UMA_ZFLAG_FULL) == 0) {
2433 slab = keg_fetch_slab(keg, zone, flags);
2434 if (slab)
2435 return (slab);
2436 }
2437 if (keg->uk_flags & UMA_ZFLAG_FULL)
2438 full++;
2439 else
2440 empty++;
2441 KEG_UNLOCK(keg);
2442 }
2443 if (rflags & (M_NOWAIT | M_NOVM))
2444 break;
2445 flags = rflags;
2446 /*
2447 * All kegs are full. XXX We can't atomically check all kegs
2448 * and sleep so just sleep for a short period and retry.
2449 */
2450 if (full && !empty) {
2451 ZONE_LOCK(zone);
2452 zone->uz_flags |= UMA_ZFLAG_FULL;
2453 zone->uz_sleeps++;
2454 zone_log_warning(zone);
2455 zone_maxaction(zone);
2456 msleep(zone, zone->uz_lockptr, PVM,
2457 "zonelimit", hz/100);
2458 zone->uz_flags &= ~UMA_ZFLAG_FULL;
2459 ZONE_UNLOCK(zone);
2460 continue;
2461 }
2462 }
2463 return (NULL);
2464}
2465
2466static void *
2467slab_alloc_item(uma_keg_t keg, uma_slab_t slab)
2468{
2469 void *item;
2470 uint8_t freei;
2471
2472 MPASS(keg == slab->us_keg);
2473 mtx_assert(&keg->uk_lock, MA_OWNED);
2474
2475 freei = BIT_FFS(SLAB_SETSIZE, &slab->us_free) - 1;
2476 BIT_CLR(SLAB_SETSIZE, freei, &slab->us_free);
2477 item = slab->us_data + (keg->uk_rsize * freei);
2478 slab->us_freecount--;
2479 keg->uk_free--;
2480
2481 /* Move this slab to the full list */
2482 if (slab->us_freecount == 0) {
2483 LIST_REMOVE(slab, us_link);
2484 LIST_INSERT_HEAD(&keg->uk_full_slab, slab, us_link);
2485 }
2486
2487 return (item);
2488}
2489
2490static int
2491zone_import(uma_zone_t zone, void **bucket, int max, int flags)
2492{
2493 uma_slab_t slab;
2494 uma_keg_t keg;
2495 int i;
2496
2497 slab = NULL;
2498 keg = NULL;
2499 /* Try to keep the buckets totally full */
2500 for (i = 0; i < max; ) {
2501 if ((slab = zone->uz_slab(zone, keg, flags)) == NULL)
2502 break;
2503 keg = slab->us_keg;
2504 while (slab->us_freecount && i < max) {
2505 bucket[i++] = slab_alloc_item(keg, slab);
2506 if (keg->uk_free <= keg->uk_reserve)
2507 break;
2508 }
2509 /* Don't grab more than one slab at a time. */
2510 flags &= ~M_WAITOK;
2511 flags |= M_NOWAIT;
2512 }
2513 if (slab != NULL)
2514 KEG_UNLOCK(keg);
2515
2516 return i;
2517}
2518
2519static uma_bucket_t
2520zone_alloc_bucket(uma_zone_t zone, void *udata, int flags)
2521{
2522 uma_bucket_t bucket;
2523 int max;
2524
2525 /* Don't wait for buckets, preserve caller's NOVM setting. */
2526 bucket = bucket_alloc(zone, udata, M_NOWAIT | (flags & M_NOVM));
2527 if (bucket == NULL)
2528 return (NULL);
2529
2530 max = MIN(bucket->ub_entries, zone->uz_count);
2531 bucket->ub_cnt = zone->uz_import(zone->uz_arg, bucket->ub_bucket,
2532 max, flags);
2533
2534 /*
2535 * Initialize the memory if necessary.
2536 */
2537 if (bucket->ub_cnt != 0 && zone->uz_init != NULL) {
2538 int i;
2539
2540 for (i = 0; i < bucket->ub_cnt; i++)
2541 if (zone->uz_init(bucket->ub_bucket[i], zone->uz_size,
2542 flags) != 0)
2543 break;
2544 /*
2545 * If we couldn't initialize the whole bucket, put the
2546 * rest back onto the freelist.
2547 */
2548 if (i != bucket->ub_cnt) {
2549 zone->uz_release(zone->uz_arg, &bucket->ub_bucket[i],
2550 bucket->ub_cnt - i);
2551#ifdef INVARIANTS
2552 bzero(&bucket->ub_bucket[i],
2553 sizeof(void *) * (bucket->ub_cnt - i));
2554#endif
2555 bucket->ub_cnt = i;
2556 }
2557 }
2558
2559 if (bucket->ub_cnt == 0) {
2560 bucket_free(zone, bucket, udata);
2561 atomic_add_long(&zone->uz_fails, 1);
2562 return (NULL);
2563 }
2564
2565 return (bucket);
2566}
2567
2568/*
2569 * Allocates a single item from a zone.
2570 *
2571 * Arguments
2572 * zone The zone to alloc for.
2573 * udata The data to be passed to the constructor.
2574 * flags M_WAITOK, M_NOWAIT, M_ZERO.
2575 *
2576 * Returns
2577 * NULL if there is no memory and M_NOWAIT is set
2578 * An item if successful
2579 */
2580
2581static void *
2582zone_alloc_item(uma_zone_t zone, void *udata, int flags)
2583{
2584 void *item;
2585
2586 item = NULL;
2587
2588#ifdef UMA_DEBUG_ALLOC
2589 printf("INTERNAL: Allocating one item from %s(%p)\n", zone->uz_name, zone);
2590#endif
2591 if (zone->uz_import(zone->uz_arg, &item, 1, flags) != 1)
2592 goto fail;
2593 atomic_add_long(&zone->uz_allocs, 1);
2594
2595 /*
2596 * We have to call both the zone's init (not the keg's init)
2597 * and the zone's ctor. This is because the item is going from
2598 * a keg slab directly to the user, and the user is expecting it
2599 * to be both zone-init'd as well as zone-ctor'd.
2600 */
2601 if (zone->uz_init != NULL) {
2602 if (zone->uz_init(item, zone->uz_size, flags) != 0) {
2603 zone_free_item(zone, item, udata, SKIP_FINI);
2604 goto fail;
2605 }
2606 }
2607 if (zone->uz_ctor != NULL) {
2608 if (zone->uz_ctor(item, zone->uz_size, udata, flags) != 0) {
2609 zone_free_item(zone, item, udata, SKIP_DTOR);
2610 goto fail;
2611 }
2612 }
2613#ifdef INVARIANTS
2614 uma_dbg_alloc(zone, NULL, item);
2615#endif
2616 if (flags & M_ZERO)
2617 uma_zero_item(item, zone);
2618
2619 return (item);
2620
2621fail:
2622 atomic_add_long(&zone->uz_fails, 1);
2623 return (NULL);
2624}
2625
2626/* See uma.h */
2627void
2628uma_zfree_arg(uma_zone_t zone, void *item, void *udata)
2629{
2630 uma_cache_t cache;
2631 uma_bucket_t bucket;
2632 int lockfail;
2633 int cpu;
2634
2635 /* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
2636 random_harvest_fast_uma(&zone, sizeof(zone), 1, RANDOM_UMA);
2637
2638#ifdef UMA_DEBUG_ALLOC_1
2639 printf("Freeing item %p to %s(%p)\n", item, zone->uz_name, zone);
2640#endif
2641 CTR2(KTR_UMA, "uma_zfree_arg thread %x zone %s", curthread,
2642 zone->uz_name);
2643
2644 KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
2645 ("uma_zfree_arg: called with spinlock or critical section held"));
2646
2647 /* uma_zfree(..., NULL) does nothing, to match free(9). */
2648 if (item == NULL)
2649 return;
2650#ifdef DEBUG_MEMGUARD
2651 if (is_memguard_addr(item)) {
2652 if (zone->uz_dtor != NULL)
2653 zone->uz_dtor(item, zone->uz_size, udata);
2654 if (zone->uz_fini != NULL)
2655 zone->uz_fini(item, zone->uz_size);
2656 memguard_free(item);
2657 return;
2658 }
2659#endif
2660#ifdef INVARIANTS
2661 if (zone->uz_flags & UMA_ZONE_MALLOC)
2662 uma_dbg_free(zone, udata, item);
2663 else
2664 uma_dbg_free(zone, NULL, item);
2665#endif
2666 if (zone->uz_dtor != NULL)
2667 zone->uz_dtor(item, zone->uz_size, udata);
2668
2669 /*
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.
2672 */
2673 if (zone->uz_flags & UMA_ZFLAG_FULL)
2674 goto zfree_item;
2675
2676 /*
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.
2686 */
2687zfree_restart:
2688 critical_enter();
2689 cpu = curcpu;
2690 cache = &zone->uz_cpu[cpu];
2691
2692zfree_start:
2693 /*
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.
2697 */
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;
2705 bucket->ub_cnt++;
2706 cache->uc_frees++;
2707 critical_exit();
2708 return;
2709 }
2710
2711 /*
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.
2718 */
2719 critical_exit();
2720 if (zone->uz_count == 0 || bucketdisable)
2721 goto zfree_item;
2722
2723 lockfail = 0;
2724 if (ZONE_TRYLOCK(zone) == 0) {
2725 /* Record contention to size the buckets. */
2726 ZONE_LOCK(zone);
2727 lockfail = 1;
2728 }
2729 critical_enter();
2730 cpu = curcpu;
2731 cache = &zone->uz_cpu[cpu];
2732
2733 /*
2734 * Since we have locked the zone we may as well send back our stats.
2735 */
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;
2740
2741 bucket = cache->uc_freebucket;
2742 if (bucket != NULL && bucket->ub_cnt < bucket->ub_entries) {
2743 ZONE_UNLOCK(zone);
2744 goto zfree_start;
2745 }
2746 cache->uc_freebucket = NULL;
2747
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");
2752#endif
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);
2757 }
2758
2759 /* We are no longer associated with this CPU. */
2760 critical_exit();
2761
2762 /*
2763 * We bump the uz count when the cache size is insufficient to
2764 * handle the working set.
2765 */
2766 if (lockfail && zone->uz_count < BUCKET_MAX)
2767 zone->uz_count++;
2768 ZONE_UNLOCK(zone);
2769
2770#ifdef UMA_DEBUG_ALLOC
2771 printf("uma_zfree: Allocating new free bucket.\n");
2772#endif
2773 bucket = bucket_alloc(zone, udata, M_NOWAIT);
2774 if (bucket) {
2775 critical_enter();
2776 cpu = curcpu;
2777 cache = &zone->uz_cpu[cpu];
2778 if (cache->uc_freebucket == NULL) {
2779 cache->uc_freebucket = bucket;
2780 goto zfree_start;
2781 }
2782 /*
2783 * We lost the race, start over. We have to drop our
2784 * critical section to free the bucket.
2785 */
2786 critical_exit();
2787 bucket_free(zone, bucket, udata);
2788 goto zfree_restart;
2789 }
2790
2791 /*
2792 * If nothing else caught this, we'll just do an internal free.
2793 */
2794zfree_item:
2795 zone_free_item(zone, item, udata, SKIP_DTOR);
2796
2797 return;
2798}
2799
2800static void
2801slab_free_item(uma_keg_t keg, uma_slab_t slab, void *item)
2802{
2803 uint8_t freei;
2804
2805 mtx_assert(&keg->uk_lock, MA_OWNED);
2806 MPASS(keg == slab->us_keg);
2807
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);
2815 }
2816
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++;
2821
2822 /* Keg statistics. */
2823 keg->uk_free++;
2824}
2825
2826static void
2827zone_release(uma_zone_t zone, void **bucket, int cnt)
2828{
2829 void *item;
2830 uma_slab_t slab;
2831 uma_keg_t keg;
2832 uint8_t *mem;
2833 int clearfull;
2834 int i;
2835
2836 clearfull = 0;
2837 keg = zone_first_keg(zone);
2838 KEG_LOCK(keg);
2839 for (i = 0; i < cnt; i++) {
2840 item = bucket[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);
2845 } else {
2846 mem += keg->uk_pgoff;
2847 slab = (uma_slab_t)mem;
2848 }
2849 } else {
2850 slab = vtoslab((vm_offset_t)item);
2851 if (slab->us_keg != keg) {
2852 KEG_UNLOCK(keg);
2853 keg = slab->us_keg;
2854 KEG_LOCK(keg);
2855 }
2856 }
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;
2861 clearfull = 1;
2862 }
2863
2864 /*
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
2869 * threads etc).
2870 */
2871 wakeup(keg);
2872 }
2873 }
2874 KEG_UNLOCK(keg);
2875 if (clearfull) {
2876 ZONE_LOCK(zone);
2877 zone->uz_flags &= ~UMA_ZFLAG_FULL;
2878 wakeup(zone);
2879 ZONE_UNLOCK(zone);
2880 }
2881
2882}
2883
2884/*
2885 * Frees a single item to any zone.
2886 *
2887 * Arguments:
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
2892 */
2893static void
2894zone_free_item(uma_zone_t zone, void *item, void *udata, enum zfreeskip skip)
2895{
2896
2897#ifdef INVARIANTS
2898 if (skip == SKIP_NONE) {
2899 if (zone->uz_flags & UMA_ZONE_MALLOC)
2900 uma_dbg_free(zone, udata, item);
2901 else
2902 uma_dbg_free(zone, NULL, item);
2903 }
2904#endif
2905 if (skip < SKIP_DTOR && zone->uz_dtor)
2906 zone->uz_dtor(item, zone->uz_size, udata);
2907
2908 if (skip < SKIP_FINI && zone->uz_fini)
2909 zone->uz_fini(item, zone->uz_size);
2910
2911 atomic_add_long(&zone->uz_frees, 1);
2912 zone->uz_release(zone->uz_arg, &item, 1);
2913}
2914
2915/* See uma.h */
2916int
2917uma_zone_set_max(uma_zone_t zone, int nitems)
2918{
2919 uma_keg_t keg;
2920
2921 keg = zone_first_keg(zone);
2922 if (keg == NULL)
2923 return (0);
2924 KEG_LOCK(keg);
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;
2929 KEG_UNLOCK(keg);
2930
2931 return (nitems);
2932}
2933
2934/* See uma.h */
2935int
2936uma_zone_get_max(uma_zone_t zone)
2937{
2938 int nitems;
2939 uma_keg_t keg;
2940
2941 keg = zone_first_keg(zone);
2942 if (keg == NULL)
2943 return (0);
2944 KEG_LOCK(keg);
2945 nitems = keg->uk_maxpages * keg->uk_ipers;
2946 KEG_UNLOCK(keg);
2947
2948 return (nitems);
2949}
2950
2951/* See uma.h */
2952void
2953uma_zone_set_warning(uma_zone_t zone, const char *warning)
2954{
2955
2956 ZONE_LOCK(zone);
2957 zone->uz_warning = warning;
2958 ZONE_UNLOCK(zone);
2959}
2960
2961/* See uma.h */
2962void
2963uma_zone_set_maxaction(uma_zone_t zone, uma_maxaction_t maxaction)
2964{
2965
2966 ZONE_LOCK(zone);
2967 TASK_INIT(&zone->uz_maxaction, 0, (task_fn_t *)maxaction, zone);
2968 ZONE_UNLOCK(zone);
2969}
2970
2971/* See uma.h */
2972int
2973uma_zone_get_cur(uma_zone_t zone)
2974{
2975 int64_t nitems;
2976 u_int i;
2977
2978 ZONE_LOCK(zone);
2979 nitems = zone->uz_allocs - zone->uz_frees;
2980 CPU_FOREACH(i) {
2981 /*
2982 * See the comment in sysctl_vm_zone_stats() regarding the
2983 * safety of accessing the per-cpu caches. With the zone lock
2984 * held, it is safe, but can potentially result in stale data.
2985 */
2986 nitems += zone->uz_cpu[i].uc_allocs -
2987 zone->uz_cpu[i].uc_frees;
2988 }
2989 ZONE_UNLOCK(zone);
2990
2991 return (nitems < 0 ? 0 : nitems);
2992}
2993
2994/* See uma.h */
2995void
2996uma_zone_set_init(uma_zone_t zone, uma_init uminit)
2997{
2998 uma_keg_t keg;
2999
3000 keg = zone_first_keg(zone);
3001 KASSERT(keg != NULL, ("uma_zone_set_init: Invalid zone type"));
3002 KEG_LOCK(keg);
3003 KASSERT(keg->uk_pages == 0,
3004 ("uma_zone_set_init on non-empty keg"));
3005 keg->uk_init = uminit;
3006 KEG_UNLOCK(keg);
3007}
3008
3009/* See uma.h */
3010void
3011uma_zone_set_fini(uma_zone_t zone, uma_fini fini)
3012{
3013 uma_keg_t keg;
3014
3015 keg = zone_first_keg(zone);
3016 KASSERT(keg != NULL, ("uma_zone_set_fini: Invalid zone type"));
3017 KEG_LOCK(keg);
3018 KASSERT(keg->uk_pages == 0,
3019 ("uma_zone_set_fini on non-empty keg"));
3020 keg->uk_fini = fini;
3021 KEG_UNLOCK(keg);
3022}
3023
3024/* See uma.h */
3025void
3026uma_zone_set_zinit(uma_zone_t zone, uma_init zinit)
3027{
3028
3029 ZONE_LOCK(zone);
3030 KASSERT(zone_first_keg(zone)->uk_pages == 0,
3031 ("uma_zone_set_zinit on non-empty keg"));
3032 zone->uz_init = zinit;
3033 ZONE_UNLOCK(zone);
3034}
3035
3036/* See uma.h */
3037void
3038uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini)
3039{
3040
3041 ZONE_LOCK(zone);
3042 KASSERT(zone_first_keg(zone)->uk_pages == 0,
3043 ("uma_zone_set_zfini on non-empty keg"));
3044 zone->uz_fini = zfini;
3045 ZONE_UNLOCK(zone);
3046}
3047
3048/* See uma.h */
3049/* XXX uk_freef is not actually used with the zone locked */
3050void
3051uma_zone_set_freef(uma_zone_t zone, uma_free freef)
3052{
3053 uma_keg_t keg;
3054
3055 keg = zone_first_keg(zone);
3056 KASSERT(keg != NULL, ("uma_zone_set_freef: Invalid zone type"));
3057 KEG_LOCK(keg);
3058 keg->uk_freef = freef;
3059 KEG_UNLOCK(keg);
3060}
3061
3062/* See uma.h */
3063/* XXX uk_allocf is not actually used with the zone locked */
3064void
3065uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf)
3066{
3067 uma_keg_t keg;
3068
3069 keg = zone_first_keg(zone);
3070 KEG_LOCK(keg);
3071 keg->uk_allocf = allocf;
3072 KEG_UNLOCK(keg);
3073}
3074
3075/* See uma.h */
3076void
3077uma_zone_reserve(uma_zone_t zone, int items)
3078{
3079 uma_keg_t keg;
3080
3081 keg = zone_first_keg(zone);
3082 if (keg == NULL)
3083 return;
3084 KEG_LOCK(keg);
3085 keg->uk_reserve = items;
3086 KEG_UNLOCK(keg);
3087
3088 return;
3089}
3090
3091/* See uma.h */
3092int
3093uma_zone_reserve_kva(uma_zone_t zone, int count)
3094{
3095 uma_keg_t keg;
3096 vm_offset_t kva;
3097 u_int pages;
3098
3099 keg = zone_first_keg(zone);
3100 if (keg == NULL)
3101 return (0);
3102 pages = count / keg->uk_ipers;
3103
3104 if (pages * keg->uk_ipers < count)
3105 pages++;
3106
3107#ifdef UMA_MD_SMALL_ALLOC
3108 if (keg->uk_ppera > 1) {
3109#else
3110 if (1) {
3111#endif
3112 kva = kva_alloc((vm_size_t)pages * UMA_SLAB_SIZE);
3113 if (kva == 0)
3114 return (0);
3115 } else
3116 kva = 0;
3117 KEG_LOCK(keg);
3118 keg->uk_kva = kva;
3119 keg->uk_offset = 0;
3120 keg->uk_maxpages = pages;
3121#ifdef UMA_MD_SMALL_ALLOC
3122 keg->uk_allocf = (keg->uk_ppera > 1) ? noobj_alloc : uma_small_alloc;
3123#else
3124 keg->uk_allocf = noobj_alloc;
3125#endif
3126 keg->uk_flags |= UMA_ZONE_NOFREE;
3127 KEG_UNLOCK(keg);
3128
3129 return (1);
3130}
3131
3132/* See uma.h */
3133void
3134uma_prealloc(uma_zone_t zone, int items)
3135{
3136 int slabs;
3137 uma_slab_t slab;
3138 uma_keg_t keg;
3139
3140 keg = zone_first_keg(zone);
3141 if (keg == NULL)
3142 return;
3143 KEG_LOCK(keg);
3144 slabs = items / keg->uk_ipers;
3145 if (slabs * keg->uk_ipers < items)
3146 slabs++;
3147 while (slabs > 0) {
3148 slab = keg_alloc_slab(keg, zone, M_WAITOK);
3149 if (slab == NULL)
3150 break;
3151 MPASS(slab->us_keg == keg);
3152 LIST_INSERT_HEAD(&keg->uk_free_slab, slab, us_link);
3153 slabs--;
3154 }
3155 KEG_UNLOCK(keg);
3156}
3157
3158/* See uma.h */
3159static void
3160uma_reclaim_locked(bool kmem_danger)
3161{
3162
3163#ifdef UMA_DEBUG
3164 printf("UMA: vm asked us to release pages!\n");
3165#endif
3166 sx_assert(&uma_drain_lock, SA_XLOCKED);
3167 bucket_enable();
3168 zone_foreach(zone_drain);
3169 if (vm_page_count_min() || kmem_danger) {
3170 cache_drain_safe(NULL);
3171 zone_foreach(zone_drain);
3172 }
3173 /*
3174 * Some slabs may have been freed but this zone will be visited early
3175 * we visit again so that we can free pages that are empty once other
3176 * zones are drained. We have to do the same for buckets.
3177 */
3178 zone_drain(slabzone);
3179 bucket_zone_drain();
3180}
3181
3182void
3183uma_reclaim(void)
3184{
3185
3186 sx_xlock(&uma_drain_lock);
3187 uma_reclaim_locked(false);
3188 sx_xunlock(&uma_drain_lock);
3189}
3190
3191static int uma_reclaim_needed;
3192
3193void
3194uma_reclaim_wakeup(void)
3195{
3196
3197 uma_reclaim_needed = 1;
3198 wakeup(&uma_reclaim_needed);
3199}
3200
3201void
3202uma_reclaim_worker(void *arg __unused)
3203{
3204
3205 sx_xlock(&uma_drain_lock);
3206 for (;;) {
3207 sx_sleep(&uma_reclaim_needed, &uma_drain_lock, PVM,
3208 "umarcl", 0);
3209 if (uma_reclaim_needed) {
3210 uma_reclaim_needed = 0;
3211 uma_reclaim_locked(true);
3212 }
3213 }
3214}
3215
3216/* See uma.h */
3217int
3218uma_zone_exhausted(uma_zone_t zone)
3219{
3220 int full;
3221
3222 ZONE_LOCK(zone);
3223 full = (zone->uz_flags & UMA_ZFLAG_FULL);
3224 ZONE_UNLOCK(zone);
3225 return (full);
3226}
3227
3228int
3229uma_zone_exhausted_nolock(uma_zone_t zone)
3230{
3231 return (zone->uz_flags & UMA_ZFLAG_FULL);
3232}
3233
3234void *
3235uma_large_malloc(vm_size_t size, int wait)
3236{
3237 void *mem;
3238 uma_slab_t slab;
3239 uint8_t flags;
3240
3241 slab = zone_alloc_item(slabzone, NULL, wait);
3242 if (slab == NULL)
3243 return (NULL);
3244 mem = page_alloc(NULL, size, &flags, wait);
3245 if (mem) {
3246 vsetslab((vm_offset_t)mem, slab);
3247 slab->us_data = mem;
3248 slab->us_flags = flags | UMA_SLAB_MALLOC;
3249 slab->us_size = size;
3250 } else {
3251 zone_free_item(slabzone, slab, NULL, SKIP_NONE);
3252 }
3253
3254 return (mem);
3255}
3256
3257void
3258uma_large_free(uma_slab_t slab)
3259{
3260
3261 page_free(slab->us_data, slab->us_size, slab->us_flags);
3262 zone_free_item(slabzone, slab, NULL, SKIP_NONE);
3263}
3264
3265static void
3266uma_zero_item(void *item, uma_zone_t zone)
3267{
3268 int i;
3269
3270 if (zone->uz_flags & UMA_ZONE_PCPU) {
3271 CPU_FOREACH(i)
3272 bzero(zpcpu_get_cpu(item, i), zone->uz_size);
3273 } else
3274 bzero(item, zone->uz_size);
3275}
3276
3277void
3278uma_print_stats(void)
3279{
3280 zone_foreach(uma_print_zone);
3281}
3282
3283static void
3284slab_print(uma_slab_t slab)
3285{
3286 printf("slab: keg %p, data %p, freecount %d\n",
3287 slab->us_keg, slab->us_data, slab->us_freecount);
3288}
3289
3290static void
3291cache_print(uma_cache_t cache)
3292{
3293 printf("alloc: %p(%d), free: %p(%d)\n",
3294 cache->uc_allocbucket,
3295 cache->uc_allocbucket?cache->uc_allocbucket->ub_cnt:0,
3296 cache->uc_freebucket,
3297 cache->uc_freebucket?cache->uc_freebucket->ub_cnt:0);
3298}
3299
3300static void
3301uma_print_keg(uma_keg_t keg)
3302{
3303 uma_slab_t slab;
3304
3305 printf("keg: %s(%p) size %d(%d) flags %#x ipers %d ppera %d "
3306 "out %d free %d limit %d\n",
3307 keg->uk_name, keg, keg->uk_size, keg->uk_rsize, keg->uk_flags,
3308 keg->uk_ipers, keg->uk_ppera,
3309 (keg->uk_ipers * keg->uk_pages) - keg->uk_free, keg->uk_free,
3310 (keg->uk_maxpages / keg->uk_ppera) * keg->uk_ipers);
3311 printf("Part slabs:\n");
3312 LIST_FOREACH(slab, &keg->uk_part_slab, us_link)
3313 slab_print(slab);
3314 printf("Free slabs:\n");
3315 LIST_FOREACH(slab, &keg->uk_free_slab, us_link)
3316 slab_print(slab);
3317 printf("Full slabs:\n");
3318 LIST_FOREACH(slab, &keg->uk_full_slab, us_link)
3319 slab_print(slab);
3320}
3321
3322void
3323uma_print_zone(uma_zone_t zone)
3324{
3325 uma_cache_t cache;
3326 uma_klink_t kl;
3327 int i;
3328
3329 printf("zone: %s(%p) size %d flags %#x\n",
3330 zone->uz_name, zone, zone->uz_size, zone->uz_flags);
3331 LIST_FOREACH(kl, &zone->uz_kegs, kl_link)
3332 uma_print_keg(kl->kl_keg);
3333 CPU_FOREACH(i) {
3334 cache = &zone->uz_cpu[i];
3335 printf("CPU %d Cache:\n", i);
3336 cache_print(cache);
3337 }
3338}
3339
3340#ifdef DDB
3341/*
3342 * Generate statistics across both the zone and its per-cpu cache's. Return
3343 * desired statistics if the pointer is non-NULL for that statistic.
3344 *
3345 * Note: does not update the zone statistics, as it can't safely clear the
3346 * per-CPU cache statistic.
3347 *
3348 * XXXRW: Following the uc_allocbucket and uc_freebucket pointers here isn't
3349 * safe from off-CPU; we should modify the caches to track this information
3350 * directly so that we don't have to.
3351 */
3352static void
3353uma_zone_sumstat(uma_zone_t z, int *cachefreep, uint64_t *allocsp,
3354 uint64_t *freesp, uint64_t *sleepsp)
3355{
3356 uma_cache_t cache;
3357 uint64_t allocs, frees, sleeps;
3358 int cachefree, cpu;
3359
3360 allocs = frees = sleeps = 0;
3361 cachefree = 0;
3362 CPU_FOREACH(cpu) {
3363 cache = &z->uz_cpu[cpu];
3364 if (cache->uc_allocbucket != NULL)
3365 cachefree += cache->uc_allocbucket->ub_cnt;
3366 if (cache->uc_freebucket != NULL)
3367 cachefree += cache->uc_freebucket->ub_cnt;
3368 allocs += cache->uc_allocs;
3369 frees += cache->uc_frees;
3370 }
3371 allocs += z->uz_allocs;
3372 frees += z->uz_frees;
3373 sleeps += z->uz_sleeps;
3374 if (cachefreep != NULL)
3375 *cachefreep = cachefree;
3376 if (allocsp != NULL)
3377 *allocsp = allocs;
3378 if (freesp != NULL)
3379 *freesp = frees;
3380 if (sleepsp != NULL)
3381 *sleepsp = sleeps;
3382}
3383#endif /* DDB */
3384
3385static int
3386sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS)
3387{
3388 uma_keg_t kz;
3389 uma_zone_t z;
3390 int count;
3391
3392 count = 0;
3393 rw_rlock(&uma_rwlock);
3394 LIST_FOREACH(kz, &uma_kegs, uk_link) {
3395 LIST_FOREACH(z, &kz->uk_zones, uz_link)
3396 count++;
3397 }
3398 rw_runlock(&uma_rwlock);
3399 return (sysctl_handle_int(oidp, &count, 0, req));
3400}
3401
3402static int
3403sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS)
3404{
3405 struct uma_stream_header ush;
3406 struct uma_type_header uth;
3407 struct uma_percpu_stat ups;
3408 uma_bucket_t bucket;
3409 struct sbuf sbuf;
3410 uma_cache_t cache;
3411 uma_klink_t kl;
3412 uma_keg_t kz;
3413 uma_zone_t z;
3414 uma_keg_t k;
3415 int count, error, i;
3416
3417 error = sysctl_wire_old_buffer(req, 0);
3418 if (error != 0)
3419 return (error);
3420 sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
3421 sbuf_clear_flags(&sbuf, SBUF_INCLUDENUL);
3422
3423 count = 0;
3424 rw_rlock(&uma_rwlock);
3425 LIST_FOREACH(kz, &uma_kegs, uk_link) {
3426 LIST_FOREACH(z, &kz->uk_zones, uz_link)
3427 count++;
3428 }
3429
3430 /*
3431 * Insert stream header.
3432 */
3433 bzero(&ush, sizeof(ush));
3434 ush.ush_version = UMA_STREAM_VERSION;
3435 ush.ush_maxcpus = (mp_maxid + 1);
3436 ush.ush_count = count;
3437 (void)sbuf_bcat(&sbuf, &ush, sizeof(ush));
3438
3439 LIST_FOREACH(kz, &uma_kegs, uk_link) {
3440 LIST_FOREACH(z, &kz->uk_zones, uz_link) {
3441 bzero(&uth, sizeof(uth));
3442 ZONE_LOCK(z);
3443 strlcpy(uth.uth_name, z->uz_name, UTH_MAX_NAME);
3444 uth.uth_align = kz->uk_align;
3445 uth.uth_size = kz->uk_size;
3446 uth.uth_rsize = kz->uk_rsize;
3447 LIST_FOREACH(kl, &z->uz_kegs, kl_link) {
3448 k = kl->kl_keg;
3449 uth.uth_maxpages += k->uk_maxpages;
3450 uth.uth_pages += k->uk_pages;
3451 uth.uth_keg_free += k->uk_free;
3452 uth.uth_limit = (k->uk_maxpages / k->uk_ppera)
3453 * k->uk_ipers;
3454 }
3455
3456 /*
3457 * A zone is secondary is it is not the first entry
3458 * on the keg's zone list.
3459 */
3460 if ((z->uz_flags & UMA_ZONE_SECONDARY) &&
3461 (LIST_FIRST(&kz->uk_zones) != z))
3462 uth.uth_zone_flags = UTH_ZONE_SECONDARY;
3463
3464 LIST_FOREACH(bucket, &z->uz_buckets, ub_link)
3465 uth.uth_zone_free += bucket->ub_cnt;
3466 uth.uth_allocs = z->uz_allocs;
3467 uth.uth_frees = z->uz_frees;
3468 uth.uth_fails = z->uz_fails;
3469 uth.uth_sleeps = z->uz_sleeps;
3470 (void)sbuf_bcat(&sbuf, &uth, sizeof(uth));
3471 /*
3472 * While it is not normally safe to access the cache
3473 * bucket pointers while not on the CPU that owns the
3474 * cache, we only allow the pointers to be exchanged
3475 * without the zone lock held, not invalidated, so
3476 * accept the possible race associated with bucket
3477 * exchange during monitoring.
3478 */
3479 for (i = 0; i < (mp_maxid + 1); i++) {
3480 bzero(&ups, sizeof(ups));
3481 if (kz->uk_flags & UMA_ZFLAG_INTERNAL)
3482 goto skip;
3483 if (CPU_ABSENT(i))
3484 goto skip;
3485 cache = &z->uz_cpu[i];
3486 if (cache->uc_allocbucket != NULL)
3487 ups.ups_cache_free +=
3488 cache->uc_allocbucket->ub_cnt;
3489 if (cache->uc_freebucket != NULL)
3490 ups.ups_cache_free +=
3491 cache->uc_freebucket->ub_cnt;
3492 ups.ups_allocs = cache->uc_allocs;
3493 ups.ups_frees = cache->uc_frees;
3494skip:
3495 (void)sbuf_bcat(&sbuf, &ups, sizeof(ups));
3496 }
3497 ZONE_UNLOCK(z);
3498 }
3499 }
3500 rw_runlock(&uma_rwlock);
3501 error = sbuf_finish(&sbuf);
3502 sbuf_delete(&sbuf);
3503 return (error);
3504}
3505
3506int
3507sysctl_handle_uma_zone_max(SYSCTL_HANDLER_ARGS)
3508{
3509 uma_zone_t zone = *(uma_zone_t *)arg1;
3510 int error, max;
3511
3512 max = uma_zone_get_max(zone);
3513 error = sysctl_handle_int(oidp, &max, 0, req);
3514 if (error || !req->newptr)
3515 return (error);
3516
3517 uma_zone_set_max(zone, max);
3518
3519 return (0);
3520}
3521
3522int
3523sysctl_handle_uma_zone_cur(SYSCTL_HANDLER_ARGS)
3524{
3525 uma_zone_t zone = *(uma_zone_t *)arg1;
3526 int cur;
3527
3528 cur = uma_zone_get_cur(zone);
3529 return (sysctl_handle_int(oidp, &cur, 0, req));
3530}
3531
3532#ifdef INVARIANTS
3533static uma_slab_t
3534uma_dbg_getslab(uma_zone_t zone, void *item)
3535{
3536 uma_slab_t slab;
3537 uma_keg_t keg;
3538 uint8_t *mem;
3539
3540 mem = (uint8_t *)((uintptr_t)item & (~UMA_SLAB_MASK));
3541 if (zone->uz_flags & UMA_ZONE_VTOSLAB) {
3542 slab = vtoslab((vm_offset_t)mem);
3543 } else {
3544 /*
3545 * It is safe to return the slab here even though the
3546 * zone is unlocked because the item's allocation state
3547 * essentially holds a reference.
3548 */
3549 ZONE_LOCK(zone);
3550 keg = LIST_FIRST(&zone->uz_kegs)->kl_keg;
3551 if (keg->uk_flags & UMA_ZONE_HASH)
3552 slab = hash_sfind(&keg->uk_hash, mem);
3553 else
3554 slab = (uma_slab_t)(mem + keg->uk_pgoff);
3555 ZONE_UNLOCK(zone);
3556 }
3557
3558 return (slab);
3559}
3560
3561/*
3562 * Set up the slab's freei data such that uma_dbg_free can function.
3563 *
3564 */
3565static void
3566uma_dbg_alloc(uma_zone_t zone, uma_slab_t slab, void *item)
3567{
3568 uma_keg_t keg;
3569 int freei;
3570
3571 if (zone_first_keg(zone) == NULL)
3572 return;
3573 if (slab == NULL) {
3574 slab = uma_dbg_getslab(zone, item);
3575 if (slab == NULL)
3576 panic("uma: item %p did not belong to zone %s\n",
3577 item, zone->uz_name);
3578 }
3579 keg = slab->us_keg;
3580 freei = ((uintptr_t)item - (uintptr_t)slab->us_data) / keg->uk_rsize;
3581
3582 if (BIT_ISSET(SLAB_SETSIZE, freei, &slab->us_debugfree))
3583 panic("Duplicate alloc of %p from zone %p(%s) slab %p(%d)\n",
3584 item, zone, zone->uz_name, slab, freei);
3585 BIT_SET_ATOMIC(SLAB_SETSIZE, freei, &slab->us_debugfree);
3586
3587 return;
3588}
3589
3590/*
3591 * Verifies freed addresses. Checks for alignment, valid slab membership
3592 * and duplicate frees.
3593 *
3594 */
3595static void
3596uma_dbg_free(uma_zone_t zone, uma_slab_t slab, void *item)
3597{
3598 uma_keg_t keg;
3599 int freei;
3600
3601 if (zone_first_keg(zone) == NULL)
3602 return;
3603 if (slab == NULL) {
3604 slab = uma_dbg_getslab(zone, item);
3605 if (slab == NULL)
3606 panic("uma: Freed item %p did not belong to zone %s\n",
3607 item, zone->uz_name);
3608 }
3609 keg = slab->us_keg;
3610 freei = ((uintptr_t)item - (uintptr_t)slab->us_data) / keg->uk_rsize;
3611
3612 if (freei >= keg->uk_ipers)
3613 panic("Invalid free of %p from zone %p(%s) slab %p(%d)\n",
3614 item, zone, zone->uz_name, slab, freei);
3615
3616 if (((freei * keg->uk_rsize) + slab->us_data) != item)
3617 panic("Unaligned free of %p from zone %p(%s) slab %p(%d)\n",
3618 item, zone, zone->uz_name, slab, freei);
3619
3620 if (!BIT_ISSET(SLAB_SETSIZE, freei, &slab->us_debugfree))
3621 panic("Duplicate free of %p from zone %p(%s) slab %p(%d)\n",
3622 item, zone, zone->uz_name, slab, freei);
3623
3624 BIT_CLR_ATOMIC(SLAB_SETSIZE, freei, &slab->us_debugfree);
3625}
3626#endif /* INVARIANTS */
3627
3628#ifdef DDB
3629DB_SHOW_COMMAND(uma, db_show_uma)
3630{
3631 uint64_t allocs, frees, sleeps;
3632 uma_bucket_t bucket;
3633 uma_keg_t kz;
3634 uma_zone_t z;
3635 int cachefree;
3636
3637 db_printf("%18s %8s %8s %8s %12s %8s %8s\n", "Zone", "Size", "Used",
3638 "Free", "Requests", "Sleeps", "Bucket");
3639 LIST_FOREACH(kz, &uma_kegs, uk_link) {
3640 LIST_FOREACH(z, &kz->uk_zones, uz_link) {
3641 if (kz->uk_flags & UMA_ZFLAG_INTERNAL) {
3642 allocs = z->uz_allocs;
3643 frees = z->uz_frees;
3644 sleeps = z->uz_sleeps;
3645 cachefree = 0;
3646 } else
3647 uma_zone_sumstat(z, &cachefree, &allocs,
3648 &frees, &sleeps);
3649 if (!((z->uz_flags & UMA_ZONE_SECONDARY) &&
3650 (LIST_FIRST(&kz->uk_zones) != z)))
3651 cachefree += kz->uk_free;
3652 LIST_FOREACH(bucket, &z->uz_buckets, ub_link)
3653 cachefree += bucket->ub_cnt;
3654 db_printf("%18s %8ju %8jd %8d %12ju %8ju %8u\n",
3655 z->uz_name, (uintmax_t)kz->uk_size,
3656 (intmax_t)(allocs - frees), cachefree,
3657 (uintmax_t)allocs, sleeps, z->uz_count);
3658 if (db_pager_quit)
3659 return;
3660 }
3661 }
3662}
3663
3664DB_SHOW_COMMAND(umacache, db_show_umacache)
3665{
3666 uint64_t allocs, frees;
3667 uma_bucket_t bucket;
3668 uma_zone_t z;
3669 int cachefree;
3670
3671 db_printf("%18s %8s %8s %8s %12s %8s\n", "Zone", "Size", "Used", "Free",
3672 "Requests", "Bucket");
3673 LIST_FOREACH(z, &uma_cachezones, uz_link) {
3674 uma_zone_sumstat(z, &cachefree, &allocs, &frees, NULL);
3675 LIST_FOREACH(bucket, &z->uz_buckets, ub_link)
3676 cachefree += bucket->ub_cnt;
3677 db_printf("%18s %8ju %8jd %8d %12ju %8u\n",
3678 z->uz_name, (uintmax_t)z->uz_size,
3679 (intmax_t)(allocs - frees), cachefree,
3680 (uintmax_t)allocs, z->uz_count);
3681 if (db_pager_quit)
3682 return;
3683 }
3684}
3685#endif /* DDB */