4 * KERN_SLABALLOC.C - Kernel SLAB memory allocator
6 * Copyright (c) 2003,2004,2010 The DragonFly Project. All rights reserved.
8 * This code is derived from software contributed to The DragonFly Project
9 * by Matthew Dillon <dillon@backplane.com>
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in
19 * the documentation and/or other materials provided with the
21 * 3. Neither the name of The DragonFly Project nor the names of its
22 * contributors may be used to endorse or promote products derived
23 * from this software without specific, prior written permission.
25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
26 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
27 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
28 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
29 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
30 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
31 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
32 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
33 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
34 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
35 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 * This module implements a slab allocator drop-in replacement for the
41 * A slab allocator reserves a ZONE for each chunk size, then lays the
42 * chunks out in an array within the zone. Allocation and deallocation
43 * is nearly instantanious, and fragmentation/overhead losses are limited
44 * to a fixed worst-case amount.
46 * The downside of this slab implementation is in the chunk size
47 * multiplied by the number of zones. ~80 zones * 128K = 10MB of VM per cpu.
48 * In a kernel implementation all this memory will be physical so
49 * the zone size is adjusted downward on machines with less physical
50 * memory. The upside is that overhead is bounded... this is the *worst*
53 * Slab management is done on a per-cpu basis and no locking or mutexes
54 * are required, only a critical section. When one cpu frees memory
55 * belonging to another cpu's slab manager an asynchronous IPI message
56 * will be queued to execute the operation. In addition, both the
57 * high level slab allocator and the low level zone allocator optimize
58 * M_ZERO requests, and the slab allocator does not have to pre initialize
59 * the linked list of chunks.
61 * XXX Balancing is needed between cpus. Balance will be handled through
62 * asynchronous IPIs primarily by reassigning the z_Cpu ownership of chunks.
64 * XXX If we have to allocate a new zone and M_USE_RESERVE is set, use of
65 * the new zone should be restricted to M_USE_RESERVE requests only.
67 * Alloc Size Chunking Number of zones
77 * (if PAGE_SIZE is 4K the maximum zone allocation is 16383)
79 * Allocations >= ZoneLimit go directly to kmem.
81 * Alignment properties:
82 * - All power-of-2 sized allocations are power-of-2 aligned.
83 * - Allocations with M_POWEROF2 are power-of-2 aligned on the nearest
84 * power-of-2 round up of 'size'.
85 * - Non-power-of-2 sized allocations are zone chunk size aligned (see the
86 * above table 'Chunking' column).
88 * API REQUIREMENTS AND SIDE EFFECTS
90 * To operate as a drop-in replacement to the FreeBSD-4.x malloc() we
91 * have remained compatible with the following API requirements:
93 * + malloc(0) is allowed and returns non-NULL (ahc driver)
94 * + ability to allocate arbitrarily large chunks of memory
99 #include <sys/param.h>
100 #include <sys/systm.h>
101 #include <sys/kernel.h>
102 #include <sys/slaballoc.h>
103 #include <sys/mbuf.h>
104 #include <sys/vmmeter.h>
105 #include <sys/lock.h>
106 #include <sys/thread.h>
107 #include <sys/globaldata.h>
108 #include <sys/sysctl.h>
112 #include <vm/vm_param.h>
113 #include <vm/vm_kern.h>
114 #include <vm/vm_extern.h>
115 #include <vm/vm_object.h>
117 #include <vm/vm_map.h>
118 #include <vm/vm_page.h>
119 #include <vm/vm_pageout.h>
121 #include <machine/cpu.h>
123 #include <sys/thread2.h>
124 #include <vm/vm_page2.h>
126 #define btokup(z) (&pmap_kvtom((vm_offset_t)(z))->ku_pagecnt)
128 #define MEMORY_STRING "ptr=%p type=%p size=%lu flags=%04x"
129 #define MEMORY_ARGS void *ptr, void *type, unsigned long size, int flags
131 #if !defined(KTR_MEMORY)
132 #define KTR_MEMORY KTR_ALL
134 KTR_INFO_MASTER(memory);
135 KTR_INFO(KTR_MEMORY, memory, malloc_beg, 0, "malloc begin");
136 KTR_INFO(KTR_MEMORY, memory, malloc_end, 1, MEMORY_STRING, MEMORY_ARGS);
137 KTR_INFO(KTR_MEMORY, memory, free_zero, 2, MEMORY_STRING, MEMORY_ARGS);
138 KTR_INFO(KTR_MEMORY, memory, free_ovsz, 3, MEMORY_STRING, MEMORY_ARGS);
139 KTR_INFO(KTR_MEMORY, memory, free_ovsz_delayed, 4, MEMORY_STRING, MEMORY_ARGS);
140 KTR_INFO(KTR_MEMORY, memory, free_chunk, 5, MEMORY_STRING, MEMORY_ARGS);
141 KTR_INFO(KTR_MEMORY, memory, free_request, 6, MEMORY_STRING, MEMORY_ARGS);
142 KTR_INFO(KTR_MEMORY, memory, free_rem_beg, 7, MEMORY_STRING, MEMORY_ARGS);
143 KTR_INFO(KTR_MEMORY, memory, free_rem_end, 8, MEMORY_STRING, MEMORY_ARGS);
144 KTR_INFO(KTR_MEMORY, memory, free_beg, 9, "free begin");
145 KTR_INFO(KTR_MEMORY, memory, free_end, 10, "free end");
147 #define logmemory(name, ptr, type, size, flags) \
148 KTR_LOG(memory_ ## name, ptr, type, size, flags)
149 #define logmemory_quick(name) \
150 KTR_LOG(memory_ ## name)
153 * Fixed globals (not per-cpu)
156 static int ZoneLimit;
157 static int ZonePageCount;
158 static uintptr_t ZoneMask;
159 static int ZoneBigAlloc; /* in KB */
160 static int ZoneGenAlloc; /* in KB */
161 struct malloc_type *kmemstatistics; /* exported to vmstat */
162 static int32_t weirdary[16];
164 static void *kmem_slab_alloc(vm_size_t bytes, vm_offset_t align, int flags);
165 static void kmem_slab_free(void *ptr, vm_size_t bytes);
167 #if defined(INVARIANTS)
168 static void chunk_mark_allocated(SLZone *z, void *chunk);
169 static void chunk_mark_free(SLZone *z, void *chunk);
171 #define chunk_mark_allocated(z, chunk)
172 #define chunk_mark_free(z, chunk)
176 * Misc constants. Note that allocations that are exact multiples of
177 * PAGE_SIZE, or exceed the zone limit, fall through to the kmem module.
179 #define ZONE_RELS_THRESH 32 /* threshold number of zones */
182 * The WEIRD_ADDR is used as known text to copy into free objects to
183 * try to create deterministic failure cases if the data is accessed after
186 #define WEIRD_ADDR 0xdeadc0de
187 #define MAX_COPY sizeof(weirdary)
188 #define ZERO_LENGTH_PTR ((void *)-8)
191 * Misc global malloc buckets
194 MALLOC_DEFINE(M_CACHE, "cache", "Various Dynamically allocated caches");
195 MALLOC_DEFINE(M_DEVBUF, "devbuf", "device driver memory");
196 MALLOC_DEFINE(M_TEMP, "temp", "misc temporary data buffers");
197 MALLOC_DEFINE(M_DRM, "m_drm", "DRM memory allocations");
199 MALLOC_DEFINE(M_IP6OPT, "ip6opt", "IPv6 options");
200 MALLOC_DEFINE(M_IP6NDP, "ip6ndp", "IPv6 Neighbor Discovery");
203 * Initialize the slab memory allocator. We have to choose a zone size based
204 * on available physical memory. We choose a zone side which is approximately
205 * 1/1024th of our memory, so if we have 128MB of ram we have a zone size of
206 * 128K. The zone size is limited to the bounds set in slaballoc.h
207 * (typically 32K min, 128K max).
209 static void kmeminit(void *dummy);
213 SYSINIT(kmem, SI_BOOT1_ALLOCATOR, SI_ORDER_FIRST, kmeminit, NULL);
217 * If enabled any memory allocated without M_ZERO is initialized to -1.
219 static int use_malloc_pattern;
220 SYSCTL_INT(_debug, OID_AUTO, use_malloc_pattern, CTLFLAG_RW,
221 &use_malloc_pattern, 0,
222 "Initialize memory to -1 if M_ZERO not specified");
225 static int ZoneRelsThresh = ZONE_RELS_THRESH;
226 SYSCTL_INT(_kern, OID_AUTO, zone_big_alloc, CTLFLAG_RD, &ZoneBigAlloc, 0, "");
227 SYSCTL_INT(_kern, OID_AUTO, zone_gen_alloc, CTLFLAG_RD, &ZoneGenAlloc, 0, "");
228 SYSCTL_INT(_kern, OID_AUTO, zone_cache, CTLFLAG_RW, &ZoneRelsThresh, 0, "");
229 static long SlabsAllocated;
230 static long SlabsFreed;
231 SYSCTL_LONG(_kern, OID_AUTO, slabs_allocated, CTLFLAG_RD,
232 &SlabsAllocated, 0, "");
233 SYSCTL_LONG(_kern, OID_AUTO, slabs_freed, CTLFLAG_RD,
235 static int SlabFreeToTail;
236 SYSCTL_INT(_kern, OID_AUTO, slab_freetotail, CTLFLAG_RW,
237 &SlabFreeToTail, 0, "");
239 static struct spinlock kmemstat_spin =
240 SPINLOCK_INITIALIZER(&kmemstat_spin, "malinit");
243 * Returns the kernel memory size limit for the purposes of initializing
244 * various subsystem caches. The smaller of available memory and the KVM
245 * memory space is returned.
247 * The size in megabytes is returned.
254 limsize = (size_t)vmstats.v_page_count * PAGE_SIZE;
255 if (limsize > KvaSize)
257 return (limsize / (1024 * 1024));
261 kmeminit(void *dummy)
267 limsize = kmem_lim_size();
268 usesize = (int)(limsize * 1024); /* convert to KB */
271 * If the machine has a large KVM space and more than 8G of ram,
272 * double the zone release threshold to reduce SMP invalidations.
273 * If more than 16G of ram, do it again.
275 * The BIOS eats a little ram so add some slop. We want 8G worth of
276 * memory sticks to trigger the first adjustment.
278 if (ZoneRelsThresh == ZONE_RELS_THRESH) {
279 if (limsize >= 7 * 1024)
281 if (limsize >= 15 * 1024)
286 * Calculate the zone size. This typically calculates to
287 * ZALLOC_MAX_ZONE_SIZE
289 ZoneSize = ZALLOC_MIN_ZONE_SIZE;
290 while (ZoneSize < ZALLOC_MAX_ZONE_SIZE && (ZoneSize << 1) < usesize)
292 ZoneLimit = ZoneSize / 4;
293 if (ZoneLimit > ZALLOC_ZONE_LIMIT)
294 ZoneLimit = ZALLOC_ZONE_LIMIT;
295 ZoneMask = ~(uintptr_t)(ZoneSize - 1);
296 ZonePageCount = ZoneSize / PAGE_SIZE;
298 for (i = 0; i < NELEM(weirdary); ++i)
299 weirdary[i] = WEIRD_ADDR;
301 ZeroPage = kmem_slab_alloc(PAGE_SIZE, PAGE_SIZE, M_WAITOK|M_ZERO);
304 kprintf("Slab ZoneSize set to %dKB\n", ZoneSize / 1024);
308 * (low level) Initialize slab-related elements in the globaldata structure.
310 * Occurs after kmeminit().
313 slab_gdinit(globaldata_t gd)
319 for (i = 0; i < NZONES; ++i)
320 TAILQ_INIT(&slgd->ZoneAry[i]);
321 TAILQ_INIT(&slgd->FreeZones);
322 TAILQ_INIT(&slgd->FreeOvZones);
326 * Initialize a malloc type tracking structure.
329 malloc_init(void *data)
331 struct malloc_type *type = data;
334 if (type->ks_magic != M_MAGIC)
335 panic("malloc type lacks magic");
337 if (type->ks_limit != 0)
340 if (vmstats.v_page_count == 0)
341 panic("malloc_init not allowed before vm init");
343 limsize = kmem_lim_size() * (1024 * 1024);
344 type->ks_limit = limsize / 10;
346 spin_lock(&kmemstat_spin);
347 type->ks_next = kmemstatistics;
348 kmemstatistics = type;
349 spin_unlock(&kmemstat_spin);
353 malloc_uninit(void *data)
355 struct malloc_type *type = data;
356 struct malloc_type *t;
362 if (type->ks_magic != M_MAGIC)
363 panic("malloc type lacks magic");
365 if (vmstats.v_page_count == 0)
366 panic("malloc_uninit not allowed before vm init");
368 if (type->ks_limit == 0)
369 panic("malloc_uninit on uninitialized type");
371 /* Make sure that all pending kfree()s are finished. */
372 lwkt_synchronize_ipiqs("muninit");
376 * memuse is only correct in aggregation. Due to memory being allocated
377 * on one cpu and freed on another individual array entries may be
378 * negative or positive (canceling each other out).
380 for (i = ttl = 0; i < ncpus; ++i)
381 ttl += type->ks_use[i].memuse;
383 kprintf("malloc_uninit: %ld bytes of '%s' still allocated on cpu %d\n",
384 ttl, type->ks_shortdesc, i);
387 spin_lock(&kmemstat_spin);
388 if (type == kmemstatistics) {
389 kmemstatistics = type->ks_next;
391 for (t = kmemstatistics; t->ks_next != NULL; t = t->ks_next) {
392 if (t->ks_next == type) {
393 t->ks_next = type->ks_next;
398 type->ks_next = NULL;
400 spin_unlock(&kmemstat_spin);
404 * Increase the kmalloc pool limit for the specified pool. No changes
405 * are the made if the pool would shrink.
408 kmalloc_raise_limit(struct malloc_type *type, size_t bytes)
410 if (type->ks_limit == 0)
414 if (type->ks_limit < bytes)
415 type->ks_limit = bytes;
419 kmalloc_set_unlimited(struct malloc_type *type)
421 type->ks_limit = kmem_lim_size() * (1024 * 1024);
425 * Dynamically create a malloc pool. This function is a NOP if *typep is
429 kmalloc_create(struct malloc_type **typep, const char *descr)
431 struct malloc_type *type;
433 if (*typep == NULL) {
434 type = kmalloc(sizeof(*type), M_TEMP, M_WAITOK | M_ZERO);
435 type->ks_magic = M_MAGIC;
436 type->ks_shortdesc = descr;
443 * Destroy a dynamically created malloc pool. This function is a NOP if
444 * the pool has already been destroyed.
447 kmalloc_destroy(struct malloc_type **typep)
449 if (*typep != NULL) {
450 malloc_uninit(*typep);
451 kfree(*typep, M_TEMP);
457 * Calculate the zone index for the allocation request size and set the
458 * allocation request size to that particular zone's chunk size.
461 zoneindex(unsigned long *bytes, unsigned long *align)
463 unsigned int n = (unsigned int)*bytes; /* unsigned for shift opt */
465 *bytes = n = (n + 7) & ~7;
467 return(n / 8 - 1); /* 8 byte chunks, 16 zones */
470 *bytes = n = (n + 15) & ~15;
476 *bytes = n = (n + 31) & ~31;
481 *bytes = n = (n + 63) & ~63;
486 *bytes = n = (n + 127) & ~127;
488 return(n / 128 + 31);
491 *bytes = n = (n + 255) & ~255;
493 return(n / 256 + 39);
495 *bytes = n = (n + 511) & ~511;
497 return(n / 512 + 47);
499 #if ZALLOC_ZONE_LIMIT > 8192
501 *bytes = n = (n + 1023) & ~1023;
503 return(n / 1024 + 55);
506 #if ZALLOC_ZONE_LIMIT > 16384
508 *bytes = n = (n + 2047) & ~2047;
510 return(n / 2048 + 63);
513 panic("Unexpected byte count %d", n);
519 clean_zone_rchunks(SLZone *z)
523 while ((bchunk = z->z_RChunks) != NULL) {
525 if (atomic_cmpset_ptr(&z->z_RChunks, bchunk, NULL)) {
526 *z->z_LChunksp = bchunk;
528 chunk_mark_free(z, bchunk);
529 z->z_LChunksp = &bchunk->c_Next;
530 bchunk = bchunk->c_Next;
540 * If the zone becomes totally free and is not the only zone listed for a
541 * chunk size we move it to the FreeZones list. We always leave at least
542 * one zone per chunk size listed, even if it is freeable.
544 * Do not move the zone if there is an IPI in_flight (z_RCount != 0),
545 * otherwise MP races can result in our free_remote code accessing a
546 * destroyed zone. The remote end interlocks z_RCount with z_RChunks
547 * so one has to test both z_NFree and z_RCount.
549 * Since this code can be called from an IPI callback, do *NOT* try to mess
550 * with kernel_map here. Hysteresis will be performed at kmalloc() time.
554 check_zone_free(SLGlobalData *slgd, SLZone *z)
558 znext = TAILQ_NEXT(z, z_Entry);
559 if (z->z_NFree == z->z_NMax && z->z_RCount == 0 &&
560 (TAILQ_FIRST(&slgd->ZoneAry[z->z_ZoneIndex]) != z || znext)
564 TAILQ_REMOVE(&slgd->ZoneAry[z->z_ZoneIndex], z, z_Entry);
567 TAILQ_INSERT_HEAD(&slgd->FreeZones, z, z_Entry);
577 * Used to debug memory corruption issues. Record up to (typically 32)
578 * allocation sources for this zone (for a particular chunk size).
582 slab_record_source(SLZone *z, const char *file, int line)
585 int b = line & (SLAB_DEBUG_ENTRIES - 1);
589 if (z->z_Sources[i].file == file && z->z_Sources[i].line == line)
591 if (z->z_Sources[i].file == NULL)
593 i = (i + 1) & (SLAB_DEBUG_ENTRIES - 1);
595 z->z_Sources[i].file = file;
596 z->z_Sources[i].line = line;
601 static __inline unsigned long
602 powerof2_size(unsigned long size)
606 if (size == 0 || powerof2(size))
614 * kmalloc() (SLAB ALLOCATOR)
616 * Allocate memory via the slab allocator. If the request is too large,
617 * or if it page-aligned beyond a certain size, we fall back to the
618 * KMEM subsystem. A SLAB tracking descriptor must be specified, use
619 * &SlabMisc if you don't care.
621 * M_RNOWAIT - don't block.
622 * M_NULLOK - return NULL instead of blocking.
623 * M_ZERO - zero the returned memory.
624 * M_USE_RESERVE - allow greater drawdown of the free list
625 * M_USE_INTERRUPT_RESERVE - allow the freelist to be exhausted
626 * M_POWEROF2 - roundup size to the nearest power of 2
633 kmalloc_debug(unsigned long size, struct malloc_type *type, int flags,
634 const char *file, int line)
637 kmalloc(unsigned long size, struct malloc_type *type, int flags)
643 struct globaldata *gd;
650 logmemory_quick(malloc_beg);
655 * XXX silly to have this in the critical path.
657 if (type->ks_limit == 0) {
664 if (flags & M_POWEROF2)
665 size = powerof2_size(size);
668 * Handle the case where the limit is reached. Panic if we can't return
669 * NULL. The original malloc code looped, but this tended to
670 * simply deadlock the computer.
672 * ks_loosememuse is an up-only limit that is NOT MP-synchronized, used
673 * to determine if a more complete limit check should be done. The
674 * actual memory use is tracked via ks_use[cpu].memuse.
676 while (type->ks_loosememuse >= type->ks_limit) {
680 for (i = ttl = 0; i < ncpus; ++i)
681 ttl += type->ks_use[i].memuse;
682 type->ks_loosememuse = ttl; /* not MP synchronized */
683 if ((ssize_t)ttl < 0) /* deal with occassional race */
685 if (ttl >= type->ks_limit) {
686 if (flags & M_NULLOK) {
687 logmemory(malloc_end, NULL, type, size, flags);
690 panic("%s: malloc limit exceeded", type->ks_shortdesc);
695 * Handle the degenerate size == 0 case. Yes, this does happen.
696 * Return a special pointer. This is to maintain compatibility with
697 * the original malloc implementation. Certain devices, such as the
698 * adaptec driver, not only allocate 0 bytes, they check for NULL and
699 * also realloc() later on. Joy.
702 logmemory(malloc_end, ZERO_LENGTH_PTR, type, size, flags);
703 return(ZERO_LENGTH_PTR);
707 * Handle hysteresis from prior frees here in malloc(). We cannot
708 * safely manipulate the kernel_map in free() due to free() possibly
709 * being called via an IPI message or from sensitive interrupt code.
711 * NOTE: ku_pagecnt must be cleared before we free the slab or we
712 * might race another cpu allocating the kva and setting
715 while (slgd->NFreeZones > ZoneRelsThresh && (flags & M_RNOWAIT) == 0) {
717 if (slgd->NFreeZones > ZoneRelsThresh) { /* crit sect race */
720 z = TAILQ_LAST(&slgd->FreeZones, SLZoneList);
722 TAILQ_REMOVE(&slgd->FreeZones, z, z_Entry);
726 kmem_slab_free(z, ZoneSize); /* may block */
727 atomic_add_int(&ZoneGenAlloc, -ZoneSize / 1024);
733 * XXX handle oversized frees that were queued from kfree().
735 while (TAILQ_FIRST(&slgd->FreeOvZones) && (flags & M_RNOWAIT) == 0) {
737 if ((z = TAILQ_LAST(&slgd->FreeOvZones, SLZoneList)) != NULL) {
740 KKASSERT(z->z_Magic == ZALLOC_OVSZ_MAGIC);
741 TAILQ_REMOVE(&slgd->FreeOvZones, z, z_Entry);
742 tsize = z->z_ChunkSize;
743 kmem_slab_free(z, tsize); /* may block */
744 atomic_add_int(&ZoneBigAlloc, -(int)tsize / 1024);
750 * Handle large allocations directly. There should not be very many of
751 * these so performance is not a big issue.
753 * The backend allocator is pretty nasty on a SMP system. Use the
754 * slab allocator for one and two page-sized chunks even though we lose
755 * some efficiency. XXX maybe fix mmio and the elf loader instead.
757 if (size >= ZoneLimit || ((size & PAGE_MASK) == 0 && size > PAGE_SIZE*2)) {
760 size = round_page(size);
761 chunk = kmem_slab_alloc(size, PAGE_SIZE, flags);
763 logmemory(malloc_end, NULL, type, size, flags);
766 atomic_add_int(&ZoneBigAlloc, (int)size / 1024);
767 flags &= ~M_ZERO; /* result already zero'd if M_ZERO was set */
768 flags |= M_PASSIVE_ZERO;
770 *kup = size / PAGE_SIZE;
776 * Attempt to allocate out of an existing zone. First try the free list,
777 * then allocate out of unallocated space. If we find a good zone move
778 * it to the head of the list so later allocations find it quickly
779 * (we might have thousands of zones in the list).
781 * Note: zoneindex() will panic of size is too large.
783 zi = zoneindex(&size, &align);
784 KKASSERT(zi < NZONES);
787 if ((z = TAILQ_LAST(&slgd->ZoneAry[zi], SLZoneList)) != NULL) {
789 * Locate a chunk - we have to have at least one. If this is the
790 * last chunk go ahead and do the work to retrieve chunks freed
791 * from remote cpus, and if the zone is still empty move it off
794 if (--z->z_NFree <= 0) {
795 KKASSERT(z->z_NFree == 0);
798 * WARNING! This code competes with other cpus. It is ok
799 * for us to not drain RChunks here but we might as well, and
800 * it is ok if more accumulate after we're done.
802 * Set RSignal before pulling rchunks off, indicating that we
803 * will be moving ourselves off of the ZoneAry. Remote ends will
804 * read RSignal before putting rchunks on thus interlocking
805 * their IPI signaling.
807 if (z->z_RChunks == NULL)
808 atomic_swap_int(&z->z_RSignal, 1);
810 clean_zone_rchunks(z);
813 * Remove from the zone list if no free chunks remain.
816 if (z->z_NFree == 0) {
817 TAILQ_REMOVE(&slgd->ZoneAry[zi], z, z_Entry);
824 * Fast path, we have chunks available in z_LChunks.
826 chunk = z->z_LChunks;
828 chunk_mark_allocated(z, chunk);
829 z->z_LChunks = chunk->c_Next;
830 if (z->z_LChunks == NULL)
831 z->z_LChunksp = &z->z_LChunks;
833 slab_record_source(z, file, line);
839 * No chunks are available in LChunks, the free chunk MUST be
840 * in the never-before-used memory area, controlled by UIndex.
842 * The consequences are very serious if our zone got corrupted so
843 * we use an explicit panic rather than a KASSERT.
845 if (z->z_UIndex + 1 != z->z_NMax)
850 if (z->z_UIndex == z->z_UEndIndex)
851 panic("slaballoc: corrupted zone");
853 chunk = (SLChunk *)(z->z_BasePtr + z->z_UIndex * size);
854 if ((z->z_Flags & SLZF_UNOTZEROD) == 0) {
856 flags |= M_PASSIVE_ZERO;
858 chunk_mark_allocated(z, chunk);
860 slab_record_source(z, file, line);
866 * If all zones are exhausted we need to allocate a new zone for this
867 * index. Use M_ZERO to take advantage of pre-zerod pages. Also see
868 * UAlloc use above in regards to M_ZERO. Note that when we are reusing
869 * a zone from the FreeZones list UAlloc'd data will not be zero'd, and
870 * we do not pre-zero it because we do not want to mess up the L1 cache.
872 * At least one subsystem, the tty code (see CROUND) expects power-of-2
873 * allocations to be power-of-2 aligned. We maintain compatibility by
874 * adjusting the base offset below.
880 if ((z = TAILQ_FIRST(&slgd->FreeZones)) != NULL) {
881 TAILQ_REMOVE(&slgd->FreeZones, z, z_Entry);
883 bzero(z, sizeof(SLZone));
884 z->z_Flags |= SLZF_UNOTZEROD;
886 z = kmem_slab_alloc(ZoneSize, ZoneSize, flags|M_ZERO);
889 atomic_add_int(&ZoneGenAlloc, ZoneSize / 1024);
893 * How big is the base structure?
895 #if defined(INVARIANTS)
897 * Make room for z_Bitmap. An exact calculation is somewhat more
898 * complicated so don't make an exact calculation.
900 off = offsetof(SLZone, z_Bitmap[(ZoneSize / size + 31) / 32]);
901 bzero(z->z_Bitmap, (ZoneSize / size + 31) / 8);
903 off = sizeof(SLZone);
907 * Guarentee power-of-2 alignment for power-of-2-sized chunks.
908 * Otherwise properly align the data according to the chunk size.
912 off = roundup2(off, align);
914 z->z_Magic = ZALLOC_SLAB_MAGIC;
916 z->z_NMax = (ZoneSize - off) / size;
917 z->z_NFree = z->z_NMax - 1;
918 z->z_BasePtr = (char *)z + off;
919 z->z_UIndex = z->z_UEndIndex = slgd->JunkIndex % z->z_NMax;
920 z->z_ChunkSize = size;
922 z->z_Cpu = gd->gd_cpuid;
923 z->z_LChunksp = &z->z_LChunks;
925 bcopy(z->z_Sources, z->z_AltSources, sizeof(z->z_Sources));
926 bzero(z->z_Sources, sizeof(z->z_Sources));
928 chunk = (SLChunk *)(z->z_BasePtr + z->z_UIndex * size);
929 TAILQ_INSERT_HEAD(&slgd->ZoneAry[zi], z, z_Entry);
930 if ((z->z_Flags & SLZF_UNOTZEROD) == 0) {
931 flags &= ~M_ZERO; /* already zero'd */
932 flags |= M_PASSIVE_ZERO;
935 *kup = -(z->z_Cpu + 1); /* -1 to -(N+1) */
936 chunk_mark_allocated(z, chunk);
938 slab_record_source(z, file, line);
942 * Slide the base index for initial allocations out of the next
943 * zone we create so we do not over-weight the lower part of the
946 slgd->JunkIndex = (slgd->JunkIndex + ZALLOC_SLAB_SLIDE)
947 & (ZALLOC_MAX_ZONE_SIZE - 1);
951 ++type->ks_use[gd->gd_cpuid].inuse;
952 type->ks_use[gd->gd_cpuid].memuse += size;
953 type->ks_loosememuse += size; /* not MP synchronized */
959 else if ((flags & (M_ZERO|M_PASSIVE_ZERO)) == 0) {
960 if (use_malloc_pattern) {
961 for (i = 0; i < size; i += sizeof(int)) {
962 *(int *)((char *)chunk + i) = -1;
965 chunk->c_Next = (void *)-1; /* avoid accidental double-free check */
968 logmemory(malloc_end, chunk, type, size, flags);
972 logmemory(malloc_end, NULL, type, size, flags);
977 * kernel realloc. (SLAB ALLOCATOR) (MP SAFE)
979 * Generally speaking this routine is not called very often and we do
980 * not attempt to optimize it beyond reusing the same pointer if the
981 * new size fits within the chunking of the old pointer's zone.
985 krealloc_debug(void *ptr, unsigned long size,
986 struct malloc_type *type, int flags,
987 const char *file, int line)
990 krealloc(void *ptr, unsigned long size, struct malloc_type *type, int flags)
999 KKASSERT((flags & M_ZERO) == 0); /* not supported */
1001 if (ptr == NULL || ptr == ZERO_LENGTH_PTR)
1002 return(kmalloc_debug(size, type, flags, file, line));
1009 * Handle oversized allocations. XXX we really should require that a
1010 * size be passed to free() instead of this nonsense.
1014 osize = *kup << PAGE_SHIFT;
1015 if (osize == round_page(size))
1017 if ((nptr = kmalloc_debug(size, type, flags, file, line)) == NULL)
1019 bcopy(ptr, nptr, min(size, osize));
1025 * Get the original allocation's zone. If the new request winds up
1026 * using the same chunk size we do not have to do anything.
1028 z = (SLZone *)((uintptr_t)ptr & ZoneMask);
1031 KKASSERT(z->z_Magic == ZALLOC_SLAB_MAGIC);
1034 * Allocate memory for the new request size. Note that zoneindex has
1035 * already adjusted the request size to the appropriate chunk size, which
1036 * should optimize our bcopy(). Then copy and return the new pointer.
1038 * Resizing a non-power-of-2 allocation to a power-of-2 size does not
1039 * necessary align the result.
1041 * We can only zoneindex (to align size to the chunk size) if the new
1042 * size is not too large.
1044 if (size < ZoneLimit) {
1045 zoneindex(&size, &align);
1046 if (z->z_ChunkSize == size)
1049 if ((nptr = kmalloc_debug(size, type, flags, file, line)) == NULL)
1051 bcopy(ptr, nptr, min(size, z->z_ChunkSize));
1057 * Return the kmalloc limit for this type, in bytes.
1060 kmalloc_limit(struct malloc_type *type)
1062 if (type->ks_limit == 0) {
1064 if (type->ks_limit == 0)
1068 return(type->ks_limit);
1072 * Allocate a copy of the specified string.
1074 * (MP SAFE) (MAY BLOCK)
1078 kstrdup_debug(const char *str, struct malloc_type *type,
1079 const char *file, int line)
1082 kstrdup(const char *str, struct malloc_type *type)
1085 int zlen; /* length inclusive of terminating NUL */
1090 zlen = strlen(str) + 1;
1091 nstr = kmalloc_debug(zlen, type, M_WAITOK, file, line);
1092 bcopy(str, nstr, zlen);
1098 kstrndup_debug(const char *str, size_t maxlen, struct malloc_type *type,
1099 const char *file, int line)
1102 kstrndup(const char *str, size_t maxlen, struct malloc_type *type)
1105 int zlen; /* length inclusive of terminating NUL */
1110 zlen = strnlen(str, maxlen) + 1;
1111 nstr = kmalloc_debug(zlen, type, M_WAITOK, file, line);
1112 bcopy(str, nstr, zlen);
1113 nstr[zlen - 1] = '\0';
1118 * Notify our cpu that a remote cpu has freed some chunks in a zone that
1119 * we own. RCount will be bumped so the memory should be good, but validate
1120 * that it really is.
1124 kfree_remote(void *ptr)
1131 slgd = &mycpu->gd_slab;
1134 KKASSERT(*kup == -((int)mycpuid + 1));
1135 KKASSERT(z->z_RCount > 0);
1136 atomic_subtract_int(&z->z_RCount, 1);
1138 logmemory(free_rem_beg, z, NULL, 0L, 0);
1139 KKASSERT(z->z_Magic == ZALLOC_SLAB_MAGIC);
1140 KKASSERT(z->z_Cpu == mycpu->gd_cpuid);
1144 * Indicate that we will no longer be off of the ZoneAry by
1151 * Atomically extract the bchunks list and then process it back
1152 * into the lchunks list. We want to append our bchunks to the
1153 * lchunks list and not prepend since we likely do not have
1154 * cache mastership of the related data (not that it helps since
1155 * we are using c_Next).
1157 clean_zone_rchunks(z);
1158 if (z->z_NFree && nfree == 0) {
1159 TAILQ_INSERT_HEAD(&slgd->ZoneAry[z->z_ZoneIndex], z, z_Entry);
1163 * If the zone becomes totally free and is not the only zone listed for a
1164 * chunk size we move it to the FreeZones list. We always leave at least
1165 * one zone per chunk size listed, even if it is freeable.
1167 * Since this code can be called from an IPI callback, do *NOT* try to
1168 * mess with kernel_map here. Hysteresis will be performed at malloc()
1171 * Do not move the zone if there is an IPI in_flight (z_RCount != 0),
1172 * otherwise MP races can result in our free_remote code accessing a
1173 * destroyed zone. The remote end interlocks z_RCount with z_RChunks
1174 * so one has to test both z_NFree and z_RCount.
1176 if (z->z_NFree == z->z_NMax && z->z_RCount == 0 &&
1177 (TAILQ_FIRST(&slgd->ZoneAry[z->z_ZoneIndex]) != z ||
1178 TAILQ_NEXT(z, z_Entry))
1182 TAILQ_REMOVE(&slgd->ZoneAry[z->z_ZoneIndex], z, z_Entry);
1184 TAILQ_INSERT_HEAD(&slgd->FreeZones, z, z_Entry);
1189 logmemory(free_rem_end, z, NULL, 0L, 0);
1193 * free (SLAB ALLOCATOR)
1195 * Free a memory block previously allocated by malloc. Note that we do not
1196 * attempt to update ks_loosememuse as MP races could prevent us from
1197 * checking memory limits in malloc.
1202 kfree(void *ptr, struct malloc_type *type)
1207 struct globaldata *gd;
1213 logmemory_quick(free_beg);
1215 slgd = &gd->gd_slab;
1218 panic("trying to free NULL pointer");
1221 * Handle special 0-byte allocations
1223 if (ptr == ZERO_LENGTH_PTR) {
1224 logmemory(free_zero, ptr, type, -1UL, 0);
1225 logmemory_quick(free_end);
1230 * Panic on bad malloc type
1232 if (type->ks_magic != M_MAGIC)
1233 panic("free: malloc type lacks magic");
1236 * Handle oversized allocations. XXX we really should require that a
1237 * size be passed to free() instead of this nonsense.
1239 * This code is never called via an ipi.
1243 size = *kup << PAGE_SHIFT;
1246 KKASSERT(sizeof(weirdary) <= size);
1247 bcopy(weirdary, ptr, sizeof(weirdary));
1250 * NOTE: For oversized allocations we do not record the
1251 * originating cpu. It gets freed on the cpu calling
1252 * kfree(). The statistics are in aggregate.
1254 * note: XXX we have still inherited the interrupts-can't-block
1255 * assumption. An interrupt thread does not bump
1256 * gd_intr_nesting_level so check TDF_INTTHREAD. This is
1257 * primarily until we can fix softupdate's assumptions about free().
1260 --type->ks_use[gd->gd_cpuid].inuse;
1261 type->ks_use[gd->gd_cpuid].memuse -= size;
1262 if (mycpu->gd_intr_nesting_level ||
1263 (gd->gd_curthread->td_flags & TDF_INTTHREAD))
1265 logmemory(free_ovsz_delayed, ptr, type, size, 0);
1267 z->z_Magic = ZALLOC_OVSZ_MAGIC;
1268 z->z_ChunkSize = size;
1270 TAILQ_INSERT_HEAD(&slgd->FreeOvZones, z, z_Entry);
1274 logmemory(free_ovsz, ptr, type, size, 0);
1275 kmem_slab_free(ptr, size); /* may block */
1276 atomic_add_int(&ZoneBigAlloc, -(int)size / 1024);
1278 logmemory_quick(free_end);
1283 * Zone case. Figure out the zone based on the fact that it is
1286 z = (SLZone *)((uintptr_t)ptr & ZoneMask);
1289 KKASSERT(z->z_Magic == ZALLOC_SLAB_MAGIC);
1292 * If we do not own the zone then use atomic ops to free to the
1293 * remote cpu linked list and notify the target zone using a
1296 * The target zone cannot be deallocated while we own a chunk of it,
1297 * so the zone header's storage is stable until the very moment
1298 * we adjust z_RChunks. After that we cannot safely dereference (z).
1300 * (no critical section needed)
1302 if (z->z_CpuGd != gd) {
1304 * Making these adjustments now allow us to avoid passing (type)
1305 * to the remote cpu. Note that inuse/memuse is being
1306 * adjusted on OUR cpu, not the zone cpu, but it should all still
1307 * sum up properly and cancel out.
1310 --type->ks_use[gd->gd_cpuid].inuse;
1311 type->ks_use[gd->gd_cpuid].memuse -= z->z_ChunkSize;
1315 * WARNING! This code competes with other cpus. Once we
1316 * successfully link the chunk to RChunks the remote
1317 * cpu can rip z's storage out from under us.
1319 * Bumping RCount prevents z's storage from getting
1322 rsignal = z->z_RSignal;
1325 atomic_add_int(&z->z_RCount, 1);
1329 bchunk = z->z_RChunks;
1331 chunk->c_Next = bchunk;
1334 if (atomic_cmpset_ptr(&z->z_RChunks, bchunk, chunk))
1339 * We have to signal the remote cpu if our actions will cause
1340 * the remote zone to be placed back on ZoneAry so it can
1341 * move the zone back on.
1343 * We only need to deal with NULL->non-NULL RChunk transitions
1344 * and only if z_RSignal is set. We interlock by reading rsignal
1345 * before adding our chunk to RChunks. This should result in
1346 * virtually no IPI traffic.
1348 * We can use a passive IPI to reduce overhead even further.
1350 if (bchunk == NULL && rsignal) {
1351 logmemory(free_request, ptr, type,
1352 (unsigned long)z->z_ChunkSize, 0);
1353 lwkt_send_ipiq_passive(z->z_CpuGd, kfree_remote, z);
1354 /* z can get ripped out from under us from this point on */
1355 } else if (rsignal) {
1356 atomic_subtract_int(&z->z_RCount, 1);
1357 /* z can get ripped out from under us from this point on */
1359 logmemory_quick(free_end);
1366 logmemory(free_chunk, ptr, type, (unsigned long)z->z_ChunkSize, 0);
1370 chunk_mark_free(z, chunk);
1373 * Put weird data into the memory to detect modifications after freeing,
1374 * illegal pointer use after freeing (we should fault on the odd address),
1375 * and so forth. XXX needs more work, see the old malloc code.
1378 if (z->z_ChunkSize < sizeof(weirdary))
1379 bcopy(weirdary, chunk, z->z_ChunkSize);
1381 bcopy(weirdary, chunk, sizeof(weirdary));
1385 * Add this free non-zero'd chunk to a linked list for reuse. Add
1386 * to the front of the linked list so it is more likely to be
1387 * reallocated, since it is already in our L1 cache.
1390 if ((vm_offset_t)chunk < KvaStart || (vm_offset_t)chunk >= KvaEnd)
1391 panic("BADFREE %p", chunk);
1393 chunk->c_Next = z->z_LChunks;
1394 z->z_LChunks = chunk;
1395 if (chunk->c_Next == NULL)
1396 z->z_LChunksp = &chunk->c_Next;
1399 if (chunk->c_Next && (vm_offset_t)chunk->c_Next < KvaStart)
1404 * Bump the number of free chunks. If it becomes non-zero the zone
1405 * must be added back onto the appropriate list. A fully allocated
1406 * zone that sees its first free is considered 'mature' and is placed
1407 * at the head, giving the system time to potentially free the remaining
1408 * entries even while other allocations are going on and making the zone
1411 if (z->z_NFree++ == 0) {
1413 TAILQ_INSERT_TAIL(&slgd->ZoneAry[z->z_ZoneIndex], z, z_Entry);
1415 TAILQ_INSERT_HEAD(&slgd->ZoneAry[z->z_ZoneIndex], z, z_Entry);
1418 --type->ks_use[z->z_Cpu].inuse;
1419 type->ks_use[z->z_Cpu].memuse -= z->z_ChunkSize;
1421 check_zone_free(slgd, z);
1422 logmemory_quick(free_end);
1427 * Cleanup slabs which are hanging around due to RChunks or which are wholely
1428 * free and can be moved to the free list if not moved by other means.
1430 * Called once every 10 seconds on all cpus.
1435 SLGlobalData *slgd = &mycpu->gd_slab;
1440 for (i = 0; i < NZONES; ++i) {
1441 if ((z = TAILQ_FIRST(&slgd->ZoneAry[i])) == NULL)
1449 * Shift all RChunks to the end of the LChunks list. This is
1450 * an O(1) operation.
1452 * Then free the zone if possible.
1454 clean_zone_rchunks(z);
1455 z = check_zone_free(slgd, z);
1461 #if defined(INVARIANTS)
1464 * Helper routines for sanity checks
1468 chunk_mark_allocated(SLZone *z, void *chunk)
1470 int bitdex = ((char *)chunk - (char *)z->z_BasePtr) / z->z_ChunkSize;
1473 KKASSERT((((intptr_t)chunk ^ (intptr_t)z) & ZoneMask) == 0);
1474 KASSERT(bitdex >= 0 && bitdex < z->z_NMax,
1475 ("memory chunk %p bit index %d is illegal", chunk, bitdex));
1476 bitptr = &z->z_Bitmap[bitdex >> 5];
1478 KASSERT((*bitptr & (1 << bitdex)) == 0,
1479 ("memory chunk %p is already allocated!", chunk));
1480 *bitptr |= 1 << bitdex;
1485 chunk_mark_free(SLZone *z, void *chunk)
1487 int bitdex = ((char *)chunk - (char *)z->z_BasePtr) / z->z_ChunkSize;
1490 KKASSERT((((intptr_t)chunk ^ (intptr_t)z) & ZoneMask) == 0);
1491 KASSERT(bitdex >= 0 && bitdex < z->z_NMax,
1492 ("memory chunk %p bit index %d is illegal!", chunk, bitdex));
1493 bitptr = &z->z_Bitmap[bitdex >> 5];
1495 KASSERT((*bitptr & (1 << bitdex)) != 0,
1496 ("memory chunk %p is already free!", chunk));
1497 *bitptr &= ~(1 << bitdex);
1505 * Directly allocate and wire kernel memory in PAGE_SIZE chunks with the
1506 * specified alignment. M_* flags are expected in the flags field.
1508 * Alignment must be a multiple of PAGE_SIZE.
1510 * NOTE! XXX For the moment we use vm_map_entry_reserve/release(),
1511 * but when we move zalloc() over to use this function as its backend
1512 * we will have to switch to kreserve/krelease and call reserve(0)
1513 * after the new space is made available.
1515 * Interrupt code which has preempted other code is not allowed to
1516 * use PQ_CACHE pages. However, if an interrupt thread is run
1517 * non-preemptively or blocks and then runs non-preemptively, then
1518 * it is free to use PQ_CACHE pages. <--- may not apply any longer XXX
1521 kmem_slab_alloc(vm_size_t size, vm_offset_t align, int flags)
1525 int count, vmflags, base_vmflags;
1526 vm_page_t mbase = NULL;
1530 size = round_page(size);
1531 addr = vm_map_min(&kernel_map);
1533 count = vm_map_entry_reserve(MAP_RESERVE_COUNT);
1535 vm_map_lock(&kernel_map);
1536 if (vm_map_findspace(&kernel_map, addr, size, align, 0, &addr)) {
1537 vm_map_unlock(&kernel_map);
1538 if ((flags & M_NULLOK) == 0)
1539 panic("kmem_slab_alloc(): kernel_map ran out of space!");
1540 vm_map_entry_release(count);
1546 * kernel_object maps 1:1 to kernel_map.
1548 vm_object_hold(&kernel_object);
1549 vm_object_reference_locked(&kernel_object);
1550 vm_map_insert(&kernel_map, &count,
1551 &kernel_object, NULL,
1552 addr, addr, addr + size,
1555 VM_PROT_ALL, VM_PROT_ALL, 0);
1556 vm_object_drop(&kernel_object);
1557 vm_map_set_wired_quick(&kernel_map, addr, size, &count);
1558 vm_map_unlock(&kernel_map);
1564 base_vmflags |= VM_ALLOC_ZERO;
1565 if (flags & M_USE_RESERVE)
1566 base_vmflags |= VM_ALLOC_SYSTEM;
1567 if (flags & M_USE_INTERRUPT_RESERVE)
1568 base_vmflags |= VM_ALLOC_INTERRUPT;
1569 if ((flags & (M_RNOWAIT|M_WAITOK)) == 0) {
1570 panic("kmem_slab_alloc: bad flags %08x (%p)",
1571 flags, ((int **)&size)[-1]);
1575 * Allocate the pages. Do not map them yet. VM_ALLOC_NORMAL can only
1576 * be set if we are not preempting.
1578 * VM_ALLOC_SYSTEM is automatically set if we are preempting and
1579 * M_WAITOK was specified as an alternative (i.e. M_USE_RESERVE is
1580 * implied in this case), though I'm not sure if we really need to
1583 vmflags = base_vmflags;
1584 if (flags & M_WAITOK) {
1585 if (td->td_preempted)
1586 vmflags |= VM_ALLOC_SYSTEM;
1588 vmflags |= VM_ALLOC_NORMAL;
1591 vm_object_hold(&kernel_object);
1592 for (i = 0; i < size; i += PAGE_SIZE) {
1593 m = vm_page_alloc(&kernel_object, OFF_TO_IDX(addr + i), vmflags);
1598 * If the allocation failed we either return NULL or we retry.
1600 * If M_WAITOK is specified we wait for more memory and retry.
1601 * If M_WAITOK is specified from a preemption we yield instead of
1602 * wait. Livelock will not occur because the interrupt thread
1603 * will not be preempting anyone the second time around after the
1607 if (flags & M_WAITOK) {
1608 if (td->td_preempted) {
1613 i -= PAGE_SIZE; /* retry */
1621 * Check and deal with an allocation failure
1626 m = vm_page_lookup(&kernel_object, OFF_TO_IDX(addr + i));
1627 /* page should already be busy */
1630 vm_map_lock(&kernel_map);
1631 vm_map_delete(&kernel_map, addr, addr + size, &count);
1632 vm_map_unlock(&kernel_map);
1633 vm_object_drop(&kernel_object);
1635 vm_map_entry_release(count);
1643 * NOTE: The VM pages are still busied. mbase points to the first one
1644 * but we have to iterate via vm_page_next()
1646 vm_object_drop(&kernel_object);
1650 * Enter the pages into the pmap and deal with M_ZERO.
1657 * page should already be busy
1659 m->valid = VM_PAGE_BITS_ALL;
1661 pmap_enter(&kernel_pmap, addr + i, m, VM_PROT_ALL | VM_PROT_NOSYNC,
1664 pagezero((char *)addr + i);
1665 KKASSERT(m->flags & (PG_WRITEABLE | PG_MAPPED));
1666 vm_page_flag_set(m, PG_REFERENCED);
1670 vm_object_hold(&kernel_object);
1671 m = vm_page_next(m);
1672 vm_object_drop(&kernel_object);
1675 vm_map_entry_release(count);
1676 atomic_add_long(&SlabsAllocated, 1);
1677 return((void *)addr);
1684 kmem_slab_free(void *ptr, vm_size_t size)
1687 vm_map_remove(&kernel_map, (vm_offset_t)ptr, (vm_offset_t)ptr + size);
1688 atomic_add_long(&SlabsFreed, 1);
1693 kmalloc_cachealign(unsigned long size_alloc, struct malloc_type *type,
1696 #if (__VM_CACHELINE_SIZE == 32)
1697 #define CAN_CACHEALIGN(sz) ((sz) >= 256)
1698 #elif (__VM_CACHELINE_SIZE == 64)
1699 #define CAN_CACHEALIGN(sz) ((sz) >= 512)
1700 #elif (__VM_CACHELINE_SIZE == 128)
1701 #define CAN_CACHEALIGN(sz) ((sz) >= 1024)
1703 #error "unsupported cacheline size"
1708 if (size_alloc < __VM_CACHELINE_SIZE)
1709 size_alloc = __VM_CACHELINE_SIZE;
1710 else if (!CAN_CACHEALIGN(size_alloc))
1711 flags |= M_POWEROF2;
1713 ret = kmalloc(size_alloc, type, flags);
1714 KASSERT(((uintptr_t)ret & (__VM_CACHELINE_SIZE - 1)) == 0,
1715 ("%p(%lu) not cacheline %d aligned",
1716 ret, size_alloc, __VM_CACHELINE_SIZE));
1719 #undef CAN_CACHEALIGN