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Diffstat (limited to 'kern/slab.c')
| -rw-r--r-- | kern/slab.c | 1686 |
1 files changed, 1686 insertions, 0 deletions
diff --git a/kern/slab.c b/kern/slab.c new file mode 100644 index 0000000..dc44e42 --- /dev/null +++ b/kern/slab.c @@ -0,0 +1,1686 @@ +/* + * Copyright (c) 2011 Free Software Foundation. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +/* + * Copyright (c) 2010, 2011 Richard Braun. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * + * Object caching and general purpose memory allocator. + * + * This allocator is based on the paper "The Slab Allocator: An Object-Caching + * Kernel Memory Allocator" by Jeff Bonwick. + * + * It allows the allocation of objects (i.e. fixed-size typed buffers) from + * caches and is efficient in both space and time. This implementation follows + * many of the indications from the paper mentioned. The most notable + * differences are outlined below. + * + * The per-cache self-scaling hash table for buffer-to-bufctl conversion, + * described in 3.2.3 "Slab Layout for Large Objects", has been replaced by + * a red-black tree storing slabs, sorted by address. The use of a + * self-balancing tree for buffer-to-slab conversions provides a few advantages + * over a hash table. Unlike a hash table, a BST provides a "lookup nearest" + * operation, so obtaining the slab data (whether it is embedded in the slab or + * off slab) from a buffer address simply consists of a "lookup nearest towards + * 0" tree search. Finally, a self-balancing tree is a true self-scaling data + * structure, whereas a hash table requires periodic maintenance and complete + * resizing, which is expensive. The only drawback is that releasing a buffer + * to the slab layer takes logarithmic time instead of constant time. + * + * This implementation uses per-cpu pools of objects, which service most + * allocation requests. These pools act as caches (but are named differently + * to avoid confusion with CPU caches) that reduce contention on multiprocessor + * systems. When a pool is empty and cannot provide an object, it is filled by + * transferring multiple objects from the slab layer. The symmetric case is + * handled likewise. + */ + +#include <string.h> +#include <kern/assert.h> +#include <kern/mach_clock.h> +#include <kern/macros.h> +#include <kern/printf.h> +#include <kern/slab.h> +#include <kern/kalloc.h> +#include <kern/cpu_number.h> +#include <kern/mach_debug.server.h> +#include <mach/vm_param.h> +#include <mach/machine/vm_types.h> +#include <vm/vm_kern.h> +#include <vm/vm_page.h> +#include <vm/vm_types.h> +#include <sys/types.h> + +#ifdef MACH_DEBUG +#include <mach_debug/slab_info.h> +#endif + +/* + * Utility macros. + */ +#define P2ALIGNED(x, a) (((x) & ((a) - 1)) == 0) +#define ISP2(x) P2ALIGNED(x, x) +#define P2ALIGN(x, a) ((x) & -(a)) +#define P2ROUND(x, a) (-(-(x) & -(a))) +#define P2END(x, a) (-(~(x) & -(a))) +#define likely(expr) __builtin_expect(!!(expr), 1) +#define unlikely(expr) __builtin_expect(!!(expr), 0) + +/* + * Minimum required alignment. + */ +#define KMEM_ALIGN_MIN 8 + +/* + * Special buffer size under which slab data is unconditionnally allocated + * from its associated slab. + */ +#define KMEM_BUF_SIZE_THRESHOLD (PAGE_SIZE / 8) + +/* + * Time (in ticks) between two garbage collection operations. + */ +#define KMEM_GC_INTERVAL (5 * hz) + +/* + * The transfer size of a CPU pool is computed by dividing the pool size by + * this value. + */ +#define KMEM_CPU_POOL_TRANSFER_RATIO 2 + +/* + * Redzone guard word. + */ +#ifdef __LP64__ +#if _HOST_BIG_ENDIAN +#define KMEM_REDZONE_WORD 0xfeedfacefeedfaceUL +#else /* _HOST_BIG_ENDIAN */ +#define KMEM_REDZONE_WORD 0xcefaedfecefaedfeUL +#endif /* _HOST_BIG_ENDIAN */ +#else /* __LP64__ */ +#if _HOST_BIG_ENDIAN +#define KMEM_REDZONE_WORD 0xfeedfaceUL +#else /* _HOST_BIG_ENDIAN */ +#define KMEM_REDZONE_WORD 0xcefaedfeUL +#endif /* _HOST_BIG_ENDIAN */ +#endif /* __LP64__ */ + +/* + * Redzone byte for padding. + */ +#define KMEM_REDZONE_BYTE 0xbb + +/* + * Shift for the first kalloc cache size. + */ +#define KALLOC_FIRST_SHIFT 5 + +/* + * Number of caches backing general purpose allocations. + */ +#define KALLOC_NR_CACHES 13 + +/* + * Values the buftag state member can take. + */ +#ifdef __LP64__ +#if _HOST_BIG_ENDIAN +#define KMEM_BUFTAG_ALLOC 0xa110c8eda110c8edUL +#define KMEM_BUFTAG_FREE 0xf4eeb10cf4eeb10cUL +#else /* _HOST_BIG_ENDIAN */ +#define KMEM_BUFTAG_ALLOC 0xedc810a1edc810a1UL +#define KMEM_BUFTAG_FREE 0x0cb1eef40cb1eef4UL +#endif /* _HOST_BIG_ENDIAN */ +#else /* __LP64__ */ +#if _HOST_BIG_ENDIAN +#define KMEM_BUFTAG_ALLOC 0xa110c8edUL +#define KMEM_BUFTAG_FREE 0xf4eeb10cUL +#else /* _HOST_BIG_ENDIAN */ +#define KMEM_BUFTAG_ALLOC 0xedc810a1UL +#define KMEM_BUFTAG_FREE 0x0cb1eef4UL +#endif /* _HOST_BIG_ENDIAN */ +#endif /* __LP64__ */ + +/* + * Free and uninitialized patterns. + * + * These values are unconditionnally 64-bit wide since buffers are at least + * 8-byte aligned. + */ +#if _HOST_BIG_ENDIAN +#define KMEM_FREE_PATTERN 0xdeadbeefdeadbeefULL +#define KMEM_UNINIT_PATTERN 0xbaddcafebaddcafeULL +#else /* _HOST_BIG_ENDIAN */ +#define KMEM_FREE_PATTERN 0xefbeaddeefbeaddeULL +#define KMEM_UNINIT_PATTERN 0xfecaddbafecaddbaULL +#endif /* _HOST_BIG_ENDIAN */ + +/* + * Cache flags. + * + * The flags don't change once set and can be tested without locking. + */ +#define KMEM_CF_SLAB_EXTERNAL 0x01 /* Slab data is off slab */ +#define KMEM_CF_PHYSMEM 0x02 /* Allocate from physical memory */ +#define KMEM_CF_DIRECT 0x04 /* Direct buf-to-slab translation + (implies !KMEM_CF_SLAB_EXTERNAL) */ +#define KMEM_CF_USE_TREE 0x08 /* Use red-black tree to track slab + data */ +#define KMEM_CF_USE_PAGE 0x10 /* Use page private data to track slab + data (implies KMEM_CF_SLAB_EXTERNAL + and KMEM_CF_PHYSMEM) */ +#define KMEM_CF_VERIFY 0x20 /* Debugging facilities enabled + (implies KMEM_CF_USE_TREE) */ + +/* + * Options for kmem_cache_alloc_verify(). + */ +#define KMEM_AV_NOCONSTRUCT 0 +#define KMEM_AV_CONSTRUCT 1 + +/* + * Error codes for kmem_cache_error(). + */ +#define KMEM_ERR_INVALID 0 /* Invalid address being freed */ +#define KMEM_ERR_DOUBLEFREE 1 /* Freeing already free address */ +#define KMEM_ERR_BUFTAG 2 /* Invalid buftag content */ +#define KMEM_ERR_MODIFIED 3 /* Buffer modified while free */ +#define KMEM_ERR_REDZONE 4 /* Redzone violation */ + +#if SLAB_USE_CPU_POOLS +/* + * Available CPU pool types. + * + * For each entry, the CPU pool size applies from the entry buf_size + * (excluded) up to (and including) the buf_size of the preceding entry. + * + * See struct kmem_cpu_pool_type for a description of the values. + */ +static struct kmem_cpu_pool_type kmem_cpu_pool_types[] = { + { 32768, 1, 0, NULL }, + { 4096, 8, CPU_L1_SIZE, NULL }, + { 256, 64, CPU_L1_SIZE, NULL }, + { 0, 128, CPU_L1_SIZE, NULL } +}; + +/* + * Caches where CPU pool arrays are allocated from. + */ +static struct kmem_cache kmem_cpu_array_caches[ARRAY_SIZE(kmem_cpu_pool_types)]; +#endif /* SLAB_USE_CPU_POOLS */ + +/* + * Cache for off slab data. + */ +static struct kmem_cache kmem_slab_cache; + +/* + * General purpose caches array. + */ +static struct kmem_cache kalloc_caches[KALLOC_NR_CACHES]; + +/* + * List of all caches managed by the allocator. + */ +static struct list kmem_cache_list; +static unsigned int kmem_nr_caches; +static simple_lock_data_t __attribute__((used)) kmem_cache_list_lock; + +/* + * Time of the last memory reclaim, in clock ticks. + */ +static unsigned long kmem_gc_last_tick; + +#define kmem_error(format, ...) \ + panic("mem: error: %s(): " format "\n", __func__, \ + ## __VA_ARGS__) + +#define kmem_warn(format, ...) \ + printf("mem: warning: %s(): " format "\n", __func__, \ + ## __VA_ARGS__) + +#define kmem_print(format, ...) \ + printf(format "\n", ## __VA_ARGS__) + +static void kmem_cache_error(struct kmem_cache *cache, void *buf, int error, + void *arg); +static void * kmem_cache_alloc_from_slab(struct kmem_cache *cache); +static void kmem_cache_free_to_slab(struct kmem_cache *cache, void *buf); + +static void * kmem_buf_verify_bytes(void *buf, void *pattern, size_t size) +{ + char *ptr, *pattern_ptr, *end; + + end = buf + size; + + for (ptr = buf, pattern_ptr = pattern; ptr < end; ptr++, pattern_ptr++) + if (*ptr != *pattern_ptr) + return ptr; + + return NULL; +} + +static void * kmem_buf_verify(void *buf, uint64_t pattern, vm_size_t size) +{ + uint64_t *ptr, *end; + + assert(P2ALIGNED((unsigned long)buf, sizeof(uint64_t))); + assert(P2ALIGNED(size, sizeof(uint64_t))); + + end = buf + size; + + for (ptr = buf; ptr < end; ptr++) + if (*ptr != pattern) + return kmem_buf_verify_bytes(ptr, &pattern, sizeof(pattern)); + + return NULL; +} + +static void kmem_buf_fill(void *buf, uint64_t pattern, size_t size) +{ + uint64_t *ptr, *end; + + assert(P2ALIGNED((unsigned long)buf, sizeof(uint64_t))); + assert(P2ALIGNED(size, sizeof(uint64_t))); + + end = buf + size; + + for (ptr = buf; ptr < end; ptr++) + *ptr = pattern; +} + +static void * kmem_buf_verify_fill(void *buf, uint64_t old, uint64_t new, + size_t size) +{ + uint64_t *ptr, *end; + + assert(P2ALIGNED((unsigned long)buf, sizeof(uint64_t))); + assert(P2ALIGNED(size, sizeof(uint64_t))); + + end = buf + size; + + for (ptr = buf; ptr < end; ptr++) { + if (*ptr != old) + return kmem_buf_verify_bytes(ptr, &old, sizeof(old)); + + *ptr = new; + } + + return NULL; +} + +static inline union kmem_bufctl * +kmem_buf_to_bufctl(void *buf, struct kmem_cache *cache) +{ + return (union kmem_bufctl *)(buf + cache->bufctl_dist); +} + +static inline struct kmem_buftag * +kmem_buf_to_buftag(void *buf, struct kmem_cache *cache) +{ + return (struct kmem_buftag *)(buf + cache->buftag_dist); +} + +static inline void * kmem_bufctl_to_buf(union kmem_bufctl *bufctl, + struct kmem_cache *cache) +{ + return (void *)bufctl - cache->bufctl_dist; +} + +static vm_offset_t +kmem_pagealloc_physmem(vm_size_t size) +{ + struct vm_page *page; + + assert(size == PAGE_SIZE); + + for (;;) { + page = vm_page_grab(VM_PAGE_DIRECTMAP); + + if (page != NULL) + break; + + VM_PAGE_WAIT(NULL); + } + + return phystokv(vm_page_to_pa(page)); +} + +static void +kmem_pagefree_physmem(vm_offset_t addr, vm_size_t size) +{ + struct vm_page *page; + + assert(size == PAGE_SIZE); + page = vm_page_lookup_pa(kvtophys(addr)); + assert(page != NULL); + vm_page_release(page, FALSE, FALSE); +} + +static vm_offset_t +kmem_pagealloc_virtual(vm_size_t size, vm_size_t align) +{ + vm_offset_t addr; + kern_return_t kr; + + assert(size > PAGE_SIZE); + size = vm_page_round(size); + + if (align <= PAGE_SIZE) + kr = kmem_alloc_wired(kernel_map, &addr, size); + else + kr = kmem_alloc_aligned(kernel_map, &addr, size); + + if (kr != KERN_SUCCESS) + return 0; + + return addr; +} + +static void +kmem_pagefree_virtual(vm_offset_t addr, vm_size_t size) +{ + if (addr < kernel_virtual_start || addr + size > kernel_virtual_end) + panic("kmem_pagefree_virtual(%lx-%lx) falls in physical memory area!\n", + (unsigned long) addr, (unsigned long) addr + size); + assert(size > PAGE_SIZE); + size = vm_page_round(size); + kmem_free(kernel_map, addr, size); +} + +static vm_offset_t +kmem_pagealloc(vm_size_t size, vm_size_t align, int flags) +{ + assert(align <= size); + return (flags & KMEM_CF_PHYSMEM) + ? kmem_pagealloc_physmem(size) + : kmem_pagealloc_virtual(size, align); +} + +static void +kmem_pagefree(vm_offset_t addr, vm_size_t size, int flags) +{ + return (flags & KMEM_CF_PHYSMEM) + ? kmem_pagefree_physmem(addr, size) + : kmem_pagefree_virtual(addr, size); +} + +static void kmem_slab_create_verify(struct kmem_slab *slab, + struct kmem_cache *cache) +{ + struct kmem_buftag *buftag; + size_t buf_size; + unsigned long buffers; + void *buf; + + buf_size = cache->buf_size; + buf = slab->addr; + buftag = kmem_buf_to_buftag(buf, cache); + + for (buffers = cache->bufs_per_slab; buffers != 0; buffers--) { + kmem_buf_fill(buf, KMEM_FREE_PATTERN, cache->bufctl_dist); + buftag->state = KMEM_BUFTAG_FREE; + buf += buf_size; + buftag = kmem_buf_to_buftag(buf, cache); + } +} + +/* + * Create an empty slab for a cache. + * + * The caller must drop all locks before calling this function. + */ +static struct kmem_slab * kmem_slab_create(struct kmem_cache *cache, + size_t color) +{ + struct kmem_slab *slab; + union kmem_bufctl *bufctl; + size_t buf_size; + unsigned long buffers; + vm_offset_t slab_buf; + + slab_buf = kmem_pagealloc(cache->slab_size, cache->align, cache->flags); + + if (slab_buf == 0) + return NULL; + + if (cache->flags & KMEM_CF_SLAB_EXTERNAL) { + slab = (struct kmem_slab *)kmem_cache_alloc(&kmem_slab_cache); + + if (slab == NULL) { + kmem_pagefree(slab_buf, cache->slab_size, cache->flags); + return NULL; + } + + if (cache->flags & KMEM_CF_USE_PAGE) { + struct vm_page *page; + + page = vm_page_lookup_pa(kvtophys(slab_buf)); + assert(page != NULL); + vm_page_set_priv(page, slab); + } + } else { + slab = (struct kmem_slab *)(slab_buf + cache->slab_size) - 1; + } + + slab->cache = cache; + list_node_init(&slab->list_node); + rbtree_node_init(&slab->tree_node); + slab->nr_refs = 0; + slab->first_free = NULL; + slab->addr = (void *)(slab_buf + color); + + buf_size = cache->buf_size; + bufctl = kmem_buf_to_bufctl(slab->addr, cache); + + for (buffers = cache->bufs_per_slab; buffers != 0; buffers--) { + bufctl->next = slab->first_free; + slab->first_free = bufctl; + bufctl = (union kmem_bufctl *)((void *)bufctl + buf_size); + } + + if (cache->flags & KMEM_CF_VERIFY) + kmem_slab_create_verify(slab, cache); + + return slab; +} + +static void kmem_slab_destroy_verify(struct kmem_slab *slab, + struct kmem_cache *cache) +{ + struct kmem_buftag *buftag; + size_t buf_size; + unsigned long buffers; + void *buf, *addr; + + buf_size = cache->buf_size; + buf = slab->addr; + buftag = kmem_buf_to_buftag(buf, cache); + + for (buffers = cache->bufs_per_slab; buffers != 0; buffers--) { + if (buftag->state != KMEM_BUFTAG_FREE) + kmem_cache_error(cache, buf, KMEM_ERR_BUFTAG, buftag); + + addr = kmem_buf_verify(buf, KMEM_FREE_PATTERN, cache->bufctl_dist); + + if (addr != NULL) + kmem_cache_error(cache, buf, KMEM_ERR_MODIFIED, addr); + + buf += buf_size; + buftag = kmem_buf_to_buftag(buf, cache); + } +} + +/* + * Destroy a slab. + * + * The caller must drop all locks before calling this function. + */ +static void kmem_slab_destroy(struct kmem_slab *slab, struct kmem_cache *cache) +{ + vm_offset_t slab_buf; + + assert(slab->nr_refs == 0); + assert(slab->first_free != NULL); + + if (cache->flags & KMEM_CF_VERIFY) + kmem_slab_destroy_verify(slab, cache); + + slab_buf = (vm_offset_t)P2ALIGN((unsigned long)slab->addr, PAGE_SIZE); + + if (cache->flags & KMEM_CF_SLAB_EXTERNAL) { + if (cache->flags & KMEM_CF_USE_PAGE) { + struct vm_page *page; + + /* Not strictly needed, but let's increase safety */ + page = vm_page_lookup_pa(kvtophys(slab_buf)); + assert(page != NULL); + vm_page_set_priv(page, NULL); + } + + kmem_cache_free(&kmem_slab_cache, (vm_offset_t)slab); + } + + kmem_pagefree(slab_buf, cache->slab_size, cache->flags); +} + +static inline int kmem_slab_cmp_lookup(const void *addr, + const struct rbtree_node *node) +{ + struct kmem_slab *slab; + + slab = rbtree_entry(node, struct kmem_slab, tree_node); + + if (addr == slab->addr) + return 0; + else if (addr < slab->addr) + return -1; + else + return 1; +} + +static inline int kmem_slab_cmp_insert(const struct rbtree_node *a, + const struct rbtree_node *b) +{ + struct kmem_slab *slab; + + slab = rbtree_entry(a, struct kmem_slab, tree_node); + return kmem_slab_cmp_lookup(slab->addr, b); +} + +#if SLAB_USE_CPU_POOLS +static void kmem_cpu_pool_init(struct kmem_cpu_pool *cpu_pool, + struct kmem_cache *cache) +{ + simple_lock_init(&cpu_pool->lock); + cpu_pool->flags = cache->flags; + cpu_pool->size = 0; + cpu_pool->transfer_size = 0; + cpu_pool->nr_objs = 0; + cpu_pool->array = NULL; +} + +/* + * Return a CPU pool. + * + * This function will generally return the pool matching the CPU running the + * calling thread. Because of context switches and thread migration, the + * caller might be running on another processor after this function returns. + * Although not optimal, this should rarely happen, and it doesn't affect the + * allocator operations in any other way, as CPU pools are always valid, and + * their access is serialized by a lock. + */ +static inline struct kmem_cpu_pool * kmem_cpu_pool_get(struct kmem_cache *cache) +{ + return &cache->cpu_pools[cpu_number()]; +} + +static inline void kmem_cpu_pool_build(struct kmem_cpu_pool *cpu_pool, + struct kmem_cache *cache, void **array) +{ + cpu_pool->size = cache->cpu_pool_type->array_size; + cpu_pool->transfer_size = (cpu_pool->size + + KMEM_CPU_POOL_TRANSFER_RATIO - 1) + / KMEM_CPU_POOL_TRANSFER_RATIO; + cpu_pool->array = array; +} + +static inline void * kmem_cpu_pool_pop(struct kmem_cpu_pool *cpu_pool) +{ + cpu_pool->nr_objs--; + return cpu_pool->array[cpu_pool->nr_objs]; +} + +static inline void kmem_cpu_pool_push(struct kmem_cpu_pool *cpu_pool, void *obj) +{ + cpu_pool->array[cpu_pool->nr_objs] = obj; + cpu_pool->nr_objs++; +} + +static int kmem_cpu_pool_fill(struct kmem_cpu_pool *cpu_pool, + struct kmem_cache *cache) +{ + kmem_cache_ctor_t ctor; + void *buf; + int i; + + ctor = (cpu_pool->flags & KMEM_CF_VERIFY) ? NULL : cache->ctor; + + simple_lock(&cache->lock); + + for (i = 0; i < cpu_pool->transfer_size; i++) { + buf = kmem_cache_alloc_from_slab(cache); + + if (buf == NULL) + break; + + if (ctor != NULL) + ctor(buf); + + kmem_cpu_pool_push(cpu_pool, buf); + } + + simple_unlock(&cache->lock); + + return i; +} + +static void kmem_cpu_pool_drain(struct kmem_cpu_pool *cpu_pool, + struct kmem_cache *cache) +{ + void *obj; + int i; + + simple_lock(&cache->lock); + + for (i = cpu_pool->transfer_size; i > 0; i--) { + obj = kmem_cpu_pool_pop(cpu_pool); + kmem_cache_free_to_slab(cache, obj); + } + + simple_unlock(&cache->lock); +} +#endif /* SLAB_USE_CPU_POOLS */ + +static void kmem_cache_error(struct kmem_cache *cache, void *buf, int error, + void *arg) +{ + struct kmem_buftag *buftag; + + kmem_warn("cache: %s, buffer: %p", cache->name, (void *)buf); + + switch(error) { + case KMEM_ERR_INVALID: + kmem_error("freeing invalid address"); + break; + case KMEM_ERR_DOUBLEFREE: + kmem_error("attempting to free the same address twice"); + break; + case KMEM_ERR_BUFTAG: + buftag = arg; + kmem_error("invalid buftag content, buftag state: %p", + (void *)buftag->state); + break; + case KMEM_ERR_MODIFIED: + kmem_error("free buffer modified, fault address: %p, " + "offset in buffer: %td", arg, arg - buf); + break; + case KMEM_ERR_REDZONE: + kmem_error("write beyond end of buffer, fault address: %p, " + "offset in buffer: %td", arg, arg - buf); + break; + default: + kmem_error("unknown error"); + } + + /* + * Never reached. + */ +} + +/* + * Compute properties such as slab size for the given cache. + * + * Once the slab size is known, this function sets the related properties + * (buffers per slab and maximum color). It can also set some KMEM_CF_xxx + * flags depending on the resulting layout. + */ +static void kmem_cache_compute_properties(struct kmem_cache *cache, int flags) +{ + size_t size, waste; + int embed; + + if (cache->buf_size < KMEM_BUF_SIZE_THRESHOLD) + flags |= KMEM_CACHE_NOOFFSLAB; + + cache->slab_size = PAGE_SIZE; + + for (;;) { + if (flags & KMEM_CACHE_NOOFFSLAB) + embed = 1; + else { + waste = cache->slab_size % cache->buf_size; + embed = (sizeof(struct kmem_slab) <= waste); + } + + size = cache->slab_size; + + if (embed) + size -= sizeof(struct kmem_slab); + + if (size >= cache->buf_size) + break; + + cache->slab_size += PAGE_SIZE; + } + + cache->bufs_per_slab = size / cache->buf_size; + cache->color_max = size % cache->buf_size; + + if (cache->color_max >= PAGE_SIZE) + cache->color_max = 0; + + if (!embed) + cache->flags |= KMEM_CF_SLAB_EXTERNAL; + + if ((flags & KMEM_CACHE_PHYSMEM) || (cache->slab_size == PAGE_SIZE)) { + cache->flags |= KMEM_CF_PHYSMEM; + + /* + * Avoid using larger-than-page slabs backed by the direct physical + * mapping to completely prevent physical memory fragmentation from + * making slab allocations fail. + */ + if (cache->slab_size != PAGE_SIZE) + panic("slab: invalid cache parameters"); + } + + if (cache->flags & KMEM_CF_VERIFY) + cache->flags |= KMEM_CF_USE_TREE; + + if (cache->flags & KMEM_CF_SLAB_EXTERNAL) { + if (cache->flags & KMEM_CF_PHYSMEM) + cache->flags |= KMEM_CF_USE_PAGE; + else + cache->flags |= KMEM_CF_USE_TREE; + } else { + if (cache->slab_size == PAGE_SIZE) + cache->flags |= KMEM_CF_DIRECT; + else + cache->flags |= KMEM_CF_USE_TREE; + } +} + +void kmem_cache_init(struct kmem_cache *cache, const char *name, + size_t obj_size, size_t align, + kmem_cache_ctor_t ctor, int flags) +{ +#if SLAB_USE_CPU_POOLS + struct kmem_cpu_pool_type *cpu_pool_type; + size_t i; +#endif /* SLAB_USE_CPU_POOLS */ + size_t buf_size; + + cache->flags = 0; +#if SLAB_VERIFY + if (obj_size < PAGE_SIZE - sizeof(union kmem_bufctl) + sizeof(struct kmem_buftag)) + cache->flags |= KMEM_CF_VERIFY; +#endif /* SLAB_VERIFY */ + + if (flags & KMEM_CACHE_VERIFY) + cache->flags |= KMEM_CF_VERIFY; + + if (align < KMEM_ALIGN_MIN) + align = KMEM_ALIGN_MIN; + + assert(obj_size > 0); + assert(ISP2(align)); + + buf_size = P2ROUND(obj_size, align); + + simple_lock_init(&cache->lock); + list_node_init(&cache->node); + list_init(&cache->partial_slabs); + list_init(&cache->free_slabs); + rbtree_init(&cache->active_slabs); + cache->obj_size = obj_size; + cache->align = align; + cache->buf_size = buf_size; + cache->bufctl_dist = buf_size - sizeof(union kmem_bufctl); + cache->color = 0; + cache->nr_objs = 0; + cache->nr_bufs = 0; + cache->nr_slabs = 0; + cache->nr_free_slabs = 0; + cache->ctor = ctor; + strncpy(cache->name, name, sizeof(cache->name)); + cache->name[sizeof(cache->name) - 1] = '\0'; + cache->buftag_dist = 0; + cache->redzone_pad = 0; + + if (cache->flags & KMEM_CF_VERIFY) { + cache->bufctl_dist = buf_size; + cache->buftag_dist = cache->bufctl_dist + sizeof(union kmem_bufctl); + cache->redzone_pad = cache->bufctl_dist - cache->obj_size; + buf_size += sizeof(union kmem_bufctl) + sizeof(struct kmem_buftag); + buf_size = P2ROUND(buf_size, align); + cache->buf_size = buf_size; + } + + kmem_cache_compute_properties(cache, flags); + +#if SLAB_USE_CPU_POOLS + for (cpu_pool_type = kmem_cpu_pool_types; + buf_size <= cpu_pool_type->buf_size; + cpu_pool_type++); + + cache->cpu_pool_type = cpu_pool_type; + + for (i = 0; i < ARRAY_SIZE(cache->cpu_pools); i++) + kmem_cpu_pool_init(&cache->cpu_pools[i], cache); +#endif /* SLAB_USE_CPU_POOLS */ + + simple_lock(&kmem_cache_list_lock); + list_insert_tail(&kmem_cache_list, &cache->node); + kmem_nr_caches++; + simple_unlock(&kmem_cache_list_lock); +} + +static inline int kmem_cache_empty(struct kmem_cache *cache) +{ + return cache->nr_objs == cache->nr_bufs; +} + +static int kmem_cache_grow(struct kmem_cache *cache) +{ + struct kmem_slab *slab; + size_t color; + int empty; + + simple_lock(&cache->lock); + + if (!kmem_cache_empty(cache)) { + simple_unlock(&cache->lock); + return 1; + } + + color = cache->color; + cache->color += cache->align; + + if (cache->color > cache->color_max) + cache->color = 0; + + simple_unlock(&cache->lock); + + slab = kmem_slab_create(cache, color); + + simple_lock(&cache->lock); + + if (slab != NULL) { + list_insert_head(&cache->free_slabs, &slab->list_node); + cache->nr_bufs += cache->bufs_per_slab; + cache->nr_slabs++; + cache->nr_free_slabs++; + } + + /* + * Even if our slab creation failed, another thread might have succeeded + * in growing the cache. + */ + empty = kmem_cache_empty(cache); + + simple_unlock(&cache->lock); + + return !empty; +} + +static void kmem_cache_reap(struct kmem_cache *cache, struct list *dead_slabs) +{ + simple_lock(&cache->lock); + + list_concat(dead_slabs, &cache->free_slabs); + list_init(&cache->free_slabs); + cache->nr_bufs -= cache->bufs_per_slab * cache->nr_free_slabs; + cache->nr_slabs -= cache->nr_free_slabs; + cache->nr_free_slabs = 0; + + simple_unlock(&cache->lock); +} + +/* + * Allocate a raw (unconstructed) buffer from the slab layer of a cache. + * + * The cache must be locked before calling this function. + */ +static void * kmem_cache_alloc_from_slab(struct kmem_cache *cache) +{ + struct kmem_slab *slab; + union kmem_bufctl *bufctl; + + if (!list_empty(&cache->partial_slabs)) + slab = list_first_entry(&cache->partial_slabs, struct kmem_slab, + list_node); + else if (!list_empty(&cache->free_slabs)) + slab = list_first_entry(&cache->free_slabs, struct kmem_slab, + list_node); + else + return NULL; + + bufctl = slab->first_free; + assert(bufctl != NULL); + slab->first_free = bufctl->next; + slab->nr_refs++; + cache->nr_objs++; + + if (slab->nr_refs == cache->bufs_per_slab) { + /* The slab has become complete */ + list_remove(&slab->list_node); + + if (slab->nr_refs == 1) + cache->nr_free_slabs--; + } else if (slab->nr_refs == 1) { + /* + * The slab has become partial. Insert the new slab at the end of + * the list to reduce fragmentation. + */ + list_remove(&slab->list_node); + list_insert_tail(&cache->partial_slabs, &slab->list_node); + cache->nr_free_slabs--; + } + + if ((slab->nr_refs == 1) && (cache->flags & KMEM_CF_USE_TREE)) + rbtree_insert(&cache->active_slabs, &slab->tree_node, + kmem_slab_cmp_insert); + + return kmem_bufctl_to_buf(bufctl, cache); +} + +/* + * Release a buffer to the slab layer of a cache. + * + * The cache must be locked before calling this function. + */ +static void kmem_cache_free_to_slab(struct kmem_cache *cache, void *buf) +{ + struct kmem_slab *slab; + union kmem_bufctl *bufctl; + + if (cache->flags & KMEM_CF_DIRECT) { + assert(cache->slab_size == PAGE_SIZE); + slab = (struct kmem_slab *)P2END((unsigned long)buf, cache->slab_size) + - 1; + } else if (cache->flags & KMEM_CF_USE_PAGE) { + struct vm_page *page; + + page = vm_page_lookup_pa(kvtophys((vm_offset_t)buf)); + assert(page != NULL); + slab = vm_page_get_priv(page); + } else { + struct rbtree_node *node; + + assert(cache->flags & KMEM_CF_USE_TREE); + node = rbtree_lookup_nearest(&cache->active_slabs, buf, + kmem_slab_cmp_lookup, RBTREE_LEFT); + assert(node != NULL); + slab = rbtree_entry(node, struct kmem_slab, tree_node); + } + + assert((unsigned long)buf >= (unsigned long)slab->addr); + assert(((unsigned long)buf + cache->buf_size) + <= vm_page_trunc((unsigned long)slab->addr + cache->slab_size)); + + assert(slab->nr_refs >= 1); + assert(slab->nr_refs <= cache->bufs_per_slab); + bufctl = kmem_buf_to_bufctl(buf, cache); + bufctl->next = slab->first_free; + slab->first_free = bufctl; + slab->nr_refs--; + cache->nr_objs--; + + if (slab->nr_refs == 0) { + /* The slab has become free */ + + if (cache->flags & KMEM_CF_USE_TREE) + rbtree_remove(&cache->active_slabs, &slab->tree_node); + + if (cache->bufs_per_slab > 1) + list_remove(&slab->list_node); + + list_insert_head(&cache->free_slabs, &slab->list_node); + cache->nr_free_slabs++; + } else if (slab->nr_refs == (cache->bufs_per_slab - 1)) { + /* The slab has become partial */ + list_insert_head(&cache->partial_slabs, &slab->list_node); + } +} + +static void kmem_cache_alloc_verify(struct kmem_cache *cache, void *buf, + int construct) +{ + struct kmem_buftag *buftag; + union kmem_bufctl *bufctl; + void *addr; + + buftag = kmem_buf_to_buftag(buf, cache); + + if (buftag->state != KMEM_BUFTAG_FREE) + kmem_cache_error(cache, buf, KMEM_ERR_BUFTAG, buftag); + + addr = kmem_buf_verify_fill(buf, KMEM_FREE_PATTERN, KMEM_UNINIT_PATTERN, + cache->bufctl_dist); + + if (addr != NULL) + kmem_cache_error(cache, buf, KMEM_ERR_MODIFIED, addr); + + addr = buf + cache->obj_size; + memset(addr, KMEM_REDZONE_BYTE, cache->redzone_pad); + + bufctl = kmem_buf_to_bufctl(buf, cache); + bufctl->redzone = KMEM_REDZONE_WORD; + buftag->state = KMEM_BUFTAG_ALLOC; + + if (construct && (cache->ctor != NULL)) + cache->ctor(buf); +} + +vm_offset_t kmem_cache_alloc(struct kmem_cache *cache) +{ + int filled; + void *buf; + +#if SLAB_USE_CPU_POOLS + struct kmem_cpu_pool *cpu_pool; + + cpu_pool = kmem_cpu_pool_get(cache); + + if (cpu_pool->flags & KMEM_CF_NO_CPU_POOL) + goto slab_alloc; + + simple_lock(&cpu_pool->lock); + +fast_alloc: + if (likely(cpu_pool->nr_objs > 0)) { + buf = kmem_cpu_pool_pop(cpu_pool); + simple_unlock(&cpu_pool->lock); + + if (cpu_pool->flags & KMEM_CF_VERIFY) + kmem_cache_alloc_verify(cache, buf, KMEM_AV_CONSTRUCT); + + return (vm_offset_t)buf; + } + + if (cpu_pool->array != NULL) { + filled = kmem_cpu_pool_fill(cpu_pool, cache); + + if (!filled) { + simple_unlock(&cpu_pool->lock); + + filled = kmem_cache_grow(cache); + + if (!filled) + return 0; + + simple_lock(&cpu_pool->lock); + } + + goto fast_alloc; + } + + simple_unlock(&cpu_pool->lock); +#endif /* SLAB_USE_CPU_POOLS */ + +slab_alloc: + simple_lock(&cache->lock); + buf = kmem_cache_alloc_from_slab(cache); + simple_unlock(&cache->lock); + + if (buf == NULL) { + filled = kmem_cache_grow(cache); + + if (!filled) + return 0; + + goto slab_alloc; + } + + if (cache->flags & KMEM_CF_VERIFY) + kmem_cache_alloc_verify(cache, buf, KMEM_AV_NOCONSTRUCT); + + if (cache->ctor != NULL) + cache->ctor(buf); + + return (vm_offset_t)buf; +} + +static void kmem_cache_free_verify(struct kmem_cache *cache, void *buf) +{ + struct rbtree_node *node; + struct kmem_buftag *buftag; + struct kmem_slab *slab; + union kmem_bufctl *bufctl; + unsigned char *redzone_byte; + unsigned long slabend; + + assert(cache->flags & KMEM_CF_USE_TREE); + + simple_lock(&cache->lock); + node = rbtree_lookup_nearest(&cache->active_slabs, buf, + kmem_slab_cmp_lookup, RBTREE_LEFT); + simple_unlock(&cache->lock); + + if (node == NULL) + kmem_cache_error(cache, buf, KMEM_ERR_INVALID, NULL); + + slab = rbtree_entry(node, struct kmem_slab, tree_node); + slabend = P2ALIGN((unsigned long)slab->addr + cache->slab_size, PAGE_SIZE); + + if ((unsigned long)buf >= slabend) + kmem_cache_error(cache, buf, KMEM_ERR_INVALID, NULL); + + if ((((unsigned long)buf - (unsigned long)slab->addr) % cache->buf_size) + != 0) + kmem_cache_error(cache, buf, KMEM_ERR_INVALID, NULL); + + /* + * As the buffer address is valid, accessing its buftag is safe. + */ + buftag = kmem_buf_to_buftag(buf, cache); + + if (buftag->state != KMEM_BUFTAG_ALLOC) { + if (buftag->state == KMEM_BUFTAG_FREE) + kmem_cache_error(cache, buf, KMEM_ERR_DOUBLEFREE, NULL); + else + kmem_cache_error(cache, buf, KMEM_ERR_BUFTAG, buftag); + } + + redzone_byte = buf + cache->obj_size; + bufctl = kmem_buf_to_bufctl(buf, cache); + + while (redzone_byte < (unsigned char *)bufctl) { + if (*redzone_byte != KMEM_REDZONE_BYTE) + kmem_cache_error(cache, buf, KMEM_ERR_REDZONE, redzone_byte); + + redzone_byte++; + } + + if (bufctl->redzone != KMEM_REDZONE_WORD) { + unsigned long word; + + word = KMEM_REDZONE_WORD; + redzone_byte = kmem_buf_verify_bytes(&bufctl->redzone, &word, + sizeof(bufctl->redzone)); + kmem_cache_error(cache, buf, KMEM_ERR_REDZONE, redzone_byte); + } + + kmem_buf_fill(buf, KMEM_FREE_PATTERN, cache->bufctl_dist); + buftag->state = KMEM_BUFTAG_FREE; +} + +void kmem_cache_free(struct kmem_cache *cache, vm_offset_t obj) +{ +#if SLAB_USE_CPU_POOLS + struct kmem_cpu_pool *cpu_pool; + void **array; + + cpu_pool = kmem_cpu_pool_get(cache); + + if (cpu_pool->flags & KMEM_CF_VERIFY) { +#else /* SLAB_USE_CPU_POOLS */ + if (cache->flags & KMEM_CF_VERIFY) { +#endif /* SLAB_USE_CPU_POOLS */ + kmem_cache_free_verify(cache, (void *)obj); + } + +#if SLAB_USE_CPU_POOLS + if (cpu_pool->flags & KMEM_CF_NO_CPU_POOL) + goto slab_free; + + simple_lock(&cpu_pool->lock); + +fast_free: + if (likely(cpu_pool->nr_objs < cpu_pool->size)) { + kmem_cpu_pool_push(cpu_pool, (void *)obj); + simple_unlock(&cpu_pool->lock); + return; + } + + if (cpu_pool->array != NULL) { + kmem_cpu_pool_drain(cpu_pool, cache); + goto fast_free; + } + + simple_unlock(&cpu_pool->lock); + + array = (void *)kmem_cache_alloc(cache->cpu_pool_type->array_cache); + + if (array != NULL) { + simple_lock(&cpu_pool->lock); + + /* + * Another thread may have built the CPU pool while the lock was + * dropped. + */ + if (cpu_pool->array != NULL) { + simple_unlock(&cpu_pool->lock); + kmem_cache_free(cache->cpu_pool_type->array_cache, + (vm_offset_t)array); + simple_lock(&cpu_pool->lock); + goto fast_free; + } + + kmem_cpu_pool_build(cpu_pool, cache, array); + goto fast_free; + } + +slab_free: +#endif /* SLAB_USE_CPU_POOLS */ + + simple_lock(&cache->lock); + kmem_cache_free_to_slab(cache, (void *)obj); + simple_unlock(&cache->lock); +} + +void slab_collect(void) +{ + struct kmem_cache *cache; + struct kmem_slab *slab; + struct list dead_slabs; + + if (elapsed_ticks <= (kmem_gc_last_tick + KMEM_GC_INTERVAL)) + return; + + kmem_gc_last_tick = elapsed_ticks; + + list_init(&dead_slabs); + + simple_lock(&kmem_cache_list_lock); + + list_for_each_entry(&kmem_cache_list, cache, node) + kmem_cache_reap(cache, &dead_slabs); + + simple_unlock(&kmem_cache_list_lock); + + while (!list_empty(&dead_slabs)) { + slab = list_first_entry(&dead_slabs, struct kmem_slab, list_node); + list_remove(&slab->list_node); + kmem_slab_destroy(slab, slab->cache); + } +} + +void slab_bootstrap(void) +{ + /* Make sure a bufctl can always be stored in a buffer */ + assert(sizeof(union kmem_bufctl) <= KMEM_ALIGN_MIN); + + list_init(&kmem_cache_list); + simple_lock_init(&kmem_cache_list_lock); +} + +void slab_init(void) +{ +#if SLAB_USE_CPU_POOLS + struct kmem_cpu_pool_type *cpu_pool_type; + char name[KMEM_CACHE_NAME_SIZE]; + size_t i, size; +#endif /* SLAB_USE_CPU_POOLS */ + +#if SLAB_USE_CPU_POOLS + for (i = 0; i < ARRAY_SIZE(kmem_cpu_pool_types); i++) { + cpu_pool_type = &kmem_cpu_pool_types[i]; + cpu_pool_type->array_cache = &kmem_cpu_array_caches[i]; + sprintf(name, "kmem_cpu_array_%d", cpu_pool_type->array_size); + size = sizeof(void *) * cpu_pool_type->array_size; + kmem_cache_init(cpu_pool_type->array_cache, name, size, + cpu_pool_type->array_align, NULL, 0); + } +#endif /* SLAB_USE_CPU_POOLS */ + + /* + * Prevent off slab data for the slab cache to avoid infinite recursion. + */ + kmem_cache_init(&kmem_slab_cache, "kmem_slab", sizeof(struct kmem_slab), + 0, NULL, KMEM_CACHE_NOOFFSLAB); +} + +void kalloc_init(void) +{ + char name[KMEM_CACHE_NAME_SIZE]; + size_t i, size; + + size = 1 << KALLOC_FIRST_SHIFT; + + for (i = 0; i < ARRAY_SIZE(kalloc_caches); i++) { + sprintf(name, "kalloc_%lu", size); + kmem_cache_init(&kalloc_caches[i], name, size, 0, NULL, 0); + size <<= 1; + } +} + +/* + * Return the kalloc cache index matching the given allocation size, which + * must be strictly greater than 0. + */ +static inline size_t kalloc_get_index(unsigned long size) +{ + assert(size != 0); + + size = (size - 1) >> KALLOC_FIRST_SHIFT; + + if (size == 0) + return 0; + else + return (sizeof(long) * 8) - __builtin_clzl(size); +} + +static void kalloc_verify(struct kmem_cache *cache, void *buf, size_t size) +{ + size_t redzone_size; + void *redzone; + + assert(size <= cache->obj_size); + + redzone = buf + size; + redzone_size = cache->obj_size - size; + memset(redzone, KMEM_REDZONE_BYTE, redzone_size); +} + +vm_offset_t kalloc(vm_size_t size) +{ + size_t index; + void *buf; + + if (size == 0) + return 0; + + index = kalloc_get_index(size); + + if (index < ARRAY_SIZE(kalloc_caches)) { + struct kmem_cache *cache; + + cache = &kalloc_caches[index]; + buf = (void *)kmem_cache_alloc(cache); + + if ((buf != 0) && (cache->flags & KMEM_CF_VERIFY)) + kalloc_verify(cache, buf, size); + } else if (size <= PAGE_SIZE) { + buf = (void *)kmem_pagealloc_physmem(PAGE_SIZE); + } else { + buf = (void *)kmem_pagealloc_virtual(size, 0); + } + + return (vm_offset_t)buf; +} + +static void kfree_verify(struct kmem_cache *cache, void *buf, size_t size) +{ + unsigned char *redzone_byte, *redzone_end; + + assert(size <= cache->obj_size); + + redzone_byte = buf + size; + redzone_end = buf + cache->obj_size; + + while (redzone_byte < redzone_end) { + if (*redzone_byte != KMEM_REDZONE_BYTE) + kmem_cache_error(cache, buf, KMEM_ERR_REDZONE, redzone_byte); + + redzone_byte++; + } +} + +void kfree(vm_offset_t data, vm_size_t size) +{ + size_t index; + + if ((data == 0) || (size == 0)) + return; + + index = kalloc_get_index(size); + + if (index < ARRAY_SIZE(kalloc_caches)) { + struct kmem_cache *cache; + + cache = &kalloc_caches[index]; + + if (cache->flags & KMEM_CF_VERIFY) + kfree_verify(cache, (void *)data, size); + + kmem_cache_free(cache, data); + } else if (size <= PAGE_SIZE) { + kmem_pagefree_physmem(data, PAGE_SIZE); + } else { + kmem_pagefree_virtual(data, size); + } +} + +static void _slab_info(int (printx)(const char *fmt, ...)) +{ + struct kmem_cache *cache; + vm_size_t mem_usage, mem_reclaimable, mem_total, mem_total_reclaimable; + + mem_total = 0; + mem_total_reclaimable = 0; + + printx("cache obj slab bufs objs bufs" + " total reclaimable\n" + "name flags size size /slab usage count" + " memory memory\n"); + + simple_lock(&kmem_cache_list_lock); + + list_for_each_entry(&kmem_cache_list, cache, node) { + simple_lock(&cache->lock); + + mem_usage = (cache->nr_slabs * cache->slab_size) >> 10; + mem_reclaimable = (cache->nr_free_slabs * cache->slab_size) >> 10; + + printx("%-20s %04x %7lu %3luk %4lu %6lu %6lu %7uk %10uk\n", + cache->name, cache->flags, cache->obj_size, + cache->slab_size >> 10, + cache->bufs_per_slab, cache->nr_objs, cache->nr_bufs, + mem_usage, mem_reclaimable); + + simple_unlock(&cache->lock); + + mem_total += mem_usage; + mem_total_reclaimable += mem_reclaimable; + } + + simple_unlock(&kmem_cache_list_lock); + + printx("total: %uk, reclaimable: %uk\n", + mem_total, mem_total_reclaimable); +} + +void slab_info(void) +{ + _slab_info(printf); +} + +#if MACH_KDB +#include <ddb/db_output.h> + +void db_show_slab_info(void) +{ + _slab_info(db_printf); +} + +void db_whatis_slab(vm_offset_t a) +{ + struct kmem_cache *cache; + int done = 0; + +#ifndef SLAB_VERIFY + db_printf("enabling SLAB_VERIFY is recommended\n"); +#endif + + simple_lock(&kmem_cache_list_lock); + + list_for_each_entry(&kmem_cache_list, cache, node) { + if (a >= (vm_offset_t) cache + && a < (vm_offset_t) cache + sizeof(*cache)) + db_printf("Cache %s\n", cache->name); + + simple_lock(&cache->lock); + + if (cache->flags & KMEM_CF_USE_TREE) { + struct rbtree_node *node; + + node = rbtree_lookup_nearest(&cache->active_slabs, (void*) a, + kmem_slab_cmp_lookup, RBTREE_LEFT); + if (node) { + struct kmem_slab *slab; + slab = rbtree_entry(node, struct kmem_slab, tree_node); + if (a >= (vm_offset_t) slab->addr + && a < (vm_offset_t) slab->addr + cache->slab_size) { + db_printf("Allocated from cache %s\n", cache->name); + done = 1; + goto out_cache; + } + } + } + + union kmem_bufctl *free; + struct kmem_slab *slab; + + list_for_each_entry(&cache->partial_slabs, slab, list_node) { + if (a >= (vm_offset_t) slab->addr + && a < (vm_offset_t) slab->addr + cache->slab_size) { + db_printf("In cache %s\n", cache->name); + + for (free = slab->first_free; free; free = free->next) { + void *buf = kmem_bufctl_to_buf(free, cache); + + if (a >= (vm_offset_t) buf + && a < (vm_offset_t) buf + cache->buf_size) { + db_printf(" In free list\n"); + break; + } + } + + done = 1; + goto out_cache; + } + } + + list_for_each_entry(&cache->free_slabs, slab, list_node) { + if (a >= (vm_offset_t) slab->addr + && a < (vm_offset_t) slab->addr + cache->slab_size) { + db_printf("In cache %s\n", cache->name); + + for (free = slab->first_free; free; free = free->next) { + void *buf = kmem_bufctl_to_buf(free, cache); + + if (a >= (vm_offset_t) buf + && a < (vm_offset_t) buf + cache->buf_size) { + db_printf(" In free list\n"); + break; + } + } + + done = 1; + goto out_cache; + } + } + +out_cache: + simple_unlock(&cache->lock); + if (done) + goto out; + } + +out: + simple_unlock(&kmem_cache_list_lock); +} + +#endif /* MACH_KDB */ + +#if MACH_DEBUG +kern_return_t host_slab_info(host_t host, cache_info_array_t *infop, + unsigned int *infoCntp) +{ + struct kmem_cache *cache; + cache_info_t *info; + unsigned int i, nr_caches; + vm_size_t info_size; + kern_return_t kr; + + if (host == HOST_NULL) + return KERN_INVALID_HOST; + + /* Assume the cache list is mostly unaltered once the kernel is ready */ + +retry: + /* Harmless unsynchronized access, real value checked later */ + nr_caches = kmem_nr_caches; + info_size = nr_caches * sizeof(*info); + info = (cache_info_t *)kalloc(info_size); + + if (info == NULL) + return KERN_RESOURCE_SHORTAGE; + + i = 0; + + simple_lock(&kmem_cache_list_lock); + + if (nr_caches != kmem_nr_caches) { + simple_unlock(&kmem_cache_list_lock); + kfree((vm_offset_t)info, info_size); + goto retry; + } + + list_for_each_entry(&kmem_cache_list, cache, node) { + simple_lock(&cache->lock); + info[i].flags = cache->flags; +#if SLAB_USE_CPU_POOLS + info[i].cpu_pool_size = cache->cpu_pool_type->array_size; +#else /* SLAB_USE_CPU_POOLS */ + info[i].cpu_pool_size = 0; +#endif /* SLAB_USE_CPU_POOLS */ + info[i].obj_size = cache->obj_size; + info[i].align = cache->align; + info[i].buf_size = cache->buf_size; + info[i].slab_size = cache->slab_size; + info[i].bufs_per_slab = cache->bufs_per_slab; + info[i].nr_objs = cache->nr_objs; + info[i].nr_bufs = cache->nr_bufs; + info[i].nr_slabs = cache->nr_slabs; + info[i].nr_free_slabs = cache->nr_free_slabs; + strncpy(info[i].name, cache->name, sizeof(info[i].name)); + info[i].name[sizeof(info[i].name) - 1] = '\0'; + simple_unlock(&cache->lock); + + i++; + } + + simple_unlock(&kmem_cache_list_lock); + + if (nr_caches <= *infoCntp) { + memcpy(*infop, info, info_size); + } else { + vm_offset_t info_addr; + vm_size_t total_size; + vm_map_copy_t copy; + + kr = kmem_alloc_pageable(ipc_kernel_map, &info_addr, info_size); + + if (kr != KERN_SUCCESS) + goto out; + + memcpy((char *)info_addr, info, info_size); + total_size = round_page(info_size); + + if (info_size < total_size) + memset((char *)(info_addr + info_size), + 0, total_size - info_size); + + kr = vm_map_copyin(ipc_kernel_map, info_addr, info_size, TRUE, ©); + assert(kr == KERN_SUCCESS); + *infop = (cache_info_t *)copy; + } + + *infoCntp = nr_caches; + kr = KERN_SUCCESS; + +out: + kfree((vm_offset_t)info, info_size); + + return kr; +} +#endif /* MACH_DEBUG */ |