296 lines · c
1// SPDX-License-Identifier: GPL-2.02#include <stdlib.h>3#include <string.h>4#include <malloc.h>5#include <pthread.h>6#include <unistd.h>7#include <assert.h>8 9#include <linux/gfp.h>10#include <linux/poison.h>11#include <linux/slab.h>12#include <linux/radix-tree.h>13#include <urcu/uatomic.h>14 15int nr_allocated;16int preempt_count;17int test_verbose;18 19struct kmem_cache {20 pthread_mutex_t lock;21 unsigned int size;22 unsigned int align;23 int nr_objs;24 void *objs;25 void (*ctor)(void *);26 unsigned int non_kernel;27 unsigned long nr_allocated;28 unsigned long nr_tallocated;29 bool exec_callback;30 void (*callback)(void *);31 void *private;32};33 34void kmem_cache_set_callback(struct kmem_cache *cachep, void (*callback)(void *))35{36 cachep->callback = callback;37}38 39void kmem_cache_set_private(struct kmem_cache *cachep, void *private)40{41 cachep->private = private;42}43 44void kmem_cache_set_non_kernel(struct kmem_cache *cachep, unsigned int val)45{46 cachep->non_kernel = val;47}48 49unsigned long kmem_cache_get_alloc(struct kmem_cache *cachep)50{51 return cachep->size * cachep->nr_allocated;52}53 54unsigned long kmem_cache_nr_allocated(struct kmem_cache *cachep)55{56 return cachep->nr_allocated;57}58 59unsigned long kmem_cache_nr_tallocated(struct kmem_cache *cachep)60{61 return cachep->nr_tallocated;62}63 64void kmem_cache_zero_nr_tallocated(struct kmem_cache *cachep)65{66 cachep->nr_tallocated = 0;67}68 69void *kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru,70 int gfp)71{72 void *p;73 74 if (cachep->exec_callback) {75 if (cachep->callback)76 cachep->callback(cachep->private);77 cachep->exec_callback = false;78 }79 80 if (!(gfp & __GFP_DIRECT_RECLAIM)) {81 if (!cachep->non_kernel) {82 cachep->exec_callback = true;83 return NULL;84 }85 86 cachep->non_kernel--;87 }88 89 pthread_mutex_lock(&cachep->lock);90 if (cachep->nr_objs) {91 struct radix_tree_node *node = cachep->objs;92 cachep->nr_objs--;93 cachep->objs = node->parent;94 pthread_mutex_unlock(&cachep->lock);95 node->parent = NULL;96 p = node;97 } else {98 pthread_mutex_unlock(&cachep->lock);99 if (cachep->align)100 posix_memalign(&p, cachep->align, cachep->size);101 else102 p = malloc(cachep->size);103 if (cachep->ctor)104 cachep->ctor(p);105 else if (gfp & __GFP_ZERO)106 memset(p, 0, cachep->size);107 }108 109 uatomic_inc(&cachep->nr_allocated);110 uatomic_inc(&nr_allocated);111 uatomic_inc(&cachep->nr_tallocated);112 if (kmalloc_verbose)113 printf("Allocating %p from slab\n", p);114 return p;115}116 117void __kmem_cache_free_locked(struct kmem_cache *cachep, void *objp)118{119 assert(objp);120 if (cachep->nr_objs > 10 || cachep->align) {121 memset(objp, POISON_FREE, cachep->size);122 free(objp);123 } else {124 struct radix_tree_node *node = objp;125 cachep->nr_objs++;126 node->parent = cachep->objs;127 cachep->objs = node;128 }129}130 131void kmem_cache_free_locked(struct kmem_cache *cachep, void *objp)132{133 uatomic_dec(&nr_allocated);134 uatomic_dec(&cachep->nr_allocated);135 if (kmalloc_verbose)136 printf("Freeing %p to slab\n", objp);137 __kmem_cache_free_locked(cachep, objp);138}139 140void kmem_cache_free(struct kmem_cache *cachep, void *objp)141{142 pthread_mutex_lock(&cachep->lock);143 kmem_cache_free_locked(cachep, objp);144 pthread_mutex_unlock(&cachep->lock);145}146 147void kmem_cache_free_bulk(struct kmem_cache *cachep, size_t size, void **list)148{149 if (kmalloc_verbose)150 pr_debug("Bulk free %p[0-%lu]\n", list, size - 1);151 152 pthread_mutex_lock(&cachep->lock);153 for (int i = 0; i < size; i++)154 kmem_cache_free_locked(cachep, list[i]);155 pthread_mutex_unlock(&cachep->lock);156}157 158void kmem_cache_shrink(struct kmem_cache *cachep)159{160}161 162int kmem_cache_alloc_bulk(struct kmem_cache *cachep, gfp_t gfp, size_t size,163 void **p)164{165 size_t i;166 167 if (kmalloc_verbose)168 pr_debug("Bulk alloc %lu\n", size);169 170 pthread_mutex_lock(&cachep->lock);171 if (cachep->nr_objs >= size) {172 struct radix_tree_node *node;173 174 for (i = 0; i < size; i++) {175 if (!(gfp & __GFP_DIRECT_RECLAIM)) {176 if (!cachep->non_kernel)177 break;178 cachep->non_kernel--;179 }180 181 node = cachep->objs;182 cachep->nr_objs--;183 cachep->objs = node->parent;184 p[i] = node;185 node->parent = NULL;186 }187 pthread_mutex_unlock(&cachep->lock);188 } else {189 pthread_mutex_unlock(&cachep->lock);190 for (i = 0; i < size; i++) {191 if (!(gfp & __GFP_DIRECT_RECLAIM)) {192 if (!cachep->non_kernel)193 break;194 cachep->non_kernel--;195 }196 197 if (cachep->align) {198 posix_memalign(&p[i], cachep->align,199 cachep->size);200 } else {201 p[i] = malloc(cachep->size);202 if (!p[i])203 break;204 }205 if (cachep->ctor)206 cachep->ctor(p[i]);207 else if (gfp & __GFP_ZERO)208 memset(p[i], 0, cachep->size);209 }210 }211 212 if (i < size) {213 size = i;214 pthread_mutex_lock(&cachep->lock);215 for (i = 0; i < size; i++)216 __kmem_cache_free_locked(cachep, p[i]);217 pthread_mutex_unlock(&cachep->lock);218 return 0;219 }220 221 for (i = 0; i < size; i++) {222 uatomic_inc(&nr_allocated);223 uatomic_inc(&cachep->nr_allocated);224 uatomic_inc(&cachep->nr_tallocated);225 if (kmalloc_verbose)226 printf("Allocating %p from slab\n", p[i]);227 }228 229 return size;230}231 232struct kmem_cache *233kmem_cache_create(const char *name, unsigned int size, unsigned int align,234 unsigned int flags, void (*ctor)(void *))235{236 struct kmem_cache *ret = malloc(sizeof(*ret));237 238 pthread_mutex_init(&ret->lock, NULL);239 ret->size = size;240 ret->align = align;241 ret->nr_objs = 0;242 ret->nr_allocated = 0;243 ret->nr_tallocated = 0;244 ret->objs = NULL;245 ret->ctor = ctor;246 ret->non_kernel = 0;247 ret->exec_callback = false;248 ret->callback = NULL;249 ret->private = NULL;250 return ret;251}252 253/*254 * Test the test infrastructure for kem_cache_alloc/free and bulk counterparts.255 */256void test_kmem_cache_bulk(void)257{258 int i;259 void *list[12];260 static struct kmem_cache *test_cache, *test_cache2;261 262 /*263 * Testing the bulk allocators without aligned kmem_cache to force the264 * bulk alloc/free to reuse265 */266 test_cache = kmem_cache_create("test_cache", 256, 0, SLAB_PANIC, NULL);267 268 for (i = 0; i < 5; i++)269 list[i] = kmem_cache_alloc(test_cache, __GFP_DIRECT_RECLAIM);270 271 for (i = 0; i < 5; i++)272 kmem_cache_free(test_cache, list[i]);273 assert(test_cache->nr_objs == 5);274 275 kmem_cache_alloc_bulk(test_cache, __GFP_DIRECT_RECLAIM, 5, list);276 kmem_cache_free_bulk(test_cache, 5, list);277 278 for (i = 0; i < 12 ; i++)279 list[i] = kmem_cache_alloc(test_cache, __GFP_DIRECT_RECLAIM);280 281 for (i = 0; i < 12; i++)282 kmem_cache_free(test_cache, list[i]);283 284 /* The last free will not be kept around */285 assert(test_cache->nr_objs == 11);286 287 /* Aligned caches will immediately free */288 test_cache2 = kmem_cache_create("test_cache2", 128, 128, SLAB_PANIC, NULL);289 290 kmem_cache_alloc_bulk(test_cache2, __GFP_DIRECT_RECLAIM, 10, list);291 kmem_cache_free_bulk(test_cache2, 10, list);292 assert(!test_cache2->nr_objs);293 294 295}296