1 // SPDX-License-Identifier: GPL-2.0
2 #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
15 int nr_allocated;
16 int preempt_count;
17 int test_verbose;
18
19 struct 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 };
30
31 void kmem_cache_set_non_kernel(struct kmem_cache *cachep, unsigned int val)
32 {
33 cachep->non_kernel = val;
34 }
35
36 unsigned long kmem_cache_get_alloc(struct kmem_cache *cachep)
37 {
38 return cachep->size * cachep->nr_allocated;
39 }
40
41 unsigned long kmem_cache_nr_allocated(struct kmem_cache *cachep)
42 {
43 return cachep->nr_allocated;
44 }
45
46 unsigned long kmem_cache_nr_tallocated(struct kmem_cache *cachep)
47 {
48 return cachep->nr_tallocated;
49 }
50
51 void kmem_cache_zero_nr_tallocated(struct kmem_cache *cachep)
52 {
53 cachep->nr_tallocated = 0;
54 }
55
56 void *kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru,
57 int gfp)
58 {
59 void *p;
60
61 if (!(gfp & __GFP_DIRECT_RECLAIM)) {
62 if (!cachep->non_kernel)
63 return NULL;
64
65 cachep->non_kernel--;
66 }
67
68 pthread_mutex_lock(&cachep->lock);
69 if (cachep->nr_objs) {
70 struct radix_tree_node *node = cachep->objs;
71 cachep->nr_objs--;
72 cachep->objs = node->parent;
73 pthread_mutex_unlock(&cachep->lock);
74 node->parent = NULL;
75 p = node;
76 } else {
77 pthread_mutex_unlock(&cachep->lock);
78 if (cachep->align)
79 posix_memalign(&p, cachep->align, cachep->size);
80 else
81 p = malloc(cachep->size);
82 if (cachep->ctor)
83 cachep->ctor(p);
84 else if (gfp & __GFP_ZERO)
85 memset(p, 0, cachep->size);
86 }
87
88 uatomic_inc(&cachep->nr_allocated);
89 uatomic_inc(&nr_allocated);
90 uatomic_inc(&cachep->nr_tallocated);
91 if (kmalloc_verbose)
92 printf("Allocating %p from slab\n", p);
93 return p;
94 }
95
96 void __kmem_cache_free_locked(struct kmem_cache *cachep, void *objp)
97 {
98 assert(objp);
99 if (cachep->nr_objs > 10 || cachep->align) {
100 memset(objp, POISON_FREE, cachep->size);
101 free(objp);
102 } else {
103 struct radix_tree_node *node = objp;
104 cachep->nr_objs++;
105 node->parent = cachep->objs;
106 cachep->objs = node;
107 }
108 }
109
110 void kmem_cache_free_locked(struct kmem_cache *cachep, void *objp)
111 {
112 uatomic_dec(&nr_allocated);
113 uatomic_dec(&cachep->nr_allocated);
114 if (kmalloc_verbose)
115 printf("Freeing %p to slab\n", objp);
116 __kmem_cache_free_locked(cachep, objp);
117 }
118
119 void kmem_cache_free(struct kmem_cache *cachep, void *objp)
120 {
121 pthread_mutex_lock(&cachep->lock);
122 kmem_cache_free_locked(cachep, objp);
123 pthread_mutex_unlock(&cachep->lock);
124 }
125
126 void kmem_cache_free_bulk(struct kmem_cache *cachep, size_t size, void **list)
127 {
128 if (kmalloc_verbose)
129 pr_debug("Bulk free %p[0-%lu]\n", list, size - 1);
130
131 pthread_mutex_lock(&cachep->lock);
132 for (int i = 0; i < size; i++)
133 kmem_cache_free_locked(cachep, list[i]);
134 pthread_mutex_unlock(&cachep->lock);
135 }
136
137 void kmem_cache_shrink(struct kmem_cache *cachep)
138 {
139 }
140
141 int kmem_cache_alloc_bulk(struct kmem_cache *cachep, gfp_t gfp, size_t size,
142 void **p)
143 {
144 size_t i;
145
146 if (kmalloc_verbose)
147 pr_debug("Bulk alloc %lu\n", size);
148
149 pthread_mutex_lock(&cachep->lock);
150 if (cachep->nr_objs >= size) {
151 struct radix_tree_node *node;
152
153 for (i = 0; i < size; i++) {
154 if (!(gfp & __GFP_DIRECT_RECLAIM)) {
155 if (!cachep->non_kernel)
156 break;
157 cachep->non_kernel--;
158 }
159
160 node = cachep->objs;
161 cachep->nr_objs--;
162 cachep->objs = node->parent;
163 p[i] = node;
164 node->parent = NULL;
165 }
166 pthread_mutex_unlock(&cachep->lock);
167 } else {
168 pthread_mutex_unlock(&cachep->lock);
169 for (i = 0; i < size; i++) {
170 if (!(gfp & __GFP_DIRECT_RECLAIM)) {
171 if (!cachep->non_kernel)
172 break;
173 cachep->non_kernel--;
174 }
175
176 if (cachep->align) {
177 posix_memalign(&p[i], cachep->align,
178 cachep->size);
179 } else {
180 p[i] = malloc(cachep->size);
181 if (!p[i])
182 break;
183 }
184 if (cachep->ctor)
185 cachep->ctor(p[i]);
186 else if (gfp & __GFP_ZERO)
187 memset(p[i], 0, cachep->size);
188 }
189 }
190
191 if (i < size) {
192 size = i;
193 pthread_mutex_lock(&cachep->lock);
194 for (i = 0; i < size; i++)
195 __kmem_cache_free_locked(cachep, p[i]);
196 pthread_mutex_unlock(&cachep->lock);
197 return 0;
198 }
199
200 for (i = 0; i < size; i++) {
201 uatomic_inc(&nr_allocated);
202 uatomic_inc(&cachep->nr_allocated);
203 uatomic_inc(&cachep->nr_tallocated);
204 if (kmalloc_verbose)
205 printf("Allocating %p from slab\n", p[i]);
206 }
207
208 return size;
209 }
210
211 struct kmem_cache *
212 kmem_cache_create(const char *name, unsigned int size, unsigned int align,
213 unsigned int flags, void (*ctor)(void *))
214 {
215 struct kmem_cache *ret = malloc(sizeof(*ret));
216
217 pthread_mutex_init(&ret->lock, NULL);
218 ret->size = size;
219 ret->align = align;
220 ret->nr_objs = 0;
221 ret->nr_allocated = 0;
222 ret->nr_tallocated = 0;
223 ret->objs = NULL;
224 ret->ctor = ctor;
225 ret->non_kernel = 0;
226 return ret;
227 }
228
229 /*
230 * Test the test infrastructure for kem_cache_alloc/free and bulk counterparts.
231 */
232 void test_kmem_cache_bulk(void)
233 {
234 int i;
235 void *list[12];
236 static struct kmem_cache *test_cache, *test_cache2;
237
238 /*
239 * Testing the bulk allocators without aligned kmem_cache to force the
240 * bulk alloc/free to reuse
241 */
242 test_cache = kmem_cache_create("test_cache", 256, 0, SLAB_PANIC, NULL);
243
244 for (i = 0; i < 5; i++)
245 list[i] = kmem_cache_alloc(test_cache, __GFP_DIRECT_RECLAIM);
246
247 for (i = 0; i < 5; i++)
248 kmem_cache_free(test_cache, list[i]);
249 assert(test_cache->nr_objs == 5);
250
251 kmem_cache_alloc_bulk(test_cache, __GFP_DIRECT_RECLAIM, 5, list);
252 kmem_cache_free_bulk(test_cache, 5, list);
253
254 for (i = 0; i < 12 ; i++)
255 list[i] = kmem_cache_alloc(test_cache, __GFP_DIRECT_RECLAIM);
256
257 for (i = 0; i < 12; i++)
258 kmem_cache_free(test_cache, list[i]);
259
260 /* The last free will not be kept around */
261 assert(test_cache->nr_objs == 11);
262
263 /* Aligned caches will immediately free */
264 test_cache2 = kmem_cache_create("test_cache2", 128, 128, SLAB_PANIC, NULL);
265
266 kmem_cache_alloc_bulk(test_cache2, __GFP_DIRECT_RECLAIM, 10, list);
267 kmem_cache_free_bulk(test_cache2, 10, list);
268 assert(!test_cache2->nr_objs);
269
270
271 }
272
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