Commit | Line | Data |
---|---|---|
d24c33a4 JA |
1 | /* |
2 | * simple memory allocator, backed by mmap() so that it hands out memory | |
3 | * that can be shared across processes and threads | |
4 | */ | |
5 | #include <sys/mman.h> | |
6 | #include <stdio.h> | |
7 | #include <stdlib.h> | |
8 | #include <assert.h> | |
9 | #include <string.h> | |
10 | #include <unistd.h> | |
11 | #include <sys/types.h> | |
12 | #include <limits.h> | |
13 | ||
6548f47f | 14 | #include "mutex.h" |
b3268b92 | 15 | #include "arch/arch.h" |
d24c33a4 | 16 | |
55f6491d | 17 | #define SMALLOC_REDZONE /* define to detect memory corruption */ |
d24c33a4 | 18 | |
ec996e9c JA |
19 | #define SMALLOC_BPB 32 /* block size, bytes-per-bit in bitmap */ |
20 | #define SMALLOC_BPI (sizeof(unsigned int) * 8) | |
21 | #define SMALLOC_BPL (SMALLOC_BPB * SMALLOC_BPI) | |
22 | ||
5e012980 | 23 | #define INITIAL_SIZE 8192*1024 /* new pool size */ |
68857686 | 24 | #define MAX_POOLS 128 /* maximum number of pools to setup */ |
d24c33a4 | 25 | |
55f6491d JA |
26 | #define SMALLOC_PRE_RED 0xdeadbeefU |
27 | #define SMALLOC_POST_RED 0x5aa55aa5U | |
55f6491d | 28 | |
2b386d25 | 29 | unsigned int smalloc_pool_size = INITIAL_SIZE; |
122426da | 30 | const int int_mask = sizeof(int) - 1; |
2b386d25 | 31 | |
d24c33a4 | 32 | struct pool { |
6548f47f | 33 | struct fio_mutex *lock; /* protects this pool */ |
d24c33a4 | 34 | void *map; /* map of blocks */ |
ec996e9c JA |
35 | unsigned int *bitmap; /* blocks free/busy map */ |
36 | unsigned int free_blocks; /* free blocks */ | |
37 | unsigned int nr_blocks; /* total blocks */ | |
38 | unsigned int next_non_full; | |
d24c33a4 | 39 | int fd; /* memory backing fd */ |
ec996e9c JA |
40 | unsigned int mmap_size; |
41 | }; | |
42 | ||
43 | struct block_hdr { | |
44 | unsigned int size; | |
45 | #ifdef SMALLOC_REDZONE | |
46 | unsigned int prered; | |
47 | #endif | |
d24c33a4 JA |
48 | }; |
49 | ||
50 | static struct pool mp[MAX_POOLS]; | |
51 | static unsigned int nr_pools; | |
52 | static unsigned int last_pool; | |
6548f47f | 53 | static struct fio_mutex *lock; |
d24c33a4 | 54 | |
d24c33a4 JA |
55 | static inline void pool_lock(struct pool *pool) |
56 | { | |
2e3e31e3 | 57 | fio_mutex_down(pool->lock); |
d24c33a4 JA |
58 | } |
59 | ||
60 | static inline void pool_unlock(struct pool *pool) | |
61 | { | |
2e3e31e3 | 62 | fio_mutex_up(pool->lock); |
d24c33a4 JA |
63 | } |
64 | ||
65864cf7 | 65 | static inline void global_read_lock(void) |
d24c33a4 | 66 | { |
2e3e31e3 | 67 | fio_mutex_down_read(lock); |
d24c33a4 JA |
68 | } |
69 | ||
65864cf7 | 70 | static inline void global_read_unlock(void) |
d24c33a4 | 71 | { |
2e3e31e3 | 72 | fio_mutex_up_read(lock); |
65864cf7 JA |
73 | } |
74 | ||
75 | static inline void global_write_lock(void) | |
76 | { | |
2e3e31e3 | 77 | fio_mutex_down_write(lock); |
65864cf7 JA |
78 | } |
79 | ||
80 | static inline void global_write_unlock(void) | |
81 | { | |
2e3e31e3 | 82 | fio_mutex_up_write(lock); |
d24c33a4 JA |
83 | } |
84 | ||
d24c33a4 JA |
85 | static inline int ptr_valid(struct pool *pool, void *ptr) |
86 | { | |
dcb69098 | 87 | unsigned int pool_size = pool->nr_blocks * SMALLOC_BPL; |
ec996e9c JA |
88 | |
89 | return (ptr >= pool->map) && (ptr < pool->map + pool_size); | |
d24c33a4 JA |
90 | } |
91 | ||
808e9ea8 JA |
92 | static inline unsigned int size_to_blocks(unsigned int size) |
93 | { | |
94 | return (size + SMALLOC_BPB - 1) / SMALLOC_BPB; | |
95 | } | |
96 | ||
dcb69098 JA |
97 | static int blocks_iter(struct pool *pool, unsigned int pool_idx, |
98 | unsigned int idx, unsigned int nr_blocks, | |
ec996e9c | 99 | int (*func)(unsigned int *map, unsigned int mask)) |
d24c33a4 | 100 | { |
dcb69098 | 101 | |
ec996e9c JA |
102 | while (nr_blocks) { |
103 | unsigned int this_blocks, mask; | |
dcb69098 JA |
104 | unsigned int *map; |
105 | ||
106 | if (pool_idx >= pool->nr_blocks) | |
107 | return 0; | |
108 | ||
109 | map = &pool->bitmap[pool_idx]; | |
ec996e9c JA |
110 | |
111 | this_blocks = nr_blocks; | |
112 | if (this_blocks + idx > SMALLOC_BPI) { | |
113 | this_blocks = SMALLOC_BPI - idx; | |
114 | idx = SMALLOC_BPI - this_blocks; | |
115 | } | |
116 | ||
117 | if (this_blocks == SMALLOC_BPI) | |
118 | mask = -1U; | |
119 | else | |
120 | mask = ((1U << this_blocks) - 1) << idx; | |
121 | ||
122 | if (!func(map, mask)) | |
123 | return 0; | |
124 | ||
125 | nr_blocks -= this_blocks; | |
126 | idx = 0; | |
dcb69098 | 127 | pool_idx++; |
ec996e9c JA |
128 | } |
129 | ||
130 | return 1; | |
d24c33a4 JA |
131 | } |
132 | ||
ec996e9c | 133 | static int mask_cmp(unsigned int *map, unsigned int mask) |
d24c33a4 | 134 | { |
ec996e9c | 135 | return !(*map & mask); |
d24c33a4 JA |
136 | } |
137 | ||
ec996e9c | 138 | static int mask_clear(unsigned int *map, unsigned int mask) |
d24c33a4 | 139 | { |
dcb69098 | 140 | assert((*map & mask) == mask); |
ec996e9c JA |
141 | *map &= ~mask; |
142 | return 1; | |
d24c33a4 JA |
143 | } |
144 | ||
ec996e9c | 145 | static int mask_set(unsigned int *map, unsigned int mask) |
d24c33a4 | 146 | { |
dcb69098 | 147 | assert(!(*map & mask)); |
ec996e9c JA |
148 | *map |= mask; |
149 | return 1; | |
d24c33a4 JA |
150 | } |
151 | ||
dcb69098 JA |
152 | static int blocks_free(struct pool *pool, unsigned int pool_idx, |
153 | unsigned int idx, unsigned int nr_blocks) | |
d24c33a4 | 154 | { |
dcb69098 | 155 | return blocks_iter(pool, pool_idx, idx, nr_blocks, mask_cmp); |
d24c33a4 JA |
156 | } |
157 | ||
dcb69098 JA |
158 | static void set_blocks(struct pool *pool, unsigned int pool_idx, |
159 | unsigned int idx, unsigned int nr_blocks) | |
d24c33a4 | 160 | { |
dcb69098 | 161 | blocks_iter(pool, pool_idx, idx, nr_blocks, mask_set); |
d24c33a4 JA |
162 | } |
163 | ||
dcb69098 JA |
164 | static void clear_blocks(struct pool *pool, unsigned int pool_idx, |
165 | unsigned int idx, unsigned int nr_blocks) | |
d24c33a4 | 166 | { |
dcb69098 | 167 | blocks_iter(pool, pool_idx, idx, nr_blocks, mask_clear); |
d24c33a4 JA |
168 | } |
169 | ||
ec996e9c JA |
170 | static int find_next_zero(int word, int start) |
171 | { | |
172 | assert(word != -1U); | |
173 | word >>= (start + 1); | |
b3268b92 | 174 | return ffz(word) + start + 1; |
d24c33a4 JA |
175 | } |
176 | ||
adf57099 | 177 | static int add_pool(struct pool *pool, unsigned int alloc_size) |
d24c33a4 | 178 | { |
ec996e9c | 179 | int fd, bitmap_blocks; |
b8a6582e JA |
180 | char file[] = "/tmp/.fio_smalloc.XXXXXX"; |
181 | void *ptr; | |
ec996e9c | 182 | |
b8a6582e | 183 | fd = mkstemp(file); |
d24c33a4 JA |
184 | if (fd < 0) |
185 | goto out_close; | |
186 | ||
55f6491d | 187 | #ifdef SMALLOC_REDZONE |
ec996e9c | 188 | alloc_size += sizeof(unsigned int); |
55f6491d | 189 | #endif |
ec996e9c JA |
190 | alloc_size += sizeof(struct block_hdr); |
191 | if (alloc_size < INITIAL_SIZE) | |
192 | alloc_size = INITIAL_SIZE; | |
193 | ||
194 | /* round up to nearest full number of blocks */ | |
195 | alloc_size = (alloc_size + SMALLOC_BPL - 1) & ~(SMALLOC_BPL - 1); | |
196 | bitmap_blocks = alloc_size / SMALLOC_BPL; | |
197 | alloc_size += bitmap_blocks * sizeof(unsigned int); | |
198 | pool->mmap_size = alloc_size; | |
0b9d69ec | 199 | |
ec996e9c JA |
200 | pool->nr_blocks = bitmap_blocks; |
201 | pool->free_blocks = bitmap_blocks * SMALLOC_BPB; | |
adf57099 | 202 | |
ec996e9c | 203 | if (ftruncate(fd, alloc_size) < 0) |
d24c33a4 JA |
204 | goto out_unlink; |
205 | ||
ec996e9c | 206 | ptr = mmap(NULL, alloc_size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0); |
d24c33a4 JA |
207 | if (ptr == MAP_FAILED) |
208 | goto out_unlink; | |
209 | ||
ec996e9c JA |
210 | memset(ptr, 0, alloc_size); |
211 | pool->map = ptr; | |
212 | pool->bitmap = (void *) ptr + (pool->nr_blocks * SMALLOC_BPL); | |
d24c33a4 | 213 | |
6548f47f | 214 | pool->lock = fio_mutex_init(1); |
d24c33a4 JA |
215 | if (!pool->lock) |
216 | goto out_unlink; | |
d24c33a4 | 217 | |
443bb114 JA |
218 | /* |
219 | * Unlink pool file now. It wont get deleted until the fd is closed, | |
220 | * which happens both for cleanup or unexpected quit. This way we | |
221 | * don't leave temp files around in case of a crash. | |
222 | */ | |
b8a6582e | 223 | unlink(file); |
d24c33a4 JA |
224 | pool->fd = fd; |
225 | ||
d24c33a4 JA |
226 | nr_pools++; |
227 | return 0; | |
228 | out_unlink: | |
ec996e9c | 229 | fprintf(stderr, "smalloc: failed adding pool\n"); |
d24c33a4 | 230 | if (pool->map) |
ec996e9c | 231 | munmap(pool->map, pool->mmap_size); |
b8a6582e | 232 | unlink(file); |
d24c33a4 | 233 | out_close: |
b8a6582e | 234 | close(fd); |
d24c33a4 JA |
235 | return 1; |
236 | } | |
237 | ||
238 | void sinit(void) | |
239 | { | |
4d4e80f2 | 240 | int ret; |
d24c33a4 | 241 | |
6548f47f | 242 | lock = fio_mutex_rw_init(); |
adf57099 | 243 | ret = add_pool(&mp[0], INITIAL_SIZE); |
d24c33a4 JA |
244 | assert(!ret); |
245 | } | |
246 | ||
247 | static void cleanup_pool(struct pool *pool) | |
248 | { | |
443bb114 JA |
249 | /* |
250 | * This will also remove the temporary file we used as a backing | |
251 | * store, it was already unlinked | |
252 | */ | |
d24c33a4 | 253 | close(pool->fd); |
ec996e9c | 254 | munmap(pool->map, pool->mmap_size); |
6548f47f JA |
255 | |
256 | if (pool->lock) | |
257 | fio_mutex_remove(pool->lock); | |
d24c33a4 JA |
258 | } |
259 | ||
260 | void scleanup(void) | |
261 | { | |
262 | unsigned int i; | |
263 | ||
264 | for (i = 0; i < nr_pools; i++) | |
265 | cleanup_pool(&mp[i]); | |
266 | ||
6548f47f JA |
267 | if (lock) |
268 | fio_mutex_remove(lock); | |
d24c33a4 JA |
269 | } |
270 | ||
89da54e8 | 271 | #ifdef SMALLOC_REDZONE |
cf98708d JA |
272 | static void *postred_ptr(struct block_hdr *hdr) |
273 | { | |
cf98708d JA |
274 | unsigned long ptr; |
275 | ||
276 | ptr = (unsigned long) hdr + hdr->size - sizeof(unsigned int); | |
277 | ptr = (ptr + int_mask) & ~int_mask; | |
278 | ||
279 | return (void *) ptr; | |
280 | } | |
281 | ||
ec996e9c | 282 | static void fill_redzone(struct block_hdr *hdr) |
55f6491d | 283 | { |
cf98708d | 284 | unsigned int *postred = postred_ptr(hdr); |
55f6491d | 285 | |
ec996e9c JA |
286 | hdr->prered = SMALLOC_PRE_RED; |
287 | *postred = SMALLOC_POST_RED; | |
ec996e9c | 288 | } |
55f6491d | 289 | |
ec996e9c JA |
290 | static void sfree_check_redzone(struct block_hdr *hdr) |
291 | { | |
cf98708d | 292 | unsigned int *postred = postred_ptr(hdr); |
ec996e9c JA |
293 | |
294 | if (hdr->prered != SMALLOC_PRE_RED) { | |
55f6491d JA |
295 | fprintf(stderr, "smalloc pre redzone destroyed!\n"); |
296 | fprintf(stderr, " ptr=%p, prered=%x, expected %x\n", | |
ec996e9c | 297 | hdr, hdr->prered, SMALLOC_PRE_RED); |
55f6491d JA |
298 | assert(0); |
299 | } | |
300 | if (*postred != SMALLOC_POST_RED) { | |
301 | fprintf(stderr, "smalloc post redzone destroyed!\n"); | |
302 | fprintf(stderr, " ptr=%p, postred=%x, expected %x\n", | |
ec996e9c | 303 | hdr, *postred, SMALLOC_POST_RED); |
55f6491d JA |
304 | assert(0); |
305 | } | |
89da54e8 JA |
306 | } |
307 | #else | |
308 | static void fill_redzone(struct block_hdr *hdr) | |
309 | { | |
55f6491d JA |
310 | } |
311 | ||
89da54e8 JA |
312 | static void sfree_check_redzone(struct block_hdr *hdr) |
313 | { | |
314 | } | |
315 | #endif | |
316 | ||
d24c33a4 JA |
317 | static void sfree_pool(struct pool *pool, void *ptr) |
318 | { | |
ec996e9c | 319 | struct block_hdr *hdr; |
179446e0 | 320 | unsigned int i, idx; |
ec996e9c | 321 | unsigned long offset; |
d24c33a4 JA |
322 | |
323 | if (!ptr) | |
324 | return; | |
325 | ||
ec996e9c JA |
326 | ptr -= sizeof(*hdr); |
327 | hdr = ptr; | |
55f6491d | 328 | |
d24c33a4 JA |
329 | assert(ptr_valid(pool, ptr)); |
330 | ||
ec996e9c | 331 | sfree_check_redzone(hdr); |
d24c33a4 | 332 | |
ec996e9c JA |
333 | offset = ptr - pool->map; |
334 | i = offset / SMALLOC_BPL; | |
335 | idx = (offset % SMALLOC_BPL) / SMALLOC_BPB; | |
d24c33a4 | 336 | |
ec996e9c | 337 | pool_lock(pool); |
dcb69098 | 338 | clear_blocks(pool, i, idx, size_to_blocks(hdr->size)); |
ec996e9c JA |
339 | if (i < pool->next_non_full) |
340 | pool->next_non_full = i; | |
179446e0 | 341 | pool->free_blocks += size_to_blocks(hdr->size); |
d24c33a4 JA |
342 | pool_unlock(pool); |
343 | } | |
344 | ||
345 | void sfree(void *ptr) | |
346 | { | |
347 | struct pool *pool = NULL; | |
348 | unsigned int i; | |
349 | ||
8e5732e5 JA |
350 | if (!ptr) |
351 | return; | |
352 | ||
65864cf7 | 353 | global_read_lock(); |
d24c33a4 JA |
354 | |
355 | for (i = 0; i < nr_pools; i++) { | |
356 | if (ptr_valid(&mp[i], ptr)) { | |
357 | pool = &mp[i]; | |
358 | break; | |
359 | } | |
360 | } | |
361 | ||
65864cf7 | 362 | global_read_unlock(); |
d24c33a4 JA |
363 | |
364 | assert(pool); | |
365 | sfree_pool(pool, ptr); | |
366 | } | |
367 | ||
55f6491d | 368 | static void *__smalloc_pool(struct pool *pool, unsigned int size) |
d24c33a4 | 369 | { |
ec996e9c JA |
370 | unsigned int nr_blocks; |
371 | unsigned int i; | |
372 | unsigned int offset; | |
373 | unsigned int last_idx; | |
374 | void *ret = NULL; | |
d24c33a4 | 375 | |
d24c33a4 | 376 | pool_lock(pool); |
179446e0 JA |
377 | |
378 | nr_blocks = size_to_blocks(size); | |
ec996e9c | 379 | if (nr_blocks > pool->free_blocks) |
8e5732e5 | 380 | goto fail; |
5ec10eaa | 381 | |
ec996e9c JA |
382 | i = pool->next_non_full; |
383 | last_idx = 0; | |
384 | offset = -1U; | |
385 | while (i < pool->nr_blocks) { | |
386 | unsigned int idx; | |
d24c33a4 | 387 | |
ec996e9c JA |
388 | if (pool->bitmap[i] == -1U) { |
389 | i++; | |
390 | pool->next_non_full = i; | |
391 | last_idx = 0; | |
392 | continue; | |
393 | } | |
d24c33a4 | 394 | |
ec996e9c | 395 | idx = find_next_zero(pool->bitmap[i], last_idx); |
dcb69098 | 396 | if (!blocks_free(pool, i, idx, nr_blocks)) { |
ec996e9c JA |
397 | idx += nr_blocks; |
398 | if (idx < SMALLOC_BPI) | |
399 | last_idx = idx; | |
400 | else { | |
401 | last_idx = 0; | |
402 | while (idx >= SMALLOC_BPI) { | |
403 | i++; | |
404 | idx -= SMALLOC_BPI; | |
405 | } | |
406 | } | |
407 | continue; | |
d24c33a4 | 408 | } |
dcb69098 | 409 | set_blocks(pool, i, idx, nr_blocks); |
ec996e9c JA |
410 | offset = i * SMALLOC_BPL + idx * SMALLOC_BPB; |
411 | break; | |
412 | } | |
413 | ||
414 | if (i < pool->nr_blocks) { | |
415 | pool->free_blocks -= nr_blocks; | |
416 | ret = pool->map + offset; | |
d24c33a4 | 417 | } |
ec996e9c | 418 | fail: |
d24c33a4 | 419 | pool_unlock(pool); |
ec996e9c | 420 | return ret; |
d24c33a4 JA |
421 | } |
422 | ||
55f6491d JA |
423 | static void *smalloc_pool(struct pool *pool, unsigned int size) |
424 | { | |
89da54e8 | 425 | unsigned int alloc_size = size + sizeof(struct block_hdr); |
55f6491d JA |
426 | void *ptr; |
427 | ||
cf98708d | 428 | /* |
122426da JA |
429 | * Round to int alignment, so that the postred pointer will |
430 | * be naturally aligned as well. | |
cf98708d | 431 | */ |
ec996e9c | 432 | #ifdef SMALLOC_REDZONE |
122426da JA |
433 | alloc_size += sizeof(unsigned int); |
434 | alloc_size = (alloc_size + int_mask) & ~int_mask; | |
ec996e9c JA |
435 | #endif |
436 | ||
437 | ptr = __smalloc_pool(pool, alloc_size); | |
89da54e8 JA |
438 | if (ptr) { |
439 | struct block_hdr *hdr = ptr; | |
55f6491d | 440 | |
89da54e8 JA |
441 | hdr->size = alloc_size; |
442 | fill_redzone(hdr); | |
55f6491d | 443 | |
89da54e8 JA |
444 | ptr += sizeof(*hdr); |
445 | memset(ptr, 0, size); | |
446 | } | |
ec996e9c | 447 | |
55f6491d | 448 | return ptr; |
55f6491d JA |
449 | } |
450 | ||
d24c33a4 JA |
451 | void *smalloc(unsigned int size) |
452 | { | |
453 | unsigned int i; | |
454 | ||
d1271dc1 | 455 | global_write_lock(); |
d24c33a4 JA |
456 | i = last_pool; |
457 | ||
458 | do { | |
459 | for (; i < nr_pools; i++) { | |
460 | void *ptr = smalloc_pool(&mp[i], size); | |
461 | ||
462 | if (ptr) { | |
463 | last_pool = i; | |
d1271dc1 | 464 | global_write_unlock(); |
d24c33a4 JA |
465 | return ptr; |
466 | } | |
467 | } | |
468 | if (last_pool) { | |
469 | last_pool = 0; | |
470 | continue; | |
471 | } | |
472 | ||
ec996e9c | 473 | if (nr_pools + 1 > MAX_POOLS) |
d24c33a4 JA |
474 | break; |
475 | else { | |
476 | i = nr_pools; | |
adf57099 | 477 | if (add_pool(&mp[nr_pools], size)) |
65864cf7 | 478 | goto out; |
d24c33a4 JA |
479 | } |
480 | } while (1); | |
481 | ||
65864cf7 | 482 | out: |
d1271dc1 | 483 | global_write_unlock(); |
d24c33a4 JA |
484 | return NULL; |
485 | } | |
486 | ||
487 | char *smalloc_strdup(const char *str) | |
488 | { | |
489 | char *ptr; | |
490 | ||
491 | ptr = smalloc(strlen(str) + 1); | |
492 | strcpy(ptr, str); | |
493 | return ptr; | |
494 | } |