sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1 | |
| 2 | /*--------------------------------------------------------------------*/ |
| 3 | /*--- An implementation of malloc/free which doesn't use sbrk. ---*/ |
| 4 | /*--- vg_malloc2.c ---*/ |
| 5 | /*--------------------------------------------------------------------*/ |
| 6 | |
| 7 | /* |
| 8 | This file is part of Valgrind, an x86 protected-mode emulator |
| 9 | designed for debugging and profiling binaries on x86-Unixes. |
| 10 | |
| 11 | Copyright (C) 2000-2002 Julian Seward |
| 12 | jseward@acm.org |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 13 | |
| 14 | This program is free software; you can redistribute it and/or |
| 15 | modify it under the terms of the GNU General Public License as |
| 16 | published by the Free Software Foundation; either version 2 of the |
| 17 | License, or (at your option) any later version. |
| 18 | |
| 19 | This program is distributed in the hope that it will be useful, but |
| 20 | WITHOUT ANY WARRANTY; without even the implied warranty of |
| 21 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 22 | General Public License for more details. |
| 23 | |
| 24 | You should have received a copy of the GNU General Public License |
| 25 | along with this program; if not, write to the Free Software |
| 26 | Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 27 | 02111-1307, USA. |
| 28 | |
| 29 | The GNU General Public License is contained in the file LICENSE. |
| 30 | */ |
| 31 | |
| 32 | |
| 33 | #include "vg_include.h" |
| 34 | |
| 35 | /* Define to turn on (heavyweight) debugging machinery. */ |
| 36 | /* #define DEBUG_MALLOC */ |
| 37 | |
| 38 | |
| 39 | /*------------------------------------------------------------*/ |
| 40 | /*--- Structs n stuff ---*/ |
| 41 | /*------------------------------------------------------------*/ |
| 42 | |
| 43 | #define VG_REDZONE_LO_MASK 0x31415927 |
| 44 | #define VG_REDZONE_HI_MASK 0x14141356 |
| 45 | |
| 46 | #define VG_N_MALLOC_LISTS 16 /* do not change this */ |
| 47 | |
| 48 | |
| 49 | typedef UInt Word; |
| 50 | typedef Word WordF; |
| 51 | typedef Word WordL; |
| 52 | |
| 53 | |
| 54 | /* A superblock. */ |
| 55 | typedef |
| 56 | struct _Superblock { |
| 57 | struct _Superblock* next; |
| 58 | /* number of payload words in this superblock. */ |
| 59 | Int n_payload_words; |
| 60 | Word payload_words[0]; |
| 61 | } |
| 62 | Superblock; |
| 63 | |
| 64 | |
| 65 | /* An arena. */ |
| 66 | typedef |
| 67 | struct { |
| 68 | Char* name; |
| 69 | Int rz_szW; /* Red zone size in words */ |
| 70 | Bool rz_check; /* Check red-zone on free? */ |
| 71 | Int min_sblockW; /* Minimum superblock size */ |
| 72 | WordF* freelist[VG_N_MALLOC_LISTS]; |
| 73 | Superblock* sblocks; |
| 74 | /* Stats only. */ |
| 75 | UInt bytes_on_loan; |
| 76 | UInt bytes_mmaped; |
| 77 | UInt bytes_on_loan_max; |
| 78 | } |
| 79 | Arena; |
| 80 | |
| 81 | |
| 82 | /* Block layout: |
| 83 | |
| 84 | this block total sizeW (1 word) |
| 85 | freelist previous ptr (1 word) |
| 86 | freelist next ptr (1 word) |
| 87 | red zone words (depends on .rz_szW field of Arena) |
| 88 | (payload words) |
| 89 | red zone words (depends on .rz_szW field of Arena) |
| 90 | this block total sizeW (1 word) |
| 91 | |
| 92 | Total size in words (bszW) and payload size in words (pszW) |
| 93 | are related by |
| 94 | bszW == pszW + 4 + 2 * a->rz_szW |
| 95 | |
| 96 | Furthermore, both size fields in the block are negative if it is |
| 97 | not in use, and positive if it is in use. A block size of zero |
| 98 | is not possible, because a block always has at least four words |
| 99 | of overhead. |
| 100 | */ |
| 101 | typedef |
| 102 | struct { |
| 103 | Int bszW_lo; |
| 104 | Word* prev; |
| 105 | Word* next; |
| 106 | Word redzone[0]; |
| 107 | } |
| 108 | BlockHeader; |
| 109 | |
| 110 | |
| 111 | /*------------------------------------------------------------*/ |
| 112 | /*--- Forwardses ... and misc ... ---*/ |
| 113 | /*------------------------------------------------------------*/ |
| 114 | |
| 115 | static Bool blockSane ( Arena* a, Word* b ); |
| 116 | |
| 117 | /* Align ptr p upwards to an align-sized boundary. */ |
| 118 | static |
| 119 | void* align_upwards ( void* p, Int align ) |
| 120 | { |
| 121 | Addr a = (Addr)p; |
| 122 | if ((a % align) == 0) return (void*)a; |
| 123 | return (void*)(a - (a % align) + align); |
| 124 | } |
| 125 | |
| 126 | |
| 127 | /*------------------------------------------------------------*/ |
| 128 | /*--- Arena management stuff ---*/ |
| 129 | /*------------------------------------------------------------*/ |
| 130 | |
| 131 | /* The arena structures themselves. */ |
| 132 | static Arena vg_arena[VG_N_ARENAS]; |
| 133 | |
| 134 | /* Functions external to this module identify arenas using ArenaIds, |
| 135 | not Arena*s. This fn converts the former to the latter. */ |
| 136 | static Arena* arenaId_to_ArenaP ( ArenaId arena ) |
| 137 | { |
| 138 | vg_assert(arena >= 0 && arena < VG_N_ARENAS); |
| 139 | return & vg_arena[arena]; |
| 140 | } |
| 141 | |
| 142 | |
| 143 | /* Initialise an arena. */ |
| 144 | static |
| 145 | void arena_init ( Arena* a, Char* name, |
| 146 | Int rz_szW, Bool rz_check, Int min_sblockW ) |
| 147 | { |
| 148 | Int i; |
| 149 | vg_assert((min_sblockW % VKI_WORDS_PER_PAGE) == 0); |
| 150 | a->name = name; |
| 151 | a->rz_szW = rz_szW; |
| 152 | a->rz_check = rz_check; |
| 153 | a->min_sblockW = min_sblockW; |
| 154 | for (i = 0; i < VG_N_MALLOC_LISTS; i++) a->freelist[i] = NULL; |
| 155 | a->sblocks = NULL; |
| 156 | a->bytes_on_loan = 0; |
| 157 | a->bytes_mmaped = 0; |
| 158 | a->bytes_on_loan_max = 0; |
| 159 | } |
| 160 | |
| 161 | |
| 162 | /* Print vital stats for an arena. */ |
| 163 | void VG_(show_all_arena_stats) ( void ) |
| 164 | { |
| 165 | Int i; |
| 166 | for (i = 0; i < VG_N_ARENAS; i++) { |
| 167 | VG_(message)(Vg_DebugMsg, |
| 168 | "Arena `%s': %7d max useful, %7d mmap'd, %7d current useful", |
| 169 | vg_arena[i].name, |
| 170 | vg_arena[i].bytes_on_loan_max, |
| 171 | vg_arena[i].bytes_mmaped, |
| 172 | vg_arena[i].bytes_on_loan |
| 173 | ); |
| 174 | } |
| 175 | } |
| 176 | |
| 177 | |
| 178 | /* It is important that this library is self-initialising, because it |
| 179 | may get called very early on -- as a result of C++ static |
| 180 | constructor initialisations -- before Valgrind itself is |
| 181 | initialised. Hence vg_malloc() and vg_free() below always call |
| 182 | ensure_mm_init() to ensure things are correctly initialised. */ |
| 183 | |
| 184 | static |
| 185 | void ensure_mm_init ( void ) |
| 186 | { |
| 187 | static Bool init_done = False; |
| 188 | if (init_done) return; |
| 189 | |
| 190 | /* Use a checked red zone size of 1 word for our internal stuff, |
| 191 | and an unchecked zone of arbitrary size for the client. Of |
| 192 | course the client's red zone is checked really, but using the |
| 193 | addressibility maps, not by the mechanism implemented here, |
| 194 | which merely checks at the time of freeing that the red zone |
| 195 | words are unchanged. */ |
| 196 | |
| 197 | arena_init ( &vg_arena[VG_AR_PRIVATE], "private ", |
| 198 | 1, True, 262144 ); |
| 199 | |
| 200 | arena_init ( &vg_arena[VG_AR_SYMTAB], "symtab ", |
| 201 | 1, True, 262144 ); |
| 202 | |
| 203 | arena_init ( &vg_arena[VG_AR_CLIENT], "client ", |
| 204 | VG_AR_CLIENT_REDZONE_SZW, False, 262144 ); |
| 205 | |
| 206 | arena_init ( &vg_arena[VG_AR_DEMANGLE], "demangle", |
| 207 | 4 /*paranoid*/, True, 16384 ); |
| 208 | |
| 209 | arena_init ( &vg_arena[VG_AR_EXECTXT], "exectxt ", |
| 210 | 1, True, 16384 ); |
| 211 | |
| 212 | arena_init ( &vg_arena[VG_AR_ERRCTXT], "errctxt ", |
| 213 | 1, True, 16384 ); |
| 214 | |
| 215 | arena_init ( &vg_arena[VG_AR_TRANSIENT], "transien", |
| 216 | 2, True, 16384 ); |
| 217 | |
| 218 | init_done = True; |
| 219 | # ifdef DEBUG_MALLOC |
| 220 | VG_(mallocSanityCheckAll)(); |
| 221 | # endif |
| 222 | } |
| 223 | |
| 224 | |
| 225 | /*------------------------------------------------------------*/ |
| 226 | /*--- Arena management stuff ---*/ |
| 227 | /*------------------------------------------------------------*/ |
| 228 | |
| 229 | static |
| 230 | Superblock* newSuperblock ( Arena* a, Int cszW ) |
| 231 | { |
| 232 | Superblock* sb; |
| 233 | cszW += 2; /* Take into account sb->next and sb->n_words fields */ |
| 234 | if (cszW < a->min_sblockW) cszW = a->min_sblockW; |
| 235 | while ((cszW % VKI_WORDS_PER_PAGE) > 0) cszW++; |
| 236 | sb = VG_(get_memory_from_mmap) ( cszW * sizeof(Word) ); |
| 237 | sb->n_payload_words = cszW - 2; |
| 238 | a->bytes_mmaped += cszW * sizeof(Word); |
| 239 | if (0) |
| 240 | VG_(message)(Vg_DebugMsg, "newSuperblock, %d payload words", |
| 241 | sb->n_payload_words); |
| 242 | return sb; |
| 243 | } |
| 244 | |
| 245 | |
| 246 | /* Find the superblock containing the given chunk. */ |
| 247 | static |
| 248 | Superblock* findSb ( Arena* a, UInt* ch ) |
| 249 | { |
| 250 | Superblock* sb; |
| 251 | for (sb = a->sblocks; sb; sb = sb->next) |
| 252 | if (&sb->payload_words[0] <= ch |
| 253 | && ch < &sb->payload_words[sb->n_payload_words]) |
| 254 | return sb; |
| 255 | VG_(printf)("findSb: can't find pointer %p in arena `%s'\n", |
| 256 | ch, a->name ); |
| 257 | VG_(panic)("findSb: vg_free() in wrong arena?"); |
| 258 | return NULL; /*NOTREACHED*/ |
| 259 | } |
| 260 | |
| 261 | |
| 262 | /*------------------------------------------------------------*/ |
| 263 | /*--- Low-level functions for working with blocks. ---*/ |
| 264 | /*------------------------------------------------------------*/ |
| 265 | |
| 266 | /* Add the not-in-use attribute to a bszW. */ |
| 267 | static __inline__ |
| 268 | Int mk_free_bszW ( Int bszW ) |
| 269 | { |
| 270 | vg_assert(bszW != 0); |
| 271 | return (bszW < 0) ? bszW : -bszW; |
| 272 | } |
| 273 | |
| 274 | /* Add the in-use attribute to a bszW. */ |
| 275 | static __inline__ |
| 276 | Int mk_inuse_bszW ( Int bszW ) |
| 277 | { |
| 278 | vg_assert(bszW != 0); |
| 279 | return (bszW < 0) ? -bszW : bszW; |
| 280 | } |
| 281 | |
| 282 | /* Remove the in-use/not-in-use attribute from a bszW, leaving just |
| 283 | the size. */ |
| 284 | static __inline__ |
| 285 | Int mk_plain_bszW ( Int bszW ) |
| 286 | { |
| 287 | vg_assert(bszW != 0); |
| 288 | return (bszW < 0) ? -bszW : bszW; |
| 289 | } |
| 290 | |
| 291 | /* Does this bszW have the in-use attribute ? */ |
| 292 | static __inline__ |
| 293 | Bool is_inuse_bszW ( Int bszW ) |
| 294 | { |
| 295 | vg_assert(bszW != 0); |
| 296 | return (bszW < 0) ? False : True; |
| 297 | } |
| 298 | |
| 299 | |
| 300 | /* Given the addr of the first word of a block, return the addr of the |
| 301 | last word. */ |
| 302 | static __inline__ |
| 303 | WordL* first_to_last ( WordF* fw ) |
| 304 | { |
| 305 | return fw + mk_plain_bszW(fw[0]) - 1; |
| 306 | } |
| 307 | |
| 308 | /* Given the addr of the last word of a block, return the addr of the |
| 309 | first word. */ |
| 310 | static __inline__ |
| 311 | WordF* last_to_first ( WordL* lw ) |
| 312 | { |
| 313 | return lw - mk_plain_bszW(lw[0]) + 1; |
| 314 | } |
| 315 | |
| 316 | |
| 317 | /* Given the addr of the first word of a block, return the addr of the |
| 318 | first word of its payload. */ |
| 319 | static __inline__ |
| 320 | Word* first_to_payload ( Arena* a, WordF* fw ) |
| 321 | { |
| 322 | return & fw[3 + a->rz_szW]; |
| 323 | } |
| 324 | |
| 325 | /* Given the addr of the first word of a the payload of a block, |
| 326 | return the addr of the first word of the block. */ |
| 327 | static __inline__ |
| 328 | Word* payload_to_first ( Arena* a, WordF* payload ) |
| 329 | { |
| 330 | return & payload[- 3 - a->rz_szW]; |
| 331 | } |
| 332 | |
| 333 | /* Set and get the lower size field of a block. */ |
| 334 | static __inline__ |
| 335 | void set_bszW_lo ( WordF* fw, Int bszW ) { |
| 336 | fw[0] = bszW; |
| 337 | } |
| 338 | static __inline__ |
| 339 | Int get_bszW_lo ( WordF* fw ) |
| 340 | { |
| 341 | return fw[0]; |
| 342 | } |
| 343 | |
| 344 | |
| 345 | /* Set and get the next and previous link fields of a block. */ |
| 346 | static __inline__ |
| 347 | void set_prev_p ( WordF* fw, Word* prev_p ) { |
| 348 | fw[1] = (Word)prev_p; |
| 349 | } |
| 350 | static __inline__ |
| 351 | void set_next_p ( WordF* fw, Word* next_p ) { |
| 352 | fw[2] = (Word)next_p; |
| 353 | } |
| 354 | static __inline__ |
| 355 | Word* get_prev_p ( WordF* fw ) { |
| 356 | return (Word*)(fw[1]); |
| 357 | } |
| 358 | static __inline__ |
| 359 | Word* get_next_p ( WordF* fw ) { |
| 360 | return (Word*)(fw[2]); |
| 361 | } |
| 362 | |
| 363 | |
| 364 | /* Set and get the upper size field of a block. */ |
| 365 | static __inline__ |
| 366 | void set_bszW_hi ( WordF* fw, Int bszW ) { |
| 367 | WordL* lw = first_to_last(fw); |
| 368 | vg_assert(lw == fw + mk_plain_bszW(bszW) - 1); |
| 369 | lw[0] = bszW; |
| 370 | } |
| 371 | static __inline__ |
| 372 | Int get_bszW_hi ( WordF* fw ) { |
| 373 | WordL* lw = first_to_last(fw); |
| 374 | return lw[0]; |
| 375 | } |
| 376 | |
| 377 | /* Get the upper size field of a block, given a pointer to the last |
| 378 | word of it. */ |
| 379 | static __inline__ |
| 380 | Int get_bszW_hi_from_last_word ( WordL* lw ) { |
| 381 | WordF* fw = last_to_first(lw); |
| 382 | return get_bszW_lo(fw); |
| 383 | } |
| 384 | |
| 385 | |
| 386 | /* Read and write the lower and upper red-zone words of a block. */ |
| 387 | static __inline__ |
| 388 | void set_rz_lo_word ( Arena* a, WordF* fw, Int rz_wordno, Word w ) |
| 389 | { |
| 390 | fw[3 + rz_wordno] = w; |
| 391 | } |
| 392 | static __inline__ |
| 393 | void set_rz_hi_word ( Arena* a, WordF* fw, Int rz_wordno, Word w ) |
| 394 | { |
| 395 | WordL* lw = first_to_last(fw); |
| 396 | lw[-1-rz_wordno] = w; |
| 397 | } |
| 398 | static __inline__ |
| 399 | Word get_rz_lo_word ( Arena* a, WordF* fw, Int rz_wordno ) |
| 400 | { |
| 401 | return fw[3 + rz_wordno]; |
| 402 | } |
| 403 | static __inline__ |
| 404 | Word get_rz_hi_word ( Arena* a, WordF* fw, Int rz_wordno ) |
| 405 | { |
| 406 | WordL* lw = first_to_last(fw); |
| 407 | return lw[-1-rz_wordno]; |
| 408 | } |
| 409 | |
| 410 | |
| 411 | /* Return the lower, upper and total overhead in words for a block. |
| 412 | These are determined purely by which arena the block lives in. */ |
| 413 | static __inline__ |
| 414 | Int overhead_szW_lo ( Arena* a ) |
| 415 | { |
| 416 | return 3 + a->rz_szW; |
| 417 | } |
| 418 | static __inline__ |
| 419 | Int overhead_szW_hi ( Arena* a ) |
| 420 | { |
| 421 | return 1 + a->rz_szW; |
| 422 | } |
| 423 | static __inline__ |
| 424 | Int overhead_szW ( Arena* a ) |
| 425 | { |
| 426 | return overhead_szW_lo(a) + overhead_szW_hi(a); |
| 427 | } |
| 428 | |
| 429 | |
| 430 | /* Convert pointer size in words to block size in words, and back. */ |
| 431 | static __inline__ |
| 432 | Int pszW_to_bszW ( Arena* a, Int pszW ) |
| 433 | { |
| 434 | vg_assert(pszW >= 0); |
| 435 | return pszW + overhead_szW(a); |
| 436 | } |
| 437 | static __inline__ |
| 438 | Int bszW_to_pszW ( Arena* a, Int bszW ) |
| 439 | { |
| 440 | Int pszW = bszW - overhead_szW(a); |
| 441 | vg_assert(pszW >= 0); |
| 442 | return pszW; |
| 443 | } |
| 444 | |
| 445 | /*------------------------------------------------------------*/ |
| 446 | /*--- Functions for working with freelists. ---*/ |
| 447 | /*------------------------------------------------------------*/ |
| 448 | |
| 449 | /* Determination of which freelist a block lives on is based on the |
| 450 | payload size, not block size, in words. */ |
| 451 | |
| 452 | /* Convert a payload size in words to a freelist number. */ |
| 453 | |
| 454 | static |
| 455 | Int pszW_to_listNo ( Int pszW ) |
| 456 | { |
| 457 | vg_assert(pszW >= 0); |
| 458 | if (pszW <= 3) return 0; |
| 459 | if (pszW <= 4) return 1; |
| 460 | if (pszW <= 5) return 2; |
| 461 | if (pszW <= 6) return 3; |
| 462 | if (pszW <= 7) return 4; |
| 463 | if (pszW <= 8) return 5; |
| 464 | if (pszW <= 9) return 6; |
| 465 | if (pszW <= 10) return 7; |
| 466 | if (pszW <= 11) return 8; |
| 467 | if (pszW <= 12) return 9; |
| 468 | if (pszW <= 16) return 10; |
| 469 | if (pszW <= 32) return 11; |
| 470 | if (pszW <= 64) return 12; |
| 471 | if (pszW <= 128) return 13; |
| 472 | if (pszW <= 256) return 14; |
| 473 | return 15; |
| 474 | } |
| 475 | |
| 476 | |
| 477 | /* What are the minimum and maximum payload sizes for a given list? */ |
| 478 | |
| 479 | static |
| 480 | Int listNo_to_pszW_min ( Int listNo ) |
| 481 | { |
| 482 | Int pszW = 0; |
| 483 | vg_assert(listNo >= 0 && listNo <= VG_N_MALLOC_LISTS); |
| 484 | while (pszW_to_listNo(pszW) < listNo) pszW++; |
| 485 | return pszW; |
| 486 | } |
| 487 | |
| 488 | static |
| 489 | Int listNo_to_pszW_max ( Int listNo ) |
| 490 | { |
| 491 | vg_assert(listNo >= 0 && listNo <= VG_N_MALLOC_LISTS); |
| 492 | if (listNo == VG_N_MALLOC_LISTS-1) { |
| 493 | return 999999999; |
| 494 | } else { |
| 495 | return listNo_to_pszW_min(listNo+1) - 1; |
| 496 | } |
| 497 | } |
| 498 | |
| 499 | |
| 500 | /* A nasty hack to try and reduce fragmentation. Try and replace |
| 501 | a->freelist[lno] with another block on the same list but with a |
| 502 | lower address, with the idea of attempting to recycle the same |
| 503 | blocks rather than cruise through the address space. */ |
| 504 | |
| 505 | static |
| 506 | void swizzle ( Arena* a, Int lno ) |
| 507 | { |
| 508 | UInt* p_best; |
| 509 | UInt* pp; |
| 510 | UInt* pn; |
| 511 | Int i; |
| 512 | |
| 513 | p_best = a->freelist[lno]; |
| 514 | if (p_best == NULL) return; |
| 515 | |
| 516 | pn = pp = p_best; |
| 517 | for (i = 0; i < 20; i++) { |
| 518 | pn = get_next_p(pn); |
| 519 | pp = get_prev_p(pp); |
| 520 | if (pn < p_best) p_best = pn; |
| 521 | if (pp < p_best) p_best = pp; |
| 522 | } |
| 523 | if (p_best < a->freelist[lno]) { |
| 524 | # ifdef DEBUG_MALLOC |
| 525 | VG_(printf)("retreat by %d\n", |
| 526 | ((Char*)(a->freelist[lno])) - ((Char*)p_best)); |
| 527 | # endif |
| 528 | a->freelist[lno] = p_best; |
| 529 | } |
| 530 | } |
| 531 | |
| 532 | |
| 533 | /*------------------------------------------------------------*/ |
| 534 | /*--- Creating and deleting blocks. ---*/ |
| 535 | /*------------------------------------------------------------*/ |
| 536 | |
| 537 | /* Mark the words at b .. b+bszW-1 as not in use, and add them to the |
| 538 | relevant free list. */ |
| 539 | |
| 540 | static |
| 541 | void mkFreeBlock ( Arena* a, Word* b, Int bszW, Int b_lno ) |
| 542 | { |
| 543 | Int pszW = bszW_to_pszW(a, bszW); |
| 544 | vg_assert(pszW >= 0); |
| 545 | vg_assert(b_lno == pszW_to_listNo(pszW)); |
| 546 | /* Set the size fields and indicate not-in-use. */ |
| 547 | set_bszW_lo(b, mk_free_bszW(bszW)); |
| 548 | set_bszW_hi(b, mk_free_bszW(bszW)); |
| 549 | |
| 550 | /* Add to the relevant list. */ |
| 551 | if (a->freelist[b_lno] == NULL) { |
| 552 | set_prev_p(b, b); |
| 553 | set_next_p(b, b); |
| 554 | a->freelist[b_lno] = b; |
| 555 | } else { |
| 556 | Word* b_prev = get_prev_p(a->freelist[b_lno]); |
| 557 | Word* b_next = a->freelist[b_lno]; |
| 558 | set_next_p(b_prev, b); |
| 559 | set_prev_p(b_next, b); |
| 560 | set_next_p(b, b_next); |
| 561 | set_prev_p(b, b_prev); |
| 562 | } |
| 563 | # ifdef DEBUG_MALLOC |
| 564 | (void)blockSane(a,b); |
| 565 | # endif |
| 566 | } |
| 567 | |
| 568 | |
| 569 | /* Mark the words at b .. b+bszW-1 as in use, and set up the block |
| 570 | appropriately. */ |
| 571 | static |
| 572 | void mkInuseBlock ( Arena* a, UInt* b, UInt bszW ) |
| 573 | { |
| 574 | Int i; |
| 575 | set_bszW_lo(b, mk_inuse_bszW(bszW)); |
| 576 | set_bszW_hi(b, mk_inuse_bszW(bszW)); |
| 577 | set_prev_p(b, NULL); |
| 578 | set_next_p(b, NULL); |
| 579 | if (a->rz_check) { |
| 580 | for (i = 0; i < a->rz_szW; i++) { |
| 581 | set_rz_lo_word(a, b, i, (UInt)b ^ VG_REDZONE_LO_MASK); |
| 582 | set_rz_hi_word(a, b, i, (UInt)b ^ VG_REDZONE_HI_MASK); |
| 583 | } |
| 584 | } |
| 585 | # ifdef DEBUG_MALLOC |
| 586 | (void)blockSane(a,b); |
| 587 | # endif |
| 588 | } |
| 589 | |
| 590 | |
| 591 | /* Remove a block from a given list. Does no sanity checking. */ |
| 592 | static |
| 593 | void unlinkBlock ( Arena* a, UInt* b, Int listno ) |
| 594 | { |
| 595 | vg_assert(listno >= 0 && listno < VG_N_MALLOC_LISTS); |
| 596 | if (get_prev_p(b) == b) { |
| 597 | /* Only one element in the list; treat it specially. */ |
| 598 | vg_assert(get_next_p(b) == b); |
| 599 | a->freelist[listno] = NULL; |
| 600 | } else { |
| 601 | UInt* b_prev = get_prev_p(b); |
| 602 | UInt* b_next = get_next_p(b); |
| 603 | a->freelist[listno] = b_prev; |
| 604 | set_next_p(b_prev, b_next); |
| 605 | set_prev_p(b_next, b_prev); |
| 606 | swizzle ( a, listno ); |
| 607 | } |
| 608 | set_prev_p(b, NULL); |
| 609 | set_next_p(b, NULL); |
| 610 | } |
| 611 | |
| 612 | |
| 613 | /* Split an existing free block into two pieces, and put the fragment |
| 614 | (the second one along in memory) onto the relevant free list. |
| 615 | req_bszW is the required size of the block which isn't the |
| 616 | fragment. */ |
| 617 | static |
| 618 | void splitChunk ( Arena* a, UInt* b, Int b_listno, UInt req_bszW ) |
| 619 | { |
| 620 | Int b_bszW, frag_bszW; |
| 621 | b_bszW = mk_plain_bszW(get_bszW_lo(b)); |
| 622 | vg_assert(req_bszW < b_bszW); |
| 623 | frag_bszW = b_bszW - req_bszW; |
| 624 | vg_assert(frag_bszW >= overhead_szW(a)); |
| 625 | /* |
| 626 | printf( "split %d into %d and %d\n", |
| 627 | b_bszW,req_bszW,frag_bszW ); |
| 628 | */ |
| 629 | vg_assert(bszW_to_pszW(a, frag_bszW) > 0); |
| 630 | unlinkBlock(a, b, b_listno); |
| 631 | mkInuseBlock(a, b, req_bszW); |
| 632 | mkFreeBlock(a, &b[req_bszW], frag_bszW, |
| 633 | pszW_to_listNo(bszW_to_pszW(a, frag_bszW))); |
| 634 | } |
| 635 | |
| 636 | |
| 637 | /*------------------------------------------------------------*/ |
| 638 | /*--- Sanity-check/debugging machinery. ---*/ |
| 639 | /*------------------------------------------------------------*/ |
| 640 | |
| 641 | /* Do some crude sanity checks on a chunk. */ |
| 642 | static |
| 643 | Bool blockSane ( Arena* a, Word* b ) |
| 644 | { |
| 645 | # define BLEAT(str) VG_(printf)("blockSane: fail -- %s\n",str) |
| 646 | Int i; |
| 647 | if (get_bszW_lo(b) != get_bszW_hi(b)) |
| 648 | {BLEAT("sizes");return False;} |
| 649 | if (a->rz_check && is_inuse_bszW(get_bszW_lo(b))) { |
| 650 | for (i = 0; i < a->rz_szW; i++) { |
| 651 | if (get_rz_lo_word(a, b, i) != ((Word)b ^ VG_REDZONE_LO_MASK)) |
| 652 | {BLEAT("redzone-lo");return False;} |
| 653 | if (get_rz_hi_word(a, b, i) != ((Word)b ^ VG_REDZONE_HI_MASK)) |
| 654 | {BLEAT("redzone-hi");return False;} |
| 655 | } |
| 656 | } |
| 657 | return True; |
| 658 | # undef BLEAT |
| 659 | } |
| 660 | |
| 661 | |
| 662 | /* Print superblocks (only for debugging). */ |
| 663 | static |
| 664 | void ppSuperblocks ( Arena* a ) |
| 665 | { |
| 666 | Int i, ch_bszW, blockno; |
| 667 | UInt* ch; |
| 668 | Superblock* sb = a->sblocks; |
| 669 | blockno = 1; |
| 670 | |
| 671 | while (sb) { |
| 672 | VG_(printf)( "\n" ); |
| 673 | VG_(printf)( "superblock %d at %p, sb->n_pl_ws = %d, next = %p\n", |
| 674 | blockno++, sb, sb->n_payload_words, sb->next ); |
| 675 | i = 0; |
| 676 | while (True) { |
| 677 | if (i >= sb->n_payload_words) break; |
| 678 | ch = &sb->payload_words[i]; |
| 679 | ch_bszW = get_bszW_lo(ch); |
| 680 | VG_(printf)( " block at %d, bszW %d: ", i, mk_plain_bszW(ch_bszW) ); |
| 681 | VG_(printf)( "%s, ", is_inuse_bszW(ch_bszW) ? "inuse" : "free" ); |
| 682 | VG_(printf)( "%s\n", blockSane(a,ch) ? "ok" : "BAD" ); |
| 683 | i += mk_plain_bszW(ch_bszW); |
| 684 | } |
| 685 | if (i > sb->n_payload_words) |
| 686 | VG_(printf)( " last block overshoots end of SB\n"); |
| 687 | sb = sb->next; |
| 688 | } |
| 689 | VG_(printf)( "end of superblocks\n\n" ); |
| 690 | } |
| 691 | |
| 692 | |
| 693 | /* Sanity check both the superblocks and the chains. */ |
| 694 | void VG_(mallocSanityCheckArena) ( ArenaId aid ) |
| 695 | { |
| 696 | Int i, superblockctr, b_bszW, b_pszW, blockctr_sb, blockctr_li; |
| 697 | Int blockctr_sb_free, listno, list_min_pszW, list_max_pszW; |
| 698 | Superblock* sb; |
| 699 | Bool thisFree, lastWasFree; |
| 700 | Word* b; |
| 701 | Word* b_prev; |
| 702 | UInt arena_bytes_on_loan; |
| 703 | Arena* a; |
| 704 | |
| 705 | # define BOMB VG_(panic)("vg_mallocSanityCheckArena") |
| 706 | |
| 707 | a = arenaId_to_ArenaP(aid); |
| 708 | |
| 709 | /* First, traverse all the superblocks, inspecting the chunks in |
| 710 | each. */ |
| 711 | superblockctr = blockctr_sb = blockctr_sb_free = 0; |
| 712 | arena_bytes_on_loan = 0; |
| 713 | sb = a->sblocks; |
| 714 | while (sb) { |
| 715 | lastWasFree = False; |
| 716 | superblockctr++; |
| 717 | i = 0; |
| 718 | while (True) { |
| 719 | if (i >= sb->n_payload_words) break; |
| 720 | blockctr_sb++; |
| 721 | b = &sb->payload_words[i]; |
| 722 | b_bszW = get_bszW_lo(b); |
| 723 | if (!blockSane(a, b)) { |
| 724 | VG_(printf)( "mallocSanityCheck: sb %p, block %d (bszW %d): " |
| 725 | "BAD\n", |
| 726 | sb, i, b_bszW ); |
| 727 | BOMB; |
| 728 | } |
| 729 | thisFree = !is_inuse_bszW(b_bszW); |
| 730 | if (thisFree && lastWasFree) { |
| 731 | VG_(printf)( "mallocSanityCheck: sb %p, block %d (bszW %d): " |
| 732 | "UNMERGED FREES\n", |
| 733 | sb, i, b_bszW ); |
| 734 | BOMB; |
| 735 | } |
| 736 | lastWasFree = thisFree; |
| 737 | if (thisFree) blockctr_sb_free++; |
| 738 | if (!thisFree) |
| 739 | arena_bytes_on_loan += sizeof(Word) * bszW_to_pszW(a, b_bszW); |
| 740 | i += mk_plain_bszW(b_bszW); |
| 741 | } |
| 742 | if (i > sb->n_payload_words) { |
| 743 | VG_(printf)( "mallocSanityCheck: sb %p: last block " |
| 744 | "overshoots end\n", sb); |
| 745 | BOMB; |
| 746 | } |
| 747 | sb = sb->next; |
| 748 | } |
| 749 | |
| 750 | if (arena_bytes_on_loan != a->bytes_on_loan) { |
| 751 | VG_(printf)( |
| 752 | "mallocSanityCheck: a->bytes_on_loan %d, " |
| 753 | "arena_bytes_on_loan %d: " |
| 754 | "MISMATCH\n", a->bytes_on_loan, arena_bytes_on_loan); |
| 755 | ppSuperblocks(a); |
| 756 | BOMB; |
| 757 | } |
| 758 | |
| 759 | /* Second, traverse each list, checking that the back pointers make |
| 760 | sense, counting blocks encountered, and checking that each block |
| 761 | is an appropriate size for this list. */ |
| 762 | blockctr_li = 0; |
| 763 | for (listno = 0; listno < VG_N_MALLOC_LISTS; listno++) { |
| 764 | list_min_pszW = listNo_to_pszW_min(listno); |
| 765 | list_max_pszW = listNo_to_pszW_max(listno); |
| 766 | b = a->freelist[listno]; |
| 767 | if (b == NULL) continue; |
| 768 | while (True) { |
| 769 | b_prev = b; |
| 770 | b = get_next_p(b); |
| 771 | if (get_prev_p(b) != b_prev) { |
| 772 | VG_(printf)( "mallocSanityCheck: list %d at %p: " |
| 773 | "BAD LINKAGE\n", |
| 774 | listno, b ); |
| 775 | BOMB; |
| 776 | } |
| 777 | b_pszW = bszW_to_pszW(a, mk_plain_bszW(get_bszW_lo(b))); |
| 778 | if (b_pszW < list_min_pszW || b_pszW > list_max_pszW) { |
| 779 | VG_(printf)( |
| 780 | "mallocSanityCheck: list %d at %p: " |
| 781 | "WRONG CHAIN SIZE %d (%d, %d)\n", |
| 782 | listno, b, b_pszW, list_min_pszW, list_max_pszW ); |
| 783 | BOMB; |
| 784 | } |
| 785 | blockctr_li++; |
| 786 | if (b == a->freelist[listno]) break; |
| 787 | } |
| 788 | } |
| 789 | |
| 790 | if (blockctr_sb_free != blockctr_li) { |
| 791 | VG_(printf)( |
| 792 | "mallocSanityCheck: BLOCK COUNT MISMATCH " |
| 793 | "(via sbs %d, via lists %d)\n", |
| 794 | blockctr_sb_free, blockctr_li ); |
| 795 | ppSuperblocks(a); |
| 796 | BOMB; |
| 797 | } |
| 798 | |
| 799 | VG_(message)(Vg_DebugMsg, |
| 800 | "mSC [%s]: %2d sbs, %5d tot bs, %4d/%-4d free bs, " |
| 801 | "%2d lists, %7d mmap, %7d loan", |
| 802 | a->name, |
| 803 | superblockctr, |
| 804 | blockctr_sb, blockctr_sb_free, blockctr_li, |
| 805 | VG_N_MALLOC_LISTS, |
| 806 | a->bytes_mmaped, a->bytes_on_loan); |
| 807 | # undef BOMB |
| 808 | } |
| 809 | |
| 810 | |
| 811 | void VG_(mallocSanityCheckAll) ( void ) |
| 812 | { |
| 813 | Int i; |
| 814 | for (i = 0; i < VG_N_ARENAS; i++) |
| 815 | VG_(mallocSanityCheckArena) ( i ); |
| 816 | } |
| 817 | |
| 818 | |
| 819 | /* Really, this isn't the right place for this. Nevertheless: find |
| 820 | out if an arena is empty -- currently has no bytes on loan. This |
| 821 | is useful for checking for memory leaks (of valgrind, not the |
| 822 | client.) |
| 823 | */ |
| 824 | Bool VG_(is_empty_arena) ( ArenaId aid ) |
| 825 | { |
| 826 | Arena* a; |
| 827 | Superblock* sb; |
| 828 | WordF* b; |
| 829 | Int b_bszW; |
| 830 | ensure_mm_init(); |
| 831 | a = arenaId_to_ArenaP(aid); |
| 832 | for (sb = a->sblocks; sb != NULL; sb = sb->next) { |
| 833 | /* If the superblock is empty, it should contain a single free |
| 834 | block, of the right size. */ |
| 835 | b = &(sb->payload_words[0]); |
| 836 | b_bszW = get_bszW_lo(b); |
| 837 | if (is_inuse_bszW(b_bszW)) return False; |
| 838 | if (mk_plain_bszW(b_bszW) != sb->n_payload_words) return False; |
| 839 | /* So this block is not in use and is of the right size. Keep |
| 840 | going. */ |
| 841 | } |
| 842 | return True; |
| 843 | } |
| 844 | |
| 845 | |
| 846 | /*------------------------------------------------------------*/ |
| 847 | /*--- Externally-visible functions. ---*/ |
| 848 | /*------------------------------------------------------------*/ |
| 849 | |
| 850 | void* VG_(malloc) ( ArenaId aid, Int req_pszB ) |
| 851 | { |
| 852 | Int req_pszW, req_bszW, frag_bszW, b_bszW, lno; |
| 853 | Superblock* new_sb; |
| 854 | Word* b; |
| 855 | Arena* a; |
| 856 | |
| 857 | VGP_PUSHCC(VgpMalloc); |
| 858 | |
| 859 | ensure_mm_init(); |
| 860 | a = arenaId_to_ArenaP(aid); |
| 861 | |
| 862 | vg_assert(req_pszB >= 0); |
| 863 | vg_assert(req_pszB < 0x7FFFFFF0); |
| 864 | |
| 865 | req_pszW = (req_pszB + VKI_BYTES_PER_WORD - 1) / VKI_BYTES_PER_WORD; |
| 866 | |
| 867 | /* Keep gcc -O happy: */ |
| 868 | b = NULL; |
| 869 | |
| 870 | /* Start searching at this list. */ |
| 871 | lno = pszW_to_listNo(req_pszW); |
| 872 | |
| 873 | /* This loop finds a list which has a block big enough, or sets |
| 874 | req_listno to N_LISTS if no such block exists. */ |
| 875 | while (True) { |
| 876 | if (lno == VG_N_MALLOC_LISTS) break; |
| 877 | /* If this list is empty, try the next one. */ |
| 878 | if (a->freelist[lno] == NULL) { |
| 879 | lno++; |
| 880 | continue; |
| 881 | } |
| 882 | /* Scan a->list[lno] to find a big-enough chunk. */ |
| 883 | b = a->freelist[lno]; |
| 884 | b_bszW = mk_plain_bszW(get_bszW_lo(b)); |
| 885 | while (True) { |
| 886 | if (bszW_to_pszW(a, b_bszW) >= req_pszW) break; |
| 887 | b = get_next_p(b); |
| 888 | b_bszW = mk_plain_bszW(get_bszW_lo(b)); |
| 889 | if (b == a->freelist[lno]) break; |
| 890 | } |
| 891 | if (bszW_to_pszW(a, b_bszW) >= req_pszW) break; |
| 892 | /* No luck? Try a larger list. */ |
| 893 | lno++; |
| 894 | } |
| 895 | |
| 896 | /* Either lno < VG_N_MALLOC_LISTS and b points to the selected |
| 897 | block, or lno == VG_N_MALLOC_LISTS, and we have to allocate a |
| 898 | new superblock. */ |
| 899 | |
| 900 | if (lno == VG_N_MALLOC_LISTS) { |
| 901 | req_bszW = pszW_to_bszW(a, req_pszW); |
| 902 | new_sb = newSuperblock(a, req_bszW); |
| 903 | vg_assert(new_sb != NULL); |
| 904 | new_sb->next = a->sblocks; |
| 905 | a->sblocks = new_sb; |
| 906 | b = &(new_sb->payload_words[0]); |
| 907 | lno = pszW_to_listNo(bszW_to_pszW(a, new_sb->n_payload_words)); |
| 908 | mkFreeBlock ( a, b, new_sb->n_payload_words, lno); |
| 909 | } |
| 910 | |
| 911 | /* Ok, we can allocate from b, which lives in list req_listno. */ |
| 912 | vg_assert(b != NULL); |
| 913 | vg_assert(lno >= 0 && lno < VG_N_MALLOC_LISTS); |
| 914 | vg_assert(a->freelist[lno] != NULL); |
| 915 | b_bszW = mk_plain_bszW(get_bszW_lo(b)); |
| 916 | req_bszW = pszW_to_bszW(a, req_pszW); |
| 917 | /* req_bszW is the size of the block we are after. b_bszW is the |
| 918 | size of what we've actually got. */ |
| 919 | vg_assert(b_bszW >= req_bszW); |
| 920 | |
| 921 | /* Could we split this block and still get a useful fragment? |
| 922 | Where "useful" means that the payload size of the frag is at |
| 923 | least one word. */ |
| 924 | frag_bszW = b_bszW - req_bszW; |
| 925 | if (frag_bszW > overhead_szW(a)) { |
| 926 | splitChunk(a, b, lno, req_bszW); |
| 927 | } else { |
| 928 | /* No, mark as in use and use as-is. */ |
| 929 | unlinkBlock(a, b, lno); |
| 930 | /* |
| 931 | set_bszW_lo(b, mk_inuse_bszW(b_bszW)); |
| 932 | set_bszW_hi(b, mk_inuse_bszW(b_bszW)); |
| 933 | */ |
| 934 | mkInuseBlock(a, b, b_bszW); |
| 935 | } |
| 936 | vg_assert(req_bszW <= mk_plain_bszW(get_bszW_lo(b))); |
| 937 | |
| 938 | a->bytes_on_loan |
| 939 | += sizeof(Word) |
| 940 | * bszW_to_pszW(a, mk_plain_bszW(get_bszW_lo(b))); |
| 941 | if (a->bytes_on_loan > a->bytes_on_loan_max) |
| 942 | a->bytes_on_loan_max = a->bytes_on_loan; |
| 943 | |
| 944 | # ifdef DEBUG_MALLOC |
| 945 | VG_(mallocSanityCheckArena)(aid); |
| 946 | # endif |
| 947 | |
| 948 | VGP_POPCC; |
| 949 | return first_to_payload(a, b); |
| 950 | } |
| 951 | |
| 952 | |
| 953 | void VG_(free) ( ArenaId aid, void* ptr ) |
| 954 | { |
| 955 | Superblock* sb; |
| 956 | UInt* sb_payl_firstw; |
| 957 | UInt* sb_payl_lastw; |
| 958 | UInt* other; |
| 959 | UInt* ch; |
| 960 | Int ch_bszW, ch_pszW, other_bszW, ch_listno; |
| 961 | Arena* a; |
| 962 | |
| 963 | VGP_PUSHCC(VgpMalloc); |
| 964 | |
| 965 | ensure_mm_init(); |
| 966 | a = arenaId_to_ArenaP(aid); |
| 967 | |
| 968 | if (ptr == NULL) return; |
| 969 | |
| 970 | ch = payload_to_first(a, ptr); |
| 971 | |
| 972 | # ifdef DEBUG_MALLOC |
| 973 | vg_assert(blockSane(a,ch)); |
| 974 | # endif |
| 975 | |
| 976 | a->bytes_on_loan |
| 977 | -= sizeof(Word) |
| 978 | * bszW_to_pszW(a, mk_plain_bszW(get_bszW_lo(ch))); |
| 979 | |
| 980 | sb = findSb( a, ch ); |
| 981 | sb_payl_firstw = &(sb->payload_words[0]); |
| 982 | sb_payl_lastw = &(sb->payload_words[sb->n_payload_words-1]); |
| 983 | |
| 984 | /* Put this chunk back on a list somewhere. */ |
| 985 | ch_bszW = get_bszW_lo(ch); |
| 986 | ch_pszW = bszW_to_pszW(a, ch_bszW); |
| 987 | ch_listno = pszW_to_listNo(ch_pszW); |
| 988 | mkFreeBlock( a, ch, ch_bszW, ch_listno ); |
| 989 | |
| 990 | /* See if this block can be merged with the following one. */ |
| 991 | other = ch + ch_bszW; |
| 992 | /* overhead_szW(a) is the smallest possible bszW for this arena. |
| 993 | So the nearest possible end to the block beginning at other is |
| 994 | other+overhead_szW(a)-1. Hence the test below. */ |
| 995 | if (other+overhead_szW(a)-1 <= sb_payl_lastw) { |
| 996 | other_bszW = get_bszW_lo(other); |
| 997 | if (!is_inuse_bszW(other_bszW)) { |
| 998 | /* VG_(printf)( "merge-successor\n"); */ |
| 999 | other_bszW = mk_plain_bszW(other_bszW); |
| 1000 | # ifdef DEBUG_MALLOC |
| 1001 | vg_assert(blockSane(a, other)); |
| 1002 | # endif |
| 1003 | unlinkBlock( a, ch, ch_listno ); |
| 1004 | unlinkBlock( a, other, pszW_to_listNo(bszW_to_pszW(a,other_bszW)) ); |
| 1005 | ch_bszW += other_bszW; |
| 1006 | ch_listno = pszW_to_listNo(bszW_to_pszW(a, ch_bszW)); |
| 1007 | mkFreeBlock( a, ch, ch_bszW, ch_listno ); |
| 1008 | } |
| 1009 | } |
| 1010 | |
| 1011 | /* See if this block can be merged with its predecessor. */ |
| 1012 | if (ch-overhead_szW(a) >= sb_payl_firstw) { |
| 1013 | other_bszW = get_bszW_hi_from_last_word( ch-1 ); |
| 1014 | if (!is_inuse_bszW(other_bszW)) { |
| 1015 | /* VG_(printf)( "merge-predecessor\n"); */ |
| 1016 | other = last_to_first( ch-1 ); |
| 1017 | other_bszW = mk_plain_bszW(other_bszW); |
| 1018 | unlinkBlock( a, ch, ch_listno ); |
| 1019 | unlinkBlock( a, other, pszW_to_listNo(bszW_to_pszW(a, other_bszW)) ); |
| 1020 | ch = other; |
| 1021 | ch_bszW += other_bszW; |
| 1022 | ch_listno = pszW_to_listNo(bszW_to_pszW(a, ch_bszW)); |
| 1023 | mkFreeBlock( a, ch, ch_bszW, ch_listno ); |
| 1024 | } |
| 1025 | } |
| 1026 | |
| 1027 | # ifdef DEBUG_MALLOC |
| 1028 | VG_(mallocSanityCheckArena)(aid); |
| 1029 | # endif |
| 1030 | |
| 1031 | VGP_POPCC; |
| 1032 | } |
| 1033 | |
| 1034 | |
| 1035 | /* |
| 1036 | The idea for malloc_aligned() is to allocate a big block, base, and |
| 1037 | then split it into two parts: frag, which is returned to the the |
| 1038 | free pool, and align, which is the bit we're really after. Here's |
| 1039 | a picture. L and H denote the block lower and upper overheads, in |
| 1040 | words. The details are gruesome. Note it is slightly complicated |
| 1041 | because the initial request to generate base may return a bigger |
| 1042 | block than we asked for, so it is important to distinguish the base |
| 1043 | request size and the base actual size. |
| 1044 | |
| 1045 | frag_b align_b |
| 1046 | | | |
| 1047 | | frag_p | align_p |
| 1048 | | | | | |
| 1049 | v v v v |
| 1050 | |
| 1051 | +---+ +---+---+ +---+ |
| 1052 | | L |----------------| H | L |---------------| H | |
| 1053 | +---+ +---+---+ +---+ |
| 1054 | |
| 1055 | ^ ^ ^ |
| 1056 | | | : |
| 1057 | | base_p this addr must be aligned |
| 1058 | | |
| 1059 | base_b |
| 1060 | |
| 1061 | . . . . . . . |
| 1062 | <------ frag_bszW -------> . . . |
| 1063 | . <------------- base_pszW_act -----------> . |
| 1064 | . . . . . . . |
| 1065 | |
| 1066 | */ |
| 1067 | void* VG_(malloc_aligned) ( ArenaId aid, Int req_alignB, Int req_pszB ) |
| 1068 | { |
| 1069 | Int req_alignW, req_pszW, base_pszW_req, base_pszW_act, frag_bszW; |
| 1070 | Word *base_b, *base_p, *align_p; |
| 1071 | UInt saved_bytes_on_loan; |
| 1072 | Arena* a; |
| 1073 | |
| 1074 | ensure_mm_init(); |
| 1075 | a = arenaId_to_ArenaP(aid); |
| 1076 | |
| 1077 | vg_assert(req_pszB >= 0); |
| 1078 | vg_assert(req_pszB < 0x7FFFFFF0); |
| 1079 | |
| 1080 | /* Check that the requested alignment seems reasonable; that is, is |
| 1081 | a power of 2. There must be a better way to do this. What is |
| 1082 | it? */ |
| 1083 | switch (req_alignB) { |
sewardj | c76be29 | 2002-04-24 20:32:50 +0000 | [diff] [blame^] | 1084 | case 4: |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1085 | case 8: case 16: case 32: case 64: case 128: case 256: |
| 1086 | case 512: case 1024: case 2048: case 4096: case 8192: |
| 1087 | case 16384: case 32768: case 65536: case 131072: |
| 1088 | case 1048576: |
| 1089 | /* can't be bothered to calculate larger ones */ |
| 1090 | break; |
| 1091 | default: |
| 1092 | VG_(printf)("vg_malloc_aligned(%p, %d, %d)\nbad alignment request", |
| 1093 | a, req_pszB, req_alignB ); |
| 1094 | VG_(panic)("vg_malloc_aligned"); |
| 1095 | /*NOTREACHED*/ |
| 1096 | } |
| 1097 | |
| 1098 | /* Required alignment, in words. Since it's constrained to be a |
| 1099 | power of 2 >= word size, no need to align the alignment. Still, |
| 1100 | we check. */ |
| 1101 | req_alignW = req_alignB / VKI_BYTES_PER_WORD; |
| 1102 | vg_assert(req_alignB == req_alignW * VKI_BYTES_PER_WORD); |
| 1103 | |
| 1104 | /* Required payload size for the aligned chunk. */ |
| 1105 | req_pszW = (req_pszB + VKI_BYTES_PER_WORD - 1) / VKI_BYTES_PER_WORD; |
| 1106 | |
| 1107 | /* Payload size to request for the big block that we will split |
| 1108 | up. */ |
| 1109 | base_pszW_req = req_pszW + overhead_szW(a) + req_alignW; |
| 1110 | |
| 1111 | /* Payload ptr for the block we are going to split. Note this |
| 1112 | changes a->bytes_on_loan; we save and restore it ourselves. */ |
| 1113 | saved_bytes_on_loan = a->bytes_on_loan; |
| 1114 | base_p = VG_(malloc) ( aid, base_pszW_req * VKI_BYTES_PER_WORD ); |
| 1115 | a->bytes_on_loan = saved_bytes_on_loan; |
| 1116 | |
| 1117 | /* Block ptr for the block we are going to split. */ |
| 1118 | base_b = payload_to_first ( a, base_p ); |
| 1119 | |
| 1120 | /* Pointer to the payload of the aligned block we are going to |
| 1121 | return. This has to be suitably aligned. */ |
| 1122 | align_p = align_upwards ( base_b + 2 * overhead_szW_lo(a) |
| 1123 | + overhead_szW_hi(a), |
| 1124 | req_alignB ); |
| 1125 | |
| 1126 | /* The block size of the fragment we will create. This must be big |
| 1127 | enough to actually create a fragment. */ |
| 1128 | frag_bszW = align_p - overhead_szW_lo(a) - base_b; |
| 1129 | vg_assert(frag_bszW >= overhead_szW(a)); |
| 1130 | |
| 1131 | /* The actual payload size of the block we are going to split. */ |
| 1132 | base_pszW_act = bszW_to_pszW(a, mk_plain_bszW(get_bszW_lo(base_b))); |
| 1133 | |
| 1134 | /* Create the fragment block, and put it back on the relevant free |
| 1135 | list. */ |
| 1136 | mkFreeBlock ( a, base_b, frag_bszW, |
| 1137 | pszW_to_listNo(bszW_to_pszW(a, frag_bszW)) ); |
| 1138 | |
| 1139 | /* Create the aligned block. */ |
| 1140 | mkInuseBlock ( a, |
| 1141 | align_p - overhead_szW_lo(a), |
| 1142 | base_p + base_pszW_act |
| 1143 | + overhead_szW_hi(a) |
| 1144 | - (align_p - overhead_szW_lo(a)) ); |
| 1145 | |
| 1146 | /* Final sanity checks. */ |
| 1147 | vg_assert(( (UInt)align_p % req_alignB) == 0); |
| 1148 | |
| 1149 | vg_assert(is_inuse_bszW(get_bszW_lo(payload_to_first(a, align_p)))); |
| 1150 | |
| 1151 | vg_assert(req_pszW |
| 1152 | <= |
| 1153 | bszW_to_pszW(a, mk_plain_bszW(get_bszW_lo( |
| 1154 | payload_to_first(a, align_p)))) |
| 1155 | ); |
| 1156 | |
| 1157 | a->bytes_on_loan |
| 1158 | += sizeof(Word) |
| 1159 | * bszW_to_pszW(a, mk_plain_bszW(get_bszW_lo( |
| 1160 | payload_to_first(a, align_p)))); |
| 1161 | if (a->bytes_on_loan > a->bytes_on_loan_max) |
| 1162 | a->bytes_on_loan_max = a->bytes_on_loan; |
| 1163 | |
| 1164 | # ifdef DEBUG_MALLOC |
| 1165 | VG_(mallocSanityCheckArena)(aid); |
| 1166 | # endif |
| 1167 | |
| 1168 | return align_p; |
| 1169 | } |
| 1170 | |
| 1171 | |
| 1172 | /*------------------------------------------------------------*/ |
| 1173 | /*--- Services layered on top of malloc/free. ---*/ |
| 1174 | /*------------------------------------------------------------*/ |
| 1175 | |
| 1176 | void* VG_(calloc) ( ArenaId aid, Int nmemb, Int nbytes ) |
| 1177 | { |
| 1178 | Int i, size; |
| 1179 | UChar* p; |
| 1180 | size = nmemb * nbytes; |
| 1181 | vg_assert(size > 0); |
| 1182 | p = VG_(malloc) ( aid, size ); |
| 1183 | for (i = 0; i < size; i++) p[i] = 0; |
| 1184 | return p; |
| 1185 | } |
| 1186 | |
| 1187 | |
| 1188 | void* VG_(realloc) ( ArenaId aid, void* ptr, Int req_pszB ) |
| 1189 | { |
| 1190 | Arena* a; |
| 1191 | Int old_bszW, old_pszW, old_pszB, i; |
| 1192 | UChar *p_old, *p_new; |
| 1193 | UInt* ch; |
| 1194 | |
| 1195 | ensure_mm_init(); |
| 1196 | a = arenaId_to_ArenaP(aid); |
| 1197 | |
| 1198 | vg_assert(req_pszB >= 0); |
| 1199 | vg_assert(req_pszB < 0x7FFFFFF0); |
| 1200 | |
| 1201 | ch = payload_to_first(a, ptr); |
| 1202 | vg_assert(blockSane(a, ch)); |
| 1203 | |
| 1204 | old_bszW = get_bszW_lo(ch); |
| 1205 | vg_assert(is_inuse_bszW(old_bszW)); |
| 1206 | old_bszW = mk_plain_bszW(old_bszW); |
| 1207 | old_pszW = bszW_to_pszW(a, old_bszW); |
| 1208 | old_pszB = old_pszW * VKI_BYTES_PER_WORD; |
| 1209 | |
| 1210 | if (req_pszB <= old_pszB) return ptr; |
| 1211 | |
| 1212 | p_new = VG_(malloc) ( aid, req_pszB ); |
| 1213 | p_old = (UChar*)ptr; |
| 1214 | for (i = 0; i < old_pszB; i++) |
| 1215 | p_new[i] = p_old[i]; |
| 1216 | |
| 1217 | VG_(free)(aid, p_old); |
| 1218 | return p_new; |
| 1219 | } |
| 1220 | |
| 1221 | |
| 1222 | /*------------------------------------------------------------*/ |
| 1223 | /*--- The original test driver machinery. ---*/ |
| 1224 | /*------------------------------------------------------------*/ |
| 1225 | |
| 1226 | #if 0 |
| 1227 | |
| 1228 | #if 1 |
| 1229 | #define N_TEST_TRANSACTIONS 100000000 |
| 1230 | #define N_TEST_ARR 200000 |
| 1231 | #define M_TEST_MALLOC 1000 |
| 1232 | #else |
| 1233 | #define N_TEST_TRANSACTIONS 500000 |
| 1234 | #define N_TEST_ARR 30000 |
| 1235 | #define M_TEST_MALLOC 500 |
| 1236 | #endif |
| 1237 | |
| 1238 | |
| 1239 | void* test_arr[N_TEST_ARR]; |
| 1240 | |
| 1241 | int main ( int argc, char** argv ) |
| 1242 | { |
| 1243 | Int i, j, k, nbytes, qq; |
| 1244 | unsigned char* chp; |
| 1245 | Arena* a = &arena[VG_AR_PRIVATE]; |
| 1246 | srandom(1); |
| 1247 | for (i = 0; i < N_TEST_ARR; i++) |
| 1248 | test_arr[i] = NULL; |
| 1249 | |
| 1250 | for (i = 0; i < N_TEST_TRANSACTIONS; i++) { |
| 1251 | if (i % 50000 == 0) mallocSanityCheck(a); |
| 1252 | j = random() % N_TEST_ARR; |
| 1253 | if (test_arr[j]) { |
| 1254 | vg_free(a, test_arr[j]); |
| 1255 | test_arr[j] = NULL; |
| 1256 | } else { |
| 1257 | nbytes = 1 + random() % M_TEST_MALLOC; |
| 1258 | qq = random()%64; |
| 1259 | if (qq == 32) |
| 1260 | nbytes *= 17; |
| 1261 | else if (qq == 33) |
| 1262 | nbytes = 0; |
| 1263 | test_arr[j] |
| 1264 | = (i % 17) == 0 |
| 1265 | ? vg_memalign(a, nbytes, 1<< (3+(random()%10))) |
| 1266 | : vg_malloc( a, nbytes ); |
| 1267 | chp = test_arr[j]; |
| 1268 | for (k = 0; k < nbytes; k++) |
| 1269 | chp[k] = (unsigned char)(k + 99); |
| 1270 | } |
| 1271 | } |
| 1272 | |
| 1273 | |
| 1274 | for (i = 0; i < N_TEST_ARR; i++) { |
| 1275 | if (test_arr[i]) { |
| 1276 | vg_free(a, test_arr[i]); |
| 1277 | test_arr[i] = NULL; |
| 1278 | } |
| 1279 | } |
| 1280 | mallocSanityCheck(a); |
| 1281 | |
| 1282 | fprintf(stderr, "ALL DONE\n"); |
| 1283 | |
| 1284 | show_arena_stats(a); |
| 1285 | fprintf(stderr, "%d max useful, %d bytes mmap'd (%4.1f%%), %d useful\n", |
| 1286 | a->bytes_on_loan_max, |
| 1287 | a->bytes_mmaped, |
| 1288 | 100.0 * (double)a->bytes_on_loan_max / (double)a->bytes_mmaped, |
| 1289 | a->bytes_on_loan ); |
| 1290 | |
| 1291 | return 0; |
| 1292 | } |
| 1293 | #endif /* 0 */ |
| 1294 | |
| 1295 | |
| 1296 | /*--------------------------------------------------------------------*/ |
| 1297 | /*--- end vg_malloc2.c ---*/ |
| 1298 | /*--------------------------------------------------------------------*/ |