1 /* malloc.c 2 * 3 */ 4 5 /* 6 * 'The Chamber of Records,' said Gimli. 'I guess that is where we now stand.' 7 * 8 * [p.321 of _The Lord of the Rings_, II/v: "The Bridge of Khazad-Dûm"] 9 */ 10 11 /* This file contains Perl's own implementation of the malloc library. 12 * It is used if Configure decides that, on your platform, Perl's 13 * version is better than the OS's, or if you give Configure the 14 * -Dusemymalloc command-line option. 15 */ 16 17 /* 18 Here are some notes on configuring Perl's malloc. 19 20 There are two macros which serve as bulk disablers of advanced 21 features of this malloc: NO_FANCY_MALLOC, PLAIN_MALLOC (undef by 22 default). Look in the list of default values below to understand 23 their exact effect. Defining NO_FANCY_MALLOC returns malloc.c to the 24 state of the malloc in Perl 5.004. Additionally defining PLAIN_MALLOC 25 returns it to the state as of Perl 5.000. 26 27 Note that some of the settings below may be ignored in the code based 28 on values of other macros. The PERL_CORE symbol is only defined when 29 perl itself is being compiled (so malloc can make some assumptions 30 about perl's facilities being available to it). 31 32 Each config option has a short description, followed by its name, 33 default value, and a comment about the default (if applicable). Some 34 options take a precise value, while the others are just boolean. 35 The boolean ones are listed first. 36 37 # Read configuration settings from malloc_cfg.h 38 HAVE_MALLOC_CFG_H undef 39 40 # Enable code for an emergency memory pool in $^M. See perlvar.pod 41 # for a description of $^M. 42 PERL_EMERGENCY_SBRK !PLAIN_MALLOC 43 44 # Enable code for printing memory statistics. 45 DEBUGGING_MSTATS !PLAIN_MALLOC 46 47 # Move allocation info for small buckets into separate areas. 48 # Memory optimization (especially for small allocations, of the 49 # less than 64 bytes). Since perl usually makes a large number 50 # of small allocations, this is usually a win. 51 PACK_MALLOC (!PLAIN_MALLOC && !RCHECK) 52 53 # Add one page to big powers of two when calculating bucket size. 54 # This is targeted at big allocations, as are common in image 55 # processing. 56 TWO_POT_OPTIMIZE !PLAIN_MALLOC 57 58 # Use intermediate bucket sizes between powers-of-two. This is 59 # generally a memory optimization, and a (small) speed pessimization. 60 BUCKETS_ROOT2 !NO_FANCY_MALLOC 61 62 # Do not check small deallocations for bad free(). Memory 63 # and speed optimization, error reporting pessimization. 64 IGNORE_SMALL_BAD_FREE (!NO_FANCY_MALLOC && !RCHECK) 65 66 # Use table lookup to decide in which bucket a given allocation will go. 67 SMALL_BUCKET_VIA_TABLE !NO_FANCY_MALLOC 68 69 # Use a perl-defined sbrk() instead of the (presumably broken or 70 # missing) system-supplied sbrk(). 71 USE_PERL_SBRK undef 72 73 # Use system malloc() (or calloc() etc.) to emulate sbrk(). Normally 74 # only used with broken sbrk()s. 75 PERL_SBRK_VIA_MALLOC undef 76 77 # Which allocator to use if PERL_SBRK_VIA_MALLOC 78 SYSTEM_ALLOC(a) malloc(a) 79 80 # Minimal alignment (in bytes, should be a power of 2) of SYSTEM_ALLOC 81 SYSTEM_ALLOC_ALIGNMENT MEM_ALIGNBYTES 82 83 # Disable memory overwrite checking with DEBUGGING. Memory and speed 84 # optimization, error reporting pessimization. 85 NO_RCHECK undef 86 87 # Enable memory overwrite checking with DEBUGGING. Memory and speed 88 # pessimization, error reporting optimization 89 RCHECK (DEBUGGING && !NO_RCHECK) 90 91 # Do not overwrite uninit areas with DEBUGGING. Speed 92 # optimization, error reporting pessimization 93 NO_MFILL undef 94 95 # Overwrite uninit areas with DEBUGGING. Speed 96 # pessimization, error reporting optimization 97 MALLOC_FILL (DEBUGGING && !NO_RCHECK && !NO_MFILL) 98 99 # Do not check overwritten uninit areas with DEBUGGING. Speed 100 # optimization, error reporting pessimization 101 NO_FILL_CHECK undef 102 103 # Check overwritten uninit areas with DEBUGGING. Speed 104 # pessimization, error reporting optimization 105 MALLOC_FILL_CHECK (DEBUGGING && !NO_RCHECK && !NO_FILL_CHECK) 106 107 # Failed allocations bigger than this size croak (if 108 # PERL_EMERGENCY_SBRK is enabled) without touching $^M. See 109 # perlvar.pod for a description of $^M. 110 BIG_SIZE (1<<16) # 64K 111 112 # Starting from this power of two, add an extra page to the 113 # size of the bucket. This enables optimized allocations of sizes 114 # close to powers of 2. Note that the value is indexed at 0. 115 FIRST_BIG_POW2 15 # 32K, 16K is used too often 116 117 # Estimate of minimal memory footprint. malloc uses this value to 118 # request the most reasonable largest blocks of memory from the system. 119 FIRST_SBRK (48*1024) 120 121 # Round up sbrk()s to multiples of this. 122 MIN_SBRK 2048 123 124 # Round up sbrk()s to multiples of this percent of footprint. 125 MIN_SBRK_FRAC 3 126 127 # Round up sbrk()s to multiples of this multiple of 1/1000 of footprint. 128 MIN_SBRK_FRAC1000 (10 * MIN_SBRK_FRAC) 129 130 # Add this much memory to big powers of two to get the bucket size. 131 PERL_PAGESIZE 4096 132 133 # This many sbrk() discontinuities should be tolerated even 134 # from the start without deciding that sbrk() is usually 135 # discontinuous. 136 SBRK_ALLOW_FAILURES 3 137 138 # This many continuous sbrk()s compensate for one discontinuous one. 139 SBRK_FAILURE_PRICE 50 140 141 # Some configurations may ask for 12-byte-or-so allocations which 142 # require 8-byte alignment (?!). In such situation one needs to 143 # define this to disable 12-byte bucket (will increase memory footprint) 144 STRICT_ALIGNMENT undef 145 146 # Do not allow configuration of runtime options at runtime 147 NO_MALLOC_DYNAMIC_CFG undef 148 149 # Do not allow configuration of runtime options via $ENV{PERL_MALLOC_OPT} 150 NO_PERL_MALLOC_ENV undef 151 152 [The variable consists of ;-separated parts of the form CODE=VALUE 153 with 1-character codes F, M, f, A, P, G, d, a, c for runtime 154 configuration of FIRST_SBRK, MIN_SBRK, MIN_SBRK_FRAC1000, 155 SBRK_ALLOW_FAILURES, SBRK_FAILURE_PRICE, sbrk_goodness, 156 filldead, fillalive, fillcheck. The last 3 are for DEBUGGING 157 build, and allow switching the tests for free()ed memory read, 158 uninit memory reads, and free()ed memory write.] 159 160 This implementation assumes that calling PerlIO_printf() does not 161 result in any memory allocation calls (used during a panic). 162 163 */ 164 165 166 #ifdef HAVE_MALLOC_CFG_H 167 # include "malloc_cfg.h" 168 #endif 169 170 #ifndef NO_FANCY_MALLOC 171 # ifndef SMALL_BUCKET_VIA_TABLE 172 # define SMALL_BUCKET_VIA_TABLE 173 # endif 174 # ifndef BUCKETS_ROOT2 175 # define BUCKETS_ROOT2 176 # endif 177 # ifndef IGNORE_SMALL_BAD_FREE 178 # define IGNORE_SMALL_BAD_FREE 179 # endif 180 #endif 181 182 #ifndef PLAIN_MALLOC /* Bulk enable features */ 183 # ifndef PACK_MALLOC 184 # define PACK_MALLOC 185 # endif 186 # ifndef TWO_POT_OPTIMIZE 187 # define TWO_POT_OPTIMIZE 188 # endif 189 # ifndef PERL_EMERGENCY_SBRK 190 # define PERL_EMERGENCY_SBRK 191 # endif 192 # ifndef DEBUGGING_MSTATS 193 # define DEBUGGING_MSTATS 194 # endif 195 #endif 196 197 #define MIN_BUC_POW2 (sizeof(void*) > 4 ? 3 : 2) /* Allow for 4-byte arena. */ 198 #define MIN_BUCKET (MIN_BUC_POW2 * BUCKETS_PER_POW2) 199 200 #if !(defined(I286) || defined(atarist)) 201 /* take 2k unless the block is bigger than that */ 202 # define LOG_OF_MIN_ARENA 11 203 #else 204 /* take 16k unless the block is bigger than that 205 (80286s like large segments!), probably good on the atari too */ 206 # define LOG_OF_MIN_ARENA 14 207 #endif 208 209 #if defined(DEBUGGING) && !defined(NO_RCHECK) 210 # define RCHECK 211 #endif 212 #if defined(DEBUGGING) && !defined(NO_RCHECK) && !defined(NO_MFILL) && !defined(MALLOC_FILL) 213 # define MALLOC_FILL 214 #endif 215 #if defined(DEBUGGING) && !defined(NO_RCHECK) && !defined(NO_FILL_CHECK) && !defined(MALLOC_FILL_CHECK) 216 # define MALLOC_FILL_CHECK 217 #endif 218 #if defined(RCHECK) && defined(IGNORE_SMALL_BAD_FREE) 219 # undef IGNORE_SMALL_BAD_FREE 220 #endif 221 /* 222 * malloc.c (Caltech) 2/21/82 223 * Chris Kingsley, kingsley@cit-20. 224 * 225 * This is a very fast storage allocator. It allocates blocks of a small 226 * number of different sizes, and keeps free lists of each size. Blocks that 227 * don't exactly fit are passed up to the next larger size. In this 228 * implementation, the available sizes are 2^n-4 (or 2^n-12) bytes long. 229 * If PACK_MALLOC is defined, small blocks are 2^n bytes long. 230 * This is designed for use in a program that uses vast quantities of memory, 231 * but bombs when it runs out. 232 * 233 * Modifications Copyright Ilya Zakharevich 1996-99. 234 * 235 * Still very quick, but much more thrifty. (Std config is 10% slower 236 * than it was, and takes 67% of old heap size for typical usage.) 237 * 238 * Allocations of small blocks are now table-driven to many different 239 * buckets. Sizes of really big buckets are increased to accommodate 240 * common size=power-of-2 blocks. Running-out-of-memory is made into 241 * an exception. Deeply configurable and thread-safe. 242 * 243 */ 244 245 #include "EXTERN.h" 246 #define PERL_IN_MALLOC_C 247 #include "perl.h" 248 #if defined(PERL_IMPLICIT_CONTEXT) 249 # define croak Perl_croak_nocontext 250 # define croak2 Perl_croak_nocontext 251 # define warn Perl_warn_nocontext 252 # define warn2 Perl_warn_nocontext 253 #else 254 # define croak2 croak 255 # define warn2 warn 256 #endif 257 #ifdef USE_ITHREADS 258 # define PERL_MAYBE_ALIVE PL_thr_key 259 #else 260 # define PERL_MAYBE_ALIVE 1 261 #endif 262 263 #ifndef MUTEX_LOCK 264 # define MUTEX_LOCK(l) 265 #endif 266 267 #ifndef MUTEX_UNLOCK 268 # define MUTEX_UNLOCK(l) 269 #endif 270 271 #ifndef MALLOC_LOCK 272 # define MALLOC_LOCK MUTEX_LOCK(&PL_malloc_mutex) 273 #endif 274 275 #ifndef MALLOC_UNLOCK 276 # define MALLOC_UNLOCK MUTEX_UNLOCK(&PL_malloc_mutex) 277 #endif 278 279 # ifndef fatalcroak /* make depend */ 280 # define fatalcroak(mess) (write(2, (mess), strlen(mess)), exit(2)) 281 # endif 282 283 #ifdef DEBUGGING 284 # undef DEBUG_m 285 # define DEBUG_m(a) \ 286 STMT_START { \ 287 if (PERL_MAYBE_ALIVE && PERL_GET_THX) { \ 288 dTHX; \ 289 if (DEBUG_m_TEST) { \ 290 PL_debug &= ~DEBUG_m_FLAG; \ 291 a; \ 292 PL_debug |= DEBUG_m_FLAG; \ 293 } \ 294 } \ 295 } STMT_END 296 #endif 297 298 #ifdef PERL_IMPLICIT_CONTEXT 299 # define PERL_IS_ALIVE aTHX 300 #else 301 # define PERL_IS_ALIVE TRUE 302 #endif 303 304 305 /* 306 * Layout of memory: 307 * ~~~~~~~~~~~~~~~~ 308 * The memory is broken into "blocks" which occupy multiples of 2K (and 309 * generally speaking, have size "close" to a power of 2). The addresses 310 * of such *unused* blocks are kept in nextf[i] with big enough i. (nextf 311 * is an array of linked lists.) (Addresses of used blocks are not known.) 312 * 313 * Moreover, since the algorithm may try to "bite" smaller blocks out 314 * of unused bigger ones, there are also regions of "irregular" size, 315 * managed separately, by a linked list chunk_chain. 316 * 317 * The third type of storage is the sbrk()ed-but-not-yet-used space, its 318 * end and size are kept in last_sbrk_top and sbrked_remains. 319 * 320 * Growing blocks "in place": 321 * ~~~~~~~~~~~~~~~~~~~~~~~~~ 322 * The address of the block with the greatest address is kept in last_op 323 * (if not known, last_op is 0). If it is known that the memory above 324 * last_op is not continuous, or contains a chunk from chunk_chain, 325 * last_op is set to 0. 326 * 327 * The chunk with address last_op may be grown by expanding into 328 * sbrk()ed-but-not-yet-used space, or trying to sbrk() more continuous 329 * memory. 330 * 331 * Management of last_op: 332 * ~~~~~~~~~~~~~~~~~~~~~ 333 * 334 * free() never changes the boundaries of blocks, so is not relevant. 335 * 336 * The only way realloc() may change the boundaries of blocks is if it 337 * grows a block "in place". However, in the case of success such a 338 * chunk is automatically last_op, and it remains last_op. In the case 339 * of failure getpages_adjacent() clears last_op. 340 * 341 * malloc() may change blocks by calling morecore() only. 342 * 343 * morecore() may create new blocks by: 344 * a) biting pieces from chunk_chain (cannot create one above last_op); 345 * b) biting a piece from an unused block (if block was last_op, this 346 * may create a chunk from chain above last_op, thus last_op is 347 * invalidated in such a case). 348 * c) biting of sbrk()ed-but-not-yet-used space. This creates 349 * a block which is last_op. 350 * d) Allocating new pages by calling getpages(); 351 * 352 * getpages() creates a new block. It marks last_op at the bottom of 353 * the chunk of memory it returns. 354 * 355 * Active pages footprint: 356 * ~~~~~~~~~~~~~~~~~~~~~~ 357 * Note that we do not need to traverse the lists in nextf[i], just take 358 * the first element of this list. However, we *need* to traverse the 359 * list in chunk_chain, but most the time it should be a very short one, 360 * so we do not step on a lot of pages we are not going to use. 361 * 362 * Flaws: 363 * ~~~~~ 364 * get_from_bigger_buckets(): forget to increment price => Quite 365 * aggressive. 366 */ 367 368 /* I don't much care whether these are defined in sys/types.h--LAW */ 369 370 #define u_char unsigned char 371 #define u_int unsigned int 372 /* 373 * I removed the definition of u_bigint which appeared to be u_bigint = UV 374 * u_bigint was only used in TWOK_MASKED and TWOK_SHIFT 375 * where I have used PTR2UV. RMB 376 */ 377 #define u_short unsigned short 378 379 /* 286 and atarist like big chunks, which gives too much overhead. */ 380 #if (defined(RCHECK) || defined(I286) || defined(atarist)) && defined(PACK_MALLOC) 381 # undef PACK_MALLOC 382 #endif 383 384 /* 385 * The description below is applicable if PACK_MALLOC is not defined. 386 * 387 * The overhead on a block is at least 4 bytes. When free, this space 388 * contains a pointer to the next free block, and the bottom two bits must 389 * be zero. When in use, the first byte is set to MAGIC, and the second 390 * byte is the size index. The remaining bytes are for alignment. 391 * If range checking is enabled and the size of the block fits 392 * in two bytes, then the top two bytes hold the size of the requested block 393 * plus the range checking words, and the header word MINUS ONE. 394 */ 395 union overhead { 396 union overhead *ov_next; /* when free */ 397 #if MEM_ALIGNBYTES > 4 398 double strut; /* alignment problems */ 399 # if MEM_ALIGNBYTES > 8 400 char sstrut[MEM_ALIGNBYTES]; /* for the sizing */ 401 # endif 402 #endif 403 struct { 404 /* 405 * Keep the ovu_index and ovu_magic in this order, having a char 406 * field first gives alignment indigestion in some systems, such as 407 * MachTen. 408 */ 409 u_char ovu_index; /* bucket # */ 410 u_char ovu_magic; /* magic number */ 411 #ifdef RCHECK 412 /* Subtract one to fit into u_short for an extra bucket */ 413 u_short ovu_size; /* block size (requested + overhead - 1) */ 414 u_int ovu_rmagic; /* range magic number */ 415 #endif 416 } ovu; 417 #define ov_magic ovu.ovu_magic 418 #define ov_index ovu.ovu_index 419 #define ov_size ovu.ovu_size 420 #define ov_rmagic ovu.ovu_rmagic 421 }; 422 423 #define MAGIC 0xff /* magic # on accounting info */ 424 #define RMAGIC 0x55555555 /* magic # on range info */ 425 #define RMAGIC_C 0x55 /* magic # on range info */ 426 427 #ifdef RCHECK 428 # define RMAGIC_SZ sizeof (u_int) /* Overhead at end of bucket */ 429 # ifdef TWO_POT_OPTIMIZE 430 # define MAX_SHORT_BUCKET (12 * BUCKETS_PER_POW2) /* size-1 fits in short */ 431 # else 432 # define MAX_SHORT_BUCKET (13 * BUCKETS_PER_POW2) 433 # endif 434 #else 435 # define RMAGIC_SZ 0 436 #endif 437 438 #if !defined(PACK_MALLOC) && defined(BUCKETS_ROOT2) 439 # undef BUCKETS_ROOT2 440 #endif 441 442 #ifdef BUCKETS_ROOT2 443 # define BUCKET_TABLE_SHIFT 2 444 # define BUCKET_POW2_SHIFT 1 445 # define BUCKETS_PER_POW2 2 446 #else 447 # define BUCKET_TABLE_SHIFT MIN_BUC_POW2 448 # define BUCKET_POW2_SHIFT 0 449 # define BUCKETS_PER_POW2 1 450 #endif 451 452 #if !defined(MEM_ALIGNBYTES) || ((MEM_ALIGNBYTES > 4) && !defined(STRICT_ALIGNMENT)) 453 /* Figure out the alignment of void*. */ 454 struct aligner { 455 char c; 456 void *p; 457 }; 458 # define ALIGN_SMALL ((int)((caddr_t)&(((struct aligner*)0)->p))) 459 #else 460 # define ALIGN_SMALL MEM_ALIGNBYTES 461 #endif 462 463 #define IF_ALIGN_8(yes,no) ((ALIGN_SMALL>4) ? (yes) : (no)) 464 465 #ifdef BUCKETS_ROOT2 466 # define MAX_BUCKET_BY_TABLE 13 467 static const u_short buck_size[MAX_BUCKET_BY_TABLE + 1] = 468 { 469 0, 0, 0, 0, 4, 4, 8, 12, 16, 24, 32, 48, 64, 80, 470 }; 471 # define BUCKET_SIZE_NO_SURPLUS(i) ((i) % 2 ? buck_size[i] : (1 << ((i) >> BUCKET_POW2_SHIFT))) 472 # define BUCKET_SIZE_REAL(i) ((i) <= MAX_BUCKET_BY_TABLE \ 473 ? buck_size[i] \ 474 : ((1 << ((i) >> BUCKET_POW2_SHIFT)) \ 475 - MEM_OVERHEAD(i) \ 476 + POW2_OPTIMIZE_SURPLUS(i))) 477 #else 478 # define BUCKET_SIZE_NO_SURPLUS(i) (1 << ((i) >> BUCKET_POW2_SHIFT)) 479 # define BUCKET_SIZE(i) (BUCKET_SIZE_NO_SURPLUS(i) + POW2_OPTIMIZE_SURPLUS(i)) 480 # define BUCKET_SIZE_REAL(i) (BUCKET_SIZE(i) - MEM_OVERHEAD(i)) 481 #endif 482 483 484 #ifdef PACK_MALLOC 485 /* In this case there are several possible layout of arenas depending 486 * on the size. Arenas are of sizes multiple to 2K, 2K-aligned, and 487 * have a size close to a power of 2. 488 * 489 * Arenas of the size >= 4K keep one chunk only. Arenas of size 2K 490 * may keep one chunk or multiple chunks. Here are the possible 491 * layouts of arenas: 492 * 493 * # One chunk only, chunksize 2^k + SOMETHING - ALIGN, k >= 11 494 * 495 * INDEX MAGIC1 UNUSED CHUNK1 496 * 497 * # Multichunk with sanity checking and chunksize 2^k-ALIGN, k>7 498 * 499 * INDEX MAGIC1 MAGIC2 MAGIC3 UNUSED CHUNK1 CHUNK2 CHUNK3 ... 500 * 501 * # Multichunk with sanity checking and size 2^k-ALIGN, k=7 502 * 503 * INDEX MAGIC1 MAGIC2 MAGIC3 UNUSED CHUNK1 UNUSED CHUNK2 CHUNK3 ... 504 * 505 * # Multichunk with sanity checking and size up to 80 506 * 507 * INDEX UNUSED MAGIC1 UNUSED MAGIC2 UNUSED ... CHUNK1 CHUNK2 CHUNK3 ... 508 * 509 * # No sanity check (usually up to 48=byte-long buckets) 510 * INDEX UNUSED CHUNK1 CHUNK2 ... 511 * 512 * Above INDEX and MAGIC are one-byte-long. Sizes of UNUSED are 513 * appropriate to keep algorithms simple and memory aligned. INDEX 514 * encodes the size of the chunk, while MAGICn encodes state (used, 515 * free or non-managed-by-us-so-it-indicates-a-bug) of CHUNKn. MAGIC 516 * is used for sanity checking purposes only. SOMETHING is 0 or 4K 517 * (to make size of big CHUNK accommodate allocations for powers of two 518 * better). 519 * 520 * [There is no need to alignment between chunks, since C rules ensure 521 * that structs which need 2^k alignment have sizeof which is 522 * divisible by 2^k. Thus as far as the last chunk is aligned at the 523 * end of the arena, and 2K-alignment does not contradict things, 524 * everything is going to be OK for sizes of chunks 2^n and 2^n + 525 * 2^k. Say, 80-bit buckets will be 16-bit aligned, and as far as we 526 * put allocations for requests in 65..80 range, all is fine. 527 * 528 * Note, however, that standard malloc() puts more strict 529 * requirements than the above C rules. Moreover, our algorithms of 530 * realloc() may break this idyll, but we suppose that realloc() does 531 * need not change alignment.] 532 * 533 * Is very important to make calculation of the offset of MAGICm as 534 * quick as possible, since it is done on each malloc()/free(). In 535 * fact it is so quick that it has quite little effect on the speed of 536 * doing malloc()/free(). [By default] We forego such calculations 537 * for small chunks, but only to save extra 3% of memory, not because 538 * of speed considerations. 539 * 540 * Here is the algorithm [which is the same for all the allocations 541 * schemes above], see OV_MAGIC(block,bucket). Let OFFSETm be the 542 * offset of the CHUNKm from the start of ARENA. Then offset of 543 * MAGICm is (OFFSET1 >> SHIFT) + ADDOFFSET. Here SHIFT and ADDOFFSET 544 * are numbers which depend on the size of the chunks only. 545 * 546 * Let as check some sanity conditions. Numbers OFFSETm>>SHIFT are 547 * different for all the chunks in the arena if 2^SHIFT is not greater 548 * than size of the chunks in the arena. MAGIC1 will not overwrite 549 * INDEX provided ADDOFFSET is >0 if OFFSET1 < 2^SHIFT. MAGIClast 550 * will not overwrite CHUNK1 if OFFSET1 > (OFFSETlast >> SHIFT) + 551 * ADDOFFSET. 552 * 553 * Make SHIFT the maximal possible (there is no point in making it 554 * smaller). Since OFFSETlast is 2K - CHUNKSIZE, above restrictions 555 * give restrictions on OFFSET1 and on ADDOFFSET. 556 * 557 * In particular, for chunks of size 2^k with k>=6 we can put 558 * ADDOFFSET to be from 0 to 2^k - 2^(11-k), and have 559 * OFFSET1==chunksize. For chunks of size 80 OFFSET1 of 2K%80=48 is 560 * large enough to have ADDOFFSET between 1 and 16 (similarly for 96, 561 * when ADDOFFSET should be 1). In particular, keeping MAGICs for 562 * these sizes gives no additional size penalty. 563 * 564 * However, for chunks of size 2^k with k<=5 this gives OFFSET1 >= 565 * ADDOFSET + 2^(11-k). Keeping ADDOFFSET 0 allows for 2^(11-k)-2^(11-2k) 566 * chunks per arena. This is smaller than 2^(11-k) - 1 which are 567 * needed if no MAGIC is kept. [In fact, having a negative ADDOFFSET 568 * would allow for slightly more buckets per arena for k=2,3.] 569 * 570 * Similarly, for chunks of size 3/2*2^k with k<=5 MAGICs would span 571 * the area up to 2^(11-k)+ADDOFFSET. For k=4 this give optimal 572 * ADDOFFSET as -7..0. For k=3 ADDOFFSET can go up to 4 (with tiny 573 * savings for negative ADDOFFSET). For k=5 ADDOFFSET can go -1..16 574 * (with no savings for negative values). 575 * 576 * In particular, keeping ADDOFFSET 0 for sizes of chunks up to 2^6 577 * leads to tiny pessimizations in case of sizes 4, 8, 12, 24, and 578 * leads to no contradictions except for size=80 (or 96.) 579 * 580 * However, it also makes sense to keep no magic for sizes 48 or less. 581 * This is what we do. In this case one needs ADDOFFSET>=1 also for 582 * chunksizes 12, 24, and 48, unless one gets one less chunk per 583 * arena. 584 * 585 * The algo of OV_MAGIC(block,bucket) keeps ADDOFFSET 0 until 586 * chunksize of 64, then makes it 1. 587 * 588 * This allows for an additional optimization: the above scheme leads 589 * to giant overheads for sizes 128 or more (one whole chunk needs to 590 * be sacrifised to keep INDEX). Instead we use chunks not of size 591 * 2^k, but of size 2^k-ALIGN. If we pack these chunks at the end of 592 * the arena, then the beginnings are still in different 2^k-long 593 * sections of the arena if k>=7 for ALIGN==4, and k>=8 if ALIGN=8. 594 * Thus for k>7 the above algo of calculating the offset of the magic 595 * will still give different answers for different chunks. And to 596 * avoid the overrun of MAGIC1 into INDEX, one needs ADDOFFSET of >=1. 597 * In the case k=7 we just move the first chunk an extra ALIGN 598 * backward inside the ARENA (this is done once per arena lifetime, 599 * thus is not a big overhead). */ 600 # define MAX_PACKED_POW2 6 601 # define MAX_PACKED (MAX_PACKED_POW2 * BUCKETS_PER_POW2 + BUCKET_POW2_SHIFT) 602 # define MAX_POW2_ALGO ((1<<(MAX_PACKED_POW2 + 1)) - M_OVERHEAD) 603 # define TWOK_MASK ((1<<LOG_OF_MIN_ARENA) - 1) 604 # define TWOK_MASKED(x) (PTR2UV(x) & ~TWOK_MASK) 605 # define TWOK_SHIFT(x) (PTR2UV(x) & TWOK_MASK) 606 # define OV_INDEXp(block) (INT2PTR(u_char*,TWOK_MASKED(block))) 607 # define OV_INDEX(block) (*OV_INDEXp(block)) 608 # define OV_MAGIC(block,bucket) (*(OV_INDEXp(block) + \ 609 (TWOK_SHIFT(block)>> \ 610 (bucket>>BUCKET_POW2_SHIFT)) + \ 611 (bucket >= MIN_NEEDS_SHIFT ? 1 : 0))) 612 /* A bucket can have a shift smaller than it size, we need to 613 shift its magic number so it will not overwrite index: */ 614 # ifdef BUCKETS_ROOT2 615 # define MIN_NEEDS_SHIFT (7*BUCKETS_PER_POW2 - 1) /* Shift 80 greater than chunk 64. */ 616 # else 617 # define MIN_NEEDS_SHIFT (7*BUCKETS_PER_POW2) /* Shift 128 greater than chunk 32. */ 618 # endif 619 # define CHUNK_SHIFT 0 620 621 /* Number of active buckets of given ordinal. */ 622 #ifdef IGNORE_SMALL_BAD_FREE 623 #define FIRST_BUCKET_WITH_CHECK (6 * BUCKETS_PER_POW2) /* 64 */ 624 # define N_BLKS(bucket) ( (bucket) < FIRST_BUCKET_WITH_CHECK \ 625 ? ((1<<LOG_OF_MIN_ARENA) - 1)/BUCKET_SIZE_NO_SURPLUS(bucket) \ 626 : n_blks[bucket] ) 627 #else 628 # define N_BLKS(bucket) n_blks[bucket] 629 #endif 630 631 static const u_short n_blks[LOG_OF_MIN_ARENA * BUCKETS_PER_POW2] = 632 { 633 # if BUCKETS_PER_POW2==1 634 0, 0, 635 (MIN_BUC_POW2==2 ? 384 : 0), 636 224, 120, 62, 31, 16, 8, 4, 2 637 # else 638 0, 0, 0, 0, 639 (MIN_BUC_POW2==2 ? 384 : 0), (MIN_BUC_POW2==2 ? 384 : 0), /* 4, 4 */ 640 224, 149, 120, 80, 62, 41, 31, 25, 16, 16, 8, 8, 4, 4, 2, 2 641 # endif 642 }; 643 644 /* Shift of the first bucket with the given ordinal inside 2K chunk. */ 645 #ifdef IGNORE_SMALL_BAD_FREE 646 # define BLK_SHIFT(bucket) ( (bucket) < FIRST_BUCKET_WITH_CHECK \ 647 ? ((1<<LOG_OF_MIN_ARENA) \ 648 - BUCKET_SIZE_NO_SURPLUS(bucket) * N_BLKS(bucket)) \ 649 : blk_shift[bucket]) 650 #else 651 # define BLK_SHIFT(bucket) blk_shift[bucket] 652 #endif 653 654 static const u_short blk_shift[LOG_OF_MIN_ARENA * BUCKETS_PER_POW2] = 655 { 656 # if BUCKETS_PER_POW2==1 657 0, 0, 658 (MIN_BUC_POW2==2 ? 512 : 0), 659 256, 128, 64, 64, /* 8 to 64 */ 660 16*sizeof(union overhead), 661 8*sizeof(union overhead), 662 4*sizeof(union overhead), 663 2*sizeof(union overhead), 664 # else 665 0, 0, 0, 0, 666 (MIN_BUC_POW2==2 ? 512 : 0), (MIN_BUC_POW2==2 ? 512 : 0), 667 256, 260, 128, 128, 64, 80, 64, 48, /* 8 to 96 */ 668 16*sizeof(union overhead), 16*sizeof(union overhead), 669 8*sizeof(union overhead), 8*sizeof(union overhead), 670 4*sizeof(union overhead), 4*sizeof(union overhead), 671 2*sizeof(union overhead), 2*sizeof(union overhead), 672 # endif 673 }; 674 675 # define NEEDED_ALIGNMENT 0x800 /* 2k boundaries */ 676 # define WANTED_ALIGNMENT 0x800 /* 2k boundaries */ 677 678 #else /* !PACK_MALLOC */ 679 680 # define OV_MAGIC(block,bucket) (block)->ov_magic 681 # define OV_INDEX(block) (block)->ov_index 682 # define CHUNK_SHIFT 1 683 # define MAX_PACKED -1 684 # define NEEDED_ALIGNMENT MEM_ALIGNBYTES 685 # define WANTED_ALIGNMENT 0x400 /* 1k boundaries */ 686 687 #endif /* !PACK_MALLOC */ 688 689 #define M_OVERHEAD (sizeof(union overhead) + RMAGIC_SZ) /* overhead at start+end */ 690 691 #ifdef PACK_MALLOC 692 # define MEM_OVERHEAD(bucket) \ 693 (bucket <= MAX_PACKED ? 0 : M_OVERHEAD) 694 # ifdef SMALL_BUCKET_VIA_TABLE 695 # define START_SHIFTS_BUCKET ((MAX_PACKED_POW2 + 1) * BUCKETS_PER_POW2) 696 # define START_SHIFT MAX_PACKED_POW2 697 # ifdef BUCKETS_ROOT2 /* Chunks of size 3*2^n. */ 698 # define SIZE_TABLE_MAX 80 699 # else 700 # define SIZE_TABLE_MAX 64 701 # endif 702 static const char bucket_of[] = 703 { 704 # ifdef BUCKETS_ROOT2 /* Chunks of size 3*2^n. */ 705 /* 0 to 15 in 4-byte increments. */ 706 (sizeof(void*) > 4 ? 6 : 5), /* 4/8, 5-th bucket for better reports */ 707 6, /* 8 */ 708 IF_ALIGN_8(8,7), 8, /* 16/12, 16 */ 709 9, 9, 10, 10, /* 24, 32 */ 710 11, 11, 11, 11, /* 48 */ 711 12, 12, 12, 12, /* 64 */ 712 13, 13, 13, 13, /* 80 */ 713 13, 13, 13, 13 /* 80 */ 714 # else /* !BUCKETS_ROOT2 */ 715 /* 0 to 15 in 4-byte increments. */ 716 (sizeof(void*) > 4 ? 3 : 2), 717 3, 718 4, 4, 719 5, 5, 5, 5, 720 6, 6, 6, 6, 721 6, 6, 6, 6 722 # endif /* !BUCKETS_ROOT2 */ 723 }; 724 # else /* !SMALL_BUCKET_VIA_TABLE */ 725 # define START_SHIFTS_BUCKET MIN_BUCKET 726 # define START_SHIFT (MIN_BUC_POW2 - 1) 727 # endif /* !SMALL_BUCKET_VIA_TABLE */ 728 #else /* !PACK_MALLOC */ 729 # define MEM_OVERHEAD(bucket) M_OVERHEAD 730 # ifdef SMALL_BUCKET_VIA_TABLE 731 # undef SMALL_BUCKET_VIA_TABLE 732 # endif 733 # define START_SHIFTS_BUCKET MIN_BUCKET 734 # define START_SHIFT (MIN_BUC_POW2 - 1) 735 #endif /* !PACK_MALLOC */ 736 737 /* 738 * Big allocations are often of the size 2^n bytes. To make them a 739 * little bit better, make blocks of size 2^n+pagesize for big n. 740 */ 741 742 #ifdef TWO_POT_OPTIMIZE 743 744 # ifndef PERL_PAGESIZE 745 # define PERL_PAGESIZE 4096 746 # endif 747 # ifndef FIRST_BIG_POW2 748 # define FIRST_BIG_POW2 15 /* 32K, 16K is used too often. */ 749 # endif 750 # define FIRST_BIG_BLOCK (1<<FIRST_BIG_POW2) 751 /* If this value or more, check against bigger blocks. */ 752 # define FIRST_BIG_BOUND (FIRST_BIG_BLOCK - M_OVERHEAD) 753 /* If less than this value, goes into 2^n-overhead-block. */ 754 # define LAST_SMALL_BOUND ((FIRST_BIG_BLOCK>>1) - M_OVERHEAD) 755 756 # define POW2_OPTIMIZE_ADJUST(nbytes) \ 757 ((nbytes >= FIRST_BIG_BOUND) ? nbytes -= PERL_PAGESIZE : 0) 758 # define POW2_OPTIMIZE_SURPLUS(bucket) \ 759 ((bucket >= FIRST_BIG_POW2 * BUCKETS_PER_POW2) ? PERL_PAGESIZE : 0) 760 761 #else /* !TWO_POT_OPTIMIZE */ 762 # define POW2_OPTIMIZE_ADJUST(nbytes) 763 # define POW2_OPTIMIZE_SURPLUS(bucket) 0 764 #endif /* !TWO_POT_OPTIMIZE */ 765 766 #ifdef HAS_64K_LIMIT 767 # define BARK_64K_LIMIT(what,nbytes,size) \ 768 if (nbytes > 0xffff) { \ 769 PerlIO_printf(PerlIO_stderr(), \ 770 "%s too large: %lx\n", what, size); \ 771 my_exit(1); \ 772 } 773 #else /* !HAS_64K_LIMIT */ 774 # define BARK_64K_LIMIT(what,nbytes,size) 775 #endif /* !HAS_64K_LIMIT */ 776 777 #ifndef MIN_SBRK 778 # define MIN_SBRK 2048 779 #endif 780 781 #ifndef FIRST_SBRK 782 # define FIRST_SBRK (48*1024) 783 #endif 784 785 /* Minimal sbrk in percents of what is already alloced. */ 786 #ifndef MIN_SBRK_FRAC 787 # define MIN_SBRK_FRAC 3 788 #endif 789 790 #ifndef SBRK_ALLOW_FAILURES 791 # define SBRK_ALLOW_FAILURES 3 792 #endif 793 794 #ifndef SBRK_FAILURE_PRICE 795 # define SBRK_FAILURE_PRICE 50 796 #endif 797 798 static void morecore (register int bucket); 799 # if defined(DEBUGGING) 800 static void botch (const char *diag, const char *s, const char *file, int line); 801 # endif 802 static void add_to_chain (void *p, MEM_SIZE size, MEM_SIZE chip); 803 static void* get_from_chain (MEM_SIZE size); 804 static void* get_from_bigger_buckets(int bucket, MEM_SIZE size); 805 static union overhead *getpages (MEM_SIZE needed, int *nblksp, int bucket); 806 static int getpages_adjacent(MEM_SIZE require); 807 808 #ifdef I_MACH_CTHREADS 809 # undef MUTEX_LOCK 810 # define MUTEX_LOCK(m) STMT_START { if (*m) mutex_lock(*m); } STMT_END 811 # undef MUTEX_UNLOCK 812 # define MUTEX_UNLOCK(m) STMT_START { if (*m) mutex_unlock(*m); } STMT_END 813 #endif 814 815 #ifndef PTRSIZE 816 # define PTRSIZE sizeof(void*) 817 #endif 818 819 #ifndef BITS_IN_PTR 820 # define BITS_IN_PTR (8*PTRSIZE) 821 #endif 822 823 /* 824 * nextf[i] is the pointer to the next free block of size 2^i. The 825 * smallest allocatable block is 8 bytes. The overhead information 826 * precedes the data area returned to the user. 827 */ 828 #define NBUCKETS (BITS_IN_PTR*BUCKETS_PER_POW2 + 1) 829 static union overhead *nextf[NBUCKETS]; 830 831 #if defined(PURIFY) && !defined(USE_PERL_SBRK) 832 # define USE_PERL_SBRK 833 #endif 834 835 #ifdef USE_PERL_SBRK 836 # define sbrk(a) Perl_sbrk(a) 837 Malloc_t Perl_sbrk (int size); 838 #else 839 # ifndef HAS_SBRK_PROTO /* <unistd.h> usually takes care of this */ 840 extern Malloc_t sbrk(int); 841 # endif 842 #endif 843 844 #ifndef MIN_SBRK_FRAC1000 /* Backward compatibility */ 845 # define MIN_SBRK_FRAC1000 (MIN_SBRK_FRAC * 10) 846 #endif 847 848 #ifndef START_EXTERN_C 849 # ifdef __cplusplus 850 # define START_EXTERN_C extern "C" { 851 # else 852 # define START_EXTERN_C 853 # endif 854 #endif 855 856 #ifndef END_EXTERN_C 857 # ifdef __cplusplus 858 # define END_EXTERN_C }; 859 # else 860 # define END_EXTERN_C 861 # endif 862 #endif 863 864 #include "malloc_ctl.h" 865 866 #ifndef NO_MALLOC_DYNAMIC_CFG 867 # define PERL_MALLOC_OPT_CHARS "FMfAPGdac" 868 869 # ifndef FILL_DEAD_DEFAULT 870 # define FILL_DEAD_DEFAULT 1 871 # endif 872 # ifndef FILL_ALIVE_DEFAULT 873 # define FILL_ALIVE_DEFAULT 1 874 # endif 875 # ifndef FILL_CHECK_DEFAULT 876 # define FILL_CHECK_DEFAULT 1 877 # endif 878 879 static IV MallocCfg[MallocCfg_last] = { 880 FIRST_SBRK, 881 MIN_SBRK, 882 MIN_SBRK_FRAC, 883 SBRK_ALLOW_FAILURES, 884 SBRK_FAILURE_PRICE, 885 SBRK_ALLOW_FAILURES * SBRK_FAILURE_PRICE, /* sbrk_goodness */ 886 FILL_DEAD_DEFAULT, /* FILL_DEAD */ 887 FILL_ALIVE_DEFAULT, /* FILL_ALIVE */ 888 FILL_CHECK_DEFAULT, /* FILL_CHECK */ 889 0, /* MallocCfg_skip_cfg_env */ 890 0, /* MallocCfg_cfg_env_read */ 891 0, /* MallocCfg_emergency_buffer_size */ 892 0, /* MallocCfg_emergency_buffer_prepared_size */ 893 0 /* MallocCfg_emergency_buffer_last_req */ 894 }; 895 IV *MallocCfg_ptr = MallocCfg; 896 897 static char* MallocCfgP[MallocCfg_last] = { 898 0, /* MallocCfgP_emergency_buffer */ 899 0, /* MallocCfgP_emergency_buffer_prepared */ 900 }; 901 char **MallocCfgP_ptr = MallocCfgP; 902 903 # undef MIN_SBRK 904 # undef FIRST_SBRK 905 # undef MIN_SBRK_FRAC1000 906 # undef SBRK_ALLOW_FAILURES 907 # undef SBRK_FAILURE_PRICE 908 909 # define MIN_SBRK MallocCfg[MallocCfg_MIN_SBRK] 910 # define FIRST_SBRK MallocCfg[MallocCfg_FIRST_SBRK] 911 # define MIN_SBRK_FRAC1000 MallocCfg[MallocCfg_MIN_SBRK_FRAC1000] 912 # define SBRK_ALLOW_FAILURES MallocCfg[MallocCfg_SBRK_ALLOW_FAILURES] 913 # define SBRK_FAILURE_PRICE MallocCfg[MallocCfg_SBRK_FAILURE_PRICE] 914 915 # define sbrk_goodness MallocCfg[MallocCfg_sbrk_goodness] 916 917 # define emergency_buffer_size MallocCfg[MallocCfg_emergency_buffer_size] 918 # define emergency_buffer_last_req MallocCfg[MallocCfg_emergency_buffer_last_req] 919 920 # define FILL_DEAD MallocCfg[MallocCfg_filldead] 921 # define FILL_ALIVE MallocCfg[MallocCfg_fillalive] 922 # define FILL_CHECK_CFG MallocCfg[MallocCfg_fillcheck] 923 # define FILL_CHECK (FILL_DEAD && FILL_CHECK_CFG) 924 925 # define emergency_buffer MallocCfgP[MallocCfgP_emergency_buffer] 926 # define emergency_buffer_prepared MallocCfgP[MallocCfgP_emergency_buffer_prepared] 927 928 #else /* defined(NO_MALLOC_DYNAMIC_CFG) */ 929 930 # define FILL_DEAD 1 931 # define FILL_ALIVE 1 932 # define FILL_CHECK 1 933 static int sbrk_goodness = SBRK_ALLOW_FAILURES * SBRK_FAILURE_PRICE; 934 935 # define NO_PERL_MALLOC_ENV 936 937 #endif 938 939 #ifdef DEBUGGING_MSTATS 940 /* 941 * nmalloc[i] is the difference between the number of mallocs and frees 942 * for a given block size. 943 */ 944 static u_int nmalloc[NBUCKETS]; 945 static u_int sbrk_slack; 946 static u_int start_slack; 947 #else /* !( defined DEBUGGING_MSTATS ) */ 948 # define sbrk_slack 0 949 #endif 950 951 static u_int goodsbrk; 952 953 #ifdef PERL_EMERGENCY_SBRK 954 955 # ifndef BIG_SIZE 956 # define BIG_SIZE (1<<16) /* 64K */ 957 # endif 958 959 # ifdef NO_MALLOC_DYNAMIC_CFG 960 static MEM_SIZE emergency_buffer_size; 961 /* 0 if the last request for more memory succeeded. 962 Otherwise the size of the failing request. */ 963 static MEM_SIZE emergency_buffer_last_req; 964 static char *emergency_buffer; 965 static char *emergency_buffer_prepared; 966 # endif 967 968 # ifndef emergency_sbrk_croak 969 # define emergency_sbrk_croak croak2 970 # endif 971 972 static char * 973 perl_get_emergency_buffer(IV *size) 974 { 975 dTHX; 976 /* First offense, give a possibility to recover by dieing. */ 977 /* No malloc involved here: */ 978 SV *sv; 979 char *pv; 980 GV **gvp = (GV**)hv_fetchs(PL_defstash, "^M", FALSE); 981 982 if (!gvp) gvp = (GV**)hv_fetchs(PL_defstash, "\015", FALSE); 983 if (!gvp || !(sv = GvSV(*gvp)) || !SvPOK(sv) 984 || (SvLEN(sv) < (1<<LOG_OF_MIN_ARENA) - M_OVERHEAD)) 985 return NULL; /* Now die die die... */ 986 /* Got it, now detach SvPV: */ 987 pv = SvPV_nolen(sv); 988 /* Check alignment: */ 989 if ((PTR2UV(pv) - sizeof(union overhead)) & (NEEDED_ALIGNMENT - 1)) { 990 PerlIO_puts(PerlIO_stderr(),"Bad alignment of $^M!\n"); 991 return NULL; /* die die die */ 992 } 993 994 SvPOK_off(sv); 995 SvPV_set(sv, NULL); 996 SvCUR_set(sv, 0); 997 SvLEN_set(sv, 0); 998 *size = malloced_size(pv) + M_OVERHEAD; 999 return pv - sizeof(union overhead); 1000 } 1001 # define PERL_GET_EMERGENCY_BUFFER(p) perl_get_emergency_buffer(p) 1002 1003 # ifndef NO_MALLOC_DYNAMIC_CFG 1004 static char * 1005 get_emergency_buffer(IV *size) 1006 { 1007 char *pv = emergency_buffer_prepared; 1008 1009 *size = MallocCfg[MallocCfg_emergency_buffer_prepared_size]; 1010 emergency_buffer_prepared = 0; 1011 MallocCfg[MallocCfg_emergency_buffer_prepared_size] = 0; 1012 return pv; 1013 } 1014 1015 /* Returns 0 on success, -1 on bad alignment, -2 if not implemented */ 1016 int 1017 set_emergency_buffer(char *b, IV size) 1018 { 1019 if (PTR2UV(b) & (NEEDED_ALIGNMENT - 1)) 1020 return -1; 1021 if (MallocCfg[MallocCfg_emergency_buffer_prepared_size]) 1022 add_to_chain((void*)emergency_buffer_prepared, 1023 MallocCfg[MallocCfg_emergency_buffer_prepared_size], 0); 1024 emergency_buffer_prepared = b; 1025 MallocCfg[MallocCfg_emergency_buffer_prepared_size] = size; 1026 return 0; 1027 } 1028 # define GET_EMERGENCY_BUFFER(p) get_emergency_buffer(p) 1029 # else /* NO_MALLOC_DYNAMIC_CFG */ 1030 # define GET_EMERGENCY_BUFFER(p) NULL 1031 int 1032 set_emergency_buffer(char *b, IV size) 1033 { 1034 return -1; 1035 } 1036 # endif 1037 1038 static Malloc_t 1039 emergency_sbrk(MEM_SIZE size) 1040 { 1041 MEM_SIZE rsize = (((size - 1)>>LOG_OF_MIN_ARENA) + 1)<<LOG_OF_MIN_ARENA; 1042 1043 if (size >= BIG_SIZE 1044 && (!emergency_buffer_last_req || 1045 (size < (MEM_SIZE)emergency_buffer_last_req))) { 1046 /* Give the possibility to recover, but avoid an infinite cycle. */ 1047 MALLOC_UNLOCK; 1048 emergency_buffer_last_req = size; 1049 emergency_sbrk_croak("Out of memory during \"large\" request for %"UVuf" bytes, total sbrk() is %"UVuf" bytes", (UV)size, (UV)(goodsbrk + sbrk_slack)); 1050 } 1051 1052 if ((MEM_SIZE)emergency_buffer_size >= rsize) { 1053 char *old = emergency_buffer; 1054 1055 emergency_buffer_size -= rsize; 1056 emergency_buffer += rsize; 1057 return old; 1058 } else { 1059 /* First offense, give a possibility to recover by dieing. */ 1060 /* No malloc involved here: */ 1061 IV Size; 1062 char *pv = GET_EMERGENCY_BUFFER(&Size); 1063 int have = 0; 1064 1065 if (emergency_buffer_size) { 1066 add_to_chain(emergency_buffer, emergency_buffer_size, 0); 1067 emergency_buffer_size = 0; 1068 emergency_buffer = NULL; 1069 have = 1; 1070 } 1071 1072 if (!pv) 1073 pv = PERL_GET_EMERGENCY_BUFFER(&Size); 1074 if (!pv) { 1075 if (have) 1076 goto do_croak; 1077 return (char *)-1; /* Now die die die... */ 1078 } 1079 1080 /* Check alignment: */ 1081 if (PTR2UV(pv) & (NEEDED_ALIGNMENT - 1)) { 1082 dTHX; 1083 1084 PerlIO_puts(PerlIO_stderr(),"Bad alignment of $^M!\n"); 1085 return (char *)-1; /* die die die */ 1086 } 1087 1088 emergency_buffer = pv; 1089 emergency_buffer_size = Size; 1090 } 1091 do_croak: 1092 MALLOC_UNLOCK; 1093 emergency_sbrk_croak("Out of memory during request for %"UVuf" bytes, total sbrk() is %"UVuf" bytes", (UV)size, (UV)(goodsbrk + sbrk_slack)); 1094 /* NOTREACHED */ 1095 return NULL; 1096 } 1097 1098 #else /* !defined(PERL_EMERGENCY_SBRK) */ 1099 # define emergency_sbrk(size) -1 1100 #endif /* defined PERL_EMERGENCY_SBRK */ 1101 1102 static void 1103 write2(const char *mess) 1104 { 1105 write(2, mess, strlen(mess)); 1106 } 1107 1108 #ifdef DEBUGGING 1109 #undef ASSERT 1110 #define ASSERT(p,diag) if (!(p)) botch(diag,STRINGIFY(p),__FILE__,__LINE__); 1111 1112 static void 1113 botch(const char *diag, const char *s, const char *file, int line) 1114 { 1115 dVAR; 1116 dTHX; 1117 if (!(PERL_MAYBE_ALIVE && PERL_GET_THX)) 1118 goto do_write; 1119 else { 1120 if (PerlIO_printf(PerlIO_stderr(), 1121 "assertion botched (%s?): %s %s:%d\n", 1122 diag, s, file, line) != 0) { 1123 do_write: /* Can be initializing interpreter */ 1124 write2("assertion botched ("); 1125 write2(diag); 1126 write2("?): "); 1127 write2(s); 1128 write2(" ("); 1129 write2(file); 1130 write2(":"); 1131 { 1132 char linebuf[10]; 1133 char *s = linebuf + sizeof(linebuf) - 1; 1134 int n = line; 1135 *s = 0; 1136 do { 1137 *--s = '0' + (n % 10); 1138 } while (n /= 10); 1139 write2(s); 1140 } 1141 write2(")\n"); 1142 } 1143 PerlProc_abort(); 1144 } 1145 } 1146 #else 1147 #define ASSERT(p, diag) 1148 #endif 1149 1150 #ifdef MALLOC_FILL 1151 /* Fill should be long enough to cover long */ 1152 static void 1153 fill_pat_4bytes(unsigned char *s, size_t nbytes, const unsigned char *fill) 1154 { 1155 unsigned char *e = s + nbytes; 1156 long *lp; 1157 const long lfill = *(long*)fill; 1158 1159 if (PTR2UV(s) & (sizeof(long)-1)) { /* Align the pattern */ 1160 int shift = sizeof(long) - (PTR2UV(s) & (sizeof(long)-1)); 1161 unsigned const char *f = fill + sizeof(long) - shift; 1162 unsigned char *e1 = s + shift; 1163 1164 while (s < e1) 1165 *s++ = *f++; 1166 } 1167 lp = (long*)s; 1168 while ((unsigned char*)(lp + 1) <= e) 1169 *lp++ = lfill; 1170 s = (unsigned char*)lp; 1171 while (s < e) 1172 *s++ = *fill++; 1173 } 1174 /* Just malloc()ed */ 1175 static const unsigned char fill_feedadad[] = 1176 {0xFE, 0xED, 0xAD, 0xAD, 0xFE, 0xED, 0xAD, 0xAD, 1177 0xFE, 0xED, 0xAD, 0xAD, 0xFE, 0xED, 0xAD, 0xAD}; 1178 /* Just free()ed */ 1179 static const unsigned char fill_deadbeef[] = 1180 {0xDE, 0xAD, 0xBE, 0xEF, 0xDE, 0xAD, 0xBE, 0xEF, 1181 0xDE, 0xAD, 0xBE, 0xEF, 0xDE, 0xAD, 0xBE, 0xEF}; 1182 # define FILL_DEADBEEF(s, n) \ 1183 (void)(FILL_DEAD? (fill_pat_4bytes((s), (n), fill_deadbeef), 0) : 0) 1184 # define FILL_FEEDADAD(s, n) \ 1185 (void)(FILL_ALIVE? (fill_pat_4bytes((s), (n), fill_feedadad), 0) : 0) 1186 #else 1187 # define FILL_DEADBEEF(s, n) ((void)0) 1188 # define FILL_FEEDADAD(s, n) ((void)0) 1189 # undef MALLOC_FILL_CHECK 1190 #endif 1191 1192 #ifdef MALLOC_FILL_CHECK 1193 static int 1194 cmp_pat_4bytes(unsigned char *s, size_t nbytes, const unsigned char *fill) 1195 { 1196 unsigned char *e = s + nbytes; 1197 long *lp; 1198 const long lfill = *(long*)fill; 1199 1200 if (PTR2UV(s) & (sizeof(long)-1)) { /* Align the pattern */ 1201 int shift = sizeof(long) - (PTR2UV(s) & (sizeof(long)-1)); 1202 unsigned const char *f = fill + sizeof(long) - shift; 1203 unsigned char *e1 = s + shift; 1204 1205 while (s < e1) 1206 if (*s++ != *f++) 1207 return 1; 1208 } 1209 lp = (long*)s; 1210 while ((unsigned char*)(lp + 1) <= e) 1211 if (*lp++ != lfill) 1212 return 1; 1213 s = (unsigned char*)lp; 1214 while (s < e) 1215 if (*s++ != *fill++) 1216 return 1; 1217 return 0; 1218 } 1219 # define FILLCHECK_DEADBEEF(s, n) \ 1220 ASSERT(!FILL_CHECK || !cmp_pat_4bytes(s, n, fill_deadbeef), \ 1221 "free()ed/realloc()ed-away memory was overwritten") 1222 #else 1223 # define FILLCHECK_DEADBEEF(s, n) ((void)0) 1224 #endif 1225 1226 int 1227 S_ajust_size_and_find_bucket(size_t *nbytes_p) 1228 { 1229 MEM_SIZE shiftr; 1230 int bucket; 1231 size_t nbytes = *nbytes_p; 1232 1233 /* 1234 * Convert amount of memory requested into 1235 * closest block size stored in hash buckets 1236 * which satisfies request. Account for 1237 * space used per block for accounting. 1238 */ 1239 #ifdef PACK_MALLOC 1240 # ifdef SMALL_BUCKET_VIA_TABLE 1241 if (nbytes == 0) 1242 bucket = MIN_BUCKET; 1243 else if (nbytes <= SIZE_TABLE_MAX) { 1244 bucket = bucket_of[(nbytes - 1) >> BUCKET_TABLE_SHIFT]; 1245 } else 1246 # else 1247 if (nbytes == 0) 1248 nbytes = 1; 1249 if (nbytes <= MAX_POW2_ALGO) goto do_shifts; 1250 else 1251 # endif 1252 #endif 1253 { 1254 POW2_OPTIMIZE_ADJUST(nbytes); 1255 nbytes += M_OVERHEAD; 1256 nbytes = (nbytes + 3) &~ 3; 1257 #if defined(PACK_MALLOC) && !defined(SMALL_BUCKET_VIA_TABLE) 1258 do_shifts: 1259 #endif 1260 shiftr = (nbytes - 1) >> START_SHIFT; 1261 bucket = START_SHIFTS_BUCKET; 1262 /* apart from this loop, this is O(1) */ 1263 while (shiftr >>= 1) 1264 bucket += BUCKETS_PER_POW2; 1265 } 1266 *nbytes_p = nbytes; 1267 return bucket; 1268 } 1269 1270 Malloc_t 1271 Perl_malloc(size_t nbytes) 1272 { 1273 dVAR; 1274 register union overhead *p; 1275 register int bucket; 1276 1277 #if defined(DEBUGGING) || defined(RCHECK) 1278 MEM_SIZE size = nbytes; 1279 #endif 1280 1281 BARK_64K_LIMIT("Allocation",nbytes,nbytes); 1282 #ifdef DEBUGGING 1283 if ((long)nbytes < 0) 1284 croak("%s", "panic: malloc"); 1285 #endif 1286 1287 bucket = S_ajust_size_and_find_bucket(&nbytes); 1288 MALLOC_LOCK; 1289 /* 1290 * If nothing in hash bucket right now, 1291 * request more memory from the system. 1292 */ 1293 if (nextf[bucket] == NULL) 1294 morecore(bucket); 1295 if ((p = nextf[bucket]) == NULL) { 1296 MALLOC_UNLOCK; 1297 { 1298 dTHX; 1299 if (!PL_nomemok) { 1300 #if defined(PLAIN_MALLOC) && defined(NO_FANCY_MALLOC) 1301 PerlIO_puts(PerlIO_stderr(),"Out of memory!\n"); 1302 #else 1303 char buff[80]; 1304 char *eb = buff + sizeof(buff) - 1; 1305 char *s = eb; 1306 size_t n = nbytes; 1307 1308 PerlIO_puts(PerlIO_stderr(),"Out of memory during request for "); 1309 #if defined(DEBUGGING) || defined(RCHECK) 1310 n = size; 1311 #endif 1312 *s = 0; 1313 do { 1314 *--s = '0' + (n % 10); 1315 } while (n /= 10); 1316 PerlIO_puts(PerlIO_stderr(),s); 1317 PerlIO_puts(PerlIO_stderr()," bytes, total sbrk() is "); 1318 s = eb; 1319 n = goodsbrk + sbrk_slack; 1320 do { 1321 *--s = '0' + (n % 10); 1322 } while (n /= 10); 1323 PerlIO_puts(PerlIO_stderr(),s); 1324 PerlIO_puts(PerlIO_stderr()," bytes!\n"); 1325 #endif /* defined(PLAIN_MALLOC) && defined(NO_FANCY_MALLOC) */ 1326 my_exit(1); 1327 } 1328 } 1329 return (NULL); 1330 } 1331 1332 /* remove from linked list */ 1333 #ifdef DEBUGGING 1334 if ( (PTR2UV(p) & (MEM_ALIGNBYTES - 1)) 1335 /* Can't get this low */ 1336 || (p && PTR2UV(p) < (1<<LOG_OF_MIN_ARENA)) ) { 1337 dTHX; 1338 PerlIO_printf(PerlIO_stderr(), 1339 "Unaligned pointer in the free chain 0x%"UVxf"\n", 1340 PTR2UV(p)); 1341 } 1342 if ( (PTR2UV(p->ov_next) & (MEM_ALIGNBYTES - 1)) 1343 || (p->ov_next && PTR2UV(p->ov_next) < (1<<LOG_OF_MIN_ARENA)) ) { 1344 dTHX; 1345 PerlIO_printf(PerlIO_stderr(), 1346 "Unaligned \"next\" pointer in the free " 1347 "chain 0x%"UVxf" at 0x%"UVxf"\n", 1348 PTR2UV(p->ov_next), PTR2UV(p)); 1349 } 1350 #endif 1351 nextf[bucket] = p->ov_next; 1352 1353 MALLOC_UNLOCK; 1354 1355 DEBUG_m(PerlIO_printf(Perl_debug_log, 1356 "0x%"UVxf": (%05lu) malloc %ld bytes\n", 1357 PTR2UV((Malloc_t)(p + CHUNK_SHIFT)), (unsigned long)(PL_an++), 1358 (long)size)); 1359 1360 FILLCHECK_DEADBEEF((unsigned char*)(p + CHUNK_SHIFT), 1361 BUCKET_SIZE_REAL(bucket) + RMAGIC_SZ); 1362 1363 #ifdef IGNORE_SMALL_BAD_FREE 1364 if (bucket >= FIRST_BUCKET_WITH_CHECK) 1365 #endif 1366 OV_MAGIC(p, bucket) = MAGIC; 1367 #ifndef PACK_MALLOC 1368 OV_INDEX(p) = bucket; 1369 #endif 1370 #ifdef RCHECK 1371 /* 1372 * Record allocated size of block and 1373 * bound space with magic numbers. 1374 */ 1375 p->ov_rmagic = RMAGIC; 1376 if (bucket <= MAX_SHORT_BUCKET) { 1377 int i; 1378 1379 nbytes = size + M_OVERHEAD; 1380 p->ov_size = nbytes - 1; 1381 if ((i = nbytes & (RMAGIC_SZ-1))) { 1382 i = RMAGIC_SZ - i; 1383 while (i--) /* nbytes - RMAGIC_SZ is end of alloced area */ 1384 ((caddr_t)p + nbytes - RMAGIC_SZ)[i] = RMAGIC_C; 1385 } 1386 /* Same at RMAGIC_SZ-aligned RMAGIC */ 1387 nbytes = (nbytes + RMAGIC_SZ - 1) & ~(RMAGIC_SZ - 1); 1388 ((u_int *)((caddr_t)p + nbytes))[-1] = RMAGIC; 1389 } 1390 FILL_FEEDADAD((unsigned char *)(p + CHUNK_SHIFT), size); 1391 #endif 1392 return ((Malloc_t)(p + CHUNK_SHIFT)); 1393 } 1394 1395 static char *last_sbrk_top; 1396 static char *last_op; /* This arena can be easily extended. */ 1397 static MEM_SIZE sbrked_remains; 1398 1399 #ifdef DEBUGGING_MSTATS 1400 static int sbrks; 1401 #endif 1402 1403 struct chunk_chain_s { 1404 struct chunk_chain_s *next; 1405 MEM_SIZE size; 1406 }; 1407 static struct chunk_chain_s *chunk_chain; 1408 static int n_chunks; 1409 static char max_bucket; 1410 1411 /* Cutoff a piece of one of the chunks in the chain. Prefer smaller chunk. */ 1412 static void * 1413 get_from_chain(MEM_SIZE size) 1414 { 1415 struct chunk_chain_s *elt = chunk_chain, **oldp = &chunk_chain; 1416 struct chunk_chain_s **oldgoodp = NULL; 1417 long min_remain = LONG_MAX; 1418 1419 while (elt) { 1420 if (elt->size >= size) { 1421 long remains = elt->size - size; 1422 if (remains >= 0 && remains < min_remain) { 1423 oldgoodp = oldp; 1424 min_remain = remains; 1425 } 1426 if (remains == 0) { 1427 break; 1428 } 1429 } 1430 oldp = &( elt->next ); 1431 elt = elt->next; 1432 } 1433 if (!oldgoodp) return NULL; 1434 if (min_remain) { 1435 void *ret = *oldgoodp; 1436 struct chunk_chain_s *next = (*oldgoodp)->next; 1437 1438 *oldgoodp = (struct chunk_chain_s *)((char*)ret + size); 1439 (*oldgoodp)->size = min_remain; 1440 (*oldgoodp)->next = next; 1441 return ret; 1442 } else { 1443 void *ret = *oldgoodp; 1444 *oldgoodp = (*oldgoodp)->next; 1445 n_chunks--; 1446 return ret; 1447 } 1448 } 1449 1450 static void 1451 add_to_chain(void *p, MEM_SIZE size, MEM_SIZE chip) 1452 { 1453 struct chunk_chain_s *next = chunk_chain; 1454 char *cp = (char*)p; 1455 1456 cp += chip; 1457 chunk_chain = (struct chunk_chain_s *)cp; 1458 chunk_chain->size = size - chip; 1459 chunk_chain->next = next; 1460 n_chunks++; 1461 } 1462 1463 static void * 1464 get_from_bigger_buckets(int bucket, MEM_SIZE size) 1465 { 1466 int price = 1; 1467 static int bucketprice[NBUCKETS]; 1468 while (bucket <= max_bucket) { 1469 /* We postpone stealing from bigger buckets until we want it 1470 often enough. */ 1471 if (nextf[bucket] && bucketprice[bucket]++ >= price) { 1472 /* Steal it! */ 1473 void *ret = (void*)(nextf[bucket] - 1 + CHUNK_SHIFT); 1474 bucketprice[bucket] = 0; 1475 if (((char*)nextf[bucket]) - M_OVERHEAD == last_op) { 1476 last_op = NULL; /* Disable optimization */ 1477 } 1478 nextf[bucket] = nextf[bucket]->ov_next; 1479 #ifdef DEBUGGING_MSTATS 1480 nmalloc[bucket]--; 1481 start_slack -= M_OVERHEAD; 1482 #endif 1483 add_to_chain(ret, (BUCKET_SIZE_NO_SURPLUS(bucket) + 1484 POW2_OPTIMIZE_SURPLUS(bucket)), 1485 size); 1486 return ret; 1487 } 1488 bucket++; 1489 } 1490 return NULL; 1491 } 1492 1493 static union overhead * 1494 getpages(MEM_SIZE needed, int *nblksp, int bucket) 1495 { 1496 dVAR; 1497 /* Need to do (possibly expensive) system call. Try to 1498 optimize it for rare calling. */ 1499 MEM_SIZE require = needed - sbrked_remains; 1500 char *cp; 1501 union overhead *ovp; 1502 MEM_SIZE slack = 0; 1503 1504 if (sbrk_goodness > 0) { 1505 if (!last_sbrk_top && require < (MEM_SIZE)FIRST_SBRK) 1506 require = FIRST_SBRK; 1507 else if (require < (MEM_SIZE)MIN_SBRK) require = MIN_SBRK; 1508 1509 if (require < goodsbrk * MIN_SBRK_FRAC1000 / 1000) 1510 require = goodsbrk * MIN_SBRK_FRAC1000 / 1000; 1511 require = ((require - 1 + MIN_SBRK) / MIN_SBRK) * MIN_SBRK; 1512 } else { 1513 require = needed; 1514 last_sbrk_top = 0; 1515 sbrked_remains = 0; 1516 } 1517 1518 DEBUG_m(PerlIO_printf(Perl_debug_log, 1519 "sbrk(%ld) for %ld-byte-long arena\n", 1520 (long)require, (long) needed)); 1521 cp = (char *)sbrk(require); 1522 #ifdef DEBUGGING_MSTATS 1523 sbrks++; 1524 #endif 1525 if (cp == last_sbrk_top) { 1526 /* Common case, anything is fine. */ 1527 sbrk_goodness++; 1528 ovp = (union overhead *) (cp - sbrked_remains); 1529 last_op = cp - sbrked_remains; 1530 sbrked_remains = require - (needed - sbrked_remains); 1531 } else if (cp == (char *)-1) { /* no more room! */ 1532 ovp = (union overhead *)emergency_sbrk(needed); 1533 if (ovp == (union overhead *)-1) 1534 return 0; 1535 if (((char*)ovp) > last_op) { /* Cannot happen with current emergency_sbrk() */ 1536 last_op = 0; 1537 } 1538 return ovp; 1539 } else { /* Non-continuous or first sbrk(). */ 1540 long add = sbrked_remains; 1541 char *newcp; 1542 1543 if (sbrked_remains) { /* Put rest into chain, we 1544 cannot use it right now. */ 1545 add_to_chain((void*)(last_sbrk_top - sbrked_remains), 1546 sbrked_remains, 0); 1547 } 1548 1549 /* Second, check alignment. */ 1550 slack = 0; 1551 1552 #if !defined(atarist) /* on the atari we dont have to worry about this */ 1553 # ifndef I286 /* The sbrk(0) call on the I286 always returns the next segment */ 1554 /* WANTED_ALIGNMENT may be more than NEEDED_ALIGNMENT, but this may 1555 improve performance of memory access. */ 1556 if (PTR2UV(cp) & (WANTED_ALIGNMENT - 1)) { /* Not aligned. */ 1557 slack = WANTED_ALIGNMENT - (PTR2UV(cp) & (WANTED_ALIGNMENT - 1)); 1558 add += slack; 1559 } 1560 # endif 1561 #endif /* !atarist */ 1562 1563 if (add) { 1564 DEBUG_m(PerlIO_printf(Perl_debug_log, 1565 "sbrk(%ld) to fix non-continuous/off-page sbrk:\n\t%ld for alignement,\t%ld were assumed to come from the tail of the previous sbrk\n", 1566 (long)add, (long) slack, 1567 (long) sbrked_remains)); 1568 newcp = (char *)sbrk(add); 1569 #if defined(DEBUGGING_MSTATS) 1570 sbrks++; 1571 sbrk_slack += add; 1572 #endif 1573 if (newcp != cp + require) { 1574 /* Too bad: even rounding sbrk() is not continuous.*/ 1575 DEBUG_m(PerlIO_printf(Perl_debug_log, 1576 "failed to fix bad sbrk()\n")); 1577 #ifdef PACK_MALLOC 1578 if (slack) { 1579 MALLOC_UNLOCK; 1580 fatalcroak("panic: Off-page sbrk\n"); 1581 } 1582 #endif 1583 if (sbrked_remains) { 1584 /* Try again. */ 1585 #if defined(DEBUGGING_MSTATS) 1586 sbrk_slack += require; 1587 #endif 1588 require = needed; 1589 DEBUG_m(PerlIO_printf(Perl_debug_log, 1590 "straight sbrk(%ld)\n", 1591 (long)require)); 1592 cp = (char *)sbrk(require); 1593 #ifdef DEBUGGING_MSTATS 1594 sbrks++; 1595 #endif 1596 if (cp == (char *)-1) 1597 return 0; 1598 } 1599 sbrk_goodness = -1; /* Disable optimization! 1600 Continue with not-aligned... */ 1601 } else { 1602 cp += slack; 1603 require += sbrked_remains; 1604 } 1605 } 1606 1607 if (last_sbrk_top) { 1608 sbrk_goodness -= SBRK_FAILURE_PRICE; 1609 } 1610 1611 ovp = (union overhead *) cp; 1612 /* 1613 * Round up to minimum allocation size boundary 1614 * and deduct from block count to reflect. 1615 */ 1616 1617 # if NEEDED_ALIGNMENT > MEM_ALIGNBYTES 1618 if (PTR2UV(ovp) & (NEEDED_ALIGNMENT - 1)) 1619 fatalcroak("Misalignment of sbrk()\n"); 1620 else 1621 # endif 1622 #ifndef I286 /* Again, this should always be ok on an 80286 */ 1623 if (PTR2UV(ovp) & (MEM_ALIGNBYTES - 1)) { 1624 DEBUG_m(PerlIO_printf(Perl_debug_log, 1625 "fixing sbrk(): %d bytes off machine alignment\n", 1626 (int)(PTR2UV(ovp) & (MEM_ALIGNBYTES - 1)))); 1627 ovp = INT2PTR(union overhead *,(PTR2UV(ovp) + MEM_ALIGNBYTES) & 1628 (MEM_ALIGNBYTES - 1)); 1629 (*nblksp)--; 1630 # if defined(DEBUGGING_MSTATS) 1631 /* This is only approx. if TWO_POT_OPTIMIZE: */ 1632 sbrk_slack += (1 << (bucket >> BUCKET_POW2_SHIFT)); 1633 # endif 1634 } 1635 #endif 1636 ; /* Finish "else" */ 1637 sbrked_remains = require - needed; 1638 last_op = cp; 1639 } 1640 #if !defined(PLAIN_MALLOC) && !defined(NO_FANCY_MALLOC) 1641 emergency_buffer_last_req = 0; 1642 #endif 1643 last_sbrk_top = cp + require; 1644 #ifdef DEBUGGING_MSTATS 1645 goodsbrk += require; 1646 #endif 1647 return ovp; 1648 } 1649 1650 static int 1651 getpages_adjacent(MEM_SIZE require) 1652 { 1653 if (require <= sbrked_remains) { 1654 sbrked_remains -= require; 1655 } else { 1656 char *cp; 1657 1658 require -= sbrked_remains; 1659 /* We do not try to optimize sbrks here, we go for place. */ 1660 cp = (char*) sbrk(require); 1661 #ifdef DEBUGGING_MSTATS 1662 sbrks++; 1663 goodsbrk += require; 1664 #endif 1665 if (cp == last_sbrk_top) { 1666 sbrked_remains = 0; 1667 last_sbrk_top = cp + require; 1668 } else { 1669 if (cp == (char*)-1) { /* Out of memory */ 1670 #ifdef DEBUGGING_MSTATS 1671 goodsbrk -= require; 1672 #endif 1673 return 0; 1674 } 1675 /* Report the failure: */ 1676 if (sbrked_remains) 1677 add_to_chain((void*)(last_sbrk_top - sbrked_remains), 1678 sbrked_remains, 0); 1679 add_to_chain((void*)cp, require, 0); 1680 sbrk_goodness -= SBRK_FAILURE_PRICE; 1681 sbrked_remains = 0; 1682 last_sbrk_top = 0; 1683 last_op = 0; 1684 return 0; 1685 } 1686 } 1687 1688 return 1; 1689 } 1690 1691 /* 1692 * Allocate more memory to the indicated bucket. 1693 */ 1694 static void 1695 morecore(register int bucket) 1696 { 1697 dVAR; 1698 register union overhead *ovp; 1699 register int rnu; /* 2^rnu bytes will be requested */ 1700 int nblks; /* become nblks blocks of the desired size */ 1701 register MEM_SIZE siz, needed; 1702 static int were_called = 0; 1703 1704 if (nextf[bucket]) 1705 return; 1706 #ifndef NO_PERL_MALLOC_ENV 1707 if (!were_called) { 1708 /* It's the our first time. Initialize ourselves */ 1709 were_called = 1; /* Avoid a loop */ 1710 if (!MallocCfg[MallocCfg_skip_cfg_env]) { 1711 char *s = getenv("PERL_MALLOC_OPT"), *t = s, *off; 1712 const char *opts = PERL_MALLOC_OPT_CHARS; 1713 int changed = 0; 1714 1715 while ( t && t[0] && t[1] == '=' 1716 && ((off = strchr(opts, *t))) ) { 1717 IV val = 0; 1718 1719 t += 2; 1720 while (*t <= '9' && *t >= '0') 1721 val = 10*val + *t++ - '0'; 1722 if (!*t || *t == ';') { 1723 if (MallocCfg[off - opts] != val) 1724 changed = 1; 1725 MallocCfg[off - opts] = val; 1726 if (*t) 1727 t++; 1728 } 1729 } 1730 if (t && *t) { 1731 write2("Unrecognized part of PERL_MALLOC_OPT: \""); 1732 write2(t); 1733 write2("\"\n"); 1734 } 1735 if (changed) 1736 MallocCfg[MallocCfg_cfg_env_read] = 1; 1737 } 1738 } 1739 #endif 1740 if (bucket == sizeof(MEM_SIZE)*8*BUCKETS_PER_POW2) { 1741 MALLOC_UNLOCK; 1742 croak("%s", "Out of memory during ridiculously large request"); 1743 } 1744 if (bucket > max_bucket) 1745 max_bucket = bucket; 1746 1747 rnu = ( (bucket <= (LOG_OF_MIN_ARENA << BUCKET_POW2_SHIFT)) 1748 ? LOG_OF_MIN_ARENA 1749 : (bucket >> BUCKET_POW2_SHIFT) ); 1750 /* This may be overwritten later: */ 1751 nblks = 1 << (rnu - (bucket >> BUCKET_POW2_SHIFT)); /* how many blocks to get */ 1752 needed = ((MEM_SIZE)1 << rnu) + POW2_OPTIMIZE_SURPLUS(bucket); 1753 if (nextf[rnu << BUCKET_POW2_SHIFT]) { /* 2048b bucket. */ 1754 ovp = nextf[rnu << BUCKET_POW2_SHIFT] - 1 + CHUNK_SHIFT; 1755 nextf[rnu << BUCKET_POW2_SHIFT] 1756 = nextf[rnu << BUCKET_POW2_SHIFT]->ov_next; 1757 #ifdef DEBUGGING_MSTATS 1758 nmalloc[rnu << BUCKET_POW2_SHIFT]--; 1759 start_slack -= M_OVERHEAD; 1760 #endif 1761 DEBUG_m(PerlIO_printf(Perl_debug_log, 1762 "stealing %ld bytes from %ld arena\n", 1763 (long) needed, (long) rnu << BUCKET_POW2_SHIFT)); 1764 } else if (chunk_chain 1765 && (ovp = (union overhead*) get_from_chain(needed))) { 1766 DEBUG_m(PerlIO_printf(Perl_debug_log, 1767 "stealing %ld bytes from chain\n", 1768 (long) needed)); 1769 } else if ( (ovp = (union overhead*) 1770 get_from_bigger_buckets((rnu << BUCKET_POW2_SHIFT) + 1, 1771 needed)) ) { 1772 DEBUG_m(PerlIO_printf(Perl_debug_log, 1773 "stealing %ld bytes from bigger buckets\n", 1774 (long) needed)); 1775 } else if (needed <= sbrked_remains) { 1776 ovp = (union overhead *)(last_sbrk_top - sbrked_remains); 1777 sbrked_remains -= needed; 1778 last_op = (char*)ovp; 1779 } else 1780 ovp = getpages(needed, &nblks, bucket); 1781 1782 if (!ovp) 1783 return; 1784 FILL_DEADBEEF((unsigned char*)ovp, needed); 1785 1786 /* 1787 * Add new memory allocated to that on 1788 * free list for this hash bucket. 1789 */ 1790 siz = BUCKET_SIZE_NO_SURPLUS(bucket); /* No surplus if nblks > 1 */ 1791 #ifdef PACK_MALLOC 1792 *(u_char*)ovp = bucket; /* Fill index. */ 1793 if (bucket <= MAX_PACKED) { 1794 ovp = (union overhead *) ((char*)ovp + BLK_SHIFT(bucket)); 1795 nblks = N_BLKS(bucket); 1796 # ifdef DEBUGGING_MSTATS 1797 start_slack += BLK_SHIFT(bucket); 1798 # endif 1799 } else if (bucket < LOG_OF_MIN_ARENA * BUCKETS_PER_POW2) { 1800 ovp = (union overhead *) ((char*)ovp + BLK_SHIFT(bucket)); 1801 siz -= sizeof(union overhead); 1802 } else ovp++; /* One chunk per block. */ 1803 #endif /* PACK_MALLOC */ 1804 nextf[bucket] = ovp; 1805 #ifdef DEBUGGING_MSTATS 1806 nmalloc[bucket] += nblks; 1807 if (bucket > MAX_PACKED) { 1808 start_slack += M_OVERHEAD * nblks; 1809 } 1810 #endif 1811 1812 while (--nblks > 0) { 1813 ovp->ov_next = (union overhead *)((caddr_t)ovp + siz); 1814 ovp = (union overhead *)((caddr_t)ovp + siz); 1815 } 1816 /* Not all sbrks return zeroed memory.*/ 1817 ovp->ov_next = (union overhead *)NULL; 1818 #ifdef PACK_MALLOC 1819 if (bucket == 7*BUCKETS_PER_POW2) { /* Special case, explanation is above. */ 1820 union overhead *n_op = nextf[7*BUCKETS_PER_POW2]->ov_next; 1821 nextf[7*BUCKETS_PER_POW2] = 1822 (union overhead *)((caddr_t)nextf[7*BUCKETS_PER_POW2] 1823 - sizeof(union overhead)); 1824 nextf[7*BUCKETS_PER_POW2]->ov_next = n_op; 1825 } 1826 #endif /* !PACK_MALLOC */ 1827 } 1828 1829 Free_t 1830 Perl_mfree(Malloc_t where) 1831 { 1832 dVAR; 1833 register MEM_SIZE size; 1834 register union overhead *ovp; 1835 char *cp = (char*)where; 1836 #ifdef PACK_MALLOC 1837 u_char bucket; 1838 #endif 1839 1840 DEBUG_m(PerlIO_printf(Perl_debug_log, 1841 "0x%"UVxf": (%05lu) free\n", 1842 PTR2UV(cp), (unsigned long)(PL_an++))); 1843 1844 if (cp == NULL) 1845 return; 1846 #ifdef DEBUGGING 1847 if (PTR2UV(cp) & (MEM_ALIGNBYTES - 1)) 1848 croak("%s", "wrong alignment in free()"); 1849 #endif 1850 ovp = (union overhead *)((caddr_t)cp 1851 - sizeof (union overhead) * CHUNK_SHIFT); 1852 #ifdef PACK_MALLOC 1853 bucket = OV_INDEX(ovp); 1854 #endif 1855 #ifdef IGNORE_SMALL_BAD_FREE 1856 if ((bucket >= FIRST_BUCKET_WITH_CHECK) 1857 && (OV_MAGIC(ovp, bucket) != MAGIC)) 1858 #else 1859 if (OV_MAGIC(ovp, bucket) != MAGIC) 1860 #endif 1861 { 1862 static int bad_free_warn = -1; 1863 if (bad_free_warn == -1) { 1864 dTHX; 1865 char *pbf = PerlEnv_getenv("PERL_BADFREE"); 1866 bad_free_warn = (pbf) ? atoi(pbf) : 1; 1867 } 1868 if (!bad_free_warn) 1869 return; 1870 #ifdef RCHECK 1871 { 1872 dTHX; 1873 if (!PERL_IS_ALIVE || !PL_curcop) 1874 Perl_ck_warner_d(aTHX_ packWARN(WARN_MALLOC), "%s free() ignored (RMAGIC, PERL_CORE)", 1875 ovp->ov_rmagic == RMAGIC - 1 ? 1876 "Duplicate" : "Bad"); 1877 } 1878 #else 1879 { 1880 dTHX; 1881 if (!PERL_IS_ALIVE || !PL_curcop) 1882 Perl_ck_warner_d(aTHX_ packWARN(WARN_MALLOC), "%s", "Bad free() ignored (PERL_CORE)"); 1883 } 1884 #endif 1885 return; /* sanity */ 1886 } 1887 #ifdef RCHECK 1888 ASSERT(ovp->ov_rmagic == RMAGIC, "chunk's head overwrite"); 1889 if (OV_INDEX(ovp) <= MAX_SHORT_BUCKET) { 1890 int i; 1891 MEM_SIZE nbytes = ovp->ov_size + 1; 1892 1893 if ((i = nbytes & (RMAGIC_SZ-1))) { 1894 i = RMAGIC_SZ - i; 1895 while (i--) { /* nbytes - RMAGIC_SZ is end of alloced area */ 1896 ASSERT(((caddr_t)ovp + nbytes - RMAGIC_SZ)[i] == RMAGIC_C, 1897 "chunk's tail overwrite"); 1898 } 1899 } 1900 /* Same at RMAGIC_SZ-aligned RMAGIC */ 1901 nbytes = (nbytes + (RMAGIC_SZ-1)) & ~(RMAGIC_SZ-1); 1902 ASSERT(((u_int *)((caddr_t)ovp + nbytes))[-1] == RMAGIC, 1903 "chunk's tail overwrite"); 1904 FILLCHECK_DEADBEEF((unsigned char*)((caddr_t)ovp + nbytes), 1905 BUCKET_SIZE(OV_INDEX(ovp)) - nbytes); 1906 } 1907 FILL_DEADBEEF((unsigned char*)(ovp+CHUNK_SHIFT), 1908 BUCKET_SIZE_REAL(OV_INDEX(ovp)) + RMAGIC_SZ); 1909 ovp->ov_rmagic = RMAGIC - 1; 1910 #endif 1911 ASSERT(OV_INDEX(ovp) < NBUCKETS, "chunk's head overwrite"); 1912 size = OV_INDEX(ovp); 1913 1914 MALLOC_LOCK; 1915 ovp->ov_next = nextf[size]; 1916 nextf[size] = ovp; 1917 MALLOC_UNLOCK; 1918 } 1919 1920 /* There is no need to do any locking in realloc (with an exception of 1921 trying to grow in place if we are at the end of the chain). 1922 If somebody calls us from a different thread with the same address, 1923 we are sole anyway. */ 1924 1925 Malloc_t 1926 Perl_realloc(void *mp, size_t nbytes) 1927 { 1928 dVAR; 1929 register MEM_SIZE onb; 1930 union overhead *ovp; 1931 char *res; 1932 int prev_bucket; 1933 register int bucket; 1934 int incr; /* 1 if does not fit, -1 if "easily" fits in a 1935 smaller bucket, otherwise 0. */ 1936 char *cp = (char*)mp; 1937 1938 #ifdef DEBUGGING 1939 MEM_SIZE size = nbytes; 1940 1941 if ((long)nbytes < 0) 1942 croak("%s", "panic: realloc"); 1943 #endif 1944 1945 BARK_64K_LIMIT("Reallocation",nbytes,size); 1946 if (!cp) 1947 return Perl_malloc(nbytes); 1948 1949 ovp = (union overhead *)((caddr_t)cp 1950 - sizeof (union overhead) * CHUNK_SHIFT); 1951 bucket = OV_INDEX(ovp); 1952 1953 #ifdef IGNORE_SMALL_BAD_FREE 1954 if ((bucket >= FIRST_BUCKET_WITH_CHECK) 1955 && (OV_MAGIC(ovp, bucket) != MAGIC)) 1956 #else 1957 if (OV_MAGIC(ovp, bucket) != MAGIC) 1958 #endif 1959 { 1960 static int bad_free_warn = -1; 1961 if (bad_free_warn == -1) { 1962 dTHX; 1963 char *pbf = PerlEnv_getenv("PERL_BADFREE"); 1964 bad_free_warn = (pbf) ? atoi(pbf) : 1; 1965 } 1966 if (!bad_free_warn) 1967 return NULL; 1968 #ifdef RCHECK 1969 { 1970 dTHX; 1971 if (!PERL_IS_ALIVE || !PL_curcop) 1972 Perl_ck_warner_d(aTHX_ packWARN(WARN_MALLOC), "%srealloc() %signored", 1973 (ovp->ov_rmagic == RMAGIC - 1 ? "" : "Bad "), 1974 ovp->ov_rmagic == RMAGIC - 1 1975 ? "of freed memory " : ""); 1976 } 1977 #else 1978 { 1979 dTHX; 1980 if (!PERL_IS_ALIVE || !PL_curcop) 1981 Perl_ck_warner_d(aTHX_ packWARN(WARN_MALLOC), "%s", 1982 "Bad realloc() ignored"); 1983 } 1984 #endif 1985 return NULL; /* sanity */ 1986 } 1987 1988 onb = BUCKET_SIZE_REAL(bucket); 1989 /* 1990 * avoid the copy if same size block. 1991 * We are not aggressive with boundary cases. Note that it might 1992 * (for a small number of cases) give false negative if 1993 * both new size and old one are in the bucket for 1994 * FIRST_BIG_POW2, but the new one is near the lower end. 1995 * 1996 * We do not try to go to 1.5 times smaller bucket so far. 1997 */ 1998 if (nbytes > onb) incr = 1; 1999 else { 2000 #ifdef DO_NOT_TRY_HARDER_WHEN_SHRINKING 2001 if ( /* This is a little bit pessimal if PACK_MALLOC: */ 2002 nbytes > ( (onb >> 1) - M_OVERHEAD ) 2003 # ifdef TWO_POT_OPTIMIZE 2004 || (bucket == FIRST_BIG_POW2 && nbytes >= LAST_SMALL_BOUND ) 2005 # endif 2006 ) 2007 #else /* !DO_NOT_TRY_HARDER_WHEN_SHRINKING */ 2008 prev_bucket = ( (bucket > MAX_PACKED + 1) 2009 ? bucket - BUCKETS_PER_POW2 2010 : bucket - 1); 2011 if (nbytes > BUCKET_SIZE_REAL(prev_bucket)) 2012 #endif /* !DO_NOT_TRY_HARDER_WHEN_SHRINKING */ 2013 incr = 0; 2014 else incr = -1; 2015 } 2016 #ifdef STRESS_REALLOC 2017 goto hard_way; 2018 #endif 2019 if (incr == 0) { 2020 inplace_label: 2021 #ifdef RCHECK 2022 /* 2023 * Record new allocated size of block and 2024 * bound space with magic numbers. 2025 */ 2026 if (OV_INDEX(ovp) <= MAX_SHORT_BUCKET) { 2027 int i, nb = ovp->ov_size + 1; 2028 2029 if ((i = nb & (RMAGIC_SZ-1))) { 2030 i = RMAGIC_SZ - i; 2031 while (i--) { /* nb - RMAGIC_SZ is end of alloced area */ 2032 ASSERT(((caddr_t)ovp + nb - RMAGIC_SZ)[i] == RMAGIC_C, "chunk's tail overwrite"); 2033 } 2034 } 2035 /* Same at RMAGIC_SZ-aligned RMAGIC */ 2036 nb = (nb + (RMAGIC_SZ-1)) & ~(RMAGIC_SZ-1); 2037 ASSERT(((u_int *)((caddr_t)ovp + nb))[-1] == RMAGIC, 2038 "chunk's tail overwrite"); 2039 FILLCHECK_DEADBEEF((unsigned char*)((caddr_t)ovp + nb), 2040 BUCKET_SIZE(OV_INDEX(ovp)) - nb); 2041 if (nbytes > ovp->ov_size + 1 - M_OVERHEAD) 2042 FILL_FEEDADAD((unsigned char*)cp + ovp->ov_size + 1 - M_OVERHEAD, 2043 nbytes - (ovp->ov_size + 1 - M_OVERHEAD)); 2044 else 2045 FILL_DEADBEEF((unsigned char*)cp + nbytes, 2046 nb - M_OVERHEAD + RMAGIC_SZ - nbytes); 2047 /* 2048 * Convert amount of memory requested into 2049 * closest block size stored in hash buckets 2050 * which satisfies request. Account for 2051 * space used per block for accounting. 2052 */ 2053 nbytes += M_OVERHEAD; 2054 ovp->ov_size = nbytes - 1; 2055 if ((i = nbytes & (RMAGIC_SZ-1))) { 2056 i = RMAGIC_SZ - i; 2057 while (i--) /* nbytes - RMAGIC_SZ is end of alloced area */ 2058 ((caddr_t)ovp + nbytes - RMAGIC_SZ)[i] 2059 = RMAGIC_C; 2060 } 2061 /* Same at RMAGIC_SZ-aligned RMAGIC */ 2062 nbytes = (nbytes + (RMAGIC_SZ-1)) & ~(RMAGIC_SZ - 1); 2063 ((u_int *)((caddr_t)ovp + nbytes))[-1] = RMAGIC; 2064 } 2065 #endif 2066 res = cp; 2067 DEBUG_m(PerlIO_printf(Perl_debug_log, 2068 "0x%"UVxf": (%05lu) realloc %ld bytes inplace\n", 2069 PTR2UV(res),(unsigned long)(PL_an++), 2070 (long)size)); 2071 } else if (incr == 1 && (cp - M_OVERHEAD == last_op) 2072 && (onb > (1 << LOG_OF_MIN_ARENA))) { 2073 MEM_SIZE require, newarena = nbytes, pow; 2074 int shiftr; 2075 2076 POW2_OPTIMIZE_ADJUST(newarena); 2077 newarena = newarena + M_OVERHEAD; 2078 /* newarena = (newarena + 3) &~ 3; */ 2079 shiftr = (newarena - 1) >> LOG_OF_MIN_ARENA; 2080 pow = LOG_OF_MIN_ARENA + 1; 2081 /* apart from this loop, this is O(1) */ 2082 while (shiftr >>= 1) 2083 pow++; 2084 newarena = (1 << pow) + POW2_OPTIMIZE_SURPLUS(pow * BUCKETS_PER_POW2); 2085 require = newarena - onb - M_OVERHEAD; 2086 2087 MALLOC_LOCK; 2088 if (cp - M_OVERHEAD == last_op /* We *still* are the last chunk */ 2089 && getpages_adjacent(require)) { 2090 #ifdef DEBUGGING_MSTATS 2091 nmalloc[bucket]--; 2092 nmalloc[pow * BUCKETS_PER_POW2]++; 2093 #endif 2094 if (pow * BUCKETS_PER_POW2 > (MEM_SIZE)max_bucket) 2095 max_bucket = pow * BUCKETS_PER_POW2; 2096 *(cp - M_OVERHEAD) = pow * BUCKETS_PER_POW2; /* Fill index. */ 2097 MALLOC_UNLOCK; 2098 goto inplace_label; 2099 } else { 2100 MALLOC_UNLOCK; 2101 goto hard_way; 2102 } 2103 } else { 2104 hard_way: 2105 DEBUG_m(PerlIO_printf(Perl_debug_log, 2106 "0x%"UVxf": (%05lu) realloc %ld bytes the hard way\n", 2107 PTR2UV(cp),(unsigned long)(PL_an++), 2108 (long)size)); 2109 if ((res = (char*)Perl_malloc(nbytes)) == NULL) 2110 return (NULL); 2111 if (cp != res) /* common optimization */ 2112 Copy(cp, res, (MEM_SIZE)(nbytes<onb?nbytes:onb), char); 2113 Perl_mfree(cp); 2114 } 2115 return ((Malloc_t)res); 2116 } 2117 2118 Malloc_t 2119 Perl_calloc(register size_t elements, register size_t size) 2120 { 2121 long sz = elements * size; 2122 Malloc_t p = Perl_malloc(sz); 2123 2124 if (p) { 2125 memset((void*)p, 0, sz); 2126 } 2127 return p; 2128 } 2129 2130 char * 2131 Perl_strdup(const char *s) 2132 { 2133 MEM_SIZE l = strlen(s); 2134 char *s1 = (char *)Perl_malloc(l+1); 2135 2136 return (char *)CopyD(s, s1, (MEM_SIZE)(l+1), char); 2137 } 2138 2139 int 2140 Perl_putenv(char *a) 2141 { 2142 /* Sometimes system's putenv conflicts with my_setenv() - this is system 2143 malloc vs Perl's free(). */ 2144 dTHX; 2145 char *var; 2146 char *val = a; 2147 MEM_SIZE l; 2148 char buf[80]; 2149 2150 while (*val && *val != '=') 2151 val++; 2152 if (!*val) 2153 return -1; 2154 l = val - a; 2155 if (l < sizeof(buf)) 2156 var = buf; 2157 else 2158 var = (char *)Perl_malloc(l + 1); 2159 Copy(a, var, l, char); 2160 var[l + 1] = 0; 2161 my_setenv(var, val+1); 2162 if (var != buf) 2163 Perl_mfree(var); 2164 return 0; 2165 } 2166 2167 MEM_SIZE 2168 Perl_malloced_size(void *p) 2169 { 2170 union overhead * const ovp = (union overhead *) 2171 ((caddr_t)p - sizeof (union overhead) * CHUNK_SHIFT); 2172 const int bucket = OV_INDEX(ovp); 2173 2174 PERL_ARGS_ASSERT_MALLOCED_SIZE; 2175 2176 #ifdef RCHECK 2177 /* The caller wants to have a complete control over the chunk, 2178 disable the memory checking inside the chunk. */ 2179 if (bucket <= MAX_SHORT_BUCKET) { 2180 const MEM_SIZE size = BUCKET_SIZE_REAL(bucket); 2181 ovp->ov_size = size + M_OVERHEAD - 1; 2182 *((u_int *)((caddr_t)ovp + size + M_OVERHEAD - RMAGIC_SZ)) = RMAGIC; 2183 } 2184 #endif 2185 return BUCKET_SIZE_REAL(bucket); 2186 } 2187 2188 2189 MEM_SIZE 2190 Perl_malloc_good_size(size_t wanted) 2191 { 2192 return BUCKET_SIZE_REAL(S_ajust_size_and_find_bucket(&wanted)); 2193 } 2194 2195 # ifdef BUCKETS_ROOT2 2196 # define MIN_EVEN_REPORT 6 2197 # else 2198 # define MIN_EVEN_REPORT MIN_BUCKET 2199 # endif 2200 2201 int 2202 Perl_get_mstats(pTHX_ perl_mstats_t *buf, int buflen, int level) 2203 { 2204 #ifdef DEBUGGING_MSTATS 2205 register int i, j; 2206 register union overhead *p; 2207 struct chunk_chain_s* nextchain; 2208 2209 PERL_ARGS_ASSERT_GET_MSTATS; 2210 2211 buf->topbucket = buf->topbucket_ev = buf->topbucket_odd 2212 = buf->totfree = buf->total = buf->total_chain = 0; 2213 2214 buf->minbucket = MIN_BUCKET; 2215 MALLOC_LOCK; 2216 for (i = MIN_BUCKET ; i < NBUCKETS; i++) { 2217 for (j = 0, p = nextf[i]; p; p = p->ov_next, j++) 2218 ; 2219 if (i < buflen) { 2220 buf->nfree[i] = j; 2221 buf->ntotal[i] = nmalloc[i]; 2222 } 2223 buf->totfree += j * BUCKET_SIZE_REAL(i); 2224 buf->total += nmalloc[i] * BUCKET_SIZE_REAL(i); 2225 if (nmalloc[i]) { 2226 i % 2 ? (buf->topbucket_odd = i) : (buf->topbucket_ev = i); 2227 buf->topbucket = i; 2228 } 2229 } 2230 nextchain = chunk_chain; 2231 while (nextchain) { 2232 buf->total_chain += nextchain->size; 2233 nextchain = nextchain->next; 2234 } 2235 buf->total_sbrk = goodsbrk + sbrk_slack; 2236 buf->sbrks = sbrks; 2237 buf->sbrk_good = sbrk_goodness; 2238 buf->sbrk_slack = sbrk_slack; 2239 buf->start_slack = start_slack; 2240 buf->sbrked_remains = sbrked_remains; 2241 MALLOC_UNLOCK; 2242 buf->nbuckets = NBUCKETS; 2243 if (level) { 2244 for (i = MIN_BUCKET ; i < NBUCKETS; i++) { 2245 if (i >= buflen) 2246 break; 2247 buf->bucket_mem_size[i] = BUCKET_SIZE_NO_SURPLUS(i); 2248 buf->bucket_available_size[i] = BUCKET_SIZE_REAL(i); 2249 } 2250 } 2251 #else /* defined DEBUGGING_MSTATS */ 2252 PerlIO_printf(Perl_error_log, "perl not compiled with DEBUGGING_MSTATS\n"); 2253 #endif /* defined DEBUGGING_MSTATS */ 2254 return 0; /* XXX unused */ 2255 } 2256 /* 2257 * mstats - print out statistics about malloc 2258 * 2259 * Prints two lines of numbers, one showing the length of the free list 2260 * for each size category, the second showing the number of mallocs - 2261 * frees for each size category. 2262 */ 2263 void 2264 Perl_dump_mstats(pTHX_ const char *s) 2265 { 2266 #ifdef DEBUGGING_MSTATS 2267 register int i; 2268 perl_mstats_t buffer; 2269 UV nf[NBUCKETS]; 2270 UV nt[NBUCKETS]; 2271 2272 PERL_ARGS_ASSERT_DUMP_MSTATS; 2273 2274 buffer.nfree = nf; 2275 buffer.ntotal = nt; 2276 get_mstats(&buffer, NBUCKETS, 0); 2277 2278 if (s) 2279 PerlIO_printf(Perl_error_log, 2280 "Memory allocation statistics %s (buckets %"IVdf"(%"IVdf")..%"IVdf"(%"IVdf")\n", 2281 s, 2282 (IV)BUCKET_SIZE_REAL(MIN_BUCKET), 2283 (IV)BUCKET_SIZE_NO_SURPLUS(MIN_BUCKET), 2284 (IV)BUCKET_SIZE_REAL(buffer.topbucket), 2285 (IV)BUCKET_SIZE_NO_SURPLUS(buffer.topbucket)); 2286 PerlIO_printf(Perl_error_log, "%8"IVdf" free:", buffer.totfree); 2287 for (i = MIN_EVEN_REPORT; i <= buffer.topbucket; i += BUCKETS_PER_POW2) { 2288 PerlIO_printf(Perl_error_log, 2289 ((i < 8*BUCKETS_PER_POW2 || i == 10*BUCKETS_PER_POW2) 2290 ? " %5"UVuf 2291 : ((i < 12*BUCKETS_PER_POW2) ? " %3"UVuf : " %"UVuf)), 2292 buffer.nfree[i]); 2293 } 2294 #ifdef BUCKETS_ROOT2 2295 PerlIO_printf(Perl_error_log, "\n\t "); 2296 for (i = MIN_BUCKET + 1; i <= buffer.topbucket_odd; i += BUCKETS_PER_POW2) { 2297 PerlIO_printf(Perl_error_log, 2298 ((i < 8*BUCKETS_PER_POW2 || i == 10*BUCKETS_PER_POW2) 2299 ? " %5"UVuf 2300 : ((i < 12*BUCKETS_PER_POW2) ? " %3"UVuf : " %"UVuf)), 2301 buffer.nfree[i]); 2302 } 2303 #endif 2304 PerlIO_printf(Perl_error_log, "\n%8"IVdf" used:", buffer.total - buffer.totfree); 2305 for (i = MIN_EVEN_REPORT; i <= buffer.topbucket; i += BUCKETS_PER_POW2) { 2306 PerlIO_printf(Perl_error_log, 2307 ((i < 8*BUCKETS_PER_POW2 || i == 10*BUCKETS_PER_POW2) 2308 ? " %5"IVdf 2309 : ((i < 12*BUCKETS_PER_POW2) ? " %3"IVdf : " %"IVdf)), 2310 buffer.ntotal[i] - buffer.nfree[i]); 2311 } 2312 #ifdef BUCKETS_ROOT2 2313 PerlIO_printf(Perl_error_log, "\n\t "); 2314 for (i = MIN_BUCKET + 1; i <= buffer.topbucket_odd; i += BUCKETS_PER_POW2) { 2315 PerlIO_printf(Perl_error_log, 2316 ((i < 8*BUCKETS_PER_POW2 || i == 10*BUCKETS_PER_POW2) 2317 ? " %5"IVdf 2318 : ((i < 12*BUCKETS_PER_POW2) ? " %3"IVdf : " %"IVdf)), 2319 buffer.ntotal[i] - buffer.nfree[i]); 2320 } 2321 #endif 2322 PerlIO_printf(Perl_error_log, "\nTotal sbrk(): %"IVdf"/%"IVdf":%"IVdf". Odd ends: pad+heads+chain+tail: %"IVdf"+%"IVdf"+%"IVdf"+%"IVdf".\n", 2323 buffer.total_sbrk, buffer.sbrks, buffer.sbrk_good, 2324 buffer.sbrk_slack, buffer.start_slack, 2325 buffer.total_chain, buffer.sbrked_remains); 2326 #else /* DEBUGGING_MSTATS */ 2327 PerlIO_printf(Perl_error_log, "%s: perl not compiled with DEBUGGING_MSTATS\n",s); 2328 #endif /* DEBUGGING_MSTATS */ 2329 } 2330 2331 #ifdef USE_PERL_SBRK 2332 2333 # if defined(NeXT) || defined(__NeXT__) || defined(PURIFY) 2334 # define PERL_SBRK_VIA_MALLOC 2335 # endif 2336 2337 # ifdef PERL_SBRK_VIA_MALLOC 2338 2339 /* it may seem schizophrenic to use perl's malloc and let it call system */ 2340 /* malloc, the reason for that is only the 3.2 version of the OS that had */ 2341 /* frequent core dumps within nxzonefreenolock. This sbrk routine put an */ 2342 /* end to the cores */ 2343 2344 # ifndef SYSTEM_ALLOC 2345 # define SYSTEM_ALLOC(a) malloc(a) 2346 # endif 2347 # ifndef SYSTEM_ALLOC_ALIGNMENT 2348 # define SYSTEM_ALLOC_ALIGNMENT MEM_ALIGNBYTES 2349 # endif 2350 2351 # endif /* PERL_SBRK_VIA_MALLOC */ 2352 2353 static IV Perl_sbrk_oldchunk; 2354 static long Perl_sbrk_oldsize; 2355 2356 # define PERLSBRK_32_K (1<<15) 2357 # define PERLSBRK_64_K (1<<16) 2358 2359 Malloc_t 2360 Perl_sbrk(int size) 2361 { 2362 IV got; 2363 int small, reqsize; 2364 2365 if (!size) return 0; 2366 reqsize = size; /* just for the DEBUG_m statement */ 2367 #ifdef PACK_MALLOC 2368 size = (size + 0x7ff) & ~0x7ff; 2369 #endif 2370 if (size <= Perl_sbrk_oldsize) { 2371 got = Perl_sbrk_oldchunk; 2372 Perl_sbrk_oldchunk += size; 2373 Perl_sbrk_oldsize -= size; 2374 } else { 2375 if (size >= PERLSBRK_32_K) { 2376 small = 0; 2377 } else { 2378 size = PERLSBRK_64_K; 2379 small = 1; 2380 } 2381 # if NEEDED_ALIGNMENT > SYSTEM_ALLOC_ALIGNMENT 2382 size += NEEDED_ALIGNMENT - SYSTEM_ALLOC_ALIGNMENT; 2383 # endif 2384 got = (IV)SYSTEM_ALLOC(size); 2385 # if NEEDED_ALIGNMENT > SYSTEM_ALLOC_ALIGNMENT 2386 got = (got + NEEDED_ALIGNMENT - 1) & ~(NEEDED_ALIGNMENT - 1); 2387 # endif 2388 if (small) { 2389 /* Chunk is small, register the rest for future allocs. */ 2390 Perl_sbrk_oldchunk = got + reqsize; 2391 Perl_sbrk_oldsize = size - reqsize; 2392 } 2393 } 2394 2395 DEBUG_m(PerlIO_printf(Perl_debug_log, "sbrk malloc size %ld (reqsize %ld), left size %ld, give addr 0x%"UVxf"\n", 2396 size, reqsize, Perl_sbrk_oldsize, PTR2UV(got))); 2397 2398 return (void *)got; 2399 } 2400 2401 #endif /* ! defined USE_PERL_SBRK */ 2402 2403 /* 2404 * Local variables: 2405 * c-indentation-style: bsd 2406 * c-basic-offset: 4 2407 * indent-tabs-mode: t 2408 * End: 2409 * 2410 * ex: set ts=8 sts=4 sw=4 noet: 2411 */ 2412