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 #define LOG_OF_MIN_ARENA 11 201 202 #if defined(DEBUGGING) && !defined(NO_RCHECK) 203 # define RCHECK 204 #endif 205 #if defined(DEBUGGING) && !defined(NO_RCHECK) && !defined(NO_MFILL) && !defined(MALLOC_FILL) 206 # define MALLOC_FILL 207 #endif 208 #if defined(DEBUGGING) && !defined(NO_RCHECK) && !defined(NO_FILL_CHECK) && !defined(MALLOC_FILL_CHECK) 209 # define MALLOC_FILL_CHECK 210 #endif 211 #if defined(RCHECK) && defined(IGNORE_SMALL_BAD_FREE) 212 # undef IGNORE_SMALL_BAD_FREE 213 #endif 214 /* 215 * malloc.c (Caltech) 2/21/82 216 * Chris Kingsley, kingsley@cit-20. 217 * 218 * This is a very fast storage allocator. It allocates blocks of a small 219 * number of different sizes, and keeps free lists of each size. Blocks that 220 * don't exactly fit are passed up to the next larger size. In this 221 * implementation, the available sizes are 2^n-4 (or 2^n-12) bytes long. 222 * If PACK_MALLOC is defined, small blocks are 2^n bytes long. 223 * This is designed for use in a program that uses vast quantities of memory, 224 * but bombs when it runs out. 225 * 226 * Modifications Copyright Ilya Zakharevich 1996-99. 227 * 228 * Still very quick, but much more thrifty. (Std config is 10% slower 229 * than it was, and takes 67% of old heap size for typical usage.) 230 * 231 * Allocations of small blocks are now table-driven to many different 232 * buckets. Sizes of really big buckets are increased to accommodate 233 * common size=power-of-2 blocks. Running-out-of-memory is made into 234 * an exception. Deeply configurable and thread-safe. 235 * 236 */ 237 238 #include "EXTERN.h" 239 #define PERL_IN_MALLOC_C 240 #include "perl.h" 241 #if defined(MULTIPLICITY) 242 # define croak Perl_croak_nocontext 243 # define croak2 Perl_croak_nocontext 244 # define warn Perl_warn_nocontext 245 # define warn2 Perl_warn_nocontext 246 #else 247 # define croak2 croak 248 # define warn2 warn 249 #endif 250 #ifdef USE_ITHREADS 251 # define PERL_MAYBE_ALIVE PL_thr_key 252 #else 253 # define PERL_MAYBE_ALIVE 1 254 #endif 255 256 #ifndef MYMALLOC 257 # error "MYMALLOC is not defined" 258 #endif 259 260 #ifndef MUTEX_LOCK 261 # define MUTEX_LOCK(l) 262 #endif 263 264 #ifndef MUTEX_UNLOCK 265 # define MUTEX_UNLOCK(l) 266 #endif 267 268 #ifndef MALLOC_LOCK 269 # define MALLOC_LOCK MUTEX_LOCK(&PL_malloc_mutex) 270 #endif 271 272 #ifndef MALLOC_UNLOCK 273 # define MALLOC_UNLOCK MUTEX_UNLOCK(&PL_malloc_mutex) 274 #endif 275 276 # ifndef fatalcroak /* make depend */ 277 # define fatalcroak(mess) (write(2, (mess), strlen(mess)), exit(2)) 278 # endif 279 280 #ifdef DEBUGGING 281 # undef DEBUG_m 282 # define DEBUG_m(a) \ 283 STMT_START { \ 284 if (PERL_MAYBE_ALIVE && PERL_GET_THX) { \ 285 dTHX; \ 286 if (DEBUG_m_TEST) { \ 287 PL_debug &= ~DEBUG_m_FLAG; \ 288 a; \ 289 PL_debug |= DEBUG_m_FLAG; \ 290 } \ 291 } \ 292 } STMT_END 293 #endif 294 295 #ifdef MULTIPLICITY 296 # define PERL_IS_ALIVE aTHX 297 #else 298 # define PERL_IS_ALIVE TRUE 299 #endif 300 301 302 /* 303 * Layout of memory: 304 * ~~~~~~~~~~~~~~~~ 305 * The memory is broken into "blocks" which occupy multiples of 2K (and 306 * generally speaking, have size "close" to a power of 2). The addresses 307 * of such *unused* blocks are kept in nextf[i] with big enough i. (nextf 308 * is an array of linked lists.) (Addresses of used blocks are not known.) 309 * 310 * Moreover, since the algorithm may try to "bite" smaller blocks out 311 * of unused bigger ones, there are also regions of "irregular" size, 312 * managed separately, by a linked list chunk_chain. 313 * 314 * The third type of storage is the sbrk()ed-but-not-yet-used space, its 315 * end and size are kept in last_sbrk_top and sbrked_remains. 316 * 317 * Growing blocks "in place": 318 * ~~~~~~~~~~~~~~~~~~~~~~~~~ 319 * The address of the block with the greatest address is kept in last_op 320 * (if not known, last_op is 0). If it is known that the memory above 321 * last_op is not continuous, or contains a chunk from chunk_chain, 322 * last_op is set to 0. 323 * 324 * The chunk with address last_op may be grown by expanding into 325 * sbrk()ed-but-not-yet-used space, or trying to sbrk() more continuous 326 * memory. 327 * 328 * Management of last_op: 329 * ~~~~~~~~~~~~~~~~~~~~~ 330 * 331 * free() never changes the boundaries of blocks, so is not relevant. 332 * 333 * The only way realloc() may change the boundaries of blocks is if it 334 * grows a block "in place". However, in the case of success such a 335 * chunk is automatically last_op, and it remains last_op. In the case 336 * of failure getpages_adjacent() clears last_op. 337 * 338 * malloc() may change blocks by calling morecore() only. 339 * 340 * morecore() may create new blocks by: 341 * a) biting pieces from chunk_chain (cannot create one above last_op); 342 * b) biting a piece from an unused block (if block was last_op, this 343 * may create a chunk from chain above last_op, thus last_op is 344 * invalidated in such a case). 345 * c) biting of sbrk()ed-but-not-yet-used space. This creates 346 * a block which is last_op. 347 * d) Allocating new pages by calling getpages(); 348 * 349 * getpages() creates a new block. It marks last_op at the bottom of 350 * the chunk of memory it returns. 351 * 352 * Active pages footprint: 353 * ~~~~~~~~~~~~~~~~~~~~~~ 354 * Note that we do not need to traverse the lists in nextf[i], just take 355 * the first element of this list. However, we *need* to traverse the 356 * list in chunk_chain, but most the time it should be a very short one, 357 * so we do not step on a lot of pages we are not going to use. 358 * 359 * Flaws: 360 * ~~~~~ 361 * get_from_bigger_buckets(): forget to increment price => Quite 362 * aggressive. 363 */ 364 365 /* I don't much care whether these are defined in sys/types.h--LAW */ 366 367 #define u_char unsigned char 368 #define u_int unsigned int 369 /* 370 * I removed the definition of u_bigint which appeared to be u_bigint = UV 371 * u_bigint was only used in TWOK_MASKED and TWOK_SHIFT 372 * where I have used PTR2UV. RMB 373 */ 374 #define u_short unsigned short 375 376 #if defined(RCHECK) && defined(PACK_MALLOC) 377 # undef PACK_MALLOC 378 #endif 379 380 /* 381 * The description below is applicable if PACK_MALLOC is not defined. 382 * 383 * The overhead on a block is at least 4 bytes. When free, this space 384 * contains a pointer to the next free block, and the bottom two bits must 385 * be zero. When in use, the first byte is set to MAGIC, and the second 386 * byte is the size index. The remaining bytes are for alignment. 387 * If range checking is enabled and the size of the block fits 388 * in two bytes, then the top two bytes hold the size of the requested block 389 * plus the range checking words, and the header word MINUS ONE. 390 */ 391 union overhead { 392 union overhead *ov_next; /* when free */ 393 #if MEM_ALIGNBYTES > 4 394 double strut; /* alignment problems */ 395 # if MEM_ALIGNBYTES > 8 396 char sstrut[MEM_ALIGNBYTES]; /* for the sizing */ 397 # endif 398 #endif 399 struct { 400 /* 401 * Keep the ovu_index and ovu_magic in this order, having a char 402 * field first gives alignment indigestion in some systems, such as 403 * MachTen. 404 */ 405 u_char ovu_index; /* bucket # */ 406 u_char ovu_magic; /* magic number */ 407 #ifdef RCHECK 408 /* Subtract one to fit into u_short for an extra bucket */ 409 u_short ovu_size; /* block size (requested + overhead - 1) */ 410 u_int ovu_rmagic; /* range magic number */ 411 #endif 412 } ovu; 413 #define ov_magic ovu.ovu_magic 414 #define ov_index ovu.ovu_index 415 #define ov_size ovu.ovu_size 416 #define ov_rmagic ovu.ovu_rmagic 417 }; 418 419 #define MAGIC 0xff /* magic # on accounting info */ 420 #define RMAGIC 0x55555555 /* magic # on range info */ 421 #define RMAGIC_C 0x55 /* magic # on range info */ 422 423 #ifdef RCHECK 424 # define RMAGIC_SZ sizeof (u_int) /* Overhead at end of bucket */ 425 # ifdef TWO_POT_OPTIMIZE 426 # define MAX_SHORT_BUCKET (12 * BUCKETS_PER_POW2) /* size-1 fits in short */ 427 # else 428 # define MAX_SHORT_BUCKET (13 * BUCKETS_PER_POW2) 429 # endif 430 #else 431 # define RMAGIC_SZ 0 432 #endif 433 434 #if !defined(PACK_MALLOC) && defined(BUCKETS_ROOT2) 435 # undef BUCKETS_ROOT2 436 #endif 437 438 #ifdef BUCKETS_ROOT2 439 # define BUCKET_TABLE_SHIFT 2 440 # define BUCKET_POW2_SHIFT 1 441 # define BUCKETS_PER_POW2 2 442 #else 443 # define BUCKET_TABLE_SHIFT MIN_BUC_POW2 444 # define BUCKET_POW2_SHIFT 0 445 # define BUCKETS_PER_POW2 1 446 #endif 447 448 #if !defined(MEM_ALIGNBYTES) || ((MEM_ALIGNBYTES > 4) && !defined(STRICT_ALIGNMENT)) 449 /* Figure out the alignment of void*. */ 450 struct aligner { 451 char c; 452 void *p; 453 }; 454 # define ALIGN_SMALL ((IV)((caddr_t)&(((struct aligner*)0)->p))) 455 #else 456 # define ALIGN_SMALL MEM_ALIGNBYTES 457 #endif 458 459 #define IF_ALIGN_8(yes,no) ((ALIGN_SMALL>4) ? (yes) : (no)) 460 461 #ifdef BUCKETS_ROOT2 462 # define MAX_BUCKET_BY_TABLE 13 463 static const u_short buck_size[MAX_BUCKET_BY_TABLE + 1] = 464 { 465 0, 0, 0, 0, 4, 4, 8, 12, 16, 24, 32, 48, 64, 80, 466 }; 467 # define BUCKET_SIZE_NO_SURPLUS(i) ((i) % 2 ? buck_size[i] : (1 << ((i) >> BUCKET_POW2_SHIFT))) 468 # define BUCKET_SIZE_REAL(i) ((i) <= MAX_BUCKET_BY_TABLE \ 469 ? ((size_t)buck_size[i]) \ 470 : ((((size_t)1) << ((i) >> BUCKET_POW2_SHIFT)) \ 471 - MEM_OVERHEAD(i) \ 472 + POW2_OPTIMIZE_SURPLUS(i))) 473 #else 474 # define BUCKET_SIZE_NO_SURPLUS(i) (((size_t)1) << ((i) >> BUCKET_POW2_SHIFT)) 475 # define BUCKET_SIZE(i) (BUCKET_SIZE_NO_SURPLUS(i) + POW2_OPTIMIZE_SURPLUS(i)) 476 # define BUCKET_SIZE_REAL(i) (BUCKET_SIZE(i) - MEM_OVERHEAD(i)) 477 #endif 478 479 480 #ifdef PACK_MALLOC 481 /* In this case there are several possible layout of arenas depending 482 * on the size. Arenas are of sizes multiple to 2K, 2K-aligned, and 483 * have a size close to a power of 2. 484 * 485 * Arenas of the size >= 4K keep one chunk only. Arenas of size 2K 486 * may keep one chunk or multiple chunks. Here are the possible 487 * layouts of arenas: 488 * 489 * # One chunk only, chunksize 2^k + SOMETHING - ALIGN, k >= 11 490 * 491 * INDEX MAGIC1 UNUSED CHUNK1 492 * 493 * # Multichunk with sanity checking and chunksize 2^k-ALIGN, k>7 494 * 495 * INDEX MAGIC1 MAGIC2 MAGIC3 UNUSED CHUNK1 CHUNK2 CHUNK3 ... 496 * 497 * # Multichunk with sanity checking and size 2^k-ALIGN, k=7 498 * 499 * INDEX MAGIC1 MAGIC2 MAGIC3 UNUSED CHUNK1 UNUSED CHUNK2 CHUNK3 ... 500 * 501 * # Multichunk with sanity checking and size up to 80 502 * 503 * INDEX UNUSED MAGIC1 UNUSED MAGIC2 UNUSED ... CHUNK1 CHUNK2 CHUNK3 ... 504 * 505 * # No sanity check (usually up to 48=byte-long buckets) 506 * INDEX UNUSED CHUNK1 CHUNK2 ... 507 * 508 * Above INDEX and MAGIC are one-byte-long. Sizes of UNUSED are 509 * appropriate to keep algorithms simple and memory aligned. INDEX 510 * encodes the size of the chunk, while MAGICn encodes state (used, 511 * free or non-managed-by-us-so-it-indicates-a-bug) of CHUNKn. MAGIC 512 * is used for sanity checking purposes only. SOMETHING is 0 or 4K 513 * (to make size of big CHUNK accommodate allocations for powers of two 514 * better). 515 * 516 * [There is no need to alignment between chunks, since C rules ensure 517 * that structs which need 2^k alignment have sizeof which is 518 * divisible by 2^k. Thus as far as the last chunk is aligned at the 519 * end of the arena, and 2K-alignment does not contradict things, 520 * everything is going to be OK for sizes of chunks 2^n and 2^n + 521 * 2^k. Say, 80-bit buckets will be 16-bit aligned, and as far as we 522 * put allocations for requests in 65..80 range, all is fine. 523 * 524 * Note, however, that standard malloc() puts more strict 525 * requirements than the above C rules. Moreover, our algorithms of 526 * realloc() may break this idyll, but we suppose that realloc() does 527 * need not change alignment.] 528 * 529 * Is very important to make calculation of the offset of MAGICm as 530 * quick as possible, since it is done on each malloc()/free(). In 531 * fact it is so quick that it has quite little effect on the speed of 532 * doing malloc()/free(). [By default] We forego such calculations 533 * for small chunks, but only to save extra 3% of memory, not because 534 * of speed considerations. 535 * 536 * Here is the algorithm [which is the same for all the allocations 537 * schemes above], see OV_MAGIC(block,bucket). Let OFFSETm be the 538 * offset of the CHUNKm from the start of ARENA. Then offset of 539 * MAGICm is (OFFSET1 >> SHIFT) + ADDOFFSET. Here SHIFT and ADDOFFSET 540 * are numbers which depend on the size of the chunks only. 541 * 542 * Let as check some sanity conditions. Numbers OFFSETm>>SHIFT are 543 * different for all the chunks in the arena if 2^SHIFT is not greater 544 * than size of the chunks in the arena. MAGIC1 will not overwrite 545 * INDEX provided ADDOFFSET is >0 if OFFSET1 < 2^SHIFT. MAGIClast 546 * will not overwrite CHUNK1 if OFFSET1 > (OFFSETlast >> SHIFT) + 547 * ADDOFFSET. 548 * 549 * Make SHIFT the maximal possible (there is no point in making it 550 * smaller). Since OFFSETlast is 2K - CHUNKSIZE, above restrictions 551 * give restrictions on OFFSET1 and on ADDOFFSET. 552 * 553 * In particular, for chunks of size 2^k with k>=6 we can put 554 * ADDOFFSET to be from 0 to 2^k - 2^(11-k), and have 555 * OFFSET1==chunksize. For chunks of size 80 OFFSET1 of 2K%80=48 is 556 * large enough to have ADDOFFSET between 1 and 16 (similarly for 96, 557 * when ADDOFFSET should be 1). In particular, keeping MAGICs for 558 * these sizes gives no additional size penalty. 559 * 560 * However, for chunks of size 2^k with k<=5 this gives OFFSET1 >= 561 * ADDOFSET + 2^(11-k). Keeping ADDOFFSET 0 allows for 2^(11-k)-2^(11-2k) 562 * chunks per arena. This is smaller than 2^(11-k) - 1 which are 563 * needed if no MAGIC is kept. [In fact, having a negative ADDOFFSET 564 * would allow for slightly more buckets per arena for k=2,3.] 565 * 566 * Similarly, for chunks of size 3/2*2^k with k<=5 MAGICs would span 567 * the area up to 2^(11-k)+ADDOFFSET. For k=4 this give optimal 568 * ADDOFFSET as -7..0. For k=3 ADDOFFSET can go up to 4 (with tiny 569 * savings for negative ADDOFFSET). For k=5 ADDOFFSET can go -1..16 570 * (with no savings for negative values). 571 * 572 * In particular, keeping ADDOFFSET 0 for sizes of chunks up to 2^6 573 * leads to tiny pessimizations in case of sizes 4, 8, 12, 24, and 574 * leads to no contradictions except for size=80 (or 96.) 575 * 576 * However, it also makes sense to keep no magic for sizes 48 or less. 577 * This is what we do. In this case one needs ADDOFFSET>=1 also for 578 * chunksizes 12, 24, and 48, unless one gets one less chunk per 579 * arena. 580 * 581 * The algo of OV_MAGIC(block,bucket) keeps ADDOFFSET 0 until 582 * chunksize of 64, then makes it 1. 583 * 584 * This allows for an additional optimization: the above scheme leads 585 * to giant overheads for sizes 128 or more (one whole chunk needs to 586 * be sacrifised to keep INDEX). Instead we use chunks not of size 587 * 2^k, but of size 2^k-ALIGN. If we pack these chunks at the end of 588 * the arena, then the beginnings are still in different 2^k-long 589 * sections of the arena if k>=7 for ALIGN==4, and k>=8 if ALIGN=8. 590 * Thus for k>7 the above algo of calculating the offset of the magic 591 * will still give different answers for different chunks. And to 592 * avoid the overrun of MAGIC1 into INDEX, one needs ADDOFFSET of >=1. 593 * In the case k=7 we just move the first chunk an extra ALIGN 594 * backward inside the ARENA (this is done once per arena lifetime, 595 * thus is not a big overhead). */ 596 # define MAX_PACKED_POW2 6 597 # define MAX_PACKED (MAX_PACKED_POW2 * BUCKETS_PER_POW2 + BUCKET_POW2_SHIFT) 598 # define MAX_POW2_ALGO ((1<<(MAX_PACKED_POW2 + 1)) - M_OVERHEAD) 599 # define TWOK_MASK nBIT_MASK(LOG_OF_MIN_ARENA) 600 # define TWOK_MASKED(x) (PTR2UV(x) & ~TWOK_MASK) 601 # define TWOK_SHIFT(x) (PTR2UV(x) & TWOK_MASK) 602 # define OV_INDEXp(block) (INT2PTR(u_char*,TWOK_MASKED(block))) 603 # define OV_INDEX(block) (*OV_INDEXp(block)) 604 # define OV_MAGIC(block,bucket) (*(OV_INDEXp(block) + \ 605 (TWOK_SHIFT(block)>> \ 606 (bucket>>BUCKET_POW2_SHIFT)) + \ 607 (bucket >= MIN_NEEDS_SHIFT ? 1 : 0))) 608 /* A bucket can have a shift smaller than it size, we need to 609 shift its magic number so it will not overwrite index: */ 610 # ifdef BUCKETS_ROOT2 611 # define MIN_NEEDS_SHIFT (7*BUCKETS_PER_POW2 - 1) /* Shift 80 greater than chunk 64. */ 612 # else 613 # define MIN_NEEDS_SHIFT (7*BUCKETS_PER_POW2) /* Shift 128 greater than chunk 32. */ 614 # endif 615 # define CHUNK_SHIFT 0 616 617 /* Number of active buckets of given ordinal. */ 618 #ifdef IGNORE_SMALL_BAD_FREE 619 #define FIRST_BUCKET_WITH_CHECK (6 * BUCKETS_PER_POW2) /* 64 */ 620 # define N_BLKS(bucket) ( (bucket) < FIRST_BUCKET_WITH_CHECK \ 621 ? nBIT_MASK(LOG_OF_MIN_ARENA)/BUCKET_SIZE_NO_SURPLUS(bucket) \ 622 : n_blks[bucket] ) 623 #else 624 # define N_BLKS(bucket) n_blks[bucket] 625 #endif 626 627 static const u_short n_blks[LOG_OF_MIN_ARENA * BUCKETS_PER_POW2] = 628 { 629 # if BUCKETS_PER_POW2==1 630 0, 0, 631 (MIN_BUC_POW2==2 ? 384 : 0), 632 224, 120, 62, 31, 16, 8, 4, 2 633 # else 634 0, 0, 0, 0, 635 (MIN_BUC_POW2==2 ? 384 : 0), (MIN_BUC_POW2==2 ? 384 : 0), /* 4, 4 */ 636 224, 149, 120, 80, 62, 41, 31, 25, 16, 16, 8, 8, 4, 4, 2, 2 637 # endif 638 }; 639 640 /* Shift of the first bucket with the given ordinal inside 2K chunk. */ 641 #ifdef IGNORE_SMALL_BAD_FREE 642 # define BLK_SHIFT(bucket) ( (bucket) < FIRST_BUCKET_WITH_CHECK \ 643 ? ((1<<LOG_OF_MIN_ARENA) \ 644 - BUCKET_SIZE_NO_SURPLUS(bucket) * N_BLKS(bucket)) \ 645 : blk_shift[bucket]) 646 #else 647 # define BLK_SHIFT(bucket) blk_shift[bucket] 648 #endif 649 650 static const u_short blk_shift[LOG_OF_MIN_ARENA * BUCKETS_PER_POW2] = 651 { 652 # if BUCKETS_PER_POW2==1 653 0, 0, 654 (MIN_BUC_POW2==2 ? 512 : 0), 655 256, 128, 64, 64, /* 8 to 64 */ 656 16*sizeof(union overhead), 657 8*sizeof(union overhead), 658 4*sizeof(union overhead), 659 2*sizeof(union overhead), 660 # else 661 0, 0, 0, 0, 662 (MIN_BUC_POW2==2 ? 512 : 0), (MIN_BUC_POW2==2 ? 512 : 0), 663 256, 260, 128, 128, 64, 80, 64, 48, /* 8 to 96 */ 664 16*sizeof(union overhead), 16*sizeof(union overhead), 665 8*sizeof(union overhead), 8*sizeof(union overhead), 666 4*sizeof(union overhead), 4*sizeof(union overhead), 667 2*sizeof(union overhead), 2*sizeof(union overhead), 668 # endif 669 }; 670 671 # define NEEDED_ALIGNMENT 0x800 /* 2k boundaries */ 672 # define WANTED_ALIGNMENT 0x800 /* 2k boundaries */ 673 674 #else /* !PACK_MALLOC */ 675 676 # define OV_MAGIC(block,bucket) (block)->ov_magic 677 # define OV_INDEX(block) (block)->ov_index 678 # define CHUNK_SHIFT 1 679 # define MAX_PACKED -1 680 # define NEEDED_ALIGNMENT MEM_ALIGNBYTES 681 # define WANTED_ALIGNMENT 0x400 /* 1k boundaries */ 682 683 #endif /* !PACK_MALLOC */ 684 685 #define M_OVERHEAD (sizeof(union overhead) + RMAGIC_SZ) /* overhead at start+end */ 686 687 #ifdef PACK_MALLOC 688 # define MEM_OVERHEAD(bucket) \ 689 (bucket <= MAX_PACKED ? ((size_t)0) : M_OVERHEAD) 690 # ifdef SMALL_BUCKET_VIA_TABLE 691 # define START_SHIFTS_BUCKET ((MAX_PACKED_POW2 + 1) * BUCKETS_PER_POW2) 692 # define START_SHIFT MAX_PACKED_POW2 693 # ifdef BUCKETS_ROOT2 /* Chunks of size 3*2^n. */ 694 # define SIZE_TABLE_MAX 80 695 # else 696 # define SIZE_TABLE_MAX 64 697 # endif 698 static const char bucket_of[] = 699 { 700 # ifdef BUCKETS_ROOT2 /* Chunks of size 3*2^n. */ 701 /* 0 to 15 in 4-byte increments. */ 702 (sizeof(void*) > 4 ? 6 : 5), /* 4/8, 5-th bucket for better reports */ 703 6, /* 8 */ 704 IF_ALIGN_8(8,7), 8, /* 16/12, 16 */ 705 9, 9, 10, 10, /* 24, 32 */ 706 11, 11, 11, 11, /* 48 */ 707 12, 12, 12, 12, /* 64 */ 708 13, 13, 13, 13, /* 80 */ 709 13, 13, 13, 13 /* 80 */ 710 # else /* !BUCKETS_ROOT2 */ 711 /* 0 to 15 in 4-byte increments. */ 712 (sizeof(void*) > 4 ? 3 : 2), 713 3, 714 4, 4, 715 5, 5, 5, 5, 716 6, 6, 6, 6, 717 6, 6, 6, 6 718 # endif /* !BUCKETS_ROOT2 */ 719 }; 720 # else /* !SMALL_BUCKET_VIA_TABLE */ 721 # define START_SHIFTS_BUCKET MIN_BUCKET 722 # define START_SHIFT (MIN_BUC_POW2 - 1) 723 # endif /* !SMALL_BUCKET_VIA_TABLE */ 724 #else /* !PACK_MALLOC */ 725 # define MEM_OVERHEAD(bucket) M_OVERHEAD 726 # ifdef SMALL_BUCKET_VIA_TABLE 727 # undef SMALL_BUCKET_VIA_TABLE 728 # endif 729 # define START_SHIFTS_BUCKET MIN_BUCKET 730 # define START_SHIFT (MIN_BUC_POW2 - 1) 731 #endif /* !PACK_MALLOC */ 732 733 /* 734 * Big allocations are often of the size 2^n bytes. To make them a 735 * little bit better, make blocks of size 2^n+pagesize for big n. 736 */ 737 738 #ifdef TWO_POT_OPTIMIZE 739 740 # ifndef PERL_PAGESIZE 741 # define PERL_PAGESIZE 4096 742 # endif 743 # ifndef FIRST_BIG_POW2 744 # define FIRST_BIG_POW2 15 /* 32K, 16K is used too often. */ 745 # endif 746 # define FIRST_BIG_BLOCK (1<<FIRST_BIG_POW2) 747 /* If this value or more, check against bigger blocks. */ 748 # define FIRST_BIG_BOUND (FIRST_BIG_BLOCK - M_OVERHEAD) 749 /* If less than this value, goes into 2^n-overhead-block. */ 750 # define LAST_SMALL_BOUND ((FIRST_BIG_BLOCK>>1) - M_OVERHEAD) 751 752 # define POW2_OPTIMIZE_ADJUST(nbytes) \ 753 ((nbytes >= FIRST_BIG_BOUND) ? nbytes -= PERL_PAGESIZE : 0) 754 # define POW2_OPTIMIZE_SURPLUS(bucket) \ 755 ((size_t)((bucket >= FIRST_BIG_POW2 * BUCKETS_PER_POW2) ? PERL_PAGESIZE : 0)) 756 757 #else /* !TWO_POT_OPTIMIZE */ 758 # define POW2_OPTIMIZE_ADJUST(nbytes) 759 # define POW2_OPTIMIZE_SURPLUS(bucket) ((size_t)0) 760 #endif /* !TWO_POT_OPTIMIZE */ 761 762 #define BARK_64K_LIMIT(what,nbytes,size) 763 764 #ifndef MIN_SBRK 765 # define MIN_SBRK 2048 766 #endif 767 768 #ifndef FIRST_SBRK 769 # define FIRST_SBRK (48*1024) 770 #endif 771 772 /* Minimal sbrk in percents of what is already alloced. */ 773 #ifndef MIN_SBRK_FRAC 774 # define MIN_SBRK_FRAC 3 775 #endif 776 777 #ifndef SBRK_ALLOW_FAILURES 778 # define SBRK_ALLOW_FAILURES 3 779 #endif 780 781 #ifndef SBRK_FAILURE_PRICE 782 # define SBRK_FAILURE_PRICE 50 783 #endif 784 785 static void morecore (int bucket); 786 # if defined(DEBUGGING) 787 static void botch (const char *diag, const char *s, const char *file, int line); 788 # endif 789 static void add_to_chain (void *p, MEM_SIZE size, MEM_SIZE chip); 790 static void* get_from_chain (MEM_SIZE size); 791 static void* get_from_bigger_buckets(int bucket, MEM_SIZE size); 792 static union overhead *getpages (MEM_SIZE needed, int *nblksp, int bucket); 793 static int getpages_adjacent(MEM_SIZE require); 794 795 #ifdef I_MACH_CTHREADS 796 # undef MUTEX_LOCK 797 # define MUTEX_LOCK(m) STMT_START { if (*m) mutex_lock(*m); } STMT_END 798 # undef MUTEX_UNLOCK 799 # define MUTEX_UNLOCK(m) STMT_START { if (*m) mutex_unlock(*m); } STMT_END 800 #endif 801 802 #ifndef PTRSIZE 803 # define PTRSIZE sizeof(void*) 804 #endif 805 806 #ifndef BITS_IN_PTR 807 # define BITS_IN_PTR (8*PTRSIZE) 808 #endif 809 810 /* 811 * nextf[i] is the pointer to the next free block of size 2^i. The 812 * smallest allocatable block is 8 bytes. The overhead information 813 * precedes the data area returned to the user. 814 */ 815 #define NBUCKETS (BITS_IN_PTR*BUCKETS_PER_POW2 + 1) 816 static union overhead *nextf[NBUCKETS]; 817 818 #if defined(PURIFY) && !defined(USE_PERL_SBRK) 819 # define USE_PERL_SBRK 820 #endif 821 822 #ifdef USE_PERL_SBRK 823 # define sbrk(a) Perl_sbrk(a) 824 Malloc_t Perl_sbrk (int size); 825 #elif !defined(HAS_SBRK_PROTO) /* <unistd.h> usually takes care of this */ 826 extern Malloc_t sbrk(int); 827 #endif 828 829 #ifndef MIN_SBRK_FRAC1000 /* Backward compatibility */ 830 # define MIN_SBRK_FRAC1000 (MIN_SBRK_FRAC * 10) 831 #endif 832 833 #include "malloc_ctl.h" 834 835 #ifndef NO_MALLOC_DYNAMIC_CFG 836 # define PERL_MALLOC_OPT_CHARS "FMfAPGdac" 837 838 # ifndef FILL_DEAD_DEFAULT 839 # define FILL_DEAD_DEFAULT 1 840 # endif 841 # ifndef FILL_ALIVE_DEFAULT 842 # define FILL_ALIVE_DEFAULT 1 843 # endif 844 # ifndef FILL_CHECK_DEFAULT 845 # define FILL_CHECK_DEFAULT 1 846 # endif 847 848 static IV MallocCfg[MallocCfg_last] = { 849 FIRST_SBRK, 850 MIN_SBRK, 851 MIN_SBRK_FRAC, 852 SBRK_ALLOW_FAILURES, 853 SBRK_FAILURE_PRICE, 854 SBRK_ALLOW_FAILURES * SBRK_FAILURE_PRICE, /* sbrk_goodness */ 855 FILL_DEAD_DEFAULT, /* FILL_DEAD */ 856 FILL_ALIVE_DEFAULT, /* FILL_ALIVE */ 857 FILL_CHECK_DEFAULT, /* FILL_CHECK */ 858 0, /* MallocCfg_skip_cfg_env */ 859 0, /* MallocCfg_cfg_env_read */ 860 0, /* MallocCfg_emergency_buffer_size */ 861 0, /* MallocCfg_emergency_buffer_prepared_size */ 862 0 /* MallocCfg_emergency_buffer_last_req */ 863 }; 864 IV *MallocCfg_ptr = MallocCfg; 865 866 static char* MallocCfgP[MallocCfg_last] = { 867 0, /* MallocCfgP_emergency_buffer */ 868 0, /* MallocCfgP_emergency_buffer_prepared */ 869 }; 870 char **MallocCfgP_ptr = MallocCfgP; 871 872 # undef MIN_SBRK 873 # undef FIRST_SBRK 874 # undef MIN_SBRK_FRAC1000 875 # undef SBRK_ALLOW_FAILURES 876 # undef SBRK_FAILURE_PRICE 877 878 # define MIN_SBRK MallocCfg[MallocCfg_MIN_SBRK] 879 # define FIRST_SBRK MallocCfg[MallocCfg_FIRST_SBRK] 880 # define MIN_SBRK_FRAC1000 MallocCfg[MallocCfg_MIN_SBRK_FRAC1000] 881 # define SBRK_ALLOW_FAILURES MallocCfg[MallocCfg_SBRK_ALLOW_FAILURES] 882 # define SBRK_FAILURE_PRICE MallocCfg[MallocCfg_SBRK_FAILURE_PRICE] 883 884 # define sbrk_goodness MallocCfg[MallocCfg_sbrk_goodness] 885 886 # define emergency_buffer_size MallocCfg[MallocCfg_emergency_buffer_size] 887 # define emergency_buffer_last_req MallocCfg[MallocCfg_emergency_buffer_last_req] 888 889 # define FILL_DEAD MallocCfg[MallocCfg_filldead] 890 # define FILL_ALIVE MallocCfg[MallocCfg_fillalive] 891 # define FILL_CHECK_CFG MallocCfg[MallocCfg_fillcheck] 892 # define FILL_CHECK (FILL_DEAD && FILL_CHECK_CFG) 893 894 # define emergency_buffer MallocCfgP[MallocCfgP_emergency_buffer] 895 # define emergency_buffer_prepared MallocCfgP[MallocCfgP_emergency_buffer_prepared] 896 897 #else /* defined(NO_MALLOC_DYNAMIC_CFG) */ 898 899 # define FILL_DEAD 1 900 # define FILL_ALIVE 1 901 # define FILL_CHECK 1 902 static int sbrk_goodness = SBRK_ALLOW_FAILURES * SBRK_FAILURE_PRICE; 903 904 # define NO_PERL_MALLOC_ENV 905 906 #endif 907 908 #ifdef DEBUGGING_MSTATS 909 /* 910 * nmalloc[i] is the difference between the number of mallocs and frees 911 * for a given block size. 912 */ 913 static u_int nmalloc[NBUCKETS]; 914 static u_int sbrk_slack; 915 static u_int start_slack; 916 #else /* !( defined DEBUGGING_MSTATS ) */ 917 # define sbrk_slack 0 918 #endif 919 920 static u_int goodsbrk; 921 922 #ifdef PERL_EMERGENCY_SBRK 923 924 # ifndef BIG_SIZE 925 # define BIG_SIZE (1<<16) /* 64K */ 926 # endif 927 928 # ifdef NO_MALLOC_DYNAMIC_CFG 929 static MEM_SIZE emergency_buffer_size; 930 /* 0 if the last request for more memory succeeded. 931 Otherwise the size of the failing request. */ 932 static MEM_SIZE emergency_buffer_last_req; 933 static char *emergency_buffer; 934 static char *emergency_buffer_prepared; 935 # endif 936 937 # ifndef emergency_sbrk_croak 938 # define emergency_sbrk_croak croak2 939 # endif 940 941 static char * 942 perl_get_emergency_buffer(IV *size) 943 { 944 dTHX; 945 /* First offense, give a possibility to recover by dieing. */ 946 /* No malloc involved here: */ 947 SV *sv; 948 char *pv; 949 GV **gvp = (GV**)hv_fetchs(PL_defstash, "^M", FALSE); 950 951 if (!gvp) gvp = (GV**)hv_fetchs(PL_defstash, "\015", FALSE); 952 if (!gvp || !(sv = GvSV(*gvp)) || !SvPOK(sv) 953 || (SvLEN(sv) < (1<<LOG_OF_MIN_ARENA) - M_OVERHEAD)) 954 return NULL; /* Now die die die... */ 955 /* Got it, now detach SvPV: */ 956 pv = SvPV_nolen(sv); 957 /* Check alignment: */ 958 if ((PTR2UV(pv) - sizeof(union overhead)) & (NEEDED_ALIGNMENT - 1)) { 959 PerlIO_puts(PerlIO_stderr(),"Bad alignment of $^M!\n"); 960 return NULL; /* die die die */ 961 } 962 963 SvPOK_off(sv); 964 SvPV_set(sv, NULL); 965 SvCUR_set(sv, 0); 966 SvLEN_set(sv, 0); 967 *size = malloced_size(pv) + M_OVERHEAD; 968 return pv - sizeof(union overhead); 969 } 970 # define PERL_GET_EMERGENCY_BUFFER(p) perl_get_emergency_buffer(p) 971 972 # ifndef NO_MALLOC_DYNAMIC_CFG 973 static char * 974 get_emergency_buffer(IV *size) 975 { 976 char *pv = emergency_buffer_prepared; 977 978 *size = MallocCfg[MallocCfg_emergency_buffer_prepared_size]; 979 emergency_buffer_prepared = 0; 980 MallocCfg[MallocCfg_emergency_buffer_prepared_size] = 0; 981 return pv; 982 } 983 984 # define GET_EMERGENCY_BUFFER(p) get_emergency_buffer(p) 985 # else /* NO_MALLOC_DYNAMIC_CFG */ 986 # define GET_EMERGENCY_BUFFER(p) NULL 987 # endif 988 989 static Malloc_t 990 emergency_sbrk(MEM_SIZE size) 991 { 992 MEM_SIZE rsize = (((size - 1)>>LOG_OF_MIN_ARENA) + 1)<<LOG_OF_MIN_ARENA; 993 994 if (size >= BIG_SIZE 995 && (!emergency_buffer_last_req || 996 (size < (MEM_SIZE)emergency_buffer_last_req))) { 997 /* Give the possibility to recover, but avoid an infinite cycle. */ 998 MALLOC_UNLOCK; 999 emergency_buffer_last_req = size; 1000 emergency_sbrk_croak("Out of memory during \"large\" request for %" UVuf 1001 " bytes, total sbrk() is %" UVuf " bytes", 1002 (UV)size, (UV)(goodsbrk + sbrk_slack)); 1003 } 1004 1005 if ((MEM_SIZE)emergency_buffer_size >= rsize) { 1006 char *old = emergency_buffer; 1007 1008 emergency_buffer_size -= rsize; 1009 emergency_buffer += rsize; 1010 return old; 1011 } else { 1012 /* First offense, give a possibility to recover by dieing. */ 1013 /* No malloc involved here: */ 1014 IV Size; 1015 char *pv = GET_EMERGENCY_BUFFER(&Size); 1016 int have = 0; 1017 1018 if (emergency_buffer_size) { 1019 add_to_chain(emergency_buffer, emergency_buffer_size, 0); 1020 emergency_buffer_size = 0; 1021 emergency_buffer = NULL; 1022 have = 1; 1023 } 1024 1025 if (!pv) 1026 pv = PERL_GET_EMERGENCY_BUFFER(&Size); 1027 if (!pv) { 1028 if (have) 1029 goto do_croak; 1030 return (char *)-1; /* Now die die die... */ 1031 } 1032 1033 /* Check alignment: */ 1034 if (PTR2UV(pv) & (NEEDED_ALIGNMENT - 1)) { 1035 dTHX; 1036 1037 PerlIO_puts(PerlIO_stderr(),"Bad alignment of $^M!\n"); 1038 return (char *)-1; /* die die die */ 1039 } 1040 1041 emergency_buffer = pv; 1042 emergency_buffer_size = Size; 1043 } 1044 do_croak: 1045 MALLOC_UNLOCK; 1046 emergency_sbrk_croak("Out of memory during request for %" UVuf 1047 " bytes, total sbrk() is %" UVuf " bytes", 1048 (UV)size, (UV)(goodsbrk + sbrk_slack)); 1049 NOT_REACHED; /* NOTREACHED */ 1050 return NULL; 1051 } 1052 1053 #else /* !defined(PERL_EMERGENCY_SBRK) */ 1054 # define emergency_sbrk(size) -1 1055 #endif /* defined PERL_EMERGENCY_SBRK */ 1056 1057 /* Don't use PerlIO buffered writes as they allocate memory. */ 1058 #define MYMALLOC_WRITE2STDERR(s) PERL_UNUSED_RESULT(PerlLIO_write(PerlIO_fileno(PerlIO_stderr()),s,strlen(s))) 1059 1060 #ifdef DEBUGGING 1061 #undef ASSERT 1062 #define ASSERT(p,diag) if (!(p)) botch(diag,STRINGIFY(p),__FILE__,__LINE__); 1063 1064 static void 1065 botch(const char *diag, const char *s, const char *file, int line) 1066 { 1067 dTHX; 1068 if (!(PERL_MAYBE_ALIVE && PERL_GET_THX)) 1069 goto do_write; 1070 else { 1071 if (PerlIO_printf(PerlIO_stderr(), 1072 "assertion botched (%s?): %s %s:%d\n", 1073 diag, s, file, line) != 0) { 1074 do_write: /* Can be initializing interpreter */ 1075 MYMALLOC_WRITE2STDERR("assertion botched ("); 1076 MYMALLOC_WRITE2STDERR(diag); 1077 MYMALLOC_WRITE2STDERR("?): "); 1078 MYMALLOC_WRITE2STDERR(s); 1079 MYMALLOC_WRITE2STDERR(" ("); 1080 MYMALLOC_WRITE2STDERR(file); 1081 MYMALLOC_WRITE2STDERR(":"); 1082 { 1083 char linebuf[10]; 1084 char *s = linebuf + sizeof(linebuf) - 1; 1085 int n = line; 1086 *s = 0; 1087 do { 1088 *--s = '0' + (n % 10); 1089 } while (n /= 10); 1090 MYMALLOC_WRITE2STDERR(s); 1091 } 1092 MYMALLOC_WRITE2STDERR(")\n"); 1093 } 1094 PerlProc_abort(); 1095 } 1096 } 1097 #else 1098 #define ASSERT(p, diag) 1099 #endif 1100 1101 #ifdef MALLOC_FILL 1102 /* Fill should be long enough to cover long */ 1103 static void 1104 fill_pat_4bytes(unsigned char *s, size_t nbytes, const unsigned char *fill) 1105 { 1106 unsigned char *e = s + nbytes; 1107 long *lp; 1108 const long lfill = *(long*)fill; 1109 1110 if (PTR2UV(s) & (sizeof(long)-1)) { /* Align the pattern */ 1111 int shift = sizeof(long) - (PTR2UV(s) & (sizeof(long)-1)); 1112 unsigned const char *f = fill + sizeof(long) - shift; 1113 unsigned char *e1 = s + shift; 1114 1115 while (s < e1) 1116 *s++ = *f++; 1117 } 1118 lp = (long*)s; 1119 while ((unsigned char*)(lp + 1) <= e) 1120 *lp++ = lfill; 1121 s = (unsigned char*)lp; 1122 while (s < e) 1123 *s++ = *fill++; 1124 } 1125 /* Just malloc()ed */ 1126 static const unsigned char fill_feedadad[] = 1127 {0xFE, 0xED, 0xAD, 0xAD, 0xFE, 0xED, 0xAD, 0xAD, 1128 0xFE, 0xED, 0xAD, 0xAD, 0xFE, 0xED, 0xAD, 0xAD}; 1129 /* Just free()ed */ 1130 static const unsigned char fill_deadbeef[] = 1131 {0xDE, 0xAD, 0xBE, 0xEF, 0xDE, 0xAD, 0xBE, 0xEF, 1132 0xDE, 0xAD, 0xBE, 0xEF, 0xDE, 0xAD, 0xBE, 0xEF}; 1133 # define FILL_DEADBEEF(s, n) \ 1134 (void)(FILL_DEAD? (fill_pat_4bytes((s), (n), fill_deadbeef), 0) : 0) 1135 # define FILL_FEEDADAD(s, n) \ 1136 (void)(FILL_ALIVE? (fill_pat_4bytes((s), (n), fill_feedadad), 0) : 0) 1137 #else 1138 # define FILL_DEADBEEF(s, n) ((void)0) 1139 # define FILL_FEEDADAD(s, n) ((void)0) 1140 # undef MALLOC_FILL_CHECK 1141 #endif 1142 1143 #ifdef MALLOC_FILL_CHECK 1144 static int 1145 cmp_pat_4bytes(unsigned char *s, size_t nbytes, const unsigned char *fill) 1146 { 1147 unsigned char *e = s + nbytes; 1148 long *lp; 1149 const long lfill = *(long*)fill; 1150 1151 if (PTR2UV(s) & (sizeof(long)-1)) { /* Align the pattern */ 1152 int shift = sizeof(long) - (PTR2UV(s) & (sizeof(long)-1)); 1153 unsigned const char *f = fill + sizeof(long) - shift; 1154 unsigned char *e1 = s + shift; 1155 1156 while (s < e1) 1157 if (*s++ != *f++) 1158 return 1; 1159 } 1160 lp = (long*)s; 1161 while ((unsigned char*)(lp + 1) <= e) 1162 if (*lp++ != lfill) 1163 return 1; 1164 s = (unsigned char*)lp; 1165 while (s < e) 1166 if (*s++ != *fill++) 1167 return 1; 1168 return 0; 1169 } 1170 # define FILLCHECK_DEADBEEF(s, n) \ 1171 ASSERT(!FILL_CHECK || !cmp_pat_4bytes(s, n, fill_deadbeef), \ 1172 "free()ed/realloc()ed-away memory was overwritten") 1173 #else 1174 # define FILLCHECK_DEADBEEF(s, n) ((void)0) 1175 #endif 1176 1177 STATIC int 1178 S_adjust_size_and_find_bucket(size_t *nbytes_p) 1179 { 1180 MEM_SIZE shiftr; 1181 int bucket; 1182 size_t nbytes; 1183 1184 PERL_ARGS_ASSERT_ADJUST_SIZE_AND_FIND_BUCKET; 1185 1186 nbytes = *nbytes_p; 1187 1188 /* 1189 * Convert amount of memory requested into 1190 * closest block size stored in hash buckets 1191 * which satisfies request. Account for 1192 * space used per block for accounting. 1193 */ 1194 #ifdef PACK_MALLOC 1195 # ifdef SMALL_BUCKET_VIA_TABLE 1196 if (nbytes == 0) 1197 bucket = MIN_BUCKET; 1198 else if (nbytes <= SIZE_TABLE_MAX) { 1199 bucket = bucket_of[(nbytes - 1) >> BUCKET_TABLE_SHIFT]; 1200 } else 1201 # else 1202 if (nbytes == 0) 1203 nbytes = 1; 1204 if (nbytes <= MAX_POW2_ALGO) goto do_shifts; 1205 else 1206 # endif 1207 #endif 1208 { 1209 POW2_OPTIMIZE_ADJUST(nbytes); 1210 nbytes += M_OVERHEAD; 1211 nbytes = (nbytes + 3) &~ 3; 1212 #if defined(PACK_MALLOC) && !defined(SMALL_BUCKET_VIA_TABLE) 1213 do_shifts: 1214 #endif 1215 shiftr = (nbytes - 1) >> START_SHIFT; 1216 bucket = START_SHIFTS_BUCKET; 1217 /* apart from this loop, this is O(1) */ 1218 while (shiftr >>= 1) 1219 bucket += BUCKETS_PER_POW2; 1220 } 1221 *nbytes_p = nbytes; 1222 return bucket; 1223 } 1224 1225 /* 1226 =for apidoc malloc 1227 1228 Implements L<perlapi/C<Newx>> which you should use instead. 1229 1230 =cut 1231 */ 1232 1233 Malloc_t 1234 Perl_malloc(size_t nbytes) 1235 { 1236 union overhead *p; 1237 int bucket; 1238 #if defined(DEBUGGING) || defined(RCHECK) 1239 MEM_SIZE size = nbytes; 1240 #endif 1241 1242 /* A structure that has more than PTRDIFF_MAX bytes is unfortunately 1243 * legal in C, but in such, if two elements are far enough apart, we 1244 * can't legally find out how far apart they are. Limit the size of a 1245 * malloc so that pointer subtraction in the same structure is always 1246 * well defined */ 1247 if (nbytes > PTRDIFF_MAX) { 1248 dTHX; 1249 MYMALLOC_WRITE2STDERR("Memory requests are limited to PTRDIFF_MAX" 1250 " bytes to prevent possible undefined" 1251 " behavior"); 1252 return NULL; 1253 } 1254 1255 BARK_64K_LIMIT("Allocation",nbytes,nbytes); 1256 #ifdef DEBUGGING 1257 if ((long)nbytes < 0) 1258 croak("%s", "panic: malloc"); 1259 #endif 1260 1261 bucket = adjust_size_and_find_bucket(&nbytes); 1262 MALLOC_LOCK; 1263 /* 1264 * If nothing in hash bucket right now, 1265 * request more memory from the system. 1266 */ 1267 if (nextf[bucket] == NULL) 1268 morecore(bucket); 1269 if ((p = nextf[bucket]) == NULL) { 1270 MALLOC_UNLOCK; 1271 { 1272 dTHX; 1273 if (!PL_nomemok) { 1274 #if defined(PLAIN_MALLOC) && defined(NO_FANCY_MALLOC) 1275 MYMALLOC_WRITE2STDERR("Out of memory!\n"); 1276 #else 1277 char buff[80]; 1278 char *eb = buff + sizeof(buff) - 1; 1279 char *s = eb; 1280 size_t n = nbytes; 1281 1282 MYMALLOC_WRITE2STDERR("Out of memory during request for "); 1283 #if defined(DEBUGGING) || defined(RCHECK) 1284 n = size; 1285 #endif 1286 *s = 0; 1287 do { 1288 *--s = '0' + (n % 10); 1289 } while (n /= 10); 1290 MYMALLOC_WRITE2STDERR(s); 1291 MYMALLOC_WRITE2STDERR(" bytes, total sbrk() is "); 1292 s = eb; 1293 n = goodsbrk + sbrk_slack; 1294 do { 1295 *--s = '0' + (n % 10); 1296 } while (n /= 10); 1297 MYMALLOC_WRITE2STDERR(s); 1298 MYMALLOC_WRITE2STDERR(" bytes!\n"); 1299 #endif /* defined(PLAIN_MALLOC) && defined(NO_FANCY_MALLOC) */ 1300 my_exit(1); 1301 } 1302 } 1303 return (NULL); 1304 } 1305 1306 /* remove from linked list */ 1307 #ifdef DEBUGGING 1308 if ( (PTR2UV(p) & (MEM_ALIGNBYTES - 1)) 1309 /* Can't get this low */ 1310 || (p && PTR2UV(p) < (1<<LOG_OF_MIN_ARENA)) ) { 1311 dTHX; 1312 PerlIO_printf(PerlIO_stderr(), 1313 "Unaligned pointer in the free chain 0x%" UVxf "\n", 1314 PTR2UV(p)); 1315 } 1316 if ( (PTR2UV(p->ov_next) & (MEM_ALIGNBYTES - 1)) 1317 || (p->ov_next && PTR2UV(p->ov_next) < (1<<LOG_OF_MIN_ARENA)) ) { 1318 dTHX; 1319 PerlIO_printf(PerlIO_stderr(), 1320 "Unaligned \"next\" pointer in the free " 1321 "chain 0x%" UVxf " at 0x%" UVxf "\n", 1322 PTR2UV(p->ov_next), PTR2UV(p)); 1323 } 1324 #endif 1325 nextf[bucket] = p->ov_next; 1326 1327 MALLOC_UNLOCK; 1328 1329 DEBUG_m(PerlIO_printf(Perl_debug_log, 1330 "%p: (%05lu) malloc %ld bytes\n", 1331 (Malloc_t)(p + CHUNK_SHIFT), 1332 (unsigned long)(PL_an++), 1333 (long)size)); 1334 1335 FILLCHECK_DEADBEEF((unsigned char*)(p + CHUNK_SHIFT), 1336 BUCKET_SIZE_REAL(bucket) + RMAGIC_SZ); 1337 1338 #ifdef IGNORE_SMALL_BAD_FREE 1339 if (bucket >= FIRST_BUCKET_WITH_CHECK) 1340 #endif 1341 OV_MAGIC(p, bucket) = MAGIC; 1342 #ifndef PACK_MALLOC 1343 OV_INDEX(p) = bucket; 1344 #endif 1345 #ifdef RCHECK 1346 /* 1347 * Record allocated size of block and 1348 * bound space with magic numbers. 1349 */ 1350 p->ov_rmagic = RMAGIC; 1351 if (bucket <= MAX_SHORT_BUCKET) { 1352 int i; 1353 1354 nbytes = size + M_OVERHEAD; 1355 p->ov_size = nbytes - 1; 1356 if ((i = nbytes & (RMAGIC_SZ-1))) { 1357 i = RMAGIC_SZ - i; 1358 while (i--) /* nbytes - RMAGIC_SZ is end of alloced area */ 1359 ((caddr_t)p + nbytes - RMAGIC_SZ)[i] = RMAGIC_C; 1360 } 1361 /* Same at RMAGIC_SZ-aligned RMAGIC */ 1362 nbytes = (nbytes + RMAGIC_SZ - 1) & ~(RMAGIC_SZ - 1); 1363 ((u_int *)((caddr_t)p + nbytes))[-1] = RMAGIC; 1364 } 1365 FILL_FEEDADAD((unsigned char *)(p + CHUNK_SHIFT), size); 1366 #endif 1367 return ((Malloc_t)(p + CHUNK_SHIFT)); 1368 } 1369 1370 static char *last_sbrk_top; 1371 static char *last_op; /* This arena can be easily extended. */ 1372 static MEM_SIZE sbrked_remains; 1373 1374 #ifdef DEBUGGING_MSTATS 1375 static int sbrks; 1376 #endif 1377 1378 struct chunk_chain_s { 1379 struct chunk_chain_s *next; 1380 MEM_SIZE size; 1381 }; 1382 static struct chunk_chain_s *chunk_chain; 1383 static int n_chunks; 1384 static char max_bucket; 1385 1386 /* Cutoff a piece of one of the chunks in the chain. Prefer smaller chunk. */ 1387 static void * 1388 get_from_chain(MEM_SIZE size) 1389 { 1390 struct chunk_chain_s *elt = chunk_chain, **oldp = &chunk_chain; 1391 struct chunk_chain_s **oldgoodp = NULL; 1392 long min_remain = LONG_MAX; 1393 1394 while (elt) { 1395 if (elt->size >= size) { 1396 long remains = elt->size - size; 1397 if (remains >= 0 && remains < min_remain) { 1398 oldgoodp = oldp; 1399 min_remain = remains; 1400 } 1401 if (remains == 0) { 1402 break; 1403 } 1404 } 1405 oldp = &( elt->next ); 1406 elt = elt->next; 1407 } 1408 if (!oldgoodp) return NULL; 1409 if (min_remain) { 1410 void *ret = *oldgoodp; 1411 struct chunk_chain_s *next = (*oldgoodp)->next; 1412 1413 *oldgoodp = (struct chunk_chain_s *)((char*)ret + size); 1414 (*oldgoodp)->size = min_remain; 1415 (*oldgoodp)->next = next; 1416 return ret; 1417 } else { 1418 void *ret = *oldgoodp; 1419 *oldgoodp = (*oldgoodp)->next; 1420 n_chunks--; 1421 return ret; 1422 } 1423 } 1424 1425 static void 1426 add_to_chain(void *p, MEM_SIZE size, MEM_SIZE chip) 1427 { 1428 struct chunk_chain_s *next = chunk_chain; 1429 char *cp = (char*)p; 1430 1431 cp += chip; 1432 chunk_chain = (struct chunk_chain_s *)cp; 1433 chunk_chain->size = size - chip; 1434 chunk_chain->next = next; 1435 n_chunks++; 1436 } 1437 1438 static void * 1439 get_from_bigger_buckets(int bucket, MEM_SIZE size) 1440 { 1441 int price = 1; 1442 static int bucketprice[NBUCKETS]; 1443 while (bucket <= max_bucket) { 1444 /* We postpone stealing from bigger buckets until we want it 1445 often enough. */ 1446 if (nextf[bucket] && bucketprice[bucket]++ >= price) { 1447 /* Steal it! */ 1448 void *ret = (void*)(nextf[bucket] - 1 + CHUNK_SHIFT); 1449 bucketprice[bucket] = 0; 1450 if (((char*)nextf[bucket]) - M_OVERHEAD == last_op) { 1451 last_op = NULL; /* Disable optimization */ 1452 } 1453 nextf[bucket] = nextf[bucket]->ov_next; 1454 #ifdef DEBUGGING_MSTATS 1455 nmalloc[bucket]--; 1456 start_slack -= M_OVERHEAD; 1457 #endif 1458 add_to_chain(ret, (BUCKET_SIZE_NO_SURPLUS(bucket) + 1459 POW2_OPTIMIZE_SURPLUS(bucket)), 1460 size); 1461 return ret; 1462 } 1463 bucket++; 1464 } 1465 return NULL; 1466 } 1467 1468 static union overhead * 1469 getpages(MEM_SIZE needed, int *nblksp, int bucket) 1470 { 1471 /* Need to do (possibly expensive) system call. Try to 1472 optimize it for rare calling. */ 1473 MEM_SIZE require = needed - sbrked_remains; 1474 char *cp; 1475 union overhead *ovp; 1476 MEM_SIZE slack = 0; 1477 1478 if (sbrk_goodness > 0) { 1479 if (!last_sbrk_top && require < (MEM_SIZE)FIRST_SBRK) 1480 require = FIRST_SBRK; 1481 else if (require < (MEM_SIZE)MIN_SBRK) require = MIN_SBRK; 1482 1483 if (require < (Size_t)(goodsbrk * MIN_SBRK_FRAC1000 / 1000)) 1484 require = goodsbrk * MIN_SBRK_FRAC1000 / 1000; 1485 require = ((require - 1 + MIN_SBRK) / MIN_SBRK) * MIN_SBRK; 1486 } else { 1487 require = needed; 1488 last_sbrk_top = 0; 1489 sbrked_remains = 0; 1490 } 1491 1492 DEBUG_m(PerlIO_printf(Perl_debug_log, 1493 "sbrk(%ld) for %ld-byte-long arena\n", 1494 (long)require, (long) needed)); 1495 cp = (char *)sbrk(require); 1496 #ifdef DEBUGGING_MSTATS 1497 sbrks++; 1498 #endif 1499 if (cp == last_sbrk_top) { 1500 /* Common case, anything is fine. */ 1501 sbrk_goodness++; 1502 ovp = (union overhead *) (cp - sbrked_remains); 1503 last_op = cp - sbrked_remains; 1504 sbrked_remains = require - (needed - sbrked_remains); 1505 } else if (cp == (char *)-1) { /* no more room! */ 1506 ovp = (union overhead *)emergency_sbrk(needed); 1507 if (ovp == (union overhead *)-1) 1508 return 0; 1509 if (((char*)ovp) > last_op) { /* Cannot happen with current emergency_sbrk() */ 1510 last_op = 0; 1511 } 1512 return ovp; 1513 } else { /* Non-continuous or first sbrk(). */ 1514 long add = sbrked_remains; 1515 char *newcp; 1516 1517 if (sbrked_remains) { /* Put rest into chain, we 1518 cannot use it right now. */ 1519 add_to_chain((void*)(last_sbrk_top - sbrked_remains), 1520 sbrked_remains, 0); 1521 } 1522 1523 /* Second, check alignment. */ 1524 slack = 0; 1525 1526 /* WANTED_ALIGNMENT may be more than NEEDED_ALIGNMENT, but this may 1527 improve performance of memory access. */ 1528 if (PTR2UV(cp) & (WANTED_ALIGNMENT - 1)) { /* Not aligned. */ 1529 slack = WANTED_ALIGNMENT - (PTR2UV(cp) & (WANTED_ALIGNMENT - 1)); 1530 add += slack; 1531 } 1532 1533 if (add) { 1534 DEBUG_m(PerlIO_printf(Perl_debug_log, 1535 "sbrk(%ld) to fix non-continuous/off-page sbrk:\n\t%ld for alignment,\t%ld were assumed to come from the tail of the previous sbrk\n", 1536 (long)add, (long) slack, 1537 (long) sbrked_remains)); 1538 newcp = (char *)sbrk(add); 1539 #if defined(DEBUGGING_MSTATS) 1540 sbrks++; 1541 sbrk_slack += add; 1542 #endif 1543 if (newcp != cp + require) { 1544 /* Too bad: even rounding sbrk() is not continuous.*/ 1545 DEBUG_m(PerlIO_printf(Perl_debug_log, 1546 "failed to fix bad sbrk()\n")); 1547 #ifdef PACK_MALLOC 1548 if (slack) { 1549 MALLOC_UNLOCK; 1550 fatalcroak("panic: Off-page sbrk\n"); 1551 } 1552 #endif 1553 if (sbrked_remains) { 1554 /* Try again. */ 1555 #if defined(DEBUGGING_MSTATS) 1556 sbrk_slack += require; 1557 #endif 1558 require = needed; 1559 DEBUG_m(PerlIO_printf(Perl_debug_log, 1560 "straight sbrk(%ld)\n", 1561 (long)require)); 1562 cp = (char *)sbrk(require); 1563 #ifdef DEBUGGING_MSTATS 1564 sbrks++; 1565 #endif 1566 if (cp == (char *)-1) 1567 return 0; 1568 } 1569 sbrk_goodness = -1; /* Disable optimization! 1570 Continue with not-aligned... */ 1571 } else { 1572 cp += slack; 1573 require += sbrked_remains; 1574 } 1575 } 1576 1577 if (last_sbrk_top) { 1578 sbrk_goodness -= SBRK_FAILURE_PRICE; 1579 } 1580 1581 ovp = (union overhead *) cp; 1582 /* 1583 * Round up to minimum allocation size boundary 1584 * and deduct from block count to reflect. 1585 */ 1586 1587 # if NEEDED_ALIGNMENT > MEM_ALIGNBYTES 1588 if (PTR2UV(ovp) & (NEEDED_ALIGNMENT - 1)) 1589 fatalcroak("Misalignment of sbrk()\n"); 1590 else 1591 # endif 1592 if (PTR2UV(ovp) & (MEM_ALIGNBYTES - 1)) { 1593 DEBUG_m(PerlIO_printf(Perl_debug_log, 1594 "fixing sbrk(): %d bytes off machine alignment\n", 1595 (int)(PTR2UV(ovp) & (MEM_ALIGNBYTES - 1)))); 1596 ovp = INT2PTR(union overhead *,(PTR2UV(ovp) + MEM_ALIGNBYTES) & 1597 (MEM_ALIGNBYTES - 1)); 1598 (*nblksp)--; 1599 # if defined(DEBUGGING_MSTATS) 1600 /* This is only approx. if TWO_POT_OPTIMIZE: */ 1601 sbrk_slack += (1 << (bucket >> BUCKET_POW2_SHIFT)); 1602 # endif 1603 } 1604 ; /* Finish "else" */ 1605 sbrked_remains = require - needed; 1606 last_op = cp; 1607 } 1608 #if !defined(PLAIN_MALLOC) && !defined(NO_FANCY_MALLOC) 1609 emergency_buffer_last_req = 0; 1610 #endif 1611 last_sbrk_top = cp + require; 1612 #ifdef DEBUGGING_MSTATS 1613 goodsbrk += require; 1614 #endif 1615 return ovp; 1616 } 1617 1618 static int 1619 getpages_adjacent(MEM_SIZE require) 1620 { 1621 if (require <= sbrked_remains) { 1622 sbrked_remains -= require; 1623 } else { 1624 char *cp; 1625 1626 require -= sbrked_remains; 1627 /* We do not try to optimize sbrks here, we go for place. */ 1628 cp = (char*) sbrk(require); 1629 #ifdef DEBUGGING_MSTATS 1630 sbrks++; 1631 goodsbrk += require; 1632 #endif 1633 if (cp == last_sbrk_top) { 1634 sbrked_remains = 0; 1635 last_sbrk_top = cp + require; 1636 } else { 1637 if (cp == (char*)-1) { /* Out of memory */ 1638 #ifdef DEBUGGING_MSTATS 1639 goodsbrk -= require; 1640 #endif 1641 return 0; 1642 } 1643 /* Report the failure: */ 1644 if (sbrked_remains) 1645 add_to_chain((void*)(last_sbrk_top - sbrked_remains), 1646 sbrked_remains, 0); 1647 add_to_chain((void*)cp, require, 0); 1648 sbrk_goodness -= SBRK_FAILURE_PRICE; 1649 sbrked_remains = 0; 1650 last_sbrk_top = 0; 1651 last_op = 0; 1652 return 0; 1653 } 1654 } 1655 1656 return 1; 1657 } 1658 1659 /* 1660 * Allocate more memory to the indicated bucket. 1661 */ 1662 static void 1663 morecore(int bucket) 1664 { 1665 union overhead *ovp; 1666 int rnu; /* 2^rnu bytes will be requested */ 1667 int nblks; /* become nblks blocks of the desired size */ 1668 MEM_SIZE siz, needed; 1669 static int were_called = 0; 1670 1671 if (nextf[bucket]) 1672 return; 1673 #ifndef NO_PERL_MALLOC_ENV 1674 if (!were_called) { 1675 /* It's our first time. Initialize ourselves */ 1676 were_called = 1; /* Avoid a loop */ 1677 if (!MallocCfg[MallocCfg_skip_cfg_env]) { 1678 char *s = getenv("PERL_MALLOC_OPT"), *t = s; 1679 const char *off; 1680 const char *opts = PERL_MALLOC_OPT_CHARS; 1681 int changed = 0; 1682 1683 while ( t && t[0] && t[1] == '=' 1684 && ((off = strchr(opts, *t))) ) { 1685 IV val = 0; 1686 1687 t += 2; 1688 while (isDIGIT(*t)) 1689 val = 10*val + *t++ - '0'; 1690 if (!*t || *t == ';') { 1691 if (MallocCfg[off - opts] != val) 1692 changed = 1; 1693 MallocCfg[off - opts] = val; 1694 if (*t) 1695 t++; 1696 } 1697 } 1698 if (t && *t) { 1699 dTHX; 1700 MYMALLOC_WRITE2STDERR("Unrecognized part of PERL_MALLOC_OPT: \""); 1701 MYMALLOC_WRITE2STDERR(t); 1702 MYMALLOC_WRITE2STDERR("\"\n"); 1703 } 1704 if (changed) 1705 MallocCfg[MallocCfg_cfg_env_read] = 1; 1706 } 1707 } 1708 #endif 1709 if (bucket == sizeof(MEM_SIZE)*8*BUCKETS_PER_POW2) { 1710 MALLOC_UNLOCK; 1711 croak("%s", "Out of memory during ridiculously large request"); 1712 } 1713 if (bucket > max_bucket) 1714 max_bucket = bucket; 1715 1716 rnu = ( (bucket <= (LOG_OF_MIN_ARENA << BUCKET_POW2_SHIFT)) 1717 ? LOG_OF_MIN_ARENA 1718 : (bucket >> BUCKET_POW2_SHIFT) ); 1719 /* This may be overwritten later: */ 1720 nblks = 1 << (rnu - (bucket >> BUCKET_POW2_SHIFT)); /* how many blocks to get */ 1721 needed = ((MEM_SIZE)1 << rnu) + POW2_OPTIMIZE_SURPLUS(bucket); 1722 if (nextf[rnu << BUCKET_POW2_SHIFT]) { /* 2048b bucket. */ 1723 ovp = nextf[rnu << BUCKET_POW2_SHIFT] - 1 + CHUNK_SHIFT; 1724 nextf[rnu << BUCKET_POW2_SHIFT] 1725 = nextf[rnu << BUCKET_POW2_SHIFT]->ov_next; 1726 #ifdef DEBUGGING_MSTATS 1727 nmalloc[rnu << BUCKET_POW2_SHIFT]--; 1728 start_slack -= M_OVERHEAD; 1729 #endif 1730 DEBUG_m(PerlIO_printf(Perl_debug_log, 1731 "stealing %ld bytes from %ld arena\n", 1732 (long) needed, (long) rnu << BUCKET_POW2_SHIFT)); 1733 } else if (chunk_chain 1734 && (ovp = (union overhead*) get_from_chain(needed))) { 1735 DEBUG_m(PerlIO_printf(Perl_debug_log, 1736 "stealing %ld bytes from chain\n", 1737 (long) needed)); 1738 } else if ( (ovp = (union overhead*) 1739 get_from_bigger_buckets((rnu << BUCKET_POW2_SHIFT) + 1, 1740 needed)) ) { 1741 DEBUG_m(PerlIO_printf(Perl_debug_log, 1742 "stealing %ld bytes from bigger buckets\n", 1743 (long) needed)); 1744 } else if (needed <= sbrked_remains) { 1745 ovp = (union overhead *)(last_sbrk_top - sbrked_remains); 1746 sbrked_remains -= needed; 1747 last_op = (char*)ovp; 1748 } else 1749 ovp = getpages(needed, &nblks, bucket); 1750 1751 if (!ovp) 1752 return; 1753 FILL_DEADBEEF((unsigned char*)ovp, needed); 1754 1755 /* 1756 * Add new memory allocated to that on 1757 * free list for this hash bucket. 1758 */ 1759 siz = BUCKET_SIZE_NO_SURPLUS(bucket); /* No surplus if nblks > 1 */ 1760 #ifdef PACK_MALLOC 1761 *(u_char*)ovp = bucket; /* Fill index. */ 1762 if (bucket <= MAX_PACKED) { 1763 ovp = (union overhead *) ((char*)ovp + BLK_SHIFT(bucket)); 1764 nblks = N_BLKS(bucket); 1765 # ifdef DEBUGGING_MSTATS 1766 start_slack += BLK_SHIFT(bucket); 1767 # endif 1768 } else if (bucket < LOG_OF_MIN_ARENA * BUCKETS_PER_POW2) { 1769 ovp = (union overhead *) ((char*)ovp + BLK_SHIFT(bucket)); 1770 siz -= sizeof(union overhead); 1771 } else ovp++; /* One chunk per block. */ 1772 #endif /* PACK_MALLOC */ 1773 nextf[bucket] = ovp; 1774 #ifdef DEBUGGING_MSTATS 1775 nmalloc[bucket] += nblks; 1776 if (bucket > MAX_PACKED) { 1777 start_slack += M_OVERHEAD * nblks; 1778 } 1779 #endif 1780 1781 while (--nblks > 0) { 1782 ovp->ov_next = (union overhead *)((caddr_t)ovp + siz); 1783 ovp = (union overhead *)((caddr_t)ovp + siz); 1784 } 1785 /* Not all sbrks return zeroed memory.*/ 1786 ovp->ov_next = (union overhead *)NULL; 1787 #ifdef PACK_MALLOC 1788 if (bucket == 7*BUCKETS_PER_POW2) { /* Special case, explanation is above. */ 1789 union overhead *n_op = nextf[7*BUCKETS_PER_POW2]->ov_next; 1790 nextf[7*BUCKETS_PER_POW2] = 1791 (union overhead *)((caddr_t)nextf[7*BUCKETS_PER_POW2] 1792 - sizeof(union overhead)); 1793 nextf[7*BUCKETS_PER_POW2]->ov_next = n_op; 1794 } 1795 #endif /* !PACK_MALLOC */ 1796 } 1797 1798 /* 1799 =for apidoc mfree 1800 1801 Implements L<perlapi/C<Safefree>> which you should use instead. 1802 1803 =cut 1804 */ 1805 1806 Free_t 1807 Perl_mfree(Malloc_t where) 1808 { 1809 MEM_SIZE size; 1810 union overhead *ovp; 1811 char *cp = (char*)where; 1812 #ifdef PACK_MALLOC 1813 u_char bucket; 1814 #endif 1815 1816 DEBUG_m(PerlIO_printf(Perl_debug_log, 1817 "0x%" UVxf ": (%05lu) free\n", 1818 PTR2UV(cp), (unsigned long)(PL_an++))); 1819 1820 if (cp == NULL) 1821 return; 1822 #ifdef DEBUGGING 1823 if (PTR2UV(cp) & (MEM_ALIGNBYTES - 1)) 1824 croak("%s", "wrong alignment in free()"); 1825 #endif 1826 ovp = (union overhead *)((caddr_t)cp 1827 - sizeof (union overhead) * CHUNK_SHIFT); 1828 #ifdef PACK_MALLOC 1829 bucket = OV_INDEX(ovp); 1830 #endif 1831 #ifdef IGNORE_SMALL_BAD_FREE 1832 if ((bucket >= FIRST_BUCKET_WITH_CHECK) 1833 && (OV_MAGIC(ovp, bucket) != MAGIC)) 1834 #else 1835 if (OV_MAGIC(ovp, bucket) != MAGIC) 1836 #endif 1837 { 1838 static int bad_free_warn = -1; 1839 if (bad_free_warn == -1) { 1840 dTHX; 1841 char *pbf = PerlEnv_getenv("PERL_BADFREE"); 1842 bad_free_warn = (pbf) ? strNE("0", pbf) : 1; 1843 } 1844 if (!bad_free_warn) 1845 return; 1846 #ifdef RCHECK 1847 { 1848 dTHX; 1849 if (!PERL_IS_ALIVE || !PL_curcop) 1850 Perl_ck_warner_d(aTHX_ packWARN(WARN_MALLOC), "%s free() ignored (RMAGIC, PERL_CORE)", 1851 ovp->ov_rmagic == RMAGIC - 1 ? 1852 "Duplicate" : "Bad"); 1853 } 1854 #else 1855 { 1856 dTHX; 1857 if (!PERL_IS_ALIVE || !PL_curcop) 1858 Perl_ck_warner_d(aTHX_ packWARN(WARN_MALLOC), "%s", "Bad free() ignored (PERL_CORE)"); 1859 } 1860 #endif 1861 return; /* sanity */ 1862 } 1863 #ifdef RCHECK 1864 ASSERT(ovp->ov_rmagic == RMAGIC, "chunk's head overwrite"); 1865 if (OV_INDEX(ovp) <= MAX_SHORT_BUCKET) { 1866 int i; 1867 MEM_SIZE nbytes = ovp->ov_size + 1; 1868 1869 if ((i = nbytes & (RMAGIC_SZ-1))) { 1870 i = RMAGIC_SZ - i; 1871 while (i--) { /* nbytes - RMAGIC_SZ is end of alloced area */ 1872 ASSERT(((caddr_t)ovp + nbytes - RMAGIC_SZ)[i] == RMAGIC_C, 1873 "chunk's tail overwrite"); 1874 } 1875 } 1876 /* Same at RMAGIC_SZ-aligned RMAGIC */ 1877 nbytes = (nbytes + (RMAGIC_SZ-1)) & ~(RMAGIC_SZ-1); 1878 ASSERT(((u_int *)((caddr_t)ovp + nbytes))[-1] == RMAGIC, 1879 "chunk's tail overwrite"); 1880 FILLCHECK_DEADBEEF((unsigned char*)((caddr_t)ovp + nbytes), 1881 BUCKET_SIZE(OV_INDEX(ovp)) - nbytes); 1882 } 1883 FILL_DEADBEEF((unsigned char*)(ovp+CHUNK_SHIFT), 1884 BUCKET_SIZE_REAL(OV_INDEX(ovp)) + RMAGIC_SZ); 1885 ovp->ov_rmagic = RMAGIC - 1; 1886 #endif 1887 ASSERT(OV_INDEX(ovp) < NBUCKETS, "chunk's head overwrite"); 1888 size = OV_INDEX(ovp); 1889 1890 MALLOC_LOCK; 1891 ovp->ov_next = nextf[size]; 1892 nextf[size] = ovp; 1893 MALLOC_UNLOCK; 1894 } 1895 1896 /* 1897 =for apidoc realloc 1898 1899 Implements L<perlapi/C<Renew>> which you should use instead. 1900 1901 =cut 1902 */ 1903 1904 /* There is no need to do any locking in realloc (with an exception of 1905 trying to grow in place if we are at the end of the chain). 1906 If somebody calls us from a different thread with the same address, 1907 we are sole anyway. */ 1908 1909 Malloc_t 1910 Perl_realloc(void *mp, size_t nbytes) 1911 { 1912 MEM_SIZE onb; 1913 union overhead *ovp; 1914 char *res; 1915 int prev_bucket; 1916 int bucket; 1917 int incr; /* 1 if does not fit, -1 if "easily" fits in a 1918 smaller bucket, otherwise 0. */ 1919 char *cp = (char*)mp; 1920 1921 #ifdef DEBUGGING 1922 MEM_SIZE size = nbytes; 1923 1924 if ((long)nbytes < 0) 1925 croak("%s", "panic: realloc"); 1926 #endif 1927 1928 BARK_64K_LIMIT("Reallocation",nbytes,size); 1929 if (!cp) 1930 return Perl_malloc(nbytes); 1931 1932 ovp = (union overhead *)((caddr_t)cp 1933 - sizeof (union overhead) * CHUNK_SHIFT); 1934 bucket = OV_INDEX(ovp); 1935 1936 #ifdef IGNORE_SMALL_BAD_FREE 1937 if ((bucket >= FIRST_BUCKET_WITH_CHECK) 1938 && (OV_MAGIC(ovp, bucket) != MAGIC)) 1939 #else 1940 if (OV_MAGIC(ovp, bucket) != MAGIC) 1941 #endif 1942 { 1943 static int bad_free_warn = -1; 1944 if (bad_free_warn == -1) { 1945 dTHX; 1946 char *pbf = PerlEnv_getenv("PERL_BADFREE"); 1947 bad_free_warn = (pbf) ? strNE("0", pbf) : 1; 1948 } 1949 if (!bad_free_warn) 1950 return NULL; 1951 #ifdef RCHECK 1952 { 1953 dTHX; 1954 if (!PERL_IS_ALIVE || !PL_curcop) 1955 Perl_ck_warner_d(aTHX_ packWARN(WARN_MALLOC), "%srealloc() %signored", 1956 (ovp->ov_rmagic == RMAGIC - 1 ? "" : "Bad "), 1957 ovp->ov_rmagic == RMAGIC - 1 1958 ? "of freed memory " : ""); 1959 } 1960 #else 1961 { 1962 dTHX; 1963 if (!PERL_IS_ALIVE || !PL_curcop) 1964 Perl_ck_warner_d(aTHX_ packWARN(WARN_MALLOC), "%s", 1965 "Bad realloc() ignored"); 1966 } 1967 #endif 1968 return NULL; /* sanity */ 1969 } 1970 1971 onb = BUCKET_SIZE_REAL(bucket); 1972 /* 1973 * avoid the copy if same size block. 1974 * We are not aggressive with boundary cases. Note that it might 1975 * (for a small number of cases) give false negative if 1976 * both new size and old one are in the bucket for 1977 * FIRST_BIG_POW2, but the new one is near the lower end. 1978 * 1979 * We do not try to go to 1.5 times smaller bucket so far. 1980 */ 1981 if (nbytes > onb) incr = 1; 1982 else { 1983 #ifdef DO_NOT_TRY_HARDER_WHEN_SHRINKING 1984 if ( /* This is a little bit pessimal if PACK_MALLOC: */ 1985 nbytes > ( (onb >> 1) - M_OVERHEAD ) 1986 # ifdef TWO_POT_OPTIMIZE 1987 || (bucket == FIRST_BIG_POW2 && nbytes >= LAST_SMALL_BOUND ) 1988 # endif 1989 ) 1990 #else /* !DO_NOT_TRY_HARDER_WHEN_SHRINKING */ 1991 prev_bucket = ( (bucket > MAX_PACKED + 1) 1992 ? bucket - BUCKETS_PER_POW2 1993 : bucket - 1); 1994 if (nbytes > BUCKET_SIZE_REAL(prev_bucket)) 1995 #endif /* !DO_NOT_TRY_HARDER_WHEN_SHRINKING */ 1996 incr = 0; 1997 else incr = -1; 1998 } 1999 #ifdef STRESS_REALLOC 2000 goto hard_way; 2001 #endif 2002 if (incr == 0) { 2003 inplace_label: 2004 #ifdef RCHECK 2005 /* 2006 * Record new allocated size of block and 2007 * bound space with magic numbers. 2008 */ 2009 if (OV_INDEX(ovp) <= MAX_SHORT_BUCKET) { 2010 int i, nb = ovp->ov_size + 1; 2011 2012 if ((i = nb & (RMAGIC_SZ-1))) { 2013 i = RMAGIC_SZ - i; 2014 while (i--) { /* nb - RMAGIC_SZ is end of alloced area */ 2015 ASSERT(((caddr_t)ovp + nb - RMAGIC_SZ)[i] == RMAGIC_C, "chunk's tail overwrite"); 2016 } 2017 } 2018 /* Same at RMAGIC_SZ-aligned RMAGIC */ 2019 nb = (nb + (RMAGIC_SZ-1)) & ~(RMAGIC_SZ-1); 2020 ASSERT(((u_int *)((caddr_t)ovp + nb))[-1] == RMAGIC, 2021 "chunk's tail overwrite"); 2022 FILLCHECK_DEADBEEF((unsigned char*)((caddr_t)ovp + nb), 2023 BUCKET_SIZE(OV_INDEX(ovp)) - nb); 2024 if (nbytes > ovp->ov_size + 1 - M_OVERHEAD) 2025 FILL_FEEDADAD((unsigned char*)cp + ovp->ov_size + 1 - M_OVERHEAD, 2026 nbytes - (ovp->ov_size + 1 - M_OVERHEAD)); 2027 else 2028 FILL_DEADBEEF((unsigned char*)cp + nbytes, 2029 nb - M_OVERHEAD + RMAGIC_SZ - nbytes); 2030 /* 2031 * Convert amount of memory requested into 2032 * closest block size stored in hash buckets 2033 * which satisfies request. Account for 2034 * space used per block for accounting. 2035 */ 2036 nbytes += M_OVERHEAD; 2037 ovp->ov_size = nbytes - 1; 2038 if ((i = nbytes & (RMAGIC_SZ-1))) { 2039 i = RMAGIC_SZ - i; 2040 while (i--) /* nbytes - RMAGIC_SZ is end of alloced area */ 2041 ((caddr_t)ovp + nbytes - RMAGIC_SZ)[i] 2042 = RMAGIC_C; 2043 } 2044 /* Same at RMAGIC_SZ-aligned RMAGIC */ 2045 nbytes = (nbytes + (RMAGIC_SZ-1)) & ~(RMAGIC_SZ - 1); 2046 ((u_int *)((caddr_t)ovp + nbytes))[-1] = RMAGIC; 2047 } 2048 #endif 2049 res = cp; 2050 DEBUG_m(PerlIO_printf(Perl_debug_log, 2051 "0x%" UVxf ": (%05lu) realloc %ld bytes inplace\n", 2052 PTR2UV(res),(unsigned long)(PL_an++), 2053 (long)size)); 2054 } else if (incr == 1 && (cp - M_OVERHEAD == last_op) 2055 && (onb > (1 << LOG_OF_MIN_ARENA))) { 2056 MEM_SIZE require, newarena = nbytes, pow; 2057 int shiftr; 2058 2059 POW2_OPTIMIZE_ADJUST(newarena); 2060 newarena = newarena + M_OVERHEAD; 2061 /* newarena = (newarena + 3) &~ 3; */ 2062 shiftr = (newarena - 1) >> LOG_OF_MIN_ARENA; 2063 pow = LOG_OF_MIN_ARENA + 1; 2064 /* apart from this loop, this is O(1) */ 2065 while (shiftr >>= 1) 2066 pow++; 2067 newarena = (1 << pow) + POW2_OPTIMIZE_SURPLUS(pow * BUCKETS_PER_POW2); 2068 require = newarena - onb - M_OVERHEAD; 2069 2070 MALLOC_LOCK; 2071 if (cp - M_OVERHEAD == last_op /* We *still* are the last chunk */ 2072 && getpages_adjacent(require)) { 2073 #ifdef DEBUGGING_MSTATS 2074 nmalloc[bucket]--; 2075 nmalloc[pow * BUCKETS_PER_POW2]++; 2076 #endif 2077 if (pow * BUCKETS_PER_POW2 > (MEM_SIZE)max_bucket) 2078 max_bucket = pow * BUCKETS_PER_POW2; 2079 *(cp - M_OVERHEAD) = pow * BUCKETS_PER_POW2; /* Fill index. */ 2080 MALLOC_UNLOCK; 2081 goto inplace_label; 2082 } else { 2083 MALLOC_UNLOCK; 2084 goto hard_way; 2085 } 2086 } else { 2087 hard_way: 2088 DEBUG_m(PerlIO_printf(Perl_debug_log, 2089 "0x%" UVxf ": (%05lu) realloc %ld bytes the hard way\n", 2090 PTR2UV(cp),(unsigned long)(PL_an++), 2091 (long)size)); 2092 if ((res = (char*)Perl_malloc(nbytes)) == NULL) 2093 return (NULL); 2094 if (cp != res) /* common optimization */ 2095 Copy(cp, res, (MEM_SIZE)(nbytes<onb?nbytes:onb), char); 2096 Perl_mfree(cp); 2097 } 2098 return ((Malloc_t)res); 2099 } 2100 2101 /* 2102 =for apidoc calloc 2103 2104 Implements L<perlapi/C<Newxz>> which you should use instead. 2105 2106 =cut 2107 */ 2108 2109 Malloc_t 2110 Perl_calloc(size_t elements, size_t size) 2111 { 2112 long sz = elements * size; 2113 Malloc_t p = Perl_malloc(sz); 2114 2115 if (p) { 2116 memset((void*)p, 0, sz); 2117 } 2118 return p; 2119 } 2120 2121 char * 2122 Perl_strdup(const char *s) 2123 { 2124 MEM_SIZE l = strlen(s); 2125 char *s1 = (char *)Perl_malloc(l+1); 2126 2127 return (char *)CopyD(s, s1, (MEM_SIZE)(l+1), char); 2128 } 2129 2130 int 2131 Perl_putenv(char *a) 2132 { 2133 /* Sometimes system's putenv conflicts with my_setenv() - this is system 2134 malloc vs Perl's free(). */ 2135 dTHX; 2136 char *var; 2137 char *val = a; 2138 MEM_SIZE l; 2139 char buf[80]; 2140 2141 while (*val && *val != '=') 2142 val++; 2143 if (!*val) 2144 return -1; 2145 l = val - a; 2146 if (l < sizeof(buf)) 2147 var = buf; 2148 else 2149 var = (char *)Perl_malloc(l + 1); 2150 Copy(a, var, l, char); 2151 var[l + 1] = 0; 2152 my_setenv(var, val+1); 2153 if (var != buf) 2154 Perl_mfree(var); 2155 return 0; 2156 } 2157 2158 MEM_SIZE 2159 Perl_malloced_size(void *p) 2160 { 2161 union overhead * const ovp = (union overhead *) 2162 ((caddr_t)p - sizeof (union overhead) * CHUNK_SHIFT); 2163 const int bucket = OV_INDEX(ovp); 2164 2165 PERL_ARGS_ASSERT_MALLOCED_SIZE; 2166 2167 #ifdef RCHECK 2168 /* The caller wants to have a complete control over the chunk, 2169 disable the memory checking inside the chunk. */ 2170 if (bucket <= MAX_SHORT_BUCKET) { 2171 const MEM_SIZE size = BUCKET_SIZE_REAL(bucket); 2172 ovp->ov_size = size + M_OVERHEAD - 1; 2173 *((u_int *)((caddr_t)ovp + size + M_OVERHEAD - RMAGIC_SZ)) = RMAGIC; 2174 } 2175 #endif 2176 return BUCKET_SIZE_REAL(bucket); 2177 } 2178 2179 2180 MEM_SIZE 2181 Perl_malloc_good_size(size_t wanted) 2182 { 2183 return BUCKET_SIZE_REAL(adjust_size_and_find_bucket(&wanted)); 2184 } 2185 2186 # ifdef BUCKETS_ROOT2 2187 # define MIN_EVEN_REPORT 6 2188 # else 2189 # define MIN_EVEN_REPORT MIN_BUCKET 2190 # endif 2191 2192 int 2193 Perl_get_mstats(pTHX_ perl_mstats_t *buf, int buflen, int level) 2194 { 2195 #ifdef DEBUGGING_MSTATS 2196 int i, j; 2197 union overhead *p; 2198 struct chunk_chain_s* nextchain; 2199 2200 PERL_ARGS_ASSERT_GET_MSTATS; 2201 2202 buf->topbucket = buf->topbucket_ev = buf->topbucket_odd 2203 = buf->totfree = buf->total = buf->total_chain = 0; 2204 2205 buf->minbucket = MIN_BUCKET; 2206 MALLOC_LOCK; 2207 for (i = MIN_BUCKET ; i < NBUCKETS; i++) { 2208 for (j = 0, p = nextf[i]; p; p = p->ov_next, j++) 2209 ; 2210 if (i < buflen) { 2211 buf->nfree[i] = j; 2212 buf->ntotal[i] = nmalloc[i]; 2213 } 2214 buf->totfree += j * BUCKET_SIZE_REAL(i); 2215 buf->total += nmalloc[i] * BUCKET_SIZE_REAL(i); 2216 if (nmalloc[i]) { 2217 i % 2 ? (buf->topbucket_odd = i) : (buf->topbucket_ev = i); 2218 buf->topbucket = i; 2219 } 2220 } 2221 nextchain = chunk_chain; 2222 while (nextchain) { 2223 buf->total_chain += nextchain->size; 2224 nextchain = nextchain->next; 2225 } 2226 buf->total_sbrk = goodsbrk + sbrk_slack; 2227 buf->sbrks = sbrks; 2228 buf->sbrk_good = sbrk_goodness; 2229 buf->sbrk_slack = sbrk_slack; 2230 buf->start_slack = start_slack; 2231 buf->sbrked_remains = sbrked_remains; 2232 MALLOC_UNLOCK; 2233 buf->nbuckets = NBUCKETS; 2234 if (level) { 2235 for (i = MIN_BUCKET ; i < NBUCKETS; i++) { 2236 if (i >= buflen) 2237 break; 2238 buf->bucket_mem_size[i] = BUCKET_SIZE_NO_SURPLUS(i); 2239 buf->bucket_available_size[i] = BUCKET_SIZE_REAL(i); 2240 } 2241 } 2242 #else /* defined DEBUGGING_MSTATS */ 2243 PerlIO_printf(Perl_error_log, "perl not compiled with DEBUGGING_MSTATS\n"); 2244 #endif /* defined DEBUGGING_MSTATS */ 2245 return 0; /* XXX unused */ 2246 } 2247 2248 /* 2249 =for apidoc dump_mstats 2250 2251 When enabled by compiling with C<-DDEBUGGING_MSTATS>, print out statistics 2252 about malloc as two lines of numbers, one showing the length of the free list 2253 for each size category, the second showing the number of S<mallocs - frees> for 2254 each size category. 2255 2256 C<s>, if not NULL, is used as a phrase to include in the output, such as 2257 S<"after compilation">. 2258 2259 =cut 2260 */ 2261 2262 void 2263 Perl_dump_mstats(pTHX_ const char *s) 2264 { 2265 #ifdef DEBUGGING_MSTATS 2266 int i; 2267 perl_mstats_t buffer; 2268 UV nf[NBUCKETS]; 2269 UV nt[NBUCKETS]; 2270 2271 PERL_ARGS_ASSERT_DUMP_MSTATS; 2272 2273 buffer.nfree = nf; 2274 buffer.ntotal = nt; 2275 get_mstats(&buffer, NBUCKETS, 0); 2276 2277 if (s) 2278 PerlIO_printf(Perl_error_log, 2279 "Memory allocation statistics %s (buckets %" IVdf 2280 "(%" 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 2292 : " %" UVuf)), 2293 buffer.nfree[i]); 2294 } 2295 #ifdef BUCKETS_ROOT2 2296 PerlIO_printf(Perl_error_log, "\n\t "); 2297 for (i = MIN_BUCKET + 1; i <= buffer.topbucket_odd; i += BUCKETS_PER_POW2) { 2298 PerlIO_printf(Perl_error_log, 2299 ((i < 8*BUCKETS_PER_POW2 || i == 10*BUCKETS_PER_POW2) 2300 ? " %5"UVuf 2301 : ((i < 12*BUCKETS_PER_POW2) ? " %3"UVuf : " %"UVuf)), 2302 buffer.nfree[i]); 2303 } 2304 #endif 2305 PerlIO_printf(Perl_error_log, "\n%8" IVdf " used:", 2306 buffer.total - buffer.totfree); 2307 for (i = MIN_EVEN_REPORT; i <= buffer.topbucket; i += BUCKETS_PER_POW2) { 2308 PerlIO_printf(Perl_error_log, 2309 ((i < 8*BUCKETS_PER_POW2 || i == 10*BUCKETS_PER_POW2) 2310 ? " %5" IVdf 2311 : ((i < 12*BUCKETS_PER_POW2) ? " %3" IVdf : " %" IVdf)), 2312 buffer.ntotal[i] - buffer.nfree[i]); 2313 } 2314 #ifdef BUCKETS_ROOT2 2315 PerlIO_printf(Perl_error_log, "\n\t "); 2316 for (i = MIN_BUCKET + 1; i <= buffer.topbucket_odd; i += BUCKETS_PER_POW2) { 2317 PerlIO_printf(Perl_error_log, 2318 ((i < 8*BUCKETS_PER_POW2 || i == 10*BUCKETS_PER_POW2) 2319 ? " %5"IVdf 2320 : ((i < 12*BUCKETS_PER_POW2) ? " %3"IVdf : " %"IVdf)), 2321 buffer.ntotal[i] - buffer.nfree[i]); 2322 } 2323 #endif 2324 PerlIO_printf(Perl_error_log, "\nTotal sbrk(): %" IVdf "/%" IVdf ":%" 2325 IVdf ". Odd ends: pad+heads+chain+tail: %" IVdf "+%" 2326 IVdf "+%" IVdf "+%" IVdf ".\n", 2327 buffer.total_sbrk, buffer.sbrks, buffer.sbrk_good, 2328 buffer.sbrk_slack, buffer.start_slack, 2329 buffer.total_chain, buffer.sbrked_remains); 2330 #else /* DEBUGGING_MSTATS */ 2331 PerlIO_printf(Perl_error_log, "%s: perl not compiled with DEBUGGING_MSTATS\n",s); 2332 #endif /* DEBUGGING_MSTATS */ 2333 } 2334 2335 #ifdef USE_PERL_SBRK 2336 2337 # if defined(PURIFY) 2338 # define PERL_SBRK_VIA_MALLOC 2339 # endif 2340 2341 # ifdef PERL_SBRK_VIA_MALLOC 2342 2343 /* it may seem schizophrenic to use perl's malloc and let it call system */ 2344 /* malloc, the reason for that is only the 3.2 version of the OS that had */ 2345 /* frequent core dumps within nxzonefreenolock. This sbrk routine put an */ 2346 /* end to the cores */ 2347 2348 # ifndef SYSTEM_ALLOC 2349 # define SYSTEM_ALLOC(a) malloc(a) 2350 # endif 2351 # ifndef SYSTEM_ALLOC_ALIGNMENT 2352 # define SYSTEM_ALLOC_ALIGNMENT MEM_ALIGNBYTES 2353 # endif 2354 2355 # endif /* PERL_SBRK_VIA_MALLOC */ 2356 2357 static IV Perl_sbrk_oldchunk; 2358 static long Perl_sbrk_oldsize; 2359 2360 # define PERLSBRK_32_K (1<<15) 2361 # define PERLSBRK_64_K (1<<16) 2362 2363 Malloc_t 2364 Perl_sbrk(int size) 2365 { 2366 IV got; 2367 int small, reqsize; 2368 2369 if (!size) return 0; 2370 reqsize = size; /* just for the DEBUG_m statement */ 2371 #ifdef PACK_MALLOC 2372 size = (size + 0x7ff) & ~0x7ff; 2373 #endif 2374 if (size <= Perl_sbrk_oldsize) { 2375 got = Perl_sbrk_oldchunk; 2376 Perl_sbrk_oldchunk += size; 2377 Perl_sbrk_oldsize -= size; 2378 } else { 2379 if (size >= PERLSBRK_32_K) { 2380 small = 0; 2381 } else { 2382 size = PERLSBRK_64_K; 2383 small = 1; 2384 } 2385 # if NEEDED_ALIGNMENT > SYSTEM_ALLOC_ALIGNMENT 2386 size += NEEDED_ALIGNMENT - SYSTEM_ALLOC_ALIGNMENT; 2387 # endif 2388 got = (IV)SYSTEM_ALLOC(size); 2389 # if NEEDED_ALIGNMENT > SYSTEM_ALLOC_ALIGNMENT 2390 got = (got + NEEDED_ALIGNMENT - 1) & ~(NEEDED_ALIGNMENT - 1); 2391 # endif 2392 if (small) { 2393 /* Chunk is small, register the rest for future allocs. */ 2394 Perl_sbrk_oldchunk = got + reqsize; 2395 Perl_sbrk_oldsize = size - reqsize; 2396 } 2397 } 2398 2399 DEBUG_m(PerlIO_printf(Perl_debug_log, 2400 "sbrk malloc size %ld (reqsize %ld), left size %ld, give addr 0x%" 2401 UVxf "\n", 2402 size, reqsize, Perl_sbrk_oldsize, PTR2UV(got))); 2403 2404 return (void *)got; 2405 } 2406 2407 #endif /* ! defined USE_PERL_SBRK */ 2408 2409 /* 2410 * ex: set ts=8 sts=4 sw=4 et: 2411 */ 2412