| 1 | /* malloc.c |
| 2 | * |
| 3 | */ |
| 4 | |
| 5 | /* |
| 6 | Here are some notes on configuring Perl's malloc. |
| 7 | |
| 8 | There are two macros which serve as bulk disablers of advanced |
| 9 | features of this malloc: NO_FANCY_MALLOC, PLAIN_MALLOC (undef by |
| 10 | default). Look in the list of default values below to understand |
| 11 | their exact effect. Defining NO_FANCY_MALLOC returns malloc.c to the |
| 12 | state of the malloc in Perl 5.004. Additionally defining PLAIN_MALLOC |
| 13 | returns it to the state as of Perl 5.000. |
| 14 | |
| 15 | Note that some of the settings below may be ignored in the code based |
| 16 | on values of other macros. The PERL_CORE symbol is only defined when |
| 17 | perl itself is being compiled (so malloc can make some assumptions |
| 18 | about perl's facilities being available to it). |
| 19 | |
| 20 | Each config option has a short description, followed by its name, |
| 21 | default value, and a comment about the default (if applicable). Some |
| 22 | options take a precise value, while the others are just boolean. |
| 23 | The boolean ones are listed first. |
| 24 | |
| 25 | # Enable code for an emergency memory pool in $^M. See perlvar.pod |
| 26 | # for a description of $^M. |
| 27 | PERL_EMERGENCY_SBRK (!PLAIN_MALLOC && PERL_CORE) |
| 28 | |
| 29 | # Enable code for printing memory statistics. |
| 30 | DEBUGGING_MSTATS (!PLAIN_MALLOC && PERL_CORE) |
| 31 | |
| 32 | # Move allocation info for small buckets into separate areas. |
| 33 | # Memory optimization (especially for small allocations, of the |
| 34 | # less than 64 bytes). Since perl usually makes a large number |
| 35 | # of small allocations, this is usually a win. |
| 36 | PACK_MALLOC (!PLAIN_MALLOC && !RCHECK) |
| 37 | |
| 38 | # Add one page to big powers of two when calculating bucket size. |
| 39 | # This is targeted at big allocations, as are common in image |
| 40 | # processing. |
| 41 | TWO_POT_OPTIMIZE !PLAIN_MALLOC |
| 42 | |
| 43 | # Use intermediate bucket sizes between powers-of-two. This is |
| 44 | # generally a memory optimization, and a (small) speed pessimization. |
| 45 | BUCKETS_ROOT2 !NO_FANCY_MALLOC |
| 46 | |
| 47 | # Do not check small deallocations for bad free(). Memory |
| 48 | # and speed optimization, error reporting pessimization. |
| 49 | IGNORE_SMALL_BAD_FREE (!NO_FANCY_MALLOC && !RCHECK) |
| 50 | |
| 51 | # Use table lookup to decide in which bucket a given allocation will go. |
| 52 | SMALL_BUCKET_VIA_TABLE !NO_FANCY_MALLOC |
| 53 | |
| 54 | # Use a perl-defined sbrk() instead of the (presumably broken or |
| 55 | # missing) system-supplied sbrk(). |
| 56 | USE_PERL_SBRK undef |
| 57 | |
| 58 | # Use system malloc() (or calloc() etc.) to emulate sbrk(). Normally |
| 59 | # only used with broken sbrk()s. |
| 60 | PERL_SBRK_VIA_MALLOC undef |
| 61 | |
| 62 | # Which allocator to use if PERL_SBRK_VIA_MALLOC |
| 63 | SYSTEM_ALLOC(a) malloc(a) |
| 64 | |
| 65 | # Disable memory overwrite checking with DEBUGGING. Memory and speed |
| 66 | # optimization, error reporting pessimization. |
| 67 | NO_RCHECK undef |
| 68 | |
| 69 | # Enable memory overwrite checking with DEBUGGING. Memory and speed |
| 70 | # pessimization, error reporting optimization |
| 71 | RCHECK (DEBUGGING && !NO_RCHECK) |
| 72 | |
| 73 | # Failed allocations bigger than this size croak (if |
| 74 | # PERL_EMERGENCY_SBRK is enabled) without touching $^M. See |
| 75 | # perlvar.pod for a description of $^M. |
| 76 | BIG_SIZE (1<<16) # 64K |
| 77 | |
| 78 | # Starting from this power of two, add an extra page to the |
| 79 | # size of the bucket. This enables optimized allocations of sizes |
| 80 | # close to powers of 2. Note that the value is indexed at 0. |
| 81 | FIRST_BIG_POW2 15 # 32K, 16K is used too often |
| 82 | |
| 83 | # Estimate of minimal memory footprint. malloc uses this value to |
| 84 | # request the most reasonable largest blocks of memory from the system. |
| 85 | FIRST_SBRK (48*1024) |
| 86 | |
| 87 | # Round up sbrk()s to multiples of this. |
| 88 | MIN_SBRK 2048 |
| 89 | |
| 90 | # Round up sbrk()s to multiples of this percent of footprint. |
| 91 | MIN_SBRK_FRAC 3 |
| 92 | |
| 93 | # Add this much memory to big powers of two to get the bucket size. |
| 94 | PERL_PAGESIZE 4096 |
| 95 | |
| 96 | # This many sbrk() discontinuities should be tolerated even |
| 97 | # from the start without deciding that sbrk() is usually |
| 98 | # discontinuous. |
| 99 | SBRK_ALLOW_FAILURES 3 |
| 100 | |
| 101 | # This many continuous sbrk()s compensate for one discontinuous one. |
| 102 | SBRK_FAILURE_PRICE 50 |
| 103 | |
| 104 | This implementation assumes that calling PerlIO_printf() does not |
| 105 | result in any memory allocation calls (used during a panic). |
| 106 | |
| 107 | */ |
| 108 | |
| 109 | #ifndef NO_FANCY_MALLOC |
| 110 | # ifndef SMALL_BUCKET_VIA_TABLE |
| 111 | # define SMALL_BUCKET_VIA_TABLE |
| 112 | # endif |
| 113 | # ifndef BUCKETS_ROOT2 |
| 114 | # define BUCKETS_ROOT2 |
| 115 | # endif |
| 116 | # ifndef IGNORE_SMALL_BAD_FREE |
| 117 | # define IGNORE_SMALL_BAD_FREE |
| 118 | # endif |
| 119 | #endif |
| 120 | |
| 121 | #ifndef PLAIN_MALLOC /* Bulk enable features */ |
| 122 | # ifndef PACK_MALLOC |
| 123 | # define PACK_MALLOC |
| 124 | # endif |
| 125 | # ifndef TWO_POT_OPTIMIZE |
| 126 | # define TWO_POT_OPTIMIZE |
| 127 | # endif |
| 128 | # if defined(PERL_CORE) && !defined(PERL_EMERGENCY_SBRK) |
| 129 | # define PERL_EMERGENCY_SBRK |
| 130 | # endif |
| 131 | # if defined(PERL_CORE) && !defined(DEBUGGING_MSTATS) |
| 132 | # define DEBUGGING_MSTATS |
| 133 | # endif |
| 134 | #endif |
| 135 | |
| 136 | #define MIN_BUC_POW2 (sizeof(void*) > 4 ? 3 : 2) /* Allow for 4-byte arena. */ |
| 137 | #define MIN_BUCKET (MIN_BUC_POW2 * BUCKETS_PER_POW2) |
| 138 | |
| 139 | #if !(defined(I286) || defined(atarist)) |
| 140 | /* take 2k unless the block is bigger than that */ |
| 141 | # define LOG_OF_MIN_ARENA 11 |
| 142 | #else |
| 143 | /* take 16k unless the block is bigger than that |
| 144 | (80286s like large segments!), probably good on the atari too */ |
| 145 | # define LOG_OF_MIN_ARENA 14 |
| 146 | #endif |
| 147 | |
| 148 | #ifndef lint |
| 149 | # if defined(DEBUGGING) && !defined(NO_RCHECK) |
| 150 | # define RCHECK |
| 151 | # endif |
| 152 | # if defined(RCHECK) && defined(IGNORE_SMALL_BAD_FREE) |
| 153 | # undef IGNORE_SMALL_BAD_FREE |
| 154 | # endif |
| 155 | /* |
| 156 | * malloc.c (Caltech) 2/21/82 |
| 157 | * Chris Kingsley, kingsley@cit-20. |
| 158 | * |
| 159 | * This is a very fast storage allocator. It allocates blocks of a small |
| 160 | * number of different sizes, and keeps free lists of each size. Blocks that |
| 161 | * don't exactly fit are passed up to the next larger size. In this |
| 162 | * implementation, the available sizes are 2^n-4 (or 2^n-12) bytes long. |
| 163 | * If PACK_MALLOC is defined, small blocks are 2^n bytes long. |
| 164 | * This is designed for use in a program that uses vast quantities of memory, |
| 165 | * but bombs when it runs out. |
| 166 | */ |
| 167 | |
| 168 | #ifdef PERL_CORE |
| 169 | # include "EXTERN.h" |
| 170 | # include "perl.h" |
| 171 | #else |
| 172 | # ifdef PERL_FOR_X2P |
| 173 | # include "../EXTERN.h" |
| 174 | # include "../perl.h" |
| 175 | # else |
| 176 | # include <stdlib.h> |
| 177 | # include <stdio.h> |
| 178 | # include <memory.h> |
| 179 | # define _(arg) arg |
| 180 | # ifndef Malloc_t |
| 181 | # define Malloc_t void * |
| 182 | # endif |
| 183 | # ifndef MEM_SIZE |
| 184 | # define MEM_SIZE unsigned long |
| 185 | # endif |
| 186 | # ifndef LONG_MAX |
| 187 | # define LONG_MAX 0x7FFFFFFF |
| 188 | # endif |
| 189 | # ifndef UV |
| 190 | # define UV unsigned long |
| 191 | # endif |
| 192 | # ifndef caddr_t |
| 193 | # define caddr_t char * |
| 194 | # endif |
| 195 | # ifndef Free_t |
| 196 | # define Free_t void |
| 197 | # endif |
| 198 | # define Copy(s,d,n,t) (void)memcpy((char*)(d),(char*)(s), (n) * sizeof(t)) |
| 199 | # define PerlEnv_getenv getenv |
| 200 | # define PerlIO_printf fprintf |
| 201 | # define PerlIO_stderr() stderr |
| 202 | # endif |
| 203 | # ifndef croak /* make depend */ |
| 204 | # define croak(mess, arg) warn((mess), (arg)); exit(1); |
| 205 | # endif |
| 206 | # ifndef warn |
| 207 | # define warn(mess, arg) fprintf(stderr, (mess), (arg)); |
| 208 | # endif |
| 209 | # ifdef DEBUG_m |
| 210 | # undef DEBUG_m |
| 211 | # endif |
| 212 | # define DEBUG_m(a) |
| 213 | # ifdef DEBUGGING |
| 214 | # undef DEBUGGING |
| 215 | # endif |
| 216 | #endif |
| 217 | |
| 218 | #ifndef MUTEX_LOCK |
| 219 | # define MUTEX_LOCK(l) |
| 220 | #endif |
| 221 | |
| 222 | #ifndef MUTEX_UNLOCK |
| 223 | # define MUTEX_UNLOCK(l) |
| 224 | #endif |
| 225 | |
| 226 | #ifdef DEBUGGING |
| 227 | # undef DEBUG_m |
| 228 | # define DEBUG_m(a) if (debug & 128) a |
| 229 | #endif |
| 230 | |
| 231 | /* I don't much care whether these are defined in sys/types.h--LAW */ |
| 232 | |
| 233 | #define u_char unsigned char |
| 234 | #define u_int unsigned int |
| 235 | |
| 236 | #ifdef HAS_QUAD |
| 237 | # define u_bigint UV /* Needs to eat *void. */ |
| 238 | #else /* needed? */ |
| 239 | # define u_bigint unsigned long /* Needs to eat *void. */ |
| 240 | #endif |
| 241 | |
| 242 | #define u_short unsigned short |
| 243 | |
| 244 | /* 286 and atarist like big chunks, which gives too much overhead. */ |
| 245 | #if (defined(RCHECK) || defined(I286) || defined(atarist)) && defined(PACK_MALLOC) |
| 246 | # undef PACK_MALLOC |
| 247 | #endif |
| 248 | |
| 249 | /* |
| 250 | * The description below is applicable if PACK_MALLOC is not defined. |
| 251 | * |
| 252 | * The overhead on a block is at least 4 bytes. When free, this space |
| 253 | * contains a pointer to the next free block, and the bottom two bits must |
| 254 | * be zero. When in use, the first byte is set to MAGIC, and the second |
| 255 | * byte is the size index. The remaining bytes are for alignment. |
| 256 | * If range checking is enabled and the size of the block fits |
| 257 | * in two bytes, then the top two bytes hold the size of the requested block |
| 258 | * plus the range checking words, and the header word MINUS ONE. |
| 259 | */ |
| 260 | union overhead { |
| 261 | union overhead *ov_next; /* when free */ |
| 262 | #if MEM_ALIGNBYTES > 4 |
| 263 | double strut; /* alignment problems */ |
| 264 | #endif |
| 265 | struct { |
| 266 | u_char ovu_magic; /* magic number */ |
| 267 | u_char ovu_index; /* bucket # */ |
| 268 | #ifdef RCHECK |
| 269 | u_short ovu_size; /* actual block size */ |
| 270 | u_int ovu_rmagic; /* range magic number */ |
| 271 | #endif |
| 272 | } ovu; |
| 273 | #define ov_magic ovu.ovu_magic |
| 274 | #define ov_index ovu.ovu_index |
| 275 | #define ov_size ovu.ovu_size |
| 276 | #define ov_rmagic ovu.ovu_rmagic |
| 277 | }; |
| 278 | |
| 279 | #ifdef DEBUGGING |
| 280 | static void botch _((char *diag, char *s)); |
| 281 | #endif |
| 282 | static void morecore _((int bucket)); |
| 283 | static int findbucket _((union overhead *freep, int srchlen)); |
| 284 | |
| 285 | #define MAGIC 0xff /* magic # on accounting info */ |
| 286 | #define RMAGIC 0x55555555 /* magic # on range info */ |
| 287 | #define RMAGIC_C 0x55 /* magic # on range info */ |
| 288 | |
| 289 | #ifdef RCHECK |
| 290 | # define RSLOP sizeof (u_int) |
| 291 | # ifdef TWO_POT_OPTIMIZE |
| 292 | # define MAX_SHORT_BUCKET (12 * BUCKETS_PER_POW2) |
| 293 | # else |
| 294 | # define MAX_SHORT_BUCKET (13 * BUCKETS_PER_POW2) |
| 295 | # endif |
| 296 | #else |
| 297 | # define RSLOP 0 |
| 298 | #endif |
| 299 | |
| 300 | #if !defined(PACK_MALLOC) && defined(BUCKETS_ROOT2) |
| 301 | # undef BUCKETS_ROOT2 |
| 302 | #endif |
| 303 | |
| 304 | #ifdef BUCKETS_ROOT2 |
| 305 | # define BUCKET_TABLE_SHIFT 2 |
| 306 | # define BUCKET_POW2_SHIFT 1 |
| 307 | # define BUCKETS_PER_POW2 2 |
| 308 | #else |
| 309 | # define BUCKET_TABLE_SHIFT MIN_BUC_POW2 |
| 310 | # define BUCKET_POW2_SHIFT 0 |
| 311 | # define BUCKETS_PER_POW2 1 |
| 312 | #endif |
| 313 | |
| 314 | #if !defined(MEM_ALIGNBYTES) || ((MEM_ALIGNBYTES > 4) && !defined(STRICT_ALIGNMENT)) |
| 315 | /* Figure out the alignment of void*. */ |
| 316 | struct aligner { |
| 317 | char c; |
| 318 | void *p; |
| 319 | }; |
| 320 | # define ALIGN_SMALL ((int)((caddr_t)&(((struct aligner*)0)->p))) |
| 321 | #else |
| 322 | # define ALIGN_SMALL MEM_ALIGNBYTES |
| 323 | #endif |
| 324 | |
| 325 | #define IF_ALIGN_8(yes,no) ((ALIGN_SMALL>4) ? (yes) : (no)) |
| 326 | |
| 327 | #ifdef BUCKETS_ROOT2 |
| 328 | # define MAX_BUCKET_BY_TABLE 13 |
| 329 | static u_short buck_size[MAX_BUCKET_BY_TABLE + 1] = |
| 330 | { |
| 331 | 0, 0, 0, 0, 4, 4, 8, 12, 16, 24, 32, 48, 64, 80, |
| 332 | }; |
| 333 | # define BUCKET_SIZE(i) ((i) % 2 ? buck_size[i] : (1 << ((i) >> BUCKET_POW2_SHIFT))) |
| 334 | # define BUCKET_SIZE_REAL(i) ((i) <= MAX_BUCKET_BY_TABLE \ |
| 335 | ? buck_size[i] \ |
| 336 | : ((1 << ((i) >> BUCKET_POW2_SHIFT)) \ |
| 337 | - MEM_OVERHEAD(i) \ |
| 338 | + POW2_OPTIMIZE_SURPLUS(i))) |
| 339 | #else |
| 340 | # define BUCKET_SIZE(i) (1 << ((i) >> BUCKET_POW2_SHIFT)) |
| 341 | # define BUCKET_SIZE_REAL(i) (BUCKET_SIZE(i) - MEM_OVERHEAD(i) + POW2_OPTIMIZE_SURPLUS(i)) |
| 342 | #endif |
| 343 | |
| 344 | |
| 345 | #ifdef PACK_MALLOC |
| 346 | /* In this case it is assumed that if we do sbrk() in 2K units, we |
| 347 | * will get 2K aligned arenas (at least after some initial |
| 348 | * alignment). The bucket number of the given subblock is on the start |
| 349 | * of 2K arena which contains the subblock. Several following bytes |
| 350 | * contain the magic numbers for the subblocks in the block. |
| 351 | * |
| 352 | * Sizes of chunks are powers of 2 for chunks in buckets <= |
| 353 | * MAX_PACKED, after this they are (2^n - sizeof(union overhead)) (to |
| 354 | * get alignment right). |
| 355 | * |
| 356 | * Consider an arena for 2^n with n>MAX_PACKED. We suppose that |
| 357 | * starts of all the chunks in a 2K arena are in different |
| 358 | * 2^n-byte-long chunks. If the top of the last chunk is aligned on a |
| 359 | * boundary of 2K block, this means that sizeof(union |
| 360 | * overhead)*"number of chunks" < 2^n, or sizeof(union overhead)*2K < |
| 361 | * 4^n, or n > 6 + log2(sizeof()/2)/2, since a chunk of size 2^n - |
| 362 | * overhead is used. Since this rules out n = 7 for 8 byte alignment, |
| 363 | * we specialcase allocation of the first of 16 128-byte-long chunks. |
| 364 | * |
| 365 | * Note that with the above assumption we automatically have enough |
| 366 | * place for MAGIC at the start of 2K block. Note also that we |
| 367 | * overlay union overhead over the chunk, thus the start of small chunks |
| 368 | * is immediately overwritten after freeing. */ |
| 369 | # define MAX_PACKED_POW2 6 |
| 370 | # define MAX_PACKED (MAX_PACKED_POW2 * BUCKETS_PER_POW2 + BUCKET_POW2_SHIFT) |
| 371 | # define MAX_POW2_ALGO ((1<<(MAX_PACKED_POW2 + 1)) - M_OVERHEAD) |
| 372 | # define TWOK_MASK ((1<<LOG_OF_MIN_ARENA) - 1) |
| 373 | # define TWOK_MASKED(x) ((u_bigint)(x) & ~TWOK_MASK) |
| 374 | # define TWOK_SHIFT(x) ((u_bigint)(x) & TWOK_MASK) |
| 375 | # define OV_INDEXp(block) ((u_char*)(TWOK_MASKED(block))) |
| 376 | # define OV_INDEX(block) (*OV_INDEXp(block)) |
| 377 | # define OV_MAGIC(block,bucket) (*(OV_INDEXp(block) + \ |
| 378 | (TWOK_SHIFT(block)>> \ |
| 379 | (bucket>>BUCKET_POW2_SHIFT)) + \ |
| 380 | (bucket >= MIN_NEEDS_SHIFT ? 1 : 0))) |
| 381 | /* A bucket can have a shift smaller than it size, we need to |
| 382 | shift its magic number so it will not overwrite index: */ |
| 383 | # ifdef BUCKETS_ROOT2 |
| 384 | # define MIN_NEEDS_SHIFT (7*BUCKETS_PER_POW2 - 1) /* Shift 80 greater than chunk 64. */ |
| 385 | # else |
| 386 | # define MIN_NEEDS_SHIFT (7*BUCKETS_PER_POW2) /* Shift 128 greater than chunk 32. */ |
| 387 | # endif |
| 388 | # define CHUNK_SHIFT 0 |
| 389 | |
| 390 | /* Number of active buckets of given ordinal. */ |
| 391 | #ifdef IGNORE_SMALL_BAD_FREE |
| 392 | #define FIRST_BUCKET_WITH_CHECK (6 * BUCKETS_PER_POW2) /* 64 */ |
| 393 | # define N_BLKS(bucket) ( (bucket) < FIRST_BUCKET_WITH_CHECK \ |
| 394 | ? ((1<<LOG_OF_MIN_ARENA) - 1)/BUCKET_SIZE(bucket) \ |
| 395 | : n_blks[bucket] ) |
| 396 | #else |
| 397 | # define N_BLKS(bucket) n_blks[bucket] |
| 398 | #endif |
| 399 | |
| 400 | static u_short n_blks[LOG_OF_MIN_ARENA * BUCKETS_PER_POW2] = |
| 401 | { |
| 402 | # if BUCKETS_PER_POW2==1 |
| 403 | 0, 0, |
| 404 | (MIN_BUC_POW2==2 ? 384 : 0), |
| 405 | 224, 120, 62, 31, 16, 8, 4, 2 |
| 406 | # else |
| 407 | 0, 0, 0, 0, |
| 408 | (MIN_BUC_POW2==2 ? 384 : 0), (MIN_BUC_POW2==2 ? 384 : 0), /* 4, 4 */ |
| 409 | 224, 149, 120, 80, 62, 41, 31, 25, 16, 16, 8, 8, 4, 4, 2, 2 |
| 410 | # endif |
| 411 | }; |
| 412 | |
| 413 | /* Shift of the first bucket with the given ordinal inside 2K chunk. */ |
| 414 | #ifdef IGNORE_SMALL_BAD_FREE |
| 415 | # define BLK_SHIFT(bucket) ( (bucket) < FIRST_BUCKET_WITH_CHECK \ |
| 416 | ? ((1<<LOG_OF_MIN_ARENA) \ |
| 417 | - BUCKET_SIZE(bucket) * N_BLKS(bucket)) \ |
| 418 | : blk_shift[bucket]) |
| 419 | #else |
| 420 | # define BLK_SHIFT(bucket) blk_shift[bucket] |
| 421 | #endif |
| 422 | |
| 423 | static u_short blk_shift[LOG_OF_MIN_ARENA * BUCKETS_PER_POW2] = |
| 424 | { |
| 425 | # if BUCKETS_PER_POW2==1 |
| 426 | 0, 0, |
| 427 | (MIN_BUC_POW2==2 ? 512 : 0), |
| 428 | 256, 128, 64, 64, /* 8 to 64 */ |
| 429 | 16*sizeof(union overhead), |
| 430 | 8*sizeof(union overhead), |
| 431 | 4*sizeof(union overhead), |
| 432 | 2*sizeof(union overhead), |
| 433 | # else |
| 434 | 0, 0, 0, 0, |
| 435 | (MIN_BUC_POW2==2 ? 512 : 0), (MIN_BUC_POW2==2 ? 512 : 0), |
| 436 | 256, 260, 128, 128, 64, 80, 64, 48, /* 8 to 96 */ |
| 437 | 16*sizeof(union overhead), 16*sizeof(union overhead), |
| 438 | 8*sizeof(union overhead), 8*sizeof(union overhead), |
| 439 | 4*sizeof(union overhead), 4*sizeof(union overhead), |
| 440 | 2*sizeof(union overhead), 2*sizeof(union overhead), |
| 441 | # endif |
| 442 | }; |
| 443 | |
| 444 | #else /* !PACK_MALLOC */ |
| 445 | |
| 446 | # define OV_MAGIC(block,bucket) (block)->ov_magic |
| 447 | # define OV_INDEX(block) (block)->ov_index |
| 448 | # define CHUNK_SHIFT 1 |
| 449 | # define MAX_PACKED -1 |
| 450 | #endif /* !PACK_MALLOC */ |
| 451 | |
| 452 | #define M_OVERHEAD (sizeof(union overhead) + RSLOP) |
| 453 | |
| 454 | #ifdef PACK_MALLOC |
| 455 | # define MEM_OVERHEAD(bucket) \ |
| 456 | (bucket <= MAX_PACKED ? 0 : M_OVERHEAD) |
| 457 | # ifdef SMALL_BUCKET_VIA_TABLE |
| 458 | # define START_SHIFTS_BUCKET ((MAX_PACKED_POW2 + 1) * BUCKETS_PER_POW2) |
| 459 | # define START_SHIFT MAX_PACKED_POW2 |
| 460 | # ifdef BUCKETS_ROOT2 /* Chunks of size 3*2^n. */ |
| 461 | # define SIZE_TABLE_MAX 80 |
| 462 | # else |
| 463 | # define SIZE_TABLE_MAX 64 |
| 464 | # endif |
| 465 | static char bucket_of[] = |
| 466 | { |
| 467 | # ifdef BUCKETS_ROOT2 /* Chunks of size 3*2^n. */ |
| 468 | /* 0 to 15 in 4-byte increments. */ |
| 469 | (sizeof(void*) > 4 ? 6 : 5), /* 4/8, 5-th bucket for better reports */ |
| 470 | 6, /* 8 */ |
| 471 | IF_ALIGN_8(8,7), 8, /* 16/12, 16 */ |
| 472 | 9, 9, 10, 10, /* 24, 32 */ |
| 473 | 11, 11, 11, 11, /* 48 */ |
| 474 | 12, 12, 12, 12, /* 64 */ |
| 475 | 13, 13, 13, 13, /* 80 */ |
| 476 | 13, 13, 13, 13 /* 80 */ |
| 477 | # else /* !BUCKETS_ROOT2 */ |
| 478 | /* 0 to 15 in 4-byte increments. */ |
| 479 | (sizeof(void*) > 4 ? 3 : 2), |
| 480 | 3, |
| 481 | 4, 4, |
| 482 | 5, 5, 5, 5, |
| 483 | 6, 6, 6, 6, |
| 484 | 6, 6, 6, 6 |
| 485 | # endif /* !BUCKETS_ROOT2 */ |
| 486 | }; |
| 487 | # else /* !SMALL_BUCKET_VIA_TABLE */ |
| 488 | # define START_SHIFTS_BUCKET MIN_BUCKET |
| 489 | # define START_SHIFT (MIN_BUC_POW2 - 1) |
| 490 | # endif /* !SMALL_BUCKET_VIA_TABLE */ |
| 491 | #else /* !PACK_MALLOC */ |
| 492 | # define MEM_OVERHEAD(bucket) M_OVERHEAD |
| 493 | # ifdef SMALL_BUCKET_VIA_TABLE |
| 494 | # undef SMALL_BUCKET_VIA_TABLE |
| 495 | # endif |
| 496 | # define START_SHIFTS_BUCKET MIN_BUCKET |
| 497 | # define START_SHIFT (MIN_BUC_POW2 - 1) |
| 498 | #endif /* !PACK_MALLOC */ |
| 499 | |
| 500 | /* |
| 501 | * Big allocations are often of the size 2^n bytes. To make them a |
| 502 | * little bit better, make blocks of size 2^n+pagesize for big n. |
| 503 | */ |
| 504 | |
| 505 | #ifdef TWO_POT_OPTIMIZE |
| 506 | |
| 507 | # ifndef PERL_PAGESIZE |
| 508 | # define PERL_PAGESIZE 4096 |
| 509 | # endif |
| 510 | # ifndef FIRST_BIG_POW2 |
| 511 | # define FIRST_BIG_POW2 15 /* 32K, 16K is used too often. */ |
| 512 | # endif |
| 513 | # define FIRST_BIG_BLOCK (1<<FIRST_BIG_POW2) |
| 514 | /* If this value or more, check against bigger blocks. */ |
| 515 | # define FIRST_BIG_BOUND (FIRST_BIG_BLOCK - M_OVERHEAD) |
| 516 | /* If less than this value, goes into 2^n-overhead-block. */ |
| 517 | # define LAST_SMALL_BOUND ((FIRST_BIG_BLOCK>>1) - M_OVERHEAD) |
| 518 | |
| 519 | # define POW2_OPTIMIZE_ADJUST(nbytes) \ |
| 520 | ((nbytes >= FIRST_BIG_BOUND) ? nbytes -= PERL_PAGESIZE : 0) |
| 521 | # define POW2_OPTIMIZE_SURPLUS(bucket) \ |
| 522 | ((bucket >= FIRST_BIG_POW2 * BUCKETS_PER_POW2) ? PERL_PAGESIZE : 0) |
| 523 | |
| 524 | #else /* !TWO_POT_OPTIMIZE */ |
| 525 | # define POW2_OPTIMIZE_ADJUST(nbytes) |
| 526 | # define POW2_OPTIMIZE_SURPLUS(bucket) 0 |
| 527 | #endif /* !TWO_POT_OPTIMIZE */ |
| 528 | |
| 529 | #if defined(HAS_64K_LIMIT) && defined(PERL_CORE) |
| 530 | # define BARK_64K_LIMIT(what,nbytes,size) \ |
| 531 | if (nbytes > 0xffff) { \ |
| 532 | PerlIO_printf(PerlIO_stderr(), \ |
| 533 | "%s too large: %lx\n", what, size); \ |
| 534 | my_exit(1); \ |
| 535 | } |
| 536 | #else /* !HAS_64K_LIMIT || !PERL_CORE */ |
| 537 | # define BARK_64K_LIMIT(what,nbytes,size) |
| 538 | #endif /* !HAS_64K_LIMIT || !PERL_CORE */ |
| 539 | |
| 540 | #ifndef MIN_SBRK |
| 541 | # define MIN_SBRK 2048 |
| 542 | #endif |
| 543 | |
| 544 | #ifndef FIRST_SBRK |
| 545 | # define FIRST_SBRK (48*1024) |
| 546 | #endif |
| 547 | |
| 548 | /* Minimal sbrk in percents of what is already alloced. */ |
| 549 | #ifndef MIN_SBRK_FRAC |
| 550 | # define MIN_SBRK_FRAC 3 |
| 551 | #endif |
| 552 | |
| 553 | #ifndef SBRK_ALLOW_FAILURES |
| 554 | # define SBRK_ALLOW_FAILURES 3 |
| 555 | #endif |
| 556 | |
| 557 | #ifndef SBRK_FAILURE_PRICE |
| 558 | # define SBRK_FAILURE_PRICE 50 |
| 559 | #endif |
| 560 | |
| 561 | #if defined(PERL_EMERGENCY_SBRK) && defined(PERL_CORE) |
| 562 | |
| 563 | # ifndef BIG_SIZE |
| 564 | # define BIG_SIZE (1<<16) /* 64K */ |
| 565 | # endif |
| 566 | |
| 567 | static char *emergency_buffer; |
| 568 | static MEM_SIZE emergency_buffer_size; |
| 569 | |
| 570 | static Malloc_t |
| 571 | emergency_sbrk(size) |
| 572 | MEM_SIZE size; |
| 573 | { |
| 574 | if (size >= BIG_SIZE) { |
| 575 | /* Give the possibility to recover: */ |
| 576 | MUTEX_UNLOCK(&malloc_mutex); |
| 577 | croak("Out of memory during \"large\" request for %i bytes", size); |
| 578 | } |
| 579 | |
| 580 | if (!emergency_buffer) { |
| 581 | dTHR; |
| 582 | /* First offense, give a possibility to recover by dieing. */ |
| 583 | /* No malloc involved here: */ |
| 584 | GV **gvp = (GV**)hv_fetch(defstash, "^M", 2, 0); |
| 585 | SV *sv; |
| 586 | char *pv; |
| 587 | |
| 588 | if (!gvp) gvp = (GV**)hv_fetch(defstash, "\015", 1, 0); |
| 589 | if (!gvp || !(sv = GvSV(*gvp)) || !SvPOK(sv) |
| 590 | || (SvLEN(sv) < (1<<LOG_OF_MIN_ARENA) - M_OVERHEAD)) |
| 591 | return (char *)-1; /* Now die die die... */ |
| 592 | |
| 593 | /* Got it, now detach SvPV: */ |
| 594 | pv = SvPV(sv, na); |
| 595 | /* Check alignment: */ |
| 596 | if (((u_bigint)(pv - M_OVERHEAD)) & ((1<<LOG_OF_MIN_ARENA) - 1)) { |
| 597 | PerlIO_puts(PerlIO_stderr(),"Bad alignment of $^M!\n"); |
| 598 | return (char *)-1; /* die die die */ |
| 599 | } |
| 600 | |
| 601 | emergency_buffer = pv - M_OVERHEAD; |
| 602 | emergency_buffer_size = SvLEN(sv) + M_OVERHEAD; |
| 603 | SvPOK_off(sv); |
| 604 | SvREADONLY_on(sv); |
| 605 | MUTEX_UNLOCK(&malloc_mutex); |
| 606 | croak("Out of memory during request for %i bytes", size); |
| 607 | } |
| 608 | else if (emergency_buffer_size >= size) { |
| 609 | emergency_buffer_size -= size; |
| 610 | return emergency_buffer + emergency_buffer_size; |
| 611 | } |
| 612 | |
| 613 | return (char *)-1; /* poor guy... */ |
| 614 | } |
| 615 | |
| 616 | #else /* !(defined(PERL_EMERGENCY_SBRK) && defined(PERL_CORE)) */ |
| 617 | # define emergency_sbrk(size) -1 |
| 618 | #endif /* !(defined(PERL_EMERGENCY_SBRK) && defined(PERL_CORE)) */ |
| 619 | |
| 620 | /* |
| 621 | * nextf[i] is the pointer to the next free block of size 2^i. The |
| 622 | * smallest allocatable block is 8 bytes. The overhead information |
| 623 | * precedes the data area returned to the user. |
| 624 | */ |
| 625 | #define NBUCKETS (32*BUCKETS_PER_POW2 + 1) |
| 626 | static union overhead *nextf[NBUCKETS]; |
| 627 | |
| 628 | #ifdef USE_PERL_SBRK |
| 629 | #define sbrk(a) Perl_sbrk(a) |
| 630 | Malloc_t Perl_sbrk _((int size)); |
| 631 | #else |
| 632 | #ifdef DONT_DECLARE_STD |
| 633 | #ifdef I_UNISTD |
| 634 | #include <unistd.h> |
| 635 | #endif |
| 636 | #else |
| 637 | extern Malloc_t sbrk(int); |
| 638 | #endif |
| 639 | #endif |
| 640 | |
| 641 | #ifdef DEBUGGING_MSTATS |
| 642 | /* |
| 643 | * nmalloc[i] is the difference between the number of mallocs and frees |
| 644 | * for a given block size. |
| 645 | */ |
| 646 | static u_int nmalloc[NBUCKETS]; |
| 647 | static u_int sbrk_slack; |
| 648 | static u_int start_slack; |
| 649 | #endif |
| 650 | |
| 651 | static u_int goodsbrk; |
| 652 | |
| 653 | #ifdef DEBUGGING |
| 654 | #define ASSERT(p,diag) if (!(p)) botch(diag,STRINGIFY(p)); else |
| 655 | static void |
| 656 | botch(char *diag, char *s) |
| 657 | { |
| 658 | PerlIO_printf(PerlIO_stderr(), "assertion botched (%s?): %s\n", diag, s); |
| 659 | PerlProc_abort(); |
| 660 | } |
| 661 | #else |
| 662 | #define ASSERT(p, diag) |
| 663 | #endif |
| 664 | |
| 665 | Malloc_t |
| 666 | malloc(register size_t nbytes) |
| 667 | { |
| 668 | register union overhead *p; |
| 669 | register int bucket; |
| 670 | register MEM_SIZE shiftr; |
| 671 | |
| 672 | #if defined(DEBUGGING) || defined(RCHECK) |
| 673 | MEM_SIZE size = nbytes; |
| 674 | #endif |
| 675 | |
| 676 | BARK_64K_LIMIT("Allocation",nbytes,nbytes); |
| 677 | #ifdef DEBUGGING |
| 678 | if ((long)nbytes < 0) |
| 679 | croak("%s", "panic: malloc"); |
| 680 | #endif |
| 681 | |
| 682 | MUTEX_LOCK(&malloc_mutex); |
| 683 | /* |
| 684 | * Convert amount of memory requested into |
| 685 | * closest block size stored in hash buckets |
| 686 | * which satisfies request. Account for |
| 687 | * space used per block for accounting. |
| 688 | */ |
| 689 | #ifdef PACK_MALLOC |
| 690 | # ifdef SMALL_BUCKET_VIA_TABLE |
| 691 | if (nbytes == 0) |
| 692 | bucket = MIN_BUCKET; |
| 693 | else if (nbytes <= SIZE_TABLE_MAX) { |
| 694 | bucket = bucket_of[(nbytes - 1) >> BUCKET_TABLE_SHIFT]; |
| 695 | } else |
| 696 | # else |
| 697 | if (nbytes == 0) |
| 698 | nbytes = 1; |
| 699 | if (nbytes <= MAX_POW2_ALGO) goto do_shifts; |
| 700 | else |
| 701 | # endif |
| 702 | #endif |
| 703 | { |
| 704 | POW2_OPTIMIZE_ADJUST(nbytes); |
| 705 | nbytes += M_OVERHEAD; |
| 706 | nbytes = (nbytes + 3) &~ 3; |
| 707 | do_shifts: |
| 708 | shiftr = (nbytes - 1) >> START_SHIFT; |
| 709 | bucket = START_SHIFTS_BUCKET; |
| 710 | /* apart from this loop, this is O(1) */ |
| 711 | while (shiftr >>= 1) |
| 712 | bucket += BUCKETS_PER_POW2; |
| 713 | } |
| 714 | /* |
| 715 | * If nothing in hash bucket right now, |
| 716 | * request more memory from the system. |
| 717 | */ |
| 718 | if (nextf[bucket] == NULL) |
| 719 | morecore(bucket); |
| 720 | if ((p = nextf[bucket]) == NULL) { |
| 721 | MUTEX_UNLOCK(&malloc_mutex); |
| 722 | #ifdef PERL_CORE |
| 723 | if (!nomemok) { |
| 724 | PerlIO_puts(PerlIO_stderr(),"Out of memory!\n"); |
| 725 | my_exit(1); |
| 726 | } |
| 727 | #else |
| 728 | return (NULL); |
| 729 | #endif |
| 730 | } |
| 731 | |
| 732 | DEBUG_m(PerlIO_printf(Perl_debug_log, |
| 733 | "0x%lx: (%05lu) malloc %ld bytes\n", |
| 734 | (unsigned long)(p+1), (unsigned long)(an++), |
| 735 | (long)size)); |
| 736 | |
| 737 | /* remove from linked list */ |
| 738 | #if defined(RCHECK) |
| 739 | if (((UV)p) & (MEM_ALIGNBYTES - 1)) |
| 740 | PerlIO_printf(PerlIO_stderr(), "Corrupt malloc ptr 0x%lx at 0x%lx\n", |
| 741 | (unsigned long)*((int*)p),(unsigned long)p); |
| 742 | #endif |
| 743 | nextf[bucket] = p->ov_next; |
| 744 | #ifdef IGNORE_SMALL_BAD_FREE |
| 745 | if (bucket >= FIRST_BUCKET_WITH_CHECK) |
| 746 | #endif |
| 747 | OV_MAGIC(p, bucket) = MAGIC; |
| 748 | #ifndef PACK_MALLOC |
| 749 | OV_INDEX(p) = bucket; |
| 750 | #endif |
| 751 | #ifdef RCHECK |
| 752 | /* |
| 753 | * Record allocated size of block and |
| 754 | * bound space with magic numbers. |
| 755 | */ |
| 756 | p->ov_rmagic = RMAGIC; |
| 757 | if (bucket <= MAX_SHORT_BUCKET) { |
| 758 | int i; |
| 759 | |
| 760 | nbytes = size + M_OVERHEAD; |
| 761 | p->ov_size = nbytes - 1; |
| 762 | if ((i = nbytes & 3)) { |
| 763 | i = 4 - i; |
| 764 | while (i--) |
| 765 | *((char *)((caddr_t)p + nbytes - RSLOP + i)) = RMAGIC_C; |
| 766 | } |
| 767 | nbytes = (nbytes + 3) &~ 3; |
| 768 | *((u_int *)((caddr_t)p + nbytes - RSLOP)) = RMAGIC; |
| 769 | } |
| 770 | #endif |
| 771 | MUTEX_UNLOCK(&malloc_mutex); |
| 772 | return ((Malloc_t)(p + CHUNK_SHIFT)); |
| 773 | } |
| 774 | |
| 775 | static char *last_sbrk_top; |
| 776 | static char *last_op; /* This arena can be easily extended. */ |
| 777 | static int sbrked_remains; |
| 778 | static int sbrk_good = SBRK_ALLOW_FAILURES * SBRK_FAILURE_PRICE; |
| 779 | |
| 780 | #ifdef DEBUGGING_MSTATS |
| 781 | static int sbrks; |
| 782 | #endif |
| 783 | |
| 784 | struct chunk_chain_s { |
| 785 | struct chunk_chain_s *next; |
| 786 | MEM_SIZE size; |
| 787 | }; |
| 788 | static struct chunk_chain_s *chunk_chain; |
| 789 | static int n_chunks; |
| 790 | static char max_bucket; |
| 791 | |
| 792 | /* Cutoff a piece of one of the chunks in the chain. Prefer smaller chunk. */ |
| 793 | static void * |
| 794 | get_from_chain(MEM_SIZE size) |
| 795 | { |
| 796 | struct chunk_chain_s *elt = chunk_chain, **oldp = &chunk_chain; |
| 797 | struct chunk_chain_s **oldgoodp = NULL; |
| 798 | long min_remain = LONG_MAX; |
| 799 | |
| 800 | while (elt) { |
| 801 | if (elt->size >= size) { |
| 802 | long remains = elt->size - size; |
| 803 | if (remains >= 0 && remains < min_remain) { |
| 804 | oldgoodp = oldp; |
| 805 | min_remain = remains; |
| 806 | } |
| 807 | if (remains == 0) { |
| 808 | break; |
| 809 | } |
| 810 | } |
| 811 | oldp = &( elt->next ); |
| 812 | elt = elt->next; |
| 813 | } |
| 814 | if (!oldgoodp) return NULL; |
| 815 | if (min_remain) { |
| 816 | void *ret = *oldgoodp; |
| 817 | struct chunk_chain_s *next = (*oldgoodp)->next; |
| 818 | |
| 819 | *oldgoodp = (struct chunk_chain_s *)((char*)ret + size); |
| 820 | (*oldgoodp)->size = min_remain; |
| 821 | (*oldgoodp)->next = next; |
| 822 | return ret; |
| 823 | } else { |
| 824 | void *ret = *oldgoodp; |
| 825 | *oldgoodp = (*oldgoodp)->next; |
| 826 | n_chunks--; |
| 827 | return ret; |
| 828 | } |
| 829 | } |
| 830 | |
| 831 | static void |
| 832 | add_to_chain(void *p, MEM_SIZE size, MEM_SIZE chip) |
| 833 | { |
| 834 | struct chunk_chain_s *next = chunk_chain; |
| 835 | char *cp = (char*)p; |
| 836 | |
| 837 | cp += chip; |
| 838 | chunk_chain = (struct chunk_chain_s *)cp; |
| 839 | chunk_chain->size = size - chip; |
| 840 | chunk_chain->next = next; |
| 841 | n_chunks++; |
| 842 | } |
| 843 | |
| 844 | static void * |
| 845 | get_from_bigger_buckets(int bucket, MEM_SIZE size) |
| 846 | { |
| 847 | int price = 1; |
| 848 | static int bucketprice[NBUCKETS]; |
| 849 | while (bucket <= max_bucket) { |
| 850 | /* We postpone stealing from bigger buckets until we want it |
| 851 | often enough. */ |
| 852 | if (nextf[bucket] && bucketprice[bucket]++ >= price) { |
| 853 | /* Steal it! */ |
| 854 | void *ret = (void*)(nextf[bucket] - 1 + CHUNK_SHIFT); |
| 855 | bucketprice[bucket] = 0; |
| 856 | if (((char*)nextf[bucket]) - M_OVERHEAD == last_op) { |
| 857 | last_op = NULL; /* Disable optimization */ |
| 858 | } |
| 859 | nextf[bucket] = nextf[bucket]->ov_next; |
| 860 | #ifdef DEBUGGING_MSTATS |
| 861 | nmalloc[bucket]--; |
| 862 | start_slack -= M_OVERHEAD; |
| 863 | #endif |
| 864 | add_to_chain(ret, (BUCKET_SIZE(bucket) + |
| 865 | POW2_OPTIMIZE_SURPLUS(bucket)), |
| 866 | size); |
| 867 | return ret; |
| 868 | } |
| 869 | bucket++; |
| 870 | } |
| 871 | return NULL; |
| 872 | } |
| 873 | |
| 874 | static union overhead * |
| 875 | getpages(int needed, int *nblksp, int bucket) |
| 876 | { |
| 877 | /* Need to do (possibly expensive) system call. Try to |
| 878 | optimize it for rare calling. */ |
| 879 | MEM_SIZE require = needed - sbrked_remains; |
| 880 | char *cp; |
| 881 | union overhead *ovp; |
| 882 | int slack = 0; |
| 883 | |
| 884 | if (sbrk_good > 0) { |
| 885 | if (!last_sbrk_top && require < FIRST_SBRK) |
| 886 | require = FIRST_SBRK; |
| 887 | else if (require < MIN_SBRK) require = MIN_SBRK; |
| 888 | |
| 889 | if (require < goodsbrk * MIN_SBRK_FRAC / 100) |
| 890 | require = goodsbrk * MIN_SBRK_FRAC / 100; |
| 891 | require = ((require - 1 + MIN_SBRK) / MIN_SBRK) * MIN_SBRK; |
| 892 | } else { |
| 893 | require = needed; |
| 894 | last_sbrk_top = 0; |
| 895 | sbrked_remains = 0; |
| 896 | } |
| 897 | |
| 898 | DEBUG_m(PerlIO_printf(Perl_debug_log, |
| 899 | "sbrk(%ld) for %ld-byte-long arena\n", |
| 900 | (long)require, (long) needed)); |
| 901 | cp = (char *)sbrk(require); |
| 902 | #ifdef DEBUGGING_MSTATS |
| 903 | sbrks++; |
| 904 | #endif |
| 905 | if (cp == last_sbrk_top) { |
| 906 | /* Common case, anything is fine. */ |
| 907 | sbrk_good++; |
| 908 | ovp = (union overhead *) (cp - sbrked_remains); |
| 909 | sbrked_remains = require - (needed - sbrked_remains); |
| 910 | } else if (cp == (char *)-1) { /* no more room! */ |
| 911 | ovp = (union overhead *)emergency_sbrk(needed); |
| 912 | if (ovp == (union overhead *)-1) |
| 913 | return 0; |
| 914 | return ovp; |
| 915 | } else { /* Non-continuous or first sbrk(). */ |
| 916 | long add = sbrked_remains; |
| 917 | char *newcp; |
| 918 | |
| 919 | if (sbrked_remains) { /* Put rest into chain, we |
| 920 | cannot use it right now. */ |
| 921 | add_to_chain((void*)(last_sbrk_top - sbrked_remains), |
| 922 | sbrked_remains, 0); |
| 923 | } |
| 924 | |
| 925 | /* Second, check alignment. */ |
| 926 | slack = 0; |
| 927 | |
| 928 | #ifndef atarist /* on the atari we dont have to worry about this */ |
| 929 | # ifndef I286 /* The sbrk(0) call on the I286 always returns the next segment */ |
| 930 | |
| 931 | /* CHUNK_SHIFT is 1 for PACK_MALLOC, 0 otherwise. */ |
| 932 | if ((UV)cp & (0x7FF >> CHUNK_SHIFT)) { /* Not aligned. */ |
| 933 | slack = (0x800 >> CHUNK_SHIFT) |
| 934 | - ((UV)cp & (0x7FF >> CHUNK_SHIFT)); |
| 935 | add += slack; |
| 936 | } |
| 937 | # endif |
| 938 | #endif /* atarist */ |
| 939 | |
| 940 | if (add) { |
| 941 | DEBUG_m(PerlIO_printf(Perl_debug_log, |
| 942 | "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", |
| 943 | (long)add, (long) slack, |
| 944 | (long) sbrked_remains)); |
| 945 | newcp = (char *)sbrk(add); |
| 946 | #if defined(DEBUGGING_MSTATS) |
| 947 | sbrks++; |
| 948 | sbrk_slack += add; |
| 949 | #endif |
| 950 | if (newcp != cp + require) { |
| 951 | /* Too bad: even rounding sbrk() is not continuous.*/ |
| 952 | DEBUG_m(PerlIO_printf(Perl_debug_log, |
| 953 | "failed to fix bad sbrk()\n")); |
| 954 | #ifdef PACK_MALLOC |
| 955 | if (slack) { |
| 956 | MUTEX_UNLOCK(&malloc_mutex); |
| 957 | croak("%s", "panic: Off-page sbrk"); |
| 958 | } |
| 959 | #endif |
| 960 | if (sbrked_remains) { |
| 961 | /* Try again. */ |
| 962 | #if defined(DEBUGGING_MSTATS) |
| 963 | sbrk_slack += require; |
| 964 | #endif |
| 965 | require = needed; |
| 966 | DEBUG_m(PerlIO_printf(Perl_debug_log, |
| 967 | "straight sbrk(%ld)\n", |
| 968 | (long)require)); |
| 969 | cp = (char *)sbrk(require); |
| 970 | #ifdef DEBUGGING_MSTATS |
| 971 | sbrks++; |
| 972 | #endif |
| 973 | if (cp == (char *)-1) |
| 974 | return 0; |
| 975 | } |
| 976 | sbrk_good = -1; /* Disable optimization! |
| 977 | Continue with not-aligned... */ |
| 978 | } else { |
| 979 | cp += slack; |
| 980 | require += sbrked_remains; |
| 981 | } |
| 982 | } |
| 983 | |
| 984 | if (last_sbrk_top) { |
| 985 | sbrk_good -= SBRK_FAILURE_PRICE; |
| 986 | } |
| 987 | |
| 988 | ovp = (union overhead *) cp; |
| 989 | /* |
| 990 | * Round up to minimum allocation size boundary |
| 991 | * and deduct from block count to reflect. |
| 992 | */ |
| 993 | |
| 994 | #ifndef I286 /* Again, this should always be ok on an 80286 */ |
| 995 | if ((UV)ovp & 7) { |
| 996 | ovp = (union overhead *)(((UV)ovp + 8) & ~7); |
| 997 | DEBUG_m(PerlIO_printf(Perl_debug_log, |
| 998 | "fixing sbrk(): %d bytes off machine alignement\n", |
| 999 | (int)((UV)ovp & 7))); |
| 1000 | (*nblksp)--; |
| 1001 | # if defined(DEBUGGING_MSTATS) |
| 1002 | /* This is only approx. if TWO_POT_OPTIMIZE: */ |
| 1003 | sbrk_slack += (1 << bucket); |
| 1004 | # endif |
| 1005 | } |
| 1006 | #endif |
| 1007 | sbrked_remains = require - needed; |
| 1008 | } |
| 1009 | last_sbrk_top = cp + require; |
| 1010 | last_op = (char*) cp; |
| 1011 | #ifdef DEBUGGING_MSTATS |
| 1012 | goodsbrk += require; |
| 1013 | #endif |
| 1014 | return ovp; |
| 1015 | } |
| 1016 | |
| 1017 | static int |
| 1018 | getpages_adjacent(int require) |
| 1019 | { |
| 1020 | if (require <= sbrked_remains) { |
| 1021 | sbrked_remains -= require; |
| 1022 | } else { |
| 1023 | char *cp; |
| 1024 | |
| 1025 | require -= sbrked_remains; |
| 1026 | /* We do not try to optimize sbrks here, we go for place. */ |
| 1027 | cp = (char*) sbrk(require); |
| 1028 | #ifdef DEBUGGING_MSTATS |
| 1029 | sbrks++; |
| 1030 | goodsbrk += require; |
| 1031 | #endif |
| 1032 | if (cp == last_sbrk_top) { |
| 1033 | sbrked_remains = 0; |
| 1034 | last_sbrk_top = cp + require; |
| 1035 | } else { |
| 1036 | /* Report the failure: */ |
| 1037 | if (sbrked_remains) |
| 1038 | add_to_chain((void*)(last_sbrk_top - sbrked_remains), |
| 1039 | sbrked_remains, 0); |
| 1040 | add_to_chain((void*)cp, require, 0); |
| 1041 | sbrk_good -= SBRK_FAILURE_PRICE; |
| 1042 | sbrked_remains = 0; |
| 1043 | last_sbrk_top = 0; |
| 1044 | last_op = 0; |
| 1045 | return 0; |
| 1046 | } |
| 1047 | } |
| 1048 | |
| 1049 | return 1; |
| 1050 | } |
| 1051 | |
| 1052 | /* |
| 1053 | * Allocate more memory to the indicated bucket. |
| 1054 | */ |
| 1055 | static void |
| 1056 | morecore(register int bucket) |
| 1057 | { |
| 1058 | register union overhead *ovp; |
| 1059 | register int rnu; /* 2^rnu bytes will be requested */ |
| 1060 | int nblks; /* become nblks blocks of the desired size */ |
| 1061 | register MEM_SIZE siz, needed; |
| 1062 | |
| 1063 | if (nextf[bucket]) |
| 1064 | return; |
| 1065 | if (bucket == sizeof(MEM_SIZE)*8*BUCKETS_PER_POW2) { |
| 1066 | MUTEX_UNLOCK(&malloc_mutex); |
| 1067 | croak("%s", "Out of memory during ridiculously large request"); |
| 1068 | } |
| 1069 | if (bucket > max_bucket) |
| 1070 | max_bucket = bucket; |
| 1071 | |
| 1072 | rnu = ( (bucket <= (LOG_OF_MIN_ARENA << BUCKET_POW2_SHIFT)) |
| 1073 | ? LOG_OF_MIN_ARENA |
| 1074 | : (bucket >> BUCKET_POW2_SHIFT) ); |
| 1075 | /* This may be overwritten later: */ |
| 1076 | nblks = 1 << (rnu - (bucket >> BUCKET_POW2_SHIFT)); /* how many blocks to get */ |
| 1077 | needed = ((MEM_SIZE)1 << rnu) + POW2_OPTIMIZE_SURPLUS(bucket); |
| 1078 | if (nextf[rnu << BUCKET_POW2_SHIFT]) { /* 2048b bucket. */ |
| 1079 | ovp = nextf[rnu << BUCKET_POW2_SHIFT] - 1 + CHUNK_SHIFT; |
| 1080 | nextf[rnu << BUCKET_POW2_SHIFT] |
| 1081 | = nextf[rnu << BUCKET_POW2_SHIFT]->ov_next; |
| 1082 | #ifdef DEBUGGING_MSTATS |
| 1083 | nmalloc[rnu << BUCKET_POW2_SHIFT]--; |
| 1084 | start_slack -= M_OVERHEAD; |
| 1085 | #endif |
| 1086 | DEBUG_m(PerlIO_printf(Perl_debug_log, |
| 1087 | "stealing %ld bytes from %ld arena\n", |
| 1088 | (long) needed, (long) rnu << BUCKET_POW2_SHIFT)); |
| 1089 | } else if (chunk_chain |
| 1090 | && (ovp = (union overhead*) get_from_chain(needed))) { |
| 1091 | DEBUG_m(PerlIO_printf(Perl_debug_log, |
| 1092 | "stealing %ld bytes from chain\n", |
| 1093 | (long) needed)); |
| 1094 | } else if ( (ovp = (union overhead*) |
| 1095 | get_from_bigger_buckets((rnu << BUCKET_POW2_SHIFT) + 1, |
| 1096 | needed)) ) { |
| 1097 | DEBUG_m(PerlIO_printf(Perl_debug_log, |
| 1098 | "stealing %ld bytes from bigger buckets\n", |
| 1099 | (long) needed)); |
| 1100 | } else if (needed <= sbrked_remains) { |
| 1101 | ovp = (union overhead *)(last_sbrk_top - sbrked_remains); |
| 1102 | sbrked_remains -= needed; |
| 1103 | last_op = (char*)ovp; |
| 1104 | } else |
| 1105 | ovp = getpages(needed, &nblks, bucket); |
| 1106 | |
| 1107 | if (!ovp) |
| 1108 | return; |
| 1109 | |
| 1110 | /* |
| 1111 | * Add new memory allocated to that on |
| 1112 | * free list for this hash bucket. |
| 1113 | */ |
| 1114 | siz = BUCKET_SIZE(bucket); |
| 1115 | #ifdef PACK_MALLOC |
| 1116 | *(u_char*)ovp = bucket; /* Fill index. */ |
| 1117 | if (bucket <= MAX_PACKED) { |
| 1118 | ovp = (union overhead *) ((char*)ovp + BLK_SHIFT(bucket)); |
| 1119 | nblks = N_BLKS(bucket); |
| 1120 | # ifdef DEBUGGING_MSTATS |
| 1121 | start_slack += BLK_SHIFT(bucket); |
| 1122 | # endif |
| 1123 | } else if (bucket < LOG_OF_MIN_ARENA * BUCKETS_PER_POW2) { |
| 1124 | ovp = (union overhead *) ((char*)ovp + BLK_SHIFT(bucket)); |
| 1125 | siz -= sizeof(union overhead); |
| 1126 | } else ovp++; /* One chunk per block. */ |
| 1127 | #endif /* PACK_MALLOC */ |
| 1128 | nextf[bucket] = ovp; |
| 1129 | #ifdef DEBUGGING_MSTATS |
| 1130 | nmalloc[bucket] += nblks; |
| 1131 | if (bucket > MAX_PACKED) { |
| 1132 | start_slack += M_OVERHEAD * nblks; |
| 1133 | } |
| 1134 | #endif |
| 1135 | while (--nblks > 0) { |
| 1136 | ovp->ov_next = (union overhead *)((caddr_t)ovp + siz); |
| 1137 | ovp = (union overhead *)((caddr_t)ovp + siz); |
| 1138 | } |
| 1139 | /* Not all sbrks return zeroed memory.*/ |
| 1140 | ovp->ov_next = (union overhead *)NULL; |
| 1141 | #ifdef PACK_MALLOC |
| 1142 | if (bucket == 7*BUCKETS_PER_POW2) { /* Special case, explanation is above. */ |
| 1143 | union overhead *n_op = nextf[7*BUCKETS_PER_POW2]->ov_next; |
| 1144 | nextf[7*BUCKETS_PER_POW2] = |
| 1145 | (union overhead *)((caddr_t)nextf[7*BUCKETS_PER_POW2] |
| 1146 | - sizeof(union overhead)); |
| 1147 | nextf[7*BUCKETS_PER_POW2]->ov_next = n_op; |
| 1148 | } |
| 1149 | #endif /* !PACK_MALLOC */ |
| 1150 | } |
| 1151 | |
| 1152 | Free_t |
| 1153 | free(void *mp) |
| 1154 | { |
| 1155 | register MEM_SIZE size; |
| 1156 | register union overhead *ovp; |
| 1157 | char *cp = (char*)mp; |
| 1158 | #ifdef PACK_MALLOC |
| 1159 | u_char bucket; |
| 1160 | #endif |
| 1161 | |
| 1162 | DEBUG_m(PerlIO_printf(Perl_debug_log, |
| 1163 | "0x%lx: (%05lu) free\n", |
| 1164 | (unsigned long)cp, (unsigned long)(an++))); |
| 1165 | |
| 1166 | if (cp == NULL) |
| 1167 | return; |
| 1168 | ovp = (union overhead *)((caddr_t)cp |
| 1169 | - sizeof (union overhead) * CHUNK_SHIFT); |
| 1170 | #ifdef PACK_MALLOC |
| 1171 | bucket = OV_INDEX(ovp); |
| 1172 | #endif |
| 1173 | #ifdef IGNORE_SMALL_BAD_FREE |
| 1174 | if ((bucket >= FIRST_BUCKET_WITH_CHECK) |
| 1175 | && (OV_MAGIC(ovp, bucket) != MAGIC)) |
| 1176 | #else |
| 1177 | if (OV_MAGIC(ovp, bucket) != MAGIC) |
| 1178 | #endif |
| 1179 | { |
| 1180 | static int bad_free_warn = -1; |
| 1181 | if (bad_free_warn == -1) { |
| 1182 | char *pbf = PerlEnv_getenv("PERL_BADFREE"); |
| 1183 | bad_free_warn = (pbf) ? atoi(pbf) : 1; |
| 1184 | } |
| 1185 | if (!bad_free_warn) |
| 1186 | return; |
| 1187 | #ifdef RCHECK |
| 1188 | warn("%s free() ignored", |
| 1189 | ovp->ov_rmagic == RMAGIC - 1 ? "Duplicate" : "Bad"); |
| 1190 | #else |
| 1191 | warn("%s", "Bad free() ignored"); |
| 1192 | #endif |
| 1193 | return; /* sanity */ |
| 1194 | } |
| 1195 | MUTEX_LOCK(&malloc_mutex); |
| 1196 | #ifdef RCHECK |
| 1197 | ASSERT(ovp->ov_rmagic == RMAGIC, "chunk's head overwrite"); |
| 1198 | if (OV_INDEX(ovp) <= MAX_SHORT_BUCKET) { |
| 1199 | int i; |
| 1200 | MEM_SIZE nbytes = ovp->ov_size + 1; |
| 1201 | |
| 1202 | if ((i = nbytes & 3)) { |
| 1203 | i = 4 - i; |
| 1204 | while (i--) { |
| 1205 | ASSERT(*((char *)((caddr_t)ovp + nbytes - RSLOP + i)) |
| 1206 | == RMAGIC_C, "chunk's tail overwrite"); |
| 1207 | } |
| 1208 | } |
| 1209 | nbytes = (nbytes + 3) &~ 3; |
| 1210 | ASSERT(*(u_int *)((caddr_t)ovp + nbytes - RSLOP) == RMAGIC, "chunk's tail overwrite"); |
| 1211 | } |
| 1212 | ovp->ov_rmagic = RMAGIC - 1; |
| 1213 | #endif |
| 1214 | ASSERT(OV_INDEX(ovp) < NBUCKETS, "chunk's head overwrite"); |
| 1215 | size = OV_INDEX(ovp); |
| 1216 | ovp->ov_next = nextf[size]; |
| 1217 | nextf[size] = ovp; |
| 1218 | MUTEX_UNLOCK(&malloc_mutex); |
| 1219 | } |
| 1220 | |
| 1221 | /* |
| 1222 | * When a program attempts "storage compaction" as mentioned in the |
| 1223 | * old malloc man page, it realloc's an already freed block. Usually |
| 1224 | * this is the last block it freed; occasionally it might be farther |
| 1225 | * back. We have to search all the free lists for the block in order |
| 1226 | * to determine its bucket: 1st we make one pass thru the lists |
| 1227 | * checking only the first block in each; if that fails we search |
| 1228 | * ``reall_srchlen'' blocks in each list for a match (the variable |
| 1229 | * is extern so the caller can modify it). If that fails we just copy |
| 1230 | * however many bytes was given to realloc() and hope it's not huge. |
| 1231 | */ |
| 1232 | int reall_srchlen = 4; /* 4 should be plenty, -1 =>'s whole list */ |
| 1233 | |
| 1234 | Malloc_t |
| 1235 | realloc(void *mp, size_t nbytes) |
| 1236 | { |
| 1237 | register MEM_SIZE onb; |
| 1238 | union overhead *ovp; |
| 1239 | char *res; |
| 1240 | int prev_bucket; |
| 1241 | register int bucket; |
| 1242 | int was_alloced = 0, incr; |
| 1243 | char *cp = (char*)mp; |
| 1244 | |
| 1245 | #if defined(DEBUGGING) || !defined(PERL_CORE) |
| 1246 | MEM_SIZE size = nbytes; |
| 1247 | |
| 1248 | if ((long)nbytes < 0) |
| 1249 | croak("%s", "panic: realloc"); |
| 1250 | #endif |
| 1251 | |
| 1252 | BARK_64K_LIMIT("Reallocation",nbytes,size); |
| 1253 | if (!cp) |
| 1254 | return malloc(nbytes); |
| 1255 | |
| 1256 | MUTEX_LOCK(&malloc_mutex); |
| 1257 | ovp = (union overhead *)((caddr_t)cp |
| 1258 | - sizeof (union overhead) * CHUNK_SHIFT); |
| 1259 | bucket = OV_INDEX(ovp); |
| 1260 | #ifdef IGNORE_SMALL_BAD_FREE |
| 1261 | if ((bucket < FIRST_BUCKET_WITH_CHECK) |
| 1262 | || (OV_MAGIC(ovp, bucket) == MAGIC)) |
| 1263 | #else |
| 1264 | if (OV_MAGIC(ovp, bucket) == MAGIC) |
| 1265 | #endif |
| 1266 | { |
| 1267 | was_alloced = 1; |
| 1268 | } else { |
| 1269 | /* |
| 1270 | * Already free, doing "compaction". |
| 1271 | * |
| 1272 | * Search for the old block of memory on the |
| 1273 | * free list. First, check the most common |
| 1274 | * case (last element free'd), then (this failing) |
| 1275 | * the last ``reall_srchlen'' items free'd. |
| 1276 | * If all lookups fail, then assume the size of |
| 1277 | * the memory block being realloc'd is the |
| 1278 | * smallest possible. |
| 1279 | */ |
| 1280 | if ((bucket = findbucket(ovp, 1)) < 0 && |
| 1281 | (bucket = findbucket(ovp, reall_srchlen)) < 0) |
| 1282 | bucket = 0; |
| 1283 | } |
| 1284 | onb = BUCKET_SIZE_REAL(bucket); |
| 1285 | /* |
| 1286 | * avoid the copy if same size block. |
| 1287 | * We are not agressive with boundary cases. Note that it might |
| 1288 | * (for a small number of cases) give false negative if |
| 1289 | * both new size and old one are in the bucket for |
| 1290 | * FIRST_BIG_POW2, but the new one is near the lower end. |
| 1291 | * |
| 1292 | * We do not try to go to 1.5 times smaller bucket so far. |
| 1293 | */ |
| 1294 | if (nbytes > onb) incr = 1; |
| 1295 | else { |
| 1296 | #ifdef DO_NOT_TRY_HARDER_WHEN_SHRINKING |
| 1297 | if ( /* This is a little bit pessimal if PACK_MALLOC: */ |
| 1298 | nbytes > ( (onb >> 1) - M_OVERHEAD ) |
| 1299 | # ifdef TWO_POT_OPTIMIZE |
| 1300 | || (bucket == FIRST_BIG_POW2 && nbytes >= LAST_SMALL_BOUND ) |
| 1301 | # endif |
| 1302 | ) |
| 1303 | #else /* !DO_NOT_TRY_HARDER_WHEN_SHRINKING */ |
| 1304 | prev_bucket = ( (bucket > MAX_PACKED + 1) |
| 1305 | ? bucket - BUCKETS_PER_POW2 |
| 1306 | : bucket - 1); |
| 1307 | if (nbytes > BUCKET_SIZE_REAL(prev_bucket)) |
| 1308 | #endif /* !DO_NOT_TRY_HARDER_WHEN_SHRINKING */ |
| 1309 | incr = 0; |
| 1310 | else incr = -1; |
| 1311 | } |
| 1312 | if (!was_alloced |
| 1313 | #ifdef STRESS_REALLOC |
| 1314 | || 1 /* always do it the hard way */ |
| 1315 | #endif |
| 1316 | ) goto hard_way; |
| 1317 | else if (incr == 0) { |
| 1318 | inplace_label: |
| 1319 | #ifdef RCHECK |
| 1320 | /* |
| 1321 | * Record new allocated size of block and |
| 1322 | * bound space with magic numbers. |
| 1323 | */ |
| 1324 | if (OV_INDEX(ovp) <= MAX_SHORT_BUCKET) { |
| 1325 | int i, nb = ovp->ov_size + 1; |
| 1326 | |
| 1327 | if ((i = nb & 3)) { |
| 1328 | i = 4 - i; |
| 1329 | while (i--) { |
| 1330 | ASSERT(*((char *)((caddr_t)ovp + nb - RSLOP + i)) == RMAGIC_C, "chunk's tail overwrite"); |
| 1331 | } |
| 1332 | } |
| 1333 | nb = (nb + 3) &~ 3; |
| 1334 | ASSERT(*(u_int *)((caddr_t)ovp + nb - RSLOP) == RMAGIC, "chunk's tail overwrite"); |
| 1335 | /* |
| 1336 | * Convert amount of memory requested into |
| 1337 | * closest block size stored in hash buckets |
| 1338 | * which satisfies request. Account for |
| 1339 | * space used per block for accounting. |
| 1340 | */ |
| 1341 | nbytes += M_OVERHEAD; |
| 1342 | ovp->ov_size = nbytes - 1; |
| 1343 | if ((i = nbytes & 3)) { |
| 1344 | i = 4 - i; |
| 1345 | while (i--) |
| 1346 | *((char *)((caddr_t)ovp + nbytes - RSLOP + i)) |
| 1347 | = RMAGIC_C; |
| 1348 | } |
| 1349 | nbytes = (nbytes + 3) &~ 3; |
| 1350 | *((u_int *)((caddr_t)ovp + nbytes - RSLOP)) = RMAGIC; |
| 1351 | } |
| 1352 | #endif |
| 1353 | res = cp; |
| 1354 | MUTEX_UNLOCK(&malloc_mutex); |
| 1355 | } else if (incr == 1 && (cp - M_OVERHEAD == last_op) |
| 1356 | && (onb > (1 << LOG_OF_MIN_ARENA))) { |
| 1357 | MEM_SIZE require, newarena = nbytes, pow; |
| 1358 | int shiftr; |
| 1359 | |
| 1360 | POW2_OPTIMIZE_ADJUST(newarena); |
| 1361 | newarena = newarena + M_OVERHEAD; |
| 1362 | /* newarena = (newarena + 3) &~ 3; */ |
| 1363 | shiftr = (newarena - 1) >> LOG_OF_MIN_ARENA; |
| 1364 | pow = LOG_OF_MIN_ARENA + 1; |
| 1365 | /* apart from this loop, this is O(1) */ |
| 1366 | while (shiftr >>= 1) |
| 1367 | pow++; |
| 1368 | newarena = (1 << pow) + POW2_OPTIMIZE_SURPLUS(pow * BUCKETS_PER_POW2); |
| 1369 | require = newarena - onb - M_OVERHEAD; |
| 1370 | |
| 1371 | if (getpages_adjacent(require)) { |
| 1372 | #ifdef DEBUGGING_MSTATS |
| 1373 | nmalloc[bucket]--; |
| 1374 | nmalloc[pow * BUCKETS_PER_POW2]++; |
| 1375 | #endif |
| 1376 | *(cp - M_OVERHEAD) = pow * BUCKETS_PER_POW2; /* Fill index. */ |
| 1377 | goto inplace_label; |
| 1378 | } else |
| 1379 | goto hard_way; |
| 1380 | } else { |
| 1381 | hard_way: |
| 1382 | MUTEX_UNLOCK(&malloc_mutex); |
| 1383 | if ((res = (char*)malloc(nbytes)) == NULL) |
| 1384 | return (NULL); |
| 1385 | if (cp != res) /* common optimization */ |
| 1386 | Copy(cp, res, (MEM_SIZE)(nbytes<onb?nbytes:onb), char); |
| 1387 | if (was_alloced) |
| 1388 | free(cp); |
| 1389 | } |
| 1390 | |
| 1391 | DEBUG_m(PerlIO_printf(Perl_debug_log, "0x%lu: (%05lu) rfree\n", |
| 1392 | (unsigned long)res,(unsigned long)(an++))); |
| 1393 | DEBUG_m(PerlIO_printf(Perl_debug_log, |
| 1394 | "0x%lx: (%05lu) realloc %ld bytes\n", |
| 1395 | (unsigned long)res,(unsigned long)(an++), |
| 1396 | (long)size)); |
| 1397 | return ((Malloc_t)res); |
| 1398 | } |
| 1399 | |
| 1400 | /* |
| 1401 | * Search ``srchlen'' elements of each free list for a block whose |
| 1402 | * header starts at ``freep''. If srchlen is -1 search the whole list. |
| 1403 | * Return bucket number, or -1 if not found. |
| 1404 | */ |
| 1405 | static int |
| 1406 | findbucket(union overhead *freep, int srchlen) |
| 1407 | { |
| 1408 | register union overhead *p; |
| 1409 | register int i, j; |
| 1410 | |
| 1411 | for (i = 0; i < NBUCKETS; i++) { |
| 1412 | j = 0; |
| 1413 | for (p = nextf[i]; p && j != srchlen; p = p->ov_next) { |
| 1414 | if (p == freep) |
| 1415 | return (i); |
| 1416 | j++; |
| 1417 | } |
| 1418 | } |
| 1419 | return (-1); |
| 1420 | } |
| 1421 | |
| 1422 | Malloc_t |
| 1423 | calloc(register size_t elements, register size_t size) |
| 1424 | { |
| 1425 | long sz = elements * size; |
| 1426 | Malloc_t p = malloc(sz); |
| 1427 | |
| 1428 | if (p) { |
| 1429 | memset((void*)p, 0, sz); |
| 1430 | } |
| 1431 | return p; |
| 1432 | } |
| 1433 | |
| 1434 | MEM_SIZE |
| 1435 | malloced_size(void *p) |
| 1436 | { |
| 1437 | union overhead *ovp = (union overhead *) |
| 1438 | ((caddr_t)p - sizeof (union overhead) * CHUNK_SHIFT); |
| 1439 | int bucket = OV_INDEX(ovp); |
| 1440 | #ifdef RCHECK |
| 1441 | /* The caller wants to have a complete control over the chunk, |
| 1442 | disable the memory checking inside the chunk. */ |
| 1443 | if (bucket <= MAX_SHORT_BUCKET) { |
| 1444 | MEM_SIZE size = BUCKET_SIZE_REAL(bucket); |
| 1445 | ovp->ov_size = size + M_OVERHEAD - 1; |
| 1446 | *((u_int *)((caddr_t)ovp + size + M_OVERHEAD - RSLOP)) = RMAGIC; |
| 1447 | } |
| 1448 | #endif |
| 1449 | return BUCKET_SIZE_REAL(bucket); |
| 1450 | } |
| 1451 | |
| 1452 | #ifdef DEBUGGING_MSTATS |
| 1453 | |
| 1454 | # ifdef BUCKETS_ROOT2 |
| 1455 | # define MIN_EVEN_REPORT 6 |
| 1456 | # else |
| 1457 | # define MIN_EVEN_REPORT MIN_BUCKET |
| 1458 | # endif |
| 1459 | /* |
| 1460 | * mstats - print out statistics about malloc |
| 1461 | * |
| 1462 | * Prints two lines of numbers, one showing the length of the free list |
| 1463 | * for each size category, the second showing the number of mallocs - |
| 1464 | * frees for each size category. |
| 1465 | */ |
| 1466 | void |
| 1467 | dump_mstats(char *s) |
| 1468 | { |
| 1469 | register int i, j; |
| 1470 | register union overhead *p; |
| 1471 | int topbucket=0, topbucket_ev=0, topbucket_odd=0, totfree=0, total=0; |
| 1472 | u_int nfree[NBUCKETS]; |
| 1473 | int total_chain = 0; |
| 1474 | struct chunk_chain_s* nextchain = chunk_chain; |
| 1475 | |
| 1476 | for (i = MIN_BUCKET ; i < NBUCKETS; i++) { |
| 1477 | for (j = 0, p = nextf[i]; p; p = p->ov_next, j++) |
| 1478 | ; |
| 1479 | nfree[i] = j; |
| 1480 | totfree += nfree[i] * BUCKET_SIZE_REAL(i); |
| 1481 | total += nmalloc[i] * BUCKET_SIZE_REAL(i); |
| 1482 | if (nmalloc[i]) { |
| 1483 | i % 2 ? (topbucket_odd = i) : (topbucket_ev = i); |
| 1484 | topbucket = i; |
| 1485 | } |
| 1486 | } |
| 1487 | if (s) |
| 1488 | PerlIO_printf(PerlIO_stderr(), |
| 1489 | "Memory allocation statistics %s (buckets %ld(%ld)..%ld(%ld)\n", |
| 1490 | s, |
| 1491 | (long)BUCKET_SIZE_REAL(MIN_BUCKET), |
| 1492 | (long)BUCKET_SIZE(MIN_BUCKET), |
| 1493 | (long)BUCKET_SIZE_REAL(topbucket), (long)BUCKET_SIZE(topbucket)); |
| 1494 | PerlIO_printf(PerlIO_stderr(), "%8d free:", totfree); |
| 1495 | for (i = MIN_EVEN_REPORT; i <= topbucket; i += BUCKETS_PER_POW2) { |
| 1496 | PerlIO_printf(PerlIO_stderr(), |
| 1497 | ((i < 8*BUCKETS_PER_POW2 || i == 10*BUCKETS_PER_POW2) |
| 1498 | ? " %5d" |
| 1499 | : ((i < 12*BUCKETS_PER_POW2) ? " %3d" : " %d")), |
| 1500 | nfree[i]); |
| 1501 | } |
| 1502 | #ifdef BUCKETS_ROOT2 |
| 1503 | PerlIO_printf(PerlIO_stderr(), "\n\t "); |
| 1504 | for (i = MIN_BUCKET + 1; i <= topbucket_odd; i += BUCKETS_PER_POW2) { |
| 1505 | PerlIO_printf(PerlIO_stderr(), |
| 1506 | ((i < 8*BUCKETS_PER_POW2 || i == 10*BUCKETS_PER_POW2) |
| 1507 | ? " %5d" |
| 1508 | : ((i < 12*BUCKETS_PER_POW2) ? " %3d" : " %d")), |
| 1509 | nfree[i]); |
| 1510 | } |
| 1511 | #endif |
| 1512 | PerlIO_printf(PerlIO_stderr(), "\n%8d used:", total - totfree); |
| 1513 | for (i = MIN_EVEN_REPORT; i <= topbucket; i += BUCKETS_PER_POW2) { |
| 1514 | PerlIO_printf(PerlIO_stderr(), |
| 1515 | ((i < 8*BUCKETS_PER_POW2 || i == 10*BUCKETS_PER_POW2) |
| 1516 | ? " %5d" |
| 1517 | : ((i < 12*BUCKETS_PER_POW2) ? " %3d" : " %d")), |
| 1518 | nmalloc[i] - nfree[i]); |
| 1519 | } |
| 1520 | #ifdef BUCKETS_ROOT2 |
| 1521 | PerlIO_printf(PerlIO_stderr(), "\n\t "); |
| 1522 | for (i = MIN_BUCKET + 1; i <= topbucket_odd; i += BUCKETS_PER_POW2) { |
| 1523 | PerlIO_printf(PerlIO_stderr(), |
| 1524 | ((i < 8*BUCKETS_PER_POW2 || i == 10*BUCKETS_PER_POW2) |
| 1525 | ? " %5d" |
| 1526 | : ((i < 12*BUCKETS_PER_POW2) ? " %3d" : " %d")), |
| 1527 | nmalloc[i] - nfree[i]); |
| 1528 | } |
| 1529 | #endif |
| 1530 | while (nextchain) { |
| 1531 | total_chain += nextchain->size; |
| 1532 | nextchain = nextchain->next; |
| 1533 | } |
| 1534 | PerlIO_printf(PerlIO_stderr(), "\nTotal sbrk(): %d/%d:%d. Odd ends: pad+heads+chain+tail: %d+%d+%d+%d.\n", |
| 1535 | goodsbrk + sbrk_slack, sbrks, sbrk_good, sbrk_slack, |
| 1536 | start_slack, total_chain, sbrked_remains); |
| 1537 | } |
| 1538 | #else |
| 1539 | void |
| 1540 | dump_mstats(char *s) |
| 1541 | { |
| 1542 | } |
| 1543 | #endif |
| 1544 | #endif /* lint */ |
| 1545 | |
| 1546 | |
| 1547 | #ifdef USE_PERL_SBRK |
| 1548 | |
| 1549 | # ifdef NeXT |
| 1550 | # define PERL_SBRK_VIA_MALLOC |
| 1551 | # endif |
| 1552 | |
| 1553 | # ifdef __MACHTEN_PPC__ |
| 1554 | # define PERL_SBRK_VIA_MALLOC |
| 1555 | /* |
| 1556 | * MachTen's malloc() returns a buffer aligned on a two-byte boundary. |
| 1557 | * While this is adequate, it may slow down access to longer data |
| 1558 | * types by forcing multiple memory accesses. It also causes |
| 1559 | * complaints when RCHECK is in force. So we allocate six bytes |
| 1560 | * more than we need to, and return an address rounded up to an |
| 1561 | * eight-byte boundary. |
| 1562 | * |
| 1563 | * 980701 Dominic Dunlop <domo@computer.org> |
| 1564 | */ |
| 1565 | # define SYSTEM_ALLOC(a) ((void *)(((unsigned)malloc((a)+6)+6)&~7)) |
| 1566 | # endif |
| 1567 | |
| 1568 | # ifdef PERL_SBRK_VIA_MALLOC |
| 1569 | # if defined(HIDEMYMALLOC) || defined(EMBEDMYMALLOC) |
| 1570 | # undef malloc /* Expose names that */ |
| 1571 | # undef calloc /* HIDEMYMALLOC hides */ |
| 1572 | # undef realloc |
| 1573 | # undef free |
| 1574 | # else |
| 1575 | # include "Error: -DPERL_SBRK_VIA_MALLOC needs -D(HIDE|EMBED)MYMALLOC" |
| 1576 | # endif |
| 1577 | |
| 1578 | /* it may seem schizophrenic to use perl's malloc and let it call system */ |
| 1579 | /* malloc, the reason for that is only the 3.2 version of the OS that had */ |
| 1580 | /* frequent core dumps within nxzonefreenolock. This sbrk routine put an */ |
| 1581 | /* end to the cores */ |
| 1582 | |
| 1583 | # ifndef SYSTEM_ALLOC |
| 1584 | # define SYSTEM_ALLOC(a) malloc(a) |
| 1585 | # endif |
| 1586 | |
| 1587 | # endif /* PERL_SBRK_VIA_MALLOC */ |
| 1588 | |
| 1589 | static IV Perl_sbrk_oldchunk; |
| 1590 | static long Perl_sbrk_oldsize; |
| 1591 | |
| 1592 | # define PERLSBRK_32_K (1<<15) |
| 1593 | # define PERLSBRK_64_K (1<<16) |
| 1594 | |
| 1595 | Malloc_t |
| 1596 | Perl_sbrk(size) |
| 1597 | int size; |
| 1598 | { |
| 1599 | IV got; |
| 1600 | int small, reqsize; |
| 1601 | |
| 1602 | if (!size) return 0; |
| 1603 | #ifdef PERL_CORE |
| 1604 | reqsize = size; /* just for the DEBUG_m statement */ |
| 1605 | #endif |
| 1606 | #ifdef PACK_MALLOC |
| 1607 | size = (size + 0x7ff) & ~0x7ff; |
| 1608 | #endif |
| 1609 | if (size <= Perl_sbrk_oldsize) { |
| 1610 | got = Perl_sbrk_oldchunk; |
| 1611 | Perl_sbrk_oldchunk += size; |
| 1612 | Perl_sbrk_oldsize -= size; |
| 1613 | } else { |
| 1614 | if (size >= PERLSBRK_32_K) { |
| 1615 | small = 0; |
| 1616 | } else { |
| 1617 | size = PERLSBRK_64_K; |
| 1618 | small = 1; |
| 1619 | } |
| 1620 | got = (IV)SYSTEM_ALLOC(size); |
| 1621 | #ifdef PACK_MALLOC |
| 1622 | got = (got + 0x7ff) & ~0x7ff; |
| 1623 | #endif |
| 1624 | if (small) { |
| 1625 | /* Chunk is small, register the rest for future allocs. */ |
| 1626 | Perl_sbrk_oldchunk = got + reqsize; |
| 1627 | Perl_sbrk_oldsize = size - reqsize; |
| 1628 | } |
| 1629 | } |
| 1630 | |
| 1631 | DEBUG_m(PerlIO_printf(Perl_debug_log, "sbrk malloc size %ld (reqsize %ld), left size %ld, give addr 0x%lx\n", |
| 1632 | size, reqsize, Perl_sbrk_oldsize, got)); |
| 1633 | |
| 1634 | return (void *)got; |
| 1635 | } |
| 1636 | |
| 1637 | #endif /* ! defined USE_PERL_SBRK */ |