Commit | Line | Data |
---|---|---|
a0d0e21e | 1 | /* malloc.c |
8d063cd8 | 2 | * |
8d063cd8 LW |
3 | */ |
4 | ||
3562ef9b IZ |
5 | #if defined(PERL_CORE) && !defined(DEBUGGING_MSTATS) |
6 | # define DEBUGGING_MSTATS | |
7 | #endif | |
8 | ||
8d063cd8 | 9 | #ifndef lint |
1944739a IZ |
10 | # if defined(DEBUGGING) && !defined(NO_RCHECK) |
11 | # define RCHECK | |
12 | # endif | |
8d063cd8 LW |
13 | /* |
14 | * malloc.c (Caltech) 2/21/82 | |
15 | * Chris Kingsley, kingsley@cit-20. | |
16 | * | |
17 | * This is a very fast storage allocator. It allocates blocks of a small | |
18 | * number of different sizes, and keeps free lists of each size. Blocks that | |
19 | * don't exactly fit are passed up to the next larger size. In this | |
20 | * implementation, the available sizes are 2^n-4 (or 2^n-12) bytes long. | |
cf5c4ad8 | 21 | * If PACK_MALLOC is defined, small blocks are 2^n bytes long. |
8d063cd8 LW |
22 | * This is designed for use in a program that uses vast quantities of memory, |
23 | * but bombs when it runs out. | |
24 | */ | |
25 | ||
135863df | 26 | #include "EXTERN.h" |
135863df AB |
27 | #include "perl.h" |
28 | ||
760ac839 LW |
29 | #ifdef DEBUGGING |
30 | #undef DEBUG_m | |
31 | #define DEBUG_m(a) if (debug & 128) a | |
32 | #endif | |
33 | ||
135863df AB |
34 | /* I don't much care whether these are defined in sys/types.h--LAW */ |
35 | ||
36 | #define u_char unsigned char | |
37 | #define u_int unsigned int | |
38 | #define u_short unsigned short | |
8d063cd8 | 39 | |
cf5c4ad8 | 40 | /* 286 and atarist like big chunks, which gives too much overhead. */ |
41 | #if (defined(RCHECK) || defined(I286) || defined(atarist)) && defined(PACK_MALLOC) | |
42 | #undef PACK_MALLOC | |
43 | #endif | |
44 | ||
45 | ||
8d063cd8 | 46 | /* |
cf5c4ad8 | 47 | * The description below is applicable if PACK_MALLOC is not defined. |
48 | * | |
8d063cd8 LW |
49 | * The overhead on a block is at least 4 bytes. When free, this space |
50 | * contains a pointer to the next free block, and the bottom two bits must | |
51 | * be zero. When in use, the first byte is set to MAGIC, and the second | |
52 | * byte is the size index. The remaining bytes are for alignment. | |
53 | * If range checking is enabled and the size of the block fits | |
54 | * in two bytes, then the top two bytes hold the size of the requested block | |
55 | * plus the range checking words, and the header word MINUS ONE. | |
56 | */ | |
57 | union overhead { | |
58 | union overhead *ov_next; /* when free */ | |
85e6fe83 | 59 | #if MEM_ALIGNBYTES > 4 |
c623bd54 | 60 | double strut; /* alignment problems */ |
a687059c | 61 | #endif |
8d063cd8 LW |
62 | struct { |
63 | u_char ovu_magic; /* magic number */ | |
64 | u_char ovu_index; /* bucket # */ | |
65 | #ifdef RCHECK | |
66 | u_short ovu_size; /* actual block size */ | |
67 | u_int ovu_rmagic; /* range magic number */ | |
68 | #endif | |
69 | } ovu; | |
70 | #define ov_magic ovu.ovu_magic | |
71 | #define ov_index ovu.ovu_index | |
72 | #define ov_size ovu.ovu_size | |
73 | #define ov_rmagic ovu.ovu_rmagic | |
74 | }; | |
75 | ||
760ac839 | 76 | #ifdef DEBUGGING |
a0d0e21e LW |
77 | static void botch _((char *s)); |
78 | #endif | |
79 | static void morecore _((int bucket)); | |
80 | static int findbucket _((union overhead *freep, int srchlen)); | |
81 | ||
8d063cd8 LW |
82 | #define MAGIC 0xff /* magic # on accounting info */ |
83 | #define RMAGIC 0x55555555 /* magic # on range info */ | |
84 | #ifdef RCHECK | |
c2a5c2d2 IZ |
85 | # define RSLOP sizeof (u_int) |
86 | # ifdef TWO_POT_OPTIMIZE | |
87 | # define MAX_SHORT_BUCKET 12 | |
88 | # else | |
89 | # define MAX_SHORT_BUCKET 13 | |
90 | # endif | |
8d063cd8 | 91 | #else |
c2a5c2d2 | 92 | # define RSLOP 0 |
8d063cd8 LW |
93 | #endif |
94 | ||
cf5c4ad8 | 95 | #ifdef PACK_MALLOC |
96 | /* | |
97 | * In this case it is assumed that if we do sbrk() in 2K units, we | |
98 | * will get 2K aligned blocks. The bucket number of the given subblock is | |
99 | * on the boundary of 2K block which contains the subblock. | |
100 | * Several following bytes contain the magic numbers for the subblocks | |
101 | * in the block. | |
102 | * | |
103 | * Sizes of chunks are powers of 2 for chunks in buckets <= | |
104 | * MAX_PACKED, after this they are (2^n - sizeof(union overhead)) (to | |
105 | * get alignment right). | |
106 | * | |
107 | * We suppose that starts of all the chunks in a 2K block are in | |
108 | * different 2^n-byte-long chunks. If the top of the last chunk is | |
109 | * aligned on a boundary of 2K block, this means that | |
110 | * sizeof(union overhead)*"number of chunks" < 2^n, or | |
111 | * sizeof(union overhead)*2K < 4^n, or n > 6 + log2(sizeof()/2)/2, if a | |
112 | * chunk of size 2^n - overhead is used. Since this rules out n = 7 | |
113 | * for 8 byte alignment, we specialcase allocation of the first of 16 | |
114 | * 128-byte-long chunks. | |
115 | * | |
116 | * Note that with the above assumption we automatically have enough | |
117 | * place for MAGIC at the start of 2K block. Note also that we | |
118 | * overlay union overhead over the chunk, thus the start of the chunk | |
119 | * is immediately overwritten after freeing. | |
120 | */ | |
121 | # define MAX_PACKED 6 | |
122 | # define MAX_2_POT_ALGO ((1<<(MAX_PACKED + 1)) - M_OVERHEAD) | |
123 | # define TWOK_MASK ((1<<11) - 1) | |
ff68c719 | 124 | # define TWOK_MASKED(x) ((u_int)(x) & ~TWOK_MASK) |
125 | # define TWOK_SHIFT(x) ((u_int)(x) & TWOK_MASK) | |
cf5c4ad8 | 126 | # define OV_INDEXp(block) ((u_char*)(TWOK_MASKED(block))) |
127 | # define OV_INDEX(block) (*OV_INDEXp(block)) | |
128 | # define OV_MAGIC(block,bucket) (*(OV_INDEXp(block) + \ | |
129 | (TWOK_SHIFT(block)>>(bucket + 3)) + \ | |
130 | (bucket > MAX_NONSHIFT ? 1 : 0))) | |
131 | # define CHUNK_SHIFT 0 | |
132 | ||
133 | static u_char n_blks[11 - 3] = {224, 120, 62, 31, 16, 8, 4, 2}; | |
134 | static u_short blk_shift[11 - 3] = {256, 128, 64, 32, | |
135 | 16*sizeof(union overhead), | |
136 | 8*sizeof(union overhead), | |
137 | 4*sizeof(union overhead), | |
138 | 2*sizeof(union overhead), | |
139 | # define MAX_NONSHIFT 2 /* Shift 64 greater than chunk 32. */ | |
140 | }; | |
141 | ||
cf5c4ad8 | 142 | #else /* !PACK_MALLOC */ |
143 | ||
144 | # define OV_MAGIC(block,bucket) (block)->ov_magic | |
145 | # define OV_INDEX(block) (block)->ov_index | |
146 | # define CHUNK_SHIFT 1 | |
147 | #endif /* !PACK_MALLOC */ | |
148 | ||
149 | # define M_OVERHEAD (sizeof(union overhead) + RSLOP) | |
150 | ||
8d063cd8 | 151 | /* |
55497cff | 152 | * Big allocations are often of the size 2^n bytes. To make them a |
153 | * little bit better, make blocks of size 2^n+pagesize for big n. | |
154 | */ | |
155 | ||
156 | #ifdef TWO_POT_OPTIMIZE | |
157 | ||
5f05dabc | 158 | # ifndef PERL_PAGESIZE |
159 | # define PERL_PAGESIZE 4096 | |
160 | # endif | |
161 | # ifndef FIRST_BIG_TWO_POT | |
162 | # define FIRST_BIG_TWO_POT 14 /* 16K */ | |
163 | # endif | |
55497cff | 164 | # define FIRST_BIG_BLOCK (1<<FIRST_BIG_TWO_POT) /* 16K */ |
165 | /* If this value or more, check against bigger blocks. */ | |
166 | # define FIRST_BIG_BOUND (FIRST_BIG_BLOCK - M_OVERHEAD) | |
167 | /* If less than this value, goes into 2^n-overhead-block. */ | |
168 | # define LAST_SMALL_BOUND ((FIRST_BIG_BLOCK>>1) - M_OVERHEAD) | |
169 | ||
170 | #endif /* TWO_POT_OPTIMIZE */ | |
171 | ||
72e5b9db | 172 | #if defined(PERL_EMERGENCY_SBRK) && defined(PERL_CORE) |
55497cff | 173 | |
174 | #ifndef BIG_SIZE | |
175 | # define BIG_SIZE (1<<16) /* 64K */ | |
176 | #endif | |
177 | ||
178 | static char *emergency_buffer; | |
179 | static MEM_SIZE emergency_buffer_size; | |
180 | ||
181 | static char * | |
182 | emergency_sbrk(size) | |
183 | MEM_SIZE size; | |
184 | { | |
185 | if (size >= BIG_SIZE) { | |
186 | /* Give the possibility to recover: */ | |
187 | die("Out of memory during request for %i bytes", size); | |
188 | /* croak may eat too much memory. */ | |
189 | } | |
190 | ||
191 | if (!emergency_buffer) { | |
192 | /* First offense, give a possibility to recover by dieing. */ | |
193 | /* No malloc involved here: */ | |
194 | GV **gvp = (GV**)hv_fetch(defstash, "^M", 2, 0); | |
195 | SV *sv; | |
196 | char *pv; | |
197 | ||
198 | if (!gvp) gvp = (GV**)hv_fetch(defstash, "\015", 1, 0); | |
199 | if (!gvp || !(sv = GvSV(*gvp)) || !SvPOK(sv) | |
200 | || (SvLEN(sv) < (1<<11) - M_OVERHEAD)) | |
201 | return (char *)-1; /* Now die die die... */ | |
202 | ||
203 | /* Got it, now detach SvPV: */ | |
bbce6d69 | 204 | pv = SvPV(sv, na); |
55497cff | 205 | /* Check alignment: */ |
ff68c719 | 206 | if (((u_int)(pv - M_OVERHEAD)) & ((1<<11) - 1)) { |
55497cff | 207 | PerlIO_puts(PerlIO_stderr(),"Bad alignment of $^M!\n"); |
bbce6d69 | 208 | return (char *)-1; /* die die die */ |
55497cff | 209 | } |
210 | ||
211 | emergency_buffer = pv - M_OVERHEAD; | |
212 | emergency_buffer_size = SvLEN(sv) + M_OVERHEAD; | |
213 | SvPOK_off(sv); | |
214 | SvREADONLY_on(sv); | |
215 | die("Out of memory!"); /* croak may eat too much memory. */ | |
ff68c719 | 216 | } |
217 | else if (emergency_buffer_size >= size) { | |
55497cff | 218 | emergency_buffer_size -= size; |
219 | return emergency_buffer + emergency_buffer_size; | |
220 | } | |
221 | ||
222 | return (char *)-1; /* poor guy... */ | |
223 | } | |
224 | ||
72e5b9db | 225 | #else /* !(defined(TWO_POT_OPTIMIZE) && defined(PERL_CORE)) */ |
55497cff | 226 | # define emergency_sbrk(size) -1 |
72e5b9db | 227 | #endif /* !(defined(TWO_POT_OPTIMIZE) && defined(PERL_CORE)) */ |
55497cff | 228 | |
229 | /* | |
8d063cd8 LW |
230 | * nextf[i] is the pointer to the next free block of size 2^(i+3). The |
231 | * smallest allocatable block is 8 bytes. The overhead information | |
232 | * precedes the data area returned to the user. | |
233 | */ | |
234 | #define NBUCKETS 30 | |
235 | static union overhead *nextf[NBUCKETS]; | |
cf5c4ad8 | 236 | |
237 | #ifdef USE_PERL_SBRK | |
238 | #define sbrk(a) Perl_sbrk(a) | |
239 | char * Perl_sbrk _((int size)); | |
240 | #else | |
8d063cd8 | 241 | extern char *sbrk(); |
cf5c4ad8 | 242 | #endif |
8d063cd8 | 243 | |
c07a80fd | 244 | #ifdef DEBUGGING_MSTATS |
8d063cd8 LW |
245 | /* |
246 | * nmalloc[i] is the difference between the number of mallocs and frees | |
247 | * for a given block size. | |
248 | */ | |
249 | static u_int nmalloc[NBUCKETS]; | |
5f05dabc | 250 | static u_int goodsbrk; |
251 | static u_int sbrk_slack; | |
252 | static u_int start_slack; | |
8d063cd8 LW |
253 | #endif |
254 | ||
760ac839 | 255 | #ifdef DEBUGGING |
4dfc412b | 256 | #define ASSERT(p) if (!(p)) botch(STRINGIFY(p)); else |
ee0007ab | 257 | static void |
8d063cd8 LW |
258 | botch(s) |
259 | char *s; | |
260 | { | |
4dfc412b | 261 | PerlIO_printf(PerlIO_stderr(), "assertion botched: %s\n", s); |
8d063cd8 LW |
262 | abort(); |
263 | } | |
264 | #else | |
265 | #define ASSERT(p) | |
266 | #endif | |
267 | ||
2304df62 | 268 | Malloc_t |
8d063cd8 | 269 | malloc(nbytes) |
ee0007ab | 270 | register MEM_SIZE nbytes; |
8d063cd8 LW |
271 | { |
272 | register union overhead *p; | |
273 | register int bucket = 0; | |
ee0007ab | 274 | register MEM_SIZE shiftr; |
8d063cd8 | 275 | |
c2a5c2d2 | 276 | #if defined(DEBUGGING) || defined(RCHECK) |
ee0007ab | 277 | MEM_SIZE size = nbytes; |
45d8adaa LW |
278 | #endif |
279 | ||
043bf814 | 280 | #ifdef PERL_CORE |
55497cff | 281 | #ifdef HAS_64K_LIMIT |
45d8adaa | 282 | if (nbytes > 0xffff) { |
043bf814 RB |
283 | PerlIO_printf(PerlIO_stderr(), |
284 | "Allocation too large: %lx\n", (long)nbytes); | |
79072805 | 285 | my_exit(1); |
45d8adaa | 286 | } |
55497cff | 287 | #endif /* HAS_64K_LIMIT */ |
45d8adaa LW |
288 | #ifdef DEBUGGING |
289 | if ((long)nbytes < 0) | |
043bf814 | 290 | croak("panic: malloc"); |
45d8adaa | 291 | #endif |
55497cff | 292 | #endif /* PERL_CORE */ |
45d8adaa | 293 | |
11343788 | 294 | MUTEX_LOCK(&malloc_mutex); |
8d063cd8 LW |
295 | /* |
296 | * Convert amount of memory requested into | |
297 | * closest block size stored in hash buckets | |
298 | * which satisfies request. Account for | |
299 | * space used per block for accounting. | |
300 | */ | |
cf5c4ad8 | 301 | #ifdef PACK_MALLOC |
043bf814 RB |
302 | if (nbytes == 0) |
303 | nbytes = 1; | |
304 | else if (nbytes > MAX_2_POT_ALGO) | |
cf5c4ad8 | 305 | #endif |
043bf814 | 306 | { |
55497cff | 307 | #ifdef TWO_POT_OPTIMIZE |
043bf814 RB |
308 | if (nbytes >= FIRST_BIG_BOUND) |
309 | nbytes -= PERL_PAGESIZE; | |
55497cff | 310 | #endif |
043bf814 RB |
311 | nbytes += M_OVERHEAD; |
312 | nbytes = (nbytes + 3) &~ 3; | |
cf5c4ad8 | 313 | } |
8d063cd8 LW |
314 | shiftr = (nbytes - 1) >> 2; |
315 | /* apart from this loop, this is O(1) */ | |
316 | while (shiftr >>= 1) | |
317 | bucket++; | |
318 | /* | |
319 | * If nothing in hash bucket right now, | |
320 | * request more memory from the system. | |
321 | */ | |
322 | if (nextf[bucket] == NULL) | |
323 | morecore(bucket); | |
45d8adaa | 324 | if ((p = (union overhead *)nextf[bucket]) == NULL) { |
11343788 | 325 | MUTEX_UNLOCK(&malloc_mutex); |
55497cff | 326 | #ifdef PERL_CORE |
ee0007ab | 327 | if (!nomemok) { |
760ac839 | 328 | PerlIO_puts(PerlIO_stderr(),"Out of memory!\n"); |
79072805 | 329 | my_exit(1); |
ee0007ab | 330 | } |
45d8adaa | 331 | #else |
8d063cd8 | 332 | return (NULL); |
45d8adaa LW |
333 | #endif |
334 | } | |
335 | ||
55497cff | 336 | #ifdef PERL_CORE |
68dc0745 | 337 | DEBUG_m(PerlIO_printf(Perl_debug_log, "0x%lx: (%05lu) malloc %ld bytes\n", |
338 | (unsigned long)(p+1),(unsigned long)(an++),(long)size)); | |
55497cff | 339 | #endif /* PERL_CORE */ |
45d8adaa | 340 | |
8d063cd8 | 341 | /* remove from linked list */ |
bf38876a LW |
342 | #ifdef RCHECK |
343 | if (*((int*)p) & (sizeof(union overhead) - 1)) | |
760ac839 | 344 | PerlIO_printf(PerlIO_stderr(), "Corrupt malloc ptr 0x%lx at 0x%lx\n", |
a0d0e21e | 345 | (unsigned long)*((int*)p),(unsigned long)p); |
bf38876a LW |
346 | #endif |
347 | nextf[bucket] = p->ov_next; | |
cf5c4ad8 | 348 | OV_MAGIC(p, bucket) = MAGIC; |
349 | #ifndef PACK_MALLOC | |
350 | OV_INDEX(p) = bucket; | |
351 | #endif | |
8d063cd8 LW |
352 | #ifdef RCHECK |
353 | /* | |
354 | * Record allocated size of block and | |
355 | * bound space with magic numbers. | |
356 | */ | |
c2a5c2d2 | 357 | nbytes = (size + M_OVERHEAD + 3) &~ 3; |
8d063cd8 LW |
358 | if (nbytes <= 0x10000) |
359 | p->ov_size = nbytes - 1; | |
360 | p->ov_rmagic = RMAGIC; | |
361 | *((u_int *)((caddr_t)p + nbytes - RSLOP)) = RMAGIC; | |
362 | #endif | |
11343788 | 363 | MUTEX_UNLOCK(&malloc_mutex); |
cf5c4ad8 | 364 | return ((Malloc_t)(p + CHUNK_SHIFT)); |
8d063cd8 LW |
365 | } |
366 | ||
367 | /* | |
368 | * Allocate more memory to the indicated bucket. | |
369 | */ | |
a0d0e21e | 370 | static void |
8d063cd8 | 371 | morecore(bucket) |
a687059c | 372 | register int bucket; |
8d063cd8 | 373 | { |
72aaf631 | 374 | register union overhead *ovp; |
8d063cd8 LW |
375 | register int rnu; /* 2^rnu bytes will be requested */ |
376 | register int nblks; /* become nblks blocks of the desired size */ | |
bbce6d69 | 377 | register MEM_SIZE siz, needed; |
cf5c4ad8 | 378 | int slack = 0; |
8d063cd8 LW |
379 | |
380 | if (nextf[bucket]) | |
381 | return; | |
55497cff | 382 | if (bucket == (sizeof(MEM_SIZE)*8 - 3)) { |
383 | croak("Allocation too large"); | |
384 | } | |
8d063cd8 LW |
385 | /* |
386 | * Insure memory is allocated | |
387 | * on a page boundary. Should | |
388 | * make getpageize call? | |
389 | */ | |
ee0007ab | 390 | #ifndef atarist /* on the atari we dont have to worry about this */ |
72aaf631 | 391 | ovp = (union overhead *)sbrk(0); |
cf5c4ad8 | 392 | # ifndef I286 |
72aaf631 MB |
393 | if ((UV)ovp & (0x7FF >> CHUNK_SHIFT)) { |
394 | slack = (0x800 >> CHUNK_SHIFT) - ((UV)ovp & (0x7FF >> CHUNK_SHIFT)); | |
c030ccd9 | 395 | (void)sbrk(slack); |
5f05dabc | 396 | # if defined(DEBUGGING_MSTATS) |
c030ccd9 | 397 | sbrk_slack += slack; |
cf5c4ad8 | 398 | # endif |
c030ccd9 | 399 | } |
cf5c4ad8 | 400 | # else |
a687059c | 401 | /* The sbrk(0) call on the I286 always returns the next segment */ |
cf5c4ad8 | 402 | # endif |
ee0007ab | 403 | #endif /* atarist */ |
a687059c | 404 | |
ee0007ab | 405 | #if !(defined(I286) || defined(atarist)) |
8d063cd8 LW |
406 | /* take 2k unless the block is bigger than that */ |
407 | rnu = (bucket <= 8) ? 11 : bucket + 3; | |
a687059c LW |
408 | #else |
409 | /* take 16k unless the block is bigger than that | |
ee0007ab | 410 | (80286s like large segments!), probably good on the atari too */ |
a687059c LW |
411 | rnu = (bucket <= 11) ? 14 : bucket + 3; |
412 | #endif | |
8d063cd8 | 413 | nblks = 1 << (rnu - (bucket + 3)); /* how many blocks to get */ |
bbce6d69 | 414 | needed = (MEM_SIZE)1 << rnu; |
55497cff | 415 | #ifdef TWO_POT_OPTIMIZE |
bbce6d69 | 416 | needed += (bucket >= (FIRST_BIG_TWO_POT - 3) ? PERL_PAGESIZE : 0); |
55497cff | 417 | #endif |
72aaf631 | 418 | ovp = (union overhead *)sbrk(needed); |
8d063cd8 | 419 | /* no more room! */ |
72aaf631 MB |
420 | if (ovp == (union overhead *)-1) { |
421 | ovp = (union overhead *)emergency_sbrk(needed); | |
422 | if (ovp == (union overhead *)-1) | |
8d063cd8 | 423 | return; |
ff68c719 | 424 | } |
5f05dabc | 425 | #ifdef DEBUGGING_MSTATS |
426 | goodsbrk += needed; | |
427 | #endif | |
8d063cd8 LW |
428 | /* |
429 | * Round up to minimum allocation size boundary | |
430 | * and deduct from block count to reflect. | |
431 | */ | |
a687059c | 432 | #ifndef I286 |
cf5c4ad8 | 433 | # ifdef PACK_MALLOC |
72aaf631 | 434 | if ((UV)ovp & 0x7FF) |
cf5c4ad8 | 435 | croak("panic: Off-page sbrk"); |
436 | # endif | |
72aaf631 MB |
437 | if ((UV)ovp & 7) { |
438 | ovp = (union overhead *)(((UV)ovp + 8) & ~7); | |
8d063cd8 LW |
439 | nblks--; |
440 | } | |
a687059c LW |
441 | #else |
442 | /* Again, this should always be ok on an 80286 */ | |
443 | #endif | |
8d063cd8 LW |
444 | /* |
445 | * Add new memory allocated to that on | |
446 | * free list for this hash bucket. | |
447 | */ | |
8d063cd8 | 448 | siz = 1 << (bucket + 3); |
cf5c4ad8 | 449 | #ifdef PACK_MALLOC |
72aaf631 | 450 | *(u_char*)ovp = bucket; /* Fill index. */ |
cf5c4ad8 | 451 | if (bucket <= MAX_PACKED - 3) { |
72aaf631 | 452 | ovp = (union overhead *) ((char*)ovp + blk_shift[bucket]); |
cf5c4ad8 | 453 | nblks = n_blks[bucket]; |
454 | # ifdef DEBUGGING_MSTATS | |
455 | start_slack += blk_shift[bucket]; | |
456 | # endif | |
457 | } else if (bucket <= 11 - 1 - 3) { | |
72aaf631 | 458 | ovp = (union overhead *) ((char*)ovp + blk_shift[bucket]); |
cf5c4ad8 | 459 | /* nblks = n_blks[bucket]; */ |
460 | siz -= sizeof(union overhead); | |
72aaf631 | 461 | } else ovp++; /* One chunk per block. */ |
cf5c4ad8 | 462 | #endif /* !PACK_MALLOC */ |
72aaf631 | 463 | nextf[bucket] = ovp; |
5f05dabc | 464 | #ifdef DEBUGGING_MSTATS |
465 | nmalloc[bucket] += nblks; | |
466 | #endif | |
8d063cd8 | 467 | while (--nblks > 0) { |
72aaf631 MB |
468 | ovp->ov_next = (union overhead *)((caddr_t)ovp + siz); |
469 | ovp = (union overhead *)((caddr_t)ovp + siz); | |
8d063cd8 | 470 | } |
8595d6f1 | 471 | /* Not all sbrks return zeroed memory.*/ |
72aaf631 | 472 | ovp->ov_next = (union overhead *)NULL; |
cf5c4ad8 | 473 | #ifdef PACK_MALLOC |
474 | if (bucket == 7 - 3) { /* Special case, explanation is above. */ | |
475 | union overhead *n_op = nextf[7 - 3]->ov_next; | |
476 | nextf[7 - 3] = (union overhead *)((caddr_t)nextf[7 - 3] | |
477 | - sizeof(union overhead)); | |
478 | nextf[7 - 3]->ov_next = n_op; | |
479 | } | |
480 | #endif /* !PACK_MALLOC */ | |
8d063cd8 LW |
481 | } |
482 | ||
94b6baf5 | 483 | Free_t |
352d5a3a | 484 | free(mp) |
2304df62 | 485 | Malloc_t mp; |
8d063cd8 | 486 | { |
ee0007ab | 487 | register MEM_SIZE size; |
72aaf631 | 488 | register union overhead *ovp; |
352d5a3a | 489 | char *cp = (char*)mp; |
cf5c4ad8 | 490 | #ifdef PACK_MALLOC |
491 | u_char bucket; | |
492 | #endif | |
8d063cd8 | 493 | |
55497cff | 494 | #ifdef PERL_CORE |
68dc0745 | 495 | DEBUG_m(PerlIO_printf(Perl_debug_log, "0x%lx: (%05lu) free\n",(unsigned long)cp,(unsigned long)(an++))); |
55497cff | 496 | #endif /* PERL_CORE */ |
45d8adaa | 497 | |
cf5c4ad8 | 498 | if (cp == NULL) |
499 | return; | |
72aaf631 MB |
500 | ovp = (union overhead *)((caddr_t)cp |
501 | - sizeof (union overhead) * CHUNK_SHIFT); | |
cf5c4ad8 | 502 | #ifdef PACK_MALLOC |
72aaf631 | 503 | bucket = OV_INDEX(ovp); |
cf5c4ad8 | 504 | #endif |
72aaf631 | 505 | if (OV_MAGIC(ovp, bucket) != MAGIC) { |
68dc0745 | 506 | static int bad_free_warn = -1; |
cf5c4ad8 | 507 | if (bad_free_warn == -1) { |
508 | char *pbf = getenv("PERL_BADFREE"); | |
509 | bad_free_warn = (pbf) ? atoi(pbf) : 1; | |
510 | } | |
511 | if (!bad_free_warn) | |
512 | return; | |
8990e307 | 513 | #ifdef RCHECK |
a687059c | 514 | warn("%s free() ignored", |
72aaf631 | 515 | ovp->ov_rmagic == RMAGIC - 1 ? "Duplicate" : "Bad"); |
8990e307 LW |
516 | #else |
517 | warn("Bad free() ignored"); | |
518 | #endif | |
8d063cd8 | 519 | return; /* sanity */ |
378cc40b | 520 | } |
11343788 | 521 | MUTEX_LOCK(&malloc_mutex); |
8d063cd8 | 522 | #ifdef RCHECK |
72aaf631 MB |
523 | ASSERT(ovp->ov_rmagic == RMAGIC); |
524 | if (OV_INDEX(ovp) <= MAX_SHORT_BUCKET) | |
525 | ASSERT(*(u_int *)((caddr_t)ovp + ovp->ov_size + 1 - RSLOP) == RMAGIC); | |
526 | ovp->ov_rmagic = RMAGIC - 1; | |
8d063cd8 | 527 | #endif |
72aaf631 MB |
528 | ASSERT(OV_INDEX(ovp) < NBUCKETS); |
529 | size = OV_INDEX(ovp); | |
530 | ovp->ov_next = nextf[size]; | |
531 | nextf[size] = ovp; | |
11343788 | 532 | MUTEX_UNLOCK(&malloc_mutex); |
8d063cd8 LW |
533 | } |
534 | ||
535 | /* | |
536 | * When a program attempts "storage compaction" as mentioned in the | |
537 | * old malloc man page, it realloc's an already freed block. Usually | |
538 | * this is the last block it freed; occasionally it might be farther | |
539 | * back. We have to search all the free lists for the block in order | |
540 | * to determine its bucket: 1st we make one pass thru the lists | |
541 | * checking only the first block in each; if that fails we search | |
378cc40b | 542 | * ``reall_srchlen'' blocks in each list for a match (the variable |
8d063cd8 LW |
543 | * is extern so the caller can modify it). If that fails we just copy |
544 | * however many bytes was given to realloc() and hope it's not huge. | |
545 | */ | |
378cc40b | 546 | int reall_srchlen = 4; /* 4 should be plenty, -1 =>'s whole list */ |
8d063cd8 | 547 | |
2304df62 | 548 | Malloc_t |
352d5a3a | 549 | realloc(mp, nbytes) |
2304df62 | 550 | Malloc_t mp; |
ee0007ab | 551 | MEM_SIZE nbytes; |
8d063cd8 | 552 | { |
ee0007ab | 553 | register MEM_SIZE onb; |
72aaf631 | 554 | union overhead *ovp; |
8d063cd8 LW |
555 | char *res; |
556 | register int i; | |
557 | int was_alloced = 0; | |
352d5a3a | 558 | char *cp = (char*)mp; |
8d063cd8 | 559 | |
45d8adaa | 560 | #ifdef DEBUGGING |
ee0007ab | 561 | MEM_SIZE size = nbytes; |
45d8adaa LW |
562 | #endif |
563 | ||
043bf814 | 564 | #ifdef PERL_CORE |
55497cff | 565 | #ifdef HAS_64K_LIMIT |
45d8adaa | 566 | if (nbytes > 0xffff) { |
043bf814 RB |
567 | PerlIO_printf(PerlIO_stderr(), |
568 | "Reallocation too large: %lx\n", size); | |
79072805 | 569 | my_exit(1); |
45d8adaa | 570 | } |
55497cff | 571 | #endif /* HAS_64K_LIMIT */ |
45d8adaa | 572 | if (!cp) |
ee0007ab | 573 | return malloc(nbytes); |
45d8adaa LW |
574 | #ifdef DEBUGGING |
575 | if ((long)nbytes < 0) | |
463ee0b2 | 576 | croak("panic: realloc"); |
45d8adaa | 577 | #endif |
55497cff | 578 | #endif /* PERL_CORE */ |
45d8adaa | 579 | |
11343788 | 580 | MUTEX_LOCK(&malloc_mutex); |
72aaf631 MB |
581 | ovp = (union overhead *)((caddr_t)cp |
582 | - sizeof (union overhead) * CHUNK_SHIFT); | |
583 | i = OV_INDEX(ovp); | |
584 | if (OV_MAGIC(ovp, i) == MAGIC) { | |
55497cff | 585 | was_alloced = 1; |
8d063cd8 LW |
586 | } else { |
587 | /* | |
588 | * Already free, doing "compaction". | |
589 | * | |
590 | * Search for the old block of memory on the | |
591 | * free list. First, check the most common | |
592 | * case (last element free'd), then (this failing) | |
378cc40b | 593 | * the last ``reall_srchlen'' items free'd. |
8d063cd8 LW |
594 | * If all lookups fail, then assume the size of |
595 | * the memory block being realloc'd is the | |
596 | * smallest possible. | |
597 | */ | |
72aaf631 MB |
598 | if ((i = findbucket(ovp, 1)) < 0 && |
599 | (i = findbucket(ovp, reall_srchlen)) < 0) | |
8d063cd8 LW |
600 | i = 0; |
601 | } | |
cf5c4ad8 | 602 | onb = (1L << (i + 3)) - |
603 | #ifdef PACK_MALLOC | |
604 | (i <= (MAX_PACKED - 3) ? 0 : M_OVERHEAD) | |
605 | #else | |
606 | M_OVERHEAD | |
607 | #endif | |
55497cff | 608 | #ifdef TWO_POT_OPTIMIZE |
609 | + (i >= (FIRST_BIG_TWO_POT - 3) ? PERL_PAGESIZE : 0) | |
610 | #endif | |
cf5c4ad8 | 611 | ; |
55497cff | 612 | /* |
613 | * avoid the copy if same size block. | |
614 | * We are not agressive with boundary cases. Note that it is | |
615 | * possible for small number of cases give false negative if | |
616 | * both new size and old one are in the bucket for | |
617 | * FIRST_BIG_TWO_POT, but the new one is near the lower end. | |
618 | */ | |
8d063cd8 | 619 | if (was_alloced && |
55497cff | 620 | nbytes <= onb && (nbytes > ( (onb >> 1) - M_OVERHEAD ) |
621 | #ifdef TWO_POT_OPTIMIZE | |
622 | || (i == (FIRST_BIG_TWO_POT - 3) | |
623 | && nbytes >= LAST_SMALL_BOUND ) | |
624 | #endif | |
625 | )) { | |
a687059c LW |
626 | #ifdef RCHECK |
627 | /* | |
628 | * Record new allocated size of block and | |
629 | * bound space with magic numbers. | |
630 | */ | |
72aaf631 | 631 | if (OV_INDEX(ovp) <= MAX_SHORT_BUCKET) { |
a687059c LW |
632 | /* |
633 | * Convert amount of memory requested into | |
634 | * closest block size stored in hash buckets | |
635 | * which satisfies request. Account for | |
636 | * space used per block for accounting. | |
637 | */ | |
cf5c4ad8 | 638 | nbytes += M_OVERHEAD; |
a687059c | 639 | nbytes = (nbytes + 3) &~ 3; |
72aaf631 MB |
640 | ovp->ov_size = nbytes - 1; |
641 | *((u_int *)((caddr_t)ovp + nbytes - RSLOP)) = RMAGIC; | |
a687059c LW |
642 | } |
643 | #endif | |
45d8adaa | 644 | res = cp; |
11343788 | 645 | MUTEX_UNLOCK(&malloc_mutex); |
a687059c | 646 | } |
45d8adaa | 647 | else { |
11343788 | 648 | MUTEX_UNLOCK(&malloc_mutex); |
45d8adaa LW |
649 | if ((res = (char*)malloc(nbytes)) == NULL) |
650 | return (NULL); | |
651 | if (cp != res) /* common optimization */ | |
ee0007ab | 652 | Copy(cp, res, (MEM_SIZE)(nbytes<onb?nbytes:onb), char); |
45d8adaa LW |
653 | if (was_alloced) |
654 | free(cp); | |
655 | } | |
656 | ||
55497cff | 657 | #ifdef PERL_CORE |
45d8adaa | 658 | #ifdef DEBUGGING |
a0d0e21e | 659 | if (debug & 128) { |
fb73857a | 660 | PerlIO_printf(Perl_debug_log, "0x%lx: (%05lu) rfree\n",(unsigned long)res,(unsigned long)(an++)); |
661 | PerlIO_printf(Perl_debug_log, "0x%lx: (%05lu) realloc %ld bytes\n", | |
68dc0745 | 662 | (unsigned long)res,(unsigned long)(an++),(long)size); |
a0d0e21e | 663 | } |
45d8adaa | 664 | #endif |
55497cff | 665 | #endif /* PERL_CORE */ |
2304df62 | 666 | return ((Malloc_t)res); |
8d063cd8 LW |
667 | } |
668 | ||
669 | /* | |
670 | * Search ``srchlen'' elements of each free list for a block whose | |
671 | * header starts at ``freep''. If srchlen is -1 search the whole list. | |
672 | * Return bucket number, or -1 if not found. | |
673 | */ | |
ee0007ab | 674 | static int |
8d063cd8 LW |
675 | findbucket(freep, srchlen) |
676 | union overhead *freep; | |
677 | int srchlen; | |
678 | { | |
679 | register union overhead *p; | |
680 | register int i, j; | |
681 | ||
682 | for (i = 0; i < NBUCKETS; i++) { | |
683 | j = 0; | |
684 | for (p = nextf[i]; p && j != srchlen; p = p->ov_next) { | |
685 | if (p == freep) | |
686 | return (i); | |
687 | j++; | |
688 | } | |
689 | } | |
690 | return (-1); | |
691 | } | |
692 | ||
cf5c4ad8 | 693 | Malloc_t |
694 | calloc(elements, size) | |
695 | register MEM_SIZE elements; | |
696 | register MEM_SIZE size; | |
697 | { | |
698 | long sz = elements * size; | |
699 | Malloc_t p = malloc(sz); | |
700 | ||
701 | if (p) { | |
702 | memset((void*)p, 0, sz); | |
703 | } | |
704 | return p; | |
705 | } | |
706 | ||
c07a80fd | 707 | #ifdef DEBUGGING_MSTATS |
8d063cd8 LW |
708 | /* |
709 | * mstats - print out statistics about malloc | |
710 | * | |
711 | * Prints two lines of numbers, one showing the length of the free list | |
712 | * for each size category, the second showing the number of mallocs - | |
713 | * frees for each size category. | |
714 | */ | |
ee0007ab | 715 | void |
c07a80fd | 716 | dump_mstats(s) |
8d063cd8 LW |
717 | char *s; |
718 | { | |
719 | register int i, j; | |
720 | register union overhead *p; | |
5f05dabc | 721 | int topbucket=0, totfree=0, total=0; |
c07a80fd | 722 | u_int nfree[NBUCKETS]; |
8d063cd8 | 723 | |
c07a80fd | 724 | for (i=0; i < NBUCKETS; i++) { |
8d063cd8 LW |
725 | for (j = 0, p = nextf[i]; p; p = p->ov_next, j++) |
726 | ; | |
c07a80fd | 727 | nfree[i] = j; |
728 | totfree += nfree[i] * (1 << (i + 3)); | |
5f05dabc | 729 | total += nmalloc[i] * (1 << (i + 3)); |
730 | if (nmalloc[i]) | |
c07a80fd | 731 | topbucket = i; |
732 | } | |
733 | if (s) | |
760ac839 | 734 | PerlIO_printf(PerlIO_stderr(), "Memory allocation statistics %s (buckets 8..%d)\n", |
c07a80fd | 735 | s, (1 << (topbucket + 3)) ); |
5f05dabc | 736 | PerlIO_printf(PerlIO_stderr(), "%8d free:", totfree); |
c07a80fd | 737 | for (i=0; i <= topbucket; i++) { |
5f05dabc | 738 | PerlIO_printf(PerlIO_stderr(), (i<5 || i==7)?" %5d": (i<9)?" %3d":" %d", nfree[i]); |
8d063cd8 | 739 | } |
5f05dabc | 740 | PerlIO_printf(PerlIO_stderr(), "\n%8d used:", total - totfree); |
c07a80fd | 741 | for (i=0; i <= topbucket; i++) { |
5f05dabc | 742 | PerlIO_printf(PerlIO_stderr(), (i<5 || i==7)?" %5d": (i<9)?" %3d":" %d", nmalloc[i] - nfree[i]); |
c07a80fd | 743 | } |
5f05dabc | 744 | PerlIO_printf(PerlIO_stderr(), "\nTotal sbrk(): %8d. Odd ends: sbrk(): %7d, malloc(): %7d bytes.\n", |
745 | goodsbrk + sbrk_slack, sbrk_slack, start_slack); | |
c07a80fd | 746 | } |
747 | #else | |
748 | void | |
749 | dump_mstats(s) | |
750 | char *s; | |
751 | { | |
8d063cd8 LW |
752 | } |
753 | #endif | |
a687059c | 754 | #endif /* lint */ |
cf5c4ad8 | 755 | |
756 | ||
757 | #ifdef USE_PERL_SBRK | |
758 | ||
760ac839 LW |
759 | # ifdef NeXT |
760 | # define PERL_SBRK_VIA_MALLOC | |
761 | # endif | |
762 | ||
763 | # ifdef PERL_SBRK_VIA_MALLOC | |
72e5b9db | 764 | # if defined(HIDEMYMALLOC) || defined(EMBEDMYMALLOC) |
760ac839 LW |
765 | # undef malloc |
766 | # else | |
72e5b9db | 767 | # include "Error: -DPERL_SBRK_VIA_MALLOC needs -D(HIDE|EMBED)MYMALLOC" |
760ac839 | 768 | # endif |
cf5c4ad8 | 769 | |
770 | /* it may seem schizophrenic to use perl's malloc and let it call system */ | |
771 | /* malloc, the reason for that is only the 3.2 version of the OS that had */ | |
772 | /* frequent core dumps within nxzonefreenolock. This sbrk routine put an */ | |
773 | /* end to the cores */ | |
774 | ||
760ac839 | 775 | # define SYSTEM_ALLOC(a) malloc(a) |
cf5c4ad8 | 776 | |
760ac839 | 777 | # endif /* PERL_SBRK_VIA_MALLOC */ |
cf5c4ad8 | 778 | |
779 | static IV Perl_sbrk_oldchunk; | |
780 | static long Perl_sbrk_oldsize; | |
781 | ||
760ac839 LW |
782 | # define PERLSBRK_32_K (1<<15) |
783 | # define PERLSBRK_64_K (1<<16) | |
cf5c4ad8 | 784 | |
785 | char * | |
786 | Perl_sbrk(size) | |
787 | int size; | |
788 | { | |
789 | IV got; | |
790 | int small, reqsize; | |
791 | ||
792 | if (!size) return 0; | |
55497cff | 793 | #ifdef PERL_CORE |
cf5c4ad8 | 794 | reqsize = size; /* just for the DEBUG_m statement */ |
795 | #endif | |
57569e04 HM |
796 | #ifdef PACK_MALLOC |
797 | size = (size + 0x7ff) & ~0x7ff; | |
798 | #endif | |
cf5c4ad8 | 799 | if (size <= Perl_sbrk_oldsize) { |
800 | got = Perl_sbrk_oldchunk; | |
801 | Perl_sbrk_oldchunk += size; | |
802 | Perl_sbrk_oldsize -= size; | |
803 | } else { | |
804 | if (size >= PERLSBRK_32_K) { | |
805 | small = 0; | |
806 | } else { | |
55497cff | 807 | #ifndef PERL_CORE |
cf5c4ad8 | 808 | reqsize = size; |
809 | #endif | |
810 | size = PERLSBRK_64_K; | |
811 | small = 1; | |
812 | } | |
813 | got = (IV)SYSTEM_ALLOC(size); | |
57569e04 HM |
814 | #ifdef PACK_MALLOC |
815 | got = (got + 0x7ff) & ~0x7ff; | |
816 | #endif | |
cf5c4ad8 | 817 | if (small) { |
818 | /* Chunk is small, register the rest for future allocs. */ | |
819 | Perl_sbrk_oldchunk = got + reqsize; | |
820 | Perl_sbrk_oldsize = size - reqsize; | |
821 | } | |
822 | } | |
823 | ||
55497cff | 824 | #ifdef PERL_CORE |
fb73857a | 825 | DEBUG_m(PerlIO_printf(Perl_debug_log, "sbrk malloc size %ld (reqsize %ld), left size %ld, give addr 0x%lx\n", |
cf5c4ad8 | 826 | size, reqsize, Perl_sbrk_oldsize, got)); |
827 | #endif | |
828 | ||
829 | return (void *)got; | |
830 | } | |
831 | ||
832 | #endif /* ! defined USE_PERL_SBRK */ |