Commit | Line | Data |
a0d0e21e |
1 | /* malloc.c |
8d063cd8 |
2 | * |
8d063cd8 |
3 | */ |
4 | |
f7542a9d |
5 | #define EMBEDMYMALLOC |
6 | |
3562ef9b |
7 | #if defined(PERL_CORE) && !defined(DEBUGGING_MSTATS) |
8 | # define DEBUGGING_MSTATS |
9 | #endif |
10 | |
8d063cd8 |
11 | #ifndef lint |
1944739a |
12 | # if defined(DEBUGGING) && !defined(NO_RCHECK) |
13 | # define RCHECK |
14 | # endif |
8d063cd8 |
15 | /* |
16 | * malloc.c (Caltech) 2/21/82 |
17 | * Chris Kingsley, kingsley@cit-20. |
18 | * |
19 | * This is a very fast storage allocator. It allocates blocks of a small |
20 | * number of different sizes, and keeps free lists of each size. Blocks that |
21 | * don't exactly fit are passed up to the next larger size. In this |
22 | * implementation, the available sizes are 2^n-4 (or 2^n-12) bytes long. |
cf5c4ad8 |
23 | * If PACK_MALLOC is defined, small blocks are 2^n bytes long. |
8d063cd8 |
24 | * This is designed for use in a program that uses vast quantities of memory, |
25 | * but bombs when it runs out. |
26 | */ |
27 | |
135863df |
28 | #include "EXTERN.h" |
135863df |
29 | #include "perl.h" |
30 | |
760ac839 |
31 | #ifdef DEBUGGING |
32 | #undef DEBUG_m |
33 | #define DEBUG_m(a) if (debug & 128) a |
34 | #endif |
35 | |
135863df |
36 | /* I don't much care whether these are defined in sys/types.h--LAW */ |
37 | |
38 | #define u_char unsigned char |
39 | #define u_int unsigned int |
40 | #define u_short unsigned short |
8d063cd8 |
41 | |
cf5c4ad8 |
42 | /* 286 and atarist like big chunks, which gives too much overhead. */ |
43 | #if (defined(RCHECK) || defined(I286) || defined(atarist)) && defined(PACK_MALLOC) |
44 | #undef PACK_MALLOC |
45 | #endif |
46 | |
47 | |
8d063cd8 |
48 | /* |
cf5c4ad8 |
49 | * The description below is applicable if PACK_MALLOC is not defined. |
50 | * |
8d063cd8 |
51 | * The overhead on a block is at least 4 bytes. When free, this space |
52 | * contains a pointer to the next free block, and the bottom two bits must |
53 | * be zero. When in use, the first byte is set to MAGIC, and the second |
54 | * byte is the size index. The remaining bytes are for alignment. |
55 | * If range checking is enabled and the size of the block fits |
56 | * in two bytes, then the top two bytes hold the size of the requested block |
57 | * plus the range checking words, and the header word MINUS ONE. |
58 | */ |
59 | union overhead { |
60 | union overhead *ov_next; /* when free */ |
85e6fe83 |
61 | #if MEM_ALIGNBYTES > 4 |
c623bd54 |
62 | double strut; /* alignment problems */ |
a687059c |
63 | #endif |
8d063cd8 |
64 | struct { |
65 | u_char ovu_magic; /* magic number */ |
66 | u_char ovu_index; /* bucket # */ |
67 | #ifdef RCHECK |
68 | u_short ovu_size; /* actual block size */ |
69 | u_int ovu_rmagic; /* range magic number */ |
70 | #endif |
71 | } ovu; |
72 | #define ov_magic ovu.ovu_magic |
73 | #define ov_index ovu.ovu_index |
74 | #define ov_size ovu.ovu_size |
75 | #define ov_rmagic ovu.ovu_rmagic |
76 | }; |
77 | |
760ac839 |
78 | #ifdef DEBUGGING |
a0d0e21e |
79 | static void botch _((char *s)); |
80 | #endif |
81 | static void morecore _((int bucket)); |
82 | static int findbucket _((union overhead *freep, int srchlen)); |
83 | |
8d063cd8 |
84 | #define MAGIC 0xff /* magic # on accounting info */ |
85 | #define RMAGIC 0x55555555 /* magic # on range info */ |
86 | #ifdef RCHECK |
c2a5c2d2 |
87 | # define RSLOP sizeof (u_int) |
88 | # ifdef TWO_POT_OPTIMIZE |
89 | # define MAX_SHORT_BUCKET 12 |
90 | # else |
91 | # define MAX_SHORT_BUCKET 13 |
92 | # endif |
8d063cd8 |
93 | #else |
c2a5c2d2 |
94 | # define RSLOP 0 |
8d063cd8 |
95 | #endif |
96 | |
cf5c4ad8 |
97 | #ifdef PACK_MALLOC |
98 | /* |
99 | * In this case it is assumed that if we do sbrk() in 2K units, we |
100 | * will get 2K aligned blocks. The bucket number of the given subblock is |
101 | * on the boundary of 2K block which contains the subblock. |
102 | * Several following bytes contain the magic numbers for the subblocks |
103 | * in the block. |
104 | * |
105 | * Sizes of chunks are powers of 2 for chunks in buckets <= |
106 | * MAX_PACKED, after this they are (2^n - sizeof(union overhead)) (to |
107 | * get alignment right). |
108 | * |
109 | * We suppose that starts of all the chunks in a 2K block are in |
110 | * different 2^n-byte-long chunks. If the top of the last chunk is |
111 | * aligned on a boundary of 2K block, this means that |
112 | * sizeof(union overhead)*"number of chunks" < 2^n, or |
113 | * sizeof(union overhead)*2K < 4^n, or n > 6 + log2(sizeof()/2)/2, if a |
114 | * chunk of size 2^n - overhead is used. Since this rules out n = 7 |
115 | * for 8 byte alignment, we specialcase allocation of the first of 16 |
116 | * 128-byte-long chunks. |
117 | * |
118 | * Note that with the above assumption we automatically have enough |
119 | * place for MAGIC at the start of 2K block. Note also that we |
120 | * overlay union overhead over the chunk, thus the start of the chunk |
121 | * is immediately overwritten after freeing. |
122 | */ |
123 | # define MAX_PACKED 6 |
124 | # define MAX_2_POT_ALGO ((1<<(MAX_PACKED + 1)) - M_OVERHEAD) |
125 | # define TWOK_MASK ((1<<11) - 1) |
ff68c719 |
126 | # define TWOK_MASKED(x) ((u_int)(x) & ~TWOK_MASK) |
127 | # define TWOK_SHIFT(x) ((u_int)(x) & TWOK_MASK) |
cf5c4ad8 |
128 | # define OV_INDEXp(block) ((u_char*)(TWOK_MASKED(block))) |
129 | # define OV_INDEX(block) (*OV_INDEXp(block)) |
130 | # define OV_MAGIC(block,bucket) (*(OV_INDEXp(block) + \ |
131 | (TWOK_SHIFT(block)>>(bucket + 3)) + \ |
132 | (bucket > MAX_NONSHIFT ? 1 : 0))) |
133 | # define CHUNK_SHIFT 0 |
134 | |
135 | static u_char n_blks[11 - 3] = {224, 120, 62, 31, 16, 8, 4, 2}; |
136 | static u_short blk_shift[11 - 3] = {256, 128, 64, 32, |
137 | 16*sizeof(union overhead), |
138 | 8*sizeof(union overhead), |
139 | 4*sizeof(union overhead), |
140 | 2*sizeof(union overhead), |
141 | # define MAX_NONSHIFT 2 /* Shift 64 greater than chunk 32. */ |
142 | }; |
143 | |
cf5c4ad8 |
144 | #else /* !PACK_MALLOC */ |
145 | |
146 | # define OV_MAGIC(block,bucket) (block)->ov_magic |
147 | # define OV_INDEX(block) (block)->ov_index |
148 | # define CHUNK_SHIFT 1 |
149 | #endif /* !PACK_MALLOC */ |
150 | |
151 | # define M_OVERHEAD (sizeof(union overhead) + RSLOP) |
152 | |
8d063cd8 |
153 | /* |
55497cff |
154 | * Big allocations are often of the size 2^n bytes. To make them a |
155 | * little bit better, make blocks of size 2^n+pagesize for big n. |
156 | */ |
157 | |
158 | #ifdef TWO_POT_OPTIMIZE |
159 | |
5f05dabc |
160 | # ifndef PERL_PAGESIZE |
161 | # define PERL_PAGESIZE 4096 |
162 | # endif |
163 | # ifndef FIRST_BIG_TWO_POT |
164 | # define FIRST_BIG_TWO_POT 14 /* 16K */ |
165 | # endif |
55497cff |
166 | # define FIRST_BIG_BLOCK (1<<FIRST_BIG_TWO_POT) /* 16K */ |
167 | /* If this value or more, check against bigger blocks. */ |
168 | # define FIRST_BIG_BOUND (FIRST_BIG_BLOCK - M_OVERHEAD) |
169 | /* If less than this value, goes into 2^n-overhead-block. */ |
170 | # define LAST_SMALL_BOUND ((FIRST_BIG_BLOCK>>1) - M_OVERHEAD) |
171 | |
172 | #endif /* TWO_POT_OPTIMIZE */ |
173 | |
72e5b9db |
174 | #if defined(PERL_EMERGENCY_SBRK) && defined(PERL_CORE) |
55497cff |
175 | |
176 | #ifndef BIG_SIZE |
177 | # define BIG_SIZE (1<<16) /* 64K */ |
178 | #endif |
179 | |
180 | static char *emergency_buffer; |
181 | static MEM_SIZE emergency_buffer_size; |
182 | |
183 | static char * |
184 | emergency_sbrk(size) |
185 | MEM_SIZE size; |
186 | { |
187 | if (size >= BIG_SIZE) { |
188 | /* Give the possibility to recover: */ |
189 | die("Out of memory during request for %i bytes", size); |
190 | /* croak may eat too much memory. */ |
191 | } |
192 | |
193 | if (!emergency_buffer) { |
194 | /* First offense, give a possibility to recover by dieing. */ |
195 | /* No malloc involved here: */ |
196 | GV **gvp = (GV**)hv_fetch(defstash, "^M", 2, 0); |
197 | SV *sv; |
198 | char *pv; |
199 | |
200 | if (!gvp) gvp = (GV**)hv_fetch(defstash, "\015", 1, 0); |
201 | if (!gvp || !(sv = GvSV(*gvp)) || !SvPOK(sv) |
202 | || (SvLEN(sv) < (1<<11) - M_OVERHEAD)) |
203 | return (char *)-1; /* Now die die die... */ |
204 | |
205 | /* Got it, now detach SvPV: */ |
bbce6d69 |
206 | pv = SvPV(sv, na); |
55497cff |
207 | /* Check alignment: */ |
ff68c719 |
208 | if (((u_int)(pv - M_OVERHEAD)) & ((1<<11) - 1)) { |
55497cff |
209 | PerlIO_puts(PerlIO_stderr(),"Bad alignment of $^M!\n"); |
bbce6d69 |
210 | return (char *)-1; /* die die die */ |
55497cff |
211 | } |
212 | |
213 | emergency_buffer = pv - M_OVERHEAD; |
214 | emergency_buffer_size = SvLEN(sv) + M_OVERHEAD; |
215 | SvPOK_off(sv); |
216 | SvREADONLY_on(sv); |
217 | die("Out of memory!"); /* croak may eat too much memory. */ |
ff68c719 |
218 | } |
219 | else if (emergency_buffer_size >= size) { |
55497cff |
220 | emergency_buffer_size -= size; |
221 | return emergency_buffer + emergency_buffer_size; |
222 | } |
223 | |
224 | return (char *)-1; /* poor guy... */ |
225 | } |
226 | |
72e5b9db |
227 | #else /* !(defined(TWO_POT_OPTIMIZE) && defined(PERL_CORE)) */ |
55497cff |
228 | # define emergency_sbrk(size) -1 |
72e5b9db |
229 | #endif /* !(defined(TWO_POT_OPTIMIZE) && defined(PERL_CORE)) */ |
55497cff |
230 | |
231 | /* |
8d063cd8 |
232 | * nextf[i] is the pointer to the next free block of size 2^(i+3). The |
233 | * smallest allocatable block is 8 bytes. The overhead information |
234 | * precedes the data area returned to the user. |
235 | */ |
236 | #define NBUCKETS 30 |
237 | static union overhead *nextf[NBUCKETS]; |
cf5c4ad8 |
238 | |
239 | #ifdef USE_PERL_SBRK |
240 | #define sbrk(a) Perl_sbrk(a) |
241 | char * Perl_sbrk _((int size)); |
8ac85365 |
242 | #else |
243 | #ifdef DONT_DECLARE_STD |
244 | #ifdef I_UNISTD |
245 | #include <unistd.h> |
246 | #endif |
cf5c4ad8 |
247 | #else |
8ac85365 |
248 | extern char *sbrk(int); |
249 | #endif |
cf5c4ad8 |
250 | #endif |
8d063cd8 |
251 | |
c07a80fd |
252 | #ifdef DEBUGGING_MSTATS |
8d063cd8 |
253 | /* |
254 | * nmalloc[i] is the difference between the number of mallocs and frees |
255 | * for a given block size. |
256 | */ |
257 | static u_int nmalloc[NBUCKETS]; |
5f05dabc |
258 | static u_int goodsbrk; |
259 | static u_int sbrk_slack; |
260 | static u_int start_slack; |
8d063cd8 |
261 | #endif |
262 | |
760ac839 |
263 | #ifdef DEBUGGING |
4dfc412b |
264 | #define ASSERT(p) if (!(p)) botch(STRINGIFY(p)); else |
ee0007ab |
265 | static void |
8ac85365 |
266 | botch(char *s) |
8d063cd8 |
267 | { |
4dfc412b |
268 | PerlIO_printf(PerlIO_stderr(), "assertion botched: %s\n", s); |
8d063cd8 |
269 | abort(); |
270 | } |
271 | #else |
272 | #define ASSERT(p) |
273 | #endif |
274 | |
2304df62 |
275 | Malloc_t |
8ac85365 |
276 | malloc(register size_t nbytes) |
8d063cd8 |
277 | { |
278 | register union overhead *p; |
279 | register int bucket = 0; |
ee0007ab |
280 | register MEM_SIZE shiftr; |
8d063cd8 |
281 | |
c2a5c2d2 |
282 | #if defined(DEBUGGING) || defined(RCHECK) |
ee0007ab |
283 | MEM_SIZE size = nbytes; |
45d8adaa |
284 | #endif |
285 | |
043bf814 |
286 | #ifdef PERL_CORE |
55497cff |
287 | #ifdef HAS_64K_LIMIT |
45d8adaa |
288 | if (nbytes > 0xffff) { |
043bf814 |
289 | PerlIO_printf(PerlIO_stderr(), |
290 | "Allocation too large: %lx\n", (long)nbytes); |
79072805 |
291 | my_exit(1); |
45d8adaa |
292 | } |
55497cff |
293 | #endif /* HAS_64K_LIMIT */ |
45d8adaa |
294 | #ifdef DEBUGGING |
295 | if ((long)nbytes < 0) |
043bf814 |
296 | croak("panic: malloc"); |
45d8adaa |
297 | #endif |
55497cff |
298 | #endif /* PERL_CORE */ |
45d8adaa |
299 | |
11343788 |
300 | MUTEX_LOCK(&malloc_mutex); |
8d063cd8 |
301 | /* |
302 | * Convert amount of memory requested into |
303 | * closest block size stored in hash buckets |
304 | * which satisfies request. Account for |
305 | * space used per block for accounting. |
306 | */ |
cf5c4ad8 |
307 | #ifdef PACK_MALLOC |
043bf814 |
308 | if (nbytes == 0) |
309 | nbytes = 1; |
310 | else if (nbytes > MAX_2_POT_ALGO) |
cf5c4ad8 |
311 | #endif |
043bf814 |
312 | { |
55497cff |
313 | #ifdef TWO_POT_OPTIMIZE |
043bf814 |
314 | if (nbytes >= FIRST_BIG_BOUND) |
315 | nbytes -= PERL_PAGESIZE; |
55497cff |
316 | #endif |
043bf814 |
317 | nbytes += M_OVERHEAD; |
318 | nbytes = (nbytes + 3) &~ 3; |
cf5c4ad8 |
319 | } |
8d063cd8 |
320 | shiftr = (nbytes - 1) >> 2; |
321 | /* apart from this loop, this is O(1) */ |
322 | while (shiftr >>= 1) |
323 | bucket++; |
324 | /* |
325 | * If nothing in hash bucket right now, |
326 | * request more memory from the system. |
327 | */ |
328 | if (nextf[bucket] == NULL) |
329 | morecore(bucket); |
45d8adaa |
330 | if ((p = (union overhead *)nextf[bucket]) == NULL) { |
11343788 |
331 | MUTEX_UNLOCK(&malloc_mutex); |
55497cff |
332 | #ifdef PERL_CORE |
ee0007ab |
333 | if (!nomemok) { |
760ac839 |
334 | PerlIO_puts(PerlIO_stderr(),"Out of memory!\n"); |
79072805 |
335 | my_exit(1); |
ee0007ab |
336 | } |
45d8adaa |
337 | #else |
8d063cd8 |
338 | return (NULL); |
45d8adaa |
339 | #endif |
340 | } |
341 | |
55497cff |
342 | #ifdef PERL_CORE |
68dc0745 |
343 | DEBUG_m(PerlIO_printf(Perl_debug_log, "0x%lx: (%05lu) malloc %ld bytes\n", |
344 | (unsigned long)(p+1),(unsigned long)(an++),(long)size)); |
55497cff |
345 | #endif /* PERL_CORE */ |
45d8adaa |
346 | |
8d063cd8 |
347 | /* remove from linked list */ |
bf38876a |
348 | #ifdef RCHECK |
349 | if (*((int*)p) & (sizeof(union overhead) - 1)) |
760ac839 |
350 | PerlIO_printf(PerlIO_stderr(), "Corrupt malloc ptr 0x%lx at 0x%lx\n", |
a0d0e21e |
351 | (unsigned long)*((int*)p),(unsigned long)p); |
bf38876a |
352 | #endif |
353 | nextf[bucket] = p->ov_next; |
cf5c4ad8 |
354 | OV_MAGIC(p, bucket) = MAGIC; |
355 | #ifndef PACK_MALLOC |
356 | OV_INDEX(p) = bucket; |
357 | #endif |
8d063cd8 |
358 | #ifdef RCHECK |
359 | /* |
360 | * Record allocated size of block and |
361 | * bound space with magic numbers. |
362 | */ |
c2a5c2d2 |
363 | nbytes = (size + M_OVERHEAD + 3) &~ 3; |
8d063cd8 |
364 | if (nbytes <= 0x10000) |
365 | p->ov_size = nbytes - 1; |
366 | p->ov_rmagic = RMAGIC; |
367 | *((u_int *)((caddr_t)p + nbytes - RSLOP)) = RMAGIC; |
368 | #endif |
11343788 |
369 | MUTEX_UNLOCK(&malloc_mutex); |
cf5c4ad8 |
370 | return ((Malloc_t)(p + CHUNK_SHIFT)); |
8d063cd8 |
371 | } |
372 | |
373 | /* |
374 | * Allocate more memory to the indicated bucket. |
375 | */ |
a0d0e21e |
376 | static void |
8ac85365 |
377 | morecore(register int bucket) |
8d063cd8 |
378 | { |
72aaf631 |
379 | register union overhead *ovp; |
8d063cd8 |
380 | register int rnu; /* 2^rnu bytes will be requested */ |
381 | register int nblks; /* become nblks blocks of the desired size */ |
bbce6d69 |
382 | register MEM_SIZE siz, needed; |
cf5c4ad8 |
383 | int slack = 0; |
8d063cd8 |
384 | |
385 | if (nextf[bucket]) |
386 | return; |
55497cff |
387 | if (bucket == (sizeof(MEM_SIZE)*8 - 3)) { |
388 | croak("Allocation too large"); |
389 | } |
8d063cd8 |
390 | /* |
391 | * Insure memory is allocated |
392 | * on a page boundary. Should |
393 | * make getpageize call? |
394 | */ |
ee0007ab |
395 | #ifndef atarist /* on the atari we dont have to worry about this */ |
72aaf631 |
396 | ovp = (union overhead *)sbrk(0); |
cf5c4ad8 |
397 | # ifndef I286 |
72aaf631 |
398 | if ((UV)ovp & (0x7FF >> CHUNK_SHIFT)) { |
399 | slack = (0x800 >> CHUNK_SHIFT) - ((UV)ovp & (0x7FF >> CHUNK_SHIFT)); |
c030ccd9 |
400 | (void)sbrk(slack); |
5f05dabc |
401 | # if defined(DEBUGGING_MSTATS) |
c030ccd9 |
402 | sbrk_slack += slack; |
cf5c4ad8 |
403 | # endif |
c030ccd9 |
404 | } |
cf5c4ad8 |
405 | # else |
a687059c |
406 | /* The sbrk(0) call on the I286 always returns the next segment */ |
cf5c4ad8 |
407 | # endif |
ee0007ab |
408 | #endif /* atarist */ |
a687059c |
409 | |
ee0007ab |
410 | #if !(defined(I286) || defined(atarist)) |
8d063cd8 |
411 | /* take 2k unless the block is bigger than that */ |
412 | rnu = (bucket <= 8) ? 11 : bucket + 3; |
a687059c |
413 | #else |
414 | /* take 16k unless the block is bigger than that |
ee0007ab |
415 | (80286s like large segments!), probably good on the atari too */ |
a687059c |
416 | rnu = (bucket <= 11) ? 14 : bucket + 3; |
417 | #endif |
8d063cd8 |
418 | nblks = 1 << (rnu - (bucket + 3)); /* how many blocks to get */ |
bbce6d69 |
419 | needed = (MEM_SIZE)1 << rnu; |
55497cff |
420 | #ifdef TWO_POT_OPTIMIZE |
bbce6d69 |
421 | needed += (bucket >= (FIRST_BIG_TWO_POT - 3) ? PERL_PAGESIZE : 0); |
55497cff |
422 | #endif |
72aaf631 |
423 | ovp = (union overhead *)sbrk(needed); |
8d063cd8 |
424 | /* no more room! */ |
72aaf631 |
425 | if (ovp == (union overhead *)-1) { |
426 | ovp = (union overhead *)emergency_sbrk(needed); |
427 | if (ovp == (union overhead *)-1) |
8d063cd8 |
428 | return; |
ff68c719 |
429 | } |
5f05dabc |
430 | #ifdef DEBUGGING_MSTATS |
431 | goodsbrk += needed; |
432 | #endif |
8d063cd8 |
433 | /* |
434 | * Round up to minimum allocation size boundary |
435 | * and deduct from block count to reflect. |
436 | */ |
a687059c |
437 | #ifndef I286 |
cf5c4ad8 |
438 | # ifdef PACK_MALLOC |
72aaf631 |
439 | if ((UV)ovp & 0x7FF) |
cf5c4ad8 |
440 | croak("panic: Off-page sbrk"); |
441 | # endif |
72aaf631 |
442 | if ((UV)ovp & 7) { |
443 | ovp = (union overhead *)(((UV)ovp + 8) & ~7); |
8d063cd8 |
444 | nblks--; |
445 | } |
a687059c |
446 | #else |
447 | /* Again, this should always be ok on an 80286 */ |
448 | #endif |
8d063cd8 |
449 | /* |
450 | * Add new memory allocated to that on |
451 | * free list for this hash bucket. |
452 | */ |
8d063cd8 |
453 | siz = 1 << (bucket + 3); |
cf5c4ad8 |
454 | #ifdef PACK_MALLOC |
72aaf631 |
455 | *(u_char*)ovp = bucket; /* Fill index. */ |
cf5c4ad8 |
456 | if (bucket <= MAX_PACKED - 3) { |
72aaf631 |
457 | ovp = (union overhead *) ((char*)ovp + blk_shift[bucket]); |
cf5c4ad8 |
458 | nblks = n_blks[bucket]; |
459 | # ifdef DEBUGGING_MSTATS |
460 | start_slack += blk_shift[bucket]; |
461 | # endif |
462 | } else if (bucket <= 11 - 1 - 3) { |
72aaf631 |
463 | ovp = (union overhead *) ((char*)ovp + blk_shift[bucket]); |
cf5c4ad8 |
464 | /* nblks = n_blks[bucket]; */ |
465 | siz -= sizeof(union overhead); |
72aaf631 |
466 | } else ovp++; /* One chunk per block. */ |
cf5c4ad8 |
467 | #endif /* !PACK_MALLOC */ |
72aaf631 |
468 | nextf[bucket] = ovp; |
5f05dabc |
469 | #ifdef DEBUGGING_MSTATS |
470 | nmalloc[bucket] += nblks; |
471 | #endif |
8d063cd8 |
472 | while (--nblks > 0) { |
72aaf631 |
473 | ovp->ov_next = (union overhead *)((caddr_t)ovp + siz); |
474 | ovp = (union overhead *)((caddr_t)ovp + siz); |
8d063cd8 |
475 | } |
8595d6f1 |
476 | /* Not all sbrks return zeroed memory.*/ |
72aaf631 |
477 | ovp->ov_next = (union overhead *)NULL; |
cf5c4ad8 |
478 | #ifdef PACK_MALLOC |
479 | if (bucket == 7 - 3) { /* Special case, explanation is above. */ |
480 | union overhead *n_op = nextf[7 - 3]->ov_next; |
481 | nextf[7 - 3] = (union overhead *)((caddr_t)nextf[7 - 3] |
482 | - sizeof(union overhead)); |
483 | nextf[7 - 3]->ov_next = n_op; |
484 | } |
485 | #endif /* !PACK_MALLOC */ |
8d063cd8 |
486 | } |
487 | |
94b6baf5 |
488 | Free_t |
8ac85365 |
489 | free(void *mp) |
8d063cd8 |
490 | { |
ee0007ab |
491 | register MEM_SIZE size; |
72aaf631 |
492 | register union overhead *ovp; |
352d5a3a |
493 | char *cp = (char*)mp; |
cf5c4ad8 |
494 | #ifdef PACK_MALLOC |
495 | u_char bucket; |
496 | #endif |
8d063cd8 |
497 | |
55497cff |
498 | #ifdef PERL_CORE |
68dc0745 |
499 | DEBUG_m(PerlIO_printf(Perl_debug_log, "0x%lx: (%05lu) free\n",(unsigned long)cp,(unsigned long)(an++))); |
55497cff |
500 | #endif /* PERL_CORE */ |
45d8adaa |
501 | |
cf5c4ad8 |
502 | if (cp == NULL) |
503 | return; |
72aaf631 |
504 | ovp = (union overhead *)((caddr_t)cp |
505 | - sizeof (union overhead) * CHUNK_SHIFT); |
cf5c4ad8 |
506 | #ifdef PACK_MALLOC |
72aaf631 |
507 | bucket = OV_INDEX(ovp); |
cf5c4ad8 |
508 | #endif |
72aaf631 |
509 | if (OV_MAGIC(ovp, bucket) != MAGIC) { |
68dc0745 |
510 | static int bad_free_warn = -1; |
cf5c4ad8 |
511 | if (bad_free_warn == -1) { |
512 | char *pbf = getenv("PERL_BADFREE"); |
513 | bad_free_warn = (pbf) ? atoi(pbf) : 1; |
514 | } |
515 | if (!bad_free_warn) |
516 | return; |
8990e307 |
517 | #ifdef RCHECK |
a687059c |
518 | warn("%s free() ignored", |
72aaf631 |
519 | ovp->ov_rmagic == RMAGIC - 1 ? "Duplicate" : "Bad"); |
8990e307 |
520 | #else |
521 | warn("Bad free() ignored"); |
522 | #endif |
8d063cd8 |
523 | return; /* sanity */ |
378cc40b |
524 | } |
11343788 |
525 | MUTEX_LOCK(&malloc_mutex); |
8d063cd8 |
526 | #ifdef RCHECK |
72aaf631 |
527 | ASSERT(ovp->ov_rmagic == RMAGIC); |
528 | if (OV_INDEX(ovp) <= MAX_SHORT_BUCKET) |
529 | ASSERT(*(u_int *)((caddr_t)ovp + ovp->ov_size + 1 - RSLOP) == RMAGIC); |
530 | ovp->ov_rmagic = RMAGIC - 1; |
8d063cd8 |
531 | #endif |
72aaf631 |
532 | ASSERT(OV_INDEX(ovp) < NBUCKETS); |
533 | size = OV_INDEX(ovp); |
534 | ovp->ov_next = nextf[size]; |
535 | nextf[size] = ovp; |
11343788 |
536 | MUTEX_UNLOCK(&malloc_mutex); |
8d063cd8 |
537 | } |
538 | |
539 | /* |
540 | * When a program attempts "storage compaction" as mentioned in the |
541 | * old malloc man page, it realloc's an already freed block. Usually |
542 | * this is the last block it freed; occasionally it might be farther |
543 | * back. We have to search all the free lists for the block in order |
544 | * to determine its bucket: 1st we make one pass thru the lists |
545 | * checking only the first block in each; if that fails we search |
378cc40b |
546 | * ``reall_srchlen'' blocks in each list for a match (the variable |
8d063cd8 |
547 | * is extern so the caller can modify it). If that fails we just copy |
548 | * however many bytes was given to realloc() and hope it's not huge. |
549 | */ |
378cc40b |
550 | int reall_srchlen = 4; /* 4 should be plenty, -1 =>'s whole list */ |
8d063cd8 |
551 | |
2304df62 |
552 | Malloc_t |
8ac85365 |
553 | realloc(void *mp, size_t nbytes) |
8d063cd8 |
554 | { |
ee0007ab |
555 | register MEM_SIZE onb; |
72aaf631 |
556 | union overhead *ovp; |
8d063cd8 |
557 | char *res; |
558 | register int i; |
559 | int was_alloced = 0; |
352d5a3a |
560 | char *cp = (char*)mp; |
8d063cd8 |
561 | |
45d8adaa |
562 | #ifdef DEBUGGING |
ee0007ab |
563 | MEM_SIZE size = nbytes; |
45d8adaa |
564 | #endif |
565 | |
043bf814 |
566 | #ifdef PERL_CORE |
55497cff |
567 | #ifdef HAS_64K_LIMIT |
45d8adaa |
568 | if (nbytes > 0xffff) { |
043bf814 |
569 | PerlIO_printf(PerlIO_stderr(), |
570 | "Reallocation too large: %lx\n", size); |
79072805 |
571 | my_exit(1); |
45d8adaa |
572 | } |
55497cff |
573 | #endif /* HAS_64K_LIMIT */ |
45d8adaa |
574 | if (!cp) |
ee0007ab |
575 | return malloc(nbytes); |
45d8adaa |
576 | #ifdef DEBUGGING |
577 | if ((long)nbytes < 0) |
463ee0b2 |
578 | croak("panic: realloc"); |
45d8adaa |
579 | #endif |
55497cff |
580 | #endif /* PERL_CORE */ |
45d8adaa |
581 | |
11343788 |
582 | MUTEX_LOCK(&malloc_mutex); |
72aaf631 |
583 | ovp = (union overhead *)((caddr_t)cp |
584 | - sizeof (union overhead) * CHUNK_SHIFT); |
585 | i = OV_INDEX(ovp); |
586 | if (OV_MAGIC(ovp, i) == MAGIC) { |
55497cff |
587 | was_alloced = 1; |
8d063cd8 |
588 | } else { |
589 | /* |
590 | * Already free, doing "compaction". |
591 | * |
592 | * Search for the old block of memory on the |
593 | * free list. First, check the most common |
594 | * case (last element free'd), then (this failing) |
378cc40b |
595 | * the last ``reall_srchlen'' items free'd. |
8d063cd8 |
596 | * If all lookups fail, then assume the size of |
597 | * the memory block being realloc'd is the |
598 | * smallest possible. |
599 | */ |
72aaf631 |
600 | if ((i = findbucket(ovp, 1)) < 0 && |
601 | (i = findbucket(ovp, reall_srchlen)) < 0) |
8d063cd8 |
602 | i = 0; |
603 | } |
cf5c4ad8 |
604 | onb = (1L << (i + 3)) - |
605 | #ifdef PACK_MALLOC |
606 | (i <= (MAX_PACKED - 3) ? 0 : M_OVERHEAD) |
607 | #else |
608 | M_OVERHEAD |
609 | #endif |
55497cff |
610 | #ifdef TWO_POT_OPTIMIZE |
611 | + (i >= (FIRST_BIG_TWO_POT - 3) ? PERL_PAGESIZE : 0) |
612 | #endif |
cf5c4ad8 |
613 | ; |
55497cff |
614 | /* |
615 | * avoid the copy if same size block. |
616 | * We are not agressive with boundary cases. Note that it is |
617 | * possible for small number of cases give false negative if |
618 | * both new size and old one are in the bucket for |
619 | * FIRST_BIG_TWO_POT, but the new one is near the lower end. |
620 | */ |
8d063cd8 |
621 | if (was_alloced && |
55497cff |
622 | nbytes <= onb && (nbytes > ( (onb >> 1) - M_OVERHEAD ) |
623 | #ifdef TWO_POT_OPTIMIZE |
624 | || (i == (FIRST_BIG_TWO_POT - 3) |
625 | && nbytes >= LAST_SMALL_BOUND ) |
626 | #endif |
627 | )) { |
a687059c |
628 | #ifdef RCHECK |
629 | /* |
630 | * Record new allocated size of block and |
631 | * bound space with magic numbers. |
632 | */ |
72aaf631 |
633 | if (OV_INDEX(ovp) <= MAX_SHORT_BUCKET) { |
a687059c |
634 | /* |
635 | * Convert amount of memory requested into |
636 | * closest block size stored in hash buckets |
637 | * which satisfies request. Account for |
638 | * space used per block for accounting. |
639 | */ |
cf5c4ad8 |
640 | nbytes += M_OVERHEAD; |
a687059c |
641 | nbytes = (nbytes + 3) &~ 3; |
72aaf631 |
642 | ovp->ov_size = nbytes - 1; |
643 | *((u_int *)((caddr_t)ovp + nbytes - RSLOP)) = RMAGIC; |
a687059c |
644 | } |
645 | #endif |
45d8adaa |
646 | res = cp; |
11343788 |
647 | MUTEX_UNLOCK(&malloc_mutex); |
a687059c |
648 | } |
45d8adaa |
649 | else { |
11343788 |
650 | MUTEX_UNLOCK(&malloc_mutex); |
45d8adaa |
651 | if ((res = (char*)malloc(nbytes)) == NULL) |
652 | return (NULL); |
653 | if (cp != res) /* common optimization */ |
ee0007ab |
654 | Copy(cp, res, (MEM_SIZE)(nbytes<onb?nbytes:onb), char); |
45d8adaa |
655 | if (was_alloced) |
656 | free(cp); |
657 | } |
658 | |
55497cff |
659 | #ifdef PERL_CORE |
45d8adaa |
660 | #ifdef DEBUGGING |
a0d0e21e |
661 | if (debug & 128) { |
fb73857a |
662 | PerlIO_printf(Perl_debug_log, "0x%lx: (%05lu) rfree\n",(unsigned long)res,(unsigned long)(an++)); |
663 | PerlIO_printf(Perl_debug_log, "0x%lx: (%05lu) realloc %ld bytes\n", |
68dc0745 |
664 | (unsigned long)res,(unsigned long)(an++),(long)size); |
a0d0e21e |
665 | } |
45d8adaa |
666 | #endif |
55497cff |
667 | #endif /* PERL_CORE */ |
2304df62 |
668 | return ((Malloc_t)res); |
8d063cd8 |
669 | } |
670 | |
671 | /* |
672 | * Search ``srchlen'' elements of each free list for a block whose |
673 | * header starts at ``freep''. If srchlen is -1 search the whole list. |
674 | * Return bucket number, or -1 if not found. |
675 | */ |
ee0007ab |
676 | static int |
8ac85365 |
677 | findbucket(union overhead *freep, int srchlen) |
8d063cd8 |
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 |
8ac85365 |
694 | calloc(register size_t elements, register size_t size) |
cf5c4ad8 |
695 | { |
696 | long sz = elements * size; |
697 | Malloc_t p = malloc(sz); |
698 | |
699 | if (p) { |
700 | memset((void*)p, 0, sz); |
701 | } |
702 | return p; |
703 | } |
704 | |
c07a80fd |
705 | #ifdef DEBUGGING_MSTATS |
8d063cd8 |
706 | /* |
707 | * mstats - print out statistics about malloc |
708 | * |
709 | * Prints two lines of numbers, one showing the length of the free list |
710 | * for each size category, the second showing the number of mallocs - |
711 | * frees for each size category. |
712 | */ |
ee0007ab |
713 | void |
8ac85365 |
714 | dump_mstats(char *s) |
8d063cd8 |
715 | { |
716 | register int i, j; |
717 | register union overhead *p; |
5f05dabc |
718 | int topbucket=0, totfree=0, total=0; |
c07a80fd |
719 | u_int nfree[NBUCKETS]; |
8d063cd8 |
720 | |
c07a80fd |
721 | for (i=0; i < NBUCKETS; i++) { |
8d063cd8 |
722 | for (j = 0, p = nextf[i]; p; p = p->ov_next, j++) |
723 | ; |
c07a80fd |
724 | nfree[i] = j; |
725 | totfree += nfree[i] * (1 << (i + 3)); |
5f05dabc |
726 | total += nmalloc[i] * (1 << (i + 3)); |
727 | if (nmalloc[i]) |
c07a80fd |
728 | topbucket = i; |
729 | } |
730 | if (s) |
760ac839 |
731 | PerlIO_printf(PerlIO_stderr(), "Memory allocation statistics %s (buckets 8..%d)\n", |
c07a80fd |
732 | s, (1 << (topbucket + 3)) ); |
5f05dabc |
733 | PerlIO_printf(PerlIO_stderr(), "%8d free:", totfree); |
c07a80fd |
734 | for (i=0; i <= topbucket; i++) { |
5f05dabc |
735 | PerlIO_printf(PerlIO_stderr(), (i<5 || i==7)?" %5d": (i<9)?" %3d":" %d", nfree[i]); |
8d063cd8 |
736 | } |
5f05dabc |
737 | PerlIO_printf(PerlIO_stderr(), "\n%8d used:", total - totfree); |
c07a80fd |
738 | for (i=0; i <= topbucket; i++) { |
5f05dabc |
739 | PerlIO_printf(PerlIO_stderr(), (i<5 || i==7)?" %5d": (i<9)?" %3d":" %d", nmalloc[i] - nfree[i]); |
c07a80fd |
740 | } |
5f05dabc |
741 | PerlIO_printf(PerlIO_stderr(), "\nTotal sbrk(): %8d. Odd ends: sbrk(): %7d, malloc(): %7d bytes.\n", |
742 | goodsbrk + sbrk_slack, sbrk_slack, start_slack); |
c07a80fd |
743 | } |
744 | #else |
745 | void |
8ac85365 |
746 | dump_mstats(char *s) |
c07a80fd |
747 | { |
8d063cd8 |
748 | } |
749 | #endif |
a687059c |
750 | #endif /* lint */ |
cf5c4ad8 |
751 | |
752 | |
753 | #ifdef USE_PERL_SBRK |
754 | |
760ac839 |
755 | # ifdef NeXT |
756 | # define PERL_SBRK_VIA_MALLOC |
757 | # endif |
758 | |
759 | # ifdef PERL_SBRK_VIA_MALLOC |
72e5b9db |
760 | # if defined(HIDEMYMALLOC) || defined(EMBEDMYMALLOC) |
760ac839 |
761 | # undef malloc |
762 | # else |
72e5b9db |
763 | # include "Error: -DPERL_SBRK_VIA_MALLOC needs -D(HIDE|EMBED)MYMALLOC" |
760ac839 |
764 | # endif |
cf5c4ad8 |
765 | |
766 | /* it may seem schizophrenic to use perl's malloc and let it call system */ |
767 | /* malloc, the reason for that is only the 3.2 version of the OS that had */ |
768 | /* frequent core dumps within nxzonefreenolock. This sbrk routine put an */ |
769 | /* end to the cores */ |
770 | |
760ac839 |
771 | # define SYSTEM_ALLOC(a) malloc(a) |
cf5c4ad8 |
772 | |
760ac839 |
773 | # endif /* PERL_SBRK_VIA_MALLOC */ |
cf5c4ad8 |
774 | |
775 | static IV Perl_sbrk_oldchunk; |
776 | static long Perl_sbrk_oldsize; |
777 | |
760ac839 |
778 | # define PERLSBRK_32_K (1<<15) |
779 | # define PERLSBRK_64_K (1<<16) |
cf5c4ad8 |
780 | |
781 | char * |
782 | Perl_sbrk(size) |
783 | int size; |
784 | { |
785 | IV got; |
786 | int small, reqsize; |
787 | |
788 | if (!size) return 0; |
55497cff |
789 | #ifdef PERL_CORE |
cf5c4ad8 |
790 | reqsize = size; /* just for the DEBUG_m statement */ |
791 | #endif |
57569e04 |
792 | #ifdef PACK_MALLOC |
793 | size = (size + 0x7ff) & ~0x7ff; |
794 | #endif |
cf5c4ad8 |
795 | if (size <= Perl_sbrk_oldsize) { |
796 | got = Perl_sbrk_oldchunk; |
797 | Perl_sbrk_oldchunk += size; |
798 | Perl_sbrk_oldsize -= size; |
799 | } else { |
800 | if (size >= PERLSBRK_32_K) { |
801 | small = 0; |
802 | } else { |
55497cff |
803 | #ifndef PERL_CORE |
cf5c4ad8 |
804 | reqsize = size; |
805 | #endif |
806 | size = PERLSBRK_64_K; |
807 | small = 1; |
808 | } |
809 | got = (IV)SYSTEM_ALLOC(size); |
57569e04 |
810 | #ifdef PACK_MALLOC |
811 | got = (got + 0x7ff) & ~0x7ff; |
812 | #endif |
cf5c4ad8 |
813 | if (small) { |
814 | /* Chunk is small, register the rest for future allocs. */ |
815 | Perl_sbrk_oldchunk = got + reqsize; |
816 | Perl_sbrk_oldsize = size - reqsize; |
817 | } |
818 | } |
819 | |
55497cff |
820 | #ifdef PERL_CORE |
fb73857a |
821 | DEBUG_m(PerlIO_printf(Perl_debug_log, "sbrk malloc size %ld (reqsize %ld), left size %ld, give addr 0x%lx\n", |
cf5c4ad8 |
822 | size, reqsize, Perl_sbrk_oldsize, got)); |
823 | #endif |
824 | |
825 | return (void *)got; |
826 | } |
827 | |
828 | #endif /* ! defined USE_PERL_SBRK */ |