Commit | Line | Data |
---|---|---|
a0d0e21e | 1 | /* malloc.c |
8d063cd8 | 2 | * |
8d063cd8 LW |
3 | */ |
4 | ||
87c6202a IZ |
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 | ||
38ac2dc8 DD |
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. | |
87c6202a IZ |
60 | PERL_SBRK_VIA_MALLOC undef |
61 | ||
38ac2dc8 DD |
62 | # Which allocator to use if PERL_SBRK_VIA_MALLOC |
63 | SYSTEM_ALLOC(a) malloc(a) | |
64 | ||
87c6202a IZ |
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 | ||
28ac10b1 IZ |
104 | # Some configurations may ask for 12-byte-or-so allocations which |
105 | # require 8-byte alignment (?!). In such situation one needs to | |
106 | # define this to disable 12-byte bucket (will increase memory footprint) | |
107 | STRICT_ALIGNMENT undef | |
108 | ||
87c6202a IZ |
109 | This implementation assumes that calling PerlIO_printf() does not |
110 | result in any memory allocation calls (used during a panic). | |
111 | ||
112 | */ | |
113 | ||
e8bc2b5c GS |
114 | #ifndef NO_FANCY_MALLOC |
115 | # ifndef SMALL_BUCKET_VIA_TABLE | |
116 | # define SMALL_BUCKET_VIA_TABLE | |
117 | # endif | |
118 | # ifndef BUCKETS_ROOT2 | |
119 | # define BUCKETS_ROOT2 | |
120 | # endif | |
121 | # ifndef IGNORE_SMALL_BAD_FREE | |
122 | # define IGNORE_SMALL_BAD_FREE | |
123 | # endif | |
3562ef9b IZ |
124 | #endif |
125 | ||
e8bc2b5c GS |
126 | #ifndef PLAIN_MALLOC /* Bulk enable features */ |
127 | # ifndef PACK_MALLOC | |
128 | # define PACK_MALLOC | |
129 | # endif | |
130 | # ifndef TWO_POT_OPTIMIZE | |
131 | # define TWO_POT_OPTIMIZE | |
132 | # endif | |
d720c441 IZ |
133 | # if defined(PERL_CORE) && !defined(PERL_EMERGENCY_SBRK) |
134 | # define PERL_EMERGENCY_SBRK | |
e8bc2b5c GS |
135 | # endif |
136 | # if defined(PERL_CORE) && !defined(DEBUGGING_MSTATS) | |
137 | # define DEBUGGING_MSTATS | |
138 | # endif | |
139 | #endif | |
140 | ||
141 | #define MIN_BUC_POW2 (sizeof(void*) > 4 ? 3 : 2) /* Allow for 4-byte arena. */ | |
142 | #define MIN_BUCKET (MIN_BUC_POW2 * BUCKETS_PER_POW2) | |
143 | ||
144 | #if !(defined(I286) || defined(atarist)) | |
145 | /* take 2k unless the block is bigger than that */ | |
146 | # define LOG_OF_MIN_ARENA 11 | |
147 | #else | |
148 | /* take 16k unless the block is bigger than that | |
149 | (80286s like large segments!), probably good on the atari too */ | |
150 | # define LOG_OF_MIN_ARENA 14 | |
151 | #endif | |
152 | ||
8d063cd8 | 153 | #ifndef lint |
1944739a IZ |
154 | # if defined(DEBUGGING) && !defined(NO_RCHECK) |
155 | # define RCHECK | |
156 | # endif | |
e8bc2b5c GS |
157 | # if defined(RCHECK) && defined(IGNORE_SMALL_BAD_FREE) |
158 | # undef IGNORE_SMALL_BAD_FREE | |
159 | # endif | |
8d063cd8 LW |
160 | /* |
161 | * malloc.c (Caltech) 2/21/82 | |
162 | * Chris Kingsley, kingsley@cit-20. | |
163 | * | |
164 | * This is a very fast storage allocator. It allocates blocks of a small | |
165 | * number of different sizes, and keeps free lists of each size. Blocks that | |
166 | * don't exactly fit are passed up to the next larger size. In this | |
167 | * implementation, the available sizes are 2^n-4 (or 2^n-12) bytes long. | |
cf5c4ad8 | 168 | * If PACK_MALLOC is defined, small blocks are 2^n bytes long. |
8d063cd8 LW |
169 | * This is designed for use in a program that uses vast quantities of memory, |
170 | * but bombs when it runs out. | |
171 | */ | |
172 | ||
d720c441 IZ |
173 | #ifdef PERL_CORE |
174 | # include "EXTERN.h" | |
175 | # include "perl.h" | |
176 | #else | |
177 | # ifdef PERL_FOR_X2P | |
178 | # include "../EXTERN.h" | |
179 | # include "../perl.h" | |
180 | # else | |
181 | # include <stdlib.h> | |
182 | # include <stdio.h> | |
183 | # include <memory.h> | |
184 | # define _(arg) arg | |
185 | # ifndef Malloc_t | |
186 | # define Malloc_t void * | |
187 | # endif | |
188 | # ifndef MEM_SIZE | |
189 | # define MEM_SIZE unsigned long | |
190 | # endif | |
191 | # ifndef LONG_MAX | |
192 | # define LONG_MAX 0x7FFFFFFF | |
193 | # endif | |
194 | # ifndef UV | |
195 | # define UV unsigned long | |
196 | # endif | |
197 | # ifndef caddr_t | |
198 | # define caddr_t char * | |
199 | # endif | |
200 | # ifndef Free_t | |
201 | # define Free_t void | |
202 | # endif | |
203 | # define Copy(s,d,n,t) (void)memcpy((char*)(d),(char*)(s), (n) * sizeof(t)) | |
204 | # define PerlEnv_getenv getenv | |
205 | # define PerlIO_printf fprintf | |
206 | # define PerlIO_stderr() stderr | |
207 | # endif | |
e8bc2b5c | 208 | # ifndef croak /* make depend */ |
d720c441 IZ |
209 | # define croak(mess, arg) warn((mess), (arg)); exit(1); |
210 | # endif | |
211 | # ifndef warn | |
212 | # define warn(mess, arg) fprintf(stderr, (mess), (arg)); | |
e8bc2b5c GS |
213 | # endif |
214 | # ifdef DEBUG_m | |
215 | # undef DEBUG_m | |
216 | # endif | |
217 | # define DEBUG_m(a) | |
218 | # ifdef DEBUGGING | |
219 | # undef DEBUGGING | |
220 | # endif | |
221 | #endif | |
222 | ||
223 | #ifndef MUTEX_LOCK | |
224 | # define MUTEX_LOCK(l) | |
225 | #endif | |
226 | ||
227 | #ifndef MUTEX_UNLOCK | |
228 | # define MUTEX_UNLOCK(l) | |
229 | #endif | |
230 | ||
760ac839 | 231 | #ifdef DEBUGGING |
e8bc2b5c | 232 | # undef DEBUG_m |
4a33f861 | 233 | # define DEBUG_m(a) if (PL_debug & 128) a |
760ac839 LW |
234 | #endif |
235 | ||
135863df AB |
236 | /* I don't much care whether these are defined in sys/types.h--LAW */ |
237 | ||
238 | #define u_char unsigned char | |
239 | #define u_int unsigned int | |
e8bc2b5c GS |
240 | |
241 | #ifdef HAS_QUAD | |
242 | # define u_bigint UV /* Needs to eat *void. */ | |
243 | #else /* needed? */ | |
244 | # define u_bigint unsigned long /* Needs to eat *void. */ | |
245 | #endif | |
246 | ||
135863df | 247 | #define u_short unsigned short |
8d063cd8 | 248 | |
cf5c4ad8 | 249 | /* 286 and atarist like big chunks, which gives too much overhead. */ |
250 | #if (defined(RCHECK) || defined(I286) || defined(atarist)) && defined(PACK_MALLOC) | |
e8bc2b5c | 251 | # undef PACK_MALLOC |
cf5c4ad8 | 252 | #endif |
253 | ||
8d063cd8 | 254 | /* |
cf5c4ad8 | 255 | * The description below is applicable if PACK_MALLOC is not defined. |
256 | * | |
8d063cd8 LW |
257 | * The overhead on a block is at least 4 bytes. When free, this space |
258 | * contains a pointer to the next free block, and the bottom two bits must | |
259 | * be zero. When in use, the first byte is set to MAGIC, and the second | |
260 | * byte is the size index. The remaining bytes are for alignment. | |
261 | * If range checking is enabled and the size of the block fits | |
262 | * in two bytes, then the top two bytes hold the size of the requested block | |
263 | * plus the range checking words, and the header word MINUS ONE. | |
264 | */ | |
265 | union overhead { | |
266 | union overhead *ov_next; /* when free */ | |
85e6fe83 | 267 | #if MEM_ALIGNBYTES > 4 |
c623bd54 | 268 | double strut; /* alignment problems */ |
a687059c | 269 | #endif |
8d063cd8 LW |
270 | struct { |
271 | u_char ovu_magic; /* magic number */ | |
272 | u_char ovu_index; /* bucket # */ | |
273 | #ifdef RCHECK | |
274 | u_short ovu_size; /* actual block size */ | |
275 | u_int ovu_rmagic; /* range magic number */ | |
276 | #endif | |
277 | } ovu; | |
278 | #define ov_magic ovu.ovu_magic | |
279 | #define ov_index ovu.ovu_index | |
280 | #define ov_size ovu.ovu_size | |
281 | #define ov_rmagic ovu.ovu_rmagic | |
282 | }; | |
283 | ||
760ac839 | 284 | #ifdef DEBUGGING |
d720c441 | 285 | static void botch _((char *diag, char *s)); |
a0d0e21e LW |
286 | #endif |
287 | static void morecore _((int bucket)); | |
288 | static int findbucket _((union overhead *freep, int srchlen)); | |
28ac10b1 | 289 | static void add_to_chain(void *p, MEM_SIZE size, MEM_SIZE chip); |
a0d0e21e | 290 | |
8d063cd8 LW |
291 | #define MAGIC 0xff /* magic # on accounting info */ |
292 | #define RMAGIC 0x55555555 /* magic # on range info */ | |
e8bc2b5c GS |
293 | #define RMAGIC_C 0x55 /* magic # on range info */ |
294 | ||
8d063cd8 | 295 | #ifdef RCHECK |
c2a5c2d2 IZ |
296 | # define RSLOP sizeof (u_int) |
297 | # ifdef TWO_POT_OPTIMIZE | |
e8bc2b5c | 298 | # define MAX_SHORT_BUCKET (12 * BUCKETS_PER_POW2) |
c2a5c2d2 | 299 | # else |
e8bc2b5c | 300 | # define MAX_SHORT_BUCKET (13 * BUCKETS_PER_POW2) |
c2a5c2d2 | 301 | # endif |
8d063cd8 | 302 | #else |
c2a5c2d2 | 303 | # define RSLOP 0 |
8d063cd8 LW |
304 | #endif |
305 | ||
e8bc2b5c GS |
306 | #if !defined(PACK_MALLOC) && defined(BUCKETS_ROOT2) |
307 | # undef BUCKETS_ROOT2 | |
308 | #endif | |
309 | ||
310 | #ifdef BUCKETS_ROOT2 | |
311 | # define BUCKET_TABLE_SHIFT 2 | |
312 | # define BUCKET_POW2_SHIFT 1 | |
313 | # define BUCKETS_PER_POW2 2 | |
314 | #else | |
315 | # define BUCKET_TABLE_SHIFT MIN_BUC_POW2 | |
316 | # define BUCKET_POW2_SHIFT 0 | |
317 | # define BUCKETS_PER_POW2 1 | |
318 | #endif | |
319 | ||
274c7500 IZ |
320 | #if !defined(MEM_ALIGNBYTES) || ((MEM_ALIGNBYTES > 4) && !defined(STRICT_ALIGNMENT)) |
321 | /* Figure out the alignment of void*. */ | |
322 | struct aligner { | |
323 | char c; | |
324 | void *p; | |
325 | }; | |
326 | # define ALIGN_SMALL ((int)((caddr_t)&(((struct aligner*)0)->p))) | |
327 | #else | |
328 | # define ALIGN_SMALL MEM_ALIGNBYTES | |
329 | #endif | |
330 | ||
331 | #define IF_ALIGN_8(yes,no) ((ALIGN_SMALL>4) ? (yes) : (no)) | |
332 | ||
e8bc2b5c GS |
333 | #ifdef BUCKETS_ROOT2 |
334 | # define MAX_BUCKET_BY_TABLE 13 | |
335 | static u_short buck_size[MAX_BUCKET_BY_TABLE + 1] = | |
336 | { | |
337 | 0, 0, 0, 0, 4, 4, 8, 12, 16, 24, 32, 48, 64, 80, | |
338 | }; | |
339 | # define BUCKET_SIZE(i) ((i) % 2 ? buck_size[i] : (1 << ((i) >> BUCKET_POW2_SHIFT))) | |
340 | # define BUCKET_SIZE_REAL(i) ((i) <= MAX_BUCKET_BY_TABLE \ | |
341 | ? buck_size[i] \ | |
342 | : ((1 << ((i) >> BUCKET_POW2_SHIFT)) \ | |
343 | - MEM_OVERHEAD(i) \ | |
344 | + POW2_OPTIMIZE_SURPLUS(i))) | |
345 | #else | |
346 | # define BUCKET_SIZE(i) (1 << ((i) >> BUCKET_POW2_SHIFT)) | |
347 | # define BUCKET_SIZE_REAL(i) (BUCKET_SIZE(i) - MEM_OVERHEAD(i) + POW2_OPTIMIZE_SURPLUS(i)) | |
348 | #endif | |
349 | ||
350 | ||
cf5c4ad8 | 351 | #ifdef PACK_MALLOC |
e8bc2b5c GS |
352 | /* In this case it is assumed that if we do sbrk() in 2K units, we |
353 | * will get 2K aligned arenas (at least after some initial | |
354 | * alignment). The bucket number of the given subblock is on the start | |
355 | * of 2K arena which contains the subblock. Several following bytes | |
356 | * contain the magic numbers for the subblocks in the block. | |
cf5c4ad8 | 357 | * |
358 | * Sizes of chunks are powers of 2 for chunks in buckets <= | |
359 | * MAX_PACKED, after this they are (2^n - sizeof(union overhead)) (to | |
360 | * get alignment right). | |
361 | * | |
e8bc2b5c GS |
362 | * Consider an arena for 2^n with n>MAX_PACKED. We suppose that |
363 | * starts of all the chunks in a 2K arena are in different | |
364 | * 2^n-byte-long chunks. If the top of the last chunk is aligned on a | |
365 | * boundary of 2K block, this means that sizeof(union | |
366 | * overhead)*"number of chunks" < 2^n, or sizeof(union overhead)*2K < | |
367 | * 4^n, or n > 6 + log2(sizeof()/2)/2, since a chunk of size 2^n - | |
368 | * overhead is used. Since this rules out n = 7 for 8 byte alignment, | |
369 | * we specialcase allocation of the first of 16 128-byte-long chunks. | |
cf5c4ad8 | 370 | * |
371 | * Note that with the above assumption we automatically have enough | |
372 | * place for MAGIC at the start of 2K block. Note also that we | |
e8bc2b5c GS |
373 | * overlay union overhead over the chunk, thus the start of small chunks |
374 | * is immediately overwritten after freeing. */ | |
375 | # define MAX_PACKED_POW2 6 | |
376 | # define MAX_PACKED (MAX_PACKED_POW2 * BUCKETS_PER_POW2 + BUCKET_POW2_SHIFT) | |
377 | # define MAX_POW2_ALGO ((1<<(MAX_PACKED_POW2 + 1)) - M_OVERHEAD) | |
378 | # define TWOK_MASK ((1<<LOG_OF_MIN_ARENA) - 1) | |
379 | # define TWOK_MASKED(x) ((u_bigint)(x) & ~TWOK_MASK) | |
380 | # define TWOK_SHIFT(x) ((u_bigint)(x) & TWOK_MASK) | |
cf5c4ad8 | 381 | # define OV_INDEXp(block) ((u_char*)(TWOK_MASKED(block))) |
382 | # define OV_INDEX(block) (*OV_INDEXp(block)) | |
383 | # define OV_MAGIC(block,bucket) (*(OV_INDEXp(block) + \ | |
e8bc2b5c GS |
384 | (TWOK_SHIFT(block)>> \ |
385 | (bucket>>BUCKET_POW2_SHIFT)) + \ | |
386 | (bucket >= MIN_NEEDS_SHIFT ? 1 : 0))) | |
387 | /* A bucket can have a shift smaller than it size, we need to | |
388 | shift its magic number so it will not overwrite index: */ | |
389 | # ifdef BUCKETS_ROOT2 | |
390 | # define MIN_NEEDS_SHIFT (7*BUCKETS_PER_POW2 - 1) /* Shift 80 greater than chunk 64. */ | |
391 | # else | |
392 | # define MIN_NEEDS_SHIFT (7*BUCKETS_PER_POW2) /* Shift 128 greater than chunk 32. */ | |
393 | # endif | |
cf5c4ad8 | 394 | # define CHUNK_SHIFT 0 |
395 | ||
e8bc2b5c GS |
396 | /* Number of active buckets of given ordinal. */ |
397 | #ifdef IGNORE_SMALL_BAD_FREE | |
398 | #define FIRST_BUCKET_WITH_CHECK (6 * BUCKETS_PER_POW2) /* 64 */ | |
399 | # define N_BLKS(bucket) ( (bucket) < FIRST_BUCKET_WITH_CHECK \ | |
400 | ? ((1<<LOG_OF_MIN_ARENA) - 1)/BUCKET_SIZE(bucket) \ | |
401 | : n_blks[bucket] ) | |
402 | #else | |
403 | # define N_BLKS(bucket) n_blks[bucket] | |
404 | #endif | |
405 | ||
406 | static u_short n_blks[LOG_OF_MIN_ARENA * BUCKETS_PER_POW2] = | |
407 | { | |
408 | # if BUCKETS_PER_POW2==1 | |
409 | 0, 0, | |
410 | (MIN_BUC_POW2==2 ? 384 : 0), | |
411 | 224, 120, 62, 31, 16, 8, 4, 2 | |
412 | # else | |
413 | 0, 0, 0, 0, | |
414 | (MIN_BUC_POW2==2 ? 384 : 0), (MIN_BUC_POW2==2 ? 384 : 0), /* 4, 4 */ | |
415 | 224, 149, 120, 80, 62, 41, 31, 25, 16, 16, 8, 8, 4, 4, 2, 2 | |
416 | # endif | |
417 | }; | |
418 | ||
419 | /* Shift of the first bucket with the given ordinal inside 2K chunk. */ | |
420 | #ifdef IGNORE_SMALL_BAD_FREE | |
421 | # define BLK_SHIFT(bucket) ( (bucket) < FIRST_BUCKET_WITH_CHECK \ | |
422 | ? ((1<<LOG_OF_MIN_ARENA) \ | |
423 | - BUCKET_SIZE(bucket) * N_BLKS(bucket)) \ | |
424 | : blk_shift[bucket]) | |
425 | #else | |
426 | # define BLK_SHIFT(bucket) blk_shift[bucket] | |
427 | #endif | |
428 | ||
429 | static u_short blk_shift[LOG_OF_MIN_ARENA * BUCKETS_PER_POW2] = | |
430 | { | |
431 | # if BUCKETS_PER_POW2==1 | |
432 | 0, 0, | |
433 | (MIN_BUC_POW2==2 ? 512 : 0), | |
434 | 256, 128, 64, 64, /* 8 to 64 */ | |
435 | 16*sizeof(union overhead), | |
436 | 8*sizeof(union overhead), | |
437 | 4*sizeof(union overhead), | |
438 | 2*sizeof(union overhead), | |
439 | # else | |
440 | 0, 0, 0, 0, | |
441 | (MIN_BUC_POW2==2 ? 512 : 0), (MIN_BUC_POW2==2 ? 512 : 0), | |
442 | 256, 260, 128, 128, 64, 80, 64, 48, /* 8 to 96 */ | |
443 | 16*sizeof(union overhead), 16*sizeof(union overhead), | |
444 | 8*sizeof(union overhead), 8*sizeof(union overhead), | |
445 | 4*sizeof(union overhead), 4*sizeof(union overhead), | |
446 | 2*sizeof(union overhead), 2*sizeof(union overhead), | |
447 | # endif | |
448 | }; | |
cf5c4ad8 | 449 | |
cf5c4ad8 | 450 | #else /* !PACK_MALLOC */ |
451 | ||
452 | # define OV_MAGIC(block,bucket) (block)->ov_magic | |
453 | # define OV_INDEX(block) (block)->ov_index | |
454 | # define CHUNK_SHIFT 1 | |
e8bc2b5c | 455 | # define MAX_PACKED -1 |
cf5c4ad8 | 456 | #endif /* !PACK_MALLOC */ |
457 | ||
e8bc2b5c GS |
458 | #define M_OVERHEAD (sizeof(union overhead) + RSLOP) |
459 | ||
460 | #ifdef PACK_MALLOC | |
461 | # define MEM_OVERHEAD(bucket) \ | |
462 | (bucket <= MAX_PACKED ? 0 : M_OVERHEAD) | |
463 | # ifdef SMALL_BUCKET_VIA_TABLE | |
464 | # define START_SHIFTS_BUCKET ((MAX_PACKED_POW2 + 1) * BUCKETS_PER_POW2) | |
465 | # define START_SHIFT MAX_PACKED_POW2 | |
466 | # ifdef BUCKETS_ROOT2 /* Chunks of size 3*2^n. */ | |
467 | # define SIZE_TABLE_MAX 80 | |
468 | # else | |
469 | # define SIZE_TABLE_MAX 64 | |
470 | # endif | |
471 | static char bucket_of[] = | |
472 | { | |
473 | # ifdef BUCKETS_ROOT2 /* Chunks of size 3*2^n. */ | |
474 | /* 0 to 15 in 4-byte increments. */ | |
475 | (sizeof(void*) > 4 ? 6 : 5), /* 4/8, 5-th bucket for better reports */ | |
476 | 6, /* 8 */ | |
274c7500 | 477 | IF_ALIGN_8(8,7), 8, /* 16/12, 16 */ |
e8bc2b5c GS |
478 | 9, 9, 10, 10, /* 24, 32 */ |
479 | 11, 11, 11, 11, /* 48 */ | |
480 | 12, 12, 12, 12, /* 64 */ | |
481 | 13, 13, 13, 13, /* 80 */ | |
482 | 13, 13, 13, 13 /* 80 */ | |
483 | # else /* !BUCKETS_ROOT2 */ | |
484 | /* 0 to 15 in 4-byte increments. */ | |
485 | (sizeof(void*) > 4 ? 3 : 2), | |
486 | 3, | |
487 | 4, 4, | |
488 | 5, 5, 5, 5, | |
489 | 6, 6, 6, 6, | |
490 | 6, 6, 6, 6 | |
491 | # endif /* !BUCKETS_ROOT2 */ | |
492 | }; | |
493 | # else /* !SMALL_BUCKET_VIA_TABLE */ | |
494 | # define START_SHIFTS_BUCKET MIN_BUCKET | |
495 | # define START_SHIFT (MIN_BUC_POW2 - 1) | |
496 | # endif /* !SMALL_BUCKET_VIA_TABLE */ | |
497 | #else /* !PACK_MALLOC */ | |
498 | # define MEM_OVERHEAD(bucket) M_OVERHEAD | |
499 | # ifdef SMALL_BUCKET_VIA_TABLE | |
500 | # undef SMALL_BUCKET_VIA_TABLE | |
501 | # endif | |
502 | # define START_SHIFTS_BUCKET MIN_BUCKET | |
503 | # define START_SHIFT (MIN_BUC_POW2 - 1) | |
504 | #endif /* !PACK_MALLOC */ | |
cf5c4ad8 | 505 | |
8d063cd8 | 506 | /* |
55497cff | 507 | * Big allocations are often of the size 2^n bytes. To make them a |
508 | * little bit better, make blocks of size 2^n+pagesize for big n. | |
509 | */ | |
510 | ||
511 | #ifdef TWO_POT_OPTIMIZE | |
512 | ||
5f05dabc | 513 | # ifndef PERL_PAGESIZE |
514 | # define PERL_PAGESIZE 4096 | |
515 | # endif | |
e8bc2b5c GS |
516 | # ifndef FIRST_BIG_POW2 |
517 | # define FIRST_BIG_POW2 15 /* 32K, 16K is used too often. */ | |
5f05dabc | 518 | # endif |
e8bc2b5c | 519 | # define FIRST_BIG_BLOCK (1<<FIRST_BIG_POW2) |
55497cff | 520 | /* If this value or more, check against bigger blocks. */ |
521 | # define FIRST_BIG_BOUND (FIRST_BIG_BLOCK - M_OVERHEAD) | |
522 | /* If less than this value, goes into 2^n-overhead-block. */ | |
523 | # define LAST_SMALL_BOUND ((FIRST_BIG_BLOCK>>1) - M_OVERHEAD) | |
524 | ||
e8bc2b5c GS |
525 | # define POW2_OPTIMIZE_ADJUST(nbytes) \ |
526 | ((nbytes >= FIRST_BIG_BOUND) ? nbytes -= PERL_PAGESIZE : 0) | |
527 | # define POW2_OPTIMIZE_SURPLUS(bucket) \ | |
528 | ((bucket >= FIRST_BIG_POW2 * BUCKETS_PER_POW2) ? PERL_PAGESIZE : 0) | |
529 | ||
530 | #else /* !TWO_POT_OPTIMIZE */ | |
531 | # define POW2_OPTIMIZE_ADJUST(nbytes) | |
532 | # define POW2_OPTIMIZE_SURPLUS(bucket) 0 | |
533 | #endif /* !TWO_POT_OPTIMIZE */ | |
534 | ||
535 | #if defined(HAS_64K_LIMIT) && defined(PERL_CORE) | |
536 | # define BARK_64K_LIMIT(what,nbytes,size) \ | |
537 | if (nbytes > 0xffff) { \ | |
538 | PerlIO_printf(PerlIO_stderr(), \ | |
539 | "%s too large: %lx\n", what, size); \ | |
540 | my_exit(1); \ | |
541 | } | |
542 | #else /* !HAS_64K_LIMIT || !PERL_CORE */ | |
543 | # define BARK_64K_LIMIT(what,nbytes,size) | |
544 | #endif /* !HAS_64K_LIMIT || !PERL_CORE */ | |
55497cff | 545 | |
e8bc2b5c GS |
546 | #ifndef MIN_SBRK |
547 | # define MIN_SBRK 2048 | |
548 | #endif | |
549 | ||
550 | #ifndef FIRST_SBRK | |
d720c441 | 551 | # define FIRST_SBRK (48*1024) |
e8bc2b5c GS |
552 | #endif |
553 | ||
554 | /* Minimal sbrk in percents of what is already alloced. */ | |
555 | #ifndef MIN_SBRK_FRAC | |
556 | # define MIN_SBRK_FRAC 3 | |
557 | #endif | |
558 | ||
559 | #ifndef SBRK_ALLOW_FAILURES | |
560 | # define SBRK_ALLOW_FAILURES 3 | |
561 | #endif | |
55497cff | 562 | |
e8bc2b5c GS |
563 | #ifndef SBRK_FAILURE_PRICE |
564 | # define SBRK_FAILURE_PRICE 50 | |
55497cff | 565 | #endif |
566 | ||
e8bc2b5c GS |
567 | #if defined(PERL_EMERGENCY_SBRK) && defined(PERL_CORE) |
568 | ||
569 | # ifndef BIG_SIZE | |
570 | # define BIG_SIZE (1<<16) /* 64K */ | |
571 | # endif | |
572 | ||
55497cff | 573 | static char *emergency_buffer; |
574 | static MEM_SIZE emergency_buffer_size; | |
575 | ||
52082926 | 576 | static Malloc_t |
55497cff | 577 | emergency_sbrk(size) |
578 | MEM_SIZE size; | |
579 | { | |
28ac10b1 IZ |
580 | MEM_SIZE rsize = (((size - 1)>>LOG_OF_MIN_ARENA) + 1)<<LOG_OF_MIN_ARENA; |
581 | ||
55497cff | 582 | if (size >= BIG_SIZE) { |
583 | /* Give the possibility to recover: */ | |
51dc0457 | 584 | MUTEX_UNLOCK(&PL_malloc_mutex); |
1b979e0a | 585 | croak("Out of memory during \"large\" request for %i bytes", size); |
55497cff | 586 | } |
587 | ||
28ac10b1 IZ |
588 | if (emergency_buffer_size >= rsize) { |
589 | char *old = emergency_buffer; | |
590 | ||
591 | emergency_buffer_size -= rsize; | |
592 | emergency_buffer += rsize; | |
593 | return old; | |
594 | } else { | |
18f739ee | 595 | dTHR; |
55497cff | 596 | /* First offense, give a possibility to recover by dieing. */ |
597 | /* No malloc involved here: */ | |
4a33f861 | 598 | GV **gvp = (GV**)hv_fetch(PL_defstash, "^M", 2, 0); |
55497cff | 599 | SV *sv; |
600 | char *pv; | |
28ac10b1 | 601 | int have = 0; |
55497cff | 602 | |
28ac10b1 IZ |
603 | if (emergency_buffer_size) { |
604 | add_to_chain(emergency_buffer, emergency_buffer_size, 0); | |
605 | emergency_buffer_size = 0; | |
606 | emergency_buffer = Nullch; | |
607 | have = 1; | |
608 | } | |
4a33f861 | 609 | if (!gvp) gvp = (GV**)hv_fetch(PL_defstash, "\015", 1, 0); |
55497cff | 610 | if (!gvp || !(sv = GvSV(*gvp)) || !SvPOK(sv) |
28ac10b1 IZ |
611 | || (SvLEN(sv) < (1<<LOG_OF_MIN_ARENA) - M_OVERHEAD)) { |
612 | if (have) | |
613 | goto do_croak; | |
55497cff | 614 | return (char *)-1; /* Now die die die... */ |
28ac10b1 | 615 | } |
55497cff | 616 | /* Got it, now detach SvPV: */ |
6b88bc9c | 617 | pv = SvPV(sv, PL_na); |
55497cff | 618 | /* Check alignment: */ |
28ac10b1 | 619 | if (((UV)(pv - sizeof(union overhead))) & ((1<<LOG_OF_MIN_ARENA) - 1)) { |
55497cff | 620 | PerlIO_puts(PerlIO_stderr(),"Bad alignment of $^M!\n"); |
bbce6d69 | 621 | return (char *)-1; /* die die die */ |
55497cff | 622 | } |
623 | ||
28ac10b1 IZ |
624 | emergency_buffer = pv - sizeof(union overhead); |
625 | emergency_buffer_size = malloced_size(pv) + M_OVERHEAD; | |
55497cff | 626 | SvPOK_off(sv); |
28ac10b1 IZ |
627 | SvPVX(sv) = Nullch; |
628 | SvCUR(sv) = SvLEN(sv) = 0; | |
55497cff | 629 | } |
28ac10b1 IZ |
630 | do_croak: |
631 | MUTEX_UNLOCK(&PL_malloc_mutex); | |
632 | croak("Out of memory during request for %i bytes", size); | |
55497cff | 633 | } |
634 | ||
e8bc2b5c | 635 | #else /* !(defined(PERL_EMERGENCY_SBRK) && defined(PERL_CORE)) */ |
55497cff | 636 | # define emergency_sbrk(size) -1 |
e8bc2b5c | 637 | #endif /* !(defined(PERL_EMERGENCY_SBRK) && defined(PERL_CORE)) */ |
55497cff | 638 | |
639 | /* | |
e8bc2b5c | 640 | * nextf[i] is the pointer to the next free block of size 2^i. The |
8d063cd8 LW |
641 | * smallest allocatable block is 8 bytes. The overhead information |
642 | * precedes the data area returned to the user. | |
643 | */ | |
e8bc2b5c | 644 | #define NBUCKETS (32*BUCKETS_PER_POW2 + 1) |
8d063cd8 | 645 | static union overhead *nextf[NBUCKETS]; |
cf5c4ad8 | 646 | |
647 | #ifdef USE_PERL_SBRK | |
648 | #define sbrk(a) Perl_sbrk(a) | |
52082926 | 649 | Malloc_t Perl_sbrk _((int size)); |
8ac85365 NIS |
650 | #else |
651 | #ifdef DONT_DECLARE_STD | |
652 | #ifdef I_UNISTD | |
653 | #include <unistd.h> | |
654 | #endif | |
cf5c4ad8 | 655 | #else |
52082926 | 656 | extern Malloc_t sbrk(int); |
8ac85365 | 657 | #endif |
cf5c4ad8 | 658 | #endif |
8d063cd8 | 659 | |
c07a80fd | 660 | #ifdef DEBUGGING_MSTATS |
8d063cd8 LW |
661 | /* |
662 | * nmalloc[i] is the difference between the number of mallocs and frees | |
663 | * for a given block size. | |
664 | */ | |
665 | static u_int nmalloc[NBUCKETS]; | |
5f05dabc | 666 | static u_int sbrk_slack; |
667 | static u_int start_slack; | |
8d063cd8 LW |
668 | #endif |
669 | ||
e8bc2b5c GS |
670 | static u_int goodsbrk; |
671 | ||
760ac839 | 672 | #ifdef DEBUGGING |
d720c441 | 673 | #define ASSERT(p,diag) if (!(p)) botch(diag,STRINGIFY(p)); else |
ee0007ab | 674 | static void |
d720c441 | 675 | botch(char *diag, char *s) |
8d063cd8 | 676 | { |
d720c441 | 677 | PerlIO_printf(PerlIO_stderr(), "assertion botched (%s?): %s\n", diag, s); |
3028581b | 678 | PerlProc_abort(); |
8d063cd8 LW |
679 | } |
680 | #else | |
d720c441 | 681 | #define ASSERT(p, diag) |
8d063cd8 LW |
682 | #endif |
683 | ||
2304df62 | 684 | Malloc_t |
8ac85365 | 685 | malloc(register size_t nbytes) |
8d063cd8 LW |
686 | { |
687 | register union overhead *p; | |
e8bc2b5c | 688 | register int bucket; |
ee0007ab | 689 | register MEM_SIZE shiftr; |
8d063cd8 | 690 | |
c2a5c2d2 | 691 | #if defined(DEBUGGING) || defined(RCHECK) |
ee0007ab | 692 | MEM_SIZE size = nbytes; |
45d8adaa LW |
693 | #endif |
694 | ||
e8bc2b5c | 695 | BARK_64K_LIMIT("Allocation",nbytes,nbytes); |
45d8adaa LW |
696 | #ifdef DEBUGGING |
697 | if ((long)nbytes < 0) | |
d720c441 | 698 | croak("%s", "panic: malloc"); |
45d8adaa | 699 | #endif |
45d8adaa | 700 | |
51dc0457 | 701 | MUTEX_LOCK(&PL_malloc_mutex); |
8d063cd8 LW |
702 | /* |
703 | * Convert amount of memory requested into | |
704 | * closest block size stored in hash buckets | |
705 | * which satisfies request. Account for | |
706 | * space used per block for accounting. | |
707 | */ | |
cf5c4ad8 | 708 | #ifdef PACK_MALLOC |
e8bc2b5c GS |
709 | # ifdef SMALL_BUCKET_VIA_TABLE |
710 | if (nbytes == 0) | |
711 | bucket = MIN_BUCKET; | |
712 | else if (nbytes <= SIZE_TABLE_MAX) { | |
713 | bucket = bucket_of[(nbytes - 1) >> BUCKET_TABLE_SHIFT]; | |
714 | } else | |
715 | # else | |
043bf814 RB |
716 | if (nbytes == 0) |
717 | nbytes = 1; | |
e8bc2b5c GS |
718 | if (nbytes <= MAX_POW2_ALGO) goto do_shifts; |
719 | else | |
720 | # endif | |
55497cff | 721 | #endif |
e8bc2b5c GS |
722 | { |
723 | POW2_OPTIMIZE_ADJUST(nbytes); | |
724 | nbytes += M_OVERHEAD; | |
725 | nbytes = (nbytes + 3) &~ 3; | |
726 | do_shifts: | |
727 | shiftr = (nbytes - 1) >> START_SHIFT; | |
728 | bucket = START_SHIFTS_BUCKET; | |
729 | /* apart from this loop, this is O(1) */ | |
730 | while (shiftr >>= 1) | |
731 | bucket += BUCKETS_PER_POW2; | |
cf5c4ad8 | 732 | } |
8d063cd8 LW |
733 | /* |
734 | * If nothing in hash bucket right now, | |
735 | * request more memory from the system. | |
736 | */ | |
737 | if (nextf[bucket] == NULL) | |
738 | morecore(bucket); | |
e8bc2b5c | 739 | if ((p = nextf[bucket]) == NULL) { |
51dc0457 | 740 | MUTEX_UNLOCK(&PL_malloc_mutex); |
55497cff | 741 | #ifdef PERL_CORE |
4a33f861 | 742 | if (!PL_nomemok) { |
760ac839 | 743 | PerlIO_puts(PerlIO_stderr(),"Out of memory!\n"); |
79072805 | 744 | my_exit(1); |
ee0007ab | 745 | } |
45d8adaa | 746 | #else |
8d063cd8 | 747 | return (NULL); |
45d8adaa LW |
748 | #endif |
749 | } | |
750 | ||
e8bc2b5c GS |
751 | DEBUG_m(PerlIO_printf(Perl_debug_log, |
752 | "0x%lx: (%05lu) malloc %ld bytes\n", | |
4a33f861 | 753 | (unsigned long)(p+1), (unsigned long)(PL_an++), |
e8bc2b5c | 754 | (long)size)); |
45d8adaa | 755 | |
8d063cd8 | 756 | /* remove from linked list */ |
802004fa DD |
757 | #if defined(RCHECK) |
758 | if (((UV)p) & (MEM_ALIGNBYTES - 1)) | |
760ac839 | 759 | PerlIO_printf(PerlIO_stderr(), "Corrupt malloc ptr 0x%lx at 0x%lx\n", |
a0d0e21e | 760 | (unsigned long)*((int*)p),(unsigned long)p); |
bf38876a LW |
761 | #endif |
762 | nextf[bucket] = p->ov_next; | |
e8bc2b5c GS |
763 | #ifdef IGNORE_SMALL_BAD_FREE |
764 | if (bucket >= FIRST_BUCKET_WITH_CHECK) | |
765 | #endif | |
766 | OV_MAGIC(p, bucket) = MAGIC; | |
cf5c4ad8 | 767 | #ifndef PACK_MALLOC |
768 | OV_INDEX(p) = bucket; | |
769 | #endif | |
8d063cd8 LW |
770 | #ifdef RCHECK |
771 | /* | |
772 | * Record allocated size of block and | |
773 | * bound space with magic numbers. | |
774 | */ | |
8d063cd8 | 775 | p->ov_rmagic = RMAGIC; |
e8bc2b5c GS |
776 | if (bucket <= MAX_SHORT_BUCKET) { |
777 | int i; | |
778 | ||
779 | nbytes = size + M_OVERHEAD; | |
780 | p->ov_size = nbytes - 1; | |
781 | if ((i = nbytes & 3)) { | |
782 | i = 4 - i; | |
783 | while (i--) | |
784 | *((char *)((caddr_t)p + nbytes - RSLOP + i)) = RMAGIC_C; | |
785 | } | |
786 | nbytes = (nbytes + 3) &~ 3; | |
787 | *((u_int *)((caddr_t)p + nbytes - RSLOP)) = RMAGIC; | |
788 | } | |
8d063cd8 | 789 | #endif |
51dc0457 | 790 | MUTEX_UNLOCK(&PL_malloc_mutex); |
cf5c4ad8 | 791 | return ((Malloc_t)(p + CHUNK_SHIFT)); |
8d063cd8 LW |
792 | } |
793 | ||
e8bc2b5c GS |
794 | static char *last_sbrk_top; |
795 | static char *last_op; /* This arena can be easily extended. */ | |
796 | static int sbrked_remains; | |
797 | static int sbrk_good = SBRK_ALLOW_FAILURES * SBRK_FAILURE_PRICE; | |
798 | ||
799 | #ifdef DEBUGGING_MSTATS | |
800 | static int sbrks; | |
801 | #endif | |
802 | ||
803 | struct chunk_chain_s { | |
804 | struct chunk_chain_s *next; | |
805 | MEM_SIZE size; | |
806 | }; | |
807 | static struct chunk_chain_s *chunk_chain; | |
808 | static int n_chunks; | |
809 | static char max_bucket; | |
810 | ||
811 | /* Cutoff a piece of one of the chunks in the chain. Prefer smaller chunk. */ | |
812 | static void * | |
813 | get_from_chain(MEM_SIZE size) | |
814 | { | |
815 | struct chunk_chain_s *elt = chunk_chain, **oldp = &chunk_chain; | |
816 | struct chunk_chain_s **oldgoodp = NULL; | |
817 | long min_remain = LONG_MAX; | |
818 | ||
819 | while (elt) { | |
820 | if (elt->size >= size) { | |
821 | long remains = elt->size - size; | |
822 | if (remains >= 0 && remains < min_remain) { | |
823 | oldgoodp = oldp; | |
824 | min_remain = remains; | |
825 | } | |
826 | if (remains == 0) { | |
827 | break; | |
828 | } | |
829 | } | |
830 | oldp = &( elt->next ); | |
831 | elt = elt->next; | |
832 | } | |
833 | if (!oldgoodp) return NULL; | |
834 | if (min_remain) { | |
835 | void *ret = *oldgoodp; | |
836 | struct chunk_chain_s *next = (*oldgoodp)->next; | |
837 | ||
838 | *oldgoodp = (struct chunk_chain_s *)((char*)ret + size); | |
839 | (*oldgoodp)->size = min_remain; | |
840 | (*oldgoodp)->next = next; | |
841 | return ret; | |
842 | } else { | |
843 | void *ret = *oldgoodp; | |
844 | *oldgoodp = (*oldgoodp)->next; | |
845 | n_chunks--; | |
846 | return ret; | |
847 | } | |
848 | } | |
849 | ||
850 | static void | |
851 | add_to_chain(void *p, MEM_SIZE size, MEM_SIZE chip) | |
852 | { | |
853 | struct chunk_chain_s *next = chunk_chain; | |
854 | char *cp = (char*)p; | |
855 | ||
856 | cp += chip; | |
857 | chunk_chain = (struct chunk_chain_s *)cp; | |
858 | chunk_chain->size = size - chip; | |
859 | chunk_chain->next = next; | |
860 | n_chunks++; | |
861 | } | |
862 | ||
863 | static void * | |
864 | get_from_bigger_buckets(int bucket, MEM_SIZE size) | |
865 | { | |
866 | int price = 1; | |
867 | static int bucketprice[NBUCKETS]; | |
868 | while (bucket <= max_bucket) { | |
869 | /* We postpone stealing from bigger buckets until we want it | |
870 | often enough. */ | |
871 | if (nextf[bucket] && bucketprice[bucket]++ >= price) { | |
872 | /* Steal it! */ | |
873 | void *ret = (void*)(nextf[bucket] - 1 + CHUNK_SHIFT); | |
874 | bucketprice[bucket] = 0; | |
875 | if (((char*)nextf[bucket]) - M_OVERHEAD == last_op) { | |
876 | last_op = NULL; /* Disable optimization */ | |
877 | } | |
878 | nextf[bucket] = nextf[bucket]->ov_next; | |
879 | #ifdef DEBUGGING_MSTATS | |
880 | nmalloc[bucket]--; | |
881 | start_slack -= M_OVERHEAD; | |
882 | #endif | |
883 | add_to_chain(ret, (BUCKET_SIZE(bucket) + | |
884 | POW2_OPTIMIZE_SURPLUS(bucket)), | |
885 | size); | |
886 | return ret; | |
887 | } | |
888 | bucket++; | |
889 | } | |
890 | return NULL; | |
891 | } | |
892 | ||
fa423c5b IZ |
893 | static union overhead * |
894 | getpages(int needed, int *nblksp, int bucket) | |
895 | { | |
896 | /* Need to do (possibly expensive) system call. Try to | |
897 | optimize it for rare calling. */ | |
898 | MEM_SIZE require = needed - sbrked_remains; | |
899 | char *cp; | |
900 | union overhead *ovp; | |
901 | int slack = 0; | |
902 | ||
903 | if (sbrk_good > 0) { | |
904 | if (!last_sbrk_top && require < FIRST_SBRK) | |
905 | require = FIRST_SBRK; | |
906 | else if (require < MIN_SBRK) require = MIN_SBRK; | |
907 | ||
908 | if (require < goodsbrk * MIN_SBRK_FRAC / 100) | |
909 | require = goodsbrk * MIN_SBRK_FRAC / 100; | |
910 | require = ((require - 1 + MIN_SBRK) / MIN_SBRK) * MIN_SBRK; | |
911 | } else { | |
912 | require = needed; | |
913 | last_sbrk_top = 0; | |
914 | sbrked_remains = 0; | |
915 | } | |
916 | ||
917 | DEBUG_m(PerlIO_printf(Perl_debug_log, | |
918 | "sbrk(%ld) for %ld-byte-long arena\n", | |
919 | (long)require, (long) needed)); | |
920 | cp = (char *)sbrk(require); | |
921 | #ifdef DEBUGGING_MSTATS | |
922 | sbrks++; | |
923 | #endif | |
924 | if (cp == last_sbrk_top) { | |
925 | /* Common case, anything is fine. */ | |
926 | sbrk_good++; | |
927 | ovp = (union overhead *) (cp - sbrked_remains); | |
928 | sbrked_remains = require - (needed - sbrked_remains); | |
929 | } else if (cp == (char *)-1) { /* no more room! */ | |
930 | ovp = (union overhead *)emergency_sbrk(needed); | |
931 | if (ovp == (union overhead *)-1) | |
932 | return 0; | |
933 | return ovp; | |
934 | } else { /* Non-continuous or first sbrk(). */ | |
935 | long add = sbrked_remains; | |
936 | char *newcp; | |
937 | ||
938 | if (sbrked_remains) { /* Put rest into chain, we | |
939 | cannot use it right now. */ | |
940 | add_to_chain((void*)(last_sbrk_top - sbrked_remains), | |
941 | sbrked_remains, 0); | |
942 | } | |
943 | ||
944 | /* Second, check alignment. */ | |
945 | slack = 0; | |
946 | ||
947 | #ifndef atarist /* on the atari we dont have to worry about this */ | |
948 | # ifndef I286 /* The sbrk(0) call on the I286 always returns the next segment */ | |
949 | ||
950 | /* CHUNK_SHIFT is 1 for PACK_MALLOC, 0 otherwise. */ | |
951 | if ((UV)cp & (0x7FF >> CHUNK_SHIFT)) { /* Not aligned. */ | |
952 | slack = (0x800 >> CHUNK_SHIFT) | |
953 | - ((UV)cp & (0x7FF >> CHUNK_SHIFT)); | |
954 | add += slack; | |
955 | } | |
956 | # endif | |
957 | #endif /* atarist */ | |
958 | ||
959 | if (add) { | |
960 | DEBUG_m(PerlIO_printf(Perl_debug_log, | |
961 | "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", | |
962 | (long)add, (long) slack, | |
963 | (long) sbrked_remains)); | |
964 | newcp = (char *)sbrk(add); | |
965 | #if defined(DEBUGGING_MSTATS) | |
966 | sbrks++; | |
967 | sbrk_slack += add; | |
968 | #endif | |
969 | if (newcp != cp + require) { | |
970 | /* Too bad: even rounding sbrk() is not continuous.*/ | |
971 | DEBUG_m(PerlIO_printf(Perl_debug_log, | |
972 | "failed to fix bad sbrk()\n")); | |
973 | #ifdef PACK_MALLOC | |
974 | if (slack) { | |
51dc0457 | 975 | MUTEX_UNLOCK(&PL_malloc_mutex); |
fa423c5b IZ |
976 | croak("%s", "panic: Off-page sbrk"); |
977 | } | |
978 | #endif | |
979 | if (sbrked_remains) { | |
980 | /* Try again. */ | |
981 | #if defined(DEBUGGING_MSTATS) | |
982 | sbrk_slack += require; | |
983 | #endif | |
984 | require = needed; | |
985 | DEBUG_m(PerlIO_printf(Perl_debug_log, | |
986 | "straight sbrk(%ld)\n", | |
987 | (long)require)); | |
988 | cp = (char *)sbrk(require); | |
989 | #ifdef DEBUGGING_MSTATS | |
990 | sbrks++; | |
991 | #endif | |
992 | if (cp == (char *)-1) | |
993 | return 0; | |
994 | } | |
995 | sbrk_good = -1; /* Disable optimization! | |
996 | Continue with not-aligned... */ | |
997 | } else { | |
998 | cp += slack; | |
999 | require += sbrked_remains; | |
1000 | } | |
1001 | } | |
1002 | ||
1003 | if (last_sbrk_top) { | |
1004 | sbrk_good -= SBRK_FAILURE_PRICE; | |
1005 | } | |
1006 | ||
1007 | ovp = (union overhead *) cp; | |
1008 | /* | |
1009 | * Round up to minimum allocation size boundary | |
1010 | * and deduct from block count to reflect. | |
1011 | */ | |
1012 | ||
1013 | #ifndef I286 /* Again, this should always be ok on an 80286 */ | |
1014 | if ((UV)ovp & 7) { | |
1015 | ovp = (union overhead *)(((UV)ovp + 8) & ~7); | |
1016 | DEBUG_m(PerlIO_printf(Perl_debug_log, | |
1017 | "fixing sbrk(): %d bytes off machine alignement\n", | |
1018 | (int)((UV)ovp & 7))); | |
1019 | (*nblksp)--; | |
1020 | # if defined(DEBUGGING_MSTATS) | |
1021 | /* This is only approx. if TWO_POT_OPTIMIZE: */ | |
1022 | sbrk_slack += (1 << bucket); | |
1023 | # endif | |
1024 | } | |
1025 | #endif | |
1026 | sbrked_remains = require - needed; | |
1027 | } | |
1028 | last_sbrk_top = cp + require; | |
1029 | last_op = (char*) cp; | |
1030 | #ifdef DEBUGGING_MSTATS | |
1031 | goodsbrk += require; | |
1032 | #endif | |
1033 | return ovp; | |
1034 | } | |
1035 | ||
1036 | static int | |
1037 | getpages_adjacent(int require) | |
1038 | { | |
1039 | if (require <= sbrked_remains) { | |
1040 | sbrked_remains -= require; | |
1041 | } else { | |
1042 | char *cp; | |
1043 | ||
1044 | require -= sbrked_remains; | |
1045 | /* We do not try to optimize sbrks here, we go for place. */ | |
1046 | cp = (char*) sbrk(require); | |
1047 | #ifdef DEBUGGING_MSTATS | |
1048 | sbrks++; | |
1049 | goodsbrk += require; | |
1050 | #endif | |
1051 | if (cp == last_sbrk_top) { | |
1052 | sbrked_remains = 0; | |
1053 | last_sbrk_top = cp + require; | |
1054 | } else { | |
28ac10b1 IZ |
1055 | if (cp == (char*)-1) { /* Out of memory */ |
1056 | #ifdef DEBUGGING_MSTATS | |
1057 | goodsbrk -= require; | |
1058 | #endif | |
1059 | return 0; | |
1060 | } | |
fa423c5b IZ |
1061 | /* Report the failure: */ |
1062 | if (sbrked_remains) | |
1063 | add_to_chain((void*)(last_sbrk_top - sbrked_remains), | |
1064 | sbrked_remains, 0); | |
1065 | add_to_chain((void*)cp, require, 0); | |
1066 | sbrk_good -= SBRK_FAILURE_PRICE; | |
1067 | sbrked_remains = 0; | |
1068 | last_sbrk_top = 0; | |
1069 | last_op = 0; | |
1070 | return 0; | |
1071 | } | |
1072 | } | |
1073 | ||
1074 | return 1; | |
1075 | } | |
1076 | ||
8d063cd8 LW |
1077 | /* |
1078 | * Allocate more memory to the indicated bucket. | |
1079 | */ | |
a0d0e21e | 1080 | static void |
8ac85365 | 1081 | morecore(register int bucket) |
8d063cd8 | 1082 | { |
72aaf631 | 1083 | register union overhead *ovp; |
8d063cd8 | 1084 | register int rnu; /* 2^rnu bytes will be requested */ |
fa423c5b | 1085 | int nblks; /* become nblks blocks of the desired size */ |
bbce6d69 | 1086 | register MEM_SIZE siz, needed; |
8d063cd8 LW |
1087 | |
1088 | if (nextf[bucket]) | |
1089 | return; | |
e8bc2b5c | 1090 | if (bucket == sizeof(MEM_SIZE)*8*BUCKETS_PER_POW2) { |
51dc0457 | 1091 | MUTEX_UNLOCK(&PL_malloc_mutex); |
d720c441 | 1092 | croak("%s", "Out of memory during ridiculously large request"); |
55497cff | 1093 | } |
d720c441 | 1094 | if (bucket > max_bucket) |
e8bc2b5c | 1095 | max_bucket = bucket; |
d720c441 | 1096 | |
e8bc2b5c GS |
1097 | rnu = ( (bucket <= (LOG_OF_MIN_ARENA << BUCKET_POW2_SHIFT)) |
1098 | ? LOG_OF_MIN_ARENA | |
1099 | : (bucket >> BUCKET_POW2_SHIFT) ); | |
1100 | /* This may be overwritten later: */ | |
1101 | nblks = 1 << (rnu - (bucket >> BUCKET_POW2_SHIFT)); /* how many blocks to get */ | |
1102 | needed = ((MEM_SIZE)1 << rnu) + POW2_OPTIMIZE_SURPLUS(bucket); | |
1103 | if (nextf[rnu << BUCKET_POW2_SHIFT]) { /* 2048b bucket. */ | |
1104 | ovp = nextf[rnu << BUCKET_POW2_SHIFT] - 1 + CHUNK_SHIFT; | |
1105 | nextf[rnu << BUCKET_POW2_SHIFT] | |
1106 | = nextf[rnu << BUCKET_POW2_SHIFT]->ov_next; | |
1107 | #ifdef DEBUGGING_MSTATS | |
1108 | nmalloc[rnu << BUCKET_POW2_SHIFT]--; | |
1109 | start_slack -= M_OVERHEAD; | |
1110 | #endif | |
1111 | DEBUG_m(PerlIO_printf(Perl_debug_log, | |
1112 | "stealing %ld bytes from %ld arena\n", | |
1113 | (long) needed, (long) rnu << BUCKET_POW2_SHIFT)); | |
1114 | } else if (chunk_chain | |
1115 | && (ovp = (union overhead*) get_from_chain(needed))) { | |
1116 | DEBUG_m(PerlIO_printf(Perl_debug_log, | |
1117 | "stealing %ld bytes from chain\n", | |
1118 | (long) needed)); | |
d720c441 IZ |
1119 | } else if ( (ovp = (union overhead*) |
1120 | get_from_bigger_buckets((rnu << BUCKET_POW2_SHIFT) + 1, | |
1121 | needed)) ) { | |
e8bc2b5c GS |
1122 | DEBUG_m(PerlIO_printf(Perl_debug_log, |
1123 | "stealing %ld bytes from bigger buckets\n", | |
1124 | (long) needed)); | |
1125 | } else if (needed <= sbrked_remains) { | |
1126 | ovp = (union overhead *)(last_sbrk_top - sbrked_remains); | |
1127 | sbrked_remains -= needed; | |
1128 | last_op = (char*)ovp; | |
fa423c5b IZ |
1129 | } else |
1130 | ovp = getpages(needed, &nblks, bucket); | |
e8bc2b5c | 1131 | |
fa423c5b IZ |
1132 | if (!ovp) |
1133 | return; | |
e8bc2b5c | 1134 | |
8d063cd8 LW |
1135 | /* |
1136 | * Add new memory allocated to that on | |
1137 | * free list for this hash bucket. | |
1138 | */ | |
e8bc2b5c | 1139 | siz = BUCKET_SIZE(bucket); |
cf5c4ad8 | 1140 | #ifdef PACK_MALLOC |
72aaf631 | 1141 | *(u_char*)ovp = bucket; /* Fill index. */ |
e8bc2b5c GS |
1142 | if (bucket <= MAX_PACKED) { |
1143 | ovp = (union overhead *) ((char*)ovp + BLK_SHIFT(bucket)); | |
1144 | nblks = N_BLKS(bucket); | |
cf5c4ad8 | 1145 | # ifdef DEBUGGING_MSTATS |
e8bc2b5c | 1146 | start_slack += BLK_SHIFT(bucket); |
cf5c4ad8 | 1147 | # endif |
e8bc2b5c GS |
1148 | } else if (bucket < LOG_OF_MIN_ARENA * BUCKETS_PER_POW2) { |
1149 | ovp = (union overhead *) ((char*)ovp + BLK_SHIFT(bucket)); | |
cf5c4ad8 | 1150 | siz -= sizeof(union overhead); |
72aaf631 | 1151 | } else ovp++; /* One chunk per block. */ |
e8bc2b5c | 1152 | #endif /* PACK_MALLOC */ |
72aaf631 | 1153 | nextf[bucket] = ovp; |
5f05dabc | 1154 | #ifdef DEBUGGING_MSTATS |
1155 | nmalloc[bucket] += nblks; | |
e8bc2b5c GS |
1156 | if (bucket > MAX_PACKED) { |
1157 | start_slack += M_OVERHEAD * nblks; | |
1158 | } | |
5f05dabc | 1159 | #endif |
8d063cd8 | 1160 | while (--nblks > 0) { |
72aaf631 MB |
1161 | ovp->ov_next = (union overhead *)((caddr_t)ovp + siz); |
1162 | ovp = (union overhead *)((caddr_t)ovp + siz); | |
8d063cd8 | 1163 | } |
8595d6f1 | 1164 | /* Not all sbrks return zeroed memory.*/ |
72aaf631 | 1165 | ovp->ov_next = (union overhead *)NULL; |
cf5c4ad8 | 1166 | #ifdef PACK_MALLOC |
e8bc2b5c GS |
1167 | if (bucket == 7*BUCKETS_PER_POW2) { /* Special case, explanation is above. */ |
1168 | union overhead *n_op = nextf[7*BUCKETS_PER_POW2]->ov_next; | |
1169 | nextf[7*BUCKETS_PER_POW2] = | |
1170 | (union overhead *)((caddr_t)nextf[7*BUCKETS_PER_POW2] | |
1171 | - sizeof(union overhead)); | |
1172 | nextf[7*BUCKETS_PER_POW2]->ov_next = n_op; | |
cf5c4ad8 | 1173 | } |
1174 | #endif /* !PACK_MALLOC */ | |
8d063cd8 LW |
1175 | } |
1176 | ||
94b6baf5 | 1177 | Free_t |
8ac85365 | 1178 | free(void *mp) |
8d063cd8 | 1179 | { |
ee0007ab | 1180 | register MEM_SIZE size; |
72aaf631 | 1181 | register union overhead *ovp; |
352d5a3a | 1182 | char *cp = (char*)mp; |
cf5c4ad8 | 1183 | #ifdef PACK_MALLOC |
1184 | u_char bucket; | |
1185 | #endif | |
8d063cd8 | 1186 | |
e8bc2b5c GS |
1187 | DEBUG_m(PerlIO_printf(Perl_debug_log, |
1188 | "0x%lx: (%05lu) free\n", | |
4a33f861 | 1189 | (unsigned long)cp, (unsigned long)(PL_an++))); |
45d8adaa | 1190 | |
cf5c4ad8 | 1191 | if (cp == NULL) |
1192 | return; | |
72aaf631 | 1193 | ovp = (union overhead *)((caddr_t)cp |
e8bc2b5c | 1194 | - sizeof (union overhead) * CHUNK_SHIFT); |
cf5c4ad8 | 1195 | #ifdef PACK_MALLOC |
72aaf631 | 1196 | bucket = OV_INDEX(ovp); |
cf5c4ad8 | 1197 | #endif |
e8bc2b5c GS |
1198 | #ifdef IGNORE_SMALL_BAD_FREE |
1199 | if ((bucket >= FIRST_BUCKET_WITH_CHECK) | |
1200 | && (OV_MAGIC(ovp, bucket) != MAGIC)) | |
1201 | #else | |
1202 | if (OV_MAGIC(ovp, bucket) != MAGIC) | |
1203 | #endif | |
1204 | { | |
68dc0745 | 1205 | static int bad_free_warn = -1; |
cf5c4ad8 | 1206 | if (bad_free_warn == -1) { |
5fd9e9a4 | 1207 | char *pbf = PerlEnv_getenv("PERL_BADFREE"); |
cf5c4ad8 | 1208 | bad_free_warn = (pbf) ? atoi(pbf) : 1; |
1209 | } | |
1210 | if (!bad_free_warn) | |
1211 | return; | |
8990e307 | 1212 | #ifdef RCHECK |
a687059c | 1213 | warn("%s free() ignored", |
72aaf631 | 1214 | ovp->ov_rmagic == RMAGIC - 1 ? "Duplicate" : "Bad"); |
8990e307 | 1215 | #else |
d720c441 | 1216 | warn("%s", "Bad free() ignored"); |
8990e307 | 1217 | #endif |
8d063cd8 | 1218 | return; /* sanity */ |
e8bc2b5c | 1219 | } |
51dc0457 | 1220 | MUTEX_LOCK(&PL_malloc_mutex); |
8d063cd8 | 1221 | #ifdef RCHECK |
d720c441 | 1222 | ASSERT(ovp->ov_rmagic == RMAGIC, "chunk's head overwrite"); |
e8bc2b5c GS |
1223 | if (OV_INDEX(ovp) <= MAX_SHORT_BUCKET) { |
1224 | int i; | |
1225 | MEM_SIZE nbytes = ovp->ov_size + 1; | |
1226 | ||
1227 | if ((i = nbytes & 3)) { | |
1228 | i = 4 - i; | |
1229 | while (i--) { | |
1230 | ASSERT(*((char *)((caddr_t)ovp + nbytes - RSLOP + i)) | |
d720c441 | 1231 | == RMAGIC_C, "chunk's tail overwrite"); |
e8bc2b5c GS |
1232 | } |
1233 | } | |
1234 | nbytes = (nbytes + 3) &~ 3; | |
d720c441 | 1235 | ASSERT(*(u_int *)((caddr_t)ovp + nbytes - RSLOP) == RMAGIC, "chunk's tail overwrite"); |
e8bc2b5c | 1236 | } |
72aaf631 | 1237 | ovp->ov_rmagic = RMAGIC - 1; |
8d063cd8 | 1238 | #endif |
d720c441 | 1239 | ASSERT(OV_INDEX(ovp) < NBUCKETS, "chunk's head overwrite"); |
72aaf631 MB |
1240 | size = OV_INDEX(ovp); |
1241 | ovp->ov_next = nextf[size]; | |
1242 | nextf[size] = ovp; | |
51dc0457 | 1243 | MUTEX_UNLOCK(&PL_malloc_mutex); |
8d063cd8 LW |
1244 | } |
1245 | ||
1246 | /* | |
1247 | * When a program attempts "storage compaction" as mentioned in the | |
1248 | * old malloc man page, it realloc's an already freed block. Usually | |
1249 | * this is the last block it freed; occasionally it might be farther | |
1250 | * back. We have to search all the free lists for the block in order | |
1251 | * to determine its bucket: 1st we make one pass thru the lists | |
1252 | * checking only the first block in each; if that fails we search | |
378cc40b | 1253 | * ``reall_srchlen'' blocks in each list for a match (the variable |
8d063cd8 LW |
1254 | * is extern so the caller can modify it). If that fails we just copy |
1255 | * however many bytes was given to realloc() and hope it's not huge. | |
1256 | */ | |
378cc40b | 1257 | int reall_srchlen = 4; /* 4 should be plenty, -1 =>'s whole list */ |
8d063cd8 | 1258 | |
2304df62 | 1259 | Malloc_t |
8ac85365 | 1260 | realloc(void *mp, size_t nbytes) |
8d063cd8 | 1261 | { |
ee0007ab | 1262 | register MEM_SIZE onb; |
72aaf631 | 1263 | union overhead *ovp; |
d720c441 IZ |
1264 | char *res; |
1265 | int prev_bucket; | |
e8bc2b5c GS |
1266 | register int bucket; |
1267 | int was_alloced = 0, incr; | |
352d5a3a | 1268 | char *cp = (char*)mp; |
8d063cd8 | 1269 | |
e8bc2b5c | 1270 | #if defined(DEBUGGING) || !defined(PERL_CORE) |
ee0007ab | 1271 | MEM_SIZE size = nbytes; |
45d8adaa | 1272 | |
45d8adaa | 1273 | if ((long)nbytes < 0) |
d720c441 | 1274 | croak("%s", "panic: realloc"); |
45d8adaa | 1275 | #endif |
e8bc2b5c GS |
1276 | |
1277 | BARK_64K_LIMIT("Reallocation",nbytes,size); | |
1278 | if (!cp) | |
1279 | return malloc(nbytes); | |
45d8adaa | 1280 | |
51dc0457 | 1281 | MUTEX_LOCK(&PL_malloc_mutex); |
72aaf631 | 1282 | ovp = (union overhead *)((caddr_t)cp |
e8bc2b5c GS |
1283 | - sizeof (union overhead) * CHUNK_SHIFT); |
1284 | bucket = OV_INDEX(ovp); | |
1285 | #ifdef IGNORE_SMALL_BAD_FREE | |
1286 | if ((bucket < FIRST_BUCKET_WITH_CHECK) | |
1287 | || (OV_MAGIC(ovp, bucket) == MAGIC)) | |
1288 | #else | |
1289 | if (OV_MAGIC(ovp, bucket) == MAGIC) | |
1290 | #endif | |
1291 | { | |
55497cff | 1292 | was_alloced = 1; |
8d063cd8 LW |
1293 | } else { |
1294 | /* | |
1295 | * Already free, doing "compaction". | |
1296 | * | |
1297 | * Search for the old block of memory on the | |
1298 | * free list. First, check the most common | |
1299 | * case (last element free'd), then (this failing) | |
378cc40b | 1300 | * the last ``reall_srchlen'' items free'd. |
8d063cd8 LW |
1301 | * If all lookups fail, then assume the size of |
1302 | * the memory block being realloc'd is the | |
1303 | * smallest possible. | |
1304 | */ | |
e8bc2b5c GS |
1305 | if ((bucket = findbucket(ovp, 1)) < 0 && |
1306 | (bucket = findbucket(ovp, reall_srchlen)) < 0) | |
1307 | bucket = 0; | |
8d063cd8 | 1308 | } |
e8bc2b5c | 1309 | onb = BUCKET_SIZE_REAL(bucket); |
55497cff | 1310 | /* |
1311 | * avoid the copy if same size block. | |
e8bc2b5c GS |
1312 | * We are not agressive with boundary cases. Note that it might |
1313 | * (for a small number of cases) give false negative if | |
55497cff | 1314 | * both new size and old one are in the bucket for |
e8bc2b5c GS |
1315 | * FIRST_BIG_POW2, but the new one is near the lower end. |
1316 | * | |
1317 | * We do not try to go to 1.5 times smaller bucket so far. | |
55497cff | 1318 | */ |
e8bc2b5c GS |
1319 | if (nbytes > onb) incr = 1; |
1320 | else { | |
1321 | #ifdef DO_NOT_TRY_HARDER_WHEN_SHRINKING | |
1322 | if ( /* This is a little bit pessimal if PACK_MALLOC: */ | |
1323 | nbytes > ( (onb >> 1) - M_OVERHEAD ) | |
1324 | # ifdef TWO_POT_OPTIMIZE | |
1325 | || (bucket == FIRST_BIG_POW2 && nbytes >= LAST_SMALL_BOUND ) | |
1326 | # endif | |
1327 | ) | |
1328 | #else /* !DO_NOT_TRY_HARDER_WHEN_SHRINKING */ | |
1329 | prev_bucket = ( (bucket > MAX_PACKED + 1) | |
1330 | ? bucket - BUCKETS_PER_POW2 | |
1331 | : bucket - 1); | |
1332 | if (nbytes > BUCKET_SIZE_REAL(prev_bucket)) | |
1333 | #endif /* !DO_NOT_TRY_HARDER_WHEN_SHRINKING */ | |
1334 | incr = 0; | |
1335 | else incr = -1; | |
1336 | } | |
1337 | if (!was_alloced | |
2ce36478 | 1338 | #ifdef STRESS_REALLOC |
e8bc2b5c | 1339 | || 1 /* always do it the hard way */ |
2ce36478 | 1340 | #endif |
e8bc2b5c GS |
1341 | ) goto hard_way; |
1342 | else if (incr == 0) { | |
852c2e52 | 1343 | inplace_label: |
a687059c LW |
1344 | #ifdef RCHECK |
1345 | /* | |
1346 | * Record new allocated size of block and | |
1347 | * bound space with magic numbers. | |
1348 | */ | |
72aaf631 | 1349 | if (OV_INDEX(ovp) <= MAX_SHORT_BUCKET) { |
e8bc2b5c GS |
1350 | int i, nb = ovp->ov_size + 1; |
1351 | ||
1352 | if ((i = nb & 3)) { | |
1353 | i = 4 - i; | |
1354 | while (i--) { | |
d720c441 | 1355 | ASSERT(*((char *)((caddr_t)ovp + nb - RSLOP + i)) == RMAGIC_C, "chunk's tail overwrite"); |
e8bc2b5c GS |
1356 | } |
1357 | } | |
1358 | nb = (nb + 3) &~ 3; | |
d720c441 | 1359 | ASSERT(*(u_int *)((caddr_t)ovp + nb - RSLOP) == RMAGIC, "chunk's tail overwrite"); |
a687059c LW |
1360 | /* |
1361 | * Convert amount of memory requested into | |
1362 | * closest block size stored in hash buckets | |
1363 | * which satisfies request. Account for | |
1364 | * space used per block for accounting. | |
1365 | */ | |
cf5c4ad8 | 1366 | nbytes += M_OVERHEAD; |
72aaf631 | 1367 | ovp->ov_size = nbytes - 1; |
e8bc2b5c GS |
1368 | if ((i = nbytes & 3)) { |
1369 | i = 4 - i; | |
1370 | while (i--) | |
1371 | *((char *)((caddr_t)ovp + nbytes - RSLOP + i)) | |
1372 | = RMAGIC_C; | |
1373 | } | |
1374 | nbytes = (nbytes + 3) &~ 3; | |
72aaf631 | 1375 | *((u_int *)((caddr_t)ovp + nbytes - RSLOP)) = RMAGIC; |
a687059c LW |
1376 | } |
1377 | #endif | |
45d8adaa | 1378 | res = cp; |
51dc0457 | 1379 | MUTEX_UNLOCK(&PL_malloc_mutex); |
42ac124e IZ |
1380 | DEBUG_m(PerlIO_printf(Perl_debug_log, |
1381 | "0x%lx: (%05lu) realloc %ld bytes inplace\n", | |
1382 | (unsigned long)res,(unsigned long)(PL_an++), | |
1383 | (long)size)); | |
e8bc2b5c GS |
1384 | } else if (incr == 1 && (cp - M_OVERHEAD == last_op) |
1385 | && (onb > (1 << LOG_OF_MIN_ARENA))) { | |
1386 | MEM_SIZE require, newarena = nbytes, pow; | |
1387 | int shiftr; | |
1388 | ||
1389 | POW2_OPTIMIZE_ADJUST(newarena); | |
1390 | newarena = newarena + M_OVERHEAD; | |
1391 | /* newarena = (newarena + 3) &~ 3; */ | |
1392 | shiftr = (newarena - 1) >> LOG_OF_MIN_ARENA; | |
1393 | pow = LOG_OF_MIN_ARENA + 1; | |
1394 | /* apart from this loop, this is O(1) */ | |
1395 | while (shiftr >>= 1) | |
1396 | pow++; | |
1397 | newarena = (1 << pow) + POW2_OPTIMIZE_SURPLUS(pow * BUCKETS_PER_POW2); | |
1398 | require = newarena - onb - M_OVERHEAD; | |
1399 | ||
fa423c5b | 1400 | if (getpages_adjacent(require)) { |
e8bc2b5c | 1401 | #ifdef DEBUGGING_MSTATS |
fa423c5b IZ |
1402 | nmalloc[bucket]--; |
1403 | nmalloc[pow * BUCKETS_PER_POW2]++; | |
e8bc2b5c | 1404 | #endif |
fa423c5b IZ |
1405 | *(cp - M_OVERHEAD) = pow * BUCKETS_PER_POW2; /* Fill index. */ |
1406 | goto inplace_label; | |
1407 | } else | |
1408 | goto hard_way; | |
e8bc2b5c GS |
1409 | } else { |
1410 | hard_way: | |
51dc0457 | 1411 | MUTEX_UNLOCK(&PL_malloc_mutex); |
42ac124e IZ |
1412 | DEBUG_m(PerlIO_printf(Perl_debug_log, |
1413 | "0x%lx: (%05lu) realloc %ld bytes the hard way\n", | |
1414 | (unsigned long)cp,(unsigned long)(PL_an++), | |
1415 | (long)size)); | |
e8bc2b5c GS |
1416 | if ((res = (char*)malloc(nbytes)) == NULL) |
1417 | return (NULL); | |
1418 | if (cp != res) /* common optimization */ | |
1419 | Copy(cp, res, (MEM_SIZE)(nbytes<onb?nbytes:onb), char); | |
1420 | if (was_alloced) | |
1421 | free(cp); | |
45d8adaa | 1422 | } |
2304df62 | 1423 | return ((Malloc_t)res); |
8d063cd8 LW |
1424 | } |
1425 | ||
1426 | /* | |
1427 | * Search ``srchlen'' elements of each free list for a block whose | |
1428 | * header starts at ``freep''. If srchlen is -1 search the whole list. | |
1429 | * Return bucket number, or -1 if not found. | |
1430 | */ | |
ee0007ab | 1431 | static int |
8ac85365 | 1432 | findbucket(union overhead *freep, int srchlen) |
8d063cd8 LW |
1433 | { |
1434 | register union overhead *p; | |
1435 | register int i, j; | |
1436 | ||
1437 | for (i = 0; i < NBUCKETS; i++) { | |
1438 | j = 0; | |
1439 | for (p = nextf[i]; p && j != srchlen; p = p->ov_next) { | |
1440 | if (p == freep) | |
1441 | return (i); | |
1442 | j++; | |
1443 | } | |
1444 | } | |
1445 | return (-1); | |
1446 | } | |
1447 | ||
cf5c4ad8 | 1448 | Malloc_t |
8ac85365 | 1449 | calloc(register size_t elements, register size_t size) |
cf5c4ad8 | 1450 | { |
1451 | long sz = elements * size; | |
1452 | Malloc_t p = malloc(sz); | |
1453 | ||
1454 | if (p) { | |
1455 | memset((void*)p, 0, sz); | |
1456 | } | |
1457 | return p; | |
1458 | } | |
1459 | ||
e8bc2b5c GS |
1460 | MEM_SIZE |
1461 | malloced_size(void *p) | |
1462 | { | |
8d6dde3e IZ |
1463 | union overhead *ovp = (union overhead *) |
1464 | ((caddr_t)p - sizeof (union overhead) * CHUNK_SHIFT); | |
1465 | int bucket = OV_INDEX(ovp); | |
1466 | #ifdef RCHECK | |
1467 | /* The caller wants to have a complete control over the chunk, | |
1468 | disable the memory checking inside the chunk. */ | |
1469 | if (bucket <= MAX_SHORT_BUCKET) { | |
1470 | MEM_SIZE size = BUCKET_SIZE_REAL(bucket); | |
1471 | ovp->ov_size = size + M_OVERHEAD - 1; | |
1472 | *((u_int *)((caddr_t)ovp + size + M_OVERHEAD - RSLOP)) = RMAGIC; | |
1473 | } | |
1474 | #endif | |
e8bc2b5c GS |
1475 | return BUCKET_SIZE_REAL(bucket); |
1476 | } | |
1477 | ||
c07a80fd | 1478 | #ifdef DEBUGGING_MSTATS |
e8bc2b5c GS |
1479 | |
1480 | # ifdef BUCKETS_ROOT2 | |
1481 | # define MIN_EVEN_REPORT 6 | |
1482 | # else | |
1483 | # define MIN_EVEN_REPORT MIN_BUCKET | |
1484 | # endif | |
8d063cd8 LW |
1485 | /* |
1486 | * mstats - print out statistics about malloc | |
1487 | * | |
1488 | * Prints two lines of numbers, one showing the length of the free list | |
1489 | * for each size category, the second showing the number of mallocs - | |
1490 | * frees for each size category. | |
1491 | */ | |
ee0007ab | 1492 | void |
8ac85365 | 1493 | dump_mstats(char *s) |
8d063cd8 LW |
1494 | { |
1495 | register int i, j; | |
1496 | register union overhead *p; | |
e8bc2b5c | 1497 | int topbucket=0, topbucket_ev=0, topbucket_odd=0, totfree=0, total=0; |
c07a80fd | 1498 | u_int nfree[NBUCKETS]; |
e8bc2b5c GS |
1499 | int total_chain = 0; |
1500 | struct chunk_chain_s* nextchain = chunk_chain; | |
8d063cd8 | 1501 | |
e8bc2b5c | 1502 | for (i = MIN_BUCKET ; i < NBUCKETS; i++) { |
8d063cd8 LW |
1503 | for (j = 0, p = nextf[i]; p; p = p->ov_next, j++) |
1504 | ; | |
c07a80fd | 1505 | nfree[i] = j; |
e8bc2b5c GS |
1506 | totfree += nfree[i] * BUCKET_SIZE_REAL(i); |
1507 | total += nmalloc[i] * BUCKET_SIZE_REAL(i); | |
1508 | if (nmalloc[i]) { | |
1509 | i % 2 ? (topbucket_odd = i) : (topbucket_ev = i); | |
1510 | topbucket = i; | |
1511 | } | |
c07a80fd | 1512 | } |
1513 | if (s) | |
e8bc2b5c | 1514 | PerlIO_printf(PerlIO_stderr(), |
d720c441 | 1515 | "Memory allocation statistics %s (buckets %ld(%ld)..%ld(%ld)\n", |
e8bc2b5c | 1516 | s, |
d720c441 IZ |
1517 | (long)BUCKET_SIZE_REAL(MIN_BUCKET), |
1518 | (long)BUCKET_SIZE(MIN_BUCKET), | |
1519 | (long)BUCKET_SIZE_REAL(topbucket), (long)BUCKET_SIZE(topbucket)); | |
5f05dabc | 1520 | PerlIO_printf(PerlIO_stderr(), "%8d free:", totfree); |
e8bc2b5c GS |
1521 | for (i = MIN_EVEN_REPORT; i <= topbucket; i += BUCKETS_PER_POW2) { |
1522 | PerlIO_printf(PerlIO_stderr(), | |
1523 | ((i < 8*BUCKETS_PER_POW2 || i == 10*BUCKETS_PER_POW2) | |
1524 | ? " %5d" | |
1525 | : ((i < 12*BUCKETS_PER_POW2) ? " %3d" : " %d")), | |
1526 | nfree[i]); | |
1527 | } | |
1528 | #ifdef BUCKETS_ROOT2 | |
1529 | PerlIO_printf(PerlIO_stderr(), "\n\t "); | |
1530 | for (i = MIN_BUCKET + 1; i <= topbucket_odd; i += BUCKETS_PER_POW2) { | |
1531 | PerlIO_printf(PerlIO_stderr(), | |
1532 | ((i < 8*BUCKETS_PER_POW2 || i == 10*BUCKETS_PER_POW2) | |
1533 | ? " %5d" | |
1534 | : ((i < 12*BUCKETS_PER_POW2) ? " %3d" : " %d")), | |
1535 | nfree[i]); | |
8d063cd8 | 1536 | } |
e8bc2b5c | 1537 | #endif |
5f05dabc | 1538 | PerlIO_printf(PerlIO_stderr(), "\n%8d used:", total - totfree); |
e8bc2b5c GS |
1539 | for (i = MIN_EVEN_REPORT; i <= topbucket; i += BUCKETS_PER_POW2) { |
1540 | PerlIO_printf(PerlIO_stderr(), | |
1541 | ((i < 8*BUCKETS_PER_POW2 || i == 10*BUCKETS_PER_POW2) | |
1542 | ? " %5d" | |
1543 | : ((i < 12*BUCKETS_PER_POW2) ? " %3d" : " %d")), | |
1544 | nmalloc[i] - nfree[i]); | |
c07a80fd | 1545 | } |
e8bc2b5c GS |
1546 | #ifdef BUCKETS_ROOT2 |
1547 | PerlIO_printf(PerlIO_stderr(), "\n\t "); | |
1548 | for (i = MIN_BUCKET + 1; i <= topbucket_odd; i += BUCKETS_PER_POW2) { | |
1549 | PerlIO_printf(PerlIO_stderr(), | |
1550 | ((i < 8*BUCKETS_PER_POW2 || i == 10*BUCKETS_PER_POW2) | |
1551 | ? " %5d" | |
1552 | : ((i < 12*BUCKETS_PER_POW2) ? " %3d" : " %d")), | |
1553 | nmalloc[i] - nfree[i]); | |
1554 | } | |
1555 | #endif | |
1556 | while (nextchain) { | |
1557 | total_chain += nextchain->size; | |
1558 | nextchain = nextchain->next; | |
1559 | } | |
1560 | PerlIO_printf(PerlIO_stderr(), "\nTotal sbrk(): %d/%d:%d. Odd ends: pad+heads+chain+tail: %d+%d+%d+%d.\n", | |
1561 | goodsbrk + sbrk_slack, sbrks, sbrk_good, sbrk_slack, | |
1562 | start_slack, total_chain, sbrked_remains); | |
c07a80fd | 1563 | } |
1564 | #else | |
1565 | void | |
8ac85365 | 1566 | dump_mstats(char *s) |
c07a80fd | 1567 | { |
8d063cd8 LW |
1568 | } |
1569 | #endif | |
a687059c | 1570 | #endif /* lint */ |
cf5c4ad8 | 1571 | |
1572 | ||
1573 | #ifdef USE_PERL_SBRK | |
1574 | ||
760ac839 LW |
1575 | # ifdef NeXT |
1576 | # define PERL_SBRK_VIA_MALLOC | |
1577 | # endif | |
1578 | ||
38ac2dc8 DD |
1579 | # ifdef __MACHTEN_PPC__ |
1580 | # define PERL_SBRK_VIA_MALLOC | |
1581 | /* | |
1582 | * MachTen's malloc() returns a buffer aligned on a two-byte boundary. | |
1583 | * While this is adequate, it may slow down access to longer data | |
1584 | * types by forcing multiple memory accesses. It also causes | |
1585 | * complaints when RCHECK is in force. So we allocate six bytes | |
1586 | * more than we need to, and return an address rounded up to an | |
1587 | * eight-byte boundary. | |
1588 | * | |
1589 | * 980701 Dominic Dunlop <domo@computer.org> | |
1590 | */ | |
1591 | # define SYSTEM_ALLOC(a) ((void *)(((unsigned)malloc((a)+6)+6)&~7)) | |
1592 | # endif | |
1593 | ||
760ac839 | 1594 | # ifdef PERL_SBRK_VIA_MALLOC |
72e5b9db | 1595 | # if defined(HIDEMYMALLOC) || defined(EMBEDMYMALLOC) |
38ac2dc8 DD |
1596 | # undef malloc /* Expose names that */ |
1597 | # undef calloc /* HIDEMYMALLOC hides */ | |
1598 | # undef realloc | |
1599 | # undef free | |
760ac839 | 1600 | # else |
72e5b9db | 1601 | # include "Error: -DPERL_SBRK_VIA_MALLOC needs -D(HIDE|EMBED)MYMALLOC" |
760ac839 | 1602 | # endif |
cf5c4ad8 | 1603 | |
1604 | /* it may seem schizophrenic to use perl's malloc and let it call system */ | |
1605 | /* malloc, the reason for that is only the 3.2 version of the OS that had */ | |
1606 | /* frequent core dumps within nxzonefreenolock. This sbrk routine put an */ | |
1607 | /* end to the cores */ | |
1608 | ||
38ac2dc8 DD |
1609 | # ifndef SYSTEM_ALLOC |
1610 | # define SYSTEM_ALLOC(a) malloc(a) | |
1611 | # endif | |
cf5c4ad8 | 1612 | |
760ac839 | 1613 | # endif /* PERL_SBRK_VIA_MALLOC */ |
cf5c4ad8 | 1614 | |
1615 | static IV Perl_sbrk_oldchunk; | |
1616 | static long Perl_sbrk_oldsize; | |
1617 | ||
760ac839 LW |
1618 | # define PERLSBRK_32_K (1<<15) |
1619 | # define PERLSBRK_64_K (1<<16) | |
cf5c4ad8 | 1620 | |
b63effbb | 1621 | Malloc_t |
cf5c4ad8 | 1622 | Perl_sbrk(size) |
1623 | int size; | |
1624 | { | |
1625 | IV got; | |
1626 | int small, reqsize; | |
1627 | ||
1628 | if (!size) return 0; | |
55497cff | 1629 | #ifdef PERL_CORE |
cf5c4ad8 | 1630 | reqsize = size; /* just for the DEBUG_m statement */ |
1631 | #endif | |
57569e04 HM |
1632 | #ifdef PACK_MALLOC |
1633 | size = (size + 0x7ff) & ~0x7ff; | |
1634 | #endif | |
cf5c4ad8 | 1635 | if (size <= Perl_sbrk_oldsize) { |
1636 | got = Perl_sbrk_oldchunk; | |
1637 | Perl_sbrk_oldchunk += size; | |
1638 | Perl_sbrk_oldsize -= size; | |
1639 | } else { | |
1640 | if (size >= PERLSBRK_32_K) { | |
1641 | small = 0; | |
1642 | } else { | |
cf5c4ad8 | 1643 | size = PERLSBRK_64_K; |
1644 | small = 1; | |
1645 | } | |
1646 | got = (IV)SYSTEM_ALLOC(size); | |
57569e04 HM |
1647 | #ifdef PACK_MALLOC |
1648 | got = (got + 0x7ff) & ~0x7ff; | |
1649 | #endif | |
cf5c4ad8 | 1650 | if (small) { |
1651 | /* Chunk is small, register the rest for future allocs. */ | |
1652 | Perl_sbrk_oldchunk = got + reqsize; | |
1653 | Perl_sbrk_oldsize = size - reqsize; | |
1654 | } | |
1655 | } | |
1656 | ||
fb73857a | 1657 | DEBUG_m(PerlIO_printf(Perl_debug_log, "sbrk malloc size %ld (reqsize %ld), left size %ld, give addr 0x%lx\n", |
cf5c4ad8 | 1658 | size, reqsize, Perl_sbrk_oldsize, got)); |
cf5c4ad8 | 1659 | |
1660 | return (void *)got; | |
1661 | } | |
1662 | ||
1663 | #endif /* ! defined USE_PERL_SBRK */ |