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56137dbc | 1 | /* Malloc implementation for multiple threads without lock contention. |
bfff8b1b | 2 | Copyright (C) 1996-2017 Free Software Foundation, Inc. |
f65fd747 | 3 | This file is part of the GNU C Library. |
fa8d436c UD |
4 | Contributed by Wolfram Gloger <wg@malloc.de> |
5 | and Doug Lea <dl@cs.oswego.edu>, 2001. | |
f65fd747 UD |
6 | |
7 | The GNU C Library is free software; you can redistribute it and/or | |
cc7375ce RM |
8 | modify it under the terms of the GNU Lesser General Public License as |
9 | published by the Free Software Foundation; either version 2.1 of the | |
fa8d436c | 10 | License, or (at your option) any later version. |
f65fd747 UD |
11 | |
12 | The GNU C Library is distributed in the hope that it will be useful, | |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
cc7375ce | 15 | Lesser General Public License for more details. |
f65fd747 | 16 | |
cc7375ce | 17 | You should have received a copy of the GNU Lesser General Public |
59ba27a6 PE |
18 | License along with the GNU C Library; see the file COPYING.LIB. If |
19 | not, see <http://www.gnu.org/licenses/>. */ | |
f65fd747 | 20 | |
fa8d436c UD |
21 | /* |
22 | This is a version (aka ptmalloc2) of malloc/free/realloc written by | |
23 | Doug Lea and adapted to multiple threads/arenas by Wolfram Gloger. | |
24 | ||
bb2ce416 | 25 | There have been substantial changes made after the integration into |
da2d2fb6 UD |
26 | glibc in all parts of the code. Do not look for much commonality |
27 | with the ptmalloc2 version. | |
28 | ||
fa8d436c | 29 | * Version ptmalloc2-20011215 |
fa8d436c UD |
30 | based on: |
31 | VERSION 2.7.0 Sun Mar 11 14:14:06 2001 Doug Lea (dl at gee) | |
f65fd747 | 32 | |
fa8d436c | 33 | * Quickstart |
f65fd747 | 34 | |
fa8d436c UD |
35 | In order to compile this implementation, a Makefile is provided with |
36 | the ptmalloc2 distribution, which has pre-defined targets for some | |
37 | popular systems (e.g. "make posix" for Posix threads). All that is | |
38 | typically required with regard to compiler flags is the selection of | |
39 | the thread package via defining one out of USE_PTHREADS, USE_THR or | |
40 | USE_SPROC. Check the thread-m.h file for what effects this has. | |
41 | Many/most systems will additionally require USE_TSD_DATA_HACK to be | |
42 | defined, so this is the default for "make posix". | |
f65fd747 UD |
43 | |
44 | * Why use this malloc? | |
45 | ||
46 | This is not the fastest, most space-conserving, most portable, or | |
47 | most tunable malloc ever written. However it is among the fastest | |
48 | while also being among the most space-conserving, portable and tunable. | |
49 | Consistent balance across these factors results in a good general-purpose | |
fa8d436c UD |
50 | allocator for malloc-intensive programs. |
51 | ||
52 | The main properties of the algorithms are: | |
53 | * For large (>= 512 bytes) requests, it is a pure best-fit allocator, | |
54 | with ties normally decided via FIFO (i.e. least recently used). | |
55 | * For small (<= 64 bytes by default) requests, it is a caching | |
56 | allocator, that maintains pools of quickly recycled chunks. | |
57 | * In between, and for combinations of large and small requests, it does | |
58 | the best it can trying to meet both goals at once. | |
59 | * For very large requests (>= 128KB by default), it relies on system | |
60 | memory mapping facilities, if supported. | |
61 | ||
62 | For a longer but slightly out of date high-level description, see | |
63 | http://gee.cs.oswego.edu/dl/html/malloc.html | |
64 | ||
65 | You may already by default be using a C library containing a malloc | |
66 | that is based on some version of this malloc (for example in | |
67 | linux). You might still want to use the one in this file in order to | |
68 | customize settings or to avoid overheads associated with library | |
69 | versions. | |
70 | ||
71 | * Contents, described in more detail in "description of public routines" below. | |
72 | ||
73 | Standard (ANSI/SVID/...) functions: | |
74 | malloc(size_t n); | |
75 | calloc(size_t n_elements, size_t element_size); | |
22a89187 UD |
76 | free(void* p); |
77 | realloc(void* p, size_t n); | |
fa8d436c UD |
78 | memalign(size_t alignment, size_t n); |
79 | valloc(size_t n); | |
80 | mallinfo() | |
81 | mallopt(int parameter_number, int parameter_value) | |
82 | ||
83 | Additional functions: | |
22a89187 UD |
84 | independent_calloc(size_t n_elements, size_t size, void* chunks[]); |
85 | independent_comalloc(size_t n_elements, size_t sizes[], void* chunks[]); | |
fa8d436c | 86 | pvalloc(size_t n); |
fa8d436c | 87 | malloc_trim(size_t pad); |
22a89187 | 88 | malloc_usable_size(void* p); |
fa8d436c | 89 | malloc_stats(); |
f65fd747 UD |
90 | |
91 | * Vital statistics: | |
92 | ||
fa8d436c | 93 | Supported pointer representation: 4 or 8 bytes |
a9177ff5 | 94 | Supported size_t representation: 4 or 8 bytes |
f65fd747 | 95 | Note that size_t is allowed to be 4 bytes even if pointers are 8. |
fa8d436c UD |
96 | You can adjust this by defining INTERNAL_SIZE_T |
97 | ||
98 | Alignment: 2 * sizeof(size_t) (default) | |
99 | (i.e., 8 byte alignment with 4byte size_t). This suffices for | |
100 | nearly all current machines and C compilers. However, you can | |
101 | define MALLOC_ALIGNMENT to be wider than this if necessary. | |
f65fd747 | 102 | |
fa8d436c UD |
103 | Minimum overhead per allocated chunk: 4 or 8 bytes |
104 | Each malloced chunk has a hidden word of overhead holding size | |
f65fd747 UD |
105 | and status information. |
106 | ||
107 | Minimum allocated size: 4-byte ptrs: 16 bytes (including 4 overhead) | |
72f90263 | 108 | 8-byte ptrs: 24/32 bytes (including, 4/8 overhead) |
f65fd747 UD |
109 | |
110 | When a chunk is freed, 12 (for 4byte ptrs) or 20 (for 8 byte | |
111 | ptrs but 4 byte size) or 24 (for 8/8) additional bytes are | |
fa8d436c UD |
112 | needed; 4 (8) for a trailing size field and 8 (16) bytes for |
113 | free list pointers. Thus, the minimum allocatable size is | |
114 | 16/24/32 bytes. | |
f65fd747 UD |
115 | |
116 | Even a request for zero bytes (i.e., malloc(0)) returns a | |
117 | pointer to something of the minimum allocatable size. | |
118 | ||
fa8d436c UD |
119 | The maximum overhead wastage (i.e., number of extra bytes |
120 | allocated than were requested in malloc) is less than or equal | |
121 | to the minimum size, except for requests >= mmap_threshold that | |
122 | are serviced via mmap(), where the worst case wastage is 2 * | |
123 | sizeof(size_t) bytes plus the remainder from a system page (the | |
124 | minimal mmap unit); typically 4096 or 8192 bytes. | |
f65fd747 | 125 | |
a9177ff5 | 126 | Maximum allocated size: 4-byte size_t: 2^32 minus about two pages |
72f90263 | 127 | 8-byte size_t: 2^64 minus about two pages |
fa8d436c UD |
128 | |
129 | It is assumed that (possibly signed) size_t values suffice to | |
f65fd747 UD |
130 | represent chunk sizes. `Possibly signed' is due to the fact |
131 | that `size_t' may be defined on a system as either a signed or | |
fa8d436c UD |
132 | an unsigned type. The ISO C standard says that it must be |
133 | unsigned, but a few systems are known not to adhere to this. | |
134 | Additionally, even when size_t is unsigned, sbrk (which is by | |
135 | default used to obtain memory from system) accepts signed | |
136 | arguments, and may not be able to handle size_t-wide arguments | |
137 | with negative sign bit. Generally, values that would | |
138 | appear as negative after accounting for overhead and alignment | |
139 | are supported only via mmap(), which does not have this | |
140 | limitation. | |
141 | ||
142 | Requests for sizes outside the allowed range will perform an optional | |
143 | failure action and then return null. (Requests may also | |
144 | also fail because a system is out of memory.) | |
145 | ||
22a89187 | 146 | Thread-safety: thread-safe |
fa8d436c UD |
147 | |
148 | Compliance: I believe it is compliant with the 1997 Single Unix Specification | |
2b0fba75 | 149 | Also SVID/XPG, ANSI C, and probably others as well. |
f65fd747 UD |
150 | |
151 | * Synopsis of compile-time options: | |
152 | ||
153 | People have reported using previous versions of this malloc on all | |
154 | versions of Unix, sometimes by tweaking some of the defines | |
22a89187 | 155 | below. It has been tested most extensively on Solaris and Linux. |
fa8d436c UD |
156 | People also report using it in stand-alone embedded systems. |
157 | ||
158 | The implementation is in straight, hand-tuned ANSI C. It is not | |
159 | at all modular. (Sorry!) It uses a lot of macros. To be at all | |
160 | usable, this code should be compiled using an optimizing compiler | |
161 | (for example gcc -O3) that can simplify expressions and control | |
162 | paths. (FAQ: some macros import variables as arguments rather than | |
163 | declare locals because people reported that some debuggers | |
164 | otherwise get confused.) | |
165 | ||
166 | OPTION DEFAULT VALUE | |
167 | ||
168 | Compilation Environment options: | |
169 | ||
2a26ef3a | 170 | HAVE_MREMAP 0 |
fa8d436c UD |
171 | |
172 | Changing default word sizes: | |
173 | ||
174 | INTERNAL_SIZE_T size_t | |
fa8d436c UD |
175 | |
176 | Configuration and functionality options: | |
177 | ||
fa8d436c UD |
178 | USE_PUBLIC_MALLOC_WRAPPERS NOT defined |
179 | USE_MALLOC_LOCK NOT defined | |
180 | MALLOC_DEBUG NOT defined | |
181 | REALLOC_ZERO_BYTES_FREES 1 | |
fa8d436c UD |
182 | TRIM_FASTBINS 0 |
183 | ||
184 | Options for customizing MORECORE: | |
185 | ||
186 | MORECORE sbrk | |
187 | MORECORE_FAILURE -1 | |
a9177ff5 | 188 | MORECORE_CONTIGUOUS 1 |
fa8d436c UD |
189 | MORECORE_CANNOT_TRIM NOT defined |
190 | MORECORE_CLEARS 1 | |
a9177ff5 | 191 | MMAP_AS_MORECORE_SIZE (1024 * 1024) |
fa8d436c UD |
192 | |
193 | Tuning options that are also dynamically changeable via mallopt: | |
194 | ||
425ce2ed | 195 | DEFAULT_MXFAST 64 (for 32bit), 128 (for 64bit) |
fa8d436c UD |
196 | DEFAULT_TRIM_THRESHOLD 128 * 1024 |
197 | DEFAULT_TOP_PAD 0 | |
198 | DEFAULT_MMAP_THRESHOLD 128 * 1024 | |
199 | DEFAULT_MMAP_MAX 65536 | |
200 | ||
201 | There are several other #defined constants and macros that you | |
202 | probably don't want to touch unless you are extending or adapting malloc. */ | |
f65fd747 UD |
203 | |
204 | /* | |
22a89187 | 205 | void* is the pointer type that malloc should say it returns |
f65fd747 UD |
206 | */ |
207 | ||
22a89187 UD |
208 | #ifndef void |
209 | #define void void | |
210 | #endif /*void*/ | |
f65fd747 | 211 | |
fa8d436c UD |
212 | #include <stddef.h> /* for size_t */ |
213 | #include <stdlib.h> /* for getenv(), abort() */ | |
2a26ef3a | 214 | #include <unistd.h> /* for __libc_enable_secure */ |
f65fd747 | 215 | |
425ce2ed | 216 | #include <atomic.h> |
eb96ffb0 | 217 | #include <_itoa.h> |
e404fb16 | 218 | #include <bits/wordsize.h> |
425ce2ed | 219 | #include <sys/sysinfo.h> |
c56da3a3 | 220 | |
02d46fc4 UD |
221 | #include <ldsodefs.h> |
222 | ||
fa8d436c | 223 | #include <unistd.h> |
fa8d436c | 224 | #include <stdio.h> /* needed for malloc_stats */ |
8e58439c | 225 | #include <errno.h> |
f65fd747 | 226 | |
66274218 AJ |
227 | #include <shlib-compat.h> |
228 | ||
5d78bb43 UD |
229 | /* For uintptr_t. */ |
230 | #include <stdint.h> | |
f65fd747 | 231 | |
3e030bd5 UD |
232 | /* For va_arg, va_start, va_end. */ |
233 | #include <stdarg.h> | |
234 | ||
070906ff RM |
235 | /* For MIN, MAX, powerof2. */ |
236 | #include <sys/param.h> | |
237 | ||
ca6be165 | 238 | /* For ALIGN_UP et. al. */ |
9090848d | 239 | #include <libc-pointer-arith.h> |
8a35c3fe | 240 | |
29d79486 | 241 | #include <malloc/malloc-internal.h> |
c0f62c56 | 242 | |
fa8d436c UD |
243 | /* |
244 | Debugging: | |
245 | ||
246 | Because freed chunks may be overwritten with bookkeeping fields, this | |
247 | malloc will often die when freed memory is overwritten by user | |
248 | programs. This can be very effective (albeit in an annoying way) | |
249 | in helping track down dangling pointers. | |
250 | ||
251 | If you compile with -DMALLOC_DEBUG, a number of assertion checks are | |
252 | enabled that will catch more memory errors. You probably won't be | |
253 | able to make much sense of the actual assertion errors, but they | |
254 | should help you locate incorrectly overwritten memory. The checking | |
255 | is fairly extensive, and will slow down execution | |
256 | noticeably. Calling malloc_stats or mallinfo with MALLOC_DEBUG set | |
257 | will attempt to check every non-mmapped allocated and free chunk in | |
258 | the course of computing the summmaries. (By nature, mmapped regions | |
259 | cannot be checked very much automatically.) | |
260 | ||
261 | Setting MALLOC_DEBUG may also be helpful if you are trying to modify | |
262 | this code. The assertions in the check routines spell out in more | |
263 | detail the assumptions and invariants underlying the algorithms. | |
264 | ||
265 | Setting MALLOC_DEBUG does NOT provide an automated mechanism for | |
266 | checking that all accesses to malloced memory stay within their | |
267 | bounds. However, there are several add-ons and adaptations of this | |
268 | or other mallocs available that do this. | |
f65fd747 UD |
269 | */ |
270 | ||
439bda32 WN |
271 | #ifndef MALLOC_DEBUG |
272 | #define MALLOC_DEBUG 0 | |
273 | #endif | |
274 | ||
72f90263 UD |
275 | #ifdef NDEBUG |
276 | # define assert(expr) ((void) 0) | |
277 | #else | |
278 | # define assert(expr) \ | |
279 | ((expr) \ | |
280 | ? ((void) 0) \ | |
8ba14398 | 281 | : __malloc_assert (#expr, __FILE__, __LINE__, __func__)) |
72f90263 UD |
282 | |
283 | extern const char *__progname; | |
284 | ||
285 | static void | |
286 | __malloc_assert (const char *assertion, const char *file, unsigned int line, | |
287 | const char *function) | |
288 | { | |
289 | (void) __fxprintf (NULL, "%s%s%s:%u: %s%sAssertion `%s' failed.\n", | |
290 | __progname, __progname[0] ? ": " : "", | |
291 | file, line, | |
292 | function ? function : "", function ? ": " : "", | |
293 | assertion); | |
294 | fflush (stderr); | |
295 | abort (); | |
296 | } | |
297 | #endif | |
f65fd747 UD |
298 | |
299 | ||
fa8d436c UD |
300 | /* |
301 | REALLOC_ZERO_BYTES_FREES should be set if a call to | |
302 | realloc with zero bytes should be the same as a call to free. | |
303 | This is required by the C standard. Otherwise, since this malloc | |
304 | returns a unique pointer for malloc(0), so does realloc(p, 0). | |
305 | */ | |
306 | ||
307 | #ifndef REALLOC_ZERO_BYTES_FREES | |
308 | #define REALLOC_ZERO_BYTES_FREES 1 | |
309 | #endif | |
310 | ||
311 | /* | |
312 | TRIM_FASTBINS controls whether free() of a very small chunk can | |
313 | immediately lead to trimming. Setting to true (1) can reduce memory | |
314 | footprint, but will almost always slow down programs that use a lot | |
315 | of small chunks. | |
316 | ||
317 | Define this only if you are willing to give up some speed to more | |
318 | aggressively reduce system-level memory footprint when releasing | |
319 | memory in programs that use many small chunks. You can get | |
320 | essentially the same effect by setting MXFAST to 0, but this can | |
321 | lead to even greater slowdowns in programs using many small chunks. | |
322 | TRIM_FASTBINS is an in-between compile-time option, that disables | |
323 | only those chunks bordering topmost memory from being placed in | |
324 | fastbins. | |
325 | */ | |
326 | ||
327 | #ifndef TRIM_FASTBINS | |
328 | #define TRIM_FASTBINS 0 | |
329 | #endif | |
330 | ||
331 | ||
3b49edc0 | 332 | /* Definition for getting more memory from the OS. */ |
fa8d436c UD |
333 | #define MORECORE (*__morecore) |
334 | #define MORECORE_FAILURE 0 | |
22a89187 UD |
335 | void * __default_morecore (ptrdiff_t); |
336 | void *(*__morecore)(ptrdiff_t) = __default_morecore; | |
f65fd747 | 337 | |
f65fd747 | 338 | |
22a89187 | 339 | #include <string.h> |
f65fd747 | 340 | |
fa8d436c UD |
341 | /* |
342 | MORECORE-related declarations. By default, rely on sbrk | |
343 | */ | |
09f5e163 | 344 | |
f65fd747 | 345 | |
fa8d436c UD |
346 | /* |
347 | MORECORE is the name of the routine to call to obtain more memory | |
348 | from the system. See below for general guidance on writing | |
349 | alternative MORECORE functions, as well as a version for WIN32 and a | |
350 | sample version for pre-OSX macos. | |
351 | */ | |
f65fd747 | 352 | |
fa8d436c UD |
353 | #ifndef MORECORE |
354 | #define MORECORE sbrk | |
355 | #endif | |
f65fd747 | 356 | |
fa8d436c UD |
357 | /* |
358 | MORECORE_FAILURE is the value returned upon failure of MORECORE | |
359 | as well as mmap. Since it cannot be an otherwise valid memory address, | |
360 | and must reflect values of standard sys calls, you probably ought not | |
361 | try to redefine it. | |
362 | */ | |
09f5e163 | 363 | |
fa8d436c UD |
364 | #ifndef MORECORE_FAILURE |
365 | #define MORECORE_FAILURE (-1) | |
366 | #endif | |
367 | ||
368 | /* | |
369 | If MORECORE_CONTIGUOUS is true, take advantage of fact that | |
370 | consecutive calls to MORECORE with positive arguments always return | |
371 | contiguous increasing addresses. This is true of unix sbrk. Even | |
372 | if not defined, when regions happen to be contiguous, malloc will | |
373 | permit allocations spanning regions obtained from different | |
374 | calls. But defining this when applicable enables some stronger | |
375 | consistency checks and space efficiencies. | |
376 | */ | |
f65fd747 | 377 | |
fa8d436c UD |
378 | #ifndef MORECORE_CONTIGUOUS |
379 | #define MORECORE_CONTIGUOUS 1 | |
f65fd747 UD |
380 | #endif |
381 | ||
fa8d436c UD |
382 | /* |
383 | Define MORECORE_CANNOT_TRIM if your version of MORECORE | |
384 | cannot release space back to the system when given negative | |
385 | arguments. This is generally necessary only if you are using | |
386 | a hand-crafted MORECORE function that cannot handle negative arguments. | |
387 | */ | |
388 | ||
389 | /* #define MORECORE_CANNOT_TRIM */ | |
f65fd747 | 390 | |
fa8d436c UD |
391 | /* MORECORE_CLEARS (default 1) |
392 | The degree to which the routine mapped to MORECORE zeroes out | |
393 | memory: never (0), only for newly allocated space (1) or always | |
394 | (2). The distinction between (1) and (2) is necessary because on | |
395 | some systems, if the application first decrements and then | |
396 | increments the break value, the contents of the reallocated space | |
397 | are unspecified. | |
6c8dbf00 | 398 | */ |
fa8d436c UD |
399 | |
400 | #ifndef MORECORE_CLEARS | |
6c8dbf00 | 401 | # define MORECORE_CLEARS 1 |
7cabd57c UD |
402 | #endif |
403 | ||
fa8d436c | 404 | |
a9177ff5 | 405 | /* |
fa8d436c | 406 | MMAP_AS_MORECORE_SIZE is the minimum mmap size argument to use if |
22a89187 UD |
407 | sbrk fails, and mmap is used as a backup. The value must be a |
408 | multiple of page size. This backup strategy generally applies only | |
409 | when systems have "holes" in address space, so sbrk cannot perform | |
410 | contiguous expansion, but there is still space available on system. | |
411 | On systems for which this is known to be useful (i.e. most linux | |
412 | kernels), this occurs only when programs allocate huge amounts of | |
413 | memory. Between this, and the fact that mmap regions tend to be | |
414 | limited, the size should be large, to avoid too many mmap calls and | |
415 | thus avoid running out of kernel resources. */ | |
fa8d436c UD |
416 | |
417 | #ifndef MMAP_AS_MORECORE_SIZE | |
418 | #define MMAP_AS_MORECORE_SIZE (1024 * 1024) | |
f65fd747 UD |
419 | #endif |
420 | ||
421 | /* | |
422 | Define HAVE_MREMAP to make realloc() use mremap() to re-allocate | |
2a26ef3a | 423 | large blocks. |
f65fd747 UD |
424 | */ |
425 | ||
426 | #ifndef HAVE_MREMAP | |
fa8d436c | 427 | #define HAVE_MREMAP 0 |
f65fd747 UD |
428 | #endif |
429 | ||
2ba3cfa1 FW |
430 | /* We may need to support __malloc_initialize_hook for backwards |
431 | compatibility. */ | |
432 | ||
433 | #if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_24) | |
434 | # define HAVE_MALLOC_INIT_HOOK 1 | |
435 | #else | |
436 | # define HAVE_MALLOC_INIT_HOOK 0 | |
437 | #endif | |
438 | ||
f65fd747 | 439 | |
f65fd747 | 440 | /* |
f65fd747 | 441 | This version of malloc supports the standard SVID/XPG mallinfo |
fa8d436c UD |
442 | routine that returns a struct containing usage properties and |
443 | statistics. It should work on any SVID/XPG compliant system that has | |
444 | a /usr/include/malloc.h defining struct mallinfo. (If you'd like to | |
445 | install such a thing yourself, cut out the preliminary declarations | |
446 | as described above and below and save them in a malloc.h file. But | |
447 | there's no compelling reason to bother to do this.) | |
f65fd747 UD |
448 | |
449 | The main declaration needed is the mallinfo struct that is returned | |
450 | (by-copy) by mallinfo(). The SVID/XPG malloinfo struct contains a | |
fa8d436c UD |
451 | bunch of fields that are not even meaningful in this version of |
452 | malloc. These fields are are instead filled by mallinfo() with | |
453 | other numbers that might be of interest. | |
f65fd747 UD |
454 | */ |
455 | ||
f65fd747 | 456 | |
fa8d436c | 457 | /* ---------- description of public routines ------------ */ |
f65fd747 UD |
458 | |
459 | /* | |
fa8d436c UD |
460 | malloc(size_t n) |
461 | Returns a pointer to a newly allocated chunk of at least n bytes, or null | |
462 | if no space is available. Additionally, on failure, errno is | |
463 | set to ENOMEM on ANSI C systems. | |
464 | ||
465 | If n is zero, malloc returns a minumum-sized chunk. (The minimum | |
466 | size is 16 bytes on most 32bit systems, and 24 or 32 bytes on 64bit | |
467 | systems.) On most systems, size_t is an unsigned type, so calls | |
468 | with negative arguments are interpreted as requests for huge amounts | |
469 | of space, which will often fail. The maximum supported value of n | |
470 | differs across systems, but is in all cases less than the maximum | |
471 | representable value of a size_t. | |
f65fd747 | 472 | */ |
3b49edc0 UD |
473 | void* __libc_malloc(size_t); |
474 | libc_hidden_proto (__libc_malloc) | |
f65fd747 | 475 | |
fa8d436c | 476 | /* |
22a89187 | 477 | free(void* p) |
fa8d436c UD |
478 | Releases the chunk of memory pointed to by p, that had been previously |
479 | allocated using malloc or a related routine such as realloc. | |
480 | It has no effect if p is null. It can have arbitrary (i.e., bad!) | |
481 | effects if p has already been freed. | |
482 | ||
483 | Unless disabled (using mallopt), freeing very large spaces will | |
484 | when possible, automatically trigger operations that give | |
485 | back unused memory to the system, thus reducing program footprint. | |
486 | */ | |
3b49edc0 UD |
487 | void __libc_free(void*); |
488 | libc_hidden_proto (__libc_free) | |
f65fd747 | 489 | |
fa8d436c UD |
490 | /* |
491 | calloc(size_t n_elements, size_t element_size); | |
492 | Returns a pointer to n_elements * element_size bytes, with all locations | |
493 | set to zero. | |
494 | */ | |
3b49edc0 | 495 | void* __libc_calloc(size_t, size_t); |
f65fd747 UD |
496 | |
497 | /* | |
22a89187 | 498 | realloc(void* p, size_t n) |
fa8d436c UD |
499 | Returns a pointer to a chunk of size n that contains the same data |
500 | as does chunk p up to the minimum of (n, p's size) bytes, or null | |
a9177ff5 | 501 | if no space is available. |
f65fd747 | 502 | |
fa8d436c UD |
503 | The returned pointer may or may not be the same as p. The algorithm |
504 | prefers extending p when possible, otherwise it employs the | |
505 | equivalent of a malloc-copy-free sequence. | |
f65fd747 | 506 | |
a9177ff5 | 507 | If p is null, realloc is equivalent to malloc. |
f65fd747 | 508 | |
fa8d436c UD |
509 | If space is not available, realloc returns null, errno is set (if on |
510 | ANSI) and p is NOT freed. | |
f65fd747 | 511 | |
fa8d436c UD |
512 | if n is for fewer bytes than already held by p, the newly unused |
513 | space is lopped off and freed if possible. Unless the #define | |
514 | REALLOC_ZERO_BYTES_FREES is set, realloc with a size argument of | |
515 | zero (re)allocates a minimum-sized chunk. | |
f65fd747 | 516 | |
3b5f801d DD |
517 | Large chunks that were internally obtained via mmap will always be |
518 | grown using malloc-copy-free sequences unless the system supports | |
519 | MREMAP (currently only linux). | |
f65fd747 | 520 | |
fa8d436c UD |
521 | The old unix realloc convention of allowing the last-free'd chunk |
522 | to be used as an argument to realloc is not supported. | |
f65fd747 | 523 | */ |
3b49edc0 UD |
524 | void* __libc_realloc(void*, size_t); |
525 | libc_hidden_proto (__libc_realloc) | |
f65fd747 | 526 | |
fa8d436c UD |
527 | /* |
528 | memalign(size_t alignment, size_t n); | |
529 | Returns a pointer to a newly allocated chunk of n bytes, aligned | |
530 | in accord with the alignment argument. | |
531 | ||
532 | The alignment argument should be a power of two. If the argument is | |
533 | not a power of two, the nearest greater power is used. | |
534 | 8-byte alignment is guaranteed by normal malloc calls, so don't | |
535 | bother calling memalign with an argument of 8 or less. | |
536 | ||
537 | Overreliance on memalign is a sure way to fragment space. | |
538 | */ | |
3b49edc0 UD |
539 | void* __libc_memalign(size_t, size_t); |
540 | libc_hidden_proto (__libc_memalign) | |
f65fd747 UD |
541 | |
542 | /* | |
fa8d436c UD |
543 | valloc(size_t n); |
544 | Equivalent to memalign(pagesize, n), where pagesize is the page | |
545 | size of the system. If the pagesize is unknown, 4096 is used. | |
546 | */ | |
3b49edc0 | 547 | void* __libc_valloc(size_t); |
fa8d436c | 548 | |
f65fd747 | 549 | |
f65fd747 | 550 | |
fa8d436c UD |
551 | /* |
552 | mallopt(int parameter_number, int parameter_value) | |
553 | Sets tunable parameters The format is to provide a | |
554 | (parameter-number, parameter-value) pair. mallopt then sets the | |
555 | corresponding parameter to the argument value if it can (i.e., so | |
556 | long as the value is meaningful), and returns 1 if successful else | |
557 | 0. SVID/XPG/ANSI defines four standard param numbers for mallopt, | |
558 | normally defined in malloc.h. Only one of these (M_MXFAST) is used | |
559 | in this malloc. The others (M_NLBLKS, M_GRAIN, M_KEEP) don't apply, | |
560 | so setting them has no effect. But this malloc also supports four | |
561 | other options in mallopt. See below for details. Briefly, supported | |
562 | parameters are as follows (listed defaults are for "typical" | |
563 | configurations). | |
564 | ||
565 | Symbol param # default allowed param values | |
566 | M_MXFAST 1 64 0-80 (0 disables fastbins) | |
567 | M_TRIM_THRESHOLD -1 128*1024 any (-1U disables trimming) | |
a9177ff5 | 568 | M_TOP_PAD -2 0 any |
fa8d436c UD |
569 | M_MMAP_THRESHOLD -3 128*1024 any (or 0 if no MMAP support) |
570 | M_MMAP_MAX -4 65536 any (0 disables use of mmap) | |
571 | */ | |
3b49edc0 UD |
572 | int __libc_mallopt(int, int); |
573 | libc_hidden_proto (__libc_mallopt) | |
fa8d436c UD |
574 | |
575 | ||
576 | /* | |
577 | mallinfo() | |
578 | Returns (by copy) a struct containing various summary statistics: | |
579 | ||
a9177ff5 RM |
580 | arena: current total non-mmapped bytes allocated from system |
581 | ordblks: the number of free chunks | |
fa8d436c | 582 | smblks: the number of fastbin blocks (i.e., small chunks that |
72f90263 | 583 | have been freed but not use resused or consolidated) |
a9177ff5 RM |
584 | hblks: current number of mmapped regions |
585 | hblkhd: total bytes held in mmapped regions | |
ca135f82 | 586 | usmblks: always 0 |
a9177ff5 | 587 | fsmblks: total bytes held in fastbin blocks |
fa8d436c | 588 | uordblks: current total allocated space (normal or mmapped) |
a9177ff5 | 589 | fordblks: total free space |
fa8d436c | 590 | keepcost: the maximum number of bytes that could ideally be released |
72f90263 UD |
591 | back to system via malloc_trim. ("ideally" means that |
592 | it ignores page restrictions etc.) | |
fa8d436c UD |
593 | |
594 | Because these fields are ints, but internal bookkeeping may | |
a9177ff5 | 595 | be kept as longs, the reported values may wrap around zero and |
fa8d436c UD |
596 | thus be inaccurate. |
597 | */ | |
3b49edc0 | 598 | struct mallinfo __libc_mallinfo(void); |
88764ae2 | 599 | |
f65fd747 | 600 | |
fa8d436c UD |
601 | /* |
602 | pvalloc(size_t n); | |
603 | Equivalent to valloc(minimum-page-that-holds(n)), that is, | |
604 | round up n to nearest pagesize. | |
605 | */ | |
3b49edc0 | 606 | void* __libc_pvalloc(size_t); |
fa8d436c UD |
607 | |
608 | /* | |
609 | malloc_trim(size_t pad); | |
610 | ||
611 | If possible, gives memory back to the system (via negative | |
612 | arguments to sbrk) if there is unused memory at the `high' end of | |
613 | the malloc pool. You can call this after freeing large blocks of | |
614 | memory to potentially reduce the system-level memory requirements | |
615 | of a program. However, it cannot guarantee to reduce memory. Under | |
616 | some allocation patterns, some large free blocks of memory will be | |
617 | locked between two used chunks, so they cannot be given back to | |
618 | the system. | |
a9177ff5 | 619 | |
fa8d436c UD |
620 | The `pad' argument to malloc_trim represents the amount of free |
621 | trailing space to leave untrimmed. If this argument is zero, | |
622 | only the minimum amount of memory to maintain internal data | |
623 | structures will be left (one page or less). Non-zero arguments | |
624 | can be supplied to maintain enough trailing space to service | |
625 | future expected allocations without having to re-obtain memory | |
626 | from the system. | |
a9177ff5 | 627 | |
fa8d436c UD |
628 | Malloc_trim returns 1 if it actually released any memory, else 0. |
629 | On systems that do not support "negative sbrks", it will always | |
c958a6a4 | 630 | return 0. |
fa8d436c | 631 | */ |
3b49edc0 | 632 | int __malloc_trim(size_t); |
fa8d436c UD |
633 | |
634 | /* | |
22a89187 | 635 | malloc_usable_size(void* p); |
fa8d436c UD |
636 | |
637 | Returns the number of bytes you can actually use in | |
638 | an allocated chunk, which may be more than you requested (although | |
639 | often not) due to alignment and minimum size constraints. | |
640 | You can use this many bytes without worrying about | |
641 | overwriting other allocated objects. This is not a particularly great | |
642 | programming practice. malloc_usable_size can be more useful in | |
643 | debugging and assertions, for example: | |
644 | ||
645 | p = malloc(n); | |
646 | assert(malloc_usable_size(p) >= 256); | |
647 | ||
648 | */ | |
3b49edc0 | 649 | size_t __malloc_usable_size(void*); |
fa8d436c UD |
650 | |
651 | /* | |
652 | malloc_stats(); | |
653 | Prints on stderr the amount of space obtained from the system (both | |
654 | via sbrk and mmap), the maximum amount (which may be more than | |
655 | current if malloc_trim and/or munmap got called), and the current | |
656 | number of bytes allocated via malloc (or realloc, etc) but not yet | |
657 | freed. Note that this is the number of bytes allocated, not the | |
658 | number requested. It will be larger than the number requested | |
659 | because of alignment and bookkeeping overhead. Because it includes | |
660 | alignment wastage as being in use, this figure may be greater than | |
661 | zero even when no user-level chunks are allocated. | |
662 | ||
663 | The reported current and maximum system memory can be inaccurate if | |
664 | a program makes other calls to system memory allocation functions | |
665 | (normally sbrk) outside of malloc. | |
666 | ||
667 | malloc_stats prints only the most commonly interesting statistics. | |
668 | More information can be obtained by calling mallinfo. | |
669 | ||
670 | */ | |
3b49edc0 | 671 | void __malloc_stats(void); |
f65fd747 | 672 | |
f7ddf3d3 UD |
673 | /* |
674 | malloc_get_state(void); | |
675 | ||
676 | Returns the state of all malloc variables in an opaque data | |
677 | structure. | |
678 | */ | |
3b49edc0 | 679 | void* __malloc_get_state(void); |
f7ddf3d3 UD |
680 | |
681 | /* | |
22a89187 | 682 | malloc_set_state(void* state); |
f7ddf3d3 UD |
683 | |
684 | Restore the state of all malloc variables from data obtained with | |
685 | malloc_get_state(). | |
686 | */ | |
3b49edc0 | 687 | int __malloc_set_state(void*); |
f7ddf3d3 | 688 | |
f7ddf3d3 UD |
689 | /* |
690 | posix_memalign(void **memptr, size_t alignment, size_t size); | |
691 | ||
692 | POSIX wrapper like memalign(), checking for validity of size. | |
693 | */ | |
694 | int __posix_memalign(void **, size_t, size_t); | |
f7ddf3d3 | 695 | |
fa8d436c UD |
696 | /* mallopt tuning options */ |
697 | ||
f65fd747 | 698 | /* |
fa8d436c UD |
699 | M_MXFAST is the maximum request size used for "fastbins", special bins |
700 | that hold returned chunks without consolidating their spaces. This | |
701 | enables future requests for chunks of the same size to be handled | |
702 | very quickly, but can increase fragmentation, and thus increase the | |
703 | overall memory footprint of a program. | |
704 | ||
705 | This malloc manages fastbins very conservatively yet still | |
706 | efficiently, so fragmentation is rarely a problem for values less | |
707 | than or equal to the default. The maximum supported value of MXFAST | |
708 | is 80. You wouldn't want it any higher than this anyway. Fastbins | |
709 | are designed especially for use with many small structs, objects or | |
710 | strings -- the default handles structs/objects/arrays with sizes up | |
711 | to 8 4byte fields, or small strings representing words, tokens, | |
712 | etc. Using fastbins for larger objects normally worsens | |
713 | fragmentation without improving speed. | |
714 | ||
715 | M_MXFAST is set in REQUEST size units. It is internally used in | |
716 | chunksize units, which adds padding and alignment. You can reduce | |
717 | M_MXFAST to 0 to disable all use of fastbins. This causes the malloc | |
718 | algorithm to be a closer approximation of fifo-best-fit in all cases, | |
719 | not just for larger requests, but will generally cause it to be | |
720 | slower. | |
f65fd747 UD |
721 | */ |
722 | ||
723 | ||
fa8d436c UD |
724 | /* M_MXFAST is a standard SVID/XPG tuning option, usually listed in malloc.h */ |
725 | #ifndef M_MXFAST | |
a9177ff5 | 726 | #define M_MXFAST 1 |
fa8d436c | 727 | #endif |
f65fd747 | 728 | |
fa8d436c | 729 | #ifndef DEFAULT_MXFAST |
425ce2ed | 730 | #define DEFAULT_MXFAST (64 * SIZE_SZ / 4) |
10dc2a90 UD |
731 | #endif |
732 | ||
10dc2a90 | 733 | |
fa8d436c UD |
734 | /* |
735 | M_TRIM_THRESHOLD is the maximum amount of unused top-most memory | |
736 | to keep before releasing via malloc_trim in free(). | |
737 | ||
738 | Automatic trimming is mainly useful in long-lived programs. | |
739 | Because trimming via sbrk can be slow on some systems, and can | |
740 | sometimes be wasteful (in cases where programs immediately | |
741 | afterward allocate more large chunks) the value should be high | |
742 | enough so that your overall system performance would improve by | |
743 | releasing this much memory. | |
744 | ||
745 | The trim threshold and the mmap control parameters (see below) | |
746 | can be traded off with one another. Trimming and mmapping are | |
747 | two different ways of releasing unused memory back to the | |
748 | system. Between these two, it is often possible to keep | |
749 | system-level demands of a long-lived program down to a bare | |
750 | minimum. For example, in one test suite of sessions measuring | |
751 | the XF86 X server on Linux, using a trim threshold of 128K and a | |
752 | mmap threshold of 192K led to near-minimal long term resource | |
753 | consumption. | |
754 | ||
755 | If you are using this malloc in a long-lived program, it should | |
756 | pay to experiment with these values. As a rough guide, you | |
757 | might set to a value close to the average size of a process | |
758 | (program) running on your system. Releasing this much memory | |
759 | would allow such a process to run in memory. Generally, it's | |
760 | worth it to tune for trimming rather tham memory mapping when a | |
761 | program undergoes phases where several large chunks are | |
762 | allocated and released in ways that can reuse each other's | |
763 | storage, perhaps mixed with phases where there are no such | |
764 | chunks at all. And in well-behaved long-lived programs, | |
765 | controlling release of large blocks via trimming versus mapping | |
766 | is usually faster. | |
767 | ||
768 | However, in most programs, these parameters serve mainly as | |
769 | protection against the system-level effects of carrying around | |
770 | massive amounts of unneeded memory. Since frequent calls to | |
771 | sbrk, mmap, and munmap otherwise degrade performance, the default | |
772 | parameters are set to relatively high values that serve only as | |
773 | safeguards. | |
774 | ||
775 | The trim value It must be greater than page size to have any useful | |
a9177ff5 | 776 | effect. To disable trimming completely, you can set to |
fa8d436c UD |
777 | (unsigned long)(-1) |
778 | ||
779 | Trim settings interact with fastbin (MXFAST) settings: Unless | |
780 | TRIM_FASTBINS is defined, automatic trimming never takes place upon | |
781 | freeing a chunk with size less than or equal to MXFAST. Trimming is | |
782 | instead delayed until subsequent freeing of larger chunks. However, | |
783 | you can still force an attempted trim by calling malloc_trim. | |
784 | ||
785 | Also, trimming is not generally possible in cases where | |
786 | the main arena is obtained via mmap. | |
787 | ||
788 | Note that the trick some people use of mallocing a huge space and | |
789 | then freeing it at program startup, in an attempt to reserve system | |
790 | memory, doesn't have the intended effect under automatic trimming, | |
791 | since that memory will immediately be returned to the system. | |
792 | */ | |
793 | ||
794 | #define M_TRIM_THRESHOLD -1 | |
795 | ||
796 | #ifndef DEFAULT_TRIM_THRESHOLD | |
797 | #define DEFAULT_TRIM_THRESHOLD (128 * 1024) | |
798 | #endif | |
799 | ||
800 | /* | |
801 | M_TOP_PAD is the amount of extra `padding' space to allocate or | |
802 | retain whenever sbrk is called. It is used in two ways internally: | |
803 | ||
804 | * When sbrk is called to extend the top of the arena to satisfy | |
805 | a new malloc request, this much padding is added to the sbrk | |
806 | request. | |
807 | ||
808 | * When malloc_trim is called automatically from free(), | |
809 | it is used as the `pad' argument. | |
810 | ||
811 | In both cases, the actual amount of padding is rounded | |
812 | so that the end of the arena is always a system page boundary. | |
813 | ||
814 | The main reason for using padding is to avoid calling sbrk so | |
815 | often. Having even a small pad greatly reduces the likelihood | |
816 | that nearly every malloc request during program start-up (or | |
817 | after trimming) will invoke sbrk, which needlessly wastes | |
818 | time. | |
819 | ||
820 | Automatic rounding-up to page-size units is normally sufficient | |
821 | to avoid measurable overhead, so the default is 0. However, in | |
822 | systems where sbrk is relatively slow, it can pay to increase | |
823 | this value, at the expense of carrying around more memory than | |
824 | the program needs. | |
825 | */ | |
10dc2a90 | 826 | |
fa8d436c | 827 | #define M_TOP_PAD -2 |
10dc2a90 | 828 | |
fa8d436c UD |
829 | #ifndef DEFAULT_TOP_PAD |
830 | #define DEFAULT_TOP_PAD (0) | |
831 | #endif | |
f65fd747 | 832 | |
1d05c2fb UD |
833 | /* |
834 | MMAP_THRESHOLD_MAX and _MIN are the bounds on the dynamically | |
835 | adjusted MMAP_THRESHOLD. | |
836 | */ | |
837 | ||
838 | #ifndef DEFAULT_MMAP_THRESHOLD_MIN | |
839 | #define DEFAULT_MMAP_THRESHOLD_MIN (128 * 1024) | |
840 | #endif | |
841 | ||
842 | #ifndef DEFAULT_MMAP_THRESHOLD_MAX | |
e404fb16 UD |
843 | /* For 32-bit platforms we cannot increase the maximum mmap |
844 | threshold much because it is also the minimum value for the | |
bd2c2341 UD |
845 | maximum heap size and its alignment. Going above 512k (i.e., 1M |
846 | for new heaps) wastes too much address space. */ | |
e404fb16 | 847 | # if __WORDSIZE == 32 |
bd2c2341 | 848 | # define DEFAULT_MMAP_THRESHOLD_MAX (512 * 1024) |
e404fb16 | 849 | # else |
bd2c2341 | 850 | # define DEFAULT_MMAP_THRESHOLD_MAX (4 * 1024 * 1024 * sizeof(long)) |
e404fb16 | 851 | # endif |
1d05c2fb UD |
852 | #endif |
853 | ||
fa8d436c UD |
854 | /* |
855 | M_MMAP_THRESHOLD is the request size threshold for using mmap() | |
856 | to service a request. Requests of at least this size that cannot | |
857 | be allocated using already-existing space will be serviced via mmap. | |
858 | (If enough normal freed space already exists it is used instead.) | |
859 | ||
860 | Using mmap segregates relatively large chunks of memory so that | |
861 | they can be individually obtained and released from the host | |
862 | system. A request serviced through mmap is never reused by any | |
863 | other request (at least not directly; the system may just so | |
864 | happen to remap successive requests to the same locations). | |
865 | ||
866 | Segregating space in this way has the benefits that: | |
867 | ||
a9177ff5 RM |
868 | 1. Mmapped space can ALWAYS be individually released back |
869 | to the system, which helps keep the system level memory | |
870 | demands of a long-lived program low. | |
fa8d436c UD |
871 | 2. Mapped memory can never become `locked' between |
872 | other chunks, as can happen with normally allocated chunks, which | |
873 | means that even trimming via malloc_trim would not release them. | |
874 | 3. On some systems with "holes" in address spaces, mmap can obtain | |
875 | memory that sbrk cannot. | |
876 | ||
877 | However, it has the disadvantages that: | |
878 | ||
879 | 1. The space cannot be reclaimed, consolidated, and then | |
880 | used to service later requests, as happens with normal chunks. | |
881 | 2. It can lead to more wastage because of mmap page alignment | |
882 | requirements | |
883 | 3. It causes malloc performance to be more dependent on host | |
884 | system memory management support routines which may vary in | |
885 | implementation quality and may impose arbitrary | |
886 | limitations. Generally, servicing a request via normal | |
887 | malloc steps is faster than going through a system's mmap. | |
888 | ||
889 | The advantages of mmap nearly always outweigh disadvantages for | |
890 | "large" chunks, but the value of "large" varies across systems. The | |
891 | default is an empirically derived value that works well in most | |
892 | systems. | |
1d05c2fb UD |
893 | |
894 | ||
895 | Update in 2006: | |
896 | The above was written in 2001. Since then the world has changed a lot. | |
897 | Memory got bigger. Applications got bigger. The virtual address space | |
898 | layout in 32 bit linux changed. | |
899 | ||
900 | In the new situation, brk() and mmap space is shared and there are no | |
901 | artificial limits on brk size imposed by the kernel. What is more, | |
902 | applications have started using transient allocations larger than the | |
903 | 128Kb as was imagined in 2001. | |
904 | ||
905 | The price for mmap is also high now; each time glibc mmaps from the | |
906 | kernel, the kernel is forced to zero out the memory it gives to the | |
907 | application. Zeroing memory is expensive and eats a lot of cache and | |
908 | memory bandwidth. This has nothing to do with the efficiency of the | |
909 | virtual memory system, by doing mmap the kernel just has no choice but | |
910 | to zero. | |
911 | ||
912 | In 2001, the kernel had a maximum size for brk() which was about 800 | |
913 | megabytes on 32 bit x86, at that point brk() would hit the first | |
914 | mmaped shared libaries and couldn't expand anymore. With current 2.6 | |
915 | kernels, the VA space layout is different and brk() and mmap | |
916 | both can span the entire heap at will. | |
917 | ||
918 | Rather than using a static threshold for the brk/mmap tradeoff, | |
919 | we are now using a simple dynamic one. The goal is still to avoid | |
920 | fragmentation. The old goals we kept are | |
921 | 1) try to get the long lived large allocations to use mmap() | |
922 | 2) really large allocations should always use mmap() | |
923 | and we're adding now: | |
924 | 3) transient allocations should use brk() to avoid forcing the kernel | |
925 | having to zero memory over and over again | |
926 | ||
927 | The implementation works with a sliding threshold, which is by default | |
928 | limited to go between 128Kb and 32Mb (64Mb for 64 bitmachines) and starts | |
929 | out at 128Kb as per the 2001 default. | |
930 | ||
931 | This allows us to satisfy requirement 1) under the assumption that long | |
932 | lived allocations are made early in the process' lifespan, before it has | |
933 | started doing dynamic allocations of the same size (which will | |
934 | increase the threshold). | |
935 | ||
936 | The upperbound on the threshold satisfies requirement 2) | |
937 | ||
938 | The threshold goes up in value when the application frees memory that was | |
939 | allocated with the mmap allocator. The idea is that once the application | |
940 | starts freeing memory of a certain size, it's highly probable that this is | |
941 | a size the application uses for transient allocations. This estimator | |
942 | is there to satisfy the new third requirement. | |
943 | ||
f65fd747 UD |
944 | */ |
945 | ||
fa8d436c | 946 | #define M_MMAP_THRESHOLD -3 |
f65fd747 | 947 | |
fa8d436c | 948 | #ifndef DEFAULT_MMAP_THRESHOLD |
1d05c2fb | 949 | #define DEFAULT_MMAP_THRESHOLD DEFAULT_MMAP_THRESHOLD_MIN |
fa8d436c UD |
950 | #endif |
951 | ||
952 | /* | |
953 | M_MMAP_MAX is the maximum number of requests to simultaneously | |
954 | service using mmap. This parameter exists because | |
955 | some systems have a limited number of internal tables for | |
956 | use by mmap, and using more than a few of them may degrade | |
957 | performance. | |
958 | ||
959 | The default is set to a value that serves only as a safeguard. | |
22a89187 | 960 | Setting to 0 disables use of mmap for servicing large requests. |
fa8d436c | 961 | */ |
f65fd747 | 962 | |
fa8d436c UD |
963 | #define M_MMAP_MAX -4 |
964 | ||
965 | #ifndef DEFAULT_MMAP_MAX | |
fa8d436c | 966 | #define DEFAULT_MMAP_MAX (65536) |
f65fd747 UD |
967 | #endif |
968 | ||
100351c3 | 969 | #include <malloc.h> |
f65fd747 | 970 | |
fa8d436c UD |
971 | #ifndef RETURN_ADDRESS |
972 | #define RETURN_ADDRESS(X_) (NULL) | |
9ae6fc54 | 973 | #endif |
431c33c0 UD |
974 | |
975 | /* On some platforms we can compile internal, not exported functions better. | |
976 | Let the environment provide a macro and define it to be empty if it | |
977 | is not available. */ | |
978 | #ifndef internal_function | |
979 | # define internal_function | |
980 | #endif | |
981 | ||
fa8d436c UD |
982 | /* Forward declarations. */ |
983 | struct malloc_chunk; | |
984 | typedef struct malloc_chunk* mchunkptr; | |
431c33c0 | 985 | |
fa8d436c | 986 | /* Internal routines. */ |
f65fd747 | 987 | |
22a89187 | 988 | static void* _int_malloc(mstate, size_t); |
425ce2ed | 989 | static void _int_free(mstate, mchunkptr, int); |
22a89187 | 990 | static void* _int_realloc(mstate, mchunkptr, INTERNAL_SIZE_T, |
6e4b2107 | 991 | INTERNAL_SIZE_T); |
22a89187 | 992 | static void* _int_memalign(mstate, size_t, size_t); |
10ad46bc OB |
993 | static void* _mid_memalign(size_t, size_t, void *); |
994 | ||
fff94fa2 | 995 | static void malloc_printerr(int action, const char *str, void *ptr, mstate av); |
fa8d436c | 996 | |
22a89187 | 997 | static void* internal_function mem2mem_check(void *p, size_t sz); |
fa8d436c UD |
998 | static int internal_function top_check(void); |
999 | static void internal_function munmap_chunk(mchunkptr p); | |
a9177ff5 | 1000 | #if HAVE_MREMAP |
fa8d436c | 1001 | static mchunkptr internal_function mremap_chunk(mchunkptr p, size_t new_size); |
a9177ff5 | 1002 | #endif |
fa8d436c | 1003 | |
22a89187 UD |
1004 | static void* malloc_check(size_t sz, const void *caller); |
1005 | static void free_check(void* mem, const void *caller); | |
1006 | static void* realloc_check(void* oldmem, size_t bytes, | |
1007 | const void *caller); | |
1008 | static void* memalign_check(size_t alignment, size_t bytes, | |
1009 | const void *caller); | |
f65fd747 | 1010 | |
fa8d436c | 1011 | /* ------------------ MMAP support ------------------ */ |
f65fd747 | 1012 | |
f65fd747 | 1013 | |
fa8d436c | 1014 | #include <fcntl.h> |
fa8d436c | 1015 | #include <sys/mman.h> |
f65fd747 | 1016 | |
fa8d436c UD |
1017 | #if !defined(MAP_ANONYMOUS) && defined(MAP_ANON) |
1018 | # define MAP_ANONYMOUS MAP_ANON | |
1019 | #endif | |
f65fd747 | 1020 | |
fa8d436c | 1021 | #ifndef MAP_NORESERVE |
3b49edc0 | 1022 | # define MAP_NORESERVE 0 |
f65fd747 UD |
1023 | #endif |
1024 | ||
fa8d436c | 1025 | #define MMAP(addr, size, prot, flags) \ |
3b49edc0 | 1026 | __mmap((addr), (size), (prot), (flags)|MAP_ANONYMOUS|MAP_PRIVATE, -1, 0) |
f65fd747 | 1027 | |
f65fd747 UD |
1028 | |
1029 | /* | |
fa8d436c | 1030 | ----------------------- Chunk representations ----------------------- |
f65fd747 UD |
1031 | */ |
1032 | ||
1033 | ||
fa8d436c UD |
1034 | /* |
1035 | This struct declaration is misleading (but accurate and necessary). | |
1036 | It declares a "view" into memory allowing access to necessary | |
1037 | fields at known offsets from a given base. See explanation below. | |
1038 | */ | |
1039 | ||
1040 | struct malloc_chunk { | |
1041 | ||
e9c4fe93 FW |
1042 | INTERNAL_SIZE_T mchunk_prev_size; /* Size of previous chunk (if free). */ |
1043 | INTERNAL_SIZE_T mchunk_size; /* Size in bytes, including overhead. */ | |
fa8d436c UD |
1044 | |
1045 | struct malloc_chunk* fd; /* double links -- used only if free. */ | |
f65fd747 | 1046 | struct malloc_chunk* bk; |
7ecfbd38 UD |
1047 | |
1048 | /* Only used for large blocks: pointer to next larger size. */ | |
1049 | struct malloc_chunk* fd_nextsize; /* double links -- used only if free. */ | |
1050 | struct malloc_chunk* bk_nextsize; | |
f65fd747 UD |
1051 | }; |
1052 | ||
f65fd747 UD |
1053 | |
1054 | /* | |
f65fd747 UD |
1055 | malloc_chunk details: |
1056 | ||
1057 | (The following includes lightly edited explanations by Colin Plumb.) | |
1058 | ||
1059 | Chunks of memory are maintained using a `boundary tag' method as | |
1060 | described in e.g., Knuth or Standish. (See the paper by Paul | |
1061 | Wilson ftp://ftp.cs.utexas.edu/pub/garbage/allocsrv.ps for a | |
1062 | survey of such techniques.) Sizes of free chunks are stored both | |
1063 | in the front of each chunk and at the end. This makes | |
1064 | consolidating fragmented chunks into bigger chunks very fast. The | |
1065 | size fields also hold bits representing whether chunks are free or | |
1066 | in use. | |
1067 | ||
1068 | An allocated chunk looks like this: | |
1069 | ||
1070 | ||
1071 | chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
ae9166f2 | 1072 | | Size of previous chunk, if unallocated (P clear) | |
72f90263 | 1073 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
ae9166f2 | 1074 | | Size of chunk, in bytes |A|M|P| |
f65fd747 | 1075 | mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
72f90263 UD |
1076 | | User data starts here... . |
1077 | . . | |
1078 | . (malloc_usable_size() bytes) . | |
1079 | . | | |
f65fd747 | 1080 | nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
ae9166f2 FW |
1081 | | (size of chunk, but used for application data) | |
1082 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
1083 | | Size of next chunk, in bytes |A|0|1| | |
72f90263 | 1084 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
f65fd747 UD |
1085 | |
1086 | Where "chunk" is the front of the chunk for the purpose of most of | |
1087 | the malloc code, but "mem" is the pointer that is returned to the | |
1088 | user. "Nextchunk" is the beginning of the next contiguous chunk. | |
1089 | ||
6f65e668 | 1090 | Chunks always begin on even word boundaries, so the mem portion |
f65fd747 | 1091 | (which is returned to the user) is also on an even word boundary, and |
fa8d436c | 1092 | thus at least double-word aligned. |
f65fd747 UD |
1093 | |
1094 | Free chunks are stored in circular doubly-linked lists, and look like this: | |
1095 | ||
1096 | chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
ae9166f2 | 1097 | | Size of previous chunk, if unallocated (P clear) | |
72f90263 | 1098 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
ae9166f2 | 1099 | `head:' | Size of chunk, in bytes |A|0|P| |
f65fd747 | 1100 | mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
72f90263 UD |
1101 | | Forward pointer to next chunk in list | |
1102 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
1103 | | Back pointer to previous chunk in list | | |
1104 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
1105 | | Unused space (may be 0 bytes long) . | |
1106 | . . | |
1107 | . | | |
f65fd747 UD |
1108 | nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
1109 | `foot:' | Size of chunk, in bytes | | |
72f90263 | 1110 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
ae9166f2 FW |
1111 | | Size of next chunk, in bytes |A|0|0| |
1112 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
f65fd747 UD |
1113 | |
1114 | The P (PREV_INUSE) bit, stored in the unused low-order bit of the | |
1115 | chunk size (which is always a multiple of two words), is an in-use | |
1116 | bit for the *previous* chunk. If that bit is *clear*, then the | |
1117 | word before the current chunk size contains the previous chunk | |
1118 | size, and can be used to find the front of the previous chunk. | |
fa8d436c UD |
1119 | The very first chunk allocated always has this bit set, |
1120 | preventing access to non-existent (or non-owned) memory. If | |
1121 | prev_inuse is set for any given chunk, then you CANNOT determine | |
1122 | the size of the previous chunk, and might even get a memory | |
1123 | addressing fault when trying to do so. | |
f65fd747 | 1124 | |
ae9166f2 FW |
1125 | The A (NON_MAIN_ARENA) bit is cleared for chunks on the initial, |
1126 | main arena, described by the main_arena variable. When additional | |
1127 | threads are spawned, each thread receives its own arena (up to a | |
1128 | configurable limit, after which arenas are reused for multiple | |
1129 | threads), and the chunks in these arenas have the A bit set. To | |
1130 | find the arena for a chunk on such a non-main arena, heap_for_ptr | |
1131 | performs a bit mask operation and indirection through the ar_ptr | |
1132 | member of the per-heap header heap_info (see arena.c). | |
1133 | ||
f65fd747 | 1134 | Note that the `foot' of the current chunk is actually represented |
fa8d436c UD |
1135 | as the prev_size of the NEXT chunk. This makes it easier to |
1136 | deal with alignments etc but can be very confusing when trying | |
1137 | to extend or adapt this code. | |
f65fd747 | 1138 | |
ae9166f2 | 1139 | The three exceptions to all this are: |
f65fd747 | 1140 | |
fa8d436c | 1141 | 1. The special chunk `top' doesn't bother using the |
72f90263 UD |
1142 | trailing size field since there is no next contiguous chunk |
1143 | that would have to index off it. After initialization, `top' | |
1144 | is forced to always exist. If it would become less than | |
1145 | MINSIZE bytes long, it is replenished. | |
f65fd747 UD |
1146 | |
1147 | 2. Chunks allocated via mmap, which have the second-lowest-order | |
72f90263 | 1148 | bit M (IS_MMAPPED) set in their size fields. Because they are |
ae9166f2 FW |
1149 | allocated one-by-one, each must contain its own trailing size |
1150 | field. If the M bit is set, the other bits are ignored | |
1151 | (because mmapped chunks are neither in an arena, nor adjacent | |
1152 | to a freed chunk). The M bit is also used for chunks which | |
1153 | originally came from a dumped heap via malloc_set_state in | |
1154 | hooks.c. | |
1155 | ||
1156 | 3. Chunks in fastbins are treated as allocated chunks from the | |
1157 | point of view of the chunk allocator. They are consolidated | |
1158 | with their neighbors only in bulk, in malloc_consolidate. | |
f65fd747 UD |
1159 | */ |
1160 | ||
1161 | /* | |
fa8d436c UD |
1162 | ---------- Size and alignment checks and conversions ---------- |
1163 | */ | |
f65fd747 | 1164 | |
fa8d436c | 1165 | /* conversion from malloc headers to user pointers, and back */ |
f65fd747 | 1166 | |
22a89187 | 1167 | #define chunk2mem(p) ((void*)((char*)(p) + 2*SIZE_SZ)) |
fa8d436c | 1168 | #define mem2chunk(mem) ((mchunkptr)((char*)(mem) - 2*SIZE_SZ)) |
f65fd747 | 1169 | |
fa8d436c | 1170 | /* The smallest possible chunk */ |
7ecfbd38 | 1171 | #define MIN_CHUNK_SIZE (offsetof(struct malloc_chunk, fd_nextsize)) |
f65fd747 | 1172 | |
fa8d436c | 1173 | /* The smallest size we can malloc is an aligned minimal chunk */ |
f65fd747 | 1174 | |
fa8d436c UD |
1175 | #define MINSIZE \ |
1176 | (unsigned long)(((MIN_CHUNK_SIZE+MALLOC_ALIGN_MASK) & ~MALLOC_ALIGN_MASK)) | |
f65fd747 | 1177 | |
fa8d436c | 1178 | /* Check if m has acceptable alignment */ |
f65fd747 | 1179 | |
073f560e UD |
1180 | #define aligned_OK(m) (((unsigned long)(m) & MALLOC_ALIGN_MASK) == 0) |
1181 | ||
1182 | #define misaligned_chunk(p) \ | |
1183 | ((uintptr_t)(MALLOC_ALIGNMENT == 2 * SIZE_SZ ? (p) : chunk2mem (p)) \ | |
1184 | & MALLOC_ALIGN_MASK) | |
f65fd747 | 1185 | |
f65fd747 | 1186 | |
a9177ff5 | 1187 | /* |
fa8d436c UD |
1188 | Check if a request is so large that it would wrap around zero when |
1189 | padded and aligned. To simplify some other code, the bound is made | |
1190 | low enough so that adding MINSIZE will also not wrap around zero. | |
6c8dbf00 | 1191 | */ |
f65fd747 | 1192 | |
fa8d436c | 1193 | #define REQUEST_OUT_OF_RANGE(req) \ |
6c8dbf00 OB |
1194 | ((unsigned long) (req) >= \ |
1195 | (unsigned long) (INTERNAL_SIZE_T) (-2 * MINSIZE)) | |
f65fd747 | 1196 | |
fa8d436c | 1197 | /* pad request bytes into a usable size -- internal version */ |
f65fd747 | 1198 | |
fa8d436c UD |
1199 | #define request2size(req) \ |
1200 | (((req) + SIZE_SZ + MALLOC_ALIGN_MASK < MINSIZE) ? \ | |
1201 | MINSIZE : \ | |
1202 | ((req) + SIZE_SZ + MALLOC_ALIGN_MASK) & ~MALLOC_ALIGN_MASK) | |
f65fd747 | 1203 | |
fa8d436c | 1204 | /* Same, except also perform argument check */ |
f65fd747 | 1205 | |
fa8d436c | 1206 | #define checked_request2size(req, sz) \ |
6c8dbf00 OB |
1207 | if (REQUEST_OUT_OF_RANGE (req)) { \ |
1208 | __set_errno (ENOMEM); \ | |
1209 | return 0; \ | |
1210 | } \ | |
1211 | (sz) = request2size (req); | |
f65fd747 UD |
1212 | |
1213 | /* | |
6c8dbf00 OB |
1214 | --------------- Physical chunk operations --------------- |
1215 | */ | |
f65fd747 | 1216 | |
10dc2a90 | 1217 | |
fa8d436c UD |
1218 | /* size field is or'ed with PREV_INUSE when previous adjacent chunk in use */ |
1219 | #define PREV_INUSE 0x1 | |
f65fd747 | 1220 | |
fa8d436c | 1221 | /* extract inuse bit of previous chunk */ |
e9c4fe93 | 1222 | #define prev_inuse(p) ((p)->mchunk_size & PREV_INUSE) |
f65fd747 | 1223 | |
f65fd747 | 1224 | |
fa8d436c UD |
1225 | /* size field is or'ed with IS_MMAPPED if the chunk was obtained with mmap() */ |
1226 | #define IS_MMAPPED 0x2 | |
f65fd747 | 1227 | |
fa8d436c | 1228 | /* check for mmap()'ed chunk */ |
e9c4fe93 | 1229 | #define chunk_is_mmapped(p) ((p)->mchunk_size & IS_MMAPPED) |
f65fd747 | 1230 | |
f65fd747 | 1231 | |
fa8d436c UD |
1232 | /* size field is or'ed with NON_MAIN_ARENA if the chunk was obtained |
1233 | from a non-main arena. This is only set immediately before handing | |
1234 | the chunk to the user, if necessary. */ | |
1235 | #define NON_MAIN_ARENA 0x4 | |
f65fd747 | 1236 | |
ae9166f2 | 1237 | /* Check for chunk from main arena. */ |
e9c4fe93 FW |
1238 | #define chunk_main_arena(p) (((p)->mchunk_size & NON_MAIN_ARENA) == 0) |
1239 | ||
1240 | /* Mark a chunk as not being on the main arena. */ | |
1241 | #define set_non_main_arena(p) ((p)->mchunk_size |= NON_MAIN_ARENA) | |
f65fd747 UD |
1242 | |
1243 | ||
a9177ff5 | 1244 | /* |
6c8dbf00 | 1245 | Bits to mask off when extracting size |
f65fd747 | 1246 | |
6c8dbf00 OB |
1247 | Note: IS_MMAPPED is intentionally not masked off from size field in |
1248 | macros for which mmapped chunks should never be seen. This should | |
1249 | cause helpful core dumps to occur if it is tried by accident by | |
1250 | people extending or adapting this malloc. | |
1251 | */ | |
1252 | #define SIZE_BITS (PREV_INUSE | IS_MMAPPED | NON_MAIN_ARENA) | |
f65fd747 | 1253 | |
fa8d436c | 1254 | /* Get size, ignoring use bits */ |
e9c4fe93 | 1255 | #define chunksize(p) (chunksize_nomask (p) & ~(SIZE_BITS)) |
f65fd747 | 1256 | |
e9c4fe93 FW |
1257 | /* Like chunksize, but do not mask SIZE_BITS. */ |
1258 | #define chunksize_nomask(p) ((p)->mchunk_size) | |
f65fd747 | 1259 | |
fa8d436c | 1260 | /* Ptr to next physical malloc_chunk. */ |
e9c4fe93 FW |
1261 | #define next_chunk(p) ((mchunkptr) (((char *) (p)) + chunksize (p))) |
1262 | ||
1263 | /* Size of the chunk below P. Only valid if prev_inuse (P). */ | |
1264 | #define prev_size(p) ((p)->mchunk_prev_size) | |
1265 | ||
1266 | /* Set the size of the chunk below P. Only valid if prev_inuse (P). */ | |
1267 | #define set_prev_size(p, sz) ((p)->mchunk_prev_size = (sz)) | |
f65fd747 | 1268 | |
e9c4fe93 FW |
1269 | /* Ptr to previous physical malloc_chunk. Only valid if prev_inuse (P). */ |
1270 | #define prev_chunk(p) ((mchunkptr) (((char *) (p)) - prev_size (p))) | |
f65fd747 | 1271 | |
fa8d436c | 1272 | /* Treat space at ptr + offset as a chunk */ |
6c8dbf00 | 1273 | #define chunk_at_offset(p, s) ((mchunkptr) (((char *) (p)) + (s))) |
fa8d436c UD |
1274 | |
1275 | /* extract p's inuse bit */ | |
6c8dbf00 | 1276 | #define inuse(p) \ |
e9c4fe93 | 1277 | ((((mchunkptr) (((char *) (p)) + chunksize (p)))->mchunk_size) & PREV_INUSE) |
f65fd747 | 1278 | |
fa8d436c | 1279 | /* set/clear chunk as being inuse without otherwise disturbing */ |
6c8dbf00 | 1280 | #define set_inuse(p) \ |
e9c4fe93 | 1281 | ((mchunkptr) (((char *) (p)) + chunksize (p)))->mchunk_size |= PREV_INUSE |
f65fd747 | 1282 | |
6c8dbf00 | 1283 | #define clear_inuse(p) \ |
e9c4fe93 | 1284 | ((mchunkptr) (((char *) (p)) + chunksize (p)))->mchunk_size &= ~(PREV_INUSE) |
f65fd747 UD |
1285 | |
1286 | ||
fa8d436c | 1287 | /* check/set/clear inuse bits in known places */ |
6c8dbf00 | 1288 | #define inuse_bit_at_offset(p, s) \ |
e9c4fe93 | 1289 | (((mchunkptr) (((char *) (p)) + (s)))->mchunk_size & PREV_INUSE) |
f65fd747 | 1290 | |
6c8dbf00 | 1291 | #define set_inuse_bit_at_offset(p, s) \ |
e9c4fe93 | 1292 | (((mchunkptr) (((char *) (p)) + (s)))->mchunk_size |= PREV_INUSE) |
f65fd747 | 1293 | |
6c8dbf00 | 1294 | #define clear_inuse_bit_at_offset(p, s) \ |
e9c4fe93 | 1295 | (((mchunkptr) (((char *) (p)) + (s)))->mchunk_size &= ~(PREV_INUSE)) |
f65fd747 | 1296 | |
f65fd747 | 1297 | |
fa8d436c | 1298 | /* Set size at head, without disturbing its use bit */ |
e9c4fe93 | 1299 | #define set_head_size(p, s) ((p)->mchunk_size = (((p)->mchunk_size & SIZE_BITS) | (s))) |
f65fd747 | 1300 | |
fa8d436c | 1301 | /* Set size/use field */ |
e9c4fe93 | 1302 | #define set_head(p, s) ((p)->mchunk_size = (s)) |
f65fd747 | 1303 | |
fa8d436c | 1304 | /* Set size at footer (only when chunk is not in use) */ |
e9c4fe93 | 1305 | #define set_foot(p, s) (((mchunkptr) ((char *) (p) + (s)))->mchunk_prev_size = (s)) |
f65fd747 UD |
1306 | |
1307 | ||
e9c4fe93 FW |
1308 | #pragma GCC poison mchunk_size |
1309 | #pragma GCC poison mchunk_prev_size | |
1310 | ||
fa8d436c | 1311 | /* |
6c8dbf00 | 1312 | -------------------- Internal data structures -------------------- |
fa8d436c UD |
1313 | |
1314 | All internal state is held in an instance of malloc_state defined | |
1315 | below. There are no other static variables, except in two optional | |
a9177ff5 | 1316 | cases: |
6c8dbf00 OB |
1317 | * If USE_MALLOC_LOCK is defined, the mALLOC_MUTEx declared above. |
1318 | * If mmap doesn't support MAP_ANONYMOUS, a dummy file descriptor | |
22a89187 | 1319 | for mmap. |
fa8d436c UD |
1320 | |
1321 | Beware of lots of tricks that minimize the total bookkeeping space | |
1322 | requirements. The result is a little over 1K bytes (for 4byte | |
1323 | pointers and size_t.) | |
6c8dbf00 | 1324 | */ |
f65fd747 UD |
1325 | |
1326 | /* | |
6c8dbf00 | 1327 | Bins |
fa8d436c UD |
1328 | |
1329 | An array of bin headers for free chunks. Each bin is doubly | |
1330 | linked. The bins are approximately proportionally (log) spaced. | |
1331 | There are a lot of these bins (128). This may look excessive, but | |
1332 | works very well in practice. Most bins hold sizes that are | |
1333 | unusual as malloc request sizes, but are more usual for fragments | |
1334 | and consolidated sets of chunks, which is what these bins hold, so | |
1335 | they can be found quickly. All procedures maintain the invariant | |
1336 | that no consolidated chunk physically borders another one, so each | |
1337 | chunk in a list is known to be preceeded and followed by either | |
1338 | inuse chunks or the ends of memory. | |
1339 | ||
1340 | Chunks in bins are kept in size order, with ties going to the | |
1341 | approximately least recently used chunk. Ordering isn't needed | |
1342 | for the small bins, which all contain the same-sized chunks, but | |
1343 | facilitates best-fit allocation for larger chunks. These lists | |
1344 | are just sequential. Keeping them in order almost never requires | |
1345 | enough traversal to warrant using fancier ordered data | |
a9177ff5 | 1346 | structures. |
fa8d436c UD |
1347 | |
1348 | Chunks of the same size are linked with the most | |
1349 | recently freed at the front, and allocations are taken from the | |
1350 | back. This results in LRU (FIFO) allocation order, which tends | |
1351 | to give each chunk an equal opportunity to be consolidated with | |
1352 | adjacent freed chunks, resulting in larger free chunks and less | |
1353 | fragmentation. | |
1354 | ||
1355 | To simplify use in double-linked lists, each bin header acts | |
1356 | as a malloc_chunk. This avoids special-casing for headers. | |
1357 | But to conserve space and improve locality, we allocate | |
1358 | only the fd/bk pointers of bins, and then use repositioning tricks | |
a9177ff5 | 1359 | to treat these as the fields of a malloc_chunk*. |
6c8dbf00 | 1360 | */ |
f65fd747 | 1361 | |
6c8dbf00 | 1362 | typedef struct malloc_chunk *mbinptr; |
f65fd747 | 1363 | |
fa8d436c | 1364 | /* addressing -- note that bin_at(0) does not exist */ |
41999a1a UD |
1365 | #define bin_at(m, i) \ |
1366 | (mbinptr) (((char *) &((m)->bins[((i) - 1) * 2])) \ | |
6c8dbf00 | 1367 | - offsetof (struct malloc_chunk, fd)) |
f65fd747 | 1368 | |
fa8d436c | 1369 | /* analog of ++bin */ |
6c8dbf00 | 1370 | #define next_bin(b) ((mbinptr) ((char *) (b) + (sizeof (mchunkptr) << 1))) |
f65fd747 | 1371 | |
fa8d436c UD |
1372 | /* Reminders about list directionality within bins */ |
1373 | #define first(b) ((b)->fd) | |
1374 | #define last(b) ((b)->bk) | |
f65fd747 | 1375 | |
fa8d436c | 1376 | /* Take a chunk off a bin list */ |
fff94fa2 | 1377 | #define unlink(AV, P, BK, FD) { \ |
17f487b7 DD |
1378 | if (__builtin_expect (chunksize(P) != prev_size (next_chunk(P)), 0)) \ |
1379 | malloc_printerr (check_action, "corrupted size vs. prev_size", P, AV); \ | |
6c8dbf00 OB |
1380 | FD = P->fd; \ |
1381 | BK = P->bk; \ | |
1382 | if (__builtin_expect (FD->bk != P || BK->fd != P, 0)) \ | |
fff94fa2 | 1383 | malloc_printerr (check_action, "corrupted double-linked list", P, AV); \ |
6c8dbf00 OB |
1384 | else { \ |
1385 | FD->bk = BK; \ | |
1386 | BK->fd = FD; \ | |
e9c4fe93 | 1387 | if (!in_smallbin_range (chunksize_nomask (P)) \ |
6c8dbf00 | 1388 | && __builtin_expect (P->fd_nextsize != NULL, 0)) { \ |
52ffbdf2 FW |
1389 | if (__builtin_expect (P->fd_nextsize->bk_nextsize != P, 0) \ |
1390 | || __builtin_expect (P->bk_nextsize->fd_nextsize != P, 0)) \ | |
1391 | malloc_printerr (check_action, \ | |
fff94fa2 SP |
1392 | "corrupted double-linked list (not small)", \ |
1393 | P, AV); \ | |
6c8dbf00 OB |
1394 | if (FD->fd_nextsize == NULL) { \ |
1395 | if (P->fd_nextsize == P) \ | |
1396 | FD->fd_nextsize = FD->bk_nextsize = FD; \ | |
1397 | else { \ | |
1398 | FD->fd_nextsize = P->fd_nextsize; \ | |
1399 | FD->bk_nextsize = P->bk_nextsize; \ | |
1400 | P->fd_nextsize->bk_nextsize = FD; \ | |
1401 | P->bk_nextsize->fd_nextsize = FD; \ | |
1402 | } \ | |
1403 | } else { \ | |
1404 | P->fd_nextsize->bk_nextsize = P->bk_nextsize; \ | |
1405 | P->bk_nextsize->fd_nextsize = P->fd_nextsize; \ | |
1406 | } \ | |
1407 | } \ | |
1408 | } \ | |
fa8d436c | 1409 | } |
f65fd747 | 1410 | |
fa8d436c | 1411 | /* |
6c8dbf00 | 1412 | Indexing |
fa8d436c UD |
1413 | |
1414 | Bins for sizes < 512 bytes contain chunks of all the same size, spaced | |
1415 | 8 bytes apart. Larger bins are approximately logarithmically spaced: | |
f65fd747 | 1416 | |
fa8d436c UD |
1417 | 64 bins of size 8 |
1418 | 32 bins of size 64 | |
1419 | 16 bins of size 512 | |
1420 | 8 bins of size 4096 | |
1421 | 4 bins of size 32768 | |
1422 | 2 bins of size 262144 | |
1423 | 1 bin of size what's left | |
f65fd747 | 1424 | |
fa8d436c UD |
1425 | There is actually a little bit of slop in the numbers in bin_index |
1426 | for the sake of speed. This makes no difference elsewhere. | |
f65fd747 | 1427 | |
fa8d436c UD |
1428 | The bins top out around 1MB because we expect to service large |
1429 | requests via mmap. | |
b5a2bbe6 L |
1430 | |
1431 | Bin 0 does not exist. Bin 1 is the unordered list; if that would be | |
1432 | a valid chunk size the small bins are bumped up one. | |
6c8dbf00 | 1433 | */ |
f65fd747 | 1434 | |
fa8d436c UD |
1435 | #define NBINS 128 |
1436 | #define NSMALLBINS 64 | |
1d47e92f | 1437 | #define SMALLBIN_WIDTH MALLOC_ALIGNMENT |
b5a2bbe6 L |
1438 | #define SMALLBIN_CORRECTION (MALLOC_ALIGNMENT > 2 * SIZE_SZ) |
1439 | #define MIN_LARGE_SIZE ((NSMALLBINS - SMALLBIN_CORRECTION) * SMALLBIN_WIDTH) | |
f65fd747 | 1440 | |
fa8d436c | 1441 | #define in_smallbin_range(sz) \ |
6c8dbf00 | 1442 | ((unsigned long) (sz) < (unsigned long) MIN_LARGE_SIZE) |
f65fd747 | 1443 | |
1d47e92f | 1444 | #define smallbin_index(sz) \ |
6c8dbf00 | 1445 | ((SMALLBIN_WIDTH == 16 ? (((unsigned) (sz)) >> 4) : (((unsigned) (sz)) >> 3))\ |
b5a2bbe6 | 1446 | + SMALLBIN_CORRECTION) |
f65fd747 | 1447 | |
1d47e92f | 1448 | #define largebin_index_32(sz) \ |
6c8dbf00 OB |
1449 | (((((unsigned long) (sz)) >> 6) <= 38) ? 56 + (((unsigned long) (sz)) >> 6) :\ |
1450 | ((((unsigned long) (sz)) >> 9) <= 20) ? 91 + (((unsigned long) (sz)) >> 9) :\ | |
1451 | ((((unsigned long) (sz)) >> 12) <= 10) ? 110 + (((unsigned long) (sz)) >> 12) :\ | |
1452 | ((((unsigned long) (sz)) >> 15) <= 4) ? 119 + (((unsigned long) (sz)) >> 15) :\ | |
1453 | ((((unsigned long) (sz)) >> 18) <= 2) ? 124 + (((unsigned long) (sz)) >> 18) :\ | |
1454 | 126) | |
f65fd747 | 1455 | |
b5a2bbe6 | 1456 | #define largebin_index_32_big(sz) \ |
6c8dbf00 OB |
1457 | (((((unsigned long) (sz)) >> 6) <= 45) ? 49 + (((unsigned long) (sz)) >> 6) :\ |
1458 | ((((unsigned long) (sz)) >> 9) <= 20) ? 91 + (((unsigned long) (sz)) >> 9) :\ | |
1459 | ((((unsigned long) (sz)) >> 12) <= 10) ? 110 + (((unsigned long) (sz)) >> 12) :\ | |
1460 | ((((unsigned long) (sz)) >> 15) <= 4) ? 119 + (((unsigned long) (sz)) >> 15) :\ | |
1461 | ((((unsigned long) (sz)) >> 18) <= 2) ? 124 + (((unsigned long) (sz)) >> 18) :\ | |
1462 | 126) | |
b5a2bbe6 | 1463 | |
1d47e92f UD |
1464 | // XXX It remains to be seen whether it is good to keep the widths of |
1465 | // XXX the buckets the same or whether it should be scaled by a factor | |
1466 | // XXX of two as well. | |
1467 | #define largebin_index_64(sz) \ | |
6c8dbf00 OB |
1468 | (((((unsigned long) (sz)) >> 6) <= 48) ? 48 + (((unsigned long) (sz)) >> 6) :\ |
1469 | ((((unsigned long) (sz)) >> 9) <= 20) ? 91 + (((unsigned long) (sz)) >> 9) :\ | |
1470 | ((((unsigned long) (sz)) >> 12) <= 10) ? 110 + (((unsigned long) (sz)) >> 12) :\ | |
1471 | ((((unsigned long) (sz)) >> 15) <= 4) ? 119 + (((unsigned long) (sz)) >> 15) :\ | |
1472 | ((((unsigned long) (sz)) >> 18) <= 2) ? 124 + (((unsigned long) (sz)) >> 18) :\ | |
1473 | 126) | |
1d47e92f UD |
1474 | |
1475 | #define largebin_index(sz) \ | |
b5a2bbe6 L |
1476 | (SIZE_SZ == 8 ? largebin_index_64 (sz) \ |
1477 | : MALLOC_ALIGNMENT == 16 ? largebin_index_32_big (sz) \ | |
1478 | : largebin_index_32 (sz)) | |
1d47e92f | 1479 | |
fa8d436c | 1480 | #define bin_index(sz) \ |
6c8dbf00 | 1481 | ((in_smallbin_range (sz)) ? smallbin_index (sz) : largebin_index (sz)) |
f65fd747 | 1482 | |
f65fd747 UD |
1483 | |
1484 | /* | |
6c8dbf00 | 1485 | Unsorted chunks |
fa8d436c UD |
1486 | |
1487 | All remainders from chunk splits, as well as all returned chunks, | |
1488 | are first placed in the "unsorted" bin. They are then placed | |
1489 | in regular bins after malloc gives them ONE chance to be used before | |
1490 | binning. So, basically, the unsorted_chunks list acts as a queue, | |
1491 | with chunks being placed on it in free (and malloc_consolidate), | |
1492 | and taken off (to be either used or placed in bins) in malloc. | |
1493 | ||
1494 | The NON_MAIN_ARENA flag is never set for unsorted chunks, so it | |
1495 | does not have to be taken into account in size comparisons. | |
6c8dbf00 | 1496 | */ |
f65fd747 | 1497 | |
fa8d436c | 1498 | /* The otherwise unindexable 1-bin is used to hold unsorted chunks. */ |
6c8dbf00 | 1499 | #define unsorted_chunks(M) (bin_at (M, 1)) |
f65fd747 | 1500 | |
fa8d436c | 1501 | /* |
6c8dbf00 | 1502 | Top |
fa8d436c UD |
1503 | |
1504 | The top-most available chunk (i.e., the one bordering the end of | |
1505 | available memory) is treated specially. It is never included in | |
1506 | any bin, is used only if no other chunk is available, and is | |
1507 | released back to the system if it is very large (see | |
1508 | M_TRIM_THRESHOLD). Because top initially | |
1509 | points to its own bin with initial zero size, thus forcing | |
1510 | extension on the first malloc request, we avoid having any special | |
1511 | code in malloc to check whether it even exists yet. But we still | |
1512 | need to do so when getting memory from system, so we make | |
1513 | initial_top treat the bin as a legal but unusable chunk during the | |
1514 | interval between initialization and the first call to | |
3b49edc0 | 1515 | sysmalloc. (This is somewhat delicate, since it relies on |
fa8d436c | 1516 | the 2 preceding words to be zero during this interval as well.) |
6c8dbf00 | 1517 | */ |
f65fd747 | 1518 | |
fa8d436c | 1519 | /* Conveniently, the unsorted bin can be used as dummy top on first call */ |
6c8dbf00 | 1520 | #define initial_top(M) (unsorted_chunks (M)) |
f65fd747 | 1521 | |
fa8d436c | 1522 | /* |
6c8dbf00 | 1523 | Binmap |
f65fd747 | 1524 | |
fa8d436c UD |
1525 | To help compensate for the large number of bins, a one-level index |
1526 | structure is used for bin-by-bin searching. `binmap' is a | |
1527 | bitvector recording whether bins are definitely empty so they can | |
1528 | be skipped over during during traversals. The bits are NOT always | |
1529 | cleared as soon as bins are empty, but instead only | |
1530 | when they are noticed to be empty during traversal in malloc. | |
6c8dbf00 | 1531 | */ |
f65fd747 | 1532 | |
fa8d436c UD |
1533 | /* Conservatively use 32 bits per map word, even if on 64bit system */ |
1534 | #define BINMAPSHIFT 5 | |
1535 | #define BITSPERMAP (1U << BINMAPSHIFT) | |
1536 | #define BINMAPSIZE (NBINS / BITSPERMAP) | |
f65fd747 | 1537 | |
fa8d436c | 1538 | #define idx2block(i) ((i) >> BINMAPSHIFT) |
6c8dbf00 | 1539 | #define idx2bit(i) ((1U << ((i) & ((1U << BINMAPSHIFT) - 1)))) |
f65fd747 | 1540 | |
6c8dbf00 OB |
1541 | #define mark_bin(m, i) ((m)->binmap[idx2block (i)] |= idx2bit (i)) |
1542 | #define unmark_bin(m, i) ((m)->binmap[idx2block (i)] &= ~(idx2bit (i))) | |
1543 | #define get_binmap(m, i) ((m)->binmap[idx2block (i)] & idx2bit (i)) | |
f65fd747 | 1544 | |
fa8d436c | 1545 | /* |
6c8dbf00 | 1546 | Fastbins |
fa8d436c UD |
1547 | |
1548 | An array of lists holding recently freed small chunks. Fastbins | |
1549 | are not doubly linked. It is faster to single-link them, and | |
1550 | since chunks are never removed from the middles of these lists, | |
1551 | double linking is not necessary. Also, unlike regular bins, they | |
1552 | are not even processed in FIFO order (they use faster LIFO) since | |
1553 | ordering doesn't much matter in the transient contexts in which | |
1554 | fastbins are normally used. | |
1555 | ||
1556 | Chunks in fastbins keep their inuse bit set, so they cannot | |
1557 | be consolidated with other free chunks. malloc_consolidate | |
1558 | releases all chunks in fastbins and consolidates them with | |
a9177ff5 | 1559 | other free chunks. |
6c8dbf00 | 1560 | */ |
f65fd747 | 1561 | |
6c8dbf00 | 1562 | typedef struct malloc_chunk *mfastbinptr; |
425ce2ed | 1563 | #define fastbin(ar_ptr, idx) ((ar_ptr)->fastbinsY[idx]) |
f65fd747 | 1564 | |
fa8d436c | 1565 | /* offset 2 to use otherwise unindexable first 2 bins */ |
425ce2ed | 1566 | #define fastbin_index(sz) \ |
6c8dbf00 | 1567 | ((((unsigned int) (sz)) >> (SIZE_SZ == 8 ? 4 : 3)) - 2) |
425ce2ed | 1568 | |
f65fd747 | 1569 | |
fa8d436c | 1570 | /* The maximum fastbin request size we support */ |
425ce2ed | 1571 | #define MAX_FAST_SIZE (80 * SIZE_SZ / 4) |
f65fd747 | 1572 | |
6c8dbf00 | 1573 | #define NFASTBINS (fastbin_index (request2size (MAX_FAST_SIZE)) + 1) |
f65fd747 UD |
1574 | |
1575 | /* | |
6c8dbf00 OB |
1576 | FASTBIN_CONSOLIDATION_THRESHOLD is the size of a chunk in free() |
1577 | that triggers automatic consolidation of possibly-surrounding | |
1578 | fastbin chunks. This is a heuristic, so the exact value should not | |
1579 | matter too much. It is defined at half the default trim threshold as a | |
1580 | compromise heuristic to only attempt consolidation if it is likely | |
1581 | to lead to trimming. However, it is not dynamically tunable, since | |
1582 | consolidation reduces fragmentation surrounding large chunks even | |
1583 | if trimming is not used. | |
1584 | */ | |
f65fd747 | 1585 | |
fa8d436c | 1586 | #define FASTBIN_CONSOLIDATION_THRESHOLD (65536UL) |
f65fd747 UD |
1587 | |
1588 | /* | |
6c8dbf00 OB |
1589 | Since the lowest 2 bits in max_fast don't matter in size comparisons, |
1590 | they are used as flags. | |
1591 | */ | |
f65fd747 | 1592 | |
fa8d436c | 1593 | /* |
6c8dbf00 OB |
1594 | FASTCHUNKS_BIT held in max_fast indicates that there are probably |
1595 | some fastbin chunks. It is set true on entering a chunk into any | |
1596 | fastbin, and cleared only in malloc_consolidate. | |
f65fd747 | 1597 | |
6c8dbf00 OB |
1598 | The truth value is inverted so that have_fastchunks will be true |
1599 | upon startup (since statics are zero-filled), simplifying | |
1600 | initialization checks. | |
1601 | */ | |
f65fd747 | 1602 | |
fa8d436c | 1603 | #define FASTCHUNKS_BIT (1U) |
f65fd747 | 1604 | |
6c8dbf00 | 1605 | #define have_fastchunks(M) (((M)->flags & FASTCHUNKS_BIT) == 0) |
425ce2ed UD |
1606 | #define clear_fastchunks(M) catomic_or (&(M)->flags, FASTCHUNKS_BIT) |
1607 | #define set_fastchunks(M) catomic_and (&(M)->flags, ~FASTCHUNKS_BIT) | |
f65fd747 UD |
1608 | |
1609 | /* | |
6c8dbf00 OB |
1610 | NONCONTIGUOUS_BIT indicates that MORECORE does not return contiguous |
1611 | regions. Otherwise, contiguity is exploited in merging together, | |
1612 | when possible, results from consecutive MORECORE calls. | |
f65fd747 | 1613 | |
6c8dbf00 OB |
1614 | The initial value comes from MORECORE_CONTIGUOUS, but is |
1615 | changed dynamically if mmap is ever used as an sbrk substitute. | |
1616 | */ | |
f65fd747 | 1617 | |
fa8d436c | 1618 | #define NONCONTIGUOUS_BIT (2U) |
f65fd747 | 1619 | |
6c8dbf00 OB |
1620 | #define contiguous(M) (((M)->flags & NONCONTIGUOUS_BIT) == 0) |
1621 | #define noncontiguous(M) (((M)->flags & NONCONTIGUOUS_BIT) != 0) | |
1622 | #define set_noncontiguous(M) ((M)->flags |= NONCONTIGUOUS_BIT) | |
9bf248c6 | 1623 | #define set_contiguous(M) ((M)->flags &= ~NONCONTIGUOUS_BIT) |
f65fd747 | 1624 | |
fff94fa2 SP |
1625 | /* ARENA_CORRUPTION_BIT is set if a memory corruption was detected on the |
1626 | arena. Such an arena is no longer used to allocate chunks. Chunks | |
1627 | allocated in that arena before detecting corruption are not freed. */ | |
1628 | ||
1629 | #define ARENA_CORRUPTION_BIT (4U) | |
1630 | ||
1631 | #define arena_is_corrupt(A) (((A)->flags & ARENA_CORRUPTION_BIT)) | |
1632 | #define set_arena_corrupt(A) ((A)->flags |= ARENA_CORRUPTION_BIT) | |
1633 | ||
a9177ff5 RM |
1634 | /* |
1635 | Set value of max_fast. | |
fa8d436c UD |
1636 | Use impossibly small value if 0. |
1637 | Precondition: there are no existing fastbin chunks. | |
1638 | Setting the value clears fastchunk bit but preserves noncontiguous bit. | |
6c8dbf00 | 1639 | */ |
f65fd747 | 1640 | |
9bf248c6 | 1641 | #define set_max_fast(s) \ |
991eda1e | 1642 | global_max_fast = (((s) == 0) \ |
6c8dbf00 | 1643 | ? SMALLBIN_WIDTH : ((s + SIZE_SZ) & ~MALLOC_ALIGN_MASK)) |
9bf248c6 | 1644 | #define get_max_fast() global_max_fast |
f65fd747 | 1645 | |
f65fd747 UD |
1646 | |
1647 | /* | |
fa8d436c | 1648 | ----------- Internal state representation and initialization ----------- |
6c8dbf00 | 1649 | */ |
f65fd747 | 1650 | |
6c8dbf00 OB |
1651 | struct malloc_state |
1652 | { | |
fa8d436c | 1653 | /* Serialize access. */ |
cbb47fa1 | 1654 | __libc_lock_define (, mutex); |
9bf248c6 UD |
1655 | |
1656 | /* Flags (formerly in max_fast). */ | |
1657 | int flags; | |
f65fd747 | 1658 | |
fa8d436c | 1659 | /* Fastbins */ |
6c8dbf00 | 1660 | mfastbinptr fastbinsY[NFASTBINS]; |
f65fd747 | 1661 | |
fa8d436c | 1662 | /* Base of the topmost chunk -- not otherwise kept in a bin */ |
6c8dbf00 | 1663 | mchunkptr top; |
f65fd747 | 1664 | |
fa8d436c | 1665 | /* The remainder from the most recent split of a small request */ |
6c8dbf00 | 1666 | mchunkptr last_remainder; |
f65fd747 | 1667 | |
fa8d436c | 1668 | /* Normal bins packed as described above */ |
6c8dbf00 | 1669 | mchunkptr bins[NBINS * 2 - 2]; |
f65fd747 | 1670 | |
fa8d436c | 1671 | /* Bitmap of bins */ |
6c8dbf00 | 1672 | unsigned int binmap[BINMAPSIZE]; |
f65fd747 | 1673 | |
fa8d436c UD |
1674 | /* Linked list */ |
1675 | struct malloc_state *next; | |
f65fd747 | 1676 | |
a62719ba | 1677 | /* Linked list for free arenas. Access to this field is serialized |
90c400bd | 1678 | by free_list_lock in arena.c. */ |
425ce2ed | 1679 | struct malloc_state *next_free; |
425ce2ed | 1680 | |
a62719ba | 1681 | /* Number of threads attached to this arena. 0 if the arena is on |
90c400bd FW |
1682 | the free list. Access to this field is serialized by |
1683 | free_list_lock in arena.c. */ | |
a62719ba FW |
1684 | INTERNAL_SIZE_T attached_threads; |
1685 | ||
fa8d436c UD |
1686 | /* Memory allocated from the system in this arena. */ |
1687 | INTERNAL_SIZE_T system_mem; | |
1688 | INTERNAL_SIZE_T max_system_mem; | |
1689 | }; | |
f65fd747 | 1690 | |
6c8dbf00 OB |
1691 | struct malloc_par |
1692 | { | |
fa8d436c | 1693 | /* Tunable parameters */ |
6c8dbf00 OB |
1694 | unsigned long trim_threshold; |
1695 | INTERNAL_SIZE_T top_pad; | |
1696 | INTERNAL_SIZE_T mmap_threshold; | |
1697 | INTERNAL_SIZE_T arena_test; | |
1698 | INTERNAL_SIZE_T arena_max; | |
fa8d436c UD |
1699 | |
1700 | /* Memory map support */ | |
6c8dbf00 OB |
1701 | int n_mmaps; |
1702 | int n_mmaps_max; | |
1703 | int max_n_mmaps; | |
1d05c2fb UD |
1704 | /* the mmap_threshold is dynamic, until the user sets |
1705 | it manually, at which point we need to disable any | |
1706 | dynamic behavior. */ | |
6c8dbf00 | 1707 | int no_dyn_threshold; |
fa8d436c | 1708 | |
fa8d436c | 1709 | /* Statistics */ |
6c8dbf00 | 1710 | INTERNAL_SIZE_T mmapped_mem; |
6c8dbf00 | 1711 | INTERNAL_SIZE_T max_mmapped_mem; |
fa8d436c UD |
1712 | |
1713 | /* First address handed out by MORECORE/sbrk. */ | |
6c8dbf00 | 1714 | char *sbrk_base; |
fa8d436c | 1715 | }; |
f65fd747 | 1716 | |
fa8d436c UD |
1717 | /* There are several instances of this struct ("arenas") in this |
1718 | malloc. If you are adapting this malloc in a way that does NOT use | |
1719 | a static or mmapped malloc_state, you MUST explicitly zero-fill it | |
1720 | before using. This malloc relies on the property that malloc_state | |
1721 | is initialized to all zeroes (as is true of C statics). */ | |
f65fd747 | 1722 | |
02d46fc4 | 1723 | static struct malloc_state main_arena = |
6c8dbf00 | 1724 | { |
400e1226 | 1725 | .mutex = _LIBC_LOCK_INITIALIZER, |
a62719ba FW |
1726 | .next = &main_arena, |
1727 | .attached_threads = 1 | |
6c8dbf00 | 1728 | }; |
f65fd747 | 1729 | |
4cf6c72f FW |
1730 | /* These variables are used for undumping support. Chunked are marked |
1731 | as using mmap, but we leave them alone if they fall into this | |
1e8a8875 FW |
1732 | range. NB: The chunk size for these chunks only includes the |
1733 | initial size field (of SIZE_SZ bytes), there is no trailing size | |
1734 | field (unlike with regular mmapped chunks). */ | |
4cf6c72f FW |
1735 | static mchunkptr dumped_main_arena_start; /* Inclusive. */ |
1736 | static mchunkptr dumped_main_arena_end; /* Exclusive. */ | |
1737 | ||
1738 | /* True if the pointer falls into the dumped arena. Use this after | |
1739 | chunk_is_mmapped indicates a chunk is mmapped. */ | |
1740 | #define DUMPED_MAIN_ARENA_CHUNK(p) \ | |
1741 | ((p) >= dumped_main_arena_start && (p) < dumped_main_arena_end) | |
1742 | ||
fa8d436c | 1743 | /* There is only one instance of the malloc parameters. */ |
f65fd747 | 1744 | |
02d46fc4 | 1745 | static struct malloc_par mp_ = |
6c8dbf00 OB |
1746 | { |
1747 | .top_pad = DEFAULT_TOP_PAD, | |
1748 | .n_mmaps_max = DEFAULT_MMAP_MAX, | |
1749 | .mmap_threshold = DEFAULT_MMAP_THRESHOLD, | |
1750 | .trim_threshold = DEFAULT_TRIM_THRESHOLD, | |
1751 | #define NARENAS_FROM_NCORES(n) ((n) * (sizeof (long) == 4 ? 2 : 8)) | |
1752 | .arena_test = NARENAS_FROM_NCORES (1) | |
1753 | }; | |
f65fd747 | 1754 | |
9bf248c6 UD |
1755 | /* Maximum size of memory handled in fastbins. */ |
1756 | static INTERNAL_SIZE_T global_max_fast; | |
1757 | ||
fa8d436c | 1758 | /* |
6c8dbf00 | 1759 | Initialize a malloc_state struct. |
f65fd747 | 1760 | |
6c8dbf00 OB |
1761 | This is called only from within malloc_consolidate, which needs |
1762 | be called in the same contexts anyway. It is never called directly | |
1763 | outside of malloc_consolidate because some optimizing compilers try | |
1764 | to inline it at all call points, which turns out not to be an | |
1765 | optimization at all. (Inlining it in malloc_consolidate is fine though.) | |
1766 | */ | |
f65fd747 | 1767 | |
6c8dbf00 OB |
1768 | static void |
1769 | malloc_init_state (mstate av) | |
fa8d436c | 1770 | { |
6c8dbf00 | 1771 | int i; |
fa8d436c | 1772 | mbinptr bin; |
a9177ff5 | 1773 | |
fa8d436c | 1774 | /* Establish circular links for normal bins */ |
6c8dbf00 OB |
1775 | for (i = 1; i < NBINS; ++i) |
1776 | { | |
1777 | bin = bin_at (av, i); | |
1778 | bin->fd = bin->bk = bin; | |
1779 | } | |
f65fd747 | 1780 | |
fa8d436c UD |
1781 | #if MORECORE_CONTIGUOUS |
1782 | if (av != &main_arena) | |
1783 | #endif | |
6c8dbf00 | 1784 | set_noncontiguous (av); |
9bf248c6 | 1785 | if (av == &main_arena) |
6c8dbf00 | 1786 | set_max_fast (DEFAULT_MXFAST); |
9bf248c6 | 1787 | av->flags |= FASTCHUNKS_BIT; |
f65fd747 | 1788 | |
6c8dbf00 | 1789 | av->top = initial_top (av); |
fa8d436c | 1790 | } |
e9b3e3c5 | 1791 | |
a9177ff5 | 1792 | /* |
fa8d436c | 1793 | Other internal utilities operating on mstates |
6c8dbf00 | 1794 | */ |
f65fd747 | 1795 | |
6c8dbf00 OB |
1796 | static void *sysmalloc (INTERNAL_SIZE_T, mstate); |
1797 | static int systrim (size_t, mstate); | |
1798 | static void malloc_consolidate (mstate); | |
7e3be507 | 1799 | |
404d4cef RM |
1800 | |
1801 | /* -------------- Early definitions for debugging hooks ---------------- */ | |
1802 | ||
1803 | /* Define and initialize the hook variables. These weak definitions must | |
1804 | appear before any use of the variables in a function (arena.c uses one). */ | |
1805 | #ifndef weak_variable | |
404d4cef RM |
1806 | /* In GNU libc we want the hook variables to be weak definitions to |
1807 | avoid a problem with Emacs. */ | |
22a89187 | 1808 | # define weak_variable weak_function |
404d4cef RM |
1809 | #endif |
1810 | ||
1811 | /* Forward declarations. */ | |
6c8dbf00 OB |
1812 | static void *malloc_hook_ini (size_t sz, |
1813 | const void *caller) __THROW; | |
1814 | static void *realloc_hook_ini (void *ptr, size_t sz, | |
1815 | const void *caller) __THROW; | |
1816 | static void *memalign_hook_ini (size_t alignment, size_t sz, | |
1817 | const void *caller) __THROW; | |
404d4cef | 1818 | |
2ba3cfa1 | 1819 | #if HAVE_MALLOC_INIT_HOOK |
92e1ab0e FW |
1820 | void weak_variable (*__malloc_initialize_hook) (void) = NULL; |
1821 | compat_symbol (libc, __malloc_initialize_hook, | |
1822 | __malloc_initialize_hook, GLIBC_2_0); | |
2ba3cfa1 FW |
1823 | #endif |
1824 | ||
a222d91a | 1825 | void weak_variable (*__free_hook) (void *__ptr, |
6c8dbf00 | 1826 | const void *) = NULL; |
a222d91a | 1827 | void *weak_variable (*__malloc_hook) |
6c8dbf00 | 1828 | (size_t __size, const void *) = malloc_hook_ini; |
a222d91a | 1829 | void *weak_variable (*__realloc_hook) |
6c8dbf00 OB |
1830 | (void *__ptr, size_t __size, const void *) |
1831 | = realloc_hook_ini; | |
a222d91a | 1832 | void *weak_variable (*__memalign_hook) |
6c8dbf00 OB |
1833 | (size_t __alignment, size_t __size, const void *) |
1834 | = memalign_hook_ini; | |
06d6611a | 1835 | void weak_variable (*__after_morecore_hook) (void) = NULL; |
404d4cef RM |
1836 | |
1837 | ||
3e030bd5 UD |
1838 | /* ---------------- Error behavior ------------------------------------ */ |
1839 | ||
1840 | #ifndef DEFAULT_CHECK_ACTION | |
6c8dbf00 | 1841 | # define DEFAULT_CHECK_ACTION 3 |
3e030bd5 UD |
1842 | #endif |
1843 | ||
1844 | static int check_action = DEFAULT_CHECK_ACTION; | |
1845 | ||
1846 | ||
854278df UD |
1847 | /* ------------------ Testing support ----------------------------------*/ |
1848 | ||
1849 | static int perturb_byte; | |
1850 | ||
af102d95 | 1851 | static void |
e8349efd OB |
1852 | alloc_perturb (char *p, size_t n) |
1853 | { | |
1854 | if (__glibc_unlikely (perturb_byte)) | |
1855 | memset (p, perturb_byte ^ 0xff, n); | |
1856 | } | |
1857 | ||
af102d95 | 1858 | static void |
e8349efd OB |
1859 | free_perturb (char *p, size_t n) |
1860 | { | |
1861 | if (__glibc_unlikely (perturb_byte)) | |
1862 | memset (p, perturb_byte, n); | |
1863 | } | |
1864 | ||
854278df UD |
1865 | |
1866 | ||
3ea5be54 AO |
1867 | #include <stap-probe.h> |
1868 | ||
fa8d436c UD |
1869 | /* ------------------- Support for multiple arenas -------------------- */ |
1870 | #include "arena.c" | |
f65fd747 | 1871 | |
fa8d436c | 1872 | /* |
6c8dbf00 | 1873 | Debugging support |
f65fd747 | 1874 | |
6c8dbf00 OB |
1875 | These routines make a number of assertions about the states |
1876 | of data structures that should be true at all times. If any | |
1877 | are not true, it's very likely that a user program has somehow | |
1878 | trashed memory. (It's also possible that there is a coding error | |
1879 | in malloc. In which case, please report it!) | |
1880 | */ | |
ee74a442 | 1881 | |
6c8dbf00 | 1882 | #if !MALLOC_DEBUG |
d8f00d46 | 1883 | |
6c8dbf00 OB |
1884 | # define check_chunk(A, P) |
1885 | # define check_free_chunk(A, P) | |
1886 | # define check_inuse_chunk(A, P) | |
1887 | # define check_remalloced_chunk(A, P, N) | |
1888 | # define check_malloced_chunk(A, P, N) | |
1889 | # define check_malloc_state(A) | |
d8f00d46 | 1890 | |
fa8d436c | 1891 | #else |
ca34d7a7 | 1892 | |
6c8dbf00 OB |
1893 | # define check_chunk(A, P) do_check_chunk (A, P) |
1894 | # define check_free_chunk(A, P) do_check_free_chunk (A, P) | |
1895 | # define check_inuse_chunk(A, P) do_check_inuse_chunk (A, P) | |
1896 | # define check_remalloced_chunk(A, P, N) do_check_remalloced_chunk (A, P, N) | |
1897 | # define check_malloced_chunk(A, P, N) do_check_malloced_chunk (A, P, N) | |
1898 | # define check_malloc_state(A) do_check_malloc_state (A) | |
ca34d7a7 | 1899 | |
fa8d436c | 1900 | /* |
6c8dbf00 OB |
1901 | Properties of all chunks |
1902 | */ | |
ca34d7a7 | 1903 | |
6c8dbf00 OB |
1904 | static void |
1905 | do_check_chunk (mstate av, mchunkptr p) | |
ca34d7a7 | 1906 | { |
6c8dbf00 | 1907 | unsigned long sz = chunksize (p); |
fa8d436c | 1908 | /* min and max possible addresses assuming contiguous allocation */ |
6c8dbf00 OB |
1909 | char *max_address = (char *) (av->top) + chunksize (av->top); |
1910 | char *min_address = max_address - av->system_mem; | |
fa8d436c | 1911 | |
6c8dbf00 OB |
1912 | if (!chunk_is_mmapped (p)) |
1913 | { | |
1914 | /* Has legal address ... */ | |
1915 | if (p != av->top) | |
1916 | { | |
1917 | if (contiguous (av)) | |
1918 | { | |
1919 | assert (((char *) p) >= min_address); | |
1920 | assert (((char *) p + sz) <= ((char *) (av->top))); | |
1921 | } | |
1922 | } | |
1923 | else | |
1924 | { | |
1925 | /* top size is always at least MINSIZE */ | |
1926 | assert ((unsigned long) (sz) >= MINSIZE); | |
1927 | /* top predecessor always marked inuse */ | |
1928 | assert (prev_inuse (p)); | |
1929 | } | |
fa8d436c | 1930 | } |
4cf6c72f | 1931 | else if (!DUMPED_MAIN_ARENA_CHUNK (p)) |
6c8dbf00 OB |
1932 | { |
1933 | /* address is outside main heap */ | |
1934 | if (contiguous (av) && av->top != initial_top (av)) | |
1935 | { | |
1936 | assert (((char *) p) < min_address || ((char *) p) >= max_address); | |
1937 | } | |
1938 | /* chunk is page-aligned */ | |
e9c4fe93 | 1939 | assert (((prev_size (p) + sz) & (GLRO (dl_pagesize) - 1)) == 0); |
6c8dbf00 OB |
1940 | /* mem is aligned */ |
1941 | assert (aligned_OK (chunk2mem (p))); | |
fa8d436c | 1942 | } |
eb406346 UD |
1943 | } |
1944 | ||
fa8d436c | 1945 | /* |
6c8dbf00 OB |
1946 | Properties of free chunks |
1947 | */ | |
ee74a442 | 1948 | |
6c8dbf00 OB |
1949 | static void |
1950 | do_check_free_chunk (mstate av, mchunkptr p) | |
67c94753 | 1951 | { |
6c8dbf00 OB |
1952 | INTERNAL_SIZE_T sz = p->size & ~(PREV_INUSE | NON_MAIN_ARENA); |
1953 | mchunkptr next = chunk_at_offset (p, sz); | |
67c94753 | 1954 | |
6c8dbf00 | 1955 | do_check_chunk (av, p); |
67c94753 | 1956 | |
fa8d436c | 1957 | /* Chunk must claim to be free ... */ |
6c8dbf00 OB |
1958 | assert (!inuse (p)); |
1959 | assert (!chunk_is_mmapped (p)); | |
67c94753 | 1960 | |
fa8d436c | 1961 | /* Unless a special marker, must have OK fields */ |
6c8dbf00 OB |
1962 | if ((unsigned long) (sz) >= MINSIZE) |
1963 | { | |
1964 | assert ((sz & MALLOC_ALIGN_MASK) == 0); | |
1965 | assert (aligned_OK (chunk2mem (p))); | |
1966 | /* ... matching footer field */ | |
e9c4fe93 | 1967 | assert (prev_size (p) == sz); |
6c8dbf00 OB |
1968 | /* ... and is fully consolidated */ |
1969 | assert (prev_inuse (p)); | |
1970 | assert (next == av->top || inuse (next)); | |
1971 | ||
1972 | /* ... and has minimally sane links */ | |
1973 | assert (p->fd->bk == p); | |
1974 | assert (p->bk->fd == p); | |
1975 | } | |
fa8d436c | 1976 | else /* markers are always of size SIZE_SZ */ |
6c8dbf00 | 1977 | assert (sz == SIZE_SZ); |
67c94753 | 1978 | } |
67c94753 | 1979 | |
fa8d436c | 1980 | /* |
6c8dbf00 OB |
1981 | Properties of inuse chunks |
1982 | */ | |
fa8d436c | 1983 | |
6c8dbf00 OB |
1984 | static void |
1985 | do_check_inuse_chunk (mstate av, mchunkptr p) | |
f65fd747 | 1986 | { |
fa8d436c | 1987 | mchunkptr next; |
f65fd747 | 1988 | |
6c8dbf00 | 1989 | do_check_chunk (av, p); |
f65fd747 | 1990 | |
6c8dbf00 | 1991 | if (chunk_is_mmapped (p)) |
fa8d436c | 1992 | return; /* mmapped chunks have no next/prev */ |
ca34d7a7 | 1993 | |
fa8d436c | 1994 | /* Check whether it claims to be in use ... */ |
6c8dbf00 | 1995 | assert (inuse (p)); |
10dc2a90 | 1996 | |
6c8dbf00 | 1997 | next = next_chunk (p); |
10dc2a90 | 1998 | |
fa8d436c | 1999 | /* ... and is surrounded by OK chunks. |
6c8dbf00 OB |
2000 | Since more things can be checked with free chunks than inuse ones, |
2001 | if an inuse chunk borders them and debug is on, it's worth doing them. | |
2002 | */ | |
2003 | if (!prev_inuse (p)) | |
2004 | { | |
2005 | /* Note that we cannot even look at prev unless it is not inuse */ | |
2006 | mchunkptr prv = prev_chunk (p); | |
2007 | assert (next_chunk (prv) == p); | |
2008 | do_check_free_chunk (av, prv); | |
2009 | } | |
fa8d436c | 2010 | |
6c8dbf00 OB |
2011 | if (next == av->top) |
2012 | { | |
2013 | assert (prev_inuse (next)); | |
2014 | assert (chunksize (next) >= MINSIZE); | |
2015 | } | |
2016 | else if (!inuse (next)) | |
2017 | do_check_free_chunk (av, next); | |
10dc2a90 UD |
2018 | } |
2019 | ||
fa8d436c | 2020 | /* |
6c8dbf00 OB |
2021 | Properties of chunks recycled from fastbins |
2022 | */ | |
fa8d436c | 2023 | |
6c8dbf00 OB |
2024 | static void |
2025 | do_check_remalloced_chunk (mstate av, mchunkptr p, INTERNAL_SIZE_T s) | |
10dc2a90 | 2026 | { |
6c8dbf00 | 2027 | INTERNAL_SIZE_T sz = p->size & ~(PREV_INUSE | NON_MAIN_ARENA); |
fa8d436c | 2028 | |
6c8dbf00 OB |
2029 | if (!chunk_is_mmapped (p)) |
2030 | { | |
2031 | assert (av == arena_for_chunk (p)); | |
e9c4fe93 | 2032 | if (chunk_main_arena (p)) |
6c8dbf00 | 2033 | assert (av == &main_arena); |
e9c4fe93 FW |
2034 | else |
2035 | assert (av != &main_arena); | |
6c8dbf00 | 2036 | } |
fa8d436c | 2037 | |
6c8dbf00 | 2038 | do_check_inuse_chunk (av, p); |
fa8d436c UD |
2039 | |
2040 | /* Legal size ... */ | |
6c8dbf00 OB |
2041 | assert ((sz & MALLOC_ALIGN_MASK) == 0); |
2042 | assert ((unsigned long) (sz) >= MINSIZE); | |
fa8d436c | 2043 | /* ... and alignment */ |
6c8dbf00 | 2044 | assert (aligned_OK (chunk2mem (p))); |
fa8d436c | 2045 | /* chunk is less than MINSIZE more than request */ |
6c8dbf00 OB |
2046 | assert ((long) (sz) - (long) (s) >= 0); |
2047 | assert ((long) (sz) - (long) (s + MINSIZE) < 0); | |
10dc2a90 UD |
2048 | } |
2049 | ||
fa8d436c | 2050 | /* |
6c8dbf00 OB |
2051 | Properties of nonrecycled chunks at the point they are malloced |
2052 | */ | |
fa8d436c | 2053 | |
6c8dbf00 OB |
2054 | static void |
2055 | do_check_malloced_chunk (mstate av, mchunkptr p, INTERNAL_SIZE_T s) | |
10dc2a90 | 2056 | { |
fa8d436c | 2057 | /* same as recycled case ... */ |
6c8dbf00 | 2058 | do_check_remalloced_chunk (av, p, s); |
10dc2a90 | 2059 | |
fa8d436c | 2060 | /* |
6c8dbf00 OB |
2061 | ... plus, must obey implementation invariant that prev_inuse is |
2062 | always true of any allocated chunk; i.e., that each allocated | |
2063 | chunk borders either a previously allocated and still in-use | |
2064 | chunk, or the base of its memory arena. This is ensured | |
2065 | by making all allocations from the `lowest' part of any found | |
2066 | chunk. This does not necessarily hold however for chunks | |
2067 | recycled via fastbins. | |
2068 | */ | |
2069 | ||
2070 | assert (prev_inuse (p)); | |
fa8d436c | 2071 | } |
10dc2a90 | 2072 | |
f65fd747 | 2073 | |
fa8d436c | 2074 | /* |
6c8dbf00 | 2075 | Properties of malloc_state. |
f65fd747 | 2076 | |
6c8dbf00 OB |
2077 | This may be useful for debugging malloc, as well as detecting user |
2078 | programmer errors that somehow write into malloc_state. | |
f65fd747 | 2079 | |
6c8dbf00 OB |
2080 | If you are extending or experimenting with this malloc, you can |
2081 | probably figure out how to hack this routine to print out or | |
2082 | display chunk addresses, sizes, bins, and other instrumentation. | |
2083 | */ | |
f65fd747 | 2084 | |
6c8dbf00 OB |
2085 | static void |
2086 | do_check_malloc_state (mstate av) | |
fa8d436c UD |
2087 | { |
2088 | int i; | |
2089 | mchunkptr p; | |
2090 | mchunkptr q; | |
2091 | mbinptr b; | |
fa8d436c UD |
2092 | unsigned int idx; |
2093 | INTERNAL_SIZE_T size; | |
2094 | unsigned long total = 0; | |
2095 | int max_fast_bin; | |
f65fd747 | 2096 | |
fa8d436c | 2097 | /* internal size_t must be no wider than pointer type */ |
6c8dbf00 | 2098 | assert (sizeof (INTERNAL_SIZE_T) <= sizeof (char *)); |
f65fd747 | 2099 | |
fa8d436c | 2100 | /* alignment is a power of 2 */ |
6c8dbf00 | 2101 | assert ((MALLOC_ALIGNMENT & (MALLOC_ALIGNMENT - 1)) == 0); |
f65fd747 | 2102 | |
fa8d436c | 2103 | /* cannot run remaining checks until fully initialized */ |
6c8dbf00 | 2104 | if (av->top == 0 || av->top == initial_top (av)) |
fa8d436c | 2105 | return; |
f65fd747 | 2106 | |
fa8d436c | 2107 | /* pagesize is a power of 2 */ |
8a35c3fe | 2108 | assert (powerof2(GLRO (dl_pagesize))); |
f65fd747 | 2109 | |
fa8d436c | 2110 | /* A contiguous main_arena is consistent with sbrk_base. */ |
6c8dbf00 OB |
2111 | if (av == &main_arena && contiguous (av)) |
2112 | assert ((char *) mp_.sbrk_base + av->system_mem == | |
2113 | (char *) av->top + chunksize (av->top)); | |
fa8d436c UD |
2114 | |
2115 | /* properties of fastbins */ | |
2116 | ||
2117 | /* max_fast is in allowed range */ | |
6c8dbf00 OB |
2118 | assert ((get_max_fast () & ~1) <= request2size (MAX_FAST_SIZE)); |
2119 | ||
2120 | max_fast_bin = fastbin_index (get_max_fast ()); | |
2121 | ||
2122 | for (i = 0; i < NFASTBINS; ++i) | |
2123 | { | |
2124 | p = fastbin (av, i); | |
2125 | ||
2126 | /* The following test can only be performed for the main arena. | |
2127 | While mallopt calls malloc_consolidate to get rid of all fast | |
2128 | bins (especially those larger than the new maximum) this does | |
2129 | only happen for the main arena. Trying to do this for any | |
2130 | other arena would mean those arenas have to be locked and | |
2131 | malloc_consolidate be called for them. This is excessive. And | |
2132 | even if this is acceptable to somebody it still cannot solve | |
2133 | the problem completely since if the arena is locked a | |
2134 | concurrent malloc call might create a new arena which then | |
2135 | could use the newly invalid fast bins. */ | |
2136 | ||
2137 | /* all bins past max_fast are empty */ | |
2138 | if (av == &main_arena && i > max_fast_bin) | |
2139 | assert (p == 0); | |
2140 | ||
2141 | while (p != 0) | |
2142 | { | |
2143 | /* each chunk claims to be inuse */ | |
2144 | do_check_inuse_chunk (av, p); | |
2145 | total += chunksize (p); | |
2146 | /* chunk belongs in this bin */ | |
2147 | assert (fastbin_index (chunksize (p)) == i); | |
2148 | p = p->fd; | |
2149 | } | |
fa8d436c | 2150 | } |
fa8d436c UD |
2151 | |
2152 | if (total != 0) | |
6c8dbf00 OB |
2153 | assert (have_fastchunks (av)); |
2154 | else if (!have_fastchunks (av)) | |
2155 | assert (total == 0); | |
fa8d436c UD |
2156 | |
2157 | /* check normal bins */ | |
6c8dbf00 OB |
2158 | for (i = 1; i < NBINS; ++i) |
2159 | { | |
2160 | b = bin_at (av, i); | |
2161 | ||
2162 | /* binmap is accurate (except for bin 1 == unsorted_chunks) */ | |
2163 | if (i >= 2) | |
2164 | { | |
2165 | unsigned int binbit = get_binmap (av, i); | |
2166 | int empty = last (b) == b; | |
2167 | if (!binbit) | |
2168 | assert (empty); | |
2169 | else if (!empty) | |
2170 | assert (binbit); | |
2171 | } | |
2172 | ||
2173 | for (p = last (b); p != b; p = p->bk) | |
2174 | { | |
2175 | /* each chunk claims to be free */ | |
2176 | do_check_free_chunk (av, p); | |
2177 | size = chunksize (p); | |
2178 | total += size; | |
2179 | if (i >= 2) | |
2180 | { | |
2181 | /* chunk belongs in bin */ | |
2182 | idx = bin_index (size); | |
2183 | assert (idx == i); | |
2184 | /* lists are sorted */ | |
2185 | assert (p->bk == b || | |
2186 | (unsigned long) chunksize (p->bk) >= (unsigned long) chunksize (p)); | |
2187 | ||
2188 | if (!in_smallbin_range (size)) | |
2189 | { | |
2190 | if (p->fd_nextsize != NULL) | |
2191 | { | |
2192 | if (p->fd_nextsize == p) | |
2193 | assert (p->bk_nextsize == p); | |
2194 | else | |
2195 | { | |
2196 | if (p->fd_nextsize == first (b)) | |
2197 | assert (chunksize (p) < chunksize (p->fd_nextsize)); | |
2198 | else | |
2199 | assert (chunksize (p) > chunksize (p->fd_nextsize)); | |
2200 | ||
2201 | if (p == first (b)) | |
2202 | assert (chunksize (p) > chunksize (p->bk_nextsize)); | |
2203 | else | |
2204 | assert (chunksize (p) < chunksize (p->bk_nextsize)); | |
2205 | } | |
2206 | } | |
2207 | else | |
2208 | assert (p->bk_nextsize == NULL); | |
2209 | } | |
2210 | } | |
2211 | else if (!in_smallbin_range (size)) | |
2212 | assert (p->fd_nextsize == NULL && p->bk_nextsize == NULL); | |
2213 | /* chunk is followed by a legal chain of inuse chunks */ | |
2214 | for (q = next_chunk (p); | |
2215 | (q != av->top && inuse (q) && | |
2216 | (unsigned long) (chunksize (q)) >= MINSIZE); | |
2217 | q = next_chunk (q)) | |
2218 | do_check_inuse_chunk (av, q); | |
2219 | } | |
fa8d436c | 2220 | } |
f65fd747 | 2221 | |
fa8d436c | 2222 | /* top chunk is OK */ |
6c8dbf00 | 2223 | check_chunk (av, av->top); |
fa8d436c UD |
2224 | } |
2225 | #endif | |
2226 | ||
2227 | ||
2228 | /* ----------------- Support for debugging hooks -------------------- */ | |
2229 | #include "hooks.c" | |
2230 | ||
2231 | ||
2232 | /* ----------- Routines dealing with system allocation -------------- */ | |
2233 | ||
2234 | /* | |
6c8dbf00 OB |
2235 | sysmalloc handles malloc cases requiring more memory from the system. |
2236 | On entry, it is assumed that av->top does not have enough | |
2237 | space to service request for nb bytes, thus requiring that av->top | |
2238 | be extended or replaced. | |
2239 | */ | |
fa8d436c | 2240 | |
6c8dbf00 OB |
2241 | static void * |
2242 | sysmalloc (INTERNAL_SIZE_T nb, mstate av) | |
f65fd747 | 2243 | { |
6c8dbf00 | 2244 | mchunkptr old_top; /* incoming value of av->top */ |
fa8d436c | 2245 | INTERNAL_SIZE_T old_size; /* its size */ |
6c8dbf00 | 2246 | char *old_end; /* its end address */ |
f65fd747 | 2247 | |
6c8dbf00 OB |
2248 | long size; /* arg to first MORECORE or mmap call */ |
2249 | char *brk; /* return value from MORECORE */ | |
f65fd747 | 2250 | |
6c8dbf00 OB |
2251 | long correction; /* arg to 2nd MORECORE call */ |
2252 | char *snd_brk; /* 2nd return val */ | |
f65fd747 | 2253 | |
fa8d436c UD |
2254 | INTERNAL_SIZE_T front_misalign; /* unusable bytes at front of new space */ |
2255 | INTERNAL_SIZE_T end_misalign; /* partial page left at end of new space */ | |
6c8dbf00 | 2256 | char *aligned_brk; /* aligned offset into brk */ |
f65fd747 | 2257 | |
6c8dbf00 OB |
2258 | mchunkptr p; /* the allocated/returned chunk */ |
2259 | mchunkptr remainder; /* remainder from allocation */ | |
2260 | unsigned long remainder_size; /* its size */ | |
fa8d436c | 2261 | |
fa8d436c | 2262 | |
8a35c3fe | 2263 | size_t pagesize = GLRO (dl_pagesize); |
6c8dbf00 | 2264 | bool tried_mmap = false; |
fa8d436c UD |
2265 | |
2266 | ||
fa8d436c | 2267 | /* |
6c8dbf00 OB |
2268 | If have mmap, and the request size meets the mmap threshold, and |
2269 | the system supports mmap, and there are few enough currently | |
2270 | allocated mmapped regions, try to directly map this request | |
2271 | rather than expanding top. | |
2272 | */ | |
2273 | ||
fff94fa2 SP |
2274 | if (av == NULL |
2275 | || ((unsigned long) (nb) >= (unsigned long) (mp_.mmap_threshold) | |
2276 | && (mp_.n_mmaps < mp_.n_mmaps_max))) | |
6c8dbf00 OB |
2277 | { |
2278 | char *mm; /* return value from mmap call*/ | |
a9177ff5 | 2279 | |
6c8dbf00 OB |
2280 | try_mmap: |
2281 | /* | |
2282 | Round up size to nearest page. For mmapped chunks, the overhead | |
2283 | is one SIZE_SZ unit larger than for normal chunks, because there | |
2284 | is no following chunk whose prev_size field could be used. | |
2285 | ||
2286 | See the front_misalign handling below, for glibc there is no | |
2287 | need for further alignments unless we have have high alignment. | |
2288 | */ | |
2289 | if (MALLOC_ALIGNMENT == 2 * SIZE_SZ) | |
8a35c3fe | 2290 | size = ALIGN_UP (nb + SIZE_SZ, pagesize); |
6c8dbf00 | 2291 | else |
8a35c3fe | 2292 | size = ALIGN_UP (nb + SIZE_SZ + MALLOC_ALIGN_MASK, pagesize); |
6c8dbf00 OB |
2293 | tried_mmap = true; |
2294 | ||
2295 | /* Don't try if size wraps around 0 */ | |
2296 | if ((unsigned long) (size) > (unsigned long) (nb)) | |
2297 | { | |
2298 | mm = (char *) (MMAP (0, size, PROT_READ | PROT_WRITE, 0)); | |
2299 | ||
2300 | if (mm != MAP_FAILED) | |
2301 | { | |
2302 | /* | |
2303 | The offset to the start of the mmapped region is stored | |
2304 | in the prev_size field of the chunk. This allows us to adjust | |
2305 | returned start address to meet alignment requirements here | |
2306 | and in memalign(), and still be able to compute proper | |
2307 | address argument for later munmap in free() and realloc(). | |
2308 | */ | |
2309 | ||
2310 | if (MALLOC_ALIGNMENT == 2 * SIZE_SZ) | |
2311 | { | |
2312 | /* For glibc, chunk2mem increases the address by 2*SIZE_SZ and | |
2313 | MALLOC_ALIGN_MASK is 2*SIZE_SZ-1. Each mmap'ed area is page | |
2314 | aligned and therefore definitely MALLOC_ALIGN_MASK-aligned. */ | |
2315 | assert (((INTERNAL_SIZE_T) chunk2mem (mm) & MALLOC_ALIGN_MASK) == 0); | |
2316 | front_misalign = 0; | |
2317 | } | |
2318 | else | |
2319 | front_misalign = (INTERNAL_SIZE_T) chunk2mem (mm) & MALLOC_ALIGN_MASK; | |
2320 | if (front_misalign > 0) | |
2321 | { | |
2322 | correction = MALLOC_ALIGNMENT - front_misalign; | |
2323 | p = (mchunkptr) (mm + correction); | |
e9c4fe93 | 2324 | set_prev_size (p, correction); |
6c8dbf00 OB |
2325 | set_head (p, (size - correction) | IS_MMAPPED); |
2326 | } | |
2327 | else | |
2328 | { | |
2329 | p = (mchunkptr) mm; | |
681421f3 | 2330 | set_prev_size (p, 0); |
6c8dbf00 OB |
2331 | set_head (p, size | IS_MMAPPED); |
2332 | } | |
2333 | ||
2334 | /* update statistics */ | |
2335 | ||
2336 | int new = atomic_exchange_and_add (&mp_.n_mmaps, 1) + 1; | |
2337 | atomic_max (&mp_.max_n_mmaps, new); | |
2338 | ||
2339 | unsigned long sum; | |
2340 | sum = atomic_exchange_and_add (&mp_.mmapped_mem, size) + size; | |
2341 | atomic_max (&mp_.max_mmapped_mem, sum); | |
2342 | ||
2343 | check_chunk (av, p); | |
2344 | ||
2345 | return chunk2mem (p); | |
2346 | } | |
2347 | } | |
fa8d436c | 2348 | } |
fa8d436c | 2349 | |
fff94fa2 SP |
2350 | /* There are no usable arenas and mmap also failed. */ |
2351 | if (av == NULL) | |
2352 | return 0; | |
2353 | ||
fa8d436c UD |
2354 | /* Record incoming configuration of top */ |
2355 | ||
6c8dbf00 OB |
2356 | old_top = av->top; |
2357 | old_size = chunksize (old_top); | |
2358 | old_end = (char *) (chunk_at_offset (old_top, old_size)); | |
fa8d436c | 2359 | |
6c8dbf00 | 2360 | brk = snd_brk = (char *) (MORECORE_FAILURE); |
fa8d436c | 2361 | |
a9177ff5 | 2362 | /* |
fa8d436c UD |
2363 | If not the first time through, we require old_size to be |
2364 | at least MINSIZE and to have prev_inuse set. | |
6c8dbf00 | 2365 | */ |
fa8d436c | 2366 | |
6c8dbf00 OB |
2367 | assert ((old_top == initial_top (av) && old_size == 0) || |
2368 | ((unsigned long) (old_size) >= MINSIZE && | |
2369 | prev_inuse (old_top) && | |
8a35c3fe | 2370 | ((unsigned long) old_end & (pagesize - 1)) == 0)); |
fa8d436c UD |
2371 | |
2372 | /* Precondition: not enough current space to satisfy nb request */ | |
6c8dbf00 | 2373 | assert ((unsigned long) (old_size) < (unsigned long) (nb + MINSIZE)); |
a9177ff5 | 2374 | |
72f90263 | 2375 | |
6c8dbf00 OB |
2376 | if (av != &main_arena) |
2377 | { | |
2378 | heap_info *old_heap, *heap; | |
2379 | size_t old_heap_size; | |
2380 | ||
2381 | /* First try to extend the current heap. */ | |
2382 | old_heap = heap_for_ptr (old_top); | |
2383 | old_heap_size = old_heap->size; | |
2384 | if ((long) (MINSIZE + nb - old_size) > 0 | |
2385 | && grow_heap (old_heap, MINSIZE + nb - old_size) == 0) | |
2386 | { | |
2387 | av->system_mem += old_heap->size - old_heap_size; | |
6c8dbf00 OB |
2388 | set_head (old_top, (((char *) old_heap + old_heap->size) - (char *) old_top) |
2389 | | PREV_INUSE); | |
2390 | } | |
2391 | else if ((heap = new_heap (nb + (MINSIZE + sizeof (*heap)), mp_.top_pad))) | |
2392 | { | |
2393 | /* Use a newly allocated heap. */ | |
2394 | heap->ar_ptr = av; | |
2395 | heap->prev = old_heap; | |
2396 | av->system_mem += heap->size; | |
6c8dbf00 OB |
2397 | /* Set up the new top. */ |
2398 | top (av) = chunk_at_offset (heap, sizeof (*heap)); | |
2399 | set_head (top (av), (heap->size - sizeof (*heap)) | PREV_INUSE); | |
2400 | ||
2401 | /* Setup fencepost and free the old top chunk with a multiple of | |
2402 | MALLOC_ALIGNMENT in size. */ | |
2403 | /* The fencepost takes at least MINSIZE bytes, because it might | |
2404 | become the top chunk again later. Note that a footer is set | |
2405 | up, too, although the chunk is marked in use. */ | |
2406 | old_size = (old_size - MINSIZE) & ~MALLOC_ALIGN_MASK; | |
2407 | set_head (chunk_at_offset (old_top, old_size + 2 * SIZE_SZ), 0 | PREV_INUSE); | |
2408 | if (old_size >= MINSIZE) | |
2409 | { | |
2410 | set_head (chunk_at_offset (old_top, old_size), (2 * SIZE_SZ) | PREV_INUSE); | |
2411 | set_foot (chunk_at_offset (old_top, old_size), (2 * SIZE_SZ)); | |
2412 | set_head (old_top, old_size | PREV_INUSE | NON_MAIN_ARENA); | |
2413 | _int_free (av, old_top, 1); | |
2414 | } | |
2415 | else | |
2416 | { | |
2417 | set_head (old_top, (old_size + 2 * SIZE_SZ) | PREV_INUSE); | |
2418 | set_foot (old_top, (old_size + 2 * SIZE_SZ)); | |
2419 | } | |
2420 | } | |
2421 | else if (!tried_mmap) | |
2422 | /* We can at least try to use to mmap memory. */ | |
2423 | goto try_mmap; | |
fa8d436c | 2424 | } |
6c8dbf00 | 2425 | else /* av == main_arena */ |
fa8d436c | 2426 | |
fa8d436c | 2427 | |
6c8dbf00 OB |
2428 | { /* Request enough space for nb + pad + overhead */ |
2429 | size = nb + mp_.top_pad + MINSIZE; | |
a9177ff5 | 2430 | |
6c8dbf00 OB |
2431 | /* |
2432 | If contiguous, we can subtract out existing space that we hope to | |
2433 | combine with new space. We add it back later only if | |
2434 | we don't actually get contiguous space. | |
2435 | */ | |
a9177ff5 | 2436 | |
6c8dbf00 OB |
2437 | if (contiguous (av)) |
2438 | size -= old_size; | |
fa8d436c | 2439 | |
6c8dbf00 OB |
2440 | /* |
2441 | Round to a multiple of page size. | |
2442 | If MORECORE is not contiguous, this ensures that we only call it | |
2443 | with whole-page arguments. And if MORECORE is contiguous and | |
2444 | this is not first time through, this preserves page-alignment of | |
2445 | previous calls. Otherwise, we correct to page-align below. | |
2446 | */ | |
fa8d436c | 2447 | |
8a35c3fe | 2448 | size = ALIGN_UP (size, pagesize); |
fa8d436c | 2449 | |
6c8dbf00 OB |
2450 | /* |
2451 | Don't try to call MORECORE if argument is so big as to appear | |
2452 | negative. Note that since mmap takes size_t arg, it may succeed | |
2453 | below even if we cannot call MORECORE. | |
2454 | */ | |
2455 | ||
2456 | if (size > 0) | |
2457 | { | |
2458 | brk = (char *) (MORECORE (size)); | |
2459 | LIBC_PROBE (memory_sbrk_more, 2, brk, size); | |
2460 | } | |
2461 | ||
2462 | if (brk != (char *) (MORECORE_FAILURE)) | |
2463 | { | |
2464 | /* Call the `morecore' hook if necessary. */ | |
2465 | void (*hook) (void) = atomic_forced_read (__after_morecore_hook); | |
2466 | if (__builtin_expect (hook != NULL, 0)) | |
2467 | (*hook)(); | |
2468 | } | |
2469 | else | |
2470 | { | |
2471 | /* | |
2472 | If have mmap, try using it as a backup when MORECORE fails or | |
2473 | cannot be used. This is worth doing on systems that have "holes" in | |
2474 | address space, so sbrk cannot extend to give contiguous space, but | |
2475 | space is available elsewhere. Note that we ignore mmap max count | |
2476 | and threshold limits, since the space will not be used as a | |
2477 | segregated mmap region. | |
2478 | */ | |
2479 | ||
2480 | /* Cannot merge with old top, so add its size back in */ | |
2481 | if (contiguous (av)) | |
8a35c3fe | 2482 | size = ALIGN_UP (size + old_size, pagesize); |
6c8dbf00 OB |
2483 | |
2484 | /* If we are relying on mmap as backup, then use larger units */ | |
2485 | if ((unsigned long) (size) < (unsigned long) (MMAP_AS_MORECORE_SIZE)) | |
2486 | size = MMAP_AS_MORECORE_SIZE; | |
2487 | ||
2488 | /* Don't try if size wraps around 0 */ | |
2489 | if ((unsigned long) (size) > (unsigned long) (nb)) | |
2490 | { | |
2491 | char *mbrk = (char *) (MMAP (0, size, PROT_READ | PROT_WRITE, 0)); | |
2492 | ||
2493 | if (mbrk != MAP_FAILED) | |
2494 | { | |
2495 | /* We do not need, and cannot use, another sbrk call to find end */ | |
2496 | brk = mbrk; | |
2497 | snd_brk = brk + size; | |
2498 | ||
2499 | /* | |
2500 | Record that we no longer have a contiguous sbrk region. | |
2501 | After the first time mmap is used as backup, we do not | |
2502 | ever rely on contiguous space since this could incorrectly | |
2503 | bridge regions. | |
2504 | */ | |
2505 | set_noncontiguous (av); | |
2506 | } | |
2507 | } | |
2508 | } | |
2509 | ||
2510 | if (brk != (char *) (MORECORE_FAILURE)) | |
2511 | { | |
2512 | if (mp_.sbrk_base == 0) | |
2513 | mp_.sbrk_base = brk; | |
2514 | av->system_mem += size; | |
2515 | ||
2516 | /* | |
2517 | If MORECORE extends previous space, we can likewise extend top size. | |
2518 | */ | |
2519 | ||
2520 | if (brk == old_end && snd_brk == (char *) (MORECORE_FAILURE)) | |
2521 | set_head (old_top, (size + old_size) | PREV_INUSE); | |
2522 | ||
2523 | else if (contiguous (av) && old_size && brk < old_end) | |
2524 | { | |
2525 | /* Oops! Someone else killed our space.. Can't touch anything. */ | |
fff94fa2 SP |
2526 | malloc_printerr (3, "break adjusted to free malloc space", brk, |
2527 | av); | |
6c8dbf00 OB |
2528 | } |
2529 | ||
2530 | /* | |
2531 | Otherwise, make adjustments: | |
2532 | ||
2533 | * If the first time through or noncontiguous, we need to call sbrk | |
2534 | just to find out where the end of memory lies. | |
2535 | ||
2536 | * We need to ensure that all returned chunks from malloc will meet | |
2537 | MALLOC_ALIGNMENT | |
2538 | ||
2539 | * If there was an intervening foreign sbrk, we need to adjust sbrk | |
2540 | request size to account for fact that we will not be able to | |
2541 | combine new space with existing space in old_top. | |
2542 | ||
2543 | * Almost all systems internally allocate whole pages at a time, in | |
2544 | which case we might as well use the whole last page of request. | |
2545 | So we allocate enough more memory to hit a page boundary now, | |
2546 | which in turn causes future contiguous calls to page-align. | |
2547 | */ | |
2548 | ||
2549 | else | |
2550 | { | |
2551 | front_misalign = 0; | |
2552 | end_misalign = 0; | |
2553 | correction = 0; | |
2554 | aligned_brk = brk; | |
2555 | ||
2556 | /* handle contiguous cases */ | |
2557 | if (contiguous (av)) | |
2558 | { | |
2559 | /* Count foreign sbrk as system_mem. */ | |
2560 | if (old_size) | |
2561 | av->system_mem += brk - old_end; | |
2562 | ||
2563 | /* Guarantee alignment of first new chunk made from this space */ | |
2564 | ||
2565 | front_misalign = (INTERNAL_SIZE_T) chunk2mem (brk) & MALLOC_ALIGN_MASK; | |
2566 | if (front_misalign > 0) | |
2567 | { | |
2568 | /* | |
2569 | Skip over some bytes to arrive at an aligned position. | |
2570 | We don't need to specially mark these wasted front bytes. | |
2571 | They will never be accessed anyway because | |
2572 | prev_inuse of av->top (and any chunk created from its start) | |
2573 | is always true after initialization. | |
2574 | */ | |
2575 | ||
2576 | correction = MALLOC_ALIGNMENT - front_misalign; | |
2577 | aligned_brk += correction; | |
2578 | } | |
2579 | ||
2580 | /* | |
2581 | If this isn't adjacent to existing space, then we will not | |
2582 | be able to merge with old_top space, so must add to 2nd request. | |
2583 | */ | |
2584 | ||
2585 | correction += old_size; | |
2586 | ||
2587 | /* Extend the end address to hit a page boundary */ | |
2588 | end_misalign = (INTERNAL_SIZE_T) (brk + size + correction); | |
8a35c3fe | 2589 | correction += (ALIGN_UP (end_misalign, pagesize)) - end_misalign; |
6c8dbf00 OB |
2590 | |
2591 | assert (correction >= 0); | |
2592 | snd_brk = (char *) (MORECORE (correction)); | |
2593 | ||
2594 | /* | |
2595 | If can't allocate correction, try to at least find out current | |
2596 | brk. It might be enough to proceed without failing. | |
2597 | ||
2598 | Note that if second sbrk did NOT fail, we assume that space | |
2599 | is contiguous with first sbrk. This is a safe assumption unless | |
2600 | program is multithreaded but doesn't use locks and a foreign sbrk | |
2601 | occurred between our first and second calls. | |
2602 | */ | |
2603 | ||
2604 | if (snd_brk == (char *) (MORECORE_FAILURE)) | |
2605 | { | |
2606 | correction = 0; | |
2607 | snd_brk = (char *) (MORECORE (0)); | |
2608 | } | |
2609 | else | |
2610 | { | |
2611 | /* Call the `morecore' hook if necessary. */ | |
2612 | void (*hook) (void) = atomic_forced_read (__after_morecore_hook); | |
2613 | if (__builtin_expect (hook != NULL, 0)) | |
2614 | (*hook)(); | |
2615 | } | |
2616 | } | |
2617 | ||
2618 | /* handle non-contiguous cases */ | |
2619 | else | |
2620 | { | |
2621 | if (MALLOC_ALIGNMENT == 2 * SIZE_SZ) | |
2622 | /* MORECORE/mmap must correctly align */ | |
2623 | assert (((unsigned long) chunk2mem (brk) & MALLOC_ALIGN_MASK) == 0); | |
2624 | else | |
2625 | { | |
2626 | front_misalign = (INTERNAL_SIZE_T) chunk2mem (brk) & MALLOC_ALIGN_MASK; | |
2627 | if (front_misalign > 0) | |
2628 | { | |
2629 | /* | |
2630 | Skip over some bytes to arrive at an aligned position. | |
2631 | We don't need to specially mark these wasted front bytes. | |
2632 | They will never be accessed anyway because | |
2633 | prev_inuse of av->top (and any chunk created from its start) | |
2634 | is always true after initialization. | |
2635 | */ | |
2636 | ||
2637 | aligned_brk += MALLOC_ALIGNMENT - front_misalign; | |
2638 | } | |
2639 | } | |
2640 | ||
2641 | /* Find out current end of memory */ | |
2642 | if (snd_brk == (char *) (MORECORE_FAILURE)) | |
2643 | { | |
2644 | snd_brk = (char *) (MORECORE (0)); | |
2645 | } | |
2646 | } | |
2647 | ||
2648 | /* Adjust top based on results of second sbrk */ | |
2649 | if (snd_brk != (char *) (MORECORE_FAILURE)) | |
2650 | { | |
2651 | av->top = (mchunkptr) aligned_brk; | |
2652 | set_head (av->top, (snd_brk - aligned_brk + correction) | PREV_INUSE); | |
2653 | av->system_mem += correction; | |
2654 | ||
2655 | /* | |
2656 | If not the first time through, we either have a | |
2657 | gap due to foreign sbrk or a non-contiguous region. Insert a | |
2658 | double fencepost at old_top to prevent consolidation with space | |
2659 | we don't own. These fenceposts are artificial chunks that are | |
2660 | marked as inuse and are in any case too small to use. We need | |
2661 | two to make sizes and alignments work out. | |
2662 | */ | |
2663 | ||
2664 | if (old_size != 0) | |
2665 | { | |
2666 | /* | |
2667 | Shrink old_top to insert fenceposts, keeping size a | |
2668 | multiple of MALLOC_ALIGNMENT. We know there is at least | |
2669 | enough space in old_top to do this. | |
2670 | */ | |
2671 | old_size = (old_size - 4 * SIZE_SZ) & ~MALLOC_ALIGN_MASK; | |
2672 | set_head (old_top, old_size | PREV_INUSE); | |
2673 | ||
2674 | /* | |
2675 | Note that the following assignments completely overwrite | |
2676 | old_top when old_size was previously MINSIZE. This is | |
2677 | intentional. We need the fencepost, even if old_top otherwise gets | |
2678 | lost. | |
2679 | */ | |
e9c4fe93 FW |
2680 | set_head (chunk_at_offset (old_top, old_size), |
2681 | (2 * SIZE_SZ) | PREV_INUSE); | |
2682 | set_head (chunk_at_offset (old_top, old_size + 2 * SIZE_SZ), | |
2683 | (2 * SIZE_SZ) | PREV_INUSE); | |
6c8dbf00 OB |
2684 | |
2685 | /* If possible, release the rest. */ | |
2686 | if (old_size >= MINSIZE) | |
2687 | { | |
2688 | _int_free (av, old_top, 1); | |
2689 | } | |
2690 | } | |
2691 | } | |
2692 | } | |
2693 | } | |
2694 | } /* if (av != &main_arena) */ | |
2695 | ||
2696 | if ((unsigned long) av->system_mem > (unsigned long) (av->max_system_mem)) | |
fa8d436c | 2697 | av->max_system_mem = av->system_mem; |
6c8dbf00 | 2698 | check_malloc_state (av); |
a9177ff5 | 2699 | |
fa8d436c UD |
2700 | /* finally, do the allocation */ |
2701 | p = av->top; | |
6c8dbf00 | 2702 | size = chunksize (p); |
fa8d436c UD |
2703 | |
2704 | /* check that one of the above allocation paths succeeded */ | |
6c8dbf00 OB |
2705 | if ((unsigned long) (size) >= (unsigned long) (nb + MINSIZE)) |
2706 | { | |
2707 | remainder_size = size - nb; | |
2708 | remainder = chunk_at_offset (p, nb); | |
2709 | av->top = remainder; | |
2710 | set_head (p, nb | PREV_INUSE | (av != &main_arena ? NON_MAIN_ARENA : 0)); | |
2711 | set_head (remainder, remainder_size | PREV_INUSE); | |
2712 | check_malloced_chunk (av, p, nb); | |
2713 | return chunk2mem (p); | |
2714 | } | |
fa8d436c UD |
2715 | |
2716 | /* catch all failure paths */ | |
8e58439c | 2717 | __set_errno (ENOMEM); |
fa8d436c UD |
2718 | return 0; |
2719 | } | |
2720 | ||
2721 | ||
2722 | /* | |
6c8dbf00 OB |
2723 | systrim is an inverse of sorts to sysmalloc. It gives memory back |
2724 | to the system (via negative arguments to sbrk) if there is unused | |
2725 | memory at the `high' end of the malloc pool. It is called | |
2726 | automatically by free() when top space exceeds the trim | |
2727 | threshold. It is also called by the public malloc_trim routine. It | |
2728 | returns 1 if it actually released any memory, else 0. | |
2729 | */ | |
fa8d436c | 2730 | |
6c8dbf00 OB |
2731 | static int |
2732 | systrim (size_t pad, mstate av) | |
fa8d436c | 2733 | { |
6c8dbf00 OB |
2734 | long top_size; /* Amount of top-most memory */ |
2735 | long extra; /* Amount to release */ | |
2736 | long released; /* Amount actually released */ | |
2737 | char *current_brk; /* address returned by pre-check sbrk call */ | |
2738 | char *new_brk; /* address returned by post-check sbrk call */ | |
8a35c3fe | 2739 | size_t pagesize; |
6c8dbf00 | 2740 | long top_area; |
fa8d436c | 2741 | |
8a35c3fe | 2742 | pagesize = GLRO (dl_pagesize); |
6c8dbf00 | 2743 | top_size = chunksize (av->top); |
a9177ff5 | 2744 | |
4b5b548c FS |
2745 | top_area = top_size - MINSIZE - 1; |
2746 | if (top_area <= pad) | |
2747 | return 0; | |
2748 | ||
ca6be165 CD |
2749 | /* Release in pagesize units and round down to the nearest page. */ |
2750 | extra = ALIGN_DOWN(top_area - pad, pagesize); | |
a9177ff5 | 2751 | |
51a7380b WN |
2752 | if (extra == 0) |
2753 | return 0; | |
2754 | ||
4b5b548c | 2755 | /* |
6c8dbf00 OB |
2756 | Only proceed if end of memory is where we last set it. |
2757 | This avoids problems if there were foreign sbrk calls. | |
2758 | */ | |
2759 | current_brk = (char *) (MORECORE (0)); | |
2760 | if (current_brk == (char *) (av->top) + top_size) | |
2761 | { | |
2762 | /* | |
2763 | Attempt to release memory. We ignore MORECORE return value, | |
2764 | and instead call again to find out where new end of memory is. | |
2765 | This avoids problems if first call releases less than we asked, | |
2766 | of if failure somehow altered brk value. (We could still | |
2767 | encounter problems if it altered brk in some very bad way, | |
2768 | but the only thing we can do is adjust anyway, which will cause | |
2769 | some downstream failure.) | |
2770 | */ | |
2771 | ||
2772 | MORECORE (-extra); | |
2773 | /* Call the `morecore' hook if necessary. */ | |
2774 | void (*hook) (void) = atomic_forced_read (__after_morecore_hook); | |
2775 | if (__builtin_expect (hook != NULL, 0)) | |
2776 | (*hook)(); | |
2777 | new_brk = (char *) (MORECORE (0)); | |
2778 | ||
2779 | LIBC_PROBE (memory_sbrk_less, 2, new_brk, extra); | |
2780 | ||
2781 | if (new_brk != (char *) MORECORE_FAILURE) | |
2782 | { | |
2783 | released = (long) (current_brk - new_brk); | |
2784 | ||
2785 | if (released != 0) | |
2786 | { | |
2787 | /* Success. Adjust top. */ | |
2788 | av->system_mem -= released; | |
2789 | set_head (av->top, (top_size - released) | PREV_INUSE); | |
2790 | check_malloc_state (av); | |
2791 | return 1; | |
2792 | } | |
2793 | } | |
fa8d436c | 2794 | } |
fa8d436c | 2795 | return 0; |
f65fd747 UD |
2796 | } |
2797 | ||
431c33c0 UD |
2798 | static void |
2799 | internal_function | |
6c8dbf00 | 2800 | munmap_chunk (mchunkptr p) |
f65fd747 | 2801 | { |
6c8dbf00 | 2802 | INTERNAL_SIZE_T size = chunksize (p); |
f65fd747 | 2803 | |
6c8dbf00 | 2804 | assert (chunk_is_mmapped (p)); |
8e635611 | 2805 | |
4cf6c72f FW |
2806 | /* Do nothing if the chunk is a faked mmapped chunk in the dumped |
2807 | main arena. We never free this memory. */ | |
2808 | if (DUMPED_MAIN_ARENA_CHUNK (p)) | |
2809 | return; | |
2810 | ||
e9c4fe93 FW |
2811 | uintptr_t block = (uintptr_t) p - prev_size (p); |
2812 | size_t total_size = prev_size (p) + size; | |
8e635611 UD |
2813 | /* Unfortunately we have to do the compilers job by hand here. Normally |
2814 | we would test BLOCK and TOTAL-SIZE separately for compliance with the | |
2815 | page size. But gcc does not recognize the optimization possibility | |
2816 | (in the moment at least) so we combine the two values into one before | |
2817 | the bit test. */ | |
6c8dbf00 | 2818 | if (__builtin_expect (((block | total_size) & (GLRO (dl_pagesize) - 1)) != 0, 0)) |
8e635611 UD |
2819 | { |
2820 | malloc_printerr (check_action, "munmap_chunk(): invalid pointer", | |
fff94fa2 | 2821 | chunk2mem (p), NULL); |
8e635611 UD |
2822 | return; |
2823 | } | |
f65fd747 | 2824 | |
c6e4925d OB |
2825 | atomic_decrement (&mp_.n_mmaps); |
2826 | atomic_add (&mp_.mmapped_mem, -total_size); | |
f65fd747 | 2827 | |
6ef76f3b UD |
2828 | /* If munmap failed the process virtual memory address space is in a |
2829 | bad shape. Just leave the block hanging around, the process will | |
2830 | terminate shortly anyway since not much can be done. */ | |
6c8dbf00 | 2831 | __munmap ((char *) block, total_size); |
f65fd747 UD |
2832 | } |
2833 | ||
2834 | #if HAVE_MREMAP | |
2835 | ||
431c33c0 UD |
2836 | static mchunkptr |
2837 | internal_function | |
6c8dbf00 | 2838 | mremap_chunk (mchunkptr p, size_t new_size) |
f65fd747 | 2839 | { |
8a35c3fe | 2840 | size_t pagesize = GLRO (dl_pagesize); |
e9c4fe93 | 2841 | INTERNAL_SIZE_T offset = prev_size (p); |
6c8dbf00 | 2842 | INTERNAL_SIZE_T size = chunksize (p); |
f65fd747 UD |
2843 | char *cp; |
2844 | ||
6c8dbf00 OB |
2845 | assert (chunk_is_mmapped (p)); |
2846 | assert (((size + offset) & (GLRO (dl_pagesize) - 1)) == 0); | |
f65fd747 UD |
2847 | |
2848 | /* Note the extra SIZE_SZ overhead as in mmap_chunk(). */ | |
8a35c3fe | 2849 | new_size = ALIGN_UP (new_size + offset + SIZE_SZ, pagesize); |
f65fd747 | 2850 | |
68f3802d UD |
2851 | /* No need to remap if the number of pages does not change. */ |
2852 | if (size + offset == new_size) | |
2853 | return p; | |
2854 | ||
6c8dbf00 OB |
2855 | cp = (char *) __mremap ((char *) p - offset, size + offset, new_size, |
2856 | MREMAP_MAYMOVE); | |
f65fd747 | 2857 | |
6c8dbf00 OB |
2858 | if (cp == MAP_FAILED) |
2859 | return 0; | |
f65fd747 | 2860 | |
6c8dbf00 | 2861 | p = (mchunkptr) (cp + offset); |
f65fd747 | 2862 | |
6c8dbf00 | 2863 | assert (aligned_OK (chunk2mem (p))); |
f65fd747 | 2864 | |
e9c4fe93 | 2865 | assert (prev_size (p) == offset); |
6c8dbf00 | 2866 | set_head (p, (new_size - offset) | IS_MMAPPED); |
f65fd747 | 2867 | |
c6e4925d OB |
2868 | INTERNAL_SIZE_T new; |
2869 | new = atomic_exchange_and_add (&mp_.mmapped_mem, new_size - size - offset) | |
6c8dbf00 | 2870 | + new_size - size - offset; |
c6e4925d | 2871 | atomic_max (&mp_.max_mmapped_mem, new); |
f65fd747 UD |
2872 | return p; |
2873 | } | |
f65fd747 UD |
2874 | #endif /* HAVE_MREMAP */ |
2875 | ||
fa8d436c | 2876 | /*------------------------ Public wrappers. --------------------------------*/ |
f65fd747 | 2877 | |
6c8dbf00 OB |
2878 | void * |
2879 | __libc_malloc (size_t bytes) | |
fa8d436c UD |
2880 | { |
2881 | mstate ar_ptr; | |
22a89187 | 2882 | void *victim; |
f65fd747 | 2883 | |
a222d91a | 2884 | void *(*hook) (size_t, const void *) |
f3eeb3fc | 2885 | = atomic_forced_read (__malloc_hook); |
bfacf1af | 2886 | if (__builtin_expect (hook != NULL, 0)) |
fa8d436c | 2887 | return (*hook)(bytes, RETURN_ADDRESS (0)); |
f65fd747 | 2888 | |
94c5a52a | 2889 | arena_get (ar_ptr, bytes); |
425ce2ed | 2890 | |
6c8dbf00 | 2891 | victim = _int_malloc (ar_ptr, bytes); |
fff94fa2 SP |
2892 | /* Retry with another arena only if we were able to find a usable arena |
2893 | before. */ | |
2894 | if (!victim && ar_ptr != NULL) | |
6c8dbf00 OB |
2895 | { |
2896 | LIBC_PROBE (memory_malloc_retry, 1, bytes); | |
2897 | ar_ptr = arena_get_retry (ar_ptr, bytes); | |
fff94fa2 | 2898 | victim = _int_malloc (ar_ptr, bytes); |
60f0e64b | 2899 | } |
fff94fa2 SP |
2900 | |
2901 | if (ar_ptr != NULL) | |
4bf5f222 | 2902 | __libc_lock_unlock (ar_ptr->mutex); |
fff94fa2 | 2903 | |
6c8dbf00 OB |
2904 | assert (!victim || chunk_is_mmapped (mem2chunk (victim)) || |
2905 | ar_ptr == arena_for_chunk (mem2chunk (victim))); | |
fa8d436c | 2906 | return victim; |
f65fd747 | 2907 | } |
6c8dbf00 | 2908 | libc_hidden_def (__libc_malloc) |
f65fd747 | 2909 | |
fa8d436c | 2910 | void |
6c8dbf00 | 2911 | __libc_free (void *mem) |
f65fd747 | 2912 | { |
fa8d436c UD |
2913 | mstate ar_ptr; |
2914 | mchunkptr p; /* chunk corresponding to mem */ | |
2915 | ||
a222d91a | 2916 | void (*hook) (void *, const void *) |
f3eeb3fc | 2917 | = atomic_forced_read (__free_hook); |
6c8dbf00 OB |
2918 | if (__builtin_expect (hook != NULL, 0)) |
2919 | { | |
2920 | (*hook)(mem, RETURN_ADDRESS (0)); | |
2921 | return; | |
2922 | } | |
f65fd747 | 2923 | |
fa8d436c UD |
2924 | if (mem == 0) /* free(0) has no effect */ |
2925 | return; | |
f65fd747 | 2926 | |
6c8dbf00 | 2927 | p = mem2chunk (mem); |
f65fd747 | 2928 | |
6c8dbf00 OB |
2929 | if (chunk_is_mmapped (p)) /* release mmapped memory. */ |
2930 | { | |
4cf6c72f FW |
2931 | /* See if the dynamic brk/mmap threshold needs adjusting. |
2932 | Dumped fake mmapped chunks do not affect the threshold. */ | |
6c8dbf00 | 2933 | if (!mp_.no_dyn_threshold |
e9c4fe93 FW |
2934 | && chunksize_nomask (p) > mp_.mmap_threshold |
2935 | && chunksize_nomask (p) <= DEFAULT_MMAP_THRESHOLD_MAX | |
4cf6c72f | 2936 | && !DUMPED_MAIN_ARENA_CHUNK (p)) |
6c8dbf00 OB |
2937 | { |
2938 | mp_.mmap_threshold = chunksize (p); | |
2939 | mp_.trim_threshold = 2 * mp_.mmap_threshold; | |
2940 | LIBC_PROBE (memory_mallopt_free_dyn_thresholds, 2, | |
2941 | mp_.mmap_threshold, mp_.trim_threshold); | |
2942 | } | |
2943 | munmap_chunk (p); | |
2944 | return; | |
2945 | } | |
f65fd747 | 2946 | |
6c8dbf00 OB |
2947 | ar_ptr = arena_for_chunk (p); |
2948 | _int_free (ar_ptr, p, 0); | |
f65fd747 | 2949 | } |
3b49edc0 | 2950 | libc_hidden_def (__libc_free) |
f65fd747 | 2951 | |
6c8dbf00 OB |
2952 | void * |
2953 | __libc_realloc (void *oldmem, size_t bytes) | |
f65fd747 | 2954 | { |
fa8d436c | 2955 | mstate ar_ptr; |
6c8dbf00 | 2956 | INTERNAL_SIZE_T nb; /* padded request size */ |
f65fd747 | 2957 | |
6c8dbf00 | 2958 | void *newp; /* chunk to return */ |
f65fd747 | 2959 | |
a222d91a | 2960 | void *(*hook) (void *, size_t, const void *) = |
f3eeb3fc | 2961 | atomic_forced_read (__realloc_hook); |
bfacf1af | 2962 | if (__builtin_expect (hook != NULL, 0)) |
fa8d436c | 2963 | return (*hook)(oldmem, bytes, RETURN_ADDRESS (0)); |
f65fd747 | 2964 | |
fa8d436c | 2965 | #if REALLOC_ZERO_BYTES_FREES |
6c8dbf00 OB |
2966 | if (bytes == 0 && oldmem != NULL) |
2967 | { | |
2968 | __libc_free (oldmem); return 0; | |
2969 | } | |
f65fd747 | 2970 | #endif |
f65fd747 | 2971 | |
fa8d436c | 2972 | /* realloc of null is supposed to be same as malloc */ |
6c8dbf00 OB |
2973 | if (oldmem == 0) |
2974 | return __libc_malloc (bytes); | |
f65fd747 | 2975 | |
78ac92ad | 2976 | /* chunk corresponding to oldmem */ |
6c8dbf00 | 2977 | const mchunkptr oldp = mem2chunk (oldmem); |
78ac92ad | 2978 | /* its size */ |
6c8dbf00 | 2979 | const INTERNAL_SIZE_T oldsize = chunksize (oldp); |
f65fd747 | 2980 | |
fff94fa2 SP |
2981 | if (chunk_is_mmapped (oldp)) |
2982 | ar_ptr = NULL; | |
2983 | else | |
2984 | ar_ptr = arena_for_chunk (oldp); | |
2985 | ||
4cf6c72f FW |
2986 | /* Little security check which won't hurt performance: the allocator |
2987 | never wrapps around at the end of the address space. Therefore | |
2988 | we can exclude some size values which might appear here by | |
2989 | accident or by "design" from some intruder. We need to bypass | |
2990 | this check for dumped fake mmap chunks from the old main arena | |
2991 | because the new malloc may provide additional alignment. */ | |
2992 | if ((__builtin_expect ((uintptr_t) oldp > (uintptr_t) -oldsize, 0) | |
2993 | || __builtin_expect (misaligned_chunk (oldp), 0)) | |
2994 | && !DUMPED_MAIN_ARENA_CHUNK (oldp)) | |
dc165f7b | 2995 | { |
fff94fa2 SP |
2996 | malloc_printerr (check_action, "realloc(): invalid pointer", oldmem, |
2997 | ar_ptr); | |
dc165f7b UD |
2998 | return NULL; |
2999 | } | |
3000 | ||
6c8dbf00 | 3001 | checked_request2size (bytes, nb); |
f65fd747 | 3002 | |
6c8dbf00 OB |
3003 | if (chunk_is_mmapped (oldp)) |
3004 | { | |
4cf6c72f FW |
3005 | /* If this is a faked mmapped chunk from the dumped main arena, |
3006 | always make a copy (and do not free the old chunk). */ | |
3007 | if (DUMPED_MAIN_ARENA_CHUNK (oldp)) | |
3008 | { | |
3009 | /* Must alloc, copy, free. */ | |
3010 | void *newmem = __libc_malloc (bytes); | |
3011 | if (newmem == 0) | |
3012 | return NULL; | |
3013 | /* Copy as many bytes as are available from the old chunk | |
1e8a8875 FW |
3014 | and fit into the new size. NB: The overhead for faked |
3015 | mmapped chunks is only SIZE_SZ, not 2 * SIZE_SZ as for | |
3016 | regular mmapped chunks. */ | |
3017 | if (bytes > oldsize - SIZE_SZ) | |
3018 | bytes = oldsize - SIZE_SZ; | |
4cf6c72f FW |
3019 | memcpy (newmem, oldmem, bytes); |
3020 | return newmem; | |
3021 | } | |
3022 | ||
6c8dbf00 | 3023 | void *newmem; |
f65fd747 | 3024 | |
fa8d436c | 3025 | #if HAVE_MREMAP |
6c8dbf00 OB |
3026 | newp = mremap_chunk (oldp, nb); |
3027 | if (newp) | |
3028 | return chunk2mem (newp); | |
f65fd747 | 3029 | #endif |
6c8dbf00 OB |
3030 | /* Note the extra SIZE_SZ overhead. */ |
3031 | if (oldsize - SIZE_SZ >= nb) | |
3032 | return oldmem; /* do nothing */ | |
3033 | ||
3034 | /* Must alloc, copy, free. */ | |
3035 | newmem = __libc_malloc (bytes); | |
3036 | if (newmem == 0) | |
3037 | return 0; /* propagate failure */ | |
fa8d436c | 3038 | |
6c8dbf00 OB |
3039 | memcpy (newmem, oldmem, oldsize - 2 * SIZE_SZ); |
3040 | munmap_chunk (oldp); | |
3041 | return newmem; | |
3042 | } | |
3043 | ||
4bf5f222 | 3044 | __libc_lock_lock (ar_ptr->mutex); |
f65fd747 | 3045 | |
6c8dbf00 | 3046 | newp = _int_realloc (ar_ptr, oldp, oldsize, nb); |
f65fd747 | 3047 | |
4bf5f222 | 3048 | __libc_lock_unlock (ar_ptr->mutex); |
6c8dbf00 OB |
3049 | assert (!newp || chunk_is_mmapped (mem2chunk (newp)) || |
3050 | ar_ptr == arena_for_chunk (mem2chunk (newp))); | |
07014fca UD |
3051 | |
3052 | if (newp == NULL) | |
3053 | { | |
3054 | /* Try harder to allocate memory in other arenas. */ | |
35fed6f1 | 3055 | LIBC_PROBE (memory_realloc_retry, 2, bytes, oldmem); |
6c8dbf00 | 3056 | newp = __libc_malloc (bytes); |
07014fca | 3057 | if (newp != NULL) |
6c8dbf00 OB |
3058 | { |
3059 | memcpy (newp, oldmem, oldsize - SIZE_SZ); | |
3060 | _int_free (ar_ptr, oldp, 0); | |
3061 | } | |
07014fca UD |
3062 | } |
3063 | ||
fa8d436c UD |
3064 | return newp; |
3065 | } | |
3b49edc0 | 3066 | libc_hidden_def (__libc_realloc) |
f65fd747 | 3067 | |
6c8dbf00 OB |
3068 | void * |
3069 | __libc_memalign (size_t alignment, size_t bytes) | |
10ad46bc OB |
3070 | { |
3071 | void *address = RETURN_ADDRESS (0); | |
3072 | return _mid_memalign (alignment, bytes, address); | |
3073 | } | |
3074 | ||
3075 | static void * | |
3076 | _mid_memalign (size_t alignment, size_t bytes, void *address) | |
fa8d436c UD |
3077 | { |
3078 | mstate ar_ptr; | |
22a89187 | 3079 | void *p; |
f65fd747 | 3080 | |
a222d91a | 3081 | void *(*hook) (size_t, size_t, const void *) = |
f3eeb3fc | 3082 | atomic_forced_read (__memalign_hook); |
bfacf1af | 3083 | if (__builtin_expect (hook != NULL, 0)) |
10ad46bc | 3084 | return (*hook)(alignment, bytes, address); |
f65fd747 | 3085 | |
10ad46bc | 3086 | /* If we need less alignment than we give anyway, just relay to malloc. */ |
6c8dbf00 OB |
3087 | if (alignment <= MALLOC_ALIGNMENT) |
3088 | return __libc_malloc (bytes); | |
1228ed5c | 3089 | |
fa8d436c | 3090 | /* Otherwise, ensure that it is at least a minimum chunk size */ |
6c8dbf00 OB |
3091 | if (alignment < MINSIZE) |
3092 | alignment = MINSIZE; | |
f65fd747 | 3093 | |
a56ee40b WN |
3094 | /* If the alignment is greater than SIZE_MAX / 2 + 1 it cannot be a |
3095 | power of 2 and will cause overflow in the check below. */ | |
3096 | if (alignment > SIZE_MAX / 2 + 1) | |
3097 | { | |
3098 | __set_errno (EINVAL); | |
3099 | return 0; | |
3100 | } | |
3101 | ||
b73ed247 WN |
3102 | /* Check for overflow. */ |
3103 | if (bytes > SIZE_MAX - alignment - MINSIZE) | |
3104 | { | |
3105 | __set_errno (ENOMEM); | |
3106 | return 0; | |
3107 | } | |
3108 | ||
10ad46bc OB |
3109 | |
3110 | /* Make sure alignment is power of 2. */ | |
6c8dbf00 OB |
3111 | if (!powerof2 (alignment)) |
3112 | { | |
3113 | size_t a = MALLOC_ALIGNMENT * 2; | |
3114 | while (a < alignment) | |
3115 | a <<= 1; | |
3116 | alignment = a; | |
3117 | } | |
10ad46bc | 3118 | |
6c8dbf00 | 3119 | arena_get (ar_ptr, bytes + alignment + MINSIZE); |
6c8dbf00 OB |
3120 | |
3121 | p = _int_memalign (ar_ptr, alignment, bytes); | |
fff94fa2 | 3122 | if (!p && ar_ptr != NULL) |
6c8dbf00 OB |
3123 | { |
3124 | LIBC_PROBE (memory_memalign_retry, 2, bytes, alignment); | |
3125 | ar_ptr = arena_get_retry (ar_ptr, bytes); | |
fff94fa2 | 3126 | p = _int_memalign (ar_ptr, alignment, bytes); |
f65fd747 | 3127 | } |
fff94fa2 SP |
3128 | |
3129 | if (ar_ptr != NULL) | |
4bf5f222 | 3130 | __libc_lock_unlock (ar_ptr->mutex); |
fff94fa2 | 3131 | |
6c8dbf00 OB |
3132 | assert (!p || chunk_is_mmapped (mem2chunk (p)) || |
3133 | ar_ptr == arena_for_chunk (mem2chunk (p))); | |
fa8d436c | 3134 | return p; |
f65fd747 | 3135 | } |
380d7e87 | 3136 | /* For ISO C11. */ |
3b49edc0 UD |
3137 | weak_alias (__libc_memalign, aligned_alloc) |
3138 | libc_hidden_def (__libc_memalign) | |
f65fd747 | 3139 | |
6c8dbf00 OB |
3140 | void * |
3141 | __libc_valloc (size_t bytes) | |
fa8d436c | 3142 | { |
6c8dbf00 | 3143 | if (__malloc_initialized < 0) |
fa8d436c | 3144 | ptmalloc_init (); |
8088488d | 3145 | |
10ad46bc | 3146 | void *address = RETURN_ADDRESS (0); |
8a35c3fe CD |
3147 | size_t pagesize = GLRO (dl_pagesize); |
3148 | return _mid_memalign (pagesize, bytes, address); | |
fa8d436c | 3149 | } |
f65fd747 | 3150 | |
6c8dbf00 OB |
3151 | void * |
3152 | __libc_pvalloc (size_t bytes) | |
fa8d436c | 3153 | { |
6c8dbf00 | 3154 | if (__malloc_initialized < 0) |
fa8d436c | 3155 | ptmalloc_init (); |
8088488d | 3156 | |
10ad46bc | 3157 | void *address = RETURN_ADDRESS (0); |
8a35c3fe CD |
3158 | size_t pagesize = GLRO (dl_pagesize); |
3159 | size_t rounded_bytes = ALIGN_UP (bytes, pagesize); | |
dba38551 | 3160 | |
1159a193 | 3161 | /* Check for overflow. */ |
8a35c3fe | 3162 | if (bytes > SIZE_MAX - 2 * pagesize - MINSIZE) |
1159a193 WN |
3163 | { |
3164 | __set_errno (ENOMEM); | |
3165 | return 0; | |
3166 | } | |
3167 | ||
8a35c3fe | 3168 | return _mid_memalign (pagesize, rounded_bytes, address); |
fa8d436c | 3169 | } |
f65fd747 | 3170 | |
6c8dbf00 OB |
3171 | void * |
3172 | __libc_calloc (size_t n, size_t elem_size) | |
f65fd747 | 3173 | { |
d6285c9f CD |
3174 | mstate av; |
3175 | mchunkptr oldtop, p; | |
3176 | INTERNAL_SIZE_T bytes, sz, csz, oldtopsize; | |
6c8dbf00 | 3177 | void *mem; |
d6285c9f CD |
3178 | unsigned long clearsize; |
3179 | unsigned long nclears; | |
3180 | INTERNAL_SIZE_T *d; | |
0950889b UD |
3181 | |
3182 | /* size_t is unsigned so the behavior on overflow is defined. */ | |
3183 | bytes = n * elem_size; | |
d9af917d UD |
3184 | #define HALF_INTERNAL_SIZE_T \ |
3185 | (((INTERNAL_SIZE_T) 1) << (8 * sizeof (INTERNAL_SIZE_T) / 2)) | |
6c8dbf00 OB |
3186 | if (__builtin_expect ((n | elem_size) >= HALF_INTERNAL_SIZE_T, 0)) |
3187 | { | |
3188 | if (elem_size != 0 && bytes / elem_size != n) | |
3189 | { | |
3190 | __set_errno (ENOMEM); | |
3191 | return 0; | |
3192 | } | |
d9af917d | 3193 | } |
0950889b | 3194 | |
a222d91a | 3195 | void *(*hook) (size_t, const void *) = |
f3eeb3fc | 3196 | atomic_forced_read (__malloc_hook); |
6c8dbf00 OB |
3197 | if (__builtin_expect (hook != NULL, 0)) |
3198 | { | |
d6285c9f CD |
3199 | sz = bytes; |
3200 | mem = (*hook)(sz, RETURN_ADDRESS (0)); | |
3201 | if (mem == 0) | |
3202 | return 0; | |
3203 | ||
3204 | return memset (mem, 0, sz); | |
7799b7b3 | 3205 | } |
f65fd747 | 3206 | |
d6285c9f CD |
3207 | sz = bytes; |
3208 | ||
3209 | arena_get (av, sz); | |
fff94fa2 SP |
3210 | if (av) |
3211 | { | |
3212 | /* Check if we hand out the top chunk, in which case there may be no | |
3213 | need to clear. */ | |
d6285c9f | 3214 | #if MORECORE_CLEARS |
fff94fa2 SP |
3215 | oldtop = top (av); |
3216 | oldtopsize = chunksize (top (av)); | |
d6285c9f | 3217 | # if MORECORE_CLEARS < 2 |
fff94fa2 SP |
3218 | /* Only newly allocated memory is guaranteed to be cleared. */ |
3219 | if (av == &main_arena && | |
3220 | oldtopsize < mp_.sbrk_base + av->max_system_mem - (char *) oldtop) | |
3221 | oldtopsize = (mp_.sbrk_base + av->max_system_mem - (char *) oldtop); | |
d6285c9f | 3222 | # endif |
fff94fa2 SP |
3223 | if (av != &main_arena) |
3224 | { | |
3225 | heap_info *heap = heap_for_ptr (oldtop); | |
3226 | if (oldtopsize < (char *) heap + heap->mprotect_size - (char *) oldtop) | |
3227 | oldtopsize = (char *) heap + heap->mprotect_size - (char *) oldtop; | |
3228 | } | |
3229 | #endif | |
3230 | } | |
3231 | else | |
d6285c9f | 3232 | { |
fff94fa2 SP |
3233 | /* No usable arenas. */ |
3234 | oldtop = 0; | |
3235 | oldtopsize = 0; | |
d6285c9f | 3236 | } |
d6285c9f CD |
3237 | mem = _int_malloc (av, sz); |
3238 | ||
3239 | ||
3240 | assert (!mem || chunk_is_mmapped (mem2chunk (mem)) || | |
3241 | av == arena_for_chunk (mem2chunk (mem))); | |
3242 | ||
fff94fa2 | 3243 | if (mem == 0 && av != NULL) |
d6285c9f CD |
3244 | { |
3245 | LIBC_PROBE (memory_calloc_retry, 1, sz); | |
3246 | av = arena_get_retry (av, sz); | |
fff94fa2 | 3247 | mem = _int_malloc (av, sz); |
d6285c9f | 3248 | } |
fff94fa2 SP |
3249 | |
3250 | if (av != NULL) | |
4bf5f222 | 3251 | __libc_lock_unlock (av->mutex); |
fff94fa2 SP |
3252 | |
3253 | /* Allocation failed even after a retry. */ | |
3254 | if (mem == 0) | |
3255 | return 0; | |
3256 | ||
d6285c9f CD |
3257 | p = mem2chunk (mem); |
3258 | ||
3259 | /* Two optional cases in which clearing not necessary */ | |
3260 | if (chunk_is_mmapped (p)) | |
3261 | { | |
3262 | if (__builtin_expect (perturb_byte, 0)) | |
3263 | return memset (mem, 0, sz); | |
3264 | ||
3265 | return mem; | |
3266 | } | |
3267 | ||
3268 | csz = chunksize (p); | |
3269 | ||
3270 | #if MORECORE_CLEARS | |
3271 | if (perturb_byte == 0 && (p == oldtop && csz > oldtopsize)) | |
3272 | { | |
3273 | /* clear only the bytes from non-freshly-sbrked memory */ | |
3274 | csz = oldtopsize; | |
3275 | } | |
3276 | #endif | |
3277 | ||
3278 | /* Unroll clear of <= 36 bytes (72 if 8byte sizes). We know that | |
3279 | contents have an odd number of INTERNAL_SIZE_T-sized words; | |
3280 | minimally 3. */ | |
3281 | d = (INTERNAL_SIZE_T *) mem; | |
3282 | clearsize = csz - SIZE_SZ; | |
3283 | nclears = clearsize / sizeof (INTERNAL_SIZE_T); | |
3284 | assert (nclears >= 3); | |
3285 | ||
3286 | if (nclears > 9) | |
3287 | return memset (d, 0, clearsize); | |
3288 | ||
3289 | else | |
3290 | { | |
3291 | *(d + 0) = 0; | |
3292 | *(d + 1) = 0; | |
3293 | *(d + 2) = 0; | |
3294 | if (nclears > 4) | |
3295 | { | |
3296 | *(d + 3) = 0; | |
3297 | *(d + 4) = 0; | |
3298 | if (nclears > 6) | |
3299 | { | |
3300 | *(d + 5) = 0; | |
3301 | *(d + 6) = 0; | |
3302 | if (nclears > 8) | |
3303 | { | |
3304 | *(d + 7) = 0; | |
3305 | *(d + 8) = 0; | |
3306 | } | |
3307 | } | |
3308 | } | |
3309 | } | |
3310 | ||
3311 | return mem; | |
fa8d436c | 3312 | } |
f65fd747 | 3313 | |
f65fd747 | 3314 | /* |
6c8dbf00 OB |
3315 | ------------------------------ malloc ------------------------------ |
3316 | */ | |
f65fd747 | 3317 | |
6c8dbf00 OB |
3318 | static void * |
3319 | _int_malloc (mstate av, size_t bytes) | |
f65fd747 | 3320 | { |
fa8d436c | 3321 | INTERNAL_SIZE_T nb; /* normalized request size */ |
6c8dbf00 OB |
3322 | unsigned int idx; /* associated bin index */ |
3323 | mbinptr bin; /* associated bin */ | |
f65fd747 | 3324 | |
6c8dbf00 | 3325 | mchunkptr victim; /* inspected/selected chunk */ |
fa8d436c | 3326 | INTERNAL_SIZE_T size; /* its size */ |
6c8dbf00 | 3327 | int victim_index; /* its bin index */ |
f65fd747 | 3328 | |
6c8dbf00 OB |
3329 | mchunkptr remainder; /* remainder from a split */ |
3330 | unsigned long remainder_size; /* its size */ | |
8a4b65b4 | 3331 | |
6c8dbf00 OB |
3332 | unsigned int block; /* bit map traverser */ |
3333 | unsigned int bit; /* bit map traverser */ | |
3334 | unsigned int map; /* current word of binmap */ | |
8a4b65b4 | 3335 | |
6c8dbf00 OB |
3336 | mchunkptr fwd; /* misc temp for linking */ |
3337 | mchunkptr bck; /* misc temp for linking */ | |
8a4b65b4 | 3338 | |
f6887a0d UD |
3339 | const char *errstr = NULL; |
3340 | ||
fa8d436c | 3341 | /* |
6c8dbf00 OB |
3342 | Convert request size to internal form by adding SIZE_SZ bytes |
3343 | overhead plus possibly more to obtain necessary alignment and/or | |
3344 | to obtain a size of at least MINSIZE, the smallest allocatable | |
3345 | size. Also, checked_request2size traps (returning 0) request sizes | |
3346 | that are so large that they wrap around zero when padded and | |
3347 | aligned. | |
3348 | */ | |
f65fd747 | 3349 | |
6c8dbf00 | 3350 | checked_request2size (bytes, nb); |
f65fd747 | 3351 | |
fff94fa2 SP |
3352 | /* There are no usable arenas. Fall back to sysmalloc to get a chunk from |
3353 | mmap. */ | |
3354 | if (__glibc_unlikely (av == NULL)) | |
3355 | { | |
3356 | void *p = sysmalloc (nb, av); | |
3357 | if (p != NULL) | |
3358 | alloc_perturb (p, bytes); | |
3359 | return p; | |
3360 | } | |
3361 | ||
fa8d436c | 3362 | /* |
6c8dbf00 OB |
3363 | If the size qualifies as a fastbin, first check corresponding bin. |
3364 | This code is safe to execute even if av is not yet initialized, so we | |
3365 | can try it without checking, which saves some time on this fast path. | |
3366 | */ | |
f65fd747 | 3367 | |
6c8dbf00 OB |
3368 | if ((unsigned long) (nb) <= (unsigned long) (get_max_fast ())) |
3369 | { | |
3370 | idx = fastbin_index (nb); | |
3371 | mfastbinptr *fb = &fastbin (av, idx); | |
3372 | mchunkptr pp = *fb; | |
3373 | do | |
3374 | { | |
3375 | victim = pp; | |
3376 | if (victim == NULL) | |
3377 | break; | |
3378 | } | |
3379 | while ((pp = catomic_compare_and_exchange_val_acq (fb, victim->fd, victim)) | |
3380 | != victim); | |
3381 | if (victim != 0) | |
3382 | { | |
3383 | if (__builtin_expect (fastbin_index (chunksize (victim)) != idx, 0)) | |
3384 | { | |
3385 | errstr = "malloc(): memory corruption (fast)"; | |
3386 | errout: | |
fff94fa2 | 3387 | malloc_printerr (check_action, errstr, chunk2mem (victim), av); |
6c8dbf00 OB |
3388 | return NULL; |
3389 | } | |
3390 | check_remalloced_chunk (av, victim, nb); | |
3391 | void *p = chunk2mem (victim); | |
3392 | alloc_perturb (p, bytes); | |
3393 | return p; | |
3394 | } | |
fa8d436c | 3395 | } |
f65fd747 | 3396 | |
fa8d436c | 3397 | /* |
6c8dbf00 OB |
3398 | If a small request, check regular bin. Since these "smallbins" |
3399 | hold one size each, no searching within bins is necessary. | |
3400 | (For a large request, we need to wait until unsorted chunks are | |
3401 | processed to find best fit. But for small ones, fits are exact | |
3402 | anyway, so we can check now, which is faster.) | |
3403 | */ | |
3404 | ||
3405 | if (in_smallbin_range (nb)) | |
3406 | { | |
3407 | idx = smallbin_index (nb); | |
3408 | bin = bin_at (av, idx); | |
3409 | ||
3410 | if ((victim = last (bin)) != bin) | |
3411 | { | |
3412 | if (victim == 0) /* initialization check */ | |
3413 | malloc_consolidate (av); | |
3414 | else | |
3415 | { | |
3416 | bck = victim->bk; | |
a1ffb40e | 3417 | if (__glibc_unlikely (bck->fd != victim)) |
6c8dbf00 OB |
3418 | { |
3419 | errstr = "malloc(): smallbin double linked list corrupted"; | |
3420 | goto errout; | |
3421 | } | |
3422 | set_inuse_bit_at_offset (victim, nb); | |
3423 | bin->bk = bck; | |
3424 | bck->fd = bin; | |
3425 | ||
3426 | if (av != &main_arena) | |
e9c4fe93 | 3427 | set_non_main_arena (victim); |
6c8dbf00 OB |
3428 | check_malloced_chunk (av, victim, nb); |
3429 | void *p = chunk2mem (victim); | |
3430 | alloc_perturb (p, bytes); | |
3431 | return p; | |
3432 | } | |
3433 | } | |
fa8d436c | 3434 | } |
f65fd747 | 3435 | |
a9177ff5 | 3436 | /* |
fa8d436c UD |
3437 | If this is a large request, consolidate fastbins before continuing. |
3438 | While it might look excessive to kill all fastbins before | |
3439 | even seeing if there is space available, this avoids | |
3440 | fragmentation problems normally associated with fastbins. | |
3441 | Also, in practice, programs tend to have runs of either small or | |
a9177ff5 | 3442 | large requests, but less often mixtures, so consolidation is not |
fa8d436c UD |
3443 | invoked all that often in most programs. And the programs that |
3444 | it is called frequently in otherwise tend to fragment. | |
6c8dbf00 | 3445 | */ |
7799b7b3 | 3446 | |
6c8dbf00 OB |
3447 | else |
3448 | { | |
3449 | idx = largebin_index (nb); | |
3450 | if (have_fastchunks (av)) | |
3451 | malloc_consolidate (av); | |
3452 | } | |
f65fd747 | 3453 | |
fa8d436c | 3454 | /* |
6c8dbf00 OB |
3455 | Process recently freed or remaindered chunks, taking one only if |
3456 | it is exact fit, or, if this a small request, the chunk is remainder from | |
3457 | the most recent non-exact fit. Place other traversed chunks in | |
3458 | bins. Note that this step is the only place in any routine where | |
3459 | chunks are placed in bins. | |
3460 | ||
3461 | The outer loop here is needed because we might not realize until | |
3462 | near the end of malloc that we should have consolidated, so must | |
3463 | do so and retry. This happens at most once, and only when we would | |
3464 | otherwise need to expand memory to service a "small" request. | |
3465 | */ | |
3466 | ||
3467 | for (;; ) | |
3468 | { | |
3469 | int iters = 0; | |
3470 | while ((victim = unsorted_chunks (av)->bk) != unsorted_chunks (av)) | |
3471 | { | |
3472 | bck = victim->bk; | |
e9c4fe93 FW |
3473 | if (__builtin_expect (chunksize_nomask (victim) <= 2 * SIZE_SZ, 0) |
3474 | || __builtin_expect (chunksize_nomask (victim) | |
3475 | > av->system_mem, 0)) | |
6c8dbf00 | 3476 | malloc_printerr (check_action, "malloc(): memory corruption", |
fff94fa2 | 3477 | chunk2mem (victim), av); |
6c8dbf00 OB |
3478 | size = chunksize (victim); |
3479 | ||
3480 | /* | |
3481 | If a small request, try to use last remainder if it is the | |
3482 | only chunk in unsorted bin. This helps promote locality for | |
3483 | runs of consecutive small requests. This is the only | |
3484 | exception to best-fit, and applies only when there is | |
3485 | no exact fit for a small chunk. | |
3486 | */ | |
3487 | ||
3488 | if (in_smallbin_range (nb) && | |
3489 | bck == unsorted_chunks (av) && | |
3490 | victim == av->last_remainder && | |
3491 | (unsigned long) (size) > (unsigned long) (nb + MINSIZE)) | |
3492 | { | |
3493 | /* split and reattach remainder */ | |
3494 | remainder_size = size - nb; | |
3495 | remainder = chunk_at_offset (victim, nb); | |
3496 | unsorted_chunks (av)->bk = unsorted_chunks (av)->fd = remainder; | |
3497 | av->last_remainder = remainder; | |
3498 | remainder->bk = remainder->fd = unsorted_chunks (av); | |
3499 | if (!in_smallbin_range (remainder_size)) | |
3500 | { | |
3501 | remainder->fd_nextsize = NULL; | |
3502 | remainder->bk_nextsize = NULL; | |
3503 | } | |
3504 | ||
3505 | set_head (victim, nb | PREV_INUSE | | |
3506 | (av != &main_arena ? NON_MAIN_ARENA : 0)); | |
3507 | set_head (remainder, remainder_size | PREV_INUSE); | |
3508 | set_foot (remainder, remainder_size); | |
3509 | ||
3510 | check_malloced_chunk (av, victim, nb); | |
3511 | void *p = chunk2mem (victim); | |
3512 | alloc_perturb (p, bytes); | |
3513 | return p; | |
3514 | } | |
3515 | ||
3516 | /* remove from unsorted list */ | |
3517 | unsorted_chunks (av)->bk = bck; | |
3518 | bck->fd = unsorted_chunks (av); | |
3519 | ||
3520 | /* Take now instead of binning if exact fit */ | |
3521 | ||
3522 | if (size == nb) | |
3523 | { | |
3524 | set_inuse_bit_at_offset (victim, size); | |
3525 | if (av != &main_arena) | |
e9c4fe93 | 3526 | set_non_main_arena (victim); |
6c8dbf00 OB |
3527 | check_malloced_chunk (av, victim, nb); |
3528 | void *p = chunk2mem (victim); | |
3529 | alloc_perturb (p, bytes); | |
3530 | return p; | |
3531 | } | |
3532 | ||
3533 | /* place chunk in bin */ | |
3534 | ||
3535 | if (in_smallbin_range (size)) | |
3536 | { | |
3537 | victim_index = smallbin_index (size); | |
3538 | bck = bin_at (av, victim_index); | |
3539 | fwd = bck->fd; | |
3540 | } | |
3541 | else | |
3542 | { | |
3543 | victim_index = largebin_index (size); | |
3544 | bck = bin_at (av, victim_index); | |
3545 | fwd = bck->fd; | |
3546 | ||
3547 | /* maintain large bins in sorted order */ | |
3548 | if (fwd != bck) | |
3549 | { | |
3550 | /* Or with inuse bit to speed comparisons */ | |
3551 | size |= PREV_INUSE; | |
3552 | /* if smaller than smallest, bypass loop below */ | |
e9c4fe93 FW |
3553 | assert (chunk_main_arena (bck->bk)); |
3554 | if ((unsigned long) (size) | |
3555 | < (unsigned long) chunksize_nomask (bck->bk)) | |
6c8dbf00 OB |
3556 | { |
3557 | fwd = bck; | |
3558 | bck = bck->bk; | |
3559 | ||
3560 | victim->fd_nextsize = fwd->fd; | |
3561 | victim->bk_nextsize = fwd->fd->bk_nextsize; | |
3562 | fwd->fd->bk_nextsize = victim->bk_nextsize->fd_nextsize = victim; | |
3563 | } | |
3564 | else | |
3565 | { | |
e9c4fe93 FW |
3566 | assert (chunk_main_arena (fwd)); |
3567 | while ((unsigned long) size < chunksize_nomask (fwd)) | |
6c8dbf00 OB |
3568 | { |
3569 | fwd = fwd->fd_nextsize; | |
e9c4fe93 | 3570 | assert (chunk_main_arena (fwd)); |
6c8dbf00 OB |
3571 | } |
3572 | ||
e9c4fe93 FW |
3573 | if ((unsigned long) size |
3574 | == (unsigned long) chunksize_nomask (fwd)) | |
6c8dbf00 OB |
3575 | /* Always insert in the second position. */ |
3576 | fwd = fwd->fd; | |
3577 | else | |
3578 | { | |
3579 | victim->fd_nextsize = fwd; | |
3580 | victim->bk_nextsize = fwd->bk_nextsize; | |
3581 | fwd->bk_nextsize = victim; | |
3582 | victim->bk_nextsize->fd_nextsize = victim; | |
3583 | } | |
3584 | bck = fwd->bk; | |
3585 | } | |
3586 | } | |
3587 | else | |
3588 | victim->fd_nextsize = victim->bk_nextsize = victim; | |
3589 | } | |
3590 | ||
3591 | mark_bin (av, victim_index); | |
3592 | victim->bk = bck; | |
3593 | victim->fd = fwd; | |
3594 | fwd->bk = victim; | |
3595 | bck->fd = victim; | |
3596 | ||
3597 | #define MAX_ITERS 10000 | |
3598 | if (++iters >= MAX_ITERS) | |
3599 | break; | |
3600 | } | |
fa8d436c | 3601 | |
a9177ff5 | 3602 | /* |
6c8dbf00 OB |
3603 | If a large request, scan through the chunks of current bin in |
3604 | sorted order to find smallest that fits. Use the skip list for this. | |
3605 | */ | |
3606 | ||
3607 | if (!in_smallbin_range (nb)) | |
3608 | { | |
3609 | bin = bin_at (av, idx); | |
3610 | ||
3611 | /* skip scan if empty or largest chunk is too small */ | |
e9c4fe93 FW |
3612 | if ((victim = first (bin)) != bin |
3613 | && (unsigned long) chunksize_nomask (victim) | |
3614 | >= (unsigned long) (nb)) | |
6c8dbf00 OB |
3615 | { |
3616 | victim = victim->bk_nextsize; | |
3617 | while (((unsigned long) (size = chunksize (victim)) < | |
3618 | (unsigned long) (nb))) | |
3619 | victim = victim->bk_nextsize; | |
3620 | ||
3621 | /* Avoid removing the first entry for a size so that the skip | |
3622 | list does not have to be rerouted. */ | |
e9c4fe93 FW |
3623 | if (victim != last (bin) |
3624 | && chunksize_nomask (victim) | |
3625 | == chunksize_nomask (victim->fd)) | |
6c8dbf00 OB |
3626 | victim = victim->fd; |
3627 | ||
3628 | remainder_size = size - nb; | |
fff94fa2 | 3629 | unlink (av, victim, bck, fwd); |
6c8dbf00 OB |
3630 | |
3631 | /* Exhaust */ | |
3632 | if (remainder_size < MINSIZE) | |
3633 | { | |
3634 | set_inuse_bit_at_offset (victim, size); | |
3635 | if (av != &main_arena) | |
e9c4fe93 | 3636 | set_non_main_arena (victim); |
6c8dbf00 OB |
3637 | } |
3638 | /* Split */ | |
3639 | else | |
3640 | { | |
3641 | remainder = chunk_at_offset (victim, nb); | |
3642 | /* We cannot assume the unsorted list is empty and therefore | |
3643 | have to perform a complete insert here. */ | |
3644 | bck = unsorted_chunks (av); | |
3645 | fwd = bck->fd; | |
a1ffb40e | 3646 | if (__glibc_unlikely (fwd->bk != bck)) |
6c8dbf00 OB |
3647 | { |
3648 | errstr = "malloc(): corrupted unsorted chunks"; | |
3649 | goto errout; | |
3650 | } | |
3651 | remainder->bk = bck; | |
3652 | remainder->fd = fwd; | |
3653 | bck->fd = remainder; | |
3654 | fwd->bk = remainder; | |
3655 | if (!in_smallbin_range (remainder_size)) | |
3656 | { | |
3657 | remainder->fd_nextsize = NULL; | |
3658 | remainder->bk_nextsize = NULL; | |
3659 | } | |
3660 | set_head (victim, nb | PREV_INUSE | | |
3661 | (av != &main_arena ? NON_MAIN_ARENA : 0)); | |
3662 | set_head (remainder, remainder_size | PREV_INUSE); | |
3663 | set_foot (remainder, remainder_size); | |
3664 | } | |
3665 | check_malloced_chunk (av, victim, nb); | |
3666 | void *p = chunk2mem (victim); | |
3667 | alloc_perturb (p, bytes); | |
3668 | return p; | |
3669 | } | |
3670 | } | |
f65fd747 | 3671 | |
6c8dbf00 OB |
3672 | /* |
3673 | Search for a chunk by scanning bins, starting with next largest | |
3674 | bin. This search is strictly by best-fit; i.e., the smallest | |
3675 | (with ties going to approximately the least recently used) chunk | |
3676 | that fits is selected. | |
3677 | ||
3678 | The bitmap avoids needing to check that most blocks are nonempty. | |
3679 | The particular case of skipping all bins during warm-up phases | |
3680 | when no chunks have been returned yet is faster than it might look. | |
3681 | */ | |
3682 | ||
3683 | ++idx; | |
3684 | bin = bin_at (av, idx); | |
3685 | block = idx2block (idx); | |
3686 | map = av->binmap[block]; | |
3687 | bit = idx2bit (idx); | |
3688 | ||
3689 | for (;; ) | |
3690 | { | |
3691 | /* Skip rest of block if there are no more set bits in this block. */ | |
3692 | if (bit > map || bit == 0) | |
3693 | { | |
3694 | do | |
3695 | { | |
3696 | if (++block >= BINMAPSIZE) /* out of bins */ | |
3697 | goto use_top; | |
3698 | } | |
3699 | while ((map = av->binmap[block]) == 0); | |
3700 | ||
3701 | bin = bin_at (av, (block << BINMAPSHIFT)); | |
3702 | bit = 1; | |
3703 | } | |
3704 | ||
3705 | /* Advance to bin with set bit. There must be one. */ | |
3706 | while ((bit & map) == 0) | |
3707 | { | |
3708 | bin = next_bin (bin); | |
3709 | bit <<= 1; | |
3710 | assert (bit != 0); | |
3711 | } | |
3712 | ||
3713 | /* Inspect the bin. It is likely to be non-empty */ | |
3714 | victim = last (bin); | |
3715 | ||
3716 | /* If a false alarm (empty bin), clear the bit. */ | |
3717 | if (victim == bin) | |
3718 | { | |
3719 | av->binmap[block] = map &= ~bit; /* Write through */ | |
3720 | bin = next_bin (bin); | |
3721 | bit <<= 1; | |
3722 | } | |
3723 | ||
3724 | else | |
3725 | { | |
3726 | size = chunksize (victim); | |
3727 | ||
3728 | /* We know the first chunk in this bin is big enough to use. */ | |
3729 | assert ((unsigned long) (size) >= (unsigned long) (nb)); | |
3730 | ||
3731 | remainder_size = size - nb; | |
3732 | ||
3733 | /* unlink */ | |
fff94fa2 | 3734 | unlink (av, victim, bck, fwd); |
6c8dbf00 OB |
3735 | |
3736 | /* Exhaust */ | |
3737 | if (remainder_size < MINSIZE) | |
3738 | { | |
3739 | set_inuse_bit_at_offset (victim, size); | |
3740 | if (av != &main_arena) | |
e9c4fe93 | 3741 | set_non_main_arena (victim); |
6c8dbf00 OB |
3742 | } |
3743 | ||
3744 | /* Split */ | |
3745 | else | |
3746 | { | |
3747 | remainder = chunk_at_offset (victim, nb); | |
3748 | ||
3749 | /* We cannot assume the unsorted list is empty and therefore | |
3750 | have to perform a complete insert here. */ | |
3751 | bck = unsorted_chunks (av); | |
3752 | fwd = bck->fd; | |
a1ffb40e | 3753 | if (__glibc_unlikely (fwd->bk != bck)) |
6c8dbf00 OB |
3754 | { |
3755 | errstr = "malloc(): corrupted unsorted chunks 2"; | |
3756 | goto errout; | |
3757 | } | |
3758 | remainder->bk = bck; | |
3759 | remainder->fd = fwd; | |
3760 | bck->fd = remainder; | |
3761 | fwd->bk = remainder; | |
3762 | ||
3763 | /* advertise as last remainder */ | |
3764 | if (in_smallbin_range (nb)) | |
3765 | av->last_remainder = remainder; | |
3766 | if (!in_smallbin_range (remainder_size)) | |
3767 | { | |
3768 | remainder->fd_nextsize = NULL; | |
3769 | remainder->bk_nextsize = NULL; | |
3770 | } | |
3771 | set_head (victim, nb | PREV_INUSE | | |
3772 | (av != &main_arena ? NON_MAIN_ARENA : 0)); | |
3773 | set_head (remainder, remainder_size | PREV_INUSE); | |
3774 | set_foot (remainder, remainder_size); | |
3775 | } | |
3776 | check_malloced_chunk (av, victim, nb); | |
3777 | void *p = chunk2mem (victim); | |
3778 | alloc_perturb (p, bytes); | |
3779 | return p; | |
3780 | } | |
3781 | } | |
3782 | ||
3783 | use_top: | |
3784 | /* | |
3785 | If large enough, split off the chunk bordering the end of memory | |
3786 | (held in av->top). Note that this is in accord with the best-fit | |
3787 | search rule. In effect, av->top is treated as larger (and thus | |
3788 | less well fitting) than any other available chunk since it can | |
3789 | be extended to be as large as necessary (up to system | |
3790 | limitations). | |
3791 | ||
3792 | We require that av->top always exists (i.e., has size >= | |
3793 | MINSIZE) after initialization, so if it would otherwise be | |
3794 | exhausted by current request, it is replenished. (The main | |
3795 | reason for ensuring it exists is that we may need MINSIZE space | |
3796 | to put in fenceposts in sysmalloc.) | |
3797 | */ | |
3798 | ||
3799 | victim = av->top; | |
3800 | size = chunksize (victim); | |
3801 | ||
3802 | if ((unsigned long) (size) >= (unsigned long) (nb + MINSIZE)) | |
3803 | { | |
3804 | remainder_size = size - nb; | |
3805 | remainder = chunk_at_offset (victim, nb); | |
3806 | av->top = remainder; | |
3807 | set_head (victim, nb | PREV_INUSE | | |
3808 | (av != &main_arena ? NON_MAIN_ARENA : 0)); | |
3809 | set_head (remainder, remainder_size | PREV_INUSE); | |
3810 | ||
3811 | check_malloced_chunk (av, victim, nb); | |
3812 | void *p = chunk2mem (victim); | |
3813 | alloc_perturb (p, bytes); | |
3814 | return p; | |
3815 | } | |
3816 | ||
3817 | /* When we are using atomic ops to free fast chunks we can get | |
3818 | here for all block sizes. */ | |
3819 | else if (have_fastchunks (av)) | |
3820 | { | |
3821 | malloc_consolidate (av); | |
3822 | /* restore original bin index */ | |
3823 | if (in_smallbin_range (nb)) | |
3824 | idx = smallbin_index (nb); | |
3825 | else | |
3826 | idx = largebin_index (nb); | |
3827 | } | |
f65fd747 | 3828 | |
6c8dbf00 OB |
3829 | /* |
3830 | Otherwise, relay to handle system-dependent cases | |
3831 | */ | |
425ce2ed | 3832 | else |
6c8dbf00 OB |
3833 | { |
3834 | void *p = sysmalloc (nb, av); | |
3835 | if (p != NULL) | |
3836 | alloc_perturb (p, bytes); | |
3837 | return p; | |
3838 | } | |
425ce2ed | 3839 | } |
fa8d436c | 3840 | } |
f65fd747 | 3841 | |
fa8d436c | 3842 | /* |
6c8dbf00 OB |
3843 | ------------------------------ free ------------------------------ |
3844 | */ | |
f65fd747 | 3845 | |
78ac92ad | 3846 | static void |
6c8dbf00 | 3847 | _int_free (mstate av, mchunkptr p, int have_lock) |
f65fd747 | 3848 | { |
fa8d436c | 3849 | INTERNAL_SIZE_T size; /* its size */ |
6c8dbf00 OB |
3850 | mfastbinptr *fb; /* associated fastbin */ |
3851 | mchunkptr nextchunk; /* next contiguous chunk */ | |
fa8d436c | 3852 | INTERNAL_SIZE_T nextsize; /* its size */ |
6c8dbf00 | 3853 | int nextinuse; /* true if nextchunk is used */ |
fa8d436c | 3854 | INTERNAL_SIZE_T prevsize; /* size of previous contiguous chunk */ |
6c8dbf00 OB |
3855 | mchunkptr bck; /* misc temp for linking */ |
3856 | mchunkptr fwd; /* misc temp for linking */ | |
fa8d436c | 3857 | |
37fa1953 | 3858 | const char *errstr = NULL; |
425ce2ed | 3859 | int locked = 0; |
f65fd747 | 3860 | |
6c8dbf00 | 3861 | size = chunksize (p); |
f65fd747 | 3862 | |
37fa1953 UD |
3863 | /* Little security check which won't hurt performance: the |
3864 | allocator never wrapps around at the end of the address space. | |
3865 | Therefore we can exclude some size values which might appear | |
3866 | here by accident or by "design" from some intruder. */ | |
dc165f7b | 3867 | if (__builtin_expect ((uintptr_t) p > (uintptr_t) -size, 0) |
073f560e | 3868 | || __builtin_expect (misaligned_chunk (p), 0)) |
37fa1953 UD |
3869 | { |
3870 | errstr = "free(): invalid pointer"; | |
3871 | errout: | |
6c8dbf00 | 3872 | if (!have_lock && locked) |
4bf5f222 | 3873 | __libc_lock_unlock (av->mutex); |
fff94fa2 | 3874 | malloc_printerr (check_action, errstr, chunk2mem (p), av); |
37fa1953 | 3875 | return; |
fa8d436c | 3876 | } |
347c92e9 L |
3877 | /* We know that each chunk is at least MINSIZE bytes in size or a |
3878 | multiple of MALLOC_ALIGNMENT. */ | |
a1ffb40e | 3879 | if (__glibc_unlikely (size < MINSIZE || !aligned_OK (size))) |
bf589066 UD |
3880 | { |
3881 | errstr = "free(): invalid size"; | |
3882 | goto errout; | |
3883 | } | |
f65fd747 | 3884 | |
37fa1953 | 3885 | check_inuse_chunk(av, p); |
f65fd747 | 3886 | |
37fa1953 UD |
3887 | /* |
3888 | If eligible, place chunk on a fastbin so it can be found | |
3889 | and used quickly in malloc. | |
3890 | */ | |
6bf4302e | 3891 | |
9bf248c6 | 3892 | if ((unsigned long)(size) <= (unsigned long)(get_max_fast ()) |
6bf4302e | 3893 | |
37fa1953 UD |
3894 | #if TRIM_FASTBINS |
3895 | /* | |
3896 | If TRIM_FASTBINS set, don't place chunks | |
3897 | bordering top into fastbins | |
3898 | */ | |
3899 | && (chunk_at_offset(p, size) != av->top) | |
3900 | #endif | |
3901 | ) { | |
fa8d436c | 3902 | |
e9c4fe93 FW |
3903 | if (__builtin_expect (chunksize_nomask (chunk_at_offset (p, size)) |
3904 | <= 2 * SIZE_SZ, 0) | |
893e6098 UD |
3905 | || __builtin_expect (chunksize (chunk_at_offset (p, size)) |
3906 | >= av->system_mem, 0)) | |
3907 | { | |
bec466d9 UD |
3908 | /* We might not have a lock at this point and concurrent modifications |
3909 | of system_mem might have let to a false positive. Redo the test | |
3910 | after getting the lock. */ | |
3911 | if (have_lock | |
3912 | || ({ assert (locked == 0); | |
4bf5f222 | 3913 | __libc_lock_lock (av->mutex); |
bec466d9 | 3914 | locked = 1; |
e9c4fe93 | 3915 | chunksize_nomask (chunk_at_offset (p, size)) <= 2 * SIZE_SZ |
bec466d9 UD |
3916 | || chunksize (chunk_at_offset (p, size)) >= av->system_mem; |
3917 | })) | |
bec466d9 UD |
3918 | { |
3919 | errstr = "free(): invalid next size (fast)"; | |
3920 | goto errout; | |
3921 | } | |
bec466d9 UD |
3922 | if (! have_lock) |
3923 | { | |
4bf5f222 | 3924 | __libc_lock_unlock (av->mutex); |
bec466d9 UD |
3925 | locked = 0; |
3926 | } | |
893e6098 UD |
3927 | } |
3928 | ||
e8349efd | 3929 | free_perturb (chunk2mem(p), size - 2 * SIZE_SZ); |
425ce2ed | 3930 | |
37fa1953 | 3931 | set_fastchunks(av); |
90a3055e UD |
3932 | unsigned int idx = fastbin_index(size); |
3933 | fb = &fastbin (av, idx); | |
425ce2ed | 3934 | |
362b47fe MK |
3935 | /* Atomically link P to its fastbin: P->FD = *FB; *FB = P; */ |
3936 | mchunkptr old = *fb, old2; | |
5f24d53a | 3937 | unsigned int old_idx = ~0u; |
425ce2ed UD |
3938 | do |
3939 | { | |
362b47fe MK |
3940 | /* Check that the top of the bin is not the record we are going to add |
3941 | (i.e., double free). */ | |
425ce2ed UD |
3942 | if (__builtin_expect (old == p, 0)) |
3943 | { | |
3944 | errstr = "double free or corruption (fasttop)"; | |
3945 | goto errout; | |
3946 | } | |
362b47fe MK |
3947 | /* Check that size of fastbin chunk at the top is the same as |
3948 | size of the chunk that we are adding. We can dereference OLD | |
3949 | only if we have the lock, otherwise it might have already been | |
3950 | deallocated. See use of OLD_IDX below for the actual check. */ | |
3951 | if (have_lock && old != NULL) | |
5f24d53a | 3952 | old_idx = fastbin_index(chunksize(old)); |
362b47fe | 3953 | p->fd = old2 = old; |
425ce2ed | 3954 | } |
362b47fe | 3955 | while ((old = catomic_compare_and_exchange_val_rel (fb, p, old2)) != old2); |
5f24d53a | 3956 | |
362b47fe | 3957 | if (have_lock && old != NULL && __builtin_expect (old_idx != idx, 0)) |
5f24d53a UD |
3958 | { |
3959 | errstr = "invalid fastbin entry (free)"; | |
3960 | goto errout; | |
3961 | } | |
37fa1953 | 3962 | } |
f65fd747 | 3963 | |
37fa1953 UD |
3964 | /* |
3965 | Consolidate other non-mmapped chunks as they arrive. | |
3966 | */ | |
fa8d436c | 3967 | |
37fa1953 | 3968 | else if (!chunk_is_mmapped(p)) { |
425ce2ed | 3969 | if (! have_lock) { |
4bf5f222 | 3970 | __libc_lock_lock (av->mutex); |
425ce2ed UD |
3971 | locked = 1; |
3972 | } | |
425ce2ed | 3973 | |
37fa1953 | 3974 | nextchunk = chunk_at_offset(p, size); |
fa8d436c | 3975 | |
37fa1953 UD |
3976 | /* Lightweight tests: check whether the block is already the |
3977 | top block. */ | |
a1ffb40e | 3978 | if (__glibc_unlikely (p == av->top)) |
37fa1953 UD |
3979 | { |
3980 | errstr = "double free or corruption (top)"; | |
3981 | goto errout; | |
3982 | } | |
3983 | /* Or whether the next chunk is beyond the boundaries of the arena. */ | |
3984 | if (__builtin_expect (contiguous (av) | |
3985 | && (char *) nextchunk | |
3986 | >= ((char *) av->top + chunksize(av->top)), 0)) | |
3987 | { | |
3988 | errstr = "double free or corruption (out)"; | |
3989 | goto errout; | |
3990 | } | |
3991 | /* Or whether the block is actually not marked used. */ | |
a1ffb40e | 3992 | if (__glibc_unlikely (!prev_inuse(nextchunk))) |
37fa1953 UD |
3993 | { |
3994 | errstr = "double free or corruption (!prev)"; | |
3995 | goto errout; | |
3996 | } | |
fa8d436c | 3997 | |
37fa1953 | 3998 | nextsize = chunksize(nextchunk); |
e9c4fe93 | 3999 | if (__builtin_expect (chunksize_nomask (nextchunk) <= 2 * SIZE_SZ, 0) |
893e6098 UD |
4000 | || __builtin_expect (nextsize >= av->system_mem, 0)) |
4001 | { | |
76761b63 | 4002 | errstr = "free(): invalid next size (normal)"; |
893e6098 UD |
4003 | goto errout; |
4004 | } | |
fa8d436c | 4005 | |
e8349efd | 4006 | free_perturb (chunk2mem(p), size - 2 * SIZE_SZ); |
854278df | 4007 | |
37fa1953 UD |
4008 | /* consolidate backward */ |
4009 | if (!prev_inuse(p)) { | |
e9c4fe93 | 4010 | prevsize = prev_size (p); |
37fa1953 UD |
4011 | size += prevsize; |
4012 | p = chunk_at_offset(p, -((long) prevsize)); | |
fff94fa2 | 4013 | unlink(av, p, bck, fwd); |
37fa1953 | 4014 | } |
a9177ff5 | 4015 | |
37fa1953 UD |
4016 | if (nextchunk != av->top) { |
4017 | /* get and clear inuse bit */ | |
4018 | nextinuse = inuse_bit_at_offset(nextchunk, nextsize); | |
4019 | ||
4020 | /* consolidate forward */ | |
4021 | if (!nextinuse) { | |
fff94fa2 | 4022 | unlink(av, nextchunk, bck, fwd); |
37fa1953 UD |
4023 | size += nextsize; |
4024 | } else | |
4025 | clear_inuse_bit_at_offset(nextchunk, 0); | |
10dc2a90 | 4026 | |
fa8d436c | 4027 | /* |
37fa1953 UD |
4028 | Place the chunk in unsorted chunk list. Chunks are |
4029 | not placed into regular bins until after they have | |
4030 | been given one chance to be used in malloc. | |
fa8d436c | 4031 | */ |
f65fd747 | 4032 | |
37fa1953 UD |
4033 | bck = unsorted_chunks(av); |
4034 | fwd = bck->fd; | |
a1ffb40e | 4035 | if (__glibc_unlikely (fwd->bk != bck)) |
f6887a0d UD |
4036 | { |
4037 | errstr = "free(): corrupted unsorted chunks"; | |
4038 | goto errout; | |
4039 | } | |
37fa1953 | 4040 | p->fd = fwd; |
7ecfbd38 UD |
4041 | p->bk = bck; |
4042 | if (!in_smallbin_range(size)) | |
4043 | { | |
4044 | p->fd_nextsize = NULL; | |
4045 | p->bk_nextsize = NULL; | |
4046 | } | |
37fa1953 UD |
4047 | bck->fd = p; |
4048 | fwd->bk = p; | |
8a4b65b4 | 4049 | |
37fa1953 UD |
4050 | set_head(p, size | PREV_INUSE); |
4051 | set_foot(p, size); | |
4052 | ||
4053 | check_free_chunk(av, p); | |
4054 | } | |
4055 | ||
4056 | /* | |
4057 | If the chunk borders the current high end of memory, | |
4058 | consolidate into top | |
4059 | */ | |
4060 | ||
4061 | else { | |
4062 | size += nextsize; | |
4063 | set_head(p, size | PREV_INUSE); | |
4064 | av->top = p; | |
4065 | check_chunk(av, p); | |
4066 | } | |
4067 | ||
4068 | /* | |
4069 | If freeing a large space, consolidate possibly-surrounding | |
4070 | chunks. Then, if the total unused topmost memory exceeds trim | |
4071 | threshold, ask malloc_trim to reduce top. | |
4072 | ||
4073 | Unless max_fast is 0, we don't know if there are fastbins | |
4074 | bordering top, so we cannot tell for sure whether threshold | |
4075 | has been reached unless fastbins are consolidated. But we | |
4076 | don't want to consolidate on each free. As a compromise, | |
4077 | consolidation is performed if FASTBIN_CONSOLIDATION_THRESHOLD | |
4078 | is reached. | |
4079 | */ | |
fa8d436c | 4080 | |
37fa1953 UD |
4081 | if ((unsigned long)(size) >= FASTBIN_CONSOLIDATION_THRESHOLD) { |
4082 | if (have_fastchunks(av)) | |
4083 | malloc_consolidate(av); | |
fa8d436c | 4084 | |
37fa1953 | 4085 | if (av == &main_arena) { |
a9177ff5 | 4086 | #ifndef MORECORE_CANNOT_TRIM |
37fa1953 UD |
4087 | if ((unsigned long)(chunksize(av->top)) >= |
4088 | (unsigned long)(mp_.trim_threshold)) | |
3b49edc0 | 4089 | systrim(mp_.top_pad, av); |
fa8d436c | 4090 | #endif |
37fa1953 UD |
4091 | } else { |
4092 | /* Always try heap_trim(), even if the top chunk is not | |
4093 | large, because the corresponding heap might go away. */ | |
4094 | heap_info *heap = heap_for_ptr(top(av)); | |
fa8d436c | 4095 | |
37fa1953 UD |
4096 | assert(heap->ar_ptr == av); |
4097 | heap_trim(heap, mp_.top_pad); | |
fa8d436c | 4098 | } |
fa8d436c | 4099 | } |
10dc2a90 | 4100 | |
425ce2ed UD |
4101 | if (! have_lock) { |
4102 | assert (locked); | |
4bf5f222 | 4103 | __libc_lock_unlock (av->mutex); |
425ce2ed | 4104 | } |
37fa1953 UD |
4105 | } |
4106 | /* | |
22a89187 | 4107 | If the chunk was allocated via mmap, release via munmap(). |
37fa1953 UD |
4108 | */ |
4109 | ||
4110 | else { | |
c120d94d | 4111 | munmap_chunk (p); |
fa8d436c | 4112 | } |
10dc2a90 UD |
4113 | } |
4114 | ||
fa8d436c UD |
4115 | /* |
4116 | ------------------------- malloc_consolidate ------------------------- | |
4117 | ||
4118 | malloc_consolidate is a specialized version of free() that tears | |
4119 | down chunks held in fastbins. Free itself cannot be used for this | |
4120 | purpose since, among other things, it might place chunks back onto | |
4121 | fastbins. So, instead, we need to use a minor variant of the same | |
4122 | code. | |
a9177ff5 | 4123 | |
fa8d436c UD |
4124 | Also, because this routine needs to be called the first time through |
4125 | malloc anyway, it turns out to be the perfect place to trigger | |
4126 | initialization code. | |
4127 | */ | |
4128 | ||
fa8d436c | 4129 | static void malloc_consolidate(mstate av) |
10dc2a90 | 4130 | { |
fa8d436c UD |
4131 | mfastbinptr* fb; /* current fastbin being consolidated */ |
4132 | mfastbinptr* maxfb; /* last fastbin (for loop control) */ | |
4133 | mchunkptr p; /* current chunk being consolidated */ | |
4134 | mchunkptr nextp; /* next chunk to consolidate */ | |
4135 | mchunkptr unsorted_bin; /* bin header */ | |
4136 | mchunkptr first_unsorted; /* chunk to link to */ | |
4137 | ||
4138 | /* These have same use as in free() */ | |
4139 | mchunkptr nextchunk; | |
4140 | INTERNAL_SIZE_T size; | |
4141 | INTERNAL_SIZE_T nextsize; | |
4142 | INTERNAL_SIZE_T prevsize; | |
4143 | int nextinuse; | |
4144 | mchunkptr bck; | |
4145 | mchunkptr fwd; | |
10dc2a90 | 4146 | |
fa8d436c UD |
4147 | /* |
4148 | If max_fast is 0, we know that av hasn't | |
4149 | yet been initialized, in which case do so below | |
4150 | */ | |
10dc2a90 | 4151 | |
9bf248c6 | 4152 | if (get_max_fast () != 0) { |
fa8d436c | 4153 | clear_fastchunks(av); |
10dc2a90 | 4154 | |
fa8d436c | 4155 | unsorted_bin = unsorted_chunks(av); |
10dc2a90 | 4156 | |
fa8d436c UD |
4157 | /* |
4158 | Remove each chunk from fast bin and consolidate it, placing it | |
4159 | then in unsorted bin. Among other reasons for doing this, | |
4160 | placing in unsorted bin avoids needing to calculate actual bins | |
4161 | until malloc is sure that chunks aren't immediately going to be | |
4162 | reused anyway. | |
4163 | */ | |
a9177ff5 | 4164 | |
425ce2ed | 4165 | maxfb = &fastbin (av, NFASTBINS - 1); |
425ce2ed | 4166 | fb = &fastbin (av, 0); |
fa8d436c | 4167 | do { |
b43f552a | 4168 | p = atomic_exchange_acq (fb, NULL); |
425ce2ed | 4169 | if (p != 0) { |
72f90263 UD |
4170 | do { |
4171 | check_inuse_chunk(av, p); | |
4172 | nextp = p->fd; | |
4173 | ||
4174 | /* Slightly streamlined version of consolidation code in free() */ | |
e9c4fe93 | 4175 | size = chunksize (p); |
72f90263 UD |
4176 | nextchunk = chunk_at_offset(p, size); |
4177 | nextsize = chunksize(nextchunk); | |
4178 | ||
4179 | if (!prev_inuse(p)) { | |
e9c4fe93 | 4180 | prevsize = prev_size (p); |
72f90263 UD |
4181 | size += prevsize; |
4182 | p = chunk_at_offset(p, -((long) prevsize)); | |
fff94fa2 | 4183 | unlink(av, p, bck, fwd); |
72f90263 UD |
4184 | } |
4185 | ||
4186 | if (nextchunk != av->top) { | |
4187 | nextinuse = inuse_bit_at_offset(nextchunk, nextsize); | |
4188 | ||
4189 | if (!nextinuse) { | |
4190 | size += nextsize; | |
fff94fa2 | 4191 | unlink(av, nextchunk, bck, fwd); |
72f90263 | 4192 | } else |
fa8d436c | 4193 | clear_inuse_bit_at_offset(nextchunk, 0); |
a9177ff5 | 4194 | |
72f90263 UD |
4195 | first_unsorted = unsorted_bin->fd; |
4196 | unsorted_bin->fd = p; | |
4197 | first_unsorted->bk = p; | |
a9177ff5 | 4198 | |
72f90263 | 4199 | if (!in_smallbin_range (size)) { |
7ecfbd38 UD |
4200 | p->fd_nextsize = NULL; |
4201 | p->bk_nextsize = NULL; | |
4202 | } | |
4203 | ||
72f90263 UD |
4204 | set_head(p, size | PREV_INUSE); |
4205 | p->bk = unsorted_bin; | |
4206 | p->fd = first_unsorted; | |
4207 | set_foot(p, size); | |
4208 | } | |
a9177ff5 | 4209 | |
72f90263 UD |
4210 | else { |
4211 | size += nextsize; | |
4212 | set_head(p, size | PREV_INUSE); | |
4213 | av->top = p; | |
4214 | } | |
a9177ff5 | 4215 | |
72f90263 | 4216 | } while ( (p = nextp) != 0); |
a9177ff5 | 4217 | |
fa8d436c UD |
4218 | } |
4219 | } while (fb++ != maxfb); | |
4220 | } | |
4221 | else { | |
4222 | malloc_init_state(av); | |
4223 | check_malloc_state(av); | |
4224 | } | |
4225 | } | |
10dc2a90 | 4226 | |
fa8d436c UD |
4227 | /* |
4228 | ------------------------------ realloc ------------------------------ | |
4229 | */ | |
f65fd747 | 4230 | |
22a89187 | 4231 | void* |
4c8b8cc3 UD |
4232 | _int_realloc(mstate av, mchunkptr oldp, INTERNAL_SIZE_T oldsize, |
4233 | INTERNAL_SIZE_T nb) | |
fa8d436c | 4234 | { |
fa8d436c UD |
4235 | mchunkptr newp; /* chunk to return */ |
4236 | INTERNAL_SIZE_T newsize; /* its size */ | |
22a89187 | 4237 | void* newmem; /* corresponding user mem */ |
f65fd747 | 4238 | |
fa8d436c | 4239 | mchunkptr next; /* next contiguous chunk after oldp */ |
f65fd747 | 4240 | |
fa8d436c UD |
4241 | mchunkptr remainder; /* extra space at end of newp */ |
4242 | unsigned long remainder_size; /* its size */ | |
f65fd747 | 4243 | |
fa8d436c UD |
4244 | mchunkptr bck; /* misc temp for linking */ |
4245 | mchunkptr fwd; /* misc temp for linking */ | |
2ed5fd9a | 4246 | |
fa8d436c UD |
4247 | unsigned long copysize; /* bytes to copy */ |
4248 | unsigned int ncopies; /* INTERNAL_SIZE_T words to copy */ | |
a9177ff5 | 4249 | INTERNAL_SIZE_T* s; /* copy source */ |
fa8d436c | 4250 | INTERNAL_SIZE_T* d; /* copy destination */ |
f65fd747 | 4251 | |
76761b63 | 4252 | const char *errstr = NULL; |
f65fd747 | 4253 | |
6dd6a580 | 4254 | /* oldmem size */ |
e9c4fe93 | 4255 | if (__builtin_expect (chunksize_nomask (oldp) <= 2 * SIZE_SZ, 0) |
76761b63 UD |
4256 | || __builtin_expect (oldsize >= av->system_mem, 0)) |
4257 | { | |
4b04154d | 4258 | errstr = "realloc(): invalid old size"; |
4c8b8cc3 | 4259 | errout: |
fff94fa2 | 4260 | malloc_printerr (check_action, errstr, chunk2mem (oldp), av); |
4c8b8cc3 | 4261 | return NULL; |
76761b63 UD |
4262 | } |
4263 | ||
6c8dbf00 | 4264 | check_inuse_chunk (av, oldp); |
f65fd747 | 4265 | |
4c8b8cc3 | 4266 | /* All callers already filter out mmap'ed chunks. */ |
6c8dbf00 | 4267 | assert (!chunk_is_mmapped (oldp)); |
f65fd747 | 4268 | |
6c8dbf00 OB |
4269 | next = chunk_at_offset (oldp, oldsize); |
4270 | INTERNAL_SIZE_T nextsize = chunksize (next); | |
e9c4fe93 | 4271 | if (__builtin_expect (chunksize_nomask (next) <= 2 * SIZE_SZ, 0) |
22a89187 UD |
4272 | || __builtin_expect (nextsize >= av->system_mem, 0)) |
4273 | { | |
4274 | errstr = "realloc(): invalid next size"; | |
4275 | goto errout; | |
4276 | } | |
4277 | ||
6c8dbf00 OB |
4278 | if ((unsigned long) (oldsize) >= (unsigned long) (nb)) |
4279 | { | |
4280 | /* already big enough; split below */ | |
fa8d436c | 4281 | newp = oldp; |
6c8dbf00 | 4282 | newsize = oldsize; |
7799b7b3 | 4283 | } |
f65fd747 | 4284 | |
6c8dbf00 OB |
4285 | else |
4286 | { | |
4287 | /* Try to expand forward into top */ | |
4288 | if (next == av->top && | |
4289 | (unsigned long) (newsize = oldsize + nextsize) >= | |
4290 | (unsigned long) (nb + MINSIZE)) | |
4291 | { | |
4292 | set_head_size (oldp, nb | (av != &main_arena ? NON_MAIN_ARENA : 0)); | |
4293 | av->top = chunk_at_offset (oldp, nb); | |
4294 | set_head (av->top, (newsize - nb) | PREV_INUSE); | |
4295 | check_inuse_chunk (av, oldp); | |
4296 | return chunk2mem (oldp); | |
4297 | } | |
4298 | ||
4299 | /* Try to expand forward into next chunk; split off remainder below */ | |
4300 | else if (next != av->top && | |
4301 | !inuse (next) && | |
4302 | (unsigned long) (newsize = oldsize + nextsize) >= | |
4303 | (unsigned long) (nb)) | |
4304 | { | |
4305 | newp = oldp; | |
fff94fa2 | 4306 | unlink (av, next, bck, fwd); |
6c8dbf00 OB |
4307 | } |
4308 | ||
4309 | /* allocate, copy, free */ | |
4310 | else | |
4311 | { | |
4312 | newmem = _int_malloc (av, nb - MALLOC_ALIGN_MASK); | |
4313 | if (newmem == 0) | |
4314 | return 0; /* propagate failure */ | |
4315 | ||
4316 | newp = mem2chunk (newmem); | |
4317 | newsize = chunksize (newp); | |
4318 | ||
4319 | /* | |
4320 | Avoid copy if newp is next chunk after oldp. | |
4321 | */ | |
4322 | if (newp == next) | |
4323 | { | |
4324 | newsize += oldsize; | |
4325 | newp = oldp; | |
4326 | } | |
4327 | else | |
4328 | { | |
4329 | /* | |
4330 | Unroll copy of <= 36 bytes (72 if 8byte sizes) | |
4331 | We know that contents have an odd number of | |
4332 | INTERNAL_SIZE_T-sized words; minimally 3. | |
4333 | */ | |
4334 | ||
4335 | copysize = oldsize - SIZE_SZ; | |
4336 | s = (INTERNAL_SIZE_T *) (chunk2mem (oldp)); | |
4337 | d = (INTERNAL_SIZE_T *) (newmem); | |
4338 | ncopies = copysize / sizeof (INTERNAL_SIZE_T); | |
4339 | assert (ncopies >= 3); | |
4340 | ||
4341 | if (ncopies > 9) | |
4342 | memcpy (d, s, copysize); | |
4343 | ||
4344 | else | |
4345 | { | |
4346 | *(d + 0) = *(s + 0); | |
4347 | *(d + 1) = *(s + 1); | |
4348 | *(d + 2) = *(s + 2); | |
4349 | if (ncopies > 4) | |
4350 | { | |
4351 | *(d + 3) = *(s + 3); | |
4352 | *(d + 4) = *(s + 4); | |
4353 | if (ncopies > 6) | |
4354 | { | |
4355 | *(d + 5) = *(s + 5); | |
4356 | *(d + 6) = *(s + 6); | |
4357 | if (ncopies > 8) | |
4358 | { | |
4359 | *(d + 7) = *(s + 7); | |
4360 | *(d + 8) = *(s + 8); | |
4361 | } | |
4362 | } | |
4363 | } | |
4364 | } | |
4365 | ||
4366 | _int_free (av, oldp, 1); | |
4367 | check_inuse_chunk (av, newp); | |
4368 | return chunk2mem (newp); | |
4369 | } | |
4370 | } | |
fa8d436c | 4371 | } |
f65fd747 | 4372 | |
22a89187 | 4373 | /* If possible, free extra space in old or extended chunk */ |
f65fd747 | 4374 | |
6c8dbf00 | 4375 | assert ((unsigned long) (newsize) >= (unsigned long) (nb)); |
f65fd747 | 4376 | |
22a89187 | 4377 | remainder_size = newsize - nb; |
10dc2a90 | 4378 | |
6c8dbf00 OB |
4379 | if (remainder_size < MINSIZE) /* not enough extra to split off */ |
4380 | { | |
4381 | set_head_size (newp, newsize | (av != &main_arena ? NON_MAIN_ARENA : 0)); | |
4382 | set_inuse_bit_at_offset (newp, newsize); | |
4383 | } | |
4384 | else /* split remainder */ | |
4385 | { | |
4386 | remainder = chunk_at_offset (newp, nb); | |
4387 | set_head_size (newp, nb | (av != &main_arena ? NON_MAIN_ARENA : 0)); | |
4388 | set_head (remainder, remainder_size | PREV_INUSE | | |
4389 | (av != &main_arena ? NON_MAIN_ARENA : 0)); | |
4390 | /* Mark remainder as inuse so free() won't complain */ | |
4391 | set_inuse_bit_at_offset (remainder, remainder_size); | |
4392 | _int_free (av, remainder, 1); | |
4393 | } | |
22a89187 | 4394 | |
6c8dbf00 OB |
4395 | check_inuse_chunk (av, newp); |
4396 | return chunk2mem (newp); | |
fa8d436c UD |
4397 | } |
4398 | ||
4399 | /* | |
6c8dbf00 OB |
4400 | ------------------------------ memalign ------------------------------ |
4401 | */ | |
fa8d436c | 4402 | |
6c8dbf00 OB |
4403 | static void * |
4404 | _int_memalign (mstate av, size_t alignment, size_t bytes) | |
fa8d436c UD |
4405 | { |
4406 | INTERNAL_SIZE_T nb; /* padded request size */ | |
6c8dbf00 OB |
4407 | char *m; /* memory returned by malloc call */ |
4408 | mchunkptr p; /* corresponding chunk */ | |
4409 | char *brk; /* alignment point within p */ | |
4410 | mchunkptr newp; /* chunk to return */ | |
fa8d436c UD |
4411 | INTERNAL_SIZE_T newsize; /* its size */ |
4412 | INTERNAL_SIZE_T leadsize; /* leading space before alignment point */ | |
6c8dbf00 OB |
4413 | mchunkptr remainder; /* spare room at end to split off */ |
4414 | unsigned long remainder_size; /* its size */ | |
fa8d436c | 4415 | INTERNAL_SIZE_T size; |
f65fd747 | 4416 | |
f65fd747 | 4417 | |
f65fd747 | 4418 | |
6c8dbf00 | 4419 | checked_request2size (bytes, nb); |
fa8d436c UD |
4420 | |
4421 | /* | |
6c8dbf00 OB |
4422 | Strategy: find a spot within that chunk that meets the alignment |
4423 | request, and then possibly free the leading and trailing space. | |
4424 | */ | |
fa8d436c UD |
4425 | |
4426 | ||
4427 | /* Call malloc with worst case padding to hit alignment. */ | |
4428 | ||
6c8dbf00 OB |
4429 | m = (char *) (_int_malloc (av, nb + alignment + MINSIZE)); |
4430 | ||
4431 | if (m == 0) | |
4432 | return 0; /* propagate failure */ | |
4433 | ||
4434 | p = mem2chunk (m); | |
4435 | ||
4436 | if ((((unsigned long) (m)) % alignment) != 0) /* misaligned */ | |
4437 | ||
4438 | { /* | |
4439 | Find an aligned spot inside chunk. Since we need to give back | |
4440 | leading space in a chunk of at least MINSIZE, if the first | |
4441 | calculation places us at a spot with less than MINSIZE leader, | |
4442 | we can move to the next aligned spot -- we've allocated enough | |
4443 | total room so that this is always possible. | |
4444 | */ | |
4445 | brk = (char *) mem2chunk (((unsigned long) (m + alignment - 1)) & | |
4446 | - ((signed long) alignment)); | |
4447 | if ((unsigned long) (brk - (char *) (p)) < MINSIZE) | |
4448 | brk += alignment; | |
4449 | ||
4450 | newp = (mchunkptr) brk; | |
4451 | leadsize = brk - (char *) (p); | |
4452 | newsize = chunksize (p) - leadsize; | |
4453 | ||
4454 | /* For mmapped chunks, just adjust offset */ | |
4455 | if (chunk_is_mmapped (p)) | |
4456 | { | |
e9c4fe93 | 4457 | set_prev_size (newp, prev_size (p) + leadsize); |
6c8dbf00 OB |
4458 | set_head (newp, newsize | IS_MMAPPED); |
4459 | return chunk2mem (newp); | |
4460 | } | |
4461 | ||
4462 | /* Otherwise, give back leader, use the rest */ | |
4463 | set_head (newp, newsize | PREV_INUSE | | |
4464 | (av != &main_arena ? NON_MAIN_ARENA : 0)); | |
4465 | set_inuse_bit_at_offset (newp, newsize); | |
4466 | set_head_size (p, leadsize | (av != &main_arena ? NON_MAIN_ARENA : 0)); | |
4467 | _int_free (av, p, 1); | |
4468 | p = newp; | |
4469 | ||
4470 | assert (newsize >= nb && | |
4471 | (((unsigned long) (chunk2mem (p))) % alignment) == 0); | |
f65fd747 | 4472 | } |
f65fd747 | 4473 | |
f65fd747 | 4474 | /* Also give back spare room at the end */ |
6c8dbf00 OB |
4475 | if (!chunk_is_mmapped (p)) |
4476 | { | |
4477 | size = chunksize (p); | |
4478 | if ((unsigned long) (size) > (unsigned long) (nb + MINSIZE)) | |
4479 | { | |
4480 | remainder_size = size - nb; | |
4481 | remainder = chunk_at_offset (p, nb); | |
4482 | set_head (remainder, remainder_size | PREV_INUSE | | |
4483 | (av != &main_arena ? NON_MAIN_ARENA : 0)); | |
4484 | set_head_size (p, nb); | |
4485 | _int_free (av, remainder, 1); | |
4486 | } | |
fa8d436c | 4487 | } |
f65fd747 | 4488 | |
6c8dbf00 OB |
4489 | check_inuse_chunk (av, p); |
4490 | return chunk2mem (p); | |
f65fd747 UD |
4491 | } |
4492 | ||
f65fd747 | 4493 | |
fa8d436c | 4494 | /* |
6c8dbf00 OB |
4495 | ------------------------------ malloc_trim ------------------------------ |
4496 | */ | |
8a4b65b4 | 4497 | |
6c8dbf00 OB |
4498 | static int |
4499 | mtrim (mstate av, size_t pad) | |
f65fd747 | 4500 | { |
fff94fa2 SP |
4501 | /* Don't touch corrupt arenas. */ |
4502 | if (arena_is_corrupt (av)) | |
4503 | return 0; | |
4504 | ||
fa8d436c | 4505 | /* Ensure initialization/consolidation */ |
68631c8e UD |
4506 | malloc_consolidate (av); |
4507 | ||
6c8dbf00 | 4508 | const size_t ps = GLRO (dl_pagesize); |
68631c8e UD |
4509 | int psindex = bin_index (ps); |
4510 | const size_t psm1 = ps - 1; | |
4511 | ||
4512 | int result = 0; | |
4513 | for (int i = 1; i < NBINS; ++i) | |
4514 | if (i == 1 || i >= psindex) | |
4515 | { | |
6c8dbf00 | 4516 | mbinptr bin = bin_at (av, i); |
68631c8e | 4517 | |
6c8dbf00 OB |
4518 | for (mchunkptr p = last (bin); p != bin; p = p->bk) |
4519 | { | |
4520 | INTERNAL_SIZE_T size = chunksize (p); | |
68631c8e | 4521 | |
6c8dbf00 OB |
4522 | if (size > psm1 + sizeof (struct malloc_chunk)) |
4523 | { | |
4524 | /* See whether the chunk contains at least one unused page. */ | |
4525 | char *paligned_mem = (char *) (((uintptr_t) p | |
4526 | + sizeof (struct malloc_chunk) | |
4527 | + psm1) & ~psm1); | |
68631c8e | 4528 | |
6c8dbf00 OB |
4529 | assert ((char *) chunk2mem (p) + 4 * SIZE_SZ <= paligned_mem); |
4530 | assert ((char *) p + size > paligned_mem); | |
68631c8e | 4531 | |
6c8dbf00 OB |
4532 | /* This is the size we could potentially free. */ |
4533 | size -= paligned_mem - (char *) p; | |
68631c8e | 4534 | |
6c8dbf00 OB |
4535 | if (size > psm1) |
4536 | { | |
439bda32 | 4537 | #if MALLOC_DEBUG |
6c8dbf00 OB |
4538 | /* When debugging we simulate destroying the memory |
4539 | content. */ | |
4540 | memset (paligned_mem, 0x89, size & ~psm1); | |
68631c8e | 4541 | #endif |
6c8dbf00 | 4542 | __madvise (paligned_mem, size & ~psm1, MADV_DONTNEED); |
68631c8e | 4543 | |
6c8dbf00 OB |
4544 | result = 1; |
4545 | } | |
4546 | } | |
4547 | } | |
68631c8e | 4548 | } |
8a4b65b4 | 4549 | |
a9177ff5 | 4550 | #ifndef MORECORE_CANNOT_TRIM |
3b49edc0 | 4551 | return result | (av == &main_arena ? systrim (pad, av) : 0); |
6c8dbf00 | 4552 | |
8a4b65b4 | 4553 | #else |
68631c8e | 4554 | return result; |
f65fd747 | 4555 | #endif |
f65fd747 UD |
4556 | } |
4557 | ||
f65fd747 | 4558 | |
3b49edc0 | 4559 | int |
6c8dbf00 | 4560 | __malloc_trim (size_t s) |
3b49edc0 UD |
4561 | { |
4562 | int result = 0; | |
4563 | ||
6c8dbf00 | 4564 | if (__malloc_initialized < 0) |
3b49edc0 UD |
4565 | ptmalloc_init (); |
4566 | ||
4567 | mstate ar_ptr = &main_arena; | |
4568 | do | |
4569 | { | |
4bf5f222 | 4570 | __libc_lock_lock (ar_ptr->mutex); |
3b49edc0 | 4571 | result |= mtrim (ar_ptr, s); |
4bf5f222 | 4572 | __libc_lock_unlock (ar_ptr->mutex); |
3b49edc0 UD |
4573 | |
4574 | ar_ptr = ar_ptr->next; | |
4575 | } | |
4576 | while (ar_ptr != &main_arena); | |
4577 | ||
4578 | return result; | |
4579 | } | |
4580 | ||
4581 | ||
f65fd747 | 4582 | /* |
6c8dbf00 OB |
4583 | ------------------------- malloc_usable_size ------------------------- |
4584 | */ | |
f65fd747 | 4585 | |
3b49edc0 | 4586 | static size_t |
6c8dbf00 | 4587 | musable (void *mem) |
f65fd747 UD |
4588 | { |
4589 | mchunkptr p; | |
6c8dbf00 OB |
4590 | if (mem != 0) |
4591 | { | |
4592 | p = mem2chunk (mem); | |
4593 | ||
4594 | if (__builtin_expect (using_malloc_checking == 1, 0)) | |
4595 | return malloc_check_get_size (p); | |
4596 | ||
4597 | if (chunk_is_mmapped (p)) | |
073f8214 FW |
4598 | { |
4599 | if (DUMPED_MAIN_ARENA_CHUNK (p)) | |
4600 | return chunksize (p) - SIZE_SZ; | |
4601 | else | |
4602 | return chunksize (p) - 2 * SIZE_SZ; | |
4603 | } | |
6c8dbf00 OB |
4604 | else if (inuse (p)) |
4605 | return chunksize (p) - SIZE_SZ; | |
4606 | } | |
fa8d436c | 4607 | return 0; |
f65fd747 UD |
4608 | } |
4609 | ||
3b49edc0 UD |
4610 | |
4611 | size_t | |
6c8dbf00 | 4612 | __malloc_usable_size (void *m) |
3b49edc0 UD |
4613 | { |
4614 | size_t result; | |
4615 | ||
6c8dbf00 | 4616 | result = musable (m); |
3b49edc0 UD |
4617 | return result; |
4618 | } | |
4619 | ||
fa8d436c | 4620 | /* |
6c8dbf00 OB |
4621 | ------------------------------ mallinfo ------------------------------ |
4622 | Accumulate malloc statistics for arena AV into M. | |
4623 | */ | |
f65fd747 | 4624 | |
bedee953 | 4625 | static void |
6c8dbf00 | 4626 | int_mallinfo (mstate av, struct mallinfo *m) |
f65fd747 | 4627 | { |
6dd67bd5 | 4628 | size_t i; |
f65fd747 UD |
4629 | mbinptr b; |
4630 | mchunkptr p; | |
f65fd747 | 4631 | INTERNAL_SIZE_T avail; |
fa8d436c UD |
4632 | INTERNAL_SIZE_T fastavail; |
4633 | int nblocks; | |
4634 | int nfastblocks; | |
f65fd747 | 4635 | |
fa8d436c | 4636 | /* Ensure initialization */ |
6c8dbf00 OB |
4637 | if (av->top == 0) |
4638 | malloc_consolidate (av); | |
8a4b65b4 | 4639 | |
6c8dbf00 | 4640 | check_malloc_state (av); |
8a4b65b4 | 4641 | |
fa8d436c | 4642 | /* Account for top */ |
6c8dbf00 | 4643 | avail = chunksize (av->top); |
fa8d436c | 4644 | nblocks = 1; /* top always exists */ |
f65fd747 | 4645 | |
fa8d436c UD |
4646 | /* traverse fastbins */ |
4647 | nfastblocks = 0; | |
4648 | fastavail = 0; | |
4649 | ||
6c8dbf00 OB |
4650 | for (i = 0; i < NFASTBINS; ++i) |
4651 | { | |
4652 | for (p = fastbin (av, i); p != 0; p = p->fd) | |
4653 | { | |
4654 | ++nfastblocks; | |
4655 | fastavail += chunksize (p); | |
4656 | } | |
fa8d436c | 4657 | } |
fa8d436c UD |
4658 | |
4659 | avail += fastavail; | |
f65fd747 | 4660 | |
fa8d436c | 4661 | /* traverse regular bins */ |
6c8dbf00 OB |
4662 | for (i = 1; i < NBINS; ++i) |
4663 | { | |
4664 | b = bin_at (av, i); | |
4665 | for (p = last (b); p != b; p = p->bk) | |
4666 | { | |
4667 | ++nblocks; | |
4668 | avail += chunksize (p); | |
4669 | } | |
fa8d436c | 4670 | } |
f65fd747 | 4671 | |
bedee953 PP |
4672 | m->smblks += nfastblocks; |
4673 | m->ordblks += nblocks; | |
4674 | m->fordblks += avail; | |
4675 | m->uordblks += av->system_mem - avail; | |
4676 | m->arena += av->system_mem; | |
4677 | m->fsmblks += fastavail; | |
4678 | if (av == &main_arena) | |
4679 | { | |
4680 | m->hblks = mp_.n_mmaps; | |
4681 | m->hblkhd = mp_.mmapped_mem; | |
ca135f82 | 4682 | m->usmblks = 0; |
6c8dbf00 | 4683 | m->keepcost = chunksize (av->top); |
bedee953 | 4684 | } |
fa8d436c | 4685 | } |
f65fd747 | 4686 | |
3b49edc0 | 4687 | |
6c8dbf00 | 4688 | struct mallinfo |
9dd346ff | 4689 | __libc_mallinfo (void) |
3b49edc0 UD |
4690 | { |
4691 | struct mallinfo m; | |
bedee953 | 4692 | mstate ar_ptr; |
3b49edc0 | 4693 | |
6c8dbf00 | 4694 | if (__malloc_initialized < 0) |
3b49edc0 | 4695 | ptmalloc_init (); |
bedee953 | 4696 | |
6c8dbf00 | 4697 | memset (&m, 0, sizeof (m)); |
bedee953 | 4698 | ar_ptr = &main_arena; |
6c8dbf00 OB |
4699 | do |
4700 | { | |
4bf5f222 | 4701 | __libc_lock_lock (ar_ptr->mutex); |
6c8dbf00 | 4702 | int_mallinfo (ar_ptr, &m); |
4bf5f222 | 4703 | __libc_lock_unlock (ar_ptr->mutex); |
bedee953 | 4704 | |
6c8dbf00 OB |
4705 | ar_ptr = ar_ptr->next; |
4706 | } | |
4707 | while (ar_ptr != &main_arena); | |
bedee953 | 4708 | |
3b49edc0 UD |
4709 | return m; |
4710 | } | |
4711 | ||
fa8d436c | 4712 | /* |
6c8dbf00 OB |
4713 | ------------------------------ malloc_stats ------------------------------ |
4714 | */ | |
f65fd747 | 4715 | |
3b49edc0 | 4716 | void |
60d2f8f3 | 4717 | __malloc_stats (void) |
f65fd747 | 4718 | { |
8a4b65b4 | 4719 | int i; |
fa8d436c | 4720 | mstate ar_ptr; |
fa8d436c | 4721 | unsigned int in_use_b = mp_.mmapped_mem, system_b = in_use_b; |
8a4b65b4 | 4722 | |
6c8dbf00 | 4723 | if (__malloc_initialized < 0) |
a234e27d | 4724 | ptmalloc_init (); |
8dab36a1 UD |
4725 | _IO_flockfile (stderr); |
4726 | int old_flags2 = ((_IO_FILE *) stderr)->_flags2; | |
4727 | ((_IO_FILE *) stderr)->_flags2 |= _IO_FLAGS2_NOTCANCEL; | |
6c8dbf00 OB |
4728 | for (i = 0, ar_ptr = &main_arena;; i++) |
4729 | { | |
4730 | struct mallinfo mi; | |
4731 | ||
4732 | memset (&mi, 0, sizeof (mi)); | |
4bf5f222 | 4733 | __libc_lock_lock (ar_ptr->mutex); |
6c8dbf00 OB |
4734 | int_mallinfo (ar_ptr, &mi); |
4735 | fprintf (stderr, "Arena %d:\n", i); | |
4736 | fprintf (stderr, "system bytes = %10u\n", (unsigned int) mi.arena); | |
4737 | fprintf (stderr, "in use bytes = %10u\n", (unsigned int) mi.uordblks); | |
fa8d436c | 4738 | #if MALLOC_DEBUG > 1 |
6c8dbf00 OB |
4739 | if (i > 0) |
4740 | dump_heap (heap_for_ptr (top (ar_ptr))); | |
fa8d436c | 4741 | #endif |
6c8dbf00 OB |
4742 | system_b += mi.arena; |
4743 | in_use_b += mi.uordblks; | |
4bf5f222 | 4744 | __libc_lock_unlock (ar_ptr->mutex); |
6c8dbf00 OB |
4745 | ar_ptr = ar_ptr->next; |
4746 | if (ar_ptr == &main_arena) | |
4747 | break; | |
4748 | } | |
4749 | fprintf (stderr, "Total (incl. mmap):\n"); | |
4750 | fprintf (stderr, "system bytes = %10u\n", system_b); | |
4751 | fprintf (stderr, "in use bytes = %10u\n", in_use_b); | |
4752 | fprintf (stderr, "max mmap regions = %10u\n", (unsigned int) mp_.max_n_mmaps); | |
4753 | fprintf (stderr, "max mmap bytes = %10lu\n", | |
4754 | (unsigned long) mp_.max_mmapped_mem); | |
8dab36a1 UD |
4755 | ((_IO_FILE *) stderr)->_flags2 |= old_flags2; |
4756 | _IO_funlockfile (stderr); | |
f65fd747 UD |
4757 | } |
4758 | ||
f65fd747 UD |
4759 | |
4760 | /* | |
6c8dbf00 OB |
4761 | ------------------------------ mallopt ------------------------------ |
4762 | */ | |
be7991c0 SP |
4763 | static inline int |
4764 | __always_inline | |
4765 | do_set_trim_threshold (size_t value) | |
4766 | { | |
4767 | LIBC_PROBE (memory_mallopt_trim_threshold, 3, value, mp_.trim_threshold, | |
4768 | mp_.no_dyn_threshold); | |
4769 | mp_.trim_threshold = value; | |
4770 | mp_.no_dyn_threshold = 1; | |
4771 | return 1; | |
4772 | } | |
4773 | ||
4774 | static inline int | |
4775 | __always_inline | |
4776 | do_set_top_pad (size_t value) | |
4777 | { | |
4778 | LIBC_PROBE (memory_mallopt_top_pad, 3, value, mp_.top_pad, | |
4779 | mp_.no_dyn_threshold); | |
4780 | mp_.top_pad = value; | |
4781 | mp_.no_dyn_threshold = 1; | |
4782 | return 1; | |
4783 | } | |
4784 | ||
4785 | static inline int | |
4786 | __always_inline | |
4787 | do_set_mmap_threshold (size_t value) | |
4788 | { | |
4789 | /* Forbid setting the threshold too high. */ | |
4790 | if (value <= HEAP_MAX_SIZE / 2) | |
4791 | { | |
4792 | LIBC_PROBE (memory_mallopt_mmap_threshold, 3, value, mp_.mmap_threshold, | |
4793 | mp_.no_dyn_threshold); | |
4794 | mp_.mmap_threshold = value; | |
4795 | mp_.no_dyn_threshold = 1; | |
4796 | return 1; | |
4797 | } | |
4798 | return 0; | |
4799 | } | |
4800 | ||
4801 | static inline int | |
4802 | __always_inline | |
4803 | do_set_mmaps_max (int32_t value) | |
4804 | { | |
4805 | LIBC_PROBE (memory_mallopt_mmap_max, 3, value, mp_.n_mmaps_max, | |
4806 | mp_.no_dyn_threshold); | |
4807 | mp_.n_mmaps_max = value; | |
4808 | mp_.no_dyn_threshold = 1; | |
4809 | return 1; | |
4810 | } | |
4811 | ||
4812 | static inline int | |
4813 | __always_inline | |
4814 | do_set_mallopt_check (int32_t value) | |
4815 | { | |
4816 | LIBC_PROBE (memory_mallopt_check_action, 2, value, check_action); | |
4817 | check_action = value; | |
4818 | return 1; | |
4819 | } | |
4820 | ||
4821 | static inline int | |
4822 | __always_inline | |
4823 | do_set_perturb_byte (int32_t value) | |
4824 | { | |
4825 | LIBC_PROBE (memory_mallopt_perturb, 2, value, perturb_byte); | |
4826 | perturb_byte = value; | |
4827 | return 1; | |
4828 | } | |
4829 | ||
4830 | static inline int | |
4831 | __always_inline | |
4832 | do_set_arena_test (size_t value) | |
4833 | { | |
4834 | LIBC_PROBE (memory_mallopt_arena_test, 2, value, mp_.arena_test); | |
4835 | mp_.arena_test = value; | |
4836 | return 1; | |
4837 | } | |
4838 | ||
4839 | static inline int | |
4840 | __always_inline | |
4841 | do_set_arena_max (size_t value) | |
4842 | { | |
4843 | LIBC_PROBE (memory_mallopt_arena_max, 2, value, mp_.arena_max); | |
4844 | mp_.arena_max = value; | |
4845 | return 1; | |
4846 | } | |
4847 | ||
f65fd747 | 4848 | |
6c8dbf00 OB |
4849 | int |
4850 | __libc_mallopt (int param_number, int value) | |
f65fd747 | 4851 | { |
fa8d436c UD |
4852 | mstate av = &main_arena; |
4853 | int res = 1; | |
f65fd747 | 4854 | |
6c8dbf00 | 4855 | if (__malloc_initialized < 0) |
0cb71e02 | 4856 | ptmalloc_init (); |
4bf5f222 | 4857 | __libc_lock_lock (av->mutex); |
fa8d436c | 4858 | /* Ensure initialization/consolidation */ |
6c8dbf00 | 4859 | malloc_consolidate (av); |
2f6d1f1b | 4860 | |
3ea5be54 AO |
4861 | LIBC_PROBE (memory_mallopt, 2, param_number, value); |
4862 | ||
6c8dbf00 OB |
4863 | switch (param_number) |
4864 | { | |
4865 | case M_MXFAST: | |
4866 | if (value >= 0 && value <= MAX_FAST_SIZE) | |
4867 | { | |
4868 | LIBC_PROBE (memory_mallopt_mxfast, 2, value, get_max_fast ()); | |
4869 | set_max_fast (value); | |
4870 | } | |
4871 | else | |
4872 | res = 0; | |
4873 | break; | |
4874 | ||
4875 | case M_TRIM_THRESHOLD: | |
be7991c0 | 4876 | do_set_trim_threshold (value); |
6c8dbf00 OB |
4877 | break; |
4878 | ||
4879 | case M_TOP_PAD: | |
be7991c0 | 4880 | do_set_top_pad (value); |
6c8dbf00 OB |
4881 | break; |
4882 | ||
4883 | case M_MMAP_THRESHOLD: | |
be7991c0 | 4884 | res = do_set_mmap_threshold (value); |
6c8dbf00 OB |
4885 | break; |
4886 | ||
4887 | case M_MMAP_MAX: | |
be7991c0 | 4888 | do_set_mmaps_max (value); |
6c8dbf00 OB |
4889 | break; |
4890 | ||
4891 | case M_CHECK_ACTION: | |
be7991c0 | 4892 | do_set_mallopt_check (value); |
6c8dbf00 OB |
4893 | break; |
4894 | ||
4895 | case M_PERTURB: | |
be7991c0 | 4896 | do_set_perturb_byte (value); |
6c8dbf00 OB |
4897 | break; |
4898 | ||
4899 | case M_ARENA_TEST: | |
4900 | if (value > 0) | |
be7991c0 | 4901 | do_set_arena_test (value); |
6c8dbf00 OB |
4902 | break; |
4903 | ||
4904 | case M_ARENA_MAX: | |
4905 | if (value > 0) | |
62222284 | 4906 | do_set_arena_max (value); |
6c8dbf00 OB |
4907 | break; |
4908 | } | |
4bf5f222 | 4909 | __libc_lock_unlock (av->mutex); |
fa8d436c | 4910 | return res; |
b22fc5f5 | 4911 | } |
3b49edc0 | 4912 | libc_hidden_def (__libc_mallopt) |
b22fc5f5 | 4913 | |
10dc2a90 | 4914 | |
a9177ff5 | 4915 | /* |
6c8dbf00 OB |
4916 | -------------------- Alternative MORECORE functions -------------------- |
4917 | */ | |
10dc2a90 | 4918 | |
b22fc5f5 | 4919 | |
fa8d436c | 4920 | /* |
6c8dbf00 | 4921 | General Requirements for MORECORE. |
b22fc5f5 | 4922 | |
6c8dbf00 | 4923 | The MORECORE function must have the following properties: |
b22fc5f5 | 4924 | |
6c8dbf00 | 4925 | If MORECORE_CONTIGUOUS is false: |
10dc2a90 | 4926 | |
6c8dbf00 | 4927 | * MORECORE must allocate in multiples of pagesize. It will |
fa8d436c | 4928 | only be called with arguments that are multiples of pagesize. |
10dc2a90 | 4929 | |
6c8dbf00 | 4930 | * MORECORE(0) must return an address that is at least |
fa8d436c | 4931 | MALLOC_ALIGNMENT aligned. (Page-aligning always suffices.) |
10dc2a90 | 4932 | |
6c8dbf00 | 4933 | else (i.e. If MORECORE_CONTIGUOUS is true): |
10dc2a90 | 4934 | |
6c8dbf00 | 4935 | * Consecutive calls to MORECORE with positive arguments |
fa8d436c UD |
4936 | return increasing addresses, indicating that space has been |
4937 | contiguously extended. | |
10dc2a90 | 4938 | |
6c8dbf00 | 4939 | * MORECORE need not allocate in multiples of pagesize. |
fa8d436c | 4940 | Calls to MORECORE need not have args of multiples of pagesize. |
10dc2a90 | 4941 | |
6c8dbf00 | 4942 | * MORECORE need not page-align. |
10dc2a90 | 4943 | |
6c8dbf00 | 4944 | In either case: |
10dc2a90 | 4945 | |
6c8dbf00 | 4946 | * MORECORE may allocate more memory than requested. (Or even less, |
fa8d436c | 4947 | but this will generally result in a malloc failure.) |
10dc2a90 | 4948 | |
6c8dbf00 | 4949 | * MORECORE must not allocate memory when given argument zero, but |
fa8d436c UD |
4950 | instead return one past the end address of memory from previous |
4951 | nonzero call. This malloc does NOT call MORECORE(0) | |
4952 | until at least one call with positive arguments is made, so | |
4953 | the initial value returned is not important. | |
10dc2a90 | 4954 | |
6c8dbf00 | 4955 | * Even though consecutive calls to MORECORE need not return contiguous |
fa8d436c UD |
4956 | addresses, it must be OK for malloc'ed chunks to span multiple |
4957 | regions in those cases where they do happen to be contiguous. | |
10dc2a90 | 4958 | |
6c8dbf00 | 4959 | * MORECORE need not handle negative arguments -- it may instead |
fa8d436c UD |
4960 | just return MORECORE_FAILURE when given negative arguments. |
4961 | Negative arguments are always multiples of pagesize. MORECORE | |
4962 | must not misinterpret negative args as large positive unsigned | |
4963 | args. You can suppress all such calls from even occurring by defining | |
4964 | MORECORE_CANNOT_TRIM, | |
10dc2a90 | 4965 | |
6c8dbf00 OB |
4966 | There is some variation across systems about the type of the |
4967 | argument to sbrk/MORECORE. If size_t is unsigned, then it cannot | |
4968 | actually be size_t, because sbrk supports negative args, so it is | |
4969 | normally the signed type of the same width as size_t (sometimes | |
4970 | declared as "intptr_t", and sometimes "ptrdiff_t"). It doesn't much | |
4971 | matter though. Internally, we use "long" as arguments, which should | |
4972 | work across all reasonable possibilities. | |
4973 | ||
4974 | Additionally, if MORECORE ever returns failure for a positive | |
4975 | request, then mmap is used as a noncontiguous system allocator. This | |
4976 | is a useful backup strategy for systems with holes in address spaces | |
4977 | -- in this case sbrk cannot contiguously expand the heap, but mmap | |
4978 | may be able to map noncontiguous space. | |
4979 | ||
4980 | If you'd like mmap to ALWAYS be used, you can define MORECORE to be | |
4981 | a function that always returns MORECORE_FAILURE. | |
4982 | ||
4983 | If you are using this malloc with something other than sbrk (or its | |
4984 | emulation) to supply memory regions, you probably want to set | |
4985 | MORECORE_CONTIGUOUS as false. As an example, here is a custom | |
4986 | allocator kindly contributed for pre-OSX macOS. It uses virtually | |
4987 | but not necessarily physically contiguous non-paged memory (locked | |
4988 | in, present and won't get swapped out). You can use it by | |
4989 | uncommenting this section, adding some #includes, and setting up the | |
4990 | appropriate defines above: | |
4991 | ||
4992 | *#define MORECORE osMoreCore | |
4993 | *#define MORECORE_CONTIGUOUS 0 | |
4994 | ||
4995 | There is also a shutdown routine that should somehow be called for | |
4996 | cleanup upon program exit. | |
4997 | ||
4998 | *#define MAX_POOL_ENTRIES 100 | |
4999 | *#define MINIMUM_MORECORE_SIZE (64 * 1024) | |
5000 | static int next_os_pool; | |
5001 | void *our_os_pools[MAX_POOL_ENTRIES]; | |
5002 | ||
5003 | void *osMoreCore(int size) | |
5004 | { | |
fa8d436c UD |
5005 | void *ptr = 0; |
5006 | static void *sbrk_top = 0; | |
ca34d7a7 | 5007 | |
fa8d436c UD |
5008 | if (size > 0) |
5009 | { | |
5010 | if (size < MINIMUM_MORECORE_SIZE) | |
6c8dbf00 | 5011 | size = MINIMUM_MORECORE_SIZE; |
fa8d436c | 5012 | if (CurrentExecutionLevel() == kTaskLevel) |
6c8dbf00 | 5013 | ptr = PoolAllocateResident(size + RM_PAGE_SIZE, 0); |
fa8d436c UD |
5014 | if (ptr == 0) |
5015 | { | |
6c8dbf00 | 5016 | return (void *) MORECORE_FAILURE; |
fa8d436c UD |
5017 | } |
5018 | // save ptrs so they can be freed during cleanup | |
5019 | our_os_pools[next_os_pool] = ptr; | |
5020 | next_os_pool++; | |
5021 | ptr = (void *) ((((unsigned long) ptr) + RM_PAGE_MASK) & ~RM_PAGE_MASK); | |
5022 | sbrk_top = (char *) ptr + size; | |
5023 | return ptr; | |
5024 | } | |
5025 | else if (size < 0) | |
5026 | { | |
5027 | // we don't currently support shrink behavior | |
5028 | return (void *) MORECORE_FAILURE; | |
5029 | } | |
5030 | else | |
5031 | { | |
5032 | return sbrk_top; | |
431c33c0 | 5033 | } |
6c8dbf00 | 5034 | } |
ca34d7a7 | 5035 | |
6c8dbf00 OB |
5036 | // cleanup any allocated memory pools |
5037 | // called as last thing before shutting down driver | |
ca34d7a7 | 5038 | |
6c8dbf00 OB |
5039 | void osCleanupMem(void) |
5040 | { | |
fa8d436c | 5041 | void **ptr; |
ca34d7a7 | 5042 | |
fa8d436c UD |
5043 | for (ptr = our_os_pools; ptr < &our_os_pools[MAX_POOL_ENTRIES]; ptr++) |
5044 | if (*ptr) | |
5045 | { | |
6c8dbf00 OB |
5046 | PoolDeallocate(*ptr); |
5047 | * ptr = 0; | |
fa8d436c | 5048 | } |
6c8dbf00 | 5049 | } |
ee74a442 | 5050 | |
6c8dbf00 | 5051 | */ |
f65fd747 | 5052 | |
7e3be507 | 5053 | |
3e030bd5 UD |
5054 | /* Helper code. */ |
5055 | ||
ae7f5313 UD |
5056 | extern char **__libc_argv attribute_hidden; |
5057 | ||
3e030bd5 | 5058 | static void |
fff94fa2 | 5059 | malloc_printerr (int action, const char *str, void *ptr, mstate ar_ptr) |
3e030bd5 | 5060 | { |
fff94fa2 SP |
5061 | /* Avoid using this arena in future. We do not attempt to synchronize this |
5062 | with anything else because we minimally want to ensure that __libc_message | |
5063 | gets its resources safely without stumbling on the current corruption. */ | |
5064 | if (ar_ptr) | |
5065 | set_arena_corrupt (ar_ptr); | |
5066 | ||
553cc5f9 UD |
5067 | if ((action & 5) == 5) |
5068 | __libc_message (action & 2, "%s\n", str); | |
5069 | else if (action & 1) | |
3e030bd5 | 5070 | { |
a9055cab | 5071 | char buf[2 * sizeof (uintptr_t) + 1]; |
3e030bd5 | 5072 | |
a9055cab UD |
5073 | buf[sizeof (buf) - 1] = '\0'; |
5074 | char *cp = _itoa_word ((uintptr_t) ptr, &buf[sizeof (buf) - 1], 16, 0); | |
5075 | while (cp > buf) | |
6c8dbf00 | 5076 | *--cp = '0'; |
a9055cab | 5077 | |
bb9510dc | 5078 | __libc_message (action & 2, "*** Error in `%s': %s: 0x%s ***\n", |
6c8dbf00 | 5079 | __libc_argv[0] ? : "<unknown>", str, cp); |
3e030bd5 | 5080 | } |
a9055cab | 5081 | else if (action & 2) |
3e030bd5 UD |
5082 | abort (); |
5083 | } | |
5084 | ||
a204dbb2 UD |
5085 | /* We need a wrapper function for one of the additions of POSIX. */ |
5086 | int | |
5087 | __posix_memalign (void **memptr, size_t alignment, size_t size) | |
5088 | { | |
5089 | void *mem; | |
5090 | ||
5091 | /* Test whether the SIZE argument is valid. It must be a power of | |
5092 | two multiple of sizeof (void *). */ | |
de02bd05 | 5093 | if (alignment % sizeof (void *) != 0 |
fc56e970 | 5094 | || !powerof2 (alignment / sizeof (void *)) |
de02bd05 | 5095 | || alignment == 0) |
a204dbb2 UD |
5096 | return EINVAL; |
5097 | ||
10ad46bc OB |
5098 | |
5099 | void *address = RETURN_ADDRESS (0); | |
5100 | mem = _mid_memalign (alignment, size, address); | |
a204dbb2 | 5101 | |
6c8dbf00 OB |
5102 | if (mem != NULL) |
5103 | { | |
5104 | *memptr = mem; | |
5105 | return 0; | |
5106 | } | |
a204dbb2 UD |
5107 | |
5108 | return ENOMEM; | |
5109 | } | |
5110 | weak_alias (__posix_memalign, posix_memalign) | |
5111 | ||
20c13899 OB |
5112 | |
5113 | int | |
c52ff39e | 5114 | __malloc_info (int options, FILE *fp) |
bb066545 | 5115 | { |
20c13899 OB |
5116 | /* For now, at least. */ |
5117 | if (options != 0) | |
5118 | return EINVAL; | |
bb066545 | 5119 | |
20c13899 OB |
5120 | int n = 0; |
5121 | size_t total_nblocks = 0; | |
5122 | size_t total_nfastblocks = 0; | |
5123 | size_t total_avail = 0; | |
5124 | size_t total_fastavail = 0; | |
5125 | size_t total_system = 0; | |
5126 | size_t total_max_system = 0; | |
5127 | size_t total_aspace = 0; | |
5128 | size_t total_aspace_mprotect = 0; | |
bb066545 | 5129 | |
6c8dbf00 | 5130 | |
6c8dbf00 | 5131 | |
987c0269 OB |
5132 | if (__malloc_initialized < 0) |
5133 | ptmalloc_init (); | |
bb066545 | 5134 | |
987c0269 | 5135 | fputs ("<malloc version=\"1\">\n", fp); |
bb066545 | 5136 | |
987c0269 OB |
5137 | /* Iterate over all arenas currently in use. */ |
5138 | mstate ar_ptr = &main_arena; | |
5139 | do | |
5140 | { | |
5141 | fprintf (fp, "<heap nr=\"%d\">\n<sizes>\n", n++); | |
8b35e35d | 5142 | |
987c0269 OB |
5143 | size_t nblocks = 0; |
5144 | size_t nfastblocks = 0; | |
5145 | size_t avail = 0; | |
5146 | size_t fastavail = 0; | |
5147 | struct | |
5148 | { | |
5149 | size_t from; | |
5150 | size_t to; | |
5151 | size_t total; | |
5152 | size_t count; | |
5153 | } sizes[NFASTBINS + NBINS - 1]; | |
5154 | #define nsizes (sizeof (sizes) / sizeof (sizes[0])) | |
6c8dbf00 | 5155 | |
4bf5f222 | 5156 | __libc_lock_lock (ar_ptr->mutex); |
bb066545 | 5157 | |
987c0269 OB |
5158 | for (size_t i = 0; i < NFASTBINS; ++i) |
5159 | { | |
5160 | mchunkptr p = fastbin (ar_ptr, i); | |
5161 | if (p != NULL) | |
5162 | { | |
5163 | size_t nthissize = 0; | |
5164 | size_t thissize = chunksize (p); | |
5165 | ||
5166 | while (p != NULL) | |
5167 | { | |
5168 | ++nthissize; | |
5169 | p = p->fd; | |
5170 | } | |
5171 | ||
5172 | fastavail += nthissize * thissize; | |
5173 | nfastblocks += nthissize; | |
5174 | sizes[i].from = thissize - (MALLOC_ALIGNMENT - 1); | |
5175 | sizes[i].to = thissize; | |
5176 | sizes[i].count = nthissize; | |
5177 | } | |
5178 | else | |
5179 | sizes[i].from = sizes[i].to = sizes[i].count = 0; | |
bb066545 | 5180 | |
987c0269 OB |
5181 | sizes[i].total = sizes[i].count * sizes[i].to; |
5182 | } | |
bb066545 | 5183 | |
bb066545 | 5184 | |
987c0269 OB |
5185 | mbinptr bin; |
5186 | struct malloc_chunk *r; | |
bb066545 | 5187 | |
987c0269 OB |
5188 | for (size_t i = 1; i < NBINS; ++i) |
5189 | { | |
5190 | bin = bin_at (ar_ptr, i); | |
5191 | r = bin->fd; | |
5192 | sizes[NFASTBINS - 1 + i].from = ~((size_t) 0); | |
5193 | sizes[NFASTBINS - 1 + i].to = sizes[NFASTBINS - 1 + i].total | |
5194 | = sizes[NFASTBINS - 1 + i].count = 0; | |
5195 | ||
5196 | if (r != NULL) | |
5197 | while (r != bin) | |
5198 | { | |
e9c4fe93 | 5199 | size_t r_size = chunksize_nomask (r); |
987c0269 | 5200 | ++sizes[NFASTBINS - 1 + i].count; |
e9c4fe93 | 5201 | sizes[NFASTBINS - 1 + i].total += r_size; |
987c0269 | 5202 | sizes[NFASTBINS - 1 + i].from |
e9c4fe93 | 5203 | = MIN (sizes[NFASTBINS - 1 + i].from, r_size); |
987c0269 | 5204 | sizes[NFASTBINS - 1 + i].to = MAX (sizes[NFASTBINS - 1 + i].to, |
e9c4fe93 | 5205 | r_size); |
987c0269 OB |
5206 | |
5207 | r = r->fd; | |
5208 | } | |
5209 | ||
5210 | if (sizes[NFASTBINS - 1 + i].count == 0) | |
5211 | sizes[NFASTBINS - 1 + i].from = 0; | |
5212 | nblocks += sizes[NFASTBINS - 1 + i].count; | |
5213 | avail += sizes[NFASTBINS - 1 + i].total; | |
5214 | } | |
bb066545 | 5215 | |
4bf5f222 | 5216 | __libc_lock_unlock (ar_ptr->mutex); |
da2d2fb6 | 5217 | |
987c0269 OB |
5218 | total_nfastblocks += nfastblocks; |
5219 | total_fastavail += fastavail; | |
0588a9cb | 5220 | |
987c0269 OB |
5221 | total_nblocks += nblocks; |
5222 | total_avail += avail; | |
0588a9cb | 5223 | |
987c0269 OB |
5224 | for (size_t i = 0; i < nsizes; ++i) |
5225 | if (sizes[i].count != 0 && i != NFASTBINS) | |
5226 | fprintf (fp, " \ | |
5227 | <size from=\"%zu\" to=\"%zu\" total=\"%zu\" count=\"%zu\"/>\n", | |
5228 | sizes[i].from, sizes[i].to, sizes[i].total, sizes[i].count); | |
fdfd175d | 5229 | |
987c0269 OB |
5230 | if (sizes[NFASTBINS].count != 0) |
5231 | fprintf (fp, "\ | |
5232 | <unsorted from=\"%zu\" to=\"%zu\" total=\"%zu\" count=\"%zu\"/>\n", | |
5233 | sizes[NFASTBINS].from, sizes[NFASTBINS].to, | |
5234 | sizes[NFASTBINS].total, sizes[NFASTBINS].count); | |
fdfd175d | 5235 | |
987c0269 OB |
5236 | total_system += ar_ptr->system_mem; |
5237 | total_max_system += ar_ptr->max_system_mem; | |
bb066545 | 5238 | |
987c0269 OB |
5239 | fprintf (fp, |
5240 | "</sizes>\n<total type=\"fast\" count=\"%zu\" size=\"%zu\"/>\n" | |
5241 | "<total type=\"rest\" count=\"%zu\" size=\"%zu\"/>\n" | |
5242 | "<system type=\"current\" size=\"%zu\"/>\n" | |
5243 | "<system type=\"max\" size=\"%zu\"/>\n", | |
5244 | nfastblocks, fastavail, nblocks, avail, | |
5245 | ar_ptr->system_mem, ar_ptr->max_system_mem); | |
346bc35c | 5246 | |
987c0269 OB |
5247 | if (ar_ptr != &main_arena) |
5248 | { | |
5249 | heap_info *heap = heap_for_ptr (top (ar_ptr)); | |
5250 | fprintf (fp, | |
5251 | "<aspace type=\"total\" size=\"%zu\"/>\n" | |
5252 | "<aspace type=\"mprotect\" size=\"%zu\"/>\n", | |
5253 | heap->size, heap->mprotect_size); | |
5254 | total_aspace += heap->size; | |
5255 | total_aspace_mprotect += heap->mprotect_size; | |
5256 | } | |
5257 | else | |
5258 | { | |
5259 | fprintf (fp, | |
5260 | "<aspace type=\"total\" size=\"%zu\"/>\n" | |
5261 | "<aspace type=\"mprotect\" size=\"%zu\"/>\n", | |
5262 | ar_ptr->system_mem, ar_ptr->system_mem); | |
5263 | total_aspace += ar_ptr->system_mem; | |
5264 | total_aspace_mprotect += ar_ptr->system_mem; | |
5265 | } | |
bb066545 | 5266 | |
987c0269 | 5267 | fputs ("</heap>\n", fp); |
bb066545 UD |
5268 | ar_ptr = ar_ptr->next; |
5269 | } | |
5270 | while (ar_ptr != &main_arena); | |
5271 | ||
5272 | fprintf (fp, | |
62a58816 SP |
5273 | "<total type=\"fast\" count=\"%zu\" size=\"%zu\"/>\n" |
5274 | "<total type=\"rest\" count=\"%zu\" size=\"%zu\"/>\n" | |
9fa76613 | 5275 | "<total type=\"mmap\" count=\"%d\" size=\"%zu\"/>\n" |
62a58816 SP |
5276 | "<system type=\"current\" size=\"%zu\"/>\n" |
5277 | "<system type=\"max\" size=\"%zu\"/>\n" | |
5278 | "<aspace type=\"total\" size=\"%zu\"/>\n" | |
5279 | "<aspace type=\"mprotect\" size=\"%zu\"/>\n" | |
5280 | "</malloc>\n", | |
5281 | total_nfastblocks, total_fastavail, total_nblocks, total_avail, | |
4d653a59 | 5282 | mp_.n_mmaps, mp_.mmapped_mem, |
62a58816 SP |
5283 | total_system, total_max_system, |
5284 | total_aspace, total_aspace_mprotect); | |
bb066545 UD |
5285 | |
5286 | return 0; | |
5287 | } | |
c52ff39e | 5288 | weak_alias (__malloc_info, malloc_info) |
bb066545 UD |
5289 | |
5290 | ||
eba19d2b | 5291 | strong_alias (__libc_calloc, __calloc) weak_alias (__libc_calloc, calloc) |
eba19d2b UD |
5292 | strong_alias (__libc_free, __free) strong_alias (__libc_free, free) |
5293 | strong_alias (__libc_malloc, __malloc) strong_alias (__libc_malloc, malloc) | |
5294 | strong_alias (__libc_memalign, __memalign) | |
5295 | weak_alias (__libc_memalign, memalign) | |
5296 | strong_alias (__libc_realloc, __realloc) strong_alias (__libc_realloc, realloc) | |
5297 | strong_alias (__libc_valloc, __valloc) weak_alias (__libc_valloc, valloc) | |
5298 | strong_alias (__libc_pvalloc, __pvalloc) weak_alias (__libc_pvalloc, pvalloc) | |
5299 | strong_alias (__libc_mallinfo, __mallinfo) | |
5300 | weak_alias (__libc_mallinfo, mallinfo) | |
5301 | strong_alias (__libc_mallopt, __mallopt) weak_alias (__libc_mallopt, mallopt) | |
7e3be507 UD |
5302 | |
5303 | weak_alias (__malloc_stats, malloc_stats) | |
5304 | weak_alias (__malloc_usable_size, malloc_usable_size) | |
5305 | weak_alias (__malloc_trim, malloc_trim) | |
7e3be507 | 5306 | |
025b33ae FW |
5307 | #if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_26) |
5308 | compat_symbol (libc, __libc_free, cfree, GLIBC_2_0); | |
5309 | #endif | |
f65fd747 | 5310 | |
fa8d436c | 5311 | /* ------------------------------------------------------------ |
6c8dbf00 | 5312 | History: |
f65fd747 | 5313 | |
6c8dbf00 | 5314 | [see ftp://g.oswego.edu/pub/misc/malloc.c for the history of dlmalloc] |
f65fd747 | 5315 | |
6c8dbf00 | 5316 | */ |
fa8d436c UD |
5317 | /* |
5318 | * Local variables: | |
5319 | * c-basic-offset: 2 | |
5320 | * End: | |
5321 | */ |