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56137dbc | 1 | /* Malloc implementation for multiple threads without lock contention. |
04277e02 | 2 | Copyright (C) 1996-2019 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> |
406e7a0a | 226 | #include <assert.h> |
f65fd747 | 227 | |
66274218 AJ |
228 | #include <shlib-compat.h> |
229 | ||
5d78bb43 UD |
230 | /* For uintptr_t. */ |
231 | #include <stdint.h> | |
f65fd747 | 232 | |
3e030bd5 UD |
233 | /* For va_arg, va_start, va_end. */ |
234 | #include <stdarg.h> | |
235 | ||
070906ff RM |
236 | /* For MIN, MAX, powerof2. */ |
237 | #include <sys/param.h> | |
238 | ||
ca6be165 | 239 | /* For ALIGN_UP et. al. */ |
9090848d | 240 | #include <libc-pointer-arith.h> |
8a35c3fe | 241 | |
d5c3fafc DD |
242 | /* For DIAG_PUSH/POP_NEEDS_COMMENT et al. */ |
243 | #include <libc-diag.h> | |
244 | ||
29d79486 | 245 | #include <malloc/malloc-internal.h> |
c0f62c56 | 246 | |
6d43de4b WD |
247 | /* For SINGLE_THREAD_P. */ |
248 | #include <sysdep-cancel.h> | |
249 | ||
fa8d436c UD |
250 | /* |
251 | Debugging: | |
252 | ||
253 | Because freed chunks may be overwritten with bookkeeping fields, this | |
254 | malloc will often die when freed memory is overwritten by user | |
255 | programs. This can be very effective (albeit in an annoying way) | |
256 | in helping track down dangling pointers. | |
257 | ||
258 | If you compile with -DMALLOC_DEBUG, a number of assertion checks are | |
259 | enabled that will catch more memory errors. You probably won't be | |
260 | able to make much sense of the actual assertion errors, but they | |
261 | should help you locate incorrectly overwritten memory. The checking | |
262 | is fairly extensive, and will slow down execution | |
263 | noticeably. Calling malloc_stats or mallinfo with MALLOC_DEBUG set | |
264 | will attempt to check every non-mmapped allocated and free chunk in | |
265 | the course of computing the summmaries. (By nature, mmapped regions | |
266 | cannot be checked very much automatically.) | |
267 | ||
268 | Setting MALLOC_DEBUG may also be helpful if you are trying to modify | |
269 | this code. The assertions in the check routines spell out in more | |
270 | detail the assumptions and invariants underlying the algorithms. | |
271 | ||
272 | Setting MALLOC_DEBUG does NOT provide an automated mechanism for | |
273 | checking that all accesses to malloced memory stay within their | |
274 | bounds. However, there are several add-ons and adaptations of this | |
275 | or other mallocs available that do this. | |
f65fd747 UD |
276 | */ |
277 | ||
439bda32 WN |
278 | #ifndef MALLOC_DEBUG |
279 | #define MALLOC_DEBUG 0 | |
280 | #endif | |
281 | ||
406e7a0a ST |
282 | #ifndef NDEBUG |
283 | # define __assert_fail(assertion, file, line, function) \ | |
284 | __malloc_assert(assertion, file, line, function) | |
72f90263 UD |
285 | |
286 | extern const char *__progname; | |
287 | ||
288 | static void | |
289 | __malloc_assert (const char *assertion, const char *file, unsigned int line, | |
290 | const char *function) | |
291 | { | |
292 | (void) __fxprintf (NULL, "%s%s%s:%u: %s%sAssertion `%s' failed.\n", | |
293 | __progname, __progname[0] ? ": " : "", | |
294 | file, line, | |
295 | function ? function : "", function ? ": " : "", | |
296 | assertion); | |
297 | fflush (stderr); | |
298 | abort (); | |
299 | } | |
300 | #endif | |
f65fd747 | 301 | |
d5c3fafc DD |
302 | #if USE_TCACHE |
303 | /* We want 64 entries. This is an arbitrary limit, which tunables can reduce. */ | |
304 | # define TCACHE_MAX_BINS 64 | |
305 | # define MAX_TCACHE_SIZE tidx2usize (TCACHE_MAX_BINS-1) | |
306 | ||
307 | /* Only used to pre-fill the tunables. */ | |
308 | # define tidx2usize(idx) (((size_t) idx) * MALLOC_ALIGNMENT + MINSIZE - SIZE_SZ) | |
309 | ||
310 | /* When "x" is from chunksize(). */ | |
311 | # define csize2tidx(x) (((x) - MINSIZE + MALLOC_ALIGNMENT - 1) / MALLOC_ALIGNMENT) | |
312 | /* When "x" is a user-provided size. */ | |
313 | # define usize2tidx(x) csize2tidx (request2size (x)) | |
314 | ||
315 | /* With rounding and alignment, the bins are... | |
316 | idx 0 bytes 0..24 (64-bit) or 0..12 (32-bit) | |
317 | idx 1 bytes 25..40 or 13..20 | |
318 | idx 2 bytes 41..56 or 21..28 | |
319 | etc. */ | |
320 | ||
321 | /* This is another arbitrary limit, which tunables can change. Each | |
322 | tcache bin will hold at most this number of chunks. */ | |
323 | # define TCACHE_FILL_COUNT 7 | |
0ad788fa WD |
324 | |
325 | /* Maximum chunks in tcache bins for tunables. This value must fit the range | |
326 | of tcache->counts[] entries, else they may overflow. */ | |
327 | # define MAX_TCACHE_COUNT UINT16_MAX | |
d5c3fafc DD |
328 | #endif |
329 | ||
f65fd747 | 330 | |
fa8d436c UD |
331 | /* |
332 | REALLOC_ZERO_BYTES_FREES should be set if a call to | |
333 | realloc with zero bytes should be the same as a call to free. | |
334 | This is required by the C standard. Otherwise, since this malloc | |
335 | returns a unique pointer for malloc(0), so does realloc(p, 0). | |
336 | */ | |
337 | ||
338 | #ifndef REALLOC_ZERO_BYTES_FREES | |
339 | #define REALLOC_ZERO_BYTES_FREES 1 | |
340 | #endif | |
341 | ||
342 | /* | |
343 | TRIM_FASTBINS controls whether free() of a very small chunk can | |
344 | immediately lead to trimming. Setting to true (1) can reduce memory | |
345 | footprint, but will almost always slow down programs that use a lot | |
346 | of small chunks. | |
347 | ||
348 | Define this only if you are willing to give up some speed to more | |
349 | aggressively reduce system-level memory footprint when releasing | |
350 | memory in programs that use many small chunks. You can get | |
351 | essentially the same effect by setting MXFAST to 0, but this can | |
352 | lead to even greater slowdowns in programs using many small chunks. | |
353 | TRIM_FASTBINS is an in-between compile-time option, that disables | |
354 | only those chunks bordering topmost memory from being placed in | |
355 | fastbins. | |
356 | */ | |
357 | ||
358 | #ifndef TRIM_FASTBINS | |
359 | #define TRIM_FASTBINS 0 | |
360 | #endif | |
361 | ||
362 | ||
3b49edc0 | 363 | /* Definition for getting more memory from the OS. */ |
fa8d436c UD |
364 | #define MORECORE (*__morecore) |
365 | #define MORECORE_FAILURE 0 | |
22a89187 UD |
366 | void * __default_morecore (ptrdiff_t); |
367 | void *(*__morecore)(ptrdiff_t) = __default_morecore; | |
f65fd747 | 368 | |
f65fd747 | 369 | |
22a89187 | 370 | #include <string.h> |
f65fd747 | 371 | |
fa8d436c UD |
372 | /* |
373 | MORECORE-related declarations. By default, rely on sbrk | |
374 | */ | |
09f5e163 | 375 | |
f65fd747 | 376 | |
fa8d436c UD |
377 | /* |
378 | MORECORE is the name of the routine to call to obtain more memory | |
379 | from the system. See below for general guidance on writing | |
380 | alternative MORECORE functions, as well as a version for WIN32 and a | |
381 | sample version for pre-OSX macos. | |
382 | */ | |
f65fd747 | 383 | |
fa8d436c UD |
384 | #ifndef MORECORE |
385 | #define MORECORE sbrk | |
386 | #endif | |
f65fd747 | 387 | |
fa8d436c UD |
388 | /* |
389 | MORECORE_FAILURE is the value returned upon failure of MORECORE | |
390 | as well as mmap. Since it cannot be an otherwise valid memory address, | |
391 | and must reflect values of standard sys calls, you probably ought not | |
392 | try to redefine it. | |
393 | */ | |
09f5e163 | 394 | |
fa8d436c UD |
395 | #ifndef MORECORE_FAILURE |
396 | #define MORECORE_FAILURE (-1) | |
397 | #endif | |
398 | ||
399 | /* | |
400 | If MORECORE_CONTIGUOUS is true, take advantage of fact that | |
401 | consecutive calls to MORECORE with positive arguments always return | |
402 | contiguous increasing addresses. This is true of unix sbrk. Even | |
403 | if not defined, when regions happen to be contiguous, malloc will | |
404 | permit allocations spanning regions obtained from different | |
405 | calls. But defining this when applicable enables some stronger | |
406 | consistency checks and space efficiencies. | |
407 | */ | |
f65fd747 | 408 | |
fa8d436c UD |
409 | #ifndef MORECORE_CONTIGUOUS |
410 | #define MORECORE_CONTIGUOUS 1 | |
f65fd747 UD |
411 | #endif |
412 | ||
fa8d436c UD |
413 | /* |
414 | Define MORECORE_CANNOT_TRIM if your version of MORECORE | |
415 | cannot release space back to the system when given negative | |
416 | arguments. This is generally necessary only if you are using | |
417 | a hand-crafted MORECORE function that cannot handle negative arguments. | |
418 | */ | |
419 | ||
420 | /* #define MORECORE_CANNOT_TRIM */ | |
f65fd747 | 421 | |
fa8d436c UD |
422 | /* MORECORE_CLEARS (default 1) |
423 | The degree to which the routine mapped to MORECORE zeroes out | |
424 | memory: never (0), only for newly allocated space (1) or always | |
425 | (2). The distinction between (1) and (2) is necessary because on | |
426 | some systems, if the application first decrements and then | |
427 | increments the break value, the contents of the reallocated space | |
428 | are unspecified. | |
6c8dbf00 | 429 | */ |
fa8d436c UD |
430 | |
431 | #ifndef MORECORE_CLEARS | |
6c8dbf00 | 432 | # define MORECORE_CLEARS 1 |
7cabd57c UD |
433 | #endif |
434 | ||
fa8d436c | 435 | |
a9177ff5 | 436 | /* |
fa8d436c | 437 | MMAP_AS_MORECORE_SIZE is the minimum mmap size argument to use if |
22a89187 UD |
438 | sbrk fails, and mmap is used as a backup. The value must be a |
439 | multiple of page size. This backup strategy generally applies only | |
440 | when systems have "holes" in address space, so sbrk cannot perform | |
441 | contiguous expansion, but there is still space available on system. | |
442 | On systems for which this is known to be useful (i.e. most linux | |
443 | kernels), this occurs only when programs allocate huge amounts of | |
444 | memory. Between this, and the fact that mmap regions tend to be | |
445 | limited, the size should be large, to avoid too many mmap calls and | |
446 | thus avoid running out of kernel resources. */ | |
fa8d436c UD |
447 | |
448 | #ifndef MMAP_AS_MORECORE_SIZE | |
449 | #define MMAP_AS_MORECORE_SIZE (1024 * 1024) | |
f65fd747 UD |
450 | #endif |
451 | ||
452 | /* | |
453 | Define HAVE_MREMAP to make realloc() use mremap() to re-allocate | |
2a26ef3a | 454 | large blocks. |
f65fd747 UD |
455 | */ |
456 | ||
457 | #ifndef HAVE_MREMAP | |
fa8d436c | 458 | #define HAVE_MREMAP 0 |
f65fd747 UD |
459 | #endif |
460 | ||
2ba3cfa1 FW |
461 | /* We may need to support __malloc_initialize_hook for backwards |
462 | compatibility. */ | |
463 | ||
464 | #if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_24) | |
465 | # define HAVE_MALLOC_INIT_HOOK 1 | |
466 | #else | |
467 | # define HAVE_MALLOC_INIT_HOOK 0 | |
468 | #endif | |
469 | ||
f65fd747 | 470 | |
f65fd747 | 471 | /* |
f65fd747 | 472 | This version of malloc supports the standard SVID/XPG mallinfo |
fa8d436c UD |
473 | routine that returns a struct containing usage properties and |
474 | statistics. It should work on any SVID/XPG compliant system that has | |
475 | a /usr/include/malloc.h defining struct mallinfo. (If you'd like to | |
476 | install such a thing yourself, cut out the preliminary declarations | |
477 | as described above and below and save them in a malloc.h file. But | |
478 | there's no compelling reason to bother to do this.) | |
f65fd747 UD |
479 | |
480 | The main declaration needed is the mallinfo struct that is returned | |
481 | (by-copy) by mallinfo(). The SVID/XPG malloinfo struct contains a | |
fa8d436c UD |
482 | bunch of fields that are not even meaningful in this version of |
483 | malloc. These fields are are instead filled by mallinfo() with | |
484 | other numbers that might be of interest. | |
f65fd747 UD |
485 | */ |
486 | ||
f65fd747 | 487 | |
fa8d436c | 488 | /* ---------- description of public routines ------------ */ |
f65fd747 UD |
489 | |
490 | /* | |
fa8d436c UD |
491 | malloc(size_t n) |
492 | Returns a pointer to a newly allocated chunk of at least n bytes, or null | |
493 | if no space is available. Additionally, on failure, errno is | |
494 | set to ENOMEM on ANSI C systems. | |
495 | ||
496 | If n is zero, malloc returns a minumum-sized chunk. (The minimum | |
497 | size is 16 bytes on most 32bit systems, and 24 or 32 bytes on 64bit | |
498 | systems.) On most systems, size_t is an unsigned type, so calls | |
499 | with negative arguments are interpreted as requests for huge amounts | |
500 | of space, which will often fail. The maximum supported value of n | |
501 | differs across systems, but is in all cases less than the maximum | |
502 | representable value of a size_t. | |
f65fd747 | 503 | */ |
3b49edc0 UD |
504 | void* __libc_malloc(size_t); |
505 | libc_hidden_proto (__libc_malloc) | |
f65fd747 | 506 | |
fa8d436c | 507 | /* |
22a89187 | 508 | free(void* p) |
fa8d436c UD |
509 | Releases the chunk of memory pointed to by p, that had been previously |
510 | allocated using malloc or a related routine such as realloc. | |
511 | It has no effect if p is null. It can have arbitrary (i.e., bad!) | |
512 | effects if p has already been freed. | |
513 | ||
514 | Unless disabled (using mallopt), freeing very large spaces will | |
515 | when possible, automatically trigger operations that give | |
516 | back unused memory to the system, thus reducing program footprint. | |
517 | */ | |
3b49edc0 UD |
518 | void __libc_free(void*); |
519 | libc_hidden_proto (__libc_free) | |
f65fd747 | 520 | |
fa8d436c UD |
521 | /* |
522 | calloc(size_t n_elements, size_t element_size); | |
523 | Returns a pointer to n_elements * element_size bytes, with all locations | |
524 | set to zero. | |
525 | */ | |
3b49edc0 | 526 | void* __libc_calloc(size_t, size_t); |
f65fd747 UD |
527 | |
528 | /* | |
22a89187 | 529 | realloc(void* p, size_t n) |
fa8d436c UD |
530 | Returns a pointer to a chunk of size n that contains the same data |
531 | as does chunk p up to the minimum of (n, p's size) bytes, or null | |
a9177ff5 | 532 | if no space is available. |
f65fd747 | 533 | |
fa8d436c UD |
534 | The returned pointer may or may not be the same as p. The algorithm |
535 | prefers extending p when possible, otherwise it employs the | |
536 | equivalent of a malloc-copy-free sequence. | |
f65fd747 | 537 | |
a9177ff5 | 538 | If p is null, realloc is equivalent to malloc. |
f65fd747 | 539 | |
fa8d436c UD |
540 | If space is not available, realloc returns null, errno is set (if on |
541 | ANSI) and p is NOT freed. | |
f65fd747 | 542 | |
fa8d436c UD |
543 | if n is for fewer bytes than already held by p, the newly unused |
544 | space is lopped off and freed if possible. Unless the #define | |
545 | REALLOC_ZERO_BYTES_FREES is set, realloc with a size argument of | |
546 | zero (re)allocates a minimum-sized chunk. | |
f65fd747 | 547 | |
3b5f801d DD |
548 | Large chunks that were internally obtained via mmap will always be |
549 | grown using malloc-copy-free sequences unless the system supports | |
550 | MREMAP (currently only linux). | |
f65fd747 | 551 | |
fa8d436c UD |
552 | The old unix realloc convention of allowing the last-free'd chunk |
553 | to be used as an argument to realloc is not supported. | |
f65fd747 | 554 | */ |
3b49edc0 UD |
555 | void* __libc_realloc(void*, size_t); |
556 | libc_hidden_proto (__libc_realloc) | |
f65fd747 | 557 | |
fa8d436c UD |
558 | /* |
559 | memalign(size_t alignment, size_t n); | |
560 | Returns a pointer to a newly allocated chunk of n bytes, aligned | |
561 | in accord with the alignment argument. | |
562 | ||
563 | The alignment argument should be a power of two. If the argument is | |
564 | not a power of two, the nearest greater power is used. | |
565 | 8-byte alignment is guaranteed by normal malloc calls, so don't | |
566 | bother calling memalign with an argument of 8 or less. | |
567 | ||
568 | Overreliance on memalign is a sure way to fragment space. | |
569 | */ | |
3b49edc0 UD |
570 | void* __libc_memalign(size_t, size_t); |
571 | libc_hidden_proto (__libc_memalign) | |
f65fd747 UD |
572 | |
573 | /* | |
fa8d436c UD |
574 | valloc(size_t n); |
575 | Equivalent to memalign(pagesize, n), where pagesize is the page | |
576 | size of the system. If the pagesize is unknown, 4096 is used. | |
577 | */ | |
3b49edc0 | 578 | void* __libc_valloc(size_t); |
fa8d436c | 579 | |
f65fd747 | 580 | |
f65fd747 | 581 | |
fa8d436c UD |
582 | /* |
583 | mallopt(int parameter_number, int parameter_value) | |
584 | Sets tunable parameters The format is to provide a | |
585 | (parameter-number, parameter-value) pair. mallopt then sets the | |
586 | corresponding parameter to the argument value if it can (i.e., so | |
587 | long as the value is meaningful), and returns 1 if successful else | |
588 | 0. SVID/XPG/ANSI defines four standard param numbers for mallopt, | |
589 | normally defined in malloc.h. Only one of these (M_MXFAST) is used | |
590 | in this malloc. The others (M_NLBLKS, M_GRAIN, M_KEEP) don't apply, | |
591 | so setting them has no effect. But this malloc also supports four | |
592 | other options in mallopt. See below for details. Briefly, supported | |
593 | parameters are as follows (listed defaults are for "typical" | |
594 | configurations). | |
595 | ||
596 | Symbol param # default allowed param values | |
597 | M_MXFAST 1 64 0-80 (0 disables fastbins) | |
598 | M_TRIM_THRESHOLD -1 128*1024 any (-1U disables trimming) | |
a9177ff5 | 599 | M_TOP_PAD -2 0 any |
fa8d436c UD |
600 | M_MMAP_THRESHOLD -3 128*1024 any (or 0 if no MMAP support) |
601 | M_MMAP_MAX -4 65536 any (0 disables use of mmap) | |
602 | */ | |
3b49edc0 UD |
603 | int __libc_mallopt(int, int); |
604 | libc_hidden_proto (__libc_mallopt) | |
fa8d436c UD |
605 | |
606 | ||
607 | /* | |
608 | mallinfo() | |
609 | Returns (by copy) a struct containing various summary statistics: | |
610 | ||
a9177ff5 RM |
611 | arena: current total non-mmapped bytes allocated from system |
612 | ordblks: the number of free chunks | |
fa8d436c | 613 | smblks: the number of fastbin blocks (i.e., small chunks that |
72f90263 | 614 | have been freed but not use resused or consolidated) |
a9177ff5 RM |
615 | hblks: current number of mmapped regions |
616 | hblkhd: total bytes held in mmapped regions | |
ca135f82 | 617 | usmblks: always 0 |
a9177ff5 | 618 | fsmblks: total bytes held in fastbin blocks |
fa8d436c | 619 | uordblks: current total allocated space (normal or mmapped) |
a9177ff5 | 620 | fordblks: total free space |
fa8d436c | 621 | keepcost: the maximum number of bytes that could ideally be released |
72f90263 UD |
622 | back to system via malloc_trim. ("ideally" means that |
623 | it ignores page restrictions etc.) | |
fa8d436c UD |
624 | |
625 | Because these fields are ints, but internal bookkeeping may | |
a9177ff5 | 626 | be kept as longs, the reported values may wrap around zero and |
fa8d436c UD |
627 | thus be inaccurate. |
628 | */ | |
3b49edc0 | 629 | struct mallinfo __libc_mallinfo(void); |
88764ae2 | 630 | |
f65fd747 | 631 | |
fa8d436c UD |
632 | /* |
633 | pvalloc(size_t n); | |
634 | Equivalent to valloc(minimum-page-that-holds(n)), that is, | |
635 | round up n to nearest pagesize. | |
636 | */ | |
3b49edc0 | 637 | void* __libc_pvalloc(size_t); |
fa8d436c UD |
638 | |
639 | /* | |
640 | malloc_trim(size_t pad); | |
641 | ||
642 | If possible, gives memory back to the system (via negative | |
643 | arguments to sbrk) if there is unused memory at the `high' end of | |
644 | the malloc pool. You can call this after freeing large blocks of | |
645 | memory to potentially reduce the system-level memory requirements | |
646 | of a program. However, it cannot guarantee to reduce memory. Under | |
647 | some allocation patterns, some large free blocks of memory will be | |
648 | locked between two used chunks, so they cannot be given back to | |
649 | the system. | |
a9177ff5 | 650 | |
fa8d436c UD |
651 | The `pad' argument to malloc_trim represents the amount of free |
652 | trailing space to leave untrimmed. If this argument is zero, | |
653 | only the minimum amount of memory to maintain internal data | |
654 | structures will be left (one page or less). Non-zero arguments | |
655 | can be supplied to maintain enough trailing space to service | |
656 | future expected allocations without having to re-obtain memory | |
657 | from the system. | |
a9177ff5 | 658 | |
fa8d436c UD |
659 | Malloc_trim returns 1 if it actually released any memory, else 0. |
660 | On systems that do not support "negative sbrks", it will always | |
c958a6a4 | 661 | return 0. |
fa8d436c | 662 | */ |
3b49edc0 | 663 | int __malloc_trim(size_t); |
fa8d436c UD |
664 | |
665 | /* | |
22a89187 | 666 | malloc_usable_size(void* p); |
fa8d436c UD |
667 | |
668 | Returns the number of bytes you can actually use in | |
669 | an allocated chunk, which may be more than you requested (although | |
670 | often not) due to alignment and minimum size constraints. | |
671 | You can use this many bytes without worrying about | |
672 | overwriting other allocated objects. This is not a particularly great | |
673 | programming practice. malloc_usable_size can be more useful in | |
674 | debugging and assertions, for example: | |
675 | ||
676 | p = malloc(n); | |
677 | assert(malloc_usable_size(p) >= 256); | |
678 | ||
679 | */ | |
3b49edc0 | 680 | size_t __malloc_usable_size(void*); |
fa8d436c UD |
681 | |
682 | /* | |
683 | malloc_stats(); | |
684 | Prints on stderr the amount of space obtained from the system (both | |
685 | via sbrk and mmap), the maximum amount (which may be more than | |
686 | current if malloc_trim and/or munmap got called), and the current | |
687 | number of bytes allocated via malloc (or realloc, etc) but not yet | |
688 | freed. Note that this is the number of bytes allocated, not the | |
689 | number requested. It will be larger than the number requested | |
690 | because of alignment and bookkeeping overhead. Because it includes | |
691 | alignment wastage as being in use, this figure may be greater than | |
692 | zero even when no user-level chunks are allocated. | |
693 | ||
694 | The reported current and maximum system memory can be inaccurate if | |
695 | a program makes other calls to system memory allocation functions | |
696 | (normally sbrk) outside of malloc. | |
697 | ||
698 | malloc_stats prints only the most commonly interesting statistics. | |
699 | More information can be obtained by calling mallinfo. | |
700 | ||
701 | */ | |
3b49edc0 | 702 | void __malloc_stats(void); |
f65fd747 | 703 | |
f7ddf3d3 UD |
704 | /* |
705 | posix_memalign(void **memptr, size_t alignment, size_t size); | |
706 | ||
707 | POSIX wrapper like memalign(), checking for validity of size. | |
708 | */ | |
709 | int __posix_memalign(void **, size_t, size_t); | |
f7ddf3d3 | 710 | |
fa8d436c UD |
711 | /* mallopt tuning options */ |
712 | ||
f65fd747 | 713 | /* |
fa8d436c UD |
714 | M_MXFAST is the maximum request size used for "fastbins", special bins |
715 | that hold returned chunks without consolidating their spaces. This | |
716 | enables future requests for chunks of the same size to be handled | |
717 | very quickly, but can increase fragmentation, and thus increase the | |
718 | overall memory footprint of a program. | |
719 | ||
720 | This malloc manages fastbins very conservatively yet still | |
721 | efficiently, so fragmentation is rarely a problem for values less | |
722 | than or equal to the default. The maximum supported value of MXFAST | |
723 | is 80. You wouldn't want it any higher than this anyway. Fastbins | |
724 | are designed especially for use with many small structs, objects or | |
725 | strings -- the default handles structs/objects/arrays with sizes up | |
726 | to 8 4byte fields, or small strings representing words, tokens, | |
727 | etc. Using fastbins for larger objects normally worsens | |
728 | fragmentation without improving speed. | |
729 | ||
730 | M_MXFAST is set in REQUEST size units. It is internally used in | |
731 | chunksize units, which adds padding and alignment. You can reduce | |
732 | M_MXFAST to 0 to disable all use of fastbins. This causes the malloc | |
733 | algorithm to be a closer approximation of fifo-best-fit in all cases, | |
734 | not just for larger requests, but will generally cause it to be | |
735 | slower. | |
f65fd747 UD |
736 | */ |
737 | ||
738 | ||
fa8d436c UD |
739 | /* M_MXFAST is a standard SVID/XPG tuning option, usually listed in malloc.h */ |
740 | #ifndef M_MXFAST | |
a9177ff5 | 741 | #define M_MXFAST 1 |
fa8d436c | 742 | #endif |
f65fd747 | 743 | |
fa8d436c | 744 | #ifndef DEFAULT_MXFAST |
425ce2ed | 745 | #define DEFAULT_MXFAST (64 * SIZE_SZ / 4) |
10dc2a90 UD |
746 | #endif |
747 | ||
10dc2a90 | 748 | |
fa8d436c UD |
749 | /* |
750 | M_TRIM_THRESHOLD is the maximum amount of unused top-most memory | |
751 | to keep before releasing via malloc_trim in free(). | |
752 | ||
753 | Automatic trimming is mainly useful in long-lived programs. | |
754 | Because trimming via sbrk can be slow on some systems, and can | |
755 | sometimes be wasteful (in cases where programs immediately | |
756 | afterward allocate more large chunks) the value should be high | |
757 | enough so that your overall system performance would improve by | |
758 | releasing this much memory. | |
759 | ||
760 | The trim threshold and the mmap control parameters (see below) | |
761 | can be traded off with one another. Trimming and mmapping are | |
762 | two different ways of releasing unused memory back to the | |
763 | system. Between these two, it is often possible to keep | |
764 | system-level demands of a long-lived program down to a bare | |
765 | minimum. For example, in one test suite of sessions measuring | |
766 | the XF86 X server on Linux, using a trim threshold of 128K and a | |
767 | mmap threshold of 192K led to near-minimal long term resource | |
768 | consumption. | |
769 | ||
770 | If you are using this malloc in a long-lived program, it should | |
771 | pay to experiment with these values. As a rough guide, you | |
772 | might set to a value close to the average size of a process | |
773 | (program) running on your system. Releasing this much memory | |
774 | would allow such a process to run in memory. Generally, it's | |
775 | worth it to tune for trimming rather tham memory mapping when a | |
776 | program undergoes phases where several large chunks are | |
777 | allocated and released in ways that can reuse each other's | |
778 | storage, perhaps mixed with phases where there are no such | |
779 | chunks at all. And in well-behaved long-lived programs, | |
780 | controlling release of large blocks via trimming versus mapping | |
781 | is usually faster. | |
782 | ||
783 | However, in most programs, these parameters serve mainly as | |
784 | protection against the system-level effects of carrying around | |
785 | massive amounts of unneeded memory. Since frequent calls to | |
786 | sbrk, mmap, and munmap otherwise degrade performance, the default | |
787 | parameters are set to relatively high values that serve only as | |
788 | safeguards. | |
789 | ||
790 | The trim value It must be greater than page size to have any useful | |
a9177ff5 | 791 | effect. To disable trimming completely, you can set to |
fa8d436c UD |
792 | (unsigned long)(-1) |
793 | ||
794 | Trim settings interact with fastbin (MXFAST) settings: Unless | |
795 | TRIM_FASTBINS is defined, automatic trimming never takes place upon | |
796 | freeing a chunk with size less than or equal to MXFAST. Trimming is | |
797 | instead delayed until subsequent freeing of larger chunks. However, | |
798 | you can still force an attempted trim by calling malloc_trim. | |
799 | ||
800 | Also, trimming is not generally possible in cases where | |
801 | the main arena is obtained via mmap. | |
802 | ||
803 | Note that the trick some people use of mallocing a huge space and | |
804 | then freeing it at program startup, in an attempt to reserve system | |
805 | memory, doesn't have the intended effect under automatic trimming, | |
806 | since that memory will immediately be returned to the system. | |
807 | */ | |
808 | ||
809 | #define M_TRIM_THRESHOLD -1 | |
810 | ||
811 | #ifndef DEFAULT_TRIM_THRESHOLD | |
812 | #define DEFAULT_TRIM_THRESHOLD (128 * 1024) | |
813 | #endif | |
814 | ||
815 | /* | |
816 | M_TOP_PAD is the amount of extra `padding' space to allocate or | |
817 | retain whenever sbrk is called. It is used in two ways internally: | |
818 | ||
819 | * When sbrk is called to extend the top of the arena to satisfy | |
820 | a new malloc request, this much padding is added to the sbrk | |
821 | request. | |
822 | ||
823 | * When malloc_trim is called automatically from free(), | |
824 | it is used as the `pad' argument. | |
825 | ||
826 | In both cases, the actual amount of padding is rounded | |
827 | so that the end of the arena is always a system page boundary. | |
828 | ||
829 | The main reason for using padding is to avoid calling sbrk so | |
830 | often. Having even a small pad greatly reduces the likelihood | |
831 | that nearly every malloc request during program start-up (or | |
832 | after trimming) will invoke sbrk, which needlessly wastes | |
833 | time. | |
834 | ||
835 | Automatic rounding-up to page-size units is normally sufficient | |
836 | to avoid measurable overhead, so the default is 0. However, in | |
837 | systems where sbrk is relatively slow, it can pay to increase | |
838 | this value, at the expense of carrying around more memory than | |
839 | the program needs. | |
840 | */ | |
10dc2a90 | 841 | |
fa8d436c | 842 | #define M_TOP_PAD -2 |
10dc2a90 | 843 | |
fa8d436c UD |
844 | #ifndef DEFAULT_TOP_PAD |
845 | #define DEFAULT_TOP_PAD (0) | |
846 | #endif | |
f65fd747 | 847 | |
1d05c2fb UD |
848 | /* |
849 | MMAP_THRESHOLD_MAX and _MIN are the bounds on the dynamically | |
850 | adjusted MMAP_THRESHOLD. | |
851 | */ | |
852 | ||
853 | #ifndef DEFAULT_MMAP_THRESHOLD_MIN | |
854 | #define DEFAULT_MMAP_THRESHOLD_MIN (128 * 1024) | |
855 | #endif | |
856 | ||
857 | #ifndef DEFAULT_MMAP_THRESHOLD_MAX | |
e404fb16 UD |
858 | /* For 32-bit platforms we cannot increase the maximum mmap |
859 | threshold much because it is also the minimum value for the | |
bd2c2341 UD |
860 | maximum heap size and its alignment. Going above 512k (i.e., 1M |
861 | for new heaps) wastes too much address space. */ | |
e404fb16 | 862 | # if __WORDSIZE == 32 |
bd2c2341 | 863 | # define DEFAULT_MMAP_THRESHOLD_MAX (512 * 1024) |
e404fb16 | 864 | # else |
bd2c2341 | 865 | # define DEFAULT_MMAP_THRESHOLD_MAX (4 * 1024 * 1024 * sizeof(long)) |
e404fb16 | 866 | # endif |
1d05c2fb UD |
867 | #endif |
868 | ||
fa8d436c UD |
869 | /* |
870 | M_MMAP_THRESHOLD is the request size threshold for using mmap() | |
871 | to service a request. Requests of at least this size that cannot | |
872 | be allocated using already-existing space will be serviced via mmap. | |
873 | (If enough normal freed space already exists it is used instead.) | |
874 | ||
875 | Using mmap segregates relatively large chunks of memory so that | |
876 | they can be individually obtained and released from the host | |
877 | system. A request serviced through mmap is never reused by any | |
878 | other request (at least not directly; the system may just so | |
879 | happen to remap successive requests to the same locations). | |
880 | ||
881 | Segregating space in this way has the benefits that: | |
882 | ||
a9177ff5 RM |
883 | 1. Mmapped space can ALWAYS be individually released back |
884 | to the system, which helps keep the system level memory | |
885 | demands of a long-lived program low. | |
fa8d436c UD |
886 | 2. Mapped memory can never become `locked' between |
887 | other chunks, as can happen with normally allocated chunks, which | |
888 | means that even trimming via malloc_trim would not release them. | |
889 | 3. On some systems with "holes" in address spaces, mmap can obtain | |
890 | memory that sbrk cannot. | |
891 | ||
892 | However, it has the disadvantages that: | |
893 | ||
894 | 1. The space cannot be reclaimed, consolidated, and then | |
895 | used to service later requests, as happens with normal chunks. | |
896 | 2. It can lead to more wastage because of mmap page alignment | |
897 | requirements | |
898 | 3. It causes malloc performance to be more dependent on host | |
899 | system memory management support routines which may vary in | |
900 | implementation quality and may impose arbitrary | |
901 | limitations. Generally, servicing a request via normal | |
902 | malloc steps is faster than going through a system's mmap. | |
903 | ||
904 | The advantages of mmap nearly always outweigh disadvantages for | |
905 | "large" chunks, but the value of "large" varies across systems. The | |
906 | default is an empirically derived value that works well in most | |
907 | systems. | |
1d05c2fb UD |
908 | |
909 | ||
910 | Update in 2006: | |
911 | The above was written in 2001. Since then the world has changed a lot. | |
912 | Memory got bigger. Applications got bigger. The virtual address space | |
913 | layout in 32 bit linux changed. | |
914 | ||
915 | In the new situation, brk() and mmap space is shared and there are no | |
916 | artificial limits on brk size imposed by the kernel. What is more, | |
917 | applications have started using transient allocations larger than the | |
918 | 128Kb as was imagined in 2001. | |
919 | ||
920 | The price for mmap is also high now; each time glibc mmaps from the | |
921 | kernel, the kernel is forced to zero out the memory it gives to the | |
922 | application. Zeroing memory is expensive and eats a lot of cache and | |
923 | memory bandwidth. This has nothing to do with the efficiency of the | |
924 | virtual memory system, by doing mmap the kernel just has no choice but | |
925 | to zero. | |
926 | ||
927 | In 2001, the kernel had a maximum size for brk() which was about 800 | |
928 | megabytes on 32 bit x86, at that point brk() would hit the first | |
929 | mmaped shared libaries and couldn't expand anymore. With current 2.6 | |
930 | kernels, the VA space layout is different and brk() and mmap | |
931 | both can span the entire heap at will. | |
932 | ||
933 | Rather than using a static threshold for the brk/mmap tradeoff, | |
934 | we are now using a simple dynamic one. The goal is still to avoid | |
935 | fragmentation. The old goals we kept are | |
936 | 1) try to get the long lived large allocations to use mmap() | |
937 | 2) really large allocations should always use mmap() | |
938 | and we're adding now: | |
939 | 3) transient allocations should use brk() to avoid forcing the kernel | |
940 | having to zero memory over and over again | |
941 | ||
942 | The implementation works with a sliding threshold, which is by default | |
943 | limited to go between 128Kb and 32Mb (64Mb for 64 bitmachines) and starts | |
944 | out at 128Kb as per the 2001 default. | |
945 | ||
946 | This allows us to satisfy requirement 1) under the assumption that long | |
947 | lived allocations are made early in the process' lifespan, before it has | |
948 | started doing dynamic allocations of the same size (which will | |
949 | increase the threshold). | |
950 | ||
951 | The upperbound on the threshold satisfies requirement 2) | |
952 | ||
953 | The threshold goes up in value when the application frees memory that was | |
954 | allocated with the mmap allocator. The idea is that once the application | |
955 | starts freeing memory of a certain size, it's highly probable that this is | |
956 | a size the application uses for transient allocations. This estimator | |
957 | is there to satisfy the new third requirement. | |
958 | ||
f65fd747 UD |
959 | */ |
960 | ||
fa8d436c | 961 | #define M_MMAP_THRESHOLD -3 |
f65fd747 | 962 | |
fa8d436c | 963 | #ifndef DEFAULT_MMAP_THRESHOLD |
1d05c2fb | 964 | #define DEFAULT_MMAP_THRESHOLD DEFAULT_MMAP_THRESHOLD_MIN |
fa8d436c UD |
965 | #endif |
966 | ||
967 | /* | |
968 | M_MMAP_MAX is the maximum number of requests to simultaneously | |
969 | service using mmap. This parameter exists because | |
970 | some systems have a limited number of internal tables for | |
971 | use by mmap, and using more than a few of them may degrade | |
972 | performance. | |
973 | ||
974 | The default is set to a value that serves only as a safeguard. | |
22a89187 | 975 | Setting to 0 disables use of mmap for servicing large requests. |
fa8d436c | 976 | */ |
f65fd747 | 977 | |
fa8d436c UD |
978 | #define M_MMAP_MAX -4 |
979 | ||
980 | #ifndef DEFAULT_MMAP_MAX | |
fa8d436c | 981 | #define DEFAULT_MMAP_MAX (65536) |
f65fd747 UD |
982 | #endif |
983 | ||
100351c3 | 984 | #include <malloc.h> |
f65fd747 | 985 | |
fa8d436c UD |
986 | #ifndef RETURN_ADDRESS |
987 | #define RETURN_ADDRESS(X_) (NULL) | |
9ae6fc54 | 988 | #endif |
431c33c0 | 989 | |
fa8d436c UD |
990 | /* Forward declarations. */ |
991 | struct malloc_chunk; | |
992 | typedef struct malloc_chunk* mchunkptr; | |
431c33c0 | 993 | |
fa8d436c | 994 | /* Internal routines. */ |
f65fd747 | 995 | |
22a89187 | 996 | static void* _int_malloc(mstate, size_t); |
425ce2ed | 997 | static void _int_free(mstate, mchunkptr, int); |
22a89187 | 998 | static void* _int_realloc(mstate, mchunkptr, INTERNAL_SIZE_T, |
6e4b2107 | 999 | INTERNAL_SIZE_T); |
22a89187 | 1000 | static void* _int_memalign(mstate, size_t, size_t); |
10ad46bc OB |
1001 | static void* _mid_memalign(size_t, size_t, void *); |
1002 | ||
ac3ed168 | 1003 | static void malloc_printerr(const char *str) __attribute__ ((noreturn)); |
fa8d436c | 1004 | |
0c71122c FW |
1005 | static void* mem2mem_check(void *p, size_t sz); |
1006 | static void top_check(void); | |
1007 | static void munmap_chunk(mchunkptr p); | |
a9177ff5 | 1008 | #if HAVE_MREMAP |
0c71122c | 1009 | static mchunkptr mremap_chunk(mchunkptr p, size_t new_size); |
a9177ff5 | 1010 | #endif |
fa8d436c | 1011 | |
22a89187 UD |
1012 | static void* malloc_check(size_t sz, const void *caller); |
1013 | static void free_check(void* mem, const void *caller); | |
1014 | static void* realloc_check(void* oldmem, size_t bytes, | |
1015 | const void *caller); | |
1016 | static void* memalign_check(size_t alignment, size_t bytes, | |
1017 | const void *caller); | |
f65fd747 | 1018 | |
fa8d436c | 1019 | /* ------------------ MMAP support ------------------ */ |
f65fd747 | 1020 | |
f65fd747 | 1021 | |
fa8d436c | 1022 | #include <fcntl.h> |
fa8d436c | 1023 | #include <sys/mman.h> |
f65fd747 | 1024 | |
fa8d436c UD |
1025 | #if !defined(MAP_ANONYMOUS) && defined(MAP_ANON) |
1026 | # define MAP_ANONYMOUS MAP_ANON | |
1027 | #endif | |
f65fd747 | 1028 | |
fa8d436c | 1029 | #ifndef MAP_NORESERVE |
3b49edc0 | 1030 | # define MAP_NORESERVE 0 |
f65fd747 UD |
1031 | #endif |
1032 | ||
fa8d436c | 1033 | #define MMAP(addr, size, prot, flags) \ |
3b49edc0 | 1034 | __mmap((addr), (size), (prot), (flags)|MAP_ANONYMOUS|MAP_PRIVATE, -1, 0) |
f65fd747 | 1035 | |
f65fd747 UD |
1036 | |
1037 | /* | |
fa8d436c | 1038 | ----------------------- Chunk representations ----------------------- |
f65fd747 UD |
1039 | */ |
1040 | ||
1041 | ||
fa8d436c UD |
1042 | /* |
1043 | This struct declaration is misleading (but accurate and necessary). | |
1044 | It declares a "view" into memory allowing access to necessary | |
1045 | fields at known offsets from a given base. See explanation below. | |
1046 | */ | |
1047 | ||
1048 | struct malloc_chunk { | |
1049 | ||
e9c4fe93 FW |
1050 | INTERNAL_SIZE_T mchunk_prev_size; /* Size of previous chunk (if free). */ |
1051 | INTERNAL_SIZE_T mchunk_size; /* Size in bytes, including overhead. */ | |
fa8d436c UD |
1052 | |
1053 | struct malloc_chunk* fd; /* double links -- used only if free. */ | |
f65fd747 | 1054 | struct malloc_chunk* bk; |
7ecfbd38 UD |
1055 | |
1056 | /* Only used for large blocks: pointer to next larger size. */ | |
1057 | struct malloc_chunk* fd_nextsize; /* double links -- used only if free. */ | |
1058 | struct malloc_chunk* bk_nextsize; | |
f65fd747 UD |
1059 | }; |
1060 | ||
f65fd747 UD |
1061 | |
1062 | /* | |
f65fd747 UD |
1063 | malloc_chunk details: |
1064 | ||
1065 | (The following includes lightly edited explanations by Colin Plumb.) | |
1066 | ||
1067 | Chunks of memory are maintained using a `boundary tag' method as | |
1068 | described in e.g., Knuth or Standish. (See the paper by Paul | |
1069 | Wilson ftp://ftp.cs.utexas.edu/pub/garbage/allocsrv.ps for a | |
1070 | survey of such techniques.) Sizes of free chunks are stored both | |
1071 | in the front of each chunk and at the end. This makes | |
1072 | consolidating fragmented chunks into bigger chunks very fast. The | |
1073 | size fields also hold bits representing whether chunks are free or | |
1074 | in use. | |
1075 | ||
1076 | An allocated chunk looks like this: | |
1077 | ||
1078 | ||
1079 | chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
ae9166f2 | 1080 | | Size of previous chunk, if unallocated (P clear) | |
72f90263 | 1081 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
ae9166f2 | 1082 | | Size of chunk, in bytes |A|M|P| |
f65fd747 | 1083 | mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
72f90263 UD |
1084 | | User data starts here... . |
1085 | . . | |
1086 | . (malloc_usable_size() bytes) . | |
1087 | . | | |
f65fd747 | 1088 | nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
ae9166f2 FW |
1089 | | (size of chunk, but used for application data) | |
1090 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
1091 | | Size of next chunk, in bytes |A|0|1| | |
72f90263 | 1092 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
f65fd747 UD |
1093 | |
1094 | Where "chunk" is the front of the chunk for the purpose of most of | |
1095 | the malloc code, but "mem" is the pointer that is returned to the | |
1096 | user. "Nextchunk" is the beginning of the next contiguous chunk. | |
1097 | ||
6f65e668 | 1098 | Chunks always begin on even word boundaries, so the mem portion |
f65fd747 | 1099 | (which is returned to the user) is also on an even word boundary, and |
fa8d436c | 1100 | thus at least double-word aligned. |
f65fd747 UD |
1101 | |
1102 | Free chunks are stored in circular doubly-linked lists, and look like this: | |
1103 | ||
1104 | chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
ae9166f2 | 1105 | | Size of previous chunk, if unallocated (P clear) | |
72f90263 | 1106 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
ae9166f2 | 1107 | `head:' | Size of chunk, in bytes |A|0|P| |
f65fd747 | 1108 | mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
72f90263 UD |
1109 | | Forward pointer to next chunk in list | |
1110 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
1111 | | Back pointer to previous chunk in list | | |
1112 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
1113 | | Unused space (may be 0 bytes long) . | |
1114 | . . | |
1115 | . | | |
f65fd747 UD |
1116 | nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
1117 | `foot:' | Size of chunk, in bytes | | |
72f90263 | 1118 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
ae9166f2 FW |
1119 | | Size of next chunk, in bytes |A|0|0| |
1120 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
f65fd747 UD |
1121 | |
1122 | The P (PREV_INUSE) bit, stored in the unused low-order bit of the | |
1123 | chunk size (which is always a multiple of two words), is an in-use | |
1124 | bit for the *previous* chunk. If that bit is *clear*, then the | |
1125 | word before the current chunk size contains the previous chunk | |
1126 | size, and can be used to find the front of the previous chunk. | |
fa8d436c UD |
1127 | The very first chunk allocated always has this bit set, |
1128 | preventing access to non-existent (or non-owned) memory. If | |
1129 | prev_inuse is set for any given chunk, then you CANNOT determine | |
1130 | the size of the previous chunk, and might even get a memory | |
1131 | addressing fault when trying to do so. | |
f65fd747 | 1132 | |
ae9166f2 FW |
1133 | The A (NON_MAIN_ARENA) bit is cleared for chunks on the initial, |
1134 | main arena, described by the main_arena variable. When additional | |
1135 | threads are spawned, each thread receives its own arena (up to a | |
1136 | configurable limit, after which arenas are reused for multiple | |
1137 | threads), and the chunks in these arenas have the A bit set. To | |
1138 | find the arena for a chunk on such a non-main arena, heap_for_ptr | |
1139 | performs a bit mask operation and indirection through the ar_ptr | |
1140 | member of the per-heap header heap_info (see arena.c). | |
1141 | ||
f65fd747 | 1142 | Note that the `foot' of the current chunk is actually represented |
fa8d436c UD |
1143 | as the prev_size of the NEXT chunk. This makes it easier to |
1144 | deal with alignments etc but can be very confusing when trying | |
1145 | to extend or adapt this code. | |
f65fd747 | 1146 | |
ae9166f2 | 1147 | The three exceptions to all this are: |
f65fd747 | 1148 | |
fa8d436c | 1149 | 1. The special chunk `top' doesn't bother using the |
72f90263 UD |
1150 | trailing size field since there is no next contiguous chunk |
1151 | that would have to index off it. After initialization, `top' | |
1152 | is forced to always exist. If it would become less than | |
1153 | MINSIZE bytes long, it is replenished. | |
f65fd747 UD |
1154 | |
1155 | 2. Chunks allocated via mmap, which have the second-lowest-order | |
72f90263 | 1156 | bit M (IS_MMAPPED) set in their size fields. Because they are |
ae9166f2 FW |
1157 | allocated one-by-one, each must contain its own trailing size |
1158 | field. If the M bit is set, the other bits are ignored | |
1159 | (because mmapped chunks are neither in an arena, nor adjacent | |
1160 | to a freed chunk). The M bit is also used for chunks which | |
1161 | originally came from a dumped heap via malloc_set_state in | |
1162 | hooks.c. | |
1163 | ||
1164 | 3. Chunks in fastbins are treated as allocated chunks from the | |
1165 | point of view of the chunk allocator. They are consolidated | |
1166 | with their neighbors only in bulk, in malloc_consolidate. | |
f65fd747 UD |
1167 | */ |
1168 | ||
1169 | /* | |
fa8d436c UD |
1170 | ---------- Size and alignment checks and conversions ---------- |
1171 | */ | |
f65fd747 | 1172 | |
fa8d436c | 1173 | /* conversion from malloc headers to user pointers, and back */ |
f65fd747 | 1174 | |
22a89187 | 1175 | #define chunk2mem(p) ((void*)((char*)(p) + 2*SIZE_SZ)) |
fa8d436c | 1176 | #define mem2chunk(mem) ((mchunkptr)((char*)(mem) - 2*SIZE_SZ)) |
f65fd747 | 1177 | |
fa8d436c | 1178 | /* The smallest possible chunk */ |
7ecfbd38 | 1179 | #define MIN_CHUNK_SIZE (offsetof(struct malloc_chunk, fd_nextsize)) |
f65fd747 | 1180 | |
fa8d436c | 1181 | /* The smallest size we can malloc is an aligned minimal chunk */ |
f65fd747 | 1182 | |
fa8d436c UD |
1183 | #define MINSIZE \ |
1184 | (unsigned long)(((MIN_CHUNK_SIZE+MALLOC_ALIGN_MASK) & ~MALLOC_ALIGN_MASK)) | |
f65fd747 | 1185 | |
fa8d436c | 1186 | /* Check if m has acceptable alignment */ |
f65fd747 | 1187 | |
073f560e UD |
1188 | #define aligned_OK(m) (((unsigned long)(m) & MALLOC_ALIGN_MASK) == 0) |
1189 | ||
1190 | #define misaligned_chunk(p) \ | |
1191 | ((uintptr_t)(MALLOC_ALIGNMENT == 2 * SIZE_SZ ? (p) : chunk2mem (p)) \ | |
1192 | & MALLOC_ALIGN_MASK) | |
f65fd747 | 1193 | |
f65fd747 | 1194 | |
a9177ff5 | 1195 | /* |
fa8d436c UD |
1196 | Check if a request is so large that it would wrap around zero when |
1197 | padded and aligned. To simplify some other code, the bound is made | |
1198 | low enough so that adding MINSIZE will also not wrap around zero. | |
6c8dbf00 | 1199 | */ |
f65fd747 | 1200 | |
fa8d436c | 1201 | #define REQUEST_OUT_OF_RANGE(req) \ |
6c8dbf00 OB |
1202 | ((unsigned long) (req) >= \ |
1203 | (unsigned long) (INTERNAL_SIZE_T) (-2 * MINSIZE)) | |
f65fd747 | 1204 | |
fa8d436c | 1205 | /* pad request bytes into a usable size -- internal version */ |
f65fd747 | 1206 | |
fa8d436c UD |
1207 | #define request2size(req) \ |
1208 | (((req) + SIZE_SZ + MALLOC_ALIGN_MASK < MINSIZE) ? \ | |
1209 | MINSIZE : \ | |
1210 | ((req) + SIZE_SZ + MALLOC_ALIGN_MASK) & ~MALLOC_ALIGN_MASK) | |
f65fd747 | 1211 | |
8e448310 AS |
1212 | /* Same, except also perform an argument and result check. First, we check |
1213 | that the padding done by request2size didn't result in an integer | |
1214 | overflow. Then we check (using REQUEST_OUT_OF_RANGE) that the resulting | |
1215 | size isn't so large that a later alignment would lead to another integer | |
1216 | overflow. */ | |
1217 | #define checked_request2size(req, sz) \ | |
1218 | ({ \ | |
1219 | (sz) = request2size (req); \ | |
1220 | if (((sz) < (req)) \ | |
1221 | || REQUEST_OUT_OF_RANGE (sz)) \ | |
1222 | { \ | |
1223 | __set_errno (ENOMEM); \ | |
1224 | return 0; \ | |
1225 | } \ | |
1226 | }) | |
f65fd747 UD |
1227 | |
1228 | /* | |
6c8dbf00 OB |
1229 | --------------- Physical chunk operations --------------- |
1230 | */ | |
f65fd747 | 1231 | |
10dc2a90 | 1232 | |
fa8d436c UD |
1233 | /* size field is or'ed with PREV_INUSE when previous adjacent chunk in use */ |
1234 | #define PREV_INUSE 0x1 | |
f65fd747 | 1235 | |
fa8d436c | 1236 | /* extract inuse bit of previous chunk */ |
e9c4fe93 | 1237 | #define prev_inuse(p) ((p)->mchunk_size & PREV_INUSE) |
f65fd747 | 1238 | |
f65fd747 | 1239 | |
fa8d436c UD |
1240 | /* size field is or'ed with IS_MMAPPED if the chunk was obtained with mmap() */ |
1241 | #define IS_MMAPPED 0x2 | |
f65fd747 | 1242 | |
fa8d436c | 1243 | /* check for mmap()'ed chunk */ |
e9c4fe93 | 1244 | #define chunk_is_mmapped(p) ((p)->mchunk_size & IS_MMAPPED) |
f65fd747 | 1245 | |
f65fd747 | 1246 | |
fa8d436c UD |
1247 | /* size field is or'ed with NON_MAIN_ARENA if the chunk was obtained |
1248 | from a non-main arena. This is only set immediately before handing | |
1249 | the chunk to the user, if necessary. */ | |
1250 | #define NON_MAIN_ARENA 0x4 | |
f65fd747 | 1251 | |
ae9166f2 | 1252 | /* Check for chunk from main arena. */ |
e9c4fe93 FW |
1253 | #define chunk_main_arena(p) (((p)->mchunk_size & NON_MAIN_ARENA) == 0) |
1254 | ||
1255 | /* Mark a chunk as not being on the main arena. */ | |
1256 | #define set_non_main_arena(p) ((p)->mchunk_size |= NON_MAIN_ARENA) | |
f65fd747 UD |
1257 | |
1258 | ||
a9177ff5 | 1259 | /* |
6c8dbf00 | 1260 | Bits to mask off when extracting size |
f65fd747 | 1261 | |
6c8dbf00 OB |
1262 | Note: IS_MMAPPED is intentionally not masked off from size field in |
1263 | macros for which mmapped chunks should never be seen. This should | |
1264 | cause helpful core dumps to occur if it is tried by accident by | |
1265 | people extending or adapting this malloc. | |
1266 | */ | |
1267 | #define SIZE_BITS (PREV_INUSE | IS_MMAPPED | NON_MAIN_ARENA) | |
f65fd747 | 1268 | |
fa8d436c | 1269 | /* Get size, ignoring use bits */ |
e9c4fe93 | 1270 | #define chunksize(p) (chunksize_nomask (p) & ~(SIZE_BITS)) |
f65fd747 | 1271 | |
e9c4fe93 FW |
1272 | /* Like chunksize, but do not mask SIZE_BITS. */ |
1273 | #define chunksize_nomask(p) ((p)->mchunk_size) | |
f65fd747 | 1274 | |
fa8d436c | 1275 | /* Ptr to next physical malloc_chunk. */ |
e9c4fe93 FW |
1276 | #define next_chunk(p) ((mchunkptr) (((char *) (p)) + chunksize (p))) |
1277 | ||
229855e5 | 1278 | /* Size of the chunk below P. Only valid if !prev_inuse (P). */ |
e9c4fe93 FW |
1279 | #define prev_size(p) ((p)->mchunk_prev_size) |
1280 | ||
229855e5 | 1281 | /* Set the size of the chunk below P. Only valid if !prev_inuse (P). */ |
e9c4fe93 | 1282 | #define set_prev_size(p, sz) ((p)->mchunk_prev_size = (sz)) |
f65fd747 | 1283 | |
229855e5 | 1284 | /* Ptr to previous physical malloc_chunk. Only valid if !prev_inuse (P). */ |
e9c4fe93 | 1285 | #define prev_chunk(p) ((mchunkptr) (((char *) (p)) - prev_size (p))) |
f65fd747 | 1286 | |
fa8d436c | 1287 | /* Treat space at ptr + offset as a chunk */ |
6c8dbf00 | 1288 | #define chunk_at_offset(p, s) ((mchunkptr) (((char *) (p)) + (s))) |
fa8d436c UD |
1289 | |
1290 | /* extract p's inuse bit */ | |
6c8dbf00 | 1291 | #define inuse(p) \ |
e9c4fe93 | 1292 | ((((mchunkptr) (((char *) (p)) + chunksize (p)))->mchunk_size) & PREV_INUSE) |
f65fd747 | 1293 | |
fa8d436c | 1294 | /* set/clear chunk as being inuse without otherwise disturbing */ |
6c8dbf00 | 1295 | #define set_inuse(p) \ |
e9c4fe93 | 1296 | ((mchunkptr) (((char *) (p)) + chunksize (p)))->mchunk_size |= PREV_INUSE |
f65fd747 | 1297 | |
6c8dbf00 | 1298 | #define clear_inuse(p) \ |
e9c4fe93 | 1299 | ((mchunkptr) (((char *) (p)) + chunksize (p)))->mchunk_size &= ~(PREV_INUSE) |
f65fd747 UD |
1300 | |
1301 | ||
fa8d436c | 1302 | /* check/set/clear inuse bits in known places */ |
6c8dbf00 | 1303 | #define inuse_bit_at_offset(p, s) \ |
e9c4fe93 | 1304 | (((mchunkptr) (((char *) (p)) + (s)))->mchunk_size & PREV_INUSE) |
f65fd747 | 1305 | |
6c8dbf00 | 1306 | #define set_inuse_bit_at_offset(p, s) \ |
e9c4fe93 | 1307 | (((mchunkptr) (((char *) (p)) + (s)))->mchunk_size |= PREV_INUSE) |
f65fd747 | 1308 | |
6c8dbf00 | 1309 | #define clear_inuse_bit_at_offset(p, s) \ |
e9c4fe93 | 1310 | (((mchunkptr) (((char *) (p)) + (s)))->mchunk_size &= ~(PREV_INUSE)) |
f65fd747 | 1311 | |
f65fd747 | 1312 | |
fa8d436c | 1313 | /* Set size at head, without disturbing its use bit */ |
e9c4fe93 | 1314 | #define set_head_size(p, s) ((p)->mchunk_size = (((p)->mchunk_size & SIZE_BITS) | (s))) |
f65fd747 | 1315 | |
fa8d436c | 1316 | /* Set size/use field */ |
e9c4fe93 | 1317 | #define set_head(p, s) ((p)->mchunk_size = (s)) |
f65fd747 | 1318 | |
fa8d436c | 1319 | /* Set size at footer (only when chunk is not in use) */ |
e9c4fe93 | 1320 | #define set_foot(p, s) (((mchunkptr) ((char *) (p) + (s)))->mchunk_prev_size = (s)) |
f65fd747 UD |
1321 | |
1322 | ||
e9c4fe93 FW |
1323 | #pragma GCC poison mchunk_size |
1324 | #pragma GCC poison mchunk_prev_size | |
1325 | ||
fa8d436c | 1326 | /* |
6c8dbf00 | 1327 | -------------------- Internal data structures -------------------- |
fa8d436c UD |
1328 | |
1329 | All internal state is held in an instance of malloc_state defined | |
1330 | below. There are no other static variables, except in two optional | |
a9177ff5 | 1331 | cases: |
6c8dbf00 OB |
1332 | * If USE_MALLOC_LOCK is defined, the mALLOC_MUTEx declared above. |
1333 | * If mmap doesn't support MAP_ANONYMOUS, a dummy file descriptor | |
22a89187 | 1334 | for mmap. |
fa8d436c UD |
1335 | |
1336 | Beware of lots of tricks that minimize the total bookkeeping space | |
1337 | requirements. The result is a little over 1K bytes (for 4byte | |
1338 | pointers and size_t.) | |
6c8dbf00 | 1339 | */ |
f65fd747 UD |
1340 | |
1341 | /* | |
6c8dbf00 | 1342 | Bins |
fa8d436c UD |
1343 | |
1344 | An array of bin headers for free chunks. Each bin is doubly | |
1345 | linked. The bins are approximately proportionally (log) spaced. | |
1346 | There are a lot of these bins (128). This may look excessive, but | |
1347 | works very well in practice. Most bins hold sizes that are | |
1348 | unusual as malloc request sizes, but are more usual for fragments | |
1349 | and consolidated sets of chunks, which is what these bins hold, so | |
1350 | they can be found quickly. All procedures maintain the invariant | |
1351 | that no consolidated chunk physically borders another one, so each | |
1352 | chunk in a list is known to be preceeded and followed by either | |
1353 | inuse chunks or the ends of memory. | |
1354 | ||
1355 | Chunks in bins are kept in size order, with ties going to the | |
1356 | approximately least recently used chunk. Ordering isn't needed | |
1357 | for the small bins, which all contain the same-sized chunks, but | |
1358 | facilitates best-fit allocation for larger chunks. These lists | |
1359 | are just sequential. Keeping them in order almost never requires | |
1360 | enough traversal to warrant using fancier ordered data | |
a9177ff5 | 1361 | structures. |
fa8d436c UD |
1362 | |
1363 | Chunks of the same size are linked with the most | |
1364 | recently freed at the front, and allocations are taken from the | |
1365 | back. This results in LRU (FIFO) allocation order, which tends | |
1366 | to give each chunk an equal opportunity to be consolidated with | |
1367 | adjacent freed chunks, resulting in larger free chunks and less | |
1368 | fragmentation. | |
1369 | ||
1370 | To simplify use in double-linked lists, each bin header acts | |
1371 | as a malloc_chunk. This avoids special-casing for headers. | |
1372 | But to conserve space and improve locality, we allocate | |
1373 | only the fd/bk pointers of bins, and then use repositioning tricks | |
a9177ff5 | 1374 | to treat these as the fields of a malloc_chunk*. |
6c8dbf00 | 1375 | */ |
f65fd747 | 1376 | |
6c8dbf00 | 1377 | typedef struct malloc_chunk *mbinptr; |
f65fd747 | 1378 | |
fa8d436c | 1379 | /* addressing -- note that bin_at(0) does not exist */ |
41999a1a UD |
1380 | #define bin_at(m, i) \ |
1381 | (mbinptr) (((char *) &((m)->bins[((i) - 1) * 2])) \ | |
6c8dbf00 | 1382 | - offsetof (struct malloc_chunk, fd)) |
f65fd747 | 1383 | |
fa8d436c | 1384 | /* analog of ++bin */ |
6c8dbf00 | 1385 | #define next_bin(b) ((mbinptr) ((char *) (b) + (sizeof (mchunkptr) << 1))) |
f65fd747 | 1386 | |
fa8d436c UD |
1387 | /* Reminders about list directionality within bins */ |
1388 | #define first(b) ((b)->fd) | |
1389 | #define last(b) ((b)->bk) | |
f65fd747 | 1390 | |
fa8d436c | 1391 | /* |
6c8dbf00 | 1392 | Indexing |
fa8d436c UD |
1393 | |
1394 | Bins for sizes < 512 bytes contain chunks of all the same size, spaced | |
1395 | 8 bytes apart. Larger bins are approximately logarithmically spaced: | |
f65fd747 | 1396 | |
fa8d436c UD |
1397 | 64 bins of size 8 |
1398 | 32 bins of size 64 | |
1399 | 16 bins of size 512 | |
1400 | 8 bins of size 4096 | |
1401 | 4 bins of size 32768 | |
1402 | 2 bins of size 262144 | |
1403 | 1 bin of size what's left | |
f65fd747 | 1404 | |
fa8d436c UD |
1405 | There is actually a little bit of slop in the numbers in bin_index |
1406 | for the sake of speed. This makes no difference elsewhere. | |
f65fd747 | 1407 | |
fa8d436c UD |
1408 | The bins top out around 1MB because we expect to service large |
1409 | requests via mmap. | |
b5a2bbe6 L |
1410 | |
1411 | Bin 0 does not exist. Bin 1 is the unordered list; if that would be | |
1412 | a valid chunk size the small bins are bumped up one. | |
6c8dbf00 | 1413 | */ |
f65fd747 | 1414 | |
fa8d436c UD |
1415 | #define NBINS 128 |
1416 | #define NSMALLBINS 64 | |
1d47e92f | 1417 | #define SMALLBIN_WIDTH MALLOC_ALIGNMENT |
b5a2bbe6 L |
1418 | #define SMALLBIN_CORRECTION (MALLOC_ALIGNMENT > 2 * SIZE_SZ) |
1419 | #define MIN_LARGE_SIZE ((NSMALLBINS - SMALLBIN_CORRECTION) * SMALLBIN_WIDTH) | |
f65fd747 | 1420 | |
fa8d436c | 1421 | #define in_smallbin_range(sz) \ |
6c8dbf00 | 1422 | ((unsigned long) (sz) < (unsigned long) MIN_LARGE_SIZE) |
f65fd747 | 1423 | |
1d47e92f | 1424 | #define smallbin_index(sz) \ |
6c8dbf00 | 1425 | ((SMALLBIN_WIDTH == 16 ? (((unsigned) (sz)) >> 4) : (((unsigned) (sz)) >> 3))\ |
b5a2bbe6 | 1426 | + SMALLBIN_CORRECTION) |
f65fd747 | 1427 | |
1d47e92f | 1428 | #define largebin_index_32(sz) \ |
6c8dbf00 OB |
1429 | (((((unsigned long) (sz)) >> 6) <= 38) ? 56 + (((unsigned long) (sz)) >> 6) :\ |
1430 | ((((unsigned long) (sz)) >> 9) <= 20) ? 91 + (((unsigned long) (sz)) >> 9) :\ | |
1431 | ((((unsigned long) (sz)) >> 12) <= 10) ? 110 + (((unsigned long) (sz)) >> 12) :\ | |
1432 | ((((unsigned long) (sz)) >> 15) <= 4) ? 119 + (((unsigned long) (sz)) >> 15) :\ | |
1433 | ((((unsigned long) (sz)) >> 18) <= 2) ? 124 + (((unsigned long) (sz)) >> 18) :\ | |
1434 | 126) | |
f65fd747 | 1435 | |
b5a2bbe6 | 1436 | #define largebin_index_32_big(sz) \ |
6c8dbf00 OB |
1437 | (((((unsigned long) (sz)) >> 6) <= 45) ? 49 + (((unsigned long) (sz)) >> 6) :\ |
1438 | ((((unsigned long) (sz)) >> 9) <= 20) ? 91 + (((unsigned long) (sz)) >> 9) :\ | |
1439 | ((((unsigned long) (sz)) >> 12) <= 10) ? 110 + (((unsigned long) (sz)) >> 12) :\ | |
1440 | ((((unsigned long) (sz)) >> 15) <= 4) ? 119 + (((unsigned long) (sz)) >> 15) :\ | |
1441 | ((((unsigned long) (sz)) >> 18) <= 2) ? 124 + (((unsigned long) (sz)) >> 18) :\ | |
1442 | 126) | |
b5a2bbe6 | 1443 | |
1d47e92f UD |
1444 | // XXX It remains to be seen whether it is good to keep the widths of |
1445 | // XXX the buckets the same or whether it should be scaled by a factor | |
1446 | // XXX of two as well. | |
1447 | #define largebin_index_64(sz) \ | |
6c8dbf00 OB |
1448 | (((((unsigned long) (sz)) >> 6) <= 48) ? 48 + (((unsigned long) (sz)) >> 6) :\ |
1449 | ((((unsigned long) (sz)) >> 9) <= 20) ? 91 + (((unsigned long) (sz)) >> 9) :\ | |
1450 | ((((unsigned long) (sz)) >> 12) <= 10) ? 110 + (((unsigned long) (sz)) >> 12) :\ | |
1451 | ((((unsigned long) (sz)) >> 15) <= 4) ? 119 + (((unsigned long) (sz)) >> 15) :\ | |
1452 | ((((unsigned long) (sz)) >> 18) <= 2) ? 124 + (((unsigned long) (sz)) >> 18) :\ | |
1453 | 126) | |
1d47e92f UD |
1454 | |
1455 | #define largebin_index(sz) \ | |
b5a2bbe6 L |
1456 | (SIZE_SZ == 8 ? largebin_index_64 (sz) \ |
1457 | : MALLOC_ALIGNMENT == 16 ? largebin_index_32_big (sz) \ | |
1458 | : largebin_index_32 (sz)) | |
1d47e92f | 1459 | |
fa8d436c | 1460 | #define bin_index(sz) \ |
6c8dbf00 | 1461 | ((in_smallbin_range (sz)) ? smallbin_index (sz) : largebin_index (sz)) |
f65fd747 | 1462 | |
1ecba1fa FW |
1463 | /* Take a chunk off a bin list. */ |
1464 | static void | |
1465 | unlink_chunk (mstate av, mchunkptr p) | |
1466 | { | |
1467 | if (chunksize (p) != prev_size (next_chunk (p))) | |
1468 | malloc_printerr ("corrupted size vs. prev_size"); | |
1469 | ||
1470 | mchunkptr fd = p->fd; | |
1471 | mchunkptr bk = p->bk; | |
1472 | ||
1473 | if (__builtin_expect (fd->bk != p || bk->fd != p, 0)) | |
1474 | malloc_printerr ("corrupted double-linked list"); | |
1475 | ||
1476 | fd->bk = bk; | |
1477 | bk->fd = fd; | |
1478 | if (!in_smallbin_range (chunksize_nomask (p)) && p->fd_nextsize != NULL) | |
1479 | { | |
1480 | if (p->fd_nextsize->bk_nextsize != p | |
1481 | || p->bk_nextsize->fd_nextsize != p) | |
1482 | malloc_printerr ("corrupted double-linked list (not small)"); | |
1483 | ||
1484 | if (fd->fd_nextsize == NULL) | |
1485 | { | |
1486 | if (p->fd_nextsize == p) | |
1487 | fd->fd_nextsize = fd->bk_nextsize = fd; | |
1488 | else | |
1489 | { | |
1490 | fd->fd_nextsize = p->fd_nextsize; | |
1491 | fd->bk_nextsize = p->bk_nextsize; | |
1492 | p->fd_nextsize->bk_nextsize = fd; | |
1493 | p->bk_nextsize->fd_nextsize = fd; | |
1494 | } | |
1495 | } | |
1496 | else | |
1497 | { | |
1498 | p->fd_nextsize->bk_nextsize = p->bk_nextsize; | |
1499 | p->bk_nextsize->fd_nextsize = p->fd_nextsize; | |
1500 | } | |
1501 | } | |
1502 | } | |
f65fd747 UD |
1503 | |
1504 | /* | |
6c8dbf00 | 1505 | Unsorted chunks |
fa8d436c UD |
1506 | |
1507 | All remainders from chunk splits, as well as all returned chunks, | |
1508 | are first placed in the "unsorted" bin. They are then placed | |
1509 | in regular bins after malloc gives them ONE chance to be used before | |
1510 | binning. So, basically, the unsorted_chunks list acts as a queue, | |
1511 | with chunks being placed on it in free (and malloc_consolidate), | |
1512 | and taken off (to be either used or placed in bins) in malloc. | |
1513 | ||
1514 | The NON_MAIN_ARENA flag is never set for unsorted chunks, so it | |
1515 | does not have to be taken into account in size comparisons. | |
6c8dbf00 | 1516 | */ |
f65fd747 | 1517 | |
fa8d436c | 1518 | /* The otherwise unindexable 1-bin is used to hold unsorted chunks. */ |
6c8dbf00 | 1519 | #define unsorted_chunks(M) (bin_at (M, 1)) |
f65fd747 | 1520 | |
fa8d436c | 1521 | /* |
6c8dbf00 | 1522 | Top |
fa8d436c UD |
1523 | |
1524 | The top-most available chunk (i.e., the one bordering the end of | |
1525 | available memory) is treated specially. It is never included in | |
1526 | any bin, is used only if no other chunk is available, and is | |
1527 | released back to the system if it is very large (see | |
1528 | M_TRIM_THRESHOLD). Because top initially | |
1529 | points to its own bin with initial zero size, thus forcing | |
1530 | extension on the first malloc request, we avoid having any special | |
1531 | code in malloc to check whether it even exists yet. But we still | |
1532 | need to do so when getting memory from system, so we make | |
1533 | initial_top treat the bin as a legal but unusable chunk during the | |
1534 | interval between initialization and the first call to | |
3b49edc0 | 1535 | sysmalloc. (This is somewhat delicate, since it relies on |
fa8d436c | 1536 | the 2 preceding words to be zero during this interval as well.) |
6c8dbf00 | 1537 | */ |
f65fd747 | 1538 | |
fa8d436c | 1539 | /* Conveniently, the unsorted bin can be used as dummy top on first call */ |
6c8dbf00 | 1540 | #define initial_top(M) (unsorted_chunks (M)) |
f65fd747 | 1541 | |
fa8d436c | 1542 | /* |
6c8dbf00 | 1543 | Binmap |
f65fd747 | 1544 | |
fa8d436c UD |
1545 | To help compensate for the large number of bins, a one-level index |
1546 | structure is used for bin-by-bin searching. `binmap' is a | |
1547 | bitvector recording whether bins are definitely empty so they can | |
1548 | be skipped over during during traversals. The bits are NOT always | |
1549 | cleared as soon as bins are empty, but instead only | |
1550 | when they are noticed to be empty during traversal in malloc. | |
6c8dbf00 | 1551 | */ |
f65fd747 | 1552 | |
fa8d436c UD |
1553 | /* Conservatively use 32 bits per map word, even if on 64bit system */ |
1554 | #define BINMAPSHIFT 5 | |
1555 | #define BITSPERMAP (1U << BINMAPSHIFT) | |
1556 | #define BINMAPSIZE (NBINS / BITSPERMAP) | |
f65fd747 | 1557 | |
fa8d436c | 1558 | #define idx2block(i) ((i) >> BINMAPSHIFT) |
6c8dbf00 | 1559 | #define idx2bit(i) ((1U << ((i) & ((1U << BINMAPSHIFT) - 1)))) |
f65fd747 | 1560 | |
6c8dbf00 OB |
1561 | #define mark_bin(m, i) ((m)->binmap[idx2block (i)] |= idx2bit (i)) |
1562 | #define unmark_bin(m, i) ((m)->binmap[idx2block (i)] &= ~(idx2bit (i))) | |
1563 | #define get_binmap(m, i) ((m)->binmap[idx2block (i)] & idx2bit (i)) | |
f65fd747 | 1564 | |
fa8d436c | 1565 | /* |
6c8dbf00 | 1566 | Fastbins |
fa8d436c UD |
1567 | |
1568 | An array of lists holding recently freed small chunks. Fastbins | |
1569 | are not doubly linked. It is faster to single-link them, and | |
1570 | since chunks are never removed from the middles of these lists, | |
1571 | double linking is not necessary. Also, unlike regular bins, they | |
1572 | are not even processed in FIFO order (they use faster LIFO) since | |
1573 | ordering doesn't much matter in the transient contexts in which | |
1574 | fastbins are normally used. | |
1575 | ||
1576 | Chunks in fastbins keep their inuse bit set, so they cannot | |
1577 | be consolidated with other free chunks. malloc_consolidate | |
1578 | releases all chunks in fastbins and consolidates them with | |
a9177ff5 | 1579 | other free chunks. |
6c8dbf00 | 1580 | */ |
f65fd747 | 1581 | |
6c8dbf00 | 1582 | typedef struct malloc_chunk *mfastbinptr; |
425ce2ed | 1583 | #define fastbin(ar_ptr, idx) ((ar_ptr)->fastbinsY[idx]) |
f65fd747 | 1584 | |
fa8d436c | 1585 | /* offset 2 to use otherwise unindexable first 2 bins */ |
425ce2ed | 1586 | #define fastbin_index(sz) \ |
6c8dbf00 | 1587 | ((((unsigned int) (sz)) >> (SIZE_SZ == 8 ? 4 : 3)) - 2) |
425ce2ed | 1588 | |
f65fd747 | 1589 | |
fa8d436c | 1590 | /* The maximum fastbin request size we support */ |
425ce2ed | 1591 | #define MAX_FAST_SIZE (80 * SIZE_SZ / 4) |
f65fd747 | 1592 | |
6c8dbf00 | 1593 | #define NFASTBINS (fastbin_index (request2size (MAX_FAST_SIZE)) + 1) |
f65fd747 UD |
1594 | |
1595 | /* | |
6c8dbf00 OB |
1596 | FASTBIN_CONSOLIDATION_THRESHOLD is the size of a chunk in free() |
1597 | that triggers automatic consolidation of possibly-surrounding | |
1598 | fastbin chunks. This is a heuristic, so the exact value should not | |
1599 | matter too much. It is defined at half the default trim threshold as a | |
1600 | compromise heuristic to only attempt consolidation if it is likely | |
1601 | to lead to trimming. However, it is not dynamically tunable, since | |
1602 | consolidation reduces fragmentation surrounding large chunks even | |
1603 | if trimming is not used. | |
1604 | */ | |
f65fd747 | 1605 | |
fa8d436c | 1606 | #define FASTBIN_CONSOLIDATION_THRESHOLD (65536UL) |
f65fd747 | 1607 | |
f65fd747 | 1608 | /* |
6c8dbf00 OB |
1609 | NONCONTIGUOUS_BIT indicates that MORECORE does not return contiguous |
1610 | regions. Otherwise, contiguity is exploited in merging together, | |
1611 | when possible, results from consecutive MORECORE calls. | |
f65fd747 | 1612 | |
6c8dbf00 OB |
1613 | The initial value comes from MORECORE_CONTIGUOUS, but is |
1614 | changed dynamically if mmap is ever used as an sbrk substitute. | |
1615 | */ | |
f65fd747 | 1616 | |
fa8d436c | 1617 | #define NONCONTIGUOUS_BIT (2U) |
f65fd747 | 1618 | |
6c8dbf00 OB |
1619 | #define contiguous(M) (((M)->flags & NONCONTIGUOUS_BIT) == 0) |
1620 | #define noncontiguous(M) (((M)->flags & NONCONTIGUOUS_BIT) != 0) | |
1621 | #define set_noncontiguous(M) ((M)->flags |= NONCONTIGUOUS_BIT) | |
9bf248c6 | 1622 | #define set_contiguous(M) ((M)->flags &= ~NONCONTIGUOUS_BIT) |
f65fd747 | 1623 | |
eac43cbb FW |
1624 | /* Maximum size of memory handled in fastbins. */ |
1625 | static INTERNAL_SIZE_T global_max_fast; | |
1626 | ||
a9177ff5 RM |
1627 | /* |
1628 | Set value of max_fast. | |
fa8d436c | 1629 | Use impossibly small value if 0. |
3381be5c WD |
1630 | Precondition: there are no existing fastbin chunks in the main arena. |
1631 | Since do_check_malloc_state () checks this, we call malloc_consolidate () | |
1632 | before changing max_fast. Note other arenas will leak their fast bin | |
1633 | entries if max_fast is reduced. | |
6c8dbf00 | 1634 | */ |
f65fd747 | 1635 | |
9bf248c6 | 1636 | #define set_max_fast(s) \ |
991eda1e | 1637 | global_max_fast = (((s) == 0) \ |
6c8dbf00 | 1638 | ? SMALLBIN_WIDTH : ((s + SIZE_SZ) & ~MALLOC_ALIGN_MASK)) |
f65fd747 | 1639 | |
eac43cbb FW |
1640 | static inline INTERNAL_SIZE_T |
1641 | get_max_fast (void) | |
1642 | { | |
1643 | /* Tell the GCC optimizers that global_max_fast is never larger | |
1644 | than MAX_FAST_SIZE. This avoids out-of-bounds array accesses in | |
1645 | _int_malloc after constant propagation of the size parameter. | |
1646 | (The code never executes because malloc preserves the | |
1647 | global_max_fast invariant, but the optimizers may not recognize | |
1648 | this.) */ | |
1649 | if (global_max_fast > MAX_FAST_SIZE) | |
1650 | __builtin_unreachable (); | |
1651 | return global_max_fast; | |
1652 | } | |
f65fd747 UD |
1653 | |
1654 | /* | |
fa8d436c | 1655 | ----------- Internal state representation and initialization ----------- |
6c8dbf00 | 1656 | */ |
f65fd747 | 1657 | |
e956075a WD |
1658 | /* |
1659 | have_fastchunks indicates that there are probably some fastbin chunks. | |
1660 | It is set true on entering a chunk into any fastbin, and cleared early in | |
1661 | malloc_consolidate. The value is approximate since it may be set when there | |
1662 | are no fastbin chunks, or it may be clear even if there are fastbin chunks | |
1663 | available. Given it's sole purpose is to reduce number of redundant calls to | |
1664 | malloc_consolidate, it does not affect correctness. As a result we can safely | |
1665 | use relaxed atomic accesses. | |
1666 | */ | |
1667 | ||
1668 | ||
6c8dbf00 OB |
1669 | struct malloc_state |
1670 | { | |
fa8d436c | 1671 | /* Serialize access. */ |
cbb47fa1 | 1672 | __libc_lock_define (, mutex); |
9bf248c6 UD |
1673 | |
1674 | /* Flags (formerly in max_fast). */ | |
1675 | int flags; | |
f65fd747 | 1676 | |
e956075a | 1677 | /* Set if the fastbin chunks contain recently inserted free blocks. */ |
2c2245b9 WD |
1678 | /* Note this is a bool but not all targets support atomics on booleans. */ |
1679 | int have_fastchunks; | |
e956075a | 1680 | |
fa8d436c | 1681 | /* Fastbins */ |
6c8dbf00 | 1682 | mfastbinptr fastbinsY[NFASTBINS]; |
f65fd747 | 1683 | |
fa8d436c | 1684 | /* Base of the topmost chunk -- not otherwise kept in a bin */ |
6c8dbf00 | 1685 | mchunkptr top; |
f65fd747 | 1686 | |
fa8d436c | 1687 | /* The remainder from the most recent split of a small request */ |
6c8dbf00 | 1688 | mchunkptr last_remainder; |
f65fd747 | 1689 | |
fa8d436c | 1690 | /* Normal bins packed as described above */ |
6c8dbf00 | 1691 | mchunkptr bins[NBINS * 2 - 2]; |
f65fd747 | 1692 | |
fa8d436c | 1693 | /* Bitmap of bins */ |
6c8dbf00 | 1694 | unsigned int binmap[BINMAPSIZE]; |
f65fd747 | 1695 | |
fa8d436c UD |
1696 | /* Linked list */ |
1697 | struct malloc_state *next; | |
f65fd747 | 1698 | |
a62719ba | 1699 | /* Linked list for free arenas. Access to this field is serialized |
90c400bd | 1700 | by free_list_lock in arena.c. */ |
425ce2ed | 1701 | struct malloc_state *next_free; |
425ce2ed | 1702 | |
a62719ba | 1703 | /* Number of threads attached to this arena. 0 if the arena is on |
90c400bd FW |
1704 | the free list. Access to this field is serialized by |
1705 | free_list_lock in arena.c. */ | |
a62719ba FW |
1706 | INTERNAL_SIZE_T attached_threads; |
1707 | ||
fa8d436c UD |
1708 | /* Memory allocated from the system in this arena. */ |
1709 | INTERNAL_SIZE_T system_mem; | |
1710 | INTERNAL_SIZE_T max_system_mem; | |
1711 | }; | |
f65fd747 | 1712 | |
6c8dbf00 OB |
1713 | struct malloc_par |
1714 | { | |
fa8d436c | 1715 | /* Tunable parameters */ |
6c8dbf00 OB |
1716 | unsigned long trim_threshold; |
1717 | INTERNAL_SIZE_T top_pad; | |
1718 | INTERNAL_SIZE_T mmap_threshold; | |
1719 | INTERNAL_SIZE_T arena_test; | |
1720 | INTERNAL_SIZE_T arena_max; | |
fa8d436c UD |
1721 | |
1722 | /* Memory map support */ | |
6c8dbf00 OB |
1723 | int n_mmaps; |
1724 | int n_mmaps_max; | |
1725 | int max_n_mmaps; | |
1d05c2fb UD |
1726 | /* the mmap_threshold is dynamic, until the user sets |
1727 | it manually, at which point we need to disable any | |
1728 | dynamic behavior. */ | |
6c8dbf00 | 1729 | int no_dyn_threshold; |
fa8d436c | 1730 | |
fa8d436c | 1731 | /* Statistics */ |
6c8dbf00 | 1732 | INTERNAL_SIZE_T mmapped_mem; |
6c8dbf00 | 1733 | INTERNAL_SIZE_T max_mmapped_mem; |
fa8d436c UD |
1734 | |
1735 | /* First address handed out by MORECORE/sbrk. */ | |
6c8dbf00 | 1736 | char *sbrk_base; |
d5c3fafc DD |
1737 | |
1738 | #if USE_TCACHE | |
1739 | /* Maximum number of buckets to use. */ | |
1740 | size_t tcache_bins; | |
1741 | size_t tcache_max_bytes; | |
1742 | /* Maximum number of chunks in each bucket. */ | |
1743 | size_t tcache_count; | |
1744 | /* Maximum number of chunks to remove from the unsorted list, which | |
1745 | aren't used to prefill the cache. */ | |
1746 | size_t tcache_unsorted_limit; | |
1747 | #endif | |
fa8d436c | 1748 | }; |
f65fd747 | 1749 | |
fa8d436c UD |
1750 | /* There are several instances of this struct ("arenas") in this |
1751 | malloc. If you are adapting this malloc in a way that does NOT use | |
1752 | a static or mmapped malloc_state, you MUST explicitly zero-fill it | |
1753 | before using. This malloc relies on the property that malloc_state | |
1754 | is initialized to all zeroes (as is true of C statics). */ | |
f65fd747 | 1755 | |
02d46fc4 | 1756 | static struct malloc_state main_arena = |
6c8dbf00 | 1757 | { |
400e1226 | 1758 | .mutex = _LIBC_LOCK_INITIALIZER, |
a62719ba FW |
1759 | .next = &main_arena, |
1760 | .attached_threads = 1 | |
6c8dbf00 | 1761 | }; |
f65fd747 | 1762 | |
4cf6c72f FW |
1763 | /* These variables are used for undumping support. Chunked are marked |
1764 | as using mmap, but we leave them alone if they fall into this | |
1e8a8875 FW |
1765 | range. NB: The chunk size for these chunks only includes the |
1766 | initial size field (of SIZE_SZ bytes), there is no trailing size | |
1767 | field (unlike with regular mmapped chunks). */ | |
4cf6c72f FW |
1768 | static mchunkptr dumped_main_arena_start; /* Inclusive. */ |
1769 | static mchunkptr dumped_main_arena_end; /* Exclusive. */ | |
1770 | ||
1771 | /* True if the pointer falls into the dumped arena. Use this after | |
1772 | chunk_is_mmapped indicates a chunk is mmapped. */ | |
1773 | #define DUMPED_MAIN_ARENA_CHUNK(p) \ | |
1774 | ((p) >= dumped_main_arena_start && (p) < dumped_main_arena_end) | |
1775 | ||
fa8d436c | 1776 | /* There is only one instance of the malloc parameters. */ |
f65fd747 | 1777 | |
02d46fc4 | 1778 | static struct malloc_par mp_ = |
6c8dbf00 OB |
1779 | { |
1780 | .top_pad = DEFAULT_TOP_PAD, | |
1781 | .n_mmaps_max = DEFAULT_MMAP_MAX, | |
1782 | .mmap_threshold = DEFAULT_MMAP_THRESHOLD, | |
1783 | .trim_threshold = DEFAULT_TRIM_THRESHOLD, | |
1784 | #define NARENAS_FROM_NCORES(n) ((n) * (sizeof (long) == 4 ? 2 : 8)) | |
1785 | .arena_test = NARENAS_FROM_NCORES (1) | |
d5c3fafc DD |
1786 | #if USE_TCACHE |
1787 | , | |
1788 | .tcache_count = TCACHE_FILL_COUNT, | |
1789 | .tcache_bins = TCACHE_MAX_BINS, | |
1790 | .tcache_max_bytes = tidx2usize (TCACHE_MAX_BINS-1), | |
1791 | .tcache_unsorted_limit = 0 /* No limit. */ | |
1792 | #endif | |
6c8dbf00 | 1793 | }; |
f65fd747 | 1794 | |
fa8d436c | 1795 | /* |
6c8dbf00 | 1796 | Initialize a malloc_state struct. |
f65fd747 | 1797 | |
3381be5c WD |
1798 | This is called from ptmalloc_init () or from _int_new_arena () |
1799 | when creating a new arena. | |
6c8dbf00 | 1800 | */ |
f65fd747 | 1801 | |
6c8dbf00 OB |
1802 | static void |
1803 | malloc_init_state (mstate av) | |
fa8d436c | 1804 | { |
6c8dbf00 | 1805 | int i; |
fa8d436c | 1806 | mbinptr bin; |
a9177ff5 | 1807 | |
fa8d436c | 1808 | /* Establish circular links for normal bins */ |
6c8dbf00 OB |
1809 | for (i = 1; i < NBINS; ++i) |
1810 | { | |
1811 | bin = bin_at (av, i); | |
1812 | bin->fd = bin->bk = bin; | |
1813 | } | |
f65fd747 | 1814 | |
fa8d436c UD |
1815 | #if MORECORE_CONTIGUOUS |
1816 | if (av != &main_arena) | |
1817 | #endif | |
6c8dbf00 | 1818 | set_noncontiguous (av); |
9bf248c6 | 1819 | if (av == &main_arena) |
6c8dbf00 | 1820 | set_max_fast (DEFAULT_MXFAST); |
e956075a | 1821 | atomic_store_relaxed (&av->have_fastchunks, false); |
f65fd747 | 1822 | |
6c8dbf00 | 1823 | av->top = initial_top (av); |
fa8d436c | 1824 | } |
e9b3e3c5 | 1825 | |
a9177ff5 | 1826 | /* |
fa8d436c | 1827 | Other internal utilities operating on mstates |
6c8dbf00 | 1828 | */ |
f65fd747 | 1829 | |
6c8dbf00 OB |
1830 | static void *sysmalloc (INTERNAL_SIZE_T, mstate); |
1831 | static int systrim (size_t, mstate); | |
1832 | static void malloc_consolidate (mstate); | |
7e3be507 | 1833 | |
404d4cef RM |
1834 | |
1835 | /* -------------- Early definitions for debugging hooks ---------------- */ | |
1836 | ||
1837 | /* Define and initialize the hook variables. These weak definitions must | |
1838 | appear before any use of the variables in a function (arena.c uses one). */ | |
1839 | #ifndef weak_variable | |
404d4cef RM |
1840 | /* In GNU libc we want the hook variables to be weak definitions to |
1841 | avoid a problem with Emacs. */ | |
22a89187 | 1842 | # define weak_variable weak_function |
404d4cef RM |
1843 | #endif |
1844 | ||
1845 | /* Forward declarations. */ | |
6c8dbf00 OB |
1846 | static void *malloc_hook_ini (size_t sz, |
1847 | const void *caller) __THROW; | |
1848 | static void *realloc_hook_ini (void *ptr, size_t sz, | |
1849 | const void *caller) __THROW; | |
1850 | static void *memalign_hook_ini (size_t alignment, size_t sz, | |
1851 | const void *caller) __THROW; | |
404d4cef | 1852 | |
2ba3cfa1 | 1853 | #if HAVE_MALLOC_INIT_HOOK |
92e1ab0e FW |
1854 | void weak_variable (*__malloc_initialize_hook) (void) = NULL; |
1855 | compat_symbol (libc, __malloc_initialize_hook, | |
1856 | __malloc_initialize_hook, GLIBC_2_0); | |
2ba3cfa1 FW |
1857 | #endif |
1858 | ||
a222d91a | 1859 | void weak_variable (*__free_hook) (void *__ptr, |
6c8dbf00 | 1860 | const void *) = NULL; |
a222d91a | 1861 | void *weak_variable (*__malloc_hook) |
6c8dbf00 | 1862 | (size_t __size, const void *) = malloc_hook_ini; |
a222d91a | 1863 | void *weak_variable (*__realloc_hook) |
6c8dbf00 OB |
1864 | (void *__ptr, size_t __size, const void *) |
1865 | = realloc_hook_ini; | |
a222d91a | 1866 | void *weak_variable (*__memalign_hook) |
6c8dbf00 OB |
1867 | (size_t __alignment, size_t __size, const void *) |
1868 | = memalign_hook_ini; | |
06d6611a | 1869 | void weak_variable (*__after_morecore_hook) (void) = NULL; |
404d4cef | 1870 | |
0a947e06 FW |
1871 | /* This function is called from the arena shutdown hook, to free the |
1872 | thread cache (if it exists). */ | |
1873 | static void tcache_thread_shutdown (void); | |
404d4cef | 1874 | |
854278df UD |
1875 | /* ------------------ Testing support ----------------------------------*/ |
1876 | ||
1877 | static int perturb_byte; | |
1878 | ||
af102d95 | 1879 | static void |
e8349efd OB |
1880 | alloc_perturb (char *p, size_t n) |
1881 | { | |
1882 | if (__glibc_unlikely (perturb_byte)) | |
1883 | memset (p, perturb_byte ^ 0xff, n); | |
1884 | } | |
1885 | ||
af102d95 | 1886 | static void |
e8349efd OB |
1887 | free_perturb (char *p, size_t n) |
1888 | { | |
1889 | if (__glibc_unlikely (perturb_byte)) | |
1890 | memset (p, perturb_byte, n); | |
1891 | } | |
1892 | ||
854278df UD |
1893 | |
1894 | ||
3ea5be54 AO |
1895 | #include <stap-probe.h> |
1896 | ||
fa8d436c UD |
1897 | /* ------------------- Support for multiple arenas -------------------- */ |
1898 | #include "arena.c" | |
f65fd747 | 1899 | |
fa8d436c | 1900 | /* |
6c8dbf00 | 1901 | Debugging support |
f65fd747 | 1902 | |
6c8dbf00 OB |
1903 | These routines make a number of assertions about the states |
1904 | of data structures that should be true at all times. If any | |
1905 | are not true, it's very likely that a user program has somehow | |
1906 | trashed memory. (It's also possible that there is a coding error | |
1907 | in malloc. In which case, please report it!) | |
1908 | */ | |
ee74a442 | 1909 | |
6c8dbf00 | 1910 | #if !MALLOC_DEBUG |
d8f00d46 | 1911 | |
6c8dbf00 OB |
1912 | # define check_chunk(A, P) |
1913 | # define check_free_chunk(A, P) | |
1914 | # define check_inuse_chunk(A, P) | |
1915 | # define check_remalloced_chunk(A, P, N) | |
1916 | # define check_malloced_chunk(A, P, N) | |
1917 | # define check_malloc_state(A) | |
d8f00d46 | 1918 | |
fa8d436c | 1919 | #else |
ca34d7a7 | 1920 | |
6c8dbf00 OB |
1921 | # define check_chunk(A, P) do_check_chunk (A, P) |
1922 | # define check_free_chunk(A, P) do_check_free_chunk (A, P) | |
1923 | # define check_inuse_chunk(A, P) do_check_inuse_chunk (A, P) | |
1924 | # define check_remalloced_chunk(A, P, N) do_check_remalloced_chunk (A, P, N) | |
1925 | # define check_malloced_chunk(A, P, N) do_check_malloced_chunk (A, P, N) | |
1926 | # define check_malloc_state(A) do_check_malloc_state (A) | |
ca34d7a7 | 1927 | |
fa8d436c | 1928 | /* |
6c8dbf00 OB |
1929 | Properties of all chunks |
1930 | */ | |
ca34d7a7 | 1931 | |
6c8dbf00 OB |
1932 | static void |
1933 | do_check_chunk (mstate av, mchunkptr p) | |
ca34d7a7 | 1934 | { |
6c8dbf00 | 1935 | unsigned long sz = chunksize (p); |
fa8d436c | 1936 | /* min and max possible addresses assuming contiguous allocation */ |
6c8dbf00 OB |
1937 | char *max_address = (char *) (av->top) + chunksize (av->top); |
1938 | char *min_address = max_address - av->system_mem; | |
fa8d436c | 1939 | |
6c8dbf00 OB |
1940 | if (!chunk_is_mmapped (p)) |
1941 | { | |
1942 | /* Has legal address ... */ | |
1943 | if (p != av->top) | |
1944 | { | |
1945 | if (contiguous (av)) | |
1946 | { | |
1947 | assert (((char *) p) >= min_address); | |
1948 | assert (((char *) p + sz) <= ((char *) (av->top))); | |
1949 | } | |
1950 | } | |
1951 | else | |
1952 | { | |
1953 | /* top size is always at least MINSIZE */ | |
1954 | assert ((unsigned long) (sz) >= MINSIZE); | |
1955 | /* top predecessor always marked inuse */ | |
1956 | assert (prev_inuse (p)); | |
1957 | } | |
fa8d436c | 1958 | } |
4cf6c72f | 1959 | else if (!DUMPED_MAIN_ARENA_CHUNK (p)) |
6c8dbf00 OB |
1960 | { |
1961 | /* address is outside main heap */ | |
1962 | if (contiguous (av) && av->top != initial_top (av)) | |
1963 | { | |
1964 | assert (((char *) p) < min_address || ((char *) p) >= max_address); | |
1965 | } | |
1966 | /* chunk is page-aligned */ | |
e9c4fe93 | 1967 | assert (((prev_size (p) + sz) & (GLRO (dl_pagesize) - 1)) == 0); |
6c8dbf00 OB |
1968 | /* mem is aligned */ |
1969 | assert (aligned_OK (chunk2mem (p))); | |
fa8d436c | 1970 | } |
eb406346 UD |
1971 | } |
1972 | ||
fa8d436c | 1973 | /* |
6c8dbf00 OB |
1974 | Properties of free chunks |
1975 | */ | |
ee74a442 | 1976 | |
6c8dbf00 OB |
1977 | static void |
1978 | do_check_free_chunk (mstate av, mchunkptr p) | |
67c94753 | 1979 | { |
3381be5c | 1980 | INTERNAL_SIZE_T sz = chunksize_nomask (p) & ~(PREV_INUSE | NON_MAIN_ARENA); |
6c8dbf00 | 1981 | mchunkptr next = chunk_at_offset (p, sz); |
67c94753 | 1982 | |
6c8dbf00 | 1983 | do_check_chunk (av, p); |
67c94753 | 1984 | |
fa8d436c | 1985 | /* Chunk must claim to be free ... */ |
6c8dbf00 OB |
1986 | assert (!inuse (p)); |
1987 | assert (!chunk_is_mmapped (p)); | |
67c94753 | 1988 | |
fa8d436c | 1989 | /* Unless a special marker, must have OK fields */ |
6c8dbf00 OB |
1990 | if ((unsigned long) (sz) >= MINSIZE) |
1991 | { | |
1992 | assert ((sz & MALLOC_ALIGN_MASK) == 0); | |
1993 | assert (aligned_OK (chunk2mem (p))); | |
1994 | /* ... matching footer field */ | |
3381be5c | 1995 | assert (prev_size (next_chunk (p)) == sz); |
6c8dbf00 OB |
1996 | /* ... and is fully consolidated */ |
1997 | assert (prev_inuse (p)); | |
1998 | assert (next == av->top || inuse (next)); | |
1999 | ||
2000 | /* ... and has minimally sane links */ | |
2001 | assert (p->fd->bk == p); | |
2002 | assert (p->bk->fd == p); | |
2003 | } | |
fa8d436c | 2004 | else /* markers are always of size SIZE_SZ */ |
6c8dbf00 | 2005 | assert (sz == SIZE_SZ); |
67c94753 | 2006 | } |
67c94753 | 2007 | |
fa8d436c | 2008 | /* |
6c8dbf00 OB |
2009 | Properties of inuse chunks |
2010 | */ | |
fa8d436c | 2011 | |
6c8dbf00 OB |
2012 | static void |
2013 | do_check_inuse_chunk (mstate av, mchunkptr p) | |
f65fd747 | 2014 | { |
fa8d436c | 2015 | mchunkptr next; |
f65fd747 | 2016 | |
6c8dbf00 | 2017 | do_check_chunk (av, p); |
f65fd747 | 2018 | |
6c8dbf00 | 2019 | if (chunk_is_mmapped (p)) |
fa8d436c | 2020 | return; /* mmapped chunks have no next/prev */ |
ca34d7a7 | 2021 | |
fa8d436c | 2022 | /* Check whether it claims to be in use ... */ |
6c8dbf00 | 2023 | assert (inuse (p)); |
10dc2a90 | 2024 | |
6c8dbf00 | 2025 | next = next_chunk (p); |
10dc2a90 | 2026 | |
fa8d436c | 2027 | /* ... and is surrounded by OK chunks. |
6c8dbf00 OB |
2028 | Since more things can be checked with free chunks than inuse ones, |
2029 | if an inuse chunk borders them and debug is on, it's worth doing them. | |
2030 | */ | |
2031 | if (!prev_inuse (p)) | |
2032 | { | |
2033 | /* Note that we cannot even look at prev unless it is not inuse */ | |
2034 | mchunkptr prv = prev_chunk (p); | |
2035 | assert (next_chunk (prv) == p); | |
2036 | do_check_free_chunk (av, prv); | |
2037 | } | |
fa8d436c | 2038 | |
6c8dbf00 OB |
2039 | if (next == av->top) |
2040 | { | |
2041 | assert (prev_inuse (next)); | |
2042 | assert (chunksize (next) >= MINSIZE); | |
2043 | } | |
2044 | else if (!inuse (next)) | |
2045 | do_check_free_chunk (av, next); | |
10dc2a90 UD |
2046 | } |
2047 | ||
fa8d436c | 2048 | /* |
6c8dbf00 OB |
2049 | Properties of chunks recycled from fastbins |
2050 | */ | |
fa8d436c | 2051 | |
6c8dbf00 OB |
2052 | static void |
2053 | do_check_remalloced_chunk (mstate av, mchunkptr p, INTERNAL_SIZE_T s) | |
10dc2a90 | 2054 | { |
3381be5c | 2055 | INTERNAL_SIZE_T sz = chunksize_nomask (p) & ~(PREV_INUSE | NON_MAIN_ARENA); |
fa8d436c | 2056 | |
6c8dbf00 OB |
2057 | if (!chunk_is_mmapped (p)) |
2058 | { | |
2059 | assert (av == arena_for_chunk (p)); | |
e9c4fe93 | 2060 | if (chunk_main_arena (p)) |
6c8dbf00 | 2061 | assert (av == &main_arena); |
e9c4fe93 FW |
2062 | else |
2063 | assert (av != &main_arena); | |
6c8dbf00 | 2064 | } |
fa8d436c | 2065 | |
6c8dbf00 | 2066 | do_check_inuse_chunk (av, p); |
fa8d436c UD |
2067 | |
2068 | /* Legal size ... */ | |
6c8dbf00 OB |
2069 | assert ((sz & MALLOC_ALIGN_MASK) == 0); |
2070 | assert ((unsigned long) (sz) >= MINSIZE); | |
fa8d436c | 2071 | /* ... and alignment */ |
6c8dbf00 | 2072 | assert (aligned_OK (chunk2mem (p))); |
fa8d436c | 2073 | /* chunk is less than MINSIZE more than request */ |
6c8dbf00 OB |
2074 | assert ((long) (sz) - (long) (s) >= 0); |
2075 | assert ((long) (sz) - (long) (s + MINSIZE) < 0); | |
10dc2a90 UD |
2076 | } |
2077 | ||
fa8d436c | 2078 | /* |
6c8dbf00 OB |
2079 | Properties of nonrecycled chunks at the point they are malloced |
2080 | */ | |
fa8d436c | 2081 | |
6c8dbf00 OB |
2082 | static void |
2083 | do_check_malloced_chunk (mstate av, mchunkptr p, INTERNAL_SIZE_T s) | |
10dc2a90 | 2084 | { |
fa8d436c | 2085 | /* same as recycled case ... */ |
6c8dbf00 | 2086 | do_check_remalloced_chunk (av, p, s); |
10dc2a90 | 2087 | |
fa8d436c | 2088 | /* |
6c8dbf00 OB |
2089 | ... plus, must obey implementation invariant that prev_inuse is |
2090 | always true of any allocated chunk; i.e., that each allocated | |
2091 | chunk borders either a previously allocated and still in-use | |
2092 | chunk, or the base of its memory arena. This is ensured | |
2093 | by making all allocations from the `lowest' part of any found | |
2094 | chunk. This does not necessarily hold however for chunks | |
2095 | recycled via fastbins. | |
2096 | */ | |
2097 | ||
2098 | assert (prev_inuse (p)); | |
fa8d436c | 2099 | } |
10dc2a90 | 2100 | |
f65fd747 | 2101 | |
fa8d436c | 2102 | /* |
6c8dbf00 | 2103 | Properties of malloc_state. |
f65fd747 | 2104 | |
6c8dbf00 OB |
2105 | This may be useful for debugging malloc, as well as detecting user |
2106 | programmer errors that somehow write into malloc_state. | |
f65fd747 | 2107 | |
6c8dbf00 OB |
2108 | If you are extending or experimenting with this malloc, you can |
2109 | probably figure out how to hack this routine to print out or | |
2110 | display chunk addresses, sizes, bins, and other instrumentation. | |
2111 | */ | |
f65fd747 | 2112 | |
6c8dbf00 OB |
2113 | static void |
2114 | do_check_malloc_state (mstate av) | |
fa8d436c UD |
2115 | { |
2116 | int i; | |
2117 | mchunkptr p; | |
2118 | mchunkptr q; | |
2119 | mbinptr b; | |
fa8d436c UD |
2120 | unsigned int idx; |
2121 | INTERNAL_SIZE_T size; | |
2122 | unsigned long total = 0; | |
2123 | int max_fast_bin; | |
f65fd747 | 2124 | |
fa8d436c | 2125 | /* internal size_t must be no wider than pointer type */ |
6c8dbf00 | 2126 | assert (sizeof (INTERNAL_SIZE_T) <= sizeof (char *)); |
f65fd747 | 2127 | |
fa8d436c | 2128 | /* alignment is a power of 2 */ |
6c8dbf00 | 2129 | assert ((MALLOC_ALIGNMENT & (MALLOC_ALIGNMENT - 1)) == 0); |
f65fd747 | 2130 | |
3381be5c WD |
2131 | /* Check the arena is initialized. */ |
2132 | assert (av->top != 0); | |
2133 | ||
2134 | /* No memory has been allocated yet, so doing more tests is not possible. */ | |
2135 | if (av->top == initial_top (av)) | |
fa8d436c | 2136 | return; |
f65fd747 | 2137 | |
fa8d436c | 2138 | /* pagesize is a power of 2 */ |
8a35c3fe | 2139 | assert (powerof2(GLRO (dl_pagesize))); |
f65fd747 | 2140 | |
fa8d436c | 2141 | /* A contiguous main_arena is consistent with sbrk_base. */ |
6c8dbf00 OB |
2142 | if (av == &main_arena && contiguous (av)) |
2143 | assert ((char *) mp_.sbrk_base + av->system_mem == | |
2144 | (char *) av->top + chunksize (av->top)); | |
fa8d436c UD |
2145 | |
2146 | /* properties of fastbins */ | |
2147 | ||
2148 | /* max_fast is in allowed range */ | |
6c8dbf00 OB |
2149 | assert ((get_max_fast () & ~1) <= request2size (MAX_FAST_SIZE)); |
2150 | ||
2151 | max_fast_bin = fastbin_index (get_max_fast ()); | |
2152 | ||
2153 | for (i = 0; i < NFASTBINS; ++i) | |
2154 | { | |
2155 | p = fastbin (av, i); | |
2156 | ||
2157 | /* The following test can only be performed for the main arena. | |
2158 | While mallopt calls malloc_consolidate to get rid of all fast | |
2159 | bins (especially those larger than the new maximum) this does | |
2160 | only happen for the main arena. Trying to do this for any | |
2161 | other arena would mean those arenas have to be locked and | |
2162 | malloc_consolidate be called for them. This is excessive. And | |
2163 | even if this is acceptable to somebody it still cannot solve | |
2164 | the problem completely since if the arena is locked a | |
2165 | concurrent malloc call might create a new arena which then | |
2166 | could use the newly invalid fast bins. */ | |
2167 | ||
2168 | /* all bins past max_fast are empty */ | |
2169 | if (av == &main_arena && i > max_fast_bin) | |
2170 | assert (p == 0); | |
2171 | ||
2172 | while (p != 0) | |
2173 | { | |
2174 | /* each chunk claims to be inuse */ | |
2175 | do_check_inuse_chunk (av, p); | |
2176 | total += chunksize (p); | |
2177 | /* chunk belongs in this bin */ | |
2178 | assert (fastbin_index (chunksize (p)) == i); | |
2179 | p = p->fd; | |
2180 | } | |
fa8d436c | 2181 | } |
fa8d436c | 2182 | |
fa8d436c | 2183 | /* check normal bins */ |
6c8dbf00 OB |
2184 | for (i = 1; i < NBINS; ++i) |
2185 | { | |
2186 | b = bin_at (av, i); | |
2187 | ||
2188 | /* binmap is accurate (except for bin 1 == unsorted_chunks) */ | |
2189 | if (i >= 2) | |
2190 | { | |
2191 | unsigned int binbit = get_binmap (av, i); | |
2192 | int empty = last (b) == b; | |
2193 | if (!binbit) | |
2194 | assert (empty); | |
2195 | else if (!empty) | |
2196 | assert (binbit); | |
2197 | } | |
2198 | ||
2199 | for (p = last (b); p != b; p = p->bk) | |
2200 | { | |
2201 | /* each chunk claims to be free */ | |
2202 | do_check_free_chunk (av, p); | |
2203 | size = chunksize (p); | |
2204 | total += size; | |
2205 | if (i >= 2) | |
2206 | { | |
2207 | /* chunk belongs in bin */ | |
2208 | idx = bin_index (size); | |
2209 | assert (idx == i); | |
2210 | /* lists are sorted */ | |
2211 | assert (p->bk == b || | |
2212 | (unsigned long) chunksize (p->bk) >= (unsigned long) chunksize (p)); | |
2213 | ||
2214 | if (!in_smallbin_range (size)) | |
2215 | { | |
2216 | if (p->fd_nextsize != NULL) | |
2217 | { | |
2218 | if (p->fd_nextsize == p) | |
2219 | assert (p->bk_nextsize == p); | |
2220 | else | |
2221 | { | |
2222 | if (p->fd_nextsize == first (b)) | |
2223 | assert (chunksize (p) < chunksize (p->fd_nextsize)); | |
2224 | else | |
2225 | assert (chunksize (p) > chunksize (p->fd_nextsize)); | |
2226 | ||
2227 | if (p == first (b)) | |
2228 | assert (chunksize (p) > chunksize (p->bk_nextsize)); | |
2229 | else | |
2230 | assert (chunksize (p) < chunksize (p->bk_nextsize)); | |
2231 | } | |
2232 | } | |
2233 | else | |
2234 | assert (p->bk_nextsize == NULL); | |
2235 | } | |
2236 | } | |
2237 | else if (!in_smallbin_range (size)) | |
2238 | assert (p->fd_nextsize == NULL && p->bk_nextsize == NULL); | |
2239 | /* chunk is followed by a legal chain of inuse chunks */ | |
2240 | for (q = next_chunk (p); | |
2241 | (q != av->top && inuse (q) && | |
2242 | (unsigned long) (chunksize (q)) >= MINSIZE); | |
2243 | q = next_chunk (q)) | |
2244 | do_check_inuse_chunk (av, q); | |
2245 | } | |
fa8d436c | 2246 | } |
f65fd747 | 2247 | |
fa8d436c | 2248 | /* top chunk is OK */ |
6c8dbf00 | 2249 | check_chunk (av, av->top); |
fa8d436c UD |
2250 | } |
2251 | #endif | |
2252 | ||
2253 | ||
2254 | /* ----------------- Support for debugging hooks -------------------- */ | |
2255 | #include "hooks.c" | |
2256 | ||
2257 | ||
2258 | /* ----------- Routines dealing with system allocation -------------- */ | |
2259 | ||
2260 | /* | |
6c8dbf00 OB |
2261 | sysmalloc handles malloc cases requiring more memory from the system. |
2262 | On entry, it is assumed that av->top does not have enough | |
2263 | space to service request for nb bytes, thus requiring that av->top | |
2264 | be extended or replaced. | |
2265 | */ | |
fa8d436c | 2266 | |
6c8dbf00 OB |
2267 | static void * |
2268 | sysmalloc (INTERNAL_SIZE_T nb, mstate av) | |
f65fd747 | 2269 | { |
6c8dbf00 | 2270 | mchunkptr old_top; /* incoming value of av->top */ |
fa8d436c | 2271 | INTERNAL_SIZE_T old_size; /* its size */ |
6c8dbf00 | 2272 | char *old_end; /* its end address */ |
f65fd747 | 2273 | |
6c8dbf00 OB |
2274 | long size; /* arg to first MORECORE or mmap call */ |
2275 | char *brk; /* return value from MORECORE */ | |
f65fd747 | 2276 | |
6c8dbf00 OB |
2277 | long correction; /* arg to 2nd MORECORE call */ |
2278 | char *snd_brk; /* 2nd return val */ | |
f65fd747 | 2279 | |
fa8d436c UD |
2280 | INTERNAL_SIZE_T front_misalign; /* unusable bytes at front of new space */ |
2281 | INTERNAL_SIZE_T end_misalign; /* partial page left at end of new space */ | |
6c8dbf00 | 2282 | char *aligned_brk; /* aligned offset into brk */ |
f65fd747 | 2283 | |
6c8dbf00 OB |
2284 | mchunkptr p; /* the allocated/returned chunk */ |
2285 | mchunkptr remainder; /* remainder from allocation */ | |
2286 | unsigned long remainder_size; /* its size */ | |
fa8d436c | 2287 | |
fa8d436c | 2288 | |
8a35c3fe | 2289 | size_t pagesize = GLRO (dl_pagesize); |
6c8dbf00 | 2290 | bool tried_mmap = false; |
fa8d436c UD |
2291 | |
2292 | ||
fa8d436c | 2293 | /* |
6c8dbf00 OB |
2294 | If have mmap, and the request size meets the mmap threshold, and |
2295 | the system supports mmap, and there are few enough currently | |
2296 | allocated mmapped regions, try to directly map this request | |
2297 | rather than expanding top. | |
2298 | */ | |
2299 | ||
fff94fa2 SP |
2300 | if (av == NULL |
2301 | || ((unsigned long) (nb) >= (unsigned long) (mp_.mmap_threshold) | |
2302 | && (mp_.n_mmaps < mp_.n_mmaps_max))) | |
6c8dbf00 OB |
2303 | { |
2304 | char *mm; /* return value from mmap call*/ | |
a9177ff5 | 2305 | |
6c8dbf00 OB |
2306 | try_mmap: |
2307 | /* | |
2308 | Round up size to nearest page. For mmapped chunks, the overhead | |
2309 | is one SIZE_SZ unit larger than for normal chunks, because there | |
2310 | is no following chunk whose prev_size field could be used. | |
2311 | ||
2312 | See the front_misalign handling below, for glibc there is no | |
2313 | need for further alignments unless we have have high alignment. | |
2314 | */ | |
2315 | if (MALLOC_ALIGNMENT == 2 * SIZE_SZ) | |
8a35c3fe | 2316 | size = ALIGN_UP (nb + SIZE_SZ, pagesize); |
6c8dbf00 | 2317 | else |
8a35c3fe | 2318 | size = ALIGN_UP (nb + SIZE_SZ + MALLOC_ALIGN_MASK, pagesize); |
6c8dbf00 OB |
2319 | tried_mmap = true; |
2320 | ||
2321 | /* Don't try if size wraps around 0 */ | |
2322 | if ((unsigned long) (size) > (unsigned long) (nb)) | |
2323 | { | |
2324 | mm = (char *) (MMAP (0, size, PROT_READ | PROT_WRITE, 0)); | |
2325 | ||
2326 | if (mm != MAP_FAILED) | |
2327 | { | |
2328 | /* | |
2329 | The offset to the start of the mmapped region is stored | |
2330 | in the prev_size field of the chunk. This allows us to adjust | |
2331 | returned start address to meet alignment requirements here | |
2332 | and in memalign(), and still be able to compute proper | |
2333 | address argument for later munmap in free() and realloc(). | |
2334 | */ | |
2335 | ||
2336 | if (MALLOC_ALIGNMENT == 2 * SIZE_SZ) | |
2337 | { | |
2338 | /* For glibc, chunk2mem increases the address by 2*SIZE_SZ and | |
2339 | MALLOC_ALIGN_MASK is 2*SIZE_SZ-1. Each mmap'ed area is page | |
2340 | aligned and therefore definitely MALLOC_ALIGN_MASK-aligned. */ | |
2341 | assert (((INTERNAL_SIZE_T) chunk2mem (mm) & MALLOC_ALIGN_MASK) == 0); | |
2342 | front_misalign = 0; | |
2343 | } | |
2344 | else | |
2345 | front_misalign = (INTERNAL_SIZE_T) chunk2mem (mm) & MALLOC_ALIGN_MASK; | |
2346 | if (front_misalign > 0) | |
2347 | { | |
2348 | correction = MALLOC_ALIGNMENT - front_misalign; | |
2349 | p = (mchunkptr) (mm + correction); | |
e9c4fe93 | 2350 | set_prev_size (p, correction); |
6c8dbf00 OB |
2351 | set_head (p, (size - correction) | IS_MMAPPED); |
2352 | } | |
2353 | else | |
2354 | { | |
2355 | p = (mchunkptr) mm; | |
681421f3 | 2356 | set_prev_size (p, 0); |
6c8dbf00 OB |
2357 | set_head (p, size | IS_MMAPPED); |
2358 | } | |
2359 | ||
2360 | /* update statistics */ | |
2361 | ||
2362 | int new = atomic_exchange_and_add (&mp_.n_mmaps, 1) + 1; | |
2363 | atomic_max (&mp_.max_n_mmaps, new); | |
2364 | ||
2365 | unsigned long sum; | |
2366 | sum = atomic_exchange_and_add (&mp_.mmapped_mem, size) + size; | |
2367 | atomic_max (&mp_.max_mmapped_mem, sum); | |
2368 | ||
2369 | check_chunk (av, p); | |
2370 | ||
2371 | return chunk2mem (p); | |
2372 | } | |
2373 | } | |
fa8d436c | 2374 | } |
fa8d436c | 2375 | |
fff94fa2 SP |
2376 | /* There are no usable arenas and mmap also failed. */ |
2377 | if (av == NULL) | |
2378 | return 0; | |
2379 | ||
fa8d436c UD |
2380 | /* Record incoming configuration of top */ |
2381 | ||
6c8dbf00 OB |
2382 | old_top = av->top; |
2383 | old_size = chunksize (old_top); | |
2384 | old_end = (char *) (chunk_at_offset (old_top, old_size)); | |
fa8d436c | 2385 | |
6c8dbf00 | 2386 | brk = snd_brk = (char *) (MORECORE_FAILURE); |
fa8d436c | 2387 | |
a9177ff5 | 2388 | /* |
fa8d436c UD |
2389 | If not the first time through, we require old_size to be |
2390 | at least MINSIZE and to have prev_inuse set. | |
6c8dbf00 | 2391 | */ |
fa8d436c | 2392 | |
6c8dbf00 OB |
2393 | assert ((old_top == initial_top (av) && old_size == 0) || |
2394 | ((unsigned long) (old_size) >= MINSIZE && | |
2395 | prev_inuse (old_top) && | |
8a35c3fe | 2396 | ((unsigned long) old_end & (pagesize - 1)) == 0)); |
fa8d436c UD |
2397 | |
2398 | /* Precondition: not enough current space to satisfy nb request */ | |
6c8dbf00 | 2399 | assert ((unsigned long) (old_size) < (unsigned long) (nb + MINSIZE)); |
a9177ff5 | 2400 | |
72f90263 | 2401 | |
6c8dbf00 OB |
2402 | if (av != &main_arena) |
2403 | { | |
2404 | heap_info *old_heap, *heap; | |
2405 | size_t old_heap_size; | |
2406 | ||
2407 | /* First try to extend the current heap. */ | |
2408 | old_heap = heap_for_ptr (old_top); | |
2409 | old_heap_size = old_heap->size; | |
2410 | if ((long) (MINSIZE + nb - old_size) > 0 | |
2411 | && grow_heap (old_heap, MINSIZE + nb - old_size) == 0) | |
2412 | { | |
2413 | av->system_mem += old_heap->size - old_heap_size; | |
6c8dbf00 OB |
2414 | set_head (old_top, (((char *) old_heap + old_heap->size) - (char *) old_top) |
2415 | | PREV_INUSE); | |
2416 | } | |
2417 | else if ((heap = new_heap (nb + (MINSIZE + sizeof (*heap)), mp_.top_pad))) | |
2418 | { | |
2419 | /* Use a newly allocated heap. */ | |
2420 | heap->ar_ptr = av; | |
2421 | heap->prev = old_heap; | |
2422 | av->system_mem += heap->size; | |
6c8dbf00 OB |
2423 | /* Set up the new top. */ |
2424 | top (av) = chunk_at_offset (heap, sizeof (*heap)); | |
2425 | set_head (top (av), (heap->size - sizeof (*heap)) | PREV_INUSE); | |
2426 | ||
2427 | /* Setup fencepost and free the old top chunk with a multiple of | |
2428 | MALLOC_ALIGNMENT in size. */ | |
2429 | /* The fencepost takes at least MINSIZE bytes, because it might | |
2430 | become the top chunk again later. Note that a footer is set | |
2431 | up, too, although the chunk is marked in use. */ | |
2432 | old_size = (old_size - MINSIZE) & ~MALLOC_ALIGN_MASK; | |
2433 | set_head (chunk_at_offset (old_top, old_size + 2 * SIZE_SZ), 0 | PREV_INUSE); | |
2434 | if (old_size >= MINSIZE) | |
2435 | { | |
2436 | set_head (chunk_at_offset (old_top, old_size), (2 * SIZE_SZ) | PREV_INUSE); | |
2437 | set_foot (chunk_at_offset (old_top, old_size), (2 * SIZE_SZ)); | |
2438 | set_head (old_top, old_size | PREV_INUSE | NON_MAIN_ARENA); | |
2439 | _int_free (av, old_top, 1); | |
2440 | } | |
2441 | else | |
2442 | { | |
2443 | set_head (old_top, (old_size + 2 * SIZE_SZ) | PREV_INUSE); | |
2444 | set_foot (old_top, (old_size + 2 * SIZE_SZ)); | |
2445 | } | |
2446 | } | |
2447 | else if (!tried_mmap) | |
2448 | /* We can at least try to use to mmap memory. */ | |
2449 | goto try_mmap; | |
fa8d436c | 2450 | } |
6c8dbf00 | 2451 | else /* av == main_arena */ |
fa8d436c | 2452 | |
fa8d436c | 2453 | |
6c8dbf00 OB |
2454 | { /* Request enough space for nb + pad + overhead */ |
2455 | size = nb + mp_.top_pad + MINSIZE; | |
a9177ff5 | 2456 | |
6c8dbf00 OB |
2457 | /* |
2458 | If contiguous, we can subtract out existing space that we hope to | |
2459 | combine with new space. We add it back later only if | |
2460 | we don't actually get contiguous space. | |
2461 | */ | |
a9177ff5 | 2462 | |
6c8dbf00 OB |
2463 | if (contiguous (av)) |
2464 | size -= old_size; | |
fa8d436c | 2465 | |
6c8dbf00 OB |
2466 | /* |
2467 | Round to a multiple of page size. | |
2468 | If MORECORE is not contiguous, this ensures that we only call it | |
2469 | with whole-page arguments. And if MORECORE is contiguous and | |
2470 | this is not first time through, this preserves page-alignment of | |
2471 | previous calls. Otherwise, we correct to page-align below. | |
2472 | */ | |
fa8d436c | 2473 | |
8a35c3fe | 2474 | size = ALIGN_UP (size, pagesize); |
fa8d436c | 2475 | |
6c8dbf00 OB |
2476 | /* |
2477 | Don't try to call MORECORE if argument is so big as to appear | |
2478 | negative. Note that since mmap takes size_t arg, it may succeed | |
2479 | below even if we cannot call MORECORE. | |
2480 | */ | |
2481 | ||
2482 | if (size > 0) | |
2483 | { | |
2484 | brk = (char *) (MORECORE (size)); | |
2485 | LIBC_PROBE (memory_sbrk_more, 2, brk, size); | |
2486 | } | |
2487 | ||
2488 | if (brk != (char *) (MORECORE_FAILURE)) | |
2489 | { | |
2490 | /* Call the `morecore' hook if necessary. */ | |
2491 | void (*hook) (void) = atomic_forced_read (__after_morecore_hook); | |
2492 | if (__builtin_expect (hook != NULL, 0)) | |
2493 | (*hook)(); | |
2494 | } | |
2495 | else | |
2496 | { | |
2497 | /* | |
2498 | If have mmap, try using it as a backup when MORECORE fails or | |
2499 | cannot be used. This is worth doing on systems that have "holes" in | |
2500 | address space, so sbrk cannot extend to give contiguous space, but | |
2501 | space is available elsewhere. Note that we ignore mmap max count | |
2502 | and threshold limits, since the space will not be used as a | |
2503 | segregated mmap region. | |
2504 | */ | |
2505 | ||
2506 | /* Cannot merge with old top, so add its size back in */ | |
2507 | if (contiguous (av)) | |
8a35c3fe | 2508 | size = ALIGN_UP (size + old_size, pagesize); |
6c8dbf00 OB |
2509 | |
2510 | /* If we are relying on mmap as backup, then use larger units */ | |
2511 | if ((unsigned long) (size) < (unsigned long) (MMAP_AS_MORECORE_SIZE)) | |
2512 | size = MMAP_AS_MORECORE_SIZE; | |
2513 | ||
2514 | /* Don't try if size wraps around 0 */ | |
2515 | if ((unsigned long) (size) > (unsigned long) (nb)) | |
2516 | { | |
2517 | char *mbrk = (char *) (MMAP (0, size, PROT_READ | PROT_WRITE, 0)); | |
2518 | ||
2519 | if (mbrk != MAP_FAILED) | |
2520 | { | |
2521 | /* We do not need, and cannot use, another sbrk call to find end */ | |
2522 | brk = mbrk; | |
2523 | snd_brk = brk + size; | |
2524 | ||
2525 | /* | |
2526 | Record that we no longer have a contiguous sbrk region. | |
2527 | After the first time mmap is used as backup, we do not | |
2528 | ever rely on contiguous space since this could incorrectly | |
2529 | bridge regions. | |
2530 | */ | |
2531 | set_noncontiguous (av); | |
2532 | } | |
2533 | } | |
2534 | } | |
2535 | ||
2536 | if (brk != (char *) (MORECORE_FAILURE)) | |
2537 | { | |
2538 | if (mp_.sbrk_base == 0) | |
2539 | mp_.sbrk_base = brk; | |
2540 | av->system_mem += size; | |
2541 | ||
2542 | /* | |
2543 | If MORECORE extends previous space, we can likewise extend top size. | |
2544 | */ | |
2545 | ||
2546 | if (brk == old_end && snd_brk == (char *) (MORECORE_FAILURE)) | |
2547 | set_head (old_top, (size + old_size) | PREV_INUSE); | |
2548 | ||
2549 | else if (contiguous (av) && old_size && brk < old_end) | |
ac3ed168 FW |
2550 | /* Oops! Someone else killed our space.. Can't touch anything. */ |
2551 | malloc_printerr ("break adjusted to free malloc space"); | |
6c8dbf00 OB |
2552 | |
2553 | /* | |
2554 | Otherwise, make adjustments: | |
2555 | ||
2556 | * If the first time through or noncontiguous, we need to call sbrk | |
2557 | just to find out where the end of memory lies. | |
2558 | ||
2559 | * We need to ensure that all returned chunks from malloc will meet | |
2560 | MALLOC_ALIGNMENT | |
2561 | ||
2562 | * If there was an intervening foreign sbrk, we need to adjust sbrk | |
2563 | request size to account for fact that we will not be able to | |
2564 | combine new space with existing space in old_top. | |
2565 | ||
2566 | * Almost all systems internally allocate whole pages at a time, in | |
2567 | which case we might as well use the whole last page of request. | |
2568 | So we allocate enough more memory to hit a page boundary now, | |
2569 | which in turn causes future contiguous calls to page-align. | |
2570 | */ | |
2571 | ||
2572 | else | |
2573 | { | |
2574 | front_misalign = 0; | |
2575 | end_misalign = 0; | |
2576 | correction = 0; | |
2577 | aligned_brk = brk; | |
2578 | ||
2579 | /* handle contiguous cases */ | |
2580 | if (contiguous (av)) | |
2581 | { | |
2582 | /* Count foreign sbrk as system_mem. */ | |
2583 | if (old_size) | |
2584 | av->system_mem += brk - old_end; | |
2585 | ||
2586 | /* Guarantee alignment of first new chunk made from this space */ | |
2587 | ||
2588 | front_misalign = (INTERNAL_SIZE_T) chunk2mem (brk) & MALLOC_ALIGN_MASK; | |
2589 | if (front_misalign > 0) | |
2590 | { | |
2591 | /* | |
2592 | Skip over some bytes to arrive at an aligned position. | |
2593 | We don't need to specially mark these wasted front bytes. | |
2594 | They will never be accessed anyway because | |
2595 | prev_inuse of av->top (and any chunk created from its start) | |
2596 | is always true after initialization. | |
2597 | */ | |
2598 | ||
2599 | correction = MALLOC_ALIGNMENT - front_misalign; | |
2600 | aligned_brk += correction; | |
2601 | } | |
2602 | ||
2603 | /* | |
2604 | If this isn't adjacent to existing space, then we will not | |
2605 | be able to merge with old_top space, so must add to 2nd request. | |
2606 | */ | |
2607 | ||
2608 | correction += old_size; | |
2609 | ||
2610 | /* Extend the end address to hit a page boundary */ | |
2611 | end_misalign = (INTERNAL_SIZE_T) (brk + size + correction); | |
8a35c3fe | 2612 | correction += (ALIGN_UP (end_misalign, pagesize)) - end_misalign; |
6c8dbf00 OB |
2613 | |
2614 | assert (correction >= 0); | |
2615 | snd_brk = (char *) (MORECORE (correction)); | |
2616 | ||
2617 | /* | |
2618 | If can't allocate correction, try to at least find out current | |
2619 | brk. It might be enough to proceed without failing. | |
2620 | ||
2621 | Note that if second sbrk did NOT fail, we assume that space | |
2622 | is contiguous with first sbrk. This is a safe assumption unless | |
2623 | program is multithreaded but doesn't use locks and a foreign sbrk | |
2624 | occurred between our first and second calls. | |
2625 | */ | |
2626 | ||
2627 | if (snd_brk == (char *) (MORECORE_FAILURE)) | |
2628 | { | |
2629 | correction = 0; | |
2630 | snd_brk = (char *) (MORECORE (0)); | |
2631 | } | |
2632 | else | |
2633 | { | |
2634 | /* Call the `morecore' hook if necessary. */ | |
2635 | void (*hook) (void) = atomic_forced_read (__after_morecore_hook); | |
2636 | if (__builtin_expect (hook != NULL, 0)) | |
2637 | (*hook)(); | |
2638 | } | |
2639 | } | |
2640 | ||
2641 | /* handle non-contiguous cases */ | |
2642 | else | |
2643 | { | |
2644 | if (MALLOC_ALIGNMENT == 2 * SIZE_SZ) | |
2645 | /* MORECORE/mmap must correctly align */ | |
2646 | assert (((unsigned long) chunk2mem (brk) & MALLOC_ALIGN_MASK) == 0); | |
2647 | else | |
2648 | { | |
2649 | front_misalign = (INTERNAL_SIZE_T) chunk2mem (brk) & MALLOC_ALIGN_MASK; | |
2650 | if (front_misalign > 0) | |
2651 | { | |
2652 | /* | |
2653 | Skip over some bytes to arrive at an aligned position. | |
2654 | We don't need to specially mark these wasted front bytes. | |
2655 | They will never be accessed anyway because | |
2656 | prev_inuse of av->top (and any chunk created from its start) | |
2657 | is always true after initialization. | |
2658 | */ | |
2659 | ||
2660 | aligned_brk += MALLOC_ALIGNMENT - front_misalign; | |
2661 | } | |
2662 | } | |
2663 | ||
2664 | /* Find out current end of memory */ | |
2665 | if (snd_brk == (char *) (MORECORE_FAILURE)) | |
2666 | { | |
2667 | snd_brk = (char *) (MORECORE (0)); | |
2668 | } | |
2669 | } | |
2670 | ||
2671 | /* Adjust top based on results of second sbrk */ | |
2672 | if (snd_brk != (char *) (MORECORE_FAILURE)) | |
2673 | { | |
2674 | av->top = (mchunkptr) aligned_brk; | |
2675 | set_head (av->top, (snd_brk - aligned_brk + correction) | PREV_INUSE); | |
2676 | av->system_mem += correction; | |
2677 | ||
2678 | /* | |
2679 | If not the first time through, we either have a | |
2680 | gap due to foreign sbrk or a non-contiguous region. Insert a | |
2681 | double fencepost at old_top to prevent consolidation with space | |
2682 | we don't own. These fenceposts are artificial chunks that are | |
2683 | marked as inuse and are in any case too small to use. We need | |
2684 | two to make sizes and alignments work out. | |
2685 | */ | |
2686 | ||
2687 | if (old_size != 0) | |
2688 | { | |
2689 | /* | |
2690 | Shrink old_top to insert fenceposts, keeping size a | |
2691 | multiple of MALLOC_ALIGNMENT. We know there is at least | |
2692 | enough space in old_top to do this. | |
2693 | */ | |
2694 | old_size = (old_size - 4 * SIZE_SZ) & ~MALLOC_ALIGN_MASK; | |
2695 | set_head (old_top, old_size | PREV_INUSE); | |
2696 | ||
2697 | /* | |
2698 | Note that the following assignments completely overwrite | |
2699 | old_top when old_size was previously MINSIZE. This is | |
2700 | intentional. We need the fencepost, even if old_top otherwise gets | |
2701 | lost. | |
2702 | */ | |
e9c4fe93 FW |
2703 | set_head (chunk_at_offset (old_top, old_size), |
2704 | (2 * SIZE_SZ) | PREV_INUSE); | |
2705 | set_head (chunk_at_offset (old_top, old_size + 2 * SIZE_SZ), | |
2706 | (2 * SIZE_SZ) | PREV_INUSE); | |
6c8dbf00 OB |
2707 | |
2708 | /* If possible, release the rest. */ | |
2709 | if (old_size >= MINSIZE) | |
2710 | { | |
2711 | _int_free (av, old_top, 1); | |
2712 | } | |
2713 | } | |
2714 | } | |
2715 | } | |
2716 | } | |
2717 | } /* if (av != &main_arena) */ | |
2718 | ||
2719 | if ((unsigned long) av->system_mem > (unsigned long) (av->max_system_mem)) | |
fa8d436c | 2720 | av->max_system_mem = av->system_mem; |
6c8dbf00 | 2721 | check_malloc_state (av); |
a9177ff5 | 2722 | |
fa8d436c UD |
2723 | /* finally, do the allocation */ |
2724 | p = av->top; | |
6c8dbf00 | 2725 | size = chunksize (p); |
fa8d436c UD |
2726 | |
2727 | /* check that one of the above allocation paths succeeded */ | |
6c8dbf00 OB |
2728 | if ((unsigned long) (size) >= (unsigned long) (nb + MINSIZE)) |
2729 | { | |
2730 | remainder_size = size - nb; | |
2731 | remainder = chunk_at_offset (p, nb); | |
2732 | av->top = remainder; | |
2733 | set_head (p, nb | PREV_INUSE | (av != &main_arena ? NON_MAIN_ARENA : 0)); | |
2734 | set_head (remainder, remainder_size | PREV_INUSE); | |
2735 | check_malloced_chunk (av, p, nb); | |
2736 | return chunk2mem (p); | |
2737 | } | |
fa8d436c UD |
2738 | |
2739 | /* catch all failure paths */ | |
8e58439c | 2740 | __set_errno (ENOMEM); |
fa8d436c UD |
2741 | return 0; |
2742 | } | |
2743 | ||
2744 | ||
2745 | /* | |
6c8dbf00 OB |
2746 | systrim is an inverse of sorts to sysmalloc. It gives memory back |
2747 | to the system (via negative arguments to sbrk) if there is unused | |
2748 | memory at the `high' end of the malloc pool. It is called | |
2749 | automatically by free() when top space exceeds the trim | |
2750 | threshold. It is also called by the public malloc_trim routine. It | |
2751 | returns 1 if it actually released any memory, else 0. | |
2752 | */ | |
fa8d436c | 2753 | |
6c8dbf00 OB |
2754 | static int |
2755 | systrim (size_t pad, mstate av) | |
fa8d436c | 2756 | { |
6c8dbf00 OB |
2757 | long top_size; /* Amount of top-most memory */ |
2758 | long extra; /* Amount to release */ | |
2759 | long released; /* Amount actually released */ | |
2760 | char *current_brk; /* address returned by pre-check sbrk call */ | |
2761 | char *new_brk; /* address returned by post-check sbrk call */ | |
8a35c3fe | 2762 | size_t pagesize; |
6c8dbf00 | 2763 | long top_area; |
fa8d436c | 2764 | |
8a35c3fe | 2765 | pagesize = GLRO (dl_pagesize); |
6c8dbf00 | 2766 | top_size = chunksize (av->top); |
a9177ff5 | 2767 | |
4b5b548c FS |
2768 | top_area = top_size - MINSIZE - 1; |
2769 | if (top_area <= pad) | |
2770 | return 0; | |
2771 | ||
ca6be165 CD |
2772 | /* Release in pagesize units and round down to the nearest page. */ |
2773 | extra = ALIGN_DOWN(top_area - pad, pagesize); | |
a9177ff5 | 2774 | |
51a7380b WN |
2775 | if (extra == 0) |
2776 | return 0; | |
2777 | ||
4b5b548c | 2778 | /* |
6c8dbf00 OB |
2779 | Only proceed if end of memory is where we last set it. |
2780 | This avoids problems if there were foreign sbrk calls. | |
2781 | */ | |
2782 | current_brk = (char *) (MORECORE (0)); | |
2783 | if (current_brk == (char *) (av->top) + top_size) | |
2784 | { | |
2785 | /* | |
2786 | Attempt to release memory. We ignore MORECORE return value, | |
2787 | and instead call again to find out where new end of memory is. | |
2788 | This avoids problems if first call releases less than we asked, | |
2789 | of if failure somehow altered brk value. (We could still | |
2790 | encounter problems if it altered brk in some very bad way, | |
2791 | but the only thing we can do is adjust anyway, which will cause | |
2792 | some downstream failure.) | |
2793 | */ | |
2794 | ||
2795 | MORECORE (-extra); | |
2796 | /* Call the `morecore' hook if necessary. */ | |
2797 | void (*hook) (void) = atomic_forced_read (__after_morecore_hook); | |
2798 | if (__builtin_expect (hook != NULL, 0)) | |
2799 | (*hook)(); | |
2800 | new_brk = (char *) (MORECORE (0)); | |
2801 | ||
2802 | LIBC_PROBE (memory_sbrk_less, 2, new_brk, extra); | |
2803 | ||
2804 | if (new_brk != (char *) MORECORE_FAILURE) | |
2805 | { | |
2806 | released = (long) (current_brk - new_brk); | |
2807 | ||
2808 | if (released != 0) | |
2809 | { | |
2810 | /* Success. Adjust top. */ | |
2811 | av->system_mem -= released; | |
2812 | set_head (av->top, (top_size - released) | PREV_INUSE); | |
2813 | check_malloc_state (av); | |
2814 | return 1; | |
2815 | } | |
2816 | } | |
fa8d436c | 2817 | } |
fa8d436c | 2818 | return 0; |
f65fd747 UD |
2819 | } |
2820 | ||
431c33c0 | 2821 | static void |
6c8dbf00 | 2822 | munmap_chunk (mchunkptr p) |
f65fd747 | 2823 | { |
c0e82f11 | 2824 | size_t pagesize = GLRO (dl_pagesize); |
6c8dbf00 | 2825 | INTERNAL_SIZE_T size = chunksize (p); |
f65fd747 | 2826 | |
6c8dbf00 | 2827 | assert (chunk_is_mmapped (p)); |
8e635611 | 2828 | |
4cf6c72f FW |
2829 | /* Do nothing if the chunk is a faked mmapped chunk in the dumped |
2830 | main arena. We never free this memory. */ | |
2831 | if (DUMPED_MAIN_ARENA_CHUNK (p)) | |
2832 | return; | |
2833 | ||
c0e82f11 | 2834 | uintptr_t mem = (uintptr_t) chunk2mem (p); |
e9c4fe93 FW |
2835 | uintptr_t block = (uintptr_t) p - prev_size (p); |
2836 | size_t total_size = prev_size (p) + size; | |
8e635611 UD |
2837 | /* Unfortunately we have to do the compilers job by hand here. Normally |
2838 | we would test BLOCK and TOTAL-SIZE separately for compliance with the | |
2839 | page size. But gcc does not recognize the optimization possibility | |
2840 | (in the moment at least) so we combine the two values into one before | |
2841 | the bit test. */ | |
c0e82f11 IK |
2842 | if (__glibc_unlikely ((block | total_size) & (pagesize - 1)) != 0 |
2843 | || __glibc_unlikely (!powerof2 (mem & (pagesize - 1)))) | |
ac3ed168 | 2844 | malloc_printerr ("munmap_chunk(): invalid pointer"); |
f65fd747 | 2845 | |
c6e4925d OB |
2846 | atomic_decrement (&mp_.n_mmaps); |
2847 | atomic_add (&mp_.mmapped_mem, -total_size); | |
f65fd747 | 2848 | |
6ef76f3b UD |
2849 | /* If munmap failed the process virtual memory address space is in a |
2850 | bad shape. Just leave the block hanging around, the process will | |
2851 | terminate shortly anyway since not much can be done. */ | |
6c8dbf00 | 2852 | __munmap ((char *) block, total_size); |
f65fd747 UD |
2853 | } |
2854 | ||
2855 | #if HAVE_MREMAP | |
2856 | ||
431c33c0 | 2857 | static mchunkptr |
6c8dbf00 | 2858 | mremap_chunk (mchunkptr p, size_t new_size) |
f65fd747 | 2859 | { |
8a35c3fe | 2860 | size_t pagesize = GLRO (dl_pagesize); |
e9c4fe93 | 2861 | INTERNAL_SIZE_T offset = prev_size (p); |
6c8dbf00 | 2862 | INTERNAL_SIZE_T size = chunksize (p); |
f65fd747 UD |
2863 | char *cp; |
2864 | ||
6c8dbf00 | 2865 | assert (chunk_is_mmapped (p)); |
ebe544bf IK |
2866 | |
2867 | uintptr_t block = (uintptr_t) p - offset; | |
2868 | uintptr_t mem = (uintptr_t) chunk2mem(p); | |
2869 | size_t total_size = offset + size; | |
2870 | if (__glibc_unlikely ((block | total_size) & (pagesize - 1)) != 0 | |
2871 | || __glibc_unlikely (!powerof2 (mem & (pagesize - 1)))) | |
2872 | malloc_printerr("mremap_chunk(): invalid pointer"); | |
f65fd747 UD |
2873 | |
2874 | /* Note the extra SIZE_SZ overhead as in mmap_chunk(). */ | |
8a35c3fe | 2875 | new_size = ALIGN_UP (new_size + offset + SIZE_SZ, pagesize); |
f65fd747 | 2876 | |
68f3802d | 2877 | /* No need to remap if the number of pages does not change. */ |
ebe544bf | 2878 | if (total_size == new_size) |
68f3802d UD |
2879 | return p; |
2880 | ||
ebe544bf | 2881 | cp = (char *) __mremap ((char *) block, total_size, new_size, |
6c8dbf00 | 2882 | MREMAP_MAYMOVE); |
f65fd747 | 2883 | |
6c8dbf00 OB |
2884 | if (cp == MAP_FAILED) |
2885 | return 0; | |
f65fd747 | 2886 | |
6c8dbf00 | 2887 | p = (mchunkptr) (cp + offset); |
f65fd747 | 2888 | |
6c8dbf00 | 2889 | assert (aligned_OK (chunk2mem (p))); |
f65fd747 | 2890 | |
e9c4fe93 | 2891 | assert (prev_size (p) == offset); |
6c8dbf00 | 2892 | set_head (p, (new_size - offset) | IS_MMAPPED); |
f65fd747 | 2893 | |
c6e4925d OB |
2894 | INTERNAL_SIZE_T new; |
2895 | new = atomic_exchange_and_add (&mp_.mmapped_mem, new_size - size - offset) | |
6c8dbf00 | 2896 | + new_size - size - offset; |
c6e4925d | 2897 | atomic_max (&mp_.max_mmapped_mem, new); |
f65fd747 UD |
2898 | return p; |
2899 | } | |
f65fd747 UD |
2900 | #endif /* HAVE_MREMAP */ |
2901 | ||
fa8d436c | 2902 | /*------------------------ Public wrappers. --------------------------------*/ |
f65fd747 | 2903 | |
d5c3fafc DD |
2904 | #if USE_TCACHE |
2905 | ||
2906 | /* We overlay this structure on the user-data portion of a chunk when | |
2907 | the chunk is stored in the per-thread cache. */ | |
2908 | typedef struct tcache_entry | |
2909 | { | |
2910 | struct tcache_entry *next; | |
bcdaad21 DD |
2911 | /* This field exists to detect double frees. */ |
2912 | struct tcache_perthread_struct *key; | |
d5c3fafc DD |
2913 | } tcache_entry; |
2914 | ||
2915 | /* There is one of these for each thread, which contains the | |
2916 | per-thread cache (hence "tcache_perthread_struct"). Keeping | |
2917 | overall size low is mildly important. Note that COUNTS and ENTRIES | |
2918 | are redundant (we could have just counted the linked list each | |
2919 | time), this is for performance reasons. */ | |
2920 | typedef struct tcache_perthread_struct | |
2921 | { | |
0ad788fa | 2922 | uint16_t counts[TCACHE_MAX_BINS]; |
d5c3fafc DD |
2923 | tcache_entry *entries[TCACHE_MAX_BINS]; |
2924 | } tcache_perthread_struct; | |
2925 | ||
1e26d351 | 2926 | static __thread bool tcache_shutting_down = false; |
d5c3fafc DD |
2927 | static __thread tcache_perthread_struct *tcache = NULL; |
2928 | ||
2929 | /* Caller must ensure that we know tc_idx is valid and there's room | |
2930 | for more chunks. */ | |
e4dd4ace | 2931 | static __always_inline void |
d5c3fafc DD |
2932 | tcache_put (mchunkptr chunk, size_t tc_idx) |
2933 | { | |
2934 | tcache_entry *e = (tcache_entry *) chunk2mem (chunk); | |
bcdaad21 DD |
2935 | |
2936 | /* Mark this chunk as "in the tcache" so the test in _int_free will | |
2937 | detect a double free. */ | |
2938 | e->key = tcache; | |
2939 | ||
d5c3fafc DD |
2940 | e->next = tcache->entries[tc_idx]; |
2941 | tcache->entries[tc_idx] = e; | |
2942 | ++(tcache->counts[tc_idx]); | |
2943 | } | |
2944 | ||
2945 | /* Caller must ensure that we know tc_idx is valid and there's | |
2946 | available chunks to remove. */ | |
e4dd4ace | 2947 | static __always_inline void * |
d5c3fafc DD |
2948 | tcache_get (size_t tc_idx) |
2949 | { | |
2950 | tcache_entry *e = tcache->entries[tc_idx]; | |
d5c3fafc DD |
2951 | tcache->entries[tc_idx] = e->next; |
2952 | --(tcache->counts[tc_idx]); | |
bcdaad21 | 2953 | e->key = NULL; |
d5c3fafc DD |
2954 | return (void *) e; |
2955 | } | |
2956 | ||
0a947e06 FW |
2957 | static void |
2958 | tcache_thread_shutdown (void) | |
d5c3fafc DD |
2959 | { |
2960 | int i; | |
2961 | tcache_perthread_struct *tcache_tmp = tcache; | |
2962 | ||
2963 | if (!tcache) | |
2964 | return; | |
2965 | ||
1e26d351 | 2966 | /* Disable the tcache and prevent it from being reinitialized. */ |
d5c3fafc | 2967 | tcache = NULL; |
1e26d351 | 2968 | tcache_shutting_down = true; |
d5c3fafc | 2969 | |
1e26d351 CD |
2970 | /* Free all of the entries and the tcache itself back to the arena |
2971 | heap for coalescing. */ | |
d5c3fafc DD |
2972 | for (i = 0; i < TCACHE_MAX_BINS; ++i) |
2973 | { | |
2974 | while (tcache_tmp->entries[i]) | |
2975 | { | |
2976 | tcache_entry *e = tcache_tmp->entries[i]; | |
2977 | tcache_tmp->entries[i] = e->next; | |
2978 | __libc_free (e); | |
2979 | } | |
2980 | } | |
2981 | ||
2982 | __libc_free (tcache_tmp); | |
d5c3fafc | 2983 | } |
d5c3fafc DD |
2984 | |
2985 | static void | |
2986 | tcache_init(void) | |
2987 | { | |
2988 | mstate ar_ptr; | |
2989 | void *victim = 0; | |
2990 | const size_t bytes = sizeof (tcache_perthread_struct); | |
2991 | ||
2992 | if (tcache_shutting_down) | |
2993 | return; | |
2994 | ||
2995 | arena_get (ar_ptr, bytes); | |
2996 | victim = _int_malloc (ar_ptr, bytes); | |
2997 | if (!victim && ar_ptr != NULL) | |
2998 | { | |
2999 | ar_ptr = arena_get_retry (ar_ptr, bytes); | |
3000 | victim = _int_malloc (ar_ptr, bytes); | |
3001 | } | |
3002 | ||
3003 | ||
3004 | if (ar_ptr != NULL) | |
3005 | __libc_lock_unlock (ar_ptr->mutex); | |
3006 | ||
3007 | /* In a low memory situation, we may not be able to allocate memory | |
3008 | - in which case, we just keep trying later. However, we | |
3009 | typically do this very early, so either there is sufficient | |
3010 | memory, or there isn't enough memory to do non-trivial | |
3011 | allocations anyway. */ | |
3012 | if (victim) | |
3013 | { | |
3014 | tcache = (tcache_perthread_struct *) victim; | |
3015 | memset (tcache, 0, sizeof (tcache_perthread_struct)); | |
3016 | } | |
3017 | ||
3018 | } | |
3019 | ||
0a947e06 | 3020 | # define MAYBE_INIT_TCACHE() \ |
d5c3fafc DD |
3021 | if (__glibc_unlikely (tcache == NULL)) \ |
3022 | tcache_init(); | |
3023 | ||
0a947e06 FW |
3024 | #else /* !USE_TCACHE */ |
3025 | # define MAYBE_INIT_TCACHE() | |
3026 | ||
3027 | static void | |
3028 | tcache_thread_shutdown (void) | |
3029 | { | |
3030 | /* Nothing to do if there is no thread cache. */ | |
3031 | } | |
3032 | ||
3033 | #endif /* !USE_TCACHE */ | |
d5c3fafc | 3034 | |
6c8dbf00 OB |
3035 | void * |
3036 | __libc_malloc (size_t bytes) | |
fa8d436c UD |
3037 | { |
3038 | mstate ar_ptr; | |
22a89187 | 3039 | void *victim; |
f65fd747 | 3040 | |
a222d91a | 3041 | void *(*hook) (size_t, const void *) |
f3eeb3fc | 3042 | = atomic_forced_read (__malloc_hook); |
bfacf1af | 3043 | if (__builtin_expect (hook != NULL, 0)) |
fa8d436c | 3044 | return (*hook)(bytes, RETURN_ADDRESS (0)); |
d5c3fafc DD |
3045 | #if USE_TCACHE |
3046 | /* int_free also calls request2size, be careful to not pad twice. */ | |
34697694 AS |
3047 | size_t tbytes; |
3048 | checked_request2size (bytes, tbytes); | |
d5c3fafc DD |
3049 | size_t tc_idx = csize2tidx (tbytes); |
3050 | ||
3051 | MAYBE_INIT_TCACHE (); | |
3052 | ||
3053 | DIAG_PUSH_NEEDS_COMMENT; | |
3054 | if (tc_idx < mp_.tcache_bins | |
d5c3fafc | 3055 | && tcache |
0ad788fa | 3056 | && tcache->counts[tc_idx] > 0) |
d5c3fafc DD |
3057 | { |
3058 | return tcache_get (tc_idx); | |
3059 | } | |
3060 | DIAG_POP_NEEDS_COMMENT; | |
3061 | #endif | |
f65fd747 | 3062 | |
3f6bb8a3 WD |
3063 | if (SINGLE_THREAD_P) |
3064 | { | |
3065 | victim = _int_malloc (&main_arena, bytes); | |
3066 | assert (!victim || chunk_is_mmapped (mem2chunk (victim)) || | |
3067 | &main_arena == arena_for_chunk (mem2chunk (victim))); | |
3068 | return victim; | |
3069 | } | |
3070 | ||
94c5a52a | 3071 | arena_get (ar_ptr, bytes); |
425ce2ed | 3072 | |
6c8dbf00 | 3073 | victim = _int_malloc (ar_ptr, bytes); |
fff94fa2 SP |
3074 | /* Retry with another arena only if we were able to find a usable arena |
3075 | before. */ | |
3076 | if (!victim && ar_ptr != NULL) | |
6c8dbf00 OB |
3077 | { |
3078 | LIBC_PROBE (memory_malloc_retry, 1, bytes); | |
3079 | ar_ptr = arena_get_retry (ar_ptr, bytes); | |
fff94fa2 | 3080 | victim = _int_malloc (ar_ptr, bytes); |
60f0e64b | 3081 | } |
fff94fa2 SP |
3082 | |
3083 | if (ar_ptr != NULL) | |
4bf5f222 | 3084 | __libc_lock_unlock (ar_ptr->mutex); |
fff94fa2 | 3085 | |
6c8dbf00 OB |
3086 | assert (!victim || chunk_is_mmapped (mem2chunk (victim)) || |
3087 | ar_ptr == arena_for_chunk (mem2chunk (victim))); | |
fa8d436c | 3088 | return victim; |
f65fd747 | 3089 | } |
6c8dbf00 | 3090 | libc_hidden_def (__libc_malloc) |
f65fd747 | 3091 | |
fa8d436c | 3092 | void |
6c8dbf00 | 3093 | __libc_free (void *mem) |
f65fd747 | 3094 | { |
fa8d436c UD |
3095 | mstate ar_ptr; |
3096 | mchunkptr p; /* chunk corresponding to mem */ | |
3097 | ||
a222d91a | 3098 | void (*hook) (void *, const void *) |
f3eeb3fc | 3099 | = atomic_forced_read (__free_hook); |
6c8dbf00 OB |
3100 | if (__builtin_expect (hook != NULL, 0)) |
3101 | { | |
3102 | (*hook)(mem, RETURN_ADDRESS (0)); | |
3103 | return; | |
3104 | } | |
f65fd747 | 3105 | |
fa8d436c UD |
3106 | if (mem == 0) /* free(0) has no effect */ |
3107 | return; | |
f65fd747 | 3108 | |
6c8dbf00 | 3109 | p = mem2chunk (mem); |
f65fd747 | 3110 | |
6c8dbf00 OB |
3111 | if (chunk_is_mmapped (p)) /* release mmapped memory. */ |
3112 | { | |
4cf6c72f FW |
3113 | /* See if the dynamic brk/mmap threshold needs adjusting. |
3114 | Dumped fake mmapped chunks do not affect the threshold. */ | |
6c8dbf00 | 3115 | if (!mp_.no_dyn_threshold |
e9c4fe93 FW |
3116 | && chunksize_nomask (p) > mp_.mmap_threshold |
3117 | && chunksize_nomask (p) <= DEFAULT_MMAP_THRESHOLD_MAX | |
4cf6c72f | 3118 | && !DUMPED_MAIN_ARENA_CHUNK (p)) |
6c8dbf00 OB |
3119 | { |
3120 | mp_.mmap_threshold = chunksize (p); | |
3121 | mp_.trim_threshold = 2 * mp_.mmap_threshold; | |
3122 | LIBC_PROBE (memory_mallopt_free_dyn_thresholds, 2, | |
3123 | mp_.mmap_threshold, mp_.trim_threshold); | |
3124 | } | |
3125 | munmap_chunk (p); | |
3126 | return; | |
3127 | } | |
f65fd747 | 3128 | |
d5c3fafc DD |
3129 | MAYBE_INIT_TCACHE (); |
3130 | ||
6c8dbf00 OB |
3131 | ar_ptr = arena_for_chunk (p); |
3132 | _int_free (ar_ptr, p, 0); | |
f65fd747 | 3133 | } |
3b49edc0 | 3134 | libc_hidden_def (__libc_free) |
f65fd747 | 3135 | |
6c8dbf00 OB |
3136 | void * |
3137 | __libc_realloc (void *oldmem, size_t bytes) | |
f65fd747 | 3138 | { |
fa8d436c | 3139 | mstate ar_ptr; |
6c8dbf00 | 3140 | INTERNAL_SIZE_T nb; /* padded request size */ |
f65fd747 | 3141 | |
6c8dbf00 | 3142 | void *newp; /* chunk to return */ |
f65fd747 | 3143 | |
a222d91a | 3144 | void *(*hook) (void *, size_t, const void *) = |
f3eeb3fc | 3145 | atomic_forced_read (__realloc_hook); |
bfacf1af | 3146 | if (__builtin_expect (hook != NULL, 0)) |
fa8d436c | 3147 | return (*hook)(oldmem, bytes, RETURN_ADDRESS (0)); |
f65fd747 | 3148 | |
fa8d436c | 3149 | #if REALLOC_ZERO_BYTES_FREES |
6c8dbf00 OB |
3150 | if (bytes == 0 && oldmem != NULL) |
3151 | { | |
3152 | __libc_free (oldmem); return 0; | |
3153 | } | |
f65fd747 | 3154 | #endif |
f65fd747 | 3155 | |
fa8d436c | 3156 | /* realloc of null is supposed to be same as malloc */ |
6c8dbf00 OB |
3157 | if (oldmem == 0) |
3158 | return __libc_malloc (bytes); | |
f65fd747 | 3159 | |
78ac92ad | 3160 | /* chunk corresponding to oldmem */ |
6c8dbf00 | 3161 | const mchunkptr oldp = mem2chunk (oldmem); |
78ac92ad | 3162 | /* its size */ |
6c8dbf00 | 3163 | const INTERNAL_SIZE_T oldsize = chunksize (oldp); |
f65fd747 | 3164 | |
fff94fa2 SP |
3165 | if (chunk_is_mmapped (oldp)) |
3166 | ar_ptr = NULL; | |
3167 | else | |
d5c3fafc DD |
3168 | { |
3169 | MAYBE_INIT_TCACHE (); | |
3170 | ar_ptr = arena_for_chunk (oldp); | |
3171 | } | |
fff94fa2 | 3172 | |
4cf6c72f FW |
3173 | /* Little security check which won't hurt performance: the allocator |
3174 | never wrapps around at the end of the address space. Therefore | |
3175 | we can exclude some size values which might appear here by | |
3176 | accident or by "design" from some intruder. We need to bypass | |
3177 | this check for dumped fake mmap chunks from the old main arena | |
3178 | because the new malloc may provide additional alignment. */ | |
3179 | if ((__builtin_expect ((uintptr_t) oldp > (uintptr_t) -oldsize, 0) | |
3180 | || __builtin_expect (misaligned_chunk (oldp), 0)) | |
3181 | && !DUMPED_MAIN_ARENA_CHUNK (oldp)) | |
ac3ed168 | 3182 | malloc_printerr ("realloc(): invalid pointer"); |
dc165f7b | 3183 | |
6c8dbf00 | 3184 | checked_request2size (bytes, nb); |
f65fd747 | 3185 | |
6c8dbf00 OB |
3186 | if (chunk_is_mmapped (oldp)) |
3187 | { | |
4cf6c72f FW |
3188 | /* If this is a faked mmapped chunk from the dumped main arena, |
3189 | always make a copy (and do not free the old chunk). */ | |
3190 | if (DUMPED_MAIN_ARENA_CHUNK (oldp)) | |
3191 | { | |
3192 | /* Must alloc, copy, free. */ | |
3193 | void *newmem = __libc_malloc (bytes); | |
3194 | if (newmem == 0) | |
3195 | return NULL; | |
3196 | /* Copy as many bytes as are available from the old chunk | |
1e8a8875 FW |
3197 | and fit into the new size. NB: The overhead for faked |
3198 | mmapped chunks is only SIZE_SZ, not 2 * SIZE_SZ as for | |
3199 | regular mmapped chunks. */ | |
3200 | if (bytes > oldsize - SIZE_SZ) | |
3201 | bytes = oldsize - SIZE_SZ; | |
4cf6c72f FW |
3202 | memcpy (newmem, oldmem, bytes); |
3203 | return newmem; | |
3204 | } | |
3205 | ||
6c8dbf00 | 3206 | void *newmem; |
f65fd747 | 3207 | |
fa8d436c | 3208 | #if HAVE_MREMAP |
6c8dbf00 OB |
3209 | newp = mremap_chunk (oldp, nb); |
3210 | if (newp) | |
3211 | return chunk2mem (newp); | |
f65fd747 | 3212 | #endif |
6c8dbf00 OB |
3213 | /* Note the extra SIZE_SZ overhead. */ |
3214 | if (oldsize - SIZE_SZ >= nb) | |
3215 | return oldmem; /* do nothing */ | |
3216 | ||
3217 | /* Must alloc, copy, free. */ | |
3218 | newmem = __libc_malloc (bytes); | |
3219 | if (newmem == 0) | |
3220 | return 0; /* propagate failure */ | |
fa8d436c | 3221 | |
6c8dbf00 OB |
3222 | memcpy (newmem, oldmem, oldsize - 2 * SIZE_SZ); |
3223 | munmap_chunk (oldp); | |
3224 | return newmem; | |
3225 | } | |
3226 | ||
3f6bb8a3 WD |
3227 | if (SINGLE_THREAD_P) |
3228 | { | |
3229 | newp = _int_realloc (ar_ptr, oldp, oldsize, nb); | |
3230 | assert (!newp || chunk_is_mmapped (mem2chunk (newp)) || | |
3231 | ar_ptr == arena_for_chunk (mem2chunk (newp))); | |
3232 | ||
3233 | return newp; | |
3234 | } | |
3235 | ||
4bf5f222 | 3236 | __libc_lock_lock (ar_ptr->mutex); |
f65fd747 | 3237 | |
6c8dbf00 | 3238 | newp = _int_realloc (ar_ptr, oldp, oldsize, nb); |
f65fd747 | 3239 | |
4bf5f222 | 3240 | __libc_lock_unlock (ar_ptr->mutex); |
6c8dbf00 OB |
3241 | assert (!newp || chunk_is_mmapped (mem2chunk (newp)) || |
3242 | ar_ptr == arena_for_chunk (mem2chunk (newp))); | |
07014fca UD |
3243 | |
3244 | if (newp == NULL) | |
3245 | { | |
3246 | /* Try harder to allocate memory in other arenas. */ | |
35fed6f1 | 3247 | LIBC_PROBE (memory_realloc_retry, 2, bytes, oldmem); |
6c8dbf00 | 3248 | newp = __libc_malloc (bytes); |
07014fca | 3249 | if (newp != NULL) |
6c8dbf00 OB |
3250 | { |
3251 | memcpy (newp, oldmem, oldsize - SIZE_SZ); | |
3252 | _int_free (ar_ptr, oldp, 0); | |
3253 | } | |
07014fca UD |
3254 | } |
3255 | ||
fa8d436c UD |
3256 | return newp; |
3257 | } | |
3b49edc0 | 3258 | libc_hidden_def (__libc_realloc) |
f65fd747 | 3259 | |
6c8dbf00 OB |
3260 | void * |
3261 | __libc_memalign (size_t alignment, size_t bytes) | |
10ad46bc OB |
3262 | { |
3263 | void *address = RETURN_ADDRESS (0); | |
3264 | return _mid_memalign (alignment, bytes, address); | |
3265 | } | |
3266 | ||
3267 | static void * | |
3268 | _mid_memalign (size_t alignment, size_t bytes, void *address) | |
fa8d436c UD |
3269 | { |
3270 | mstate ar_ptr; | |
22a89187 | 3271 | void *p; |
f65fd747 | 3272 | |
a222d91a | 3273 | void *(*hook) (size_t, size_t, const void *) = |
f3eeb3fc | 3274 | atomic_forced_read (__memalign_hook); |
bfacf1af | 3275 | if (__builtin_expect (hook != NULL, 0)) |
10ad46bc | 3276 | return (*hook)(alignment, bytes, address); |
f65fd747 | 3277 | |
10ad46bc | 3278 | /* If we need less alignment than we give anyway, just relay to malloc. */ |
6c8dbf00 OB |
3279 | if (alignment <= MALLOC_ALIGNMENT) |
3280 | return __libc_malloc (bytes); | |
1228ed5c | 3281 | |
fa8d436c | 3282 | /* Otherwise, ensure that it is at least a minimum chunk size */ |
6c8dbf00 OB |
3283 | if (alignment < MINSIZE) |
3284 | alignment = MINSIZE; | |
f65fd747 | 3285 | |
a56ee40b WN |
3286 | /* If the alignment is greater than SIZE_MAX / 2 + 1 it cannot be a |
3287 | power of 2 and will cause overflow in the check below. */ | |
3288 | if (alignment > SIZE_MAX / 2 + 1) | |
3289 | { | |
3290 | __set_errno (EINVAL); | |
3291 | return 0; | |
3292 | } | |
3293 | ||
b73ed247 WN |
3294 | /* Check for overflow. */ |
3295 | if (bytes > SIZE_MAX - alignment - MINSIZE) | |
3296 | { | |
3297 | __set_errno (ENOMEM); | |
3298 | return 0; | |
3299 | } | |
3300 | ||
10ad46bc OB |
3301 | |
3302 | /* Make sure alignment is power of 2. */ | |
6c8dbf00 OB |
3303 | if (!powerof2 (alignment)) |
3304 | { | |
3305 | size_t a = MALLOC_ALIGNMENT * 2; | |
3306 | while (a < alignment) | |
3307 | a <<= 1; | |
3308 | alignment = a; | |
3309 | } | |
10ad46bc | 3310 | |
3f6bb8a3 WD |
3311 | if (SINGLE_THREAD_P) |
3312 | { | |
3313 | p = _int_memalign (&main_arena, alignment, bytes); | |
3314 | assert (!p || chunk_is_mmapped (mem2chunk (p)) || | |
3315 | &main_arena == arena_for_chunk (mem2chunk (p))); | |
3316 | ||
3317 | return p; | |
3318 | } | |
3319 | ||
6c8dbf00 | 3320 | arena_get (ar_ptr, bytes + alignment + MINSIZE); |
6c8dbf00 OB |
3321 | |
3322 | p = _int_memalign (ar_ptr, alignment, bytes); | |
fff94fa2 | 3323 | if (!p && ar_ptr != NULL) |
6c8dbf00 OB |
3324 | { |
3325 | LIBC_PROBE (memory_memalign_retry, 2, bytes, alignment); | |
3326 | ar_ptr = arena_get_retry (ar_ptr, bytes); | |
fff94fa2 | 3327 | p = _int_memalign (ar_ptr, alignment, bytes); |
f65fd747 | 3328 | } |
fff94fa2 SP |
3329 | |
3330 | if (ar_ptr != NULL) | |
4bf5f222 | 3331 | __libc_lock_unlock (ar_ptr->mutex); |
fff94fa2 | 3332 | |
6c8dbf00 OB |
3333 | assert (!p || chunk_is_mmapped (mem2chunk (p)) || |
3334 | ar_ptr == arena_for_chunk (mem2chunk (p))); | |
fa8d436c | 3335 | return p; |
f65fd747 | 3336 | } |
380d7e87 | 3337 | /* For ISO C11. */ |
3b49edc0 UD |
3338 | weak_alias (__libc_memalign, aligned_alloc) |
3339 | libc_hidden_def (__libc_memalign) | |
f65fd747 | 3340 | |
6c8dbf00 OB |
3341 | void * |
3342 | __libc_valloc (size_t bytes) | |
fa8d436c | 3343 | { |
6c8dbf00 | 3344 | if (__malloc_initialized < 0) |
fa8d436c | 3345 | ptmalloc_init (); |
8088488d | 3346 | |
10ad46bc | 3347 | void *address = RETURN_ADDRESS (0); |
8a35c3fe CD |
3348 | size_t pagesize = GLRO (dl_pagesize); |
3349 | return _mid_memalign (pagesize, bytes, address); | |
fa8d436c | 3350 | } |
f65fd747 | 3351 | |
6c8dbf00 OB |
3352 | void * |
3353 | __libc_pvalloc (size_t bytes) | |
fa8d436c | 3354 | { |
6c8dbf00 | 3355 | if (__malloc_initialized < 0) |
fa8d436c | 3356 | ptmalloc_init (); |
8088488d | 3357 | |
10ad46bc | 3358 | void *address = RETURN_ADDRESS (0); |
8a35c3fe CD |
3359 | size_t pagesize = GLRO (dl_pagesize); |
3360 | size_t rounded_bytes = ALIGN_UP (bytes, pagesize); | |
dba38551 | 3361 | |
1159a193 | 3362 | /* Check for overflow. */ |
8a35c3fe | 3363 | if (bytes > SIZE_MAX - 2 * pagesize - MINSIZE) |
1159a193 WN |
3364 | { |
3365 | __set_errno (ENOMEM); | |
3366 | return 0; | |
3367 | } | |
3368 | ||
8a35c3fe | 3369 | return _mid_memalign (pagesize, rounded_bytes, address); |
fa8d436c | 3370 | } |
f65fd747 | 3371 | |
6c8dbf00 OB |
3372 | void * |
3373 | __libc_calloc (size_t n, size_t elem_size) | |
f65fd747 | 3374 | { |
d6285c9f CD |
3375 | mstate av; |
3376 | mchunkptr oldtop, p; | |
3377 | INTERNAL_SIZE_T bytes, sz, csz, oldtopsize; | |
6c8dbf00 | 3378 | void *mem; |
d6285c9f CD |
3379 | unsigned long clearsize; |
3380 | unsigned long nclears; | |
3381 | INTERNAL_SIZE_T *d; | |
0950889b UD |
3382 | |
3383 | /* size_t is unsigned so the behavior on overflow is defined. */ | |
3384 | bytes = n * elem_size; | |
d9af917d UD |
3385 | #define HALF_INTERNAL_SIZE_T \ |
3386 | (((INTERNAL_SIZE_T) 1) << (8 * sizeof (INTERNAL_SIZE_T) / 2)) | |
6c8dbf00 OB |
3387 | if (__builtin_expect ((n | elem_size) >= HALF_INTERNAL_SIZE_T, 0)) |
3388 | { | |
3389 | if (elem_size != 0 && bytes / elem_size != n) | |
3390 | { | |
3391 | __set_errno (ENOMEM); | |
3392 | return 0; | |
3393 | } | |
d9af917d | 3394 | } |
0950889b | 3395 | |
a222d91a | 3396 | void *(*hook) (size_t, const void *) = |
f3eeb3fc | 3397 | atomic_forced_read (__malloc_hook); |
6c8dbf00 OB |
3398 | if (__builtin_expect (hook != NULL, 0)) |
3399 | { | |
d6285c9f CD |
3400 | sz = bytes; |
3401 | mem = (*hook)(sz, RETURN_ADDRESS (0)); | |
3402 | if (mem == 0) | |
3403 | return 0; | |
3404 | ||
3405 | return memset (mem, 0, sz); | |
7799b7b3 | 3406 | } |
f65fd747 | 3407 | |
d6285c9f CD |
3408 | sz = bytes; |
3409 | ||
d5c3fafc DD |
3410 | MAYBE_INIT_TCACHE (); |
3411 | ||
3f6bb8a3 WD |
3412 | if (SINGLE_THREAD_P) |
3413 | av = &main_arena; | |
3414 | else | |
3415 | arena_get (av, sz); | |
3416 | ||
fff94fa2 SP |
3417 | if (av) |
3418 | { | |
3419 | /* Check if we hand out the top chunk, in which case there may be no | |
3420 | need to clear. */ | |
d6285c9f | 3421 | #if MORECORE_CLEARS |
fff94fa2 SP |
3422 | oldtop = top (av); |
3423 | oldtopsize = chunksize (top (av)); | |
d6285c9f | 3424 | # if MORECORE_CLEARS < 2 |
fff94fa2 SP |
3425 | /* Only newly allocated memory is guaranteed to be cleared. */ |
3426 | if (av == &main_arena && | |
3427 | oldtopsize < mp_.sbrk_base + av->max_system_mem - (char *) oldtop) | |
3428 | oldtopsize = (mp_.sbrk_base + av->max_system_mem - (char *) oldtop); | |
d6285c9f | 3429 | # endif |
fff94fa2 SP |
3430 | if (av != &main_arena) |
3431 | { | |
3432 | heap_info *heap = heap_for_ptr (oldtop); | |
3433 | if (oldtopsize < (char *) heap + heap->mprotect_size - (char *) oldtop) | |
3434 | oldtopsize = (char *) heap + heap->mprotect_size - (char *) oldtop; | |
3435 | } | |
3436 | #endif | |
3437 | } | |
3438 | else | |
d6285c9f | 3439 | { |
fff94fa2 SP |
3440 | /* No usable arenas. */ |
3441 | oldtop = 0; | |
3442 | oldtopsize = 0; | |
d6285c9f | 3443 | } |
d6285c9f CD |
3444 | mem = _int_malloc (av, sz); |
3445 | ||
d6285c9f CD |
3446 | assert (!mem || chunk_is_mmapped (mem2chunk (mem)) || |
3447 | av == arena_for_chunk (mem2chunk (mem))); | |
3448 | ||
3f6bb8a3 | 3449 | if (!SINGLE_THREAD_P) |
d6285c9f | 3450 | { |
3f6bb8a3 WD |
3451 | if (mem == 0 && av != NULL) |
3452 | { | |
3453 | LIBC_PROBE (memory_calloc_retry, 1, sz); | |
3454 | av = arena_get_retry (av, sz); | |
3455 | mem = _int_malloc (av, sz); | |
3456 | } | |
fff94fa2 | 3457 | |
3f6bb8a3 WD |
3458 | if (av != NULL) |
3459 | __libc_lock_unlock (av->mutex); | |
3460 | } | |
fff94fa2 SP |
3461 | |
3462 | /* Allocation failed even after a retry. */ | |
3463 | if (mem == 0) | |
3464 | return 0; | |
3465 | ||
d6285c9f CD |
3466 | p = mem2chunk (mem); |
3467 | ||
3468 | /* Two optional cases in which clearing not necessary */ | |
3469 | if (chunk_is_mmapped (p)) | |
3470 | { | |
3471 | if (__builtin_expect (perturb_byte, 0)) | |
3472 | return memset (mem, 0, sz); | |
3473 | ||
3474 | return mem; | |
3475 | } | |
3476 | ||
3477 | csz = chunksize (p); | |
3478 | ||
3479 | #if MORECORE_CLEARS | |
3480 | if (perturb_byte == 0 && (p == oldtop && csz > oldtopsize)) | |
3481 | { | |
3482 | /* clear only the bytes from non-freshly-sbrked memory */ | |
3483 | csz = oldtopsize; | |
3484 | } | |
3485 | #endif | |
3486 | ||
3487 | /* Unroll clear of <= 36 bytes (72 if 8byte sizes). We know that | |
3488 | contents have an odd number of INTERNAL_SIZE_T-sized words; | |
3489 | minimally 3. */ | |
3490 | d = (INTERNAL_SIZE_T *) mem; | |
3491 | clearsize = csz - SIZE_SZ; | |
3492 | nclears = clearsize / sizeof (INTERNAL_SIZE_T); | |
3493 | assert (nclears >= 3); | |
3494 | ||
3495 | if (nclears > 9) | |
3496 | return memset (d, 0, clearsize); | |
3497 | ||
3498 | else | |
3499 | { | |
3500 | *(d + 0) = 0; | |
3501 | *(d + 1) = 0; | |
3502 | *(d + 2) = 0; | |
3503 | if (nclears > 4) | |
3504 | { | |
3505 | *(d + 3) = 0; | |
3506 | *(d + 4) = 0; | |
3507 | if (nclears > 6) | |
3508 | { | |
3509 | *(d + 5) = 0; | |
3510 | *(d + 6) = 0; | |
3511 | if (nclears > 8) | |
3512 | { | |
3513 | *(d + 7) = 0; | |
3514 | *(d + 8) = 0; | |
3515 | } | |
3516 | } | |
3517 | } | |
3518 | } | |
3519 | ||
3520 | return mem; | |
fa8d436c | 3521 | } |
f65fd747 | 3522 | |
f65fd747 | 3523 | /* |
6c8dbf00 OB |
3524 | ------------------------------ malloc ------------------------------ |
3525 | */ | |
f65fd747 | 3526 | |
6c8dbf00 OB |
3527 | static void * |
3528 | _int_malloc (mstate av, size_t bytes) | |
f65fd747 | 3529 | { |
fa8d436c | 3530 | INTERNAL_SIZE_T nb; /* normalized request size */ |
6c8dbf00 OB |
3531 | unsigned int idx; /* associated bin index */ |
3532 | mbinptr bin; /* associated bin */ | |
f65fd747 | 3533 | |
6c8dbf00 | 3534 | mchunkptr victim; /* inspected/selected chunk */ |
fa8d436c | 3535 | INTERNAL_SIZE_T size; /* its size */ |
6c8dbf00 | 3536 | int victim_index; /* its bin index */ |
f65fd747 | 3537 | |
6c8dbf00 OB |
3538 | mchunkptr remainder; /* remainder from a split */ |
3539 | unsigned long remainder_size; /* its size */ | |
8a4b65b4 | 3540 | |
6c8dbf00 OB |
3541 | unsigned int block; /* bit map traverser */ |
3542 | unsigned int bit; /* bit map traverser */ | |
3543 | unsigned int map; /* current word of binmap */ | |
8a4b65b4 | 3544 | |
6c8dbf00 OB |
3545 | mchunkptr fwd; /* misc temp for linking */ |
3546 | mchunkptr bck; /* misc temp for linking */ | |
8a4b65b4 | 3547 | |
d5c3fafc DD |
3548 | #if USE_TCACHE |
3549 | size_t tcache_unsorted_count; /* count of unsorted chunks processed */ | |
3550 | #endif | |
3551 | ||
fa8d436c | 3552 | /* |
6c8dbf00 OB |
3553 | Convert request size to internal form by adding SIZE_SZ bytes |
3554 | overhead plus possibly more to obtain necessary alignment and/or | |
3555 | to obtain a size of at least MINSIZE, the smallest allocatable | |
3556 | size. Also, checked_request2size traps (returning 0) request sizes | |
3557 | that are so large that they wrap around zero when padded and | |
3558 | aligned. | |
3559 | */ | |
f65fd747 | 3560 | |
6c8dbf00 | 3561 | checked_request2size (bytes, nb); |
f65fd747 | 3562 | |
fff94fa2 SP |
3563 | /* There are no usable arenas. Fall back to sysmalloc to get a chunk from |
3564 | mmap. */ | |
3565 | if (__glibc_unlikely (av == NULL)) | |
3566 | { | |
3567 | void *p = sysmalloc (nb, av); | |
3568 | if (p != NULL) | |
3569 | alloc_perturb (p, bytes); | |
3570 | return p; | |
3571 | } | |
3572 | ||
fa8d436c | 3573 | /* |
6c8dbf00 OB |
3574 | If the size qualifies as a fastbin, first check corresponding bin. |
3575 | This code is safe to execute even if av is not yet initialized, so we | |
3576 | can try it without checking, which saves some time on this fast path. | |
3577 | */ | |
f65fd747 | 3578 | |
71effcea FW |
3579 | #define REMOVE_FB(fb, victim, pp) \ |
3580 | do \ | |
3581 | { \ | |
3582 | victim = pp; \ | |
3583 | if (victim == NULL) \ | |
3584 | break; \ | |
3585 | } \ | |
3586 | while ((pp = catomic_compare_and_exchange_val_acq (fb, victim->fd, victim)) \ | |
3587 | != victim); \ | |
3588 | ||
6c8dbf00 OB |
3589 | if ((unsigned long) (nb) <= (unsigned long) (get_max_fast ())) |
3590 | { | |
3591 | idx = fastbin_index (nb); | |
3592 | mfastbinptr *fb = &fastbin (av, idx); | |
71effcea FW |
3593 | mchunkptr pp; |
3594 | victim = *fb; | |
3595 | ||
905a7725 WD |
3596 | if (victim != NULL) |
3597 | { | |
71effcea FW |
3598 | if (SINGLE_THREAD_P) |
3599 | *fb = victim->fd; | |
3600 | else | |
3601 | REMOVE_FB (fb, pp, victim); | |
3602 | if (__glibc_likely (victim != NULL)) | |
6923f6db | 3603 | { |
71effcea FW |
3604 | size_t victim_idx = fastbin_index (chunksize (victim)); |
3605 | if (__builtin_expect (victim_idx != idx, 0)) | |
3606 | malloc_printerr ("malloc(): memory corruption (fast)"); | |
3607 | check_remalloced_chunk (av, victim, nb); | |
3608 | #if USE_TCACHE | |
3609 | /* While we're here, if we see other chunks of the same size, | |
3610 | stash them in the tcache. */ | |
3611 | size_t tc_idx = csize2tidx (nb); | |
3612 | if (tcache && tc_idx < mp_.tcache_bins) | |
d5c3fafc | 3613 | { |
71effcea FW |
3614 | mchunkptr tc_victim; |
3615 | ||
3616 | /* While bin not empty and tcache not full, copy chunks. */ | |
3617 | while (tcache->counts[tc_idx] < mp_.tcache_count | |
3618 | && (tc_victim = *fb) != NULL) | |
3619 | { | |
3620 | if (SINGLE_THREAD_P) | |
3621 | *fb = tc_victim->fd; | |
3622 | else | |
3623 | { | |
3624 | REMOVE_FB (fb, pp, tc_victim); | |
3625 | if (__glibc_unlikely (tc_victim == NULL)) | |
3626 | break; | |
3627 | } | |
3628 | tcache_put (tc_victim, tc_idx); | |
3629 | } | |
d5c3fafc | 3630 | } |
6923f6db | 3631 | #endif |
71effcea FW |
3632 | void *p = chunk2mem (victim); |
3633 | alloc_perturb (p, bytes); | |
3634 | return p; | |
3635 | } | |
905a7725 | 3636 | } |
fa8d436c | 3637 | } |
f65fd747 | 3638 | |
fa8d436c | 3639 | /* |
6c8dbf00 OB |
3640 | If a small request, check regular bin. Since these "smallbins" |
3641 | hold one size each, no searching within bins is necessary. | |
3642 | (For a large request, we need to wait until unsorted chunks are | |
3643 | processed to find best fit. But for small ones, fits are exact | |
3644 | anyway, so we can check now, which is faster.) | |
3645 | */ | |
3646 | ||
3647 | if (in_smallbin_range (nb)) | |
3648 | { | |
3649 | idx = smallbin_index (nb); | |
3650 | bin = bin_at (av, idx); | |
3651 | ||
3652 | if ((victim = last (bin)) != bin) | |
3653 | { | |
3381be5c WD |
3654 | bck = victim->bk; |
3655 | if (__glibc_unlikely (bck->fd != victim)) | |
3656 | malloc_printerr ("malloc(): smallbin double linked list corrupted"); | |
3657 | set_inuse_bit_at_offset (victim, nb); | |
3658 | bin->bk = bck; | |
3659 | bck->fd = bin; | |
3660 | ||
3661 | if (av != &main_arena) | |
3662 | set_non_main_arena (victim); | |
3663 | check_malloced_chunk (av, victim, nb); | |
d5c3fafc DD |
3664 | #if USE_TCACHE |
3665 | /* While we're here, if we see other chunks of the same size, | |
3666 | stash them in the tcache. */ | |
3667 | size_t tc_idx = csize2tidx (nb); | |
3668 | if (tcache && tc_idx < mp_.tcache_bins) | |
3669 | { | |
3670 | mchunkptr tc_victim; | |
3671 | ||
3672 | /* While bin not empty and tcache not full, copy chunks over. */ | |
3673 | while (tcache->counts[tc_idx] < mp_.tcache_count | |
3674 | && (tc_victim = last (bin)) != bin) | |
3675 | { | |
3676 | if (tc_victim != 0) | |
3677 | { | |
3678 | bck = tc_victim->bk; | |
3679 | set_inuse_bit_at_offset (tc_victim, nb); | |
3680 | if (av != &main_arena) | |
3681 | set_non_main_arena (tc_victim); | |
3682 | bin->bk = bck; | |
3683 | bck->fd = bin; | |
3684 | ||
3685 | tcache_put (tc_victim, tc_idx); | |
3686 | } | |
3687 | } | |
3688 | } | |
3689 | #endif | |
3381be5c WD |
3690 | void *p = chunk2mem (victim); |
3691 | alloc_perturb (p, bytes); | |
3692 | return p; | |
6c8dbf00 | 3693 | } |
fa8d436c | 3694 | } |
f65fd747 | 3695 | |
a9177ff5 | 3696 | /* |
fa8d436c UD |
3697 | If this is a large request, consolidate fastbins before continuing. |
3698 | While it might look excessive to kill all fastbins before | |
3699 | even seeing if there is space available, this avoids | |
3700 | fragmentation problems normally associated with fastbins. | |
3701 | Also, in practice, programs tend to have runs of either small or | |
a9177ff5 | 3702 | large requests, but less often mixtures, so consolidation is not |
fa8d436c UD |
3703 | invoked all that often in most programs. And the programs that |
3704 | it is called frequently in otherwise tend to fragment. | |
6c8dbf00 | 3705 | */ |
7799b7b3 | 3706 | |
6c8dbf00 OB |
3707 | else |
3708 | { | |
3709 | idx = largebin_index (nb); | |
e956075a | 3710 | if (atomic_load_relaxed (&av->have_fastchunks)) |
6c8dbf00 OB |
3711 | malloc_consolidate (av); |
3712 | } | |
f65fd747 | 3713 | |
fa8d436c | 3714 | /* |
6c8dbf00 OB |
3715 | Process recently freed or remaindered chunks, taking one only if |
3716 | it is exact fit, or, if this a small request, the chunk is remainder from | |
3717 | the most recent non-exact fit. Place other traversed chunks in | |
3718 | bins. Note that this step is the only place in any routine where | |
3719 | chunks are placed in bins. | |
3720 | ||
3721 | The outer loop here is needed because we might not realize until | |
3722 | near the end of malloc that we should have consolidated, so must | |
3723 | do so and retry. This happens at most once, and only when we would | |
3724 | otherwise need to expand memory to service a "small" request. | |
3725 | */ | |
3726 | ||
d5c3fafc DD |
3727 | #if USE_TCACHE |
3728 | INTERNAL_SIZE_T tcache_nb = 0; | |
3729 | size_t tc_idx = csize2tidx (nb); | |
3730 | if (tcache && tc_idx < mp_.tcache_bins) | |
3731 | tcache_nb = nb; | |
3732 | int return_cached = 0; | |
3733 | ||
3734 | tcache_unsorted_count = 0; | |
3735 | #endif | |
3736 | ||
6c8dbf00 OB |
3737 | for (;; ) |
3738 | { | |
3739 | int iters = 0; | |
3740 | while ((victim = unsorted_chunks (av)->bk) != unsorted_chunks (av)) | |
3741 | { | |
3742 | bck = victim->bk; | |
6c8dbf00 | 3743 | size = chunksize (victim); |
b90ddd08 IK |
3744 | mchunkptr next = chunk_at_offset (victim, size); |
3745 | ||
3746 | if (__glibc_unlikely (size <= 2 * SIZE_SZ) | |
3747 | || __glibc_unlikely (size > av->system_mem)) | |
3748 | malloc_printerr ("malloc(): invalid size (unsorted)"); | |
3749 | if (__glibc_unlikely (chunksize_nomask (next) < 2 * SIZE_SZ) | |
3750 | || __glibc_unlikely (chunksize_nomask (next) > av->system_mem)) | |
3751 | malloc_printerr ("malloc(): invalid next size (unsorted)"); | |
3752 | if (__glibc_unlikely ((prev_size (next) & ~(SIZE_BITS)) != size)) | |
3753 | malloc_printerr ("malloc(): mismatching next->prev_size (unsorted)"); | |
3754 | if (__glibc_unlikely (bck->fd != victim) | |
3755 | || __glibc_unlikely (victim->fd != unsorted_chunks (av))) | |
3756 | malloc_printerr ("malloc(): unsorted double linked list corrupted"); | |
35cfefd9 | 3757 | if (__glibc_unlikely (prev_inuse (next))) |
b90ddd08 | 3758 | malloc_printerr ("malloc(): invalid next->prev_inuse (unsorted)"); |
6c8dbf00 OB |
3759 | |
3760 | /* | |
3761 | If a small request, try to use last remainder if it is the | |
3762 | only chunk in unsorted bin. This helps promote locality for | |
3763 | runs of consecutive small requests. This is the only | |
3764 | exception to best-fit, and applies only when there is | |
3765 | no exact fit for a small chunk. | |
3766 | */ | |
3767 | ||
3768 | if (in_smallbin_range (nb) && | |
3769 | bck == unsorted_chunks (av) && | |
3770 | victim == av->last_remainder && | |
3771 | (unsigned long) (size) > (unsigned long) (nb + MINSIZE)) | |
3772 | { | |
3773 | /* split and reattach remainder */ | |
3774 | remainder_size = size - nb; | |
3775 | remainder = chunk_at_offset (victim, nb); | |
3776 | unsorted_chunks (av)->bk = unsorted_chunks (av)->fd = remainder; | |
3777 | av->last_remainder = remainder; | |
3778 | remainder->bk = remainder->fd = unsorted_chunks (av); | |
3779 | if (!in_smallbin_range (remainder_size)) | |
3780 | { | |
3781 | remainder->fd_nextsize = NULL; | |
3782 | remainder->bk_nextsize = NULL; | |
3783 | } | |
3784 | ||
3785 | set_head (victim, nb | PREV_INUSE | | |
3786 | (av != &main_arena ? NON_MAIN_ARENA : 0)); | |
3787 | set_head (remainder, remainder_size | PREV_INUSE); | |
3788 | set_foot (remainder, remainder_size); | |
3789 | ||
3790 | check_malloced_chunk (av, victim, nb); | |
3791 | void *p = chunk2mem (victim); | |
3792 | alloc_perturb (p, bytes); | |
3793 | return p; | |
3794 | } | |
3795 | ||
3796 | /* remove from unsorted list */ | |
bdc3009b FG |
3797 | if (__glibc_unlikely (bck->fd != victim)) |
3798 | malloc_printerr ("malloc(): corrupted unsorted chunks 3"); | |
6c8dbf00 OB |
3799 | unsorted_chunks (av)->bk = bck; |
3800 | bck->fd = unsorted_chunks (av); | |
3801 | ||
3802 | /* Take now instead of binning if exact fit */ | |
3803 | ||
3804 | if (size == nb) | |
3805 | { | |
3806 | set_inuse_bit_at_offset (victim, size); | |
3807 | if (av != &main_arena) | |
e9c4fe93 | 3808 | set_non_main_arena (victim); |
d5c3fafc DD |
3809 | #if USE_TCACHE |
3810 | /* Fill cache first, return to user only if cache fills. | |
3811 | We may return one of these chunks later. */ | |
3812 | if (tcache_nb | |
3813 | && tcache->counts[tc_idx] < mp_.tcache_count) | |
3814 | { | |
3815 | tcache_put (victim, tc_idx); | |
3816 | return_cached = 1; | |
3817 | continue; | |
3818 | } | |
3819 | else | |
3820 | { | |
3821 | #endif | |
6c8dbf00 OB |
3822 | check_malloced_chunk (av, victim, nb); |
3823 | void *p = chunk2mem (victim); | |
3824 | alloc_perturb (p, bytes); | |
3825 | return p; | |
d5c3fafc DD |
3826 | #if USE_TCACHE |
3827 | } | |
3828 | #endif | |
6c8dbf00 OB |
3829 | } |
3830 | ||
3831 | /* place chunk in bin */ | |
3832 | ||
3833 | if (in_smallbin_range (size)) | |
3834 | { | |
3835 | victim_index = smallbin_index (size); | |
3836 | bck = bin_at (av, victim_index); | |
3837 | fwd = bck->fd; | |
3838 | } | |
3839 | else | |
3840 | { | |
3841 | victim_index = largebin_index (size); | |
3842 | bck = bin_at (av, victim_index); | |
3843 | fwd = bck->fd; | |
3844 | ||
3845 | /* maintain large bins in sorted order */ | |
3846 | if (fwd != bck) | |
3847 | { | |
3848 | /* Or with inuse bit to speed comparisons */ | |
3849 | size |= PREV_INUSE; | |
3850 | /* if smaller than smallest, bypass loop below */ | |
e9c4fe93 FW |
3851 | assert (chunk_main_arena (bck->bk)); |
3852 | if ((unsigned long) (size) | |
3853 | < (unsigned long) chunksize_nomask (bck->bk)) | |
6c8dbf00 OB |
3854 | { |
3855 | fwd = bck; | |
3856 | bck = bck->bk; | |
3857 | ||
3858 | victim->fd_nextsize = fwd->fd; | |
3859 | victim->bk_nextsize = fwd->fd->bk_nextsize; | |
3860 | fwd->fd->bk_nextsize = victim->bk_nextsize->fd_nextsize = victim; | |
3861 | } | |
3862 | else | |
3863 | { | |
e9c4fe93 FW |
3864 | assert (chunk_main_arena (fwd)); |
3865 | while ((unsigned long) size < chunksize_nomask (fwd)) | |
6c8dbf00 OB |
3866 | { |
3867 | fwd = fwd->fd_nextsize; | |
e9c4fe93 | 3868 | assert (chunk_main_arena (fwd)); |
6c8dbf00 OB |
3869 | } |
3870 | ||
e9c4fe93 FW |
3871 | if ((unsigned long) size |
3872 | == (unsigned long) chunksize_nomask (fwd)) | |
6c8dbf00 OB |
3873 | /* Always insert in the second position. */ |
3874 | fwd = fwd->fd; | |
3875 | else | |
3876 | { | |
3877 | victim->fd_nextsize = fwd; | |
3878 | victim->bk_nextsize = fwd->bk_nextsize; | |
52b7cd6e AM |
3879 | if (__glibc_unlikely (fwd->bk_nextsize->fd_nextsize != fwd)) |
3880 | malloc_printerr ("malloc(): largebin double linked list corrupted (nextsize)"); | |
6c8dbf00 OB |
3881 | fwd->bk_nextsize = victim; |
3882 | victim->bk_nextsize->fd_nextsize = victim; | |
3883 | } | |
3884 | bck = fwd->bk; | |
52b7cd6e AM |
3885 | if (bck->fd != fwd) |
3886 | malloc_printerr ("malloc(): largebin double linked list corrupted (bk)"); | |
6c8dbf00 OB |
3887 | } |
3888 | } | |
3889 | else | |
3890 | victim->fd_nextsize = victim->bk_nextsize = victim; | |
3891 | } | |
3892 | ||
3893 | mark_bin (av, victim_index); | |
3894 | victim->bk = bck; | |
3895 | victim->fd = fwd; | |
3896 | fwd->bk = victim; | |
3897 | bck->fd = victim; | |
3898 | ||
d5c3fafc DD |
3899 | #if USE_TCACHE |
3900 | /* If we've processed as many chunks as we're allowed while | |
3901 | filling the cache, return one of the cached ones. */ | |
3902 | ++tcache_unsorted_count; | |
3903 | if (return_cached | |
3904 | && mp_.tcache_unsorted_limit > 0 | |
3905 | && tcache_unsorted_count > mp_.tcache_unsorted_limit) | |
3906 | { | |
3907 | return tcache_get (tc_idx); | |
3908 | } | |
3909 | #endif | |
3910 | ||
6c8dbf00 OB |
3911 | #define MAX_ITERS 10000 |
3912 | if (++iters >= MAX_ITERS) | |
3913 | break; | |
3914 | } | |
fa8d436c | 3915 | |
d5c3fafc DD |
3916 | #if USE_TCACHE |
3917 | /* If all the small chunks we found ended up cached, return one now. */ | |
3918 | if (return_cached) | |
3919 | { | |
3920 | return tcache_get (tc_idx); | |
3921 | } | |
3922 | #endif | |
3923 | ||
a9177ff5 | 3924 | /* |
6c8dbf00 OB |
3925 | If a large request, scan through the chunks of current bin in |
3926 | sorted order to find smallest that fits. Use the skip list for this. | |
3927 | */ | |
3928 | ||
3929 | if (!in_smallbin_range (nb)) | |
3930 | { | |
3931 | bin = bin_at (av, idx); | |
3932 | ||
3933 | /* skip scan if empty or largest chunk is too small */ | |
e9c4fe93 FW |
3934 | if ((victim = first (bin)) != bin |
3935 | && (unsigned long) chunksize_nomask (victim) | |
3936 | >= (unsigned long) (nb)) | |
6c8dbf00 OB |
3937 | { |
3938 | victim = victim->bk_nextsize; | |
3939 | while (((unsigned long) (size = chunksize (victim)) < | |
3940 | (unsigned long) (nb))) | |
3941 | victim = victim->bk_nextsize; | |
3942 | ||
3943 | /* Avoid removing the first entry for a size so that the skip | |
3944 | list does not have to be rerouted. */ | |
e9c4fe93 FW |
3945 | if (victim != last (bin) |
3946 | && chunksize_nomask (victim) | |
3947 | == chunksize_nomask (victim->fd)) | |
6c8dbf00 OB |
3948 | victim = victim->fd; |
3949 | ||
3950 | remainder_size = size - nb; | |
1ecba1fa | 3951 | unlink_chunk (av, victim); |
6c8dbf00 OB |
3952 | |
3953 | /* Exhaust */ | |
3954 | if (remainder_size < MINSIZE) | |
3955 | { | |
3956 | set_inuse_bit_at_offset (victim, size); | |
3957 | if (av != &main_arena) | |
e9c4fe93 | 3958 | set_non_main_arena (victim); |
6c8dbf00 OB |
3959 | } |
3960 | /* Split */ | |
3961 | else | |
3962 | { | |
3963 | remainder = chunk_at_offset (victim, nb); | |
3964 | /* We cannot assume the unsorted list is empty and therefore | |
3965 | have to perform a complete insert here. */ | |
3966 | bck = unsorted_chunks (av); | |
3967 | fwd = bck->fd; | |
ac3ed168 FW |
3968 | if (__glibc_unlikely (fwd->bk != bck)) |
3969 | malloc_printerr ("malloc(): corrupted unsorted chunks"); | |
6c8dbf00 OB |
3970 | remainder->bk = bck; |
3971 | remainder->fd = fwd; | |
3972 | bck->fd = remainder; | |
3973 | fwd->bk = remainder; | |
3974 | if (!in_smallbin_range (remainder_size)) | |
3975 | { | |
3976 | remainder->fd_nextsize = NULL; | |
3977 | remainder->bk_nextsize = NULL; | |
3978 | } | |
3979 | set_head (victim, nb | PREV_INUSE | | |
3980 | (av != &main_arena ? NON_MAIN_ARENA : 0)); | |
3981 | set_head (remainder, remainder_size | PREV_INUSE); | |
3982 | set_foot (remainder, remainder_size); | |
3983 | } | |
3984 | check_malloced_chunk (av, victim, nb); | |
3985 | void *p = chunk2mem (victim); | |
3986 | alloc_perturb (p, bytes); | |
3987 | return p; | |
3988 | } | |
3989 | } | |
f65fd747 | 3990 | |
6c8dbf00 OB |
3991 | /* |
3992 | Search for a chunk by scanning bins, starting with next largest | |
3993 | bin. This search is strictly by best-fit; i.e., the smallest | |
3994 | (with ties going to approximately the least recently used) chunk | |
3995 | that fits is selected. | |
3996 | ||
3997 | The bitmap avoids needing to check that most blocks are nonempty. | |
3998 | The particular case of skipping all bins during warm-up phases | |
3999 | when no chunks have been returned yet is faster than it might look. | |
4000 | */ | |
4001 | ||
4002 | ++idx; | |
4003 | bin = bin_at (av, idx); | |
4004 | block = idx2block (idx); | |
4005 | map = av->binmap[block]; | |
4006 | bit = idx2bit (idx); | |
4007 | ||
4008 | for (;; ) | |
4009 | { | |
4010 | /* Skip rest of block if there are no more set bits in this block. */ | |
4011 | if (bit > map || bit == 0) | |
4012 | { | |
4013 | do | |
4014 | { | |
4015 | if (++block >= BINMAPSIZE) /* out of bins */ | |
4016 | goto use_top; | |
4017 | } | |
4018 | while ((map = av->binmap[block]) == 0); | |
4019 | ||
4020 | bin = bin_at (av, (block << BINMAPSHIFT)); | |
4021 | bit = 1; | |
4022 | } | |
4023 | ||
4024 | /* Advance to bin with set bit. There must be one. */ | |
4025 | while ((bit & map) == 0) | |
4026 | { | |
4027 | bin = next_bin (bin); | |
4028 | bit <<= 1; | |
4029 | assert (bit != 0); | |
4030 | } | |
4031 | ||
4032 | /* Inspect the bin. It is likely to be non-empty */ | |
4033 | victim = last (bin); | |
4034 | ||
4035 | /* If a false alarm (empty bin), clear the bit. */ | |
4036 | if (victim == bin) | |
4037 | { | |
4038 | av->binmap[block] = map &= ~bit; /* Write through */ | |
4039 | bin = next_bin (bin); | |
4040 | bit <<= 1; | |
4041 | } | |
4042 | ||
4043 | else | |
4044 | { | |
4045 | size = chunksize (victim); | |
4046 | ||
4047 | /* We know the first chunk in this bin is big enough to use. */ | |
4048 | assert ((unsigned long) (size) >= (unsigned long) (nb)); | |
4049 | ||
4050 | remainder_size = size - nb; | |
4051 | ||
4052 | /* unlink */ | |
1ecba1fa | 4053 | unlink_chunk (av, victim); |
6c8dbf00 OB |
4054 | |
4055 | /* Exhaust */ | |
4056 | if (remainder_size < MINSIZE) | |
4057 | { | |
4058 | set_inuse_bit_at_offset (victim, size); | |
4059 | if (av != &main_arena) | |
e9c4fe93 | 4060 | set_non_main_arena (victim); |
6c8dbf00 OB |
4061 | } |
4062 | ||
4063 | /* Split */ | |
4064 | else | |
4065 | { | |
4066 | remainder = chunk_at_offset (victim, nb); | |
4067 | ||
4068 | /* We cannot assume the unsorted list is empty and therefore | |
4069 | have to perform a complete insert here. */ | |
4070 | bck = unsorted_chunks (av); | |
4071 | fwd = bck->fd; | |
ac3ed168 FW |
4072 | if (__glibc_unlikely (fwd->bk != bck)) |
4073 | malloc_printerr ("malloc(): corrupted unsorted chunks 2"); | |
6c8dbf00 OB |
4074 | remainder->bk = bck; |
4075 | remainder->fd = fwd; | |
4076 | bck->fd = remainder; | |
4077 | fwd->bk = remainder; | |
4078 | ||
4079 | /* advertise as last remainder */ | |
4080 | if (in_smallbin_range (nb)) | |
4081 | av->last_remainder = remainder; | |
4082 | if (!in_smallbin_range (remainder_size)) | |
4083 | { | |
4084 | remainder->fd_nextsize = NULL; | |
4085 | remainder->bk_nextsize = NULL; | |
4086 | } | |
4087 | set_head (victim, nb | PREV_INUSE | | |
4088 | (av != &main_arena ? NON_MAIN_ARENA : 0)); | |
4089 | set_head (remainder, remainder_size | PREV_INUSE); | |
4090 | set_foot (remainder, remainder_size); | |
4091 | } | |
4092 | check_malloced_chunk (av, victim, nb); | |
4093 | void *p = chunk2mem (victim); | |
4094 | alloc_perturb (p, bytes); | |
4095 | return p; | |
4096 | } | |
4097 | } | |
4098 | ||
4099 | use_top: | |
4100 | /* | |
4101 | If large enough, split off the chunk bordering the end of memory | |
4102 | (held in av->top). Note that this is in accord with the best-fit | |
4103 | search rule. In effect, av->top is treated as larger (and thus | |
4104 | less well fitting) than any other available chunk since it can | |
4105 | be extended to be as large as necessary (up to system | |
4106 | limitations). | |
4107 | ||
4108 | We require that av->top always exists (i.e., has size >= | |
4109 | MINSIZE) after initialization, so if it would otherwise be | |
4110 | exhausted by current request, it is replenished. (The main | |
4111 | reason for ensuring it exists is that we may need MINSIZE space | |
4112 | to put in fenceposts in sysmalloc.) | |
4113 | */ | |
4114 | ||
4115 | victim = av->top; | |
4116 | size = chunksize (victim); | |
4117 | ||
30a17d8c PC |
4118 | if (__glibc_unlikely (size > av->system_mem)) |
4119 | malloc_printerr ("malloc(): corrupted top size"); | |
4120 | ||
6c8dbf00 OB |
4121 | if ((unsigned long) (size) >= (unsigned long) (nb + MINSIZE)) |
4122 | { | |
4123 | remainder_size = size - nb; | |
4124 | remainder = chunk_at_offset (victim, nb); | |
4125 | av->top = remainder; | |
4126 | set_head (victim, nb | PREV_INUSE | | |
4127 | (av != &main_arena ? NON_MAIN_ARENA : 0)); | |
4128 | set_head (remainder, remainder_size | PREV_INUSE); | |
4129 | ||
4130 | check_malloced_chunk (av, victim, nb); | |
4131 | void *p = chunk2mem (victim); | |
4132 | alloc_perturb (p, bytes); | |
4133 | return p; | |
4134 | } | |
4135 | ||
4136 | /* When we are using atomic ops to free fast chunks we can get | |
4137 | here for all block sizes. */ | |
e956075a | 4138 | else if (atomic_load_relaxed (&av->have_fastchunks)) |
6c8dbf00 OB |
4139 | { |
4140 | malloc_consolidate (av); | |
4141 | /* restore original bin index */ | |
4142 | if (in_smallbin_range (nb)) | |
4143 | idx = smallbin_index (nb); | |
4144 | else | |
4145 | idx = largebin_index (nb); | |
4146 | } | |
f65fd747 | 4147 | |
6c8dbf00 OB |
4148 | /* |
4149 | Otherwise, relay to handle system-dependent cases | |
4150 | */ | |
425ce2ed | 4151 | else |
6c8dbf00 OB |
4152 | { |
4153 | void *p = sysmalloc (nb, av); | |
4154 | if (p != NULL) | |
4155 | alloc_perturb (p, bytes); | |
4156 | return p; | |
4157 | } | |
425ce2ed | 4158 | } |
fa8d436c | 4159 | } |
f65fd747 | 4160 | |
fa8d436c | 4161 | /* |
6c8dbf00 OB |
4162 | ------------------------------ free ------------------------------ |
4163 | */ | |
f65fd747 | 4164 | |
78ac92ad | 4165 | static void |
6c8dbf00 | 4166 | _int_free (mstate av, mchunkptr p, int have_lock) |
f65fd747 | 4167 | { |
fa8d436c | 4168 | INTERNAL_SIZE_T size; /* its size */ |
6c8dbf00 OB |
4169 | mfastbinptr *fb; /* associated fastbin */ |
4170 | mchunkptr nextchunk; /* next contiguous chunk */ | |
fa8d436c | 4171 | INTERNAL_SIZE_T nextsize; /* its size */ |
6c8dbf00 | 4172 | int nextinuse; /* true if nextchunk is used */ |
fa8d436c | 4173 | INTERNAL_SIZE_T prevsize; /* size of previous contiguous chunk */ |
6c8dbf00 OB |
4174 | mchunkptr bck; /* misc temp for linking */ |
4175 | mchunkptr fwd; /* misc temp for linking */ | |
fa8d436c | 4176 | |
6c8dbf00 | 4177 | size = chunksize (p); |
f65fd747 | 4178 | |
37fa1953 UD |
4179 | /* Little security check which won't hurt performance: the |
4180 | allocator never wrapps around at the end of the address space. | |
4181 | Therefore we can exclude some size values which might appear | |
4182 | here by accident or by "design" from some intruder. */ | |
dc165f7b | 4183 | if (__builtin_expect ((uintptr_t) p > (uintptr_t) -size, 0) |
073f560e | 4184 | || __builtin_expect (misaligned_chunk (p), 0)) |
ac3ed168 | 4185 | malloc_printerr ("free(): invalid pointer"); |
347c92e9 L |
4186 | /* We know that each chunk is at least MINSIZE bytes in size or a |
4187 | multiple of MALLOC_ALIGNMENT. */ | |
a1ffb40e | 4188 | if (__glibc_unlikely (size < MINSIZE || !aligned_OK (size))) |
ac3ed168 | 4189 | malloc_printerr ("free(): invalid size"); |
f65fd747 | 4190 | |
37fa1953 | 4191 | check_inuse_chunk(av, p); |
f65fd747 | 4192 | |
d5c3fafc DD |
4193 | #if USE_TCACHE |
4194 | { | |
4195 | size_t tc_idx = csize2tidx (size); | |
affec03b | 4196 | if (tcache != NULL && tc_idx < mp_.tcache_bins) |
d5c3fafc | 4197 | { |
affec03b FW |
4198 | /* Check to see if it's already in the tcache. */ |
4199 | tcache_entry *e = (tcache_entry *) chunk2mem (p); | |
4200 | ||
4201 | /* This test succeeds on double free. However, we don't 100% | |
4202 | trust it (it also matches random payload data at a 1 in | |
4203 | 2^<size_t> chance), so verify it's not an unlikely | |
4204 | coincidence before aborting. */ | |
4205 | if (__glibc_unlikely (e->key == tcache)) | |
4206 | { | |
4207 | tcache_entry *tmp; | |
4208 | LIBC_PROBE (memory_tcache_double_free, 2, e, tc_idx); | |
4209 | for (tmp = tcache->entries[tc_idx]; | |
4210 | tmp; | |
4211 | tmp = tmp->next) | |
4212 | if (tmp == e) | |
4213 | malloc_printerr ("free(): double free detected in tcache 2"); | |
4214 | /* If we get here, it was a coincidence. We've wasted a | |
4215 | few cycles, but don't abort. */ | |
4216 | } | |
4217 | ||
4218 | if (tcache->counts[tc_idx] < mp_.tcache_count) | |
4219 | { | |
4220 | tcache_put (p, tc_idx); | |
4221 | return; | |
4222 | } | |
d5c3fafc DD |
4223 | } |
4224 | } | |
4225 | #endif | |
4226 | ||
37fa1953 UD |
4227 | /* |
4228 | If eligible, place chunk on a fastbin so it can be found | |
4229 | and used quickly in malloc. | |
4230 | */ | |
6bf4302e | 4231 | |
9bf248c6 | 4232 | if ((unsigned long)(size) <= (unsigned long)(get_max_fast ()) |
6bf4302e | 4233 | |
37fa1953 UD |
4234 | #if TRIM_FASTBINS |
4235 | /* | |
4236 | If TRIM_FASTBINS set, don't place chunks | |
4237 | bordering top into fastbins | |
4238 | */ | |
4239 | && (chunk_at_offset(p, size) != av->top) | |
4240 | #endif | |
4241 | ) { | |
fa8d436c | 4242 | |
e9c4fe93 FW |
4243 | if (__builtin_expect (chunksize_nomask (chunk_at_offset (p, size)) |
4244 | <= 2 * SIZE_SZ, 0) | |
893e6098 UD |
4245 | || __builtin_expect (chunksize (chunk_at_offset (p, size)) |
4246 | >= av->system_mem, 0)) | |
4247 | { | |
d74e6f6c | 4248 | bool fail = true; |
bec466d9 | 4249 | /* We might not have a lock at this point and concurrent modifications |
d74e6f6c WD |
4250 | of system_mem might result in a false positive. Redo the test after |
4251 | getting the lock. */ | |
4252 | if (!have_lock) | |
4253 | { | |
4254 | __libc_lock_lock (av->mutex); | |
4255 | fail = (chunksize_nomask (chunk_at_offset (p, size)) <= 2 * SIZE_SZ | |
4256 | || chunksize (chunk_at_offset (p, size)) >= av->system_mem); | |
4257 | __libc_lock_unlock (av->mutex); | |
4258 | } | |
4259 | ||
4260 | if (fail) | |
ac3ed168 | 4261 | malloc_printerr ("free(): invalid next size (fast)"); |
893e6098 UD |
4262 | } |
4263 | ||
e8349efd | 4264 | free_perturb (chunk2mem(p), size - 2 * SIZE_SZ); |
425ce2ed | 4265 | |
e956075a | 4266 | atomic_store_relaxed (&av->have_fastchunks, true); |
90a3055e UD |
4267 | unsigned int idx = fastbin_index(size); |
4268 | fb = &fastbin (av, idx); | |
425ce2ed | 4269 | |
362b47fe | 4270 | /* Atomically link P to its fastbin: P->FD = *FB; *FB = P; */ |
71effcea FW |
4271 | mchunkptr old = *fb, old2; |
4272 | ||
4273 | if (SINGLE_THREAD_P) | |
4274 | { | |
4275 | /* Check that the top of the bin is not the record we are going to | |
4276 | add (i.e., double free). */ | |
4277 | if (__builtin_expect (old == p, 0)) | |
4278 | malloc_printerr ("double free or corruption (fasttop)"); | |
4279 | p->fd = old; | |
4280 | *fb = p; | |
4281 | } | |
4282 | else | |
4283 | do | |
4284 | { | |
4285 | /* Check that the top of the bin is not the record we are going to | |
4286 | add (i.e., double free). */ | |
4287 | if (__builtin_expect (old == p, 0)) | |
4288 | malloc_printerr ("double free or corruption (fasttop)"); | |
4289 | p->fd = old2 = old; | |
4290 | } | |
4291 | while ((old = catomic_compare_and_exchange_val_rel (fb, p, old2)) | |
4292 | != old2); | |
a15d53e2 WD |
4293 | |
4294 | /* Check that size of fastbin chunk at the top is the same as | |
4295 | size of the chunk that we are adding. We can dereference OLD | |
4296 | only if we have the lock, otherwise it might have already been | |
4297 | allocated again. */ | |
4298 | if (have_lock && old != NULL | |
4299 | && __builtin_expect (fastbin_index (chunksize (old)) != idx, 0)) | |
ac3ed168 | 4300 | malloc_printerr ("invalid fastbin entry (free)"); |
37fa1953 | 4301 | } |
f65fd747 | 4302 | |
37fa1953 UD |
4303 | /* |
4304 | Consolidate other non-mmapped chunks as they arrive. | |
4305 | */ | |
fa8d436c | 4306 | |
37fa1953 | 4307 | else if (!chunk_is_mmapped(p)) { |
a15d53e2 WD |
4308 | |
4309 | /* If we're single-threaded, don't lock the arena. */ | |
4310 | if (SINGLE_THREAD_P) | |
4311 | have_lock = true; | |
4312 | ||
24cffce7 | 4313 | if (!have_lock) |
4bf5f222 | 4314 | __libc_lock_lock (av->mutex); |
425ce2ed | 4315 | |
37fa1953 | 4316 | nextchunk = chunk_at_offset(p, size); |
fa8d436c | 4317 | |
37fa1953 UD |
4318 | /* Lightweight tests: check whether the block is already the |
4319 | top block. */ | |
a1ffb40e | 4320 | if (__glibc_unlikely (p == av->top)) |
ac3ed168 | 4321 | malloc_printerr ("double free or corruption (top)"); |
37fa1953 UD |
4322 | /* Or whether the next chunk is beyond the boundaries of the arena. */ |
4323 | if (__builtin_expect (contiguous (av) | |
4324 | && (char *) nextchunk | |
4325 | >= ((char *) av->top + chunksize(av->top)), 0)) | |
ac3ed168 | 4326 | malloc_printerr ("double free or corruption (out)"); |
37fa1953 | 4327 | /* Or whether the block is actually not marked used. */ |
a1ffb40e | 4328 | if (__glibc_unlikely (!prev_inuse(nextchunk))) |
ac3ed168 | 4329 | malloc_printerr ("double free or corruption (!prev)"); |
fa8d436c | 4330 | |
37fa1953 | 4331 | nextsize = chunksize(nextchunk); |
e9c4fe93 | 4332 | if (__builtin_expect (chunksize_nomask (nextchunk) <= 2 * SIZE_SZ, 0) |
893e6098 | 4333 | || __builtin_expect (nextsize >= av->system_mem, 0)) |
ac3ed168 | 4334 | malloc_printerr ("free(): invalid next size (normal)"); |
fa8d436c | 4335 | |
e8349efd | 4336 | free_perturb (chunk2mem(p), size - 2 * SIZE_SZ); |
854278df | 4337 | |
37fa1953 UD |
4338 | /* consolidate backward */ |
4339 | if (!prev_inuse(p)) { | |
e9c4fe93 | 4340 | prevsize = prev_size (p); |
37fa1953 UD |
4341 | size += prevsize; |
4342 | p = chunk_at_offset(p, -((long) prevsize)); | |
d6db68e6 ME |
4343 | if (__glibc_unlikely (chunksize(p) != prevsize)) |
4344 | malloc_printerr ("corrupted size vs. prev_size while consolidating"); | |
1ecba1fa | 4345 | unlink_chunk (av, p); |
37fa1953 | 4346 | } |
a9177ff5 | 4347 | |
37fa1953 UD |
4348 | if (nextchunk != av->top) { |
4349 | /* get and clear inuse bit */ | |
4350 | nextinuse = inuse_bit_at_offset(nextchunk, nextsize); | |
4351 | ||
4352 | /* consolidate forward */ | |
4353 | if (!nextinuse) { | |
1ecba1fa | 4354 | unlink_chunk (av, nextchunk); |
37fa1953 UD |
4355 | size += nextsize; |
4356 | } else | |
4357 | clear_inuse_bit_at_offset(nextchunk, 0); | |
10dc2a90 | 4358 | |
fa8d436c | 4359 | /* |
37fa1953 UD |
4360 | Place the chunk in unsorted chunk list. Chunks are |
4361 | not placed into regular bins until after they have | |
4362 | been given one chance to be used in malloc. | |
fa8d436c | 4363 | */ |
f65fd747 | 4364 | |
37fa1953 UD |
4365 | bck = unsorted_chunks(av); |
4366 | fwd = bck->fd; | |
a1ffb40e | 4367 | if (__glibc_unlikely (fwd->bk != bck)) |
ac3ed168 | 4368 | malloc_printerr ("free(): corrupted unsorted chunks"); |
37fa1953 | 4369 | p->fd = fwd; |
7ecfbd38 UD |
4370 | p->bk = bck; |
4371 | if (!in_smallbin_range(size)) | |
4372 | { | |
4373 | p->fd_nextsize = NULL; | |
4374 | p->bk_nextsize = NULL; | |
4375 | } | |
37fa1953 UD |
4376 | bck->fd = p; |
4377 | fwd->bk = p; | |
8a4b65b4 | 4378 | |
37fa1953 UD |
4379 | set_head(p, size | PREV_INUSE); |
4380 | set_foot(p, size); | |
4381 | ||
4382 | check_free_chunk(av, p); | |
4383 | } | |
4384 | ||
4385 | /* | |
4386 | If the chunk borders the current high end of memory, | |
4387 | consolidate into top | |
4388 | */ | |
4389 | ||
4390 | else { | |
4391 | size += nextsize; | |
4392 | set_head(p, size | PREV_INUSE); | |
4393 | av->top = p; | |
4394 | check_chunk(av, p); | |
4395 | } | |
4396 | ||
4397 | /* | |
4398 | If freeing a large space, consolidate possibly-surrounding | |
4399 | chunks. Then, if the total unused topmost memory exceeds trim | |
4400 | threshold, ask malloc_trim to reduce top. | |
4401 | ||
4402 | Unless max_fast is 0, we don't know if there are fastbins | |
4403 | bordering top, so we cannot tell for sure whether threshold | |
4404 | has been reached unless fastbins are consolidated. But we | |
4405 | don't want to consolidate on each free. As a compromise, | |
4406 | consolidation is performed if FASTBIN_CONSOLIDATION_THRESHOLD | |
4407 | is reached. | |
4408 | */ | |
fa8d436c | 4409 | |
37fa1953 | 4410 | if ((unsigned long)(size) >= FASTBIN_CONSOLIDATION_THRESHOLD) { |
e956075a | 4411 | if (atomic_load_relaxed (&av->have_fastchunks)) |
37fa1953 | 4412 | malloc_consolidate(av); |
fa8d436c | 4413 | |
37fa1953 | 4414 | if (av == &main_arena) { |
a9177ff5 | 4415 | #ifndef MORECORE_CANNOT_TRIM |
37fa1953 UD |
4416 | if ((unsigned long)(chunksize(av->top)) >= |
4417 | (unsigned long)(mp_.trim_threshold)) | |
3b49edc0 | 4418 | systrim(mp_.top_pad, av); |
fa8d436c | 4419 | #endif |
37fa1953 UD |
4420 | } else { |
4421 | /* Always try heap_trim(), even if the top chunk is not | |
4422 | large, because the corresponding heap might go away. */ | |
4423 | heap_info *heap = heap_for_ptr(top(av)); | |
fa8d436c | 4424 | |
37fa1953 UD |
4425 | assert(heap->ar_ptr == av); |
4426 | heap_trim(heap, mp_.top_pad); | |
fa8d436c | 4427 | } |
fa8d436c | 4428 | } |
10dc2a90 | 4429 | |
24cffce7 | 4430 | if (!have_lock) |
4bf5f222 | 4431 | __libc_lock_unlock (av->mutex); |
37fa1953 UD |
4432 | } |
4433 | /* | |
22a89187 | 4434 | If the chunk was allocated via mmap, release via munmap(). |
37fa1953 UD |
4435 | */ |
4436 | ||
4437 | else { | |
c120d94d | 4438 | munmap_chunk (p); |
fa8d436c | 4439 | } |
10dc2a90 UD |
4440 | } |
4441 | ||
fa8d436c UD |
4442 | /* |
4443 | ------------------------- malloc_consolidate ------------------------- | |
4444 | ||
4445 | malloc_consolidate is a specialized version of free() that tears | |
4446 | down chunks held in fastbins. Free itself cannot be used for this | |
4447 | purpose since, among other things, it might place chunks back onto | |
4448 | fastbins. So, instead, we need to use a minor variant of the same | |
4449 | code. | |
fa8d436c UD |
4450 | */ |
4451 | ||
fa8d436c | 4452 | static void malloc_consolidate(mstate av) |
10dc2a90 | 4453 | { |
fa8d436c UD |
4454 | mfastbinptr* fb; /* current fastbin being consolidated */ |
4455 | mfastbinptr* maxfb; /* last fastbin (for loop control) */ | |
4456 | mchunkptr p; /* current chunk being consolidated */ | |
4457 | mchunkptr nextp; /* next chunk to consolidate */ | |
4458 | mchunkptr unsorted_bin; /* bin header */ | |
4459 | mchunkptr first_unsorted; /* chunk to link to */ | |
4460 | ||
4461 | /* These have same use as in free() */ | |
4462 | mchunkptr nextchunk; | |
4463 | INTERNAL_SIZE_T size; | |
4464 | INTERNAL_SIZE_T nextsize; | |
4465 | INTERNAL_SIZE_T prevsize; | |
4466 | int nextinuse; | |
10dc2a90 | 4467 | |
3381be5c | 4468 | atomic_store_relaxed (&av->have_fastchunks, false); |
10dc2a90 | 4469 | |
3381be5c | 4470 | unsorted_bin = unsorted_chunks(av); |
a9177ff5 | 4471 | |
3381be5c WD |
4472 | /* |
4473 | Remove each chunk from fast bin and consolidate it, placing it | |
4474 | then in unsorted bin. Among other reasons for doing this, | |
4475 | placing in unsorted bin avoids needing to calculate actual bins | |
4476 | until malloc is sure that chunks aren't immediately going to be | |
4477 | reused anyway. | |
4478 | */ | |
72f90263 | 4479 | |
3381be5c WD |
4480 | maxfb = &fastbin (av, NFASTBINS - 1); |
4481 | fb = &fastbin (av, 0); | |
4482 | do { | |
71effcea | 4483 | p = atomic_exchange_acq (fb, NULL); |
3381be5c WD |
4484 | if (p != 0) { |
4485 | do { | |
249a5895 IK |
4486 | { |
4487 | unsigned int idx = fastbin_index (chunksize (p)); | |
4488 | if ((&fastbin (av, idx)) != fb) | |
4489 | malloc_printerr ("malloc_consolidate(): invalid chunk size"); | |
4490 | } | |
4491 | ||
3381be5c WD |
4492 | check_inuse_chunk(av, p); |
4493 | nextp = p->fd; | |
4494 | ||
4495 | /* Slightly streamlined version of consolidation code in free() */ | |
4496 | size = chunksize (p); | |
4497 | nextchunk = chunk_at_offset(p, size); | |
4498 | nextsize = chunksize(nextchunk); | |
4499 | ||
4500 | if (!prev_inuse(p)) { | |
4501 | prevsize = prev_size (p); | |
4502 | size += prevsize; | |
4503 | p = chunk_at_offset(p, -((long) prevsize)); | |
d6db68e6 ME |
4504 | if (__glibc_unlikely (chunksize(p) != prevsize)) |
4505 | malloc_printerr ("corrupted size vs. prev_size in fastbins"); | |
1ecba1fa | 4506 | unlink_chunk (av, p); |
3381be5c | 4507 | } |
72f90263 | 4508 | |
3381be5c WD |
4509 | if (nextchunk != av->top) { |
4510 | nextinuse = inuse_bit_at_offset(nextchunk, nextsize); | |
a9177ff5 | 4511 | |
3381be5c WD |
4512 | if (!nextinuse) { |
4513 | size += nextsize; | |
1ecba1fa | 4514 | unlink_chunk (av, nextchunk); |
3381be5c WD |
4515 | } else |
4516 | clear_inuse_bit_at_offset(nextchunk, 0); | |
a9177ff5 | 4517 | |
3381be5c WD |
4518 | first_unsorted = unsorted_bin->fd; |
4519 | unsorted_bin->fd = p; | |
4520 | first_unsorted->bk = p; | |
7ecfbd38 | 4521 | |
3381be5c WD |
4522 | if (!in_smallbin_range (size)) { |
4523 | p->fd_nextsize = NULL; | |
4524 | p->bk_nextsize = NULL; | |
72f90263 | 4525 | } |
a9177ff5 | 4526 | |
3381be5c WD |
4527 | set_head(p, size | PREV_INUSE); |
4528 | p->bk = unsorted_bin; | |
4529 | p->fd = first_unsorted; | |
4530 | set_foot(p, size); | |
4531 | } | |
a9177ff5 | 4532 | |
3381be5c WD |
4533 | else { |
4534 | size += nextsize; | |
4535 | set_head(p, size | PREV_INUSE); | |
4536 | av->top = p; | |
4537 | } | |
a9177ff5 | 4538 | |
3381be5c WD |
4539 | } while ( (p = nextp) != 0); |
4540 | ||
4541 | } | |
4542 | } while (fb++ != maxfb); | |
fa8d436c | 4543 | } |
10dc2a90 | 4544 | |
fa8d436c UD |
4545 | /* |
4546 | ------------------------------ realloc ------------------------------ | |
4547 | */ | |
f65fd747 | 4548 | |
22a89187 | 4549 | void* |
4c8b8cc3 UD |
4550 | _int_realloc(mstate av, mchunkptr oldp, INTERNAL_SIZE_T oldsize, |
4551 | INTERNAL_SIZE_T nb) | |
fa8d436c | 4552 | { |
fa8d436c UD |
4553 | mchunkptr newp; /* chunk to return */ |
4554 | INTERNAL_SIZE_T newsize; /* its size */ | |
22a89187 | 4555 | void* newmem; /* corresponding user mem */ |
f65fd747 | 4556 | |
fa8d436c | 4557 | mchunkptr next; /* next contiguous chunk after oldp */ |
f65fd747 | 4558 | |
fa8d436c UD |
4559 | mchunkptr remainder; /* extra space at end of newp */ |
4560 | unsigned long remainder_size; /* its size */ | |
f65fd747 | 4561 | |
6dd6a580 | 4562 | /* oldmem size */ |
e9c4fe93 | 4563 | if (__builtin_expect (chunksize_nomask (oldp) <= 2 * SIZE_SZ, 0) |
76761b63 | 4564 | || __builtin_expect (oldsize >= av->system_mem, 0)) |
ac3ed168 | 4565 | malloc_printerr ("realloc(): invalid old size"); |
76761b63 | 4566 | |
6c8dbf00 | 4567 | check_inuse_chunk (av, oldp); |
f65fd747 | 4568 | |
4c8b8cc3 | 4569 | /* All callers already filter out mmap'ed chunks. */ |
6c8dbf00 | 4570 | assert (!chunk_is_mmapped (oldp)); |
f65fd747 | 4571 | |
6c8dbf00 OB |
4572 | next = chunk_at_offset (oldp, oldsize); |
4573 | INTERNAL_SIZE_T nextsize = chunksize (next); | |
e9c4fe93 | 4574 | if (__builtin_expect (chunksize_nomask (next) <= 2 * SIZE_SZ, 0) |
22a89187 | 4575 | || __builtin_expect (nextsize >= av->system_mem, 0)) |
ac3ed168 | 4576 | malloc_printerr ("realloc(): invalid next size"); |
22a89187 | 4577 | |
6c8dbf00 OB |
4578 | if ((unsigned long) (oldsize) >= (unsigned long) (nb)) |
4579 | { | |
4580 | /* already big enough; split below */ | |
fa8d436c | 4581 | newp = oldp; |
6c8dbf00 | 4582 | newsize = oldsize; |
7799b7b3 | 4583 | } |
f65fd747 | 4584 | |
6c8dbf00 OB |
4585 | else |
4586 | { | |
4587 | /* Try to expand forward into top */ | |
4588 | if (next == av->top && | |
4589 | (unsigned long) (newsize = oldsize + nextsize) >= | |
4590 | (unsigned long) (nb + MINSIZE)) | |
4591 | { | |
4592 | set_head_size (oldp, nb | (av != &main_arena ? NON_MAIN_ARENA : 0)); | |
4593 | av->top = chunk_at_offset (oldp, nb); | |
4594 | set_head (av->top, (newsize - nb) | PREV_INUSE); | |
4595 | check_inuse_chunk (av, oldp); | |
4596 | return chunk2mem (oldp); | |
4597 | } | |
4598 | ||
4599 | /* Try to expand forward into next chunk; split off remainder below */ | |
4600 | else if (next != av->top && | |
4601 | !inuse (next) && | |
4602 | (unsigned long) (newsize = oldsize + nextsize) >= | |
4603 | (unsigned long) (nb)) | |
4604 | { | |
4605 | newp = oldp; | |
1ecba1fa | 4606 | unlink_chunk (av, next); |
6c8dbf00 OB |
4607 | } |
4608 | ||
4609 | /* allocate, copy, free */ | |
4610 | else | |
4611 | { | |
4612 | newmem = _int_malloc (av, nb - MALLOC_ALIGN_MASK); | |
4613 | if (newmem == 0) | |
4614 | return 0; /* propagate failure */ | |
4615 | ||
4616 | newp = mem2chunk (newmem); | |
4617 | newsize = chunksize (newp); | |
4618 | ||
4619 | /* | |
4620 | Avoid copy if newp is next chunk after oldp. | |
4621 | */ | |
4622 | if (newp == next) | |
4623 | { | |
4624 | newsize += oldsize; | |
4625 | newp = oldp; | |
4626 | } | |
4627 | else | |
4628 | { | |
b50dd3bc | 4629 | memcpy (newmem, chunk2mem (oldp), oldsize - SIZE_SZ); |
6c8dbf00 OB |
4630 | _int_free (av, oldp, 1); |
4631 | check_inuse_chunk (av, newp); | |
4632 | return chunk2mem (newp); | |
4633 | } | |
4634 | } | |
fa8d436c | 4635 | } |
f65fd747 | 4636 | |
22a89187 | 4637 | /* If possible, free extra space in old or extended chunk */ |
f65fd747 | 4638 | |
6c8dbf00 | 4639 | assert ((unsigned long) (newsize) >= (unsigned long) (nb)); |
f65fd747 | 4640 | |
22a89187 | 4641 | remainder_size = newsize - nb; |
10dc2a90 | 4642 | |
6c8dbf00 OB |
4643 | if (remainder_size < MINSIZE) /* not enough extra to split off */ |
4644 | { | |
4645 | set_head_size (newp, newsize | (av != &main_arena ? NON_MAIN_ARENA : 0)); | |
4646 | set_inuse_bit_at_offset (newp, newsize); | |
4647 | } | |
4648 | else /* split remainder */ | |
4649 | { | |
4650 | remainder = chunk_at_offset (newp, nb); | |
4651 | set_head_size (newp, nb | (av != &main_arena ? NON_MAIN_ARENA : 0)); | |
4652 | set_head (remainder, remainder_size | PREV_INUSE | | |
4653 | (av != &main_arena ? NON_MAIN_ARENA : 0)); | |
4654 | /* Mark remainder as inuse so free() won't complain */ | |
4655 | set_inuse_bit_at_offset (remainder, remainder_size); | |
4656 | _int_free (av, remainder, 1); | |
4657 | } | |
22a89187 | 4658 | |
6c8dbf00 OB |
4659 | check_inuse_chunk (av, newp); |
4660 | return chunk2mem (newp); | |
fa8d436c UD |
4661 | } |
4662 | ||
4663 | /* | |
6c8dbf00 OB |
4664 | ------------------------------ memalign ------------------------------ |
4665 | */ | |
fa8d436c | 4666 | |
6c8dbf00 OB |
4667 | static void * |
4668 | _int_memalign (mstate av, size_t alignment, size_t bytes) | |
fa8d436c UD |
4669 | { |
4670 | INTERNAL_SIZE_T nb; /* padded request size */ | |
6c8dbf00 OB |
4671 | char *m; /* memory returned by malloc call */ |
4672 | mchunkptr p; /* corresponding chunk */ | |
4673 | char *brk; /* alignment point within p */ | |
4674 | mchunkptr newp; /* chunk to return */ | |
fa8d436c UD |
4675 | INTERNAL_SIZE_T newsize; /* its size */ |
4676 | INTERNAL_SIZE_T leadsize; /* leading space before alignment point */ | |
6c8dbf00 OB |
4677 | mchunkptr remainder; /* spare room at end to split off */ |
4678 | unsigned long remainder_size; /* its size */ | |
fa8d436c | 4679 | INTERNAL_SIZE_T size; |
f65fd747 | 4680 | |
f65fd747 | 4681 | |
f65fd747 | 4682 | |
6c8dbf00 | 4683 | checked_request2size (bytes, nb); |
fa8d436c UD |
4684 | |
4685 | /* | |
6c8dbf00 OB |
4686 | Strategy: find a spot within that chunk that meets the alignment |
4687 | request, and then possibly free the leading and trailing space. | |
4688 | */ | |
fa8d436c UD |
4689 | |
4690 | ||
8e448310 AS |
4691 | /* Check for overflow. */ |
4692 | if (nb > SIZE_MAX - alignment - MINSIZE) | |
4693 | { | |
4694 | __set_errno (ENOMEM); | |
4695 | return 0; | |
4696 | } | |
4697 | ||
fa8d436c UD |
4698 | /* Call malloc with worst case padding to hit alignment. */ |
4699 | ||
6c8dbf00 OB |
4700 | m = (char *) (_int_malloc (av, nb + alignment + MINSIZE)); |
4701 | ||
4702 | if (m == 0) | |
4703 | return 0; /* propagate failure */ | |
4704 | ||
4705 | p = mem2chunk (m); | |
4706 | ||
4707 | if ((((unsigned long) (m)) % alignment) != 0) /* misaligned */ | |
4708 | ||
4709 | { /* | |
4710 | Find an aligned spot inside chunk. Since we need to give back | |
4711 | leading space in a chunk of at least MINSIZE, if the first | |
4712 | calculation places us at a spot with less than MINSIZE leader, | |
4713 | we can move to the next aligned spot -- we've allocated enough | |
4714 | total room so that this is always possible. | |
4715 | */ | |
4716 | brk = (char *) mem2chunk (((unsigned long) (m + alignment - 1)) & | |
4717 | - ((signed long) alignment)); | |
4718 | if ((unsigned long) (brk - (char *) (p)) < MINSIZE) | |
4719 | brk += alignment; | |
4720 | ||
4721 | newp = (mchunkptr) brk; | |
4722 | leadsize = brk - (char *) (p); | |
4723 | newsize = chunksize (p) - leadsize; | |
4724 | ||
4725 | /* For mmapped chunks, just adjust offset */ | |
4726 | if (chunk_is_mmapped (p)) | |
4727 | { | |
e9c4fe93 | 4728 | set_prev_size (newp, prev_size (p) + leadsize); |
6c8dbf00 OB |
4729 | set_head (newp, newsize | IS_MMAPPED); |
4730 | return chunk2mem (newp); | |
4731 | } | |
4732 | ||
4733 | /* Otherwise, give back leader, use the rest */ | |
4734 | set_head (newp, newsize | PREV_INUSE | | |
4735 | (av != &main_arena ? NON_MAIN_ARENA : 0)); | |
4736 | set_inuse_bit_at_offset (newp, newsize); | |
4737 | set_head_size (p, leadsize | (av != &main_arena ? NON_MAIN_ARENA : 0)); | |
4738 | _int_free (av, p, 1); | |
4739 | p = newp; | |
4740 | ||
4741 | assert (newsize >= nb && | |
4742 | (((unsigned long) (chunk2mem (p))) % alignment) == 0); | |
f65fd747 | 4743 | } |
f65fd747 | 4744 | |
f65fd747 | 4745 | /* Also give back spare room at the end */ |
6c8dbf00 OB |
4746 | if (!chunk_is_mmapped (p)) |
4747 | { | |
4748 | size = chunksize (p); | |
4749 | if ((unsigned long) (size) > (unsigned long) (nb + MINSIZE)) | |
4750 | { | |
4751 | remainder_size = size - nb; | |
4752 | remainder = chunk_at_offset (p, nb); | |
4753 | set_head (remainder, remainder_size | PREV_INUSE | | |
4754 | (av != &main_arena ? NON_MAIN_ARENA : 0)); | |
4755 | set_head_size (p, nb); | |
4756 | _int_free (av, remainder, 1); | |
4757 | } | |
fa8d436c | 4758 | } |
f65fd747 | 4759 | |
6c8dbf00 OB |
4760 | check_inuse_chunk (av, p); |
4761 | return chunk2mem (p); | |
f65fd747 UD |
4762 | } |
4763 | ||
f65fd747 | 4764 | |
fa8d436c | 4765 | /* |
6c8dbf00 OB |
4766 | ------------------------------ malloc_trim ------------------------------ |
4767 | */ | |
8a4b65b4 | 4768 | |
6c8dbf00 OB |
4769 | static int |
4770 | mtrim (mstate av, size_t pad) | |
f65fd747 | 4771 | { |
3381be5c | 4772 | /* Ensure all blocks are consolidated. */ |
68631c8e UD |
4773 | malloc_consolidate (av); |
4774 | ||
6c8dbf00 | 4775 | const size_t ps = GLRO (dl_pagesize); |
68631c8e UD |
4776 | int psindex = bin_index (ps); |
4777 | const size_t psm1 = ps - 1; | |
4778 | ||
4779 | int result = 0; | |
4780 | for (int i = 1; i < NBINS; ++i) | |
4781 | if (i == 1 || i >= psindex) | |
4782 | { | |
6c8dbf00 | 4783 | mbinptr bin = bin_at (av, i); |
68631c8e | 4784 | |
6c8dbf00 OB |
4785 | for (mchunkptr p = last (bin); p != bin; p = p->bk) |
4786 | { | |
4787 | INTERNAL_SIZE_T size = chunksize (p); | |
68631c8e | 4788 | |
6c8dbf00 OB |
4789 | if (size > psm1 + sizeof (struct malloc_chunk)) |
4790 | { | |
4791 | /* See whether the chunk contains at least one unused page. */ | |
4792 | char *paligned_mem = (char *) (((uintptr_t) p | |
4793 | + sizeof (struct malloc_chunk) | |
4794 | + psm1) & ~psm1); | |
68631c8e | 4795 | |
6c8dbf00 OB |
4796 | assert ((char *) chunk2mem (p) + 4 * SIZE_SZ <= paligned_mem); |
4797 | assert ((char *) p + size > paligned_mem); | |
68631c8e | 4798 | |
6c8dbf00 OB |
4799 | /* This is the size we could potentially free. */ |
4800 | size -= paligned_mem - (char *) p; | |
68631c8e | 4801 | |
6c8dbf00 OB |
4802 | if (size > psm1) |
4803 | { | |
439bda32 | 4804 | #if MALLOC_DEBUG |
6c8dbf00 OB |
4805 | /* When debugging we simulate destroying the memory |
4806 | content. */ | |
4807 | memset (paligned_mem, 0x89, size & ~psm1); | |
68631c8e | 4808 | #endif |
6c8dbf00 | 4809 | __madvise (paligned_mem, size & ~psm1, MADV_DONTNEED); |
68631c8e | 4810 | |
6c8dbf00 OB |
4811 | result = 1; |
4812 | } | |
4813 | } | |
4814 | } | |
68631c8e | 4815 | } |
8a4b65b4 | 4816 | |
a9177ff5 | 4817 | #ifndef MORECORE_CANNOT_TRIM |
3b49edc0 | 4818 | return result | (av == &main_arena ? systrim (pad, av) : 0); |
6c8dbf00 | 4819 | |
8a4b65b4 | 4820 | #else |
68631c8e | 4821 | return result; |
f65fd747 | 4822 | #endif |
f65fd747 UD |
4823 | } |
4824 | ||
f65fd747 | 4825 | |
3b49edc0 | 4826 | int |
6c8dbf00 | 4827 | __malloc_trim (size_t s) |
3b49edc0 UD |
4828 | { |
4829 | int result = 0; | |
4830 | ||
6c8dbf00 | 4831 | if (__malloc_initialized < 0) |
3b49edc0 UD |
4832 | ptmalloc_init (); |
4833 | ||
4834 | mstate ar_ptr = &main_arena; | |
4835 | do | |
4836 | { | |
4bf5f222 | 4837 | __libc_lock_lock (ar_ptr->mutex); |
3b49edc0 | 4838 | result |= mtrim (ar_ptr, s); |
4bf5f222 | 4839 | __libc_lock_unlock (ar_ptr->mutex); |
3b49edc0 UD |
4840 | |
4841 | ar_ptr = ar_ptr->next; | |
4842 | } | |
4843 | while (ar_ptr != &main_arena); | |
4844 | ||
4845 | return result; | |
4846 | } | |
4847 | ||
4848 | ||
f65fd747 | 4849 | /* |
6c8dbf00 OB |
4850 | ------------------------- malloc_usable_size ------------------------- |
4851 | */ | |
f65fd747 | 4852 | |
3b49edc0 | 4853 | static size_t |
6c8dbf00 | 4854 | musable (void *mem) |
f65fd747 UD |
4855 | { |
4856 | mchunkptr p; | |
6c8dbf00 OB |
4857 | if (mem != 0) |
4858 | { | |
4859 | p = mem2chunk (mem); | |
4860 | ||
4861 | if (__builtin_expect (using_malloc_checking == 1, 0)) | |
4862 | return malloc_check_get_size (p); | |
4863 | ||
4864 | if (chunk_is_mmapped (p)) | |
073f8214 FW |
4865 | { |
4866 | if (DUMPED_MAIN_ARENA_CHUNK (p)) | |
4867 | return chunksize (p) - SIZE_SZ; | |
4868 | else | |
4869 | return chunksize (p) - 2 * SIZE_SZ; | |
4870 | } | |
6c8dbf00 OB |
4871 | else if (inuse (p)) |
4872 | return chunksize (p) - SIZE_SZ; | |
4873 | } | |
fa8d436c | 4874 | return 0; |
f65fd747 UD |
4875 | } |
4876 | ||
3b49edc0 UD |
4877 | |
4878 | size_t | |
6c8dbf00 | 4879 | __malloc_usable_size (void *m) |
3b49edc0 UD |
4880 | { |
4881 | size_t result; | |
4882 | ||
6c8dbf00 | 4883 | result = musable (m); |
3b49edc0 UD |
4884 | return result; |
4885 | } | |
4886 | ||
fa8d436c | 4887 | /* |
6c8dbf00 OB |
4888 | ------------------------------ mallinfo ------------------------------ |
4889 | Accumulate malloc statistics for arena AV into M. | |
4890 | */ | |
f65fd747 | 4891 | |
bedee953 | 4892 | static void |
6c8dbf00 | 4893 | int_mallinfo (mstate av, struct mallinfo *m) |
f65fd747 | 4894 | { |
6dd67bd5 | 4895 | size_t i; |
f65fd747 UD |
4896 | mbinptr b; |
4897 | mchunkptr p; | |
f65fd747 | 4898 | INTERNAL_SIZE_T avail; |
fa8d436c UD |
4899 | INTERNAL_SIZE_T fastavail; |
4900 | int nblocks; | |
4901 | int nfastblocks; | |
f65fd747 | 4902 | |
6c8dbf00 | 4903 | check_malloc_state (av); |
8a4b65b4 | 4904 | |
fa8d436c | 4905 | /* Account for top */ |
6c8dbf00 | 4906 | avail = chunksize (av->top); |
fa8d436c | 4907 | nblocks = 1; /* top always exists */ |
f65fd747 | 4908 | |
fa8d436c UD |
4909 | /* traverse fastbins */ |
4910 | nfastblocks = 0; | |
4911 | fastavail = 0; | |
4912 | ||
6c8dbf00 OB |
4913 | for (i = 0; i < NFASTBINS; ++i) |
4914 | { | |
4915 | for (p = fastbin (av, i); p != 0; p = p->fd) | |
4916 | { | |
4917 | ++nfastblocks; | |
4918 | fastavail += chunksize (p); | |
4919 | } | |
fa8d436c | 4920 | } |
fa8d436c UD |
4921 | |
4922 | avail += fastavail; | |
f65fd747 | 4923 | |
fa8d436c | 4924 | /* traverse regular bins */ |
6c8dbf00 OB |
4925 | for (i = 1; i < NBINS; ++i) |
4926 | { | |
4927 | b = bin_at (av, i); | |
4928 | for (p = last (b); p != b; p = p->bk) | |
4929 | { | |
4930 | ++nblocks; | |
4931 | avail += chunksize (p); | |
4932 | } | |
fa8d436c | 4933 | } |
f65fd747 | 4934 | |
bedee953 PP |
4935 | m->smblks += nfastblocks; |
4936 | m->ordblks += nblocks; | |
4937 | m->fordblks += avail; | |
4938 | m->uordblks += av->system_mem - avail; | |
4939 | m->arena += av->system_mem; | |
4940 | m->fsmblks += fastavail; | |
4941 | if (av == &main_arena) | |
4942 | { | |
4943 | m->hblks = mp_.n_mmaps; | |
4944 | m->hblkhd = mp_.mmapped_mem; | |
ca135f82 | 4945 | m->usmblks = 0; |
6c8dbf00 | 4946 | m->keepcost = chunksize (av->top); |
bedee953 | 4947 | } |
fa8d436c | 4948 | } |
f65fd747 | 4949 | |
3b49edc0 | 4950 | |
6c8dbf00 | 4951 | struct mallinfo |
9dd346ff | 4952 | __libc_mallinfo (void) |
3b49edc0 UD |
4953 | { |
4954 | struct mallinfo m; | |
bedee953 | 4955 | mstate ar_ptr; |
3b49edc0 | 4956 | |
6c8dbf00 | 4957 | if (__malloc_initialized < 0) |
3b49edc0 | 4958 | ptmalloc_init (); |
bedee953 | 4959 | |
6c8dbf00 | 4960 | memset (&m, 0, sizeof (m)); |
bedee953 | 4961 | ar_ptr = &main_arena; |
6c8dbf00 OB |
4962 | do |
4963 | { | |
4bf5f222 | 4964 | __libc_lock_lock (ar_ptr->mutex); |
6c8dbf00 | 4965 | int_mallinfo (ar_ptr, &m); |
4bf5f222 | 4966 | __libc_lock_unlock (ar_ptr->mutex); |
bedee953 | 4967 | |
6c8dbf00 OB |
4968 | ar_ptr = ar_ptr->next; |
4969 | } | |
4970 | while (ar_ptr != &main_arena); | |
bedee953 | 4971 | |
3b49edc0 UD |
4972 | return m; |
4973 | } | |
4974 | ||
fa8d436c | 4975 | /* |
6c8dbf00 OB |
4976 | ------------------------------ malloc_stats ------------------------------ |
4977 | */ | |
f65fd747 | 4978 | |
3b49edc0 | 4979 | void |
60d2f8f3 | 4980 | __malloc_stats (void) |
f65fd747 | 4981 | { |
8a4b65b4 | 4982 | int i; |
fa8d436c | 4983 | mstate ar_ptr; |
fa8d436c | 4984 | unsigned int in_use_b = mp_.mmapped_mem, system_b = in_use_b; |
8a4b65b4 | 4985 | |
6c8dbf00 | 4986 | if (__malloc_initialized < 0) |
a234e27d | 4987 | ptmalloc_init (); |
8dab36a1 | 4988 | _IO_flockfile (stderr); |
9964a145 ZW |
4989 | int old_flags2 = stderr->_flags2; |
4990 | stderr->_flags2 |= _IO_FLAGS2_NOTCANCEL; | |
6c8dbf00 OB |
4991 | for (i = 0, ar_ptr = &main_arena;; i++) |
4992 | { | |
4993 | struct mallinfo mi; | |
4994 | ||
4995 | memset (&mi, 0, sizeof (mi)); | |
4bf5f222 | 4996 | __libc_lock_lock (ar_ptr->mutex); |
6c8dbf00 OB |
4997 | int_mallinfo (ar_ptr, &mi); |
4998 | fprintf (stderr, "Arena %d:\n", i); | |
4999 | fprintf (stderr, "system bytes = %10u\n", (unsigned int) mi.arena); | |
5000 | fprintf (stderr, "in use bytes = %10u\n", (unsigned int) mi.uordblks); | |
fa8d436c | 5001 | #if MALLOC_DEBUG > 1 |
6c8dbf00 OB |
5002 | if (i > 0) |
5003 | dump_heap (heap_for_ptr (top (ar_ptr))); | |
fa8d436c | 5004 | #endif |
6c8dbf00 OB |
5005 | system_b += mi.arena; |
5006 | in_use_b += mi.uordblks; | |
4bf5f222 | 5007 | __libc_lock_unlock (ar_ptr->mutex); |
6c8dbf00 OB |
5008 | ar_ptr = ar_ptr->next; |
5009 | if (ar_ptr == &main_arena) | |
5010 | break; | |
5011 | } | |
5012 | fprintf (stderr, "Total (incl. mmap):\n"); | |
5013 | fprintf (stderr, "system bytes = %10u\n", system_b); | |
5014 | fprintf (stderr, "in use bytes = %10u\n", in_use_b); | |
5015 | fprintf (stderr, "max mmap regions = %10u\n", (unsigned int) mp_.max_n_mmaps); | |
5016 | fprintf (stderr, "max mmap bytes = %10lu\n", | |
5017 | (unsigned long) mp_.max_mmapped_mem); | |
9964a145 | 5018 | stderr->_flags2 = old_flags2; |
8dab36a1 | 5019 | _IO_funlockfile (stderr); |
f65fd747 UD |
5020 | } |
5021 | ||
f65fd747 UD |
5022 | |
5023 | /* | |
6c8dbf00 OB |
5024 | ------------------------------ mallopt ------------------------------ |
5025 | */ | |
be7991c0 SP |
5026 | static inline int |
5027 | __always_inline | |
5028 | do_set_trim_threshold (size_t value) | |
5029 | { | |
5030 | LIBC_PROBE (memory_mallopt_trim_threshold, 3, value, mp_.trim_threshold, | |
5031 | mp_.no_dyn_threshold); | |
5032 | mp_.trim_threshold = value; | |
5033 | mp_.no_dyn_threshold = 1; | |
5034 | return 1; | |
5035 | } | |
5036 | ||
5037 | static inline int | |
5038 | __always_inline | |
5039 | do_set_top_pad (size_t value) | |
5040 | { | |
5041 | LIBC_PROBE (memory_mallopt_top_pad, 3, value, mp_.top_pad, | |
5042 | mp_.no_dyn_threshold); | |
5043 | mp_.top_pad = value; | |
5044 | mp_.no_dyn_threshold = 1; | |
5045 | return 1; | |
5046 | } | |
5047 | ||
5048 | static inline int | |
5049 | __always_inline | |
5050 | do_set_mmap_threshold (size_t value) | |
5051 | { | |
5052 | /* Forbid setting the threshold too high. */ | |
5053 | if (value <= HEAP_MAX_SIZE / 2) | |
5054 | { | |
5055 | LIBC_PROBE (memory_mallopt_mmap_threshold, 3, value, mp_.mmap_threshold, | |
5056 | mp_.no_dyn_threshold); | |
5057 | mp_.mmap_threshold = value; | |
5058 | mp_.no_dyn_threshold = 1; | |
5059 | return 1; | |
5060 | } | |
5061 | return 0; | |
5062 | } | |
5063 | ||
5064 | static inline int | |
5065 | __always_inline | |
5066 | do_set_mmaps_max (int32_t value) | |
5067 | { | |
5068 | LIBC_PROBE (memory_mallopt_mmap_max, 3, value, mp_.n_mmaps_max, | |
5069 | mp_.no_dyn_threshold); | |
5070 | mp_.n_mmaps_max = value; | |
5071 | mp_.no_dyn_threshold = 1; | |
5072 | return 1; | |
5073 | } | |
5074 | ||
5075 | static inline int | |
5076 | __always_inline | |
5077 | do_set_mallopt_check (int32_t value) | |
5078 | { | |
be7991c0 SP |
5079 | return 1; |
5080 | } | |
5081 | ||
5082 | static inline int | |
5083 | __always_inline | |
5084 | do_set_perturb_byte (int32_t value) | |
5085 | { | |
5086 | LIBC_PROBE (memory_mallopt_perturb, 2, value, perturb_byte); | |
5087 | perturb_byte = value; | |
5088 | return 1; | |
5089 | } | |
5090 | ||
5091 | static inline int | |
5092 | __always_inline | |
5093 | do_set_arena_test (size_t value) | |
5094 | { | |
5095 | LIBC_PROBE (memory_mallopt_arena_test, 2, value, mp_.arena_test); | |
5096 | mp_.arena_test = value; | |
5097 | return 1; | |
5098 | } | |
5099 | ||
5100 | static inline int | |
5101 | __always_inline | |
5102 | do_set_arena_max (size_t value) | |
5103 | { | |
5104 | LIBC_PROBE (memory_mallopt_arena_max, 2, value, mp_.arena_max); | |
5105 | mp_.arena_max = value; | |
5106 | return 1; | |
5107 | } | |
5108 | ||
d5c3fafc DD |
5109 | #if USE_TCACHE |
5110 | static inline int | |
5111 | __always_inline | |
5112 | do_set_tcache_max (size_t value) | |
5113 | { | |
5114 | if (value >= 0 && value <= MAX_TCACHE_SIZE) | |
5115 | { | |
5116 | LIBC_PROBE (memory_tunable_tcache_max_bytes, 2, value, mp_.tcache_max_bytes); | |
5117 | mp_.tcache_max_bytes = value; | |
5118 | mp_.tcache_bins = csize2tidx (request2size(value)) + 1; | |
5119 | } | |
5120 | return 1; | |
5121 | } | |
5122 | ||
5123 | static inline int | |
5124 | __always_inline | |
5125 | do_set_tcache_count (size_t value) | |
5126 | { | |
95d66fec WD |
5127 | if (value <= MAX_TCACHE_COUNT) |
5128 | { | |
5129 | LIBC_PROBE (memory_tunable_tcache_count, 2, value, mp_.tcache_count); | |
5130 | mp_.tcache_count = value; | |
5131 | } | |
d5c3fafc DD |
5132 | return 1; |
5133 | } | |
5134 | ||
5135 | static inline int | |
5136 | __always_inline | |
5137 | do_set_tcache_unsorted_limit (size_t value) | |
5138 | { | |
5139 | LIBC_PROBE (memory_tunable_tcache_unsorted_limit, 2, value, mp_.tcache_unsorted_limit); | |
5140 | mp_.tcache_unsorted_limit = value; | |
5141 | return 1; | |
5142 | } | |
5143 | #endif | |
f65fd747 | 5144 | |
4618f1ff DD |
5145 | static inline int |
5146 | __always_inline | |
5147 | do_set_mxfast (size_t value) | |
5148 | { | |
5149 | if (value >= 0 && value <= MAX_FAST_SIZE) | |
5150 | { | |
5151 | LIBC_PROBE (memory_mallopt_mxfast, 2, value, get_max_fast ()); | |
5152 | set_max_fast (value); | |
5153 | return 1; | |
5154 | } | |
5155 | return 0; | |
5156 | } | |
5157 | ||
6c8dbf00 OB |
5158 | int |
5159 | __libc_mallopt (int param_number, int value) | |
f65fd747 | 5160 | { |
fa8d436c UD |
5161 | mstate av = &main_arena; |
5162 | int res = 1; | |
f65fd747 | 5163 | |
6c8dbf00 | 5164 | if (__malloc_initialized < 0) |
0cb71e02 | 5165 | ptmalloc_init (); |
4bf5f222 | 5166 | __libc_lock_lock (av->mutex); |
2f6d1f1b | 5167 | |
3ea5be54 AO |
5168 | LIBC_PROBE (memory_mallopt, 2, param_number, value); |
5169 | ||
3381be5c WD |
5170 | /* We must consolidate main arena before changing max_fast |
5171 | (see definition of set_max_fast). */ | |
5172 | malloc_consolidate (av); | |
5173 | ||
6c8dbf00 OB |
5174 | switch (param_number) |
5175 | { | |
5176 | case M_MXFAST: | |
4618f1ff | 5177 | do_set_mxfast (value); |
6c8dbf00 OB |
5178 | break; |
5179 | ||
5180 | case M_TRIM_THRESHOLD: | |
be7991c0 | 5181 | do_set_trim_threshold (value); |
6c8dbf00 OB |
5182 | break; |
5183 | ||
5184 | case M_TOP_PAD: | |
be7991c0 | 5185 | do_set_top_pad (value); |
6c8dbf00 OB |
5186 | break; |
5187 | ||
5188 | case M_MMAP_THRESHOLD: | |
be7991c0 | 5189 | res = do_set_mmap_threshold (value); |
6c8dbf00 OB |
5190 | break; |
5191 | ||
5192 | case M_MMAP_MAX: | |
be7991c0 | 5193 | do_set_mmaps_max (value); |
6c8dbf00 OB |
5194 | break; |
5195 | ||
5196 | case M_CHECK_ACTION: | |
be7991c0 | 5197 | do_set_mallopt_check (value); |
6c8dbf00 OB |
5198 | break; |
5199 | ||
5200 | case M_PERTURB: | |
be7991c0 | 5201 | do_set_perturb_byte (value); |
6c8dbf00 OB |
5202 | break; |
5203 | ||
5204 | case M_ARENA_TEST: | |
5205 | if (value > 0) | |
be7991c0 | 5206 | do_set_arena_test (value); |
6c8dbf00 OB |
5207 | break; |
5208 | ||
5209 | case M_ARENA_MAX: | |
5210 | if (value > 0) | |
62222284 | 5211 | do_set_arena_max (value); |
6c8dbf00 OB |
5212 | break; |
5213 | } | |
4bf5f222 | 5214 | __libc_lock_unlock (av->mutex); |
fa8d436c | 5215 | return res; |
b22fc5f5 | 5216 | } |
3b49edc0 | 5217 | libc_hidden_def (__libc_mallopt) |
b22fc5f5 | 5218 | |
10dc2a90 | 5219 | |
a9177ff5 | 5220 | /* |
6c8dbf00 OB |
5221 | -------------------- Alternative MORECORE functions -------------------- |
5222 | */ | |
10dc2a90 | 5223 | |
b22fc5f5 | 5224 | |
fa8d436c | 5225 | /* |
6c8dbf00 | 5226 | General Requirements for MORECORE. |
b22fc5f5 | 5227 | |
6c8dbf00 | 5228 | The MORECORE function must have the following properties: |
b22fc5f5 | 5229 | |
6c8dbf00 | 5230 | If MORECORE_CONTIGUOUS is false: |
10dc2a90 | 5231 | |
6c8dbf00 | 5232 | * MORECORE must allocate in multiples of pagesize. It will |
fa8d436c | 5233 | only be called with arguments that are multiples of pagesize. |
10dc2a90 | 5234 | |
6c8dbf00 | 5235 | * MORECORE(0) must return an address that is at least |
fa8d436c | 5236 | MALLOC_ALIGNMENT aligned. (Page-aligning always suffices.) |
10dc2a90 | 5237 | |
6c8dbf00 | 5238 | else (i.e. If MORECORE_CONTIGUOUS is true): |
10dc2a90 | 5239 | |
6c8dbf00 | 5240 | * Consecutive calls to MORECORE with positive arguments |
fa8d436c UD |
5241 | return increasing addresses, indicating that space has been |
5242 | contiguously extended. | |
10dc2a90 | 5243 | |
6c8dbf00 | 5244 | * MORECORE need not allocate in multiples of pagesize. |
fa8d436c | 5245 | Calls to MORECORE need not have args of multiples of pagesize. |
10dc2a90 | 5246 | |
6c8dbf00 | 5247 | * MORECORE need not page-align. |
10dc2a90 | 5248 | |
6c8dbf00 | 5249 | In either case: |
10dc2a90 | 5250 | |
6c8dbf00 | 5251 | * MORECORE may allocate more memory than requested. (Or even less, |
fa8d436c | 5252 | but this will generally result in a malloc failure.) |
10dc2a90 | 5253 | |
6c8dbf00 | 5254 | * MORECORE must not allocate memory when given argument zero, but |
fa8d436c UD |
5255 | instead return one past the end address of memory from previous |
5256 | nonzero call. This malloc does NOT call MORECORE(0) | |
5257 | until at least one call with positive arguments is made, so | |
5258 | the initial value returned is not important. | |
10dc2a90 | 5259 | |
6c8dbf00 | 5260 | * Even though consecutive calls to MORECORE need not return contiguous |
fa8d436c UD |
5261 | addresses, it must be OK for malloc'ed chunks to span multiple |
5262 | regions in those cases where they do happen to be contiguous. | |
10dc2a90 | 5263 | |
6c8dbf00 | 5264 | * MORECORE need not handle negative arguments -- it may instead |
fa8d436c UD |
5265 | just return MORECORE_FAILURE when given negative arguments. |
5266 | Negative arguments are always multiples of pagesize. MORECORE | |
5267 | must not misinterpret negative args as large positive unsigned | |
5268 | args. You can suppress all such calls from even occurring by defining | |
5269 | MORECORE_CANNOT_TRIM, | |
10dc2a90 | 5270 | |
6c8dbf00 OB |
5271 | There is some variation across systems about the type of the |
5272 | argument to sbrk/MORECORE. If size_t is unsigned, then it cannot | |
5273 | actually be size_t, because sbrk supports negative args, so it is | |
5274 | normally the signed type of the same width as size_t (sometimes | |
5275 | declared as "intptr_t", and sometimes "ptrdiff_t"). It doesn't much | |
5276 | matter though. Internally, we use "long" as arguments, which should | |
5277 | work across all reasonable possibilities. | |
5278 | ||
5279 | Additionally, if MORECORE ever returns failure for a positive | |
5280 | request, then mmap is used as a noncontiguous system allocator. This | |
5281 | is a useful backup strategy for systems with holes in address spaces | |
5282 | -- in this case sbrk cannot contiguously expand the heap, but mmap | |
5283 | may be able to map noncontiguous space. | |
5284 | ||
5285 | If you'd like mmap to ALWAYS be used, you can define MORECORE to be | |
5286 | a function that always returns MORECORE_FAILURE. | |
5287 | ||
5288 | If you are using this malloc with something other than sbrk (or its | |
5289 | emulation) to supply memory regions, you probably want to set | |
5290 | MORECORE_CONTIGUOUS as false. As an example, here is a custom | |
5291 | allocator kindly contributed for pre-OSX macOS. It uses virtually | |
5292 | but not necessarily physically contiguous non-paged memory (locked | |
5293 | in, present and won't get swapped out). You can use it by | |
5294 | uncommenting this section, adding some #includes, and setting up the | |
5295 | appropriate defines above: | |
5296 | ||
5297 | *#define MORECORE osMoreCore | |
5298 | *#define MORECORE_CONTIGUOUS 0 | |
5299 | ||
5300 | There is also a shutdown routine that should somehow be called for | |
5301 | cleanup upon program exit. | |
5302 | ||
5303 | *#define MAX_POOL_ENTRIES 100 | |
5304 | *#define MINIMUM_MORECORE_SIZE (64 * 1024) | |
5305 | static int next_os_pool; | |
5306 | void *our_os_pools[MAX_POOL_ENTRIES]; | |
5307 | ||
5308 | void *osMoreCore(int size) | |
5309 | { | |
fa8d436c UD |
5310 | void *ptr = 0; |
5311 | static void *sbrk_top = 0; | |
ca34d7a7 | 5312 | |
fa8d436c UD |
5313 | if (size > 0) |
5314 | { | |
5315 | if (size < MINIMUM_MORECORE_SIZE) | |
6c8dbf00 | 5316 | size = MINIMUM_MORECORE_SIZE; |
fa8d436c | 5317 | if (CurrentExecutionLevel() == kTaskLevel) |
6c8dbf00 | 5318 | ptr = PoolAllocateResident(size + RM_PAGE_SIZE, 0); |
fa8d436c UD |
5319 | if (ptr == 0) |
5320 | { | |
6c8dbf00 | 5321 | return (void *) MORECORE_FAILURE; |
fa8d436c UD |
5322 | } |
5323 | // save ptrs so they can be freed during cleanup | |
5324 | our_os_pools[next_os_pool] = ptr; | |
5325 | next_os_pool++; | |
5326 | ptr = (void *) ((((unsigned long) ptr) + RM_PAGE_MASK) & ~RM_PAGE_MASK); | |
5327 | sbrk_top = (char *) ptr + size; | |
5328 | return ptr; | |
5329 | } | |
5330 | else if (size < 0) | |
5331 | { | |
5332 | // we don't currently support shrink behavior | |
5333 | return (void *) MORECORE_FAILURE; | |
5334 | } | |
5335 | else | |
5336 | { | |
5337 | return sbrk_top; | |
431c33c0 | 5338 | } |
6c8dbf00 | 5339 | } |
ca34d7a7 | 5340 | |
6c8dbf00 OB |
5341 | // cleanup any allocated memory pools |
5342 | // called as last thing before shutting down driver | |
ca34d7a7 | 5343 | |
6c8dbf00 OB |
5344 | void osCleanupMem(void) |
5345 | { | |
fa8d436c | 5346 | void **ptr; |
ca34d7a7 | 5347 | |
fa8d436c UD |
5348 | for (ptr = our_os_pools; ptr < &our_os_pools[MAX_POOL_ENTRIES]; ptr++) |
5349 | if (*ptr) | |
5350 | { | |
6c8dbf00 OB |
5351 | PoolDeallocate(*ptr); |
5352 | * ptr = 0; | |
fa8d436c | 5353 | } |
6c8dbf00 | 5354 | } |
ee74a442 | 5355 | |
6c8dbf00 | 5356 | */ |
f65fd747 | 5357 | |
7e3be507 | 5358 | |
3e030bd5 UD |
5359 | /* Helper code. */ |
5360 | ||
ae7f5313 UD |
5361 | extern char **__libc_argv attribute_hidden; |
5362 | ||
3e030bd5 | 5363 | static void |
ac3ed168 | 5364 | malloc_printerr (const char *str) |
3e030bd5 | 5365 | { |
ec2c1fce FW |
5366 | __libc_message (do_abort, "%s\n", str); |
5367 | __builtin_unreachable (); | |
3e030bd5 UD |
5368 | } |
5369 | ||
a204dbb2 UD |
5370 | /* We need a wrapper function for one of the additions of POSIX. */ |
5371 | int | |
5372 | __posix_memalign (void **memptr, size_t alignment, size_t size) | |
5373 | { | |
5374 | void *mem; | |
5375 | ||
5376 | /* Test whether the SIZE argument is valid. It must be a power of | |
5377 | two multiple of sizeof (void *). */ | |
de02bd05 | 5378 | if (alignment % sizeof (void *) != 0 |
fc56e970 | 5379 | || !powerof2 (alignment / sizeof (void *)) |
de02bd05 | 5380 | || alignment == 0) |
a204dbb2 UD |
5381 | return EINVAL; |
5382 | ||
10ad46bc OB |
5383 | |
5384 | void *address = RETURN_ADDRESS (0); | |
5385 | mem = _mid_memalign (alignment, size, address); | |
a204dbb2 | 5386 | |
6c8dbf00 OB |
5387 | if (mem != NULL) |
5388 | { | |
5389 | *memptr = mem; | |
5390 | return 0; | |
5391 | } | |
a204dbb2 UD |
5392 | |
5393 | return ENOMEM; | |
5394 | } | |
5395 | weak_alias (__posix_memalign, posix_memalign) | |
5396 | ||
20c13899 OB |
5397 | |
5398 | int | |
c52ff39e | 5399 | __malloc_info (int options, FILE *fp) |
bb066545 | 5400 | { |
20c13899 OB |
5401 | /* For now, at least. */ |
5402 | if (options != 0) | |
5403 | return EINVAL; | |
bb066545 | 5404 | |
20c13899 OB |
5405 | int n = 0; |
5406 | size_t total_nblocks = 0; | |
5407 | size_t total_nfastblocks = 0; | |
5408 | size_t total_avail = 0; | |
5409 | size_t total_fastavail = 0; | |
5410 | size_t total_system = 0; | |
5411 | size_t total_max_system = 0; | |
5412 | size_t total_aspace = 0; | |
5413 | size_t total_aspace_mprotect = 0; | |
bb066545 | 5414 | |
6c8dbf00 | 5415 | |
6c8dbf00 | 5416 | |
987c0269 OB |
5417 | if (__malloc_initialized < 0) |
5418 | ptmalloc_init (); | |
bb066545 | 5419 | |
987c0269 | 5420 | fputs ("<malloc version=\"1\">\n", fp); |
bb066545 | 5421 | |
987c0269 OB |
5422 | /* Iterate over all arenas currently in use. */ |
5423 | mstate ar_ptr = &main_arena; | |
5424 | do | |
5425 | { | |
5426 | fprintf (fp, "<heap nr=\"%d\">\n<sizes>\n", n++); | |
8b35e35d | 5427 | |
987c0269 OB |
5428 | size_t nblocks = 0; |
5429 | size_t nfastblocks = 0; | |
5430 | size_t avail = 0; | |
5431 | size_t fastavail = 0; | |
5432 | struct | |
5433 | { | |
5434 | size_t from; | |
5435 | size_t to; | |
5436 | size_t total; | |
5437 | size_t count; | |
5438 | } sizes[NFASTBINS + NBINS - 1]; | |
5439 | #define nsizes (sizeof (sizes) / sizeof (sizes[0])) | |
6c8dbf00 | 5440 | |
4bf5f222 | 5441 | __libc_lock_lock (ar_ptr->mutex); |
bb066545 | 5442 | |
c6e4c319 NH |
5443 | /* Account for top chunk. The top-most available chunk is |
5444 | treated specially and is never in any bin. See "initial_top" | |
5445 | comments. */ | |
5446 | avail = chunksize (ar_ptr->top); | |
5447 | nblocks = 1; /* Top always exists. */ | |
5448 | ||
987c0269 OB |
5449 | for (size_t i = 0; i < NFASTBINS; ++i) |
5450 | { | |
5451 | mchunkptr p = fastbin (ar_ptr, i); | |
5452 | if (p != NULL) | |
5453 | { | |
5454 | size_t nthissize = 0; | |
5455 | size_t thissize = chunksize (p); | |
5456 | ||
5457 | while (p != NULL) | |
5458 | { | |
5459 | ++nthissize; | |
5460 | p = p->fd; | |
5461 | } | |
5462 | ||
5463 | fastavail += nthissize * thissize; | |
5464 | nfastblocks += nthissize; | |
5465 | sizes[i].from = thissize - (MALLOC_ALIGNMENT - 1); | |
5466 | sizes[i].to = thissize; | |
5467 | sizes[i].count = nthissize; | |
5468 | } | |
5469 | else | |
5470 | sizes[i].from = sizes[i].to = sizes[i].count = 0; | |
bb066545 | 5471 | |
987c0269 OB |
5472 | sizes[i].total = sizes[i].count * sizes[i].to; |
5473 | } | |
bb066545 | 5474 | |
bb066545 | 5475 | |
987c0269 OB |
5476 | mbinptr bin; |
5477 | struct malloc_chunk *r; | |
bb066545 | 5478 | |
987c0269 OB |
5479 | for (size_t i = 1; i < NBINS; ++i) |
5480 | { | |
5481 | bin = bin_at (ar_ptr, i); | |
5482 | r = bin->fd; | |
5483 | sizes[NFASTBINS - 1 + i].from = ~((size_t) 0); | |
5484 | sizes[NFASTBINS - 1 + i].to = sizes[NFASTBINS - 1 + i].total | |
5485 | = sizes[NFASTBINS - 1 + i].count = 0; | |
5486 | ||
5487 | if (r != NULL) | |
5488 | while (r != bin) | |
5489 | { | |
e9c4fe93 | 5490 | size_t r_size = chunksize_nomask (r); |
987c0269 | 5491 | ++sizes[NFASTBINS - 1 + i].count; |
e9c4fe93 | 5492 | sizes[NFASTBINS - 1 + i].total += r_size; |
987c0269 | 5493 | sizes[NFASTBINS - 1 + i].from |
e9c4fe93 | 5494 | = MIN (sizes[NFASTBINS - 1 + i].from, r_size); |
987c0269 | 5495 | sizes[NFASTBINS - 1 + i].to = MAX (sizes[NFASTBINS - 1 + i].to, |
e9c4fe93 | 5496 | r_size); |
987c0269 OB |
5497 | |
5498 | r = r->fd; | |
5499 | } | |
5500 | ||
5501 | if (sizes[NFASTBINS - 1 + i].count == 0) | |
5502 | sizes[NFASTBINS - 1 + i].from = 0; | |
5503 | nblocks += sizes[NFASTBINS - 1 + i].count; | |
5504 | avail += sizes[NFASTBINS - 1 + i].total; | |
5505 | } | |
bb066545 | 5506 | |
7a9368a1 FW |
5507 | size_t heap_size = 0; |
5508 | size_t heap_mprotect_size = 0; | |
34eb4157 | 5509 | size_t heap_count = 0; |
7a9368a1 FW |
5510 | if (ar_ptr != &main_arena) |
5511 | { | |
34eb4157 | 5512 | /* Iterate over the arena heaps from back to front. */ |
7a9368a1 | 5513 | heap_info *heap = heap_for_ptr (top (ar_ptr)); |
34eb4157 FW |
5514 | do |
5515 | { | |
5516 | heap_size += heap->size; | |
5517 | heap_mprotect_size += heap->mprotect_size; | |
5518 | heap = heap->prev; | |
5519 | ++heap_count; | |
5520 | } | |
5521 | while (heap != NULL); | |
7a9368a1 FW |
5522 | } |
5523 | ||
4bf5f222 | 5524 | __libc_lock_unlock (ar_ptr->mutex); |
da2d2fb6 | 5525 | |
987c0269 OB |
5526 | total_nfastblocks += nfastblocks; |
5527 | total_fastavail += fastavail; | |
0588a9cb | 5528 | |
987c0269 OB |
5529 | total_nblocks += nblocks; |
5530 | total_avail += avail; | |
0588a9cb | 5531 | |
987c0269 OB |
5532 | for (size_t i = 0; i < nsizes; ++i) |
5533 | if (sizes[i].count != 0 && i != NFASTBINS) | |
a0a551d2 | 5534 | fprintf (fp, "\ |
987c0269 OB |
5535 | <size from=\"%zu\" to=\"%zu\" total=\"%zu\" count=\"%zu\"/>\n", |
5536 | sizes[i].from, sizes[i].to, sizes[i].total, sizes[i].count); | |
fdfd175d | 5537 | |
987c0269 OB |
5538 | if (sizes[NFASTBINS].count != 0) |
5539 | fprintf (fp, "\ | |
5540 | <unsorted from=\"%zu\" to=\"%zu\" total=\"%zu\" count=\"%zu\"/>\n", | |
5541 | sizes[NFASTBINS].from, sizes[NFASTBINS].to, | |
5542 | sizes[NFASTBINS].total, sizes[NFASTBINS].count); | |
fdfd175d | 5543 | |
987c0269 OB |
5544 | total_system += ar_ptr->system_mem; |
5545 | total_max_system += ar_ptr->max_system_mem; | |
bb066545 | 5546 | |
987c0269 OB |
5547 | fprintf (fp, |
5548 | "</sizes>\n<total type=\"fast\" count=\"%zu\" size=\"%zu\"/>\n" | |
5549 | "<total type=\"rest\" count=\"%zu\" size=\"%zu\"/>\n" | |
5550 | "<system type=\"current\" size=\"%zu\"/>\n" | |
5551 | "<system type=\"max\" size=\"%zu\"/>\n", | |
5552 | nfastblocks, fastavail, nblocks, avail, | |
5553 | ar_ptr->system_mem, ar_ptr->max_system_mem); | |
346bc35c | 5554 | |
987c0269 OB |
5555 | if (ar_ptr != &main_arena) |
5556 | { | |
987c0269 OB |
5557 | fprintf (fp, |
5558 | "<aspace type=\"total\" size=\"%zu\"/>\n" | |
34eb4157 FW |
5559 | "<aspace type=\"mprotect\" size=\"%zu\"/>\n" |
5560 | "<aspace type=\"subheaps\" size=\"%zu\"/>\n", | |
5561 | heap_size, heap_mprotect_size, heap_count); | |
7a9368a1 FW |
5562 | total_aspace += heap_size; |
5563 | total_aspace_mprotect += heap_mprotect_size; | |
987c0269 OB |
5564 | } |
5565 | else | |
5566 | { | |
5567 | fprintf (fp, | |
5568 | "<aspace type=\"total\" size=\"%zu\"/>\n" | |
5569 | "<aspace type=\"mprotect\" size=\"%zu\"/>\n", | |
5570 | ar_ptr->system_mem, ar_ptr->system_mem); | |
5571 | total_aspace += ar_ptr->system_mem; | |
5572 | total_aspace_mprotect += ar_ptr->system_mem; | |
5573 | } | |
bb066545 | 5574 | |
987c0269 | 5575 | fputs ("</heap>\n", fp); |
bb066545 UD |
5576 | ar_ptr = ar_ptr->next; |
5577 | } | |
5578 | while (ar_ptr != &main_arena); | |
5579 | ||
5580 | fprintf (fp, | |
62a58816 SP |
5581 | "<total type=\"fast\" count=\"%zu\" size=\"%zu\"/>\n" |
5582 | "<total type=\"rest\" count=\"%zu\" size=\"%zu\"/>\n" | |
9fa76613 | 5583 | "<total type=\"mmap\" count=\"%d\" size=\"%zu\"/>\n" |
62a58816 SP |
5584 | "<system type=\"current\" size=\"%zu\"/>\n" |
5585 | "<system type=\"max\" size=\"%zu\"/>\n" | |
5586 | "<aspace type=\"total\" size=\"%zu\"/>\n" | |
5587 | "<aspace type=\"mprotect\" size=\"%zu\"/>\n" | |
5588 | "</malloc>\n", | |
5589 | total_nfastblocks, total_fastavail, total_nblocks, total_avail, | |
4d653a59 | 5590 | mp_.n_mmaps, mp_.mmapped_mem, |
62a58816 SP |
5591 | total_system, total_max_system, |
5592 | total_aspace, total_aspace_mprotect); | |
bb066545 UD |
5593 | |
5594 | return 0; | |
5595 | } | |
c52ff39e | 5596 | weak_alias (__malloc_info, malloc_info) |
bb066545 UD |
5597 | |
5598 | ||
eba19d2b | 5599 | strong_alias (__libc_calloc, __calloc) weak_alias (__libc_calloc, calloc) |
eba19d2b UD |
5600 | strong_alias (__libc_free, __free) strong_alias (__libc_free, free) |
5601 | strong_alias (__libc_malloc, __malloc) strong_alias (__libc_malloc, malloc) | |
5602 | strong_alias (__libc_memalign, __memalign) | |
5603 | weak_alias (__libc_memalign, memalign) | |
5604 | strong_alias (__libc_realloc, __realloc) strong_alias (__libc_realloc, realloc) | |
5605 | strong_alias (__libc_valloc, __valloc) weak_alias (__libc_valloc, valloc) | |
5606 | strong_alias (__libc_pvalloc, __pvalloc) weak_alias (__libc_pvalloc, pvalloc) | |
5607 | strong_alias (__libc_mallinfo, __mallinfo) | |
5608 | weak_alias (__libc_mallinfo, mallinfo) | |
5609 | strong_alias (__libc_mallopt, __mallopt) weak_alias (__libc_mallopt, mallopt) | |
7e3be507 UD |
5610 | |
5611 | weak_alias (__malloc_stats, malloc_stats) | |
5612 | weak_alias (__malloc_usable_size, malloc_usable_size) | |
5613 | weak_alias (__malloc_trim, malloc_trim) | |
7e3be507 | 5614 | |
025b33ae FW |
5615 | #if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_26) |
5616 | compat_symbol (libc, __libc_free, cfree, GLIBC_2_0); | |
5617 | #endif | |
f65fd747 | 5618 | |
fa8d436c | 5619 | /* ------------------------------------------------------------ |
6c8dbf00 | 5620 | History: |
f65fd747 | 5621 | |
6c8dbf00 | 5622 | [see ftp://g.oswego.edu/pub/misc/malloc.c for the history of dlmalloc] |
f65fd747 | 5623 | |
6c8dbf00 | 5624 | */ |
fa8d436c UD |
5625 | /* |
5626 | * Local variables: | |
5627 | * c-basic-offset: 2 | |
5628 | * End: | |
5629 | */ |