1 | #include <assert.h>
|
---|
2 | #include <limits.h>
|
---|
3 | #include <stddef.h>
|
---|
4 | #include <stdio.h>
|
---|
5 | #include <stdlib.h>
|
---|
6 | #include <string.h>
|
---|
7 | #include "syssvc/syslog.h"
|
---|
8 |
|
---|
9 | #include "tlsf.h"
|
---|
10 |
|
---|
11 | #undef _MSC_VER
|
---|
12 |
|
---|
13 | #if defined(__cplusplus)
|
---|
14 | #define tlsf_decl inline
|
---|
15 | #else
|
---|
16 | #define tlsf_decl static
|
---|
17 | #endif
|
---|
18 |
|
---|
19 | /*
|
---|
20 | ** Architecture-specific bit manipulation routines.
|
---|
21 | **
|
---|
22 | ** TLSF achieves O(1) cost for malloc and free operations by limiting
|
---|
23 | ** the search for a free block to a free list of guaranteed size
|
---|
24 | ** adequate to fulfill the request, combined with efficient free list
|
---|
25 | ** queries using bitmasks and architecture-specific bit-manipulation
|
---|
26 | ** routines.
|
---|
27 | **
|
---|
28 | ** Most modern processors provide instructions to count leading zeroes
|
---|
29 | ** in a word, find the lowest and highest set bit, etc. These
|
---|
30 | ** specific implementations will be used when available, falling back
|
---|
31 | ** to a reasonably efficient generic implementation.
|
---|
32 | **
|
---|
33 | ** NOTE: TLSF spec relies on ffs/fls returning value 0..31.
|
---|
34 | ** ffs/fls return 1-32 by default, returning 0 for error.
|
---|
35 | */
|
---|
36 |
|
---|
37 | /*
|
---|
38 | ** Detect whether or not we are building for a 32- or 64-bit (LP/LLP)
|
---|
39 | ** architecture. There is no reliable portable method at compile-time.
|
---|
40 | */
|
---|
41 | #if defined (__alpha__) || defined (__ia64__) || defined (__x86_64__) \
|
---|
42 | || defined (_WIN64) || defined (__LP64__) || defined (__LLP64__)
|
---|
43 | #define TLSF_64BIT
|
---|
44 | #endif
|
---|
45 |
|
---|
46 | /*
|
---|
47 | ** gcc 3.4 and above have builtin support, specialized for architecture.
|
---|
48 | ** Some compilers masquerade as gcc; patchlevel test filters them out.
|
---|
49 | */
|
---|
50 | #if defined (__GNUC__) && (__GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4)) \
|
---|
51 | && defined (__GNUC_PATCHLEVEL__)
|
---|
52 |
|
---|
53 | #if defined (__SNC__)
|
---|
54 | /* SNC for Playstation 3. */
|
---|
55 |
|
---|
56 | tlsf_decl int tlsf_ffs(unsigned int word)
|
---|
57 | {
|
---|
58 | const unsigned int reverse = word & (~word + 1);
|
---|
59 | const int bit = 32 - __builtin_clz(reverse);
|
---|
60 | return bit - 1;
|
---|
61 | }
|
---|
62 |
|
---|
63 | #else
|
---|
64 |
|
---|
65 | tlsf_decl int tlsf_ffs(unsigned int word)
|
---|
66 | {
|
---|
67 | return __builtin_ffs(word) - 1;
|
---|
68 | }
|
---|
69 |
|
---|
70 | #endif
|
---|
71 |
|
---|
72 | tlsf_decl int tlsf_fls(unsigned int word)
|
---|
73 | {
|
---|
74 | const int bit = word ? 32 - __builtin_clz(word) : 0;
|
---|
75 | return bit - 1;
|
---|
76 | }
|
---|
77 |
|
---|
78 | #elif defined (_MSC_VER) && (_MSC_VER >= 1400) && (defined (_M_IX86) || defined (_M_X64))
|
---|
79 | /* Microsoft Visual C++ support on x86/X64 architectures. */
|
---|
80 |
|
---|
81 | #include <intrin.h>
|
---|
82 |
|
---|
83 | #pragma intrinsic(_BitScanReverse)
|
---|
84 | #pragma intrinsic(_BitScanForward)
|
---|
85 |
|
---|
86 | tlsf_decl int tlsf_fls(unsigned int word)
|
---|
87 | {
|
---|
88 | unsigned long index;
|
---|
89 | return _BitScanReverse(&index, word) ? index : -1;
|
---|
90 | }
|
---|
91 |
|
---|
92 | tlsf_decl int tlsf_ffs(unsigned int word)
|
---|
93 | {
|
---|
94 | unsigned long index;
|
---|
95 | return _BitScanForward(&index, word) ? index : -1;
|
---|
96 | }
|
---|
97 |
|
---|
98 | #elif defined (_MSC_VER) && defined (_M_PPC)
|
---|
99 | /* Microsoft Visual C++ support on PowerPC architectures. */
|
---|
100 |
|
---|
101 | #include <ppcintrinsics.h>
|
---|
102 |
|
---|
103 | tlsf_decl int tlsf_fls(unsigned int word)
|
---|
104 | {
|
---|
105 | const int bit = 32 - _CountLeadingZeros(word);
|
---|
106 | return bit - 1;
|
---|
107 | }
|
---|
108 |
|
---|
109 | tlsf_decl int tlsf_ffs(unsigned int word)
|
---|
110 | {
|
---|
111 | const unsigned int reverse = word & (~word + 1);
|
---|
112 | const int bit = 32 - _CountLeadingZeros(reverse);
|
---|
113 | return bit - 1;
|
---|
114 | }
|
---|
115 |
|
---|
116 | #elif defined (__ARMCC_VERSION)
|
---|
117 | /* RealView Compilation Tools for ARM */
|
---|
118 |
|
---|
119 | tlsf_decl int tlsf_ffs(unsigned int word)
|
---|
120 | {
|
---|
121 | const unsigned int reverse = word & (~word + 1);
|
---|
122 | const int bit = 32 - __clz(reverse);
|
---|
123 | return bit - 1;
|
---|
124 | }
|
---|
125 |
|
---|
126 | tlsf_decl int tlsf_fls(unsigned int word)
|
---|
127 | {
|
---|
128 | const int bit = word ? 32 - __clz(word) : 0;
|
---|
129 | return bit - 1;
|
---|
130 | }
|
---|
131 |
|
---|
132 | #elif defined (__ghs__)
|
---|
133 | /* Green Hills support for PowerPC */
|
---|
134 |
|
---|
135 | #include <ppc_ghs.h>
|
---|
136 |
|
---|
137 | tlsf_decl int tlsf_ffs(unsigned int word)
|
---|
138 | {
|
---|
139 | const unsigned int reverse = word & (~word + 1);
|
---|
140 | const int bit = 32 - __CLZ32(reverse);
|
---|
141 | return bit - 1;
|
---|
142 | }
|
---|
143 |
|
---|
144 | tlsf_decl int tlsf_fls(unsigned int word)
|
---|
145 | {
|
---|
146 | const int bit = word ? 32 - __CLZ32(word) : 0;
|
---|
147 | return bit - 1;
|
---|
148 | }
|
---|
149 |
|
---|
150 | #else
|
---|
151 | /* Fall back to generic implementation. */
|
---|
152 |
|
---|
153 | tlsf_decl int tlsf_fls_generic(unsigned int word)
|
---|
154 | {
|
---|
155 | int bit = 32;
|
---|
156 |
|
---|
157 | if (!word) bit -= 1;
|
---|
158 | if (!(word & 0xffff0000)) { word <<= 16; bit -= 16; }
|
---|
159 | if (!(word & 0xff000000)) { word <<= 8; bit -= 8; }
|
---|
160 | if (!(word & 0xf0000000)) { word <<= 4; bit -= 4; }
|
---|
161 | if (!(word & 0xc0000000)) { word <<= 2; bit -= 2; }
|
---|
162 | if (!(word & 0x80000000)) { word <<= 1; bit -= 1; }
|
---|
163 |
|
---|
164 | return bit;
|
---|
165 | }
|
---|
166 |
|
---|
167 | /* Implement ffs in terms of fls. */
|
---|
168 | tlsf_decl int tlsf_ffs(unsigned int word)
|
---|
169 | {
|
---|
170 | return tlsf_fls_generic(word & (~word + 1)) - 1;
|
---|
171 | }
|
---|
172 |
|
---|
173 | tlsf_decl int tlsf_fls(unsigned int word)
|
---|
174 | {
|
---|
175 | return tlsf_fls_generic(word) - 1;
|
---|
176 | }
|
---|
177 |
|
---|
178 | #endif
|
---|
179 |
|
---|
180 | /* Possibly 64-bit version of tlsf_fls. */
|
---|
181 | #if defined (TLSF_64BIT)
|
---|
182 | tlsf_decl int tlsf_fls_sizet(size_t size)
|
---|
183 | {
|
---|
184 | int high = (int)(size >> 32);
|
---|
185 | int bits = 0;
|
---|
186 | if (high)
|
---|
187 | {
|
---|
188 | bits = 32 + tlsf_fls(high);
|
---|
189 | }
|
---|
190 | else
|
---|
191 | {
|
---|
192 | bits = tlsf_fls((int)size & 0xffffffff);
|
---|
193 |
|
---|
194 | }
|
---|
195 | return bits;
|
---|
196 | }
|
---|
197 | #else
|
---|
198 | #define tlsf_fls_sizet tlsf_fls
|
---|
199 | #endif
|
---|
200 |
|
---|
201 | #undef tlsf_decl
|
---|
202 |
|
---|
203 | /*
|
---|
204 | ** Constants.
|
---|
205 | */
|
---|
206 |
|
---|
207 | /* Public constants: may be modified. */
|
---|
208 | enum tlsf_public
|
---|
209 | {
|
---|
210 | /* log2 of number of linear subdivisions of block sizes. Larger
|
---|
211 | ** values require more memory in the control structure. Values of
|
---|
212 | ** 4 or 5 are typical.
|
---|
213 | */
|
---|
214 | SL_INDEX_COUNT_LOG2 = 5,
|
---|
215 | };
|
---|
216 |
|
---|
217 | /* Private constants: do not modify. */
|
---|
218 | enum tlsf_private
|
---|
219 | {
|
---|
220 | #if defined (TLSF_64BIT)
|
---|
221 | /* All allocation sizes and addresses are aligned to 8 bytes. */
|
---|
222 | ALIGN_SIZE_LOG2 = 3,
|
---|
223 | #else
|
---|
224 | /* All allocation sizes and addresses are aligned to 4 bytes. */
|
---|
225 | ALIGN_SIZE_LOG2 = 2,
|
---|
226 | #endif
|
---|
227 | ALIGN_SIZE = (1 << ALIGN_SIZE_LOG2),
|
---|
228 |
|
---|
229 | /*
|
---|
230 | ** We support allocations of sizes up to (1 << FL_INDEX_MAX) bits.
|
---|
231 | ** However, because we linearly subdivide the second-level lists, and
|
---|
232 | ** our minimum size granularity is 4 bytes, it doesn't make sense to
|
---|
233 | ** create first-level lists for sizes smaller than SL_INDEX_COUNT * 4,
|
---|
234 | ** or (1 << (SL_INDEX_COUNT_LOG2 + 2)) bytes, as there we will be
|
---|
235 | ** trying to split size ranges into more slots than we have available.
|
---|
236 | ** Instead, we calculate the minimum threshold size, and place all
|
---|
237 | ** blocks below that size into the 0th first-level list.
|
---|
238 | */
|
---|
239 |
|
---|
240 | #if defined (TLSF_64BIT)
|
---|
241 | /*
|
---|
242 | ** TODO: We can increase this to support larger sizes, at the expense
|
---|
243 | ** of more overhead in the TLSF structure.
|
---|
244 | */
|
---|
245 | FL_INDEX_MAX = 32,
|
---|
246 | #else
|
---|
247 | FL_INDEX_MAX = 30,
|
---|
248 | #endif
|
---|
249 | SL_INDEX_COUNT = (1 << SL_INDEX_COUNT_LOG2),
|
---|
250 | FL_INDEX_SHIFT = (SL_INDEX_COUNT_LOG2 + ALIGN_SIZE_LOG2),
|
---|
251 | FL_INDEX_COUNT = (FL_INDEX_MAX - FL_INDEX_SHIFT + 1),
|
---|
252 |
|
---|
253 | SMALL_BLOCK_SIZE = (1 << FL_INDEX_SHIFT),
|
---|
254 | };
|
---|
255 |
|
---|
256 | /*
|
---|
257 | ** Cast and min/max macros.
|
---|
258 | */
|
---|
259 |
|
---|
260 | #define tlsf_cast(t, exp) ((t) (exp))
|
---|
261 | #define tlsf_min(a, b) ((a) < (b) ? (a) : (b))
|
---|
262 | #define tlsf_max(a, b) ((a) > (b) ? (a) : (b))
|
---|
263 |
|
---|
264 | /*
|
---|
265 | ** Set assert macro, if it has not been provided by the user.
|
---|
266 | */
|
---|
267 | #if !defined (tlsf_assert)
|
---|
268 | #define tlsf_assert assert
|
---|
269 | #endif
|
---|
270 |
|
---|
271 | /*
|
---|
272 | ** Static assertion mechanism.
|
---|
273 | */
|
---|
274 |
|
---|
275 | #define _tlsf_glue2(x, y) x ## y
|
---|
276 | #define _tlsf_glue(x, y) _tlsf_glue2(x, y)
|
---|
277 | #define tlsf_static_assert(exp) \
|
---|
278 | typedef char _tlsf_glue(static_assert, __LINE__) [(exp) ? 1 : -1]
|
---|
279 |
|
---|
280 | /* This code has been tested on 32- and 64-bit (LP/LLP) architectures. */
|
---|
281 | tlsf_static_assert(sizeof(int) * CHAR_BIT == 32);
|
---|
282 | tlsf_static_assert(sizeof(size_t) * CHAR_BIT >= 32);
|
---|
283 | tlsf_static_assert(sizeof(size_t) * CHAR_BIT <= 64);
|
---|
284 |
|
---|
285 | /* SL_INDEX_COUNT must be <= number of bits in sl_bitmap's storage type. */
|
---|
286 | tlsf_static_assert(sizeof(unsigned int) * CHAR_BIT >= SL_INDEX_COUNT);
|
---|
287 |
|
---|
288 | /* Ensure we've properly tuned our sizes. */
|
---|
289 | tlsf_static_assert(ALIGN_SIZE == SMALL_BLOCK_SIZE / SL_INDEX_COUNT);
|
---|
290 |
|
---|
291 | /*
|
---|
292 | ** Data structures and associated constants.
|
---|
293 | */
|
---|
294 |
|
---|
295 | /*
|
---|
296 | ** Block header structure.
|
---|
297 | **
|
---|
298 | ** There are several implementation subtleties involved:
|
---|
299 | ** - The prev_phys_block field is only valid if the previous block is free.
|
---|
300 | ** - The prev_phys_block field is actually stored at the end of the
|
---|
301 | ** previous block. It appears at the beginning of this structure only to
|
---|
302 | ** simplify the implementation.
|
---|
303 | ** - The next_free / prev_free fields are only valid if the block is free.
|
---|
304 | */
|
---|
305 | typedef struct block_header_t
|
---|
306 | {
|
---|
307 | /* Points to the previous physical block. */
|
---|
308 | struct block_header_t* prev_phys_block;
|
---|
309 |
|
---|
310 | /* The size of this block, excluding the block header. */
|
---|
311 | size_t size;
|
---|
312 |
|
---|
313 | /* Next and previous free blocks. */
|
---|
314 | struct block_header_t* next_free;
|
---|
315 | struct block_header_t* prev_free;
|
---|
316 | } block_header_t;
|
---|
317 |
|
---|
318 | /*
|
---|
319 | ** Since block sizes are always at least a multiple of 4, the two least
|
---|
320 | ** significant bits of the size field are used to store the block status:
|
---|
321 | ** - bit 0: whether block is busy or free
|
---|
322 | ** - bit 1: whether previous block is busy or free
|
---|
323 | */
|
---|
324 | static const size_t block_header_free_bit = 1 << 0;
|
---|
325 | static const size_t block_header_prev_free_bit = 1 << 1;
|
---|
326 |
|
---|
327 | /*
|
---|
328 | ** The size of the block header exposed to used blocks is the size field.
|
---|
329 | ** The prev_phys_block field is stored *inside* the previous free block.
|
---|
330 | */
|
---|
331 | static const size_t block_header_overhead = sizeof(size_t);
|
---|
332 |
|
---|
333 | /* User data starts directly after the size field in a used block. */
|
---|
334 | static const size_t block_start_offset =
|
---|
335 | offsetof(block_header_t, size) + sizeof(size_t);
|
---|
336 |
|
---|
337 | /*
|
---|
338 | ** A free block must be large enough to store its header minus the size of
|
---|
339 | ** the prev_phys_block field, and no larger than the number of addressable
|
---|
340 | ** bits for FL_INDEX.
|
---|
341 | */
|
---|
342 | static const size_t block_size_min =
|
---|
343 | sizeof(block_header_t) - sizeof(block_header_t*);
|
---|
344 | static const size_t block_size_max = tlsf_cast(size_t, 1) << FL_INDEX_MAX;
|
---|
345 |
|
---|
346 |
|
---|
347 | /* The TLSF control structure. */
|
---|
348 | typedef struct control_t
|
---|
349 | {
|
---|
350 | /* Empty lists point at this block to indicate they are free. */
|
---|
351 | block_header_t block_null;
|
---|
352 |
|
---|
353 | /* Bitmaps for free lists. */
|
---|
354 | unsigned int fl_bitmap;
|
---|
355 | unsigned int sl_bitmap[FL_INDEX_COUNT];
|
---|
356 |
|
---|
357 | /* Head of free lists. */
|
---|
358 | block_header_t* blocks[FL_INDEX_COUNT][SL_INDEX_COUNT];
|
---|
359 | } control_t;
|
---|
360 |
|
---|
361 | /* A type used for casting when doing pointer arithmetic. */
|
---|
362 | typedef ptrdiff_t tlsfptr_t;
|
---|
363 |
|
---|
364 | /*
|
---|
365 | ** block_header_t member functions.
|
---|
366 | */
|
---|
367 |
|
---|
368 | static size_t block_size(const block_header_t* block)
|
---|
369 | {
|
---|
370 | return block->size & ~(block_header_free_bit | block_header_prev_free_bit);
|
---|
371 | }
|
---|
372 |
|
---|
373 | static void block_set_size(block_header_t* block, size_t size)
|
---|
374 | {
|
---|
375 | const size_t oldsize = block->size;
|
---|
376 | block->size = size | (oldsize & (block_header_free_bit | block_header_prev_free_bit));
|
---|
377 | }
|
---|
378 |
|
---|
379 | static int block_is_last(const block_header_t* block)
|
---|
380 | {
|
---|
381 | return block_size(block) == 0;
|
---|
382 | }
|
---|
383 |
|
---|
384 | static int block_is_free(const block_header_t* block)
|
---|
385 | {
|
---|
386 | return tlsf_cast(int, block->size & block_header_free_bit);
|
---|
387 | }
|
---|
388 |
|
---|
389 | static void block_set_free(block_header_t* block)
|
---|
390 | {
|
---|
391 | block->size |= block_header_free_bit;
|
---|
392 | }
|
---|
393 |
|
---|
394 | static void block_set_used(block_header_t* block)
|
---|
395 | {
|
---|
396 | block->size &= ~block_header_free_bit;
|
---|
397 | }
|
---|
398 |
|
---|
399 | static int block_is_prev_free(const block_header_t* block)
|
---|
400 | {
|
---|
401 | return tlsf_cast(int, block->size & block_header_prev_free_bit);
|
---|
402 | }
|
---|
403 |
|
---|
404 | static void block_set_prev_free(block_header_t* block)
|
---|
405 | {
|
---|
406 | block->size |= block_header_prev_free_bit;
|
---|
407 | }
|
---|
408 |
|
---|
409 | static void block_set_prev_used(block_header_t* block)
|
---|
410 | {
|
---|
411 | block->size &= ~block_header_prev_free_bit;
|
---|
412 | }
|
---|
413 |
|
---|
414 | static block_header_t* block_from_ptr(const void* ptr)
|
---|
415 | {
|
---|
416 | return tlsf_cast(block_header_t*,
|
---|
417 | tlsf_cast(unsigned char*, ptr) - block_start_offset);
|
---|
418 | }
|
---|
419 |
|
---|
420 | static void* block_to_ptr(const block_header_t* block)
|
---|
421 | {
|
---|
422 | return tlsf_cast(void*,
|
---|
423 | tlsf_cast(unsigned char*, block) + block_start_offset);
|
---|
424 | }
|
---|
425 |
|
---|
426 | /* Return location of next block after block of given size. */
|
---|
427 | static block_header_t* offset_to_block(const void* ptr, size_t size)
|
---|
428 | {
|
---|
429 | return tlsf_cast(block_header_t*, tlsf_cast(tlsfptr_t, ptr) + size);
|
---|
430 | }
|
---|
431 |
|
---|
432 | /* Return location of previous block. */
|
---|
433 | static block_header_t* block_prev(const block_header_t* block)
|
---|
434 | {
|
---|
435 | tlsf_assert(block_is_prev_free(block) && "previous block must be free");
|
---|
436 | return block->prev_phys_block;
|
---|
437 | }
|
---|
438 |
|
---|
439 | /* Return location of next existing block. */
|
---|
440 | static block_header_t* block_next(const block_header_t* block)
|
---|
441 | {
|
---|
442 | block_header_t* next = offset_to_block(block_to_ptr(block),
|
---|
443 | block_size(block) - block_header_overhead);
|
---|
444 | tlsf_assert(!block_is_last(block));
|
---|
445 | return next;
|
---|
446 | }
|
---|
447 |
|
---|
448 | /* Link a new block with its physical neighbor, return the neighbor. */
|
---|
449 | static block_header_t* block_link_next(block_header_t* block)
|
---|
450 | {
|
---|
451 | block_header_t* next = block_next(block);
|
---|
452 | next->prev_phys_block = block;
|
---|
453 | return next;
|
---|
454 | }
|
---|
455 |
|
---|
456 | static void block_mark_as_free(block_header_t* block)
|
---|
457 | {
|
---|
458 | /* Link the block to the next block, first. */
|
---|
459 | block_header_t* next = block_link_next(block);
|
---|
460 | block_set_prev_free(next);
|
---|
461 | block_set_free(block);
|
---|
462 | }
|
---|
463 |
|
---|
464 | static void block_mark_as_used(block_header_t* block)
|
---|
465 | {
|
---|
466 | block_header_t* next = block_next(block);
|
---|
467 | block_set_prev_used(next);
|
---|
468 | block_set_used(block);
|
---|
469 | }
|
---|
470 |
|
---|
471 | static size_t align_up(size_t x, size_t align)
|
---|
472 | {
|
---|
473 | tlsf_assert(0 == (align & (align - 1)) && "must align to a power of two");
|
---|
474 | return (x + (align - 1)) & ~(align - 1);
|
---|
475 | }
|
---|
476 |
|
---|
477 | static size_t align_down(size_t x, size_t align)
|
---|
478 | {
|
---|
479 | tlsf_assert(0 == (align & (align - 1)) && "must align to a power of two");
|
---|
480 | return x - (x & (align - 1));
|
---|
481 | }
|
---|
482 |
|
---|
483 | static void* align_ptr(const void* ptr, size_t align)
|
---|
484 | {
|
---|
485 | const tlsfptr_t aligned =
|
---|
486 | (tlsf_cast(tlsfptr_t, ptr) + (align - 1)) & ~(align - 1);
|
---|
487 | tlsf_assert(0 == (align & (align - 1)) && "must align to a power of two");
|
---|
488 | return tlsf_cast(void*, aligned);
|
---|
489 | }
|
---|
490 |
|
---|
491 | /*
|
---|
492 | ** Adjust an allocation size to be aligned to word size, and no smaller
|
---|
493 | ** than internal minimum.
|
---|
494 | */
|
---|
495 | static size_t adjust_request_size(size_t size, size_t align)
|
---|
496 | {
|
---|
497 | size_t adjust = 0;
|
---|
498 | if (size && size < block_size_max)
|
---|
499 | {
|
---|
500 | const size_t aligned = align_up(size, align);
|
---|
501 | adjust = tlsf_max(aligned, block_size_min);
|
---|
502 | }
|
---|
503 | return adjust;
|
---|
504 | }
|
---|
505 |
|
---|
506 | /*
|
---|
507 | ** TLSF utility functions. In most cases, these are direct translations of
|
---|
508 | ** the documentation found in the white paper.
|
---|
509 | */
|
---|
510 |
|
---|
511 | static void mapping_insert(size_t size, int* fli, int* sli)
|
---|
512 | {
|
---|
513 | int fl, sl;
|
---|
514 | if (size < SMALL_BLOCK_SIZE)
|
---|
515 | {
|
---|
516 | /* Store small blocks in first list. */
|
---|
517 | fl = 0;
|
---|
518 | sl = tlsf_cast(int, size) / (SMALL_BLOCK_SIZE / SL_INDEX_COUNT);
|
---|
519 | }
|
---|
520 | else
|
---|
521 | {
|
---|
522 | fl = tlsf_fls_sizet(size);
|
---|
523 | sl = tlsf_cast(int, size >> (fl - SL_INDEX_COUNT_LOG2)) ^ (1 << SL_INDEX_COUNT_LOG2);
|
---|
524 | fl -= (FL_INDEX_SHIFT - 1);
|
---|
525 | }
|
---|
526 | *fli = fl;
|
---|
527 | *sli = sl;
|
---|
528 | }
|
---|
529 |
|
---|
530 | /* This version rounds up to the next block size (for allocations) */
|
---|
531 | static void mapping_search(size_t size, int* fli, int* sli)
|
---|
532 | {
|
---|
533 | if (size >= SMALL_BLOCK_SIZE)
|
---|
534 | {
|
---|
535 | const size_t round = (1 << (tlsf_fls_sizet(size) - SL_INDEX_COUNT_LOG2)) - 1;
|
---|
536 | size += round;
|
---|
537 | }
|
---|
538 | mapping_insert(size, fli, sli);
|
---|
539 | }
|
---|
540 |
|
---|
541 | static block_header_t* search_suitable_block(control_t* control, int* fli, int* sli)
|
---|
542 | {
|
---|
543 | int fl = *fli;
|
---|
544 | int sl = *sli;
|
---|
545 |
|
---|
546 | /*
|
---|
547 | ** First, search for a block in the list associated with the given
|
---|
548 | ** fl/sl index.
|
---|
549 | */
|
---|
550 | unsigned int sl_map = control->sl_bitmap[fl] & (~0U << sl);
|
---|
551 | if (!sl_map)
|
---|
552 | {
|
---|
553 | /* No block exists. Search in the next largest first-level list. */
|
---|
554 | const unsigned int fl_map = control->fl_bitmap & (~0U << (fl + 1));
|
---|
555 | if (!fl_map)
|
---|
556 | {
|
---|
557 | /* No free blocks available, memory has been exhausted. */
|
---|
558 | return 0;
|
---|
559 | }
|
---|
560 |
|
---|
561 | fl = tlsf_ffs(fl_map);
|
---|
562 | *fli = fl;
|
---|
563 | sl_map = control->sl_bitmap[fl];
|
---|
564 | }
|
---|
565 | tlsf_assert(sl_map && "internal error - second level bitmap is null");
|
---|
566 | sl = tlsf_ffs(sl_map);
|
---|
567 | *sli = sl;
|
---|
568 |
|
---|
569 | /* Return the first block in the free list. */
|
---|
570 | return control->blocks[fl][sl];
|
---|
571 | }
|
---|
572 |
|
---|
573 | /* Remove a free block from the free list.*/
|
---|
574 | static void remove_free_block(control_t* control, block_header_t* block, int fl, int sl)
|
---|
575 | {
|
---|
576 | block_header_t* prev = block->prev_free;
|
---|
577 | block_header_t* next = block->next_free;
|
---|
578 | tlsf_assert(prev && "prev_free field can not be null");
|
---|
579 | tlsf_assert(next && "next_free field can not be null");
|
---|
580 | next->prev_free = prev;
|
---|
581 | prev->next_free = next;
|
---|
582 |
|
---|
583 | /* If this block is the head of the free list, set new head. */
|
---|
584 | if (control->blocks[fl][sl] == block)
|
---|
585 | {
|
---|
586 | control->blocks[fl][sl] = next;
|
---|
587 |
|
---|
588 | /* If the new head is null, clear the bitmap. */
|
---|
589 | if (next == &control->block_null)
|
---|
590 | {
|
---|
591 | control->sl_bitmap[fl] &= ~(1 << sl);
|
---|
592 |
|
---|
593 | /* If the second bitmap is now empty, clear the fl bitmap. */
|
---|
594 | if (!control->sl_bitmap[fl])
|
---|
595 | {
|
---|
596 | control->fl_bitmap &= ~(1 << fl);
|
---|
597 | }
|
---|
598 | }
|
---|
599 | }
|
---|
600 | }
|
---|
601 |
|
---|
602 | /* Insert a free block into the free block list. */
|
---|
603 | static void insert_free_block(control_t* control, block_header_t* block, int fl, int sl)
|
---|
604 | {
|
---|
605 | block_header_t* current = control->blocks[fl][sl];
|
---|
606 | tlsf_assert(current && "free list cannot have a null entry");
|
---|
607 | tlsf_assert(block && "cannot insert a null entry into the free list");
|
---|
608 | block->next_free = current;
|
---|
609 | block->prev_free = &control->block_null;
|
---|
610 | current->prev_free = block;
|
---|
611 |
|
---|
612 | tlsf_assert(block_to_ptr(block) == align_ptr(block_to_ptr(block), ALIGN_SIZE)
|
---|
613 | && "block not aligned properly");
|
---|
614 | /*
|
---|
615 | ** Insert the new block at the head of the list, and mark the first-
|
---|
616 | ** and second-level bitmaps appropriately.
|
---|
617 | */
|
---|
618 | control->blocks[fl][sl] = block;
|
---|
619 | control->fl_bitmap |= (1 << fl);
|
---|
620 | control->sl_bitmap[fl] |= (1 << sl);
|
---|
621 | }
|
---|
622 |
|
---|
623 | /* Remove a given block from the free list. */
|
---|
624 | static void block_remove(control_t* control, block_header_t* block)
|
---|
625 | {
|
---|
626 | int fl, sl;
|
---|
627 | mapping_insert(block_size(block), &fl, &sl);
|
---|
628 | remove_free_block(control, block, fl, sl);
|
---|
629 | }
|
---|
630 |
|
---|
631 | /* Insert a given block into the free list. */
|
---|
632 | static void block_insert(control_t* control, block_header_t* block)
|
---|
633 | {
|
---|
634 | int fl, sl;
|
---|
635 | mapping_insert(block_size(block), &fl, &sl);
|
---|
636 | insert_free_block(control, block, fl, sl);
|
---|
637 | }
|
---|
638 |
|
---|
639 | static int block_can_split(block_header_t* block, size_t size)
|
---|
640 | {
|
---|
641 | return block_size(block) >= sizeof(block_header_t) + size;
|
---|
642 | }
|
---|
643 |
|
---|
644 | /* Split a block into two, the second of which is free. */
|
---|
645 | static block_header_t* block_split(block_header_t* block, size_t size)
|
---|
646 | {
|
---|
647 | /* Calculate the amount of space left in the remaining block. */
|
---|
648 | block_header_t* remaining =
|
---|
649 | offset_to_block(block_to_ptr(block), size - block_header_overhead);
|
---|
650 |
|
---|
651 | const size_t remain_size = block_size(block) - (size + block_header_overhead);
|
---|
652 |
|
---|
653 | tlsf_assert(block_to_ptr(remaining) == align_ptr(block_to_ptr(remaining), ALIGN_SIZE)
|
---|
654 | && "remaining block not aligned properly");
|
---|
655 |
|
---|
656 | tlsf_assert(block_size(block) == remain_size + size + block_header_overhead);
|
---|
657 | block_set_size(remaining, remain_size);
|
---|
658 | tlsf_assert(block_size(remaining) >= block_size_min && "block split with invalid size");
|
---|
659 |
|
---|
660 | block_set_size(block, size);
|
---|
661 | block_mark_as_free(remaining);
|
---|
662 |
|
---|
663 | return remaining;
|
---|
664 | }
|
---|
665 |
|
---|
666 | /* Absorb a free block's storage into an adjacent previous free block. */
|
---|
667 | static block_header_t* block_absorb(block_header_t* prev, block_header_t* block)
|
---|
668 | {
|
---|
669 | tlsf_assert(!block_is_last(prev) && "previous block can't be last");
|
---|
670 | /* Note: Leaves flags untouched. */
|
---|
671 | prev->size += block_size(block) + block_header_overhead;
|
---|
672 | block_link_next(prev);
|
---|
673 | return prev;
|
---|
674 | }
|
---|
675 |
|
---|
676 | /* Merge a just-freed block with an adjacent previous free block. */
|
---|
677 | static block_header_t* block_merge_prev(control_t* control, block_header_t* block)
|
---|
678 | {
|
---|
679 | if (block_is_prev_free(block))
|
---|
680 | {
|
---|
681 | block_header_t* prev = block_prev(block);
|
---|
682 | tlsf_assert(prev && "prev physical block can't be null");
|
---|
683 | tlsf_assert(block_is_free(prev) && "prev block is not free though marked as such");
|
---|
684 | block_remove(control, prev);
|
---|
685 | block = block_absorb(prev, block);
|
---|
686 | }
|
---|
687 |
|
---|
688 | return block;
|
---|
689 | }
|
---|
690 |
|
---|
691 | /* Merge a just-freed block with an adjacent free block. */
|
---|
692 | static block_header_t* block_merge_next(control_t* control, block_header_t* block)
|
---|
693 | {
|
---|
694 | block_header_t* next = block_next(block);
|
---|
695 | tlsf_assert(next && "next physical block can't be null");
|
---|
696 |
|
---|
697 | if (block_is_free(next))
|
---|
698 | {
|
---|
699 | tlsf_assert(!block_is_last(block) && "previous block can't be last");
|
---|
700 | block_remove(control, next);
|
---|
701 | block = block_absorb(block, next);
|
---|
702 | }
|
---|
703 |
|
---|
704 | return block;
|
---|
705 | }
|
---|
706 |
|
---|
707 | /* Trim any trailing block space off the end of a block, return to pool. */
|
---|
708 | static void block_trim_free(control_t* control, block_header_t* block, size_t size)
|
---|
709 | {
|
---|
710 | tlsf_assert(block_is_free(block) && "block must be free");
|
---|
711 | if (block_can_split(block, size))
|
---|
712 | {
|
---|
713 | block_header_t* remaining_block = block_split(block, size);
|
---|
714 | block_link_next(block);
|
---|
715 | block_set_prev_free(remaining_block);
|
---|
716 | block_insert(control, remaining_block);
|
---|
717 | }
|
---|
718 | }
|
---|
719 |
|
---|
720 | /* Trim any trailing block space off the end of a used block, return to pool. */
|
---|
721 | static void block_trim_used(control_t* control, block_header_t* block, size_t size)
|
---|
722 | {
|
---|
723 | tlsf_assert(!block_is_free(block) && "block must be used");
|
---|
724 | if (block_can_split(block, size))
|
---|
725 | {
|
---|
726 | /* If the next block is free, we must coalesce. */
|
---|
727 | block_header_t* remaining_block = block_split(block, size);
|
---|
728 | block_set_prev_used(remaining_block);
|
---|
729 |
|
---|
730 | remaining_block = block_merge_next(control, remaining_block);
|
---|
731 | block_insert(control, remaining_block);
|
---|
732 | }
|
---|
733 | }
|
---|
734 |
|
---|
735 | static block_header_t* block_trim_free_leading(control_t* control, block_header_t* block, size_t size)
|
---|
736 | {
|
---|
737 | block_header_t* remaining_block = block;
|
---|
738 | if (block_can_split(block, size))
|
---|
739 | {
|
---|
740 | /* We want the 2nd block. */
|
---|
741 | remaining_block = block_split(block, size - block_header_overhead);
|
---|
742 | block_set_prev_free(remaining_block);
|
---|
743 |
|
---|
744 | block_link_next(block);
|
---|
745 | block_insert(control, block);
|
---|
746 | }
|
---|
747 |
|
---|
748 | return remaining_block;
|
---|
749 | }
|
---|
750 |
|
---|
751 | static block_header_t* block_locate_free(control_t* control, size_t size)
|
---|
752 | {
|
---|
753 | int fl = 0, sl = 0;
|
---|
754 | block_header_t* block = 0;
|
---|
755 |
|
---|
756 | if (size)
|
---|
757 | {
|
---|
758 | mapping_search(size, &fl, &sl);
|
---|
759 | block = search_suitable_block(control, &fl, &sl);
|
---|
760 | }
|
---|
761 |
|
---|
762 | if (block)
|
---|
763 | {
|
---|
764 | tlsf_assert(block_size(block) >= size);
|
---|
765 | remove_free_block(control, block, fl, sl);
|
---|
766 | }
|
---|
767 |
|
---|
768 | return block;
|
---|
769 | }
|
---|
770 |
|
---|
771 | static void* block_prepare_used(control_t* control, block_header_t* block, size_t size)
|
---|
772 | {
|
---|
773 | void* p = 0;
|
---|
774 | if (block)
|
---|
775 | {
|
---|
776 | tlsf_assert(size && "size must be non-zero");
|
---|
777 | block_trim_free(control, block, size);
|
---|
778 | block_mark_as_used(block);
|
---|
779 | p = block_to_ptr(block);
|
---|
780 | }
|
---|
781 | return p;
|
---|
782 | }
|
---|
783 |
|
---|
784 | /* Clear structure and point all empty lists at the null block. */
|
---|
785 | static void control_construct(control_t* control)
|
---|
786 | {
|
---|
787 | int i, j;
|
---|
788 |
|
---|
789 | control->block_null.next_free = &control->block_null;
|
---|
790 | control->block_null.prev_free = &control->block_null;
|
---|
791 |
|
---|
792 | control->fl_bitmap = 0;
|
---|
793 | for (i = 0; i < FL_INDEX_COUNT; ++i)
|
---|
794 | {
|
---|
795 | control->sl_bitmap[i] = 0;
|
---|
796 | for (j = 0; j < SL_INDEX_COUNT; ++j)
|
---|
797 | {
|
---|
798 | control->blocks[i][j] = &control->block_null;
|
---|
799 | }
|
---|
800 | }
|
---|
801 | }
|
---|
802 |
|
---|
803 | /*
|
---|
804 | ** Debugging utilities.
|
---|
805 | */
|
---|
806 |
|
---|
807 | typedef struct integrity_t
|
---|
808 | {
|
---|
809 | int prev_status;
|
---|
810 | int status;
|
---|
811 | } integrity_t;
|
---|
812 |
|
---|
813 | #define tlsf_insist(x) { tlsf_assert(x); if (!(x)) { status--; } }
|
---|
814 |
|
---|
815 | static void integrity_walker(void* ptr, size_t size, int used, void* user)
|
---|
816 | {
|
---|
817 | block_header_t* block = block_from_ptr(ptr);
|
---|
818 | integrity_t* integ = tlsf_cast(integrity_t*, user);
|
---|
819 | const int this_prev_status = block_is_prev_free(block) ? 1 : 0;
|
---|
820 | const int this_status = block_is_free(block) ? 1 : 0;
|
---|
821 | const size_t this_block_size = block_size(block);
|
---|
822 |
|
---|
823 | int status = 0;
|
---|
824 | (void)used;
|
---|
825 | tlsf_insist(integ->prev_status == this_prev_status && "prev status incorrect");
|
---|
826 | tlsf_insist(size == this_block_size && "block size incorrect");
|
---|
827 |
|
---|
828 | integ->prev_status = this_status;
|
---|
829 | integ->status += status;
|
---|
830 | }
|
---|
831 |
|
---|
832 | int tlsf_check(tlsf_t tlsf)
|
---|
833 | {
|
---|
834 | int i, j;
|
---|
835 |
|
---|
836 | control_t* control = tlsf_cast(control_t*, tlsf);
|
---|
837 | int status = 0;
|
---|
838 |
|
---|
839 | /* Check that the free lists and bitmaps are accurate. */
|
---|
840 | for (i = 0; i < FL_INDEX_COUNT; ++i)
|
---|
841 | {
|
---|
842 | for (j = 0; j < SL_INDEX_COUNT; ++j)
|
---|
843 | {
|
---|
844 | const int fl_map = control->fl_bitmap & (1 << i);
|
---|
845 | const int sl_list = control->sl_bitmap[i];
|
---|
846 | const int sl_map = sl_list & (1 << j);
|
---|
847 | const block_header_t* block = control->blocks[i][j];
|
---|
848 |
|
---|
849 | /* Check that first- and second-level lists agree. */
|
---|
850 | if (!fl_map)
|
---|
851 | {
|
---|
852 | tlsf_insist(!sl_map && "second-level map must be null");
|
---|
853 | }
|
---|
854 |
|
---|
855 | if (!sl_map)
|
---|
856 | {
|
---|
857 | tlsf_insist(block == &control->block_null && "block list must be null");
|
---|
858 | continue;
|
---|
859 | }
|
---|
860 |
|
---|
861 | /* Check that there is at least one free block. */
|
---|
862 | tlsf_insist(sl_list && "no free blocks in second-level map");
|
---|
863 | tlsf_insist(block != &control->block_null && "block should not be null");
|
---|
864 |
|
---|
865 | while (block != &control->block_null)
|
---|
866 | {
|
---|
867 | int fli, sli;
|
---|
868 | tlsf_insist(block_is_free(block) && "block should be free");
|
---|
869 | tlsf_insist(!block_is_prev_free(block) && "blocks should have coalesced");
|
---|
870 | tlsf_insist(!block_is_free(block_next(block)) && "blocks should have coalesced");
|
---|
871 | tlsf_insist(block_is_prev_free(block_next(block)) && "block should be free");
|
---|
872 | tlsf_insist(block_size(block) >= block_size_min && "block not minimum size");
|
---|
873 |
|
---|
874 | mapping_insert(block_size(block), &fli, &sli);
|
---|
875 | tlsf_insist(fli == i && sli == j && "block size indexed in wrong list");
|
---|
876 | block = block->next_free;
|
---|
877 | }
|
---|
878 | }
|
---|
879 | }
|
---|
880 |
|
---|
881 | return status;
|
---|
882 | }
|
---|
883 |
|
---|
884 | #undef tlsf_insist
|
---|
885 |
|
---|
886 | static void default_walker(void* ptr, size_t size, int used, void* user)
|
---|
887 | {
|
---|
888 | (void)user;
|
---|
889 | syslog(LOG_INFO, "\t%p %s size: %x (%p)\n", ptr, used ? "used" : "free", (unsigned int)size, block_from_ptr(ptr));
|
---|
890 | }
|
---|
891 |
|
---|
892 | void tlsf_walk_pool(pool_t pool, tlsf_walker walker, void* user)
|
---|
893 | {
|
---|
894 | tlsf_walker pool_walker = walker ? walker : default_walker;
|
---|
895 | block_header_t* block =
|
---|
896 | offset_to_block(pool, -(int)block_header_overhead);
|
---|
897 |
|
---|
898 | while (block && !block_is_last(block))
|
---|
899 | {
|
---|
900 | pool_walker(
|
---|
901 | block_to_ptr(block),
|
---|
902 | block_size(block),
|
---|
903 | !block_is_free(block),
|
---|
904 | user);
|
---|
905 | block = block_next(block);
|
---|
906 | }
|
---|
907 | }
|
---|
908 |
|
---|
909 | size_t tlsf_block_size(void* ptr)
|
---|
910 | {
|
---|
911 | size_t size = 0;
|
---|
912 | if (ptr)
|
---|
913 | {
|
---|
914 | const block_header_t* block = block_from_ptr(ptr);
|
---|
915 | size = block_size(block);
|
---|
916 | }
|
---|
917 | return size;
|
---|
918 | }
|
---|
919 |
|
---|
920 | int tlsf_check_pool(pool_t pool)
|
---|
921 | {
|
---|
922 | /* Check that the blocks are physically correct. */
|
---|
923 | integrity_t integ = { 0, 0 };
|
---|
924 | tlsf_walk_pool(pool, integrity_walker, &integ);
|
---|
925 |
|
---|
926 | return integ.status;
|
---|
927 | }
|
---|
928 |
|
---|
929 | /*
|
---|
930 | ** Size of the TLSF structures in a given memory block passed to
|
---|
931 | ** tlsf_create, equal to the size of a control_t
|
---|
932 | */
|
---|
933 | size_t tlsf_size(void)
|
---|
934 | {
|
---|
935 | return sizeof(control_t);
|
---|
936 | }
|
---|
937 |
|
---|
938 | size_t tlsf_align_size(void)
|
---|
939 | {
|
---|
940 | return ALIGN_SIZE;
|
---|
941 | }
|
---|
942 |
|
---|
943 | size_t tlsf_block_size_min(void)
|
---|
944 | {
|
---|
945 | return block_size_min;
|
---|
946 | }
|
---|
947 |
|
---|
948 | size_t tlsf_block_size_max(void)
|
---|
949 | {
|
---|
950 | return block_size_max;
|
---|
951 | }
|
---|
952 |
|
---|
953 | /*
|
---|
954 | ** Overhead of the TLSF structures in a given memory block passed to
|
---|
955 | ** tlsf_add_pool, equal to the overhead of a free block and the
|
---|
956 | ** sentinel block.
|
---|
957 | */
|
---|
958 | size_t tlsf_pool_overhead(void)
|
---|
959 | {
|
---|
960 | return 2 * block_header_overhead;
|
---|
961 | }
|
---|
962 |
|
---|
963 | size_t tlsf_alloc_overhead(void)
|
---|
964 | {
|
---|
965 | return block_header_overhead;
|
---|
966 | }
|
---|
967 |
|
---|
968 | pool_t tlsf_add_pool(tlsf_t tlsf, void* mem, size_t bytes)
|
---|
969 | {
|
---|
970 | block_header_t* block;
|
---|
971 | block_header_t* next;
|
---|
972 |
|
---|
973 | const size_t pool_overhead = tlsf_pool_overhead();
|
---|
974 | const size_t pool_bytes = align_down(bytes - pool_overhead, ALIGN_SIZE);
|
---|
975 |
|
---|
976 | if (((ptrdiff_t)mem % ALIGN_SIZE) != 0)
|
---|
977 | {
|
---|
978 | syslog(LOG_INFO, "tlsf_add_pool: Memory must be aligned by %u bytes.\n",
|
---|
979 | (unsigned int)ALIGN_SIZE);
|
---|
980 | return 0;
|
---|
981 | }
|
---|
982 |
|
---|
983 | if (pool_bytes < block_size_min || pool_bytes > block_size_max)
|
---|
984 | {
|
---|
985 | #if defined (TLSF_64BIT)
|
---|
986 | syslog(LOG_INFO, "tlsf_add_pool: Memory size must be between 0x%x and 0x%x00 bytes.\n",
|
---|
987 | (unsigned int)(pool_overhead + block_size_min),
|
---|
988 | (unsigned int)((pool_overhead + block_size_max) / 256));
|
---|
989 | #else
|
---|
990 | syslog(LOG_INFO, "tlsf_add_pool: Memory size must be between %u and %u bytes.\n",
|
---|
991 | (unsigned int)(pool_overhead + block_size_min),
|
---|
992 | (unsigned int)(pool_overhead + block_size_max));
|
---|
993 | #endif
|
---|
994 | return 0;
|
---|
995 | }
|
---|
996 |
|
---|
997 | /*
|
---|
998 | ** Create the main free block. Offset the start of the block slightly
|
---|
999 | ** so that the prev_phys_block field falls outside of the pool -
|
---|
1000 | ** it will never be used.
|
---|
1001 | */
|
---|
1002 | block = offset_to_block(mem, -(tlsfptr_t)block_header_overhead);
|
---|
1003 | block_set_size(block, pool_bytes);
|
---|
1004 | block_set_free(block);
|
---|
1005 | block_set_prev_used(block);
|
---|
1006 | block_insert(tlsf_cast(control_t*, tlsf), block);
|
---|
1007 |
|
---|
1008 | /* Split the block to create a zero-size sentinel block. */
|
---|
1009 | next = block_link_next(block);
|
---|
1010 | block_set_size(next, 0);
|
---|
1011 | block_set_used(next);
|
---|
1012 | block_set_prev_free(next);
|
---|
1013 |
|
---|
1014 | return mem;
|
---|
1015 | }
|
---|
1016 |
|
---|
1017 | void tlsf_remove_pool(tlsf_t tlsf, pool_t pool)
|
---|
1018 | {
|
---|
1019 | control_t* control = tlsf_cast(control_t*, tlsf);
|
---|
1020 | block_header_t* block = offset_to_block(pool, -(int)block_header_overhead);
|
---|
1021 |
|
---|
1022 | int fl = 0, sl = 0;
|
---|
1023 |
|
---|
1024 | tlsf_assert(block_is_free(block) && "block should be free");
|
---|
1025 | tlsf_assert(!block_is_free(block_next(block)) && "next block should not be free");
|
---|
1026 | tlsf_assert(block_size(block_next(block)) == 0 && "next block size should be zero");
|
---|
1027 |
|
---|
1028 | mapping_insert(block_size(block), &fl, &sl);
|
---|
1029 | remove_free_block(control, block, fl, sl);
|
---|
1030 | }
|
---|
1031 |
|
---|
1032 | /*
|
---|
1033 | ** TLSF main interface.
|
---|
1034 | */
|
---|
1035 |
|
---|
1036 | #if _DEBUG
|
---|
1037 | int test_ffs_fls()
|
---|
1038 | {
|
---|
1039 | /* Verify ffs/fls work properly. */
|
---|
1040 | int rv = 0;
|
---|
1041 | rv += (tlsf_ffs(0) == -1) ? 0 : 0x1;
|
---|
1042 | rv += (tlsf_fls(0) == -1) ? 0 : 0x2;
|
---|
1043 | rv += (tlsf_ffs(1) == 0) ? 0 : 0x4;
|
---|
1044 | rv += (tlsf_fls(1) == 0) ? 0 : 0x8;
|
---|
1045 | rv += (tlsf_ffs(0x80000000) == 31) ? 0 : 0x10;
|
---|
1046 | rv += (tlsf_ffs(0x80008000) == 15) ? 0 : 0x20;
|
---|
1047 | rv += (tlsf_fls(0x80000008) == 31) ? 0 : 0x40;
|
---|
1048 | rv += (tlsf_fls(0x7FFFFFFF) == 30) ? 0 : 0x80;
|
---|
1049 |
|
---|
1050 | #if defined (TLSF_64BIT)
|
---|
1051 | rv += (tlsf_fls_sizet(0x80000000) == 31) ? 0 : 0x100;
|
---|
1052 | rv += (tlsf_fls_sizet(0x100000000) == 32) ? 0 : 0x200;
|
---|
1053 | rv += (tlsf_fls_sizet(0xffffffffffffffff) == 63) ? 0 : 0x400;
|
---|
1054 | #endif
|
---|
1055 |
|
---|
1056 | if (rv)
|
---|
1057 | {
|
---|
1058 | syslog(LOG_INFO, "test_ffs_fls: %x ffs/fls tests failed.\n", rv);
|
---|
1059 | }
|
---|
1060 | return rv;
|
---|
1061 | }
|
---|
1062 | #endif
|
---|
1063 |
|
---|
1064 | tlsf_t tlsf_create(void* mem)
|
---|
1065 | {
|
---|
1066 | #if _DEBUG
|
---|
1067 | if (test_ffs_fls())
|
---|
1068 | {
|
---|
1069 | return 0;
|
---|
1070 | }
|
---|
1071 | #endif
|
---|
1072 |
|
---|
1073 | if (((tlsfptr_t)mem % ALIGN_SIZE) != 0)
|
---|
1074 | {
|
---|
1075 | syslog(LOG_INFO, "tlsf_create: Memory must be aligned to %u bytes.\n",
|
---|
1076 | (unsigned int)ALIGN_SIZE);
|
---|
1077 | return 0;
|
---|
1078 | }
|
---|
1079 |
|
---|
1080 | control_construct(tlsf_cast(control_t*, mem));
|
---|
1081 |
|
---|
1082 | return tlsf_cast(tlsf_t, mem);
|
---|
1083 | }
|
---|
1084 |
|
---|
1085 | tlsf_t tlsf_create_with_pool(void* mem, size_t bytes)
|
---|
1086 | {
|
---|
1087 | tlsf_t tlsf = tlsf_create(mem);
|
---|
1088 | tlsf_add_pool(tlsf, (char*)mem + tlsf_size(), bytes - tlsf_size());
|
---|
1089 | return tlsf;
|
---|
1090 | }
|
---|
1091 |
|
---|
1092 | void tlsf_destroy(tlsf_t tlsf)
|
---|
1093 | {
|
---|
1094 | /* Nothing to do. */
|
---|
1095 | (void)tlsf;
|
---|
1096 | }
|
---|
1097 |
|
---|
1098 | pool_t tlsf_get_pool(tlsf_t tlsf)
|
---|
1099 | {
|
---|
1100 | return tlsf_cast(pool_t, (char*)tlsf + tlsf_size());
|
---|
1101 | }
|
---|
1102 |
|
---|
1103 | void* tlsf_malloc(tlsf_t tlsf, size_t size)
|
---|
1104 | {
|
---|
1105 | control_t* control = tlsf_cast(control_t*, tlsf);
|
---|
1106 | const size_t adjust = adjust_request_size(size, ALIGN_SIZE);
|
---|
1107 | block_header_t* block = block_locate_free(control, adjust);
|
---|
1108 | return block_prepare_used(control, block, adjust);
|
---|
1109 | }
|
---|
1110 |
|
---|
1111 | void* tlsf_memalign(tlsf_t tlsf, size_t align, size_t size)
|
---|
1112 | {
|
---|
1113 | control_t* control = tlsf_cast(control_t*, tlsf);
|
---|
1114 | const size_t adjust = adjust_request_size(size, ALIGN_SIZE);
|
---|
1115 |
|
---|
1116 | /*
|
---|
1117 | ** We must allocate an additional minimum block size bytes so that if
|
---|
1118 | ** our free block will leave an alignment gap which is smaller, we can
|
---|
1119 | ** trim a leading free block and release it back to the pool. We must
|
---|
1120 | ** do this because the previous physical block is in use, therefore
|
---|
1121 | ** the prev_phys_block field is not valid, and we can't simply adjust
|
---|
1122 | ** the size of that block.
|
---|
1123 | */
|
---|
1124 | const size_t gap_minimum = sizeof(block_header_t);
|
---|
1125 | const size_t size_with_gap = adjust_request_size(adjust + align + gap_minimum, align);
|
---|
1126 |
|
---|
1127 | /*
|
---|
1128 | ** If alignment is less than or equals base alignment, we're done.
|
---|
1129 | ** If we requested 0 bytes, return null, as tlsf_malloc(0) does.
|
---|
1130 | */
|
---|
1131 | const size_t aligned_size = (adjust && align > ALIGN_SIZE) ? size_with_gap : adjust;
|
---|
1132 |
|
---|
1133 | block_header_t* block = block_locate_free(control, aligned_size);
|
---|
1134 |
|
---|
1135 | /* This can't be a static assert. */
|
---|
1136 | tlsf_assert(sizeof(block_header_t) == block_size_min + block_header_overhead);
|
---|
1137 |
|
---|
1138 | if (block)
|
---|
1139 | {
|
---|
1140 | void* ptr = block_to_ptr(block);
|
---|
1141 | void* aligned = align_ptr(ptr, align);
|
---|
1142 | size_t gap = tlsf_cast(size_t,
|
---|
1143 | tlsf_cast(tlsfptr_t, aligned) - tlsf_cast(tlsfptr_t, ptr));
|
---|
1144 |
|
---|
1145 | /* If gap size is too small, offset to next aligned boundary. */
|
---|
1146 | if (gap && gap < gap_minimum)
|
---|
1147 | {
|
---|
1148 | const size_t gap_remain = gap_minimum - gap;
|
---|
1149 | const size_t offset = tlsf_max(gap_remain, align);
|
---|
1150 | const void* next_aligned = tlsf_cast(void*,
|
---|
1151 | tlsf_cast(tlsfptr_t, aligned) + offset);
|
---|
1152 |
|
---|
1153 | aligned = align_ptr(next_aligned, align);
|
---|
1154 | gap = tlsf_cast(size_t,
|
---|
1155 | tlsf_cast(tlsfptr_t, aligned) - tlsf_cast(tlsfptr_t, ptr));
|
---|
1156 | }
|
---|
1157 |
|
---|
1158 | if (gap)
|
---|
1159 | {
|
---|
1160 | tlsf_assert(gap >= gap_minimum && "gap size too small");
|
---|
1161 | block = block_trim_free_leading(control, block, gap);
|
---|
1162 | }
|
---|
1163 | }
|
---|
1164 |
|
---|
1165 | return block_prepare_used(control, block, adjust);
|
---|
1166 | }
|
---|
1167 |
|
---|
1168 | void tlsf_free(tlsf_t tlsf, void* ptr)
|
---|
1169 | {
|
---|
1170 | /* Don't attempt to free a NULL pointer. */
|
---|
1171 | if (ptr)
|
---|
1172 | {
|
---|
1173 | control_t* control = tlsf_cast(control_t*, tlsf);
|
---|
1174 | block_header_t* block = block_from_ptr(ptr);
|
---|
1175 | tlsf_assert(!block_is_free(block) && "block already marked as free");
|
---|
1176 | block_mark_as_free(block);
|
---|
1177 | block = block_merge_prev(control, block);
|
---|
1178 | block = block_merge_next(control, block);
|
---|
1179 | block_insert(control, block);
|
---|
1180 | }
|
---|
1181 | }
|
---|
1182 |
|
---|
1183 | /*
|
---|
1184 | ** The TLSF block information provides us with enough information to
|
---|
1185 | ** provide a reasonably intelligent implementation of realloc, growing or
|
---|
1186 | ** shrinking the currently allocated block as required.
|
---|
1187 | **
|
---|
1188 | ** This routine handles the somewhat esoteric edge cases of realloc:
|
---|
1189 | ** - a non-zero size with a null pointer will behave like malloc
|
---|
1190 | ** - a zero size with a non-null pointer will behave like free
|
---|
1191 | ** - a request that cannot be satisfied will leave the original buffer
|
---|
1192 | ** untouched
|
---|
1193 | ** - an extended buffer size will leave the newly-allocated area with
|
---|
1194 | ** contents undefined
|
---|
1195 | */
|
---|
1196 | void* tlsf_realloc(tlsf_t tlsf, void* ptr, size_t size)
|
---|
1197 | {
|
---|
1198 | control_t* control = tlsf_cast(control_t*, tlsf);
|
---|
1199 | void* p = 0;
|
---|
1200 |
|
---|
1201 | /* Zero-size requests are treated as free. */
|
---|
1202 | if (ptr && size == 0)
|
---|
1203 | {
|
---|
1204 | tlsf_free(tlsf, ptr);
|
---|
1205 | }
|
---|
1206 | /* Requests with NULL pointers are treated as malloc. */
|
---|
1207 | else if (!ptr)
|
---|
1208 | {
|
---|
1209 | p = tlsf_malloc(tlsf, size);
|
---|
1210 | }
|
---|
1211 | else
|
---|
1212 | {
|
---|
1213 | block_header_t* block = block_from_ptr(ptr);
|
---|
1214 | block_header_t* next = block_next(block);
|
---|
1215 |
|
---|
1216 | const size_t cursize = block_size(block);
|
---|
1217 | const size_t combined = cursize + block_size(next) + block_header_overhead;
|
---|
1218 | const size_t adjust = adjust_request_size(size, ALIGN_SIZE);
|
---|
1219 |
|
---|
1220 | tlsf_assert(!block_is_free(block) && "block already marked as free");
|
---|
1221 |
|
---|
1222 | /*
|
---|
1223 | ** If the next block is used, or when combined with the current
|
---|
1224 | ** block, does not offer enough space, we must reallocate and copy.
|
---|
1225 | */
|
---|
1226 | if (adjust > cursize && (!block_is_free(next) || adjust > combined))
|
---|
1227 | {
|
---|
1228 | p = tlsf_malloc(tlsf, size);
|
---|
1229 | if (p)
|
---|
1230 | {
|
---|
1231 | const size_t minsize = tlsf_min(cursize, size);
|
---|
1232 | memcpy(p, ptr, minsize);
|
---|
1233 | tlsf_free(tlsf, ptr);
|
---|
1234 | }
|
---|
1235 | }
|
---|
1236 | else
|
---|
1237 | {
|
---|
1238 | /* Do we need to expand to the next block? */
|
---|
1239 | if (adjust > cursize)
|
---|
1240 | {
|
---|
1241 | block_merge_next(control, block);
|
---|
1242 | block_mark_as_used(block);
|
---|
1243 | }
|
---|
1244 |
|
---|
1245 | /* Trim the resulting block and return the original pointer. */
|
---|
1246 | block_trim_used(control, block, adjust);
|
---|
1247 | p = ptr;
|
---|
1248 | }
|
---|
1249 | }
|
---|
1250 |
|
---|
1251 | return p;
|
---|
1252 | }
|
---|