[279] | 1 | #include <assert.h>
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| 2 | #include <limits.h>
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| 3 | #include <stddef.h>
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| 4 | #include <stdio.h>
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| 5 | #include <stdlib.h>
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| 6 | #include <string.h>
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| 7 | #include "syssvc/syslog.h"
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| 8 |
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| 9 | #include "tlsf.h"
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| 10 |
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| 11 | #undef _MSC_VER
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| 12 |
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| 13 | #if defined(__cplusplus)
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| 14 | #define tlsf_decl inline
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| 15 | #else
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| 16 | #define tlsf_decl static
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| 17 | #endif
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| 18 |
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| 19 | /*
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| 20 | ** Architecture-specific bit manipulation routines.
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| 21 | **
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| 22 | ** TLSF achieves O(1) cost for malloc and free operations by limiting
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| 23 | ** the search for a free block to a free list of guaranteed size
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| 24 | ** adequate to fulfill the request, combined with efficient free list
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| 25 | ** queries using bitmasks and architecture-specific bit-manipulation
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| 26 | ** routines.
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| 27 | **
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| 28 | ** Most modern processors provide instructions to count leading zeroes
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| 29 | ** in a word, find the lowest and highest set bit, etc. These
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| 30 | ** specific implementations will be used when available, falling back
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| 31 | ** to a reasonably efficient generic implementation.
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| 32 | **
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| 33 | ** NOTE: TLSF spec relies on ffs/fls returning value 0..31.
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| 34 | ** ffs/fls return 1-32 by default, returning 0 for error.
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| 35 | */
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| 36 |
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| 37 | /*
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| 38 | ** Detect whether or not we are building for a 32- or 64-bit (LP/LLP)
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| 39 | ** architecture. There is no reliable portable method at compile-time.
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| 40 | */
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| 41 | #if defined (__alpha__) || defined (__ia64__) || defined (__x86_64__) \
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| 42 | || defined (_WIN64) || defined (__LP64__) || defined (__LLP64__)
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| 43 | #define TLSF_64BIT
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| 44 | #endif
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| 45 |
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| 46 | /*
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| 47 | ** gcc 3.4 and above have builtin support, specialized for architecture.
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| 48 | ** Some compilers masquerade as gcc; patchlevel test filters them out.
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| 49 | */
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| 50 | #if defined (__GNUC__) && (__GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4)) \
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| 51 | && defined (__GNUC_PATCHLEVEL__)
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| 52 |
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| 53 | #if defined (__SNC__)
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| 54 | /* SNC for Playstation 3. */
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| 55 |
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| 56 | tlsf_decl int tlsf_ffs(unsigned int word)
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| 57 | {
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| 58 | const unsigned int reverse = word & (~word + 1);
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| 59 | const int bit = 32 - __builtin_clz(reverse);
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| 60 | return bit - 1;
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| 61 | }
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| 62 |
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| 63 | #else
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| 64 |
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| 65 | tlsf_decl int tlsf_ffs(unsigned int word)
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| 66 | {
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| 67 | return __builtin_ffs(word) - 1;
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| 68 | }
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| 69 |
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| 70 | #endif
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| 71 |
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| 72 | tlsf_decl int tlsf_fls(unsigned int word)
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| 73 | {
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| 74 | const int bit = word ? 32 - __builtin_clz(word) : 0;
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| 75 | return bit - 1;
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| 76 | }
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| 77 |
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| 78 | #elif defined (_MSC_VER) && (_MSC_VER >= 1400) && (defined (_M_IX86) || defined (_M_X64))
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| 79 | /* Microsoft Visual C++ support on x86/X64 architectures. */
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| 80 |
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| 81 | #include <intrin.h>
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| 82 |
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| 83 | #pragma intrinsic(_BitScanReverse)
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| 84 | #pragma intrinsic(_BitScanForward)
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| 85 |
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| 86 | tlsf_decl int tlsf_fls(unsigned int word)
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| 87 | {
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| 88 | unsigned long index;
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| 89 | return _BitScanReverse(&index, word) ? index : -1;
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| 90 | }
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| 91 |
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| 92 | tlsf_decl int tlsf_ffs(unsigned int word)
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| 93 | {
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| 94 | unsigned long index;
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| 95 | return _BitScanForward(&index, word) ? index : -1;
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| 96 | }
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| 97 |
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| 98 | #elif defined (_MSC_VER) && defined (_M_PPC)
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| 99 | /* Microsoft Visual C++ support on PowerPC architectures. */
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| 100 |
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| 101 | #include <ppcintrinsics.h>
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| 102 |
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| 103 | tlsf_decl int tlsf_fls(unsigned int word)
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| 104 | {
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| 105 | const int bit = 32 - _CountLeadingZeros(word);
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| 106 | return bit - 1;
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| 107 | }
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| 108 |
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| 109 | tlsf_decl int tlsf_ffs(unsigned int word)
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| 110 | {
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| 111 | const unsigned int reverse = word & (~word + 1);
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| 112 | const int bit = 32 - _CountLeadingZeros(reverse);
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| 113 | return bit - 1;
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| 114 | }
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| 115 |
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| 116 | #elif defined (__ARMCC_VERSION)
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| 117 | /* RealView Compilation Tools for ARM */
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| 118 |
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| 119 | tlsf_decl int tlsf_ffs(unsigned int word)
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| 120 | {
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| 121 | const unsigned int reverse = word & (~word + 1);
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| 122 | const int bit = 32 - __clz(reverse);
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| 123 | return bit - 1;
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| 124 | }
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| 125 |
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| 126 | tlsf_decl int tlsf_fls(unsigned int word)
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| 127 | {
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| 128 | const int bit = word ? 32 - __clz(word) : 0;
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| 129 | return bit - 1;
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| 130 | }
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| 131 |
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| 132 | #elif defined (__ghs__)
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| 133 | /* Green Hills support for PowerPC */
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| 134 |
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| 135 | #include <ppc_ghs.h>
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| 136 |
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| 137 | tlsf_decl int tlsf_ffs(unsigned int word)
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| 138 | {
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| 139 | const unsigned int reverse = word & (~word + 1);
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| 140 | const int bit = 32 - __CLZ32(reverse);
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| 141 | return bit - 1;
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| 142 | }
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| 143 |
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| 144 | tlsf_decl int tlsf_fls(unsigned int word)
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| 145 | {
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| 146 | const int bit = word ? 32 - __CLZ32(word) : 0;
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| 147 | return bit - 1;
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| 148 | }
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| 149 |
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| 150 | #else
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| 151 | /* Fall back to generic implementation. */
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| 152 |
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| 153 | tlsf_decl int tlsf_fls_generic(unsigned int word)
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| 154 | {
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| 155 | int bit = 32;
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| 156 |
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| 157 | if (!word) bit -= 1;
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| 158 | if (!(word & 0xffff0000)) { word <<= 16; bit -= 16; }
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| 159 | if (!(word & 0xff000000)) { word <<= 8; bit -= 8; }
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| 160 | if (!(word & 0xf0000000)) { word <<= 4; bit -= 4; }
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| 161 | if (!(word & 0xc0000000)) { word <<= 2; bit -= 2; }
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| 162 | if (!(word & 0x80000000)) { word <<= 1; bit -= 1; }
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| 163 |
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| 164 | return bit;
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| 165 | }
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| 166 |
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| 167 | /* Implement ffs in terms of fls. */
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| 168 | tlsf_decl int tlsf_ffs(unsigned int word)
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| 169 | {
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| 170 | return tlsf_fls_generic(word & (~word + 1)) - 1;
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| 171 | }
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| 172 |
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| 173 | tlsf_decl int tlsf_fls(unsigned int word)
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| 174 | {
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| 175 | return tlsf_fls_generic(word) - 1;
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| 176 | }
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| 177 |
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| 178 | #endif
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| 179 |
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| 180 | /* Possibly 64-bit version of tlsf_fls. */
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| 181 | #if defined (TLSF_64BIT)
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| 182 | tlsf_decl int tlsf_fls_sizet(size_t size)
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| 183 | {
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| 184 | int high = (int)(size >> 32);
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| 185 | int bits = 0;
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| 186 | if (high)
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| 187 | {
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| 188 | bits = 32 + tlsf_fls(high);
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| 189 | }
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| 190 | else
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| 191 | {
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| 192 | bits = tlsf_fls((int)size & 0xffffffff);
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| 193 |
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| 194 | }
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| 195 | return bits;
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| 196 | }
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| 197 | #else
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| 198 | #define tlsf_fls_sizet tlsf_fls
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| 199 | #endif
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| 200 |
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| 201 | #undef tlsf_decl
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| 202 |
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| 203 | /*
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| 204 | ** Constants.
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| 205 | */
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| 206 |
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| 207 | /* Public constants: may be modified. */
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| 208 | enum tlsf_public
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| 209 | {
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| 210 | /* log2 of number of linear subdivisions of block sizes. Larger
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| 211 | ** values require more memory in the control structure. Values of
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| 212 | ** 4 or 5 are typical.
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| 213 | */
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| 214 | SL_INDEX_COUNT_LOG2 = 5,
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| 215 | };
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| 216 |
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| 217 | /* Private constants: do not modify. */
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| 218 | enum tlsf_private
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| 219 | {
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| 220 | #if defined (TLSF_64BIT)
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| 221 | /* All allocation sizes and addresses are aligned to 8 bytes. */
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| 222 | ALIGN_SIZE_LOG2 = 3,
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| 223 | #else
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| 224 | /* All allocation sizes and addresses are aligned to 4 bytes. */
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| 225 | ALIGN_SIZE_LOG2 = 2,
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| 226 | #endif
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| 227 | ALIGN_SIZE = (1 << ALIGN_SIZE_LOG2),
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| 228 |
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| 229 | /*
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| 230 | ** We support allocations of sizes up to (1 << FL_INDEX_MAX) bits.
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| 231 | ** However, because we linearly subdivide the second-level lists, and
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| 232 | ** our minimum size granularity is 4 bytes, it doesn't make sense to
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| 233 | ** create first-level lists for sizes smaller than SL_INDEX_COUNT * 4,
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| 234 | ** or (1 << (SL_INDEX_COUNT_LOG2 + 2)) bytes, as there we will be
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| 235 | ** trying to split size ranges into more slots than we have available.
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| 236 | ** Instead, we calculate the minimum threshold size, and place all
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| 237 | ** blocks below that size into the 0th first-level list.
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| 238 | */
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| 239 |
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| 240 | #if defined (TLSF_64BIT)
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| 241 | /*
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| 242 | ** TODO: We can increase this to support larger sizes, at the expense
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| 243 | ** of more overhead in the TLSF structure.
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| 244 | */
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| 245 | FL_INDEX_MAX = 32,
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| 246 | #else
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| 247 | FL_INDEX_MAX = 30,
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| 248 | #endif
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| 249 | SL_INDEX_COUNT = (1 << SL_INDEX_COUNT_LOG2),
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| 250 | FL_INDEX_SHIFT = (SL_INDEX_COUNT_LOG2 + ALIGN_SIZE_LOG2),
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| 251 | FL_INDEX_COUNT = (FL_INDEX_MAX - FL_INDEX_SHIFT + 1),
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| 252 |
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| 253 | SMALL_BLOCK_SIZE = (1 << FL_INDEX_SHIFT),
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| 254 | };
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| 255 |
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| 256 | /*
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| 257 | ** Cast and min/max macros.
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| 258 | */
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| 259 |
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| 260 | #define tlsf_cast(t, exp) ((t) (exp))
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| 261 | #define tlsf_min(a, b) ((a) < (b) ? (a) : (b))
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| 262 | #define tlsf_max(a, b) ((a) > (b) ? (a) : (b))
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| 263 |
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| 264 | /*
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| 265 | ** Set assert macro, if it has not been provided by the user.
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| 266 | */
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| 267 | #if !defined (tlsf_assert)
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| 268 | #define tlsf_assert assert
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| 269 | #endif
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| 270 |
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| 271 | /*
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| 272 | ** Static assertion mechanism.
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| 273 | */
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| 274 |
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| 275 | #define _tlsf_glue2(x, y) x ## y
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| 276 | #define _tlsf_glue(x, y) _tlsf_glue2(x, y)
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| 277 | #define tlsf_static_assert(exp) \
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| 278 | typedef char _tlsf_glue(static_assert, __LINE__) [(exp) ? 1 : -1]
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| 279 |
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| 280 | /* This code has been tested on 32- and 64-bit (LP/LLP) architectures. */
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| 281 | tlsf_static_assert(sizeof(int) * CHAR_BIT == 32);
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| 282 | tlsf_static_assert(sizeof(size_t) * CHAR_BIT >= 32);
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| 283 | tlsf_static_assert(sizeof(size_t) * CHAR_BIT <= 64);
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| 284 |
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| 285 | /* SL_INDEX_COUNT must be <= number of bits in sl_bitmap's storage type. */
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| 286 | tlsf_static_assert(sizeof(unsigned int) * CHAR_BIT >= SL_INDEX_COUNT);
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| 287 |
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| 288 | /* Ensure we've properly tuned our sizes. */
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| 289 | tlsf_static_assert(ALIGN_SIZE == SMALL_BLOCK_SIZE / SL_INDEX_COUNT);
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| 290 |
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| 291 | /*
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| 292 | ** Data structures and associated constants.
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| 293 | */
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| 294 |
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| 295 | /*
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| 296 | ** Block header structure.
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| 297 | **
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| 298 | ** There are several implementation subtleties involved:
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| 299 | ** - The prev_phys_block field is only valid if the previous block is free.
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| 300 | ** - The prev_phys_block field is actually stored at the end of the
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| 301 | ** previous block. It appears at the beginning of this structure only to
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| 302 | ** simplify the implementation.
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| 303 | ** - The next_free / prev_free fields are only valid if the block is free.
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| 304 | */
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| 305 | typedef struct block_header_t
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| 306 | {
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| 307 | /* Points to the previous physical block. */
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| 308 | struct block_header_t* prev_phys_block;
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| 309 |
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| 310 | /* The size of this block, excluding the block header. */
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| 311 | size_t size;
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| 312 |
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| 313 | /* Next and previous free blocks. */
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| 314 | struct block_header_t* next_free;
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| 315 | struct block_header_t* prev_free;
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| 316 | } block_header_t;
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| 317 |
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| 318 | /*
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| 319 | ** Since block sizes are always at least a multiple of 4, the two least
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| 320 | ** significant bits of the size field are used to store the block status:
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| 321 | ** - bit 0: whether block is busy or free
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| 322 | ** - bit 1: whether previous block is busy or free
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| 323 | */
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| 324 | static const size_t block_header_free_bit = 1 << 0;
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| 325 | static const size_t block_header_prev_free_bit = 1 << 1;
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| 326 |
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| 327 | /*
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| 328 | ** The size of the block header exposed to used blocks is the size field.
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| 329 | ** The prev_phys_block field is stored *inside* the previous free block.
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| 330 | */
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| 331 | static const size_t block_header_overhead = sizeof(size_t);
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| 332 |
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| 333 | /* User data starts directly after the size field in a used block. */
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| 334 | static const size_t block_start_offset =
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| 335 | offsetof(block_header_t, size) + sizeof(size_t);
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| 336 |
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| 337 | /*
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| 338 | ** A free block must be large enough to store its header minus the size of
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| 339 | ** the prev_phys_block field, and no larger than the number of addressable
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| 340 | ** bits for FL_INDEX.
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| 341 | */
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| 342 | static const size_t block_size_min =
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| 343 | sizeof(block_header_t) - sizeof(block_header_t*);
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| 344 | static const size_t block_size_max = tlsf_cast(size_t, 1) << FL_INDEX_MAX;
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| 345 |
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| 346 |
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| 347 | /* The TLSF control structure. */
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| 348 | typedef struct control_t
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| 349 | {
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| 350 | /* Empty lists point at this block to indicate they are free. */
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| 351 | block_header_t block_null;
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| 352 |
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| 353 | /* Bitmaps for free lists. */
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| 354 | unsigned int fl_bitmap;
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| 355 | unsigned int sl_bitmap[FL_INDEX_COUNT];
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| 356 |
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| 357 | /* Head of free lists. */
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| 358 | block_header_t* blocks[FL_INDEX_COUNT][SL_INDEX_COUNT];
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| 359 | } control_t;
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| 360 |
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| 361 | /* A type used for casting when doing pointer arithmetic. */
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| 362 | typedef ptrdiff_t tlsfptr_t;
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| 363 |
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| 364 | /*
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| 365 | ** block_header_t member functions.
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| 366 | */
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| 367 |
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| 368 | static size_t block_size(const block_header_t* block)
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| 369 | {
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| 370 | return block->size & ~(block_header_free_bit | block_header_prev_free_bit);
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| 371 | }
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| 372 |
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| 373 | static void block_set_size(block_header_t* block, size_t size)
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| 374 | {
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| 375 | const size_t oldsize = block->size;
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| 376 | block->size = size | (oldsize & (block_header_free_bit | block_header_prev_free_bit));
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| 377 | }
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| 378 |
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| 379 | static int block_is_last(const block_header_t* block)
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| 380 | {
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| 381 | return block_size(block) == 0;
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| 382 | }
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| 383 |
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| 384 | static int block_is_free(const block_header_t* block)
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| 385 | {
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| 386 | return tlsf_cast(int, block->size & block_header_free_bit);
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| 387 | }
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| 388 |
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| 389 | static void block_set_free(block_header_t* block)
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| 390 | {
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| 391 | block->size |= block_header_free_bit;
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| 392 | }
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| 393 |
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| 394 | static void block_set_used(block_header_t* block)
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| 395 | {
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| 396 | block->size &= ~block_header_free_bit;
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| 397 | }
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| 398 |
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| 399 | static int block_is_prev_free(const block_header_t* block)
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| 400 | {
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| 401 | return tlsf_cast(int, block->size & block_header_prev_free_bit);
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| 402 | }
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| 403 |
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| 404 | static void block_set_prev_free(block_header_t* block)
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| 405 | {
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| 406 | block->size |= block_header_prev_free_bit;
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| 407 | }
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| 408 |
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| 409 | static void block_set_prev_used(block_header_t* block)
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| 410 | {
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| 411 | block->size &= ~block_header_prev_free_bit;
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| 412 | }
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| 413 |
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| 414 | static block_header_t* block_from_ptr(const void* ptr)
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| 415 | {
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| 416 | return tlsf_cast(block_header_t*,
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| 417 | tlsf_cast(unsigned char*, ptr) - block_start_offset);
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| 418 | }
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| 419 |
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| 420 | static void* block_to_ptr(const block_header_t* block)
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| 421 | {
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| 422 | return tlsf_cast(void*,
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| 423 | tlsf_cast(unsigned char*, block) + block_start_offset);
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| 424 | }
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| 425 |
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| 426 | /* Return location of next block after block of given size. */
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| 427 | static block_header_t* offset_to_block(const void* ptr, size_t size)
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| 428 | {
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| 429 | return tlsf_cast(block_header_t*, tlsf_cast(tlsfptr_t, ptr) + size);
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| 430 | }
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| 431 |
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| 432 | /* Return location of previous block. */
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| 433 | static block_header_t* block_prev(const block_header_t* block)
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| 434 | {
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| 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 | }
|
---|