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