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258
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1
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2 /*
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3 * Copyright (C) Igor Sysoev
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4 */
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5
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6 #include <ngx_config.h>
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7 #include <ngx_core.h>
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8
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9 /*
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10
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11 12
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12 2048 2 11
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13 1024 4 10
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14 512 8 9
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15 256 16 8
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16
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17 128 32 4 32 7
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18
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19 64 64 8 63 6 1
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20 32 128 16 127 5 1
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21 16 256 32 254 4 2
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22 8 512 64 504 3 8
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23
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24 */
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25
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26
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27 #define NGX_SLAB_PAGE_MASK 3
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28 #define NGX_SLAB_PAGE 0
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29 #define NGX_SLAB_BIG 1
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30 #define NGX_SLAB_EXACT 2
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31 #define NGX_SLAB_SMALL 3
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32
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33 #if (NGX_PTR_SIZE == 4)
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34
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35 #define NGX_SLAB_PAGE_FREE 0
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36 #define NGX_SLAB_PAGE_BUSY 0xffffffff
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37 #define NGX_SLAB_PAGE_START 0x80000000
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38
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39 #define NGX_SLAB_SHIFT_MASK 0x0000000f
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40 #define NGX_SLAB_MAP_MASK 0xffff0000
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41 #define NGX_SLAB_MAP_SHIFT 16
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42
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43 #define NGX_SLAB_BUSY 0xffffffff
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44
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45 #else /* (NGX_PTR_SIZE == 8) */
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46
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47 #define NGX_SLAB_PAGE_FREE 0
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48 #define NGX_SLAB_PAGE_BUSY 0xffffffffffffffff
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49 #define NGX_SLAB_PAGE_START 0x8000000000000000
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50
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51 #define NGX_SLAB_SHIFT_MASK 0x000000000000000f
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52 #define NGX_SLAB_MAP_MASK 0xffffffff00000000
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53 #define NGX_SLAB_MAP_SHIFT 32
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54
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55 #define NGX_SLAB_BUSY 0xffffffffffffffff
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56
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57 #endif
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58
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59
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60 #if (NGX_DEBUG_MALLOC)
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61 #define ngx_slab_junk(p, size) ngx_memset(p, 0xD0, size)
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62 #else
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63 #define ngx_slab_junk(p, size)
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64 #endif
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65
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66 static ngx_slab_page_t *ngx_slab_alloc_pages(ngx_slab_pool_t *pool,
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67 ngx_uint_t pages);
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68 static void ngx_slab_free_pages(ngx_slab_pool_t *pool, ngx_slab_page_t *page,
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69 ngx_uint_t pages);
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70
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71
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72 static ngx_uint_t ngx_slab_max_size;
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73 static ngx_uint_t ngx_slab_exact_size;
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74 static ngx_uint_t ngx_slab_exact_shift;
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75
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76
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77 void
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78 ngx_slab_init(ngx_slab_pool_t *pool)
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79 {
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80 u_char *p;
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81 size_t size;
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82 ngx_int_t m;
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83 ngx_uint_t i, n, pages;
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84 ngx_slab_page_t *slots;
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85
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86 /* STUB */
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87 if (ngx_slab_max_size == 0) {
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88 ngx_slab_max_size = ngx_pagesize / 2;
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89 ngx_slab_exact_size = ngx_pagesize / (8 * sizeof(uintptr_t));
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90 for (n = ngx_slab_exact_size; n >>= 1; ngx_slab_exact_shift++) {
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91 /* void */
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92 }
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93 }
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94 /**/
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95
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96 pool->min_size = 1 << pool->min_shift;
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97
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98 p = (u_char *) pool + sizeof(ngx_slab_pool_t);
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99 size = pool->end - p;
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100
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101 ngx_slab_junk(p, size);
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102
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103 slots = (ngx_slab_page_t *) p;
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104 n = ngx_pagesize_shift - pool->min_shift;
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105
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106 for (i = 0; i < n; i++) {
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107 slots[i].slab = 0;
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108 slots[i].next = &slots[i];
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109 slots[i].prev = 0;
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110 }
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111
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112 p += n * sizeof(ngx_slab_page_t);
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113
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114 /* STUB: possible overflow on 64-bit platform */
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115 pages = (ngx_uint_t) ((uint64_t) size * ngx_pagesize
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116 / (ngx_pagesize + sizeof(ngx_slab_page_t))
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117 / ngx_pagesize);
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118
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119 ngx_memzero(p, pages * sizeof(ngx_slab_page_t));
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120
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121 pool->pages = (ngx_slab_page_t *) p;
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122
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123 pool->free.prev = 0;
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124 pool->free.next = (ngx_slab_page_t *) p;
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125
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126 pool->pages->slab = pages;
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127 pool->pages->next = &pool->free;
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128 pool->pages->prev = (uintptr_t) &pool->free;
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129
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130 pool->start = (u_char *)
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131 ngx_align((uintptr_t) p + pages * sizeof(ngx_slab_page_t),
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132 ngx_pagesize);
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133
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134 m = pages - (pool->end - pool->start) / ngx_pagesize;
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135 if (m > 0) {
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136 pages -= m;
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137 pool->pages->slab = pages;
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138 }
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139
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140 #if 0
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141 ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, 0, "slab: %p, %p, %ui, %d",
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142 pool, pool->start, pages,
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143 (pool->end - pool->start) / ngx_pagesize - pages);
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144 #endif
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145 }
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146
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147
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148 void *
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149 ngx_slab_alloc(ngx_slab_pool_t *pool, size_t size)
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150 {
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151 size_t s;
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152 uintptr_t p, mask, *bitmap;
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153 ngx_uint_t i, n, m, slot, shift, map;
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154 ngx_slab_page_t *page, *prev, *slots;
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155
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156 ngx_shmtx_lock(&pool->mutex);
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157
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158 if (size >= ngx_slab_max_size) {
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159 page = ngx_slab_alloc_pages(pool, (size + ngx_pagesize - 1)
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160 >> ngx_pagesize_shift);
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161 if (page) {
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162 p = (page - pool->pages) << ngx_pagesize_shift;
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163 p += (uintptr_t) pool->start;
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164
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165 } else {
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166 p = 0;
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167 }
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168
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169 goto done;
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170 }
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171
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172 if (size > pool->min_size) {
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173 shift = 1;
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174 for (s = size - 1; s >>= 1; shift++) { /* void */ }
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175 slot = shift - pool->min_shift;
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176
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177 } else {
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178 size = pool->min_size;
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179 shift = pool->min_shift;
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180 slot = 0;
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181 }
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182
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183 ngx_log_debug2(NGX_LOG_DEBUG_ALLOC, ngx_cycle->log, 0,
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184 "slab alloc: %uz slot: %ui", size, slot);
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185
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186 slots = (ngx_slab_page_t *) ((u_char *) pool + sizeof(ngx_slab_pool_t));
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187 page = slots[slot].next;
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188
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189 #if 0
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190 ngx_log_debug2(NGX_LOG_DEBUG_ALLOC, ngx_cycle->log, 0,
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191 "slab alloc: page %p next: %p", page, page->next);
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192 #endif
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193
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194 if (page->next != page) {
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195
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196 if (size < ngx_slab_exact_size) {
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197
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198 do {
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199 p = (page - pool->pages) << ngx_pagesize_shift;
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200 bitmap = (uintptr_t *) (pool->start + p);
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201
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202 map = (1 << (ngx_pagesize_shift - shift))
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203 / (sizeof(uintptr_t) * 8);
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204
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205 for (n = 0; n < map; n++) {
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206
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207 if (bitmap[n] != NGX_SLAB_BUSY) {
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208
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209 for (m = 1, i = 0; m; m <<= 1, i++) {
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210 if ((bitmap[n] & m)) {
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211 continue;
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212 }
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213
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214 bitmap[n] |= m;
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215 i <<= shift;
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216
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217 if (bitmap[n] == NGX_SLAB_BUSY) {
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218 for (n = n + 1; n < map; n++) {
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219 if (bitmap[n] != NGX_SLAB_BUSY) {
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220 p = (uintptr_t) bitmap + i;
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221
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222 goto done;
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223 }
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224 }
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225
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226 prev = (ngx_slab_page_t *)
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227 (page->prev & ~NGX_SLAB_PAGE_MASK);
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228 prev->next = page->next;
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229 page->next->prev = page->prev;
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230
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231 page->next = NULL;
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232 page->prev = NGX_SLAB_SMALL;
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233 }
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234
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235 p = (uintptr_t) bitmap + i;
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236
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237 goto done;
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238 }
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239 }
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240 }
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241
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242 page = page->next;
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243
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244 } while (page);
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245
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246 } else if (size == ngx_slab_exact_size) {
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247
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248 do {
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249 if (page->slab != NGX_SLAB_BUSY) {
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250
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251 for (m = 1, i = 0; m; m <<= 1, i++) {
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252 if ((page->slab & m)) {
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253 continue;
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254 }
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255
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256 page->slab |= m;
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257
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258 if (page->slab == NGX_SLAB_BUSY) {
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259 prev = (ngx_slab_page_t *)
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260 (page->prev & ~NGX_SLAB_PAGE_MASK);
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261 prev->next = page->next;
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262 page->next->prev = page->prev;
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263
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264 page->next = NULL;
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265 page->prev = NGX_SLAB_EXACT;
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266 }
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267
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268 p = (page - pool->pages) << ngx_pagesize_shift;
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269 p += i << shift;
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270 p += (uintptr_t) pool->start;
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271
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272 goto done;
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273 }
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274 }
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275
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276 page = page->next;
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277
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278 } while (page);
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279
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280 } else { /* size < ngx_pagesize */
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281
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282 n = ngx_pagesize_shift - (page->slab & NGX_SLAB_SHIFT_MASK);
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283 n = 1 << n;
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284 n = (1 << n) - 1;
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285 mask = n << NGX_SLAB_MAP_SHIFT;
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286
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287 do {
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288 if ((page->slab & NGX_SLAB_MAP_MASK) != mask) {
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289
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290 for (m = 1 << NGX_SLAB_MAP_SHIFT, i = 0;
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291 m & mask;
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292 m <<= 1, i++)
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293 {
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294 if ((page->slab & m)) {
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295 continue;
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296 }
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297
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298 page->slab |= m;
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299
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300 if ((page->slab & NGX_SLAB_MAP_MASK) == mask) {
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301 prev = (ngx_slab_page_t *)
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302 (page->prev & ~NGX_SLAB_PAGE_MASK);
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303 prev->next = page->next;
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304 page->next->prev = page->prev;
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305
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306 page->next = NULL;
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307 page->prev = NGX_SLAB_BIG;
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308 }
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309
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310 p = (page - pool->pages) << ngx_pagesize_shift;
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311 p += i << shift;
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312 p += (uintptr_t) pool->start;
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313
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314 goto done;
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315 }
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316 }
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317
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318 page = page->next;
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319
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320 } while (page);
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321 }
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322 }
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323
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324 page = ngx_slab_alloc_pages(pool, 1);
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325
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326 if (page) {
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327 if (size < ngx_slab_exact_size) {
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328 p = (page - pool->pages) << ngx_pagesize_shift;
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329 bitmap = (uintptr_t *) (pool->start + p);
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330
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331 s = 1 << shift;
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332 n = (1 << (ngx_pagesize_shift - shift)) / 8 / s;
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333
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334 if (n == 0) {
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335 n = 1;
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336 }
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337
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338 bitmap[0] = (2 << n) - 1;
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339
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340 map = (1 << (ngx_pagesize_shift - shift)) / (sizeof(uintptr_t) * 8);
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341
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342 for (i = 1; i < map; i++) {
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343 bitmap[i] = 0;
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344 }
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345
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346 page->slab = shift;
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347 page->next = &slots[slot];
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348 page->prev = (uintptr_t) &slots[slot] | NGX_SLAB_SMALL;
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349
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350 slots[slot].next = page;
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351
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352 p = ((page - pool->pages) << ngx_pagesize_shift) + s * n;
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353 p += (uintptr_t) pool->start;
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354
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355 goto done;
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356
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357 } else if (size == ngx_slab_exact_size) {
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358
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359 page->slab = 1;
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360 page->next = &slots[slot];
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361 page->prev = (uintptr_t) &slots[slot] | NGX_SLAB_EXACT;
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362
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363 slots[slot].next = page;
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364
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365 p = (page - pool->pages) << ngx_pagesize_shift;
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366 p += (uintptr_t) pool->start;
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367
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368 goto done;
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369
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370 } else { /* size < ngx_pagesize */
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371
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372 page->slab = (1 << NGX_SLAB_MAP_SHIFT) | shift;
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373 page->next = &slots[slot];
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374 page->prev = (uintptr_t) &slots[slot] | NGX_SLAB_BIG;
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375
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376 slots[slot].next = page;
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377
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378 p = (page - pool->pages) << ngx_pagesize_shift;
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379 p += (uintptr_t) pool->start;
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380
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381 goto done;
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382 }
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383 }
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384
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385 p = 0;
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386
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387 done:
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388
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389 ngx_shmtx_unlock(&pool->mutex);
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390
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391 ngx_log_debug1(NGX_LOG_DEBUG_ALLOC, ngx_cycle->log, 0, "slab alloc: %p", p);
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392
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393 return (void *) p;
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394 }
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395
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396
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397 void
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398 ngx_slab_free(ngx_slab_pool_t *pool, void *p)
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399 {
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400 size_t size;
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401 uintptr_t slab, *bitmap;
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402 ngx_uint_t n, m, type, slot, shift, map;
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403 ngx_slab_page_t *slots, *page;
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404
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405 ngx_log_debug1(NGX_LOG_DEBUG_ALLOC, ngx_cycle->log, 0, "slab free: %p", p);
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406
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407 ngx_shmtx_lock(&pool->mutex);
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408
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409 if ((u_char *) p < pool->start || (u_char *) p > pool->end) {
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410 ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, 0,
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411 "ngx_slab_free(): outside of pool");
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412 goto fail;
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413 }
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414
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415 n = ((u_char *) p - pool->start) >> ngx_pagesize_shift;
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416 page = &pool->pages[n];
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417 slab = page->slab;
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418 type = page->prev & NGX_SLAB_PAGE_MASK;
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|
|
419
|
|
|
420 switch (type) {
|
|
|
421
|
|
|
422 case NGX_SLAB_SMALL:
|
|
|
423
|
|
|
424 shift = slab & NGX_SLAB_SHIFT_MASK;
|
|
|
425 size = 1 << shift;
|
|
|
426
|
|
|
427 if ((uintptr_t) p & (size - 1)) {
|
|
|
428 goto wrong_chunk;
|
|
|
429 }
|
|
|
430
|
|
|
431 n = ((uintptr_t) p & (ngx_pagesize - 1)) >> shift;
|
|
|
432 m = 1 << (n & (sizeof(uintptr_t) * 8 - 1));
|
|
|
433 n /= (sizeof(uintptr_t) * 8);
|
|
|
434 bitmap = (uintptr_t *) ((uintptr_t) p & ~(ngx_pagesize - 1));
|
|
|
435
|
|
|
436 if (bitmap[n] & m) {
|
|
|
437
|
|
|
438 if (page->next == NULL) {
|
|
|
439 slots = (ngx_slab_page_t *)
|
|
|
440 ((u_char *) pool + sizeof(ngx_slab_pool_t));
|
|
|
441 slot = shift - pool->min_shift;
|
|
|
442
|
|
|
443 page->next = slots[slot].next;
|
|
|
444 slots[slot].next = page;
|
|
|
445
|
|
|
446 page->prev = (uintptr_t) &slots[slot] | NGX_SLAB_SMALL;
|
|
|
447 page->next->prev = (uintptr_t) page | NGX_SLAB_SMALL;
|
|
|
448 }
|
|
|
449
|
|
|
450 bitmap[n] &= ~m;
|
|
|
451
|
|
|
452 n = (1 << (ngx_pagesize_shift - shift)) / 8 / (1 << shift);
|
|
|
453
|
|
|
454 if (n == 0) {
|
|
|
455 n = 1;
|
|
|
456 }
|
|
|
457
|
|
|
458 if (bitmap[0] & ~((1 << n) - 1)) {
|
|
|
459 goto done;
|
|
|
460 }
|
|
|
461
|
|
|
462 map = (1 << (ngx_pagesize_shift - shift)) / (sizeof(uintptr_t) * 8);
|
|
|
463
|
|
|
464 for (n = 1; n < map; n++) {
|
|
|
465 if (bitmap[n]) {
|
|
|
466 goto done;
|
|
|
467 }
|
|
|
468 }
|
|
|
469
|
|
|
470 ngx_slab_free_pages(pool, page, 1);
|
|
|
471
|
|
|
472 goto done;
|
|
|
473 }
|
|
|
474
|
|
|
475 goto chunk_already_free;
|
|
|
476
|
|
|
477 case NGX_SLAB_EXACT:
|
|
|
478
|
|
|
479 m = 1 << (((uintptr_t) p & (ngx_pagesize - 1)) >> ngx_slab_exact_shift);
|
|
|
480 size = ngx_slab_exact_size;
|
|
|
481
|
|
|
482 if ((uintptr_t) p & (size - 1)) {
|
|
|
483 goto wrong_chunk;
|
|
|
484 }
|
|
|
485
|
|
|
486 if (slab & m) {
|
|
|
487 if (slab == NGX_SLAB_BUSY) {
|
|
|
488 slots = (ngx_slab_page_t *)
|
|
|
489 ((u_char *) pool + sizeof(ngx_slab_pool_t));
|
|
|
490 slot = ngx_slab_exact_shift - pool->min_shift;
|
|
|
491
|
|
|
492 page->next = slots[slot].next;
|
|
|
493 slots[slot].next = page;
|
|
|
494
|
|
|
495 page->prev = (uintptr_t) &slots[slot] | NGX_SLAB_EXACT;
|
|
|
496 page->next->prev = (uintptr_t) page | NGX_SLAB_EXACT;
|
|
|
497 }
|
|
|
498
|
|
|
499 page->slab &= ~m;
|
|
|
500
|
|
|
501 if (page->slab) {
|
|
|
502 goto done;
|
|
|
503 }
|
|
|
504
|
|
|
505 ngx_slab_free_pages(pool, page, 1);
|
|
|
506
|
|
|
507 goto done;
|
|
|
508 }
|
|
|
509
|
|
|
510 goto chunk_already_free;
|
|
|
511
|
|
|
512 case NGX_SLAB_BIG:
|
|
|
513
|
|
|
514 shift = slab & NGX_SLAB_SHIFT_MASK;
|
|
|
515 size = 1 << shift;
|
|
|
516
|
|
|
517 if ((uintptr_t) p & (size - 1)) {
|
|
|
518 goto wrong_chunk;
|
|
|
519 }
|
|
|
520
|
|
|
521 m = 1 << ((((uintptr_t) p & (ngx_pagesize - 1)) >> shift)
|
|
|
522 + NGX_SLAB_MAP_SHIFT);
|
|
|
523
|
|
|
524 if (slab & m) {
|
|
|
525
|
|
|
526 if (page->next == NULL) {
|
|
|
527 slots = (ngx_slab_page_t *)
|
|
|
528 ((u_char *) pool + sizeof(ngx_slab_pool_t));
|
|
|
529 slot = shift - pool->min_shift;
|
|
|
530
|
|
|
531 page->next = slots[slot].next;
|
|
|
532 slots[slot].next = page;
|
|
|
533
|
|
|
534 page->prev = (uintptr_t) &slots[slot] | NGX_SLAB_BIG;
|
|
|
535 page->next->prev = (uintptr_t) page | NGX_SLAB_BIG;
|
|
|
536 }
|
|
|
537
|
|
|
538 page->slab &= ~m;
|
|
|
539
|
|
|
540 if (page->slab & NGX_SLAB_MAP_MASK) {
|
|
|
541 goto done;
|
|
|
542 }
|
|
|
543
|
|
|
544 ngx_slab_free_pages(pool, page, 1);
|
|
|
545
|
|
|
546 goto done;
|
|
|
547 }
|
|
|
548
|
|
|
549 goto chunk_already_free;
|
|
|
550
|
|
|
551 case NGX_SLAB_PAGE:
|
|
|
552
|
|
|
553 if ((uintptr_t) p & (ngx_pagesize - 1)) {
|
|
|
554 goto wrong_chunk;
|
|
|
555 }
|
|
|
556
|
|
|
557 if (slab == NGX_SLAB_PAGE_FREE) {
|
|
|
558 ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, 0,
|
|
|
559 "ngx_slab_free(): page is already free");
|
|
|
560 goto fail;
|
|
|
561 }
|
|
|
562
|
|
|
563 if (slab == NGX_SLAB_PAGE_BUSY) {
|
|
|
564 ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, 0,
|
|
|
565 "ngx_slab_free(): pointer to wrong page");
|
|
|
566 goto fail;
|
|
|
567 }
|
|
|
568
|
|
|
569 n = ((u_char *) p - pool->start) >> ngx_pagesize_shift;
|
|
|
570 size = slab & ~NGX_SLAB_PAGE_START;
|
|
|
571
|
|
|
572 ngx_slab_free_pages(pool, &pool->pages[n], size);
|
|
|
573
|
|
|
574 size <<= ngx_pagesize_shift;
|
|
|
575
|
|
|
576 goto done;
|
|
|
577 }
|
|
|
578
|
|
|
579 /* not reached */
|
|
|
580
|
|
|
581 return;
|
|
|
582
|
|
|
583 done:
|
|
|
584
|
|
|
585 ngx_slab_junk(p, size);
|
|
|
586
|
|
|
587 ngx_shmtx_unlock(&pool->mutex);
|
|
|
588
|
|
|
589 return;
|
|
|
590
|
|
|
591 wrong_chunk:
|
|
|
592
|
|
|
593 ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, 0,
|
|
|
594 "ngx_slab_free(): pointer to wrong chunk");
|
|
|
595
|
|
|
596 goto fail;
|
|
|
597
|
|
|
598 chunk_already_free:
|
|
|
599
|
|
|
600 ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, 0,
|
|
|
601 "ngx_slab_free(): chunk is already free");
|
|
|
602
|
|
|
603 fail:
|
|
|
604
|
|
|
605 ngx_shmtx_unlock(&pool->mutex);
|
|
|
606
|
|
|
607 return;
|
|
|
608 }
|
|
|
609
|
|
|
610
|
|
|
611 static ngx_slab_page_t *
|
|
|
612 ngx_slab_alloc_pages(ngx_slab_pool_t *pool, ngx_uint_t pages)
|
|
|
613 {
|
|
|
614 ngx_slab_page_t *page, *p;
|
|
|
615
|
|
|
616 for (page = pool->free.next; page != &pool->free; page = page->next) {
|
|
|
617
|
|
|
618 if (page->slab >= pages) {
|
|
|
619
|
|
|
620 if (page->slab > pages) {
|
|
|
621 page[pages].slab = page->slab - pages;
|
|
|
622 page[pages].next = page->next;
|
|
|
623 page[pages].prev = page->prev;
|
|
|
624
|
|
|
625 p = (ngx_slab_page_t *) page->prev;
|
|
|
626 p->next = &page[pages];
|
|
|
627 page->next->prev = (uintptr_t) &page[pages];
|
|
|
628
|
|
|
629 } else {
|
|
|
630 p = (ngx_slab_page_t *) page->prev;
|
|
|
631 p->next = page->next;
|
|
|
632 page->next->prev = page->prev;
|
|
|
633 }
|
|
|
634
|
|
|
635 page->slab = pages | NGX_SLAB_PAGE_START;
|
|
|
636
|
|
|
637 #if (NGX_DEBUG)
|
|
|
638 page->next = NULL;
|
|
|
639 page->prev = NGX_SLAB_PAGE;
|
|
|
640 #endif
|
|
|
641
|
|
|
642 if (--pages == 0) {
|
|
|
643 return page;
|
|
|
644 }
|
|
|
645
|
|
|
646 for (p = page + 1; pages; pages--) {
|
|
|
647 p->slab = NGX_SLAB_PAGE_BUSY;
|
|
|
648 #if (NGX_DEBUG)
|
|
|
649 p->next = NULL;
|
|
|
650 p->prev = NGX_SLAB_PAGE;
|
|
|
651 #endif
|
|
|
652 p++;
|
|
|
653 }
|
|
|
654
|
|
|
655 return page;
|
|
|
656 }
|
|
|
657 }
|
|
|
658
|
|
|
659 ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, NGX_ENOMEM,
|
|
|
660 "ngx_slab_alloc(): failed");
|
|
|
661 return NULL;
|
|
|
662 }
|
|
|
663
|
|
|
664
|
|
|
665 static void
|
|
|
666 ngx_slab_free_pages(ngx_slab_pool_t *pool, ngx_slab_page_t *page,
|
|
|
667 ngx_uint_t pages)
|
|
|
668 {
|
|
|
669 ngx_slab_page_t *prev;
|
|
|
670
|
|
|
671 page->slab = pages--;
|
|
|
672
|
|
|
673 if (pages) {
|
|
|
674 ngx_memzero(&page[1], pages * sizeof(ngx_slab_page_t));
|
|
|
675 }
|
|
|
676
|
|
|
677 prev = (ngx_slab_page_t *) (page->prev & ~NGX_SLAB_PAGE_MASK);
|
|
|
678 prev->next = page->next;
|
|
|
679
|
|
|
680 page->next = pool->free.next;
|
|
|
681 pool->free.next = page;
|
|
|
682
|
|
|
683 page->prev = page->next->prev;
|
|
|
684 page->next->prev = (uintptr_t) page;
|
|
|
685 }
|
