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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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358
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61
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62 #define ngx_slab_junk(p, size) ngx_memset(p, 0xD0, size)
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63
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258
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64 #else
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358
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65
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66 #if (NGX_FREEBSD)
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67
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68 #define ngx_slab_junk(p, size) \
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69 if (ngx_freebsd_debug_malloc) ngx_memset(p, 0xD0, size)
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70
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71 #else
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72
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258
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73 #define ngx_slab_junk(p, size)
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358
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74
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75 #endif
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76
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258
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77 #endif
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78
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79 static ngx_slab_page_t *ngx_slab_alloc_pages(ngx_slab_pool_t *pool,
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80 ngx_uint_t pages);
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81 static void ngx_slab_free_pages(ngx_slab_pool_t *pool, ngx_slab_page_t *page,
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82 ngx_uint_t pages);
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83
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84
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85 static ngx_uint_t ngx_slab_max_size;
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86 static ngx_uint_t ngx_slab_exact_size;
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87 static ngx_uint_t ngx_slab_exact_shift;
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88
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89
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90 void
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91 ngx_slab_init(ngx_slab_pool_t *pool)
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92 {
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93 u_char *p;
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94 size_t size;
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95 ngx_int_t m;
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96 ngx_uint_t i, n, pages;
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97 ngx_slab_page_t *slots;
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98
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99 /* STUB */
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100 if (ngx_slab_max_size == 0) {
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101 ngx_slab_max_size = ngx_pagesize / 2;
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102 ngx_slab_exact_size = ngx_pagesize / (8 * sizeof(uintptr_t));
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103 for (n = ngx_slab_exact_size; n >>= 1; ngx_slab_exact_shift++) {
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104 /* void */
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105 }
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106 }
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107 /**/
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108
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109 pool->min_size = 1 << pool->min_shift;
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110
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111 p = (u_char *) pool + sizeof(ngx_slab_pool_t);
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112 size = pool->end - p;
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113
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114 ngx_slab_junk(p, size);
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115
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116 slots = (ngx_slab_page_t *) p;
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117 n = ngx_pagesize_shift - pool->min_shift;
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118
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119 for (i = 0; i < n; i++) {
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120 slots[i].slab = 0;
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121 slots[i].next = &slots[i];
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122 slots[i].prev = 0;
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123 }
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124
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125 p += n * sizeof(ngx_slab_page_t);
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126
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348
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127 pages = (ngx_uint_t) (size / (ngx_pagesize + sizeof(ngx_slab_page_t)));
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258
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128
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129 ngx_memzero(p, pages * sizeof(ngx_slab_page_t));
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130
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131 pool->pages = (ngx_slab_page_t *) p;
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132
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133 pool->free.prev = 0;
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134 pool->free.next = (ngx_slab_page_t *) p;
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135
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136 pool->pages->slab = pages;
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137 pool->pages->next = &pool->free;
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138 pool->pages->prev = (uintptr_t) &pool->free;
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139
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140 pool->start = (u_char *)
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274
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141 ngx_align_ptr((uintptr_t) p + pages * sizeof(ngx_slab_page_t),
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258
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142 ngx_pagesize);
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143
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144 m = pages - (pool->end - pool->start) / ngx_pagesize;
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145 if (m > 0) {
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146 pages -= m;
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147 pool->pages->slab = pages;
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148 }
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149
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150 #if 0
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151 ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, 0, "slab: %p, %p, %ui, %d",
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152 pool, pool->start, pages,
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153 (pool->end - pool->start) / ngx_pagesize - pages);
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154 #endif
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155 }
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156
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157
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158 void *
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159 ngx_slab_alloc(ngx_slab_pool_t *pool, size_t size)
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160 {
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272
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161 void *p;
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162
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163 ngx_shmtx_lock(&pool->mutex);
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164
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165 p = ngx_slab_alloc_locked(pool, size);
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166
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167 ngx_shmtx_unlock(&pool->mutex);
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168
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169 return p;
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170 }
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171
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172
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173 void *
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174 ngx_slab_alloc_locked(ngx_slab_pool_t *pool, size_t size)
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175 {
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258
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176 size_t s;
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260
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177 uintptr_t p, n, m, mask, *bitmap;
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178 ngx_uint_t i, slot, shift, map;
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258
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179 ngx_slab_page_t *page, *prev, *slots;
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180
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272
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181 if (size >= ngx_slab_max_size) {
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258
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182
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272
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183 ngx_log_debug1(NGX_LOG_DEBUG_ALLOC, ngx_cycle->log, 0,
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184 "slab alloc: %uz", size);
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185
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258
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186 page = ngx_slab_alloc_pages(pool, (size + ngx_pagesize - 1)
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187 >> ngx_pagesize_shift);
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188 if (page) {
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189 p = (page - pool->pages) << ngx_pagesize_shift;
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190 p += (uintptr_t) pool->start;
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191
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192 } else {
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193 p = 0;
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194 }
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195
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196 goto done;
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197 }
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198
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199 if (size > pool->min_size) {
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200 shift = 1;
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201 for (s = size - 1; s >>= 1; shift++) { /* void */ }
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202 slot = shift - pool->min_shift;
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203
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204 } else {
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205 size = pool->min_size;
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206 shift = pool->min_shift;
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207 slot = 0;
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208 }
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209
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210 ngx_log_debug2(NGX_LOG_DEBUG_ALLOC, ngx_cycle->log, 0,
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211 "slab alloc: %uz slot: %ui", size, slot);
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212
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213 slots = (ngx_slab_page_t *) ((u_char *) pool + sizeof(ngx_slab_pool_t));
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214 page = slots[slot].next;
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215
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216 if (page->next != page) {
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217
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272
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218 if (shift < ngx_slab_exact_shift) {
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258
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219
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220 do {
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221 p = (page - pool->pages) << ngx_pagesize_shift;
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222 bitmap = (uintptr_t *) (pool->start + p);
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223
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224 map = (1 << (ngx_pagesize_shift - shift))
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225 / (sizeof(uintptr_t) * 8);
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226
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227 for (n = 0; n < map; n++) {
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228
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229 if (bitmap[n] != NGX_SLAB_BUSY) {
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230
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231 for (m = 1, i = 0; m; m <<= 1, i++) {
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232 if ((bitmap[n] & m)) {
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233 continue;
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234 }
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235
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236 bitmap[n] |= m;
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272
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237
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238 i = ((n * sizeof(uintptr_t) * 8) << shift)
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239 + (i << shift);
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258
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240
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241 if (bitmap[n] == NGX_SLAB_BUSY) {
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242 for (n = n + 1; n < map; n++) {
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243 if (bitmap[n] != NGX_SLAB_BUSY) {
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244 p = (uintptr_t) bitmap + i;
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245
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246 goto done;
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247 }
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248 }
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249
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250 prev = (ngx_slab_page_t *)
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251 (page->prev & ~NGX_SLAB_PAGE_MASK);
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252 prev->next = page->next;
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253 page->next->prev = page->prev;
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254
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255 page->next = NULL;
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256 page->prev = NGX_SLAB_SMALL;
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257 }
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258
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259 p = (uintptr_t) bitmap + i;
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260
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261 goto done;
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262 }
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263 }
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264 }
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265
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266 page = page->next;
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267
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268 } while (page);
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269
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272
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270 } else if (shift == ngx_slab_exact_shift) {
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258
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271
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272 do {
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273 if (page->slab != NGX_SLAB_BUSY) {
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274
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275 for (m = 1, i = 0; m; m <<= 1, i++) {
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276 if ((page->slab & m)) {
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277 continue;
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278 }
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279
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280 page->slab |= m;
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281
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282 if (page->slab == NGX_SLAB_BUSY) {
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283 prev = (ngx_slab_page_t *)
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284 (page->prev & ~NGX_SLAB_PAGE_MASK);
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285 prev->next = page->next;
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286 page->next->prev = page->prev;
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287
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288 page->next = NULL;
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289 page->prev = NGX_SLAB_EXACT;
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290 }
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291
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292 p = (page - pool->pages) << ngx_pagesize_shift;
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293 p += i << shift;
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294 p += (uintptr_t) pool->start;
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295
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296 goto done;
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297 }
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298 }
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299
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300 page = page->next;
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301
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302 } while (page);
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303
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272
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304 } else { /* shift > ngx_slab_exact_shift */
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258
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305
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306 n = ngx_pagesize_shift - (page->slab & NGX_SLAB_SHIFT_MASK);
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307 n = 1 << n;
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274
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308 n = ((uintptr_t) 1 << n) - 1;
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258
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309 mask = n << NGX_SLAB_MAP_SHIFT;
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310
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311 do {
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312 if ((page->slab & NGX_SLAB_MAP_MASK) != mask) {
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313
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260
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314 for (m = (uintptr_t) 1 << NGX_SLAB_MAP_SHIFT, i = 0;
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258
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315 m & mask;
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316 m <<= 1, i++)
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317 {
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318 if ((page->slab & m)) {
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319 continue;
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320 }
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321
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322 page->slab |= m;
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323
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324 if ((page->slab & NGX_SLAB_MAP_MASK) == mask) {
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325 prev = (ngx_slab_page_t *)
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326 (page->prev & ~NGX_SLAB_PAGE_MASK);
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327 prev->next = page->next;
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328 page->next->prev = page->prev;
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329
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330 page->next = NULL;
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331 page->prev = NGX_SLAB_BIG;
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332 }
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333
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334 p = (page - pool->pages) << ngx_pagesize_shift;
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335 p += i << shift;
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336 p += (uintptr_t) pool->start;
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337
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338 goto done;
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339 }
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340 }
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341
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342 page = page->next;
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343
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344 } while (page);
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345 }
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346 }
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347
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348 page = ngx_slab_alloc_pages(pool, 1);
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349
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350 if (page) {
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272
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351 if (shift < ngx_slab_exact_shift) {
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258
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352 p = (page - pool->pages) << ngx_pagesize_shift;
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353 bitmap = (uintptr_t *) (pool->start + p);
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354
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355 s = 1 << shift;
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356 n = (1 << (ngx_pagesize_shift - shift)) / 8 / s;
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357
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358 if (n == 0) {
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359 n = 1;
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360 }
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361
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362 bitmap[0] = (2 << n) - 1;
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363
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364 map = (1 << (ngx_pagesize_shift - shift)) / (sizeof(uintptr_t) * 8);
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365
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366 for (i = 1; i < map; i++) {
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367 bitmap[i] = 0;
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368 }
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369
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370 page->slab = shift;
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371 page->next = &slots[slot];
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372 page->prev = (uintptr_t) &slots[slot] | NGX_SLAB_SMALL;
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373
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374 slots[slot].next = page;
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375
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376 p = ((page - pool->pages) << ngx_pagesize_shift) + s * n;
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377 p += (uintptr_t) pool->start;
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378
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379 goto done;
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380
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272
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381 } else if (shift == ngx_slab_exact_shift) {
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258
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382
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383 page->slab = 1;
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384 page->next = &slots[slot];
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385 page->prev = (uintptr_t) &slots[slot] | NGX_SLAB_EXACT;
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386
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387 slots[slot].next = page;
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388
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389 p = (page - pool->pages) << ngx_pagesize_shift;
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390 p += (uintptr_t) pool->start;
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391
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392 goto done;
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393
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272
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394 } else { /* shift > ngx_slab_exact_shift */
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258
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395
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260
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396 page->slab = ((uintptr_t) 1 << NGX_SLAB_MAP_SHIFT) | shift;
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258
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397 page->next = &slots[slot];
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398 page->prev = (uintptr_t) &slots[slot] | NGX_SLAB_BIG;
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399
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400 slots[slot].next = page;
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401
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402 p = (page - pool->pages) << ngx_pagesize_shift;
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403 p += (uintptr_t) pool->start;
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404
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405 goto done;
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406 }
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407 }
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408
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409 p = 0;
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410
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411 done:
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412
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413 ngx_log_debug1(NGX_LOG_DEBUG_ALLOC, ngx_cycle->log, 0, "slab alloc: %p", p);
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414
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415 return (void *) p;
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416 }
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417
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418
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419 void
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420 ngx_slab_free(ngx_slab_pool_t *pool, void *p)
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421 {
|
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272
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422 ngx_shmtx_lock(&pool->mutex);
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423
|
|
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424 ngx_slab_free_locked(pool, p);
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|
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425
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|
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426 ngx_shmtx_unlock(&pool->mutex);
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|
|
427 }
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|
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428
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|
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429
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|
|
430 void
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|
|
431 ngx_slab_free_locked(ngx_slab_pool_t *pool, void *p)
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|
432 {
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|
258
|
433 size_t size;
|
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274
|
434 uintptr_t slab, m, *bitmap;
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|
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435 ngx_uint_t n, type, slot, shift, map;
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258
|
436 ngx_slab_page_t *slots, *page;
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437
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438 ngx_log_debug1(NGX_LOG_DEBUG_ALLOC, ngx_cycle->log, 0, "slab free: %p", p);
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439
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440 if ((u_char *) p < pool->start || (u_char *) p > pool->end) {
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441 ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, 0,
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442 "ngx_slab_free(): outside of pool");
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443 goto fail;
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|
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444 }
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|
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445
|
|
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446 n = ((u_char *) p - pool->start) >> ngx_pagesize_shift;
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447 page = &pool->pages[n];
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|
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448 slab = page->slab;
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|
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449 type = page->prev & NGX_SLAB_PAGE_MASK;
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450
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|
|
451 switch (type) {
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452
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|
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453 case NGX_SLAB_SMALL:
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454
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|
455 shift = slab & NGX_SLAB_SHIFT_MASK;
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456 size = 1 << shift;
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457
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458 if ((uintptr_t) p & (size - 1)) {
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459 goto wrong_chunk;
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|
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460 }
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|
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461
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|
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462 n = ((uintptr_t) p & (ngx_pagesize - 1)) >> shift;
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274
|
463 m = (uintptr_t) 1 << (n & (sizeof(uintptr_t) * 8 - 1));
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258
|
464 n /= (sizeof(uintptr_t) * 8);
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465 bitmap = (uintptr_t *) ((uintptr_t) p & ~(ngx_pagesize - 1));
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466
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467 if (bitmap[n] & m) {
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468
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469 if (page->next == NULL) {
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470 slots = (ngx_slab_page_t *)
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|
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471 ((u_char *) pool + sizeof(ngx_slab_pool_t));
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472 slot = shift - pool->min_shift;
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473
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474 page->next = slots[slot].next;
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475 slots[slot].next = page;
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476
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477 page->prev = (uintptr_t) &slots[slot] | NGX_SLAB_SMALL;
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478 page->next->prev = (uintptr_t) page | NGX_SLAB_SMALL;
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|
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479 }
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480
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481 bitmap[n] &= ~m;
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482
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|
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483 n = (1 << (ngx_pagesize_shift - shift)) / 8 / (1 << shift);
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|
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484
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|
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485 if (n == 0) {
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486 n = 1;
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|
|
487 }
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|
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488
|
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274
|
489 if (bitmap[0] & ~(((uintptr_t) 1 << n) - 1)) {
|
|
258
|
490 goto done;
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491 }
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|
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492
|
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493 map = (1 << (ngx_pagesize_shift - shift)) / (sizeof(uintptr_t) * 8);
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|
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494
|
|
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495 for (n = 1; n < map; n++) {
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|
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496 if (bitmap[n]) {
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497 goto done;
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498 }
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|
|
499 }
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500
|
|
|
501 ngx_slab_free_pages(pool, page, 1);
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|
|
502
|
|
|
503 goto done;
|
|
|
504 }
|
|
|
505
|
|
|
506 goto chunk_already_free;
|
|
|
507
|
|
|
508 case NGX_SLAB_EXACT:
|
|
|
509
|
|
274
|
510 m = (uintptr_t) 1 <<
|
|
|
511 (((uintptr_t) p & (ngx_pagesize - 1)) >> ngx_slab_exact_shift);
|
|
258
|
512 size = ngx_slab_exact_size;
|
|
|
513
|
|
|
514 if ((uintptr_t) p & (size - 1)) {
|
|
|
515 goto wrong_chunk;
|
|
|
516 }
|
|
|
517
|
|
|
518 if (slab & m) {
|
|
|
519 if (slab == NGX_SLAB_BUSY) {
|
|
|
520 slots = (ngx_slab_page_t *)
|
|
|
521 ((u_char *) pool + sizeof(ngx_slab_pool_t));
|
|
|
522 slot = ngx_slab_exact_shift - pool->min_shift;
|
|
|
523
|
|
|
524 page->next = slots[slot].next;
|
|
|
525 slots[slot].next = page;
|
|
|
526
|
|
|
527 page->prev = (uintptr_t) &slots[slot] | NGX_SLAB_EXACT;
|
|
|
528 page->next->prev = (uintptr_t) page | NGX_SLAB_EXACT;
|
|
|
529 }
|
|
|
530
|
|
|
531 page->slab &= ~m;
|
|
|
532
|
|
|
533 if (page->slab) {
|
|
|
534 goto done;
|
|
|
535 }
|
|
|
536
|
|
|
537 ngx_slab_free_pages(pool, page, 1);
|
|
|
538
|
|
|
539 goto done;
|
|
|
540 }
|
|
|
541
|
|
|
542 goto chunk_already_free;
|
|
|
543
|
|
|
544 case NGX_SLAB_BIG:
|
|
|
545
|
|
|
546 shift = slab & NGX_SLAB_SHIFT_MASK;
|
|
|
547 size = 1 << shift;
|
|
|
548
|
|
|
549 if ((uintptr_t) p & (size - 1)) {
|
|
|
550 goto wrong_chunk;
|
|
|
551 }
|
|
|
552
|
|
274
|
553 m = (uintptr_t) 1 << ((((uintptr_t) p & (ngx_pagesize - 1)) >> shift)
|
|
|
554 + NGX_SLAB_MAP_SHIFT);
|
|
258
|
555
|
|
|
556 if (slab & m) {
|
|
|
557
|
|
|
558 if (page->next == NULL) {
|
|
|
559 slots = (ngx_slab_page_t *)
|
|
|
560 ((u_char *) pool + sizeof(ngx_slab_pool_t));
|
|
|
561 slot = shift - pool->min_shift;
|
|
|
562
|
|
|
563 page->next = slots[slot].next;
|
|
|
564 slots[slot].next = page;
|
|
|
565
|
|
|
566 page->prev = (uintptr_t) &slots[slot] | NGX_SLAB_BIG;
|
|
|
567 page->next->prev = (uintptr_t) page | NGX_SLAB_BIG;
|
|
|
568 }
|
|
|
569
|
|
|
570 page->slab &= ~m;
|
|
|
571
|
|
|
572 if (page->slab & NGX_SLAB_MAP_MASK) {
|
|
|
573 goto done;
|
|
|
574 }
|
|
|
575
|
|
|
576 ngx_slab_free_pages(pool, page, 1);
|
|
|
577
|
|
|
578 goto done;
|
|
|
579 }
|
|
|
580
|
|
|
581 goto chunk_already_free;
|
|
|
582
|
|
|
583 case NGX_SLAB_PAGE:
|
|
|
584
|
|
|
585 if ((uintptr_t) p & (ngx_pagesize - 1)) {
|
|
|
586 goto wrong_chunk;
|
|
|
587 }
|
|
|
588
|
|
|
589 if (slab == NGX_SLAB_PAGE_FREE) {
|
|
|
590 ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, 0,
|
|
|
591 "ngx_slab_free(): page is already free");
|
|
|
592 goto fail;
|
|
|
593 }
|
|
|
594
|
|
|
595 if (slab == NGX_SLAB_PAGE_BUSY) {
|
|
|
596 ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, 0,
|
|
|
597 "ngx_slab_free(): pointer to wrong page");
|
|
|
598 goto fail;
|
|
|
599 }
|
|
|
600
|
|
|
601 n = ((u_char *) p - pool->start) >> ngx_pagesize_shift;
|
|
|
602 size = slab & ~NGX_SLAB_PAGE_START;
|
|
|
603
|
|
|
604 ngx_slab_free_pages(pool, &pool->pages[n], size);
|
|
|
605
|
|
|
606 size <<= ngx_pagesize_shift;
|
|
|
607
|
|
|
608 goto done;
|
|
|
609 }
|
|
|
610
|
|
|
611 /* not reached */
|
|
|
612
|
|
|
613 return;
|
|
|
614
|
|
|
615 done:
|
|
|
616
|
|
|
617 ngx_slab_junk(p, size);
|
|
|
618
|
|
|
619 return;
|
|
|
620
|
|
|
621 wrong_chunk:
|
|
|
622
|
|
|
623 ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, 0,
|
|
|
624 "ngx_slab_free(): pointer to wrong chunk");
|
|
|
625
|
|
|
626 goto fail;
|
|
|
627
|
|
|
628 chunk_already_free:
|
|
|
629
|
|
|
630 ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, 0,
|
|
|
631 "ngx_slab_free(): chunk is already free");
|
|
|
632
|
|
|
633 fail:
|
|
|
634
|
|
|
635 return;
|
|
|
636 }
|
|
|
637
|
|
|
638
|
|
|
639 static ngx_slab_page_t *
|
|
|
640 ngx_slab_alloc_pages(ngx_slab_pool_t *pool, ngx_uint_t pages)
|
|
|
641 {
|
|
|
642 ngx_slab_page_t *page, *p;
|
|
|
643
|
|
|
644 for (page = pool->free.next; page != &pool->free; page = page->next) {
|
|
|
645
|
|
|
646 if (page->slab >= pages) {
|
|
|
647
|
|
|
648 if (page->slab > pages) {
|
|
|
649 page[pages].slab = page->slab - pages;
|
|
|
650 page[pages].next = page->next;
|
|
|
651 page[pages].prev = page->prev;
|
|
|
652
|
|
|
653 p = (ngx_slab_page_t *) page->prev;
|
|
|
654 p->next = &page[pages];
|
|
|
655 page->next->prev = (uintptr_t) &page[pages];
|
|
|
656
|
|
|
657 } else {
|
|
|
658 p = (ngx_slab_page_t *) page->prev;
|
|
|
659 p->next = page->next;
|
|
|
660 page->next->prev = page->prev;
|
|
|
661 }
|
|
|
662
|
|
|
663 page->slab = pages | NGX_SLAB_PAGE_START;
|
|
|
664
|
|
|
665 #if (NGX_DEBUG)
|
|
|
666 page->next = NULL;
|
|
|
667 page->prev = NGX_SLAB_PAGE;
|
|
|
668 #endif
|
|
|
669
|
|
|
670 if (--pages == 0) {
|
|
|
671 return page;
|
|
|
672 }
|
|
|
673
|
|
|
674 for (p = page + 1; pages; pages--) {
|
|
|
675 p->slab = NGX_SLAB_PAGE_BUSY;
|
|
|
676 #if (NGX_DEBUG)
|
|
|
677 p->next = NULL;
|
|
|
678 p->prev = NGX_SLAB_PAGE;
|
|
|
679 #endif
|
|
|
680 p++;
|
|
|
681 }
|
|
|
682
|
|
|
683 return page;
|
|
|
684 }
|
|
|
685 }
|
|
|
686
|
|
|
687 ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, NGX_ENOMEM,
|
|
|
688 "ngx_slab_alloc(): failed");
|
|
272
|
689
|
|
258
|
690 return NULL;
|
|
|
691 }
|
|
|
692
|
|
|
693
|
|
|
694 static void
|
|
|
695 ngx_slab_free_pages(ngx_slab_pool_t *pool, ngx_slab_page_t *page,
|
|
|
696 ngx_uint_t pages)
|
|
|
697 {
|
|
|
698 ngx_slab_page_t *prev;
|
|
|
699
|
|
|
700 page->slab = pages--;
|
|
|
701
|
|
|
702 if (pages) {
|
|
|
703 ngx_memzero(&page[1], pages * sizeof(ngx_slab_page_t));
|
|
|
704 }
|
|
|
705
|
|
272
|
706 if (page->next) {
|
|
|
707 prev = (ngx_slab_page_t *) (page->prev & ~NGX_SLAB_PAGE_MASK);
|
|
|
708 prev->next = page->next;
|
|
|
709 page->next->prev = page->prev;
|
|
|
710 }
|
|
258
|
711
|
|
272
|
712 page->prev = (uintptr_t) &pool->free;
|
|
258
|
713 page->next = pool->free.next;
|
|
272
|
714
|
|
|
715 page->next->prev = (uintptr_t) page;
|
|
|
716
|
|
258
|
717 pool->free.next = page;
|
|
|
718 }
|
