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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 #define NGX_SLAB_PAGE_MASK 3
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11 #define NGX_SLAB_PAGE 0
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12 #define NGX_SLAB_BIG 1
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13 #define NGX_SLAB_EXACT 2
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14 #define NGX_SLAB_SMALL 3
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15
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16 #if (NGX_PTR_SIZE == 4)
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17
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18 #define NGX_SLAB_PAGE_FREE 0
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19 #define NGX_SLAB_PAGE_BUSY 0xffffffff
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20 #define NGX_SLAB_PAGE_START 0x80000000
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21
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22 #define NGX_SLAB_SHIFT_MASK 0x0000000f
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23 #define NGX_SLAB_MAP_MASK 0xffff0000
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24 #define NGX_SLAB_MAP_SHIFT 16
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25
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26 #define NGX_SLAB_BUSY 0xffffffff
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27
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28 #else /* (NGX_PTR_SIZE == 8) */
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29
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30 #define NGX_SLAB_PAGE_FREE 0
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31 #define NGX_SLAB_PAGE_BUSY 0xffffffffffffffff
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32 #define NGX_SLAB_PAGE_START 0x8000000000000000
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33
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34 #define NGX_SLAB_SHIFT_MASK 0x000000000000000f
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35 #define NGX_SLAB_MAP_MASK 0xffffffff00000000
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36 #define NGX_SLAB_MAP_SHIFT 32
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37
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38 #define NGX_SLAB_BUSY 0xffffffffffffffff
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39
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40 #endif
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41
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42
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43 #if (NGX_DEBUG_MALLOC)
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358
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44
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646
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45 #define ngx_slab_junk(p, size) ngx_memset(p, 0xA5, size)
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358
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46
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258
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47 #else
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358
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48
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646
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49 #if (NGX_HAVE_DEBUG_MALLOC)
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358
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50
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51 #define ngx_slab_junk(p, size) \
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646
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52 if (ngx_debug_malloc) ngx_memset(p, 0xA5, size)
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358
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53
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54 #else
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55
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258
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56 #define ngx_slab_junk(p, size)
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358
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57
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58 #endif
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59
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258
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60 #endif
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61
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62 static ngx_slab_page_t *ngx_slab_alloc_pages(ngx_slab_pool_t *pool,
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63 ngx_uint_t pages);
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64 static void ngx_slab_free_pages(ngx_slab_pool_t *pool, ngx_slab_page_t *page,
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65 ngx_uint_t pages);
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468
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66 static void ngx_slab_error(ngx_slab_pool_t *pool, ngx_uint_t level,
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67 char *text);
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258
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68
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69
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70 static ngx_uint_t ngx_slab_max_size;
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71 static ngx_uint_t ngx_slab_exact_size;
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72 static ngx_uint_t ngx_slab_exact_shift;
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73
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74
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75 void
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76 ngx_slab_init(ngx_slab_pool_t *pool)
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77 {
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78 u_char *p;
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79 size_t size;
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80 ngx_int_t m;
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81 ngx_uint_t i, n, pages;
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82 ngx_slab_page_t *slots;
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83
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84 /* STUB */
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85 if (ngx_slab_max_size == 0) {
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86 ngx_slab_max_size = ngx_pagesize / 2;
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87 ngx_slab_exact_size = ngx_pagesize / (8 * sizeof(uintptr_t));
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88 for (n = ngx_slab_exact_size; n >>= 1; ngx_slab_exact_shift++) {
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89 /* void */
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90 }
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91 }
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92 /**/
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93
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94 pool->min_size = 1 << pool->min_shift;
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95
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96 p = (u_char *) pool + sizeof(ngx_slab_pool_t);
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97 size = pool->end - p;
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98
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99 ngx_slab_junk(p, size);
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100
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101 slots = (ngx_slab_page_t *) p;
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102 n = ngx_pagesize_shift - pool->min_shift;
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103
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104 for (i = 0; i < n; i++) {
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105 slots[i].slab = 0;
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106 slots[i].next = &slots[i];
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107 slots[i].prev = 0;
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108 }
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109
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110 p += n * sizeof(ngx_slab_page_t);
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111
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348
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112 pages = (ngx_uint_t) (size / (ngx_pagesize + sizeof(ngx_slab_page_t)));
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258
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113
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114 ngx_memzero(p, pages * sizeof(ngx_slab_page_t));
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115
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116 pool->pages = (ngx_slab_page_t *) p;
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117
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118 pool->free.prev = 0;
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119 pool->free.next = (ngx_slab_page_t *) p;
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120
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121 pool->pages->slab = pages;
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122 pool->pages->next = &pool->free;
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123 pool->pages->prev = (uintptr_t) &pool->free;
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124
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125 pool->start = (u_char *)
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274
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126 ngx_align_ptr((uintptr_t) p + pages * sizeof(ngx_slab_page_t),
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258
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127 ngx_pagesize);
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128
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129 m = pages - (pool->end - pool->start) / ngx_pagesize;
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130 if (m > 0) {
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131 pages -= m;
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132 pool->pages->slab = pages;
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133 }
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134
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468
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135 pool->log_ctx = &pool->zero;
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136 pool->zero = '\0';
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258
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137 }
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138
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139
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140 void *
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141 ngx_slab_alloc(ngx_slab_pool_t *pool, size_t size)
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142 {
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272
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143 void *p;
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144
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145 ngx_shmtx_lock(&pool->mutex);
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146
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147 p = ngx_slab_alloc_locked(pool, size);
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148
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149 ngx_shmtx_unlock(&pool->mutex);
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150
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151 return p;
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152 }
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153
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154
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155 void *
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156 ngx_slab_alloc_locked(ngx_slab_pool_t *pool, size_t size)
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157 {
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258
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158 size_t s;
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260
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159 uintptr_t p, n, m, mask, *bitmap;
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160 ngx_uint_t i, slot, shift, map;
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258
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161 ngx_slab_page_t *page, *prev, *slots;
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162
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272
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163 if (size >= ngx_slab_max_size) {
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258
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164
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272
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165 ngx_log_debug1(NGX_LOG_DEBUG_ALLOC, ngx_cycle->log, 0,
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166 "slab alloc: %uz", size);
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167
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258
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168 page = ngx_slab_alloc_pages(pool, (size + ngx_pagesize - 1)
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169 >> ngx_pagesize_shift);
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170 if (page) {
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171 p = (page - pool->pages) << ngx_pagesize_shift;
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172 p += (uintptr_t) pool->start;
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173
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174 } else {
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175 p = 0;
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176 }
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177
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178 goto done;
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179 }
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180
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181 if (size > pool->min_size) {
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182 shift = 1;
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183 for (s = size - 1; s >>= 1; shift++) { /* void */ }
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184 slot = shift - pool->min_shift;
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185
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186 } else {
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187 size = pool->min_size;
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188 shift = pool->min_shift;
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189 slot = 0;
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190 }
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191
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192 ngx_log_debug2(NGX_LOG_DEBUG_ALLOC, ngx_cycle->log, 0,
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193 "slab alloc: %uz slot: %ui", size, slot);
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194
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195 slots = (ngx_slab_page_t *) ((u_char *) pool + sizeof(ngx_slab_pool_t));
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196 page = slots[slot].next;
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197
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198 if (page->next != page) {
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199
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272
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200 if (shift < ngx_slab_exact_shift) {
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258
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201
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202 do {
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203 p = (page - pool->pages) << ngx_pagesize_shift;
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204 bitmap = (uintptr_t *) (pool->start + p);
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205
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206 map = (1 << (ngx_pagesize_shift - shift))
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207 / (sizeof(uintptr_t) * 8);
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208
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209 for (n = 0; n < map; n++) {
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210
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211 if (bitmap[n] != NGX_SLAB_BUSY) {
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212
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213 for (m = 1, i = 0; m; m <<= 1, i++) {
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214 if ((bitmap[n] & m)) {
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215 continue;
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216 }
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217
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218 bitmap[n] |= m;
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272
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219
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220 i = ((n * sizeof(uintptr_t) * 8) << shift)
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221 + (i << shift);
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258
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222
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223 if (bitmap[n] == NGX_SLAB_BUSY) {
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224 for (n = n + 1; n < map; n++) {
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225 if (bitmap[n] != NGX_SLAB_BUSY) {
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226 p = (uintptr_t) bitmap + i;
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227
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228 goto done;
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229 }
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230 }
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231
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232 prev = (ngx_slab_page_t *)
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233 (page->prev & ~NGX_SLAB_PAGE_MASK);
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234 prev->next = page->next;
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235 page->next->prev = page->prev;
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236
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237 page->next = NULL;
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238 page->prev = NGX_SLAB_SMALL;
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239 }
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240
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241 p = (uintptr_t) bitmap + i;
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242
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243 goto done;
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244 }
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245 }
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246 }
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247
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248 page = page->next;
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249
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250 } while (page);
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251
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272
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252 } else if (shift == ngx_slab_exact_shift) {
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258
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253
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254 do {
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255 if (page->slab != NGX_SLAB_BUSY) {
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256
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257 for (m = 1, i = 0; m; m <<= 1, i++) {
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258 if ((page->slab & m)) {
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259 continue;
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260 }
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261
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262 page->slab |= m;
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263
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264 if (page->slab == NGX_SLAB_BUSY) {
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265 prev = (ngx_slab_page_t *)
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266 (page->prev & ~NGX_SLAB_PAGE_MASK);
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267 prev->next = page->next;
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268 page->next->prev = page->prev;
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269
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270 page->next = NULL;
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271 page->prev = NGX_SLAB_EXACT;
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272 }
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273
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274 p = (page - pool->pages) << ngx_pagesize_shift;
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275 p += i << shift;
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276 p += (uintptr_t) pool->start;
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277
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278 goto done;
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279 }
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280 }
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281
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282 page = page->next;
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283
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284 } while (page);
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285
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272
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286 } else { /* shift > ngx_slab_exact_shift */
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258
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287
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288 n = ngx_pagesize_shift - (page->slab & NGX_SLAB_SHIFT_MASK);
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289 n = 1 << n;
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274
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290 n = ((uintptr_t) 1 << n) - 1;
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258
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291 mask = n << NGX_SLAB_MAP_SHIFT;
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292
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293 do {
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294 if ((page->slab & NGX_SLAB_MAP_MASK) != mask) {
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295
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260
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296 for (m = (uintptr_t) 1 << NGX_SLAB_MAP_SHIFT, i = 0;
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258
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297 m & mask;
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298 m <<= 1, i++)
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299 {
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300 if ((page->slab & m)) {
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301 continue;
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302 }
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303
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304 page->slab |= m;
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305
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306 if ((page->slab & NGX_SLAB_MAP_MASK) == mask) {
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307 prev = (ngx_slab_page_t *)
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308 (page->prev & ~NGX_SLAB_PAGE_MASK);
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309 prev->next = page->next;
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310 page->next->prev = page->prev;
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311
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312 page->next = NULL;
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313 page->prev = NGX_SLAB_BIG;
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314 }
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315
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316 p = (page - pool->pages) << ngx_pagesize_shift;
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317 p += i << shift;
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318 p += (uintptr_t) pool->start;
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319
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320 goto done;
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321 }
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322 }
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323
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324 page = page->next;
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325
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326 } while (page);
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327 }
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328 }
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329
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330 page = ngx_slab_alloc_pages(pool, 1);
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331
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332 if (page) {
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272
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333 if (shift < ngx_slab_exact_shift) {
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258
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334 p = (page - pool->pages) << ngx_pagesize_shift;
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335 bitmap = (uintptr_t *) (pool->start + p);
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336
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337 s = 1 << shift;
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338 n = (1 << (ngx_pagesize_shift - shift)) / 8 / s;
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339
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340 if (n == 0) {
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341 n = 1;
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342 }
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343
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344 bitmap[0] = (2 << n) - 1;
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345
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346 map = (1 << (ngx_pagesize_shift - shift)) / (sizeof(uintptr_t) * 8);
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347
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348 for (i = 1; i < map; i++) {
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349 bitmap[i] = 0;
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350 }
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351
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352 page->slab = shift;
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353 page->next = &slots[slot];
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354 page->prev = (uintptr_t) &slots[slot] | NGX_SLAB_SMALL;
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355
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356 slots[slot].next = page;
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357
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358 p = ((page - pool->pages) << ngx_pagesize_shift) + s * n;
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359 p += (uintptr_t) pool->start;
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360
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361 goto done;
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362
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272
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363 } else if (shift == ngx_slab_exact_shift) {
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258
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364
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365 page->slab = 1;
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366 page->next = &slots[slot];
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367 page->prev = (uintptr_t) &slots[slot] | NGX_SLAB_EXACT;
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368
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369 slots[slot].next = page;
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370
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371 p = (page - pool->pages) << ngx_pagesize_shift;
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372 p += (uintptr_t) pool->start;
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373
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374 goto done;
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375
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272
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376 } else { /* shift > ngx_slab_exact_shift */
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258
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377
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260
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378 page->slab = ((uintptr_t) 1 << NGX_SLAB_MAP_SHIFT) | shift;
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258
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379 page->next = &slots[slot];
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380 page->prev = (uintptr_t) &slots[slot] | NGX_SLAB_BIG;
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381
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382 slots[slot].next = page;
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383
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384 p = (page - pool->pages) << ngx_pagesize_shift;
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385 p += (uintptr_t) pool->start;
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386
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387 goto done;
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388 }
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389 }
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390
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391 p = 0;
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392
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393 done:
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394
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395 ngx_log_debug1(NGX_LOG_DEBUG_ALLOC, ngx_cycle->log, 0, "slab alloc: %p", p);
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396
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397 return (void *) p;
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398 }
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399
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400
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401 void
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402 ngx_slab_free(ngx_slab_pool_t *pool, void *p)
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403 {
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272
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404 ngx_shmtx_lock(&pool->mutex);
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405
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406 ngx_slab_free_locked(pool, p);
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407
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408 ngx_shmtx_unlock(&pool->mutex);
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409 }
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410
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411
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412 void
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413 ngx_slab_free_locked(ngx_slab_pool_t *pool, void *p)
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414 {
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|
258
|
415 size_t size;
|
|
274
|
416 uintptr_t slab, m, *bitmap;
|
|
|
417 ngx_uint_t n, type, slot, shift, map;
|
|
258
|
418 ngx_slab_page_t *slots, *page;
|
|
|
419
|
|
|
420 ngx_log_debug1(NGX_LOG_DEBUG_ALLOC, ngx_cycle->log, 0, "slab free: %p", p);
|
|
|
421
|
|
|
422 if ((u_char *) p < pool->start || (u_char *) p > pool->end) {
|
|
468
|
423 ngx_slab_error(pool, NGX_LOG_ALERT, "ngx_slab_free(): outside of pool");
|
|
258
|
424 goto fail;
|
|
|
425 }
|
|
|
426
|
|
|
427 n = ((u_char *) p - pool->start) >> ngx_pagesize_shift;
|
|
|
428 page = &pool->pages[n];
|
|
|
429 slab = page->slab;
|
|
|
430 type = page->prev & NGX_SLAB_PAGE_MASK;
|
|
|
431
|
|
|
432 switch (type) {
|
|
|
433
|
|
|
434 case NGX_SLAB_SMALL:
|
|
|
435
|
|
|
436 shift = slab & NGX_SLAB_SHIFT_MASK;
|
|
|
437 size = 1 << shift;
|
|
|
438
|
|
|
439 if ((uintptr_t) p & (size - 1)) {
|
|
|
440 goto wrong_chunk;
|
|
|
441 }
|
|
|
442
|
|
|
443 n = ((uintptr_t) p & (ngx_pagesize - 1)) >> shift;
|
|
274
|
444 m = (uintptr_t) 1 << (n & (sizeof(uintptr_t) * 8 - 1));
|
|
258
|
445 n /= (sizeof(uintptr_t) * 8);
|
|
|
446 bitmap = (uintptr_t *) ((uintptr_t) p & ~(ngx_pagesize - 1));
|
|
|
447
|
|
|
448 if (bitmap[n] & m) {
|
|
|
449
|
|
|
450 if (page->next == NULL) {
|
|
|
451 slots = (ngx_slab_page_t *)
|
|
|
452 ((u_char *) pool + sizeof(ngx_slab_pool_t));
|
|
|
453 slot = shift - pool->min_shift;
|
|
|
454
|
|
|
455 page->next = slots[slot].next;
|
|
|
456 slots[slot].next = page;
|
|
|
457
|
|
|
458 page->prev = (uintptr_t) &slots[slot] | NGX_SLAB_SMALL;
|
|
|
459 page->next->prev = (uintptr_t) page | NGX_SLAB_SMALL;
|
|
|
460 }
|
|
|
461
|
|
|
462 bitmap[n] &= ~m;
|
|
|
463
|
|
|
464 n = (1 << (ngx_pagesize_shift - shift)) / 8 / (1 << shift);
|
|
|
465
|
|
|
466 if (n == 0) {
|
|
|
467 n = 1;
|
|
|
468 }
|
|
|
469
|
|
274
|
470 if (bitmap[0] & ~(((uintptr_t) 1 << n) - 1)) {
|
|
258
|
471 goto done;
|
|
|
472 }
|
|
|
473
|
|
|
474 map = (1 << (ngx_pagesize_shift - shift)) / (sizeof(uintptr_t) * 8);
|
|
|
475
|
|
|
476 for (n = 1; n < map; n++) {
|
|
|
477 if (bitmap[n]) {
|
|
|
478 goto done;
|
|
|
479 }
|
|
|
480 }
|
|
|
481
|
|
|
482 ngx_slab_free_pages(pool, page, 1);
|
|
|
483
|
|
|
484 goto done;
|
|
|
485 }
|
|
|
486
|
|
|
487 goto chunk_already_free;
|
|
|
488
|
|
|
489 case NGX_SLAB_EXACT:
|
|
|
490
|
|
274
|
491 m = (uintptr_t) 1 <<
|
|
|
492 (((uintptr_t) p & (ngx_pagesize - 1)) >> ngx_slab_exact_shift);
|
|
258
|
493 size = ngx_slab_exact_size;
|
|
|
494
|
|
|
495 if ((uintptr_t) p & (size - 1)) {
|
|
|
496 goto wrong_chunk;
|
|
|
497 }
|
|
|
498
|
|
|
499 if (slab & m) {
|
|
|
500 if (slab == NGX_SLAB_BUSY) {
|
|
|
501 slots = (ngx_slab_page_t *)
|
|
|
502 ((u_char *) pool + sizeof(ngx_slab_pool_t));
|
|
|
503 slot = ngx_slab_exact_shift - pool->min_shift;
|
|
|
504
|
|
|
505 page->next = slots[slot].next;
|
|
|
506 slots[slot].next = page;
|
|
|
507
|
|
|
508 page->prev = (uintptr_t) &slots[slot] | NGX_SLAB_EXACT;
|
|
|
509 page->next->prev = (uintptr_t) page | NGX_SLAB_EXACT;
|
|
|
510 }
|
|
|
511
|
|
|
512 page->slab &= ~m;
|
|
|
513
|
|
|
514 if (page->slab) {
|
|
|
515 goto done;
|
|
|
516 }
|
|
|
517
|
|
|
518 ngx_slab_free_pages(pool, page, 1);
|
|
|
519
|
|
|
520 goto done;
|
|
|
521 }
|
|
|
522
|
|
|
523 goto chunk_already_free;
|
|
|
524
|
|
|
525 case NGX_SLAB_BIG:
|
|
|
526
|
|
|
527 shift = slab & NGX_SLAB_SHIFT_MASK;
|
|
|
528 size = 1 << shift;
|
|
|
529
|
|
|
530 if ((uintptr_t) p & (size - 1)) {
|
|
|
531 goto wrong_chunk;
|
|
|
532 }
|
|
|
533
|
|
274
|
534 m = (uintptr_t) 1 << ((((uintptr_t) p & (ngx_pagesize - 1)) >> shift)
|
|
|
535 + NGX_SLAB_MAP_SHIFT);
|
|
258
|
536
|
|
|
537 if (slab & m) {
|
|
|
538
|
|
|
539 if (page->next == NULL) {
|
|
|
540 slots = (ngx_slab_page_t *)
|
|
|
541 ((u_char *) pool + sizeof(ngx_slab_pool_t));
|
|
|
542 slot = shift - pool->min_shift;
|
|
|
543
|
|
|
544 page->next = slots[slot].next;
|
|
|
545 slots[slot].next = page;
|
|
|
546
|
|
|
547 page->prev = (uintptr_t) &slots[slot] | NGX_SLAB_BIG;
|
|
|
548 page->next->prev = (uintptr_t) page | NGX_SLAB_BIG;
|
|
|
549 }
|
|
|
550
|
|
|
551 page->slab &= ~m;
|
|
|
552
|
|
|
553 if (page->slab & NGX_SLAB_MAP_MASK) {
|
|
|
554 goto done;
|
|
|
555 }
|
|
|
556
|
|
|
557 ngx_slab_free_pages(pool, page, 1);
|
|
|
558
|
|
|
559 goto done;
|
|
|
560 }
|
|
|
561
|
|
|
562 goto chunk_already_free;
|
|
|
563
|
|
|
564 case NGX_SLAB_PAGE:
|
|
|
565
|
|
|
566 if ((uintptr_t) p & (ngx_pagesize - 1)) {
|
|
|
567 goto wrong_chunk;
|
|
|
568 }
|
|
|
569
|
|
|
570 if (slab == NGX_SLAB_PAGE_FREE) {
|
|
468
|
571 ngx_slab_error(pool, NGX_LOG_ALERT,
|
|
|
572 "ngx_slab_free(): page is already free");
|
|
258
|
573 goto fail;
|
|
|
574 }
|
|
|
575
|
|
|
576 if (slab == NGX_SLAB_PAGE_BUSY) {
|
|
468
|
577 ngx_slab_error(pool, NGX_LOG_ALERT,
|
|
|
578 "ngx_slab_free(): pointer to wrong page");
|
|
258
|
579 goto fail;
|
|
|
580 }
|
|
|
581
|
|
|
582 n = ((u_char *) p - pool->start) >> ngx_pagesize_shift;
|
|
|
583 size = slab & ~NGX_SLAB_PAGE_START;
|
|
|
584
|
|
|
585 ngx_slab_free_pages(pool, &pool->pages[n], size);
|
|
|
586
|
|
480
|
587 ngx_slab_junk(p, size << ngx_pagesize_shift);
|
|
258
|
588
|
|
480
|
589 return;
|
|
258
|
590 }
|
|
|
591
|
|
|
592 /* not reached */
|
|
|
593
|
|
|
594 return;
|
|
|
595
|
|
|
596 done:
|
|
|
597
|
|
|
598 ngx_slab_junk(p, size);
|
|
|
599
|
|
|
600 return;
|
|
|
601
|
|
|
602 wrong_chunk:
|
|
|
603
|
|
468
|
604 ngx_slab_error(pool, NGX_LOG_ALERT,
|
|
|
605 "ngx_slab_free(): pointer to wrong chunk");
|
|
258
|
606
|
|
|
607 goto fail;
|
|
|
608
|
|
|
609 chunk_already_free:
|
|
|
610
|
|
468
|
611 ngx_slab_error(pool, NGX_LOG_ALERT,
|
|
|
612 "ngx_slab_free(): chunk is already free");
|
|
258
|
613
|
|
|
614 fail:
|
|
|
615
|
|
|
616 return;
|
|
|
617 }
|
|
|
618
|
|
|
619
|
|
|
620 static ngx_slab_page_t *
|
|
|
621 ngx_slab_alloc_pages(ngx_slab_pool_t *pool, ngx_uint_t pages)
|
|
|
622 {
|
|
|
623 ngx_slab_page_t *page, *p;
|
|
|
624
|
|
|
625 for (page = pool->free.next; page != &pool->free; page = page->next) {
|
|
|
626
|
|
|
627 if (page->slab >= pages) {
|
|
|
628
|
|
|
629 if (page->slab > pages) {
|
|
|
630 page[pages].slab = page->slab - pages;
|
|
|
631 page[pages].next = page->next;
|
|
|
632 page[pages].prev = page->prev;
|
|
|
633
|
|
|
634 p = (ngx_slab_page_t *) page->prev;
|
|
|
635 p->next = &page[pages];
|
|
|
636 page->next->prev = (uintptr_t) &page[pages];
|
|
|
637
|
|
|
638 } else {
|
|
|
639 p = (ngx_slab_page_t *) page->prev;
|
|
|
640 p->next = page->next;
|
|
|
641 page->next->prev = page->prev;
|
|
|
642 }
|
|
|
643
|
|
|
644 page->slab = pages | NGX_SLAB_PAGE_START;
|
|
|
645 page->next = NULL;
|
|
|
646 page->prev = NGX_SLAB_PAGE;
|
|
|
647
|
|
|
648 if (--pages == 0) {
|
|
|
649 return page;
|
|
|
650 }
|
|
|
651
|
|
|
652 for (p = page + 1; pages; pages--) {
|
|
|
653 p->slab = NGX_SLAB_PAGE_BUSY;
|
|
|
654 p->next = NULL;
|
|
|
655 p->prev = NGX_SLAB_PAGE;
|
|
|
656 p++;
|
|
|
657 }
|
|
|
658
|
|
|
659 return page;
|
|
|
660 }
|
|
|
661 }
|
|
|
662
|
|
468
|
663 ngx_slab_error(pool, NGX_LOG_CRIT, "ngx_slab_alloc() failed: no memory");
|
|
272
|
664
|
|
258
|
665 return NULL;
|
|
|
666 }
|
|
|
667
|
|
|
668
|
|
|
669 static void
|
|
|
670 ngx_slab_free_pages(ngx_slab_pool_t *pool, ngx_slab_page_t *page,
|
|
|
671 ngx_uint_t pages)
|
|
|
672 {
|
|
|
673 ngx_slab_page_t *prev;
|
|
|
674
|
|
|
675 page->slab = pages--;
|
|
|
676
|
|
|
677 if (pages) {
|
|
|
678 ngx_memzero(&page[1], pages * sizeof(ngx_slab_page_t));
|
|
|
679 }
|
|
|
680
|
|
272
|
681 if (page->next) {
|
|
|
682 prev = (ngx_slab_page_t *) (page->prev & ~NGX_SLAB_PAGE_MASK);
|
|
|
683 prev->next = page->next;
|
|
|
684 page->next->prev = page->prev;
|
|
|
685 }
|
|
258
|
686
|
|
272
|
687 page->prev = (uintptr_t) &pool->free;
|
|
258
|
688 page->next = pool->free.next;
|
|
272
|
689
|
|
|
690 page->next->prev = (uintptr_t) page;
|
|
|
691
|
|
258
|
692 pool->free.next = page;
|
|
|
693 }
|
|
468
|
694
|
|
|
695
|
|
|
696 static void
|
|
|
697 ngx_slab_error(ngx_slab_pool_t *pool, ngx_uint_t level, char *text)
|
|
|
698 {
|
|
|
699 ngx_log_error(level, ngx_cycle->log, 0, "%s%s", text, pool->log_ctx);
|
|
|
700 }
|
