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0
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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
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7 #include <ngx_config.h>
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8 #include <ngx_core.h>
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9
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10 /*
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11 * The threads implementation uses the rfork(RFPROC|RFTHREAD|RFMEM) syscall
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12 * to create threads. All threads use the stacks of the same size mmap()ed
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13 * below the main stack. Thus the current thread id is determinated via
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14 * the stack pointer value.
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15 *
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16 * The mutex implementation uses the ngx_atomic_cmp_set() operation
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17 * to acquire a mutex and the SysV semaphore to wait on a mutex and to wake up
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18 * the waiting threads. The light mutex does not use semaphore, so after
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19 * spinning in the lock the thread calls sched_yield(). However the light
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20 * mutecies are intended to be used with the "trylock" operation only.
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21 * The SysV semop() is a cheap syscall, particularly if it has little sembuf's
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22 * and does not use SEM_UNDO.
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23 *
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10
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24 * The condition variable implementation uses the signal #64.
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25 * The signal handler is SIG_IGN so the kill() is a cheap syscall.
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26 * The thread waits a signal in kevent(). The use of the EVFILT_SIGNAL
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27 * is safe since FreeBSD 4.10-STABLE.
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0
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28 *
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29 * This threads implementation currently works on i386 (486+) and amd64
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30 * platforms only.
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31 */
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32
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33
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34 char *ngx_freebsd_kern_usrstack;
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35 size_t ngx_thread_stack_size;
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36
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37
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38 static size_t rz_size;
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39 static size_t usable_stack_size;
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40 static char *last_stack;
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41
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42 static ngx_uint_t nthreads;
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43 static ngx_uint_t max_threads;
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44
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45 static ngx_uint_t nkeys;
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46 static ngx_tid_t *tids; /* the threads tids array */
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47 void **ngx_tls; /* the threads tls's array */
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48
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49 /* the thread-safe libc errno */
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50
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51 static int errno0; /* the main thread's errno */
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52 static int *errnos; /* the threads errno's array */
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53
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112
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54 int *
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55 __error()
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0
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56 {
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57 int tid;
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58
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59 tid = ngx_gettid();
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60
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61 return tid ? &errnos[tid - 1] : &errno0;
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62 }
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63
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64
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65 /*
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66 * __isthreaded enables the spinlocks in some libc functions, i.e. in malloc()
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67 * and some other places. Nevertheless we protect our malloc()/free() calls
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68 * by own mutex that is more efficient than the spinlock.
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69 *
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70 * _spinlock() is a weak referenced stub in src/lib/libc/gen/_spinlock_stub.c
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71 * that does nothing.
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72 */
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73
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74 extern int __isthreaded;
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75
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112
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76 void
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77 _spinlock(ngx_atomic_t *lock)
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0
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78 {
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79 ngx_int_t tries;
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80
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81 tries = 0;
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82
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83 for ( ;; ) {
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84
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85 if (*lock) {
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86 if (ngx_ncpu > 1 && tries++ < 1000) {
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87 continue;
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88 }
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89
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90 sched_yield();
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91 tries = 0;
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92
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93 } else {
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94 if (ngx_atomic_cmp_set(lock, 0, 1)) {
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95 return;
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96 }
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97 }
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98 }
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99 }
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100
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101
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102 /*
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103 * Before FreeBSD 5.1 _spinunlock() is a simple #define in
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104 * src/lib/libc/include/spinlock.h that zeroes lock.
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105 *
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106 * Since FreeBSD 5.1 _spinunlock() is a weak referenced stub in
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107 * src/lib/libc/gen/_spinlock_stub.c that does nothing.
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108 */
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109
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110 #ifndef _spinunlock
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111
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112
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112 void
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113 _spinunlock(ngx_atomic_t *lock)
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0
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114 {
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115 *lock = 0;
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116 }
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117
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118 #endif
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119
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120
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112
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121 ngx_err_t
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122 ngx_create_thread(ngx_tid_t *tid, ngx_thread_value_t (*func)(void *arg),
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123 void *arg, ngx_log_t *log)
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0
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124 {
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10
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125 ngx_pid_t id;
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126 ngx_err_t err;
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127 char *stack, *stack_top;
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0
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128
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129 if (nthreads >= max_threads) {
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130 ngx_log_error(NGX_LOG_CRIT, log, 0,
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10
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131 "no more than %ui threads can be created", max_threads);
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0
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132 return NGX_ERROR;
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133 }
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134
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135 last_stack -= ngx_thread_stack_size;
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136
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137 stack = mmap(last_stack, usable_stack_size, PROT_READ|PROT_WRITE,
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138 MAP_STACK, -1, 0);
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139
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140 if (stack == MAP_FAILED) {
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141 ngx_log_error(NGX_LOG_ALERT, log, ngx_errno,
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10
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142 "mmap(%p:%uz, MAP_STACK) thread stack failed",
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0
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143 last_stack, usable_stack_size);
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144 return NGX_ERROR;
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145 }
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146
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147 if (stack != last_stack) {
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10
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148 ngx_log_error(NGX_LOG_ALERT, log, 0,
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149 "stack %p address was changed to %p", last_stack, stack);
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150 return NGX_ERROR;
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0
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151 }
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152
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153 stack_top = stack + usable_stack_size;
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154
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155 ngx_log_debug2(NGX_LOG_DEBUG_CORE, log, 0,
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10
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156 "thread stack: %p-%p", stack, stack_top);
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0
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157
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158 ngx_set_errno(0);
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159
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160 id = rfork_thread(RFPROC|RFTHREAD|RFMEM, stack_top,
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161 (ngx_rfork_thread_func_pt) func, arg);
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162
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163 err = ngx_errno;
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164
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165 if (id == -1) {
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166 ngx_log_error(NGX_LOG_ALERT, log, err, "rfork() failed");
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167
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168 } else {
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169 *tid = id;
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170 nthreads = (ngx_freebsd_kern_usrstack - stack_top)
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171 / ngx_thread_stack_size;
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172 tids[nthreads] = id;
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173
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10
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174 ngx_log_debug1(NGX_LOG_DEBUG_CORE, log, 0, "rfork()ed thread: %P", id);
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0
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175 }
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176
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177 return err;
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178 }
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179
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180
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112
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181 ngx_int_t
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182 ngx_init_threads(int n, size_t size, ngx_cycle_t *cycle)
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0
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183 {
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184 char *red_zone, *zone;
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185 size_t len;
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186 ngx_int_t i;
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187 struct sigaction sa;
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188
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189 max_threads = n + 1;
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190
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191 for (i = 0; i < n; i++) {
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192 ngx_memzero(&sa, sizeof(struct sigaction));
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193 sa.sa_handler = SIG_IGN;
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194 sigemptyset(&sa.sa_mask);
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195 if (sigaction(NGX_CV_SIGNAL, &sa, NULL) == -1) {
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196 ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
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197 "sigaction(%d, SIG_IGN) failed", NGX_CV_SIGNAL);
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198 return NGX_ERROR;
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199 }
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200 }
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201
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202 len = sizeof(ngx_freebsd_kern_usrstack);
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203 if (sysctlbyname("kern.usrstack", &ngx_freebsd_kern_usrstack, &len,
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204 NULL, 0) == -1)
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205 {
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206 ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
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207 "sysctlbyname(kern.usrstack) failed");
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208 return NGX_ERROR;
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209 }
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210
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211 /* the main thread stack red zone */
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212 rz_size = ngx_pagesize;
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213 red_zone = ngx_freebsd_kern_usrstack - (size + rz_size);
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214
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215 ngx_log_debug2(NGX_LOG_DEBUG_CORE, cycle->log, 0,
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10
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216 "usrstack: %p red zone: %p",
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0
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217 ngx_freebsd_kern_usrstack, red_zone);
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218
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219 zone = mmap(red_zone, rz_size, PROT_NONE, MAP_ANON, -1, 0);
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220 if (zone == MAP_FAILED) {
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221 ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
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10
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222 "mmap(%p:%uz, PROT_NONE, MAP_ANON) red zone failed",
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0
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223 red_zone, rz_size);
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224 return NGX_ERROR;
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225 }
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226
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227 if (zone != red_zone) {
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228 ngx_log_error(NGX_LOG_ALERT, cycle->log, 0,
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10
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229 "red zone %p address was changed to %p", red_zone, zone);
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230 return NGX_ERROR;
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0
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231 }
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232
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10
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233 /* create the thread errno' array */
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0
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234
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50
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235 errnos = ngx_calloc(n * sizeof(int), cycle->log);
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236 if (errnos == NULL) {
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0
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237 return NGX_ERROR;
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238 }
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239
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10
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240 /* create the thread tids array */
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0
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241
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50
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242 tids = ngx_calloc((n + 1) * sizeof(ngx_tid_t), cycle->log);
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243 if (tids == NULL) {
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0
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244 return NGX_ERROR;
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245 }
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246
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247 tids[0] = ngx_pid;
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248
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10
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249 /* create the thread tls' array */
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0
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250
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251 ngx_tls = ngx_calloc(NGX_THREAD_KEYS_MAX * (n + 1) * sizeof(void *),
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252 cycle->log);
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253 if (ngx_tls == NULL) {
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254 return NGX_ERROR;
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255 }
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256
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257 nthreads = 1;
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258
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259 last_stack = zone + rz_size;
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260 usable_stack_size = size;
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261 ngx_thread_stack_size = size + rz_size;
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262
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263 /* allow the spinlock in libc malloc() */
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264 __isthreaded = 1;
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265
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266 ngx_threaded = 1;
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267
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268 return NGX_OK;
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269 }
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270
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271
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112
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272 ngx_tid_t
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273 ngx_thread_self()
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0
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274 {
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50
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275 ngx_int_t tid;
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0
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276
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277 tid = ngx_gettid();
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278
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279 if (tids == NULL) {
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280 return ngx_pid;
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281 }
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282
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283 return tids[tid];
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284 }
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285
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286
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112
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287 ngx_err_t
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288 ngx_thread_key_create(ngx_tls_key_t *key)
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0
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289 {
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290 if (nkeys >= NGX_THREAD_KEYS_MAX) {
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291 return NGX_ENOMEM;
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292 }
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293
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294 *key = nkeys++;
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295
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296 return 0;
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297 }
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298
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299
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112
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300 ngx_err_t
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301 ngx_thread_set_tls(ngx_tls_key_t key, void *value)
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0
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302 {
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303 if (key >= NGX_THREAD_KEYS_MAX) {
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304 return NGX_EINVAL;
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305 }
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306
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307 ngx_tls[key * NGX_THREAD_KEYS_MAX + ngx_gettid()] = value;
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308 return 0;
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309 }
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310
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311
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112
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312 ngx_mutex_t *
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313 ngx_mutex_init(ngx_log_t *log, ngx_uint_t flags)
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0
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314 {
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315 ngx_mutex_t *m;
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316 union semun op;
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317
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50
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318 m = ngx_alloc(sizeof(ngx_mutex_t), log);
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319 if (m == NULL) {
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0
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320 return NULL;
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321 }
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322
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323 m->lock = 0;
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324 m->log = log;
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325
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326 if (flags & NGX_MUTEX_LIGHT) {
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327 m->semid = -1;
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328 return m;
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329 }
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330
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331 m->semid = semget(IPC_PRIVATE, 1, SEM_R|SEM_A);
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332 if (m->semid == -1) {
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333 ngx_log_error(NGX_LOG_ALERT, log, ngx_errno, "semget() failed");
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334 return NULL;
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335 }
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336
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337 op.val = 0;
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338
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339 if (semctl(m->semid, 0, SETVAL, op) == -1) {
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340 ngx_log_error(NGX_LOG_ALERT, log, ngx_errno, "semctl(SETVAL) failed");
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341
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342 if (semctl(m->semid, 0, IPC_RMID) == -1) {
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343 ngx_log_error(NGX_LOG_ALERT, log, ngx_errno,
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344 "semctl(IPC_RMID) failed");
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345 }
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346
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347 return NULL;
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348 }
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349
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350 return m;
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351 }
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352
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353
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112
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354 void
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355 ngx_mutex_destroy(ngx_mutex_t *m)
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0
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356 {
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357 if (semctl(m->semid, 0, IPC_RMID) == -1) {
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358 ngx_log_error(NGX_LOG_ALERT, m->log, ngx_errno,
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359 "semctl(IPC_RMID) failed");
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360 }
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361
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362 ngx_free((void *) m);
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363 }
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364
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365
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112
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366 ngx_int_t
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367 ngx_mutex_dolock(ngx_mutex_t *m, ngx_int_t try)
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0
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368 {
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50
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369 uint32_t lock, old;
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0
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370 ngx_uint_t tries;
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371 struct sembuf op;
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372
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373 if (!ngx_threaded) {
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374 return NGX_OK;
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375 }
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376
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377 #if (NGX_DEBUG)
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378 if (try) {
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379 ngx_log_debug2(NGX_LOG_DEBUG_MUTEX, m->log, 0,
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10
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380 "try lock mutex %p lock:%XD", m, m->lock);
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0
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381 } else {
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382 ngx_log_debug2(NGX_LOG_DEBUG_MUTEX, m->log, 0,
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10
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383 "lock mutex %p lock:%XD", m, m->lock);
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0
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384 }
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385 #endif
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386
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387 old = m->lock;
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388 tries = 0;
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389
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390 for ( ;; ) {
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391 if (old & NGX_MUTEX_LOCK_BUSY) {
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392
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393 if (try) {
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394 return NGX_AGAIN;
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395 }
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396
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18
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397 if (ngx_ncpu > 1 && tries++ < 1000) {
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0
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398
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399 /* the spinlock is used only on the SMP system */
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400
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401 old = m->lock;
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402 continue;
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403 }
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404
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405 if (m->semid == -1) {
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406 sched_yield();
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407
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408 tries = 0;
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409 old = m->lock;
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410 continue;
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411 }
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412
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413 ngx_log_debug2(NGX_LOG_DEBUG_MUTEX, m->log, 0,
|
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10
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414 "mutex %p lock:%XD", m, m->lock);
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0
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415
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416 /*
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|
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417 * The mutex is locked so we increase a number
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|
|
418 * of the threads that are waiting on the mutex
|
|
|
419 */
|
|
|
420
|
|
|
421 lock = old + 1;
|
|
|
422
|
|
|
423 if ((lock & ~NGX_MUTEX_LOCK_BUSY) > nthreads) {
|
|
|
424 ngx_log_error(NGX_LOG_ALERT, m->log, ngx_errno,
|
|
10
|
425 "%D threads wait for mutex %p, "
|
|
|
426 "while only %ui threads are available",
|
|
0
|
427 lock & ~NGX_MUTEX_LOCK_BUSY, m, nthreads);
|
|
112
|
428 ngx_abort();
|
|
0
|
429 }
|
|
|
430
|
|
|
431 if (ngx_atomic_cmp_set(&m->lock, old, lock)) {
|
|
|
432
|
|
|
433 ngx_log_debug2(NGX_LOG_DEBUG_MUTEX, m->log, 0,
|
|
10
|
434 "wait mutex %p lock:%XD", m, m->lock);
|
|
0
|
435
|
|
|
436 /*
|
|
|
437 * The number of the waiting threads has been increased
|
|
|
438 * and we would wait on the SysV semaphore.
|
|
|
439 * A semaphore should wake up us more efficiently than
|
|
|
440 * a simple sched_yield() or usleep().
|
|
|
441 */
|
|
|
442
|
|
|
443 op.sem_num = 0;
|
|
|
444 op.sem_op = -1;
|
|
|
445 op.sem_flg = 0;
|
|
|
446
|
|
|
447 if (semop(m->semid, &op, 1) == -1) {
|
|
|
448 ngx_log_error(NGX_LOG_ALERT, m->log, ngx_errno,
|
|
10
|
449 "semop() failed while waiting on mutex %p", m);
|
|
112
|
450 ngx_abort();
|
|
0
|
451 }
|
|
|
452
|
|
|
453 ngx_log_debug2(NGX_LOG_DEBUG_MUTEX, m->log, 0,
|
|
10
|
454 "mutex waked up %p lock:%XD", m, m->lock);
|
|
0
|
455
|
|
|
456 tries = 0;
|
|
|
457 old = m->lock;
|
|
|
458 continue;
|
|
|
459 }
|
|
|
460
|
|
|
461 old = m->lock;
|
|
|
462
|
|
|
463 } else {
|
|
|
464 lock = old | NGX_MUTEX_LOCK_BUSY;
|
|
|
465
|
|
|
466 if (ngx_atomic_cmp_set(&m->lock, old, lock)) {
|
|
|
467
|
|
|
468 /* we locked the mutex */
|
|
|
469
|
|
|
470 break;
|
|
|
471 }
|
|
|
472
|
|
|
473 old = m->lock;
|
|
|
474 }
|
|
|
475
|
|
|
476 if (tries++ > 1000) {
|
|
|
477
|
|
|
478 ngx_log_debug1(NGX_LOG_DEBUG_MUTEX, m->log, 0,
|
|
10
|
479 "mutex %p is contested", m);
|
|
0
|
480
|
|
|
481 /* the mutex is probably contested so we are giving up now */
|
|
|
482
|
|
|
483 sched_yield();
|
|
|
484
|
|
|
485 tries = 0;
|
|
|
486 old = m->lock;
|
|
|
487 }
|
|
|
488 }
|
|
|
489
|
|
|
490 ngx_log_debug2(NGX_LOG_DEBUG_MUTEX, m->log, 0,
|
|
10
|
491 "mutex %p is locked, lock:%XD", m, m->lock);
|
|
0
|
492
|
|
|
493 return NGX_OK;
|
|
|
494 }
|
|
|
495
|
|
|
496
|
|
112
|
497 void
|
|
|
498 ngx_mutex_unlock(ngx_mutex_t *m)
|
|
0
|
499 {
|
|
50
|
500 uint32_t lock, old;
|
|
0
|
501 struct sembuf op;
|
|
|
502
|
|
|
503 if (!ngx_threaded) {
|
|
112
|
504 return;
|
|
0
|
505 }
|
|
|
506
|
|
|
507 old = m->lock;
|
|
|
508
|
|
|
509 if (!(old & NGX_MUTEX_LOCK_BUSY)) {
|
|
|
510 ngx_log_error(NGX_LOG_ALERT, m->log, 0,
|
|
10
|
511 "trying to unlock the free mutex %p", m);
|
|
112
|
512 ngx_abort();
|
|
0
|
513 }
|
|
|
514
|
|
|
515 /* free the mutex */
|
|
|
516
|
|
|
517 #if 0
|
|
|
518 ngx_log_debug2(NGX_LOG_DEBUG_MUTEX, m->log, 0,
|
|
10
|
519 "unlock mutex %p lock:%XD", m, old);
|
|
0
|
520 #endif
|
|
|
521
|
|
|
522 for ( ;; ) {
|
|
|
523 lock = old & ~NGX_MUTEX_LOCK_BUSY;
|
|
|
524
|
|
|
525 if (ngx_atomic_cmp_set(&m->lock, old, lock)) {
|
|
|
526 break;
|
|
|
527 }
|
|
|
528
|
|
|
529 old = m->lock;
|
|
|
530 }
|
|
|
531
|
|
|
532 if (m->semid == -1) {
|
|
|
533 ngx_log_debug1(NGX_LOG_DEBUG_MUTEX, m->log, 0,
|
|
10
|
534 "mutex %p is unlocked", m);
|
|
0
|
535
|
|
112
|
536 return;
|
|
0
|
537 }
|
|
|
538
|
|
|
539 /* check whether we need to wake up a waiting thread */
|
|
|
540
|
|
|
541 old = m->lock;
|
|
|
542
|
|
|
543 for ( ;; ) {
|
|
|
544 if (old & NGX_MUTEX_LOCK_BUSY) {
|
|
|
545
|
|
|
546 /* the mutex is just locked by another thread */
|
|
|
547
|
|
|
548 break;
|
|
|
549 }
|
|
|
550
|
|
|
551 if (old == 0) {
|
|
|
552 break;
|
|
|
553 }
|
|
|
554
|
|
|
555 /* there are the waiting threads */
|
|
|
556
|
|
|
557 lock = old - 1;
|
|
|
558
|
|
|
559 if (ngx_atomic_cmp_set(&m->lock, old, lock)) {
|
|
|
560
|
|
|
561 /* wake up the thread that waits on semaphore */
|
|
|
562
|
|
|
563 ngx_log_debug1(NGX_LOG_DEBUG_MUTEX, m->log, 0,
|
|
10
|
564 "wake up mutex %p", m);
|
|
0
|
565
|
|
|
566 op.sem_num = 0;
|
|
|
567 op.sem_op = 1;
|
|
|
568 op.sem_flg = 0;
|
|
|
569
|
|
|
570 if (semop(m->semid, &op, 1) == -1) {
|
|
|
571 ngx_log_error(NGX_LOG_ALERT, m->log, ngx_errno,
|
|
10
|
572 "semop() failed while waking up on mutex %p", m);
|
|
112
|
573 ngx_abort();
|
|
0
|
574 }
|
|
|
575
|
|
|
576 break;
|
|
|
577 }
|
|
|
578
|
|
|
579 old = m->lock;
|
|
|
580 }
|
|
|
581
|
|
|
582 ngx_log_debug1(NGX_LOG_DEBUG_MUTEX, m->log, 0,
|
|
10
|
583 "mutex %p is unlocked", m);
|
|
0
|
584
|
|
112
|
585 return;
|
|
0
|
586 }
|
|
|
587
|
|
|
588
|
|
112
|
589 ngx_cond_t *
|
|
|
590 ngx_cond_init(ngx_log_t *log)
|
|
0
|
591 {
|
|
|
592 ngx_cond_t *cv;
|
|
|
593
|
|
50
|
594 cv = ngx_alloc(sizeof(ngx_cond_t), log);
|
|
|
595 if (cv == NULL) {
|
|
0
|
596 return NULL;
|
|
|
597 }
|
|
|
598
|
|
|
599 cv->signo = NGX_CV_SIGNAL;
|
|
18
|
600 cv->tid = -1;
|
|
0
|
601 cv->log = log;
|
|
|
602 cv->kq = -1;
|
|
|
603
|
|
|
604 return cv;
|
|
|
605 }
|
|
|
606
|
|
|
607
|
|
112
|
608 void
|
|
|
609 ngx_cond_destroy(ngx_cond_t *cv)
|
|
0
|
610 {
|
|
|
611 if (close(cv->kq) == -1) {
|
|
|
612 ngx_log_error(NGX_LOG_ALERT, cv->log, ngx_errno,
|
|
|
613 "kqueue close() failed");
|
|
|
614 }
|
|
|
615
|
|
|
616 ngx_free(cv);
|
|
|
617 }
|
|
|
618
|
|
|
619
|
|
112
|
620 ngx_int_t
|
|
|
621 ngx_cond_wait(ngx_cond_t *cv, ngx_mutex_t *m)
|
|
0
|
622 {
|
|
|
623 int n;
|
|
|
624 ngx_err_t err;
|
|
|
625 struct kevent kev;
|
|
|
626 struct timespec ts;
|
|
|
627
|
|
|
628 if (cv->kq == -1) {
|
|
|
629
|
|
|
630 /*
|
|
|
631 * We have to add the EVFILT_SIGNAL filter in the rfork()ed thread.
|
|
|
632 * Otherwise the thread would not get a signal event.
|
|
|
633 *
|
|
|
634 * However, we have not to open the kqueue in the thread,
|
|
|
635 * it is simply handy do it together.
|
|
|
636 */
|
|
|
637
|
|
|
638 cv->kq = kqueue();
|
|
|
639 if (cv->kq == -1) {
|
|
|
640 ngx_log_error(NGX_LOG_ALERT, cv->log, ngx_errno, "kqueue() failed");
|
|
|
641 return NGX_ERROR;
|
|
|
642 }
|
|
|
643
|
|
|
644 ngx_log_debug2(NGX_LOG_DEBUG_CORE, cv->log, 0,
|
|
|
645 "cv kq:%d signo:%d", cv->kq, cv->signo);
|
|
|
646
|
|
|
647 kev.ident = cv->signo;
|
|
|
648 kev.filter = EVFILT_SIGNAL;
|
|
|
649 kev.flags = EV_ADD;
|
|
|
650 kev.fflags = 0;
|
|
|
651 kev.data = 0;
|
|
|
652 kev.udata = NULL;
|
|
|
653
|
|
|
654 ts.tv_sec = 0;
|
|
|
655 ts.tv_nsec = 0;
|
|
|
656
|
|
|
657 if (kevent(cv->kq, &kev, 1, NULL, 0, &ts) == -1) {
|
|
|
658 ngx_log_error(NGX_LOG_ALERT, cv->log, ngx_errno, "kevent() failed");
|
|
|
659 return NGX_ERROR;
|
|
|
660 }
|
|
18
|
661
|
|
|
662 cv->tid = ngx_thread_self();
|
|
0
|
663 }
|
|
|
664
|
|
112
|
665 ngx_mutex_unlock(m);
|
|
0
|
666
|
|
|
667 ngx_log_debug3(NGX_LOG_DEBUG_CORE, cv->log, 0,
|
|
10
|
668 "cv %p wait, kq:%d, signo:%d", cv, cv->kq, cv->signo);
|
|
0
|
669
|
|
|
670 for ( ;; ) {
|
|
|
671 n = kevent(cv->kq, NULL, 0, &kev, 1, NULL);
|
|
|
672
|
|
|
673 ngx_log_debug2(NGX_LOG_DEBUG_CORE, cv->log, 0,
|
|
10
|
674 "cv %p kevent: %d", cv, n);
|
|
0
|
675
|
|
|
676 if (n == -1) {
|
|
|
677 err = ngx_errno;
|
|
|
678 ngx_log_error((err == NGX_EINTR) ? NGX_LOG_INFO : NGX_LOG_ALERT,
|
|
|
679 cv->log, ngx_errno,
|
|
10
|
680 "kevent() failed while waiting condition variable %p",
|
|
|
681 cv);
|
|
0
|
682
|
|
|
683 if (err == NGX_EINTR) {
|
|
|
684 break;
|
|
|
685 }
|
|
|
686
|
|
|
687 return NGX_ERROR;
|
|
|
688 }
|
|
|
689
|
|
|
690 if (n == 0) {
|
|
|
691 ngx_log_error(NGX_LOG_ALERT, cv->log, 0,
|
|
|
692 "kevent() returned no events "
|
|
10
|
693 "while waiting condition variable %p",
|
|
0
|
694 cv);
|
|
|
695 continue;
|
|
|
696 }
|
|
|
697
|
|
|
698 if (kev.filter != EVFILT_SIGNAL) {
|
|
|
699 ngx_log_error(NGX_LOG_ALERT, cv->log, 0,
|
|
|
700 "kevent() returned unexpected events: %d "
|
|
10
|
701 "while waiting condition variable %p",
|
|
0
|
702 kev.filter, cv);
|
|
|
703 continue;
|
|
|
704 }
|
|
|
705
|
|
|
706 if (kev.ident != (uintptr_t) cv->signo) {
|
|
|
707 ngx_log_error(NGX_LOG_ALERT, cv->log, 0,
|
|
|
708 "kevent() returned unexpected signal: %d ",
|
|
10
|
709 "while waiting condition variable %p",
|
|
0
|
710 kev.ident, cv);
|
|
|
711 continue;
|
|
|
712 }
|
|
|
713
|
|
|
714 break;
|
|
|
715 }
|
|
|
716
|
|
10
|
717 ngx_log_debug1(NGX_LOG_DEBUG_CORE, cv->log, 0, "cv %p is waked up", cv);
|
|
0
|
718
|
|
112
|
719 ngx_mutex_lock(m);
|
|
0
|
720
|
|
|
721 return NGX_OK;
|
|
|
722 }
|
|
|
723
|
|
|
724
|
|
112
|
725 ngx_int_t
|
|
|
726 ngx_cond_signal(ngx_cond_t *cv)
|
|
0
|
727 {
|
|
|
728 ngx_err_t err;
|
|
|
729
|
|
|
730 ngx_log_debug3(NGX_LOG_DEBUG_CORE, cv->log, 0,
|
|
10
|
731 "cv %p to signal %P %d",
|
|
0
|
732 cv, cv->tid, cv->signo);
|
|
|
733
|
|
18
|
734 if (cv->tid == -1) {
|
|
|
735 return NGX_OK;
|
|
|
736 }
|
|
|
737
|
|
0
|
738 if (kill(cv->tid, cv->signo) == -1) {
|
|
|
739
|
|
|
740 err = ngx_errno;
|
|
|
741
|
|
|
742 ngx_log_error(NGX_LOG_ALERT, cv->log, err,
|
|
10
|
743 "kill() failed while signaling condition variable %p", cv);
|
|
0
|
744
|
|
|
745 if (err == NGX_ESRCH) {
|
|
|
746 cv->tid = -1;
|
|
|
747 }
|
|
|
748
|
|
|
749 return NGX_ERROR;
|
|
|
750 }
|
|
|
751
|
|
10
|
752 ngx_log_debug1(NGX_LOG_DEBUG_CORE, cv->log, 0, "cv %p is signaled", cv);
|
|
0
|
753
|
|
|
754 return NGX_OK;
|
|
|
755 }
|
