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