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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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660
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4 * Copyright (C) Nginx, Inc.
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0
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5 */
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6
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7
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8 #include <ngx_config.h>
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9 #include <ngx_core.h>
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10
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11 /*
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12 * The threads implementation uses the rfork(RFPROC|RFTHREAD|RFMEM) syscall
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13 * to create threads. All threads use the stacks of the same size mmap()ed
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670
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14 * below the main stack. Thus the current thread id is determined via
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0
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15 * the stack pointer value.
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16 *
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17 * The mutex implementation uses the ngx_atomic_cmp_set() operation
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18 * to acquire a mutex and the SysV semaphore to wait on a mutex and to wake up
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19 * the waiting threads. The light mutex does not use semaphore, so after
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20 * spinning in the lock the thread calls sched_yield(). However the light
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670
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21 * mutexes are intended to be used with the "trylock" operation only.
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0
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22 * The SysV semop() is a cheap syscall, particularly if it has little sembuf's
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23 * and does not use SEM_UNDO.
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24 *
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10
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25 * The condition variable implementation uses the signal #64.
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26 * The signal handler is SIG_IGN so the kill() is a cheap syscall.
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27 * The thread waits a signal in kevent(). The use of the EVFILT_SIGNAL
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28 * is safe since FreeBSD 4.10-STABLE.
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0
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29 *
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30 * This threads implementation currently works on i386 (486+) and amd64
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31 * platforms only.
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32 */
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33
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34
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35 char *ngx_freebsd_kern_usrstack;
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36 size_t ngx_thread_stack_size;
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37
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38
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39 static size_t rz_size;
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40 static size_t usable_stack_size;
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41 static char *last_stack;
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42
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43 static ngx_uint_t nthreads;
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44 static ngx_uint_t max_threads;
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45
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46 static ngx_uint_t nkeys;
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47 static ngx_tid_t *tids; /* the threads tids array */
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48 void **ngx_tls; /* the threads tls's array */
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49
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50 /* the thread-safe libc errno */
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51
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52 static int errno0; /* the main thread's errno */
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53 static int *errnos; /* the threads errno's array */
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54
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112
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55 int *
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56 __error()
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0
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57 {
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58 int tid;
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59
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60 tid = ngx_gettid();
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61
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62 return tid ? &errnos[tid - 1] : &errno0;
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63 }
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64
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65
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66 /*
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67 * __isthreaded enables the spinlocks in some libc functions, i.e. in malloc()
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68 * and some other places. Nevertheless we protect our malloc()/free() calls
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69 * by own mutex that is more efficient than the spinlock.
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70 *
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71 * _spinlock() is a weak referenced stub in src/lib/libc/gen/_spinlock_stub.c
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72 * that does nothing.
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73 */
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74
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75 extern int __isthreaded;
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76
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112
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77 void
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78 _spinlock(ngx_atomic_t *lock)
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0
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79 {
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80 ngx_int_t tries;
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81
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82 tries = 0;
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83
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84 for ( ;; ) {
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85
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86 if (*lock) {
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87 if (ngx_ncpu > 1 && tries++ < 1000) {
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88 continue;
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89 }
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90
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91 sched_yield();
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92 tries = 0;
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93
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94 } else {
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95 if (ngx_atomic_cmp_set(lock, 0, 1)) {
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96 return;
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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 /*
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104 * Before FreeBSD 5.1 _spinunlock() is a simple #define in
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105 * src/lib/libc/include/spinlock.h that zeroes lock.
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106 *
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107 * Since FreeBSD 5.1 _spinunlock() is a weak referenced stub in
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108 * src/lib/libc/gen/_spinlock_stub.c that does nothing.
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109 */
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110
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111 #ifndef _spinunlock
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112
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112
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113 void
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114 _spinunlock(ngx_atomic_t *lock)
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0
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115 {
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116 *lock = 0;
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117 }
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118
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119 #endif
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120
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121
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112
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122 ngx_err_t
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123 ngx_create_thread(ngx_tid_t *tid, ngx_thread_value_t (*func)(void *arg),
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124 void *arg, ngx_log_t *log)
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0
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125 {
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10
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126 ngx_pid_t id;
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127 ngx_err_t err;
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128 char *stack, *stack_top;
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0
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129
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130 if (nthreads >= max_threads) {
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131 ngx_log_error(NGX_LOG_CRIT, log, 0,
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10
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132 "no more than %ui threads can be created", max_threads);
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0
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133 return NGX_ERROR;
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134 }
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135
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136 last_stack -= ngx_thread_stack_size;
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137
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138 stack = mmap(last_stack, usable_stack_size, PROT_READ|PROT_WRITE,
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139 MAP_STACK, -1, 0);
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140
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141 if (stack == MAP_FAILED) {
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142 ngx_log_error(NGX_LOG_ALERT, log, ngx_errno,
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10
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143 "mmap(%p:%uz, MAP_STACK) thread stack failed",
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0
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144 last_stack, usable_stack_size);
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145 return NGX_ERROR;
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146 }
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147
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148 if (stack != last_stack) {
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10
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149 ngx_log_error(NGX_LOG_ALERT, log, 0,
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150 "stack %p address was changed to %p", last_stack, stack);
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151 return NGX_ERROR;
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0
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152 }
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153
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154 stack_top = stack + usable_stack_size;
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155
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156 ngx_log_debug2(NGX_LOG_DEBUG_CORE, log, 0,
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157 "thread stack: %p-%p", stack, stack_top);
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0
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158
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159 ngx_set_errno(0);
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160
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161 id = rfork_thread(RFPROC|RFTHREAD|RFMEM, stack_top,
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162 (ngx_rfork_thread_func_pt) func, arg);
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163
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164 err = ngx_errno;
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165
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166 if (id == -1) {
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167 ngx_log_error(NGX_LOG_ALERT, log, err, "rfork() failed");
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168
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169 } else {
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170 *tid = id;
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171 nthreads = (ngx_freebsd_kern_usrstack - stack_top)
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172 / ngx_thread_stack_size;
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173 tids[nthreads] = id;
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174
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10
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175 ngx_log_debug1(NGX_LOG_DEBUG_CORE, log, 0, "rfork()ed thread: %P", id);
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0
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176 }
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177
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178 return err;
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179 }
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180
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181
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112
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182 ngx_int_t
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183 ngx_init_threads(int n, size_t size, ngx_cycle_t *cycle)
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0
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184 {
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185 char *red_zone, *zone;
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186 size_t len;
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187 ngx_int_t i;
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188 struct sigaction sa;
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189
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190 max_threads = n + 1;
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191
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192 for (i = 0; i < n; i++) {
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193 ngx_memzero(&sa, sizeof(struct sigaction));
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194 sa.sa_handler = SIG_IGN;
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195 sigemptyset(&sa.sa_mask);
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196 if (sigaction(NGX_CV_SIGNAL, &sa, NULL) == -1) {
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197 ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
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198 "sigaction(%d, SIG_IGN) failed", NGX_CV_SIGNAL);
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199 return NGX_ERROR;
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200 }
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201 }
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202
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203 len = sizeof(ngx_freebsd_kern_usrstack);
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204 if (sysctlbyname("kern.usrstack", &ngx_freebsd_kern_usrstack, &len,
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205 NULL, 0) == -1)
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206 {
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207 ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
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208 "sysctlbyname(kern.usrstack) failed");
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209 return NGX_ERROR;
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210 }
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211
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212 /* the main thread stack red zone */
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213 rz_size = ngx_pagesize;
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214 red_zone = ngx_freebsd_kern_usrstack - (size + rz_size);
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215
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216 ngx_log_debug2(NGX_LOG_DEBUG_CORE, cycle->log, 0,
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10
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217 "usrstack: %p red zone: %p",
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0
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218 ngx_freebsd_kern_usrstack, red_zone);
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219
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220 zone = mmap(red_zone, rz_size, PROT_NONE, MAP_ANON, -1, 0);
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221 if (zone == MAP_FAILED) {
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222 ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
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10
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223 "mmap(%p:%uz, PROT_NONE, MAP_ANON) red zone failed",
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0
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224 red_zone, rz_size);
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225 return NGX_ERROR;
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226 }
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227
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228 if (zone != red_zone) {
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229 ngx_log_error(NGX_LOG_ALERT, cycle->log, 0,
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10
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230 "red zone %p address was changed to %p", red_zone, zone);
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231 return NGX_ERROR;
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0
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232 }
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233
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10
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234 /* create the thread errno' array */
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0
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235
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50
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236 errnos = ngx_calloc(n * sizeof(int), cycle->log);
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237 if (errnos == NULL) {
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0
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238 return NGX_ERROR;
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239 }
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240
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10
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241 /* create the thread tids array */
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0
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242
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50
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243 tids = ngx_calloc((n + 1) * sizeof(ngx_tid_t), cycle->log);
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244 if (tids == NULL) {
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0
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245 return NGX_ERROR;
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246 }
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247
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248 tids[0] = ngx_pid;
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249
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10
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250 /* create the thread tls' array */
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0
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251
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252 ngx_tls = ngx_calloc(NGX_THREAD_KEYS_MAX * (n + 1) * sizeof(void *),
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253 cycle->log);
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254 if (ngx_tls == NULL) {
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255 return NGX_ERROR;
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256 }
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257
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258 nthreads = 1;
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259
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260 last_stack = zone + rz_size;
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261 usable_stack_size = size;
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262 ngx_thread_stack_size = size + rz_size;
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263
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264 /* allow the spinlock in libc malloc() */
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265 __isthreaded = 1;
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266
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267 ngx_threaded = 1;
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268
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269 return NGX_OK;
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270 }
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271
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272
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112
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273 ngx_tid_t
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274 ngx_thread_self()
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0
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275 {
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50
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276 ngx_int_t tid;
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0
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277
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278 tid = ngx_gettid();
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279
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280 if (tids == NULL) {
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281 return ngx_pid;
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282 }
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283
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284 return tids[tid];
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285 }
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286
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287
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112
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288 ngx_err_t
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289 ngx_thread_key_create(ngx_tls_key_t *key)
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0
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290 {
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291 if (nkeys >= NGX_THREAD_KEYS_MAX) {
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292 return NGX_ENOMEM;
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293 }
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294
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295 *key = nkeys++;
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296
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297 return 0;
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298 }
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299
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300
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112
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301 ngx_err_t
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302 ngx_thread_set_tls(ngx_tls_key_t key, void *value)
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0
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303 {
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304 if (key >= NGX_THREAD_KEYS_MAX) {
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305 return NGX_EINVAL;
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306 }
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307
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308 ngx_tls[key * NGX_THREAD_KEYS_MAX + ngx_gettid()] = value;
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309 return 0;
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310 }
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311
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312
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112
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313 ngx_mutex_t *
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314 ngx_mutex_init(ngx_log_t *log, ngx_uint_t flags)
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0
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315 {
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316 ngx_mutex_t *m;
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317 union semun op;
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318
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50
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319 m = ngx_alloc(sizeof(ngx_mutex_t), log);
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320 if (m == NULL) {
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0
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321 return NULL;
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322 }
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323
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324 m->lock = 0;
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325 m->log = log;
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326
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327 if (flags & NGX_MUTEX_LIGHT) {
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328 m->semid = -1;
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329 return m;
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330 }
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331
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332 m->semid = semget(IPC_PRIVATE, 1, SEM_R|SEM_A);
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333 if (m->semid == -1) {
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334 ngx_log_error(NGX_LOG_ALERT, log, ngx_errno, "semget() failed");
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335 return NULL;
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336 }
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337
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338 op.val = 0;
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339
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340 if (semctl(m->semid, 0, SETVAL, op) == -1) {
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341 ngx_log_error(NGX_LOG_ALERT, log, ngx_errno, "semctl(SETVAL) failed");
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342
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343 if (semctl(m->semid, 0, IPC_RMID) == -1) {
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344 ngx_log_error(NGX_LOG_ALERT, log, ngx_errno,
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345 "semctl(IPC_RMID) failed");
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346 }
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347
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348 return NULL;
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349 }
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350
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351 return m;
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352 }
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353
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354
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112
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355 void
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356 ngx_mutex_destroy(ngx_mutex_t *m)
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0
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357 {
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358 if (semctl(m->semid, 0, IPC_RMID) == -1) {
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359 ngx_log_error(NGX_LOG_ALERT, m->log, ngx_errno,
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360 "semctl(IPC_RMID) failed");
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361 }
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362
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363 ngx_free((void *) m);
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364 }
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365
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366
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112
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367 ngx_int_t
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368 ngx_mutex_dolock(ngx_mutex_t *m, ngx_int_t try)
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0
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369 {
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50
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370 uint32_t lock, old;
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0
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371 ngx_uint_t tries;
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372 struct sembuf op;
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373
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374 if (!ngx_threaded) {
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375 return NGX_OK;
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376 }
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377
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378 #if (NGX_DEBUG)
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379 if (try) {
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380 ngx_log_debug2(NGX_LOG_DEBUG_MUTEX, m->log, 0,
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10
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381 "try lock mutex %p lock:%XD", m, m->lock);
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0
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382 } else {
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383 ngx_log_debug2(NGX_LOG_DEBUG_MUTEX, m->log, 0,
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10
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384 "lock mutex %p lock:%XD", m, m->lock);
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0
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385 }
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386 #endif
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387
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388 old = m->lock;
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389 tries = 0;
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390
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391 for ( ;; ) {
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392 if (old & NGX_MUTEX_LOCK_BUSY) {
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393
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394 if (try) {
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395 return NGX_AGAIN;
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396 }
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397
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18
|
398 if (ngx_ncpu > 1 && tries++ < 1000) {
|
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0
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399
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400 /* the spinlock is used only on the SMP system */
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401
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402 old = m->lock;
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403 continue;
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404 }
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405
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406 if (m->semid == -1) {
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407 sched_yield();
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408
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409 tries = 0;
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410 old = m->lock;
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411 continue;
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412 }
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413
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414 ngx_log_debug2(NGX_LOG_DEBUG_MUTEX, m->log, 0,
|
|
10
|
415 "mutex %p lock:%XD", m, m->lock);
|
|
0
|
416
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|
|
417 /*
|
|
|
418 * The mutex is locked so we increase a number
|
|
|
419 * of the threads that are waiting on the mutex
|
|
|
420 */
|
|
|
421
|
|
|
422 lock = old + 1;
|
|
|
423
|
|
|
424 if ((lock & ~NGX_MUTEX_LOCK_BUSY) > nthreads) {
|
|
|
425 ngx_log_error(NGX_LOG_ALERT, m->log, ngx_errno,
|
|
10
|
426 "%D threads wait for mutex %p, "
|
|
|
427 "while only %ui threads are available",
|
|
0
|
428 lock & ~NGX_MUTEX_LOCK_BUSY, m, nthreads);
|
|
112
|
429 ngx_abort();
|
|
0
|
430 }
|
|
|
431
|
|
|
432 if (ngx_atomic_cmp_set(&m->lock, old, lock)) {
|
|
|
433
|
|
|
434 ngx_log_debug2(NGX_LOG_DEBUG_MUTEX, m->log, 0,
|
|
10
|
435 "wait mutex %p lock:%XD", m, m->lock);
|
|
0
|
436
|
|
|
437 /*
|
|
|
438 * The number of the waiting threads has been increased
|
|
|
439 * and we would wait on the SysV semaphore.
|
|
|
440 * A semaphore should wake up us more efficiently than
|
|
|
441 * a simple sched_yield() or usleep().
|
|
|
442 */
|
|
|
443
|
|
|
444 op.sem_num = 0;
|
|
|
445 op.sem_op = -1;
|
|
|
446 op.sem_flg = 0;
|
|
|
447
|
|
|
448 if (semop(m->semid, &op, 1) == -1) {
|
|
|
449 ngx_log_error(NGX_LOG_ALERT, m->log, ngx_errno,
|
|
10
|
450 "semop() failed while waiting on mutex %p", m);
|
|
112
|
451 ngx_abort();
|
|
0
|
452 }
|
|
|
453
|
|
|
454 ngx_log_debug2(NGX_LOG_DEBUG_MUTEX, m->log, 0,
|
|
10
|
455 "mutex waked up %p lock:%XD", m, m->lock);
|
|
0
|
456
|
|
|
457 tries = 0;
|
|
|
458 old = m->lock;
|
|
|
459 continue;
|
|
|
460 }
|
|
|
461
|
|
|
462 old = m->lock;
|
|
|
463
|
|
|
464 } else {
|
|
|
465 lock = old | NGX_MUTEX_LOCK_BUSY;
|
|
|
466
|
|
|
467 if (ngx_atomic_cmp_set(&m->lock, old, lock)) {
|
|
|
468
|
|
|
469 /* we locked the mutex */
|
|
|
470
|
|
|
471 break;
|
|
|
472 }
|
|
|
473
|
|
|
474 old = m->lock;
|
|
|
475 }
|
|
|
476
|
|
|
477 if (tries++ > 1000) {
|
|
|
478
|
|
|
479 ngx_log_debug1(NGX_LOG_DEBUG_MUTEX, m->log, 0,
|
|
10
|
480 "mutex %p is contested", m);
|
|
0
|
481
|
|
|
482 /* the mutex is probably contested so we are giving up now */
|
|
|
483
|
|
|
484 sched_yield();
|
|
|
485
|
|
|
486 tries = 0;
|
|
|
487 old = m->lock;
|
|
|
488 }
|
|
|
489 }
|
|
|
490
|
|
|
491 ngx_log_debug2(NGX_LOG_DEBUG_MUTEX, m->log, 0,
|
|
10
|
492 "mutex %p is locked, lock:%XD", m, m->lock);
|
|
0
|
493
|
|
|
494 return NGX_OK;
|
|
|
495 }
|
|
|
496
|
|
|
497
|
|
112
|
498 void
|
|
|
499 ngx_mutex_unlock(ngx_mutex_t *m)
|
|
0
|
500 {
|
|
50
|
501 uint32_t lock, old;
|
|
0
|
502 struct sembuf op;
|
|
|
503
|
|
|
504 if (!ngx_threaded) {
|
|
112
|
505 return;
|
|
0
|
506 }
|
|
|
507
|
|
|
508 old = m->lock;
|
|
|
509
|
|
|
510 if (!(old & NGX_MUTEX_LOCK_BUSY)) {
|
|
|
511 ngx_log_error(NGX_LOG_ALERT, m->log, 0,
|
|
10
|
512 "trying to unlock the free mutex %p", m);
|
|
112
|
513 ngx_abort();
|
|
0
|
514 }
|
|
|
515
|
|
|
516 /* free the mutex */
|
|
|
517
|
|
|
518 #if 0
|
|
|
519 ngx_log_debug2(NGX_LOG_DEBUG_MUTEX, m->log, 0,
|
|
10
|
520 "unlock mutex %p lock:%XD", m, old);
|
|
0
|
521 #endif
|
|
|
522
|
|
|
523 for ( ;; ) {
|
|
|
524 lock = old & ~NGX_MUTEX_LOCK_BUSY;
|
|
|
525
|
|
|
526 if (ngx_atomic_cmp_set(&m->lock, old, lock)) {
|
|
|
527 break;
|
|
|
528 }
|
|
|
529
|
|
|
530 old = m->lock;
|
|
|
531 }
|
|
|
532
|
|
|
533 if (m->semid == -1) {
|
|
|
534 ngx_log_debug1(NGX_LOG_DEBUG_MUTEX, m->log, 0,
|
|
10
|
535 "mutex %p is unlocked", m);
|
|
0
|
536
|
|
112
|
537 return;
|
|
0
|
538 }
|
|
|
539
|
|
|
540 /* check whether we need to wake up a waiting thread */
|
|
|
541
|
|
|
542 old = m->lock;
|
|
|
543
|
|
|
544 for ( ;; ) {
|
|
|
545 if (old & NGX_MUTEX_LOCK_BUSY) {
|
|
|
546
|
|
|
547 /* the mutex is just locked by another thread */
|
|
|
548
|
|
|
549 break;
|
|
|
550 }
|
|
|
551
|
|
|
552 if (old == 0) {
|
|
|
553 break;
|
|
|
554 }
|
|
|
555
|
|
|
556 /* there are the waiting threads */
|
|
|
557
|
|
|
558 lock = old - 1;
|
|
|
559
|
|
|
560 if (ngx_atomic_cmp_set(&m->lock, old, lock)) {
|
|
|
561
|
|
|
562 /* wake up the thread that waits on semaphore */
|
|
|
563
|
|
|
564 ngx_log_debug1(NGX_LOG_DEBUG_MUTEX, m->log, 0,
|
|
10
|
565 "wake up mutex %p", m);
|
|
0
|
566
|
|
|
567 op.sem_num = 0;
|
|
|
568 op.sem_op = 1;
|
|
|
569 op.sem_flg = 0;
|
|
|
570
|
|
|
571 if (semop(m->semid, &op, 1) == -1) {
|
|
|
572 ngx_log_error(NGX_LOG_ALERT, m->log, ngx_errno,
|
|
10
|
573 "semop() failed while waking up on mutex %p", m);
|
|
112
|
574 ngx_abort();
|
|
0
|
575 }
|
|
|
576
|
|
|
577 break;
|
|
|
578 }
|
|
|
579
|
|
|
580 old = m->lock;
|
|
|
581 }
|
|
|
582
|
|
|
583 ngx_log_debug1(NGX_LOG_DEBUG_MUTEX, m->log, 0,
|
|
10
|
584 "mutex %p is unlocked", m);
|
|
0
|
585
|
|
112
|
586 return;
|
|
0
|
587 }
|
|
|
588
|
|
|
589
|
|
112
|
590 ngx_cond_t *
|
|
|
591 ngx_cond_init(ngx_log_t *log)
|
|
0
|
592 {
|
|
|
593 ngx_cond_t *cv;
|
|
|
594
|
|
50
|
595 cv = ngx_alloc(sizeof(ngx_cond_t), log);
|
|
|
596 if (cv == NULL) {
|
|
0
|
597 return NULL;
|
|
|
598 }
|
|
|
599
|
|
|
600 cv->signo = NGX_CV_SIGNAL;
|
|
18
|
601 cv->tid = -1;
|
|
0
|
602 cv->log = log;
|
|
|
603 cv->kq = -1;
|
|
|
604
|
|
|
605 return cv;
|
|
|
606 }
|
|
|
607
|
|
|
608
|
|
112
|
609 void
|
|
|
610 ngx_cond_destroy(ngx_cond_t *cv)
|
|
0
|
611 {
|
|
|
612 if (close(cv->kq) == -1) {
|
|
|
613 ngx_log_error(NGX_LOG_ALERT, cv->log, ngx_errno,
|
|
|
614 "kqueue close() failed");
|
|
|
615 }
|
|
|
616
|
|
|
617 ngx_free(cv);
|
|
|
618 }
|
|
|
619
|
|
|
620
|
|
112
|
621 ngx_int_t
|
|
|
622 ngx_cond_wait(ngx_cond_t *cv, ngx_mutex_t *m)
|
|
0
|
623 {
|
|
|
624 int n;
|
|
|
625 ngx_err_t err;
|
|
|
626 struct kevent kev;
|
|
|
627 struct timespec ts;
|
|
|
628
|
|
|
629 if (cv->kq == -1) {
|
|
|
630
|
|
|
631 /*
|
|
|
632 * We have to add the EVFILT_SIGNAL filter in the rfork()ed thread.
|
|
|
633 * Otherwise the thread would not get a signal event.
|
|
|
634 *
|
|
|
635 * However, we have not to open the kqueue in the thread,
|
|
|
636 * it is simply handy do it together.
|
|
|
637 */
|
|
|
638
|
|
|
639 cv->kq = kqueue();
|
|
|
640 if (cv->kq == -1) {
|
|
|
641 ngx_log_error(NGX_LOG_ALERT, cv->log, ngx_errno, "kqueue() failed");
|
|
|
642 return NGX_ERROR;
|
|
|
643 }
|
|
|
644
|
|
|
645 ngx_log_debug2(NGX_LOG_DEBUG_CORE, cv->log, 0,
|
|
|
646 "cv kq:%d signo:%d", cv->kq, cv->signo);
|
|
|
647
|
|
|
648 kev.ident = cv->signo;
|
|
|
649 kev.filter = EVFILT_SIGNAL;
|
|
|
650 kev.flags = EV_ADD;
|
|
|
651 kev.fflags = 0;
|
|
|
652 kev.data = 0;
|
|
|
653 kev.udata = NULL;
|
|
|
654
|
|
|
655 ts.tv_sec = 0;
|
|
|
656 ts.tv_nsec = 0;
|
|
|
657
|
|
|
658 if (kevent(cv->kq, &kev, 1, NULL, 0, &ts) == -1) {
|
|
|
659 ngx_log_error(NGX_LOG_ALERT, cv->log, ngx_errno, "kevent() failed");
|
|
|
660 return NGX_ERROR;
|
|
|
661 }
|
|
18
|
662
|
|
|
663 cv->tid = ngx_thread_self();
|
|
0
|
664 }
|
|
|
665
|
|
112
|
666 ngx_mutex_unlock(m);
|
|
0
|
667
|
|
|
668 ngx_log_debug3(NGX_LOG_DEBUG_CORE, cv->log, 0,
|
|
10
|
669 "cv %p wait, kq:%d, signo:%d", cv, cv->kq, cv->signo);
|
|
0
|
670
|
|
|
671 for ( ;; ) {
|
|
|
672 n = kevent(cv->kq, NULL, 0, &kev, 1, NULL);
|
|
|
673
|
|
|
674 ngx_log_debug2(NGX_LOG_DEBUG_CORE, cv->log, 0,
|
|
10
|
675 "cv %p kevent: %d", cv, n);
|
|
0
|
676
|
|
|
677 if (n == -1) {
|
|
|
678 err = ngx_errno;
|
|
|
679 ngx_log_error((err == NGX_EINTR) ? NGX_LOG_INFO : NGX_LOG_ALERT,
|
|
|
680 cv->log, ngx_errno,
|
|
10
|
681 "kevent() failed while waiting condition variable %p",
|
|
|
682 cv);
|
|
0
|
683
|
|
|
684 if (err == NGX_EINTR) {
|
|
|
685 break;
|
|
|
686 }
|
|
|
687
|
|
|
688 return NGX_ERROR;
|
|
|
689 }
|
|
|
690
|
|
|
691 if (n == 0) {
|
|
|
692 ngx_log_error(NGX_LOG_ALERT, cv->log, 0,
|
|
|
693 "kevent() returned no events "
|
|
10
|
694 "while waiting condition variable %p",
|
|
0
|
695 cv);
|
|
|
696 continue;
|
|
|
697 }
|
|
|
698
|
|
|
699 if (kev.filter != EVFILT_SIGNAL) {
|
|
|
700 ngx_log_error(NGX_LOG_ALERT, cv->log, 0,
|
|
|
701 "kevent() returned unexpected events: %d "
|
|
10
|
702 "while waiting condition variable %p",
|
|
0
|
703 kev.filter, cv);
|
|
|
704 continue;
|
|
|
705 }
|
|
|
706
|
|
|
707 if (kev.ident != (uintptr_t) cv->signo) {
|
|
|
708 ngx_log_error(NGX_LOG_ALERT, cv->log, 0,
|
|
|
709 "kevent() returned unexpected signal: %d ",
|
|
10
|
710 "while waiting condition variable %p",
|
|
0
|
711 kev.ident, cv);
|
|
|
712 continue;
|
|
|
713 }
|
|
|
714
|
|
|
715 break;
|
|
|
716 }
|
|
|
717
|
|
10
|
718 ngx_log_debug1(NGX_LOG_DEBUG_CORE, cv->log, 0, "cv %p is waked up", cv);
|
|
0
|
719
|
|
112
|
720 ngx_mutex_lock(m);
|
|
0
|
721
|
|
|
722 return NGX_OK;
|
|
|
723 }
|
|
|
724
|
|
|
725
|
|
112
|
726 ngx_int_t
|
|
|
727 ngx_cond_signal(ngx_cond_t *cv)
|
|
0
|
728 {
|
|
|
729 ngx_err_t err;
|
|
|
730
|
|
|
731 ngx_log_debug3(NGX_LOG_DEBUG_CORE, cv->log, 0,
|
|
10
|
732 "cv %p to signal %P %d",
|
|
0
|
733 cv, cv->tid, cv->signo);
|
|
|
734
|
|
18
|
735 if (cv->tid == -1) {
|
|
|
736 return NGX_OK;
|
|
|
737 }
|
|
|
738
|
|
0
|
739 if (kill(cv->tid, cv->signo) == -1) {
|
|
|
740
|
|
|
741 err = ngx_errno;
|
|
|
742
|
|
|
743 ngx_log_error(NGX_LOG_ALERT, cv->log, err,
|
|
10
|
744 "kill() failed while signaling condition variable %p", cv);
|
|
0
|
745
|
|
|
746 if (err == NGX_ESRCH) {
|
|
|
747 cv->tid = -1;
|
|
|
748 }
|
|
|
749
|
|
|
750 return NGX_ERROR;
|
|
|
751 }
|
|
|
752
|
|
10
|
753 ngx_log_debug1(NGX_LOG_DEBUG_CORE, cv->log, 0, "cv %p is signaled", cv);
|
|
0
|
754
|
|
|
755 return NGX_OK;
|
|
|
756 }
|
