void
ngx_time_sigsafe_update(void)
{
u_char *p, *p2;
ngx_tm_t tm;
time_t sec;
ngx_time_t *tp;
struct timeval tv;
if (!ngx_trylock(&ngx_time_lock)) {
return;
}
ngx_gettimeofday(&tv);
sec = tv.tv_sec;
tp = &cached_time[slot];
if (tp->sec == sec) {
ngx_unlock(&ngx_time_lock);
return;
}
if (slot == NGX_TIME_SLOTS - 1) {
slot = 0;
} else {
slot++;
}
tp = &cached_time[slot];
tp->sec = 0;
ngx_gmtime(sec + cached_gmtoff * 60, &tm);
p = &cached_err_log_time[slot][0];
(void) ngx_sprintf(p, "%4d/%02d/%02d %02d:%02d:%02d",
tm.ngx_tm_year, tm.ngx_tm_mon,
tm.ngx_tm_mday, tm.ngx_tm_hour,
tm.ngx_tm_min, tm.ngx_tm_sec);
p2 = &cached_syslog_time[slot][0];
(void) ngx_sprintf(p2, "%s %2d %02d:%02d:%02d",
months[tm.ngx_tm_mon - 1], tm.ngx_tm_mday,
tm.ngx_tm_hour, tm.ngx_tm_min, tm.ngx_tm_sec);
ngx_memory_barrier();
ngx_cached_err_log_time.data = p;
ngx_cached_syslog_time.data = p2;
ngx_unlock(&ngx_time_lock);
}
//任务处理完后，epoll的通知读事件会调用该函数
////ngx_notify通告主线程，该任务处理完毕，ngx_thread_pool_handler由主线程执行，也就是进程cycle{}通过epoll_wait返回执行，而不是由线程池中的线程执行
static void
ngx_thread_pool_handler(ngx_event_t *ev)
{
ngx_event_t *event;
ngx_thread_task_t *task;
ngx_log_debug0(NGX_LOG_DEBUG_CORE, ev->log, 0, "thread pool handler");
ngx_spinlock(&ngx_thread_pool_done_lock, 1, 2048);
/* 这里是不是有问题?
如果线程池中的线程执行任务比较快，而主进程在执行epoll_wait过程中有点阻塞，那么就检测不到ngx_notify中的epoll事件，有可能下次检测到该事件的时候
ngx_thread_pool_done上已经积累了很多执行完的任务事件，见ngx_thread_pool_cycle。
单这里好像只取了队列首部的任务啊?????? 队首外的任务丢弃了???????????不对吧
答案是，这里面所有的任务都在下面的while{}中得到了执行
*/
task = ngx_thread_pool_done.first;
ngx_thread_pool_done.first = NULL;
//尾部指向头，但是头已经变为空，即不执行任务
ngx_thread_pool_done.last = &ngx_thread_pool_done.first;
ngx_unlock(&ngx_thread_pool_done_lock);
while (task) {//遍历执行前面队列ngx_thread_pool_done中的每一个任务
ngx_log_debug1(NGX_LOG_DEBUG_CORE, ev->log, 0,
"run completion handler for task #%ui", task->id);
event = &task->event;
task = task->next;
event->complete = 1;
event->active = 0;
/*如果是小文件，则一次可以读完，函数指向可以参考ngx_http_cache_thread_handler ngx_http_copy_thread_handler ngx_thread_read
如果是大文件下载，则第一次走这里函数式上面的几个函数，但是由于一次最多获取32768字节，因此需要多次读取文件，就是由一次tread执行完任务后
触发ngx_notify通道epoll，然后走到这里继续读
*/
event->handler(event);//这里是否应该检查event->handler是否为空，例如参考ngx_thread_pool_destroy
}
}
static void
ngx_thread_pool_handler(ngx_event_t *ev)
{
ngx_event_t *event;
ngx_thread_task_t *task;
ngx_log_debug0(NGX_LOG_DEBUG_CORE, ev->log, 0, "thread pool handler");
ngx_spinlock(&ngx_thread_pool_done_lock, 1, 2048);
task = ngx_thread_pool_done.first;
ngx_thread_pool_done.first = NULL;
ngx_thread_pool_done.last = &ngx_thread_pool_done.first;
ngx_unlock(&ngx_thread_pool_done_lock);
while (task)
{
ngx_log_debug1(NGX_LOG_DEBUG_CORE, ev->log, 0,
"run completion handler for task #%ui", task->id);
event = &task->event;
task = task->next;
event->complete = 1;
event->active = 0;
event->handler(event);
}
}
ngx_int_t
ngx_event_thread_process_posted(ngx_cycle_t *cycle)
{
ngx_event_t *ev;
for ( ;; ) {
ev = (ngx_event_t *) ngx_posted_events;
for ( ;; ) {
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
"posted event %p", ev);
if (ev == NULL) {
return NGX_OK;
}
if (ngx_trylock(ev->lock) == 0) {
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
"posted event %p is busy", ev);
ev = ev->next;
continue;
}
if (ev->lock != ev->own_lock) {
if (*(ev->own_lock)) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, 0,
"the own lock of the posted event %p is busy", ev);
ngx_unlock(ev->lock);
ev = ev->next;
continue;
}
*(ev->own_lock) = 1;
}
ngx_delete_posted_event(ev);
ev->locked = 1;
ev->ready |= ev->posted_ready;
ev->timedout |= ev->posted_timedout;
ev->pending_eof |= ev->posted_eof;
#if (NGX_HAVE_KQUEUE)
ev->kq_errno |= ev->posted_errno;
#endif
if (ev->posted_available) {
ev->available = ev->posted_available;
}
ev->posted_ready = 0;
ev->posted_timedout = 0;
ev->posted_eof = 0;
#if (NGX_HAVE_KQUEUE)
ev->posted_errno = 0;
#endif
ev->posted_available = 0;
ngx_mutex_unlock(ngx_posted_events_mutex);
ev->handler(ev);
ngx_mutex_lock(ngx_posted_events_mutex);
if (ev->locked) {
ngx_unlock(ev->lock);
if (ev->lock != ev->own_lock) {
ngx_unlock(ev->own_lock);
}
}
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
"posted event %p is done", ev);
break;
}
}
}
void
ngx_time_update(void)
{
u_char *p0, *p1, *p2, *p3;
ngx_tm_t tm, gmt;
time_t sec;
ngx_uint_t msec;
ngx_time_t *tp;
struct timeval tv;
if (!ngx_trylock(&ngx_time_lock)) {
return;
}
ngx_gettimeofday(&tv);
sec = tv.tv_sec;
msec = tv.tv_usec / 1000;
ngx_current_msec = (ngx_msec_t) sec * 1000 + msec;
tp = &cached_time[slot];
if (tp->sec == sec) {
tp->msec = msec;
ngx_unlock(&ngx_time_lock);
return;
}
if (slot == NGX_TIME_SLOTS - 1) {
slot = 0;
} else {
slot++;
}
tp = &cached_time[slot];
tp->sec = sec;
tp->msec = msec;
ngx_gmtime(sec, &gmt);
p0 = &cached_http_time[slot][0];
(void) ngx_sprintf(p0, "%s, %02d %s %4d %02d:%02d:%02d GMT",
week[gmt.ngx_tm_wday], gmt.ngx_tm_mday,
months[gmt.ngx_tm_mon - 1], gmt.ngx_tm_year,
gmt.ngx_tm_hour, gmt.ngx_tm_min, gmt.ngx_tm_sec);
#if (NGX_HAVE_GETTIMEZONE)
tp->gmtoff = ngx_gettimezone();
ngx_gmtime(sec + tp->gmtoff * 60, &tm);
#elif (NGX_HAVE_GMTOFF)
ngx_localtime(sec, &tm);
cached_gmtoff = (ngx_int_t) (tm.ngx_tm_gmtoff / 60);
tp->gmtoff = cached_gmtoff;
#else
ngx_localtime(sec, &tm);
cached_gmtoff = ngx_timezone(tm.ngx_tm_isdst);
tp->gmtoff = cached_gmtoff;
#endif
p1 = &cached_err_log_time[slot][0];
(void) ngx_sprintf(p1, "%4d/%02d/%02d %02d:%02d:%02d",
tm.ngx_tm_year, tm.ngx_tm_mon,
tm.ngx_tm_mday, tm.ngx_tm_hour,
tm.ngx_tm_min, tm.ngx_tm_sec);
p2 = &cached_http_log_time[slot][0];
(void) ngx_sprintf(p2, "%02d/%s/%d:%02d:%02d:%02d %c%02d%02d",
tm.ngx_tm_mday, months[tm.ngx_tm_mon - 1],
tm.ngx_tm_year, tm.ngx_tm_hour,
tm.ngx_tm_min, tm.ngx_tm_sec,
tp->gmtoff < 0 ? '-' : '+',
ngx_abs(tp->gmtoff / 60), ngx_abs(tp->gmtoff % 60));
p3 = &cached_http_log_iso8601[slot][0];
(void) ngx_sprintf(p3, "%4d-%02d-%02dT%02d:%02d:%02d%c%02d:%02d",
tm.ngx_tm_year, tm.ngx_tm_mon,
tm.ngx_tm_mday, tm.ngx_tm_hour,
tm.ngx_tm_min, tm.ngx_tm_sec,
tp->gmtoff < 0 ? '-' : '+',
ngx_abs(tp->gmtoff / 60), ngx_abs(tp->gmtoff % 60));
ngx_memory_barrier();
ngx_cached_time = tp;
ngx_cached_http_time.data = p0;
ngx_cached_err_log_time.data = p1;
ngx_cached_http_log_time.data = p2;
ngx_cached_http_log_iso8601.data = p3;
ngx_unlock(&ngx_time_lock);
}
void
ngx_close_connection(ngx_connection_t *c)
{
ngx_err_t err;
ngx_uint_t log_error, level;
ngx_socket_t fd;
if (c->fd == -1) {
ngx_log_error(NGX_LOG_ALERT, c->log, 0, "connection already closed");
return;
}
if (c->read->timer_set) {
ngx_del_timer(c->read);
}
if (c->write->timer_set) {
ngx_del_timer(c->write);
}
if (ngx_del_conn) {
ngx_del_conn(c, NGX_CLOSE_EVENT);
} else {
if (c->read->active || c->read->disabled) {
ngx_del_event(c->read, NGX_READ_EVENT, NGX_CLOSE_EVENT);
}
if (c->write->active || c->write->disabled) {
ngx_del_event(c->write, NGX_WRITE_EVENT, NGX_CLOSE_EVENT);
}
}
#if (NGX_THREADS)
/*
* we have to clean the connection information before the closing
* because another thread may reopen the same file descriptor
* before we clean the connection
*/
ngx_mutex_lock(ngx_posted_events_mutex);
if (c->read->prev) {
ngx_delete_posted_event(c->read);
}
if (c->write->prev) {
ngx_delete_posted_event(c->write);
}
c->read->closed = 1;
c->write->closed = 1;
if (c->single_connection) {
ngx_unlock(&c->lock);
c->read->locked = 0;
c->write->locked = 0;
}
ngx_mutex_unlock(ngx_posted_events_mutex);
#else
if (c->read->prev) {
ngx_delete_posted_event(c->read);
}
if (c->write->prev) {
ngx_delete_posted_event(c->write);
}
c->read->closed = 1;
c->write->closed = 1;
#endif
ngx_reusable_connection(c, 0);
log_error = c->log_error;
ngx_free_connection(c);
fd = c->fd;
c->fd = (ngx_socket_t) -1;
if (ngx_close_socket(fd) == -1) {
err = ngx_socket_errno;
if (err == NGX_ECONNRESET || err == NGX_ENOTCONN) {
switch (log_error) {
case NGX_ERROR_INFO:
level = NGX_LOG_INFO;
break;
case NGX_ERROR_ERR:
level = NGX_LOG_ERR;
break;
default:
level = NGX_LOG_CRIT;
}
} else {
level = NGX_LOG_CRIT;
}
/* we use ngx_cycle->log because c->log was in c->pool */
ngx_log_error(level, ngx_cycle->log, err,
ngx_close_socket_n " %d failed", fd);
}
}
static void *
ngx_thread_pool_cycle(void *data)
{
ngx_thread_pool_t *tp = data;
int err;
sigset_t set;
ngx_thread_task_t *task;
#if 0
ngx_time_update();
#endif
ngx_log_debug1(NGX_LOG_DEBUG_CORE, tp->log, 0,
"thread in pool \"%V\" started", &tp->name);
sigfillset(&set);
sigdelset(&set, SIGILL);
sigdelset(&set, SIGFPE);
sigdelset(&set, SIGSEGV);
sigdelset(&set, SIGBUS);
err = pthread_sigmask(SIG_BLOCK, &set, NULL);
if (err)
{
ngx_log_error(NGX_LOG_ALERT, tp->log, err, "pthread_sigmask() failed");
return NULL;
}
for (;;)
{
if (ngx_thread_mutex_lock(&tp->mtx, tp->log) != NGX_OK)
{
return NULL;
}
/* the number may become negative */
tp->waiting--;
while (tp->queue.first == NULL)
{
if (ngx_thread_cond_wait(&tp->cond, &tp->mtx, tp->log)
!= NGX_OK)
{
(void) ngx_thread_mutex_unlock(&tp->mtx, tp->log);
return NULL;
}
}
task = tp->queue.first;
tp->queue.first = task->next;
if (tp->queue.first == NULL)
{
tp->queue.last = &tp->queue.first;
}
if (ngx_thread_mutex_unlock(&tp->mtx, tp->log) != NGX_OK)
{
return NULL;
}
#if 0
ngx_time_update();
#endif
ngx_log_debug2(NGX_LOG_DEBUG_CORE, tp->log, 0,
"run task #%ui in thread pool \"%V\"",
task->id, &tp->name);
task->handler(task->ctx, tp->log);
ngx_log_debug2(NGX_LOG_DEBUG_CORE, tp->log, 0,
"complete task #%ui in thread pool \"%V\"",
task->id, &tp->name);
task->next = NULL;
ngx_spinlock(&ngx_thread_pool_done_lock, 1, 2048);
*ngx_thread_pool_done.last = task;
ngx_thread_pool_done.last = &task->next;
ngx_unlock(&ngx_thread_pool_done_lock);
(void) ngx_notify(ngx_thread_pool_handler);
}
}
//ngx_thread_pool_cycle和ngx_thread_task_post配合阅读
static void *
ngx_thread_pool_cycle(void *data)
{
ngx_thread_pool_t *tp = data; //一个该结构对应一个threads_pool配置
int err;
sigset_t set;
ngx_thread_task_t *task;
#if 0
ngx_time_update();
#endif
ngx_log_debug1(NGX_LOG_DEBUG_CORE, tp->log, 0,
"thread in pool \"%V\" started", &tp->name);
sigfillset(&set);
sigdelset(&set, SIGILL);
sigdelset(&set, SIGFPE);
sigdelset(&set, SIGSEGV);
sigdelset(&set, SIGBUS);
err = pthread_sigmask(SIG_BLOCK, &set, NULL); //
if (err) {
ngx_log_error(NGX_LOG_ALERT, tp->log, err, "pthread_sigmask() failed");
return NULL;
}
/*
一般主线程通过ngx_thread_task_post添加任务，线程队列中的线程执行任务，主线程号和进程号一样，线程队列中的线程和进程号不一样，例如
2016/01/07 12:38:01[ ngx_thread_task_post, 280][yangya [debug] 20090#20090: ngx add task to thread, task id:183
20090#20090前面是进程号，后面是主线程号，他们相同
*/
for ( ;; ) {//一次任务执行完后又会走到这里，循环
if (ngx_thread_mutex_lock(&tp->mtx, tp->log) != NGX_OK) {
return NULL;
}
/* the number may become negative */
tp->waiting--;
//如果队列中有任务，则直接执行任务，不会在while中等待conf signal
while (tp->queue.first == NULL) { //此时任务队列为空，在条件变量上等待 配合ngx_thread_task_post阅读
//在添加任务的时候唤醒ngx_thread_task_post -> ngx_thread_cond_signal
if (ngx_thread_cond_wait(&tp->cond, &tp->mtx, tp->log) //等待ngx_thread_cond_signal后才会返回
!= NGX_OK)
{
(void) ngx_thread_mutex_unlock(&tp->mtx, tp->log);
return NULL;
}
}
//取出队首任务，然后执行
task = tp->queue.first;
tp->queue.first = task->next;
if (tp->queue.first == NULL) {
tp->queue.last = &tp->queue.first;
}
//这一段加锁是因为线程池是共享资源，多个线程都从队列中取线程，并且主线程会添加任务到队列中
if (ngx_thread_mutex_unlock(&tp->mtx, tp->log) != NGX_OK) {
return NULL;
}
#if 0
ngx_time_update();
#endif
ngx_log_debug2(NGX_LOG_DEBUG_CORE, tp->log, 0,
"run task #%ui in thread pool name:\"%V\"",
task->id, &tp->name);
task->handler(task->ctx, tp->log); //每个任务有各自的ctx,因此这里不需要加锁
ngx_log_debug2(NGX_LOG_DEBUG_CORE, tp->log, 0,
"complete task #%ui in thread pool name: \"%V\"",
task->id, &tp->name);
task->next = NULL;
ngx_spinlock(&ngx_thread_pool_done_lock, 1, 2048);
//task添加到队列尾部，同时可以保证多次添加的时候，让新task和以前的task形成一个还，first执行第一个task，last指向最后一个task
*ngx_thread_pool_done.last = task;
ngx_thread_pool_done.last = &task->next;
ngx_unlock(&ngx_thread_pool_done_lock);
//ngx_notify通告主线程，该任务处理完毕，ngx_thread_pool_handler由主线程执行，也就是进程cycle{}通过epoll_wait返回执行，而不是由线程池中的线程执行
(void) ngx_notify(ngx_thread_pool_handler);
}
}
void ngx_close_connection(ngx_connection_t *c)
{
ngx_socket_t fd;
if (c->pool == NULL)
{
ngx_log_error(NGX_LOG_ALERT, c->log, 0, "connection already closed");
return;
}
#if (NGX_OPENSSL)
if (c->ssl)
{
if (ngx_ssl_shutdown(c) == NGX_AGAIN)
{
c->read->event_handler = ngx_ssl_close_handler;
c->write->event_handler = ngx_ssl_close_handler;
return;
}
}
#endif
if (c->read->timer_set)
{
ngx_del_timer(c->read);
}
if (c->write->timer_set)
{
ngx_del_timer(c->write);
}
if (ngx_del_conn)
{
ngx_del_conn(c, NGX_CLOSE_EVENT);
}
else
{
if (c->read->active || c->read->disabled)
{
ngx_del_event(c->read, NGX_READ_EVENT, NGX_CLOSE_EVENT);
}
if (c->write->active || c->write->disabled)
{
ngx_del_event(c->write, NGX_WRITE_EVENT, NGX_CLOSE_EVENT);
}
}
#if (NGX_THREADS)
/*
* we have to clean the connection information before the closing
* because another thread may reopen the same file descriptor
* before we clean the connection
*/
if (ngx_mutex_lock(ngx_posted_events_mutex) == NGX_OK)
{
if (c->read->prev)
{
ngx_delete_posted_event(c->read);
}
if (c->write->prev)
{
ngx_delete_posted_event(c->write);
}
c->read->closed = 1;
c->write->closed = 1;
if (c->single_connection)
{
ngx_unlock(&c->lock);
c->read->locked = 0;
c->write->locked = 0;
}
ngx_mutex_unlock(ngx_posted_events_mutex);
}
#else
if (c->read->prev)
{
ngx_delete_posted_event(c->read);
}
if (c->write->prev)
{
ngx_delete_posted_event(c->write);
}
c->read->closed = 1;
c->write->closed = 1;
#endif
fd = c->fd;
c->fd = (ngx_socket_t) -1;
c->data = NULL;
ngx_destroy_pool(c->pool);
if (ngx_close_socket(fd) == -1)
{
/* we use ngx_cycle->log because c->log was in c->pool */
ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_socket_errno,
ngx_close_socket_n " failed");
}
}
