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ngx_process_cycle.c
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// annotated by chrono since 2016
/*
* Copyright (C) Igor Sysoev
* Copyright (C) Nginx, Inc.
*/
#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_event.h>
#include <ngx_channel.h>
// 被ngx_master_process_cycle()调用
// 启动worker进程，数量由配置决定，即worker_processes指令
// 调用时传递的是#define NGX_PROCESS_RESPAWN -3
static void ngx_start_worker_processes(ngx_cycle_t *cycle, ngx_int_t n,
ngx_int_t type);
// cache相关的暂不研究
static void ngx_start_cache_manager_processes(ngx_cycle_t *cycle,
ngx_uint_t respawn);
static void ngx_pass_open_channel(ngx_cycle_t *cycle, ngx_channel_t *ch);
// master进程调用，遍历ngx_processes数组，用kill发送信号
static void ngx_signal_worker_processes(ngx_cycle_t *cycle, int signo);
static ngx_uint_t ngx_reap_children(ngx_cycle_t *cycle);
// 删除pid，模块清理，关闭监听端口
static void ngx_master_process_exit(ngx_cycle_t *cycle);
// 传递给ngx_spawn_process()，是worker进程的核心功能
// 调用ngx_worker_process_init()/ngx_worker_process_exit()
static void ngx_worker_process_cycle(ngx_cycle_t *cycle, void *data);
// 读取核心配置，设置cpu优先级,core dump信息,unix运行的group/user
// 切换工作路径,根据pid设置随机数种子
// 调用所有模块的init_process,让模块进程初始化
static void ngx_worker_process_init(ngx_cycle_t *cycle, ngx_int_t worker);
// 被ngx_worker_process_cycle()调用
// 调用所有模块的exit_process，进程结束hook
// 内部直接exit(0)退出
static void ngx_worker_process_exit(ngx_cycle_t *cycle);
// cache相关的暂不研究
static void ngx_channel_handler(ngx_event_t *ev);
static void ngx_cache_manager_process_cycle(ngx_cycle_t *cycle, void *data);
static void ngx_cache_manager_process_handler(ngx_event_t *ev);
static void ngx_cache_loader_process_handler(ngx_event_t *ev);
// 标记nginx进程的状态
// NGX_PROCESS_MASTER/NGX_PROCESS_WORKER/NGX_PROCESS_SINGLE
// 一开始是0，也就是NGX_PROCESS_SINGLE
ngx_uint_t ngx_process;
// 记录nginx master进程的pid，在main()里使用
ngx_pid_t ngx_pid;
// 原子变量，用于进程中检查信号
sig_atomic_t ngx_reap;
sig_atomic_t ngx_sigio;
sig_atomic_t ngx_sigalrm; //更新时间的信号
sig_atomic_t ngx_terminate; //结束进程
sig_atomic_t ngx_quit; //处理完所有请求再结束进程
sig_atomic_t ngx_debug_quit;
ngx_uint_t ngx_exiting; //nginx进程正在退出过程中
sig_atomic_t ngx_reconfigure; //重新加载配置文件，也就是reload
sig_atomic_t ngx_reopen; //重新打开所有文件
sig_atomic_t ngx_change_binary;
ngx_pid_t ngx_new_binary;
ngx_uint_t ngx_inherited;
ngx_uint_t ngx_daemonized;
sig_atomic_t ngx_noaccept;
ngx_uint_t ngx_noaccepting;
ngx_uint_t ngx_restart;
// master进程的名字
static u_char master_process[] = "master process";
static ngx_cache_manager_ctx_t ngx_cache_manager_ctx = {
ngx_cache_manager_process_handler, "cache manager process", 0
};
static ngx_cache_manager_ctx_t ngx_cache_loader_ctx = {
ngx_cache_loader_process_handler, "cache loader process", 60000
};
static ngx_cycle_t ngx_exit_cycle;
static ngx_log_t ngx_exit_log;
static ngx_open_file_t ngx_exit_log_file;
// main()函数里调用，启动worker进程
// 监听信号
// 核心操作是sigsuspend，暂时挂起进程，不占用CPU，只有收到信号时才被唤醒
void
ngx_master_process_cycle(ngx_cycle_t *cycle)
{
char *title;
u_char *p;
size_t size;
ngx_int_t i;
ngx_uint_t n, sigio;
sigset_t set;
struct itimerval itv;
ngx_uint_t live;
ngx_msec_t delay;
ngx_listening_t *ls;
ngx_core_conf_t *ccf;
// 屏蔽一些信号,master进程不关注
sigemptyset(&set);
sigaddset(&set, SIGCHLD);
sigaddset(&set, SIGALRM);
sigaddset(&set, SIGIO);
sigaddset(&set, SIGINT);
sigaddset(&set, ngx_signal_value(NGX_RECONFIGURE_SIGNAL));
sigaddset(&set, ngx_signal_value(NGX_REOPEN_SIGNAL));
sigaddset(&set, ngx_signal_value(NGX_NOACCEPT_SIGNAL));
sigaddset(&set, ngx_signal_value(NGX_TERMINATE_SIGNAL));
sigaddset(&set, ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
sigaddset(&set, ngx_signal_value(NGX_CHANGEBIN_SIGNAL));
if (sigprocmask(SIG_BLOCK, &set, NULL) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"sigprocmask() failed");
}
sigemptyset(&set);
// static u_char master_process[] = "master process";
// 计算master进程的名字
size = sizeof(master_process);
// 加上命令行参数，注意使用的是nginx拷贝后的参数
for (i = 0; i < ngx_argc; i++) {
size += ngx_strlen(ngx_argv[i]) + 1;
}
// 分配名字的内存
title = ngx_pnalloc(cycle->pool, size);
if (title == NULL) {
/* fatal */
exit(2);
}
// 拷贝字符串
p = ngx_cpymem(title, master_process, sizeof(master_process) - 1);
for (i = 0; i < ngx_argc; i++) {
*p++ = ' ';
p = ngx_cpystrn(p, (u_char *) ngx_argv[i], size);
}
// 设置进程名
ngx_setproctitle(title);
// 取core模块配置
ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module);
// 启动worker进程，数量由配置决定，即worker_processes指令
// #define NGX_PROCESS_RESPAWN -3
ngx_start_worker_processes(cycle, ccf->worker_processes,
NGX_PROCESS_RESPAWN);
// cache进程
ngx_start_cache_manager_processes(cycle, 0);
ngx_new_binary = 0;
delay = 0; //延时的计数器
sigio = 0;
live = 1; //是否有存活的子进程
// master进程的无限循环，只处理信号
// 主要调用ngx_signal_worker_processes()发送信号
// ngx_start_worker_processes()产生新子进程
for ( ;; ) {
if (delay) {
if (ngx_sigalrm) {
sigio = 0;
delay *= 2; //延时加倍
ngx_sigalrm = 0;
}
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
"termination cycle: %d", delay);
itv.it_interval.tv_sec = 0;
itv.it_interval.tv_usec = 0;
itv.it_value.tv_sec = delay / 1000;
itv.it_value.tv_usec = (delay % 1000 ) * 1000;
// 系统调用，设置发送SIGALRM的时间间隔
if (setitimer(ITIMER_REAL, &itv, NULL) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"setitimer() failed");
}
}
ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "sigsuspend");
// 核心操作是sigsuspend，暂时挂起进程，不占用CPU，只有收到信号时才被唤醒
// 收到SIGALRM就检查子进程是否都已经处理完了
sigsuspend(&set);
// 更新一下时间
ngx_time_update();
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
"wake up, sigio %i", sigio);
if (ngx_reap) {
ngx_reap = 0;
ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "reap children");
live = ngx_reap_children(cycle);
}
// 无存活子进程且收到stop/quit信号
if (!live && (ngx_terminate || ngx_quit)) {
// 删除pid，模块清理，关闭监听端口
// 内部直接exit(0)退出
ngx_master_process_exit(cycle);
}
// 收到了-s stop，停止进程
if (ngx_terminate) {
// 延时等待子进程关闭
if (delay == 0) {
delay = 50;
}
if (sigio) {
sigio--;
continue;
}
sigio = ccf->worker_processes + 2 /* cache processes */;
if (delay > 1000) {
// 超时太多，直接发送SIGKILL杀死进程
// master进程调用，遍历ngx_processes数组，用kill发送信号
ngx_signal_worker_processes(cycle, SIGKILL);
} else {
// master进程调用，遍历ngx_processes数组，用kill发送信号
// 走到worker进程的ngx_signal_handler()
// 然后再是ngx_worker_process_cycle()的ngx_terminate
ngx_signal_worker_processes(cycle,
ngx_signal_value(NGX_TERMINATE_SIGNAL));
}
// 等待SIGALRM信号，检查子进程是否都结束
continue;
}
// 收到了-s quit，关闭监听端口后再停止进程（优雅关闭）
if (ngx_quit) {
// master进程调用，遍历ngx_processes数组，用kill发送信号
// 走到worker进程的ngx_signal_handler()
// 然后再是ngx_worker_process_cycle()的ngx_quit
ngx_signal_worker_processes(cycle,
ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
ls = cycle->listening.elts;
for (n = 0; n < cycle->listening.nelts; n++) {
if (ngx_close_socket(ls[n].fd) == -1) {
ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_socket_errno,
ngx_close_socket_n " %V failed",
&ls[n].addr_text);
}
}
cycle->listening.nelts = 0;
continue;
}
// 收到了-s reload重新配置
if (ngx_reconfigure) {
ngx_reconfigure = 0;
// 启动新的nginx二进制
if (ngx_new_binary) {
// 启动worker进程，数量由配置决定，即worker_processes指令
// 调用时传递的是#define NGX_PROCESS_RESPAWN -3
ngx_start_worker_processes(cycle, ccf->worker_processes,
NGX_PROCESS_RESPAWN);
ngx_start_cache_manager_processes(cycle, 0);
ngx_noaccepting = 0;
continue;
}
ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "reconfiguring");
// nginx可执行程序不变，以当前cycle重新初始化
cycle = ngx_init_cycle(cycle);
if (cycle == NULL) {
cycle = (ngx_cycle_t *) ngx_cycle;
continue;
}
ngx_cycle = cycle;
ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx,
ngx_core_module);
// 启动worker进程，数量由配置决定，即worker_processes指令
// 调用时传递的是#define NGX_PROCESS_JUST_RESPAWN -2
// 这样新启动的进程不会发送shutdown信号
ngx_start_worker_processes(cycle, ccf->worker_processes,
NGX_PROCESS_JUST_RESPAWN);
ngx_start_cache_manager_processes(cycle, 1);
/* allow new processes to start */
// 阻塞等待100毫秒
ngx_msleep(100);
// 设置进程存活标志
live = 1;
// 关闭原来的worker进程
// 新启动的进程不会发送shutdown信号
// master进程调用，遍历ngx_processes数组，用kill发送信号
// 走到worker进程的ngx_signal_handler()
// 然后再是ngx_worker_process_cycle()的ngx_quit
ngx_signal_worker_processes(cycle,
ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
}
if (ngx_restart) {
ngx_restart = 0;
// 启动worker进程，数量由配置决定，即worker_processes指令
// 调用时传递的是#define NGX_PROCESS_RESPAWN -3
ngx_start_worker_processes(cycle, ccf->worker_processes,
NGX_PROCESS_RESPAWN);
ngx_start_cache_manager_processes(cycle, 0);
// 设置进程存活标志
live = 1;
}
if (ngx_reopen) {
ngx_reopen = 0;
ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "reopening logs");
ngx_reopen_files(cycle, ccf->user);
ngx_signal_worker_processes(cycle,
ngx_signal_value(NGX_REOPEN_SIGNAL));
}
if (ngx_change_binary) {
ngx_change_binary = 0;
ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "changing binary");
ngx_new_binary = ngx_exec_new_binary(cycle, ngx_argv);
}
if (ngx_noaccept) {
ngx_noaccept = 0;
ngx_noaccepting = 1;
ngx_signal_worker_processes(cycle,
ngx_signal_value(NGX_SHUTDOWN_SIGNAL));
}
} //master进程无限循环结束
}
// main()函数里调用，仅启动一个进程
// master_process off;
void
ngx_single_process_cycle(ngx_cycle_t *cycle)
{
ngx_uint_t i;
if (ngx_set_environment(cycle, NULL) == NULL) {
/* fatal */
exit(2);
}
// 调用所有模块的init_process，即进程启动时hook
for (i = 0; ngx_modules[i]; i++) {
if (ngx_modules[i]->init_process) {
if (ngx_modules[i]->init_process(cycle) == NGX_ERROR) {
/* fatal */
exit(2);
}
}
}
// 无限循环，对外提供服务
// ngx_signal_handler处理unix信号
// 收到信号后设置ngx_quit/ngx_sigalrm/ngx_reconfigue等全局变量
// 由无限循环检查这些变量再处理
for ( ;; ) {
ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "worker cycle");
// 处理事件的核心函数, event模块里
ngx_process_events_and_timers(cycle);
// 检查是否处于退出状态
if (ngx_terminate || ngx_quit) {
// 所有模块的退出hook
for (i = 0; ngx_modules[i]; i++) {
if (ngx_modules[i]->exit_process) {
ngx_modules[i]->exit_process(cycle);
}
}
// 删除pid，模块清理，关闭监听端口
// 内部直接exit(0)退出
ngx_master_process_exit(cycle);
}
// 重新配置，以当前cycle重新初始化，即reload
if (ngx_reconfigure) {
ngx_reconfigure = 0; //标志量清零
ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "reconfiguring");
// 以当前cycle重新初始化
cycle = ngx_init_cycle(cycle);
if (cycle == NULL) {
cycle = (ngx_cycle_t *) ngx_cycle;
continue;
}
ngx_cycle = cycle;
}
// 重新打开所有文件
if (ngx_reopen) {
ngx_reopen = 0;
ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "reopening logs");
ngx_reopen_files(cycle, (ngx_uid_t) -1);
}
}
}
// 被ngx_master_process_cycle()调用
// 启动worker进程，数量由配置决定，即worker_processes指令
// 调用时传递的是#define NGX_PROCESS_RESPAWN -3
static void
ngx_start_worker_processes(ngx_cycle_t *cycle, ngx_int_t n, ngx_int_t type)
{
ngx_int_t i;
ngx_channel_t ch;
ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "start worker processes");
ngx_memzero(&ch, sizeof(ngx_channel_t));
// unix channel
ch.command = NGX_CMD_OPEN_CHANNEL;
for (i = 0; i < n; i++) {
// os/unix/ngx_process.c产生进程，执行ngx_worker_process_cycle
// 创建的进程都在ngx_processes数组里
// 定义在os/unix/ngx_process.c
// ngx_process_t ngx_processes[NGX_MAX_PROCESSES];
ngx_spawn_process(cycle, ngx_worker_process_cycle,
(void *) (intptr_t) i, "worker process", type);
// 设置channel信息
ch.pid = ngx_processes[ngx_process_slot].pid;
ch.slot = ngx_process_slot;
ch.fd = ngx_processes[ngx_process_slot].channel[0];
// 建立channel，用于进程间通信
ngx_pass_open_channel(cycle, &ch);
}
}
static void
ngx_start_cache_manager_processes(ngx_cycle_t *cycle, ngx_uint_t respawn)
{
ngx_uint_t i, manager, loader;
ngx_path_t **path;
ngx_channel_t ch;
manager = 0;
loader = 0;
path = ngx_cycle->paths.elts;
for (i = 0; i < ngx_cycle->paths.nelts; i++) {
if (path[i]->manager) {
manager = 1;
}
if (path[i]->loader) {
loader = 1;
}
}
if (manager == 0) {
return;
}
ngx_spawn_process(cycle, ngx_cache_manager_process_cycle,
&ngx_cache_manager_ctx, "cache manager process",
respawn ? NGX_PROCESS_JUST_RESPAWN : NGX_PROCESS_RESPAWN);
ngx_memzero(&ch, sizeof(ngx_channel_t));
ch.command = NGX_CMD_OPEN_CHANNEL;
ch.pid = ngx_processes[ngx_process_slot].pid;
ch.slot = ngx_process_slot;
ch.fd = ngx_processes[ngx_process_slot].channel[0];
ngx_pass_open_channel(cycle, &ch);
if (loader == 0) {
return;
}
ngx_spawn_process(cycle, ngx_cache_manager_process_cycle,
&ngx_cache_loader_ctx, "cache loader process",
respawn ? NGX_PROCESS_JUST_SPAWN : NGX_PROCESS_NORESPAWN);
ch.command = NGX_CMD_OPEN_CHANNEL;
ch.pid = ngx_processes[ngx_process_slot].pid;
ch.slot = ngx_process_slot;
ch.fd = ngx_processes[ngx_process_slot].channel[0];
ngx_pass_open_channel(cycle, &ch);
}
static void
ngx_pass_open_channel(ngx_cycle_t *cycle, ngx_channel_t *ch)
{
ngx_int_t i;
for (i = 0; i < ngx_last_process; i++) {
if (i == ngx_process_slot
|| ngx_processes[i].pid == -1
|| ngx_processes[i].channel[0] == -1)
{
continue;
}
ngx_log_debug6(NGX_LOG_DEBUG_CORE, cycle->log, 0,
"pass channel s:%d pid:%P fd:%d to s:%i pid:%P fd:%d",
ch->slot, ch->pid, ch->fd,
i, ngx_processes[i].pid,
ngx_processes[i].channel[0]);
/* TODO: NGX_AGAIN */
ngx_write_channel(ngx_processes[i].channel[0],
ch, sizeof(ngx_channel_t), cycle->log);
}
}
// master进程调用，遍历ngx_processes数组，用kill发送信号
static void
ngx_signal_worker_processes(ngx_cycle_t *cycle, int signo)
{
ngx_int_t i;
ngx_err_t err;
ngx_channel_t ch;
ngx_memzero(&ch, sizeof(ngx_channel_t));
#if (NGX_BROKEN_SCM_RIGHTS)
ch.command = 0;
#else
switch (signo) {
case ngx_signal_value(NGX_SHUTDOWN_SIGNAL):
ch.command = NGX_CMD_QUIT;
break;
case ngx_signal_value(NGX_TERMINATE_SIGNAL):
ch.command = NGX_CMD_TERMINATE;
break;
case ngx_signal_value(NGX_REOPEN_SIGNAL):
ch.command = NGX_CMD_REOPEN;
break;
default:
ch.command = 0;
}
#endif
ch.fd = -1;
// 遍历ngx_processes数组，用kill发送信号
for (i = 0; i < ngx_last_process; i++) {
ngx_log_debug7(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
"child: %d %P e:%d t:%d d:%d r:%d j:%d",
i,
ngx_processes[i].pid,
ngx_processes[i].exiting,
ngx_processes[i].exited,
ngx_processes[i].detached,
ngx_processes[i].respawn,
ngx_processes[i].just_spawn);
if (ngx_processes[i].detached || ngx_processes[i].pid == -1) {
continue;
}
// 新启动的进程不会发送信号
if (ngx_processes[i].just_spawn) {
ngx_processes[i].just_spawn = 0;
continue;
}
if (ngx_processes[i].exiting
&& signo == ngx_signal_value(NGX_SHUTDOWN_SIGNAL))
{
continue;
}
if (ch.command) {
if (ngx_write_channel(ngx_processes[i].channel[0],
&ch, sizeof(ngx_channel_t), cycle->log)
== NGX_OK)
{
if (signo != ngx_signal_value(NGX_REOPEN_SIGNAL)) {
ngx_processes[i].exiting = 1;
}
continue;
}
}
ngx_log_debug2(NGX_LOG_DEBUG_CORE, cycle->log, 0,
"kill (%P, %d)", ngx_processes[i].pid, signo);
// kill发送信号
if (kill(ngx_processes[i].pid, signo) == -1) {
err = ngx_errno;
ngx_log_error(NGX_LOG_ALERT, cycle->log, err,
"kill(%P, %d) failed", ngx_processes[i].pid, signo);
if (err == NGX_ESRCH) {
ngx_processes[i].exited = 1;
ngx_processes[i].exiting = 0;
ngx_reap = 1;
}
continue;
}
if (signo != ngx_signal_value(NGX_REOPEN_SIGNAL)) {
ngx_processes[i].exiting = 1;
}
}
}
static ngx_uint_t
ngx_reap_children(ngx_cycle_t *cycle)
{
ngx_int_t i, n;
ngx_uint_t live;
ngx_channel_t ch;
ngx_core_conf_t *ccf;
ngx_memzero(&ch, sizeof(ngx_channel_t));
ch.command = NGX_CMD_CLOSE_CHANNEL;
ch.fd = -1;
live = 0;
for (i = 0; i < ngx_last_process; i++) {
ngx_log_debug7(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
"child: %d %P e:%d t:%d d:%d r:%d j:%d",
i,
ngx_processes[i].pid,
ngx_processes[i].exiting,
ngx_processes[i].exited,
ngx_processes[i].detached,
ngx_processes[i].respawn,
ngx_processes[i].just_spawn);
if (ngx_processes[i].pid == -1) {
continue;
}
if (ngx_processes[i].exited) {
if (!ngx_processes[i].detached) {
ngx_close_channel(ngx_processes[i].channel, cycle->log);
ngx_processes[i].channel[0] = -1;
ngx_processes[i].channel[1] = -1;
ch.pid = ngx_processes[i].pid;
ch.slot = i;
for (n = 0; n < ngx_last_process; n++) {
if (ngx_processes[n].exited
|| ngx_processes[n].pid == -1
|| ngx_processes[n].channel[0] == -1)
{
continue;
}
ngx_log_debug3(NGX_LOG_DEBUG_CORE, cycle->log, 0,
"pass close channel s:%i pid:%P to:%P",
ch.slot, ch.pid, ngx_processes[n].pid);
/* TODO: NGX_AGAIN */
ngx_write_channel(ngx_processes[n].channel[0],
&ch, sizeof(ngx_channel_t), cycle->log);
}
}
if (ngx_processes[i].respawn
&& !ngx_processes[i].exiting
&& !ngx_terminate
&& !ngx_quit)
{
if (ngx_spawn_process(cycle, ngx_processes[i].proc,
ngx_processes[i].data,
ngx_processes[i].name, i)
== NGX_INVALID_PID)
{
ngx_log_error(NGX_LOG_ALERT, cycle->log, 0,
"could not respawn %s",
ngx_processes[i].name);
continue;
}
ch.command = NGX_CMD_OPEN_CHANNEL;
ch.pid = ngx_processes[ngx_process_slot].pid;
ch.slot = ngx_process_slot;
ch.fd = ngx_processes[ngx_process_slot].channel[0];
ngx_pass_open_channel(cycle, &ch);
live = 1;
continue;
}
if (ngx_processes[i].pid == ngx_new_binary) {
ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx,
ngx_core_module);
if (ngx_rename_file((char *) ccf->oldpid.data,
(char *) ccf->pid.data)
== NGX_FILE_ERROR)
{
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
ngx_rename_file_n " %s back to %s failed "
"after the new binary process \"%s\" exited",
ccf->oldpid.data, ccf->pid.data, ngx_argv[0]);
}
ngx_new_binary = 0;
if (ngx_noaccepting) {
ngx_restart = 1;
ngx_noaccepting = 0;
}
}
if (i == ngx_last_process - 1) {
ngx_last_process--;
} else {
ngx_processes[i].pid = -1;
}
} else if (ngx_processes[i].exiting || !ngx_processes[i].detached) {
live = 1;
}
}
return live;
}
// 删除pid，模块清理，关闭监听端口
// 内部直接exit(0)退出
static void
ngx_master_process_exit(ngx_cycle_t *cycle)
{
ngx_uint_t i;
ngx_delete_pidfile(cycle);
ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "exit");
for (i = 0; ngx_modules[i]; i++) {
if (ngx_modules[i]->exit_master) {
ngx_modules[i]->exit_master(cycle);
}
}
// in ngx_connection.c
// 遍历监听端口列表，逐个删除监听事件
ngx_close_listening_sockets(cycle);
/*
* Copy ngx_cycle->log related data to the special static exit cycle,
* log, and log file structures enough to allow a signal handler to log.
* The handler may be called when standard ngx_cycle->log allocated from
* ngx_cycle->pool is already destroyed.
*/
ngx_exit_log = *ngx_log_get_file_log(ngx_cycle->log);
ngx_exit_log_file.fd = ngx_exit_log.file->fd;
ngx_exit_log.file = &ngx_exit_log_file;
ngx_exit_log.next = NULL;
ngx_exit_log.writer = NULL;
ngx_exit_cycle.log = &ngx_exit_log;
ngx_exit_cycle.files = ngx_cycle->files;
ngx_exit_cycle.files_n = ngx_cycle->files_n;
ngx_cycle = &ngx_exit_cycle;
ngx_destroy_pool(cycle->pool);
exit(0);
}
// 传递给ngx_spawn_process()，是worker进程的核心功能
// data实际上是进程号, (void *) (intptr_t) i
static void
ngx_worker_process_cycle(ngx_cycle_t *cycle, void *data)
{
// 把data再转换为进程序号
ngx_int_t worker = (intptr_t) data;
ngx_uint_t i;
ngx_connection_t *c;
// 设置进程状态
ngx_process = NGX_PROCESS_WORKER;
// 读取核心配置，设置cpu优先级,core dump信息,unix运行的group/user
// 切换工作路径,根据pid设置随机数种子
// 调用所有模块的init_process,让模块进程初始化
ngx_worker_process_init(cycle, worker);
// 设置进程名字
ngx_setproctitle("worker process");
// 无限循环，处理事件和信号
for ( ;; ) {
// 进程正在退出,即quit
if (ngx_exiting) {
c = cycle->connections;
for (i = 0; i < cycle->connection_n; i++) {
/* THREAD: lock */
if (c[i].fd != -1 && c[i].idle) {
c[i].close = 1;
c[i].read->handler(c[i].read);
}
}
ngx_event_cancel_timers();
if (ngx_event_timer_rbtree.root == ngx_event_timer_rbtree.sentinel)
{
ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "exiting");
// 调用所有模块的exit_process，进程结束hook
// 内部直接exit(0)退出
ngx_worker_process_exit(cycle);
}
}
ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "worker cycle");
// 处理事件的核心函数, event模块里
ngx_process_events_and_timers(cycle);
// 收到了-s stop，停止进程
if (ngx_terminate) {
ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "exiting");
// 调用所有模块的exit_process，进程结束hook
// 内部直接exit(0)退出
ngx_worker_process_exit(cycle);
}
// 收到了-s quit，关闭监听端口后再停止进程（优雅关闭）
if (ngx_quit) {
ngx_quit = 0;
ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0,
"gracefully shutting down");
// 改进程名字
ngx_setproctitle("worker process is shutting down");
if (!ngx_exiting) {
// in ngx_connection.c
// 遍历监听端口列表，逐个删除监听事件
ngx_close_listening_sockets(cycle);
// 设置ngx_exiting标志，继续走循环
ngx_exiting = 1;
}
}
// 收到了-s reopen，重新打开文件
if (ngx_reopen) {
ngx_reopen = 0;
ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "reopening logs");
ngx_reopen_files(cycle, -1);
}
}
}
// 被ngx_worker_process_cycle()调用
// 参数worker是进程的序号
// 设置cpu优先级,core dump信息,unix运行的group/user
// 切换工作路径,根据pid设置随机数种子
// 调用所有模块的init_process,让模块进程初始化
static void
ngx_worker_process_init(ngx_cycle_t *cycle, ngx_int_t worker)
{
sigset_t set;
uint64_t cpu_affinity;
ngx_int_t n;
ngx_uint_t i;
struct rlimit rlmt;
ngx_core_conf_t *ccf;
ngx_listening_t *ls;
if (ngx_set_environment(cycle, NULL) == NULL) {
/* fatal */
exit(2);
}
// 获取核心配置
ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module);
// 设置cpu优先级
if (worker >= 0 && ccf->priority != 0) {
if (setpriority(PRIO_PROCESS, 0, ccf->priority) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"setpriority(%d) failed", ccf->priority);
}
}
// 设置core dump信息
if (ccf->rlimit_nofile != NGX_CONF_UNSET) {
rlmt.rlim_cur = (rlim_t) ccf->rlimit_nofile;
rlmt.rlim_max = (rlim_t) ccf->rlimit_nofile;
if (setrlimit(RLIMIT_NOFILE, &rlmt) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"setrlimit(RLIMIT_NOFILE, %i) failed",
ccf->rlimit_nofile);
}
}
if (ccf->rlimit_core != NGX_CONF_UNSET) {
rlmt.rlim_cur = (rlim_t) ccf->rlimit_core;
rlmt.rlim_max = (rlim_t) ccf->rlimit_core;
if (setrlimit(RLIMIT_CORE, &rlmt) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"setrlimit(RLIMIT_CORE, %O) failed",
ccf->rlimit_core);
}
}
#ifdef RLIMIT_SIGPENDING
if (ccf->rlimit_sigpending != NGX_CONF_UNSET) {
rlmt.rlim_cur = (rlim_t) ccf->rlimit_sigpending;