/*启动工作进程：两个任务，1是设置父子进程通信，2是根据配置循环创建所有的工作进程*/
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");
//传递给其他子进程的命令，打开channel
ch.command = NGX_CMD_OPEN_CHANNEL;
//创建n个worker进程
for (i = 0; i < n; i++) {
cpu_affinity = ngx_get_cpu_affinity(i);
//[p]fork新进程的具体工作，ngx_worker_process_cycle函数是工作进程要执行的具体工作
ngx_spawn_process(cycle, ngx_worker_process_cycle, NULL,
"worker process", type);
//全局数组,定义在src/os/unix/ngx_process.c文件中，存储元素类型是ngx_process_t。
//注意，ngx_process_slot在spawn函数中已经赋值完毕，就是当前子进程的位置
ch.pid = ngx_processes[ngx_process_slot].pid;
ch.slot = ngx_process_slot;
ch.fd = ngx_processes[ngx_process_slot].channel[0];
//建立通道,用于进程通信
ngx_pass_open_channel(cycle, &ch);
}
}
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");
ch.command = NGX_CMD_OPEN_CHANNEL;
for (i = 0; i < n; i++) {
cpu_affinity = ngx_get_cpu_affinity(i);
ngx_spawn_process(cycle, ngx_worker_process_cycle, NULL,
"worker process", type);
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_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);
}
ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module);
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);
}
}
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;
rlmt.rlim_max = (rlim_t) ccf->rlimit_sigpending;
if (setrlimit(RLIMIT_SIGPENDING, &rlmt) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"setrlimit(RLIMIT_SIGPENDING, %i) failed",
ccf->rlimit_sigpending);
}
}
#endif
if (geteuid() == 0) {
if (setgid(ccf->group) == -1) {
ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_errno,
"setgid(%d) failed", ccf->group);
/* fatal */
exit(2);
}
if (initgroups(ccf->username, ccf->group) == -1) {
ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_errno,
"initgroups(%s, %d) failed",
ccf->username, ccf->group);
}
if (setuid(ccf->user) == -1) {
ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_errno,
"setuid(%d) failed", ccf->user);
/* fatal */
exit(2);
}
}
if (worker >= 0) {
cpu_affinity = ngx_get_cpu_affinity(worker);
if (cpu_affinity) {
ngx_setaffinity(cpu_affinity, cycle->log);
}
}
#if (NGX_HAVE_PR_SET_DUMPABLE)
/* allow coredump after setuid() in Linux 2.4.x */
if (prctl(PR_SET_DUMPABLE, 1, 0, 0, 0) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"prctl(PR_SET_DUMPABLE) failed");
}
#endif
if (ccf->working_directory.len) {
if (chdir((char *) ccf->working_directory.data) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"chdir(\"%s\") failed", ccf->working_directory.data);
/* fatal */
exit(2);
}
}
sigemptyset(&set);
if (sigprocmask(SIG_SETMASK, &set, NULL) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"sigprocmask() failed");
}
srandom((ngx_pid << 16) ^ ngx_time());
/*
* disable deleting previous events for the listening sockets because
* in the worker processes there are no events at all at this point
*/
ls = cycle->listening.elts;
for (i = 0; i < cycle->listening.nelts; i++) {
ls[i].previous = NULL;
}
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);
}
}
}
for (n = 0; n < ngx_last_process; n++) {
if (ngx_processes[n].pid == -1) {
continue;
}
if (n == ngx_process_slot) {
continue;
}
if (ngx_processes[n].channel[1] == -1) {
continue;
}
if (close(ngx_processes[n].channel[1]) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"close() channel failed");
}
}
if (close(ngx_processes[ngx_process_slot].channel[0]) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"close() channel failed");
}
#if 0
ngx_last_process = 0;
#endif
if (ngx_add_channel_event(cycle, ngx_channel, NGX_READ_EVENT,
ngx_channel_handler)
== NGX_ERROR)
{
/* fatal */
exit(2);
}
}
static void
ngx_worker_process_init(ngx_cycle_t *cycle, ngx_int_t worker)
{
sigset_t set;
ngx_int_t n;
ngx_uint_t i;
ngx_cpuset_t *cpu_affinity;
struct rlimit rlmt;
ngx_core_conf_t *ccf;
ngx_listening_t *ls;
if (ngx_set_environment(cycle, NULL) == NULL) {
/* fatal */
exit(2);
}
ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module);
if (worker >= 0 && ccf->priority != 0) {
/*设置工作进程优先级*/
if (setpriority(PRIO_PROCESS, 0, ccf->priority) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"setpriority(%d) failed", ccf->priority);
}
}
if (ccf->rlimit_nofile != NGX_CONF_UNSET) {
rlmt.rlim_cur = (rlim_t) ccf->rlimit_nofile;
rlmt.rlim_max = (rlim_t) ccf->rlimit_nofile;
/*设置工作进程可打开的文件描述符的最大数*/
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;
/*设置工作进程可生成的core文件的最大大小*/
if (setrlimit(RLIMIT_CORE, &rlmt) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"setrlimit(RLIMIT_CORE, %O) failed",
ccf->rlimit_core);
}
}
if (geteuid() == 0) {
/*设置组ID*/
if (setgid(ccf->group) == -1) {
ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_errno,
"setgid(%d) failed", ccf->group);
/* fatal */
exit(2);
}
/*初始化组清单*/
if (initgroups(ccf->username, ccf->group) == -1) {
ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_errno,
"initgroups(%s, %d) failed",
ccf->username, ccf->group);
}
/*设置用户ID*/
if (setuid(ccf->user) == -1) {
ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_errno,
"setuid(%d) failed", ccf->user);
/* fatal */
exit(2);
}
}
if (worker >= 0) {
/*获取配置文件中的worker_cpu_affinit指令的配置*/
cpu_affinity = ngx_get_cpu_affinity(worker);
if (cpu_affinity) {
/*解析并使配置生效，为工作进程分配CPU的工作内核*/
ngx_setaffinity(cpu_affinity, cycle->log);
}
}
#if (NGX_HAVE_PR_SET_DUMPABLE)
/* allow coredump after setuid() in Linux 2.4.x */
if (prctl(PR_SET_DUMPABLE, 1, 0, 0, 0) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"prctl(PR_SET_DUMPABLE) failed");
}
#endif
if (ccf->working_directory.len) {
/*设置进程的工作目录，工作进程在执行过程中会在当前目录下写入运行数据，因此需要对工作目录有相应的权限*/
if (chdir((char *) ccf->working_directory.data) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"chdir(\"%s\") failed", ccf->working_directory.data);
/* fatal */
exit(2);
}
}
/*取消对所有信号的屏蔽*/
sigemptyset(&set);
if (sigprocmask(SIG_SETMASK, &set, NULL) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"sigprocmask() failed");
}
srandom((ngx_pid << 16) ^ ngx_time());
/*
* disable deleting previous events for the listening sockets because
* in the worker processes there are no events at all at this point
*/
/*遍历并设置所有监听套接字的状态*/
ls = cycle->listening.elts;
for (i = 0; i < cycle->listening.nelts; i++) {
ls[i].previous = NULL;
}
for (i = 0; cycle->modules[i]; i++) {
if (cycle->modules[i]->init_process) {
/*初始化Nginx各个模块*/
if (cycle->modules[i]->init_process(cycle) == NGX_ERROR) {
/* fatal */
exit(2);
}
}
}
/*遍历所有其他的工作进程，调用close()将它们用于监听的channel[1]关闭*/
for (n = 0; n < ngx_last_process; n++) {
if (ngx_processes[n].pid == -1) {
continue;
}
/*判断是否为当前的工作进程*/
if (n == ngx_process_slot) {
continue;
}
/*判断进程间通信管道是否正常*/
if (ngx_processes[n].channel[1] == -1) {
continue;
}
/*关闭其他进程的channel[1]*/
if (close(ngx_processes[n].channel[1]) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"close() channel failed");
}
}
/*然后将当前工作进程用于发送消息的channel[0]关闭，只留下channel[1]监听事件的到来*/
if (close(ngx_processes[ngx_process_slot].channel[0]) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"close() channel failed");
}
#if 0
ngx_last_process = 0;
#endif
/*添加管道读取事件，回调函数ngx_channel_handler中，无限循环从管道中读取数据，根据数据内容设置一些全局变量开关*/
/*添加事件使用ngx_event_actions.add*/
if (ngx_add_channel_event(cycle, ngx_channel, NGX_READ_EVENT,
ngx_channel_handler)
== NGX_ERROR)
{
/* fatal */
exit(2);
}
}
// worker进程，cachemanager进程和cacheloader进程的初始化函数
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);
}
ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module);
// 设置worker进程的nice值，cachemanager cacheloader进程不会设置
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);
}
}
// 设置进程最多可以打开的fd数量
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);
}
}
// 设置这个进程独立于系统的coredump属性
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;
rlmt.rlim_max = (rlim_t) ccf->rlimit_sigpending;
if (setrlimit(RLIMIT_SIGPENDING, &rlmt) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"setrlimit(RLIMIT_SIGPENDING, %i) failed",
ccf->rlimit_sigpending);
}
}
#endif
// 如果设置了user指令,而且使用root权限启动会在这里改变进程所属的用户和组
if (geteuid() == 0) {
if (setgid(ccf->group) == -1) {
ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_errno,
"setgid(%d) failed", ccf->group);
/* fatal */
exit(2);
}
if (initgroups(ccf->username, ccf->group) == -1) {
ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_errno,
"initgroups(%s, %d) failed",
ccf->username, ccf->group);
}
if (setuid(ccf->user) == -1) {
ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_errno,
"setuid(%d) failed", ccf->user);
/* fatal */
exit(2);
}
}
if (worker >= 0) {
// 获取这个worker对应的CPU号
cpu_affinity = ngx_get_cpu_affinity(worker);
// 绑定这个worker对应的CPU。
if (cpu_affinity) {
ngx_setaffinity(cpu_affinity, cycle->log);
}
}
#if (NGX_HAVE_PR_SET_DUMPABLE)
/* allow coredump after setuid() in Linux 2.4.x */
if (prctl(PR_SET_DUMPABLE, 1, 0, 0, 0) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"prctl(PR_SET_DUMPABLE) failed");
}
#endif
// 设置工作目录
if (ccf->working_directory.len) {
if (chdir((char *) ccf->working_directory.data) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"chdir(\"%s\") failed", ccf->working_directory.data);
/* fatal */
exit(2);
}
}
sigemptyset(&set);
// 把父进程设置为阻塞的信号重新设置为可接收状态。
if (sigprocmask(SIG_SETMASK, &set, NULL) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"sigprocmask() failed");
}
// 设置随机数种子。
srandom((ngx_pid << 16) ^ ngx_time());
/*
* disable deleting previous events for the listening sockets because
* in the worker processes there are no events at all at this point
*/
ls = cycle->listening.elts;
for (i = 0; i < cycle->listening.nelts; i++) {
ls[i].previous = NULL;
}
// 调用每个模块的init_process函数
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);
}
}
}
// 关闭其他子进程与maser进程通信的unix套接字
for (n = 0; n < ngx_last_process; n++) {
if (ngx_processes[n].pid == -1) {
continue;
}
if (n == ngx_process_slot) {
continue;
}
if (ngx_processes[n].channel[1] == -1) {
continue;
}
if (close(ngx_processes[n].channel[1]) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"close() channel failed");
}
}
// 关闭unix套接字对的父进程端套接字
if (close(ngx_processes[ngx_process_slot].channel[0]) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"close() channel failed");
}
#if 0
ngx_last_process = 0;
#endif
// 将这个进程接收父进程消息套接字的接收事件放到事件模型中，
// 并将回调函数设置为ngx_channel_handler
if (ngx_add_channel_event(cycle, ngx_channel, NGX_READ_EVENT,
ngx_channel_handler)
== NGX_ERROR)
{
/* fatal */
exit(2);
}
}
