int fpm_children_make(struct fpm_worker_pool_s *wp, int in_event_loop, int nb_to_spawn, int is_debug) /* {{{ */
{
pid_t pid;
struct fpm_child_s *child;
int max;
if (wp->config->pm == PM_STYLE_DYNAMIC) {
if (!in_event_loop) { /* starting */
max = wp->config->pm_start_servers;
} else {
max = wp->running_children + nb_to_spawn;
}
} else { /* PM_STYLE_STATIC */
max = wp->config->pm_max_children;
}
while (fpm_pctl_can_spawn_children() && wp->running_children < max) {
child = fpm_resources_prepare(wp);
if (!child) {
return 2;
}
pid = fork();
switch (pid) {
case 0 :
fpm_child_resources_use(child);
fpm_globals.is_child = 1;
fpm_child_init(wp);
return 0;
case -1 :
zlog(ZLOG_SYSERROR, "fork() failed");
fpm_resources_discard(child);
return 2;
default :
child->pid = pid;
fpm_clock_get(&child->started);
fpm_parent_resources_use(child);
zlog(is_debug ? ZLOG_DEBUG : ZLOG_NOTICE, "[pool %s] child %d started", wp->config->name, (int) pid);
}
}
return 1; /* we are done */
}
int fpm_children_make(struct fpm_worker_pool_s *wp, int in_event_loop, int nb_to_spawn, int is_debug) /* {{{ */
{
pid_t pid;
struct fpm_child_s *child;
int max;
static int warned = 0;
//动态模式
if (wp->config->pm == PM_STYLE_DYNAMIC) {
if (!in_event_loop) { /* starting */
max = wp->config->pm_start_servers;
} else {
max = wp->running_children + nb_to_spawn;
}
} else if (wp->config->pm == PM_STYLE_ONDEMAND) {
//ondemand模式
if (!in_event_loop) { /* starting */
max = 0; /* do not create any child at startup */
} else {
max = wp->running_children + nb_to_spawn;
}
} else { /* PM_STYLE_STATIC */
//静态模式
max = wp->config->pm_max_children;
}
/*
* fork children while:
* - fpm_pctl_can_spawn_children : FPM is running in a NORMAL state (aka not restart, stop or reload)
* - wp->running_children < max : there is less than the max process for the current pool
* - (fpm_global_config.process_max < 1 || fpm_globals.running_children < fpm_global_config.process_max):
* if fpm_global_config.process_max is set, FPM has not fork this number of processes (globaly)
*/
//当执行restart、stop、reload命令时，fpm_pctl_can_spawn_children()为false
while (fpm_pctl_can_spawn_children() && wp->running_children < max && (fpm_global_config.process_max < 1 || fpm_globals.running_children < fpm_global_config.process_max)) {
warned = 0;
child = fpm_resources_prepare(wp);
if (!child) {
return 2;
}
//fork子进程
pid = fork();
switch (pid) {
case 0 :
fpm_child_resources_use(child);
fpm_globals.is_child = 1;
//子进程初始化
fpm_child_init(wp);
return 0;
case -1 :
zlog(ZLOG_SYSERROR, "fork() failed");
fpm_resources_discard(child);
return 2;
default :
child->pid = pid;
fpm_clock_get(&child->started);
fpm_parent_resources_use(child);
zlog(is_debug ? ZLOG_DEBUG : ZLOG_NOTICE, "[pool %s] child %d started", wp->config->name, (int) pid);
}
}
if (!warned && fpm_global_config.process_max > 0 && fpm_globals.running_children >= fpm_global_config.process_max) {
warned = 1;
zlog(ZLOG_WARNING, "The maximum number of processes has been reached. Please review your configuration and consider raising 'process.max'");
}
return 1; /* we are done */
}
void fpm_children_bury() /* {{{ */
{
int status;
pid_t pid;
struct fpm_child_s *child;
while ( (pid = waitpid(-1, &status, WNOHANG | WUNTRACED)) > 0) {
char buf[128];
int severity = ZLOG_NOTICE;
int restart_child = 1;
child = fpm_child_find(pid);
/*
WIFEXITED(status)如果子进程正常结束则为非0值。
WEXITSTATUS(status)取得子进程exit()返回的结束代码，一般会先用WIFEXITED 来判断是否正常结束才能使用此宏。
WIFSIGNALED(status)如果子进程是因为信号而结束则此宏值为真
WTERMSIG(status)取得子进程因信号而中止的信号代码，一般会先用WIFSIGNALED 来判断后才使用此宏。
WIFSTOPPED(status)如果子进程处于暂停执行情况则此宏值为真。一般只有使用WUNTRACED 时才会有此情况。
WSTOPSIG(status)取得引发子进程暂停的信号代码，
*/
if (WIFEXITED(status)) {
snprintf(buf, sizeof(buf), "with code %d", WEXITSTATUS(status));
/* if it's been killed because of dynamic process management
* don't restart it automaticaly
*/
if (child && child->idle_kill) {
restart_child = 0;
}
if (WEXITSTATUS(status) != FPM_EXIT_OK) {
severity = ZLOG_WARNING;
}
} else if (WIFSIGNALED(status)) {
const char *signame = fpm_signal_names[WTERMSIG(status)];
const char *have_core = WCOREDUMP(status) ? " - core dumped" : "";
if (signame == NULL) {
signame = "";
}
snprintf(buf, sizeof(buf), "on signal %d (%s%s)", WTERMSIG(status), signame, have_core);
/* if it's been killed because of dynamic process management
* don't restart it automaticaly
*/
if (child && child->idle_kill && WTERMSIG(status) == SIGQUIT) {
restart_child = 0;
}
if (WTERMSIG(status) != SIGQUIT) { /* possible request loss */
severity = ZLOG_WARNING;
}
} else if (WIFSTOPPED(status)) {
zlog(ZLOG_NOTICE, "child %d stopped for tracing", (int) pid);
//回调 php_trace.c
if (child && child->tracer) {
child->tracer(child);
}
continue;
}
if (child) {
struct fpm_worker_pool_s *wp = child->wp;
struct timeval tv1, tv2;
fpm_child_unlink(child);
//释放scoreboard
fpm_scoreboard_proc_free(wp->scoreboard, child->scoreboard_i);
fpm_clock_get(&tv1);
timersub(&tv1, &child->started, &tv2);
if (restart_child) {
if (!fpm_pctl_can_spawn_children()) {
severity = ZLOG_DEBUG;
}
zlog(severity, "[pool %s] child %d exited %s after %ld.%06d seconds from start", child->wp->config->name, (int) pid, buf, tv2.tv_sec, (int) tv2.tv_usec);
} else {
zlog(ZLOG_DEBUG, "[pool %s] child %d has been killed by the process managment after %ld.%06d seconds from start", child->wp->config->name, (int) pid, tv2.tv_sec, (int) tv2.tv_usec);
}
fpm_child_close(child, 1 /* in event_loop */);
fpm_pctl_child_exited();
if (last_faults && (WTERMSIG(status) == SIGSEGV || WTERMSIG(status) == SIGBUS)) {
time_t now = tv1.tv_sec;
int restart_condition = 1;
int i;
last_faults[fault++] = now;
if (fault == fpm_global_config.emergency_restart_threshold) {
fault = 0;
}
for (i = 0; i < fpm_global_config.emergency_restart_threshold; i++) {
if (now - last_faults[i] > fpm_global_config.emergency_restart_interval) {
restart_condition = 0;
break;
}
}
if (restart_condition) {
zlog(ZLOG_WARNING, "failed processes threshold (%d in %d sec) is reached, initiating reload", fpm_global_config.emergency_restart_threshold, fpm_global_config.emergency_restart_interval);
fpm_pctl(FPM_PCTL_STATE_RELOADING, FPM_PCTL_ACTION_SET);
}
}
if (restart_child) {
fpm_children_make(wp, 1 /* in event loop */, 1, 0);
if (fpm_globals.is_child) {
break;
}
}
} else {
zlog(ZLOG_ALERT, "oops, unknown child (%d) exited %s. Please open a bug report (https://bugs.php.net).", pid, buf);
}
}
}
