| |
| /* |
| * Copyright (C) Igor Sysoev |
| * Copyright (C) Nginx, Inc. |
| */ |
| |
| |
| #include <ngx_config.h> |
| #include <ngx_core.h> |
| #include <ngx_event.h> |
| |
| |
| #if (NGX_TEST_BUILD_RTSIG) |
| |
| #ifdef SIGRTMIN |
| #define si_fd _reason.__spare__.__spare2__[0] |
| #else |
| #define SIGRTMIN 33 |
| #define si_fd __spare__[0] |
| #endif |
| |
| #define F_SETSIG 10 |
| #define KERN_RTSIGNR 30 |
| #define KERN_RTSIGMAX 31 |
| |
| int sigtimedwait(const sigset_t *set, siginfo_t *info, |
| const struct timespec *timeout) |
| { |
| return -1; |
| } |
| |
| int ngx_linux_rtsig_max; |
| |
| #endif |
| |
| |
| typedef struct { |
| ngx_uint_t signo; |
| ngx_uint_t overflow_events; |
| ngx_uint_t overflow_test; |
| ngx_uint_t overflow_threshold; |
| } ngx_rtsig_conf_t; |
| |
| |
| extern ngx_event_module_t ngx_poll_module_ctx; |
| |
| static ngx_int_t ngx_rtsig_init(ngx_cycle_t *cycle, ngx_msec_t timer); |
| static void ngx_rtsig_done(ngx_cycle_t *cycle); |
| static ngx_int_t ngx_rtsig_add_connection(ngx_connection_t *c); |
| static ngx_int_t ngx_rtsig_del_connection(ngx_connection_t *c, |
| ngx_uint_t flags); |
| static ngx_int_t ngx_rtsig_process_events(ngx_cycle_t *cycle, |
| ngx_msec_t timer, ngx_uint_t flags); |
| static ngx_int_t ngx_rtsig_process_overflow(ngx_cycle_t *cycle, |
| ngx_msec_t timer, ngx_uint_t flags); |
| |
| static void *ngx_rtsig_create_conf(ngx_cycle_t *cycle); |
| static char *ngx_rtsig_init_conf(ngx_cycle_t *cycle, void *conf); |
| static char *ngx_check_ngx_overflow_threshold_bounds(ngx_conf_t *cf, |
| void *post, void *data); |
| |
| |
| static sigset_t set; |
| static ngx_uint_t overflow, overflow_current; |
| static struct pollfd *overflow_list; |
| |
| |
| static ngx_str_t rtsig_name = ngx_string("rtsig"); |
| |
| static ngx_conf_num_bounds_t ngx_overflow_threshold_bounds = { |
| ngx_check_ngx_overflow_threshold_bounds, 2, 10 |
| }; |
| |
| |
| static ngx_command_t ngx_rtsig_commands[] = { |
| |
| { ngx_string("rtsig_signo"), |
| NGX_EVENT_CONF|NGX_CONF_TAKE1, |
| ngx_conf_set_num_slot, |
| 0, |
| offsetof(ngx_rtsig_conf_t, signo), |
| NULL }, |
| |
| { ngx_string("rtsig_overflow_events"), |
| NGX_EVENT_CONF|NGX_CONF_TAKE1, |
| ngx_conf_set_num_slot, |
| 0, |
| offsetof(ngx_rtsig_conf_t, overflow_events), |
| NULL }, |
| |
| { ngx_string("rtsig_overflow_test"), |
| NGX_EVENT_CONF|NGX_CONF_TAKE1, |
| ngx_conf_set_num_slot, |
| 0, |
| offsetof(ngx_rtsig_conf_t, overflow_test), |
| NULL }, |
| |
| { ngx_string("rtsig_overflow_threshold"), |
| NGX_EVENT_CONF|NGX_CONF_TAKE1, |
| ngx_conf_set_num_slot, |
| 0, |
| offsetof(ngx_rtsig_conf_t, overflow_threshold), |
| &ngx_overflow_threshold_bounds }, |
| |
| ngx_null_command |
| }; |
| |
| |
| ngx_event_module_t ngx_rtsig_module_ctx = { |
| &rtsig_name, |
| ngx_rtsig_create_conf, /* create configuration */ |
| ngx_rtsig_init_conf, /* init configuration */ |
| |
| { |
| NULL, /* add an event */ |
| NULL, /* delete an event */ |
| NULL, /* enable an event */ |
| NULL, /* disable an event */ |
| ngx_rtsig_add_connection, /* add an connection */ |
| ngx_rtsig_del_connection, /* delete an connection */ |
| NULL, /* process the changes */ |
| ngx_rtsig_process_events, /* process the events */ |
| ngx_rtsig_init, /* init the events */ |
| ngx_rtsig_done, /* done the events */ |
| } |
| |
| }; |
| |
| ngx_module_t ngx_rtsig_module = { |
| NGX_MODULE_V1, |
| &ngx_rtsig_module_ctx, /* module context */ |
| ngx_rtsig_commands, /* module directives */ |
| NGX_EVENT_MODULE, /* module type */ |
| NULL, /* init master */ |
| NULL, /* init module */ |
| NULL, /* init process */ |
| NULL, /* init thread */ |
| NULL, /* exit thread */ |
| NULL, /* exit process */ |
| NULL, /* exit master */ |
| NGX_MODULE_V1_PADDING |
| }; |
| |
| |
| static ngx_int_t |
| ngx_rtsig_init(ngx_cycle_t *cycle, ngx_msec_t timer) |
| { |
| ngx_rtsig_conf_t *rtscf; |
| |
| rtscf = ngx_event_get_conf(cycle->conf_ctx, ngx_rtsig_module); |
| |
| sigemptyset(&set); |
| sigaddset(&set, (int) rtscf->signo); |
| sigaddset(&set, (int) rtscf->signo + 1); |
| sigaddset(&set, SIGIO); |
| sigaddset(&set, SIGALRM); |
| |
| if (sigprocmask(SIG_BLOCK, &set, NULL) == -1) { |
| ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_errno, |
| "sigprocmask() failed"); |
| return NGX_ERROR; |
| } |
| |
| if (overflow_list) { |
| ngx_free(overflow_list); |
| } |
| |
| overflow_list = ngx_alloc(sizeof(struct pollfd) * rtscf->overflow_events, |
| cycle->log); |
| if (overflow_list == NULL) { |
| return NGX_ERROR; |
| } |
| |
| ngx_io = ngx_os_io; |
| |
| ngx_event_actions = ngx_rtsig_module_ctx.actions; |
| |
| ngx_event_flags = NGX_USE_RTSIG_EVENT |
| |NGX_USE_GREEDY_EVENT |
| |NGX_USE_FD_EVENT; |
| |
| return NGX_OK; |
| } |
| |
| |
| static void |
| ngx_rtsig_done(ngx_cycle_t *cycle) |
| { |
| ngx_free(overflow_list); |
| |
| overflow_list = NULL; |
| } |
| |
| |
| static ngx_int_t |
| ngx_rtsig_add_connection(ngx_connection_t *c) |
| { |
| ngx_uint_t signo; |
| ngx_rtsig_conf_t *rtscf; |
| |
| if (c->read->accept && c->read->disabled) { |
| |
| ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0, |
| "rtsig enable connection: fd:%d", c->fd); |
| |
| if (fcntl(c->fd, F_SETOWN, ngx_pid) == -1) { |
| ngx_log_error(NGX_LOG_ALERT, c->log, ngx_errno, |
| "fcntl(F_SETOWN) failed"); |
| return NGX_ERROR; |
| } |
| |
| c->read->active = 1; |
| c->read->disabled = 0; |
| } |
| |
| rtscf = ngx_event_get_conf(ngx_cycle->conf_ctx, ngx_rtsig_module); |
| |
| signo = rtscf->signo + c->read->instance; |
| |
| ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0, |
| "rtsig add connection: fd:%d signo:%ui", c->fd, signo); |
| |
| if (fcntl(c->fd, F_SETFL, O_RDWR|O_NONBLOCK|O_ASYNC) == -1) { |
| ngx_log_error(NGX_LOG_ALERT, c->log, ngx_errno, |
| "fcntl(O_RDWR|O_NONBLOCK|O_ASYNC) failed"); |
| return NGX_ERROR; |
| } |
| |
| if (fcntl(c->fd, F_SETSIG, (int) signo) == -1) { |
| ngx_log_error(NGX_LOG_ALERT, c->log, ngx_errno, |
| "fcntl(F_SETSIG) failed"); |
| return NGX_ERROR; |
| } |
| |
| if (fcntl(c->fd, F_SETOWN, ngx_pid) == -1) { |
| ngx_log_error(NGX_LOG_ALERT, c->log, ngx_errno, |
| "fcntl(F_SETOWN) failed"); |
| return NGX_ERROR; |
| } |
| |
| #if (NGX_HAVE_ONESIGFD) |
| if (fcntl(c->fd, F_SETAUXFL, O_ONESIGFD) == -1) { |
| ngx_log_error(NGX_LOG_ALERT, c->log, ngx_errno, |
| "fcntl(F_SETAUXFL) failed"); |
| return NGX_ERROR; |
| } |
| #endif |
| |
| c->read->active = 1; |
| c->write->active = 1; |
| |
| return NGX_OK; |
| } |
| |
| |
| static ngx_int_t |
| ngx_rtsig_del_connection(ngx_connection_t *c, ngx_uint_t flags) |
| { |
| ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0, |
| "rtsig del connection: fd:%d", c->fd); |
| |
| if ((flags & NGX_DISABLE_EVENT) && c->read->accept) { |
| |
| ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0, |
| "rtsig disable connection: fd:%d", c->fd); |
| |
| c->read->active = 0; |
| c->read->disabled = 1; |
| return NGX_OK; |
| } |
| |
| if (flags & NGX_CLOSE_EVENT) { |
| c->read->active = 0; |
| c->write->active = 0; |
| return NGX_OK; |
| } |
| |
| if (fcntl(c->fd, F_SETFL, O_RDWR|O_NONBLOCK) == -1) { |
| ngx_log_error(NGX_LOG_ALERT, c->log, ngx_errno, |
| "fcntl(O_RDWR|O_NONBLOCK) failed"); |
| return NGX_ERROR; |
| } |
| |
| c->read->active = 0; |
| c->write->active = 0; |
| |
| return NGX_OK; |
| } |
| |
| |
| static ngx_int_t |
| ngx_rtsig_process_events(ngx_cycle_t *cycle, ngx_msec_t timer, ngx_uint_t flags) |
| { |
| int signo; |
| ngx_int_t instance; |
| ngx_err_t err; |
| siginfo_t si; |
| ngx_event_t *rev, *wev, **queue; |
| struct timespec ts, *tp; |
| struct sigaction sa; |
| ngx_connection_t *c; |
| ngx_rtsig_conf_t *rtscf; |
| |
| if (timer == NGX_TIMER_INFINITE) { |
| tp = NULL; |
| |
| } else { |
| ts.tv_sec = timer / 1000; |
| ts.tv_nsec = (timer % 1000) * 1000000; |
| tp = &ts; |
| } |
| |
| ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0, |
| "rtsig timer: %M", timer); |
| |
| /* Linux's sigwaitinfo() is sigtimedwait() with the NULL timeout pointer */ |
| |
| signo = sigtimedwait(&set, &si, tp); |
| |
| if (signo == -1) { |
| err = ngx_errno; |
| |
| ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, err, |
| "rtsig signo:%d", signo); |
| |
| if (flags & NGX_UPDATE_TIME) { |
| ngx_time_update(); |
| } |
| |
| if (err == NGX_EAGAIN) { |
| |
| /* timeout */ |
| |
| if (timer != NGX_TIMER_INFINITE) { |
| return NGX_AGAIN; |
| } |
| |
| ngx_log_error(NGX_LOG_ALERT, cycle->log, err, |
| "sigtimedwait() returned EAGAIN without timeout"); |
| return NGX_ERROR; |
| } |
| |
| ngx_log_error((err == NGX_EINTR) ? NGX_LOG_INFO : NGX_LOG_ALERT, |
| cycle->log, err, "sigtimedwait() failed"); |
| return NGX_ERROR; |
| } |
| |
| ngx_log_debug3(NGX_LOG_DEBUG_EVENT, cycle->log, 0, |
| "rtsig signo:%d fd:%d band:%04Xd", |
| signo, si.si_fd, si.si_band); |
| |
| if (flags & NGX_UPDATE_TIME) { |
| ngx_time_update(); |
| } |
| |
| rtscf = ngx_event_get_conf(ngx_cycle->conf_ctx, ngx_rtsig_module); |
| |
| if (signo == (int) rtscf->signo || signo == (int) rtscf->signo + 1) { |
| |
| if (overflow && (ngx_uint_t) si.si_fd > overflow_current) { |
| return NGX_OK; |
| } |
| |
| c = ngx_cycle->files[si.si_fd]; |
| |
| if (c == NULL) { |
| |
| /* the stale event */ |
| |
| return NGX_OK; |
| } |
| |
| instance = signo - (int) rtscf->signo; |
| |
| rev = c->read; |
| |
| if (rev->instance != instance) { |
| |
| /* |
| * the stale event from a file descriptor |
| * that was just closed in this iteration |
| */ |
| |
| ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0, |
| "rtsig: stale event %p", c); |
| |
| return NGX_OK; |
| } |
| |
| if ((si.si_band & (POLLIN|POLLHUP|POLLERR)) && rev->active) { |
| |
| rev->ready = 1; |
| |
| if (flags & NGX_POST_EVENTS) { |
| queue = (ngx_event_t **) (rev->accept ? |
| &ngx_posted_accept_events : &ngx_posted_events); |
| |
| ngx_locked_post_event(rev, queue); |
| |
| } else { |
| rev->handler(rev); |
| } |
| } |
| |
| wev = c->write; |
| |
| if ((si.si_band & (POLLOUT|POLLHUP|POLLERR)) && wev->active) { |
| |
| wev->ready = 1; |
| |
| if (flags & NGX_POST_EVENTS) { |
| ngx_locked_post_event(wev, &ngx_posted_events); |
| |
| } else { |
| wev->handler(wev); |
| } |
| } |
| |
| return NGX_OK; |
| |
| } else if (signo == SIGALRM) { |
| |
| ngx_time_update(); |
| |
| return NGX_OK; |
| |
| } else if (signo == SIGIO) { |
| |
| ngx_log_error(NGX_LOG_ALERT, cycle->log, 0, |
| "rt signal queue overflowed"); |
| |
| /* flush the RT signal queue */ |
| |
| ngx_memzero(&sa, sizeof(struct sigaction)); |
| sa.sa_handler = SIG_DFL; |
| sigemptyset(&sa.sa_mask); |
| |
| if (sigaction(rtscf->signo, &sa, NULL) == -1) { |
| ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno, |
| "sigaction(%d, SIG_DFL) failed", rtscf->signo); |
| } |
| |
| if (sigaction(rtscf->signo + 1, &sa, NULL) == -1) { |
| ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno, |
| "sigaction(%d, SIG_DFL) failed", rtscf->signo + 1); |
| } |
| |
| overflow = 1; |
| overflow_current = 0; |
| ngx_event_actions.process_events = ngx_rtsig_process_overflow; |
| |
| return NGX_ERROR; |
| |
| } |
| |
| ngx_log_error(NGX_LOG_ALERT, cycle->log, 0, |
| "sigtimedwait() returned unexpected signal: %d", signo); |
| |
| return NGX_ERROR; |
| } |
| |
| |
| static ngx_int_t |
| ngx_rtsig_process_overflow(ngx_cycle_t *cycle, ngx_msec_t timer, |
| ngx_uint_t flags) |
| { |
| int name[2], rtsig_max, rtsig_nr, events, ready; |
| size_t len; |
| ngx_err_t err; |
| ngx_uint_t tested, n, i; |
| ngx_event_t *rev, *wev, **queue; |
| ngx_connection_t *c; |
| ngx_rtsig_conf_t *rtscf; |
| |
| ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0, |
| "rtsig process overflow"); |
| |
| rtscf = ngx_event_get_conf(ngx_cycle->conf_ctx, ngx_rtsig_module); |
| |
| tested = 0; |
| |
| for ( ;; ) { |
| |
| n = 0; |
| while (n < rtscf->overflow_events) { |
| |
| if (overflow_current == cycle->connection_n) { |
| break; |
| } |
| |
| c = cycle->files[overflow_current++]; |
| |
| if (c == NULL || c->fd == -1) { |
| continue; |
| } |
| |
| events = 0; |
| |
| if (c->read->active && c->read->handler) { |
| events |= POLLIN; |
| } |
| |
| if (c->write->active && c->write->handler) { |
| events |= POLLOUT; |
| } |
| |
| if (events == 0) { |
| continue; |
| } |
| |
| overflow_list[n].fd = c->fd; |
| overflow_list[n].events = events; |
| overflow_list[n].revents = 0; |
| n++; |
| } |
| |
| if (n == 0) { |
| break; |
| } |
| |
| for ( ;; ) { |
| ready = poll(overflow_list, n, 0); |
| |
| ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0, |
| "rtsig overflow poll:%d", ready); |
| |
| if (ready == -1) { |
| err = ngx_errno; |
| ngx_log_error((err == NGX_EINTR) ? NGX_LOG_INFO : NGX_LOG_ALERT, |
| cycle->log, 0, |
| "poll() failed while the overflow recover"); |
| |
| if (err == NGX_EINTR) { |
| continue; |
| } |
| } |
| |
| break; |
| } |
| |
| if (ready <= 0) { |
| continue; |
| } |
| |
| ngx_mutex_lock(ngx_posted_events_mutex); |
| |
| for (i = 0; i < n; i++) { |
| c = cycle->files[overflow_list[i].fd]; |
| |
| if (c == NULL) { |
| continue; |
| } |
| |
| rev = c->read; |
| |
| if (rev->active |
| && !rev->closed |
| && rev->handler |
| && (overflow_list[i].revents |
| & (POLLIN|POLLERR|POLLHUP|POLLNVAL))) |
| { |
| tested++; |
| |
| if ((flags & NGX_POST_THREAD_EVENTS) && !rev->accept) { |
| rev->posted_ready = 1; |
| |
| } else { |
| rev->ready = 1; |
| } |
| |
| if (flags & NGX_POST_EVENTS) { |
| queue = (ngx_event_t **) (rev->accept ? |
| &ngx_posted_accept_events : &ngx_posted_events); |
| |
| ngx_locked_post_event(rev, queue); |
| |
| } else { |
| rev->handler(rev); |
| } |
| } |
| |
| wev = c->write; |
| |
| if (wev->active |
| && !wev->closed |
| && wev->handler |
| && (overflow_list[i].revents |
| & (POLLOUT|POLLERR|POLLHUP|POLLNVAL))) |
| { |
| tested++; |
| |
| if (flags & NGX_POST_THREAD_EVENTS) { |
| wev->posted_ready = 1; |
| |
| } else { |
| wev->ready = 1; |
| } |
| |
| if (flags & NGX_POST_EVENTS) { |
| ngx_locked_post_event(wev, &ngx_posted_events); |
| |
| } else { |
| wev->handler(wev); |
| } |
| } |
| } |
| |
| ngx_mutex_unlock(ngx_posted_events_mutex); |
| |
| if (tested >= rtscf->overflow_test) { |
| |
| if (ngx_linux_rtsig_max) { |
| |
| /* |
| * Check the current rt queue length to prevent |
| * the new overflow. |
| * |
| * learn the "/proc/sys/kernel/rtsig-max" value because |
| * it can be changed since the last checking |
| */ |
| |
| name[0] = CTL_KERN; |
| name[1] = KERN_RTSIGMAX; |
| len = sizeof(rtsig_max); |
| |
| if (sysctl(name, 2, &rtsig_max, &len, NULL, 0) == -1) { |
| ngx_log_error(NGX_LOG_ALERT, cycle->log, errno, |
| "sysctl(KERN_RTSIGMAX) failed"); |
| return NGX_ERROR; |
| } |
| |
| /* name[0] = CTL_KERN; */ |
| name[1] = KERN_RTSIGNR; |
| len = sizeof(rtsig_nr); |
| |
| if (sysctl(name, 2, &rtsig_nr, &len, NULL, 0) == -1) { |
| ngx_log_error(NGX_LOG_ALERT, cycle->log, errno, |
| "sysctl(KERN_RTSIGNR) failed"); |
| return NGX_ERROR; |
| } |
| |
| /* |
| * drain the rt signal queue if the /"proc/sys/kernel/rtsig-nr" |
| * is bigger than |
| * "/proc/sys/kernel/rtsig-max" / "rtsig_overflow_threshold" |
| */ |
| |
| if (rtsig_max / (int) rtscf->overflow_threshold < rtsig_nr) { |
| ngx_log_debug2(NGX_LOG_DEBUG_EVENT, cycle->log, 0, |
| "rtsig queue state: %d/%d", |
| rtsig_nr, rtsig_max); |
| while (ngx_rtsig_process_events(cycle, 0, flags) == NGX_OK) |
| { |
| /* void */ |
| } |
| } |
| |
| } else { |
| |
| /* |
| * Linux has not KERN_RTSIGMAX since 2.6.6-mm2 |
| * so drain the rt signal queue unconditionally |
| */ |
| |
| while (ngx_rtsig_process_events(cycle, 0, flags) == NGX_OK) { |
| /* void */ |
| } |
| } |
| |
| tested = 0; |
| } |
| } |
| |
| if (flags & NGX_UPDATE_TIME) { |
| ngx_time_update(); |
| } |
| |
| ngx_log_error(NGX_LOG_ALERT, cycle->log, 0, |
| "rt signal queue overflow recovered"); |
| |
| overflow = 0; |
| ngx_event_actions.process_events = ngx_rtsig_process_events; |
| |
| return NGX_OK; |
| } |
| |
| |
| static void * |
| ngx_rtsig_create_conf(ngx_cycle_t *cycle) |
| { |
| ngx_rtsig_conf_t *rtscf; |
| |
| rtscf = ngx_palloc(cycle->pool, sizeof(ngx_rtsig_conf_t)); |
| if (rtscf == NULL) { |
| return NULL; |
| } |
| |
| rtscf->signo = NGX_CONF_UNSET; |
| rtscf->overflow_events = NGX_CONF_UNSET; |
| rtscf->overflow_test = NGX_CONF_UNSET; |
| rtscf->overflow_threshold = NGX_CONF_UNSET; |
| |
| return rtscf; |
| } |
| |
| |
| static char * |
| ngx_rtsig_init_conf(ngx_cycle_t *cycle, void *conf) |
| { |
| ngx_rtsig_conf_t *rtscf = conf; |
| |
| /* LinuxThreads use the first 3 RT signals */ |
| ngx_conf_init_uint_value(rtscf->signo, SIGRTMIN + 10); |
| |
| ngx_conf_init_uint_value(rtscf->overflow_events, 16); |
| ngx_conf_init_uint_value(rtscf->overflow_test, 32); |
| ngx_conf_init_uint_value(rtscf->overflow_threshold, 10); |
| |
| return NGX_CONF_OK; |
| } |
| |
| |
| static char * |
| ngx_check_ngx_overflow_threshold_bounds(ngx_conf_t *cf, void *post, void *data) |
| { |
| if (ngx_linux_rtsig_max) { |
| return ngx_conf_check_num_bounds(cf, post, data); |
| } |
| |
| ngx_conf_log_error(NGX_LOG_WARN, cf, 0, |
| "\"rtsig_overflow_threshold\" is not supported " |
| "since Linux 2.6.6-mm2, ignored"); |
| |
| return NGX_CONF_OK; |
| } |
