diff --git a/src/core/manager.c b/src/core/manager.c index e8140464eb..2dec25b0d4 100644 --- a/src/core/manager.c +++ b/src/core/manager.c @@ -109,6 +109,7 @@ static int manager_dispatch_idle_pipe_fd(sd_event_source *source, int fd, uint32 static int manager_dispatch_user_lookup_fd(sd_event_source *source, int fd, uint32_t revents, void *userdata); static int manager_dispatch_jobs_in_progress(sd_event_source *source, usec_t usec, void *userdata); static int manager_dispatch_run_queue(sd_event_source *source, void *userdata); +static int manager_dispatch_sigchld(sd_event_source *source, void *userdata); static int manager_run_environment_generators(Manager *m); static int manager_run_generators(Manager *m); @@ -634,6 +635,29 @@ static int manager_setup_run_queue(Manager *m) { return 0; } +static int manager_setup_sigchld_event_source(Manager *m) { + int r; + + assert(m); + assert(!m->sigchld_event_source); + + r = sd_event_add_defer(m->event, &m->sigchld_event_source, manager_dispatch_sigchld, m); + if (r < 0) + return r; + + r = sd_event_source_set_priority(m->sigchld_event_source, SD_EVENT_PRIORITY_NORMAL-7); + if (r < 0) + return r; + + r = sd_event_source_set_enabled(m->sigchld_event_source, SD_EVENT_OFF); + if (r < 0) + return r; + + (void) sd_event_source_set_description(m->sigchld_event_source, "manager-sigchld"); + + return 0; +} + int manager_new(UnitFileScope scope, unsigned test_run_flags, Manager **_m) { Manager *m; int r; @@ -734,6 +758,10 @@ int manager_new(UnitFileScope scope, unsigned test_run_flags, Manager **_m) { if (r < 0) goto fail; + r = manager_setup_sigchld_event_source(m); + if (r < 0) + goto fail; + m->udev = udev_new(); if (!m->udev) { r = -ENOMEM; @@ -817,7 +845,7 @@ static int manager_setup_notify(Manager *m) { /* Process notification messages a bit earlier than SIGCHLD, so that we can still identify to which * service an exit message belongs. */ - r = sd_event_source_set_priority(m->notify_event_source, SD_EVENT_PRIORITY_NORMAL-7); + r = sd_event_source_set_priority(m->notify_event_source, SD_EVENT_PRIORITY_NORMAL-8); if (r < 0) return log_error_errno(r, "Failed to set priority of notify event source: %m"); @@ -1185,6 +1213,7 @@ Manager* manager_free(Manager *m) { set_free(m->failed_units); sd_event_source_unref(m->signal_event_source); + sd_event_source_unref(m->sigchld_event_source); sd_event_source_unref(m->notify_event_source); sd_event_source_unref(m->cgroups_agent_event_source); sd_event_source_unref(m->time_change_event_source); @@ -2052,65 +2081,71 @@ static void invoke_sigchld_event(Manager *m, Unit *u, const siginfo_t *si) { } } -static int manager_dispatch_sigchld(Manager *m) { +static int manager_dispatch_sigchld(sd_event_source *source, void *userdata) { + Manager *m = userdata; + siginfo_t si = {}; + int r; + + assert(source); assert(m); - for (;;) { - siginfo_t si = {}; + /* First we call waitd() for a PID and do not reap the zombie. That way we can still access /proc/$PID for it + * while it is a zombie. */ - /* First we call waitd() for a PID and do not reap the - * zombie. That way we can still access /proc/$PID for - * it while it is a zombie. */ - if (waitid(P_ALL, 0, &si, WEXITED|WNOHANG|WNOWAIT) < 0) { + if (waitid(P_ALL, 0, &si, WEXITED|WNOHANG|WNOWAIT) < 0) { - if (errno == ECHILD) - break; + if (errno == ECHILD) + goto turn_off; - if (errno == EINTR) - continue; - - return -errno; - } - - if (si.si_pid <= 0) - break; - - if (IN_SET(si.si_code, CLD_EXITED, CLD_KILLED, CLD_DUMPED)) { - _cleanup_free_ char *name = NULL; - Unit *u1, *u2, *u3; - - get_process_comm(si.si_pid, &name); - - log_debug("Child "PID_FMT" (%s) died (code=%s, status=%i/%s)", - si.si_pid, strna(name), - sigchld_code_to_string(si.si_code), - si.si_status, - strna(si.si_code == CLD_EXITED - ? exit_status_to_string(si.si_status, EXIT_STATUS_FULL) - : signal_to_string(si.si_status))); - - /* And now figure out the unit this belongs - * to, it might be multiple... */ - u1 = manager_get_unit_by_pid_cgroup(m, si.si_pid); - if (u1) - invoke_sigchld_event(m, u1, &si); - u2 = hashmap_get(m->watch_pids1, PID_TO_PTR(si.si_pid)); - if (u2 && u2 != u1) - invoke_sigchld_event(m, u2, &si); - u3 = hashmap_get(m->watch_pids2, PID_TO_PTR(si.si_pid)); - if (u3 && u3 != u2 && u3 != u1) - invoke_sigchld_event(m, u3, &si); - } - - /* And now, we actually reap the zombie. */ - if (waitid(P_PID, si.si_pid, &si, WEXITED) < 0) { - if (errno == EINTR) - continue; - - return -errno; - } + log_error_errno(errno, "Failed to peek for child with waitid(), ignoring: %m"); + return 0; } + if (si.si_pid <= 0) + goto turn_off; + + if (IN_SET(si.si_code, CLD_EXITED, CLD_KILLED, CLD_DUMPED)) { + _cleanup_free_ char *name = NULL; + Unit *u1, *u2, *u3; + + (void) get_process_comm(si.si_pid, &name); + + log_debug("Child "PID_FMT" (%s) died (code=%s, status=%i/%s)", + si.si_pid, strna(name), + sigchld_code_to_string(si.si_code), + si.si_status, + strna(si.si_code == CLD_EXITED + ? exit_status_to_string(si.si_status, EXIT_STATUS_FULL) + : signal_to_string(si.si_status))); + + /* And now figure out the unit this belongs + * to, it might be multiple... */ + u1 = manager_get_unit_by_pid_cgroup(m, si.si_pid); + if (u1) + invoke_sigchld_event(m, u1, &si); + u2 = hashmap_get(m->watch_pids1, PID_TO_PTR(si.si_pid)); + if (u2 && u2 != u1) + invoke_sigchld_event(m, u2, &si); + u3 = hashmap_get(m->watch_pids2, PID_TO_PTR(si.si_pid)); + if (u3 && u3 != u2 && u3 != u1) + invoke_sigchld_event(m, u3, &si); + } + + /* And now, we actually reap the zombie. */ + if (waitid(P_PID, si.si_pid, &si, WEXITED) < 0) { + log_error_errno(errno, "Failed to dequeue child, ignoring: %m"); + return 0; + } + + return 0; + +turn_off: + /* All children processed for now, turn off event source */ + + r = sd_event_source_set_enabled(m->sigchld_event_source, SD_EVENT_OFF); + if (r < 0) + return log_error_errno(r, "Failed to disable SIGCHLD event source: %m"); + return 0; } @@ -2141,7 +2176,6 @@ static int manager_dispatch_signal_fd(sd_event_source *source, int fd, uint32_t Manager *m = userdata; ssize_t n; struct signalfd_siginfo sfsi; - bool sigchld = false; int r; assert(m); @@ -2152,195 +2186,192 @@ static int manager_dispatch_signal_fd(sd_event_source *source, int fd, uint32_t return 0; } - for (;;) { - n = read(m->signal_fd, &sfsi, sizeof(sfsi)); - if (n != sizeof(sfsi)) { - if (n >= 0) { - log_warning("Truncated read from signal fd (%zu bytes)!", n); + n = read(m->signal_fd, &sfsi, sizeof(sfsi)); + if (n != sizeof(sfsi)) { + if (n >= 0) { + log_warning("Truncated read from signal fd (%zu bytes), ignoring!", n); + return 0; + } + + if (IN_SET(errno, EINTR, EAGAIN)) + return 0; + + /* We return an error here, which will kill this handler, + * to avoid a busy loop on read error. */ + return log_error_errno(errno, "Reading from signal fd failed: %m"); + } + + log_received_signal(sfsi.ssi_signo == SIGCHLD || + (sfsi.ssi_signo == SIGTERM && MANAGER_IS_USER(m)) + ? LOG_DEBUG : LOG_INFO, + &sfsi); + + switch (sfsi.ssi_signo) { + + case SIGCHLD: + r = sd_event_source_set_enabled(m->sigchld_event_source, SD_EVENT_ON); + if (r < 0) + log_warning_errno(r, "Failed to enable SIGCHLD even source, ignoring: %m"); + + break; + + case SIGTERM: + if (MANAGER_IS_SYSTEM(m)) { + /* This is for compatibility with the + * original sysvinit */ + r = verify_run_space_and_log("Refusing to reexecute"); + if (r >= 0) + m->exit_code = MANAGER_REEXECUTE; + break; + } + + _fallthrough_; + case SIGINT: + if (MANAGER_IS_SYSTEM(m)) + manager_handle_ctrl_alt_del(m); + else + manager_start_target(m, SPECIAL_EXIT_TARGET, + JOB_REPLACE_IRREVERSIBLY); + break; + + case SIGWINCH: + if (MANAGER_IS_SYSTEM(m)) + manager_start_target(m, SPECIAL_KBREQUEST_TARGET, JOB_REPLACE); + + /* This is a nop on non-init */ + break; + + case SIGPWR: + if (MANAGER_IS_SYSTEM(m)) + manager_start_target(m, SPECIAL_SIGPWR_TARGET, JOB_REPLACE); + + /* This is a nop on non-init */ + break; + + case SIGUSR1: { + Unit *u; + + u = manager_get_unit(m, SPECIAL_DBUS_SERVICE); + + if (!u || UNIT_IS_ACTIVE_OR_RELOADING(unit_active_state(u))) { + log_info("Trying to reconnect to bus..."); + bus_init(m, true); + } + + if (!u || !UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u))) { + log_info("Loading D-Bus service..."); + manager_start_target(m, SPECIAL_DBUS_SERVICE, JOB_REPLACE); + } + + break; + } + + case SIGUSR2: { + _cleanup_free_ char *dump = NULL; + + r = manager_get_dump_string(m, &dump); + if (r < 0) { + log_warning_errno(errno, "Failed to acquire manager dump: %m"); + break; + } + + log_dump(LOG_INFO, dump); + break; + } + + case SIGHUP: + r = verify_run_space_and_log("Refusing to reload"); + if (r >= 0) + m->exit_code = MANAGER_RELOAD; + break; + + default: { + + /* Starting SIGRTMIN+0 */ + static const struct { + const char *target; + JobMode mode; + } target_table[] = { + [0] = { SPECIAL_DEFAULT_TARGET, JOB_ISOLATE }, + [1] = { SPECIAL_RESCUE_TARGET, JOB_ISOLATE }, + [2] = { SPECIAL_EMERGENCY_TARGET, JOB_ISOLATE }, + [3] = { SPECIAL_HALT_TARGET, JOB_REPLACE_IRREVERSIBLY }, + [4] = { SPECIAL_POWEROFF_TARGET, JOB_REPLACE_IRREVERSIBLY }, + [5] = { SPECIAL_REBOOT_TARGET, JOB_REPLACE_IRREVERSIBLY }, + [6] = { SPECIAL_KEXEC_TARGET, JOB_REPLACE_IRREVERSIBLY }, + }; + + /* Starting SIGRTMIN+13, so that target halt and system halt are 10 apart */ + static const ManagerExitCode code_table[] = { + [0] = MANAGER_HALT, + [1] = MANAGER_POWEROFF, + [2] = MANAGER_REBOOT, + [3] = MANAGER_KEXEC, + }; + + if ((int) sfsi.ssi_signo >= SIGRTMIN+0 && + (int) sfsi.ssi_signo < SIGRTMIN+(int) ELEMENTSOF(target_table)) { + int idx = (int) sfsi.ssi_signo - SIGRTMIN; + manager_start_target(m, target_table[idx].target, + target_table[idx].mode); + break; + } + + if ((int) sfsi.ssi_signo >= SIGRTMIN+13 && + (int) sfsi.ssi_signo < SIGRTMIN+13+(int) ELEMENTSOF(code_table)) { + m->exit_code = code_table[sfsi.ssi_signo - SIGRTMIN - 13]; + break; + } + + switch (sfsi.ssi_signo - SIGRTMIN) { + + case 20: + manager_set_show_status(m, SHOW_STATUS_YES); + break; + + case 21: + manager_set_show_status(m, SHOW_STATUS_NO); + break; + + case 22: + log_set_max_level(LOG_DEBUG); + log_info("Setting log level to debug."); + break; + + case 23: + log_set_max_level(LOG_INFO); + log_info("Setting log level to info."); + break; + + case 24: + if (MANAGER_IS_USER(m)) { + m->exit_code = MANAGER_EXIT; return 0; } - if (IN_SET(errno, EINTR, EAGAIN)) - break; + /* This is a nop on init */ + break; - /* We return an error here, which will kill this handler, - * to avoid a busy loop on read error. */ - return log_error_errno(errno, "Reading from signal fd failed: %m"); + case 26: + case 29: /* compatibility: used to be mapped to LOG_TARGET_SYSLOG_OR_KMSG */ + log_set_target(LOG_TARGET_JOURNAL_OR_KMSG); + log_notice("Setting log target to journal-or-kmsg."); + break; + + case 27: + log_set_target(LOG_TARGET_CONSOLE); + log_notice("Setting log target to console."); + break; + + case 28: + log_set_target(LOG_TARGET_KMSG); + log_notice("Setting log target to kmsg."); + break; + + default: + log_warning("Got unhandled signal <%s>.", signal_to_string(sfsi.ssi_signo)); } - - log_received_signal(sfsi.ssi_signo == SIGCHLD || - (sfsi.ssi_signo == SIGTERM && MANAGER_IS_USER(m)) - ? LOG_DEBUG : LOG_INFO, - &sfsi); - - switch (sfsi.ssi_signo) { - - case SIGCHLD: - sigchld = true; - break; - - case SIGTERM: - if (MANAGER_IS_SYSTEM(m)) { - /* This is for compatibility with the - * original sysvinit */ - r = verify_run_space_and_log("Refusing to reexecute"); - if (r >= 0) - m->exit_code = MANAGER_REEXECUTE; - break; - } - - _fallthrough_; - case SIGINT: - if (MANAGER_IS_SYSTEM(m)) - manager_handle_ctrl_alt_del(m); - else - manager_start_target(m, SPECIAL_EXIT_TARGET, - JOB_REPLACE_IRREVERSIBLY); - break; - - case SIGWINCH: - if (MANAGER_IS_SYSTEM(m)) - manager_start_target(m, SPECIAL_KBREQUEST_TARGET, JOB_REPLACE); - - /* This is a nop on non-init */ - break; - - case SIGPWR: - if (MANAGER_IS_SYSTEM(m)) - manager_start_target(m, SPECIAL_SIGPWR_TARGET, JOB_REPLACE); - - /* This is a nop on non-init */ - break; - - case SIGUSR1: { - Unit *u; - - u = manager_get_unit(m, SPECIAL_DBUS_SERVICE); - - if (!u || UNIT_IS_ACTIVE_OR_RELOADING(unit_active_state(u))) { - log_info("Trying to reconnect to bus..."); - bus_init(m, true); - } - - if (!u || !UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u))) { - log_info("Loading D-Bus service..."); - manager_start_target(m, SPECIAL_DBUS_SERVICE, JOB_REPLACE); - } - - break; - } - - case SIGUSR2: { - _cleanup_free_ char *dump = NULL; - - r = manager_get_dump_string(m, &dump); - if (r < 0) { - log_warning_errno(errno, "Failed to acquire manager dump: %m"); - break; - } - - log_dump(LOG_INFO, dump); - break; - } - - case SIGHUP: - r = verify_run_space_and_log("Refusing to reload"); - if (r >= 0) - m->exit_code = MANAGER_RELOAD; - break; - - default: { - - /* Starting SIGRTMIN+0 */ - static const struct { - const char *target; - JobMode mode; - } target_table[] = { - [0] = { SPECIAL_DEFAULT_TARGET, JOB_ISOLATE }, - [1] = { SPECIAL_RESCUE_TARGET, JOB_ISOLATE }, - [2] = { SPECIAL_EMERGENCY_TARGET, JOB_ISOLATE }, - [3] = { SPECIAL_HALT_TARGET, JOB_REPLACE_IRREVERSIBLY }, - [4] = { SPECIAL_POWEROFF_TARGET, JOB_REPLACE_IRREVERSIBLY }, - [5] = { SPECIAL_REBOOT_TARGET, JOB_REPLACE_IRREVERSIBLY }, - [6] = { SPECIAL_KEXEC_TARGET, JOB_REPLACE_IRREVERSIBLY } - }; - - /* Starting SIGRTMIN+13, so that target halt and system halt are 10 apart */ - static const ManagerExitCode code_table[] = { - [0] = MANAGER_HALT, - [1] = MANAGER_POWEROFF, - [2] = MANAGER_REBOOT, - [3] = MANAGER_KEXEC - }; - - if ((int) sfsi.ssi_signo >= SIGRTMIN+0 && - (int) sfsi.ssi_signo < SIGRTMIN+(int) ELEMENTSOF(target_table)) { - int idx = (int) sfsi.ssi_signo - SIGRTMIN; - manager_start_target(m, target_table[idx].target, - target_table[idx].mode); - break; - } - - if ((int) sfsi.ssi_signo >= SIGRTMIN+13 && - (int) sfsi.ssi_signo < SIGRTMIN+13+(int) ELEMENTSOF(code_table)) { - m->exit_code = code_table[sfsi.ssi_signo - SIGRTMIN - 13]; - break; - } - - switch (sfsi.ssi_signo - SIGRTMIN) { - - case 20: - manager_set_show_status(m, SHOW_STATUS_YES); - break; - - case 21: - manager_set_show_status(m, SHOW_STATUS_NO); - break; - - case 22: - log_set_max_level(LOG_DEBUG); - log_info("Setting log level to debug."); - break; - - case 23: - log_set_max_level(LOG_INFO); - log_info("Setting log level to info."); - break; - - case 24: - if (MANAGER_IS_USER(m)) { - m->exit_code = MANAGER_EXIT; - return 0; - } - - /* This is a nop on init */ - break; - - case 26: - case 29: /* compatibility: used to be mapped to LOG_TARGET_SYSLOG_OR_KMSG */ - log_set_target(LOG_TARGET_JOURNAL_OR_KMSG); - log_notice("Setting log target to journal-or-kmsg."); - break; - - case 27: - log_set_target(LOG_TARGET_CONSOLE); - log_notice("Setting log target to console."); - break; - - case 28: - log_set_target(LOG_TARGET_KMSG); - log_notice("Setting log target to kmsg."); - break; - - default: - log_warning("Got unhandled signal <%s>.", signal_to_string(sfsi.ssi_signo)); - } - } - } - } - - if (sigchld) - manager_dispatch_sigchld(m); + }} return 0; } @@ -2415,11 +2446,10 @@ int manager_loop(Manager *m) { manager_check_finished(m); - /* There might still be some zombies hanging around from - * before we were exec()'ed. Let's reap them. */ - r = manager_dispatch_sigchld(m); + /* There might still be some zombies hanging around from before we were exec()'ed. Let's reap them. */ + r = sd_event_source_set_enabled(m->sigchld_event_source, SD_EVENT_ON); if (r < 0) - return r; + return log_error_errno(r, "Failed to enable SIGCHLD event source: %m"); while (m->exit_code == MANAGER_OK) { usec_t wait_usec; diff --git a/src/core/manager.h b/src/core/manager.h index 216ecea6fd..3af780f866 100644 --- a/src/core/manager.h +++ b/src/core/manager.h @@ -172,6 +172,8 @@ struct Manager { int signal_fd; sd_event_source *signal_event_source; + sd_event_source *sigchld_event_source; + int time_change_fd; sd_event_source *time_change_event_source;