X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fshutdown.c;h=a2f3b539b3023dffbfa589337c9f296eef63aa25;hp=b78c74112a0c1930703e9c88963de4562cd246e6;hb=30923233b34e23ed1b3ffa7317f6219f695fec2f;hpb=3c14d26c4746768f1dc63d4b7ac0278a7abe5da1 diff --git a/src/shutdown.c b/src/shutdown.c index b78c74112..a2f3b539b 100644 --- a/src/shutdown.c +++ b/src/shutdown.c @@ -36,9 +36,8 @@ #include "umount.h" #include "util.h" -#define TIMEOUT_USEC (5 * USEC_PER_SEC) +#define TIMEOUT_USEC (5 * USEC_PER_SEC) #define FINALIZE_ATTEMPTS 50 -#define FINALIZE_CRITICAL_ATTEMPTS 10 static bool ignore_proc(pid_t pid) { if (pid == 1) @@ -69,7 +68,7 @@ static bool is_kernel_thread(pid_t pid) static int killall(int sign) { DIR *dir; struct dirent *d; - unsigned int processes = 0; + unsigned int n_processes = 0; if ((dir = opendir("/proc")) == NULL) return -errno; @@ -87,128 +86,124 @@ static int killall(int sign) { continue; if (kill(pid, sign) == 0) - processes++; + n_processes++; else log_warning("Could not kill %d: %m", pid); } closedir(dir); - return processes; + return n_processes; } -static int send_signal(int sign) { - sigset_t mask, oldmask; +static void wait_for_children(int n_processes, sigset_t *mask) { usec_t until; - int processes; - struct timespec ts; - - assert_se(sigemptyset(&mask) == 0); - assert_se(sigaddset(&mask, SIGCHLD) == 0); - if (sigprocmask(SIG_BLOCK, &mask, &oldmask) != 0) - return -errno; - if (kill(-1, SIGSTOP) < 0) - log_warning("Failed kill(-1, SIGSTOP): %m"); - - processes = killall(sign); - - if (kill(-1, SIGCONT) < 0) - log_warning("Failed kill(-1, SIGCONT): %m"); - - if (processes <= 0) - goto finish; + assert(mask); until = now(CLOCK_MONOTONIC) + TIMEOUT_USEC; for (;;) { - usec_t n = now(CLOCK_MONOTONIC); + struct timespec ts; + int k; + usec_t n; + for (;;) { pid_t pid = waitpid(-1, NULL, WNOHANG); + if (pid == 0) break; - else if (pid < 0 && errno == ECHILD) { - processes = 0; - goto finish; - } - if (--processes == 0) - goto finish; + if (pid < 0 && errno == ECHILD) + return; + + if (n_processes > 0) + if (--n_processes == 0) + return; } + n = now(CLOCK_MONOTONIC); if (n >= until) - goto finish; + return; timespec_store(&ts, until - n); - if (sigtimedwait(&mask, NULL, &ts) != SIGCHLD) - log_warning("Failed: sigtimedwait did not return SIGCHLD: %m"); + + if ((k = sigtimedwait(mask, NULL, &ts)) != SIGCHLD) { + + if (k < 0 && errno != EAGAIN) { + log_error("sigtimedwait() failed: %m"); + return; + } + + if (k >= 0) + log_warning("sigtimedwait() returned unexpected signal."); + } } +} + +static void send_signal(int sign) { + sigset_t mask, oldmask; + int n_processes; + + assert_se(sigemptyset(&mask) == 0); + assert_se(sigaddset(&mask, SIGCHLD) == 0); + assert_se(sigprocmask(SIG_BLOCK, &mask, &oldmask) == 0); + + if (kill(-1, SIGSTOP) < 0 && errno != ESRCH) + log_warning("kill(-1, SIGSTOP) failed: %m"); + + n_processes = killall(sign); + + if (kill(-1, SIGCONT) < 0 && errno != ESRCH) + log_warning("kill(-1, SIGCONT) failed: %m"); + + if (n_processes <= 0) + goto finish; + + wait_for_children(n_processes, &mask); finish: sigprocmask(SIG_SETMASK, &oldmask, NULL); - - return processes; } -static int rescue_send_signal(int sign) { +static void ultimate_send_signal(int sign) { sigset_t mask, oldmask; - usec_t until; - struct timespec ts; int r; - sigemptyset(&mask); - sigaddset(&mask, SIGCHLD); - if (sigprocmask(SIG_BLOCK, &mask, &oldmask) != 0) - return -errno; + assert_se(sigemptyset(&mask) == 0); + assert_se(sigaddset(&mask, SIGCHLD) == 0); + assert_se(sigprocmask(SIG_BLOCK, &mask, &oldmask) == 0); - if (kill(-1, SIGSTOP) < 0) - log_warning("Failed kill(-1, SIGSTOP): %m"); + if (kill(-1, SIGSTOP) < 0 && errno != ESRCH) + log_warning("kill(-1, SIGSTOP) failed: %m"); r = kill(-1, sign); - if (r < 0) - log_warning("Failed kill(-1, %d): %m", sign); + if (r < 0 && errno != ESRCH) + log_warning("kill(-1, %s) failed: %m", signal_to_string(sign)); - if (kill(-1, SIGCONT) < 0) - log_warning("Failed kill(-1, SIGCONT): %m"); + if (kill(-1, SIGCONT) < 0 && errno != ESRCH) + log_warning("kill(-1, SIGCONT) failed: %m"); if (r < 0) goto finish; - until = now(CLOCK_MONOTONIC) + TIMEOUT_USEC; - for (;;) { - usec_t n = now(CLOCK_MONOTONIC); - for (;;) { - pid_t pid = waitpid(-1, NULL, WNOHANG); - if (pid == 0) - break; - else if (pid < 0 && errno == ECHILD) - goto finish; - } - - if (n >= until) - goto finish; - - timespec_store(&ts, until - n); - if (sigtimedwait(&mask, NULL, &ts) != SIGCHLD) - log_warning("Failed: sigtimedwait did not return SIGCHLD: %m"); - } + wait_for_children(0, &mask); finish: sigprocmask(SIG_SETMASK, &oldmask, NULL); - - return r; } - int main(int argc, char *argv[]) { - int cmd, r, retries; - bool need_umount = true, need_swapoff = true, need_loop_detach = true; + int cmd, r; + unsigned retries; + bool need_umount = true, need_swapoff = true, need_loop_detach = true, need_dm_detach = true; + bool killed_everbody = false, in_container; log_parse_environment(); - log_set_target(LOG_TARGET_KMSG); /* syslog will die if not gone yet */ + log_set_target(LOG_TARGET_CONSOLE); /* syslog will die if not gone yet */ log_open(); if (getpid() != 1) { - log_error("Not executed by init (pid-1)."); + log_error("Not executed by init (pid 1)."); r = -EPERM; goto error; } @@ -219,6 +214,8 @@ int main(int argc, char *argv[]) { goto error; } + in_container = detect_container(NULL) > 0; + if (streq(argv[1], "reboot")) cmd = RB_AUTOBOOT; else if (streq(argv[1], "poweroff")) @@ -237,104 +234,128 @@ int main(int argc, char *argv[]) { if (mlockall(MCL_CURRENT|MCL_FUTURE) != 0) log_warning("Cannot lock process memory: %m"); - log_info("Sending SIGTERM to processes"); - r = send_signal(SIGTERM); - if (r < 0) - log_warning("Cannot send SIGTERM to all process: %s", strerror(r)); + log_info("Sending SIGTERM to remaining processes..."); + send_signal(SIGTERM); - log_info("Sending SIGKILL to processes"); - r = send_signal(SIGKILL); - if (r < 0) - log_warning("Cannot send SIGKILL to all process: %s", strerror(r)); + log_info("Sending SIGKILL to remaining processes..."); + send_signal(SIGKILL); + if (in_container) + need_swapoff = false; - /* preventing that we won't block umounts */ - if (chdir("/") != 0) - log_warning("Cannot chdir(\"/\"): %m. Unmounts likely to fail."); + /* Unmount all mountpoints, swaps, and loopback devices */ + for (retries = 0; retries < FINALIZE_ATTEMPTS; retries++) { + bool changed = false; - /* umount all mountpoints, swaps, and loopback devices */ - retries = FINALIZE_ATTEMPTS; - while (need_umount || need_swapoff || need_loop_detach) { if (need_umount) { - log_info("Unmounting filesystems."); - r = umount_all(); + log_info("Unmounting file systems."); + r = umount_all(&changed); if (r == 0) need_umount = false; else if (r > 0) - log_warning("Not all filesystems unmounted, %d left.", r); + log_info("Not all file systems unmounted, %d left.", r); else - log_error("Error unmounting filesystems: %s", strerror(-r)); + log_error("Failed to unmount file systems: %s", strerror(-r)); } if (need_swapoff) { log_info("Disabling swaps."); - r = swapoff_all(); + r = swapoff_all(&changed); if (r == 0) need_swapoff = false; else if (r > 0) - log_warning("Not all swaps are off, %d left.", r); + log_info("Not all swaps are turned off, %d left.", r); else - log_error("Error turning off swaps: %s", strerror(-r)); + log_error("Failed to turn off swaps: %s", strerror(-r)); } if (need_loop_detach) { log_info("Detaching loop devices."); - r = loopback_detach_all(); + r = loopback_detach_all(&changed); if (r == 0) need_loop_detach = false; else if (r > 0) - log_warning("Not all loop devices detached, %d left.", r); + log_info("Not all loop devices detached, %d left.", r); else - log_error("Error detaching loop devices: %s", strerror(-r)); + log_error("Failed to detach loop devices: %s", strerror(-r)); + } + if (need_dm_detach) { + log_info("Detaching DM devices."); + r = dm_detach_all(&changed); + if (r == 0) + need_dm_detach = false; + else if (r > 0) + log_warning("Not all DM devices detached, %d left.", r); + else + log_error("Failed to detach DM devices: %s", strerror(-r)); } - if (need_umount || need_swapoff || need_loop_detach) { - retries--; + if (!need_umount && !need_swapoff && !need_loop_detach && !need_dm_detach) + /* Yay, done */ + break; - if (retries <= FINALIZE_CRITICAL_ATTEMPTS) { - log_warning("Approaching critical level to finalize filesystem and devices, try to kill all processes."); - rescue_send_signal(SIGTERM); - rescue_send_signal(SIGKILL); - } + /* If in this iteration we didn't manage to + * unmount/deactivate anything, we either kill more + * processes, or simply give up */ + if (!changed) { - if (retries > 0) - log_info("Action still required, %d tries left", retries); - else { - log_error("Tried enough but still action required need_umount=%d, need_swapoff=%d, need_loop_detach=%d", need_umount, need_swapoff, need_loop_detach); - r = -EBUSY; - goto error; + if (killed_everbody) { + /* Hmm, we already killed everybody, + * let's just give up */ + log_error("Cannot finalize remaining file systems and devices, giving up."); + break; } + + log_warning("Cannot finalize remaining file systems and devices, trying to kill remaining processes."); + ultimate_send_signal(SIGTERM); + ultimate_send_signal(SIGKILL); + killed_everbody = true; } + + log_debug("Couldn't finalize remaining file systems and devices after %u retries, trying again.", retries+1); + } + + if (retries >= FINALIZE_ATTEMPTS) + log_error("Too many iterations, giving up."); + + execute_directory(SYSTEM_SHUTDOWN_PATH, NULL, NULL); + + /* If we are in a container, just exit, this will kill our + * container for good. */ + if (in_container) { + log_error("Exiting container."); + exit(0); } sync(); if (cmd == LINUX_REBOOT_CMD_KEXEC) { - /* we cheat and exec kexec to avoid doing all its work */ + /* We cheat and exec kexec to avoid doing all its work */ pid_t pid = fork(); - if (pid < 0) { - log_error("Could not fork: %m. Falling back to reboot."); - cmd = RB_AUTOBOOT; - } else if (pid > 0) { - waitpid(pid, NULL, 0); - log_warning("Failed %s -e -x -f. Falling back to reboot", KEXEC_BINARY_PATH); - cmd = RB_AUTOBOOT; + + if (pid < 0) + log_error("Could not fork: %m. Falling back to normal reboot."); + else if (pid > 0) { + wait_for_terminate_and_warn("kexec", pid); + log_warning("kexec failed. Falling back to normal reboot."); } else { - const char *args[5] = {KEXEC_BINARY_PATH, "-e", "-f", "-x", NULL}; + /* Child */ + const char *args[3] = { "/sbin/kexec", "-e", NULL }; execv(args[0], (char * const *) args); return EXIT_FAILURE; } + + cmd = RB_AUTOBOOT; } reboot(cmd); - r = errno; + log_error("Failed to invoke reboot(): %m"); + r = -errno; error: - sync(); - if (r < 0) - r = -r; - log_error("Critical error while doing system shutdown: %s", strerror(r)); + log_error("Critical error while doing system shutdown: %s", strerror(-r)); + freeze(); return EXIT_FAILURE; }