journald: port to sd-event and enable watchdog support

12 files changed, 285 insertions, 329 deletions

diff --git a/Makefile.am b/Makefile.am
index 9e4b1363ce..25bbcab888 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -2952,7 +2952,9 @@ systemd_journald_SOURCES = \
 	src/journal/journald-server.h
 
 systemd_journald_LDADD = \
-	libsystemd-journal-core.la
+	libsystemd-journal-core.la \
+	libsystemd-bus-internal.la \
+	libsystemd-shared.la
 
 systemd_cat_SOURCES = \
 	src/journal/cat.c
diff --git a/TODO b/TODO
index d909ab9d87..dae1056f28 100644
--- a/TODO
+++ b/TODO
@@ -137,6 +137,7 @@ Features:
     but do not return anything up to the event loop caller. Instead
     add parameter to sd_event_request_quit() to take retval. This way
     errors rippling upwards are the option, not the default
+  - event sources should not be able to keep the sd_event around unconditionally
 
 * in the final killing spree, detect processes from the root directory, and
   complain loudly if they have argv[0][0] == '@' set.
@@ -310,7 +311,6 @@ Features:
     boot, and causes the journal to be moved back to /run on shutdown,
     so that we don't keep /var busy. This needs to happen synchronously,
     hence doing this via signals is not going to work.
-  - port to sd-event, enable watchdog from event loop
 
 * document:
   - document that deps in [Unit] sections ignore Alias= fileds in
diff --git a/src/journal/journald-kmsg.c b/src/journal/journald-kmsg.c
index af49d8578a..bc42548cd1 100644
--- a/src/journal/journald-kmsg.c
+++ b/src/journal/journald-kmsg.c
@@ -320,7 +320,7 @@ finish:
         free(pid);
 }
 
-int server_read_dev_kmsg(Server *s) {
+static int server_read_dev_kmsg(Server *s) {
         char buffer[8192+1]; /* the kernel-side limit per record is 8K currently */
         ssize_t l;
 
@@ -335,7 +335,7 @@ int server_read_dev_kmsg(Server *s) {
                  * return EINVAL when we try. So handle this cleanly,
                  * but don' try to ever read from it again. */
                 if (errno == EINVAL) {
-                        epoll_ctl(s->epoll_fd, EPOLL_CTL_DEL, s->dev_kmsg_fd, NULL);
+                        s->dev_kmsg_event_source = sd_event_source_unref(s->dev_kmsg_event_source);
                         return 0;
                 }
 
@@ -375,8 +375,24 @@ int server_flush_dev_kmsg(Server *s) {
         return 0;
 }
 
+static int dispatch_dev_kmsg(sd_event_source *es, int fd, uint32_t revents, void *userdata) {
+        Server *s = userdata;
+
+        assert(es);
+        assert(fd == s->dev_kmsg_fd);
+        assert(s);
+
+        if (revents & EPOLLERR)
+                log_warning("/dev/kmsg buffer overrun, some messages lost.");
+
+        if (!(revents & EPOLLIN))
+                log_error("Got invalid event from epoll for /dev/kmsg: %"PRIx32, revents);
+
+        return server_read_dev_kmsg(s);
+}
+
 int server_open_dev_kmsg(Server *s) {
-        struct epoll_event ev;
+        int r;
 
         assert(s);
 
@@ -386,17 +402,21 @@ int server_open_dev_kmsg(Server *s) {
                 return 0;
         }
 
-        zero(ev);
-        ev.events = EPOLLIN;
-        ev.data.fd = s->dev_kmsg_fd;
-        if (epoll_ctl(s->epoll_fd, EPOLL_CTL_ADD, s->dev_kmsg_fd, &ev) < 0) {
+        r = sd_event_add_io(s->event, s->dev_kmsg_fd, EPOLLIN, dispatch_dev_kmsg, s, &s->dev_kmsg_event_source);
+        if (r < 0) {
 
                 /* This will fail with EPERM on older kernels where
                  * /dev/kmsg is not readable. */
-                if (errno == EPERM)
+                if (r == -EPERM)
                         return 0;
 
-                log_error("Failed to add /dev/kmsg fd to epoll object: %m");
+                log_error("Failed to add /dev/kmsg fd to event loop: %s", strerror(-r));
+                return -errno;
+        }
+
+        r = sd_event_source_set_priority(s->dev_kmsg_event_source, SD_EVENT_PRIORITY_IMPORTANT+10);
+        if (r < 0) {
+                log_error("Failed to adjust priority of kmsg event source: %s", strerror(-r));
                 return -errno;
         }
 
diff --git a/src/journal/journald-kmsg.h b/src/journal/journald-kmsg.h
index f287161329..f60f605572 100644
--- a/src/journal/journald-kmsg.h
+++ b/src/journal/journald-kmsg.h
@@ -24,7 +24,6 @@
 #include "journald-server.h"
 
 int server_open_dev_kmsg(Server *s);
-int server_read_dev_kmsg(Server *s);
 int server_flush_dev_kmsg(Server *s);
 
 void server_forward_kmsg(Server *s, int priority, const char *identifier, const char *message, struct ucred *ucred);
diff --git a/src/journal/journald-native.c b/src/journal/journald-native.c
index 2c91cba16d..5e19fa3f55 100644
--- a/src/journal/journald-native.c
+++ b/src/journal/journald-native.c
@@ -369,7 +369,6 @@ void server_process_native_file(
 int server_open_native_socket(Server*s) {
         union sockaddr_union sa;
         int one, r;
-        struct epoll_event ev;
 
         assert(s);
 
@@ -420,12 +419,10 @@ int server_open_native_socket(Server*s) {
                 return -errno;
         }
 
-        zero(ev);
-        ev.events = EPOLLIN;
-        ev.data.fd = s->native_fd;
-        if (epoll_ctl(s->epoll_fd, EPOLL_CTL_ADD, s->native_fd, &ev) < 0) {
-                log_error("Failed to add native server fd to epoll object: %m");
-                return -errno;
+        r = sd_event_add_io(s->event, s->native_fd, EPOLLIN, process_datagram, s, &s->native_event_source);
+        if (r < 0) {
+                log_error("Failed to add native server fd to event loop: %s", strerror(-r));
+                return r;
         }
 
         return 0;
diff --git a/src/journal/journald-server.c b/src/journal/journald-server.c
index fc8115c31c..dd14493db5 100644
--- a/src/journal/journald-server.c
+++ b/src/journal/journald-server.c
@@ -333,7 +333,6 @@ void server_rotate(Server *s) {
 }
 
 void server_sync(Server *s) {
-        static const struct itimerspec sync_timer_disable = {};
         JournalFile *f;
         void *k;
         Iterator i;
@@ -351,9 +350,11 @@ void server_sync(Server *s) {
                         log_error("Failed to sync user journal: %s", strerror(-r));
         }
 
-        r = timerfd_settime(s->sync_timer_fd, 0, &sync_timer_disable, NULL);
-        if (r < 0)
-                log_error("Failed to disable max timer: %m");
+        if (s->sync_event_source) {
+                r = sd_event_source_set_enabled(s->sync_event_source, SD_EVENT_OFF);
+                if (r < 0)
+                        log_error("Failed to disable sync timer source: %s", strerror(-r));
+        }
 
         s->sync_scheduled = false;
 }
@@ -1067,235 +1068,157 @@ finish:
         return r;
 }
 
-int process_event(Server *s, struct epoll_event *ev) {
+int process_datagram(sd_event_source *es, int fd, uint32_t revents, void *userdata) {
+        Server *s = userdata;
+
         assert(s);
-        assert(ev);
+        assert(fd == s->native_fd || fd == s->syslog_fd);
+
+        if (revents != EPOLLIN) {
+                log_error("Got invalid event from epoll for datagram fd: %"PRIx32, revents);
+                return -EIO;
+        }
+
+        for (;;) {
+                struct ucred *ucred = NULL;
+                struct timeval *tv = NULL;
+                struct cmsghdr *cmsg;
+                char *label = NULL;
+                size_t label_len = 0;
+                struct iovec iovec;
+
+                union {
+                        struct cmsghdr cmsghdr;
+
+                        /* We use NAME_MAX space for the
+                         * SELinux label here. The kernel
+                         * currently enforces no limit, but
+                         * according to suggestions from the
+                         * SELinux people this will change and
+                         * it will probably be identical to
+                         * NAME_MAX. For now we use that, but
+                         * this should be updated one day when
+                         * the final limit is known.*/
+                        uint8_t buf[CMSG_SPACE(sizeof(struct ucred)) +
+                                    CMSG_SPACE(sizeof(struct timeval)) +
+                                    CMSG_SPACE(sizeof(int)) + /* fd */
+                                    CMSG_SPACE(NAME_MAX)]; /* selinux label */
+                } control = {};
+                struct msghdr msghdr = {
+                        .msg_iov = &iovec,
+                        .msg_iovlen = 1,
+                        .msg_control = &control,
+                        .msg_controllen = sizeof(control),
+                };
 
-        if (ev->data.fd == s->signal_fd) {
-                struct signalfd_siginfo sfsi;
                 ssize_t n;
+                int v;
+                int *fds = NULL;
+                unsigned n_fds = 0;
 
-                if (ev->events != EPOLLIN) {
-                        log_error("Got invalid event from epoll for %s: %"PRIx32,
-                                  "signal fd", ev->events);
-                        return -EIO;
+                if (ioctl(fd, SIOCINQ, &v) < 0) {
+                        log_error("SIOCINQ failed: %m");
+                        return -errno;
                 }
 
-                n = read(s->signal_fd, &sfsi, sizeof(sfsi));
-                if (n != sizeof(sfsi)) {
+                if (!GREEDY_REALLOC(s->buffer, s->buffer_size, LINE_MAX + (size_t) v))
+                        return log_oom();
 
-                        if (n >= 0)
-                                return -EIO;
+                iovec.iov_base = s->buffer;
+                iovec.iov_len = s->buffer_size;
 
+                n = recvmsg(fd, &msghdr, MSG_DONTWAIT|MSG_CMSG_CLOEXEC);
+                if (n < 0) {
                         if (errno == EINTR || errno == EAGAIN)
-                                return 1;
+                                return 0;
 
+                        log_error("recvmsg() failed: %m");
                         return -errno;
                 }
 
-                if (sfsi.ssi_signo == SIGUSR1) {
-                        log_info("Received request to flush runtime journal from PID %"PRIu32,
-                                 sfsi.ssi_pid);
-                        touch("/run/systemd/journal/flushed");
-                        server_flush_to_var(s);
-                        server_sync(s);
-                        return 1;
-                }
-
-                if (sfsi.ssi_signo == SIGUSR2) {
-                        log_info("Received request to rotate journal from PID %"PRIu32,
-                                 sfsi.ssi_pid);
-                        server_rotate(s);
-                        server_vacuum(s);
-                        return 1;
+                for (cmsg = CMSG_FIRSTHDR(&msghdr); cmsg; cmsg = CMSG_NXTHDR(&msghdr, cmsg)) {
+
+                        if (cmsg->cmsg_level == SOL_SOCKET &&
+                            cmsg->cmsg_type == SCM_CREDENTIALS &&
+                            cmsg->cmsg_len == CMSG_LEN(sizeof(struct ucred)))
+                                ucred = (struct ucred*) CMSG_DATA(cmsg);
+                        else if (cmsg->cmsg_level == SOL_SOCKET &&
+                                 cmsg->cmsg_type == SCM_SECURITY) {
+                                label = (char*) CMSG_DATA(cmsg);
+                                label_len = cmsg->cmsg_len - CMSG_LEN(0);
+                        } else if (cmsg->cmsg_level == SOL_SOCKET &&
+                                   cmsg->cmsg_type == SO_TIMESTAMP &&
+                                   cmsg->cmsg_len == CMSG_LEN(sizeof(struct timeval)))
+                                tv = (struct timeval*) CMSG_DATA(cmsg);
+                        else if (cmsg->cmsg_level == SOL_SOCKET &&
+                                 cmsg->cmsg_type == SCM_RIGHTS) {
+                                fds = (int*) CMSG_DATA(cmsg);
+                                n_fds = (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int);
+                        }
                 }
 
-                log_info("Received SIG%s", signal_to_string(sfsi.ssi_signo));
-
-                return 0;
+                if (fd == s->syslog_fd) {
+                        if (n > 0 && n_fds == 0) {
+                                s->buffer[n] = 0;
+                                server_process_syslog_message(s, strstrip(s->buffer), ucred, tv, label, label_len);
+                        } else if (n_fds > 0)
+                                log_warning("Got file descriptors via syslog socket. Ignoring.");
 
-        } else if (ev->data.fd == s->sync_timer_fd) {
-                int r;
-                uint64_t t;
-
-                log_debug("Got sync request from epoll.");
-
-                r = read(ev->data.fd, (void *)&t, sizeof(t));
-                if (r < 0)
-                        return 0;
-
-                server_sync(s);
-                return 1;
-
-        } else if (ev->data.fd == s->dev_kmsg_fd) {
-                int r;
-
-                if (ev->events & EPOLLERR)
-                        log_warning("/dev/kmsg buffer overrun, some messages lost.");
-
-                if (!(ev->events & EPOLLIN)) {
-                        log_error("Got invalid event from epoll for %s: %"PRIx32,
-                                  "/dev/kmsg", ev->events);
-                        return -EIO;
-                }
-
-                r = server_read_dev_kmsg(s);
-                if (r < 0)
-                        return r;
-
-                return 1;
-
-        } else if (ev->data.fd == s->native_fd ||
-                   ev->data.fd == s->syslog_fd) {
-
-                if (ev->events != EPOLLIN) {
-                        log_error("Got invalid event from epoll for %s: %"PRIx32,
-                                  ev->data.fd == s->native_fd ? "native fd" : "syslog fd",
-                                  ev->events);
-                        return -EIO;
+                } else {
+                        if (n > 0 && n_fds == 0)
+                                server_process_native_message(s, s->buffer, n, ucred, tv, label, label_len);
+                        else if (n == 0 && n_fds == 1)
+                                server_process_native_file(s, fds[0], ucred, tv, label, label_len);
+                        else if (n_fds > 0)
+                                log_warning("Got too many file descriptors via native socket. Ignoring.");
                 }
 
-                for (;;) {
-                        struct ucred *ucred = NULL;
-                        struct timeval *tv = NULL;
-                        struct cmsghdr *cmsg;
-                        char *label = NULL;
-                        size_t label_len = 0;
-
-                        struct iovec iovec;
-                        union {
-                                struct cmsghdr cmsghdr;
-
-                                /* We use NAME_MAX space for the
-                                 * SELinux label here. The kernel
-                                 * currently enforces no limit, but
-                                 * according to suggestions from the
-                                 * SELinux people this will change and
-                                 * it will probably be identical to
-                                 * NAME_MAX. For now we use that, but
-                                 * this should be updated one day when
-                                 * the final limit is known.*/
-                                uint8_t buf[CMSG_SPACE(sizeof(struct ucred)) +
-                                            CMSG_SPACE(sizeof(struct timeval)) +
-                                            CMSG_SPACE(sizeof(int)) + /* fd */
-                                            CMSG_SPACE(NAME_MAX)]; /* selinux label */
-                        } control = {};
-                        struct msghdr msghdr = {
-                                .msg_iov = &iovec,
-                                .msg_iovlen = 1,
-                                .msg_control = &control,
-                                .msg_controllen = sizeof(control),
-                        };
-
-                        ssize_t n;
-                        int v;
-                        int *fds = NULL;
-                        unsigned n_fds = 0;
-
-                        if (ioctl(ev->data.fd, SIOCINQ, &v) < 0) {
-                                log_error("SIOCINQ failed: %m");
-                                return -errno;
-                        }
-
-                        if (!GREEDY_REALLOC(s->buffer, s->buffer_size, LINE_MAX + (size_t) v))
-                                return log_oom();
-
-                        iovec.iov_base = s->buffer;
-                        iovec.iov_len = s->buffer_size;
-
-                        n = recvmsg(ev->data.fd, &msghdr, MSG_DONTWAIT|MSG_CMSG_CLOEXEC);
-                        if (n < 0) {
-                                if (errno == EINTR || errno == EAGAIN)
-                                        return 1;
-
-                                log_error("recvmsg() failed: %m");
-                                return -errno;
-                        }
-
-                        for (cmsg = CMSG_FIRSTHDR(&msghdr); cmsg; cmsg = CMSG_NXTHDR(&msghdr, cmsg)) {
-
-                                if (cmsg->cmsg_level == SOL_SOCKET &&
-                                    cmsg->cmsg_type == SCM_CREDENTIALS &&
-                                    cmsg->cmsg_len == CMSG_LEN(sizeof(struct ucred)))
-                                        ucred = (struct ucred*) CMSG_DATA(cmsg);
-                                else if (cmsg->cmsg_level == SOL_SOCKET &&
-                                         cmsg->cmsg_type == SCM_SECURITY) {
-                                        label = (char*) CMSG_DATA(cmsg);
-                                        label_len = cmsg->cmsg_len - CMSG_LEN(0);
-                                } else if (cmsg->cmsg_level == SOL_SOCKET &&
-                                           cmsg->cmsg_type == SO_TIMESTAMP &&
-                                           cmsg->cmsg_len == CMSG_LEN(sizeof(struct timeval)))
-                                        tv = (struct timeval*) CMSG_DATA(cmsg);
-                                else if (cmsg->cmsg_level == SOL_SOCKET &&
-                                         cmsg->cmsg_type == SCM_RIGHTS) {
-                                        fds = (int*) CMSG_DATA(cmsg);
-                                        n_fds = (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int);
-                                }
-                        }
+                close_many(fds, n_fds);
+        }
 
-                        if (ev->data.fd == s->syslog_fd) {
-                                if (n > 0 && n_fds == 0) {
-                                        s->buffer[n] = 0;
-                                        server_process_syslog_message(s, strstrip(s->buffer), ucred, tv, label, label_len);
-                                } else if (n_fds > 0)
-                                        log_warning("Got file descriptors via syslog socket. Ignoring.");
+        return 0;
+}
 
-                        } else {
-                                if (n > 0 && n_fds == 0)
-                                        server_process_native_message(s, s->buffer, n, ucred, tv, label, label_len);
-                                else if (n == 0 && n_fds == 1)
-                                        server_process_native_file(s, fds[0], ucred, tv, label, label_len);
-                                else if (n_fds > 0)
-                                        log_warning("Got too many file descriptors via native socket. Ignoring.");
-                        }
+static int dispatch_sigusr1(sd_event_source *es, const struct signalfd_siginfo *si, void *userdata) {
+        Server *s = userdata;
 
-                        close_many(fds, n_fds);
-                }
+        assert(s);
 
-                return 1;
+        log_info("Received request to flush runtime journal from PID %"PRIu32, si->ssi_pid);
 
-        } else if (ev->data.fd == s->stdout_fd) {
+        touch("/run/systemd/journal/flushed");
+        server_flush_to_var(s);
+        server_sync(s);
 
-                if (ev->events != EPOLLIN) {
-                        log_error("Got invalid event from epoll for %s: %"PRIx32,
-                                  "stdout fd", ev->events);
-                        return -EIO;
-                }
+        return 0;
+}
 
-                stdout_stream_new(s);
-                return 1;
+static int dispatch_sigusr2(sd_event_source *es, const struct signalfd_siginfo *si, void *userdata) {
+        Server *s = userdata;
 
-        } else {
-                StdoutStream *stream;
+        assert(s);
 
-                if ((ev->events|EPOLLIN|EPOLLHUP) != (EPOLLIN|EPOLLHUP)) {
-                        log_error("Got invalid event from epoll for %s: %"PRIx32,
-                                  "stdout stream", ev->events);
-                        return -EIO;
-                }
+        log_info("Received request to rotate journal from PID %"PRIu32, si->ssi_pid);
+        server_rotate(s);
+        server_vacuum(s);
 
-                /* If it is none of the well-known fds, it must be an
-                 * stdout stream fd. Note that this is a bit ugly here
-                 * (since we rely that none of the well-known fds
-                 * could be interpreted as pointer), but nonetheless
-                 * safe, since the well-known fds would never get an
-                 * fd > 4096, i.e. beyond the first memory page */
+        return 0;
+}
 
-                stream = ev->data.ptr;
+static int dispatch_sigterm(sd_event_source *es, const struct signalfd_siginfo *si, void *userdata) {
+        Server *s = userdata;
 
-                if (stdout_stream_process(stream) <= 0)
-                        stdout_stream_free(stream);
+        assert(s);
 
-                return 1;
-        }
+        log_info("Received SIG%s", signal_to_string(si->ssi_signo));
 
-        log_error("Unknown event.");
+        sd_event_request_quit(s->event);
         return 0;
 }
 
-static int open_signalfd(Server *s) {
+static int setup_signals(Server *s) {
         sigset_t mask;
-        struct epoll_event ev;
+        int r;
 
         assert(s);
 
@@ -1303,20 +1226,21 @@ static int open_signalfd(Server *s) {
         sigset_add_many(&mask, SIGINT, SIGTERM, SIGUSR1, SIGUSR2, -1);
         assert_se(sigprocmask(SIG_SETMASK, &mask, NULL) == 0);
 
-        s->signal_fd = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
-        if (s->signal_fd < 0) {
-                log_error("signalfd(): %m");
-                return -errno;
-        }
+        r = sd_event_add_signal(s->event, SIGUSR1, dispatch_sigusr1, s, &s->sigusr1_event_source);
+        if (r < 0)
+                return r;
+
+        r = sd_event_add_signal(s->event, SIGUSR2, dispatch_sigusr2, s, &s->sigusr2_event_source);
+        if (r < 0)
+                return r;
 
-        zero(ev);
-        ev.events = EPOLLIN;
-        ev.data.fd = s->signal_fd;
+        r = sd_event_add_signal(s->event, SIGTERM, dispatch_sigterm, s, &s->sigterm_event_source);
+        if (r < 0)
+                return r;
 
-        if (epoll_ctl(s->epoll_fd, EPOLL_CTL_ADD, s->signal_fd, &ev) < 0) {
-                log_error("epoll_ctl(): %m");
-                return -errno;
-        }
+        r = sd_event_add_signal(s->event, SIGINT, dispatch_sigterm, s, &s->sigint_event_source);
+        if (r < 0)
+                return r;
 
         return 0;
 }
@@ -1389,26 +1313,12 @@ static int server_parse_config_file(Server *s) {
         return r;
 }
 
-static int server_open_sync_timer(Server *s) {
-        int r;
-        struct epoll_event ev;
+static int server_dispatch_sync(sd_event_source *es, usec_t t, void *userdata) {
+        Server *s = userdata;
 
         assert(s);
 
-        s->sync_timer_fd = timerfd_create(CLOCK_MONOTONIC, TFD_CLOEXEC);
-        if (s->sync_timer_fd < 0)
-                return -errno;
-
-        zero(ev);
-        ev.events = EPOLLIN;
-        ev.data.fd = s->sync_timer_fd;
-
-        r = epoll_ctl(s->epoll_fd, EPOLL_CTL_ADD, s->sync_timer_fd, &ev);
-        if (r < 0) {
-                log_error("Failed to add idle timer fd to epoll object: %m");
-                return -errno;
-        }
-
+        server_sync(s);
         return 0;
 }
 
@@ -1426,17 +1336,33 @@ int server_schedule_sync(Server *s, int priority) {
         if (s->sync_scheduled)
                 return 0;
 
-        if (s->sync_interval_usec) {
-                struct itimerspec sync_timer_enable = {};
+        if (s->sync_interval_usec > 0) {
+                usec_t when;
 
-                timespec_store(&sync_timer_enable.it_value, s->sync_interval_usec);
+                r = sd_event_get_now_monotonic(s->event, &when);
+                if (r < 0)
+                        return r;
 
-                r = timerfd_settime(s->sync_timer_fd, 0, &sync_timer_enable, NULL);
+                when += s->sync_interval_usec;
+
+                if (!s->sync_event_source) {
+                        r = sd_event_add_monotonic(s->event, when, 0, server_dispatch_sync, s, &s->sync_event_source);
+                        if (r < 0)
+                                return r;
+
+                        r = sd_event_source_set_priority(s->sync_event_source, SD_EVENT_PRIORITY_IMPORTANT);
+                } else {
+                        r = sd_event_source_set_time(s->sync_event_source, when);
+                        if (r < 0)
+                                return r;
+
+                        r = sd_event_source_set_enabled(s->sync_event_source, SD_EVENT_ONESHOT);
+                }
                 if (r < 0)
-                        return -errno;
-        }
+                        return r;
 
-        s->sync_scheduled = true;
+                s->sync_scheduled = true;
+        }
 
         return 0;
 }
@@ -1447,8 +1373,7 @@ int server_init(Server *s) {
         assert(s);
 
         zero(*s);
-        s->sync_timer_fd = s->syslog_fd = s->native_fd = s->stdout_fd =
-                s->signal_fd = s->epoll_fd = s->dev_kmsg_fd = -1;
+        s->syslog_fd = s->native_fd = s->stdout_fd = s->dev_kmsg_fd = -1;
         s->compress = true;
         s->seal = true;
 
@@ -1487,12 +1412,14 @@ int server_init(Server *s) {
         if (!s->mmap)
                 return log_oom();
 
-        s->epoll_fd = epoll_create1(EPOLL_CLOEXEC);
-        if (s->epoll_fd < 0) {
-                log_error("Failed to create epoll object: %m");
-                return -errno;
+        r = sd_event_default(&s->event);
+        if (r < 0) {
+                log_error("Failed to create event loop: %s", strerror(-r));
+                return r;
         }
 
+        sd_event_set_watchdog(s->event, true);
+
         n = sd_listen_fds(true);
         if (n < 0) {
                 log_error("Failed to read listening file descriptors from environment: %s", strerror(-n));
@@ -1554,11 +1481,7 @@ int server_init(Server *s) {
         if (r < 0)
                 return r;
 
-        r = server_open_sync_timer(s);
-        if (r < 0)
-                return r;
-
-        r = open_signalfd(s);
+        r = setup_signals(s);
         if (r < 0)
                 return r;
 
@@ -1566,8 +1489,7 @@ int server_init(Server *s) {
         if (!s->udev)
                 return -ENOMEM;
 
-        s->rate_limit = journal_rate_limit_new(s->rate_limit_interval,
-                                               s->rate_limit_burst);
+        s->rate_limit = journal_rate_limit_new(s->rate_limit_interval, s->rate_limit_burst);
         if (!s->rate_limit)
                 return -ENOMEM;
 
@@ -1612,11 +1534,16 @@ void server_done(Server *s) {
 
         hashmap_free(s->user_journals);
 
-        if (s->epoll_fd >= 0)
-                close_nointr_nofail(s->epoll_fd);
-
-        if (s->signal_fd >= 0)
-                close_nointr_nofail(s->signal_fd);
+        sd_event_source_unref(s->syslog_event_source);
+        sd_event_source_unref(s->native_event_source);
+        sd_event_source_unref(s->stdout_event_source);
+        sd_event_source_unref(s->dev_kmsg_event_source);
+        sd_event_source_unref(s->sync_event_source);
+        sd_event_source_unref(s->sigusr1_event_source);
+        sd_event_source_unref(s->sigusr2_event_source);
+        sd_event_source_unref(s->sigterm_event_source);
+        sd_event_source_unref(s->sigint_event_source);
+        sd_event_unref(s->event);
 
         if (s->syslog_fd >= 0)
                 close_nointr_nofail(s->syslog_fd);
@@ -1630,9 +1557,6 @@ void server_done(Server *s) {
         if (s->dev_kmsg_fd >= 0)
                 close_nointr_nofail(s->dev_kmsg_fd);
 
-        if (s->sync_timer_fd >= 0)
-                close_nointr_nofail(s->sync_timer_fd);
-
         if (s->rate_limit)
                 journal_rate_limit_free(s->rate_limit);
 
diff --git a/src/journal/journald-server.h b/src/journal/journald-server.h
index db577b8913..2c3e2c239d 100644
--- a/src/journal/journald-server.h
+++ b/src/journal/journald-server.h
@@ -27,6 +27,7 @@
 #include <sys/types.h>
 #include <sys/socket.h>
 
+#include "sd-event.h"
 #include "journal-file.h"
 #include "hashmap.h"
 #include "util.h"
@@ -54,13 +55,23 @@ typedef enum SplitMode {
 typedef struct StdoutStream StdoutStream;
 
 typedef struct Server {
-        int epoll_fd;
-        int signal_fd;
         int syslog_fd;
         int native_fd;
         int stdout_fd;
         int dev_kmsg_fd;
 
+        sd_event *event;
+
+        sd_event_source *syslog_event_source;
+        sd_event_source *native_event_source;
+        sd_event_source *stdout_event_source;
+        sd_event_source *dev_kmsg_event_source;
+        sd_event_source *sync_event_source;
+        sd_event_source *sigusr1_event_source;
+        sd_event_source *sigusr2_event_source;
+        sd_event_source *sigterm_event_source;
+        sd_event_source *sigint_event_source;
+
         JournalFile *runtime_journal;
         JournalFile *system_journal;
         Hashmap *user_journals;
@@ -118,7 +129,6 @@ typedef struct Server {
 
         struct udev *udev;
 
-        int sync_timer_fd;
         bool sync_scheduled;
 } Server;
 
@@ -152,5 +162,5 @@ void server_vacuum(Server *s);
 void server_rotate(Server *s);
 int server_schedule_sync(Server *s, int priority);
 int server_flush_to_var(Server *s);
-int process_event(Server *s, struct epoll_event *ev);
 void server_maybe_append_tags(Server *s);
+int process_datagram(sd_event_source *es, int fd, uint32_t revents, void *userdata);
diff --git a/src/journal/journald-stream.c b/src/journal/journald-stream.c
index 5c15a56bac..e887f01a49 100644
--- a/src/journal/journald-stream.c
+++ b/src/journal/journald-stream.c
@@ -22,12 +22,12 @@
 #include <fcntl.h>
 #include <unistd.h>
 #include <stddef.h>
-#include <sys/epoll.h>
 
 #ifdef HAVE_SELINUX
 #include <selinux/selinux.h>
 #endif
 
+#include "sd-event.h"
 #include "socket-util.h"
 #include "selinux-util.h"
 #include "journald-server.h"
@@ -71,6 +71,8 @@ struct StdoutStream {
         char buffer[LINE_MAX+1];
         size_t length;
 
+        sd_event_source *event_source;
+
         LIST_FIELDS(StdoutStream, stdout_stream);
 };
 
@@ -282,12 +284,18 @@ static int stdout_stream_scan(StdoutStream *s, bool force_flush) {
         return 0;
 }
 
-int stdout_stream_process(StdoutStream *s) {
+static int stdout_stream_process(sd_event_source *es, int fd, uint32_t revents, void *userdata) {
+        StdoutStream *s = userdata;
         ssize_t l;
         int r;
 
         assert(s);
 
+        if ((revents|EPOLLIN|EPOLLHUP) != (EPOLLIN|EPOLLHUP)) {
+                log_error("Got invalid event from epoll for stdout stream: %"PRIx32, revents);
+                return -EIO;
+        }
+
         l = read(s->fd, s->buffer+s->length, sizeof(s->buffer)-1-s->length);
         if (l < 0) {
 
@@ -295,13 +303,13 @@ int stdout_stream_process(StdoutStream *s) {
                         return 0;
 
                 log_warning("Failed to read from stream: %m");
-                return -errno;
+                goto fail;
         }
 
         if (l == 0) {
                 r = stdout_stream_scan(s, true);
                 if (r < 0)
-                        return r;
+                        goto fail;
 
                 return 0;
         }
@@ -309,10 +317,13 @@ int stdout_stream_process(StdoutStream *s) {
         s->length += l;
         r = stdout_stream_scan(s, false);
         if (r < 0)
-                return r;
+                goto fail;
 
         return 1;
 
+fail:
+        stdout_stream_free(s);
+        return 0;
 }
 
 void stdout_stream_free(StdoutStream *s) {
@@ -324,12 +335,11 @@ void stdout_stream_free(StdoutStream *s) {
                 LIST_REMOVE(stdout_stream, s->server->stdout_streams, s);
         }
 
-        if (s->fd >= 0) {
-                if (s->server)
-                        epoll_ctl(s->server->epoll_fd, EPOLL_CTL_DEL, s->fd, NULL);
+        if (s->event_source)
+                s->event_source = sd_event_source_unref(s->event_source);
 
+        if (s->fd >= 0)
                 close_nointr_nofail(s->fd);
-        }
 
 #ifdef HAVE_SELINUX
         if (s->security_context)
@@ -341,14 +351,19 @@ void stdout_stream_free(StdoutStream *s) {
         free(s);
 }
 
-int stdout_stream_new(Server *s) {
+static int stdout_stream_new(sd_event_source *es, int listen_fd, uint32_t revents, void *userdata) {
+        Server *s = userdata;
         StdoutStream *stream;
         int fd, r;
         socklen_t len;
-        struct epoll_event ev;
 
         assert(s);
 
+        if (revents != EPOLLIN) {
+                log_error("Got invalid event from epoll for stdout server fd: %"PRIx32, revents);
+                return -EIO;
+        }
+
         fd = accept4(s->stdout_fd, NULL, NULL, SOCK_NONBLOCK|SOCK_CLOEXEC);
         if (fd < 0) {
                 if (errno == EAGAIN)
@@ -392,12 +407,15 @@ int stdout_stream_new(Server *s) {
                 goto fail;
         }
 
-        zero(ev);
-        ev.data.ptr = stream;
-        ev.events = EPOLLIN;
-        if (epoll_ctl(s->epoll_fd, EPOLL_CTL_ADD, fd, &ev) < 0) {
-                log_error("Failed to add stream to event loop: %m");
-                r = -errno;
+        r = sd_event_add_io(s->event, fd, EPOLLIN, stdout_stream_process, stream, &stream->event_source);
+        if (r < 0) {
+                log_error("Failed to add stream to event loop: %s", strerror(-r));
+                goto fail;
+        }
+
+        r = sd_event_source_set_priority(stream->event_source, SD_EVENT_PRIORITY_NORMAL+5);
+        if (r < 0) {
+                log_error("Failed to adjust stdout event source priority: %s", strerror(-r));
                 goto fail;
         }
 
@@ -414,7 +432,6 @@ fail:
 
 int server_open_stdout_socket(Server *s) {
         int r;
-        struct epoll_event ev = { .events = EPOLLIN };
 
         assert(s);
 
@@ -447,10 +464,16 @@ int server_open_stdout_socket(Server *s) {
         } else
                 fd_nonblock(s->stdout_fd, 1);
 
-        ev.data.fd = s->stdout_fd;
-        if (epoll_ctl(s->epoll_fd, EPOLL_CTL_ADD, s->stdout_fd, &ev) < 0) {
-                log_error("Failed to add stdout server fd to epoll object: %m");
-                return -errno;
+        r = sd_event_add_io(s->event, s->stdout_fd, EPOLLIN, stdout_stream_new, s, &s->stdout_event_source);
+        if (r < 0) {
+                log_error("Failed to add stdout server fd to event source: %s", strerror(-r));
+                return r;
+        }
+
+        r = sd_event_source_set_priority(s->stdout_event_source, SD_EVENT_PRIORITY_NORMAL+10);
+        if (r < 0) {
+                log_error("Failed to adjust priority of stdout server event source: %s", strerror(-r));
+                return r;
         }
 
         return 0;
diff --git a/src/journal/journald-stream.h b/src/journal/journald-stream.h
index dfb6267bf6..8cad012967 100644
--- a/src/journal/journald-stream.h
+++ b/src/journal/journald-stream.h
@@ -25,6 +25,4 @@
 
 int server_open_stdout_socket(Server *s);
 
-int stdout_stream_new(Server *s);
 void stdout_stream_free(StdoutStream *s);
-int stdout_stream_process(StdoutStream *s);
diff --git a/src/journal/journald-syslog.c b/src/journal/journald-syslog.c
index 2caa1738d9..80eb9ff2db 100644
--- a/src/journal/journald-syslog.c
+++ b/src/journal/journald-syslog.c
@@ -418,7 +418,6 @@ void server_process_syslog_message(
 
 int server_open_syslog_socket(Server *s) {
         int one, r;
-        struct epoll_event ev;
 
         assert(s);
 
@@ -469,12 +468,10 @@ int server_open_syslog_socket(Server *s) {
                 return -errno;
         }
 
-        zero(ev);
-        ev.events = EPOLLIN;
-        ev.data.fd = s->syslog_fd;
-        if (epoll_ctl(s->epoll_fd, EPOLL_CTL_ADD, s->syslog_fd, &ev) < 0) {
-                log_error("Failed to add syslog server fd to epoll object: %m");
-                return -errno;
+        r = sd_event_add_io(s->event, s->syslog_fd, EPOLLIN, process_datagram, s, &s->syslog_event_source);
+        if (r < 0) {
+                log_error("Failed to add syslog server fd to event loop: %s", strerror(-r));
+                return r;
         }
 
         return 0;
diff --git a/src/journal/journald.c b/src/journal/journald.c
index 5fb10b1d3f..aa12fa785d 100644
--- a/src/journal/journald.c
+++ b/src/journal/journald.c
@@ -70,9 +70,7 @@ int main(int argc, char *argv[]) {
                   "STATUS=Processing requests...");
 
         for (;;) {
-                struct epoll_event event;
-                int t = -1;
-                usec_t n;
+                usec_t t = (usec_t) -1, n;
 
                 n = now(CLOCK_REALTIME);
 
@@ -87,7 +85,7 @@ int main(int argc, char *argv[]) {
                         }
 
                         /* Calculate when to rotate the next time */
-                        t = (int) ((server.oldest_file_usec + server.max_retention_usec - n + USEC_PER_MSEC - 1) / USEC_PER_MSEC);
+                        t = server.oldest_file_usec + server.max_retention_usec - n;
                 }
 
 #ifdef HAVE_GCRYPT
@@ -98,30 +96,18 @@ int main(int argc, char *argv[]) {
                                 if (n >= u)
                                         t = 0;
                                 else
-                                        t = MIN(t, (int) ((u - n + USEC_PER_MSEC - 1) / USEC_PER_MSEC));
+                                        t = MIN(t, u - n);
                         }
                 }
 #endif
 
-                r = epoll_wait(server.epoll_fd, &event, 1, t);
+                r = sd_event_run(server.event, t);
                 if (r < 0) {
-
-                        if (errno == EINTR)
-                                continue;
-
-                        log_error("epoll_wait() failed: %m");
+                        log_error("Failed to run event loop: %s", strerror(-r));
                         r = -errno;
                         goto finish;
                 }
 
-                if (r > 0) {
-                        r = process_event(&server, &event);
-                        if (r < 0)
-                                goto finish;
-                        else if (r == 0)
-                                break;
-                }
-
                 server_maybe_append_tags(&server);
                 server_maybe_warn_forward_syslog_missed(&server);
         }
@@ -130,8 +116,7 @@ int main(int argc, char *argv[]) {
         server_driver_message(&server, SD_MESSAGE_JOURNAL_STOP, "Journal stopped");
 
 finish:
-        sd_notify(false,
-                  "STATUS=Shutting down...");
+        sd_notify(false, "STATUS=Shutting down...");
 
         server_done(&server);
 
diff --git a/units/systemd-journald.service.in b/units/systemd-journald.service.in
index ab2e50c22c..de93879330 100644
--- a/units/systemd-journald.service.in
+++ b/units/systemd-journald.service.in
@@ -20,6 +20,7 @@ RestartSec=0
 NotifyAccess=all
 StandardOutput=null
 CapabilityBoundingSet=CAP_SYS_ADMIN CAP_DAC_OVERRIDE CAP_SYS_PTRACE CAP_SYSLOG CAP_AUDIT_CONTROL CAP_CHOWN CAP_DAC_READ_SEARCH CAP_FOWNER CAP_SETUID CAP_SETGID
+WatchdogSec=1min
 
 # Increase the default a bit in order to allow many simultaneous
 # services being run since we keep one fd open per service.