From aada2b1bb29e22e6f19fec6994be09e156e66ce0 Mon Sep 17 00:00:00 2001 From: Sven Eden Date: Mon, 9 Jan 2017 05:53:01 +0100 Subject: [PATCH] Prep v226: Apply missing fixes and changes to src/libelogind --- src/libelogind/sd-bus/bus-match.c | 3 +- src/libelogind/sd-event/sd-event.c | 396 ++++++++++++++++++++--------- src/libelogind/sd-login/sd-login.c | 6 +- 3 files changed, 280 insertions(+), 125 deletions(-) diff --git a/src/libelogind/sd-bus/bus-match.c b/src/libelogind/sd-bus/bus-match.c index 8ef30f55e..b1c000660 100644 --- a/src/libelogind/sd-bus/bus-match.c +++ b/src/libelogind/sd-bus/bus-match.c @@ -934,10 +934,11 @@ fail: /// UNNEEDED by elogind #if 0 char *bus_match_to_string(struct bus_match_component *components, unsigned n_components) { - _cleanup_free_ FILE *f = NULL; + _cleanup_fclose_ FILE *f = NULL; char *buffer = NULL; size_t size = 0; unsigned i; + int r; if (n_components <= 0) return strdup(""); diff --git a/src/libelogind/sd-event/sd-event.c b/src/libelogind/sd-event/sd-event.c index a14ade221..062f19b56 100644 --- a/src/libelogind/sd-event/sd-event.c +++ b/src/libelogind/sd-event/sd-event.c @@ -56,9 +56,22 @@ typedef enum EventSourceType { _SOURCE_EVENT_SOURCE_TYPE_INVALID = -1 } EventSourceType; +/* All objects we use in epoll events start with this value, so that + * we know how to dispatch it */ +typedef enum WakeupType { + WAKEUP_NONE, + WAKEUP_EVENT_SOURCE, + WAKEUP_CLOCK_DATA, + WAKEUP_SIGNAL_DATA, + _WAKEUP_TYPE_MAX, + _WAKEUP_TYPE_INVALID = -1, +} WakeupType; + #define EVENT_SOURCE_IS_TIME(t) IN_SET((t), SOURCE_TIME_REALTIME, SOURCE_TIME_BOOTTIME, SOURCE_TIME_MONOTONIC, SOURCE_TIME_REALTIME_ALARM, SOURCE_TIME_BOOTTIME_ALARM) struct sd_event_source { + WakeupType wakeup; + unsigned n_ref; sd_event *event; @@ -120,6 +133,7 @@ struct sd_event_source { }; struct clock_data { + WakeupType wakeup; int fd; /* For all clocks we maintain two priority queues each, one @@ -136,11 +150,23 @@ struct clock_data { bool needs_rearm:1; }; +struct signal_data { + WakeupType wakeup; + + /* For each priority we maintain one signal fd, so that we + * only have to dequeue a single event per priority at a + * time. */ + + int fd; + int64_t priority; + sigset_t sigset; + sd_event_source *current; +}; + struct sd_event { unsigned n_ref; int epoll_fd; - int signal_fd; int watchdog_fd; Prioq *pending; @@ -157,8 +183,8 @@ struct sd_event { usec_t perturb; - sigset_t sigset; - sd_event_source **signal_sources; + sd_event_source **signal_sources; /* indexed by signal number */ + Hashmap *signal_data; /* indexed by priority */ Hashmap *child_sources; unsigned n_enabled_child_sources; @@ -355,6 +381,7 @@ static int exit_prioq_compare(const void *a, const void *b) { static void free_clock_data(struct clock_data *d) { assert(d); + assert(d->wakeup == WAKEUP_CLOCK_DATA); safe_close(d->fd); prioq_free(d->earliest); @@ -378,7 +405,6 @@ static void event_free(sd_event *e) { *(e->default_event_ptr) = NULL; safe_close(e->epoll_fd); - safe_close(e->signal_fd); safe_close(e->watchdog_fd); free_clock_data(&e->realtime); @@ -392,6 +418,7 @@ static void event_free(sd_event *e) { prioq_free(e->exit); free(e->signal_sources); + hashmap_free(e->signal_data); hashmap_free(e->child_sources); set_free(e->post_sources); @@ -409,13 +436,12 @@ _public_ int sd_event_new(sd_event** ret) { return -ENOMEM; e->n_ref = 1; - e->signal_fd = e->watchdog_fd = e->epoll_fd = e->realtime.fd = e->boottime.fd = e->monotonic.fd = e->realtime_alarm.fd = e->boottime_alarm.fd = -1; + e->watchdog_fd = e->epoll_fd = e->realtime.fd = e->boottime.fd = e->monotonic.fd = e->realtime_alarm.fd = e->boottime_alarm.fd = -1; e->realtime.next = e->boottime.next = e->monotonic.next = e->realtime_alarm.next = e->boottime_alarm.next = USEC_INFINITY; + e->realtime.wakeup = e->boottime.wakeup = e->monotonic.wakeup = e->realtime_alarm.wakeup = e->boottime_alarm.wakeup = WAKEUP_CLOCK_DATA; e->original_pid = getpid(); e->perturb = USEC_INFINITY; - assert_se(sigemptyset(&e->sigset) == 0); - e->pending = prioq_new(pending_prioq_compare); if (!e->pending) { r = -ENOMEM; @@ -509,7 +535,6 @@ static int source_io_register( r = epoll_ctl(s->event->epoll_fd, EPOLL_CTL_MOD, s->io.fd, &ev); else r = epoll_ctl(s->event->epoll_fd, EPOLL_CTL_ADD, s->io.fd, &ev); - if (r < 0) return -errno; @@ -594,45 +619,171 @@ static struct clock_data* event_get_clock_data(sd_event *e, EventSourceType t) { } } -static bool need_signal(sd_event *e, int signal) { - return (e->signal_sources && e->signal_sources[signal] && - e->signal_sources[signal]->enabled != SD_EVENT_OFF) - || - (signal == SIGCHLD && - e->n_enabled_child_sources > 0); -} +static int event_make_signal_data( + sd_event *e, + int sig, + struct signal_data **ret) { -static int event_update_signal_fd(sd_event *e) { struct epoll_event ev = {}; - bool add_to_epoll; + struct signal_data *d; + bool added = false; + sigset_t ss_copy; + int64_t priority; int r; assert(e); if (event_pid_changed(e)) + return -ECHILD; + + if (e->signal_sources && e->signal_sources[sig]) + priority = e->signal_sources[sig]->priority; + else + priority = 0; + + d = hashmap_get(e->signal_data, &priority); + if (d) { + if (sigismember(&d->sigset, sig) > 0) { + if (ret) + *ret = d; return 0; + } + } else { + r = hashmap_ensure_allocated(&e->signal_data, &uint64_hash_ops); + if (r < 0) + return r; - add_to_epoll = e->signal_fd < 0; + d = new0(struct signal_data, 1); + if (!d) + return -ENOMEM; - r = signalfd(e->signal_fd, &e->sigset, SFD_NONBLOCK|SFD_CLOEXEC); + d->wakeup = WAKEUP_SIGNAL_DATA; + d->fd = -1; + d->priority = priority; + + r = hashmap_put(e->signal_data, &d->priority, d); if (r < 0) - return -errno; + return r; + + added = true; + } - e->signal_fd = r; + ss_copy = d->sigset; + assert_se(sigaddset(&ss_copy, sig) >= 0); - if (!add_to_epoll) + r = signalfd(d->fd, &ss_copy, SFD_NONBLOCK|SFD_CLOEXEC); + if (r < 0) { + r = -errno; + goto fail; + } + + d->sigset = ss_copy; + + if (d->fd >= 0) { + if (ret) + *ret = d; return 0; + } + + d->fd = r; ev.events = EPOLLIN; - ev.data.ptr = INT_TO_PTR(SOURCE_SIGNAL); + ev.data.ptr = d; - r = epoll_ctl(e->epoll_fd, EPOLL_CTL_ADD, e->signal_fd, &ev); + r = epoll_ctl(e->epoll_fd, EPOLL_CTL_ADD, d->fd, &ev); if (r < 0) { - e->signal_fd = safe_close(e->signal_fd); - return -errno; + r = -errno; + goto fail; } + if (ret) + *ret = d; + return 0; + +fail: + if (added) { + d->fd = safe_close(d->fd); + hashmap_remove(e->signal_data, &d->priority); + free(d); + } + + return r; +} + +static void event_unmask_signal_data(sd_event *e, struct signal_data *d, int sig) { + assert(e); + assert(d); + + /* Turns off the specified signal in the signal data + * object. If the signal mask of the object becomes empty that + * way removes it. */ + + if (sigismember(&d->sigset, sig) == 0) + return; + + assert_se(sigdelset(&d->sigset, sig) >= 0); + + if (sigisemptyset(&d->sigset)) { + + /* If all the mask is all-zero we can get rid of the structure */ + hashmap_remove(e->signal_data, &d->priority); + assert(!d->current); + safe_close(d->fd); + free(d); + return; + } + + assert(d->fd >= 0); + + if (signalfd(d->fd, &d->sigset, SFD_NONBLOCK|SFD_CLOEXEC) < 0) + log_debug_errno(errno, "Failed to unset signal bit, ignoring: %m"); +} + +static void event_gc_signal_data(sd_event *e, const int64_t *priority, int sig) { + struct signal_data *d; + static const int64_t zero_priority = 0; + + assert(e); + + /* Rechecks if the specified signal is still something we are + * interested in. If not, we'll unmask it, and possibly drop + * the signalfd for it. */ + + if (sig == SIGCHLD && + e->n_enabled_child_sources > 0) + return; + + if (e->signal_sources && + e->signal_sources[sig] && + e->signal_sources[sig]->enabled != SD_EVENT_OFF) + return; + + /* + * The specified signal might be enabled in three different queues: + * + * 1) the one that belongs to the priority passed (if it is non-NULL) + * 2) the one that belongs to the priority of the event source of the signal (if there is one) + * 3) the 0 priority (to cover the SIGCHLD case) + * + * Hence, let's remove it from all three here. + */ + + if (priority) { + d = hashmap_get(e->signal_data, priority); + if (d) + event_unmask_signal_data(e, d, sig); + } + + if (e->signal_sources && e->signal_sources[sig]) { + d = hashmap_get(e->signal_data, &e->signal_sources[sig]->priority); + if (d) + event_unmask_signal_data(e, d, sig); + } + + d = hashmap_get(e->signal_data, &zero_priority); + if (d) + event_unmask_signal_data(e, d, sig); } static void source_disconnect(sd_event_source *s) { @@ -671,17 +822,11 @@ static void source_disconnect(sd_event_source *s) { case SOURCE_SIGNAL: if (s->signal.sig > 0) { + if (s->event->signal_sources) s->event->signal_sources[s->signal.sig] = NULL; - /* If the signal was on and now it is off... */ - if (s->enabled != SD_EVENT_OFF && !need_signal(s->event, s->signal.sig)) { - assert_se(sigdelset(&s->event->sigset, s->signal.sig) == 0); - - (void) event_update_signal_fd(s->event); - /* If disabling failed, we might get a spurious event, - * but otherwise nothing bad should happen. */ - } + event_gc_signal_data(s->event, &s->priority, s->signal.sig); } break; @@ -691,18 +836,10 @@ static void source_disconnect(sd_event_source *s) { if (s->enabled != SD_EVENT_OFF) { assert(s->event->n_enabled_child_sources > 0); s->event->n_enabled_child_sources--; - - /* We know the signal was on, if it is off now... */ - if (!need_signal(s->event, SIGCHLD)) { - assert_se(sigdelset(&s->event->sigset, SIGCHLD) == 0); - - (void) event_update_signal_fd(s->event); - /* If disabling failed, we might get a spurious event, - * but otherwise nothing bad should happen. */ - } } - hashmap_remove(s->event->child_sources, INT_TO_PTR(s->child.pid)); + (void) hashmap_remove(s->event->child_sources, INT_TO_PTR(s->child.pid)); + event_gc_signal_data(s->event, &s->priority, SIGCHLD); } break; @@ -781,6 +918,14 @@ static int source_set_pending(sd_event_source *s, bool b) { d->needs_rearm = true; } + if (s->type == SOURCE_SIGNAL && !b) { + struct signal_data *d; + + d = hashmap_get(s->event->signal_data, &s->priority); + if (d && d->current == s) + d->current = NULL; + } + return 0; } @@ -830,6 +975,7 @@ _public_ int sd_event_add_io( if (!s) return -ENOMEM; + s->wakeup = WAKEUP_EVENT_SOURCE; s->io.fd = fd; s->io.events = events; s->io.callback = callback; @@ -886,7 +1032,7 @@ static int event_setup_timer_fd( return -errno; ev.events = EPOLLIN; - ev.data.ptr = INT_TO_PTR(clock_to_event_source_type(clock)); + ev.data.ptr = d; r = epoll_ctl(e->epoll_fd, EPOLL_CTL_ADD, fd, &ev); if (r < 0) { @@ -996,9 +1142,9 @@ _public_ int sd_event_add_signal( void *userdata) { sd_event_source *s; + struct signal_data *d; sigset_t ss; int r; - bool previous; assert_return(e, -EINVAL); assert_return(sig > 0, -EINVAL); @@ -1023,8 +1169,6 @@ _public_ int sd_event_add_signal( } else if (e->signal_sources[sig]) return -EBUSY; - previous = need_signal(e, sig); - s = source_new(e, !ret, SOURCE_SIGNAL); if (!s) return -ENOMEM; @@ -1036,15 +1180,11 @@ _public_ int sd_event_add_signal( e->signal_sources[sig] = s; - if (!previous) { - assert_se(sigaddset(&e->sigset, sig) == 0); - - r = event_update_signal_fd(e); + r = event_make_signal_data(e, sig, &d); if (r < 0) { source_free(s); return r; } - } /* Use the signal name as description for the event source by default */ (void) sd_event_source_set_description(s, signal_to_string(sig)); @@ -1065,7 +1205,6 @@ _public_ int sd_event_add_child( sd_event_source *s; int r; - bool previous; assert_return(e, -EINVAL); assert_return(pid > 1, -EINVAL); @@ -1082,8 +1221,6 @@ _public_ int sd_event_add_child( if (hashmap_contains(e->child_sources, INT_TO_PTR(pid))) return -EBUSY; - previous = need_signal(e, SIGCHLD); - s = source_new(e, !ret, SOURCE_CHILD); if (!s) return -ENOMEM; @@ -1102,15 +1239,12 @@ _public_ int sd_event_add_child( e->n_enabled_child_sources ++; - if (!previous) { - assert_se(sigaddset(&e->sigset, SIGCHLD) == 0); - - r = event_update_signal_fd(e); + r = event_make_signal_data(e, SIGCHLD, NULL); if (r < 0) { + e->n_enabled_child_sources--; source_free(s); return r; } - } e->need_process_child = true; @@ -1424,6 +1558,8 @@ _public_ int sd_event_source_get_priority(sd_event_source *s, int64_t *priority) #endif // 0 _public_ int sd_event_source_set_priority(sd_event_source *s, int64_t priority) { + int r; + assert_return(s, -EINVAL); assert_return(s->event->state != SD_EVENT_FINISHED, -ESTALE); assert_return(!event_pid_changed(s->event), -ECHILD); @@ -1431,6 +1567,24 @@ _public_ int sd_event_source_set_priority(sd_event_source *s, int64_t priority) if (s->priority == priority) return 0; + if (s->type == SOURCE_SIGNAL && s->enabled != SD_EVENT_OFF) { + struct signal_data *old, *d; + + /* Move us from the signalfd belonging to the old + * priority to the signalfd of the new priority */ + + assert_se(old = hashmap_get(s->event->signal_data, &s->priority)); + + s->priority = priority; + + r = event_make_signal_data(s->event, s->signal.sig, &d); + if (r < 0) { + s->priority = old->priority; + return r; + } + + event_unmask_signal_data(s->event, old, s->signal.sig); + } else s->priority = priority; if (s->pending) @@ -1499,34 +1653,18 @@ _public_ int sd_event_source_set_enabled(sd_event_source *s, int m) { } case SOURCE_SIGNAL: - assert(need_signal(s->event, s->signal.sig)); - s->enabled = m; - if (!need_signal(s->event, s->signal.sig)) { - assert_se(sigdelset(&s->event->sigset, s->signal.sig) == 0); - - (void) event_update_signal_fd(s->event); - /* If disabling failed, we might get a spurious event, - * but otherwise nothing bad should happen. */ - } - + event_gc_signal_data(s->event, &s->priority, s->signal.sig); break; case SOURCE_CHILD: - assert(need_signal(s->event, SIGCHLD)); - s->enabled = m; assert(s->event->n_enabled_child_sources > 0); s->event->n_enabled_child_sources--; - if (!need_signal(s->event, SIGCHLD)) { - assert_se(sigdelset(&s->event->sigset, SIGCHLD) == 0); - - (void) event_update_signal_fd(s->event); - } - + event_gc_signal_data(s->event, &s->priority, SIGCHLD); break; case SOURCE_EXIT: @@ -1572,37 +1710,33 @@ _public_ int sd_event_source_set_enabled(sd_event_source *s, int m) { } case SOURCE_SIGNAL: - /* Check status before enabling. */ - if (!need_signal(s->event, s->signal.sig)) { - assert_se(sigaddset(&s->event->sigset, s->signal.sig) == 0); - r = event_update_signal_fd(s->event); + s->enabled = m; + + r = event_make_signal_data(s->event, s->signal.sig, NULL); if (r < 0) { s->enabled = SD_EVENT_OFF; + event_gc_signal_data(s->event, &s->priority, s->signal.sig); return r; } - } - s->enabled = m; break; case SOURCE_CHILD: - /* Check status before enabling. */ - if (s->enabled == SD_EVENT_OFF) { - if (!need_signal(s->event, SIGCHLD)) { - assert_se(sigaddset(&s->event->sigset, s->signal.sig) == 0); - r = event_update_signal_fd(s->event); + if (s->enabled == SD_EVENT_OFF) + s->event->n_enabled_child_sources++; + + s->enabled = m; + + r = event_make_signal_data(s->event, SIGCHLD, NULL); if (r < 0) { s->enabled = SD_EVENT_OFF; + s->event->n_enabled_child_sources--; + event_gc_signal_data(s->event, &s->priority, SIGCHLD); return r; } - } - s->event->n_enabled_child_sources++; - } - - s->enabled = m; break; case SOURCE_EXIT: @@ -2052,20 +2186,35 @@ static int process_child(sd_event *e) { return 0; } -static int process_signal(sd_event *e, uint32_t events) { +static int process_signal(sd_event *e, struct signal_data *d, uint32_t events) { bool read_one = false; int r; assert(e); - assert_return(events == EPOLLIN, -EIO); + /* If there's a signal queued on this priority and SIGCHLD is + on this priority too, then make sure to recheck the + children we watch. This is because we only ever dequeue + the first signal per priority, and if we dequeue one, and + SIGCHLD might be enqueued later we wouldn't know, but we + might have higher priority children we care about hence we + need to check that explicitly. */ + + if (sigismember(&d->sigset, SIGCHLD)) + e->need_process_child = true; + + /* If there's already an event source pending for this + * priority we don't read another */ + if (d->current) + return 0; + for (;;) { struct signalfd_siginfo si; ssize_t n; sd_event_source *s = NULL; - n = read(e->signal_fd, &si, sizeof(si)); + n = read(d->fd, &si, sizeof(si)); if (n < 0) { if (errno == EAGAIN || errno == EINTR) return read_one; @@ -2080,24 +2229,21 @@ static int process_signal(sd_event *e, uint32_t events) { read_one = true; - if (si.ssi_signo == SIGCHLD) { - r = process_child(e); - if (r < 0) - return r; - if (r > 0) - continue; - } - if (e->signal_sources) s = e->signal_sources[si.ssi_signo]; - if (!s) continue; + if (s->pending) + continue; s->signal.siginfo = si; + d->current = s; + r = source_set_pending(s, true); if (r < 0) return r; + + return 1; } } @@ -2415,23 +2561,31 @@ _public_ int sd_event_wait(sd_event *e, uint64_t timeout) { for (i = 0; i < m; i++) { - if (ev_queue[i].data.ptr == INT_TO_PTR(SOURCE_TIME_REALTIME)) - r = flush_timer(e, e->realtime.fd, ev_queue[i].events, &e->realtime.next); - else if (ev_queue[i].data.ptr == INT_TO_PTR(SOURCE_TIME_BOOTTIME)) - r = flush_timer(e, e->boottime.fd, ev_queue[i].events, &e->boottime.next); - else if (ev_queue[i].data.ptr == INT_TO_PTR(SOURCE_TIME_MONOTONIC)) - r = flush_timer(e, e->monotonic.fd, ev_queue[i].events, &e->monotonic.next); - else if (ev_queue[i].data.ptr == INT_TO_PTR(SOURCE_TIME_REALTIME_ALARM)) - r = flush_timer(e, e->realtime_alarm.fd, ev_queue[i].events, &e->realtime_alarm.next); - else if (ev_queue[i].data.ptr == INT_TO_PTR(SOURCE_TIME_BOOTTIME_ALARM)) - r = flush_timer(e, e->boottime_alarm.fd, ev_queue[i].events, &e->boottime_alarm.next); - else if (ev_queue[i].data.ptr == INT_TO_PTR(SOURCE_SIGNAL)) - r = process_signal(e, ev_queue[i].events); - else if (ev_queue[i].data.ptr == INT_TO_PTR(SOURCE_WATCHDOG)) + if (ev_queue[i].data.ptr == INT_TO_PTR(SOURCE_WATCHDOG)) r = flush_timer(e, e->watchdog_fd, ev_queue[i].events, NULL); - else + else { + WakeupType *t = ev_queue[i].data.ptr; + + switch (*t) { + + case WAKEUP_EVENT_SOURCE: r = process_io(e, ev_queue[i].data.ptr, ev_queue[i].events); + break; + case WAKEUP_CLOCK_DATA: { + struct clock_data *d = ev_queue[i].data.ptr; + r = flush_timer(e, d->fd, ev_queue[i].events, &d->next); + break; + } + + case WAKEUP_SIGNAL_DATA: + r = process_signal(e, ev_queue[i].data.ptr, ev_queue[i].events); + break; + + default: + assert_not_reached("Invalid wake-up pointer"); + } + } if (r < 0) goto finish; } diff --git a/src/libelogind/sd-login/sd-login.c b/src/libelogind/sd-login/sd-login.c index 55da26e9d..f4dd7feec 100644 --- a/src/libelogind/sd-login/sd-login.c +++ b/src/libelogind/sd-login/sd-login.c @@ -108,7 +108,7 @@ _public_ int sd_pid_get_cgroup(pid_t pid, char **cgroup) { assert_return(pid >= 0, -EINVAL); assert_return(cgroup, -EINVAL); - r = cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, pid, &c); + r = cg_pid_get_path(ELOGIND_CGROUP_CONTROLLER, pid, &c); if (r < 0) return r; @@ -645,10 +645,10 @@ _public_ int sd_seat_get_active(const char *seat, char **session, uid_t *uid) { return r; if (session && !s) - return -ENOENT; + return -ENODATA; if (uid && !t) - return -ENOENT; + return -ENODATA; if (uid && t) { r = parse_uid(t, uid); -- 2.30.2