summaryrefslogtreecommitdiff
path: root/src/libcore/scope.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/libcore/scope.c')
-rw-r--r--src/libcore/scope.c610
1 files changed, 610 insertions, 0 deletions
diff --git a/src/libcore/scope.c b/src/libcore/scope.c
new file mode 100644
index 0000000000..c5d0ecef04
--- /dev/null
+++ b/src/libcore/scope.c
@@ -0,0 +1,610 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2013 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <errno.h>
+#include <unistd.h>
+
+#include "alloc-util.h"
+#include "dbus-scope.h"
+#include "load-dropin.h"
+#include "log.h"
+#include "scope.h"
+#include "special.h"
+#include "string-table.h"
+#include "string-util.h"
+#include "strv.h"
+#include "unit-name.h"
+#include "unit.h"
+
+static const UnitActiveState state_translation_table[_SCOPE_STATE_MAX] = {
+ [SCOPE_DEAD] = UNIT_INACTIVE,
+ [SCOPE_RUNNING] = UNIT_ACTIVE,
+ [SCOPE_ABANDONED] = UNIT_ACTIVE,
+ [SCOPE_STOP_SIGTERM] = UNIT_DEACTIVATING,
+ [SCOPE_STOP_SIGKILL] = UNIT_DEACTIVATING,
+ [SCOPE_FAILED] = UNIT_FAILED
+};
+
+static int scope_dispatch_timer(sd_event_source *source, usec_t usec, void *userdata);
+
+static void scope_init(Unit *u) {
+ Scope *s = SCOPE(u);
+
+ assert(u);
+ assert(u->load_state == UNIT_STUB);
+
+ s->timeout_stop_usec = u->manager->default_timeout_stop_usec;
+
+ UNIT(s)->ignore_on_isolate = true;
+}
+
+static void scope_done(Unit *u) {
+ Scope *s = SCOPE(u);
+
+ assert(u);
+
+ free(s->controller);
+
+ s->timer_event_source = sd_event_source_unref(s->timer_event_source);
+}
+
+static int scope_arm_timer(Scope *s, usec_t usec) {
+ int r;
+
+ assert(s);
+
+ if (s->timer_event_source) {
+ r = sd_event_source_set_time(s->timer_event_source, usec);
+ if (r < 0)
+ return r;
+
+ return sd_event_source_set_enabled(s->timer_event_source, SD_EVENT_ONESHOT);
+ }
+
+ if (usec == USEC_INFINITY)
+ return 0;
+
+ r = sd_event_add_time(
+ UNIT(s)->manager->event,
+ &s->timer_event_source,
+ CLOCK_MONOTONIC,
+ usec, 0,
+ scope_dispatch_timer, s);
+ if (r < 0)
+ return r;
+
+ (void) sd_event_source_set_description(s->timer_event_source, "scope-timer");
+
+ return 0;
+}
+
+static void scope_set_state(Scope *s, ScopeState state) {
+ ScopeState old_state;
+ assert(s);
+
+ old_state = s->state;
+ s->state = state;
+
+ if (!IN_SET(state, SCOPE_STOP_SIGTERM, SCOPE_STOP_SIGKILL))
+ s->timer_event_source = sd_event_source_unref(s->timer_event_source);
+
+ if (IN_SET(state, SCOPE_DEAD, SCOPE_FAILED))
+ unit_unwatch_all_pids(UNIT(s));
+
+ if (state != old_state)
+ log_debug("%s changed %s -> %s", UNIT(s)->id, scope_state_to_string(old_state), scope_state_to_string(state));
+
+ unit_notify(UNIT(s), state_translation_table[old_state], state_translation_table[state], true);
+}
+
+static int scope_add_default_dependencies(Scope *s) {
+ int r;
+
+ assert(s);
+
+ if (!UNIT(s)->default_dependencies)
+ return 0;
+
+ /* Make sure scopes are unloaded on shutdown */
+ r = unit_add_two_dependencies_by_name(
+ UNIT(s),
+ UNIT_BEFORE, UNIT_CONFLICTS,
+ SPECIAL_SHUTDOWN_TARGET, NULL, true);
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+static int scope_verify(Scope *s) {
+ assert(s);
+
+ if (UNIT(s)->load_state != UNIT_LOADED)
+ return 0;
+
+ if (set_isempty(UNIT(s)->pids) &&
+ !manager_is_reloading_or_reexecuting(UNIT(s)->manager) &&
+ !unit_has_name(UNIT(s), SPECIAL_INIT_SCOPE)) {
+ log_unit_error(UNIT(s), "Scope has no PIDs. Refusing.");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int scope_load(Unit *u) {
+ Scope *s = SCOPE(u);
+ int r;
+
+ assert(s);
+ assert(u->load_state == UNIT_STUB);
+
+ if (!u->transient && !manager_is_reloading_or_reexecuting(u->manager))
+ return -ENOENT;
+
+ u->load_state = UNIT_LOADED;
+
+ r = unit_load_dropin(u);
+ if (r < 0)
+ return r;
+
+ r = unit_patch_contexts(u);
+ if (r < 0)
+ return r;
+
+ r = unit_set_default_slice(u);
+ if (r < 0)
+ return r;
+
+ r = scope_add_default_dependencies(s);
+ if (r < 0)
+ return r;
+
+ return scope_verify(s);
+}
+
+static int scope_coldplug(Unit *u) {
+ Scope *s = SCOPE(u);
+ int r;
+
+ assert(s);
+ assert(s->state == SCOPE_DEAD);
+
+ if (s->deserialized_state == s->state)
+ return 0;
+
+ if (IN_SET(s->deserialized_state, SCOPE_STOP_SIGKILL, SCOPE_STOP_SIGTERM)) {
+ r = scope_arm_timer(s, usec_add(u->state_change_timestamp.monotonic, s->timeout_stop_usec));
+ if (r < 0)
+ return r;
+ }
+
+ if (!IN_SET(s->deserialized_state, SCOPE_DEAD, SCOPE_FAILED))
+ unit_watch_all_pids(UNIT(s));
+
+ scope_set_state(s, s->deserialized_state);
+ return 0;
+}
+
+static void scope_dump(Unit *u, FILE *f, const char *prefix) {
+ Scope *s = SCOPE(u);
+
+ assert(s);
+ assert(f);
+
+ fprintf(f,
+ "%sScope State: %s\n"
+ "%sResult: %s\n",
+ prefix, scope_state_to_string(s->state),
+ prefix, scope_result_to_string(s->result));
+
+ cgroup_context_dump(&s->cgroup_context, f, prefix);
+ kill_context_dump(&s->kill_context, f, prefix);
+}
+
+static void scope_enter_dead(Scope *s, ScopeResult f) {
+ assert(s);
+
+ if (f != SCOPE_SUCCESS)
+ s->result = f;
+
+ scope_set_state(s, s->result != SCOPE_SUCCESS ? SCOPE_FAILED : SCOPE_DEAD);
+}
+
+static void scope_enter_signal(Scope *s, ScopeState state, ScopeResult f) {
+ bool skip_signal = false;
+ int r;
+
+ assert(s);
+
+ if (f != SCOPE_SUCCESS)
+ s->result = f;
+
+ unit_watch_all_pids(UNIT(s));
+
+ /* If we have a controller set let's ask the controller nicely
+ * to terminate the scope, instead of us going directly into
+ * SIGTERM beserk mode */
+ if (state == SCOPE_STOP_SIGTERM)
+ skip_signal = bus_scope_send_request_stop(s) > 0;
+
+ if (!skip_signal) {
+ r = unit_kill_context(
+ UNIT(s),
+ &s->kill_context,
+ state != SCOPE_STOP_SIGTERM ? KILL_KILL : KILL_TERMINATE,
+ -1, -1, false);
+ if (r < 0)
+ goto fail;
+ } else
+ r = 1;
+
+ if (r > 0) {
+ r = scope_arm_timer(s, usec_add(now(CLOCK_MONOTONIC), s->timeout_stop_usec));
+ if (r < 0)
+ goto fail;
+
+ scope_set_state(s, state);
+ } else if (state == SCOPE_STOP_SIGTERM)
+ scope_enter_signal(s, SCOPE_STOP_SIGKILL, SCOPE_SUCCESS);
+ else
+ scope_enter_dead(s, SCOPE_SUCCESS);
+
+ return;
+
+fail:
+ log_unit_warning_errno(UNIT(s), r, "Failed to kill processes: %m");
+
+ scope_enter_dead(s, SCOPE_FAILURE_RESOURCES);
+}
+
+static int scope_start(Unit *u) {
+ Scope *s = SCOPE(u);
+ int r;
+
+ assert(s);
+
+ if (unit_has_name(u, SPECIAL_INIT_SCOPE))
+ return -EPERM;
+
+ if (s->state == SCOPE_FAILED)
+ return -EPERM;
+
+ /* We can't fulfill this right now, please try again later */
+ if (s->state == SCOPE_STOP_SIGTERM ||
+ s->state == SCOPE_STOP_SIGKILL)
+ return -EAGAIN;
+
+ assert(s->state == SCOPE_DEAD);
+
+ if (!u->transient && !manager_is_reloading_or_reexecuting(u->manager))
+ return -ENOENT;
+
+ (void) unit_realize_cgroup(u);
+ (void) unit_reset_cpu_usage(u);
+
+ r = unit_attach_pids_to_cgroup(u);
+ if (r < 0) {
+ log_unit_warning_errno(UNIT(s), r, "Failed to add PIDs to scope's control group: %m");
+ scope_enter_dead(s, SCOPE_FAILURE_RESOURCES);
+ return r;
+ }
+
+ s->result = SCOPE_SUCCESS;
+
+ scope_set_state(s, SCOPE_RUNNING);
+ return 1;
+}
+
+static int scope_stop(Unit *u) {
+ Scope *s = SCOPE(u);
+
+ assert(s);
+
+ if (s->state == SCOPE_STOP_SIGTERM ||
+ s->state == SCOPE_STOP_SIGKILL)
+ return 0;
+
+ assert(s->state == SCOPE_RUNNING ||
+ s->state == SCOPE_ABANDONED);
+
+ scope_enter_signal(s, SCOPE_STOP_SIGTERM, SCOPE_SUCCESS);
+ return 1;
+}
+
+static void scope_reset_failed(Unit *u) {
+ Scope *s = SCOPE(u);
+
+ assert(s);
+
+ if (s->state == SCOPE_FAILED)
+ scope_set_state(s, SCOPE_DEAD);
+
+ s->result = SCOPE_SUCCESS;
+}
+
+static int scope_kill(Unit *u, KillWho who, int signo, sd_bus_error *error) {
+ return unit_kill_common(u, who, signo, -1, -1, error);
+}
+
+static int scope_get_timeout(Unit *u, usec_t *timeout) {
+ Scope *s = SCOPE(u);
+ usec_t t;
+ int r;
+
+ if (!s->timer_event_source)
+ return 0;
+
+ r = sd_event_source_get_time(s->timer_event_source, &t);
+ if (r < 0)
+ return r;
+ if (t == USEC_INFINITY)
+ return 0;
+
+ *timeout = t;
+ return 1;
+}
+
+static int scope_serialize(Unit *u, FILE *f, FDSet *fds) {
+ Scope *s = SCOPE(u);
+
+ assert(s);
+ assert(f);
+ assert(fds);
+
+ unit_serialize_item(u, f, "state", scope_state_to_string(s->state));
+ return 0;
+}
+
+static int scope_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) {
+ Scope *s = SCOPE(u);
+
+ assert(u);
+ assert(key);
+ assert(value);
+ assert(fds);
+
+ if (streq(key, "state")) {
+ ScopeState state;
+
+ state = scope_state_from_string(value);
+ if (state < 0)
+ log_unit_debug(u, "Failed to parse state value: %s", value);
+ else
+ s->deserialized_state = state;
+
+ } else
+ log_unit_debug(u, "Unknown serialization key: %s", key);
+
+ return 0;
+}
+
+static bool scope_check_gc(Unit *u) {
+ assert(u);
+
+ /* Never clean up scopes that still have a process around,
+ * even if the scope is formally dead. */
+
+ if (!u->cgroup_path)
+ return false;
+
+ return cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path) <= 0;
+}
+
+static void scope_notify_cgroup_empty_event(Unit *u) {
+ Scope *s = SCOPE(u);
+ assert(u);
+
+ log_unit_debug(u, "cgroup is empty");
+
+ if (IN_SET(s->state, SCOPE_RUNNING, SCOPE_ABANDONED, SCOPE_STOP_SIGTERM, SCOPE_STOP_SIGKILL))
+ scope_enter_dead(s, SCOPE_SUCCESS);
+}
+
+static void scope_sigchld_event(Unit *u, pid_t pid, int code, int status) {
+
+ /* If we get a SIGCHLD event for one of the processes we were
+ interested in, then we look for others to watch, under the
+ assumption that we'll sooner or later get a SIGCHLD for
+ them, as the original process we watched was probably the
+ parent of them, and they are hence now our children. */
+
+ unit_tidy_watch_pids(u, 0, 0);
+ unit_watch_all_pids(u);
+
+ /* If the PID set is empty now, then let's finish this off */
+ if (set_isempty(u->pids))
+ scope_notify_cgroup_empty_event(u);
+}
+
+static int scope_dispatch_timer(sd_event_source *source, usec_t usec, void *userdata) {
+ Scope *s = SCOPE(userdata);
+
+ assert(s);
+ assert(s->timer_event_source == source);
+
+ switch (s->state) {
+
+ case SCOPE_STOP_SIGTERM:
+ if (s->kill_context.send_sigkill) {
+ log_unit_warning(UNIT(s), "Stopping timed out. Killing.");
+ scope_enter_signal(s, SCOPE_STOP_SIGKILL, SCOPE_FAILURE_TIMEOUT);
+ } else {
+ log_unit_warning(UNIT(s), "Stopping timed out. Skipping SIGKILL.");
+ scope_enter_dead(s, SCOPE_FAILURE_TIMEOUT);
+ }
+
+ break;
+
+ case SCOPE_STOP_SIGKILL:
+ log_unit_warning(UNIT(s), "Still around after SIGKILL. Ignoring.");
+ scope_enter_dead(s, SCOPE_FAILURE_TIMEOUT);
+ break;
+
+ default:
+ assert_not_reached("Timeout at wrong time.");
+ }
+
+ return 0;
+}
+
+int scope_abandon(Scope *s) {
+ assert(s);
+
+ if (unit_has_name(UNIT(s), SPECIAL_INIT_SCOPE))
+ return -EPERM;
+
+ if (!IN_SET(s->state, SCOPE_RUNNING, SCOPE_ABANDONED))
+ return -ESTALE;
+
+ s->controller = mfree(s->controller);
+
+ /* The client is no longer watching the remaining processes,
+ * so let's step in here, under the assumption that the
+ * remaining processes will be sooner or later reassigned to
+ * us as parent. */
+
+ unit_tidy_watch_pids(UNIT(s), 0, 0);
+ unit_watch_all_pids(UNIT(s));
+
+ /* If the PID set is empty now, then let's finish this off */
+ if (set_isempty(UNIT(s)->pids))
+ scope_notify_cgroup_empty_event(UNIT(s));
+ else
+ scope_set_state(s, SCOPE_ABANDONED);
+
+ return 0;
+}
+
+_pure_ static UnitActiveState scope_active_state(Unit *u) {
+ assert(u);
+
+ return state_translation_table[SCOPE(u)->state];
+}
+
+_pure_ static const char *scope_sub_state_to_string(Unit *u) {
+ assert(u);
+
+ return scope_state_to_string(SCOPE(u)->state);
+}
+
+static void scope_enumerate(Manager *m) {
+ Unit *u;
+ int r;
+
+ assert(m);
+
+ /* Let's unconditionally add the "init.scope" special unit
+ * that encapsulates PID 1. Note that PID 1 already is in the
+ * cgroup for this, we hence just need to allocate the object
+ * for it and that's it. */
+
+ u = manager_get_unit(m, SPECIAL_INIT_SCOPE);
+ if (!u) {
+ u = unit_new(m, sizeof(Scope));
+ if (!u) {
+ log_oom();
+ return;
+ }
+
+ r = unit_add_name(u, SPECIAL_INIT_SCOPE);
+ if (r < 0) {
+ unit_free(u);
+ log_error_errno(r, "Failed to add init.scope name");
+ return;
+ }
+ }
+
+ u->transient = true;
+ u->default_dependencies = false;
+ u->no_gc = true;
+ u->ignore_on_isolate = true;
+ u->refuse_manual_start = true;
+ u->refuse_manual_stop = true;
+ SCOPE(u)->deserialized_state = SCOPE_RUNNING;
+ SCOPE(u)->kill_context.kill_signal = SIGRTMIN+14;
+
+ /* Prettify things, if we can. */
+ if (!u->description)
+ u->description = strdup("System and Service Manager");
+ if (!u->documentation)
+ (void) strv_extend(&u->documentation, "man:systemd(1)");
+
+ unit_add_to_load_queue(u);
+ unit_add_to_dbus_queue(u);
+}
+
+static const char* const scope_result_table[_SCOPE_RESULT_MAX] = {
+ [SCOPE_SUCCESS] = "success",
+ [SCOPE_FAILURE_RESOURCES] = "resources",
+ [SCOPE_FAILURE_TIMEOUT] = "timeout",
+};
+
+DEFINE_STRING_TABLE_LOOKUP(scope_result, ScopeResult);
+
+const UnitVTable scope_vtable = {
+ .object_size = sizeof(Scope),
+ .cgroup_context_offset = offsetof(Scope, cgroup_context),
+ .kill_context_offset = offsetof(Scope, kill_context),
+
+ .sections =
+ "Unit\0"
+ "Scope\0"
+ "Install\0",
+ .private_section = "Scope",
+
+ .no_alias = true,
+ .no_instances = true,
+ .can_transient = true,
+
+ .init = scope_init,
+ .load = scope_load,
+ .done = scope_done,
+
+ .coldplug = scope_coldplug,
+
+ .dump = scope_dump,
+
+ .start = scope_start,
+ .stop = scope_stop,
+
+ .kill = scope_kill,
+
+ .get_timeout = scope_get_timeout,
+
+ .serialize = scope_serialize,
+ .deserialize_item = scope_deserialize_item,
+
+ .active_state = scope_active_state,
+ .sub_state_to_string = scope_sub_state_to_string,
+
+ .check_gc = scope_check_gc,
+
+ .sigchld_event = scope_sigchld_event,
+
+ .reset_failed = scope_reset_failed,
+
+ .notify_cgroup_empty = scope_notify_cgroup_empty_event,
+
+ .bus_vtable = bus_scope_vtable,
+ .bus_set_property = bus_scope_set_property,
+ .bus_commit_properties = bus_scope_commit_properties,
+
+ .enumerate = scope_enumerate,
+};