/***
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 .
***/
#include
#include
#include "basic/alloc-util.h"
#include "dbus-scope.h"
#include "load-dropin.h"
#include "basic/log.h"
#include "scope.h"
#include "basic/special.h"
#include "basic/string-table.h"
#include "basic/string-util.h"
#include "basic/strv.h"
#include "basic/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;
u->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(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(u->manager))
/* Refuse to load non-transient scope units, but allow them while reloading. */
return -ENOENT;
r = unit_load_fragment_and_dropin_optional(u);
if (r < 0)
return r;
if (u->load_state == UNIT_LOADED) {
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(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",
.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,
};