Systemd/src/core/slice.c
Lennart Poettering 8e2af47840 dbus: add infrastructure for changing multiple properties at once on units and hook some cgroup attributes up to it
This introduces two bus calls to make runtime changes to selected bus
properties, optionally with persistence.

This currently hooks this up only for three cgroup atributes, but this
brings the infrastructure to add more changable attributes.

This allows setting multiple attributes at once, and takes an array
rather than a dictionary of properties, in order to implement simple
resetting of lists using the same approach as when they are sourced from
unit files. This means, that list properties are appended to by this
call, unless they are first reset via assigning the empty list.
2013-06-27 21:14:56 +02:00

320 lines
8.1 KiB
C

/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
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 <signal.h>
#include <unistd.h>
#include "unit.h"
#include "slice.h"
#include "load-fragment.h"
#include "log.h"
#include "dbus-slice.h"
#include "special.h"
#include "unit-name.h"
static const UnitActiveState state_translation_table[_SLICE_STATE_MAX] = {
[SLICE_DEAD] = UNIT_INACTIVE,
[SLICE_ACTIVE] = UNIT_ACTIVE
};
static void slice_init(Unit *u) {
Slice *s = SLICE(u);
assert(u);
assert(u->load_state == UNIT_STUB);
cgroup_context_init(&s->cgroup_context);
}
static void slice_done(Unit *u) {
Slice *s = SLICE(u);
assert(u);
cgroup_context_done(&s->cgroup_context);
}
static void slice_set_state(Slice *t, SliceState state) {
SliceState old_state;
assert(t);
old_state = t->state;
t->state = state;
if (state != old_state)
log_debug("%s changed %s -> %s",
UNIT(t)->id,
slice_state_to_string(old_state),
slice_state_to_string(state));
unit_notify(UNIT(t), state_translation_table[old_state], state_translation_table[state], true);
}
static int slice_add_parent_slice(Slice *s) {
char *a, *dash;
Unit *parent;
int r;
assert(s);
if (UNIT_ISSET(UNIT(s)->slice))
return 0;
if (unit_has_name(UNIT(s), SPECIAL_ROOT_SLICE))
return 0;
a = strdupa(UNIT(s)->id);
dash = strrchr(a, '-');
if (dash)
strcpy(dash, ".slice");
else
a = (char*) SPECIAL_ROOT_SLICE;
r = manager_load_unit(UNIT(s)->manager, a, NULL, NULL, &parent);
if (r < 0)
return r;
unit_ref_set(&UNIT(s)->slice, parent);
return 0;
}
static int slice_add_default_dependencies(Slice *s) {
int r;
assert(s);
/* Make sure slices are unloaded on shutdown */
r = unit_add_dependency_by_name(UNIT(s), UNIT_CONFLICTS, SPECIAL_SHUTDOWN_TARGET, NULL, true);
if (r < 0)
return r;
return 0;
}
static int slice_verify(Slice *s) {
assert(s);
if (UNIT(s)->load_state != UNIT_LOADED)
return 0;
if (UNIT_DEREF(UNIT(s)->slice)) {
char *a, *dash;
a = strdupa(UNIT(s)->id);
dash = strrchr(a, '-');
if (dash)
strcpy(dash, ".slice");
else
a = (char*) SPECIAL_ROOT_SLICE;
if (!unit_has_name(UNIT_DEREF(UNIT(s)->slice), a)) {
log_error_unit(UNIT(s)->id,
"%s located outside its parent slice. Refusing.", UNIT(s)->id);
return -EINVAL;
}
}
return 0;
}
static int slice_load(Unit *u) {
Slice *s = SLICE(u);
int r;
assert(s);
r = unit_load_fragment_and_dropin_optional(u);
if (r < 0)
return r;
/* This is a new unit? Then let's add in some extras */
if (u->load_state == UNIT_LOADED) {
r = slice_add_parent_slice(s);
if (r < 0)
return r;
if (u->default_dependencies) {
r = slice_add_default_dependencies(s);
if (r < 0)
return r;
}
}
return slice_verify(s);
}
static int slice_coldplug(Unit *u) {
Slice *t = SLICE(u);
assert(t);
assert(t->state == SLICE_DEAD);
if (t->deserialized_state != t->state)
slice_set_state(t, t->deserialized_state);
return 0;
}
static void slice_dump(Unit *u, FILE *f, const char *prefix) {
Slice *t = SLICE(u);
assert(t);
assert(f);
fprintf(f,
"%sSlice State: %s\n",
prefix, slice_state_to_string(t->state));
cgroup_context_dump(&t->cgroup_context, f, prefix);
}
static int slice_start(Unit *u) {
Slice *t = SLICE(u);
assert(t);
assert(t->state == SLICE_DEAD);
unit_realize_cgroup(u);
slice_set_state(t, SLICE_ACTIVE);
return 0;
}
static int slice_stop(Unit *u) {
Slice *t = SLICE(u);
assert(t);
assert(t->state == SLICE_ACTIVE);
/* We do not need to destroy the cgroup explicitly,
* unit_notify() will do that for us anyway. */
slice_set_state(t, SLICE_DEAD);
return 0;
}
static int slice_kill(Unit *u, KillWho who, int signo, DBusError *error) {
return unit_kill_common(u, who, signo, -1, -1, error);
}
static int slice_serialize(Unit *u, FILE *f, FDSet *fds) {
Slice *s = SLICE(u);
assert(s);
assert(f);
assert(fds);
unit_serialize_item(u, f, "state", slice_state_to_string(s->state));
return 0;
}
static int slice_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) {
Slice *s = SLICE(u);
assert(u);
assert(key);
assert(value);
assert(fds);
if (streq(key, "state")) {
SliceState state;
state = slice_state_from_string(value);
if (state < 0)
log_debug("Failed to parse state value %s", value);
else
s->deserialized_state = state;
} else
log_debug("Unknown serialization key '%s'", key);
return 0;
}
_pure_ static UnitActiveState slice_active_state(Unit *u) {
assert(u);
return state_translation_table[SLICE(u)->state];
}
_pure_ static const char *slice_sub_state_to_string(Unit *u) {
assert(u);
return slice_state_to_string(SLICE(u)->state);
}
static const char* const slice_state_table[_SLICE_STATE_MAX] = {
[SLICE_DEAD] = "dead",
[SLICE_ACTIVE] = "active"
};
DEFINE_STRING_TABLE_LOOKUP(slice_state, SliceState);
const UnitVTable slice_vtable = {
.object_size = sizeof(Slice),
.sections =
"Unit\0"
"Slice\0"
"Install\0",
.private_section = "Slice",
.cgroup_context_offset = offsetof(Slice, cgroup_context),
.no_alias = true,
.no_instances = true,
.init = slice_init,
.load = slice_load,
.done = slice_done,
.coldplug = slice_coldplug,
.dump = slice_dump,
.start = slice_start,
.stop = slice_stop,
.kill = slice_kill,
.serialize = slice_serialize,
.deserialize_item = slice_deserialize_item,
.active_state = slice_active_state,
.sub_state_to_string = slice_sub_state_to_string,
.bus_interface = "org.freedesktop.systemd1.Slice",
.bus_message_handler = bus_slice_message_handler,
.bus_set_property = bus_slice_set_property,
.bus_commit_properties = bus_slice_commit_properties,
.status_message_formats = {
.finished_start_job = {
[JOB_DONE] = "Created slice %s.",
[JOB_DEPENDENCY] = "Dependency failed for %s.",
},
.finished_stop_job = {
[JOB_DONE] = "Removed slice %s.",
},
},
};