Adding upstream version 252.22.upstream/252.22upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 471 insertions, 0 deletions

diff --git a/src/core/slice.c b/src/core/slice.c
new file mode 100644
index 0000000..a6c71e8
--- /dev/null
+++ b/src/core/slice.c
@@ -0,0 +1,471 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <errno.h>
+
+#include "alloc-util.h"
+#include "dbus-slice.h"
+#include "dbus-unit.h"
+#include "fd-util.h"
+#include "log.h"
+#include "serialize.h"
+#include "slice.h"
+#include "special.h"
+#include "string-util.h"
+#include "strv.h"
+#include "unit-name.h"
+#include "unit.h"
+
+static const UnitActiveState state_translation_table[_SLICE_STATE_MAX] = {
+        [SLICE_DEAD] = UNIT_INACTIVE,
+        [SLICE_ACTIVE] = UNIT_ACTIVE
+};
+
+static void slice_init(Unit *u) {
+        assert(u);
+        assert(u->load_state == UNIT_STUB);
+
+        u->ignore_on_isolate = true;
+}
+
+static void slice_set_state(Slice *t, SliceState state) {
+        SliceState old_state;
+        assert(t);
+
+        if (t->state != state)
+                bus_unit_send_pending_change_signal(UNIT(t), false);
+
+        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], 0);
+}
+
+static int slice_add_parent_slice(Slice *s) {
+        Unit *u = UNIT(s);
+        _cleanup_free_ char *a = NULL;
+        int r;
+
+        assert(s);
+
+        if (UNIT_GET_SLICE(u))
+                return 0;
+
+        r = slice_build_parent_slice(u->id, &a);
+        if (r <= 0) /* 0 means root slice */
+                return r;
+
+        return unit_add_dependency_by_name(u, UNIT_IN_SLICE, a, true, UNIT_DEPENDENCY_IMPLICIT);
+}
+
+static int slice_add_default_dependencies(Slice *s) {
+        int r;
+
+        assert(s);
+
+        if (!UNIT(s)->default_dependencies)
+                return 0;
+
+        /* Make sure slices are unloaded on shutdown */
+        r = unit_add_two_dependencies_by_name(
+                        UNIT(s),
+                        UNIT_BEFORE, UNIT_CONFLICTS,
+                        SPECIAL_SHUTDOWN_TARGET, true, UNIT_DEPENDENCY_DEFAULT);
+        if (r < 0)
+                return r;
+
+        return 0;
+}
+
+static int slice_verify(Slice *s) {
+        _cleanup_free_ char *parent = NULL;
+        int r;
+
+        assert(s);
+        assert(UNIT(s)->load_state == UNIT_LOADED);
+
+        if (!slice_name_is_valid(UNIT(s)->id))
+                return log_unit_error_errno(UNIT(s), SYNTHETIC_ERRNO(ENOEXEC), "Slice name %s is not valid. Refusing.", UNIT(s)->id);
+
+        r = slice_build_parent_slice(UNIT(s)->id, &parent);
+        if (r < 0)
+                return log_unit_error_errno(UNIT(s), r, "Failed to determine parent slice: %m");
+
+        /* If recursive errors are to be ignored, the parent slice should not be verified */
+        if (UNIT(s)->manager && FLAGS_SET(UNIT(s)->manager->test_run_flags, MANAGER_TEST_RUN_IGNORE_DEPENDENCIES))
+                return 0;
+
+        if (parent ? !unit_has_name(UNIT_GET_SLICE(UNIT(s)), parent) : !!UNIT_GET_SLICE(UNIT(s)))
+                return log_unit_error_errno(UNIT(s), SYNTHETIC_ERRNO(ENOEXEC), "Located outside of parent slice. Refusing.");
+
+        return 0;
+}
+
+static int slice_load_root_slice(Unit *u) {
+        assert(u);
+
+        if (!unit_has_name(u, SPECIAL_ROOT_SLICE))
+                return 0;
+
+        u->perpetual = true;
+
+        /* The root slice is a bit special. For example it is always running and cannot be terminated. Because of its
+         * special semantics we synthesize it here, instead of relying on the unit file on disk. */
+
+        u->default_dependencies = false;
+
+        if (!u->description)
+                u->description = strdup("Root Slice");
+        if (!u->documentation)
+                u->documentation = strv_new("man:systemd.special(7)");
+
+        return 1;
+}
+
+static int slice_load_system_slice(Unit *u) {
+        assert(u);
+
+        if (!MANAGER_IS_SYSTEM(u->manager))
+                return 0;
+        if (!unit_has_name(u, SPECIAL_SYSTEM_SLICE))
+                return 0;
+
+        u->perpetual = true;
+
+        /* The system slice is a bit special. For example it is always running and cannot be terminated. Because of its
+         * special semantics we synthesize it here, instead of relying on the unit file on disk. */
+
+        u->default_dependencies = false;
+
+        if (!u->description)
+                u->description = strdup("System Slice");
+        if (!u->documentation)
+                u->documentation = strv_new("man:systemd.special(7)");
+
+        return 1;
+}
+
+static int slice_load(Unit *u) {
+        Slice *s = SLICE(u);
+        int r;
+
+        assert(s);
+        assert(u->load_state == UNIT_STUB);
+
+        r = slice_load_root_slice(u);
+        if (r < 0)
+                return r;
+        r = slice_load_system_slice(u);
+        if (r < 0)
+                return r;
+
+        r = unit_load_fragment_and_dropin(u, false);
+        if (r < 0)
+                return r;
+
+        if (u->load_state != UNIT_LOADED)
+                return 0;
+
+        /* This is a new unit? Then let's add in some extras */
+        r = unit_patch_contexts(u);
+        if (r < 0)
+                return r;
+
+        r = slice_add_parent_slice(s);
+        if (r < 0)
+                return r;
+
+        r = slice_add_default_dependencies(s);
+        if (r < 0)
+                return r;
+
+        if (!u->description) {
+                _cleanup_free_ char *tmp = NULL;
+
+                r = unit_name_to_path(u->id, &tmp);
+                if (r >= 0)  /* Failure is ignored… */
+                        u->description = strjoin("Slice ", tmp);
+        }
+
+        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(UNIT(t), f, prefix);
+}
+
+static int slice_start(Unit *u) {
+        Slice *t = SLICE(u);
+        int r;
+
+        assert(t);
+        assert(t->state == SLICE_DEAD);
+
+        r = unit_acquire_invocation_id(u);
+        if (r < 0)
+                return r;
+
+        (void) unit_realize_cgroup(u);
+        (void) unit_reset_accounting(u);
+
+        slice_set_state(t, SLICE_ACTIVE);
+        return 1;
+}
+
+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 1;
+}
+
+static int slice_kill(Unit *u, KillWho who, int signo, sd_bus_error *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);
+
+        (void) serialize_item(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 int slice_make_perpetual(Manager *m, const char *name, Unit **ret) {
+        Unit *u;
+        int r;
+
+        assert(m);
+        assert(name);
+
+        u = manager_get_unit(m, name);
+        if (!u) {
+                r = unit_new_for_name(m, sizeof(Slice), name, &u);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to allocate the special %s unit: %m", name);
+        }
+
+        u->perpetual = true;
+        SLICE(u)->deserialized_state = SLICE_ACTIVE;
+
+        unit_add_to_load_queue(u);
+        unit_add_to_dbus_queue(u);
+
+        if (ret)
+                *ret = u;
+
+        return 0;
+}
+
+static void slice_enumerate_perpetual(Manager *m) {
+        Unit *u;
+        int r;
+
+        assert(m);
+
+        r = slice_make_perpetual(m, SPECIAL_ROOT_SLICE, &u);
+        if (r >= 0 && manager_owns_host_root_cgroup(m)) {
+                Slice *s = SLICE(u);
+
+                /* If we are managing the root cgroup then this means our root slice covers the whole system, which
+                 * means the kernel will track CPU/tasks/memory for us anyway, and it is all available in /proc. Let's
+                 * hence turn accounting on here, so that our APIs to query this data are available. */
+
+                s->cgroup_context.cpu_accounting = true;
+                s->cgroup_context.tasks_accounting = true;
+                s->cgroup_context.memory_accounting = true;
+        }
+
+        if (MANAGER_IS_SYSTEM(m))
+                (void) slice_make_perpetual(m, SPECIAL_SYSTEM_SLICE, NULL);
+}
+
+static bool slice_freezer_action_supported_by_children(Unit *s) {
+        Unit *member;
+        int r;
+
+        assert(s);
+
+        UNIT_FOREACH_DEPENDENCY(member, s, UNIT_ATOM_SLICE_OF) {
+
+                if (member->type == UNIT_SLICE) {
+                        r = slice_freezer_action_supported_by_children(member);
+                        if (!r)
+                                return r;
+                }
+
+                if (!UNIT_VTABLE(member)->freeze)
+                        return false;
+        }
+
+        return true;
+}
+
+static int slice_freezer_action(Unit *s, FreezerAction action) {
+        Unit *member;
+        int r;
+
+        assert(s);
+        assert(IN_SET(action, FREEZER_FREEZE, FREEZER_THAW));
+
+        if (action == FREEZER_FREEZE && !slice_freezer_action_supported_by_children(s)) {
+                log_unit_warning(s, "Requested freezer operation is not supported by all children of the slice");
+                return 0;
+        }
+
+        UNIT_FOREACH_DEPENDENCY(member, s, UNIT_ATOM_SLICE_OF) {
+                if (!member->cgroup_realized)
+                        continue;
+
+                if (action == FREEZER_FREEZE)
+                        r = UNIT_VTABLE(member)->freeze(member);
+                else if (UNIT_VTABLE(member)->thaw)
+                        r = UNIT_VTABLE(member)->thaw(member);
+                else
+                        /* Thawing is requested but no corresponding method is available, ignore. */
+                        r = 0;
+                if (r < 0)
+                        return r;
+        }
+
+        return unit_cgroup_freezer_action(s, action);
+}
+
+static int slice_freeze(Unit *s) {
+        assert(s);
+
+        return slice_freezer_action(s, FREEZER_FREEZE);
+}
+
+static int slice_thaw(Unit *s) {
+        assert(s);
+
+        return slice_freezer_action(s, FREEZER_THAW);
+}
+
+static bool slice_can_freeze(Unit *s) {
+        assert(s);
+
+        return slice_freezer_action_supported_by_children(s);
+}
+
+const UnitVTable slice_vtable = {
+        .object_size = sizeof(Slice),
+        .cgroup_context_offset = offsetof(Slice, cgroup_context),
+
+        .sections =
+                "Unit\0"
+                "Slice\0"
+                "Install\0",
+        .private_section = "Slice",
+
+        .can_transient = true,
+        .can_set_managed_oom = true,
+
+        .init = slice_init,
+        .load = slice_load,
+
+        .coldplug = slice_coldplug,
+
+        .dump = slice_dump,
+
+        .start = slice_start,
+        .stop = slice_stop,
+
+        .kill = slice_kill,
+
+        .freeze = slice_freeze,
+        .thaw = slice_thaw,
+        .can_freeze = slice_can_freeze,
+
+        .serialize = slice_serialize,
+        .deserialize_item = slice_deserialize_item,
+
+        .active_state = slice_active_state,
+        .sub_state_to_string = slice_sub_state_to_string,
+
+        .bus_set_property = bus_slice_set_property,
+        .bus_commit_properties = bus_slice_commit_properties,
+
+        .enumerate_perpetual = slice_enumerate_perpetual,
+
+        .status_message_formats = {
+                .finished_start_job = {
+                        [JOB_DONE]       = "Created slice %s.",
+                },
+                .finished_stop_job = {
+                        [JOB_DONE]       = "Removed slice %s.",
+                },
+        },
+};