+ if (c->memory_accounting ||
+ c->memory_limit != CGROUP_LIMIT_MAX ||
+ cgroup_context_has_unified_memory_config(c))
+ mask |= CGROUP_MASK_MEMORY;
+
+ if (c->device_allow ||
+ c->device_policy != CGROUP_AUTO)
+ mask |= CGROUP_MASK_DEVICES;
+
+ if (c->tasks_accounting ||
+ c->tasks_max != (uint64_t) -1)
+ mask |= CGROUP_MASK_PIDS;
+
+ return mask;
+}
+
+CGroupMask unit_get_own_mask(Unit *u) {
+ CGroupContext *c;
+
+ /* Returns the mask of controllers the unit needs for itself */
+
+ c = unit_get_cgroup_context(u);
+ if (!c)
+ return 0;
+
+ /* If delegation is turned on, then turn on all cgroups,
+ * unless we are on the legacy hierarchy and the process we
+ * fork into it is known to drop privileges, and hence
+ * shouldn't get access to the controllers.
+ *
+ * Note that on the unified hierarchy it is safe to delegate
+ * controllers to unprivileged services. */
+
+ if (c->delegate) {
+ ExecContext *e;
+
+ e = unit_get_exec_context(u);
+ if (!e ||
+ exec_context_maintains_privileges(e) ||
+ cg_all_unified())
+ return _CGROUP_MASK_ALL;
+ }
+
+ return cgroup_context_get_mask(c);
+}
+
+CGroupMask unit_get_members_mask(Unit *u) {
+ assert(u);
+
+ /* Returns the mask of controllers all of the unit's children
+ * require, merged */
+
+ if (u->cgroup_members_mask_valid)
+ return u->cgroup_members_mask;
+
+ u->cgroup_members_mask = 0;
+
+ if (u->type == UNIT_SLICE) {
+ Unit *member;
+ Iterator i;
+
+ SET_FOREACH(member, u->dependencies[UNIT_BEFORE], i) {
+
+ if (member == u)
+ continue;
+
+ if (UNIT_DEREF(member->slice) != u)
+ continue;
+
+ u->cgroup_members_mask |=
+ unit_get_own_mask(member) |
+ unit_get_members_mask(member);
+ }
+ }
+
+ u->cgroup_members_mask_valid = true;
+ return u->cgroup_members_mask;
+}
+
+CGroupMask unit_get_siblings_mask(Unit *u) {
+ assert(u);
+
+ /* Returns the mask of controllers all of the unit's siblings
+ * require, i.e. the members mask of the unit's parent slice
+ * if there is one. */
+
+ if (UNIT_ISSET(u->slice))
+ return unit_get_members_mask(UNIT_DEREF(u->slice));
+
+ return unit_get_own_mask(u) | unit_get_members_mask(u);
+}
+
+CGroupMask unit_get_subtree_mask(Unit *u) {
+
+ /* Returns the mask of this subtree, meaning of the group
+ * itself and its children. */
+
+ return unit_get_own_mask(u) | unit_get_members_mask(u);
+}
+
+CGroupMask unit_get_target_mask(Unit *u) {
+ CGroupMask mask;
+
+ /* This returns the cgroup mask of all controllers to enable
+ * for a specific cgroup, i.e. everything it needs itself,
+ * plus all that its children need, plus all that its siblings
+ * need. This is primarily useful on the legacy cgroup
+ * hierarchy, where we need to duplicate each cgroup in each
+ * hierarchy that shall be enabled for it. */
+
+ mask = unit_get_own_mask(u) | unit_get_members_mask(u) | unit_get_siblings_mask(u);
+ mask &= u->manager->cgroup_supported;
+
+ return mask;
+}
+
+CGroupMask unit_get_enable_mask(Unit *u) {
+ CGroupMask mask;
+
+ /* This returns the cgroup mask of all controllers to enable
+ * for the children of a specific cgroup. This is primarily
+ * useful for the unified cgroup hierarchy, where each cgroup
+ * controls which controllers are enabled for its children. */
+
+ mask = unit_get_members_mask(u);
+ mask &= u->manager->cgroup_supported;
+
+ return mask;
+}
+
+/* Recurse from a unit up through its containing slices, propagating
+ * mask bits upward. A unit is also member of itself. */
+void unit_update_cgroup_members_masks(Unit *u) {
+ CGroupMask m;
+ bool more;
+
+ assert(u);
+
+ /* Calculate subtree mask */
+ m = unit_get_subtree_mask(u);
+
+ /* See if anything changed from the previous invocation. If
+ * not, we're done. */
+ if (u->cgroup_subtree_mask_valid && m == u->cgroup_subtree_mask)
+ return;
+
+ more =
+ u->cgroup_subtree_mask_valid &&
+ ((m & ~u->cgroup_subtree_mask) != 0) &&
+ ((~m & u->cgroup_subtree_mask) == 0);
+
+ u->cgroup_subtree_mask = m;
+ u->cgroup_subtree_mask_valid = true;
+
+ if (UNIT_ISSET(u->slice)) {
+ Unit *s = UNIT_DEREF(u->slice);
+
+ if (more)
+ /* There's more set now than before. We
+ * propagate the new mask to the parent's mask
+ * (not caring if it actually was valid or
+ * not). */
+
+ s->cgroup_members_mask |= m;
+
+ else
+ /* There's less set now than before (or we
+ * don't know), we need to recalculate
+ * everything, so let's invalidate the
+ * parent's members mask */
+
+ s->cgroup_members_mask_valid = false;
+
+ /* And now make sure that this change also hits our
+ * grandparents */
+ unit_update_cgroup_members_masks(s);
+ }
+}
+
+static const char *migrate_callback(CGroupMask mask, void *userdata) {
+ Unit *u = userdata;
+
+ assert(mask != 0);
+ assert(u);
+
+ while (u) {
+ if (u->cgroup_path &&
+ u->cgroup_realized &&
+ (u->cgroup_realized_mask & mask) == mask)
+ return u->cgroup_path;
+
+ u = UNIT_DEREF(u->slice);
+ }
+
+ return NULL;
+}
+
+char *unit_default_cgroup_path(Unit *u) {
+ _cleanup_free_ char *escaped = NULL, *slice = NULL;
+ int r;
+
+ assert(u);
+
+ if (unit_has_name(u, SPECIAL_ROOT_SLICE))
+ return strdup(u->manager->cgroup_root);
+
+ if (UNIT_ISSET(u->slice) && !unit_has_name(UNIT_DEREF(u->slice), SPECIAL_ROOT_SLICE)) {
+ r = cg_slice_to_path(UNIT_DEREF(u->slice)->id, &slice);
+ if (r < 0)
+ return NULL;
+ }
+
+ escaped = cg_escape(u->id);
+ if (!escaped)
+ return NULL;
+
+ if (slice)
+ return strjoin(u->manager->cgroup_root, "/", slice, "/",
+ escaped);
+ else
+ return strjoin(u->manager->cgroup_root, "/", escaped);
+}
+
+int unit_set_cgroup_path(Unit *u, const char *path) {
+ _cleanup_free_ char *p = NULL;
+ int r;
+
+ assert(u);
+
+ if (path) {
+ p = strdup(path);
+ if (!p)
+ return -ENOMEM;
+ } else
+ p = NULL;
+
+ if (streq_ptr(u->cgroup_path, p))
+ return 0;
+
+ if (p) {
+ r = hashmap_put(u->manager->cgroup_unit, p, u);
+ if (r < 0)
+ return r;
+ }
+
+ unit_release_cgroup(u);
+
+ u->cgroup_path = p;
+ p = NULL;
+
+ return 1;
+}
+
+int unit_watch_cgroup(Unit *u) {
+ _cleanup_free_ char *events = NULL;
+ int r;
+
+ assert(u);
+
+ if (!u->cgroup_path)
+ return 0;
+
+ if (u->cgroup_inotify_wd >= 0)
+ return 0;
+
+ /* Only applies to the unified hierarchy */
+ if (!cg_unified(SYSTEMD_CGROUP_CONTROLLER))
+ return 0;
+
+ /* Don't watch the root slice, it's pointless. */
+ if (unit_has_name(u, SPECIAL_ROOT_SLICE))
+ return 0;
+
+ r = hashmap_ensure_allocated(&u->manager->cgroup_inotify_wd_unit, &trivial_hash_ops);
+ if (r < 0)
+ return log_oom();
+
+ r = cg_get_path(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, "cgroup.events", &events);
+ if (r < 0)
+ return log_oom();
+
+ u->cgroup_inotify_wd = inotify_add_watch(u->manager->cgroup_inotify_fd, events, IN_MODIFY);
+ if (u->cgroup_inotify_wd < 0) {
+
+ if (errno == ENOENT) /* If the directory is already
+ * gone we don't need to track
+ * it, so this is not an error */
+ return 0;
+
+ return log_unit_error_errno(u, errno, "Failed to add inotify watch descriptor for control group %s: %m", u->cgroup_path);
+ }
+
+ r = hashmap_put(u->manager->cgroup_inotify_wd_unit, INT_TO_PTR(u->cgroup_inotify_wd), u);
+ if (r < 0)
+ return log_unit_error_errno(u, r, "Failed to add inotify watch descriptor to hash map: %m");
+
+ return 0;
+}
+
+static int unit_create_cgroup(
+ Unit *u,
+ CGroupMask target_mask,
+ CGroupMask enable_mask) {
+
+ CGroupContext *c;
+ int r;
+
+ assert(u);
+
+ c = unit_get_cgroup_context(u);
+ if (!c)
+ return 0;
+
+ if (!u->cgroup_path) {
+ _cleanup_free_ char *path = NULL;
+
+ path = unit_default_cgroup_path(u);
+ if (!path)
+ return log_oom();
+
+ r = unit_set_cgroup_path(u, path);
+ if (r == -EEXIST)
+ return log_unit_error_errno(u, r, "Control group %s exists already.", path);
+ if (r < 0)
+ return log_unit_error_errno(u, r, "Failed to set unit's control group path to %s: %m", path);
+ }
+
+ /* First, create our own group */
+ r = cg_create_everywhere(u->manager->cgroup_supported, target_mask, u->cgroup_path);
+ if (r < 0)
+ return log_unit_error_errno(u, r, "Failed to create cgroup %s: %m", u->cgroup_path);
+
+ /* Start watching it */
+ (void) unit_watch_cgroup(u);
+
+ /* Enable all controllers we need */
+ r = cg_enable_everywhere(u->manager->cgroup_supported, enable_mask, u->cgroup_path);
+ if (r < 0)
+ log_unit_warning_errno(u, r, "Failed to enable controllers on cgroup %s, ignoring: %m", u->cgroup_path);
+
+ /* Keep track that this is now realized */
+ u->cgroup_realized = true;
+ u->cgroup_realized_mask = target_mask;
+ u->cgroup_enabled_mask = enable_mask;
+
+ if (u->type != UNIT_SLICE && !c->delegate) {
+
+ /* Then, possibly move things over, but not if
+ * subgroups may contain processes, which is the case
+ * for slice and delegation units. */
+ r = cg_migrate_everywhere(u->manager->cgroup_supported, u->cgroup_path, u->cgroup_path, migrate_callback, u);
+ if (r < 0)
+ log_unit_warning_errno(u, r, "Failed to migrate cgroup from to %s, ignoring: %m", u->cgroup_path);
+ }
+
+ return 0;
+}
+
+int unit_attach_pids_to_cgroup(Unit *u) {
+ int r;
+ assert(u);
+
+ r = unit_realize_cgroup(u);
+ if (r < 0)
+ return r;
+
+ r = cg_attach_many_everywhere(u->manager->cgroup_supported, u->cgroup_path, u->pids, migrate_callback, u);
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+static void cgroup_xattr_apply(Unit *u) {
+ char ids[SD_ID128_STRING_MAX];
+ int r;
+
+ assert(u);
+
+ if (!MANAGER_IS_SYSTEM(u->manager))
+ return;
+
+ if (sd_id128_is_null(u->invocation_id))
+ return;
+
+ r = cg_set_xattr(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path,
+ "trusted.invocation_id",
+ sd_id128_to_string(u->invocation_id, ids), 32,
+ 0);
+ if (r < 0)
+ log_unit_warning_errno(u, r, "Failed to set invocation ID on control group %s, ignoring: %m", u->cgroup_path);
+}
+
+static bool unit_has_mask_realized(Unit *u, CGroupMask target_mask, CGroupMask enable_mask) {
+ assert(u);
+
+ return u->cgroup_realized && u->cgroup_realized_mask == target_mask && u->cgroup_enabled_mask == enable_mask;
+}
+
+/* Check if necessary controllers and attributes for a unit are in place.
+ *
+ * If so, do nothing.
+ * If not, create paths, move processes over, and set attributes.
+ *
+ * Returns 0 on success and < 0 on failure. */
+static int unit_realize_cgroup_now(Unit *u, ManagerState state) {
+ CGroupMask target_mask, enable_mask;
+ int r;
+
+ assert(u);
+
+ if (u->in_cgroup_queue) {
+ LIST_REMOVE(cgroup_queue, u->manager->cgroup_queue, u);
+ u->in_cgroup_queue = false;
+ }
+
+ target_mask = unit_get_target_mask(u);
+ enable_mask = unit_get_enable_mask(u);
+
+ if (unit_has_mask_realized(u, target_mask, enable_mask))
+ return 0;
+
+ /* First, realize parents */
+ if (UNIT_ISSET(u->slice)) {
+ r = unit_realize_cgroup_now(UNIT_DEREF(u->slice), state);
+ if (r < 0)
+ return r;
+ }
+
+ /* And then do the real work */
+ r = unit_create_cgroup(u, target_mask, enable_mask);
+ if (r < 0)
+ return r;
+
+ /* Finally, apply the necessary attributes. */
+ cgroup_context_apply(u, target_mask, state);
+ cgroup_xattr_apply(u);
+
+ return 0;
+}
+
+static void unit_add_to_cgroup_queue(Unit *u) {
+
+ if (u->in_cgroup_queue)
+ return;
+
+ LIST_PREPEND(cgroup_queue, u->manager->cgroup_queue, u);
+ u->in_cgroup_queue = true;
+}
+
+unsigned manager_dispatch_cgroup_queue(Manager *m) {
+ ManagerState state;
+ unsigned n = 0;
+ Unit *i;
+ int r;
+
+ state = manager_state(m);
+
+ while ((i = m->cgroup_queue)) {
+ assert(i->in_cgroup_queue);
+
+ r = unit_realize_cgroup_now(i, state);
+ if (r < 0)
+ log_warning_errno(r, "Failed to realize cgroups for queued unit %s, ignoring: %m", i->id);
+
+ n++;
+ }
+
+ return n;
+}
+
+static void unit_queue_siblings(Unit *u) {
+ Unit *slice;
+
+ /* This adds the siblings of the specified unit and the
+ * siblings of all parent units to the cgroup queue. (But
+ * neither the specified unit itself nor the parents.) */
+
+ while ((slice = UNIT_DEREF(u->slice))) {
+ Iterator i;
+ Unit *m;
+
+ SET_FOREACH(m, slice->dependencies[UNIT_BEFORE], i) {
+ if (m == u)
+ continue;
+
+ /* Skip units that have a dependency on the slice
+ * but aren't actually in it. */
+ if (UNIT_DEREF(m->slice) != slice)
+ continue;
+
+ /* No point in doing cgroup application for units
+ * without active processes. */
+ if (UNIT_IS_INACTIVE_OR_FAILED(unit_active_state(m)))
+ continue;
+
+ /* If the unit doesn't need any new controllers
+ * and has current ones realized, it doesn't need
+ * any changes. */
+ if (unit_has_mask_realized(m, unit_get_target_mask(m), unit_get_enable_mask(m)))
+ continue;
+
+ unit_add_to_cgroup_queue(m);
+ }
+
+ u = slice;
+ }
+}
+
+int unit_realize_cgroup(Unit *u) {
+ assert(u);
+
+ if (!UNIT_HAS_CGROUP_CONTEXT(u))
+ return 0;
+
+ /* So, here's the deal: when realizing the cgroups for this
+ * unit, we need to first create all parents, but there's more
+ * actually: for the weight-based controllers we also need to
+ * make sure that all our siblings (i.e. units that are in the
+ * same slice as we are) have cgroups, too. Otherwise, things
+ * would become very uneven as each of their processes would
+ * get as much resources as all our group together. This call
+ * will synchronously create the parent cgroups, but will
+ * defer work on the siblings to the next event loop
+ * iteration. */
+
+ /* Add all sibling slices to the cgroup queue. */
+ unit_queue_siblings(u);
+
+ /* And realize this one now (and apply the values) */
+ return unit_realize_cgroup_now(u, manager_state(u->manager));
+}
+
+void unit_release_cgroup(Unit *u) {
+ assert(u);
+
+ /* Forgets all cgroup details for this cgroup */
+
+ if (u->cgroup_path) {
+ (void) hashmap_remove(u->manager->cgroup_unit, u->cgroup_path);
+ u->cgroup_path = mfree(u->cgroup_path);
+ }
+
+ if (u->cgroup_inotify_wd >= 0) {
+ if (inotify_rm_watch(u->manager->cgroup_inotify_fd, u->cgroup_inotify_wd) < 0)
+ log_unit_debug_errno(u, errno, "Failed to remove cgroup inotify watch %i for %s, ignoring", u->cgroup_inotify_wd, u->id);
+
+ (void) hashmap_remove(u->manager->cgroup_inotify_wd_unit, INT_TO_PTR(u->cgroup_inotify_wd));
+ u->cgroup_inotify_wd = -1;
+ }
+}
+
+void unit_prune_cgroup(Unit *u) {
+ int r;
+ bool is_root_slice;
+
+ assert(u);
+
+ /* Removes the cgroup, if empty and possible, and stops watching it. */
+
+ if (!u->cgroup_path)
+ return;
+
+ (void) unit_get_cpu_usage(u, NULL); /* Cache the last CPU usage value before we destroy the cgroup */
+
+ is_root_slice = unit_has_name(u, SPECIAL_ROOT_SLICE);
+
+ r = cg_trim_everywhere(u->manager->cgroup_supported, u->cgroup_path, !is_root_slice);
+ if (r < 0) {
+ log_unit_debug_errno(u, r, "Failed to destroy cgroup %s, ignoring: %m", u->cgroup_path);
+ return;
+ }
+
+ if (is_root_slice)
+ return;
+
+ unit_release_cgroup(u);
+
+ u->cgroup_realized = false;
+ u->cgroup_realized_mask = 0;
+ u->cgroup_enabled_mask = 0;
+}
+
+int unit_search_main_pid(Unit *u, pid_t *ret) {
+ _cleanup_fclose_ FILE *f = NULL;
+ pid_t pid = 0, npid, mypid;
+ int r;
+
+ assert(u);
+ assert(ret);
+
+ if (!u->cgroup_path)
+ return -ENXIO;
+
+ r = cg_enumerate_processes(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, &f);
+ if (r < 0)
+ return r;
+
+ mypid = getpid();
+ while (cg_read_pid(f, &npid) > 0) {
+ pid_t ppid;
+
+ if (npid == pid)
+ continue;
+
+ /* Ignore processes that aren't our kids */
+ if (get_process_ppid(npid, &ppid) >= 0 && ppid != mypid)
+ continue;
+
+ if (pid != 0)
+ /* Dang, there's more than one daemonized PID
+ in this group, so we don't know what process
+ is the main process. */
+
+ return -ENODATA;
+
+ pid = npid;
+ }
+
+ *ret = pid;
+ return 0;
+}
+
+static int unit_watch_pids_in_path(Unit *u, const char *path) {
+ _cleanup_closedir_ DIR *d = NULL;
+ _cleanup_fclose_ FILE *f = NULL;
+ int ret = 0, r;
+
+ assert(u);
+ assert(path);
+
+ r = cg_enumerate_processes(SYSTEMD_CGROUP_CONTROLLER, path, &f);
+ if (r < 0)
+ ret = r;
+ else {
+ pid_t pid;
+
+ while ((r = cg_read_pid(f, &pid)) > 0) {
+ r = unit_watch_pid(u, pid);
+ if (r < 0 && ret >= 0)
+ ret = r;
+ }
+
+ if (r < 0 && ret >= 0)
+ ret = r;
+ }
+
+ r = cg_enumerate_subgroups(SYSTEMD_CGROUP_CONTROLLER, path, &d);
+ if (r < 0) {
+ if (ret >= 0)
+ ret = r;
+ } else {
+ char *fn;
+
+ while ((r = cg_read_subgroup(d, &fn)) > 0) {
+ _cleanup_free_ char *p = NULL;
+
+ p = strjoin(path, "/", fn);
+ free(fn);
+
+ if (!p)
+ return -ENOMEM;
+
+ r = unit_watch_pids_in_path(u, p);
+ if (r < 0 && ret >= 0)
+ ret = r;
+ }
+
+ if (r < 0 && ret >= 0)
+ ret = r;
+ }
+
+ return ret;
+}
+
+int unit_watch_all_pids(Unit *u) {
+ assert(u);
+
+ /* Adds all PIDs from our cgroup to the set of PIDs we
+ * watch. This is a fallback logic for cases where we do not
+ * get reliable cgroup empty notifications: we try to use
+ * SIGCHLD as replacement. */
+
+ if (!u->cgroup_path)
+ return -ENOENT;
+
+ if (cg_unified(SYSTEMD_CGROUP_CONTROLLER)) /* On unified we can use proper notifications */
+ return 0;
+
+ return unit_watch_pids_in_path(u, u->cgroup_path);
+}
+
+int unit_notify_cgroup_empty(Unit *u) {
+ int r;
+
+ assert(u);
+
+ if (!u->cgroup_path)
+ return 0;
+
+ r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path);
+ if (r <= 0)
+ return r;
+
+ unit_add_to_gc_queue(u);
+
+ if (UNIT_VTABLE(u)->notify_cgroup_empty)
+ UNIT_VTABLE(u)->notify_cgroup_empty(u);
+
+ return 0;
+}
+
+static int on_cgroup_inotify_event(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
+ Manager *m = userdata;
+
+ assert(s);
+ assert(fd >= 0);
+ assert(m);
+
+ for (;;) {
+ union inotify_event_buffer buffer;
+ struct inotify_event *e;
+ ssize_t l;
+
+ l = read(fd, &buffer, sizeof(buffer));
+ if (l < 0) {
+ if (errno == EINTR || errno == EAGAIN)
+ return 0;
+
+ return log_error_errno(errno, "Failed to read control group inotify events: %m");
+ }
+
+ FOREACH_INOTIFY_EVENT(e, buffer, l) {
+ Unit *u;
+
+ if (e->wd < 0)
+ /* Queue overflow has no watch descriptor */
+ continue;
+
+ if (e->mask & IN_IGNORED)
+ /* The watch was just removed */
+ continue;
+
+ u = hashmap_get(m->cgroup_inotify_wd_unit, INT_TO_PTR(e->wd));
+ if (!u) /* Not that inotify might deliver
+ * events for a watch even after it
+ * was removed, because it was queued
+ * before the removal. Let's ignore
+ * this here safely. */
+ continue;
+
+ (void) unit_notify_cgroup_empty(u);
+ }
+ }
+}
+#endif // 0
+
+int manager_setup_cgroup(Manager *m) {
+ _cleanup_free_ char *path = NULL;
+ CGroupController c;
+ int r;
+ char *e;
+
+ assert(m);
+
+ /* 1. Determine hierarchy */
+ m->cgroup_root = mfree(m->cgroup_root);
+ r = cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, 0, &m->cgroup_root);
+ if (r < 0)
+ return log_error_errno(r, "Cannot determine cgroup we are running in: %m");
+
+#if 0 /// elogind does not support systemd scopes and slices
+ /* Chop off the init scope, if we are already located in it */
+ e = endswith(m->cgroup_root, "/" SPECIAL_INIT_SCOPE);
+
+ /* LEGACY: Also chop off the system slice if we are in
+ * it. This is to support live upgrades from older systemd
+ * versions where PID 1 was moved there. Also see
+ * cg_get_root_path(). */
+ if (!e && MANAGER_IS_SYSTEM(m)) {
+ e = endswith(m->cgroup_root, "/" SPECIAL_SYSTEM_SLICE);
+ if (!e)
+ e = endswith(m->cgroup_root, "/system"); /* even more legacy */
+ }
+ if (e)
+ *e = 0;
+#endif // 0
+
+ /* And make sure to store away the root value without trailing
+ * slash, even for the root dir, so that we can easily prepend
+ * it everywhere. */
+ while ((e = endswith(m->cgroup_root, "/")))
+ *e = 0;
+ log_debug_elogind("Cgroup Controller \"%s\" -> root \"%s\"",
+ SYSTEMD_CGROUP_CONTROLLER, m->cgroup_root);
+
+ /* 2. Show data */
+ r = cg_get_path(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_root, NULL, &path);
+ if (r < 0)
+ return log_error_errno(r, "Cannot find cgroup mount point: %m");
+
+ r = cg_unified_flush();
+ if (r < 0)
+ return log_error_errno(r, "Couldn't determine if we are running in the unified hierarchy: %m");
+
+ if (cg_all_unified())
+ log_debug("Unified cgroup hierarchy is located at %s.", path);
+ else if (cg_unified(SYSTEMD_CGROUP_CONTROLLER))
+ log_debug("Unified cgroup hierarchy is located at %s. Controllers are on legacy hierarchies.", path);
+ else
+ log_debug("Using cgroup controller " SYSTEMD_CGROUP_CONTROLLER ". File system hierarchy is at %s.", path);
+
+ if (!m->test_run) {
+ const char *scope_path;
+
+ /* 3. Install agent */
+ if (cg_unified(SYSTEMD_CGROUP_CONTROLLER)) {
+
+ /* In the unified hierarchy we can get
+ * cgroup empty notifications via inotify. */
+
+#if 0 /// elogind does not support the unified hierarchy, yet.
+ m->cgroup_inotify_event_source = sd_event_source_unref(m->cgroup_inotify_event_source);
+ safe_close(m->cgroup_inotify_fd);
+
+ m->cgroup_inotify_fd = inotify_init1(IN_NONBLOCK|IN_CLOEXEC);
+ if (m->cgroup_inotify_fd < 0)
+ return log_error_errno(errno, "Failed to create control group inotify object: %m");
+
+ r = sd_event_add_io(m->event, &m->cgroup_inotify_event_source, m->cgroup_inotify_fd, EPOLLIN, on_cgroup_inotify_event, m);
+ if (r < 0)
+ return log_error_errno(r, "Failed to watch control group inotify object: %m");
+
+ /* Process cgroup empty notifications early, but after service notifications and SIGCHLD. Also
+ * see handling of cgroup agent notifications, for the classic cgroup hierarchy support. */
+ r = sd_event_source_set_priority(m->cgroup_inotify_event_source, SD_EVENT_PRIORITY_NORMAL-5);
+ if (r < 0)
+ return log_error_errno(r, "Failed to set priority of inotify event source: %m");
+
+ (void) sd_event_source_set_description(m->cgroup_inotify_event_source, "cgroup-inotify");
+
+#else
+ return log_error_errno(EOPNOTSUPP, "Unified cgroup hierarchy not supported: %m");
+#endif // 0
+ } else if (MANAGER_IS_SYSTEM(m)) {
+
+ /* On the legacy hierarchy we only get
+ * notifications via cgroup agents. (Which
+ * isn't really reliable, since it does not
+ * generate events when control groups with
+ * children run empty. */
+
+ r = cg_install_release_agent(SYSTEMD_CGROUP_CONTROLLER, SYSTEMD_CGROUP_AGENT_PATH);
+ if (r < 0)
+ log_warning_errno(r, "Failed to install release agent, ignoring: %m");
+ else if (r > 0)
+ log_debug("Installed release agent.");
+ else if (r == 0)
+ log_debug("Release agent already installed.");
+ }
+
+#if 0 /// elogind is not meant to run in systemd init scope
+ /* 4. Make sure we are in the special "init.scope" unit in the root slice. */
+ scope_path = strjoina(m->cgroup_root, "/" SPECIAL_INIT_SCOPE);
+ r = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, scope_path, 0);
+#else
+ if (streq(SYSTEMD_CGROUP_CONTROLLER, "name=elogind"))
+ // we are our own cgroup controller
+ scope_path = strjoina("");
+ else if (streq(m->cgroup_root, "/elogind"))
+ // root already is our cgroup
+ scope_path = strjoina(m->cgroup_root);
+ else
+ // we have to create our own group
+ scope_path = strjoina(m->cgroup_root, "/elogind");
+ r = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, scope_path, 0);
+#endif // 0
+ if (r < 0)
+ return log_error_errno(r, "Failed to create %s control group: %m", scope_path);
+ log_debug_elogind("Created control group \"%s\"", scope_path);
+
+ /* also, move all other userspace processes remaining
+ * in the root cgroup into that scope. */
+ r = cg_migrate(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_root, SYSTEMD_CGROUP_CONTROLLER, scope_path, 0);
+ if (r < 0)
+ log_warning_errno(r, "Couldn't move remaining userspace processes, ignoring: %m");
+
+ /* 5. And pin it, so that it cannot be unmounted */
+ safe_close(m->pin_cgroupfs_fd);
+ m->pin_cgroupfs_fd = open(path, O_RDONLY|O_CLOEXEC|O_DIRECTORY|O_NOCTTY|O_NONBLOCK);
+ if (m->pin_cgroupfs_fd < 0)
+ return log_error_errno(errno, "Failed to open pin file: %m");
+
+ /* 6. Always enable hierarchical support if it exists... */
+ if (!cg_all_unified())
+ (void) cg_set_attribute("memory", "/", "memory.use_hierarchy", "1");
+ }
+
+ /* 7. Figure out which controllers are supported */
+ r = cg_mask_supported(&m->cgroup_supported);
+ if (r < 0)
+ return log_error_errno(r, "Failed to determine supported controllers: %m");
+
+ for (c = 0; c < _CGROUP_CONTROLLER_MAX; c++)
+ log_debug("Controller '%s' supported: %s", cgroup_controller_to_string(c), yes_no(m->cgroup_supported & CGROUP_CONTROLLER_TO_MASK(c)));
+
+ return 0;
+}
+
+void manager_shutdown_cgroup(Manager *m, bool delete) {
+ assert(m);
+
+ /* We can't really delete the group, since we are in it. But
+ * let's trim it. */
+ if (delete && m->cgroup_root)
+ (void) cg_trim(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_root, false);
+
+#if 0 /// elogind does not support the unified hierarchy, yet.
+ m->cgroup_inotify_wd_unit = hashmap_free(m->cgroup_inotify_wd_unit);
+
+ m->cgroup_inotify_event_source = sd_event_source_unref(m->cgroup_inotify_event_source);
+ m->cgroup_inotify_fd = safe_close(m->cgroup_inotify_fd);
+#endif // 0
+
+ m->pin_cgroupfs_fd = safe_close(m->pin_cgroupfs_fd);
+
+ m->cgroup_root = mfree(m->cgroup_root);
+}
+
+#if 0 /// UNNEEDED by elogind
+Unit* manager_get_unit_by_cgroup(Manager *m, const char *cgroup) {
+ char *p;
+ Unit *u;
+
+ assert(m);
+ assert(cgroup);
+
+ u = hashmap_get(m->cgroup_unit, cgroup);
+ if (u)
+ return u;
+
+ p = strdupa(cgroup);
+ for (;;) {
+ char *e;
+
+ e = strrchr(p, '/');
+ if (!e || e == p)
+ return hashmap_get(m->cgroup_unit, SPECIAL_ROOT_SLICE);
+
+ *e = 0;
+
+ u = hashmap_get(m->cgroup_unit, p);
+ if (u)
+ return u;
+ }
+}
+
+Unit *manager_get_unit_by_pid_cgroup(Manager *m, pid_t pid) {
+ _cleanup_free_ char *cgroup = NULL;
+ int r;
+
+ assert(m);
+
+ if (pid <= 0)
+ return NULL;
+
+ r = cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, pid, &cgroup);
+ if (r < 0)
+ return NULL;
+
+ return manager_get_unit_by_cgroup(m, cgroup);
+}
+
+Unit *manager_get_unit_by_pid(Manager *m, pid_t pid) {
+ Unit *u;
+
+ assert(m);
+
+ if (pid <= 0)
+ return NULL;
+
+ if (pid == 1)
+ return hashmap_get(m->units, SPECIAL_INIT_SCOPE);
+
+ u = hashmap_get(m->watch_pids1, PID_TO_PTR(pid));
+ if (u)
+ return u;
+
+ u = hashmap_get(m->watch_pids2, PID_TO_PTR(pid));
+ if (u)
+ return u;
+
+ return manager_get_unit_by_pid_cgroup(m, pid);
+}
+#endif // 0
+
+#if 0 /// elogind must substitute this with its own variant
+int manager_notify_cgroup_empty(Manager *m, const char *cgroup) {
+ Unit *u;
+
+ assert(m);
+ assert(cgroup);
+
+ log_debug("Got cgroup empty notification for: %s", cgroup);
+
+ u = manager_get_unit_by_cgroup(m, cgroup);
+ if (!u)
+ return 0;
+
+ return unit_notify_cgroup_empty(u);
+}
+#else
+int manager_notify_cgroup_empty(Manager *m, const char *cgroup) {
+ Session *s;
+
+ assert(m);
+ assert(cgroup);
+
+ log_debug("Got cgroup empty notification for: %s", cgroup);
+
+ s = hashmap_get(m->sessions, cgroup);
+
+ if (s) {
+ session_finalize(s);
+ session_free(s);
+ } else
+ log_warning("Session not found: %s", cgroup);
+
+ return 0;
+}
+#endif // 0
+#if 0 /// UNNEEDED by elogind
+int unit_get_memory_current(Unit *u, uint64_t *ret) {
+ _cleanup_free_ char *v = NULL;
+ int r;
+
+ assert(u);
+ assert(ret);
+
+ if (!u->cgroup_path)
+ return -ENODATA;
+
+ if ((u->cgroup_realized_mask & CGROUP_MASK_MEMORY) == 0)
+ return -ENODATA;
+
+ if (!cg_all_unified())
+ r = cg_get_attribute("memory", u->cgroup_path, "memory.usage_in_bytes", &v);
+ else
+ r = cg_get_attribute("memory", u->cgroup_path, "memory.current", &v);
+ if (r == -ENOENT)
+ return -ENODATA;
+ if (r < 0)
+ return r;
+
+ return safe_atou64(v, ret);
+}
+
+int unit_get_tasks_current(Unit *u, uint64_t *ret) {
+ _cleanup_free_ char *v = NULL;
+ int r;
+
+ assert(u);
+ assert(ret);
+
+ if (!u->cgroup_path)
+ return -ENODATA;
+
+ if ((u->cgroup_realized_mask & CGROUP_MASK_PIDS) == 0)
+ return -ENODATA;
+
+ r = cg_get_attribute("pids", u->cgroup_path, "pids.current", &v);
+ if (r == -ENOENT)
+ return -ENODATA;
+ if (r < 0)
+ return r;
+
+ return safe_atou64(v, ret);
+}
+
+static int unit_get_cpu_usage_raw(Unit *u, nsec_t *ret) {
+ _cleanup_free_ char *v = NULL;
+ uint64_t ns;
+ int r;
+
+ assert(u);
+ assert(ret);
+
+ if (!u->cgroup_path)
+ return -ENODATA;
+
+ if (cg_all_unified()) {
+ const char *keys[] = { "usage_usec", NULL };
+ _cleanup_free_ char *val = NULL;
+ uint64_t us;
+
+ if ((u->cgroup_realized_mask & CGROUP_MASK_CPU) == 0)
+ return -ENODATA;
+
+ r = cg_get_keyed_attribute("cpu", u->cgroup_path, "cpu.stat", keys, &val);
+ if (r < 0)
+ return r;
+
+ r = safe_atou64(val, &us);
+ if (r < 0)
+ return r;
+
+ ns = us * NSEC_PER_USEC;
+ } else {
+ if ((u->cgroup_realized_mask & CGROUP_MASK_CPUACCT) == 0)
+ return -ENODATA;
+
+ r = cg_get_attribute("cpuacct", u->cgroup_path, "cpuacct.usage", &v);
+ if (r == -ENOENT)
+ return -ENODATA;
+ if (r < 0)
+ return r;
+
+ r = safe_atou64(v, &ns);
+ if (r < 0)
+ return r;
+ }
+
+ *ret = ns;
+ return 0;
+}
+
+int unit_get_cpu_usage(Unit *u, nsec_t *ret) {
+ nsec_t ns;
+ int r;
+
+ assert(u);
+
+ /* Retrieve the current CPU usage counter. This will subtract the CPU counter taken when the unit was
+ * started. If the cgroup has been removed already, returns the last cached value. To cache the value, simply
+ * call this function with a NULL return value. */
+
+ r = unit_get_cpu_usage_raw(u, &ns);
+ if (r == -ENODATA && u->cpu_usage_last != NSEC_INFINITY) {
+ /* If we can't get the CPU usage anymore (because the cgroup was already removed, for example), use our
+ * cached value. */
+
+ if (ret)
+ *ret = u->cpu_usage_last;
+ return 0;
+ }
+ if (r < 0)
+ return r;
+
+ if (ns > u->cpu_usage_base)
+ ns -= u->cpu_usage_base;
+ else
+ ns = 0;
+
+ u->cpu_usage_last = ns;
+ if (ret)
+ *ret = ns;
+
+ return 0;
+}
+
+int unit_reset_cpu_usage(Unit *u) {
+ nsec_t ns;
+ int r;
+
+ assert(u);
+
+ u->cpu_usage_last = NSEC_INFINITY;
+
+ r = unit_get_cpu_usage_raw(u, &ns);
+ if (r < 0) {
+ u->cpu_usage_base = 0;
+ return r;
+ }
+
+ u->cpu_usage_base = ns;
+ return 0;
+}
+
+bool unit_cgroup_delegate(Unit *u) {
+ CGroupContext *c;
+
+ assert(u);
+
+ c = unit_get_cgroup_context(u);
+ if (!c)
+ return false;
+
+ return c->delegate;
+}
+
+void unit_invalidate_cgroup(Unit *u, CGroupMask m) {
+ assert(u);
+
+ if (!UNIT_HAS_CGROUP_CONTEXT(u))
+ return;
+
+ if (m == 0)
+ return;
+
+ /* always invalidate compat pairs together */
+ if (m & (CGROUP_MASK_IO | CGROUP_MASK_BLKIO))
+ m |= CGROUP_MASK_IO | CGROUP_MASK_BLKIO;
+
+ if ((u->cgroup_realized_mask & m) == 0)
+ return;
+
+ u->cgroup_realized_mask &= ~m;
+ unit_add_to_cgroup_queue(u);
+}
+
+void manager_invalidate_startup_units(Manager *m) {
+ Iterator i;
+ Unit *u;
+
+ assert(m);
+
+ SET_FOREACH(u, m->startup_units, i)
+ unit_invalidate_cgroup(u, CGROUP_MASK_CPU|CGROUP_MASK_IO|CGROUP_MASK_BLKIO);
+}
+
+static const char* const cgroup_device_policy_table[_CGROUP_DEVICE_POLICY_MAX] = {
+ [CGROUP_AUTO] = "auto",
+ [CGROUP_CLOSED] = "closed",
+ [CGROUP_STRICT] = "strict",
+};
+
+DEFINE_STRING_TABLE_LOOKUP(cgroup_device_policy, CGroupDevicePolicy);
+#endif // 0