core: turn on memory/cpu/tasks accounting by default for the root slice

The kernel exposes the necessary data in /proc anyway, let's expose it
hence by default.

With this in place "systemctl status -- -.slice" will show accounting
data out-of-the-box now.

1 files changed, 1 insertions, 0 deletions

diff --git a/src/core/cgroup.h b/src/core/cgroup.h
index 1f50441412..bc8a6951c9 100644
--- a/src/core/cgroup.h
+++ b/src/core/cgroup.h
@@ -208,6 +208,7 @@ int unit_reset_ip_accounting(Unit *u);
         cc ? cc->name : false;                          \
         })
 
+bool manager_owns_root_cgroup(Manager *m);
 bool unit_has_root_cgroup(Unit *u);
 
 int manager_notify_cgroup_empty(Manager *m, const char *group);