nspawn: introduce the new /machine/ tree in the cgroup tree and move containers there

Containers will now carry a label (normally derived from the root
directory name, but configurable by the user), and the container's root
cgroup is /machine/<label>. This label is called "machine name", and can
cover both containers and VMs (as soon as libvirt also makes use of
/machine/).

libsystemd-login can be used to query the machine name from a process.

This patch also includes numerous clean-ups for the cgroup code.

1 files changed, 0 insertions, 5 deletions

diff --git a/src/shared/cgroup-label.c b/src/shared/cgroup-label.c
index a0b486e51e..5b5163c250 100644
--- a/src/shared/cgroup-label.c
+++ b/src/shared/cgroup-label.c
@@ -40,9 +40,6 @@ int cg_create(const char *controller, const char *path, const char *suffix) {
         _cleanup_free_ char *fs = NULL;
         int r;
 
-        assert(controller);
-        assert(path);
-
         r = cg_get_path_and_check(controller, path, suffix, &fs);
         if (r < 0)
                 return r;
@@ -65,8 +62,6 @@ int cg_create(const char *controller, const char *path, const char *suffix) {
 int cg_create_and_attach(const char *controller, const char *path, pid_t pid) {
         int r, q;
 
-        assert(controller);
-        assert(path);
         assert(pid >= 0);
 
         r = cg_create(controller, path, NULL);