cgroup

• kernel doc: cgroup_v1

• [kernel doc: cgroup_v2](https://www.kernel.org/doc/Documentation/cgroup-v2.txt

• Control Groups 解說

• cgroup_subsys_state

struct cgroup {
	/* self css with NULL ->ss, points back to this cgroup */
	struct cgroup_subsys_state self;
 
	unsigned long flags;		/* "unsigned long" so bitops work */
 
	/*
	 * The depth this cgroup is at.  The root is at depth zero and each
	 * step down the hierarchy increments the level.  This along with
	 * ancestors[] can determine whether a given cgroup is a
	 * descendant of another without traversing the hierarchy.
	 */
	int level;
 
	/* Maximum allowed descent tree depth */
	int max_depth;
// ...
	/* Private pointers for each registered subsystem */
	struct cgroup_subsys_state __rcu *subsys[CGROUP_SUBSYS_COUNT];
 
	struct cgroup_root *root;