struct kernfs_node *kn; /* cgroup kernfs entry */
struct kernfs_node *populated_kn; /* kn for "cgroup.subtree_populated" */
- /* the bitmask of subsystems enabled on the child cgroups */
+ /*
+ * The bitmask of subsystems enabled on the child cgroups.
+ * ->subtree_control is the one configured through
+ * "cgroup.subtree_control" while ->child_subsys_mask is the
+ * effective one which may have more subsystems enabled.
+ * Controller knobs are made available iff it's enabled in
+ * ->subtree_control.
+ */
+ unsigned int subtree_control;
unsigned int child_subsys_mask;
/* Private pointers for each registered subsystem */
/* cgroup_root->flags */
enum {
- /*
- * Unfortunately, cgroup core and various controllers are riddled
- * with idiosyncrasies and pointless options. The following flag,
- * when set, will force sane behavior - some options are forced on,
- * others are disallowed, and some controllers will change their
- * hierarchical or other behaviors.
- *
- * The set of behaviors affected by this flag are still being
- * determined and developed and the mount option for this flag is
- * prefixed with __DEVEL__. The prefix will be dropped once we
- * reach the point where all behaviors are compatible with the
- * planned unified hierarchy, which will automatically turn on this
- * flag.
- *
- * The followings are the behaviors currently affected this flag.
- *
- * - Mount options "noprefix", "xattr", "clone_children",
- * "release_agent" and "name" are disallowed.
- *
- * - When mounting an existing superblock, mount options should
- * match.
- *
- * - Remount is disallowed.
- *
- * - rename(2) is disallowed.
- *
- * - "tasks" is removed. Everything should be at process
- * granularity. Use "cgroup.procs" instead.
- *
- * - "cgroup.procs" is not sorted. pids will be unique unless they
- * got recycled inbetween reads.
- *
- * - "release_agent" and "notify_on_release" are removed.
- * Replacement notification mechanism will be implemented.
- *
- * - "cgroup.clone_children" is removed.
- *
- * - "cgroup.subtree_populated" is available. Its value is 0 if
- * the cgroup and its descendants contain no task; otherwise, 1.
- * The file also generates kernfs notification which can be
- * monitored through poll and [di]notify when the value of the
- * file changes.
- *
- * - If mount is requested with sane_behavior but without any
- * subsystem, the default unified hierarchy is mounted.
- *
- * - cpuset: tasks will be kept in empty cpusets when hotplug happens
- * and take masks of ancestors with non-empty cpus/mems, instead of
- * being moved to an ancestor.
- *
- * - cpuset: a task can be moved into an empty cpuset, and again it
- * takes masks of ancestors.
- *
- * - memcg: use_hierarchy is on by default and the cgroup file for
- * the flag is not created.
- *
- * - blkcg: blk-throttle becomes properly hierarchical.
- *
- * - debug: disallowed on the default hierarchy.
- */
- CGRP_ROOT_SANE_BEHAVIOR = (1 << 0),
-
+ CGRP_ROOT_SANE_BEHAVIOR = (1 << 0), /* __DEVEL__sane_behavior specified */
CGRP_ROOT_NOPREFIX = (1 << 1), /* mounted subsystems have no named prefix */
CGRP_ROOT_XATTR = (1 << 2), /* supports extended attributes */
-
- /* mount options live below bit 16 */
- CGRP_ROOT_OPTION_MASK = (1 << 16) - 1,
};
/*
enum {
CFTYPE_ONLY_ON_ROOT = (1 << 0), /* only create on root cgrp */
CFTYPE_NOT_ON_ROOT = (1 << 1), /* don't create on root cgrp */
- CFTYPE_INSANE = (1 << 2), /* don't create if sane_behavior */
CFTYPE_NO_PREFIX = (1 << 3), /* (DON'T USE FOR NEW FILES) no subsys prefix */
- CFTYPE_ONLY_ON_DFL = (1 << 4), /* only on default hierarchy */
+
+ /* internal flags, do not use outside cgroup core proper */
+ __CFTYPE_ONLY_ON_DFL = (1 << 16), /* only on default hierarchy */
+ __CFTYPE_NOT_ON_DFL = (1 << 17), /* not on default hierarchy */
};
#define MAX_CFTYPE_NAME 64
extern struct cgroup_root cgrp_dfl_root;
extern struct css_set init_css_set;
+/**
+ * cgroup_on_dfl - test whether a cgroup is on the default hierarchy
+ * @cgrp: the cgroup of interest
+ *
+ * The default hierarchy is the v2 interface of cgroup and this function
+ * can be used to test whether a cgroup is on the default hierarchy for
+ * cases where a subsystem should behave differnetly depending on the
+ * interface version.
+ *
+ * The set of behaviors which change on the default hierarchy are still
+ * being determined and the mount option is prefixed with __DEVEL__.
+ *
+ * List of changed behaviors:
+ *
+ * - Mount options "noprefix", "xattr", "clone_children", "release_agent"
+ * and "name" are disallowed.
+ *
+ * - When mounting an existing superblock, mount options should match.
+ *
+ * - Remount is disallowed.
+ *
+ * - rename(2) is disallowed.
+ *
+ * - "tasks" is removed. Everything should be at process granularity. Use
+ * "cgroup.procs" instead.
+ *
+ * - "cgroup.procs" is not sorted. pids will be unique unless they got
+ * recycled inbetween reads.
+ *
+ * - "release_agent" and "notify_on_release" are removed. Replacement
+ * notification mechanism will be implemented.
+ *
+ * - "cgroup.clone_children" is removed.
+ *
+ * - "cgroup.subtree_populated" is available. Its value is 0 if the cgroup
+ * and its descendants contain no task; otherwise, 1. The file also
+ * generates kernfs notification which can be monitored through poll and
+ * [di]notify when the value of the file changes.
+ *
+ * - cpuset: tasks will be kept in empty cpusets when hotplug happens and
+ * take masks of ancestors with non-empty cpus/mems, instead of being
+ * moved to an ancestor.
+ *
+ * - cpuset: a task can be moved into an empty cpuset, and again it takes
+ * masks of ancestors.
+ *
+ * - memcg: use_hierarchy is on by default and the cgroup file for the flag
+ * is not created.
+ *
+ * - blkcg: blk-throttle becomes properly hierarchical.
+ *
+ * - debug: disallowed on the default hierarchy.
+ */
static inline bool cgroup_on_dfl(const struct cgroup *cgrp)
{
return cgrp->root == &cgrp_dfl_root;
}
-/*
- * See the comment above CGRP_ROOT_SANE_BEHAVIOR for details. This
- * function can be called as long as @cgrp is accessible.
- */
-static inline bool cgroup_sane_behavior(const struct cgroup *cgrp)
-{
- return cgrp->root->flags & CGRP_ROOT_SANE_BEHAVIOR;
-}
-
/* no synchronization, the result can only be used as a hint */
static inline bool cgroup_has_tasks(struct cgroup *cgrp)
{
char *task_cgroup_path(struct task_struct *task, char *buf, size_t buflen);
-int cgroup_add_cftypes(struct cgroup_subsys *ss, struct cftype *cfts);
+int cgroup_add_dfl_cftypes(struct cgroup_subsys *ss, struct cftype *cfts);
+int cgroup_add_legacy_cftypes(struct cgroup_subsys *ss, struct cftype *cfts);
int cgroup_rm_cftypes(struct cftype *cfts);
bool cgroup_is_descendant(struct cgroup *cgrp, struct cgroup *ancestor);
int (*css_online)(struct cgroup_subsys_state *css);
void (*css_offline)(struct cgroup_subsys_state *css);
void (*css_free)(struct cgroup_subsys_state *css);
+ void (*css_reset)(struct cgroup_subsys_state *css);
int (*can_attach)(struct cgroup_subsys_state *css,
struct cgroup_taskset *tset);
*/
struct list_head cfts;
- /* base cftypes, automatically registered with subsys itself */
- struct cftype *base_cftypes;
+ /*
+ * Base cftypes which are automatically registered. The two can
+ * point to the same array.
+ */
+ struct cftype *dfl_cftypes; /* for the default hierarchy */
+ struct cftype *legacy_cftypes; /* for the legacy hierarchies */
+
+ /*
+ * A subsystem may depend on other subsystems. When such subsystem
+ * is enabled on a cgroup, the depended-upon subsystems are enabled
+ * together if available. Subsystems enabled due to dependency are
+ * not visible to userland until explicitly enabled. The following
+ * specifies the mask of subsystems that this one depends on.
+ */
+ unsigned int depends_on;
};
#define SUBSYS(_x) extern struct cgroup_subsys _x ## _cgrp_subsys;
git.openpandora.org / pandora-kernel.git / blobdiff