Struct cgroups_rs::Cgroup

pub struct Cgroup { /* private fields */ }

A control group is the central structure to this crate.

What are control groups?

Lifting over from the Linux kernel sources:

Control Groups provide a mechanism for aggregating/partitioning sets of tasks, and all their future children, into hierarchical groups with specialized behaviour.

This crate is an attempt at providing a Rust-native way of managing these cgroups.

Implementations

impl Cgroup

pub fn v2(&self) -> bool

pub fn new<P: AsRef<Path>>(hier: Box<dyn Hierarchy>, path: P) -> Result<Cgroup>

Create a new control group in the hierarchy hier, with name path.

Returns a handle to the control group that can be used to manipulate it.

pub fn new_with_specified_controllers<P: AsRef<Path>>(
    hier: Box<dyn Hierarchy>,
    path: P,
    specified_controllers: Option<Vec<String>>
) -> Result<Cgroup>

Create a new control group in the hierarchy hier, with name path.

Returns a handle to the control group that can be used to manipulate it.

pub fn new_with_relative_paths<P: AsRef<Path>>(
    hier: Box<dyn Hierarchy>,
    path: P,
    relative_paths: HashMap<String, String>
) -> Result<Cgroup>

Create a new control group in the hierarchy hier, with name path and relative_paths

Returns a handle to the control group that can be used to manipulate it.

Note that this method is only meaningful for cgroup v1, call it is equivalent to call new in the v2 mode.

pub fn load<P: AsRef<Path>>(hier: Box<dyn Hierarchy>, path: P) -> Cgroup

Create a handle for a control group in the hierarchy hier, with name path.

Returns a handle to the control group (that possibly does not exist until create() has been called on the cgroup.

pub fn load_with_specified_controllers<P: AsRef<Path>>(
    hier: Box<dyn Hierarchy>,
    path: P,
    specified_controllers: Vec<String>
) -> Cgroup

Create a handle for a specified control group in the hierarchy hier, with name path.

Returns a handle to the control group (that possibly does not exist until create() has been called on the cgroup.

pub fn load_with_relative_paths<P: AsRef<Path>>(
    hier: Box<dyn Hierarchy>,
    path: P,
    relative_paths: HashMap<String, String>
) -> Cgroup

Create a handle for a control group in the hierarchy hier, with name path and relative_paths

Returns a handle to the control group (that possibly does not exist until create() has been called on the cgroup.

Note that this method is only meaningful for cgroup v1, call it is equivalent to call load in the v2 mode

pub fn subsystems(&self) -> &Vec<Subsystem>

The list of subsystems that this control group supports.

pub fn delete(&self) -> Result<()>

Deletes the control group.

Note that this function makes no effort in cleaning up the descendant and the underlying system call will fail if there are any descendants. Thus, one should check whether it was actually removed, and remove the descendants first if not. In the future, this behavior will change.

pub fn apply(&self, res: &Resources) -> Result<()>

Apply a set of resource limits to the control group.

pub fn controller_of<'a, T>(&'a self) -> Option<&'a T>where
    &'a T: From<&'a Subsystem>,
    T: Controller + ControllIdentifier,

Retrieve a container based on type inference.

Example:

let pids: &PidController = control_group.controller_of()
                            .expect("No pids controller attached!");
let cpu: &CpuController = control_group.controller_of()
                            .expect("No cpu controller attached!");

pub fn remove_task_by_tgid(&self, tgid: CgroupPid) -> Result<()>

Removes tasks from the control group by thread group id.

Note that this means that the task will be moved back to the root control group in the hierarchy and any rules applied to that control group will still apply to the proc.

pub fn remove_task(&self, tid: CgroupPid) -> Result<()>

Removes a task from the control group.

Note that this means that the task will be moved back to the root control group in the hierarchy and any rules applied to that control group will still apply to the task.

pub fn move_task_to_parent_by_tgid(&self, tgid: CgroupPid) -> Result<()>

Moves tasks to the parent control group by thread group id.

pub fn move_task_to_parent(&self, tid: CgroupPid) -> Result<()>

Moves a task to the parent control group.

pub fn parent_control_group(&self) -> Cgroup

Return a handle to the parent control group in the hierarchy.

pub fn kill(&self) -> Result<()>

Kill every process in the control group. Only supported for v2 cgroups and on kernels 5.14+. This will fail with InvalidOperation if the ‘cgroup.kill’ file does not exist.

pub fn add_task(&self, tid: CgroupPid) -> Result<()>

Attach a task to the control group.

pub fn add_task_by_tgid(&self, tgid: CgroupPid) -> Result<()>

Attach tasks to the control group by thread group id.

pub fn set_cgroup_type(&self, cgroup_type: &str) -> Result<()>

set cgroup.type

pub fn get_cgroup_type(&self) -> Result<String>

get cgroup.type

pub fn set_notify_on_release(&self, enable: bool) -> Result<()>

Set notify_on_release to the control group.

pub fn set_release_agent(&self, path: &str) -> Result<()>

Set release_agent

pub fn procs(&self) -> Vec<CgroupPid>

Returns an Iterator that can be used to iterate over the procs that are currently in the control group.

pub fn tasks(&self) -> Vec<CgroupPid>

Returns an Iterator that can be used to iterate over the tasks that are currently in the control group.

Trait Implementations

impl Clone for Cgroup

fn clone(&self) -> Self

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Cgroup

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Cgroup

fn default() -> Self

Returns the “default value” for a type.