Struct CgroupSysctl 

pub struct CgroupSysctl { /* private fields */ }

A program used to watch for sysctl changes.

CgroupSysctl programs can be attached to a cgroup and will be called every time a process inside that cgroup tries to read from or write to a sysctl knob in proc.

Minimum kernel version

The minimum kernel version required to use this feature is 5.2.

Examples

use std::fs::File;
use aya::programs::{CgroupAttachMode, CgroupSysctl};

let file = File::open("/sys/fs/cgroup/unified")?;
let program: &mut CgroupSysctl = bpf.program_mut("cgroup_sysctl").unwrap().try_into()?;
program.load()?;
program.attach(file, CgroupAttachMode::Single)?;

Implementations

impl CgroupSysctl

pub const PROGRAM_TYPE: ProgramType = ProgramType::CgroupSysctl

The type of the program according to the kernel.

pub fn load(&mut self) -> Result<(), ProgramError>

Loads the program inside the kernel.

pub fn attach<T: AsFd>( &mut self, cgroup: T, mode: CgroupAttachMode, ) -> Result<CgroupSysctlLinkId, ProgramError>

Attaches the program to the given cgroup.

The returned value can be used to detach, see CgroupSysctl::detach.

impl CgroupSysctl

pub fn detach( &mut self, link_id: CgroupSysctlLinkId, ) -> Result<(), ProgramError>

Detaches the program.

See Self::attach.

pub fn take_link( &mut self, link_id: CgroupSysctlLinkId, ) -> Result<CgroupSysctlLink, ProgramError>

Takes ownership of the link referenced by the provided link_id.

The caller takes the responsibility of managing the lifetime of the link. When the returned CgroupSysctlLink is dropped, the link will be detached.

impl CgroupSysctl

pub fn unload(&mut self) -> Result<(), ProgramError>

Unloads the program from the kernel.

Tracked links will be detached before unloading the program. Attachment mechanisms that do not create tracked links are not affected. Note that owned links obtained using take_link() will not be detached.

impl CgroupSysctl

pub fn fd(&self) -> Result<&ProgramFd, ProgramError>

Returns the file descriptor of this Program.

impl CgroupSysctl

pub fn pin<P: AsRef<Path>>(&mut self, path: P) -> Result<(), PinError>

Pins the program to a BPF filesystem.

When a BPF object is pinned to a BPF filesystem it will remain loaded after Aya has unloaded the program. To remove the program, the file on the BPF filesystem must be removed. Any directories in the the path provided should have been created by the caller.

pub fn unpin(&mut self) -> Result<(), Error>

Removes the pinned link from the filesystem.

impl CgroupSysctl

pub fn from_pin<P: AsRef<Path>>(path: P) -> Result<Self, ProgramError>

Creates a program from a pinned entry on a bpffs.

Existing links will not be populated. To work with existing links you should use crate::programs::links::PinnedLink.

On drop, any managed links are detached and the program is unloaded. This will not result in the program being unloaded from the kernel if it is still pinned.

impl CgroupSysctl

pub fn from_program_info( info: ProgramInfo, name: Cow<'static, str>, ) -> Result<Self, ProgramError>

Constructs an instance of a Self from a ProgramInfo.

This allows the caller to get a handle to an already loaded program from the kernel without having to load it again.

Errors

• If the program type reported by the kernel does not match Self::PROGRAM_TYPE.
• If the file descriptor of the program cannot be cloned.

impl CgroupSysctl

pub fn info(&self) -> Result<ProgramInfo, ProgramError>

Returns metadata information of this program.

Uses kernel v4.13 features.

Trait Implementations

impl Debug for CgroupSysctl

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

Formats the value using the given formatter.

impl Drop for CgroupSysctl

fn drop(&mut self)

Executes the destructor for this type.

fn pin_drop(self: Pin<&mut Self>)

🔬This is a nightly-only experimental API. (pin_ergonomics)

Execute the destructor for this type, but different to Drop::drop, it requires self to be pinned.

impl<'a> TryFrom<&'a Program> for &'a CgroupSysctl

type Error = ProgramError

The type returned in the event of a conversion error.

fn try_from(program: &'a Program) -> Result<&'a CgroupSysctl, ProgramError>

Performs the conversion.

impl<'a> TryFrom<&'a mut Program> for &'a mut CgroupSysctl

type Error = ProgramError

The type returned in the event of a conversion error.

fn try_from( program: &'a mut Program, ) -> Result<&'a mut CgroupSysctl, ProgramError>

Performs the conversion.