Struct aya::maps::PerCpuArray

pub struct PerCpuArray<T: Deref<Target = Map>, V: Pod> { /* fields omitted */ }

A per-CPU fixed-size array.

The size of the array is defined on the eBPF side using the bpf_map_def::max_entries field. All the entries are zero-initialized when the map is created.

Examples

use aya::maps::{PerCpuArray, PerCpuValues};
use aya::util::nr_cpus;
use std::convert::TryFrom;

let mut array = PerCpuArray::try_from(bpf.map_mut("ARRAY")?)?;

// set array[1] = 42 for all cpus
let nr_cpus = nr_cpus()?;
array.set(1, PerCpuValues::try_from(vec![42u32; nr_cpus])?, 0)?;

// retrieve the values at index 1 for all cpus
let values = array.get(&1, 0)?;
assert_eq!(values.len(), nr_cpus);
for cpu_val in values.iter() {
    assert_eq!(*cpu_val, 42u32);
}

Implementations

impl<T: Deref<Target = Map>, V: Pod> PerCpuArray<T, V>

pub fn len(&self) -> u32

Returns the number of elements in the array.

This corresponds to the value of bpf_map_def::max_entries on the eBPF side.

pub fn get(&self, index: &u32, flags: u64) -> Result<PerCpuValues<V>, MapError>

Returns a slice of values - one for each CPU - stored at the given index.

Errors

Returns MapError::OutOfBounds if index is out of bounds, MapError::SyscallError if bpf_map_lookup_elem fails.

pub unsafe fn iter<'a>(
    &'a self
) -> impl Iterator<Item = Result<PerCpuValues<V>, MapError>> + 'a

An iterator over the elements of the array. The iterator item type is Result<PerCpuValues<V>, MapError>.

impl<T: Deref<Target = Map> + DerefMut<Target = Map>, V: Pod> PerCpuArray<T, V>

pub fn set(
    &mut self,
    index: u32,
    values: PerCpuValues<V>,
    flags: u64
) -> Result<(), MapError>

Sets the values - one for each CPU - at the given index.

Errors

Returns MapError::OutOfBounds if index is out of bounds, MapError::SyscallError if bpf_map_update_elem fails.

Trait Implementations

impl<V: Pod> TryFrom<MapRef> for PerCpuArray<MapRef, V>

type Error = MapError

The type returned in the event of a conversion error.

fn try_from(a: MapRef) -> Result<PerCpuArray<MapRef, V>, MapError>

Performs the conversion.

impl<V: Pod> TryFrom<MapRefMut> for PerCpuArray<MapRefMut, V>

type Error = MapError

The type returned in the event of a conversion error.

fn try_from(a: MapRefMut) -> Result<PerCpuArray<MapRefMut, V>, MapError>

Performs the conversion.