Struct IrqLevelEvent

pub struct IrqLevelEvent {
    trigger_evt: Event,
    resample_evt: Event,
}

A structure suitable for implementing level triggered interrupts in device backends.

Level-triggered interrupts require the device to monitor a resample event from the IRQ chip, which can be retrieved with IrqLevelEvent::get_resample(). When the guest OS acknowledges the interrupt with an End of Interrupt (EOI) command, the IRQ chip will signal the resample event. Each time the resample event is signalled, the device should re-check its state and call IrqLevelEvent::trigger() again if the interrupt should still be asserted.

Fields

trigger_evt: Event

An event used by the device backend to signal hypervisor/VM about data or new unit of work being available.

resample_evt: Event

An event used by the hypervisor to signal device backend that it completed processing a unit of work and that device should re-raise trigger_evt if additional work needs to be done.

Implementations

impl IrqLevelEvent

pub fn new() -> Result<IrqLevelEvent>

pub fn try_clone(&self) -> Result<IrqLevelEvent>

pub fn from_event_pair(trigger_evt: Event, resample_evt: Event) -> IrqLevelEvent

Creates an instance of IrqLevelEvent from an existing pair of events.

pub fn get_trigger(&self) -> &Event

pub fn get_resample(&self) -> &Event

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

Allows backend to inject interrupt (typically into guest).

pub fn clear_trigger(&self)

Allows code servicing interrupt to consume or clear the event.

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

Allows code servicing interrupt to signal that processing is done and that the backend should go ahead and re-trigger it if there is more work needs to be done. Note that typically resampling is signalled not by individual backends, but rather by the code implementing interrupt controller.

pub fn clear_resample(&self)

Allows backend to consume or clear the resample event.

Trait Implementations

impl AsRawDescriptors for IrqLevelEvent

fn as_raw_descriptors(&self) -> Vec<RawDescriptor>

Returns the underlying raw descriptors.

impl Debug for IrqLevelEvent

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for IrqLevelEvent

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for IrqLevelEvent

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.