devices: virtio: convert Interrupt to use IrqLevelEvent

Instead of using a separate pair of events in Interrupt structure
convert it to use IrqLevelEvent.

BUG=None
TEST=./tools/presubmit

Change-Id: Ibf0fa69b96de4686fc58a1a431c3a983b7ed4de1
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosvm/+/3546575
Reviewed-by: Daniel Verkamp <dverkamp@chromium.org>
Tested-by: kokoro <noreply+kokoro@google.com>
Commit-Queue: Dmitry Torokhov <dtor@chromium.org>

crosvm-fuzz/block_fuzzer.rs

@@ -12,6 +12,7 @@ use std::sync::Arc;
 use base::Event;
 use cros_fuzz::fuzz_target;
 use devices::virtio::{base_features, Block, Interrupt, Queue, VirtioDevice};
+use devices::IrqLevelEvent;
 use hypervisor::ProtectionType;
 use vm_memory::{GuestAddress, GuestMemory};
 
@@ -87,8 +88,7 @@ fuzz_target!(|bytes| {
         mem,
         Interrupt::new(
             Arc::new(AtomicUsize::new(0)),
-            Event::new().unwrap(),
-            Event::new().unwrap(),
+            IrqLevelEvent::new().unwrap(),
             None,   // msix_config
             0xFFFF, // VIRTIO_MSI_NO_VECTOR
         ),

devices/src/virtio/interrupt.rs

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 use super::{INTERRUPT_STATUS_CONFIG_CHANGED, INTERRUPT_STATUS_USED_RING, VIRTIO_MSI_NO_VECTOR};
+use crate::irq_event::IrqLevelEvent;
 use crate::pci::MsixConfig;
 use base::Event;
 use std::sync::atomic::{AtomicUsize, Ordering};
@@ -31,8 +32,7 @@ pub trait SignalableInterrupt {
 
 pub struct Interrupt {
     interrupt_status: Arc<AtomicUsize>,
-    interrupt_evt: Event,
-    interrupt_resample_evt: Event,
+    interrupt_evt: IrqLevelEvent,
     msix_config: Option<Arc<Mutex<MsixConfig>>>,
     config_msix_vector: u16,
 }
@@ -62,7 +62,7 @@ impl SignalableInterrupt for Interrupt {
             == 0
         {
             // Write to irqfd to inject INTx interrupt
-            self.interrupt_evt.write(1).unwrap();
+            self.interrupt_evt.trigger().unwrap();
         }
     }
 
@@ -71,12 +71,12 @@ impl SignalableInterrupt for Interrupt {
     }
 
     fn get_resample_evt(&self) -> Option<&Event> {
-        Some(&self.interrupt_resample_evt)
+        Some(self.interrupt_evt.get_resample())
     }
 
     fn do_interrupt_resample(&self) {
         if self.interrupt_status.load(Ordering::SeqCst) != 0 {
-            self.interrupt_evt.write(1).unwrap();
+            self.interrupt_evt.trigger().unwrap();
         }
     }
 }
@@ -105,15 +105,13 @@ impl<I: SignalableInterrupt> SignalableInterrupt for Arc<Mutex<I>> {
 impl Interrupt {
     pub fn new(
         interrupt_status: Arc<AtomicUsize>,
-        interrupt_evt: Event,
-        interrupt_resample_evt: Event,
+        interrupt_evt: IrqLevelEvent,
         msix_config: Option<Arc<Mutex<MsixConfig>>>,
         config_msix_vector: u16,
     ) -> Interrupt {
         Interrupt {
             interrupt_status,
             interrupt_evt,
-            interrupt_resample_evt,
             msix_config,
             config_msix_vector,
         }
@@ -121,12 +119,12 @@ impl Interrupt {
 
     /// Get a reference to the interrupt event.
     pub fn get_interrupt_evt(&self) -> &Event {
-        &self.interrupt_evt
+        self.interrupt_evt.get_trigger()
     }
 
     /// Handle interrupt resampling event, reading the value from the event and doing the resample.
     pub fn interrupt_resample(&self) {
-        let _ = self.interrupt_resample_evt.read();
+        self.interrupt_evt.clear_resample();
         self.do_interrupt_resample();
     }
 

devices/src/virtio/queue.rs

@@ -621,7 +621,7 @@ impl Queue {
 mod tests {
     use super::super::Interrupt;
     use super::*;
-    use base::Event;
+    use crate::IrqLevelEvent;
     use std::convert::TryInto;
     use std::sync::atomic::AtomicUsize;
     use std::sync::Arc;
@@ -723,8 +723,7 @@ mod tests {
 
         let interrupt = Interrupt::new(
             Arc::new(AtomicUsize::new(0)),
-            Event::new().unwrap(),
-            Event::new().unwrap(),
+            IrqLevelEvent::new().unwrap(),
             None,
             10,
         );
@@ -800,8 +799,7 @@ mod tests {
 
         let interrupt = Interrupt::new(
             Arc::new(AtomicUsize::new(0)),
-            Event::new().unwrap(),
-            Event::new().unwrap(),
+            IrqLevelEvent::new().unwrap(),
             None,
             10,
         );

devices/src/virtio/vhost/net.rs

@@ -355,6 +355,7 @@ pub mod tests {
     use super::*;
     use crate::virtio::base_features;
     use crate::virtio::VIRTIO_MSI_NO_VECTOR;
+    use crate::IrqLevelEvent;
     use hypervisor::ProtectionType;
     use net_util::fakes::FakeTap;
     use std::path::PathBuf;
@@ -417,8 +418,7 @@ pub mod tests {
             guest_memory,
             Interrupt::new(
                 Arc::new(AtomicUsize::new(0)),
-                Event::new().unwrap(),
-                Event::new().unwrap(),
+                IrqLevelEvent::new().unwrap(),
                 None,
                 VIRTIO_MSI_NO_VECTOR,
             ),

devices/src/virtio/virtio_pci_device.rs

@@ -23,6 +23,7 @@ use crate::pci::{
     PciDeviceError, PciDisplaySubclass, PciHeaderType, PciId, PciInterruptPin, PciSubclass,
 };
 use crate::virtio::ipc_memory_mapper::IpcMemoryMapper;
+use crate::IrqLevelEvent;
 
 use self::virtio_pci_common_config::VirtioPciCommonConfig;
 
@@ -451,8 +452,7 @@ impl VirtioPciDevice {
 
         let interrupt = Interrupt::new(
             self.interrupt_status.clone(),
-            interrupt_evt,
-            interrupt_resample_evt,
+            IrqLevelEvent::from_event_pair(interrupt_evt, interrupt_resample_evt),
             Some(self.msix_config.clone()),
             self.common_config.msix_config,
         );