From 9e915a0284fa6e1ae9d719fe44fdaf159a70de87 Mon Sep 17 00:00:00 2001
From: Sebastien Boeuf <sebastien.boeuf@intel.com>
Date: Wed, 4 Mar 2020 16:19:37 +0100
Subject: [PATCH] vmm: Remove all Weak references from CpuManager

Now that the BusDevice devices are stored as Weak references by the
IO and MMIO buses, there's no need to use Weak references from the
CpuManager anymore.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
---
 vmm/src/cpu.rs | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/vmm/src/cpu.rs b/vmm/src/cpu.rs
index ee47a1f43..ba0c46258 100644
--- a/vmm/src/cpu.rs
+++ b/vmm/src/cpu.rs
@@ -20,7 +20,7 @@ use libc::{c_void, siginfo_t};
 use std::cmp;
 use std::os::unix::thread::JoinHandleExt;
 use std::sync::atomic::{AtomicBool, Ordering};
-use std::sync::{Arc, Barrier, Mutex, Weak};
+use std::sync::{Arc, Barrier, Mutex};
 use std::thread;
 use std::{fmt, io, result};
 use vm_device::{Migratable, MigratableError, Pausable, Snapshotable};
@@ -372,7 +372,7 @@ impl Vcpu {
 pub struct CpuManager {
     boot_vcpus: u8,
     max_vcpus: u8,
-    io_bus: Weak<devices::Bus>,
+    io_bus: Arc<devices::Bus>,
     mmio_bus: Arc<devices::Bus>,
     ioapic: Option<Arc<Mutex<ioapic::Ioapic>>>,
     vm_memory: GuestMemoryAtomic<GuestMemoryMmap>,
@@ -507,7 +507,7 @@ impl CpuManager {
         let cpu_manager = Arc::new(Mutex::new(CpuManager {
             boot_vcpus,
             max_vcpus,
-            io_bus: Arc::downgrade(&device_manager.io_bus()),
+            io_bus: device_manager.io_bus(),
             mmio_bus: device_manager.mmio_bus().clone(),
             ioapic: device_manager.ioapic().clone(),
             vm_memory: guest_memory,
@@ -531,8 +531,6 @@ impl CpuManager {
             .lock()
             .unwrap()
             .io_bus
-            .upgrade()
-            .unwrap()
             .insert(cpu_manager.clone(), 0x0cd8, 0xc)
             .map_err(Error::BusError)?;
 
@@ -563,7 +561,7 @@ impl CpuManager {
             let mut vcpu = Vcpu::new(
                 cpu_id,
                 &self.fd,
-                self.io_bus.clone().upgrade().unwrap(),
+                self.io_bus.clone(),
                 self.mmio_bus.clone(),
                 ioapic,
                 creation_ts,