[RFC v2 PATCH 14/21] KVM: Directly handle interrupts by guests without VM EXIT on slave CPUs

Make interrupts on slave CPUs handled by guests without VM EXIT. This reduces CPU usage by the host to transfer interrupts of assigned PCI devices from the host to guests. It also reduces cost of VM EXIT and quickens response of guests to the interrupts. When a slave CPU is dedicated to a vCPU,

[RFC v2 PATCH 14/21] KVM: Directly handle interrupts by guests without VM EXIT on slave CPUs

Make interrupts on slave CPUs handled by guests without VM EXIT. This reduces CPU usage by the host to transfer interrupts of assigned PCI devices from the host to guests. It also reduces cost of VM EXIT and quickens response of guests to the interrupts. When a slave CPU is dedicated to a vCPU,