On 08/06/2012 01:17 PM, Avi Kivity wrote:

quoted

 
+4.77 KVM_EOIFD
+
+Capability: KVM_CAP_EOIFD
+Architectures: x86
+Type: vm ioctl
+Parameters: struct kvm_eoifd (in)
+Returns: 0 on success, < 0 on error
+
+KVM_EOIFD allows userspace to receive interrupt EOI notification
+through an eventfd.  kvm_eoifd.fd specifies the eventfd used for
+notification.  KVM_EOIFD_FLAG_DEASSIGN is used to de-assign an eoifd
+once assigned.  KVM_EOIFD also requires additional bits set in
+kvm_eoifd.flags to bind to the proper interrupt line.  The
+KVM_EOIFD_FLAG_LEVEL_IRQFD indicates that kvm_eoifd.key is provided
+and is a key from a level triggered interrupt (configured from
+KVM_IRQFD using KVM_IRQFD_FLAG_LEVEL).  The EOI notification is bound
+to the same GSI and irqchip input as the irqfd.  Both kvm_eoifd.key
+and KVM_EOIFD_FLAG_LEVEL_IRQFD must be specified on assignment and
+de-assignment of KVM_EOIFD.  A level irqfd may only be bound to a
+single eoifd.  KVM_CAP_EOIFD_LEVEL_IRQFD indicates support of
+KVM_EOIFD_FLAG_LEVEL_IRQFD.

Why do we need to couple eoifd and irqfd?

Oh, it's to auto-deassert the line.

Regarding the implementation, instead of a linked list, would an array
of counters parallel to the bitmap make it simpler?

-- 
error compiling committee.c: too many arguments to function