Re: [PATCH 1/4] KVM: Using kfifo for irq recording

[Avi Kivity <avi@redhat.com>]

Sheng Yang wrote:
> For MSI-X, we have to deal with multiply IRQ with same IRQ handler, so it's
> necessary to record the IRQ that trigger the IRQ handler.
>
>   

Does MSI-X disallowing coalescing two requests into one interrupt?  Or 
can we still coalesce interrupts (perhaps by recording them as a (irq, 
cpu) pair?)

> @@ -313,6 +314,9 @@ struct kvm_assigned_dev_kernel {
>  	int host_irq;
>  	bool host_irq_disabled;
>  	int guest_irq;
> +#define KVM_ASSIGNED_DEV_IRQ_FIFO_LEN	0x100
> +	struct kfifo *irq_fifo;
> +	spinlock_t irq_fifo_lock;
>  #define KVM_ASSIGNED_DEV_GUEST_INTX	(1 << 0)
>   

What if it runs out?

What does real hardware do?  I'm sure it doesn't have a 100-entry queue.

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