Subject: Re: virtio-net: why not always to set avail->flags to VRING_AVAIL_F_NO_INTERRUPT

From: Rusty Russell <[email-masked]>
Date: Thu, 04 Jun 2015 10:43:43 +0930

Linhaifeng <[email-masked]> writes:
> Hi,
>
> I'm a newbie and have a question about vring_new_virtqueue function.
>
> Why we set avail->flags to VRING_AVAIL_F_NO_INTERRUPT when no callbacks?
> I think we should set avail->flags to VRING_AVAIL_F_NO_INTERRUPT even if no callbacks.

Hi Linhaifeng,

        Not sure I understand your question, but I'll try to answer.

We don't set VRING_AVAIL_F_NO_INTERRUPT if there's a callback because we
want that callback called.  Otherwise callback will never be used.

Cheers,
Rusty.