From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rusty Russell <rusty@rustcorp.com.au>
Subject: Re: virtio-net: why not always to set avail->flags to VRING_AVAIL_F_NO_INTERRUPT
Date: Thu, 04 Jun 2015 10:43:43 +0930
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References: <556E9F87.7030202@huawei.com>
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Cc: virtualization@lists.linux-foundation.org,
	"Michael S. Tsirkin" <mst@redhat.com>
To: Linhaifeng <haifeng.lin@huawei.com>, netdev@vger.kernel.org
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Linhaifeng <haifeng.lin@huawei.com> 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.