From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH RFC 2/2] vhost: support urgent descriptors
Date: Sat, 20 Sep 2014 12:00:27 +0200
Message-ID: <541D503B.3070507@redhat.com>
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To: Jason Wang <jasowang@redhat.com>, "Michael S. Tsirkin" <mst@redhat.com>, linux-kernel@vger.kernel.org
Cc: kvm@vger.kernel.org, virtualization@lists.linux-foundation.org
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Il 19/09/2014 09:10, Jason Wang ha scritto:
>> >  
>> > -	if (!vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX)) {
>> > +	if (vq->urgent || !vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX)) {
> So the urgent descriptor only work when event index was not enabled?
> This seems suboptimal, we may still want to benefit from event index
> even if urgent descriptor is used. Looks like we need return true here
> when vq->urgent is true?

Its ||, not &&.

Without event index, all descriptors are treated as urgent.

Paolo