From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Wang, Zhihong" <zhihong.wang@intel.com>
Subject: Re: [PATCH v5 2/6] vhost: rewrite enqueue
Date: Wed, 14 Sep 2016 08:20:20 +0000
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Cc: "yuanhan.liu@linux.intel.com" <yuanhan.liu@linux.intel.com>,
 "thomas.monjalon@6wind.com" <thomas.monjalon@6wind.com>
To: Maxime Coquelin <maxime.coquelin@redhat.com>, "dev@dpdk.org" <dev@dpdk.org>
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> > +				desc_current =3D
> > +					vq->avail->ring[(vq->last_used_idx)
> &
> > +					(vq->size - 1)];
> > +				desc_chain_head =3D desc_current;
> > +				desc =3D &vq->desc[desc_current];
> > +				desc_addr =3D gpa_to_vva(dev, desc->addr);
> > +				if (unlikely(!desc_addr))
> > +					goto error;
> >
> > -			desc =3D &vq->desc[desc->next];
> > -			desc_addr =3D gpa_to_vva(dev, desc->addr);
> > -			if (unlikely(!desc_addr))
> > -				return -1;
> > -
> > -			desc_offset =3D 0;
> > -			desc_avail  =3D desc->len;
> > +				desc_chain_len =3D 0;
> > +				desc_offset =3D 0;
> As I commented on v3, there is code duplication between next flag, and
> mrg buf cases:
> desc_offset =3D 0;
>=20
> and:
>=20
> desc =3D &vq->desc[desc_current];
> desc_addr =3D gpa_to_vva(dev, desc->addr);
> if (unlikely(!desc_addr))
>      goto error;
>=20

Do you mean to add something like:

static inline int __attribute__((always_inline))
get_desc(struct virtio_net *dev, struct vhost_virtqueue *vq,
                uint32_t desc_idx, struct vring_desc **desc,
                uint64_t *desc_addr)
{
        *desc =3D &vq->desc[desc_idx];
        *desc_addr =3D gpa_to_vva(dev, (*desc)->addr);
        if (unlikely(!(*desc_addr)))
                return -1;

        return 0;
}


> Regards,
> Maxime