From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jens Freimann <jfreimann@redhat.com>
Subject: Re: [RFC 01/19] vhost: protect virtio_net device struct
Date: Wed, 5 Jul 2017 12:07:58 +0200
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References: <20170704094922.11405-1-maxime.coquelin@redhat.com>
 <20170704094922.11405-2-maxime.coquelin@redhat.com>
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Cc: dev@dpdk.org, Yuanhan Liu <yliu@fridaylinux.org>, mst@redhat.com,
 vkaplans@redhat.com, jasowang@redhat.com
To: Maxime Coquelin <maxime.coquelin@redhat.com>
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On Tue, Jul 04, 2017 at 11:49:04AM +0200, Maxime Coquelin wrote:
>virtio_net device might be accessed while being reallocated
>in case of NUMA awareness. This case might be theoretical,
>but it will be needed anyway to protect vrings pages against
>invalidation.
>
>The virtio_net devs are now protected with a readers/writers
>lock, so that before reallocating the device, it is ensured
>that it is not being referenced by the processing threads.
>
>Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
>---
> lib/librte_vhost/vhost.c      | 223 +++++++++++++++++++++++++++++++++++-------
> lib/librte_vhost/vhost.h      |   3 +-
> lib/librte_vhost/vhost_user.c |  73 +++++---------
> lib/librte_vhost/virtio_net.c |  17 +++-
> 4 files changed, 228 insertions(+), 88 deletions(-)
[...]
>+int
>+realloc_device(int vid, int vq_index, int node)
>+{
>+	struct virtio_net *dev, *old_dev;
>+	struct vhost_virtqueue *vq;
>+
>+	dev = rte_malloc_socket(NULL, sizeof(*dev), 0, node);
>+	if (!dev)
>+		return -1;
>+
>+	vq = rte_malloc_socket(NULL, sizeof(*vq), 0, node);
>+	if (!vq)
>+		return -1;
>+
>+	old_dev = get_device_wr(vid);
>+	if (!old_dev)
>+		return -1;

Should we free vq and dev here?

regards,
Jens