On Tue, Oct 27, 2015 at 03:12:53PM +0900, Tetsuya Mukawa wrote:
> The patch fixes wrong handling of virtqueue array index.
>
> GET_VRING_BASE:
> The vhost backend will receive the message per virtqueue.
> Also we should call a destroy callback when both RXQ and TXQ receives
> the message.
>
> SET_BACKEND:
> Because vhost library supports multiple queue, the index may be over 2.
> Also a vhost frontend(QEMU) may send such a index.
Note that only vhost-user supports MQ. vhost-cuse does not.
> Signed-off-by: Tetsuya Mukawa <mukawa at igel.co.jp>
> ---
> lib/librte_vhost/vhost_user/virtio-net-user.c | 22 +++++++++++-----------
> lib/librte_vhost/virtio-net.c | 5 +++--
> 2 files changed, 14 insertions(+), 13 deletions(-)
>
> diff --git a/lib/librte_vhost/vhost_user/virtio-net-user.c
> b/lib/librte_vhost/vhost_user/virtio-net-user.c
> index a998ad8..3e8dfea 100644
> --- a/lib/librte_vhost/vhost_user/virtio-net-user.c
> +++ b/lib/librte_vhost/vhost_user/virtio-net-user.c
> @@ -283,12 +283,10 @@ user_get_vring_base(struct vhost_device_ctx ctx,
> struct vhost_vring_state *state)
> {
> struct virtio_net *dev = get_device(ctx);
> + uint16_t base_idx = state->index / VIRTIO_QNUM;
So, fixing what my 1st reply said, for Nth queue pair, state->index
is "N * 2 + is_tx". So, the base should be "state->index / 2 * 2".
>
> if (dev == NULL)
> return -1;
> - /* We have to stop the queue (virtio) if it is running. */
> - if (dev->flags & VIRTIO_DEV_RUNNING)
> - notify_ops->destroy_device(dev);
>
> /* Here we are safe to get the last used index */
> ops->get_vring_base(ctx, state->index, state);
> @@ -300,15 +298,17 @@ user_get_vring_base(struct vhost_device_ctx ctx,
> * sent and only sent in vhost_vring_stop.
> * TODO: cleanup the vring, it isn't usable since here.
> */
> - if (dev->virtqueue[state->index + VIRTIO_RXQ]->kickfd >= 0) {
> - close(dev->virtqueue[state->index + VIRTIO_RXQ]->kickfd);
> - dev->virtqueue[state->index + VIRTIO_RXQ]->kickfd = -1;
> - }
> - if (dev->virtqueue[state->index + VIRTIO_TXQ]->kickfd >= 0) {
> - close(dev->virtqueue[state->index + VIRTIO_TXQ]->kickfd);
> - dev->virtqueue[state->index + VIRTIO_TXQ]->kickfd = -1;
> + if (dev->virtqueue[state->index]->kickfd >= 0) {
> + close(dev->virtqueue[state->index]->kickfd);
> + dev->virtqueue[state->index]->kickfd = -1;
> }
>
> + /* We have to stop the queue (virtio) if it is running. */
> + if ((dev->flags & VIRTIO_DEV_RUNNING) &&
> + (dev->virtqueue[base_idx + VIRTIO_RXQ]->kickfd == -1) &&
> + (dev->virtqueue[base_idx + VIRTIO_TXQ]->kickfd == -1))
> + notify_ops->destroy_device(dev);
This is a proper fix then. (You just need fix base_idx).
> return 0;
> }
>
> @@ -321,7 +321,7 @@ user_set_vring_enable(struct vhost_device_ctx ctx,
> struct vhost_vring_state *state)
> {
> struct virtio_net *dev = get_device(ctx);
> - uint16_t base_idx = state->index;
> + uint16_t base_idx = state->index / VIRTIO_QNUM;
user_set_vring_enable is sent per queue pair (I'm sure this time), so
base_idx equals to state->index. No need fix here.
> int enable = (int)state->num;
>
> RTE_LOG(INFO, VHOST_CONFIG,
> diff --git a/lib/librte_vhost/virtio-net.c b/lib/librte_vhost/virtio-net.c
> index 97213c5..ee2e84d 100644
> --- a/lib/librte_vhost/virtio-net.c
> +++ b/lib/librte_vhost/virtio-net.c
> @@ -778,6 +778,7 @@ static int
> set_backend(struct vhost_device_ctx ctx, struct vhost_vring_file *file)
> {
> struct virtio_net *dev;
> + uint32_t base_idx = file->index / VIRTIO_QNUM;
As stated, vhost-cuse doesn't not support MQ.
--yliu
>
> dev = get_device(ctx);
> if (dev == NULL)
> @@ -791,8 +792,8 @@ set_backend(struct vhost_device_ctx ctx, struct
> vhost_vring_file *file)
> * we add the device.
> */
> if (!(dev->flags & VIRTIO_DEV_RUNNING)) {
> - if (((int)dev->virtqueue[VIRTIO_TXQ]->backend !=
> VIRTIO_DEV_STOPPED) &&
> - ((int)dev->virtqueue[VIRTIO_RXQ]->backend !=
> VIRTIO_DEV_STOPPED)) {
> + if (((int)dev->virtqueue[base_idx + VIRTIO_RXQ]->backend !=
> VIRTIO_DEV_STOPPED) &&
> + ((int)dev->virtqueue[base_idx + VIRTIO_TXQ]->backend !=
> VIRTIO_DEV_STOPPED)) {
> return notify_ops->new_device(dev);
> }
> /* Otherwise we remove it. */
> --
> 2.1.4
