[dpdk-dev,v2] net/virtio: fix an incorrect behavior of device stop/start
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Commit Message
After starting a device, the driver shouldn't deliver the
packets that already existed before the device is started
to applications. Otherwise it will lead to incorrect packet
collection for port state. This patch fixes this issue by
flushing the Rx queues when starting the device.
Fixes: a85786dc816f ("virtio: fix states handling during initialization")
Cc: stable@dpdk.org
Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Reviewed-by: Jens Freimann <jfreimann@redhat.com>
---
v2:
- Use the existing `for` loop
- Improve the commit log
drivers/net/virtio/virtio_ethdev.c | 2 ++
drivers/net/virtio/virtio_rxtx.c | 2 +-
drivers/net/virtio/virtqueue.c | 25 +++++++++++++++++++++++++
drivers/net/virtio/virtqueue.h | 5 +++++
4 files changed, 33 insertions(+), 1 deletion(-)
Comments
On Fri, Oct 20, 2017 at 10:09:28AM +0800, Tiwei Bie wrote:
> After starting a device, the driver shouldn't deliver the
> packets that already existed before the device is started
> to applications. Otherwise it will lead to incorrect packet
> collection for port state. This patch fixes this issue by
> flushing the Rx queues when starting the device.
>
> Fixes: a85786dc816f ("virtio: fix states handling during initialization")
> Cc: stable@dpdk.org
>
> Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
> Reviewed-by: Jens Freimann <jfreimann@redhat.com>
Applied to dpdk-next-virtio.
Thanks.
--yliu
@@ -1819,6 +1819,8 @@ virtio_dev_start(struct rte_eth_dev *dev)
for (i = 0; i < dev->data->nb_rx_queues; i++) {
rxvq = dev->data->rx_queues[i];
+ /* Flush the old packets */
+ virtqueue_flush(rxvq->vq);
virtqueue_notify(rxvq->vq);
}
@@ -80,7 +80,7 @@ virtio_dev_rx_queue_done(void *rxq, uint16_t offset)
return VIRTQUEUE_NUSED(vq) >= offset;
}
-static void
+void
vq_ring_free_chain(struct virtqueue *vq, uint16_t desc_idx)
{
struct vring_desc *dp, *dp_tail;
@@ -59,3 +59,28 @@ virtqueue_detatch_unused(struct virtqueue *vq)
}
return NULL;
}
+
+/* Flush the elements in the used ring. */
+void
+virtqueue_flush(struct virtqueue *vq)
+{
+ struct vring_used_elem *uep;
+ struct vq_desc_extra *dxp;
+ uint16_t used_idx, desc_idx;
+ uint16_t nb_used, i;
+
+ nb_used = VIRTQUEUE_NUSED(vq);
+
+ for (i = 0; i < nb_used; i++) {
+ used_idx = vq->vq_used_cons_idx & (vq->vq_nentries - 1);
+ uep = &vq->vq_ring.used->ring[used_idx];
+ desc_idx = (uint16_t)uep->id;
+ dxp = &vq->vq_descx[desc_idx];
+ if (dxp->cookie != NULL) {
+ rte_pktmbuf_free(dxp->cookie);
+ dxp->cookie = NULL;
+ }
+ vq->vq_used_cons_idx++;
+ vq_ring_free_chain(vq, desc_idx);
+ }
+}
@@ -304,6 +304,9 @@ void virtqueue_dump(struct virtqueue *vq);
*/
struct rte_mbuf *virtqueue_detatch_unused(struct virtqueue *vq);
+/* Flush the elements in the used ring. */
+void virtqueue_flush(struct virtqueue *vq);
+
static inline int
virtqueue_full(const struct virtqueue *vq)
{
@@ -312,6 +315,8 @@ virtqueue_full(const struct virtqueue *vq)
#define VIRTQUEUE_NUSED(vq) ((uint16_t)((vq)->vq_ring.used->idx - (vq)->vq_used_cons_idx))
+void vq_ring_free_chain(struct virtqueue *vq, uint16_t desc_idx);
+
static inline void
vq_update_avail_idx(struct virtqueue *vq)
{