[dpdk-dev,20/22] example/vhost: Avoid inserting vlan twice
Commit Message
Check if it has already been vlan-tagged packet, if true, avoid inserting a
duplicated vlan tag into it.
This is a possible case when guest has the capability of inserting vlan tag.
Signed-off-by: Changchun Ouyang <changchun.ouyang@intel.com>
---
examples/vhost/main.c | 18 ++++++++++++++----
1 file changed, 14 insertions(+), 4 deletions(-)
@@ -1120,6 +1120,7 @@ virtio_tx_route(struct vhost_dev *vdev, struct rte_mbuf *m, uint16_t vlan_tag)
unsigned len, ret, offset = 0;
const uint16_t lcore_id = rte_lcore_id();
struct virtio_net *dev = vdev->dev;
+ struct ether_hdr *nh;
/*check if destination is local VM*/
if ((vm2vm_mode == VM2VM_SOFTWARE) && (virtio_tx_local(vdev, m) == 0)) {
@@ -1141,12 +1142,21 @@ virtio_tx_route(struct vhost_dev *vdev, struct rte_mbuf *m, uint16_t vlan_tag)
tx_q = &lcore_tx_queue[lcore_id];
len = tx_q->len;
- m->ol_flags = PKT_TX_VLAN_PKT;
+ nh = rte_pktmbuf_mtod(m, struct ether_hdr *);
+ if (unlikely(nh->ether_type == rte_cpu_to_be_16(ETHER_TYPE_VLAN))) {
+ /* Guest has inserted the vlan tag. */
+ struct vlan_hdr *vh = (struct vlan_hdr *) (nh + 1);
+ uint16_t vlan_tag_be = rte_cpu_to_be_16(vlan_tag);
+ if (vh->vlan_tci != vlan_tag_be)
+ vh->vlan_tci = vlan_tag_be;
+ } else {
+ m->ol_flags = PKT_TX_VLAN_PKT;
- m->data_len += offset;
- m->pkt_len += offset;
+ m->data_len += offset;
+ m->pkt_len += offset;
- m->vlan_tci = vlan_tag;
+ m->vlan_tci = vlan_tag;
+ }
tx_q->m_table[len] = m;
len++;