The max allowed burst size for a single vhost enqueue is 32.
This code facilitates trying to send greater than the burst
size of packets to the vhost interface by adding a retry loop
and calling vhost enqueue multiple times. As this could
potentially block, a timeout is added.
Signed-off-by: Kevin Traynor <kevin.tray...@intel.com>
---
lib/netdev-dpdk.c | 43 +++++++++++++++++++++++++++++++++++++------
1 files changed, 37 insertions(+), 6 deletions(-)
diff --git a/lib/netdev-dpdk.c b/lib/netdev-dpdk.c
index cbb266d..3ab5995 100644
--- a/lib/netdev-dpdk.c
+++ b/lib/netdev-dpdk.c
@@ -104,6 +104,11 @@ BUILD_ASSERT_DECL((MAX_NB_MBUF /
ROUND_DOWN_POW2(MAX_NB_MBUF/MIN_NB_MBUF))
/* Character device cuse_dev_name. */
char *cuse_dev_name = NULL;
+/*
+ * Maximum amount of time in micro seconds to try and enqueue to vhost.
+ */
+#define VHOST_ENQ_RETRY_USECS 100
+
static const struct rte_eth_conf port_conf = {
.rxmode = {
.mq_mode = ETH_MQ_RX_RSS,
@@ -901,7 +906,12 @@ __netdev_dpdk_vhost_send(struct netdev *netdev, struct
dp_packet **pkts,
{
struct netdev_dpdk *vhost_dev = netdev_dpdk_cast(netdev);
struct virtio_net *virtio_dev = netdev_dpdk_get_virtio(vhost_dev);
- int tx_pkts, i;
+ struct rte_mbuf **cur_pkts = (struct rte_mbuf **) pkts;
+ unsigned int total_pkts = cnt;
+ unsigned int tx_pkts, i;
+ unsigned int expired = 0;
+ uint64_t start;
+ uint64_t timeout = VHOST_ENQ_RETRY_USECS * rte_get_timer_hz() / 1E6;
if (OVS_UNLIKELY(!is_vhost_running(virtio_dev))) {
ovs_mutex_lock(&vhost_dev->mutex);
@@ -912,16 +922,37 @@ __netdev_dpdk_vhost_send(struct netdev *netdev, struct
dp_packet **pkts,
/* There is vHost TX single queue, So we need to lock it for TX. */
rte_spinlock_lock(&vhost_dev->txq_lock);
- tx_pkts = rte_vhost_enqueue_burst(virtio_dev, VIRTIO_RXQ,
- (struct rte_mbuf **)pkts, cnt);
+ start = rte_get_timer_cycles();
+
+ do {
+ tx_pkts = rte_vhost_enqueue_burst(virtio_dev, VIRTIO_RXQ,
+ cur_pkts, cnt);
+ if (tx_pkts) {
+ /* Packets have been sent.*/
+ cnt -= tx_pkts;
+ /* Prepare for possible next iteration.*/
+ cur_pkts = &cur_pkts[tx_pkts];
+ } else {
+ /*
+ * Unable to enqueue packets to vhost interface.
+ * Check available entries before retrying.
+ */
+ while (!rte_vring_available_entries(virtio_dev, VIRTIO_RXQ)) {
+ if (OVS_UNLIKELY((rte_get_timer_cycles() - start) > timeout)) {
+ expired = 1;
+ break;
+ }
+ }
+ }
+ } while (cnt && !expired);
- vhost_dev->stats.tx_packets += tx_pkts;
- vhost_dev->stats.tx_dropped += (cnt - tx_pkts);
+ vhost_dev->stats.tx_packets += (total_pkts - cnt);
+ vhost_dev->stats.tx_dropped += cnt;
rte_spinlock_unlock(&vhost_dev->txq_lock);
out:
if (may_steal) {
- for (i = 0; i < cnt; i++) {
+ for (i = 0; i < total_pkts; i++) {
dp_packet_delete(pkts[i]);
}
}
--
1.7.4.1
_______________________________________________
dev mailing list
dev@openvswitch.org
http://openvswitch.org/mailman/listinfo/dev
