In merge-able RX path, vhost injects interrupts to guest for each packet. This should degrade performance a lot. This patch fixes this issue by injecting one interrupt for a batch of packets.
Signed-off-by: Huawei Xie <huawei.xie at intel.com> --- lib/librte_vhost/vhost_rxtx.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/lib/librte_vhost/vhost_rxtx.c b/lib/librte_vhost/vhost_rxtx.c index 0d07338..9d3165a 100644 --- a/lib/librte_vhost/vhost_rxtx.c +++ b/lib/librte_vhost/vhost_rxtx.c @@ -496,7 +496,7 @@ virtio_dev_merge_rx(struct virtio_net *dev, uint16_t queue_id, "to get enough desc from " "vring\n", dev->device_fh); - return pkt_idx; + goto merge_rx_exit; } else { update_secure_len(vq, res_cur_idx, &secure_len, &vec_idx); res_cur_idx++; @@ -523,7 +523,10 @@ virtio_dev_merge_rx(struct virtio_net *dev, uint16_t queue_id, *(volatile uint16_t *)&vq->used->idx += entry_success; vq->last_used_idx = res_cur_idx; + } +merge_rx_exit: + if (likely(pkt_idx)) { /* flush used->idx update before we read avail->flags. */ rte_mb(); @@ -532,7 +535,7 @@ virtio_dev_merge_rx(struct virtio_net *dev, uint16_t queue_id, eventfd_write((int)vq->callfd, 1); } - return count; + return pkt_idx; } uint16_t -- 1.9.3