Re: [dpdk-dev] [dpdk-stable] [PATCH 19.11 V2 08/12] virtio: fix rx stats with vectorized functions

[Tiwei Bie <tiwei.bie@intel.com>]

On Wed, Aug 07, 2019 at 05:09:17PM +0200, Thierry Herbelot wrote:
> From: Thibaut Collet <thibaut.collet@6wind.com>
> 
> With vectorized functions, only the rx stats for number of packets is
> incremented.
> Update also the other statistics.
> Performance impact is about 2%

Could you share some details about your performance test?


> diff --git a/drivers/net/virtio/virtio_rxtx_simple_sse.c b/drivers/net/virtio/virtio_rxtx_simple_sse.c
> index af76708d66ae..c757e8c9d601 100644
> --- a/drivers/net/virtio/virtio_rxtx_simple_sse.c
> +++ b/drivers/net/virtio/virtio_rxtx_simple_sse.c
> @@ -48,6 +48,7 @@ virtio_recv_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
>  	struct vring_used_elem *rused;
>  	struct rte_mbuf **sw_ring;
>  	struct rte_mbuf **sw_ring_end;
> +	struct rte_mbuf **ref_rx_pkts;
>  	uint16_t nb_pkts_received = 0;
>  	__m128i shuf_msk1, shuf_msk2, len_adjust;
>  
> @@ -107,6 +108,7 @@ virtio_recv_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
>  			virtqueue_notify(vq);
>  	}
>  
> +	ref_rx_pkts = rx_pkts;
>  	for (nb_pkts_received = 0;
>  		nb_pkts_received < nb_used;) {
>  		__m128i desc[RTE_VIRTIO_DESC_PER_LOOP / 2];
> @@ -190,5 +192,9 @@ virtio_recv_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
>  	vq->vq_used_cons_idx += nb_pkts_received;
>  	vq->vq_free_cnt += nb_pkts_received;
>  	rxvq->stats.packets += nb_pkts_received;
> +	for (nb_used = 0; nb_used < nb_pkts_received; nb_used++) {
> +		rxvq->stats.bytes += ref_rx_pkts[nb_used]->pkt_len;
> +		virtio_update_packet_stats(&rxvq->stats, ref_rx_pkts[nb_used]);

The stats.bytes was updated twice by above code.

> +	}
>  	return nb_pkts_received;
>  }
> -- 
> 2.11.0
>