Re: [dpdk-stable] [PATCH] net/virtio: fix Rx stats with altivec vectorized functions

[Maxime Coquelin <maxime.coquelin@redhat.com>]

Thanks David for the fix,

On 9/30/19 8:27 PM, David Christensen wrote:
> With vectorized functions, only the rx stats for number of packets is
> incremented.
> Update also the other statistics.
> Performance impact is about 2%
> 
> Fixes: fc3d66212fed ("virtio: add vector Rx")
> Cc: stable@dpdk.org
> Cc: thibaut.collet@6wind.com
> Cc: maxime.coquelin@redhat.com
> Cc: tiwei.bie@intel.com
> Cc: zhihong.wang@intel.com

The commit message seems like a copy-paste, so claim about performance
impact may be not true, same for the Fixes line, which points to a
commit when altivec was not here yet.


I'll fix that when appyling:

Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>

Thanks,
Maxime

> Signed-off-by: David Christensen <drc@linux.vnet.ibm.com>
> ---
>  drivers/net/virtio/virtio_rxtx_simple_altivec.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/net/virtio/virtio_rxtx_simple_altivec.c b/drivers/net/virtio/virtio_rxtx_simple_altivec.c
> index 1cd732dec..f856396ab 100644
> --- a/drivers/net/virtio/virtio_rxtx_simple_altivec.c
> +++ b/drivers/net/virtio/virtio_rxtx_simple_altivec.c
> @@ -49,6 +49,7 @@ 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;
>  	const vector unsigned char zero = {0};
>  
> @@ -108,6 +109,7 @@ 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;) {
>  		vector unsigned char desc[RTE_VIRTIO_DESC_PER_LOOP / 2];
> @@ -199,5 +201,8 @@ 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++)
> +		virtio_update_packet_stats(&rxvq->stats, ref_rx_pkts[nb_used]);
> +
>  	return nb_pkts_received;
>  }
>