Re: [dpdk-stable] [PATCH] net/virtio: fix vectorized Rx queue stuck

["Xueming(Steven) Li" <xuemingl@nvidia.com>]

+@谢华伟(此时此刻） <huawei.xhw@alibaba-inc.com>

> -----Original Message-----
> From: Xueming Li <xuemingl@nvidia.com>
> Sent: Wednesday, April 14, 2021 12:27 PM
> Cc: dev@dpdk.org; Xueming(Steven) Li <xuemingl@nvidia.com>; huawei.xie@intel.com; jerin.jacob@caviumnetworks.com;
> drc@linux.vnet.ibm.com; stable@dpdk.org; Maxime Coquelin <maxime.coquelin@redhat.com>; Chenbo Xia <chenbo.xia@intel.com>;
> Jerin Jacob <jerinj@marvell.com>; Ruifeng Wang <ruifeng.wang@arm.com>; Bruce Richardson <bruce.richardson@intel.com>;
> Konstantin Ananyev <konstantin.ananyev@intel.com>; Jianfeng Tan <jianfeng.tan@intel.com>; Jianbo Liu <jianbo.liu@linaro.org>;
> Yuanhan Liu <yuanhan.liu@linux.intel.com>
> Subject: [PATCH] net/virtio: fix vectorized Rx queue stuck
> 
> When Rx burst size >= Rx queue size, all descriptors in used queue consumed without rearm, the next Rx burst found no new packets
> and returned directly without rearm as well.
> 
> This patch rearms available queue at once after rx_burst to avoid vq hungry.
> 
> Fixes: fc3d66212fed ("virtio: add vector Rx")
> Cc: huawei.xie@intel.com
> Fixes: 2d7c37194ee4 ("net/virtio: add NEON based Rx handler")
> Cc: jerin.jacob@caviumnetworks.com
> Fixes: 52b5a707e6ca ("net/virtio: add Altivec Rx")
> Cc: drc@linux.vnet.ibm.com
> Cc: stable@dpdk.org
> 
> Signed-off-by: Xueming Li <xuemingl@nvidia.com>
> ---
>  drivers/net/virtio/virtio_rxtx_simple_altivec.c | 12 ++++++------
>  drivers/net/virtio/virtio_rxtx_simple_neon.c    | 12 ++++++------
>  drivers/net/virtio/virtio_rxtx_simple_sse.c     | 12 ++++++------
>  3 files changed, 18 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/net/virtio/virtio_rxtx_simple_altivec.c b/drivers/net/virtio/virtio_rxtx_simple_altivec.c
> index 62e5100a48..1ffae234da 100644
> --- a/drivers/net/virtio/virtio_rxtx_simple_altivec.c
> +++ b/drivers/net/virtio/virtio_rxtx_simple_altivec.c
> @@ -102,12 +102,6 @@ virtio_recv_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
> 
>  	rte_prefetch0(rused);
> 
> -	if (vq->vq_free_cnt >= RTE_VIRTIO_VPMD_RX_REARM_THRESH) {
> -		virtio_rxq_rearm_vec(rxvq);
> -		if (unlikely(virtqueue_kick_prepare(vq)))
> -			virtqueue_notify(vq);
> -	}
> -
>  	nb_total = nb_used;
>  	ref_rx_pkts = rx_pkts;
>  	for (nb_pkts_received = 0;
> @@ -204,5 +198,11 @@ virtio_recv_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
>  	for (nb_used = 0; nb_used < nb_pkts_received; nb_used++)
>  		virtio_update_packet_stats(&rxvq->stats, ref_rx_pkts[nb_used]);
> 
> +	if (vq->vq_free_cnt >= RTE_VIRTIO_VPMD_RX_REARM_THRESH) {
> +		virtio_rxq_rearm_vec(rxvq);
> +		if (unlikely(virtqueue_kick_prepare(vq)))
> +			virtqueue_notify(vq);
> +	}
> +
>  	return nb_pkts_received;
>  }
> diff --git a/drivers/net/virtio/virtio_rxtx_simple_neon.c b/drivers/net/virtio/virtio_rxtx_simple_neon.c
> index c8e4b13a02..341dedce41 100644
> --- a/drivers/net/virtio/virtio_rxtx_simple_neon.c
> +++ b/drivers/net/virtio/virtio_rxtx_simple_neon.c
> @@ -100,12 +100,6 @@ virtio_recv_pkts_vec(void *rx_queue,
> 
>  	rte_prefetch_non_temporal(rused);
> 
> -	if (vq->vq_free_cnt >= RTE_VIRTIO_VPMD_RX_REARM_THRESH) {
> -		virtio_rxq_rearm_vec(rxvq);
> -		if (unlikely(virtqueue_kick_prepare(vq)))
> -			virtqueue_notify(vq);
> -	}
> -
>  	nb_total = nb_used;
>  	ref_rx_pkts = rx_pkts;
>  	for (nb_pkts_received = 0;
> @@ -210,5 +204,11 @@ virtio_recv_pkts_vec(void *rx_queue,
>  	for (nb_used = 0; nb_used < nb_pkts_received; nb_used++)
>  		virtio_update_packet_stats(&rxvq->stats, ref_rx_pkts[nb_used]);
> 
> +	if (vq->vq_free_cnt >= RTE_VIRTIO_VPMD_RX_REARM_THRESH) {
> +		virtio_rxq_rearm_vec(rxvq);
> +		if (unlikely(virtqueue_kick_prepare(vq)))
> +			virtqueue_notify(vq);
> +	}
> +
>  	return nb_pkts_received;
>  }
> diff --git a/drivers/net/virtio/virtio_rxtx_simple_sse.c b/drivers/net/virtio/virtio_rxtx_simple_sse.c
> index ff4eba33d6..2e17f9d1f2 100644
> --- a/drivers/net/virtio/virtio_rxtx_simple_sse.c
> +++ b/drivers/net/virtio/virtio_rxtx_simple_sse.c
> @@ -100,12 +100,6 @@ virtio_recv_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
> 
>  	rte_prefetch0(rused);
> 
> -	if (vq->vq_free_cnt >= RTE_VIRTIO_VPMD_RX_REARM_THRESH) {
> -		virtio_rxq_rearm_vec(rxvq);
> -		if (unlikely(virtqueue_kick_prepare(vq)))
> -			virtqueue_notify(vq);
> -	}
> -
>  	nb_total = nb_used;
>  	ref_rx_pkts = rx_pkts;
>  	for (nb_pkts_received = 0;
> @@ -194,5 +188,11 @@ virtio_recv_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
>  	for (nb_used = 0; nb_used < nb_pkts_received; nb_used++)
>  		virtio_update_packet_stats(&rxvq->stats, ref_rx_pkts[nb_used]);
> 
> +	if (vq->vq_free_cnt >= RTE_VIRTIO_VPMD_RX_REARM_THRESH) {
> +		virtio_rxq_rearm_vec(rxvq);
> +		if (unlikely(virtqueue_kick_prepare(vq)))
> +			virtqueue_notify(vq);
> +	}
> +
>  	return nb_pkts_received;
>  }
> --
> 2.25.1