[dpdk-dev] [PATCH v1] ixgbe/vector: add rxd 2^n check to avoid mbuf leak

[Bruce Richardson]

On Mon, Mar 02, 2015 at 09:28:24PM +0800, Cunming Liang wrote:
> The mbuf leak happens when the assigned number of rx descriptor is not power of 2.
> As it's presumed on vpmd rx(for rx_tail wrap), adding condition check to prevent it.
> The root cause reference code in *_recv_raw_pkts_vec* as below.
> "rxq->rx_tail = (uint16_t)(rxq->rx_tail & (rxq->nb_rx_desc - 1));".
> 
> Reported-by: Stephen Hemminger <stephen at networkplumber.org>
> Signed-off-by: Cunming Liang <cunming.liang at intel.com>
Acked-by: Bruce Richardson <bruce.richardson at intel.com>
> ---
>  The issue was reported in http://www.dpdk.org/ml/archives/dev/2015-February/014127.html
> 
>  lib/librte_pmd_ixgbe/ixgbe_rxtx.c | 51 ++++++++++++++-------------------------
>  1 file changed, 18 insertions(+), 33 deletions(-)
> 
> diff --git a/lib/librte_pmd_ixgbe/ixgbe_rxtx.c b/lib/librte_pmd_ixgbe/ixgbe_rxtx.c
> index 3059375..9ecf3e5 100644
> --- a/lib/librte_pmd_ixgbe/ixgbe_rxtx.c
> +++ b/lib/librte_pmd_ixgbe/ixgbe_rxtx.c
> @@ -2257,7 +2257,8 @@ ixgbe_dev_rx_queue_setup(struct rte_eth_dev *dev,
>  			     rxq->port_id, rxq->queue_id);
>  		dev->rx_pkt_burst = ixgbe_recv_pkts_bulk_alloc;
>  #ifdef RTE_IXGBE_INC_VECTOR
> -		if (!ixgbe_rx_vec_condition_check(dev)) {
> +		if (!ixgbe_rx_vec_condition_check(dev) &&
> +		    (rte_is_power_of_2(nb_desc))) {
>  			PMD_INIT_LOG(INFO, "Vector rx enabled, please make "
>  				     "sure RX burst size no less than 32.");
>  			dev->rx_pkt_burst = ixgbe_recv_pkts_vec;
> @@ -3639,31 +3640,23 @@ ixgbe_dev_rx_init(struct rte_eth_dev *dev)
>  		buf_size = (uint16_t) ((srrctl & IXGBE_SRRCTL_BSIZEPKT_MASK) <<
>  				       IXGBE_SRRCTL_BSIZEPKT_SHIFT);
>  
> -		/* It adds dual VLAN length for supporting dual VLAN */
> -		if ((dev->data->dev_conf.rxmode.max_rx_pkt_len +
> +		if (dev->data->dev_conf.rxmode.enable_scatter ||
> +		    /* It adds dual VLAN length for supporting dual VLAN */
> +		    (dev->data->dev_conf.rxmode.max_rx_pkt_len +
>  				2 * IXGBE_VLAN_TAG_SIZE) > buf_size){
>  			if (!dev->data->scattered_rx)
>  				PMD_INIT_LOG(DEBUG, "forcing scatter mode");
>  			dev->data->scattered_rx = 1;
>  #ifdef RTE_IXGBE_INC_VECTOR
> -			dev->rx_pkt_burst = ixgbe_recv_scattered_pkts_vec;
> -#else
> -			dev->rx_pkt_burst = ixgbe_recv_scattered_pkts;
> +			if (rte_is_power_of_2(rxq->nb_rx_desc))
> +				dev->rx_pkt_burst =
> +					ixgbe_recv_scattered_pkts_vec;
> +			else
>  #endif
> +				dev->rx_pkt_burst = ixgbe_recv_scattered_pkts;
>  		}
>  	}
>  
> -	if (dev->data->dev_conf.rxmode.enable_scatter) {
> -		if (!dev->data->scattered_rx)
> -			PMD_INIT_LOG(DEBUG, "forcing scatter mode");
> -#ifdef RTE_IXGBE_INC_VECTOR
> -		dev->rx_pkt_burst = ixgbe_recv_scattered_pkts_vec;
> -#else
> -		dev->rx_pkt_burst = ixgbe_recv_scattered_pkts;
> -#endif
> -		dev->data->scattered_rx = 1;
> -	}
> -
>  	/*
>  	 * Device configured with multiple RX queues.
>  	 */
> @@ -4156,17 +4149,20 @@ ixgbevf_dev_rx_init(struct rte_eth_dev *dev)
>  		buf_size = (uint16_t) ((srrctl & IXGBE_SRRCTL_BSIZEPKT_MASK) <<
>  				       IXGBE_SRRCTL_BSIZEPKT_SHIFT);
>  
> -		/* It adds dual VLAN length for supporting dual VLAN */
> -		if ((dev->data->dev_conf.rxmode.max_rx_pkt_len +
> +		if (dev->data->dev_conf.rxmode.enable_scatter ||
> +		    /* It adds dual VLAN length for supporting dual VLAN */
> +		    (dev->data->dev_conf.rxmode.max_rx_pkt_len +
>  				2 * IXGBE_VLAN_TAG_SIZE) > buf_size) {
>  			if (!dev->data->scattered_rx)
>  				PMD_INIT_LOG(DEBUG, "forcing scatter mode");
>  			dev->data->scattered_rx = 1;
>  #ifdef RTE_IXGBE_INC_VECTOR
> -			dev->rx_pkt_burst = ixgbe_recv_scattered_pkts_vec;
> -#else
> -			dev->rx_pkt_burst = ixgbe_recv_scattered_pkts;
> +			if (rte_is_power_of_2(rxq->nb_rx_desc))
> +				dev->rx_pkt_burst =
> +					ixgbe_recv_scattered_pkts_vec;
> +			else
>  #endif
> +				dev->rx_pkt_burst = ixgbe_recv_scattered_pkts;
>  		}
>  	}
>  
> @@ -4184,17 +4180,6 @@ ixgbevf_dev_rx_init(struct rte_eth_dev *dev)
>  		IXGBE_PSRTYPE_RQPL_SHIFT;
>  	IXGBE_WRITE_REG(hw, IXGBE_VFPSRTYPE, psrtype);
>  
> -	if (dev->data->dev_conf.rxmode.enable_scatter) {
> -		if (!dev->data->scattered_rx)
> -			PMD_INIT_LOG(DEBUG, "forcing scatter mode");
> -#ifdef RTE_IXGBE_INC_VECTOR
> -		dev->rx_pkt_burst = ixgbe_recv_scattered_pkts_vec;
> -#else
> -		dev->rx_pkt_burst = ixgbe_recv_scattered_pkts;
> -#endif
> -		dev->data->scattered_rx = 1;
> -	}
> -
>  	return 0;
>  }
>  
> -- 
> 1.8.1.4
>