[dpdk-dev] net/mlx5: fix wrong use of vector instruction

  Constraint alignment was not respected in Tx.

Fixes: 1d88ba171942 ("net/mlx5: refactor Tx data path")

Signed-off-by: Elad Persiko <eladpe@mellanox.com>
---
 drivers/net/mlx5/mlx5_rxtx.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
  

On 11/1/2016 8:13 AM, Elad Persiko wrote:
> Constraint alignment was not respected in Tx.
> 
> Fixes: 1d88ba171942 ("net/mlx5: refactor Tx data path")
> 
> Signed-off-by: Elad Persiko <eladpe@mellanox.com>
> ---
>  drivers/net/mlx5/mlx5_rxtx.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/mlx5/mlx5_rxtx.c b/drivers/net/mlx5/mlx5_rxtx.c
> index 21164ba..ba8e202 100644
> --- a/drivers/net/mlx5/mlx5_rxtx.c
> +++ b/drivers/net/mlx5/mlx5_rxtx.c
> @@ -309,7 +309,7 @@ mlx5_tx_dbrec(struct txq *txq)
>  	*txq->qp_db = htonl(txq->wqe_ci);
>  	/* Ensure ordering between DB record and BF copy. */
>  	rte_wmb();
> -	rte_mov16(dst, (uint8_t *)data);
> +	memcpy(dst, (uint8_t *)data, 16);
>  	txq->bf_offset ^= (1 << txq->bf_buf_size);
>  }
>  
> @@ -449,7 +449,7 @@ mlx5_tx_burst(void *dpdk_txq, struct rte_mbuf **pkts, uint16_t pkts_n)
>  		wqe->eseg.mss = 0;
>  		wqe->eseg.rsvd2 = 0;
>  		/* Start by copying the Ethernet Header. */
> -		rte_mov16((uint8_t *)raw, (uint8_t *)addr);
> +		memcpy((uint8_t *)raw, ((uint8_t *)addr), 16);
>  		length -= MLX5_WQE_DWORD_SIZE;
>  		addr += MLX5_WQE_DWORD_SIZE;
>  		/* Replace the Ethernet type by the VLAN if necessary. */
> 

CC: Maintainers (Adrien Mazarguil <adrien.mazarguil@6wind.com>)
  

On Tue, Nov 01, 2016 at 08:13:27AM +0000, Elad Persiko wrote:
> Constraint alignment was not respected in Tx.
> 
> Fixes: 1d88ba171942 ("net/mlx5: refactor Tx data path")
> 
> Signed-off-by: Elad Persiko <eladpe@mellanox.com>
> ---
>  drivers/net/mlx5/mlx5_rxtx.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/mlx5/mlx5_rxtx.c b/drivers/net/mlx5/mlx5_rxtx.c
> index 21164ba..ba8e202 100644
> --- a/drivers/net/mlx5/mlx5_rxtx.c
> +++ b/drivers/net/mlx5/mlx5_rxtx.c
> @@ -309,7 +309,7 @@ mlx5_tx_dbrec(struct txq *txq)
>  	*txq->qp_db = htonl(txq->wqe_ci);
>  	/* Ensure ordering between DB record and BF copy. */
>  	rte_wmb();
> -	rte_mov16(dst, (uint8_t *)data);
> +	memcpy(dst, (uint8_t *)data, 16);
>  	txq->bf_offset ^= (1 << txq->bf_buf_size);
>  }
>  
> @@ -449,7 +449,7 @@ mlx5_tx_burst(void *dpdk_txq, struct rte_mbuf **pkts, uint16_t pkts_n)
>  		wqe->eseg.mss = 0;
>  		wqe->eseg.rsvd2 = 0;
>  		/* Start by copying the Ethernet Header. */
> -		rte_mov16((uint8_t *)raw, (uint8_t *)addr);
> +		memcpy((uint8_t *)raw, ((uint8_t *)addr), 16);
>  		length -= MLX5_WQE_DWORD_SIZE;
>  		addr += MLX5_WQE_DWORD_SIZE;
>  		/* Replace the Ethernet type by the VLAN if necessary. */
> -- 
> 1.8.3.1

Acked-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>
  

2016-11-02 16:56, Adrien Mazarguil:
> On Tue, Nov 01, 2016 at 08:13:27AM +0000, Elad Persiko wrote:
> > Constraint alignment was not respected in Tx.
> > 
> > Fixes: 1d88ba171942 ("net/mlx5: refactor Tx data path")
> > 
> > Signed-off-by: Elad Persiko <eladpe@mellanox.com>
> 
> Acked-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>

"wrong use of vector instruction" is the cause, not the issue.
Reworded: "fix buffer alignment in Tx"

It would have been valuable to describe the consequences.

Applied