Re: [dpdk-dev] [PATCH 2/4] net/i40e: cleanup Tx buffers

["Gavin Hu (Arm Technology China)" <Gavin.Hu@arm.com>]

> -----Original Message-----
> From: dev <dev-bounces@dpdk.org> On Behalf Of Di ChenxuX
> Sent: Thursday, September 26, 2019 5:30 PM
> To: dev@dpdk.org
> Cc: qiming.yang@intel.com; Di ChenxuX <chenxux.di@intel.com>
> Subject: [dpdk-dev] [PATCH 2/4] net/i40e: cleanup Tx buffers
> 
> Add support to the i40e driver for the API rte_eth_tx_done_cleanup
>  to force free consumed buffers on Tx ring.
> 
> Signed-off-by: Di ChenxuX <chenxux.di@intel.com>
> ---
>  drivers/net/i40e/i40e_ethdev.c    |  1 +
>  drivers/net/i40e/i40e_ethdev_vf.c |  1 +
>  drivers/net/i40e/i40e_rxtx.c      | 42 +++++++++++++++++++++++++++++++
>  drivers/net/i40e/i40e_rxtx.h      |  1 +
>  4 files changed, 45 insertions(+)
> 
> diff --git a/drivers/net/i40e/i40e_ethdev.c b/drivers/net/i40e/i40e_ethdev.c
> index 4e40b7ab5..cf35fb5da 100644
> --- a/drivers/net/i40e/i40e_ethdev.c
> +++ b/drivers/net/i40e/i40e_ethdev.c
> @@ -509,6 +509,7 @@ static const struct eth_dev_ops i40e_eth_dev_ops =
> {
>  	.mac_addr_set                 = i40e_set_default_mac_addr,
>  	.mtu_set                      = i40e_dev_mtu_set,
>  	.tm_ops_get                   = i40e_tm_ops_get,
> +	.tx_done_cleanup              = i40e_tx_done_cleanup,
>  };
> 
>  /* store statistics names and its offset in stats structure */
> diff --git a/drivers/net/i40e/i40e_ethdev_vf.c
> b/drivers/net/i40e/i40e_ethdev_vf.c
> index c77b30c54..b462a9d8c 100644
> --- a/drivers/net/i40e/i40e_ethdev_vf.c
> +++ b/drivers/net/i40e/i40e_ethdev_vf.c
> @@ -215,6 +215,7 @@ static const struct eth_dev_ops
> i40evf_eth_dev_ops = {
>  	.rss_hash_conf_get    = i40evf_dev_rss_hash_conf_get,
>  	.mtu_set              = i40evf_dev_mtu_set,
>  	.mac_addr_set         = i40evf_set_default_mac_addr,
> +	.tx_done_cleanup      = i40e_tx_done_cleanup,
>  };
> 
>  /*
> diff --git a/drivers/net/i40e/i40e_rxtx.c b/drivers/net/i40e/i40e_rxtx.c
> index 692c3bab4..29793a1b7 100644
> --- a/drivers/net/i40e/i40e_rxtx.c
> +++ b/drivers/net/i40e/i40e_rxtx.c
> @@ -1416,6 +1416,8 @@ i40e_xmit_pkts_vec(void *tx_queue, struct
> rte_mbuf **tx_pkts,
>  			break;
>  	}
> 
> +	//eth_i40e_tx_done_cleanup(tx_queue,5);
> +
>  	return nb_tx;
>  }
> 
> @@ -2467,6 +2469,46 @@ i40e_tx_queue_release_mbufs(struct
> i40e_tx_queue *txq)
>  	}
>  }
> 
> +int i40e_tx_done_cleanup(void *txq, uint32_t free_cnt)
> +{
> +	struct i40e_tx_queue *q = (struct i40e_tx_queue *)txq;
> +	struct i40e_tx_entry *sw_ring;
> +	uint16_t tx_id;    /* Current segment being processed. */
> +	uint16_t tx_cleaned;
> +
> +	int count = 0;
uint32_t is better, then you will not get trouble into a negative value.
> +
> +	if (q == NULL)
> +		return -ENODEV;
> +
> +	sw_ring = q->sw_ring;
> +	tx_cleaned = q->last_desc_cleaned;
> +	tx_id = sw_ring[q->last_desc_cleaned].next_id;
> +	if ((q->tx_ring[tx_id].cmd_type_offset_bsz &
> +
> 	rte_cpu_to_le_64(I40E_TXD_QW1_DTYPE_MASK)) !=
> +
> 	rte_cpu_to_le_64(I40E_TX_DESC_DTYPE_DESC_DONE))
> +		return 0;
> +
> +	do {
> +		if (sw_ring[tx_id].mbuf == NULL)
> +			break;
> +
> +		rte_pktmbuf_free_seg(sw_ring[tx_id].mbuf);
> +		sw_ring[tx_id].mbuf = NULL;
> +		sw_ring[tx_id].last_id = tx_id;
> +
> +		/* Move to next segemnt. */
> +		tx_cleaned = tx_id;
> +		tx_id = sw_ring[tx_id].next_id;
> +		count++;
> +	} while (count != (int)free_cnt);
This force conversation is not needed if "count" declared as uint32_t above.
/Gavin
> +
> +	q->nb_tx_free += (uint16_t)count;
> +	q->last_desc_cleaned = tx_cleaned;
> +
> +	return count;
> +}
> +
>  void
>  i40e_reset_tx_queue(struct i40e_tx_queue *txq)
>  {
> diff --git a/drivers/net/i40e/i40e_rxtx.h b/drivers/net/i40e/i40e_rxtx.h
> index 3fc619af9..1a70eda2c 100644
> --- a/drivers/net/i40e/i40e_rxtx.h
> +++ b/drivers/net/i40e/i40e_rxtx.h
> @@ -204,6 +204,7 @@ void i40e_dev_free_queues(struct rte_eth_dev
> *dev);
>  void i40e_reset_rx_queue(struct i40e_rx_queue *rxq);
>  void i40e_reset_tx_queue(struct i40e_tx_queue *txq);
>  void i40e_tx_queue_release_mbufs(struct i40e_tx_queue *txq);
> +int i40e_tx_done_cleanup(void *txq, uint32_t free_cnt);
>  int i40e_alloc_rx_queue_mbufs(struct i40e_rx_queue *rxq);
>  void i40e_rx_queue_release_mbufs(struct i40e_rx_queue *rxq);
> 
> --
> 2.17.1