Re: [PATCH v5 19/34] net/ixgbe: add a desc done function

["Burakov, Anatoly" <anatoly.burakov@intel.com>]

On 6/6/2025 7:08 PM, Anatoly Burakov wrote:
> Add a function to check DD bit status, and use it everywhere we do these
> checks.
> 
> Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
> ---
> 
> Notes:
>      v5:
>      - Add this commit
> 
>   drivers/net/intel/ixgbe/ixgbe_rxtx.c            |  8 ++------
>   drivers/net/intel/ixgbe/ixgbe_rxtx_vec_common.c |  4 +---
>   drivers/net/intel/ixgbe/ixgbe_rxtx_vec_common.h | 12 +++++++++---
>   3 files changed, 12 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/net/intel/ixgbe/ixgbe_rxtx.c b/drivers/net/intel/ixgbe/ixgbe_rxtx.c
> index 5f0aedb4cd..50060ce64e 100644
> --- a/drivers/net/intel/ixgbe/ixgbe_rxtx.c
> +++ b/drivers/net/intel/ixgbe/ixgbe_rxtx.c
> @@ -118,13 +118,11 @@ static __rte_always_inline int
>   ixgbe_tx_free_bufs(struct ci_tx_queue *txq)
>   {
>   	struct ci_tx_entry *txep;
> -	uint32_t status;
>   	int i, nb_free = 0;
>   	struct rte_mbuf *m, *free[RTE_IXGBE_TX_MAX_FREE_BUF_SZ];
>   
>   	/* check DD bit on threshold descriptor */
> -	status = txq->ixgbe_tx_ring[txq->tx_next_dd].wb.status;
> -	if (!(status & rte_cpu_to_le_32(IXGBE_ADVTXD_STAT_DD)))
> +	if (!ixgbe_tx_desc_done(txq, txq->tx_next_dd))
>   		return 0;
>   
>   	/*
> @@ -3412,7 +3410,6 @@ int
>   ixgbe_dev_tx_descriptor_status(void *tx_queue, uint16_t offset)
>   {
>   	struct ci_tx_queue *txq = tx_queue;
> -	volatile uint32_t *status;
>   	uint32_t desc;
>   
>   	if (unlikely(offset >= txq->nb_tx_desc))
> @@ -3428,8 +3425,7 @@ ixgbe_dev_tx_descriptor_status(void *tx_queue, uint16_t offset)
>   			desc -= txq->nb_tx_desc;
>   	}
>   
> -	status = &txq->ixgbe_tx_ring[desc].wb.status;
> -	if (*status & rte_cpu_to_le_32(IXGBE_ADVTXD_STAT_DD))
> +	if (ixgbe_tx_desc_done(txq, desc))
>   		return RTE_ETH_TX_DESC_DONE;
>   
>   	return RTE_ETH_TX_DESC_FULL;
> diff --git a/drivers/net/intel/ixgbe/ixgbe_rxtx_vec_common.c b/drivers/net/intel/ixgbe/ixgbe_rxtx_vec_common.c
> index cf6d3e4914..707dc7f5f9 100644
> --- a/drivers/net/intel/ixgbe/ixgbe_rxtx_vec_common.c
> +++ b/drivers/net/intel/ixgbe/ixgbe_rxtx_vec_common.c
> @@ -215,7 +215,6 @@ ixgbe_recycle_tx_mbufs_reuse_vec(void *tx_queue,
>   	struct ci_tx_entry *txep;
>   	struct rte_mbuf **rxep;
>   	int i, n;
> -	uint32_t status;
>   	uint16_t nb_recycle_mbufs;
>   	uint16_t avail = 0;
>   	uint16_t mbuf_ring_size = recycle_rxq_info->mbuf_ring_size;
> @@ -232,8 +231,7 @@ ixgbe_recycle_tx_mbufs_reuse_vec(void *tx_queue,
>   		return 0;
>   
>   	/* check DD bits on threshold descriptor */
> -	status = txq->ixgbe_tx_ring[txq->tx_next_dd].wb.status;
> -	if (!(status & IXGBE_ADVTXD_STAT_DD))
> +	if (!ixgbe_tx_desc_done(txq, txq->tx_next_dd))
>   		return 0;
>   
>   	n = txq->tx_rs_thresh;
> diff --git a/drivers/net/intel/ixgbe/ixgbe_rxtx_vec_common.h b/drivers/net/intel/ixgbe/ixgbe_rxtx_vec_common.h
> index 4678a5dfd9..56e13b4125 100644
> --- a/drivers/net/intel/ixgbe/ixgbe_rxtx_vec_common.h
> +++ b/drivers/net/intel/ixgbe/ixgbe_rxtx_vec_common.h
> @@ -25,19 +25,25 @@ void ixgbe_recycle_rx_descriptors_refill_vec(void *rx_queue, uint16_t nb_mbufs);
>   uint16_t ixgbe_recycle_tx_mbufs_reuse_vec(void *tx_queue,
>   		struct rte_eth_recycle_rxq_info *recycle_rxq_info);
>   
> +static inline int
> +ixgbe_tx_desc_done(struct ci_tx_queue *txq, uint16_t idx)
> +{
> +	const uint32_t status = txq->ixgbe_tx_ring[idx].wb.status;
> +
> +	return !!(status & rte_cpu_to_le_32(IXGBE_ADVTXD_STAT_DD));
> +}
> +

This causes compilation errors down the line because vec_common isn't 
included by drivers that don't support vector driver, so I'll move this 
to ixgbe_rxtx.h in v6.

(alternatively, we can keep the stubs and not do conditional inclusion 
of vector code headers)

-- 
Thanks,
Anatoly