Re: [PATCH v3 4/6] net/intel: add AVX2 Support for TxPP

[Bruce Richardson <bruce.richardson@intel.com>]

On Sun, Jun 08, 2025 at 11:32:21AM +0000, Soumyadeep Hore wrote:
> Tx Time based queues are supported using AVX2 vector.
> 
> Signed-off-by: Soumyadeep Hore <soumyadeep.hore@intel.com>
> ---
>  drivers/net/intel/ice/ice_rxtx_vec_avx2.c   | 135 +++++++++++++++++++-
>  drivers/net/intel/ice/ice_rxtx_vec_common.h |  17 +++
>  2 files changed, 151 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/intel/ice/ice_rxtx_vec_avx2.c b/drivers/net/intel/ice/ice_rxtx_vec_avx2.c
> index 0c54b325c6..bd2a277730 100644
> --- a/drivers/net/intel/ice/ice_rxtx_vec_avx2.c
> +++ b/drivers/net/intel/ice/ice_rxtx_vec_avx2.c
> @@ -848,6 +848,129 @@ ice_vtx(volatile struct ice_tx_desc *txdp,
>  	}
>  }
>  
> +static __rte_always_inline void
> +ice_vts1(volatile struct ice_ts_desc *ts, struct rte_mbuf *pkt,
> +		uint16_t tx_tail, uint16_t nb_tx_desc, int ts_offset)
> +{
> +	ts->tx_desc_idx_tstamp = ice_get_ts_queue_desc(pkt,
> +						tx_tail, nb_tx_desc, ts_offset);
> +}
> +
> +static __rte_always_inline void
> +ice_vts4(volatile struct ice_ts_desc *ts, struct rte_mbuf **pkt,
> +	uint16_t nb_pkts, uint16_t tx_tail, uint16_t nb_tx_desc,
> +	int ts_offset)
> +{
> +	uint16_t tx_id;
> +
> +	for (; nb_pkts > 3; ts += 4, pkt += 4, nb_pkts -= 4,
> +			tx_tail += 4) {
> +		tx_id = tx_tail + 4;
> +		uint32_t ts_dsc3 = ice_get_ts_queue_desc(pkt[3],
> +						tx_id, nb_tx_desc, ts_offset);
> +		tx_id = tx_tail + 3;
> +		uint32_t ts_dsc2 = ice_get_ts_queue_desc(pkt[2],
> +						tx_id, nb_tx_desc, ts_offset);
> +		tx_id = tx_tail + 2;
> +		uint32_t ts_dsc1 = ice_get_ts_queue_desc(pkt[1],
> +						tx_id, nb_tx_desc, ts_offset);
> +		tx_id = tx_tail + 1;
> +		uint32_t ts_dsc0 = ice_get_ts_queue_desc(pkt[0],
> +						tx_id, nb_tx_desc, ts_offset);
> +		__m128i desc0_3 = _mm_set_epi32(ts_dsc3, ts_dsc2,
> +						ts_dsc1, ts_dsc0);
> +		_mm_store_si128(RTE_CAST_PTR(void *, ts), desc0_3);
> +	}
> +
> +	/* do any last ones */
> +	while (nb_pkts) {
> +		tx_tail++;
> +		ice_vts1(ts, *pkt, tx_tail, nb_tx_desc, ts_offset);
> +		ts++, pkt++, nb_pkts--;
> +	}
> +}
> +
> +static __rte_always_inline void
> +ice_vts(volatile struct ice_ts_desc *ts, struct rte_mbuf **pkt,
> +	uint16_t nb_pkts, uint16_t tx_tail, uint16_t nb_tx_desc,
> +	int ts_offset)
> +{
> +	uint16_t tx_id;
> +
> +	for (; nb_pkts > 7; ts += 8, pkt += 8, nb_pkts -= 8,
> +			tx_tail += 8) {
> +		tx_id = tx_tail + 8;
> +		uint32_t ts_dsc7 = ice_get_ts_queue_desc(pkt[7],
> +						tx_id, nb_tx_desc, ts_offset);
> +		tx_id = tx_tail + 7;
> +		uint32_t ts_dsc6 = ice_get_ts_queue_desc(pkt[6],
> +						tx_id, nb_tx_desc, ts_offset);
> +		tx_id = tx_tail + 6;
> +		uint32_t ts_dsc5 = ice_get_ts_queue_desc(pkt[5],
> +						tx_id, nb_tx_desc, ts_offset);
> +		tx_id = tx_tail + 5;
> +		uint32_t ts_dsc4 = ice_get_ts_queue_desc(pkt[4],
> +						tx_id, nb_tx_desc, ts_offset);
> +		tx_id = tx_tail + 4;
> +		uint32_t ts_dsc3 = ice_get_ts_queue_desc(pkt[3],
> +						tx_id, nb_tx_desc, ts_offset);
> +		tx_id = tx_tail + 3;
> +		uint32_t ts_dsc2 = ice_get_ts_queue_desc(pkt[2],
> +						tx_id, nb_tx_desc, ts_offset);
> +		tx_id = tx_tail + 2;
> +		uint32_t ts_dsc1 = ice_get_ts_queue_desc(pkt[1],
> +						tx_id, nb_tx_desc, ts_offset);
> +		tx_id = tx_tail + 1;
> +		uint32_t ts_dsc0 = ice_get_ts_queue_desc(pkt[0],
> +						tx_id, nb_tx_desc, ts_offset);
> +		__m256i desc0_7 = _mm256_set_epi32(ts_dsc7, ts_dsc6,
> +						ts_dsc5, ts_dsc4, ts_dsc3, ts_dsc2,
> +						ts_dsc1, ts_dsc0);
> +		_mm256_storeu_si256(RTE_CAST_PTR(void *, ts), desc0_7);
> +	}
> +
> +	/* do any last ones */
> +	if (nb_pkts)
> +		ice_vts4(ts, pkt, nb_pkts, tx_tail, nb_tx_desc,
> +				ts_offset);
> +}
> +
> +static __rte_always_inline uint16_t
> +ice_xmit_fixed_ts_burst_vec_avx512(struct ci_tx_queue *txq,
> +				struct rte_mbuf **tx_pkts, uint16_t nb_pkts,
> +				uint16_t tx_tail)

Avx512?

> +{
> +	volatile struct ice_ts_desc *ts;
> +	uint16_t n;
> +	uint16_t ts_id;
> +	uint16_t fetch;
> +
> +	ts_id = txq->tsq.ts_tail;
> +	ts = &txq->tsq.ice_ts_ring[ts_id];
> +
> +	n = (uint16_t)(txq->tsq.nb_ts_desc - ts_id);
> +	if (nb_pkts >= n) {
> +		ice_vts(ts, tx_pkts, n, txq->tx_tail, txq->nb_tx_desc,
> +				txq->tsq.ts_offset);
> +		tx_pkts += n;
> +		ts += n;
> +		tx_tail += n;
> +		nb_pkts = (uint16_t)(nb_pkts - n);
> +		ts_id = 0;
> +		ts = &txq->tsq.ice_ts_ring[ts_id];
> +		fetch = txq->tsq.nb_ts_desc - txq->nb_tx_desc;
> +		for (; ts_id < fetch; ts_id++, ts++)
> +			ice_vts1(ts, *tx_pkts, tx_tail + 1,
> +					txq->nb_tx_desc, txq->tsq.ts_offset);
> +	}
> +
> +	ice_vts(ts, tx_pkts, nb_pkts, tx_tail, txq->nb_tx_desc,
> +			txq->tsq.ts_offset);
> +	ts_id = (uint16_t)(ts_id + nb_pkts);
> +
> +	return ts_id;
> +}
> +
>  static __rte_always_inline uint16_t
>  ice_xmit_fixed_burst_vec_avx2(void *tx_queue, struct rte_mbuf **tx_pkts,
>  			      uint16_t nb_pkts, bool offload)
> @@ -856,6 +979,7 @@ ice_xmit_fixed_burst_vec_avx2(void *tx_queue, struct rte_mbuf **tx_pkts,
>  	volatile struct ice_tx_desc *txdp;
>  	struct ci_tx_entry_vec *txep;
>  	uint16_t n, nb_commit, tx_id;
> +	uint16_t ts_id = -1;
>  	uint64_t flags = ICE_TD_CMD;
>  	uint64_t rs = ICE_TX_DESC_CMD_RS | ICE_TD_CMD;
>  
> @@ -875,6 +999,10 @@ ice_xmit_fixed_burst_vec_avx2(void *tx_queue, struct rte_mbuf **tx_pkts,
>  
>  	txq->nb_tx_free = (uint16_t)(txq->nb_tx_free - nb_pkts);
>  
> +	if (txq->tsq.ts_flag > 0)
> +		ts_id = ice_xmit_fixed_ts_burst_vec_avx512(txq,
> +								tx_pkts, nb_commit, tx_id);
> +
>  	n = (uint16_t)(txq->nb_tx_desc - tx_id);
>  	if (nb_commit >= n) {
>  		ci_tx_backlog_entry_vec(txep, tx_pkts, n);
> @@ -910,7 +1038,12 @@ ice_xmit_fixed_burst_vec_avx2(void *tx_queue, struct rte_mbuf **tx_pkts,
>  
>  	txq->tx_tail = tx_id;
>  
> -	ICE_PCI_REG_WC_WRITE(txq->qtx_tail, txq->tx_tail);
> +	if (txq->tsq.ts_flag > 0) {
> +		ICE_PCI_REG_WC_WRITE(txq->qtx_tail, ts_id);
> +		txq->tsq.ts_tail = ts_id;
> +	} else {
> +		ICE_PCI_REG_WC_WRITE(txq->qtx_tail, txq->tx_tail);
> +	}
>  

Rather than having two branches in this function, if you move the call to
ice_xmit_fixed_ts_burst_vec_avx* down to take place after the regular
descriptor enqueue, you can do it in one. The timestamp enqueues seem
independent of the regular ones.

>  	return nb_pkts;
>  }
> diff --git a/drivers/net/intel/ice/ice_rxtx_vec_common.h b/drivers/net/intel/ice/ice_rxtx_vec_common.h
> index 7933c26366..9166a0408a 100644
> --- a/drivers/net/intel/ice/ice_rxtx_vec_common.h
> +++ b/drivers/net/intel/ice/ice_rxtx_vec_common.h
> @@ -215,4 +215,21 @@ ice_txd_enable_offload(struct rte_mbuf *tx_pkt,
>  
>  	*txd_hi |= ((uint64_t)td_cmd) << ICE_TXD_QW1_CMD_S;
>  }
> +
> +static inline uint32_t
> +ice_get_ts_queue_desc(struct rte_mbuf *pkt, uint16_t tx_tail,
> +					uint16_t nb_tx_desc, int ts_offset)
> +{
> +	uint64_t txtime;
> +	uint32_t tstamp, ts_desc;
> +
> +	tx_tail = (tx_tail > nb_tx_desc) ? (tx_tail - nb_tx_desc) :
> +			tx_tail;
> +	txtime = *RTE_MBUF_DYNFIELD(pkt, ts_offset, uint64_t *);
> +	tstamp = (uint32_t)(txtime % NS_PER_S) >>
> +			ICE_TXTIME_CTX_RESOLUTION_128NS;
> +	ts_desc = rte_cpu_to_le_32(FIELD_PREP(ICE_TXTIME_TX_DESC_IDX_M,
> +			(tx_tail)) | FIELD_PREP(ICE_TXTIME_STAMP_M, tstamp));
> +	return ts_desc;
> +}
>  #endif
> -- 
> 2.43.0
>