> > > >
> > > > Define specific function implementation for i40e driver.
> > > > Currently, mbufs recycle mode can support 128bit vector path and avx2
> > path.
> > > > And can be enabled both in fast free and no fast free mode.
> > > >
> > > > Suggested-by: Honnappa Nagarahalli <honnappa.nagaraha...@arm.com>
> > > > Signed-off-by: Feifei Wang <feifei.wa...@arm.com>
> > > > Reviewed-by: Ruifeng Wang <ruifeng.w...@arm.com>
> > > > Reviewed-by: Honnappa Nagarahalli <honnappa.nagaraha...@arm.com>
> > > > ---
> > > > drivers/net/i40e/i40e_ethdev.c | 1 +
> > > > drivers/net/i40e/i40e_ethdev.h | 2 +
> > > > .../net/i40e/i40e_recycle_mbufs_vec_common.c | 147
> > > > ++++++++++++++++++
> > > > drivers/net/i40e/i40e_rxtx.c | 32 ++++
> > > > drivers/net/i40e/i40e_rxtx.h | 4 +
> > > > drivers/net/i40e/meson.build | 1 +
> > > > 6 files changed, 187 insertions(+)
> > > > create mode 100644 drivers/net/i40e/i40e_recycle_mbufs_vec_common.c
> > > >
> > > > diff --git a/drivers/net/i40e/i40e_ethdev.c
> > > > b/drivers/net/i40e/i40e_ethdev.c index 8271bbb394..50ba9aac94 100644
> > > > --- a/drivers/net/i40e/i40e_ethdev.c
> > > > +++ b/drivers/net/i40e/i40e_ethdev.c
> > > > @@ -496,6 +496,7 @@ static const struct eth_dev_ops i40e_eth_dev_ops
> > = {
> > > > .flow_ops_get = i40e_dev_flow_ops_get,
> > > > .rxq_info_get = i40e_rxq_info_get,
> > > > .txq_info_get = i40e_txq_info_get,
> > > > + .recycle_rxq_info_get = i40e_recycle_rxq_info_get,
> > > > .rx_burst_mode_get = i40e_rx_burst_mode_get,
> > > > .tx_burst_mode_get = i40e_tx_burst_mode_get,
> > > > .timesync_enable = i40e_timesync_enable,
> > > > diff --git a/drivers/net/i40e/i40e_ethdev.h
> > > > b/drivers/net/i40e/i40e_ethdev.h index 6f65d5e0ac..af758798e1 100644
> > > > --- a/drivers/net/i40e/i40e_ethdev.h
> > > > +++ b/drivers/net/i40e/i40e_ethdev.h
> > > > @@ -1355,6 +1355,8 @@ void i40e_rxq_info_get(struct rte_eth_dev
> > > > *dev, uint16_t queue_id,
> > > > struct rte_eth_rxq_info *qinfo);
> > > > void i40e_txq_info_get(struct rte_eth_dev *dev, uint16_t queue_id,
> > > > struct rte_eth_txq_info *qinfo);
> > > > +void i40e_recycle_rxq_info_get(struct rte_eth_dev *dev, uint16_t
> > queue_id,
> > > > + struct rte_eth_recycle_rxq_info *recycle_rxq_info);
> > > > int i40e_rx_burst_mode_get(struct rte_eth_dev *dev, uint16_t queue_id,
> > > > struct rte_eth_burst_mode *mode); int
> > > > i40e_tx_burst_mode_get(struct rte_eth_dev *dev, uint16_t queue_id,
> > > > diff -- git a/drivers/net/i40e/i40e_recycle_mbufs_vec_common.c
> > > > b/drivers/net/i40e/i40e_recycle_mbufs_vec_common.c
> > > > new file mode 100644
> > > > index 0000000000..5663ecccde
> > > > --- /dev/null
> > > > +++ b/drivers/net/i40e/i40e_recycle_mbufs_vec_common.c
> > > > @@ -0,0 +1,147 @@
> > > > +/* SPDX-License-Identifier: BSD-3-Clause
> > > > + * Copyright (c) 2023 Arm Limited.
> > > > + */
> > > > +
> > > > +#include <stdint.h>
> > > > +#include <ethdev_driver.h>
> > > > +
> > > > +#include "base/i40e_prototype.h"
> > > > +#include "base/i40e_type.h"
> > > > +#include "i40e_ethdev.h"
> > > > +#include "i40e_rxtx.h"
> > > > +
> > > > +#pragma GCC diagnostic ignored "-Wcast-qual"
> > > > +
> > > > +void
> > > > +i40e_recycle_rx_descriptors_refill_vec(void *rx_queue, uint16_t
> > > > +nb_mbufs) {
> > > > + struct i40e_rx_queue *rxq = rx_queue;
> > > > + struct i40e_rx_entry *rxep;
> > > > + volatile union i40e_rx_desc *rxdp;
> > > > + uint16_t rx_id;
> > > > + uint64_t paddr;
> > > > + uint64_t dma_addr;
> > > > + uint16_t i;
> > > > +
> > > > + rxdp = rxq->rx_ring + rxq->rxrearm_start;
> > > > + rxep = &rxq->sw_ring[rxq->rxrearm_start];
> > > > +
> > > > + for (i = 0; i < nb_mbufs; i++) {
> > > > + /* Initialize rxdp descs. */
> > > > + paddr = (rxep[i].mbuf)->buf_iova +
> > > > RTE_PKTMBUF_HEADROOM;
> > > > + dma_addr = rte_cpu_to_le_64(paddr);
> > > > + /* flush desc with pa dma_addr */
> > > > + rxdp[i].read.hdr_addr = 0;
> > > > + rxdp[i].read.pkt_addr = dma_addr;
> > > > + }
> > > > +
> > > > + /* Update the descriptor initializer index */
> > > > + rxq->rxrearm_start += nb_mbufs;
> > > > + rx_id = rxq->rxrearm_start - 1;
> > > > +
> > > > + if (unlikely(rxq->rxrearm_start >= rxq->nb_rx_desc)) {
> > > > + rxq->rxrearm_start = 0;
> > > > + rx_id = rxq->nb_rx_desc - 1;
> > > > + }
> > > > +
> > > > + rxq->rxrearm_nb -= nb_mbufs;
> > > > +
> > > > + rte_io_wmb();
> > > > + /* Update the tail pointer on the NIC */
> > > > + I40E_PCI_REG_WRITE_RELAXED(rxq->qrx_tail, rx_id); }
> > > > +
> > > > +uint16_t
> > > > +i40e_recycle_tx_mbufs_reuse_vec(void *tx_queue,
> > > > + struct rte_eth_recycle_rxq_info *recycle_rxq_info) {
> > > > + struct i40e_tx_queue *txq = tx_queue;
> > > > + struct i40e_tx_entry *txep;
> > > > + struct rte_mbuf **rxep;
> > > > + int i, n;
> > > > + uint16_t nb_recycle_mbufs;
> > > > + uint16_t avail = 0;
> > > > + uint16_t mbuf_ring_size = recycle_rxq_info->mbuf_ring_size;
> > > > + uint16_t mask = recycle_rxq_info->mbuf_ring_size - 1;
> > > > + uint16_t refill_requirement =
> > > > recycle_rxq_info->refill_requirement;
> > > > + uint16_t refill_head = *recycle_rxq_info->refill_head;
> > > > + uint16_t receive_tail = *recycle_rxq_info->receive_tail;
> > > > +
> > > > + /* Get available recycling Rx buffers. */
> > > > + avail = (mbuf_ring_size - (refill_head - receive_tail)) & mask;
> > > > +
> > > > + /* Check Tx free thresh and Rx available space. */
> > > > + if (txq->nb_tx_free > txq->tx_free_thresh || avail <=
> > > > txq->tx_rs_thresh)
> > > > + return 0;
> > > > +
> > > > + /* check DD bits on threshold descriptor */
> > > > + if ((txq->tx_ring[txq->tx_next_dd].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;
> > > > +
> > > > + n = txq->tx_rs_thresh;
> > > > + nb_recycle_mbufs = n;
> > > > +
> > > > + /* Mbufs recycle mode can only support no ring buffer wrapping
> > > > around.
> > > > + * Two case for this:
> > > > + *
> > > > + * case 1: The refill head of Rx buffer ring needs to be
> > > > aligned with
> > > > + * mbuf ring size. In this case, the number of Tx freeing
> > > > buffers
> > > > + * should be equal to refill_requirement.
> > > > + *
> > > > + * case 2: The refill head of Rx ring buffer does not need to
> > > > be aligned
> > > > + * with mbuf ring size. In this case, the update of refill head
> > > > can not
> > > > + * exceed the Rx mbuf ring size.
> > > > + */
> > > > + if (refill_requirement != n ||
> > > > + (!refill_requirement && (refill_head + n >
> > > > mbuf_ring_size)))
> > > > + return 0;
> > > > +
> > > > + /* First buffer to free from S/W ring is at index
> > > > + * tx_next_dd - (tx_rs_thresh-1).
> > > > + */
> > > > + txep = &txq->sw_ring[txq->tx_next_dd - (n - 1)];
> > > > + rxep = recycle_rxq_info->mbuf_ring;
> > > > + rxep += refill_head;
> > > > +
> > > > + if (txq->offloads & RTE_ETH_TX_OFFLOAD_MBUF_FAST_FREE) {
> > > > + /* Avoid txq contains buffers from unexpected mempool.
> > > > */
> > > > + if (unlikely(recycle_rxq_info->mp
> > > > + != txep[0].mbuf->pool))
> > > > + return 0;
> > > > +
> > > > + /* Directly put mbufs from Tx to Rx. */
> > > > + for (i = 0; i < n; i++)
> > > > + rxep[i] = txep[i].mbuf;
> > > > + } else {
> > > > + for (i = 0; i < n; i++) {
> > > > + rxep[i] = rte_pktmbuf_prefree_seg(txep[i].mbuf);
> > > > +
> > > > + /* If Tx buffers are not the last reference or
> > > > from
> > > > + * unexpected mempool, previous copied buffers
> > > > are
> > > > + * considered as invalid.
> > > > + */
> > > > + if (unlikely((rxep[i] == NULL &&
> > > > refill_requirement) ||
> > > [Konstantin]
> > > Could you pls remind me why it is ok to have rxep[i]==NULL when
> > > refill_requirement is not set?
> > >
> > > If reill_requirement is not zero, it means each tx freed buffer must
> > > be valid and can be put into Rx sw_ring. Then the refill head of Rx
> > > buffer ring can be aligned with mbuf ring size. Briefly speaking the
> > > number
> > of Tx valid freed buffer must be equal to Rx refill_requirement. For
> > example,
> > i40e driver.
> > >
> > > If reill_requirement is zero, it means that the refill head of Rx
> > > buffer ring does not need to be aligned with mbuf ring size, thus if
> > > Tx have n valid freed buffers, we just need to put these n buffers into
> > > Rx sw-
> > ring, and not to be equal to the Rx setting rearm number. For example, mlx5
> > driver.
> > >
> > > In conclusion, above difference is due to pmd drivers have different
> > strategies to update their Rx rearm(refill) head.
> > > For i40e driver, if rearm_head exceed 1024, it will be set as 0 due to
> > > the
> > number of each rearm is a fixed value by default.
> > > For mlx5 driver. Its rearm_head can exceed 1024, and use mask to achieve
> > real index. Thus its rearm number can be a different value.
> >
> > Ok, but if rte_pktmbuf_prefree_seg(txep[i].mbuf), it means that this mbuf is
> > not free yet and can't be reused.
> > Shouldn't we then set nb_recycle_mbufs = 0 in that case too?
> > Or probably would be enough to skip that mbuf?
> > Might be something like that:
> >
> > for (i = 0, j = 0; i < n; i++) {
> >
> > rxep[j] = rte_pktmbuf_prefree_seg(txep[i].mbuf);
> > if (rxep[j] == NULL || recycle_rxq_info->mp != rxep[j].mbuf->pool)) {
> > if (refill_requirement) {
> > nb_recycle_mbufs = 0;
> > break;
> > }
> > } else
> > j++;
> > }
> >
> > /* now j contains actual number of recycled mbufs */
> >
> > ?
> >
> > >
> > > > + recycle_rxq_info->mp !=
> > > > txep[i].mbuf-
> > > > >pool))
> > > > + nb_recycle_mbufs = 0;
> > > > + }
> > > > + /* If Tx buffers are not the last reference or
> > > > + * from unexpected mempool, all recycled buffers
> > > > + * are put into mempool.
> > > > + */
> > > > + if (nb_recycle_mbufs == 0)
> > > > + for (i = 0; i < n; i++) {
> > > > + if (rxep[i] != NULL)
> > > > + rte_mempool_put(rxep[i]->pool,
> > > > rxep[i]);
> > > > + }
> > > > + }
> > > > +
> [Konstantin] After another thought, it might be easier and cleaner just to:
> if (rxep[j] == NULL || recycle_rxq_info->mp != rxep[j].mbuf->pool)
> nb_recycle_mbufs = 0;
>
> Anyway, from my understanding - if rte_pktmbuf_prefree_seg(mbuf) returns
> NULL, then we can't recycle that mbuf.
>
> [Feifei] Agree with that 'rte_pktmbuf_prefree_seg(mbuf) returns NULL, then we
> can't recycle that mbuf'.
>
> Firstly, we should know for i40e driver, the number of free mbufs is fixed,
> it must equal to 'tx_rs_thresh'
> This means if we start to free Tx mbufs, it cannot be interrupted until the
> given amount of mbufs are freed.
> In the meanwhile, doing prefree operation for a Tx mbuf can be looked at this
> mbuf is freed from this TX sw-ring
> if the API returns NULL. This is due to that call 'prefree_seg' function
> means update the mbuf refcnt.
>
> So let's come back our recycle mbuf case.
> Here we consider that the case if we have 32 mbufs need to be freed, and we
> firstly do the pre-free.
> And then first 8 mbufs is good and return value is not none. But the 9th mbuf
> is bad, its refcnt is more than 1.
> So we just update its refcnt and cannot put it into Rx sw-ring. For Tx
> sw-ring, this mbuf has been freed.
> Then we should continue to do pre-free operation for the next Tx mbufs to
> ensure the given amount of
> mbufs are freed.
>
> Do a conclusion for this, this is because if we start to do pre-free
> operation, the Tx mbuf refcnt value
> maybe changed, so we cannot stop or break until finish all the pre-free
> operation.
>
> Finally, in the case that Rx refill_request is not zero, but the valid mbuf
> amount is less than this value,
> we must put back this Tx mbufs into mempool.
>
> Above is the reason why I do not directly jump out of the loop if some mbuf
> return value is NULL.
Yep, I already realized that it is a bit more complicated and we need to
continue with prefree()
for all packets even when we get NULL in the middle.
Anyway the code has to be changed, right?
>
> > > > + /* Update counters for Tx. */
> > > > + txq->nb_tx_free = (uint16_t)(txq->nb_tx_free +
> > > > txq->tx_rs_thresh);
> > > > + txq->tx_next_dd = (uint16_t)(txq->tx_next_dd +
> > > > txq->tx_rs_thresh);
> > > > + if (txq->tx_next_dd >= txq->nb_tx_desc)
> > > > + txq->tx_next_dd = (uint16_t)(txq->tx_rs_thresh - 1);
> > > > +
> > > > + return nb_recycle_mbufs;
> > > > +}
> > > > diff --git a/drivers/net/i40e/i40e_rxtx.c
> > > > b/drivers/net/i40e/i40e_rxtx.c index b4f65b58fa..a9c9eb331c 100644
> > > > --- a/drivers/net/i40e/i40e_rxtx.c
> > > > +++ b/drivers/net/i40e/i40e_rxtx.c
> > > > @@ -3199,6 +3199,30 @@ i40e_txq_info_get(struct rte_eth_dev *dev,
> > > > uint16_t queue_id,
> > > > qinfo->conf.offloads = txq->offloads; }
> > > >
> > > > +void
> > > > +i40e_recycle_rxq_info_get(struct rte_eth_dev *dev, uint16_t queue_id,
> > > > + struct rte_eth_recycle_rxq_info *recycle_rxq_info) {
> > > > + struct i40e_rx_queue *rxq;
> > > > + struct i40e_adapter *ad =
> > > > + I40E_DEV_PRIVATE_TO_ADAPTER(dev->data->dev_private);
> > > > +
> > > > + rxq = dev->data->rx_queues[queue_id];
> > > > +
> > > > + recycle_rxq_info->mbuf_ring = (void *)rxq->sw_ring;
> > > > + recycle_rxq_info->mp = rxq->mp;
> > > > + recycle_rxq_info->mbuf_ring_size = rxq->nb_rx_desc;
> > > > + recycle_rxq_info->receive_tail = &rxq->rx_tail;
> > > > +
> > > > + if (ad->rx_vec_allowed) {
> > > > + recycle_rxq_info->refill_requirement =
> > > > RTE_I40E_RXQ_REARM_THRESH;
> > > > + recycle_rxq_info->refill_head = &rxq->rxrearm_start;
> > > > + } else {
> > > > + recycle_rxq_info->refill_requirement =
> > > > rxq->rx_free_thresh;
> > > > + recycle_rxq_info->refill_head = &rxq->rx_free_trigger;
> > > > + }
> > > > +}
> > > > +
> > > > #ifdef RTE_ARCH_X86
> > > > static inline bool
> > > > get_avx_supported(bool request_avx512) @@ -3293,6 +3317,8 @@
> > > > i40e_set_rx_function(struct rte_eth_dev *dev)
> > > > dev->rx_pkt_burst = ad->rx_use_avx2 ?
> > > >
> > > > i40e_recv_scattered_pkts_vec_avx2 :
> > > > i40e_recv_scattered_pkts_vec;
> > > > + dev->recycle_rx_descriptors_refill =
> > > > +
> > > > i40e_recycle_rx_descriptors_refill_vec;
> > > > }
> > > > } else {
> > > > if (ad->rx_use_avx512) {
> > > > @@ -3311,9 +3337,12 @@ i40e_set_rx_function(struct rte_eth_dev *dev)
> > > > dev->rx_pkt_burst = ad->rx_use_avx2 ?
> > > > i40e_recv_pkts_vec_avx2 :
> > > > i40e_recv_pkts_vec;
> > > > + dev->recycle_rx_descriptors_refill =
> > > > +
> > > > i40e_recycle_rx_descriptors_refill_vec;
> > > > }
> > > > }
> > > > #else /* RTE_ARCH_X86 */
> > > > + dev->recycle_rx_descriptors_refill =
> > > > +i40e_recycle_rx_descriptors_refill_vec;
> > > > if (dev->data->scattered_rx) {
> > > > PMD_INIT_LOG(DEBUG,
> > > > "Using Vector Scattered Rx (port
> > > > %d).", @@
> > > > -3481,15 +3510,18 @@ i40e_set_tx_function(struct rte_eth_dev *dev)
> > > > dev->tx_pkt_burst = ad->tx_use_avx2 ?
> > > >
> > > > i40e_xmit_pkts_vec_avx2 :
> > > > i40e_xmit_pkts_vec;
> > > > + dev->recycle_tx_mbufs_reuse =
> > > > i40e_recycle_tx_mbufs_reuse_vec;
> > > > }
> > > > #else /* RTE_ARCH_X86 */
> > > > PMD_INIT_LOG(DEBUG, "Using Vector Tx (port
> > > > %d).",
> > > > dev->data->port_id);
> > > > dev->tx_pkt_burst = i40e_xmit_pkts_vec;
> > > > + dev->recycle_tx_mbufs_reuse =
> > > > i40e_recycle_tx_mbufs_reuse_vec;
> > > > #endif /* RTE_ARCH_X86 */
> > > > } else {
> > > > PMD_INIT_LOG(DEBUG, "Simple tx finally be
> > > > used.");
> > > > dev->tx_pkt_burst = i40e_xmit_pkts_simple;
> > > > + dev->recycle_tx_mbufs_reuse =
> > > > i40e_recycle_tx_mbufs_reuse_vec;
> > > > }
> > > > dev->tx_pkt_prepare = i40e_simple_prep_pkts;
> > > > } else {
> > > > diff --git a/drivers/net/i40e/i40e_rxtx.h
> > > > b/drivers/net/i40e/i40e_rxtx.h index a8686224e5..b191f23e1f 100644
> > > > --- a/drivers/net/i40e/i40e_rxtx.h
> > > > +++ b/drivers/net/i40e/i40e_rxtx.h
> > > > @@ -236,6 +236,10 @@ uint32_t i40e_dev_rx_queue_count(void
> > > > *rx_queue); int i40e_dev_rx_descriptor_status(void *rx_queue,
> > > > uint16_t offset); int i40e_dev_tx_descriptor_status(void *tx_queue,
> > > > uint16_t offset);
> > > >
> > > > +uint16_t i40e_recycle_tx_mbufs_reuse_vec(void *tx_queue,
> > > > + struct rte_eth_recycle_rxq_info *recycle_rxq_info); void
> > > > +i40e_recycle_rx_descriptors_refill_vec(void *rx_queue, uint16_t
> > > > +nb_mbufs);
> > > > +
> > > > uint16_t i40e_recv_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
> > > > uint16_t nb_pkts);
> > > > uint16_t i40e_recv_scattered_pkts_vec(void *rx_queue, diff --git
> > > > a/drivers/net/i40e/meson.build b/drivers/net/i40e/meson.build index
> > > > 8e53b87a65..3b1a233c84 100644
> > > > --- a/drivers/net/i40e/meson.build
> > > > +++ b/drivers/net/i40e/meson.build
> > > > @@ -34,6 +34,7 @@ sources = files(
> > > > 'i40e_tm.c',
> > > > 'i40e_hash.c',
> > > > 'i40e_vf_representor.c',
> > > > + 'i40e_recycle_mbufs_vec_common.c',
> > > > 'rte_pmd_i40e.c',
> > > > )
> > > >
> > > > --
> > > > 2.25.1
