| Message ID | 20241018-b4-igb_zero_copy-v9-6-da139d78d796@linutronix.de |
|---|---|
| State | New |
| Headers | show |
| Series | igb: Add support for AF_XDP zero-copy | expand |
On Fri, Oct 18, 2024 at 10:40:02AM +0200, Kurt Kanzenbach wrote: > From: Sriram Yagnaraman <sriram.yagnaraman@est.tech> > > Add support for AF_XDP zero-copy transmit path. > > A new TX buffer type IGB_TYPE_XSK is introduced to indicate that the Tx > frame was allocated from the xsk buff pool, so igb_clean_tx_ring() and > igb_clean_tx_irq() can clean the buffers correctly based on type. > > igb_xmit_zc() performs the actual packet transmit when AF_XDP zero-copy is > enabled. We share the TX ring between slow path, XDP and AF_XDP > zero-copy, so we use the netdev queue lock to ensure mutual exclusion. > > Signed-off-by: Sriram Yagnaraman <sriram.yagnaraman@est.tech> > [Kurt: Set olinfo_status in igb_xmit_zc() so that frames are transmitted, > Use READ_ONCE() for xsk_pool and check Tx disabled and carrier in > igb_xmit_zc(), Add FIXME for RS bit] > Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de> > Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> I didn't give you my tag on this patch in previous revision, but from what I can see now it can stay here:) Finally, thanks! > --- > drivers/net/ethernet/intel/igb/igb.h | 2 + > drivers/net/ethernet/intel/igb/igb_main.c | 61 +++++++++++++++++++++++++----- > drivers/net/ethernet/intel/igb/igb_xsk.c | 63 +++++++++++++++++++++++++++++++ > 3 files changed, 116 insertions(+), 10 deletions(-) > > diff --git a/drivers/net/ethernet/intel/igb/igb.h b/drivers/net/ethernet/intel/igb/igb.h > index e4a85867aa18..02f340280d20 100644 > --- a/drivers/net/ethernet/intel/igb/igb.h > +++ b/drivers/net/ethernet/intel/igb/igb.h > @@ -258,6 +258,7 @@ enum igb_tx_flags { > enum igb_tx_buf_type { > IGB_TYPE_SKB = 0, > IGB_TYPE_XDP, > + IGB_TYPE_XSK > }; > > /* wrapper around a pointer to a socket buffer, > @@ -859,6 +860,7 @@ bool igb_alloc_rx_buffers_zc(struct igb_ring *rx_ring, > void igb_clean_rx_ring_zc(struct igb_ring *rx_ring); > int igb_clean_rx_irq_zc(struct igb_q_vector *q_vector, > struct xsk_buff_pool *xsk_pool, const int budget); > +bool igb_xmit_zc(struct igb_ring *tx_ring, struct xsk_buff_pool *xsk_pool); > int igb_xsk_wakeup(struct net_device *dev, u32 qid, u32 flags); > > #endif /* _IGB_H_ */ > diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c > index 711b60cab594..4587877d1761 100644 > --- a/drivers/net/ethernet/intel/igb/igb_main.c > +++ b/drivers/net/ethernet/intel/igb/igb_main.c > @@ -2979,6 +2979,9 @@ static int igb_xdp_xmit(struct net_device *dev, int n, > if (unlikely(!tx_ring)) > return -ENXIO; > > + if (unlikely(test_bit(IGB_RING_FLAG_TX_DISABLED, &tx_ring->flags))) > + return -ENXIO; > + > nq = txring_txq(tx_ring); > __netif_tx_lock(nq, cpu); > > @@ -3326,7 +3329,8 @@ static int igb_probe(struct pci_dev *pdev, const struct pci_device_id *ent) > netdev->priv_flags |= IFF_SUPP_NOFCS; > > netdev->priv_flags |= IFF_UNICAST_FLT; > - netdev->xdp_features = NETDEV_XDP_ACT_BASIC | NETDEV_XDP_ACT_REDIRECT; > + netdev->xdp_features = NETDEV_XDP_ACT_BASIC | NETDEV_XDP_ACT_REDIRECT | > + NETDEV_XDP_ACT_XSK_ZEROCOPY; > > /* MTU range: 68 - 9216 */ > netdev->min_mtu = ETH_MIN_MTU; > @@ -4900,15 +4904,20 @@ void igb_clean_tx_ring(struct igb_ring *tx_ring) > { > u16 i = tx_ring->next_to_clean; > struct igb_tx_buffer *tx_buffer = &tx_ring->tx_buffer_info[i]; > + u32 xsk_frames = 0; > > while (i != tx_ring->next_to_use) { > union e1000_adv_tx_desc *eop_desc, *tx_desc; > > /* Free all the Tx ring sk_buffs or xdp frames */ > - if (tx_buffer->type == IGB_TYPE_SKB) > + if (tx_buffer->type == IGB_TYPE_SKB) { > dev_kfree_skb_any(tx_buffer->skb); > - else > + } else if (tx_buffer->type == IGB_TYPE_XDP) { > xdp_return_frame(tx_buffer->xdpf); > + } else if (tx_buffer->type == IGB_TYPE_XSK) { > + xsk_frames++; > + goto skip_for_xsk; > + } > > /* unmap skb header data */ > dma_unmap_single(tx_ring->dev, > @@ -4939,6 +4948,7 @@ void igb_clean_tx_ring(struct igb_ring *tx_ring) > DMA_TO_DEVICE); > } > > +skip_for_xsk: > tx_buffer->next_to_watch = NULL; > > /* move us one more past the eop_desc for start of next pkt */ > @@ -4953,6 +4963,9 @@ void igb_clean_tx_ring(struct igb_ring *tx_ring) > /* reset BQL for queue */ > netdev_tx_reset_queue(txring_txq(tx_ring)); > > + if (tx_ring->xsk_pool && xsk_frames) > + xsk_tx_completed(tx_ring->xsk_pool, xsk_frames); > + > /* reset next_to_use and next_to_clean */ > tx_ring->next_to_use = 0; > tx_ring->next_to_clean = 0; > @@ -6486,6 +6499,9 @@ netdev_tx_t igb_xmit_frame_ring(struct sk_buff *skb, > return NETDEV_TX_BUSY; > } > > + if (unlikely(test_bit(IGB_RING_FLAG_TX_DISABLED, &tx_ring->flags))) > + return NETDEV_TX_BUSY; > + > /* record the location of the first descriptor for this packet */ > first = &tx_ring->tx_buffer_info[tx_ring->next_to_use]; > first->type = IGB_TYPE_SKB; > @@ -8260,13 +8276,18 @@ static int igb_poll(struct napi_struct *napi, int budget) > **/ > static bool igb_clean_tx_irq(struct igb_q_vector *q_vector, int napi_budget) > { > - struct igb_adapter *adapter = q_vector->adapter; > - struct igb_ring *tx_ring = q_vector->tx.ring; > - struct igb_tx_buffer *tx_buffer; > - union e1000_adv_tx_desc *tx_desc; > unsigned int total_bytes = 0, total_packets = 0; > + struct igb_adapter *adapter = q_vector->adapter; > unsigned int budget = q_vector->tx.work_limit; > + struct igb_ring *tx_ring = q_vector->tx.ring; > unsigned int i = tx_ring->next_to_clean; > + union e1000_adv_tx_desc *tx_desc; > + struct igb_tx_buffer *tx_buffer; > + struct xsk_buff_pool *xsk_pool; > + int cpu = smp_processor_id(); > + bool xsk_xmit_done = true; > + struct netdev_queue *nq; > + u32 xsk_frames = 0; > > if (test_bit(__IGB_DOWN, &adapter->state)) > return true; > @@ -8297,10 +8318,14 @@ static bool igb_clean_tx_irq(struct igb_q_vector *q_vector, int napi_budget) > total_packets += tx_buffer->gso_segs; > > /* free the skb */ > - if (tx_buffer->type == IGB_TYPE_SKB) > + if (tx_buffer->type == IGB_TYPE_SKB) { > napi_consume_skb(tx_buffer->skb, napi_budget); > - else > + } else if (tx_buffer->type == IGB_TYPE_XDP) { > xdp_return_frame(tx_buffer->xdpf); > + } else if (tx_buffer->type == IGB_TYPE_XSK) { > + xsk_frames++; > + goto skip_for_xsk; > + } > > /* unmap skb header data */ > dma_unmap_single(tx_ring->dev, > @@ -8332,6 +8357,7 @@ static bool igb_clean_tx_irq(struct igb_q_vector *q_vector, int napi_budget) > } > } > > +skip_for_xsk: > /* move us one more past the eop_desc for start of next pkt */ > tx_buffer++; > tx_desc++; > @@ -8360,6 +8386,21 @@ static bool igb_clean_tx_irq(struct igb_q_vector *q_vector, int napi_budget) > q_vector->tx.total_bytes += total_bytes; > q_vector->tx.total_packets += total_packets; > > + xsk_pool = READ_ONCE(tx_ring->xsk_pool); > + if (xsk_pool) { > + if (xsk_frames) > + xsk_tx_completed(xsk_pool, xsk_frames); > + if (xsk_uses_need_wakeup(xsk_pool)) > + xsk_set_tx_need_wakeup(xsk_pool); > + > + nq = txring_txq(tx_ring); > + __netif_tx_lock(nq, cpu); > + /* Avoid transmit queue timeout since we share it with the slow path */ > + txq_trans_cond_update(nq); > + xsk_xmit_done = igb_xmit_zc(tx_ring, xsk_pool); > + __netif_tx_unlock(nq); > + } > + > if (test_bit(IGB_RING_FLAG_TX_DETECT_HANG, &tx_ring->flags)) { > struct e1000_hw *hw = &adapter->hw; > > @@ -8422,7 +8463,7 @@ static bool igb_clean_tx_irq(struct igb_q_vector *q_vector, int napi_budget) > } > } > > - return !!budget; > + return !!budget && xsk_xmit_done; > } > > /** > diff --git a/drivers/net/ethernet/intel/igb/igb_xsk.c b/drivers/net/ethernet/intel/igb/igb_xsk.c > index 3d64a9f6360c..157d43787fa0 100644 > --- a/drivers/net/ethernet/intel/igb/igb_xsk.c > +++ b/drivers/net/ethernet/intel/igb/igb_xsk.c > @@ -461,6 +461,69 @@ int igb_clean_rx_irq_zc(struct igb_q_vector *q_vector, > return failure ? budget : (int)total_packets; > } > > +bool igb_xmit_zc(struct igb_ring *tx_ring, struct xsk_buff_pool *xsk_pool) > +{ > + unsigned int budget = igb_desc_unused(tx_ring); > + u32 cmd_type, olinfo_status, nb_pkts, i = 0; > + struct xdp_desc *descs = xsk_pool->tx_descs; > + union e1000_adv_tx_desc *tx_desc = NULL; > + struct igb_tx_buffer *tx_buffer_info; > + unsigned int total_bytes = 0; > + dma_addr_t dma; > + > + if (!netif_carrier_ok(tx_ring->netdev)) > + return true; > + > + if (test_bit(IGB_RING_FLAG_TX_DISABLED, &tx_ring->flags)) > + return true; > + > + nb_pkts = xsk_tx_peek_release_desc_batch(xsk_pool, budget); > + if (!nb_pkts) > + return true; > + > + while (nb_pkts-- > 0) { > + dma = xsk_buff_raw_get_dma(xsk_pool, descs[i].addr); > + xsk_buff_raw_dma_sync_for_device(xsk_pool, dma, descs[i].len); > + > + tx_buffer_info = &tx_ring->tx_buffer_info[tx_ring->next_to_use]; > + tx_buffer_info->bytecount = descs[i].len; > + tx_buffer_info->type = IGB_TYPE_XSK; > + tx_buffer_info->xdpf = NULL; > + tx_buffer_info->gso_segs = 1; > + tx_buffer_info->time_stamp = jiffies; > + > + tx_desc = IGB_TX_DESC(tx_ring, tx_ring->next_to_use); > + tx_desc->read.buffer_addr = cpu_to_le64(dma); > + > + /* put descriptor type bits */ > + cmd_type = E1000_ADVTXD_DTYP_DATA | E1000_ADVTXD_DCMD_DEXT | > + E1000_ADVTXD_DCMD_IFCS; > + olinfo_status = descs[i].len << E1000_ADVTXD_PAYLEN_SHIFT; > + > + /* FIXME: This sets the Report Status (RS) bit for every > + * descriptor. One nice to have optimization would be to set it > + * only for the last descriptor in the whole batch. See Intel > + * ice driver for an example on how to do it. > + */ > + cmd_type |= descs[i].len | IGB_TXD_DCMD; > + tx_desc->read.cmd_type_len = cpu_to_le32(cmd_type); > + tx_desc->read.olinfo_status = cpu_to_le32(olinfo_status); > + > + total_bytes += descs[i].len; > + > + i++; > + tx_ring->next_to_use++; > + tx_buffer_info->next_to_watch = tx_desc; > + if (tx_ring->next_to_use == tx_ring->count) > + tx_ring->next_to_use = 0; > + } > + > + netdev_tx_sent_queue(txring_txq(tx_ring), total_bytes); > + igb_xdp_ring_update_tail(tx_ring); > + > + return nb_pkts < budget; > +} > + > int igb_xsk_wakeup(struct net_device *dev, u32 qid, u32 flags) > { > struct igb_adapter *adapter = netdev_priv(dev); > > -- > 2.39.5 >
diff --git a/drivers/net/ethernet/intel/igb/igb.h b/drivers/net/ethernet/intel/igb/igb.h index e4a85867aa18..02f340280d20 100644 --- a/drivers/net/ethernet/intel/igb/igb.h +++ b/drivers/net/ethernet/intel/igb/igb.h @@ -258,6 +258,7 @@ enum igb_tx_flags { enum igb_tx_buf_type { IGB_TYPE_SKB = 0, IGB_TYPE_XDP, + IGB_TYPE_XSK }; /* wrapper around a pointer to a socket buffer, @@ -859,6 +860,7 @@ bool igb_alloc_rx_buffers_zc(struct igb_ring *rx_ring, void igb_clean_rx_ring_zc(struct igb_ring *rx_ring); int igb_clean_rx_irq_zc(struct igb_q_vector *q_vector, struct xsk_buff_pool *xsk_pool, const int budget); +bool igb_xmit_zc(struct igb_ring *tx_ring, struct xsk_buff_pool *xsk_pool); int igb_xsk_wakeup(struct net_device *dev, u32 qid, u32 flags); #endif /* _IGB_H_ */ diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c index 711b60cab594..4587877d1761 100644 --- a/drivers/net/ethernet/intel/igb/igb_main.c +++ b/drivers/net/ethernet/intel/igb/igb_main.c @@ -2979,6 +2979,9 @@ static int igb_xdp_xmit(struct net_device *dev, int n, if (unlikely(!tx_ring)) return -ENXIO; + if (unlikely(test_bit(IGB_RING_FLAG_TX_DISABLED, &tx_ring->flags))) + return -ENXIO; + nq = txring_txq(tx_ring); __netif_tx_lock(nq, cpu); @@ -3326,7 +3329,8 @@ static int igb_probe(struct pci_dev *pdev, const struct pci_device_id *ent) netdev->priv_flags |= IFF_SUPP_NOFCS; netdev->priv_flags |= IFF_UNICAST_FLT; - netdev->xdp_features = NETDEV_XDP_ACT_BASIC | NETDEV_XDP_ACT_REDIRECT; + netdev->xdp_features = NETDEV_XDP_ACT_BASIC | NETDEV_XDP_ACT_REDIRECT | + NETDEV_XDP_ACT_XSK_ZEROCOPY; /* MTU range: 68 - 9216 */ netdev->min_mtu = ETH_MIN_MTU; @@ -4900,15 +4904,20 @@ void igb_clean_tx_ring(struct igb_ring *tx_ring) { u16 i = tx_ring->next_to_clean; struct igb_tx_buffer *tx_buffer = &tx_ring->tx_buffer_info[i]; + u32 xsk_frames = 0; while (i != tx_ring->next_to_use) { union e1000_adv_tx_desc *eop_desc, *tx_desc; /* Free all the Tx ring sk_buffs or xdp frames */ - if (tx_buffer->type == IGB_TYPE_SKB) + if (tx_buffer->type == IGB_TYPE_SKB) { dev_kfree_skb_any(tx_buffer->skb); - else + } else if (tx_buffer->type == IGB_TYPE_XDP) { xdp_return_frame(tx_buffer->xdpf); + } else if (tx_buffer->type == IGB_TYPE_XSK) { + xsk_frames++; + goto skip_for_xsk; + } /* unmap skb header data */ dma_unmap_single(tx_ring->dev, @@ -4939,6 +4948,7 @@ void igb_clean_tx_ring(struct igb_ring *tx_ring) DMA_TO_DEVICE); } +skip_for_xsk: tx_buffer->next_to_watch = NULL; /* move us one more past the eop_desc for start of next pkt */ @@ -4953,6 +4963,9 @@ void igb_clean_tx_ring(struct igb_ring *tx_ring) /* reset BQL for queue */ netdev_tx_reset_queue(txring_txq(tx_ring)); + if (tx_ring->xsk_pool && xsk_frames) + xsk_tx_completed(tx_ring->xsk_pool, xsk_frames); + /* reset next_to_use and next_to_clean */ tx_ring->next_to_use = 0; tx_ring->next_to_clean = 0; @@ -6486,6 +6499,9 @@ netdev_tx_t igb_xmit_frame_ring(struct sk_buff *skb, return NETDEV_TX_BUSY; } + if (unlikely(test_bit(IGB_RING_FLAG_TX_DISABLED, &tx_ring->flags))) + return NETDEV_TX_BUSY; + /* record the location of the first descriptor for this packet */ first = &tx_ring->tx_buffer_info[tx_ring->next_to_use]; first->type = IGB_TYPE_SKB; @@ -8260,13 +8276,18 @@ static int igb_poll(struct napi_struct *napi, int budget) **/ static bool igb_clean_tx_irq(struct igb_q_vector *q_vector, int napi_budget) { - struct igb_adapter *adapter = q_vector->adapter; - struct igb_ring *tx_ring = q_vector->tx.ring; - struct igb_tx_buffer *tx_buffer; - union e1000_adv_tx_desc *tx_desc; unsigned int total_bytes = 0, total_packets = 0; + struct igb_adapter *adapter = q_vector->adapter; unsigned int budget = q_vector->tx.work_limit; + struct igb_ring *tx_ring = q_vector->tx.ring; unsigned int i = tx_ring->next_to_clean; + union e1000_adv_tx_desc *tx_desc; + struct igb_tx_buffer *tx_buffer; + struct xsk_buff_pool *xsk_pool; + int cpu = smp_processor_id(); + bool xsk_xmit_done = true; + struct netdev_queue *nq; + u32 xsk_frames = 0; if (test_bit(__IGB_DOWN, &adapter->state)) return true; @@ -8297,10 +8318,14 @@ static bool igb_clean_tx_irq(struct igb_q_vector *q_vector, int napi_budget) total_packets += tx_buffer->gso_segs; /* free the skb */ - if (tx_buffer->type == IGB_TYPE_SKB) + if (tx_buffer->type == IGB_TYPE_SKB) { napi_consume_skb(tx_buffer->skb, napi_budget); - else + } else if (tx_buffer->type == IGB_TYPE_XDP) { xdp_return_frame(tx_buffer->xdpf); + } else if (tx_buffer->type == IGB_TYPE_XSK) { + xsk_frames++; + goto skip_for_xsk; + } /* unmap skb header data */ dma_unmap_single(tx_ring->dev, @@ -8332,6 +8357,7 @@ static bool igb_clean_tx_irq(struct igb_q_vector *q_vector, int napi_budget) } } +skip_for_xsk: /* move us one more past the eop_desc for start of next pkt */ tx_buffer++; tx_desc++; @@ -8360,6 +8386,21 @@ static bool igb_clean_tx_irq(struct igb_q_vector *q_vector, int napi_budget) q_vector->tx.total_bytes += total_bytes; q_vector->tx.total_packets += total_packets; + xsk_pool = READ_ONCE(tx_ring->xsk_pool); + if (xsk_pool) { + if (xsk_frames) + xsk_tx_completed(xsk_pool, xsk_frames); + if (xsk_uses_need_wakeup(xsk_pool)) + xsk_set_tx_need_wakeup(xsk_pool); + + nq = txring_txq(tx_ring); + __netif_tx_lock(nq, cpu); + /* Avoid transmit queue timeout since we share it with the slow path */ + txq_trans_cond_update(nq); + xsk_xmit_done = igb_xmit_zc(tx_ring, xsk_pool); + __netif_tx_unlock(nq); + } + if (test_bit(IGB_RING_FLAG_TX_DETECT_HANG, &tx_ring->flags)) { struct e1000_hw *hw = &adapter->hw; @@ -8422,7 +8463,7 @@ static bool igb_clean_tx_irq(struct igb_q_vector *q_vector, int napi_budget) } } - return !!budget; + return !!budget && xsk_xmit_done; } /** diff --git a/drivers/net/ethernet/intel/igb/igb_xsk.c b/drivers/net/ethernet/intel/igb/igb_xsk.c index 3d64a9f6360c..157d43787fa0 100644 --- a/drivers/net/ethernet/intel/igb/igb_xsk.c +++ b/drivers/net/ethernet/intel/igb/igb_xsk.c @@ -461,6 +461,69 @@ int igb_clean_rx_irq_zc(struct igb_q_vector *q_vector, return failure ? budget : (int)total_packets; } +bool igb_xmit_zc(struct igb_ring *tx_ring, struct xsk_buff_pool *xsk_pool) +{ + unsigned int budget = igb_desc_unused(tx_ring); + u32 cmd_type, olinfo_status, nb_pkts, i = 0; + struct xdp_desc *descs = xsk_pool->tx_descs; + union e1000_adv_tx_desc *tx_desc = NULL; + struct igb_tx_buffer *tx_buffer_info; + unsigned int total_bytes = 0; + dma_addr_t dma; + + if (!netif_carrier_ok(tx_ring->netdev)) + return true; + + if (test_bit(IGB_RING_FLAG_TX_DISABLED, &tx_ring->flags)) + return true; + + nb_pkts = xsk_tx_peek_release_desc_batch(xsk_pool, budget); + if (!nb_pkts) + return true; + + while (nb_pkts-- > 0) { + dma = xsk_buff_raw_get_dma(xsk_pool, descs[i].addr); + xsk_buff_raw_dma_sync_for_device(xsk_pool, dma, descs[i].len); + + tx_buffer_info = &tx_ring->tx_buffer_info[tx_ring->next_to_use]; + tx_buffer_info->bytecount = descs[i].len; + tx_buffer_info->type = IGB_TYPE_XSK; + tx_buffer_info->xdpf = NULL; + tx_buffer_info->gso_segs = 1; + tx_buffer_info->time_stamp = jiffies; + + tx_desc = IGB_TX_DESC(tx_ring, tx_ring->next_to_use); + tx_desc->read.buffer_addr = cpu_to_le64(dma); + + /* put descriptor type bits */ + cmd_type = E1000_ADVTXD_DTYP_DATA | E1000_ADVTXD_DCMD_DEXT | + E1000_ADVTXD_DCMD_IFCS; + olinfo_status = descs[i].len << E1000_ADVTXD_PAYLEN_SHIFT; + + /* FIXME: This sets the Report Status (RS) bit for every + * descriptor. One nice to have optimization would be to set it + * only for the last descriptor in the whole batch. See Intel + * ice driver for an example on how to do it. + */ + cmd_type |= descs[i].len | IGB_TXD_DCMD; + tx_desc->read.cmd_type_len = cpu_to_le32(cmd_type); + tx_desc->read.olinfo_status = cpu_to_le32(olinfo_status); + + total_bytes += descs[i].len; + + i++; + tx_ring->next_to_use++; + tx_buffer_info->next_to_watch = tx_desc; + if (tx_ring->next_to_use == tx_ring->count) + tx_ring->next_to_use = 0; + } + + netdev_tx_sent_queue(txring_txq(tx_ring), total_bytes); + igb_xdp_ring_update_tail(tx_ring); + + return nb_pkts < budget; +} + int igb_xsk_wakeup(struct net_device *dev, u32 qid, u32 flags) { struct igb_adapter *adapter = netdev_priv(dev);