From: Sriram Yagnaraman <sriram.yagnaraman@xxxxxxxx> 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@xxxxxxxx> [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()] Signed-off-by: Kurt Kanzenbach <kurt@xxxxxxxxxxxxx> Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@xxxxxxxxx> --- 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 | 59 ++++++++++++++++++++++++++++++ 3 files changed, 112 insertions(+), 10 deletions(-) diff --git a/drivers/net/ethernet/intel/igb/igb.h b/drivers/net/ethernet/intel/igb/igb.h index ea3977b313fc..d65bf0dc634f 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, @@ -858,6 +859,7 @@ bool igb_alloc_rx_buffers_zc(struct igb_ring *rx_ring, u16 count); 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); 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 449ee794b3c9..7a07071d9d16 100644 --- a/drivers/net/ethernet/intel/igb/igb_main.c +++ b/drivers/net/ethernet/intel/igb/igb_main.c @@ -2978,6 +2978,9 @@ 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); @@ -3325,7 +3328,8 @@ 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; @@ -4899,15 +4903,20 @@ 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, @@ -4938,6 +4947,7 @@ 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 */ @@ -4952,6 +4962,9 @@ 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; @@ -6485,6 +6498,9 @@ 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; @@ -8259,13 +8275,18 @@ 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; @@ -8296,10 +8317,14 @@ 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, @@ -8331,6 +8356,7 @@ 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++; @@ -8359,6 +8385,21 @@ 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); + __netif_tx_unlock(nq); + } + if (test_bit(IGB_RING_FLAG_TX_DETECT_HANG, &tx_ring->flags)) { struct e1000_hw *hw = &adapter->hw; @@ -8421,7 +8462,7 @@ 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 9fd094a799fa..6c56af9548e1 100644 --- a/drivers/net/ethernet/intel/igb/igb_xsk.c +++ b/drivers/net/ethernet/intel/igb/igb_xsk.c @@ -463,6 +463,65 @@ 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) +{ + unsigned int budget = igb_desc_unused(tx_ring); + struct xsk_buff_pool *pool = tx_ring->xsk_pool; + u32 cmd_type, olinfo_status, nb_pkts, i = 0; + struct xdp_desc *descs = 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(pool, budget); + if (!nb_pkts) + return true; + + while (nb_pkts-- > 0) { + dma = xsk_buff_raw_get_dma(pool, descs[i].addr); + xsk_buff_raw_dma_sync_for_device(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; + + 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