From af6f4791380c320802df2106e295efd29c5e8b16 Mon Sep 17 00:00:00 2001 From: Wei Fang Date: Tue, 15 Aug 2023 13:19:55 +0800 Subject: net: fec: improve XDP_TX performance As suggested by Jesper and Alexander, we can avoid converting xdp_buff to xdp_frame in case of XDP_TX to save a bunch of CPU cycles, so that we can further improve the XDP_TX performance. Before this patch on i.MX8MP-EVK board, the performance shows as follows. root@imx8mpevk:~# ./xdp2 eth0 proto 17: 353918 pkt/s proto 17: 352923 pkt/s proto 17: 353900 pkt/s proto 17: 352672 pkt/s proto 17: 353912 pkt/s proto 17: 354219 pkt/s After applying this patch, the performance is improved. root@imx8mpevk:~# ./xdp2 eth0 proto 17: 369261 pkt/s proto 17: 369267 pkt/s proto 17: 369206 pkt/s proto 17: 369214 pkt/s proto 17: 369126 pkt/s proto 17: 369272 pkt/s Signed-off-by: Wei Fang Suggested-by: Alexander Lobakin Suggested-by: Jesper Dangaard Brouer Reviewed-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller --- drivers/net/ethernet/freescale/fec.h | 5 +- drivers/net/ethernet/freescale/fec_main.c | 140 ++++++++++++++++-------------- 2 files changed, 75 insertions(+), 70 deletions(-) diff --git a/drivers/net/ethernet/freescale/fec.h b/drivers/net/ethernet/freescale/fec.h index 7bb02a9da2a6..a8fbcada6b01 100644 --- a/drivers/net/ethernet/freescale/fec.h +++ b/drivers/net/ethernet/freescale/fec.h @@ -552,10 +552,7 @@ enum fec_txbuf_type { }; struct fec_tx_buffer { - union { - struct sk_buff *skb; - struct xdp_frame *xdp; - }; + void *buf_p; enum fec_txbuf_type type; }; diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c index 9bba3d7c949c..f77105f017c1 100644 --- a/drivers/net/ethernet/freescale/fec_main.c +++ b/drivers/net/ethernet/freescale/fec_main.c @@ -400,7 +400,7 @@ static void fec_dump(struct net_device *ndev) fec16_to_cpu(bdp->cbd_sc), fec32_to_cpu(bdp->cbd_bufaddr), fec16_to_cpu(bdp->cbd_datlen), - txq->tx_buf[index].skb); + txq->tx_buf[index].buf_p); bdp = fec_enet_get_nextdesc(bdp, &txq->bd); index++; } while (bdp != txq->bd.base); @@ -657,7 +657,7 @@ static int fec_enet_txq_submit_skb(struct fec_enet_priv_tx_q *txq, index = fec_enet_get_bd_index(last_bdp, &txq->bd); /* Save skb pointer */ - txq->tx_buf[index].skb = skb; + txq->tx_buf[index].buf_p = skb; /* Make sure the updates to rest of the descriptor are performed before * transferring ownership. @@ -863,7 +863,7 @@ static int fec_enet_txq_submit_tso(struct fec_enet_priv_tx_q *txq, } /* Save skb pointer */ - txq->tx_buf[index].skb = skb; + txq->tx_buf[index].buf_p = skb; skb_tx_timestamp(skb); txq->bd.cur = bdp; @@ -960,27 +960,27 @@ static void fec_enet_bd_init(struct net_device *dev) fec32_to_cpu(bdp->cbd_bufaddr), fec16_to_cpu(bdp->cbd_datlen), DMA_TO_DEVICE); - if (txq->tx_buf[i].skb) { - dev_kfree_skb_any(txq->tx_buf[i].skb); - txq->tx_buf[i].skb = NULL; - } - } else { - if (bdp->cbd_bufaddr && - txq->tx_buf[i].type == FEC_TXBUF_T_XDP_NDO) + if (txq->tx_buf[i].buf_p) + dev_kfree_skb_any(txq->tx_buf[i].buf_p); + } else if (txq->tx_buf[i].type == FEC_TXBUF_T_XDP_NDO) { + if (bdp->cbd_bufaddr) dma_unmap_single(&fep->pdev->dev, fec32_to_cpu(bdp->cbd_bufaddr), fec16_to_cpu(bdp->cbd_datlen), DMA_TO_DEVICE); - if (txq->tx_buf[i].xdp) { - xdp_return_frame(txq->tx_buf[i].xdp); - txq->tx_buf[i].xdp = NULL; - } + if (txq->tx_buf[i].buf_p) + xdp_return_frame(txq->tx_buf[i].buf_p); + } else { + struct page *page = txq->tx_buf[i].buf_p; - /* restore default tx buffer type: FEC_TXBUF_T_SKB */ - txq->tx_buf[i].type = FEC_TXBUF_T_SKB; + if (page) + page_pool_put_page(page->pp, page, 0, false); } + txq->tx_buf[i].buf_p = NULL; + /* restore default tx buffer type: FEC_TXBUF_T_SKB */ + txq->tx_buf[i].type = FEC_TXBUF_T_SKB; bdp->cbd_bufaddr = cpu_to_fec32(0); bdp = fec_enet_get_nextdesc(bdp, &txq->bd); } @@ -1387,6 +1387,8 @@ fec_enet_tx_queue(struct net_device *ndev, u16 queue_id, int budget) struct netdev_queue *nq; int index = 0; int entries_free; + struct page *page; + int frame_len; fep = netdev_priv(ndev); @@ -1408,8 +1410,7 @@ fec_enet_tx_queue(struct net_device *ndev, u16 queue_id, int budget) index = fec_enet_get_bd_index(bdp, &txq->bd); if (txq->tx_buf[index].type == FEC_TXBUF_T_SKB) { - skb = txq->tx_buf[index].skb; - txq->tx_buf[index].skb = NULL; + skb = txq->tx_buf[index].buf_p; if (bdp->cbd_bufaddr && !IS_TSO_HEADER(txq, fec32_to_cpu(bdp->cbd_bufaddr))) dma_unmap_single(&fep->pdev->dev, @@ -1428,18 +1429,24 @@ fec_enet_tx_queue(struct net_device *ndev, u16 queue_id, int budget) if (unlikely(!budget)) break; - xdpf = txq->tx_buf[index].xdp; - if (bdp->cbd_bufaddr && - txq->tx_buf[index].type == FEC_TXBUF_T_XDP_NDO) - dma_unmap_single(&fep->pdev->dev, - fec32_to_cpu(bdp->cbd_bufaddr), - fec16_to_cpu(bdp->cbd_datlen), - DMA_TO_DEVICE); + if (txq->tx_buf[index].type == FEC_TXBUF_T_XDP_NDO) { + xdpf = txq->tx_buf[index].buf_p; + if (bdp->cbd_bufaddr) + dma_unmap_single(&fep->pdev->dev, + fec32_to_cpu(bdp->cbd_bufaddr), + fec16_to_cpu(bdp->cbd_datlen), + DMA_TO_DEVICE); + } else { + page = txq->tx_buf[index].buf_p; + } + bdp->cbd_bufaddr = cpu_to_fec32(0); - if (unlikely(!xdpf)) { + if (unlikely(!txq->tx_buf[index].buf_p)) { txq->tx_buf[index].type = FEC_TXBUF_T_SKB; goto tx_buf_done; } + + frame_len = fec16_to_cpu(bdp->cbd_datlen); } /* Check for errors. */ @@ -1463,7 +1470,7 @@ fec_enet_tx_queue(struct net_device *ndev, u16 queue_id, int budget) if (txq->tx_buf[index].type == FEC_TXBUF_T_SKB) ndev->stats.tx_bytes += skb->len; else - ndev->stats.tx_bytes += xdpf->len; + ndev->stats.tx_bytes += frame_len; } /* Deferred means some collisions occurred during transmit, @@ -1488,23 +1495,17 @@ fec_enet_tx_queue(struct net_device *ndev, u16 queue_id, int budget) /* Free the sk buffer associated with this last transmit */ dev_kfree_skb_any(skb); - } else { - if (txq->tx_buf[index].type == FEC_TXBUF_T_XDP_NDO) { - xdp_return_frame_rx_napi(xdpf); - } else { /* recycle pages of XDP_TX frames */ - struct page *page = virt_to_head_page(xdpf->data); - - /* The dma_sync_size = 0 as XDP_TX has already - * synced DMA for_device. - */ - page_pool_put_page(page->pp, page, 0, true); - } - - txq->tx_buf[index].xdp = NULL; - /* restore default tx buffer type: FEC_TXBUF_T_SKB */ - txq->tx_buf[index].type = FEC_TXBUF_T_SKB; + } else if (txq->tx_buf[index].type == FEC_TXBUF_T_XDP_NDO) { + xdp_return_frame_rx_napi(xdpf); + } else { /* recycle pages of XDP_TX frames */ + /* The dma_sync_size = 0 as XDP_TX has already synced DMA for_device */ + page_pool_put_page(page->pp, page, 0, true); } + txq->tx_buf[index].buf_p = NULL; + /* restore default tx buffer type: FEC_TXBUF_T_SKB */ + txq->tx_buf[index].type = FEC_TXBUF_T_SKB; + tx_buf_done: /* Make sure the update to bdp and tx_buf are performed * before dirty_tx @@ -3234,7 +3235,6 @@ static void fec_enet_free_buffers(struct net_device *ndev) { struct fec_enet_private *fep = netdev_priv(ndev); unsigned int i; - struct sk_buff *skb; struct fec_enet_priv_tx_q *txq; struct fec_enet_priv_rx_q *rxq; unsigned int q; @@ -3259,18 +3259,23 @@ static void fec_enet_free_buffers(struct net_device *ndev) kfree(txq->tx_bounce[i]); txq->tx_bounce[i] = NULL; + if (!txq->tx_buf[i].buf_p) { + txq->tx_buf[i].type = FEC_TXBUF_T_SKB; + continue; + } + if (txq->tx_buf[i].type == FEC_TXBUF_T_SKB) { - skb = txq->tx_buf[i].skb; - txq->tx_buf[i].skb = NULL; - dev_kfree_skb(skb); + dev_kfree_skb(txq->tx_buf[i].buf_p); + } else if (txq->tx_buf[i].type == FEC_TXBUF_T_XDP_NDO) { + xdp_return_frame(txq->tx_buf[i].buf_p); } else { - if (txq->tx_buf[i].xdp) { - xdp_return_frame(txq->tx_buf[i].xdp); - txq->tx_buf[i].xdp = NULL; - } + struct page *page = txq->tx_buf[i].buf_p; - txq->tx_buf[i].type = FEC_TXBUF_T_SKB; + page_pool_put_page(page->pp, page, 0, false); } + + txq->tx_buf[i].buf_p = NULL; + txq->tx_buf[i].type = FEC_TXBUF_T_SKB; } } } @@ -3793,13 +3798,14 @@ fec_enet_xdp_get_tx_queue(struct fec_enet_private *fep, int index) static int fec_enet_txq_xmit_frame(struct fec_enet_private *fep, struct fec_enet_priv_tx_q *txq, - struct xdp_frame *frame, - u32 dma_sync_len, bool ndo_xmit) + void *frame, u32 dma_sync_len, + bool ndo_xmit) { unsigned int index, status, estatus; struct bufdesc *bdp; dma_addr_t dma_addr; int entries_free; + u16 frame_len; entries_free = fec_enet_get_free_txdesc_num(txq); if (entries_free < MAX_SKB_FRAGS + 1) { @@ -3815,30 +3821,36 @@ static int fec_enet_txq_xmit_frame(struct fec_enet_private *fep, index = fec_enet_get_bd_index(bdp, &txq->bd); if (ndo_xmit) { - dma_addr = dma_map_single(&fep->pdev->dev, frame->data, - frame->len, DMA_TO_DEVICE); + struct xdp_frame *xdpf = frame; + + dma_addr = dma_map_single(&fep->pdev->dev, xdpf->data, + xdpf->len, DMA_TO_DEVICE); if (dma_mapping_error(&fep->pdev->dev, dma_addr)) return -ENOMEM; + frame_len = xdpf->len; + txq->tx_buf[index].buf_p = xdpf; txq->tx_buf[index].type = FEC_TXBUF_T_XDP_NDO; } else { - struct page *page = virt_to_page(frame->data); + struct xdp_buff *xdpb = frame; + struct page *page; - dma_addr = page_pool_get_dma_addr(page) + sizeof(*frame) + - frame->headroom; + page = virt_to_page(xdpb->data); + dma_addr = page_pool_get_dma_addr(page) + + (xdpb->data - xdpb->data_hard_start); dma_sync_single_for_device(&fep->pdev->dev, dma_addr, dma_sync_len, DMA_BIDIRECTIONAL); + frame_len = xdpb->data_end - xdpb->data; + txq->tx_buf[index].buf_p = page; txq->tx_buf[index].type = FEC_TXBUF_T_XDP_TX; } - txq->tx_buf[index].xdp = frame; - status |= (BD_ENET_TX_INTR | BD_ENET_TX_LAST); if (fep->bufdesc_ex) estatus = BD_ENET_TX_INT; bdp->cbd_bufaddr = cpu_to_fec32(dma_addr); - bdp->cbd_datlen = cpu_to_fec16(frame->len); + bdp->cbd_datlen = cpu_to_fec16(frame_len); if (fep->bufdesc_ex) { struct bufdesc_ex *ebdp = (struct bufdesc_ex *)bdp; @@ -3879,14 +3891,10 @@ static int fec_enet_xdp_tx_xmit(struct fec_enet_private *fep, int cpu, struct xdp_buff *xdp, u32 dma_sync_len) { - struct xdp_frame *xdpf = xdp_convert_buff_to_frame(xdp); struct fec_enet_priv_tx_q *txq; struct netdev_queue *nq; int queue, ret; - if (unlikely(!xdpf)) - return -EFAULT; - queue = fec_enet_xdp_get_tx_queue(fep, cpu); txq = fep->tx_queue[queue]; nq = netdev_get_tx_queue(fep->netdev, queue); @@ -3895,7 +3903,7 @@ static int fec_enet_xdp_tx_xmit(struct fec_enet_private *fep, /* Avoid tx timeout as XDP shares the queue with kernel stack */ txq_trans_cond_update(nq); - ret = fec_enet_txq_xmit_frame(fep, txq, xdpf, dma_sync_len, false); + ret = fec_enet_txq_xmit_frame(fep, txq, xdp, dma_sync_len, false); __netif_tx_unlock(nq); -- cgit