[PATCH v2 net-next 07/14] net: fec: transmit XDP frames in bulk
From: Wei Fang <wei.fang@nxp.com>
Date: 2026-01-16 07:41:46
Also in:
bpf, imx, lkml
Subsystem:
freescale imx / mxc fec driver, networking drivers, the rest · Maintainers:
Wei Fang, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Currently, the driver writes the ENET_TDAR register for every XDP frame to trigger transmit start. Frequent MMIO writes consume more CPU cycles and may reduce XDP TX performance, so transmit XDP frames in bulk. Signed-off-by: Wei Fang <wei.fang@nxp.com> --- drivers/net/ethernet/freescale/fec_main.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index 251191ab99b3..52abeeb50dda 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c@@ -2006,6 +2006,8 @@ static int fec_enet_rx_queue_xdp(struct fec_enet_private *fep, int queue, rxq->stats[RX_XDP_TX_ERRORS]++; fec_xdp_drop(rxq, &xdp, sync); trace_xdp_exception(ndev, prog, XDP_TX); + } else { + xdp_res |= FEC_ENET_XDP_TX; } break; default:
@@ -2055,6 +2057,10 @@ static int fec_enet_rx_queue_xdp(struct fec_enet_private *fep, int queue, if (xdp_res & FEC_ENET_XDP_REDIR) xdp_do_flush(); + if (xdp_res & FEC_ENET_XDP_TX) + /* Trigger transmission start */ + fec_txq_trigger_xmit(fep, fep->tx_queue[tx_qid]); + return pkt_received; }
@@ -4036,9 +4042,6 @@ static int fec_enet_txq_xmit_frame(struct fec_enet_private *fep, txq->bd.cur = bdp; - /* Trigger transmission start */ - fec_txq_trigger_xmit(fep, txq); - return 0; }
@@ -4088,6 +4091,9 @@ static int fec_enet_xdp_xmit(struct net_device *dev, sent_frames++; } + if (sent_frames) + fec_txq_trigger_xmit(fep, txq); + __netif_tx_unlock(nq); return sent_frames;
--
2.34.1