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Frequent MMIO writes consume more CPU cycles > and may reduce XDP TX performance, so transmit XDP frames in bulk. > > Signed-off-by: Wei Fang > --- Did you test light loading case? Any unexpected latency happen? sometime missing trigger is hard to find when heavy loading. Frank > 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 0b114a68cd8e..f3e93598a27c 100644 > --- a/drivers/net/ethernet/freescale/fec_main.c > +++ b/drivers/net/ethernet/freescale/fec_main.c > @@ -1994,6 +1994,8 @@ 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: > @@ -2043,6 +2045,10 @@ 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[queue]); > + > return pkt_received; > } > > @@ -4033,9 +4039,6 @@ 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; > } > > @@ -4087,6 +4090,9 @@ 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 >