From: Uwe Kleine-König <u.kleine-koe...@pengutronix.de> Sent: Tuesday, May 03,
2016 10:39 PM
> To: Fugang Duan <fugang.d...@nxp.com>; David S . Miller
> <da...@davemloft.net>
> Cc: ker...@pengutronix.de; netdev@vger.kernel.org
> Subject: [PATCH] net: fec: only clear a queue's work bit if the queue was
> emptied
>
> In the receive path a queue's work bit was cleared unconditionally even if
> fec_enet_rx_queue only read out a part of the available packets from the
> hardware. This resulted in not reading any packets in the next napi turn and
> so
> packets were delayed or lost.
>
> The obvious fix is to only clear a queue's bit when the queue was emptied.
>
> Fixes: 4d494cdc92b3 ("net: fec: change data structure to support multiqueue")
> Signed-off-by: Uwe Kleine-König <u.kleine-koe...@pengutronix.de>
> ---
> Hello,
>
> I created this patch against net/master. If you think it's to late to get it
> into 4.6
> and it doesn't fit on net-next/master, just tell me and I will rebase.
>
> Best regards
> Uwe
>
>
> drivers/net/ethernet/freescale/fec_main.c | 10 ++++++++--
> 1 file changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/ethernet/freescale/fec_main.c
> b/drivers/net/ethernet/freescale/fec_main.c
> index 08243c2ff4b4..2a03857cca18 100644
> --- a/drivers/net/ethernet/freescale/fec_main.c
> +++ b/drivers/net/ethernet/freescale/fec_main.c
> @@ -1521,9 +1521,15 @@ fec_enet_rx(struct net_device *ndev, int budget)
> struct fec_enet_private *fep = netdev_priv(ndev);
>
> for_each_set_bit(queue_id, &fep->work_rx, FEC_ENET_MAX_RX_QS) {
> - clear_bit(queue_id, &fep->work_rx);
> - pkt_received += fec_enet_rx_queue(ndev,
> + int ret;
> +
> + ret = fec_enet_rx_queue(ndev,
> budget - pkt_received, queue_id);
> +
> + if (ret < budget - pkt_received)
> + clear_bit(queue_id, &fep->work_rx);
> +
> + pkt_received += ret;
> }
> return pkt_received;
> }
> --
> 2.8.0.rc3
Tested-by: Fugang Duan <fugang.d...@nxp.com>
Acked-by: Fugang Duan <fugang.d...@nxp.com>
