target/linux/mvebu/patches-5.4/700-mvneta-tx-queue-workaround.patch

   1 The hardware queue scheduling is apparently configured with fixed
   2 priorities, which creates a nasty fairness issue where traffic from one
   3 CPU can starve traffic from all other CPUs.
   4
   5 Work around this issue by forcing all tx packets to go through one CPU,
   6 until this issue is fixed properly.
   7
   8 Signed-off-by: Felix Fietkau <nbd@nbd.name>
   9 ---
  10 --- a/drivers/net/ethernet/marvell/mvneta.c
  11 +++ b/drivers/net/ethernet/marvell/mvneta.c
  12 @@ -4684,6 +4684,14 @@ static int mvneta_ethtool_set_eee(struct
  13         return phylink_ethtool_set_eee(pp->phylink, eee);
  14  }
  15
  16 +static u16 mvneta_select_queue(struct net_device *dev, struct sk_buff *skb,
  17 +                              struct net_device *sb_dev)
  18 +{
  19 +       /* XXX: hardware queue scheduling is broken,
  20 +        * use only one queue until it is fixed */
  21 +       return 0;
  22 +}
  23 +
  24  static const struct net_device_ops mvneta_netdev_ops = {
  25         .ndo_open            = mvneta_open,
  26         .ndo_stop            = mvneta_stop,
  27 @@ -4694,6 +4702,7 @@ static const struct net_device_ops mvnet
  28         .ndo_fix_features    = mvneta_fix_features,
  29         .ndo_get_stats64     = mvneta_get_stats64,
  30         .ndo_do_ioctl        = mvneta_ioctl,
  31 +       .ndo_select_queue    = mvneta_select_queue,
  32         .ndo_bpf             = mvneta_xdp,
  33         .ndo_xdp_xmit        = mvneta_xdp_xmit,
  34  };