On Thu, Dec 19, 2024 at 11:25 AM Jakub Kicinski <kuba@xxxxxxxxxx> wrote:
>
> On Wed, 18 Dec 2024 14:45:24 +0000 Taehee Yoo wrote:
> > + if (tcp_data_split == ETHTOOL_TCP_DATA_SPLIT_DISABLED && hds_config_mod)
> > + return -EOPNOTSUPP;
>
> I think ethtool ops generally return -EINVAL when param not supported.
> EOPNOTSUPP means entire op is not supported (again, that's just how
> ethtool ops generally work, not a kernel-wide rule).
Thanks! I will use -EINVAL instead of EOPNOTSUPP.
>
> > + if (tcp_data_split == ETHTOOL_TCP_DATA_SPLIT_ENABLED &&
> > + hds_config_mod && BNXT_RX_PAGE_MODE(bp)) {
>
> Looks like patch 4 adds this check in the core. I think adding the
> check in the core can be a separate patch. If you put it before this
> patch in the series this bnxt check can be removed?
>
> I mean this chunk in the core:
>
> + hds_config_mod = old_hds_config != kernel_ringparam.tcp_data_split;
> + if (kernel_ringparam.tcp_data_split == ETHTOOL_TCP_DATA_SPLIT_ENABLED &&
> + hds_config_mod && dev_xdp_sb_prog_count(dev)) {
> + NL_SET_ERR_MSG(info->extack,
> + "tcp-data-split can not be enabled with single buffer XDP");
> + return -EINVAL;
> + }
>
Right, The core checks single buffer XDP.
But there was a review that bnxt_en driver doesn't support both
single and multi buffer XDP if HDS is in use.
So, this is the reason why logic exists.
> It's currently in the hds-thresh patch but really it's unrelated
> to the threshold..
Thanks, I will move this code to a HDS related patch, not hds-threshold,
or create new patch for this.
>
> > + NL_SET_ERR_MSG_MOD(extack, "tcp-data-split is disallowed when XDP is attached");
> > + return -EOPNOTSUPP;
> > + }
> > +
> > if (netif_running(dev))
> > bnxt_close_nic(bp, false, false);
> >
> > + if (hds_config_mod) {
> > + if (tcp_data_split == ETHTOOL_TCP_DATA_SPLIT_ENABLED)
> > + bp->flags |= BNXT_FLAG_HDS;
> > + else if (tcp_data_split == ETHTOOL_TCP_DATA_SPLIT_UNKNOWN)
> > + bp->flags &= ~BNXT_FLAG_HDS;
> > + }
> > +
> > bp->rx_ring_size = ering->rx_pending;
> > bp->tx_ring_size = ering->tx_pending;
> > bnxt_set_ring_params(bp);
> > @@ -5354,6 +5374,7 @@ const struct ethtool_ops bnxt_ethtool_ops = {
> > ETHTOOL_COALESCE_STATS_BLOCK_USECS |
> > ETHTOOL_COALESCE_USE_ADAPTIVE_RX |
> > ETHTOOL_COALESCE_USE_CQE,
> > + .supported_ring_params = ETHTOOL_RING_USE_TCP_DATA_SPLIT,
> > .get_link_ksettings = bnxt_get_link_ksettings,
> > .set_link_ksettings = bnxt_set_link_ksettings,
> > .get_fec_stats = bnxt_get_fec_stats,
> > diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
> > index f88b641533fc..1bfff7f29310 100644
> > --- a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
> > +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
> > @@ -395,6 +395,10 @@ static int bnxt_xdp_set(struct bnxt *bp, struct bpf_prog *prog)
> > bp->dev->mtu, BNXT_MAX_PAGE_MODE_MTU);
> > return -EOPNOTSUPP;
> > }
> > + if (prog && bp->flags & BNXT_FLAG_HDS) {
> > + netdev_warn(dev, "XDP is disallowed when HDS is enabled.\n");
> > + return -EOPNOTSUPP;
> > + }
>
> And this check should also live in the core, now that core has access
> to dev->ethtool->hds_config ? I think you can add this check to the
> core in the same patch as the chunk referred to above.
The bnxt_en disallows setting up both single and multi buffer XDP, but core
checks only single buffer XDP. So, if multi buffer XDP is attaching to
the bnxt_en driver when HDS is enabled, the core can't filter it.
Thanks a lot!
Taehee Yoo
