On Sat, Oct 26, 2024 at 7:00 AM Michael Chan <michael.chan@xxxxxxxxxxxx> wrote:
>
> On Fri, Oct 25, 2024 at 12:24 PM Andy Gospodarek
> <andrew.gospodarek@xxxxxxxxxxxx> wrote:
Hi Andy,
Thank you so much for your review!
> >
> > On Thu, Oct 24, 2024 at 10:02:30PM -0700, Michael Chan wrote:
> > > On Tue, Oct 22, 2024 at 9:24 AM Taehee Yoo <ap420073@xxxxxxxxx> wrote:
> > > >
> > > > NICs that uses bnxt_en driver supports tcp-data-split feature by the
> > > > name of HDS(header-data-split).
> > > > But there is no implementation for the HDS to enable or disable by
> > > > ethtool.
> > > > Only getting the current HDS status is implemented and The HDS is just
> > > > automatically enabled only when either LRO, HW-GRO, or JUMBO is enabled.
> > > > The hds_threshold follows rx-copybreak value. and it was unchangeable.
> > > >
> > > > This implements `ethtool -G <interface name> tcp-data-split <value>`
> > > > command option.
> > > > The value can be <on>, <off>, and <auto> but the <auto> will be
> > > > automatically changed to <on>.
> > > >
> > > > HDS feature relies on the aggregation ring.
> > > > So, if HDS is enabled, the bnxt_en driver initializes the aggregation
> > > > ring.
> > > > This is the reason why BNXT_FLAG_AGG_RINGS contains HDS condition.
> > > >
> > > > Tested-by: Stanislav Fomichev <sdf@xxxxxxxxxxx>
> > > > Signed-off-by: Taehee Yoo <ap420073@xxxxxxxxx>
> > > > ---
> > > >
> > > > v4:
> > > > - Do not support disable tcp-data-split.
> > > > - Add Test tag from Stanislav.
> > > >
> > > > v3:
> > > > - No changes.
> > > >
> > > > v2:
> > > > - Do not set hds_threshold to 0.
> > > >
> > > > drivers/net/ethernet/broadcom/bnxt/bnxt.c | 8 +++-----
> > > > drivers/net/ethernet/broadcom/bnxt/bnxt.h | 5 +++--
> > > > drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c | 13 +++++++++++++
> > > > 3 files changed, 19 insertions(+), 7 deletions(-)
> > > >
> > > > diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> > > > index 0f5fe9ba691d..91ea42ff9b17 100644
> > > > --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> > > > +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> > >
> > > > @@ -6420,15 +6420,13 @@ static int bnxt_hwrm_vnic_set_hds(struct bnxt *bp, struct bnxt_vnic_info *vnic)
> > > >
> > > > req->flags = cpu_to_le32(VNIC_PLCMODES_CFG_REQ_FLAGS_JUMBO_PLACEMENT);
> > > > req->enables = cpu_to_le32(VNIC_PLCMODES_CFG_REQ_ENABLES_JUMBO_THRESH_VALID);
> > > > + req->jumbo_thresh = cpu_to_le16(bp->rx_buf_use_size);
> > > >
> > > > - if (BNXT_RX_PAGE_MODE(bp)) {
> > > > - req->jumbo_thresh = cpu_to_le16(bp->rx_buf_use_size);
> > >
> > > Please explain why this "if" condition is removed.
> > > BNXT_RX_PAGE_MODE() means that we are in XDP mode and we currently
> > > don't support HDS in XDP mode. Added Andy Gospo to CC so he can also
> > > comment.
> > >
> >
> > In bnxt_set_rx_skb_mode we set BNXT_FLAG_RX_PAGE_MODE and clear
> > BNXT_FLAG_AGG_RINGS
>
> The BNXT_FLAG_AGG_RINGS flag is true if the JUMBO, GRO, or LRO flag is
> set. So even though it is initially cleared in
> bnxt_set_rx_skb_mode(), we'll set the JUMBO flag if we are in
> multi-buffer XDP mode. Again, we don't enable HDS in any XDP mode so
> I think we need to keep the original logic here to skip setting the
> HDS threshold if BNXT_FLAG_RX_PAGE_MODE is set.
I thought the HDS is disallowed only when single-buffer XDP is set.
By this series, Core API disallows tcp-data-split only when
single-buffer XDP is set, but it allows tcp-data-split to set when
multi-buffer XDP is set.
+ if (kernel_ringparam.tcp_data_split == ETHTOOL_TCP_DATA_SPLIT_ENABLED &&
+ 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;
+ }
I think other drivers would allow tcp-data-split on multi buffer XDP,
so I wouldn't like to remove this condition check code.
I will not set HDS if XDP is set in the bnxt_hwrm_vnic_set_hds()
In addition, I think we need to add a condition to check XDP is set in
bnxt_set_ringparam().
>
> > , so this should work. The only issue is that we
> > have spots in the driver where we check BNXT_RX_PAGE_MODE(bp) to
> > indicate that XDP single-buffer mode is enabled on the device.
> >
> > If you need to respin this series I would prefer that the change is like
> > below to key off the page mode being disabled and BNXT_FLAG_AGG_RINGS
> > being enabled to setup HDS. This will serve as a reminder that this is
> > for XDP.
> >
> > @@ -6418,15 +6418,13 @@ static int bnxt_hwrm_vnic_set_hds(struct bnxt *bp, struct bnxt_vnic_info *vnic)
> >
> > req->flags = cpu_to_le32(VNIC_PLCMODES_CFG_REQ_FLAGS_JUMBO_PLACEMENT);
> > req->enables = cpu_to_le32(VNIC_PLCMODES_CFG_REQ_ENABLES_JUMBO_THRESH_VALID);
> > + req->jumbo_thresh = cpu_to_le16(bp->rx_buf_use_size);
> >
> > - if (BNXT_RX_PAGE_MODE(bp)) {
> > - req->jumbo_thresh = cpu_to_le16(bp->rx_buf_use_size);
> > - } else {
> > + if (!BNXT_RX_PAGE_MODE(bp) && (bp->flags & BNXT_FLAG_AGG_RINGS)) {
> > req->flags |= cpu_to_le32(VNIC_PLCMODES_CFG_REQ_FLAGS_HDS_IPV4 |
> > VNIC_PLCMODES_CFG_REQ_FLAGS_HDS_IPV6);
> > req->enables |=
> > cpu_to_le32(VNIC_PLCMODES_CFG_REQ_ENABLES_HDS_THRESHOLD_VALID);
> > - req->jumbo_thresh = cpu_to_le16(bp->rx_copy_thresh);
> > req->hds_threshold = cpu_to_le16(bp->rx_copy_thresh);
> > }
> > req->vnic_id = cpu_to_le32(vnic->fw_vnic_id);
> >
Thanks a lot!
Taehee Yoo
