Re: [PATCH bpf-next v3 08/12] mxl4: Support RX XDP metadata

[Stanislav Fomichev <sdf@google.com>]

On Wed, Dec 7, 2022 at 10:09 PM Tariq Toukan <ttoukan.linux@gmail.com> wrote:
>
> Typo in title mxl4 -> mlx4.
> Preferably: net/mlx4_en.

Oh, I always have to fight with this. Somehow mxl feels more natural
:-) Thanks for spotting, will use net/mlx4_en instead. (presumably the
same should be for mlx5?)

> On 12/6/2022 4:45 AM, Stanislav Fomichev wrote:
> > RX timestamp and hash for now. Tested using the prog from the next
> > patch.
> >
> > Also enabling xdp metadata support; don't see why it's disabled,
> > there is enough headroom..
> >
> > Cc: Tariq Toukan <tariqt@nvidia.com>
> > Cc: John Fastabend <john.fastabend@gmail.com>
> > Cc: David Ahern <dsahern@gmail.com>
> > Cc: Martin KaFai Lau <martin.lau@linux.dev>
> > Cc: Jakub Kicinski <kuba@kernel.org>
> > Cc: Willem de Bruijn <willemb@google.com>
> > Cc: Jesper Dangaard Brouer <brouer@redhat.com>
> > Cc: Anatoly Burakov <anatoly.burakov@intel.com>
> > Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
> > Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
> > Cc: Maryam Tahhan <mtahhan@redhat.com>
> > Cc: xdp-hints@xdp-project.net
> > Cc: netdev@vger.kernel.org
> > Signed-off-by: Stanislav Fomichev <sdf@google.com>
> > ---
> >   drivers/net/ethernet/mellanox/mlx4/en_clock.c | 13 +++++--
> >   .../net/ethernet/mellanox/mlx4/en_netdev.c    | 10 +++++
> >   drivers/net/ethernet/mellanox/mlx4/en_rx.c    | 38 ++++++++++++++++++-
> >   drivers/net/ethernet/mellanox/mlx4/mlx4_en.h  |  1 +
> >   include/linux/mlx4/device.h                   |  7 ++++
> >   5 files changed, 64 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/net/ethernet/mellanox/mlx4/en_clock.c b/drivers/net/ethernet/mellanox/mlx4/en_clock.c
> > index 98b5ffb4d729..9e3b76182088 100644
> > --- a/drivers/net/ethernet/mellanox/mlx4/en_clock.c
> > +++ b/drivers/net/ethernet/mellanox/mlx4/en_clock.c
> > @@ -58,9 +58,7 @@ u64 mlx4_en_get_cqe_ts(struct mlx4_cqe *cqe)
> >       return hi | lo;
> >   }
> >
> > -void mlx4_en_fill_hwtstamps(struct mlx4_en_dev *mdev,
> > -                         struct skb_shared_hwtstamps *hwts,
> > -                         u64 timestamp)
> > +u64 mlx4_en_get_hwtstamp(struct mlx4_en_dev *mdev, u64 timestamp)
> >   {
> >       unsigned int seq;
> >       u64 nsec;
> > @@ -70,8 +68,15 @@ void mlx4_en_fill_hwtstamps(struct mlx4_en_dev *mdev,
> >               nsec = timecounter_cyc2time(&mdev->clock, timestamp);
> >       } while (read_seqretry(&mdev->clock_lock, seq));
> >
> > +     return ns_to_ktime(nsec);
> > +}
> > +
> > +void mlx4_en_fill_hwtstamps(struct mlx4_en_dev *mdev,
> > +                         struct skb_shared_hwtstamps *hwts,
> > +                         u64 timestamp)
> > +{
> >       memset(hwts, 0, sizeof(struct skb_shared_hwtstamps));
> > -     hwts->hwtstamp = ns_to_ktime(nsec);
> > +     hwts->hwtstamp = mlx4_en_get_hwtstamp(mdev, timestamp);
> >   }
> >
> >   /**
> > diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
> > index 8800d3f1f55c..1cb63746a851 100644
> > --- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
> > +++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
> > @@ -2855,6 +2855,11 @@ static const struct net_device_ops mlx4_netdev_ops = {
> >       .ndo_features_check     = mlx4_en_features_check,
> >       .ndo_set_tx_maxrate     = mlx4_en_set_tx_maxrate,
> >       .ndo_bpf                = mlx4_xdp,
> > +
> > +     .ndo_xdp_rx_timestamp_supported = mlx4_xdp_rx_timestamp_supported,
> > +     .ndo_xdp_rx_timestamp   = mlx4_xdp_rx_timestamp,
> > +     .ndo_xdp_rx_hash_supported = mlx4_xdp_rx_hash_supported,
> > +     .ndo_xdp_rx_hash        = mlx4_xdp_rx_hash,
> >   };
> >
> >   static const struct net_device_ops mlx4_netdev_ops_master = {
> > @@ -2887,6 +2892,11 @@ static const struct net_device_ops mlx4_netdev_ops_master = {
> >       .ndo_features_check     = mlx4_en_features_check,
> >       .ndo_set_tx_maxrate     = mlx4_en_set_tx_maxrate,
> >       .ndo_bpf                = mlx4_xdp,
> > +
> > +     .ndo_xdp_rx_timestamp_supported = mlx4_xdp_rx_timestamp_supported,
> > +     .ndo_xdp_rx_timestamp   = mlx4_xdp_rx_timestamp,
> > +     .ndo_xdp_rx_hash_supported = mlx4_xdp_rx_hash_supported,
> > +     .ndo_xdp_rx_hash        = mlx4_xdp_rx_hash,
> >   };
> >
> >   struct mlx4_en_bond {
> > diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
> > index 9c114fc723e3..1b8e1b2d8729 100644
> > --- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c
> > +++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
> > @@ -663,8 +663,40 @@ static int check_csum(struct mlx4_cqe *cqe, struct sk_buff *skb, void *va,
> >
> >   struct mlx4_xdp_buff {
> >       struct xdp_buff xdp;
> > +     struct mlx4_cqe *cqe;
> > +     struct mlx4_en_dev *mdev;
> > +     struct mlx4_en_rx_ring *ring;
> > +     struct net_device *dev;
> >   };
> >
> > +bool mlx4_xdp_rx_timestamp_supported(const struct xdp_md *ctx)
> > +{
> > +     struct mlx4_xdp_buff *_ctx = (void *)ctx;
> > +
> > +     return _ctx->ring->hwtstamp_rx_filter == HWTSTAMP_FILTER_ALL;
> > +}
> > +
> > +u64 mlx4_xdp_rx_timestamp(const struct xdp_md *ctx)
> > +{
> > +     struct mlx4_xdp_buff *_ctx = (void *)ctx;
> > +
> > +     return mlx4_en_get_hwtstamp(_ctx->mdev, mlx4_en_get_cqe_ts(_ctx->cqe));
> > +}
> > +
> > +bool mlx4_xdp_rx_hash_supported(const struct xdp_md *ctx)
> > +{
> > +     struct mlx4_xdp_buff *_ctx = (void *)ctx;
> > +
> > +     return _ctx->dev->features & NETIF_F_RXHASH;
> > +}
> > +
> > +u32 mlx4_xdp_rx_hash(const struct xdp_md *ctx)
> > +{
> > +     struct mlx4_xdp_buff *_ctx = (void *)ctx;
> > +
> > +     return be32_to_cpu(_ctx->cqe->immed_rss_invalid);
> > +}
> > +
> >   int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int budget)
> >   {
> >       struct mlx4_en_priv *priv = netdev_priv(dev);
> > @@ -781,8 +813,12 @@ int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int bud
> >                                               DMA_FROM_DEVICE);
> >
> >                       xdp_prepare_buff(&mxbuf.xdp, va - frags[0].page_offset,
> > -                                      frags[0].page_offset, length, false);
> > +                                      frags[0].page_offset, length, true);
> >                       orig_data = mxbuf.xdp.data;
> > +                     mxbuf.cqe = cqe;
> > +                     mxbuf.mdev = priv->mdev;
> > +                     mxbuf.ring = ring;
> > +                     mxbuf.dev = dev;
> >
> >                       act = bpf_prog_run_xdp(xdp_prog, &mxbuf.xdp);
> >
> > diff --git a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
> > index e132ff4c82f2..b7c0d4899ad7 100644
> > --- a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
> > +++ b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
> > @@ -792,6 +792,7 @@ int mlx4_en_netdev_event(struct notifier_block *this,
> >    * Functions for time stamping
> >    */
> >   u64 mlx4_en_get_cqe_ts(struct mlx4_cqe *cqe);
> > +u64 mlx4_en_get_hwtstamp(struct mlx4_en_dev *mdev, u64 timestamp);
> >   void mlx4_en_fill_hwtstamps(struct mlx4_en_dev *mdev,
> >                           struct skb_shared_hwtstamps *hwts,
> >                           u64 timestamp);
> > diff --git a/include/linux/mlx4/device.h b/include/linux/mlx4/device.h
> > index 6646634a0b9d..d5904da1d490 100644
> > --- a/include/linux/mlx4/device.h
> > +++ b/include/linux/mlx4/device.h
> > @@ -1585,4 +1585,11 @@ static inline int mlx4_get_num_reserved_uar(struct mlx4_dev *dev)
> >       /* The first 128 UARs are used for EQ doorbells */
> >       return (128 >> (PAGE_SHIFT - dev->uar_page_shift));
> >   }
> > +
> > +struct xdp_md;
> > +bool mlx4_xdp_rx_timestamp_supported(const struct xdp_md *ctx);
> > +u64 mlx4_xdp_rx_timestamp(const struct xdp_md *ctx);
> > +bool mlx4_xdp_rx_hash_supported(const struct xdp_md *ctx);
> > +u32 mlx4_xdp_rx_hash(const struct xdp_md *ctx);
> > +
>
> These are ethernet only functions, not known to the mlx4 core driver.
> Please move to mlx4_en.h, and use mlx4_en_xdp_*() prefix.

For sure, thanks for the review!

> >   #endif /* MLX4_DEVICE_H */