Re: [PATCH RESEND bpf-next 06/15] ice: Support HW timestamp hint

From: Stanislav Fomichev <sdf@google.com>
To: Larysa Zaremba <larysa.zaremba@intel.com>
Cc: bpf@vger.kernel.org, Alexei Starovoitov <ast@kernel.org>,
	 Daniel Borkmann <daniel@iogearbox.net>,
	Andrii Nakryiko <andrii@kernel.org>,
	 Jakub Kicinski <kuba@kernel.org>,
	Martin KaFai Lau <martin.lau@linux.dev>,
	Song Liu <song@kernel.org>,  Yonghong Song <yhs@fb.com>,
	John Fastabend <john.fastabend@gmail.com>,
	KP Singh <kpsingh@kernel.org>,  Jiri Olsa <jolsa@kernel.org>,
	Jesse Brandeburg <jesse.brandeburg@intel.com>,
	 Tony Nguyen <anthony.l.nguyen@intel.com>,
	Anatoly Burakov <anatoly.burakov@intel.com>,
	 Jesper Dangaard Brouer <brouer@redhat.com>,
	Alexander Lobakin <alexandr.lobakin@intel.com>,
	 Magnus Karlsson <magnus.karlsson@gmail.com>,
	Maryam Tahhan <mtahhan@redhat.com>,
	 xdp-hints@xdp-project.net, netdev@vger.kernel.org,
	 intel-wired-lan@lists.osuosl.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH RESEND bpf-next 06/15] ice: Support HW timestamp hint
Date: Fri, 12 May 2023 11:19:53 -0700	[thread overview]
Message-ID: <ZF6DHOtnr/AfYxML@google.com> (raw)
In-Reply-To: <20230512152607.992209-7-larysa.zaremba@intel.com>

On 05/12, Larysa Zaremba wrote:
> Use previously refactored code and create a function
> that allows XDP code to read HW timestamp.
> 
> HW timestamp is the first supported hint in the driver,
> so also add xdp_metadata_ops.
> 
> Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com>
> ---
>  drivers/net/ethernet/intel/ice/ice.h          |  2 ++
>  drivers/net/ethernet/intel/ice/ice_main.c     |  1 +
>  drivers/net/ethernet/intel/ice/ice_txrx_lib.c | 22 +++++++++++++++++++
>  3 files changed, 25 insertions(+)
> 
> diff --git a/drivers/net/ethernet/intel/ice/ice.h b/drivers/net/ethernet/intel/ice/ice.h
> index aa32111afd6e..ba1bb8392db1 100644
> --- a/drivers/net/ethernet/intel/ice/ice.h
> +++ b/drivers/net/ethernet/intel/ice/ice.h
> @@ -962,4 +962,6 @@ static inline void ice_clear_rdma_cap(struct ice_pf *pf)
>  	set_bit(ICE_FLAG_UNPLUG_AUX_DEV, pf->flags);
>  	clear_bit(ICE_FLAG_RDMA_ENA, pf->flags);
>  }
> +
> +extern const struct xdp_metadata_ops ice_xdp_md_ops;
>  #endif /* _ICE_H_ */
> diff --git a/drivers/net/ethernet/intel/ice/ice_main.c b/drivers/net/ethernet/intel/ice/ice_main.c
> index a1f7c8edc22f..cda6c4a80737 100644
> --- a/drivers/net/ethernet/intel/ice/ice_main.c
> +++ b/drivers/net/ethernet/intel/ice/ice_main.c
> @@ -3378,6 +3378,7 @@ static void ice_set_ops(struct ice_vsi *vsi)
>  
>  	netdev->netdev_ops = &ice_netdev_ops;
>  	netdev->udp_tunnel_nic_info = &pf->hw.udp_tunnel_nic;
> +	netdev->xdp_metadata_ops = &ice_xdp_md_ops;
>  	ice_set_ethtool_ops(netdev);
>  
>  	if (vsi->type != ICE_VSI_PF)
> diff --git a/drivers/net/ethernet/intel/ice/ice_txrx_lib.c b/drivers/net/ethernet/intel/ice/ice_txrx_lib.c
> index 2515f5f7a2b6..e9589cadf811 100644
> --- a/drivers/net/ethernet/intel/ice/ice_txrx_lib.c
> +++ b/drivers/net/ethernet/intel/ice/ice_txrx_lib.c
> @@ -537,3 +537,25 @@ void ice_finalize_xdp_rx(struct ice_tx_ring *xdp_ring, unsigned int xdp_res,
>  			spin_unlock(&xdp_ring->tx_lock);
>  	}
>  }
> +
> +/**
> + * ice_xdp_rx_hw_ts - HW timestamp XDP hint handler
> + * @ctx: XDP buff pointer
> + * @ts_ns: destination address
> + *
> + * Copy HW timestamp (if available) to the destination address.
> + */
> +static int ice_xdp_rx_hw_ts(const struct xdp_md *ctx, u64 *ts_ns)
> +{
> +	const struct ice_xdp_buff *xdp_ext = (void *)ctx;
> +
> +	if (!ice_ptp_copy_rx_hwts_from_desc(xdp_ext->rx_ring,
> +					    xdp_ext->eop_desc, ts_ns))
> +		return -EOPNOTSUPP;

Per Jesper's recent update, should this be ENODATA?