Subject: Re: [PATCH v3 iwl-net 3/3] ice: stop storing XDP verdict within ice_rx_buf

From: Simon Horman <[email-masked]>
Date: Mon, 20 Jan 2025 16:37:55 +0000

On Mon, Jan 20, 2025 at 04:50:16PM +0100, Maciej Fijalkowski wrote:
> Idea behind having ice_rx_buf::act was to simplify and speed up the Rx
> data path by walking through buffers that were representing cleaned HW
> Rx descriptors. Since it caused us a major headache recently and we
> rolled back to old approach that 'puts' Rx buffers right after running
> XDP prog/creating skb, this is useless now and should be removed.
> 
> Get rid of ice_rx_buf::act and related logic. We still need to take care
> of a corner case where XDP program releases a particular fragment.
> 
> Make ice_run_xdp() to return its result and use it within
> ice_put_rx_mbuf().
> 
> Fixes: 2fba7dc5157b ("ice: Add support for XDP multi-buffer on Rx side")
> Reviewed-by: Przemek Kitszel <[email-masked]>
> Signed-off-by: Maciej Fijalkowski <[email-masked]>
> ---
>  drivers/net/ethernet/intel/ice/ice_txrx.c     | 60 +++++++++++--------
>  drivers/net/ethernet/intel/ice/ice_txrx.h     |  1 -
>  drivers/net/ethernet/intel/ice/ice_txrx_lib.h | 43 -------------
>  3 files changed, 35 insertions(+), 69 deletions(-)
> 
> diff --git a/drivers/net/ethernet/intel/ice/ice_txrx.c b/drivers/net/ethernet/intel/ice/ice_txrx.c
> index 9aa53ad2d8f2..77d75664c14d 100644
> --- a/drivers/net/ethernet/intel/ice/ice_txrx.c
> +++ b/drivers/net/ethernet/intel/ice/ice_txrx.c
> @@ -532,10 +532,10 @@ int ice_setup_rx_ring(struct ice_rx_ring *rx_ring)
>   *
>   * Returns any of ICE_XDP_{PASS, CONSUMED, TX, REDIR}
>   */
> -static void
> +static u32
>  ice_run_xdp(struct ice_rx_ring *rx_ring, struct xdp_buff *xdp,
>  	    struct bpf_prog *xdp_prog, struct ice_tx_ring *xdp_ring,
> -	    struct ice_rx_buf *rx_buf, union ice_32b_rx_flex_desc *eop_desc)
> +	    union ice_32b_rx_flex_desc *eop_desc)
>  {
>  	unsigned int ret = ICE_XDP_PASS;
>  	u32 act;

nit: The Kernel doc for ice_run_xdp should also be updated to no
     longer document the rx_buf parameter.

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