[PATCH net-next v4 1/2] net/mlx5: DMA-sync earlier in mlx5e_skb_from_cqe_mpwrq_nonlinear
From: Christoph Paasch via B4 Relay <devnull+cpaasch.openai.com@kernel.org>
Date: 2025-08-29 03:36:42
Also in:
b4-sent, bpf, linux-rdma
Subsystem:
mellanox ethernet driver (mlx5e), mellanox mlx5 core vpi driver, networking drivers, the rest · Maintainers:
Saeed Mahameed, Tariq Toukan, Mark Bloch, Leon Romanovsky, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
From: Christoph Paasch <redacted> Doing the call to dma_sync_single_for_cpu() earlier will allow us to adjust headlen based on the actual size of the protocol headers. Doing this earlier means that we don't need to call mlx5e_copy_skb_header() anymore and rather can call skb_copy_to_linear_data() directly. Signed-off-by: Christoph Paasch <redacted> --- drivers/net/ethernet/mellanox/mlx5/core/en_rx.c | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
index b8c609d91d11bd315e8fb67f794a91bd37cd28c0..8bedbda522808cbabc8e62ae91a8c25d66725ebb 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c@@ -2005,17 +2005,19 @@ mlx5e_skb_from_cqe_mpwrq_nonlinear(struct mlx5e_rq *rq, struct mlx5e_mpw_info *w struct skb_shared_info *sinfo; unsigned int truesize = 0; struct bpf_prog *prog; + void *va, *head_addr; struct sk_buff *skb; u32 linear_frame_sz; u16 linear_data_len; u16 linear_hr; - void *va; prog = rcu_dereference(rq->xdp_prog); + head_addr = netmem_address(head_page->netmem) + head_offset; + if (prog) { /* area for bpf_xdp_[store|load]_bytes */ - net_prefetchw(netmem_address(frag_page->netmem) + frag_offset); + net_prefetchw(head_addr); if (unlikely(mlx5e_page_alloc_fragmented(rq->page_pool, &wi->linear_page))) { rq->stats->buff_alloc_err++;
@@ -2028,6 +2030,8 @@ mlx5e_skb_from_cqe_mpwrq_nonlinear(struct mlx5e_rq *rq, struct mlx5e_mpw_info *w linear_data_len = 0; linear_frame_sz = MLX5_SKB_FRAG_SZ(linear_hr + MLX5E_RX_MAX_HEAD); } else { + dma_addr_t addr; + skb = napi_alloc_skb(rq->cq.napi, ALIGN(MLX5E_RX_MAX_HEAD, sizeof(long))); if (unlikely(!skb)) {
@@ -2039,6 +2043,10 @@ mlx5e_skb_from_cqe_mpwrq_nonlinear(struct mlx5e_rq *rq, struct mlx5e_mpw_info *w net_prefetchw(va); /* xdp_frame data area */ net_prefetchw(skb->data); + addr = page_pool_get_dma_addr_netmem(head_page->netmem); + dma_sync_single_for_cpu(rq->pdev, addr + head_offset, headlen, + rq->buff.map_dir); + frag_offset += headlen; byte_cnt -= headlen; linear_hr = skb_headroom(skb);
@@ -2117,8 +2125,6 @@ mlx5e_skb_from_cqe_mpwrq_nonlinear(struct mlx5e_rq *rq, struct mlx5e_mpw_info *w } __pskb_pull_tail(skb, headlen); } else { - dma_addr_t addr; - if (xdp_buff_has_frags(&mxbuf->xdp)) { struct mlx5e_frag_page *pagep;
@@ -2133,9 +2139,8 @@ mlx5e_skb_from_cqe_mpwrq_nonlinear(struct mlx5e_rq *rq, struct mlx5e_mpw_info *w while (++pagep < frag_page); } /* copy header */ - addr = page_pool_get_dma_addr_netmem(head_page->netmem); - mlx5e_copy_skb_header(rq, skb, head_page->netmem, addr, - head_offset, head_offset, headlen); + skb_copy_to_linear_data(skb, head_addr, headlen); + /* skb linear part was allocated with headlen and aligned to long */ skb->tail += headlen; skb->len += headlen;
--
2.50.1