[PATCH net 2/6] xsk: pass TX metadata pointer by reference
From: Stanislav Fomichev <hidden>
Date: 2026-07-27 16:20:02
Also in:
bpf, intel-wired-lan, linux-arm-kernel, linux-rdma, lkml
Subsystem:
intel ethernet drivers, libeth common ethernet library, mellanox mlx5 core vpi driver, networking drivers, networking [general], stmmac ethernet driver, the rest, xdp (express data path), xdp sockets (af_xdp) · Maintainers:
Tony Nguyen, Przemek Kitszel, Alexander Lobakin, Saeed Mahameed, Leon Romanovsky, Tariq Toukan, Mark Bloch, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Maxime Chevallier, Linus Torvalds, Alexei Starovoitov, Daniel Borkmann, Jesper Dangaard Brouer, John Fastabend, Magnus Karlsson, Maciej Fijalkowski
Completion handling needs to know whether a timestamp was requested when
the metadata was processed. Let xsk_tx_metadata_request() update the
caller's metadata pointer so that decision can be carried forward without
rereading user-controlled flags.
This only changes the interface; behavior remains unchanged.
Fixes: ca4419f15abd ("xsk: Add launch time hardware offload support to XDP Tx metadata")
Cc: Cen Zhang (Microsoft) <redacted>
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
---
drivers/net/ethernet/intel/igc/igc_main.c | 2 +-
drivers/net/ethernet/mellanox/mlx5/core/en.h | 2 +-
drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c | 14 +++++++++-----
drivers/net/ethernet/mellanox/mlx5/core/en/xdp.h | 4 ++--
.../net/ethernet/mellanox/mlx5/core/en/xsk/tx.c | 2 +-
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 2 +-
include/net/libeth/xsk.h | 2 +-
include/net/xdp_sock.h | 8 +++++---
8 files changed, 21 insertions(+), 15 deletions(-)
diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c
index 2c9e2dfd8499..5a18d00deb4f 100644
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c@@ -3082,7 +3082,7 @@ static void igc_xdp_xmit_zc(struct igc_ring *ring) meta_req.tx_buffer = bi; meta_req.meta = meta; meta_req.used_desc = 0; - xsk_tx_metadata_request(meta, &igc_xsk_tx_metadata_ops, + xsk_tx_metadata_request(&meta, &igc_xsk_tx_metadata_ops, &meta_req); /* xsk_tx_metadata_request() may have updated next_to_use */
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en.h b/drivers/net/ethernet/mellanox/mlx5/core/en.h
index d507289096c2..e12cb41c4b97 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h@@ -483,7 +483,7 @@ typedef int (*mlx5e_fp_xmit_xdp_frame_check)(struct mlx5e_xdpsq *); typedef bool (*mlx5e_fp_xmit_xdp_frame)(struct mlx5e_xdpsq *, struct mlx5e_xmit_data *, int, - struct xsk_tx_metadata *); + struct xsk_tx_metadata **); struct mlx5e_xdpsq { /* data path */
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
index d8c7cb8837d7..dac5e9d4c8bd 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c@@ -452,11 +452,11 @@ INDIRECT_CALLABLE_SCOPE int mlx5e_xmit_xdp_frame_check_mpwqe(struct mlx5e_xdpsq INDIRECT_CALLABLE_SCOPE bool mlx5e_xmit_xdp_frame(struct mlx5e_xdpsq *sq, struct mlx5e_xmit_data *xdptxd, - int check_result, struct xsk_tx_metadata *meta); + int check_result, struct xsk_tx_metadata **meta); INDIRECT_CALLABLE_SCOPE bool mlx5e_xmit_xdp_frame_mpwqe(struct mlx5e_xdpsq *sq, struct mlx5e_xmit_data *xdptxd, - int check_result, struct xsk_tx_metadata *meta) + int check_result, struct xsk_tx_metadata **meta) { struct mlx5e_tx_mpwqe *session = &sq->mpwqe; struct mlx5e_xdpsq_stats *stats = sq->stats;
@@ -504,7 +504,10 @@ mlx5e_xmit_xdp_frame_mpwqe(struct mlx5e_xdpsq *sq, struct mlx5e_xmit_data *xdptx * and it's safe to complete it at any time. */ mlx5e_xdp_mpwqe_session_start(sq); - xsk_tx_metadata_request(meta, &mlx5e_xsk_tx_metadata_ops, &session->wqe->eth); + if (meta) + xsk_tx_metadata_request(meta, + &mlx5e_xsk_tx_metadata_ops, + &session->wqe->eth); } mlx5e_xdp_mpwqe_add_dseg(sq, p, stats);
@@ -535,7 +538,7 @@ INDIRECT_CALLABLE_SCOPE int mlx5e_xmit_xdp_frame_check(struct mlx5e_xdpsq *sq) INDIRECT_CALLABLE_SCOPE bool mlx5e_xmit_xdp_frame(struct mlx5e_xdpsq *sq, struct mlx5e_xmit_data *xdptxd, - int check_result, struct xsk_tx_metadata *meta) + int check_result, struct xsk_tx_metadata **meta) { struct mlx5e_xmit_data_frags *xdptxdf = container_of(xdptxd, struct mlx5e_xmit_data_frags, xd);
@@ -649,7 +652,8 @@ mlx5e_xmit_xdp_frame(struct mlx5e_xdpsq *sq, struct mlx5e_xmit_data *xdptxd, sq->pc += num_wqebbs; - xsk_tx_metadata_request(meta, &mlx5e_xsk_tx_metadata_ops, eseg); + if (meta) + xsk_tx_metadata_request(meta, &mlx5e_xsk_tx_metadata_ops, eseg); sq->doorbell_cseg = cseg;
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.h b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.h
index 3c54f8962664..5b8f4094d553 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.h@@ -114,11 +114,11 @@ extern const struct xsk_tx_metadata_ops mlx5e_xsk_tx_metadata_ops; INDIRECT_CALLABLE_DECLARE(bool mlx5e_xmit_xdp_frame_mpwqe(struct mlx5e_xdpsq *sq, struct mlx5e_xmit_data *xdptxd, int check_result, - struct xsk_tx_metadata *meta)); + struct xsk_tx_metadata **meta)); INDIRECT_CALLABLE_DECLARE(bool mlx5e_xmit_xdp_frame(struct mlx5e_xdpsq *sq, struct mlx5e_xmit_data *xdptxd, int check_result, - struct xsk_tx_metadata *meta)); + struct xsk_tx_metadata **meta)); INDIRECT_CALLABLE_DECLARE(int mlx5e_xmit_xdp_frame_check_mpwqe(struct mlx5e_xdpsq *sq)); INDIRECT_CALLABLE_DECLARE(int mlx5e_xmit_xdp_frame_check(struct mlx5e_xdpsq *sq));
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c
index 8aeab4b21035..3d19dad8f868 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c@@ -105,7 +105,7 @@ bool mlx5e_xsk_tx(struct mlx5e_xdpsq *sq, unsigned int budget) ret = INDIRECT_CALL_2(sq->xmit_xdp_frame, mlx5e_xmit_xdp_frame_mpwqe, mlx5e_xmit_xdp_frame, sq, &xdptxd, - check_result, meta); + check_result, &meta); if (unlikely(!ret)) { if (sq->mpwqe.wqe) mlx5e_xdp_mpwqe_complete(sq);
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 151c77713025..3f5111969c41 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c@@ -2747,7 +2747,7 @@ static bool stmmac_xdp_xmit_zc(struct stmmac_priv *priv, u32 queue, u32 budget) meta_req.set_ic = &set_ic; meta_req.tbs = tx_q->tbs; meta_req.edesc = &tx_q->dma_entx[entry]; - xsk_tx_metadata_request(meta, &stmmac_xsk_tx_metadata_ops, + xsk_tx_metadata_request(&meta, &stmmac_xsk_tx_metadata_ops, &meta_req); if (set_ic) { tx_q->tx_count_frames = 0;
diff --git a/include/net/libeth/xsk.h b/include/net/libeth/xsk.h
index 82b5d21aae87..e2fa6bf6b1b3 100644
--- a/include/net/libeth/xsk.h
+++ b/include/net/libeth/xsk.h@@ -205,7 +205,7 @@ __libeth_xsk_xmit_fill_buf_md(const struct xdp_desc *xdesc, BUILD_BUG_ON(!__builtin_constant_p(tmo == libeth_xsktmo)); tmo = tmo == libeth_xsktmo ? &__libeth_xsktmo : tmo; - xsk_tx_metadata_request(ctx.meta, tmo, &desc); + xsk_tx_metadata_request(&ctx.meta, tmo, &desc); return desc; }
diff --git a/include/net/xdp_sock.h b/include/net/xdp_sock.h
index 8b51876efbed..06c081feff42 100644
--- a/include/net/xdp_sock.h
+++ b/include/net/xdp_sock.h@@ -153,17 +153,19 @@ static inline void xsk_tx_metadata_to_compl(struct xsk_tx_metadata *meta, /** * xsk_tx_metadata_request - Evaluate AF_XDP TX metadata at submission * and call appropriate xsk_tx_metadata_ops operation. - * @meta: pointer to AF_XDP metadata area + * @pmeta: pointer to pointer to AF_XDP metadata area * @ops: pointer to struct xsk_tx_metadata_ops * @priv: pointer to driver-private aread * * This function should be called by the networking device when * it prepares AF_XDP egress packet. */ -static inline void xsk_tx_metadata_request(const struct xsk_tx_metadata *meta, +static inline void xsk_tx_metadata_request(struct xsk_tx_metadata **pmeta, const struct xsk_tx_metadata_ops *ops, void *priv) { + const struct xsk_tx_metadata *meta = *pmeta; + if (!meta) return;
@@ -231,7 +233,7 @@ static inline void xsk_tx_metadata_to_compl(struct xsk_tx_metadata *meta, { } -static inline void xsk_tx_metadata_request(struct xsk_tx_metadata *meta, +static inline void xsk_tx_metadata_request(struct xsk_tx_metadata **pmeta, const struct xsk_tx_metadata_ops *ops, void *priv) {
--
2.53.0-Meta