[Intel-wired-lan] [PATCH net 2/6] xsk: pass TX metadata pointer by reference

Stanislav Fomichev <[email protected]> Mon, 27 Jul 2026 09:19:55 -0700
Newsgroups org.osuosl.intel-wired-lan,org.infradead.lists.linux-arm-kernel,org.kernel.vger.bpf,org.kernel.vger.linux-kernel,org.kernel.vger.linux-rdma,org.kernel.vger.netdev
Message-ID <[email protected]>
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) <[email protected]>
Signed-off-by: Stanislav Fomichev <[email protected]>
---
 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