4 files changed, 48 insertions, 5 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.h b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.h
index 307b923a1361..cab0e93497ae 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.h
@@ -5,6 +5,7 @@
 #define __MLX5_EN_XSK_RX_H__
 
 #include "en.h"
+#include <net/xdp_sock.h>
 
 /* RX data path */
 
@@ -24,4 +25,17 @@ struct sk_buff *mlx5e_xsk_skb_from_cqe_linear(struct mlx5e_rq *rq,
 					      struct mlx5e_wqe_frag_info *wi,
 					      u32 cqe_bcnt);
 
+static inline bool mlx5e_xsk_update_rx_wakeup(struct mlx5e_rq *rq, bool alloc_err)
+{
+	if (!xsk_umem_uses_need_wakeup(rq->umem))
+		return alloc_err;
+
+	if (unlikely(alloc_err))
+		xsk_set_rx_need_wakeup(rq->umem);
+	else
+		xsk_clear_rx_need_wakeup(rq->umem);
+
+	return false;
+}
+
 #endif /* __MLX5_EN_XSK_RX_H__ */
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.h b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.h
index 9c505158b975..79b487d89757 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.h
@@ -5,6 +5,7 @@
 #define __MLX5_EN_XSK_TX_H__
 
 #include "en.h"
+#include <net/xdp_sock.h>
 
 /* TX data path */
 
@@ -12,4 +13,15 @@ int mlx5e_xsk_wakeup(struct net_device *dev, u32 qid, u32 flags);
 
 bool mlx5e_xsk_tx(struct mlx5e_xdpsq *sq, unsigned int budget);
 
+static inline void mlx5e_xsk_update_tx_wakeup(struct mlx5e_xdpsq *sq)
+{
+	if (!xsk_umem_uses_need_wakeup(sq->umem))
+		return;
+
+	if (sq->pc != sq->cc)
+		xsk_clear_tx_need_wakeup(sq->umem);
+	else
+		xsk_set_tx_need_wakeup(sq->umem);
+}
+
 #endif /* __MLX5_EN_XSK_TX_H__ */
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
index 60570b442fff..fae0694d1cf8 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
@@ -692,8 +692,11 @@ bool mlx5e_post_rx_mpwqes(struct mlx5e_rq *rq)
 	rq->mpwqe.umr_in_progress += rq->mpwqe.umr_last_bulk;
 	rq->mpwqe.actual_wq_head   = head;
 
-	/* If XSK Fill Ring doesn't have enough frames, busy poll by
-	 * rescheduling the NAPI poll.
+	/* If XSK Fill Ring doesn't have enough frames, report the error, so
+	 * that one of the actions can be performed:
+	 * 1. If need_wakeup is used, signal that the application has to kick
+	 * the driver when it refills the Fill Ring.
+	 * 2. Otherwise, busy poll by rescheduling the NAPI poll.
 	 */
 	if (unlikely(alloc_err == -ENOMEM && rq->umem))
 		return true;
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c
index 6d16dee38ede..257a7c9f7a14 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c
@@ -33,6 +33,7 @@
 #include <linux/irq.h>
 #include "en.h"
 #include "en/xdp.h"
+#include "en/xsk/rx.h"
 #include "en/xsk/tx.h"
 
 static inline bool mlx5e_channel_no_affinity_change(struct mlx5e_channel *c)
@@ -83,10 +84,23 @@ void mlx5e_trigger_irq(struct mlx5e_icosq *sq)
 
 static bool mlx5e_napi_xsk_post(struct mlx5e_xdpsq *xsksq, struct mlx5e_rq *xskrq)
 {
-	bool busy_xsk = false;
-
+	bool busy_xsk = false, xsk_rx_alloc_err;
+
+	/* Handle the race between the application querying need_wakeup and the
+	 * driver setting it:
+	 * 1. Update need_wakeup both before and after the TX. If it goes to
+	 * "yes", it can only happen with the first update.
+	 * 2. If the application queried need_wakeup before we set it, the
+	 * packets will be transmitted anyway, even w/o a wakeup.
+	 * 3. Give a chance to clear need_wakeup after new packets were queued
+	 * for TX.
+	 */
+	mlx5e_xsk_update_tx_wakeup(xsksq);
 	busy_xsk |= mlx5e_xsk_tx(xsksq, MLX5E_TX_XSK_POLL_BUDGET);
-	busy_xsk |= xskrq->post_wqes(xskrq);
+	mlx5e_xsk_update_tx_wakeup(xsksq);
+
+	xsk_rx_alloc_err = xskrq->post_wqes(xskrq);
+	busy_xsk |= mlx5e_xsk_update_rx_wakeup(xskrq, xsk_rx_alloc_err);
 
 	return busy_xsk;
 }