From: Aya Levin ayal@nvidia.com
[ Upstream commit 19b43a432e3e47db656a8269a74b50aef826950c ]
When tx_port_ts is set, the driver diverts all UPD traffic over PTP port to a dedicated PTP-SQ. The SKBs are cached until the wire-CQE arrives. When the packet size is greater then MTU, the firmware might drop it and the packet won't be transmitted to the wire, hence the wire-CQE won't reach the driver. In this case the SKBs are accumulated in the SKB fifo. Add room check to consider the PTP-SQ SKB fifo, when the SKB fifo is full, driver stops the queue resulting in a TX timeout. Devlink TX-reporter can recover from it.
Fixes: 1880bc4e4a96 ("net/mlx5e: Add TX port timestamp support") Signed-off-by: Aya Levin ayal@nvidia.com Reviewed-by: Tariq Toukan tariqt@nvidia.com Signed-off-by: Saeed Mahameed saeedm@nvidia.com Link: https://lore.kernel.org/r/20221026135153.154807-5-saeed@kernel.org Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/mellanox/mlx5/core/en/ptp.h | 9 +++++++++ drivers/net/ethernet/mellanox/mlx5/core/en/txrx.h | 6 ++++++ drivers/net/ethernet/mellanox/mlx5/core/en_tx.c | 6 ++++++ 3 files changed, 21 insertions(+)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/ptp.h b/drivers/net/ethernet/mellanox/mlx5/core/en/ptp.h index 92dbbec472ec..f324a0c6f869 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/ptp.h +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/ptp.h @@ -6,6 +6,7 @@
#include "en.h" #include "en_stats.h" +#include "en/txrx.h" #include <linux/ptp_classify.h>
#define MLX5E_PTP_CHANNEL_IX 0 @@ -68,6 +69,14 @@ static inline bool mlx5e_use_ptpsq(struct sk_buff *skb) fk.ports.dst == htons(PTP_EV_PORT)); }
+static inline bool mlx5e_ptpsq_fifo_has_room(struct mlx5e_txqsq *sq) +{ + if (!sq->ptpsq) + return true; + + return mlx5e_skb_fifo_has_room(&sq->ptpsq->skb_fifo); +} + int mlx5e_ptp_open(struct mlx5e_priv *priv, struct mlx5e_params *params, u8 lag_port, struct mlx5e_ptp **cp); void mlx5e_ptp_close(struct mlx5e_ptp *c); diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/txrx.h b/drivers/net/ethernet/mellanox/mlx5/core/en/txrx.h index c208ea307bff..ff8ca7a7e103 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/txrx.h +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/txrx.h @@ -57,6 +57,12 @@ netdev_tx_t mlx5e_xmit(struct sk_buff *skb, struct net_device *dev); bool mlx5e_poll_tx_cq(struct mlx5e_cq *cq, int napi_budget); void mlx5e_free_txqsq_descs(struct mlx5e_txqsq *sq);
+static inline bool +mlx5e_skb_fifo_has_room(struct mlx5e_skb_fifo *fifo) +{ + return (*fifo->pc - *fifo->cc) < fifo->mask; +} + static inline bool mlx5e_wqc_has_room_for(struct mlx5_wq_cyc *wq, u16 cc, u16 pc, u16 n) { diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c index 27f791feb517..4d45150a3f8e 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c @@ -391,6 +391,11 @@ mlx5e_txwqe_complete(struct mlx5e_txqsq *sq, struct sk_buff *skb, if (unlikely(sq->ptpsq)) { mlx5e_skb_cb_hwtstamp_init(skb); mlx5e_skb_fifo_push(&sq->ptpsq->skb_fifo, skb); + if (!netif_tx_queue_stopped(sq->txq) && + !mlx5e_skb_fifo_has_room(&sq->ptpsq->skb_fifo)) { + netif_tx_stop_queue(sq->txq); + sq->stats->stopped++; + } skb_get(skb); }
@@ -867,6 +872,7 @@ bool mlx5e_poll_tx_cq(struct mlx5e_cq *cq, int napi_budget)
if (netif_tx_queue_stopped(sq->txq) && mlx5e_wqc_has_room_for(&sq->wq, sq->cc, sq->pc, sq->stop_room) && + mlx5e_ptpsq_fifo_has_room(sq) && !test_bit(MLX5E_SQ_STATE_RECOVERING, &sq->state)) { netif_tx_wake_queue(sq->txq); stats->wake++;