Patch "net/mlx5e: Fix SQ wake logic in ptp napi_poll context" has been added to the 5.15-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    net/mlx5e: Fix SQ wake logic in ptp napi_poll context

to the 5.15-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     net-mlx5e-fix-sq-wake-logic-in-ptp-napi_poll-context.patch
and it can be found in the queue-5.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit bb5bd0966de5549d74aa2eefb61c3b50df6e9999
Author: Rahul Rameshbabu <rrameshbabu@xxxxxxxxxx>
Date:   Tue Feb 21 16:18:48 2023 -0800

    net/mlx5e: Fix SQ wake logic in ptp napi_poll context
    
    [ Upstream commit 7aa50380191635e5897a773f272829cc961a2be5 ]
    
    Check in the mlx5e_ptp_poll_ts_cq context if the ptp tx sq should be woken
    up. Before change, the ptp tx sq may never wake up if the ptp tx ts skb
    fifo is full when mlx5e_poll_tx_cq checks if the queue should be woken up.
    
    Fixes: 1880bc4e4a96 ("net/mlx5e: Add TX port timestamp support")
    Signed-off-by: Rahul Rameshbabu <rrameshbabu@xxxxxxxxxx>
    Reviewed-by: Tariq Toukan <tariqt@xxxxxxxxxx>
    Signed-off-by: Saeed Mahameed <saeedm@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/ptp.c b/drivers/net/ethernet/mellanox/mlx5/core/en/ptp.c
index 3a86f66d12955..ee95cc3a03786 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/ptp.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/ptp.c
@@ -126,6 +126,8 @@ static bool mlx5e_ptp_poll_ts_cq(struct mlx5e_cq *cq, int budget)
 	/* ensure cq space is freed before enabling more cqes */
 	wmb();
 
+	mlx5e_txqsq_wake(&ptpsq->txqsq);
+
 	return work_done == budget;
 }
 
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/txrx.h b/drivers/net/ethernet/mellanox/mlx5/core/en/txrx.h
index f5c872043bcbd..cf62d1f6d7f20 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/txrx.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/txrx.h
@@ -172,6 +172,8 @@ static inline u16 mlx5e_txqsq_get_next_pi(struct mlx5e_txqsq *sq, u16 size)
 	return pi;
 }
 
+void mlx5e_txqsq_wake(struct mlx5e_txqsq *sq);
+
 struct mlx5e_icosq_wqe_info {
 	u8 wqe_type;
 	u8 num_wqebbs;
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
index e18fa5ae0fd84..6813279b57f89 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
@@ -810,6 +810,17 @@ static void mlx5e_tx_wi_consume_fifo_skbs(struct mlx5e_txqsq *sq, struct mlx5e_t
 	}
 }
 
+void mlx5e_txqsq_wake(struct mlx5e_txqsq *sq)
+{
+	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);
+		sq->stats->wake++;
+	}
+}
+
 bool mlx5e_poll_tx_cq(struct mlx5e_cq *cq, int napi_budget)
 {
 	struct mlx5e_sq_stats *stats;
@@ -909,13 +920,7 @@ bool mlx5e_poll_tx_cq(struct mlx5e_cq *cq, int napi_budget)
 
 	netdev_tx_completed_queue(sq->txq, npkts, nbytes);
 
-	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++;
-	}
+	mlx5e_txqsq_wake(sq);
 
 	return (i == MLX5E_TX_CQ_POLL_BUDGET);
 }