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

BugLink: https://bugs.launchpad.net/bugs/2028979

commit 7aa5038 upstream.

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: 1880bc4 ("net/mlx5e: Add TX port timestamp support")
Signed-off-by: Rahul Rameshbabu <rrameshbabu@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

Author: Binary-Eater

drivers/net/ethernet/mellanox/mlx5/core/en/ptp.c

@@ -175,6 +175,8 @@ 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;
 }
 

drivers/net/ethernet/mellanox/mlx5/core/en/txrx.h

@@ -177,6 +177,8 @@ static inline u16 mlx5e_txqsq_get_next_pi(struct mlx5e_txqsq *sq, u16 size)
 	return pi;
 }
 
+void mlx5e_txqsq_wake(struct mlx5e_txqsq *sq);
+
 static inline u16 mlx5e_shampo_get_cqe_header_index(struct mlx5e_rq *rq, struct mlx5_cqe64 *cqe)
 {
 	return be16_to_cpu(cqe->shampo.header_entry_index) & (rq->mpwqe.shampo->hd_per_wq - 1);

drivers/net/ethernet/mellanox/mlx5/core/en_tx.c

@@ -777,6 +777,17 @@ 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;
@@ -876,13 +887,7 @@ 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);
 }