From: Aya Levin <ayal@mellanox.com>
Date: Tue, 2 Jul 2019 15:47:29 +0300
Subject: net/mlx5e: Split open/close ICOSQ into stages
Patch-mainline: v5.4-rc1
Git-commit: 9d18b5144a0a850e722e7c3d7b700eb1fba7b7e2
References: jsc#SLE-8464

Align ICOSQ open/close behaviour with RQ and SQ. Split open flow into
open and activate where open handles creation and activate enables the
queue. Do a symmetric thing in close flow: split into close and
deactivate.

Signed-off-by: Aya Levin <ayal@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/mellanox/mlx5/core/en/xsk/setup.c |    2 +
 drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c    |    7 ++++++
 drivers/net/ethernet/mellanox/mlx5/core/en_main.c      |   19 +++++++++++++----
 3 files changed, 24 insertions(+), 4 deletions(-)

--- a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/setup.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/setup.c
@@ -150,6 +150,7 @@ void mlx5e_close_xsk(struct mlx5e_channe
 
 void mlx5e_activate_xsk(struct mlx5e_channel *c)
 {
+	mlx5e_activate_icosq(&c->xskicosq);
 	set_bit(MLX5E_RQ_STATE_ENABLED, &c->xskrq.state);
 	/* TX queue is created active. */
 
@@ -162,6 +163,7 @@ void mlx5e_deactivate_xsk(struct mlx5e_c
 {
 	mlx5e_deactivate_rq(&c->xskrq);
 	/* TX queue is disabled on close. */
+	mlx5e_deactivate_icosq(&c->xskicosq);
 }
 
 static int mlx5e_redirect_xsk_rqt(struct mlx5e_priv *priv, u16 ix, u32 rqn)
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c
@@ -26,6 +26,13 @@ int mlx5e_xsk_async_xmit(struct net_devi
 		return -ENXIO;
 
 	if (!napi_if_scheduled_mark_missed(&c->napi)) {
+		/* To avoid WQE overrun, don't post a NOP if XSKICOSQ is not
+		 * active and not polled by NAPI. Return 0, because the upcoming
+		 * activate will trigger the IRQ for us.
+		 */
+		if (unlikely(!test_bit(MLX5E_SQ_STATE_ENABLED, &c->xskicosq.state)))
+			return 0;
+
 		spin_lock(&c->xskicosq_lock);
 		mlx5e_trigger_irq(&c->xskicosq);
 		spin_unlock(&c->xskicosq_lock);
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -1375,7 +1375,6 @@ int mlx5e_open_icosq(struct mlx5e_channe
 	csp.cqn             = sq->cq.mcq.cqn;
 	csp.wq_ctrl         = &sq->wq_ctrl;
 	csp.min_inline_mode = params->tx_min_inline_mode;
-	set_bit(MLX5E_SQ_STATE_ENABLED, &sq->state);
 	err = mlx5e_create_sq_rdy(c->mdev, param, &csp, &sq->sqn);
 	if (err)
 		goto err_free_icosq;
@@ -1389,12 +1388,22 @@ err_free_icosq:
 	return err;
 }
 
-void mlx5e_close_icosq(struct mlx5e_icosq *sq)
+static void mlx5e_activate_icosq(struct mlx5e_icosq *icosq)
 {
-	struct mlx5e_channel *c = sq->channel;
+	set_bit(MLX5E_SQ_STATE_ENABLED, &icosq->state);
+}
 
-	clear_bit(MLX5E_SQ_STATE_ENABLED, &sq->state);
+static void mlx5e_deactivate_icosq(struct mlx5e_icosq *icosq)
+{
+	struct mlx5e_channel *c = icosq->channel;
+
+	clear_bit(MLX5E_SQ_STATE_ENABLED, &icosq->state);
 	napi_synchronize(&c->napi);
+}
+
+void mlx5e_close_icosq(struct mlx5e_icosq *sq)
+{
+	struct mlx5e_channel *c = sq->channel;
 
 	mlx5e_destroy_sq(c->mdev, sq->sqn);
 	mlx5e_free_icosq(sq);
@@ -1971,6 +1980,7 @@ static void mlx5e_activate_channel(struc
 
 	for (tc = 0; tc < c->num_tc; tc++)
 		mlx5e_activate_txqsq(&c->sq[tc]);
+	mlx5e_activate_icosq(&c->icosq);
 	mlx5e_activate_rq(&c->rq);
 	netif_set_xps_queue(c->netdev, c->xps_cpumask, c->ix);
 
@@ -1986,6 +1996,7 @@ static void mlx5e_deactivate_channel(str
 		mlx5e_deactivate_xsk(c);
 
 	mlx5e_deactivate_rq(&c->rq);
+	mlx5e_deactivate_icosq(&c->icosq);
 	for (tc = 0; tc < c->num_tc; tc++)
 		mlx5e_deactivate_txqsq(&c->sq[tc]);
 }