[PATCH 5.10 121/142] net/mlx5e: Correctly handle changing the number of queues when the interface is down

Greg Kroah-Hartman
2021-02-02T14:02:31Z

From: Maxim Mikityanskiy <maximmi@mellanox.com>

[ Upstream commit 57ac4a31c48377a3e675b2a731ceacbefefcd34d ]

This commit addresses two issues related to changing the number of
queues when the channels are closed:

1. Missing call to mlx5e_num_channels_changed to update
real_num_tx_queues when the number of TCs is changed.

2. When mlx5e_num_channels_changed returns an error, the channel
parameters must be reverted.

Two Fixes: tags correspond to the first commits where these two issues
were introduced.

Fixes: 3909a12e7913 ("net/mlx5e: Fix configuration of XPS cpumasks and netdev queues in corner cases")
Fixes: fa3748775b92 ("net/mlx5e: Handle errors from netif_set_real_num_{tx,rx}_queues")
Signed-off-by: Maxim Mikityanskiy <maximmi@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c | 8 +++++++-
drivers/net/ethernet/mellanox/mlx5/core/en_main.c | 7 +++++++
2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
index f01395a9fd8df..e596f050c4316 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
@@ -444,12 +444,18 @@ int mlx5e_ethtool_set_channels(struct mlx5e_priv *priv,
goto out;
}

- new_channels.params = priv->channels.params;
+ new_channels.params = *cur_params;
new_channels.params.num_channels = count;

if (!test_bit(MLX5E_STATE_OPENED, &priv->state)) {
+ struct mlx5e_params old_params;
+
+ old_params = *cur_params;
*cur_params = new_channels.params;
err = mlx5e_num_channels_changed(priv);
+ if (err)
+ *cur_params = old_params;
+
goto out;
}

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index ba6c75618a710..000dacaa3333c 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -3580,7 +3580,14 @@ static int mlx5e_setup_tc_mqprio(struct mlx5e_priv *priv,
new_channels.params.num_tc = tc ? tc : 1;

if (!test_bit(MLX5E_STATE_OPENED, &priv->state)) {
+ struct mlx5e_params old_params;
+
+ old_params = priv->channels.params;
priv->channels.params = new_channels.params;
+ err = mlx5e_num_channels_changed(priv);
+ if (err)
+ priv->channels.params = old_params;
+
goto out;
}

--
2.27.0