From ed5f9cf06b20f74c1098d6d62313e3e9af217fcb Mon Sep 17 00:00:00 2001 From: Maxim Mikityanskiy Date: Tue, 25 Jan 2022 12:52:56 +0200 Subject: net/mlx5e: Use READ_ONCE/WRITE_ONCE for DCBX trust state trust_state can be written while mlx5e_select_queue() is reading it. To avoid inconsistencies, use READ_ONCE and WRITE_ONCE for access and updates, and touch the variable only once per operation. Signed-off-by: Maxim Mikityanskiy Reviewed-by: Tariq Toukan Signed-off-by: Saeed Mahameed --- drivers/net/ethernet/mellanox/mlx5/core/en/selq.c | 2 +- drivers/net/ethernet/mellanox/mlx5/core/en_dcbnl.c | 12 +++++++----- 2 files changed, 8 insertions(+), 6 deletions(-) (limited to 'drivers') diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/selq.c b/drivers/net/ethernet/mellanox/mlx5/core/en/selq.c index aab2046da45b..b8f1a955944d 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/selq.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/selq.c @@ -113,7 +113,7 @@ static int mlx5e_get_dscp_up(struct mlx5e_priv *priv, struct sk_buff *skb) static int mlx5e_get_up(struct mlx5e_priv *priv, struct sk_buff *skb) { #ifdef CONFIG_MLX5_CORE_EN_DCB - if (priv->dcbx_dp.trust_state == MLX5_QPTS_TRUST_DSCP) + if (READ_ONCE(priv->dcbx_dp.trust_state) == MLX5_QPTS_TRUST_DSCP) return mlx5e_get_dscp_up(priv, skb); #endif if (skb_vlan_tag_present(skb)) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_dcbnl.c b/drivers/net/ethernet/mellanox/mlx5/core/en_dcbnl.c index a4c8d8d00d5a..d659fe07d464 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_dcbnl.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_dcbnl.c @@ -1142,7 +1142,7 @@ static int mlx5e_update_trust_state_hw(struct mlx5e_priv *priv, void *context) err = mlx5_set_trust_state(priv->mdev, *trust_state); if (err) return err; - priv->dcbx_dp.trust_state = *trust_state; + WRITE_ONCE(priv->dcbx_dp.trust_state, *trust_state); return 0; } @@ -1187,16 +1187,18 @@ static int mlx5e_set_dscp2prio(struct mlx5e_priv *priv, u8 dscp, u8 prio) static int mlx5e_trust_initialize(struct mlx5e_priv *priv) { struct mlx5_core_dev *mdev = priv->mdev; + u8 trust_state; int err; - priv->dcbx_dp.trust_state = MLX5_QPTS_TRUST_PCP; - - if (!MLX5_DSCP_SUPPORTED(mdev)) + if (!MLX5_DSCP_SUPPORTED(mdev)) { + WRITE_ONCE(priv->dcbx_dp.trust_state, MLX5_QPTS_TRUST_PCP); return 0; + } - err = mlx5_query_trust_state(priv->mdev, &priv->dcbx_dp.trust_state); + err = mlx5_query_trust_state(priv->mdev, &trust_state); if (err) return err; + WRITE_ONCE(priv->dcbx_dp.trust_state, trust_state); mlx5e_params_calc_trust_tx_min_inline_mode(priv->mdev, &priv->channels.params, priv->dcbx_dp.trust_state); -- cgit v1.2.3