From: Maxim Mikityanskiy maximmi@mellanox.com
[ Upstream commit 9cf88808ad6a0f1e958e00abd9a081295fe6da0c ]
After disabling resources necessary for XSK (the XDP program, channels, XSK queues), use synchronize_rcu to wait until the XSK wakeup function finishes, before freeing the resources.
Suspend XSK wakeups during switching channels. If the XDP program is being removed, synchronize_rcu before closing the old channels to allow XSK wakeup to complete.
Signed-off-by: Maxim Mikityanskiy maximmi@mellanox.com Signed-off-by: Daniel Borkmann daniel@iogearbox.net Link: https://lore.kernel.org/bpf/20191217162023.16011-3-maximmi@mellanox.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/mellanox/mlx5/core/en.h | 2 +- .../net/ethernet/mellanox/mlx5/core/en/xdp.h | 22 ++++++++----------- .../mellanox/mlx5/core/en/xsk/setup.c | 1 + .../ethernet/mellanox/mlx5/core/en/xsk/tx.c | 2 +- .../net/ethernet/mellanox/mlx5/core/en_main.c | 19 +--------------- 5 files changed, 13 insertions(+), 33 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en.h b/drivers/net/ethernet/mellanox/mlx5/core/en.h index 2c16add0b642..9c8427698238 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en.h +++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h @@ -760,7 +760,7 @@ enum { MLX5E_STATE_OPENED, MLX5E_STATE_DESTROYING, MLX5E_STATE_XDP_TX_ENABLED, - MLX5E_STATE_XDP_OPEN, + MLX5E_STATE_XDP_ACTIVE, };
struct mlx5e_rqt { diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.h b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.h index 36ac1e3816b9..d7587f40ecae 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.h +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.h @@ -75,12 +75,18 @@ int mlx5e_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames, static inline void mlx5e_xdp_tx_enable(struct mlx5e_priv *priv) { set_bit(MLX5E_STATE_XDP_TX_ENABLED, &priv->state); + + if (priv->channels.params.xdp_prog) + set_bit(MLX5E_STATE_XDP_ACTIVE, &priv->state); }
static inline void mlx5e_xdp_tx_disable(struct mlx5e_priv *priv) { + if (priv->channels.params.xdp_prog) + clear_bit(MLX5E_STATE_XDP_ACTIVE, &priv->state); + clear_bit(MLX5E_STATE_XDP_TX_ENABLED, &priv->state); - /* let other device's napi(s) see our new state */ + /* Let other device's napi(s) and XSK wakeups see our new state. */ synchronize_rcu(); }
@@ -89,19 +95,9 @@ static inline bool mlx5e_xdp_tx_is_enabled(struct mlx5e_priv *priv) return test_bit(MLX5E_STATE_XDP_TX_ENABLED, &priv->state); }
-static inline void mlx5e_xdp_set_open(struct mlx5e_priv *priv) -{ - set_bit(MLX5E_STATE_XDP_OPEN, &priv->state); -} - -static inline void mlx5e_xdp_set_closed(struct mlx5e_priv *priv) -{ - clear_bit(MLX5E_STATE_XDP_OPEN, &priv->state); -} - -static inline bool mlx5e_xdp_is_open(struct mlx5e_priv *priv) +static inline bool mlx5e_xdp_is_active(struct mlx5e_priv *priv) { - return test_bit(MLX5E_STATE_XDP_OPEN, &priv->state); + return test_bit(MLX5E_STATE_XDP_ACTIVE, &priv->state); }
static inline void mlx5e_xmit_xdp_doorbell(struct mlx5e_xdpsq *sq) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/setup.c b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/setup.c index 631af8dee517..c28cbae42331 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/setup.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/setup.c @@ -144,6 +144,7 @@ void mlx5e_close_xsk(struct mlx5e_channel *c) { clear_bit(MLX5E_CHANNEL_STATE_XSK, c->state); napi_synchronize(&c->napi); + synchronize_rcu(); /* Sync with the XSK wakeup. */
mlx5e_close_rq(&c->xskrq); mlx5e_close_cq(&c->xskrq.cq); diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c index 87827477d38c..fe2d596cb361 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c @@ -14,7 +14,7 @@ int mlx5e_xsk_wakeup(struct net_device *dev, u32 qid, u32 flags) struct mlx5e_channel *c; u16 ix;
- if (unlikely(!mlx5e_xdp_is_open(priv))) + if (unlikely(!mlx5e_xdp_is_active(priv))) return -ENETDOWN;
if (unlikely(!mlx5e_qid_get_ch_if_in_group(params, qid, MLX5E_RQ_GROUP_XSK, &ix))) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c index 6abd4ed5b69b..29a5a8c894e3 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c @@ -3002,12 +3002,9 @@ void mlx5e_timestamp_init(struct mlx5e_priv *priv) int mlx5e_open_locked(struct net_device *netdev) { struct mlx5e_priv *priv = netdev_priv(netdev); - bool is_xdp = priv->channels.params.xdp_prog; int err;
set_bit(MLX5E_STATE_OPENED, &priv->state); - if (is_xdp) - mlx5e_xdp_set_open(priv);
err = mlx5e_open_channels(priv, &priv->channels); if (err) @@ -3022,8 +3019,6 @@ int mlx5e_open_locked(struct net_device *netdev) return 0;
err_clear_state_opened_flag: - if (is_xdp) - mlx5e_xdp_set_closed(priv); clear_bit(MLX5E_STATE_OPENED, &priv->state); return err; } @@ -3055,8 +3050,6 @@ int mlx5e_close_locked(struct net_device *netdev) if (!test_bit(MLX5E_STATE_OPENED, &priv->state)) return 0;
- if (priv->channels.params.xdp_prog) - mlx5e_xdp_set_closed(priv); clear_bit(MLX5E_STATE_OPENED, &priv->state);
netif_carrier_off(priv->netdev); @@ -4373,16 +4366,6 @@ static int mlx5e_xdp_allowed(struct mlx5e_priv *priv, struct bpf_prog *prog) return 0; }
-static int mlx5e_xdp_update_state(struct mlx5e_priv *priv) -{ - if (priv->channels.params.xdp_prog) - mlx5e_xdp_set_open(priv); - else - mlx5e_xdp_set_closed(priv); - - return 0; -} - static int mlx5e_xdp_set(struct net_device *netdev, struct bpf_prog *prog) { struct mlx5e_priv *priv = netdev_priv(netdev); @@ -4422,7 +4405,7 @@ static int mlx5e_xdp_set(struct net_device *netdev, struct bpf_prog *prog) mlx5e_set_rq_type(priv->mdev, &new_channels.params); old_prog = priv->channels.params.xdp_prog;
- err = mlx5e_safe_switch_channels(priv, &new_channels, mlx5e_xdp_update_state); + err = mlx5e_safe_switch_channels(priv, &new_channels, NULL); if (err) goto unlock; } else {