From 8cbcafcee1910ece54990f9aebae78fcbdb93913 Mon Sep 17 00:00:00 2001 From: Maxim Mikityanskiy Date: Fri, 30 Sep 2022 09:28:49 -0700 Subject: [PATCH] net/mlx5e: xsk: Drop the check for XSK state in mlx5e_xsk_wakeup The MLX5E_CHANNEL_STATE_XSK flag checked in mlx5e_xsk_wakeup indicates that XSK queues are open, but not necessarily activated. This check is not very useful, because: 0. Both XSK setup and netdev state transitions take the same state_lock mutex, so they can't happen at the same time. 1. If the netdev is up, xsk_is_bound can return true only when MLX5E_CHANNEL_STATE_XSK is set on the corresponding channel. mlx5e_xsk_wakeup is only called when xsk_is_bound is true. 2. If the XSK socket is bound, and the netdev is going up or down, mlx5e_xsk_wakeup can take one of two branches, depending on the return value of napi_if_scheduled_mark_missed: 2.1. True means one of two things: either NAPI was enabled at this point, which means MLX5E_CHANNEL_STATE_XSK was also set; or NAPI was disabled, and nothing really happened. 2.2. False means that NAPI was enabled by this point, which also implies MLX5E_CHANNEL_STATE_XSK was set. Additionally, mlx5e_xsk_wakeup contains a following check for MLX5E_SQ_STATE_ENABLED on async_icosq, and this flag implies MLX5E_CHANNEL_STATE_XSK too on XSK channels. As checking this flag doesn't cut any flows, remove the check. Signed-off-by: Maxim Mikityanskiy Reviewed-by: Tariq Toukan Signed-off-by: Saeed Mahameed Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/mellanox/mlx5/core/en/xsk/setup.c | 2 +- drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c | 3 --- 2 files changed, 1 insertion(+), 4 deletions(-) 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 5129b9bf534f..d7dfc7d2c058 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/setup.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/setup.c @@ -154,7 +154,7 @@ err_free_cparam: void mlx5e_close_xsk(struct mlx5e_channel *c) { clear_bit(MLX5E_CHANNEL_STATE_XSK, c->state); - synchronize_net(); /* Sync with the XSK wakeup and with NAPI. */ + synchronize_net(); /* Sync with NAPI. */ 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 1203d7d5f9bd..c856fc3f197e 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c @@ -22,9 +22,6 @@ int mlx5e_xsk_wakeup(struct net_device *dev, u32 qid, u32 flags) c = priv->channels.c[ix]; - if (unlikely(!test_bit(MLX5E_CHANNEL_STATE_XSK, c->state))) - return -EINVAL; - if (!napi_if_scheduled_mark_missed(&c->napi)) { /* To avoid WQE overrun, don't post a NOP if async_icosq is not * active and not polled by NAPI. Return 0, because the upcoming