From 29429f3300a378f7c29583b4c2c2ef29e2190a69 Mon Sep 17 00:00:00 2001 From: Daniel Jurgens Date: Thu, 30 Jun 2016 17:34:44 +0300 Subject: [PATCH] net/mlx5e: Timeout if SQ doesn't flush during close Avoid an infinite loop by timing out waiting for the SQ to flush. Also clean up the TX descriptors if that happens. Fixes: f62b8bb8f2d3 ('net/mlx5: Extend mlx5_core to support ConnectX-4 Ethernet functionality') Signed-off-by: Daniel Jurgens Signed-off-by: Saeed Mahameed Signed-off-by: David S. Miller --- drivers/net/ethernet/mellanox/mlx5/core/en.h | 2 ++ .../net/ethernet/mellanox/mlx5/core/en_main.c | 25 +++++++++++++-- .../net/ethernet/mellanox/mlx5/core/en_tx.c | 32 +++++++++++++++++++ 3 files changed, 56 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en.h b/drivers/net/ethernet/mellanox/mlx5/core/en.h index baa991a23475..c22d8c8a627e 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en.h +++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h @@ -305,6 +305,7 @@ struct mlx5e_sq_dma { enum { MLX5E_SQ_STATE_WAKE_TXQ_ENABLE, MLX5E_SQ_STATE_BF_ENABLE, + MLX5E_SQ_STATE_TX_TIMEOUT, }; struct mlx5e_ico_wqe_info { @@ -589,6 +590,7 @@ void mlx5e_cq_error_event(struct mlx5_core_cq *mcq, enum mlx5_event event); int mlx5e_napi_poll(struct napi_struct *napi, int budget); bool mlx5e_poll_tx_cq(struct mlx5e_cq *cq, int napi_budget); int mlx5e_poll_rx_cq(struct mlx5e_cq *cq, int budget); +void mlx5e_free_tx_descs(struct mlx5e_sq *sq); void mlx5e_handle_rx_cqe(struct mlx5e_rq *rq, struct mlx5_cqe64 *cqe); void mlx5e_handle_rx_cqe_mpwrq(struct mlx5e_rq *rq, struct mlx5_cqe64 *cqe); diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c index cb6defd71fc1..b94c84b4a7c9 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c @@ -39,6 +39,13 @@ #include "eswitch.h" #include "vxlan.h" +enum { + MLX5_EN_QP_FLUSH_TIMEOUT_MS = 5000, + MLX5_EN_QP_FLUSH_MSLEEP_QUANT = 20, + MLX5_EN_QP_FLUSH_MAX_ITER = MLX5_EN_QP_FLUSH_TIMEOUT_MS / + MLX5_EN_QP_FLUSH_MSLEEP_QUANT, +}; + struct mlx5e_rq_param { u32 rqc[MLX5_ST_SZ_DW(rqc)]; struct mlx5_wq_param wq; @@ -782,6 +789,9 @@ static inline void netif_tx_disable_queue(struct netdev_queue *txq) static void mlx5e_close_sq(struct mlx5e_sq *sq) { + int tout = 0; + int err; + if (sq->txq) { clear_bit(MLX5E_SQ_STATE_WAKE_TXQ_ENABLE, &sq->state); /* prevent netif_tx_wake_queue */ @@ -792,15 +802,24 @@ static void mlx5e_close_sq(struct mlx5e_sq *sq) if (mlx5e_sq_has_room_for(sq, 1)) mlx5e_send_nop(sq, true); - mlx5e_modify_sq(sq, MLX5_SQC_STATE_RDY, MLX5_SQC_STATE_ERR); + err = mlx5e_modify_sq(sq, MLX5_SQC_STATE_RDY, + MLX5_SQC_STATE_ERR); + if (err) + set_bit(MLX5E_SQ_STATE_TX_TIMEOUT, &sq->state); } - while (sq->cc != sq->pc) /* wait till sq is empty */ - msleep(20); + /* wait till sq is empty, unless a TX timeout occurred on this SQ */ + while (sq->cc != sq->pc && + !test_bit(MLX5E_SQ_STATE_TX_TIMEOUT, &sq->state)) { + msleep(MLX5_EN_QP_FLUSH_MSLEEP_QUANT); + if (tout++ > MLX5_EN_QP_FLUSH_MAX_ITER) + set_bit(MLX5E_SQ_STATE_TX_TIMEOUT, &sq->state); + } /* avoid destroying sq before mlx5e_poll_tx_cq() is done with it */ napi_synchronize(&sq->channel->napi); + mlx5e_free_tx_descs(sq); mlx5e_disable_sq(sq); mlx5e_destroy_sq(sq); } diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c index 5a750b9cd006..65e3bce8acbb 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c @@ -341,6 +341,35 @@ netdev_tx_t mlx5e_xmit(struct sk_buff *skb, struct net_device *dev) return mlx5e_sq_xmit(sq, skb); } +void mlx5e_free_tx_descs(struct mlx5e_sq *sq) +{ + struct mlx5e_tx_wqe_info *wi; + struct sk_buff *skb; + u16 ci; + int i; + + while (sq->cc != sq->pc) { + ci = sq->cc & sq->wq.sz_m1; + skb = sq->skb[ci]; + wi = &sq->wqe_info[ci]; + + if (!skb) { /* nop */ + sq->cc++; + continue; + } + + for (i = 0; i < wi->num_dma; i++) { + struct mlx5e_sq_dma *dma = + mlx5e_dma_get(sq, sq->dma_fifo_cc++); + + mlx5e_tx_dma_unmap(sq->pdev, dma); + } + + dev_kfree_skb_any(skb); + sq->cc += wi->num_wqebbs; + } +} + bool mlx5e_poll_tx_cq(struct mlx5e_cq *cq, int napi_budget) { struct mlx5e_sq *sq; @@ -352,6 +381,9 @@ bool mlx5e_poll_tx_cq(struct mlx5e_cq *cq, int napi_budget) sq = container_of(cq, struct mlx5e_sq, cq); + if (unlikely(test_bit(MLX5E_SQ_STATE_TX_TIMEOUT, &sq->state))) + return false; + npkts = 0; nbytes = 0;