From a071cb9f25bef32ec309ca9d123022c52175341b Mon Sep 17 00:00:00 2001 From: Tariq Toukan Date: Mon, 3 Jul 2017 10:18:19 +0300 Subject: [PATCH] net/mlx5e: Non-atomic RQ state indicator for UMR WQE in progress The indication for a UMR WQE in progress is needed only within the NAPI context, and hence no races possible and no need for the use of atomic operations. The only place the flag is read outside of NAPI context is in closure flow, after RQ is disabled flag is no more accessed in NAPI. Use a boolean instead of a bit in ring state, so that its non-atomic set operations do not race with the atomic sets of the other bits. Signed-off-by: Tariq Toukan Signed-off-by: Saeed Mahameed --- drivers/net/ethernet/mellanox/mlx5/core/en.h | 2 +- drivers/net/ethernet/mellanox/mlx5/core/en_main.c | 3 ++- drivers/net/ethernet/mellanox/mlx5/core/en_rx.c | 10 +++++----- 3 files changed, 8 insertions(+), 7 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en.h b/drivers/net/ethernet/mellanox/mlx5/core/en.h index 0c4f1f3..bce2080 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en.h +++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h @@ -291,7 +291,6 @@ struct mlx5e_tstamp { enum { MLX5E_RQ_STATE_ENABLED, - MLX5E_RQ_STATE_UMR_WQE_IN_PROGRESS, MLX5E_RQ_STATE_AM, }; @@ -539,6 +538,7 @@ struct mlx5e_rq { void *mtt_no_align; u16 num_strides; u8 log_stride_sz; + bool umr_in_progress; } mpwqe; }; struct { diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c index 411fb68..2767a3e 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c @@ -886,7 +886,8 @@ static void mlx5e_free_rx_descs(struct mlx5e_rq *rq) u16 wqe_ix; /* UMR WQE (if in progress) is always at wq->head */ - if (test_bit(MLX5E_RQ_STATE_UMR_WQE_IN_PROGRESS, &rq->state)) + if (rq->wq_type == MLX5_WQ_TYPE_LINKED_LIST_STRIDING_RQ && + rq->mpwqe.umr_in_progress) mlx5e_free_rx_mpwqe(rq, &rq->mpwqe.info[wq->head]); while (!mlx5_wq_ll_is_empty(wq)) { diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c index a5522c3..11dba99 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c @@ -422,7 +422,7 @@ void mlx5e_post_rx_mpwqe(struct mlx5e_rq *rq) struct mlx5_wq_ll *wq = &rq->wq; struct mlx5e_rx_wqe *wqe = mlx5_wq_ll_get_wqe(wq, wq->head); - clear_bit(MLX5E_RQ_STATE_UMR_WQE_IN_PROGRESS, &rq->state); + rq->mpwqe.umr_in_progress = false; if (unlikely(!MLX5E_TEST_BIT(rq->state, MLX5E_RQ_STATE_ENABLED))) { mlx5e_free_rx_mpwqe(rq, &rq->mpwqe.info[wq->head]); @@ -441,10 +441,13 @@ int mlx5e_alloc_rx_mpwqe(struct mlx5e_rq *rq, struct mlx5e_rx_wqe *wqe, u16 ix) { int err; + if (rq->mpwqe.umr_in_progress) + return -EBUSY; + err = mlx5e_alloc_rx_umr_mpwqe(rq, ix); if (unlikely(err)) return err; - set_bit(MLX5E_RQ_STATE_UMR_WQE_IN_PROGRESS, &rq->state); + rq->mpwqe.umr_in_progress = true; mlx5e_post_umr_wqe(rq, ix); return -EBUSY; } @@ -467,9 +470,6 @@ bool mlx5e_post_rx_wqes(struct mlx5e_rq *rq) if (mlx5_wq_ll_is_full(wq)) return false; - if (test_bit(MLX5E_RQ_STATE_UMR_WQE_IN_PROGRESS, &rq->state)) - return true; - do { struct mlx5e_rx_wqe *wqe = mlx5_wq_ll_get_wqe(wq, wq->head); -- 2.7.4