From a1eaba4c5c29b6b5196b2237ce3a8d7d97622b2f Mon Sep 17 00:00:00 2001 From: Tariq Toukan Date: Mon, 3 Jul 2017 11:27:20 +0300 Subject: [PATCH] net/mlx5e: Non-atomic indicator for ring enabled state Rings enabled state change occurs in control path only, and is always followed by a napi_sychronize(), so that following NAPIs read the new value. This read does not need to be atomic. The RQ auto-moderation bit is not set/cleared in data-path. No need for atomic read, a regular read operation is sufficient. In RQ creation time as well, there's no multiple threads trying to access it yet, hence a regular read can be used. 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 | 2 +- drivers/net/ethernet/mellanox/mlx5/core/en_rx.c | 8 ++++---- drivers/net/ethernet/mellanox/mlx5/core/en_tx.c | 2 +- drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c | 4 ++-- 5 files changed, 10 insertions(+), 8 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en.h b/drivers/net/ethernet/mellanox/mlx5/core/en.h index ce8b4f6..0c4f1f3 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en.h +++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h @@ -295,6 +295,8 @@ enum { MLX5E_RQ_STATE_AM, }; +#define MLX5E_TEST_BIT(state, nr) (state & BIT(nr)) + struct mlx5e_cq { /* data path - accessed per cqe */ struct mlx5_cqwq wq; diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c index 5aa4681..411fb68 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c @@ -929,7 +929,7 @@ static int mlx5e_open_rq(struct mlx5e_channel *c, goto err_destroy_rq; if (params->rx_am_enabled) - set_bit(MLX5E_RQ_STATE_AM, &c->rq.state); + c->rq.state |= BIT(MLX5E_RQ_STATE_AM); return 0; diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c index 9d9c13a..a5522c3 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c @@ -424,7 +424,7 @@ void mlx5e_post_rx_mpwqe(struct mlx5e_rq *rq) clear_bit(MLX5E_RQ_STATE_UMR_WQE_IN_PROGRESS, &rq->state); - if (unlikely(!test_bit(MLX5E_RQ_STATE_ENABLED, &rq->state))) { + if (unlikely(!MLX5E_TEST_BIT(rq->state, MLX5E_RQ_STATE_ENABLED))) { mlx5e_free_rx_mpwqe(rq, &rq->mpwqe.info[wq->head]); return; } @@ -461,7 +461,7 @@ bool mlx5e_post_rx_wqes(struct mlx5e_rq *rq) struct mlx5_wq_ll *wq = &rq->wq; int err; - if (unlikely(!test_bit(MLX5E_RQ_STATE_ENABLED, &rq->state))) + if (unlikely(!MLX5E_TEST_BIT(rq->state, MLX5E_RQ_STATE_ENABLED))) return false; if (mlx5_wq_ll_is_full(wq)) @@ -983,7 +983,7 @@ int mlx5e_poll_rx_cq(struct mlx5e_cq *cq, int budget) struct mlx5_cqe64 *cqe; int work_done = 0; - if (unlikely(!test_bit(MLX5E_RQ_STATE_ENABLED, &rq->state))) + if (unlikely(!MLX5E_TEST_BIT(rq->state, MLX5E_RQ_STATE_ENABLED))) return 0; if (cq->decmprs_left) @@ -1031,7 +1031,7 @@ bool mlx5e_poll_xdpsq_cq(struct mlx5e_cq *cq) sq = container_of(cq, struct mlx5e_xdpsq, cq); - if (unlikely(!test_bit(MLX5E_SQ_STATE_ENABLED, &sq->state))) + if (unlikely(!MLX5E_TEST_BIT(sq->state, MLX5E_SQ_STATE_ENABLED))) return false; cqe = mlx5_cqwq_get_cqe(&cq->wq); diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c index 80d2121..fee43e4 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c @@ -403,7 +403,7 @@ bool mlx5e_poll_tx_cq(struct mlx5e_cq *cq, int napi_budget) sq = container_of(cq, struct mlx5e_txqsq, cq); - if (unlikely(!test_bit(MLX5E_SQ_STATE_ENABLED, &sq->state))) + if (unlikely(!MLX5E_TEST_BIT(sq->state, MLX5E_SQ_STATE_ENABLED))) return false; cqe = mlx5_cqwq_get_cqe(&cq->wq); diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c index 92db28a..7311b93 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c @@ -69,7 +69,7 @@ static void mlx5e_poll_ico_cq(struct mlx5e_cq *cq) struct mlx5_cqe64 *cqe; u16 sqcc; - if (unlikely(!test_bit(MLX5E_SQ_STATE_ENABLED, &sq->state))) + if (unlikely(!MLX5E_TEST_BIT(sq->state, MLX5E_SQ_STATE_ENABLED))) return; cqe = mlx5_cqwq_get_cqe(&cq->wq); @@ -129,7 +129,7 @@ int mlx5e_napi_poll(struct napi_struct *napi, int budget) for (i = 0; i < c->num_tc; i++) mlx5e_cq_arm(&c->sq[i].cq); - if (test_bit(MLX5E_RQ_STATE_AM, &c->rq.state)) + if (MLX5E_TEST_BIT(c->rq.state, MLX5E_RQ_STATE_AM)) mlx5e_rx_am(&c->rq); mlx5e_cq_arm(&c->rq.cq); -- 2.7.4