From 885eb0a516e4d686849b91c5a1ba25c70b7a6540 Mon Sep 17 00:00:00 2001 From: Jesper Dangaard Brouer Date: Fri, 11 Mar 2016 09:43:58 +0100 Subject: [PATCH 1/3] net: adjust napi_consume_skb to handle non-NAPI callers Some drivers reuse/share code paths that free SKBs between NAPI and non-NAPI calls. Adjust napi_consume_skb to handle this use-case. Before, calls from netpoll (w/ IRQs disabled) was handled and indicated with a budget zero indication. Use the same zero indication to handle calls not originating from NAPI/softirq. Simply handled by using dev_consume_skb_any(). This adds an extra branch+call for the netpoll case (checking in_irq() + irqs_disabled()), but that is okay as this is a slowpath. Suggested-by: Alexander Duyck Signed-off-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller --- net/core/skbuff.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 51d768e7bc90b..f044f970f1a63 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -801,9 +801,9 @@ void napi_consume_skb(struct sk_buff *skb, int budget) if (unlikely(!skb)) return; - /* if budget is 0 assume netpoll w/ IRQs disabled */ + /* Zero budget indicate non-NAPI context called us, like netpoll */ if (unlikely(!budget)) { - dev_consume_skb_irq(skb); + dev_consume_skb_any(skb); return; } From b4a53379a0c19df784e30b1f35af5841f2b74f30 Mon Sep 17 00:00:00 2001 From: Jesper Dangaard Brouer Date: Fri, 11 Mar 2016 09:44:08 +0100 Subject: [PATCH 2/3] mlx4: use napi_consume_skb API to get bulk free operations Bulk free of SKBs happen transparently by the API call napi_consume_skb(). The napi budget parameter is usually needed by napi_consume_skb() to detect if called from netpoll. In this patch it has an extra meaning. For mlx4 driver, the mlx4_en_stop_port() call is done outside NAPI/softirq context, and cleanup the entire TX ring via mlx4_en_free_tx_buf(). The code mlx4_en_free_tx_desc() for freeing SKBs are shared with NAPI calls. To handle this shared use the zero budget indication is reused, and handled appropriately in napi_consume_skb(). To reflect this, variable is called napi_mode for the function call that needed this distinction. Signed-off-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller --- drivers/net/ethernet/mellanox/mlx4/en_tx.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx4/en_tx.c b/drivers/net/ethernet/mellanox/mlx4/en_tx.c index e0946ab22010f..c0d7b72962363 100644 --- a/drivers/net/ethernet/mellanox/mlx4/en_tx.c +++ b/drivers/net/ethernet/mellanox/mlx4/en_tx.c @@ -276,7 +276,8 @@ static void mlx4_en_stamp_wqe(struct mlx4_en_priv *priv, static u32 mlx4_en_free_tx_desc(struct mlx4_en_priv *priv, struct mlx4_en_tx_ring *ring, - int index, u8 owner, u64 timestamp) + int index, u8 owner, u64 timestamp, + int napi_mode) { struct mlx4_en_tx_info *tx_info = &ring->tx_info[index]; struct mlx4_en_tx_desc *tx_desc = ring->buf + index * TXBB_SIZE; @@ -347,7 +348,8 @@ static u32 mlx4_en_free_tx_desc(struct mlx4_en_priv *priv, } } } - dev_consume_skb_any(skb); + napi_consume_skb(skb, napi_mode); + return tx_info->nr_txbb; } @@ -371,7 +373,8 @@ int mlx4_en_free_tx_buf(struct net_device *dev, struct mlx4_en_tx_ring *ring) while (ring->cons != ring->prod) { ring->last_nr_txbb = mlx4_en_free_tx_desc(priv, ring, ring->cons & ring->size_mask, - !!(ring->cons & ring->size), 0); + !!(ring->cons & ring->size), 0, + 0 /* Non-NAPI caller */); ring->cons += ring->last_nr_txbb; cnt++; } @@ -385,7 +388,7 @@ int mlx4_en_free_tx_buf(struct net_device *dev, struct mlx4_en_tx_ring *ring) } static bool mlx4_en_process_tx_cq(struct net_device *dev, - struct mlx4_en_cq *cq) + struct mlx4_en_cq *cq, int napi_budget) { struct mlx4_en_priv *priv = netdev_priv(dev); struct mlx4_cq *mcq = &cq->mcq; @@ -451,7 +454,7 @@ static bool mlx4_en_process_tx_cq(struct net_device *dev, last_nr_txbb = mlx4_en_free_tx_desc( priv, ring, ring_index, !!((ring_cons + txbbs_skipped) & - ring->size), timestamp); + ring->size), timestamp, napi_budget); mlx4_en_stamp_wqe(priv, ring, stamp_index, !!((ring_cons + txbbs_stamp) & @@ -511,7 +514,7 @@ int mlx4_en_poll_tx_cq(struct napi_struct *napi, int budget) struct mlx4_en_priv *priv = netdev_priv(dev); int clean_complete; - clean_complete = mlx4_en_process_tx_cq(dev, cq); + clean_complete = mlx4_en_process_tx_cq(dev, cq, budget); if (!clean_complete) return budget; From 8ec736e556e3340b4b4295c7567b0766d6629702 Mon Sep 17 00:00:00 2001 From: Jesper Dangaard Brouer Date: Fri, 11 Mar 2016 09:44:17 +0100 Subject: [PATCH 3/3] mlx5: use napi_consume_skb API to get bulk free operations Bulk free of SKBs happen transparently by the API call napi_consume_skb(). The napi budget parameter is needed by napi_consume_skb() to detect if called from netpoll. Signed-off-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller --- drivers/net/ethernet/mellanox/mlx5/core/en.h | 2 +- drivers/net/ethernet/mellanox/mlx5/core/en_tx.c | 4 ++-- drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c | 2 +- 3 files changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en.h b/drivers/net/ethernet/mellanox/mlx5/core/en.h index 0f76d321030ff..0cb4a093958b5 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en.h +++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h @@ -629,7 +629,7 @@ netdev_tx_t mlx5e_xmit(struct sk_buff *skb, struct net_device *dev); void mlx5e_completion_event(struct mlx5_core_cq *mcq); 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); +bool mlx5e_poll_tx_cq(struct mlx5e_cq *cq, int napi_budget); int mlx5e_poll_rx_cq(struct mlx5e_cq *cq, int budget); bool mlx5e_post_rx_wqes(struct mlx5e_rq *rq); struct mlx5_cqe64 *mlx5e_get_cqe(struct mlx5e_cq *cq); diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c index 94a14f85f70d8..1ffc7cb6f78c4 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c @@ -339,7 +339,7 @@ netdev_tx_t mlx5e_xmit(struct sk_buff *skb, struct net_device *dev) return mlx5e_sq_xmit(sq, skb); } -bool mlx5e_poll_tx_cq(struct mlx5e_cq *cq) +bool mlx5e_poll_tx_cq(struct mlx5e_cq *cq, int napi_budget) { struct mlx5e_sq *sq; u32 dma_fifo_cc; @@ -411,7 +411,7 @@ bool mlx5e_poll_tx_cq(struct mlx5e_cq *cq) npkts++; nbytes += wi->num_bytes; sqcc += wi->num_wqebbs; - dev_kfree_skb(skb); + napi_consume_skb(skb, napi_budget); } while (!last_wqe); } diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c index 66d51a77609e8..9bb4395aceeb4 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c @@ -60,7 +60,7 @@ int mlx5e_napi_poll(struct napi_struct *napi, int budget) clear_bit(MLX5E_CHANNEL_NAPI_SCHED, &c->flags); for (i = 0; i < c->num_tc; i++) - busy |= mlx5e_poll_tx_cq(&c->sq[i].cq); + busy |= mlx5e_poll_tx_cq(&c->sq[i].cq, budget); work_done = mlx5e_poll_rx_cq(&c->rq.cq, budget); busy |= work_done == budget;