Commit ff36c447 authored by Jakub Kicinski's avatar Jakub Kicinski
Browse files

Merge branch 'mlx4-better-big-tcp-support' 

Eric Dumazet says:

====================
mlx4: better BIG-TCP support

mlx4 uses a bounce buffer in TX whenever the tx descriptors
wrap around the right edge of the ring.

Size of this bounce buffer was hard coded and can be
increased if/when needed.
====================

Link: https://lore.kernel.org/r/20221207141237.2575012-1-edumazet@google.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parents ddda6326 0e706f79

drivers/net/ethernet/mellanox/mlx4/en_tx.c

+10 −8
Original line number Diff line number Diff line
@@ -65,7 +65,7 @@ int mlx4_en_create_tx_ring(struct mlx4_en_priv *priv, 
	ring->size = size;

	ring->size_mask = size - 1;

	ring->sp_stride = stride;

	ring->full_size = ring->size - HEADROOM - MAX_DESC_TXBBS;

	ring->full_size = ring->size - HEADROOM - MLX4_MAX_DESC_TXBBS;



	tmp = size * sizeof(struct mlx4_en_tx_info);

	ring->tx_info = kvmalloc_node(tmp, GFP_KERNEL, node);
@@ -77,9 +77,11 @@ int mlx4_en_create_tx_ring(struct mlx4_en_priv *priv, 
	en_dbg(DRV, priv, "Allocated tx_info ring at addr:%p size:%d\n",

		 ring->tx_info, tmp);



	ring->bounce_buf = kmalloc_node(MAX_DESC_SIZE, GFP_KERNEL, node);

	ring->bounce_buf = kmalloc_node(MLX4_TX_BOUNCE_BUFFER_SIZE,

					GFP_KERNEL, node);

	if (!ring->bounce_buf) {

		ring->bounce_buf = kmalloc(MAX_DESC_SIZE, GFP_KERNEL);

		ring->bounce_buf = kmalloc(MLX4_TX_BOUNCE_BUFFER_SIZE,

					   GFP_KERNEL);

		if (!ring->bounce_buf) {

			err = -ENOMEM;

			goto err_info;
@@ -909,11 +911,6 @@ netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev) 
	/* Align descriptor to TXBB size */

	desc_size = ALIGN(real_size, TXBB_SIZE);

	nr_txbb = desc_size >> LOG_TXBB_SIZE;

	if (unlikely(nr_txbb > MAX_DESC_TXBBS)) {

		if (netif_msg_tx_err(priv))

			en_warn(priv, "Oversized header or SG list\n");

		goto tx_drop_count;

	}



	bf_ok = ring->bf_enabled;

	if (skb_vlan_tag_present(skb)) {
@@ -941,6 +938,11 @@ netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev) 
	if (likely(index + nr_txbb <= ring->size))

		tx_desc = ring->buf + (index << LOG_TXBB_SIZE);

	else {

		if (unlikely(nr_txbb > MLX4_MAX_DESC_TXBBS)) {

			if (netif_msg_tx_err(priv))

				en_warn(priv, "Oversized header or SG list\n");

			goto tx_drop_count;

		}

		tx_desc = (struct mlx4_en_tx_desc *) ring->bounce_buf;

		bounce = true;

		bf_ok = false;

drivers/net/ethernet/mellanox/mlx4/mlx4_en.h

+13 −5
Original line number Diff line number Diff line
@@ -89,9 +89,19 @@ 
#define MLX4_EN_FILTER_HASH_SHIFT 4

#define MLX4_EN_FILTER_EXPIRY_QUOTA 60



/* Typical TSO descriptor with 16 gather entries is 352 bytes... */

#define MAX_DESC_SIZE		512

#define MAX_DESC_TXBBS		(MAX_DESC_SIZE / TXBB_SIZE)

#define CTRL_SIZE	sizeof(struct mlx4_wqe_ctrl_seg)

#define DS_SIZE		sizeof(struct mlx4_wqe_data_seg)



/* Maximal size of the bounce buffer:

 * 256 bytes for LSO headers.

 * CTRL_SIZE for control desc.

 * DS_SIZE if skb->head contains some payload.

 * MAX_SKB_FRAGS frags.

 */

#define MLX4_TX_BOUNCE_BUFFER_SIZE \

	ALIGN(256 + CTRL_SIZE + DS_SIZE + MAX_SKB_FRAGS * DS_SIZE, TXBB_SIZE)



#define MLX4_MAX_DESC_TXBBS	   (MLX4_TX_BOUNCE_BUFFER_SIZE / TXBB_SIZE)



/*

 * OS related constants and tunables
@@ -217,9 +227,7 @@ struct mlx4_en_tx_info { 




#define MLX4_EN_BIT_DESC_OWN	0x80000000

#define CTRL_SIZE	sizeof(struct mlx4_wqe_ctrl_seg)

#define MLX4_EN_MEMTYPE_PAD	0x100

#define DS_SIZE		sizeof(struct mlx4_wqe_data_seg)





struct mlx4_en_tx_desc {