diff options
| author | Tariq Toukan <tariqt@mellanox.com> | 2017-06-15 14:35:40 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-06-15 22:53:23 -0400 |
| commit | 4c07c132408a685d31bb6e638aef4d245e30703a (patch) | |
| tree | 6c8379e98405b231cf3e89fb732f938ba58d074e /drivers | |
| parent | 9573e0d39ff8d7d1e0bcc10e23d18b9cbc4ca14e (diff) | |
| download | linux-4c07c132408a685d31bb6e638aef4d245e30703a.tar.bz2 | |
net/mlx4_en: Refactor mlx4_en_free_tx_desc
Some code re-ordering, functionally equivalent.
- The !tx_info->inl check is evaluated anyway in both flows
(common case/end case). Run it first, this might finish
the flows earlier.
- dma_unmap calls are identical in both flows, get it out
of the if block into the common area.
Performance tests:
Tested on ConnectX3Pro, Intel(R) Xeon(R) CPU E5-2680 v3 @ 2.50GHz
Gain is too small to be measurable, no degradation sensed.
Results are similar for IPv4 and IPv6.
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Reviewed-by: Saeed Mahameed <saeedm@mellanox.com>
Cc: kernel-team@fb.com
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/net/ethernet/mellanox/mlx4/en_tx.c | 45 |
1 files changed, 16 insertions, 29 deletions
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_tx.c b/drivers/net/ethernet/mellanox/mlx4/en_tx.c index efc4411b1e44..7d69d939ee2d 100644 --- a/drivers/net/ethernet/mellanox/mlx4/en_tx.c +++ b/drivers/net/ethernet/mellanox/mlx4/en_tx.c @@ -289,20 +289,20 @@ u32 mlx4_en_free_tx_desc(struct mlx4_en_priv *priv, skb_tstamp_tx(skb, &hwts); } - /* Optimize the common case when there are no wraparounds */ - if (likely((void *)tx_desc + - (tx_info->nr_txbb << LOG_TXBB_SIZE) <= end)) { - if (!tx_info->inl) { - if (tx_info->linear) - dma_unmap_single(priv->ddev, - tx_info->map0_dma, - tx_info->map0_byte_count, - PCI_DMA_TODEVICE); - else - dma_unmap_page(priv->ddev, - tx_info->map0_dma, - tx_info->map0_byte_count, - PCI_DMA_TODEVICE); + if (!tx_info->inl) { + if (tx_info->linear) + dma_unmap_single(priv->ddev, + tx_info->map0_dma, + tx_info->map0_byte_count, + PCI_DMA_TODEVICE); + else + dma_unmap_page(priv->ddev, + tx_info->map0_dma, + tx_info->map0_byte_count, + PCI_DMA_TODEVICE); + /* Optimize the common case when there are no wraparounds */ + if (likely((void *)tx_desc + + (tx_info->nr_txbb << LOG_TXBB_SIZE) <= end)) { for (i = 1; i < nr_maps; i++) { data++; dma_unmap_page(priv->ddev, @@ -310,23 +310,10 @@ u32 mlx4_en_free_tx_desc(struct mlx4_en_priv *priv, be32_to_cpu(data->byte_count), PCI_DMA_TODEVICE); } - } - } else { - if (!tx_info->inl) { - if ((void *) data >= end) { + } else { + if ((void *)data >= end) data = ring->buf + ((void *)data - end); - } - if (tx_info->linear) - dma_unmap_single(priv->ddev, - tx_info->map0_dma, - tx_info->map0_byte_count, - PCI_DMA_TODEVICE); - else - dma_unmap_page(priv->ddev, - tx_info->map0_dma, - tx_info->map0_byte_count, - PCI_DMA_TODEVICE); for (i = 1; i < nr_maps; i++) { data++; /* Check for wraparound before unmapping */ |