diff options
| author | Yevgeny Petrilin <yevgenyp@mellanox.co.il> | 2012-03-06 04:03:34 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2012-03-06 15:19:17 -0500 |
| commit | ebf8c9aa032f03343b91c91951b0705021b02eb0 (patch) | |
| tree | 821ec45a0319a6592603a66048700bac3b0f15bc /drivers/net/ethernet/mellanox/mlx4/en_rx.c | |
| parent | 6975f4ce5a44e337514283e84761adaf2849aa26 (diff) | |
net/mlx4_en: Saving mem access on data path
Localized the pdev->dev, and using dma_map instead of pci_map
There are multiple map/unmap operations on data path,
optimizing those by saving redundant pointer access.
Those places were identified as hot-spots when running kernel profiling
during some benchmarks.
The fixes had most impact when testing packet rate with small packets,
reducing several % from CPU load, and in some case being the difference
between reaching wire speed or being CPU bound.
Signed-off-by: Yevgeny Petrilin <yevgenyp@mellanox.co.il>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/ethernet/mellanox/mlx4/en_rx.c')
| -rw-r--r-- | drivers/net/ethernet/mellanox/mlx4/en_rx.c | 14 |
1 files changed, 5 insertions, 9 deletions
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c index d703ef2c9c9..c881712b749 100644 --- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c +++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c @@ -48,7 +48,6 @@ static int mlx4_en_alloc_frag(struct mlx4_en_priv *priv, struct mlx4_en_rx_alloc *ring_alloc, int i) { - struct mlx4_en_dev *mdev = priv->mdev; struct mlx4_en_frag_info *frag_info = &priv->frag_info[i]; struct mlx4_en_rx_alloc *page_alloc = &ring_alloc[i]; struct page *page; @@ -72,7 +71,7 @@ static int mlx4_en_alloc_frag(struct mlx4_en_priv *priv, skb_frags[i].offset = page_alloc->offset; page_alloc->offset += frag_info->frag_stride; } - dma = pci_map_single(mdev->pdev, page_address(skb_frags[i].page) + + dma = dma_map_single(priv->ddev, page_address(skb_frags[i].page) + skb_frags[i].offset, frag_info->frag_size, PCI_DMA_FROMDEVICE); rx_desc->data[i].addr = cpu_to_be64(dma); @@ -186,7 +185,6 @@ static void mlx4_en_free_rx_desc(struct mlx4_en_priv *priv, struct mlx4_en_rx_ring *ring, int index) { - struct mlx4_en_dev *mdev = priv->mdev; struct page_frag *skb_frags; struct mlx4_en_rx_desc *rx_desc = ring->buf + (index << ring->log_stride); dma_addr_t dma; @@ -198,7 +196,7 @@ static void mlx4_en_free_rx_desc(struct mlx4_en_priv *priv, dma = be64_to_cpu(rx_desc->data[nr].addr); en_dbg(DRV, priv, "Unmapping buffer at dma:0x%llx\n", (u64) dma); - pci_unmap_single(mdev->pdev, dma, skb_frags[nr].size, + dma_unmap_single(priv->ddev, dma, skb_frags[nr].size, PCI_DMA_FROMDEVICE); put_page(skb_frags[nr].page); } @@ -412,7 +410,6 @@ static int mlx4_en_complete_rx_desc(struct mlx4_en_priv *priv, int length) { struct skb_frag_struct *skb_frags_rx = skb_shinfo(skb)->frags; - struct mlx4_en_dev *mdev = priv->mdev; struct mlx4_en_frag_info *frag_info; int nr; dma_addr_t dma; @@ -435,7 +432,7 @@ static int mlx4_en_complete_rx_desc(struct mlx4_en_priv *priv, goto fail; /* Unmap buffer */ - pci_unmap_single(mdev->pdev, dma, skb_frag_size(&skb_frags_rx[nr]), + dma_unmap_single(priv->ddev, dma, skb_frag_size(&skb_frags_rx[nr]), PCI_DMA_FROMDEVICE); } /* Adjust size of last fragment to match actual length */ @@ -461,7 +458,6 @@ static struct sk_buff *mlx4_en_rx_skb(struct mlx4_en_priv *priv, struct mlx4_en_rx_alloc *page_alloc, unsigned int length) { - struct mlx4_en_dev *mdev = priv->mdev; struct sk_buff *skb; void *va; int used_frags; @@ -483,10 +479,10 @@ static struct sk_buff *mlx4_en_rx_skb(struct mlx4_en_priv *priv, /* We are copying all relevant data to the skb - temporarily * synch buffers for the copy */ dma = be64_to_cpu(rx_desc->data[0].addr); - dma_sync_single_for_cpu(&mdev->pdev->dev, dma, length, + dma_sync_single_for_cpu(priv->ddev, dma, length, DMA_FROM_DEVICE); skb_copy_to_linear_data(skb, va, length); - dma_sync_single_for_device(&mdev->pdev->dev, dma, length, + dma_sync_single_for_device(priv->ddev, dma, length, DMA_FROM_DEVICE); skb->tail += length; } else { |