[Intel-wired-lan] [next PATCH v2 02/11] ixgbe: Only DMA sync frame length
Alexander Duyck
alexander.duyck at gmail.com
Tue Jan 17 16:35:44 UTC 2017
From: Alexander Duyck <alexander.h.duyck at intel.com>
On some platforms, syncing a buffer for DMA is expensive. Rather than
sync the whole 2K receive buffer, only synchronise the length of the
frame, which will typically be the MTU, or a much smaller TCP ACK.
Signed-off-by: Alexander Duyck <alexander.h.duyck at intel.com>
---
drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index 452a407013ef..cfc097d07661 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -1858,7 +1858,7 @@ static void ixgbe_dma_sync_frag(struct ixgbe_ring *rx_ring,
dma_sync_single_range_for_cpu(rx_ring->dev,
IXGBE_CB(skb)->dma,
frag->page_offset,
- ixgbe_rx_bufsz(rx_ring),
+ skb_frag_size(frag),
DMA_FROM_DEVICE);
}
IXGBE_CB(skb)->dma = 0;
@@ -2000,12 +2000,11 @@ static bool ixgbe_can_reuse_rx_page(struct ixgbe_ring *rx_ring,
**/
static bool ixgbe_add_rx_frag(struct ixgbe_ring *rx_ring,
struct ixgbe_rx_buffer *rx_buffer,
- union ixgbe_adv_rx_desc *rx_desc,
+ unsigned int size,
struct sk_buff *skb)
{
struct page *page = rx_buffer->page;
unsigned char *va = page_address(page) + rx_buffer->page_offset;
- unsigned int size = le16_to_cpu(rx_desc->wb.upper.length);
#if (PAGE_SIZE < 8192)
unsigned int truesize = ixgbe_rx_bufsz(rx_ring);
#else
@@ -2037,6 +2036,7 @@ static bool ixgbe_add_rx_frag(struct ixgbe_ring *rx_ring,
static struct sk_buff *ixgbe_fetch_rx_buffer(struct ixgbe_ring *rx_ring,
union ixgbe_adv_rx_desc *rx_desc)
{
+ unsigned int size = le16_to_cpu(rx_desc->wb.upper.length);
struct ixgbe_rx_buffer *rx_buffer;
struct sk_buff *skb;
struct page *page;
@@ -2091,14 +2091,14 @@ static struct sk_buff *ixgbe_fetch_rx_buffer(struct ixgbe_ring *rx_ring,
dma_sync_single_range_for_cpu(rx_ring->dev,
rx_buffer->dma,
rx_buffer->page_offset,
- ixgbe_rx_bufsz(rx_ring),
+ size,
DMA_FROM_DEVICE);
rx_buffer->skb = NULL;
}
/* pull page into skb */
- if (ixgbe_add_rx_frag(rx_ring, rx_buffer, rx_desc, skb)) {
+ if (ixgbe_add_rx_frag(rx_ring, rx_buffer, size, skb)) {
/* hand second half of page back to the ring */
ixgbe_reuse_rx_page(rx_ring, rx_buffer);
} else if (IXGBE_CB(skb)->dma == rx_buffer->dma) {
More information about the Intel-wired-lan
mailing list