Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit f215af8c authored by Alexander Duyck's avatar Alexander Duyck Committed by Jeff Kirsher
Browse files

ixgbe: Only DMA sync frame length 



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: default avatarAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: default avatarAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: default avatarJeff Kirsher <jeffrey.t.kirsher@intel.com>
parent af43da0d

drivers/net/ethernet/intel/ixgbe/ixgbe_main.c

+5 −5
Original line number Diff line number Diff line
@@ -1841,7 +1841,7 @@ 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;
@@ -1983,12 +1983,11 @@ 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
@@ -2020,6 +2019,7 @@ 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;
@@ -2074,14 +2074,14 @@ 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) {