On Tue, 22 Oct 2019 16:37:53 +0100
Charles McLachlan <cmclach...@solarflare.com> wrote:
> Add a field to efx_tx_buffer so that we can track xdp_frames. Add a
> flag so that buffers that contain xdp_frames can be identified and
> passed to xdp_return_frame.
>
> Signed-off-by: Charles McLachlan <cmclach...@solarflare.com>
> ---
> drivers/net/ethernet/sfc/net_driver.h | 10 ++++++++--
> drivers/net/ethernet/sfc/tx.c | 2 ++
> 2 files changed, 10 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/ethernet/sfc/net_driver.h
> b/drivers/net/ethernet/sfc/net_driver.h
> index 284a1b047ac2..7394d901e021 100644
> --- a/drivers/net/ethernet/sfc/net_driver.h
> +++ b/drivers/net/ethernet/sfc/net_driver.h
> @@ -27,6 +27,7 @@
> #include <linux/i2c.h>
> #include <linux/mtd/mtd.h>
> #include <net/busy_poll.h>
> +#include <net/xdp.h>
>
> #include "enum.h"
> #include "bitfield.h"
> @@ -136,7 +137,8 @@ struct efx_special_buffer {
> * struct efx_tx_buffer - buffer state for a TX descriptor
> * @skb: When @flags & %EFX_TX_BUF_SKB, the associated socket buffer to be
> * freed when descriptor completes
> - * @option: When @flags & %EFX_TX_BUF_OPTION, a NIC-specific option
> descriptor.
> + * @xdpf: When @flags & %EFX_TX_BUF_XDP, the XDP frame information; its @data
> + * member is the associated buffer to drop a page reference on.
> * @dma_addr: DMA address of the fragment.
> * @flags: Flags for allocation and DMA mapping type
> * @len: Length of this fragment.
> @@ -146,7 +148,10 @@ struct efx_special_buffer {
> * Only valid if @unmap_len != 0.
> */
> struct efx_tx_buffer {
> - const struct sk_buff *skb;
> + union {
> + const struct sk_buff *skb;
> + struct xdp_frame *xdpf;
> + };
> union {
> efx_qword_t option;
> dma_addr_t dma_addr;
> @@ -160,6 +165,7 @@ struct efx_tx_buffer {
> #define EFX_TX_BUF_SKB 2 /* buffer is last part of skb */
> #define EFX_TX_BUF_MAP_SINGLE 8 /* buffer was mapped with
> dma_map_single() */
> #define EFX_TX_BUF_OPTION 0x10 /* empty buffer for option descriptor */
> +#define EFX_TX_BUF_XDP 0x20 /* buffer was sent with XDP */
>
> /**
> * struct efx_tx_queue - An Efx TX queue
> diff --git a/drivers/net/ethernet/sfc/tx.c b/drivers/net/ethernet/sfc/tx.c
> index 65e81ec1b314..9905e8952a45 100644
> --- a/drivers/net/ethernet/sfc/tx.c
> +++ b/drivers/net/ethernet/sfc/tx.c
> @@ -95,6 +95,8 @@ static void efx_dequeue_buffer(struct efx_tx_queue
> *tx_queue,
> netif_vdbg(tx_queue->efx, tx_done, tx_queue->efx->net_dev,
> "TX queue %d transmission id %x complete\n",
> tx_queue->queue, tx_queue->read_count);
> + } else if (buffer->flags & EFX_TX_BUF_XDP) {
> + xdp_return_frame(buffer->xdpf);
Is this efx_dequeue_buffer() function always called under NAPI protection?
(So it could use the faster xdp_return_frame_rx_napi() ... ?)
> }
>
> buffer->len = 0;
--
Best regards,
Jesper Dangaard Brouer
MSc.CS, Principal Kernel Engineer at Red Hat
LinkedIn: http://www.linkedin.com/in/brouer
