[PATCH net-next] net: lan966x: Don't use xdp_frame when action is XDP_TX
From: Horatiu Vultur
Date: Thu Apr 20 2023 - 08:13:32 EST
When the action of an xdp program was XDP_TX, lan966x was creating
a xdp_frame and use this one to send the frame back. But it is also
possible to send back the frame without needing a xdp_frame, because
it possible to send it back using the page.
And then once the frame is transmitted is possible to use directly
page_pool_recycle_direct as lan966x is using page pools.
This would save some CPU usage on this path.
Signed-off-by: Horatiu Vultur <horatiu.vultur@xxxxxxxxxxxxx>
---
.../ethernet/microchip/lan966x/lan966x_fdma.c | 35 +++++++++++--------
.../ethernet/microchip/lan966x/lan966x_main.h | 2 ++
.../ethernet/microchip/lan966x/lan966x_xdp.c | 11 +++---
3 files changed, 27 insertions(+), 21 deletions(-)
diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c b/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c
index 2ed76bb61a731..7947259e67e4e 100644
--- a/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c
+++ b/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c
@@ -390,6 +390,7 @@ static void lan966x_fdma_stop_netdev(struct lan966x *lan966x)
static void lan966x_fdma_tx_clear_buf(struct lan966x *lan966x, int weight)
{
struct lan966x_tx *tx = &lan966x->tx;
+ struct lan966x_rx *rx = &lan966x->rx;
struct lan966x_tx_dcb_buf *dcb_buf;
struct xdp_frame_bulk bq;
struct lan966x_db *db;
@@ -432,7 +433,8 @@ static void lan966x_fdma_tx_clear_buf(struct lan966x *lan966x, int weight)
if (dcb_buf->xdp_ndo)
xdp_return_frame_bulk(dcb_buf->data.xdpf, &bq);
else
- xdp_return_frame_rx_napi(dcb_buf->data.xdpf);
+ page_pool_recycle_direct(rx->page_pool,
+ dcb_buf->data.page);
}
clear = true;
@@ -702,6 +704,7 @@ static void lan966x_fdma_tx_start(struct lan966x_tx *tx, int next_to_use)
int lan966x_fdma_xmit_xdpf(struct lan966x_port *port,
struct xdp_frame *xdpf,
struct page *page,
+ u32 len,
bool dma_map)
{
struct lan966x *lan966x = port->lan966x;
@@ -722,6 +725,15 @@ int lan966x_fdma_xmit_xdpf(struct lan966x_port *port,
goto out;
}
+ /* Fill up the buffer */
+ next_dcb_buf = &tx->dcbs_buf[next_to_use];
+ next_dcb_buf->use_skb = false;
+ next_dcb_buf->xdp_ndo = dma_map;
+ next_dcb_buf->len = len + IFH_LEN_BYTES;
+ next_dcb_buf->used = true;
+ next_dcb_buf->ptp = false;
+ next_dcb_buf->dev = port->dev;
+
/* Generate new IFH */
if (dma_map) {
if (xdpf->headroom < IFH_LEN_BYTES) {
@@ -736,16 +748,18 @@ int lan966x_fdma_xmit_xdpf(struct lan966x_port *port,
dma_addr = dma_map_single(lan966x->dev,
xdpf->data - IFH_LEN_BYTES,
- xdpf->len + IFH_LEN_BYTES,
+ len + IFH_LEN_BYTES,
DMA_TO_DEVICE);
if (dma_mapping_error(lan966x->dev, dma_addr)) {
ret = NETDEV_TX_OK;
goto out;
}
+ next_dcb_buf->data.xdpf = xdpf;
+
/* Setup next dcb */
lan966x_fdma_tx_setup_dcb(tx, next_to_use,
- xdpf->len + IFH_LEN_BYTES,
+ len + IFH_LEN_BYTES,
dma_addr);
} else {
ifh = page_address(page) + XDP_PACKET_HEADROOM;
@@ -756,25 +770,18 @@ int lan966x_fdma_xmit_xdpf(struct lan966x_port *port,
dma_addr = page_pool_get_dma_addr(page);
dma_sync_single_for_device(lan966x->dev,
dma_addr + XDP_PACKET_HEADROOM,
- xdpf->len + IFH_LEN_BYTES,
+ len + IFH_LEN_BYTES,
DMA_TO_DEVICE);
+ next_dcb_buf->data.page = page;
+
/* Setup next dcb */
lan966x_fdma_tx_setup_dcb(tx, next_to_use,
- xdpf->len + IFH_LEN_BYTES,
+ len + IFH_LEN_BYTES,
dma_addr + XDP_PACKET_HEADROOM);
}
- /* Fill up the buffer */
- next_dcb_buf = &tx->dcbs_buf[next_to_use];
- next_dcb_buf->use_skb = false;
- next_dcb_buf->data.xdpf = xdpf;
- next_dcb_buf->xdp_ndo = dma_map;
- next_dcb_buf->len = xdpf->len + IFH_LEN_BYTES;
next_dcb_buf->dma_addr = dma_addr;
- next_dcb_buf->used = true;
- next_dcb_buf->ptp = false;
- next_dcb_buf->dev = port->dev;
/* Start the transmission */
lan966x_fdma_tx_start(tx, next_to_use);
diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_main.h b/drivers/net/ethernet/microchip/lan966x/lan966x_main.h
index 851afb0166b19..59da35a2c93d4 100644
--- a/drivers/net/ethernet/microchip/lan966x/lan966x_main.h
+++ b/drivers/net/ethernet/microchip/lan966x/lan966x_main.h
@@ -243,6 +243,7 @@ struct lan966x_tx_dcb_buf {
union {
struct sk_buff *skb;
struct xdp_frame *xdpf;
+ struct page *page;
} data;
u32 len;
u32 used : 1;
@@ -544,6 +545,7 @@ int lan966x_fdma_xmit(struct sk_buff *skb, __be32 *ifh, struct net_device *dev);
int lan966x_fdma_xmit_xdpf(struct lan966x_port *port,
struct xdp_frame *frame,
struct page *page,
+ u32 len,
bool dma_map);
int lan966x_fdma_change_mtu(struct lan966x *lan966x);
void lan966x_fdma_netdev_init(struct lan966x *lan966x, struct net_device *dev);
diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_xdp.c b/drivers/net/ethernet/microchip/lan966x/lan966x_xdp.c
index 2e6f486ec67d7..a8ad1f4e431cb 100644
--- a/drivers/net/ethernet/microchip/lan966x/lan966x_xdp.c
+++ b/drivers/net/ethernet/microchip/lan966x/lan966x_xdp.c
@@ -62,7 +62,7 @@ int lan966x_xdp_xmit(struct net_device *dev,
struct xdp_frame *xdpf = frames[i];
int err;
- err = lan966x_fdma_xmit_xdpf(port, xdpf, NULL, true);
+ err = lan966x_fdma_xmit_xdpf(port, xdpf, NULL, xdpf->len, true);
if (err)
break;
@@ -76,7 +76,6 @@ int lan966x_xdp_run(struct lan966x_port *port, struct page *page, u32 data_len)
{
struct bpf_prog *xdp_prog = port->xdp_prog;
struct lan966x *lan966x = port->lan966x;
- struct xdp_frame *xdpf;
struct xdp_buff xdp;
u32 act;
@@ -90,11 +89,9 @@ int lan966x_xdp_run(struct lan966x_port *port, struct page *page, u32 data_len)
case XDP_PASS:
return FDMA_PASS;
case XDP_TX:
- xdpf = xdp_convert_buff_to_frame(&xdp);
- if (!xdpf)
- return FDMA_DROP;
-
- return lan966x_fdma_xmit_xdpf(port, xdpf, page, false) ?
+ return lan966x_fdma_xmit_xdpf(port, NULL, page,
+ data_len - IFH_LEN_BYTES,
+ false) ?
FDMA_DROP : FDMA_TX;
case XDP_REDIRECT:
if (xdp_do_redirect(port->dev, &xdp, xdp_prog))
--
2.38.0