From 700f11eb2cbea349bda2599b4b676b49d43b4175 Mon Sep 17 00:00:00 2001 From: Horatiu Vultur Date: Sat, 22 Apr 2023 16:23:44 +0200 Subject: lan966x: Don't use xdp_frame when action is XDP_TX 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 is 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, which results in higher number of transmitted frames. Bellow are the statistics: Frame size: Improvement: 64 ~8% 256 ~11% 512 ~8% 1000 ~0% 1500 ~0% Signed-off-by: Horatiu Vultur Reviewed-by: Alexander Lobakin Link: https://lore.kernel.org/r/20230422142344.3630602-1-horatiu.vultur@microchip.com Signed-off-by: Jakub Kicinski --- .../net/ethernet/microchip/lan966x/lan966x_fdma.c | 35 ++++++++++++++-------- .../net/ethernet/microchip/lan966x/lan966x_main.h | 6 ++-- .../net/ethernet/microchip/lan966x/lan966x_xdp.c | 10 ++----- 3 files changed, 28 insertions(+), 23 deletions(-) (limited to 'drivers') diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c b/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c index 2ed76bb61a73..bd72fbc2220f 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; @@ -699,15 +701,14 @@ static void lan966x_fdma_tx_start(struct lan966x_tx *tx, int next_to_use) tx->last_in_use = next_to_use; } -int lan966x_fdma_xmit_xdpf(struct lan966x_port *port, - struct xdp_frame *xdpf, - struct page *page, - bool dma_map) +int lan966x_fdma_xmit_xdpf(struct lan966x_port *port, void *ptr, u32 len) { struct lan966x *lan966x = port->lan966x; struct lan966x_tx_dcb_buf *next_dcb_buf; struct lan966x_tx *tx = &lan966x->tx; + struct xdp_frame *xdpf; dma_addr_t dma_addr; + struct page *page; int next_to_use; __be32 *ifh; int ret = 0; @@ -722,8 +723,13 @@ int lan966x_fdma_xmit_xdpf(struct lan966x_port *port, goto out; } + /* Get the next buffer */ + next_dcb_buf = &tx->dcbs_buf[next_to_use]; + /* Generate new IFH */ - if (dma_map) { + if (!len) { + xdpf = ptr; + if (xdpf->headroom < IFH_LEN_BYTES) { ret = NETDEV_TX_OK; goto out; @@ -743,11 +749,16 @@ int lan966x_fdma_xmit_xdpf(struct lan966x_port *port, goto out; } + next_dcb_buf->data.xdpf = xdpf; + next_dcb_buf->len = xdpf->len + IFH_LEN_BYTES; + /* Setup next dcb */ lan966x_fdma_tx_setup_dcb(tx, next_to_use, xdpf->len + IFH_LEN_BYTES, dma_addr); } else { + page = ptr; + ifh = page_address(page) + XDP_PACKET_HEADROOM; memset(ifh, 0x0, sizeof(__be32) * IFH_LEN); lan966x_ifh_set_bypass(ifh, 1); @@ -756,21 +767,21 @@ 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; + next_dcb_buf->len = len + IFH_LEN_BYTES; + /* 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->xdp_ndo = !len; next_dcb_buf->dma_addr = dma_addr; next_dcb_buf->used = true; next_dcb_buf->ptp = false; diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_main.h b/drivers/net/ethernet/microchip/lan966x/lan966x_main.h index 851afb0166b1..c977c70abc3d 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; @@ -541,10 +542,7 @@ int lan966x_ptp_setup_traps(struct lan966x_port *port, struct ifreq *ifr); int lan966x_ptp_del_traps(struct lan966x_port *port); 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, - bool dma_map); +int lan966x_fdma_xmit_xdpf(struct lan966x_port *port, void *ptr, u32 len); int lan966x_fdma_change_mtu(struct lan966x *lan966x); void lan966x_fdma_netdev_init(struct lan966x *lan966x, struct net_device *dev); void lan966x_fdma_netdev_deinit(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 2e6f486ec67d..9ee61db8690b 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, 0); 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 +89,8 @@ 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, page, + data_len - IFH_LEN_BYTES) ? FDMA_DROP : FDMA_TX; case XDP_REDIRECT: if (xdp_do_redirect(port->dev, &xdp, xdp_prog)) -- cgit v1.2.3