From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ivan Khoronzhuk Subject: Re: [PATCH net-next 3/3] net: ethernet: ti: cpsw: add XDP support Date: Mon, 27 May 2019 21:29:25 +0300 Message-ID: <20190527182924.GC4246@khorivan> References: <20190523182035.9283-1-ivan.khoronzhuk@linaro.org> <20190523182035.9283-4-ivan.khoronzhuk@linaro.org> <6a88616b-9a49-77c3-577e-40670f62f953@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Return-path: Content-Disposition: inline In-Reply-To: <6a88616b-9a49-77c3-577e-40670f62f953@ti.com> Sender: linux-kernel-owner@vger.kernel.org To: grygorii Cc: hawk@kernel.org, davem@davemloft.net, ast@kernel.org, linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org, xdp-newbies@vger.kernel.org, ilias.apalodimas@linaro.org, netdev@vger.kernel.org, daniel@iogearbox.net, jakub.kicinski@netronome.com, john.fastabend@gmail.com List-Id: linux-omap@vger.kernel.org On Fri, May 24, 2019 at 08:49:38PM +0300, grygorii wrote: >Hi Ivan, > >On 23/05/2019 21:20, Ivan Khoronzhuk wrote: >>Add XDP support based on rx page_pool allocator, one frame per page. >>Page pool allocator is used with assumption that only one rx_handler >>is running simultaneously. DMA map/unmap is reused from page pool >>despite there is no need to map whole page. >> >>Due to specific of cpsw, the same TX/RX handler can be used by 2 >>network devices, so special fields in buffer are added to identify >>an interface the frame is destined to. Thus XDP works for both >>interfaces, that allows to test xdp redirect between two interfaces >>easily. >> >>XDP prog is common for all channels till appropriate changes are added >>in XDP infrastructure. >> >>Signed-off-by: Ivan Khoronzhuk >>--- >> drivers/net/ethernet/ti/Kconfig | 1 + >> drivers/net/ethernet/ti/cpsw.c | 555 ++++++++++++++++++++++--- >> drivers/net/ethernet/ti/cpsw_ethtool.c | 53 +++ >> drivers/net/ethernet/ti/cpsw_priv.h | 7 + >> 4 files changed, 554 insertions(+), 62 deletions(-) >> >>diff --git a/drivers/net/ethernet/ti/Kconfig b/drivers/net/ethernet/ti/Kconfig >>index bd05a977ee7e..3cb8c5214835 100644 >>--- a/drivers/net/ethernet/ti/Kconfig >>+++ b/drivers/net/ethernet/ti/Kconfig >>@@ -50,6 +50,7 @@ config TI_CPSW >> depends on ARCH_DAVINCI || ARCH_OMAP2PLUS || COMPILE_TEST >> select TI_DAVINCI_MDIO >> select MFD_SYSCON >>+ select PAGE_POOL >> select REGMAP >> ---help--- >> This driver supports TI's CPSW Ethernet Switch. >>diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c >>index 87a600aeee4a..274e6b64ea9e 100644 >>--- a/drivers/net/ethernet/ti/cpsw.c >>+++ b/drivers/net/ethernet/ti/cpsw.c >>@@ -31,6 +31,10 @@ >> #include >> #include >> #include >>+#include >>+#include >>+#include >>+#include >> #include >> #include >>@@ -60,6 +64,10 @@ static int descs_pool_size = CPSW_CPDMA_DESCS_POOL_SIZE_DEFAULT; >> module_param(descs_pool_size, int, 0444); >> MODULE_PARM_DESC(descs_pool_size, "Number of CPDMA CPPI descriptors in pool"); >>+/* The buf includes headroom compatible with both skb and xdpf */ >>+#define CPSW_HEADROOM_NA (max(XDP_PACKET_HEADROOM, NET_SKB_PAD) + NET_IP_ALIGN) >>+#define CPSW_HEADROOM ALIGN(CPSW_HEADROOM_NA, sizeof(long)) >>+ >> #define for_each_slave(priv, func, arg...) \ >> do { \ >> struct cpsw_slave *slave; \ >>@@ -74,6 +82,8 @@ MODULE_PARM_DESC(descs_pool_size, "Number of CPDMA CPPI descriptors in pool"); >> (func)(slave++, ##arg); \ >> } while (0) >>+#define CPSW_XMETA_OFFSET ALIGN(sizeof(struct xdp_frame), sizeof(long)) >>+ >> static int cpsw_ndo_vlan_rx_add_vid(struct net_device *ndev, >> __be16 proto, u16 vid); >>@@ -337,24 +347,58 @@ void cpsw_intr_disable(struct cpsw_common *cpsw) >> return; >> } > >[..] > >>+static int cpsw_xdp_tx_frame_mapped(struct cpsw_priv *priv, >>+ struct xdp_frame *xdpf, struct page *page) >>+{ >>+ struct cpsw_common *cpsw = priv->cpsw; >>+ struct cpsw_meta_xdp *xmeta; >>+ struct netdev_queue *txq; >>+ struct cpdma_chan *txch; >>+ dma_addr_t dma; >>+ int ret; >>+ >>+ xmeta = (void *)xdpf + CPSW_XMETA_OFFSET; >>+ xmeta->ch = 0; >>+ >>+ txch = cpsw->txv[0].ch; >>+ dma = (xdpf->data - (void *)xdpf) + page->dma_addr; >>+ ret = cpdma_chan_submit_mapped(txch, cpsw_xdpf_to_handle(xdpf), dma, >>+ xdpf->len, >>+ priv->emac_port + cpsw->data.dual_emac); >>+ if (ret) { >>+ xdp_return_frame_rx_napi(xdpf); >>+ goto stop; >>+ } >>+ >>+ /* no tx desc - stop sending us tx frames */ >>+ if (unlikely(!cpdma_check_free_tx_desc(txch))) >>+ goto stop; >>+ >>+ return ret; >>+stop: >>+ txq = netdev_get_tx_queue(priv->ndev, 0); >>+ netif_tx_stop_queue(txq); >>+ >>+ /* Barrier, so that stop_queue visible to other cpus */ >>+ smp_mb__after_atomic(); >>+ >>+ if (cpdma_check_free_tx_desc(txch)) >>+ netif_tx_wake_queue(txq); >>+ >>+ return ret; >>+} >>+ >>+static int cpsw_xdp_tx_frame(struct cpsw_priv *priv, struct xdp_frame *xdpf) >>+{ >>+ struct cpsw_common *cpsw = priv->cpsw; >>+ struct cpsw_meta_xdp *xmeta; >>+ struct netdev_queue *txq; >>+ struct cpdma_chan *txch; >>+ int ret; >>+ >>+ xmeta = (void *)xdpf + CPSW_XMETA_OFFSET; >>+ if (sizeof(*xmeta) > xdpf->headroom) >>+ return -EINVAL; >>+ >>+ xmeta->ndev = priv->ndev; >>+ xmeta->ch = 0; >>+ >>+ txch = cpsw->txv[0].ch; >>+ ret = cpdma_chan_submit(txch, cpsw_xdpf_to_handle(xdpf), xdpf->data, >>+ xdpf->len, >>+ priv->emac_port + cpsw->data.dual_emac); >>+ if (ret) { >>+ xdp_return_frame_rx_napi(xdpf); >>+ goto stop; >>+ } >>+ >>+ /* no tx desc - stop sending us tx frames */ >>+ if (unlikely(!cpdma_check_free_tx_desc(txch))) >>+ goto stop; >>+ >>+ return ret; >>+stop: >>+ txq = netdev_get_tx_queue(priv->ndev, 0); >>+ netif_tx_stop_queue(txq); >>+ >>+ /* Barrier, so that stop_queue visible to other cpus */ >>+ smp_mb__after_atomic(); >>+ >>+ if (cpdma_check_free_tx_desc(txch)) >>+ netif_tx_wake_queue(txq); >>+ >>+ return ret; >>+} > >Above 2 functions are mostly identical - could you do smth. with it? ... I know it should be, but i hadn't found better way for combining them .... > >>+ >>+static int cpsw_run_xdp(struct cpsw_priv *priv, struct cpsw_vector *rxv, >>+ struct xdp_buff *xdp, struct page *page) >>+{ >>+ struct net_device *ndev = priv->ndev; >>+ struct xdp_frame *xdpf; >>+ struct bpf_prog *prog; >>+ int ret = 1; >>+ u32 act; >>+ >>+ rcu_read_lock(); >>+ >>+ prog = READ_ONCE(priv->xdp_prog); >>+ if (!prog) { >>+ ret = 0; >>+ goto out; >>+ } >>+ >>+ act = bpf_prog_run_xdp(prog, xdp); >>+ switch (act) { >>+ case XDP_PASS: >>+ ret = 0; >>+ break; >>+ case XDP_TX: >>+ xdpf = convert_to_xdp_frame(xdp); >>+ if (unlikely(!xdpf)) >>+ xdp_return_buff(xdp); >>+ else >>+ cpsw_xdp_tx_frame_mapped(priv, xdpf, page); >>+ break; >>+ case XDP_REDIRECT: >>+ if (xdp_do_redirect(ndev, xdp, prog)) >>+ xdp_return_buff(xdp); >>+ else >>+ ret = 2; > >could we avoid using consts as return values? >may be some informative defines/enum? Ok, for all "const" cases. -- Regards, Ivan Khoronzhuk