From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dvora Fuxbrumer Date: Tue, 2 Mar 2021 10:22:58 +0200 Subject: [Intel-wired-lan] [PATCH net-next v6 9/9] igc: Add support for XDP_REDIRECT action In-Reply-To: <20210210215848.24514-10-vedang.patel@intel.com> References: <20210210215848.24514-1-vedang.patel@intel.com> <20210210215848.24514-10-vedang.patel@intel.com> Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: intel-wired-lan@osuosl.org List-ID: On 10/02/2021 23:58, Vedang Patel wrote: > From: Andre Guedes > > This patch adds support for the XDP_REDIRECT action which enables XDP > programs to redirect packets arriving at I225 NIC. It also implements > the ndo_xdp_xmit ops, enabling the igc driver to transmit packets > forwarded to it by xdp programs running on other interfaces. > > The patch tweaks the driver's page counting and recycling scheme as > described in the following two commits and implemented by other Intel > drivers in order to properly support XDP_REDIRECT action: > - 8ce29c679a6e i40e: tweak page counting for XDP_REDIRECT > - 75aab4e10ae6 i40e: avoid premature Rx buffer reuse > > This patch has been tested with the sample apps "xdp_redirect_cpu" and > "xdp_redirect_map" located in samples/bpf/. > > Signed-off-by: Andre Guedes > Reviewed-by: Maciej Fijalkowski > Signed-off-by: Vedang Patel > --- > drivers/net/ethernet/intel/igc/igc_main.c | 84 ++++++++++++++++++++--- > 1 file changed, 73 insertions(+), 11 deletions(-) > > diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c > index 90dae25dd5bb..2d7be4f2d48f 100644 > --- a/drivers/net/ethernet/intel/igc/igc_main.c > +++ b/drivers/net/ethernet/intel/igc/igc_main.c > @@ -26,6 +26,7 @@ > #define IGC_XDP_PASS 0 > #define IGC_XDP_CONSUMED BIT(0) > #define IGC_XDP_TX BIT(1) > +#define IGC_XDP_REDIRECT BIT(2) > > static int debug = -1; > > @@ -1506,11 +1507,18 @@ static void igc_process_skb_fields(struct igc_ring *rx_ring, > } > > static struct igc_rx_buffer *igc_get_rx_buffer(struct igc_ring *rx_ring, > - const unsigned int size) > + const unsigned int size, > + int *rx_buffer_pgcnt) > { > struct igc_rx_buffer *rx_buffer; > > rx_buffer = &rx_ring->rx_buffer_info[rx_ring->next_to_clean]; > + *rx_buffer_pgcnt = > +#if (PAGE_SIZE < 8192) > + page_count(rx_buffer->page); > +#else > + 0; > +#endif > prefetchw(rx_buffer->page); > > /* we are reusing so sync this buffer for CPU use */ > @@ -1678,7 +1686,8 @@ static void igc_reuse_rx_page(struct igc_ring *rx_ring, > new_buff->pagecnt_bias = old_buff->pagecnt_bias; > } > > -static bool igc_can_reuse_rx_page(struct igc_rx_buffer *rx_buffer) > +static bool igc_can_reuse_rx_page(struct igc_rx_buffer *rx_buffer, > + int rx_buffer_pgcnt) > { > unsigned int pagecnt_bias = rx_buffer->pagecnt_bias; > struct page *page = rx_buffer->page; > @@ -1689,7 +1698,7 @@ static bool igc_can_reuse_rx_page(struct igc_rx_buffer *rx_buffer) > > #if (PAGE_SIZE < 8192) > /* if we are only owner of page we can reuse it */ > - if (unlikely((page_ref_count(page) - pagecnt_bias) > 1)) > + if (unlikely((rx_buffer_pgcnt - pagecnt_bias) > 1)) > return false; > #else > #define IGC_LAST_OFFSET \ > @@ -1703,8 +1712,8 @@ static bool igc_can_reuse_rx_page(struct igc_rx_buffer *rx_buffer) > * the pagecnt_bias and page count so that we fully restock the > * number of references the driver holds. > */ > - if (unlikely(!pagecnt_bias)) { > - page_ref_add(page, USHRT_MAX); > + if (unlikely(pagecnt_bias == 1)) { > + page_ref_add(page, USHRT_MAX - 1); > rx_buffer->pagecnt_bias = USHRT_MAX; > } > > @@ -1777,9 +1786,10 @@ static bool igc_cleanup_headers(struct igc_ring *rx_ring, > } > > static void igc_put_rx_buffer(struct igc_ring *rx_ring, > - struct igc_rx_buffer *rx_buffer) > + struct igc_rx_buffer *rx_buffer, > + int rx_buffer_pgcnt) > { > - if (igc_can_reuse_rx_page(rx_buffer)) { > + if (igc_can_reuse_rx_page(rx_buffer, rx_buffer_pgcnt)) { > /* hand second half of page back to the ring */ > igc_reuse_rx_page(rx_ring, rx_buffer); > } else { > @@ -1845,7 +1855,8 @@ static bool igc_alloc_mapped_page(struct igc_ring *rx_ring, > bi->dma = dma; > bi->page = page; > bi->page_offset = igc_rx_offset(rx_ring); > - bi->pagecnt_bias = 1; > + page_ref_add(page, USHRT_MAX - 1); > + bi->pagecnt_bias = USHRT_MAX; > > return true; > } > @@ -2041,6 +2052,12 @@ static struct sk_buff *igc_xdp_run_prog(struct igc_adapter *adapter, > else > res = IGC_XDP_TX; > break; > + case XDP_REDIRECT: > + if (xdp_do_redirect(adapter->netdev, xdp, prog) < 0) > + res = IGC_XDP_CONSUMED; > + else > + res = IGC_XDP_REDIRECT; > + break; > default: > bpf_warn_invalid_xdp_action(act); > fallthrough; > @@ -2082,6 +2099,9 @@ static void igc_finalize_xdp(struct igc_adapter *adapter, int status) > igc_flush_tx_descriptors(ring); > __netif_tx_unlock(nq); > } > + > + if (status & IGC_XDP_REDIRECT) > + xdp_do_flush(); > } > > static int igc_clean_rx_irq(struct igc_q_vector *q_vector, const int budget) > @@ -2091,7 +2111,7 @@ static int igc_clean_rx_irq(struct igc_q_vector *q_vector, const int budget) > struct igc_ring *rx_ring = q_vector->rx.ring; > struct sk_buff *skb = rx_ring->skb; > u16 cleaned_count = igc_desc_unused(rx_ring); > - int xdp_status = 0; > + int xdp_status = 0, rx_buffer_pgcnt; > > while (likely(total_packets < budget)) { > union igc_adv_rx_desc *rx_desc; > @@ -2119,7 +2139,7 @@ static int igc_clean_rx_irq(struct igc_q_vector *q_vector, const int budget) > */ > dma_rmb(); > > - rx_buffer = igc_get_rx_buffer(rx_ring, size); > + rx_buffer = igc_get_rx_buffer(rx_ring, size, &rx_buffer_pgcnt); > truesize = igc_get_rx_frame_truesize(rx_ring, size); > > pktbuf = page_address(rx_buffer->page) + rx_buffer->page_offset; > @@ -2150,6 +2170,7 @@ static int igc_clean_rx_irq(struct igc_q_vector *q_vector, const int budget) > rx_buffer->pagecnt_bias++; > break; > case IGC_XDP_TX: > + case IGC_XDP_REDIRECT: > igc_rx_buffer_flip(rx_buffer, truesize); > xdp_status |= xdp_res; > break; > @@ -2172,7 +2193,7 @@ static int igc_clean_rx_irq(struct igc_q_vector *q_vector, const int budget) > break; > } > > - igc_put_rx_buffer(rx_ring, rx_buffer); > + igc_put_rx_buffer(rx_ring, rx_buffer, rx_buffer_pgcnt); > cleaned_count++; > > /* fetch next buffer in frame if non-eop */ > @@ -5114,6 +5135,46 @@ static int igc_bpf(struct net_device *dev, struct netdev_bpf *bpf) > } > } > > +static int igc_xdp_xmit(struct net_device *dev, int num_frames, > + struct xdp_frame **frames, u32 flags) > +{ > + struct igc_adapter *adapter = netdev_priv(dev); > + int cpu = smp_processor_id(); > + struct netdev_queue *nq; > + struct igc_ring *ring; > + int i, drops; > + > + if (unlikely(test_bit(__IGC_DOWN, &adapter->state))) > + return -ENETDOWN; > + > + if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK)) > + return -EINVAL; > + > + ring = igc_xdp_get_tx_ring(adapter, cpu); > + nq = txring_txq(ring); > + > + __netif_tx_lock(nq, cpu); > + > + drops = 0; > + for (i = 0; i < num_frames; i++) { > + int err; > + struct xdp_frame *xdpf = frames[i]; > + > + err = igc_xdp_init_tx_descriptor(ring, xdpf); > + if (err) { > + xdp_return_frame_rx_napi(xdpf); > + drops++; > + } > + } > + > + if (flags & XDP_XMIT_FLUSH) > + igc_flush_tx_descriptors(ring); > + > + __netif_tx_unlock(nq); > + > + return num_frames - drops; > +} > + > static const struct net_device_ops igc_netdev_ops = { > .ndo_open = igc_open, > .ndo_stop = igc_close, > @@ -5128,6 +5189,7 @@ static const struct net_device_ops igc_netdev_ops = { > .ndo_do_ioctl = igc_ioctl, > .ndo_setup_tc = igc_setup_tc, > .ndo_bpf = igc_bpf, > + .ndo_xdp_xmit = igc_xdp_xmit, > }; > > /* PCIe configuration access */ > Tested-by: Dvora Fuxbrumer