| Message ID | 168174343801.593471.10686331901576935015.stgit@firesoul (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | BPF |
| Headers | show |
| Series | XDP-hints: XDP kfunc metadata for driver igc | expand |
On Monday, April 17, 2023 10:57 PM, Jesper Dangaard Brouer <brouer@redhat.com> wrote: >The NIC hardware RX timestamping mechanism adds an optional tailored header >before the MAC header containing packet reception time. Optional depending on >RX descriptor TSIP status bit (IGC_RXDADV_STAT_TSIP). In case this bit is set >driver does offset adjustments to packet data start and extracts the timestamp. > >The timestamp need to be extracted before invoking the XDP bpf_prog, because >this area just before the packet is also accessible by XDP via data_meta context >pointer (and helper bpf_xdp_adjust_meta). Thus, an XDP bpf_prog can potentially >overwrite this and corrupt data that we want to extract with the new kfunc for >reading the timestamp. > >Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> >--- > drivers/net/ethernet/intel/igc/igc.h | 1 + > drivers/net/ethernet/intel/igc/igc_main.c | 20 ++++++++++++++++++++ > 2 files changed, 21 insertions(+) > >diff --git a/drivers/net/ethernet/intel/igc/igc.h >b/drivers/net/ethernet/intel/igc/igc.h >index c609a2e648f8..18d4af934d8c 100644 >--- a/drivers/net/ethernet/intel/igc/igc.h >+++ b/drivers/net/ethernet/intel/igc/igc.h >@@ -503,6 +503,7 @@ struct igc_rx_buffer { struct igc_xdp_buff { > struct xdp_buff xdp; > union igc_adv_rx_desc *rx_desc; >+ ktime_t rx_ts; /* data indication bit IGC_RXDADV_STAT_TSIP */ > }; > > struct igc_q_vector { >diff --git a/drivers/net/ethernet/intel/igc/igc_main.c >b/drivers/net/ethernet/intel/igc/igc_main.c >index 3a844cf5be3f..862768d5d134 100644 >--- a/drivers/net/ethernet/intel/igc/igc_main.c >+++ b/drivers/net/ethernet/intel/igc/igc_main.c >@@ -2552,6 +2552,7 @@ static int igc_clean_rx_irq(struct igc_q_vector *q_vector, const int budget) > if (igc_test_staterr(rx_desc, IGC_RXDADV_STAT_TSIP)) { > timestamp = igc_ptp_rx_pktstamp(q_vector->adapter, > pktbuf); >+ ctx.rx_ts = timestamp; > pkt_offset = IGC_TS_HDR_LEN; > size -= IGC_TS_HDR_LEN; > } >@@ -2740,6 +2741,7 @@ static int igc_clean_rx_irq_zc(struct igc_q_vector *q_vector, const int budget) > if (igc_test_staterr(desc, IGC_RXDADV_STAT_TSIP)) { > timestamp = igc_ptp_rx_pktstamp(q_vector->adapter, > bi->xdp->data); >+ ctx->rx_ts = timestamp; > > bi->xdp->data += IGC_TS_HDR_LEN; > >@@ -6492,6 +6494,23 @@ u32 igc_rd32(struct igc_hw *hw, u32 reg) > return value; > } > >+static int igc_xdp_rx_timestamp(const struct xdp_md *_ctx, u64 *timestamp) { >+ const struct igc_xdp_buff *ctx = (void *)_ctx; >+ >+ if (igc_test_staterr(ctx->rx_desc, IGC_RXDADV_STAT_TSIP)) { >+ *timestamp = ctx->rx_ts; >+ >+ return 0; >+ } >+ >+ return -ENODATA; >+} >+ >+const struct xdp_metadata_ops igc_xdp_metadata_ops = { Since igc_xdp_metadata_ops is used in igc_main.c only, suggest to make it static. Thanks & Regards Siang >+ .xmo_rx_timestamp = igc_xdp_rx_timestamp, >+}; >+ > /** > * igc_probe - Device Initialization Routine > * @pdev: PCI device information struct >@@ -6565,6 +6584,7 @@ static int igc_probe(struct pci_dev *pdev, > hw->hw_addr = adapter->io_addr; > > netdev->netdev_ops = &igc_netdev_ops; >+ netdev->xdp_metadata_ops = &igc_xdp_metadata_ops; > igc_ethtool_set_ops(netdev); > netdev->watchdog_timeo = 5 * HZ; > >
On 18/04/2023 06.16, Song, Yoong Siang wrote: > On Monday, April 17, 2023 10:57 PM, Jesper Dangaard Brouer<brouer@redhat.com> wrote: [...] >> diff --git a/drivers/net/ethernet/intel/igc/igc_main.c >> b/drivers/net/ethernet/intel/igc/igc_main.c >> index 3a844cf5be3f..862768d5d134 100644 >> --- a/drivers/net/ethernet/intel/igc/igc_main.c >> +++ b/drivers/net/ethernet/intel/igc/igc_main.c [...] >> >> +static int igc_xdp_rx_timestamp(const struct xdp_md *_ctx, u64 *timestamp) { >> + const struct igc_xdp_buff *ctx = (void *)_ctx; >> + >> + if (igc_test_staterr(ctx->rx_desc, IGC_RXDADV_STAT_TSIP)) { >> + *timestamp = ctx->rx_ts; >> + >> + return 0; >> + } >> + >> + return -ENODATA; >> +} >> + >> +const struct xdp_metadata_ops igc_xdp_metadata_ops = { > Since igc_xdp_metadata_ops is used in igc_main.c only, suggest to make it static. I agree, and I acknowledge that you have already pointed this our earier, but I forgot when I rebased the patches. Same for 4/5. --Jesper
diff --git a/drivers/net/ethernet/intel/igc/igc.h b/drivers/net/ethernet/intel/igc/igc.h index c609a2e648f8..18d4af934d8c 100644 --- a/drivers/net/ethernet/intel/igc/igc.h +++ b/drivers/net/ethernet/intel/igc/igc.h @@ -503,6 +503,7 @@ struct igc_rx_buffer { struct igc_xdp_buff { struct xdp_buff xdp; union igc_adv_rx_desc *rx_desc; + ktime_t rx_ts; /* data indication bit IGC_RXDADV_STAT_TSIP */ }; struct igc_q_vector { diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c index 3a844cf5be3f..862768d5d134 100644 --- a/drivers/net/ethernet/intel/igc/igc_main.c +++ b/drivers/net/ethernet/intel/igc/igc_main.c @@ -2552,6 +2552,7 @@ static int igc_clean_rx_irq(struct igc_q_vector *q_vector, const int budget) if (igc_test_staterr(rx_desc, IGC_RXDADV_STAT_TSIP)) { timestamp = igc_ptp_rx_pktstamp(q_vector->adapter, pktbuf); + ctx.rx_ts = timestamp; pkt_offset = IGC_TS_HDR_LEN; size -= IGC_TS_HDR_LEN; } @@ -2740,6 +2741,7 @@ static int igc_clean_rx_irq_zc(struct igc_q_vector *q_vector, const int budget) if (igc_test_staterr(desc, IGC_RXDADV_STAT_TSIP)) { timestamp = igc_ptp_rx_pktstamp(q_vector->adapter, bi->xdp->data); + ctx->rx_ts = timestamp; bi->xdp->data += IGC_TS_HDR_LEN; @@ -6492,6 +6494,23 @@ u32 igc_rd32(struct igc_hw *hw, u32 reg) return value; } +static int igc_xdp_rx_timestamp(const struct xdp_md *_ctx, u64 *timestamp) +{ + const struct igc_xdp_buff *ctx = (void *)_ctx; + + if (igc_test_staterr(ctx->rx_desc, IGC_RXDADV_STAT_TSIP)) { + *timestamp = ctx->rx_ts; + + return 0; + } + + return -ENODATA; +} + +const struct xdp_metadata_ops igc_xdp_metadata_ops = { + .xmo_rx_timestamp = igc_xdp_rx_timestamp, +}; + /** * igc_probe - Device Initialization Routine * @pdev: PCI device information struct @@ -6565,6 +6584,7 @@ static int igc_probe(struct pci_dev *pdev, hw->hw_addr = adapter->io_addr; netdev->netdev_ops = &igc_netdev_ops; + netdev->xdp_metadata_ops = &igc_xdp_metadata_ops; igc_ethtool_set_ops(netdev); netdev->watchdog_timeo = 5 * HZ;
The NIC hardware RX timestamping mechanism adds an optional tailored header before the MAC header containing packet reception time. Optional depending on RX descriptor TSIP status bit (IGC_RXDADV_STAT_TSIP). In case this bit is set driver does offset adjustments to packet data start and extracts the timestamp. The timestamp need to be extracted before invoking the XDP bpf_prog, because this area just before the packet is also accessible by XDP via data_meta context pointer (and helper bpf_xdp_adjust_meta). Thus, an XDP bpf_prog can potentially overwrite this and corrupt data that we want to extract with the new kfunc for reading the timestamp. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> --- drivers/net/ethernet/intel/igc/igc.h | 1 + drivers/net/ethernet/intel/igc/igc_main.c | 20 ++++++++++++++++++++ 2 files changed, 21 insertions(+)