[PATCH v2 net-next 0/7] Extend socket timestamping API

[PATCH v2 net-next 0/7] Extend socket timestamping API

[Miroslav Lichvar]

Changes v1->v2:
- added separate patch for new NAPI functions 
- split code from __sock_recv_timestamp() for better readability
- fixed RCU locking
- fixed compiler warning (missing case in switch in first patch)
- inline sw_tx_timestamp() in its only user

Changes RFC->v1:
- reworked SOF_TIMESTAMPING_OPT_PKTINFO patch to not add new fields to
  skb shared info (net device is now looked up by napi_id), not require
  any changes in drivers, and restrict the cmsg to incoming packets
- renamed SOF_TIMESTAMPING_OPT_MULTIMSG to SOF_TIMESTAMPING_OPT_TX_SWHW
  and fixed its description
- moved struct scm_ts_pktinfo from errqueue.h to net_tstamp.h as it
  can't be received from the error queue anymore
- improved commit descriptions and removed incorrect comment

This patchset adds new options to the timestamping API that will be
useful for NTP implementations and possibly other applications.

The first patch specifies a timestamp filter for NTP packets. The second
patch updates drivers that can timestamp all packets, or need to list
the filter as unsupported. There is no attempt to add the support to the
phyter driver.

The third patch adds two helper functions working with NAPI ID, which is
needed by the next patch. The fourth patch adds a new option to get a
new control message with the L2 length and interface index for incoming
packets with hardware timestamps.

The fifth patch fixes the code to not make a false software TX timestamp
when hardware timestamping is enabled. The sixth patch depends on this
fix.

The sixth patch adds a new option to request both software and hardware
timestamps for outgoing packets. The seventh patch updates drivers that
assumed software timestamping cannot be used together with hardware
timestamping.

The patches have been tested on x86_64 machines with igb and e1000e
drivers.

Miroslav Lichvar (7):
  net: define receive timestamp filter for NTP
  net: ethernet: update drivers to handle HWTSTAMP_FILTER_NTP_ALL
  net: add function to retrieve original skb device using NAPI ID
  net: add new control message for incoming HW-timestamped packets
  net: don't make false software transmit timestamps
  net: allow simultaneous SW and HW transmit timestamping
  net: ethernet: update drivers to make both SW and HW TX timestamps

 Documentation/networking/timestamping.txt          | 22 ++++++++++-
 drivers/net/ethernet/amd/xgbe/xgbe-drv.c           |  4 +-
 drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c   |  1 +
 drivers/net/ethernet/cavium/liquidio/lio_main.c    |  1 +
 drivers/net/ethernet/cavium/liquidio/lio_vf_main.c |  1 +
 drivers/net/ethernet/cavium/octeon/octeon_mgmt.c   |  1 +
 drivers/net/ethernet/intel/e1000e/netdev.c         |  5 ++-
 drivers/net/ethernet/intel/i40e/i40e_ptp.c         |  1 +
 drivers/net/ethernet/intel/igb/igb_ptp.c           |  1 +
 drivers/net/ethernet/intel/ixgbe/ixgbe_ptp.c       |  1 +
 drivers/net/ethernet/mellanox/mlx4/en_netdev.c     |  1 +
 drivers/net/ethernet/mellanox/mlx5/core/en_clock.c |  1 +
 drivers/net/ethernet/neterion/vxge/vxge-main.c     |  1 +
 drivers/net/ethernet/qlogic/qede/qede_ptp.c        |  1 +
 drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c    |  3 +-
 drivers/net/ethernet/sfc/ef10.c                    |  1 +
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c  |  7 ++--
 drivers/net/ethernet/ti/cpsw.c                     |  1 +
 drivers/net/ethernet/tile/tilegx.c                 |  1 +
 include/linux/netdevice.h                          |  1 +
 include/linux/skbuff.h                             | 19 ++++++----
 include/uapi/asm-generic/socket.h                  |  2 +
 include/uapi/linux/net_tstamp.h                    | 13 ++++++-
 net/core/dev.c                                     | 26 +++++++++++++
 net/core/dev_ioctl.c                               |  1 +
 net/core/skbuff.c                                  |  4 ++
 net/socket.c                                       | 44 +++++++++++++++++++++-
 27 files changed, 142 insertions(+), 23 deletions(-)

-- 
2.9.3

[PATCH v2 net-next 1/7] net: define receive timestamp filter for NTP

[Miroslav Lichvar]

Add HWTSTAMP_FILTER_NTP_ALL to the hwtstamp_rx_filters enum for
timestamping of NTP packets. There is currently only one driver
(phyter) that could support it directly.

CC: Richard Cochran <richardcochran@gmail.com>
CC: Willem de Bruijn <willemb@google.com>
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
---
 include/uapi/linux/net_tstamp.h | 3 +++
 net/core/dev_ioctl.c            | 2 ++
 2 files changed, 5 insertions(+)

diff --git a/include/uapi/linux/net_tstamp.h b/include/uapi/linux/net_tstamp.h
index 464dcca..0749fb1 100644
--- a/include/uapi/linux/net_tstamp.h
+++ b/include/uapi/linux/net_tstamp.h
@@ -125,6 +125,9 @@ enum hwtstamp_rx_filters {
 	HWTSTAMP_FILTER_PTP_V2_SYNC,
 	/* PTP v2/802.AS1, any layer, Delay_req packet */
 	HWTSTAMP_FILTER_PTP_V2_DELAY_REQ,
+
+	/* NTP, UDP, all versions and packet modes */
+	HWTSTAMP_FILTER_NTP_ALL,
 };
 
 #endif /* _NET_TIMESTAMPING_H */
diff --git a/net/core/dev_ioctl.c b/net/core/dev_ioctl.c
index b94b1d2..8f036a7 100644
--- a/net/core/dev_ioctl.c
+++ b/net/core/dev_ioctl.c
@@ -227,6 +227,8 @@ static int net_hwtstamp_validate(struct ifreq *ifr)
 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
 		rx_filter_valid = 1;
 		break;
+	case HWTSTAMP_FILTER_NTP_ALL:
+		break;
 	}
 
 	if (!tx_type_valid || !rx_filter_valid)
-- 
2.9.3

[PATCH v2 net-next 2/7] net: ethernet: update drivers to handle HWTSTAMP_FILTER_NTP_ALL

[Miroslav Lichvar]

Include HWTSTAMP_FILTER_NTP_ALL in net_hwtstamp_validate() as a valid
filter and update drivers which can timestamp all packets, or which
explicitly list unsupported filters instead of using a default case, to
handle the filter.

CC: Richard Cochran <richardcochran@gmail.com>
CC: Willem de Bruijn <willemb@google.com>
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
---
 drivers/net/ethernet/amd/xgbe/xgbe-drv.c           | 1 +
 drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c   | 1 +
 drivers/net/ethernet/cavium/liquidio/lio_main.c    | 1 +
 drivers/net/ethernet/cavium/liquidio/lio_vf_main.c | 1 +
 drivers/net/ethernet/cavium/octeon/octeon_mgmt.c   | 1 +
 drivers/net/ethernet/intel/e1000e/netdev.c         | 1 +
 drivers/net/ethernet/intel/i40e/i40e_ptp.c         | 1 +
 drivers/net/ethernet/intel/igb/igb_ptp.c           | 1 +
 drivers/net/ethernet/intel/ixgbe/ixgbe_ptp.c       | 1 +
 drivers/net/ethernet/mellanox/mlx4/en_netdev.c     | 1 +
 drivers/net/ethernet/mellanox/mlx5/core/en_clock.c | 1 +
 drivers/net/ethernet/neterion/vxge/vxge-main.c     | 1 +
 drivers/net/ethernet/qlogic/qede/qede_ptp.c        | 1 +
 drivers/net/ethernet/sfc/ef10.c                    | 1 +
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c  | 1 +
 drivers/net/ethernet/ti/cpsw.c                     | 1 +
 drivers/net/ethernet/tile/tilegx.c                 | 1 +
 net/core/dev_ioctl.c                               | 3 +--
 18 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-drv.c b/drivers/net/ethernet/amd/xgbe/xgbe-drv.c
index c772420..89b21d7 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe-drv.c
+++ b/drivers/net/ethernet/amd/xgbe/xgbe-drv.c
@@ -1268,6 +1268,7 @@ static int xgbe_set_hwtstamp_settings(struct xgbe_prv_data *pdata,
 	case HWTSTAMP_FILTER_NONE:
 		break;
 
+	case HWTSTAMP_FILTER_NTP_ALL:
 	case HWTSTAMP_FILTER_ALL:
 		XGMAC_SET_BITS(mac_tscr, MAC_TSCR, TSENALL, 1);
 		XGMAC_SET_BITS(mac_tscr, MAC_TSCR, TSENA, 1);
diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
index a851f95..2f30b1a 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
@@ -15351,6 +15351,7 @@ int bnx2x_configure_ptp_filters(struct bnx2x *bp)
 		break;
 	case HWTSTAMP_FILTER_ALL:
 	case HWTSTAMP_FILTER_SOME:
+	case HWTSTAMP_FILTER_NTP_ALL:
 		bp->rx_filter = HWTSTAMP_FILTER_NONE;
 		break;
 	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
diff --git a/drivers/net/ethernet/cavium/liquidio/lio_main.c b/drivers/net/ethernet/cavium/liquidio/lio_main.c
index 927617c..7a0ef5b 100644
--- a/drivers/net/ethernet/cavium/liquidio/lio_main.c
+++ b/drivers/net/ethernet/cavium/liquidio/lio_main.c
@@ -3020,6 +3020,7 @@ static int hwtstamp_ioctl(struct net_device *netdev, struct ifreq *ifr)
 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
+	case HWTSTAMP_FILTER_NTP_ALL:
 		conf.rx_filter = HWTSTAMP_FILTER_ALL;
 		break;
 	default:
diff --git a/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c b/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c
index 34c7782..15e21b5 100644
--- a/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c
+++ b/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c
@@ -2100,6 +2100,7 @@ static int hwtstamp_ioctl(struct net_device *netdev, struct ifreq *ifr)
 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
+	case HWTSTAMP_FILTER_NTP_ALL:
 		conf.rx_filter = HWTSTAMP_FILTER_ALL;
 		break;
 	default:
diff --git a/drivers/net/ethernet/cavium/octeon/octeon_mgmt.c b/drivers/net/ethernet/cavium/octeon/octeon_mgmt.c
index a213868..2887bca 100644
--- a/drivers/net/ethernet/cavium/octeon/octeon_mgmt.c
+++ b/drivers/net/ethernet/cavium/octeon/octeon_mgmt.c
@@ -755,6 +755,7 @@ static int octeon_mgmt_ioctl_hwtstamp(struct net_device *netdev,
 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
+	case HWTSTAMP_FILTER_NTP_ALL:
 		p->has_rx_tstamp = have_hw_timestamps;
 		config.rx_filter = HWTSTAMP_FILTER_ALL;
 		if (p->has_rx_tstamp) {
diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c
index b367972..0ff9295 100644
--- a/drivers/net/ethernet/intel/e1000e/netdev.c
+++ b/drivers/net/ethernet/intel/e1000e/netdev.c
@@ -3680,6 +3680,7 @@ static int e1000e_config_hwtstamp(struct e1000_adapter *adapter,
 		 * Delay Request messages but not both so fall-through to
 		 * time stamp all packets.
 		 */
+	case HWTSTAMP_FILTER_NTP_ALL:
 	case HWTSTAMP_FILTER_ALL:
 		is_l2 = true;
 		is_l4 = true;
diff --git a/drivers/net/ethernet/intel/i40e/i40e_ptp.c b/drivers/net/ethernet/intel/i40e/i40e_ptp.c
index 18c1cc0..0efff18 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_ptp.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_ptp.c
@@ -562,6 +562,7 @@ static int i40e_ptp_set_timestamp_mode(struct i40e_pf *pf,
 			config->rx_filter = HWTSTAMP_FILTER_PTP_V2_L2_EVENT;
 		}
 		break;
+	case HWTSTAMP_FILTER_NTP_ALL:
 	case HWTSTAMP_FILTER_ALL:
 	default:
 		return -ERANGE;
diff --git a/drivers/net/ethernet/intel/igb/igb_ptp.c b/drivers/net/ethernet/intel/igb/igb_ptp.c
index 7a3fd4d..d333d6d 100644
--- a/drivers/net/ethernet/intel/igb/igb_ptp.c
+++ b/drivers/net/ethernet/intel/igb/igb_ptp.c
@@ -941,6 +941,7 @@ static int igb_ptp_set_timestamp_mode(struct igb_adapter *adapter,
 		is_l4 = true;
 		break;
 	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
+	case HWTSTAMP_FILTER_NTP_ALL:
 	case HWTSTAMP_FILTER_ALL:
 		/* 82576 cannot timestamp all packets, which it needs to do to
 		 * support both V1 Sync and Delay_Req messages
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_ptp.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_ptp.c
index ef0635e..d44c728 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_ptp.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_ptp.c
@@ -883,6 +883,7 @@ static int ixgbe_ptp_set_timestamp_mode(struct ixgbe_adapter *adapter,
 				   IXGBE_FLAG_RX_HWTSTAMP_IN_REGISTER);
 		break;
 	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
+	case HWTSTAMP_FILTER_NTP_ALL:
 	case HWTSTAMP_FILTER_ALL:
 		/* The X550 controller is capable of timestamping all packets,
 		 * which allows it to accept any filter.
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
index 94fab20..8243674 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
@@ -2375,6 +2375,7 @@ static int mlx4_en_hwtstamp_set(struct net_device *dev, struct ifreq *ifr)
 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
+	case HWTSTAMP_FILTER_NTP_ALL:
 		config.rx_filter = HWTSTAMP_FILTER_ALL;
 		break;
 	default:
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_clock.c b/drivers/net/ethernet/mellanox/mlx5/core/en_clock.c
index e706a87..e294944 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_clock.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_clock.c
@@ -128,6 +128,7 @@ int mlx5e_hwstamp_set(struct net_device *dev, struct ifreq *ifr)
 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
+	case HWTSTAMP_FILTER_NTP_ALL:
 		/* Disable CQE compression */
 		netdev_warn(dev, "Disabling cqe compression");
 		err = mlx5e_modify_rx_cqe_compression_locked(priv, false);
diff --git a/drivers/net/ethernet/neterion/vxge/vxge-main.c b/drivers/net/ethernet/neterion/vxge/vxge-main.c
index 6a4310a..50ea69d 100644
--- a/drivers/net/ethernet/neterion/vxge/vxge-main.c
+++ b/drivers/net/ethernet/neterion/vxge/vxge-main.c
@@ -3218,6 +3218,7 @@ static int vxge_hwtstamp_set(struct vxgedev *vdev, void __user *data)
 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
+	case HWTSTAMP_FILTER_NTP_ALL:
 		if (vdev->devh->config.hwts_en != VXGE_HW_HWTS_ENABLE)
 			return -EFAULT;
 
diff --git a/drivers/net/ethernet/qlogic/qede/qede_ptp.c b/drivers/net/ethernet/qlogic/qede/qede_ptp.c
index 6396363..3847671 100644
--- a/drivers/net/ethernet/qlogic/qede/qede_ptp.c
+++ b/drivers/net/ethernet/qlogic/qede/qede_ptp.c
@@ -235,6 +235,7 @@ static int qede_ptp_cfg_filters(struct qede_dev *edev)
 		break;
 	case HWTSTAMP_FILTER_ALL:
 	case HWTSTAMP_FILTER_SOME:
+	case HWTSTAMP_FILTER_NTP_ALL:
 		ptp->rx_filter = HWTSTAMP_FILTER_NONE;
 		break;
 	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
diff --git a/drivers/net/ethernet/sfc/ef10.c b/drivers/net/ethernet/sfc/ef10.c
index 78efb28..ad9c4de 100644
--- a/drivers/net/ethernet/sfc/ef10.c
+++ b/drivers/net/ethernet/sfc/ef10.c
@@ -6068,6 +6068,7 @@ static int efx_ef10_ptp_set_ts_config(struct efx_nic *efx,
 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
+	case HWTSTAMP_FILTER_NTP_ALL:
 		init->rx_filter = HWTSTAMP_FILTER_ALL;
 		rc = efx_ptp_change_mode(efx, true, 0);
 		if (!rc)
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index cd8c601..3115700 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -644,6 +644,7 @@ static int stmmac_hwtstamp_ioctl(struct net_device *dev, struct ifreq *ifr)
 			ptp_over_ethernet = PTP_TCR_TSIPENA;
 			break;
 
+		case HWTSTAMP_FILTER_NTP_ALL:
 		case HWTSTAMP_FILTER_ALL:
 			/* time stamp any incoming packet */
 			config.rx_filter = HWTSTAMP_FILTER_ALL;
diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
index fa674a8..8da70fa 100644
--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -1718,6 +1718,7 @@ static int cpsw_hwtstamp_set(struct net_device *dev, struct ifreq *ifr)
 	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
 	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
 	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
+	case HWTSTAMP_FILTER_NTP_ALL:
 		return -ERANGE;
 	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
 	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
diff --git a/drivers/net/ethernet/tile/tilegx.c b/drivers/net/ethernet/tile/tilegx.c
index 7c634bc..aec9538 100644
--- a/drivers/net/ethernet/tile/tilegx.c
+++ b/drivers/net/ethernet/tile/tilegx.c
@@ -512,6 +512,7 @@ static int tile_hwtstamp_set(struct net_device *dev, struct ifreq *rq)
 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
+	case HWTSTAMP_FILTER_NTP_ALL:
 		config.rx_filter = HWTSTAMP_FILTER_ALL;
 		break;
 	default:
diff --git a/net/core/dev_ioctl.c b/net/core/dev_ioctl.c
index 8f036a7..77f04e7 100644
--- a/net/core/dev_ioctl.c
+++ b/net/core/dev_ioctl.c
@@ -225,9 +225,8 @@ static int net_hwtstamp_validate(struct ifreq *ifr)
 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
-		rx_filter_valid = 1;
-		break;
 	case HWTSTAMP_FILTER_NTP_ALL:
+		rx_filter_valid = 1;
 		break;
 	}
 
-- 
2.9.3

[PATCH v2 net-next 3/7] net: add function to retrieve original skb device using NAPI ID

[Miroslav Lichvar]

Since commit b68581778cd0 ("net: Make skb->skb_iif always track
skb->dev") skbs don't have the original index of the interface which
received the packet. This information is now needed for a new control
message related to hardware timestamping.

Instead of adding a new field to skb, we can find the device by the NAPI
ID if it is available, i.e. CONFIG_NET_RX_BUSY_POLL is enabled and the
driver is using NAPI. Add dev_get_by_napi_id() and also skb_napi_id() to
hide the CONFIG_NET_RX_BUSY_POLL ifdef.

CC: Richard Cochran <richardcochran@gmail.com>
CC: Willem de Bruijn <willemb@google.com>
Suggested-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
---
 include/linux/netdevice.h |  1 +
 include/linux/skbuff.h    |  9 +++++++++
 net/core/dev.c            | 26 ++++++++++++++++++++++++++
 3 files changed, 36 insertions(+)

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 9c23bd2..4ca2a16 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -2456,6 +2456,7 @@ static inline int dev_recursion_level(void)
 struct net_device *dev_get_by_index(struct net *net, int ifindex);
 struct net_device *__dev_get_by_index(struct net *net, int ifindex);
 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex);
+struct net_device *dev_get_by_napi_id(unsigned int napi_id);
 int netdev_get_name(struct net *net, char *name, int ifindex);
 int dev_restart(struct net_device *dev);
 int skb_gro_receive(struct sk_buff **head, struct sk_buff *skb);
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 81ef53f..bfe6ec3 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -915,6 +915,15 @@ static inline bool skb_pkt_type_ok(u32 ptype)
 	return ptype <= PACKET_OTHERHOST;
 }
 
+static inline unsigned int skb_napi_id(const struct sk_buff *skb)
+{
+#ifdef CONFIG_NET_RX_BUSY_POLL
+	return skb->napi_id;
+#else
+	return 0;
+#endif
+}
+
 void kfree_skb(struct sk_buff *skb);
 void kfree_skb_list(struct sk_buff *segs);
 void skb_tx_error(struct sk_buff *skb);
diff --git a/net/core/dev.c b/net/core/dev.c
index 35a06ce..fe079b2 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -160,6 +160,7 @@ static int netif_rx_internal(struct sk_buff *skb);
 static int call_netdevice_notifiers_info(unsigned long val,
 					 struct net_device *dev,
 					 struct netdev_notifier_info *info);
+static struct napi_struct *napi_by_id(unsigned int napi_id);
 
 /*
  * The @dev_base_head list is protected by @dev_base_lock and the rtnl
@@ -864,6 +865,31 @@ struct net_device *dev_get_by_index(struct net *net, int ifindex)
 EXPORT_SYMBOL(dev_get_by_index);
 
 /**
+ *	dev_get_by_napi_id - find a device by napi_id
+ *	@napi_id: ID of the NAPI struct
+ *
+ *	Search for an interface by NAPI ID. Returns %NULL if the device
+ *	is not found or a pointer to the device. The device has not had
+ *	its reference counter increased so the caller must be careful
+ *	about locking. The caller must hold RCU lock.
+ */
+
+struct net_device *dev_get_by_napi_id(unsigned int napi_id)
+{
+	struct napi_struct *napi;
+
+	if (napi_id < MIN_NAPI_ID)
+		return NULL;
+
+	napi = napi_by_id(napi_id);
+	if (napi)
+		return napi->dev;
+
+	return NULL;
+}
+EXPORT_SYMBOL(dev_get_by_napi_id);
+
+/**
  *	netdev_get_name - get a netdevice name, knowing its ifindex.
  *	@net: network namespace
  *	@name: a pointer to the buffer where the name will be stored.
-- 
2.9.3

[PATCH v2 net-next 4/7] net: add new control message for incoming HW-timestamped packets

[Miroslav Lichvar]

Add SOF_TIMESTAMPING_OPT_PKTINFO option to request a new control message
for incoming packets with hardware timestamps. It contains the index of
the real interface which received the packet and the length of the
packet at layer 2.

The index is useful with bonding, bridges and other interfaces, where
IP_PKTINFO doesn't allow applications to determine which PHC made the
timestamp. With the L2 length (and link speed) it is possible to
transpose preamble timestamps to trailer timestamps, which are used in
the NTP protocol.

While this information could be provided by two new socket options
independently from timestamping, it doesn't look like it would be very
useful. With this option any performance impact is limited to hardware
timestamping.

Use dev_get_by_napi_id() to look up the device and its index. This
limits the option to kernels with enabled CONFIG_NET_RX_BUSY_POLL and
drivers using napi, but it should cover all current MAC drivers that
support hardware timestamping.

CC: Richard Cochran <richardcochran@gmail.com>
CC: Willem de Bruijn <willemb@google.com>
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
---
 Documentation/networking/timestamping.txt |  8 ++++++++
 include/uapi/asm-generic/socket.h         |  2 ++
 include/uapi/linux/net_tstamp.h           |  9 ++++++++-
 net/socket.c                              | 30 +++++++++++++++++++++++++++++-
 4 files changed, 47 insertions(+), 2 deletions(-)

diff --git a/Documentation/networking/timestamping.txt b/Documentation/networking/timestamping.txt
index 96f5069..6c07e7c 100644
--- a/Documentation/networking/timestamping.txt
+++ b/Documentation/networking/timestamping.txt
@@ -193,6 +193,14 @@ SOF_TIMESTAMPING_OPT_STATS:
   the transmit timestamps, such as how long a certain block of
   data was limited by peer's receiver window.
 
+SOF_TIMESTAMPING_OPT_PKTINFO:
+
+  Enable the SCM_TIMESTAMPING_PKTINFO control message for incoming
+  packets with hardware timestamps. The message contains struct
+  scm_ts_pktinfo, which supplies the index of the real interface
+  which received the packet and its length at layer 2. This option
+  works only if CONFIG_NET_RX_BUSY_POLL is enabled.
+
 New applications are encouraged to pass SOF_TIMESTAMPING_OPT_ID to
 disambiguate timestamps and SOF_TIMESTAMPING_OPT_TSONLY to operate
 regardless of the setting of sysctl net.core.tstamp_allow_data.
diff --git a/include/uapi/asm-generic/socket.h b/include/uapi/asm-generic/socket.h
index 2b48856..a5f6e81 100644
--- a/include/uapi/asm-generic/socket.h
+++ b/include/uapi/asm-generic/socket.h
@@ -100,4 +100,6 @@
 
 #define SO_COOKIE		57
 
+#define SCM_TIMESTAMPING_PKTINFO	58
+
 #endif /* __ASM_GENERIC_SOCKET_H */
diff --git a/include/uapi/linux/net_tstamp.h b/include/uapi/linux/net_tstamp.h
index 0749fb1..8fcae35 100644
--- a/include/uapi/linux/net_tstamp.h
+++ b/include/uapi/linux/net_tstamp.h
@@ -26,8 +26,9 @@ enum {
 	SOF_TIMESTAMPING_OPT_CMSG = (1<<10),
 	SOF_TIMESTAMPING_OPT_TSONLY = (1<<11),
 	SOF_TIMESTAMPING_OPT_STATS = (1<<12),
+	SOF_TIMESTAMPING_OPT_PKTINFO = (1<<13),
 
-	SOF_TIMESTAMPING_LAST = SOF_TIMESTAMPING_OPT_STATS,
+	SOF_TIMESTAMPING_LAST = SOF_TIMESTAMPING_OPT_PKTINFO,
 	SOF_TIMESTAMPING_MASK = (SOF_TIMESTAMPING_LAST - 1) |
 				 SOF_TIMESTAMPING_LAST
 };
@@ -130,4 +131,10 @@ enum hwtstamp_rx_filters {
 	HWTSTAMP_FILTER_NTP_ALL,
 };
 
+/* SCM_TIMESTAMPING_PKTINFO control message */
+struct scm_ts_pktinfo {
+	int if_index;
+	int pkt_length;
+};
+
 #endif /* _NET_TIMESTAMPING_H */
diff --git a/net/socket.c b/net/socket.c
index c2564eb..da4d4ab 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -662,6 +662,30 @@ static bool skb_is_err_queue(const struct sk_buff *skb)
 	return skb->pkt_type == PACKET_OUTGOING;
 }
 
+static void put_ts_pktinfo(struct msghdr *msg, struct sk_buff *skb)
+{
+	struct scm_ts_pktinfo ts_pktinfo;
+	struct net_device *orig_dev;
+	int ifindex = 0;
+
+	if (!skb_mac_header_was_set(skb))
+		return;
+
+	rcu_read_lock();
+	orig_dev = dev_get_by_napi_id(skb_napi_id(skb));
+	if (orig_dev)
+		ifindex = orig_dev->ifindex;
+	rcu_read_unlock();
+
+	if (ifindex == 0)
+		return;
+
+	ts_pktinfo.if_index = ifindex;
+	ts_pktinfo.pkt_length = skb->len - skb_mac_offset(skb);
+	put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMPING_PKTINFO,
+		 sizeof(ts_pktinfo), &ts_pktinfo);
+}
+
 /*
  * called from sock_recv_timestamp() if sock_flag(sk, SOCK_RCVTSTAMP)
  */
@@ -699,8 +723,12 @@ void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
 		empty = 0;
 	if (shhwtstamps &&
 	    (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
-	    ktime_to_timespec_cond(shhwtstamps->hwtstamp, tss.ts + 2))
+	    ktime_to_timespec_cond(shhwtstamps->hwtstamp, tss.ts + 2)) {
 		empty = 0;
+		if ((sk->sk_tsflags & SOF_TIMESTAMPING_OPT_PKTINFO) &&
+		    !skb_is_err_queue(skb))
+			put_ts_pktinfo(msg, skb);
+	}
 	if (!empty) {
 		put_cmsg(msg, SOL_SOCKET,
 			 SCM_TIMESTAMPING, sizeof(tss), &tss);
-- 
2.9.3

[PATCH v2 net-next 5/7] net: don't make false software transmit timestamps

[Miroslav Lichvar]

If software timestamping is enabled by the SO_TIMESTAMP(NS) option
when a message without timestamp is already waiting in the queue, the
__sock_recv_timestamp() function will read the current time to make a
timestamp in order to always have something for the application.

However, this applies also to outgoing packets looped back to the error
queue when hardware timestamping is enabled by the SO_TIMESTAMPING
option. A software transmit timestamp made after the actual transmission
is added to messages with hardware timestamps.

Modify the function to save the current time as a software timestamp
only if it's for a received packet (i.e. it's not in the error queue).

CC: Richard Cochran <richardcochran@gmail.com>
CC: Willem de Bruijn <willemb@google.com>
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
---
 net/socket.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/socket.c b/net/socket.c
index da4d4ab..fe7e5bc 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -692,7 +692,8 @@ static void put_ts_pktinfo(struct msghdr *msg, struct sk_buff *skb)
 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
 	struct sk_buff *skb)
 {
-	int need_software_tstamp = sock_flag(sk, SOCK_RCVTSTAMP);
+	int need_software_tstamp = sock_flag(sk, SOCK_RCVTSTAMP) &&
+				   !skb_is_err_queue(skb);
 	struct scm_timestamping tss;
 	int empty = 1;
 	struct skb_shared_hwtstamps *shhwtstamps =
-- 
2.9.3

[PATCH v2 net-next 6/7] net: allow simultaneous SW and HW transmit timestamping

[Miroslav Lichvar]

Add SOF_TIMESTAMPING_OPT_TX_SWHW option to allow an outgoing packet to
be looped to the socket's error queue with a software timestamp even
when a hardware transmit timestamp is expected to be provided by the
driver.

Applications using this option will receive two separate messages from
the error queue, one with a software timestamp and the other with a
hardware timestamp. As the hardware timestamp is saved to the shared skb
info, which may happen before the first message with software timestamp
is received by the application, the hardware timestamp is copied to the
SCM_TIMESTAMPING control message only when the skb has no software
timestamp or it is an incoming packet.

While changing sw_tx_timestamp(), inline it in skb_tx_timestamp() as
there are no other users.

CC: Richard Cochran <richardcochran@gmail.com>
CC: Willem de Bruijn <willemb@google.com>
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
---
 Documentation/networking/timestamping.txt | 14 ++++++++++++--
 include/linux/skbuff.h                    | 10 ++--------
 include/uapi/linux/net_tstamp.h           |  3 ++-
 net/core/skbuff.c                         |  4 ++++
 net/socket.c                              | 11 +++++++++++
 5 files changed, 31 insertions(+), 11 deletions(-)

diff --git a/Documentation/networking/timestamping.txt b/Documentation/networking/timestamping.txt
index 6c07e7c..ab29a6e 100644
--- a/Documentation/networking/timestamping.txt
+++ b/Documentation/networking/timestamping.txt
@@ -201,6 +201,14 @@ SOF_TIMESTAMPING_OPT_PKTINFO:
   which received the packet and its length at layer 2. This option
   works only if CONFIG_NET_RX_BUSY_POLL is enabled.
 
+SOF_TIMESTAMPING_OPT_TX_SWHW:
+
+  Request both hardware and software timestamps for outgoing packets
+  when SOF_TIMESTAMPING_TX_HARDWARE and SOF_TIMESTAMPING_TX_SOFTWARE
+  are enabled at the same time. If both timestamps are generated,
+  two separate messages will be looped to the socket's error queue,
+  each containing just one timestamp.
+
 New applications are encouraged to pass SOF_TIMESTAMPING_OPT_ID to
 disambiguate timestamps and SOF_TIMESTAMPING_OPT_TSONLY to operate
 regardless of the setting of sysctl net.core.tstamp_allow_data.
@@ -320,8 +328,10 @@ struct scm_timestamping {
 };
 
 The structure can return up to three timestamps. This is a legacy
-feature. Only one field is non-zero at any time. Most timestamps
-are passed in ts[0]. Hardware timestamps are passed in ts[2].
+feature. Most timestamps are passed in ts[0]. Hardware timestamps
+are passed in ts[2]. Incoming packets may have timestamps in both
+ts[0] and ts[2], but for outgoing packets only one field is non-zero
+at any time.
 
 ts[1] used to hold hardware timestamps converted to system time.
 Instead, expose the hardware clock device on the NIC directly as
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index bfe6ec3..3be2241 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -3307,13 +3307,6 @@ void __skb_tstamp_tx(struct sk_buff *orig_skb,
 void skb_tstamp_tx(struct sk_buff *orig_skb,
 		   struct skb_shared_hwtstamps *hwtstamps);
 
-static inline void sw_tx_timestamp(struct sk_buff *skb)
-{
-	if (skb_shinfo(skb)->tx_flags & SKBTX_SW_TSTAMP &&
-	    !(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS))
-		skb_tstamp_tx(skb, NULL);
-}
-
 /**
  * skb_tx_timestamp() - Driver hook for transmit timestamping
  *
@@ -3329,7 +3322,8 @@ static inline void sw_tx_timestamp(struct sk_buff *skb)
 static inline void skb_tx_timestamp(struct sk_buff *skb)
 {
 	skb_clone_tx_timestamp(skb);
-	sw_tx_timestamp(skb);
+	if (skb_shinfo(skb)->tx_flags & SKBTX_SW_TSTAMP)
+		skb_tstamp_tx(skb, NULL);
 }
 
 /**
diff --git a/include/uapi/linux/net_tstamp.h b/include/uapi/linux/net_tstamp.h
index 8fcae35..d251972 100644
--- a/include/uapi/linux/net_tstamp.h
+++ b/include/uapi/linux/net_tstamp.h
@@ -27,8 +27,9 @@ enum {
 	SOF_TIMESTAMPING_OPT_TSONLY = (1<<11),
 	SOF_TIMESTAMPING_OPT_STATS = (1<<12),
 	SOF_TIMESTAMPING_OPT_PKTINFO = (1<<13),
+	SOF_TIMESTAMPING_OPT_TX_SWHW = (1<<14),
 
-	SOF_TIMESTAMPING_LAST = SOF_TIMESTAMPING_OPT_PKTINFO,
+	SOF_TIMESTAMPING_LAST = SOF_TIMESTAMPING_OPT_TX_SWHW,
 	SOF_TIMESTAMPING_MASK = (SOF_TIMESTAMPING_LAST - 1) |
 				 SOF_TIMESTAMPING_LAST
 };
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 58604c1..db5aa19 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -3874,6 +3874,10 @@ void __skb_tstamp_tx(struct sk_buff *orig_skb,
 	if (!sk)
 		return;
 
+	if (!hwtstamps && !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_TX_SWHW) &&
+	    skb_shinfo(orig_skb)->tx_flags & SKBTX_IN_PROGRESS)
+		return;
+
 	tsonly = sk->sk_tsflags & SOF_TIMESTAMPING_OPT_TSONLY;
 	if (!skb_may_tx_timestamp(sk, tsonly))
 		return;
diff --git a/net/socket.c b/net/socket.c
index fe7e5bc..33827c4 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -662,6 +662,16 @@ static bool skb_is_err_queue(const struct sk_buff *skb)
 	return skb->pkt_type == PACKET_OUTGOING;
 }
 
+/* On transmit, software and hardware timestamps are returned independently.
+ * As the two skb clones share the hardware timestamp, which may be updated
+ * before the software timestamp is received, a hardware TX timestamp may be
+ * returned only if there is no software TX timestamp.
+ */
+static bool skb_is_swtx_tstamp(const struct sk_buff *skb)
+{
+	return skb->tstamp && skb_is_err_queue(skb);
+}
+
 static void put_ts_pktinfo(struct msghdr *msg, struct sk_buff *skb)
 {
 	struct scm_ts_pktinfo ts_pktinfo;
@@ -724,6 +734,7 @@ void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
 		empty = 0;
 	if (shhwtstamps &&
 	    (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
+	    !skb_is_swtx_tstamp(skb) &&
 	    ktime_to_timespec_cond(shhwtstamps->hwtstamp, tss.ts + 2)) {
 		empty = 0;
 		if ((sk->sk_tsflags & SOF_TIMESTAMPING_OPT_PKTINFO) &&
-- 
2.9.3

[PATCH v2 net-next 7/7] net: ethernet: update drivers to make both SW and HW TX timestamps

[Miroslav Lichvar]

Some drivers were calling the skb_tx_timestamp() function only when
a hardware timestamp was not requested. Now that applications can use
the SOF_TIMESTAMPING_OPT_TX_SWHW option to request both software and
hardware timestamps, the drivers need to be modified to unconditionally
call skb_tx_timestamp().

CC: Richard Cochran <richardcochran@gmail.com>
CC: Willem de Bruijn <willemb@google.com>
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
---
 drivers/net/ethernet/amd/xgbe/xgbe-drv.c          | 3 +--
 drivers/net/ethernet/intel/e1000e/netdev.c        | 4 ++--
 drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c   | 3 +--
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 6 ++----
 4 files changed, 6 insertions(+), 10 deletions(-)

diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-drv.c b/drivers/net/ethernet/amd/xgbe/xgbe-drv.c
index 89b21d7..5a2ad9c 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe-drv.c
+++ b/drivers/net/ethernet/amd/xgbe/xgbe-drv.c
@@ -1391,8 +1391,7 @@ static void xgbe_prep_tx_tstamp(struct xgbe_prv_data *pdata,
 		spin_unlock_irqrestore(&pdata->tstamp_lock, flags);
 	}
 
-	if (!XGMAC_GET_BITS(packet->attributes, TX_PACKET_ATTRIBUTES, PTP))
-		skb_tx_timestamp(skb);
+	skb_tx_timestamp(skb);
 }
 
 static void xgbe_prep_vlan(struct sk_buff *skb, struct xgbe_packet_data *packet)
diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c
index 0ff9295..6ed3bc4 100644
--- a/drivers/net/ethernet/intel/e1000e/netdev.c
+++ b/drivers/net/ethernet/intel/e1000e/netdev.c
@@ -5868,10 +5868,10 @@ static netdev_tx_t e1000_xmit_frame(struct sk_buff *skb,
 			adapter->tx_hwtstamp_skb = skb_get(skb);
 			adapter->tx_hwtstamp_start = jiffies;
 			schedule_work(&adapter->tx_hwtstamp_work);
-		} else {
-			skb_tx_timestamp(skb);
 		}
 
+		skb_tx_timestamp(skb);
+
 		netdev_sent_queue(netdev, skb->len);
 		e1000_tx_queue(tx_ring, tx_flags, count);
 		/* Make sure there is space in the ring for the next send. */
diff --git a/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c b/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
index d54490d..50c182c 100644
--- a/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
+++ b/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
@@ -1418,8 +1418,7 @@ static netdev_tx_t sxgbe_xmit(struct sk_buff *skb, struct net_device *dev)
 		priv->hw->desc->tx_enable_tstamp(first_desc);
 	}
 
-	if (!tqueue->hwts_tx_en)
-		skb_tx_timestamp(skb);
+	skb_tx_timestamp(skb);
 
 	priv->hw->dma->enable_dma_transmission(priv->ioaddr, txq_index);
 
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 3115700..7f857ee 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -2880,8 +2880,7 @@ static netdev_tx_t stmmac_tso_xmit(struct sk_buff *skb, struct net_device *dev)
 		priv->xstats.tx_set_ic_bit++;
 	}
 
-	if (!priv->hwts_tx_en)
-		skb_tx_timestamp(skb);
+	skb_tx_timestamp(skb);
 
 	if (unlikely((skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP) &&
 		     priv->hwts_tx_en)) {
@@ -3084,8 +3083,7 @@ static netdev_tx_t stmmac_xmit(struct sk_buff *skb, struct net_device *dev)
 		priv->xstats.tx_set_ic_bit++;
 	}
 
-	if (!priv->hwts_tx_en)
-		skb_tx_timestamp(skb);
+	skb_tx_timestamp(skb);
 
 	/* Ready to fill the first descriptor and set the OWN bit w/o any
 	 * problems because all the descriptors are actually ready to be
-- 
2.9.3

Re: [PATCH v2 net-next 0/7] Extend socket timestamping API

[Miroslav Lichvar]

Hm, I see that net-next was closed. I missed the annoucement. Sorry
for the spam.

On Tue, May 02, 2017 at 02:46:02PM +0200, Miroslav Lichvar wrote:
> Changes v1->v2:
> - added separate patch for new NAPI functions 
> - split code from __sock_recv_timestamp() for better readability
> - fixed RCU locking
> - fixed compiler warning (missing case in switch in first patch)
> - inline sw_tx_timestamp() in its only user

-- 
Miroslav Lichvar

Re: [PATCH v2 net-next 4/7] net: add new control message for incoming HW-timestamped packets

[Willem de Bruijn]

On Tue, May 2, 2017 at 6:11 AM, Miroslav Lichvar <mlichvar@redhat.com> wrote:
> Add SOF_TIMESTAMPING_OPT_PKTINFO option to request a new control message
> for incoming packets with hardware timestamps. It contains the index of
> the real interface which received the packet and the length of the
> packet at layer 2.
>
> The index is useful with bonding, bridges and other interfaces, where
> IP_PKTINFO doesn't allow applications to determine which PHC made the
> timestamp. With the L2 length (and link speed) it is possible to
> transpose preamble timestamps to trailer timestamps, which are used in
> the NTP protocol.
>
> While this information could be provided by two new socket options
> independently from timestamping, it doesn't look like it would be very
> useful. With this option any performance impact is limited to hardware
> timestamping.
>
> Use dev_get_by_napi_id() to look up the device and its index. This
> limits the option to kernels with enabled CONFIG_NET_RX_BUSY_POLL and
> drivers using napi, but it should cover all current MAC drivers that
> support hardware timestamping.
>
> CC: Richard Cochran <richardcochran@gmail.com>
> CC: Willem de Bruijn <willemb@google.com>
> Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
> ---
>  Documentation/networking/timestamping.txt |  8 ++++++++
>  include/uapi/asm-generic/socket.h         |  2 ++
>  include/uapi/linux/net_tstamp.h           |  9 ++++++++-
>  net/socket.c                              | 30 +++++++++++++++++++++++++++++-
>  4 files changed, 47 insertions(+), 2 deletions(-)
>
> diff --git a/Documentation/networking/timestamping.txt b/Documentation/networking/timestamping.txt
> index 96f5069..6c07e7c 100644
> --- a/Documentation/networking/timestamping.txt
> +++ b/Documentation/networking/timestamping.txt
> @@ -193,6 +193,14 @@ SOF_TIMESTAMPING_OPT_STATS:
>    the transmit timestamps, such as how long a certain block of
>    data was limited by peer's receiver window.
>
> +SOF_TIMESTAMPING_OPT_PKTINFO:
> +
> +  Enable the SCM_TIMESTAMPING_PKTINFO control message for incoming
> +  packets with hardware timestamps. The message contains struct
> +  scm_ts_pktinfo, which supplies the index of the real interface
> +  which received the packet and its length at layer 2. This option
> +  works only if CONFIG_NET_RX_BUSY_POLL is enabled.
> +
>  New applications are encouraged to pass SOF_TIMESTAMPING_OPT_ID to
>  disambiguate timestamps and SOF_TIMESTAMPING_OPT_TSONLY to operate
>  regardless of the setting of sysctl net.core.tstamp_allow_data.
> diff --git a/include/uapi/asm-generic/socket.h b/include/uapi/asm-generic/socket.h
> index 2b48856..a5f6e81 100644
> --- a/include/uapi/asm-generic/socket.h
> +++ b/include/uapi/asm-generic/socket.h
> @@ -100,4 +100,6 @@
>
>  #define SO_COOKIE              57
>
> +#define SCM_TIMESTAMPING_PKTINFO       58
> +
>  #endif /* __ASM_GENERIC_SOCKET_H */
> diff --git a/include/uapi/linux/net_tstamp.h b/include/uapi/linux/net_tstamp.h
> index 0749fb1..8fcae35 100644
> --- a/include/uapi/linux/net_tstamp.h
> +++ b/include/uapi/linux/net_tstamp.h
> @@ -26,8 +26,9 @@ enum {
>         SOF_TIMESTAMPING_OPT_CMSG = (1<<10),
>         SOF_TIMESTAMPING_OPT_TSONLY = (1<<11),
>         SOF_TIMESTAMPING_OPT_STATS = (1<<12),
> +       SOF_TIMESTAMPING_OPT_PKTINFO = (1<<13),
>
> -       SOF_TIMESTAMPING_LAST = SOF_TIMESTAMPING_OPT_STATS,
> +       SOF_TIMESTAMPING_LAST = SOF_TIMESTAMPING_OPT_PKTINFO,
>         SOF_TIMESTAMPING_MASK = (SOF_TIMESTAMPING_LAST - 1) |
>                                  SOF_TIMESTAMPING_LAST
>  };
> @@ -130,4 +131,10 @@ enum hwtstamp_rx_filters {
>         HWTSTAMP_FILTER_NTP_ALL,
>  };
>
> +/* SCM_TIMESTAMPING_PKTINFO control message */
> +struct scm_ts_pktinfo {
> +       int if_index;
> +       int pkt_length;
> +};

Use fixed width integer types across the ABI.

> +static void put_ts_pktinfo(struct msghdr *msg, struct sk_buff *skb)
> +{
> +       struct scm_ts_pktinfo ts_pktinfo;
> +       struct net_device *orig_dev;
> +       int ifindex = 0;
> +
> +       if (!skb_mac_header_was_set(skb))
> +               return;
> +
> +       rcu_read_lock();
> +       orig_dev = dev_get_by_napi_id(skb_napi_id(skb));
> +       if (orig_dev)
> +               ifindex = orig_dev->ifindex;
> +       rcu_read_unlock();
> +
> +       if (ifindex == 0)
> +               return;

If the caller requests PKTINFO, it might be better to explicitly return
a structure with illegal value 0, than to silently skip the message if
no device can be found.

Re: [PATCH v2 net-next 3/7] net: add function to retrieve original skb device using NAPI ID

[Willem de Bruijn]

On Tue, May 2, 2017 at 6:10 AM, Miroslav Lichvar <mlichvar@redhat.com> wrote:
> Since commit b68581778cd0 ("net: Make skb->skb_iif always track
> skb->dev") skbs don't have the original index of the interface which
> received the packet. This information is now needed for a new control
> message related to hardware timestamping.
>
> Instead of adding a new field to skb, we can find the device by the NAPI
> ID if it is available, i.e. CONFIG_NET_RX_BUSY_POLL is enabled and the
> driver is using NAPI. Add dev_get_by_napi_id() and also skb_napi_id() to
> hide the CONFIG_NET_RX_BUSY_POLL ifdef.
>
> CC: Richard Cochran <richardcochran@gmail.com>
> CC: Willem de Bruijn <willemb@google.com>
> Suggested-by: Willem de Bruijn <willemb@google.com>
> Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>

>  /**
> + *     dev_get_by_napi_id - find a device by napi_id
> + *     @napi_id: ID of the NAPI struct
> + *
> + *     Search for an interface by NAPI ID. Returns %NULL if the device
> + *     is not found or a pointer to the device. The device has not had
> + *     its reference counter increased so the caller must be careful
> + *     about locking. The caller must hold RCU lock.

Instead of a comment, can check with

  WARN_ON_ONCE(!rcu_read_lock_held());

> + */
> +
> +struct net_device *dev_get_by_napi_id(unsigned int napi_id)
> +{
> +       struct napi_struct *napi;
> +
> +       if (napi_id < MIN_NAPI_ID)
> +               return NULL;
> +
> +       napi = napi_by_id(napi_id);
> +       if (napi)
> +               return napi->dev;
> +
> +       return NULL;

make return NULL the branch expected not taken.

  return napi ? napi->dev : NULL;

Re: [PATCH v2 net-next 4/7] net: add new control message for incoming HW-timestamped packets

[kbuild test robot]

[-- Attachment #1: Type: text/plain, Size: 1380 bytes --]

Hi Miroslav,

[auto build test ERROR on net-next/master]

url:    https://github.com/0day-ci/linux/commits/Miroslav-Lichvar/Extend-socket-timestamping-API/20170502-212515
config: xtensa-allmodconfig (attached as .config)
compiler: xtensa-linux-gcc (GCC) 4.9.0
reproduce:
        wget https://raw.githubusercontent.com/01org/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=xtensa 

All errors (new ones prefixed by >>):

   net/socket.c: In function 'put_ts_pktinfo':
>> net/socket.c:685:28: error: 'SCM_TIMESTAMPING_PKTINFO' undeclared (first use in this function)
     put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMPING_PKTINFO,
                               ^
   net/socket.c:685:28: note: each undeclared identifier is reported only once for each function it appears in

vim +/SCM_TIMESTAMPING_PKTINFO +685 net/socket.c

   679	
   680		if (ifindex == 0)
   681			return;
   682	
   683		ts_pktinfo.if_index = ifindex;
   684		ts_pktinfo.pkt_length = skb->len - skb_mac_offset(skb);
 > 685		put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMPING_PKTINFO,
   686			 sizeof(ts_pktinfo), &ts_pktinfo);
   687	}
   688	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 49232 bytes --]

Re: [PATCH v2 net-next 3/7] net: add function to retrieve original skb device using NAPI ID

[Miroslav Lichvar]

On Tue, May 02, 2017 at 12:16:13PM -0400, Willem de Bruijn wrote:
> On Tue, May 2, 2017 at 6:10 AM, Miroslav Lichvar <mlichvar@redhat.com> wrote:
> >  /**
> > + *     dev_get_by_napi_id - find a device by napi_id
> > + *     @napi_id: ID of the NAPI struct
> > + *
> > + *     Search for an interface by NAPI ID. Returns %NULL if the device
> > + *     is not found or a pointer to the device. The device has not had
> > + *     its reference counter increased so the caller must be careful
> > + *     about locking. The caller must hold RCU lock.
> 
> Instead of a comment, can check with
> 
>   WARN_ON_ONCE(!rcu_read_lock_held());

The other dev_get_* functions have the same comment, so I think it's
better to keep it for consistency. I'll add the warning and sent
a new series with the other changes you have suggested.

Thanks,

-- 
Miroslav Lichvar