[PATCH v4 net-next 0/7] Extend socket timestamping API

[PATCH v4 net-next 0/7] Extend socket timestamping API

[Miroslav Lichvar]

Changes v3->v4:
- added reserved fields to struct scm_ts_pktinfo
- replaced patch fixing false SW timestamps with a documentation fix
- updated OPT_TX_SWHW patch to handle false SW timestamps

Changes v2->v3:
- modified struct scm_ts_pktinfo to use fixed-width integer types
- added WARN_ON_ONCE for missing RCU lock in dev_get_by_napi_id()
- modified dev_get_by_napi_id() to not return dev in unexpected branch
- modified recv to return SCM_TIMESTAMPING_PKTINFO even if the interface
  index is unknown

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 documentation on number of non-zero fields in
scm_timestamping and warns about false software timestamps when
SO_TIMESTAMP(NS) is combined with SCM_TIMESTAMPING.

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: fix documentation of struct scm_timestamping
  net: allow simultaneous SW and HW transmit timestamping
  net: ethernet: update drivers to make both SW and HW TX timestamps

 Documentation/networking/timestamping.txt          | 25 ++++++++++-
 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                    | 15 ++++++-
 net/core/dev.c                                     | 26 +++++++++++
 net/core/dev_ioctl.c                               |  1 +
 net/core/skbuff.c                                  |  4 ++
 net/socket.c                                       | 50 ++++++++++++++++++++--
 27 files changed, 153 insertions(+), 23 deletions(-)

-- 
2.9.3

[PATCH v4 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 v4 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 7414ffd..14c236e 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 649f2aa..ba01242 100644
--- a/drivers/net/ethernet/cavium/liquidio/lio_main.c
+++ b/drivers/net/ethernet/cavium/liquidio/lio_main.c
@@ -3024,6 +3024,7 @@ 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 d51c8d8..31d737c 100644
--- a/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c
+++ b/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c
@@ -2085,6 +2085,7 @@ 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 24f06e2..9b2280b 100644
--- a/drivers/net/ethernet/qlogic/qede/qede_ptp.c
+++ b/drivers/net/ethernet/qlogic/qede/qede_ptp.c
@@ -244,6 +244,7 @@ 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;
 		rx_filter = QED_PTP_FILTER_ALL;
 		break;
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 a74c481..cce862b 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 f4d7aec..37fc165 100644
--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -1734,6 +1734,7 @@ 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 v4 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>
Suggested-by: Willem de Bruijn <willemb@google.com>
Acked-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 3f39d27..b6c36d5 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 7c0cb2c..1f8028c 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -855,6 +855,15 @@ 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 acd594c..6d3c452 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -162,6 +162,7 @@ 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
@@ -866,6 +867,31 @@ 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;
+
+	WARN_ON_ONCE(!rcu_read_lock_held());
+
+	if (napi_id < MIN_NAPI_ID)
+		return NULL;
+
+	napi = napi_by_id(napi_id);
+
+	return napi ? napi->dev : 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 v4 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 they would be very
useful. With this option any performance impact is limited to hardware
timestamping.

Use dev_get_by_napi_id() to get the device and its index. On kernels
with disabled CONFIG_NET_RX_BUSY_POLL or drivers not using NAPI, a zero
index will be returned in the control message.

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 |  9 +++++++++
 include/uapi/asm-generic/socket.h         |  2 ++
 include/uapi/linux/net_tstamp.h           | 11 ++++++++++-
 net/socket.c                              | 27 ++++++++++++++++++++++++++-
 4 files changed, 47 insertions(+), 2 deletions(-)

diff --git a/Documentation/networking/timestamping.txt b/Documentation/networking/timestamping.txt
index 96f5069..600c6bf 100644
--- a/Documentation/networking/timestamping.txt
+++ b/Documentation/networking/timestamping.txt
@@ -193,6 +193,15 @@ 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. A valid (non-zero)
+  interface index will be returned only if CONFIG_NET_RX_BUSY_POLL is
+  enabled and the driver is using NAPI.
+
 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..dee74d3 100644
--- a/include/uapi/linux/net_tstamp.h
+++ b/include/uapi/linux/net_tstamp.h
@@ -9,6 +9,7 @@
 #ifndef _NET_TIMESTAMPING_H
 #define _NET_TIMESTAMPING_H
 
+#include <linux/types.h>
 #include <linux/socket.h>   /* for SO_TIMESTAMPING */
 
 /* SO_TIMESTAMPING gets an integer bit field comprised of these values */
@@ -26,8 +27,9 @@ 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 +132,11 @@ enum hwtstamp_rx_filters {
 	HWTSTAMP_FILTER_NTP_ALL,
 };
 
+/* SCM_TIMESTAMPING_PKTINFO control message */
+struct scm_ts_pktinfo {
+	__u32 if_index;
+	__u32 pkt_length;
+	__u32 reserved[2];
+};
+
 #endif /* _NET_TIMESTAMPING_H */
diff --git a/net/socket.c b/net/socket.c
index c2564eb..ee1f4ec 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -662,6 +662,27 @@ 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();
+
+	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 +720,12 @@ 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 v4 net-next 5/7] net: fix documentation of struct scm_timestamping

[Miroslav Lichvar]

The scm_timestamping struct may return multiple non-zero fields, e.g.
when both software and hardware RX timestamping is enabled, or when the
SO_TIMESTAMP(NS) option is combined with SCM_TIMESTAMPING and a false
software timestamp is generated in the recvmsg() call in order to always
return a SCM_TIMESTAMP(NS) message.

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 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/Documentation/networking/timestamping.txt b/Documentation/networking/timestamping.txt
index 600c6bf..74b7c61 100644
--- a/Documentation/networking/timestamping.txt
+++ b/Documentation/networking/timestamping.txt
@@ -321,7 +321,7 @@ 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
+feature. At least one field is non-zero at any time. Most timestamps
 are passed in ts[0]. Hardware timestamps are passed in ts[2].
 
 ts[1] used to hold hardware timestamps converted to system time.
@@ -330,6 +330,12 @@ a HW PTP clock source, to allow time conversion in userspace and
 optionally synchronize system time with a userspace PTP stack such
 as linuxptp. For the PTP clock API, see Documentation/ptp/ptp.txt.
 
+Note that if the SO_TIMESTAMP or SO_TIMESTAMPNS option is enabled
+together with SO_TIMESTAMPING using SOF_TIMESTAMPING_SOFTWARE, a false
+software timestamp will be generated in the recvmsg() call and passed
+in ts[0] when a real software timestamp is missing. For this reason it
+is not recommended to combine SO_TIMESTAMP(NS) with SO_TIMESTAMPING.
+
 2.1.1 Transmit timestamps with MSG_ERRQUEUE
 
 For transmit timestamps the outgoing packet is looped back to the
-- 
2.9.3

[PATCH v4 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 |  8 ++++++++
 include/linux/skbuff.h                    | 10 ++--------
 include/uapi/linux/net_tstamp.h           |  3 ++-
 net/core/skbuff.c                         |  4 ++++
 net/socket.c                              | 23 +++++++++++++++++++++--
 5 files changed, 37 insertions(+), 11 deletions(-)

diff --git a/Documentation/networking/timestamping.txt b/Documentation/networking/timestamping.txt
index 74b7c61..65be2d9 100644
--- a/Documentation/networking/timestamping.txt
+++ b/Documentation/networking/timestamping.txt
@@ -202,6 +202,14 @@ SOF_TIMESTAMPING_OPT_PKTINFO:
   interface index will be returned only if CONFIG_NET_RX_BUSY_POLL is
   enabled and the driver is using NAPI.
 
+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.
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 1f8028c..3b2e284 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -3254,13 +3254,6 @@ 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
  *
@@ -3276,7 +3269,8 @@ 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 dee74d3..3d421d9 100644
--- a/include/uapi/linux/net_tstamp.h
+++ b/include/uapi/linux/net_tstamp.h
@@ -28,8 +28,9 @@ 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 346d3e8..68c02df 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -3875,6 +3875,10 @@ 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 ee1f4ec..64705ae 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -662,6 +662,22 @@ 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. A false software
+ * timestamp made for SOCK_RCVTSTAMP when a real timestamp is missing must
+ * be ignored.
+ */
+static bool skb_is_swtx_tstamp(const struct sk_buff *skb,
+			       const struct sock *sk, int false_tstamp)
+{
+	if (false_tstamp && sk->sk_tsflags & SOF_TIMESTAMPING_OPT_TX_SWHW)
+		return 0;
+
+	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;
@@ -691,14 +707,16 @@ void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
 {
 	int need_software_tstamp = sock_flag(sk, SOCK_RCVTSTAMP);
 	struct scm_timestamping tss;
-	int empty = 1;
+	int empty = 1, false_tstamp = 0;
 	struct skb_shared_hwtstamps *shhwtstamps =
 		skb_hwtstamps(skb);
 
 	/* Race occurred between timestamp enabling and packet
 	   receiving.  Fill in the current time for now. */
-	if (need_software_tstamp && skb->tstamp == 0)
+	if (need_software_tstamp && skb->tstamp == 0) {
 		__net_timestamp(skb);
+		false_tstamp = 1;
+	}
 
 	if (need_software_tstamp) {
 		if (!sock_flag(sk, SOCK_RCVTSTAMPNS)) {
@@ -720,6 +738,7 @@ 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, sk, false_tstamp) &&
 	    ktime_to_timespec_cond(shhwtstamps->hwtstamp, tss.ts + 2)) {
 		empty = 0;
 		if ((sk->sk_tsflags & SOF_TIMESTAMPING_OPT_PKTINFO) &&
-- 
2.9.3

[PATCH v4 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 1e59435..89831ad 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 cce862b..27c12e7 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 v4 net-next 0/7] Extend socket timestamping API

[Miroslav Lichvar]

On Thu, May 18, 2017 at 02:58:23PM +0200, Miroslav Lichvar wrote:
> Changes v3->v4:
> - added reserved fields to struct scm_ts_pktinfo

Of course, I forgot to initialize the new reserved fields. I'll send a
new series.

-- 
Miroslav Lichvar

Re: [PATCH v4 net-next 6/7] net: allow simultaneous SW and HW transmit timestamping

[Willem de Bruijn]

On Thu, May 18, 2017 at 9:06 AM, Miroslav Lichvar <mlichvar@redhat.com> wrote:
> 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>
> ---

> +/* 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. A false software
> + * timestamp made for SOCK_RCVTSTAMP when a real timestamp is missing must
> + * be ignored.

Please expand on why this case can be ignored. It is quite subtle. How about
something like

*
* A false software timestamp is one made inside the __sock_recv_timestamp
* call itself. These are generated whenever SO_TIMESTAMP(NS) is enabled
* on the socket, even when the timestamp reported is for another option, such
* as hardware tx timestamp.
*
* Ignore these when deciding whether a timestamp source is hw or sw.
*/

And perhaps move the comment to the branch itself.

> + */
> +static bool skb_is_swtx_tstamp(const struct sk_buff *skb,
> +                              const struct sock *sk, int false_tstamp)
> +{
> +       if (false_tstamp && sk->sk_tsflags & SOF_TIMESTAMPING_OPT_TX_SWHW)

Also, why is it ignored only for the new mode?

> +               return 0;
> +
> +       return skb->tstamp && skb_is_err_queue(skb);
> +}

Re: [PATCH v4 net-next 6/7] net: allow simultaneous SW and HW transmit timestamping

[Miroslav Lichvar]

On Thu, May 18, 2017 at 04:16:26PM -0400, Willem de Bruijn wrote:
> On Thu, May 18, 2017 at 9:06 AM, Miroslav Lichvar <mlichvar@redhat.com> wrote:
> > +/* 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. A false software
> > + * timestamp made for SOCK_RCVTSTAMP when a real timestamp is missing must
> > + * be ignored.
> 
> Please expand on why this case can be ignored. It is quite subtle. How about
> something like
> 
> *
> * A false software timestamp is one made inside the __sock_recv_timestamp
> * call itself. These are generated whenever SO_TIMESTAMP(NS) is enabled
> * on the socket, even when the timestamp reported is for another option, such
> * as hardware tx timestamp.
> *
> * Ignore these when deciding whether a timestamp source is hw or sw.
> */

That seems a bit too verbose to me. :) Would the following work?

/* 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. Ignore false software
 * timestamps, which may be made in the __sock_recv_timestamp() call when the
 * option SO_TIMESTAMP(NS) is enabled on the socket, even when the skb has a
 * hardware timestamp.
 */

> > +static bool skb_is_swtx_tstamp(const struct sk_buff *skb,
> > +                              const struct sock *sk, int false_tstamp)
> > +{
> > +       if (false_tstamp && sk->sk_tsflags & SOF_TIMESTAMPING_OPT_TX_SWHW)
> 
> Also, why is it ignored only for the new mode?

Good point. That should not be there. The function can be now reduced
to a single line again. I originally tried a different approach,
disabling false timestamps in the new mode, but then I thought it's
better to not complicate it unnecessarily and keep it consistent.

-- 
Miroslav Lichvar

Re: [PATCH v4 net-next 6/7] net: allow simultaneous SW and HW transmit timestamping

[Willem de Bruijn]

On Fri, May 19, 2017 at 6:00 AM, Miroslav Lichvar <mlichvar@redhat.com> wrote:
> On Thu, May 18, 2017 at 04:16:26PM -0400, Willem de Bruijn wrote:
>> On Thu, May 18, 2017 at 9:06 AM, Miroslav Lichvar <mlichvar@redhat.com> wrote:
>> > +/* 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. A false software
>> > + * timestamp made for SOCK_RCVTSTAMP when a real timestamp is missing must
>> > + * be ignored.
>>
>> Please expand on why this case can be ignored. It is quite subtle. How about
>> something like
>>
>> *
>> * A false software timestamp is one made inside the __sock_recv_timestamp
>> * call itself. These are generated whenever SO_TIMESTAMP(NS) is enabled
>> * on the socket, even when the timestamp reported is for another option, such
>> * as hardware tx timestamp.
>> *
>> * Ignore these when deciding whether a timestamp source is hw or sw.
>> */
>
> That seems a bit too verbose to me. :) Would the following work?
>
> /* 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. Ignore false software
>  * timestamps, which may be made in the __sock_recv_timestamp() call when the
>  * option SO_TIMESTAMP(NS) is enabled on the socket, even when the skb has a
>  * hardware timestamp.
>  */

Looks great, thanks.

>
>> > +static bool skb_is_swtx_tstamp(const struct sk_buff *skb,
>> > +                              const struct sock *sk, int false_tstamp)
>> > +{
>> > +       if (false_tstamp && sk->sk_tsflags & SOF_TIMESTAMPING_OPT_TX_SWHW)
>>
>> Also, why is it ignored only for the new mode?
>
> Good point. That should not be there. The function can be now reduced
> to a single line again. I originally tried a different approach,
> disabling false timestamps in the new mode, but then I thought it's
> better to not complicate it unnecessarily and keep it consistent.
>
> --
> Miroslav Lichvar