[PATCH v2 net-next 1/4] net: ethtool: ts: add separate counter for unconfirmed one-step TX timestamps
From: Vladimir Oltean <vladimir.oltean@nxp.com>
Date: 2025-01-16 10:46:46
Subsystem:
documentation, networking drivers, networking [ethtool], networking [general], the rest, yaml netlink (ynl) · Maintainers:
Jonathan Corbet, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, Donald Hunter
For packets with two-step timestamp requests, the hardware timestamp comes back to the driver through a confirmation mechanism of sorts, which allows the driver to confidently bump the successful "pkts" counter. For one-step PTP, the NIC is supposed to autonomously insert its hardware TX timestamp in the packet headers while simultaneously transmitting it. There may be a confirmation that this was done successfully, or there may not. None of the current drivers which implement ethtool_ops :: get_ts_stats() also support HWTSTAMP_TX_ONESTEP_SYNC or HWTSTAMP_TX_ONESTEP_SYNC, so it is a bit unclear which model to follow. But there are NICs, such as DSA, where there is no transmit confirmation at all. Here, it would be wrong / misleading to increment the successful "pkts" counter, because one-step PTP packets can be dropped on TX just like any other packets. So introduce a special counter which signifies "yes, an attempt was made, but we don't know whether it also exited the port or not". I expect that for one-step PTP packets where a confirmation is available, the "pkts" counter would be bumped. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Jakub Kicinski <kuba@kernel.org> --- v1->v2: rebase Documentation/netlink/specs/ethtool.yaml | 3 +++ Documentation/networking/ethtool-netlink.rst | 16 +++++++++++----- include/linux/ethtool.h | 7 +++++++ include/uapi/linux/ethtool_netlink_generated.h | 1 + net/ethtool/tsinfo.c | 2 ++ 5 files changed, 24 insertions(+), 5 deletions(-)
diff --git a/Documentation/netlink/specs/ethtool.yaml b/Documentation/netlink/specs/ethtool.yaml
index 66be04013048..259cb211a338 100644
--- a/Documentation/netlink/specs/ethtool.yaml
+++ b/Documentation/netlink/specs/ethtool.yaml@@ -842,6 +842,9 @@ attribute-sets: - name: tx-err type: uint + - + name: tx-onestep-pkts-unconfirmed + type: uint - name: ts-hwtstamp-provider attr-cnt-name: __ethtool-a-ts-hwtstamp-provider-cnt
diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst
index f70c0249860c..3770a2294509 100644
--- a/Documentation/networking/ethtool-netlink.rst
+++ b/Documentation/networking/ethtool-netlink.rst@@ -1281,11 +1281,17 @@ would be empty (no bit set). Additional hardware timestamping statistics response contents: - ===================================== ====== =================================== - ``ETHTOOL_A_TS_STAT_TX_PKTS`` uint Packets with Tx HW timestamps - ``ETHTOOL_A_TS_STAT_TX_LOST`` uint Tx HW timestamp not arrived count - ``ETHTOOL_A_TS_STAT_TX_ERR`` uint HW error request Tx timestamp count - ===================================== ====== =================================== + ================================================== ====== ===================== + ``ETHTOOL_A_TS_STAT_TX_PKTS`` uint Packets with Tx + HW timestamps + ``ETHTOOL_A_TS_STAT_TX_LOST`` uint Tx HW timestamp + not arrived count + ``ETHTOOL_A_TS_STAT_TX_ERR`` uint HW error request + Tx timestamp count + ``ETHTOOL_A_TS_STAT_TX_ONESTEP_PKTS_UNCONFIRMED`` uint Packets with one-step + HW TX timestamps with + unconfirmed delivery + ================================================== ====== ===================== CABLE_TEST ==========
diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index e4136b0df892..64301ddf2f59 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h@@ -559,6 +559,12 @@ struct ethtool_rmon_stats { /** * struct ethtool_ts_stats - HW timestamping statistics * @pkts: Number of packets successfully timestamped by the hardware. + * @onestep_pkts_unconfirmed: Number of PTP packets with one-step TX + * timestamping that were sent, but for which the + * device offers no confirmation whether they made + * it onto the wire and the timestamp was inserted + * in the originTimestamp or correctionField, or + * not. * @lost: Number of hardware timestamping requests where the timestamping * information from the hardware never arrived for submission with * the skb.
@@ -571,6 +577,7 @@ struct ethtool_rmon_stats { struct ethtool_ts_stats { struct_group(tx_stats, u64 pkts; + u64 onestep_pkts_unconfirmed; u64 lost; u64 err; );
diff --git a/include/uapi/linux/ethtool_netlink_generated.h b/include/uapi/linux/ethtool_netlink_generated.h
index 2e17ff348f89..fe24c3459ac0 100644
--- a/include/uapi/linux/ethtool_netlink_generated.h
+++ b/include/uapi/linux/ethtool_netlink_generated.h@@ -382,6 +382,7 @@ enum { ETHTOOL_A_TS_STAT_TX_PKTS, ETHTOOL_A_TS_STAT_TX_LOST, ETHTOOL_A_TS_STAT_TX_ERR, + ETHTOOL_A_TS_STAT_TX_ONESTEP_PKTS_UNCONFIRMED, __ETHTOOL_A_TS_STAT_CNT, ETHTOOL_A_TS_STAT_MAX = (__ETHTOOL_A_TS_STAT_CNT - 1)
diff --git a/net/ethtool/tsinfo.c b/net/ethtool/tsinfo.c
index 7e495a41aeec..691be6c445b3 100644
--- a/net/ethtool/tsinfo.c
+++ b/net/ethtool/tsinfo.c@@ -186,6 +186,8 @@ static int tsinfo_put_stats(struct sk_buff *skb, if (tsinfo_put_stat(skb, stats->tx_stats.pkts, ETHTOOL_A_TS_STAT_TX_PKTS) || + tsinfo_put_stat(skb, stats->tx_stats.onestep_pkts_unconfirmed, + ETHTOOL_A_TS_STAT_TX_ONESTEP_PKTS_UNCONFIRMED) || tsinfo_put_stat(skb, stats->tx_stats.lost, ETHTOOL_A_TS_STAT_TX_LOST) || tsinfo_put_stat(skb, stats->tx_stats.err,
--
2.43.0