From: Jason Xing <kernelxing@xxxxxxxxxxx>
When the skb is about to send from driver to nic, we can print timestamp
by setting BPF_SOCK_OPS_TS_SW_OPT_CB in bpf program.
Signed-off-by: Jason Xing <kernelxing@xxxxxxxxxxx>
---
include/uapi/linux/bpf.h | 5 +++++
net/core/skbuff.c | 13 ++++++++++---
tools/include/uapi/linux/bpf.h | 5 +++++
3 files changed, 20 insertions(+), 3 deletions(-)
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 3cf3c9c896c7..0d00539f247a 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -7024,6 +7024,11 @@ enum {
* feature is on. It indicates the
* recorded timestamp.
*/
+ BPF_SOCK_OPS_TS_SW_OPT_CB, /* Called when skb is about to send
+ * to the nic when SO_TIMESTAMPING
+ * feature is on. It indicates the
+ * recorded timestamp.
+ */
};
/* List of TCP states. There is a build check in net/ipv4/tcp.c to detect
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 16e7bdc1eacb..832d53de9874 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -5619,7 +5619,8 @@ static void skb_tstamp_tx_output(struct sk_buff *orig_skb,
__skb_complete_tx_timestamp(skb, sk, tstype, opt_stats);
}
-static void bpf_skb_tstamp_tx_output(struct sock *sk, int tstype)
+static void bpf_skb_tstamp_tx_output(struct sock *sk, int tstype,
+ struct skb_shared_hwtstamps *hwtstamps)
{
struct tcp_sock *tp;
u32 tsflags;
@@ -5640,11 +5641,17 @@ static void bpf_skb_tstamp_tx_output(struct sock *sk, int tstype)
case SCM_TSTAMP_SCHED:
cb_flag = BPF_SOCK_OPS_TS_SCHED_OPT_CB;
break;
+ case SCM_TSTAMP_SND:
+ cb_flag = BPF_SOCK_OPS_TS_SW_OPT_CB;
+ break;
default:
return;
}
- tstamp = ktime_to_timespec64(ktime_get_real());
+ if (hwtstamps)
+ tstamp = ktime_to_timespec64(hwtstamps->hwtstamp);
+ else
+ tstamp = ktime_to_timespec64(ktime_get_real());
tcp_call_bpf_2arg(sk, cb_flag, tstamp.tv_sec, tstamp.tv_nsec);
}
}
@@ -5658,7 +5665,7 @@ void __skb_tstamp_tx(struct sk_buff *orig_skb,
return;
if (static_branch_unlikely(&bpf_tstamp_control))
- bpf_skb_tstamp_tx_output(sk, tstype);
+ bpf_skb_tstamp_tx_output(sk, tstype, hwtstamps);
skb_tstamp_tx_output(orig_skb, ack_skb, hwtstamps, sk, tstype);
}
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index d60675e1a5a0..020ec14ffae6 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -7023,6 +7023,11 @@ enum {
* feature is on. It indicates the
* recorded timestamp.
*/
+ BPF_SOCK_OPS_TS_SW_OPT_CB, /* Called when skb is about to send
+ * to the nic when SO_TIMESTAMPING
+ * feature is on. It indicates the
+ * recorded timestamp.
+ */
};
/* List of TCP states. There is a build check in net/ipv4/tcp.c to detect
--
2.37.3
