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 | 19 ++++++++++++++++---
tools/include/uapi/linux/bpf.h | 5 +++++
3 files changed, 26 insertions(+), 3 deletions(-)
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 324e9e40969c..b0032e173e65 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -7018,6 +7018,11 @@ 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 e6a5c883bdc6..e29ab3e45213 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -5640,8 +5640,10 @@ static void timestamp_call_bpf(struct sock *sk, int op, u32 nargs, u32 *args)
BPF_CGROUP_RUN_PROG_SOCK_OPS_SK(&sock_ops, sk);
}
-static void skb_tstamp_tx_output_bpf(struct sock *sk, int tstype)
+static void skb_tstamp_tx_output_bpf(struct sock *sk, int tstype,
+ struct skb_shared_hwtstamps *hwtstamps)
{
+ u32 args[2] = {0, 0};
u32 tsflags, cb_flag;
tsflags = READ_ONCE(sk->sk_tsflags_bpf);
@@ -5652,11 +5654,22 @@ static void skb_tstamp_tx_output_bpf(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;
}
- timestamp_call_bpf(sk, cb_flag, 0, NULL);
+ if (hwtstamps) {
+ struct timespec64 ts;
+
+ ts = ktime_to_timespec64(hwtstamps->hwtstamp);
+ args[0] = ts.tv_sec;
+ args[1] = ts.tv_nsec;
+ }
+
+ timestamp_call_bpf(sk, cb_flag, 2, args);
}
void __skb_tstamp_tx(struct sk_buff *orig_skb,
@@ -5667,7 +5680,7 @@ void __skb_tstamp_tx(struct sk_buff *orig_skb,
if (!sk)
return;
- skb_tstamp_tx_output_bpf(sk, tstype);
+ skb_tstamp_tx_output_bpf(sk, tstype, hwtstamps);
skb_tstamp_tx_output(orig_skb, ack_skb, hwtstamps, sk, tstype);
}
EXPORT_SYMBOL_GPL(__skb_tstamp_tx);
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 324e9e40969c..b0032e173e65 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -7018,6 +7018,11 @@ 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
