Re: [PATCH net-next v2 5/6] bpf: enable bpf timestamping rx in TCP layer
From: Kuniyuki Iwashima <kuniyu@google.com>
Date: 2026-05-23 03:45:30
Also in:
bpf
On Thu, May 21, 2026 at 6:53 AM Jason Xing [off-list ref] wrote:
quoted hunk ↗ jump to hunk
From: Jason Xing <kernelxing@tencent.com> Add two if statements to accurately isolate bpf timestamping and so timestamping. They can work respectively. As to so_timestamping, only add a loose condition via report flags to avoid duplicate strict checks that is done in tcp_recv_timestamp() and performance impact. If the loose condition is hit, tcp_recv_timestamp() is able to handle the exact case and doesn't hamper the existing timestamping feature. Make it work in TCP protocol. Signed-off-by: Jason Xing <kernelxing@tencent.com> --- net/ipv4/tcp.c | 10 ++++++++++ 1 file changed, 10 insertions(+)diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 21ece4c71612..7ad3561dc8cd 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c@@ -2353,6 +2353,16 @@ void tcp_recv_timestamp(struct msghdr *msg, const struct sock *sk,
Simply drop const from here rather than casting to non-const for bpf_skops_rx_timestamping(). sk in all callers of tcp_recv_timestamp() is not const.
int new_tstamp = sock_flag(sk, SOCK_TSTAMP_NEW);
u32 tsflags = READ_ONCE(sk->sk_tsflags);
+ if (cgroup_bpf_enabled(CGROUP_SOCK_OPS) &&
+ SK_BPF_CB_FLAG_TEST(sk, SK_BPF_CB_RX_TIMESTAMPING))
+ bpf_skops_rx_timestamping((struct sock *)sk, tss,
+ BPF_SOCK_OPS_TSTAMP_RCV_CB);
+
+ if (!sock_flag(sk, SOCK_RCVTSTAMP) &&
+ !(tsflags & SOF_TIMESTAMPING_SOFTWARE) &&
+ !(tsflags & SOF_TIMESTAMPING_RAW_HARDWARE))
+ return;
+
if (tss->ts[0]) {
if (sock_flag(sk, SOCK_RCVTSTAMP)) {
struct timespec64 tv = ktime_to_timespec64(tss->ts[0]);
--
2.43.7