On Thu, Feb 13, 2025 at 8:07 AM Jason Xing <kerneljasonxing@xxxxxxxxx> wrote: > > On Wed, Feb 12, 2025 at 11:26 PM Willem de Bruijn > <willemdebruijn.kernel@xxxxxxxxx> wrote: > > > > Jason Xing wrote: > > > Support the ACK case for bpf timestamping. > > > > > > Add a new sock_ops callback, BPF_SOCK_OPS_TS_ACK_OPT_CB. This > > > callback will occur at the same timestamping point as the user > > > space's SCM_TSTAMP_ACK. The BPF program can use it to get the > > > same SCM_TSTAMP_ACK timestamp without modifying the user-space > > > application. > > > > > > This patch extends txstamp_ack to two bits: 1 stands for > > > SO_TIMESTAMPING mode, 2 bpf extension. > > > > > > Signed-off-by: Jason Xing <kerneljasonxing@xxxxxxxxx> > > > --- > > > include/net/tcp.h | 6 ++++-- > > > include/uapi/linux/bpf.h | 5 +++++ > > > net/core/skbuff.c | 5 ++++- > > > net/dsa/user.c | 2 +- > > > net/ipv4/tcp.c | 2 +- > > > net/socket.c | 2 +- > > > tools/include/uapi/linux/bpf.h | 5 +++++ > > > 7 files changed, 21 insertions(+), 6 deletions(-) > > > > > diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c > > > index 0d704bda6c41..aa080f7ccea4 100644 > > > --- a/net/ipv4/tcp.c > > > +++ b/net/ipv4/tcp.c > > > @@ -488,7 +488,7 @@ static void tcp_tx_timestamp(struct sock *sk, struct sockcm_cookie *sockc) > > > > > > sock_tx_timestamp(sk, sockc, &shinfo->tx_flags); > > > if (tsflags & SOF_TIMESTAMPING_TX_ACK) > > > - tcb->txstamp_ack = 1; > > > + tcb->txstamp_ack = TSTAMP_ACK_SK; > > > > Similar to the BPF code, should this by |= TSTAMP_ACK_SK? > > > > Does not matter in practice if the BPF setter can never precede this. > > I gave the same thought on this too. We've already fixed the position > and order (of using socket timestamping and bpf timestamping). > > I have no strong preference. If you insist, I can surely adjust it. I updated it in the next version locally :) > > Thanks, > Jason
