diff options
| author | Jason Xing <kernelxing@tencent.com> | 2024-09-09 09:56:11 +0800 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2024-09-10 16:55:23 -0700 |
| commit | be8e9eb3750639aa5cffb3f764ca080caed41bd0 (patch) | |
| tree | ab6a286d9ab8afbdf8b77668935b8b7864bbb8b5 /net/socket.c | |
| parent | e503f82e304b039332226008addac9d13ac68cb9 (diff) | |
net-timestamp: introduce SOF_TIMESTAMPING_OPT_RX_FILTER flag
introduce a new flag SOF_TIMESTAMPING_OPT_RX_FILTER in the receive
path. User can set it with SOF_TIMESTAMPING_SOFTWARE to filter
out rx software timestamp report, especially after a process turns on
netstamp_needed_key which can time stamp every incoming skb.
Previously, we found out if an application starts first which turns on
netstamp_needed_key, then another one only passing SOF_TIMESTAMPING_SOFTWARE
could also get rx timestamp. Now we handle this case by introducing this
new flag without breaking users.
Quoting Willem to explain why we need the flag:
"why a process would want to request software timestamp reporting, but
not receive software timestamp generation. The only use I see is when
the application does request
SOF_TIMESTAMPING_SOFTWARE | SOF_TIMESTAMPING_TX_SOFTWARE."
Similarly, this new flag could also be used for hardware case where we
can set it with SOF_TIMESTAMPING_RAW_HARDWARE, then we won't receive
hardware receive timestamp.
Another thing about errqueue in this patch I have a few words to say:
In this case, we need to handle the egress path carefully, or else
reporting the tx timestamp will fail. Egress path and ingress path will
finally call sock_recv_timestamp(). We have to distinguish them.
Errqueue is a good indicator to reflect the flow direction.
Suggested-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20240909015612.3856-2-kerneljasonxing@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/socket.c')
| -rw-r--r-- | net/socket.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/net/socket.c b/net/socket.c index 0a2bd22ec105..8d8b84fa404a 100644 --- a/net/socket.c +++ b/net/socket.c @@ -946,11 +946,17 @@ void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk, memset(&tss, 0, sizeof(tss)); tsflags = READ_ONCE(sk->sk_tsflags); - if ((tsflags & SOF_TIMESTAMPING_SOFTWARE) && + if ((tsflags & SOF_TIMESTAMPING_SOFTWARE && + (tsflags & SOF_TIMESTAMPING_RX_SOFTWARE || + skb_is_err_queue(skb) || + !(tsflags & SOF_TIMESTAMPING_OPT_RX_FILTER))) && ktime_to_timespec64_cond(skb->tstamp, tss.ts + 0)) empty = 0; if (shhwtstamps && - (tsflags & SOF_TIMESTAMPING_RAW_HARDWARE) && + (tsflags & SOF_TIMESTAMPING_RAW_HARDWARE && + (tsflags & SOF_TIMESTAMPING_RX_HARDWARE || + skb_is_err_queue(skb) || + !(tsflags & SOF_TIMESTAMPING_OPT_RX_FILTER))) && !skb_is_swtx_tstamp(skb, false_tstamp)) { if_index = 0; if (skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP_NETDEV) |