From be8e9eb3750639aa5cffb3f764ca080caed41bd0 Mon Sep 17 00:00:00 2001 From: Jason Xing Date: Mon, 9 Sep 2024 09:56:11 +0800 Subject: 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 Signed-off-by: Jason Xing Reviewed-by: Willem de Bruijn Link: https://patch.msgid.link/20240909015612.3856-2-kerneljasonxing@gmail.com Signed-off-by: Jakub Kicinski --- include/uapi/linux/net_tstamp.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include/uapi') diff --git a/include/uapi/linux/net_tstamp.h b/include/uapi/linux/net_tstamp.h index a2c66b3d7f0f..858339d1c1c4 100644 --- a/include/uapi/linux/net_tstamp.h +++ b/include/uapi/linux/net_tstamp.h @@ -32,8 +32,9 @@ enum { SOF_TIMESTAMPING_OPT_TX_SWHW = (1<<14), SOF_TIMESTAMPING_BIND_PHC = (1 << 15), SOF_TIMESTAMPING_OPT_ID_TCP = (1 << 16), + SOF_TIMESTAMPING_OPT_RX_FILTER = (1 << 17), - SOF_TIMESTAMPING_LAST = SOF_TIMESTAMPING_OPT_ID_TCP, + SOF_TIMESTAMPING_LAST = SOF_TIMESTAMPING_OPT_RX_FILTER, SOF_TIMESTAMPING_MASK = (SOF_TIMESTAMPING_LAST - 1) | SOF_TIMESTAMPING_LAST }; -- cgit v1.2.3