From 80b14dee2bea128928537d61c333f24cb8cbb62f Mon Sep 17 00:00:00 2001 From: Richard Cochran Date: Tue, 3 Jul 2018 15:42:48 -0700 Subject: net: Add a new socket option for a future transmit time. This patch introduces SO_TXTIME. User space enables this option in order to pass a desired future transmit time in a CMSG when calling sendmsg(2). The argument to this socket option is a 8-bytes long struct provided by the uapi header net_tstamp.h defined as: struct sock_txtime { clockid_t clockid; u32 flags; }; Note that new fields were added to struct sock by filling a 2-bytes hole found in the struct. For that reason, neither the struct size or number of cachelines were altered. Signed-off-by: Richard Cochran Signed-off-by: Jesus Sanchez-Palencia Signed-off-by: David S. Miller --- include/uapi/linux/net_tstamp.h | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/net_tstamp.h b/include/uapi/linux/net_tstamp.h index 4fe104b2411f..c9a77c353b98 100644 --- a/include/uapi/linux/net_tstamp.h +++ b/include/uapi/linux/net_tstamp.h @@ -141,4 +141,19 @@ struct scm_ts_pktinfo { __u32 reserved[2]; }; +/* + * SO_TXTIME gets a struct sock_txtime with flags being an integer bit + * field comprised of these values. + */ +enum txtime_flags { + SOF_TXTIME_DEADLINE_MODE = (1 << 0), + + SOF_TXTIME_FLAGS_MASK = (SOF_TXTIME_DEADLINE_MODE) +}; + +struct sock_txtime { + clockid_t clockid; /* reference clockid */ + u32 flags; /* flags defined by enum txtime_flags */ +}; + #endif /* _NET_TIMESTAMPING_H */ -- cgit v1.2.3