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/net/sock.h | 10 ++++++++++ include/uapi/asm-generic/socket.h | 3 +++ include/uapi/linux/net_tstamp.h | 15 +++++++++++++++ 3 files changed, 28 insertions(+) (limited to 'include') diff --git a/include/net/sock.h b/include/net/sock.h index 2ed99bfa4595..68347b9821c6 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -319,6 +319,9 @@ struct sock_common { * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0 * @sk_reuseport_cb: reuseport group container * @sk_rcu: used during RCU grace period + * @sk_clockid: clockid used by time-based scheduling (SO_TXTIME) + * @sk_txtime_deadline_mode: set deadline mode for SO_TXTIME + * @sk_txtime_unused: unused txtime flags */ struct sock { /* @@ -475,6 +478,11 @@ struct sock { u8 sk_shutdown; u32 sk_tskey; atomic_t sk_zckey; + + u8 sk_clockid; + u8 sk_txtime_deadline_mode : 1, + sk_txtime_unused : 7; + struct socket *sk_socket; void *sk_user_data; #ifdef CONFIG_SECURITY @@ -790,6 +798,7 @@ enum sock_flags { SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */ SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */ SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */ + SOCK_TXTIME, }; #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)) @@ -1585,6 +1594,7 @@ void sock_kzfree_s(struct sock *sk, void *mem, int size); void sk_send_sigurg(struct sock *sk); struct sockcm_cookie { + u64 transmit_time; u32 mark; u16 tsflags; }; diff --git a/include/uapi/asm-generic/socket.h b/include/uapi/asm-generic/socket.h index 0ae758c90e54..a12692e5f7a8 100644 --- a/include/uapi/asm-generic/socket.h +++ b/include/uapi/asm-generic/socket.h @@ -107,4 +107,7 @@ #define SO_ZEROCOPY 60 +#define SO_TXTIME 61 +#define SCM_TXTIME SO_TXTIME + #endif /* __ASM_GENERIC_SOCKET_H */ 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