[NET]: Adding SO_TIMESTAMPNS / SCM_TIMESTAMPNS support
Now that network timestamps use ktime_t infrastructure, we can add a new
SOL_SOCKET sockopt SO_TIMESTAMPNS.
This command is similar to SO_TIMESTAMP, but permits transmission of
a 'timespec struct' instead of a 'timeval struct' control message.
(nanosecond resolution instead of microsecond)
Control message is labelled SCM_TIMESTAMPNS instead of SCM_TIMESTAMP
A socket cannot mix SO_TIMESTAMP and SO_TIMESTAMPNS : the two modes are
mutually exclusive.
sock_recv_timestamp() became too big to be fully inlined so I added a
__sock_recv_timestamp() helper function.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
CC: linux-arch@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/socket.c b/net/socket.c
index cf18c5e..a7bd0df 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -585,6 +585,35 @@
return result;
}
+/*
+ * called from sock_recv_timestamp() if sock_flag(sk, SOCK_RCVTSTAMP)
+ */
+void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
+ struct sk_buff *skb)
+{
+ ktime_t kt = skb->tstamp;
+
+ if (!sock_flag(sk, SOCK_RCVTSTAMPNS)) {
+ struct timeval tv;
+ /* Race occurred between timestamp enabling and packet
+ receiving. Fill in the current time for now. */
+ if (kt.tv64 == 0)
+ kt = ktime_get_real();
+ skb->tstamp = kt;
+ tv = ktime_to_timeval(kt);
+ put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMP, sizeof(tv), &tv);
+ } else {
+ struct timespec ts;
+ /* Race occurred between timestamp enabling and packet
+ receiving. Fill in the current time for now. */
+ if (kt.tv64 == 0)
+ kt = ktime_get_real();
+ skb->tstamp = kt;
+ ts = ktime_to_timespec(kt);
+ put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMPNS, sizeof(ts), &ts);
+ }
+}
+
static inline int __sock_recvmsg(struct kiocb *iocb, struct socket *sock,
struct msghdr *msg, size_t size, int flags)
{