[DCCP]: Simplify interface of dccp_sample_rtt

The third parameter of dccp_sample_rtt now becomes useless and is removed.

Also combined the subtraction of the timestamp echo and the elapsed time.
This is safe, since (a) presence of timestamp echo is tested first and (b)
elapsed time is either present and non-zero or it is not set and equals 0
due to the memset in dccp_parse_options.

To avoid measuring option-processing time, the timestamp for measuring the
initial Request/Response RTT sample is taken directly when the function is
called (the Linux implementation always adds a timestamp on the Request,
so there is no loss in doing this).

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 2 deletions

diff --git a/net/dccp/dccp.h b/net/dccp/dccp.h
index a75c740ae6c0..bd4645b3a36c 100644
--- a/net/dccp/dccp.h
+++ b/net/dccp/dccp.h
@@ -297,8 +297,7 @@ extern int	   dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr,
 extern int         dccp_send_reset(struct sock *sk, enum dccp_reset_codes code);
 extern void        dccp_send_close(struct sock *sk, const int active);
 extern int         dccp_invalid_packet(struct sk_buff *skb);
-extern u32         dccp_sample_rtt(struct sock *sk, ktime_t t_recv,
-                                   ktime_t *t_history);
+extern u32         dccp_sample_rtt(struct sock *sk, long delta);
 
 static inline int dccp_bad_service_code(const struct sock *sk,
                                         const __be32 service)