dccp: make implementation of Syn-RTT symmetric
commit59b80802a8a18b64d38b51aa168253684b2649d5
authorGerrit Renker <gerrit@erg.abdn.ac.uk>
Tue, 22 Jun 2010 01:14:35 +0000 (22 01:14 +0000)
committerDavid S. Miller <davem@davemloft.net>
Sat, 26 Jun 2010 04:33:15 +0000 (25 21:33 -0700)
treeb6be92f705d00796733e03e43041605b74d0ce5f
parenta7d13fbf85375698879d16f118af77fbfcc2de44
dccp: make implementation of Syn-RTT symmetric

This patch is thanks to Andre Noll who reported the issue and helped testing.

The Syn-RTT sampled during the initial handshake currently only works for
the client sending the DCCP-Request. TFRC penalizes the absence of an RTT
sample with a very slow initial speed (1 packet per second), which delays
slow-start significantly, resulting in sluggish performance.

This patch mirrors the "Syn RTT" principle by adding a timestamp also onto
the DCCP-Response, producing an RTT sample  when the (Data)Ack completing
the handshake arrives.

Also changed the documentation to 'TFRC' since Syn RTTs are also used by CCID-4.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/dccp/input.c
net/dccp/options.c