From: Gerrit Renker Date: Fri, 27 Feb 2009 22:38:28 +0000 (+0000) Subject: dccp: Minimise header option overhead in setting the MPS X-Git-Tag: v2.6.30-rc1~662^2~432 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=361a5c1dd0bd7bb2b90e7fe9127b366d3566522e;p=pandora-kernel.git dccp: Minimise header option overhead in setting the MPS This patch resolves a long-standing FIXME to dynamically update the Maximum Packet Size depending on actual options usage. It uses the flags set by the feature-negotiation infrastructure to compute the required header option size. Most options are fixed-size, a notable exception are Ack Vectors (required currently only by CCID-2). These can have any length between 3 and 1020 bytes. As a result of testing, 16 bytes (2 bytes for type/length plus 14 Ack Vector cells) have been found to be sufficient for loss-free situations. There are currently no CCID-specific header options which may appear on data packets, thus it is not necessary to define a corresponding CCID field as suggested in the old comment. Further changes: ---------------- Adjusted the type of 'cur_mps' to match the unsigned return type of the function. Signed-off-by: Gerrit Renker Acked-by: Ian McDonald Signed-off-by: David S. Miller --- Reading git-diff-tree failed