Before committing the initial tcp_hostcache I changed them from memcpy()
to conform with FreeBSD style without realizing the difference in argument
definition.
This fixes hostcache operation for IPv6 (in general and explicitly IPv6
path mtu discovery) and T/TCP (RFC1644).
Submitted by: Taku YAMAMOTO <taku@cent.saitama-u.ac.jp>
Approved by: re (rwatson)
When the hostcache bucket limit is reached the last bucket wasn't
removed from the bucket row but inserted a few lines later at the
bucket row head again. This leads to infinite loop when the same
bucket row is accessed the next time for a lookup/insert or purge
action.
Tested by: imp, Matt Smith
Approved by: re (rwatson)
the routing table. Move all usage and references in the tcp stack
from the routing table metrics to the tcp hostcache.
It caches measured parameters of past tcp sessions to provide better
initial start values for following connections from or to the same
source or destination. Depending on the network parameters to/from
the remote host this can lead to significant speedups for new tcp
connections after the first one because they inherit and shortcut
the learning curve.
tcp_hostcache is designed for multiple concurrent access in SMP
environments with high contention and is hash indexed by remote
ip address.
It removes significant locking requirements from the tcp stack with
regard to the routing table.
Reviewed by: sam (mentor), bms
Reviewed by: -net, -current, core@kame.net (IPv6 parts)
Approved by: re (scottl)
