Read Copy Update

[Doug White]

On Thu, 19 Feb 2004, Doug Rabson wrote:

> On Thu, 2004-02-19 at 16:26, Peter A Jonsson wrote:
> > > I imagine that a FreeBSD implementation of RCU wouldn't actually be too
> > > hard and it might be well worth it as an alternative way of managing
> > > concurrency, e.g. for the routing cache and the name cache (and probably
> > > lots of other things).
> >
> > Alan Cox pointed out[1] that there was a patent problem (US Patent
> > #05442758 [2]) with RCU which prevented inclusion in the Linux
> > kernel. This was solved[3] by granting the right to use it in GPL
> > software according to my understanding. Isn't this a problem for
> > FreeBSD?
>
> That would be a problem unless the patent owner (Sequent, i.e. IBM)
> could be encouraged to grant a similar license for BSD software.

Note that SCO is trying to claim that RCU is derviative of SysV, so it
might be a good idea to steer clear of this until that issue is
resolved... which might be a while. :)

-- 
Doug White                    |  FreeBSD: The Power to Serve
dwhite at gumbysoft.com          |  www.FreeBSD.org