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From: Doug Rabson <dfr@nlsystems.com>
To: Peter A Jonsson <pj@ludd.ltu.se>
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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.