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From: Robert Watson <rwatson@freebsd.org>
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To: Julian Elischer <julian@elischer.org>
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Subject: Re: Network Stack Locking
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On Tue, 25 May 2004, Julian Elischer wrote:

> This is how netgraph works.  (particularly in 5.x) 

It's also worth pointing out, for those looking at various approaches,
that NetBSD is currently discussing continuation primitives on the
tech-kern mailing list (I seem to have gotten added to the CC line lately,
which I don't object to :-).

You can also argue that things like bio's, PCB's, et al, are
implementations of the continuation philosophy, just lacking a abstracted
primitive.  They maintain state to be picked up by a context but
discarding the stack.  Callouts and callbacks are used to perform
scheduling, however, rather than the scheduler explicitly. 

Robert N M Watson             FreeBSD Core Team, TrustedBSD Projects
robert@fledge.watson.org      Senior Research Scientist, McAfee Research