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From: Rusty Russell <rusty@rustcorp.com.au>
To: Zach Brown <zach.brown@oracle.com>
Subject: Re: [PATCH 5/6] syslets: add generic syslets infrastructure
Date: Thu, 10 Jan 2008 09:04:45 +1100
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On Thursday 10 January 2008 05:16:57 Zach Brown wrote:
> > The latter.  A ring is optimal for processing a huge number of requests,
> > but if you're really going to be firing off syslet threads all over the
> > place you're not going to be optimal anyway.  And being able to point the
> > return value to the stack or into some datastructure is way nicer to code
> > (zero setup == easy to understand and easy to convert).
>
> One of Linus' rhetorical requirements for the syslets work is that we be
> able to wait for the result without spending overhead building up state
> in some completion context.  The userland rings in the current syslet
> patches achieve that and don't seem outrageously complicated.

I'd have to read his original statement, but eventfd doesn't build up state, 
so I think it qualifies.

YA incompatible userspace notification system just doesn't excite me though.

Cheers,
Rusty.