Subject: Re: SMP re-entrancy in kernel drivers/"bottom half?"
To: Jonathan Stone <jonathan@dsg.stanford.edu>
From: Bill Studenmund <wrstuden@netbsd.org>
List: tech-kern
Date: 03/01/2005 19:36:28
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On Wed, Feb 23, 2005 at 07:22:58AM +0000, David Laight wrote:
> > David (no sarcasm here): huh? I must be misunderstanding you, because
> > that seems bizarre.  How on earth do you get two CPUs running in the
> > upper-half context of the same process "easily" and "with greater
> > benefit", starting from where NetBSD is now?
>=20
> Because I am thinking of server data flows - where there are multiple
> applications generating ther data.  The amount of processing required
> for a TCP transmit should be fairly limited.  You only need to write-lock
> the per-connection data to update the sequence numbers, and the MAC code
> to grab a slot in the ring.  Usually a single PCI access is enough to
> kick the hardware.

I have to agree with Jonathan here that that's not all we want. I'm VERY=20
interested in being able to deal with one application generating a lot of=
=20
data.

Take care,

Bill

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