Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 9 Jul 2002 14:18:42 -0400 (EDT)
From:      Robert Watson <rwatson@FreeBSD.org>
To:        John Baldwin <jhb@FreeBSD.org>
Cc:        Julian Elischer <julian@elischer.org>, FreeBSD current users <current@FreeBSD.org>
Subject:   RE: KSE M-III status & junior hacker project.
Message-ID:  <Pine.NEB.3.96L.1020709141140.58636B-100000@fledge.watson.org>
In-Reply-To: <XFMail.20020709084029.jhb@FreeBSD.org>

next in thread | previous in thread | raw e-mail | index | archive | help

On Tue, 9 Jul 2002, John Baldwin wrote:

> > If anyone knows of something that was broken by the KSE commit,
> > (i.e. it worked just before and not after) and is STILL
> > broken please let me know because I think I can pretty much declare that
> > chapter finished, and I'd like to get on with "extending" KSE
> > functionality. This will be the start of Milestone IV, which would be
> > add support for threads to run on multiple processors.
> > Coincident with that some work should also proceed on gradually
> > identifying and cleaning up places in the kernel where multithreading
> > is just not ready.. e.g. which thread status do you get when you type ^T?
> 
> I would like it if you would make KSE-3 work on other architectures now
> rather than adding more functionality that only works on i386.  This
> would serve to validate the design decisions made thus far before a
> whole lot of code depends on those design decisions making it easier to
> make changes if need be. 

I have to admit I got a bit nervous about the KSE work on learning that
the existing fork-like approach was not compatible with several of our new
(or existing) target architectures; my impression was Julian and Doug had
hashed out a good solution to the problem at the dev summit last month,
however.  I agree that getting at least one non-i386 platform working at
this point is really an important priority, since we really don't want to
bump into any more such problems.  Also, since we're now getting to the
point where userland work is feasible, I think it's important that we
start to congeal a bit more on the multi-platform aware interface to avoid
building in assumptions that will be broken later resulting in a lot more
work.

Julian--following your conversation/design session with Doug, how long do
you think it would take to get i386 moved over to the revised design, and
then assuming you and someone infinitely familiar with the target platform
sat down together, how long would it take to bootstrap at least one more
platform to work with KSE?  I tend to agree with John that this is an
important thing to have happen before we get too much more featureful.  To
make an additional platform happen (say, Alpha or Sparc64), what would it
take in terms of expertise you don't have -- just someone familiar with
the architecture's context management and kernel trap code?  I.e., a day
or two of Doug's, Jake's, or Peter's time?

Robert N M Watson             FreeBSD Core Team, TrustedBSD Projects
robert@fledge.watson.org      Network Associates Laboratories




To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-current" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.NEB.3.96L.1020709141140.58636B-100000>