Re: [9fans] 9vx, kproc and *double sleep*

[erik quanstrom <quanstro@quanstro.net>]

On Fri Jun 11 10:54:40 EDT 2010, xigh@bouyapop.org wrote:
> I don't think either splhi fixes the problem ... it only hides it for
> the 99.999999999% cases.

on a casual reading, i agree.  unfortunately,
the current simplified promela model disagrees,
and coraid has run millions of cpu-hrs on quad
processor machines running near 100% load
with up to 1500 procs, and never seen this.

unless you have a good reason why we've never
seen such a deadlock, i'm inclined to believe
we're missing something.  we need better reasons
for sticking locks in than guesswork.
multiple locks can easily lead to deadlock.

have you tried your solution with a single Mach?

> No ... I don't think so. I think the problem comes from the fact the
> process is no longer exclusively tied to the current Mach when going
> (back) to schedinit() ... hence the change I did.

have you tried?  worst case is you'll have more
information on the problem.

- erik