Re: WITNESS bug

From: John Baldwin <jhb_at_freebsd.org>
Date: Tue, 19 Oct 2004 16:50:28 -0400
On Tuesday 19 October 2004 12:01 pm, Kris Kennaway wrote:
> On Tue, Oct 19, 2004 at 09:13:26AM -0400, Robert Huff wrote:
> > Brian Fundakowski Feldman writes:
> > >  You should never not run with WITNESS_SKIPSPIN if you use
> > >  modules.  Any spin mutexes not listed statically in the witness
> > >  code will cause your machine to immediately panic.
> >
> > 	If this is true (and I'm not disputing it), shouldn't it be
> > noted in GENERIC and/or NOTES?  For that matter, what's the penalty
> > for not automatically including it as part of WITNESS?
>
> Sometimes you don't want to use it, e.g. if you actually want to trace
> spinlock operations with witness.

True spin mutexes should be rarely used anyways, so I don't think modules 
needing spin mutexes is all that big of an issue.  Almost all mutexes should 
just be regular mutexes.

-- 

John Baldwin <jhb_at_FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve!"  -  http://www.FreeBSD.org/
Received on Tue Oct 19 2004 - 19:13:19 UTC

This archive was generated by hypermail 2.4.0 : Wed May 19 2021 - 11:38:18 UTC