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Re: Modules loading modules?

On Tue Aug 03 2010 at 02:17:43 +1000, matthew green wrote:
> > Now, on to sensible stuff.  I'm quite certain that warning was written
> > to make people avoid writing bad code without understanding locking --
> > if you need to used mutex_owned() to decide if you should lock a normal
> > mutex, your code is broken.  The other less likely possibility is that
> > someone plans to change mutex_owned in the future.
> > 
> > Further data point: the same warning is in rw_held, yet it was used to
> > implement recursive locking in vlockmgr until its very recent demise.
> > 
> > Ignoring man page mantras and focusing on how the code works, I do not
> > see anything wrong with Paul's use of mutex_owned().
> this just does not match my actual experience in the kernel.  i had
> weird pmap-style problems and asserts firing wrongly while i did not
> obey the rules in the manual directly.

Not knowing more details it's difficult to comment.  But since you are
talking about the pmap, maybe your experiences are with spin mutexes
instead of adaptive ones?

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