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From: Rusty Russell <rusty@rustcorp.com.au>
To: Pavel Machek <pavel@ucw.cz>
Cc: linux-kernel@vger.kernel.org
Subject: Re: Module Refcount & Stuff mini-FAQ 
In-reply-to: Your message of "Sat, 23 Nov 2002 23:23:34 BST."
             <20021123222334.GB5170@elf.ucw.cz> 
Date: Mon, 25 Nov 2002 11:26:25 +1100
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In message <20021123222334.GB5170@elf.ucw.cz> you write:
> Hi!
> 
> > Q: How does the module remove code work?
> > A: It stops the machine by scheduling threads for every other CPU,
> >    then they all disable interrupts.  At this stage we know that noone
> >    is in try_module_get(), so we can reliably read the counter.  If
> >    zero, or the rmmod user specified --wait, we set the live flag to
> >    false.  After this, the reference count should not increase, and
> >    each module_put() will wake us up, so we can check the counter
> >    again.
> 
> Where is this implemented? I guess I need this for swsusp...

I'm not so sure, but it's worth a look.  Look for stop_refcounts() in
module.c.  BTW, I call this a "bogolock".

Rusty.
--
  Anyone who quotes me in their sig is an idiot. -- Rusty Russell.
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