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From: Daniel Phillips <phillips@arcor.de>
To: Rusty Russell <rusty@rustcorp.com.au>,
       Linus Torvalds <torvalds@transmeta.com>
Subject: Re: [patch 6/12] hold atomic kmaps across generic_file_read
Date: Mon, 12 Aug 2002 11:45:32 +0200
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On Monday 12 August 2002 09:45, Rusty Russell wrote:
> On Fri, 9 Aug 2002 18:33:09 -0700 (PDT)
> Linus Torvalds <torvalds@transmeta.com> wrote:
> > 	repeat:
> > 		kmap_atomic(..); // this increments preempt count
> > 		nr = copy_from_user(..);
> 
> Please please please use a different name for "I know I'm not preemptible but
> I can handle it" or a flag or something.
> 
> That leaves us with the possibility of a BUG() in the "normal" copy_to/from_user
> for all those "I'm holding a spinlock while copying to userspace wheeee!" bugs.
> Very common mistake for new kernel authors.

That's the whole point of this: it's not a bug anymore.  (It's a feature.)

But agreed, a different name than preempt count would be nice, because it's
evolving away from its original function.  Is this a 'monitor'?  (I don't
think so.)  Perhaps 'atomic_count' is more accurate.

-- 
Daniel
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