Re: atomics: document that linux expects certain atomic behaviour from unsigned long

[Pavel Machek <pavel@suse.cz>]

On Sat 2009-01-03 20:30:44, Alan Cox wrote:
> > If it is okay and linux relies on it, it should be documented.
> > 
> > If it is not okay, I guess we should document it, too -- it seems to
> > be common mistake. 
> 
> A lot of old code did it knowing it was under the BKL, outside of the BKL
> its a very bad idea. There were lots of them in the tty layer and I don't
> doubt there are some left I missed too 8(

I have seen this in new code (some LED driver last time), definitely
no BKL.

Is there concrete architecture where it breaks? I'd expect i386/x86-64
to be safe, and pretty much everyone to be safe as long as that long
is aligned.... or that was the result of arch-maintainers
discussion...

I'd really like to document if it is right or not, so that I can point
people to documentation...
								Pavel
-- 
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