Re: [PATCH 0/24] make atomic_read() behave consistently across all architectures

[Herbert Xu]

On Thu, Aug 16, 2007 at 07:45:44AM +0530, Satyam Sharma wrote:
>
> Completely agreed, again. To summarize again (had done so about ~100 mails
> earlier in this thread too :-) ...
> 
> atomic_{read,set}_volatile() -- guarantees volatility also along with
> atomicity (the two _are_ different concepts after all, irrespective of
> whether callsites normally want one with the other or not)
> 
> atomic_{read,set}_nonvolatile() -- only guarantees atomicity, compiler
> free to elid / coalesce / optimize such accesses, can keep the object
> in question cached in a local register, leads to smaller text, etc.
> 
> As to which one should be the default atomic_read() is a question of
> whether majority of callsites (more weightage to important / hot
> codepaths, lesser to obscure callsites) want a particular behaviour.
> 
> Do we have a consensus here? (hoping against hope, probably :-)

I can certainly agree with this.

But I have to say that I still don't know of a single place
where one would actually use the volatile variant.

Cheers,
-- 
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