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SubjectRe: set_current_state
Date
> 
> On Sun, 5 Sep 1999, Jamie Lokier wrote:
>
> >AFAIK the ordering of volatile operations is only defined with respect
> >to each other.
>
> I thought the rule was different. If that is true we should add a
> barrier() after setting current->state in the UP code. Are you 100% sure
> that the compiler can move not-volatile data read/write across the write
> of a volatile var?
>
> I can't find this information into the gcc info docs.
It's defined in the C-standard.

I checked it, and I think the barrier() calls are not required:
5.1.3: "At sequence points, volatile objects are stable [...]"

Annex C: sequence points are
* function calls
* the end of a full expression.
* [...]
--
Manfred

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