Re: [PATCH] I/O space write barrier

[Benjamin Herrenschmidt]

> I agree, it's hard to get right, especially when you've got a large base of 
> drivers with hard to find assumptions about ordering.
> 
> What about mmiowb()?  Should it be eieio?  I don't want to post another patch 
> if I don't have to...

I don't understand the whole story...

If normal accesses aren't relaxed (and I think they shouldn't be), then
there is no point in a barrier here.... If you need an explicit barrier
for explicitely relaxed accesses, then yes.

That doesn't solve my need of MMIO vs. memory unless you are trying to
cover that as well, in which case it should be a sync.

Ben.


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