Re: Question about memory barriers

From: Randy.Dunlap
Date: Thu Feb 02 2006 - 16:50:52 EST


On Thu, 2 Feb 2006, Alan Stern wrote:

> On Thu, 2 Feb 2006, Roland Dreier wrote:
>
> > Most of this is correct, except that mb() is stronger than just rmb()
> > and wmb() put together. All memory operations before the mb() will
> > complete before any operations after the mb(). A better way to
> > understand this is to look at the sparc64 definition:
> >
> > #define mb() \
> > membar_safe("#LoadLoad | #LoadStore | #StoreStore | #StoreLoad")
>
> Thanks for the explanation. Is there any appropriate place, say in
> Documentation/, where these things could be spelled out more completely?

Info could be added to Documentation/DocBook/kernel-locking.tmpl
which already has some barrier info.

--
~Randy
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