Re: [PATCH] Document Linux's memory barriers [try #4]

[Sergei Organov]

David Howells <dhowells@xxxxxxxxxx> writes:

> Sergei Organov <osv@xxxxxxxxx> wrote:
>
>> > +In addition, accesses to "volatile" memory locations and volatile asm
>> > +statements act as implicit compiler barriers.
>> 
>> This last statement seems to contradict with what GCC manual says about
>> volatile asm statements:
>
> Perhaps I should say "compiler memory barrier", since it doesn't prevent
> instructions from being moved, but rather merely affects the ordering of
> memory accesses and volatile instructions.

Well, I'd just remove the two lines in question as neither volatile
access nor volatile asm are barriers, -- that's why the barrier() is
needed in the first place.

-- Sergei.
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