[PATCH] Document Linux's memory barriers [try #2]

David Howells dhowells at redhat.com
Thu Mar 9 06:08:42 EST 2006

Alan Cox <alan at redhat.com> wrote:

> 	spin_lock(&foo->lock);
> 	writel(0, &foo->regnum);

I presume there only needs to be an mmiowb() here if you've got the
appropriate CPU's I/O memory window set up to be weakly ordered.

> 	writel(1, &foo->data);
> 	mmiowb();
> 	spin_unlock(&foo->lock);


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