Re: Memory barriers and spin_unlock safety

From: Hollis Blanchard
Date: Fri Mar 03 2006 - 16:16:03 EST


On Friday 03 March 2006 15:06, Benjamin Herrenschmidt wrote:
> The main problem I've had in the past with the ppc barriers is more a
> subtle thing in the spec that unfortunately was taken to the word by
> implementors, and is that the simple write barrier (eieio) will only
> order within the same storage space, that is will not order between
> cacheable and non-cacheable storage.

I've heard Sparc has the same issue... in which case it may not be a "chip
designer was too literal" thing, but rather it really simplifies chip
implementation to do it that way.

--
Hollis Blanchard
IBM Linux Technology Center
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/