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Re: [Xen-devel] My turn to rant about types... bitops

On 6 Oct 2005, at 12:28, Jimi Xenidis wrote:

Always the job of the maintainer to ask why :)
Well, since linux bitops use unsigned long, being the largest machine word and therefore the most efficient, we get alignment issues.

The next request is really the jist of what we are after, doing 64bit operations 32bit aligned data kills us performance wise and WRT bitops cannot be used for atomic ops. If htis was just Xen I'd consider adding 32bit bitops but I doubt I'd be able to do that in Linux which does not provide "u32" bitops.

The alignment issue is a fair point. I'll see if changing the type would affect much code.

 -- Keir

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