[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Xen-devel] Re: [PATCH 03 of 36] x86: add memory barriers to wrmsr

Arjan van de Ven wrote:
it's more readable for several of these cases to stick a barrier(); in
front and after it to be honest; that makes it more explicit that
these are deliberate compiler barriers rather than "actual" memory

I suppose, though I would be inclined to put the barriers in the wrmsr macro itself to act as documentation. Either way, I don't think there's any legitimate reason to let the compiler reorder things around a wrmsr, and it should be an inherent property of the macro, rather than relying on ad-hoc barriers where it gets used. After all, that's a fairly accurate reflection of how the micro-architecture treats wrmsr...


Xen-devel mailing list



Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.