Re: [PATCH 04/11] x86/fpu: eager switch PKRU state

From: Dave Hansen
Date: Fri Oct 12 2018 - 15:44:42 EST


On 10/12/2018 11:09 AM, Andy Lutomirski wrote:
> But maybe WRPKRU is more expensive than RDPKRU and a branch?

Yeah, it is more expensive. It has a higher cycle cost and it's also
practically a (light) speculation barrier.