Re: [RFC 2/2] x86, vdso, pvclock: Simplify and speed up the vdso pvclock reader

From: Paolo Bonzini
Date: Tue Jan 06 2015 - 03:40:21 EST




On 05/01/2015 20:17, Marcelo Tosatti wrote:
> But there is no guarantee that vCPU-N has updated its pvti when
> vCPU-M resumes guest instruction execution.

You're right.

> So the cost this patch removes is mainly from __getcpu (==RDTSCP?) ?
> Perhaps you can use Gleb's idea to stick vcpu id into version field ?

Or just replace __getcpu with rdtscp.

Paolo
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