Messages in this thread | | | Date | Mon, 28 Mar 2022 14:51:21 +0000 | From | Sean Christopherson <> | Subject | Re: [PATCH] KVM: x86: optimize PKU branching in kvm_load_{guest|host}_xsave_state |
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On Mon, Mar 28, 2022, Jon Kohler wrote: > > > > On Mar 27, 2022, at 6:43 AM, Paolo Bonzini <pbonzini@redhat.com> wrote: > > > > On 3/26/22 02:37, Jon Kohler wrote: > >>>> Flip the ordering of the || condition so that XFEATURE_MASK_PKRU is > >>>> checked first, which when instrumented in our environment appeared > >>>> to be always true and less overall work than kvm_read_cr4_bits. > >>> > >>> If it's always true, then it should be checked last, not first. And if > >> Sean thanks for the review. This would be a left handed || short circuit, so > >> wouldn’t we want always true to be first? > > > > Yes. > > Ack, thanks.
Yeah, I lost track of whether it was a || or &&.
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