On 12/07/16 03:26, David Matlack wrote: > On Mon, Jul 11, 2016 at 10:07 AM, Paolo Bonzini <pbonz...@redhat.com> wrote: >> >> On 11/07/2016 18:57, David Matlack wrote: >>> On Mon, Jul 11, 2016 at 12:08 AM, Suraj Jitindar Singh >>> <sjitindarsi...@gmail.com> wrote: >>>> This patch introduces new halt polling functionality into the kvm_hv kernel >>>> module. When a vcore is idle it will poll for some period of time before >>>> scheduling itself out. >>> Is there any way to reuse the existing halt-polling code? Having two >>> copies risks them diverging over time. >> s/risks/guarantees/ :( >> >> Unfortunately, handling of the hardware threads in KVM PPC is a mess, >> and I don't think it's possible to remove the duplication. > Ah, ok. That's a shame.
It's definitely not ideal having this code duplicated, although we have the issue that on PPC we only poll once all of the vcpus on a vcore have ceded and need to retain a reference to that vcore. Additionally we only actually do this in HV code, on the KVM PR version we call the generic halt-polling code which doesn't know about vcores. I don't see an easy way to use the existing function. > >> Paolo _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
