Re: [libvirt] [RFC] kvm: x86: export vCPU halted state to sysfs
On Fri, Feb 02, 2018 at 05:19:34PM +0100, Viktor Mihajlovski wrote:
On 02.02.2018 17:01, Luiz Capitulino wrote:
[...]
> o Make qemuDomainRefreshVcpuHalted() s390-only in libvirt. This
by
> itself fixes the original performance issue
We are normally trying to avoid architecture-specific code in libvirt
(not always successfully). We could omit the call, based on a QEMU
Capability derived from the presence of said flag. This would change the
libvirt-client side default to not report halted. A client can the still
request the value via a tbd libvirt flag. Which is what an s390-aware
management app would have to do...
The problem I see here is that the current semantics of the
"halted" field in QEMU is arch-specific, so either libvirt or
upper layers will necessarily need arch-specific code if they
want to support QEMU 2.11 or older.
--
Eduardo