Re: [libvirt] [PATCH 3/3] qemu: Prohibit chaning affinity of domain process if placement is 'auto'

On 10/24/2012 03:45 PM, Osier Yang wrote: > On 2012年10月24日 21:38, Martin Kletzander wrote: >> On 10/24/2012 12:00 PM, Osier Yang wrote: >>> On one hand, numad probably will manage the affinity of domain process >>> dynamically in future. On the other hand, even numad won't manage it, >> >> s/even/even if/ >> >>> it still could confusion. Let's make things simpler enough to avoid >> >> s/could/could cause/ >> >>> the lair for now. >>> --- >>> src/qemu/qemu_driver.c | 7 +++++++ >>> 1 files changed, 7 insertions(+), 0 deletions(-) >>> >>> diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c >>> index 8af316f..254f191 100644 >>> --- a/src/qemu/qemu_driver.c >>> +++ b/src/qemu/qemu_driver.c >>> @@ -4204,6 +4204,13 @@ qemudDomainPinEmulator(virDomainPtr dom, >>> goto cleanup; >>> } >>> >>> + if (vm->def->placement_mode == >>> VIR_DOMAIN_CPU_PLACEMENT_MODE_AUTO) { >>> + virReportError(VIR_ERR_OPERATION_INVALID, "%s", >>> + _("Changing affinity for emulator thread >>> dynamically " >>> + "is not allowed when CPU placement is >>> 'auto'")); >>> + goto cleanup; >>> + } >>> + >>> if (virDomainLiveConfigHelperMethod(driver->caps, vm,&flags, >>> &persistentDef)< 0) >>> goto cleanup; >>> >> >> We should unify if the vcpu pinning is only meant for starting the >> domain or if it's mandatory for the whole time domain is running. It is >> possible now to have auto placement and pin the vcpus while the domain >> is running. >> >> If we want to disable it for emulator threads, we should also do it for >> VCPU threads. > > IMO no need to disable for vCPU threads, as "auto" placement only > cares about the affinity of domain process, it might imply we should > change that, but now it is that. > > However, then decision whether we should do it at all >> should not be made by me. Anyone else has an opinion on that? >> >> Martin > Of course, sorry, my bad. ACK, of course.