Re: [PATCH v2 2/3] xen/sched: don't call sync_vcpu_execstate() in sched_unit_migrate_finish()

[Jan Beulich <jbeulich@xxxxxxxx>]

On 14.05.2020 16:21, Jürgen Groß wrote:
> On 14.05.20 15:57, Jan Beulich wrote:
>> On 11.05.2020 13:28, Juergen Gross wrote:
>>> With support of core scheduling sched_unit_migrate_finish() gained a
>>> call of sync_vcpu_execstate() as it was believed to be called as a
>>> result of vcpu migration in any case.
>>>
>>> In case of migrating a vcpu away from a physical cpu for a short period
>>> of time only this might not be true, so drop the call and let the lazy
>>> state syncing do its job.
>>
>> Replying here instead of on the patch 3 thread (and I'm sorry
>> for mixing up function names there): By saying "for a short
>> period of time only", do you imply without ever getting scheduled
>> on the new (temporary) CPU? If so, I think I understand this
>> change now, but then this could do with saying here. If not, I'm
>> afraid I'm still lost.
> 
> I'll change the commit message to:
> 
> ... for a short period of time only without ever being scheduled on the
> selected new cpu ...

And then
Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>
for both this one and patch 3 (ideally with the one unnecessary hunk
dropped).

Jan