Re: [PATCH 3/3] KVM: s390: clear kicked_mask if not idle after set

Halil Pasic
2021-10-20T10:45:25Z

On Wed, 20 Oct 2021 12:31:19 +0200
Christian Borntraeger <borntraeger@de.ibm.com> wrote:

> > Before releasing something like this, where none of us is sure if
> > it really saves cpu cost, I'd prefer to run some measurement with
> > the whole kicked_mask logic removed and to compare the number of
> > vcpu wake ups with the number of interrupts to be processed by
> > the gib alert mechanism in a slightly over committed host while
> > driving with Matthews test load.
>
> But I think patch 1 and 2 can go immediately as they measurably or
> testable fix things. Correct?

I think so as well. And if patch 3 is going to be dropped, I would
really like to keep the unconditional clear in kvm_arch_vcpu_runnable(),
as my analysis in the discussion points out: I think it can save us
form trouble this patch is trying to address.

Regards,
Halil