Re: [PATCH v2 1/2] KVM: s390: add stat counter for shadow gmap events

[Janosch Frank <frankja@linux.ibm.com>]

On 8/1/23 13:48, Nico Boehr wrote:
> Quoting David Hildenbrand (2023-07-27 09:37:21)
> [...]
>>> diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
>>> index 2bbc3d54959d..d35e03e82d3d 100644
>>> --- a/arch/s390/include/asm/kvm_host.h
>>> +++ b/arch/s390/include/asm/kvm_host.h
>>> @@ -777,6 +777,12 @@ struct kvm_vm_stat {
>>>        u64 inject_service_signal;
>>>        u64 inject_virtio;
>>>        u64 aen_forward;
>>> +     u64 gmap_shadow_acquire;
>>> +     u64 gmap_shadow_r1_te;
>>> +     u64 gmap_shadow_r2_te;
>>> +     u64 gmap_shadow_r3_te;
>>> +     u64 gmap_shadow_sg_te;
>>> +     u64 gmap_shadow_pg_te;
>>
>> Is "te" supposed to stand for "table entry" ?
> 
> Yes.
> 
>> If so, I'd suggest to just call this gmap_shadow_pg_entry etc.
> 
> Janosch, since you suggested the current naming, are you OK with _entry?

Sure

> 
> [...]
>>> diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
>>> index 8d6b765abf29..beb3be037722 100644
>>> --- a/arch/s390/kvm/vsie.c
>>> +++ b/arch/s390/kvm/vsie.c
>>> @@ -1221,6 +1221,7 @@ static int acquire_gmap_shadow(struct kvm_vcpu *vcpu,
>>>        if (IS_ERR(gmap))
>>>                return PTR_ERR(gmap);
>>>        gmap->private = vcpu->kvm;
>>> +     vcpu->kvm->stat.gmap_shadow_acquire++;
>>
>>
>> Do you rather want to have events for
>>
>> gmap_shadow_reuse (if gmap_shadow_valid() succeeded in that function)
>> gmap_shadow_create (if we have to create a new one via gmap_shadow)
>>
>> ?
> 
> Yeah, good suggestion. I'll add that.