Re: [PATCH v5 05/15] KVM: s390: unify pending_irqs() and pending_irqs_no_gisa()

[Michael Mueller]

On 20.12.18 16:43, pierre morel wrote:
> Le 12/20/18 Ã 13:33, Michael Mueller a ÃcritÂ:
> > On 20.12.18 13:21, Cornelia Huck wrote:
> > > On Thu, 20 Dec 2018 12:49:56 +0100
> > > Michael Mueller <mimu@xxxxxxxxxxxxx> wrote:
> > >
> > > > On 20.12.18 12:06, Cornelia Huck wrote:
> > > > > On Wed, 19 Dec 2018 20:17:46 +0100
> > > > > Michael Mueller <mimu@xxxxxxxxxxxxx> wrote:
> > > > > > Use a single function with parameter irq_flags to differentiate
> > > > > > between cases.
> ...snip
> > > > > > ÂÂ }
> > > > > > -static inline unsigned long pending_irqs_no_gisa(struct kvm_vcpu 
> > > > > > *vcpu)
> > > > > > +static inline unsigned long pending_irqs(struct kvm_vcpu *vcpu, 
> > > > > > u16 irq_flags)
> > > > >
> > > > > Any deeper reason why this is a u16? 16 bits should be enough for
> > > > > everyone? :)
> > > >
> > > > I want to use the 8 bits for the IRQ type and the other 8 for 
> > > > additional
> > > > controls, see: "KVM: s390: restore IAM in get_ipm() when IPM is clean"
> > >
> > > Still need to look at that patch, but my question mainly was "why only
> > > 16 bits"? I would think making this local variable larger is cheap.
>
> +1
>
> > I will enlarge the flag mask to u32 with 16 bits for the IRQ types then.
>
> AFAIK CPU generally work better with int (or long)
> Is there any hardware reason to restrict the size?

It's already changed to 4 bytes

> > > > > > ÂÂ {
> > > > > > -ÂÂÂ return vcpu->kvm->arch.float_int.pending_irqs |
> > > > > > -ÂÂÂÂÂÂÂ vcpu->arch.local_int.pending_irqs;
> > > > > > -}