lkml.org 
[lkml]   [2012]   [May]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCHv4 3/5] kvm: host side for eoi optimization
    On Wed, May 16, 2012 at 10:07:58PM +0300, Michael S. Tsirkin wrote:
    > > This code is reached from kvm_cpu_get_interrupt(), but this function will
    > > not be called in above scenario.
    >
    > I think I see. So this shall fix it also makes code cleaner
    > (no -2 hack). Right? kvm_apic_has_interrupt is called correct?
    >
    > diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
    > index b4f7013..5a38e34 100644
    > --- a/arch/x86/kvm/lapic.c
    > +++ b/arch/x86/kvm/lapic.c
    > @@ -1273,8 +1273,12 @@ int kvm_apic_has_interrupt(struct kvm_vcpu *vcpu)
    > highest_irr = apic_find_highest_irr(apic);
    > if (highest_irr == -1)
    > return -1;
    > - if (((highest_irr & 0xF0) <= apic_get_reg(apic, APIC_PROCPRI)))
    > - return -2;
    > + /* Detect interrupt nesting and disable EOI optimization */
    > + if ((highest_irr & 0xF0) <= apic_get_reg(apic, APIC_PROCPRI)) {
    > + if (pv_eoi_enabled(vcpu))
    > + pv_eoi_clr_pending(vcpu);
    > + return -1;
    > + }
    > return highest_irr;
    > }
    >
    I do not like it. kvm_apic_has_interrupt() does not suppose to mutate
    state.

    > @@ -1306,10 +1310,6 @@ int kvm_get_apic_interrupt(struct kvm_vcpu *vcpu)
    > int vector = kvm_apic_has_interrupt(vcpu);
    > struct kvm_lapic *apic = vcpu->arch.apic;
    >
    > - /* Detect interrupt nesting and disable EOI optimization */
    > - if (pv_eoi_enabled(vcpu) && vector == -2)
    > - pv_eoi_clr_pending(vcpu);
    > -
    > if (vector < 0)
    > return -1;
    >

    --
    Gleb.


    \
     
     \ /
      Last update: 2012-05-17 09:41    [W:4.131 / U:0.024 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site