Re: [PATCH v6 7/7] KVM: x86: hyperv: implement PV IPI send hypercalls

2018-10-01 Thread Vitaly Kuznetsov
Paolo Bonzini writes: > On 01/10/2018 18:20, Vitaly Kuznetsov wrote: >> Paolo Bonzini writes: >> >>> On 27/09/2018 13:07, Roman Kagan wrote: >> ... I must say that now it looks even more tempting to follow the same pattern as your kvm_hv_flush_tlb: define a function that would

Re: [PATCH v6 7/7] KVM: x86: hyperv: implement PV IPI send hypercalls

2018-10-01 Thread Vitaly Kuznetsov
Paolo Bonzini writes: > On 01/10/2018 18:20, Vitaly Kuznetsov wrote: >> Paolo Bonzini writes: >> >>> On 27/09/2018 13:07, Roman Kagan wrote: >> ... I must say that now it looks even more tempting to follow the same pattern as your kvm_hv_flush_tlb: define a function that would

Re: [PATCH v6 7/7] KVM: x86: hyperv: implement PV IPI send hypercalls

2018-10-01 Thread Paolo Bonzini
On 01/10/2018 18:20, Vitaly Kuznetsov wrote: > Paolo Bonzini writes: > >> On 27/09/2018 13:07, Roman Kagan wrote: > ... >>> >>> I must say that now it looks even more tempting to follow the same >>> pattern as your kvm_hv_flush_tlb: define a function that would call >>> kvm_apic_set_irq() on all

Re: [PATCH v6 7/7] KVM: x86: hyperv: implement PV IPI send hypercalls

2018-10-01 Thread Paolo Bonzini
On 01/10/2018 18:20, Vitaly Kuznetsov wrote: > Paolo Bonzini writes: > >> On 27/09/2018 13:07, Roman Kagan wrote: > ... >>> >>> I must say that now it looks even more tempting to follow the same >>> pattern as your kvm_hv_flush_tlb: define a function that would call >>> kvm_apic_set_irq() on all

Re: [PATCH v6 7/7] KVM: x86: hyperv: implement PV IPI send hypercalls

2018-10-01 Thread Vitaly Kuznetsov
Paolo Bonzini writes: > On 27/09/2018 13:07, Roman Kagan wrote: ... >> >> I must say that now it looks even more tempting to follow the same >> pattern as your kvm_hv_flush_tlb: define a function that would call >> kvm_apic_set_irq() on all vcpus in a mask (optimizing the all-set case >> with a

Re: [PATCH v6 7/7] KVM: x86: hyperv: implement PV IPI send hypercalls

2018-10-01 Thread Vitaly Kuznetsov
Paolo Bonzini writes: > On 27/09/2018 13:07, Roman Kagan wrote: ... >> >> I must say that now it looks even more tempting to follow the same >> pattern as your kvm_hv_flush_tlb: define a function that would call >> kvm_apic_set_irq() on all vcpus in a mask (optimizing the all-set case >> with a

Re: [PATCH v6 7/7] KVM: x86: hyperv: implement PV IPI send hypercalls

2018-10-01 Thread Paolo Bonzini
On 27/09/2018 13:07, Roman Kagan wrote: > On Wed, Sep 26, 2018 at 07:02:59PM +0200, Vitaly Kuznetsov wrote: >> Using hypercall for sending IPIs is faster because this allows to specify >> any number of vCPUs (even > 64 with sparse CPU set), the whole procedure >> will take only one VMEXIT. >> >>

Re: [PATCH v6 7/7] KVM: x86: hyperv: implement PV IPI send hypercalls

2018-10-01 Thread Paolo Bonzini
On 27/09/2018 13:07, Roman Kagan wrote: > On Wed, Sep 26, 2018 at 07:02:59PM +0200, Vitaly Kuznetsov wrote: >> Using hypercall for sending IPIs is faster because this allows to specify >> any number of vCPUs (even > 64 with sparse CPU set), the whole procedure >> will take only one VMEXIT. >> >>

Re: [PATCH v6 7/7] KVM: x86: hyperv: implement PV IPI send hypercalls

2018-09-27 Thread Roman Kagan
On Wed, Sep 26, 2018 at 07:02:59PM +0200, Vitaly Kuznetsov wrote: > Using hypercall for sending IPIs is faster because this allows to specify > any number of vCPUs (even > 64 with sparse CPU set), the whole procedure > will take only one VMEXIT. > > Current Hyper-V TLFS (v5.0b) claims that

Re: [PATCH v6 7/7] KVM: x86: hyperv: implement PV IPI send hypercalls

2018-09-27 Thread Roman Kagan
On Wed, Sep 26, 2018 at 07:02:59PM +0200, Vitaly Kuznetsov wrote: > Using hypercall for sending IPIs is faster because this allows to specify > any number of vCPUs (even > 64 with sparse CPU set), the whole procedure > will take only one VMEXIT. > > Current Hyper-V TLFS (v5.0b) claims that