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Subject: Re: [PATCH] KVM: LAPIC: Recalculate apic map in batch
To:     Wanpeng Li <kernellwp@gmail.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>
Cc:     LKML <linux-kernel@vger.kernel.org>, kvm <kvm@vger.kernel.org>,
        Sean Christopherson <sean.j.christopherson@intel.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>
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 <CANRm+Cyx+J+YK8FzFBV8LRNPeCaXPc93vjFdpA0D_hA+wrpywQ@mail.gmail.com>
From:   Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <f433ff7e-72de-e2fd-5b71-a9ac92769c03@redhat.com>
Date:   Tue, 25 Feb 2020 09:07:01 +0100
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On 19/02/20 01:47, Wanpeng Li wrote:
>> An alternative idea: instead of making every caller return bool and
>> every call site handle the result (once) just add a
>> KVM_REQ_APIC_MAP_RECALC flag or a boolean flag to struct kvm. I
>> understand it may not be that easy as it sounds as we may be conunting
>> on valid mapping somewhere before we actually get to handiling
> Yes.
> 
>> KVM_REQ_APIC_MAP_RECALC but we may preserve *some*
>> recalculate_apic_map() calls (and make it reset KVM_REQ_APIC_MAP_RECALC).
> Paolo, keep the caller return bool or add a booleen flag to struct
> kvm, what do you think?

A third possibility: add an apic_map field to struct kvm_lapic, so that
you don't have to add bool return values everywhere.

Paolo