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Subject: Re: [PATCH 2/2] KVM: Scalable memslots implementation
To:     David Hildenbrand <david@redhat.com>,
        "Maciej S. Szmigiero" <mail@maciej.szmigiero.name>,
        Sean Christopherson <seanjc@google.com>
Cc:     Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Igor Mammedov <imammedo@redhat.com>,
        Marc Zyngier <maz@kernel.org>,
        James Morse <james.morse@arm.com>,
        Julien Thierry <julien.thierry.kdev@gmail.com>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        Huacai Chen <chenhuacai@kernel.org>,
        Aleksandar Markovic <aleksandar.qemu.devel@gmail.com>,
        Paul Mackerras <paulus@ozlabs.org>,
        Christian Borntraeger <borntraeger@de.ibm.com>,
        Janosch Frank <frankja@linux.ibm.com>,
        Cornelia Huck <cohuck@redhat.com>,
        Claudio Imbrenda <imbrenda@linux.ibm.com>,
        Joerg Roedel <joro@8bytes.org>, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org
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From:   Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <307603f3-52a8-7464-ba98-06cbe4ddd408@redhat.com>
Date:   Wed, 3 Feb 2021 14:46:41 +0100
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On 03/02/21 14:44, David Hildenbrand wrote:
> BTW: what are your thoughts regarding converting the rmap array on 
> x86-64 into some dynamic datastructre (xarray etc)? Has that already 
> been discussed?

Hasn't been discussed---as always, showing the code would be the best 
way to start a discussion. :)

However, note that the TDP MMU does not need an rmap at all.  Since that 
one is getting ready to become the default, the benefits of working on 
the rmap would be quite small and only affect nested virtualization.

Paolo