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References: <20240215160136.1256084-1-alejandro.j.jimenez@oracle.com>
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From: Paolo Bonzini <pbonzini@redhat.com>
Date: Tue, 16 Apr 2024 21:53:21 +0200
Message-ID: <CABgObfZ6Q0t+J7=-BfZz4y9fDUtmJzt_RSyQ43LCg0KMpYC3+g@mail.gmail.com>
Subject: Re: [RFC 1/3] x86: KVM: stats: Add a stat to report status of APICv inhibition
To: Sean Christopherson <seanjc@google.com>
Cc: Alejandro Jimenez <alejandro.j.jimenez@oracle.com>, kvm@vger.kernel.org, 
	linux-kernel@vger.kernel.org, joao.m.martins@oracle.com, 
	boris.ostrovsky@oracle.com, mark.kanda@oracle.com, 
	suravee.suthikulpanit@amd.com, mlevitsk@redhat.com
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On Tue, Apr 16, 2024 at 8:19=E2=80=AFPM Sean Christopherson <seanjc@google.=
com> wrote:
>
> > +     u64 apicv_inhibited;
>
> Tracking the negative is odd, i.e. if we add a stat, KVM should probably =
track
> if APICv is fully enabled, not if it's inhibited.
>
> This also should be a boolean, not a u64.  Precisely enumerating _why_ AP=
ICv is
> inhibited is firmly in debug territory, i.e. not in scope for "official" =
stats.

It is a boolean, but stats are all u64 in the file and the contents of
the file map the stats struct directly. See for example the existing
'u64 guest_mode".

Paolo