Re: [PATCH v2 4/7] KVM: x86: Copy kvm_pmu_ops by value to eliminate layer of indirection

From: Sean Christopherson <seanjc@google.com>
To: Like Xu <like.xu.linux@gmail.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>,
	kvm@vger.kernel.org, Wanpeng Li <wanpengli@tencent.com>,
	Jim Mattson <jmattson@google.com>,
	Vitaly Kuznetsov <vkuznets@redhat.com>,
	Joerg Roedel <joro@8bytes.org>,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 4/7] KVM: x86: Copy kvm_pmu_ops by value to eliminate layer of indirection
Date: Wed, 8 Dec 2021 18:10:25 +0000	[thread overview]
Message-ID: <YbD1ETLLpf4uKPWY@google.com> (raw)
In-Reply-To: <20211108111032.24457-5-likexu@tencent.com>

On Mon, Nov 08, 2021, Like Xu wrote:
> From: Like Xu <likexu@tencent.com>
> 
> Replace the kvm_pmu_ops pointer in common x86 with an instance of the
> struct to save one pointer dereference when invoking functions. Copy the
> struct by value to set the ops during kvm_init().
> 
> Signed-off-by: Like Xu <likexu@tencent.com>
> ---
>  arch/x86/kvm/pmu.c | 41 ++++++++++++++++++++++-------------------
>  arch/x86/kvm/pmu.h |  4 +++-
>  arch/x86/kvm/x86.c |  1 +
>  3 files changed, 26 insertions(+), 20 deletions(-)
> 
> diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
> index aa6ac9c7aff2..353989bf0102 100644
> --- a/arch/x86/kvm/pmu.c
> +++ b/arch/x86/kvm/pmu.c
> @@ -47,6 +47,9 @@
>   *        * AMD:   [0 .. AMD64_NUM_COUNTERS-1] <=> gp counters
>   */
>  
> +struct kvm_pmu_ops kvm_pmu_ops __read_mostly;
> +EXPORT_SYMBOL_GPL(kvm_pmu_ops);

This export isn't necessary.