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Date: Thu, 11 Apr 2024 13:57:22 -0700
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Message-ID: <ZhhOsvPxhEQl9YmX@google.com>
Subject: Re: [RFC PATCH 12/41] KVM: x86/pmu: Plumb through passthrough PMU to
 vcpu for Intel CPUs
From: Sean Christopherson <seanjc@google.com>
To: Xiong Zhang <xiong.y.zhang@linux.intel.com>
Cc: pbonzini@redhat.com, peterz@infradead.org, mizhang@google.com, 
	kan.liang@intel.com, zhenyuw@linux.intel.com, dapeng1.mi@linux.intel.com, 
	jmattson@google.com, kvm@vger.kernel.org, linux-perf-users@vger.kernel.org, 
	linux-kernel@vger.kernel.org, zhiyuan.lv@intel.com, eranian@google.com, 
	irogers@google.com, samantha.alt@intel.com, like.xu.linux@gmail.com, 
	chao.gao@intel.com, Xiong Zhang <xiong.y.zhang@intel.com>
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On Fri, Jan 26, 2024, Xiong Zhang wrote:
> From: Mingwei Zhang <mizhang@google.com>
> 
> Plumb through passthrough PMU setting from kvm->arch into kvm_pmu on each
> vcpu created. Note that enabling PMU is decided by VMM when it sets the
> CPUID bits exposed to guest VM. So plumb through the enabling for each pmu
> in intel_pmu_refresh().

As stated in the previous patch, even the most naive implementation can be:

static inline bool is_passthrough_pmu_enabled(struct kvm_vcpu *vcpu)
{
	return enable_passthrough_pmu && vcpu_to_pmu(vcpu)->version;
}