linux-kernel - Re: [PATCH 13/18] KVM: x86/pmu: Open code pmc_event_is

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Message-ID: <ba9a19c0-c30a-44fa-bc21-7184422c937d@linux.intel.com>
Date: Wed, 6 Aug 2025 15:30:33 +0800
From: "Mi, Dapeng" <dapeng1.mi@...ux.intel.com>
To: Sean Christopherson <seanjc@...gle.com>,
 Paolo Bonzini <pbonzini@...hat.com>
Cc: kvm@...r.kernel.org, linux-kernel@...r.kernel.org, Xin Li
 <xin@...or.com>, Sandipan Das <sandipan.das@....com>
Subject: Re: [PATCH 13/18] KVM: x86/pmu: Open code pmc_event_is_allowed() in
 its callers


On 8/6/2025 3:05 AM, Sean Christopherson wrote:
> Open code pmc_event_is_allowed() in its callers, as kvm_pmu_trigger_event()
> only needs to check the event filter (both global and local enables are
> consulted outside of the loop).
>
> No functional change intended.
>
> Signed-off-by: Sean Christopherson <seanjc@...gle.com>
> ---
>  arch/x86/kvm/pmu.c | 12 ++++--------
>  1 file changed, 4 insertions(+), 8 deletions(-)
>
> diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
> index e73c2a44028b..a495ab5d0556 100644
> --- a/arch/x86/kvm/pmu.c
> +++ b/arch/x86/kvm/pmu.c
> @@ -491,12 +491,6 @@ static bool check_pmu_event_filter(struct kvm_pmc *pmc)
>  	return is_fixed_event_allowed(filter, pmc->idx);
>  }
>  
> -static bool pmc_event_is_allowed(struct kvm_pmc *pmc)
> -{
> -	return pmc_is_globally_enabled(pmc) && pmc_is_locally_enabled(pmc) &&
> -	       check_pmu_event_filter(pmc);
> -}
> -
>  static int reprogram_counter(struct kvm_pmc *pmc)
>  {
>  	struct kvm_pmu *pmu = pmc_to_pmu(pmc);
> @@ -507,7 +501,8 @@ static int reprogram_counter(struct kvm_pmc *pmc)
>  
>  	emulate_overflow = pmc_pause_counter(pmc);
>  
> -	if (!pmc_event_is_allowed(pmc))
> +	if (!pmc_is_globally_enabled(pmc) || !pmc_is_locally_enabled(pmc) ||
> +	    !check_pmu_event_filter(pmc))
>  		return 0;
>  
>  	if (emulate_overflow)
> @@ -974,7 +969,8 @@ static void kvm_pmu_trigger_event(struct kvm_vcpu *vcpu,
>  		return;
>  
>  	kvm_for_each_pmc(pmu, pmc, i, bitmap) {
> -		if (!pmc_event_is_allowed(pmc) || !cpl_is_matched(pmc))
> +		if (!pmc_is_globally_enabled(pmc) || !pmc_is_locally_enabled(pmc) ||
> +		    !check_pmu_event_filter(pmc) || !cpl_is_matched(pmc))
>  			continue;
>  
>  		kvm_pmu_incr_counter(pmc);

Reviewed-by: Dapeng Mi <dapeng1.mi@...ux.intel.com>