linux-kernel - [PATCH 14/18] KVM: x86/pmu: Drop redundant check on PMC being globally enabled for emulation

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Message-ID: <20250805190526.1453366-15-seanjc@google.com>
Date: Tue,  5 Aug 2025 12:05:22 -0700
From: Sean Christopherson <seanjc@...gle.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>, 
	Dapeng Mi <dapeng1.mi@...ux.intel.com>, Sandipan Das <sandipan.das@....com>
Subject: [PATCH 14/18] KVM: x86/pmu: Drop redundant check on PMC being
 globally enabled for emulation

When triggering PMC events in response to emulation, drop the redundant
checks on a PMC being globally and locally enabled, as the passed in bitmap
contains only PMCs that are locally enabled (and counting the right event),
and the local copy of the bitmap has already been masked with global_ctrl.

No true functional change intended.

Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 arch/x86/kvm/pmu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
index a495ab5d0556..bdcd9c6f0ec0 100644
--- a/arch/x86/kvm/pmu.c
+++ b/arch/x86/kvm/pmu.c
@@ -969,7 +969,7 @@ static void kvm_pmu_trigger_event(struct kvm_vcpu *vcpu,
 		return;
 
 	kvm_for_each_pmc(pmu, pmc, i, bitmap) {
-		if (!pmc_is_globally_enabled(pmc) || !pmc_is_locally_enabled(pmc) ||
+		if (!pmc_is_locally_enabled(pmc) ||
 		    !check_pmu_event_filter(pmc) || !cpl_is_matched(pmc))
 			continue;
 
-- 
2.50.1.565.gc32cd1483b-goog