linux-kernel - [PATCH] KVM: x86/pmu: Avoid ternary operator by directly referring to counters->type

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Message-Id: <20221205113718.1487-1-likexu@tencent.com>
Date:   Mon,  5 Dec 2022 19:37:18 +0800
From:   Like Xu <like.xu.linux@...il.com>
To:     Sean Christopherson <seanjc@...gle.com>,
        Paolo Bonzini <pbonzini@...hat.com>
Cc:     kvm@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: [PATCH] KVM: x86/pmu: Avoid ternary operator by directly referring to counters->type

From: Like Xu <likexu@...cent.com>

In either case, the counters will point to fixed or gp pmc array, and
taking advantage of the C pointer, it's reasonable to use an almost known
mem load operation directly without disturbing the branch predictor.

Signed-off-by: Like Xu <likexu@...cent.com>
---
 arch/x86/kvm/vmx/pmu_intel.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c
index e5cec07ca8d9..28b0a784f6e9 100644
--- a/arch/x86/kvm/vmx/pmu_intel.c
+++ b/arch/x86/kvm/vmx/pmu_intel.c
@@ -142,7 +142,7 @@ static struct kvm_pmc *intel_rdpmc_ecx_to_pmc(struct kvm_vcpu *vcpu,
 	}
 	if (idx >= num_counters)
 		return NULL;
-	*mask &= pmu->counter_bitmask[fixed ? KVM_PMC_FIXED : KVM_PMC_GP];
+	*mask &= pmu->counter_bitmask[counters->type];
 	return &counters[array_index_nospec(idx, num_counters)];
 }
 
-- 
2.38.1