linux-kernel - [PATCH 2/5] KVM: x86/pmu: Add a helper to check if pmc has PEBS mode enabled

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Message-Id: <20230310105346.12302-3-likexu@tencent.com>
Date:   Fri, 10 Mar 2023 18:53:43 +0800
From:   Like Xu <like.xu.linux@...il.com>
To:     Sean Christopherson <seanjc@...gle.com>
Cc:     Paolo Bonzini <pbonzini@...hat.com>,
        Ravi Bangoria <ravi.bangoria@....com>, kvm@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: [PATCH 2/5] KVM: x86/pmu: Add a helper to check if pmc has PEBS mode enabled

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

Add a helper to check if pmc has PEBS mode enabled so that more new
code may reuse this part and opportunistically drop a pmu reference.

No functional change intended.

Signed-off-by: Like Xu <likexu@...cent.com>
---
 arch/x86/kvm/pmu.c | 3 +--
 arch/x86/kvm/pmu.h | 7 +++++++
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
index d1c89a6625a0..01a6b7ffa9b1 100644
--- a/arch/x86/kvm/pmu.c
+++ b/arch/x86/kvm/pmu.c
@@ -191,7 +191,6 @@ static int pmc_reprogram_counter(struct kvm_pmc *pmc, u32 type, u64 config,
 				 bool exclude_user, bool exclude_kernel,
 				 bool intr)
 {
-	struct kvm_pmu *pmu = pmc_to_pmu(pmc);
 	struct perf_event *event;
 	struct perf_event_attr attr = {
 		.type = type,
@@ -203,7 +202,7 @@ static int pmc_reprogram_counter(struct kvm_pmc *pmc, u32 type, u64 config,
 		.exclude_kernel = exclude_kernel,
 		.config = config,
 	};
-	bool pebs = test_bit(pmc->idx, (unsigned long *)&pmu->pebs_enable);
+	bool pebs = pebs_is_enabled(pmc);
 
 	attr.sample_period = get_sample_period(pmc, pmc->counter);
 
diff --git a/arch/x86/kvm/pmu.h b/arch/x86/kvm/pmu.h
index cff0651b030b..db4262fe8814 100644
--- a/arch/x86/kvm/pmu.h
+++ b/arch/x86/kvm/pmu.h
@@ -189,6 +189,13 @@ static inline void kvm_pmu_request_counter_reprogram(struct kvm_pmc *pmc)
 	kvm_make_request(KVM_REQ_PMU, pmc->vcpu);
 }
 
+static inline bool pebs_is_enabled(struct kvm_pmc *pmc)
+{
+	struct kvm_pmu *pmu = pmc_to_pmu(pmc);
+
+	return test_bit(pmc->idx, (unsigned long *)&pmu->pebs_enable);
+}
+
 void kvm_pmu_deliver_pmi(struct kvm_vcpu *vcpu);
 void kvm_pmu_handle_event(struct kvm_vcpu *vcpu);
 int kvm_pmu_rdpmc(struct kvm_vcpu *vcpu, unsigned pmc, u64 *data);
-- 
2.39.2