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

From: Like Xu
Date: Fri Mar 10 2023 - 05:54:39 EST


From: Like Xu <likexu@xxxxxxxxxxx>

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@xxxxxxxxxxx>
---
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