[PATCH v2 1/5] KVM: x86/pmu: Add base address parameter for get_fixed_pmc function

From: Luwei Kang
Date: Thu Mar 19 2020 - 02:35:44 EST


PEBS output to Inte PT feature introduces some new
MSRs(MSR_RELOAD_FIXED_CTRx) for fixed function counters that using for
autoload the present value after writing out a PEBS event.

Introduce a base MSRs address parameter to make this function can get
kvm performance monitor counter structure by MSR_RELOAD_FIXED_CTRx
registers.

Signed-off-by: Luwei Kang <luwei.kang@xxxxxxxxx>
---
arch/x86/kvm/pmu.h | 5 ++---
arch/x86/kvm/vmx/pmu_intel.c | 16 ++++++++++------
2 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kvm/pmu.h b/arch/x86/kvm/pmu.h
index 9de6ef1..d640628 100644
--- a/arch/x86/kvm/pmu.h
+++ b/arch/x86/kvm/pmu.h
@@ -117,10 +117,9 @@ static inline struct kvm_pmc *get_gp_pmc(struct kvm_pmu *pmu, u32 msr,
}

/* returns fixed PMC with the specified MSR */
-static inline struct kvm_pmc *get_fixed_pmc(struct kvm_pmu *pmu, u32 msr)
+static inline struct kvm_pmc *get_fixed_pmc(struct kvm_pmu *pmu,
+ u32 msr, u32 base)
{
- int base = MSR_CORE_PERF_FIXED_CTR0;
-
if (msr >= base && msr < base + pmu->nr_arch_fixed_counters) {
u32 index = array_index_nospec(msr - base,
pmu->nr_arch_fixed_counters);
diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c
index 6a0eef3..2db9b9e 100644
--- a/arch/x86/kvm/vmx/pmu_intel.c
+++ b/arch/x86/kvm/vmx/pmu_intel.c
@@ -43,7 +43,8 @@ static void reprogram_fixed_counters(struct kvm_pmu *pmu, u64 data)
u8 old_ctrl = fixed_ctrl_field(pmu->fixed_ctr_ctrl, i);
struct kvm_pmc *pmc;

- pmc = get_fixed_pmc(pmu, MSR_CORE_PERF_FIXED_CTR0 + i);
+ pmc = get_fixed_pmc(pmu, MSR_CORE_PERF_FIXED_CTR0 + i,
+ MSR_CORE_PERF_FIXED_CTR0);

if (old_ctrl == new_ctrl)
continue;
@@ -135,7 +136,8 @@ static struct kvm_pmc *intel_pmc_idx_to_pmc(struct kvm_pmu *pmu, int pmc_idx)
else {
u32 idx = pmc_idx - INTEL_PMC_IDX_FIXED;

- return get_fixed_pmc(pmu, idx + MSR_CORE_PERF_FIXED_CTR0);
+ return get_fixed_pmc(pmu, idx + MSR_CORE_PERF_FIXED_CTR0,
+ MSR_CORE_PERF_FIXED_CTR0);
}
}

@@ -196,7 +198,7 @@ static bool intel_is_valid_msr(struct kvm_vcpu *vcpu, u32 msr)
default:
ret = get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0) ||
get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0) ||
- get_fixed_pmc(pmu, msr);
+ get_fixed_pmc(pmu, msr, MSR_CORE_PERF_FIXED_CTR0);
break;
}

@@ -236,7 +238,7 @@ static struct kvm_pmc *intel_msr_idx_to_pmc(struct kvm_vcpu *vcpu, u32 msr)
struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
struct kvm_pmc *pmc;

- pmc = get_fixed_pmc(pmu, msr);
+ pmc = get_fixed_pmc(pmu, msr, MSR_CORE_PERF_FIXED_CTR0);
pmc = pmc ? pmc : get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0);
pmc = pmc ? pmc : get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0);

@@ -278,7 +280,8 @@ static int intel_pmu_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *data)
u64 val = pmc_read_counter(pmc);
*data = val & pmu->counter_bitmask[KVM_PMC_GP];
return 0;
- } else if ((pmc = get_fixed_pmc(pmu, msr))) {
+ } else if ((pmc = get_fixed_pmc(pmu, msr,
+ MSR_CORE_PERF_FIXED_CTR0))) {
u64 val = pmc_read_counter(pmc);
*data = val & pmu->counter_bitmask[KVM_PMC_FIXED];
return 0;
@@ -354,7 +357,8 @@ static int intel_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
data = (s64)(s32)data;
pmc->counter += data - pmc_read_counter(pmc);
return 0;
- } else if ((pmc = get_fixed_pmc(pmu, msr))) {
+ } else if ((pmc = get_fixed_pmc(pmu, msr,
+ MSR_CORE_PERF_FIXED_CTR0))) {
pmc->counter += data - pmc_read_counter(pmc);
return 0;
} else if ((pmc = get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0))) {
--
1.8.3.1