[PATCH v2 05/12] KVM: x86/pmu: Drop "u8 ctrl, int idx" for reprogram_fixed_counter()

From: Like Xu
Date: Wed Mar 02 2022 - 06:14:44 EST


From: Like Xu <likexu@xxxxxxxxxxx>

Since afrer reprogram_fixed_counter() is called, it's bound to assign
the requested fixed_ctr_ctrl to pmu->fixed_ctr_ctrl, this assignment step
can be moved forward (the stale value for diff is saved extra early),
thus simplifying the passing of parameters.

No functional change intended.

Signed-off-by: Like Xu <likexu@xxxxxxxxxxx>
---
arch/x86/kvm/pmu.c | 13 ++++++-------
arch/x86/kvm/pmu.h | 2 +-
arch/x86/kvm/vmx/pmu_intel.c | 16 ++++++++--------
3 files changed, 15 insertions(+), 16 deletions(-)

diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
index 7b8a5f973a63..282e6e859c46 100644
--- a/arch/x86/kvm/pmu.c
+++ b/arch/x86/kvm/pmu.c
@@ -260,8 +260,11 @@ void reprogram_gp_counter(struct kvm_pmc *pmc)
}
EXPORT_SYMBOL_GPL(reprogram_gp_counter);

-void reprogram_fixed_counter(struct kvm_pmc *pmc, u8 ctrl, int idx)
+void reprogram_fixed_counter(struct kvm_pmc *pmc)
{
+ struct kvm_pmu *pmu = pmc_to_pmu(pmc);
+ int idx = pmc->idx - INTEL_PMC_IDX_FIXED;
+ u8 ctrl = fixed_ctrl_field(pmu->fixed_ctr_ctrl, idx);
unsigned en_field = ctrl & 0x3;
bool pmi = ctrl & 0x8;

@@ -291,12 +294,8 @@ void reprogram_counter(struct kvm_pmc *pmc)
{
if (pmc_is_gp(pmc))
reprogram_gp_counter(pmc);
- else {
- int idx = pmc->idx - INTEL_PMC_IDX_FIXED;
- u8 ctrl = fixed_ctrl_field(pmc_to_pmu(pmc)->fixed_ctr_ctrl, idx);
-
- reprogram_fixed_counter(pmc, ctrl, idx);
- }
+ else
+ reprogram_fixed_counter(pmc);
}
EXPORT_SYMBOL_GPL(reprogram_counter);

diff --git a/arch/x86/kvm/pmu.h b/arch/x86/kvm/pmu.h
index 4db50c290c62..70a982c3cdad 100644
--- a/arch/x86/kvm/pmu.h
+++ b/arch/x86/kvm/pmu.h
@@ -141,7 +141,7 @@ static inline u64 get_sample_period(struct kvm_pmc *pmc, u64 counter_value)
}

void reprogram_gp_counter(struct kvm_pmc *pmc);
-void reprogram_fixed_counter(struct kvm_pmc *pmc, u8 ctrl, int fixed_idx);
+void reprogram_fixed_counter(struct kvm_pmc *pmc);
void reprogram_counter(struct kvm_pmc *pmc);

void kvm_pmu_deliver_pmi(struct kvm_vcpu *vcpu);
diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c
index 2eefde7e4b1a..3ddbfdd16cd0 100644
--- a/arch/x86/kvm/vmx/pmu_intel.c
+++ b/arch/x86/kvm/vmx/pmu_intel.c
@@ -37,23 +37,23 @@ static int fixed_pmc_events[] = {1, 0, 7};

static void reprogram_fixed_counters(struct kvm_pmu *pmu, u64 data)
{
+ struct kvm_pmc *pmc;
+ u8 old_fixed_ctr_ctrl = pmu->fixed_ctr_ctrl;
int i;

+ pmu->fixed_ctr_ctrl = data;
for (i = 0; i < pmu->nr_arch_fixed_counters; i++) {
u8 new_ctrl = fixed_ctrl_field(data, i);
- 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);
+ u8 old_ctrl = fixed_ctrl_field(old_fixed_ctr_ctrl, i);

if (old_ctrl == new_ctrl)
continue;

- __set_bit(INTEL_PMC_IDX_FIXED + i, pmu->pmc_in_use);
- reprogram_fixed_counter(pmc, new_ctrl, i);
- }
+ pmc = get_fixed_pmc(pmu, MSR_CORE_PERF_FIXED_CTR0 + i);

- pmu->fixed_ctr_ctrl = data;
+ __set_bit(INTEL_PMC_IDX_FIXED + i, pmu->pmc_in_use);
+ reprogram_fixed_counter(pmc);
+ }
}

static struct kvm_pmc *intel_pmc_idx_to_pmc(struct kvm_pmu *pmu, int pmc_idx)
--
2.35.1