[PATCH v3 14/18] KVM: x86/pmu: Factor out fixed counter control bit calculation

[Zide Chen <zide.chen@intel.com>]

Rename intel_pmu_enable_fixed_counter_bits() to
intel_pmu_fixed_ctrl_bits() and have it return the computed fixed
counter control mask instead of updating fixed_ctr_ctrl_rsvd directly.

Accumulate the desired fixed counter control bits during PMU setup and
apply them once in intel_pmu_refresh().

Move the helper earlier in the file so it can also be reused for
upcoming ANYTHREAD_DEPRECATION emulation.

No functional change intended.

Signed-off-by: Zide Chen <zide.chen@intel.com>
Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
---
v2:
- New patch.
---
 arch/x86/kvm/vmx/pmu_intel.c | 32 +++++++++++++++++++-------------
 1 file changed, 19 insertions(+), 13 deletions(-)

diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c
index 37b34b588601..6bd7c8e03c14 100644
--- a/arch/x86/kvm/vmx/pmu_intel.c
+++ b/arch/x86/kvm/vmx/pmu_intel.c
@@ -55,6 +55,18 @@ static struct x86_pmu_lbr *vcpu_to_lbr_records(struct kvm_vcpu *vcpu)
 
 #pragma GCC poison to_vmx
 
+static u64 intel_pmu_fixed_ctrl_bits(struct kvm_pmu *pmu, u64 bits)
+{
+	unsigned long fixed_mask = kvm_fixed_pmc_mask(pmu);
+	u64 fixed_ctrl_bits = 0;
+	int i;
+
+	kvm_for_each_fixed_counter(i, fixed_mask)
+		fixed_ctrl_bits |= intel_fixed_bits_by_idx(i, bits);
+
+	return fixed_ctrl_bits;
+}
+
 static void reprogram_fixed_counters(struct kvm_pmu *pmu, u64 data)
 {
 	/*
@@ -537,20 +549,12 @@ static __always_inline u64 intel_get_fixed_pmc_eventsel(unsigned int index)
 	return eventsel;
 }
 
-static void intel_pmu_enable_fixed_counter_bits(struct kvm_pmu *pmu, u64 bits)
-{
-	unsigned long fixed_mask = kvm_fixed_pmc_mask(pmu);
-	int i;
-
-	kvm_for_each_fixed_counter(i, fixed_mask)
-		pmu->fixed_ctr_ctrl_rsvd &= ~intel_fixed_bits_by_idx(i, bits);
-}
-
 static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
 {
 	struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
 	struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
 	struct kvm_cpuid_entry2 *entry;
+	u64 fixed_enable_bits = 0;
 	union cpuid10_eax eax;
 	union cpuid10_edx edx;
 	u64 perf_capabilities;
@@ -643,9 +647,8 @@ static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
 					  kvm_pmu_cap.bit_width_fixed);
 	pmu->counter_bitmask[KVM_PMC_FIXED] = BIT_ULL(edx.split.bit_width_fixed) - 1;
 
-	intel_pmu_enable_fixed_counter_bits(pmu, INTEL_FIXED_0_KERNEL |
-						 INTEL_FIXED_0_USER |
-						 INTEL_FIXED_0_ENABLE_PMI);
+	fixed_enable_bits |= INTEL_FIXED_0_KERNEL | INTEL_FIXED_0_USER |
+			     INTEL_FIXED_0_ENABLE_PMI;
 
 	counter_rsvd = ~((u64)kvm_gp_pmc_mask(pmu) |
 			 ((u64)kvm_fixed_pmc_mask(pmu) << KVM_FIXED_PMC_BASE_IDX));
@@ -661,11 +664,14 @@ static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
 			pmu->pebs_enable_rsvd = counter_rsvd;
 			pmu->eventsel_rsvd &= ~ICL_EVENTSEL_ADAPTIVE;
 			pmu->pebs_data_cfg_rsvd = ~0xff00000full;
-			intel_pmu_enable_fixed_counter_bits(pmu, ICL_FIXED_0_ADAPTIVE);
+			fixed_enable_bits |= ICL_FIXED_0_ADAPTIVE;
 		} else {
 			pmu->pebs_enable_rsvd = ~(u64)kvm_gp_pmc_mask(pmu);
 		}
 	}
+
+	pmu->fixed_ctr_ctrl_rsvd &=
+		~intel_pmu_fixed_ctrl_bits(pmu, fixed_enable_bits);
 }
 
 static void intel_pmu_init(struct kvm_vcpu *vcpu)
-- 
2.56.0