[PATCH v6 05/16] KVM: x86/pmu: Introduce the ctrl_mask value for fixed counter

From: Like Xu
Date: Mon May 10 2021 - 22:43:28 EST


The mask value of fixed counter control register should be dynamic
adjusted with the number of fixed counters. This patch introduces a
variable that includes the reserved bits of fixed counter control
registers. This is needed for later Ice Lake fixed counter changes.

Co-developed-by: Luwei Kang <luwei.kang@xxxxxxxxx>
Signed-off-by: Luwei Kang <luwei.kang@xxxxxxxxx>
Signed-off-by: Like Xu <like.xu@xxxxxxxxxxxxxxx>
---
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/kvm/vmx/pmu_intel.c | 6 +++++-
2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 55efbacfc244..49b421bd3dd8 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -457,6 +457,7 @@ struct kvm_pmu {
unsigned nr_arch_fixed_counters;
unsigned available_event_types;
u64 fixed_ctr_ctrl;
+ u64 fixed_ctr_ctrl_mask;
u64 global_ctrl;
u64 global_status;
u64 global_ovf_ctrl;
diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c
index d9dbebe03cae..ac7fe714e6c1 100644
--- a/arch/x86/kvm/vmx/pmu_intel.c
+++ b/arch/x86/kvm/vmx/pmu_intel.c
@@ -400,7 +400,7 @@ static int intel_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
case MSR_CORE_PERF_FIXED_CTR_CTRL:
if (pmu->fixed_ctr_ctrl == data)
return 0;
- if (!(data & 0xfffffffffffff444ull)) {
+ if (!(data & pmu->fixed_ctr_ctrl_mask)) {
reprogram_fixed_counters(pmu, data);
return 0;
}
@@ -470,6 +470,7 @@ static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
struct kvm_cpuid_entry2 *entry;
union cpuid10_eax eax;
union cpuid10_edx edx;
+ int i;

pmu->nr_arch_gp_counters = 0;
pmu->nr_arch_fixed_counters = 0;
@@ -477,6 +478,7 @@ static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
pmu->counter_bitmask[KVM_PMC_FIXED] = 0;
pmu->version = 0;
pmu->reserved_bits = 0xffffffff00200000ull;
+ pmu->fixed_ctr_ctrl_mask = ~0ull;

entry = kvm_find_cpuid_entry(vcpu, 0xa, 0);
if (!entry)
@@ -511,6 +513,8 @@ static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
((u64)1 << edx.split.bit_width_fixed) - 1;
}

+ for (i = 0; i < pmu->nr_arch_fixed_counters; i++)
+ pmu->fixed_ctr_ctrl_mask &= ~(0xbull << (i * 4));
pmu->global_ctrl = ((1ull << pmu->nr_arch_gp_counters) - 1) |
(((1ull << pmu->nr_arch_fixed_counters) - 1) << INTEL_PMC_IDX_FIXED);
pmu->global_ctrl_mask = ~pmu->global_ctrl;
--
2.31.1