With per guest ID registers, PMUver settings from userspace
can be stored in its corresponding ID register.
No functional change intended.
Signed-off-by: Jing Zhang <jingzhangos@xxxxxxxxxx>
---
arch/arm64/include/asm/kvm_host.h | 11 ++++---
arch/arm64/kvm/arm.c | 6 ----
arch/arm64/kvm/id_regs.c | 51 +++++++++++++++++++++++++------
include/kvm/arm_pmu.h | 5 +--
4 files changed, 50 insertions(+), 23 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 283e1f30cec5..28448e53bbf3 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -244,6 +244,12 @@ struct kvm_arch {
#define KVM_ARCH_FLAG_VM_COUNTER_OFFSET 6
/* Timer PPIs made immutable */
#define KVM_ARCH_FLAG_TIMER_PPIS_IMMUTABLE 7
+ /*
+ * AA64DFR0_EL1.PMUver was set as ID_AA64DFR0_EL1_PMUVer_IMP_DEF
+ * or DFR0_EL1.PerfMon was set as ID_DFR0_EL1_PerfMon_IMPDEF from
+ * userspace for VCPUs without PMU.
+ */
+#define KVM_ARCH_FLAG_VCPU_HAS_IMP_DEF_PMU 8
unsigned long flags;
@@ -256,11 +262,6 @@ struct kvm_arch {
cpumask_var_t supported_cpus;
- struct {
- u8 imp:4;
- u8 unimp:4;
- } dfr0_pmuver;
-
/* Hypercall features firmware registers' descriptor */
struct kvm_smccc_features smccc_feat;
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 483c7377e092..48d738148e84 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -150,12 +150,6 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
kvm_arm_init_hypercalls(kvm);
kvm_arm_init_id_regs(kvm);
- /*
- * Initialise the default PMUver before there is a chance to
- * create an actual PMU.
- */
- kvm->arch.dfr0_pmuver.imp = kvm_arm_pmu_get_pmuver_limit();
-
return 0;
err_free_cpumask:
diff --git a/arch/arm64/kvm/id_regs.c b/arch/arm64/kvm/id_regs.c
index c6525efe8058..e92eacb0ad32 100644
--- a/arch/arm64/kvm/id_regs.c
+++ b/arch/arm64/kvm/id_regs.c
@@ -21,9 +21,12 @@
static u8 vcpu_pmuver(const struct kvm_vcpu *vcpu)
{
if (kvm_vcpu_has_pmu(vcpu))
- return vcpu->kvm->arch.dfr0_pmuver.imp;
+ return FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer),
+ IDREG(vcpu->kvm, SYS_ID_AA64DFR0_EL1));
+ else if (test_bit(KVM_ARCH_FLAG_VCPU_HAS_IMP_DEF_PMU, &vcpu->kvm->arch.flags))
+ return ID_AA64DFR0_EL1_PMUVer_IMP_DEF;
- return vcpu->kvm->arch.dfr0_pmuver.unimp;
+ return 0;
}
static u8 perfmon_to_pmuver(u8 perfmon)
@@ -256,10 +259,20 @@ static int set_id_aa64dfr0_el1(struct kvm_vcpu *vcpu,
if (val)
return -EINVAL;
- if (valid_pmu)
- vcpu->kvm->arch.dfr0_pmuver.imp = pmuver;
- else
- vcpu->kvm->arch.dfr0_pmuver.unimp = pmuver;
+ if (valid_pmu) {
+ mutex_lock(&vcpu->kvm->arch.config_lock);
+ IDREG(vcpu->kvm, SYS_ID_AA64DFR0_EL1) &= ~ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer);
+ IDREG(vcpu->kvm, SYS_ID_AA64DFR0_EL1) |=
+ FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer), pmuver);
+
+ IDREG(vcpu->kvm, SYS_ID_DFR0_EL1) &= ~ARM64_FEATURE_MASK(ID_DFR0_EL1_PerfMon);
+ IDREG(vcpu->kvm, SYS_ID_DFR0_EL1) |=
+ FIELD_PREP(ARM64_FEATURE_MASK(ID_DFR0_EL1_PerfMon), pmuver_to_perfmon(pmuver));
+ mutex_unlock(&vcpu->kvm->arch.config_lock);
+ } else {
+ assign_bit(KVM_ARCH_FLAG_VCPU_HAS_IMP_DEF_PMU, &vcpu->kvm->arch.flags,
+ pmuver == ID_AA64DFR0_EL1_PMUVer_IMP_DEF);
+ }
return 0;
}
@@ -296,10 +309,20 @@ static int set_id_dfr0_el1(struct kvm_vcpu *vcpu,
if (val)
return -EINVAL;
- if (valid_pmu)
- vcpu->kvm->arch.dfr0_pmuver.imp = perfmon_to_pmuver(perfmon);
- else
- vcpu->kvm->arch.dfr0_pmuver.unimp = perfmon_to_pmuver(perfmon);
+ if (valid_pmu) {
+ mutex_lock(&vcpu->kvm->arch.config_lock);
+ IDREG(vcpu->kvm, SYS_ID_DFR0_EL1) &= ~ARM64_FEATURE_MASK(ID_DFR0_EL1_PerfMon);
+ IDREG(vcpu->kvm, SYS_ID_DFR0_EL1) |=
+ FIELD_PREP(ARM64_FEATURE_MASK(ID_DFR0_EL1_PerfMon), perfmon);
+
+ IDREG(vcpu->kvm, SYS_ID_AA64DFR0_EL1) &= ~ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer);
+ IDREG(vcpu->kvm, SYS_ID_AA64DFR0_EL1) |=
+ FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer), perfmon_to_pmuver(perfmon));
+ mutex_unlock(&vcpu->kvm->arch.config_lock);
+ } else {
+ assign_bit(KVM_ARCH_FLAG_VCPU_HAS_IMP_DEF_PMU, &vcpu->kvm->arch.flags,
+ perfmon == ID_DFR0_EL1_PerfMon_IMPDEF);
+ }
return 0;
}
@@ -539,4 +562,12 @@ void kvm_arm_init_id_regs(struct kvm *kvm)
}
IDREG(kvm, SYS_ID_AA64PFR0_EL1) = val;
+
+ /*
+ * Initialise the default PMUver before there is a chance to
+ * create an actual PMU.
+ */
+ IDREG(kvm, SYS_ID_AA64DFR0_EL1) &= ~ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer);
+ IDREG(kvm, SYS_ID_AA64DFR0_EL1) |=
+ FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer), kvm_arm_pmu_get_pmuver_limit());
}
diff --git a/include/kvm/arm_pmu.h b/include/kvm/arm_pmu.h
index 628775334d5e..856ac59b6821 100644
--- a/include/kvm/arm_pmu.h
+++ b/include/kvm/arm_pmu.h
@@ -92,8 +92,9 @@ void kvm_vcpu_pmu_restore_host(struct kvm_vcpu *vcpu);
/*
* Evaluates as true when emulating PMUv3p5, and false otherwise.
*/
-#define kvm_pmu_is_3p5(vcpu) \
- (vcpu->kvm->arch.dfr0_pmuver.imp >= ID_AA64DFR0_EL1_PMUVer_V3P5)
+#define kvm_pmu_is_3p5(vcpu) \
+ (FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer), \
+ IDREG(vcpu->kvm, SYS_ID_AA64DFR0_EL1)) >= ID_AA64DFR0_EL1_PMUVer_V3P5)
u8 kvm_arm_pmu_get_pmuver_limit(void);
--
2.40.0.348.gf938b09366-goog
