At the moment a SW_INCR counter always overflows on 32-bit
boundary, independently on whether the n+1th counter is
programmed as CHAIN.
Check whether the SW_INCR counter is a 64b counter and if so,
implement the 64b logic.
Fixes: 80f393a23be6 ("KVM: arm/arm64: Support chained PMU counters")
Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx>
---
virt/kvm/arm/pmu.c | 16 +++++++++++++++-
1 file changed, 15 insertions(+), 1 deletion(-)
diff --git a/virt/kvm/arm/pmu.c b/virt/kvm/arm/pmu.c
index c3f8b059881e..7ab477db2f75 100644
--- a/virt/kvm/arm/pmu.c
+++ b/virt/kvm/arm/pmu.c
@@ -491,6 +491,8 @@ void kvm_pmu_software_increment(struct kvm_vcpu *vcpu, u64 val)
enable = __vcpu_sys_reg(vcpu, PMCNTENSET_EL0);
for (i = 0; i < ARMV8_PMU_CYCLE_IDX; i++) {
+ bool chained = test_bit(i >> 1, vcpu->arch.pmu.chained);
+
if (!(val & BIT(i)))
continue;
type = __vcpu_sys_reg(vcpu, PMEVTYPER0_EL0 + i)
@@ -500,8 +502,20 @@ void kvm_pmu_software_increment(struct kvm_vcpu *vcpu, u64 val)
reg = __vcpu_sys_reg(vcpu, PMEVCNTR0_EL0 + i) + 1;
reg = lower_32_bits(reg);
__vcpu_sys_reg(vcpu, PMEVCNTR0_EL0 + i) = reg;
- if (!reg)
+ if (reg) /* no overflow */
+ continue;
+ if (chained) {
+ reg = __vcpu_sys_reg(vcpu, PMEVCNTR0_EL0 + i + 1) + 1;
+ reg = lower_32_bits(reg);
+ __vcpu_sys_reg(vcpu, PMEVCNTR0_EL0 + i + 1) = reg;
+ if (reg)
+ continue;
+ /* mark an overflow on high counter */
+ __vcpu_sys_reg(vcpu, PMOVSSET_EL0) |= BIT(i + 1);
+ } else {
+ /* mark an overflow */
__vcpu_sys_reg(vcpu, PMOVSSET_EL0) |= BIT(i);
+ }
}
}
}
--
2.20.1
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