diff options
| author | Eric Auger <eric.auger@redhat.com> | 2020-01-24 15:25:34 +0100 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2020-01-28 12:50:33 +0000 |
| commit | aa76829171e98bd75a0cc00b6248eca269ac7f4f (patch) | |
| tree | af7c8ea2704a2ba2d3007818fc064a019476545b | |
| parent | 76c9fc56ddfdfeb0c9ff984d0d63b083e608fc92 (diff) | |
| download | linux-aa76829171e98bd75a0cc00b6248eca269ac7f4f.tar.bz2 | |
KVM: arm64: pmu: Fix chained SW_INCR counters
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@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200124142535.29386-4-eric.auger@redhat.com
| -rw-r--r-- | virt/kvm/arm/pmu.c | 43 |
1 files changed, 30 insertions, 13 deletions
diff --git a/virt/kvm/arm/pmu.c b/virt/kvm/arm/pmu.c index 9f605e0b8dd7..560db6282137 100644 --- a/virt/kvm/arm/pmu.c +++ b/virt/kvm/arm/pmu.c @@ -477,28 +477,45 @@ static void kvm_pmu_perf_overflow(struct perf_event *perf_event, */ void kvm_pmu_software_increment(struct kvm_vcpu *vcpu, u64 val) { + struct kvm_pmu *pmu = &vcpu->arch.pmu; int i; - u64 type, enable, reg; - - if (val == 0) - return; if (!(__vcpu_sys_reg(vcpu, PMCR_EL0) & ARMV8_PMU_PMCR_E)) return; - enable = __vcpu_sys_reg(vcpu, PMCNTENSET_EL0); + /* Weed out disabled counters */ + val &= __vcpu_sys_reg(vcpu, PMCNTENSET_EL0); + for (i = 0; i < ARMV8_PMU_CYCLE_IDX; i++) { + u64 type, reg; + if (!(val & BIT(i))) continue; - type = __vcpu_sys_reg(vcpu, PMEVTYPER0_EL0 + i) - & ARMV8_PMU_EVTYPE_EVENT; - if ((type == ARMV8_PMUV3_PERFCTR_SW_INCR) - && (enable & BIT(i))) { - reg = __vcpu_sys_reg(vcpu, PMEVCNTR0_EL0 + i) + 1; + + /* PMSWINC only applies to ... SW_INC! */ + type = __vcpu_sys_reg(vcpu, PMEVTYPER0_EL0 + i); + type &= ARMV8_PMU_EVTYPE_EVENT; + if (type != ARMV8_PMUV3_PERFCTR_SW_INCR) + continue; + + /* increment this even SW_INC counter */ + reg = __vcpu_sys_reg(vcpu, PMEVCNTR0_EL0 + i) + 1; + reg = lower_32_bits(reg); + __vcpu_sys_reg(vcpu, PMEVCNTR0_EL0 + i) = reg; + + if (reg) /* no overflow on the low part */ + continue; + + if (kvm_pmu_pmc_is_chained(&pmu->pmc[i])) { + /* increment the high counter */ + reg = __vcpu_sys_reg(vcpu, PMEVCNTR0_EL0 + i + 1) + 1; reg = lower_32_bits(reg); - __vcpu_sys_reg(vcpu, PMEVCNTR0_EL0 + i) = reg; - if (!reg) - __vcpu_sys_reg(vcpu, PMOVSSET_EL0) |= BIT(i); + __vcpu_sys_reg(vcpu, PMEVCNTR0_EL0 + i + 1) = reg; + if (!reg) /* mark overflow on the high counter */ + __vcpu_sys_reg(vcpu, PMOVSSET_EL0) |= BIT(i + 1); + } else { + /* mark overflow on low counter */ + __vcpu_sys_reg(vcpu, PMOVSSET_EL0) |= BIT(i); } } } |