Skip masking STALL_SLOT, STALL_SLOT_FRONTEND and STALL_SLOT_BACKEND out
of PMCEID1 when KVM_ARM_VCPU_PMU_V3_STRICT is set, because this is when
PMMIR_EL1.SLOTS is exposed to guests, making these events meaningful for
collection.

Change the parameter of compute_pmceid1() from arm_pmu to kvm_vcpu, to
check if KVM_ARM_VCPU_PMU_V3_STRICT is set. Also updated the signature of
compute_pmceid0() for consistency.

Signed-off-by: Congkai Tan <[email protected]>
Reviewed-by: Geoff Blake <[email protected]>
Reviewed-by: Haris Okanovic <[email protected]>
Reviewed-by: Stanislav Spassov <[email protected]>
---
 arch/arm64/kvm/pmu-emul.c | 25 +++++++++++++------------
 1 file changed, 13 insertions(+), 12 deletions(-)

diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c
index 9595bce6519f..89eec5a1a499 100644
--- a/arch/arm64/kvm/pmu-emul.c
+++ b/arch/arm64/kvm/pmu-emul.c
@@ -851,9 +851,9 @@ static u64 __compute_pmceid(struct arm_pmu *pmu, bool 
pmceid1)
        return ((u64)hi[pmceid1] << 32) | lo[pmceid1];
 }
 
-static u64 compute_pmceid0(struct arm_pmu *pmu)
+static u64 compute_pmceid0(struct kvm_vcpu *vcpu)
 {
-       u64 val = __compute_pmceid(pmu, 0);
+       u64 val = __compute_pmceid(vcpu->kvm->arch.arm_pmu, 0);
 
        /* always support SW_INCR */
        val |= BIT(ARMV8_PMUV3_PERFCTR_SW_INCR);
@@ -862,32 +862,33 @@ static u64 compute_pmceid0(struct arm_pmu *pmu)
        return val;
 }
 
-static u64 compute_pmceid1(struct arm_pmu *pmu)
+static u64 compute_pmceid1(struct kvm_vcpu *vcpu)
 {
-       u64 val = __compute_pmceid(pmu, 1);
+       u64 val = __compute_pmceid(vcpu->kvm->arch.arm_pmu, 1);
 
        /*
-        * Don't advertise STALL_SLOT*, as PMMIR_EL0 is handled
-        * as RAZ
+        * If KVM_ARM_VCPU_PMU_V3_STRICT is not set, PMMIR_EL1 is
+        * unconditionally RAZ, so don't advertise STALL_SLOT* events.
         */
-       val &= ~(BIT_ULL(ARMV8_PMUV3_PERFCTR_STALL_SLOT - 32) |
-                BIT_ULL(ARMV8_PMUV3_PERFCTR_STALL_SLOT_FRONTEND - 32) |
-                BIT_ULL(ARMV8_PMUV3_PERFCTR_STALL_SLOT_BACKEND - 32));
+       if (!kvm_vcpu_has_pmuv3_strict(vcpu))
+               val &= ~(BIT_ULL(ARMV8_PMUV3_PERFCTR_STALL_SLOT - 32) |
+                        BIT_ULL(ARMV8_PMUV3_PERFCTR_STALL_SLOT_FRONTEND - 32) |
+                        BIT_ULL(ARMV8_PMUV3_PERFCTR_STALL_SLOT_BACKEND - 32));
+
        return val;
 }
 
 u64 kvm_pmu_get_pmceid(struct kvm_vcpu *vcpu, bool pmceid1)
 {
-       struct arm_pmu *cpu_pmu = vcpu->kvm->arch.arm_pmu;
        unsigned long *bmap = vcpu->kvm->arch.pmu_filter;
        u64 val, mask = 0;
        int base, i, nr_events;
 
        if (!pmceid1) {
-               val = compute_pmceid0(cpu_pmu);
+               val = compute_pmceid0(vcpu);
                base = 0;
        } else {
-               val = compute_pmceid1(cpu_pmu);
+               val = compute_pmceid1(vcpu);
                base = 32;
        }
 
-- 
2.50.1


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