diff options
| author | Paolo Bonzini <pbonzini@redhat.com> | 2013-03-28 17:18:35 +0100 |
|---|---|---|
| committer | Gleb Natapov <gleb@redhat.com> | 2013-04-02 16:42:44 +0200 |
| commit | afd80d85aefac27e6e2f9dc10f60515357c504d2 (patch) | |
| tree | f9c59ac17a12e113d9eff004e3bdae40ea995f35 /arch/x86/kvm/pmu.c | |
| parent | KVM: s390: Enable KVM_CAP_NR_MEMSLOTS on s390 (diff) | |
| download | linux-afd80d85aefac27e6e2f9dc10f60515357c504d2.tar.xz linux-afd80d85aefac27e6e2f9dc10f60515357c504d2.zip | |
pmu: prepare for migration support
In order to migrate the PMU state correctly, we need to restore the
values of MSR_CORE_PERF_GLOBAL_STATUS (a read-only register) and
MSR_CORE_PERF_GLOBAL_OVF_CTRL (which has side effects when written).
We also need to write the full 40-bit value of the performance counter,
which would only be possible with a v3 architectural PMU's full-width
counter MSRs.
To distinguish host-initiated writes from the guest's, pass the
full struct msr_data to kvm_pmu_set_msr.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Diffstat (limited to 'arch/x86/kvm/pmu.c')
| -rw-r--r-- | arch/x86/kvm/pmu.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c index cfc258a6bf97..c53e797e7369 100644 --- a/arch/x86/kvm/pmu.c +++ b/arch/x86/kvm/pmu.c @@ -360,10 +360,12 @@ int kvm_pmu_get_msr(struct kvm_vcpu *vcpu, u32 index, u64 *data) return 1; } -int kvm_pmu_set_msr(struct kvm_vcpu *vcpu, u32 index, u64 data) +int kvm_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) { struct kvm_pmu *pmu = &vcpu->arch.pmu; struct kvm_pmc *pmc; + u32 index = msr_info->index; + u64 data = msr_info->data; switch (index) { case MSR_CORE_PERF_FIXED_CTR_CTRL: @@ -375,6 +377,10 @@ int kvm_pmu_set_msr(struct kvm_vcpu *vcpu, u32 index, u64 data) } break; case MSR_CORE_PERF_GLOBAL_STATUS: + if (msr_info->host_initiated) { + pmu->global_status = data; + return 0; + } break; /* RO MSR */ case MSR_CORE_PERF_GLOBAL_CTRL: if (pmu->global_ctrl == data) @@ -386,7 +392,8 @@ int kvm_pmu_set_msr(struct kvm_vcpu *vcpu, u32 index, u64 data) break; case MSR_CORE_PERF_GLOBAL_OVF_CTRL: if (!(data & (pmu->global_ctrl_mask & ~(3ull<<62)))) { - pmu->global_status &= ~data; + if (!msr_info->host_initiated) + pmu->global_status &= ~data; pmu->global_ovf_ctrl = data; return 0; } @@ -394,7 +401,8 @@ int kvm_pmu_set_msr(struct kvm_vcpu *vcpu, u32 index, u64 data) default: if ((pmc = get_gp_pmc(pmu, index, MSR_IA32_PERFCTR0)) || (pmc = get_fixed_pmc(pmu, index))) { - data = (s64)(s32)data; + if (!msr_info->host_initiated) + data = (s64)(s32)data; pmc->counter += data - read_pmc(pmc); return 0; } else if ((pmc = get_gp_pmc(pmu, index, MSR_P6_EVNTSEL0))) { |