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authorPaolo Bonzini <pbonzini@redhat.com>2013-03-28 17:18:35 +0100
committerGleb Natapov <gleb@redhat.com>2013-04-02 17:42:44 +0300
commitafd80d85aefac27e6e2f9dc10f60515357c504d2 (patch)
treef9c59ac17a12e113d9eff004e3bdae40ea995f35 /arch/x86/kvm/pmu.c
parente1e2e605c2ad6791ce6346b22443ce611709fa65 (diff)
downloadlinux-stericsson-afd80d85aefac27e6e2f9dc10f60515357c504d2.tar.gz
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.c14
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))) {