Re: [PATCH v2 0/2] Inject a PMI for KVM Guest when ToPA buffer is filled

From: Paolo Bonzini
Date: Fri Feb 22 2019 - 12:25:23 EST


On 19/02/19 01:26, Luwei Kang wrote:
> Each intel processor trace table of physical addresses (ToPA) entry
> has an INT bit. If this bit is set, the processor will signal a
> performance-monitoring interrupt (PMI) when the corresponding trace
> output region is filled. This patch set will inject a PMI for Intel
> Processor Trace when ToPA buffer is filled.
>
>>From v1:
> - Exported a global function pointers may not a good chioce.
> Add a new member in kvm_guest_cbs to send Intel PT PMI for KVM guest.
>
> Luwei Kang (2):
> KVM: x86: Inject PMI for KVM guest
> KVM: x86: Add support of clear Trace_ToPA_PMI status
>
> arch/x86/events/intel/core.c | 6 +++++-
> arch/x86/include/asm/kvm_host.h | 1 +
> arch/x86/include/asm/msr-index.h | 8 ++++++++
> arch/x86/kvm/vmx/pmu_intel.c | 8 +++++++-
> arch/x86/kvm/x86.c | 10 ++++++++++
> include/linux/perf_event.h | 1 +
> 6 files changed, 32 insertions(+), 2 deletions(-)
>

Queued, with just a little change in patch 2:

diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c
index 6dee7cf24442..f8502c376b37 100644
--- a/arch/x86/kvm/vmx/pmu_intel.c
+++ b/arch/x86/kvm/vmx/pmu_intel.c
@@ -297,9 +297,9 @@ static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
pmu->global_ctrl = ((1ull << pmu->nr_arch_gp_counters) - 1) |
(((1ull << pmu->nr_arch_fixed_counters) - 1) << INTEL_PMC_IDX_FIXED);
pmu->global_ctrl_mask = ~pmu->global_ctrl;
- pmu->global_ovf_ctrl_mask = ~(pmu->global_ctrl |
- MSR_CORE_PERF_GLOBAL_OVF_CTRL_OVF_BUF |
- MSR_CORE_PERF_GLOBAL_OVF_CTRL_COND_CHGD);
+ pmu->global_ovf_ctrl_mask = pmu->global_ctrl_mask
+ & ~(MSR_CORE_PERF_GLOBAL_OVF_CTRL_OVF_BUF |
+ MSR_CORE_PERF_GLOBAL_OVF_CTRL_COND_CHGD);
if (kvm_x86_ops->pt_supported())
pmu->global_ovf_ctrl_mask &=
~MSR_CORE_PERF_GLOBAL_OVF_CTRL_TRACE_TOPA_PMI;

this makes the review easier, and also makes the assignment look
the same as the one inside the "if (kvm_x86_ops->pt_supported())".

Paolo