[PATCH V7 10/18] KVM: x86/pmu: Adjust precise_ip to emulate Ice Lake guest PDIR counter
From: Zhu Lingshan <hidden>
Date: 2021-06-22 09:44:35
Also in:
lkml
Subsystem:
kernel virtual machine for x86 (kvm/x86), the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Sean Christopherson, Paolo Bonzini, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
From: Like Xu <redacted> The PEBS-PDIR facility on Ice Lake server is supported on IA31_FIXED0 only. If the guest configures counter 32 and PEBS is enabled, the PEBS-PDIR facility is supposed to be used, in which case KVM adjusts attr.precise_ip to 3 and request host perf to assign the exactly requested counter or fail. The CPU model check is also required since some platforms may place the PEBS-PDIR facility in another counter index. Signed-off-by: Like Xu <redacted> Signed-off-by: Zhu Lingshan <redacted> --- arch/x86/kvm/pmu.c | 2 ++ arch/x86/kvm/pmu.h | 7 +++++++ 2 files changed, 9 insertions(+)
diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
index d76b0a5d80d7..b907aba35ff3 100644
--- a/arch/x86/kvm/pmu.c
+++ b/arch/x86/kvm/pmu.c@@ -153,6 +153,8 @@ static void pmc_reprogram_counter(struct kvm_pmc *pmc, u32 type, * could possibly care here is unsupported and needs changes. */ attr.precise_ip = 1; + if (x86_match_cpu(vmx_icl_pebs_cpu) && pmc->idx == 32) + attr.precise_ip = 3; } if (pebs || intr) ovf = kvm_perf_overflow_intr;
diff --git a/arch/x86/kvm/pmu.h b/arch/x86/kvm/pmu.h
index 67e753edfa22..1af86ae1d3f2 100644
--- a/arch/x86/kvm/pmu.h
+++ b/arch/x86/kvm/pmu.h@@ -4,6 +4,8 @@ #include <linux/nospec.h> +#include <asm/cpu_device_id.h> + #define vcpu_to_pmu(vcpu) (&(vcpu)->arch.pmu) #define pmu_to_vcpu(pmu) (container_of((pmu), struct kvm_vcpu, arch.pmu)) #define pmc_to_pmu(pmc) (&(pmc)->vcpu->arch.pmu)
@@ -16,6 +18,11 @@ #define VMWARE_BACKDOOR_PMC_APPARENT_TIME 0x10002 #define MAX_FIXED_COUNTERS 3 +static const struct x86_cpu_id vmx_icl_pebs_cpu[] = { + X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_D, NULL), + X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_X, NULL), + {} +}; struct kvm_event_hw_type_mapping { u8 eventsel;
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2.27.0