From: Like Xu <like.xu@linux.intel.com>
To: Paolo Bonzini <pbonzini@redhat.com>,
Sean Christopherson <seanjc@google.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>,
Wanpeng Li <wanpengli@tencent.com>,
Jim Mattson <jmattson@google.com>, Joerg Roedel <joro@8bytes.org>,
ak@linux.intel.com, wei.w.wang@intel.com, kan.liang@intel.com,
alex.shi@linux.alibaba.com, kvm@vger.kernel.org, x86@kernel.org,
linux-kernel@vger.kernel.org
Subject: [PATCH v14 10/11] KVM: vmx/pmu: Expose LBR_FMT in the MSR_IA32_PERF_CAPABILITIES
Date: Mon, 1 Feb 2021 13:10:38 +0800 [thread overview]
Message-ID: <20210201051039.255478-11-like.xu@linux.intel.com> (raw)
In-Reply-To: <20210201051039.255478-1-like.xu@linux.intel.com>
Userspace could enable guest LBR feature when the exactly supported
LBR format value is initialized to the MSR_IA32_PERF_CAPABILITIES
and the LBR is also compatible with vPMU version and host cpu model.
The LBR could be enabled on the guest if host perf supports LBR
(checked via x86_perf_get_lbr()) and the vcpu model is compatible
with the host one.
Signed-off-by: Like Xu <like.xu@linux.intel.com>
---
arch/x86/kvm/vmx/capabilities.h | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/vmx/capabilities.h b/arch/x86/kvm/vmx/capabilities.h
index 57b940c613ab..c49f3ee8eca8 100644
--- a/arch/x86/kvm/vmx/capabilities.h
+++ b/arch/x86/kvm/vmx/capabilities.h
@@ -374,11 +374,18 @@ static inline bool vmx_pt_mode_is_host_guest(void)
static inline u64 vmx_get_perf_capabilities(void)
{
+ u64 perf_cap;
+
+ if (boot_cpu_has(X86_FEATURE_PDCM))
+ rdmsrl(MSR_IA32_PERF_CAPABILITIES, perf_cap);
+
+ perf_cap &= PMU_CAP_LBR_FMT;
+
/*
* Since counters are virtualized, KVM would support full
* width counting unconditionally, even if the host lacks it.
*/
- return PMU_CAP_FW_WRITES;
+ return PMU_CAP_FW_WRITES | perf_cap;
}
static inline u64 vmx_supported_debugctl(void)
--
2.29.2
next prev parent reply other threads:[~2021-02-01 6:43 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-01 5:10 [PATCH v14 00/11] KVM: x86/pmu: Guest Last Branch Recording Enabling Like Xu
2021-02-01 5:10 ` [PATCH v14 01/11] KVM: x86/vmx: Make vmx_set_intercept_for_msr() non-static Like Xu
2021-02-01 5:10 ` [PATCH v14 02/11] KVM: x86/pmu: Set up IA32_PERF_CAPABILITIES if PDCM bit is available Like Xu
2021-02-02 11:48 ` Paolo Bonzini
2021-02-01 5:10 ` [PATCH v14 03/11] KVM: vmx/pmu: Add PMU_CAP_LBR_FMT check when guest LBR is enabled Like Xu
2021-02-02 12:00 ` Paolo Bonzini
2021-02-01 5:10 ` [PATCH v14 04/11] KVM: vmx/pmu: Expose DEBUGCTLMSR_LBR in the MSR_IA32_DEBUGCTLMSR Like Xu
2021-02-01 5:10 ` [PATCH v14 05/11] KVM: vmx/pmu: Create a guest LBR event when vcpu sets DEBUGCTLMSR_LBR Like Xu
2021-02-01 5:10 ` [PATCH v14 06/11] KVM: vmx/pmu: Pass-through LBR msrs when the guest LBR event is ACTIVE Like Xu
2021-02-01 5:10 ` [PATCH v14 07/11] KVM: vmx/pmu: Reduce the overhead of LBR pass-through or cancellation Like Xu
2021-02-01 5:10 ` [PATCH v14 08/11] KVM: vmx/pmu: Emulate legacy freezing LBRs on virtual PMI Like Xu
2021-02-01 5:10 ` [PATCH v14 09/11] KVM: vmx/pmu: Release guest LBR event via lazy release mechanism Like Xu
2021-02-01 5:10 ` Like Xu [this message]
2021-02-01 5:10 ` [PATCH v14 11/11] selftests: kvm/x86: add test for pmu msr MSR_IA32_PERF_CAPABILITIES Like Xu
2021-02-01 6:01 ` [PATCH v14 07/11] KVM: vmx/pmu: Reduce the overhead of LBR pass-through or cancellation Like Xu
2021-02-01 6:01 ` [PATCH v14 08/11] KVM: vmx/pmu: Emulate legacy freezing LBRs on virtual PMI Like Xu
2021-02-01 6:01 ` [PATCH v14 09/11] KVM: vmx/pmu: Release guest LBR event via lazy release mechanism Like Xu
2021-02-01 6:01 ` [PATCH v14 10/11] KVM: vmx/pmu: Expose LBR_FMT in the MSR_IA32_PERF_CAPABILITIES Like Xu
2021-02-01 6:01 ` [PATCH v14 11/11] selftests: kvm/x86: add test for pmu msr MSR_IA32_PERF_CAPABILITIES Like Xu
2021-02-02 14:53 ` Paolo Bonzini
2021-02-02 12:37 ` [PATCH v14 00/11] KVM: x86/pmu: Guest Last Branch Recording Enabling Paolo Bonzini
2021-07-29 12:40 ` Liuxiangdong
2021-07-30 3:15 ` Liuxiangdong
2021-07-30 3:28 ` Like Xu
2022-09-13 23:42 ` Jim Mattson
2022-09-19 7:26 ` Like Xu
2022-09-19 18:08 ` Jim Mattson
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