linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Wei Wang <wei.w.wang@intel.com>
To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
	pbonzini@redhat.com, ak@linux.intel.com
Cc: kan.liang@intel.com, peterz@infradead.org, mingo@redhat.com,
	rkrcmar@redhat.com, like.xu@intel.com, wei.w.wang@intel.com
Subject: [PATCH v2 4/8] KVM/x86: expose MSR_IA32_PERF_CAPABILITIES to the guest
Date: Thu,  6 Sep 2018 19:30:52 +0800	[thread overview]
Message-ID: <1536233456-12173-5-git-send-email-wei.w.wang@intel.com> (raw)
In-Reply-To: <1536233456-12173-1-git-send-email-wei.w.wang@intel.com>

Bits [0, 5] of MSR_IA32_PERF_CAPABILITIES tell about the format of
the addresses stored in the LBR stack. Expose those bits to the guest
when the guest lbr feature is enabled.

Signed-off-by: Like Xu <like.xu@intel.com>
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
---
 arch/x86/include/asm/perf_event.h | 2 ++
 arch/x86/kvm/cpuid.c              | 2 +-
 arch/x86/kvm/vmx.c                | 7 +++++++
 3 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h
index f40e80a..161165f 100644
--- a/arch/x86/include/asm/perf_event.h
+++ b/arch/x86/include/asm/perf_event.h
@@ -79,6 +79,8 @@
 #define ARCH_PERFMON_BRANCH_MISSES_RETIRED		6
 #define ARCH_PERFMON_EVENTS_COUNT			7
 
+#define PERF_CAP_MASK_LBR_FMT				0x3f
+
 /*
  * Intel "Architectural Performance Monitoring" CPUID
  * detection/enumeration details:
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 7bcfa61..3b8a57b 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -365,7 +365,7 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
 		F(XMM3) | F(PCLMULQDQ) | 0 /* DTES64, MONITOR */ |
 		0 /* DS-CPL, VMX, SMX, EST */ |
 		0 /* TM2 */ | F(SSSE3) | 0 /* CNXT-ID */ | 0 /* Reserved */ |
-		F(FMA) | F(CX16) | 0 /* xTPR Update, PDCM */ |
+		F(FMA) | F(CX16) | 0 /* xTPR Update*/ | F(PDCM) |
 		F(PCID) | 0 /* Reserved, DCA */ | F(XMM4_1) |
 		F(XMM4_2) | F(X2APIC) | F(MOVBE) | F(POPCNT) |
 		0 /* Reserved*/ | F(AES) | F(XSAVE) | 0 /* OSXSAVE */ | F(AVX) |
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 7a62c1c..d5eba8e 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -4134,6 +4134,13 @@ static int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
 		    !guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP))
 			return 1;
 		/* Otherwise falls through */
+	case MSR_IA32_PERF_CAPABILITIES:
+		if (!boot_cpu_has(X86_FEATURE_PDCM))
+			return 1;
+		msr_info->data = native_read_msr(MSR_IA32_PERF_CAPABILITIES);
+		if (vcpu->kvm->arch.guest_lbr)
+			msr_info->data &= PERF_CAP_MASK_LBR_FMT;
+		break;
 	default:
 		msr = find_msr_entry(vmx, msr_info->index);
 		if (msr) {
-- 
2.7.4


  parent reply	other threads:[~2018-09-06 12:01 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-09-06 11:30 [PATCH v2 0/8] Guest LBR Enabling Wei Wang
2018-09-06 11:30 ` [PATCH v2 1/8] perf/x86: add a function to get the lbr stack Wei Wang
2018-09-07  3:28   ` Andi Kleen
2018-09-07  6:45     ` Wei Wang
2018-09-06 11:30 ` [PATCH v2 2/8] KVM/x86: KVM_CAP_X86_GUEST_LBR Wei Wang
2018-09-06 11:30 ` [PATCH v2 3/8] KVM/vmx: Pass through the lbr stack to a guest Wei Wang
2018-09-06 11:30 ` Wei Wang [this message]
2018-09-06 11:30 ` [PATCH v2 5/8] KVM/x86: enable the guest to access the debugctl msr Wei Wang
2018-09-06 11:30 ` [PATCH v2 6/8] perf/x86/intel/lbr: guest requesting KVM for lbr stack save/restore Wei Wang
2018-09-07  3:27   ` Andi Kleen
2018-09-07  5:24     ` Wei Wang
2018-09-07 14:10       ` Andi Kleen
2018-09-07 15:20         ` Wang, Wei W
2018-09-07 20:05           ` Andi Kleen
2018-09-08  1:34             ` Wang, Wei W
2018-09-06 11:30 ` [PATCH v2 7/8] KVM: PMU: support to save/restore the guest lbr stack on vCPU switching Wei Wang
2018-09-07 14:36   ` Jann Horn
2018-09-07 15:21     ` Wang, Wei W
2018-09-18  0:58   ` Gonglei (Arei)
2018-09-18  2:56     ` Andi Kleen
2018-09-18  9:57       ` Wei Wang
2018-09-18 10:34         ` Gonglei (Arei)
2018-09-06 11:30 ` [PATCH v2 8/8] perf/x86/intel/lbr: add the guest_lbr boolean to cpuc Wei Wang

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1536233456-12173-5-git-send-email-wei.w.wang@intel.com \
    --to=wei.w.wang@intel.com \
    --cc=ak@linux.intel.com \
    --cc=kan.liang@intel.com \
    --cc=kvm@vger.kernel.org \
    --cc=like.xu@intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@redhat.com \
    --cc=pbonzini@redhat.com \
    --cc=peterz@infradead.org \
    --cc=rkrcmar@redhat.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).