public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Sean Christopherson <seanjc@google.com>
To: Sean Christopherson <seanjc@google.com>,
	Paolo Bonzini <pbonzini@redhat.com>,
	Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
	Maxim Levitsky <mlevitsk@redhat.com>
Subject: [PATCH v2 03/21] KVM: nSVM: Use the "outer" helper for writing multiplier to MSR_AMD64_TSC_RATIO
Date: Fri, 28 Jul 2023 18:15:50 -0700	[thread overview]
Message-ID: <20230729011608.1065019-4-seanjc@google.com> (raw)
In-Reply-To: <20230729011608.1065019-1-seanjc@google.com>

When emulating nested SVM transitions, use the outer helper for writing
the TSC multiplier for L2.  Using the inner helper only for one-off cases,
i.e. for paths where KVM is NOT emulating or modifying vCPU state, will
allow for multiple cleanups:

 - Explicitly disabling preemption only in the outer helper
 - Getting the multiplier from the vCPU field in the outer helper
 - Skipping the WRMSR in the outer helper if guest state isn't loaded

Opportunistically delete an extra newline.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/kvm/svm/nested.c | 4 ++--
 arch/x86/kvm/svm/svm.c    | 5 ++---
 arch/x86/kvm/svm/svm.h    | 2 +-
 3 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index c66c823ae222..5d5a1d7832fb 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -1103,7 +1103,7 @@ int nested_svm_vmexit(struct vcpu_svm *svm)
 	if (kvm_caps.has_tsc_control &&
 	    vcpu->arch.tsc_scaling_ratio != vcpu->arch.l1_tsc_scaling_ratio) {
 		vcpu->arch.tsc_scaling_ratio = vcpu->arch.l1_tsc_scaling_ratio;
-		__svm_write_tsc_multiplier(vcpu->arch.tsc_scaling_ratio);
+		svm_write_tsc_multiplier(vcpu, vcpu->arch.tsc_scaling_ratio);
 	}
 
 	svm->nested.ctl.nested_cr3 = 0;
@@ -1536,7 +1536,7 @@ void nested_svm_update_tsc_ratio_msr(struct kvm_vcpu *vcpu)
 	vcpu->arch.tsc_scaling_ratio =
 		kvm_calc_nested_tsc_multiplier(vcpu->arch.l1_tsc_scaling_ratio,
 					       svm->tsc_ratio_msr);
-	__svm_write_tsc_multiplier(vcpu->arch.tsc_scaling_ratio);
+	svm_write_tsc_multiplier(vcpu, vcpu->arch.tsc_scaling_ratio);
 }
 
 /* Inverse operation of nested_copy_vmcb_control_to_cache(). asid is copied too. */
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index d381ad424554..13f316375b14 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -550,7 +550,7 @@ static int svm_check_processor_compat(void)
 	return 0;
 }
 
-void __svm_write_tsc_multiplier(u64 multiplier)
+static void __svm_write_tsc_multiplier(u64 multiplier)
 {
 	preempt_disable();
 
@@ -1110,12 +1110,11 @@ static void svm_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
 	vmcb_mark_dirty(svm->vmcb, VMCB_INTERCEPTS);
 }
 
-static void svm_write_tsc_multiplier(struct kvm_vcpu *vcpu, u64 multiplier)
+void svm_write_tsc_multiplier(struct kvm_vcpu *vcpu, u64 multiplier)
 {
 	__svm_write_tsc_multiplier(multiplier);
 }
 
-
 /* Evaluate instruction intercepts that depend on guest CPUID features. */
 static void svm_recalc_instruction_intercepts(struct kvm_vcpu *vcpu,
 					      struct vcpu_svm *svm)
diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
index 18af7e712a5a..7132c0a04817 100644
--- a/arch/x86/kvm/svm/svm.h
+++ b/arch/x86/kvm/svm/svm.h
@@ -658,7 +658,7 @@ int nested_svm_check_exception(struct vcpu_svm *svm, unsigned nr,
 			       bool has_error_code, u32 error_code);
 int nested_svm_exit_special(struct vcpu_svm *svm);
 void nested_svm_update_tsc_ratio_msr(struct kvm_vcpu *vcpu);
-void __svm_write_tsc_multiplier(u64 multiplier);
+void svm_write_tsc_multiplier(struct kvm_vcpu *vcpu, u64 multiplier);
 void nested_copy_vmcb_control_to_cache(struct vcpu_svm *svm,
 				       struct vmcb_control_area *control);
 void nested_copy_vmcb_save_to_cache(struct vcpu_svm *svm,
-- 
2.41.0.487.g6d72f3e995-goog


  parent reply	other threads:[~2023-07-29  1:16 UTC|newest]

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-07-29  1:15 [PATCH v2 00/21] KVM: x86: Add "governed" X86_FEATURE framework Sean Christopherson
2023-07-29  1:15 ` [PATCH v2 01/21] KVM: nSVM: Check instead of asserting on nested TSC scaling support Sean Christopherson
2023-07-29  1:15 ` [PATCH v2 02/21] KVM: nSVM: Load L1's TSC multiplier based on L1 state, not L2 state Sean Christopherson
2023-07-29  1:15 ` Sean Christopherson [this message]
2023-07-29  1:15 ` [PATCH v2 04/21] KVM: SVM: Clean up preemption toggling related to MSR_AMD64_TSC_RATIO Sean Christopherson
2023-07-29  1:15 ` [PATCH v2 05/21] KVM: x86: Always write vCPU's current TSC offset/ratio in vendor hooks Sean Christopherson
2023-07-29  1:15 ` [PATCH v2 06/21] KVM: nSVM: Skip writes to MSR_AMD64_TSC_RATIO if guest state isn't loaded Sean Christopherson
2023-07-29  1:15 ` [PATCH v2 07/21] KVM: x86: Add a framework for enabling KVM-governed x86 features Sean Christopherson
2023-08-14  4:43   ` Zeng Guang
2023-08-14 17:20     ` Sean Christopherson
2023-07-29  1:15 ` [PATCH v2 08/21] KVM: x86/mmu: Use KVM-governed feature framework to track "GBPAGES enabled" Sean Christopherson
2023-07-29  1:15 ` [PATCH v2 09/21] KVM: VMX: Recompute "XSAVES enabled" only after CPUID update Sean Christopherson
2023-07-29  1:15 ` [PATCH v2 10/21] KVM: VMX: Check KVM CPU caps, not just VMX MSR support, for XSAVE enabling Sean Christopherson
2023-07-29  1:15 ` [PATCH v2 11/21] KVM: VMX: Rename XSAVES control to follow KVM's preferred "ENABLE_XYZ" Sean Christopherson
2023-07-29  1:15 ` [PATCH v2 12/21] KVM: x86: Use KVM-governed feature framework to track "XSAVES enabled" Sean Christopherson
2023-08-14  6:28   ` Zeng Guang
2023-07-29  1:16 ` [PATCH v2 13/21] KVM: nVMX: Use KVM-governed feature framework to track "nested VMX enabled" Sean Christopherson
2023-08-14  8:11   ` Yuan Yao
2023-07-29  1:16 ` [PATCH v2 14/21] KVM: nSVM: Use KVM-governed feature framework to track "NRIPS enabled" Sean Christopherson
2023-07-29  1:16 ` [PATCH v2 15/21] KVM: nSVM: Use KVM-governed feature framework to track "TSC scaling enabled" Sean Christopherson
2023-07-29  1:16 ` [PATCH v2 16/21] KVM: nSVM: Use KVM-governed feature framework to track "vVM{SAVE,LOAD} enabled" Sean Christopherson
2023-07-29  1:16 ` [PATCH v2 17/21] KVM: nSVM: Use KVM-governed feature framework to track "LBRv enabled" Sean Christopherson
2023-07-29  1:16 ` [PATCH v2 18/21] KVM: nSVM: Use KVM-governed feature framework to track "Pause Filter enabled" Sean Christopherson
2023-07-29  1:16 ` [PATCH v2 19/21] KVM: nSVM: Use KVM-governed feature framework to track "vGIF enabled" Sean Christopherson
2023-07-29  1:16 ` [PATCH v2 20/21] KVM: nSVM: Use KVM-governed feature framework to track "vNMI enabled" Sean Christopherson
2023-07-29  1:16 ` [PATCH v2 21/21] KVM: x86: Disallow guest CPUID lookups when IRQs are disabled Sean Christopherson
2023-08-04  0:40 ` [PATCH v2 00/21] KVM: x86: Add "governed" X86_FEATURE framework Sean Christopherson

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=20230729011608.1065019-4-seanjc@google.com \
    --to=seanjc@google.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mlevitsk@redhat.com \
    --cc=pbonzini@redhat.com \
    --cc=vkuznets@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