From: Paolo Bonzini <pbonzini@redhat.com>
To: Maxim Levitsky <mlevitsk@redhat.com>, kvm@vger.kernel.org
Cc: Wanpeng Li <wanpengli@tencent.com>,
Thomas Gleixner <tglx@linutronix.de>,
Joerg Roedel <joro@8bytes.org>, Borislav Petkov <bp@alien8.de>,
Sean Christopherson <seanjc@google.com>,
Jim Mattson <jmattson@google.com>,
"maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)"
<x86@kernel.org>,
"open list:X86 ARCHITECTURE (32-BIT AND 64-BIT)"
<linux-kernel@vger.kernel.org>,
Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>,
Vitaly Kuznetsov <vkuznets@redhat.com>,
Ingo Molnar <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [PATCH v3 11/12] KVM: SVM: call avic_vcpu_load/avic_vcpu_put when enabling/disabling AVIC
Date: Tue, 3 Aug 2021 11:00:10 +0200 [thread overview]
Message-ID: <5a3b940b-7290-ca37-b3a4-bf01b7c4a6bb@redhat.com> (raw)
In-Reply-To: <20210802183329.2309921-12-mlevitsk@redhat.com>
On 02/08/21 20:33, Maxim Levitsky wrote:
> @@ -651,6 +673,7 @@ void svm_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu)
> }
> vmcb_mark_dirty(vmcb, VMCB_AVIC);
>
> + __avic_set_running(vcpu, activated);
> svm_set_pi_irte_mode(vcpu, activated);
> }
>
I'd rather have calls to avic_vcpu_load/avic_vcpu_put directly inside
the "if (activated)", and leaving avic_set_running to its current
implementation. That way you don't need __avic_set_running (which is a
confusing name, because it does more than just setting the running bit).
> void kvm_vcpu_update_apicv(struct kvm_vcpu *vcpu)
> {
> + bool activate;
> +
> if (!lapic_in_kernel(vcpu))
> return;
>
> mutex_lock(&vcpu->kvm->arch.apicv_update_lock);
>
> - vcpu->arch.apicv_active = kvm_apicv_activated(vcpu->kvm);
> + activate = kvm_apicv_activated(vcpu->kvm);
> + if (vcpu->arch.apicv_active == activate)
> + goto out;
> +
> + vcpu->arch.apicv_active = activate;
> kvm_apic_update_apicv(vcpu);
> static_call(kvm_x86_refresh_apicv_exec_ctrl)(vcpu);
>
> @@ -9257,6 +9263,7 @@ void kvm_vcpu_update_apicv(struct kvm_vcpu *vcpu)
> if (!vcpu->arch.apicv_active)
> kvm_make_request(KVM_REQ_EVENT, vcpu);
>
> +out:
> mutex_unlock(&vcpu->kvm->arch.apicv_update_lock);
> }
> EXPORT_SYMBOL_GPL(kvm_vcpu_update_apicv);
Should this be a separate patch?
As an aside, we have
static inline bool kvm_vcpu_apicv_active(struct kvm_vcpu *vcpu)
{
return vcpu->arch.apic && vcpu->arch.apicv_active;
}
but really vcpu->arch.apicv_active should never be true if
vcpu->arch.apic is. So it should be possible to change this to "return
vcpu->arch.apicv_active" with a comment that the serialization between
apicv_inhibit_reasons and apicv_active happens via apicv_update_lock.
Thanks,
Paolo
next prev parent reply other threads:[~2021-08-03 9:00 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-08-02 18:33 [PATCH v3 00/12] My AVIC patch queue Maxim Levitsky
2021-08-02 18:33 ` [PATCH v3 01/12] Revert "KVM: x86/mmu: Allow zap gfn range to operate under the mmu read lock" Maxim Levitsky
2021-08-03 8:05 ` Paolo Bonzini
2021-08-03 15:11 ` Sean Christopherson
2021-08-03 17:29 ` Paolo Bonzini
2021-08-02 18:33 ` [PATCH v3 02/12] KVM: x86/mmu: bump mmu notifier count in kvm_zap_gfn_range Maxim Levitsky
2021-08-03 9:00 ` Paolo Bonzini
2021-08-02 18:33 ` [PATCH v3 03/12] KVM: x86/mmu: rename try_async_pf to kvm_faultin_pfn Maxim Levitsky
2021-08-03 9:00 ` Paolo Bonzini
2021-08-02 18:33 ` [PATCH v3 04/12] KVM: x86/mmu: allow kvm_faultin_pfn to return page fault handling code Maxim Levitsky
2021-08-03 9:00 ` Paolo Bonzini
2021-08-02 18:33 ` [PATCH v3 05/12] KVM: x86/mmu: allow APICv memslot to be partially enabled Maxim Levitsky
2021-08-03 9:12 ` Paolo Bonzini
2021-08-02 18:33 ` [PATCH v3 06/12] KVM: x86: don't disable APICv memslot when inhibited Maxim Levitsky
2021-08-03 8:44 ` Paolo Bonzini
2021-08-09 18:51 ` Maxim Levitsky
2021-08-09 19:14 ` Sean Christopherson
2021-08-02 18:33 ` [PATCH v3 07/12] KVM: x86: APICv: fix race in kvm_request_apicv_update on SVM Maxim Levitsky
2021-08-02 18:33 ` [PATCH v3 08/12] KVM: SVM: add warning for mistmatch between AVIC state and AVIC access page state Maxim Levitsky
2021-08-03 8:45 ` Paolo Bonzini
2021-08-02 18:33 ` [PATCH v3 09/12] KVM: x86: hyper-v: Deactivate APICv only when AutoEOI feature is in use Maxim Levitsky
2021-08-03 8:47 ` Paolo Bonzini
2021-08-03 9:01 ` Paolo Bonzini
2021-08-03 9:11 ` Paolo Bonzini
2021-08-02 18:33 ` [PATCH v3 10/12] KVM: SVM: remove svm_toggle_avic_for_irq_window Maxim Levitsky
2021-08-03 9:11 ` Paolo Bonzini
2021-08-02 18:33 ` [PATCH v3 11/12] KVM: SVM: call avic_vcpu_load/avic_vcpu_put when enabling/disabling AVIC Maxim Levitsky
2021-08-03 9:00 ` Paolo Bonzini [this message]
2021-08-02 18:33 ` [PATCH v3 12/12] KVM: SVM: AVIC: drop unsupported AVIC base relocation code Maxim Levitsky
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=5a3b940b-7290-ca37-b3a4-bf01b7c4a6bb@redhat.com \
--to=pbonzini@redhat.com \
--cc=bp@alien8.de \
--cc=hpa@zytor.com \
--cc=jmattson@google.com \
--cc=joro@8bytes.org \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=mlevitsk@redhat.com \
--cc=seanjc@google.com \
--cc=suravee.suthikulpanit@amd.com \
--cc=tglx@linutronix.de \
--cc=vkuznets@redhat.com \
--cc=wanpengli@tencent.com \
--cc=x86@kernel.org \
/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).