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In-Reply-To: <81112cec-72fa-dd8c-21c8-b24f51021f43@de.ibm.com>
From:   Wanpeng Li <kernellwp@gmail.com>
Date:   Tue, 13 Apr 2021 15:38:40 +0800
Message-ID: <CANRm+CwNxcKPKdV4Bxr-5sWJtg_SKZEN5atGJKRyLcVnWVSKSg@mail.gmail.com>
Subject: Re: [PATCH v2 1/3] context_tracking: Split guest_enter/exit_irqoff
To:     Christian Borntraeger <borntraeger@de.ibm.com>
Cc:     LKML <linux-kernel@vger.kernel.org>, kvm <kvm@vger.kernel.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Sean Christopherson <seanjc@google.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Michael Tokarev <mjt@tls.msk.ru>
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On Tue, 13 Apr 2021 at 15:35, Christian Borntraeger
<borntraeger@de.ibm.com> wrote:
>
>
>
> On 13.04.21 09:16, Wanpeng Li wrote:
> [...]
>
> > @@ -145,6 +155,13 @@ static __always_inline void guest_exit_irqoff(void)
> >   }
> >
> >   #else
> > +static __always_inline void context_guest_enter_irqoff(void)
> > +{
> > +     instrumentation_begin();
> > +     rcu_virt_note_context_switch(smp_processor_id());
> > +     instrumentation_end();
> > +}
> > +
> >   static __always_inline void guest_enter_irqoff(void)
> >   {
> >       /*
> > @@ -155,10 +172,13 @@ static __always_inline void guest_enter_irqoff(void)
> >       instrumentation_begin();
> >       vtime_account_kernel(current);
> >       current->flags |= PF_VCPU;
> > -     rcu_virt_note_context_switch(smp_processor_id());
> >       instrumentation_end();
> > +
> > +     context_guest_enter_irqoff();
>
> So we now do instrumentation_begin 2 times?

Similar to context_guest_enter_irqoff() ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN.

    Wanpeng