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From:   Ben Gardon <bgardon@google.com>
Date:   Wed, 30 Sep 2020 15:23:38 -0700
Message-ID: <CANgfPd89WzcDV+DTxvkqfobCdCXHwtkFwpy90H4oNRftDOVrnA@mail.gmail.com>
Subject: Re: [PATCH 20/22] kvm: mmu: NX largepage recovery for TDP MMU
To:     Paolo Bonzini <pbonzini@redhat.com>
Cc:     LKML <linux-kernel@vger.kernel.org>, kvm <kvm@vger.kernel.org>,
        Cannon Matthews <cannonmatthews@google.com>,
        Peter Xu <peterx@redhat.com>,
        Sean Christopherson <sean.j.christopherson@intel.com>,
        Peter Shier <pshier@google.com>,
        Peter Feiner <pfeiner@google.com>,
        Junaid Shahid <junaids@google.com>,
        Jim Mattson <jmattson@google.com>,
        Yulei Zhang <yulei.kernel@gmail.com>,
        Wanpeng Li <kernellwp@gmail.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Xiao Guangrong <xiaoguangrong.eric@gmail.com>
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On Fri, Sep 25, 2020 at 6:15 PM Paolo Bonzini <pbonzini@redhat.com> wrote:
>
> On 25/09/20 23:23, Ben Gardon wrote:
> > +
> > +     if (!kvm->arch.tdp_mmu_enabled)
> > +             return err;
> > +
> > +     err = kvm_vm_create_worker_thread(kvm, kvm_nx_lpage_recovery_worker, 1,
> > +                     "kvm-nx-lpage-tdp-mmu-recovery",
> > +                     &kvm->arch.nx_lpage_tdp_mmu_recovery_thread);
>
> Any reason to have two threads?
>
> Paolo

At some point it felt cleaner. In this patch set NX reclaim is pretty
similar between the "shadow MMU" and TDP MMU so they don't really need
to be separate threads.

>