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From:   Ben Gardon <bgardon@google.com>
Date:   Mon, 10 May 2021 09:37:51 -0700
Message-ID: <CANgfPd_uM+jXD=2m-EK-Vsz4UtB0hd-EFAA-m-y74fZf18rOpQ@mail.gmail.com>
Subject: Re: [PATCH v3 5/8] KVM: x86/mmu: Add a field to control memslot rmap allocation
To:     Paolo Bonzini <pbonzini@redhat.com>
Cc:     LKML <linux-kernel@vger.kernel.org>, kvm <kvm@vger.kernel.org>,
        Peter Xu <peterx@redhat.com>,
        Sean Christopherson <seanjc@google.com>,
        Peter Shier <pshier@google.com>,
        Yulei Zhang <yulei.kernel@gmail.com>,
        Wanpeng Li <kernellwp@gmail.com>,
        Xiao Guangrong <xiaoguangrong.eric@gmail.com>,
        Kai Huang <kai.huang@intel.com>,
        Keqian Zhu <zhukeqian1@huawei.com>
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On Mon, May 10, 2021 at 9:33 AM Paolo Bonzini <pbonzini@redhat.com> wrote:
>
> On 10/05/21 18:14, Ben Gardon wrote:
> >> Possibly stupid (or at least lazy) question: why can't it be a "normal"
> >> static inline function?
> > That was my initial approach (hence the leftover inline) but I got
> > some warnings about a forward declaration of struct kvm because
> > arch/x86/include/asm/kvm_host.h doesn't include virt/kvm/kvm_host.h.
> > Maybe there's a way to fix that, but I didn't want to mess with it.
> >
>
> Let's just use the field directly.

That works for me too. I moved to the wrapper because adding the
smp_load_acquire and a comment explaining why we were doing that
looked bloated and I thought it would be easier to document in one
place, but it's not that much bloat, and having the subtleties
documented directly in the function is probably clearer for readers
anyway.

>
> Paolo
>