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From:   Shunsuke Mie <mie@igel.co.jp>
Date:   Tue, 27 Dec 2022 16:13:49 +0900
Message-ID: <CANXvt5pXkS=TTOU0+Lkx6CjcV7xvDHRS6FbFikJ4Ww8832sg8g@mail.gmail.com>
Subject: Re: [RFC PATCH 2/9] vringh: remove vringh_iov and unite to vringh_kiov
To:     "Michael S. Tsirkin" <mst@redhat.com>
Cc:     Jason Wang <jasowang@redhat.com>,
        Rusty Russell <rusty@rustcorp.com.au>, kvm@vger.kernel.org,
        virtualization@lists.linux-foundation.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
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2022=E5=B9=B412=E6=9C=8827=E6=97=A5(=E7=81=AB) 16:05 Michael S. Tsirkin <ms=
t@redhat.com>:
>
> On Tue, Dec 27, 2022 at 02:04:03PM +0800, Jason Wang wrote:
> > On Tue, Dec 27, 2022 at 10:25 AM Shunsuke Mie <mie@igel.co.jp> wrote:
> > >
> > > struct vringh_iov is defined to hold userland addresses. However, to =
use
> > > common function, __vring_iov, finally the vringh_iov converts to the
> > > vringh_kiov with simple cast. It includes compile time check code to =
make
> > > sure it can be cast correctly.
> > >
> > > To simplify the code, this patch removes the struct vringh_iov and un=
ifies
> > > APIs to struct vringh_kiov.
> > >
> > > Signed-off-by: Shunsuke Mie <mie@igel.co.jp>
> >
> > While at this, I wonder if we need to go further, that is, switch to
> > using an iov iterator instead of a vringh customized one.
> >
> > Thanks
>
> Possibly, but when doing changes like this one needs to be careful
> to avoid breaking all the inlining tricks vringh relies on for
> performance.
Definitely, I'm evaluating the performance using vringh_test. I'll add a
result of the evaluation. But, If there are other evaluation methods, could=
 you
please tell me?
> --
> MST
>

Best,
Shunsuke