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Date:   Tue, 27 Dec 2022 02:05:42 -0500
From:   "Michael S. Tsirkin" <mst@redhat.com>
To:     Jason Wang <jasowang@redhat.com>
Cc:     Shunsuke Mie <mie@igel.co.jp>,
        Rusty Russell <rusty@rustcorp.com.au>, kvm@vger.kernel.org,
        virtualization@lists.linux-foundation.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [RFC PATCH 2/9] vringh: remove vringh_iov and unite to
 vringh_kiov
Message-ID: <20221227020425-mutt-send-email-mst@kernel.org>
References: <20221227022528.609839-1-mie@igel.co.jp>
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 <CACGkMEtAaYpuZtS0gx_m931nFzcvqSNK9BhvUZH_tZXTzjgQCg@mail.gmail.com>
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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 unifies
> > 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.

-- 
MST