Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
References: <1601027469-221812-1-git-send-email-john.garry@huawei.com>
In-Reply-To: <1601027469-221812-1-git-send-email-john.garry@huawei.com>
From:   Cong Wang <xiyou.wangcong@gmail.com>
Date:   Fri, 25 Sep 2020 12:26:28 -0700
Message-ID: <CAM_iQpUowPbuqx7-LsZTZ71KxTPpXAUqYU5+aWPy+qv0U2BqTg@mail.gmail.com>
Subject: Re: [PATCH 0/2] iommu/iova: Solve longterm IOVA issue
To:     John Garry <john.garry@huawei.com>
Cc:     Joerg Roedel <joro@8bytes.org>,
        Robin Murphy <robin.murphy@arm.com>,
        iommu@lists.linux-foundation.org,
        LKML <linux-kernel@vger.kernel.org>,
        chenxiang <chenxiang66@hisilicon.com>, linuxarm@huawei.com,
        thunder.leizhen@huawei.com
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Fri, Sep 25, 2020 at 2:56 AM John Garry <john.garry@huawei.com> wrote:
>
> This series contains a patch to solve the longterm IOVA issue which
> leizhen originally tried to address at [0].
>
> I also included the small optimisation from Cong Wang, which never seems
> to be have been accepted [1]. There was some debate of the other patches
> in that series, but this one is quite straightforward.
>
> @Cong Wang, Please resend your series if prefer I didn't upstream your
> patch.

Thanks for letting me know. But I still don't think it is worth any effort,
given it is hard to work with Robin. Users who care about latency here
should just disable IOMMU, it is really hard to optimize IOVA cache
performance to catch up with !IOMMU case.

So, please feel free to carry it on your own, I have no problem with it.

Thanks.