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Subject: Re: [PATCH 4/4] crypto: hisilicon/sec2 - Add pbuffer mode for SEC
 driver
To:     John Garry <john.garry@huawei.com>, <herbert@gondor.apana.org.au>,
        <davem@davemloft.net>
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        <zhangwei375@huawei.com>, <shenyang39@huawei.com>,
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From:   Xu Zaibo <xuzaibo@huawei.com>
Message-ID: <bac7ec3e-43e6-9061-fbbe-03f4404f1c50@huawei.com>
Date:   Thu, 20 Feb 2020 20:16:01 +0800
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On 2020/2/20 19:07, John Garry wrote:
> On 20/02/2020 10:10, Xu Zaibo wrote:
>> Hi,
>>
>>
>> On 2020/2/20 17:50, John Garry wrote:
>>> On 20/02/2020 09:04, Zaibo Xu wrote:
>>>> From: liulongfang <liulongfang@huawei.com>
>>>>
>>>> In the scenario of SMMU translation, the SEC performance of short 
>>>> messages
>>>> (<512Bytes) cannot meet our expectations. To avoid this, we reserve 
>>>> the
>>>> plat buffer (PBUF) memory for small packets when creating TFM.
>>>>
>>>
>>> I haven't gone through the code here, but why not use this method 
>>> also for non-translated? What are the pros and cons?
>> Because non-translated has no performance or throughput problems.
>>
>
> OK, so no problem, but I was asking could it be improved, and, if so, 
> what would be the drawbacks?
>
> As for the change to check if the IOMMU is translating, it seems exact 
> same as that for the hi1616 driver...
>
Currently, I find the only drawback is needing more memory :), what's 
your idea?
Yes, the same as SEC V1.

Cheers,
Zaibo

.
>>
>> .
>>>
>>> The commit message is very light on details.
>>>
>>> Thanks
>>> john
>>>
>>> .
>>>
>>
>>
>> .
>
> .
>