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;
Subject: Re: [PATCH] crypto: x86/crc32c-intel - Don't match some Zhaoxin CPUs
To:     Herbert Xu <herbert@gondor.apana.org.au>
CC:     <davem@davemloft.net>, <tglx@linutronix.de>, <mingo@redhat.com>,
        <bp@alien8.de>, <x86@kernel.org>, <hpa@zytor.com>,
        <linux-crypto@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <TimGuo-oc@zhaoxin.com>, <CooperYan@zhaoxin.com>,
        <QiyuanWang@zhaoxin.com>, <HerryYang@zhaoxin.com>,
        <CobeChen@zhaoxin.com>, <SilviaZhao@zhaoxin.com>
References: <1608028091-29439-1-git-send-email-TonyWWang-oc@zhaoxin.com>
 <20210102211200.GA1750@gondor.apana.org.au>
From:   Tony W Wang-oc <TonyWWang-oc@zhaoxin.com>
Message-ID: <464482ed-bce6-7e55-bd34-b3be736a6e8b@zhaoxin.com>
Date:   Thu, 7 Jan 2021 14:27:00 +0800
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101
 Thunderbird/60.8.0
MIME-Version: 1.0
In-Reply-To: <20210102211200.GA1750@gondor.apana.org.au>
Content-Type: text/plain; charset="utf-8"
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 03/01/2021 05:12, Herbert Xu wrote:
> On Tue, Dec 15, 2020 at 06:28:11PM +0800, Tony W Wang-oc wrote:
>> The driver crc32c-intel match CPUs supporting X86_FEATURE_XMM4_2.
>> On platforms with Zhaoxin CPUs supporting this X86 feature, when
>> crc32c-intel and crc32c-generic are both registered, system will
>> use crc32c-intel because its .cra_priority is greater than
>> crc32c-generic.
>>
>> When doing lmbench3 Create and Delete file test on partitions with
>> ext4 enabling metadata checksum, found using crc32c-generic driver
>> could get about 20% performance gain than using the driver crc32c-intel
>> on some Zhaoxin CPUs.
>>
>> This case expect to use crc32c-generic driver for these Zhaoxin CPUs
>> to get performance gain, so remove these Zhaoxin CPUs support from
>> crc32c-intel.
>>
>> Signed-off-by: Tony W Wang-oc <TonyWWang-oc@zhaoxin.com>
>> ---
>>  arch/x86/crypto/crc32c-intel_glue.c | 21 +++++++++++++++++++--
>>  1 file changed, 19 insertions(+), 2 deletions(-)
> 
> This does not seem to address the latest comment from hpa.
> 

Yes, please ignore this patch. Have send new patch set per Hpa's suggestion.

Sincerely
Tonyw

> Thanks,
>