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Subject: Re: [PATCH] Performance Improvement in CRC16 Calculations.
From:   Joe Perches <joe@perches.com>
To:     dgilbert@interlog.com, Nicolas Pitre <nicolas.pitre@linaro.org>
Cc:     Jeff Lien <jeff.lien@wdc.com>, linux-kernel@vger.kernel.org,
        linux-crypto@vger.kernel.org, linux-block@vger.kernel.org,
        linux-scsi@vger.kernel.org, herbert@gondor.apana.org.au,
        tim.c.chen@linux.intel.com, martin.petersen@oracle.com,
        david.darrington@wdc.com, jeff.furlong@wdc.com
Date:   Sat, 11 Aug 2018 08:06:10 -0700
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On Sat, 2018-08-11 at 02:04 -0700, Joe Perches wrote:
> On Fri, 2018-08-10 at 22:39 -0400, Douglas Gilbert wrote:
> > but below is a copy and paste of a table 27 from draft SBC-4
> > revision 15 in chapter 4.22.4.4 on page 87.
> 
> The posted code returns the proper crc for each
> CONFIG_CRYPTO_CRCT10DIF_TABLE_SIZE value from
> 1 to 5 for these arrays.

Jeff, could you please test the suggested patch
with your comparison framework again with each
CONFIG_CRYPTO_CRCT10DIF_TABLE_SIZE from 1 to 5?

I get on a very limited test framework here:
(runtime average of 10 runs)

1: 4.32
2: 1.86
3: 1.31
4: 1.05
5: 0.99