Re: [PATCH 0/5] crypto: Implement cmac based on cbc skcipher

[Herbert Xu <herbert@gondor.apana.org.au>]

On Thu, Aug 20, 2020 at 06:54:58AM -0700, Ben Greear wrote:
>
> Here's a run on an:  Intel(R) Core(TM) i7-7700T CPU @ 2.90GHz
> 
>                testing speed of async cmac(aes-aesni) (cmac(aes-aesni))
>
> [  259.397910] tcrypt: test  8 ( 1024 byte blocks, 1024 bytes per update,   1 updates):   8442 cycles/operation,    8 cycles/byte
>
>                testing speed of async cmac(aes-generic) (cmac(aes-generic))
>
> [  294.171530] tcrypt: test  8 ( 1024 byte blocks, 1024 bytes per update,   1 updates):   9022 cycles/operation,    8 cycles/byte
> 
> On my slow apu2 board with processor: AMD GX-412TC SOC
> 
>               testing speed of async cmac(aes-aesni) (cmac(aes-aesni))
>
> [   51.751810] tcrypt: test  8 ( 1024 byte blocks, 1024 bytes per update,   1 updates):  18759 cycles/operation,   18 cycle
>
>               testing speed of async cmac(aes-generic) (cmac(aes-generic))
>
> [   97.837497] tcrypt: test  8 ( 1024 byte blocks, 1024 bytes per update,   1 updates):  31365 cycles/operation,   30 cycle

So clearly aes-generic is slower than aes-aesni even with saving and
restoring for each block.  Therefore improving the performance of
the latter per se does not make sense.

Cheers,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt