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Date:   Thu, 20 Aug 2020 17:06:45 +1000
From:   Herbert Xu <herbert@gondor.apana.org.au>
To:     Ard Biesheuvel <ardb@kernel.org>
Cc:     Ben Greear <greearb@candelatech.com>,
        Linux Crypto Mailing List <linux-crypto@vger.kernel.org>,
        Eric Biggers <ebiggers@kernel.org>
Subject: Re: [PATCH 0/5] crypto: Implement cmac based on cbc skcipher
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On Thu, Aug 20, 2020 at 09:04:26AM +0200, Ard Biesheuvel wrote:
>
> I don't disagree with that, especially given all the effort that went
> into optimizing FPU preserve/restore on both arm64 and x86. But the
> bottom line is that this is what is causing the degradation in Ben's
> case, so we cannot disregard it.

If he's having problems with the performance when SIMD is in use
due to preserve/restore, I'd hate to see his numbers when SIMD is
not available.

IOW if this really matters to him, then wireless code needs to switch
over to ahash.

Solving half of the problem simply makes no 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