From: "Jason A. Donenfeld" <Jason@zx2c4.com>
Subject: Re: [PATCH] poly1305: generic C can be faster on chips with slow
 unaligned access
Date: Wed, 2 Nov 2016 23:00:00 +0100
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Cc: "David S. Miller" <davem@davemloft.net>,
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        Martin Willi <martin@strongswan.org>
To: Herbert Xu <herbert@gondor.apana.org.au>
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On Wed, Nov 2, 2016 at 10:26 PM, Herbert Xu <herbert@gondor.apana.org.au> wrote:
> What I'm interested in is whether the new code is sufficiently
> close in performance to the old code, particularonly on x86.
>
> I'd much rather only have a single set of code for all architectures.
> After all, this is meant to be a generic implementation.

Just tested. I get a 6% slowdown on my Skylake. No good. I think it's
probably best to have the two paths in there, and not reduce it to
one.